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_794072 685 CONFIG_ARM_ERRATA_761320 686 687 If set, the workarounds for these ARM errata are applied early 688 during U-Boot startup. Note that these options force the 689 workarounds to be applied; no CPU-type/version detection 690 exists, unlike the similar options in the Linux kernel. Do not 691 set these options unless they apply! 692 693 COUNTER_FREQUENCY 694 Generic timer clock source frequency. 695 696 COUNTER_FREQUENCY_REAL 697 Generic timer clock source frequency if the real clock is 698 different from COUNTER_FREQUENCY, and can only be determined 699 at run time. 700 701 NOTE: The following can be machine specific errata. These 702 do have ability to provide rudimentary version and machine 703 specific checks, but expect no product checks. 704 CONFIG_ARM_ERRATA_430973 705 CONFIG_ARM_ERRATA_454179 706 CONFIG_ARM_ERRATA_621766 707 CONFIG_ARM_ERRATA_798870 708 709- Tegra SoC options: 710 CONFIG_TEGRA_SUPPORT_NON_SECURE 711 712 Support executing U-Boot in non-secure (NS) mode. Certain 713 impossible actions will be skipped if the CPU is in NS mode, 714 such as ARM architectural timer initialization. 715 716- Linux Kernel Interface: 717 CONFIG_CLOCKS_IN_MHZ 718 719 U-Boot stores all clock information in Hz 720 internally. For binary compatibility with older Linux 721 kernels (which expect the clocks passed in the 722 bd_info data to be in MHz) the environment variable 723 "clocks_in_mhz" can be defined so that U-Boot 724 converts clock data to MHZ before passing it to the 725 Linux kernel. 726 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 727 "clocks_in_mhz=1" is automatically included in the 728 default environment. 729 730 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 731 732 When transferring memsize parameter to Linux, some versions 733 expect it to be in bytes, others in MB. 734 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 735 736 CONFIG_OF_LIBFDT 737 738 New kernel versions are expecting firmware settings to be 739 passed using flattened device trees (based on open firmware 740 concepts). 741 742 CONFIG_OF_LIBFDT 743 * New libfdt-based support 744 * Adds the "fdt" command 745 * The bootm command automatically updates the fdt 746 747 OF_CPU - The proper name of the cpus node (only required for 748 MPC512X and MPC5xxx based boards). 749 OF_SOC - The proper name of the soc node (only required for 750 MPC512X and MPC5xxx based boards). 751 OF_TBCLK - The timebase frequency. 752 OF_STDOUT_PATH - The path to the console device 753 754 boards with QUICC Engines require OF_QE to set UCC MAC 755 addresses 756 757 CONFIG_OF_BOARD_SETUP 758 759 Board code has addition modification that it wants to make 760 to the flat device tree before handing it off to the kernel 761 762 CONFIG_OF_SYSTEM_SETUP 763 764 Other code has addition modification that it wants to make 765 to the flat device tree before handing it off to the kernel. 766 This causes ft_system_setup() to be called before booting 767 the kernel. 768 769 CONFIG_OF_BOOT_CPU 770 771 This define fills in the correct boot CPU in the boot 772 param header, the default value is zero if undefined. 773 774 CONFIG_OF_IDE_FIXUP 775 776 U-Boot can detect if an IDE device is present or not. 777 If not, and this new config option is activated, U-Boot 778 removes the ATA node from the DTS before booting Linux, 779 so the Linux IDE driver does not probe the device and 780 crash. This is needed for buggy hardware (uc101) where 781 no pull down resistor is connected to the signal IDE5V_DD7. 782 783 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 784 785 This setting is mandatory for all boards that have only one 786 machine type and must be used to specify the machine type 787 number as it appears in the ARM machine registry 788 (see http://www.arm.linux.org.uk/developer/machines/). 789 Only boards that have multiple machine types supported 790 in a single configuration file and the machine type is 791 runtime discoverable, do not have to use this setting. 792 793- vxWorks boot parameters: 794 795 bootvx constructs a valid bootline using the following 796 environments variables: bootfile, ipaddr, serverip, hostname. 797 It loads the vxWorks image pointed bootfile. 798 799 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 800 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 801 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 802 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 803 804 CONFIG_SYS_VXWORKS_ADD_PARAMS 805 806 Add it at the end of the bootline. E.g "u=username pw=secret" 807 808 Note: If a "bootargs" environment is defined, it will overwride 809 the defaults discussed just above. 810 811- Cache Configuration: 812 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 813 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 814 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 815 816- Cache Configuration for ARM: 817 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 818 controller 819 CONFIG_SYS_PL310_BASE - Physical base address of PL310 820 controller register space 821 822- Serial Ports: 823 CONFIG_PL010_SERIAL 824 825 Define this if you want support for Amba PrimeCell PL010 UARTs. 826 827 CONFIG_PL011_SERIAL 828 829 Define this if you want support for Amba PrimeCell PL011 UARTs. 830 831 CONFIG_PL011_CLOCK 832 833 If you have Amba PrimeCell PL011 UARTs, set this variable to 834 the clock speed of the UARTs. 835 836 CONFIG_PL01x_PORTS 837 838 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 839 define this to a list of base addresses for each (supported) 840 port. See e.g. include/configs/versatile.h 841 842 CONFIG_PL011_SERIAL_RLCR 843 844 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 845 have separate receive and transmit line control registers. Set 846 this variable to initialize the extra register. 847 848 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 849 850 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 851 boot loader that has already initialized the UART. Define this 852 variable to flush the UART at init time. 853 854 CONFIG_SERIAL_HW_FLOW_CONTROL 855 856 Define this variable to enable hw flow control in serial driver. 857 Current user of this option is drivers/serial/nsl16550.c driver 858 859- Console Interface: 860 Depending on board, define exactly one serial port 861 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 862 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 863 console by defining CONFIG_8xx_CONS_NONE 864 865 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 866 port routines must be defined elsewhere 867 (i.e. serial_init(), serial_getc(), ...) 868 869 CONFIG_CFB_CONSOLE 870 Enables console device for a color framebuffer. Needs following 871 defines (cf. smiLynxEM, i8042) 872 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 873 (default big endian) 874 VIDEO_HW_RECTFILL graphic chip supports 875 rectangle fill 876 (cf. smiLynxEM) 877 VIDEO_HW_BITBLT graphic chip supports 878 bit-blit (cf. smiLynxEM) 879 VIDEO_VISIBLE_COLS visible pixel columns 880 (cols=pitch) 881 VIDEO_VISIBLE_ROWS visible pixel rows 882 VIDEO_PIXEL_SIZE bytes per pixel 883 VIDEO_DATA_FORMAT graphic data format 884 (0-5, cf. cfb_console.c) 885 VIDEO_FB_ADRS framebuffer address 886 VIDEO_KBD_INIT_FCT keyboard int fct 887 (i.e. i8042_kbd_init()) 888 VIDEO_TSTC_FCT test char fct 889 (i.e. i8042_tstc) 890 VIDEO_GETC_FCT get char fct 891 (i.e. i8042_getc) 892 CONFIG_CONSOLE_CURSOR cursor drawing on/off 893 (requires blink timer 894 cf. i8042.c) 895 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 896 CONFIG_CONSOLE_TIME display time/date info in 897 upper right corner 898 (requires CONFIG_CMD_DATE) 899 CONFIG_VIDEO_LOGO display Linux logo in 900 upper left corner 901 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 902 linux_logo.h for logo. 903 Requires CONFIG_VIDEO_LOGO 904 CONFIG_CONSOLE_EXTRA_INFO 905 additional board info beside 906 the logo 907 908 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 909 a limited number of ANSI escape sequences (cursor control, 910 erase functions and limited graphics rendition control). 911 912 When CONFIG_CFB_CONSOLE is defined, video console is 913 default i/o. Serial console can be forced with 914 environment 'console=serial'. 915 916 When CONFIG_SILENT_CONSOLE is defined, all console 917 messages (by U-Boot and Linux!) can be silenced with 918 the "silent" environment variable. See 919 doc/README.silent for more information. 920 921 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 922 is 0x00. 923 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 924 is 0xa0. 925 926- Console Baudrate: 927 CONFIG_BAUDRATE - in bps 928 Select one of the baudrates listed in 929 CONFIG_SYS_BAUDRATE_TABLE, see below. 930 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 931 932- Console Rx buffer length 933 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 934 the maximum receive buffer length for the SMC. 935 This option is actual only for 82xx and 8xx possible. 936 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 937 must be defined, to setup the maximum idle timeout for 938 the SMC. 939 940- Pre-Console Buffer: 941 Prior to the console being initialised (i.e. serial UART 942 initialised etc) all console output is silently discarded. 943 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 944 buffer any console messages prior to the console being 945 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 946 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 947 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 948 bytes are output before the console is initialised, the 949 earlier bytes are discarded. 950 951 'Sane' compilers will generate smaller code if 952 CONFIG_PRE_CON_BUF_SZ is a power of 2 953 954- Safe printf() functions 955 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 956 the printf() functions. These are defined in 957 include/vsprintf.h and include snprintf(), vsnprintf() and 958 so on. Code size increase is approximately 300-500 bytes. 959 If this option is not given then these functions will 960 silently discard their buffer size argument - this means 961 you are not getting any overflow checking in this case. 962 963- Boot Delay: CONFIG_BOOTDELAY - in seconds 964 Delay before automatically booting the default image; 965 set to -1 to disable autoboot. 966 set to -2 to autoboot with no delay and not check for abort 967 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 968 969 See doc/README.autoboot for these options that 970 work with CONFIG_BOOTDELAY. None are required. 971 CONFIG_BOOT_RETRY_TIME 972 CONFIG_BOOT_RETRY_MIN 973 CONFIG_AUTOBOOT_KEYED 974 CONFIG_AUTOBOOT_PROMPT 975 CONFIG_AUTOBOOT_DELAY_STR 976 CONFIG_AUTOBOOT_STOP_STR 977 CONFIG_AUTOBOOT_DELAY_STR2 978 CONFIG_AUTOBOOT_STOP_STR2 979 CONFIG_ZERO_BOOTDELAY_CHECK 980 CONFIG_RESET_TO_RETRY 981 982- Autoboot Command: 983 CONFIG_BOOTCOMMAND 984 Only needed when CONFIG_BOOTDELAY is enabled; 985 define a command string that is automatically executed 986 when no character is read on the console interface 987 within "Boot Delay" after reset. 988 989 CONFIG_BOOTARGS 990 This can be used to pass arguments to the bootm 991 command. The value of CONFIG_BOOTARGS goes into the 992 environment value "bootargs". 993 994 CONFIG_RAMBOOT and CONFIG_NFSBOOT 995 The value of these goes into the environment as 996 "ramboot" and "nfsboot" respectively, and can be used 997 as a convenience, when switching between booting from 998 RAM and NFS. 999 1000- Bootcount: 1001 CONFIG_BOOTCOUNT_LIMIT 1002 Implements a mechanism for detecting a repeating reboot 1003 cycle, see: 1004 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 1005 1006 CONFIG_BOOTCOUNT_ENV 1007 If no softreset save registers are found on the hardware 1008 "bootcount" is stored in the environment. To prevent a 1009 saveenv on all reboots, the environment variable 1010 "upgrade_available" is used. If "upgrade_available" is 1011 0, "bootcount" is always 0, if "upgrade_available" is 1012 1 "bootcount" is incremented in the environment. 1013 So the Userspace Applikation must set the "upgrade_available" 1014 and "bootcount" variable to 0, if a boot was successfully. 1015 1016- Pre-Boot Commands: 1017 CONFIG_PREBOOT 1018 1019 When this option is #defined, the existence of the 1020 environment variable "preboot" will be checked 1021 immediately before starting the CONFIG_BOOTDELAY 1022 countdown and/or running the auto-boot command resp. 1023 entering interactive mode. 1024 1025 This feature is especially useful when "preboot" is 1026 automatically generated or modified. For an example 1027 see the LWMON board specific code: here "preboot" is 1028 modified when the user holds down a certain 1029 combination of keys on the (special) keyboard when 1030 booting the systems 1031 1032- Serial Download Echo Mode: 1033 CONFIG_LOADS_ECHO 1034 If defined to 1, all characters received during a 1035 serial download (using the "loads" command) are 1036 echoed back. This might be needed by some terminal 1037 emulations (like "cu"), but may as well just take 1038 time on others. This setting #define's the initial 1039 value of the "loads_echo" environment variable. 1040 1041- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 1042 CONFIG_KGDB_BAUDRATE 1043 Select one of the baudrates listed in 1044 CONFIG_SYS_BAUDRATE_TABLE, see below. 1045 1046- Monitor Functions: 1047 Monitor commands can be included or excluded 1048 from the build by using the #include files 1049 <config_cmd_all.h> and #undef'ing unwanted 1050 commands, or using <config_cmd_default.h> 1051 and augmenting with additional #define's 1052 for wanted commands. 1053 1054 The default command configuration includes all commands 1055 except those marked below with a "*". 1056 1057 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 1058 CONFIG_CMD_ASKENV * ask for env variable 1059 CONFIG_CMD_BDI bdinfo 1060 CONFIG_CMD_BEDBUG * Include BedBug Debugger 1061 CONFIG_CMD_BMP * BMP support 1062 CONFIG_CMD_BSP * Board specific commands 1063 CONFIG_CMD_BOOTD bootd 1064 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 1065 CONFIG_CMD_CACHE * icache, dcache 1066 CONFIG_CMD_CLK * clock command support 1067 CONFIG_CMD_CONSOLE coninfo 1068 CONFIG_CMD_CRC32 * crc32 1069 CONFIG_CMD_DATE * support for RTC, date/time... 1070 CONFIG_CMD_DHCP * DHCP support 1071 CONFIG_CMD_DIAG * Diagnostics 1072 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 1073 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 1074 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 1075 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 1076 CONFIG_CMD_DTT * Digital Therm and Thermostat 1077 CONFIG_CMD_ECHO echo arguments 1078 CONFIG_CMD_EDITENV edit env variable 1079 CONFIG_CMD_EEPROM * EEPROM read/write support 1080 CONFIG_CMD_ELF * bootelf, bootvx 1081 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 1082 CONFIG_CMD_ENV_FLAGS * display details about env flags 1083 CONFIG_CMD_ENV_EXISTS * check existence of env variable 1084 CONFIG_CMD_EXPORTENV * export the environment 1085 CONFIG_CMD_EXT2 * ext2 command support 1086 CONFIG_CMD_EXT4 * ext4 command support 1087 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 1088 that work for multiple fs types 1089 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 1090 CONFIG_CMD_SAVEENV saveenv 1091 CONFIG_CMD_FDC * Floppy Disk Support 1092 CONFIG_CMD_FAT * FAT command support 1093 CONFIG_CMD_FLASH flinfo, erase, protect 1094 CONFIG_CMD_FPGA FPGA device initialization support 1095 CONFIG_CMD_FUSE * Device fuse support 1096 CONFIG_CMD_GETTIME * Get time since boot 1097 CONFIG_CMD_GO * the 'go' command (exec code) 1098 CONFIG_CMD_GREPENV * search environment 1099 CONFIG_CMD_HASH * calculate hash / digest 1100 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 1101 CONFIG_CMD_I2C * I2C serial bus support 1102 CONFIG_CMD_IDE * IDE harddisk support 1103 CONFIG_CMD_IMI iminfo 1104 CONFIG_CMD_IMLS List all images found in NOR flash 1105 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1106 CONFIG_CMD_IMMAP * IMMR dump support 1107 CONFIG_CMD_IOTRACE * I/O tracing for debugging 1108 CONFIG_CMD_IMPORTENV * import an environment 1109 CONFIG_CMD_INI * import data from an ini file into the env 1110 CONFIG_CMD_IRQ * irqinfo 1111 CONFIG_CMD_ITEST Integer/string test of 2 values 1112 CONFIG_CMD_JFFS2 * JFFS2 Support 1113 CONFIG_CMD_KGDB * kgdb 1114 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1115 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1116 (169.254.*.*) 1117 CONFIG_CMD_LOADB loadb 1118 CONFIG_CMD_LOADS loads 1119 CONFIG_CMD_MD5SUM * print md5 message digest 1120 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1121 CONFIG_CMD_MEMINFO * Display detailed memory information 1122 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1123 loop, loopw 1124 CONFIG_CMD_MEMTEST * mtest 1125 CONFIG_CMD_MISC Misc functions like sleep etc 1126 CONFIG_CMD_MMC * MMC memory mapped support 1127 CONFIG_CMD_MII * MII utility commands 1128 CONFIG_CMD_MTDPARTS * MTD partition support 1129 CONFIG_CMD_NAND * NAND support 1130 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1131 CONFIG_CMD_NFS NFS support 1132 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1133 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1134 CONFIG_CMD_PCI * pciinfo 1135 CONFIG_CMD_PCMCIA * PCMCIA support 1136 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1137 host 1138 CONFIG_CMD_PORTIO * Port I/O 1139 CONFIG_CMD_READ * Read raw data from partition 1140 CONFIG_CMD_REGINFO * Register dump 1141 CONFIG_CMD_RUN run command in env variable 1142 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1143 CONFIG_CMD_SAVES * save S record dump 1144 CONFIG_CMD_SCSI * SCSI Support 1145 CONFIG_CMD_SDRAM * print SDRAM configuration information 1146 (requires CONFIG_CMD_I2C) 1147 CONFIG_CMD_SETGETDCR Support for DCR Register access 1148 (4xx only) 1149 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1150 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1151 (requires CONFIG_CMD_MEMORY) 1152 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1153 CONFIG_CMD_SOURCE "source" command Support 1154 CONFIG_CMD_SPI * SPI serial bus support 1155 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1156 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1157 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1158 CONFIG_CMD_TIMER * access to the system tick timer 1159 CONFIG_CMD_USB * USB support 1160 CONFIG_CMD_CDP * Cisco Discover Protocol support 1161 CONFIG_CMD_MFSL * Microblaze FSL support 1162 CONFIG_CMD_XIMG Load part of Multi Image 1163 CONFIG_CMD_UUID * Generate random UUID or GUID string 1164 1165 EXAMPLE: If you want all functions except of network 1166 support you can write: 1167 1168 #include "config_cmd_all.h" 1169 #undef CONFIG_CMD_NET 1170 1171 Other Commands: 1172 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1173 1174 Note: Don't enable the "icache" and "dcache" commands 1175 (configuration option CONFIG_CMD_CACHE) unless you know 1176 what you (and your U-Boot users) are doing. Data 1177 cache cannot be enabled on systems like the 8xx or 1178 8260 (where accesses to the IMMR region must be 1179 uncached), and it cannot be disabled on all other 1180 systems where we (mis-) use the data cache to hold an 1181 initial stack and some data. 1182 1183 1184 XXX - this list needs to get updated! 1185 1186- Regular expression support: 1187 CONFIG_REGEX 1188 If this variable is defined, U-Boot is linked against 1189 the SLRE (Super Light Regular Expression) library, 1190 which adds regex support to some commands, as for 1191 example "env grep" and "setexpr". 1192 1193- Device tree: 1194 CONFIG_OF_CONTROL 1195 If this variable is defined, U-Boot will use a device tree 1196 to configure its devices, instead of relying on statically 1197 compiled #defines in the board file. This option is 1198 experimental and only available on a few boards. The device 1199 tree is available in the global data as gd->fdt_blob. 1200 1201 U-Boot needs to get its device tree from somewhere. This can 1202 be done using one of the two options below: 1203 1204 CONFIG_OF_EMBED 1205 If this variable is defined, U-Boot will embed a device tree 1206 binary in its image. This device tree file should be in the 1207 board directory and called <soc>-<board>.dts. The binary file 1208 is then picked up in board_init_f() and made available through 1209 the global data structure as gd->blob. 1210 1211 CONFIG_OF_SEPARATE 1212 If this variable is defined, U-Boot will build a device tree 1213 binary. It will be called u-boot.dtb. Architecture-specific 1214 code will locate it at run-time. Generally this works by: 1215 1216 cat u-boot.bin u-boot.dtb >image.bin 1217 1218 and in fact, U-Boot does this for you, creating a file called 1219 u-boot-dtb.bin which is useful in the common case. You can 1220 still use the individual files if you need something more 1221 exotic. 1222 1223- Watchdog: 1224 CONFIG_WATCHDOG 1225 If this variable is defined, it enables watchdog 1226 support for the SoC. There must be support in the SoC 1227 specific code for a watchdog. For the 8xx and 8260 1228 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1229 register. When supported for a specific SoC is 1230 available, then no further board specific code should 1231 be needed to use it. 1232 1233 CONFIG_HW_WATCHDOG 1234 When using a watchdog circuitry external to the used 1235 SoC, then define this variable and provide board 1236 specific code for the "hw_watchdog_reset" function. 1237 1238 CONFIG_AT91_HW_WDT_TIMEOUT 1239 specify the timeout in seconds. default 2 seconds. 1240 1241- U-Boot Version: 1242 CONFIG_VERSION_VARIABLE 1243 If this variable is defined, an environment variable 1244 named "ver" is created by U-Boot showing the U-Boot 1245 version as printed by the "version" command. 1246 Any change to this variable will be reverted at the 1247 next reset. 1248 1249- Real-Time Clock: 1250 1251 When CONFIG_CMD_DATE is selected, the type of the RTC 1252 has to be selected, too. Define exactly one of the 1253 following options: 1254 1255 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1256 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1257 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1258 CONFIG_RTC_MC146818 - use MC146818 RTC 1259 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1260 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1261 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1262 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1263 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1264 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1265 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1266 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1267 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1268 RV3029 RTC. 1269 1270 Note that if the RTC uses I2C, then the I2C interface 1271 must also be configured. See I2C Support, below. 1272 1273- GPIO Support: 1274 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1275 1276 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1277 chip-ngpio pairs that tell the PCA953X driver the number of 1278 pins supported by a particular chip. 1279 1280 Note that if the GPIO device uses I2C, then the I2C interface 1281 must also be configured. See I2C Support, below. 1282 1283- I/O tracing: 1284 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1285 accesses and can checksum them or write a list of them out 1286 to memory. See the 'iotrace' command for details. This is 1287 useful for testing device drivers since it can confirm that 1288 the driver behaves the same way before and after a code 1289 change. Currently this is supported on sandbox and arm. To 1290 add support for your architecture, add '#include <iotrace.h>' 1291 to the bottom of arch/<arch>/include/asm/io.h and test. 1292 1293 Example output from the 'iotrace stats' command is below. 1294 Note that if the trace buffer is exhausted, the checksum will 1295 still continue to operate. 1296 1297 iotrace is enabled 1298 Start: 10000000 (buffer start address) 1299 Size: 00010000 (buffer size) 1300 Offset: 00000120 (current buffer offset) 1301 Output: 10000120 (start + offset) 1302 Count: 00000018 (number of trace records) 1303 CRC32: 9526fb66 (CRC32 of all trace records) 1304 1305- Timestamp Support: 1306 1307 When CONFIG_TIMESTAMP is selected, the timestamp 1308 (date and time) of an image is printed by image 1309 commands like bootm or iminfo. This option is 1310 automatically enabled when you select CONFIG_CMD_DATE . 1311 1312- Partition Labels (disklabels) Supported: 1313 Zero or more of the following: 1314 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1315 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1316 Intel architecture, USB sticks, etc. 1317 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1318 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1319 bootloader. Note 2TB partition limit; see 1320 disk/part_efi.c 1321 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1322 1323 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1324 CONFIG_CMD_SCSI) you must configure support for at 1325 least one non-MTD partition type as well. 1326 1327- IDE Reset method: 1328 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1329 board configurations files but used nowhere! 1330 1331 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1332 be performed by calling the function 1333 ide_set_reset(int reset) 1334 which has to be defined in a board specific file 1335 1336- ATAPI Support: 1337 CONFIG_ATAPI 1338 1339 Set this to enable ATAPI support. 1340 1341- LBA48 Support 1342 CONFIG_LBA48 1343 1344 Set this to enable support for disks larger than 137GB 1345 Also look at CONFIG_SYS_64BIT_LBA. 1346 Whithout these , LBA48 support uses 32bit variables and will 'only' 1347 support disks up to 2.1TB. 1348 1349 CONFIG_SYS_64BIT_LBA: 1350 When enabled, makes the IDE subsystem use 64bit sector addresses. 1351 Default is 32bit. 1352 1353- SCSI Support: 1354 At the moment only there is only support for the 1355 SYM53C8XX SCSI controller; define 1356 CONFIG_SCSI_SYM53C8XX to enable it. 1357 1358 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1359 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1360 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1361 maximum numbers of LUNs, SCSI ID's and target 1362 devices. 1363 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1364 1365 The environment variable 'scsidevs' is set to the number of 1366 SCSI devices found during the last scan. 1367 1368- NETWORK Support (PCI): 1369 CONFIG_E1000 1370 Support for Intel 8254x/8257x gigabit chips. 1371 1372 CONFIG_E1000_SPI 1373 Utility code for direct access to the SPI bus on Intel 8257x. 1374 This does not do anything useful unless you set at least one 1375 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1376 1377 CONFIG_E1000_SPI_GENERIC 1378 Allow generic access to the SPI bus on the Intel 8257x, for 1379 example with the "sspi" command. 1380 1381 CONFIG_CMD_E1000 1382 Management command for E1000 devices. When used on devices 1383 with SPI support you can reprogram the EEPROM from U-Boot. 1384 1385 CONFIG_E1000_FALLBACK_MAC 1386 default MAC for empty EEPROM after production. 1387 1388 CONFIG_EEPRO100 1389 Support for Intel 82557/82559/82559ER chips. 1390 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1391 write routine for first time initialisation. 1392 1393 CONFIG_TULIP 1394 Support for Digital 2114x chips. 1395 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1396 modem chip initialisation (KS8761/QS6611). 1397 1398 CONFIG_NATSEMI 1399 Support for National dp83815 chips. 1400 1401 CONFIG_NS8382X 1402 Support for National dp8382[01] gigabit chips. 1403 1404- NETWORK Support (other): 1405 1406 CONFIG_DRIVER_AT91EMAC 1407 Support for AT91RM9200 EMAC. 1408 1409 CONFIG_RMII 1410 Define this to use reduced MII inteface 1411 1412 CONFIG_DRIVER_AT91EMAC_QUIET 1413 If this defined, the driver is quiet. 1414 The driver doen't show link status messages. 1415 1416 CONFIG_CALXEDA_XGMAC 1417 Support for the Calxeda XGMAC device 1418 1419 CONFIG_LAN91C96 1420 Support for SMSC's LAN91C96 chips. 1421 1422 CONFIG_LAN91C96_BASE 1423 Define this to hold the physical address 1424 of the LAN91C96's I/O space 1425 1426 CONFIG_LAN91C96_USE_32_BIT 1427 Define this to enable 32 bit addressing 1428 1429 CONFIG_SMC91111 1430 Support for SMSC's LAN91C111 chip 1431 1432 CONFIG_SMC91111_BASE 1433 Define this to hold the physical address 1434 of the device (I/O space) 1435 1436 CONFIG_SMC_USE_32_BIT 1437 Define this if data bus is 32 bits 1438 1439 CONFIG_SMC_USE_IOFUNCS 1440 Define this to use i/o functions instead of macros 1441 (some hardware wont work with macros) 1442 1443 CONFIG_DRIVER_TI_EMAC 1444 Support for davinci emac 1445 1446 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1447 Define this if you have more then 3 PHYs. 1448 1449 CONFIG_FTGMAC100 1450 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1451 1452 CONFIG_FTGMAC100_EGIGA 1453 Define this to use GE link update with gigabit PHY. 1454 Define this if FTGMAC100 is connected to gigabit PHY. 1455 If your system has 10/100 PHY only, it might not occur 1456 wrong behavior. Because PHY usually return timeout or 1457 useless data when polling gigabit status and gigabit 1458 control registers. This behavior won't affect the 1459 correctnessof 10/100 link speed update. 1460 1461 CONFIG_SMC911X 1462 Support for SMSC's LAN911x and LAN921x chips 1463 1464 CONFIG_SMC911X_BASE 1465 Define this to hold the physical address 1466 of the device (I/O space) 1467 1468 CONFIG_SMC911X_32_BIT 1469 Define this if data bus is 32 bits 1470 1471 CONFIG_SMC911X_16_BIT 1472 Define this if data bus is 16 bits. If your processor 1473 automatically converts one 32 bit word to two 16 bit 1474 words you may also try CONFIG_SMC911X_32_BIT. 1475 1476 CONFIG_SH_ETHER 1477 Support for Renesas on-chip Ethernet controller 1478 1479 CONFIG_SH_ETHER_USE_PORT 1480 Define the number of ports to be used 1481 1482 CONFIG_SH_ETHER_PHY_ADDR 1483 Define the ETH PHY's address 1484 1485 CONFIG_SH_ETHER_CACHE_WRITEBACK 1486 If this option is set, the driver enables cache flush. 1487 1488- PWM Support: 1489 CONFIG_PWM_IMX 1490 Support for PWM modul on the imx6. 1491 1492- TPM Support: 1493 CONFIG_TPM 1494 Support TPM devices. 1495 1496 CONFIG_TPM_TIS_I2C 1497 Support for i2c bus TPM devices. Only one device 1498 per system is supported at this time. 1499 1500 CONFIG_TPM_TIS_I2C_BUS_NUMBER 1501 Define the the i2c bus number for the TPM device 1502 1503 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS 1504 Define the TPM's address on the i2c bus 1505 1506 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1507 Define the burst count bytes upper limit 1508 1509 CONFIG_TPM_ATMEL_TWI 1510 Support for Atmel TWI TPM device. Requires I2C support. 1511 1512 CONFIG_TPM_TIS_LPC 1513 Support for generic parallel port TPM devices. Only one device 1514 per system is supported at this time. 1515 1516 CONFIG_TPM_TIS_BASE_ADDRESS 1517 Base address where the generic TPM device is mapped 1518 to. Contemporary x86 systems usually map it at 1519 0xfed40000. 1520 1521 CONFIG_CMD_TPM 1522 Add tpm monitor functions. 1523 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1524 provides monitor access to authorized functions. 1525 1526 CONFIG_TPM 1527 Define this to enable the TPM support library which provides 1528 functional interfaces to some TPM commands. 1529 Requires support for a TPM device. 1530 1531 CONFIG_TPM_AUTH_SESSIONS 1532 Define this to enable authorized functions in the TPM library. 1533 Requires CONFIG_TPM and CONFIG_SHA1. 1534 1535- USB Support: 1536 At the moment only the UHCI host controller is 1537 supported (PIP405, MIP405, MPC5200); define 1538 CONFIG_USB_UHCI to enable it. 1539 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1540 and define CONFIG_USB_STORAGE to enable the USB 1541 storage devices. 1542 Note: 1543 Supported are USB Keyboards and USB Floppy drives 1544 (TEAC FD-05PUB). 1545 MPC5200 USB requires additional defines: 1546 CONFIG_USB_CLOCK 1547 for 528 MHz Clock: 0x0001bbbb 1548 CONFIG_PSC3_USB 1549 for USB on PSC3 1550 CONFIG_USB_CONFIG 1551 for differential drivers: 0x00001000 1552 for single ended drivers: 0x00005000 1553 for differential drivers on PSC3: 0x00000100 1554 for single ended drivers on PSC3: 0x00004100 1555 CONFIG_SYS_USB_EVENT_POLL 1556 May be defined to allow interrupt polling 1557 instead of using asynchronous interrupts 1558 1559 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1560 txfilltuning field in the EHCI controller on reset. 1561 1562 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1563 HW module registers. 1564 1565- USB Device: 1566 Define the below if you wish to use the USB console. 1567 Once firmware is rebuilt from a serial console issue the 1568 command "setenv stdin usbtty; setenv stdout usbtty" and 1569 attach your USB cable. The Unix command "dmesg" should print 1570 it has found a new device. The environment variable usbtty 1571 can be set to gserial or cdc_acm to enable your device to 1572 appear to a USB host as a Linux gserial device or a 1573 Common Device Class Abstract Control Model serial device. 1574 If you select usbtty = gserial you should be able to enumerate 1575 a Linux host by 1576 # modprobe usbserial vendor=0xVendorID product=0xProductID 1577 else if using cdc_acm, simply setting the environment 1578 variable usbtty to be cdc_acm should suffice. The following 1579 might be defined in YourBoardName.h 1580 1581 CONFIG_USB_DEVICE 1582 Define this to build a UDC device 1583 1584 CONFIG_USB_TTY 1585 Define this to have a tty type of device available to 1586 talk to the UDC device 1587 1588 CONFIG_USBD_HS 1589 Define this to enable the high speed support for usb 1590 device and usbtty. If this feature is enabled, a routine 1591 int is_usbd_high_speed(void) 1592 also needs to be defined by the driver to dynamically poll 1593 whether the enumeration has succeded at high speed or full 1594 speed. 1595 1596 CONFIG_SYS_CONSOLE_IS_IN_ENV 1597 Define this if you want stdin, stdout &/or stderr to 1598 be set to usbtty. 1599 1600 mpc8xx: 1601 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1602 Derive USB clock from external clock "blah" 1603 - CONFIG_SYS_USB_EXTC_CLK 0x02 1604 1605 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1606 Derive USB clock from brgclk 1607 - CONFIG_SYS_USB_BRG_CLK 0x04 1608 1609 If you have a USB-IF assigned VendorID then you may wish to 1610 define your own vendor specific values either in BoardName.h 1611 or directly in usbd_vendor_info.h. If you don't define 1612 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1613 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1614 should pretend to be a Linux device to it's target host. 1615 1616 CONFIG_USBD_MANUFACTURER 1617 Define this string as the name of your company for 1618 - CONFIG_USBD_MANUFACTURER "my company" 1619 1620 CONFIG_USBD_PRODUCT_NAME 1621 Define this string as the name of your product 1622 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1623 1624 CONFIG_USBD_VENDORID 1625 Define this as your assigned Vendor ID from the USB 1626 Implementors Forum. This *must* be a genuine Vendor ID 1627 to avoid polluting the USB namespace. 1628 - CONFIG_USBD_VENDORID 0xFFFF 1629 1630 CONFIG_USBD_PRODUCTID 1631 Define this as the unique Product ID 1632 for your device 1633 - CONFIG_USBD_PRODUCTID 0xFFFF 1634 1635- ULPI Layer Support: 1636 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1637 the generic ULPI layer. The generic layer accesses the ULPI PHY 1638 via the platform viewport, so you need both the genric layer and 1639 the viewport enabled. Currently only Chipidea/ARC based 1640 viewport is supported. 1641 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1642 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1643 If your ULPI phy needs a different reference clock than the 1644 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1645 the appropriate value in Hz. 1646 1647- MMC Support: 1648 The MMC controller on the Intel PXA is supported. To 1649 enable this define CONFIG_MMC. The MMC can be 1650 accessed from the boot prompt by mapping the device 1651 to physical memory similar to flash. Command line is 1652 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1653 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1654 1655 CONFIG_SH_MMCIF 1656 Support for Renesas on-chip MMCIF controller 1657 1658 CONFIG_SH_MMCIF_ADDR 1659 Define the base address of MMCIF registers 1660 1661 CONFIG_SH_MMCIF_CLK 1662 Define the clock frequency for MMCIF 1663 1664 CONFIG_GENERIC_MMC 1665 Enable the generic MMC driver 1666 1667 CONFIG_SUPPORT_EMMC_BOOT 1668 Enable some additional features of the eMMC boot partitions. 1669 1670 CONFIG_SUPPORT_EMMC_RPMB 1671 Enable the commands for reading, writing and programming the 1672 key for the Replay Protection Memory Block partition in eMMC. 1673 1674- USB Device Firmware Update (DFU) class support: 1675 CONFIG_DFU_FUNCTION 1676 This enables the USB portion of the DFU USB class 1677 1678 CONFIG_CMD_DFU 1679 This enables the command "dfu" which is used to have 1680 U-Boot create a DFU class device via USB. This command 1681 requires that the "dfu_alt_info" environment variable be 1682 set and define the alt settings to expose to the host. 1683 1684 CONFIG_DFU_MMC 1685 This enables support for exposing (e)MMC devices via DFU. 1686 1687 CONFIG_DFU_NAND 1688 This enables support for exposing NAND devices via DFU. 1689 1690 CONFIG_DFU_RAM 1691 This enables support for exposing RAM via DFU. 1692 Note: DFU spec refer to non-volatile memory usage, but 1693 allow usages beyond the scope of spec - here RAM usage, 1694 one that would help mostly the developer. 1695 1696 CONFIG_SYS_DFU_DATA_BUF_SIZE 1697 Dfu transfer uses a buffer before writing data to the 1698 raw storage device. Make the size (in bytes) of this buffer 1699 configurable. The size of this buffer is also configurable 1700 through the "dfu_bufsiz" environment variable. 1701 1702 CONFIG_SYS_DFU_MAX_FILE_SIZE 1703 When updating files rather than the raw storage device, 1704 we use a static buffer to copy the file into and then write 1705 the buffer once we've been given the whole file. Define 1706 this to the maximum filesize (in bytes) for the buffer. 1707 Default is 4 MiB if undefined. 1708 1709 DFU_DEFAULT_POLL_TIMEOUT 1710 Poll timeout [ms], is the timeout a device can send to the 1711 host. The host must wait for this timeout before sending 1712 a subsequent DFU_GET_STATUS request to the device. 1713 1714 DFU_MANIFEST_POLL_TIMEOUT 1715 Poll timeout [ms], which the device sends to the host when 1716 entering dfuMANIFEST state. Host waits this timeout, before 1717 sending again an USB request to the device. 1718 1719- USB Device Android Fastboot support: 1720 CONFIG_CMD_FASTBOOT 1721 This enables the command "fastboot" which enables the Android 1722 fastboot mode for the platform's USB device. Fastboot is a USB 1723 protocol for downloading images, flashing and device control 1724 used on Android devices. 1725 See doc/README.android-fastboot for more information. 1726 1727 CONFIG_ANDROID_BOOT_IMAGE 1728 This enables support for booting images which use the Android 1729 image format header. 1730 1731 CONFIG_USB_FASTBOOT_BUF_ADDR 1732 The fastboot protocol requires a large memory buffer for 1733 downloads. Define this to the starting RAM address to use for 1734 downloaded images. 1735 1736 CONFIG_USB_FASTBOOT_BUF_SIZE 1737 The fastboot protocol requires a large memory buffer for 1738 downloads. This buffer should be as large as possible for a 1739 platform. Define this to the size available RAM for fastboot. 1740 1741 CONFIG_FASTBOOT_FLASH 1742 The fastboot protocol includes a "flash" command for writing 1743 the downloaded image to a non-volatile storage device. Define 1744 this to enable the "fastboot flash" command. 1745 1746 CONFIG_FASTBOOT_FLASH_MMC_DEV 1747 The fastboot "flash" command requires additional information 1748 regarding the non-volatile storage device. Define this to 1749 the eMMC device that fastboot should use to store the image. 1750 1751 CONFIG_FASTBOOT_GPT_NAME 1752 The fastboot "flash" command supports writing the downloaded 1753 image to the Protective MBR and the Primary GUID Partition 1754 Table. (Additionally, this downloaded image is post-processed 1755 to generate and write the Backup GUID Partition Table.) 1756 This occurs when the specified "partition name" on the 1757 "fastboot flash" command line matches this value. 1758 Default is GPT_ENTRY_NAME (currently "gpt") if undefined. 1759 1760- Journaling Flash filesystem support: 1761 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1762 CONFIG_JFFS2_NAND_DEV 1763 Define these for a default partition on a NAND device 1764 1765 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1766 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1767 Define these for a default partition on a NOR device 1768 1769 CONFIG_SYS_JFFS_CUSTOM_PART 1770 Define this to create an own partition. You have to provide a 1771 function struct part_info* jffs2_part_info(int part_num) 1772 1773 If you define only one JFFS2 partition you may also want to 1774 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1775 to disable the command chpart. This is the default when you 1776 have not defined a custom partition 1777 1778- FAT(File Allocation Table) filesystem write function support: 1779 CONFIG_FAT_WRITE 1780 1781 Define this to enable support for saving memory data as a 1782 file in FAT formatted partition. 1783 1784 This will also enable the command "fatwrite" enabling the 1785 user to write files to FAT. 1786 1787CBFS (Coreboot Filesystem) support 1788 CONFIG_CMD_CBFS 1789 1790 Define this to enable support for reading from a Coreboot 1791 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1792 and cbfsload. 1793 1794- FAT(File Allocation Table) filesystem cluster size: 1795 CONFIG_FS_FAT_MAX_CLUSTSIZE 1796 1797 Define the max cluster size for fat operations else 1798 a default value of 65536 will be defined. 1799 1800- Keyboard Support: 1801 CONFIG_ISA_KEYBOARD 1802 1803 Define this to enable standard (PC-Style) keyboard 1804 support 1805 1806 CONFIG_I8042_KBD 1807 Standard PC keyboard driver with US (is default) and 1808 GERMAN key layout (switch via environment 'keymap=de') support. 1809 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1810 for cfb_console. Supports cursor blinking. 1811 1812 CONFIG_CROS_EC_KEYB 1813 Enables a Chrome OS keyboard using the CROS_EC interface. 1814 This uses CROS_EC to communicate with a second microcontroller 1815 which provides key scans on request. 1816 1817- Video support: 1818 CONFIG_VIDEO 1819 1820 Define this to enable video support (for output to 1821 video). 1822 1823 CONFIG_VIDEO_CT69000 1824 1825 Enable Chips & Technologies 69000 Video chip 1826 1827 CONFIG_VIDEO_SMI_LYNXEM 1828 Enable Silicon Motion SMI 712/710/810 Video chip. The 1829 video output is selected via environment 'videoout' 1830 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1831 assumed. 1832 1833 For the CT69000 and SMI_LYNXEM drivers, videomode is 1834 selected via environment 'videomode'. Two different ways 1835 are possible: 1836 - "videomode=num" 'num' is a standard LiLo mode numbers. 1837 Following standard modes are supported (* is default): 1838 1839 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1840 -------------+--------------------------------------------- 1841 8 bits | 0x301* 0x303 0x305 0x161 0x307 1842 15 bits | 0x310 0x313 0x316 0x162 0x319 1843 16 bits | 0x311 0x314 0x317 0x163 0x31A 1844 24 bits | 0x312 0x315 0x318 ? 0x31B 1845 -------------+--------------------------------------------- 1846 (i.e. setenv videomode 317; saveenv; reset;) 1847 1848 - "videomode=bootargs" all the video parameters are parsed 1849 from the bootargs. (See drivers/video/videomodes.c) 1850 1851 1852 CONFIG_VIDEO_SED13806 1853 Enable Epson SED13806 driver. This driver supports 8bpp 1854 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1855 or CONFIG_VIDEO_SED13806_16BPP 1856 1857 CONFIG_FSL_DIU_FB 1858 Enable the Freescale DIU video driver. Reference boards for 1859 SOCs that have a DIU should define this macro to enable DIU 1860 support, and should also define these other macros: 1861 1862 CONFIG_SYS_DIU_ADDR 1863 CONFIG_VIDEO 1864 CONFIG_CMD_BMP 1865 CONFIG_CFB_CONSOLE 1866 CONFIG_VIDEO_SW_CURSOR 1867 CONFIG_VGA_AS_SINGLE_DEVICE 1868 CONFIG_VIDEO_LOGO 1869 CONFIG_VIDEO_BMP_LOGO 1870 1871 The DIU driver will look for the 'video-mode' environment 1872 variable, and if defined, enable the DIU as a console during 1873 boot. See the documentation file README.video for a 1874 description of this variable. 1875 1876 CONFIG_VIDEO_VGA 1877 1878 Enable the VGA video / BIOS for x86. The alternative if you 1879 are using coreboot is to use the coreboot frame buffer 1880 driver. 1881 1882 1883- Keyboard Support: 1884 CONFIG_KEYBOARD 1885 1886 Define this to enable a custom keyboard support. 1887 This simply calls drv_keyboard_init() which must be 1888 defined in your board-specific files. 1889 The only board using this so far is RBC823. 1890 1891- LCD Support: CONFIG_LCD 1892 1893 Define this to enable LCD support (for output to LCD 1894 display); also select one of the supported displays 1895 by defining one of these: 1896 1897 CONFIG_ATMEL_LCD: 1898 1899 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1900 1901 CONFIG_NEC_NL6448AC33: 1902 1903 NEC NL6448AC33-18. Active, color, single scan. 1904 1905 CONFIG_NEC_NL6448BC20 1906 1907 NEC NL6448BC20-08. 6.5", 640x480. 1908 Active, color, single scan. 1909 1910 CONFIG_NEC_NL6448BC33_54 1911 1912 NEC NL6448BC33-54. 10.4", 640x480. 1913 Active, color, single scan. 1914 1915 CONFIG_SHARP_16x9 1916 1917 Sharp 320x240. Active, color, single scan. 1918 It isn't 16x9, and I am not sure what it is. 1919 1920 CONFIG_SHARP_LQ64D341 1921 1922 Sharp LQ64D341 display, 640x480. 1923 Active, color, single scan. 1924 1925 CONFIG_HLD1045 1926 1927 HLD1045 display, 640x480. 1928 Active, color, single scan. 1929 1930 CONFIG_OPTREX_BW 1931 1932 Optrex CBL50840-2 NF-FW 99 22 M5 1933 or 1934 Hitachi LMG6912RPFC-00T 1935 or 1936 Hitachi SP14Q002 1937 1938 320x240. Black & white. 1939 1940 Normally display is black on white background; define 1941 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1942 1943 CONFIG_LCD_ALIGNMENT 1944 1945 Normally the LCD is page-aligned (typically 4KB). If this is 1946 defined then the LCD will be aligned to this value instead. 1947 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1948 here, since it is cheaper to change data cache settings on 1949 a per-section basis. 1950 1951 CONFIG_CONSOLE_SCROLL_LINES 1952 1953 When the console need to be scrolled, this is the number of 1954 lines to scroll by. It defaults to 1. Increasing this makes 1955 the console jump but can help speed up operation when scrolling 1956 is slow. 1957 1958 CONFIG_LCD_ROTATION 1959 1960 Sometimes, for example if the display is mounted in portrait 1961 mode or even if it's mounted landscape but rotated by 180degree, 1962 we need to rotate our content of the display relative to the 1963 framebuffer, so that user can read the messages which are 1964 printed out. 1965 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1966 initialized with a given rotation from "vl_rot" out of 1967 "vidinfo_t" which is provided by the board specific code. 1968 The value for vl_rot is coded as following (matching to 1969 fbcon=rotate:<n> linux-kernel commandline): 1970 0 = no rotation respectively 0 degree 1971 1 = 90 degree rotation 1972 2 = 180 degree rotation 1973 3 = 270 degree rotation 1974 1975 If CONFIG_LCD_ROTATION is not defined, the console will be 1976 initialized with 0degree rotation. 1977 1978 CONFIG_LCD_BMP_RLE8 1979 1980 Support drawing of RLE8-compressed bitmaps on the LCD. 1981 1982 CONFIG_I2C_EDID 1983 1984 Enables an 'i2c edid' command which can read EDID 1985 information over I2C from an attached LCD display. 1986 1987- Splash Screen Support: CONFIG_SPLASH_SCREEN 1988 1989 If this option is set, the environment is checked for 1990 a variable "splashimage". If found, the usual display 1991 of logo, copyright and system information on the LCD 1992 is suppressed and the BMP image at the address 1993 specified in "splashimage" is loaded instead. The 1994 console is redirected to the "nulldev", too. This 1995 allows for a "silent" boot where a splash screen is 1996 loaded very quickly after power-on. 1997 1998 CONFIG_SPLASHIMAGE_GUARD 1999 2000 If this option is set, then U-Boot will prevent the environment 2001 variable "splashimage" from being set to a problematic address 2002 (see README.displaying-bmps). 2003 This option is useful for targets where, due to alignment 2004 restrictions, an improperly aligned BMP image will cause a data 2005 abort. If you think you will not have problems with unaligned 2006 accesses (for example because your toolchain prevents them) 2007 there is no need to set this option. 2008 2009 CONFIG_SPLASH_SCREEN_ALIGN 2010 2011 If this option is set the splash image can be freely positioned 2012 on the screen. Environment variable "splashpos" specifies the 2013 position as "x,y". If a positive number is given it is used as 2014 number of pixel from left/top. If a negative number is given it 2015 is used as number of pixel from right/bottom. You can also 2016 specify 'm' for centering the image. 2017 2018 Example: 2019 setenv splashpos m,m 2020 => image at center of screen 2021 2022 setenv splashpos 30,20 2023 => image at x = 30 and y = 20 2024 2025 setenv splashpos -10,m 2026 => vertically centered image 2027 at x = dspWidth - bmpWidth - 9 2028 2029- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 2030 2031 If this option is set, additionally to standard BMP 2032 images, gzipped BMP images can be displayed via the 2033 splashscreen support or the bmp command. 2034 2035- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 2036 2037 If this option is set, 8-bit RLE compressed BMP images 2038 can be displayed via the splashscreen support or the 2039 bmp command. 2040 2041- Do compressing for memory range: 2042 CONFIG_CMD_ZIP 2043 2044 If this option is set, it would use zlib deflate method 2045 to compress the specified memory at its best effort. 2046 2047- Compression support: 2048 CONFIG_GZIP 2049 2050 Enabled by default to support gzip compressed images. 2051 2052 CONFIG_BZIP2 2053 2054 If this option is set, support for bzip2 compressed 2055 images is included. If not, only uncompressed and gzip 2056 compressed images are supported. 2057 2058 NOTE: the bzip2 algorithm requires a lot of RAM, so 2059 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 2060 be at least 4MB. 2061 2062 CONFIG_LZMA 2063 2064 If this option is set, support for lzma compressed 2065 images is included. 2066 2067 Note: The LZMA algorithm adds between 2 and 4KB of code and it 2068 requires an amount of dynamic memory that is given by the 2069 formula: 2070 2071 (1846 + 768 << (lc + lp)) * sizeof(uint16) 2072 2073 Where lc and lp stand for, respectively, Literal context bits 2074 and Literal pos bits. 2075 2076 This value is upper-bounded by 14MB in the worst case. Anyway, 2077 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 2078 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 2079 a very small buffer. 2080 2081 Use the lzmainfo tool to determinate the lc and lp values and 2082 then calculate the amount of needed dynamic memory (ensuring 2083 the appropriate CONFIG_SYS_MALLOC_LEN value). 2084 2085 CONFIG_LZO 2086 2087 If this option is set, support for LZO compressed images 2088 is included. 2089 2090- MII/PHY support: 2091 CONFIG_PHY_ADDR 2092 2093 The address of PHY on MII bus. 2094 2095 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 2096 2097 The clock frequency of the MII bus 2098 2099 CONFIG_PHY_GIGE 2100 2101 If this option is set, support for speed/duplex 2102 detection of gigabit PHY is included. 2103 2104 CONFIG_PHY_RESET_DELAY 2105 2106 Some PHY like Intel LXT971A need extra delay after 2107 reset before any MII register access is possible. 2108 For such PHY, set this option to the usec delay 2109 required. (minimum 300usec for LXT971A) 2110 2111 CONFIG_PHY_CMD_DELAY (ppc4xx) 2112 2113 Some PHY like Intel LXT971A need extra delay after 2114 command issued before MII status register can be read 2115 2116- Ethernet address: 2117 CONFIG_ETHADDR 2118 CONFIG_ETH1ADDR 2119 CONFIG_ETH2ADDR 2120 CONFIG_ETH3ADDR 2121 CONFIG_ETH4ADDR 2122 CONFIG_ETH5ADDR 2123 2124 Define a default value for Ethernet address to use 2125 for the respective Ethernet interface, in case this 2126 is not determined automatically. 2127 2128- IP address: 2129 CONFIG_IPADDR 2130 2131 Define a default value for the IP address to use for 2132 the default Ethernet interface, in case this is not 2133 determined through e.g. bootp. 2134 (Environment variable "ipaddr") 2135 2136- Server IP address: 2137 CONFIG_SERVERIP 2138 2139 Defines a default value for the IP address of a TFTP 2140 server to contact when using the "tftboot" command. 2141 (Environment variable "serverip") 2142 2143 CONFIG_KEEP_SERVERADDR 2144 2145 Keeps the server's MAC address, in the env 'serveraddr' 2146 for passing to bootargs (like Linux's netconsole option) 2147 2148- Gateway IP address: 2149 CONFIG_GATEWAYIP 2150 2151 Defines a default value for the IP address of the 2152 default router where packets to other networks are 2153 sent to. 2154 (Environment variable "gatewayip") 2155 2156- Subnet mask: 2157 CONFIG_NETMASK 2158 2159 Defines a default value for the subnet mask (or 2160 routing prefix) which is used to determine if an IP 2161 address belongs to the local subnet or needs to be 2162 forwarded through a router. 2163 (Environment variable "netmask") 2164 2165- Multicast TFTP Mode: 2166 CONFIG_MCAST_TFTP 2167 2168 Defines whether you want to support multicast TFTP as per 2169 rfc-2090; for example to work with atftp. Lets lots of targets 2170 tftp down the same boot image concurrently. Note: the Ethernet 2171 driver in use must provide a function: mcast() to join/leave a 2172 multicast group. 2173 2174- BOOTP Recovery Mode: 2175 CONFIG_BOOTP_RANDOM_DELAY 2176 2177 If you have many targets in a network that try to 2178 boot using BOOTP, you may want to avoid that all 2179 systems send out BOOTP requests at precisely the same 2180 moment (which would happen for instance at recovery 2181 from a power failure, when all systems will try to 2182 boot, thus flooding the BOOTP server. Defining 2183 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 2184 inserted before sending out BOOTP requests. The 2185 following delays are inserted then: 2186 2187 1st BOOTP request: delay 0 ... 1 sec 2188 2nd BOOTP request: delay 0 ... 2 sec 2189 3rd BOOTP request: delay 0 ... 4 sec 2190 4th and following 2191 BOOTP requests: delay 0 ... 8 sec 2192 2193 CONFIG_BOOTP_ID_CACHE_SIZE 2194 2195 BOOTP packets are uniquely identified using a 32-bit ID. The 2196 server will copy the ID from client requests to responses and 2197 U-Boot will use this to determine if it is the destination of 2198 an incoming response. Some servers will check that addresses 2199 aren't in use before handing them out (usually using an ARP 2200 ping) and therefore take up to a few hundred milliseconds to 2201 respond. Network congestion may also influence the time it 2202 takes for a response to make it back to the client. If that 2203 time is too long, U-Boot will retransmit requests. In order 2204 to allow earlier responses to still be accepted after these 2205 retransmissions, U-Boot's BOOTP client keeps a small cache of 2206 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 2207 cache. The default is to keep IDs for up to four outstanding 2208 requests. Increasing this will allow U-Boot to accept offers 2209 from a BOOTP client in networks with unusually high latency. 2210 2211- DHCP Advanced Options: 2212 You can fine tune the DHCP functionality by defining 2213 CONFIG_BOOTP_* symbols: 2214 2215 CONFIG_BOOTP_SUBNETMASK 2216 CONFIG_BOOTP_GATEWAY 2217 CONFIG_BOOTP_HOSTNAME 2218 CONFIG_BOOTP_NISDOMAIN 2219 CONFIG_BOOTP_BOOTPATH 2220 CONFIG_BOOTP_BOOTFILESIZE 2221 CONFIG_BOOTP_DNS 2222 CONFIG_BOOTP_DNS2 2223 CONFIG_BOOTP_SEND_HOSTNAME 2224 CONFIG_BOOTP_NTPSERVER 2225 CONFIG_BOOTP_TIMEOFFSET 2226 CONFIG_BOOTP_VENDOREX 2227 CONFIG_BOOTP_MAY_FAIL 2228 2229 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2230 environment variable, not the BOOTP server. 2231 2232 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2233 after the configured retry count, the call will fail 2234 instead of starting over. This can be used to fail over 2235 to Link-local IP address configuration if the DHCP server 2236 is not available. 2237 2238 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2239 serverip from a DHCP server, it is possible that more 2240 than one DNS serverip is offered to the client. 2241 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2242 serverip will be stored in the additional environment 2243 variable "dnsip2". The first DNS serverip is always 2244 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2245 is defined. 2246 2247 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2248 to do a dynamic update of a DNS server. To do this, they 2249 need the hostname of the DHCP requester. 2250 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2251 of the "hostname" environment variable is passed as 2252 option 12 to the DHCP server. 2253 2254 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2255 2256 A 32bit value in microseconds for a delay between 2257 receiving a "DHCP Offer" and sending the "DHCP Request". 2258 This fixes a problem with certain DHCP servers that don't 2259 respond 100% of the time to a "DHCP request". E.g. On an 2260 AT91RM9200 processor running at 180MHz, this delay needed 2261 to be *at least* 15,000 usec before a Windows Server 2003 2262 DHCP server would reply 100% of the time. I recommend at 2263 least 50,000 usec to be safe. The alternative is to hope 2264 that one of the retries will be successful but note that 2265 the DHCP timeout and retry process takes a longer than 2266 this delay. 2267 2268 - Link-local IP address negotiation: 2269 Negotiate with other link-local clients on the local network 2270 for an address that doesn't require explicit configuration. 2271 This is especially useful if a DHCP server cannot be guaranteed 2272 to exist in all environments that the device must operate. 2273 2274 See doc/README.link-local for more information. 2275 2276 - CDP Options: 2277 CONFIG_CDP_DEVICE_ID 2278 2279 The device id used in CDP trigger frames. 2280 2281 CONFIG_CDP_DEVICE_ID_PREFIX 2282 2283 A two character string which is prefixed to the MAC address 2284 of the device. 2285 2286 CONFIG_CDP_PORT_ID 2287 2288 A printf format string which contains the ascii name of 2289 the port. Normally is set to "eth%d" which sets 2290 eth0 for the first Ethernet, eth1 for the second etc. 2291 2292 CONFIG_CDP_CAPABILITIES 2293 2294 A 32bit integer which indicates the device capabilities; 2295 0x00000010 for a normal host which does not forwards. 2296 2297 CONFIG_CDP_VERSION 2298 2299 An ascii string containing the version of the software. 2300 2301 CONFIG_CDP_PLATFORM 2302 2303 An ascii string containing the name of the platform. 2304 2305 CONFIG_CDP_TRIGGER 2306 2307 A 32bit integer sent on the trigger. 2308 2309 CONFIG_CDP_POWER_CONSUMPTION 2310 2311 A 16bit integer containing the power consumption of the 2312 device in .1 of milliwatts. 2313 2314 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2315 2316 A byte containing the id of the VLAN. 2317 2318- Status LED: CONFIG_STATUS_LED 2319 2320 Several configurations allow to display the current 2321 status using a LED. For instance, the LED will blink 2322 fast while running U-Boot code, stop blinking as 2323 soon as a reply to a BOOTP request was received, and 2324 start blinking slow once the Linux kernel is running 2325 (supported by a status LED driver in the Linux 2326 kernel). Defining CONFIG_STATUS_LED enables this 2327 feature in U-Boot. 2328 2329 Additional options: 2330 2331 CONFIG_GPIO_LED 2332 The status LED can be connected to a GPIO pin. 2333 In such cases, the gpio_led driver can be used as a 2334 status LED backend implementation. Define CONFIG_GPIO_LED 2335 to include the gpio_led driver in the U-Boot binary. 2336 2337 CONFIG_GPIO_LED_INVERTED_TABLE 2338 Some GPIO connected LEDs may have inverted polarity in which 2339 case the GPIO high value corresponds to LED off state and 2340 GPIO low value corresponds to LED on state. 2341 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2342 with a list of GPIO LEDs that have inverted polarity. 2343 2344- CAN Support: CONFIG_CAN_DRIVER 2345 2346 Defining CONFIG_CAN_DRIVER enables CAN driver support 2347 on those systems that support this (optional) 2348 feature, like the TQM8xxL modules. 2349 2350- I2C Support: CONFIG_SYS_I2C 2351 2352 This enable the NEW i2c subsystem, and will allow you to use 2353 i2c commands at the u-boot command line (as long as you set 2354 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2355 based realtime clock chips or other i2c devices. See 2356 common/cmd_i2c.c for a description of the command line 2357 interface. 2358 2359 ported i2c driver to the new framework: 2360 - drivers/i2c/soft_i2c.c: 2361 - activate first bus with CONFIG_SYS_I2C_SOFT define 2362 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2363 for defining speed and slave address 2364 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2365 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2366 for defining speed and slave address 2367 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2368 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2369 for defining speed and slave address 2370 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2371 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2372 for defining speed and slave address 2373 2374 - drivers/i2c/fsl_i2c.c: 2375 - activate i2c driver with CONFIG_SYS_I2C_FSL 2376 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2377 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2378 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2379 bus. 2380 - If your board supports a second fsl i2c bus, define 2381 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2382 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2383 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2384 second bus. 2385 2386 - drivers/i2c/tegra_i2c.c: 2387 - activate this driver with CONFIG_SYS_I2C_TEGRA 2388 - This driver adds 4 i2c buses with a fix speed from 2389 100000 and the slave addr 0! 2390 2391 - drivers/i2c/ppc4xx_i2c.c 2392 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2393 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2394 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2395 2396 - drivers/i2c/i2c_mxc.c 2397 - activate this driver with CONFIG_SYS_I2C_MXC 2398 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2399 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2400 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2401 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2402 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2403 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2404 If those defines are not set, default value is 100000 2405 for speed, and 0 for slave. 2406 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2407 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2408 2409 - drivers/i2c/rcar_i2c.c: 2410 - activate this driver with CONFIG_SYS_I2C_RCAR 2411 - This driver adds 4 i2c buses 2412 2413 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2414 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2415 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2416 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2417 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2418 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2419 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2420 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2421 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2422 2423 - drivers/i2c/sh_i2c.c: 2424 - activate this driver with CONFIG_SYS_I2C_SH 2425 - This driver adds from 2 to 5 i2c buses 2426 2427 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2428 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2429 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2430 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2431 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2432 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2433 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2434 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2435 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2436 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2437 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2438 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2439 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2440 2441 - drivers/i2c/omap24xx_i2c.c 2442 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2443 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2444 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2445 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2446 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2447 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2448 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2449 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2450 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2451 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2452 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2453 2454 - drivers/i2c/zynq_i2c.c 2455 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2456 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2457 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2458 2459 - drivers/i2c/s3c24x0_i2c.c: 2460 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2461 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2462 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2463 with a fix speed from 100000 and the slave addr 0! 2464 2465 - drivers/i2c/ihs_i2c.c 2466 - activate this driver with CONFIG_SYS_I2C_IHS 2467 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2468 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2469 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2470 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2471 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2472 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2473 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2474 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2475 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2476 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2477 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2478 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2479 2480 additional defines: 2481 2482 CONFIG_SYS_NUM_I2C_BUSES 2483 Hold the number of i2c buses you want to use. If you 2484 don't use/have i2c muxes on your i2c bus, this 2485 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2486 omit this define. 2487 2488 CONFIG_SYS_I2C_DIRECT_BUS 2489 define this, if you don't use i2c muxes on your hardware. 2490 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2491 omit this define. 2492 2493 CONFIG_SYS_I2C_MAX_HOPS 2494 define how many muxes are maximal consecutively connected 2495 on one i2c bus. If you not use i2c muxes, omit this 2496 define. 2497 2498 CONFIG_SYS_I2C_BUSES 2499 hold a list of buses you want to use, only used if 2500 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2501 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2502 CONFIG_SYS_NUM_I2C_BUSES = 9: 2503 2504 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2505 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2506 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2507 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2508 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2509 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2510 {1, {I2C_NULL_HOP}}, \ 2511 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2512 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2513 } 2514 2515 which defines 2516 bus 0 on adapter 0 without a mux 2517 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2518 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2519 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2520 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2521 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2522 bus 6 on adapter 1 without a mux 2523 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2524 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2525 2526 If you do not have i2c muxes on your board, omit this define. 2527 2528- Legacy I2C Support: CONFIG_HARD_I2C 2529 2530 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2531 provides the following compelling advantages: 2532 2533 - more than one i2c adapter is usable 2534 - approved multibus support 2535 - better i2c mux support 2536 2537 ** Please consider updating your I2C driver now. ** 2538 2539 These enable legacy I2C serial bus commands. Defining 2540 CONFIG_HARD_I2C will include the appropriate I2C driver 2541 for the selected CPU. 2542 2543 This will allow you to use i2c commands at the u-boot 2544 command line (as long as you set CONFIG_CMD_I2C in 2545 CONFIG_COMMANDS) and communicate with i2c based realtime 2546 clock chips. See common/cmd_i2c.c for a description of the 2547 command line interface. 2548 2549 CONFIG_HARD_I2C selects a hardware I2C controller. 2550 2551 There are several other quantities that must also be 2552 defined when you define CONFIG_HARD_I2C. 2553 2554 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2555 to be the frequency (in Hz) at which you wish your i2c bus 2556 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2557 the CPU's i2c node address). 2558 2559 Now, the u-boot i2c code for the mpc8xx 2560 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2561 and so its address should therefore be cleared to 0 (See, 2562 eg, MPC823e User's Manual p.16-473). So, set 2563 CONFIG_SYS_I2C_SLAVE to 0. 2564 2565 CONFIG_SYS_I2C_INIT_MPC5XXX 2566 2567 When a board is reset during an i2c bus transfer 2568 chips might think that the current transfer is still 2569 in progress. Reset the slave devices by sending start 2570 commands until the slave device responds. 2571 2572 That's all that's required for CONFIG_HARD_I2C. 2573 2574 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2575 then the following macros need to be defined (examples are 2576 from include/configs/lwmon.h): 2577 2578 I2C_INIT 2579 2580 (Optional). Any commands necessary to enable the I2C 2581 controller or configure ports. 2582 2583 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2584 2585 I2C_PORT 2586 2587 (Only for MPC8260 CPU). The I/O port to use (the code 2588 assumes both bits are on the same port). Valid values 2589 are 0..3 for ports A..D. 2590 2591 I2C_ACTIVE 2592 2593 The code necessary to make the I2C data line active 2594 (driven). If the data line is open collector, this 2595 define can be null. 2596 2597 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2598 2599 I2C_TRISTATE 2600 2601 The code necessary to make the I2C data line tri-stated 2602 (inactive). If the data line is open collector, this 2603 define can be null. 2604 2605 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2606 2607 I2C_READ 2608 2609 Code that returns true if the I2C data line is high, 2610 false if it is low. 2611 2612 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2613 2614 I2C_SDA(bit) 2615 2616 If <bit> is true, sets the I2C data line high. If it 2617 is false, it clears it (low). 2618 2619 eg: #define I2C_SDA(bit) \ 2620 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2621 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2622 2623 I2C_SCL(bit) 2624 2625 If <bit> is true, sets the I2C clock line high. If it 2626 is false, it clears it (low). 2627 2628 eg: #define I2C_SCL(bit) \ 2629 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2630 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2631 2632 I2C_DELAY 2633 2634 This delay is invoked four times per clock cycle so this 2635 controls the rate of data transfer. The data rate thus 2636 is 1 / (I2C_DELAY * 4). Often defined to be something 2637 like: 2638 2639 #define I2C_DELAY udelay(2) 2640 2641 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2642 2643 If your arch supports the generic GPIO framework (asm/gpio.h), 2644 then you may alternatively define the two GPIOs that are to be 2645 used as SCL / SDA. Any of the previous I2C_xxx macros will 2646 have GPIO-based defaults assigned to them as appropriate. 2647 2648 You should define these to the GPIO value as given directly to 2649 the generic GPIO functions. 2650 2651 CONFIG_SYS_I2C_INIT_BOARD 2652 2653 When a board is reset during an i2c bus transfer 2654 chips might think that the current transfer is still 2655 in progress. On some boards it is possible to access 2656 the i2c SCLK line directly, either by using the 2657 processor pin as a GPIO or by having a second pin 2658 connected to the bus. If this option is defined a 2659 custom i2c_init_board() routine in boards/xxx/board.c 2660 is run early in the boot sequence. 2661 2662 CONFIG_SYS_I2C_BOARD_LATE_INIT 2663 2664 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2665 defined a custom i2c_board_late_init() routine in 2666 boards/xxx/board.c is run AFTER the operations in i2c_init() 2667 is completed. This callpoint can be used to unreset i2c bus 2668 using CPU i2c controller register accesses for CPUs whose i2c 2669 controller provide such a method. It is called at the end of 2670 i2c_init() to allow i2c_init operations to setup the i2c bus 2671 controller on the CPU (e.g. setting bus speed & slave address). 2672 2673 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2674 2675 This option enables configuration of bi_iic_fast[] flags 2676 in u-boot bd_info structure based on u-boot environment 2677 variable "i2cfast". (see also i2cfast) 2678 2679 CONFIG_I2C_MULTI_BUS 2680 2681 This option allows the use of multiple I2C buses, each of which 2682 must have a controller. At any point in time, only one bus is 2683 active. To switch to a different bus, use the 'i2c dev' command. 2684 Note that bus numbering is zero-based. 2685 2686 CONFIG_SYS_I2C_NOPROBES 2687 2688 This option specifies a list of I2C devices that will be skipped 2689 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2690 is set, specify a list of bus-device pairs. Otherwise, specify 2691 a 1D array of device addresses 2692 2693 e.g. 2694 #undef CONFIG_I2C_MULTI_BUS 2695 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2696 2697 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2698 2699 #define CONFIG_I2C_MULTI_BUS 2700 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2701 2702 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2703 2704 CONFIG_SYS_SPD_BUS_NUM 2705 2706 If defined, then this indicates the I2C bus number for DDR SPD. 2707 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2708 2709 CONFIG_SYS_RTC_BUS_NUM 2710 2711 If defined, then this indicates the I2C bus number for the RTC. 2712 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2713 2714 CONFIG_SYS_DTT_BUS_NUM 2715 2716 If defined, then this indicates the I2C bus number for the DTT. 2717 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2718 2719 CONFIG_SYS_I2C_DTT_ADDR: 2720 2721 If defined, specifies the I2C address of the DTT device. 2722 If not defined, then U-Boot uses predefined value for 2723 specified DTT device. 2724 2725 CONFIG_SOFT_I2C_READ_REPEATED_START 2726 2727 defining this will force the i2c_read() function in 2728 the soft_i2c driver to perform an I2C repeated start 2729 between writing the address pointer and reading the 2730 data. If this define is omitted the default behaviour 2731 of doing a stop-start sequence will be used. Most I2C 2732 devices can use either method, but some require one or 2733 the other. 2734 2735- SPI Support: CONFIG_SPI 2736 2737 Enables SPI driver (so far only tested with 2738 SPI EEPROM, also an instance works with Crystal A/D and 2739 D/As on the SACSng board) 2740 2741 CONFIG_SH_SPI 2742 2743 Enables the driver for SPI controller on SuperH. Currently 2744 only SH7757 is supported. 2745 2746 CONFIG_SPI_X 2747 2748 Enables extended (16-bit) SPI EEPROM addressing. 2749 (symmetrical to CONFIG_I2C_X) 2750 2751 CONFIG_SOFT_SPI 2752 2753 Enables a software (bit-bang) SPI driver rather than 2754 using hardware support. This is a general purpose 2755 driver that only requires three general I/O port pins 2756 (two outputs, one input) to function. If this is 2757 defined, the board configuration must define several 2758 SPI configuration items (port pins to use, etc). For 2759 an example, see include/configs/sacsng.h. 2760 2761 CONFIG_HARD_SPI 2762 2763 Enables a hardware SPI driver for general-purpose reads 2764 and writes. As with CONFIG_SOFT_SPI, the board configuration 2765 must define a list of chip-select function pointers. 2766 Currently supported on some MPC8xxx processors. For an 2767 example, see include/configs/mpc8349emds.h. 2768 2769 CONFIG_MXC_SPI 2770 2771 Enables the driver for the SPI controllers on i.MX and MXC 2772 SoCs. Currently i.MX31/35/51 are supported. 2773 2774 CONFIG_SYS_SPI_MXC_WAIT 2775 Timeout for waiting until spi transfer completed. 2776 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2777 2778- FPGA Support: CONFIG_FPGA 2779 2780 Enables FPGA subsystem. 2781 2782 CONFIG_FPGA_<vendor> 2783 2784 Enables support for specific chip vendors. 2785 (ALTERA, XILINX) 2786 2787 CONFIG_FPGA_<family> 2788 2789 Enables support for FPGA family. 2790 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2791 2792 CONFIG_FPGA_COUNT 2793 2794 Specify the number of FPGA devices to support. 2795 2796 CONFIG_CMD_FPGA_LOADMK 2797 2798 Enable support for fpga loadmk command 2799 2800 CONFIG_CMD_FPGA_LOADP 2801 2802 Enable support for fpga loadp command - load partial bitstream 2803 2804 CONFIG_CMD_FPGA_LOADBP 2805 2806 Enable support for fpga loadbp command - load partial bitstream 2807 (Xilinx only) 2808 2809 CONFIG_SYS_FPGA_PROG_FEEDBACK 2810 2811 Enable printing of hash marks during FPGA configuration. 2812 2813 CONFIG_SYS_FPGA_CHECK_BUSY 2814 2815 Enable checks on FPGA configuration interface busy 2816 status by the configuration function. This option 2817 will require a board or device specific function to 2818 be written. 2819 2820 CONFIG_FPGA_DELAY 2821 2822 If defined, a function that provides delays in the FPGA 2823 configuration driver. 2824 2825 CONFIG_SYS_FPGA_CHECK_CTRLC 2826 Allow Control-C to interrupt FPGA configuration 2827 2828 CONFIG_SYS_FPGA_CHECK_ERROR 2829 2830 Check for configuration errors during FPGA bitfile 2831 loading. For example, abort during Virtex II 2832 configuration if the INIT_B line goes low (which 2833 indicated a CRC error). 2834 2835 CONFIG_SYS_FPGA_WAIT_INIT 2836 2837 Maximum time to wait for the INIT_B line to de-assert 2838 after PROB_B has been de-asserted during a Virtex II 2839 FPGA configuration sequence. The default time is 500 2840 ms. 2841 2842 CONFIG_SYS_FPGA_WAIT_BUSY 2843 2844 Maximum time to wait for BUSY to de-assert during 2845 Virtex II FPGA configuration. The default is 5 ms. 2846 2847 CONFIG_SYS_FPGA_WAIT_CONFIG 2848 2849 Time to wait after FPGA configuration. The default is 2850 200 ms. 2851 2852- Configuration Management: 2853 CONFIG_BUILD_TARGET 2854 2855 Some SoCs need special image types (e.g. U-Boot binary 2856 with a special header) as build targets. By defining 2857 CONFIG_BUILD_TARGET in the SoC / board header, this 2858 special image will be automatically built upon calling 2859 make / MAKEALL. 2860 2861 CONFIG_IDENT_STRING 2862 2863 If defined, this string will be added to the U-Boot 2864 version information (U_BOOT_VERSION) 2865 2866- Vendor Parameter Protection: 2867 2868 U-Boot considers the values of the environment 2869 variables "serial#" (Board Serial Number) and 2870 "ethaddr" (Ethernet Address) to be parameters that 2871 are set once by the board vendor / manufacturer, and 2872 protects these variables from casual modification by 2873 the user. Once set, these variables are read-only, 2874 and write or delete attempts are rejected. You can 2875 change this behaviour: 2876 2877 If CONFIG_ENV_OVERWRITE is #defined in your config 2878 file, the write protection for vendor parameters is 2879 completely disabled. Anybody can change or delete 2880 these parameters. 2881 2882 Alternatively, if you #define _both_ CONFIG_ETHADDR 2883 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2884 Ethernet address is installed in the environment, 2885 which can be changed exactly ONCE by the user. [The 2886 serial# is unaffected by this, i. e. it remains 2887 read-only.] 2888 2889 The same can be accomplished in a more flexible way 2890 for any variable by configuring the type of access 2891 to allow for those variables in the ".flags" variable 2892 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2893 2894- Protected RAM: 2895 CONFIG_PRAM 2896 2897 Define this variable to enable the reservation of 2898 "protected RAM", i. e. RAM which is not overwritten 2899 by U-Boot. Define CONFIG_PRAM to hold the number of 2900 kB you want to reserve for pRAM. You can overwrite 2901 this default value by defining an environment 2902 variable "pram" to the number of kB you want to 2903 reserve. Note that the board info structure will 2904 still show the full amount of RAM. If pRAM is 2905 reserved, a new environment variable "mem" will 2906 automatically be defined to hold the amount of 2907 remaining RAM in a form that can be passed as boot 2908 argument to Linux, for instance like that: 2909 2910 setenv bootargs ... mem=\${mem} 2911 saveenv 2912 2913 This way you can tell Linux not to use this memory, 2914 either, which results in a memory region that will 2915 not be affected by reboots. 2916 2917 *WARNING* If your board configuration uses automatic 2918 detection of the RAM size, you must make sure that 2919 this memory test is non-destructive. So far, the 2920 following board configurations are known to be 2921 "pRAM-clean": 2922 2923 IVMS8, IVML24, SPD8xx, TQM8xxL, 2924 HERMES, IP860, RPXlite, LWMON, 2925 FLAGADM, TQM8260 2926 2927- Access to physical memory region (> 4GB) 2928 Some basic support is provided for operations on memory not 2929 normally accessible to U-Boot - e.g. some architectures 2930 support access to more than 4GB of memory on 32-bit 2931 machines using physical address extension or similar. 2932 Define CONFIG_PHYSMEM to access this basic support, which 2933 currently only supports clearing the memory. 2934 2935- Error Recovery: 2936 CONFIG_PANIC_HANG 2937 2938 Define this variable to stop the system in case of a 2939 fatal error, so that you have to reset it manually. 2940 This is probably NOT a good idea for an embedded 2941 system where you want the system to reboot 2942 automatically as fast as possible, but it may be 2943 useful during development since you can try to debug 2944 the conditions that lead to the situation. 2945 2946 CONFIG_NET_RETRY_COUNT 2947 2948 This variable defines the number of retries for 2949 network operations like ARP, RARP, TFTP, or BOOTP 2950 before giving up the operation. If not defined, a 2951 default value of 5 is used. 2952 2953 CONFIG_ARP_TIMEOUT 2954 2955 Timeout waiting for an ARP reply in milliseconds. 2956 2957 CONFIG_NFS_TIMEOUT 2958 2959 Timeout in milliseconds used in NFS protocol. 2960 If you encounter "ERROR: Cannot umount" in nfs command, 2961 try longer timeout such as 2962 #define CONFIG_NFS_TIMEOUT 10000UL 2963 2964- Command Interpreter: 2965 CONFIG_AUTO_COMPLETE 2966 2967 Enable auto completion of commands using TAB. 2968 2969 CONFIG_SYS_PROMPT_HUSH_PS2 2970 2971 This defines the secondary prompt string, which is 2972 printed when the command interpreter needs more input 2973 to complete a command. Usually "> ". 2974 2975 Note: 2976 2977 In the current implementation, the local variables 2978 space and global environment variables space are 2979 separated. Local variables are those you define by 2980 simply typing `name=value'. To access a local 2981 variable later on, you have write `$name' or 2982 `${name}'; to execute the contents of a variable 2983 directly type `$name' at the command prompt. 2984 2985 Global environment variables are those you use 2986 setenv/printenv to work with. To run a command stored 2987 in such a variable, you need to use the run command, 2988 and you must not use the '$' sign to access them. 2989 2990 To store commands and special characters in a 2991 variable, please use double quotation marks 2992 surrounding the whole text of the variable, instead 2993 of the backslashes before semicolons and special 2994 symbols. 2995 2996- Command Line Editing and History: 2997 CONFIG_CMDLINE_EDITING 2998 2999 Enable editing and History functions for interactive 3000 command line input operations 3001 3002- Default Environment: 3003 CONFIG_EXTRA_ENV_SETTINGS 3004 3005 Define this to contain any number of null terminated 3006 strings (variable = value pairs) that will be part of 3007 the default environment compiled into the boot image. 3008 3009 For example, place something like this in your 3010 board's config file: 3011 3012 #define CONFIG_EXTRA_ENV_SETTINGS \ 3013 "myvar1=value1\0" \ 3014 "myvar2=value2\0" 3015 3016 Warning: This method is based on knowledge about the 3017 internal format how the environment is stored by the 3018 U-Boot code. This is NOT an official, exported 3019 interface! Although it is unlikely that this format 3020 will change soon, there is no guarantee either. 3021 You better know what you are doing here. 3022 3023 Note: overly (ab)use of the default environment is 3024 discouraged. Make sure to check other ways to preset 3025 the environment like the "source" command or the 3026 boot command first. 3027 3028 CONFIG_ENV_VARS_UBOOT_CONFIG 3029 3030 Define this in order to add variables describing the 3031 U-Boot build configuration to the default environment. 3032 These will be named arch, cpu, board, vendor, and soc. 3033 3034 Enabling this option will cause the following to be defined: 3035 3036 - CONFIG_SYS_ARCH 3037 - CONFIG_SYS_CPU 3038 - CONFIG_SYS_BOARD 3039 - CONFIG_SYS_VENDOR 3040 - CONFIG_SYS_SOC 3041 3042 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 3043 3044 Define this in order to add variables describing certain 3045 run-time determined information about the hardware to the 3046 environment. These will be named board_name, board_rev. 3047 3048 CONFIG_DELAY_ENVIRONMENT 3049 3050 Normally the environment is loaded when the board is 3051 initialised so that it is available to U-Boot. This inhibits 3052 that so that the environment is not available until 3053 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 3054 this is instead controlled by the value of 3055 /config/load-environment. 3056 3057- DataFlash Support: 3058 CONFIG_HAS_DATAFLASH 3059 3060 Defining this option enables DataFlash features and 3061 allows to read/write in Dataflash via the standard 3062 commands cp, md... 3063 3064- Serial Flash support 3065 CONFIG_CMD_SF 3066 3067 Defining this option enables SPI flash commands 3068 'sf probe/read/write/erase/update'. 3069 3070 Usage requires an initial 'probe' to define the serial 3071 flash parameters, followed by read/write/erase/update 3072 commands. 3073 3074 The following defaults may be provided by the platform 3075 to handle the common case when only a single serial 3076 flash is present on the system. 3077 3078 CONFIG_SF_DEFAULT_BUS Bus identifier 3079 CONFIG_SF_DEFAULT_CS Chip-select 3080 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 3081 CONFIG_SF_DEFAULT_SPEED in Hz 3082 3083 CONFIG_CMD_SF_TEST 3084 3085 Define this option to include a destructive SPI flash 3086 test ('sf test'). 3087 3088 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg 3089 3090 Define this option to use the Bank addr/Extended addr 3091 support on SPI flashes which has size > 16Mbytes. 3092 3093 CONFIG_SF_DUAL_FLASH Dual flash memories 3094 3095 Define this option to use dual flash support where two flash 3096 memories can be connected with a given cs line. 3097 Currently Xilinx Zynq qspi supports these type of connections. 3098 3099 CONFIG_SYS_SPI_ST_ENABLE_WP_PIN 3100 enable the W#/Vpp signal to disable writing to the status 3101 register on ST MICRON flashes like the N25Q128. 3102 The status register write enable/disable bit, combined with 3103 the W#/VPP signal provides hardware data protection for the 3104 device as follows: When the enable/disable bit is set to 1, 3105 and the W#/VPP signal is driven LOW, the status register 3106 nonvolatile bits become read-only and the WRITE STATUS REGISTER 3107 operation will not execute. The only way to exit this 3108 hardware-protected mode is to drive W#/VPP HIGH. 3109 3110- SystemACE Support: 3111 CONFIG_SYSTEMACE 3112 3113 Adding this option adds support for Xilinx SystemACE 3114 chips attached via some sort of local bus. The address 3115 of the chip must also be defined in the 3116 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 3117 3118 #define CONFIG_SYSTEMACE 3119 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 3120 3121 When SystemACE support is added, the "ace" device type 3122 becomes available to the fat commands, i.e. fatls. 3123 3124- TFTP Fixed UDP Port: 3125 CONFIG_TFTP_PORT 3126 3127 If this is defined, the environment variable tftpsrcp 3128 is used to supply the TFTP UDP source port value. 3129 If tftpsrcp isn't defined, the normal pseudo-random port 3130 number generator is used. 3131 3132 Also, the environment variable tftpdstp is used to supply 3133 the TFTP UDP destination port value. If tftpdstp isn't 3134 defined, the normal port 69 is used. 3135 3136 The purpose for tftpsrcp is to allow a TFTP server to 3137 blindly start the TFTP transfer using the pre-configured 3138 target IP address and UDP port. This has the effect of 3139 "punching through" the (Windows XP) firewall, allowing 3140 the remainder of the TFTP transfer to proceed normally. 3141 A better solution is to properly configure the firewall, 3142 but sometimes that is not allowed. 3143 3144- Hashing support: 3145 CONFIG_CMD_HASH 3146 3147 This enables a generic 'hash' command which can produce 3148 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 3149 3150 CONFIG_HASH_VERIFY 3151 3152 Enable the hash verify command (hash -v). This adds to code 3153 size a little. 3154 3155 CONFIG_SHA1 - This option enables support of hashing using SHA1 3156 algorithm. The hash is calculated in software. 3157 CONFIG_SHA256 - This option enables support of hashing using 3158 SHA256 algorithm. The hash is calculated in software. 3159 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 3160 for SHA1/SHA256 hashing. 3161 This affects the 'hash' command and also the 3162 hash_lookup_algo() function. 3163 CONFIG_SHA_PROG_HW_ACCEL - This option enables 3164 hardware-acceleration for SHA1/SHA256 progressive hashing. 3165 Data can be streamed in a block at a time and the hashing 3166 is performed in hardware. 3167 3168 Note: There is also a sha1sum command, which should perhaps 3169 be deprecated in favour of 'hash sha1'. 3170 3171- Freescale i.MX specific commands: 3172 CONFIG_CMD_HDMIDETECT 3173 This enables 'hdmidet' command which returns true if an 3174 HDMI monitor is detected. This command is i.MX 6 specific. 3175 3176 CONFIG_CMD_BMODE 3177 This enables the 'bmode' (bootmode) command for forcing 3178 a boot from specific media. 3179 3180 This is useful for forcing the ROM's usb downloader to 3181 activate upon a watchdog reset which is nice when iterating 3182 on U-Boot. Using the reset button or running bmode normal 3183 will set it back to normal. This command currently 3184 supports i.MX53 and i.MX6. 3185 3186- Signing support: 3187 CONFIG_RSA 3188 3189 This enables the RSA algorithm used for FIT image verification 3190 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 3191 3192 The Modular Exponentiation algorithm in RSA is implemented using 3193 driver model. So CONFIG_DM needs to be enabled by default for this 3194 library to function. 3195 3196 The signing part is build into mkimage regardless of this 3197 option. The software based modular exponentiation is built into 3198 mkimage irrespective of this option. 3199 3200- bootcount support: 3201 CONFIG_BOOTCOUNT_LIMIT 3202 3203 This enables the bootcounter support, see: 3204 http://www.denx.de/wiki/DULG/UBootBootCountLimit 3205 3206 CONFIG_AT91SAM9XE 3207 enable special bootcounter support on at91sam9xe based boards. 3208 CONFIG_BLACKFIN 3209 enable special bootcounter support on blackfin based boards. 3210 CONFIG_SOC_DA8XX 3211 enable special bootcounter support on da850 based boards. 3212 CONFIG_BOOTCOUNT_RAM 3213 enable support for the bootcounter in RAM 3214 CONFIG_BOOTCOUNT_I2C 3215 enable support for the bootcounter on an i2c (like RTC) device. 3216 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 3217 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 3218 the bootcounter. 3219 CONFIG_BOOTCOUNT_ALEN = address len 3220 3221- Show boot progress: 3222 CONFIG_SHOW_BOOT_PROGRESS 3223 3224 Defining this option allows to add some board- 3225 specific code (calling a user-provided function 3226 "show_boot_progress(int)") that enables you to show 3227 the system's boot progress on some display (for 3228 example, some LED's) on your board. At the moment, 3229 the following checkpoints are implemented: 3230 3231 3232Legacy uImage format: 3233 3234 Arg Where When 3235 1 common/cmd_bootm.c before attempting to boot an image 3236 -1 common/cmd_bootm.c Image header has bad magic number 3237 2 common/cmd_bootm.c Image header has correct magic number 3238 -2 common/cmd_bootm.c Image header has bad checksum 3239 3 common/cmd_bootm.c Image header has correct checksum 3240 -3 common/cmd_bootm.c Image data has bad checksum 3241 4 common/cmd_bootm.c Image data has correct checksum 3242 -4 common/cmd_bootm.c Image is for unsupported architecture 3243 5 common/cmd_bootm.c Architecture check OK 3244 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3245 6 common/cmd_bootm.c Image Type check OK 3246 -6 common/cmd_bootm.c gunzip uncompression error 3247 -7 common/cmd_bootm.c Unimplemented compression type 3248 7 common/cmd_bootm.c Uncompression OK 3249 8 common/cmd_bootm.c No uncompress/copy overwrite error 3250 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3251 3252 9 common/image.c Start initial ramdisk verification 3253 -10 common/image.c Ramdisk header has bad magic number 3254 -11 common/image.c Ramdisk header has bad checksum 3255 10 common/image.c Ramdisk header is OK 3256 -12 common/image.c Ramdisk data has bad checksum 3257 11 common/image.c Ramdisk data has correct checksum 3258 12 common/image.c Ramdisk verification complete, start loading 3259 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3260 13 common/image.c Start multifile image verification 3261 14 common/image.c No initial ramdisk, no multifile, continue. 3262 3263 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3264 3265 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3266 -31 post/post.c POST test failed, detected by post_output_backlog() 3267 -32 post/post.c POST test failed, detected by post_run_single() 3268 3269 34 common/cmd_doc.c before loading a Image from a DOC device 3270 -35 common/cmd_doc.c Bad usage of "doc" command 3271 35 common/cmd_doc.c correct usage of "doc" command 3272 -36 common/cmd_doc.c No boot device 3273 36 common/cmd_doc.c correct boot device 3274 -37 common/cmd_doc.c Unknown Chip ID on boot device 3275 37 common/cmd_doc.c correct chip ID found, device available 3276 -38 common/cmd_doc.c Read Error on boot device 3277 38 common/cmd_doc.c reading Image header from DOC device OK 3278 -39 common/cmd_doc.c Image header has bad magic number 3279 39 common/cmd_doc.c Image header has correct magic number 3280 -40 common/cmd_doc.c Error reading Image from DOC device 3281 40 common/cmd_doc.c Image header has correct magic number 3282 41 common/cmd_ide.c before loading a Image from a IDE device 3283 -42 common/cmd_ide.c Bad usage of "ide" command 3284 42 common/cmd_ide.c correct usage of "ide" command 3285 -43 common/cmd_ide.c No boot device 3286 43 common/cmd_ide.c boot device found 3287 -44 common/cmd_ide.c Device not available 3288 44 common/cmd_ide.c Device available 3289 -45 common/cmd_ide.c wrong partition selected 3290 45 common/cmd_ide.c partition selected 3291 -46 common/cmd_ide.c Unknown partition table 3292 46 common/cmd_ide.c valid partition table found 3293 -47 common/cmd_ide.c Invalid partition type 3294 47 common/cmd_ide.c correct partition type 3295 -48 common/cmd_ide.c Error reading Image Header on boot device 3296 48 common/cmd_ide.c reading Image Header from IDE device OK 3297 -49 common/cmd_ide.c Image header has bad magic number 3298 49 common/cmd_ide.c Image header has correct magic number 3299 -50 common/cmd_ide.c Image header has bad checksum 3300 50 common/cmd_ide.c Image header has correct checksum 3301 -51 common/cmd_ide.c Error reading Image from IDE device 3302 51 common/cmd_ide.c reading Image from IDE device OK 3303 52 common/cmd_nand.c before loading a Image from a NAND device 3304 -53 common/cmd_nand.c Bad usage of "nand" command 3305 53 common/cmd_nand.c correct usage of "nand" command 3306 -54 common/cmd_nand.c No boot device 3307 54 common/cmd_nand.c boot device found 3308 -55 common/cmd_nand.c Unknown Chip ID on boot device 3309 55 common/cmd_nand.c correct chip ID found, device available 3310 -56 common/cmd_nand.c Error reading Image Header on boot device 3311 56 common/cmd_nand.c reading Image Header from NAND device OK 3312 -57 common/cmd_nand.c Image header has bad magic number 3313 57 common/cmd_nand.c Image header has correct magic number 3314 -58 common/cmd_nand.c Error reading Image from NAND device 3315 58 common/cmd_nand.c reading Image from NAND device OK 3316 3317 -60 common/env_common.c Environment has a bad CRC, using default 3318 3319 64 net/eth.c starting with Ethernet configuration. 3320 -64 net/eth.c no Ethernet found. 3321 65 net/eth.c Ethernet found. 3322 3323 -80 common/cmd_net.c usage wrong 3324 80 common/cmd_net.c before calling net_loop() 3325 -81 common/cmd_net.c some error in net_loop() occurred 3326 81 common/cmd_net.c net_loop() back without error 3327 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3328 82 common/cmd_net.c trying automatic boot 3329 83 common/cmd_net.c running "source" command 3330 -83 common/cmd_net.c some error in automatic boot or "source" command 3331 84 common/cmd_net.c end without errors 3332 3333FIT uImage format: 3334 3335 Arg Where When 3336 100 common/cmd_bootm.c Kernel FIT Image has correct format 3337 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3338 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3339 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3340 102 common/cmd_bootm.c Kernel unit name specified 3341 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3342 103 common/cmd_bootm.c Found configuration node 3343 104 common/cmd_bootm.c Got kernel subimage node offset 3344 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3345 105 common/cmd_bootm.c Kernel subimage hash verification OK 3346 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3347 106 common/cmd_bootm.c Architecture check OK 3348 -106 common/cmd_bootm.c Kernel subimage has wrong type 3349 107 common/cmd_bootm.c Kernel subimage type OK 3350 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3351 108 common/cmd_bootm.c Got kernel subimage data/size 3352 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3353 -109 common/cmd_bootm.c Can't get kernel subimage type 3354 -110 common/cmd_bootm.c Can't get kernel subimage comp 3355 -111 common/cmd_bootm.c Can't get kernel subimage os 3356 -112 common/cmd_bootm.c Can't get kernel subimage load address 3357 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3358 3359 120 common/image.c Start initial ramdisk verification 3360 -120 common/image.c Ramdisk FIT image has incorrect format 3361 121 common/image.c Ramdisk FIT image has correct format 3362 122 common/image.c No ramdisk subimage unit name, using configuration 3363 -122 common/image.c Can't get configuration for ramdisk subimage 3364 123 common/image.c Ramdisk unit name specified 3365 -124 common/image.c Can't get ramdisk subimage node offset 3366 125 common/image.c Got ramdisk subimage node offset 3367 -125 common/image.c Ramdisk subimage hash verification failed 3368 126 common/image.c Ramdisk subimage hash verification OK 3369 -126 common/image.c Ramdisk subimage for unsupported architecture 3370 127 common/image.c Architecture check OK 3371 -127 common/image.c Can't get ramdisk subimage data/size 3372 128 common/image.c Got ramdisk subimage data/size 3373 129 common/image.c Can't get ramdisk load address 3374 -129 common/image.c Got ramdisk load address 3375 3376 -130 common/cmd_doc.c Incorrect FIT image format 3377 131 common/cmd_doc.c FIT image format OK 3378 3379 -140 common/cmd_ide.c Incorrect FIT image format 3380 141 common/cmd_ide.c FIT image format OK 3381 3382 -150 common/cmd_nand.c Incorrect FIT image format 3383 151 common/cmd_nand.c FIT image format OK 3384 3385- legacy image format: 3386 CONFIG_IMAGE_FORMAT_LEGACY 3387 enables the legacy image format support in U-Boot. 3388 3389 Default: 3390 enabled if CONFIG_FIT_SIGNATURE is not defined. 3391 3392 CONFIG_DISABLE_IMAGE_LEGACY 3393 disable the legacy image format 3394 3395 This define is introduced, as the legacy image format is 3396 enabled per default for backward compatibility. 3397 3398- FIT image support: 3399 CONFIG_FIT 3400 Enable support for the FIT uImage format. 3401 3402 CONFIG_FIT_BEST_MATCH 3403 When no configuration is explicitly selected, default to the 3404 one whose fdt's compatibility field best matches that of 3405 U-Boot itself. A match is considered "best" if it matches the 3406 most specific compatibility entry of U-Boot's fdt's root node. 3407 The order of entries in the configuration's fdt is ignored. 3408 3409 CONFIG_FIT_SIGNATURE 3410 This option enables signature verification of FIT uImages, 3411 using a hash signed and verified using RSA. If 3412 CONFIG_SHA_PROG_HW_ACCEL is defined, i.e support for progressive 3413 hashing is available using hardware, RSA library will use it. 3414 See doc/uImage.FIT/signature.txt for more details. 3415 3416 WARNING: When relying on signed FIT images with required 3417 signature check the legacy image format is default 3418 disabled. If a board need legacy image format support 3419 enable this through CONFIG_IMAGE_FORMAT_LEGACY 3420 3421 CONFIG_FIT_DISABLE_SHA256 3422 Supporting SHA256 hashes has quite an impact on binary size. 3423 For constrained systems sha256 hash support can be disabled 3424 with this option. 3425 3426- Standalone program support: 3427 CONFIG_STANDALONE_LOAD_ADDR 3428 3429 This option defines a board specific value for the 3430 address where standalone program gets loaded, thus 3431 overwriting the architecture dependent default 3432 settings. 3433 3434- Frame Buffer Address: 3435 CONFIG_FB_ADDR 3436 3437 Define CONFIG_FB_ADDR if you want to use specific 3438 address for frame buffer. This is typically the case 3439 when using a graphics controller has separate video 3440 memory. U-Boot will then place the frame buffer at 3441 the given address instead of dynamically reserving it 3442 in system RAM by calling lcd_setmem(), which grabs 3443 the memory for the frame buffer depending on the 3444 configured panel size. 3445 3446 Please see board_init_f function. 3447 3448- Automatic software updates via TFTP server 3449 CONFIG_UPDATE_TFTP 3450 CONFIG_UPDATE_TFTP_CNT_MAX 3451 CONFIG_UPDATE_TFTP_MSEC_MAX 3452 3453 These options enable and control the auto-update feature; 3454 for a more detailed description refer to doc/README.update. 3455 3456- MTD Support (mtdparts command, UBI support) 3457 CONFIG_MTD_DEVICE 3458 3459 Adds the MTD device infrastructure from the Linux kernel. 3460 Needed for mtdparts command support. 3461 3462 CONFIG_MTD_PARTITIONS 3463 3464 Adds the MTD partitioning infrastructure from the Linux 3465 kernel. Needed for UBI support. 3466 3467- UBI support 3468 CONFIG_CMD_UBI 3469 3470 Adds commands for interacting with MTD partitions formatted 3471 with the UBI flash translation layer 3472 3473 Requires also defining CONFIG_RBTREE 3474 3475 CONFIG_UBI_SILENCE_MSG 3476 3477 Make the verbose messages from UBI stop printing. This leaves 3478 warnings and errors enabled. 3479 3480 3481 CONFIG_MTD_UBI_WL_THRESHOLD 3482 This parameter defines the maximum difference between the highest 3483 erase counter value and the lowest erase counter value of eraseblocks 3484 of UBI devices. When this threshold is exceeded, UBI starts performing 3485 wear leveling by means of moving data from eraseblock with low erase 3486 counter to eraseblocks with high erase counter. 3487 3488 The default value should be OK for SLC NAND flashes, NOR flashes and 3489 other flashes which have eraseblock life-cycle 100000 or more. 3490 However, in case of MLC NAND flashes which typically have eraseblock 3491 life-cycle less than 10000, the threshold should be lessened (e.g., 3492 to 128 or 256, although it does not have to be power of 2). 3493 3494 default: 4096 3495 3496 CONFIG_MTD_UBI_BEB_LIMIT 3497 This option specifies the maximum bad physical eraseblocks UBI 3498 expects on the MTD device (per 1024 eraseblocks). If the 3499 underlying flash does not admit of bad eraseblocks (e.g. NOR 3500 flash), this value is ignored. 3501 3502 NAND datasheets often specify the minimum and maximum NVM 3503 (Number of Valid Blocks) for the flashes' endurance lifetime. 3504 The maximum expected bad eraseblocks per 1024 eraseblocks 3505 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3506 which gives 20 for most NANDs (MaxNVB is basically the total 3507 count of eraseblocks on the chip). 3508 3509 To put it differently, if this value is 20, UBI will try to 3510 reserve about 1.9% of physical eraseblocks for bad blocks 3511 handling. And that will be 1.9% of eraseblocks on the entire 3512 NAND chip, not just the MTD partition UBI attaches. This means 3513 that if you have, say, a NAND flash chip admits maximum 40 bad 3514 eraseblocks, and it is split on two MTD partitions of the same 3515 size, UBI will reserve 40 eraseblocks when attaching a 3516 partition. 3517 3518 default: 20 3519 3520 CONFIG_MTD_UBI_FASTMAP 3521 Fastmap is a mechanism which allows attaching an UBI device 3522 in nearly constant time. Instead of scanning the whole MTD device it 3523 only has to locate a checkpoint (called fastmap) on the device. 3524 The on-flash fastmap contains all information needed to attach 3525 the device. Using fastmap makes only sense on large devices where 3526 attaching by scanning takes long. UBI will not automatically install 3527 a fastmap on old images, but you can set the UBI parameter 3528 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3529 that fastmap-enabled images are still usable with UBI implementations 3530 without fastmap support. On typical flash devices the whole fastmap 3531 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3532 3533 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3534 Set this parameter to enable fastmap automatically on images 3535 without a fastmap. 3536 default: 0 3537 3538- UBIFS support 3539 CONFIG_CMD_UBIFS 3540 3541 Adds commands for interacting with UBI volumes formatted as 3542 UBIFS. UBIFS is read-only in u-boot. 3543 3544 Requires UBI support as well as CONFIG_LZO 3545 3546 CONFIG_UBIFS_SILENCE_MSG 3547 3548 Make the verbose messages from UBIFS stop printing. This leaves 3549 warnings and errors enabled. 3550 3551- SPL framework 3552 CONFIG_SPL 3553 Enable building of SPL globally. 3554 3555 CONFIG_SPL_LDSCRIPT 3556 LDSCRIPT for linking the SPL binary. 3557 3558 CONFIG_SPL_MAX_FOOTPRINT 3559 Maximum size in memory allocated to the SPL, BSS included. 3560 When defined, the linker checks that the actual memory 3561 used by SPL from _start to __bss_end does not exceed it. 3562 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3563 must not be both defined at the same time. 3564 3565 CONFIG_SPL_MAX_SIZE 3566 Maximum size of the SPL image (text, data, rodata, and 3567 linker lists sections), BSS excluded. 3568 When defined, the linker checks that the actual size does 3569 not exceed it. 3570 3571 CONFIG_SPL_TEXT_BASE 3572 TEXT_BASE for linking the SPL binary. 3573 3574 CONFIG_SPL_RELOC_TEXT_BASE 3575 Address to relocate to. If unspecified, this is equal to 3576 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3577 3578 CONFIG_SPL_BSS_START_ADDR 3579 Link address for the BSS within the SPL binary. 3580 3581 CONFIG_SPL_BSS_MAX_SIZE 3582 Maximum size in memory allocated to the SPL BSS. 3583 When defined, the linker checks that the actual memory used 3584 by SPL from __bss_start to __bss_end does not exceed it. 3585 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3586 must not be both defined at the same time. 3587 3588 CONFIG_SPL_STACK 3589 Adress of the start of the stack SPL will use 3590 3591 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3592 When defined, SPL will panic() if the image it has 3593 loaded does not have a signature. 3594 Defining this is useful when code which loads images 3595 in SPL cannot guarantee that absolutely all read errors 3596 will be caught. 3597 An example is the LPC32XX MLC NAND driver, which will 3598 consider that a completely unreadable NAND block is bad, 3599 and thus should be skipped silently. 3600 3601 CONFIG_SPL_RELOC_STACK 3602 Adress of the start of the stack SPL will use after 3603 relocation. If unspecified, this is equal to 3604 CONFIG_SPL_STACK. 3605 3606 CONFIG_SYS_SPL_MALLOC_START 3607 Starting address of the malloc pool used in SPL. 3608 3609 CONFIG_SYS_SPL_MALLOC_SIZE 3610 The size of the malloc pool used in SPL. 3611 3612 CONFIG_SPL_FRAMEWORK 3613 Enable the SPL framework under common/. This framework 3614 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3615 NAND loading of the Linux Kernel. 3616 3617 CONFIG_SPL_OS_BOOT 3618 Enable booting directly to an OS from SPL. 3619 See also: doc/README.falcon 3620 3621 CONFIG_SPL_DISPLAY_PRINT 3622 For ARM, enable an optional function to print more information 3623 about the running system. 3624 3625 CONFIG_SPL_INIT_MINIMAL 3626 Arch init code should be built for a very small image 3627 3628 CONFIG_SPL_LIBCOMMON_SUPPORT 3629 Support for common/libcommon.o in SPL binary 3630 3631 CONFIG_SPL_LIBDISK_SUPPORT 3632 Support for disk/libdisk.o in SPL binary 3633 3634 CONFIG_SPL_I2C_SUPPORT 3635 Support for drivers/i2c/libi2c.o in SPL binary 3636 3637 CONFIG_SPL_GPIO_SUPPORT 3638 Support for drivers/gpio/libgpio.o in SPL binary 3639 3640 CONFIG_SPL_MMC_SUPPORT 3641 Support for drivers/mmc/libmmc.o in SPL binary 3642 3643 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3644 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3645 Address and partition on the MMC to load U-Boot from 3646 when the MMC is being used in raw mode. 3647 3648 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3649 Partition on the MMC to load U-Boot from when the MMC is being 3650 used in raw mode 3651 3652 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3653 Sector to load kernel uImage from when MMC is being 3654 used in raw mode (for Falcon mode) 3655 3656 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3657 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3658 Sector and number of sectors to load kernel argument 3659 parameters from when MMC is being used in raw mode 3660 (for falcon mode) 3661 3662 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3663 Partition on the MMC to load U-Boot from when the MMC is being 3664 used in fs mode 3665 3666 CONFIG_SPL_FAT_SUPPORT 3667 Support for fs/fat/libfat.o in SPL binary 3668 3669 CONFIG_SPL_EXT_SUPPORT 3670 Support for EXT filesystem in SPL binary 3671 3672 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3673 Filename to read to load U-Boot when reading from filesystem 3674 3675 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3676 Filename to read to load kernel uImage when reading 3677 from filesystem (for Falcon mode) 3678 3679 CONFIG_SPL_FS_LOAD_ARGS_NAME 3680 Filename to read to load kernel argument parameters 3681 when reading from filesystem (for Falcon mode) 3682 3683 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3684 Set this for NAND SPL on PPC mpc83xx targets, so that 3685 start.S waits for the rest of the SPL to load before 3686 continuing (the hardware starts execution after just 3687 loading the first page rather than the full 4K). 3688 3689 CONFIG_SPL_SKIP_RELOCATE 3690 Avoid SPL relocation 3691 3692 CONFIG_SPL_NAND_BASE 3693 Include nand_base.c in the SPL. Requires 3694 CONFIG_SPL_NAND_DRIVERS. 3695 3696 CONFIG_SPL_NAND_DRIVERS 3697 SPL uses normal NAND drivers, not minimal drivers. 3698 3699 CONFIG_SPL_NAND_ECC 3700 Include standard software ECC in the SPL 3701 3702 CONFIG_SPL_NAND_SIMPLE 3703 Support for NAND boot using simple NAND drivers that 3704 expose the cmd_ctrl() interface. 3705 3706 CONFIG_SPL_MTD_SUPPORT 3707 Support for the MTD subsystem within SPL. Useful for 3708 environment on NAND support within SPL. 3709 3710 CONFIG_SPL_NAND_RAW_ONLY 3711 Support to boot only raw u-boot.bin images. Use this only 3712 if you need to save space. 3713 3714 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3715 Set for the SPL on PPC mpc8xxx targets, support for 3716 drivers/ddr/fsl/libddr.o in SPL binary. 3717 3718 CONFIG_SPL_COMMON_INIT_DDR 3719 Set for common ddr init with serial presence detect in 3720 SPL binary. 3721 3722 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3723 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3724 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3725 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3726 CONFIG_SYS_NAND_ECCBYTES 3727 Defines the size and behavior of the NAND that SPL uses 3728 to read U-Boot 3729 3730 CONFIG_SPL_NAND_BOOT 3731 Add support NAND boot 3732 3733 CONFIG_SYS_NAND_U_BOOT_OFFS 3734 Location in NAND to read U-Boot from 3735 3736 CONFIG_SYS_NAND_U_BOOT_DST 3737 Location in memory to load U-Boot to 3738 3739 CONFIG_SYS_NAND_U_BOOT_SIZE 3740 Size of image to load 3741 3742 CONFIG_SYS_NAND_U_BOOT_START 3743 Entry point in loaded image to jump to 3744 3745 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3746 Define this if you need to first read the OOB and then the 3747 data. This is used, for example, on davinci platforms. 3748 3749 CONFIG_SPL_OMAP3_ID_NAND 3750 Support for an OMAP3-specific set of functions to return the 3751 ID and MFR of the first attached NAND chip, if present. 3752 3753 CONFIG_SPL_SERIAL_SUPPORT 3754 Support for drivers/serial/libserial.o in SPL binary 3755 3756 CONFIG_SPL_SPI_FLASH_SUPPORT 3757 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3758 3759 CONFIG_SPL_SPI_SUPPORT 3760 Support for drivers/spi/libspi.o in SPL binary 3761 3762 CONFIG_SPL_RAM_DEVICE 3763 Support for running image already present in ram, in SPL binary 3764 3765 CONFIG_SPL_LIBGENERIC_SUPPORT 3766 Support for lib/libgeneric.o in SPL binary 3767 3768 CONFIG_SPL_ENV_SUPPORT 3769 Support for the environment operating in SPL binary 3770 3771 CONFIG_SPL_NET_SUPPORT 3772 Support for the net/libnet.o in SPL binary. 3773 It conflicts with SPL env from storage medium specified by 3774 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3775 3776 CONFIG_SPL_PAD_TO 3777 Image offset to which the SPL should be padded before appending 3778 the SPL payload. By default, this is defined as 3779 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3780 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3781 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3782 3783 CONFIG_SPL_TARGET 3784 Final target image containing SPL and payload. Some SPLs 3785 use an arch-specific makefile fragment instead, for 3786 example if more than one image needs to be produced. 3787 3788 CONFIG_FIT_SPL_PRINT 3789 Printing information about a FIT image adds quite a bit of 3790 code to SPL. So this is normally disabled in SPL. Use this 3791 option to re-enable it. This will affect the output of the 3792 bootm command when booting a FIT image. 3793 3794- TPL framework 3795 CONFIG_TPL 3796 Enable building of TPL globally. 3797 3798 CONFIG_TPL_PAD_TO 3799 Image offset to which the TPL should be padded before appending 3800 the TPL payload. By default, this is defined as 3801 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3802 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3803 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3804 3805Modem Support: 3806-------------- 3807 3808[so far only for SMDK2400 boards] 3809 3810- Modem support enable: 3811 CONFIG_MODEM_SUPPORT 3812 3813- RTS/CTS Flow control enable: 3814 CONFIG_HWFLOW 3815 3816- Modem debug support: 3817 CONFIG_MODEM_SUPPORT_DEBUG 3818 3819 Enables debugging stuff (char screen[1024], dbg()) 3820 for modem support. Useful only with BDI2000. 3821 3822- Interrupt support (PPC): 3823 3824 There are common interrupt_init() and timer_interrupt() 3825 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3826 for CPU specific initialization. interrupt_init_cpu() 3827 should set decrementer_count to appropriate value. If 3828 CPU resets decrementer automatically after interrupt 3829 (ppc4xx) it should set decrementer_count to zero. 3830 timer_interrupt() calls timer_interrupt_cpu() for CPU 3831 specific handling. If board has watchdog / status_led 3832 / other_activity_monitor it works automatically from 3833 general timer_interrupt(). 3834 3835- General: 3836 3837 In the target system modem support is enabled when a 3838 specific key (key combination) is pressed during 3839 power-on. Otherwise U-Boot will boot normally 3840 (autoboot). The key_pressed() function is called from 3841 board_init(). Currently key_pressed() is a dummy 3842 function, returning 1 and thus enabling modem 3843 initialization. 3844 3845 If there are no modem init strings in the 3846 environment, U-Boot proceed to autoboot; the 3847 previous output (banner, info printfs) will be 3848 suppressed, though. 3849 3850 See also: doc/README.Modem 3851 3852Board initialization settings: 3853------------------------------ 3854 3855During Initialization u-boot calls a number of board specific functions 3856to allow the preparation of board specific prerequisites, e.g. pin setup 3857before drivers are initialized. To enable these callbacks the 3858following configuration macros have to be defined. Currently this is 3859architecture specific, so please check arch/your_architecture/lib/board.c 3860typically in board_init_f() and board_init_r(). 3861 3862- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3863- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3864- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3865- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3866 3867Configuration Settings: 3868----------------------- 3869 3870- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3871 Optionally it can be defined to support 64-bit memory commands. 3872 3873- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3874 undefine this when you're short of memory. 3875 3876- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3877 width of the commands listed in the 'help' command output. 3878 3879- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3880 prompt for user input. 3881 3882- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3883 3884- CONFIG_SYS_PBSIZE: Buffer size for Console output 3885 3886- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3887 3888- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3889 the application (usually a Linux kernel) when it is 3890 booted 3891 3892- CONFIG_SYS_BAUDRATE_TABLE: 3893 List of legal baudrate settings for this board. 3894 3895- CONFIG_SYS_CONSOLE_INFO_QUIET 3896 Suppress display of console information at boot. 3897 3898- CONFIG_SYS_CONSOLE_IS_IN_ENV 3899 If the board specific function 3900 extern int overwrite_console (void); 3901 returns 1, the stdin, stderr and stdout are switched to the 3902 serial port, else the settings in the environment are used. 3903 3904- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3905 Enable the call to overwrite_console(). 3906 3907- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3908 Enable overwrite of previous console environment settings. 3909 3910- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3911 Begin and End addresses of the area used by the 3912 simple memory test. 3913 3914- CONFIG_SYS_ALT_MEMTEST: 3915 Enable an alternate, more extensive memory test. 3916 3917- CONFIG_SYS_MEMTEST_SCRATCH: 3918 Scratch address used by the alternate memory test 3919 You only need to set this if address zero isn't writeable 3920 3921- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3922 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3923 this specified memory area will get subtracted from the top 3924 (end) of RAM and won't get "touched" at all by U-Boot. By 3925 fixing up gd->ram_size the Linux kernel should gets passed 3926 the now "corrected" memory size and won't touch it either. 3927 This should work for arch/ppc and arch/powerpc. Only Linux 3928 board ports in arch/powerpc with bootwrapper support that 3929 recalculate the memory size from the SDRAM controller setup 3930 will have to get fixed in Linux additionally. 3931 3932 This option can be used as a workaround for the 440EPx/GRx 3933 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3934 be touched. 3935 3936 WARNING: Please make sure that this value is a multiple of 3937 the Linux page size (normally 4k). If this is not the case, 3938 then the end address of the Linux memory will be located at a 3939 non page size aligned address and this could cause major 3940 problems. 3941 3942- CONFIG_SYS_LOADS_BAUD_CHANGE: 3943 Enable temporary baudrate change while serial download 3944 3945- CONFIG_SYS_SDRAM_BASE: 3946 Physical start address of SDRAM. _Must_ be 0 here. 3947 3948- CONFIG_SYS_MBIO_BASE: 3949 Physical start address of Motherboard I/O (if using a 3950 Cogent motherboard) 3951 3952- CONFIG_SYS_FLASH_BASE: 3953 Physical start address of Flash memory. 3954 3955- CONFIG_SYS_MONITOR_BASE: 3956 Physical start address of boot monitor code (set by 3957 make config files to be same as the text base address 3958 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3959 CONFIG_SYS_FLASH_BASE when booting from flash. 3960 3961- CONFIG_SYS_MONITOR_LEN: 3962 Size of memory reserved for monitor code, used to 3963 determine _at_compile_time_ (!) if the environment is 3964 embedded within the U-Boot image, or in a separate 3965 flash sector. 3966 3967- CONFIG_SYS_MALLOC_LEN: 3968 Size of DRAM reserved for malloc() use. 3969 3970- CONFIG_SYS_MALLOC_F_LEN 3971 Size of the malloc() pool for use before relocation. If 3972 this is defined, then a very simple malloc() implementation 3973 will become available before relocation. The address is just 3974 below the global data, and the stack is moved down to make 3975 space. 3976 3977 This feature allocates regions with increasing addresses 3978 within the region. calloc() is supported, but realloc() 3979 is not available. free() is supported but does nothing. 3980 The memory will be freed (or in fact just forgotten) when 3981 U-Boot relocates itself. 3982 3983 Pre-relocation malloc() is only supported on ARM and sandbox 3984 at present but is fairly easy to enable for other archs. 3985 3986- CONFIG_SYS_MALLOC_SIMPLE 3987 Provides a simple and small malloc() and calloc() for those 3988 boards which do not use the full malloc in SPL (which is 3989 enabled with CONFIG_SYS_SPL_MALLOC_START). 3990 3991- CONFIG_SYS_NONCACHED_MEMORY: 3992 Size of non-cached memory area. This area of memory will be 3993 typically located right below the malloc() area and mapped 3994 uncached in the MMU. This is useful for drivers that would 3995 otherwise require a lot of explicit cache maintenance. For 3996 some drivers it's also impossible to properly maintain the 3997 cache. For example if the regions that need to be flushed 3998 are not a multiple of the cache-line size, *and* padding 3999 cannot be allocated between the regions to align them (i.e. 4000 if the HW requires a contiguous array of regions, and the 4001 size of each region is not cache-aligned), then a flush of 4002 one region may result in overwriting data that hardware has 4003 written to another region in the same cache-line. This can 4004 happen for example in network drivers where descriptors for 4005 buffers are typically smaller than the CPU cache-line (e.g. 4006 16 bytes vs. 32 or 64 bytes). 4007 4008 Non-cached memory is only supported on 32-bit ARM at present. 4009 4010- CONFIG_SYS_BOOTM_LEN: 4011 Normally compressed uImages are limited to an 4012 uncompressed size of 8 MBytes. If this is not enough, 4013 you can define CONFIG_SYS_BOOTM_LEN in your board config file 4014 to adjust this setting to your needs. 4015 4016- CONFIG_SYS_BOOTMAPSZ: 4017 Maximum size of memory mapped by the startup code of 4018 the Linux kernel; all data that must be processed by 4019 the Linux kernel (bd_info, boot arguments, FDT blob if 4020 used) must be put below this limit, unless "bootm_low" 4021 environment variable is defined and non-zero. In such case 4022 all data for the Linux kernel must be between "bootm_low" 4023 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 4024 variable "bootm_mapsize" will override the value of 4025 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 4026 then the value in "bootm_size" will be used instead. 4027 4028- CONFIG_SYS_BOOT_RAMDISK_HIGH: 4029 Enable initrd_high functionality. If defined then the 4030 initrd_high feature is enabled and the bootm ramdisk subcommand 4031 is enabled. 4032 4033- CONFIG_SYS_BOOT_GET_CMDLINE: 4034 Enables allocating and saving kernel cmdline in space between 4035 "bootm_low" and "bootm_low" + BOOTMAPSZ. 4036 4037- CONFIG_SYS_BOOT_GET_KBD: 4038 Enables allocating and saving a kernel copy of the bd_info in 4039 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 4040 4041- CONFIG_SYS_MAX_FLASH_BANKS: 4042 Max number of Flash memory banks 4043 4044- CONFIG_SYS_MAX_FLASH_SECT: 4045 Max number of sectors on a Flash chip 4046 4047- CONFIG_SYS_FLASH_ERASE_TOUT: 4048 Timeout for Flash erase operations (in ms) 4049 4050- CONFIG_SYS_FLASH_WRITE_TOUT: 4051 Timeout for Flash write operations (in ms) 4052 4053- CONFIG_SYS_FLASH_LOCK_TOUT 4054 Timeout for Flash set sector lock bit operation (in ms) 4055 4056- CONFIG_SYS_FLASH_UNLOCK_TOUT 4057 Timeout for Flash clear lock bits operation (in ms) 4058 4059- CONFIG_SYS_FLASH_PROTECTION 4060 If defined, hardware flash sectors protection is used 4061 instead of U-Boot software protection. 4062 4063- CONFIG_SYS_DIRECT_FLASH_TFTP: 4064 4065 Enable TFTP transfers directly to flash memory; 4066 without this option such a download has to be 4067 performed in two steps: (1) download to RAM, and (2) 4068 copy from RAM to flash. 4069 4070 The two-step approach is usually more reliable, since 4071 you can check if the download worked before you erase 4072 the flash, but in some situations (when system RAM is 4073 too limited to allow for a temporary copy of the 4074 downloaded image) this option may be very useful. 4075 4076- CONFIG_SYS_FLASH_CFI: 4077 Define if the flash driver uses extra elements in the 4078 common flash structure for storing flash geometry. 4079 4080- CONFIG_FLASH_CFI_DRIVER 4081 This option also enables the building of the cfi_flash driver 4082 in the drivers directory 4083 4084- CONFIG_FLASH_CFI_MTD 4085 This option enables the building of the cfi_mtd driver 4086 in the drivers directory. The driver exports CFI flash 4087 to the MTD layer. 4088 4089- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 4090 Use buffered writes to flash. 4091 4092- CONFIG_FLASH_SPANSION_S29WS_N 4093 s29ws-n MirrorBit flash has non-standard addresses for buffered 4094 write commands. 4095 4096- CONFIG_SYS_FLASH_QUIET_TEST 4097 If this option is defined, the common CFI flash doesn't 4098 print it's warning upon not recognized FLASH banks. This 4099 is useful, if some of the configured banks are only 4100 optionally available. 4101 4102- CONFIG_FLASH_SHOW_PROGRESS 4103 If defined (must be an integer), print out countdown 4104 digits and dots. Recommended value: 45 (9..1) for 80 4105 column displays, 15 (3..1) for 40 column displays. 4106 4107- CONFIG_FLASH_VERIFY 4108 If defined, the content of the flash (destination) is compared 4109 against the source after the write operation. An error message 4110 will be printed when the contents are not identical. 4111 Please note that this option is useless in nearly all cases, 4112 since such flash programming errors usually are detected earlier 4113 while unprotecting/erasing/programming. Please only enable 4114 this option if you really know what you are doing. 4115 4116- CONFIG_SYS_RX_ETH_BUFFER: 4117 Defines the number of Ethernet receive buffers. On some 4118 Ethernet controllers it is recommended to set this value 4119 to 8 or even higher (EEPRO100 or 405 EMAC), since all 4120 buffers can be full shortly after enabling the interface 4121 on high Ethernet traffic. 4122 Defaults to 4 if not defined. 4123 4124- CONFIG_ENV_MAX_ENTRIES 4125 4126 Maximum number of entries in the hash table that is used 4127 internally to store the environment settings. The default 4128 setting is supposed to be generous and should work in most 4129 cases. This setting can be used to tune behaviour; see 4130 lib/hashtable.c for details. 4131 4132- CONFIG_ENV_FLAGS_LIST_DEFAULT 4133- CONFIG_ENV_FLAGS_LIST_STATIC 4134 Enable validation of the values given to environment variables when 4135 calling env set. Variables can be restricted to only decimal, 4136 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 4137 the variables can also be restricted to IP address or MAC address. 4138 4139 The format of the list is: 4140 type_attribute = [s|d|x|b|i|m] 4141 access_attribute = [a|r|o|c] 4142 attributes = type_attribute[access_attribute] 4143 entry = variable_name[:attributes] 4144 list = entry[,list] 4145 4146 The type attributes are: 4147 s - String (default) 4148 d - Decimal 4149 x - Hexadecimal 4150 b - Boolean ([1yYtT|0nNfF]) 4151 i - IP address 4152 m - MAC address 4153 4154 The access attributes are: 4155 a - Any (default) 4156 r - Read-only 4157 o - Write-once 4158 c - Change-default 4159 4160 - CONFIG_ENV_FLAGS_LIST_DEFAULT 4161 Define this to a list (string) to define the ".flags" 4162 environment variable in the default or embedded environment. 4163 4164 - CONFIG_ENV_FLAGS_LIST_STATIC 4165 Define this to a list (string) to define validation that 4166 should be done if an entry is not found in the ".flags" 4167 environment variable. To override a setting in the static 4168 list, simply add an entry for the same variable name to the 4169 ".flags" variable. 4170 4171- CONFIG_ENV_ACCESS_IGNORE_FORCE 4172 If defined, don't allow the -f switch to env set override variable 4173 access flags. 4174 4175- CONFIG_SYS_GENERIC_BOARD 4176 This selects the architecture-generic board system instead of the 4177 architecture-specific board files. It is intended to move boards 4178 to this new framework over time. Defining this will disable the 4179 arch/foo/lib/board.c file and use common/board_f.c and 4180 common/board_r.c instead. To use this option your architecture 4181 must support it (i.e. must select HAVE_GENERIC_BOARD in arch/Kconfig). 4182 If you find problems enabling this option on your board please report 4183 the problem and send patches! 4184 4185- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 4186 This is set by OMAP boards for the max time that reset should 4187 be asserted. See doc/README.omap-reset-time for details on how 4188 the value can be calculated on a given board. 4189 4190- CONFIG_USE_STDINT 4191 If stdint.h is available with your toolchain you can define this 4192 option to enable it. You can provide option 'USE_STDINT=1' when 4193 building U-Boot to enable this. 4194 4195The following definitions that deal with the placement and management 4196of environment data (variable area); in general, we support the 4197following configurations: 4198 4199- CONFIG_BUILD_ENVCRC: 4200 4201 Builds up envcrc with the target environment so that external utils 4202 may easily extract it and embed it in final U-Boot images. 4203 4204- CONFIG_ENV_IS_IN_FLASH: 4205 4206 Define this if the environment is in flash memory. 4207 4208 a) The environment occupies one whole flash sector, which is 4209 "embedded" in the text segment with the U-Boot code. This 4210 happens usually with "bottom boot sector" or "top boot 4211 sector" type flash chips, which have several smaller 4212 sectors at the start or the end. For instance, such a 4213 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 4214 such a case you would place the environment in one of the 4215 4 kB sectors - with U-Boot code before and after it. With 4216 "top boot sector" type flash chips, you would put the 4217 environment in one of the last sectors, leaving a gap 4218 between U-Boot and the environment. 4219 4220 - CONFIG_ENV_OFFSET: 4221 4222 Offset of environment data (variable area) to the 4223 beginning of flash memory; for instance, with bottom boot 4224 type flash chips the second sector can be used: the offset 4225 for this sector is given here. 4226 4227 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 4228 4229 - CONFIG_ENV_ADDR: 4230 4231 This is just another way to specify the start address of 4232 the flash sector containing the environment (instead of 4233 CONFIG_ENV_OFFSET). 4234 4235 - CONFIG_ENV_SECT_SIZE: 4236 4237 Size of the sector containing the environment. 4238 4239 4240 b) Sometimes flash chips have few, equal sized, BIG sectors. 4241 In such a case you don't want to spend a whole sector for 4242 the environment. 4243 4244 - CONFIG_ENV_SIZE: 4245 4246 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 4247 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 4248 of this flash sector for the environment. This saves 4249 memory for the RAM copy of the environment. 4250 4251 It may also save flash memory if you decide to use this 4252 when your environment is "embedded" within U-Boot code, 4253 since then the remainder of the flash sector could be used 4254 for U-Boot code. It should be pointed out that this is 4255 STRONGLY DISCOURAGED from a robustness point of view: 4256 updating the environment in flash makes it always 4257 necessary to erase the WHOLE sector. If something goes 4258 wrong before the contents has been restored from a copy in 4259 RAM, your target system will be dead. 4260 4261 - CONFIG_ENV_ADDR_REDUND 4262 CONFIG_ENV_SIZE_REDUND 4263 4264 These settings describe a second storage area used to hold 4265 a redundant copy of the environment data, so that there is 4266 a valid backup copy in case there is a power failure during 4267 a "saveenv" operation. 4268 4269BE CAREFUL! Any changes to the flash layout, and some changes to the 4270source code will make it necessary to adapt <board>/u-boot.lds* 4271accordingly! 4272 4273 4274- CONFIG_ENV_IS_IN_NVRAM: 4275 4276 Define this if you have some non-volatile memory device 4277 (NVRAM, battery buffered SRAM) which you want to use for the 4278 environment. 4279 4280 - CONFIG_ENV_ADDR: 4281 - CONFIG_ENV_SIZE: 4282 4283 These two #defines are used to determine the memory area you 4284 want to use for environment. It is assumed that this memory 4285 can just be read and written to, without any special 4286 provision. 4287 4288BE CAREFUL! The first access to the environment happens quite early 4289in U-Boot initialization (when we try to get the setting of for the 4290console baudrate). You *MUST* have mapped your NVRAM area then, or 4291U-Boot will hang. 4292 4293Please note that even with NVRAM we still use a copy of the 4294environment in RAM: we could work on NVRAM directly, but we want to 4295keep settings there always unmodified except somebody uses "saveenv" 4296to save the current settings. 4297 4298 4299- CONFIG_ENV_IS_IN_EEPROM: 4300 4301 Use this if you have an EEPROM or similar serial access 4302 device and a driver for it. 4303 4304 - CONFIG_ENV_OFFSET: 4305 - CONFIG_ENV_SIZE: 4306 4307 These two #defines specify the offset and size of the 4308 environment area within the total memory of your EEPROM. 4309 4310 - CONFIG_SYS_I2C_EEPROM_ADDR: 4311 If defined, specified the chip address of the EEPROM device. 4312 The default address is zero. 4313 4314 - CONFIG_SYS_I2C_EEPROM_BUS: 4315 If defined, specified the i2c bus of the EEPROM device. 4316 4317 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 4318 If defined, the number of bits used to address bytes in a 4319 single page in the EEPROM device. A 64 byte page, for example 4320 would require six bits. 4321 4322 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 4323 If defined, the number of milliseconds to delay between 4324 page writes. The default is zero milliseconds. 4325 4326 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 4327 The length in bytes of the EEPROM memory array address. Note 4328 that this is NOT the chip address length! 4329 4330 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 4331 EEPROM chips that implement "address overflow" are ones 4332 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 4333 address and the extra bits end up in the "chip address" bit 4334 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 4335 byte chips. 4336 4337 Note that we consider the length of the address field to 4338 still be one byte because the extra address bits are hidden 4339 in the chip address. 4340 4341 - CONFIG_SYS_EEPROM_SIZE: 4342 The size in bytes of the EEPROM device. 4343 4344 - CONFIG_ENV_EEPROM_IS_ON_I2C 4345 define this, if you have I2C and SPI activated, and your 4346 EEPROM, which holds the environment, is on the I2C bus. 4347 4348 - CONFIG_I2C_ENV_EEPROM_BUS 4349 if you have an Environment on an EEPROM reached over 4350 I2C muxes, you can define here, how to reach this 4351 EEPROM. For example: 4352 4353 #define CONFIG_I2C_ENV_EEPROM_BUS 1 4354 4355 EEPROM which holds the environment, is reached over 4356 a pca9547 i2c mux with address 0x70, channel 3. 4357 4358- CONFIG_ENV_IS_IN_DATAFLASH: 4359 4360 Define this if you have a DataFlash memory device which you 4361 want to use for the environment. 4362 4363 - CONFIG_ENV_OFFSET: 4364 - CONFIG_ENV_ADDR: 4365 - CONFIG_ENV_SIZE: 4366 4367 These three #defines specify the offset and size of the 4368 environment area within the total memory of your DataFlash placed 4369 at the specified address. 4370 4371- CONFIG_ENV_IS_IN_SPI_FLASH: 4372 4373 Define this if you have a SPI Flash memory device which you 4374 want to use for the environment. 4375 4376 - CONFIG_ENV_OFFSET: 4377 - CONFIG_ENV_SIZE: 4378 4379 These two #defines specify the offset and size of the 4380 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 4381 aligned to an erase sector boundary. 4382 4383 - CONFIG_ENV_SECT_SIZE: 4384 4385 Define the SPI flash's sector size. 4386 4387 - CONFIG_ENV_OFFSET_REDUND (optional): 4388 4389 This setting describes a second storage area of CONFIG_ENV_SIZE 4390 size used to hold a redundant copy of the environment data, so 4391 that there is a valid backup copy in case there is a power failure 4392 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4393 aligned to an erase sector boundary. 4394 4395 - CONFIG_ENV_SPI_BUS (optional): 4396 - CONFIG_ENV_SPI_CS (optional): 4397 4398 Define the SPI bus and chip select. If not defined they will be 0. 4399 4400 - CONFIG_ENV_SPI_MAX_HZ (optional): 4401 4402 Define the SPI max work clock. If not defined then use 1MHz. 4403 4404 - CONFIG_ENV_SPI_MODE (optional): 4405 4406 Define the SPI work mode. If not defined then use SPI_MODE_3. 4407 4408- CONFIG_ENV_IS_IN_REMOTE: 4409 4410 Define this if you have a remote memory space which you 4411 want to use for the local device's environment. 4412 4413 - CONFIG_ENV_ADDR: 4414 - CONFIG_ENV_SIZE: 4415 4416 These two #defines specify the address and size of the 4417 environment area within the remote memory space. The 4418 local device can get the environment from remote memory 4419 space by SRIO or PCIE links. 4420 4421BE CAREFUL! For some special cases, the local device can not use 4422"saveenv" command. For example, the local device will get the 4423environment stored in a remote NOR flash by SRIO or PCIE link, 4424but it can not erase, write this NOR flash by SRIO or PCIE interface. 4425 4426- CONFIG_ENV_IS_IN_NAND: 4427 4428 Define this if you have a NAND device which you want to use 4429 for the environment. 4430 4431 - CONFIG_ENV_OFFSET: 4432 - CONFIG_ENV_SIZE: 4433 4434 These two #defines specify the offset and size of the environment 4435 area within the first NAND device. CONFIG_ENV_OFFSET must be 4436 aligned to an erase block boundary. 4437 4438 - CONFIG_ENV_OFFSET_REDUND (optional): 4439 4440 This setting describes a second storage area of CONFIG_ENV_SIZE 4441 size used to hold a redundant copy of the environment data, so 4442 that there is a valid backup copy in case there is a power failure 4443 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4444 aligned to an erase block boundary. 4445 4446 - CONFIG_ENV_RANGE (optional): 4447 4448 Specifies the length of the region in which the environment 4449 can be written. This should be a multiple of the NAND device's 4450 block size. Specifying a range with more erase blocks than 4451 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4452 the range to be avoided. 4453 4454 - CONFIG_ENV_OFFSET_OOB (optional): 4455 4456 Enables support for dynamically retrieving the offset of the 4457 environment from block zero's out-of-band data. The 4458 "nand env.oob" command can be used to record this offset. 4459 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4460 using CONFIG_ENV_OFFSET_OOB. 4461 4462- CONFIG_NAND_ENV_DST 4463 4464 Defines address in RAM to which the nand_spl code should copy the 4465 environment. If redundant environment is used, it will be copied to 4466 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4467 4468- CONFIG_ENV_IS_IN_UBI: 4469 4470 Define this if you have an UBI volume that you want to use for the 4471 environment. This has the benefit of wear-leveling the environment 4472 accesses, which is important on NAND. 4473 4474 - CONFIG_ENV_UBI_PART: 4475 4476 Define this to a string that is the mtd partition containing the UBI. 4477 4478 - CONFIG_ENV_UBI_VOLUME: 4479 4480 Define this to the name of the volume that you want to store the 4481 environment in. 4482 4483 - CONFIG_ENV_UBI_VOLUME_REDUND: 4484 4485 Define this to the name of another volume to store a second copy of 4486 the environment in. This will enable redundant environments in UBI. 4487 It is assumed that both volumes are in the same MTD partition. 4488 4489 - CONFIG_UBI_SILENCE_MSG 4490 - CONFIG_UBIFS_SILENCE_MSG 4491 4492 You will probably want to define these to avoid a really noisy system 4493 when storing the env in UBI. 4494 4495- CONFIG_ENV_IS_IN_FAT: 4496 Define this if you want to use the FAT file system for the environment. 4497 4498 - FAT_ENV_INTERFACE: 4499 4500 Define this to a string that is the name of the block device. 4501 4502 - FAT_ENV_DEV_AND_PART: 4503 4504 Define this to a string to specify the partition of the device. It can 4505 be as following: 4506 4507 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4508 - "D:P": device D partition P. Error occurs if device D has no 4509 partition table. 4510 - "D:0": device D. 4511 - "D" or "D:": device D partition 1 if device D has partition 4512 table, or the whole device D if has no partition 4513 table. 4514 - "D:auto": first partition in device D with bootable flag set. 4515 If none, first valid partition in device D. If no 4516 partition table then means device D. 4517 4518 - FAT_ENV_FILE: 4519 4520 It's a string of the FAT file name. This file use to store the 4521 environment. 4522 4523 - CONFIG_FAT_WRITE: 4524 This should be defined. Otherwise it cannot save the environment file. 4525 4526- CONFIG_ENV_IS_IN_MMC: 4527 4528 Define this if you have an MMC device which you want to use for the 4529 environment. 4530 4531 - CONFIG_SYS_MMC_ENV_DEV: 4532 4533 Specifies which MMC device the environment is stored in. 4534 4535 - CONFIG_SYS_MMC_ENV_PART (optional): 4536 4537 Specifies which MMC partition the environment is stored in. If not 4538 set, defaults to partition 0, the user area. Common values might be 4539 1 (first MMC boot partition), 2 (second MMC boot partition). 4540 4541 - CONFIG_ENV_OFFSET: 4542 - CONFIG_ENV_SIZE: 4543 4544 These two #defines specify the offset and size of the environment 4545 area within the specified MMC device. 4546 4547 If offset is positive (the usual case), it is treated as relative to 4548 the start of the MMC partition. If offset is negative, it is treated 4549 as relative to the end of the MMC partition. This can be useful if 4550 your board may be fitted with different MMC devices, which have 4551 different sizes for the MMC partitions, and you always want the 4552 environment placed at the very end of the partition, to leave the 4553 maximum possible space before it, to store other data. 4554 4555 These two values are in units of bytes, but must be aligned to an 4556 MMC sector boundary. 4557 4558 - CONFIG_ENV_OFFSET_REDUND (optional): 4559 4560 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4561 hold a redundant copy of the environment data. This provides a 4562 valid backup copy in case the other copy is corrupted, e.g. due 4563 to a power failure during a "saveenv" operation. 4564 4565 This value may also be positive or negative; this is handled in the 4566 same way as CONFIG_ENV_OFFSET. 4567 4568 This value is also in units of bytes, but must also be aligned to 4569 an MMC sector boundary. 4570 4571 - CONFIG_ENV_SIZE_REDUND (optional): 4572 4573 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4574 set. If this value is set, it must be set to the same value as 4575 CONFIG_ENV_SIZE. 4576 4577- CONFIG_SYS_SPI_INIT_OFFSET 4578 4579 Defines offset to the initial SPI buffer area in DPRAM. The 4580 area is used at an early stage (ROM part) if the environment 4581 is configured to reside in the SPI EEPROM: We need a 520 byte 4582 scratch DPRAM area. It is used between the two initialization 4583 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4584 to be a good choice since it makes it far enough from the 4585 start of the data area as well as from the stack pointer. 4586 4587Please note that the environment is read-only until the monitor 4588has been relocated to RAM and a RAM copy of the environment has been 4589created; also, when using EEPROM you will have to use getenv_f() 4590until then to read environment variables. 4591 4592The environment is protected by a CRC32 checksum. Before the monitor 4593is relocated into RAM, as a result of a bad CRC you will be working 4594with the compiled-in default environment - *silently*!!! [This is 4595necessary, because the first environment variable we need is the 4596"baudrate" setting for the console - if we have a bad CRC, we don't 4597have any device yet where we could complain.] 4598 4599Note: once the monitor has been relocated, then it will complain if 4600the default environment is used; a new CRC is computed as soon as you 4601use the "saveenv" command to store a valid environment. 4602 4603- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4604 Echo the inverted Ethernet link state to the fault LED. 4605 4606 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4607 also needs to be defined. 4608 4609- CONFIG_SYS_FAULT_MII_ADDR: 4610 MII address of the PHY to check for the Ethernet link state. 4611 4612- CONFIG_NS16550_MIN_FUNCTIONS: 4613 Define this if you desire to only have use of the NS16550_init 4614 and NS16550_putc functions for the serial driver located at 4615 drivers/serial/ns16550.c. This option is useful for saving 4616 space for already greatly restricted images, including but not 4617 limited to NAND_SPL configurations. 4618 4619- CONFIG_DISPLAY_BOARDINFO 4620 Display information about the board that U-Boot is running on 4621 when U-Boot starts up. The board function checkboard() is called 4622 to do this. 4623 4624- CONFIG_DISPLAY_BOARDINFO_LATE 4625 Similar to the previous option, but display this information 4626 later, once stdio is running and output goes to the LCD, if 4627 present. 4628 4629- CONFIG_BOARD_SIZE_LIMIT: 4630 Maximum size of the U-Boot image. When defined, the 4631 build system checks that the actual size does not 4632 exceed it. 4633 4634Low Level (hardware related) configuration options: 4635--------------------------------------------------- 4636 4637- CONFIG_SYS_CACHELINE_SIZE: 4638 Cache Line Size of the CPU. 4639 4640- CONFIG_SYS_DEFAULT_IMMR: 4641 Default address of the IMMR after system reset. 4642 4643 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4644 and RPXsuper) to be able to adjust the position of 4645 the IMMR register after a reset. 4646 4647- CONFIG_SYS_CCSRBAR_DEFAULT: 4648 Default (power-on reset) physical address of CCSR on Freescale 4649 PowerPC SOCs. 4650 4651- CONFIG_SYS_CCSRBAR: 4652 Virtual address of CCSR. On a 32-bit build, this is typically 4653 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4654 4655 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4656 for cross-platform code that uses that macro instead. 4657 4658- CONFIG_SYS_CCSRBAR_PHYS: 4659 Physical address of CCSR. CCSR can be relocated to a new 4660 physical address, if desired. In this case, this macro should 4661 be set to that address. Otherwise, it should be set to the 4662 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4663 is typically relocated on 36-bit builds. It is recommended 4664 that this macro be defined via the _HIGH and _LOW macros: 4665 4666 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4667 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4668 4669- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4670 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4671 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4672 used in assembly code, so it must not contain typecasts or 4673 integer size suffixes (e.g. "ULL"). 4674 4675- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4676 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4677 used in assembly code, so it must not contain typecasts or 4678 integer size suffixes (e.g. "ULL"). 4679 4680- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4681 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4682 forced to a value that ensures that CCSR is not relocated. 4683 4684- Floppy Disk Support: 4685 CONFIG_SYS_FDC_DRIVE_NUMBER 4686 4687 the default drive number (default value 0) 4688 4689 CONFIG_SYS_ISA_IO_STRIDE 4690 4691 defines the spacing between FDC chipset registers 4692 (default value 1) 4693 4694 CONFIG_SYS_ISA_IO_OFFSET 4695 4696 defines the offset of register from address. It 4697 depends on which part of the data bus is connected to 4698 the FDC chipset. (default value 0) 4699 4700 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4701 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4702 default value. 4703 4704 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4705 fdc_hw_init() is called at the beginning of the FDC 4706 setup. fdc_hw_init() must be provided by the board 4707 source code. It is used to make hardware-dependent 4708 initializations. 4709 4710- CONFIG_IDE_AHB: 4711 Most IDE controllers were designed to be connected with PCI 4712 interface. Only few of them were designed for AHB interface. 4713 When software is doing ATA command and data transfer to 4714 IDE devices through IDE-AHB controller, some additional 4715 registers accessing to these kind of IDE-AHB controller 4716 is required. 4717 4718- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4719 DO NOT CHANGE unless you know exactly what you're 4720 doing! (11-4) [MPC8xx/82xx systems only] 4721 4722- CONFIG_SYS_INIT_RAM_ADDR: 4723 4724 Start address of memory area that can be used for 4725 initial data and stack; please note that this must be 4726 writable memory that is working WITHOUT special 4727 initialization, i. e. you CANNOT use normal RAM which 4728 will become available only after programming the 4729 memory controller and running certain initialization 4730 sequences. 4731 4732 U-Boot uses the following memory types: 4733 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4734 - MPC824X: data cache 4735 - PPC4xx: data cache 4736 4737- CONFIG_SYS_GBL_DATA_OFFSET: 4738 4739 Offset of the initial data structure in the memory 4740 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4741 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4742 data is located at the end of the available space 4743 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4744 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4745 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4746 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4747 4748 Note: 4749 On the MPC824X (or other systems that use the data 4750 cache for initial memory) the address chosen for 4751 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4752 point to an otherwise UNUSED address space between 4753 the top of RAM and the start of the PCI space. 4754 4755- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4756 4757- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4758 4759- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4760 4761- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4762 4763- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4764 4765- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4766 4767- CONFIG_SYS_OR_TIMING_SDRAM: 4768 SDRAM timing 4769 4770- CONFIG_SYS_MAMR_PTA: 4771 periodic timer for refresh 4772 4773- CONFIG_SYS_DER: Debug Event Register (37-47) 4774 4775- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4776 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4777 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4778 CONFIG_SYS_BR1_PRELIM: 4779 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4780 4781- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4782 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4783 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4784 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4785 4786- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4787 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4788 Machine Mode Register and Memory Periodic Timer 4789 Prescaler definitions (SDRAM timing) 4790 4791- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4792 enable I2C microcode relocation patch (MPC8xx); 4793 define relocation offset in DPRAM [DSP2] 4794 4795- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4796 enable SMC microcode relocation patch (MPC8xx); 4797 define relocation offset in DPRAM [SMC1] 4798 4799- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4800 enable SPI microcode relocation patch (MPC8xx); 4801 define relocation offset in DPRAM [SCC4] 4802 4803- CONFIG_SYS_USE_OSCCLK: 4804 Use OSCM clock mode on MBX8xx board. Be careful, 4805 wrong setting might damage your board. Read 4806 doc/README.MBX before setting this variable! 4807 4808- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4809 Offset of the bootmode word in DPRAM used by post 4810 (Power On Self Tests). This definition overrides 4811 #define'd default value in commproc.h resp. 4812 cpm_8260.h. 4813 4814- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4815 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4816 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4817 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4818 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4819 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4820 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4821 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4822 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4823 4824- CONFIG_PCI_DISABLE_PCIE: 4825 Disable PCI-Express on systems where it is supported but not 4826 required. 4827 4828- CONFIG_PCI_ENUM_ONLY 4829 Only scan through and get the devices on the buses. 4830 Don't do any setup work, presumably because someone or 4831 something has already done it, and we don't need to do it 4832 a second time. Useful for platforms that are pre-booted 4833 by coreboot or similar. 4834 4835- CONFIG_PCI_INDIRECT_BRIDGE: 4836 Enable support for indirect PCI bridges. 4837 4838- CONFIG_SYS_SRIO: 4839 Chip has SRIO or not 4840 4841- CONFIG_SRIO1: 4842 Board has SRIO 1 port available 4843 4844- CONFIG_SRIO2: 4845 Board has SRIO 2 port available 4846 4847- CONFIG_SRIO_PCIE_BOOT_MASTER 4848 Board can support master function for Boot from SRIO and PCIE 4849 4850- CONFIG_SYS_SRIOn_MEM_VIRT: 4851 Virtual Address of SRIO port 'n' memory region 4852 4853- CONFIG_SYS_SRIOn_MEM_PHYS: 4854 Physical Address of SRIO port 'n' memory region 4855 4856- CONFIG_SYS_SRIOn_MEM_SIZE: 4857 Size of SRIO port 'n' memory region 4858 4859- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4860 Defined to tell the NAND controller that the NAND chip is using 4861 a 16 bit bus. 4862 Not all NAND drivers use this symbol. 4863 Example of drivers that use it: 4864 - drivers/mtd/nand/ndfc.c 4865 - drivers/mtd/nand/mxc_nand.c 4866 4867- CONFIG_SYS_NDFC_EBC0_CFG 4868 Sets the EBC0_CFG register for the NDFC. If not defined 4869 a default value will be used. 4870 4871- CONFIG_SPD_EEPROM 4872 Get DDR timing information from an I2C EEPROM. Common 4873 with pluggable memory modules such as SODIMMs 4874 4875 SPD_EEPROM_ADDRESS 4876 I2C address of the SPD EEPROM 4877 4878- CONFIG_SYS_SPD_BUS_NUM 4879 If SPD EEPROM is on an I2C bus other than the first 4880 one, specify here. Note that the value must resolve 4881 to something your driver can deal with. 4882 4883- CONFIG_SYS_DDR_RAW_TIMING 4884 Get DDR timing information from other than SPD. Common with 4885 soldered DDR chips onboard without SPD. DDR raw timing 4886 parameters are extracted from datasheet and hard-coded into 4887 header files or board specific files. 4888 4889- CONFIG_FSL_DDR_INTERACTIVE 4890 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4891 4892- CONFIG_FSL_DDR_SYNC_REFRESH 4893 Enable sync of refresh for multiple controllers. 4894 4895- CONFIG_FSL_DDR_BIST 4896 Enable built-in memory test for Freescale DDR controllers. 4897 4898- CONFIG_SYS_83XX_DDR_USES_CS0 4899 Only for 83xx systems. If specified, then DDR should 4900 be configured using CS0 and CS1 instead of CS2 and CS3. 4901 4902- CONFIG_ETHER_ON_FEC[12] 4903 Define to enable FEC[12] on a 8xx series processor. 4904 4905- CONFIG_FEC[12]_PHY 4906 Define to the hardcoded PHY address which corresponds 4907 to the given FEC; i. e. 4908 #define CONFIG_FEC1_PHY 4 4909 means that the PHY with address 4 is connected to FEC1 4910 4911 When set to -1, means to probe for first available. 4912 4913- CONFIG_FEC[12]_PHY_NORXERR 4914 The PHY does not have a RXERR line (RMII only). 4915 (so program the FEC to ignore it). 4916 4917- CONFIG_RMII 4918 Enable RMII mode for all FECs. 4919 Note that this is a global option, we can't 4920 have one FEC in standard MII mode and another in RMII mode. 4921 4922- CONFIG_CRC32_VERIFY 4923 Add a verify option to the crc32 command. 4924 The syntax is: 4925 4926 => crc32 -v <address> <count> <crc32> 4927 4928 Where address/count indicate a memory area 4929 and crc32 is the correct crc32 which the 4930 area should have. 4931 4932- CONFIG_LOOPW 4933 Add the "loopw" memory command. This only takes effect if 4934 the memory commands are activated globally (CONFIG_CMD_MEM). 4935 4936- CONFIG_MX_CYCLIC 4937 Add the "mdc" and "mwc" memory commands. These are cyclic 4938 "md/mw" commands. 4939 Examples: 4940 4941 => mdc.b 10 4 500 4942 This command will print 4 bytes (10,11,12,13) each 500 ms. 4943 4944 => mwc.l 100 12345678 10 4945 This command will write 12345678 to address 100 all 10 ms. 4946 4947 This only takes effect if the memory commands are activated 4948 globally (CONFIG_CMD_MEM). 4949 4950- CONFIG_SKIP_LOWLEVEL_INIT 4951 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4952 low level initializations (like setting up the memory 4953 controller) are omitted and/or U-Boot does not 4954 relocate itself into RAM. 4955 4956 Normally this variable MUST NOT be defined. The only 4957 exception is when U-Boot is loaded (to RAM) by some 4958 other boot loader or by a debugger which performs 4959 these initializations itself. 4960 4961- CONFIG_SPL_BUILD 4962 Modifies the behaviour of start.S when compiling a loader 4963 that is executed before the actual U-Boot. E.g. when 4964 compiling a NAND SPL. 4965 4966- CONFIG_TPL_BUILD 4967 Modifies the behaviour of start.S when compiling a loader 4968 that is executed after the SPL and before the actual U-Boot. 4969 It is loaded by the SPL. 4970 4971- CONFIG_SYS_MPC85XX_NO_RESETVEC 4972 Only for 85xx systems. If this variable is specified, the section 4973 .resetvec is not kept and the section .bootpg is placed in the 4974 previous 4k of the .text section. 4975 4976- CONFIG_ARCH_MAP_SYSMEM 4977 Generally U-Boot (and in particular the md command) uses 4978 effective address. It is therefore not necessary to regard 4979 U-Boot address as virtual addresses that need to be translated 4980 to physical addresses. However, sandbox requires this, since 4981 it maintains its own little RAM buffer which contains all 4982 addressable memory. This option causes some memory accesses 4983 to be mapped through map_sysmem() / unmap_sysmem(). 4984 4985- CONFIG_USE_ARCH_MEMCPY 4986 CONFIG_USE_ARCH_MEMSET 4987 If these options are used a optimized version of memcpy/memset will 4988 be used if available. These functions may be faster under some 4989 conditions but may increase the binary size. 4990 4991- CONFIG_X86_RESET_VECTOR 4992 If defined, the x86 reset vector code is included. This is not 4993 needed when U-Boot is running from Coreboot. 4994 4995- CONFIG_SYS_MPUCLK 4996 Defines the MPU clock speed (in MHz). 4997 4998 NOTE : currently only supported on AM335x platforms. 4999 5000- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 5001 Enables the RTC32K OSC on AM33xx based plattforms 5002 5003- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 5004 Option to disable subpage write in NAND driver 5005 driver that uses this: 5006 drivers/mtd/nand/davinci_nand.c 5007 5008Freescale QE/FMAN Firmware Support: 5009----------------------------------- 5010 5011The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 5012loading of "firmware", which is encoded in the QE firmware binary format. 5013This firmware often needs to be loaded during U-Boot booting, so macros 5014are used to identify the storage device (NOR flash, SPI, etc) and the address 5015within that device. 5016 5017- CONFIG_SYS_FMAN_FW_ADDR 5018 The address in the storage device where the FMAN microcode is located. The 5019 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 5020 is also specified. 5021 5022- CONFIG_SYS_QE_FW_ADDR 5023 The address in the storage device where the QE microcode is located. The 5024 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 5025 is also specified. 5026 5027- CONFIG_SYS_QE_FMAN_FW_LENGTH 5028 The maximum possible size of the firmware. The firmware binary format 5029 has a field that specifies the actual size of the firmware, but it 5030 might not be possible to read any part of the firmware unless some 5031 local storage is allocated to hold the entire firmware first. 5032 5033- CONFIG_SYS_QE_FMAN_FW_IN_NOR 5034 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 5035 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 5036 virtual address in NOR flash. 5037 5038- CONFIG_SYS_QE_FMAN_FW_IN_NAND 5039 Specifies that QE/FMAN firmware is located in NAND flash. 5040 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 5041 5042- CONFIG_SYS_QE_FMAN_FW_IN_MMC 5043 Specifies that QE/FMAN firmware is located on the primary SD/MMC 5044 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5045 5046- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 5047 Specifies that QE/FMAN firmware is located on the primary SPI 5048 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5049 5050- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 5051 Specifies that QE/FMAN firmware is located in the remote (master) 5052 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 5053 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 5054 window->master inbound window->master LAW->the ucode address in 5055 master's memory space. 5056 5057Freescale Layerscape Management Complex Firmware Support: 5058--------------------------------------------------------- 5059The Freescale Layerscape Management Complex (MC) supports the loading of 5060"firmware". 5061This firmware often needs to be loaded during U-Boot booting, so macros 5062are used to identify the storage device (NOR flash, SPI, etc) and the address 5063within that device. 5064 5065- CONFIG_FSL_MC_ENET 5066 Enable the MC driver for Layerscape SoCs. 5067 5068- CONFIG_SYS_LS_MC_FW_ADDR 5069 The address in the storage device where the firmware is located. The 5070 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro 5071 is also specified. 5072 5073- CONFIG_SYS_LS_MC_FW_LENGTH 5074 The maximum possible size of the firmware. The firmware binary format 5075 has a field that specifies the actual size of the firmware, but it 5076 might not be possible to read any part of the firmware unless some 5077 local storage is allocated to hold the entire firmware first. 5078 5079- CONFIG_SYS_LS_MC_FW_IN_NOR 5080 Specifies that MC firmware is located in NOR flash, mapped as 5081 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the 5082 virtual address in NOR flash. 5083 5084Building the Software: 5085====================== 5086 5087Building U-Boot has been tested in several native build environments 5088and in many different cross environments. Of course we cannot support 5089all possibly existing versions of cross development tools in all 5090(potentially obsolete) versions. In case of tool chain problems we 5091recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 5092which is extensively used to build and test U-Boot. 5093 5094If you are not using a native environment, it is assumed that you 5095have GNU cross compiling tools available in your path. In this case, 5096you must set the environment variable CROSS_COMPILE in your shell. 5097Note that no changes to the Makefile or any other source files are 5098necessary. For example using the ELDK on a 4xx CPU, please enter: 5099 5100 $ CROSS_COMPILE=ppc_4xx- 5101 $ export CROSS_COMPILE 5102 5103Note: If you wish to generate Windows versions of the utilities in 5104 the tools directory you can use the MinGW toolchain 5105 (http://www.mingw.org). Set your HOST tools to the MinGW 5106 toolchain and execute 'make tools'. For example: 5107 5108 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 5109 5110 Binaries such as tools/mkimage.exe will be created which can 5111 be executed on computers running Windows. 5112 5113U-Boot is intended to be simple to build. After installing the 5114sources you must configure U-Boot for one specific board type. This 5115is done by typing: 5116 5117 make NAME_defconfig 5118 5119where "NAME_defconfig" is the name of one of the existing configu- 5120rations; see boards.cfg for supported names. 5121 5122Note: for some board special configuration names may exist; check if 5123 additional information is available from the board vendor; for 5124 instance, the TQM823L systems are available without (standard) 5125 or with LCD support. You can select such additional "features" 5126 when choosing the configuration, i. e. 5127 5128 make TQM823L_defconfig 5129 - will configure for a plain TQM823L, i. e. no LCD support 5130 5131 make TQM823L_LCD_defconfig 5132 - will configure for a TQM823L with U-Boot console on LCD 5133 5134 etc. 5135 5136 5137Finally, type "make all", and you should get some working U-Boot 5138images ready for download to / installation on your system: 5139 5140- "u-boot.bin" is a raw binary image 5141- "u-boot" is an image in ELF binary format 5142- "u-boot.srec" is in Motorola S-Record format 5143 5144By default the build is performed locally and the objects are saved 5145in the source directory. One of the two methods can be used to change 5146this behavior and build U-Boot to some external directory: 5147 51481. Add O= to the make command line invocations: 5149 5150 make O=/tmp/build distclean 5151 make O=/tmp/build NAME_defconfig 5152 make O=/tmp/build all 5153 51542. Set environment variable KBUILD_OUTPUT to point to the desired location: 5155 5156 export KBUILD_OUTPUT=/tmp/build 5157 make distclean 5158 make NAME_defconfig 5159 make all 5160 5161Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 5162variable. 5163 5164 5165Please be aware that the Makefiles assume you are using GNU make, so 5166for instance on NetBSD you might need to use "gmake" instead of 5167native "make". 5168 5169 5170If the system board that you have is not listed, then you will need 5171to port U-Boot to your hardware platform. To do this, follow these 5172steps: 5173 51741. Add a new configuration option for your board to the toplevel 5175 "boards.cfg" file, using the existing entries as examples. 5176 Follow the instructions there to keep the boards in order. 51772. Create a new directory to hold your board specific code. Add any 5178 files you need. In your board directory, you will need at least 5179 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 51803. Create a new configuration file "include/configs/<board>.h" for 5181 your board 51823. If you're porting U-Boot to a new CPU, then also create a new 5183 directory to hold your CPU specific code. Add any files you need. 51844. Run "make <board>_defconfig" with your new name. 51855. Type "make", and you should get a working "u-boot.srec" file 5186 to be installed on your target system. 51876. Debug and solve any problems that might arise. 5188 [Of course, this last step is much harder than it sounds.] 5189 5190 5191Testing of U-Boot Modifications, Ports to New Hardware, etc.: 5192============================================================== 5193 5194If you have modified U-Boot sources (for instance added a new board 5195or support for new devices, a new CPU, etc.) you are expected to 5196provide feedback to the other developers. The feedback normally takes 5197the form of a "patch", i. e. a context diff against a certain (latest 5198official or latest in the git repository) version of U-Boot sources. 5199 5200But before you submit such a patch, please verify that your modifi- 5201cation did not break existing code. At least make sure that *ALL* of 5202the supported boards compile WITHOUT ANY compiler warnings. To do so, 5203just run the "MAKEALL" script, which will configure and build U-Boot 5204for ALL supported system. Be warned, this will take a while. You can 5205select which (cross) compiler to use by passing a `CROSS_COMPILE' 5206environment variable to the script, i. e. to use the ELDK cross tools 5207you can type 5208 5209 CROSS_COMPILE=ppc_8xx- MAKEALL 5210 5211or to build on a native PowerPC system you can type 5212 5213 CROSS_COMPILE=' ' MAKEALL 5214 5215When using the MAKEALL script, the default behaviour is to build 5216U-Boot in the source directory. This location can be changed by 5217setting the BUILD_DIR environment variable. Also, for each target 5218built, the MAKEALL script saves two log files (<target>.ERR and 5219<target>.MAKEALL) in the <source dir>/LOG directory. This default 5220location can be changed by setting the MAKEALL_LOGDIR environment 5221variable. For example: 5222 5223 export BUILD_DIR=/tmp/build 5224 export MAKEALL_LOGDIR=/tmp/log 5225 CROSS_COMPILE=ppc_8xx- MAKEALL 5226 5227With the above settings build objects are saved in the /tmp/build, 5228log files are saved in the /tmp/log and the source tree remains clean 5229during the whole build process. 5230 5231 5232See also "U-Boot Porting Guide" below. 5233 5234 5235Monitor Commands - Overview: 5236============================ 5237 5238go - start application at address 'addr' 5239run - run commands in an environment variable 5240bootm - boot application image from memory 5241bootp - boot image via network using BootP/TFTP protocol 5242bootz - boot zImage from memory 5243tftpboot- boot image via network using TFTP protocol 5244 and env variables "ipaddr" and "serverip" 5245 (and eventually "gatewayip") 5246tftpput - upload a file via network using TFTP protocol 5247rarpboot- boot image via network using RARP/TFTP protocol 5248diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 5249loads - load S-Record file over serial line 5250loadb - load binary file over serial line (kermit mode) 5251md - memory display 5252mm - memory modify (auto-incrementing) 5253nm - memory modify (constant address) 5254mw - memory write (fill) 5255cp - memory copy 5256cmp - memory compare 5257crc32 - checksum calculation 5258i2c - I2C sub-system 5259sspi - SPI utility commands 5260base - print or set address offset 5261printenv- print environment variables 5262setenv - set environment variables 5263saveenv - save environment variables to persistent storage 5264protect - enable or disable FLASH write protection 5265erase - erase FLASH memory 5266flinfo - print FLASH memory information 5267nand - NAND memory operations (see doc/README.nand) 5268bdinfo - print Board Info structure 5269iminfo - print header information for application image 5270coninfo - print console devices and informations 5271ide - IDE sub-system 5272loop - infinite loop on address range 5273loopw - infinite write loop on address range 5274mtest - simple RAM test 5275icache - enable or disable instruction cache 5276dcache - enable or disable data cache 5277reset - Perform RESET of the CPU 5278echo - echo args to console 5279version - print monitor version 5280help - print online help 5281? - alias for 'help' 5282 5283 5284Monitor Commands - Detailed Description: 5285======================================== 5286 5287TODO. 5288 5289For now: just type "help <command>". 5290 5291 5292Environment Variables: 5293====================== 5294 5295U-Boot supports user configuration using Environment Variables which 5296can be made persistent by saving to Flash memory. 5297 5298Environment Variables are set using "setenv", printed using 5299"printenv", and saved to Flash using "saveenv". Using "setenv" 5300without a value can be used to delete a variable from the 5301environment. As long as you don't save the environment you are 5302working with an in-memory copy. In case the Flash area containing the 5303environment is erased by accident, a default environment is provided. 5304 5305Some configuration options can be set using Environment Variables. 5306 5307List of environment variables (most likely not complete): 5308 5309 baudrate - see CONFIG_BAUDRATE 5310 5311 bootdelay - see CONFIG_BOOTDELAY 5312 5313 bootcmd - see CONFIG_BOOTCOMMAND 5314 5315 bootargs - Boot arguments when booting an RTOS image 5316 5317 bootfile - Name of the image to load with TFTP 5318 5319 bootm_low - Memory range available for image processing in the bootm 5320 command can be restricted. This variable is given as 5321 a hexadecimal number and defines lowest address allowed 5322 for use by the bootm command. See also "bootm_size" 5323 environment variable. Address defined by "bootm_low" is 5324 also the base of the initial memory mapping for the Linux 5325 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 5326 bootm_mapsize. 5327 5328 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 5329 This variable is given as a hexadecimal number and it 5330 defines the size of the memory region starting at base 5331 address bootm_low that is accessible by the Linux kernel 5332 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 5333 as the default value if it is defined, and bootm_size is 5334 used otherwise. 5335 5336 bootm_size - Memory range available for image processing in the bootm 5337 command can be restricted. This variable is given as 5338 a hexadecimal number and defines the size of the region 5339 allowed for use by the bootm command. See also "bootm_low" 5340 environment variable. 5341 5342 updatefile - Location of the software update file on a TFTP server, used 5343 by the automatic software update feature. Please refer to 5344 documentation in doc/README.update for more details. 5345 5346 autoload - if set to "no" (any string beginning with 'n'), 5347 "bootp" will just load perform a lookup of the 5348 configuration from the BOOTP server, but not try to 5349 load any image using TFTP 5350 5351 autostart - if set to "yes", an image loaded using the "bootp", 5352 "rarpboot", "tftpboot" or "diskboot" commands will 5353 be automatically started (by internally calling 5354 "bootm") 5355 5356 If set to "no", a standalone image passed to the 5357 "bootm" command will be copied to the load address 5358 (and eventually uncompressed), but NOT be started. 5359 This can be used to load and uncompress arbitrary 5360 data. 5361 5362 fdt_high - if set this restricts the maximum address that the 5363 flattened device tree will be copied into upon boot. 5364 For example, if you have a system with 1 GB memory 5365 at physical address 0x10000000, while Linux kernel 5366 only recognizes the first 704 MB as low memory, you 5367 may need to set fdt_high as 0x3C000000 to have the 5368 device tree blob be copied to the maximum address 5369 of the 704 MB low memory, so that Linux kernel can 5370 access it during the boot procedure. 5371 5372 If this is set to the special value 0xFFFFFFFF then 5373 the fdt will not be copied at all on boot. For this 5374 to work it must reside in writable memory, have 5375 sufficient padding on the end of it for u-boot to 5376 add the information it needs into it, and the memory 5377 must be accessible by the kernel. 5378 5379 fdtcontroladdr- if set this is the address of the control flattened 5380 device tree used by U-Boot when CONFIG_OF_CONTROL is 5381 defined. 5382 5383 i2cfast - (PPC405GP|PPC405EP only) 5384 if set to 'y' configures Linux I2C driver for fast 5385 mode (400kHZ). This environment variable is used in 5386 initialization code. So, for changes to be effective 5387 it must be saved and board must be reset. 5388 5389 initrd_high - restrict positioning of initrd images: 5390 If this variable is not set, initrd images will be 5391 copied to the highest possible address in RAM; this 5392 is usually what you want since it allows for 5393 maximum initrd size. If for some reason you want to 5394 make sure that the initrd image is loaded below the 5395 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 5396 variable to a value of "no" or "off" or "0". 5397 Alternatively, you can set it to a maximum upper 5398 address to use (U-Boot will still check that it 5399 does not overwrite the U-Boot stack and data). 5400 5401 For instance, when you have a system with 16 MB 5402 RAM, and want to reserve 4 MB from use by Linux, 5403 you can do this by adding "mem=12M" to the value of 5404 the "bootargs" variable. However, now you must make 5405 sure that the initrd image is placed in the first 5406 12 MB as well - this can be done with 5407 5408 setenv initrd_high 00c00000 5409 5410 If you set initrd_high to 0xFFFFFFFF, this is an 5411 indication to U-Boot that all addresses are legal 5412 for the Linux kernel, including addresses in flash 5413 memory. In this case U-Boot will NOT COPY the 5414 ramdisk at all. This may be useful to reduce the 5415 boot time on your system, but requires that this 5416 feature is supported by your Linux kernel. 5417 5418 ipaddr - IP address; needed for tftpboot command 5419 5420 loadaddr - Default load address for commands like "bootp", 5421 "rarpboot", "tftpboot", "loadb" or "diskboot" 5422 5423 loads_echo - see CONFIG_LOADS_ECHO 5424 5425 serverip - TFTP server IP address; needed for tftpboot command 5426 5427 bootretry - see CONFIG_BOOT_RETRY_TIME 5428 5429 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 5430 5431 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 5432 5433 ethprime - controls which interface is used first. 5434 5435 ethact - controls which interface is currently active. 5436 For example you can do the following 5437 5438 => setenv ethact FEC 5439 => ping 192.168.0.1 # traffic sent on FEC 5440 => setenv ethact SCC 5441 => ping 10.0.0.1 # traffic sent on SCC 5442 5443 ethrotate - When set to "no" U-Boot does not go through all 5444 available network interfaces. 5445 It just stays at the currently selected interface. 5446 5447 netretry - When set to "no" each network operation will 5448 either succeed or fail without retrying. 5449 When set to "once" the network operation will 5450 fail when all the available network interfaces 5451 are tried once without success. 5452 Useful on scripts which control the retry operation 5453 themselves. 5454 5455 npe_ucode - set load address for the NPE microcode 5456 5457 silent_linux - If set then Linux will be told to boot silently, by 5458 changing the console to be empty. If "yes" it will be 5459 made silent. If "no" it will not be made silent. If 5460 unset, then it will be made silent if the U-Boot console 5461 is silent. 5462 5463 tftpsrcport - If this is set, the value is used for TFTP's 5464 UDP source port. 5465 5466 tftpdstport - If this is set, the value is used for TFTP's UDP 5467 destination port instead of the Well Know Port 69. 5468 5469 tftpblocksize - Block size to use for TFTP transfers; if not set, 5470 we use the TFTP server's default block size 5471 5472 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5473 seconds, minimum value is 1000 = 1 second). Defines 5474 when a packet is considered to be lost so it has to 5475 be retransmitted. The default is 5000 = 5 seconds. 5476 Lowering this value may make downloads succeed 5477 faster in networks with high packet loss rates or 5478 with unreliable TFTP servers. 5479 5480 vlan - When set to a value < 4095 the traffic over 5481 Ethernet is encapsulated/received over 802.1q 5482 VLAN tagged frames. 5483 5484The following image location variables contain the location of images 5485used in booting. The "Image" column gives the role of the image and is 5486not an environment variable name. The other columns are environment 5487variable names. "File Name" gives the name of the file on a TFTP 5488server, "RAM Address" gives the location in RAM the image will be 5489loaded to, and "Flash Location" gives the image's address in NOR 5490flash or offset in NAND flash. 5491 5492*Note* - these variables don't have to be defined for all boards, some 5493boards currenlty use other variables for these purposes, and some 5494boards use these variables for other purposes. 5495 5496Image File Name RAM Address Flash Location 5497----- --------- ----------- -------------- 5498u-boot u-boot u-boot_addr_r u-boot_addr 5499Linux kernel bootfile kernel_addr_r kernel_addr 5500device tree blob fdtfile fdt_addr_r fdt_addr 5501ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5502 5503The following environment variables may be used and automatically 5504updated by the network boot commands ("bootp" and "rarpboot"), 5505depending the information provided by your boot server: 5506 5507 bootfile - see above 5508 dnsip - IP address of your Domain Name Server 5509 dnsip2 - IP address of your secondary Domain Name Server 5510 gatewayip - IP address of the Gateway (Router) to use 5511 hostname - Target hostname 5512 ipaddr - see above 5513 netmask - Subnet Mask 5514 rootpath - Pathname of the root filesystem on the NFS server 5515 serverip - see above 5516 5517 5518There are two special Environment Variables: 5519 5520 serial# - contains hardware identification information such 5521 as type string and/or serial number 5522 ethaddr - Ethernet address 5523 5524These variables can be set only once (usually during manufacturing of 5525the board). U-Boot refuses to delete or overwrite these variables 5526once they have been set once. 5527 5528 5529Further special Environment Variables: 5530 5531 ver - Contains the U-Boot version string as printed 5532 with the "version" command. This variable is 5533 readonly (see CONFIG_VERSION_VARIABLE). 5534 5535 5536Please note that changes to some configuration parameters may take 5537only effect after the next boot (yes, that's just like Windoze :-). 5538 5539 5540Callback functions for environment variables: 5541--------------------------------------------- 5542 5543For some environment variables, the behavior of u-boot needs to change 5544when their values are changed. This functionality allows functions to 5545be associated with arbitrary variables. On creation, overwrite, or 5546deletion, the callback will provide the opportunity for some side 5547effect to happen or for the change to be rejected. 5548 5549The callbacks are named and associated with a function using the 5550U_BOOT_ENV_CALLBACK macro in your board or driver code. 5551 5552These callbacks are associated with variables in one of two ways. The 5553static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5554in the board configuration to a string that defines a list of 5555associations. The list must be in the following format: 5556 5557 entry = variable_name[:callback_name] 5558 list = entry[,list] 5559 5560If the callback name is not specified, then the callback is deleted. 5561Spaces are also allowed anywhere in the list. 5562 5563Callbacks can also be associated by defining the ".callbacks" variable 5564with the same list format above. Any association in ".callbacks" will 5565override any association in the static list. You can define 5566CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5567".callbacks" environment variable in the default or embedded environment. 5568 5569 5570Command Line Parsing: 5571===================== 5572 5573There are two different command line parsers available with U-Boot: 5574the old "simple" one, and the much more powerful "hush" shell: 5575 5576Old, simple command line parser: 5577-------------------------------- 5578 5579- supports environment variables (through setenv / saveenv commands) 5580- several commands on one line, separated by ';' 5581- variable substitution using "... ${name} ..." syntax 5582- special characters ('$', ';') can be escaped by prefixing with '\', 5583 for example: 5584 setenv bootcmd bootm \${address} 5585- You can also escape text by enclosing in single apostrophes, for example: 5586 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5587 5588Hush shell: 5589----------- 5590 5591- similar to Bourne shell, with control structures like 5592 if...then...else...fi, for...do...done; while...do...done, 5593 until...do...done, ... 5594- supports environment ("global") variables (through setenv / saveenv 5595 commands) and local shell variables (through standard shell syntax 5596 "name=value"); only environment variables can be used with "run" 5597 command 5598 5599General rules: 5600-------------- 5601 5602(1) If a command line (or an environment variable executed by a "run" 5603 command) contains several commands separated by semicolon, and 5604 one of these commands fails, then the remaining commands will be 5605 executed anyway. 5606 5607(2) If you execute several variables with one call to run (i. e. 5608 calling run with a list of variables as arguments), any failing 5609 command will cause "run" to terminate, i. e. the remaining 5610 variables are not executed. 5611 5612Note for Redundant Ethernet Interfaces: 5613======================================= 5614 5615Some boards come with redundant Ethernet interfaces; U-Boot supports 5616such configurations and is capable of automatic selection of a 5617"working" interface when needed. MAC assignment works as follows: 5618 5619Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5620MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5621"eth1addr" (=>eth1), "eth2addr", ... 5622 5623If the network interface stores some valid MAC address (for instance 5624in SROM), this is used as default address if there is NO correspon- 5625ding setting in the environment; if the corresponding environment 5626variable is set, this overrides the settings in the card; that means: 5627 5628o If the SROM has a valid MAC address, and there is no address in the 5629 environment, the SROM's address is used. 5630 5631o If there is no valid address in the SROM, and a definition in the 5632 environment exists, then the value from the environment variable is 5633 used. 5634 5635o If both the SROM and the environment contain a MAC address, and 5636 both addresses are the same, this MAC address is used. 5637 5638o If both the SROM and the environment contain a MAC address, and the 5639 addresses differ, the value from the environment is used and a 5640 warning is printed. 5641 5642o If neither SROM nor the environment contain a MAC address, an error 5643 is raised. 5644 5645If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5646will be programmed into hardware as part of the initialization process. This 5647may be skipped by setting the appropriate 'ethmacskip' environment variable. 5648The naming convention is as follows: 5649"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5650 5651Image Formats: 5652============== 5653 5654U-Boot is capable of booting (and performing other auxiliary operations on) 5655images in two formats: 5656 5657New uImage format (FIT) 5658----------------------- 5659 5660Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5661to Flattened Device Tree). It allows the use of images with multiple 5662components (several kernels, ramdisks, etc.), with contents protected by 5663SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5664 5665 5666Old uImage format 5667----------------- 5668 5669Old image format is based on binary files which can be basically anything, 5670preceded by a special header; see the definitions in include/image.h for 5671details; basically, the header defines the following image properties: 5672 5673* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5674 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5675 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5676 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5677 INTEGRITY). 5678* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5679 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5680 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5681* Compression Type (uncompressed, gzip, bzip2) 5682* Load Address 5683* Entry Point 5684* Image Name 5685* Image Timestamp 5686 5687The header is marked by a special Magic Number, and both the header 5688and the data portions of the image are secured against corruption by 5689CRC32 checksums. 5690 5691 5692Linux Support: 5693============== 5694 5695Although U-Boot should support any OS or standalone application 5696easily, the main focus has always been on Linux during the design of 5697U-Boot. 5698 5699U-Boot includes many features that so far have been part of some 5700special "boot loader" code within the Linux kernel. Also, any 5701"initrd" images to be used are no longer part of one big Linux image; 5702instead, kernel and "initrd" are separate images. This implementation 5703serves several purposes: 5704 5705- the same features can be used for other OS or standalone 5706 applications (for instance: using compressed images to reduce the 5707 Flash memory footprint) 5708 5709- it becomes much easier to port new Linux kernel versions because 5710 lots of low-level, hardware dependent stuff are done by U-Boot 5711 5712- the same Linux kernel image can now be used with different "initrd" 5713 images; of course this also means that different kernel images can 5714 be run with the same "initrd". This makes testing easier (you don't 5715 have to build a new "zImage.initrd" Linux image when you just 5716 change a file in your "initrd"). Also, a field-upgrade of the 5717 software is easier now. 5718 5719 5720Linux HOWTO: 5721============ 5722 5723Porting Linux to U-Boot based systems: 5724--------------------------------------- 5725 5726U-Boot cannot save you from doing all the necessary modifications to 5727configure the Linux device drivers for use with your target hardware 5728(no, we don't intend to provide a full virtual machine interface to 5729Linux :-). 5730 5731But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5732 5733Just make sure your machine specific header file (for instance 5734include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5735Information structure as we define in include/asm-<arch>/u-boot.h, 5736and make sure that your definition of IMAP_ADDR uses the same value 5737as your U-Boot configuration in CONFIG_SYS_IMMR. 5738 5739Note that U-Boot now has a driver model, a unified model for drivers. 5740If you are adding a new driver, plumb it into driver model. If there 5741is no uclass available, you are encouraged to create one. See 5742doc/driver-model. 5743 5744 5745Configuring the Linux kernel: 5746----------------------------- 5747 5748No specific requirements for U-Boot. Make sure you have some root 5749device (initial ramdisk, NFS) for your target system. 5750 5751 5752Building a Linux Image: 5753----------------------- 5754 5755With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5756not used. If you use recent kernel source, a new build target 5757"uImage" will exist which automatically builds an image usable by 5758U-Boot. Most older kernels also have support for a "pImage" target, 5759which was introduced for our predecessor project PPCBoot and uses a 5760100% compatible format. 5761 5762Example: 5763 5764 make TQM850L_defconfig 5765 make oldconfig 5766 make dep 5767 make uImage 5768 5769The "uImage" build target uses a special tool (in 'tools/mkimage') to 5770encapsulate a compressed Linux kernel image with header information, 5771CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5772 5773* build a standard "vmlinux" kernel image (in ELF binary format): 5774 5775* convert the kernel into a raw binary image: 5776 5777 ${CROSS_COMPILE}-objcopy -O binary \ 5778 -R .note -R .comment \ 5779 -S vmlinux linux.bin 5780 5781* compress the binary image: 5782 5783 gzip -9 linux.bin 5784 5785* package compressed binary image for U-Boot: 5786 5787 mkimage -A ppc -O linux -T kernel -C gzip \ 5788 -a 0 -e 0 -n "Linux Kernel Image" \ 5789 -d linux.bin.gz uImage 5790 5791 5792The "mkimage" tool can also be used to create ramdisk images for use 5793with U-Boot, either separated from the Linux kernel image, or 5794combined into one file. "mkimage" encapsulates the images with a 64 5795byte header containing information about target architecture, 5796operating system, image type, compression method, entry points, time 5797stamp, CRC32 checksums, etc. 5798 5799"mkimage" can be called in two ways: to verify existing images and 5800print the header information, or to build new images. 5801 5802In the first form (with "-l" option) mkimage lists the information 5803contained in the header of an existing U-Boot image; this includes 5804checksum verification: 5805 5806 tools/mkimage -l image 5807 -l ==> list image header information 5808 5809The second form (with "-d" option) is used to build a U-Boot image 5810from a "data file" which is used as image payload: 5811 5812 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5813 -n name -d data_file image 5814 -A ==> set architecture to 'arch' 5815 -O ==> set operating system to 'os' 5816 -T ==> set image type to 'type' 5817 -C ==> set compression type 'comp' 5818 -a ==> set load address to 'addr' (hex) 5819 -e ==> set entry point to 'ep' (hex) 5820 -n ==> set image name to 'name' 5821 -d ==> use image data from 'datafile' 5822 5823Right now, all Linux kernels for PowerPC systems use the same load 5824address (0x00000000), but the entry point address depends on the 5825kernel version: 5826 5827- 2.2.x kernels have the entry point at 0x0000000C, 5828- 2.3.x and later kernels have the entry point at 0x00000000. 5829 5830So a typical call to build a U-Boot image would read: 5831 5832 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5833 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5834 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5835 > examples/uImage.TQM850L 5836 Image Name: 2.4.4 kernel for TQM850L 5837 Created: Wed Jul 19 02:34:59 2000 5838 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5839 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5840 Load Address: 0x00000000 5841 Entry Point: 0x00000000 5842 5843To verify the contents of the image (or check for corruption): 5844 5845 -> tools/mkimage -l examples/uImage.TQM850L 5846 Image Name: 2.4.4 kernel for TQM850L 5847 Created: Wed Jul 19 02:34:59 2000 5848 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5849 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5850 Load Address: 0x00000000 5851 Entry Point: 0x00000000 5852 5853NOTE: for embedded systems where boot time is critical you can trade 5854speed for memory and install an UNCOMPRESSED image instead: this 5855needs more space in Flash, but boots much faster since it does not 5856need to be uncompressed: 5857 5858 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5859 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5860 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5861 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5862 > examples/uImage.TQM850L-uncompressed 5863 Image Name: 2.4.4 kernel for TQM850L 5864 Created: Wed Jul 19 02:34:59 2000 5865 Image Type: PowerPC Linux Kernel Image (uncompressed) 5866 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5867 Load Address: 0x00000000 5868 Entry Point: 0x00000000 5869 5870 5871Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5872when your kernel is intended to use an initial ramdisk: 5873 5874 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5875 > -A ppc -O linux -T ramdisk -C gzip \ 5876 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5877 Image Name: Simple Ramdisk Image 5878 Created: Wed Jan 12 14:01:50 2000 5879 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5880 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5881 Load Address: 0x00000000 5882 Entry Point: 0x00000000 5883 5884The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5885option performs the converse operation of the mkimage's second form (the "-d" 5886option). Given an image built by mkimage, the dumpimage extracts a "data file" 5887from the image: 5888 5889 tools/dumpimage -i image -T type -p position data_file 5890 -i ==> extract from the 'image' a specific 'data_file' 5891 -T ==> set image type to 'type' 5892 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5893 5894 5895Installing a Linux Image: 5896------------------------- 5897 5898To downloading a U-Boot image over the serial (console) interface, 5899you must convert the image to S-Record format: 5900 5901 objcopy -I binary -O srec examples/image examples/image.srec 5902 5903The 'objcopy' does not understand the information in the U-Boot 5904image header, so the resulting S-Record file will be relative to 5905address 0x00000000. To load it to a given address, you need to 5906specify the target address as 'offset' parameter with the 'loads' 5907command. 5908 5909Example: install the image to address 0x40100000 (which on the 5910TQM8xxL is in the first Flash bank): 5911 5912 => erase 40100000 401FFFFF 5913 5914 .......... done 5915 Erased 8 sectors 5916 5917 => loads 40100000 5918 ## Ready for S-Record download ... 5919 ~>examples/image.srec 5920 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5921 ... 5922 15989 15990 15991 15992 5923 [file transfer complete] 5924 [connected] 5925 ## Start Addr = 0x00000000 5926 5927 5928You can check the success of the download using the 'iminfo' command; 5929this includes a checksum verification so you can be sure no data 5930corruption happened: 5931 5932 => imi 40100000 5933 5934 ## Checking Image at 40100000 ... 5935 Image Name: 2.2.13 for initrd on TQM850L 5936 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5937 Data Size: 335725 Bytes = 327 kB = 0 MB 5938 Load Address: 00000000 5939 Entry Point: 0000000c 5940 Verifying Checksum ... OK 5941 5942 5943Boot Linux: 5944----------- 5945 5946The "bootm" command is used to boot an application that is stored in 5947memory (RAM or Flash). In case of a Linux kernel image, the contents 5948of the "bootargs" environment variable is passed to the kernel as 5949parameters. You can check and modify this variable using the 5950"printenv" and "setenv" commands: 5951 5952 5953 => printenv bootargs 5954 bootargs=root=/dev/ram 5955 5956 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5957 5958 => printenv bootargs 5959 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5960 5961 => bootm 40020000 5962 ## Booting Linux kernel at 40020000 ... 5963 Image Name: 2.2.13 for NFS on TQM850L 5964 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5965 Data Size: 381681 Bytes = 372 kB = 0 MB 5966 Load Address: 00000000 5967 Entry Point: 0000000c 5968 Verifying Checksum ... OK 5969 Uncompressing Kernel Image ... OK 5970 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 5971 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5972 time_init: decrementer frequency = 187500000/60 5973 Calibrating delay loop... 49.77 BogoMIPS 5974 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5975 ... 5976 5977If you want to boot a Linux kernel with initial RAM disk, you pass 5978the memory addresses of both the kernel and the initrd image (PPBCOOT 5979format!) to the "bootm" command: 5980 5981 => imi 40100000 40200000 5982 5983 ## Checking Image at 40100000 ... 5984 Image Name: 2.2.13 for initrd on TQM850L 5985 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5986 Data Size: 335725 Bytes = 327 kB = 0 MB 5987 Load Address: 00000000 5988 Entry Point: 0000000c 5989 Verifying Checksum ... OK 5990 5991 ## Checking Image at 40200000 ... 5992 Image Name: Simple Ramdisk Image 5993 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5994 Data Size: 566530 Bytes = 553 kB = 0 MB 5995 Load Address: 00000000 5996 Entry Point: 00000000 5997 Verifying Checksum ... OK 5998 5999 => bootm 40100000 40200000 6000 ## Booting Linux kernel at 40100000 ... 6001 Image Name: 2.2.13 for initrd on TQM850L 6002 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6003 Data Size: 335725 Bytes = 327 kB = 0 MB 6004 Load Address: 00000000 6005 Entry Point: 0000000c 6006 Verifying Checksum ... OK 6007 Uncompressing Kernel Image ... OK 6008 ## Loading RAMDisk Image at 40200000 ... 6009 Image Name: Simple Ramdisk Image 6010 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 6011 Data Size: 566530 Bytes = 553 kB = 0 MB 6012 Load Address: 00000000 6013 Entry Point: 00000000 6014 Verifying Checksum ... OK 6015 Loading Ramdisk ... OK 6016 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 6017 Boot arguments: root=/dev/ram 6018 time_init: decrementer frequency = 187500000/60 6019 Calibrating delay loop... 49.77 BogoMIPS 6020 ... 6021 RAMDISK: Compressed image found at block 0 6022 VFS: Mounted root (ext2 filesystem). 6023 6024 bash# 6025 6026Boot Linux and pass a flat device tree: 6027----------- 6028 6029First, U-Boot must be compiled with the appropriate defines. See the section 6030titled "Linux Kernel Interface" above for a more in depth explanation. The 6031following is an example of how to start a kernel and pass an updated 6032flat device tree: 6033 6034=> print oftaddr 6035oftaddr=0x300000 6036=> print oft 6037oft=oftrees/mpc8540ads.dtb 6038=> tftp $oftaddr $oft 6039Speed: 1000, full duplex 6040Using TSEC0 device 6041TFTP from server 192.168.1.1; our IP address is 192.168.1.101 6042Filename 'oftrees/mpc8540ads.dtb'. 6043Load address: 0x300000 6044Loading: # 6045done 6046Bytes transferred = 4106 (100a hex) 6047=> tftp $loadaddr $bootfile 6048Speed: 1000, full duplex 6049Using TSEC0 device 6050TFTP from server 192.168.1.1; our IP address is 192.168.1.2 6051Filename 'uImage'. 6052Load address: 0x200000 6053Loading:############ 6054done 6055Bytes transferred = 1029407 (fb51f hex) 6056=> print loadaddr 6057loadaddr=200000 6058=> print oftaddr 6059oftaddr=0x300000 6060=> bootm $loadaddr - $oftaddr 6061## Booting image at 00200000 ... 6062 Image Name: Linux-2.6.17-dirty 6063 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6064 Data Size: 1029343 Bytes = 1005.2 kB 6065 Load Address: 00000000 6066 Entry Point: 00000000 6067 Verifying Checksum ... OK 6068 Uncompressing Kernel Image ... OK 6069Booting using flat device tree at 0x300000 6070Using MPC85xx ADS machine description 6071Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 6072[snip] 6073 6074 6075More About U-Boot Image Types: 6076------------------------------ 6077 6078U-Boot supports the following image types: 6079 6080 "Standalone Programs" are directly runnable in the environment 6081 provided by U-Boot; it is expected that (if they behave 6082 well) you can continue to work in U-Boot after return from 6083 the Standalone Program. 6084 "OS Kernel Images" are usually images of some Embedded OS which 6085 will take over control completely. Usually these programs 6086 will install their own set of exception handlers, device 6087 drivers, set up the MMU, etc. - this means, that you cannot 6088 expect to re-enter U-Boot except by resetting the CPU. 6089 "RAMDisk Images" are more or less just data blocks, and their 6090 parameters (address, size) are passed to an OS kernel that is 6091 being started. 6092 "Multi-File Images" contain several images, typically an OS 6093 (Linux) kernel image and one or more data images like 6094 RAMDisks. This construct is useful for instance when you want 6095 to boot over the network using BOOTP etc., where the boot 6096 server provides just a single image file, but you want to get 6097 for instance an OS kernel and a RAMDisk image. 6098 6099 "Multi-File Images" start with a list of image sizes, each 6100 image size (in bytes) specified by an "uint32_t" in network 6101 byte order. This list is terminated by an "(uint32_t)0". 6102 Immediately after the terminating 0 follow the images, one by 6103 one, all aligned on "uint32_t" boundaries (size rounded up to 6104 a multiple of 4 bytes). 6105 6106 "Firmware Images" are binary images containing firmware (like 6107 U-Boot or FPGA images) which usually will be programmed to 6108 flash memory. 6109 6110 "Script files" are command sequences that will be executed by 6111 U-Boot's command interpreter; this feature is especially 6112 useful when you configure U-Boot to use a real shell (hush) 6113 as command interpreter. 6114 6115Booting the Linux zImage: 6116------------------------- 6117 6118On some platforms, it's possible to boot Linux zImage. This is done 6119using the "bootz" command. The syntax of "bootz" command is the same 6120as the syntax of "bootm" command. 6121 6122Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 6123kernel with raw initrd images. The syntax is slightly different, the 6124address of the initrd must be augmented by it's size, in the following 6125format: "<initrd addres>:<initrd size>". 6126 6127 6128Standalone HOWTO: 6129================= 6130 6131One of the features of U-Boot is that you can dynamically load and 6132run "standalone" applications, which can use some resources of 6133U-Boot like console I/O functions or interrupt services. 6134 6135Two simple examples are included with the sources: 6136 6137"Hello World" Demo: 6138------------------- 6139 6140'examples/hello_world.c' contains a small "Hello World" Demo 6141application; it is automatically compiled when you build U-Boot. 6142It's configured to run at address 0x00040004, so you can play with it 6143like that: 6144 6145 => loads 6146 ## Ready for S-Record download ... 6147 ~>examples/hello_world.srec 6148 1 2 3 4 5 6 7 8 9 10 11 ... 6149 [file transfer complete] 6150 [connected] 6151 ## Start Addr = 0x00040004 6152 6153 => go 40004 Hello World! This is a test. 6154 ## Starting application at 0x00040004 ... 6155 Hello World 6156 argc = 7 6157 argv[0] = "40004" 6158 argv[1] = "Hello" 6159 argv[2] = "World!" 6160 argv[3] = "This" 6161 argv[4] = "is" 6162 argv[5] = "a" 6163 argv[6] = "test." 6164 argv[7] = "<NULL>" 6165 Hit any key to exit ... 6166 6167 ## Application terminated, rc = 0x0 6168 6169Another example, which demonstrates how to register a CPM interrupt 6170handler with the U-Boot code, can be found in 'examples/timer.c'. 6171Here, a CPM timer is set up to generate an interrupt every second. 6172The interrupt service routine is trivial, just printing a '.' 6173character, but this is just a demo program. The application can be 6174controlled by the following keys: 6175 6176 ? - print current values og the CPM Timer registers 6177 b - enable interrupts and start timer 6178 e - stop timer and disable interrupts 6179 q - quit application 6180 6181 => loads 6182 ## Ready for S-Record download ... 6183 ~>examples/timer.srec 6184 1 2 3 4 5 6 7 8 9 10 11 ... 6185 [file transfer complete] 6186 [connected] 6187 ## Start Addr = 0x00040004 6188 6189 => go 40004 6190 ## Starting application at 0x00040004 ... 6191 TIMERS=0xfff00980 6192 Using timer 1 6193 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 6194 6195Hit 'b': 6196 [q, b, e, ?] Set interval 1000000 us 6197 Enabling timer 6198Hit '?': 6199 [q, b, e, ?] ........ 6200 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 6201Hit '?': 6202 [q, b, e, ?] . 6203 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 6204Hit '?': 6205 [q, b, e, ?] . 6206 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 6207Hit '?': 6208 [q, b, e, ?] . 6209 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 6210Hit 'e': 6211 [q, b, e, ?] ...Stopping timer 6212Hit 'q': 6213 [q, b, e, ?] ## Application terminated, rc = 0x0 6214 6215 6216Minicom warning: 6217================ 6218 6219Over time, many people have reported problems when trying to use the 6220"minicom" terminal emulation program for serial download. I (wd) 6221consider minicom to be broken, and recommend not to use it. Under 6222Unix, I recommend to use C-Kermit for general purpose use (and 6223especially for kermit binary protocol download ("loadb" command), and 6224use "cu" for S-Record download ("loads" command). See 6225http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 6226for help with kermit. 6227 6228 6229Nevertheless, if you absolutely want to use it try adding this 6230configuration to your "File transfer protocols" section: 6231 6232 Name Program Name U/D FullScr IO-Red. Multi 6233 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 6234 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 6235 6236 6237NetBSD Notes: 6238============= 6239 6240Starting at version 0.9.2, U-Boot supports NetBSD both as host 6241(build U-Boot) and target system (boots NetBSD/mpc8xx). 6242 6243Building requires a cross environment; it is known to work on 6244NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 6245need gmake since the Makefiles are not compatible with BSD make). 6246Note that the cross-powerpc package does not install include files; 6247attempting to build U-Boot will fail because <machine/ansi.h> is 6248missing. This file has to be installed and patched manually: 6249 6250 # cd /usr/pkg/cross/powerpc-netbsd/include 6251 # mkdir powerpc 6252 # ln -s powerpc machine 6253 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 6254 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 6255 6256Native builds *don't* work due to incompatibilities between native 6257and U-Boot include files. 6258 6259Booting assumes that (the first part of) the image booted is a 6260stage-2 loader which in turn loads and then invokes the kernel 6261proper. Loader sources will eventually appear in the NetBSD source 6262tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 6263meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 6264 6265 6266Implementation Internals: 6267========================= 6268 6269The following is not intended to be a complete description of every 6270implementation detail. However, it should help to understand the 6271inner workings of U-Boot and make it easier to port it to custom 6272hardware. 6273 6274 6275Initial Stack, Global Data: 6276--------------------------- 6277 6278The implementation of U-Boot is complicated by the fact that U-Boot 6279starts running out of ROM (flash memory), usually without access to 6280system RAM (because the memory controller is not initialized yet). 6281This means that we don't have writable Data or BSS segments, and BSS 6282is not initialized as zero. To be able to get a C environment working 6283at all, we have to allocate at least a minimal stack. Implementation 6284options for this are defined and restricted by the CPU used: Some CPU 6285models provide on-chip memory (like the IMMR area on MPC8xx and 6286MPC826x processors), on others (parts of) the data cache can be 6287locked as (mis-) used as memory, etc. 6288 6289 Chris Hallinan posted a good summary of these issues to the 6290 U-Boot mailing list: 6291 6292 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 6293 From: "Chris Hallinan" <clh@net1plus.com> 6294 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 6295 ... 6296 6297 Correct me if I'm wrong, folks, but the way I understand it 6298 is this: Using DCACHE as initial RAM for Stack, etc, does not 6299 require any physical RAM backing up the cache. The cleverness 6300 is that the cache is being used as a temporary supply of 6301 necessary storage before the SDRAM controller is setup. It's 6302 beyond the scope of this list to explain the details, but you 6303 can see how this works by studying the cache architecture and 6304 operation in the architecture and processor-specific manuals. 6305 6306 OCM is On Chip Memory, which I believe the 405GP has 4K. It 6307 is another option for the system designer to use as an 6308 initial stack/RAM area prior to SDRAM being available. Either 6309 option should work for you. Using CS 4 should be fine if your 6310 board designers haven't used it for something that would 6311 cause you grief during the initial boot! It is frequently not 6312 used. 6313 6314 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 6315 with your processor/board/system design. The default value 6316 you will find in any recent u-boot distribution in 6317 walnut.h should work for you. I'd set it to a value larger 6318 than your SDRAM module. If you have a 64MB SDRAM module, set 6319 it above 400_0000. Just make sure your board has no resources 6320 that are supposed to respond to that address! That code in 6321 start.S has been around a while and should work as is when 6322 you get the config right. 6323 6324 -Chris Hallinan 6325 DS4.COM, Inc. 6326 6327It is essential to remember this, since it has some impact on the C 6328code for the initialization procedures: 6329 6330* Initialized global data (data segment) is read-only. Do not attempt 6331 to write it. 6332 6333* Do not use any uninitialized global data (or implicitly initialized 6334 as zero data - BSS segment) at all - this is undefined, initiali- 6335 zation is performed later (when relocating to RAM). 6336 6337* Stack space is very limited. Avoid big data buffers or things like 6338 that. 6339 6340Having only the stack as writable memory limits means we cannot use 6341normal global data to share information between the code. But it 6342turned out that the implementation of U-Boot can be greatly 6343simplified by making a global data structure (gd_t) available to all 6344functions. We could pass a pointer to this data as argument to _all_ 6345functions, but this would bloat the code. Instead we use a feature of 6346the GCC compiler (Global Register Variables) to share the data: we 6347place a pointer (gd) to the global data into a register which we 6348reserve for this purpose. 6349 6350When choosing a register for such a purpose we are restricted by the 6351relevant (E)ABI specifications for the current architecture, and by 6352GCC's implementation. 6353 6354For PowerPC, the following registers have specific use: 6355 R1: stack pointer 6356 R2: reserved for system use 6357 R3-R4: parameter passing and return values 6358 R5-R10: parameter passing 6359 R13: small data area pointer 6360 R30: GOT pointer 6361 R31: frame pointer 6362 6363 (U-Boot also uses R12 as internal GOT pointer. r12 6364 is a volatile register so r12 needs to be reset when 6365 going back and forth between asm and C) 6366 6367 ==> U-Boot will use R2 to hold a pointer to the global data 6368 6369 Note: on PPC, we could use a static initializer (since the 6370 address of the global data structure is known at compile time), 6371 but it turned out that reserving a register results in somewhat 6372 smaller code - although the code savings are not that big (on 6373 average for all boards 752 bytes for the whole U-Boot image, 6374 624 text + 127 data). 6375 6376On Blackfin, the normal C ABI (except for P3) is followed as documented here: 6377 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 6378 6379 ==> U-Boot will use P3 to hold a pointer to the global data 6380 6381On ARM, the following registers are used: 6382 6383 R0: function argument word/integer result 6384 R1-R3: function argument word 6385 R9: platform specific 6386 R10: stack limit (used only if stack checking is enabled) 6387 R11: argument (frame) pointer 6388 R12: temporary workspace 6389 R13: stack pointer 6390 R14: link register 6391 R15: program counter 6392 6393 ==> U-Boot will use R9 to hold a pointer to the global data 6394 6395 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 6396 6397On Nios II, the ABI is documented here: 6398 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 6399 6400 ==> U-Boot will use gp to hold a pointer to the global data 6401 6402 Note: on Nios II, we give "-G0" option to gcc and don't use gp 6403 to access small data sections, so gp is free. 6404 6405On NDS32, the following registers are used: 6406 6407 R0-R1: argument/return 6408 R2-R5: argument 6409 R15: temporary register for assembler 6410 R16: trampoline register 6411 R28: frame pointer (FP) 6412 R29: global pointer (GP) 6413 R30: link register (LP) 6414 R31: stack pointer (SP) 6415 PC: program counter (PC) 6416 6417 ==> U-Boot will use R10 to hold a pointer to the global data 6418 6419NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 6420or current versions of GCC may "optimize" the code too much. 6421 6422Memory Management: 6423------------------ 6424 6425U-Boot runs in system state and uses physical addresses, i.e. the 6426MMU is not used either for address mapping nor for memory protection. 6427 6428The available memory is mapped to fixed addresses using the memory 6429controller. In this process, a contiguous block is formed for each 6430memory type (Flash, SDRAM, SRAM), even when it consists of several 6431physical memory banks. 6432 6433U-Boot is installed in the first 128 kB of the first Flash bank (on 6434TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 6435booting and sizing and initializing DRAM, the code relocates itself 6436to the upper end of DRAM. Immediately below the U-Boot code some 6437memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 6438configuration setting]. Below that, a structure with global Board 6439Info data is placed, followed by the stack (growing downward). 6440 6441Additionally, some exception handler code is copied to the low 8 kB 6442of DRAM (0x00000000 ... 0x00001FFF). 6443 6444So a typical memory configuration with 16 MB of DRAM could look like 6445this: 6446 6447 0x0000 0000 Exception Vector code 6448 : 6449 0x0000 1FFF 6450 0x0000 2000 Free for Application Use 6451 : 6452 : 6453 6454 : 6455 : 6456 0x00FB FF20 Monitor Stack (Growing downward) 6457 0x00FB FFAC Board Info Data and permanent copy of global data 6458 0x00FC 0000 Malloc Arena 6459 : 6460 0x00FD FFFF 6461 0x00FE 0000 RAM Copy of Monitor Code 6462 ... eventually: LCD or video framebuffer 6463 ... eventually: pRAM (Protected RAM - unchanged by reset) 6464 0x00FF FFFF [End of RAM] 6465 6466 6467System Initialization: 6468---------------------- 6469 6470In the reset configuration, U-Boot starts at the reset entry point 6471(on most PowerPC systems at address 0x00000100). Because of the reset 6472configuration for CS0# this is a mirror of the on board Flash memory. 6473To be able to re-map memory U-Boot then jumps to its link address. 6474To be able to implement the initialization code in C, a (small!) 6475initial stack is set up in the internal Dual Ported RAM (in case CPUs 6476which provide such a feature like MPC8xx or MPC8260), or in a locked 6477part of the data cache. After that, U-Boot initializes the CPU core, 6478the caches and the SIU. 6479 6480Next, all (potentially) available memory banks are mapped using a 6481preliminary mapping. For example, we put them on 512 MB boundaries 6482(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6483on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6484programmed for SDRAM access. Using the temporary configuration, a 6485simple memory test is run that determines the size of the SDRAM 6486banks. 6487 6488When there is more than one SDRAM bank, and the banks are of 6489different size, the largest is mapped first. For equal size, the first 6490bank (CS2#) is mapped first. The first mapping is always for address 64910x00000000, with any additional banks following immediately to create 6492contiguous memory starting from 0. 6493 6494Then, the monitor installs itself at the upper end of the SDRAM area 6495and allocates memory for use by malloc() and for the global Board 6496Info data; also, the exception vector code is copied to the low RAM 6497pages, and the final stack is set up. 6498 6499Only after this relocation will you have a "normal" C environment; 6500until that you are restricted in several ways, mostly because you are 6501running from ROM, and because the code will have to be relocated to a 6502new address in RAM. 6503 6504 6505U-Boot Porting Guide: 6506---------------------- 6507 6508[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6509list, October 2002] 6510 6511 6512int main(int argc, char *argv[]) 6513{ 6514 sighandler_t no_more_time; 6515 6516 signal(SIGALRM, no_more_time); 6517 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6518 6519 if (available_money > available_manpower) { 6520 Pay consultant to port U-Boot; 6521 return 0; 6522 } 6523 6524 Download latest U-Boot source; 6525 6526 Subscribe to u-boot mailing list; 6527 6528 if (clueless) 6529 email("Hi, I am new to U-Boot, how do I get started?"); 6530 6531 while (learning) { 6532 Read the README file in the top level directory; 6533 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6534 Read applicable doc/*.README; 6535 Read the source, Luke; 6536 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6537 } 6538 6539 if (available_money > toLocalCurrency ($2500)) 6540 Buy a BDI3000; 6541 else 6542 Add a lot of aggravation and time; 6543 6544 if (a similar board exists) { /* hopefully... */ 6545 cp -a board/<similar> board/<myboard> 6546 cp include/configs/<similar>.h include/configs/<myboard>.h 6547 } else { 6548 Create your own board support subdirectory; 6549 Create your own board include/configs/<myboard>.h file; 6550 } 6551 Edit new board/<myboard> files 6552 Edit new include/configs/<myboard>.h 6553 6554 while (!accepted) { 6555 while (!running) { 6556 do { 6557 Add / modify source code; 6558 } until (compiles); 6559 Debug; 6560 if (clueless) 6561 email("Hi, I am having problems..."); 6562 } 6563 Send patch file to the U-Boot email list; 6564 if (reasonable critiques) 6565 Incorporate improvements from email list code review; 6566 else 6567 Defend code as written; 6568 } 6569 6570 return 0; 6571} 6572 6573void no_more_time (int sig) 6574{ 6575 hire_a_guru(); 6576} 6577 6578 6579Coding Standards: 6580----------------- 6581 6582All contributions to U-Boot should conform to the Linux kernel 6583coding style; see the file "Documentation/CodingStyle" and the script 6584"scripts/Lindent" in your Linux kernel source directory. 6585 6586Source files originating from a different project (for example the 6587MTD subsystem) are generally exempt from these guidelines and are not 6588reformatted to ease subsequent migration to newer versions of those 6589sources. 6590 6591Please note that U-Boot is implemented in C (and to some small parts in 6592Assembler); no C++ is used, so please do not use C++ style comments (//) 6593in your code. 6594 6595Please also stick to the following formatting rules: 6596- remove any trailing white space 6597- use TAB characters for indentation and vertical alignment, not spaces 6598- make sure NOT to use DOS '\r\n' line feeds 6599- do not add more than 2 consecutive empty lines to source files 6600- do not add trailing empty lines to source files 6601 6602Submissions which do not conform to the standards may be returned 6603with a request to reformat the changes. 6604 6605 6606Submitting Patches: 6607------------------- 6608 6609Since the number of patches for U-Boot is growing, we need to 6610establish some rules. Submissions which do not conform to these rules 6611may be rejected, even when they contain important and valuable stuff. 6612 6613Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6614 6615Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6616see http://lists.denx.de/mailman/listinfo/u-boot 6617 6618When you send a patch, please include the following information with 6619it: 6620 6621* For bug fixes: a description of the bug and how your patch fixes 6622 this bug. Please try to include a way of demonstrating that the 6623 patch actually fixes something. 6624 6625* For new features: a description of the feature and your 6626 implementation. 6627 6628* A CHANGELOG entry as plaintext (separate from the patch) 6629 6630* For major contributions, your entry to the CREDITS file 6631 6632* When you add support for a new board, don't forget to add a 6633 maintainer e-mail address to the boards.cfg file, too. 6634 6635* If your patch adds new configuration options, don't forget to 6636 document these in the README file. 6637 6638* The patch itself. If you are using git (which is *strongly* 6639 recommended) you can easily generate the patch using the 6640 "git format-patch". If you then use "git send-email" to send it to 6641 the U-Boot mailing list, you will avoid most of the common problems 6642 with some other mail clients. 6643 6644 If you cannot use git, use "diff -purN OLD NEW". If your version of 6645 diff does not support these options, then get the latest version of 6646 GNU diff. 6647 6648 The current directory when running this command shall be the parent 6649 directory of the U-Boot source tree (i. e. please make sure that 6650 your patch includes sufficient directory information for the 6651 affected files). 6652 6653 We prefer patches as plain text. MIME attachments are discouraged, 6654 and compressed attachments must not be used. 6655 6656* If one logical set of modifications affects or creates several 6657 files, all these changes shall be submitted in a SINGLE patch file. 6658 6659* Changesets that contain different, unrelated modifications shall be 6660 submitted as SEPARATE patches, one patch per changeset. 6661 6662 6663Notes: 6664 6665* Before sending the patch, run the MAKEALL script on your patched 6666 source tree and make sure that no errors or warnings are reported 6667 for any of the boards. 6668 6669* Keep your modifications to the necessary minimum: A patch 6670 containing several unrelated changes or arbitrary reformats will be 6671 returned with a request to re-formatting / split it. 6672 6673* If you modify existing code, make sure that your new code does not 6674 add to the memory footprint of the code ;-) Small is beautiful! 6675 When adding new features, these should compile conditionally only 6676 (using #ifdef), and the resulting code with the new feature 6677 disabled must not need more memory than the old code without your 6678 modification. 6679 6680* Remember that there is a size limit of 100 kB per message on the 6681 u-boot mailing list. Bigger patches will be moderated. If they are 6682 reasonable and not too big, they will be acknowledged. But patches 6683 bigger than the size limit should be avoided. 6684