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_GENERIC_GLOBAL_DATA 455 Defines global data is initialized in generic board board_init_f(). 456 If this macro is defined, global data is created and cleared in 457 generic board board_init_f(). Without this macro, architecture/board 458 should initialize global data before calling board_init_f(). 459 460 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 461 462 Defines the endianess of the CPU. Implementation of those 463 values is arch specific. 464 465 CONFIG_SYS_FSL_DDR 466 Freescale DDR driver in use. This type of DDR controller is 467 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 468 SoCs. 469 470 CONFIG_SYS_FSL_DDR_ADDR 471 Freescale DDR memory-mapped register base. 472 473 CONFIG_SYS_FSL_DDR_EMU 474 Specify emulator support for DDR. Some DDR features such as 475 deskew training are not available. 476 477 CONFIG_SYS_FSL_DDRC_GEN1 478 Freescale DDR1 controller. 479 480 CONFIG_SYS_FSL_DDRC_GEN2 481 Freescale DDR2 controller. 482 483 CONFIG_SYS_FSL_DDRC_GEN3 484 Freescale DDR3 controller. 485 486 CONFIG_SYS_FSL_DDRC_GEN4 487 Freescale DDR4 controller. 488 489 CONFIG_SYS_FSL_DDRC_ARM_GEN3 490 Freescale DDR3 controller for ARM-based SoCs. 491 492 CONFIG_SYS_FSL_DDR1 493 Board config to use DDR1. It can be enabled for SoCs with 494 Freescale DDR1 or DDR2 controllers, depending on the board 495 implemetation. 496 497 CONFIG_SYS_FSL_DDR2 498 Board config to use DDR2. It can be eanbeld for SoCs with 499 Freescale DDR2 or DDR3 controllers, depending on the board 500 implementation. 501 502 CONFIG_SYS_FSL_DDR3 503 Board config to use DDR3. It can be enabled for SoCs with 504 Freescale DDR3 or DDR3L controllers. 505 506 CONFIG_SYS_FSL_DDR3L 507 Board config to use DDR3L. It can be enabled for SoCs with 508 DDR3L controllers. 509 510 CONFIG_SYS_FSL_DDR4 511 Board config to use DDR4. It can be enabled for SoCs with 512 DDR4 controllers. 513 514 CONFIG_SYS_FSL_IFC_BE 515 Defines the IFC controller register space as Big Endian 516 517 CONFIG_SYS_FSL_IFC_LE 518 Defines the IFC controller register space as Little Endian 519 520 CONFIG_SYS_FSL_PBL_PBI 521 It enables addition of RCW (Power on reset configuration) in built image. 522 Please refer doc/README.pblimage for more details 523 524 CONFIG_SYS_FSL_PBL_RCW 525 It adds PBI(pre-boot instructions) commands in u-boot build image. 526 PBI commands can be used to configure SoC before it starts the execution. 527 Please refer doc/README.pblimage for more details 528 529 CONFIG_SPL_FSL_PBL 530 It adds a target to create boot binary having SPL binary in PBI format 531 concatenated with u-boot binary. 532 533 CONFIG_SYS_FSL_DDR_BE 534 Defines the DDR controller register space as Big Endian 535 536 CONFIG_SYS_FSL_DDR_LE 537 Defines the DDR controller register space as Little Endian 538 539 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 540 Physical address from the view of DDR controllers. It is the 541 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 542 it could be different for ARM SoCs. 543 544 CONFIG_SYS_FSL_DDR_INTLV_256B 545 DDR controller interleaving on 256-byte. This is a special 546 interleaving mode, handled by Dickens for Freescale layerscape 547 SoCs with ARM core. 548 549- Intel Monahans options: 550 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 551 552 Defines the Monahans run mode to oscillator 553 ratio. Valid values are 8, 16, 24, 31. The core 554 frequency is this value multiplied by 13 MHz. 555 556 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 557 558 Defines the Monahans turbo mode to oscillator 559 ratio. Valid values are 1 (default if undefined) and 560 2. The core frequency as calculated above is multiplied 561 by this value. 562 563- MIPS CPU options: 564 CONFIG_SYS_INIT_SP_OFFSET 565 566 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 567 pointer. This is needed for the temporary stack before 568 relocation. 569 570 CONFIG_SYS_MIPS_CACHE_MODE 571 572 Cache operation mode for the MIPS CPU. 573 See also arch/mips/include/asm/mipsregs.h. 574 Possible values are: 575 CONF_CM_CACHABLE_NO_WA 576 CONF_CM_CACHABLE_WA 577 CONF_CM_UNCACHED 578 CONF_CM_CACHABLE_NONCOHERENT 579 CONF_CM_CACHABLE_CE 580 CONF_CM_CACHABLE_COW 581 CONF_CM_CACHABLE_CUW 582 CONF_CM_CACHABLE_ACCELERATED 583 584 CONFIG_SYS_XWAY_EBU_BOOTCFG 585 586 Special option for Lantiq XWAY SoCs for booting from NOR flash. 587 See also arch/mips/cpu/mips32/start.S. 588 589 CONFIG_XWAY_SWAP_BYTES 590 591 Enable compilation of tools/xway-swap-bytes needed for Lantiq 592 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 593 be swapped if a flash programmer is used. 594 595- ARM options: 596 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 597 598 Select high exception vectors of the ARM core, e.g., do not 599 clear the V bit of the c1 register of CP15. 600 601 CONFIG_SYS_THUMB_BUILD 602 603 Use this flag to build U-Boot using the Thumb instruction 604 set for ARM architectures. Thumb instruction set provides 605 better code density. For ARM architectures that support 606 Thumb2 this flag will result in Thumb2 code generated by 607 GCC. 608 609 CONFIG_ARM_ERRATA_716044 610 CONFIG_ARM_ERRATA_742230 611 CONFIG_ARM_ERRATA_743622 612 CONFIG_ARM_ERRATA_751472 613 CONFIG_ARM_ERRATA_794072 614 CONFIG_ARM_ERRATA_761320 615 616 If set, the workarounds for these ARM errata are applied early 617 during U-Boot startup. Note that these options force the 618 workarounds to be applied; no CPU-type/version detection 619 exists, unlike the similar options in the Linux kernel. Do not 620 set these options unless they apply! 621 622- CPU timer options: 623 CONFIG_SYS_HZ 624 625 The frequency of the timer returned by get_timer(). 626 get_timer() must operate in milliseconds and this CONFIG 627 option must be set to 1000. 628 629- Linux Kernel Interface: 630 CONFIG_CLOCKS_IN_MHZ 631 632 U-Boot stores all clock information in Hz 633 internally. For binary compatibility with older Linux 634 kernels (which expect the clocks passed in the 635 bd_info data to be in MHz) the environment variable 636 "clocks_in_mhz" can be defined so that U-Boot 637 converts clock data to MHZ before passing it to the 638 Linux kernel. 639 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 640 "clocks_in_mhz=1" is automatically included in the 641 default environment. 642 643 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 644 645 When transferring memsize parameter to linux, some versions 646 expect it to be in bytes, others in MB. 647 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 648 649 CONFIG_OF_LIBFDT 650 651 New kernel versions are expecting firmware settings to be 652 passed using flattened device trees (based on open firmware 653 concepts). 654 655 CONFIG_OF_LIBFDT 656 * New libfdt-based support 657 * Adds the "fdt" command 658 * The bootm command automatically updates the fdt 659 660 OF_CPU - The proper name of the cpus node (only required for 661 MPC512X and MPC5xxx based boards). 662 OF_SOC - The proper name of the soc node (only required for 663 MPC512X and MPC5xxx based boards). 664 OF_TBCLK - The timebase frequency. 665 OF_STDOUT_PATH - The path to the console device 666 667 boards with QUICC Engines require OF_QE to set UCC MAC 668 addresses 669 670 CONFIG_OF_BOARD_SETUP 671 672 Board code has addition modification that it wants to make 673 to the flat device tree before handing it off to the kernel 674 675 CONFIG_OF_BOOT_CPU 676 677 This define fills in the correct boot CPU in the boot 678 param header, the default value is zero if undefined. 679 680 CONFIG_OF_IDE_FIXUP 681 682 U-Boot can detect if an IDE device is present or not. 683 If not, and this new config option is activated, U-Boot 684 removes the ATA node from the DTS before booting Linux, 685 so the Linux IDE driver does not probe the device and 686 crash. This is needed for buggy hardware (uc101) where 687 no pull down resistor is connected to the signal IDE5V_DD7. 688 689 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 690 691 This setting is mandatory for all boards that have only one 692 machine type and must be used to specify the machine type 693 number as it appears in the ARM machine registry 694 (see http://www.arm.linux.org.uk/developer/machines/). 695 Only boards that have multiple machine types supported 696 in a single configuration file and the machine type is 697 runtime discoverable, do not have to use this setting. 698 699- vxWorks boot parameters: 700 701 bootvx constructs a valid bootline using the following 702 environments variables: bootfile, ipaddr, serverip, hostname. 703 It loads the vxWorks image pointed bootfile. 704 705 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 706 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 707 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 708 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 709 710 CONFIG_SYS_VXWORKS_ADD_PARAMS 711 712 Add it at the end of the bootline. E.g "u=username pw=secret" 713 714 Note: If a "bootargs" environment is defined, it will overwride 715 the defaults discussed just above. 716 717- Cache Configuration: 718 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 719 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 720 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 721 722- Cache Configuration for ARM: 723 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 724 controller 725 CONFIG_SYS_PL310_BASE - Physical base address of PL310 726 controller register space 727 728- Serial Ports: 729 CONFIG_PL010_SERIAL 730 731 Define this if you want support for Amba PrimeCell PL010 UARTs. 732 733 CONFIG_PL011_SERIAL 734 735 Define this if you want support for Amba PrimeCell PL011 UARTs. 736 737 CONFIG_PL011_CLOCK 738 739 If you have Amba PrimeCell PL011 UARTs, set this variable to 740 the clock speed of the UARTs. 741 742 CONFIG_PL01x_PORTS 743 744 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 745 define this to a list of base addresses for each (supported) 746 port. See e.g. include/configs/versatile.h 747 748 CONFIG_PL011_SERIAL_RLCR 749 750 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 751 have separate receive and transmit line control registers. Set 752 this variable to initialize the extra register. 753 754 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 755 756 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 757 boot loader that has already initialized the UART. Define this 758 variable to flush the UART at init time. 759 760 CONFIG_SERIAL_HW_FLOW_CONTROL 761 762 Define this variable to enable hw flow control in serial driver. 763 Current user of this option is drivers/serial/nsl16550.c driver 764 765- Console Interface: 766 Depending on board, define exactly one serial port 767 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 768 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 769 console by defining CONFIG_8xx_CONS_NONE 770 771 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 772 port routines must be defined elsewhere 773 (i.e. serial_init(), serial_getc(), ...) 774 775 CONFIG_CFB_CONSOLE 776 Enables console device for a color framebuffer. Needs following 777 defines (cf. smiLynxEM, i8042) 778 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 779 (default big endian) 780 VIDEO_HW_RECTFILL graphic chip supports 781 rectangle fill 782 (cf. smiLynxEM) 783 VIDEO_HW_BITBLT graphic chip supports 784 bit-blit (cf. smiLynxEM) 785 VIDEO_VISIBLE_COLS visible pixel columns 786 (cols=pitch) 787 VIDEO_VISIBLE_ROWS visible pixel rows 788 VIDEO_PIXEL_SIZE bytes per pixel 789 VIDEO_DATA_FORMAT graphic data format 790 (0-5, cf. cfb_console.c) 791 VIDEO_FB_ADRS framebuffer address 792 VIDEO_KBD_INIT_FCT keyboard int fct 793 (i.e. i8042_kbd_init()) 794 VIDEO_TSTC_FCT test char fct 795 (i.e. i8042_tstc) 796 VIDEO_GETC_FCT get char fct 797 (i.e. i8042_getc) 798 CONFIG_CONSOLE_CURSOR cursor drawing on/off 799 (requires blink timer 800 cf. i8042.c) 801 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 802 CONFIG_CONSOLE_TIME display time/date info in 803 upper right corner 804 (requires CONFIG_CMD_DATE) 805 CONFIG_VIDEO_LOGO display Linux logo in 806 upper left corner 807 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 808 linux_logo.h for logo. 809 Requires CONFIG_VIDEO_LOGO 810 CONFIG_CONSOLE_EXTRA_INFO 811 additional board info beside 812 the logo 813 814 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 815 a limited number of ANSI escape sequences (cursor control, 816 erase functions and limited graphics rendition control). 817 818 When CONFIG_CFB_CONSOLE is defined, video console is 819 default i/o. Serial console can be forced with 820 environment 'console=serial'. 821 822 When CONFIG_SILENT_CONSOLE is defined, all console 823 messages (by U-Boot and Linux!) can be silenced with 824 the "silent" environment variable. See 825 doc/README.silent for more information. 826 827 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 828 is 0x00. 829 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 830 is 0xa0. 831 832- Console Baudrate: 833 CONFIG_BAUDRATE - in bps 834 Select one of the baudrates listed in 835 CONFIG_SYS_BAUDRATE_TABLE, see below. 836 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 837 838- Console Rx buffer length 839 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 840 the maximum receive buffer length for the SMC. 841 This option is actual only for 82xx and 8xx possible. 842 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 843 must be defined, to setup the maximum idle timeout for 844 the SMC. 845 846- Pre-Console Buffer: 847 Prior to the console being initialised (i.e. serial UART 848 initialised etc) all console output is silently discarded. 849 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 850 buffer any console messages prior to the console being 851 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 852 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 853 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 854 bytes are output before the console is initialised, the 855 earlier bytes are discarded. 856 857 'Sane' compilers will generate smaller code if 858 CONFIG_PRE_CON_BUF_SZ is a power of 2 859 860- Safe printf() functions 861 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 862 the printf() functions. These are defined in 863 include/vsprintf.h and include snprintf(), vsnprintf() and 864 so on. Code size increase is approximately 300-500 bytes. 865 If this option is not given then these functions will 866 silently discard their buffer size argument - this means 867 you are not getting any overflow checking in this case. 868 869- Boot Delay: CONFIG_BOOTDELAY - in seconds 870 Delay before automatically booting the default image; 871 set to -1 to disable autoboot. 872 set to -2 to autoboot with no delay and not check for abort 873 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 874 875 See doc/README.autoboot for these options that 876 work with CONFIG_BOOTDELAY. None are required. 877 CONFIG_BOOT_RETRY_TIME 878 CONFIG_BOOT_RETRY_MIN 879 CONFIG_AUTOBOOT_KEYED 880 CONFIG_AUTOBOOT_PROMPT 881 CONFIG_AUTOBOOT_DELAY_STR 882 CONFIG_AUTOBOOT_STOP_STR 883 CONFIG_AUTOBOOT_DELAY_STR2 884 CONFIG_AUTOBOOT_STOP_STR2 885 CONFIG_ZERO_BOOTDELAY_CHECK 886 CONFIG_RESET_TO_RETRY 887 888- Autoboot Command: 889 CONFIG_BOOTCOMMAND 890 Only needed when CONFIG_BOOTDELAY is enabled; 891 define a command string that is automatically executed 892 when no character is read on the console interface 893 within "Boot Delay" after reset. 894 895 CONFIG_BOOTARGS 896 This can be used to pass arguments to the bootm 897 command. The value of CONFIG_BOOTARGS goes into the 898 environment value "bootargs". 899 900 CONFIG_RAMBOOT and CONFIG_NFSBOOT 901 The value of these goes into the environment as 902 "ramboot" and "nfsboot" respectively, and can be used 903 as a convenience, when switching between booting from 904 RAM and NFS. 905 906- Bootcount: 907 CONFIG_BOOTCOUNT_LIMIT 908 Implements a mechanism for detecting a repeating reboot 909 cycle, see: 910 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 911 912 CONFIG_BOOTCOUNT_ENV 913 If no softreset save registers are found on the hardware 914 "bootcount" is stored in the environment. To prevent a 915 saveenv on all reboots, the environment variable 916 "upgrade_available" is used. If "upgrade_available" is 917 0, "bootcount" is always 0, if "upgrade_available" is 918 1 "bootcount" is incremented in the environment. 919 So the Userspace Applikation must set the "upgrade_available" 920 and "bootcount" variable to 0, if a boot was successfully. 921 922- Pre-Boot Commands: 923 CONFIG_PREBOOT 924 925 When this option is #defined, the existence of the 926 environment variable "preboot" will be checked 927 immediately before starting the CONFIG_BOOTDELAY 928 countdown and/or running the auto-boot command resp. 929 entering interactive mode. 930 931 This feature is especially useful when "preboot" is 932 automatically generated or modified. For an example 933 see the LWMON board specific code: here "preboot" is 934 modified when the user holds down a certain 935 combination of keys on the (special) keyboard when 936 booting the systems 937 938- Serial Download Echo Mode: 939 CONFIG_LOADS_ECHO 940 If defined to 1, all characters received during a 941 serial download (using the "loads" command) are 942 echoed back. This might be needed by some terminal 943 emulations (like "cu"), but may as well just take 944 time on others. This setting #define's the initial 945 value of the "loads_echo" environment variable. 946 947- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 948 CONFIG_KGDB_BAUDRATE 949 Select one of the baudrates listed in 950 CONFIG_SYS_BAUDRATE_TABLE, see below. 951 952- Monitor Functions: 953 Monitor commands can be included or excluded 954 from the build by using the #include files 955 <config_cmd_all.h> and #undef'ing unwanted 956 commands, or using <config_cmd_default.h> 957 and augmenting with additional #define's 958 for wanted commands. 959 960 The default command configuration includes all commands 961 except those marked below with a "*". 962 963 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 964 CONFIG_CMD_ASKENV * ask for env variable 965 CONFIG_CMD_BDI bdinfo 966 CONFIG_CMD_BEDBUG * Include BedBug Debugger 967 CONFIG_CMD_BMP * BMP support 968 CONFIG_CMD_BSP * Board specific commands 969 CONFIG_CMD_BOOTD bootd 970 CONFIG_CMD_CACHE * icache, dcache 971 CONFIG_CMD_CLK * clock command support 972 CONFIG_CMD_CONSOLE coninfo 973 CONFIG_CMD_CRC32 * crc32 974 CONFIG_CMD_DATE * support for RTC, date/time... 975 CONFIG_CMD_DHCP * DHCP support 976 CONFIG_CMD_DIAG * Diagnostics 977 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 978 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 979 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 980 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 981 CONFIG_CMD_DTT * Digital Therm and Thermostat 982 CONFIG_CMD_ECHO echo arguments 983 CONFIG_CMD_EDITENV edit env variable 984 CONFIG_CMD_EEPROM * EEPROM read/write support 985 CONFIG_CMD_ELF * bootelf, bootvx 986 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 987 CONFIG_CMD_ENV_FLAGS * display details about env flags 988 CONFIG_CMD_ENV_EXISTS * check existence of env variable 989 CONFIG_CMD_EXPORTENV * export the environment 990 CONFIG_CMD_EXT2 * ext2 command support 991 CONFIG_CMD_EXT4 * ext4 command support 992 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 993 that work for multiple fs types 994 CONFIG_CMD_SAVEENV saveenv 995 CONFIG_CMD_FDC * Floppy Disk Support 996 CONFIG_CMD_FAT * FAT command support 997 CONFIG_CMD_FLASH flinfo, erase, protect 998 CONFIG_CMD_FPGA FPGA device initialization support 999 CONFIG_CMD_FUSE * Device fuse support 1000 CONFIG_CMD_GETTIME * Get time since boot 1001 CONFIG_CMD_GO * the 'go' command (exec code) 1002 CONFIG_CMD_GREPENV * search environment 1003 CONFIG_CMD_HASH * calculate hash / digest 1004 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 1005 CONFIG_CMD_I2C * I2C serial bus support 1006 CONFIG_CMD_IDE * IDE harddisk support 1007 CONFIG_CMD_IMI iminfo 1008 CONFIG_CMD_IMLS List all images found in NOR flash 1009 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 1010 CONFIG_CMD_IMMAP * IMMR dump support 1011 CONFIG_CMD_IMPORTENV * import an environment 1012 CONFIG_CMD_INI * import data from an ini file into the env 1013 CONFIG_CMD_IRQ * irqinfo 1014 CONFIG_CMD_ITEST Integer/string test of 2 values 1015 CONFIG_CMD_JFFS2 * JFFS2 Support 1016 CONFIG_CMD_KGDB * kgdb 1017 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 1018 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 1019 (169.254.*.*) 1020 CONFIG_CMD_LOADB loadb 1021 CONFIG_CMD_LOADS loads 1022 CONFIG_CMD_MD5SUM * print md5 message digest 1023 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1024 CONFIG_CMD_MEMINFO * Display detailed memory information 1025 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1026 loop, loopw 1027 CONFIG_CMD_MEMTEST * mtest 1028 CONFIG_CMD_MISC Misc functions like sleep etc 1029 CONFIG_CMD_MMC * MMC memory mapped support 1030 CONFIG_CMD_MII * MII utility commands 1031 CONFIG_CMD_MTDPARTS * MTD partition support 1032 CONFIG_CMD_NAND * NAND support 1033 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1034 CONFIG_CMD_NFS NFS support 1035 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1036 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1037 CONFIG_CMD_PCI * pciinfo 1038 CONFIG_CMD_PCMCIA * PCMCIA support 1039 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1040 host 1041 CONFIG_CMD_PORTIO * Port I/O 1042 CONFIG_CMD_READ * Read raw data from partition 1043 CONFIG_CMD_REGINFO * Register dump 1044 CONFIG_CMD_RUN run command in env variable 1045 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1046 CONFIG_CMD_SAVES * save S record dump 1047 CONFIG_CMD_SCSI * SCSI Support 1048 CONFIG_CMD_SDRAM * print SDRAM configuration information 1049 (requires CONFIG_CMD_I2C) 1050 CONFIG_CMD_SETGETDCR Support for DCR Register access 1051 (4xx only) 1052 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1053 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1054 (requires CONFIG_CMD_MEMORY) 1055 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1056 CONFIG_CMD_SOURCE "source" command Support 1057 CONFIG_CMD_SPI * SPI serial bus support 1058 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1059 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1060 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1061 CONFIG_CMD_TIMER * access to the system tick timer 1062 CONFIG_CMD_USB * USB support 1063 CONFIG_CMD_CDP * Cisco Discover Protocol support 1064 CONFIG_CMD_MFSL * Microblaze FSL support 1065 CONFIG_CMD_XIMG Load part of Multi Image 1066 CONFIG_CMD_UUID * Generate random UUID or GUID string 1067 1068 EXAMPLE: If you want all functions except of network 1069 support you can write: 1070 1071 #include "config_cmd_all.h" 1072 #undef CONFIG_CMD_NET 1073 1074 Other Commands: 1075 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1076 1077 Note: Don't enable the "icache" and "dcache" commands 1078 (configuration option CONFIG_CMD_CACHE) unless you know 1079 what you (and your U-Boot users) are doing. Data 1080 cache cannot be enabled on systems like the 8xx or 1081 8260 (where accesses to the IMMR region must be 1082 uncached), and it cannot be disabled on all other 1083 systems where we (mis-) use the data cache to hold an 1084 initial stack and some data. 1085 1086 1087 XXX - this list needs to get updated! 1088 1089- Regular expression support: 1090 CONFIG_REGEX 1091 If this variable is defined, U-Boot is linked against 1092 the SLRE (Super Light Regular Expression) library, 1093 which adds regex support to some commands, as for 1094 example "env grep" and "setexpr". 1095 1096- Device tree: 1097 CONFIG_OF_CONTROL 1098 If this variable is defined, U-Boot will use a device tree 1099 to configure its devices, instead of relying on statically 1100 compiled #defines in the board file. This option is 1101 experimental and only available on a few boards. The device 1102 tree is available in the global data as gd->fdt_blob. 1103 1104 U-Boot needs to get its device tree from somewhere. This can 1105 be done using one of the two options below: 1106 1107 CONFIG_OF_EMBED 1108 If this variable is defined, U-Boot will embed a device tree 1109 binary in its image. This device tree file should be in the 1110 board directory and called <soc>-<board>.dts. The binary file 1111 is then picked up in board_init_f() and made available through 1112 the global data structure as gd->blob. 1113 1114 CONFIG_OF_SEPARATE 1115 If this variable is defined, U-Boot will build a device tree 1116 binary. It will be called u-boot.dtb. Architecture-specific 1117 code will locate it at run-time. Generally this works by: 1118 1119 cat u-boot.bin u-boot.dtb >image.bin 1120 1121 and in fact, U-Boot does this for you, creating a file called 1122 u-boot-dtb.bin which is useful in the common case. You can 1123 still use the individual files if you need something more 1124 exotic. 1125 1126- Watchdog: 1127 CONFIG_WATCHDOG 1128 If this variable is defined, it enables watchdog 1129 support for the SoC. There must be support in the SoC 1130 specific code for a watchdog. For the 8xx and 8260 1131 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1132 register. When supported for a specific SoC is 1133 available, then no further board specific code should 1134 be needed to use it. 1135 1136 CONFIG_HW_WATCHDOG 1137 When using a watchdog circuitry external to the used 1138 SoC, then define this variable and provide board 1139 specific code for the "hw_watchdog_reset" function. 1140 1141- U-Boot Version: 1142 CONFIG_VERSION_VARIABLE 1143 If this variable is defined, an environment variable 1144 named "ver" is created by U-Boot showing the U-Boot 1145 version as printed by the "version" command. 1146 Any change to this variable will be reverted at the 1147 next reset. 1148 1149- Real-Time Clock: 1150 1151 When CONFIG_CMD_DATE is selected, the type of the RTC 1152 has to be selected, too. Define exactly one of the 1153 following options: 1154 1155 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1156 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1157 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1158 CONFIG_RTC_MC146818 - use MC146818 RTC 1159 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1160 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1161 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1162 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1163 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1164 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1165 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1166 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1167 RV3029 RTC. 1168 1169 Note that if the RTC uses I2C, then the I2C interface 1170 must also be configured. See I2C Support, below. 1171 1172- GPIO Support: 1173 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1174 1175 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1176 chip-ngpio pairs that tell the PCA953X driver the number of 1177 pins supported by a particular chip. 1178 1179 Note that if the GPIO device uses I2C, then the I2C interface 1180 must also be configured. See I2C Support, below. 1181 1182- Timestamp Support: 1183 1184 When CONFIG_TIMESTAMP is selected, the timestamp 1185 (date and time) of an image is printed by image 1186 commands like bootm or iminfo. This option is 1187 automatically enabled when you select CONFIG_CMD_DATE . 1188 1189- Partition Labels (disklabels) Supported: 1190 Zero or more of the following: 1191 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1192 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1193 Intel architecture, USB sticks, etc. 1194 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1195 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1196 bootloader. Note 2TB partition limit; see 1197 disk/part_efi.c 1198 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1199 1200 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1201 CONFIG_CMD_SCSI) you must configure support for at 1202 least one non-MTD partition type as well. 1203 1204- IDE Reset method: 1205 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1206 board configurations files but used nowhere! 1207 1208 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1209 be performed by calling the function 1210 ide_set_reset(int reset) 1211 which has to be defined in a board specific file 1212 1213- ATAPI Support: 1214 CONFIG_ATAPI 1215 1216 Set this to enable ATAPI support. 1217 1218- LBA48 Support 1219 CONFIG_LBA48 1220 1221 Set this to enable support for disks larger than 137GB 1222 Also look at CONFIG_SYS_64BIT_LBA. 1223 Whithout these , LBA48 support uses 32bit variables and will 'only' 1224 support disks up to 2.1TB. 1225 1226 CONFIG_SYS_64BIT_LBA: 1227 When enabled, makes the IDE subsystem use 64bit sector addresses. 1228 Default is 32bit. 1229 1230- SCSI Support: 1231 At the moment only there is only support for the 1232 SYM53C8XX SCSI controller; define 1233 CONFIG_SCSI_SYM53C8XX to enable it. 1234 1235 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1236 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1237 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1238 maximum numbers of LUNs, SCSI ID's and target 1239 devices. 1240 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1241 1242 The environment variable 'scsidevs' is set to the number of 1243 SCSI devices found during the last scan. 1244 1245- NETWORK Support (PCI): 1246 CONFIG_E1000 1247 Support for Intel 8254x/8257x gigabit chips. 1248 1249 CONFIG_E1000_SPI 1250 Utility code for direct access to the SPI bus on Intel 8257x. 1251 This does not do anything useful unless you set at least one 1252 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1253 1254 CONFIG_E1000_SPI_GENERIC 1255 Allow generic access to the SPI bus on the Intel 8257x, for 1256 example with the "sspi" command. 1257 1258 CONFIG_CMD_E1000 1259 Management command for E1000 devices. When used on devices 1260 with SPI support you can reprogram the EEPROM from U-Boot. 1261 1262 CONFIG_E1000_FALLBACK_MAC 1263 default MAC for empty EEPROM after production. 1264 1265 CONFIG_EEPRO100 1266 Support for Intel 82557/82559/82559ER chips. 1267 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1268 write routine for first time initialisation. 1269 1270 CONFIG_TULIP 1271 Support for Digital 2114x chips. 1272 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1273 modem chip initialisation (KS8761/QS6611). 1274 1275 CONFIG_NATSEMI 1276 Support for National dp83815 chips. 1277 1278 CONFIG_NS8382X 1279 Support for National dp8382[01] gigabit chips. 1280 1281- NETWORK Support (other): 1282 1283 CONFIG_DRIVER_AT91EMAC 1284 Support for AT91RM9200 EMAC. 1285 1286 CONFIG_RMII 1287 Define this to use reduced MII inteface 1288 1289 CONFIG_DRIVER_AT91EMAC_QUIET 1290 If this defined, the driver is quiet. 1291 The driver doen't show link status messages. 1292 1293 CONFIG_CALXEDA_XGMAC 1294 Support for the Calxeda XGMAC device 1295 1296 CONFIG_LAN91C96 1297 Support for SMSC's LAN91C96 chips. 1298 1299 CONFIG_LAN91C96_BASE 1300 Define this to hold the physical address 1301 of the LAN91C96's I/O space 1302 1303 CONFIG_LAN91C96_USE_32_BIT 1304 Define this to enable 32 bit addressing 1305 1306 CONFIG_SMC91111 1307 Support for SMSC's LAN91C111 chip 1308 1309 CONFIG_SMC91111_BASE 1310 Define this to hold the physical address 1311 of the device (I/O space) 1312 1313 CONFIG_SMC_USE_32_BIT 1314 Define this if data bus is 32 bits 1315 1316 CONFIG_SMC_USE_IOFUNCS 1317 Define this to use i/o functions instead of macros 1318 (some hardware wont work with macros) 1319 1320 CONFIG_DRIVER_TI_EMAC 1321 Support for davinci emac 1322 1323 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1324 Define this if you have more then 3 PHYs. 1325 1326 CONFIG_FTGMAC100 1327 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1328 1329 CONFIG_FTGMAC100_EGIGA 1330 Define this to use GE link update with gigabit PHY. 1331 Define this if FTGMAC100 is connected to gigabit PHY. 1332 If your system has 10/100 PHY only, it might not occur 1333 wrong behavior. Because PHY usually return timeout or 1334 useless data when polling gigabit status and gigabit 1335 control registers. This behavior won't affect the 1336 correctnessof 10/100 link speed update. 1337 1338 CONFIG_SMC911X 1339 Support for SMSC's LAN911x and LAN921x chips 1340 1341 CONFIG_SMC911X_BASE 1342 Define this to hold the physical address 1343 of the device (I/O space) 1344 1345 CONFIG_SMC911X_32_BIT 1346 Define this if data bus is 32 bits 1347 1348 CONFIG_SMC911X_16_BIT 1349 Define this if data bus is 16 bits. If your processor 1350 automatically converts one 32 bit word to two 16 bit 1351 words you may also try CONFIG_SMC911X_32_BIT. 1352 1353 CONFIG_SH_ETHER 1354 Support for Renesas on-chip Ethernet controller 1355 1356 CONFIG_SH_ETHER_USE_PORT 1357 Define the number of ports to be used 1358 1359 CONFIG_SH_ETHER_PHY_ADDR 1360 Define the ETH PHY's address 1361 1362 CONFIG_SH_ETHER_CACHE_WRITEBACK 1363 If this option is set, the driver enables cache flush. 1364 1365- TPM Support: 1366 CONFIG_TPM 1367 Support TPM devices. 1368 1369 CONFIG_TPM_TIS_I2C 1370 Support for i2c bus TPM devices. Only one device 1371 per system is supported at this time. 1372 1373 CONFIG_TPM_TIS_I2C_BUS_NUMBER 1374 Define the the i2c bus number for the TPM device 1375 1376 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS 1377 Define the TPM's address on the i2c bus 1378 1379 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1380 Define the burst count bytes upper limit 1381 1382 CONFIG_TPM_ATMEL_TWI 1383 Support for Atmel TWI TPM device. Requires I2C support. 1384 1385 CONFIG_TPM_TIS_LPC 1386 Support for generic parallel port TPM devices. Only one device 1387 per system is supported at this time. 1388 1389 CONFIG_TPM_TIS_BASE_ADDRESS 1390 Base address where the generic TPM device is mapped 1391 to. Contemporary x86 systems usually map it at 1392 0xfed40000. 1393 1394 CONFIG_CMD_TPM 1395 Add tpm monitor functions. 1396 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1397 provides monitor access to authorized functions. 1398 1399 CONFIG_TPM 1400 Define this to enable the TPM support library which provides 1401 functional interfaces to some TPM commands. 1402 Requires support for a TPM device. 1403 1404 CONFIG_TPM_AUTH_SESSIONS 1405 Define this to enable authorized functions in the TPM library. 1406 Requires CONFIG_TPM and CONFIG_SHA1. 1407 1408- USB Support: 1409 At the moment only the UHCI host controller is 1410 supported (PIP405, MIP405, MPC5200); define 1411 CONFIG_USB_UHCI to enable it. 1412 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1413 and define CONFIG_USB_STORAGE to enable the USB 1414 storage devices. 1415 Note: 1416 Supported are USB Keyboards and USB Floppy drives 1417 (TEAC FD-05PUB). 1418 MPC5200 USB requires additional defines: 1419 CONFIG_USB_CLOCK 1420 for 528 MHz Clock: 0x0001bbbb 1421 CONFIG_PSC3_USB 1422 for USB on PSC3 1423 CONFIG_USB_CONFIG 1424 for differential drivers: 0x00001000 1425 for single ended drivers: 0x00005000 1426 for differential drivers on PSC3: 0x00000100 1427 for single ended drivers on PSC3: 0x00004100 1428 CONFIG_SYS_USB_EVENT_POLL 1429 May be defined to allow interrupt polling 1430 instead of using asynchronous interrupts 1431 1432 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1433 txfilltuning field in the EHCI controller on reset. 1434 1435 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum 1436 interval for usb hub power-on delay.(minimum 100msec) 1437 1438- USB Device: 1439 Define the below if you wish to use the USB console. 1440 Once firmware is rebuilt from a serial console issue the 1441 command "setenv stdin usbtty; setenv stdout usbtty" and 1442 attach your USB cable. The Unix command "dmesg" should print 1443 it has found a new device. The environment variable usbtty 1444 can be set to gserial or cdc_acm to enable your device to 1445 appear to a USB host as a Linux gserial device or a 1446 Common Device Class Abstract Control Model serial device. 1447 If you select usbtty = gserial you should be able to enumerate 1448 a Linux host by 1449 # modprobe usbserial vendor=0xVendorID product=0xProductID 1450 else if using cdc_acm, simply setting the environment 1451 variable usbtty to be cdc_acm should suffice. The following 1452 might be defined in YourBoardName.h 1453 1454 CONFIG_USB_DEVICE 1455 Define this to build a UDC device 1456 1457 CONFIG_USB_TTY 1458 Define this to have a tty type of device available to 1459 talk to the UDC device 1460 1461 CONFIG_USBD_HS 1462 Define this to enable the high speed support for usb 1463 device and usbtty. If this feature is enabled, a routine 1464 int is_usbd_high_speed(void) 1465 also needs to be defined by the driver to dynamically poll 1466 whether the enumeration has succeded at high speed or full 1467 speed. 1468 1469 CONFIG_SYS_CONSOLE_IS_IN_ENV 1470 Define this if you want stdin, stdout &/or stderr to 1471 be set to usbtty. 1472 1473 mpc8xx: 1474 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1475 Derive USB clock from external clock "blah" 1476 - CONFIG_SYS_USB_EXTC_CLK 0x02 1477 1478 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1479 Derive USB clock from brgclk 1480 - CONFIG_SYS_USB_BRG_CLK 0x04 1481 1482 If you have a USB-IF assigned VendorID then you may wish to 1483 define your own vendor specific values either in BoardName.h 1484 or directly in usbd_vendor_info.h. If you don't define 1485 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1486 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1487 should pretend to be a Linux device to it's target host. 1488 1489 CONFIG_USBD_MANUFACTURER 1490 Define this string as the name of your company for 1491 - CONFIG_USBD_MANUFACTURER "my company" 1492 1493 CONFIG_USBD_PRODUCT_NAME 1494 Define this string as the name of your product 1495 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1496 1497 CONFIG_USBD_VENDORID 1498 Define this as your assigned Vendor ID from the USB 1499 Implementors Forum. This *must* be a genuine Vendor ID 1500 to avoid polluting the USB namespace. 1501 - CONFIG_USBD_VENDORID 0xFFFF 1502 1503 CONFIG_USBD_PRODUCTID 1504 Define this as the unique Product ID 1505 for your device 1506 - CONFIG_USBD_PRODUCTID 0xFFFF 1507 1508- ULPI Layer Support: 1509 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1510 the generic ULPI layer. The generic layer accesses the ULPI PHY 1511 via the platform viewport, so you need both the genric layer and 1512 the viewport enabled. Currently only Chipidea/ARC based 1513 viewport is supported. 1514 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1515 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1516 If your ULPI phy needs a different reference clock than the 1517 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1518 the appropriate value in Hz. 1519 1520- MMC Support: 1521 The MMC controller on the Intel PXA is supported. To 1522 enable this define CONFIG_MMC. The MMC can be 1523 accessed from the boot prompt by mapping the device 1524 to physical memory similar to flash. Command line is 1525 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1526 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1527 1528 CONFIG_SH_MMCIF 1529 Support for Renesas on-chip MMCIF controller 1530 1531 CONFIG_SH_MMCIF_ADDR 1532 Define the base address of MMCIF registers 1533 1534 CONFIG_SH_MMCIF_CLK 1535 Define the clock frequency for MMCIF 1536 1537 CONFIG_GENERIC_MMC 1538 Enable the generic MMC driver 1539 1540 CONFIG_SUPPORT_EMMC_BOOT 1541 Enable some additional features of the eMMC boot partitions. 1542 1543 CONFIG_SUPPORT_EMMC_RPMB 1544 Enable the commands for reading, writing and programming the 1545 key for the Replay Protection Memory Block partition in eMMC. 1546 1547- USB Device Firmware Update (DFU) class support: 1548 CONFIG_DFU_FUNCTION 1549 This enables the USB portion of the DFU USB class 1550 1551 CONFIG_CMD_DFU 1552 This enables the command "dfu" which is used to have 1553 U-Boot create a DFU class device via USB. This command 1554 requires that the "dfu_alt_info" environment variable be 1555 set and define the alt settings to expose to the host. 1556 1557 CONFIG_DFU_MMC 1558 This enables support for exposing (e)MMC devices via DFU. 1559 1560 CONFIG_DFU_NAND 1561 This enables support for exposing NAND devices via DFU. 1562 1563 CONFIG_DFU_RAM 1564 This enables support for exposing RAM via DFU. 1565 Note: DFU spec refer to non-volatile memory usage, but 1566 allow usages beyond the scope of spec - here RAM usage, 1567 one that would help mostly the developer. 1568 1569 CONFIG_SYS_DFU_DATA_BUF_SIZE 1570 Dfu transfer uses a buffer before writing data to the 1571 raw storage device. Make the size (in bytes) of this buffer 1572 configurable. The size of this buffer is also configurable 1573 through the "dfu_bufsiz" environment variable. 1574 1575 CONFIG_SYS_DFU_MAX_FILE_SIZE 1576 When updating files rather than the raw storage device, 1577 we use a static buffer to copy the file into and then write 1578 the buffer once we've been given the whole file. Define 1579 this to the maximum filesize (in bytes) for the buffer. 1580 Default is 4 MiB if undefined. 1581 1582 DFU_DEFAULT_POLL_TIMEOUT 1583 Poll timeout [ms], is the timeout a device can send to the 1584 host. The host must wait for this timeout before sending 1585 a subsequent DFU_GET_STATUS request to the device. 1586 1587 DFU_MANIFEST_POLL_TIMEOUT 1588 Poll timeout [ms], which the device sends to the host when 1589 entering dfuMANIFEST state. Host waits this timeout, before 1590 sending again an USB request to the device. 1591 1592- Journaling Flash filesystem support: 1593 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1594 CONFIG_JFFS2_NAND_DEV 1595 Define these for a default partition on a NAND device 1596 1597 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1598 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1599 Define these for a default partition on a NOR device 1600 1601 CONFIG_SYS_JFFS_CUSTOM_PART 1602 Define this to create an own partition. You have to provide a 1603 function struct part_info* jffs2_part_info(int part_num) 1604 1605 If you define only one JFFS2 partition you may also want to 1606 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1607 to disable the command chpart. This is the default when you 1608 have not defined a custom partition 1609 1610- FAT(File Allocation Table) filesystem write function support: 1611 CONFIG_FAT_WRITE 1612 1613 Define this to enable support for saving memory data as a 1614 file in FAT formatted partition. 1615 1616 This will also enable the command "fatwrite" enabling the 1617 user to write files to FAT. 1618 1619CBFS (Coreboot Filesystem) support 1620 CONFIG_CMD_CBFS 1621 1622 Define this to enable support for reading from a Coreboot 1623 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1624 and cbfsload. 1625 1626- Keyboard Support: 1627 CONFIG_ISA_KEYBOARD 1628 1629 Define this to enable standard (PC-Style) keyboard 1630 support 1631 1632 CONFIG_I8042_KBD 1633 Standard PC keyboard driver with US (is default) and 1634 GERMAN key layout (switch via environment 'keymap=de') support. 1635 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1636 for cfb_console. Supports cursor blinking. 1637 1638 CONFIG_CROS_EC_KEYB 1639 Enables a Chrome OS keyboard using the CROS_EC interface. 1640 This uses CROS_EC to communicate with a second microcontroller 1641 which provides key scans on request. 1642 1643- Video support: 1644 CONFIG_VIDEO 1645 1646 Define this to enable video support (for output to 1647 video). 1648 1649 CONFIG_VIDEO_CT69000 1650 1651 Enable Chips & Technologies 69000 Video chip 1652 1653 CONFIG_VIDEO_SMI_LYNXEM 1654 Enable Silicon Motion SMI 712/710/810 Video chip. The 1655 video output is selected via environment 'videoout' 1656 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1657 assumed. 1658 1659 For the CT69000 and SMI_LYNXEM drivers, videomode is 1660 selected via environment 'videomode'. Two different ways 1661 are possible: 1662 - "videomode=num" 'num' is a standard LiLo mode numbers. 1663 Following standard modes are supported (* is default): 1664 1665 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1666 -------------+--------------------------------------------- 1667 8 bits | 0x301* 0x303 0x305 0x161 0x307 1668 15 bits | 0x310 0x313 0x316 0x162 0x319 1669 16 bits | 0x311 0x314 0x317 0x163 0x31A 1670 24 bits | 0x312 0x315 0x318 ? 0x31B 1671 -------------+--------------------------------------------- 1672 (i.e. setenv videomode 317; saveenv; reset;) 1673 1674 - "videomode=bootargs" all the video parameters are parsed 1675 from the bootargs. (See drivers/video/videomodes.c) 1676 1677 1678 CONFIG_VIDEO_SED13806 1679 Enable Epson SED13806 driver. This driver supports 8bpp 1680 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1681 or CONFIG_VIDEO_SED13806_16BPP 1682 1683 CONFIG_FSL_DIU_FB 1684 Enable the Freescale DIU video driver. Reference boards for 1685 SOCs that have a DIU should define this macro to enable DIU 1686 support, and should also define these other macros: 1687 1688 CONFIG_SYS_DIU_ADDR 1689 CONFIG_VIDEO 1690 CONFIG_CMD_BMP 1691 CONFIG_CFB_CONSOLE 1692 CONFIG_VIDEO_SW_CURSOR 1693 CONFIG_VGA_AS_SINGLE_DEVICE 1694 CONFIG_VIDEO_LOGO 1695 CONFIG_VIDEO_BMP_LOGO 1696 1697 The DIU driver will look for the 'video-mode' environment 1698 variable, and if defined, enable the DIU as a console during 1699 boot. See the documentation file README.video for a 1700 description of this variable. 1701 1702 CONFIG_VIDEO_VGA 1703 1704 Enable the VGA video / BIOS for x86. The alternative if you 1705 are using coreboot is to use the coreboot frame buffer 1706 driver. 1707 1708 1709- Keyboard Support: 1710 CONFIG_KEYBOARD 1711 1712 Define this to enable a custom keyboard support. 1713 This simply calls drv_keyboard_init() which must be 1714 defined in your board-specific files. 1715 The only board using this so far is RBC823. 1716 1717- LCD Support: CONFIG_LCD 1718 1719 Define this to enable LCD support (for output to LCD 1720 display); also select one of the supported displays 1721 by defining one of these: 1722 1723 CONFIG_ATMEL_LCD: 1724 1725 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1726 1727 CONFIG_NEC_NL6448AC33: 1728 1729 NEC NL6448AC33-18. Active, color, single scan. 1730 1731 CONFIG_NEC_NL6448BC20 1732 1733 NEC NL6448BC20-08. 6.5", 640x480. 1734 Active, color, single scan. 1735 1736 CONFIG_NEC_NL6448BC33_54 1737 1738 NEC NL6448BC33-54. 10.4", 640x480. 1739 Active, color, single scan. 1740 1741 CONFIG_SHARP_16x9 1742 1743 Sharp 320x240. Active, color, single scan. 1744 It isn't 16x9, and I am not sure what it is. 1745 1746 CONFIG_SHARP_LQ64D341 1747 1748 Sharp LQ64D341 display, 640x480. 1749 Active, color, single scan. 1750 1751 CONFIG_HLD1045 1752 1753 HLD1045 display, 640x480. 1754 Active, color, single scan. 1755 1756 CONFIG_OPTREX_BW 1757 1758 Optrex CBL50840-2 NF-FW 99 22 M5 1759 or 1760 Hitachi LMG6912RPFC-00T 1761 or 1762 Hitachi SP14Q002 1763 1764 320x240. Black & white. 1765 1766 Normally display is black on white background; define 1767 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1768 1769 CONFIG_LCD_ALIGNMENT 1770 1771 Normally the LCD is page-aligned (tyically 4KB). If this is 1772 defined then the LCD will be aligned to this value instead. 1773 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1774 here, since it is cheaper to change data cache settings on 1775 a per-section basis. 1776 1777 CONFIG_CONSOLE_SCROLL_LINES 1778 1779 When the console need to be scrolled, this is the number of 1780 lines to scroll by. It defaults to 1. Increasing this makes 1781 the console jump but can help speed up operation when scrolling 1782 is slow. 1783 1784 CONFIG_LCD_BMP_RLE8 1785 1786 Support drawing of RLE8-compressed bitmaps on the LCD. 1787 1788 CONFIG_I2C_EDID 1789 1790 Enables an 'i2c edid' command which can read EDID 1791 information over I2C from an attached LCD display. 1792 1793- Splash Screen Support: CONFIG_SPLASH_SCREEN 1794 1795 If this option is set, the environment is checked for 1796 a variable "splashimage". If found, the usual display 1797 of logo, copyright and system information on the LCD 1798 is suppressed and the BMP image at the address 1799 specified in "splashimage" is loaded instead. The 1800 console is redirected to the "nulldev", too. This 1801 allows for a "silent" boot where a splash screen is 1802 loaded very quickly after power-on. 1803 1804 CONFIG_SPLASHIMAGE_GUARD 1805 1806 If this option is set, then U-Boot will prevent the environment 1807 variable "splashimage" from being set to a problematic address 1808 (see README.displaying-bmps). 1809 This option is useful for targets where, due to alignment 1810 restrictions, an improperly aligned BMP image will cause a data 1811 abort. If you think you will not have problems with unaligned 1812 accesses (for example because your toolchain prevents them) 1813 there is no need to set this option. 1814 1815 CONFIG_SPLASH_SCREEN_ALIGN 1816 1817 If this option is set the splash image can be freely positioned 1818 on the screen. Environment variable "splashpos" specifies the 1819 position as "x,y". If a positive number is given it is used as 1820 number of pixel from left/top. If a negative number is given it 1821 is used as number of pixel from right/bottom. You can also 1822 specify 'm' for centering the image. 1823 1824 Example: 1825 setenv splashpos m,m 1826 => image at center of screen 1827 1828 setenv splashpos 30,20 1829 => image at x = 30 and y = 20 1830 1831 setenv splashpos -10,m 1832 => vertically centered image 1833 at x = dspWidth - bmpWidth - 9 1834 1835- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1836 1837 If this option is set, additionally to standard BMP 1838 images, gzipped BMP images can be displayed via the 1839 splashscreen support or the bmp command. 1840 1841- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1842 1843 If this option is set, 8-bit RLE compressed BMP images 1844 can be displayed via the splashscreen support or the 1845 bmp command. 1846 1847- Do compresssing for memory range: 1848 CONFIG_CMD_ZIP 1849 1850 If this option is set, it would use zlib deflate method 1851 to compress the specified memory at its best effort. 1852 1853- Compression support: 1854 CONFIG_GZIP 1855 1856 Enabled by default to support gzip compressed images. 1857 1858 CONFIG_BZIP2 1859 1860 If this option is set, support for bzip2 compressed 1861 images is included. If not, only uncompressed and gzip 1862 compressed images are supported. 1863 1864 NOTE: the bzip2 algorithm requires a lot of RAM, so 1865 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1866 be at least 4MB. 1867 1868 CONFIG_LZMA 1869 1870 If this option is set, support for lzma compressed 1871 images is included. 1872 1873 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1874 requires an amount of dynamic memory that is given by the 1875 formula: 1876 1877 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1878 1879 Where lc and lp stand for, respectively, Literal context bits 1880 and Literal pos bits. 1881 1882 This value is upper-bounded by 14MB in the worst case. Anyway, 1883 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1884 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1885 a very small buffer. 1886 1887 Use the lzmainfo tool to determinate the lc and lp values and 1888 then calculate the amount of needed dynamic memory (ensuring 1889 the appropriate CONFIG_SYS_MALLOC_LEN value). 1890 1891 CONFIG_LZO 1892 1893 If this option is set, support for LZO compressed images 1894 is included. 1895 1896- MII/PHY support: 1897 CONFIG_PHY_ADDR 1898 1899 The address of PHY on MII bus. 1900 1901 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1902 1903 The clock frequency of the MII bus 1904 1905 CONFIG_PHY_GIGE 1906 1907 If this option is set, support for speed/duplex 1908 detection of gigabit PHY is included. 1909 1910 CONFIG_PHY_RESET_DELAY 1911 1912 Some PHY like Intel LXT971A need extra delay after 1913 reset before any MII register access is possible. 1914 For such PHY, set this option to the usec delay 1915 required. (minimum 300usec for LXT971A) 1916 1917 CONFIG_PHY_CMD_DELAY (ppc4xx) 1918 1919 Some PHY like Intel LXT971A need extra delay after 1920 command issued before MII status register can be read 1921 1922- Ethernet address: 1923 CONFIG_ETHADDR 1924 CONFIG_ETH1ADDR 1925 CONFIG_ETH2ADDR 1926 CONFIG_ETH3ADDR 1927 CONFIG_ETH4ADDR 1928 CONFIG_ETH5ADDR 1929 1930 Define a default value for Ethernet address to use 1931 for the respective Ethernet interface, in case this 1932 is not determined automatically. 1933 1934- IP address: 1935 CONFIG_IPADDR 1936 1937 Define a default value for the IP address to use for 1938 the default Ethernet interface, in case this is not 1939 determined through e.g. bootp. 1940 (Environment variable "ipaddr") 1941 1942- Server IP address: 1943 CONFIG_SERVERIP 1944 1945 Defines a default value for the IP address of a TFTP 1946 server to contact when using the "tftboot" command. 1947 (Environment variable "serverip") 1948 1949 CONFIG_KEEP_SERVERADDR 1950 1951 Keeps the server's MAC address, in the env 'serveraddr' 1952 for passing to bootargs (like Linux's netconsole option) 1953 1954- Gateway IP address: 1955 CONFIG_GATEWAYIP 1956 1957 Defines a default value for the IP address of the 1958 default router where packets to other networks are 1959 sent to. 1960 (Environment variable "gatewayip") 1961 1962- Subnet mask: 1963 CONFIG_NETMASK 1964 1965 Defines a default value for the subnet mask (or 1966 routing prefix) which is used to determine if an IP 1967 address belongs to the local subnet or needs to be 1968 forwarded through a router. 1969 (Environment variable "netmask") 1970 1971- Multicast TFTP Mode: 1972 CONFIG_MCAST_TFTP 1973 1974 Defines whether you want to support multicast TFTP as per 1975 rfc-2090; for example to work with atftp. Lets lots of targets 1976 tftp down the same boot image concurrently. Note: the Ethernet 1977 driver in use must provide a function: mcast() to join/leave a 1978 multicast group. 1979 1980- BOOTP Recovery Mode: 1981 CONFIG_BOOTP_RANDOM_DELAY 1982 1983 If you have many targets in a network that try to 1984 boot using BOOTP, you may want to avoid that all 1985 systems send out BOOTP requests at precisely the same 1986 moment (which would happen for instance at recovery 1987 from a power failure, when all systems will try to 1988 boot, thus flooding the BOOTP server. Defining 1989 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1990 inserted before sending out BOOTP requests. The 1991 following delays are inserted then: 1992 1993 1st BOOTP request: delay 0 ... 1 sec 1994 2nd BOOTP request: delay 0 ... 2 sec 1995 3rd BOOTP request: delay 0 ... 4 sec 1996 4th and following 1997 BOOTP requests: delay 0 ... 8 sec 1998 1999- DHCP Advanced Options: 2000 You can fine tune the DHCP functionality by defining 2001 CONFIG_BOOTP_* symbols: 2002 2003 CONFIG_BOOTP_SUBNETMASK 2004 CONFIG_BOOTP_GATEWAY 2005 CONFIG_BOOTP_HOSTNAME 2006 CONFIG_BOOTP_NISDOMAIN 2007 CONFIG_BOOTP_BOOTPATH 2008 CONFIG_BOOTP_BOOTFILESIZE 2009 CONFIG_BOOTP_DNS 2010 CONFIG_BOOTP_DNS2 2011 CONFIG_BOOTP_SEND_HOSTNAME 2012 CONFIG_BOOTP_NTPSERVER 2013 CONFIG_BOOTP_TIMEOFFSET 2014 CONFIG_BOOTP_VENDOREX 2015 CONFIG_BOOTP_MAY_FAIL 2016 2017 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2018 environment variable, not the BOOTP server. 2019 2020 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2021 after the configured retry count, the call will fail 2022 instead of starting over. This can be used to fail over 2023 to Link-local IP address configuration if the DHCP server 2024 is not available. 2025 2026 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2027 serverip from a DHCP server, it is possible that more 2028 than one DNS serverip is offered to the client. 2029 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2030 serverip will be stored in the additional environment 2031 variable "dnsip2". The first DNS serverip is always 2032 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2033 is defined. 2034 2035 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2036 to do a dynamic update of a DNS server. To do this, they 2037 need the hostname of the DHCP requester. 2038 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2039 of the "hostname" environment variable is passed as 2040 option 12 to the DHCP server. 2041 2042 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2043 2044 A 32bit value in microseconds for a delay between 2045 receiving a "DHCP Offer" and sending the "DHCP Request". 2046 This fixes a problem with certain DHCP servers that don't 2047 respond 100% of the time to a "DHCP request". E.g. On an 2048 AT91RM9200 processor running at 180MHz, this delay needed 2049 to be *at least* 15,000 usec before a Windows Server 2003 2050 DHCP server would reply 100% of the time. I recommend at 2051 least 50,000 usec to be safe. The alternative is to hope 2052 that one of the retries will be successful but note that 2053 the DHCP timeout and retry process takes a longer than 2054 this delay. 2055 2056 - Link-local IP address negotiation: 2057 Negotiate with other link-local clients on the local network 2058 for an address that doesn't require explicit configuration. 2059 This is especially useful if a DHCP server cannot be guaranteed 2060 to exist in all environments that the device must operate. 2061 2062 See doc/README.link-local for more information. 2063 2064 - CDP Options: 2065 CONFIG_CDP_DEVICE_ID 2066 2067 The device id used in CDP trigger frames. 2068 2069 CONFIG_CDP_DEVICE_ID_PREFIX 2070 2071 A two character string which is prefixed to the MAC address 2072 of the device. 2073 2074 CONFIG_CDP_PORT_ID 2075 2076 A printf format string which contains the ascii name of 2077 the port. Normally is set to "eth%d" which sets 2078 eth0 for the first Ethernet, eth1 for the second etc. 2079 2080 CONFIG_CDP_CAPABILITIES 2081 2082 A 32bit integer which indicates the device capabilities; 2083 0x00000010 for a normal host which does not forwards. 2084 2085 CONFIG_CDP_VERSION 2086 2087 An ascii string containing the version of the software. 2088 2089 CONFIG_CDP_PLATFORM 2090 2091 An ascii string containing the name of the platform. 2092 2093 CONFIG_CDP_TRIGGER 2094 2095 A 32bit integer sent on the trigger. 2096 2097 CONFIG_CDP_POWER_CONSUMPTION 2098 2099 A 16bit integer containing the power consumption of the 2100 device in .1 of milliwatts. 2101 2102 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2103 2104 A byte containing the id of the VLAN. 2105 2106- Status LED: CONFIG_STATUS_LED 2107 2108 Several configurations allow to display the current 2109 status using a LED. For instance, the LED will blink 2110 fast while running U-Boot code, stop blinking as 2111 soon as a reply to a BOOTP request was received, and 2112 start blinking slow once the Linux kernel is running 2113 (supported by a status LED driver in the Linux 2114 kernel). Defining CONFIG_STATUS_LED enables this 2115 feature in U-Boot. 2116 2117 Additional options: 2118 2119 CONFIG_GPIO_LED 2120 The status LED can be connected to a GPIO pin. 2121 In such cases, the gpio_led driver can be used as a 2122 status LED backend implementation. Define CONFIG_GPIO_LED 2123 to include the gpio_led driver in the U-Boot binary. 2124 2125 CONFIG_GPIO_LED_INVERTED_TABLE 2126 Some GPIO connected LEDs may have inverted polarity in which 2127 case the GPIO high value corresponds to LED off state and 2128 GPIO low value corresponds to LED on state. 2129 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2130 with a list of GPIO LEDs that have inverted polarity. 2131 2132- CAN Support: CONFIG_CAN_DRIVER 2133 2134 Defining CONFIG_CAN_DRIVER enables CAN driver support 2135 on those systems that support this (optional) 2136 feature, like the TQM8xxL modules. 2137 2138- I2C Support: CONFIG_SYS_I2C 2139 2140 This enable the NEW i2c subsystem, and will allow you to use 2141 i2c commands at the u-boot command line (as long as you set 2142 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2143 based realtime clock chips or other i2c devices. See 2144 common/cmd_i2c.c for a description of the command line 2145 interface. 2146 2147 ported i2c driver to the new framework: 2148 - drivers/i2c/soft_i2c.c: 2149 - activate first bus with CONFIG_SYS_I2C_SOFT define 2150 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2151 for defining speed and slave address 2152 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2153 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2154 for defining speed and slave address 2155 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2156 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2157 for defining speed and slave address 2158 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2159 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2160 for defining speed and slave address 2161 2162 - drivers/i2c/fsl_i2c.c: 2163 - activate i2c driver with CONFIG_SYS_I2C_FSL 2164 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2165 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2166 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2167 bus. 2168 - If your board supports a second fsl i2c bus, define 2169 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2170 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2171 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2172 second bus. 2173 2174 - drivers/i2c/tegra_i2c.c: 2175 - activate this driver with CONFIG_SYS_I2C_TEGRA 2176 - This driver adds 4 i2c buses with a fix speed from 2177 100000 and the slave addr 0! 2178 2179 - drivers/i2c/ppc4xx_i2c.c 2180 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2181 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2182 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2183 2184 - drivers/i2c/i2c_mxc.c 2185 - activate this driver with CONFIG_SYS_I2C_MXC 2186 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2187 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2188 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2189 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2190 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2191 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2192 If thoses defines are not set, default value is 100000 2193 for speed, and 0 for slave. 2194 2195 - drivers/i2c/rcar_i2c.c: 2196 - activate this driver with CONFIG_SYS_I2C_RCAR 2197 - This driver adds 4 i2c buses 2198 2199 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2200 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2201 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2202 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2203 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2204 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2205 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2206 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2207 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2208 2209 - drivers/i2c/sh_i2c.c: 2210 - activate this driver with CONFIG_SYS_I2C_SH 2211 - This driver adds from 2 to 5 i2c buses 2212 2213 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2214 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2215 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2216 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2217 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2218 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2219 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2220 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2221 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2222 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2223 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2224 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2225 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses 2226 2227 - drivers/i2c/omap24xx_i2c.c 2228 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2229 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2230 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2231 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2232 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2233 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2234 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2235 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2236 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2237 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2238 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2239 2240 - drivers/i2c/zynq_i2c.c 2241 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2242 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2243 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2244 2245 - drivers/i2c/s3c24x0_i2c.c: 2246 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2247 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2248 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2249 with a fix speed from 100000 and the slave addr 0! 2250 2251 additional defines: 2252 2253 CONFIG_SYS_NUM_I2C_BUSES 2254 Hold the number of i2c busses you want to use. If you 2255 don't use/have i2c muxes on your i2c bus, this 2256 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2257 omit this define. 2258 2259 CONFIG_SYS_I2C_DIRECT_BUS 2260 define this, if you don't use i2c muxes on your hardware. 2261 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2262 omit this define. 2263 2264 CONFIG_SYS_I2C_MAX_HOPS 2265 define how many muxes are maximal consecutively connected 2266 on one i2c bus. If you not use i2c muxes, omit this 2267 define. 2268 2269 CONFIG_SYS_I2C_BUSES 2270 hold a list of busses you want to use, only used if 2271 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2272 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2273 CONFIG_SYS_NUM_I2C_BUSES = 9: 2274 2275 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2276 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2277 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2278 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2279 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2280 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2281 {1, {I2C_NULL_HOP}}, \ 2282 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2283 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2284 } 2285 2286 which defines 2287 bus 0 on adapter 0 without a mux 2288 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2289 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2290 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2291 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2292 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2293 bus 6 on adapter 1 without a mux 2294 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2295 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2296 2297 If you do not have i2c muxes on your board, omit this define. 2298 2299- Legacy I2C Support: CONFIG_HARD_I2C 2300 2301 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2302 provides the following compelling advantages: 2303 2304 - more than one i2c adapter is usable 2305 - approved multibus support 2306 - better i2c mux support 2307 2308 ** Please consider updating your I2C driver now. ** 2309 2310 These enable legacy I2C serial bus commands. Defining 2311 CONFIG_HARD_I2C will include the appropriate I2C driver 2312 for the selected CPU. 2313 2314 This will allow you to use i2c commands at the u-boot 2315 command line (as long as you set CONFIG_CMD_I2C in 2316 CONFIG_COMMANDS) and communicate with i2c based realtime 2317 clock chips. See common/cmd_i2c.c for a description of the 2318 command line interface. 2319 2320 CONFIG_HARD_I2C selects a hardware I2C controller. 2321 2322 There are several other quantities that must also be 2323 defined when you define CONFIG_HARD_I2C. 2324 2325 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2326 to be the frequency (in Hz) at which you wish your i2c bus 2327 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2328 the CPU's i2c node address). 2329 2330 Now, the u-boot i2c code for the mpc8xx 2331 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2332 and so its address should therefore be cleared to 0 (See, 2333 eg, MPC823e User's Manual p.16-473). So, set 2334 CONFIG_SYS_I2C_SLAVE to 0. 2335 2336 CONFIG_SYS_I2C_INIT_MPC5XXX 2337 2338 When a board is reset during an i2c bus transfer 2339 chips might think that the current transfer is still 2340 in progress. Reset the slave devices by sending start 2341 commands until the slave device responds. 2342 2343 That's all that's required for CONFIG_HARD_I2C. 2344 2345 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2346 then the following macros need to be defined (examples are 2347 from include/configs/lwmon.h): 2348 2349 I2C_INIT 2350 2351 (Optional). Any commands necessary to enable the I2C 2352 controller or configure ports. 2353 2354 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2355 2356 I2C_PORT 2357 2358 (Only for MPC8260 CPU). The I/O port to use (the code 2359 assumes both bits are on the same port). Valid values 2360 are 0..3 for ports A..D. 2361 2362 I2C_ACTIVE 2363 2364 The code necessary to make the I2C data line active 2365 (driven). If the data line is open collector, this 2366 define can be null. 2367 2368 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2369 2370 I2C_TRISTATE 2371 2372 The code necessary to make the I2C data line tri-stated 2373 (inactive). If the data line is open collector, this 2374 define can be null. 2375 2376 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2377 2378 I2C_READ 2379 2380 Code that returns true if the I2C data line is high, 2381 false if it is low. 2382 2383 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2384 2385 I2C_SDA(bit) 2386 2387 If <bit> is true, sets the I2C data line high. If it 2388 is false, it clears it (low). 2389 2390 eg: #define I2C_SDA(bit) \ 2391 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2392 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2393 2394 I2C_SCL(bit) 2395 2396 If <bit> is true, sets the I2C clock line high. If it 2397 is false, it clears it (low). 2398 2399 eg: #define I2C_SCL(bit) \ 2400 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2401 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2402 2403 I2C_DELAY 2404 2405 This delay is invoked four times per clock cycle so this 2406 controls the rate of data transfer. The data rate thus 2407 is 1 / (I2C_DELAY * 4). Often defined to be something 2408 like: 2409 2410 #define I2C_DELAY udelay(2) 2411 2412 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2413 2414 If your arch supports the generic GPIO framework (asm/gpio.h), 2415 then you may alternatively define the two GPIOs that are to be 2416 used as SCL / SDA. Any of the previous I2C_xxx macros will 2417 have GPIO-based defaults assigned to them as appropriate. 2418 2419 You should define these to the GPIO value as given directly to 2420 the generic GPIO functions. 2421 2422 CONFIG_SYS_I2C_INIT_BOARD 2423 2424 When a board is reset during an i2c bus transfer 2425 chips might think that the current transfer is still 2426 in progress. On some boards it is possible to access 2427 the i2c SCLK line directly, either by using the 2428 processor pin as a GPIO or by having a second pin 2429 connected to the bus. If this option is defined a 2430 custom i2c_init_board() routine in boards/xxx/board.c 2431 is run early in the boot sequence. 2432 2433 CONFIG_SYS_I2C_BOARD_LATE_INIT 2434 2435 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2436 defined a custom i2c_board_late_init() routine in 2437 boards/xxx/board.c is run AFTER the operations in i2c_init() 2438 is completed. This callpoint can be used to unreset i2c bus 2439 using CPU i2c controller register accesses for CPUs whose i2c 2440 controller provide such a method. It is called at the end of 2441 i2c_init() to allow i2c_init operations to setup the i2c bus 2442 controller on the CPU (e.g. setting bus speed & slave address). 2443 2444 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2445 2446 This option enables configuration of bi_iic_fast[] flags 2447 in u-boot bd_info structure based on u-boot environment 2448 variable "i2cfast". (see also i2cfast) 2449 2450 CONFIG_I2C_MULTI_BUS 2451 2452 This option allows the use of multiple I2C buses, each of which 2453 must have a controller. At any point in time, only one bus is 2454 active. To switch to a different bus, use the 'i2c dev' command. 2455 Note that bus numbering is zero-based. 2456 2457 CONFIG_SYS_I2C_NOPROBES 2458 2459 This option specifies a list of I2C devices that will be skipped 2460 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2461 is set, specify a list of bus-device pairs. Otherwise, specify 2462 a 1D array of device addresses 2463 2464 e.g. 2465 #undef CONFIG_I2C_MULTI_BUS 2466 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2467 2468 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2469 2470 #define CONFIG_I2C_MULTI_BUS 2471 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2472 2473 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2474 2475 CONFIG_SYS_SPD_BUS_NUM 2476 2477 If defined, then this indicates the I2C bus number for DDR SPD. 2478 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2479 2480 CONFIG_SYS_RTC_BUS_NUM 2481 2482 If defined, then this indicates the I2C bus number for the RTC. 2483 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2484 2485 CONFIG_SYS_DTT_BUS_NUM 2486 2487 If defined, then this indicates the I2C bus number for the DTT. 2488 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2489 2490 CONFIG_SYS_I2C_DTT_ADDR: 2491 2492 If defined, specifies the I2C address of the DTT device. 2493 If not defined, then U-Boot uses predefined value for 2494 specified DTT device. 2495 2496 CONFIG_SOFT_I2C_READ_REPEATED_START 2497 2498 defining this will force the i2c_read() function in 2499 the soft_i2c driver to perform an I2C repeated start 2500 between writing the address pointer and reading the 2501 data. If this define is omitted the default behaviour 2502 of doing a stop-start sequence will be used. Most I2C 2503 devices can use either method, but some require one or 2504 the other. 2505 2506- SPI Support: CONFIG_SPI 2507 2508 Enables SPI driver (so far only tested with 2509 SPI EEPROM, also an instance works with Crystal A/D and 2510 D/As on the SACSng board) 2511 2512 CONFIG_SH_SPI 2513 2514 Enables the driver for SPI controller on SuperH. Currently 2515 only SH7757 is supported. 2516 2517 CONFIG_SPI_X 2518 2519 Enables extended (16-bit) SPI EEPROM addressing. 2520 (symmetrical to CONFIG_I2C_X) 2521 2522 CONFIG_SOFT_SPI 2523 2524 Enables a software (bit-bang) SPI driver rather than 2525 using hardware support. This is a general purpose 2526 driver that only requires three general I/O port pins 2527 (two outputs, one input) to function. If this is 2528 defined, the board configuration must define several 2529 SPI configuration items (port pins to use, etc). For 2530 an example, see include/configs/sacsng.h. 2531 2532 CONFIG_HARD_SPI 2533 2534 Enables a hardware SPI driver for general-purpose reads 2535 and writes. As with CONFIG_SOFT_SPI, the board configuration 2536 must define a list of chip-select function pointers. 2537 Currently supported on some MPC8xxx processors. For an 2538 example, see include/configs/mpc8349emds.h. 2539 2540 CONFIG_MXC_SPI 2541 2542 Enables the driver for the SPI controllers on i.MX and MXC 2543 SoCs. Currently i.MX31/35/51 are supported. 2544 2545- FPGA Support: CONFIG_FPGA 2546 2547 Enables FPGA subsystem. 2548 2549 CONFIG_FPGA_<vendor> 2550 2551 Enables support for specific chip vendors. 2552 (ALTERA, XILINX) 2553 2554 CONFIG_FPGA_<family> 2555 2556 Enables support for FPGA family. 2557 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2558 2559 CONFIG_FPGA_COUNT 2560 2561 Specify the number of FPGA devices to support. 2562 2563 CONFIG_SYS_FPGA_PROG_FEEDBACK 2564 2565 Enable printing of hash marks during FPGA configuration. 2566 2567 CONFIG_SYS_FPGA_CHECK_BUSY 2568 2569 Enable checks on FPGA configuration interface busy 2570 status by the configuration function. This option 2571 will require a board or device specific function to 2572 be written. 2573 2574 CONFIG_FPGA_DELAY 2575 2576 If defined, a function that provides delays in the FPGA 2577 configuration driver. 2578 2579 CONFIG_SYS_FPGA_CHECK_CTRLC 2580 Allow Control-C to interrupt FPGA configuration 2581 2582 CONFIG_SYS_FPGA_CHECK_ERROR 2583 2584 Check for configuration errors during FPGA bitfile 2585 loading. For example, abort during Virtex II 2586 configuration if the INIT_B line goes low (which 2587 indicated a CRC error). 2588 2589 CONFIG_SYS_FPGA_WAIT_INIT 2590 2591 Maximum time to wait for the INIT_B line to deassert 2592 after PROB_B has been deasserted during a Virtex II 2593 FPGA configuration sequence. The default time is 500 2594 ms. 2595 2596 CONFIG_SYS_FPGA_WAIT_BUSY 2597 2598 Maximum time to wait for BUSY to deassert during 2599 Virtex II FPGA configuration. The default is 5 ms. 2600 2601 CONFIG_SYS_FPGA_WAIT_CONFIG 2602 2603 Time to wait after FPGA configuration. The default is 2604 200 ms. 2605 2606- Configuration Management: 2607 CONFIG_IDENT_STRING 2608 2609 If defined, this string will be added to the U-Boot 2610 version information (U_BOOT_VERSION) 2611 2612- Vendor Parameter Protection: 2613 2614 U-Boot considers the values of the environment 2615 variables "serial#" (Board Serial Number) and 2616 "ethaddr" (Ethernet Address) to be parameters that 2617 are set once by the board vendor / manufacturer, and 2618 protects these variables from casual modification by 2619 the user. Once set, these variables are read-only, 2620 and write or delete attempts are rejected. You can 2621 change this behaviour: 2622 2623 If CONFIG_ENV_OVERWRITE is #defined in your config 2624 file, the write protection for vendor parameters is 2625 completely disabled. Anybody can change or delete 2626 these parameters. 2627 2628 Alternatively, if you #define _both_ CONFIG_ETHADDR 2629 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2630 Ethernet address is installed in the environment, 2631 which can be changed exactly ONCE by the user. [The 2632 serial# is unaffected by this, i. e. it remains 2633 read-only.] 2634 2635 The same can be accomplished in a more flexible way 2636 for any variable by configuring the type of access 2637 to allow for those variables in the ".flags" variable 2638 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2639 2640- Protected RAM: 2641 CONFIG_PRAM 2642 2643 Define this variable to enable the reservation of 2644 "protected RAM", i. e. RAM which is not overwritten 2645 by U-Boot. Define CONFIG_PRAM to hold the number of 2646 kB you want to reserve for pRAM. You can overwrite 2647 this default value by defining an environment 2648 variable "pram" to the number of kB you want to 2649 reserve. Note that the board info structure will 2650 still show the full amount of RAM. If pRAM is 2651 reserved, a new environment variable "mem" will 2652 automatically be defined to hold the amount of 2653 remaining RAM in a form that can be passed as boot 2654 argument to Linux, for instance like that: 2655 2656 setenv bootargs ... mem=\${mem} 2657 saveenv 2658 2659 This way you can tell Linux not to use this memory, 2660 either, which results in a memory region that will 2661 not be affected by reboots. 2662 2663 *WARNING* If your board configuration uses automatic 2664 detection of the RAM size, you must make sure that 2665 this memory test is non-destructive. So far, the 2666 following board configurations are known to be 2667 "pRAM-clean": 2668 2669 IVMS8, IVML24, SPD8xx, TQM8xxL, 2670 HERMES, IP860, RPXlite, LWMON, 2671 FLAGADM, TQM8260 2672 2673- Access to physical memory region (> 4GB) 2674 Some basic support is provided for operations on memory not 2675 normally accessible to U-Boot - e.g. some architectures 2676 support access to more than 4GB of memory on 32-bit 2677 machines using physical address extension or similar. 2678 Define CONFIG_PHYSMEM to access this basic support, which 2679 currently only supports clearing the memory. 2680 2681- Error Recovery: 2682 CONFIG_PANIC_HANG 2683 2684 Define this variable to stop the system in case of a 2685 fatal error, so that you have to reset it manually. 2686 This is probably NOT a good idea for an embedded 2687 system where you want the system to reboot 2688 automatically as fast as possible, but it may be 2689 useful during development since you can try to debug 2690 the conditions that lead to the situation. 2691 2692 CONFIG_NET_RETRY_COUNT 2693 2694 This variable defines the number of retries for 2695 network operations like ARP, RARP, TFTP, or BOOTP 2696 before giving up the operation. If not defined, a 2697 default value of 5 is used. 2698 2699 CONFIG_ARP_TIMEOUT 2700 2701 Timeout waiting for an ARP reply in milliseconds. 2702 2703 CONFIG_NFS_TIMEOUT 2704 2705 Timeout in milliseconds used in NFS protocol. 2706 If you encounter "ERROR: Cannot umount" in nfs command, 2707 try longer timeout such as 2708 #define CONFIG_NFS_TIMEOUT 10000UL 2709 2710- Command Interpreter: 2711 CONFIG_AUTO_COMPLETE 2712 2713 Enable auto completion of commands using TAB. 2714 2715 Note that this feature has NOT been implemented yet 2716 for the "hush" shell. 2717 2718 2719 CONFIG_SYS_HUSH_PARSER 2720 2721 Define this variable to enable the "hush" shell (from 2722 Busybox) as command line interpreter, thus enabling 2723 powerful command line syntax like 2724 if...then...else...fi conditionals or `&&' and '||' 2725 constructs ("shell scripts"). 2726 2727 If undefined, you get the old, much simpler behaviour 2728 with a somewhat smaller memory footprint. 2729 2730 2731 CONFIG_SYS_PROMPT_HUSH_PS2 2732 2733 This defines the secondary prompt string, which is 2734 printed when the command interpreter needs more input 2735 to complete a command. Usually "> ". 2736 2737 Note: 2738 2739 In the current implementation, the local variables 2740 space and global environment variables space are 2741 separated. Local variables are those you define by 2742 simply typing `name=value'. To access a local 2743 variable later on, you have write `$name' or 2744 `${name}'; to execute the contents of a variable 2745 directly type `$name' at the command prompt. 2746 2747 Global environment variables are those you use 2748 setenv/printenv to work with. To run a command stored 2749 in such a variable, you need to use the run command, 2750 and you must not use the '$' sign to access them. 2751 2752 To store commands and special characters in a 2753 variable, please use double quotation marks 2754 surrounding the whole text of the variable, instead 2755 of the backslashes before semicolons and special 2756 symbols. 2757 2758- Commandline Editing and History: 2759 CONFIG_CMDLINE_EDITING 2760 2761 Enable editing and History functions for interactive 2762 commandline input operations 2763 2764- Default Environment: 2765 CONFIG_EXTRA_ENV_SETTINGS 2766 2767 Define this to contain any number of null terminated 2768 strings (variable = value pairs) that will be part of 2769 the default environment compiled into the boot image. 2770 2771 For example, place something like this in your 2772 board's config file: 2773 2774 #define CONFIG_EXTRA_ENV_SETTINGS \ 2775 "myvar1=value1\0" \ 2776 "myvar2=value2\0" 2777 2778 Warning: This method is based on knowledge about the 2779 internal format how the environment is stored by the 2780 U-Boot code. This is NOT an official, exported 2781 interface! Although it is unlikely that this format 2782 will change soon, there is no guarantee either. 2783 You better know what you are doing here. 2784 2785 Note: overly (ab)use of the default environment is 2786 discouraged. Make sure to check other ways to preset 2787 the environment like the "source" command or the 2788 boot command first. 2789 2790 CONFIG_ENV_VARS_UBOOT_CONFIG 2791 2792 Define this in order to add variables describing the 2793 U-Boot build configuration to the default environment. 2794 These will be named arch, cpu, board, vendor, and soc. 2795 2796 Enabling this option will cause the following to be defined: 2797 2798 - CONFIG_SYS_ARCH 2799 - CONFIG_SYS_CPU 2800 - CONFIG_SYS_BOARD 2801 - CONFIG_SYS_VENDOR 2802 - CONFIG_SYS_SOC 2803 2804 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2805 2806 Define this in order to add variables describing certain 2807 run-time determined information about the hardware to the 2808 environment. These will be named board_name, board_rev. 2809 2810 CONFIG_DELAY_ENVIRONMENT 2811 2812 Normally the environment is loaded when the board is 2813 intialised so that it is available to U-Boot. This inhibits 2814 that so that the environment is not available until 2815 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2816 this is instead controlled by the value of 2817 /config/load-environment. 2818 2819- DataFlash Support: 2820 CONFIG_HAS_DATAFLASH 2821 2822 Defining this option enables DataFlash features and 2823 allows to read/write in Dataflash via the standard 2824 commands cp, md... 2825 2826- Serial Flash support 2827 CONFIG_CMD_SF 2828 2829 Defining this option enables SPI flash commands 2830 'sf probe/read/write/erase/update'. 2831 2832 Usage requires an initial 'probe' to define the serial 2833 flash parameters, followed by read/write/erase/update 2834 commands. 2835 2836 The following defaults may be provided by the platform 2837 to handle the common case when only a single serial 2838 flash is present on the system. 2839 2840 CONFIG_SF_DEFAULT_BUS Bus identifier 2841 CONFIG_SF_DEFAULT_CS Chip-select 2842 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2843 CONFIG_SF_DEFAULT_SPEED in Hz 2844 2845 CONFIG_CMD_SF_TEST 2846 2847 Define this option to include a destructive SPI flash 2848 test ('sf test'). 2849 2850 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg 2851 2852 Define this option to use the Bank addr/Extended addr 2853 support on SPI flashes which has size > 16Mbytes. 2854 2855 CONFIG_SF_DUAL_FLASH Dual flash memories 2856 2857 Define this option to use dual flash support where two flash 2858 memories can be connected with a given cs line. 2859 currently Xilinx Zynq qspi support these type of connections. 2860 2861- SystemACE Support: 2862 CONFIG_SYSTEMACE 2863 2864 Adding this option adds support for Xilinx SystemACE 2865 chips attached via some sort of local bus. The address 2866 of the chip must also be defined in the 2867 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2868 2869 #define CONFIG_SYSTEMACE 2870 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2871 2872 When SystemACE support is added, the "ace" device type 2873 becomes available to the fat commands, i.e. fatls. 2874 2875- TFTP Fixed UDP Port: 2876 CONFIG_TFTP_PORT 2877 2878 If this is defined, the environment variable tftpsrcp 2879 is used to supply the TFTP UDP source port value. 2880 If tftpsrcp isn't defined, the normal pseudo-random port 2881 number generator is used. 2882 2883 Also, the environment variable tftpdstp is used to supply 2884 the TFTP UDP destination port value. If tftpdstp isn't 2885 defined, the normal port 69 is used. 2886 2887 The purpose for tftpsrcp is to allow a TFTP server to 2888 blindly start the TFTP transfer using the pre-configured 2889 target IP address and UDP port. This has the effect of 2890 "punching through" the (Windows XP) firewall, allowing 2891 the remainder of the TFTP transfer to proceed normally. 2892 A better solution is to properly configure the firewall, 2893 but sometimes that is not allowed. 2894 2895- Hashing support: 2896 CONFIG_CMD_HASH 2897 2898 This enables a generic 'hash' command which can produce 2899 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2900 2901 CONFIG_HASH_VERIFY 2902 2903 Enable the hash verify command (hash -v). This adds to code 2904 size a little. 2905 2906 CONFIG_SHA1 - support SHA1 hashing 2907 CONFIG_SHA256 - support SHA256 hashing 2908 2909 Note: There is also a sha1sum command, which should perhaps 2910 be deprecated in favour of 'hash sha1'. 2911 2912- Freescale i.MX specific commands: 2913 CONFIG_CMD_HDMIDETECT 2914 This enables 'hdmidet' command which returns true if an 2915 HDMI monitor is detected. This command is i.MX 6 specific. 2916 2917 CONFIG_CMD_BMODE 2918 This enables the 'bmode' (bootmode) command for forcing 2919 a boot from specific media. 2920 2921 This is useful for forcing the ROM's usb downloader to 2922 activate upon a watchdog reset which is nice when iterating 2923 on U-Boot. Using the reset button or running bmode normal 2924 will set it back to normal. This command currently 2925 supports i.MX53 and i.MX6. 2926 2927- Signing support: 2928 CONFIG_RSA 2929 2930 This enables the RSA algorithm used for FIT image verification 2931 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 2932 2933 The signing part is build into mkimage regardless of this 2934 option. 2935 2936- bootcount support: 2937 CONFIG_BOOTCOUNT_LIMIT 2938 2939 This enables the bootcounter support, see: 2940 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2941 2942 CONFIG_AT91SAM9XE 2943 enable special bootcounter support on at91sam9xe based boards. 2944 CONFIG_BLACKFIN 2945 enable special bootcounter support on blackfin based boards. 2946 CONFIG_SOC_DA8XX 2947 enable special bootcounter support on da850 based boards. 2948 CONFIG_BOOTCOUNT_RAM 2949 enable support for the bootcounter in RAM 2950 CONFIG_BOOTCOUNT_I2C 2951 enable support for the bootcounter on an i2c (like RTC) device. 2952 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2953 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2954 the bootcounter. 2955 CONFIG_BOOTCOUNT_ALEN = address len 2956 2957- Show boot progress: 2958 CONFIG_SHOW_BOOT_PROGRESS 2959 2960 Defining this option allows to add some board- 2961 specific code (calling a user-provided function 2962 "show_boot_progress(int)") that enables you to show 2963 the system's boot progress on some display (for 2964 example, some LED's) on your board. At the moment, 2965 the following checkpoints are implemented: 2966 2967- Detailed boot stage timing 2968 CONFIG_BOOTSTAGE 2969 Define this option to get detailed timing of each stage 2970 of the boot process. 2971 2972 CONFIG_BOOTSTAGE_USER_COUNT 2973 This is the number of available user bootstage records. 2974 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 2975 a new ID will be allocated from this stash. If you exceed 2976 the limit, recording will stop. 2977 2978 CONFIG_BOOTSTAGE_REPORT 2979 Define this to print a report before boot, similar to this: 2980 2981 Timer summary in microseconds: 2982 Mark Elapsed Stage 2983 0 0 reset 2984 3,575,678 3,575,678 board_init_f start 2985 3,575,695 17 arch_cpu_init A9 2986 3,575,777 82 arch_cpu_init done 2987 3,659,598 83,821 board_init_r start 2988 3,910,375 250,777 main_loop 2989 29,916,167 26,005,792 bootm_start 2990 30,361,327 445,160 start_kernel 2991 2992 CONFIG_CMD_BOOTSTAGE 2993 Add a 'bootstage' command which supports printing a report 2994 and un/stashing of bootstage data. 2995 2996 CONFIG_BOOTSTAGE_FDT 2997 Stash the bootstage information in the FDT. A root 'bootstage' 2998 node is created with each bootstage id as a child. Each child 2999 has a 'name' property and either 'mark' containing the 3000 mark time in microsecond, or 'accum' containing the 3001 accumulated time for that bootstage id in microseconds. 3002 For example: 3003 3004 bootstage { 3005 154 { 3006 name = "board_init_f"; 3007 mark = <3575678>; 3008 }; 3009 170 { 3010 name = "lcd"; 3011 accum = <33482>; 3012 }; 3013 }; 3014 3015 Code in the Linux kernel can find this in /proc/devicetree. 3016 3017Legacy uImage format: 3018 3019 Arg Where When 3020 1 common/cmd_bootm.c before attempting to boot an image 3021 -1 common/cmd_bootm.c Image header has bad magic number 3022 2 common/cmd_bootm.c Image header has correct magic number 3023 -2 common/cmd_bootm.c Image header has bad checksum 3024 3 common/cmd_bootm.c Image header has correct checksum 3025 -3 common/cmd_bootm.c Image data has bad checksum 3026 4 common/cmd_bootm.c Image data has correct checksum 3027 -4 common/cmd_bootm.c Image is for unsupported architecture 3028 5 common/cmd_bootm.c Architecture check OK 3029 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3030 6 common/cmd_bootm.c Image Type check OK 3031 -6 common/cmd_bootm.c gunzip uncompression error 3032 -7 common/cmd_bootm.c Unimplemented compression type 3033 7 common/cmd_bootm.c Uncompression OK 3034 8 common/cmd_bootm.c No uncompress/copy overwrite error 3035 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3036 3037 9 common/image.c Start initial ramdisk verification 3038 -10 common/image.c Ramdisk header has bad magic number 3039 -11 common/image.c Ramdisk header has bad checksum 3040 10 common/image.c Ramdisk header is OK 3041 -12 common/image.c Ramdisk data has bad checksum 3042 11 common/image.c Ramdisk data has correct checksum 3043 12 common/image.c Ramdisk verification complete, start loading 3044 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3045 13 common/image.c Start multifile image verification 3046 14 common/image.c No initial ramdisk, no multifile, continue. 3047 3048 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3049 3050 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3051 -31 post/post.c POST test failed, detected by post_output_backlog() 3052 -32 post/post.c POST test failed, detected by post_run_single() 3053 3054 34 common/cmd_doc.c before loading a Image from a DOC device 3055 -35 common/cmd_doc.c Bad usage of "doc" command 3056 35 common/cmd_doc.c correct usage of "doc" command 3057 -36 common/cmd_doc.c No boot device 3058 36 common/cmd_doc.c correct boot device 3059 -37 common/cmd_doc.c Unknown Chip ID on boot device 3060 37 common/cmd_doc.c correct chip ID found, device available 3061 -38 common/cmd_doc.c Read Error on boot device 3062 38 common/cmd_doc.c reading Image header from DOC device OK 3063 -39 common/cmd_doc.c Image header has bad magic number 3064 39 common/cmd_doc.c Image header has correct magic number 3065 -40 common/cmd_doc.c Error reading Image from DOC device 3066 40 common/cmd_doc.c Image header has correct magic number 3067 41 common/cmd_ide.c before loading a Image from a IDE device 3068 -42 common/cmd_ide.c Bad usage of "ide" command 3069 42 common/cmd_ide.c correct usage of "ide" command 3070 -43 common/cmd_ide.c No boot device 3071 43 common/cmd_ide.c boot device found 3072 -44 common/cmd_ide.c Device not available 3073 44 common/cmd_ide.c Device available 3074 -45 common/cmd_ide.c wrong partition selected 3075 45 common/cmd_ide.c partition selected 3076 -46 common/cmd_ide.c Unknown partition table 3077 46 common/cmd_ide.c valid partition table found 3078 -47 common/cmd_ide.c Invalid partition type 3079 47 common/cmd_ide.c correct partition type 3080 -48 common/cmd_ide.c Error reading Image Header on boot device 3081 48 common/cmd_ide.c reading Image Header from IDE device OK 3082 -49 common/cmd_ide.c Image header has bad magic number 3083 49 common/cmd_ide.c Image header has correct magic number 3084 -50 common/cmd_ide.c Image header has bad checksum 3085 50 common/cmd_ide.c Image header has correct checksum 3086 -51 common/cmd_ide.c Error reading Image from IDE device 3087 51 common/cmd_ide.c reading Image from IDE device OK 3088 52 common/cmd_nand.c before loading a Image from a NAND device 3089 -53 common/cmd_nand.c Bad usage of "nand" command 3090 53 common/cmd_nand.c correct usage of "nand" command 3091 -54 common/cmd_nand.c No boot device 3092 54 common/cmd_nand.c boot device found 3093 -55 common/cmd_nand.c Unknown Chip ID on boot device 3094 55 common/cmd_nand.c correct chip ID found, device available 3095 -56 common/cmd_nand.c Error reading Image Header on boot device 3096 56 common/cmd_nand.c reading Image Header from NAND device OK 3097 -57 common/cmd_nand.c Image header has bad magic number 3098 57 common/cmd_nand.c Image header has correct magic number 3099 -58 common/cmd_nand.c Error reading Image from NAND device 3100 58 common/cmd_nand.c reading Image from NAND device OK 3101 3102 -60 common/env_common.c Environment has a bad CRC, using default 3103 3104 64 net/eth.c starting with Ethernet configuration. 3105 -64 net/eth.c no Ethernet found. 3106 65 net/eth.c Ethernet found. 3107 3108 -80 common/cmd_net.c usage wrong 3109 80 common/cmd_net.c before calling NetLoop() 3110 -81 common/cmd_net.c some error in NetLoop() occurred 3111 81 common/cmd_net.c NetLoop() back without error 3112 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3113 82 common/cmd_net.c trying automatic boot 3114 83 common/cmd_net.c running "source" command 3115 -83 common/cmd_net.c some error in automatic boot or "source" command 3116 84 common/cmd_net.c end without errors 3117 3118FIT uImage format: 3119 3120 Arg Where When 3121 100 common/cmd_bootm.c Kernel FIT Image has correct format 3122 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3123 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3124 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3125 102 common/cmd_bootm.c Kernel unit name specified 3126 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3127 103 common/cmd_bootm.c Found configuration node 3128 104 common/cmd_bootm.c Got kernel subimage node offset 3129 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3130 105 common/cmd_bootm.c Kernel subimage hash verification OK 3131 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3132 106 common/cmd_bootm.c Architecture check OK 3133 -106 common/cmd_bootm.c Kernel subimage has wrong type 3134 107 common/cmd_bootm.c Kernel subimage type OK 3135 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3136 108 common/cmd_bootm.c Got kernel subimage data/size 3137 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3138 -109 common/cmd_bootm.c Can't get kernel subimage type 3139 -110 common/cmd_bootm.c Can't get kernel subimage comp 3140 -111 common/cmd_bootm.c Can't get kernel subimage os 3141 -112 common/cmd_bootm.c Can't get kernel subimage load address 3142 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3143 3144 120 common/image.c Start initial ramdisk verification 3145 -120 common/image.c Ramdisk FIT image has incorrect format 3146 121 common/image.c Ramdisk FIT image has correct format 3147 122 common/image.c No ramdisk subimage unit name, using configuration 3148 -122 common/image.c Can't get configuration for ramdisk subimage 3149 123 common/image.c Ramdisk unit name specified 3150 -124 common/image.c Can't get ramdisk subimage node offset 3151 125 common/image.c Got ramdisk subimage node offset 3152 -125 common/image.c Ramdisk subimage hash verification failed 3153 126 common/image.c Ramdisk subimage hash verification OK 3154 -126 common/image.c Ramdisk subimage for unsupported architecture 3155 127 common/image.c Architecture check OK 3156 -127 common/image.c Can't get ramdisk subimage data/size 3157 128 common/image.c Got ramdisk subimage data/size 3158 129 common/image.c Can't get ramdisk load address 3159 -129 common/image.c Got ramdisk load address 3160 3161 -130 common/cmd_doc.c Incorrect FIT image format 3162 131 common/cmd_doc.c FIT image format OK 3163 3164 -140 common/cmd_ide.c Incorrect FIT image format 3165 141 common/cmd_ide.c FIT image format OK 3166 3167 -150 common/cmd_nand.c Incorrect FIT image format 3168 151 common/cmd_nand.c FIT image format OK 3169 3170- FIT image support: 3171 CONFIG_FIT 3172 Enable support for the FIT uImage format. 3173 3174 CONFIG_FIT_BEST_MATCH 3175 When no configuration is explicitly selected, default to the 3176 one whose fdt's compatibility field best matches that of 3177 U-Boot itself. A match is considered "best" if it matches the 3178 most specific compatibility entry of U-Boot's fdt's root node. 3179 The order of entries in the configuration's fdt is ignored. 3180 3181 CONFIG_FIT_SIGNATURE 3182 This option enables signature verification of FIT uImages, 3183 using a hash signed and verified using RSA. See 3184 doc/uImage.FIT/signature.txt for more details. 3185 3186- Standalone program support: 3187 CONFIG_STANDALONE_LOAD_ADDR 3188 3189 This option defines a board specific value for the 3190 address where standalone program gets loaded, thus 3191 overwriting the architecture dependent default 3192 settings. 3193 3194- Frame Buffer Address: 3195 CONFIG_FB_ADDR 3196 3197 Define CONFIG_FB_ADDR if you want to use specific 3198 address for frame buffer. This is typically the case 3199 when using a graphics controller has separate video 3200 memory. U-Boot will then place the frame buffer at 3201 the given address instead of dynamically reserving it 3202 in system RAM by calling lcd_setmem(), which grabs 3203 the memory for the frame buffer depending on the 3204 configured panel size. 3205 3206 Please see board_init_f function. 3207 3208- Automatic software updates via TFTP server 3209 CONFIG_UPDATE_TFTP 3210 CONFIG_UPDATE_TFTP_CNT_MAX 3211 CONFIG_UPDATE_TFTP_MSEC_MAX 3212 3213 These options enable and control the auto-update feature; 3214 for a more detailed description refer to doc/README.update. 3215 3216- MTD Support (mtdparts command, UBI support) 3217 CONFIG_MTD_DEVICE 3218 3219 Adds the MTD device infrastructure from the Linux kernel. 3220 Needed for mtdparts command support. 3221 3222 CONFIG_MTD_PARTITIONS 3223 3224 Adds the MTD partitioning infrastructure from the Linux 3225 kernel. Needed for UBI support. 3226 3227- UBI support 3228 CONFIG_CMD_UBI 3229 3230 Adds commands for interacting with MTD partitions formatted 3231 with the UBI flash translation layer 3232 3233 Requires also defining CONFIG_RBTREE 3234 3235 CONFIG_UBI_SILENCE_MSG 3236 3237 Make the verbose messages from UBI stop printing. This leaves 3238 warnings and errors enabled. 3239 3240- UBIFS support 3241 CONFIG_CMD_UBIFS 3242 3243 Adds commands for interacting with UBI volumes formatted as 3244 UBIFS. UBIFS is read-only in u-boot. 3245 3246 Requires UBI support as well as CONFIG_LZO 3247 3248 CONFIG_UBIFS_SILENCE_MSG 3249 3250 Make the verbose messages from UBIFS stop printing. This leaves 3251 warnings and errors enabled. 3252 3253- SPL framework 3254 CONFIG_SPL 3255 Enable building of SPL globally. 3256 3257 CONFIG_SPL_LDSCRIPT 3258 LDSCRIPT for linking the SPL binary. 3259 3260 CONFIG_SPL_MAX_FOOTPRINT 3261 Maximum size in memory allocated to the SPL, BSS included. 3262 When defined, the linker checks that the actual memory 3263 used by SPL from _start to __bss_end does not exceed it. 3264 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3265 must not be both defined at the same time. 3266 3267 CONFIG_SPL_MAX_SIZE 3268 Maximum size of the SPL image (text, data, rodata, and 3269 linker lists sections), BSS excluded. 3270 When defined, the linker checks that the actual size does 3271 not exceed it. 3272 3273 CONFIG_SPL_TEXT_BASE 3274 TEXT_BASE for linking the SPL binary. 3275 3276 CONFIG_SPL_RELOC_TEXT_BASE 3277 Address to relocate to. If unspecified, this is equal to 3278 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3279 3280 CONFIG_SPL_BSS_START_ADDR 3281 Link address for the BSS within the SPL binary. 3282 3283 CONFIG_SPL_BSS_MAX_SIZE 3284 Maximum size in memory allocated to the SPL BSS. 3285 When defined, the linker checks that the actual memory used 3286 by SPL from __bss_start to __bss_end does not exceed it. 3287 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3288 must not be both defined at the same time. 3289 3290 CONFIG_SPL_STACK 3291 Adress of the start of the stack SPL will use 3292 3293 CONFIG_SPL_RELOC_STACK 3294 Adress of the start of the stack SPL will use after 3295 relocation. If unspecified, this is equal to 3296 CONFIG_SPL_STACK. 3297 3298 CONFIG_SYS_SPL_MALLOC_START 3299 Starting address of the malloc pool used in SPL. 3300 3301 CONFIG_SYS_SPL_MALLOC_SIZE 3302 The size of the malloc pool used in SPL. 3303 3304 CONFIG_SPL_FRAMEWORK 3305 Enable the SPL framework under common/. This framework 3306 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3307 NAND loading of the Linux Kernel. 3308 3309 CONFIG_SPL_OS_BOOT 3310 Enable booting directly to an OS from SPL. 3311 See also: doc/README.falcon 3312 3313 CONFIG_SPL_DISPLAY_PRINT 3314 For ARM, enable an optional function to print more information 3315 about the running system. 3316 3317 CONFIG_SPL_INIT_MINIMAL 3318 Arch init code should be built for a very small image 3319 3320 CONFIG_SPL_LIBCOMMON_SUPPORT 3321 Support for common/libcommon.o in SPL binary 3322 3323 CONFIG_SPL_LIBDISK_SUPPORT 3324 Support for disk/libdisk.o in SPL binary 3325 3326 CONFIG_SPL_I2C_SUPPORT 3327 Support for drivers/i2c/libi2c.o in SPL binary 3328 3329 CONFIG_SPL_GPIO_SUPPORT 3330 Support for drivers/gpio/libgpio.o in SPL binary 3331 3332 CONFIG_SPL_MMC_SUPPORT 3333 Support for drivers/mmc/libmmc.o in SPL binary 3334 3335 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3336 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3337 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION 3338 Address, size and partition on the MMC to load U-Boot from 3339 when the MMC is being used in raw mode. 3340 3341 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3342 Sector to load kernel uImage from when MMC is being 3343 used in raw mode (for Falcon mode) 3344 3345 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3346 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3347 Sector and number of sectors to load kernel argument 3348 parameters from when MMC is being used in raw mode 3349 (for falcon mode) 3350 3351 CONFIG_SPL_FAT_SUPPORT 3352 Support for fs/fat/libfat.o in SPL binary 3353 3354 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME 3355 Filename to read to load U-Boot when reading from FAT 3356 3357 CONFIG_SPL_FAT_LOAD_KERNEL_NAME 3358 Filename to read to load kernel uImage when reading 3359 from FAT (for Falcon mode) 3360 3361 CONFIG_SPL_FAT_LOAD_ARGS_NAME 3362 Filename to read to load kernel argument parameters 3363 when reading from FAT (for Falcon mode) 3364 3365 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3366 Set this for NAND SPL on PPC mpc83xx targets, so that 3367 start.S waits for the rest of the SPL to load before 3368 continuing (the hardware starts execution after just 3369 loading the first page rather than the full 4K). 3370 3371 CONFIG_SPL_SKIP_RELOCATE 3372 Avoid SPL relocation 3373 3374 CONFIG_SPL_NAND_BASE 3375 Include nand_base.c in the SPL. Requires 3376 CONFIG_SPL_NAND_DRIVERS. 3377 3378 CONFIG_SPL_NAND_DRIVERS 3379 SPL uses normal NAND drivers, not minimal drivers. 3380 3381 CONFIG_SPL_NAND_ECC 3382 Include standard software ECC in the SPL 3383 3384 CONFIG_SPL_NAND_SIMPLE 3385 Support for NAND boot using simple NAND drivers that 3386 expose the cmd_ctrl() interface. 3387 3388 CONFIG_SPL_MTD_SUPPORT 3389 Support for the MTD subsystem within SPL. Useful for 3390 environment on NAND support within SPL. 3391 3392 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3393 Set for the SPL on PPC mpc8xxx targets, support for 3394 drivers/ddr/fsl/libddr.o in SPL binary. 3395 3396 CONFIG_SPL_COMMON_INIT_DDR 3397 Set for common ddr init with serial presence detect in 3398 SPL binary. 3399 3400 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3401 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3402 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3403 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3404 CONFIG_SYS_NAND_ECCBYTES 3405 Defines the size and behavior of the NAND that SPL uses 3406 to read U-Boot 3407 3408 CONFIG_SPL_NAND_BOOT 3409 Add support NAND boot 3410 3411 CONFIG_SYS_NAND_U_BOOT_OFFS 3412 Location in NAND to read U-Boot from 3413 3414 CONFIG_SYS_NAND_U_BOOT_DST 3415 Location in memory to load U-Boot to 3416 3417 CONFIG_SYS_NAND_U_BOOT_SIZE 3418 Size of image to load 3419 3420 CONFIG_SYS_NAND_U_BOOT_START 3421 Entry point in loaded image to jump to 3422 3423 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3424 Define this if you need to first read the OOB and then the 3425 data. This is used for example on davinci plattforms. 3426 3427 CONFIG_SPL_OMAP3_ID_NAND 3428 Support for an OMAP3-specific set of functions to return the 3429 ID and MFR of the first attached NAND chip, if present. 3430 3431 CONFIG_SPL_SERIAL_SUPPORT 3432 Support for drivers/serial/libserial.o in SPL binary 3433 3434 CONFIG_SPL_SPI_FLASH_SUPPORT 3435 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3436 3437 CONFIG_SPL_SPI_SUPPORT 3438 Support for drivers/spi/libspi.o in SPL binary 3439 3440 CONFIG_SPL_RAM_DEVICE 3441 Support for running image already present in ram, in SPL binary 3442 3443 CONFIG_SPL_LIBGENERIC_SUPPORT 3444 Support for lib/libgeneric.o in SPL binary 3445 3446 CONFIG_SPL_ENV_SUPPORT 3447 Support for the environment operating in SPL binary 3448 3449 CONFIG_SPL_NET_SUPPORT 3450 Support for the net/libnet.o in SPL binary. 3451 It conflicts with SPL env from storage medium specified by 3452 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3453 3454 CONFIG_SPL_PAD_TO 3455 Image offset to which the SPL should be padded before appending 3456 the SPL payload. By default, this is defined as 3457 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3458 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3459 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3460 3461 CONFIG_SPL_TARGET 3462 Final target image containing SPL and payload. Some SPLs 3463 use an arch-specific makefile fragment instead, for 3464 example if more than one image needs to be produced. 3465 3466 CONFIG_FIT_SPL_PRINT 3467 Printing information about a FIT image adds quite a bit of 3468 code to SPL. So this is normally disabled in SPL. Use this 3469 option to re-enable it. This will affect the output of the 3470 bootm command when booting a FIT image. 3471 3472- TPL framework 3473 CONFIG_TPL 3474 Enable building of TPL globally. 3475 3476 CONFIG_TPL_PAD_TO 3477 Image offset to which the TPL should be padded before appending 3478 the TPL payload. By default, this is defined as 3479 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3480 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3481 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3482 3483Modem Support: 3484-------------- 3485 3486[so far only for SMDK2400 boards] 3487 3488- Modem support enable: 3489 CONFIG_MODEM_SUPPORT 3490 3491- RTS/CTS Flow control enable: 3492 CONFIG_HWFLOW 3493 3494- Modem debug support: 3495 CONFIG_MODEM_SUPPORT_DEBUG 3496 3497 Enables debugging stuff (char screen[1024], dbg()) 3498 for modem support. Useful only with BDI2000. 3499 3500- Interrupt support (PPC): 3501 3502 There are common interrupt_init() and timer_interrupt() 3503 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3504 for CPU specific initialization. interrupt_init_cpu() 3505 should set decrementer_count to appropriate value. If 3506 CPU resets decrementer automatically after interrupt 3507 (ppc4xx) it should set decrementer_count to zero. 3508 timer_interrupt() calls timer_interrupt_cpu() for CPU 3509 specific handling. If board has watchdog / status_led 3510 / other_activity_monitor it works automatically from 3511 general timer_interrupt(). 3512 3513- General: 3514 3515 In the target system modem support is enabled when a 3516 specific key (key combination) is pressed during 3517 power-on. Otherwise U-Boot will boot normally 3518 (autoboot). The key_pressed() function is called from 3519 board_init(). Currently key_pressed() is a dummy 3520 function, returning 1 and thus enabling modem 3521 initialization. 3522 3523 If there are no modem init strings in the 3524 environment, U-Boot proceed to autoboot; the 3525 previous output (banner, info printfs) will be 3526 suppressed, though. 3527 3528 See also: doc/README.Modem 3529 3530Board initialization settings: 3531------------------------------ 3532 3533During Initialization u-boot calls a number of board specific functions 3534to allow the preparation of board specific prerequisites, e.g. pin setup 3535before drivers are initialized. To enable these callbacks the 3536following configuration macros have to be defined. Currently this is 3537architecture specific, so please check arch/your_architecture/lib/board.c 3538typically in board_init_f() and board_init_r(). 3539 3540- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3541- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3542- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3543- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3544 3545Configuration Settings: 3546----------------------- 3547 3548- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3549 Optionally it can be defined to support 64-bit memory commands. 3550 3551- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3552 undefine this when you're short of memory. 3553 3554- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3555 width of the commands listed in the 'help' command output. 3556 3557- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3558 prompt for user input. 3559 3560- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3561 3562- CONFIG_SYS_PBSIZE: Buffer size for Console output 3563 3564- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3565 3566- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3567 the application (usually a Linux kernel) when it is 3568 booted 3569 3570- CONFIG_SYS_BAUDRATE_TABLE: 3571 List of legal baudrate settings for this board. 3572 3573- CONFIG_SYS_CONSOLE_INFO_QUIET 3574 Suppress display of console information at boot. 3575 3576- CONFIG_SYS_CONSOLE_IS_IN_ENV 3577 If the board specific function 3578 extern int overwrite_console (void); 3579 returns 1, the stdin, stderr and stdout are switched to the 3580 serial port, else the settings in the environment are used. 3581 3582- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3583 Enable the call to overwrite_console(). 3584 3585- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3586 Enable overwrite of previous console environment settings. 3587 3588- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3589 Begin and End addresses of the area used by the 3590 simple memory test. 3591 3592- CONFIG_SYS_ALT_MEMTEST: 3593 Enable an alternate, more extensive memory test. 3594 3595- CONFIG_SYS_MEMTEST_SCRATCH: 3596 Scratch address used by the alternate memory test 3597 You only need to set this if address zero isn't writeable 3598 3599- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3600 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3601 this specified memory area will get subtracted from the top 3602 (end) of RAM and won't get "touched" at all by U-Boot. By 3603 fixing up gd->ram_size the Linux kernel should gets passed 3604 the now "corrected" memory size and won't touch it either. 3605 This should work for arch/ppc and arch/powerpc. Only Linux 3606 board ports in arch/powerpc with bootwrapper support that 3607 recalculate the memory size from the SDRAM controller setup 3608 will have to get fixed in Linux additionally. 3609 3610 This option can be used as a workaround for the 440EPx/GRx 3611 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3612 be touched. 3613 3614 WARNING: Please make sure that this value is a multiple of 3615 the Linux page size (normally 4k). If this is not the case, 3616 then the end address of the Linux memory will be located at a 3617 non page size aligned address and this could cause major 3618 problems. 3619 3620- CONFIG_SYS_LOADS_BAUD_CHANGE: 3621 Enable temporary baudrate change while serial download 3622 3623- CONFIG_SYS_SDRAM_BASE: 3624 Physical start address of SDRAM. _Must_ be 0 here. 3625 3626- CONFIG_SYS_MBIO_BASE: 3627 Physical start address of Motherboard I/O (if using a 3628 Cogent motherboard) 3629 3630- CONFIG_SYS_FLASH_BASE: 3631 Physical start address of Flash memory. 3632 3633- CONFIG_SYS_MONITOR_BASE: 3634 Physical start address of boot monitor code (set by 3635 make config files to be same as the text base address 3636 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3637 CONFIG_SYS_FLASH_BASE when booting from flash. 3638 3639- CONFIG_SYS_MONITOR_LEN: 3640 Size of memory reserved for monitor code, used to 3641 determine _at_compile_time_ (!) if the environment is 3642 embedded within the U-Boot image, or in a separate 3643 flash sector. 3644 3645- CONFIG_SYS_MALLOC_LEN: 3646 Size of DRAM reserved for malloc() use. 3647 3648- CONFIG_SYS_BOOTM_LEN: 3649 Normally compressed uImages are limited to an 3650 uncompressed size of 8 MBytes. If this is not enough, 3651 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3652 to adjust this setting to your needs. 3653 3654- CONFIG_SYS_BOOTMAPSZ: 3655 Maximum size of memory mapped by the startup code of 3656 the Linux kernel; all data that must be processed by 3657 the Linux kernel (bd_info, boot arguments, FDT blob if 3658 used) must be put below this limit, unless "bootm_low" 3659 environment variable is defined and non-zero. In such case 3660 all data for the Linux kernel must be between "bootm_low" 3661 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3662 variable "bootm_mapsize" will override the value of 3663 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3664 then the value in "bootm_size" will be used instead. 3665 3666- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3667 Enable initrd_high functionality. If defined then the 3668 initrd_high feature is enabled and the bootm ramdisk subcommand 3669 is enabled. 3670 3671- CONFIG_SYS_BOOT_GET_CMDLINE: 3672 Enables allocating and saving kernel cmdline in space between 3673 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3674 3675- CONFIG_SYS_BOOT_GET_KBD: 3676 Enables allocating and saving a kernel copy of the bd_info in 3677 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3678 3679- CONFIG_SYS_MAX_FLASH_BANKS: 3680 Max number of Flash memory banks 3681 3682- CONFIG_SYS_MAX_FLASH_SECT: 3683 Max number of sectors on a Flash chip 3684 3685- CONFIG_SYS_FLASH_ERASE_TOUT: 3686 Timeout for Flash erase operations (in ms) 3687 3688- CONFIG_SYS_FLASH_WRITE_TOUT: 3689 Timeout for Flash write operations (in ms) 3690 3691- CONFIG_SYS_FLASH_LOCK_TOUT 3692 Timeout for Flash set sector lock bit operation (in ms) 3693 3694- CONFIG_SYS_FLASH_UNLOCK_TOUT 3695 Timeout for Flash clear lock bits operation (in ms) 3696 3697- CONFIG_SYS_FLASH_PROTECTION 3698 If defined, hardware flash sectors protection is used 3699 instead of U-Boot software protection. 3700 3701- CONFIG_SYS_DIRECT_FLASH_TFTP: 3702 3703 Enable TFTP transfers directly to flash memory; 3704 without this option such a download has to be 3705 performed in two steps: (1) download to RAM, and (2) 3706 copy from RAM to flash. 3707 3708 The two-step approach is usually more reliable, since 3709 you can check if the download worked before you erase 3710 the flash, but in some situations (when system RAM is 3711 too limited to allow for a temporary copy of the 3712 downloaded image) this option may be very useful. 3713 3714- CONFIG_SYS_FLASH_CFI: 3715 Define if the flash driver uses extra elements in the 3716 common flash structure for storing flash geometry. 3717 3718- CONFIG_FLASH_CFI_DRIVER 3719 This option also enables the building of the cfi_flash driver 3720 in the drivers directory 3721 3722- CONFIG_FLASH_CFI_MTD 3723 This option enables the building of the cfi_mtd driver 3724 in the drivers directory. The driver exports CFI flash 3725 to the MTD layer. 3726 3727- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3728 Use buffered writes to flash. 3729 3730- CONFIG_FLASH_SPANSION_S29WS_N 3731 s29ws-n MirrorBit flash has non-standard addresses for buffered 3732 write commands. 3733 3734- CONFIG_SYS_FLASH_QUIET_TEST 3735 If this option is defined, the common CFI flash doesn't 3736 print it's warning upon not recognized FLASH banks. This 3737 is useful, if some of the configured banks are only 3738 optionally available. 3739 3740- CONFIG_FLASH_SHOW_PROGRESS 3741 If defined (must be an integer), print out countdown 3742 digits and dots. Recommended value: 45 (9..1) for 80 3743 column displays, 15 (3..1) for 40 column displays. 3744 3745- CONFIG_FLASH_VERIFY 3746 If defined, the content of the flash (destination) is compared 3747 against the source after the write operation. An error message 3748 will be printed when the contents are not identical. 3749 Please note that this option is useless in nearly all cases, 3750 since such flash programming errors usually are detected earlier 3751 while unprotecting/erasing/programming. Please only enable 3752 this option if you really know what you are doing. 3753 3754- CONFIG_SYS_RX_ETH_BUFFER: 3755 Defines the number of Ethernet receive buffers. On some 3756 Ethernet controllers it is recommended to set this value 3757 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3758 buffers can be full shortly after enabling the interface 3759 on high Ethernet traffic. 3760 Defaults to 4 if not defined. 3761 3762- CONFIG_ENV_MAX_ENTRIES 3763 3764 Maximum number of entries in the hash table that is used 3765 internally to store the environment settings. The default 3766 setting is supposed to be generous and should work in most 3767 cases. This setting can be used to tune behaviour; see 3768 lib/hashtable.c for details. 3769 3770- CONFIG_ENV_FLAGS_LIST_DEFAULT 3771- CONFIG_ENV_FLAGS_LIST_STATIC 3772 Enable validation of the values given to environment variables when 3773 calling env set. Variables can be restricted to only decimal, 3774 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3775 the variables can also be restricted to IP address or MAC address. 3776 3777 The format of the list is: 3778 type_attribute = [s|d|x|b|i|m] 3779 access_atribute = [a|r|o|c] 3780 attributes = type_attribute[access_atribute] 3781 entry = variable_name[:attributes] 3782 list = entry[,list] 3783 3784 The type attributes are: 3785 s - String (default) 3786 d - Decimal 3787 x - Hexadecimal 3788 b - Boolean ([1yYtT|0nNfF]) 3789 i - IP address 3790 m - MAC address 3791 3792 The access attributes are: 3793 a - Any (default) 3794 r - Read-only 3795 o - Write-once 3796 c - Change-default 3797 3798 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3799 Define this to a list (string) to define the ".flags" 3800 envirnoment variable in the default or embedded environment. 3801 3802 - CONFIG_ENV_FLAGS_LIST_STATIC 3803 Define this to a list (string) to define validation that 3804 should be done if an entry is not found in the ".flags" 3805 environment variable. To override a setting in the static 3806 list, simply add an entry for the same variable name to the 3807 ".flags" variable. 3808 3809- CONFIG_ENV_ACCESS_IGNORE_FORCE 3810 If defined, don't allow the -f switch to env set override variable 3811 access flags. 3812 3813- CONFIG_SYS_GENERIC_BOARD 3814 This selects the architecture-generic board system instead of the 3815 architecture-specific board files. It is intended to move boards 3816 to this new framework over time. Defining this will disable the 3817 arch/foo/lib/board.c file and use common/board_f.c and 3818 common/board_r.c instead. To use this option your architecture 3819 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in 3820 its config.mk file). If you find problems enabling this option on 3821 your board please report the problem and send patches! 3822 3823- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 3824 This is set by OMAP boards for the max time that reset should 3825 be asserted. See doc/README.omap-reset-time for details on how 3826 the value can be calulated on a given board. 3827 3828The following definitions that deal with the placement and management 3829of environment data (variable area); in general, we support the 3830following configurations: 3831 3832- CONFIG_BUILD_ENVCRC: 3833 3834 Builds up envcrc with the target environment so that external utils 3835 may easily extract it and embed it in final U-Boot images. 3836 3837- CONFIG_ENV_IS_IN_FLASH: 3838 3839 Define this if the environment is in flash memory. 3840 3841 a) The environment occupies one whole flash sector, which is 3842 "embedded" in the text segment with the U-Boot code. This 3843 happens usually with "bottom boot sector" or "top boot 3844 sector" type flash chips, which have several smaller 3845 sectors at the start or the end. For instance, such a 3846 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3847 such a case you would place the environment in one of the 3848 4 kB sectors - with U-Boot code before and after it. With 3849 "top boot sector" type flash chips, you would put the 3850 environment in one of the last sectors, leaving a gap 3851 between U-Boot and the environment. 3852 3853 - CONFIG_ENV_OFFSET: 3854 3855 Offset of environment data (variable area) to the 3856 beginning of flash memory; for instance, with bottom boot 3857 type flash chips the second sector can be used: the offset 3858 for this sector is given here. 3859 3860 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3861 3862 - CONFIG_ENV_ADDR: 3863 3864 This is just another way to specify the start address of 3865 the flash sector containing the environment (instead of 3866 CONFIG_ENV_OFFSET). 3867 3868 - CONFIG_ENV_SECT_SIZE: 3869 3870 Size of the sector containing the environment. 3871 3872 3873 b) Sometimes flash chips have few, equal sized, BIG sectors. 3874 In such a case you don't want to spend a whole sector for 3875 the environment. 3876 3877 - CONFIG_ENV_SIZE: 3878 3879 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3880 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3881 of this flash sector for the environment. This saves 3882 memory for the RAM copy of the environment. 3883 3884 It may also save flash memory if you decide to use this 3885 when your environment is "embedded" within U-Boot code, 3886 since then the remainder of the flash sector could be used 3887 for U-Boot code. It should be pointed out that this is 3888 STRONGLY DISCOURAGED from a robustness point of view: 3889 updating the environment in flash makes it always 3890 necessary to erase the WHOLE sector. If something goes 3891 wrong before the contents has been restored from a copy in 3892 RAM, your target system will be dead. 3893 3894 - CONFIG_ENV_ADDR_REDUND 3895 CONFIG_ENV_SIZE_REDUND 3896 3897 These settings describe a second storage area used to hold 3898 a redundant copy of the environment data, so that there is 3899 a valid backup copy in case there is a power failure during 3900 a "saveenv" operation. 3901 3902BE CAREFUL! Any changes to the flash layout, and some changes to the 3903source code will make it necessary to adapt <board>/u-boot.lds* 3904accordingly! 3905 3906 3907- CONFIG_ENV_IS_IN_NVRAM: 3908 3909 Define this if you have some non-volatile memory device 3910 (NVRAM, battery buffered SRAM) which you want to use for the 3911 environment. 3912 3913 - CONFIG_ENV_ADDR: 3914 - CONFIG_ENV_SIZE: 3915 3916 These two #defines are used to determine the memory area you 3917 want to use for environment. It is assumed that this memory 3918 can just be read and written to, without any special 3919 provision. 3920 3921BE CAREFUL! The first access to the environment happens quite early 3922in U-Boot initalization (when we try to get the setting of for the 3923console baudrate). You *MUST* have mapped your NVRAM area then, or 3924U-Boot will hang. 3925 3926Please note that even with NVRAM we still use a copy of the 3927environment in RAM: we could work on NVRAM directly, but we want to 3928keep settings there always unmodified except somebody uses "saveenv" 3929to save the current settings. 3930 3931 3932- CONFIG_ENV_IS_IN_EEPROM: 3933 3934 Use this if you have an EEPROM or similar serial access 3935 device and a driver for it. 3936 3937 - CONFIG_ENV_OFFSET: 3938 - CONFIG_ENV_SIZE: 3939 3940 These two #defines specify the offset and size of the 3941 environment area within the total memory of your EEPROM. 3942 3943 - CONFIG_SYS_I2C_EEPROM_ADDR: 3944 If defined, specified the chip address of the EEPROM device. 3945 The default address is zero. 3946 3947 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3948 If defined, the number of bits used to address bytes in a 3949 single page in the EEPROM device. A 64 byte page, for example 3950 would require six bits. 3951 3952 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3953 If defined, the number of milliseconds to delay between 3954 page writes. The default is zero milliseconds. 3955 3956 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3957 The length in bytes of the EEPROM memory array address. Note 3958 that this is NOT the chip address length! 3959 3960 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3961 EEPROM chips that implement "address overflow" are ones 3962 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3963 address and the extra bits end up in the "chip address" bit 3964 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3965 byte chips. 3966 3967 Note that we consider the length of the address field to 3968 still be one byte because the extra address bits are hidden 3969 in the chip address. 3970 3971 - CONFIG_SYS_EEPROM_SIZE: 3972 The size in bytes of the EEPROM device. 3973 3974 - CONFIG_ENV_EEPROM_IS_ON_I2C 3975 define this, if you have I2C and SPI activated, and your 3976 EEPROM, which holds the environment, is on the I2C bus. 3977 3978 - CONFIG_I2C_ENV_EEPROM_BUS 3979 if you have an Environment on an EEPROM reached over 3980 I2C muxes, you can define here, how to reach this 3981 EEPROM. For example: 3982 3983 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3984 3985 EEPROM which holds the environment, is reached over 3986 a pca9547 i2c mux with address 0x70, channel 3. 3987 3988- CONFIG_ENV_IS_IN_DATAFLASH: 3989 3990 Define this if you have a DataFlash memory device which you 3991 want to use for the environment. 3992 3993 - CONFIG_ENV_OFFSET: 3994 - CONFIG_ENV_ADDR: 3995 - CONFIG_ENV_SIZE: 3996 3997 These three #defines specify the offset and size of the 3998 environment area within the total memory of your DataFlash placed 3999 at the specified address. 4000 4001- CONFIG_ENV_IS_IN_REMOTE: 4002 4003 Define this if you have a remote memory space which you 4004 want to use for the local device's environment. 4005 4006 - CONFIG_ENV_ADDR: 4007 - CONFIG_ENV_SIZE: 4008 4009 These two #defines specify the address and size of the 4010 environment area within the remote memory space. The 4011 local device can get the environment from remote memory 4012 space by SRIO or PCIE links. 4013 4014BE CAREFUL! For some special cases, the local device can not use 4015"saveenv" command. For example, the local device will get the 4016environment stored in a remote NOR flash by SRIO or PCIE link, 4017but it can not erase, write this NOR flash by SRIO or PCIE interface. 4018 4019- CONFIG_ENV_IS_IN_NAND: 4020 4021 Define this if you have a NAND device which you want to use 4022 for the environment. 4023 4024 - CONFIG_ENV_OFFSET: 4025 - CONFIG_ENV_SIZE: 4026 4027 These two #defines specify the offset and size of the environment 4028 area within the first NAND device. CONFIG_ENV_OFFSET must be 4029 aligned to an erase block boundary. 4030 4031 - CONFIG_ENV_OFFSET_REDUND (optional): 4032 4033 This setting describes a second storage area of CONFIG_ENV_SIZE 4034 size used to hold a redundant copy of the environment data, so 4035 that there is a valid backup copy in case there is a power failure 4036 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4037 aligned to an erase block boundary. 4038 4039 - CONFIG_ENV_RANGE (optional): 4040 4041 Specifies the length of the region in which the environment 4042 can be written. This should be a multiple of the NAND device's 4043 block size. Specifying a range with more erase blocks than 4044 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4045 the range to be avoided. 4046 4047 - CONFIG_ENV_OFFSET_OOB (optional): 4048 4049 Enables support for dynamically retrieving the offset of the 4050 environment from block zero's out-of-band data. The 4051 "nand env.oob" command can be used to record this offset. 4052 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4053 using CONFIG_ENV_OFFSET_OOB. 4054 4055- CONFIG_NAND_ENV_DST 4056 4057 Defines address in RAM to which the nand_spl code should copy the 4058 environment. If redundant environment is used, it will be copied to 4059 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4060 4061- CONFIG_ENV_IS_IN_UBI: 4062 4063 Define this if you have an UBI volume that you want to use for the 4064 environment. This has the benefit of wear-leveling the environment 4065 accesses, which is important on NAND. 4066 4067 - CONFIG_ENV_UBI_PART: 4068 4069 Define this to a string that is the mtd partition containing the UBI. 4070 4071 - CONFIG_ENV_UBI_VOLUME: 4072 4073 Define this to the name of the volume that you want to store the 4074 environment in. 4075 4076 - CONFIG_ENV_UBI_VOLUME_REDUND: 4077 4078 Define this to the name of another volume to store a second copy of 4079 the environment in. This will enable redundant environments in UBI. 4080 It is assumed that both volumes are in the same MTD partition. 4081 4082 - CONFIG_UBI_SILENCE_MSG 4083 - CONFIG_UBIFS_SILENCE_MSG 4084 4085 You will probably want to define these to avoid a really noisy system 4086 when storing the env in UBI. 4087 4088- CONFIG_ENV_IS_IN_MMC: 4089 4090 Define this if you have an MMC device which you want to use for the 4091 environment. 4092 4093 - CONFIG_SYS_MMC_ENV_DEV: 4094 4095 Specifies which MMC device the environment is stored in. 4096 4097 - CONFIG_SYS_MMC_ENV_PART (optional): 4098 4099 Specifies which MMC partition the environment is stored in. If not 4100 set, defaults to partition 0, the user area. Common values might be 4101 1 (first MMC boot partition), 2 (second MMC boot partition). 4102 4103 - CONFIG_ENV_OFFSET: 4104 - CONFIG_ENV_SIZE: 4105 4106 These two #defines specify the offset and size of the environment 4107 area within the specified MMC device. 4108 4109 If offset is positive (the usual case), it is treated as relative to 4110 the start of the MMC partition. If offset is negative, it is treated 4111 as relative to the end of the MMC partition. This can be useful if 4112 your board may be fitted with different MMC devices, which have 4113 different sizes for the MMC partitions, and you always want the 4114 environment placed at the very end of the partition, to leave the 4115 maximum possible space before it, to store other data. 4116 4117 These two values are in units of bytes, but must be aligned to an 4118 MMC sector boundary. 4119 4120 - CONFIG_ENV_OFFSET_REDUND (optional): 4121 4122 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4123 hold a redundant copy of the environment data. This provides a 4124 valid backup copy in case the other copy is corrupted, e.g. due 4125 to a power failure during a "saveenv" operation. 4126 4127 This value may also be positive or negative; this is handled in the 4128 same way as CONFIG_ENV_OFFSET. 4129 4130 This value is also in units of bytes, but must also be aligned to 4131 an MMC sector boundary. 4132 4133 - CONFIG_ENV_SIZE_REDUND (optional): 4134 4135 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4136 set. If this value is set, it must be set to the same value as 4137 CONFIG_ENV_SIZE. 4138 4139- CONFIG_SYS_SPI_INIT_OFFSET 4140 4141 Defines offset to the initial SPI buffer area in DPRAM. The 4142 area is used at an early stage (ROM part) if the environment 4143 is configured to reside in the SPI EEPROM: We need a 520 byte 4144 scratch DPRAM area. It is used between the two initialization 4145 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4146 to be a good choice since it makes it far enough from the 4147 start of the data area as well as from the stack pointer. 4148 4149Please note that the environment is read-only until the monitor 4150has been relocated to RAM and a RAM copy of the environment has been 4151created; also, when using EEPROM you will have to use getenv_f() 4152until then to read environment variables. 4153 4154The environment is protected by a CRC32 checksum. Before the monitor 4155is relocated into RAM, as a result of a bad CRC you will be working 4156with the compiled-in default environment - *silently*!!! [This is 4157necessary, because the first environment variable we need is the 4158"baudrate" setting for the console - if we have a bad CRC, we don't 4159have any device yet where we could complain.] 4160 4161Note: once the monitor has been relocated, then it will complain if 4162the default environment is used; a new CRC is computed as soon as you 4163use the "saveenv" command to store a valid environment. 4164 4165- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4166 Echo the inverted Ethernet link state to the fault LED. 4167 4168 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4169 also needs to be defined. 4170 4171- CONFIG_SYS_FAULT_MII_ADDR: 4172 MII address of the PHY to check for the Ethernet link state. 4173 4174- CONFIG_NS16550_MIN_FUNCTIONS: 4175 Define this if you desire to only have use of the NS16550_init 4176 and NS16550_putc functions for the serial driver located at 4177 drivers/serial/ns16550.c. This option is useful for saving 4178 space for already greatly restricted images, including but not 4179 limited to NAND_SPL configurations. 4180 4181- CONFIG_DISPLAY_BOARDINFO 4182 Display information about the board that U-Boot is running on 4183 when U-Boot starts up. The board function checkboard() is called 4184 to do this. 4185 4186- CONFIG_DISPLAY_BOARDINFO_LATE 4187 Similar to the previous option, but display this information 4188 later, once stdio is running and output goes to the LCD, if 4189 present. 4190 4191Low Level (hardware related) configuration options: 4192--------------------------------------------------- 4193 4194- CONFIG_SYS_CACHELINE_SIZE: 4195 Cache Line Size of the CPU. 4196 4197- CONFIG_SYS_DEFAULT_IMMR: 4198 Default address of the IMMR after system reset. 4199 4200 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4201 and RPXsuper) to be able to adjust the position of 4202 the IMMR register after a reset. 4203 4204- CONFIG_SYS_CCSRBAR_DEFAULT: 4205 Default (power-on reset) physical address of CCSR on Freescale 4206 PowerPC SOCs. 4207 4208- CONFIG_SYS_CCSRBAR: 4209 Virtual address of CCSR. On a 32-bit build, this is typically 4210 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4211 4212 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4213 for cross-platform code that uses that macro instead. 4214 4215- CONFIG_SYS_CCSRBAR_PHYS: 4216 Physical address of CCSR. CCSR can be relocated to a new 4217 physical address, if desired. In this case, this macro should 4218 be set to that address. Otherwise, it should be set to the 4219 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4220 is typically relocated on 36-bit builds. It is recommended 4221 that this macro be defined via the _HIGH and _LOW macros: 4222 4223 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4224 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4225 4226- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4227 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4228 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4229 used in assembly code, so it must not contain typecasts or 4230 integer size suffixes (e.g. "ULL"). 4231 4232- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4233 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4234 used in assembly code, so it must not contain typecasts or 4235 integer size suffixes (e.g. "ULL"). 4236 4237- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4238 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4239 forced to a value that ensures that CCSR is not relocated. 4240 4241- Floppy Disk Support: 4242 CONFIG_SYS_FDC_DRIVE_NUMBER 4243 4244 the default drive number (default value 0) 4245 4246 CONFIG_SYS_ISA_IO_STRIDE 4247 4248 defines the spacing between FDC chipset registers 4249 (default value 1) 4250 4251 CONFIG_SYS_ISA_IO_OFFSET 4252 4253 defines the offset of register from address. It 4254 depends on which part of the data bus is connected to 4255 the FDC chipset. (default value 0) 4256 4257 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4258 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4259 default value. 4260 4261 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4262 fdc_hw_init() is called at the beginning of the FDC 4263 setup. fdc_hw_init() must be provided by the board 4264 source code. It is used to make hardware dependant 4265 initializations. 4266 4267- CONFIG_IDE_AHB: 4268 Most IDE controllers were designed to be connected with PCI 4269 interface. Only few of them were designed for AHB interface. 4270 When software is doing ATA command and data transfer to 4271 IDE devices through IDE-AHB controller, some additional 4272 registers accessing to these kind of IDE-AHB controller 4273 is requierd. 4274 4275- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4276 DO NOT CHANGE unless you know exactly what you're 4277 doing! (11-4) [MPC8xx/82xx systems only] 4278 4279- CONFIG_SYS_INIT_RAM_ADDR: 4280 4281 Start address of memory area that can be used for 4282 initial data and stack; please note that this must be 4283 writable memory that is working WITHOUT special 4284 initialization, i. e. you CANNOT use normal RAM which 4285 will become available only after programming the 4286 memory controller and running certain initialization 4287 sequences. 4288 4289 U-Boot uses the following memory types: 4290 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4291 - MPC824X: data cache 4292 - PPC4xx: data cache 4293 4294- CONFIG_SYS_GBL_DATA_OFFSET: 4295 4296 Offset of the initial data structure in the memory 4297 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4298 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4299 data is located at the end of the available space 4300 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4301 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4302 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4303 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4304 4305 Note: 4306 On the MPC824X (or other systems that use the data 4307 cache for initial memory) the address chosen for 4308 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4309 point to an otherwise UNUSED address space between 4310 the top of RAM and the start of the PCI space. 4311 4312- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4313 4314- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4315 4316- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4317 4318- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4319 4320- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4321 4322- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4323 4324- CONFIG_SYS_OR_TIMING_SDRAM: 4325 SDRAM timing 4326 4327- CONFIG_SYS_MAMR_PTA: 4328 periodic timer for refresh 4329 4330- CONFIG_SYS_DER: Debug Event Register (37-47) 4331 4332- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4333 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4334 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4335 CONFIG_SYS_BR1_PRELIM: 4336 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4337 4338- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4339 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4340 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4341 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4342 4343- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4344 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4345 Machine Mode Register and Memory Periodic Timer 4346 Prescaler definitions (SDRAM timing) 4347 4348- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4349 enable I2C microcode relocation patch (MPC8xx); 4350 define relocation offset in DPRAM [DSP2] 4351 4352- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4353 enable SMC microcode relocation patch (MPC8xx); 4354 define relocation offset in DPRAM [SMC1] 4355 4356- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4357 enable SPI microcode relocation patch (MPC8xx); 4358 define relocation offset in DPRAM [SCC4] 4359 4360- CONFIG_SYS_USE_OSCCLK: 4361 Use OSCM clock mode on MBX8xx board. Be careful, 4362 wrong setting might damage your board. Read 4363 doc/README.MBX before setting this variable! 4364 4365- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4366 Offset of the bootmode word in DPRAM used by post 4367 (Power On Self Tests). This definition overrides 4368 #define'd default value in commproc.h resp. 4369 cpm_8260.h. 4370 4371- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4372 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4373 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4374 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4375 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4376 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4377 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4378 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4379 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4380 4381- CONFIG_PCI_DISABLE_PCIE: 4382 Disable PCI-Express on systems where it is supported but not 4383 required. 4384 4385- CONFIG_PCI_ENUM_ONLY 4386 Only scan through and get the devices on the busses. 4387 Don't do any setup work, presumably because someone or 4388 something has already done it, and we don't need to do it 4389 a second time. Useful for platforms that are pre-booted 4390 by coreboot or similar. 4391 4392- CONFIG_PCI_INDIRECT_BRIDGE: 4393 Enable support for indirect PCI bridges. 4394 4395- CONFIG_SYS_SRIO: 4396 Chip has SRIO or not 4397 4398- CONFIG_SRIO1: 4399 Board has SRIO 1 port available 4400 4401- CONFIG_SRIO2: 4402 Board has SRIO 2 port available 4403 4404- CONFIG_SRIO_PCIE_BOOT_MASTER 4405 Board can support master function for Boot from SRIO and PCIE 4406 4407- CONFIG_SYS_SRIOn_MEM_VIRT: 4408 Virtual Address of SRIO port 'n' memory region 4409 4410- CONFIG_SYS_SRIOn_MEM_PHYS: 4411 Physical Address of SRIO port 'n' memory region 4412 4413- CONFIG_SYS_SRIOn_MEM_SIZE: 4414 Size of SRIO port 'n' memory region 4415 4416- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4417 Defined to tell the NAND controller that the NAND chip is using 4418 a 16 bit bus. 4419 Not all NAND drivers use this symbol. 4420 Example of drivers that use it: 4421 - drivers/mtd/nand/ndfc.c 4422 - drivers/mtd/nand/mxc_nand.c 4423 4424- CONFIG_SYS_NDFC_EBC0_CFG 4425 Sets the EBC0_CFG register for the NDFC. If not defined 4426 a default value will be used. 4427 4428- CONFIG_SPD_EEPROM 4429 Get DDR timing information from an I2C EEPROM. Common 4430 with pluggable memory modules such as SODIMMs 4431 4432 SPD_EEPROM_ADDRESS 4433 I2C address of the SPD EEPROM 4434 4435- CONFIG_SYS_SPD_BUS_NUM 4436 If SPD EEPROM is on an I2C bus other than the first 4437 one, specify here. Note that the value must resolve 4438 to something your driver can deal with. 4439 4440- CONFIG_SYS_DDR_RAW_TIMING 4441 Get DDR timing information from other than SPD. Common with 4442 soldered DDR chips onboard without SPD. DDR raw timing 4443 parameters are extracted from datasheet and hard-coded into 4444 header files or board specific files. 4445 4446- CONFIG_FSL_DDR_INTERACTIVE 4447 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4448 4449- CONFIG_SYS_83XX_DDR_USES_CS0 4450 Only for 83xx systems. If specified, then DDR should 4451 be configured using CS0 and CS1 instead of CS2 and CS3. 4452 4453- CONFIG_ETHER_ON_FEC[12] 4454 Define to enable FEC[12] on a 8xx series processor. 4455 4456- CONFIG_FEC[12]_PHY 4457 Define to the hardcoded PHY address which corresponds 4458 to the given FEC; i. e. 4459 #define CONFIG_FEC1_PHY 4 4460 means that the PHY with address 4 is connected to FEC1 4461 4462 When set to -1, means to probe for first available. 4463 4464- CONFIG_FEC[12]_PHY_NORXERR 4465 The PHY does not have a RXERR line (RMII only). 4466 (so program the FEC to ignore it). 4467 4468- CONFIG_RMII 4469 Enable RMII mode for all FECs. 4470 Note that this is a global option, we can't 4471 have one FEC in standard MII mode and another in RMII mode. 4472 4473- CONFIG_CRC32_VERIFY 4474 Add a verify option to the crc32 command. 4475 The syntax is: 4476 4477 => crc32 -v <address> <count> <crc32> 4478 4479 Where address/count indicate a memory area 4480 and crc32 is the correct crc32 which the 4481 area should have. 4482 4483- CONFIG_LOOPW 4484 Add the "loopw" memory command. This only takes effect if 4485 the memory commands are activated globally (CONFIG_CMD_MEM). 4486 4487- CONFIG_MX_CYCLIC 4488 Add the "mdc" and "mwc" memory commands. These are cyclic 4489 "md/mw" commands. 4490 Examples: 4491 4492 => mdc.b 10 4 500 4493 This command will print 4 bytes (10,11,12,13) each 500 ms. 4494 4495 => mwc.l 100 12345678 10 4496 This command will write 12345678 to address 100 all 10 ms. 4497 4498 This only takes effect if the memory commands are activated 4499 globally (CONFIG_CMD_MEM). 4500 4501- CONFIG_SKIP_LOWLEVEL_INIT 4502 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4503 low level initializations (like setting up the memory 4504 controller) are omitted and/or U-Boot does not 4505 relocate itself into RAM. 4506 4507 Normally this variable MUST NOT be defined. The only 4508 exception is when U-Boot is loaded (to RAM) by some 4509 other boot loader or by a debugger which performs 4510 these initializations itself. 4511 4512- CONFIG_SPL_BUILD 4513 Modifies the behaviour of start.S when compiling a loader 4514 that is executed before the actual U-Boot. E.g. when 4515 compiling a NAND SPL. 4516 4517- CONFIG_TPL_BUILD 4518 Modifies the behaviour of start.S when compiling a loader 4519 that is executed after the SPL and before the actual U-Boot. 4520 It is loaded by the SPL. 4521 4522- CONFIG_SYS_MPC85XX_NO_RESETVEC 4523 Only for 85xx systems. If this variable is specified, the section 4524 .resetvec is not kept and the section .bootpg is placed in the 4525 previous 4k of the .text section. 4526 4527- CONFIG_ARCH_MAP_SYSMEM 4528 Generally U-Boot (and in particular the md command) uses 4529 effective address. It is therefore not necessary to regard 4530 U-Boot address as virtual addresses that need to be translated 4531 to physical addresses. However, sandbox requires this, since 4532 it maintains its own little RAM buffer which contains all 4533 addressable memory. This option causes some memory accesses 4534 to be mapped through map_sysmem() / unmap_sysmem(). 4535 4536- CONFIG_USE_ARCH_MEMCPY 4537 CONFIG_USE_ARCH_MEMSET 4538 If these options are used a optimized version of memcpy/memset will 4539 be used if available. These functions may be faster under some 4540 conditions but may increase the binary size. 4541 4542- CONFIG_X86_RESET_VECTOR 4543 If defined, the x86 reset vector code is included. This is not 4544 needed when U-Boot is running from Coreboot. 4545 4546- CONFIG_SYS_MPUCLK 4547 Defines the MPU clock speed (in MHz). 4548 4549 NOTE : currently only supported on AM335x platforms. 4550 4551- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4552 Enables the RTC32K OSC on AM33xx based plattforms 4553 4554- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4555 Option to disable subpage write in NAND driver 4556 driver that uses this: 4557 drivers/mtd/nand/davinci_nand.c 4558 4559Freescale QE/FMAN Firmware Support: 4560----------------------------------- 4561 4562The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4563loading of "firmware", which is encoded in the QE firmware binary format. 4564This firmware often needs to be loaded during U-Boot booting, so macros 4565are used to identify the storage device (NOR flash, SPI, etc) and the address 4566within that device. 4567 4568- CONFIG_SYS_FMAN_FW_ADDR 4569 The address in the storage device where the FMAN microcode is located. The 4570 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4571 is also specified. 4572 4573- CONFIG_SYS_QE_FW_ADDR 4574 The address in the storage device where the QE microcode is located. The 4575 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4576 is also specified. 4577 4578- CONFIG_SYS_QE_FMAN_FW_LENGTH 4579 The maximum possible size of the firmware. The firmware binary format 4580 has a field that specifies the actual size of the firmware, but it 4581 might not be possible to read any part of the firmware unless some 4582 local storage is allocated to hold the entire firmware first. 4583 4584- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4585 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4586 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4587 virtual address in NOR flash. 4588 4589- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4590 Specifies that QE/FMAN firmware is located in NAND flash. 4591 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4592 4593- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4594 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4595 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4596 4597- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 4598 Specifies that QE/FMAN firmware is located on the primary SPI 4599 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4600 4601- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4602 Specifies that QE/FMAN firmware is located in the remote (master) 4603 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4604 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4605 window->master inbound window->master LAW->the ucode address in 4606 master's memory space. 4607 4608Building the Software: 4609====================== 4610 4611Building U-Boot has been tested in several native build environments 4612and in many different cross environments. Of course we cannot support 4613all possibly existing versions of cross development tools in all 4614(potentially obsolete) versions. In case of tool chain problems we 4615recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4616which is extensively used to build and test U-Boot. 4617 4618If you are not using a native environment, it is assumed that you 4619have GNU cross compiling tools available in your path. In this case, 4620you must set the environment variable CROSS_COMPILE in your shell. 4621Note that no changes to the Makefile or any other source files are 4622necessary. For example using the ELDK on a 4xx CPU, please enter: 4623 4624 $ CROSS_COMPILE=ppc_4xx- 4625 $ export CROSS_COMPILE 4626 4627Note: If you wish to generate Windows versions of the utilities in 4628 the tools directory you can use the MinGW toolchain 4629 (http://www.mingw.org). Set your HOST tools to the MinGW 4630 toolchain and execute 'make tools'. For example: 4631 4632 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4633 4634 Binaries such as tools/mkimage.exe will be created which can 4635 be executed on computers running Windows. 4636 4637U-Boot is intended to be simple to build. After installing the 4638sources you must configure U-Boot for one specific board type. This 4639is done by typing: 4640 4641 make NAME_config 4642 4643where "NAME_config" is the name of one of the existing configu- 4644rations; see boards.cfg for supported names. 4645 4646Note: for some board special configuration names may exist; check if 4647 additional information is available from the board vendor; for 4648 instance, the TQM823L systems are available without (standard) 4649 or with LCD support. You can select such additional "features" 4650 when choosing the configuration, i. e. 4651 4652 make TQM823L_config 4653 - will configure for a plain TQM823L, i. e. no LCD support 4654 4655 make TQM823L_LCD_config 4656 - will configure for a TQM823L with U-Boot console on LCD 4657 4658 etc. 4659 4660 4661Finally, type "make all", and you should get some working U-Boot 4662images ready for download to / installation on your system: 4663 4664- "u-boot.bin" is a raw binary image 4665- "u-boot" is an image in ELF binary format 4666- "u-boot.srec" is in Motorola S-Record format 4667 4668By default the build is performed locally and the objects are saved 4669in the source directory. One of the two methods can be used to change 4670this behavior and build U-Boot to some external directory: 4671 46721. Add O= to the make command line invocations: 4673 4674 make O=/tmp/build distclean 4675 make O=/tmp/build NAME_config 4676 make O=/tmp/build all 4677 46782. Set environment variable BUILD_DIR to point to the desired location: 4679 4680 export BUILD_DIR=/tmp/build 4681 make distclean 4682 make NAME_config 4683 make all 4684 4685Note that the command line "O=" setting overrides the BUILD_DIR environment 4686variable. 4687 4688 4689Please be aware that the Makefiles assume you are using GNU make, so 4690for instance on NetBSD you might need to use "gmake" instead of 4691native "make". 4692 4693 4694If the system board that you have is not listed, then you will need 4695to port U-Boot to your hardware platform. To do this, follow these 4696steps: 4697 46981. Add a new configuration option for your board to the toplevel 4699 "boards.cfg" file, using the existing entries as examples. 4700 Follow the instructions there to keep the boards in order. 47012. Create a new directory to hold your board specific code. Add any 4702 files you need. In your board directory, you will need at least 4703 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 47043. Create a new configuration file "include/configs/<board>.h" for 4705 your board 47063. If you're porting U-Boot to a new CPU, then also create a new 4707 directory to hold your CPU specific code. Add any files you need. 47084. Run "make <board>_config" with your new name. 47095. Type "make", and you should get a working "u-boot.srec" file 4710 to be installed on your target system. 47116. Debug and solve any problems that might arise. 4712 [Of course, this last step is much harder than it sounds.] 4713 4714 4715Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4716============================================================== 4717 4718If you have modified U-Boot sources (for instance added a new board 4719or support for new devices, a new CPU, etc.) you are expected to 4720provide feedback to the other developers. The feedback normally takes 4721the form of a "patch", i. e. a context diff against a certain (latest 4722official or latest in the git repository) version of U-Boot sources. 4723 4724But before you submit such a patch, please verify that your modifi- 4725cation did not break existing code. At least make sure that *ALL* of 4726the supported boards compile WITHOUT ANY compiler warnings. To do so, 4727just run the "MAKEALL" script, which will configure and build U-Boot 4728for ALL supported system. Be warned, this will take a while. You can 4729select which (cross) compiler to use by passing a `CROSS_COMPILE' 4730environment variable to the script, i. e. to use the ELDK cross tools 4731you can type 4732 4733 CROSS_COMPILE=ppc_8xx- MAKEALL 4734 4735or to build on a native PowerPC system you can type 4736 4737 CROSS_COMPILE=' ' MAKEALL 4738 4739When using the MAKEALL script, the default behaviour is to build 4740U-Boot in the source directory. This location can be changed by 4741setting the BUILD_DIR environment variable. Also, for each target 4742built, the MAKEALL script saves two log files (<target>.ERR and 4743<target>.MAKEALL) in the <source dir>/LOG directory. This default 4744location can be changed by setting the MAKEALL_LOGDIR environment 4745variable. For example: 4746 4747 export BUILD_DIR=/tmp/build 4748 export MAKEALL_LOGDIR=/tmp/log 4749 CROSS_COMPILE=ppc_8xx- MAKEALL 4750 4751With the above settings build objects are saved in the /tmp/build, 4752log files are saved in the /tmp/log and the source tree remains clean 4753during the whole build process. 4754 4755 4756See also "U-Boot Porting Guide" below. 4757 4758 4759Monitor Commands - Overview: 4760============================ 4761 4762go - start application at address 'addr' 4763run - run commands in an environment variable 4764bootm - boot application image from memory 4765bootp - boot image via network using BootP/TFTP protocol 4766bootz - boot zImage from memory 4767tftpboot- boot image via network using TFTP protocol 4768 and env variables "ipaddr" and "serverip" 4769 (and eventually "gatewayip") 4770tftpput - upload a file via network using TFTP protocol 4771rarpboot- boot image via network using RARP/TFTP protocol 4772diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4773loads - load S-Record file over serial line 4774loadb - load binary file over serial line (kermit mode) 4775md - memory display 4776mm - memory modify (auto-incrementing) 4777nm - memory modify (constant address) 4778mw - memory write (fill) 4779cp - memory copy 4780cmp - memory compare 4781crc32 - checksum calculation 4782i2c - I2C sub-system 4783sspi - SPI utility commands 4784base - print or set address offset 4785printenv- print environment variables 4786setenv - set environment variables 4787saveenv - save environment variables to persistent storage 4788protect - enable or disable FLASH write protection 4789erase - erase FLASH memory 4790flinfo - print FLASH memory information 4791nand - NAND memory operations (see doc/README.nand) 4792bdinfo - print Board Info structure 4793iminfo - print header information for application image 4794coninfo - print console devices and informations 4795ide - IDE sub-system 4796loop - infinite loop on address range 4797loopw - infinite write loop on address range 4798mtest - simple RAM test 4799icache - enable or disable instruction cache 4800dcache - enable or disable data cache 4801reset - Perform RESET of the CPU 4802echo - echo args to console 4803version - print monitor version 4804help - print online help 4805? - alias for 'help' 4806 4807 4808Monitor Commands - Detailed Description: 4809======================================== 4810 4811TODO. 4812 4813For now: just type "help <command>". 4814 4815 4816Environment Variables: 4817====================== 4818 4819U-Boot supports user configuration using Environment Variables which 4820can be made persistent by saving to Flash memory. 4821 4822Environment Variables are set using "setenv", printed using 4823"printenv", and saved to Flash using "saveenv". Using "setenv" 4824without a value can be used to delete a variable from the 4825environment. As long as you don't save the environment you are 4826working with an in-memory copy. In case the Flash area containing the 4827environment is erased by accident, a default environment is provided. 4828 4829Some configuration options can be set using Environment Variables. 4830 4831List of environment variables (most likely not complete): 4832 4833 baudrate - see CONFIG_BAUDRATE 4834 4835 bootdelay - see CONFIG_BOOTDELAY 4836 4837 bootcmd - see CONFIG_BOOTCOMMAND 4838 4839 bootargs - Boot arguments when booting an RTOS image 4840 4841 bootfile - Name of the image to load with TFTP 4842 4843 bootm_low - Memory range available for image processing in the bootm 4844 command can be restricted. This variable is given as 4845 a hexadecimal number and defines lowest address allowed 4846 for use by the bootm command. See also "bootm_size" 4847 environment variable. Address defined by "bootm_low" is 4848 also the base of the initial memory mapping for the Linux 4849 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4850 bootm_mapsize. 4851 4852 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4853 This variable is given as a hexadecimal number and it 4854 defines the size of the memory region starting at base 4855 address bootm_low that is accessible by the Linux kernel 4856 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4857 as the default value if it is defined, and bootm_size is 4858 used otherwise. 4859 4860 bootm_size - Memory range available for image processing in the bootm 4861 command can be restricted. This variable is given as 4862 a hexadecimal number and defines the size of the region 4863 allowed for use by the bootm command. See also "bootm_low" 4864 environment variable. 4865 4866 updatefile - Location of the software update file on a TFTP server, used 4867 by the automatic software update feature. Please refer to 4868 documentation in doc/README.update for more details. 4869 4870 autoload - if set to "no" (any string beginning with 'n'), 4871 "bootp" will just load perform a lookup of the 4872 configuration from the BOOTP server, but not try to 4873 load any image using TFTP 4874 4875 autostart - if set to "yes", an image loaded using the "bootp", 4876 "rarpboot", "tftpboot" or "diskboot" commands will 4877 be automatically started (by internally calling 4878 "bootm") 4879 4880 If set to "no", a standalone image passed to the 4881 "bootm" command will be copied to the load address 4882 (and eventually uncompressed), but NOT be started. 4883 This can be used to load and uncompress arbitrary 4884 data. 4885 4886 fdt_high - if set this restricts the maximum address that the 4887 flattened device tree will be copied into upon boot. 4888 For example, if you have a system with 1 GB memory 4889 at physical address 0x10000000, while Linux kernel 4890 only recognizes the first 704 MB as low memory, you 4891 may need to set fdt_high as 0x3C000000 to have the 4892 device tree blob be copied to the maximum address 4893 of the 704 MB low memory, so that Linux kernel can 4894 access it during the boot procedure. 4895 4896 If this is set to the special value 0xFFFFFFFF then 4897 the fdt will not be copied at all on boot. For this 4898 to work it must reside in writable memory, have 4899 sufficient padding on the end of it for u-boot to 4900 add the information it needs into it, and the memory 4901 must be accessible by the kernel. 4902 4903 fdtcontroladdr- if set this is the address of the control flattened 4904 device tree used by U-Boot when CONFIG_OF_CONTROL is 4905 defined. 4906 4907 i2cfast - (PPC405GP|PPC405EP only) 4908 if set to 'y' configures Linux I2C driver for fast 4909 mode (400kHZ). This environment variable is used in 4910 initialization code. So, for changes to be effective 4911 it must be saved and board must be reset. 4912 4913 initrd_high - restrict positioning of initrd images: 4914 If this variable is not set, initrd images will be 4915 copied to the highest possible address in RAM; this 4916 is usually what you want since it allows for 4917 maximum initrd size. If for some reason you want to 4918 make sure that the initrd image is loaded below the 4919 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4920 variable to a value of "no" or "off" or "0". 4921 Alternatively, you can set it to a maximum upper 4922 address to use (U-Boot will still check that it 4923 does not overwrite the U-Boot stack and data). 4924 4925 For instance, when you have a system with 16 MB 4926 RAM, and want to reserve 4 MB from use by Linux, 4927 you can do this by adding "mem=12M" to the value of 4928 the "bootargs" variable. However, now you must make 4929 sure that the initrd image is placed in the first 4930 12 MB as well - this can be done with 4931 4932 setenv initrd_high 00c00000 4933 4934 If you set initrd_high to 0xFFFFFFFF, this is an 4935 indication to U-Boot that all addresses are legal 4936 for the Linux kernel, including addresses in flash 4937 memory. In this case U-Boot will NOT COPY the 4938 ramdisk at all. This may be useful to reduce the 4939 boot time on your system, but requires that this 4940 feature is supported by your Linux kernel. 4941 4942 ipaddr - IP address; needed for tftpboot command 4943 4944 loadaddr - Default load address for commands like "bootp", 4945 "rarpboot", "tftpboot", "loadb" or "diskboot" 4946 4947 loads_echo - see CONFIG_LOADS_ECHO 4948 4949 serverip - TFTP server IP address; needed for tftpboot command 4950 4951 bootretry - see CONFIG_BOOT_RETRY_TIME 4952 4953 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4954 4955 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4956 4957 ethprime - controls which interface is used first. 4958 4959 ethact - controls which interface is currently active. 4960 For example you can do the following 4961 4962 => setenv ethact FEC 4963 => ping 192.168.0.1 # traffic sent on FEC 4964 => setenv ethact SCC 4965 => ping 10.0.0.1 # traffic sent on SCC 4966 4967 ethrotate - When set to "no" U-Boot does not go through all 4968 available network interfaces. 4969 It just stays at the currently selected interface. 4970 4971 netretry - When set to "no" each network operation will 4972 either succeed or fail without retrying. 4973 When set to "once" the network operation will 4974 fail when all the available network interfaces 4975 are tried once without success. 4976 Useful on scripts which control the retry operation 4977 themselves. 4978 4979 npe_ucode - set load address for the NPE microcode 4980 4981 silent_linux - If set then linux will be told to boot silently, by 4982 changing the console to be empty. If "yes" it will be 4983 made silent. If "no" it will not be made silent. If 4984 unset, then it will be made silent if the U-Boot console 4985 is silent. 4986 4987 tftpsrcport - If this is set, the value is used for TFTP's 4988 UDP source port. 4989 4990 tftpdstport - If this is set, the value is used for TFTP's UDP 4991 destination port instead of the Well Know Port 69. 4992 4993 tftpblocksize - Block size to use for TFTP transfers; if not set, 4994 we use the TFTP server's default block size 4995 4996 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4997 seconds, minimum value is 1000 = 1 second). Defines 4998 when a packet is considered to be lost so it has to 4999 be retransmitted. The default is 5000 = 5 seconds. 5000 Lowering this value may make downloads succeed 5001 faster in networks with high packet loss rates or 5002 with unreliable TFTP servers. 5003 5004 vlan - When set to a value < 4095 the traffic over 5005 Ethernet is encapsulated/received over 802.1q 5006 VLAN tagged frames. 5007 5008The following image location variables contain the location of images 5009used in booting. The "Image" column gives the role of the image and is 5010not an environment variable name. The other columns are environment 5011variable names. "File Name" gives the name of the file on a TFTP 5012server, "RAM Address" gives the location in RAM the image will be 5013loaded to, and "Flash Location" gives the image's address in NOR 5014flash or offset in NAND flash. 5015 5016*Note* - these variables don't have to be defined for all boards, some 5017boards currenlty use other variables for these purposes, and some 5018boards use these variables for other purposes. 5019 5020Image File Name RAM Address Flash Location 5021----- --------- ----------- -------------- 5022u-boot u-boot u-boot_addr_r u-boot_addr 5023Linux kernel bootfile kernel_addr_r kernel_addr 5024device tree blob fdtfile fdt_addr_r fdt_addr 5025ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5026 5027The following environment variables may be used and automatically 5028updated by the network boot commands ("bootp" and "rarpboot"), 5029depending the information provided by your boot server: 5030 5031 bootfile - see above 5032 dnsip - IP address of your Domain Name Server 5033 dnsip2 - IP address of your secondary Domain Name Server 5034 gatewayip - IP address of the Gateway (Router) to use 5035 hostname - Target hostname 5036 ipaddr - see above 5037 netmask - Subnet Mask 5038 rootpath - Pathname of the root filesystem on the NFS server 5039 serverip - see above 5040 5041 5042There are two special Environment Variables: 5043 5044 serial# - contains hardware identification information such 5045 as type string and/or serial number 5046 ethaddr - Ethernet address 5047 5048These variables can be set only once (usually during manufacturing of 5049the board). U-Boot refuses to delete or overwrite these variables 5050once they have been set once. 5051 5052 5053Further special Environment Variables: 5054 5055 ver - Contains the U-Boot version string as printed 5056 with the "version" command. This variable is 5057 readonly (see CONFIG_VERSION_VARIABLE). 5058 5059 5060Please note that changes to some configuration parameters may take 5061only effect after the next boot (yes, that's just like Windoze :-). 5062 5063 5064Callback functions for environment variables: 5065--------------------------------------------- 5066 5067For some environment variables, the behavior of u-boot needs to change 5068when their values are changed. This functionailty allows functions to 5069be associated with arbitrary variables. On creation, overwrite, or 5070deletion, the callback will provide the opportunity for some side 5071effect to happen or for the change to be rejected. 5072 5073The callbacks are named and associated with a function using the 5074U_BOOT_ENV_CALLBACK macro in your board or driver code. 5075 5076These callbacks are associated with variables in one of two ways. The 5077static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5078in the board configuration to a string that defines a list of 5079associations. The list must be in the following format: 5080 5081 entry = variable_name[:callback_name] 5082 list = entry[,list] 5083 5084If the callback name is not specified, then the callback is deleted. 5085Spaces are also allowed anywhere in the list. 5086 5087Callbacks can also be associated by defining the ".callbacks" variable 5088with the same list format above. Any association in ".callbacks" will 5089override any association in the static list. You can define 5090CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5091".callbacks" envirnoment variable in the default or embedded environment. 5092 5093 5094Command Line Parsing: 5095===================== 5096 5097There are two different command line parsers available with U-Boot: 5098the old "simple" one, and the much more powerful "hush" shell: 5099 5100Old, simple command line parser: 5101-------------------------------- 5102 5103- supports environment variables (through setenv / saveenv commands) 5104- several commands on one line, separated by ';' 5105- variable substitution using "... ${name} ..." syntax 5106- special characters ('$', ';') can be escaped by prefixing with '\', 5107 for example: 5108 setenv bootcmd bootm \${address} 5109- You can also escape text by enclosing in single apostrophes, for example: 5110 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5111 5112Hush shell: 5113----------- 5114 5115- similar to Bourne shell, with control structures like 5116 if...then...else...fi, for...do...done; while...do...done, 5117 until...do...done, ... 5118- supports environment ("global") variables (through setenv / saveenv 5119 commands) and local shell variables (through standard shell syntax 5120 "name=value"); only environment variables can be used with "run" 5121 command 5122 5123General rules: 5124-------------- 5125 5126(1) If a command line (or an environment variable executed by a "run" 5127 command) contains several commands separated by semicolon, and 5128 one of these commands fails, then the remaining commands will be 5129 executed anyway. 5130 5131(2) If you execute several variables with one call to run (i. e. 5132 calling run with a list of variables as arguments), any failing 5133 command will cause "run" to terminate, i. e. the remaining 5134 variables are not executed. 5135 5136Note for Redundant Ethernet Interfaces: 5137======================================= 5138 5139Some boards come with redundant Ethernet interfaces; U-Boot supports 5140such configurations and is capable of automatic selection of a 5141"working" interface when needed. MAC assignment works as follows: 5142 5143Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5144MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5145"eth1addr" (=>eth1), "eth2addr", ... 5146 5147If the network interface stores some valid MAC address (for instance 5148in SROM), this is used as default address if there is NO correspon- 5149ding setting in the environment; if the corresponding environment 5150variable is set, this overrides the settings in the card; that means: 5151 5152o If the SROM has a valid MAC address, and there is no address in the 5153 environment, the SROM's address is used. 5154 5155o If there is no valid address in the SROM, and a definition in the 5156 environment exists, then the value from the environment variable is 5157 used. 5158 5159o If both the SROM and the environment contain a MAC address, and 5160 both addresses are the same, this MAC address is used. 5161 5162o If both the SROM and the environment contain a MAC address, and the 5163 addresses differ, the value from the environment is used and a 5164 warning is printed. 5165 5166o If neither SROM nor the environment contain a MAC address, an error 5167 is raised. 5168 5169If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5170will be programmed into hardware as part of the initialization process. This 5171may be skipped by setting the appropriate 'ethmacskip' environment variable. 5172The naming convention is as follows: 5173"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5174 5175Image Formats: 5176============== 5177 5178U-Boot is capable of booting (and performing other auxiliary operations on) 5179images in two formats: 5180 5181New uImage format (FIT) 5182----------------------- 5183 5184Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5185to Flattened Device Tree). It allows the use of images with multiple 5186components (several kernels, ramdisks, etc.), with contents protected by 5187SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5188 5189 5190Old uImage format 5191----------------- 5192 5193Old image format is based on binary files which can be basically anything, 5194preceded by a special header; see the definitions in include/image.h for 5195details; basically, the header defines the following image properties: 5196 5197* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5198 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5199 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5200 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5201 INTEGRITY). 5202* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5203 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5204 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5205* Compression Type (uncompressed, gzip, bzip2) 5206* Load Address 5207* Entry Point 5208* Image Name 5209* Image Timestamp 5210 5211The header is marked by a special Magic Number, and both the header 5212and the data portions of the image are secured against corruption by 5213CRC32 checksums. 5214 5215 5216Linux Support: 5217============== 5218 5219Although U-Boot should support any OS or standalone application 5220easily, the main focus has always been on Linux during the design of 5221U-Boot. 5222 5223U-Boot includes many features that so far have been part of some 5224special "boot loader" code within the Linux kernel. Also, any 5225"initrd" images to be used are no longer part of one big Linux image; 5226instead, kernel and "initrd" are separate images. This implementation 5227serves several purposes: 5228 5229- the same features can be used for other OS or standalone 5230 applications (for instance: using compressed images to reduce the 5231 Flash memory footprint) 5232 5233- it becomes much easier to port new Linux kernel versions because 5234 lots of low-level, hardware dependent stuff are done by U-Boot 5235 5236- the same Linux kernel image can now be used with different "initrd" 5237 images; of course this also means that different kernel images can 5238 be run with the same "initrd". This makes testing easier (you don't 5239 have to build a new "zImage.initrd" Linux image when you just 5240 change a file in your "initrd"). Also, a field-upgrade of the 5241 software is easier now. 5242 5243 5244Linux HOWTO: 5245============ 5246 5247Porting Linux to U-Boot based systems: 5248--------------------------------------- 5249 5250U-Boot cannot save you from doing all the necessary modifications to 5251configure the Linux device drivers for use with your target hardware 5252(no, we don't intend to provide a full virtual machine interface to 5253Linux :-). 5254 5255But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5256 5257Just make sure your machine specific header file (for instance 5258include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5259Information structure as we define in include/asm-<arch>/u-boot.h, 5260and make sure that your definition of IMAP_ADDR uses the same value 5261as your U-Boot configuration in CONFIG_SYS_IMMR. 5262 5263 5264Configuring the Linux kernel: 5265----------------------------- 5266 5267No specific requirements for U-Boot. Make sure you have some root 5268device (initial ramdisk, NFS) for your target system. 5269 5270 5271Building a Linux Image: 5272----------------------- 5273 5274With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5275not used. If you use recent kernel source, a new build target 5276"uImage" will exist which automatically builds an image usable by 5277U-Boot. Most older kernels also have support for a "pImage" target, 5278which was introduced for our predecessor project PPCBoot and uses a 5279100% compatible format. 5280 5281Example: 5282 5283 make TQM850L_config 5284 make oldconfig 5285 make dep 5286 make uImage 5287 5288The "uImage" build target uses a special tool (in 'tools/mkimage') to 5289encapsulate a compressed Linux kernel image with header information, 5290CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5291 5292* build a standard "vmlinux" kernel image (in ELF binary format): 5293 5294* convert the kernel into a raw binary image: 5295 5296 ${CROSS_COMPILE}-objcopy -O binary \ 5297 -R .note -R .comment \ 5298 -S vmlinux linux.bin 5299 5300* compress the binary image: 5301 5302 gzip -9 linux.bin 5303 5304* package compressed binary image for U-Boot: 5305 5306 mkimage -A ppc -O linux -T kernel -C gzip \ 5307 -a 0 -e 0 -n "Linux Kernel Image" \ 5308 -d linux.bin.gz uImage 5309 5310 5311The "mkimage" tool can also be used to create ramdisk images for use 5312with U-Boot, either separated from the Linux kernel image, or 5313combined into one file. "mkimage" encapsulates the images with a 64 5314byte header containing information about target architecture, 5315operating system, image type, compression method, entry points, time 5316stamp, CRC32 checksums, etc. 5317 5318"mkimage" can be called in two ways: to verify existing images and 5319print the header information, or to build new images. 5320 5321In the first form (with "-l" option) mkimage lists the information 5322contained in the header of an existing U-Boot image; this includes 5323checksum verification: 5324 5325 tools/mkimage -l image 5326 -l ==> list image header information 5327 5328The second form (with "-d" option) is used to build a U-Boot image 5329from a "data file" which is used as image payload: 5330 5331 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5332 -n name -d data_file image 5333 -A ==> set architecture to 'arch' 5334 -O ==> set operating system to 'os' 5335 -T ==> set image type to 'type' 5336 -C ==> set compression type 'comp' 5337 -a ==> set load address to 'addr' (hex) 5338 -e ==> set entry point to 'ep' (hex) 5339 -n ==> set image name to 'name' 5340 -d ==> use image data from 'datafile' 5341 5342Right now, all Linux kernels for PowerPC systems use the same load 5343address (0x00000000), but the entry point address depends on the 5344kernel version: 5345 5346- 2.2.x kernels have the entry point at 0x0000000C, 5347- 2.3.x and later kernels have the entry point at 0x00000000. 5348 5349So a typical call to build a U-Boot image would read: 5350 5351 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5352 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5353 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5354 > examples/uImage.TQM850L 5355 Image Name: 2.4.4 kernel for TQM850L 5356 Created: Wed Jul 19 02:34:59 2000 5357 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5358 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5359 Load Address: 0x00000000 5360 Entry Point: 0x00000000 5361 5362To verify the contents of the image (or check for corruption): 5363 5364 -> tools/mkimage -l examples/uImage.TQM850L 5365 Image Name: 2.4.4 kernel for TQM850L 5366 Created: Wed Jul 19 02:34:59 2000 5367 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5368 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5369 Load Address: 0x00000000 5370 Entry Point: 0x00000000 5371 5372NOTE: for embedded systems where boot time is critical you can trade 5373speed for memory and install an UNCOMPRESSED image instead: this 5374needs more space in Flash, but boots much faster since it does not 5375need to be uncompressed: 5376 5377 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5378 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5379 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5380 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5381 > examples/uImage.TQM850L-uncompressed 5382 Image Name: 2.4.4 kernel for TQM850L 5383 Created: Wed Jul 19 02:34:59 2000 5384 Image Type: PowerPC Linux Kernel Image (uncompressed) 5385 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5386 Load Address: 0x00000000 5387 Entry Point: 0x00000000 5388 5389 5390Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5391when your kernel is intended to use an initial ramdisk: 5392 5393 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5394 > -A ppc -O linux -T ramdisk -C gzip \ 5395 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5396 Image Name: Simple Ramdisk Image 5397 Created: Wed Jan 12 14:01:50 2000 5398 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5399 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5400 Load Address: 0x00000000 5401 Entry Point: 0x00000000 5402 5403The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5404option performs the converse operation of the mkimage's second form (the "-d" 5405option). Given an image built by mkimage, the dumpimage extracts a "data file" 5406from the image: 5407 5408 tools/dumpimage -i image -p position data_file 5409 -i ==> extract from the 'image' a specific 'data_file', \ 5410 indexed by 'position' 5411 5412 5413Installing a Linux Image: 5414------------------------- 5415 5416To downloading a U-Boot image over the serial (console) interface, 5417you must convert the image to S-Record format: 5418 5419 objcopy -I binary -O srec examples/image examples/image.srec 5420 5421The 'objcopy' does not understand the information in the U-Boot 5422image header, so the resulting S-Record file will be relative to 5423address 0x00000000. To load it to a given address, you need to 5424specify the target address as 'offset' parameter with the 'loads' 5425command. 5426 5427Example: install the image to address 0x40100000 (which on the 5428TQM8xxL is in the first Flash bank): 5429 5430 => erase 40100000 401FFFFF 5431 5432 .......... done 5433 Erased 8 sectors 5434 5435 => loads 40100000 5436 ## Ready for S-Record download ... 5437 ~>examples/image.srec 5438 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5439 ... 5440 15989 15990 15991 15992 5441 [file transfer complete] 5442 [connected] 5443 ## Start Addr = 0x00000000 5444 5445 5446You can check the success of the download using the 'iminfo' command; 5447this includes a checksum verification so you can be sure no data 5448corruption happened: 5449 5450 => imi 40100000 5451 5452 ## Checking Image at 40100000 ... 5453 Image Name: 2.2.13 for initrd on TQM850L 5454 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5455 Data Size: 335725 Bytes = 327 kB = 0 MB 5456 Load Address: 00000000 5457 Entry Point: 0000000c 5458 Verifying Checksum ... OK 5459 5460 5461Boot Linux: 5462----------- 5463 5464The "bootm" command is used to boot an application that is stored in 5465memory (RAM or Flash). In case of a Linux kernel image, the contents 5466of the "bootargs" environment variable is passed to the kernel as 5467parameters. You can check and modify this variable using the 5468"printenv" and "setenv" commands: 5469 5470 5471 => printenv bootargs 5472 bootargs=root=/dev/ram 5473 5474 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5475 5476 => printenv bootargs 5477 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5478 5479 => bootm 40020000 5480 ## Booting Linux kernel at 40020000 ... 5481 Image Name: 2.2.13 for NFS on TQM850L 5482 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5483 Data Size: 381681 Bytes = 372 kB = 0 MB 5484 Load Address: 00000000 5485 Entry Point: 0000000c 5486 Verifying Checksum ... OK 5487 Uncompressing Kernel Image ... OK 5488 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 5489 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5490 time_init: decrementer frequency = 187500000/60 5491 Calibrating delay loop... 49.77 BogoMIPS 5492 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5493 ... 5494 5495If you want to boot a Linux kernel with initial RAM disk, you pass 5496the memory addresses of both the kernel and the initrd image (PPBCOOT 5497format!) to the "bootm" command: 5498 5499 => imi 40100000 40200000 5500 5501 ## Checking Image at 40100000 ... 5502 Image Name: 2.2.13 for initrd on TQM850L 5503 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5504 Data Size: 335725 Bytes = 327 kB = 0 MB 5505 Load Address: 00000000 5506 Entry Point: 0000000c 5507 Verifying Checksum ... OK 5508 5509 ## Checking Image at 40200000 ... 5510 Image Name: Simple Ramdisk Image 5511 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5512 Data Size: 566530 Bytes = 553 kB = 0 MB 5513 Load Address: 00000000 5514 Entry Point: 00000000 5515 Verifying Checksum ... OK 5516 5517 => bootm 40100000 40200000 5518 ## Booting Linux kernel at 40100000 ... 5519 Image Name: 2.2.13 for initrd on TQM850L 5520 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5521 Data Size: 335725 Bytes = 327 kB = 0 MB 5522 Load Address: 00000000 5523 Entry Point: 0000000c 5524 Verifying Checksum ... OK 5525 Uncompressing Kernel Image ... OK 5526 ## Loading RAMDisk Image at 40200000 ... 5527 Image Name: Simple Ramdisk Image 5528 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5529 Data Size: 566530 Bytes = 553 kB = 0 MB 5530 Load Address: 00000000 5531 Entry Point: 00000000 5532 Verifying Checksum ... OK 5533 Loading Ramdisk ... OK 5534 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 5535 Boot arguments: root=/dev/ram 5536 time_init: decrementer frequency = 187500000/60 5537 Calibrating delay loop... 49.77 BogoMIPS 5538 ... 5539 RAMDISK: Compressed image found at block 0 5540 VFS: Mounted root (ext2 filesystem). 5541 5542 bash# 5543 5544Boot Linux and pass a flat device tree: 5545----------- 5546 5547First, U-Boot must be compiled with the appropriate defines. See the section 5548titled "Linux Kernel Interface" above for a more in depth explanation. The 5549following is an example of how to start a kernel and pass an updated 5550flat device tree: 5551 5552=> print oftaddr 5553oftaddr=0x300000 5554=> print oft 5555oft=oftrees/mpc8540ads.dtb 5556=> tftp $oftaddr $oft 5557Speed: 1000, full duplex 5558Using TSEC0 device 5559TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5560Filename 'oftrees/mpc8540ads.dtb'. 5561Load address: 0x300000 5562Loading: # 5563done 5564Bytes transferred = 4106 (100a hex) 5565=> tftp $loadaddr $bootfile 5566Speed: 1000, full duplex 5567Using TSEC0 device 5568TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5569Filename 'uImage'. 5570Load address: 0x200000 5571Loading:############ 5572done 5573Bytes transferred = 1029407 (fb51f hex) 5574=> print loadaddr 5575loadaddr=200000 5576=> print oftaddr 5577oftaddr=0x300000 5578=> bootm $loadaddr - $oftaddr 5579## Booting image at 00200000 ... 5580 Image Name: Linux-2.6.17-dirty 5581 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5582 Data Size: 1029343 Bytes = 1005.2 kB 5583 Load Address: 00000000 5584 Entry Point: 00000000 5585 Verifying Checksum ... OK 5586 Uncompressing Kernel Image ... OK 5587Booting using flat device tree at 0x300000 5588Using MPC85xx ADS machine description 5589Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5590[snip] 5591 5592 5593More About U-Boot Image Types: 5594------------------------------ 5595 5596U-Boot supports the following image types: 5597 5598 "Standalone Programs" are directly runnable in the environment 5599 provided by U-Boot; it is expected that (if they behave 5600 well) you can continue to work in U-Boot after return from 5601 the Standalone Program. 5602 "OS Kernel Images" are usually images of some Embedded OS which 5603 will take over control completely. Usually these programs 5604 will install their own set of exception handlers, device 5605 drivers, set up the MMU, etc. - this means, that you cannot 5606 expect to re-enter U-Boot except by resetting the CPU. 5607 "RAMDisk Images" are more or less just data blocks, and their 5608 parameters (address, size) are passed to an OS kernel that is 5609 being started. 5610 "Multi-File Images" contain several images, typically an OS 5611 (Linux) kernel image and one or more data images like 5612 RAMDisks. This construct is useful for instance when you want 5613 to boot over the network using BOOTP etc., where the boot 5614 server provides just a single image file, but you want to get 5615 for instance an OS kernel and a RAMDisk image. 5616 5617 "Multi-File Images" start with a list of image sizes, each 5618 image size (in bytes) specified by an "uint32_t" in network 5619 byte order. This list is terminated by an "(uint32_t)0". 5620 Immediately after the terminating 0 follow the images, one by 5621 one, all aligned on "uint32_t" boundaries (size rounded up to 5622 a multiple of 4 bytes). 5623 5624 "Firmware Images" are binary images containing firmware (like 5625 U-Boot or FPGA images) which usually will be programmed to 5626 flash memory. 5627 5628 "Script files" are command sequences that will be executed by 5629 U-Boot's command interpreter; this feature is especially 5630 useful when you configure U-Boot to use a real shell (hush) 5631 as command interpreter. 5632 5633Booting the Linux zImage: 5634------------------------- 5635 5636On some platforms, it's possible to boot Linux zImage. This is done 5637using the "bootz" command. The syntax of "bootz" command is the same 5638as the syntax of "bootm" command. 5639 5640Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5641kernel with raw initrd images. The syntax is slightly different, the 5642address of the initrd must be augmented by it's size, in the following 5643format: "<initrd addres>:<initrd size>". 5644 5645 5646Standalone HOWTO: 5647================= 5648 5649One of the features of U-Boot is that you can dynamically load and 5650run "standalone" applications, which can use some resources of 5651U-Boot like console I/O functions or interrupt services. 5652 5653Two simple examples are included with the sources: 5654 5655"Hello World" Demo: 5656------------------- 5657 5658'examples/hello_world.c' contains a small "Hello World" Demo 5659application; it is automatically compiled when you build U-Boot. 5660It's configured to run at address 0x00040004, so you can play with it 5661like that: 5662 5663 => loads 5664 ## Ready for S-Record download ... 5665 ~>examples/hello_world.srec 5666 1 2 3 4 5 6 7 8 9 10 11 ... 5667 [file transfer complete] 5668 [connected] 5669 ## Start Addr = 0x00040004 5670 5671 => go 40004 Hello World! This is a test. 5672 ## Starting application at 0x00040004 ... 5673 Hello World 5674 argc = 7 5675 argv[0] = "40004" 5676 argv[1] = "Hello" 5677 argv[2] = "World!" 5678 argv[3] = "This" 5679 argv[4] = "is" 5680 argv[5] = "a" 5681 argv[6] = "test." 5682 argv[7] = "<NULL>" 5683 Hit any key to exit ... 5684 5685 ## Application terminated, rc = 0x0 5686 5687Another example, which demonstrates how to register a CPM interrupt 5688handler with the U-Boot code, can be found in 'examples/timer.c'. 5689Here, a CPM timer is set up to generate an interrupt every second. 5690The interrupt service routine is trivial, just printing a '.' 5691character, but this is just a demo program. The application can be 5692controlled by the following keys: 5693 5694 ? - print current values og the CPM Timer registers 5695 b - enable interrupts and start timer 5696 e - stop timer and disable interrupts 5697 q - quit application 5698 5699 => loads 5700 ## Ready for S-Record download ... 5701 ~>examples/timer.srec 5702 1 2 3 4 5 6 7 8 9 10 11 ... 5703 [file transfer complete] 5704 [connected] 5705 ## Start Addr = 0x00040004 5706 5707 => go 40004 5708 ## Starting application at 0x00040004 ... 5709 TIMERS=0xfff00980 5710 Using timer 1 5711 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5712 5713Hit 'b': 5714 [q, b, e, ?] Set interval 1000000 us 5715 Enabling timer 5716Hit '?': 5717 [q, b, e, ?] ........ 5718 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5719Hit '?': 5720 [q, b, e, ?] . 5721 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5722Hit '?': 5723 [q, b, e, ?] . 5724 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5725Hit '?': 5726 [q, b, e, ?] . 5727 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5728Hit 'e': 5729 [q, b, e, ?] ...Stopping timer 5730Hit 'q': 5731 [q, b, e, ?] ## Application terminated, rc = 0x0 5732 5733 5734Minicom warning: 5735================ 5736 5737Over time, many people have reported problems when trying to use the 5738"minicom" terminal emulation program for serial download. I (wd) 5739consider minicom to be broken, and recommend not to use it. Under 5740Unix, I recommend to use C-Kermit for general purpose use (and 5741especially for kermit binary protocol download ("loadb" command), and 5742use "cu" for S-Record download ("loads" command). See 5743http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5744for help with kermit. 5745 5746 5747Nevertheless, if you absolutely want to use it try adding this 5748configuration to your "File transfer protocols" section: 5749 5750 Name Program Name U/D FullScr IO-Red. Multi 5751 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5752 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5753 5754 5755NetBSD Notes: 5756============= 5757 5758Starting at version 0.9.2, U-Boot supports NetBSD both as host 5759(build U-Boot) and target system (boots NetBSD/mpc8xx). 5760 5761Building requires a cross environment; it is known to work on 5762NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5763need gmake since the Makefiles are not compatible with BSD make). 5764Note that the cross-powerpc package does not install include files; 5765attempting to build U-Boot will fail because <machine/ansi.h> is 5766missing. This file has to be installed and patched manually: 5767 5768 # cd /usr/pkg/cross/powerpc-netbsd/include 5769 # mkdir powerpc 5770 # ln -s powerpc machine 5771 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5772 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5773 5774Native builds *don't* work due to incompatibilities between native 5775and U-Boot include files. 5776 5777Booting assumes that (the first part of) the image booted is a 5778stage-2 loader which in turn loads and then invokes the kernel 5779proper. Loader sources will eventually appear in the NetBSD source 5780tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5781meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5782 5783 5784Implementation Internals: 5785========================= 5786 5787The following is not intended to be a complete description of every 5788implementation detail. However, it should help to understand the 5789inner workings of U-Boot and make it easier to port it to custom 5790hardware. 5791 5792 5793Initial Stack, Global Data: 5794--------------------------- 5795 5796The implementation of U-Boot is complicated by the fact that U-Boot 5797starts running out of ROM (flash memory), usually without access to 5798system RAM (because the memory controller is not initialized yet). 5799This means that we don't have writable Data or BSS segments, and BSS 5800is not initialized as zero. To be able to get a C environment working 5801at all, we have to allocate at least a minimal stack. Implementation 5802options for this are defined and restricted by the CPU used: Some CPU 5803models provide on-chip memory (like the IMMR area on MPC8xx and 5804MPC826x processors), on others (parts of) the data cache can be 5805locked as (mis-) used as memory, etc. 5806 5807 Chris Hallinan posted a good summary of these issues to the 5808 U-Boot mailing list: 5809 5810 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5811 From: "Chris Hallinan" <clh@net1plus.com> 5812 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5813 ... 5814 5815 Correct me if I'm wrong, folks, but the way I understand it 5816 is this: Using DCACHE as initial RAM for Stack, etc, does not 5817 require any physical RAM backing up the cache. The cleverness 5818 is that the cache is being used as a temporary supply of 5819 necessary storage before the SDRAM controller is setup. It's 5820 beyond the scope of this list to explain the details, but you 5821 can see how this works by studying the cache architecture and 5822 operation in the architecture and processor-specific manuals. 5823 5824 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5825 is another option for the system designer to use as an 5826 initial stack/RAM area prior to SDRAM being available. Either 5827 option should work for you. Using CS 4 should be fine if your 5828 board designers haven't used it for something that would 5829 cause you grief during the initial boot! It is frequently not 5830 used. 5831 5832 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5833 with your processor/board/system design. The default value 5834 you will find in any recent u-boot distribution in 5835 walnut.h should work for you. I'd set it to a value larger 5836 than your SDRAM module. If you have a 64MB SDRAM module, set 5837 it above 400_0000. Just make sure your board has no resources 5838 that are supposed to respond to that address! That code in 5839 start.S has been around a while and should work as is when 5840 you get the config right. 5841 5842 -Chris Hallinan 5843 DS4.COM, Inc. 5844 5845It is essential to remember this, since it has some impact on the C 5846code for the initialization procedures: 5847 5848* Initialized global data (data segment) is read-only. Do not attempt 5849 to write it. 5850 5851* Do not use any uninitialized global data (or implicitely initialized 5852 as zero data - BSS segment) at all - this is undefined, initiali- 5853 zation is performed later (when relocating to RAM). 5854 5855* Stack space is very limited. Avoid big data buffers or things like 5856 that. 5857 5858Having only the stack as writable memory limits means we cannot use 5859normal global data to share information beween the code. But it 5860turned out that the implementation of U-Boot can be greatly 5861simplified by making a global data structure (gd_t) available to all 5862functions. We could pass a pointer to this data as argument to _all_ 5863functions, but this would bloat the code. Instead we use a feature of 5864the GCC compiler (Global Register Variables) to share the data: we 5865place a pointer (gd) to the global data into a register which we 5866reserve for this purpose. 5867 5868When choosing a register for such a purpose we are restricted by the 5869relevant (E)ABI specifications for the current architecture, and by 5870GCC's implementation. 5871 5872For PowerPC, the following registers have specific use: 5873 R1: stack pointer 5874 R2: reserved for system use 5875 R3-R4: parameter passing and return values 5876 R5-R10: parameter passing 5877 R13: small data area pointer 5878 R30: GOT pointer 5879 R31: frame pointer 5880 5881 (U-Boot also uses R12 as internal GOT pointer. r12 5882 is a volatile register so r12 needs to be reset when 5883 going back and forth between asm and C) 5884 5885 ==> U-Boot will use R2 to hold a pointer to the global data 5886 5887 Note: on PPC, we could use a static initializer (since the 5888 address of the global data structure is known at compile time), 5889 but it turned out that reserving a register results in somewhat 5890 smaller code - although the code savings are not that big (on 5891 average for all boards 752 bytes for the whole U-Boot image, 5892 624 text + 127 data). 5893 5894On Blackfin, the normal C ABI (except for P3) is followed as documented here: 5895 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 5896 5897 ==> U-Boot will use P3 to hold a pointer to the global data 5898 5899On ARM, the following registers are used: 5900 5901 R0: function argument word/integer result 5902 R1-R3: function argument word 5903 R9: platform specific 5904 R10: stack limit (used only if stack checking is enabled) 5905 R11: argument (frame) pointer 5906 R12: temporary workspace 5907 R13: stack pointer 5908 R14: link register 5909 R15: program counter 5910 5911 ==> U-Boot will use R9 to hold a pointer to the global data 5912 5913 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5914 5915On Nios II, the ABI is documented here: 5916 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5917 5918 ==> U-Boot will use gp to hold a pointer to the global data 5919 5920 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5921 to access small data sections, so gp is free. 5922 5923On NDS32, the following registers are used: 5924 5925 R0-R1: argument/return 5926 R2-R5: argument 5927 R15: temporary register for assembler 5928 R16: trampoline register 5929 R28: frame pointer (FP) 5930 R29: global pointer (GP) 5931 R30: link register (LP) 5932 R31: stack pointer (SP) 5933 PC: program counter (PC) 5934 5935 ==> U-Boot will use R10 to hold a pointer to the global data 5936 5937NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5938or current versions of GCC may "optimize" the code too much. 5939 5940Memory Management: 5941------------------ 5942 5943U-Boot runs in system state and uses physical addresses, i.e. the 5944MMU is not used either for address mapping nor for memory protection. 5945 5946The available memory is mapped to fixed addresses using the memory 5947controller. In this process, a contiguous block is formed for each 5948memory type (Flash, SDRAM, SRAM), even when it consists of several 5949physical memory banks. 5950 5951U-Boot is installed in the first 128 kB of the first Flash bank (on 5952TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5953booting and sizing and initializing DRAM, the code relocates itself 5954to the upper end of DRAM. Immediately below the U-Boot code some 5955memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5956configuration setting]. Below that, a structure with global Board 5957Info data is placed, followed by the stack (growing downward). 5958 5959Additionally, some exception handler code is copied to the low 8 kB 5960of DRAM (0x00000000 ... 0x00001FFF). 5961 5962So a typical memory configuration with 16 MB of DRAM could look like 5963this: 5964 5965 0x0000 0000 Exception Vector code 5966 : 5967 0x0000 1FFF 5968 0x0000 2000 Free for Application Use 5969 : 5970 : 5971 5972 : 5973 : 5974 0x00FB FF20 Monitor Stack (Growing downward) 5975 0x00FB FFAC Board Info Data and permanent copy of global data 5976 0x00FC 0000 Malloc Arena 5977 : 5978 0x00FD FFFF 5979 0x00FE 0000 RAM Copy of Monitor Code 5980 ... eventually: LCD or video framebuffer 5981 ... eventually: pRAM (Protected RAM - unchanged by reset) 5982 0x00FF FFFF [End of RAM] 5983 5984 5985System Initialization: 5986---------------------- 5987 5988In the reset configuration, U-Boot starts at the reset entry point 5989(on most PowerPC systems at address 0x00000100). Because of the reset 5990configuration for CS0# this is a mirror of the onboard Flash memory. 5991To be able to re-map memory U-Boot then jumps to its link address. 5992To be able to implement the initialization code in C, a (small!) 5993initial stack is set up in the internal Dual Ported RAM (in case CPUs 5994which provide such a feature like MPC8xx or MPC8260), or in a locked 5995part of the data cache. After that, U-Boot initializes the CPU core, 5996the caches and the SIU. 5997 5998Next, all (potentially) available memory banks are mapped using a 5999preliminary mapping. For example, we put them on 512 MB boundaries 6000(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6001on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6002programmed for SDRAM access. Using the temporary configuration, a 6003simple memory test is run that determines the size of the SDRAM 6004banks. 6005 6006When there is more than one SDRAM bank, and the banks are of 6007different size, the largest is mapped first. For equal size, the first 6008bank (CS2#) is mapped first. The first mapping is always for address 60090x00000000, with any additional banks following immediately to create 6010contiguous memory starting from 0. 6011 6012Then, the monitor installs itself at the upper end of the SDRAM area 6013and allocates memory for use by malloc() and for the global Board 6014Info data; also, the exception vector code is copied to the low RAM 6015pages, and the final stack is set up. 6016 6017Only after this relocation will you have a "normal" C environment; 6018until that you are restricted in several ways, mostly because you are 6019running from ROM, and because the code will have to be relocated to a 6020new address in RAM. 6021 6022 6023U-Boot Porting Guide: 6024---------------------- 6025 6026[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6027list, October 2002] 6028 6029 6030int main(int argc, char *argv[]) 6031{ 6032 sighandler_t no_more_time; 6033 6034 signal(SIGALRM, no_more_time); 6035 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6036 6037 if (available_money > available_manpower) { 6038 Pay consultant to port U-Boot; 6039 return 0; 6040 } 6041 6042 Download latest U-Boot source; 6043 6044 Subscribe to u-boot mailing list; 6045 6046 if (clueless) 6047 email("Hi, I am new to U-Boot, how do I get started?"); 6048 6049 while (learning) { 6050 Read the README file in the top level directory; 6051 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6052 Read applicable doc/*.README; 6053 Read the source, Luke; 6054 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6055 } 6056 6057 if (available_money > toLocalCurrency ($2500)) 6058 Buy a BDI3000; 6059 else 6060 Add a lot of aggravation and time; 6061 6062 if (a similar board exists) { /* hopefully... */ 6063 cp -a board/<similar> board/<myboard> 6064 cp include/configs/<similar>.h include/configs/<myboard>.h 6065 } else { 6066 Create your own board support subdirectory; 6067 Create your own board include/configs/<myboard>.h file; 6068 } 6069 Edit new board/<myboard> files 6070 Edit new include/configs/<myboard>.h 6071 6072 while (!accepted) { 6073 while (!running) { 6074 do { 6075 Add / modify source code; 6076 } until (compiles); 6077 Debug; 6078 if (clueless) 6079 email("Hi, I am having problems..."); 6080 } 6081 Send patch file to the U-Boot email list; 6082 if (reasonable critiques) 6083 Incorporate improvements from email list code review; 6084 else 6085 Defend code as written; 6086 } 6087 6088 return 0; 6089} 6090 6091void no_more_time (int sig) 6092{ 6093 hire_a_guru(); 6094} 6095 6096 6097Coding Standards: 6098----------------- 6099 6100All contributions to U-Boot should conform to the Linux kernel 6101coding style; see the file "Documentation/CodingStyle" and the script 6102"scripts/Lindent" in your Linux kernel source directory. 6103 6104Source files originating from a different project (for example the 6105MTD subsystem) are generally exempt from these guidelines and are not 6106reformated to ease subsequent migration to newer versions of those 6107sources. 6108 6109Please note that U-Boot is implemented in C (and to some small parts in 6110Assembler); no C++ is used, so please do not use C++ style comments (//) 6111in your code. 6112 6113Please also stick to the following formatting rules: 6114- remove any trailing white space 6115- use TAB characters for indentation and vertical alignment, not spaces 6116- make sure NOT to use DOS '\r\n' line feeds 6117- do not add more than 2 consecutive empty lines to source files 6118- do not add trailing empty lines to source files 6119 6120Submissions which do not conform to the standards may be returned 6121with a request to reformat the changes. 6122 6123 6124Submitting Patches: 6125------------------- 6126 6127Since the number of patches for U-Boot is growing, we need to 6128establish some rules. Submissions which do not conform to these rules 6129may be rejected, even when they contain important and valuable stuff. 6130 6131Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6132 6133Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6134see http://lists.denx.de/mailman/listinfo/u-boot 6135 6136When you send a patch, please include the following information with 6137it: 6138 6139* For bug fixes: a description of the bug and how your patch fixes 6140 this bug. Please try to include a way of demonstrating that the 6141 patch actually fixes something. 6142 6143* For new features: a description of the feature and your 6144 implementation. 6145 6146* A CHANGELOG entry as plaintext (separate from the patch) 6147 6148* For major contributions, your entry to the CREDITS file 6149 6150* When you add support for a new board, don't forget to add a 6151 maintainer e-mail address to the boards.cfg file, too. 6152 6153* If your patch adds new configuration options, don't forget to 6154 document these in the README file. 6155 6156* The patch itself. If you are using git (which is *strongly* 6157 recommended) you can easily generate the patch using the 6158 "git format-patch". If you then use "git send-email" to send it to 6159 the U-Boot mailing list, you will avoid most of the common problems 6160 with some other mail clients. 6161 6162 If you cannot use git, use "diff -purN OLD NEW". If your version of 6163 diff does not support these options, then get the latest version of 6164 GNU diff. 6165 6166 The current directory when running this command shall be the parent 6167 directory of the U-Boot source tree (i. e. please make sure that 6168 your patch includes sufficient directory information for the 6169 affected files). 6170 6171 We prefer patches as plain text. MIME attachments are discouraged, 6172 and compressed attachments must not be used. 6173 6174* If one logical set of modifications affects or creates several 6175 files, all these changes shall be submitted in a SINGLE patch file. 6176 6177* Changesets that contain different, unrelated modifications shall be 6178 submitted as SEPARATE patches, one patch per changeset. 6179 6180 6181Notes: 6182 6183* Before sending the patch, run the MAKEALL script on your patched 6184 source tree and make sure that no errors or warnings are reported 6185 for any of the boards. 6186 6187* Keep your modifications to the necessary minimum: A patch 6188 containing several unrelated changes or arbitrary reformats will be 6189 returned with a request to re-formatting / split it. 6190 6191* If you modify existing code, make sure that your new code does not 6192 add to the memory footprint of the code ;-) Small is beautiful! 6193 When adding new features, these should compile conditionally only 6194 (using #ifdef), and the resulting code with the new feature 6195 disabled must not need more memory than the old code without your 6196 modification. 6197 6198* Remember that there is a size limit of 100 kB per message on the 6199 u-boot mailing list. Bigger patches will be moderated. If they are 6200 reasonable and not too big, they will be acknowledged. But patches 6201 bigger than the size limit should be avoided. 6202