1# 2# (C) Copyright 2000 - 2013 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# SPDX-License-Identifier: GPL-2.0+ 6# 7 8Summary: 9======== 10 11This directory contains the source code for U-Boot, a boot loader for 12Embedded boards based on PowerPC, ARM, MIPS and several other 13processors, which can be installed in a boot ROM and used to 14initialize and test the hardware or to download and run application 15code. 16 17The development of U-Boot is closely related to Linux: some parts of 18the source code originate in the Linux source tree, we have some 19header files in common, and special provision has been made to 20support booting of Linux images. 21 22Some attention has been paid to make this software easily 23configurable and extendable. For instance, all monitor commands are 24implemented with the same call interface, so that it's very easy to 25add new commands. Also, instead of permanently adding rarely used 26code (for instance hardware test utilities) to the monitor, you can 27load and run it dynamically. 28 29 30Status: 31======= 32 33In general, all boards for which a configuration option exists in the 34Makefile have been tested to some extent and can be considered 35"working". In fact, many of them are used in production systems. 36 37In case of problems see the CHANGELOG and CREDITS files to find out 38who contributed the specific port. The boards.cfg file lists board 39maintainers. 40 41Note: There is no CHANGELOG file in the actual U-Boot source tree; 42it can be created dynamically from the Git log using: 43 44 make CHANGELOG 45 46 47Where to get help: 48================== 49 50In case you have questions about, problems with or contributions for 51U-Boot you should send a message to the U-Boot mailing list at 52<u-boot@lists.denx.de>. There is also an archive of previous traffic 53on the mailing list - please search the archive before asking FAQ's. 54Please see http://lists.denx.de/pipermail/u-boot and 55http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 56 57 58Where to get source code: 59========================= 60 61The U-Boot source code is maintained in the git repository at 62git://www.denx.de/git/u-boot.git ; you can browse it online at 63http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 64 65The "snapshot" links on this page allow you to download tarballs of 66any version you might be interested in. Official releases are also 67available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 68directory. 69 70Pre-built (and tested) images are available from 71ftp://ftp.denx.de/pub/u-boot/images/ 72 73 74Where we come from: 75=================== 76 77- start from 8xxrom sources 78- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 79- clean up code 80- make it easier to add custom boards 81- make it possible to add other [PowerPC] CPUs 82- extend functions, especially: 83 * Provide extended interface to Linux boot loader 84 * S-Record download 85 * network boot 86 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 87- create ARMBoot project (http://sourceforge.net/projects/armboot) 88- add other CPU families (starting with ARM) 89- create U-Boot project (http://sourceforge.net/projects/u-boot) 90- current project page: see http://www.denx.de/wiki/U-Boot 91 92 93Names and Spelling: 94=================== 95 96The "official" name of this project is "Das U-Boot". The spelling 97"U-Boot" shall be used in all written text (documentation, comments 98in source files etc.). Example: 99 100 This is the README file for the U-Boot project. 101 102File names etc. shall be based on the string "u-boot". Examples: 103 104 include/asm-ppc/u-boot.h 105 106 #include <asm/u-boot.h> 107 108Variable names, preprocessor constants etc. shall be either based on 109the string "u_boot" or on "U_BOOT". Example: 110 111 U_BOOT_VERSION u_boot_logo 112 IH_OS_U_BOOT u_boot_hush_start 113 114 115Versioning: 116=========== 117 118Starting with the release in October 2008, the names of the releases 119were changed from numerical release numbers without deeper meaning 120into a time stamp based numbering. Regular releases are identified by 121names consisting of the calendar year and month of the release date. 122Additional fields (if present) indicate release candidates or bug fix 123releases in "stable" maintenance trees. 124 125Examples: 126 U-Boot v2009.11 - Release November 2009 127 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 128 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 129 130 131Directory Hierarchy: 132==================== 133 134/arch Architecture specific files 135 /arc Files generic to ARC architecture 136 /cpu CPU specific files 137 /arc700 Files specific to ARC 700 CPUs 138 /lib Architecture specific library files 139 /arm Files generic to ARM architecture 140 /cpu CPU specific files 141 /arm720t Files specific to ARM 720 CPUs 142 /arm920t Files specific to ARM 920 CPUs 143 /at91 Files specific to Atmel AT91RM9200 CPU 144 /imx Files specific to Freescale MC9328 i.MX CPUs 145 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 146 /arm926ejs Files specific to ARM 926 CPUs 147 /arm1136 Files specific to ARM 1136 CPUs 148 /pxa Files specific to Intel XScale PXA CPUs 149 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 150 /lib Architecture specific library files 151 /avr32 Files generic to AVR32 architecture 152 /cpu CPU specific files 153 /lib Architecture specific library files 154 /blackfin Files generic to Analog Devices Blackfin architecture 155 /cpu CPU specific files 156 /lib Architecture specific library files 157 /m68k Files generic to m68k architecture 158 /cpu CPU specific files 159 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 160 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 161 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 162 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 163 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 164 /lib Architecture specific library files 165 /microblaze Files generic to microblaze architecture 166 /cpu CPU specific files 167 /lib Architecture specific library files 168 /mips Files generic to MIPS architecture 169 /cpu CPU specific files 170 /mips32 Files specific to MIPS32 CPUs 171 /mips64 Files specific to MIPS64 CPUs 172 /lib Architecture specific library files 173 /nds32 Files generic to NDS32 architecture 174 /cpu CPU specific files 175 /n1213 Files specific to Andes Technology N1213 CPUs 176 /lib Architecture specific library files 177 /nios2 Files generic to Altera NIOS2 architecture 178 /cpu CPU specific files 179 /lib Architecture specific library files 180 /openrisc Files generic to OpenRISC architecture 181 /cpu CPU specific files 182 /lib Architecture specific library files 183 /powerpc Files generic to PowerPC architecture 184 /cpu CPU specific files 185 /mpc5xx Files specific to Freescale MPC5xx CPUs 186 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 187 /mpc8xx Files specific to Freescale MPC8xx CPUs 188 /mpc8260 Files specific to Freescale MPC8260 CPUs 189 /mpc85xx Files specific to Freescale MPC85xx CPUs 190 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 191 /lib Architecture specific library files 192 /sh Files generic to SH architecture 193 /cpu CPU specific files 194 /sh2 Files specific to sh2 CPUs 195 /sh3 Files specific to sh3 CPUs 196 /sh4 Files specific to sh4 CPUs 197 /lib Architecture specific library files 198 /sparc Files generic to SPARC architecture 199 /cpu CPU specific files 200 /leon2 Files specific to Gaisler LEON2 SPARC CPU 201 /leon3 Files specific to Gaisler LEON3 SPARC CPU 202 /lib Architecture specific library files 203 /x86 Files generic to x86 architecture 204 /cpu CPU specific files 205 /lib Architecture specific library files 206/api Machine/arch independent API for external apps 207/board Board dependent files 208/common Misc architecture independent functions 209/disk Code for disk drive partition handling 210/doc Documentation (don't expect too much) 211/drivers Commonly used device drivers 212/dts Contains Makefile for building internal U-Boot fdt. 213/examples Example code for standalone applications, etc. 214/fs Filesystem code (cramfs, ext2, jffs2, etc.) 215/include Header Files 216/lib Files generic to all architectures 217 /libfdt Library files to support flattened device trees 218 /lzma Library files to support LZMA decompression 219 /lzo Library files to support LZO decompression 220/net Networking code 221/post Power On Self Test 222/spl Secondary Program Loader framework 223/tools Tools to build S-Record or U-Boot images, etc. 224 225Software Configuration: 226======================= 227 228Configuration is usually done using C preprocessor defines; the 229rationale behind that is to avoid dead code whenever possible. 230 231There are two classes of configuration variables: 232 233* Configuration _OPTIONS_: 234 These are selectable by the user and have names beginning with 235 "CONFIG_". 236 237* Configuration _SETTINGS_: 238 These depend on the hardware etc. and should not be meddled with if 239 you don't know what you're doing; they have names beginning with 240 "CONFIG_SYS_". 241 242Later we will add a configuration tool - probably similar to or even 243identical to what's used for the Linux kernel. Right now, we have to 244do the configuration by hand, which means creating some symbolic 245links and editing some configuration files. We use the TQM8xxL boards 246as an example here. 247 248 249Selection of Processor Architecture and Board Type: 250--------------------------------------------------- 251 252For all supported boards there are ready-to-use default 253configurations available; just type "make <board_name>_defconfig". 254 255Example: For a TQM823L module type: 256 257 cd u-boot 258 make TQM823L_defconfig 259 260For the Cogent platform, you need to specify the CPU type as well; 261e.g. "make cogent_mpc8xx_defconfig". And also configure the cogent 262directory according to the instructions in cogent/README. 263 264 265Sandbox Environment: 266-------------------- 267 268U-Boot can be built natively to run on a Linux host using the 'sandbox' 269board. This allows feature development which is not board- or architecture- 270specific to be undertaken on a native platform. The sandbox is also used to 271run some of U-Boot's tests. 272 273See board/sandbox/README.sandbox for more details. 274 275 276Board Initialisation Flow: 277-------------------------- 278 279This is the intended start-up flow for boards. This should apply for both 280SPL and U-Boot proper (i.e. they both follow the same rules). At present SPL 281mostly uses a separate code path, but the funtion names and roles of each 282function are the same. Some boards or architectures may not conform to this. 283At least most ARM boards which use CONFIG_SPL_FRAMEWORK conform to this. 284 285Execution starts with start.S with three functions called during init after 286that. The purpose and limitations of each is described below. 287 288lowlevel_init(): 289 - purpose: essential init to permit execution to reach board_init_f() 290 - no global_data or BSS 291 - there is no stack (ARMv7 may have one but it will soon be removed) 292 - must not set up SDRAM or use console 293 - must only do the bare minimum to allow execution to continue to 294 board_init_f() 295 - this is almost never needed 296 - return normally from this function 297 298board_init_f(): 299 - purpose: set up the machine ready for running board_init_r(): 300 i.e. SDRAM and serial UART 301 - global_data is available 302 - stack is in SRAM 303 - BSS is not available, so you cannot use global/static variables, 304 only stack variables and global_data 305 306 Non-SPL-specific notes: 307 - dram_init() is called to set up DRAM. If already done in SPL this 308 can do nothing 309 310 SPL-specific notes: 311 - you can override the entire board_init_f() function with your own 312 version as needed. 313 - preloader_console_init() can be called here in extremis 314 - should set up SDRAM, and anything needed to make the UART work 315 - these is no need to clear BSS, it will be done by crt0.S 316 - must return normally from this function (don't call board_init_r() 317 directly) 318 319Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 320this point the stack and global_data are relocated to below 321CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 322memory. 323 324board_init_r(): 325 - purpose: main execution, common code 326 - global_data is available 327 - SDRAM is available 328 - BSS is available, all static/global variables can be used 329 - execution eventually continues to main_loop() 330 331 Non-SPL-specific notes: 332 - U-Boot is relocated to the top of memory and is now running from 333 there. 334 335 SPL-specific notes: 336 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 337 CONFIG_SPL_STACK_R_ADDR points into SDRAM 338 - preloader_console_init() can be called here - typically this is 339 done by defining CONFIG_SPL_BOARD_INIT and then supplying a 340 spl_board_init() function containing this call 341 - loads U-Boot or (in falcon mode) Linux 342 343 344 345Configuration Options: 346---------------------- 347 348Configuration depends on the combination of board and CPU type; all 349such information is kept in a configuration file 350"include/configs/<board_name>.h". 351 352Example: For a TQM823L module, all configuration settings are in 353"include/configs/TQM823L.h". 354 355 356Many of the options are named exactly as the corresponding Linux 357kernel configuration options. The intention is to make it easier to 358build a config tool - later. 359 360 361The following options need to be configured: 362 363- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 364 365- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 366 367- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 368 Define exactly one, e.g. CONFIG_ATSTK1002 369 370- CPU Module Type: (if CONFIG_COGENT is defined) 371 Define exactly one of 372 CONFIG_CMA286_60_OLD 373--- FIXME --- not tested yet: 374 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 375 CONFIG_CMA287_23, CONFIG_CMA287_50 376 377- Motherboard Type: (if CONFIG_COGENT is defined) 378 Define exactly one of 379 CONFIG_CMA101, CONFIG_CMA102 380 381- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 382 Define one or more of 383 CONFIG_CMA302 384 385- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 386 Define one or more of 387 CONFIG_LCD_HEARTBEAT - update a character position on 388 the LCD display every second with 389 a "rotator" |\-/|\-/ 390 391- Marvell Family Member 392 CONFIG_SYS_MVFS - define it if you want to enable 393 multiple fs option at one time 394 for marvell soc family 395 396- 8xx CPU Options: (if using an MPC8xx CPU) 397 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 398 get_gclk_freq() cannot work 399 e.g. if there is no 32KHz 400 reference PIT/RTC clock 401 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 402 or XTAL/EXTAL) 403 404- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 405 CONFIG_SYS_8xx_CPUCLK_MIN 406 CONFIG_SYS_8xx_CPUCLK_MAX 407 CONFIG_8xx_CPUCLK_DEFAULT 408 See doc/README.MPC866 409 410 CONFIG_SYS_MEASURE_CPUCLK 411 412 Define this to measure the actual CPU clock instead 413 of relying on the correctness of the configured 414 values. Mostly useful for board bringup to make sure 415 the PLL is locked at the intended frequency. Note 416 that this requires a (stable) reference clock (32 kHz 417 RTC clock or CONFIG_SYS_8XX_XIN) 418 419 CONFIG_SYS_DELAYED_ICACHE 420 421 Define this option if you want to enable the 422 ICache only when Code runs from RAM. 423 424- 85xx CPU Options: 425 CONFIG_SYS_PPC64 426 427 Specifies that the core is a 64-bit PowerPC implementation (implements 428 the "64" category of the Power ISA). This is necessary for ePAPR 429 compliance, among other possible reasons. 430 431 CONFIG_SYS_FSL_TBCLK_DIV 432 433 Defines the core time base clock divider ratio compared to the 434 system clock. On most PQ3 devices this is 8, on newer QorIQ 435 devices it can be 16 or 32. The ratio varies from SoC to Soc. 436 437 CONFIG_SYS_FSL_PCIE_COMPAT 438 439 Defines the string to utilize when trying to match PCIe device 440 tree nodes for the given platform. 441 442 CONFIG_SYS_PPC_E500_DEBUG_TLB 443 444 Enables a temporary TLB entry to be used during boot to work 445 around limitations in e500v1 and e500v2 external debugger 446 support. This reduces the portions of the boot code where 447 breakpoints and single stepping do not work. The value of this 448 symbol should be set to the TLB1 entry to be used for this 449 purpose. 450 451 CONFIG_SYS_FSL_ERRATUM_A004510 452 453 Enables a workaround for erratum A004510. If set, 454 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 455 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 456 457 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 458 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 459 460 Defines one or two SoC revisions (low 8 bits of SVR) 461 for which the A004510 workaround should be applied. 462 463 The rest of SVR is either not relevant to the decision 464 of whether the erratum is present (e.g. p2040 versus 465 p2041) or is implied by the build target, which controls 466 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 467 468 See Freescale App Note 4493 for more information about 469 this erratum. 470 471 CONFIG_A003399_NOR_WORKAROUND 472 Enables a workaround for IFC erratum A003399. It is only 473 required during NOR boot. 474 475 CONFIG_A008044_WORKAROUND 476 Enables a workaround for T1040/T1042 erratum A008044. It is only 477 required during NAND boot and valid for Rev 1.0 SoC revision 478 479 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 480 481 This is the value to write into CCSR offset 0x18600 482 according to the A004510 workaround. 483 484 CONFIG_SYS_FSL_DSP_DDR_ADDR 485 This value denotes start offset of DDR memory which is 486 connected exclusively to the DSP cores. 487 488 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 489 This value denotes start offset of M2 memory 490 which is directly connected to the DSP core. 491 492 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 493 This value denotes start offset of M3 memory which is directly 494 connected to the DSP core. 495 496 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 497 This value denotes start offset of DSP CCSR space. 498 499 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 500 Single Source Clock is clocking mode present in some of FSL SoC's. 501 In this mode, a single differential clock is used to supply 502 clocks to the sysclock, ddrclock and usbclock. 503 504 CONFIG_SYS_CPC_REINIT_F 505 This CONFIG is defined when the CPC is configured as SRAM at the 506 time of U-boot entry and is required to be re-initialized. 507 508 CONFIG_DEEP_SLEEP 509 Indicates this SoC supports deep sleep feature. If deep sleep is 510 supported, core will start to execute uboot when wakes up. 511 512- Generic CPU options: 513 CONFIG_SYS_GENERIC_GLOBAL_DATA 514 Defines global data is initialized in generic board board_init_f(). 515 If this macro is defined, global data is created and cleared in 516 generic board board_init_f(). Without this macro, architecture/board 517 should initialize global data before calling board_init_f(). 518 519 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 520 521 Defines the endianess of the CPU. Implementation of those 522 values is arch specific. 523 524 CONFIG_SYS_FSL_DDR 525 Freescale DDR driver in use. This type of DDR controller is 526 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 527 SoCs. 528 529 CONFIG_SYS_FSL_DDR_ADDR 530 Freescale DDR memory-mapped register base. 531 532 CONFIG_SYS_FSL_DDR_EMU 533 Specify emulator support for DDR. Some DDR features such as 534 deskew training are not available. 535 536 CONFIG_SYS_FSL_DDRC_GEN1 537 Freescale DDR1 controller. 538 539 CONFIG_SYS_FSL_DDRC_GEN2 540 Freescale DDR2 controller. 541 542 CONFIG_SYS_FSL_DDRC_GEN3 543 Freescale DDR3 controller. 544 545 CONFIG_SYS_FSL_DDRC_GEN4 546 Freescale DDR4 controller. 547 548 CONFIG_SYS_FSL_DDRC_ARM_GEN3 549 Freescale DDR3 controller for ARM-based SoCs. 550 551 CONFIG_SYS_FSL_DDR1 552 Board config to use DDR1. It can be enabled for SoCs with 553 Freescale DDR1 or DDR2 controllers, depending on the board 554 implemetation. 555 556 CONFIG_SYS_FSL_DDR2 557 Board config to use DDR2. It can be eanbeld for SoCs with 558 Freescale DDR2 or DDR3 controllers, depending on the board 559 implementation. 560 561 CONFIG_SYS_FSL_DDR3 562 Board config to use DDR3. It can be enabled for SoCs with 563 Freescale DDR3 or DDR3L controllers. 564 565 CONFIG_SYS_FSL_DDR3L 566 Board config to use DDR3L. It can be enabled for SoCs with 567 DDR3L controllers. 568 569 CONFIG_SYS_FSL_DDR4 570 Board config to use DDR4. It can be enabled for SoCs with 571 DDR4 controllers. 572 573 CONFIG_SYS_FSL_IFC_BE 574 Defines the IFC controller register space as Big Endian 575 576 CONFIG_SYS_FSL_IFC_LE 577 Defines the IFC controller register space as Little Endian 578 579 CONFIG_SYS_FSL_PBL_PBI 580 It enables addition of RCW (Power on reset configuration) in built image. 581 Please refer doc/README.pblimage for more details 582 583 CONFIG_SYS_FSL_PBL_RCW 584 It adds PBI(pre-boot instructions) commands in u-boot build image. 585 PBI commands can be used to configure SoC before it starts the execution. 586 Please refer doc/README.pblimage for more details 587 588 CONFIG_SPL_FSL_PBL 589 It adds a target to create boot binary having SPL binary in PBI format 590 concatenated with u-boot binary. 591 592 CONFIG_SYS_FSL_DDR_BE 593 Defines the DDR controller register space as Big Endian 594 595 CONFIG_SYS_FSL_DDR_LE 596 Defines the DDR controller register space as Little Endian 597 598 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 599 Physical address from the view of DDR controllers. It is the 600 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 601 it could be different for ARM SoCs. 602 603 CONFIG_SYS_FSL_DDR_INTLV_256B 604 DDR controller interleaving on 256-byte. This is a special 605 interleaving mode, handled by Dickens for Freescale layerscape 606 SoCs with ARM core. 607 608 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 609 Number of controllers used as main memory. 610 611 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 612 Number of controllers used for other than main memory. 613 614 CONFIG_SYS_FSL_SEC_BE 615 Defines the SEC controller register space as Big Endian 616 617 CONFIG_SYS_FSL_SEC_LE 618 Defines the SEC controller register space as Little Endian 619 620- Intel Monahans options: 621 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 622 623 Defines the Monahans run mode to oscillator 624 ratio. Valid values are 8, 16, 24, 31. The core 625 frequency is this value multiplied by 13 MHz. 626 627 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 628 629 Defines the Monahans turbo mode to oscillator 630 ratio. Valid values are 1 (default if undefined) and 631 2. The core frequency as calculated above is multiplied 632 by this value. 633 634- MIPS CPU options: 635 CONFIG_SYS_INIT_SP_OFFSET 636 637 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 638 pointer. This is needed for the temporary stack before 639 relocation. 640 641 CONFIG_SYS_MIPS_CACHE_MODE 642 643 Cache operation mode for the MIPS CPU. 644 See also arch/mips/include/asm/mipsregs.h. 645 Possible values are: 646 CONF_CM_CACHABLE_NO_WA 647 CONF_CM_CACHABLE_WA 648 CONF_CM_UNCACHED 649 CONF_CM_CACHABLE_NONCOHERENT 650 CONF_CM_CACHABLE_CE 651 CONF_CM_CACHABLE_COW 652 CONF_CM_CACHABLE_CUW 653 CONF_CM_CACHABLE_ACCELERATED 654 655 CONFIG_SYS_XWAY_EBU_BOOTCFG 656 657 Special option for Lantiq XWAY SoCs for booting from NOR flash. 658 See also arch/mips/cpu/mips32/start.S. 659 660 CONFIG_XWAY_SWAP_BYTES 661 662 Enable compilation of tools/xway-swap-bytes needed for Lantiq 663 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 664 be swapped if a flash programmer is used. 665 666- ARM options: 667 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 668 669 Select high exception vectors of the ARM core, e.g., do not 670 clear the V bit of the c1 register of CP15. 671 672 CONFIG_SYS_THUMB_BUILD 673 674 Use this flag to build U-Boot using the Thumb instruction 675 set for ARM architectures. Thumb instruction set provides 676 better code density. For ARM architectures that support 677 Thumb2 this flag will result in Thumb2 code generated by 678 GCC. 679 680 CONFIG_ARM_ERRATA_716044 681 CONFIG_ARM_ERRATA_742230 682 CONFIG_ARM_ERRATA_743622 683 CONFIG_ARM_ERRATA_751472 684 CONFIG_ARM_ERRATA_761320 685 CONFIG_ARM_ERRATA_773022 686 CONFIG_ARM_ERRATA_774769 687 CONFIG_ARM_ERRATA_794072 688 689 If set, the workarounds for these ARM errata are applied early 690 during U-Boot startup. Note that these options force the 691 workarounds to be applied; no CPU-type/version detection 692 exists, unlike the similar options in the Linux kernel. Do not 693 set these options unless they apply! 694 695 COUNTER_FREQUENCY 696 Generic timer clock source frequency. 697 698 COUNTER_FREQUENCY_REAL 699 Generic timer clock source frequency if the real clock is 700 different from COUNTER_FREQUENCY, and can only be determined 701 at run time. 702 703 NOTE: The following can be machine specific errata. These 704 do have ability to provide rudimentary version and machine 705 specific checks, but expect no product checks. 706 CONFIG_ARM_ERRATA_430973 707 CONFIG_ARM_ERRATA_454179 708 CONFIG_ARM_ERRATA_621766 709 CONFIG_ARM_ERRATA_798870 710 CONFIG_ARM_ERRATA_801819 711 712- Tegra SoC options: 713 CONFIG_TEGRA_SUPPORT_NON_SECURE 714 715 Support executing U-Boot in non-secure (NS) mode. Certain 716 impossible actions will be skipped if the CPU is in NS mode, 717 such as ARM architectural timer initialization. 718 719- Linux Kernel Interface: 720 CONFIG_CLOCKS_IN_MHZ 721 722 U-Boot stores all clock information in Hz 723 internally. For binary compatibility with older Linux 724 kernels (which expect the clocks passed in the 725 bd_info data to be in MHz) the environment variable 726 "clocks_in_mhz" can be defined so that U-Boot 727 converts clock data to MHZ before passing it to the 728 Linux kernel. 729 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 730 "clocks_in_mhz=1" is automatically included in the 731 default environment. 732 733 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 734 735 When transferring memsize parameter to Linux, some versions 736 expect it to be in bytes, others in MB. 737 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 738 739 CONFIG_OF_LIBFDT 740 741 New kernel versions are expecting firmware settings to be 742 passed using flattened device trees (based on open firmware 743 concepts). 744 745 CONFIG_OF_LIBFDT 746 * New libfdt-based support 747 * Adds the "fdt" command 748 * The bootm command automatically updates the fdt 749 750 OF_CPU - The proper name of the cpus node (only required for 751 MPC512X and MPC5xxx based boards). 752 OF_SOC - The proper name of the soc node (only required for 753 MPC512X and MPC5xxx based boards). 754 OF_TBCLK - The timebase frequency. 755 OF_STDOUT_PATH - The path to the console device 756 757 boards with QUICC Engines require OF_QE to set UCC MAC 758 addresses 759 760 CONFIG_OF_BOARD_SETUP 761 762 Board code has addition modification that it wants to make 763 to the flat device tree before handing it off to the kernel 764 765 CONFIG_OF_SYSTEM_SETUP 766 767 Other code has addition modification that it wants to make 768 to the flat device tree before handing it off to the kernel. 769 This causes ft_system_setup() to be called before booting 770 the kernel. 771 772 CONFIG_OF_BOOT_CPU 773 774 This define fills in the correct boot CPU in the boot 775 param header, the default value is zero if undefined. 776 777 CONFIG_OF_IDE_FIXUP 778 779 U-Boot can detect if an IDE device is present or not. 780 If not, and this new config option is activated, U-Boot 781 removes the ATA node from the DTS before booting Linux, 782 so the Linux IDE driver does not probe the device and 783 crash. This is needed for buggy hardware (uc101) where 784 no pull down resistor is connected to the signal IDE5V_DD7. 785 786 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 787 788 This setting is mandatory for all boards that have only one 789 machine type and must be used to specify the machine type 790 number as it appears in the ARM machine registry 791 (see http://www.arm.linux.org.uk/developer/machines/). 792 Only boards that have multiple machine types supported 793 in a single configuration file and the machine type is 794 runtime discoverable, do not have to use this setting. 795 796- vxWorks boot parameters: 797 798 bootvx constructs a valid bootline using the following 799 environments variables: bootfile, ipaddr, serverip, hostname. 800 It loads the vxWorks image pointed bootfile. 801 802 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 803 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 804 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 805 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 806 807 CONFIG_SYS_VXWORKS_ADD_PARAMS 808 809 Add it at the end of the bootline. E.g "u=username pw=secret" 810 811 Note: If a "bootargs" environment is defined, it will overwride 812 the defaults discussed just above. 813 814- Cache Configuration: 815 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 816 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 817 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 818 819- Cache Configuration for ARM: 820 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 821 controller 822 CONFIG_SYS_PL310_BASE - Physical base address of PL310 823 controller register space 824 825- Serial Ports: 826 CONFIG_PL010_SERIAL 827 828 Define this if you want support for Amba PrimeCell PL010 UARTs. 829 830 CONFIG_PL011_SERIAL 831 832 Define this if you want support for Amba PrimeCell PL011 UARTs. 833 834 CONFIG_PL011_CLOCK 835 836 If you have Amba PrimeCell PL011 UARTs, set this variable to 837 the clock speed of the UARTs. 838 839 CONFIG_PL01x_PORTS 840 841 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 842 define this to a list of base addresses for each (supported) 843 port. See e.g. include/configs/versatile.h 844 845 CONFIG_SERIAL_HW_FLOW_CONTROL 846 847 Define this variable to enable hw flow control in serial driver. 848 Current user of this option is drivers/serial/nsl16550.c driver 849 850- Console Interface: 851 Depending on board, define exactly one serial port 852 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 853 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 854 console by defining CONFIG_8xx_CONS_NONE 855 856 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 857 port routines must be defined elsewhere 858 (i.e. serial_init(), serial_getc(), ...) 859 860 CONFIG_CFB_CONSOLE 861 Enables console device for a color framebuffer. Needs following 862 defines (cf. smiLynxEM, i8042) 863 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 864 (default big endian) 865 VIDEO_HW_RECTFILL graphic chip supports 866 rectangle fill 867 (cf. smiLynxEM) 868 VIDEO_HW_BITBLT graphic chip supports 869 bit-blit (cf. smiLynxEM) 870 VIDEO_VISIBLE_COLS visible pixel columns 871 (cols=pitch) 872 VIDEO_VISIBLE_ROWS visible pixel rows 873 VIDEO_PIXEL_SIZE bytes per pixel 874 VIDEO_DATA_FORMAT graphic data format 875 (0-5, cf. cfb_console.c) 876 VIDEO_FB_ADRS framebuffer address 877 VIDEO_KBD_INIT_FCT keyboard int fct 878 (i.e. i8042_kbd_init()) 879 VIDEO_TSTC_FCT test char fct 880 (i.e. i8042_tstc) 881 VIDEO_GETC_FCT get char fct 882 (i.e. i8042_getc) 883 CONFIG_CONSOLE_CURSOR cursor drawing on/off 884 (requires blink timer 885 cf. i8042.c) 886 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 887 CONFIG_CONSOLE_TIME display time/date info in 888 upper right corner 889 (requires CONFIG_CMD_DATE) 890 CONFIG_VIDEO_LOGO display Linux logo in 891 upper left corner 892 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 893 linux_logo.h for logo. 894 Requires CONFIG_VIDEO_LOGO 895 CONFIG_CONSOLE_EXTRA_INFO 896 additional board info beside 897 the logo 898 899 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 900 a limited number of ANSI escape sequences (cursor control, 901 erase functions and limited graphics rendition control). 902 903 When CONFIG_CFB_CONSOLE is defined, video console is 904 default i/o. Serial console can be forced with 905 environment 'console=serial'. 906 907 When CONFIG_SILENT_CONSOLE is defined, all console 908 messages (by U-Boot and Linux!) can be silenced with 909 the "silent" environment variable. See 910 doc/README.silent for more information. 911 912 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 913 is 0x00. 914 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 915 is 0xa0. 916 917- Console Baudrate: 918 CONFIG_BAUDRATE - in bps 919 Select one of the baudrates listed in 920 CONFIG_SYS_BAUDRATE_TABLE, see below. 921 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 922 923- Console Rx buffer length 924 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 925 the maximum receive buffer length for the SMC. 926 This option is actual only for 82xx and 8xx possible. 927 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 928 must be defined, to setup the maximum idle timeout for 929 the SMC. 930 931- Pre-Console Buffer: 932 Prior to the console being initialised (i.e. serial UART 933 initialised etc) all console output is silently discarded. 934 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 935 buffer any console messages prior to the console being 936 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 937 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 938 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 939 bytes are output before the console is initialised, the 940 earlier bytes are discarded. 941 942 Note that when printing the buffer a copy is made on the 943 stack so CONFIG_PRE_CON_BUF_SZ must fit on the stack. 944 945 'Sane' compilers will generate smaller code if 946 CONFIG_PRE_CON_BUF_SZ is a power of 2 947 948- Safe printf() functions 949 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 950 the printf() functions. These are defined in 951 include/vsprintf.h and include snprintf(), vsnprintf() and 952 so on. Code size increase is approximately 300-500 bytes. 953 If this option is not given then these functions will 954 silently discard their buffer size argument - this means 955 you are not getting any overflow checking in this case. 956 957- Boot Delay: CONFIG_BOOTDELAY - in seconds 958 Delay before automatically booting the default image; 959 set to -1 to disable autoboot. 960 set to -2 to autoboot with no delay and not check for abort 961 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 962 963 See doc/README.autoboot for these options that 964 work with CONFIG_BOOTDELAY. None are required. 965 CONFIG_BOOT_RETRY_TIME 966 CONFIG_BOOT_RETRY_MIN 967 CONFIG_AUTOBOOT_KEYED 968 CONFIG_AUTOBOOT_PROMPT 969 CONFIG_AUTOBOOT_DELAY_STR 970 CONFIG_AUTOBOOT_STOP_STR 971 CONFIG_ZERO_BOOTDELAY_CHECK 972 CONFIG_RESET_TO_RETRY 973 974- Autoboot Command: 975 CONFIG_BOOTCOMMAND 976 Only needed when CONFIG_BOOTDELAY is enabled; 977 define a command string that is automatically executed 978 when no character is read on the console interface 979 within "Boot Delay" after reset. 980 981 CONFIG_BOOTARGS 982 This can be used to pass arguments to the bootm 983 command. The value of CONFIG_BOOTARGS goes into the 984 environment value "bootargs". 985 986 CONFIG_RAMBOOT and CONFIG_NFSBOOT 987 The value of these goes into the environment as 988 "ramboot" and "nfsboot" respectively, and can be used 989 as a convenience, when switching between booting from 990 RAM and NFS. 991 992- Bootcount: 993 CONFIG_BOOTCOUNT_LIMIT 994 Implements a mechanism for detecting a repeating reboot 995 cycle, see: 996 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 997 998 CONFIG_BOOTCOUNT_ENV 999 If no softreset save registers are found on the hardware 1000 "bootcount" is stored in the environment. To prevent a 1001 saveenv on all reboots, the environment variable 1002 "upgrade_available" is used. If "upgrade_available" is 1003 0, "bootcount" is always 0, if "upgrade_available" is 1004 1 "bootcount" is incremented in the environment. 1005 So the Userspace Applikation must set the "upgrade_available" 1006 and "bootcount" variable to 0, if a boot was successfully. 1007 1008- Pre-Boot Commands: 1009 CONFIG_PREBOOT 1010 1011 When this option is #defined, the existence of the 1012 environment variable "preboot" will be checked 1013 immediately before starting the CONFIG_BOOTDELAY 1014 countdown and/or running the auto-boot command resp. 1015 entering interactive mode. 1016 1017 This feature is especially useful when "preboot" is 1018 automatically generated or modified. For an example 1019 see the LWMON board specific code: here "preboot" is 1020 modified when the user holds down a certain 1021 combination of keys on the (special) keyboard when 1022 booting the systems 1023 1024- Serial Download Echo Mode: 1025 CONFIG_LOADS_ECHO 1026 If defined to 1, all characters received during a 1027 serial download (using the "loads" command) are 1028 echoed back. This might be needed by some terminal 1029 emulations (like "cu"), but may as well just take 1030 time on others. This setting #define's the initial 1031 value of the "loads_echo" environment variable. 1032 1033- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 1034 CONFIG_KGDB_BAUDRATE 1035 Select one of the baudrates listed in 1036 CONFIG_SYS_BAUDRATE_TABLE, see below. 1037 1038- Monitor Functions: 1039 Monitor commands can be included or excluded 1040 from the build by using the #include files 1041 <config_cmd_all.h> and #undef'ing unwanted 1042 commands, or adding #define's for wanted commands. 1043 1044 The default command configuration includes all commands 1045 except those marked below with a "*". 1046 1047 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 1048 CONFIG_CMD_ASKENV * ask for env variable 1049 CONFIG_CMD_BDI bdinfo 1050 CONFIG_CMD_BEDBUG * Include BedBug Debugger 1051 CONFIG_CMD_BMP * BMP support 1052 CONFIG_CMD_BSP * Board specific commands 1053 CONFIG_CMD_BOOTD bootd 1054 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 1055 CONFIG_CMD_CACHE * icache, dcache 1056 CONFIG_CMD_CLK * clock command support 1057 CONFIG_CMD_CONSOLE coninfo 1058 CONFIG_CMD_CRC32 * crc32 1059 CONFIG_CMD_DATE * support for RTC, date/time... 1060 CONFIG_CMD_DHCP * DHCP support 1061 CONFIG_CMD_DIAG * Diagnostics 1062 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 1063 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 1064 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 1065 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 1066 CONFIG_CMD_DTT * Digital Therm and Thermostat 1067 CONFIG_CMD_ECHO echo arguments 1068 CONFIG_CMD_EDITENV edit env variable 1069 CONFIG_CMD_EEPROM * EEPROM read/write support 1070 CONFIG_CMD_ELF * bootelf, bootvx 1071 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 1072 CONFIG_CMD_ENV_FLAGS * display details about env flags 1073 CONFIG_CMD_ENV_EXISTS * check existence of env variable 1074 CONFIG_CMD_EXPORTENV * export the environment 1075 CONFIG_CMD_EXT2 * ext2 command support 1076 CONFIG_CMD_EXT4 * ext4 command support 1077 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 1078 that work for multiple fs types 1079 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 1080 CONFIG_CMD_SAVEENV saveenv 1081 CONFIG_CMD_FDC * Floppy Disk Support 1082 CONFIG_CMD_FAT * FAT command support 1083 CONFIG_CMD_FLASH flinfo, erase, protect 1084 CONFIG_CMD_FPGA FPGA device initialization support 1085 CONFIG_CMD_FUSE * Device fuse support 1086 CONFIG_CMD_GETTIME * Get time since boot 1087 CONFIG_CMD_GO * the 'go' command (exec code) 1088 CONFIG_CMD_GREPENV * search environment 1089 CONFIG_CMD_HASH * calculate hash / digest 1090 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 1091 CONFIG_CMD_I2C * I2C serial bus support 1092 CONFIG_CMD_IDE * IDE harddisk support 1093 CONFIG_CMD_IMI iminfo 1094 CONFIG_CMD_IMLS List all images found in NOR flash 1095 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1096 CONFIG_CMD_IMMAP * IMMR dump support 1097 CONFIG_CMD_IOTRACE * I/O tracing for debugging 1098 CONFIG_CMD_IMPORTENV * import an environment 1099 CONFIG_CMD_INI * import data from an ini file into the env 1100 CONFIG_CMD_IRQ * irqinfo 1101 CONFIG_CMD_ITEST Integer/string test of 2 values 1102 CONFIG_CMD_JFFS2 * JFFS2 Support 1103 CONFIG_CMD_KGDB * kgdb 1104 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1105 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1106 (169.254.*.*) 1107 CONFIG_CMD_LOADB loadb 1108 CONFIG_CMD_LOADS loads 1109 CONFIG_CMD_MD5SUM * print md5 message digest 1110 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1111 CONFIG_CMD_MEMINFO * Display detailed memory information 1112 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1113 loop, loopw 1114 CONFIG_CMD_MEMTEST * mtest 1115 CONFIG_CMD_MISC Misc functions like sleep etc 1116 CONFIG_CMD_MMC * MMC memory mapped support 1117 CONFIG_CMD_MII * MII utility commands 1118 CONFIG_CMD_MTDPARTS * MTD partition support 1119 CONFIG_CMD_NAND * NAND support 1120 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1121 CONFIG_CMD_NFS NFS support 1122 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1123 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1124 CONFIG_CMD_PCI * pciinfo 1125 CONFIG_CMD_PCMCIA * PCMCIA support 1126 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1127 host 1128 CONFIG_CMD_PORTIO * Port I/O 1129 CONFIG_CMD_READ * Read raw data from partition 1130 CONFIG_CMD_REGINFO * Register dump 1131 CONFIG_CMD_RUN run command in env variable 1132 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1133 CONFIG_CMD_SAVES * save S record dump 1134 CONFIG_CMD_SCSI * SCSI Support 1135 CONFIG_CMD_SDRAM * print SDRAM configuration information 1136 (requires CONFIG_CMD_I2C) 1137 CONFIG_CMD_SETGETDCR Support for DCR Register access 1138 (4xx only) 1139 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1140 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1141 (requires CONFIG_CMD_MEMORY) 1142 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1143 CONFIG_CMD_SOURCE "source" command Support 1144 CONFIG_CMD_SPI * SPI serial bus support 1145 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1146 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1147 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1148 CONFIG_CMD_TIMER * access to the system tick timer 1149 CONFIG_CMD_USB * USB support 1150 CONFIG_CMD_CDP * Cisco Discover Protocol support 1151 CONFIG_CMD_MFSL * Microblaze FSL support 1152 CONFIG_CMD_XIMG Load part of Multi Image 1153 CONFIG_CMD_UUID * Generate random UUID or GUID string 1154 1155 EXAMPLE: If you want all functions except of network 1156 support you can write: 1157 1158 #include "config_cmd_all.h" 1159 #undef CONFIG_CMD_NET 1160 1161 Other Commands: 1162 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1163 1164 Note: Don't enable the "icache" and "dcache" commands 1165 (configuration option CONFIG_CMD_CACHE) unless you know 1166 what you (and your U-Boot users) are doing. Data 1167 cache cannot be enabled on systems like the 8xx or 1168 8260 (where accesses to the IMMR region must be 1169 uncached), and it cannot be disabled on all other 1170 systems where we (mis-) use the data cache to hold an 1171 initial stack and some data. 1172 1173 1174 XXX - this list needs to get updated! 1175 1176- Regular expression support: 1177 CONFIG_REGEX 1178 If this variable is defined, U-Boot is linked against 1179 the SLRE (Super Light Regular Expression) library, 1180 which adds regex support to some commands, as for 1181 example "env grep" and "setexpr". 1182 1183- Device tree: 1184 CONFIG_OF_CONTROL 1185 If this variable is defined, U-Boot will use a device tree 1186 to configure its devices, instead of relying on statically 1187 compiled #defines in the board file. This option is 1188 experimental and only available on a few boards. The device 1189 tree is available in the global data as gd->fdt_blob. 1190 1191 U-Boot needs to get its device tree from somewhere. This can 1192 be done using one of the two options below: 1193 1194 CONFIG_OF_EMBED 1195 If this variable is defined, U-Boot will embed a device tree 1196 binary in its image. This device tree file should be in the 1197 board directory and called <soc>-<board>.dts. The binary file 1198 is then picked up in board_init_f() and made available through 1199 the global data structure as gd->blob. 1200 1201 CONFIG_OF_SEPARATE 1202 If this variable is defined, U-Boot will build a device tree 1203 binary. It will be called u-boot.dtb. Architecture-specific 1204 code will locate it at run-time. Generally this works by: 1205 1206 cat u-boot.bin u-boot.dtb >image.bin 1207 1208 and in fact, U-Boot does this for you, creating a file called 1209 u-boot-dtb.bin which is useful in the common case. You can 1210 still use the individual files if you need something more 1211 exotic. 1212 1213- Watchdog: 1214 CONFIG_WATCHDOG 1215 If this variable is defined, it enables watchdog 1216 support for the SoC. There must be support in the SoC 1217 specific code for a watchdog. For the 8xx and 8260 1218 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1219 register. When supported for a specific SoC is 1220 available, then no further board specific code should 1221 be needed to use it. 1222 1223 CONFIG_HW_WATCHDOG 1224 When using a watchdog circuitry external to the used 1225 SoC, then define this variable and provide board 1226 specific code for the "hw_watchdog_reset" function. 1227 1228 CONFIG_AT91_HW_WDT_TIMEOUT 1229 specify the timeout in seconds. default 2 seconds. 1230 1231- U-Boot Version: 1232 CONFIG_VERSION_VARIABLE 1233 If this variable is defined, an environment variable 1234 named "ver" is created by U-Boot showing the U-Boot 1235 version as printed by the "version" command. 1236 Any change to this variable will be reverted at the 1237 next reset. 1238 1239- Real-Time Clock: 1240 1241 When CONFIG_CMD_DATE is selected, the type of the RTC 1242 has to be selected, too. Define exactly one of the 1243 following options: 1244 1245 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1246 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1247 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1248 CONFIG_RTC_MC146818 - use MC146818 RTC 1249 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1250 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1251 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1252 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1253 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1254 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1255 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1256 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1257 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1258 RV3029 RTC. 1259 1260 Note that if the RTC uses I2C, then the I2C interface 1261 must also be configured. See I2C Support, below. 1262 1263- GPIO Support: 1264 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1265 1266 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1267 chip-ngpio pairs that tell the PCA953X driver the number of 1268 pins supported by a particular chip. 1269 1270 Note that if the GPIO device uses I2C, then the I2C interface 1271 must also be configured. See I2C Support, below. 1272 1273- I/O tracing: 1274 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1275 accesses and can checksum them or write a list of them out 1276 to memory. See the 'iotrace' command for details. This is 1277 useful for testing device drivers since it can confirm that 1278 the driver behaves the same way before and after a code 1279 change. Currently this is supported on sandbox and arm. To 1280 add support for your architecture, add '#include <iotrace.h>' 1281 to the bottom of arch/<arch>/include/asm/io.h and test. 1282 1283 Example output from the 'iotrace stats' command is below. 1284 Note that if the trace buffer is exhausted, the checksum will 1285 still continue to operate. 1286 1287 iotrace is enabled 1288 Start: 10000000 (buffer start address) 1289 Size: 00010000 (buffer size) 1290 Offset: 00000120 (current buffer offset) 1291 Output: 10000120 (start + offset) 1292 Count: 00000018 (number of trace records) 1293 CRC32: 9526fb66 (CRC32 of all trace records) 1294 1295- Timestamp Support: 1296 1297 When CONFIG_TIMESTAMP is selected, the timestamp 1298 (date and time) of an image is printed by image 1299 commands like bootm or iminfo. This option is 1300 automatically enabled when you select CONFIG_CMD_DATE . 1301 1302- Partition Labels (disklabels) Supported: 1303 Zero or more of the following: 1304 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1305 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1306 Intel architecture, USB sticks, etc. 1307 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1308 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1309 bootloader. Note 2TB partition limit; see 1310 disk/part_efi.c 1311 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1312 1313 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1314 CONFIG_CMD_SCSI) you must configure support for at 1315 least one non-MTD partition type as well. 1316 1317- IDE Reset method: 1318 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1319 board configurations files but used nowhere! 1320 1321 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1322 be performed by calling the function 1323 ide_set_reset(int reset) 1324 which has to be defined in a board specific file 1325 1326- ATAPI Support: 1327 CONFIG_ATAPI 1328 1329 Set this to enable ATAPI support. 1330 1331- LBA48 Support 1332 CONFIG_LBA48 1333 1334 Set this to enable support for disks larger than 137GB 1335 Also look at CONFIG_SYS_64BIT_LBA. 1336 Whithout these , LBA48 support uses 32bit variables and will 'only' 1337 support disks up to 2.1TB. 1338 1339 CONFIG_SYS_64BIT_LBA: 1340 When enabled, makes the IDE subsystem use 64bit sector addresses. 1341 Default is 32bit. 1342 1343- SCSI Support: 1344 At the moment only there is only support for the 1345 SYM53C8XX SCSI controller; define 1346 CONFIG_SCSI_SYM53C8XX to enable it. 1347 1348 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1349 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1350 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1351 maximum numbers of LUNs, SCSI ID's and target 1352 devices. 1353 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1354 1355 The environment variable 'scsidevs' is set to the number of 1356 SCSI devices found during the last scan. 1357 1358- NETWORK Support (PCI): 1359 CONFIG_E1000 1360 Support for Intel 8254x/8257x gigabit chips. 1361 1362 CONFIG_E1000_SPI 1363 Utility code for direct access to the SPI bus on Intel 8257x. 1364 This does not do anything useful unless you set at least one 1365 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1366 1367 CONFIG_E1000_SPI_GENERIC 1368 Allow generic access to the SPI bus on the Intel 8257x, for 1369 example with the "sspi" command. 1370 1371 CONFIG_CMD_E1000 1372 Management command for E1000 devices. When used on devices 1373 with SPI support you can reprogram the EEPROM from U-Boot. 1374 1375 CONFIG_EEPRO100 1376 Support for Intel 82557/82559/82559ER chips. 1377 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1378 write routine for first time initialisation. 1379 1380 CONFIG_TULIP 1381 Support for Digital 2114x chips. 1382 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1383 modem chip initialisation (KS8761/QS6611). 1384 1385 CONFIG_NATSEMI 1386 Support for National dp83815 chips. 1387 1388 CONFIG_NS8382X 1389 Support for National dp8382[01] gigabit chips. 1390 1391- NETWORK Support (other): 1392 1393 CONFIG_DRIVER_AT91EMAC 1394 Support for AT91RM9200 EMAC. 1395 1396 CONFIG_RMII 1397 Define this to use reduced MII inteface 1398 1399 CONFIG_DRIVER_AT91EMAC_QUIET 1400 If this defined, the driver is quiet. 1401 The driver doen't show link status messages. 1402 1403 CONFIG_CALXEDA_XGMAC 1404 Support for the Calxeda XGMAC device 1405 1406 CONFIG_LAN91C96 1407 Support for SMSC's LAN91C96 chips. 1408 1409 CONFIG_LAN91C96_BASE 1410 Define this to hold the physical address 1411 of the LAN91C96's I/O space 1412 1413 CONFIG_LAN91C96_USE_32_BIT 1414 Define this to enable 32 bit addressing 1415 1416 CONFIG_SMC91111 1417 Support for SMSC's LAN91C111 chip 1418 1419 CONFIG_SMC91111_BASE 1420 Define this to hold the physical address 1421 of the device (I/O space) 1422 1423 CONFIG_SMC_USE_32_BIT 1424 Define this if data bus is 32 bits 1425 1426 CONFIG_SMC_USE_IOFUNCS 1427 Define this to use i/o functions instead of macros 1428 (some hardware wont work with macros) 1429 1430 CONFIG_DRIVER_TI_EMAC 1431 Support for davinci emac 1432 1433 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1434 Define this if you have more then 3 PHYs. 1435 1436 CONFIG_FTGMAC100 1437 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1438 1439 CONFIG_FTGMAC100_EGIGA 1440 Define this to use GE link update with gigabit PHY. 1441 Define this if FTGMAC100 is connected to gigabit PHY. 1442 If your system has 10/100 PHY only, it might not occur 1443 wrong behavior. Because PHY usually return timeout or 1444 useless data when polling gigabit status and gigabit 1445 control registers. This behavior won't affect the 1446 correctnessof 10/100 link speed update. 1447 1448 CONFIG_SMC911X 1449 Support for SMSC's LAN911x and LAN921x chips 1450 1451 CONFIG_SMC911X_BASE 1452 Define this to hold the physical address 1453 of the device (I/O space) 1454 1455 CONFIG_SMC911X_32_BIT 1456 Define this if data bus is 32 bits 1457 1458 CONFIG_SMC911X_16_BIT 1459 Define this if data bus is 16 bits. If your processor 1460 automatically converts one 32 bit word to two 16 bit 1461 words you may also try CONFIG_SMC911X_32_BIT. 1462 1463 CONFIG_SH_ETHER 1464 Support for Renesas on-chip Ethernet controller 1465 1466 CONFIG_SH_ETHER_USE_PORT 1467 Define the number of ports to be used 1468 1469 CONFIG_SH_ETHER_PHY_ADDR 1470 Define the ETH PHY's address 1471 1472 CONFIG_SH_ETHER_CACHE_WRITEBACK 1473 If this option is set, the driver enables cache flush. 1474 1475- PWM Support: 1476 CONFIG_PWM_IMX 1477 Support for PWM modul on the imx6. 1478 1479- TPM Support: 1480 CONFIG_TPM 1481 Support TPM devices. 1482 1483 CONFIG_TPM_TIS_I2C 1484 Support for i2c bus TPM devices. Only one device 1485 per system is supported at this time. 1486 1487 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1488 Define the burst count bytes upper limit 1489 1490 CONFIG_TPM_ATMEL_TWI 1491 Support for Atmel TWI TPM device. Requires I2C support. 1492 1493 CONFIG_TPM_TIS_LPC 1494 Support for generic parallel port TPM devices. Only one device 1495 per system is supported at this time. 1496 1497 CONFIG_TPM_TIS_BASE_ADDRESS 1498 Base address where the generic TPM device is mapped 1499 to. Contemporary x86 systems usually map it at 1500 0xfed40000. 1501 1502 CONFIG_CMD_TPM 1503 Add tpm monitor functions. 1504 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1505 provides monitor access to authorized functions. 1506 1507 CONFIG_TPM 1508 Define this to enable the TPM support library which provides 1509 functional interfaces to some TPM commands. 1510 Requires support for a TPM device. 1511 1512 CONFIG_TPM_AUTH_SESSIONS 1513 Define this to enable authorized functions in the TPM library. 1514 Requires CONFIG_TPM and CONFIG_SHA1. 1515 1516- USB Support: 1517 At the moment only the UHCI host controller is 1518 supported (PIP405, MIP405, MPC5200); define 1519 CONFIG_USB_UHCI to enable it. 1520 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1521 and define CONFIG_USB_STORAGE to enable the USB 1522 storage devices. 1523 Note: 1524 Supported are USB Keyboards and USB Floppy drives 1525 (TEAC FD-05PUB). 1526 MPC5200 USB requires additional defines: 1527 CONFIG_USB_CLOCK 1528 for 528 MHz Clock: 0x0001bbbb 1529 CONFIG_PSC3_USB 1530 for USB on PSC3 1531 CONFIG_USB_CONFIG 1532 for differential drivers: 0x00001000 1533 for single ended drivers: 0x00005000 1534 for differential drivers on PSC3: 0x00000100 1535 for single ended drivers on PSC3: 0x00004100 1536 CONFIG_SYS_USB_EVENT_POLL 1537 May be defined to allow interrupt polling 1538 instead of using asynchronous interrupts 1539 1540 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1541 txfilltuning field in the EHCI controller on reset. 1542 1543 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1544 HW module registers. 1545 1546- USB Device: 1547 Define the below if you wish to use the USB console. 1548 Once firmware is rebuilt from a serial console issue the 1549 command "setenv stdin usbtty; setenv stdout usbtty" and 1550 attach your USB cable. The Unix command "dmesg" should print 1551 it has found a new device. The environment variable usbtty 1552 can be set to gserial or cdc_acm to enable your device to 1553 appear to a USB host as a Linux gserial device or a 1554 Common Device Class Abstract Control Model serial device. 1555 If you select usbtty = gserial you should be able to enumerate 1556 a Linux host by 1557 # modprobe usbserial vendor=0xVendorID product=0xProductID 1558 else if using cdc_acm, simply setting the environment 1559 variable usbtty to be cdc_acm should suffice. The following 1560 might be defined in YourBoardName.h 1561 1562 CONFIG_USB_DEVICE 1563 Define this to build a UDC device 1564 1565 CONFIG_USB_TTY 1566 Define this to have a tty type of device available to 1567 talk to the UDC device 1568 1569 CONFIG_USBD_HS 1570 Define this to enable the high speed support for usb 1571 device and usbtty. If this feature is enabled, a routine 1572 int is_usbd_high_speed(void) 1573 also needs to be defined by the driver to dynamically poll 1574 whether the enumeration has succeded at high speed or full 1575 speed. 1576 1577 CONFIG_SYS_CONSOLE_IS_IN_ENV 1578 Define this if you want stdin, stdout &/or stderr to 1579 be set to usbtty. 1580 1581 mpc8xx: 1582 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1583 Derive USB clock from external clock "blah" 1584 - CONFIG_SYS_USB_EXTC_CLK 0x02 1585 1586 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1587 Derive USB clock from brgclk 1588 - CONFIG_SYS_USB_BRG_CLK 0x04 1589 1590 If you have a USB-IF assigned VendorID then you may wish to 1591 define your own vendor specific values either in BoardName.h 1592 or directly in usbd_vendor_info.h. If you don't define 1593 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1594 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1595 should pretend to be a Linux device to it's target host. 1596 1597 CONFIG_USBD_MANUFACTURER 1598 Define this string as the name of your company for 1599 - CONFIG_USBD_MANUFACTURER "my company" 1600 1601 CONFIG_USBD_PRODUCT_NAME 1602 Define this string as the name of your product 1603 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1604 1605 CONFIG_USBD_VENDORID 1606 Define this as your assigned Vendor ID from the USB 1607 Implementors Forum. This *must* be a genuine Vendor ID 1608 to avoid polluting the USB namespace. 1609 - CONFIG_USBD_VENDORID 0xFFFF 1610 1611 CONFIG_USBD_PRODUCTID 1612 Define this as the unique Product ID 1613 for your device 1614 - CONFIG_USBD_PRODUCTID 0xFFFF 1615 1616- ULPI Layer Support: 1617 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1618 the generic ULPI layer. The generic layer accesses the ULPI PHY 1619 via the platform viewport, so you need both the genric layer and 1620 the viewport enabled. Currently only Chipidea/ARC based 1621 viewport is supported. 1622 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1623 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1624 If your ULPI phy needs a different reference clock than the 1625 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1626 the appropriate value in Hz. 1627 1628- MMC Support: 1629 The MMC controller on the Intel PXA is supported. To 1630 enable this define CONFIG_MMC. The MMC can be 1631 accessed from the boot prompt by mapping the device 1632 to physical memory similar to flash. Command line is 1633 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1634 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1635 1636 CONFIG_SH_MMCIF 1637 Support for Renesas on-chip MMCIF controller 1638 1639 CONFIG_SH_MMCIF_ADDR 1640 Define the base address of MMCIF registers 1641 1642 CONFIG_SH_MMCIF_CLK 1643 Define the clock frequency for MMCIF 1644 1645 CONFIG_GENERIC_MMC 1646 Enable the generic MMC driver 1647 1648 CONFIG_SUPPORT_EMMC_BOOT 1649 Enable some additional features of the eMMC boot partitions. 1650 1651 CONFIG_SUPPORT_EMMC_RPMB 1652 Enable the commands for reading, writing and programming the 1653 key for the Replay Protection Memory Block partition in eMMC. 1654 1655- USB Device Firmware Update (DFU) class support: 1656 CONFIG_USB_FUNCTION_DFU 1657 This enables the USB portion of the DFU USB class 1658 1659 CONFIG_CMD_DFU 1660 This enables the command "dfu" which is used to have 1661 U-Boot create a DFU class device via USB. This command 1662 requires that the "dfu_alt_info" environment variable be 1663 set and define the alt settings to expose to the host. 1664 1665 CONFIG_DFU_MMC 1666 This enables support for exposing (e)MMC devices via DFU. 1667 1668 CONFIG_DFU_NAND 1669 This enables support for exposing NAND devices via DFU. 1670 1671 CONFIG_DFU_RAM 1672 This enables support for exposing RAM via DFU. 1673 Note: DFU spec refer to non-volatile memory usage, but 1674 allow usages beyond the scope of spec - here RAM usage, 1675 one that would help mostly the developer. 1676 1677 CONFIG_SYS_DFU_DATA_BUF_SIZE 1678 Dfu transfer uses a buffer before writing data to the 1679 raw storage device. Make the size (in bytes) of this buffer 1680 configurable. The size of this buffer is also configurable 1681 through the "dfu_bufsiz" environment variable. 1682 1683 CONFIG_SYS_DFU_MAX_FILE_SIZE 1684 When updating files rather than the raw storage device, 1685 we use a static buffer to copy the file into and then write 1686 the buffer once we've been given the whole file. Define 1687 this to the maximum filesize (in bytes) for the buffer. 1688 Default is 4 MiB if undefined. 1689 1690 DFU_DEFAULT_POLL_TIMEOUT 1691 Poll timeout [ms], is the timeout a device can send to the 1692 host. The host must wait for this timeout before sending 1693 a subsequent DFU_GET_STATUS request to the device. 1694 1695 DFU_MANIFEST_POLL_TIMEOUT 1696 Poll timeout [ms], which the device sends to the host when 1697 entering dfuMANIFEST state. Host waits this timeout, before 1698 sending again an USB request to the device. 1699 1700- USB Device Android Fastboot support: 1701 CONFIG_USB_FUNCTION_FASTBOOT 1702 This enables the USB part of the fastboot gadget 1703 1704 CONFIG_CMD_FASTBOOT 1705 This enables the command "fastboot" which enables the Android 1706 fastboot mode for the platform's USB device. Fastboot is a USB 1707 protocol for downloading images, flashing and device control 1708 used on Android devices. 1709 See doc/README.android-fastboot for more information. 1710 1711 CONFIG_ANDROID_BOOT_IMAGE 1712 This enables support for booting images which use the Android 1713 image format header. 1714 1715 CONFIG_FASTBOOT_BUF_ADDR 1716 The fastboot protocol requires a large memory buffer for 1717 downloads. Define this to the starting RAM address to use for 1718 downloaded images. 1719 1720 CONFIG_FASTBOOT_BUF_SIZE 1721 The fastboot protocol requires a large memory buffer for 1722 downloads. This buffer should be as large as possible for a 1723 platform. Define this to the size available RAM for fastboot. 1724 1725 CONFIG_FASTBOOT_FLASH 1726 The fastboot protocol includes a "flash" command for writing 1727 the downloaded image to a non-volatile storage device. Define 1728 this to enable the "fastboot flash" command. 1729 1730 CONFIG_FASTBOOT_FLASH_MMC_DEV 1731 The fastboot "flash" command requires additional information 1732 regarding the non-volatile storage device. Define this to 1733 the eMMC device that fastboot should use to store the image. 1734 1735 CONFIG_FASTBOOT_GPT_NAME 1736 The fastboot "flash" command supports writing the downloaded 1737 image to the Protective MBR and the Primary GUID Partition 1738 Table. (Additionally, this downloaded image is post-processed 1739 to generate and write the Backup GUID Partition Table.) 1740 This occurs when the specified "partition name" on the 1741 "fastboot flash" command line matches this value. 1742 Default is GPT_ENTRY_NAME (currently "gpt") if undefined. 1743 1744- Journaling Flash filesystem support: 1745 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1746 CONFIG_JFFS2_NAND_DEV 1747 Define these for a default partition on a NAND device 1748 1749 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1750 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1751 Define these for a default partition on a NOR device 1752 1753 CONFIG_SYS_JFFS_CUSTOM_PART 1754 Define this to create an own partition. You have to provide a 1755 function struct part_info* jffs2_part_info(int part_num) 1756 1757 If you define only one JFFS2 partition you may also want to 1758 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1759 to disable the command chpart. This is the default when you 1760 have not defined a custom partition 1761 1762- FAT(File Allocation Table) filesystem write function support: 1763 CONFIG_FAT_WRITE 1764 1765 Define this to enable support for saving memory data as a 1766 file in FAT formatted partition. 1767 1768 This will also enable the command "fatwrite" enabling the 1769 user to write files to FAT. 1770 1771CBFS (Coreboot Filesystem) support 1772 CONFIG_CMD_CBFS 1773 1774 Define this to enable support for reading from a Coreboot 1775 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1776 and cbfsload. 1777 1778- FAT(File Allocation Table) filesystem cluster size: 1779 CONFIG_FS_FAT_MAX_CLUSTSIZE 1780 1781 Define the max cluster size for fat operations else 1782 a default value of 65536 will be defined. 1783 1784- Keyboard Support: 1785 CONFIG_ISA_KEYBOARD 1786 1787 Define this to enable standard (PC-Style) keyboard 1788 support 1789 1790 CONFIG_I8042_KBD 1791 Standard PC keyboard driver with US (is default) and 1792 GERMAN key layout (switch via environment 'keymap=de') support. 1793 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1794 for cfb_console. Supports cursor blinking. 1795 1796 CONFIG_CROS_EC_KEYB 1797 Enables a Chrome OS keyboard using the CROS_EC interface. 1798 This uses CROS_EC to communicate with a second microcontroller 1799 which provides key scans on request. 1800 1801- Video support: 1802 CONFIG_VIDEO 1803 1804 Define this to enable video support (for output to 1805 video). 1806 1807 CONFIG_VIDEO_CT69000 1808 1809 Enable Chips & Technologies 69000 Video chip 1810 1811 CONFIG_VIDEO_SMI_LYNXEM 1812 Enable Silicon Motion SMI 712/710/810 Video chip. The 1813 video output is selected via environment 'videoout' 1814 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1815 assumed. 1816 1817 For the CT69000 and SMI_LYNXEM drivers, videomode is 1818 selected via environment 'videomode'. Two different ways 1819 are possible: 1820 - "videomode=num" 'num' is a standard LiLo mode numbers. 1821 Following standard modes are supported (* is default): 1822 1823 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1824 -------------+--------------------------------------------- 1825 8 bits | 0x301* 0x303 0x305 0x161 0x307 1826 15 bits | 0x310 0x313 0x316 0x162 0x319 1827 16 bits | 0x311 0x314 0x317 0x163 0x31A 1828 24 bits | 0x312 0x315 0x318 ? 0x31B 1829 -------------+--------------------------------------------- 1830 (i.e. setenv videomode 317; saveenv; reset;) 1831 1832 - "videomode=bootargs" all the video parameters are parsed 1833 from the bootargs. (See drivers/video/videomodes.c) 1834 1835 1836 CONFIG_VIDEO_SED13806 1837 Enable Epson SED13806 driver. This driver supports 8bpp 1838 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1839 or CONFIG_VIDEO_SED13806_16BPP 1840 1841 CONFIG_FSL_DIU_FB 1842 Enable the Freescale DIU video driver. Reference boards for 1843 SOCs that have a DIU should define this macro to enable DIU 1844 support, and should also define these other macros: 1845 1846 CONFIG_SYS_DIU_ADDR 1847 CONFIG_VIDEO 1848 CONFIG_CMD_BMP 1849 CONFIG_CFB_CONSOLE 1850 CONFIG_VIDEO_SW_CURSOR 1851 CONFIG_VGA_AS_SINGLE_DEVICE 1852 CONFIG_VIDEO_LOGO 1853 CONFIG_VIDEO_BMP_LOGO 1854 1855 The DIU driver will look for the 'video-mode' environment 1856 variable, and if defined, enable the DIU as a console during 1857 boot. See the documentation file README.video for a 1858 description of this variable. 1859 1860 1861- Keyboard Support: 1862 CONFIG_KEYBOARD 1863 1864 Define this to enable a custom keyboard support. 1865 This simply calls drv_keyboard_init() which must be 1866 defined in your board-specific files. 1867 The only board using this so far is RBC823. 1868 1869- LCD Support: CONFIG_LCD 1870 1871 Define this to enable LCD support (for output to LCD 1872 display); also select one of the supported displays 1873 by defining one of these: 1874 1875 CONFIG_ATMEL_LCD: 1876 1877 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1878 1879 CONFIG_NEC_NL6448AC33: 1880 1881 NEC NL6448AC33-18. Active, color, single scan. 1882 1883 CONFIG_NEC_NL6448BC20 1884 1885 NEC NL6448BC20-08. 6.5", 640x480. 1886 Active, color, single scan. 1887 1888 CONFIG_NEC_NL6448BC33_54 1889 1890 NEC NL6448BC33-54. 10.4", 640x480. 1891 Active, color, single scan. 1892 1893 CONFIG_SHARP_16x9 1894 1895 Sharp 320x240. Active, color, single scan. 1896 It isn't 16x9, and I am not sure what it is. 1897 1898 CONFIG_SHARP_LQ64D341 1899 1900 Sharp LQ64D341 display, 640x480. 1901 Active, color, single scan. 1902 1903 CONFIG_HLD1045 1904 1905 HLD1045 display, 640x480. 1906 Active, color, single scan. 1907 1908 CONFIG_OPTREX_BW 1909 1910 Optrex CBL50840-2 NF-FW 99 22 M5 1911 or 1912 Hitachi LMG6912RPFC-00T 1913 or 1914 Hitachi SP14Q002 1915 1916 320x240. Black & white. 1917 1918 Normally display is black on white background; define 1919 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1920 1921 CONFIG_LCD_ALIGNMENT 1922 1923 Normally the LCD is page-aligned (typically 4KB). If this is 1924 defined then the LCD will be aligned to this value instead. 1925 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1926 here, since it is cheaper to change data cache settings on 1927 a per-section basis. 1928 1929 CONFIG_CONSOLE_SCROLL_LINES 1930 1931 When the console need to be scrolled, this is the number of 1932 lines to scroll by. It defaults to 1. Increasing this makes 1933 the console jump but can help speed up operation when scrolling 1934 is slow. 1935 1936 CONFIG_LCD_ROTATION 1937 1938 Sometimes, for example if the display is mounted in portrait 1939 mode or even if it's mounted landscape but rotated by 180degree, 1940 we need to rotate our content of the display relative to the 1941 framebuffer, so that user can read the messages which are 1942 printed out. 1943 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1944 initialized with a given rotation from "vl_rot" out of 1945 "vidinfo_t" which is provided by the board specific code. 1946 The value for vl_rot is coded as following (matching to 1947 fbcon=rotate:<n> linux-kernel commandline): 1948 0 = no rotation respectively 0 degree 1949 1 = 90 degree rotation 1950 2 = 180 degree rotation 1951 3 = 270 degree rotation 1952 1953 If CONFIG_LCD_ROTATION is not defined, the console will be 1954 initialized with 0degree rotation. 1955 1956 CONFIG_LCD_BMP_RLE8 1957 1958 Support drawing of RLE8-compressed bitmaps on the LCD. 1959 1960 CONFIG_I2C_EDID 1961 1962 Enables an 'i2c edid' command which can read EDID 1963 information over I2C from an attached LCD display. 1964 1965- Splash Screen Support: CONFIG_SPLASH_SCREEN 1966 1967 If this option is set, the environment is checked for 1968 a variable "splashimage". If found, the usual display 1969 of logo, copyright and system information on the LCD 1970 is suppressed and the BMP image at the address 1971 specified in "splashimage" is loaded instead. The 1972 console is redirected to the "nulldev", too. This 1973 allows for a "silent" boot where a splash screen is 1974 loaded very quickly after power-on. 1975 1976 CONFIG_SPLASHIMAGE_GUARD 1977 1978 If this option is set, then U-Boot will prevent the environment 1979 variable "splashimage" from being set to a problematic address 1980 (see README.displaying-bmps). 1981 This option is useful for targets where, due to alignment 1982 restrictions, an improperly aligned BMP image will cause a data 1983 abort. If you think you will not have problems with unaligned 1984 accesses (for example because your toolchain prevents them) 1985 there is no need to set this option. 1986 1987 CONFIG_SPLASH_SCREEN_ALIGN 1988 1989 If this option is set the splash image can be freely positioned 1990 on the screen. Environment variable "splashpos" specifies the 1991 position as "x,y". If a positive number is given it is used as 1992 number of pixel from left/top. If a negative number is given it 1993 is used as number of pixel from right/bottom. You can also 1994 specify 'm' for centering the image. 1995 1996 Example: 1997 setenv splashpos m,m 1998 => image at center of screen 1999 2000 setenv splashpos 30,20 2001 => image at x = 30 and y = 20 2002 2003 setenv splashpos -10,m 2004 => vertically centered image 2005 at x = dspWidth - bmpWidth - 9 2006 2007- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 2008 2009 If this option is set, additionally to standard BMP 2010 images, gzipped BMP images can be displayed via the 2011 splashscreen support or the bmp command. 2012 2013- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 2014 2015 If this option is set, 8-bit RLE compressed BMP images 2016 can be displayed via the splashscreen support or the 2017 bmp command. 2018 2019- Do compressing for memory range: 2020 CONFIG_CMD_ZIP 2021 2022 If this option is set, it would use zlib deflate method 2023 to compress the specified memory at its best effort. 2024 2025- Compression support: 2026 CONFIG_GZIP 2027 2028 Enabled by default to support gzip compressed images. 2029 2030 CONFIG_BZIP2 2031 2032 If this option is set, support for bzip2 compressed 2033 images is included. If not, only uncompressed and gzip 2034 compressed images are supported. 2035 2036 NOTE: the bzip2 algorithm requires a lot of RAM, so 2037 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 2038 be at least 4MB. 2039 2040 CONFIG_LZMA 2041 2042 If this option is set, support for lzma compressed 2043 images is included. 2044 2045 Note: The LZMA algorithm adds between 2 and 4KB of code and it 2046 requires an amount of dynamic memory that is given by the 2047 formula: 2048 2049 (1846 + 768 << (lc + lp)) * sizeof(uint16) 2050 2051 Where lc and lp stand for, respectively, Literal context bits 2052 and Literal pos bits. 2053 2054 This value is upper-bounded by 14MB in the worst case. Anyway, 2055 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 2056 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 2057 a very small buffer. 2058 2059 Use the lzmainfo tool to determinate the lc and lp values and 2060 then calculate the amount of needed dynamic memory (ensuring 2061 the appropriate CONFIG_SYS_MALLOC_LEN value). 2062 2063 CONFIG_LZO 2064 2065 If this option is set, support for LZO compressed images 2066 is included. 2067 2068- MII/PHY support: 2069 CONFIG_PHY_ADDR 2070 2071 The address of PHY on MII bus. 2072 2073 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 2074 2075 The clock frequency of the MII bus 2076 2077 CONFIG_PHY_GIGE 2078 2079 If this option is set, support for speed/duplex 2080 detection of gigabit PHY is included. 2081 2082 CONFIG_PHY_RESET_DELAY 2083 2084 Some PHY like Intel LXT971A need extra delay after 2085 reset before any MII register access is possible. 2086 For such PHY, set this option to the usec delay 2087 required. (minimum 300usec for LXT971A) 2088 2089 CONFIG_PHY_CMD_DELAY (ppc4xx) 2090 2091 Some PHY like Intel LXT971A need extra delay after 2092 command issued before MII status register can be read 2093 2094- IP address: 2095 CONFIG_IPADDR 2096 2097 Define a default value for the IP address to use for 2098 the default Ethernet interface, in case this is not 2099 determined through e.g. bootp. 2100 (Environment variable "ipaddr") 2101 2102- Server IP address: 2103 CONFIG_SERVERIP 2104 2105 Defines a default value for the IP address of a TFTP 2106 server to contact when using the "tftboot" command. 2107 (Environment variable "serverip") 2108 2109 CONFIG_KEEP_SERVERADDR 2110 2111 Keeps the server's MAC address, in the env 'serveraddr' 2112 for passing to bootargs (like Linux's netconsole option) 2113 2114- Gateway IP address: 2115 CONFIG_GATEWAYIP 2116 2117 Defines a default value for the IP address of the 2118 default router where packets to other networks are 2119 sent to. 2120 (Environment variable "gatewayip") 2121 2122- Subnet mask: 2123 CONFIG_NETMASK 2124 2125 Defines a default value for the subnet mask (or 2126 routing prefix) which is used to determine if an IP 2127 address belongs to the local subnet or needs to be 2128 forwarded through a router. 2129 (Environment variable "netmask") 2130 2131- Multicast TFTP Mode: 2132 CONFIG_MCAST_TFTP 2133 2134 Defines whether you want to support multicast TFTP as per 2135 rfc-2090; for example to work with atftp. Lets lots of targets 2136 tftp down the same boot image concurrently. Note: the Ethernet 2137 driver in use must provide a function: mcast() to join/leave a 2138 multicast group. 2139 2140- BOOTP Recovery Mode: 2141 CONFIG_BOOTP_RANDOM_DELAY 2142 2143 If you have many targets in a network that try to 2144 boot using BOOTP, you may want to avoid that all 2145 systems send out BOOTP requests at precisely the same 2146 moment (which would happen for instance at recovery 2147 from a power failure, when all systems will try to 2148 boot, thus flooding the BOOTP server. Defining 2149 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 2150 inserted before sending out BOOTP requests. The 2151 following delays are inserted then: 2152 2153 1st BOOTP request: delay 0 ... 1 sec 2154 2nd BOOTP request: delay 0 ... 2 sec 2155 3rd BOOTP request: delay 0 ... 4 sec 2156 4th and following 2157 BOOTP requests: delay 0 ... 8 sec 2158 2159 CONFIG_BOOTP_ID_CACHE_SIZE 2160 2161 BOOTP packets are uniquely identified using a 32-bit ID. The 2162 server will copy the ID from client requests to responses and 2163 U-Boot will use this to determine if it is the destination of 2164 an incoming response. Some servers will check that addresses 2165 aren't in use before handing them out (usually using an ARP 2166 ping) and therefore take up to a few hundred milliseconds to 2167 respond. Network congestion may also influence the time it 2168 takes for a response to make it back to the client. If that 2169 time is too long, U-Boot will retransmit requests. In order 2170 to allow earlier responses to still be accepted after these 2171 retransmissions, U-Boot's BOOTP client keeps a small cache of 2172 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 2173 cache. The default is to keep IDs for up to four outstanding 2174 requests. Increasing this will allow U-Boot to accept offers 2175 from a BOOTP client in networks with unusually high latency. 2176 2177- DHCP Advanced Options: 2178 You can fine tune the DHCP functionality by defining 2179 CONFIG_BOOTP_* symbols: 2180 2181 CONFIG_BOOTP_SUBNETMASK 2182 CONFIG_BOOTP_GATEWAY 2183 CONFIG_BOOTP_HOSTNAME 2184 CONFIG_BOOTP_NISDOMAIN 2185 CONFIG_BOOTP_BOOTPATH 2186 CONFIG_BOOTP_BOOTFILESIZE 2187 CONFIG_BOOTP_DNS 2188 CONFIG_BOOTP_DNS2 2189 CONFIG_BOOTP_SEND_HOSTNAME 2190 CONFIG_BOOTP_NTPSERVER 2191 CONFIG_BOOTP_TIMEOFFSET 2192 CONFIG_BOOTP_VENDOREX 2193 CONFIG_BOOTP_MAY_FAIL 2194 2195 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2196 environment variable, not the BOOTP server. 2197 2198 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2199 after the configured retry count, the call will fail 2200 instead of starting over. This can be used to fail over 2201 to Link-local IP address configuration if the DHCP server 2202 is not available. 2203 2204 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2205 serverip from a DHCP server, it is possible that more 2206 than one DNS serverip is offered to the client. 2207 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2208 serverip will be stored in the additional environment 2209 variable "dnsip2". The first DNS serverip is always 2210 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2211 is defined. 2212 2213 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2214 to do a dynamic update of a DNS server. To do this, they 2215 need the hostname of the DHCP requester. 2216 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2217 of the "hostname" environment variable is passed as 2218 option 12 to the DHCP server. 2219 2220 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2221 2222 A 32bit value in microseconds for a delay between 2223 receiving a "DHCP Offer" and sending the "DHCP Request". 2224 This fixes a problem with certain DHCP servers that don't 2225 respond 100% of the time to a "DHCP request". E.g. On an 2226 AT91RM9200 processor running at 180MHz, this delay needed 2227 to be *at least* 15,000 usec before a Windows Server 2003 2228 DHCP server would reply 100% of the time. I recommend at 2229 least 50,000 usec to be safe. The alternative is to hope 2230 that one of the retries will be successful but note that 2231 the DHCP timeout and retry process takes a longer than 2232 this delay. 2233 2234 - Link-local IP address negotiation: 2235 Negotiate with other link-local clients on the local network 2236 for an address that doesn't require explicit configuration. 2237 This is especially useful if a DHCP server cannot be guaranteed 2238 to exist in all environments that the device must operate. 2239 2240 See doc/README.link-local for more information. 2241 2242 - CDP Options: 2243 CONFIG_CDP_DEVICE_ID 2244 2245 The device id used in CDP trigger frames. 2246 2247 CONFIG_CDP_DEVICE_ID_PREFIX 2248 2249 A two character string which is prefixed to the MAC address 2250 of the device. 2251 2252 CONFIG_CDP_PORT_ID 2253 2254 A printf format string which contains the ascii name of 2255 the port. Normally is set to "eth%d" which sets 2256 eth0 for the first Ethernet, eth1 for the second etc. 2257 2258 CONFIG_CDP_CAPABILITIES 2259 2260 A 32bit integer which indicates the device capabilities; 2261 0x00000010 for a normal host which does not forwards. 2262 2263 CONFIG_CDP_VERSION 2264 2265 An ascii string containing the version of the software. 2266 2267 CONFIG_CDP_PLATFORM 2268 2269 An ascii string containing the name of the platform. 2270 2271 CONFIG_CDP_TRIGGER 2272 2273 A 32bit integer sent on the trigger. 2274 2275 CONFIG_CDP_POWER_CONSUMPTION 2276 2277 A 16bit integer containing the power consumption of the 2278 device in .1 of milliwatts. 2279 2280 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2281 2282 A byte containing the id of the VLAN. 2283 2284- Status LED: CONFIG_STATUS_LED 2285 2286 Several configurations allow to display the current 2287 status using a LED. For instance, the LED will blink 2288 fast while running U-Boot code, stop blinking as 2289 soon as a reply to a BOOTP request was received, and 2290 start blinking slow once the Linux kernel is running 2291 (supported by a status LED driver in the Linux 2292 kernel). Defining CONFIG_STATUS_LED enables this 2293 feature in U-Boot. 2294 2295 Additional options: 2296 2297 CONFIG_GPIO_LED 2298 The status LED can be connected to a GPIO pin. 2299 In such cases, the gpio_led driver can be used as a 2300 status LED backend implementation. Define CONFIG_GPIO_LED 2301 to include the gpio_led driver in the U-Boot binary. 2302 2303 CONFIG_GPIO_LED_INVERTED_TABLE 2304 Some GPIO connected LEDs may have inverted polarity in which 2305 case the GPIO high value corresponds to LED off state and 2306 GPIO low value corresponds to LED on state. 2307 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2308 with a list of GPIO LEDs that have inverted polarity. 2309 2310- CAN Support: CONFIG_CAN_DRIVER 2311 2312 Defining CONFIG_CAN_DRIVER enables CAN driver support 2313 on those systems that support this (optional) 2314 feature, like the TQM8xxL modules. 2315 2316- I2C Support: CONFIG_SYS_I2C 2317 2318 This enable the NEW i2c subsystem, and will allow you to use 2319 i2c commands at the u-boot command line (as long as you set 2320 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2321 based realtime clock chips or other i2c devices. See 2322 common/cmd_i2c.c for a description of the command line 2323 interface. 2324 2325 ported i2c driver to the new framework: 2326 - drivers/i2c/soft_i2c.c: 2327 - activate first bus with CONFIG_SYS_I2C_SOFT define 2328 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2329 for defining speed and slave address 2330 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2331 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2332 for defining speed and slave address 2333 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2334 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2335 for defining speed and slave address 2336 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2337 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2338 for defining speed and slave address 2339 2340 - drivers/i2c/fsl_i2c.c: 2341 - activate i2c driver with CONFIG_SYS_I2C_FSL 2342 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2343 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2344 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2345 bus. 2346 - If your board supports a second fsl i2c bus, define 2347 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2348 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2349 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2350 second bus. 2351 2352 - drivers/i2c/tegra_i2c.c: 2353 - activate this driver with CONFIG_SYS_I2C_TEGRA 2354 - This driver adds 4 i2c buses with a fix speed from 2355 100000 and the slave addr 0! 2356 2357 - drivers/i2c/ppc4xx_i2c.c 2358 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2359 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2360 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2361 2362 - drivers/i2c/i2c_mxc.c 2363 - activate this driver with CONFIG_SYS_I2C_MXC 2364 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2365 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2366 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2367 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2368 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2369 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2370 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2371 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2372 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2373 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2374 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2375 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2376 If those defines are not set, default value is 100000 2377 for speed, and 0 for slave. 2378 2379 - drivers/i2c/rcar_i2c.c: 2380 - activate this driver with CONFIG_SYS_I2C_RCAR 2381 - This driver adds 4 i2c buses 2382 2383 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2384 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2385 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2386 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2387 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2388 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2389 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2390 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2391 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2392 2393 - drivers/i2c/sh_i2c.c: 2394 - activate this driver with CONFIG_SYS_I2C_SH 2395 - This driver adds from 2 to 5 i2c buses 2396 2397 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2398 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2399 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2400 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2401 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2402 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2403 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2404 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2405 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2406 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2407 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2408 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2409 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2410 2411 - drivers/i2c/omap24xx_i2c.c 2412 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2413 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2414 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2415 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2416 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2417 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2418 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2419 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2420 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2421 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2422 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2423 2424 - drivers/i2c/zynq_i2c.c 2425 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2426 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2427 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2428 2429 - drivers/i2c/s3c24x0_i2c.c: 2430 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2431 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2432 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2433 with a fix speed from 100000 and the slave addr 0! 2434 2435 - drivers/i2c/ihs_i2c.c 2436 - activate this driver with CONFIG_SYS_I2C_IHS 2437 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2438 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2439 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2440 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2441 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2442 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2443 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2444 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2445 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2446 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2447 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2448 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2449 2450 additional defines: 2451 2452 CONFIG_SYS_NUM_I2C_BUSES 2453 Hold the number of i2c buses you want to use. If you 2454 don't use/have i2c muxes on your i2c bus, this 2455 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2456 omit this define. 2457 2458 CONFIG_SYS_I2C_DIRECT_BUS 2459 define this, if you don't use i2c muxes on your hardware. 2460 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2461 omit this define. 2462 2463 CONFIG_SYS_I2C_MAX_HOPS 2464 define how many muxes are maximal consecutively connected 2465 on one i2c bus. If you not use i2c muxes, omit this 2466 define. 2467 2468 CONFIG_SYS_I2C_BUSES 2469 hold a list of buses you want to use, only used if 2470 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2471 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2472 CONFIG_SYS_NUM_I2C_BUSES = 9: 2473 2474 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2475 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2476 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2477 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2478 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2479 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2480 {1, {I2C_NULL_HOP}}, \ 2481 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2482 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2483 } 2484 2485 which defines 2486 bus 0 on adapter 0 without a mux 2487 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2488 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2489 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2490 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2491 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2492 bus 6 on adapter 1 without a mux 2493 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2494 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2495 2496 If you do not have i2c muxes on your board, omit this define. 2497 2498- Legacy I2C Support: CONFIG_HARD_I2C 2499 2500 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2501 provides the following compelling advantages: 2502 2503 - more than one i2c adapter is usable 2504 - approved multibus support 2505 - better i2c mux support 2506 2507 ** Please consider updating your I2C driver now. ** 2508 2509 These enable legacy I2C serial bus commands. Defining 2510 CONFIG_HARD_I2C will include the appropriate I2C driver 2511 for the selected CPU. 2512 2513 This will allow you to use i2c commands at the u-boot 2514 command line (as long as you set CONFIG_CMD_I2C in 2515 CONFIG_COMMANDS) and communicate with i2c based realtime 2516 clock chips. See common/cmd_i2c.c for a description of the 2517 command line interface. 2518 2519 CONFIG_HARD_I2C selects a hardware I2C controller. 2520 2521 There are several other quantities that must also be 2522 defined when you define CONFIG_HARD_I2C. 2523 2524 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2525 to be the frequency (in Hz) at which you wish your i2c bus 2526 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2527 the CPU's i2c node address). 2528 2529 Now, the u-boot i2c code for the mpc8xx 2530 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2531 and so its address should therefore be cleared to 0 (See, 2532 eg, MPC823e User's Manual p.16-473). So, set 2533 CONFIG_SYS_I2C_SLAVE to 0. 2534 2535 CONFIG_SYS_I2C_INIT_MPC5XXX 2536 2537 When a board is reset during an i2c bus transfer 2538 chips might think that the current transfer is still 2539 in progress. Reset the slave devices by sending start 2540 commands until the slave device responds. 2541 2542 That's all that's required for CONFIG_HARD_I2C. 2543 2544 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2545 then the following macros need to be defined (examples are 2546 from include/configs/lwmon.h): 2547 2548 I2C_INIT 2549 2550 (Optional). Any commands necessary to enable the I2C 2551 controller or configure ports. 2552 2553 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2554 2555 I2C_PORT 2556 2557 (Only for MPC8260 CPU). The I/O port to use (the code 2558 assumes both bits are on the same port). Valid values 2559 are 0..3 for ports A..D. 2560 2561 I2C_ACTIVE 2562 2563 The code necessary to make the I2C data line active 2564 (driven). If the data line is open collector, this 2565 define can be null. 2566 2567 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2568 2569 I2C_TRISTATE 2570 2571 The code necessary to make the I2C data line tri-stated 2572 (inactive). If the data line is open collector, this 2573 define can be null. 2574 2575 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2576 2577 I2C_READ 2578 2579 Code that returns true if the I2C data line is high, 2580 false if it is low. 2581 2582 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2583 2584 I2C_SDA(bit) 2585 2586 If <bit> is true, sets the I2C data line high. If it 2587 is false, it clears it (low). 2588 2589 eg: #define I2C_SDA(bit) \ 2590 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2591 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2592 2593 I2C_SCL(bit) 2594 2595 If <bit> is true, sets the I2C clock line high. If it 2596 is false, it clears it (low). 2597 2598 eg: #define I2C_SCL(bit) \ 2599 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2600 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2601 2602 I2C_DELAY 2603 2604 This delay is invoked four times per clock cycle so this 2605 controls the rate of data transfer. The data rate thus 2606 is 1 / (I2C_DELAY * 4). Often defined to be something 2607 like: 2608 2609 #define I2C_DELAY udelay(2) 2610 2611 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2612 2613 If your arch supports the generic GPIO framework (asm/gpio.h), 2614 then you may alternatively define the two GPIOs that are to be 2615 used as SCL / SDA. Any of the previous I2C_xxx macros will 2616 have GPIO-based defaults assigned to them as appropriate. 2617 2618 You should define these to the GPIO value as given directly to 2619 the generic GPIO functions. 2620 2621 CONFIG_SYS_I2C_INIT_BOARD 2622 2623 When a board is reset during an i2c bus transfer 2624 chips might think that the current transfer is still 2625 in progress. On some boards it is possible to access 2626 the i2c SCLK line directly, either by using the 2627 processor pin as a GPIO or by having a second pin 2628 connected to the bus. If this option is defined a 2629 custom i2c_init_board() routine in boards/xxx/board.c 2630 is run early in the boot sequence. 2631 2632 CONFIG_SYS_I2C_BOARD_LATE_INIT 2633 2634 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2635 defined a custom i2c_board_late_init() routine in 2636 boards/xxx/board.c is run AFTER the operations in i2c_init() 2637 is completed. This callpoint can be used to unreset i2c bus 2638 using CPU i2c controller register accesses for CPUs whose i2c 2639 controller provide such a method. It is called at the end of 2640 i2c_init() to allow i2c_init operations to setup the i2c bus 2641 controller on the CPU (e.g. setting bus speed & slave address). 2642 2643 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2644 2645 This option enables configuration of bi_iic_fast[] flags 2646 in u-boot bd_info structure based on u-boot environment 2647 variable "i2cfast". (see also i2cfast) 2648 2649 CONFIG_I2C_MULTI_BUS 2650 2651 This option allows the use of multiple I2C buses, each of which 2652 must have a controller. At any point in time, only one bus is 2653 active. To switch to a different bus, use the 'i2c dev' command. 2654 Note that bus numbering is zero-based. 2655 2656 CONFIG_SYS_I2C_NOPROBES 2657 2658 This option specifies a list of I2C devices that will be skipped 2659 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2660 is set, specify a list of bus-device pairs. Otherwise, specify 2661 a 1D array of device addresses 2662 2663 e.g. 2664 #undef CONFIG_I2C_MULTI_BUS 2665 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2666 2667 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2668 2669 #define CONFIG_I2C_MULTI_BUS 2670 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2671 2672 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2673 2674 CONFIG_SYS_SPD_BUS_NUM 2675 2676 If defined, then this indicates the I2C bus number for DDR SPD. 2677 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2678 2679 CONFIG_SYS_RTC_BUS_NUM 2680 2681 If defined, then this indicates the I2C bus number for the RTC. 2682 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2683 2684 CONFIG_SYS_DTT_BUS_NUM 2685 2686 If defined, then this indicates the I2C bus number for the DTT. 2687 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2688 2689 CONFIG_SYS_I2C_DTT_ADDR: 2690 2691 If defined, specifies the I2C address of the DTT device. 2692 If not defined, then U-Boot uses predefined value for 2693 specified DTT device. 2694 2695 CONFIG_SOFT_I2C_READ_REPEATED_START 2696 2697 defining this will force the i2c_read() function in 2698 the soft_i2c driver to perform an I2C repeated start 2699 between writing the address pointer and reading the 2700 data. If this define is omitted the default behaviour 2701 of doing a stop-start sequence will be used. Most I2C 2702 devices can use either method, but some require one or 2703 the other. 2704 2705- SPI Support: CONFIG_SPI 2706 2707 Enables SPI driver (so far only tested with 2708 SPI EEPROM, also an instance works with Crystal A/D and 2709 D/As on the SACSng board) 2710 2711 CONFIG_SH_SPI 2712 2713 Enables the driver for SPI controller on SuperH. Currently 2714 only SH7757 is supported. 2715 2716 CONFIG_SPI_X 2717 2718 Enables extended (16-bit) SPI EEPROM addressing. 2719 (symmetrical to CONFIG_I2C_X) 2720 2721 CONFIG_SOFT_SPI 2722 2723 Enables a software (bit-bang) SPI driver rather than 2724 using hardware support. This is a general purpose 2725 driver that only requires three general I/O port pins 2726 (two outputs, one input) to function. If this is 2727 defined, the board configuration must define several 2728 SPI configuration items (port pins to use, etc). For 2729 an example, see include/configs/sacsng.h. 2730 2731 CONFIG_HARD_SPI 2732 2733 Enables a hardware SPI driver for general-purpose reads 2734 and writes. As with CONFIG_SOFT_SPI, the board configuration 2735 must define a list of chip-select function pointers. 2736 Currently supported on some MPC8xxx processors. For an 2737 example, see include/configs/mpc8349emds.h. 2738 2739 CONFIG_MXC_SPI 2740 2741 Enables the driver for the SPI controllers on i.MX and MXC 2742 SoCs. Currently i.MX31/35/51 are supported. 2743 2744 CONFIG_SYS_SPI_MXC_WAIT 2745 Timeout for waiting until spi transfer completed. 2746 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2747 2748- FPGA Support: CONFIG_FPGA 2749 2750 Enables FPGA subsystem. 2751 2752 CONFIG_FPGA_<vendor> 2753 2754 Enables support for specific chip vendors. 2755 (ALTERA, XILINX) 2756 2757 CONFIG_FPGA_<family> 2758 2759 Enables support for FPGA family. 2760 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2761 2762 CONFIG_FPGA_COUNT 2763 2764 Specify the number of FPGA devices to support. 2765 2766 CONFIG_CMD_FPGA_LOADMK 2767 2768 Enable support for fpga loadmk command 2769 2770 CONFIG_CMD_FPGA_LOADP 2771 2772 Enable support for fpga loadp command - load partial bitstream 2773 2774 CONFIG_CMD_FPGA_LOADBP 2775 2776 Enable support for fpga loadbp command - load partial bitstream 2777 (Xilinx only) 2778 2779 CONFIG_SYS_FPGA_PROG_FEEDBACK 2780 2781 Enable printing of hash marks during FPGA configuration. 2782 2783 CONFIG_SYS_FPGA_CHECK_BUSY 2784 2785 Enable checks on FPGA configuration interface busy 2786 status by the configuration function. This option 2787 will require a board or device specific function to 2788 be written. 2789 2790 CONFIG_FPGA_DELAY 2791 2792 If defined, a function that provides delays in the FPGA 2793 configuration driver. 2794 2795 CONFIG_SYS_FPGA_CHECK_CTRLC 2796 Allow Control-C to interrupt FPGA configuration 2797 2798 CONFIG_SYS_FPGA_CHECK_ERROR 2799 2800 Check for configuration errors during FPGA bitfile 2801 loading. For example, abort during Virtex II 2802 configuration if the INIT_B line goes low (which 2803 indicated a CRC error). 2804 2805 CONFIG_SYS_FPGA_WAIT_INIT 2806 2807 Maximum time to wait for the INIT_B line to de-assert 2808 after PROB_B has been de-asserted during a Virtex II 2809 FPGA configuration sequence. The default time is 500 2810 ms. 2811 2812 CONFIG_SYS_FPGA_WAIT_BUSY 2813 2814 Maximum time to wait for BUSY to de-assert during 2815 Virtex II FPGA configuration. The default is 5 ms. 2816 2817 CONFIG_SYS_FPGA_WAIT_CONFIG 2818 2819 Time to wait after FPGA configuration. The default is 2820 200 ms. 2821 2822- Configuration Management: 2823 CONFIG_BUILD_TARGET 2824 2825 Some SoCs need special image types (e.g. U-Boot binary 2826 with a special header) as build targets. By defining 2827 CONFIG_BUILD_TARGET in the SoC / board header, this 2828 special image will be automatically built upon calling 2829 make / MAKEALL. 2830 2831 CONFIG_IDENT_STRING 2832 2833 If defined, this string will be added to the U-Boot 2834 version information (U_BOOT_VERSION) 2835 2836- Vendor Parameter Protection: 2837 2838 U-Boot considers the values of the environment 2839 variables "serial#" (Board Serial Number) and 2840 "ethaddr" (Ethernet Address) to be parameters that 2841 are set once by the board vendor / manufacturer, and 2842 protects these variables from casual modification by 2843 the user. Once set, these variables are read-only, 2844 and write or delete attempts are rejected. You can 2845 change this behaviour: 2846 2847 If CONFIG_ENV_OVERWRITE is #defined in your config 2848 file, the write protection for vendor parameters is 2849 completely disabled. Anybody can change or delete 2850 these parameters. 2851 2852 Alternatively, if you define _both_ an ethaddr in the 2853 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2854 Ethernet address is installed in the environment, 2855 which can be changed exactly ONCE by the user. [The 2856 serial# is unaffected by this, i. e. it remains 2857 read-only.] 2858 2859 The same can be accomplished in a more flexible way 2860 for any variable by configuring the type of access 2861 to allow for those variables in the ".flags" variable 2862 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2863 2864- Protected RAM: 2865 CONFIG_PRAM 2866 2867 Define this variable to enable the reservation of 2868 "protected RAM", i. e. RAM which is not overwritten 2869 by U-Boot. Define CONFIG_PRAM to hold the number of 2870 kB you want to reserve for pRAM. You can overwrite 2871 this default value by defining an environment 2872 variable "pram" to the number of kB you want to 2873 reserve. Note that the board info structure will 2874 still show the full amount of RAM. If pRAM is 2875 reserved, a new environment variable "mem" will 2876 automatically be defined to hold the amount of 2877 remaining RAM in a form that can be passed as boot 2878 argument to Linux, for instance like that: 2879 2880 setenv bootargs ... mem=\${mem} 2881 saveenv 2882 2883 This way you can tell Linux not to use this memory, 2884 either, which results in a memory region that will 2885 not be affected by reboots. 2886 2887 *WARNING* If your board configuration uses automatic 2888 detection of the RAM size, you must make sure that 2889 this memory test is non-destructive. So far, the 2890 following board configurations are known to be 2891 "pRAM-clean": 2892 2893 IVMS8, IVML24, SPD8xx, TQM8xxL, 2894 HERMES, IP860, RPXlite, LWMON, 2895 FLAGADM, TQM8260 2896 2897- Access to physical memory region (> 4GB) 2898 Some basic support is provided for operations on memory not 2899 normally accessible to U-Boot - e.g. some architectures 2900 support access to more than 4GB of memory on 32-bit 2901 machines using physical address extension or similar. 2902 Define CONFIG_PHYSMEM to access this basic support, which 2903 currently only supports clearing the memory. 2904 2905- Error Recovery: 2906 CONFIG_PANIC_HANG 2907 2908 Define this variable to stop the system in case of a 2909 fatal error, so that you have to reset it manually. 2910 This is probably NOT a good idea for an embedded 2911 system where you want the system to reboot 2912 automatically as fast as possible, but it may be 2913 useful during development since you can try to debug 2914 the conditions that lead to the situation. 2915 2916 CONFIG_NET_RETRY_COUNT 2917 2918 This variable defines the number of retries for 2919 network operations like ARP, RARP, TFTP, or BOOTP 2920 before giving up the operation. If not defined, a 2921 default value of 5 is used. 2922 2923 CONFIG_ARP_TIMEOUT 2924 2925 Timeout waiting for an ARP reply in milliseconds. 2926 2927 CONFIG_NFS_TIMEOUT 2928 2929 Timeout in milliseconds used in NFS protocol. 2930 If you encounter "ERROR: Cannot umount" in nfs command, 2931 try longer timeout such as 2932 #define CONFIG_NFS_TIMEOUT 10000UL 2933 2934- Command Interpreter: 2935 CONFIG_AUTO_COMPLETE 2936 2937 Enable auto completion of commands using TAB. 2938 2939 CONFIG_SYS_PROMPT_HUSH_PS2 2940 2941 This defines the secondary prompt string, which is 2942 printed when the command interpreter needs more input 2943 to complete a command. Usually "> ". 2944 2945 Note: 2946 2947 In the current implementation, the local variables 2948 space and global environment variables space are 2949 separated. Local variables are those you define by 2950 simply typing `name=value'. To access a local 2951 variable later on, you have write `$name' or 2952 `${name}'; to execute the contents of a variable 2953 directly type `$name' at the command prompt. 2954 2955 Global environment variables are those you use 2956 setenv/printenv to work with. To run a command stored 2957 in such a variable, you need to use the run command, 2958 and you must not use the '$' sign to access them. 2959 2960 To store commands and special characters in a 2961 variable, please use double quotation marks 2962 surrounding the whole text of the variable, instead 2963 of the backslashes before semicolons and special 2964 symbols. 2965 2966- Command Line Editing and History: 2967 CONFIG_CMDLINE_EDITING 2968 2969 Enable editing and History functions for interactive 2970 command line input operations 2971 2972- Default Environment: 2973 CONFIG_EXTRA_ENV_SETTINGS 2974 2975 Define this to contain any number of null terminated 2976 strings (variable = value pairs) that will be part of 2977 the default environment compiled into the boot image. 2978 2979 For example, place something like this in your 2980 board's config file: 2981 2982 #define CONFIG_EXTRA_ENV_SETTINGS \ 2983 "myvar1=value1\0" \ 2984 "myvar2=value2\0" 2985 2986 Warning: This method is based on knowledge about the 2987 internal format how the environment is stored by the 2988 U-Boot code. This is NOT an official, exported 2989 interface! Although it is unlikely that this format 2990 will change soon, there is no guarantee either. 2991 You better know what you are doing here. 2992 2993 Note: overly (ab)use of the default environment is 2994 discouraged. Make sure to check other ways to preset 2995 the environment like the "source" command or the 2996 boot command first. 2997 2998 CONFIG_ENV_VARS_UBOOT_CONFIG 2999 3000 Define this in order to add variables describing the 3001 U-Boot build configuration to the default environment. 3002 These will be named arch, cpu, board, vendor, and soc. 3003 3004 Enabling this option will cause the following to be defined: 3005 3006 - CONFIG_SYS_ARCH 3007 - CONFIG_SYS_CPU 3008 - CONFIG_SYS_BOARD 3009 - CONFIG_SYS_VENDOR 3010 - CONFIG_SYS_SOC 3011 3012 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 3013 3014 Define this in order to add variables describing certain 3015 run-time determined information about the hardware to the 3016 environment. These will be named board_name, board_rev. 3017 3018 CONFIG_DELAY_ENVIRONMENT 3019 3020 Normally the environment is loaded when the board is 3021 initialised so that it is available to U-Boot. This inhibits 3022 that so that the environment is not available until 3023 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 3024 this is instead controlled by the value of 3025 /config/load-environment. 3026 3027- Parallel Flash support: 3028 CONFIG_SYS_NO_FLASH 3029 3030 Traditionally U-boot was run on systems with parallel NOR 3031 flash. This option is used to disable support for parallel NOR 3032 flash. This option should be defined if the board does not have 3033 parallel flash. 3034 3035 If this option is not defined one of the generic flash drivers 3036 (e.g. CONFIG_FLASH_CFI_DRIVER or CONFIG_ST_SMI) must be 3037 selected or the board must provide an implementation of the 3038 flash API (see include/flash.h). 3039 3040- DataFlash Support: 3041 CONFIG_HAS_DATAFLASH 3042 3043 Defining this option enables DataFlash features and 3044 allows to read/write in Dataflash via the standard 3045 commands cp, md... 3046 3047- Serial Flash support 3048 CONFIG_CMD_SF 3049 3050 Defining this option enables SPI flash commands 3051 'sf probe/read/write/erase/update'. 3052 3053 Usage requires an initial 'probe' to define the serial 3054 flash parameters, followed by read/write/erase/update 3055 commands. 3056 3057 The following defaults may be provided by the platform 3058 to handle the common case when only a single serial 3059 flash is present on the system. 3060 3061 CONFIG_SF_DEFAULT_BUS Bus identifier 3062 CONFIG_SF_DEFAULT_CS Chip-select 3063 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 3064 CONFIG_SF_DEFAULT_SPEED in Hz 3065 3066 CONFIG_CMD_SF_TEST 3067 3068 Define this option to include a destructive SPI flash 3069 test ('sf test'). 3070 3071 CONFIG_SF_DUAL_FLASH Dual flash memories 3072 3073 Define this option to use dual flash support where two flash 3074 memories can be connected with a given cs line. 3075 Currently Xilinx Zynq qspi supports these type of connections. 3076 3077- SystemACE Support: 3078 CONFIG_SYSTEMACE 3079 3080 Adding this option adds support for Xilinx SystemACE 3081 chips attached via some sort of local bus. The address 3082 of the chip must also be defined in the 3083 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 3084 3085 #define CONFIG_SYSTEMACE 3086 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 3087 3088 When SystemACE support is added, the "ace" device type 3089 becomes available to the fat commands, i.e. fatls. 3090 3091- TFTP Fixed UDP Port: 3092 CONFIG_TFTP_PORT 3093 3094 If this is defined, the environment variable tftpsrcp 3095 is used to supply the TFTP UDP source port value. 3096 If tftpsrcp isn't defined, the normal pseudo-random port 3097 number generator is used. 3098 3099 Also, the environment variable tftpdstp is used to supply 3100 the TFTP UDP destination port value. If tftpdstp isn't 3101 defined, the normal port 69 is used. 3102 3103 The purpose for tftpsrcp is to allow a TFTP server to 3104 blindly start the TFTP transfer using the pre-configured 3105 target IP address and UDP port. This has the effect of 3106 "punching through" the (Windows XP) firewall, allowing 3107 the remainder of the TFTP transfer to proceed normally. 3108 A better solution is to properly configure the firewall, 3109 but sometimes that is not allowed. 3110 3111- Hashing support: 3112 CONFIG_CMD_HASH 3113 3114 This enables a generic 'hash' command which can produce 3115 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 3116 3117 CONFIG_HASH_VERIFY 3118 3119 Enable the hash verify command (hash -v). This adds to code 3120 size a little. 3121 3122 CONFIG_SHA1 - This option enables support of hashing using SHA1 3123 algorithm. The hash is calculated in software. 3124 CONFIG_SHA256 - This option enables support of hashing using 3125 SHA256 algorithm. The hash is calculated in software. 3126 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 3127 for SHA1/SHA256 hashing. 3128 This affects the 'hash' command and also the 3129 hash_lookup_algo() function. 3130 CONFIG_SHA_PROG_HW_ACCEL - This option enables 3131 hardware-acceleration for SHA1/SHA256 progressive hashing. 3132 Data can be streamed in a block at a time and the hashing 3133 is performed in hardware. 3134 3135 Note: There is also a sha1sum command, which should perhaps 3136 be deprecated in favour of 'hash sha1'. 3137 3138- Freescale i.MX specific commands: 3139 CONFIG_CMD_HDMIDETECT 3140 This enables 'hdmidet' command which returns true if an 3141 HDMI monitor is detected. This command is i.MX 6 specific. 3142 3143 CONFIG_CMD_BMODE 3144 This enables the 'bmode' (bootmode) command for forcing 3145 a boot from specific media. 3146 3147 This is useful for forcing the ROM's usb downloader to 3148 activate upon a watchdog reset which is nice when iterating 3149 on U-Boot. Using the reset button or running bmode normal 3150 will set it back to normal. This command currently 3151 supports i.MX53 and i.MX6. 3152 3153- Signing support: 3154 CONFIG_RSA 3155 3156 This enables the RSA algorithm used for FIT image verification 3157 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 3158 3159 The Modular Exponentiation algorithm in RSA is implemented using 3160 driver model. So CONFIG_DM needs to be enabled by default for this 3161 library to function. 3162 3163 The signing part is build into mkimage regardless of this 3164 option. The software based modular exponentiation is built into 3165 mkimage irrespective of this option. 3166 3167- bootcount support: 3168 CONFIG_BOOTCOUNT_LIMIT 3169 3170 This enables the bootcounter support, see: 3171 http://www.denx.de/wiki/DULG/UBootBootCountLimit 3172 3173 CONFIG_AT91SAM9XE 3174 enable special bootcounter support on at91sam9xe based boards. 3175 CONFIG_BLACKFIN 3176 enable special bootcounter support on blackfin based boards. 3177 CONFIG_SOC_DA8XX 3178 enable special bootcounter support on da850 based boards. 3179 CONFIG_BOOTCOUNT_RAM 3180 enable support for the bootcounter in RAM 3181 CONFIG_BOOTCOUNT_I2C 3182 enable support for the bootcounter on an i2c (like RTC) device. 3183 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 3184 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 3185 the bootcounter. 3186 CONFIG_BOOTCOUNT_ALEN = address len 3187 3188- Show boot progress: 3189 CONFIG_SHOW_BOOT_PROGRESS 3190 3191 Defining this option allows to add some board- 3192 specific code (calling a user-provided function 3193 "show_boot_progress(int)") that enables you to show 3194 the system's boot progress on some display (for 3195 example, some LED's) on your board. At the moment, 3196 the following checkpoints are implemented: 3197 3198 3199Legacy uImage format: 3200 3201 Arg Where When 3202 1 common/cmd_bootm.c before attempting to boot an image 3203 -1 common/cmd_bootm.c Image header has bad magic number 3204 2 common/cmd_bootm.c Image header has correct magic number 3205 -2 common/cmd_bootm.c Image header has bad checksum 3206 3 common/cmd_bootm.c Image header has correct checksum 3207 -3 common/cmd_bootm.c Image data has bad checksum 3208 4 common/cmd_bootm.c Image data has correct checksum 3209 -4 common/cmd_bootm.c Image is for unsupported architecture 3210 5 common/cmd_bootm.c Architecture check OK 3211 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3212 6 common/cmd_bootm.c Image Type check OK 3213 -6 common/cmd_bootm.c gunzip uncompression error 3214 -7 common/cmd_bootm.c Unimplemented compression type 3215 7 common/cmd_bootm.c Uncompression OK 3216 8 common/cmd_bootm.c No uncompress/copy overwrite error 3217 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3218 3219 9 common/image.c Start initial ramdisk verification 3220 -10 common/image.c Ramdisk header has bad magic number 3221 -11 common/image.c Ramdisk header has bad checksum 3222 10 common/image.c Ramdisk header is OK 3223 -12 common/image.c Ramdisk data has bad checksum 3224 11 common/image.c Ramdisk data has correct checksum 3225 12 common/image.c Ramdisk verification complete, start loading 3226 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3227 13 common/image.c Start multifile image verification 3228 14 common/image.c No initial ramdisk, no multifile, continue. 3229 3230 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3231 3232 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3233 -31 post/post.c POST test failed, detected by post_output_backlog() 3234 -32 post/post.c POST test failed, detected by post_run_single() 3235 3236 34 common/cmd_doc.c before loading a Image from a DOC device 3237 -35 common/cmd_doc.c Bad usage of "doc" command 3238 35 common/cmd_doc.c correct usage of "doc" command 3239 -36 common/cmd_doc.c No boot device 3240 36 common/cmd_doc.c correct boot device 3241 -37 common/cmd_doc.c Unknown Chip ID on boot device 3242 37 common/cmd_doc.c correct chip ID found, device available 3243 -38 common/cmd_doc.c Read Error on boot device 3244 38 common/cmd_doc.c reading Image header from DOC device OK 3245 -39 common/cmd_doc.c Image header has bad magic number 3246 39 common/cmd_doc.c Image header has correct magic number 3247 -40 common/cmd_doc.c Error reading Image from DOC device 3248 40 common/cmd_doc.c Image header has correct magic number 3249 41 common/cmd_ide.c before loading a Image from a IDE device 3250 -42 common/cmd_ide.c Bad usage of "ide" command 3251 42 common/cmd_ide.c correct usage of "ide" command 3252 -43 common/cmd_ide.c No boot device 3253 43 common/cmd_ide.c boot device found 3254 -44 common/cmd_ide.c Device not available 3255 44 common/cmd_ide.c Device available 3256 -45 common/cmd_ide.c wrong partition selected 3257 45 common/cmd_ide.c partition selected 3258 -46 common/cmd_ide.c Unknown partition table 3259 46 common/cmd_ide.c valid partition table found 3260 -47 common/cmd_ide.c Invalid partition type 3261 47 common/cmd_ide.c correct partition type 3262 -48 common/cmd_ide.c Error reading Image Header on boot device 3263 48 common/cmd_ide.c reading Image Header from IDE device OK 3264 -49 common/cmd_ide.c Image header has bad magic number 3265 49 common/cmd_ide.c Image header has correct magic number 3266 -50 common/cmd_ide.c Image header has bad checksum 3267 50 common/cmd_ide.c Image header has correct checksum 3268 -51 common/cmd_ide.c Error reading Image from IDE device 3269 51 common/cmd_ide.c reading Image from IDE device OK 3270 52 common/cmd_nand.c before loading a Image from a NAND device 3271 -53 common/cmd_nand.c Bad usage of "nand" command 3272 53 common/cmd_nand.c correct usage of "nand" command 3273 -54 common/cmd_nand.c No boot device 3274 54 common/cmd_nand.c boot device found 3275 -55 common/cmd_nand.c Unknown Chip ID on boot device 3276 55 common/cmd_nand.c correct chip ID found, device available 3277 -56 common/cmd_nand.c Error reading Image Header on boot device 3278 56 common/cmd_nand.c reading Image Header from NAND device OK 3279 -57 common/cmd_nand.c Image header has bad magic number 3280 57 common/cmd_nand.c Image header has correct magic number 3281 -58 common/cmd_nand.c Error reading Image from NAND device 3282 58 common/cmd_nand.c reading Image from NAND device OK 3283 3284 -60 common/env_common.c Environment has a bad CRC, using default 3285 3286 64 net/eth.c starting with Ethernet configuration. 3287 -64 net/eth.c no Ethernet found. 3288 65 net/eth.c Ethernet found. 3289 3290 -80 common/cmd_net.c usage wrong 3291 80 common/cmd_net.c before calling net_loop() 3292 -81 common/cmd_net.c some error in net_loop() occurred 3293 81 common/cmd_net.c net_loop() back without error 3294 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3295 82 common/cmd_net.c trying automatic boot 3296 83 common/cmd_net.c running "source" command 3297 -83 common/cmd_net.c some error in automatic boot or "source" command 3298 84 common/cmd_net.c end without errors 3299 3300FIT uImage format: 3301 3302 Arg Where When 3303 100 common/cmd_bootm.c Kernel FIT Image has correct format 3304 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3305 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3306 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3307 102 common/cmd_bootm.c Kernel unit name specified 3308 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3309 103 common/cmd_bootm.c Found configuration node 3310 104 common/cmd_bootm.c Got kernel subimage node offset 3311 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3312 105 common/cmd_bootm.c Kernel subimage hash verification OK 3313 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3314 106 common/cmd_bootm.c Architecture check OK 3315 -106 common/cmd_bootm.c Kernel subimage has wrong type 3316 107 common/cmd_bootm.c Kernel subimage type OK 3317 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3318 108 common/cmd_bootm.c Got kernel subimage data/size 3319 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3320 -109 common/cmd_bootm.c Can't get kernel subimage type 3321 -110 common/cmd_bootm.c Can't get kernel subimage comp 3322 -111 common/cmd_bootm.c Can't get kernel subimage os 3323 -112 common/cmd_bootm.c Can't get kernel subimage load address 3324 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3325 3326 120 common/image.c Start initial ramdisk verification 3327 -120 common/image.c Ramdisk FIT image has incorrect format 3328 121 common/image.c Ramdisk FIT image has correct format 3329 122 common/image.c No ramdisk subimage unit name, using configuration 3330 -122 common/image.c Can't get configuration for ramdisk subimage 3331 123 common/image.c Ramdisk unit name specified 3332 -124 common/image.c Can't get ramdisk subimage node offset 3333 125 common/image.c Got ramdisk subimage node offset 3334 -125 common/image.c Ramdisk subimage hash verification failed 3335 126 common/image.c Ramdisk subimage hash verification OK 3336 -126 common/image.c Ramdisk subimage for unsupported architecture 3337 127 common/image.c Architecture check OK 3338 -127 common/image.c Can't get ramdisk subimage data/size 3339 128 common/image.c Got ramdisk subimage data/size 3340 129 common/image.c Can't get ramdisk load address 3341 -129 common/image.c Got ramdisk load address 3342 3343 -130 common/cmd_doc.c Incorrect FIT image format 3344 131 common/cmd_doc.c FIT image format OK 3345 3346 -140 common/cmd_ide.c Incorrect FIT image format 3347 141 common/cmd_ide.c FIT image format OK 3348 3349 -150 common/cmd_nand.c Incorrect FIT image format 3350 151 common/cmd_nand.c FIT image format OK 3351 3352- legacy image format: 3353 CONFIG_IMAGE_FORMAT_LEGACY 3354 enables the legacy image format support in U-Boot. 3355 3356 Default: 3357 enabled if CONFIG_FIT_SIGNATURE is not defined. 3358 3359 CONFIG_DISABLE_IMAGE_LEGACY 3360 disable the legacy image format 3361 3362 This define is introduced, as the legacy image format is 3363 enabled per default for backward compatibility. 3364 3365- FIT image support: 3366 CONFIG_FIT 3367 Enable support for the FIT uImage format. 3368 3369 CONFIG_FIT_BEST_MATCH 3370 When no configuration is explicitly selected, default to the 3371 one whose fdt's compatibility field best matches that of 3372 U-Boot itself. A match is considered "best" if it matches the 3373 most specific compatibility entry of U-Boot's fdt's root node. 3374 The order of entries in the configuration's fdt is ignored. 3375 3376 CONFIG_FIT_SIGNATURE 3377 This option enables signature verification of FIT uImages, 3378 using a hash signed and verified using RSA. If 3379 CONFIG_SHA_PROG_HW_ACCEL is defined, i.e support for progressive 3380 hashing is available using hardware, RSA library will use it. 3381 See doc/uImage.FIT/signature.txt for more details. 3382 3383 WARNING: When relying on signed FIT images with required 3384 signature check the legacy image format is default 3385 disabled. If a board need legacy image format support 3386 enable this through CONFIG_IMAGE_FORMAT_LEGACY 3387 3388 CONFIG_FIT_DISABLE_SHA256 3389 Supporting SHA256 hashes has quite an impact on binary size. 3390 For constrained systems sha256 hash support can be disabled 3391 with this option. 3392 3393- Standalone program support: 3394 CONFIG_STANDALONE_LOAD_ADDR 3395 3396 This option defines a board specific value for the 3397 address where standalone program gets loaded, thus 3398 overwriting the architecture dependent default 3399 settings. 3400 3401- Frame Buffer Address: 3402 CONFIG_FB_ADDR 3403 3404 Define CONFIG_FB_ADDR if you want to use specific 3405 address for frame buffer. This is typically the case 3406 when using a graphics controller has separate video 3407 memory. U-Boot will then place the frame buffer at 3408 the given address instead of dynamically reserving it 3409 in system RAM by calling lcd_setmem(), which grabs 3410 the memory for the frame buffer depending on the 3411 configured panel size. 3412 3413 Please see board_init_f function. 3414 3415- Automatic software updates via TFTP server 3416 CONFIG_UPDATE_TFTP 3417 CONFIG_UPDATE_TFTP_CNT_MAX 3418 CONFIG_UPDATE_TFTP_MSEC_MAX 3419 3420 These options enable and control the auto-update feature; 3421 for a more detailed description refer to doc/README.update. 3422 3423- MTD Support (mtdparts command, UBI support) 3424 CONFIG_MTD_DEVICE 3425 3426 Adds the MTD device infrastructure from the Linux kernel. 3427 Needed for mtdparts command support. 3428 3429 CONFIG_MTD_PARTITIONS 3430 3431 Adds the MTD partitioning infrastructure from the Linux 3432 kernel. Needed for UBI support. 3433 3434- UBI support 3435 CONFIG_CMD_UBI 3436 3437 Adds commands for interacting with MTD partitions formatted 3438 with the UBI flash translation layer 3439 3440 Requires also defining CONFIG_RBTREE 3441 3442 CONFIG_UBI_SILENCE_MSG 3443 3444 Make the verbose messages from UBI stop printing. This leaves 3445 warnings and errors enabled. 3446 3447 3448 CONFIG_MTD_UBI_WL_THRESHOLD 3449 This parameter defines the maximum difference between the highest 3450 erase counter value and the lowest erase counter value of eraseblocks 3451 of UBI devices. When this threshold is exceeded, UBI starts performing 3452 wear leveling by means of moving data from eraseblock with low erase 3453 counter to eraseblocks with high erase counter. 3454 3455 The default value should be OK for SLC NAND flashes, NOR flashes and 3456 other flashes which have eraseblock life-cycle 100000 or more. 3457 However, in case of MLC NAND flashes which typically have eraseblock 3458 life-cycle less than 10000, the threshold should be lessened (e.g., 3459 to 128 or 256, although it does not have to be power of 2). 3460 3461 default: 4096 3462 3463 CONFIG_MTD_UBI_BEB_LIMIT 3464 This option specifies the maximum bad physical eraseblocks UBI 3465 expects on the MTD device (per 1024 eraseblocks). If the 3466 underlying flash does not admit of bad eraseblocks (e.g. NOR 3467 flash), this value is ignored. 3468 3469 NAND datasheets often specify the minimum and maximum NVM 3470 (Number of Valid Blocks) for the flashes' endurance lifetime. 3471 The maximum expected bad eraseblocks per 1024 eraseblocks 3472 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3473 which gives 20 for most NANDs (MaxNVB is basically the total 3474 count of eraseblocks on the chip). 3475 3476 To put it differently, if this value is 20, UBI will try to 3477 reserve about 1.9% of physical eraseblocks for bad blocks 3478 handling. And that will be 1.9% of eraseblocks on the entire 3479 NAND chip, not just the MTD partition UBI attaches. This means 3480 that if you have, say, a NAND flash chip admits maximum 40 bad 3481 eraseblocks, and it is split on two MTD partitions of the same 3482 size, UBI will reserve 40 eraseblocks when attaching a 3483 partition. 3484 3485 default: 20 3486 3487 CONFIG_MTD_UBI_FASTMAP 3488 Fastmap is a mechanism which allows attaching an UBI device 3489 in nearly constant time. Instead of scanning the whole MTD device it 3490 only has to locate a checkpoint (called fastmap) on the device. 3491 The on-flash fastmap contains all information needed to attach 3492 the device. Using fastmap makes only sense on large devices where 3493 attaching by scanning takes long. UBI will not automatically install 3494 a fastmap on old images, but you can set the UBI parameter 3495 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3496 that fastmap-enabled images are still usable with UBI implementations 3497 without fastmap support. On typical flash devices the whole fastmap 3498 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3499 3500 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3501 Set this parameter to enable fastmap automatically on images 3502 without a fastmap. 3503 default: 0 3504 3505- UBIFS support 3506 CONFIG_CMD_UBIFS 3507 3508 Adds commands for interacting with UBI volumes formatted as 3509 UBIFS. UBIFS is read-only in u-boot. 3510 3511 Requires UBI support as well as CONFIG_LZO 3512 3513 CONFIG_UBIFS_SILENCE_MSG 3514 3515 Make the verbose messages from UBIFS stop printing. This leaves 3516 warnings and errors enabled. 3517 3518- SPL framework 3519 CONFIG_SPL 3520 Enable building of SPL globally. 3521 3522 CONFIG_SPL_LDSCRIPT 3523 LDSCRIPT for linking the SPL binary. 3524 3525 CONFIG_SPL_MAX_FOOTPRINT 3526 Maximum size in memory allocated to the SPL, BSS included. 3527 When defined, the linker checks that the actual memory 3528 used by SPL from _start to __bss_end does not exceed it. 3529 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3530 must not be both defined at the same time. 3531 3532 CONFIG_SPL_MAX_SIZE 3533 Maximum size of the SPL image (text, data, rodata, and 3534 linker lists sections), BSS excluded. 3535 When defined, the linker checks that the actual size does 3536 not exceed it. 3537 3538 CONFIG_SPL_TEXT_BASE 3539 TEXT_BASE for linking the SPL binary. 3540 3541 CONFIG_SPL_RELOC_TEXT_BASE 3542 Address to relocate to. If unspecified, this is equal to 3543 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3544 3545 CONFIG_SPL_BSS_START_ADDR 3546 Link address for the BSS within the SPL binary. 3547 3548 CONFIG_SPL_BSS_MAX_SIZE 3549 Maximum size in memory allocated to the SPL BSS. 3550 When defined, the linker checks that the actual memory used 3551 by SPL from __bss_start to __bss_end does not exceed it. 3552 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3553 must not be both defined at the same time. 3554 3555 CONFIG_SPL_STACK 3556 Adress of the start of the stack SPL will use 3557 3558 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3559 When defined, SPL will panic() if the image it has 3560 loaded does not have a signature. 3561 Defining this is useful when code which loads images 3562 in SPL cannot guarantee that absolutely all read errors 3563 will be caught. 3564 An example is the LPC32XX MLC NAND driver, which will 3565 consider that a completely unreadable NAND block is bad, 3566 and thus should be skipped silently. 3567 3568 CONFIG_SPL_RELOC_STACK 3569 Adress of the start of the stack SPL will use after 3570 relocation. If unspecified, this is equal to 3571 CONFIG_SPL_STACK. 3572 3573 CONFIG_SYS_SPL_MALLOC_START 3574 Starting address of the malloc pool used in SPL. 3575 3576 CONFIG_SYS_SPL_MALLOC_SIZE 3577 The size of the malloc pool used in SPL. 3578 3579 CONFIG_SPL_FRAMEWORK 3580 Enable the SPL framework under common/. This framework 3581 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3582 NAND loading of the Linux Kernel. 3583 3584 CONFIG_SPL_OS_BOOT 3585 Enable booting directly to an OS from SPL. 3586 See also: doc/README.falcon 3587 3588 CONFIG_SPL_DISPLAY_PRINT 3589 For ARM, enable an optional function to print more information 3590 about the running system. 3591 3592 CONFIG_SPL_INIT_MINIMAL 3593 Arch init code should be built for a very small image 3594 3595 CONFIG_SPL_LIBCOMMON_SUPPORT 3596 Support for common/libcommon.o in SPL binary 3597 3598 CONFIG_SPL_LIBDISK_SUPPORT 3599 Support for disk/libdisk.o in SPL binary 3600 3601 CONFIG_SPL_I2C_SUPPORT 3602 Support for drivers/i2c/libi2c.o in SPL binary 3603 3604 CONFIG_SPL_GPIO_SUPPORT 3605 Support for drivers/gpio/libgpio.o in SPL binary 3606 3607 CONFIG_SPL_MMC_SUPPORT 3608 Support for drivers/mmc/libmmc.o in SPL binary 3609 3610 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3611 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3612 Address and partition on the MMC to load U-Boot from 3613 when the MMC is being used in raw mode. 3614 3615 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3616 Partition on the MMC to load U-Boot from when the MMC is being 3617 used in raw mode 3618 3619 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3620 Sector to load kernel uImage from when MMC is being 3621 used in raw mode (for Falcon mode) 3622 3623 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3624 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3625 Sector and number of sectors to load kernel argument 3626 parameters from when MMC is being used in raw mode 3627 (for falcon mode) 3628 3629 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3630 Partition on the MMC to load U-Boot from when the MMC is being 3631 used in fs mode 3632 3633 CONFIG_SPL_FAT_SUPPORT 3634 Support for fs/fat/libfat.o in SPL binary 3635 3636 CONFIG_SPL_EXT_SUPPORT 3637 Support for EXT filesystem in SPL binary 3638 3639 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3640 Filename to read to load U-Boot when reading from filesystem 3641 3642 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3643 Filename to read to load kernel uImage when reading 3644 from filesystem (for Falcon mode) 3645 3646 CONFIG_SPL_FS_LOAD_ARGS_NAME 3647 Filename to read to load kernel argument parameters 3648 when reading from filesystem (for Falcon mode) 3649 3650 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3651 Set this for NAND SPL on PPC mpc83xx targets, so that 3652 start.S waits for the rest of the SPL to load before 3653 continuing (the hardware starts execution after just 3654 loading the first page rather than the full 4K). 3655 3656 CONFIG_SPL_SKIP_RELOCATE 3657 Avoid SPL relocation 3658 3659 CONFIG_SPL_NAND_BASE 3660 Include nand_base.c in the SPL. Requires 3661 CONFIG_SPL_NAND_DRIVERS. 3662 3663 CONFIG_SPL_NAND_DRIVERS 3664 SPL uses normal NAND drivers, not minimal drivers. 3665 3666 CONFIG_SPL_NAND_ECC 3667 Include standard software ECC in the SPL 3668 3669 CONFIG_SPL_NAND_SIMPLE 3670 Support for NAND boot using simple NAND drivers that 3671 expose the cmd_ctrl() interface. 3672 3673 CONFIG_SPL_MTD_SUPPORT 3674 Support for the MTD subsystem within SPL. Useful for 3675 environment on NAND support within SPL. 3676 3677 CONFIG_SPL_NAND_RAW_ONLY 3678 Support to boot only raw u-boot.bin images. Use this only 3679 if you need to save space. 3680 3681 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3682 Set for the SPL on PPC mpc8xxx targets, support for 3683 drivers/ddr/fsl/libddr.o in SPL binary. 3684 3685 CONFIG_SPL_COMMON_INIT_DDR 3686 Set for common ddr init with serial presence detect in 3687 SPL binary. 3688 3689 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3690 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3691 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3692 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3693 CONFIG_SYS_NAND_ECCBYTES 3694 Defines the size and behavior of the NAND that SPL uses 3695 to read U-Boot 3696 3697 CONFIG_SPL_NAND_BOOT 3698 Add support NAND boot 3699 3700 CONFIG_SYS_NAND_U_BOOT_OFFS 3701 Location in NAND to read U-Boot from 3702 3703 CONFIG_SYS_NAND_U_BOOT_DST 3704 Location in memory to load U-Boot to 3705 3706 CONFIG_SYS_NAND_U_BOOT_SIZE 3707 Size of image to load 3708 3709 CONFIG_SYS_NAND_U_BOOT_START 3710 Entry point in loaded image to jump to 3711 3712 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3713 Define this if you need to first read the OOB and then the 3714 data. This is used, for example, on davinci platforms. 3715 3716 CONFIG_SPL_OMAP3_ID_NAND 3717 Support for an OMAP3-specific set of functions to return the 3718 ID and MFR of the first attached NAND chip, if present. 3719 3720 CONFIG_SPL_SERIAL_SUPPORT 3721 Support for drivers/serial/libserial.o in SPL binary 3722 3723 CONFIG_SPL_SPI_FLASH_SUPPORT 3724 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3725 3726 CONFIG_SPL_SPI_SUPPORT 3727 Support for drivers/spi/libspi.o in SPL binary 3728 3729 CONFIG_SPL_RAM_DEVICE 3730 Support for running image already present in ram, in SPL binary 3731 3732 CONFIG_SPL_LIBGENERIC_SUPPORT 3733 Support for lib/libgeneric.o in SPL binary 3734 3735 CONFIG_SPL_ENV_SUPPORT 3736 Support for the environment operating in SPL binary 3737 3738 CONFIG_SPL_NET_SUPPORT 3739 Support for the net/libnet.o in SPL binary. 3740 It conflicts with SPL env from storage medium specified by 3741 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3742 3743 CONFIG_SPL_PAD_TO 3744 Image offset to which the SPL should be padded before appending 3745 the SPL payload. By default, this is defined as 3746 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3747 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3748 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3749 3750 CONFIG_SPL_TARGET 3751 Final target image containing SPL and payload. Some SPLs 3752 use an arch-specific makefile fragment instead, for 3753 example if more than one image needs to be produced. 3754 3755 CONFIG_FIT_SPL_PRINT 3756 Printing information about a FIT image adds quite a bit of 3757 code to SPL. So this is normally disabled in SPL. Use this 3758 option to re-enable it. This will affect the output of the 3759 bootm command when booting a FIT image. 3760 3761- TPL framework 3762 CONFIG_TPL 3763 Enable building of TPL globally. 3764 3765 CONFIG_TPL_PAD_TO 3766 Image offset to which the TPL should be padded before appending 3767 the TPL payload. By default, this is defined as 3768 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3769 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3770 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3771 3772Modem Support: 3773-------------- 3774 3775[so far only for SMDK2400 boards] 3776 3777- Modem support enable: 3778 CONFIG_MODEM_SUPPORT 3779 3780- RTS/CTS Flow control enable: 3781 CONFIG_HWFLOW 3782 3783- Modem debug support: 3784 CONFIG_MODEM_SUPPORT_DEBUG 3785 3786 Enables debugging stuff (char screen[1024], dbg()) 3787 for modem support. Useful only with BDI2000. 3788 3789- Interrupt support (PPC): 3790 3791 There are common interrupt_init() and timer_interrupt() 3792 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3793 for CPU specific initialization. interrupt_init_cpu() 3794 should set decrementer_count to appropriate value. If 3795 CPU resets decrementer automatically after interrupt 3796 (ppc4xx) it should set decrementer_count to zero. 3797 timer_interrupt() calls timer_interrupt_cpu() for CPU 3798 specific handling. If board has watchdog / status_led 3799 / other_activity_monitor it works automatically from 3800 general timer_interrupt(). 3801 3802- General: 3803 3804 In the target system modem support is enabled when a 3805 specific key (key combination) is pressed during 3806 power-on. Otherwise U-Boot will boot normally 3807 (autoboot). The key_pressed() function is called from 3808 board_init(). Currently key_pressed() is a dummy 3809 function, returning 1 and thus enabling modem 3810 initialization. 3811 3812 If there are no modem init strings in the 3813 environment, U-Boot proceed to autoboot; the 3814 previous output (banner, info printfs) will be 3815 suppressed, though. 3816 3817 See also: doc/README.Modem 3818 3819Board initialization settings: 3820------------------------------ 3821 3822During Initialization u-boot calls a number of board specific functions 3823to allow the preparation of board specific prerequisites, e.g. pin setup 3824before drivers are initialized. To enable these callbacks the 3825following configuration macros have to be defined. Currently this is 3826architecture specific, so please check arch/your_architecture/lib/board.c 3827typically in board_init_f() and board_init_r(). 3828 3829- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3830- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3831- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3832- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3833 3834Configuration Settings: 3835----------------------- 3836 3837- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3838 Optionally it can be defined to support 64-bit memory commands. 3839 3840- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3841 undefine this when you're short of memory. 3842 3843- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3844 width of the commands listed in the 'help' command output. 3845 3846- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3847 prompt for user input. 3848 3849- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3850 3851- CONFIG_SYS_PBSIZE: Buffer size for Console output 3852 3853- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3854 3855- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3856 the application (usually a Linux kernel) when it is 3857 booted 3858 3859- CONFIG_SYS_BAUDRATE_TABLE: 3860 List of legal baudrate settings for this board. 3861 3862- CONFIG_SYS_CONSOLE_INFO_QUIET 3863 Suppress display of console information at boot. 3864 3865- CONFIG_SYS_CONSOLE_IS_IN_ENV 3866 If the board specific function 3867 extern int overwrite_console (void); 3868 returns 1, the stdin, stderr and stdout are switched to the 3869 serial port, else the settings in the environment are used. 3870 3871- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3872 Enable the call to overwrite_console(). 3873 3874- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3875 Enable overwrite of previous console environment settings. 3876 3877- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3878 Begin and End addresses of the area used by the 3879 simple memory test. 3880 3881- CONFIG_SYS_ALT_MEMTEST: 3882 Enable an alternate, more extensive memory test. 3883 3884- CONFIG_SYS_MEMTEST_SCRATCH: 3885 Scratch address used by the alternate memory test 3886 You only need to set this if address zero isn't writeable 3887 3888- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3889 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3890 this specified memory area will get subtracted from the top 3891 (end) of RAM and won't get "touched" at all by U-Boot. By 3892 fixing up gd->ram_size the Linux kernel should gets passed 3893 the now "corrected" memory size and won't touch it either. 3894 This should work for arch/ppc and arch/powerpc. Only Linux 3895 board ports in arch/powerpc with bootwrapper support that 3896 recalculate the memory size from the SDRAM controller setup 3897 will have to get fixed in Linux additionally. 3898 3899 This option can be used as a workaround for the 440EPx/GRx 3900 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3901 be touched. 3902 3903 WARNING: Please make sure that this value is a multiple of 3904 the Linux page size (normally 4k). If this is not the case, 3905 then the end address of the Linux memory will be located at a 3906 non page size aligned address and this could cause major 3907 problems. 3908 3909- CONFIG_SYS_LOADS_BAUD_CHANGE: 3910 Enable temporary baudrate change while serial download 3911 3912- CONFIG_SYS_SDRAM_BASE: 3913 Physical start address of SDRAM. _Must_ be 0 here. 3914 3915- CONFIG_SYS_MBIO_BASE: 3916 Physical start address of Motherboard I/O (if using a 3917 Cogent motherboard) 3918 3919- CONFIG_SYS_FLASH_BASE: 3920 Physical start address of Flash memory. 3921 3922- CONFIG_SYS_MONITOR_BASE: 3923 Physical start address of boot monitor code (set by 3924 make config files to be same as the text base address 3925 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3926 CONFIG_SYS_FLASH_BASE when booting from flash. 3927 3928- CONFIG_SYS_MONITOR_LEN: 3929 Size of memory reserved for monitor code, used to 3930 determine _at_compile_time_ (!) if the environment is 3931 embedded within the U-Boot image, or in a separate 3932 flash sector. 3933 3934- CONFIG_SYS_MALLOC_LEN: 3935 Size of DRAM reserved for malloc() use. 3936 3937- CONFIG_SYS_MALLOC_F_LEN 3938 Size of the malloc() pool for use before relocation. If 3939 this is defined, then a very simple malloc() implementation 3940 will become available before relocation. The address is just 3941 below the global data, and the stack is moved down to make 3942 space. 3943 3944 This feature allocates regions with increasing addresses 3945 within the region. calloc() is supported, but realloc() 3946 is not available. free() is supported but does nothing. 3947 The memory will be freed (or in fact just forgotten) when 3948 U-Boot relocates itself. 3949 3950 Pre-relocation malloc() is only supported on ARM and sandbox 3951 at present but is fairly easy to enable for other archs. 3952 3953- CONFIG_SYS_MALLOC_SIMPLE 3954 Provides a simple and small malloc() and calloc() for those 3955 boards which do not use the full malloc in SPL (which is 3956 enabled with CONFIG_SYS_SPL_MALLOC_START). 3957 3958- CONFIG_SYS_NONCACHED_MEMORY: 3959 Size of non-cached memory area. This area of memory will be 3960 typically located right below the malloc() area and mapped 3961 uncached in the MMU. This is useful for drivers that would 3962 otherwise require a lot of explicit cache maintenance. For 3963 some drivers it's also impossible to properly maintain the 3964 cache. For example if the regions that need to be flushed 3965 are not a multiple of the cache-line size, *and* padding 3966 cannot be allocated between the regions to align them (i.e. 3967 if the HW requires a contiguous array of regions, and the 3968 size of each region is not cache-aligned), then a flush of 3969 one region may result in overwriting data that hardware has 3970 written to another region in the same cache-line. This can 3971 happen for example in network drivers where descriptors for 3972 buffers are typically smaller than the CPU cache-line (e.g. 3973 16 bytes vs. 32 or 64 bytes). 3974 3975 Non-cached memory is only supported on 32-bit ARM at present. 3976 3977- CONFIG_SYS_BOOTM_LEN: 3978 Normally compressed uImages are limited to an 3979 uncompressed size of 8 MBytes. If this is not enough, 3980 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3981 to adjust this setting to your needs. 3982 3983- CONFIG_SYS_BOOTMAPSZ: 3984 Maximum size of memory mapped by the startup code of 3985 the Linux kernel; all data that must be processed by 3986 the Linux kernel (bd_info, boot arguments, FDT blob if 3987 used) must be put below this limit, unless "bootm_low" 3988 environment variable is defined and non-zero. In such case 3989 all data for the Linux kernel must be between "bootm_low" 3990 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3991 variable "bootm_mapsize" will override the value of 3992 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3993 then the value in "bootm_size" will be used instead. 3994 3995- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3996 Enable initrd_high functionality. If defined then the 3997 initrd_high feature is enabled and the bootm ramdisk subcommand 3998 is enabled. 3999 4000- CONFIG_SYS_BOOT_GET_CMDLINE: 4001 Enables allocating and saving kernel cmdline in space between 4002 "bootm_low" and "bootm_low" + BOOTMAPSZ. 4003 4004- CONFIG_SYS_BOOT_GET_KBD: 4005 Enables allocating and saving a kernel copy of the bd_info in 4006 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 4007 4008- CONFIG_SYS_MAX_FLASH_BANKS: 4009 Max number of Flash memory banks 4010 4011- CONFIG_SYS_MAX_FLASH_SECT: 4012 Max number of sectors on a Flash chip 4013 4014- CONFIG_SYS_FLASH_ERASE_TOUT: 4015 Timeout for Flash erase operations (in ms) 4016 4017- CONFIG_SYS_FLASH_WRITE_TOUT: 4018 Timeout for Flash write operations (in ms) 4019 4020- CONFIG_SYS_FLASH_LOCK_TOUT 4021 Timeout for Flash set sector lock bit operation (in ms) 4022 4023- CONFIG_SYS_FLASH_UNLOCK_TOUT 4024 Timeout for Flash clear lock bits operation (in ms) 4025 4026- CONFIG_SYS_FLASH_PROTECTION 4027 If defined, hardware flash sectors protection is used 4028 instead of U-Boot software protection. 4029 4030- CONFIG_SYS_DIRECT_FLASH_TFTP: 4031 4032 Enable TFTP transfers directly to flash memory; 4033 without this option such a download has to be 4034 performed in two steps: (1) download to RAM, and (2) 4035 copy from RAM to flash. 4036 4037 The two-step approach is usually more reliable, since 4038 you can check if the download worked before you erase 4039 the flash, but in some situations (when system RAM is 4040 too limited to allow for a temporary copy of the 4041 downloaded image) this option may be very useful. 4042 4043- CONFIG_SYS_FLASH_CFI: 4044 Define if the flash driver uses extra elements in the 4045 common flash structure for storing flash geometry. 4046 4047- CONFIG_FLASH_CFI_DRIVER 4048 This option also enables the building of the cfi_flash driver 4049 in the drivers directory 4050 4051- CONFIG_FLASH_CFI_MTD 4052 This option enables the building of the cfi_mtd driver 4053 in the drivers directory. The driver exports CFI flash 4054 to the MTD layer. 4055 4056- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 4057 Use buffered writes to flash. 4058 4059- CONFIG_FLASH_SPANSION_S29WS_N 4060 s29ws-n MirrorBit flash has non-standard addresses for buffered 4061 write commands. 4062 4063- CONFIG_SYS_FLASH_QUIET_TEST 4064 If this option is defined, the common CFI flash doesn't 4065 print it's warning upon not recognized FLASH banks. This 4066 is useful, if some of the configured banks are only 4067 optionally available. 4068 4069- CONFIG_FLASH_SHOW_PROGRESS 4070 If defined (must be an integer), print out countdown 4071 digits and dots. Recommended value: 45 (9..1) for 80 4072 column displays, 15 (3..1) for 40 column displays. 4073 4074- CONFIG_FLASH_VERIFY 4075 If defined, the content of the flash (destination) is compared 4076 against the source after the write operation. An error message 4077 will be printed when the contents are not identical. 4078 Please note that this option is useless in nearly all cases, 4079 since such flash programming errors usually are detected earlier 4080 while unprotecting/erasing/programming. Please only enable 4081 this option if you really know what you are doing. 4082 4083- CONFIG_SYS_RX_ETH_BUFFER: 4084 Defines the number of Ethernet receive buffers. On some 4085 Ethernet controllers it is recommended to set this value 4086 to 8 or even higher (EEPRO100 or 405 EMAC), since all 4087 buffers can be full shortly after enabling the interface 4088 on high Ethernet traffic. 4089 Defaults to 4 if not defined. 4090 4091- CONFIG_ENV_MAX_ENTRIES 4092 4093 Maximum number of entries in the hash table that is used 4094 internally to store the environment settings. The default 4095 setting is supposed to be generous and should work in most 4096 cases. This setting can be used to tune behaviour; see 4097 lib/hashtable.c for details. 4098 4099- CONFIG_ENV_FLAGS_LIST_DEFAULT 4100- CONFIG_ENV_FLAGS_LIST_STATIC 4101 Enable validation of the values given to environment variables when 4102 calling env set. Variables can be restricted to only decimal, 4103 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 4104 the variables can also be restricted to IP address or MAC address. 4105 4106 The format of the list is: 4107 type_attribute = [s|d|x|b|i|m] 4108 access_attribute = [a|r|o|c] 4109 attributes = type_attribute[access_attribute] 4110 entry = variable_name[:attributes] 4111 list = entry[,list] 4112 4113 The type attributes are: 4114 s - String (default) 4115 d - Decimal 4116 x - Hexadecimal 4117 b - Boolean ([1yYtT|0nNfF]) 4118 i - IP address 4119 m - MAC address 4120 4121 The access attributes are: 4122 a - Any (default) 4123 r - Read-only 4124 o - Write-once 4125 c - Change-default 4126 4127 - CONFIG_ENV_FLAGS_LIST_DEFAULT 4128 Define this to a list (string) to define the ".flags" 4129 environment variable in the default or embedded environment. 4130 4131 - CONFIG_ENV_FLAGS_LIST_STATIC 4132 Define this to a list (string) to define validation that 4133 should be done if an entry is not found in the ".flags" 4134 environment variable. To override a setting in the static 4135 list, simply add an entry for the same variable name to the 4136 ".flags" variable. 4137 4138 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 4139 regular expression. This allows multiple variables to define the same 4140 flags without explicitly listing them for each variable. 4141 4142- CONFIG_ENV_ACCESS_IGNORE_FORCE 4143 If defined, don't allow the -f switch to env set override variable 4144 access flags. 4145 4146- CONFIG_SYS_GENERIC_BOARD 4147 This selects the architecture-generic board system instead of the 4148 architecture-specific board files. It is intended to move boards 4149 to this new framework over time. Defining this will disable the 4150 arch/foo/lib/board.c file and use common/board_f.c and 4151 common/board_r.c instead. To use this option your architecture 4152 must support it (i.e. must select HAVE_GENERIC_BOARD in arch/Kconfig). 4153 If you find problems enabling this option on your board please report 4154 the problem and send patches! 4155 4156- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 4157 This is set by OMAP boards for the max time that reset should 4158 be asserted. See doc/README.omap-reset-time for details on how 4159 the value can be calculated on a given board. 4160 4161- CONFIG_USE_STDINT 4162 If stdint.h is available with your toolchain you can define this 4163 option to enable it. You can provide option 'USE_STDINT=1' when 4164 building U-Boot to enable this. 4165 4166The following definitions that deal with the placement and management 4167of environment data (variable area); in general, we support the 4168following configurations: 4169 4170- CONFIG_BUILD_ENVCRC: 4171 4172 Builds up envcrc with the target environment so that external utils 4173 may easily extract it and embed it in final U-Boot images. 4174 4175- CONFIG_ENV_IS_IN_FLASH: 4176 4177 Define this if the environment is in flash memory. 4178 4179 a) The environment occupies one whole flash sector, which is 4180 "embedded" in the text segment with the U-Boot code. This 4181 happens usually with "bottom boot sector" or "top boot 4182 sector" type flash chips, which have several smaller 4183 sectors at the start or the end. For instance, such a 4184 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 4185 such a case you would place the environment in one of the 4186 4 kB sectors - with U-Boot code before and after it. With 4187 "top boot sector" type flash chips, you would put the 4188 environment in one of the last sectors, leaving a gap 4189 between U-Boot and the environment. 4190 4191 - CONFIG_ENV_OFFSET: 4192 4193 Offset of environment data (variable area) to the 4194 beginning of flash memory; for instance, with bottom boot 4195 type flash chips the second sector can be used: the offset 4196 for this sector is given here. 4197 4198 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 4199 4200 - CONFIG_ENV_ADDR: 4201 4202 This is just another way to specify the start address of 4203 the flash sector containing the environment (instead of 4204 CONFIG_ENV_OFFSET). 4205 4206 - CONFIG_ENV_SECT_SIZE: 4207 4208 Size of the sector containing the environment. 4209 4210 4211 b) Sometimes flash chips have few, equal sized, BIG sectors. 4212 In such a case you don't want to spend a whole sector for 4213 the environment. 4214 4215 - CONFIG_ENV_SIZE: 4216 4217 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 4218 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 4219 of this flash sector for the environment. This saves 4220 memory for the RAM copy of the environment. 4221 4222 It may also save flash memory if you decide to use this 4223 when your environment is "embedded" within U-Boot code, 4224 since then the remainder of the flash sector could be used 4225 for U-Boot code. It should be pointed out that this is 4226 STRONGLY DISCOURAGED from a robustness point of view: 4227 updating the environment in flash makes it always 4228 necessary to erase the WHOLE sector. If something goes 4229 wrong before the contents has been restored from a copy in 4230 RAM, your target system will be dead. 4231 4232 - CONFIG_ENV_ADDR_REDUND 4233 CONFIG_ENV_SIZE_REDUND 4234 4235 These settings describe a second storage area used to hold 4236 a redundant copy of the environment data, so that there is 4237 a valid backup copy in case there is a power failure during 4238 a "saveenv" operation. 4239 4240BE CAREFUL! Any changes to the flash layout, and some changes to the 4241source code will make it necessary to adapt <board>/u-boot.lds* 4242accordingly! 4243 4244 4245- CONFIG_ENV_IS_IN_NVRAM: 4246 4247 Define this if you have some non-volatile memory device 4248 (NVRAM, battery buffered SRAM) which you want to use for the 4249 environment. 4250 4251 - CONFIG_ENV_ADDR: 4252 - CONFIG_ENV_SIZE: 4253 4254 These two #defines are used to determine the memory area you 4255 want to use for environment. It is assumed that this memory 4256 can just be read and written to, without any special 4257 provision. 4258 4259BE CAREFUL! The first access to the environment happens quite early 4260in U-Boot initialization (when we try to get the setting of for the 4261console baudrate). You *MUST* have mapped your NVRAM area then, or 4262U-Boot will hang. 4263 4264Please note that even with NVRAM we still use a copy of the 4265environment in RAM: we could work on NVRAM directly, but we want to 4266keep settings there always unmodified except somebody uses "saveenv" 4267to save the current settings. 4268 4269 4270- CONFIG_ENV_IS_IN_EEPROM: 4271 4272 Use this if you have an EEPROM or similar serial access 4273 device and a driver for it. 4274 4275 - CONFIG_ENV_OFFSET: 4276 - CONFIG_ENV_SIZE: 4277 4278 These two #defines specify the offset and size of the 4279 environment area within the total memory of your EEPROM. 4280 4281 - CONFIG_SYS_I2C_EEPROM_ADDR: 4282 If defined, specified the chip address of the EEPROM device. 4283 The default address is zero. 4284 4285 - CONFIG_SYS_I2C_EEPROM_BUS: 4286 If defined, specified the i2c bus of the EEPROM device. 4287 4288 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 4289 If defined, the number of bits used to address bytes in a 4290 single page in the EEPROM device. A 64 byte page, for example 4291 would require six bits. 4292 4293 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 4294 If defined, the number of milliseconds to delay between 4295 page writes. The default is zero milliseconds. 4296 4297 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 4298 The length in bytes of the EEPROM memory array address. Note 4299 that this is NOT the chip address length! 4300 4301 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 4302 EEPROM chips that implement "address overflow" are ones 4303 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 4304 address and the extra bits end up in the "chip address" bit 4305 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 4306 byte chips. 4307 4308 Note that we consider the length of the address field to 4309 still be one byte because the extra address bits are hidden 4310 in the chip address. 4311 4312 - CONFIG_SYS_EEPROM_SIZE: 4313 The size in bytes of the EEPROM device. 4314 4315 - CONFIG_ENV_EEPROM_IS_ON_I2C 4316 define this, if you have I2C and SPI activated, and your 4317 EEPROM, which holds the environment, is on the I2C bus. 4318 4319 - CONFIG_I2C_ENV_EEPROM_BUS 4320 if you have an Environment on an EEPROM reached over 4321 I2C muxes, you can define here, how to reach this 4322 EEPROM. For example: 4323 4324 #define CONFIG_I2C_ENV_EEPROM_BUS 1 4325 4326 EEPROM which holds the environment, is reached over 4327 a pca9547 i2c mux with address 0x70, channel 3. 4328 4329- CONFIG_ENV_IS_IN_DATAFLASH: 4330 4331 Define this if you have a DataFlash memory device which you 4332 want to use for the environment. 4333 4334 - CONFIG_ENV_OFFSET: 4335 - CONFIG_ENV_ADDR: 4336 - CONFIG_ENV_SIZE: 4337 4338 These three #defines specify the offset and size of the 4339 environment area within the total memory of your DataFlash placed 4340 at the specified address. 4341 4342- CONFIG_ENV_IS_IN_SPI_FLASH: 4343 4344 Define this if you have a SPI Flash memory device which you 4345 want to use for the environment. 4346 4347 - CONFIG_ENV_OFFSET: 4348 - CONFIG_ENV_SIZE: 4349 4350 These two #defines specify the offset and size of the 4351 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 4352 aligned to an erase sector boundary. 4353 4354 - CONFIG_ENV_SECT_SIZE: 4355 4356 Define the SPI flash's sector size. 4357 4358 - CONFIG_ENV_OFFSET_REDUND (optional): 4359 4360 This setting describes a second storage area of CONFIG_ENV_SIZE 4361 size used to hold a redundant copy of the environment data, so 4362 that there is a valid backup copy in case there is a power failure 4363 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4364 aligned to an erase sector boundary. 4365 4366 - CONFIG_ENV_SPI_BUS (optional): 4367 - CONFIG_ENV_SPI_CS (optional): 4368 4369 Define the SPI bus and chip select. If not defined they will be 0. 4370 4371 - CONFIG_ENV_SPI_MAX_HZ (optional): 4372 4373 Define the SPI max work clock. If not defined then use 1MHz. 4374 4375 - CONFIG_ENV_SPI_MODE (optional): 4376 4377 Define the SPI work mode. If not defined then use SPI_MODE_3. 4378 4379- CONFIG_ENV_IS_IN_REMOTE: 4380 4381 Define this if you have a remote memory space which you 4382 want to use for the local device's environment. 4383 4384 - CONFIG_ENV_ADDR: 4385 - CONFIG_ENV_SIZE: 4386 4387 These two #defines specify the address and size of the 4388 environment area within the remote memory space. The 4389 local device can get the environment from remote memory 4390 space by SRIO or PCIE links. 4391 4392BE CAREFUL! For some special cases, the local device can not use 4393"saveenv" command. For example, the local device will get the 4394environment stored in a remote NOR flash by SRIO or PCIE link, 4395but it can not erase, write this NOR flash by SRIO or PCIE interface. 4396 4397- CONFIG_ENV_IS_IN_NAND: 4398 4399 Define this if you have a NAND device which you want to use 4400 for the environment. 4401 4402 - CONFIG_ENV_OFFSET: 4403 - CONFIG_ENV_SIZE: 4404 4405 These two #defines specify the offset and size of the environment 4406 area within the first NAND device. CONFIG_ENV_OFFSET must be 4407 aligned to an erase block boundary. 4408 4409 - CONFIG_ENV_OFFSET_REDUND (optional): 4410 4411 This setting describes a second storage area of CONFIG_ENV_SIZE 4412 size used to hold a redundant copy of the environment data, so 4413 that there is a valid backup copy in case there is a power failure 4414 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4415 aligned to an erase block boundary. 4416 4417 - CONFIG_ENV_RANGE (optional): 4418 4419 Specifies the length of the region in which the environment 4420 can be written. This should be a multiple of the NAND device's 4421 block size. Specifying a range with more erase blocks than 4422 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4423 the range to be avoided. 4424 4425 - CONFIG_ENV_OFFSET_OOB (optional): 4426 4427 Enables support for dynamically retrieving the offset of the 4428 environment from block zero's out-of-band data. The 4429 "nand env.oob" command can be used to record this offset. 4430 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4431 using CONFIG_ENV_OFFSET_OOB. 4432 4433- CONFIG_NAND_ENV_DST 4434 4435 Defines address in RAM to which the nand_spl code should copy the 4436 environment. If redundant environment is used, it will be copied to 4437 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4438 4439- CONFIG_ENV_IS_IN_UBI: 4440 4441 Define this if you have an UBI volume that you want to use for the 4442 environment. This has the benefit of wear-leveling the environment 4443 accesses, which is important on NAND. 4444 4445 - CONFIG_ENV_UBI_PART: 4446 4447 Define this to a string that is the mtd partition containing the UBI. 4448 4449 - CONFIG_ENV_UBI_VOLUME: 4450 4451 Define this to the name of the volume that you want to store the 4452 environment in. 4453 4454 - CONFIG_ENV_UBI_VOLUME_REDUND: 4455 4456 Define this to the name of another volume to store a second copy of 4457 the environment in. This will enable redundant environments in UBI. 4458 It is assumed that both volumes are in the same MTD partition. 4459 4460 - CONFIG_UBI_SILENCE_MSG 4461 - CONFIG_UBIFS_SILENCE_MSG 4462 4463 You will probably want to define these to avoid a really noisy system 4464 when storing the env in UBI. 4465 4466- CONFIG_ENV_IS_IN_FAT: 4467 Define this if you want to use the FAT file system for the environment. 4468 4469 - FAT_ENV_INTERFACE: 4470 4471 Define this to a string that is the name of the block device. 4472 4473 - FAT_ENV_DEV_AND_PART: 4474 4475 Define this to a string to specify the partition of the device. It can 4476 be as following: 4477 4478 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4479 - "D:P": device D partition P. Error occurs if device D has no 4480 partition table. 4481 - "D:0": device D. 4482 - "D" or "D:": device D partition 1 if device D has partition 4483 table, or the whole device D if has no partition 4484 table. 4485 - "D:auto": first partition in device D with bootable flag set. 4486 If none, first valid partition in device D. If no 4487 partition table then means device D. 4488 4489 - FAT_ENV_FILE: 4490 4491 It's a string of the FAT file name. This file use to store the 4492 environment. 4493 4494 - CONFIG_FAT_WRITE: 4495 This should be defined. Otherwise it cannot save the environment file. 4496 4497- CONFIG_ENV_IS_IN_MMC: 4498 4499 Define this if you have an MMC device which you want to use for the 4500 environment. 4501 4502 - CONFIG_SYS_MMC_ENV_DEV: 4503 4504 Specifies which MMC device the environment is stored in. 4505 4506 - CONFIG_SYS_MMC_ENV_PART (optional): 4507 4508 Specifies which MMC partition the environment is stored in. If not 4509 set, defaults to partition 0, the user area. Common values might be 4510 1 (first MMC boot partition), 2 (second MMC boot partition). 4511 4512 - CONFIG_ENV_OFFSET: 4513 - CONFIG_ENV_SIZE: 4514 4515 These two #defines specify the offset and size of the environment 4516 area within the specified MMC device. 4517 4518 If offset is positive (the usual case), it is treated as relative to 4519 the start of the MMC partition. If offset is negative, it is treated 4520 as relative to the end of the MMC partition. This can be useful if 4521 your board may be fitted with different MMC devices, which have 4522 different sizes for the MMC partitions, and you always want the 4523 environment placed at the very end of the partition, to leave the 4524 maximum possible space before it, to store other data. 4525 4526 These two values are in units of bytes, but must be aligned to an 4527 MMC sector boundary. 4528 4529 - CONFIG_ENV_OFFSET_REDUND (optional): 4530 4531 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4532 hold a redundant copy of the environment data. This provides a 4533 valid backup copy in case the other copy is corrupted, e.g. due 4534 to a power failure during a "saveenv" operation. 4535 4536 This value may also be positive or negative; this is handled in the 4537 same way as CONFIG_ENV_OFFSET. 4538 4539 This value is also in units of bytes, but must also be aligned to 4540 an MMC sector boundary. 4541 4542 - CONFIG_ENV_SIZE_REDUND (optional): 4543 4544 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4545 set. If this value is set, it must be set to the same value as 4546 CONFIG_ENV_SIZE. 4547 4548- CONFIG_SYS_SPI_INIT_OFFSET 4549 4550 Defines offset to the initial SPI buffer area in DPRAM. The 4551 area is used at an early stage (ROM part) if the environment 4552 is configured to reside in the SPI EEPROM: We need a 520 byte 4553 scratch DPRAM area. It is used between the two initialization 4554 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4555 to be a good choice since it makes it far enough from the 4556 start of the data area as well as from the stack pointer. 4557 4558Please note that the environment is read-only until the monitor 4559has been relocated to RAM and a RAM copy of the environment has been 4560created; also, when using EEPROM you will have to use getenv_f() 4561until then to read environment variables. 4562 4563The environment is protected by a CRC32 checksum. Before the monitor 4564is relocated into RAM, as a result of a bad CRC you will be working 4565with the compiled-in default environment - *silently*!!! [This is 4566necessary, because the first environment variable we need is the 4567"baudrate" setting for the console - if we have a bad CRC, we don't 4568have any device yet where we could complain.] 4569 4570Note: once the monitor has been relocated, then it will complain if 4571the default environment is used; a new CRC is computed as soon as you 4572use the "saveenv" command to store a valid environment. 4573 4574- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4575 Echo the inverted Ethernet link state to the fault LED. 4576 4577 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4578 also needs to be defined. 4579 4580- CONFIG_SYS_FAULT_MII_ADDR: 4581 MII address of the PHY to check for the Ethernet link state. 4582 4583- CONFIG_NS16550_MIN_FUNCTIONS: 4584 Define this if you desire to only have use of the NS16550_init 4585 and NS16550_putc functions for the serial driver located at 4586 drivers/serial/ns16550.c. This option is useful for saving 4587 space for already greatly restricted images, including but not 4588 limited to NAND_SPL configurations. 4589 4590- CONFIG_DISPLAY_BOARDINFO 4591 Display information about the board that U-Boot is running on 4592 when U-Boot starts up. The board function checkboard() is called 4593 to do this. 4594 4595- CONFIG_DISPLAY_BOARDINFO_LATE 4596 Similar to the previous option, but display this information 4597 later, once stdio is running and output goes to the LCD, if 4598 present. 4599 4600- CONFIG_BOARD_SIZE_LIMIT: 4601 Maximum size of the U-Boot image. When defined, the 4602 build system checks that the actual size does not 4603 exceed it. 4604 4605Low Level (hardware related) configuration options: 4606--------------------------------------------------- 4607 4608- CONFIG_SYS_CACHELINE_SIZE: 4609 Cache Line Size of the CPU. 4610 4611- CONFIG_SYS_DEFAULT_IMMR: 4612 Default address of the IMMR after system reset. 4613 4614 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4615 and RPXsuper) to be able to adjust the position of 4616 the IMMR register after a reset. 4617 4618- CONFIG_SYS_CCSRBAR_DEFAULT: 4619 Default (power-on reset) physical address of CCSR on Freescale 4620 PowerPC SOCs. 4621 4622- CONFIG_SYS_CCSRBAR: 4623 Virtual address of CCSR. On a 32-bit build, this is typically 4624 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4625 4626 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4627 for cross-platform code that uses that macro instead. 4628 4629- CONFIG_SYS_CCSRBAR_PHYS: 4630 Physical address of CCSR. CCSR can be relocated to a new 4631 physical address, if desired. In this case, this macro should 4632 be set to that address. Otherwise, it should be set to the 4633 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4634 is typically relocated on 36-bit builds. It is recommended 4635 that this macro be defined via the _HIGH and _LOW macros: 4636 4637 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4638 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4639 4640- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4641 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4642 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4643 used in assembly code, so it must not contain typecasts or 4644 integer size suffixes (e.g. "ULL"). 4645 4646- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4647 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4648 used in assembly code, so it must not contain typecasts or 4649 integer size suffixes (e.g. "ULL"). 4650 4651- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4652 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4653 forced to a value that ensures that CCSR is not relocated. 4654 4655- Floppy Disk Support: 4656 CONFIG_SYS_FDC_DRIVE_NUMBER 4657 4658 the default drive number (default value 0) 4659 4660 CONFIG_SYS_ISA_IO_STRIDE 4661 4662 defines the spacing between FDC chipset registers 4663 (default value 1) 4664 4665 CONFIG_SYS_ISA_IO_OFFSET 4666 4667 defines the offset of register from address. It 4668 depends on which part of the data bus is connected to 4669 the FDC chipset. (default value 0) 4670 4671 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4672 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4673 default value. 4674 4675 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4676 fdc_hw_init() is called at the beginning of the FDC 4677 setup. fdc_hw_init() must be provided by the board 4678 source code. It is used to make hardware-dependent 4679 initializations. 4680 4681- CONFIG_IDE_AHB: 4682 Most IDE controllers were designed to be connected with PCI 4683 interface. Only few of them were designed for AHB interface. 4684 When software is doing ATA command and data transfer to 4685 IDE devices through IDE-AHB controller, some additional 4686 registers accessing to these kind of IDE-AHB controller 4687 is required. 4688 4689- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4690 DO NOT CHANGE unless you know exactly what you're 4691 doing! (11-4) [MPC8xx/82xx systems only] 4692 4693- CONFIG_SYS_INIT_RAM_ADDR: 4694 4695 Start address of memory area that can be used for 4696 initial data and stack; please note that this must be 4697 writable memory that is working WITHOUT special 4698 initialization, i. e. you CANNOT use normal RAM which 4699 will become available only after programming the 4700 memory controller and running certain initialization 4701 sequences. 4702 4703 U-Boot uses the following memory types: 4704 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4705 - MPC824X: data cache 4706 - PPC4xx: data cache 4707 4708- CONFIG_SYS_GBL_DATA_OFFSET: 4709 4710 Offset of the initial data structure in the memory 4711 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4712 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4713 data is located at the end of the available space 4714 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4715 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4716 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4717 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4718 4719 Note: 4720 On the MPC824X (or other systems that use the data 4721 cache for initial memory) the address chosen for 4722 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4723 point to an otherwise UNUSED address space between 4724 the top of RAM and the start of the PCI space. 4725 4726- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4727 4728- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4729 4730- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4731 4732- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4733 4734- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4735 4736- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4737 4738- CONFIG_SYS_OR_TIMING_SDRAM: 4739 SDRAM timing 4740 4741- CONFIG_SYS_MAMR_PTA: 4742 periodic timer for refresh 4743 4744- CONFIG_SYS_DER: Debug Event Register (37-47) 4745 4746- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4747 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4748 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4749 CONFIG_SYS_BR1_PRELIM: 4750 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4751 4752- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4753 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4754 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4755 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4756 4757- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4758 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4759 Machine Mode Register and Memory Periodic Timer 4760 Prescaler definitions (SDRAM timing) 4761 4762- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4763 enable I2C microcode relocation patch (MPC8xx); 4764 define relocation offset in DPRAM [DSP2] 4765 4766- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4767 enable SMC microcode relocation patch (MPC8xx); 4768 define relocation offset in DPRAM [SMC1] 4769 4770- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4771 enable SPI microcode relocation patch (MPC8xx); 4772 define relocation offset in DPRAM [SCC4] 4773 4774- CONFIG_SYS_USE_OSCCLK: 4775 Use OSCM clock mode on MBX8xx board. Be careful, 4776 wrong setting might damage your board. Read 4777 doc/README.MBX before setting this variable! 4778 4779- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4780 Offset of the bootmode word in DPRAM used by post 4781 (Power On Self Tests). This definition overrides 4782 #define'd default value in commproc.h resp. 4783 cpm_8260.h. 4784 4785- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4786 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4787 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4788 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4789 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4790 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4791 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4792 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4793 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4794 4795- CONFIG_PCI_DISABLE_PCIE: 4796 Disable PCI-Express on systems where it is supported but not 4797 required. 4798 4799- CONFIG_PCI_ENUM_ONLY 4800 Only scan through and get the devices on the buses. 4801 Don't do any setup work, presumably because someone or 4802 something has already done it, and we don't need to do it 4803 a second time. Useful for platforms that are pre-booted 4804 by coreboot or similar. 4805 4806- CONFIG_PCI_INDIRECT_BRIDGE: 4807 Enable support for indirect PCI bridges. 4808 4809- CONFIG_SYS_SRIO: 4810 Chip has SRIO or not 4811 4812- CONFIG_SRIO1: 4813 Board has SRIO 1 port available 4814 4815- CONFIG_SRIO2: 4816 Board has SRIO 2 port available 4817 4818- CONFIG_SRIO_PCIE_BOOT_MASTER 4819 Board can support master function for Boot from SRIO and PCIE 4820 4821- CONFIG_SYS_SRIOn_MEM_VIRT: 4822 Virtual Address of SRIO port 'n' memory region 4823 4824- CONFIG_SYS_SRIOn_MEM_PHYS: 4825 Physical Address of SRIO port 'n' memory region 4826 4827- CONFIG_SYS_SRIOn_MEM_SIZE: 4828 Size of SRIO port 'n' memory region 4829 4830- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4831 Defined to tell the NAND controller that the NAND chip is using 4832 a 16 bit bus. 4833 Not all NAND drivers use this symbol. 4834 Example of drivers that use it: 4835 - drivers/mtd/nand/ndfc.c 4836 - drivers/mtd/nand/mxc_nand.c 4837 4838- CONFIG_SYS_NDFC_EBC0_CFG 4839 Sets the EBC0_CFG register for the NDFC. If not defined 4840 a default value will be used. 4841 4842- CONFIG_SPD_EEPROM 4843 Get DDR timing information from an I2C EEPROM. Common 4844 with pluggable memory modules such as SODIMMs 4845 4846 SPD_EEPROM_ADDRESS 4847 I2C address of the SPD EEPROM 4848 4849- CONFIG_SYS_SPD_BUS_NUM 4850 If SPD EEPROM is on an I2C bus other than the first 4851 one, specify here. Note that the value must resolve 4852 to something your driver can deal with. 4853 4854- CONFIG_SYS_DDR_RAW_TIMING 4855 Get DDR timing information from other than SPD. Common with 4856 soldered DDR chips onboard without SPD. DDR raw timing 4857 parameters are extracted from datasheet and hard-coded into 4858 header files or board specific files. 4859 4860- CONFIG_FSL_DDR_INTERACTIVE 4861 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4862 4863- CONFIG_FSL_DDR_SYNC_REFRESH 4864 Enable sync of refresh for multiple controllers. 4865 4866- CONFIG_FSL_DDR_BIST 4867 Enable built-in memory test for Freescale DDR controllers. 4868 4869- CONFIG_SYS_83XX_DDR_USES_CS0 4870 Only for 83xx systems. If specified, then DDR should 4871 be configured using CS0 and CS1 instead of CS2 and CS3. 4872 4873- CONFIG_ETHER_ON_FEC[12] 4874 Define to enable FEC[12] on a 8xx series processor. 4875 4876- CONFIG_FEC[12]_PHY 4877 Define to the hardcoded PHY address which corresponds 4878 to the given FEC; i. e. 4879 #define CONFIG_FEC1_PHY 4 4880 means that the PHY with address 4 is connected to FEC1 4881 4882 When set to -1, means to probe for first available. 4883 4884- CONFIG_FEC[12]_PHY_NORXERR 4885 The PHY does not have a RXERR line (RMII only). 4886 (so program the FEC to ignore it). 4887 4888- CONFIG_RMII 4889 Enable RMII mode for all FECs. 4890 Note that this is a global option, we can't 4891 have one FEC in standard MII mode and another in RMII mode. 4892 4893- CONFIG_CRC32_VERIFY 4894 Add a verify option to the crc32 command. 4895 The syntax is: 4896 4897 => crc32 -v <address> <count> <crc32> 4898 4899 Where address/count indicate a memory area 4900 and crc32 is the correct crc32 which the 4901 area should have. 4902 4903- CONFIG_LOOPW 4904 Add the "loopw" memory command. This only takes effect if 4905 the memory commands are activated globally (CONFIG_CMD_MEM). 4906 4907- CONFIG_MX_CYCLIC 4908 Add the "mdc" and "mwc" memory commands. These are cyclic 4909 "md/mw" commands. 4910 Examples: 4911 4912 => mdc.b 10 4 500 4913 This command will print 4 bytes (10,11,12,13) each 500 ms. 4914 4915 => mwc.l 100 12345678 10 4916 This command will write 12345678 to address 100 all 10 ms. 4917 4918 This only takes effect if the memory commands are activated 4919 globally (CONFIG_CMD_MEM). 4920 4921- CONFIG_SKIP_LOWLEVEL_INIT 4922 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4923 low level initializations (like setting up the memory 4924 controller) are omitted and/or U-Boot does not 4925 relocate itself into RAM. 4926 4927 Normally this variable MUST NOT be defined. The only 4928 exception is when U-Boot is loaded (to RAM) by some 4929 other boot loader or by a debugger which performs 4930 these initializations itself. 4931 4932- CONFIG_SPL_BUILD 4933 Modifies the behaviour of start.S when compiling a loader 4934 that is executed before the actual U-Boot. E.g. when 4935 compiling a NAND SPL. 4936 4937- CONFIG_TPL_BUILD 4938 Modifies the behaviour of start.S when compiling a loader 4939 that is executed after the SPL and before the actual U-Boot. 4940 It is loaded by the SPL. 4941 4942- CONFIG_SYS_MPC85XX_NO_RESETVEC 4943 Only for 85xx systems. If this variable is specified, the section 4944 .resetvec is not kept and the section .bootpg is placed in the 4945 previous 4k of the .text section. 4946 4947- CONFIG_ARCH_MAP_SYSMEM 4948 Generally U-Boot (and in particular the md command) uses 4949 effective address. It is therefore not necessary to regard 4950 U-Boot address as virtual addresses that need to be translated 4951 to physical addresses. However, sandbox requires this, since 4952 it maintains its own little RAM buffer which contains all 4953 addressable memory. This option causes some memory accesses 4954 to be mapped through map_sysmem() / unmap_sysmem(). 4955 4956- CONFIG_USE_ARCH_MEMCPY 4957 CONFIG_USE_ARCH_MEMSET 4958 If these options are used a optimized version of memcpy/memset will 4959 be used if available. These functions may be faster under some 4960 conditions but may increase the binary size. 4961 4962- CONFIG_X86_RESET_VECTOR 4963 If defined, the x86 reset vector code is included. This is not 4964 needed when U-Boot is running from Coreboot. 4965 4966- CONFIG_SYS_MPUCLK 4967 Defines the MPU clock speed (in MHz). 4968 4969 NOTE : currently only supported on AM335x platforms. 4970 4971- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4972 Enables the RTC32K OSC on AM33xx based plattforms 4973 4974- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4975 Option to disable subpage write in NAND driver 4976 driver that uses this: 4977 drivers/mtd/nand/davinci_nand.c 4978 4979Freescale QE/FMAN Firmware Support: 4980----------------------------------- 4981 4982The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4983loading of "firmware", which is encoded in the QE firmware binary format. 4984This firmware often needs to be loaded during U-Boot booting, so macros 4985are used to identify the storage device (NOR flash, SPI, etc) and the address 4986within that device. 4987 4988- CONFIG_SYS_FMAN_FW_ADDR 4989 The address in the storage device where the FMAN microcode is located. The 4990 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4991 is also specified. 4992 4993- CONFIG_SYS_QE_FW_ADDR 4994 The address in the storage device where the QE microcode is located. The 4995 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4996 is also specified. 4997 4998- CONFIG_SYS_QE_FMAN_FW_LENGTH 4999 The maximum possible size of the firmware. The firmware binary format 5000 has a field that specifies the actual size of the firmware, but it 5001 might not be possible to read any part of the firmware unless some 5002 local storage is allocated to hold the entire firmware first. 5003 5004- CONFIG_SYS_QE_FMAN_FW_IN_NOR 5005 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 5006 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 5007 virtual address in NOR flash. 5008 5009- CONFIG_SYS_QE_FMAN_FW_IN_NAND 5010 Specifies that QE/FMAN firmware is located in NAND flash. 5011 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 5012 5013- CONFIG_SYS_QE_FMAN_FW_IN_MMC 5014 Specifies that QE/FMAN firmware is located on the primary SD/MMC 5015 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5016 5017- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 5018 Specifies that QE/FMAN firmware is located on the primary SPI 5019 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5020 5021- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 5022 Specifies that QE/FMAN firmware is located in the remote (master) 5023 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 5024 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 5025 window->master inbound window->master LAW->the ucode address in 5026 master's memory space. 5027 5028Freescale Layerscape Management Complex Firmware Support: 5029--------------------------------------------------------- 5030The Freescale Layerscape Management Complex (MC) supports the loading of 5031"firmware". 5032This firmware often needs to be loaded during U-Boot booting, so macros 5033are used to identify the storage device (NOR flash, SPI, etc) and the address 5034within that device. 5035 5036- CONFIG_FSL_MC_ENET 5037 Enable the MC driver for Layerscape SoCs. 5038 5039- CONFIG_SYS_LS_MC_FW_ADDR 5040 The address in the storage device where the firmware is located. The 5041 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro 5042 is also specified. 5043 5044- CONFIG_SYS_LS_MC_FW_LENGTH 5045 The maximum possible size of the firmware. The firmware binary format 5046 has a field that specifies the actual size of the firmware, but it 5047 might not be possible to read any part of the firmware unless some 5048 local storage is allocated to hold the entire firmware first. 5049 5050- CONFIG_SYS_LS_MC_FW_IN_NOR 5051 Specifies that MC firmware is located in NOR flash, mapped as 5052 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the 5053 virtual address in NOR flash. 5054 5055Freescale Layerscape Debug Server Support: 5056------------------------------------------- 5057The Freescale Layerscape Debug Server Support supports the loading of 5058"Debug Server firmware" and triggering SP boot-rom. 5059This firmware often needs to be loaded during U-Boot booting. 5060 5061- CONFIG_FSL_DEBUG_SERVER 5062 Enable the Debug Server for Layerscape SoCs. 5063 5064- CONFIG_SYS_DEBUG_SERVER_DRAM_BLOCK_MIN_SIZE 5065 Define minimum DDR size required for debug server image 5066 5067- CONFIG_SYS_MEM_TOP_HIDE_MIN 5068 Define minimum DDR size to be hided from top of the DDR memory 5069 5070Reproducible builds 5071------------------- 5072 5073In order to achieve reproducible builds, timestamps used in the U-Boot build 5074process have to be set to a fixed value. 5075 5076This is done using the SOURCE_DATE_EPOCH environment variable. 5077SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 5078option for U-Boot or an environment variable in U-Boot. 5079 5080SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 5081 5082Building the Software: 5083====================== 5084 5085Building U-Boot has been tested in several native build environments 5086and in many different cross environments. Of course we cannot support 5087all possibly existing versions of cross development tools in all 5088(potentially obsolete) versions. In case of tool chain problems we 5089recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 5090which is extensively used to build and test U-Boot. 5091 5092If you are not using a native environment, it is assumed that you 5093have GNU cross compiling tools available in your path. In this case, 5094you must set the environment variable CROSS_COMPILE in your shell. 5095Note that no changes to the Makefile or any other source files are 5096necessary. For example using the ELDK on a 4xx CPU, please enter: 5097 5098 $ CROSS_COMPILE=ppc_4xx- 5099 $ export CROSS_COMPILE 5100 5101Note: If you wish to generate Windows versions of the utilities in 5102 the tools directory you can use the MinGW toolchain 5103 (http://www.mingw.org). Set your HOST tools to the MinGW 5104 toolchain and execute 'make tools'. For example: 5105 5106 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 5107 5108 Binaries such as tools/mkimage.exe will be created which can 5109 be executed on computers running Windows. 5110 5111U-Boot is intended to be simple to build. After installing the 5112sources you must configure U-Boot for one specific board type. This 5113is done by typing: 5114 5115 make NAME_defconfig 5116 5117where "NAME_defconfig" is the name of one of the existing configu- 5118rations; see boards.cfg for supported names. 5119 5120Note: for some board special configuration names may exist; check if 5121 additional information is available from the board vendor; for 5122 instance, the TQM823L systems are available without (standard) 5123 or with LCD support. You can select such additional "features" 5124 when choosing the configuration, i. e. 5125 5126 make TQM823L_defconfig 5127 - will configure for a plain TQM823L, i. e. no LCD support 5128 5129 make TQM823L_LCD_defconfig 5130 - will configure for a TQM823L with U-Boot console on LCD 5131 5132 etc. 5133 5134 5135Finally, type "make all", and you should get some working U-Boot 5136images ready for download to / installation on your system: 5137 5138- "u-boot.bin" is a raw binary image 5139- "u-boot" is an image in ELF binary format 5140- "u-boot.srec" is in Motorola S-Record format 5141 5142By default the build is performed locally and the objects are saved 5143in the source directory. One of the two methods can be used to change 5144this behavior and build U-Boot to some external directory: 5145 51461. Add O= to the make command line invocations: 5147 5148 make O=/tmp/build distclean 5149 make O=/tmp/build NAME_defconfig 5150 make O=/tmp/build all 5151 51522. Set environment variable KBUILD_OUTPUT to point to the desired location: 5153 5154 export KBUILD_OUTPUT=/tmp/build 5155 make distclean 5156 make NAME_defconfig 5157 make all 5158 5159Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 5160variable. 5161 5162 5163Please be aware that the Makefiles assume you are using GNU make, so 5164for instance on NetBSD you might need to use "gmake" instead of 5165native "make". 5166 5167 5168If the system board that you have is not listed, then you will need 5169to port U-Boot to your hardware platform. To do this, follow these 5170steps: 5171 51721. Add a new configuration option for your board to the toplevel 5173 "boards.cfg" file, using the existing entries as examples. 5174 Follow the instructions there to keep the boards in order. 51752. Create a new directory to hold your board specific code. Add any 5176 files you need. In your board directory, you will need at least 5177 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 51783. Create a new configuration file "include/configs/<board>.h" for 5179 your board 51803. If you're porting U-Boot to a new CPU, then also create a new 5181 directory to hold your CPU specific code. Add any files you need. 51824. Run "make <board>_defconfig" with your new name. 51835. Type "make", and you should get a working "u-boot.srec" file 5184 to be installed on your target system. 51856. Debug and solve any problems that might arise. 5186 [Of course, this last step is much harder than it sounds.] 5187 5188 5189Testing of U-Boot Modifications, Ports to New Hardware, etc.: 5190============================================================== 5191 5192If you have modified U-Boot sources (for instance added a new board 5193or support for new devices, a new CPU, etc.) you are expected to 5194provide feedback to the other developers. The feedback normally takes 5195the form of a "patch", i. e. a context diff against a certain (latest 5196official or latest in the git repository) version of U-Boot sources. 5197 5198But before you submit such a patch, please verify that your modifi- 5199cation did not break existing code. At least make sure that *ALL* of 5200the supported boards compile WITHOUT ANY compiler warnings. To do so, 5201just run the "MAKEALL" script, which will configure and build U-Boot 5202for ALL supported system. Be warned, this will take a while. You can 5203select which (cross) compiler to use by passing a `CROSS_COMPILE' 5204environment variable to the script, i. e. to use the ELDK cross tools 5205you can type 5206 5207 CROSS_COMPILE=ppc_8xx- MAKEALL 5208 5209or to build on a native PowerPC system you can type 5210 5211 CROSS_COMPILE=' ' MAKEALL 5212 5213When using the MAKEALL script, the default behaviour is to build 5214U-Boot in the source directory. This location can be changed by 5215setting the BUILD_DIR environment variable. Also, for each target 5216built, the MAKEALL script saves two log files (<target>.ERR and 5217<target>.MAKEALL) in the <source dir>/LOG directory. This default 5218location can be changed by setting the MAKEALL_LOGDIR environment 5219variable. For example: 5220 5221 export BUILD_DIR=/tmp/build 5222 export MAKEALL_LOGDIR=/tmp/log 5223 CROSS_COMPILE=ppc_8xx- MAKEALL 5224 5225With the above settings build objects are saved in the /tmp/build, 5226log files are saved in the /tmp/log and the source tree remains clean 5227during the whole build process. 5228 5229 5230See also "U-Boot Porting Guide" below. 5231 5232 5233Monitor Commands - Overview: 5234============================ 5235 5236go - start application at address 'addr' 5237run - run commands in an environment variable 5238bootm - boot application image from memory 5239bootp - boot image via network using BootP/TFTP protocol 5240bootz - boot zImage from memory 5241tftpboot- boot image via network using TFTP protocol 5242 and env variables "ipaddr" and "serverip" 5243 (and eventually "gatewayip") 5244tftpput - upload a file via network using TFTP protocol 5245rarpboot- boot image via network using RARP/TFTP protocol 5246diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 5247loads - load S-Record file over serial line 5248loadb - load binary file over serial line (kermit mode) 5249md - memory display 5250mm - memory modify (auto-incrementing) 5251nm - memory modify (constant address) 5252mw - memory write (fill) 5253cp - memory copy 5254cmp - memory compare 5255crc32 - checksum calculation 5256i2c - I2C sub-system 5257sspi - SPI utility commands 5258base - print or set address offset 5259printenv- print environment variables 5260setenv - set environment variables 5261saveenv - save environment variables to persistent storage 5262protect - enable or disable FLASH write protection 5263erase - erase FLASH memory 5264flinfo - print FLASH memory information 5265nand - NAND memory operations (see doc/README.nand) 5266bdinfo - print Board Info structure 5267iminfo - print header information for application image 5268coninfo - print console devices and informations 5269ide - IDE sub-system 5270loop - infinite loop on address range 5271loopw - infinite write loop on address range 5272mtest - simple RAM test 5273icache - enable or disable instruction cache 5274dcache - enable or disable data cache 5275reset - Perform RESET of the CPU 5276echo - echo args to console 5277version - print monitor version 5278help - print online help 5279? - alias for 'help' 5280 5281 5282Monitor Commands - Detailed Description: 5283======================================== 5284 5285TODO. 5286 5287For now: just type "help <command>". 5288 5289 5290Environment Variables: 5291====================== 5292 5293U-Boot supports user configuration using Environment Variables which 5294can be made persistent by saving to Flash memory. 5295 5296Environment Variables are set using "setenv", printed using 5297"printenv", and saved to Flash using "saveenv". Using "setenv" 5298without a value can be used to delete a variable from the 5299environment. As long as you don't save the environment you are 5300working with an in-memory copy. In case the Flash area containing the 5301environment is erased by accident, a default environment is provided. 5302 5303Some configuration options can be set using Environment Variables. 5304 5305List of environment variables (most likely not complete): 5306 5307 baudrate - see CONFIG_BAUDRATE 5308 5309 bootdelay - see CONFIG_BOOTDELAY 5310 5311 bootcmd - see CONFIG_BOOTCOMMAND 5312 5313 bootargs - Boot arguments when booting an RTOS image 5314 5315 bootfile - Name of the image to load with TFTP 5316 5317 bootm_low - Memory range available for image processing in the bootm 5318 command can be restricted. This variable is given as 5319 a hexadecimal number and defines lowest address allowed 5320 for use by the bootm command. See also "bootm_size" 5321 environment variable. Address defined by "bootm_low" is 5322 also the base of the initial memory mapping for the Linux 5323 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 5324 bootm_mapsize. 5325 5326 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 5327 This variable is given as a hexadecimal number and it 5328 defines the size of the memory region starting at base 5329 address bootm_low that is accessible by the Linux kernel 5330 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 5331 as the default value if it is defined, and bootm_size is 5332 used otherwise. 5333 5334 bootm_size - Memory range available for image processing in the bootm 5335 command can be restricted. This variable is given as 5336 a hexadecimal number and defines the size of the region 5337 allowed for use by the bootm command. See also "bootm_low" 5338 environment variable. 5339 5340 updatefile - Location of the software update file on a TFTP server, used 5341 by the automatic software update feature. Please refer to 5342 documentation in doc/README.update for more details. 5343 5344 autoload - if set to "no" (any string beginning with 'n'), 5345 "bootp" will just load perform a lookup of the 5346 configuration from the BOOTP server, but not try to 5347 load any image using TFTP 5348 5349 autostart - if set to "yes", an image loaded using the "bootp", 5350 "rarpboot", "tftpboot" or "diskboot" commands will 5351 be automatically started (by internally calling 5352 "bootm") 5353 5354 If set to "no", a standalone image passed to the 5355 "bootm" command will be copied to the load address 5356 (and eventually uncompressed), but NOT be started. 5357 This can be used to load and uncompress arbitrary 5358 data. 5359 5360 fdt_high - if set this restricts the maximum address that the 5361 flattened device tree will be copied into upon boot. 5362 For example, if you have a system with 1 GB memory 5363 at physical address 0x10000000, while Linux kernel 5364 only recognizes the first 704 MB as low memory, you 5365 may need to set fdt_high as 0x3C000000 to have the 5366 device tree blob be copied to the maximum address 5367 of the 704 MB low memory, so that Linux kernel can 5368 access it during the boot procedure. 5369 5370 If this is set to the special value 0xFFFFFFFF then 5371 the fdt will not be copied at all on boot. For this 5372 to work it must reside in writable memory, have 5373 sufficient padding on the end of it for u-boot to 5374 add the information it needs into it, and the memory 5375 must be accessible by the kernel. 5376 5377 fdtcontroladdr- if set this is the address of the control flattened 5378 device tree used by U-Boot when CONFIG_OF_CONTROL is 5379 defined. 5380 5381 i2cfast - (PPC405GP|PPC405EP only) 5382 if set to 'y' configures Linux I2C driver for fast 5383 mode (400kHZ). This environment variable is used in 5384 initialization code. So, for changes to be effective 5385 it must be saved and board must be reset. 5386 5387 initrd_high - restrict positioning of initrd images: 5388 If this variable is not set, initrd images will be 5389 copied to the highest possible address in RAM; this 5390 is usually what you want since it allows for 5391 maximum initrd size. If for some reason you want to 5392 make sure that the initrd image is loaded below the 5393 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 5394 variable to a value of "no" or "off" or "0". 5395 Alternatively, you can set it to a maximum upper 5396 address to use (U-Boot will still check that it 5397 does not overwrite the U-Boot stack and data). 5398 5399 For instance, when you have a system with 16 MB 5400 RAM, and want to reserve 4 MB from use by Linux, 5401 you can do this by adding "mem=12M" to the value of 5402 the "bootargs" variable. However, now you must make 5403 sure that the initrd image is placed in the first 5404 12 MB as well - this can be done with 5405 5406 setenv initrd_high 00c00000 5407 5408 If you set initrd_high to 0xFFFFFFFF, this is an 5409 indication to U-Boot that all addresses are legal 5410 for the Linux kernel, including addresses in flash 5411 memory. In this case U-Boot will NOT COPY the 5412 ramdisk at all. This may be useful to reduce the 5413 boot time on your system, but requires that this 5414 feature is supported by your Linux kernel. 5415 5416 ipaddr - IP address; needed for tftpboot command 5417 5418 loadaddr - Default load address for commands like "bootp", 5419 "rarpboot", "tftpboot", "loadb" or "diskboot" 5420 5421 loads_echo - see CONFIG_LOADS_ECHO 5422 5423 serverip - TFTP server IP address; needed for tftpboot command 5424 5425 bootretry - see CONFIG_BOOT_RETRY_TIME 5426 5427 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 5428 5429 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 5430 5431 ethprime - controls which interface is used first. 5432 5433 ethact - controls which interface is currently active. 5434 For example you can do the following 5435 5436 => setenv ethact FEC 5437 => ping 192.168.0.1 # traffic sent on FEC 5438 => setenv ethact SCC 5439 => ping 10.0.0.1 # traffic sent on SCC 5440 5441 ethrotate - When set to "no" U-Boot does not go through all 5442 available network interfaces. 5443 It just stays at the currently selected interface. 5444 5445 netretry - When set to "no" each network operation will 5446 either succeed or fail without retrying. 5447 When set to "once" the network operation will 5448 fail when all the available network interfaces 5449 are tried once without success. 5450 Useful on scripts which control the retry operation 5451 themselves. 5452 5453 npe_ucode - set load address for the NPE microcode 5454 5455 silent_linux - If set then Linux will be told to boot silently, by 5456 changing the console to be empty. If "yes" it will be 5457 made silent. If "no" it will not be made silent. If 5458 unset, then it will be made silent if the U-Boot console 5459 is silent. 5460 5461 tftpsrcport - If this is set, the value is used for TFTP's 5462 UDP source port. 5463 5464 tftpdstport - If this is set, the value is used for TFTP's UDP 5465 destination port instead of the Well Know Port 69. 5466 5467 tftpblocksize - Block size to use for TFTP transfers; if not set, 5468 we use the TFTP server's default block size 5469 5470 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5471 seconds, minimum value is 1000 = 1 second). Defines 5472 when a packet is considered to be lost so it has to 5473 be retransmitted. The default is 5000 = 5 seconds. 5474 Lowering this value may make downloads succeed 5475 faster in networks with high packet loss rates or 5476 with unreliable TFTP servers. 5477 5478 vlan - When set to a value < 4095 the traffic over 5479 Ethernet is encapsulated/received over 802.1q 5480 VLAN tagged frames. 5481 5482The following image location variables contain the location of images 5483used in booting. The "Image" column gives the role of the image and is 5484not an environment variable name. The other columns are environment 5485variable names. "File Name" gives the name of the file on a TFTP 5486server, "RAM Address" gives the location in RAM the image will be 5487loaded to, and "Flash Location" gives the image's address in NOR 5488flash or offset in NAND flash. 5489 5490*Note* - these variables don't have to be defined for all boards, some 5491boards currently use other variables for these purposes, and some 5492boards use these variables for other purposes. 5493 5494Image File Name RAM Address Flash Location 5495----- --------- ----------- -------------- 5496u-boot u-boot u-boot_addr_r u-boot_addr 5497Linux kernel bootfile kernel_addr_r kernel_addr 5498device tree blob fdtfile fdt_addr_r fdt_addr 5499ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5500 5501The following environment variables may be used and automatically 5502updated by the network boot commands ("bootp" and "rarpboot"), 5503depending the information provided by your boot server: 5504 5505 bootfile - see above 5506 dnsip - IP address of your Domain Name Server 5507 dnsip2 - IP address of your secondary Domain Name Server 5508 gatewayip - IP address of the Gateway (Router) to use 5509 hostname - Target hostname 5510 ipaddr - see above 5511 netmask - Subnet Mask 5512 rootpath - Pathname of the root filesystem on the NFS server 5513 serverip - see above 5514 5515 5516There are two special Environment Variables: 5517 5518 serial# - contains hardware identification information such 5519 as type string and/or serial number 5520 ethaddr - Ethernet address 5521 5522These variables can be set only once (usually during manufacturing of 5523the board). U-Boot refuses to delete or overwrite these variables 5524once they have been set once. 5525 5526 5527Further special Environment Variables: 5528 5529 ver - Contains the U-Boot version string as printed 5530 with the "version" command. This variable is 5531 readonly (see CONFIG_VERSION_VARIABLE). 5532 5533 5534Please note that changes to some configuration parameters may take 5535only effect after the next boot (yes, that's just like Windoze :-). 5536 5537 5538Callback functions for environment variables: 5539--------------------------------------------- 5540 5541For some environment variables, the behavior of u-boot needs to change 5542when their values are changed. This functionality allows functions to 5543be associated with arbitrary variables. On creation, overwrite, or 5544deletion, the callback will provide the opportunity for some side 5545effect to happen or for the change to be rejected. 5546 5547The callbacks are named and associated with a function using the 5548U_BOOT_ENV_CALLBACK macro in your board or driver code. 5549 5550These callbacks are associated with variables in one of two ways. The 5551static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5552in the board configuration to a string that defines a list of 5553associations. The list must be in the following format: 5554 5555 entry = variable_name[:callback_name] 5556 list = entry[,list] 5557 5558If the callback name is not specified, then the callback is deleted. 5559Spaces are also allowed anywhere in the list. 5560 5561Callbacks can also be associated by defining the ".callbacks" variable 5562with the same list format above. Any association in ".callbacks" will 5563override any association in the static list. You can define 5564CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5565".callbacks" environment variable in the default or embedded environment. 5566 5567If CONFIG_REGEX is defined, the variable_name above is evaluated as a 5568regular expression. This allows multiple variables to be connected to 5569the same callback without explicitly listing them all out. 5570 5571 5572Command Line Parsing: 5573===================== 5574 5575There are two different command line parsers available with U-Boot: 5576the old "simple" one, and the much more powerful "hush" shell: 5577 5578Old, simple command line parser: 5579-------------------------------- 5580 5581- supports environment variables (through setenv / saveenv commands) 5582- several commands on one line, separated by ';' 5583- variable substitution using "... ${name} ..." syntax 5584- special characters ('$', ';') can be escaped by prefixing with '\', 5585 for example: 5586 setenv bootcmd bootm \${address} 5587- You can also escape text by enclosing in single apostrophes, for example: 5588 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5589 5590Hush shell: 5591----------- 5592 5593- similar to Bourne shell, with control structures like 5594 if...then...else...fi, for...do...done; while...do...done, 5595 until...do...done, ... 5596- supports environment ("global") variables (through setenv / saveenv 5597 commands) and local shell variables (through standard shell syntax 5598 "name=value"); only environment variables can be used with "run" 5599 command 5600 5601General rules: 5602-------------- 5603 5604(1) If a command line (or an environment variable executed by a "run" 5605 command) contains several commands separated by semicolon, and 5606 one of these commands fails, then the remaining commands will be 5607 executed anyway. 5608 5609(2) If you execute several variables with one call to run (i. e. 5610 calling run with a list of variables as arguments), any failing 5611 command will cause "run" to terminate, i. e. the remaining 5612 variables are not executed. 5613 5614Note for Redundant Ethernet Interfaces: 5615======================================= 5616 5617Some boards come with redundant Ethernet interfaces; U-Boot supports 5618such configurations and is capable of automatic selection of a 5619"working" interface when needed. MAC assignment works as follows: 5620 5621Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5622MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5623"eth1addr" (=>eth1), "eth2addr", ... 5624 5625If the network interface stores some valid MAC address (for instance 5626in SROM), this is used as default address if there is NO correspon- 5627ding setting in the environment; if the corresponding environment 5628variable is set, this overrides the settings in the card; that means: 5629 5630o If the SROM has a valid MAC address, and there is no address in the 5631 environment, the SROM's address is used. 5632 5633o If there is no valid address in the SROM, and a definition in the 5634 environment exists, then the value from the environment variable is 5635 used. 5636 5637o If both the SROM and the environment contain a MAC address, and 5638 both addresses are the same, this MAC address is used. 5639 5640o If both the SROM and the environment contain a MAC address, and the 5641 addresses differ, the value from the environment is used and a 5642 warning is printed. 5643 5644o If neither SROM nor the environment contain a MAC address, an error 5645 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5646 a random, locally-assigned MAC is used. 5647 5648If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5649will be programmed into hardware as part of the initialization process. This 5650may be skipped by setting the appropriate 'ethmacskip' environment variable. 5651The naming convention is as follows: 5652"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5653 5654Image Formats: 5655============== 5656 5657U-Boot is capable of booting (and performing other auxiliary operations on) 5658images in two formats: 5659 5660New uImage format (FIT) 5661----------------------- 5662 5663Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5664to Flattened Device Tree). It allows the use of images with multiple 5665components (several kernels, ramdisks, etc.), with contents protected by 5666SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5667 5668 5669Old uImage format 5670----------------- 5671 5672Old image format is based on binary files which can be basically anything, 5673preceded by a special header; see the definitions in include/image.h for 5674details; basically, the header defines the following image properties: 5675 5676* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5677 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5678 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5679 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5680 INTEGRITY). 5681* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5682 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5683 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5684* Compression Type (uncompressed, gzip, bzip2) 5685* Load Address 5686* Entry Point 5687* Image Name 5688* Image Timestamp 5689 5690The header is marked by a special Magic Number, and both the header 5691and the data portions of the image are secured against corruption by 5692CRC32 checksums. 5693 5694 5695Linux Support: 5696============== 5697 5698Although U-Boot should support any OS or standalone application 5699easily, the main focus has always been on Linux during the design of 5700U-Boot. 5701 5702U-Boot includes many features that so far have been part of some 5703special "boot loader" code within the Linux kernel. Also, any 5704"initrd" images to be used are no longer part of one big Linux image; 5705instead, kernel and "initrd" are separate images. This implementation 5706serves several purposes: 5707 5708- the same features can be used for other OS or standalone 5709 applications (for instance: using compressed images to reduce the 5710 Flash memory footprint) 5711 5712- it becomes much easier to port new Linux kernel versions because 5713 lots of low-level, hardware dependent stuff are done by U-Boot 5714 5715- the same Linux kernel image can now be used with different "initrd" 5716 images; of course this also means that different kernel images can 5717 be run with the same "initrd". This makes testing easier (you don't 5718 have to build a new "zImage.initrd" Linux image when you just 5719 change a file in your "initrd"). Also, a field-upgrade of the 5720 software is easier now. 5721 5722 5723Linux HOWTO: 5724============ 5725 5726Porting Linux to U-Boot based systems: 5727--------------------------------------- 5728 5729U-Boot cannot save you from doing all the necessary modifications to 5730configure the Linux device drivers for use with your target hardware 5731(no, we don't intend to provide a full virtual machine interface to 5732Linux :-). 5733 5734But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5735 5736Just make sure your machine specific header file (for instance 5737include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5738Information structure as we define in include/asm-<arch>/u-boot.h, 5739and make sure that your definition of IMAP_ADDR uses the same value 5740as your U-Boot configuration in CONFIG_SYS_IMMR. 5741 5742Note that U-Boot now has a driver model, a unified model for drivers. 5743If you are adding a new driver, plumb it into driver model. If there 5744is no uclass available, you are encouraged to create one. See 5745doc/driver-model. 5746 5747 5748Configuring the Linux kernel: 5749----------------------------- 5750 5751No specific requirements for U-Boot. Make sure you have some root 5752device (initial ramdisk, NFS) for your target system. 5753 5754 5755Building a Linux Image: 5756----------------------- 5757 5758With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5759not used. If you use recent kernel source, a new build target 5760"uImage" will exist which automatically builds an image usable by 5761U-Boot. Most older kernels also have support for a "pImage" target, 5762which was introduced for our predecessor project PPCBoot and uses a 5763100% compatible format. 5764 5765Example: 5766 5767 make TQM850L_defconfig 5768 make oldconfig 5769 make dep 5770 make uImage 5771 5772The "uImage" build target uses a special tool (in 'tools/mkimage') to 5773encapsulate a compressed Linux kernel image with header information, 5774CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5775 5776* build a standard "vmlinux" kernel image (in ELF binary format): 5777 5778* convert the kernel into a raw binary image: 5779 5780 ${CROSS_COMPILE}-objcopy -O binary \ 5781 -R .note -R .comment \ 5782 -S vmlinux linux.bin 5783 5784* compress the binary image: 5785 5786 gzip -9 linux.bin 5787 5788* package compressed binary image for U-Boot: 5789 5790 mkimage -A ppc -O linux -T kernel -C gzip \ 5791 -a 0 -e 0 -n "Linux Kernel Image" \ 5792 -d linux.bin.gz uImage 5793 5794 5795The "mkimage" tool can also be used to create ramdisk images for use 5796with U-Boot, either separated from the Linux kernel image, or 5797combined into one file. "mkimage" encapsulates the images with a 64 5798byte header containing information about target architecture, 5799operating system, image type, compression method, entry points, time 5800stamp, CRC32 checksums, etc. 5801 5802"mkimage" can be called in two ways: to verify existing images and 5803print the header information, or to build new images. 5804 5805In the first form (with "-l" option) mkimage lists the information 5806contained in the header of an existing U-Boot image; this includes 5807checksum verification: 5808 5809 tools/mkimage -l image 5810 -l ==> list image header information 5811 5812The second form (with "-d" option) is used to build a U-Boot image 5813from a "data file" which is used as image payload: 5814 5815 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5816 -n name -d data_file image 5817 -A ==> set architecture to 'arch' 5818 -O ==> set operating system to 'os' 5819 -T ==> set image type to 'type' 5820 -C ==> set compression type 'comp' 5821 -a ==> set load address to 'addr' (hex) 5822 -e ==> set entry point to 'ep' (hex) 5823 -n ==> set image name to 'name' 5824 -d ==> use image data from 'datafile' 5825 5826Right now, all Linux kernels for PowerPC systems use the same load 5827address (0x00000000), but the entry point address depends on the 5828kernel version: 5829 5830- 2.2.x kernels have the entry point at 0x0000000C, 5831- 2.3.x and later kernels have the entry point at 0x00000000. 5832 5833So a typical call to build a U-Boot image would read: 5834 5835 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5836 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5837 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5838 > examples/uImage.TQM850L 5839 Image Name: 2.4.4 kernel for TQM850L 5840 Created: Wed Jul 19 02:34:59 2000 5841 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5842 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5843 Load Address: 0x00000000 5844 Entry Point: 0x00000000 5845 5846To verify the contents of the image (or check for corruption): 5847 5848 -> tools/mkimage -l examples/uImage.TQM850L 5849 Image Name: 2.4.4 kernel for TQM850L 5850 Created: Wed Jul 19 02:34:59 2000 5851 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5852 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5853 Load Address: 0x00000000 5854 Entry Point: 0x00000000 5855 5856NOTE: for embedded systems where boot time is critical you can trade 5857speed for memory and install an UNCOMPRESSED image instead: this 5858needs more space in Flash, but boots much faster since it does not 5859need to be uncompressed: 5860 5861 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5862 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5863 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5864 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5865 > examples/uImage.TQM850L-uncompressed 5866 Image Name: 2.4.4 kernel for TQM850L 5867 Created: Wed Jul 19 02:34:59 2000 5868 Image Type: PowerPC Linux Kernel Image (uncompressed) 5869 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5870 Load Address: 0x00000000 5871 Entry Point: 0x00000000 5872 5873 5874Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5875when your kernel is intended to use an initial ramdisk: 5876 5877 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5878 > -A ppc -O linux -T ramdisk -C gzip \ 5879 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5880 Image Name: Simple Ramdisk Image 5881 Created: Wed Jan 12 14:01:50 2000 5882 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5883 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5884 Load Address: 0x00000000 5885 Entry Point: 0x00000000 5886 5887The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5888option performs the converse operation of the mkimage's second form (the "-d" 5889option). Given an image built by mkimage, the dumpimage extracts a "data file" 5890from the image: 5891 5892 tools/dumpimage -i image -T type -p position data_file 5893 -i ==> extract from the 'image' a specific 'data_file' 5894 -T ==> set image type to 'type' 5895 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5896 5897 5898Installing a Linux Image: 5899------------------------- 5900 5901To downloading a U-Boot image over the serial (console) interface, 5902you must convert the image to S-Record format: 5903 5904 objcopy -I binary -O srec examples/image examples/image.srec 5905 5906The 'objcopy' does not understand the information in the U-Boot 5907image header, so the resulting S-Record file will be relative to 5908address 0x00000000. To load it to a given address, you need to 5909specify the target address as 'offset' parameter with the 'loads' 5910command. 5911 5912Example: install the image to address 0x40100000 (which on the 5913TQM8xxL is in the first Flash bank): 5914 5915 => erase 40100000 401FFFFF 5916 5917 .......... done 5918 Erased 8 sectors 5919 5920 => loads 40100000 5921 ## Ready for S-Record download ... 5922 ~>examples/image.srec 5923 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5924 ... 5925 15989 15990 15991 15992 5926 [file transfer complete] 5927 [connected] 5928 ## Start Addr = 0x00000000 5929 5930 5931You can check the success of the download using the 'iminfo' command; 5932this includes a checksum verification so you can be sure no data 5933corruption happened: 5934 5935 => imi 40100000 5936 5937 ## Checking Image at 40100000 ... 5938 Image Name: 2.2.13 for initrd on TQM850L 5939 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5940 Data Size: 335725 Bytes = 327 kB = 0 MB 5941 Load Address: 00000000 5942 Entry Point: 0000000c 5943 Verifying Checksum ... OK 5944 5945 5946Boot Linux: 5947----------- 5948 5949The "bootm" command is used to boot an application that is stored in 5950memory (RAM or Flash). In case of a Linux kernel image, the contents 5951of the "bootargs" environment variable is passed to the kernel as 5952parameters. You can check and modify this variable using the 5953"printenv" and "setenv" commands: 5954 5955 5956 => printenv bootargs 5957 bootargs=root=/dev/ram 5958 5959 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5960 5961 => printenv bootargs 5962 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5963 5964 => bootm 40020000 5965 ## Booting Linux kernel at 40020000 ... 5966 Image Name: 2.2.13 for NFS on TQM850L 5967 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5968 Data Size: 381681 Bytes = 372 kB = 0 MB 5969 Load Address: 00000000 5970 Entry Point: 0000000c 5971 Verifying Checksum ... OK 5972 Uncompressing Kernel Image ... OK 5973 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:35:17 MEST 2000 5974 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5975 time_init: decrementer frequency = 187500000/60 5976 Calibrating delay loop... 49.77 BogoMIPS 5977 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5978 ... 5979 5980If you want to boot a Linux kernel with initial RAM disk, you pass 5981the memory addresses of both the kernel and the initrd image (PPBCOOT 5982format!) to the "bootm" command: 5983 5984 => imi 40100000 40200000 5985 5986 ## Checking Image at 40100000 ... 5987 Image Name: 2.2.13 for initrd on TQM850L 5988 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5989 Data Size: 335725 Bytes = 327 kB = 0 MB 5990 Load Address: 00000000 5991 Entry Point: 0000000c 5992 Verifying Checksum ... OK 5993 5994 ## Checking Image at 40200000 ... 5995 Image Name: Simple Ramdisk Image 5996 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5997 Data Size: 566530 Bytes = 553 kB = 0 MB 5998 Load Address: 00000000 5999 Entry Point: 00000000 6000 Verifying Checksum ... OK 6001 6002 => bootm 40100000 40200000 6003 ## Booting Linux kernel at 40100000 ... 6004 Image Name: 2.2.13 for initrd on TQM850L 6005 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6006 Data Size: 335725 Bytes = 327 kB = 0 MB 6007 Load Address: 00000000 6008 Entry Point: 0000000c 6009 Verifying Checksum ... OK 6010 Uncompressing Kernel Image ... OK 6011 ## Loading RAMDisk Image at 40200000 ... 6012 Image Name: Simple Ramdisk Image 6013 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 6014 Data Size: 566530 Bytes = 553 kB = 0 MB 6015 Load Address: 00000000 6016 Entry Point: 00000000 6017 Verifying Checksum ... OK 6018 Loading Ramdisk ... OK 6019 Linux version 2.2.13 (wd@denx.local.net) (gcc version 2.95.2 19991024 (release)) #1 Wed Jul 19 02:32:08 MEST 2000 6020 Boot arguments: root=/dev/ram 6021 time_init: decrementer frequency = 187500000/60 6022 Calibrating delay loop... 49.77 BogoMIPS 6023 ... 6024 RAMDISK: Compressed image found at block 0 6025 VFS: Mounted root (ext2 filesystem). 6026 6027 bash# 6028 6029Boot Linux and pass a flat device tree: 6030----------- 6031 6032First, U-Boot must be compiled with the appropriate defines. See the section 6033titled "Linux Kernel Interface" above for a more in depth explanation. The 6034following is an example of how to start a kernel and pass an updated 6035flat device tree: 6036 6037=> print oftaddr 6038oftaddr=0x300000 6039=> print oft 6040oft=oftrees/mpc8540ads.dtb 6041=> tftp $oftaddr $oft 6042Speed: 1000, full duplex 6043Using TSEC0 device 6044TFTP from server 192.168.1.1; our IP address is 192.168.1.101 6045Filename 'oftrees/mpc8540ads.dtb'. 6046Load address: 0x300000 6047Loading: # 6048done 6049Bytes transferred = 4106 (100a hex) 6050=> tftp $loadaddr $bootfile 6051Speed: 1000, full duplex 6052Using TSEC0 device 6053TFTP from server 192.168.1.1; our IP address is 192.168.1.2 6054Filename 'uImage'. 6055Load address: 0x200000 6056Loading:############ 6057done 6058Bytes transferred = 1029407 (fb51f hex) 6059=> print loadaddr 6060loadaddr=200000 6061=> print oftaddr 6062oftaddr=0x300000 6063=> bootm $loadaddr - $oftaddr 6064## Booting image at 00200000 ... 6065 Image Name: Linux-2.6.17-dirty 6066 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6067 Data Size: 1029343 Bytes = 1005.2 kB 6068 Load Address: 00000000 6069 Entry Point: 00000000 6070 Verifying Checksum ... OK 6071 Uncompressing Kernel Image ... OK 6072Booting using flat device tree at 0x300000 6073Using MPC85xx ADS machine description 6074Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 6075[snip] 6076 6077 6078More About U-Boot Image Types: 6079------------------------------ 6080 6081U-Boot supports the following image types: 6082 6083 "Standalone Programs" are directly runnable in the environment 6084 provided by U-Boot; it is expected that (if they behave 6085 well) you can continue to work in U-Boot after return from 6086 the Standalone Program. 6087 "OS Kernel Images" are usually images of some Embedded OS which 6088 will take over control completely. Usually these programs 6089 will install their own set of exception handlers, device 6090 drivers, set up the MMU, etc. - this means, that you cannot 6091 expect to re-enter U-Boot except by resetting the CPU. 6092 "RAMDisk Images" are more or less just data blocks, and their 6093 parameters (address, size) are passed to an OS kernel that is 6094 being started. 6095 "Multi-File Images" contain several images, typically an OS 6096 (Linux) kernel image and one or more data images like 6097 RAMDisks. This construct is useful for instance when you want 6098 to boot over the network using BOOTP etc., where the boot 6099 server provides just a single image file, but you want to get 6100 for instance an OS kernel and a RAMDisk image. 6101 6102 "Multi-File Images" start with a list of image sizes, each 6103 image size (in bytes) specified by an "uint32_t" in network 6104 byte order. This list is terminated by an "(uint32_t)0". 6105 Immediately after the terminating 0 follow the images, one by 6106 one, all aligned on "uint32_t" boundaries (size rounded up to 6107 a multiple of 4 bytes). 6108 6109 "Firmware Images" are binary images containing firmware (like 6110 U-Boot or FPGA images) which usually will be programmed to 6111 flash memory. 6112 6113 "Script files" are command sequences that will be executed by 6114 U-Boot's command interpreter; this feature is especially 6115 useful when you configure U-Boot to use a real shell (hush) 6116 as command interpreter. 6117 6118Booting the Linux zImage: 6119------------------------- 6120 6121On some platforms, it's possible to boot Linux zImage. This is done 6122using the "bootz" command. The syntax of "bootz" command is the same 6123as the syntax of "bootm" command. 6124 6125Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 6126kernel with raw initrd images. The syntax is slightly different, the 6127address of the initrd must be augmented by it's size, in the following 6128format: "<initrd addres>:<initrd size>". 6129 6130 6131Standalone HOWTO: 6132================= 6133 6134One of the features of U-Boot is that you can dynamically load and 6135run "standalone" applications, which can use some resources of 6136U-Boot like console I/O functions or interrupt services. 6137 6138Two simple examples are included with the sources: 6139 6140"Hello World" Demo: 6141------------------- 6142 6143'examples/hello_world.c' contains a small "Hello World" Demo 6144application; it is automatically compiled when you build U-Boot. 6145It's configured to run at address 0x00040004, so you can play with it 6146like that: 6147 6148 => loads 6149 ## Ready for S-Record download ... 6150 ~>examples/hello_world.srec 6151 1 2 3 4 5 6 7 8 9 10 11 ... 6152 [file transfer complete] 6153 [connected] 6154 ## Start Addr = 0x00040004 6155 6156 => go 40004 Hello World! This is a test. 6157 ## Starting application at 0x00040004 ... 6158 Hello World 6159 argc = 7 6160 argv[0] = "40004" 6161 argv[1] = "Hello" 6162 argv[2] = "World!" 6163 argv[3] = "This" 6164 argv[4] = "is" 6165 argv[5] = "a" 6166 argv[6] = "test." 6167 argv[7] = "<NULL>" 6168 Hit any key to exit ... 6169 6170 ## Application terminated, rc = 0x0 6171 6172Another example, which demonstrates how to register a CPM interrupt 6173handler with the U-Boot code, can be found in 'examples/timer.c'. 6174Here, a CPM timer is set up to generate an interrupt every second. 6175The interrupt service routine is trivial, just printing a '.' 6176character, but this is just a demo program. The application can be 6177controlled by the following keys: 6178 6179 ? - print current values og the CPM Timer registers 6180 b - enable interrupts and start timer 6181 e - stop timer and disable interrupts 6182 q - quit application 6183 6184 => loads 6185 ## Ready for S-Record download ... 6186 ~>examples/timer.srec 6187 1 2 3 4 5 6 7 8 9 10 11 ... 6188 [file transfer complete] 6189 [connected] 6190 ## Start Addr = 0x00040004 6191 6192 => go 40004 6193 ## Starting application at 0x00040004 ... 6194 TIMERS=0xfff00980 6195 Using timer 1 6196 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 6197 6198Hit 'b': 6199 [q, b, e, ?] Set interval 1000000 us 6200 Enabling timer 6201Hit '?': 6202 [q, b, e, ?] ........ 6203 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 6204Hit '?': 6205 [q, b, e, ?] . 6206 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 6207Hit '?': 6208 [q, b, e, ?] . 6209 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 6210Hit '?': 6211 [q, b, e, ?] . 6212 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 6213Hit 'e': 6214 [q, b, e, ?] ...Stopping timer 6215Hit 'q': 6216 [q, b, e, ?] ## Application terminated, rc = 0x0 6217 6218 6219Minicom warning: 6220================ 6221 6222Over time, many people have reported problems when trying to use the 6223"minicom" terminal emulation program for serial download. I (wd) 6224consider minicom to be broken, and recommend not to use it. Under 6225Unix, I recommend to use C-Kermit for general purpose use (and 6226especially for kermit binary protocol download ("loadb" command), and 6227use "cu" for S-Record download ("loads" command). See 6228http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 6229for help with kermit. 6230 6231 6232Nevertheless, if you absolutely want to use it try adding this 6233configuration to your "File transfer protocols" section: 6234 6235 Name Program Name U/D FullScr IO-Red. Multi 6236 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 6237 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 6238 6239 6240NetBSD Notes: 6241============= 6242 6243Starting at version 0.9.2, U-Boot supports NetBSD both as host 6244(build U-Boot) and target system (boots NetBSD/mpc8xx). 6245 6246Building requires a cross environment; it is known to work on 6247NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 6248need gmake since the Makefiles are not compatible with BSD make). 6249Note that the cross-powerpc package does not install include files; 6250attempting to build U-Boot will fail because <machine/ansi.h> is 6251missing. This file has to be installed and patched manually: 6252 6253 # cd /usr/pkg/cross/powerpc-netbsd/include 6254 # mkdir powerpc 6255 # ln -s powerpc machine 6256 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 6257 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 6258 6259Native builds *don't* work due to incompatibilities between native 6260and U-Boot include files. 6261 6262Booting assumes that (the first part of) the image booted is a 6263stage-2 loader which in turn loads and then invokes the kernel 6264proper. Loader sources will eventually appear in the NetBSD source 6265tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 6266meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 6267 6268 6269Implementation Internals: 6270========================= 6271 6272The following is not intended to be a complete description of every 6273implementation detail. However, it should help to understand the 6274inner workings of U-Boot and make it easier to port it to custom 6275hardware. 6276 6277 6278Initial Stack, Global Data: 6279--------------------------- 6280 6281The implementation of U-Boot is complicated by the fact that U-Boot 6282starts running out of ROM (flash memory), usually without access to 6283system RAM (because the memory controller is not initialized yet). 6284This means that we don't have writable Data or BSS segments, and BSS 6285is not initialized as zero. To be able to get a C environment working 6286at all, we have to allocate at least a minimal stack. Implementation 6287options for this are defined and restricted by the CPU used: Some CPU 6288models provide on-chip memory (like the IMMR area on MPC8xx and 6289MPC826x processors), on others (parts of) the data cache can be 6290locked as (mis-) used as memory, etc. 6291 6292 Chris Hallinan posted a good summary of these issues to the 6293 U-Boot mailing list: 6294 6295 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 6296 From: "Chris Hallinan" <clh@net1plus.com> 6297 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 6298 ... 6299 6300 Correct me if I'm wrong, folks, but the way I understand it 6301 is this: Using DCACHE as initial RAM for Stack, etc, does not 6302 require any physical RAM backing up the cache. The cleverness 6303 is that the cache is being used as a temporary supply of 6304 necessary storage before the SDRAM controller is setup. It's 6305 beyond the scope of this list to explain the details, but you 6306 can see how this works by studying the cache architecture and 6307 operation in the architecture and processor-specific manuals. 6308 6309 OCM is On Chip Memory, which I believe the 405GP has 4K. It 6310 is another option for the system designer to use as an 6311 initial stack/RAM area prior to SDRAM being available. Either 6312 option should work for you. Using CS 4 should be fine if your 6313 board designers haven't used it for something that would 6314 cause you grief during the initial boot! It is frequently not 6315 used. 6316 6317 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 6318 with your processor/board/system design. The default value 6319 you will find in any recent u-boot distribution in 6320 walnut.h should work for you. I'd set it to a value larger 6321 than your SDRAM module. If you have a 64MB SDRAM module, set 6322 it above 400_0000. Just make sure your board has no resources 6323 that are supposed to respond to that address! That code in 6324 start.S has been around a while and should work as is when 6325 you get the config right. 6326 6327 -Chris Hallinan 6328 DS4.COM, Inc. 6329 6330It is essential to remember this, since it has some impact on the C 6331code for the initialization procedures: 6332 6333* Initialized global data (data segment) is read-only. Do not attempt 6334 to write it. 6335 6336* Do not use any uninitialized global data (or implicitly initialized 6337 as zero data - BSS segment) at all - this is undefined, initiali- 6338 zation is performed later (when relocating to RAM). 6339 6340* Stack space is very limited. Avoid big data buffers or things like 6341 that. 6342 6343Having only the stack as writable memory limits means we cannot use 6344normal global data to share information between the code. But it 6345turned out that the implementation of U-Boot can be greatly 6346simplified by making a global data structure (gd_t) available to all 6347functions. We could pass a pointer to this data as argument to _all_ 6348functions, but this would bloat the code. Instead we use a feature of 6349the GCC compiler (Global Register Variables) to share the data: we 6350place a pointer (gd) to the global data into a register which we 6351reserve for this purpose. 6352 6353When choosing a register for such a purpose we are restricted by the 6354relevant (E)ABI specifications for the current architecture, and by 6355GCC's implementation. 6356 6357For PowerPC, the following registers have specific use: 6358 R1: stack pointer 6359 R2: reserved for system use 6360 R3-R4: parameter passing and return values 6361 R5-R10: parameter passing 6362 R13: small data area pointer 6363 R30: GOT pointer 6364 R31: frame pointer 6365 6366 (U-Boot also uses R12 as internal GOT pointer. r12 6367 is a volatile register so r12 needs to be reset when 6368 going back and forth between asm and C) 6369 6370 ==> U-Boot will use R2 to hold a pointer to the global data 6371 6372 Note: on PPC, we could use a static initializer (since the 6373 address of the global data structure is known at compile time), 6374 but it turned out that reserving a register results in somewhat 6375 smaller code - although the code savings are not that big (on 6376 average for all boards 752 bytes for the whole U-Boot image, 6377 624 text + 127 data). 6378 6379On Blackfin, the normal C ABI (except for P3) is followed as documented here: 6380 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 6381 6382 ==> U-Boot will use P3 to hold a pointer to the global data 6383 6384On ARM, the following registers are used: 6385 6386 R0: function argument word/integer result 6387 R1-R3: function argument word 6388 R9: platform specific 6389 R10: stack limit (used only if stack checking is enabled) 6390 R11: argument (frame) pointer 6391 R12: temporary workspace 6392 R13: stack pointer 6393 R14: link register 6394 R15: program counter 6395 6396 ==> U-Boot will use R9 to hold a pointer to the global data 6397 6398 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 6399 6400On Nios II, the ABI is documented here: 6401 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 6402 6403 ==> U-Boot will use gp to hold a pointer to the global data 6404 6405 Note: on Nios II, we give "-G0" option to gcc and don't use gp 6406 to access small data sections, so gp is free. 6407 6408On NDS32, the following registers are used: 6409 6410 R0-R1: argument/return 6411 R2-R5: argument 6412 R15: temporary register for assembler 6413 R16: trampoline register 6414 R28: frame pointer (FP) 6415 R29: global pointer (GP) 6416 R30: link register (LP) 6417 R31: stack pointer (SP) 6418 PC: program counter (PC) 6419 6420 ==> U-Boot will use R10 to hold a pointer to the global data 6421 6422NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 6423or current versions of GCC may "optimize" the code too much. 6424 6425Memory Management: 6426------------------ 6427 6428U-Boot runs in system state and uses physical addresses, i.e. the 6429MMU is not used either for address mapping nor for memory protection. 6430 6431The available memory is mapped to fixed addresses using the memory 6432controller. In this process, a contiguous block is formed for each 6433memory type (Flash, SDRAM, SRAM), even when it consists of several 6434physical memory banks. 6435 6436U-Boot is installed in the first 128 kB of the first Flash bank (on 6437TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 6438booting and sizing and initializing DRAM, the code relocates itself 6439to the upper end of DRAM. Immediately below the U-Boot code some 6440memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 6441configuration setting]. Below that, a structure with global Board 6442Info data is placed, followed by the stack (growing downward). 6443 6444Additionally, some exception handler code is copied to the low 8 kB 6445of DRAM (0x00000000 ... 0x00001FFF). 6446 6447So a typical memory configuration with 16 MB of DRAM could look like 6448this: 6449 6450 0x0000 0000 Exception Vector code 6451 : 6452 0x0000 1FFF 6453 0x0000 2000 Free for Application Use 6454 : 6455 : 6456 6457 : 6458 : 6459 0x00FB FF20 Monitor Stack (Growing downward) 6460 0x00FB FFAC Board Info Data and permanent copy of global data 6461 0x00FC 0000 Malloc Arena 6462 : 6463 0x00FD FFFF 6464 0x00FE 0000 RAM Copy of Monitor Code 6465 ... eventually: LCD or video framebuffer 6466 ... eventually: pRAM (Protected RAM - unchanged by reset) 6467 0x00FF FFFF [End of RAM] 6468 6469 6470System Initialization: 6471---------------------- 6472 6473In the reset configuration, U-Boot starts at the reset entry point 6474(on most PowerPC systems at address 0x00000100). Because of the reset 6475configuration for CS0# this is a mirror of the on board Flash memory. 6476To be able to re-map memory U-Boot then jumps to its link address. 6477To be able to implement the initialization code in C, a (small!) 6478initial stack is set up in the internal Dual Ported RAM (in case CPUs 6479which provide such a feature like MPC8xx or MPC8260), or in a locked 6480part of the data cache. After that, U-Boot initializes the CPU core, 6481the caches and the SIU. 6482 6483Next, all (potentially) available memory banks are mapped using a 6484preliminary mapping. For example, we put them on 512 MB boundaries 6485(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6486on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6487programmed for SDRAM access. Using the temporary configuration, a 6488simple memory test is run that determines the size of the SDRAM 6489banks. 6490 6491When there is more than one SDRAM bank, and the banks are of 6492different size, the largest is mapped first. For equal size, the first 6493bank (CS2#) is mapped first. The first mapping is always for address 64940x00000000, with any additional banks following immediately to create 6495contiguous memory starting from 0. 6496 6497Then, the monitor installs itself at the upper end of the SDRAM area 6498and allocates memory for use by malloc() and for the global Board 6499Info data; also, the exception vector code is copied to the low RAM 6500pages, and the final stack is set up. 6501 6502Only after this relocation will you have a "normal" C environment; 6503until that you are restricted in several ways, mostly because you are 6504running from ROM, and because the code will have to be relocated to a 6505new address in RAM. 6506 6507 6508U-Boot Porting Guide: 6509---------------------- 6510 6511[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6512list, October 2002] 6513 6514 6515int main(int argc, char *argv[]) 6516{ 6517 sighandler_t no_more_time; 6518 6519 signal(SIGALRM, no_more_time); 6520 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6521 6522 if (available_money > available_manpower) { 6523 Pay consultant to port U-Boot; 6524 return 0; 6525 } 6526 6527 Download latest U-Boot source; 6528 6529 Subscribe to u-boot mailing list; 6530 6531 if (clueless) 6532 email("Hi, I am new to U-Boot, how do I get started?"); 6533 6534 while (learning) { 6535 Read the README file in the top level directory; 6536 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6537 Read applicable doc/*.README; 6538 Read the source, Luke; 6539 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6540 } 6541 6542 if (available_money > toLocalCurrency ($2500)) 6543 Buy a BDI3000; 6544 else 6545 Add a lot of aggravation and time; 6546 6547 if (a similar board exists) { /* hopefully... */ 6548 cp -a board/<similar> board/<myboard> 6549 cp include/configs/<similar>.h include/configs/<myboard>.h 6550 } else { 6551 Create your own board support subdirectory; 6552 Create your own board include/configs/<myboard>.h file; 6553 } 6554 Edit new board/<myboard> files 6555 Edit new include/configs/<myboard>.h 6556 6557 while (!accepted) { 6558 while (!running) { 6559 do { 6560 Add / modify source code; 6561 } until (compiles); 6562 Debug; 6563 if (clueless) 6564 email("Hi, I am having problems..."); 6565 } 6566 Send patch file to the U-Boot email list; 6567 if (reasonable critiques) 6568 Incorporate improvements from email list code review; 6569 else 6570 Defend code as written; 6571 } 6572 6573 return 0; 6574} 6575 6576void no_more_time (int sig) 6577{ 6578 hire_a_guru(); 6579} 6580 6581 6582Coding Standards: 6583----------------- 6584 6585All contributions to U-Boot should conform to the Linux kernel 6586coding style; see the file "Documentation/CodingStyle" and the script 6587"scripts/Lindent" in your Linux kernel source directory. 6588 6589Source files originating from a different project (for example the 6590MTD subsystem) are generally exempt from these guidelines and are not 6591reformatted to ease subsequent migration to newer versions of those 6592sources. 6593 6594Please note that U-Boot is implemented in C (and to some small parts in 6595Assembler); no C++ is used, so please do not use C++ style comments (//) 6596in your code. 6597 6598Please also stick to the following formatting rules: 6599- remove any trailing white space 6600- use TAB characters for indentation and vertical alignment, not spaces 6601- make sure NOT to use DOS '\r\n' line feeds 6602- do not add more than 2 consecutive empty lines to source files 6603- do not add trailing empty lines to source files 6604 6605Submissions which do not conform to the standards may be returned 6606with a request to reformat the changes. 6607 6608 6609Submitting Patches: 6610------------------- 6611 6612Since the number of patches for U-Boot is growing, we need to 6613establish some rules. Submissions which do not conform to these rules 6614may be rejected, even when they contain important and valuable stuff. 6615 6616Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6617 6618Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6619see http://lists.denx.de/mailman/listinfo/u-boot 6620 6621When you send a patch, please include the following information with 6622it: 6623 6624* For bug fixes: a description of the bug and how your patch fixes 6625 this bug. Please try to include a way of demonstrating that the 6626 patch actually fixes something. 6627 6628* For new features: a description of the feature and your 6629 implementation. 6630 6631* A CHANGELOG entry as plaintext (separate from the patch) 6632 6633* For major contributions, your entry to the CREDITS file 6634 6635* When you add support for a new board, don't forget to add a 6636 maintainer e-mail address to the boards.cfg file, too. 6637 6638* If your patch adds new configuration options, don't forget to 6639 document these in the README file. 6640 6641* The patch itself. If you are using git (which is *strongly* 6642 recommended) you can easily generate the patch using the 6643 "git format-patch". If you then use "git send-email" to send it to 6644 the U-Boot mailing list, you will avoid most of the common problems 6645 with some other mail clients. 6646 6647 If you cannot use git, use "diff -purN OLD NEW". If your version of 6648 diff does not support these options, then get the latest version of 6649 GNU diff. 6650 6651 The current directory when running this command shall be the parent 6652 directory of the U-Boot source tree (i. e. please make sure that 6653 your patch includes sufficient directory information for the 6654 affected files). 6655 6656 We prefer patches as plain text. MIME attachments are discouraged, 6657 and compressed attachments must not be used. 6658 6659* If one logical set of modifications affects or creates several 6660 files, all these changes shall be submitted in a SINGLE patch file. 6661 6662* Changesets that contain different, unrelated modifications shall be 6663 submitted as SEPARATE patches, one patch per changeset. 6664 6665 6666Notes: 6667 6668* Before sending the patch, run the MAKEALL script on your patched 6669 source tree and make sure that no errors or warnings are reported 6670 for any of the boards. 6671 6672* Keep your modifications to the necessary minimum: A patch 6673 containing several unrelated changes or arbitrary reformats will be 6674 returned with a request to re-formatting / split it. 6675 6676* If you modify existing code, make sure that your new code does not 6677 add to the memory footprint of the code ;-) Small is beautiful! 6678 When adding new features, these should compile conditionally only 6679 (using #ifdef), and the resulting code with the new feature 6680 disabled must not need more memory than the old code without your 6681 modification. 6682 6683* Remember that there is a size limit of 100 kB per message on the 6684 u-boot mailing list. Bigger patches will be moderated. If they are 6685 reasonable and not too big, they will be acknowledged. But patches 6686 bigger than the size limit should be avoided. 6687