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 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 186 /mpc5xx Files specific to Freescale MPC5xx CPUs 187 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 188 /mpc8xx Files specific to Freescale MPC8xx CPUs 189 /mpc824x Files specific to Freescale MPC824x CPUs 190 /mpc8260 Files specific to Freescale MPC8260 CPUs 191 /mpc85xx Files specific to Freescale MPC85xx CPUs 192 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 193 /lib Architecture specific library files 194 /sh Files generic to SH architecture 195 /cpu CPU specific files 196 /sh2 Files specific to sh2 CPUs 197 /sh3 Files specific to sh3 CPUs 198 /sh4 Files specific to sh4 CPUs 199 /lib Architecture specific library files 200 /sparc Files generic to SPARC architecture 201 /cpu CPU specific files 202 /leon2 Files specific to Gaisler LEON2 SPARC CPU 203 /leon3 Files specific to Gaisler LEON3 SPARC CPU 204 /lib Architecture specific library files 205 /x86 Files generic to x86 architecture 206 /cpu CPU specific files 207 /lib Architecture specific library files 208/api Machine/arch independent API for external apps 209/board Board dependent files 210/common Misc architecture independent functions 211/disk Code for disk drive partition handling 212/doc Documentation (don't expect too much) 213/drivers Commonly used device drivers 214/dts Contains Makefile for building internal U-Boot fdt. 215/examples Example code for standalone applications, etc. 216/fs Filesystem code (cramfs, ext2, jffs2, etc.) 217/include Header Files 218/lib Files generic to all architectures 219 /libfdt Library files to support flattened device trees 220 /lzma Library files to support LZMA decompression 221 /lzo Library files to support LZO decompression 222/net Networking code 223/post Power On Self Test 224/spl Secondary Program Loader framework 225/tools Tools to build S-Record or U-Boot images, etc. 226 227Software Configuration: 228======================= 229 230Configuration is usually done using C preprocessor defines; the 231rationale behind that is to avoid dead code whenever possible. 232 233There are two classes of configuration variables: 234 235* Configuration _OPTIONS_: 236 These are selectable by the user and have names beginning with 237 "CONFIG_". 238 239* Configuration _SETTINGS_: 240 These depend on the hardware etc. and should not be meddled with if 241 you don't know what you're doing; they have names beginning with 242 "CONFIG_SYS_". 243 244Later we will add a configuration tool - probably similar to or even 245identical to what's used for the Linux kernel. Right now, we have to 246do the configuration by hand, which means creating some symbolic 247links and editing some configuration files. We use the TQM8xxL boards 248as an example here. 249 250 251Selection of Processor Architecture and Board Type: 252--------------------------------------------------- 253 254For all supported boards there are ready-to-use default 255configurations available; just type "make <board_name>_config". 256 257Example: For a TQM823L module type: 258 259 cd u-boot 260 make TQM823L_config 261 262For the Cogent platform, you need to specify the CPU type as well; 263e.g. "make cogent_mpc8xx_config". And also configure the cogent 264directory according to the instructions in cogent/README. 265 266 267Sandbox Environment: 268-------------------- 269 270U-Boot can be built natively to run on a Linux host using the 'sandbox' 271board. This allows feature development which is not board- or architecture- 272specific to be undertaken on a native platform. The sandbox is also used to 273run some of U-Boot's tests. 274 275See board/sandbox/sandbox/README.sandbox for more details. 276 277 278Configuration Options: 279---------------------- 280 281Configuration depends on the combination of board and CPU type; all 282such information is kept in a configuration file 283"include/configs/<board_name>.h". 284 285Example: For a TQM823L module, all configuration settings are in 286"include/configs/TQM823L.h". 287 288 289Many of the options are named exactly as the corresponding Linux 290kernel configuration options. The intention is to make it easier to 291build a config tool - later. 292 293 294The following options need to be configured: 295 296- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 297 298- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 299 300- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 301 Define exactly one, e.g. CONFIG_ATSTK1002 302 303- CPU Module Type: (if CONFIG_COGENT is defined) 304 Define exactly one of 305 CONFIG_CMA286_60_OLD 306--- FIXME --- not tested yet: 307 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 308 CONFIG_CMA287_23, CONFIG_CMA287_50 309 310- Motherboard Type: (if CONFIG_COGENT is defined) 311 Define exactly one of 312 CONFIG_CMA101, CONFIG_CMA102 313 314- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 315 Define one or more of 316 CONFIG_CMA302 317 318- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 319 Define one or more of 320 CONFIG_LCD_HEARTBEAT - update a character position on 321 the LCD display every second with 322 a "rotator" |\-/|\-/ 323 324- Board flavour: (if CONFIG_MPC8260ADS is defined) 325 CONFIG_ADSTYPE 326 Possible values are: 327 CONFIG_SYS_8260ADS - original MPC8260ADS 328 CONFIG_SYS_8266ADS - MPC8266ADS 329 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 330 CONFIG_SYS_8272ADS - MPC8272ADS 331 332- Marvell Family Member 333 CONFIG_SYS_MVFS - define it if you want to enable 334 multiple fs option at one time 335 for marvell soc family 336 337- MPC824X Family Member (if CONFIG_MPC824X is defined) 338 Define exactly one of 339 CONFIG_MPC8240, CONFIG_MPC8245 340 341- 8xx CPU Options: (if using an MPC8xx CPU) 342 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 343 get_gclk_freq() cannot work 344 e.g. if there is no 32KHz 345 reference PIT/RTC clock 346 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 347 or XTAL/EXTAL) 348 349- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 350 CONFIG_SYS_8xx_CPUCLK_MIN 351 CONFIG_SYS_8xx_CPUCLK_MAX 352 CONFIG_8xx_CPUCLK_DEFAULT 353 See doc/README.MPC866 354 355 CONFIG_SYS_MEASURE_CPUCLK 356 357 Define this to measure the actual CPU clock instead 358 of relying on the correctness of the configured 359 values. Mostly useful for board bringup to make sure 360 the PLL is locked at the intended frequency. Note 361 that this requires a (stable) reference clock (32 kHz 362 RTC clock or CONFIG_SYS_8XX_XIN) 363 364 CONFIG_SYS_DELAYED_ICACHE 365 366 Define this option if you want to enable the 367 ICache only when Code runs from RAM. 368 369- 85xx CPU Options: 370 CONFIG_SYS_PPC64 371 372 Specifies that the core is a 64-bit PowerPC implementation (implements 373 the "64" category of the Power ISA). This is necessary for ePAPR 374 compliance, among other possible reasons. 375 376 CONFIG_SYS_FSL_TBCLK_DIV 377 378 Defines the core time base clock divider ratio compared to the 379 system clock. On most PQ3 devices this is 8, on newer QorIQ 380 devices it can be 16 or 32. The ratio varies from SoC to Soc. 381 382 CONFIG_SYS_FSL_PCIE_COMPAT 383 384 Defines the string to utilize when trying to match PCIe device 385 tree nodes for the given platform. 386 387 CONFIG_SYS_PPC_E500_DEBUG_TLB 388 389 Enables a temporary TLB entry to be used during boot to work 390 around limitations in e500v1 and e500v2 external debugger 391 support. This reduces the portions of the boot code where 392 breakpoints and single stepping do not work. The value of this 393 symbol should be set to the TLB1 entry to be used for this 394 purpose. 395 396 CONFIG_SYS_FSL_ERRATUM_A004510 397 398 Enables a workaround for erratum A004510. If set, 399 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 400 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 401 402 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 403 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 404 405 Defines one or two SoC revisions (low 8 bits of SVR) 406 for which the A004510 workaround should be applied. 407 408 The rest of SVR is either not relevant to the decision 409 of whether the erratum is present (e.g. p2040 versus 410 p2041) or is implied by the build target, which controls 411 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 412 413 See Freescale App Note 4493 for more information about 414 this erratum. 415 416 CONFIG_A003399_NOR_WORKAROUND 417 Enables a workaround for IFC erratum A003399. It is only 418 requred during NOR boot. 419 420 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 421 422 This is the value to write into CCSR offset 0x18600 423 according to the A004510 workaround. 424 425 CONFIG_SYS_FSL_DSP_DDR_ADDR 426 This value denotes start offset of DDR memory which is 427 connected exclusively to the DSP cores. 428 429 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 430 This value denotes start offset of M2 memory 431 which is directly connected to the DSP core. 432 433 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 434 This value denotes start offset of M3 memory which is directly 435 connected to the DSP core. 436 437 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 438 This value denotes start offset of DSP CCSR space. 439 440 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 441 Single Source Clock is clocking mode present in some of FSL SoC's. 442 In this mode, a single differential clock is used to supply 443 clocks to the sysclock, ddrclock and usbclock. 444 445 CONFIG_SYS_CPC_REINIT_F 446 This CONFIG is defined when the CPC is configured as SRAM at the 447 time of U-boot entry and is required to be re-initialized. 448 449 CONFIG_DEEP_SLEEP 450 Inidcates this SoC supports deep sleep feature. If deep sleep is 451 supported, core will start to execute uboot when wakes up. 452 453- Generic CPU options: 454 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 455 456 Defines the endianess of the CPU. Implementation of those 457 values is arch specific. 458 459 CONFIG_SYS_FSL_DDR 460 Freescale DDR driver in use. This type of DDR controller is 461 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 462 SoCs. 463 464 CONFIG_SYS_FSL_DDR_ADDR 465 Freescale DDR memory-mapped register base. 466 467 CONFIG_SYS_FSL_DDR_EMU 468 Specify emulator support for DDR. Some DDR features such as 469 deskew training are not available. 470 471 CONFIG_SYS_FSL_DDRC_GEN1 472 Freescale DDR1 controller. 473 474 CONFIG_SYS_FSL_DDRC_GEN2 475 Freescale DDR2 controller. 476 477 CONFIG_SYS_FSL_DDRC_GEN3 478 Freescale DDR3 controller. 479 480 CONFIG_SYS_FSL_DDRC_GEN4 481 Freescale DDR4 controller. 482 483 CONFIG_SYS_FSL_DDRC_ARM_GEN3 484 Freescale DDR3 controller for ARM-based SoCs. 485 486 CONFIG_SYS_FSL_DDR1 487 Board config to use DDR1. It can be enabled for SoCs with 488 Freescale DDR1 or DDR2 controllers, depending on the board 489 implemetation. 490 491 CONFIG_SYS_FSL_DDR2 492 Board config to use DDR2. It can be eanbeld for SoCs with 493 Freescale DDR2 or DDR3 controllers, depending on the board 494 implementation. 495 496 CONFIG_SYS_FSL_DDR3 497 Board config to use DDR3. It can be enabled for SoCs with 498 Freescale DDR3 or DDR3L controllers. 499 500 CONFIG_SYS_FSL_DDR3L 501 Board config to use DDR3L. It can be enabled for SoCs with 502 DDR3L controllers. 503 504 CONFIG_SYS_FSL_DDR4 505 Board config to use DDR4. It can be enabled for SoCs with 506 DDR4 controllers. 507 508 CONFIG_SYS_FSL_IFC_BE 509 Defines the IFC controller register space as Big Endian 510 511 CONFIG_SYS_FSL_IFC_LE 512 Defines the IFC controller register space as Little Endian 513 514 CONFIG_SYS_FSL_PBL_PBI 515 It enables addition of RCW (Power on reset configuration) in built image. 516 Please refer doc/README.pblimage for more details 517 518 CONFIG_SYS_FSL_PBL_RCW 519 It adds PBI(pre-boot instructions) commands in u-boot build image. 520 PBI commands can be used to configure SoC before it starts the execution. 521 Please refer doc/README.pblimage for more details 522 523 CONFIG_SPL_FSL_PBL 524 It adds a target to create boot binary having SPL binary in PBI format 525 concatenated with u-boot binary. 526 527 CONFIG_SYS_FSL_DDR_BE 528 Defines the DDR controller register space as Big Endian 529 530 CONFIG_SYS_FSL_DDR_LE 531 Defines the DDR controller register space as Little Endian 532 533 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 534 Physical address from the view of DDR controllers. It is the 535 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 536 it could be different for ARM SoCs. 537 538 CONFIG_SYS_FSL_DDR_INTLV_256B 539 DDR controller interleaving on 256-byte. This is a special 540 interleaving mode, handled by Dickens for Freescale layerscape 541 SoCs with ARM core. 542 543- Intel Monahans options: 544 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 545 546 Defines the Monahans run mode to oscillator 547 ratio. Valid values are 8, 16, 24, 31. The core 548 frequency is this value multiplied by 13 MHz. 549 550 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 551 552 Defines the Monahans turbo mode to oscillator 553 ratio. Valid values are 1 (default if undefined) and 554 2. The core frequency as calculated above is multiplied 555 by this value. 556 557- MIPS CPU options: 558 CONFIG_SYS_INIT_SP_OFFSET 559 560 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 561 pointer. This is needed for the temporary stack before 562 relocation. 563 564 CONFIG_SYS_MIPS_CACHE_MODE 565 566 Cache operation mode for the MIPS CPU. 567 See also arch/mips/include/asm/mipsregs.h. 568 Possible values are: 569 CONF_CM_CACHABLE_NO_WA 570 CONF_CM_CACHABLE_WA 571 CONF_CM_UNCACHED 572 CONF_CM_CACHABLE_NONCOHERENT 573 CONF_CM_CACHABLE_CE 574 CONF_CM_CACHABLE_COW 575 CONF_CM_CACHABLE_CUW 576 CONF_CM_CACHABLE_ACCELERATED 577 578 CONFIG_SYS_XWAY_EBU_BOOTCFG 579 580 Special option for Lantiq XWAY SoCs for booting from NOR flash. 581 See also arch/mips/cpu/mips32/start.S. 582 583 CONFIG_XWAY_SWAP_BYTES 584 585 Enable compilation of tools/xway-swap-bytes needed for Lantiq 586 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 587 be swapped if a flash programmer is used. 588 589- ARM options: 590 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 591 592 Select high exception vectors of the ARM core, e.g., do not 593 clear the V bit of the c1 register of CP15. 594 595 CONFIG_SYS_THUMB_BUILD 596 597 Use this flag to build U-Boot using the Thumb instruction 598 set for ARM architectures. Thumb instruction set provides 599 better code density. For ARM architectures that support 600 Thumb2 this flag will result in Thumb2 code generated by 601 GCC. 602 603 CONFIG_ARM_ERRATA_716044 604 CONFIG_ARM_ERRATA_742230 605 CONFIG_ARM_ERRATA_743622 606 CONFIG_ARM_ERRATA_751472 607 CONFIG_ARM_ERRATA_794072 608 CONFIG_ARM_ERRATA_761320 609 610 If set, the workarounds for these ARM errata are applied early 611 during U-Boot startup. Note that these options force the 612 workarounds to be applied; no CPU-type/version detection 613 exists, unlike the similar options in the Linux kernel. Do not 614 set these options unless they apply! 615 616- CPU timer options: 617 CONFIG_SYS_HZ 618 619 The frequency of the timer returned by get_timer(). 620 get_timer() must operate in milliseconds and this CONFIG 621 option must be set to 1000. 622 623- Linux Kernel Interface: 624 CONFIG_CLOCKS_IN_MHZ 625 626 U-Boot stores all clock information in Hz 627 internally. For binary compatibility with older Linux 628 kernels (which expect the clocks passed in the 629 bd_info data to be in MHz) the environment variable 630 "clocks_in_mhz" can be defined so that U-Boot 631 converts clock data to MHZ before passing it to the 632 Linux kernel. 633 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 634 "clocks_in_mhz=1" is automatically included in the 635 default environment. 636 637 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 638 639 When transferring memsize parameter to linux, some versions 640 expect it to be in bytes, others in MB. 641 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 642 643 CONFIG_OF_LIBFDT 644 645 New kernel versions are expecting firmware settings to be 646 passed using flattened device trees (based on open firmware 647 concepts). 648 649 CONFIG_OF_LIBFDT 650 * New libfdt-based support 651 * Adds the "fdt" command 652 * The bootm command automatically updates the fdt 653 654 OF_CPU - The proper name of the cpus node (only required for 655 MPC512X and MPC5xxx based boards). 656 OF_SOC - The proper name of the soc node (only required for 657 MPC512X and MPC5xxx based boards). 658 OF_TBCLK - The timebase frequency. 659 OF_STDOUT_PATH - The path to the console device 660 661 boards with QUICC Engines require OF_QE to set UCC MAC 662 addresses 663 664 CONFIG_OF_BOARD_SETUP 665 666 Board code has addition modification that it wants to make 667 to the flat device tree before handing it off to the kernel 668 669 CONFIG_OF_BOOT_CPU 670 671 This define fills in the correct boot CPU in the boot 672 param header, the default value is zero if undefined. 673 674 CONFIG_OF_IDE_FIXUP 675 676 U-Boot can detect if an IDE device is present or not. 677 If not, and this new config option is activated, U-Boot 678 removes the ATA node from the DTS before booting Linux, 679 so the Linux IDE driver does not probe the device and 680 crash. This is needed for buggy hardware (uc101) where 681 no pull down resistor is connected to the signal IDE5V_DD7. 682 683 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 684 685 This setting is mandatory for all boards that have only one 686 machine type and must be used to specify the machine type 687 number as it appears in the ARM machine registry 688 (see http://www.arm.linux.org.uk/developer/machines/). 689 Only boards that have multiple machine types supported 690 in a single configuration file and the machine type is 691 runtime discoverable, do not have to use this setting. 692 693- vxWorks boot parameters: 694 695 bootvx constructs a valid bootline using the following 696 environments variables: bootfile, ipaddr, serverip, hostname. 697 It loads the vxWorks image pointed bootfile. 698 699 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 700 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 701 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 702 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 703 704 CONFIG_SYS_VXWORKS_ADD_PARAMS 705 706 Add it at the end of the bootline. E.g "u=username pw=secret" 707 708 Note: If a "bootargs" environment is defined, it will overwride 709 the defaults discussed just above. 710 711- Cache Configuration: 712 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 713 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 714 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 715 716- Cache Configuration for ARM: 717 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 718 controller 719 CONFIG_SYS_PL310_BASE - Physical base address of PL310 720 controller register space 721 722- Serial Ports: 723 CONFIG_PL010_SERIAL 724 725 Define this if you want support for Amba PrimeCell PL010 UARTs. 726 727 CONFIG_PL011_SERIAL 728 729 Define this if you want support for Amba PrimeCell PL011 UARTs. 730 731 CONFIG_PL011_CLOCK 732 733 If you have Amba PrimeCell PL011 UARTs, set this variable to 734 the clock speed of the UARTs. 735 736 CONFIG_PL01x_PORTS 737 738 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 739 define this to a list of base addresses for each (supported) 740 port. See e.g. include/configs/versatile.h 741 742 CONFIG_PL011_SERIAL_RLCR 743 744 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 745 have separate receive and transmit line control registers. Set 746 this variable to initialize the extra register. 747 748 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 749 750 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 751 boot loader that has already initialized the UART. Define this 752 variable to flush the UART at init time. 753 754 755- Console Interface: 756 Depending on board, define exactly one serial port 757 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 758 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 759 console by defining CONFIG_8xx_CONS_NONE 760 761 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 762 port routines must be defined elsewhere 763 (i.e. serial_init(), serial_getc(), ...) 764 765 CONFIG_CFB_CONSOLE 766 Enables console device for a color framebuffer. Needs following 767 defines (cf. smiLynxEM, i8042) 768 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 769 (default big endian) 770 VIDEO_HW_RECTFILL graphic chip supports 771 rectangle fill 772 (cf. smiLynxEM) 773 VIDEO_HW_BITBLT graphic chip supports 774 bit-blit (cf. smiLynxEM) 775 VIDEO_VISIBLE_COLS visible pixel columns 776 (cols=pitch) 777 VIDEO_VISIBLE_ROWS visible pixel rows 778 VIDEO_PIXEL_SIZE bytes per pixel 779 VIDEO_DATA_FORMAT graphic data format 780 (0-5, cf. cfb_console.c) 781 VIDEO_FB_ADRS framebuffer address 782 VIDEO_KBD_INIT_FCT keyboard int fct 783 (i.e. i8042_kbd_init()) 784 VIDEO_TSTC_FCT test char fct 785 (i.e. i8042_tstc) 786 VIDEO_GETC_FCT get char fct 787 (i.e. i8042_getc) 788 CONFIG_CONSOLE_CURSOR cursor drawing on/off 789 (requires blink timer 790 cf. i8042.c) 791 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 792 CONFIG_CONSOLE_TIME display time/date info in 793 upper right corner 794 (requires CONFIG_CMD_DATE) 795 CONFIG_VIDEO_LOGO display Linux logo in 796 upper left corner 797 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 798 linux_logo.h for logo. 799 Requires CONFIG_VIDEO_LOGO 800 CONFIG_CONSOLE_EXTRA_INFO 801 additional board info beside 802 the logo 803 804 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 805 a limited number of ANSI escape sequences (cursor control, 806 erase functions and limited graphics rendition control). 807 808 When CONFIG_CFB_CONSOLE is defined, video console is 809 default i/o. Serial console can be forced with 810 environment 'console=serial'. 811 812 When CONFIG_SILENT_CONSOLE is defined, all console 813 messages (by U-Boot and Linux!) can be silenced with 814 the "silent" environment variable. See 815 doc/README.silent for more information. 816 817 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 818 is 0x00. 819 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 820 is 0xa0. 821 822- Console Baudrate: 823 CONFIG_BAUDRATE - in bps 824 Select one of the baudrates listed in 825 CONFIG_SYS_BAUDRATE_TABLE, see below. 826 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 827 828- Console Rx buffer length 829 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 830 the maximum receive buffer length for the SMC. 831 This option is actual only for 82xx and 8xx possible. 832 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 833 must be defined, to setup the maximum idle timeout for 834 the SMC. 835 836- Pre-Console Buffer: 837 Prior to the console being initialised (i.e. serial UART 838 initialised etc) all console output is silently discarded. 839 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 840 buffer any console messages prior to the console being 841 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 842 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 843 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 844 bytes are output before the console is initialised, the 845 earlier bytes are discarded. 846 847 'Sane' compilers will generate smaller code if 848 CONFIG_PRE_CON_BUF_SZ is a power of 2 849 850- Safe printf() functions 851 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 852 the printf() functions. These are defined in 853 include/vsprintf.h and include snprintf(), vsnprintf() and 854 so on. Code size increase is approximately 300-500 bytes. 855 If this option is not given then these functions will 856 silently discard their buffer size argument - this means 857 you are not getting any overflow checking in this case. 858 859- Boot Delay: CONFIG_BOOTDELAY - in seconds 860 Delay before automatically booting the default image; 861 set to -1 to disable autoboot. 862 set to -2 to autoboot with no delay and not check for abort 863 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 864 865 See doc/README.autoboot for these options that 866 work with CONFIG_BOOTDELAY. None are required. 867 CONFIG_BOOT_RETRY_TIME 868 CONFIG_BOOT_RETRY_MIN 869 CONFIG_AUTOBOOT_KEYED 870 CONFIG_AUTOBOOT_PROMPT 871 CONFIG_AUTOBOOT_DELAY_STR 872 CONFIG_AUTOBOOT_STOP_STR 873 CONFIG_AUTOBOOT_DELAY_STR2 874 CONFIG_AUTOBOOT_STOP_STR2 875 CONFIG_ZERO_BOOTDELAY_CHECK 876 CONFIG_RESET_TO_RETRY 877 878- Autoboot Command: 879 CONFIG_BOOTCOMMAND 880 Only needed when CONFIG_BOOTDELAY is enabled; 881 define a command string that is automatically executed 882 when no character is read on the console interface 883 within "Boot Delay" after reset. 884 885 CONFIG_BOOTARGS 886 This can be used to pass arguments to the bootm 887 command. The value of CONFIG_BOOTARGS goes into the 888 environment value "bootargs". 889 890 CONFIG_RAMBOOT and CONFIG_NFSBOOT 891 The value of these goes into the environment as 892 "ramboot" and "nfsboot" respectively, and can be used 893 as a convenience, when switching between booting from 894 RAM and NFS. 895 896- Bootcount: 897 CONFIG_BOOTCOUNT_LIMIT 898 Implements a mechanism for detecting a repeating reboot 899 cycle, see: 900 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 901 902 CONFIG_BOOTCOUNT_ENV 903 If no softreset save registers are found on the hardware 904 "bootcount" is stored in the environment. To prevent a 905 saveenv on all reboots, the environment variable 906 "upgrade_available" is used. If "upgrade_available" is 907 0, "bootcount" is always 0, if "upgrade_available" is 908 1 "bootcount" is incremented in the environment. 909 So the Userspace Applikation must set the "upgrade_available" 910 and "bootcount" variable to 0, if a boot was successfully. 911 912- Pre-Boot Commands: 913 CONFIG_PREBOOT 914 915 When this option is #defined, the existence of the 916 environment variable "preboot" will be checked 917 immediately before starting the CONFIG_BOOTDELAY 918 countdown and/or running the auto-boot command resp. 919 entering interactive mode. 920 921 This feature is especially useful when "preboot" is 922 automatically generated or modified. For an example 923 see the LWMON board specific code: here "preboot" is 924 modified when the user holds down a certain 925 combination of keys on the (special) keyboard when 926 booting the systems 927 928- Serial Download Echo Mode: 929 CONFIG_LOADS_ECHO 930 If defined to 1, all characters received during a 931 serial download (using the "loads" command) are 932 echoed back. This might be needed by some terminal 933 emulations (like "cu"), but may as well just take 934 time on others. This setting #define's the initial 935 value of the "loads_echo" environment variable. 936 937- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 938 CONFIG_KGDB_BAUDRATE 939 Select one of the baudrates listed in 940 CONFIG_SYS_BAUDRATE_TABLE, see below. 941 942- Monitor Functions: 943 Monitor commands can be included or excluded 944 from the build by using the #include files 945 <config_cmd_all.h> and #undef'ing unwanted 946 commands, or using <config_cmd_default.h> 947 and augmenting with additional #define's 948 for wanted commands. 949 950 The default command configuration includes all commands 951 except those marked below with a "*". 952 953 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 954 CONFIG_CMD_ASKENV * ask for env variable 955 CONFIG_CMD_BDI bdinfo 956 CONFIG_CMD_BEDBUG * Include BedBug Debugger 957 CONFIG_CMD_BMP * BMP support 958 CONFIG_CMD_BSP * Board specific commands 959 CONFIG_CMD_BOOTD bootd 960 CONFIG_CMD_CACHE * icache, dcache 961 CONFIG_CMD_CLK * clock command support 962 CONFIG_CMD_CONSOLE coninfo 963 CONFIG_CMD_CRC32 * crc32 964 CONFIG_CMD_DATE * support for RTC, date/time... 965 CONFIG_CMD_DHCP * DHCP support 966 CONFIG_CMD_DIAG * Diagnostics 967 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 968 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 969 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 970 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 971 CONFIG_CMD_DTT * Digital Therm and Thermostat 972 CONFIG_CMD_ECHO echo arguments 973 CONFIG_CMD_EDITENV edit env variable 974 CONFIG_CMD_EEPROM * EEPROM read/write support 975 CONFIG_CMD_ELF * bootelf, bootvx 976 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 977 CONFIG_CMD_ENV_FLAGS * display details about env flags 978 CONFIG_CMD_ENV_EXISTS * check existence of env variable 979 CONFIG_CMD_EXPORTENV * export the environment 980 CONFIG_CMD_EXT2 * ext2 command support 981 CONFIG_CMD_EXT4 * ext4 command support 982 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 983 that work for multiple fs types 984 CONFIG_CMD_SAVEENV saveenv 985 CONFIG_CMD_FDC * Floppy Disk Support 986 CONFIG_CMD_FAT * FAT command support 987 CONFIG_CMD_FLASH flinfo, erase, protect 988 CONFIG_CMD_FPGA FPGA device initialization support 989 CONFIG_CMD_FUSE * Device fuse support 990 CONFIG_CMD_GETTIME * Get time since boot 991 CONFIG_CMD_GO * the 'go' command (exec code) 992 CONFIG_CMD_GREPENV * search environment 993 CONFIG_CMD_HASH * calculate hash / digest 994 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 995 CONFIG_CMD_I2C * I2C serial bus support 996 CONFIG_CMD_IDE * IDE harddisk support 997 CONFIG_CMD_IMI iminfo 998 CONFIG_CMD_IMLS List all images found in NOR flash 999 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1000 CONFIG_CMD_IMMAP * IMMR dump support 1001 CONFIG_CMD_IMPORTENV * import an environment 1002 CONFIG_CMD_INI * import data from an ini file into the env 1003 CONFIG_CMD_IRQ * irqinfo 1004 CONFIG_CMD_ITEST Integer/string test of 2 values 1005 CONFIG_CMD_JFFS2 * JFFS2 Support 1006 CONFIG_CMD_KGDB * kgdb 1007 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1008 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1009 (169.254.*.*) 1010 CONFIG_CMD_LOADB loadb 1011 CONFIG_CMD_LOADS loads 1012 CONFIG_CMD_MD5SUM * print md5 message digest 1013 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1014 CONFIG_CMD_MEMINFO * Display detailed memory information 1015 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1016 loop, loopw 1017 CONFIG_CMD_MEMTEST * mtest 1018 CONFIG_CMD_MISC Misc functions like sleep etc 1019 CONFIG_CMD_MMC * MMC memory mapped support 1020 CONFIG_CMD_MII * MII utility commands 1021 CONFIG_CMD_MTDPARTS * MTD partition support 1022 CONFIG_CMD_NAND * NAND support 1023 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1024 CONFIG_CMD_NFS NFS support 1025 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1026 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1027 CONFIG_CMD_PCI * pciinfo 1028 CONFIG_CMD_PCMCIA * PCMCIA support 1029 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1030 host 1031 CONFIG_CMD_PORTIO * Port I/O 1032 CONFIG_CMD_READ * Read raw data from partition 1033 CONFIG_CMD_REGINFO * Register dump 1034 CONFIG_CMD_RUN run command in env variable 1035 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1036 CONFIG_CMD_SAVES * save S record dump 1037 CONFIG_CMD_SCSI * SCSI Support 1038 CONFIG_CMD_SDRAM * print SDRAM configuration information 1039 (requires CONFIG_CMD_I2C) 1040 CONFIG_CMD_SETGETDCR Support for DCR Register access 1041 (4xx only) 1042 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1043 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1044 (requires CONFIG_CMD_MEMORY) 1045 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1046 CONFIG_CMD_SOURCE "source" command Support 1047 CONFIG_CMD_SPI * SPI serial bus support 1048 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1049 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1050 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1051 CONFIG_CMD_TIMER * access to the system tick timer 1052 CONFIG_CMD_USB * USB support 1053 CONFIG_CMD_CDP * Cisco Discover Protocol support 1054 CONFIG_CMD_MFSL * Microblaze FSL support 1055 CONFIG_CMD_XIMG Load part of Multi Image 1056 CONFIG_CMD_UUID * Generate random UUID or GUID string 1057 1058 EXAMPLE: If you want all functions except of network 1059 support you can write: 1060 1061 #include "config_cmd_all.h" 1062 #undef CONFIG_CMD_NET 1063 1064 Other Commands: 1065 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1066 1067 Note: Don't enable the "icache" and "dcache" commands 1068 (configuration option CONFIG_CMD_CACHE) unless you know 1069 what you (and your U-Boot users) are doing. Data 1070 cache cannot be enabled on systems like the 8xx or 1071 8260 (where accesses to the IMMR region must be 1072 uncached), and it cannot be disabled on all other 1073 systems where we (mis-) use the data cache to hold an 1074 initial stack and some data. 1075 1076 1077 XXX - this list needs to get updated! 1078 1079- Regular expression support: 1080 CONFIG_REGEX 1081 If this variable is defined, U-Boot is linked against 1082 the SLRE (Super Light Regular Expression) library, 1083 which adds regex support to some commands, as for 1084 example "env grep" and "setexpr". 1085 1086- Device tree: 1087 CONFIG_OF_CONTROL 1088 If this variable is defined, U-Boot will use a device tree 1089 to configure its devices, instead of relying on statically 1090 compiled #defines in the board file. This option is 1091 experimental and only available on a few boards. The device 1092 tree is available in the global data as gd->fdt_blob. 1093 1094 U-Boot needs to get its device tree from somewhere. This can 1095 be done using one of the two options below: 1096 1097 CONFIG_OF_EMBED 1098 If this variable is defined, U-Boot will embed a device tree 1099 binary in its image. This device tree file should be in the 1100 board directory and called <soc>-<board>.dts. The binary file 1101 is then picked up in board_init_f() and made available through 1102 the global data structure as gd->blob. 1103 1104 CONFIG_OF_SEPARATE 1105 If this variable is defined, U-Boot will build a device tree 1106 binary. It will be called u-boot.dtb. Architecture-specific 1107 code will locate it at run-time. Generally this works by: 1108 1109 cat u-boot.bin u-boot.dtb >image.bin 1110 1111 and in fact, U-Boot does this for you, creating a file called 1112 u-boot-dtb.bin which is useful in the common case. You can 1113 still use the individual files if you need something more 1114 exotic. 1115 1116- Watchdog: 1117 CONFIG_WATCHDOG 1118 If this variable is defined, it enables watchdog 1119 support for the SoC. There must be support in the SoC 1120 specific code for a watchdog. For the 8xx and 8260 1121 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1122 register. When supported for a specific SoC is 1123 available, then no further board specific code should 1124 be needed to use it. 1125 1126 CONFIG_HW_WATCHDOG 1127 When using a watchdog circuitry external to the used 1128 SoC, then define this variable and provide board 1129 specific code for the "hw_watchdog_reset" function. 1130 1131- U-Boot Version: 1132 CONFIG_VERSION_VARIABLE 1133 If this variable is defined, an environment variable 1134 named "ver" is created by U-Boot showing the U-Boot 1135 version as printed by the "version" command. 1136 Any change to this variable will be reverted at the 1137 next reset. 1138 1139- Real-Time Clock: 1140 1141 When CONFIG_CMD_DATE is selected, the type of the RTC 1142 has to be selected, too. Define exactly one of the 1143 following options: 1144 1145 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1146 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1147 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1148 CONFIG_RTC_MC146818 - use MC146818 RTC 1149 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1150 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1151 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1152 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1153 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1154 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1155 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1156 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1157 RV3029 RTC. 1158 1159 Note that if the RTC uses I2C, then the I2C interface 1160 must also be configured. See I2C Support, below. 1161 1162- GPIO Support: 1163 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1164 1165 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1166 chip-ngpio pairs that tell the PCA953X driver the number of 1167 pins supported by a particular chip. 1168 1169 Note that if the GPIO device uses I2C, then the I2C interface 1170 must also be configured. See I2C Support, below. 1171 1172- Timestamp Support: 1173 1174 When CONFIG_TIMESTAMP is selected, the timestamp 1175 (date and time) of an image is printed by image 1176 commands like bootm or iminfo. This option is 1177 automatically enabled when you select CONFIG_CMD_DATE . 1178 1179- Partition Labels (disklabels) Supported: 1180 Zero or more of the following: 1181 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1182 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1183 Intel architecture, USB sticks, etc. 1184 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1185 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1186 bootloader. Note 2TB partition limit; see 1187 disk/part_efi.c 1188 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1189 1190 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1191 CONFIG_CMD_SCSI) you must configure support for at 1192 least one non-MTD partition type as well. 1193 1194- IDE Reset method: 1195 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1196 board configurations files but used nowhere! 1197 1198 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1199 be performed by calling the function 1200 ide_set_reset(int reset) 1201 which has to be defined in a board specific file 1202 1203- ATAPI Support: 1204 CONFIG_ATAPI 1205 1206 Set this to enable ATAPI support. 1207 1208- LBA48 Support 1209 CONFIG_LBA48 1210 1211 Set this to enable support for disks larger than 137GB 1212 Also look at CONFIG_SYS_64BIT_LBA. 1213 Whithout these , LBA48 support uses 32bit variables and will 'only' 1214 support disks up to 2.1TB. 1215 1216 CONFIG_SYS_64BIT_LBA: 1217 When enabled, makes the IDE subsystem use 64bit sector addresses. 1218 Default is 32bit. 1219 1220- SCSI Support: 1221 At the moment only there is only support for the 1222 SYM53C8XX SCSI controller; define 1223 CONFIG_SCSI_SYM53C8XX to enable it. 1224 1225 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1226 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1227 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1228 maximum numbers of LUNs, SCSI ID's and target 1229 devices. 1230 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1231 1232 The environment variable 'scsidevs' is set to the number of 1233 SCSI devices found during the last scan. 1234 1235- NETWORK Support (PCI): 1236 CONFIG_E1000 1237 Support for Intel 8254x/8257x gigabit chips. 1238 1239 CONFIG_E1000_SPI 1240 Utility code for direct access to the SPI bus on Intel 8257x. 1241 This does not do anything useful unless you set at least one 1242 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1243 1244 CONFIG_E1000_SPI_GENERIC 1245 Allow generic access to the SPI bus on the Intel 8257x, for 1246 example with the "sspi" command. 1247 1248 CONFIG_CMD_E1000 1249 Management command for E1000 devices. When used on devices 1250 with SPI support you can reprogram the EEPROM from U-Boot. 1251 1252 CONFIG_E1000_FALLBACK_MAC 1253 default MAC for empty EEPROM after production. 1254 1255 CONFIG_EEPRO100 1256 Support for Intel 82557/82559/82559ER chips. 1257 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1258 write routine for first time initialisation. 1259 1260 CONFIG_TULIP 1261 Support for Digital 2114x chips. 1262 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1263 modem chip initialisation (KS8761/QS6611). 1264 1265 CONFIG_NATSEMI 1266 Support for National dp83815 chips. 1267 1268 CONFIG_NS8382X 1269 Support for National dp8382[01] gigabit chips. 1270 1271- NETWORK Support (other): 1272 1273 CONFIG_DRIVER_AT91EMAC 1274 Support for AT91RM9200 EMAC. 1275 1276 CONFIG_RMII 1277 Define this to use reduced MII inteface 1278 1279 CONFIG_DRIVER_AT91EMAC_QUIET 1280 If this defined, the driver is quiet. 1281 The driver doen't show link status messages. 1282 1283 CONFIG_CALXEDA_XGMAC 1284 Support for the Calxeda XGMAC device 1285 1286 CONFIG_LAN91C96 1287 Support for SMSC's LAN91C96 chips. 1288 1289 CONFIG_LAN91C96_BASE 1290 Define this to hold the physical address 1291 of the LAN91C96's I/O space 1292 1293 CONFIG_LAN91C96_USE_32_BIT 1294 Define this to enable 32 bit addressing 1295 1296 CONFIG_SMC91111 1297 Support for SMSC's LAN91C111 chip 1298 1299 CONFIG_SMC91111_BASE 1300 Define this to hold the physical address 1301 of the device (I/O space) 1302 1303 CONFIG_SMC_USE_32_BIT 1304 Define this if data bus is 32 bits 1305 1306 CONFIG_SMC_USE_IOFUNCS 1307 Define this to use i/o functions instead of macros 1308 (some hardware wont work with macros) 1309 1310 CONFIG_DRIVER_TI_EMAC 1311 Support for davinci emac 1312 1313 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1314 Define this if you have more then 3 PHYs. 1315 1316 CONFIG_FTGMAC100 1317 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1318 1319 CONFIG_FTGMAC100_EGIGA 1320 Define this to use GE link update with gigabit PHY. 1321 Define this if FTGMAC100 is connected to gigabit PHY. 1322 If your system has 10/100 PHY only, it might not occur 1323 wrong behavior. Because PHY usually return timeout or 1324 useless data when polling gigabit status and gigabit 1325 control registers. This behavior won't affect the 1326 correctnessof 10/100 link speed update. 1327 1328 CONFIG_SMC911X 1329 Support for SMSC's LAN911x and LAN921x chips 1330 1331 CONFIG_SMC911X_BASE 1332 Define this to hold the physical address 1333 of the device (I/O space) 1334 1335 CONFIG_SMC911X_32_BIT 1336 Define this if data bus is 32 bits 1337 1338 CONFIG_SMC911X_16_BIT 1339 Define this if data bus is 16 bits. If your processor 1340 automatically converts one 32 bit word to two 16 bit 1341 words you may also try CONFIG_SMC911X_32_BIT. 1342 1343 CONFIG_SH_ETHER 1344 Support for Renesas on-chip Ethernet controller 1345 1346 CONFIG_SH_ETHER_USE_PORT 1347 Define the number of ports to be used 1348 1349 CONFIG_SH_ETHER_PHY_ADDR 1350 Define the ETH PHY's address 1351 1352 CONFIG_SH_ETHER_CACHE_WRITEBACK 1353 If this option is set, the driver enables cache flush. 1354 1355- TPM Support: 1356 CONFIG_TPM 1357 Support TPM devices. 1358 1359 CONFIG_TPM_TIS_I2C 1360 Support for i2c bus TPM devices. Only one device 1361 per system is supported at this time. 1362 1363 CONFIG_TPM_TIS_I2C_BUS_NUMBER 1364 Define the the i2c bus number for the TPM device 1365 1366 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS 1367 Define the TPM's address on the i2c bus 1368 1369 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1370 Define the burst count bytes upper limit 1371 1372 CONFIG_TPM_ATMEL_TWI 1373 Support for Atmel TWI TPM device. Requires I2C support. 1374 1375 CONFIG_TPM_TIS_LPC 1376 Support for generic parallel port TPM devices. Only one device 1377 per system is supported at this time. 1378 1379 CONFIG_TPM_TIS_BASE_ADDRESS 1380 Base address where the generic TPM device is mapped 1381 to. Contemporary x86 systems usually map it at 1382 0xfed40000. 1383 1384 CONFIG_CMD_TPM 1385 Add tpm monitor functions. 1386 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1387 provides monitor access to authorized functions. 1388 1389 CONFIG_TPM 1390 Define this to enable the TPM support library which provides 1391 functional interfaces to some TPM commands. 1392 Requires support for a TPM device. 1393 1394 CONFIG_TPM_AUTH_SESSIONS 1395 Define this to enable authorized functions in the TPM library. 1396 Requires CONFIG_TPM and CONFIG_SHA1. 1397 1398- USB Support: 1399 At the moment only the UHCI host controller is 1400 supported (PIP405, MIP405, MPC5200); define 1401 CONFIG_USB_UHCI to enable it. 1402 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1403 and define CONFIG_USB_STORAGE to enable the USB 1404 storage devices. 1405 Note: 1406 Supported are USB Keyboards and USB Floppy drives 1407 (TEAC FD-05PUB). 1408 MPC5200 USB requires additional defines: 1409 CONFIG_USB_CLOCK 1410 for 528 MHz Clock: 0x0001bbbb 1411 CONFIG_PSC3_USB 1412 for USB on PSC3 1413 CONFIG_USB_CONFIG 1414 for differential drivers: 0x00001000 1415 for single ended drivers: 0x00005000 1416 for differential drivers on PSC3: 0x00000100 1417 for single ended drivers on PSC3: 0x00004100 1418 CONFIG_SYS_USB_EVENT_POLL 1419 May be defined to allow interrupt polling 1420 instead of using asynchronous interrupts 1421 1422 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1423 txfilltuning field in the EHCI controller on reset. 1424 1425 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum 1426 interval for usb hub power-on delay.(minimum 100msec) 1427 1428- USB Device: 1429 Define the below if you wish to use the USB console. 1430 Once firmware is rebuilt from a serial console issue the 1431 command "setenv stdin usbtty; setenv stdout usbtty" and 1432 attach your USB cable. The Unix command "dmesg" should print 1433 it has found a new device. The environment variable usbtty 1434 can be set to gserial or cdc_acm to enable your device to 1435 appear to a USB host as a Linux gserial device or a 1436 Common Device Class Abstract Control Model serial device. 1437 If you select usbtty = gserial you should be able to enumerate 1438 a Linux host by 1439 # modprobe usbserial vendor=0xVendorID product=0xProductID 1440 else if using cdc_acm, simply setting the environment 1441 variable usbtty to be cdc_acm should suffice. The following 1442 might be defined in YourBoardName.h 1443 1444 CONFIG_USB_DEVICE 1445 Define this to build a UDC device 1446 1447 CONFIG_USB_TTY 1448 Define this to have a tty type of device available to 1449 talk to the UDC device 1450 1451 CONFIG_USBD_HS 1452 Define this to enable the high speed support for usb 1453 device and usbtty. If this feature is enabled, a routine 1454 int is_usbd_high_speed(void) 1455 also needs to be defined by the driver to dynamically poll 1456 whether the enumeration has succeded at high speed or full 1457 speed. 1458 1459 CONFIG_SYS_CONSOLE_IS_IN_ENV 1460 Define this if you want stdin, stdout &/or stderr to 1461 be set to usbtty. 1462 1463 mpc8xx: 1464 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1465 Derive USB clock from external clock "blah" 1466 - CONFIG_SYS_USB_EXTC_CLK 0x02 1467 1468 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1469 Derive USB clock from brgclk 1470 - CONFIG_SYS_USB_BRG_CLK 0x04 1471 1472 If you have a USB-IF assigned VendorID then you may wish to 1473 define your own vendor specific values either in BoardName.h 1474 or directly in usbd_vendor_info.h. If you don't define 1475 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1476 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1477 should pretend to be a Linux device to it's target host. 1478 1479 CONFIG_USBD_MANUFACTURER 1480 Define this string as the name of your company for 1481 - CONFIG_USBD_MANUFACTURER "my company" 1482 1483 CONFIG_USBD_PRODUCT_NAME 1484 Define this string as the name of your product 1485 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1486 1487 CONFIG_USBD_VENDORID 1488 Define this as your assigned Vendor ID from the USB 1489 Implementors Forum. This *must* be a genuine Vendor ID 1490 to avoid polluting the USB namespace. 1491 - CONFIG_USBD_VENDORID 0xFFFF 1492 1493 CONFIG_USBD_PRODUCTID 1494 Define this as the unique Product ID 1495 for your device 1496 - CONFIG_USBD_PRODUCTID 0xFFFF 1497 1498- ULPI Layer Support: 1499 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1500 the generic ULPI layer. The generic layer accesses the ULPI PHY 1501 via the platform viewport, so you need both the genric layer and 1502 the viewport enabled. Currently only Chipidea/ARC based 1503 viewport is supported. 1504 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1505 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1506 If your ULPI phy needs a different reference clock than the 1507 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1508 the appropriate value in Hz. 1509 1510- MMC Support: 1511 The MMC controller on the Intel PXA is supported. To 1512 enable this define CONFIG_MMC. The MMC can be 1513 accessed from the boot prompt by mapping the device 1514 to physical memory similar to flash. Command line is 1515 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1516 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1517 1518 CONFIG_SH_MMCIF 1519 Support for Renesas on-chip MMCIF controller 1520 1521 CONFIG_SH_MMCIF_ADDR 1522 Define the base address of MMCIF registers 1523 1524 CONFIG_SH_MMCIF_CLK 1525 Define the clock frequency for MMCIF 1526 1527- USB Device Firmware Update (DFU) class support: 1528 CONFIG_DFU_FUNCTION 1529 This enables the USB portion of the DFU USB class 1530 1531 CONFIG_CMD_DFU 1532 This enables the command "dfu" which is used to have 1533 U-Boot create a DFU class device via USB. This command 1534 requires that the "dfu_alt_info" environment variable be 1535 set and define the alt settings to expose to the host. 1536 1537 CONFIG_DFU_MMC 1538 This enables support for exposing (e)MMC devices via DFU. 1539 1540 CONFIG_DFU_NAND 1541 This enables support for exposing NAND devices via DFU. 1542 1543 CONFIG_DFU_RAM 1544 This enables support for exposing RAM via DFU. 1545 Note: DFU spec refer to non-volatile memory usage, but 1546 allow usages beyond the scope of spec - here RAM usage, 1547 one that would help mostly the developer. 1548 1549 CONFIG_SYS_DFU_DATA_BUF_SIZE 1550 Dfu transfer uses a buffer before writing data to the 1551 raw storage device. Make the size (in bytes) of this buffer 1552 configurable. The size of this buffer is also configurable 1553 through the "dfu_bufsiz" environment variable. 1554 1555 CONFIG_SYS_DFU_MAX_FILE_SIZE 1556 When updating files rather than the raw storage device, 1557 we use a static buffer to copy the file into and then write 1558 the buffer once we've been given the whole file. Define 1559 this to the maximum filesize (in bytes) for the buffer. 1560 Default is 4 MiB if undefined. 1561 1562 DFU_DEFAULT_POLL_TIMEOUT 1563 Poll timeout [ms], is the timeout a device can send to the 1564 host. The host must wait for this timeout before sending 1565 a subsequent DFU_GET_STATUS request to the device. 1566 1567 DFU_MANIFEST_POLL_TIMEOUT 1568 Poll timeout [ms], which the device sends to the host when 1569 entering dfuMANIFEST state. Host waits this timeout, before 1570 sending again an USB request to the device. 1571 1572- Journaling Flash filesystem support: 1573 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1574 CONFIG_JFFS2_NAND_DEV 1575 Define these for a default partition on a NAND device 1576 1577 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1578 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1579 Define these for a default partition on a NOR device 1580 1581 CONFIG_SYS_JFFS_CUSTOM_PART 1582 Define this to create an own partition. You have to provide a 1583 function struct part_info* jffs2_part_info(int part_num) 1584 1585 If you define only one JFFS2 partition you may also want to 1586 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1587 to disable the command chpart. This is the default when you 1588 have not defined a custom partition 1589 1590- FAT(File Allocation Table) filesystem write function support: 1591 CONFIG_FAT_WRITE 1592 1593 Define this to enable support for saving memory data as a 1594 file in FAT formatted partition. 1595 1596 This will also enable the command "fatwrite" enabling the 1597 user to write files to FAT. 1598 1599CBFS (Coreboot Filesystem) support 1600 CONFIG_CMD_CBFS 1601 1602 Define this to enable support for reading from a Coreboot 1603 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1604 and cbfsload. 1605 1606- Keyboard Support: 1607 CONFIG_ISA_KEYBOARD 1608 1609 Define this to enable standard (PC-Style) keyboard 1610 support 1611 1612 CONFIG_I8042_KBD 1613 Standard PC keyboard driver with US (is default) and 1614 GERMAN key layout (switch via environment 'keymap=de') support. 1615 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1616 for cfb_console. Supports cursor blinking. 1617 1618 CONFIG_CROS_EC_KEYB 1619 Enables a Chrome OS keyboard using the CROS_EC interface. 1620 This uses CROS_EC to communicate with a second microcontroller 1621 which provides key scans on request. 1622 1623- Video support: 1624 CONFIG_VIDEO 1625 1626 Define this to enable video support (for output to 1627 video). 1628 1629 CONFIG_VIDEO_CT69000 1630 1631 Enable Chips & Technologies 69000 Video chip 1632 1633 CONFIG_VIDEO_SMI_LYNXEM 1634 Enable Silicon Motion SMI 712/710/810 Video chip. The 1635 video output is selected via environment 'videoout' 1636 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1637 assumed. 1638 1639 For the CT69000 and SMI_LYNXEM drivers, videomode is 1640 selected via environment 'videomode'. Two different ways 1641 are possible: 1642 - "videomode=num" 'num' is a standard LiLo mode numbers. 1643 Following standard modes are supported (* is default): 1644 1645 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1646 -------------+--------------------------------------------- 1647 8 bits | 0x301* 0x303 0x305 0x161 0x307 1648 15 bits | 0x310 0x313 0x316 0x162 0x319 1649 16 bits | 0x311 0x314 0x317 0x163 0x31A 1650 24 bits | 0x312 0x315 0x318 ? 0x31B 1651 -------------+--------------------------------------------- 1652 (i.e. setenv videomode 317; saveenv; reset;) 1653 1654 - "videomode=bootargs" all the video parameters are parsed 1655 from the bootargs. (See drivers/video/videomodes.c) 1656 1657 1658 CONFIG_VIDEO_SED13806 1659 Enable Epson SED13806 driver. This driver supports 8bpp 1660 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1661 or CONFIG_VIDEO_SED13806_16BPP 1662 1663 CONFIG_FSL_DIU_FB 1664 Enable the Freescale DIU video driver. Reference boards for 1665 SOCs that have a DIU should define this macro to enable DIU 1666 support, and should also define these other macros: 1667 1668 CONFIG_SYS_DIU_ADDR 1669 CONFIG_VIDEO 1670 CONFIG_CMD_BMP 1671 CONFIG_CFB_CONSOLE 1672 CONFIG_VIDEO_SW_CURSOR 1673 CONFIG_VGA_AS_SINGLE_DEVICE 1674 CONFIG_VIDEO_LOGO 1675 CONFIG_VIDEO_BMP_LOGO 1676 1677 The DIU driver will look for the 'video-mode' environment 1678 variable, and if defined, enable the DIU as a console during 1679 boot. See the documentation file README.video for a 1680 description of this variable. 1681 1682 CONFIG_VIDEO_VGA 1683 1684 Enable the VGA video / BIOS for x86. The alternative if you 1685 are using coreboot is to use the coreboot frame buffer 1686 driver. 1687 1688 1689- Keyboard Support: 1690 CONFIG_KEYBOARD 1691 1692 Define this to enable a custom keyboard support. 1693 This simply calls drv_keyboard_init() which must be 1694 defined in your board-specific files. 1695 The only board using this so far is RBC823. 1696 1697- LCD Support: CONFIG_LCD 1698 1699 Define this to enable LCD support (for output to LCD 1700 display); also select one of the supported displays 1701 by defining one of these: 1702 1703 CONFIG_ATMEL_LCD: 1704 1705 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1706 1707 CONFIG_NEC_NL6448AC33: 1708 1709 NEC NL6448AC33-18. Active, color, single scan. 1710 1711 CONFIG_NEC_NL6448BC20 1712 1713 NEC NL6448BC20-08. 6.5", 640x480. 1714 Active, color, single scan. 1715 1716 CONFIG_NEC_NL6448BC33_54 1717 1718 NEC NL6448BC33-54. 10.4", 640x480. 1719 Active, color, single scan. 1720 1721 CONFIG_SHARP_16x9 1722 1723 Sharp 320x240. Active, color, single scan. 1724 It isn't 16x9, and I am not sure what it is. 1725 1726 CONFIG_SHARP_LQ64D341 1727 1728 Sharp LQ64D341 display, 640x480. 1729 Active, color, single scan. 1730 1731 CONFIG_HLD1045 1732 1733 HLD1045 display, 640x480. 1734 Active, color, single scan. 1735 1736 CONFIG_OPTREX_BW 1737 1738 Optrex CBL50840-2 NF-FW 99 22 M5 1739 or 1740 Hitachi LMG6912RPFC-00T 1741 or 1742 Hitachi SP14Q002 1743 1744 320x240. Black & white. 1745 1746 Normally display is black on white background; define 1747 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1748 1749 CONFIG_LCD_ALIGNMENT 1750 1751 Normally the LCD is page-aligned (tyically 4KB). If this is 1752 defined then the LCD will be aligned to this value instead. 1753 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1754 here, since it is cheaper to change data cache settings on 1755 a per-section basis. 1756 1757 CONFIG_CONSOLE_SCROLL_LINES 1758 1759 When the console need to be scrolled, this is the number of 1760 lines to scroll by. It defaults to 1. Increasing this makes 1761 the console jump but can help speed up operation when scrolling 1762 is slow. 1763 1764 CONFIG_LCD_BMP_RLE8 1765 1766 Support drawing of RLE8-compressed bitmaps on the LCD. 1767 1768 CONFIG_I2C_EDID 1769 1770 Enables an 'i2c edid' command which can read EDID 1771 information over I2C from an attached LCD display. 1772 1773- Splash Screen Support: CONFIG_SPLASH_SCREEN 1774 1775 If this option is set, the environment is checked for 1776 a variable "splashimage". If found, the usual display 1777 of logo, copyright and system information on the LCD 1778 is suppressed and the BMP image at the address 1779 specified in "splashimage" is loaded instead. The 1780 console is redirected to the "nulldev", too. This 1781 allows for a "silent" boot where a splash screen is 1782 loaded very quickly after power-on. 1783 1784 CONFIG_SPLASHIMAGE_GUARD 1785 1786 If this option is set, then U-Boot will prevent the environment 1787 variable "splashimage" from being set to a problematic address 1788 (see README.displaying-bmps). 1789 This option is useful for targets where, due to alignment 1790 restrictions, an improperly aligned BMP image will cause a data 1791 abort. If you think you will not have problems with unaligned 1792 accesses (for example because your toolchain prevents them) 1793 there is no need to set this option. 1794 1795 CONFIG_SPLASH_SCREEN_ALIGN 1796 1797 If this option is set the splash image can be freely positioned 1798 on the screen. Environment variable "splashpos" specifies the 1799 position as "x,y". If a positive number is given it is used as 1800 number of pixel from left/top. If a negative number is given it 1801 is used as number of pixel from right/bottom. You can also 1802 specify 'm' for centering the image. 1803 1804 Example: 1805 setenv splashpos m,m 1806 => image at center of screen 1807 1808 setenv splashpos 30,20 1809 => image at x = 30 and y = 20 1810 1811 setenv splashpos -10,m 1812 => vertically centered image 1813 at x = dspWidth - bmpWidth - 9 1814 1815- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1816 1817 If this option is set, additionally to standard BMP 1818 images, gzipped BMP images can be displayed via the 1819 splashscreen support or the bmp command. 1820 1821- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1822 1823 If this option is set, 8-bit RLE compressed BMP images 1824 can be displayed via the splashscreen support or the 1825 bmp command. 1826 1827- Do compresssing for memory range: 1828 CONFIG_CMD_ZIP 1829 1830 If this option is set, it would use zlib deflate method 1831 to compress the specified memory at its best effort. 1832 1833- Compression support: 1834 CONFIG_GZIP 1835 1836 Enabled by default to support gzip compressed images. 1837 1838 CONFIG_BZIP2 1839 1840 If this option is set, support for bzip2 compressed 1841 images is included. If not, only uncompressed and gzip 1842 compressed images are supported. 1843 1844 NOTE: the bzip2 algorithm requires a lot of RAM, so 1845 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1846 be at least 4MB. 1847 1848 CONFIG_LZMA 1849 1850 If this option is set, support for lzma compressed 1851 images is included. 1852 1853 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1854 requires an amount of dynamic memory that is given by the 1855 formula: 1856 1857 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1858 1859 Where lc and lp stand for, respectively, Literal context bits 1860 and Literal pos bits. 1861 1862 This value is upper-bounded by 14MB in the worst case. Anyway, 1863 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1864 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1865 a very small buffer. 1866 1867 Use the lzmainfo tool to determinate the lc and lp values and 1868 then calculate the amount of needed dynamic memory (ensuring 1869 the appropriate CONFIG_SYS_MALLOC_LEN value). 1870 1871 CONFIG_LZO 1872 1873 If this option is set, support for LZO compressed images 1874 is included. 1875 1876- MII/PHY support: 1877 CONFIG_PHY_ADDR 1878 1879 The address of PHY on MII bus. 1880 1881 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1882 1883 The clock frequency of the MII bus 1884 1885 CONFIG_PHY_GIGE 1886 1887 If this option is set, support for speed/duplex 1888 detection of gigabit PHY is included. 1889 1890 CONFIG_PHY_RESET_DELAY 1891 1892 Some PHY like Intel LXT971A need extra delay after 1893 reset before any MII register access is possible. 1894 For such PHY, set this option to the usec delay 1895 required. (minimum 300usec for LXT971A) 1896 1897 CONFIG_PHY_CMD_DELAY (ppc4xx) 1898 1899 Some PHY like Intel LXT971A need extra delay after 1900 command issued before MII status register can be read 1901 1902- Ethernet address: 1903 CONFIG_ETHADDR 1904 CONFIG_ETH1ADDR 1905 CONFIG_ETH2ADDR 1906 CONFIG_ETH3ADDR 1907 CONFIG_ETH4ADDR 1908 CONFIG_ETH5ADDR 1909 1910 Define a default value for Ethernet address to use 1911 for the respective Ethernet interface, in case this 1912 is not determined automatically. 1913 1914- IP address: 1915 CONFIG_IPADDR 1916 1917 Define a default value for the IP address to use for 1918 the default Ethernet interface, in case this is not 1919 determined through e.g. bootp. 1920 (Environment variable "ipaddr") 1921 1922- Server IP address: 1923 CONFIG_SERVERIP 1924 1925 Defines a default value for the IP address of a TFTP 1926 server to contact when using the "tftboot" command. 1927 (Environment variable "serverip") 1928 1929 CONFIG_KEEP_SERVERADDR 1930 1931 Keeps the server's MAC address, in the env 'serveraddr' 1932 for passing to bootargs (like Linux's netconsole option) 1933 1934- Gateway IP address: 1935 CONFIG_GATEWAYIP 1936 1937 Defines a default value for the IP address of the 1938 default router where packets to other networks are 1939 sent to. 1940 (Environment variable "gatewayip") 1941 1942- Subnet mask: 1943 CONFIG_NETMASK 1944 1945 Defines a default value for the subnet mask (or 1946 routing prefix) which is used to determine if an IP 1947 address belongs to the local subnet or needs to be 1948 forwarded through a router. 1949 (Environment variable "netmask") 1950 1951- Multicast TFTP Mode: 1952 CONFIG_MCAST_TFTP 1953 1954 Defines whether you want to support multicast TFTP as per 1955 rfc-2090; for example to work with atftp. Lets lots of targets 1956 tftp down the same boot image concurrently. Note: the Ethernet 1957 driver in use must provide a function: mcast() to join/leave a 1958 multicast group. 1959 1960- BOOTP Recovery Mode: 1961 CONFIG_BOOTP_RANDOM_DELAY 1962 1963 If you have many targets in a network that try to 1964 boot using BOOTP, you may want to avoid that all 1965 systems send out BOOTP requests at precisely the same 1966 moment (which would happen for instance at recovery 1967 from a power failure, when all systems will try to 1968 boot, thus flooding the BOOTP server. Defining 1969 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1970 inserted before sending out BOOTP requests. The 1971 following delays are inserted then: 1972 1973 1st BOOTP request: delay 0 ... 1 sec 1974 2nd BOOTP request: delay 0 ... 2 sec 1975 3rd BOOTP request: delay 0 ... 4 sec 1976 4th and following 1977 BOOTP requests: delay 0 ... 8 sec 1978 1979- DHCP Advanced Options: 1980 You can fine tune the DHCP functionality by defining 1981 CONFIG_BOOTP_* symbols: 1982 1983 CONFIG_BOOTP_SUBNETMASK 1984 CONFIG_BOOTP_GATEWAY 1985 CONFIG_BOOTP_HOSTNAME 1986 CONFIG_BOOTP_NISDOMAIN 1987 CONFIG_BOOTP_BOOTPATH 1988 CONFIG_BOOTP_BOOTFILESIZE 1989 CONFIG_BOOTP_DNS 1990 CONFIG_BOOTP_DNS2 1991 CONFIG_BOOTP_SEND_HOSTNAME 1992 CONFIG_BOOTP_NTPSERVER 1993 CONFIG_BOOTP_TIMEOFFSET 1994 CONFIG_BOOTP_VENDOREX 1995 CONFIG_BOOTP_MAY_FAIL 1996 1997 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1998 environment variable, not the BOOTP server. 1999 2000 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2001 after the configured retry count, the call will fail 2002 instead of starting over. This can be used to fail over 2003 to Link-local IP address configuration if the DHCP server 2004 is not available. 2005 2006 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2007 serverip from a DHCP server, it is possible that more 2008 than one DNS serverip is offered to the client. 2009 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2010 serverip will be stored in the additional environment 2011 variable "dnsip2". The first DNS serverip is always 2012 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2013 is defined. 2014 2015 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2016 to do a dynamic update of a DNS server. To do this, they 2017 need the hostname of the DHCP requester. 2018 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2019 of the "hostname" environment variable is passed as 2020 option 12 to the DHCP server. 2021 2022 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2023 2024 A 32bit value in microseconds for a delay between 2025 receiving a "DHCP Offer" and sending the "DHCP Request". 2026 This fixes a problem with certain DHCP servers that don't 2027 respond 100% of the time to a "DHCP request". E.g. On an 2028 AT91RM9200 processor running at 180MHz, this delay needed 2029 to be *at least* 15,000 usec before a Windows Server 2003 2030 DHCP server would reply 100% of the time. I recommend at 2031 least 50,000 usec to be safe. The alternative is to hope 2032 that one of the retries will be successful but note that 2033 the DHCP timeout and retry process takes a longer than 2034 this delay. 2035 2036 - Link-local IP address negotiation: 2037 Negotiate with other link-local clients on the local network 2038 for an address that doesn't require explicit configuration. 2039 This is especially useful if a DHCP server cannot be guaranteed 2040 to exist in all environments that the device must operate. 2041 2042 See doc/README.link-local for more information. 2043 2044 - CDP Options: 2045 CONFIG_CDP_DEVICE_ID 2046 2047 The device id used in CDP trigger frames. 2048 2049 CONFIG_CDP_DEVICE_ID_PREFIX 2050 2051 A two character string which is prefixed to the MAC address 2052 of the device. 2053 2054 CONFIG_CDP_PORT_ID 2055 2056 A printf format string which contains the ascii name of 2057 the port. Normally is set to "eth%d" which sets 2058 eth0 for the first Ethernet, eth1 for the second etc. 2059 2060 CONFIG_CDP_CAPABILITIES 2061 2062 A 32bit integer which indicates the device capabilities; 2063 0x00000010 for a normal host which does not forwards. 2064 2065 CONFIG_CDP_VERSION 2066 2067 An ascii string containing the version of the software. 2068 2069 CONFIG_CDP_PLATFORM 2070 2071 An ascii string containing the name of the platform. 2072 2073 CONFIG_CDP_TRIGGER 2074 2075 A 32bit integer sent on the trigger. 2076 2077 CONFIG_CDP_POWER_CONSUMPTION 2078 2079 A 16bit integer containing the power consumption of the 2080 device in .1 of milliwatts. 2081 2082 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2083 2084 A byte containing the id of the VLAN. 2085 2086- Status LED: CONFIG_STATUS_LED 2087 2088 Several configurations allow to display the current 2089 status using a LED. For instance, the LED will blink 2090 fast while running U-Boot code, stop blinking as 2091 soon as a reply to a BOOTP request was received, and 2092 start blinking slow once the Linux kernel is running 2093 (supported by a status LED driver in the Linux 2094 kernel). Defining CONFIG_STATUS_LED enables this 2095 feature in U-Boot. 2096 2097 Additional options: 2098 2099 CONFIG_GPIO_LED 2100 The status LED can be connected to a GPIO pin. 2101 In such cases, the gpio_led driver can be used as a 2102 status LED backend implementation. Define CONFIG_GPIO_LED 2103 to include the gpio_led driver in the U-Boot binary. 2104 2105 CONFIG_GPIO_LED_INVERTED_TABLE 2106 Some GPIO connected LEDs may have inverted polarity in which 2107 case the GPIO high value corresponds to LED off state and 2108 GPIO low value corresponds to LED on state. 2109 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2110 with a list of GPIO LEDs that have inverted polarity. 2111 2112- CAN Support: CONFIG_CAN_DRIVER 2113 2114 Defining CONFIG_CAN_DRIVER enables CAN driver support 2115 on those systems that support this (optional) 2116 feature, like the TQM8xxL modules. 2117 2118- I2C Support: CONFIG_SYS_I2C 2119 2120 This enable the NEW i2c subsystem, and will allow you to use 2121 i2c commands at the u-boot command line (as long as you set 2122 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2123 based realtime clock chips or other i2c devices. See 2124 common/cmd_i2c.c for a description of the command line 2125 interface. 2126 2127 ported i2c driver to the new framework: 2128 - drivers/i2c/soft_i2c.c: 2129 - activate first bus with CONFIG_SYS_I2C_SOFT define 2130 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2131 for defining speed and slave address 2132 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2133 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2134 for defining speed and slave address 2135 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2136 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2137 for defining speed and slave address 2138 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2139 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2140 for defining speed and slave address 2141 2142 - drivers/i2c/fsl_i2c.c: 2143 - activate i2c driver with CONFIG_SYS_I2C_FSL 2144 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2145 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2146 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2147 bus. 2148 - If your board supports a second fsl i2c bus, define 2149 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2150 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2151 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2152 second bus. 2153 2154 - drivers/i2c/tegra_i2c.c: 2155 - activate this driver with CONFIG_SYS_I2C_TEGRA 2156 - This driver adds 4 i2c buses with a fix speed from 2157 100000 and the slave addr 0! 2158 2159 - drivers/i2c/ppc4xx_i2c.c 2160 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2161 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2162 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2163 2164 - drivers/i2c/i2c_mxc.c 2165 - activate this driver with CONFIG_SYS_I2C_MXC 2166 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2167 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2168 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2169 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2170 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2171 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2172 If thoses defines are not set, default value is 100000 2173 for speed, and 0 for slave. 2174 2175 - drivers/i2c/rcar_i2c.c: 2176 - activate this driver with CONFIG_SYS_I2C_RCAR 2177 - This driver adds 4 i2c buses 2178 2179 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2180 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2181 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2182 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2183 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2184 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2185 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2186 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2187 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2188 2189 - drivers/i2c/sh_i2c.c: 2190 - activate this driver with CONFIG_SYS_I2C_SH 2191 - This driver adds from 2 to 5 i2c buses 2192 2193 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2194 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2195 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2196 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2197 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2198 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2199 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2200 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2201 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2202 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2203 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2204 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2205 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses 2206 2207 - drivers/i2c/omap24xx_i2c.c 2208 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2209 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2210 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2211 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2212 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2213 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2214 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2215 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2216 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2217 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2218 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2219 2220 - drivers/i2c/zynq_i2c.c 2221 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2222 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2223 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2224 2225 - drivers/i2c/s3c24x0_i2c.c: 2226 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2227 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2228 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2229 with a fix speed from 100000 and the slave addr 0! 2230 2231 additional defines: 2232 2233 CONFIG_SYS_NUM_I2C_BUSES 2234 Hold the number of i2c busses you want to use. If you 2235 don't use/have i2c muxes on your i2c bus, this 2236 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2237 omit this define. 2238 2239 CONFIG_SYS_I2C_DIRECT_BUS 2240 define this, if you don't use i2c muxes on your hardware. 2241 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2242 omit this define. 2243 2244 CONFIG_SYS_I2C_MAX_HOPS 2245 define how many muxes are maximal consecutively connected 2246 on one i2c bus. If you not use i2c muxes, omit this 2247 define. 2248 2249 CONFIG_SYS_I2C_BUSES 2250 hold a list of busses you want to use, only used if 2251 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2252 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2253 CONFIG_SYS_NUM_I2C_BUSES = 9: 2254 2255 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2256 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2257 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2258 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2259 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2260 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2261 {1, {I2C_NULL_HOP}}, \ 2262 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2263 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2264 } 2265 2266 which defines 2267 bus 0 on adapter 0 without a mux 2268 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2269 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2270 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2271 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2272 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2273 bus 6 on adapter 1 without a mux 2274 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2275 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2276 2277 If you do not have i2c muxes on your board, omit this define. 2278 2279- Legacy I2C Support: CONFIG_HARD_I2C 2280 2281 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2282 provides the following compelling advantages: 2283 2284 - more than one i2c adapter is usable 2285 - approved multibus support 2286 - better i2c mux support 2287 2288 ** Please consider updating your I2C driver now. ** 2289 2290 These enable legacy I2C serial bus commands. Defining 2291 CONFIG_HARD_I2C will include the appropriate I2C driver 2292 for the selected CPU. 2293 2294 This will allow you to use i2c commands at the u-boot 2295 command line (as long as you set CONFIG_CMD_I2C in 2296 CONFIG_COMMANDS) and communicate with i2c based realtime 2297 clock chips. See common/cmd_i2c.c for a description of the 2298 command line interface. 2299 2300 CONFIG_HARD_I2C selects a hardware I2C controller. 2301 2302 There are several other quantities that must also be 2303 defined when you define CONFIG_HARD_I2C. 2304 2305 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2306 to be the frequency (in Hz) at which you wish your i2c bus 2307 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2308 the CPU's i2c node address). 2309 2310 Now, the u-boot i2c code for the mpc8xx 2311 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2312 and so its address should therefore be cleared to 0 (See, 2313 eg, MPC823e User's Manual p.16-473). So, set 2314 CONFIG_SYS_I2C_SLAVE to 0. 2315 2316 CONFIG_SYS_I2C_INIT_MPC5XXX 2317 2318 When a board is reset during an i2c bus transfer 2319 chips might think that the current transfer is still 2320 in progress. Reset the slave devices by sending start 2321 commands until the slave device responds. 2322 2323 That's all that's required for CONFIG_HARD_I2C. 2324 2325 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2326 then the following macros need to be defined (examples are 2327 from include/configs/lwmon.h): 2328 2329 I2C_INIT 2330 2331 (Optional). Any commands necessary to enable the I2C 2332 controller or configure ports. 2333 2334 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2335 2336 I2C_PORT 2337 2338 (Only for MPC8260 CPU). The I/O port to use (the code 2339 assumes both bits are on the same port). Valid values 2340 are 0..3 for ports A..D. 2341 2342 I2C_ACTIVE 2343 2344 The code necessary to make the I2C data line active 2345 (driven). If the data line is open collector, this 2346 define can be null. 2347 2348 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2349 2350 I2C_TRISTATE 2351 2352 The code necessary to make the I2C data line tri-stated 2353 (inactive). If the data line is open collector, this 2354 define can be null. 2355 2356 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2357 2358 I2C_READ 2359 2360 Code that returns true if the I2C data line is high, 2361 false if it is low. 2362 2363 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2364 2365 I2C_SDA(bit) 2366 2367 If <bit> is true, sets the I2C data line high. If it 2368 is false, it clears it (low). 2369 2370 eg: #define I2C_SDA(bit) \ 2371 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2372 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2373 2374 I2C_SCL(bit) 2375 2376 If <bit> is true, sets the I2C clock line high. If it 2377 is false, it clears it (low). 2378 2379 eg: #define I2C_SCL(bit) \ 2380 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2381 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2382 2383 I2C_DELAY 2384 2385 This delay is invoked four times per clock cycle so this 2386 controls the rate of data transfer. The data rate thus 2387 is 1 / (I2C_DELAY * 4). Often defined to be something 2388 like: 2389 2390 #define I2C_DELAY udelay(2) 2391 2392 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2393 2394 If your arch supports the generic GPIO framework (asm/gpio.h), 2395 then you may alternatively define the two GPIOs that are to be 2396 used as SCL / SDA. Any of the previous I2C_xxx macros will 2397 have GPIO-based defaults assigned to them as appropriate. 2398 2399 You should define these to the GPIO value as given directly to 2400 the generic GPIO functions. 2401 2402 CONFIG_SYS_I2C_INIT_BOARD 2403 2404 When a board is reset during an i2c bus transfer 2405 chips might think that the current transfer is still 2406 in progress. On some boards it is possible to access 2407 the i2c SCLK line directly, either by using the 2408 processor pin as a GPIO or by having a second pin 2409 connected to the bus. If this option is defined a 2410 custom i2c_init_board() routine in boards/xxx/board.c 2411 is run early in the boot sequence. 2412 2413 CONFIG_SYS_I2C_BOARD_LATE_INIT 2414 2415 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2416 defined a custom i2c_board_late_init() routine in 2417 boards/xxx/board.c is run AFTER the operations in i2c_init() 2418 is completed. This callpoint can be used to unreset i2c bus 2419 using CPU i2c controller register accesses for CPUs whose i2c 2420 controller provide such a method. It is called at the end of 2421 i2c_init() to allow i2c_init operations to setup the i2c bus 2422 controller on the CPU (e.g. setting bus speed & slave address). 2423 2424 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2425 2426 This option enables configuration of bi_iic_fast[] flags 2427 in u-boot bd_info structure based on u-boot environment 2428 variable "i2cfast". (see also i2cfast) 2429 2430 CONFIG_I2C_MULTI_BUS 2431 2432 This option allows the use of multiple I2C buses, each of which 2433 must have a controller. At any point in time, only one bus is 2434 active. To switch to a different bus, use the 'i2c dev' command. 2435 Note that bus numbering is zero-based. 2436 2437 CONFIG_SYS_I2C_NOPROBES 2438 2439 This option specifies a list of I2C devices that will be skipped 2440 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2441 is set, specify a list of bus-device pairs. Otherwise, specify 2442 a 1D array of device addresses 2443 2444 e.g. 2445 #undef CONFIG_I2C_MULTI_BUS 2446 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2447 2448 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2449 2450 #define CONFIG_I2C_MULTI_BUS 2451 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2452 2453 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2454 2455 CONFIG_SYS_SPD_BUS_NUM 2456 2457 If defined, then this indicates the I2C bus number for DDR SPD. 2458 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2459 2460 CONFIG_SYS_RTC_BUS_NUM 2461 2462 If defined, then this indicates the I2C bus number for the RTC. 2463 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2464 2465 CONFIG_SYS_DTT_BUS_NUM 2466 2467 If defined, then this indicates the I2C bus number for the DTT. 2468 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2469 2470 CONFIG_SYS_I2C_DTT_ADDR: 2471 2472 If defined, specifies the I2C address of the DTT device. 2473 If not defined, then U-Boot uses predefined value for 2474 specified DTT device. 2475 2476 CONFIG_SOFT_I2C_READ_REPEATED_START 2477 2478 defining this will force the i2c_read() function in 2479 the soft_i2c driver to perform an I2C repeated start 2480 between writing the address pointer and reading the 2481 data. If this define is omitted the default behaviour 2482 of doing a stop-start sequence will be used. Most I2C 2483 devices can use either method, but some require one or 2484 the other. 2485 2486- SPI Support: CONFIG_SPI 2487 2488 Enables SPI driver (so far only tested with 2489 SPI EEPROM, also an instance works with Crystal A/D and 2490 D/As on the SACSng board) 2491 2492 CONFIG_SH_SPI 2493 2494 Enables the driver for SPI controller on SuperH. Currently 2495 only SH7757 is supported. 2496 2497 CONFIG_SPI_X 2498 2499 Enables extended (16-bit) SPI EEPROM addressing. 2500 (symmetrical to CONFIG_I2C_X) 2501 2502 CONFIG_SOFT_SPI 2503 2504 Enables a software (bit-bang) SPI driver rather than 2505 using hardware support. This is a general purpose 2506 driver that only requires three general I/O port pins 2507 (two outputs, one input) to function. If this is 2508 defined, the board configuration must define several 2509 SPI configuration items (port pins to use, etc). For 2510 an example, see include/configs/sacsng.h. 2511 2512 CONFIG_HARD_SPI 2513 2514 Enables a hardware SPI driver for general-purpose reads 2515 and writes. As with CONFIG_SOFT_SPI, the board configuration 2516 must define a list of chip-select function pointers. 2517 Currently supported on some MPC8xxx processors. For an 2518 example, see include/configs/mpc8349emds.h. 2519 2520 CONFIG_MXC_SPI 2521 2522 Enables the driver for the SPI controllers on i.MX and MXC 2523 SoCs. Currently i.MX31/35/51 are supported. 2524 2525- FPGA Support: CONFIG_FPGA 2526 2527 Enables FPGA subsystem. 2528 2529 CONFIG_FPGA_<vendor> 2530 2531 Enables support for specific chip vendors. 2532 (ALTERA, XILINX) 2533 2534 CONFIG_FPGA_<family> 2535 2536 Enables support for FPGA family. 2537 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2538 2539 CONFIG_FPGA_COUNT 2540 2541 Specify the number of FPGA devices to support. 2542 2543 CONFIG_SYS_FPGA_PROG_FEEDBACK 2544 2545 Enable printing of hash marks during FPGA configuration. 2546 2547 CONFIG_SYS_FPGA_CHECK_BUSY 2548 2549 Enable checks on FPGA configuration interface busy 2550 status by the configuration function. This option 2551 will require a board or device specific function to 2552 be written. 2553 2554 CONFIG_FPGA_DELAY 2555 2556 If defined, a function that provides delays in the FPGA 2557 configuration driver. 2558 2559 CONFIG_SYS_FPGA_CHECK_CTRLC 2560 Allow Control-C to interrupt FPGA configuration 2561 2562 CONFIG_SYS_FPGA_CHECK_ERROR 2563 2564 Check for configuration errors during FPGA bitfile 2565 loading. For example, abort during Virtex II 2566 configuration if the INIT_B line goes low (which 2567 indicated a CRC error). 2568 2569 CONFIG_SYS_FPGA_WAIT_INIT 2570 2571 Maximum time to wait for the INIT_B line to deassert 2572 after PROB_B has been deasserted during a Virtex II 2573 FPGA configuration sequence. The default time is 500 2574 ms. 2575 2576 CONFIG_SYS_FPGA_WAIT_BUSY 2577 2578 Maximum time to wait for BUSY to deassert during 2579 Virtex II FPGA configuration. The default is 5 ms. 2580 2581 CONFIG_SYS_FPGA_WAIT_CONFIG 2582 2583 Time to wait after FPGA configuration. The default is 2584 200 ms. 2585 2586- Configuration Management: 2587 CONFIG_IDENT_STRING 2588 2589 If defined, this string will be added to the U-Boot 2590 version information (U_BOOT_VERSION) 2591 2592- Vendor Parameter Protection: 2593 2594 U-Boot considers the values of the environment 2595 variables "serial#" (Board Serial Number) and 2596 "ethaddr" (Ethernet Address) to be parameters that 2597 are set once by the board vendor / manufacturer, and 2598 protects these variables from casual modification by 2599 the user. Once set, these variables are read-only, 2600 and write or delete attempts are rejected. You can 2601 change this behaviour: 2602 2603 If CONFIG_ENV_OVERWRITE is #defined in your config 2604 file, the write protection for vendor parameters is 2605 completely disabled. Anybody can change or delete 2606 these parameters. 2607 2608 Alternatively, if you #define _both_ CONFIG_ETHADDR 2609 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2610 Ethernet address is installed in the environment, 2611 which can be changed exactly ONCE by the user. [The 2612 serial# is unaffected by this, i. e. it remains 2613 read-only.] 2614 2615 The same can be accomplished in a more flexible way 2616 for any variable by configuring the type of access 2617 to allow for those variables in the ".flags" variable 2618 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2619 2620- Protected RAM: 2621 CONFIG_PRAM 2622 2623 Define this variable to enable the reservation of 2624 "protected RAM", i. e. RAM which is not overwritten 2625 by U-Boot. Define CONFIG_PRAM to hold the number of 2626 kB you want to reserve for pRAM. You can overwrite 2627 this default value by defining an environment 2628 variable "pram" to the number of kB you want to 2629 reserve. Note that the board info structure will 2630 still show the full amount of RAM. If pRAM is 2631 reserved, a new environment variable "mem" will 2632 automatically be defined to hold the amount of 2633 remaining RAM in a form that can be passed as boot 2634 argument to Linux, for instance like that: 2635 2636 setenv bootargs ... mem=\${mem} 2637 saveenv 2638 2639 This way you can tell Linux not to use this memory, 2640 either, which results in a memory region that will 2641 not be affected by reboots. 2642 2643 *WARNING* If your board configuration uses automatic 2644 detection of the RAM size, you must make sure that 2645 this memory test is non-destructive. So far, the 2646 following board configurations are known to be 2647 "pRAM-clean": 2648 2649 IVMS8, IVML24, SPD8xx, TQM8xxL, 2650 HERMES, IP860, RPXlite, LWMON, 2651 FLAGADM, TQM8260 2652 2653- Access to physical memory region (> 4GB) 2654 Some basic support is provided for operations on memory not 2655 normally accessible to U-Boot - e.g. some architectures 2656 support access to more than 4GB of memory on 32-bit 2657 machines using physical address extension or similar. 2658 Define CONFIG_PHYSMEM to access this basic support, which 2659 currently only supports clearing the memory. 2660 2661- Error Recovery: 2662 CONFIG_PANIC_HANG 2663 2664 Define this variable to stop the system in case of a 2665 fatal error, so that you have to reset it manually. 2666 This is probably NOT a good idea for an embedded 2667 system where you want the system to reboot 2668 automatically as fast as possible, but it may be 2669 useful during development since you can try to debug 2670 the conditions that lead to the situation. 2671 2672 CONFIG_NET_RETRY_COUNT 2673 2674 This variable defines the number of retries for 2675 network operations like ARP, RARP, TFTP, or BOOTP 2676 before giving up the operation. If not defined, a 2677 default value of 5 is used. 2678 2679 CONFIG_ARP_TIMEOUT 2680 2681 Timeout waiting for an ARP reply in milliseconds. 2682 2683 CONFIG_NFS_TIMEOUT 2684 2685 Timeout in milliseconds used in NFS protocol. 2686 If you encounter "ERROR: Cannot umount" in nfs command, 2687 try longer timeout such as 2688 #define CONFIG_NFS_TIMEOUT 10000UL 2689 2690- Command Interpreter: 2691 CONFIG_AUTO_COMPLETE 2692 2693 Enable auto completion of commands using TAB. 2694 2695 Note that this feature has NOT been implemented yet 2696 for the "hush" shell. 2697 2698 2699 CONFIG_SYS_HUSH_PARSER 2700 2701 Define this variable to enable the "hush" shell (from 2702 Busybox) as command line interpreter, thus enabling 2703 powerful command line syntax like 2704 if...then...else...fi conditionals or `&&' and '||' 2705 constructs ("shell scripts"). 2706 2707 If undefined, you get the old, much simpler behaviour 2708 with a somewhat smaller memory footprint. 2709 2710 2711 CONFIG_SYS_PROMPT_HUSH_PS2 2712 2713 This defines the secondary prompt string, which is 2714 printed when the command interpreter needs more input 2715 to complete a command. Usually "> ". 2716 2717 Note: 2718 2719 In the current implementation, the local variables 2720 space and global environment variables space are 2721 separated. Local variables are those you define by 2722 simply typing `name=value'. To access a local 2723 variable later on, you have write `$name' or 2724 `${name}'; to execute the contents of a variable 2725 directly type `$name' at the command prompt. 2726 2727 Global environment variables are those you use 2728 setenv/printenv to work with. To run a command stored 2729 in such a variable, you need to use the run command, 2730 and you must not use the '$' sign to access them. 2731 2732 To store commands and special characters in a 2733 variable, please use double quotation marks 2734 surrounding the whole text of the variable, instead 2735 of the backslashes before semicolons and special 2736 symbols. 2737 2738- Commandline Editing and History: 2739 CONFIG_CMDLINE_EDITING 2740 2741 Enable editing and History functions for interactive 2742 commandline input operations 2743 2744- Default Environment: 2745 CONFIG_EXTRA_ENV_SETTINGS 2746 2747 Define this to contain any number of null terminated 2748 strings (variable = value pairs) that will be part of 2749 the default environment compiled into the boot image. 2750 2751 For example, place something like this in your 2752 board's config file: 2753 2754 #define CONFIG_EXTRA_ENV_SETTINGS \ 2755 "myvar1=value1\0" \ 2756 "myvar2=value2\0" 2757 2758 Warning: This method is based on knowledge about the 2759 internal format how the environment is stored by the 2760 U-Boot code. This is NOT an official, exported 2761 interface! Although it is unlikely that this format 2762 will change soon, there is no guarantee either. 2763 You better know what you are doing here. 2764 2765 Note: overly (ab)use of the default environment is 2766 discouraged. Make sure to check other ways to preset 2767 the environment like the "source" command or the 2768 boot command first. 2769 2770 CONFIG_ENV_VARS_UBOOT_CONFIG 2771 2772 Define this in order to add variables describing the 2773 U-Boot build configuration to the default environment. 2774 These will be named arch, cpu, board, vendor, and soc. 2775 2776 Enabling this option will cause the following to be defined: 2777 2778 - CONFIG_SYS_ARCH 2779 - CONFIG_SYS_CPU 2780 - CONFIG_SYS_BOARD 2781 - CONFIG_SYS_VENDOR 2782 - CONFIG_SYS_SOC 2783 2784 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2785 2786 Define this in order to add variables describing certain 2787 run-time determined information about the hardware to the 2788 environment. These will be named board_name, board_rev. 2789 2790 CONFIG_DELAY_ENVIRONMENT 2791 2792 Normally the environment is loaded when the board is 2793 intialised so that it is available to U-Boot. This inhibits 2794 that so that the environment is not available until 2795 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2796 this is instead controlled by the value of 2797 /config/load-environment. 2798 2799- DataFlash Support: 2800 CONFIG_HAS_DATAFLASH 2801 2802 Defining this option enables DataFlash features and 2803 allows to read/write in Dataflash via the standard 2804 commands cp, md... 2805 2806- Serial Flash support 2807 CONFIG_CMD_SF 2808 2809 Defining this option enables SPI flash commands 2810 'sf probe/read/write/erase/update'. 2811 2812 Usage requires an initial 'probe' to define the serial 2813 flash parameters, followed by read/write/erase/update 2814 commands. 2815 2816 The following defaults may be provided by the platform 2817 to handle the common case when only a single serial 2818 flash is present on the system. 2819 2820 CONFIG_SF_DEFAULT_BUS Bus identifier 2821 CONFIG_SF_DEFAULT_CS Chip-select 2822 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2823 CONFIG_SF_DEFAULT_SPEED in Hz 2824 2825 CONFIG_CMD_SF_TEST 2826 2827 Define this option to include a destructive SPI flash 2828 test ('sf test'). 2829 2830 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg 2831 2832 Define this option to use the Bank addr/Extended addr 2833 support on SPI flashes which has size > 16Mbytes. 2834 2835 CONFIG_SF_DUAL_FLASH Dual flash memories 2836 2837 Define this option to use dual flash support where two flash 2838 memories can be connected with a given cs line. 2839 currently Xilinx Zynq qspi support these type of connections. 2840 2841- SystemACE Support: 2842 CONFIG_SYSTEMACE 2843 2844 Adding this option adds support for Xilinx SystemACE 2845 chips attached via some sort of local bus. The address 2846 of the chip must also be defined in the 2847 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2848 2849 #define CONFIG_SYSTEMACE 2850 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2851 2852 When SystemACE support is added, the "ace" device type 2853 becomes available to the fat commands, i.e. fatls. 2854 2855- TFTP Fixed UDP Port: 2856 CONFIG_TFTP_PORT 2857 2858 If this is defined, the environment variable tftpsrcp 2859 is used to supply the TFTP UDP source port value. 2860 If tftpsrcp isn't defined, the normal pseudo-random port 2861 number generator is used. 2862 2863 Also, the environment variable tftpdstp is used to supply 2864 the TFTP UDP destination port value. If tftpdstp isn't 2865 defined, the normal port 69 is used. 2866 2867 The purpose for tftpsrcp is to allow a TFTP server to 2868 blindly start the TFTP transfer using the pre-configured 2869 target IP address and UDP port. This has the effect of 2870 "punching through" the (Windows XP) firewall, allowing 2871 the remainder of the TFTP transfer to proceed normally. 2872 A better solution is to properly configure the firewall, 2873 but sometimes that is not allowed. 2874 2875- Hashing support: 2876 CONFIG_CMD_HASH 2877 2878 This enables a generic 'hash' command which can produce 2879 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2880 2881 CONFIG_HASH_VERIFY 2882 2883 Enable the hash verify command (hash -v). This adds to code 2884 size a little. 2885 2886 CONFIG_SHA1 - support SHA1 hashing 2887 CONFIG_SHA256 - support SHA256 hashing 2888 2889 Note: There is also a sha1sum command, which should perhaps 2890 be deprecated in favour of 'hash sha1'. 2891 2892- Freescale i.MX specific commands: 2893 CONFIG_CMD_HDMIDETECT 2894 This enables 'hdmidet' command which returns true if an 2895 HDMI monitor is detected. This command is i.MX 6 specific. 2896 2897 CONFIG_CMD_BMODE 2898 This enables the 'bmode' (bootmode) command for forcing 2899 a boot from specific media. 2900 2901 This is useful for forcing the ROM's usb downloader to 2902 activate upon a watchdog reset which is nice when iterating 2903 on U-Boot. Using the reset button or running bmode normal 2904 will set it back to normal. This command currently 2905 supports i.MX53 and i.MX6. 2906 2907- Signing support: 2908 CONFIG_RSA 2909 2910 This enables the RSA algorithm used for FIT image verification 2911 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 2912 2913 The signing part is build into mkimage regardless of this 2914 option. 2915 2916- bootcount support: 2917 CONFIG_BOOTCOUNT_LIMIT 2918 2919 This enables the bootcounter support, see: 2920 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2921 2922 CONFIG_AT91SAM9XE 2923 enable special bootcounter support on at91sam9xe based boards. 2924 CONFIG_BLACKFIN 2925 enable special bootcounter support on blackfin based boards. 2926 CONFIG_SOC_DA8XX 2927 enable special bootcounter support on da850 based boards. 2928 CONFIG_BOOTCOUNT_RAM 2929 enable support for the bootcounter in RAM 2930 CONFIG_BOOTCOUNT_I2C 2931 enable support for the bootcounter on an i2c (like RTC) device. 2932 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2933 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2934 the bootcounter. 2935 CONFIG_BOOTCOUNT_ALEN = address len 2936 2937- Show boot progress: 2938 CONFIG_SHOW_BOOT_PROGRESS 2939 2940 Defining this option allows to add some board- 2941 specific code (calling a user-provided function 2942 "show_boot_progress(int)") that enables you to show 2943 the system's boot progress on some display (for 2944 example, some LED's) on your board. At the moment, 2945 the following checkpoints are implemented: 2946 2947- Detailed boot stage timing 2948 CONFIG_BOOTSTAGE 2949 Define this option to get detailed timing of each stage 2950 of the boot process. 2951 2952 CONFIG_BOOTSTAGE_USER_COUNT 2953 This is the number of available user bootstage records. 2954 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 2955 a new ID will be allocated from this stash. If you exceed 2956 the limit, recording will stop. 2957 2958 CONFIG_BOOTSTAGE_REPORT 2959 Define this to print a report before boot, similar to this: 2960 2961 Timer summary in microseconds: 2962 Mark Elapsed Stage 2963 0 0 reset 2964 3,575,678 3,575,678 board_init_f start 2965 3,575,695 17 arch_cpu_init A9 2966 3,575,777 82 arch_cpu_init done 2967 3,659,598 83,821 board_init_r start 2968 3,910,375 250,777 main_loop 2969 29,916,167 26,005,792 bootm_start 2970 30,361,327 445,160 start_kernel 2971 2972 CONFIG_CMD_BOOTSTAGE 2973 Add a 'bootstage' command which supports printing a report 2974 and un/stashing of bootstage data. 2975 2976 CONFIG_BOOTSTAGE_FDT 2977 Stash the bootstage information in the FDT. A root 'bootstage' 2978 node is created with each bootstage id as a child. Each child 2979 has a 'name' property and either 'mark' containing the 2980 mark time in microsecond, or 'accum' containing the 2981 accumulated time for that bootstage id in microseconds. 2982 For example: 2983 2984 bootstage { 2985 154 { 2986 name = "board_init_f"; 2987 mark = <3575678>; 2988 }; 2989 170 { 2990 name = "lcd"; 2991 accum = <33482>; 2992 }; 2993 }; 2994 2995 Code in the Linux kernel can find this in /proc/devicetree. 2996 2997Legacy uImage format: 2998 2999 Arg Where When 3000 1 common/cmd_bootm.c before attempting to boot an image 3001 -1 common/cmd_bootm.c Image header has bad magic number 3002 2 common/cmd_bootm.c Image header has correct magic number 3003 -2 common/cmd_bootm.c Image header has bad checksum 3004 3 common/cmd_bootm.c Image header has correct checksum 3005 -3 common/cmd_bootm.c Image data has bad checksum 3006 4 common/cmd_bootm.c Image data has correct checksum 3007 -4 common/cmd_bootm.c Image is for unsupported architecture 3008 5 common/cmd_bootm.c Architecture check OK 3009 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3010 6 common/cmd_bootm.c Image Type check OK 3011 -6 common/cmd_bootm.c gunzip uncompression error 3012 -7 common/cmd_bootm.c Unimplemented compression type 3013 7 common/cmd_bootm.c Uncompression OK 3014 8 common/cmd_bootm.c No uncompress/copy overwrite error 3015 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3016 3017 9 common/image.c Start initial ramdisk verification 3018 -10 common/image.c Ramdisk header has bad magic number 3019 -11 common/image.c Ramdisk header has bad checksum 3020 10 common/image.c Ramdisk header is OK 3021 -12 common/image.c Ramdisk data has bad checksum 3022 11 common/image.c Ramdisk data has correct checksum 3023 12 common/image.c Ramdisk verification complete, start loading 3024 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3025 13 common/image.c Start multifile image verification 3026 14 common/image.c No initial ramdisk, no multifile, continue. 3027 3028 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3029 3030 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3031 -31 post/post.c POST test failed, detected by post_output_backlog() 3032 -32 post/post.c POST test failed, detected by post_run_single() 3033 3034 34 common/cmd_doc.c before loading a Image from a DOC device 3035 -35 common/cmd_doc.c Bad usage of "doc" command 3036 35 common/cmd_doc.c correct usage of "doc" command 3037 -36 common/cmd_doc.c No boot device 3038 36 common/cmd_doc.c correct boot device 3039 -37 common/cmd_doc.c Unknown Chip ID on boot device 3040 37 common/cmd_doc.c correct chip ID found, device available 3041 -38 common/cmd_doc.c Read Error on boot device 3042 38 common/cmd_doc.c reading Image header from DOC device OK 3043 -39 common/cmd_doc.c Image header has bad magic number 3044 39 common/cmd_doc.c Image header has correct magic number 3045 -40 common/cmd_doc.c Error reading Image from DOC device 3046 40 common/cmd_doc.c Image header has correct magic number 3047 41 common/cmd_ide.c before loading a Image from a IDE device 3048 -42 common/cmd_ide.c Bad usage of "ide" command 3049 42 common/cmd_ide.c correct usage of "ide" command 3050 -43 common/cmd_ide.c No boot device 3051 43 common/cmd_ide.c boot device found 3052 -44 common/cmd_ide.c Device not available 3053 44 common/cmd_ide.c Device available 3054 -45 common/cmd_ide.c wrong partition selected 3055 45 common/cmd_ide.c partition selected 3056 -46 common/cmd_ide.c Unknown partition table 3057 46 common/cmd_ide.c valid partition table found 3058 -47 common/cmd_ide.c Invalid partition type 3059 47 common/cmd_ide.c correct partition type 3060 -48 common/cmd_ide.c Error reading Image Header on boot device 3061 48 common/cmd_ide.c reading Image Header from IDE device OK 3062 -49 common/cmd_ide.c Image header has bad magic number 3063 49 common/cmd_ide.c Image header has correct magic number 3064 -50 common/cmd_ide.c Image header has bad checksum 3065 50 common/cmd_ide.c Image header has correct checksum 3066 -51 common/cmd_ide.c Error reading Image from IDE device 3067 51 common/cmd_ide.c reading Image from IDE device OK 3068 52 common/cmd_nand.c before loading a Image from a NAND device 3069 -53 common/cmd_nand.c Bad usage of "nand" command 3070 53 common/cmd_nand.c correct usage of "nand" command 3071 -54 common/cmd_nand.c No boot device 3072 54 common/cmd_nand.c boot device found 3073 -55 common/cmd_nand.c Unknown Chip ID on boot device 3074 55 common/cmd_nand.c correct chip ID found, device available 3075 -56 common/cmd_nand.c Error reading Image Header on boot device 3076 56 common/cmd_nand.c reading Image Header from NAND device OK 3077 -57 common/cmd_nand.c Image header has bad magic number 3078 57 common/cmd_nand.c Image header has correct magic number 3079 -58 common/cmd_nand.c Error reading Image from NAND device 3080 58 common/cmd_nand.c reading Image from NAND device OK 3081 3082 -60 common/env_common.c Environment has a bad CRC, using default 3083 3084 64 net/eth.c starting with Ethernet configuration. 3085 -64 net/eth.c no Ethernet found. 3086 65 net/eth.c Ethernet found. 3087 3088 -80 common/cmd_net.c usage wrong 3089 80 common/cmd_net.c before calling NetLoop() 3090 -81 common/cmd_net.c some error in NetLoop() occurred 3091 81 common/cmd_net.c NetLoop() back without error 3092 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3093 82 common/cmd_net.c trying automatic boot 3094 83 common/cmd_net.c running "source" command 3095 -83 common/cmd_net.c some error in automatic boot or "source" command 3096 84 common/cmd_net.c end without errors 3097 3098FIT uImage format: 3099 3100 Arg Where When 3101 100 common/cmd_bootm.c Kernel FIT Image has correct format 3102 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3103 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3104 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3105 102 common/cmd_bootm.c Kernel unit name specified 3106 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3107 103 common/cmd_bootm.c Found configuration node 3108 104 common/cmd_bootm.c Got kernel subimage node offset 3109 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3110 105 common/cmd_bootm.c Kernel subimage hash verification OK 3111 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3112 106 common/cmd_bootm.c Architecture check OK 3113 -106 common/cmd_bootm.c Kernel subimage has wrong type 3114 107 common/cmd_bootm.c Kernel subimage type OK 3115 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3116 108 common/cmd_bootm.c Got kernel subimage data/size 3117 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3118 -109 common/cmd_bootm.c Can't get kernel subimage type 3119 -110 common/cmd_bootm.c Can't get kernel subimage comp 3120 -111 common/cmd_bootm.c Can't get kernel subimage os 3121 -112 common/cmd_bootm.c Can't get kernel subimage load address 3122 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3123 3124 120 common/image.c Start initial ramdisk verification 3125 -120 common/image.c Ramdisk FIT image has incorrect format 3126 121 common/image.c Ramdisk FIT image has correct format 3127 122 common/image.c No ramdisk subimage unit name, using configuration 3128 -122 common/image.c Can't get configuration for ramdisk subimage 3129 123 common/image.c Ramdisk unit name specified 3130 -124 common/image.c Can't get ramdisk subimage node offset 3131 125 common/image.c Got ramdisk subimage node offset 3132 -125 common/image.c Ramdisk subimage hash verification failed 3133 126 common/image.c Ramdisk subimage hash verification OK 3134 -126 common/image.c Ramdisk subimage for unsupported architecture 3135 127 common/image.c Architecture check OK 3136 -127 common/image.c Can't get ramdisk subimage data/size 3137 128 common/image.c Got ramdisk subimage data/size 3138 129 common/image.c Can't get ramdisk load address 3139 -129 common/image.c Got ramdisk load address 3140 3141 -130 common/cmd_doc.c Incorrect FIT image format 3142 131 common/cmd_doc.c FIT image format OK 3143 3144 -140 common/cmd_ide.c Incorrect FIT image format 3145 141 common/cmd_ide.c FIT image format OK 3146 3147 -150 common/cmd_nand.c Incorrect FIT image format 3148 151 common/cmd_nand.c FIT image format OK 3149 3150- FIT image support: 3151 CONFIG_FIT 3152 Enable support for the FIT uImage format. 3153 3154 CONFIG_FIT_BEST_MATCH 3155 When no configuration is explicitly selected, default to the 3156 one whose fdt's compatibility field best matches that of 3157 U-Boot itself. A match is considered "best" if it matches the 3158 most specific compatibility entry of U-Boot's fdt's root node. 3159 The order of entries in the configuration's fdt is ignored. 3160 3161 CONFIG_FIT_SIGNATURE 3162 This option enables signature verification of FIT uImages, 3163 using a hash signed and verified using RSA. See 3164 doc/uImage.FIT/signature.txt for more details. 3165 3166- Standalone program support: 3167 CONFIG_STANDALONE_LOAD_ADDR 3168 3169 This option defines a board specific value for the 3170 address where standalone program gets loaded, thus 3171 overwriting the architecture dependent default 3172 settings. 3173 3174- Frame Buffer Address: 3175 CONFIG_FB_ADDR 3176 3177 Define CONFIG_FB_ADDR if you want to use specific 3178 address for frame buffer. This is typically the case 3179 when using a graphics controller has separate video 3180 memory. U-Boot will then place the frame buffer at 3181 the given address instead of dynamically reserving it 3182 in system RAM by calling lcd_setmem(), which grabs 3183 the memory for the frame buffer depending on the 3184 configured panel size. 3185 3186 Please see board_init_f function. 3187 3188- Automatic software updates via TFTP server 3189 CONFIG_UPDATE_TFTP 3190 CONFIG_UPDATE_TFTP_CNT_MAX 3191 CONFIG_UPDATE_TFTP_MSEC_MAX 3192 3193 These options enable and control the auto-update feature; 3194 for a more detailed description refer to doc/README.update. 3195 3196- MTD Support (mtdparts command, UBI support) 3197 CONFIG_MTD_DEVICE 3198 3199 Adds the MTD device infrastructure from the Linux kernel. 3200 Needed for mtdparts command support. 3201 3202 CONFIG_MTD_PARTITIONS 3203 3204 Adds the MTD partitioning infrastructure from the Linux 3205 kernel. Needed for UBI support. 3206 3207- UBI support 3208 CONFIG_CMD_UBI 3209 3210 Adds commands for interacting with MTD partitions formatted 3211 with the UBI flash translation layer 3212 3213 Requires also defining CONFIG_RBTREE 3214 3215 CONFIG_UBI_SILENCE_MSG 3216 3217 Make the verbose messages from UBI stop printing. This leaves 3218 warnings and errors enabled. 3219 3220- UBIFS support 3221 CONFIG_CMD_UBIFS 3222 3223 Adds commands for interacting with UBI volumes formatted as 3224 UBIFS. UBIFS is read-only in u-boot. 3225 3226 Requires UBI support as well as CONFIG_LZO 3227 3228 CONFIG_UBIFS_SILENCE_MSG 3229 3230 Make the verbose messages from UBIFS stop printing. This leaves 3231 warnings and errors enabled. 3232 3233- SPL framework 3234 CONFIG_SPL 3235 Enable building of SPL globally. 3236 3237 CONFIG_SPL_LDSCRIPT 3238 LDSCRIPT for linking the SPL binary. 3239 3240 CONFIG_SPL_MAX_FOOTPRINT 3241 Maximum size in memory allocated to the SPL, BSS included. 3242 When defined, the linker checks that the actual memory 3243 used by SPL from _start to __bss_end does not exceed it. 3244 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3245 must not be both defined at the same time. 3246 3247 CONFIG_SPL_MAX_SIZE 3248 Maximum size of the SPL image (text, data, rodata, and 3249 linker lists sections), BSS excluded. 3250 When defined, the linker checks that the actual size does 3251 not exceed it. 3252 3253 CONFIG_SPL_TEXT_BASE 3254 TEXT_BASE for linking the SPL binary. 3255 3256 CONFIG_SPL_RELOC_TEXT_BASE 3257 Address to relocate to. If unspecified, this is equal to 3258 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3259 3260 CONFIG_SPL_BSS_START_ADDR 3261 Link address for the BSS within the SPL binary. 3262 3263 CONFIG_SPL_BSS_MAX_SIZE 3264 Maximum size in memory allocated to the SPL BSS. 3265 When defined, the linker checks that the actual memory used 3266 by SPL from __bss_start to __bss_end does not exceed it. 3267 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3268 must not be both defined at the same time. 3269 3270 CONFIG_SPL_STACK 3271 Adress of the start of the stack SPL will use 3272 3273 CONFIG_SPL_RELOC_STACK 3274 Adress of the start of the stack SPL will use after 3275 relocation. If unspecified, this is equal to 3276 CONFIG_SPL_STACK. 3277 3278 CONFIG_SYS_SPL_MALLOC_START 3279 Starting address of the malloc pool used in SPL. 3280 3281 CONFIG_SYS_SPL_MALLOC_SIZE 3282 The size of the malloc pool used in SPL. 3283 3284 CONFIG_SPL_FRAMEWORK 3285 Enable the SPL framework under common/. This framework 3286 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3287 NAND loading of the Linux Kernel. 3288 3289 CONFIG_SPL_OS_BOOT 3290 Enable booting directly to an OS from SPL. 3291 See also: doc/README.falcon 3292 3293 CONFIG_SPL_DISPLAY_PRINT 3294 For ARM, enable an optional function to print more information 3295 about the running system. 3296 3297 CONFIG_SPL_INIT_MINIMAL 3298 Arch init code should be built for a very small image 3299 3300 CONFIG_SPL_LIBCOMMON_SUPPORT 3301 Support for common/libcommon.o in SPL binary 3302 3303 CONFIG_SPL_LIBDISK_SUPPORT 3304 Support for disk/libdisk.o in SPL binary 3305 3306 CONFIG_SPL_I2C_SUPPORT 3307 Support for drivers/i2c/libi2c.o in SPL binary 3308 3309 CONFIG_SPL_GPIO_SUPPORT 3310 Support for drivers/gpio/libgpio.o in SPL binary 3311 3312 CONFIG_SPL_MMC_SUPPORT 3313 Support for drivers/mmc/libmmc.o in SPL binary 3314 3315 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3316 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3317 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION 3318 Address, size and partition on the MMC to load U-Boot from 3319 when the MMC is being used in raw mode. 3320 3321 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3322 Sector to load kernel uImage from when MMC is being 3323 used in raw mode (for Falcon mode) 3324 3325 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3326 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3327 Sector and number of sectors to load kernel argument 3328 parameters from when MMC is being used in raw mode 3329 (for falcon mode) 3330 3331 CONFIG_SPL_FAT_SUPPORT 3332 Support for fs/fat/libfat.o in SPL binary 3333 3334 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME 3335 Filename to read to load U-Boot when reading from FAT 3336 3337 CONFIG_SPL_FAT_LOAD_KERNEL_NAME 3338 Filename to read to load kernel uImage when reading 3339 from FAT (for Falcon mode) 3340 3341 CONFIG_SPL_FAT_LOAD_ARGS_NAME 3342 Filename to read to load kernel argument parameters 3343 when reading from FAT (for Falcon mode) 3344 3345 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3346 Set this for NAND SPL on PPC mpc83xx targets, so that 3347 start.S waits for the rest of the SPL to load before 3348 continuing (the hardware starts execution after just 3349 loading the first page rather than the full 4K). 3350 3351 CONFIG_SPL_SKIP_RELOCATE 3352 Avoid SPL relocation 3353 3354 CONFIG_SPL_NAND_BASE 3355 Include nand_base.c in the SPL. Requires 3356 CONFIG_SPL_NAND_DRIVERS. 3357 3358 CONFIG_SPL_NAND_DRIVERS 3359 SPL uses normal NAND drivers, not minimal drivers. 3360 3361 CONFIG_SPL_NAND_ECC 3362 Include standard software ECC in the SPL 3363 3364 CONFIG_SPL_NAND_SIMPLE 3365 Support for NAND boot using simple NAND drivers that 3366 expose the cmd_ctrl() interface. 3367 3368 CONFIG_SPL_MTD_SUPPORT 3369 Support for the MTD subsystem within SPL. Useful for 3370 environment on NAND support within SPL. 3371 3372 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3373 Set for the SPL on PPC mpc8xxx targets, support for 3374 drivers/ddr/fsl/libddr.o in SPL binary. 3375 3376 CONFIG_SPL_COMMON_INIT_DDR 3377 Set for common ddr init with serial presence detect in 3378 SPL binary. 3379 3380 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3381 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3382 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3383 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3384 CONFIG_SYS_NAND_ECCBYTES 3385 Defines the size and behavior of the NAND that SPL uses 3386 to read U-Boot 3387 3388 CONFIG_SPL_NAND_BOOT 3389 Add support NAND boot 3390 3391 CONFIG_SYS_NAND_U_BOOT_OFFS 3392 Location in NAND to read U-Boot from 3393 3394 CONFIG_SYS_NAND_U_BOOT_DST 3395 Location in memory to load U-Boot to 3396 3397 CONFIG_SYS_NAND_U_BOOT_SIZE 3398 Size of image to load 3399 3400 CONFIG_SYS_NAND_U_BOOT_START 3401 Entry point in loaded image to jump to 3402 3403 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3404 Define this if you need to first read the OOB and then the 3405 data. This is used for example on davinci plattforms. 3406 3407 CONFIG_SPL_OMAP3_ID_NAND 3408 Support for an OMAP3-specific set of functions to return the 3409 ID and MFR of the first attached NAND chip, if present. 3410 3411 CONFIG_SPL_SERIAL_SUPPORT 3412 Support for drivers/serial/libserial.o in SPL binary 3413 3414 CONFIG_SPL_SPI_FLASH_SUPPORT 3415 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3416 3417 CONFIG_SPL_SPI_SUPPORT 3418 Support for drivers/spi/libspi.o in SPL binary 3419 3420 CONFIG_SPL_RAM_DEVICE 3421 Support for running image already present in ram, in SPL binary 3422 3423 CONFIG_SPL_LIBGENERIC_SUPPORT 3424 Support for lib/libgeneric.o in SPL binary 3425 3426 CONFIG_SPL_ENV_SUPPORT 3427 Support for the environment operating in SPL binary 3428 3429 CONFIG_SPL_NET_SUPPORT 3430 Support for the net/libnet.o in SPL binary. 3431 It conflicts with SPL env from storage medium specified by 3432 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3433 3434 CONFIG_SPL_PAD_TO 3435 Image offset to which the SPL should be padded before appending 3436 the SPL payload. By default, this is defined as 3437 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3438 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3439 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3440 3441 CONFIG_SPL_TARGET 3442 Final target image containing SPL and payload. Some SPLs 3443 use an arch-specific makefile fragment instead, for 3444 example if more than one image needs to be produced. 3445 3446 CONFIG_FIT_SPL_PRINT 3447 Printing information about a FIT image adds quite a bit of 3448 code to SPL. So this is normally disabled in SPL. Use this 3449 option to re-enable it. This will affect the output of the 3450 bootm command when booting a FIT image. 3451 3452- TPL framework 3453 CONFIG_TPL 3454 Enable building of TPL globally. 3455 3456 CONFIG_TPL_PAD_TO 3457 Image offset to which the TPL should be padded before appending 3458 the TPL payload. By default, this is defined as 3459 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3460 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3461 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3462 3463Modem Support: 3464-------------- 3465 3466[so far only for SMDK2400 boards] 3467 3468- Modem support enable: 3469 CONFIG_MODEM_SUPPORT 3470 3471- RTS/CTS Flow control enable: 3472 CONFIG_HWFLOW 3473 3474- Modem debug support: 3475 CONFIG_MODEM_SUPPORT_DEBUG 3476 3477 Enables debugging stuff (char screen[1024], dbg()) 3478 for modem support. Useful only with BDI2000. 3479 3480- Interrupt support (PPC): 3481 3482 There are common interrupt_init() and timer_interrupt() 3483 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3484 for CPU specific initialization. interrupt_init_cpu() 3485 should set decrementer_count to appropriate value. If 3486 CPU resets decrementer automatically after interrupt 3487 (ppc4xx) it should set decrementer_count to zero. 3488 timer_interrupt() calls timer_interrupt_cpu() for CPU 3489 specific handling. If board has watchdog / status_led 3490 / other_activity_monitor it works automatically from 3491 general timer_interrupt(). 3492 3493- General: 3494 3495 In the target system modem support is enabled when a 3496 specific key (key combination) is pressed during 3497 power-on. Otherwise U-Boot will boot normally 3498 (autoboot). The key_pressed() function is called from 3499 board_init(). Currently key_pressed() is a dummy 3500 function, returning 1 and thus enabling modem 3501 initialization. 3502 3503 If there are no modem init strings in the 3504 environment, U-Boot proceed to autoboot; the 3505 previous output (banner, info printfs) will be 3506 suppressed, though. 3507 3508 See also: doc/README.Modem 3509 3510Board initialization settings: 3511------------------------------ 3512 3513During Initialization u-boot calls a number of board specific functions 3514to allow the preparation of board specific prerequisites, e.g. pin setup 3515before drivers are initialized. To enable these callbacks the 3516following configuration macros have to be defined. Currently this is 3517architecture specific, so please check arch/your_architecture/lib/board.c 3518typically in board_init_f() and board_init_r(). 3519 3520- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3521- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3522- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3523- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3524 3525Configuration Settings: 3526----------------------- 3527 3528- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3529 Optionally it can be defined to support 64-bit memory commands. 3530 3531- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3532 undefine this when you're short of memory. 3533 3534- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3535 width of the commands listed in the 'help' command output. 3536 3537- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3538 prompt for user input. 3539 3540- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3541 3542- CONFIG_SYS_PBSIZE: Buffer size for Console output 3543 3544- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3545 3546- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3547 the application (usually a Linux kernel) when it is 3548 booted 3549 3550- CONFIG_SYS_BAUDRATE_TABLE: 3551 List of legal baudrate settings for this board. 3552 3553- CONFIG_SYS_CONSOLE_INFO_QUIET 3554 Suppress display of console information at boot. 3555 3556- CONFIG_SYS_CONSOLE_IS_IN_ENV 3557 If the board specific function 3558 extern int overwrite_console (void); 3559 returns 1, the stdin, stderr and stdout are switched to the 3560 serial port, else the settings in the environment are used. 3561 3562- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3563 Enable the call to overwrite_console(). 3564 3565- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3566 Enable overwrite of previous console environment settings. 3567 3568- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3569 Begin and End addresses of the area used by the 3570 simple memory test. 3571 3572- CONFIG_SYS_ALT_MEMTEST: 3573 Enable an alternate, more extensive memory test. 3574 3575- CONFIG_SYS_MEMTEST_SCRATCH: 3576 Scratch address used by the alternate memory test 3577 You only need to set this if address zero isn't writeable 3578 3579- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3580 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3581 this specified memory area will get subtracted from the top 3582 (end) of RAM and won't get "touched" at all by U-Boot. By 3583 fixing up gd->ram_size the Linux kernel should gets passed 3584 the now "corrected" memory size and won't touch it either. 3585 This should work for arch/ppc and arch/powerpc. Only Linux 3586 board ports in arch/powerpc with bootwrapper support that 3587 recalculate the memory size from the SDRAM controller setup 3588 will have to get fixed in Linux additionally. 3589 3590 This option can be used as a workaround for the 440EPx/GRx 3591 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3592 be touched. 3593 3594 WARNING: Please make sure that this value is a multiple of 3595 the Linux page size (normally 4k). If this is not the case, 3596 then the end address of the Linux memory will be located at a 3597 non page size aligned address and this could cause major 3598 problems. 3599 3600- CONFIG_SYS_LOADS_BAUD_CHANGE: 3601 Enable temporary baudrate change while serial download 3602 3603- CONFIG_SYS_SDRAM_BASE: 3604 Physical start address of SDRAM. _Must_ be 0 here. 3605 3606- CONFIG_SYS_MBIO_BASE: 3607 Physical start address of Motherboard I/O (if using a 3608 Cogent motherboard) 3609 3610- CONFIG_SYS_FLASH_BASE: 3611 Physical start address of Flash memory. 3612 3613- CONFIG_SYS_MONITOR_BASE: 3614 Physical start address of boot monitor code (set by 3615 make config files to be same as the text base address 3616 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3617 CONFIG_SYS_FLASH_BASE when booting from flash. 3618 3619- CONFIG_SYS_MONITOR_LEN: 3620 Size of memory reserved for monitor code, used to 3621 determine _at_compile_time_ (!) if the environment is 3622 embedded within the U-Boot image, or in a separate 3623 flash sector. 3624 3625- CONFIG_SYS_MALLOC_LEN: 3626 Size of DRAM reserved for malloc() use. 3627 3628- CONFIG_SYS_BOOTM_LEN: 3629 Normally compressed uImages are limited to an 3630 uncompressed size of 8 MBytes. If this is not enough, 3631 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3632 to adjust this setting to your needs. 3633 3634- CONFIG_SYS_BOOTMAPSZ: 3635 Maximum size of memory mapped by the startup code of 3636 the Linux kernel; all data that must be processed by 3637 the Linux kernel (bd_info, boot arguments, FDT blob if 3638 used) must be put below this limit, unless "bootm_low" 3639 environment variable is defined and non-zero. In such case 3640 all data for the Linux kernel must be between "bootm_low" 3641 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3642 variable "bootm_mapsize" will override the value of 3643 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3644 then the value in "bootm_size" will be used instead. 3645 3646- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3647 Enable initrd_high functionality. If defined then the 3648 initrd_high feature is enabled and the bootm ramdisk subcommand 3649 is enabled. 3650 3651- CONFIG_SYS_BOOT_GET_CMDLINE: 3652 Enables allocating and saving kernel cmdline in space between 3653 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3654 3655- CONFIG_SYS_BOOT_GET_KBD: 3656 Enables allocating and saving a kernel copy of the bd_info in 3657 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3658 3659- CONFIG_SYS_MAX_FLASH_BANKS: 3660 Max number of Flash memory banks 3661 3662- CONFIG_SYS_MAX_FLASH_SECT: 3663 Max number of sectors on a Flash chip 3664 3665- CONFIG_SYS_FLASH_ERASE_TOUT: 3666 Timeout for Flash erase operations (in ms) 3667 3668- CONFIG_SYS_FLASH_WRITE_TOUT: 3669 Timeout for Flash write operations (in ms) 3670 3671- CONFIG_SYS_FLASH_LOCK_TOUT 3672 Timeout for Flash set sector lock bit operation (in ms) 3673 3674- CONFIG_SYS_FLASH_UNLOCK_TOUT 3675 Timeout for Flash clear lock bits operation (in ms) 3676 3677- CONFIG_SYS_FLASH_PROTECTION 3678 If defined, hardware flash sectors protection is used 3679 instead of U-Boot software protection. 3680 3681- CONFIG_SYS_DIRECT_FLASH_TFTP: 3682 3683 Enable TFTP transfers directly to flash memory; 3684 without this option such a download has to be 3685 performed in two steps: (1) download to RAM, and (2) 3686 copy from RAM to flash. 3687 3688 The two-step approach is usually more reliable, since 3689 you can check if the download worked before you erase 3690 the flash, but in some situations (when system RAM is 3691 too limited to allow for a temporary copy of the 3692 downloaded image) this option may be very useful. 3693 3694- CONFIG_SYS_FLASH_CFI: 3695 Define if the flash driver uses extra elements in the 3696 common flash structure for storing flash geometry. 3697 3698- CONFIG_FLASH_CFI_DRIVER 3699 This option also enables the building of the cfi_flash driver 3700 in the drivers directory 3701 3702- CONFIG_FLASH_CFI_MTD 3703 This option enables the building of the cfi_mtd driver 3704 in the drivers directory. The driver exports CFI flash 3705 to the MTD layer. 3706 3707- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3708 Use buffered writes to flash. 3709 3710- CONFIG_FLASH_SPANSION_S29WS_N 3711 s29ws-n MirrorBit flash has non-standard addresses for buffered 3712 write commands. 3713 3714- CONFIG_SYS_FLASH_QUIET_TEST 3715 If this option is defined, the common CFI flash doesn't 3716 print it's warning upon not recognized FLASH banks. This 3717 is useful, if some of the configured banks are only 3718 optionally available. 3719 3720- CONFIG_FLASH_SHOW_PROGRESS 3721 If defined (must be an integer), print out countdown 3722 digits and dots. Recommended value: 45 (9..1) for 80 3723 column displays, 15 (3..1) for 40 column displays. 3724 3725- CONFIG_FLASH_VERIFY 3726 If defined, the content of the flash (destination) is compared 3727 against the source after the write operation. An error message 3728 will be printed when the contents are not identical. 3729 Please note that this option is useless in nearly all cases, 3730 since such flash programming errors usually are detected earlier 3731 while unprotecting/erasing/programming. Please only enable 3732 this option if you really know what you are doing. 3733 3734- CONFIG_SYS_RX_ETH_BUFFER: 3735 Defines the number of Ethernet receive buffers. On some 3736 Ethernet controllers it is recommended to set this value 3737 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3738 buffers can be full shortly after enabling the interface 3739 on high Ethernet traffic. 3740 Defaults to 4 if not defined. 3741 3742- CONFIG_ENV_MAX_ENTRIES 3743 3744 Maximum number of entries in the hash table that is used 3745 internally to store the environment settings. The default 3746 setting is supposed to be generous and should work in most 3747 cases. This setting can be used to tune behaviour; see 3748 lib/hashtable.c for details. 3749 3750- CONFIG_ENV_FLAGS_LIST_DEFAULT 3751- CONFIG_ENV_FLAGS_LIST_STATIC 3752 Enable validation of the values given to environment variables when 3753 calling env set. Variables can be restricted to only decimal, 3754 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3755 the variables can also be restricted to IP address or MAC address. 3756 3757 The format of the list is: 3758 type_attribute = [s|d|x|b|i|m] 3759 access_atribute = [a|r|o|c] 3760 attributes = type_attribute[access_atribute] 3761 entry = variable_name[:attributes] 3762 list = entry[,list] 3763 3764 The type attributes are: 3765 s - String (default) 3766 d - Decimal 3767 x - Hexadecimal 3768 b - Boolean ([1yYtT|0nNfF]) 3769 i - IP address 3770 m - MAC address 3771 3772 The access attributes are: 3773 a - Any (default) 3774 r - Read-only 3775 o - Write-once 3776 c - Change-default 3777 3778 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3779 Define this to a list (string) to define the ".flags" 3780 envirnoment variable in the default or embedded environment. 3781 3782 - CONFIG_ENV_FLAGS_LIST_STATIC 3783 Define this to a list (string) to define validation that 3784 should be done if an entry is not found in the ".flags" 3785 environment variable. To override a setting in the static 3786 list, simply add an entry for the same variable name to the 3787 ".flags" variable. 3788 3789- CONFIG_ENV_ACCESS_IGNORE_FORCE 3790 If defined, don't allow the -f switch to env set override variable 3791 access flags. 3792 3793- CONFIG_SYS_GENERIC_BOARD 3794 This selects the architecture-generic board system instead of the 3795 architecture-specific board files. It is intended to move boards 3796 to this new framework over time. Defining this will disable the 3797 arch/foo/lib/board.c file and use common/board_f.c and 3798 common/board_r.c instead. To use this option your architecture 3799 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in 3800 its config.mk file). If you find problems enabling this option on 3801 your board please report the problem and send patches! 3802 3803- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 3804 This is set by OMAP boards for the max time that reset should 3805 be asserted. See doc/README.omap-reset-time for details on how 3806 the value can be calulated on a given board. 3807 3808The following definitions that deal with the placement and management 3809of environment data (variable area); in general, we support the 3810following configurations: 3811 3812- CONFIG_BUILD_ENVCRC: 3813 3814 Builds up envcrc with the target environment so that external utils 3815 may easily extract it and embed it in final U-Boot images. 3816 3817- CONFIG_ENV_IS_IN_FLASH: 3818 3819 Define this if the environment is in flash memory. 3820 3821 a) The environment occupies one whole flash sector, which is 3822 "embedded" in the text segment with the U-Boot code. This 3823 happens usually with "bottom boot sector" or "top boot 3824 sector" type flash chips, which have several smaller 3825 sectors at the start or the end. For instance, such a 3826 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3827 such a case you would place the environment in one of the 3828 4 kB sectors - with U-Boot code before and after it. With 3829 "top boot sector" type flash chips, you would put the 3830 environment in one of the last sectors, leaving a gap 3831 between U-Boot and the environment. 3832 3833 - CONFIG_ENV_OFFSET: 3834 3835 Offset of environment data (variable area) to the 3836 beginning of flash memory; for instance, with bottom boot 3837 type flash chips the second sector can be used: the offset 3838 for this sector is given here. 3839 3840 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3841 3842 - CONFIG_ENV_ADDR: 3843 3844 This is just another way to specify the start address of 3845 the flash sector containing the environment (instead of 3846 CONFIG_ENV_OFFSET). 3847 3848 - CONFIG_ENV_SECT_SIZE: 3849 3850 Size of the sector containing the environment. 3851 3852 3853 b) Sometimes flash chips have few, equal sized, BIG sectors. 3854 In such a case you don't want to spend a whole sector for 3855 the environment. 3856 3857 - CONFIG_ENV_SIZE: 3858 3859 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3860 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3861 of this flash sector for the environment. This saves 3862 memory for the RAM copy of the environment. 3863 3864 It may also save flash memory if you decide to use this 3865 when your environment is "embedded" within U-Boot code, 3866 since then the remainder of the flash sector could be used 3867 for U-Boot code. It should be pointed out that this is 3868 STRONGLY DISCOURAGED from a robustness point of view: 3869 updating the environment in flash makes it always 3870 necessary to erase the WHOLE sector. If something goes 3871 wrong before the contents has been restored from a copy in 3872 RAM, your target system will be dead. 3873 3874 - CONFIG_ENV_ADDR_REDUND 3875 CONFIG_ENV_SIZE_REDUND 3876 3877 These settings describe a second storage area used to hold 3878 a redundant copy of the environment data, so that there is 3879 a valid backup copy in case there is a power failure during 3880 a "saveenv" operation. 3881 3882BE CAREFUL! Any changes to the flash layout, and some changes to the 3883source code will make it necessary to adapt <board>/u-boot.lds* 3884accordingly! 3885 3886 3887- CONFIG_ENV_IS_IN_NVRAM: 3888 3889 Define this if you have some non-volatile memory device 3890 (NVRAM, battery buffered SRAM) which you want to use for the 3891 environment. 3892 3893 - CONFIG_ENV_ADDR: 3894 - CONFIG_ENV_SIZE: 3895 3896 These two #defines are used to determine the memory area you 3897 want to use for environment. It is assumed that this memory 3898 can just be read and written to, without any special 3899 provision. 3900 3901BE CAREFUL! The first access to the environment happens quite early 3902in U-Boot initalization (when we try to get the setting of for the 3903console baudrate). You *MUST* have mapped your NVRAM area then, or 3904U-Boot will hang. 3905 3906Please note that even with NVRAM we still use a copy of the 3907environment in RAM: we could work on NVRAM directly, but we want to 3908keep settings there always unmodified except somebody uses "saveenv" 3909to save the current settings. 3910 3911 3912- CONFIG_ENV_IS_IN_EEPROM: 3913 3914 Use this if you have an EEPROM or similar serial access 3915 device and a driver for it. 3916 3917 - CONFIG_ENV_OFFSET: 3918 - CONFIG_ENV_SIZE: 3919 3920 These two #defines specify the offset and size of the 3921 environment area within the total memory of your EEPROM. 3922 3923 - CONFIG_SYS_I2C_EEPROM_ADDR: 3924 If defined, specified the chip address of the EEPROM device. 3925 The default address is zero. 3926 3927 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3928 If defined, the number of bits used to address bytes in a 3929 single page in the EEPROM device. A 64 byte page, for example 3930 would require six bits. 3931 3932 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3933 If defined, the number of milliseconds to delay between 3934 page writes. The default is zero milliseconds. 3935 3936 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3937 The length in bytes of the EEPROM memory array address. Note 3938 that this is NOT the chip address length! 3939 3940 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3941 EEPROM chips that implement "address overflow" are ones 3942 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3943 address and the extra bits end up in the "chip address" bit 3944 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3945 byte chips. 3946 3947 Note that we consider the length of the address field to 3948 still be one byte because the extra address bits are hidden 3949 in the chip address. 3950 3951 - CONFIG_SYS_EEPROM_SIZE: 3952 The size in bytes of the EEPROM device. 3953 3954 - CONFIG_ENV_EEPROM_IS_ON_I2C 3955 define this, if you have I2C and SPI activated, and your 3956 EEPROM, which holds the environment, is on the I2C bus. 3957 3958 - CONFIG_I2C_ENV_EEPROM_BUS 3959 if you have an Environment on an EEPROM reached over 3960 I2C muxes, you can define here, how to reach this 3961 EEPROM. For example: 3962 3963 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3964 3965 EEPROM which holds the environment, is reached over 3966 a pca9547 i2c mux with address 0x70, channel 3. 3967 3968- CONFIG_ENV_IS_IN_DATAFLASH: 3969 3970 Define this if you have a DataFlash memory device which you 3971 want to use for the environment. 3972 3973 - CONFIG_ENV_OFFSET: 3974 - CONFIG_ENV_ADDR: 3975 - CONFIG_ENV_SIZE: 3976 3977 These three #defines specify the offset and size of the 3978 environment area within the total memory of your DataFlash placed 3979 at the specified address. 3980 3981- CONFIG_ENV_IS_IN_REMOTE: 3982 3983 Define this if you have a remote memory space which you 3984 want to use for the local device's environment. 3985 3986 - CONFIG_ENV_ADDR: 3987 - CONFIG_ENV_SIZE: 3988 3989 These two #defines specify the address and size of the 3990 environment area within the remote memory space. The 3991 local device can get the environment from remote memory 3992 space by SRIO or PCIE links. 3993 3994BE CAREFUL! For some special cases, the local device can not use 3995"saveenv" command. For example, the local device will get the 3996environment stored in a remote NOR flash by SRIO or PCIE link, 3997but it can not erase, write this NOR flash by SRIO or PCIE interface. 3998 3999- CONFIG_ENV_IS_IN_NAND: 4000 4001 Define this if you have a NAND device which you want to use 4002 for the environment. 4003 4004 - CONFIG_ENV_OFFSET: 4005 - CONFIG_ENV_SIZE: 4006 4007 These two #defines specify the offset and size of the environment 4008 area within the first NAND device. CONFIG_ENV_OFFSET must be 4009 aligned to an erase block boundary. 4010 4011 - CONFIG_ENV_OFFSET_REDUND (optional): 4012 4013 This setting describes a second storage area of CONFIG_ENV_SIZE 4014 size used to hold a redundant copy of the environment data, so 4015 that there is a valid backup copy in case there is a power failure 4016 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4017 aligned to an erase block boundary. 4018 4019 - CONFIG_ENV_RANGE (optional): 4020 4021 Specifies the length of the region in which the environment 4022 can be written. This should be a multiple of the NAND device's 4023 block size. Specifying a range with more erase blocks than 4024 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4025 the range to be avoided. 4026 4027 - CONFIG_ENV_OFFSET_OOB (optional): 4028 4029 Enables support for dynamically retrieving the offset of the 4030 environment from block zero's out-of-band data. The 4031 "nand env.oob" command can be used to record this offset. 4032 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4033 using CONFIG_ENV_OFFSET_OOB. 4034 4035- CONFIG_NAND_ENV_DST 4036 4037 Defines address in RAM to which the nand_spl code should copy the 4038 environment. If redundant environment is used, it will be copied to 4039 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4040 4041- CONFIG_ENV_IS_IN_UBI: 4042 4043 Define this if you have an UBI volume that you want to use for the 4044 environment. This has the benefit of wear-leveling the environment 4045 accesses, which is important on NAND. 4046 4047 - CONFIG_ENV_UBI_PART: 4048 4049 Define this to a string that is the mtd partition containing the UBI. 4050 4051 - CONFIG_ENV_UBI_VOLUME: 4052 4053 Define this to the name of the volume that you want to store the 4054 environment in. 4055 4056 - CONFIG_ENV_UBI_VOLUME_REDUND: 4057 4058 Define this to the name of another volume to store a second copy of 4059 the environment in. This will enable redundant environments in UBI. 4060 It is assumed that both volumes are in the same MTD partition. 4061 4062 - CONFIG_UBI_SILENCE_MSG 4063 - CONFIG_UBIFS_SILENCE_MSG 4064 4065 You will probably want to define these to avoid a really noisy system 4066 when storing the env in UBI. 4067 4068- CONFIG_ENV_IS_IN_MMC: 4069 4070 Define this if you have an MMC device which you want to use for the 4071 environment. 4072 4073 - CONFIG_SYS_MMC_ENV_DEV: 4074 4075 Specifies which MMC device the environment is stored in. 4076 4077 - CONFIG_SYS_MMC_ENV_PART (optional): 4078 4079 Specifies which MMC partition the environment is stored in. If not 4080 set, defaults to partition 0, the user area. Common values might be 4081 1 (first MMC boot partition), 2 (second MMC boot partition). 4082 4083 - CONFIG_ENV_OFFSET: 4084 - CONFIG_ENV_SIZE: 4085 4086 These two #defines specify the offset and size of the environment 4087 area within the specified MMC device. 4088 4089 If offset is positive (the usual case), it is treated as relative to 4090 the start of the MMC partition. If offset is negative, it is treated 4091 as relative to the end of the MMC partition. This can be useful if 4092 your board may be fitted with different MMC devices, which have 4093 different sizes for the MMC partitions, and you always want the 4094 environment placed at the very end of the partition, to leave the 4095 maximum possible space before it, to store other data. 4096 4097 These two values are in units of bytes, but must be aligned to an 4098 MMC sector boundary. 4099 4100 - CONFIG_ENV_OFFSET_REDUND (optional): 4101 4102 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4103 hold a redundant copy of the environment data. This provides a 4104 valid backup copy in case the other copy is corrupted, e.g. due 4105 to a power failure during a "saveenv" operation. 4106 4107 This value may also be positive or negative; this is handled in the 4108 same way as CONFIG_ENV_OFFSET. 4109 4110 This value is also in units of bytes, but must also be aligned to 4111 an MMC sector boundary. 4112 4113 - CONFIG_ENV_SIZE_REDUND (optional): 4114 4115 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4116 set. If this value is set, it must be set to the same value as 4117 CONFIG_ENV_SIZE. 4118 4119- CONFIG_SYS_SPI_INIT_OFFSET 4120 4121 Defines offset to the initial SPI buffer area in DPRAM. The 4122 area is used at an early stage (ROM part) if the environment 4123 is configured to reside in the SPI EEPROM: We need a 520 byte 4124 scratch DPRAM area. It is used between the two initialization 4125 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4126 to be a good choice since it makes it far enough from the 4127 start of the data area as well as from the stack pointer. 4128 4129Please note that the environment is read-only until the monitor 4130has been relocated to RAM and a RAM copy of the environment has been 4131created; also, when using EEPROM you will have to use getenv_f() 4132until then to read environment variables. 4133 4134The environment is protected by a CRC32 checksum. Before the monitor 4135is relocated into RAM, as a result of a bad CRC you will be working 4136with the compiled-in default environment - *silently*!!! [This is 4137necessary, because the first environment variable we need is the 4138"baudrate" setting for the console - if we have a bad CRC, we don't 4139have any device yet where we could complain.] 4140 4141Note: once the monitor has been relocated, then it will complain if 4142the default environment is used; a new CRC is computed as soon as you 4143use the "saveenv" command to store a valid environment. 4144 4145- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4146 Echo the inverted Ethernet link state to the fault LED. 4147 4148 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4149 also needs to be defined. 4150 4151- CONFIG_SYS_FAULT_MII_ADDR: 4152 MII address of the PHY to check for the Ethernet link state. 4153 4154- CONFIG_NS16550_MIN_FUNCTIONS: 4155 Define this if you desire to only have use of the NS16550_init 4156 and NS16550_putc functions for the serial driver located at 4157 drivers/serial/ns16550.c. This option is useful for saving 4158 space for already greatly restricted images, including but not 4159 limited to NAND_SPL configurations. 4160 4161- CONFIG_DISPLAY_BOARDINFO 4162 Display information about the board that U-Boot is running on 4163 when U-Boot starts up. The board function checkboard() is called 4164 to do this. 4165 4166- CONFIG_DISPLAY_BOARDINFO_LATE 4167 Similar to the previous option, but display this information 4168 later, once stdio is running and output goes to the LCD, if 4169 present. 4170 4171Low Level (hardware related) configuration options: 4172--------------------------------------------------- 4173 4174- CONFIG_SYS_CACHELINE_SIZE: 4175 Cache Line Size of the CPU. 4176 4177- CONFIG_SYS_DEFAULT_IMMR: 4178 Default address of the IMMR after system reset. 4179 4180 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4181 and RPXsuper) to be able to adjust the position of 4182 the IMMR register after a reset. 4183 4184- CONFIG_SYS_CCSRBAR_DEFAULT: 4185 Default (power-on reset) physical address of CCSR on Freescale 4186 PowerPC SOCs. 4187 4188- CONFIG_SYS_CCSRBAR: 4189 Virtual address of CCSR. On a 32-bit build, this is typically 4190 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4191 4192 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4193 for cross-platform code that uses that macro instead. 4194 4195- CONFIG_SYS_CCSRBAR_PHYS: 4196 Physical address of CCSR. CCSR can be relocated to a new 4197 physical address, if desired. In this case, this macro should 4198 be set to that address. Otherwise, it should be set to the 4199 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4200 is typically relocated on 36-bit builds. It is recommended 4201 that this macro be defined via the _HIGH and _LOW macros: 4202 4203 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4204 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4205 4206- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4207 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4208 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4209 used in assembly code, so it must not contain typecasts or 4210 integer size suffixes (e.g. "ULL"). 4211 4212- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4213 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4214 used in assembly code, so it must not contain typecasts or 4215 integer size suffixes (e.g. "ULL"). 4216 4217- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4218 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4219 forced to a value that ensures that CCSR is not relocated. 4220 4221- Floppy Disk Support: 4222 CONFIG_SYS_FDC_DRIVE_NUMBER 4223 4224 the default drive number (default value 0) 4225 4226 CONFIG_SYS_ISA_IO_STRIDE 4227 4228 defines the spacing between FDC chipset registers 4229 (default value 1) 4230 4231 CONFIG_SYS_ISA_IO_OFFSET 4232 4233 defines the offset of register from address. It 4234 depends on which part of the data bus is connected to 4235 the FDC chipset. (default value 0) 4236 4237 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4238 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4239 default value. 4240 4241 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4242 fdc_hw_init() is called at the beginning of the FDC 4243 setup. fdc_hw_init() must be provided by the board 4244 source code. It is used to make hardware dependant 4245 initializations. 4246 4247- CONFIG_IDE_AHB: 4248 Most IDE controllers were designed to be connected with PCI 4249 interface. Only few of them were designed for AHB interface. 4250 When software is doing ATA command and data transfer to 4251 IDE devices through IDE-AHB controller, some additional 4252 registers accessing to these kind of IDE-AHB controller 4253 is requierd. 4254 4255- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4256 DO NOT CHANGE unless you know exactly what you're 4257 doing! (11-4) [MPC8xx/82xx systems only] 4258 4259- CONFIG_SYS_INIT_RAM_ADDR: 4260 4261 Start address of memory area that can be used for 4262 initial data and stack; please note that this must be 4263 writable memory that is working WITHOUT special 4264 initialization, i. e. you CANNOT use normal RAM which 4265 will become available only after programming the 4266 memory controller and running certain initialization 4267 sequences. 4268 4269 U-Boot uses the following memory types: 4270 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4271 - MPC824X: data cache 4272 - PPC4xx: data cache 4273 4274- CONFIG_SYS_GBL_DATA_OFFSET: 4275 4276 Offset of the initial data structure in the memory 4277 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4278 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4279 data is located at the end of the available space 4280 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4281 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4282 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4283 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4284 4285 Note: 4286 On the MPC824X (or other systems that use the data 4287 cache for initial memory) the address chosen for 4288 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4289 point to an otherwise UNUSED address space between 4290 the top of RAM and the start of the PCI space. 4291 4292- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4293 4294- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4295 4296- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4297 4298- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4299 4300- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4301 4302- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4303 4304- CONFIG_SYS_OR_TIMING_SDRAM: 4305 SDRAM timing 4306 4307- CONFIG_SYS_MAMR_PTA: 4308 periodic timer for refresh 4309 4310- CONFIG_SYS_DER: Debug Event Register (37-47) 4311 4312- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4313 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4314 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4315 CONFIG_SYS_BR1_PRELIM: 4316 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4317 4318- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4319 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4320 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4321 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4322 4323- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4324 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4325 Machine Mode Register and Memory Periodic Timer 4326 Prescaler definitions (SDRAM timing) 4327 4328- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4329 enable I2C microcode relocation patch (MPC8xx); 4330 define relocation offset in DPRAM [DSP2] 4331 4332- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4333 enable SMC microcode relocation patch (MPC8xx); 4334 define relocation offset in DPRAM [SMC1] 4335 4336- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4337 enable SPI microcode relocation patch (MPC8xx); 4338 define relocation offset in DPRAM [SCC4] 4339 4340- CONFIG_SYS_USE_OSCCLK: 4341 Use OSCM clock mode on MBX8xx board. Be careful, 4342 wrong setting might damage your board. Read 4343 doc/README.MBX before setting this variable! 4344 4345- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4346 Offset of the bootmode word in DPRAM used by post 4347 (Power On Self Tests). This definition overrides 4348 #define'd default value in commproc.h resp. 4349 cpm_8260.h. 4350 4351- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4352 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4353 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4354 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4355 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4356 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4357 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4358 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4359 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4360 4361- CONFIG_PCI_DISABLE_PCIE: 4362 Disable PCI-Express on systems where it is supported but not 4363 required. 4364 4365- CONFIG_PCI_ENUM_ONLY 4366 Only scan through and get the devices on the busses. 4367 Don't do any setup work, presumably because someone or 4368 something has already done it, and we don't need to do it 4369 a second time. Useful for platforms that are pre-booted 4370 by coreboot or similar. 4371 4372- CONFIG_PCI_INDIRECT_BRIDGE: 4373 Enable support for indirect PCI bridges. 4374 4375- CONFIG_SYS_SRIO: 4376 Chip has SRIO or not 4377 4378- CONFIG_SRIO1: 4379 Board has SRIO 1 port available 4380 4381- CONFIG_SRIO2: 4382 Board has SRIO 2 port available 4383 4384- CONFIG_SRIO_PCIE_BOOT_MASTER 4385 Board can support master function for Boot from SRIO and PCIE 4386 4387- CONFIG_SYS_SRIOn_MEM_VIRT: 4388 Virtual Address of SRIO port 'n' memory region 4389 4390- CONFIG_SYS_SRIOn_MEM_PHYS: 4391 Physical Address of SRIO port 'n' memory region 4392 4393- CONFIG_SYS_SRIOn_MEM_SIZE: 4394 Size of SRIO port 'n' memory region 4395 4396- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4397 Defined to tell the NAND controller that the NAND chip is using 4398 a 16 bit bus. 4399 Not all NAND drivers use this symbol. 4400 Example of drivers that use it: 4401 - drivers/mtd/nand/ndfc.c 4402 - drivers/mtd/nand/mxc_nand.c 4403 4404- CONFIG_SYS_NDFC_EBC0_CFG 4405 Sets the EBC0_CFG register for the NDFC. If not defined 4406 a default value will be used. 4407 4408- CONFIG_SPD_EEPROM 4409 Get DDR timing information from an I2C EEPROM. Common 4410 with pluggable memory modules such as SODIMMs 4411 4412 SPD_EEPROM_ADDRESS 4413 I2C address of the SPD EEPROM 4414 4415- CONFIG_SYS_SPD_BUS_NUM 4416 If SPD EEPROM is on an I2C bus other than the first 4417 one, specify here. Note that the value must resolve 4418 to something your driver can deal with. 4419 4420- CONFIG_SYS_DDR_RAW_TIMING 4421 Get DDR timing information from other than SPD. Common with 4422 soldered DDR chips onboard without SPD. DDR raw timing 4423 parameters are extracted from datasheet and hard-coded into 4424 header files or board specific files. 4425 4426- CONFIG_FSL_DDR_INTERACTIVE 4427 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4428 4429- CONFIG_SYS_83XX_DDR_USES_CS0 4430 Only for 83xx systems. If specified, then DDR should 4431 be configured using CS0 and CS1 instead of CS2 and CS3. 4432 4433- CONFIG_ETHER_ON_FEC[12] 4434 Define to enable FEC[12] on a 8xx series processor. 4435 4436- CONFIG_FEC[12]_PHY 4437 Define to the hardcoded PHY address which corresponds 4438 to the given FEC; i. e. 4439 #define CONFIG_FEC1_PHY 4 4440 means that the PHY with address 4 is connected to FEC1 4441 4442 When set to -1, means to probe for first available. 4443 4444- CONFIG_FEC[12]_PHY_NORXERR 4445 The PHY does not have a RXERR line (RMII only). 4446 (so program the FEC to ignore it). 4447 4448- CONFIG_RMII 4449 Enable RMII mode for all FECs. 4450 Note that this is a global option, we can't 4451 have one FEC in standard MII mode and another in RMII mode. 4452 4453- CONFIG_CRC32_VERIFY 4454 Add a verify option to the crc32 command. 4455 The syntax is: 4456 4457 => crc32 -v <address> <count> <crc32> 4458 4459 Where address/count indicate a memory area 4460 and crc32 is the correct crc32 which the 4461 area should have. 4462 4463- CONFIG_LOOPW 4464 Add the "loopw" memory command. This only takes effect if 4465 the memory commands are activated globally (CONFIG_CMD_MEM). 4466 4467- CONFIG_MX_CYCLIC 4468 Add the "mdc" and "mwc" memory commands. These are cyclic 4469 "md/mw" commands. 4470 Examples: 4471 4472 => mdc.b 10 4 500 4473 This command will print 4 bytes (10,11,12,13) each 500 ms. 4474 4475 => mwc.l 100 12345678 10 4476 This command will write 12345678 to address 100 all 10 ms. 4477 4478 This only takes effect if the memory commands are activated 4479 globally (CONFIG_CMD_MEM). 4480 4481- CONFIG_SKIP_LOWLEVEL_INIT 4482 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4483 low level initializations (like setting up the memory 4484 controller) are omitted and/or U-Boot does not 4485 relocate itself into RAM. 4486 4487 Normally this variable MUST NOT be defined. The only 4488 exception is when U-Boot is loaded (to RAM) by some 4489 other boot loader or by a debugger which performs 4490 these initializations itself. 4491 4492- CONFIG_SPL_BUILD 4493 Modifies the behaviour of start.S when compiling a loader 4494 that is executed before the actual U-Boot. E.g. when 4495 compiling a NAND SPL. 4496 4497- CONFIG_TPL_BUILD 4498 Modifies the behaviour of start.S when compiling a loader 4499 that is executed after the SPL and before the actual U-Boot. 4500 It is loaded by the SPL. 4501 4502- CONFIG_SYS_MPC85XX_NO_RESETVEC 4503 Only for 85xx systems. If this variable is specified, the section 4504 .resetvec is not kept and the section .bootpg is placed in the 4505 previous 4k of the .text section. 4506 4507- CONFIG_ARCH_MAP_SYSMEM 4508 Generally U-Boot (and in particular the md command) uses 4509 effective address. It is therefore not necessary to regard 4510 U-Boot address as virtual addresses that need to be translated 4511 to physical addresses. However, sandbox requires this, since 4512 it maintains its own little RAM buffer which contains all 4513 addressable memory. This option causes some memory accesses 4514 to be mapped through map_sysmem() / unmap_sysmem(). 4515 4516- CONFIG_USE_ARCH_MEMCPY 4517 CONFIG_USE_ARCH_MEMSET 4518 If these options are used a optimized version of memcpy/memset will 4519 be used if available. These functions may be faster under some 4520 conditions but may increase the binary size. 4521 4522- CONFIG_X86_RESET_VECTOR 4523 If defined, the x86 reset vector code is included. This is not 4524 needed when U-Boot is running from Coreboot. 4525 4526- CONFIG_SYS_MPUCLK 4527 Defines the MPU clock speed (in MHz). 4528 4529 NOTE : currently only supported on AM335x platforms. 4530 4531- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4532 Enables the RTC32K OSC on AM33xx based plattforms 4533 4534- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4535 Option to disable subpage write in NAND driver 4536 driver that uses this: 4537 drivers/mtd/nand/davinci_nand.c 4538 4539Freescale QE/FMAN Firmware Support: 4540----------------------------------- 4541 4542The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4543loading of "firmware", which is encoded in the QE firmware binary format. 4544This firmware often needs to be loaded during U-Boot booting, so macros 4545are used to identify the storage device (NOR flash, SPI, etc) and the address 4546within that device. 4547 4548- CONFIG_SYS_FMAN_FW_ADDR 4549 The address in the storage device where the FMAN microcode is located. The 4550 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4551 is also specified. 4552 4553- CONFIG_SYS_QE_FW_ADDR 4554 The address in the storage device where the QE microcode is located. The 4555 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4556 is also specified. 4557 4558- CONFIG_SYS_QE_FMAN_FW_LENGTH 4559 The maximum possible size of the firmware. The firmware binary format 4560 has a field that specifies the actual size of the firmware, but it 4561 might not be possible to read any part of the firmware unless some 4562 local storage is allocated to hold the entire firmware first. 4563 4564- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4565 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4566 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4567 virtual address in NOR flash. 4568 4569- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4570 Specifies that QE/FMAN firmware is located in NAND flash. 4571 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4572 4573- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4574 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4575 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4576 4577- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 4578 Specifies that QE/FMAN firmware is located on the primary SPI 4579 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4580 4581- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4582 Specifies that QE/FMAN firmware is located in the remote (master) 4583 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4584 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4585 window->master inbound window->master LAW->the ucode address in 4586 master's memory space. 4587 4588Building the Software: 4589====================== 4590 4591Building U-Boot has been tested in several native build environments 4592and in many different cross environments. Of course we cannot support 4593all possibly existing versions of cross development tools in all 4594(potentially obsolete) versions. In case of tool chain problems we 4595recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4596which is extensively used to build and test U-Boot. 4597 4598If you are not using a native environment, it is assumed that you 4599have GNU cross compiling tools available in your path. In this case, 4600you must set the environment variable CROSS_COMPILE in your shell. 4601Note that no changes to the Makefile or any other source files are 4602necessary. For example using the ELDK on a 4xx CPU, please enter: 4603 4604 $ CROSS_COMPILE=ppc_4xx- 4605 $ export CROSS_COMPILE 4606 4607Note: If you wish to generate Windows versions of the utilities in 4608 the tools directory you can use the MinGW toolchain 4609 (http://www.mingw.org). Set your HOST tools to the MinGW 4610 toolchain and execute 'make tools'. For example: 4611 4612 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4613 4614 Binaries such as tools/mkimage.exe will be created which can 4615 be executed on computers running Windows. 4616 4617U-Boot is intended to be simple to build. After installing the 4618sources you must configure U-Boot for one specific board type. This 4619is done by typing: 4620 4621 make NAME_config 4622 4623where "NAME_config" is the name of one of the existing configu- 4624rations; see boards.cfg for supported names. 4625 4626Note: for some board special configuration names may exist; check if 4627 additional information is available from the board vendor; for 4628 instance, the TQM823L systems are available without (standard) 4629 or with LCD support. You can select such additional "features" 4630 when choosing the configuration, i. e. 4631 4632 make TQM823L_config 4633 - will configure for a plain TQM823L, i. e. no LCD support 4634 4635 make TQM823L_LCD_config 4636 - will configure for a TQM823L with U-Boot console on LCD 4637 4638 etc. 4639 4640 4641Finally, type "make all", and you should get some working U-Boot 4642images ready for download to / installation on your system: 4643 4644- "u-boot.bin" is a raw binary image 4645- "u-boot" is an image in ELF binary format 4646- "u-boot.srec" is in Motorola S-Record format 4647 4648By default the build is performed locally and the objects are saved 4649in the source directory. One of the two methods can be used to change 4650this behavior and build U-Boot to some external directory: 4651 46521. Add O= to the make command line invocations: 4653 4654 make O=/tmp/build distclean 4655 make O=/tmp/build NAME_config 4656 make O=/tmp/build all 4657 46582. Set environment variable BUILD_DIR to point to the desired location: 4659 4660 export BUILD_DIR=/tmp/build 4661 make distclean 4662 make NAME_config 4663 make all 4664 4665Note that the command line "O=" setting overrides the BUILD_DIR environment 4666variable. 4667 4668 4669Please be aware that the Makefiles assume you are using GNU make, so 4670for instance on NetBSD you might need to use "gmake" instead of 4671native "make". 4672 4673 4674If the system board that you have is not listed, then you will need 4675to port U-Boot to your hardware platform. To do this, follow these 4676steps: 4677 46781. Add a new configuration option for your board to the toplevel 4679 "boards.cfg" file, using the existing entries as examples. 4680 Follow the instructions there to keep the boards in order. 46812. Create a new directory to hold your board specific code. Add any 4682 files you need. In your board directory, you will need at least 4683 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 46843. Create a new configuration file "include/configs/<board>.h" for 4685 your board 46863. If you're porting U-Boot to a new CPU, then also create a new 4687 directory to hold your CPU specific code. Add any files you need. 46884. Run "make <board>_config" with your new name. 46895. Type "make", and you should get a working "u-boot.srec" file 4690 to be installed on your target system. 46916. Debug and solve any problems that might arise. 4692 [Of course, this last step is much harder than it sounds.] 4693 4694 4695Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4696============================================================== 4697 4698If you have modified U-Boot sources (for instance added a new board 4699or support for new devices, a new CPU, etc.) you are expected to 4700provide feedback to the other developers. The feedback normally takes 4701the form of a "patch", i. e. a context diff against a certain (latest 4702official or latest in the git repository) version of U-Boot sources. 4703 4704But before you submit such a patch, please verify that your modifi- 4705cation did not break existing code. At least make sure that *ALL* of 4706the supported boards compile WITHOUT ANY compiler warnings. To do so, 4707just run the "MAKEALL" script, which will configure and build U-Boot 4708for ALL supported system. Be warned, this will take a while. You can 4709select which (cross) compiler to use by passing a `CROSS_COMPILE' 4710environment variable to the script, i. e. to use the ELDK cross tools 4711you can type 4712 4713 CROSS_COMPILE=ppc_8xx- MAKEALL 4714 4715or to build on a native PowerPC system you can type 4716 4717 CROSS_COMPILE=' ' MAKEALL 4718 4719When using the MAKEALL script, the default behaviour is to build 4720U-Boot in the source directory. This location can be changed by 4721setting the BUILD_DIR environment variable. Also, for each target 4722built, the MAKEALL script saves two log files (<target>.ERR and 4723<target>.MAKEALL) in the <source dir>/LOG directory. This default 4724location can be changed by setting the MAKEALL_LOGDIR environment 4725variable. For example: 4726 4727 export BUILD_DIR=/tmp/build 4728 export MAKEALL_LOGDIR=/tmp/log 4729 CROSS_COMPILE=ppc_8xx- MAKEALL 4730 4731With the above settings build objects are saved in the /tmp/build, 4732log files are saved in the /tmp/log and the source tree remains clean 4733during the whole build process. 4734 4735 4736See also "U-Boot Porting Guide" below. 4737 4738 4739Monitor Commands - Overview: 4740============================ 4741 4742go - start application at address 'addr' 4743run - run commands in an environment variable 4744bootm - boot application image from memory 4745bootp - boot image via network using BootP/TFTP protocol 4746bootz - boot zImage from memory 4747tftpboot- boot image via network using TFTP protocol 4748 and env variables "ipaddr" and "serverip" 4749 (and eventually "gatewayip") 4750tftpput - upload a file via network using TFTP protocol 4751rarpboot- boot image via network using RARP/TFTP protocol 4752diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4753loads - load S-Record file over serial line 4754loadb - load binary file over serial line (kermit mode) 4755md - memory display 4756mm - memory modify (auto-incrementing) 4757nm - memory modify (constant address) 4758mw - memory write (fill) 4759cp - memory copy 4760cmp - memory compare 4761crc32 - checksum calculation 4762i2c - I2C sub-system 4763sspi - SPI utility commands 4764base - print or set address offset 4765printenv- print environment variables 4766setenv - set environment variables 4767saveenv - save environment variables to persistent storage 4768protect - enable or disable FLASH write protection 4769erase - erase FLASH memory 4770flinfo - print FLASH memory information 4771nand - NAND memory operations (see doc/README.nand) 4772bdinfo - print Board Info structure 4773iminfo - print header information for application image 4774coninfo - print console devices and informations 4775ide - IDE sub-system 4776loop - infinite loop on address range 4777loopw - infinite write loop on address range 4778mtest - simple RAM test 4779icache - enable or disable instruction cache 4780dcache - enable or disable data cache 4781reset - Perform RESET of the CPU 4782echo - echo args to console 4783version - print monitor version 4784help - print online help 4785? - alias for 'help' 4786 4787 4788Monitor Commands - Detailed Description: 4789======================================== 4790 4791TODO. 4792 4793For now: just type "help <command>". 4794 4795 4796Environment Variables: 4797====================== 4798 4799U-Boot supports user configuration using Environment Variables which 4800can be made persistent by saving to Flash memory. 4801 4802Environment Variables are set using "setenv", printed using 4803"printenv", and saved to Flash using "saveenv". Using "setenv" 4804without a value can be used to delete a variable from the 4805environment. As long as you don't save the environment you are 4806working with an in-memory copy. In case the Flash area containing the 4807environment is erased by accident, a default environment is provided. 4808 4809Some configuration options can be set using Environment Variables. 4810 4811List of environment variables (most likely not complete): 4812 4813 baudrate - see CONFIG_BAUDRATE 4814 4815 bootdelay - see CONFIG_BOOTDELAY 4816 4817 bootcmd - see CONFIG_BOOTCOMMAND 4818 4819 bootargs - Boot arguments when booting an RTOS image 4820 4821 bootfile - Name of the image to load with TFTP 4822 4823 bootm_low - Memory range available for image processing in the bootm 4824 command can be restricted. This variable is given as 4825 a hexadecimal number and defines lowest address allowed 4826 for use by the bootm command. See also "bootm_size" 4827 environment variable. Address defined by "bootm_low" is 4828 also the base of the initial memory mapping for the Linux 4829 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4830 bootm_mapsize. 4831 4832 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4833 This variable is given as a hexadecimal number and it 4834 defines the size of the memory region starting at base 4835 address bootm_low that is accessible by the Linux kernel 4836 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4837 as the default value if it is defined, and bootm_size is 4838 used otherwise. 4839 4840 bootm_size - Memory range available for image processing in the bootm 4841 command can be restricted. This variable is given as 4842 a hexadecimal number and defines the size of the region 4843 allowed for use by the bootm command. See also "bootm_low" 4844 environment variable. 4845 4846 updatefile - Location of the software update file on a TFTP server, used 4847 by the automatic software update feature. Please refer to 4848 documentation in doc/README.update for more details. 4849 4850 autoload - if set to "no" (any string beginning with 'n'), 4851 "bootp" will just load perform a lookup of the 4852 configuration from the BOOTP server, but not try to 4853 load any image using TFTP 4854 4855 autostart - if set to "yes", an image loaded using the "bootp", 4856 "rarpboot", "tftpboot" or "diskboot" commands will 4857 be automatically started (by internally calling 4858 "bootm") 4859 4860 If set to "no", a standalone image passed to the 4861 "bootm" command will be copied to the load address 4862 (and eventually uncompressed), but NOT be started. 4863 This can be used to load and uncompress arbitrary 4864 data. 4865 4866 fdt_high - if set this restricts the maximum address that the 4867 flattened device tree will be copied into upon boot. 4868 For example, if you have a system with 1 GB memory 4869 at physical address 0x10000000, while Linux kernel 4870 only recognizes the first 704 MB as low memory, you 4871 may need to set fdt_high as 0x3C000000 to have the 4872 device tree blob be copied to the maximum address 4873 of the 704 MB low memory, so that Linux kernel can 4874 access it during the boot procedure. 4875 4876 If this is set to the special value 0xFFFFFFFF then 4877 the fdt will not be copied at all on boot. For this 4878 to work it must reside in writable memory, have 4879 sufficient padding on the end of it for u-boot to 4880 add the information it needs into it, and the memory 4881 must be accessible by the kernel. 4882 4883 fdtcontroladdr- if set this is the address of the control flattened 4884 device tree used by U-Boot when CONFIG_OF_CONTROL is 4885 defined. 4886 4887 i2cfast - (PPC405GP|PPC405EP only) 4888 if set to 'y' configures Linux I2C driver for fast 4889 mode (400kHZ). This environment variable is used in 4890 initialization code. So, for changes to be effective 4891 it must be saved and board must be reset. 4892 4893 initrd_high - restrict positioning of initrd images: 4894 If this variable is not set, initrd images will be 4895 copied to the highest possible address in RAM; this 4896 is usually what you want since it allows for 4897 maximum initrd size. If for some reason you want to 4898 make sure that the initrd image is loaded below the 4899 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4900 variable to a value of "no" or "off" or "0". 4901 Alternatively, you can set it to a maximum upper 4902 address to use (U-Boot will still check that it 4903 does not overwrite the U-Boot stack and data). 4904 4905 For instance, when you have a system with 16 MB 4906 RAM, and want to reserve 4 MB from use by Linux, 4907 you can do this by adding "mem=12M" to the value of 4908 the "bootargs" variable. However, now you must make 4909 sure that the initrd image is placed in the first 4910 12 MB as well - this can be done with 4911 4912 setenv initrd_high 00c00000 4913 4914 If you set initrd_high to 0xFFFFFFFF, this is an 4915 indication to U-Boot that all addresses are legal 4916 for the Linux kernel, including addresses in flash 4917 memory. In this case U-Boot will NOT COPY the 4918 ramdisk at all. This may be useful to reduce the 4919 boot time on your system, but requires that this 4920 feature is supported by your Linux kernel. 4921 4922 ipaddr - IP address; needed for tftpboot command 4923 4924 loadaddr - Default load address for commands like "bootp", 4925 "rarpboot", "tftpboot", "loadb" or "diskboot" 4926 4927 loads_echo - see CONFIG_LOADS_ECHO 4928 4929 serverip - TFTP server IP address; needed for tftpboot command 4930 4931 bootretry - see CONFIG_BOOT_RETRY_TIME 4932 4933 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4934 4935 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4936 4937 ethprime - controls which interface is used first. 4938 4939 ethact - controls which interface is currently active. 4940 For example you can do the following 4941 4942 => setenv ethact FEC 4943 => ping 192.168.0.1 # traffic sent on FEC 4944 => setenv ethact SCC 4945 => ping 10.0.0.1 # traffic sent on SCC 4946 4947 ethrotate - When set to "no" U-Boot does not go through all 4948 available network interfaces. 4949 It just stays at the currently selected interface. 4950 4951 netretry - When set to "no" each network operation will 4952 either succeed or fail without retrying. 4953 When set to "once" the network operation will 4954 fail when all the available network interfaces 4955 are tried once without success. 4956 Useful on scripts which control the retry operation 4957 themselves. 4958 4959 npe_ucode - set load address for the NPE microcode 4960 4961 silent_linux - If set then linux will be told to boot silently, by 4962 changing the console to be empty. If "yes" it will be 4963 made silent. If "no" it will not be made silent. If 4964 unset, then it will be made silent if the U-Boot console 4965 is silent. 4966 4967 tftpsrcport - If this is set, the value is used for TFTP's 4968 UDP source port. 4969 4970 tftpdstport - If this is set, the value is used for TFTP's UDP 4971 destination port instead of the Well Know Port 69. 4972 4973 tftpblocksize - Block size to use for TFTP transfers; if not set, 4974 we use the TFTP server's default block size 4975 4976 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4977 seconds, minimum value is 1000 = 1 second). Defines 4978 when a packet is considered to be lost so it has to 4979 be retransmitted. The default is 5000 = 5 seconds. 4980 Lowering this value may make downloads succeed 4981 faster in networks with high packet loss rates or 4982 with unreliable TFTP servers. 4983 4984 vlan - When set to a value < 4095 the traffic over 4985 Ethernet is encapsulated/received over 802.1q 4986 VLAN tagged frames. 4987 4988The following image location variables contain the location of images 4989used in booting. The "Image" column gives the role of the image and is 4990not an environment variable name. The other columns are environment 4991variable names. "File Name" gives the name of the file on a TFTP 4992server, "RAM Address" gives the location in RAM the image will be 4993loaded to, and "Flash Location" gives the image's address in NOR 4994flash or offset in NAND flash. 4995 4996*Note* - these variables don't have to be defined for all boards, some 4997boards currenlty use other variables for these purposes, and some 4998boards use these variables for other purposes. 4999 5000Image File Name RAM Address Flash Location 5001----- --------- ----------- -------------- 5002u-boot u-boot u-boot_addr_r u-boot_addr 5003Linux kernel bootfile kernel_addr_r kernel_addr 5004device tree blob fdtfile fdt_addr_r fdt_addr 5005ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5006 5007The following environment variables may be used and automatically 5008updated by the network boot commands ("bootp" and "rarpboot"), 5009depending the information provided by your boot server: 5010 5011 bootfile - see above 5012 dnsip - IP address of your Domain Name Server 5013 dnsip2 - IP address of your secondary Domain Name Server 5014 gatewayip - IP address of the Gateway (Router) to use 5015 hostname - Target hostname 5016 ipaddr - see above 5017 netmask - Subnet Mask 5018 rootpath - Pathname of the root filesystem on the NFS server 5019 serverip - see above 5020 5021 5022There are two special Environment Variables: 5023 5024 serial# - contains hardware identification information such 5025 as type string and/or serial number 5026 ethaddr - Ethernet address 5027 5028These variables can be set only once (usually during manufacturing of 5029the board). U-Boot refuses to delete or overwrite these variables 5030once they have been set once. 5031 5032 5033Further special Environment Variables: 5034 5035 ver - Contains the U-Boot version string as printed 5036 with the "version" command. This variable is 5037 readonly (see CONFIG_VERSION_VARIABLE). 5038 5039 5040Please note that changes to some configuration parameters may take 5041only effect after the next boot (yes, that's just like Windoze :-). 5042 5043 5044Callback functions for environment variables: 5045--------------------------------------------- 5046 5047For some environment variables, the behavior of u-boot needs to change 5048when their values are changed. This functionailty allows functions to 5049be associated with arbitrary variables. On creation, overwrite, or 5050deletion, the callback will provide the opportunity for some side 5051effect to happen or for the change to be rejected. 5052 5053The callbacks are named and associated with a function using the 5054U_BOOT_ENV_CALLBACK macro in your board or driver code. 5055 5056These callbacks are associated with variables in one of two ways. The 5057static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5058in the board configuration to a string that defines a list of 5059associations. The list must be in the following format: 5060 5061 entry = variable_name[:callback_name] 5062 list = entry[,list] 5063 5064If the callback name is not specified, then the callback is deleted. 5065Spaces are also allowed anywhere in the list. 5066 5067Callbacks can also be associated by defining the ".callbacks" variable 5068with the same list format above. Any association in ".callbacks" will 5069override any association in the static list. You can define 5070CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5071".callbacks" envirnoment variable in the default or embedded environment. 5072 5073 5074Command Line Parsing: 5075===================== 5076 5077There are two different command line parsers available with U-Boot: 5078the old "simple" one, and the much more powerful "hush" shell: 5079 5080Old, simple command line parser: 5081-------------------------------- 5082 5083- supports environment variables (through setenv / saveenv commands) 5084- several commands on one line, separated by ';' 5085- variable substitution using "... ${name} ..." syntax 5086- special characters ('$', ';') can be escaped by prefixing with '\', 5087 for example: 5088 setenv bootcmd bootm \${address} 5089- You can also escape text by enclosing in single apostrophes, for example: 5090 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5091 5092Hush shell: 5093----------- 5094 5095- similar to Bourne shell, with control structures like 5096 if...then...else...fi, for...do...done; while...do...done, 5097 until...do...done, ... 5098- supports environment ("global") variables (through setenv / saveenv 5099 commands) and local shell variables (through standard shell syntax 5100 "name=value"); only environment variables can be used with "run" 5101 command 5102 5103General rules: 5104-------------- 5105 5106(1) If a command line (or an environment variable executed by a "run" 5107 command) contains several commands separated by semicolon, and 5108 one of these commands fails, then the remaining commands will be 5109 executed anyway. 5110 5111(2) If you execute several variables with one call to run (i. e. 5112 calling run with a list of variables as arguments), any failing 5113 command will cause "run" to terminate, i. e. the remaining 5114 variables are not executed. 5115 5116Note for Redundant Ethernet Interfaces: 5117======================================= 5118 5119Some boards come with redundant Ethernet interfaces; U-Boot supports 5120such configurations and is capable of automatic selection of a 5121"working" interface when needed. MAC assignment works as follows: 5122 5123Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5124MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5125"eth1addr" (=>eth1), "eth2addr", ... 5126 5127If the network interface stores some valid MAC address (for instance 5128in SROM), this is used as default address if there is NO correspon- 5129ding setting in the environment; if the corresponding environment 5130variable is set, this overrides the settings in the card; that means: 5131 5132o If the SROM has a valid MAC address, and there is no address in the 5133 environment, the SROM's address is used. 5134 5135o If there is no valid address in the SROM, and a definition in the 5136 environment exists, then the value from the environment variable is 5137 used. 5138 5139o If both the SROM and the environment contain a MAC address, and 5140 both addresses are the same, this MAC address is used. 5141 5142o If both the SROM and the environment contain a MAC address, and the 5143 addresses differ, the value from the environment is used and a 5144 warning is printed. 5145 5146o If neither SROM nor the environment contain a MAC address, an error 5147 is raised. 5148 5149If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5150will be programmed into hardware as part of the initialization process. This 5151may be skipped by setting the appropriate 'ethmacskip' environment variable. 5152The naming convention is as follows: 5153"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5154 5155Image Formats: 5156============== 5157 5158U-Boot is capable of booting (and performing other auxiliary operations on) 5159images in two formats: 5160 5161New uImage format (FIT) 5162----------------------- 5163 5164Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5165to Flattened Device Tree). It allows the use of images with multiple 5166components (several kernels, ramdisks, etc.), with contents protected by 5167SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5168 5169 5170Old uImage format 5171----------------- 5172 5173Old image format is based on binary files which can be basically anything, 5174preceded by a special header; see the definitions in include/image.h for 5175details; basically, the header defines the following image properties: 5176 5177* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5178 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5179 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5180 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5181 INTEGRITY). 5182* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5183 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5184 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5185* Compression Type (uncompressed, gzip, bzip2) 5186* Load Address 5187* Entry Point 5188* Image Name 5189* Image Timestamp 5190 5191The header is marked by a special Magic Number, and both the header 5192and the data portions of the image are secured against corruption by 5193CRC32 checksums. 5194 5195 5196Linux Support: 5197============== 5198 5199Although U-Boot should support any OS or standalone application 5200easily, the main focus has always been on Linux during the design of 5201U-Boot. 5202 5203U-Boot includes many features that so far have been part of some 5204special "boot loader" code within the Linux kernel. Also, any 5205"initrd" images to be used are no longer part of one big Linux image; 5206instead, kernel and "initrd" are separate images. This implementation 5207serves several purposes: 5208 5209- the same features can be used for other OS or standalone 5210 applications (for instance: using compressed images to reduce the 5211 Flash memory footprint) 5212 5213- it becomes much easier to port new Linux kernel versions because 5214 lots of low-level, hardware dependent stuff are done by U-Boot 5215 5216- the same Linux kernel image can now be used with different "initrd" 5217 images; of course this also means that different kernel images can 5218 be run with the same "initrd". This makes testing easier (you don't 5219 have to build a new "zImage.initrd" Linux image when you just 5220 change a file in your "initrd"). Also, a field-upgrade of the 5221 software is easier now. 5222 5223 5224Linux HOWTO: 5225============ 5226 5227Porting Linux to U-Boot based systems: 5228--------------------------------------- 5229 5230U-Boot cannot save you from doing all the necessary modifications to 5231configure the Linux device drivers for use with your target hardware 5232(no, we don't intend to provide a full virtual machine interface to 5233Linux :-). 5234 5235But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5236 5237Just make sure your machine specific header file (for instance 5238include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5239Information structure as we define in include/asm-<arch>/u-boot.h, 5240and make sure that your definition of IMAP_ADDR uses the same value 5241as your U-Boot configuration in CONFIG_SYS_IMMR. 5242 5243 5244Configuring the Linux kernel: 5245----------------------------- 5246 5247No specific requirements for U-Boot. Make sure you have some root 5248device (initial ramdisk, NFS) for your target system. 5249 5250 5251Building a Linux Image: 5252----------------------- 5253 5254With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5255not used. If you use recent kernel source, a new build target 5256"uImage" will exist which automatically builds an image usable by 5257U-Boot. Most older kernels also have support for a "pImage" target, 5258which was introduced for our predecessor project PPCBoot and uses a 5259100% compatible format. 5260 5261Example: 5262 5263 make TQM850L_config 5264 make oldconfig 5265 make dep 5266 make uImage 5267 5268The "uImage" build target uses a special tool (in 'tools/mkimage') to 5269encapsulate a compressed Linux kernel image with header information, 5270CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5271 5272* build a standard "vmlinux" kernel image (in ELF binary format): 5273 5274* convert the kernel into a raw binary image: 5275 5276 ${CROSS_COMPILE}-objcopy -O binary \ 5277 -R .note -R .comment \ 5278 -S vmlinux linux.bin 5279 5280* compress the binary image: 5281 5282 gzip -9 linux.bin 5283 5284* package compressed binary image for U-Boot: 5285 5286 mkimage -A ppc -O linux -T kernel -C gzip \ 5287 -a 0 -e 0 -n "Linux Kernel Image" \ 5288 -d linux.bin.gz uImage 5289 5290 5291The "mkimage" tool can also be used to create ramdisk images for use 5292with U-Boot, either separated from the Linux kernel image, or 5293combined into one file. "mkimage" encapsulates the images with a 64 5294byte header containing information about target architecture, 5295operating system, image type, compression method, entry points, time 5296stamp, CRC32 checksums, etc. 5297 5298"mkimage" can be called in two ways: to verify existing images and 5299print the header information, or to build new images. 5300 5301In the first form (with "-l" option) mkimage lists the information 5302contained in the header of an existing U-Boot image; this includes 5303checksum verification: 5304 5305 tools/mkimage -l image 5306 -l ==> list image header information 5307 5308The second form (with "-d" option) is used to build a U-Boot image 5309from a "data file" which is used as image payload: 5310 5311 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5312 -n name -d data_file image 5313 -A ==> set architecture to 'arch' 5314 -O ==> set operating system to 'os' 5315 -T ==> set image type to 'type' 5316 -C ==> set compression type 'comp' 5317 -a ==> set load address to 'addr' (hex) 5318 -e ==> set entry point to 'ep' (hex) 5319 -n ==> set image name to 'name' 5320 -d ==> use image data from 'datafile' 5321 5322Right now, all Linux kernels for PowerPC systems use the same load 5323address (0x00000000), but the entry point address depends on the 5324kernel version: 5325 5326- 2.2.x kernels have the entry point at 0x0000000C, 5327- 2.3.x and later kernels have the entry point at 0x00000000. 5328 5329So a typical call to build a U-Boot image would read: 5330 5331 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5332 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5333 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5334 > examples/uImage.TQM850L 5335 Image Name: 2.4.4 kernel for TQM850L 5336 Created: Wed Jul 19 02:34:59 2000 5337 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5338 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5339 Load Address: 0x00000000 5340 Entry Point: 0x00000000 5341 5342To verify the contents of the image (or check for corruption): 5343 5344 -> tools/mkimage -l examples/uImage.TQM850L 5345 Image Name: 2.4.4 kernel for TQM850L 5346 Created: Wed Jul 19 02:34:59 2000 5347 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5348 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5349 Load Address: 0x00000000 5350 Entry Point: 0x00000000 5351 5352NOTE: for embedded systems where boot time is critical you can trade 5353speed for memory and install an UNCOMPRESSED image instead: this 5354needs more space in Flash, but boots much faster since it does not 5355need to be uncompressed: 5356 5357 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5358 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5359 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5360 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5361 > examples/uImage.TQM850L-uncompressed 5362 Image Name: 2.4.4 kernel for TQM850L 5363 Created: Wed Jul 19 02:34:59 2000 5364 Image Type: PowerPC Linux Kernel Image (uncompressed) 5365 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5366 Load Address: 0x00000000 5367 Entry Point: 0x00000000 5368 5369 5370Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5371when your kernel is intended to use an initial ramdisk: 5372 5373 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5374 > -A ppc -O linux -T ramdisk -C gzip \ 5375 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5376 Image Name: Simple Ramdisk Image 5377 Created: Wed Jan 12 14:01:50 2000 5378 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5379 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5380 Load Address: 0x00000000 5381 Entry Point: 0x00000000 5382 5383The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5384option performs the converse operation of the mkimage's second form (the "-d" 5385option). Given an image built by mkimage, the dumpimage extracts a "data file" 5386from the image: 5387 5388 tools/dumpimage -i image -p position data_file 5389 -i ==> extract from the 'image' a specific 'data_file', \ 5390 indexed by 'position' 5391 5392 5393Installing a Linux Image: 5394------------------------- 5395 5396To downloading a U-Boot image over the serial (console) interface, 5397you must convert the image to S-Record format: 5398 5399 objcopy -I binary -O srec examples/image examples/image.srec 5400 5401The 'objcopy' does not understand the information in the U-Boot 5402image header, so the resulting S-Record file will be relative to 5403address 0x00000000. To load it to a given address, you need to 5404specify the target address as 'offset' parameter with the 'loads' 5405command. 5406 5407Example: install the image to address 0x40100000 (which on the 5408TQM8xxL is in the first Flash bank): 5409 5410 => erase 40100000 401FFFFF 5411 5412 .......... done 5413 Erased 8 sectors 5414 5415 => loads 40100000 5416 ## Ready for S-Record download ... 5417 ~>examples/image.srec 5418 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5419 ... 5420 15989 15990 15991 15992 5421 [file transfer complete] 5422 [connected] 5423 ## Start Addr = 0x00000000 5424 5425 5426You can check the success of the download using the 'iminfo' command; 5427this includes a checksum verification so you can be sure no data 5428corruption happened: 5429 5430 => imi 40100000 5431 5432 ## Checking Image at 40100000 ... 5433 Image Name: 2.2.13 for initrd on TQM850L 5434 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5435 Data Size: 335725 Bytes = 327 kB = 0 MB 5436 Load Address: 00000000 5437 Entry Point: 0000000c 5438 Verifying Checksum ... OK 5439 5440 5441Boot Linux: 5442----------- 5443 5444The "bootm" command is used to boot an application that is stored in 5445memory (RAM or Flash). In case of a Linux kernel image, the contents 5446of the "bootargs" environment variable is passed to the kernel as 5447parameters. You can check and modify this variable using the 5448"printenv" and "setenv" commands: 5449 5450 5451 => printenv bootargs 5452 bootargs=root=/dev/ram 5453 5454 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5455 5456 => printenv bootargs 5457 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5458 5459 => bootm 40020000 5460 ## Booting Linux kernel at 40020000 ... 5461 Image Name: 2.2.13 for NFS on TQM850L 5462 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5463 Data Size: 381681 Bytes = 372 kB = 0 MB 5464 Load Address: 00000000 5465 Entry Point: 0000000c 5466 Verifying Checksum ... OK 5467 Uncompressing Kernel Image ... OK 5468 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 5469 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5470 time_init: decrementer frequency = 187500000/60 5471 Calibrating delay loop... 49.77 BogoMIPS 5472 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5473 ... 5474 5475If you want to boot a Linux kernel with initial RAM disk, you pass 5476the memory addresses of both the kernel and the initrd image (PPBCOOT 5477format!) to the "bootm" command: 5478 5479 => imi 40100000 40200000 5480 5481 ## Checking Image at 40100000 ... 5482 Image Name: 2.2.13 for initrd on TQM850L 5483 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5484 Data Size: 335725 Bytes = 327 kB = 0 MB 5485 Load Address: 00000000 5486 Entry Point: 0000000c 5487 Verifying Checksum ... OK 5488 5489 ## Checking Image at 40200000 ... 5490 Image Name: Simple Ramdisk Image 5491 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5492 Data Size: 566530 Bytes = 553 kB = 0 MB 5493 Load Address: 00000000 5494 Entry Point: 00000000 5495 Verifying Checksum ... OK 5496 5497 => bootm 40100000 40200000 5498 ## Booting Linux kernel at 40100000 ... 5499 Image Name: 2.2.13 for initrd on TQM850L 5500 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5501 Data Size: 335725 Bytes = 327 kB = 0 MB 5502 Load Address: 00000000 5503 Entry Point: 0000000c 5504 Verifying Checksum ... OK 5505 Uncompressing Kernel Image ... OK 5506 ## Loading RAMDisk Image at 40200000 ... 5507 Image Name: Simple Ramdisk Image 5508 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5509 Data Size: 566530 Bytes = 553 kB = 0 MB 5510 Load Address: 00000000 5511 Entry Point: 00000000 5512 Verifying Checksum ... OK 5513 Loading Ramdisk ... OK 5514 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 5515 Boot arguments: root=/dev/ram 5516 time_init: decrementer frequency = 187500000/60 5517 Calibrating delay loop... 49.77 BogoMIPS 5518 ... 5519 RAMDISK: Compressed image found at block 0 5520 VFS: Mounted root (ext2 filesystem). 5521 5522 bash# 5523 5524Boot Linux and pass a flat device tree: 5525----------- 5526 5527First, U-Boot must be compiled with the appropriate defines. See the section 5528titled "Linux Kernel Interface" above for a more in depth explanation. The 5529following is an example of how to start a kernel and pass an updated 5530flat device tree: 5531 5532=> print oftaddr 5533oftaddr=0x300000 5534=> print oft 5535oft=oftrees/mpc8540ads.dtb 5536=> tftp $oftaddr $oft 5537Speed: 1000, full duplex 5538Using TSEC0 device 5539TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5540Filename 'oftrees/mpc8540ads.dtb'. 5541Load address: 0x300000 5542Loading: # 5543done 5544Bytes transferred = 4106 (100a hex) 5545=> tftp $loadaddr $bootfile 5546Speed: 1000, full duplex 5547Using TSEC0 device 5548TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5549Filename 'uImage'. 5550Load address: 0x200000 5551Loading:############ 5552done 5553Bytes transferred = 1029407 (fb51f hex) 5554=> print loadaddr 5555loadaddr=200000 5556=> print oftaddr 5557oftaddr=0x300000 5558=> bootm $loadaddr - $oftaddr 5559## Booting image at 00200000 ... 5560 Image Name: Linux-2.6.17-dirty 5561 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5562 Data Size: 1029343 Bytes = 1005.2 kB 5563 Load Address: 00000000 5564 Entry Point: 00000000 5565 Verifying Checksum ... OK 5566 Uncompressing Kernel Image ... OK 5567Booting using flat device tree at 0x300000 5568Using MPC85xx ADS machine description 5569Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5570[snip] 5571 5572 5573More About U-Boot Image Types: 5574------------------------------ 5575 5576U-Boot supports the following image types: 5577 5578 "Standalone Programs" are directly runnable in the environment 5579 provided by U-Boot; it is expected that (if they behave 5580 well) you can continue to work in U-Boot after return from 5581 the Standalone Program. 5582 "OS Kernel Images" are usually images of some Embedded OS which 5583 will take over control completely. Usually these programs 5584 will install their own set of exception handlers, device 5585 drivers, set up the MMU, etc. - this means, that you cannot 5586 expect to re-enter U-Boot except by resetting the CPU. 5587 "RAMDisk Images" are more or less just data blocks, and their 5588 parameters (address, size) are passed to an OS kernel that is 5589 being started. 5590 "Multi-File Images" contain several images, typically an OS 5591 (Linux) kernel image and one or more data images like 5592 RAMDisks. This construct is useful for instance when you want 5593 to boot over the network using BOOTP etc., where the boot 5594 server provides just a single image file, but you want to get 5595 for instance an OS kernel and a RAMDisk image. 5596 5597 "Multi-File Images" start with a list of image sizes, each 5598 image size (in bytes) specified by an "uint32_t" in network 5599 byte order. This list is terminated by an "(uint32_t)0". 5600 Immediately after the terminating 0 follow the images, one by 5601 one, all aligned on "uint32_t" boundaries (size rounded up to 5602 a multiple of 4 bytes). 5603 5604 "Firmware Images" are binary images containing firmware (like 5605 U-Boot or FPGA images) which usually will be programmed to 5606 flash memory. 5607 5608 "Script files" are command sequences that will be executed by 5609 U-Boot's command interpreter; this feature is especially 5610 useful when you configure U-Boot to use a real shell (hush) 5611 as command interpreter. 5612 5613Booting the Linux zImage: 5614------------------------- 5615 5616On some platforms, it's possible to boot Linux zImage. This is done 5617using the "bootz" command. The syntax of "bootz" command is the same 5618as the syntax of "bootm" command. 5619 5620Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5621kernel with raw initrd images. The syntax is slightly different, the 5622address of the initrd must be augmented by it's size, in the following 5623format: "<initrd addres>:<initrd size>". 5624 5625 5626Standalone HOWTO: 5627================= 5628 5629One of the features of U-Boot is that you can dynamically load and 5630run "standalone" applications, which can use some resources of 5631U-Boot like console I/O functions or interrupt services. 5632 5633Two simple examples are included with the sources: 5634 5635"Hello World" Demo: 5636------------------- 5637 5638'examples/hello_world.c' contains a small "Hello World" Demo 5639application; it is automatically compiled when you build U-Boot. 5640It's configured to run at address 0x00040004, so you can play with it 5641like that: 5642 5643 => loads 5644 ## Ready for S-Record download ... 5645 ~>examples/hello_world.srec 5646 1 2 3 4 5 6 7 8 9 10 11 ... 5647 [file transfer complete] 5648 [connected] 5649 ## Start Addr = 0x00040004 5650 5651 => go 40004 Hello World! This is a test. 5652 ## Starting application at 0x00040004 ... 5653 Hello World 5654 argc = 7 5655 argv[0] = "40004" 5656 argv[1] = "Hello" 5657 argv[2] = "World!" 5658 argv[3] = "This" 5659 argv[4] = "is" 5660 argv[5] = "a" 5661 argv[6] = "test." 5662 argv[7] = "<NULL>" 5663 Hit any key to exit ... 5664 5665 ## Application terminated, rc = 0x0 5666 5667Another example, which demonstrates how to register a CPM interrupt 5668handler with the U-Boot code, can be found in 'examples/timer.c'. 5669Here, a CPM timer is set up to generate an interrupt every second. 5670The interrupt service routine is trivial, just printing a '.' 5671character, but this is just a demo program. The application can be 5672controlled by the following keys: 5673 5674 ? - print current values og the CPM Timer registers 5675 b - enable interrupts and start timer 5676 e - stop timer and disable interrupts 5677 q - quit application 5678 5679 => loads 5680 ## Ready for S-Record download ... 5681 ~>examples/timer.srec 5682 1 2 3 4 5 6 7 8 9 10 11 ... 5683 [file transfer complete] 5684 [connected] 5685 ## Start Addr = 0x00040004 5686 5687 => go 40004 5688 ## Starting application at 0x00040004 ... 5689 TIMERS=0xfff00980 5690 Using timer 1 5691 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5692 5693Hit 'b': 5694 [q, b, e, ?] Set interval 1000000 us 5695 Enabling timer 5696Hit '?': 5697 [q, b, e, ?] ........ 5698 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5699Hit '?': 5700 [q, b, e, ?] . 5701 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5702Hit '?': 5703 [q, b, e, ?] . 5704 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5705Hit '?': 5706 [q, b, e, ?] . 5707 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5708Hit 'e': 5709 [q, b, e, ?] ...Stopping timer 5710Hit 'q': 5711 [q, b, e, ?] ## Application terminated, rc = 0x0 5712 5713 5714Minicom warning: 5715================ 5716 5717Over time, many people have reported problems when trying to use the 5718"minicom" terminal emulation program for serial download. I (wd) 5719consider minicom to be broken, and recommend not to use it. Under 5720Unix, I recommend to use C-Kermit for general purpose use (and 5721especially for kermit binary protocol download ("loadb" command), and 5722use "cu" for S-Record download ("loads" command). See 5723http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5724for help with kermit. 5725 5726 5727Nevertheless, if you absolutely want to use it try adding this 5728configuration to your "File transfer protocols" section: 5729 5730 Name Program Name U/D FullScr IO-Red. Multi 5731 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5732 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5733 5734 5735NetBSD Notes: 5736============= 5737 5738Starting at version 0.9.2, U-Boot supports NetBSD both as host 5739(build U-Boot) and target system (boots NetBSD/mpc8xx). 5740 5741Building requires a cross environment; it is known to work on 5742NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5743need gmake since the Makefiles are not compatible with BSD make). 5744Note that the cross-powerpc package does not install include files; 5745attempting to build U-Boot will fail because <machine/ansi.h> is 5746missing. This file has to be installed and patched manually: 5747 5748 # cd /usr/pkg/cross/powerpc-netbsd/include 5749 # mkdir powerpc 5750 # ln -s powerpc machine 5751 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5752 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5753 5754Native builds *don't* work due to incompatibilities between native 5755and U-Boot include files. 5756 5757Booting assumes that (the first part of) the image booted is a 5758stage-2 loader which in turn loads and then invokes the kernel 5759proper. Loader sources will eventually appear in the NetBSD source 5760tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5761meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5762 5763 5764Implementation Internals: 5765========================= 5766 5767The following is not intended to be a complete description of every 5768implementation detail. However, it should help to understand the 5769inner workings of U-Boot and make it easier to port it to custom 5770hardware. 5771 5772 5773Initial Stack, Global Data: 5774--------------------------- 5775 5776The implementation of U-Boot is complicated by the fact that U-Boot 5777starts running out of ROM (flash memory), usually without access to 5778system RAM (because the memory controller is not initialized yet). 5779This means that we don't have writable Data or BSS segments, and BSS 5780is not initialized as zero. To be able to get a C environment working 5781at all, we have to allocate at least a minimal stack. Implementation 5782options for this are defined and restricted by the CPU used: Some CPU 5783models provide on-chip memory (like the IMMR area on MPC8xx and 5784MPC826x processors), on others (parts of) the data cache can be 5785locked as (mis-) used as memory, etc. 5786 5787 Chris Hallinan posted a good summary of these issues to the 5788 U-Boot mailing list: 5789 5790 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5791 From: "Chris Hallinan" <clh@net1plus.com> 5792 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5793 ... 5794 5795 Correct me if I'm wrong, folks, but the way I understand it 5796 is this: Using DCACHE as initial RAM for Stack, etc, does not 5797 require any physical RAM backing up the cache. The cleverness 5798 is that the cache is being used as a temporary supply of 5799 necessary storage before the SDRAM controller is setup. It's 5800 beyond the scope of this list to explain the details, but you 5801 can see how this works by studying the cache architecture and 5802 operation in the architecture and processor-specific manuals. 5803 5804 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5805 is another option for the system designer to use as an 5806 initial stack/RAM area prior to SDRAM being available. Either 5807 option should work for you. Using CS 4 should be fine if your 5808 board designers haven't used it for something that would 5809 cause you grief during the initial boot! It is frequently not 5810 used. 5811 5812 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5813 with your processor/board/system design. The default value 5814 you will find in any recent u-boot distribution in 5815 walnut.h should work for you. I'd set it to a value larger 5816 than your SDRAM module. If you have a 64MB SDRAM module, set 5817 it above 400_0000. Just make sure your board has no resources 5818 that are supposed to respond to that address! That code in 5819 start.S has been around a while and should work as is when 5820 you get the config right. 5821 5822 -Chris Hallinan 5823 DS4.COM, Inc. 5824 5825It is essential to remember this, since it has some impact on the C 5826code for the initialization procedures: 5827 5828* Initialized global data (data segment) is read-only. Do not attempt 5829 to write it. 5830 5831* Do not use any uninitialized global data (or implicitely initialized 5832 as zero data - BSS segment) at all - this is undefined, initiali- 5833 zation is performed later (when relocating to RAM). 5834 5835* Stack space is very limited. Avoid big data buffers or things like 5836 that. 5837 5838Having only the stack as writable memory limits means we cannot use 5839normal global data to share information beween the code. But it 5840turned out that the implementation of U-Boot can be greatly 5841simplified by making a global data structure (gd_t) available to all 5842functions. We could pass a pointer to this data as argument to _all_ 5843functions, but this would bloat the code. Instead we use a feature of 5844the GCC compiler (Global Register Variables) to share the data: we 5845place a pointer (gd) to the global data into a register which we 5846reserve for this purpose. 5847 5848When choosing a register for such a purpose we are restricted by the 5849relevant (E)ABI specifications for the current architecture, and by 5850GCC's implementation. 5851 5852For PowerPC, the following registers have specific use: 5853 R1: stack pointer 5854 R2: reserved for system use 5855 R3-R4: parameter passing and return values 5856 R5-R10: parameter passing 5857 R13: small data area pointer 5858 R30: GOT pointer 5859 R31: frame pointer 5860 5861 (U-Boot also uses R12 as internal GOT pointer. r12 5862 is a volatile register so r12 needs to be reset when 5863 going back and forth between asm and C) 5864 5865 ==> U-Boot will use R2 to hold a pointer to the global data 5866 5867 Note: on PPC, we could use a static initializer (since the 5868 address of the global data structure is known at compile time), 5869 but it turned out that reserving a register results in somewhat 5870 smaller code - although the code savings are not that big (on 5871 average for all boards 752 bytes for the whole U-Boot image, 5872 624 text + 127 data). 5873 5874On Blackfin, the normal C ABI (except for P3) is followed as documented here: 5875 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 5876 5877 ==> U-Boot will use P3 to hold a pointer to the global data 5878 5879On ARM, the following registers are used: 5880 5881 R0: function argument word/integer result 5882 R1-R3: function argument word 5883 R9: platform specific 5884 R10: stack limit (used only if stack checking is enabled) 5885 R11: argument (frame) pointer 5886 R12: temporary workspace 5887 R13: stack pointer 5888 R14: link register 5889 R15: program counter 5890 5891 ==> U-Boot will use R9 to hold a pointer to the global data 5892 5893 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5894 5895On Nios II, the ABI is documented here: 5896 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5897 5898 ==> U-Boot will use gp to hold a pointer to the global data 5899 5900 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5901 to access small data sections, so gp is free. 5902 5903On NDS32, the following registers are used: 5904 5905 R0-R1: argument/return 5906 R2-R5: argument 5907 R15: temporary register for assembler 5908 R16: trampoline register 5909 R28: frame pointer (FP) 5910 R29: global pointer (GP) 5911 R30: link register (LP) 5912 R31: stack pointer (SP) 5913 PC: program counter (PC) 5914 5915 ==> U-Boot will use R10 to hold a pointer to the global data 5916 5917NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5918or current versions of GCC may "optimize" the code too much. 5919 5920Memory Management: 5921------------------ 5922 5923U-Boot runs in system state and uses physical addresses, i.e. the 5924MMU is not used either for address mapping nor for memory protection. 5925 5926The available memory is mapped to fixed addresses using the memory 5927controller. In this process, a contiguous block is formed for each 5928memory type (Flash, SDRAM, SRAM), even when it consists of several 5929physical memory banks. 5930 5931U-Boot is installed in the first 128 kB of the first Flash bank (on 5932TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5933booting and sizing and initializing DRAM, the code relocates itself 5934to the upper end of DRAM. Immediately below the U-Boot code some 5935memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5936configuration setting]. Below that, a structure with global Board 5937Info data is placed, followed by the stack (growing downward). 5938 5939Additionally, some exception handler code is copied to the low 8 kB 5940of DRAM (0x00000000 ... 0x00001FFF). 5941 5942So a typical memory configuration with 16 MB of DRAM could look like 5943this: 5944 5945 0x0000 0000 Exception Vector code 5946 : 5947 0x0000 1FFF 5948 0x0000 2000 Free for Application Use 5949 : 5950 : 5951 5952 : 5953 : 5954 0x00FB FF20 Monitor Stack (Growing downward) 5955 0x00FB FFAC Board Info Data and permanent copy of global data 5956 0x00FC 0000 Malloc Arena 5957 : 5958 0x00FD FFFF 5959 0x00FE 0000 RAM Copy of Monitor Code 5960 ... eventually: LCD or video framebuffer 5961 ... eventually: pRAM (Protected RAM - unchanged by reset) 5962 0x00FF FFFF [End of RAM] 5963 5964 5965System Initialization: 5966---------------------- 5967 5968In the reset configuration, U-Boot starts at the reset entry point 5969(on most PowerPC systems at address 0x00000100). Because of the reset 5970configuration for CS0# this is a mirror of the onboard Flash memory. 5971To be able to re-map memory U-Boot then jumps to its link address. 5972To be able to implement the initialization code in C, a (small!) 5973initial stack is set up in the internal Dual Ported RAM (in case CPUs 5974which provide such a feature like MPC8xx or MPC8260), or in a locked 5975part of the data cache. After that, U-Boot initializes the CPU core, 5976the caches and the SIU. 5977 5978Next, all (potentially) available memory banks are mapped using a 5979preliminary mapping. For example, we put them on 512 MB boundaries 5980(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5981on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5982programmed for SDRAM access. Using the temporary configuration, a 5983simple memory test is run that determines the size of the SDRAM 5984banks. 5985 5986When there is more than one SDRAM bank, and the banks are of 5987different size, the largest is mapped first. For equal size, the first 5988bank (CS2#) is mapped first. The first mapping is always for address 59890x00000000, with any additional banks following immediately to create 5990contiguous memory starting from 0. 5991 5992Then, the monitor installs itself at the upper end of the SDRAM area 5993and allocates memory for use by malloc() and for the global Board 5994Info data; also, the exception vector code is copied to the low RAM 5995pages, and the final stack is set up. 5996 5997Only after this relocation will you have a "normal" C environment; 5998until that you are restricted in several ways, mostly because you are 5999running from ROM, and because the code will have to be relocated to a 6000new address in RAM. 6001 6002 6003U-Boot Porting Guide: 6004---------------------- 6005 6006[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6007list, October 2002] 6008 6009 6010int main(int argc, char *argv[]) 6011{ 6012 sighandler_t no_more_time; 6013 6014 signal(SIGALRM, no_more_time); 6015 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6016 6017 if (available_money > available_manpower) { 6018 Pay consultant to port U-Boot; 6019 return 0; 6020 } 6021 6022 Download latest U-Boot source; 6023 6024 Subscribe to u-boot mailing list; 6025 6026 if (clueless) 6027 email("Hi, I am new to U-Boot, how do I get started?"); 6028 6029 while (learning) { 6030 Read the README file in the top level directory; 6031 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6032 Read applicable doc/*.README; 6033 Read the source, Luke; 6034 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6035 } 6036 6037 if (available_money > toLocalCurrency ($2500)) 6038 Buy a BDI3000; 6039 else 6040 Add a lot of aggravation and time; 6041 6042 if (a similar board exists) { /* hopefully... */ 6043 cp -a board/<similar> board/<myboard> 6044 cp include/configs/<similar>.h include/configs/<myboard>.h 6045 } else { 6046 Create your own board support subdirectory; 6047 Create your own board include/configs/<myboard>.h file; 6048 } 6049 Edit new board/<myboard> files 6050 Edit new include/configs/<myboard>.h 6051 6052 while (!accepted) { 6053 while (!running) { 6054 do { 6055 Add / modify source code; 6056 } until (compiles); 6057 Debug; 6058 if (clueless) 6059 email("Hi, I am having problems..."); 6060 } 6061 Send patch file to the U-Boot email list; 6062 if (reasonable critiques) 6063 Incorporate improvements from email list code review; 6064 else 6065 Defend code as written; 6066 } 6067 6068 return 0; 6069} 6070 6071void no_more_time (int sig) 6072{ 6073 hire_a_guru(); 6074} 6075 6076 6077Coding Standards: 6078----------------- 6079 6080All contributions to U-Boot should conform to the Linux kernel 6081coding style; see the file "Documentation/CodingStyle" and the script 6082"scripts/Lindent" in your Linux kernel source directory. 6083 6084Source files originating from a different project (for example the 6085MTD subsystem) are generally exempt from these guidelines and are not 6086reformated to ease subsequent migration to newer versions of those 6087sources. 6088 6089Please note that U-Boot is implemented in C (and to some small parts in 6090Assembler); no C++ is used, so please do not use C++ style comments (//) 6091in your code. 6092 6093Please also stick to the following formatting rules: 6094- remove any trailing white space 6095- use TAB characters for indentation and vertical alignment, not spaces 6096- make sure NOT to use DOS '\r\n' line feeds 6097- do not add more than 2 consecutive empty lines to source files 6098- do not add trailing empty lines to source files 6099 6100Submissions which do not conform to the standards may be returned 6101with a request to reformat the changes. 6102 6103 6104Submitting Patches: 6105------------------- 6106 6107Since the number of patches for U-Boot is growing, we need to 6108establish some rules. Submissions which do not conform to these rules 6109may be rejected, even when they contain important and valuable stuff. 6110 6111Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6112 6113Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6114see http://lists.denx.de/mailman/listinfo/u-boot 6115 6116When you send a patch, please include the following information with 6117it: 6118 6119* For bug fixes: a description of the bug and how your patch fixes 6120 this bug. Please try to include a way of demonstrating that the 6121 patch actually fixes something. 6122 6123* For new features: a description of the feature and your 6124 implementation. 6125 6126* A CHANGELOG entry as plaintext (separate from the patch) 6127 6128* For major contributions, your entry to the CREDITS file 6129 6130* When you add support for a new board, don't forget to add a 6131 maintainer e-mail address to the boards.cfg file, too. 6132 6133* If your patch adds new configuration options, don't forget to 6134 document these in the README file. 6135 6136* The patch itself. If you are using git (which is *strongly* 6137 recommended) you can easily generate the patch using the 6138 "git format-patch". If you then use "git send-email" to send it to 6139 the U-Boot mailing list, you will avoid most of the common problems 6140 with some other mail clients. 6141 6142 If you cannot use git, use "diff -purN OLD NEW". If your version of 6143 diff does not support these options, then get the latest version of 6144 GNU diff. 6145 6146 The current directory when running this command shall be the parent 6147 directory of the U-Boot source tree (i. e. please make sure that 6148 your patch includes sufficient directory information for the 6149 affected files). 6150 6151 We prefer patches as plain text. MIME attachments are discouraged, 6152 and compressed attachments must not be used. 6153 6154* If one logical set of modifications affects or creates several 6155 files, all these changes shall be submitted in a SINGLE patch file. 6156 6157* Changesets that contain different, unrelated modifications shall be 6158 submitted as SEPARATE patches, one patch per changeset. 6159 6160 6161Notes: 6162 6163* Before sending the patch, run the MAKEALL script on your patched 6164 source tree and make sure that no errors or warnings are reported 6165 for any of the boards. 6166 6167* Keep your modifications to the necessary minimum: A patch 6168 containing several unrelated changes or arbitrary reformats will be 6169 returned with a request to re-formatting / split it. 6170 6171* If you modify existing code, make sure that your new code does not 6172 add to the memory footprint of the code ;-) Small is beautiful! 6173 When adding new features, these should compile conditionally only 6174 (using #ifdef), and the resulting code with the new feature 6175 disabled must not need more memory than the old code without your 6176 modification. 6177 6178* Remember that there is a size limit of 100 kB per message on the 6179 u-boot mailing list. Bigger patches will be moderated. If they are 6180 reasonable and not too big, they will be acknowledged. But patches 6181 bigger than the size limit should be avoided. 6182