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! 692 693 694- Linux Kernel Interface: 695 CONFIG_CLOCKS_IN_MHZ 696 697 U-Boot stores all clock information in Hz 698 internally. For binary compatibility with older Linux 699 kernels (which expect the clocks passed in the 700 bd_info data to be in MHz) the environment variable 701 "clocks_in_mhz" can be defined so that U-Boot 702 converts clock data to MHZ before passing it to the 703 Linux kernel. 704 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 705 "clocks_in_mhz=1" is automatically included in the 706 default environment. 707 708 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 709 710 When transferring memsize parameter to Linux, some versions 711 expect it to be in bytes, others in MB. 712 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 713 714 CONFIG_OF_LIBFDT 715 716 New kernel versions are expecting firmware settings to be 717 passed using flattened device trees (based on open firmware 718 concepts). 719 720 CONFIG_OF_LIBFDT 721 * New libfdt-based support 722 * Adds the "fdt" command 723 * The bootm command automatically updates the fdt 724 725 OF_CPU - The proper name of the cpus node (only required for 726 MPC512X and MPC5xxx based boards). 727 OF_SOC - The proper name of the soc node (only required for 728 MPC512X and MPC5xxx based boards). 729 OF_TBCLK - The timebase frequency. 730 OF_STDOUT_PATH - The path to the console device 731 732 boards with QUICC Engines require OF_QE to set UCC MAC 733 addresses 734 735 CONFIG_OF_BOARD_SETUP 736 737 Board code has addition modification that it wants to make 738 to the flat device tree before handing it off to the kernel 739 740 CONFIG_OF_SYSTEM_SETUP 741 742 Other code has addition modification that it wants to make 743 to the flat device tree before handing it off to the kernel. 744 This causes ft_system_setup() to be called before booting 745 the kernel. 746 747 CONFIG_OF_BOOT_CPU 748 749 This define fills in the correct boot CPU in the boot 750 param header, the default value is zero if undefined. 751 752 CONFIG_OF_IDE_FIXUP 753 754 U-Boot can detect if an IDE device is present or not. 755 If not, and this new config option is activated, U-Boot 756 removes the ATA node from the DTS before booting Linux, 757 so the Linux IDE driver does not probe the device and 758 crash. This is needed for buggy hardware (uc101) where 759 no pull down resistor is connected to the signal IDE5V_DD7. 760 761 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 762 763 This setting is mandatory for all boards that have only one 764 machine type and must be used to specify the machine type 765 number as it appears in the ARM machine registry 766 (see http://www.arm.linux.org.uk/developer/machines/). 767 Only boards that have multiple machine types supported 768 in a single configuration file and the machine type is 769 runtime discoverable, do not have to use this setting. 770 771- vxWorks boot parameters: 772 773 bootvx constructs a valid bootline using the following 774 environments variables: bootfile, ipaddr, serverip, hostname. 775 It loads the vxWorks image pointed bootfile. 776 777 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 778 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 779 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 780 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 781 782 CONFIG_SYS_VXWORKS_ADD_PARAMS 783 784 Add it at the end of the bootline. E.g "u=username pw=secret" 785 786 Note: If a "bootargs" environment is defined, it will overwride 787 the defaults discussed just above. 788 789- Cache Configuration: 790 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 791 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 792 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 793 794- Cache Configuration for ARM: 795 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 796 controller 797 CONFIG_SYS_PL310_BASE - Physical base address of PL310 798 controller register space 799 800- Serial Ports: 801 CONFIG_PL010_SERIAL 802 803 Define this if you want support for Amba PrimeCell PL010 UARTs. 804 805 CONFIG_PL011_SERIAL 806 807 Define this if you want support for Amba PrimeCell PL011 UARTs. 808 809 CONFIG_PL011_CLOCK 810 811 If you have Amba PrimeCell PL011 UARTs, set this variable to 812 the clock speed of the UARTs. 813 814 CONFIG_PL01x_PORTS 815 816 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 817 define this to a list of base addresses for each (supported) 818 port. See e.g. include/configs/versatile.h 819 820 CONFIG_PL011_SERIAL_RLCR 821 822 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 823 have separate receive and transmit line control registers. Set 824 this variable to initialize the extra register. 825 826 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 827 828 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 829 boot loader that has already initialized the UART. Define this 830 variable to flush the UART at init time. 831 832 CONFIG_SERIAL_HW_FLOW_CONTROL 833 834 Define this variable to enable hw flow control in serial driver. 835 Current user of this option is drivers/serial/nsl16550.c driver 836 837- Console Interface: 838 Depending on board, define exactly one serial port 839 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 840 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 841 console by defining CONFIG_8xx_CONS_NONE 842 843 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 844 port routines must be defined elsewhere 845 (i.e. serial_init(), serial_getc(), ...) 846 847 CONFIG_CFB_CONSOLE 848 Enables console device for a color framebuffer. Needs following 849 defines (cf. smiLynxEM, i8042) 850 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 851 (default big endian) 852 VIDEO_HW_RECTFILL graphic chip supports 853 rectangle fill 854 (cf. smiLynxEM) 855 VIDEO_HW_BITBLT graphic chip supports 856 bit-blit (cf. smiLynxEM) 857 VIDEO_VISIBLE_COLS visible pixel columns 858 (cols=pitch) 859 VIDEO_VISIBLE_ROWS visible pixel rows 860 VIDEO_PIXEL_SIZE bytes per pixel 861 VIDEO_DATA_FORMAT graphic data format 862 (0-5, cf. cfb_console.c) 863 VIDEO_FB_ADRS framebuffer address 864 VIDEO_KBD_INIT_FCT keyboard int fct 865 (i.e. i8042_kbd_init()) 866 VIDEO_TSTC_FCT test char fct 867 (i.e. i8042_tstc) 868 VIDEO_GETC_FCT get char fct 869 (i.e. i8042_getc) 870 CONFIG_CONSOLE_CURSOR cursor drawing on/off 871 (requires blink timer 872 cf. i8042.c) 873 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 874 CONFIG_CONSOLE_TIME display time/date info in 875 upper right corner 876 (requires CONFIG_CMD_DATE) 877 CONFIG_VIDEO_LOGO display Linux logo in 878 upper left corner 879 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 880 linux_logo.h for logo. 881 Requires CONFIG_VIDEO_LOGO 882 CONFIG_CONSOLE_EXTRA_INFO 883 additional board info beside 884 the logo 885 886 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 887 a limited number of ANSI escape sequences (cursor control, 888 erase functions and limited graphics rendition control). 889 890 When CONFIG_CFB_CONSOLE is defined, video console is 891 default i/o. Serial console can be forced with 892 environment 'console=serial'. 893 894 When CONFIG_SILENT_CONSOLE is defined, all console 895 messages (by U-Boot and Linux!) can be silenced with 896 the "silent" environment variable. See 897 doc/README.silent for more information. 898 899 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 900 is 0x00. 901 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 902 is 0xa0. 903 904- Console Baudrate: 905 CONFIG_BAUDRATE - in bps 906 Select one of the baudrates listed in 907 CONFIG_SYS_BAUDRATE_TABLE, see below. 908 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 909 910- Console Rx buffer length 911 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 912 the maximum receive buffer length for the SMC. 913 This option is actual only for 82xx and 8xx possible. 914 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 915 must be defined, to setup the maximum idle timeout for 916 the SMC. 917 918- Pre-Console Buffer: 919 Prior to the console being initialised (i.e. serial UART 920 initialised etc) all console output is silently discarded. 921 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 922 buffer any console messages prior to the console being 923 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 924 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 925 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 926 bytes are output before the console is initialised, the 927 earlier bytes are discarded. 928 929 'Sane' compilers will generate smaller code if 930 CONFIG_PRE_CON_BUF_SZ is a power of 2 931 932- Safe printf() functions 933 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 934 the printf() functions. These are defined in 935 include/vsprintf.h and include snprintf(), vsnprintf() and 936 so on. Code size increase is approximately 300-500 bytes. 937 If this option is not given then these functions will 938 silently discard their buffer size argument - this means 939 you are not getting any overflow checking in this case. 940 941- Boot Delay: CONFIG_BOOTDELAY - in seconds 942 Delay before automatically booting the default image; 943 set to -1 to disable autoboot. 944 set to -2 to autoboot with no delay and not check for abort 945 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 946 947 See doc/README.autoboot for these options that 948 work with CONFIG_BOOTDELAY. None are required. 949 CONFIG_BOOT_RETRY_TIME 950 CONFIG_BOOT_RETRY_MIN 951 CONFIG_AUTOBOOT_KEYED 952 CONFIG_AUTOBOOT_PROMPT 953 CONFIG_AUTOBOOT_DELAY_STR 954 CONFIG_AUTOBOOT_STOP_STR 955 CONFIG_AUTOBOOT_DELAY_STR2 956 CONFIG_AUTOBOOT_STOP_STR2 957 CONFIG_ZERO_BOOTDELAY_CHECK 958 CONFIG_RESET_TO_RETRY 959 960- Autoboot Command: 961 CONFIG_BOOTCOMMAND 962 Only needed when CONFIG_BOOTDELAY is enabled; 963 define a command string that is automatically executed 964 when no character is read on the console interface 965 within "Boot Delay" after reset. 966 967 CONFIG_BOOTARGS 968 This can be used to pass arguments to the bootm 969 command. The value of CONFIG_BOOTARGS goes into the 970 environment value "bootargs". 971 972 CONFIG_RAMBOOT and CONFIG_NFSBOOT 973 The value of these goes into the environment as 974 "ramboot" and "nfsboot" respectively, and can be used 975 as a convenience, when switching between booting from 976 RAM and NFS. 977 978- Bootcount: 979 CONFIG_BOOTCOUNT_LIMIT 980 Implements a mechanism for detecting a repeating reboot 981 cycle, see: 982 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 983 984 CONFIG_BOOTCOUNT_ENV 985 If no softreset save registers are found on the hardware 986 "bootcount" is stored in the environment. To prevent a 987 saveenv on all reboots, the environment variable 988 "upgrade_available" is used. If "upgrade_available" is 989 0, "bootcount" is always 0, if "upgrade_available" is 990 1 "bootcount" is incremented in the environment. 991 So the Userspace Applikation must set the "upgrade_available" 992 and "bootcount" variable to 0, if a boot was successfully. 993 994- Pre-Boot Commands: 995 CONFIG_PREBOOT 996 997 When this option is #defined, the existence of the 998 environment variable "preboot" will be checked 999 immediately before starting the CONFIG_BOOTDELAY 1000 countdown and/or running the auto-boot command resp. 1001 entering interactive mode. 1002 1003 This feature is especially useful when "preboot" is 1004 automatically generated or modified. For an example 1005 see the LWMON board specific code: here "preboot" is 1006 modified when the user holds down a certain 1007 combination of keys on the (special) keyboard when 1008 booting the systems 1009 1010- Serial Download Echo Mode: 1011 CONFIG_LOADS_ECHO 1012 If defined to 1, all characters received during a 1013 serial download (using the "loads" command) are 1014 echoed back. This might be needed by some terminal 1015 emulations (like "cu"), but may as well just take 1016 time on others. This setting #define's the initial 1017 value of the "loads_echo" environment variable. 1018 1019- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 1020 CONFIG_KGDB_BAUDRATE 1021 Select one of the baudrates listed in 1022 CONFIG_SYS_BAUDRATE_TABLE, see below. 1023 1024- Monitor Functions: 1025 Monitor commands can be included or excluded 1026 from the build by using the #include files 1027 <config_cmd_all.h> and #undef'ing unwanted 1028 commands, or using <config_cmd_default.h> 1029 and augmenting with additional #define's 1030 for wanted commands. 1031 1032 The default command configuration includes all commands 1033 except those marked below with a "*". 1034 1035 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 1036 CONFIG_CMD_ASKENV * ask for env variable 1037 CONFIG_CMD_BDI bdinfo 1038 CONFIG_CMD_BEDBUG * Include BedBug Debugger 1039 CONFIG_CMD_BMP * BMP support 1040 CONFIG_CMD_BSP * Board specific commands 1041 CONFIG_CMD_BOOTD bootd 1042 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 1043 CONFIG_CMD_CACHE * icache, dcache 1044 CONFIG_CMD_CLK * clock command support 1045 CONFIG_CMD_CONSOLE coninfo 1046 CONFIG_CMD_CRC32 * crc32 1047 CONFIG_CMD_DATE * support for RTC, date/time... 1048 CONFIG_CMD_DHCP * DHCP support 1049 CONFIG_CMD_DIAG * Diagnostics 1050 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 1051 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 1052 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 1053 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 1054 CONFIG_CMD_DTT * Digital Therm and Thermostat 1055 CONFIG_CMD_ECHO echo arguments 1056 CONFIG_CMD_EDITENV edit env variable 1057 CONFIG_CMD_EEPROM * EEPROM read/write support 1058 CONFIG_CMD_ELF * bootelf, bootvx 1059 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 1060 CONFIG_CMD_ENV_FLAGS * display details about env flags 1061 CONFIG_CMD_ENV_EXISTS * check existence of env variable 1062 CONFIG_CMD_EXPORTENV * export the environment 1063 CONFIG_CMD_EXT2 * ext2 command support 1064 CONFIG_CMD_EXT4 * ext4 command support 1065 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 1066 that work for multiple fs types 1067 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 1068 CONFIG_CMD_SAVEENV saveenv 1069 CONFIG_CMD_FDC * Floppy Disk Support 1070 CONFIG_CMD_FAT * FAT command support 1071 CONFIG_CMD_FLASH flinfo, erase, protect 1072 CONFIG_CMD_FPGA FPGA device initialization support 1073 CONFIG_CMD_FUSE * Device fuse support 1074 CONFIG_CMD_GETTIME * Get time since boot 1075 CONFIG_CMD_GO * the 'go' command (exec code) 1076 CONFIG_CMD_GREPENV * search environment 1077 CONFIG_CMD_HASH * calculate hash / digest 1078 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 1079 CONFIG_CMD_I2C * I2C serial bus support 1080 CONFIG_CMD_IDE * IDE harddisk support 1081 CONFIG_CMD_IMI iminfo 1082 CONFIG_CMD_IMLS List all images found in NOR flash 1083 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1084 CONFIG_CMD_IMMAP * IMMR dump support 1085 CONFIG_CMD_IOTRACE * I/O tracing for debugging 1086 CONFIG_CMD_IMPORTENV * import an environment 1087 CONFIG_CMD_INI * import data from an ini file into the env 1088 CONFIG_CMD_IRQ * irqinfo 1089 CONFIG_CMD_ITEST Integer/string test of 2 values 1090 CONFIG_CMD_JFFS2 * JFFS2 Support 1091 CONFIG_CMD_KGDB * kgdb 1092 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1093 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1094 (169.254.*.*) 1095 CONFIG_CMD_LOADB loadb 1096 CONFIG_CMD_LOADS loads 1097 CONFIG_CMD_MD5SUM * print md5 message digest 1098 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1099 CONFIG_CMD_MEMINFO * Display detailed memory information 1100 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1101 loop, loopw 1102 CONFIG_CMD_MEMTEST * mtest 1103 CONFIG_CMD_MISC Misc functions like sleep etc 1104 CONFIG_CMD_MMC * MMC memory mapped support 1105 CONFIG_CMD_MII * MII utility commands 1106 CONFIG_CMD_MTDPARTS * MTD partition support 1107 CONFIG_CMD_NAND * NAND support 1108 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1109 CONFIG_CMD_NFS NFS support 1110 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1111 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1112 CONFIG_CMD_PCI * pciinfo 1113 CONFIG_CMD_PCMCIA * PCMCIA support 1114 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1115 host 1116 CONFIG_CMD_PORTIO * Port I/O 1117 CONFIG_CMD_READ * Read raw data from partition 1118 CONFIG_CMD_REGINFO * Register dump 1119 CONFIG_CMD_RUN run command in env variable 1120 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1121 CONFIG_CMD_SAVES * save S record dump 1122 CONFIG_CMD_SCSI * SCSI Support 1123 CONFIG_CMD_SDRAM * print SDRAM configuration information 1124 (requires CONFIG_CMD_I2C) 1125 CONFIG_CMD_SETGETDCR Support for DCR Register access 1126 (4xx only) 1127 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1128 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1129 (requires CONFIG_CMD_MEMORY) 1130 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1131 CONFIG_CMD_SOURCE "source" command Support 1132 CONFIG_CMD_SPI * SPI serial bus support 1133 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1134 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1135 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1136 CONFIG_CMD_TIMER * access to the system tick timer 1137 CONFIG_CMD_USB * USB support 1138 CONFIG_CMD_CDP * Cisco Discover Protocol support 1139 CONFIG_CMD_MFSL * Microblaze FSL support 1140 CONFIG_CMD_XIMG Load part of Multi Image 1141 CONFIG_CMD_UUID * Generate random UUID or GUID string 1142 1143 EXAMPLE: If you want all functions except of network 1144 support you can write: 1145 1146 #include "config_cmd_all.h" 1147 #undef CONFIG_CMD_NET 1148 1149 Other Commands: 1150 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1151 1152 Note: Don't enable the "icache" and "dcache" commands 1153 (configuration option CONFIG_CMD_CACHE) unless you know 1154 what you (and your U-Boot users) are doing. Data 1155 cache cannot be enabled on systems like the 8xx or 1156 8260 (where accesses to the IMMR region must be 1157 uncached), and it cannot be disabled on all other 1158 systems where we (mis-) use the data cache to hold an 1159 initial stack and some data. 1160 1161 1162 XXX - this list needs to get updated! 1163 1164- Regular expression support: 1165 CONFIG_REGEX 1166 If this variable is defined, U-Boot is linked against 1167 the SLRE (Super Light Regular Expression) library, 1168 which adds regex support to some commands, as for 1169 example "env grep" and "setexpr". 1170 1171- Device tree: 1172 CONFIG_OF_CONTROL 1173 If this variable is defined, U-Boot will use a device tree 1174 to configure its devices, instead of relying on statically 1175 compiled #defines in the board file. This option is 1176 experimental and only available on a few boards. The device 1177 tree is available in the global data as gd->fdt_blob. 1178 1179 U-Boot needs to get its device tree from somewhere. This can 1180 be done using one of the two options below: 1181 1182 CONFIG_OF_EMBED 1183 If this variable is defined, U-Boot will embed a device tree 1184 binary in its image. This device tree file should be in the 1185 board directory and called <soc>-<board>.dts. The binary file 1186 is then picked up in board_init_f() and made available through 1187 the global data structure as gd->blob. 1188 1189 CONFIG_OF_SEPARATE 1190 If this variable is defined, U-Boot will build a device tree 1191 binary. It will be called u-boot.dtb. Architecture-specific 1192 code will locate it at run-time. Generally this works by: 1193 1194 cat u-boot.bin u-boot.dtb >image.bin 1195 1196 and in fact, U-Boot does this for you, creating a file called 1197 u-boot-dtb.bin which is useful in the common case. You can 1198 still use the individual files if you need something more 1199 exotic. 1200 1201- Watchdog: 1202 CONFIG_WATCHDOG 1203 If this variable is defined, it enables watchdog 1204 support for the SoC. There must be support in the SoC 1205 specific code for a watchdog. For the 8xx and 8260 1206 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1207 register. When supported for a specific SoC is 1208 available, then no further board specific code should 1209 be needed to use it. 1210 1211 CONFIG_HW_WATCHDOG 1212 When using a watchdog circuitry external to the used 1213 SoC, then define this variable and provide board 1214 specific code for the "hw_watchdog_reset" function. 1215 1216 CONFIG_AT91_HW_WDT_TIMEOUT 1217 specify the timeout in seconds. default 2 seconds. 1218 1219- U-Boot Version: 1220 CONFIG_VERSION_VARIABLE 1221 If this variable is defined, an environment variable 1222 named "ver" is created by U-Boot showing the U-Boot 1223 version as printed by the "version" command. 1224 Any change to this variable will be reverted at the 1225 next reset. 1226 1227- Real-Time Clock: 1228 1229 When CONFIG_CMD_DATE is selected, the type of the RTC 1230 has to be selected, too. Define exactly one of the 1231 following options: 1232 1233 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1234 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1235 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1236 CONFIG_RTC_MC146818 - use MC146818 RTC 1237 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1238 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1239 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1240 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1241 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1242 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1243 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1244 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1245 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1246 RV3029 RTC. 1247 1248 Note that if the RTC uses I2C, then the I2C interface 1249 must also be configured. See I2C Support, below. 1250 1251- GPIO Support: 1252 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1253 1254 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1255 chip-ngpio pairs that tell the PCA953X driver the number of 1256 pins supported by a particular chip. 1257 1258 Note that if the GPIO device uses I2C, then the I2C interface 1259 must also be configured. See I2C Support, below. 1260 1261- I/O tracing: 1262 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1263 accesses and can checksum them or write a list of them out 1264 to memory. See the 'iotrace' command for details. This is 1265 useful for testing device drivers since it can confirm that 1266 the driver behaves the same way before and after a code 1267 change. Currently this is supported on sandbox and arm. To 1268 add support for your architecture, add '#include <iotrace.h>' 1269 to the bottom of arch/<arch>/include/asm/io.h and test. 1270 1271 Example output from the 'iotrace stats' command is below. 1272 Note that if the trace buffer is exhausted, the checksum will 1273 still continue to operate. 1274 1275 iotrace is enabled 1276 Start: 10000000 (buffer start address) 1277 Size: 00010000 (buffer size) 1278 Offset: 00000120 (current buffer offset) 1279 Output: 10000120 (start + offset) 1280 Count: 00000018 (number of trace records) 1281 CRC32: 9526fb66 (CRC32 of all trace records) 1282 1283- Timestamp Support: 1284 1285 When CONFIG_TIMESTAMP is selected, the timestamp 1286 (date and time) of an image is printed by image 1287 commands like bootm or iminfo. This option is 1288 automatically enabled when you select CONFIG_CMD_DATE . 1289 1290- Partition Labels (disklabels) Supported: 1291 Zero or more of the following: 1292 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1293 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1294 Intel architecture, USB sticks, etc. 1295 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1296 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1297 bootloader. Note 2TB partition limit; see 1298 disk/part_efi.c 1299 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1300 1301 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1302 CONFIG_CMD_SCSI) you must configure support for at 1303 least one non-MTD partition type as well. 1304 1305- IDE Reset method: 1306 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1307 board configurations files but used nowhere! 1308 1309 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1310 be performed by calling the function 1311 ide_set_reset(int reset) 1312 which has to be defined in a board specific file 1313 1314- ATAPI Support: 1315 CONFIG_ATAPI 1316 1317 Set this to enable ATAPI support. 1318 1319- LBA48 Support 1320 CONFIG_LBA48 1321 1322 Set this to enable support for disks larger than 137GB 1323 Also look at CONFIG_SYS_64BIT_LBA. 1324 Whithout these , LBA48 support uses 32bit variables and will 'only' 1325 support disks up to 2.1TB. 1326 1327 CONFIG_SYS_64BIT_LBA: 1328 When enabled, makes the IDE subsystem use 64bit sector addresses. 1329 Default is 32bit. 1330 1331- SCSI Support: 1332 At the moment only there is only support for the 1333 SYM53C8XX SCSI controller; define 1334 CONFIG_SCSI_SYM53C8XX to enable it. 1335 1336 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1337 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1338 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1339 maximum numbers of LUNs, SCSI ID's and target 1340 devices. 1341 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1342 1343 The environment variable 'scsidevs' is set to the number of 1344 SCSI devices found during the last scan. 1345 1346- NETWORK Support (PCI): 1347 CONFIG_E1000 1348 Support for Intel 8254x/8257x gigabit chips. 1349 1350 CONFIG_E1000_SPI 1351 Utility code for direct access to the SPI bus on Intel 8257x. 1352 This does not do anything useful unless you set at least one 1353 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1354 1355 CONFIG_E1000_SPI_GENERIC 1356 Allow generic access to the SPI bus on the Intel 8257x, for 1357 example with the "sspi" command. 1358 1359 CONFIG_CMD_E1000 1360 Management command for E1000 devices. When used on devices 1361 with SPI support you can reprogram the EEPROM from U-Boot. 1362 1363 CONFIG_E1000_FALLBACK_MAC 1364 default MAC for empty EEPROM after production. 1365 1366 CONFIG_EEPRO100 1367 Support for Intel 82557/82559/82559ER chips. 1368 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1369 write routine for first time initialisation. 1370 1371 CONFIG_TULIP 1372 Support for Digital 2114x chips. 1373 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1374 modem chip initialisation (KS8761/QS6611). 1375 1376 CONFIG_NATSEMI 1377 Support for National dp83815 chips. 1378 1379 CONFIG_NS8382X 1380 Support for National dp8382[01] gigabit chips. 1381 1382- NETWORK Support (other): 1383 1384 CONFIG_DRIVER_AT91EMAC 1385 Support for AT91RM9200 EMAC. 1386 1387 CONFIG_RMII 1388 Define this to use reduced MII inteface 1389 1390 CONFIG_DRIVER_AT91EMAC_QUIET 1391 If this defined, the driver is quiet. 1392 The driver doen't show link status messages. 1393 1394 CONFIG_CALXEDA_XGMAC 1395 Support for the Calxeda XGMAC device 1396 1397 CONFIG_LAN91C96 1398 Support for SMSC's LAN91C96 chips. 1399 1400 CONFIG_LAN91C96_BASE 1401 Define this to hold the physical address 1402 of the LAN91C96's I/O space 1403 1404 CONFIG_LAN91C96_USE_32_BIT 1405 Define this to enable 32 bit addressing 1406 1407 CONFIG_SMC91111 1408 Support for SMSC's LAN91C111 chip 1409 1410 CONFIG_SMC91111_BASE 1411 Define this to hold the physical address 1412 of the device (I/O space) 1413 1414 CONFIG_SMC_USE_32_BIT 1415 Define this if data bus is 32 bits 1416 1417 CONFIG_SMC_USE_IOFUNCS 1418 Define this to use i/o functions instead of macros 1419 (some hardware wont work with macros) 1420 1421 CONFIG_DRIVER_TI_EMAC 1422 Support for davinci emac 1423 1424 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1425 Define this if you have more then 3 PHYs. 1426 1427 CONFIG_FTGMAC100 1428 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1429 1430 CONFIG_FTGMAC100_EGIGA 1431 Define this to use GE link update with gigabit PHY. 1432 Define this if FTGMAC100 is connected to gigabit PHY. 1433 If your system has 10/100 PHY only, it might not occur 1434 wrong behavior. Because PHY usually return timeout or 1435 useless data when polling gigabit status and gigabit 1436 control registers. This behavior won't affect the 1437 correctnessof 10/100 link speed update. 1438 1439 CONFIG_SMC911X 1440 Support for SMSC's LAN911x and LAN921x chips 1441 1442 CONFIG_SMC911X_BASE 1443 Define this to hold the physical address 1444 of the device (I/O space) 1445 1446 CONFIG_SMC911X_32_BIT 1447 Define this if data bus is 32 bits 1448 1449 CONFIG_SMC911X_16_BIT 1450 Define this if data bus is 16 bits. If your processor 1451 automatically converts one 32 bit word to two 16 bit 1452 words you may also try CONFIG_SMC911X_32_BIT. 1453 1454 CONFIG_SH_ETHER 1455 Support for Renesas on-chip Ethernet controller 1456 1457 CONFIG_SH_ETHER_USE_PORT 1458 Define the number of ports to be used 1459 1460 CONFIG_SH_ETHER_PHY_ADDR 1461 Define the ETH PHY's address 1462 1463 CONFIG_SH_ETHER_CACHE_WRITEBACK 1464 If this option is set, the driver enables cache flush. 1465 1466- PWM Support: 1467 CONFIG_PWM_IMX 1468 Support for PWM modul on the imx6. 1469 1470- TPM Support: 1471 CONFIG_TPM 1472 Support TPM devices. 1473 1474 CONFIG_TPM_TIS_I2C 1475 Support for i2c bus TPM devices. Only one device 1476 per system is supported at this time. 1477 1478 CONFIG_TPM_TIS_I2C_BUS_NUMBER 1479 Define the the i2c bus number for the TPM device 1480 1481 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS 1482 Define the TPM's address on the i2c bus 1483 1484 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1485 Define the burst count bytes upper limit 1486 1487 CONFIG_TPM_ATMEL_TWI 1488 Support for Atmel TWI TPM device. Requires I2C support. 1489 1490 CONFIG_TPM_TIS_LPC 1491 Support for generic parallel port TPM devices. Only one device 1492 per system is supported at this time. 1493 1494 CONFIG_TPM_TIS_BASE_ADDRESS 1495 Base address where the generic TPM device is mapped 1496 to. Contemporary x86 systems usually map it at 1497 0xfed40000. 1498 1499 CONFIG_CMD_TPM 1500 Add tpm monitor functions. 1501 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1502 provides monitor access to authorized functions. 1503 1504 CONFIG_TPM 1505 Define this to enable the TPM support library which provides 1506 functional interfaces to some TPM commands. 1507 Requires support for a TPM device. 1508 1509 CONFIG_TPM_AUTH_SESSIONS 1510 Define this to enable authorized functions in the TPM library. 1511 Requires CONFIG_TPM and CONFIG_SHA1. 1512 1513- USB Support: 1514 At the moment only the UHCI host controller is 1515 supported (PIP405, MIP405, MPC5200); define 1516 CONFIG_USB_UHCI to enable it. 1517 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1518 and define CONFIG_USB_STORAGE to enable the USB 1519 storage devices. 1520 Note: 1521 Supported are USB Keyboards and USB Floppy drives 1522 (TEAC FD-05PUB). 1523 MPC5200 USB requires additional defines: 1524 CONFIG_USB_CLOCK 1525 for 528 MHz Clock: 0x0001bbbb 1526 CONFIG_PSC3_USB 1527 for USB on PSC3 1528 CONFIG_USB_CONFIG 1529 for differential drivers: 0x00001000 1530 for single ended drivers: 0x00005000 1531 for differential drivers on PSC3: 0x00000100 1532 for single ended drivers on PSC3: 0x00004100 1533 CONFIG_SYS_USB_EVENT_POLL 1534 May be defined to allow interrupt polling 1535 instead of using asynchronous interrupts 1536 1537 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1538 txfilltuning field in the EHCI controller on reset. 1539 1540 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1541 HW module registers. 1542 1543- USB Device: 1544 Define the below if you wish to use the USB console. 1545 Once firmware is rebuilt from a serial console issue the 1546 command "setenv stdin usbtty; setenv stdout usbtty" and 1547 attach your USB cable. The Unix command "dmesg" should print 1548 it has found a new device. The environment variable usbtty 1549 can be set to gserial or cdc_acm to enable your device to 1550 appear to a USB host as a Linux gserial device or a 1551 Common Device Class Abstract Control Model serial device. 1552 If you select usbtty = gserial you should be able to enumerate 1553 a Linux host by 1554 # modprobe usbserial vendor=0xVendorID product=0xProductID 1555 else if using cdc_acm, simply setting the environment 1556 variable usbtty to be cdc_acm should suffice. The following 1557 might be defined in YourBoardName.h 1558 1559 CONFIG_USB_DEVICE 1560 Define this to build a UDC device 1561 1562 CONFIG_USB_TTY 1563 Define this to have a tty type of device available to 1564 talk to the UDC device 1565 1566 CONFIG_USBD_HS 1567 Define this to enable the high speed support for usb 1568 device and usbtty. If this feature is enabled, a routine 1569 int is_usbd_high_speed(void) 1570 also needs to be defined by the driver to dynamically poll 1571 whether the enumeration has succeded at high speed or full 1572 speed. 1573 1574 CONFIG_SYS_CONSOLE_IS_IN_ENV 1575 Define this if you want stdin, stdout &/or stderr to 1576 be set to usbtty. 1577 1578 mpc8xx: 1579 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1580 Derive USB clock from external clock "blah" 1581 - CONFIG_SYS_USB_EXTC_CLK 0x02 1582 1583 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1584 Derive USB clock from brgclk 1585 - CONFIG_SYS_USB_BRG_CLK 0x04 1586 1587 If you have a USB-IF assigned VendorID then you may wish to 1588 define your own vendor specific values either in BoardName.h 1589 or directly in usbd_vendor_info.h. If you don't define 1590 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1591 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1592 should pretend to be a Linux device to it's target host. 1593 1594 CONFIG_USBD_MANUFACTURER 1595 Define this string as the name of your company for 1596 - CONFIG_USBD_MANUFACTURER "my company" 1597 1598 CONFIG_USBD_PRODUCT_NAME 1599 Define this string as the name of your product 1600 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1601 1602 CONFIG_USBD_VENDORID 1603 Define this as your assigned Vendor ID from the USB 1604 Implementors Forum. This *must* be a genuine Vendor ID 1605 to avoid polluting the USB namespace. 1606 - CONFIG_USBD_VENDORID 0xFFFF 1607 1608 CONFIG_USBD_PRODUCTID 1609 Define this as the unique Product ID 1610 for your device 1611 - CONFIG_USBD_PRODUCTID 0xFFFF 1612 1613- ULPI Layer Support: 1614 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1615 the generic ULPI layer. The generic layer accesses the ULPI PHY 1616 via the platform viewport, so you need both the genric layer and 1617 the viewport enabled. Currently only Chipidea/ARC based 1618 viewport is supported. 1619 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1620 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1621 If your ULPI phy needs a different reference clock than the 1622 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1623 the appropriate value in Hz. 1624 1625- MMC Support: 1626 The MMC controller on the Intel PXA is supported. To 1627 enable this define CONFIG_MMC. The MMC can be 1628 accessed from the boot prompt by mapping the device 1629 to physical memory similar to flash. Command line is 1630 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1631 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1632 1633 CONFIG_SH_MMCIF 1634 Support for Renesas on-chip MMCIF controller 1635 1636 CONFIG_SH_MMCIF_ADDR 1637 Define the base address of MMCIF registers 1638 1639 CONFIG_SH_MMCIF_CLK 1640 Define the clock frequency for MMCIF 1641 1642 CONFIG_GENERIC_MMC 1643 Enable the generic MMC driver 1644 1645 CONFIG_SUPPORT_EMMC_BOOT 1646 Enable some additional features of the eMMC boot partitions. 1647 1648 CONFIG_SUPPORT_EMMC_RPMB 1649 Enable the commands for reading, writing and programming the 1650 key for the Replay Protection Memory Block partition in eMMC. 1651 1652- USB Device Firmware Update (DFU) class support: 1653 CONFIG_DFU_FUNCTION 1654 This enables the USB portion of the DFU USB class 1655 1656 CONFIG_CMD_DFU 1657 This enables the command "dfu" which is used to have 1658 U-Boot create a DFU class device via USB. This command 1659 requires that the "dfu_alt_info" environment variable be 1660 set and define the alt settings to expose to the host. 1661 1662 CONFIG_DFU_MMC 1663 This enables support for exposing (e)MMC devices via DFU. 1664 1665 CONFIG_DFU_NAND 1666 This enables support for exposing NAND devices via DFU. 1667 1668 CONFIG_DFU_RAM 1669 This enables support for exposing RAM via DFU. 1670 Note: DFU spec refer to non-volatile memory usage, but 1671 allow usages beyond the scope of spec - here RAM usage, 1672 one that would help mostly the developer. 1673 1674 CONFIG_SYS_DFU_DATA_BUF_SIZE 1675 Dfu transfer uses a buffer before writing data to the 1676 raw storage device. Make the size (in bytes) of this buffer 1677 configurable. The size of this buffer is also configurable 1678 through the "dfu_bufsiz" environment variable. 1679 1680 CONFIG_SYS_DFU_MAX_FILE_SIZE 1681 When updating files rather than the raw storage device, 1682 we use a static buffer to copy the file into and then write 1683 the buffer once we've been given the whole file. Define 1684 this to the maximum filesize (in bytes) for the buffer. 1685 Default is 4 MiB if undefined. 1686 1687 DFU_DEFAULT_POLL_TIMEOUT 1688 Poll timeout [ms], is the timeout a device can send to the 1689 host. The host must wait for this timeout before sending 1690 a subsequent DFU_GET_STATUS request to the device. 1691 1692 DFU_MANIFEST_POLL_TIMEOUT 1693 Poll timeout [ms], which the device sends to the host when 1694 entering dfuMANIFEST state. Host waits this timeout, before 1695 sending again an USB request to the device. 1696 1697- USB Device Android Fastboot support: 1698 CONFIG_CMD_FASTBOOT 1699 This enables the command "fastboot" which enables the Android 1700 fastboot mode for the platform's USB device. Fastboot is a USB 1701 protocol for downloading images, flashing and device control 1702 used on Android devices. 1703 See doc/README.android-fastboot for more information. 1704 1705 CONFIG_ANDROID_BOOT_IMAGE 1706 This enables support for booting images which use the Android 1707 image format header. 1708 1709 CONFIG_USB_FASTBOOT_BUF_ADDR 1710 The fastboot protocol requires a large memory buffer for 1711 downloads. Define this to the starting RAM address to use for 1712 downloaded images. 1713 1714 CONFIG_USB_FASTBOOT_BUF_SIZE 1715 The fastboot protocol requires a large memory buffer for 1716 downloads. This buffer should be as large as possible for a 1717 platform. Define this to the size available RAM for fastboot. 1718 1719 CONFIG_FASTBOOT_FLASH 1720 The fastboot protocol includes a "flash" command for writing 1721 the downloaded image to a non-volatile storage device. Define 1722 this to enable the "fastboot flash" command. 1723 1724 CONFIG_FASTBOOT_FLASH_MMC_DEV 1725 The fastboot "flash" command requires additional information 1726 regarding the non-volatile storage device. Define this to 1727 the eMMC device that fastboot should use to store the image. 1728 1729 CONFIG_FASTBOOT_GPT_NAME 1730 The fastboot "flash" command supports writing the downloaded 1731 image to the Protective MBR and the Primary GUID Partition 1732 Table. (Additionally, this downloaded image is post-processed 1733 to generate and write the Backup GUID Partition Table.) 1734 This occurs when the specified "partition name" on the 1735 "fastboot flash" command line matches this value. 1736 Default is GPT_ENTRY_NAME (currently "gpt") if undefined. 1737 1738- Journaling Flash filesystem support: 1739 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1740 CONFIG_JFFS2_NAND_DEV 1741 Define these for a default partition on a NAND device 1742 1743 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1744 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1745 Define these for a default partition on a NOR device 1746 1747 CONFIG_SYS_JFFS_CUSTOM_PART 1748 Define this to create an own partition. You have to provide a 1749 function struct part_info* jffs2_part_info(int part_num) 1750 1751 If you define only one JFFS2 partition you may also want to 1752 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1753 to disable the command chpart. This is the default when you 1754 have not defined a custom partition 1755 1756- FAT(File Allocation Table) filesystem write function support: 1757 CONFIG_FAT_WRITE 1758 1759 Define this to enable support for saving memory data as a 1760 file in FAT formatted partition. 1761 1762 This will also enable the command "fatwrite" enabling the 1763 user to write files to FAT. 1764 1765CBFS (Coreboot Filesystem) support 1766 CONFIG_CMD_CBFS 1767 1768 Define this to enable support for reading from a Coreboot 1769 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1770 and cbfsload. 1771 1772- FAT(File Allocation Table) filesystem cluster size: 1773 CONFIG_FS_FAT_MAX_CLUSTSIZE 1774 1775 Define the max cluster size for fat operations else 1776 a default value of 65536 will be defined. 1777 1778- Keyboard Support: 1779 CONFIG_ISA_KEYBOARD 1780 1781 Define this to enable standard (PC-Style) keyboard 1782 support 1783 1784 CONFIG_I8042_KBD 1785 Standard PC keyboard driver with US (is default) and 1786 GERMAN key layout (switch via environment 'keymap=de') support. 1787 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1788 for cfb_console. Supports cursor blinking. 1789 1790 CONFIG_CROS_EC_KEYB 1791 Enables a Chrome OS keyboard using the CROS_EC interface. 1792 This uses CROS_EC to communicate with a second microcontroller 1793 which provides key scans on request. 1794 1795- Video support: 1796 CONFIG_VIDEO 1797 1798 Define this to enable video support (for output to 1799 video). 1800 1801 CONFIG_VIDEO_CT69000 1802 1803 Enable Chips & Technologies 69000 Video chip 1804 1805 CONFIG_VIDEO_SMI_LYNXEM 1806 Enable Silicon Motion SMI 712/710/810 Video chip. The 1807 video output is selected via environment 'videoout' 1808 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1809 assumed. 1810 1811 For the CT69000 and SMI_LYNXEM drivers, videomode is 1812 selected via environment 'videomode'. Two different ways 1813 are possible: 1814 - "videomode=num" 'num' is a standard LiLo mode numbers. 1815 Following standard modes are supported (* is default): 1816 1817 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1818 -------------+--------------------------------------------- 1819 8 bits | 0x301* 0x303 0x305 0x161 0x307 1820 15 bits | 0x310 0x313 0x316 0x162 0x319 1821 16 bits | 0x311 0x314 0x317 0x163 0x31A 1822 24 bits | 0x312 0x315 0x318 ? 0x31B 1823 -------------+--------------------------------------------- 1824 (i.e. setenv videomode 317; saveenv; reset;) 1825 1826 - "videomode=bootargs" all the video parameters are parsed 1827 from the bootargs. (See drivers/video/videomodes.c) 1828 1829 1830 CONFIG_VIDEO_SED13806 1831 Enable Epson SED13806 driver. This driver supports 8bpp 1832 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1833 or CONFIG_VIDEO_SED13806_16BPP 1834 1835 CONFIG_FSL_DIU_FB 1836 Enable the Freescale DIU video driver. Reference boards for 1837 SOCs that have a DIU should define this macro to enable DIU 1838 support, and should also define these other macros: 1839 1840 CONFIG_SYS_DIU_ADDR 1841 CONFIG_VIDEO 1842 CONFIG_CMD_BMP 1843 CONFIG_CFB_CONSOLE 1844 CONFIG_VIDEO_SW_CURSOR 1845 CONFIG_VGA_AS_SINGLE_DEVICE 1846 CONFIG_VIDEO_LOGO 1847 CONFIG_VIDEO_BMP_LOGO 1848 1849 The DIU driver will look for the 'video-mode' environment 1850 variable, and if defined, enable the DIU as a console during 1851 boot. See the documentation file README.video for a 1852 description of this variable. 1853 1854 CONFIG_VIDEO_VGA 1855 1856 Enable the VGA video / BIOS for x86. The alternative if you 1857 are using coreboot is to use the coreboot frame buffer 1858 driver. 1859 1860 1861- Keyboard Support: 1862 CONFIG_KEYBOARD 1863 1864 Define this to enable a custom keyboard support. 1865 This simply calls drv_keyboard_init() which must be 1866 defined in your board-specific files. 1867 The only board using this so far is RBC823. 1868 1869- LCD Support: CONFIG_LCD 1870 1871 Define this to enable LCD support (for output to LCD 1872 display); also select one of the supported displays 1873 by defining one of these: 1874 1875 CONFIG_ATMEL_LCD: 1876 1877 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1878 1879 CONFIG_NEC_NL6448AC33: 1880 1881 NEC NL6448AC33-18. Active, color, single scan. 1882 1883 CONFIG_NEC_NL6448BC20 1884 1885 NEC NL6448BC20-08. 6.5", 640x480. 1886 Active, color, single scan. 1887 1888 CONFIG_NEC_NL6448BC33_54 1889 1890 NEC NL6448BC33-54. 10.4", 640x480. 1891 Active, color, single scan. 1892 1893 CONFIG_SHARP_16x9 1894 1895 Sharp 320x240. Active, color, single scan. 1896 It isn't 16x9, and I am not sure what it is. 1897 1898 CONFIG_SHARP_LQ64D341 1899 1900 Sharp LQ64D341 display, 640x480. 1901 Active, color, single scan. 1902 1903 CONFIG_HLD1045 1904 1905 HLD1045 display, 640x480. 1906 Active, color, single scan. 1907 1908 CONFIG_OPTREX_BW 1909 1910 Optrex CBL50840-2 NF-FW 99 22 M5 1911 or 1912 Hitachi LMG6912RPFC-00T 1913 or 1914 Hitachi SP14Q002 1915 1916 320x240. Black & white. 1917 1918 Normally display is black on white background; define 1919 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1920 1921 CONFIG_LCD_ALIGNMENT 1922 1923 Normally the LCD is page-aligned (typically 4KB). If this is 1924 defined then the LCD will be aligned to this value instead. 1925 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1926 here, since it is cheaper to change data cache settings on 1927 a per-section basis. 1928 1929 CONFIG_CONSOLE_SCROLL_LINES 1930 1931 When the console need to be scrolled, this is the number of 1932 lines to scroll by. It defaults to 1. Increasing this makes 1933 the console jump but can help speed up operation when scrolling 1934 is slow. 1935 1936 CONFIG_LCD_BMP_RLE8 1937 1938 Support drawing of RLE8-compressed bitmaps on the LCD. 1939 1940 CONFIG_I2C_EDID 1941 1942 Enables an 'i2c edid' command which can read EDID 1943 information over I2C from an attached LCD display. 1944 1945- Splash Screen Support: CONFIG_SPLASH_SCREEN 1946 1947 If this option is set, the environment is checked for 1948 a variable "splashimage". If found, the usual display 1949 of logo, copyright and system information on the LCD 1950 is suppressed and the BMP image at the address 1951 specified in "splashimage" is loaded instead. The 1952 console is redirected to the "nulldev", too. This 1953 allows for a "silent" boot where a splash screen is 1954 loaded very quickly after power-on. 1955 1956 CONFIG_SPLASHIMAGE_GUARD 1957 1958 If this option is set, then U-Boot will prevent the environment 1959 variable "splashimage" from being set to a problematic address 1960 (see README.displaying-bmps). 1961 This option is useful for targets where, due to alignment 1962 restrictions, an improperly aligned BMP image will cause a data 1963 abort. If you think you will not have problems with unaligned 1964 accesses (for example because your toolchain prevents them) 1965 there is no need to set this option. 1966 1967 CONFIG_SPLASH_SCREEN_ALIGN 1968 1969 If this option is set the splash image can be freely positioned 1970 on the screen. Environment variable "splashpos" specifies the 1971 position as "x,y". If a positive number is given it is used as 1972 number of pixel from left/top. If a negative number is given it 1973 is used as number of pixel from right/bottom. You can also 1974 specify 'm' for centering the image. 1975 1976 Example: 1977 setenv splashpos m,m 1978 => image at center of screen 1979 1980 setenv splashpos 30,20 1981 => image at x = 30 and y = 20 1982 1983 setenv splashpos -10,m 1984 => vertically centered image 1985 at x = dspWidth - bmpWidth - 9 1986 1987- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1988 1989 If this option is set, additionally to standard BMP 1990 images, gzipped BMP images can be displayed via the 1991 splashscreen support or the bmp command. 1992 1993- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1994 1995 If this option is set, 8-bit RLE compressed BMP images 1996 can be displayed via the splashscreen support or the 1997 bmp command. 1998 1999- Do compressing for memory range: 2000 CONFIG_CMD_ZIP 2001 2002 If this option is set, it would use zlib deflate method 2003 to compress the specified memory at its best effort. 2004 2005- Compression support: 2006 CONFIG_GZIP 2007 2008 Enabled by default to support gzip compressed images. 2009 2010 CONFIG_BZIP2 2011 2012 If this option is set, support for bzip2 compressed 2013 images is included. If not, only uncompressed and gzip 2014 compressed images are supported. 2015 2016 NOTE: the bzip2 algorithm requires a lot of RAM, so 2017 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 2018 be at least 4MB. 2019 2020 CONFIG_LZMA 2021 2022 If this option is set, support for lzma compressed 2023 images is included. 2024 2025 Note: The LZMA algorithm adds between 2 and 4KB of code and it 2026 requires an amount of dynamic memory that is given by the 2027 formula: 2028 2029 (1846 + 768 << (lc + lp)) * sizeof(uint16) 2030 2031 Where lc and lp stand for, respectively, Literal context bits 2032 and Literal pos bits. 2033 2034 This value is upper-bounded by 14MB in the worst case. Anyway, 2035 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 2036 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 2037 a very small buffer. 2038 2039 Use the lzmainfo tool to determinate the lc and lp values and 2040 then calculate the amount of needed dynamic memory (ensuring 2041 the appropriate CONFIG_SYS_MALLOC_LEN value). 2042 2043 CONFIG_LZO 2044 2045 If this option is set, support for LZO compressed images 2046 is included. 2047 2048- MII/PHY support: 2049 CONFIG_PHY_ADDR 2050 2051 The address of PHY on MII bus. 2052 2053 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 2054 2055 The clock frequency of the MII bus 2056 2057 CONFIG_PHY_GIGE 2058 2059 If this option is set, support for speed/duplex 2060 detection of gigabit PHY is included. 2061 2062 CONFIG_PHY_RESET_DELAY 2063 2064 Some PHY like Intel LXT971A need extra delay after 2065 reset before any MII register access is possible. 2066 For such PHY, set this option to the usec delay 2067 required. (minimum 300usec for LXT971A) 2068 2069 CONFIG_PHY_CMD_DELAY (ppc4xx) 2070 2071 Some PHY like Intel LXT971A need extra delay after 2072 command issued before MII status register can be read 2073 2074- Ethernet address: 2075 CONFIG_ETHADDR 2076 CONFIG_ETH1ADDR 2077 CONFIG_ETH2ADDR 2078 CONFIG_ETH3ADDR 2079 CONFIG_ETH4ADDR 2080 CONFIG_ETH5ADDR 2081 2082 Define a default value for Ethernet address to use 2083 for the respective Ethernet interface, in case this 2084 is not determined automatically. 2085 2086- IP address: 2087 CONFIG_IPADDR 2088 2089 Define a default value for the IP address to use for 2090 the default Ethernet interface, in case this is not 2091 determined through e.g. bootp. 2092 (Environment variable "ipaddr") 2093 2094- Server IP address: 2095 CONFIG_SERVERIP 2096 2097 Defines a default value for the IP address of a TFTP 2098 server to contact when using the "tftboot" command. 2099 (Environment variable "serverip") 2100 2101 CONFIG_KEEP_SERVERADDR 2102 2103 Keeps the server's MAC address, in the env 'serveraddr' 2104 for passing to bootargs (like Linux's netconsole option) 2105 2106- Gateway IP address: 2107 CONFIG_GATEWAYIP 2108 2109 Defines a default value for the IP address of the 2110 default router where packets to other networks are 2111 sent to. 2112 (Environment variable "gatewayip") 2113 2114- Subnet mask: 2115 CONFIG_NETMASK 2116 2117 Defines a default value for the subnet mask (or 2118 routing prefix) which is used to determine if an IP 2119 address belongs to the local subnet or needs to be 2120 forwarded through a router. 2121 (Environment variable "netmask") 2122 2123- Multicast TFTP Mode: 2124 CONFIG_MCAST_TFTP 2125 2126 Defines whether you want to support multicast TFTP as per 2127 rfc-2090; for example to work with atftp. Lets lots of targets 2128 tftp down the same boot image concurrently. Note: the Ethernet 2129 driver in use must provide a function: mcast() to join/leave a 2130 multicast group. 2131 2132- BOOTP Recovery Mode: 2133 CONFIG_BOOTP_RANDOM_DELAY 2134 2135 If you have many targets in a network that try to 2136 boot using BOOTP, you may want to avoid that all 2137 systems send out BOOTP requests at precisely the same 2138 moment (which would happen for instance at recovery 2139 from a power failure, when all systems will try to 2140 boot, thus flooding the BOOTP server. Defining 2141 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 2142 inserted before sending out BOOTP requests. The 2143 following delays are inserted then: 2144 2145 1st BOOTP request: delay 0 ... 1 sec 2146 2nd BOOTP request: delay 0 ... 2 sec 2147 3rd BOOTP request: delay 0 ... 4 sec 2148 4th and following 2149 BOOTP requests: delay 0 ... 8 sec 2150 2151 CONFIG_BOOTP_ID_CACHE_SIZE 2152 2153 BOOTP packets are uniquely identified using a 32-bit ID. The 2154 server will copy the ID from client requests to responses and 2155 U-Boot will use this to determine if it is the destination of 2156 an incoming response. Some servers will check that addresses 2157 aren't in use before handing them out (usually using an ARP 2158 ping) and therefore take up to a few hundred milliseconds to 2159 respond. Network congestion may also influence the time it 2160 takes for a response to make it back to the client. If that 2161 time is too long, U-Boot will retransmit requests. In order 2162 to allow earlier responses to still be accepted after these 2163 retransmissions, U-Boot's BOOTP client keeps a small cache of 2164 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 2165 cache. The default is to keep IDs for up to four outstanding 2166 requests. Increasing this will allow U-Boot to accept offers 2167 from a BOOTP client in networks with unusually high latency. 2168 2169- DHCP Advanced Options: 2170 You can fine tune the DHCP functionality by defining 2171 CONFIG_BOOTP_* symbols: 2172 2173 CONFIG_BOOTP_SUBNETMASK 2174 CONFIG_BOOTP_GATEWAY 2175 CONFIG_BOOTP_HOSTNAME 2176 CONFIG_BOOTP_NISDOMAIN 2177 CONFIG_BOOTP_BOOTPATH 2178 CONFIG_BOOTP_BOOTFILESIZE 2179 CONFIG_BOOTP_DNS 2180 CONFIG_BOOTP_DNS2 2181 CONFIG_BOOTP_SEND_HOSTNAME 2182 CONFIG_BOOTP_NTPSERVER 2183 CONFIG_BOOTP_TIMEOFFSET 2184 CONFIG_BOOTP_VENDOREX 2185 CONFIG_BOOTP_MAY_FAIL 2186 2187 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2188 environment variable, not the BOOTP server. 2189 2190 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2191 after the configured retry count, the call will fail 2192 instead of starting over. This can be used to fail over 2193 to Link-local IP address configuration if the DHCP server 2194 is not available. 2195 2196 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2197 serverip from a DHCP server, it is possible that more 2198 than one DNS serverip is offered to the client. 2199 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2200 serverip will be stored in the additional environment 2201 variable "dnsip2". The first DNS serverip is always 2202 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2203 is defined. 2204 2205 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2206 to do a dynamic update of a DNS server. To do this, they 2207 need the hostname of the DHCP requester. 2208 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2209 of the "hostname" environment variable is passed as 2210 option 12 to the DHCP server. 2211 2212 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2213 2214 A 32bit value in microseconds for a delay between 2215 receiving a "DHCP Offer" and sending the "DHCP Request". 2216 This fixes a problem with certain DHCP servers that don't 2217 respond 100% of the time to a "DHCP request". E.g. On an 2218 AT91RM9200 processor running at 180MHz, this delay needed 2219 to be *at least* 15,000 usec before a Windows Server 2003 2220 DHCP server would reply 100% of the time. I recommend at 2221 least 50,000 usec to be safe. The alternative is to hope 2222 that one of the retries will be successful but note that 2223 the DHCP timeout and retry process takes a longer than 2224 this delay. 2225 2226 - Link-local IP address negotiation: 2227 Negotiate with other link-local clients on the local network 2228 for an address that doesn't require explicit configuration. 2229 This is especially useful if a DHCP server cannot be guaranteed 2230 to exist in all environments that the device must operate. 2231 2232 See doc/README.link-local for more information. 2233 2234 - CDP Options: 2235 CONFIG_CDP_DEVICE_ID 2236 2237 The device id used in CDP trigger frames. 2238 2239 CONFIG_CDP_DEVICE_ID_PREFIX 2240 2241 A two character string which is prefixed to the MAC address 2242 of the device. 2243 2244 CONFIG_CDP_PORT_ID 2245 2246 A printf format string which contains the ascii name of 2247 the port. Normally is set to "eth%d" which sets 2248 eth0 for the first Ethernet, eth1 for the second etc. 2249 2250 CONFIG_CDP_CAPABILITIES 2251 2252 A 32bit integer which indicates the device capabilities; 2253 0x00000010 for a normal host which does not forwards. 2254 2255 CONFIG_CDP_VERSION 2256 2257 An ascii string containing the version of the software. 2258 2259 CONFIG_CDP_PLATFORM 2260 2261 An ascii string containing the name of the platform. 2262 2263 CONFIG_CDP_TRIGGER 2264 2265 A 32bit integer sent on the trigger. 2266 2267 CONFIG_CDP_POWER_CONSUMPTION 2268 2269 A 16bit integer containing the power consumption of the 2270 device in .1 of milliwatts. 2271 2272 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2273 2274 A byte containing the id of the VLAN. 2275 2276- Status LED: CONFIG_STATUS_LED 2277 2278 Several configurations allow to display the current 2279 status using a LED. For instance, the LED will blink 2280 fast while running U-Boot code, stop blinking as 2281 soon as a reply to a BOOTP request was received, and 2282 start blinking slow once the Linux kernel is running 2283 (supported by a status LED driver in the Linux 2284 kernel). Defining CONFIG_STATUS_LED enables this 2285 feature in U-Boot. 2286 2287 Additional options: 2288 2289 CONFIG_GPIO_LED 2290 The status LED can be connected to a GPIO pin. 2291 In such cases, the gpio_led driver can be used as a 2292 status LED backend implementation. Define CONFIG_GPIO_LED 2293 to include the gpio_led driver in the U-Boot binary. 2294 2295 CONFIG_GPIO_LED_INVERTED_TABLE 2296 Some GPIO connected LEDs may have inverted polarity in which 2297 case the GPIO high value corresponds to LED off state and 2298 GPIO low value corresponds to LED on state. 2299 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2300 with a list of GPIO LEDs that have inverted polarity. 2301 2302- CAN Support: CONFIG_CAN_DRIVER 2303 2304 Defining CONFIG_CAN_DRIVER enables CAN driver support 2305 on those systems that support this (optional) 2306 feature, like the TQM8xxL modules. 2307 2308- I2C Support: CONFIG_SYS_I2C 2309 2310 This enable the NEW i2c subsystem, and will allow you to use 2311 i2c commands at the u-boot command line (as long as you set 2312 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2313 based realtime clock chips or other i2c devices. See 2314 common/cmd_i2c.c for a description of the command line 2315 interface. 2316 2317 ported i2c driver to the new framework: 2318 - drivers/i2c/soft_i2c.c: 2319 - activate first bus with CONFIG_SYS_I2C_SOFT define 2320 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2321 for defining speed and slave address 2322 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2323 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2324 for defining speed and slave address 2325 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2326 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2327 for defining speed and slave address 2328 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2329 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2330 for defining speed and slave address 2331 2332 - drivers/i2c/fsl_i2c.c: 2333 - activate i2c driver with CONFIG_SYS_I2C_FSL 2334 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2335 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2336 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2337 bus. 2338 - If your board supports a second fsl i2c bus, define 2339 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2340 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2341 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2342 second bus. 2343 2344 - drivers/i2c/tegra_i2c.c: 2345 - activate this driver with CONFIG_SYS_I2C_TEGRA 2346 - This driver adds 4 i2c buses with a fix speed from 2347 100000 and the slave addr 0! 2348 2349 - drivers/i2c/ppc4xx_i2c.c 2350 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2351 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2352 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2353 2354 - drivers/i2c/i2c_mxc.c 2355 - activate this driver with CONFIG_SYS_I2C_MXC 2356 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2357 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2358 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2359 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2360 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2361 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2362 If those defines are not set, default value is 100000 2363 for speed, and 0 for slave. 2364 2365 - drivers/i2c/rcar_i2c.c: 2366 - activate this driver with CONFIG_SYS_I2C_RCAR 2367 - This driver adds 4 i2c buses 2368 2369 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2370 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2371 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2372 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2373 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2374 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2375 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2376 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2377 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2378 2379 - drivers/i2c/sh_i2c.c: 2380 - activate this driver with CONFIG_SYS_I2C_SH 2381 - This driver adds from 2 to 5 i2c buses 2382 2383 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2384 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2385 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2386 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2387 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2388 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2389 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2390 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2391 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2392 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2393 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2394 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2395 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2396 2397 - drivers/i2c/omap24xx_i2c.c 2398 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2399 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2400 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2401 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2402 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2403 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2404 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2405 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2406 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2407 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2408 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2409 2410 - drivers/i2c/zynq_i2c.c 2411 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2412 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2413 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2414 2415 - drivers/i2c/s3c24x0_i2c.c: 2416 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2417 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2418 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2419 with a fix speed from 100000 and the slave addr 0! 2420 2421 - drivers/i2c/ihs_i2c.c 2422 - activate this driver with CONFIG_SYS_I2C_IHS 2423 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2424 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2425 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2426 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2427 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2428 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2429 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2430 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2431 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2432 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2433 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2434 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2435 2436 additional defines: 2437 2438 CONFIG_SYS_NUM_I2C_BUSES 2439 Hold the number of i2c buses you want to use. If you 2440 don't use/have i2c muxes on your i2c bus, this 2441 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2442 omit this define. 2443 2444 CONFIG_SYS_I2C_DIRECT_BUS 2445 define this, if you don't use i2c muxes on your hardware. 2446 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2447 omit this define. 2448 2449 CONFIG_SYS_I2C_MAX_HOPS 2450 define how many muxes are maximal consecutively connected 2451 on one i2c bus. If you not use i2c muxes, omit this 2452 define. 2453 2454 CONFIG_SYS_I2C_BUSES 2455 hold a list of buses you want to use, only used if 2456 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2457 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2458 CONFIG_SYS_NUM_I2C_BUSES = 9: 2459 2460 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2461 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2462 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2463 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2464 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2465 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2466 {1, {I2C_NULL_HOP}}, \ 2467 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2468 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2469 } 2470 2471 which defines 2472 bus 0 on adapter 0 without a mux 2473 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2474 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2475 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2476 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2477 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2478 bus 6 on adapter 1 without a mux 2479 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2480 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2481 2482 If you do not have i2c muxes on your board, omit this define. 2483 2484- Legacy I2C Support: CONFIG_HARD_I2C 2485 2486 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2487 provides the following compelling advantages: 2488 2489 - more than one i2c adapter is usable 2490 - approved multibus support 2491 - better i2c mux support 2492 2493 ** Please consider updating your I2C driver now. ** 2494 2495 These enable legacy I2C serial bus commands. Defining 2496 CONFIG_HARD_I2C will include the appropriate I2C driver 2497 for the selected CPU. 2498 2499 This will allow you to use i2c commands at the u-boot 2500 command line (as long as you set CONFIG_CMD_I2C in 2501 CONFIG_COMMANDS) and communicate with i2c based realtime 2502 clock chips. See common/cmd_i2c.c for a description of the 2503 command line interface. 2504 2505 CONFIG_HARD_I2C selects a hardware I2C controller. 2506 2507 There are several other quantities that must also be 2508 defined when you define CONFIG_HARD_I2C. 2509 2510 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2511 to be the frequency (in Hz) at which you wish your i2c bus 2512 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2513 the CPU's i2c node address). 2514 2515 Now, the u-boot i2c code for the mpc8xx 2516 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2517 and so its address should therefore be cleared to 0 (See, 2518 eg, MPC823e User's Manual p.16-473). So, set 2519 CONFIG_SYS_I2C_SLAVE to 0. 2520 2521 CONFIG_SYS_I2C_INIT_MPC5XXX 2522 2523 When a board is reset during an i2c bus transfer 2524 chips might think that the current transfer is still 2525 in progress. Reset the slave devices by sending start 2526 commands until the slave device responds. 2527 2528 That's all that's required for CONFIG_HARD_I2C. 2529 2530 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2531 then the following macros need to be defined (examples are 2532 from include/configs/lwmon.h): 2533 2534 I2C_INIT 2535 2536 (Optional). Any commands necessary to enable the I2C 2537 controller or configure ports. 2538 2539 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2540 2541 I2C_PORT 2542 2543 (Only for MPC8260 CPU). The I/O port to use (the code 2544 assumes both bits are on the same port). Valid values 2545 are 0..3 for ports A..D. 2546 2547 I2C_ACTIVE 2548 2549 The code necessary to make the I2C data line active 2550 (driven). If the data line is open collector, this 2551 define can be null. 2552 2553 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2554 2555 I2C_TRISTATE 2556 2557 The code necessary to make the I2C data line tri-stated 2558 (inactive). If the data line is open collector, this 2559 define can be null. 2560 2561 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2562 2563 I2C_READ 2564 2565 Code that returns true if the I2C data line is high, 2566 false if it is low. 2567 2568 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2569 2570 I2C_SDA(bit) 2571 2572 If <bit> is true, sets the I2C data line high. If it 2573 is false, it clears it (low). 2574 2575 eg: #define I2C_SDA(bit) \ 2576 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2577 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2578 2579 I2C_SCL(bit) 2580 2581 If <bit> is true, sets the I2C clock line high. If it 2582 is false, it clears it (low). 2583 2584 eg: #define I2C_SCL(bit) \ 2585 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2586 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2587 2588 I2C_DELAY 2589 2590 This delay is invoked four times per clock cycle so this 2591 controls the rate of data transfer. The data rate thus 2592 is 1 / (I2C_DELAY * 4). Often defined to be something 2593 like: 2594 2595 #define I2C_DELAY udelay(2) 2596 2597 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2598 2599 If your arch supports the generic GPIO framework (asm/gpio.h), 2600 then you may alternatively define the two GPIOs that are to be 2601 used as SCL / SDA. Any of the previous I2C_xxx macros will 2602 have GPIO-based defaults assigned to them as appropriate. 2603 2604 You should define these to the GPIO value as given directly to 2605 the generic GPIO functions. 2606 2607 CONFIG_SYS_I2C_INIT_BOARD 2608 2609 When a board is reset during an i2c bus transfer 2610 chips might think that the current transfer is still 2611 in progress. On some boards it is possible to access 2612 the i2c SCLK line directly, either by using the 2613 processor pin as a GPIO or by having a second pin 2614 connected to the bus. If this option is defined a 2615 custom i2c_init_board() routine in boards/xxx/board.c 2616 is run early in the boot sequence. 2617 2618 CONFIG_SYS_I2C_BOARD_LATE_INIT 2619 2620 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2621 defined a custom i2c_board_late_init() routine in 2622 boards/xxx/board.c is run AFTER the operations in i2c_init() 2623 is completed. This callpoint can be used to unreset i2c bus 2624 using CPU i2c controller register accesses for CPUs whose i2c 2625 controller provide such a method. It is called at the end of 2626 i2c_init() to allow i2c_init operations to setup the i2c bus 2627 controller on the CPU (e.g. setting bus speed & slave address). 2628 2629 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2630 2631 This option enables configuration of bi_iic_fast[] flags 2632 in u-boot bd_info structure based on u-boot environment 2633 variable "i2cfast". (see also i2cfast) 2634 2635 CONFIG_I2C_MULTI_BUS 2636 2637 This option allows the use of multiple I2C buses, each of which 2638 must have a controller. At any point in time, only one bus is 2639 active. To switch to a different bus, use the 'i2c dev' command. 2640 Note that bus numbering is zero-based. 2641 2642 CONFIG_SYS_I2C_NOPROBES 2643 2644 This option specifies a list of I2C devices that will be skipped 2645 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2646 is set, specify a list of bus-device pairs. Otherwise, specify 2647 a 1D array of device addresses 2648 2649 e.g. 2650 #undef CONFIG_I2C_MULTI_BUS 2651 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2652 2653 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2654 2655 #define CONFIG_I2C_MULTI_BUS 2656 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2657 2658 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2659 2660 CONFIG_SYS_SPD_BUS_NUM 2661 2662 If defined, then this indicates the I2C bus number for DDR SPD. 2663 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2664 2665 CONFIG_SYS_RTC_BUS_NUM 2666 2667 If defined, then this indicates the I2C bus number for the RTC. 2668 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2669 2670 CONFIG_SYS_DTT_BUS_NUM 2671 2672 If defined, then this indicates the I2C bus number for the DTT. 2673 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2674 2675 CONFIG_SYS_I2C_DTT_ADDR: 2676 2677 If defined, specifies the I2C address of the DTT device. 2678 If not defined, then U-Boot uses predefined value for 2679 specified DTT device. 2680 2681 CONFIG_SOFT_I2C_READ_REPEATED_START 2682 2683 defining this will force the i2c_read() function in 2684 the soft_i2c driver to perform an I2C repeated start 2685 between writing the address pointer and reading the 2686 data. If this define is omitted the default behaviour 2687 of doing a stop-start sequence will be used. Most I2C 2688 devices can use either method, but some require one or 2689 the other. 2690 2691- SPI Support: CONFIG_SPI 2692 2693 Enables SPI driver (so far only tested with 2694 SPI EEPROM, also an instance works with Crystal A/D and 2695 D/As on the SACSng board) 2696 2697 CONFIG_SH_SPI 2698 2699 Enables the driver for SPI controller on SuperH. Currently 2700 only SH7757 is supported. 2701 2702 CONFIG_SPI_X 2703 2704 Enables extended (16-bit) SPI EEPROM addressing. 2705 (symmetrical to CONFIG_I2C_X) 2706 2707 CONFIG_SOFT_SPI 2708 2709 Enables a software (bit-bang) SPI driver rather than 2710 using hardware support. This is a general purpose 2711 driver that only requires three general I/O port pins 2712 (two outputs, one input) to function. If this is 2713 defined, the board configuration must define several 2714 SPI configuration items (port pins to use, etc). For 2715 an example, see include/configs/sacsng.h. 2716 2717 CONFIG_HARD_SPI 2718 2719 Enables a hardware SPI driver for general-purpose reads 2720 and writes. As with CONFIG_SOFT_SPI, the board configuration 2721 must define a list of chip-select function pointers. 2722 Currently supported on some MPC8xxx processors. For an 2723 example, see include/configs/mpc8349emds.h. 2724 2725 CONFIG_MXC_SPI 2726 2727 Enables the driver for the SPI controllers on i.MX and MXC 2728 SoCs. Currently i.MX31/35/51 are supported. 2729 2730 CONFIG_SYS_SPI_MXC_WAIT 2731 Timeout for waiting until spi transfer completed. 2732 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2733 2734- FPGA Support: CONFIG_FPGA 2735 2736 Enables FPGA subsystem. 2737 2738 CONFIG_FPGA_<vendor> 2739 2740 Enables support for specific chip vendors. 2741 (ALTERA, XILINX) 2742 2743 CONFIG_FPGA_<family> 2744 2745 Enables support for FPGA family. 2746 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2747 2748 CONFIG_FPGA_COUNT 2749 2750 Specify the number of FPGA devices to support. 2751 2752 CONFIG_CMD_FPGA_LOADMK 2753 2754 Enable support for fpga loadmk command 2755 2756 CONFIG_CMD_FPGA_LOADP 2757 2758 Enable support for fpga loadp command - load partial bitstream 2759 2760 CONFIG_CMD_FPGA_LOADBP 2761 2762 Enable support for fpga loadbp command - load partial bitstream 2763 (Xilinx only) 2764 2765 CONFIG_SYS_FPGA_PROG_FEEDBACK 2766 2767 Enable printing of hash marks during FPGA configuration. 2768 2769 CONFIG_SYS_FPGA_CHECK_BUSY 2770 2771 Enable checks on FPGA configuration interface busy 2772 status by the configuration function. This option 2773 will require a board or device specific function to 2774 be written. 2775 2776 CONFIG_FPGA_DELAY 2777 2778 If defined, a function that provides delays in the FPGA 2779 configuration driver. 2780 2781 CONFIG_SYS_FPGA_CHECK_CTRLC 2782 Allow Control-C to interrupt FPGA configuration 2783 2784 CONFIG_SYS_FPGA_CHECK_ERROR 2785 2786 Check for configuration errors during FPGA bitfile 2787 loading. For example, abort during Virtex II 2788 configuration if the INIT_B line goes low (which 2789 indicated a CRC error). 2790 2791 CONFIG_SYS_FPGA_WAIT_INIT 2792 2793 Maximum time to wait for the INIT_B line to de-assert 2794 after PROB_B has been de-asserted during a Virtex II 2795 FPGA configuration sequence. The default time is 500 2796 ms. 2797 2798 CONFIG_SYS_FPGA_WAIT_BUSY 2799 2800 Maximum time to wait for BUSY to de-assert during 2801 Virtex II FPGA configuration. The default is 5 ms. 2802 2803 CONFIG_SYS_FPGA_WAIT_CONFIG 2804 2805 Time to wait after FPGA configuration. The default is 2806 200 ms. 2807 2808- Configuration Management: 2809 CONFIG_BUILD_TARGET 2810 2811 Some SoCs need special image types (e.g. U-Boot binary 2812 with a special header) as build targets. By defining 2813 CONFIG_BUILD_TARGET in the SoC / board header, this 2814 special image will be automatically built upon calling 2815 make / MAKEALL. 2816 2817 CONFIG_IDENT_STRING 2818 2819 If defined, this string will be added to the U-Boot 2820 version information (U_BOOT_VERSION) 2821 2822- Vendor Parameter Protection: 2823 2824 U-Boot considers the values of the environment 2825 variables "serial#" (Board Serial Number) and 2826 "ethaddr" (Ethernet Address) to be parameters that 2827 are set once by the board vendor / manufacturer, and 2828 protects these variables from casual modification by 2829 the user. Once set, these variables are read-only, 2830 and write or delete attempts are rejected. You can 2831 change this behaviour: 2832 2833 If CONFIG_ENV_OVERWRITE is #defined in your config 2834 file, the write protection for vendor parameters is 2835 completely disabled. Anybody can change or delete 2836 these parameters. 2837 2838 Alternatively, if you #define _both_ CONFIG_ETHADDR 2839 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2840 Ethernet address is installed in the environment, 2841 which can be changed exactly ONCE by the user. [The 2842 serial# is unaffected by this, i. e. it remains 2843 read-only.] 2844 2845 The same can be accomplished in a more flexible way 2846 for any variable by configuring the type of access 2847 to allow for those variables in the ".flags" variable 2848 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2849 2850- Protected RAM: 2851 CONFIG_PRAM 2852 2853 Define this variable to enable the reservation of 2854 "protected RAM", i. e. RAM which is not overwritten 2855 by U-Boot. Define CONFIG_PRAM to hold the number of 2856 kB you want to reserve for pRAM. You can overwrite 2857 this default value by defining an environment 2858 variable "pram" to the number of kB you want to 2859 reserve. Note that the board info structure will 2860 still show the full amount of RAM. If pRAM is 2861 reserved, a new environment variable "mem" will 2862 automatically be defined to hold the amount of 2863 remaining RAM in a form that can be passed as boot 2864 argument to Linux, for instance like that: 2865 2866 setenv bootargs ... mem=\${mem} 2867 saveenv 2868 2869 This way you can tell Linux not to use this memory, 2870 either, which results in a memory region that will 2871 not be affected by reboots. 2872 2873 *WARNING* If your board configuration uses automatic 2874 detection of the RAM size, you must make sure that 2875 this memory test is non-destructive. So far, the 2876 following board configurations are known to be 2877 "pRAM-clean": 2878 2879 IVMS8, IVML24, SPD8xx, TQM8xxL, 2880 HERMES, IP860, RPXlite, LWMON, 2881 FLAGADM, TQM8260 2882 2883- Access to physical memory region (> 4GB) 2884 Some basic support is provided for operations on memory not 2885 normally accessible to U-Boot - e.g. some architectures 2886 support access to more than 4GB of memory on 32-bit 2887 machines using physical address extension or similar. 2888 Define CONFIG_PHYSMEM to access this basic support, which 2889 currently only supports clearing the memory. 2890 2891- Error Recovery: 2892 CONFIG_PANIC_HANG 2893 2894 Define this variable to stop the system in case of a 2895 fatal error, so that you have to reset it manually. 2896 This is probably NOT a good idea for an embedded 2897 system where you want the system to reboot 2898 automatically as fast as possible, but it may be 2899 useful during development since you can try to debug 2900 the conditions that lead to the situation. 2901 2902 CONFIG_NET_RETRY_COUNT 2903 2904 This variable defines the number of retries for 2905 network operations like ARP, RARP, TFTP, or BOOTP 2906 before giving up the operation. If not defined, a 2907 default value of 5 is used. 2908 2909 CONFIG_ARP_TIMEOUT 2910 2911 Timeout waiting for an ARP reply in milliseconds. 2912 2913 CONFIG_NFS_TIMEOUT 2914 2915 Timeout in milliseconds used in NFS protocol. 2916 If you encounter "ERROR: Cannot umount" in nfs command, 2917 try longer timeout such as 2918 #define CONFIG_NFS_TIMEOUT 10000UL 2919 2920- Command Interpreter: 2921 CONFIG_AUTO_COMPLETE 2922 2923 Enable auto completion of commands using TAB. 2924 2925 CONFIG_SYS_PROMPT_HUSH_PS2 2926 2927 This defines the secondary prompt string, which is 2928 printed when the command interpreter needs more input 2929 to complete a command. Usually "> ". 2930 2931 Note: 2932 2933 In the current implementation, the local variables 2934 space and global environment variables space are 2935 separated. Local variables are those you define by 2936 simply typing `name=value'. To access a local 2937 variable later on, you have write `$name' or 2938 `${name}'; to execute the contents of a variable 2939 directly type `$name' at the command prompt. 2940 2941 Global environment variables are those you use 2942 setenv/printenv to work with. To run a command stored 2943 in such a variable, you need to use the run command, 2944 and you must not use the '$' sign to access them. 2945 2946 To store commands and special characters in a 2947 variable, please use double quotation marks 2948 surrounding the whole text of the variable, instead 2949 of the backslashes before semicolons and special 2950 symbols. 2951 2952- Command Line Editing and History: 2953 CONFIG_CMDLINE_EDITING 2954 2955 Enable editing and History functions for interactive 2956 command line input operations 2957 2958- Default Environment: 2959 CONFIG_EXTRA_ENV_SETTINGS 2960 2961 Define this to contain any number of null terminated 2962 strings (variable = value pairs) that will be part of 2963 the default environment compiled into the boot image. 2964 2965 For example, place something like this in your 2966 board's config file: 2967 2968 #define CONFIG_EXTRA_ENV_SETTINGS \ 2969 "myvar1=value1\0" \ 2970 "myvar2=value2\0" 2971 2972 Warning: This method is based on knowledge about the 2973 internal format how the environment is stored by the 2974 U-Boot code. This is NOT an official, exported 2975 interface! Although it is unlikely that this format 2976 will change soon, there is no guarantee either. 2977 You better know what you are doing here. 2978 2979 Note: overly (ab)use of the default environment is 2980 discouraged. Make sure to check other ways to preset 2981 the environment like the "source" command or the 2982 boot command first. 2983 2984 CONFIG_ENV_VARS_UBOOT_CONFIG 2985 2986 Define this in order to add variables describing the 2987 U-Boot build configuration to the default environment. 2988 These will be named arch, cpu, board, vendor, and soc. 2989 2990 Enabling this option will cause the following to be defined: 2991 2992 - CONFIG_SYS_ARCH 2993 - CONFIG_SYS_CPU 2994 - CONFIG_SYS_BOARD 2995 - CONFIG_SYS_VENDOR 2996 - CONFIG_SYS_SOC 2997 2998 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2999 3000 Define this in order to add variables describing certain 3001 run-time determined information about the hardware to the 3002 environment. These will be named board_name, board_rev. 3003 3004 CONFIG_DELAY_ENVIRONMENT 3005 3006 Normally the environment is loaded when the board is 3007 initialised so that it is available to U-Boot. This inhibits 3008 that so that the environment is not available until 3009 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 3010 this is instead controlled by the value of 3011 /config/load-environment. 3012 3013- DataFlash Support: 3014 CONFIG_HAS_DATAFLASH 3015 3016 Defining this option enables DataFlash features and 3017 allows to read/write in Dataflash via the standard 3018 commands cp, md... 3019 3020- Serial Flash support 3021 CONFIG_CMD_SF 3022 3023 Defining this option enables SPI flash commands 3024 'sf probe/read/write/erase/update'. 3025 3026 Usage requires an initial 'probe' to define the serial 3027 flash parameters, followed by read/write/erase/update 3028 commands. 3029 3030 The following defaults may be provided by the platform 3031 to handle the common case when only a single serial 3032 flash is present on the system. 3033 3034 CONFIG_SF_DEFAULT_BUS Bus identifier 3035 CONFIG_SF_DEFAULT_CS Chip-select 3036 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 3037 CONFIG_SF_DEFAULT_SPEED in Hz 3038 3039 CONFIG_CMD_SF_TEST 3040 3041 Define this option to include a destructive SPI flash 3042 test ('sf test'). 3043 3044 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg 3045 3046 Define this option to use the Bank addr/Extended addr 3047 support on SPI flashes which has size > 16Mbytes. 3048 3049 CONFIG_SF_DUAL_FLASH Dual flash memories 3050 3051 Define this option to use dual flash support where two flash 3052 memories can be connected with a given cs line. 3053 Currently Xilinx Zynq qspi supports these type of connections. 3054 3055 CONFIG_SYS_SPI_ST_ENABLE_WP_PIN 3056 enable the W#/Vpp signal to disable writing to the status 3057 register on ST MICRON flashes like the N25Q128. 3058 The status register write enable/disable bit, combined with 3059 the W#/VPP signal provides hardware data protection for the 3060 device as follows: When the enable/disable bit is set to 1, 3061 and the W#/VPP signal is driven LOW, the status register 3062 nonvolatile bits become read-only and the WRITE STATUS REGISTER 3063 operation will not execute. The only way to exit this 3064 hardware-protected mode is to drive W#/VPP HIGH. 3065 3066- SystemACE Support: 3067 CONFIG_SYSTEMACE 3068 3069 Adding this option adds support for Xilinx SystemACE 3070 chips attached via some sort of local bus. The address 3071 of the chip must also be defined in the 3072 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 3073 3074 #define CONFIG_SYSTEMACE 3075 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 3076 3077 When SystemACE support is added, the "ace" device type 3078 becomes available to the fat commands, i.e. fatls. 3079 3080- TFTP Fixed UDP Port: 3081 CONFIG_TFTP_PORT 3082 3083 If this is defined, the environment variable tftpsrcp 3084 is used to supply the TFTP UDP source port value. 3085 If tftpsrcp isn't defined, the normal pseudo-random port 3086 number generator is used. 3087 3088 Also, the environment variable tftpdstp is used to supply 3089 the TFTP UDP destination port value. If tftpdstp isn't 3090 defined, the normal port 69 is used. 3091 3092 The purpose for tftpsrcp is to allow a TFTP server to 3093 blindly start the TFTP transfer using the pre-configured 3094 target IP address and UDP port. This has the effect of 3095 "punching through" the (Windows XP) firewall, allowing 3096 the remainder of the TFTP transfer to proceed normally. 3097 A better solution is to properly configure the firewall, 3098 but sometimes that is not allowed. 3099 3100- Hashing support: 3101 CONFIG_CMD_HASH 3102 3103 This enables a generic 'hash' command which can produce 3104 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 3105 3106 CONFIG_HASH_VERIFY 3107 3108 Enable the hash verify command (hash -v). This adds to code 3109 size a little. 3110 3111 CONFIG_SHA1 - This option enables support of hashing using SHA1 3112 algorithm. The hash is calculated in software. 3113 CONFIG_SHA256 - This option enables support of hashing using 3114 SHA256 algorithm. The hash is calculated in software. 3115 CONFIG_SHA_HW_ACCEL - This option enables hardware acceleration 3116 for SHA1/SHA256 hashing. 3117 This affects the 'hash' command and also the 3118 hash_lookup_algo() function. 3119 CONFIG_SHA_PROG_HW_ACCEL - This option enables 3120 hardware-acceleration for SHA1/SHA256 progressive hashing. 3121 Data can be streamed in a block at a time and the hashing 3122 is performed in hardware. 3123 3124 Note: There is also a sha1sum command, which should perhaps 3125 be deprecated in favour of 'hash sha1'. 3126 3127- Freescale i.MX specific commands: 3128 CONFIG_CMD_HDMIDETECT 3129 This enables 'hdmidet' command which returns true if an 3130 HDMI monitor is detected. This command is i.MX 6 specific. 3131 3132 CONFIG_CMD_BMODE 3133 This enables the 'bmode' (bootmode) command for forcing 3134 a boot from specific media. 3135 3136 This is useful for forcing the ROM's usb downloader to 3137 activate upon a watchdog reset which is nice when iterating 3138 on U-Boot. Using the reset button or running bmode normal 3139 will set it back to normal. This command currently 3140 supports i.MX53 and i.MX6. 3141 3142- Signing support: 3143 CONFIG_RSA 3144 3145 This enables the RSA algorithm used for FIT image verification 3146 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 3147 3148 The Modular Exponentiation algorithm in RSA is implemented using 3149 driver model. So CONFIG_DM needs to be enabled by default for this 3150 library to function. 3151 3152 The signing part is build into mkimage regardless of this 3153 option. The software based modular exponentiation is built into 3154 mkimage irrespective of this option. 3155 3156- bootcount support: 3157 CONFIG_BOOTCOUNT_LIMIT 3158 3159 This enables the bootcounter support, see: 3160 http://www.denx.de/wiki/DULG/UBootBootCountLimit 3161 3162 CONFIG_AT91SAM9XE 3163 enable special bootcounter support on at91sam9xe based boards. 3164 CONFIG_BLACKFIN 3165 enable special bootcounter support on blackfin based boards. 3166 CONFIG_SOC_DA8XX 3167 enable special bootcounter support on da850 based boards. 3168 CONFIG_BOOTCOUNT_RAM 3169 enable support for the bootcounter in RAM 3170 CONFIG_BOOTCOUNT_I2C 3171 enable support for the bootcounter on an i2c (like RTC) device. 3172 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 3173 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 3174 the bootcounter. 3175 CONFIG_BOOTCOUNT_ALEN = address len 3176 3177- Show boot progress: 3178 CONFIG_SHOW_BOOT_PROGRESS 3179 3180 Defining this option allows to add some board- 3181 specific code (calling a user-provided function 3182 "show_boot_progress(int)") that enables you to show 3183 the system's boot progress on some display (for 3184 example, some LED's) on your board. At the moment, 3185 the following checkpoints are implemented: 3186 3187- Detailed boot stage timing 3188 CONFIG_BOOTSTAGE 3189 Define this option to get detailed timing of each stage 3190 of the boot process. 3191 3192 CONFIG_BOOTSTAGE_USER_COUNT 3193 This is the number of available user bootstage records. 3194 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 3195 a new ID will be allocated from this stash. If you exceed 3196 the limit, recording will stop. 3197 3198 CONFIG_BOOTSTAGE_REPORT 3199 Define this to print a report before boot, similar to this: 3200 3201 Timer summary in microseconds: 3202 Mark Elapsed Stage 3203 0 0 reset 3204 3,575,678 3,575,678 board_init_f start 3205 3,575,695 17 arch_cpu_init A9 3206 3,575,777 82 arch_cpu_init done 3207 3,659,598 83,821 board_init_r start 3208 3,910,375 250,777 main_loop 3209 29,916,167 26,005,792 bootm_start 3210 30,361,327 445,160 start_kernel 3211 3212 CONFIG_CMD_BOOTSTAGE 3213 Add a 'bootstage' command which supports printing a report 3214 and un/stashing of bootstage data. 3215 3216 CONFIG_BOOTSTAGE_FDT 3217 Stash the bootstage information in the FDT. A root 'bootstage' 3218 node is created with each bootstage id as a child. Each child 3219 has a 'name' property and either 'mark' containing the 3220 mark time in microsecond, or 'accum' containing the 3221 accumulated time for that bootstage id in microseconds. 3222 For example: 3223 3224 bootstage { 3225 154 { 3226 name = "board_init_f"; 3227 mark = <3575678>; 3228 }; 3229 170 { 3230 name = "lcd"; 3231 accum = <33482>; 3232 }; 3233 }; 3234 3235 Code in the Linux kernel can find this in /proc/devicetree. 3236 3237Legacy uImage format: 3238 3239 Arg Where When 3240 1 common/cmd_bootm.c before attempting to boot an image 3241 -1 common/cmd_bootm.c Image header has bad magic number 3242 2 common/cmd_bootm.c Image header has correct magic number 3243 -2 common/cmd_bootm.c Image header has bad checksum 3244 3 common/cmd_bootm.c Image header has correct checksum 3245 -3 common/cmd_bootm.c Image data has bad checksum 3246 4 common/cmd_bootm.c Image data has correct checksum 3247 -4 common/cmd_bootm.c Image is for unsupported architecture 3248 5 common/cmd_bootm.c Architecture check OK 3249 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3250 6 common/cmd_bootm.c Image Type check OK 3251 -6 common/cmd_bootm.c gunzip uncompression error 3252 -7 common/cmd_bootm.c Unimplemented compression type 3253 7 common/cmd_bootm.c Uncompression OK 3254 8 common/cmd_bootm.c No uncompress/copy overwrite error 3255 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3256 3257 9 common/image.c Start initial ramdisk verification 3258 -10 common/image.c Ramdisk header has bad magic number 3259 -11 common/image.c Ramdisk header has bad checksum 3260 10 common/image.c Ramdisk header is OK 3261 -12 common/image.c Ramdisk data has bad checksum 3262 11 common/image.c Ramdisk data has correct checksum 3263 12 common/image.c Ramdisk verification complete, start loading 3264 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3265 13 common/image.c Start multifile image verification 3266 14 common/image.c No initial ramdisk, no multifile, continue. 3267 3268 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3269 3270 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3271 -31 post/post.c POST test failed, detected by post_output_backlog() 3272 -32 post/post.c POST test failed, detected by post_run_single() 3273 3274 34 common/cmd_doc.c before loading a Image from a DOC device 3275 -35 common/cmd_doc.c Bad usage of "doc" command 3276 35 common/cmd_doc.c correct usage of "doc" command 3277 -36 common/cmd_doc.c No boot device 3278 36 common/cmd_doc.c correct boot device 3279 -37 common/cmd_doc.c Unknown Chip ID on boot device 3280 37 common/cmd_doc.c correct chip ID found, device available 3281 -38 common/cmd_doc.c Read Error on boot device 3282 38 common/cmd_doc.c reading Image header from DOC device OK 3283 -39 common/cmd_doc.c Image header has bad magic number 3284 39 common/cmd_doc.c Image header has correct magic number 3285 -40 common/cmd_doc.c Error reading Image from DOC device 3286 40 common/cmd_doc.c Image header has correct magic number 3287 41 common/cmd_ide.c before loading a Image from a IDE device 3288 -42 common/cmd_ide.c Bad usage of "ide" command 3289 42 common/cmd_ide.c correct usage of "ide" command 3290 -43 common/cmd_ide.c No boot device 3291 43 common/cmd_ide.c boot device found 3292 -44 common/cmd_ide.c Device not available 3293 44 common/cmd_ide.c Device available 3294 -45 common/cmd_ide.c wrong partition selected 3295 45 common/cmd_ide.c partition selected 3296 -46 common/cmd_ide.c Unknown partition table 3297 46 common/cmd_ide.c valid partition table found 3298 -47 common/cmd_ide.c Invalid partition type 3299 47 common/cmd_ide.c correct partition type 3300 -48 common/cmd_ide.c Error reading Image Header on boot device 3301 48 common/cmd_ide.c reading Image Header from IDE device OK 3302 -49 common/cmd_ide.c Image header has bad magic number 3303 49 common/cmd_ide.c Image header has correct magic number 3304 -50 common/cmd_ide.c Image header has bad checksum 3305 50 common/cmd_ide.c Image header has correct checksum 3306 -51 common/cmd_ide.c Error reading Image from IDE device 3307 51 common/cmd_ide.c reading Image from IDE device OK 3308 52 common/cmd_nand.c before loading a Image from a NAND device 3309 -53 common/cmd_nand.c Bad usage of "nand" command 3310 53 common/cmd_nand.c correct usage of "nand" command 3311 -54 common/cmd_nand.c No boot device 3312 54 common/cmd_nand.c boot device found 3313 -55 common/cmd_nand.c Unknown Chip ID on boot device 3314 55 common/cmd_nand.c correct chip ID found, device available 3315 -56 common/cmd_nand.c Error reading Image Header on boot device 3316 56 common/cmd_nand.c reading Image Header from NAND device OK 3317 -57 common/cmd_nand.c Image header has bad magic number 3318 57 common/cmd_nand.c Image header has correct magic number 3319 -58 common/cmd_nand.c Error reading Image from NAND device 3320 58 common/cmd_nand.c reading Image from NAND device OK 3321 3322 -60 common/env_common.c Environment has a bad CRC, using default 3323 3324 64 net/eth.c starting with Ethernet configuration. 3325 -64 net/eth.c no Ethernet found. 3326 65 net/eth.c Ethernet found. 3327 3328 -80 common/cmd_net.c usage wrong 3329 80 common/cmd_net.c before calling NetLoop() 3330 -81 common/cmd_net.c some error in NetLoop() occurred 3331 81 common/cmd_net.c NetLoop() back without error 3332 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3333 82 common/cmd_net.c trying automatic boot 3334 83 common/cmd_net.c running "source" command 3335 -83 common/cmd_net.c some error in automatic boot or "source" command 3336 84 common/cmd_net.c end without errors 3337 3338FIT uImage format: 3339 3340 Arg Where When 3341 100 common/cmd_bootm.c Kernel FIT Image has correct format 3342 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3343 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3344 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3345 102 common/cmd_bootm.c Kernel unit name specified 3346 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3347 103 common/cmd_bootm.c Found configuration node 3348 104 common/cmd_bootm.c Got kernel subimage node offset 3349 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3350 105 common/cmd_bootm.c Kernel subimage hash verification OK 3351 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3352 106 common/cmd_bootm.c Architecture check OK 3353 -106 common/cmd_bootm.c Kernel subimage has wrong type 3354 107 common/cmd_bootm.c Kernel subimage type OK 3355 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3356 108 common/cmd_bootm.c Got kernel subimage data/size 3357 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3358 -109 common/cmd_bootm.c Can't get kernel subimage type 3359 -110 common/cmd_bootm.c Can't get kernel subimage comp 3360 -111 common/cmd_bootm.c Can't get kernel subimage os 3361 -112 common/cmd_bootm.c Can't get kernel subimage load address 3362 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3363 3364 120 common/image.c Start initial ramdisk verification 3365 -120 common/image.c Ramdisk FIT image has incorrect format 3366 121 common/image.c Ramdisk FIT image has correct format 3367 122 common/image.c No ramdisk subimage unit name, using configuration 3368 -122 common/image.c Can't get configuration for ramdisk subimage 3369 123 common/image.c Ramdisk unit name specified 3370 -124 common/image.c Can't get ramdisk subimage node offset 3371 125 common/image.c Got ramdisk subimage node offset 3372 -125 common/image.c Ramdisk subimage hash verification failed 3373 126 common/image.c Ramdisk subimage hash verification OK 3374 -126 common/image.c Ramdisk subimage for unsupported architecture 3375 127 common/image.c Architecture check OK 3376 -127 common/image.c Can't get ramdisk subimage data/size 3377 128 common/image.c Got ramdisk subimage data/size 3378 129 common/image.c Can't get ramdisk load address 3379 -129 common/image.c Got ramdisk load address 3380 3381 -130 common/cmd_doc.c Incorrect FIT image format 3382 131 common/cmd_doc.c FIT image format OK 3383 3384 -140 common/cmd_ide.c Incorrect FIT image format 3385 141 common/cmd_ide.c FIT image format OK 3386 3387 -150 common/cmd_nand.c Incorrect FIT image format 3388 151 common/cmd_nand.c FIT image format OK 3389 3390- legacy image format: 3391 CONFIG_IMAGE_FORMAT_LEGACY 3392 enables the legacy image format support in U-Boot. 3393 3394 Default: 3395 enabled if CONFIG_FIT_SIGNATURE is not defined. 3396 3397 CONFIG_DISABLE_IMAGE_LEGACY 3398 disable the legacy image format 3399 3400 This define is introduced, as the legacy image format is 3401 enabled per default for backward compatibility. 3402 3403- FIT image support: 3404 CONFIG_FIT 3405 Enable support for the FIT uImage format. 3406 3407 CONFIG_FIT_BEST_MATCH 3408 When no configuration is explicitly selected, default to the 3409 one whose fdt's compatibility field best matches that of 3410 U-Boot itself. A match is considered "best" if it matches the 3411 most specific compatibility entry of U-Boot's fdt's root node. 3412 The order of entries in the configuration's fdt is ignored. 3413 3414 CONFIG_FIT_SIGNATURE 3415 This option enables signature verification of FIT uImages, 3416 using a hash signed and verified using RSA. If 3417 CONFIG_SHA_PROG_HW_ACCEL is defined, i.e support for progressive 3418 hashing is available using hardware, RSA library will use it. 3419 See doc/uImage.FIT/signature.txt for more details. 3420 3421 WARNING: When relying on signed FIT images with required 3422 signature check the legacy image format is default 3423 disabled. If a board need legacy image format support 3424 enable this through CONFIG_IMAGE_FORMAT_LEGACY 3425 3426 CONFIG_FIT_DISABLE_SHA256 3427 Supporting SHA256 hashes has quite an impact on binary size. 3428 For constrained systems sha256 hash support can be disabled 3429 with this option. 3430 3431- Standalone program support: 3432 CONFIG_STANDALONE_LOAD_ADDR 3433 3434 This option defines a board specific value for the 3435 address where standalone program gets loaded, thus 3436 overwriting the architecture dependent default 3437 settings. 3438 3439- Frame Buffer Address: 3440 CONFIG_FB_ADDR 3441 3442 Define CONFIG_FB_ADDR if you want to use specific 3443 address for frame buffer. This is typically the case 3444 when using a graphics controller has separate video 3445 memory. U-Boot will then place the frame buffer at 3446 the given address instead of dynamically reserving it 3447 in system RAM by calling lcd_setmem(), which grabs 3448 the memory for the frame buffer depending on the 3449 configured panel size. 3450 3451 Please see board_init_f function. 3452 3453- Automatic software updates via TFTP server 3454 CONFIG_UPDATE_TFTP 3455 CONFIG_UPDATE_TFTP_CNT_MAX 3456 CONFIG_UPDATE_TFTP_MSEC_MAX 3457 3458 These options enable and control the auto-update feature; 3459 for a more detailed description refer to doc/README.update. 3460 3461- MTD Support (mtdparts command, UBI support) 3462 CONFIG_MTD_DEVICE 3463 3464 Adds the MTD device infrastructure from the Linux kernel. 3465 Needed for mtdparts command support. 3466 3467 CONFIG_MTD_PARTITIONS 3468 3469 Adds the MTD partitioning infrastructure from the Linux 3470 kernel. Needed for UBI support. 3471 3472 CONFIG_MTD_NAND_VERIFY_WRITE 3473 verify if the written data is correct reread. 3474 3475- UBI support 3476 CONFIG_CMD_UBI 3477 3478 Adds commands for interacting with MTD partitions formatted 3479 with the UBI flash translation layer 3480 3481 Requires also defining CONFIG_RBTREE 3482 3483 CONFIG_UBI_SILENCE_MSG 3484 3485 Make the verbose messages from UBI stop printing. This leaves 3486 warnings and errors enabled. 3487 3488 3489 CONFIG_MTD_UBI_WL_THRESHOLD 3490 This parameter defines the maximum difference between the highest 3491 erase counter value and the lowest erase counter value of eraseblocks 3492 of UBI devices. When this threshold is exceeded, UBI starts performing 3493 wear leveling by means of moving data from eraseblock with low erase 3494 counter to eraseblocks with high erase counter. 3495 3496 The default value should be OK for SLC NAND flashes, NOR flashes and 3497 other flashes which have eraseblock life-cycle 100000 or more. 3498 However, in case of MLC NAND flashes which typically have eraseblock 3499 life-cycle less than 10000, the threshold should be lessened (e.g., 3500 to 128 or 256, although it does not have to be power of 2). 3501 3502 default: 4096 3503 3504 CONFIG_MTD_UBI_BEB_LIMIT 3505 This option specifies the maximum bad physical eraseblocks UBI 3506 expects on the MTD device (per 1024 eraseblocks). If the 3507 underlying flash does not admit of bad eraseblocks (e.g. NOR 3508 flash), this value is ignored. 3509 3510 NAND datasheets often specify the minimum and maximum NVM 3511 (Number of Valid Blocks) for the flashes' endurance lifetime. 3512 The maximum expected bad eraseblocks per 1024 eraseblocks 3513 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3514 which gives 20 for most NANDs (MaxNVB is basically the total 3515 count of eraseblocks on the chip). 3516 3517 To put it differently, if this value is 20, UBI will try to 3518 reserve about 1.9% of physical eraseblocks for bad blocks 3519 handling. And that will be 1.9% of eraseblocks on the entire 3520 NAND chip, not just the MTD partition UBI attaches. This means 3521 that if you have, say, a NAND flash chip admits maximum 40 bad 3522 eraseblocks, and it is split on two MTD partitions of the same 3523 size, UBI will reserve 40 eraseblocks when attaching a 3524 partition. 3525 3526 default: 20 3527 3528 CONFIG_MTD_UBI_FASTMAP 3529 Fastmap is a mechanism which allows attaching an UBI device 3530 in nearly constant time. Instead of scanning the whole MTD device it 3531 only has to locate a checkpoint (called fastmap) on the device. 3532 The on-flash fastmap contains all information needed to attach 3533 the device. Using fastmap makes only sense on large devices where 3534 attaching by scanning takes long. UBI will not automatically install 3535 a fastmap on old images, but you can set the UBI parameter 3536 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3537 that fastmap-enabled images are still usable with UBI implementations 3538 without fastmap support. On typical flash devices the whole fastmap 3539 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3540 3541 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3542 Set this parameter to enable fastmap automatically on images 3543 without a fastmap. 3544 default: 0 3545 3546- UBIFS support 3547 CONFIG_CMD_UBIFS 3548 3549 Adds commands for interacting with UBI volumes formatted as 3550 UBIFS. UBIFS is read-only in u-boot. 3551 3552 Requires UBI support as well as CONFIG_LZO 3553 3554 CONFIG_UBIFS_SILENCE_MSG 3555 3556 Make the verbose messages from UBIFS stop printing. This leaves 3557 warnings and errors enabled. 3558 3559- SPL framework 3560 CONFIG_SPL 3561 Enable building of SPL globally. 3562 3563 CONFIG_SPL_LDSCRIPT 3564 LDSCRIPT for linking the SPL binary. 3565 3566 CONFIG_SPL_MAX_FOOTPRINT 3567 Maximum size in memory allocated to the SPL, BSS included. 3568 When defined, the linker checks that the actual memory 3569 used by SPL from _start to __bss_end does not exceed it. 3570 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3571 must not be both defined at the same time. 3572 3573 CONFIG_SPL_MAX_SIZE 3574 Maximum size of the SPL image (text, data, rodata, and 3575 linker lists sections), BSS excluded. 3576 When defined, the linker checks that the actual size does 3577 not exceed it. 3578 3579 CONFIG_SPL_TEXT_BASE 3580 TEXT_BASE for linking the SPL binary. 3581 3582 CONFIG_SPL_RELOC_TEXT_BASE 3583 Address to relocate to. If unspecified, this is equal to 3584 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3585 3586 CONFIG_SPL_BSS_START_ADDR 3587 Link address for the BSS within the SPL binary. 3588 3589 CONFIG_SPL_BSS_MAX_SIZE 3590 Maximum size in memory allocated to the SPL BSS. 3591 When defined, the linker checks that the actual memory used 3592 by SPL from __bss_start to __bss_end does not exceed it. 3593 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3594 must not be both defined at the same time. 3595 3596 CONFIG_SPL_STACK 3597 Adress of the start of the stack SPL will use 3598 3599 CONFIG_SPL_RELOC_STACK 3600 Adress of the start of the stack SPL will use after 3601 relocation. If unspecified, this is equal to 3602 CONFIG_SPL_STACK. 3603 3604 CONFIG_SYS_SPL_MALLOC_START 3605 Starting address of the malloc pool used in SPL. 3606 3607 CONFIG_SYS_SPL_MALLOC_SIZE 3608 The size of the malloc pool used in SPL. 3609 3610 CONFIG_SPL_FRAMEWORK 3611 Enable the SPL framework under common/. This framework 3612 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3613 NAND loading of the Linux Kernel. 3614 3615 CONFIG_SPL_OS_BOOT 3616 Enable booting directly to an OS from SPL. 3617 See also: doc/README.falcon 3618 3619 CONFIG_SPL_DISPLAY_PRINT 3620 For ARM, enable an optional function to print more information 3621 about the running system. 3622 3623 CONFIG_SPL_INIT_MINIMAL 3624 Arch init code should be built for a very small image 3625 3626 CONFIG_SPL_LIBCOMMON_SUPPORT 3627 Support for common/libcommon.o in SPL binary 3628 3629 CONFIG_SPL_LIBDISK_SUPPORT 3630 Support for disk/libdisk.o in SPL binary 3631 3632 CONFIG_SPL_I2C_SUPPORT 3633 Support for drivers/i2c/libi2c.o in SPL binary 3634 3635 CONFIG_SPL_GPIO_SUPPORT 3636 Support for drivers/gpio/libgpio.o in SPL binary 3637 3638 CONFIG_SPL_MMC_SUPPORT 3639 Support for drivers/mmc/libmmc.o in SPL binary 3640 3641 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3642 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3643 Address and partition on the MMC to load U-Boot from 3644 when the MMC is being used in raw mode. 3645 3646 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3647 Partition on the MMC to load U-Boot from when the MMC is being 3648 used in raw mode 3649 3650 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3651 Sector to load kernel uImage from when MMC is being 3652 used in raw mode (for Falcon mode) 3653 3654 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3655 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3656 Sector and number of sectors to load kernel argument 3657 parameters from when MMC is being used in raw mode 3658 (for falcon mode) 3659 3660 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3661 Partition on the MMC to load U-Boot from when the MMC is being 3662 used in fs mode 3663 3664 CONFIG_SPL_FAT_SUPPORT 3665 Support for fs/fat/libfat.o in SPL binary 3666 3667 CONFIG_SPL_EXT_SUPPORT 3668 Support for EXT filesystem in SPL binary 3669 3670 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3671 Filename to read to load U-Boot when reading from filesystem 3672 3673 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3674 Filename to read to load kernel uImage when reading 3675 from filesystem (for Falcon mode) 3676 3677 CONFIG_SPL_FS_LOAD_ARGS_NAME 3678 Filename to read to load kernel argument parameters 3679 when reading from filesystem (for Falcon mode) 3680 3681 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3682 Set this for NAND SPL on PPC mpc83xx targets, so that 3683 start.S waits for the rest of the SPL to load before 3684 continuing (the hardware starts execution after just 3685 loading the first page rather than the full 4K). 3686 3687 CONFIG_SPL_SKIP_RELOCATE 3688 Avoid SPL relocation 3689 3690 CONFIG_SPL_NAND_BASE 3691 Include nand_base.c in the SPL. Requires 3692 CONFIG_SPL_NAND_DRIVERS. 3693 3694 CONFIG_SPL_NAND_DRIVERS 3695 SPL uses normal NAND drivers, not minimal drivers. 3696 3697 CONFIG_SPL_NAND_ECC 3698 Include standard software ECC in the SPL 3699 3700 CONFIG_SPL_NAND_SIMPLE 3701 Support for NAND boot using simple NAND drivers that 3702 expose the cmd_ctrl() interface. 3703 3704 CONFIG_SPL_MTD_SUPPORT 3705 Support for the MTD subsystem within SPL. Useful for 3706 environment on NAND support within SPL. 3707 3708 CONFIG_SPL_NAND_RAW_ONLY 3709 Support to boot only raw u-boot.bin images. Use this only 3710 if you need to save space. 3711 3712 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3713 Set for the SPL on PPC mpc8xxx targets, support for 3714 drivers/ddr/fsl/libddr.o in SPL binary. 3715 3716 CONFIG_SPL_COMMON_INIT_DDR 3717 Set for common ddr init with serial presence detect in 3718 SPL binary. 3719 3720 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3721 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3722 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3723 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3724 CONFIG_SYS_NAND_ECCBYTES 3725 Defines the size and behavior of the NAND that SPL uses 3726 to read U-Boot 3727 3728 CONFIG_SPL_NAND_BOOT 3729 Add support NAND boot 3730 3731 CONFIG_SYS_NAND_U_BOOT_OFFS 3732 Location in NAND to read U-Boot from 3733 3734 CONFIG_SYS_NAND_U_BOOT_DST 3735 Location in memory to load U-Boot to 3736 3737 CONFIG_SYS_NAND_U_BOOT_SIZE 3738 Size of image to load 3739 3740 CONFIG_SYS_NAND_U_BOOT_START 3741 Entry point in loaded image to jump to 3742 3743 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3744 Define this if you need to first read the OOB and then the 3745 data. This is used, for example, on davinci platforms. 3746 3747 CONFIG_SPL_OMAP3_ID_NAND 3748 Support for an OMAP3-specific set of functions to return the 3749 ID and MFR of the first attached NAND chip, if present. 3750 3751 CONFIG_SPL_SERIAL_SUPPORT 3752 Support for drivers/serial/libserial.o in SPL binary 3753 3754 CONFIG_SPL_SPI_FLASH_SUPPORT 3755 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3756 3757 CONFIG_SPL_SPI_SUPPORT 3758 Support for drivers/spi/libspi.o in SPL binary 3759 3760 CONFIG_SPL_RAM_DEVICE 3761 Support for running image already present in ram, in SPL binary 3762 3763 CONFIG_SPL_LIBGENERIC_SUPPORT 3764 Support for lib/libgeneric.o in SPL binary 3765 3766 CONFIG_SPL_ENV_SUPPORT 3767 Support for the environment operating in SPL binary 3768 3769 CONFIG_SPL_NET_SUPPORT 3770 Support for the net/libnet.o in SPL binary. 3771 It conflicts with SPL env from storage medium specified by 3772 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3773 3774 CONFIG_SPL_PAD_TO 3775 Image offset to which the SPL should be padded before appending 3776 the SPL payload. By default, this is defined as 3777 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3778 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3779 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3780 3781 CONFIG_SPL_TARGET 3782 Final target image containing SPL and payload. Some SPLs 3783 use an arch-specific makefile fragment instead, for 3784 example if more than one image needs to be produced. 3785 3786 CONFIG_FIT_SPL_PRINT 3787 Printing information about a FIT image adds quite a bit of 3788 code to SPL. So this is normally disabled in SPL. Use this 3789 option to re-enable it. This will affect the output of the 3790 bootm command when booting a FIT image. 3791 3792- TPL framework 3793 CONFIG_TPL 3794 Enable building of TPL globally. 3795 3796 CONFIG_TPL_PAD_TO 3797 Image offset to which the TPL should be padded before appending 3798 the TPL payload. By default, this is defined as 3799 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3800 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3801 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3802 3803Modem Support: 3804-------------- 3805 3806[so far only for SMDK2400 boards] 3807 3808- Modem support enable: 3809 CONFIG_MODEM_SUPPORT 3810 3811- RTS/CTS Flow control enable: 3812 CONFIG_HWFLOW 3813 3814- Modem debug support: 3815 CONFIG_MODEM_SUPPORT_DEBUG 3816 3817 Enables debugging stuff (char screen[1024], dbg()) 3818 for modem support. Useful only with BDI2000. 3819 3820- Interrupt support (PPC): 3821 3822 There are common interrupt_init() and timer_interrupt() 3823 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3824 for CPU specific initialization. interrupt_init_cpu() 3825 should set decrementer_count to appropriate value. If 3826 CPU resets decrementer automatically after interrupt 3827 (ppc4xx) it should set decrementer_count to zero. 3828 timer_interrupt() calls timer_interrupt_cpu() for CPU 3829 specific handling. If board has watchdog / status_led 3830 / other_activity_monitor it works automatically from 3831 general timer_interrupt(). 3832 3833- General: 3834 3835 In the target system modem support is enabled when a 3836 specific key (key combination) is pressed during 3837 power-on. Otherwise U-Boot will boot normally 3838 (autoboot). The key_pressed() function is called from 3839 board_init(). Currently key_pressed() is a dummy 3840 function, returning 1 and thus enabling modem 3841 initialization. 3842 3843 If there are no modem init strings in the 3844 environment, U-Boot proceed to autoboot; the 3845 previous output (banner, info printfs) will be 3846 suppressed, though. 3847 3848 See also: doc/README.Modem 3849 3850Board initialization settings: 3851------------------------------ 3852 3853During Initialization u-boot calls a number of board specific functions 3854to allow the preparation of board specific prerequisites, e.g. pin setup 3855before drivers are initialized. To enable these callbacks the 3856following configuration macros have to be defined. Currently this is 3857architecture specific, so please check arch/your_architecture/lib/board.c 3858typically in board_init_f() and board_init_r(). 3859 3860- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3861- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3862- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3863- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3864 3865Configuration Settings: 3866----------------------- 3867 3868- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3869 Optionally it can be defined to support 64-bit memory commands. 3870 3871- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3872 undefine this when you're short of memory. 3873 3874- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3875 width of the commands listed in the 'help' command output. 3876 3877- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3878 prompt for user input. 3879 3880- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3881 3882- CONFIG_SYS_PBSIZE: Buffer size for Console output 3883 3884- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3885 3886- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3887 the application (usually a Linux kernel) when it is 3888 booted 3889 3890- CONFIG_SYS_BAUDRATE_TABLE: 3891 List of legal baudrate settings for this board. 3892 3893- CONFIG_SYS_CONSOLE_INFO_QUIET 3894 Suppress display of console information at boot. 3895 3896- CONFIG_SYS_CONSOLE_IS_IN_ENV 3897 If the board specific function 3898 extern int overwrite_console (void); 3899 returns 1, the stdin, stderr and stdout are switched to the 3900 serial port, else the settings in the environment are used. 3901 3902- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3903 Enable the call to overwrite_console(). 3904 3905- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3906 Enable overwrite of previous console environment settings. 3907 3908- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3909 Begin and End addresses of the area used by the 3910 simple memory test. 3911 3912- CONFIG_SYS_ALT_MEMTEST: 3913 Enable an alternate, more extensive memory test. 3914 3915- CONFIG_SYS_MEMTEST_SCRATCH: 3916 Scratch address used by the alternate memory test 3917 You only need to set this if address zero isn't writeable 3918 3919- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3920 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3921 this specified memory area will get subtracted from the top 3922 (end) of RAM and won't get "touched" at all by U-Boot. By 3923 fixing up gd->ram_size the Linux kernel should gets passed 3924 the now "corrected" memory size and won't touch it either. 3925 This should work for arch/ppc and arch/powerpc. Only Linux 3926 board ports in arch/powerpc with bootwrapper support that 3927 recalculate the memory size from the SDRAM controller setup 3928 will have to get fixed in Linux additionally. 3929 3930 This option can be used as a workaround for the 440EPx/GRx 3931 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3932 be touched. 3933 3934 WARNING: Please make sure that this value is a multiple of 3935 the Linux page size (normally 4k). If this is not the case, 3936 then the end address of the Linux memory will be located at a 3937 non page size aligned address and this could cause major 3938 problems. 3939 3940- CONFIG_SYS_LOADS_BAUD_CHANGE: 3941 Enable temporary baudrate change while serial download 3942 3943- CONFIG_SYS_SDRAM_BASE: 3944 Physical start address of SDRAM. _Must_ be 0 here. 3945 3946- CONFIG_SYS_MBIO_BASE: 3947 Physical start address of Motherboard I/O (if using a 3948 Cogent motherboard) 3949 3950- CONFIG_SYS_FLASH_BASE: 3951 Physical start address of Flash memory. 3952 3953- CONFIG_SYS_MONITOR_BASE: 3954 Physical start address of boot monitor code (set by 3955 make config files to be same as the text base address 3956 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3957 CONFIG_SYS_FLASH_BASE when booting from flash. 3958 3959- CONFIG_SYS_MONITOR_LEN: 3960 Size of memory reserved for monitor code, used to 3961 determine _at_compile_time_ (!) if the environment is 3962 embedded within the U-Boot image, or in a separate 3963 flash sector. 3964 3965- CONFIG_SYS_MALLOC_LEN: 3966 Size of DRAM reserved for malloc() use. 3967 3968- CONFIG_SYS_MALLOC_F_LEN 3969 Size of the malloc() pool for use before relocation. If 3970 this is defined, then a very simple malloc() implementation 3971 will become available before relocation. The address is just 3972 below the global data, and the stack is moved down to make 3973 space. 3974 3975 This feature allocates regions with increasing addresses 3976 within the region. calloc() is supported, but realloc() 3977 is not available. free() is supported but does nothing. 3978 The memory will be freed (or in fact just forgotten) when 3979 U-Boot relocates itself. 3980 3981 Pre-relocation malloc() is only supported on ARM and sandbox 3982 at present but is fairly easy to enable for other archs. 3983 3984- CONFIG_SYS_MALLOC_SIMPLE 3985 Provides a simple and small malloc() and calloc() for those 3986 boards which do not use the full malloc in SPL (which is 3987 enabled with CONFIG_SYS_SPL_MALLOC_START). 3988 3989- CONFIG_SYS_NONCACHED_MEMORY: 3990 Size of non-cached memory area. This area of memory will be 3991 typically located right below the malloc() area and mapped 3992 uncached in the MMU. This is useful for drivers that would 3993 otherwise require a lot of explicit cache maintenance. For 3994 some drivers it's also impossible to properly maintain the 3995 cache. For example if the regions that need to be flushed 3996 are not a multiple of the cache-line size, *and* padding 3997 cannot be allocated between the regions to align them (i.e. 3998 if the HW requires a contiguous array of regions, and the 3999 size of each region is not cache-aligned), then a flush of 4000 one region may result in overwriting data that hardware has 4001 written to another region in the same cache-line. This can 4002 happen for example in network drivers where descriptors for 4003 buffers are typically smaller than the CPU cache-line (e.g. 4004 16 bytes vs. 32 or 64 bytes). 4005 4006 Non-cached memory is only supported on 32-bit ARM at present. 4007 4008- CONFIG_SYS_BOOTM_LEN: 4009 Normally compressed uImages are limited to an 4010 uncompressed size of 8 MBytes. If this is not enough, 4011 you can define CONFIG_SYS_BOOTM_LEN in your board config file 4012 to adjust this setting to your needs. 4013 4014- CONFIG_SYS_BOOTMAPSZ: 4015 Maximum size of memory mapped by the startup code of 4016 the Linux kernel; all data that must be processed by 4017 the Linux kernel (bd_info, boot arguments, FDT blob if 4018 used) must be put below this limit, unless "bootm_low" 4019 environment variable is defined and non-zero. In such case 4020 all data for the Linux kernel must be between "bootm_low" 4021 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 4022 variable "bootm_mapsize" will override the value of 4023 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 4024 then the value in "bootm_size" will be used instead. 4025 4026- CONFIG_SYS_BOOT_RAMDISK_HIGH: 4027 Enable initrd_high functionality. If defined then the 4028 initrd_high feature is enabled and the bootm ramdisk subcommand 4029 is enabled. 4030 4031- CONFIG_SYS_BOOT_GET_CMDLINE: 4032 Enables allocating and saving kernel cmdline in space between 4033 "bootm_low" and "bootm_low" + BOOTMAPSZ. 4034 4035- CONFIG_SYS_BOOT_GET_KBD: 4036 Enables allocating and saving a kernel copy of the bd_info in 4037 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 4038 4039- CONFIG_SYS_MAX_FLASH_BANKS: 4040 Max number of Flash memory banks 4041 4042- CONFIG_SYS_MAX_FLASH_SECT: 4043 Max number of sectors on a Flash chip 4044 4045- CONFIG_SYS_FLASH_ERASE_TOUT: 4046 Timeout for Flash erase operations (in ms) 4047 4048- CONFIG_SYS_FLASH_WRITE_TOUT: 4049 Timeout for Flash write operations (in ms) 4050 4051- CONFIG_SYS_FLASH_LOCK_TOUT 4052 Timeout for Flash set sector lock bit operation (in ms) 4053 4054- CONFIG_SYS_FLASH_UNLOCK_TOUT 4055 Timeout for Flash clear lock bits operation (in ms) 4056 4057- CONFIG_SYS_FLASH_PROTECTION 4058 If defined, hardware flash sectors protection is used 4059 instead of U-Boot software protection. 4060 4061- CONFIG_SYS_DIRECT_FLASH_TFTP: 4062 4063 Enable TFTP transfers directly to flash memory; 4064 without this option such a download has to be 4065 performed in two steps: (1) download to RAM, and (2) 4066 copy from RAM to flash. 4067 4068 The two-step approach is usually more reliable, since 4069 you can check if the download worked before you erase 4070 the flash, but in some situations (when system RAM is 4071 too limited to allow for a temporary copy of the 4072 downloaded image) this option may be very useful. 4073 4074- CONFIG_SYS_FLASH_CFI: 4075 Define if the flash driver uses extra elements in the 4076 common flash structure for storing flash geometry. 4077 4078- CONFIG_FLASH_CFI_DRIVER 4079 This option also enables the building of the cfi_flash driver 4080 in the drivers directory 4081 4082- CONFIG_FLASH_CFI_MTD 4083 This option enables the building of the cfi_mtd driver 4084 in the drivers directory. The driver exports CFI flash 4085 to the MTD layer. 4086 4087- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 4088 Use buffered writes to flash. 4089 4090- CONFIG_FLASH_SPANSION_S29WS_N 4091 s29ws-n MirrorBit flash has non-standard addresses for buffered 4092 write commands. 4093 4094- CONFIG_SYS_FLASH_QUIET_TEST 4095 If this option is defined, the common CFI flash doesn't 4096 print it's warning upon not recognized FLASH banks. This 4097 is useful, if some of the configured banks are only 4098 optionally available. 4099 4100- CONFIG_FLASH_SHOW_PROGRESS 4101 If defined (must be an integer), print out countdown 4102 digits and dots. Recommended value: 45 (9..1) for 80 4103 column displays, 15 (3..1) for 40 column displays. 4104 4105- CONFIG_FLASH_VERIFY 4106 If defined, the content of the flash (destination) is compared 4107 against the source after the write operation. An error message 4108 will be printed when the contents are not identical. 4109 Please note that this option is useless in nearly all cases, 4110 since such flash programming errors usually are detected earlier 4111 while unprotecting/erasing/programming. Please only enable 4112 this option if you really know what you are doing. 4113 4114- CONFIG_SYS_RX_ETH_BUFFER: 4115 Defines the number of Ethernet receive buffers. On some 4116 Ethernet controllers it is recommended to set this value 4117 to 8 or even higher (EEPRO100 or 405 EMAC), since all 4118 buffers can be full shortly after enabling the interface 4119 on high Ethernet traffic. 4120 Defaults to 4 if not defined. 4121 4122- CONFIG_ENV_MAX_ENTRIES 4123 4124 Maximum number of entries in the hash table that is used 4125 internally to store the environment settings. The default 4126 setting is supposed to be generous and should work in most 4127 cases. This setting can be used to tune behaviour; see 4128 lib/hashtable.c for details. 4129 4130- CONFIG_ENV_FLAGS_LIST_DEFAULT 4131- CONFIG_ENV_FLAGS_LIST_STATIC 4132 Enable validation of the values given to environment variables when 4133 calling env set. Variables can be restricted to only decimal, 4134 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 4135 the variables can also be restricted to IP address or MAC address. 4136 4137 The format of the list is: 4138 type_attribute = [s|d|x|b|i|m] 4139 access_attribute = [a|r|o|c] 4140 attributes = type_attribute[access_attribute] 4141 entry = variable_name[:attributes] 4142 list = entry[,list] 4143 4144 The type attributes are: 4145 s - String (default) 4146 d - Decimal 4147 x - Hexadecimal 4148 b - Boolean ([1yYtT|0nNfF]) 4149 i - IP address 4150 m - MAC address 4151 4152 The access attributes are: 4153 a - Any (default) 4154 r - Read-only 4155 o - Write-once 4156 c - Change-default 4157 4158 - CONFIG_ENV_FLAGS_LIST_DEFAULT 4159 Define this to a list (string) to define the ".flags" 4160 environment variable in the default or embedded environment. 4161 4162 - CONFIG_ENV_FLAGS_LIST_STATIC 4163 Define this to a list (string) to define validation that 4164 should be done if an entry is not found in the ".flags" 4165 environment variable. To override a setting in the static 4166 list, simply add an entry for the same variable name to the 4167 ".flags" variable. 4168 4169- CONFIG_ENV_ACCESS_IGNORE_FORCE 4170 If defined, don't allow the -f switch to env set override variable 4171 access flags. 4172 4173- CONFIG_SYS_GENERIC_BOARD 4174 This selects the architecture-generic board system instead of the 4175 architecture-specific board files. It is intended to move boards 4176 to this new framework over time. Defining this will disable the 4177 arch/foo/lib/board.c file and use common/board_f.c and 4178 common/board_r.c instead. To use this option your architecture 4179 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in 4180 its config.mk file). If you find problems enabling this option on 4181 your board please report the problem and send patches! 4182 4183- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 4184 This is set by OMAP boards for the max time that reset should 4185 be asserted. See doc/README.omap-reset-time for details on how 4186 the value can be calculated on a given board. 4187 4188- CONFIG_USE_STDINT 4189 If stdint.h is available with your toolchain you can define this 4190 option to enable it. You can provide option 'USE_STDINT=1' when 4191 building U-Boot to enable this. 4192 4193The following definitions that deal with the placement and management 4194of environment data (variable area); in general, we support the 4195following configurations: 4196 4197- CONFIG_BUILD_ENVCRC: 4198 4199 Builds up envcrc with the target environment so that external utils 4200 may easily extract it and embed it in final U-Boot images. 4201 4202- CONFIG_ENV_IS_IN_FLASH: 4203 4204 Define this if the environment is in flash memory. 4205 4206 a) The environment occupies one whole flash sector, which is 4207 "embedded" in the text segment with the U-Boot code. This 4208 happens usually with "bottom boot sector" or "top boot 4209 sector" type flash chips, which have several smaller 4210 sectors at the start or the end. For instance, such a 4211 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 4212 such a case you would place the environment in one of the 4213 4 kB sectors - with U-Boot code before and after it. With 4214 "top boot sector" type flash chips, you would put the 4215 environment in one of the last sectors, leaving a gap 4216 between U-Boot and the environment. 4217 4218 - CONFIG_ENV_OFFSET: 4219 4220 Offset of environment data (variable area) to the 4221 beginning of flash memory; for instance, with bottom boot 4222 type flash chips the second sector can be used: the offset 4223 for this sector is given here. 4224 4225 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 4226 4227 - CONFIG_ENV_ADDR: 4228 4229 This is just another way to specify the start address of 4230 the flash sector containing the environment (instead of 4231 CONFIG_ENV_OFFSET). 4232 4233 - CONFIG_ENV_SECT_SIZE: 4234 4235 Size of the sector containing the environment. 4236 4237 4238 b) Sometimes flash chips have few, equal sized, BIG sectors. 4239 In such a case you don't want to spend a whole sector for 4240 the environment. 4241 4242 - CONFIG_ENV_SIZE: 4243 4244 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 4245 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 4246 of this flash sector for the environment. This saves 4247 memory for the RAM copy of the environment. 4248 4249 It may also save flash memory if you decide to use this 4250 when your environment is "embedded" within U-Boot code, 4251 since then the remainder of the flash sector could be used 4252 for U-Boot code. It should be pointed out that this is 4253 STRONGLY DISCOURAGED from a robustness point of view: 4254 updating the environment in flash makes it always 4255 necessary to erase the WHOLE sector. If something goes 4256 wrong before the contents has been restored from a copy in 4257 RAM, your target system will be dead. 4258 4259 - CONFIG_ENV_ADDR_REDUND 4260 CONFIG_ENV_SIZE_REDUND 4261 4262 These settings describe a second storage area used to hold 4263 a redundant copy of the environment data, so that there is 4264 a valid backup copy in case there is a power failure during 4265 a "saveenv" operation. 4266 4267BE CAREFUL! Any changes to the flash layout, and some changes to the 4268source code will make it necessary to adapt <board>/u-boot.lds* 4269accordingly! 4270 4271 4272- CONFIG_ENV_IS_IN_NVRAM: 4273 4274 Define this if you have some non-volatile memory device 4275 (NVRAM, battery buffered SRAM) which you want to use for the 4276 environment. 4277 4278 - CONFIG_ENV_ADDR: 4279 - CONFIG_ENV_SIZE: 4280 4281 These two #defines are used to determine the memory area you 4282 want to use for environment. It is assumed that this memory 4283 can just be read and written to, without any special 4284 provision. 4285 4286BE CAREFUL! The first access to the environment happens quite early 4287in U-Boot initialization (when we try to get the setting of for the 4288console baudrate). You *MUST* have mapped your NVRAM area then, or 4289U-Boot will hang. 4290 4291Please note that even with NVRAM we still use a copy of the 4292environment in RAM: we could work on NVRAM directly, but we want to 4293keep settings there always unmodified except somebody uses "saveenv" 4294to save the current settings. 4295 4296 4297- CONFIG_ENV_IS_IN_EEPROM: 4298 4299 Use this if you have an EEPROM or similar serial access 4300 device and a driver for it. 4301 4302 - CONFIG_ENV_OFFSET: 4303 - CONFIG_ENV_SIZE: 4304 4305 These two #defines specify the offset and size of the 4306 environment area within the total memory of your EEPROM. 4307 4308 - CONFIG_SYS_I2C_EEPROM_ADDR: 4309 If defined, specified the chip address of the EEPROM device. 4310 The default address is zero. 4311 4312 - CONFIG_SYS_I2C_EEPROM_BUS: 4313 If defined, specified the i2c bus of the EEPROM device. 4314 4315 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 4316 If defined, the number of bits used to address bytes in a 4317 single page in the EEPROM device. A 64 byte page, for example 4318 would require six bits. 4319 4320 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 4321 If defined, the number of milliseconds to delay between 4322 page writes. The default is zero milliseconds. 4323 4324 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 4325 The length in bytes of the EEPROM memory array address. Note 4326 that this is NOT the chip address length! 4327 4328 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 4329 EEPROM chips that implement "address overflow" are ones 4330 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 4331 address and the extra bits end up in the "chip address" bit 4332 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 4333 byte chips. 4334 4335 Note that we consider the length of the address field to 4336 still be one byte because the extra address bits are hidden 4337 in the chip address. 4338 4339 - CONFIG_SYS_EEPROM_SIZE: 4340 The size in bytes of the EEPROM device. 4341 4342 - CONFIG_ENV_EEPROM_IS_ON_I2C 4343 define this, if you have I2C and SPI activated, and your 4344 EEPROM, which holds the environment, is on the I2C bus. 4345 4346 - CONFIG_I2C_ENV_EEPROM_BUS 4347 if you have an Environment on an EEPROM reached over 4348 I2C muxes, you can define here, how to reach this 4349 EEPROM. For example: 4350 4351 #define CONFIG_I2C_ENV_EEPROM_BUS 1 4352 4353 EEPROM which holds the environment, is reached over 4354 a pca9547 i2c mux with address 0x70, channel 3. 4355 4356- CONFIG_ENV_IS_IN_DATAFLASH: 4357 4358 Define this if you have a DataFlash memory device which you 4359 want to use for the environment. 4360 4361 - CONFIG_ENV_OFFSET: 4362 - CONFIG_ENV_ADDR: 4363 - CONFIG_ENV_SIZE: 4364 4365 These three #defines specify the offset and size of the 4366 environment area within the total memory of your DataFlash placed 4367 at the specified address. 4368 4369- CONFIG_ENV_IS_IN_SPI_FLASH: 4370 4371 Define this if you have a SPI Flash memory device which you 4372 want to use for the environment. 4373 4374 - CONFIG_ENV_OFFSET: 4375 - CONFIG_ENV_SIZE: 4376 4377 These two #defines specify the offset and size of the 4378 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 4379 aligned to an erase sector boundary. 4380 4381 - CONFIG_ENV_SECT_SIZE: 4382 4383 Define the SPI flash's sector size. 4384 4385 - CONFIG_ENV_OFFSET_REDUND (optional): 4386 4387 This setting describes a second storage area of CONFIG_ENV_SIZE 4388 size used to hold a redundant copy of the environment data, so 4389 that there is a valid backup copy in case there is a power failure 4390 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4391 aligned to an erase sector boundary. 4392 4393 - CONFIG_ENV_SPI_BUS (optional): 4394 - CONFIG_ENV_SPI_CS (optional): 4395 4396 Define the SPI bus and chip select. If not defined they will be 0. 4397 4398 - CONFIG_ENV_SPI_MAX_HZ (optional): 4399 4400 Define the SPI max work clock. If not defined then use 1MHz. 4401 4402 - CONFIG_ENV_SPI_MODE (optional): 4403 4404 Define the SPI work mode. If not defined then use SPI_MODE_3. 4405 4406- CONFIG_ENV_IS_IN_REMOTE: 4407 4408 Define this if you have a remote memory space which you 4409 want to use for the local device's environment. 4410 4411 - CONFIG_ENV_ADDR: 4412 - CONFIG_ENV_SIZE: 4413 4414 These two #defines specify the address and size of the 4415 environment area within the remote memory space. The 4416 local device can get the environment from remote memory 4417 space by SRIO or PCIE links. 4418 4419BE CAREFUL! For some special cases, the local device can not use 4420"saveenv" command. For example, the local device will get the 4421environment stored in a remote NOR flash by SRIO or PCIE link, 4422but it can not erase, write this NOR flash by SRIO or PCIE interface. 4423 4424- CONFIG_ENV_IS_IN_NAND: 4425 4426 Define this if you have a NAND device which you want to use 4427 for the environment. 4428 4429 - CONFIG_ENV_OFFSET: 4430 - CONFIG_ENV_SIZE: 4431 4432 These two #defines specify the offset and size of the environment 4433 area within the first NAND device. CONFIG_ENV_OFFSET must be 4434 aligned to an erase block boundary. 4435 4436 - CONFIG_ENV_OFFSET_REDUND (optional): 4437 4438 This setting describes a second storage area of CONFIG_ENV_SIZE 4439 size used to hold a redundant copy of the environment data, so 4440 that there is a valid backup copy in case there is a power failure 4441 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4442 aligned to an erase block boundary. 4443 4444 - CONFIG_ENV_RANGE (optional): 4445 4446 Specifies the length of the region in which the environment 4447 can be written. This should be a multiple of the NAND device's 4448 block size. Specifying a range with more erase blocks than 4449 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4450 the range to be avoided. 4451 4452 - CONFIG_ENV_OFFSET_OOB (optional): 4453 4454 Enables support for dynamically retrieving the offset of the 4455 environment from block zero's out-of-band data. The 4456 "nand env.oob" command can be used to record this offset. 4457 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4458 using CONFIG_ENV_OFFSET_OOB. 4459 4460- CONFIG_NAND_ENV_DST 4461 4462 Defines address in RAM to which the nand_spl code should copy the 4463 environment. If redundant environment is used, it will be copied to 4464 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4465 4466- CONFIG_ENV_IS_IN_UBI: 4467 4468 Define this if you have an UBI volume that you want to use for the 4469 environment. This has the benefit of wear-leveling the environment 4470 accesses, which is important on NAND. 4471 4472 - CONFIG_ENV_UBI_PART: 4473 4474 Define this to a string that is the mtd partition containing the UBI. 4475 4476 - CONFIG_ENV_UBI_VOLUME: 4477 4478 Define this to the name of the volume that you want to store the 4479 environment in. 4480 4481 - CONFIG_ENV_UBI_VOLUME_REDUND: 4482 4483 Define this to the name of another volume to store a second copy of 4484 the environment in. This will enable redundant environments in UBI. 4485 It is assumed that both volumes are in the same MTD partition. 4486 4487 - CONFIG_UBI_SILENCE_MSG 4488 - CONFIG_UBIFS_SILENCE_MSG 4489 4490 You will probably want to define these to avoid a really noisy system 4491 when storing the env in UBI. 4492 4493- CONFIG_ENV_IS_IN_FAT: 4494 Define this if you want to use the FAT file system for the environment. 4495 4496 - FAT_ENV_INTERFACE: 4497 4498 Define this to a string that is the name of the block device. 4499 4500 - FAT_ENV_DEV_AND_PART: 4501 4502 Define this to a string to specify the partition of the device. It can 4503 be as following: 4504 4505 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 4506 - "D:P": device D partition P. Error occurs if device D has no 4507 partition table. 4508 - "D:0": device D. 4509 - "D" or "D:": device D partition 1 if device D has partition 4510 table, or the whole device D if has no partition 4511 table. 4512 - "D:auto": first partition in device D with bootable flag set. 4513 If none, first valid partition in device D. If no 4514 partition table then means device D. 4515 4516 - FAT_ENV_FILE: 4517 4518 It's a string of the FAT file name. This file use to store the 4519 environment. 4520 4521 - CONFIG_FAT_WRITE: 4522 This should be defined. Otherwise it cannot save the environment file. 4523 4524- CONFIG_ENV_IS_IN_MMC: 4525 4526 Define this if you have an MMC device which you want to use for the 4527 environment. 4528 4529 - CONFIG_SYS_MMC_ENV_DEV: 4530 4531 Specifies which MMC device the environment is stored in. 4532 4533 - CONFIG_SYS_MMC_ENV_PART (optional): 4534 4535 Specifies which MMC partition the environment is stored in. If not 4536 set, defaults to partition 0, the user area. Common values might be 4537 1 (first MMC boot partition), 2 (second MMC boot partition). 4538 4539 - CONFIG_ENV_OFFSET: 4540 - CONFIG_ENV_SIZE: 4541 4542 These two #defines specify the offset and size of the environment 4543 area within the specified MMC device. 4544 4545 If offset is positive (the usual case), it is treated as relative to 4546 the start of the MMC partition. If offset is negative, it is treated 4547 as relative to the end of the MMC partition. This can be useful if 4548 your board may be fitted with different MMC devices, which have 4549 different sizes for the MMC partitions, and you always want the 4550 environment placed at the very end of the partition, to leave the 4551 maximum possible space before it, to store other data. 4552 4553 These two values are in units of bytes, but must be aligned to an 4554 MMC sector boundary. 4555 4556 - CONFIG_ENV_OFFSET_REDUND (optional): 4557 4558 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4559 hold a redundant copy of the environment data. This provides a 4560 valid backup copy in case the other copy is corrupted, e.g. due 4561 to a power failure during a "saveenv" operation. 4562 4563 This value may also be positive or negative; this is handled in the 4564 same way as CONFIG_ENV_OFFSET. 4565 4566 This value is also in units of bytes, but must also be aligned to 4567 an MMC sector boundary. 4568 4569 - CONFIG_ENV_SIZE_REDUND (optional): 4570 4571 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4572 set. If this value is set, it must be set to the same value as 4573 CONFIG_ENV_SIZE. 4574 4575- CONFIG_SYS_SPI_INIT_OFFSET 4576 4577 Defines offset to the initial SPI buffer area in DPRAM. The 4578 area is used at an early stage (ROM part) if the environment 4579 is configured to reside in the SPI EEPROM: We need a 520 byte 4580 scratch DPRAM area. It is used between the two initialization 4581 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4582 to be a good choice since it makes it far enough from the 4583 start of the data area as well as from the stack pointer. 4584 4585Please note that the environment is read-only until the monitor 4586has been relocated to RAM and a RAM copy of the environment has been 4587created; also, when using EEPROM you will have to use getenv_f() 4588until then to read environment variables. 4589 4590The environment is protected by a CRC32 checksum. Before the monitor 4591is relocated into RAM, as a result of a bad CRC you will be working 4592with the compiled-in default environment - *silently*!!! [This is 4593necessary, because the first environment variable we need is the 4594"baudrate" setting for the console - if we have a bad CRC, we don't 4595have any device yet where we could complain.] 4596 4597Note: once the monitor has been relocated, then it will complain if 4598the default environment is used; a new CRC is computed as soon as you 4599use the "saveenv" command to store a valid environment. 4600 4601- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4602 Echo the inverted Ethernet link state to the fault LED. 4603 4604 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4605 also needs to be defined. 4606 4607- CONFIG_SYS_FAULT_MII_ADDR: 4608 MII address of the PHY to check for the Ethernet link state. 4609 4610- CONFIG_NS16550_MIN_FUNCTIONS: 4611 Define this if you desire to only have use of the NS16550_init 4612 and NS16550_putc functions for the serial driver located at 4613 drivers/serial/ns16550.c. This option is useful for saving 4614 space for already greatly restricted images, including but not 4615 limited to NAND_SPL configurations. 4616 4617- CONFIG_DISPLAY_BOARDINFO 4618 Display information about the board that U-Boot is running on 4619 when U-Boot starts up. The board function checkboard() is called 4620 to do this. 4621 4622- CONFIG_DISPLAY_BOARDINFO_LATE 4623 Similar to the previous option, but display this information 4624 later, once stdio is running and output goes to the LCD, if 4625 present. 4626 4627- CONFIG_BOARD_SIZE_LIMIT: 4628 Maximum size of the U-Boot image. When defined, the 4629 build system checks that the actual size does not 4630 exceed it. 4631 4632Low Level (hardware related) configuration options: 4633--------------------------------------------------- 4634 4635- CONFIG_SYS_CACHELINE_SIZE: 4636 Cache Line Size of the CPU. 4637 4638- CONFIG_SYS_DEFAULT_IMMR: 4639 Default address of the IMMR after system reset. 4640 4641 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4642 and RPXsuper) to be able to adjust the position of 4643 the IMMR register after a reset. 4644 4645- CONFIG_SYS_CCSRBAR_DEFAULT: 4646 Default (power-on reset) physical address of CCSR on Freescale 4647 PowerPC SOCs. 4648 4649- CONFIG_SYS_CCSRBAR: 4650 Virtual address of CCSR. On a 32-bit build, this is typically 4651 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4652 4653 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4654 for cross-platform code that uses that macro instead. 4655 4656- CONFIG_SYS_CCSRBAR_PHYS: 4657 Physical address of CCSR. CCSR can be relocated to a new 4658 physical address, if desired. In this case, this macro should 4659 be set to that address. Otherwise, it should be set to the 4660 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4661 is typically relocated on 36-bit builds. It is recommended 4662 that this macro be defined via the _HIGH and _LOW macros: 4663 4664 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4665 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4666 4667- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4668 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4669 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4670 used in assembly code, so it must not contain typecasts or 4671 integer size suffixes (e.g. "ULL"). 4672 4673- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4674 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4675 used in assembly code, so it must not contain typecasts or 4676 integer size suffixes (e.g. "ULL"). 4677 4678- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4679 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4680 forced to a value that ensures that CCSR is not relocated. 4681 4682- Floppy Disk Support: 4683 CONFIG_SYS_FDC_DRIVE_NUMBER 4684 4685 the default drive number (default value 0) 4686 4687 CONFIG_SYS_ISA_IO_STRIDE 4688 4689 defines the spacing between FDC chipset registers 4690 (default value 1) 4691 4692 CONFIG_SYS_ISA_IO_OFFSET 4693 4694 defines the offset of register from address. It 4695 depends on which part of the data bus is connected to 4696 the FDC chipset. (default value 0) 4697 4698 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4699 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4700 default value. 4701 4702 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4703 fdc_hw_init() is called at the beginning of the FDC 4704 setup. fdc_hw_init() must be provided by the board 4705 source code. It is used to make hardware-dependent 4706 initializations. 4707 4708- CONFIG_IDE_AHB: 4709 Most IDE controllers were designed to be connected with PCI 4710 interface. Only few of them were designed for AHB interface. 4711 When software is doing ATA command and data transfer to 4712 IDE devices through IDE-AHB controller, some additional 4713 registers accessing to these kind of IDE-AHB controller 4714 is required. 4715 4716- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4717 DO NOT CHANGE unless you know exactly what you're 4718 doing! (11-4) [MPC8xx/82xx systems only] 4719 4720- CONFIG_SYS_INIT_RAM_ADDR: 4721 4722 Start address of memory area that can be used for 4723 initial data and stack; please note that this must be 4724 writable memory that is working WITHOUT special 4725 initialization, i. e. you CANNOT use normal RAM which 4726 will become available only after programming the 4727 memory controller and running certain initialization 4728 sequences. 4729 4730 U-Boot uses the following memory types: 4731 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4732 - MPC824X: data cache 4733 - PPC4xx: data cache 4734 4735- CONFIG_SYS_GBL_DATA_OFFSET: 4736 4737 Offset of the initial data structure in the memory 4738 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4739 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4740 data is located at the end of the available space 4741 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4742 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4743 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4744 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4745 4746 Note: 4747 On the MPC824X (or other systems that use the data 4748 cache for initial memory) the address chosen for 4749 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4750 point to an otherwise UNUSED address space between 4751 the top of RAM and the start of the PCI space. 4752 4753- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4754 4755- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4756 4757- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4758 4759- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4760 4761- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4762 4763- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4764 4765- CONFIG_SYS_OR_TIMING_SDRAM: 4766 SDRAM timing 4767 4768- CONFIG_SYS_MAMR_PTA: 4769 periodic timer for refresh 4770 4771- CONFIG_SYS_DER: Debug Event Register (37-47) 4772 4773- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4774 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4775 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4776 CONFIG_SYS_BR1_PRELIM: 4777 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4778 4779- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4780 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4781 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4782 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4783 4784- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4785 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4786 Machine Mode Register and Memory Periodic Timer 4787 Prescaler definitions (SDRAM timing) 4788 4789- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4790 enable I2C microcode relocation patch (MPC8xx); 4791 define relocation offset in DPRAM [DSP2] 4792 4793- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4794 enable SMC microcode relocation patch (MPC8xx); 4795 define relocation offset in DPRAM [SMC1] 4796 4797- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4798 enable SPI microcode relocation patch (MPC8xx); 4799 define relocation offset in DPRAM [SCC4] 4800 4801- CONFIG_SYS_USE_OSCCLK: 4802 Use OSCM clock mode on MBX8xx board. Be careful, 4803 wrong setting might damage your board. Read 4804 doc/README.MBX before setting this variable! 4805 4806- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4807 Offset of the bootmode word in DPRAM used by post 4808 (Power On Self Tests). This definition overrides 4809 #define'd default value in commproc.h resp. 4810 cpm_8260.h. 4811 4812- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4813 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4814 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4815 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4816 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4817 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4818 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4819 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4820 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4821 4822- CONFIG_PCI_DISABLE_PCIE: 4823 Disable PCI-Express on systems where it is supported but not 4824 required. 4825 4826- CONFIG_PCI_ENUM_ONLY 4827 Only scan through and get the devices on the buses. 4828 Don't do any setup work, presumably because someone or 4829 something has already done it, and we don't need to do it 4830 a second time. Useful for platforms that are pre-booted 4831 by coreboot or similar. 4832 4833- CONFIG_PCI_INDIRECT_BRIDGE: 4834 Enable support for indirect PCI bridges. 4835 4836- CONFIG_SYS_SRIO: 4837 Chip has SRIO or not 4838 4839- CONFIG_SRIO1: 4840 Board has SRIO 1 port available 4841 4842- CONFIG_SRIO2: 4843 Board has SRIO 2 port available 4844 4845- CONFIG_SRIO_PCIE_BOOT_MASTER 4846 Board can support master function for Boot from SRIO and PCIE 4847 4848- CONFIG_SYS_SRIOn_MEM_VIRT: 4849 Virtual Address of SRIO port 'n' memory region 4850 4851- CONFIG_SYS_SRIOn_MEM_PHYS: 4852 Physical Address of SRIO port 'n' memory region 4853 4854- CONFIG_SYS_SRIOn_MEM_SIZE: 4855 Size of SRIO port 'n' memory region 4856 4857- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4858 Defined to tell the NAND controller that the NAND chip is using 4859 a 16 bit bus. 4860 Not all NAND drivers use this symbol. 4861 Example of drivers that use it: 4862 - drivers/mtd/nand/ndfc.c 4863 - drivers/mtd/nand/mxc_nand.c 4864 4865- CONFIG_SYS_NDFC_EBC0_CFG 4866 Sets the EBC0_CFG register for the NDFC. If not defined 4867 a default value will be used. 4868 4869- CONFIG_SPD_EEPROM 4870 Get DDR timing information from an I2C EEPROM. Common 4871 with pluggable memory modules such as SODIMMs 4872 4873 SPD_EEPROM_ADDRESS 4874 I2C address of the SPD EEPROM 4875 4876- CONFIG_SYS_SPD_BUS_NUM 4877 If SPD EEPROM is on an I2C bus other than the first 4878 one, specify here. Note that the value must resolve 4879 to something your driver can deal with. 4880 4881- CONFIG_SYS_DDR_RAW_TIMING 4882 Get DDR timing information from other than SPD. Common with 4883 soldered DDR chips onboard without SPD. DDR raw timing 4884 parameters are extracted from datasheet and hard-coded into 4885 header files or board specific files. 4886 4887- CONFIG_FSL_DDR_INTERACTIVE 4888 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4889 4890- CONFIG_FSL_DDR_SYNC_REFRESH 4891 Enable sync of refresh for multiple controllers. 4892 4893- CONFIG_SYS_83XX_DDR_USES_CS0 4894 Only for 83xx systems. If specified, then DDR should 4895 be configured using CS0 and CS1 instead of CS2 and CS3. 4896 4897- CONFIG_ETHER_ON_FEC[12] 4898 Define to enable FEC[12] on a 8xx series processor. 4899 4900- CONFIG_FEC[12]_PHY 4901 Define to the hardcoded PHY address which corresponds 4902 to the given FEC; i. e. 4903 #define CONFIG_FEC1_PHY 4 4904 means that the PHY with address 4 is connected to FEC1 4905 4906 When set to -1, means to probe for first available. 4907 4908- CONFIG_FEC[12]_PHY_NORXERR 4909 The PHY does not have a RXERR line (RMII only). 4910 (so program the FEC to ignore it). 4911 4912- CONFIG_RMII 4913 Enable RMII mode for all FECs. 4914 Note that this is a global option, we can't 4915 have one FEC in standard MII mode and another in RMII mode. 4916 4917- CONFIG_CRC32_VERIFY 4918 Add a verify option to the crc32 command. 4919 The syntax is: 4920 4921 => crc32 -v <address> <count> <crc32> 4922 4923 Where address/count indicate a memory area 4924 and crc32 is the correct crc32 which the 4925 area should have. 4926 4927- CONFIG_LOOPW 4928 Add the "loopw" memory command. This only takes effect if 4929 the memory commands are activated globally (CONFIG_CMD_MEM). 4930 4931- CONFIG_MX_CYCLIC 4932 Add the "mdc" and "mwc" memory commands. These are cyclic 4933 "md/mw" commands. 4934 Examples: 4935 4936 => mdc.b 10 4 500 4937 This command will print 4 bytes (10,11,12,13) each 500 ms. 4938 4939 => mwc.l 100 12345678 10 4940 This command will write 12345678 to address 100 all 10 ms. 4941 4942 This only takes effect if the memory commands are activated 4943 globally (CONFIG_CMD_MEM). 4944 4945- CONFIG_SKIP_LOWLEVEL_INIT 4946 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4947 low level initializations (like setting up the memory 4948 controller) are omitted and/or U-Boot does not 4949 relocate itself into RAM. 4950 4951 Normally this variable MUST NOT be defined. The only 4952 exception is when U-Boot is loaded (to RAM) by some 4953 other boot loader or by a debugger which performs 4954 these initializations itself. 4955 4956- CONFIG_SPL_BUILD 4957 Modifies the behaviour of start.S when compiling a loader 4958 that is executed before the actual U-Boot. E.g. when 4959 compiling a NAND SPL. 4960 4961- CONFIG_TPL_BUILD 4962 Modifies the behaviour of start.S when compiling a loader 4963 that is executed after the SPL and before the actual U-Boot. 4964 It is loaded by the SPL. 4965 4966- CONFIG_SYS_MPC85XX_NO_RESETVEC 4967 Only for 85xx systems. If this variable is specified, the section 4968 .resetvec is not kept and the section .bootpg is placed in the 4969 previous 4k of the .text section. 4970 4971- CONFIG_ARCH_MAP_SYSMEM 4972 Generally U-Boot (and in particular the md command) uses 4973 effective address. It is therefore not necessary to regard 4974 U-Boot address as virtual addresses that need to be translated 4975 to physical addresses. However, sandbox requires this, since 4976 it maintains its own little RAM buffer which contains all 4977 addressable memory. This option causes some memory accesses 4978 to be mapped through map_sysmem() / unmap_sysmem(). 4979 4980- CONFIG_USE_ARCH_MEMCPY 4981 CONFIG_USE_ARCH_MEMSET 4982 If these options are used a optimized version of memcpy/memset will 4983 be used if available. These functions may be faster under some 4984 conditions but may increase the binary size. 4985 4986- CONFIG_X86_RESET_VECTOR 4987 If defined, the x86 reset vector code is included. This is not 4988 needed when U-Boot is running from Coreboot. 4989 4990- CONFIG_SYS_MPUCLK 4991 Defines the MPU clock speed (in MHz). 4992 4993 NOTE : currently only supported on AM335x platforms. 4994 4995- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4996 Enables the RTC32K OSC on AM33xx based plattforms 4997 4998- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4999 Option to disable subpage write in NAND driver 5000 driver that uses this: 5001 drivers/mtd/nand/davinci_nand.c 5002 5003Freescale QE/FMAN Firmware Support: 5004----------------------------------- 5005 5006The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 5007loading of "firmware", which is encoded in the QE firmware binary format. 5008This firmware often needs to be loaded during U-Boot booting, so macros 5009are used to identify the storage device (NOR flash, SPI, etc) and the address 5010within that device. 5011 5012- CONFIG_SYS_FMAN_FW_ADDR 5013 The address in the storage device where the FMAN microcode is located. The 5014 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 5015 is also specified. 5016 5017- CONFIG_SYS_QE_FW_ADDR 5018 The address in the storage device where the QE 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_FMAN_FW_LENGTH 5023 The maximum possible size of the firmware. The firmware binary format 5024 has a field that specifies the actual size of the firmware, but it 5025 might not be possible to read any part of the firmware unless some 5026 local storage is allocated to hold the entire firmware first. 5027 5028- CONFIG_SYS_QE_FMAN_FW_IN_NOR 5029 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 5030 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 5031 virtual address in NOR flash. 5032 5033- CONFIG_SYS_QE_FMAN_FW_IN_NAND 5034 Specifies that QE/FMAN firmware is located in NAND flash. 5035 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 5036 5037- CONFIG_SYS_QE_FMAN_FW_IN_MMC 5038 Specifies that QE/FMAN firmware is located on the primary SD/MMC 5039 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5040 5041- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 5042 Specifies that QE/FMAN firmware is located on the primary SPI 5043 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 5044 5045- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 5046 Specifies that QE/FMAN firmware is located in the remote (master) 5047 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 5048 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 5049 window->master inbound window->master LAW->the ucode address in 5050 master's memory space. 5051 5052Freescale Layerscape Management Complex Firmware Support: 5053--------------------------------------------------------- 5054The Freescale Layerscape Management Complex (MC) supports the loading of 5055"firmware". 5056This firmware often needs to be loaded during U-Boot booting, so macros 5057are used to identify the storage device (NOR flash, SPI, etc) and the address 5058within that device. 5059 5060- CONFIG_FSL_MC_ENET 5061 Enable the MC driver for Layerscape SoCs. 5062 5063- CONFIG_SYS_LS_MC_FW_ADDR 5064 The address in the storage device where the firmware is located. The 5065 meaning of this address depends on which CONFIG_SYS_LS_MC_FW_IN_xxx macro 5066 is also specified. 5067 5068- CONFIG_SYS_LS_MC_FW_LENGTH 5069 The maximum possible size of the firmware. The firmware binary format 5070 has a field that specifies the actual size of the firmware, but it 5071 might not be possible to read any part of the firmware unless some 5072 local storage is allocated to hold the entire firmware first. 5073 5074- CONFIG_SYS_LS_MC_FW_IN_NOR 5075 Specifies that MC firmware is located in NOR flash, mapped as 5076 normal addressable memory via the LBC. CONFIG_SYS_LS_MC_FW_ADDR is the 5077 virtual address in NOR flash. 5078 5079Building the Software: 5080====================== 5081 5082Building U-Boot has been tested in several native build environments 5083and in many different cross environments. Of course we cannot support 5084all possibly existing versions of cross development tools in all 5085(potentially obsolete) versions. In case of tool chain problems we 5086recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 5087which is extensively used to build and test U-Boot. 5088 5089If you are not using a native environment, it is assumed that you 5090have GNU cross compiling tools available in your path. In this case, 5091you must set the environment variable CROSS_COMPILE in your shell. 5092Note that no changes to the Makefile or any other source files are 5093necessary. For example using the ELDK on a 4xx CPU, please enter: 5094 5095 $ CROSS_COMPILE=ppc_4xx- 5096 $ export CROSS_COMPILE 5097 5098Note: If you wish to generate Windows versions of the utilities in 5099 the tools directory you can use the MinGW toolchain 5100 (http://www.mingw.org). Set your HOST tools to the MinGW 5101 toolchain and execute 'make tools'. For example: 5102 5103 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 5104 5105 Binaries such as tools/mkimage.exe will be created which can 5106 be executed on computers running Windows. 5107 5108U-Boot is intended to be simple to build. After installing the 5109sources you must configure U-Boot for one specific board type. This 5110is done by typing: 5111 5112 make NAME_defconfig 5113 5114where "NAME_defconfig" is the name of one of the existing configu- 5115rations; see boards.cfg for supported names. 5116 5117Note: for some board special configuration names may exist; check if 5118 additional information is available from the board vendor; for 5119 instance, the TQM823L systems are available without (standard) 5120 or with LCD support. You can select such additional "features" 5121 when choosing the configuration, i. e. 5122 5123 make TQM823L_defconfig 5124 - will configure for a plain TQM823L, i. e. no LCD support 5125 5126 make TQM823L_LCD_defconfig 5127 - will configure for a TQM823L with U-Boot console on LCD 5128 5129 etc. 5130 5131 5132Finally, type "make all", and you should get some working U-Boot 5133images ready for download to / installation on your system: 5134 5135- "u-boot.bin" is a raw binary image 5136- "u-boot" is an image in ELF binary format 5137- "u-boot.srec" is in Motorola S-Record format 5138 5139By default the build is performed locally and the objects are saved 5140in the source directory. One of the two methods can be used to change 5141this behavior and build U-Boot to some external directory: 5142 51431. Add O= to the make command line invocations: 5144 5145 make O=/tmp/build distclean 5146 make O=/tmp/build NAME_defconfig 5147 make O=/tmp/build all 5148 51492. Set environment variable KBUILD_OUTPUT to point to the desired location: 5150 5151 export KBUILD_OUTPUT=/tmp/build 5152 make distclean 5153 make NAME_defconfig 5154 make all 5155 5156Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 5157variable. 5158 5159 5160Please be aware that the Makefiles assume you are using GNU make, so 5161for instance on NetBSD you might need to use "gmake" instead of 5162native "make". 5163 5164 5165If the system board that you have is not listed, then you will need 5166to port U-Boot to your hardware platform. To do this, follow these 5167steps: 5168 51691. Add a new configuration option for your board to the toplevel 5170 "boards.cfg" file, using the existing entries as examples. 5171 Follow the instructions there to keep the boards in order. 51722. Create a new directory to hold your board specific code. Add any 5173 files you need. In your board directory, you will need at least 5174 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 51753. Create a new configuration file "include/configs/<board>.h" for 5176 your board 51773. If you're porting U-Boot to a new CPU, then also create a new 5178 directory to hold your CPU specific code. Add any files you need. 51794. Run "make <board>_defconfig" with your new name. 51805. Type "make", and you should get a working "u-boot.srec" file 5181 to be installed on your target system. 51826. Debug and solve any problems that might arise. 5183 [Of course, this last step is much harder than it sounds.] 5184 5185 5186Testing of U-Boot Modifications, Ports to New Hardware, etc.: 5187============================================================== 5188 5189If you have modified U-Boot sources (for instance added a new board 5190or support for new devices, a new CPU, etc.) you are expected to 5191provide feedback to the other developers. The feedback normally takes 5192the form of a "patch", i. e. a context diff against a certain (latest 5193official or latest in the git repository) version of U-Boot sources. 5194 5195But before you submit such a patch, please verify that your modifi- 5196cation did not break existing code. At least make sure that *ALL* of 5197the supported boards compile WITHOUT ANY compiler warnings. To do so, 5198just run the "MAKEALL" script, which will configure and build U-Boot 5199for ALL supported system. Be warned, this will take a while. You can 5200select which (cross) compiler to use by passing a `CROSS_COMPILE' 5201environment variable to the script, i. e. to use the ELDK cross tools 5202you can type 5203 5204 CROSS_COMPILE=ppc_8xx- MAKEALL 5205 5206or to build on a native PowerPC system you can type 5207 5208 CROSS_COMPILE=' ' MAKEALL 5209 5210When using the MAKEALL script, the default behaviour is to build 5211U-Boot in the source directory. This location can be changed by 5212setting the BUILD_DIR environment variable. Also, for each target 5213built, the MAKEALL script saves two log files (<target>.ERR and 5214<target>.MAKEALL) in the <source dir>/LOG directory. This default 5215location can be changed by setting the MAKEALL_LOGDIR environment 5216variable. For example: 5217 5218 export BUILD_DIR=/tmp/build 5219 export MAKEALL_LOGDIR=/tmp/log 5220 CROSS_COMPILE=ppc_8xx- MAKEALL 5221 5222With the above settings build objects are saved in the /tmp/build, 5223log files are saved in the /tmp/log and the source tree remains clean 5224during the whole build process. 5225 5226 5227See also "U-Boot Porting Guide" below. 5228 5229 5230Monitor Commands - Overview: 5231============================ 5232 5233go - start application at address 'addr' 5234run - run commands in an environment variable 5235bootm - boot application image from memory 5236bootp - boot image via network using BootP/TFTP protocol 5237bootz - boot zImage from memory 5238tftpboot- boot image via network using TFTP protocol 5239 and env variables "ipaddr" and "serverip" 5240 (and eventually "gatewayip") 5241tftpput - upload a file via network using TFTP protocol 5242rarpboot- boot image via network using RARP/TFTP protocol 5243diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 5244loads - load S-Record file over serial line 5245loadb - load binary file over serial line (kermit mode) 5246md - memory display 5247mm - memory modify (auto-incrementing) 5248nm - memory modify (constant address) 5249mw - memory write (fill) 5250cp - memory copy 5251cmp - memory compare 5252crc32 - checksum calculation 5253i2c - I2C sub-system 5254sspi - SPI utility commands 5255base - print or set address offset 5256printenv- print environment variables 5257setenv - set environment variables 5258saveenv - save environment variables to persistent storage 5259protect - enable or disable FLASH write protection 5260erase - erase FLASH memory 5261flinfo - print FLASH memory information 5262nand - NAND memory operations (see doc/README.nand) 5263bdinfo - print Board Info structure 5264iminfo - print header information for application image 5265coninfo - print console devices and informations 5266ide - IDE sub-system 5267loop - infinite loop on address range 5268loopw - infinite write loop on address range 5269mtest - simple RAM test 5270icache - enable or disable instruction cache 5271dcache - enable or disable data cache 5272reset - Perform RESET of the CPU 5273echo - echo args to console 5274version - print monitor version 5275help - print online help 5276? - alias for 'help' 5277 5278 5279Monitor Commands - Detailed Description: 5280======================================== 5281 5282TODO. 5283 5284For now: just type "help <command>". 5285 5286 5287Environment Variables: 5288====================== 5289 5290U-Boot supports user configuration using Environment Variables which 5291can be made persistent by saving to Flash memory. 5292 5293Environment Variables are set using "setenv", printed using 5294"printenv", and saved to Flash using "saveenv". Using "setenv" 5295without a value can be used to delete a variable from the 5296environment. As long as you don't save the environment you are 5297working with an in-memory copy. In case the Flash area containing the 5298environment is erased by accident, a default environment is provided. 5299 5300Some configuration options can be set using Environment Variables. 5301 5302List of environment variables (most likely not complete): 5303 5304 baudrate - see CONFIG_BAUDRATE 5305 5306 bootdelay - see CONFIG_BOOTDELAY 5307 5308 bootcmd - see CONFIG_BOOTCOMMAND 5309 5310 bootargs - Boot arguments when booting an RTOS image 5311 5312 bootfile - Name of the image to load with TFTP 5313 5314 bootm_low - Memory range available for image processing in the bootm 5315 command can be restricted. This variable is given as 5316 a hexadecimal number and defines lowest address allowed 5317 for use by the bootm command. See also "bootm_size" 5318 environment variable. Address defined by "bootm_low" is 5319 also the base of the initial memory mapping for the Linux 5320 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 5321 bootm_mapsize. 5322 5323 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 5324 This variable is given as a hexadecimal number and it 5325 defines the size of the memory region starting at base 5326 address bootm_low that is accessible by the Linux kernel 5327 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 5328 as the default value if it is defined, and bootm_size is 5329 used otherwise. 5330 5331 bootm_size - Memory range available for image processing in the bootm 5332 command can be restricted. This variable is given as 5333 a hexadecimal number and defines the size of the region 5334 allowed for use by the bootm command. See also "bootm_low" 5335 environment variable. 5336 5337 updatefile - Location of the software update file on a TFTP server, used 5338 by the automatic software update feature. Please refer to 5339 documentation in doc/README.update for more details. 5340 5341 autoload - if set to "no" (any string beginning with 'n'), 5342 "bootp" will just load perform a lookup of the 5343 configuration from the BOOTP server, but not try to 5344 load any image using TFTP 5345 5346 autostart - if set to "yes", an image loaded using the "bootp", 5347 "rarpboot", "tftpboot" or "diskboot" commands will 5348 be automatically started (by internally calling 5349 "bootm") 5350 5351 If set to "no", a standalone image passed to the 5352 "bootm" command will be copied to the load address 5353 (and eventually uncompressed), but NOT be started. 5354 This can be used to load and uncompress arbitrary 5355 data. 5356 5357 fdt_high - if set this restricts the maximum address that the 5358 flattened device tree will be copied into upon boot. 5359 For example, if you have a system with 1 GB memory 5360 at physical address 0x10000000, while Linux kernel 5361 only recognizes the first 704 MB as low memory, you 5362 may need to set fdt_high as 0x3C000000 to have the 5363 device tree blob be copied to the maximum address 5364 of the 704 MB low memory, so that Linux kernel can 5365 access it during the boot procedure. 5366 5367 If this is set to the special value 0xFFFFFFFF then 5368 the fdt will not be copied at all on boot. For this 5369 to work it must reside in writable memory, have 5370 sufficient padding on the end of it for u-boot to 5371 add the information it needs into it, and the memory 5372 must be accessible by the kernel. 5373 5374 fdtcontroladdr- if set this is the address of the control flattened 5375 device tree used by U-Boot when CONFIG_OF_CONTROL is 5376 defined. 5377 5378 i2cfast - (PPC405GP|PPC405EP only) 5379 if set to 'y' configures Linux I2C driver for fast 5380 mode (400kHZ). This environment variable is used in 5381 initialization code. So, for changes to be effective 5382 it must be saved and board must be reset. 5383 5384 initrd_high - restrict positioning of initrd images: 5385 If this variable is not set, initrd images will be 5386 copied to the highest possible address in RAM; this 5387 is usually what you want since it allows for 5388 maximum initrd size. If for some reason you want to 5389 make sure that the initrd image is loaded below the 5390 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 5391 variable to a value of "no" or "off" or "0". 5392 Alternatively, you can set it to a maximum upper 5393 address to use (U-Boot will still check that it 5394 does not overwrite the U-Boot stack and data). 5395 5396 For instance, when you have a system with 16 MB 5397 RAM, and want to reserve 4 MB from use by Linux, 5398 you can do this by adding "mem=12M" to the value of 5399 the "bootargs" variable. However, now you must make 5400 sure that the initrd image is placed in the first 5401 12 MB as well - this can be done with 5402 5403 setenv initrd_high 00c00000 5404 5405 If you set initrd_high to 0xFFFFFFFF, this is an 5406 indication to U-Boot that all addresses are legal 5407 for the Linux kernel, including addresses in flash 5408 memory. In this case U-Boot will NOT COPY the 5409 ramdisk at all. This may be useful to reduce the 5410 boot time on your system, but requires that this 5411 feature is supported by your Linux kernel. 5412 5413 ipaddr - IP address; needed for tftpboot command 5414 5415 loadaddr - Default load address for commands like "bootp", 5416 "rarpboot", "tftpboot", "loadb" or "diskboot" 5417 5418 loads_echo - see CONFIG_LOADS_ECHO 5419 5420 serverip - TFTP server IP address; needed for tftpboot command 5421 5422 bootretry - see CONFIG_BOOT_RETRY_TIME 5423 5424 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 5425 5426 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 5427 5428 ethprime - controls which interface is used first. 5429 5430 ethact - controls which interface is currently active. 5431 For example you can do the following 5432 5433 => setenv ethact FEC 5434 => ping 192.168.0.1 # traffic sent on FEC 5435 => setenv ethact SCC 5436 => ping 10.0.0.1 # traffic sent on SCC 5437 5438 ethrotate - When set to "no" U-Boot does not go through all 5439 available network interfaces. 5440 It just stays at the currently selected interface. 5441 5442 netretry - When set to "no" each network operation will 5443 either succeed or fail without retrying. 5444 When set to "once" the network operation will 5445 fail when all the available network interfaces 5446 are tried once without success. 5447 Useful on scripts which control the retry operation 5448 themselves. 5449 5450 npe_ucode - set load address for the NPE microcode 5451 5452 silent_linux - If set then Linux will be told to boot silently, by 5453 changing the console to be empty. If "yes" it will be 5454 made silent. If "no" it will not be made silent. If 5455 unset, then it will be made silent if the U-Boot console 5456 is silent. 5457 5458 tftpsrcport - If this is set, the value is used for TFTP's 5459 UDP source port. 5460 5461 tftpdstport - If this is set, the value is used for TFTP's UDP 5462 destination port instead of the Well Know Port 69. 5463 5464 tftpblocksize - Block size to use for TFTP transfers; if not set, 5465 we use the TFTP server's default block size 5466 5467 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5468 seconds, minimum value is 1000 = 1 second). Defines 5469 when a packet is considered to be lost so it has to 5470 be retransmitted. The default is 5000 = 5 seconds. 5471 Lowering this value may make downloads succeed 5472 faster in networks with high packet loss rates or 5473 with unreliable TFTP servers. 5474 5475 vlan - When set to a value < 4095 the traffic over 5476 Ethernet is encapsulated/received over 802.1q 5477 VLAN tagged frames. 5478 5479The following image location variables contain the location of images 5480used in booting. The "Image" column gives the role of the image and is 5481not an environment variable name. The other columns are environment 5482variable names. "File Name" gives the name of the file on a TFTP 5483server, "RAM Address" gives the location in RAM the image will be 5484loaded to, and "Flash Location" gives the image's address in NOR 5485flash or offset in NAND flash. 5486 5487*Note* - these variables don't have to be defined for all boards, some 5488boards currenlty use other variables for these purposes, and some 5489boards use these variables for other purposes. 5490 5491Image File Name RAM Address Flash Location 5492----- --------- ----------- -------------- 5493u-boot u-boot u-boot_addr_r u-boot_addr 5494Linux kernel bootfile kernel_addr_r kernel_addr 5495device tree blob fdtfile fdt_addr_r fdt_addr 5496ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5497 5498The following environment variables may be used and automatically 5499updated by the network boot commands ("bootp" and "rarpboot"), 5500depending the information provided by your boot server: 5501 5502 bootfile - see above 5503 dnsip - IP address of your Domain Name Server 5504 dnsip2 - IP address of your secondary Domain Name Server 5505 gatewayip - IP address of the Gateway (Router) to use 5506 hostname - Target hostname 5507 ipaddr - see above 5508 netmask - Subnet Mask 5509 rootpath - Pathname of the root filesystem on the NFS server 5510 serverip - see above 5511 5512 5513There are two special Environment Variables: 5514 5515 serial# - contains hardware identification information such 5516 as type string and/or serial number 5517 ethaddr - Ethernet address 5518 5519These variables can be set only once (usually during manufacturing of 5520the board). U-Boot refuses to delete or overwrite these variables 5521once they have been set once. 5522 5523 5524Further special Environment Variables: 5525 5526 ver - Contains the U-Boot version string as printed 5527 with the "version" command. This variable is 5528 readonly (see CONFIG_VERSION_VARIABLE). 5529 5530 5531Please note that changes to some configuration parameters may take 5532only effect after the next boot (yes, that's just like Windoze :-). 5533 5534 5535Callback functions for environment variables: 5536--------------------------------------------- 5537 5538For some environment variables, the behavior of u-boot needs to change 5539when their values are changed. This functionality allows functions to 5540be associated with arbitrary variables. On creation, overwrite, or 5541deletion, the callback will provide the opportunity for some side 5542effect to happen or for the change to be rejected. 5543 5544The callbacks are named and associated with a function using the 5545U_BOOT_ENV_CALLBACK macro in your board or driver code. 5546 5547These callbacks are associated with variables in one of two ways. The 5548static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5549in the board configuration to a string that defines a list of 5550associations. The list must be in the following format: 5551 5552 entry = variable_name[:callback_name] 5553 list = entry[,list] 5554 5555If the callback name is not specified, then the callback is deleted. 5556Spaces are also allowed anywhere in the list. 5557 5558Callbacks can also be associated by defining the ".callbacks" variable 5559with the same list format above. Any association in ".callbacks" will 5560override any association in the static list. You can define 5561CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5562".callbacks" environment variable in the default or embedded environment. 5563 5564 5565Command Line Parsing: 5566===================== 5567 5568There are two different command line parsers available with U-Boot: 5569the old "simple" one, and the much more powerful "hush" shell: 5570 5571Old, simple command line parser: 5572-------------------------------- 5573 5574- supports environment variables (through setenv / saveenv commands) 5575- several commands on one line, separated by ';' 5576- variable substitution using "... ${name} ..." syntax 5577- special characters ('$', ';') can be escaped by prefixing with '\', 5578 for example: 5579 setenv bootcmd bootm \${address} 5580- You can also escape text by enclosing in single apostrophes, for example: 5581 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5582 5583Hush shell: 5584----------- 5585 5586- similar to Bourne shell, with control structures like 5587 if...then...else...fi, for...do...done; while...do...done, 5588 until...do...done, ... 5589- supports environment ("global") variables (through setenv / saveenv 5590 commands) and local shell variables (through standard shell syntax 5591 "name=value"); only environment variables can be used with "run" 5592 command 5593 5594General rules: 5595-------------- 5596 5597(1) If a command line (or an environment variable executed by a "run" 5598 command) contains several commands separated by semicolon, and 5599 one of these commands fails, then the remaining commands will be 5600 executed anyway. 5601 5602(2) If you execute several variables with one call to run (i. e. 5603 calling run with a list of variables as arguments), any failing 5604 command will cause "run" to terminate, i. e. the remaining 5605 variables are not executed. 5606 5607Note for Redundant Ethernet Interfaces: 5608======================================= 5609 5610Some boards come with redundant Ethernet interfaces; U-Boot supports 5611such configurations and is capable of automatic selection of a 5612"working" interface when needed. MAC assignment works as follows: 5613 5614Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5615MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5616"eth1addr" (=>eth1), "eth2addr", ... 5617 5618If the network interface stores some valid MAC address (for instance 5619in SROM), this is used as default address if there is NO correspon- 5620ding setting in the environment; if the corresponding environment 5621variable is set, this overrides the settings in the card; that means: 5622 5623o If the SROM has a valid MAC address, and there is no address in the 5624 environment, the SROM's address is used. 5625 5626o If there is no valid address in the SROM, and a definition in the 5627 environment exists, then the value from the environment variable is 5628 used. 5629 5630o If both the SROM and the environment contain a MAC address, and 5631 both addresses are the same, this MAC address is used. 5632 5633o If both the SROM and the environment contain a MAC address, and the 5634 addresses differ, the value from the environment is used and a 5635 warning is printed. 5636 5637o If neither SROM nor the environment contain a MAC address, an error 5638 is raised. 5639 5640If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5641will be programmed into hardware as part of the initialization process. This 5642may be skipped by setting the appropriate 'ethmacskip' environment variable. 5643The naming convention is as follows: 5644"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5645 5646Image Formats: 5647============== 5648 5649U-Boot is capable of booting (and performing other auxiliary operations on) 5650images in two formats: 5651 5652New uImage format (FIT) 5653----------------------- 5654 5655Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5656to Flattened Device Tree). It allows the use of images with multiple 5657components (several kernels, ramdisks, etc.), with contents protected by 5658SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5659 5660 5661Old uImage format 5662----------------- 5663 5664Old image format is based on binary files which can be basically anything, 5665preceded by a special header; see the definitions in include/image.h for 5666details; basically, the header defines the following image properties: 5667 5668* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5669 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5670 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5671 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5672 INTEGRITY). 5673* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5674 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5675 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5676* Compression Type (uncompressed, gzip, bzip2) 5677* Load Address 5678* Entry Point 5679* Image Name 5680* Image Timestamp 5681 5682The header is marked by a special Magic Number, and both the header 5683and the data portions of the image are secured against corruption by 5684CRC32 checksums. 5685 5686 5687Linux Support: 5688============== 5689 5690Although U-Boot should support any OS or standalone application 5691easily, the main focus has always been on Linux during the design of 5692U-Boot. 5693 5694U-Boot includes many features that so far have been part of some 5695special "boot loader" code within the Linux kernel. Also, any 5696"initrd" images to be used are no longer part of one big Linux image; 5697instead, kernel and "initrd" are separate images. This implementation 5698serves several purposes: 5699 5700- the same features can be used for other OS or standalone 5701 applications (for instance: using compressed images to reduce the 5702 Flash memory footprint) 5703 5704- it becomes much easier to port new Linux kernel versions because 5705 lots of low-level, hardware dependent stuff are done by U-Boot 5706 5707- the same Linux kernel image can now be used with different "initrd" 5708 images; of course this also means that different kernel images can 5709 be run with the same "initrd". This makes testing easier (you don't 5710 have to build a new "zImage.initrd" Linux image when you just 5711 change a file in your "initrd"). Also, a field-upgrade of the 5712 software is easier now. 5713 5714 5715Linux HOWTO: 5716============ 5717 5718Porting Linux to U-Boot based systems: 5719--------------------------------------- 5720 5721U-Boot cannot save you from doing all the necessary modifications to 5722configure the Linux device drivers for use with your target hardware 5723(no, we don't intend to provide a full virtual machine interface to 5724Linux :-). 5725 5726But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5727 5728Just make sure your machine specific header file (for instance 5729include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5730Information structure as we define in include/asm-<arch>/u-boot.h, 5731and make sure that your definition of IMAP_ADDR uses the same value 5732as your U-Boot configuration in CONFIG_SYS_IMMR. 5733 5734Note that U-Boot now has a driver model, a unified model for drivers. 5735If you are adding a new driver, plumb it into driver model. If there 5736is no uclass available, you are encouraged to create one. See 5737doc/driver-model. 5738 5739 5740Configuring the Linux kernel: 5741----------------------------- 5742 5743No specific requirements for U-Boot. Make sure you have some root 5744device (initial ramdisk, NFS) for your target system. 5745 5746 5747Building a Linux Image: 5748----------------------- 5749 5750With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5751not used. If you use recent kernel source, a new build target 5752"uImage" will exist which automatically builds an image usable by 5753U-Boot. Most older kernels also have support for a "pImage" target, 5754which was introduced for our predecessor project PPCBoot and uses a 5755100% compatible format. 5756 5757Example: 5758 5759 make TQM850L_defconfig 5760 make oldconfig 5761 make dep 5762 make uImage 5763 5764The "uImage" build target uses a special tool (in 'tools/mkimage') to 5765encapsulate a compressed Linux kernel image with header information, 5766CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5767 5768* build a standard "vmlinux" kernel image (in ELF binary format): 5769 5770* convert the kernel into a raw binary image: 5771 5772 ${CROSS_COMPILE}-objcopy -O binary \ 5773 -R .note -R .comment \ 5774 -S vmlinux linux.bin 5775 5776* compress the binary image: 5777 5778 gzip -9 linux.bin 5779 5780* package compressed binary image for U-Boot: 5781 5782 mkimage -A ppc -O linux -T kernel -C gzip \ 5783 -a 0 -e 0 -n "Linux Kernel Image" \ 5784 -d linux.bin.gz uImage 5785 5786 5787The "mkimage" tool can also be used to create ramdisk images for use 5788with U-Boot, either separated from the Linux kernel image, or 5789combined into one file. "mkimage" encapsulates the images with a 64 5790byte header containing information about target architecture, 5791operating system, image type, compression method, entry points, time 5792stamp, CRC32 checksums, etc. 5793 5794"mkimage" can be called in two ways: to verify existing images and 5795print the header information, or to build new images. 5796 5797In the first form (with "-l" option) mkimage lists the information 5798contained in the header of an existing U-Boot image; this includes 5799checksum verification: 5800 5801 tools/mkimage -l image 5802 -l ==> list image header information 5803 5804The second form (with "-d" option) is used to build a U-Boot image 5805from a "data file" which is used as image payload: 5806 5807 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5808 -n name -d data_file image 5809 -A ==> set architecture to 'arch' 5810 -O ==> set operating system to 'os' 5811 -T ==> set image type to 'type' 5812 -C ==> set compression type 'comp' 5813 -a ==> set load address to 'addr' (hex) 5814 -e ==> set entry point to 'ep' (hex) 5815 -n ==> set image name to 'name' 5816 -d ==> use image data from 'datafile' 5817 5818Right now, all Linux kernels for PowerPC systems use the same load 5819address (0x00000000), but the entry point address depends on the 5820kernel version: 5821 5822- 2.2.x kernels have the entry point at 0x0000000C, 5823- 2.3.x and later kernels have the entry point at 0x00000000. 5824 5825So a typical call to build a U-Boot image would read: 5826 5827 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5828 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5829 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5830 > examples/uImage.TQM850L 5831 Image Name: 2.4.4 kernel for TQM850L 5832 Created: Wed Jul 19 02:34:59 2000 5833 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5834 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5835 Load Address: 0x00000000 5836 Entry Point: 0x00000000 5837 5838To verify the contents of the image (or check for corruption): 5839 5840 -> tools/mkimage -l examples/uImage.TQM850L 5841 Image Name: 2.4.4 kernel for TQM850L 5842 Created: Wed Jul 19 02:34:59 2000 5843 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5844 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5845 Load Address: 0x00000000 5846 Entry Point: 0x00000000 5847 5848NOTE: for embedded systems where boot time is critical you can trade 5849speed for memory and install an UNCOMPRESSED image instead: this 5850needs more space in Flash, but boots much faster since it does not 5851need to be uncompressed: 5852 5853 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5854 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5855 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5856 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5857 > examples/uImage.TQM850L-uncompressed 5858 Image Name: 2.4.4 kernel for TQM850L 5859 Created: Wed Jul 19 02:34:59 2000 5860 Image Type: PowerPC Linux Kernel Image (uncompressed) 5861 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5862 Load Address: 0x00000000 5863 Entry Point: 0x00000000 5864 5865 5866Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5867when your kernel is intended to use an initial ramdisk: 5868 5869 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5870 > -A ppc -O linux -T ramdisk -C gzip \ 5871 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5872 Image Name: Simple Ramdisk Image 5873 Created: Wed Jan 12 14:01:50 2000 5874 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5875 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5876 Load Address: 0x00000000 5877 Entry Point: 0x00000000 5878 5879The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5880option performs the converse operation of the mkimage's second form (the "-d" 5881option). Given an image built by mkimage, the dumpimage extracts a "data file" 5882from the image: 5883 5884 tools/dumpimage -i image -T type -p position data_file 5885 -i ==> extract from the 'image' a specific 'data_file' 5886 -T ==> set image type to 'type' 5887 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5888 5889 5890Installing a Linux Image: 5891------------------------- 5892 5893To downloading a U-Boot image over the serial (console) interface, 5894you must convert the image to S-Record format: 5895 5896 objcopy -I binary -O srec examples/image examples/image.srec 5897 5898The 'objcopy' does not understand the information in the U-Boot 5899image header, so the resulting S-Record file will be relative to 5900address 0x00000000. To load it to a given address, you need to 5901specify the target address as 'offset' parameter with the 'loads' 5902command. 5903 5904Example: install the image to address 0x40100000 (which on the 5905TQM8xxL is in the first Flash bank): 5906 5907 => erase 40100000 401FFFFF 5908 5909 .......... done 5910 Erased 8 sectors 5911 5912 => loads 40100000 5913 ## Ready for S-Record download ... 5914 ~>examples/image.srec 5915 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5916 ... 5917 15989 15990 15991 15992 5918 [file transfer complete] 5919 [connected] 5920 ## Start Addr = 0x00000000 5921 5922 5923You can check the success of the download using the 'iminfo' command; 5924this includes a checksum verification so you can be sure no data 5925corruption happened: 5926 5927 => imi 40100000 5928 5929 ## Checking Image at 40100000 ... 5930 Image Name: 2.2.13 for initrd on TQM850L 5931 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5932 Data Size: 335725 Bytes = 327 kB = 0 MB 5933 Load Address: 00000000 5934 Entry Point: 0000000c 5935 Verifying Checksum ... OK 5936 5937 5938Boot Linux: 5939----------- 5940 5941The "bootm" command is used to boot an application that is stored in 5942memory (RAM or Flash). In case of a Linux kernel image, the contents 5943of the "bootargs" environment variable is passed to the kernel as 5944parameters. You can check and modify this variable using the 5945"printenv" and "setenv" commands: 5946 5947 5948 => printenv bootargs 5949 bootargs=root=/dev/ram 5950 5951 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5952 5953 => printenv bootargs 5954 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5955 5956 => bootm 40020000 5957 ## Booting Linux kernel at 40020000 ... 5958 Image Name: 2.2.13 for NFS on TQM850L 5959 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5960 Data Size: 381681 Bytes = 372 kB = 0 MB 5961 Load Address: 00000000 5962 Entry Point: 0000000c 5963 Verifying Checksum ... OK 5964 Uncompressing Kernel Image ... OK 5965 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 5966 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5967 time_init: decrementer frequency = 187500000/60 5968 Calibrating delay loop... 49.77 BogoMIPS 5969 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5970 ... 5971 5972If you want to boot a Linux kernel with initial RAM disk, you pass 5973the memory addresses of both the kernel and the initrd image (PPBCOOT 5974format!) to the "bootm" command: 5975 5976 => imi 40100000 40200000 5977 5978 ## Checking Image at 40100000 ... 5979 Image Name: 2.2.13 for initrd on TQM850L 5980 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5981 Data Size: 335725 Bytes = 327 kB = 0 MB 5982 Load Address: 00000000 5983 Entry Point: 0000000c 5984 Verifying Checksum ... OK 5985 5986 ## Checking Image at 40200000 ... 5987 Image Name: Simple Ramdisk Image 5988 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5989 Data Size: 566530 Bytes = 553 kB = 0 MB 5990 Load Address: 00000000 5991 Entry Point: 00000000 5992 Verifying Checksum ... OK 5993 5994 => bootm 40100000 40200000 5995 ## Booting Linux kernel at 40100000 ... 5996 Image Name: 2.2.13 for initrd on TQM850L 5997 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5998 Data Size: 335725 Bytes = 327 kB = 0 MB 5999 Load Address: 00000000 6000 Entry Point: 0000000c 6001 Verifying Checksum ... OK 6002 Uncompressing Kernel Image ... OK 6003 ## Loading RAMDisk Image at 40200000 ... 6004 Image Name: Simple Ramdisk Image 6005 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 6006 Data Size: 566530 Bytes = 553 kB = 0 MB 6007 Load Address: 00000000 6008 Entry Point: 00000000 6009 Verifying Checksum ... OK 6010 Loading Ramdisk ... OK 6011 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 6012 Boot arguments: root=/dev/ram 6013 time_init: decrementer frequency = 187500000/60 6014 Calibrating delay loop... 49.77 BogoMIPS 6015 ... 6016 RAMDISK: Compressed image found at block 0 6017 VFS: Mounted root (ext2 filesystem). 6018 6019 bash# 6020 6021Boot Linux and pass a flat device tree: 6022----------- 6023 6024First, U-Boot must be compiled with the appropriate defines. See the section 6025titled "Linux Kernel Interface" above for a more in depth explanation. The 6026following is an example of how to start a kernel and pass an updated 6027flat device tree: 6028 6029=> print oftaddr 6030oftaddr=0x300000 6031=> print oft 6032oft=oftrees/mpc8540ads.dtb 6033=> tftp $oftaddr $oft 6034Speed: 1000, full duplex 6035Using TSEC0 device 6036TFTP from server 192.168.1.1; our IP address is 192.168.1.101 6037Filename 'oftrees/mpc8540ads.dtb'. 6038Load address: 0x300000 6039Loading: # 6040done 6041Bytes transferred = 4106 (100a hex) 6042=> tftp $loadaddr $bootfile 6043Speed: 1000, full duplex 6044Using TSEC0 device 6045TFTP from server 192.168.1.1; our IP address is 192.168.1.2 6046Filename 'uImage'. 6047Load address: 0x200000 6048Loading:############ 6049done 6050Bytes transferred = 1029407 (fb51f hex) 6051=> print loadaddr 6052loadaddr=200000 6053=> print oftaddr 6054oftaddr=0x300000 6055=> bootm $loadaddr - $oftaddr 6056## Booting image at 00200000 ... 6057 Image Name: Linux-2.6.17-dirty 6058 Image Type: PowerPC Linux Kernel Image (gzip compressed) 6059 Data Size: 1029343 Bytes = 1005.2 kB 6060 Load Address: 00000000 6061 Entry Point: 00000000 6062 Verifying Checksum ... OK 6063 Uncompressing Kernel Image ... OK 6064Booting using flat device tree at 0x300000 6065Using MPC85xx ADS machine description 6066Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 6067[snip] 6068 6069 6070More About U-Boot Image Types: 6071------------------------------ 6072 6073U-Boot supports the following image types: 6074 6075 "Standalone Programs" are directly runnable in the environment 6076 provided by U-Boot; it is expected that (if they behave 6077 well) you can continue to work in U-Boot after return from 6078 the Standalone Program. 6079 "OS Kernel Images" are usually images of some Embedded OS which 6080 will take over control completely. Usually these programs 6081 will install their own set of exception handlers, device 6082 drivers, set up the MMU, etc. - this means, that you cannot 6083 expect to re-enter U-Boot except by resetting the CPU. 6084 "RAMDisk Images" are more or less just data blocks, and their 6085 parameters (address, size) are passed to an OS kernel that is 6086 being started. 6087 "Multi-File Images" contain several images, typically an OS 6088 (Linux) kernel image and one or more data images like 6089 RAMDisks. This construct is useful for instance when you want 6090 to boot over the network using BOOTP etc., where the boot 6091 server provides just a single image file, but you want to get 6092 for instance an OS kernel and a RAMDisk image. 6093 6094 "Multi-File Images" start with a list of image sizes, each 6095 image size (in bytes) specified by an "uint32_t" in network 6096 byte order. This list is terminated by an "(uint32_t)0". 6097 Immediately after the terminating 0 follow the images, one by 6098 one, all aligned on "uint32_t" boundaries (size rounded up to 6099 a multiple of 4 bytes). 6100 6101 "Firmware Images" are binary images containing firmware (like 6102 U-Boot or FPGA images) which usually will be programmed to 6103 flash memory. 6104 6105 "Script files" are command sequences that will be executed by 6106 U-Boot's command interpreter; this feature is especially 6107 useful when you configure U-Boot to use a real shell (hush) 6108 as command interpreter. 6109 6110Booting the Linux zImage: 6111------------------------- 6112 6113On some platforms, it's possible to boot Linux zImage. This is done 6114using the "bootz" command. The syntax of "bootz" command is the same 6115as the syntax of "bootm" command. 6116 6117Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 6118kernel with raw initrd images. The syntax is slightly different, the 6119address of the initrd must be augmented by it's size, in the following 6120format: "<initrd addres>:<initrd size>". 6121 6122 6123Standalone HOWTO: 6124================= 6125 6126One of the features of U-Boot is that you can dynamically load and 6127run "standalone" applications, which can use some resources of 6128U-Boot like console I/O functions or interrupt services. 6129 6130Two simple examples are included with the sources: 6131 6132"Hello World" Demo: 6133------------------- 6134 6135'examples/hello_world.c' contains a small "Hello World" Demo 6136application; it is automatically compiled when you build U-Boot. 6137It's configured to run at address 0x00040004, so you can play with it 6138like that: 6139 6140 => loads 6141 ## Ready for S-Record download ... 6142 ~>examples/hello_world.srec 6143 1 2 3 4 5 6 7 8 9 10 11 ... 6144 [file transfer complete] 6145 [connected] 6146 ## Start Addr = 0x00040004 6147 6148 => go 40004 Hello World! This is a test. 6149 ## Starting application at 0x00040004 ... 6150 Hello World 6151 argc = 7 6152 argv[0] = "40004" 6153 argv[1] = "Hello" 6154 argv[2] = "World!" 6155 argv[3] = "This" 6156 argv[4] = "is" 6157 argv[5] = "a" 6158 argv[6] = "test." 6159 argv[7] = "<NULL>" 6160 Hit any key to exit ... 6161 6162 ## Application terminated, rc = 0x0 6163 6164Another example, which demonstrates how to register a CPM interrupt 6165handler with the U-Boot code, can be found in 'examples/timer.c'. 6166Here, a CPM timer is set up to generate an interrupt every second. 6167The interrupt service routine is trivial, just printing a '.' 6168character, but this is just a demo program. The application can be 6169controlled by the following keys: 6170 6171 ? - print current values og the CPM Timer registers 6172 b - enable interrupts and start timer 6173 e - stop timer and disable interrupts 6174 q - quit application 6175 6176 => loads 6177 ## Ready for S-Record download ... 6178 ~>examples/timer.srec 6179 1 2 3 4 5 6 7 8 9 10 11 ... 6180 [file transfer complete] 6181 [connected] 6182 ## Start Addr = 0x00040004 6183 6184 => go 40004 6185 ## Starting application at 0x00040004 ... 6186 TIMERS=0xfff00980 6187 Using timer 1 6188 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 6189 6190Hit 'b': 6191 [q, b, e, ?] Set interval 1000000 us 6192 Enabling timer 6193Hit '?': 6194 [q, b, e, ?] ........ 6195 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 6196Hit '?': 6197 [q, b, e, ?] . 6198 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 6199Hit '?': 6200 [q, b, e, ?] . 6201 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 6202Hit '?': 6203 [q, b, e, ?] . 6204 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 6205Hit 'e': 6206 [q, b, e, ?] ...Stopping timer 6207Hit 'q': 6208 [q, b, e, ?] ## Application terminated, rc = 0x0 6209 6210 6211Minicom warning: 6212================ 6213 6214Over time, many people have reported problems when trying to use the 6215"minicom" terminal emulation program for serial download. I (wd) 6216consider minicom to be broken, and recommend not to use it. Under 6217Unix, I recommend to use C-Kermit for general purpose use (and 6218especially for kermit binary protocol download ("loadb" command), and 6219use "cu" for S-Record download ("loads" command). See 6220http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 6221for help with kermit. 6222 6223 6224Nevertheless, if you absolutely want to use it try adding this 6225configuration to your "File transfer protocols" section: 6226 6227 Name Program Name U/D FullScr IO-Red. Multi 6228 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 6229 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 6230 6231 6232NetBSD Notes: 6233============= 6234 6235Starting at version 0.9.2, U-Boot supports NetBSD both as host 6236(build U-Boot) and target system (boots NetBSD/mpc8xx). 6237 6238Building requires a cross environment; it is known to work on 6239NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 6240need gmake since the Makefiles are not compatible with BSD make). 6241Note that the cross-powerpc package does not install include files; 6242attempting to build U-Boot will fail because <machine/ansi.h> is 6243missing. This file has to be installed and patched manually: 6244 6245 # cd /usr/pkg/cross/powerpc-netbsd/include 6246 # mkdir powerpc 6247 # ln -s powerpc machine 6248 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 6249 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 6250 6251Native builds *don't* work due to incompatibilities between native 6252and U-Boot include files. 6253 6254Booting assumes that (the first part of) the image booted is a 6255stage-2 loader which in turn loads and then invokes the kernel 6256proper. Loader sources will eventually appear in the NetBSD source 6257tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 6258meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 6259 6260 6261Implementation Internals: 6262========================= 6263 6264The following is not intended to be a complete description of every 6265implementation detail. However, it should help to understand the 6266inner workings of U-Boot and make it easier to port it to custom 6267hardware. 6268 6269 6270Initial Stack, Global Data: 6271--------------------------- 6272 6273The implementation of U-Boot is complicated by the fact that U-Boot 6274starts running out of ROM (flash memory), usually without access to 6275system RAM (because the memory controller is not initialized yet). 6276This means that we don't have writable Data or BSS segments, and BSS 6277is not initialized as zero. To be able to get a C environment working 6278at all, we have to allocate at least a minimal stack. Implementation 6279options for this are defined and restricted by the CPU used: Some CPU 6280models provide on-chip memory (like the IMMR area on MPC8xx and 6281MPC826x processors), on others (parts of) the data cache can be 6282locked as (mis-) used as memory, etc. 6283 6284 Chris Hallinan posted a good summary of these issues to the 6285 U-Boot mailing list: 6286 6287 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 6288 From: "Chris Hallinan" <clh@net1plus.com> 6289 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 6290 ... 6291 6292 Correct me if I'm wrong, folks, but the way I understand it 6293 is this: Using DCACHE as initial RAM for Stack, etc, does not 6294 require any physical RAM backing up the cache. The cleverness 6295 is that the cache is being used as a temporary supply of 6296 necessary storage before the SDRAM controller is setup. It's 6297 beyond the scope of this list to explain the details, but you 6298 can see how this works by studying the cache architecture and 6299 operation in the architecture and processor-specific manuals. 6300 6301 OCM is On Chip Memory, which I believe the 405GP has 4K. It 6302 is another option for the system designer to use as an 6303 initial stack/RAM area prior to SDRAM being available. Either 6304 option should work for you. Using CS 4 should be fine if your 6305 board designers haven't used it for something that would 6306 cause you grief during the initial boot! It is frequently not 6307 used. 6308 6309 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 6310 with your processor/board/system design. The default value 6311 you will find in any recent u-boot distribution in 6312 walnut.h should work for you. I'd set it to a value larger 6313 than your SDRAM module. If you have a 64MB SDRAM module, set 6314 it above 400_0000. Just make sure your board has no resources 6315 that are supposed to respond to that address! That code in 6316 start.S has been around a while and should work as is when 6317 you get the config right. 6318 6319 -Chris Hallinan 6320 DS4.COM, Inc. 6321 6322It is essential to remember this, since it has some impact on the C 6323code for the initialization procedures: 6324 6325* Initialized global data (data segment) is read-only. Do not attempt 6326 to write it. 6327 6328* Do not use any uninitialized global data (or implicitly initialized 6329 as zero data - BSS segment) at all - this is undefined, initiali- 6330 zation is performed later (when relocating to RAM). 6331 6332* Stack space is very limited. Avoid big data buffers or things like 6333 that. 6334 6335Having only the stack as writable memory limits means we cannot use 6336normal global data to share information between the code. But it 6337turned out that the implementation of U-Boot can be greatly 6338simplified by making a global data structure (gd_t) available to all 6339functions. We could pass a pointer to this data as argument to _all_ 6340functions, but this would bloat the code. Instead we use a feature of 6341the GCC compiler (Global Register Variables) to share the data: we 6342place a pointer (gd) to the global data into a register which we 6343reserve for this purpose. 6344 6345When choosing a register for such a purpose we are restricted by the 6346relevant (E)ABI specifications for the current architecture, and by 6347GCC's implementation. 6348 6349For PowerPC, the following registers have specific use: 6350 R1: stack pointer 6351 R2: reserved for system use 6352 R3-R4: parameter passing and return values 6353 R5-R10: parameter passing 6354 R13: small data area pointer 6355 R30: GOT pointer 6356 R31: frame pointer 6357 6358 (U-Boot also uses R12 as internal GOT pointer. r12 6359 is a volatile register so r12 needs to be reset when 6360 going back and forth between asm and C) 6361 6362 ==> U-Boot will use R2 to hold a pointer to the global data 6363 6364 Note: on PPC, we could use a static initializer (since the 6365 address of the global data structure is known at compile time), 6366 but it turned out that reserving a register results in somewhat 6367 smaller code - although the code savings are not that big (on 6368 average for all boards 752 bytes for the whole U-Boot image, 6369 624 text + 127 data). 6370 6371On Blackfin, the normal C ABI (except for P3) is followed as documented here: 6372 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 6373 6374 ==> U-Boot will use P3 to hold a pointer to the global data 6375 6376On ARM, the following registers are used: 6377 6378 R0: function argument word/integer result 6379 R1-R3: function argument word 6380 R9: platform specific 6381 R10: stack limit (used only if stack checking is enabled) 6382 R11: argument (frame) pointer 6383 R12: temporary workspace 6384 R13: stack pointer 6385 R14: link register 6386 R15: program counter 6387 6388 ==> U-Boot will use R9 to hold a pointer to the global data 6389 6390 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 6391 6392On Nios II, the ABI is documented here: 6393 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 6394 6395 ==> U-Boot will use gp to hold a pointer to the global data 6396 6397 Note: on Nios II, we give "-G0" option to gcc and don't use gp 6398 to access small data sections, so gp is free. 6399 6400On NDS32, the following registers are used: 6401 6402 R0-R1: argument/return 6403 R2-R5: argument 6404 R15: temporary register for assembler 6405 R16: trampoline register 6406 R28: frame pointer (FP) 6407 R29: global pointer (GP) 6408 R30: link register (LP) 6409 R31: stack pointer (SP) 6410 PC: program counter (PC) 6411 6412 ==> U-Boot will use R10 to hold a pointer to the global data 6413 6414NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 6415or current versions of GCC may "optimize" the code too much. 6416 6417Memory Management: 6418------------------ 6419 6420U-Boot runs in system state and uses physical addresses, i.e. the 6421MMU is not used either for address mapping nor for memory protection. 6422 6423The available memory is mapped to fixed addresses using the memory 6424controller. In this process, a contiguous block is formed for each 6425memory type (Flash, SDRAM, SRAM), even when it consists of several 6426physical memory banks. 6427 6428U-Boot is installed in the first 128 kB of the first Flash bank (on 6429TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 6430booting and sizing and initializing DRAM, the code relocates itself 6431to the upper end of DRAM. Immediately below the U-Boot code some 6432memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 6433configuration setting]. Below that, a structure with global Board 6434Info data is placed, followed by the stack (growing downward). 6435 6436Additionally, some exception handler code is copied to the low 8 kB 6437of DRAM (0x00000000 ... 0x00001FFF). 6438 6439So a typical memory configuration with 16 MB of DRAM could look like 6440this: 6441 6442 0x0000 0000 Exception Vector code 6443 : 6444 0x0000 1FFF 6445 0x0000 2000 Free for Application Use 6446 : 6447 : 6448 6449 : 6450 : 6451 0x00FB FF20 Monitor Stack (Growing downward) 6452 0x00FB FFAC Board Info Data and permanent copy of global data 6453 0x00FC 0000 Malloc Arena 6454 : 6455 0x00FD FFFF 6456 0x00FE 0000 RAM Copy of Monitor Code 6457 ... eventually: LCD or video framebuffer 6458 ... eventually: pRAM (Protected RAM - unchanged by reset) 6459 0x00FF FFFF [End of RAM] 6460 6461 6462System Initialization: 6463---------------------- 6464 6465In the reset configuration, U-Boot starts at the reset entry point 6466(on most PowerPC systems at address 0x00000100). Because of the reset 6467configuration for CS0# this is a mirror of the on board Flash memory. 6468To be able to re-map memory U-Boot then jumps to its link address. 6469To be able to implement the initialization code in C, a (small!) 6470initial stack is set up in the internal Dual Ported RAM (in case CPUs 6471which provide such a feature like MPC8xx or MPC8260), or in a locked 6472part of the data cache. After that, U-Boot initializes the CPU core, 6473the caches and the SIU. 6474 6475Next, all (potentially) available memory banks are mapped using a 6476preliminary mapping. For example, we put them on 512 MB boundaries 6477(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6478on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6479programmed for SDRAM access. Using the temporary configuration, a 6480simple memory test is run that determines the size of the SDRAM 6481banks. 6482 6483When there is more than one SDRAM bank, and the banks are of 6484different size, the largest is mapped first. For equal size, the first 6485bank (CS2#) is mapped first. The first mapping is always for address 64860x00000000, with any additional banks following immediately to create 6487contiguous memory starting from 0. 6488 6489Then, the monitor installs itself at the upper end of the SDRAM area 6490and allocates memory for use by malloc() and for the global Board 6491Info data; also, the exception vector code is copied to the low RAM 6492pages, and the final stack is set up. 6493 6494Only after this relocation will you have a "normal" C environment; 6495until that you are restricted in several ways, mostly because you are 6496running from ROM, and because the code will have to be relocated to a 6497new address in RAM. 6498 6499 6500U-Boot Porting Guide: 6501---------------------- 6502 6503[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6504list, October 2002] 6505 6506 6507int main(int argc, char *argv[]) 6508{ 6509 sighandler_t no_more_time; 6510 6511 signal(SIGALRM, no_more_time); 6512 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6513 6514 if (available_money > available_manpower) { 6515 Pay consultant to port U-Boot; 6516 return 0; 6517 } 6518 6519 Download latest U-Boot source; 6520 6521 Subscribe to u-boot mailing list; 6522 6523 if (clueless) 6524 email("Hi, I am new to U-Boot, how do I get started?"); 6525 6526 while (learning) { 6527 Read the README file in the top level directory; 6528 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6529 Read applicable doc/*.README; 6530 Read the source, Luke; 6531 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6532 } 6533 6534 if (available_money > toLocalCurrency ($2500)) 6535 Buy a BDI3000; 6536 else 6537 Add a lot of aggravation and time; 6538 6539 if (a similar board exists) { /* hopefully... */ 6540 cp -a board/<similar> board/<myboard> 6541 cp include/configs/<similar>.h include/configs/<myboard>.h 6542 } else { 6543 Create your own board support subdirectory; 6544 Create your own board include/configs/<myboard>.h file; 6545 } 6546 Edit new board/<myboard> files 6547 Edit new include/configs/<myboard>.h 6548 6549 while (!accepted) { 6550 while (!running) { 6551 do { 6552 Add / modify source code; 6553 } until (compiles); 6554 Debug; 6555 if (clueless) 6556 email("Hi, I am having problems..."); 6557 } 6558 Send patch file to the U-Boot email list; 6559 if (reasonable critiques) 6560 Incorporate improvements from email list code review; 6561 else 6562 Defend code as written; 6563 } 6564 6565 return 0; 6566} 6567 6568void no_more_time (int sig) 6569{ 6570 hire_a_guru(); 6571} 6572 6573 6574Coding Standards: 6575----------------- 6576 6577All contributions to U-Boot should conform to the Linux kernel 6578coding style; see the file "Documentation/CodingStyle" and the script 6579"scripts/Lindent" in your Linux kernel source directory. 6580 6581Source files originating from a different project (for example the 6582MTD subsystem) are generally exempt from these guidelines and are not 6583reformatted to ease subsequent migration to newer versions of those 6584sources. 6585 6586Please note that U-Boot is implemented in C (and to some small parts in 6587Assembler); no C++ is used, so please do not use C++ style comments (//) 6588in your code. 6589 6590Please also stick to the following formatting rules: 6591- remove any trailing white space 6592- use TAB characters for indentation and vertical alignment, not spaces 6593- make sure NOT to use DOS '\r\n' line feeds 6594- do not add more than 2 consecutive empty lines to source files 6595- do not add trailing empty lines to source files 6596 6597Submissions which do not conform to the standards may be returned 6598with a request to reformat the changes. 6599 6600 6601Submitting Patches: 6602------------------- 6603 6604Since the number of patches for U-Boot is growing, we need to 6605establish some rules. Submissions which do not conform to these rules 6606may be rejected, even when they contain important and valuable stuff. 6607 6608Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6609 6610Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6611see http://lists.denx.de/mailman/listinfo/u-boot 6612 6613When you send a patch, please include the following information with 6614it: 6615 6616* For bug fixes: a description of the bug and how your patch fixes 6617 this bug. Please try to include a way of demonstrating that the 6618 patch actually fixes something. 6619 6620* For new features: a description of the feature and your 6621 implementation. 6622 6623* A CHANGELOG entry as plaintext (separate from the patch) 6624 6625* For major contributions, your entry to the CREDITS file 6626 6627* When you add support for a new board, don't forget to add a 6628 maintainer e-mail address to the boards.cfg file, too. 6629 6630* If your patch adds new configuration options, don't forget to 6631 document these in the README file. 6632 6633* The patch itself. If you are using git (which is *strongly* 6634 recommended) you can easily generate the patch using the 6635 "git format-patch". If you then use "git send-email" to send it to 6636 the U-Boot mailing list, you will avoid most of the common problems 6637 with some other mail clients. 6638 6639 If you cannot use git, use "diff -purN OLD NEW". If your version of 6640 diff does not support these options, then get the latest version of 6641 GNU diff. 6642 6643 The current directory when running this command shall be the parent 6644 directory of the U-Boot source tree (i. e. please make sure that 6645 your patch includes sufficient directory information for the 6646 affected files). 6647 6648 We prefer patches as plain text. MIME attachments are discouraged, 6649 and compressed attachments must not be used. 6650 6651* If one logical set of modifications affects or creates several 6652 files, all these changes shall be submitted in a SINGLE patch file. 6653 6654* Changesets that contain different, unrelated modifications shall be 6655 submitted as SEPARATE patches, one patch per changeset. 6656 6657 6658Notes: 6659 6660* Before sending the patch, run the MAKEALL script on your patched 6661 source tree and make sure that no errors or warnings are reported 6662 for any of the boards. 6663 6664* Keep your modifications to the necessary minimum: A patch 6665 containing several unrelated changes or arbitrary reformats will be 6666 returned with a request to re-formatting / split it. 6667 6668* If you modify existing code, make sure that your new code does not 6669 add to the memory footprint of the code ;-) Small is beautiful! 6670 When adding new features, these should compile conditionally only 6671 (using #ifdef), and the resulting code with the new feature 6672 disabled must not need more memory than the old code without your 6673 modification. 6674 6675* Remember that there is a size limit of 100 kB per message on the 6676 u-boot mailing list. Bigger patches will be moderated. If they are 6677 reasonable and not too big, they will be acknowledged. But patches 6678 bigger than the size limit should be avoided. 6679