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- USB Device Firmware Update (DFU) class support: 1538 CONFIG_DFU_FUNCTION 1539 This enables the USB portion of the DFU USB class 1540 1541 CONFIG_CMD_DFU 1542 This enables the command "dfu" which is used to have 1543 U-Boot create a DFU class device via USB. This command 1544 requires that the "dfu_alt_info" environment variable be 1545 set and define the alt settings to expose to the host. 1546 1547 CONFIG_DFU_MMC 1548 This enables support for exposing (e)MMC devices via DFU. 1549 1550 CONFIG_DFU_NAND 1551 This enables support for exposing NAND devices via DFU. 1552 1553 CONFIG_DFU_RAM 1554 This enables support for exposing RAM via DFU. 1555 Note: DFU spec refer to non-volatile memory usage, but 1556 allow usages beyond the scope of spec - here RAM usage, 1557 one that would help mostly the developer. 1558 1559 CONFIG_SYS_DFU_DATA_BUF_SIZE 1560 Dfu transfer uses a buffer before writing data to the 1561 raw storage device. Make the size (in bytes) of this buffer 1562 configurable. The size of this buffer is also configurable 1563 through the "dfu_bufsiz" environment variable. 1564 1565 CONFIG_SYS_DFU_MAX_FILE_SIZE 1566 When updating files rather than the raw storage device, 1567 we use a static buffer to copy the file into and then write 1568 the buffer once we've been given the whole file. Define 1569 this to the maximum filesize (in bytes) for the buffer. 1570 Default is 4 MiB if undefined. 1571 1572 DFU_DEFAULT_POLL_TIMEOUT 1573 Poll timeout [ms], is the timeout a device can send to the 1574 host. The host must wait for this timeout before sending 1575 a subsequent DFU_GET_STATUS request to the device. 1576 1577 DFU_MANIFEST_POLL_TIMEOUT 1578 Poll timeout [ms], which the device sends to the host when 1579 entering dfuMANIFEST state. Host waits this timeout, before 1580 sending again an USB request to the device. 1581 1582- Journaling Flash filesystem support: 1583 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1584 CONFIG_JFFS2_NAND_DEV 1585 Define these for a default partition on a NAND device 1586 1587 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1588 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1589 Define these for a default partition on a NOR device 1590 1591 CONFIG_SYS_JFFS_CUSTOM_PART 1592 Define this to create an own partition. You have to provide a 1593 function struct part_info* jffs2_part_info(int part_num) 1594 1595 If you define only one JFFS2 partition you may also want to 1596 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1597 to disable the command chpart. This is the default when you 1598 have not defined a custom partition 1599 1600- FAT(File Allocation Table) filesystem write function support: 1601 CONFIG_FAT_WRITE 1602 1603 Define this to enable support for saving memory data as a 1604 file in FAT formatted partition. 1605 1606 This will also enable the command "fatwrite" enabling the 1607 user to write files to FAT. 1608 1609CBFS (Coreboot Filesystem) support 1610 CONFIG_CMD_CBFS 1611 1612 Define this to enable support for reading from a Coreboot 1613 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1614 and cbfsload. 1615 1616- Keyboard Support: 1617 CONFIG_ISA_KEYBOARD 1618 1619 Define this to enable standard (PC-Style) keyboard 1620 support 1621 1622 CONFIG_I8042_KBD 1623 Standard PC keyboard driver with US (is default) and 1624 GERMAN key layout (switch via environment 'keymap=de') support. 1625 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1626 for cfb_console. Supports cursor blinking. 1627 1628 CONFIG_CROS_EC_KEYB 1629 Enables a Chrome OS keyboard using the CROS_EC interface. 1630 This uses CROS_EC to communicate with a second microcontroller 1631 which provides key scans on request. 1632 1633- Video support: 1634 CONFIG_VIDEO 1635 1636 Define this to enable video support (for output to 1637 video). 1638 1639 CONFIG_VIDEO_CT69000 1640 1641 Enable Chips & Technologies 69000 Video chip 1642 1643 CONFIG_VIDEO_SMI_LYNXEM 1644 Enable Silicon Motion SMI 712/710/810 Video chip. The 1645 video output is selected via environment 'videoout' 1646 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1647 assumed. 1648 1649 For the CT69000 and SMI_LYNXEM drivers, videomode is 1650 selected via environment 'videomode'. Two different ways 1651 are possible: 1652 - "videomode=num" 'num' is a standard LiLo mode numbers. 1653 Following standard modes are supported (* is default): 1654 1655 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1656 -------------+--------------------------------------------- 1657 8 bits | 0x301* 0x303 0x305 0x161 0x307 1658 15 bits | 0x310 0x313 0x316 0x162 0x319 1659 16 bits | 0x311 0x314 0x317 0x163 0x31A 1660 24 bits | 0x312 0x315 0x318 ? 0x31B 1661 -------------+--------------------------------------------- 1662 (i.e. setenv videomode 317; saveenv; reset;) 1663 1664 - "videomode=bootargs" all the video parameters are parsed 1665 from the bootargs. (See drivers/video/videomodes.c) 1666 1667 1668 CONFIG_VIDEO_SED13806 1669 Enable Epson SED13806 driver. This driver supports 8bpp 1670 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1671 or CONFIG_VIDEO_SED13806_16BPP 1672 1673 CONFIG_FSL_DIU_FB 1674 Enable the Freescale DIU video driver. Reference boards for 1675 SOCs that have a DIU should define this macro to enable DIU 1676 support, and should also define these other macros: 1677 1678 CONFIG_SYS_DIU_ADDR 1679 CONFIG_VIDEO 1680 CONFIG_CMD_BMP 1681 CONFIG_CFB_CONSOLE 1682 CONFIG_VIDEO_SW_CURSOR 1683 CONFIG_VGA_AS_SINGLE_DEVICE 1684 CONFIG_VIDEO_LOGO 1685 CONFIG_VIDEO_BMP_LOGO 1686 1687 The DIU driver will look for the 'video-mode' environment 1688 variable, and if defined, enable the DIU as a console during 1689 boot. See the documentation file README.video for a 1690 description of this variable. 1691 1692 CONFIG_VIDEO_VGA 1693 1694 Enable the VGA video / BIOS for x86. The alternative if you 1695 are using coreboot is to use the coreboot frame buffer 1696 driver. 1697 1698 1699- Keyboard Support: 1700 CONFIG_KEYBOARD 1701 1702 Define this to enable a custom keyboard support. 1703 This simply calls drv_keyboard_init() which must be 1704 defined in your board-specific files. 1705 The only board using this so far is RBC823. 1706 1707- LCD Support: CONFIG_LCD 1708 1709 Define this to enable LCD support (for output to LCD 1710 display); also select one of the supported displays 1711 by defining one of these: 1712 1713 CONFIG_ATMEL_LCD: 1714 1715 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1716 1717 CONFIG_NEC_NL6448AC33: 1718 1719 NEC NL6448AC33-18. Active, color, single scan. 1720 1721 CONFIG_NEC_NL6448BC20 1722 1723 NEC NL6448BC20-08. 6.5", 640x480. 1724 Active, color, single scan. 1725 1726 CONFIG_NEC_NL6448BC33_54 1727 1728 NEC NL6448BC33-54. 10.4", 640x480. 1729 Active, color, single scan. 1730 1731 CONFIG_SHARP_16x9 1732 1733 Sharp 320x240. Active, color, single scan. 1734 It isn't 16x9, and I am not sure what it is. 1735 1736 CONFIG_SHARP_LQ64D341 1737 1738 Sharp LQ64D341 display, 640x480. 1739 Active, color, single scan. 1740 1741 CONFIG_HLD1045 1742 1743 HLD1045 display, 640x480. 1744 Active, color, single scan. 1745 1746 CONFIG_OPTREX_BW 1747 1748 Optrex CBL50840-2 NF-FW 99 22 M5 1749 or 1750 Hitachi LMG6912RPFC-00T 1751 or 1752 Hitachi SP14Q002 1753 1754 320x240. Black & white. 1755 1756 Normally display is black on white background; define 1757 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1758 1759 CONFIG_LCD_ALIGNMENT 1760 1761 Normally the LCD is page-aligned (tyically 4KB). If this is 1762 defined then the LCD will be aligned to this value instead. 1763 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1764 here, since it is cheaper to change data cache settings on 1765 a per-section basis. 1766 1767 CONFIG_CONSOLE_SCROLL_LINES 1768 1769 When the console need to be scrolled, this is the number of 1770 lines to scroll by. It defaults to 1. Increasing this makes 1771 the console jump but can help speed up operation when scrolling 1772 is slow. 1773 1774 CONFIG_LCD_BMP_RLE8 1775 1776 Support drawing of RLE8-compressed bitmaps on the LCD. 1777 1778 CONFIG_I2C_EDID 1779 1780 Enables an 'i2c edid' command which can read EDID 1781 information over I2C from an attached LCD display. 1782 1783- Splash Screen Support: CONFIG_SPLASH_SCREEN 1784 1785 If this option is set, the environment is checked for 1786 a variable "splashimage". If found, the usual display 1787 of logo, copyright and system information on the LCD 1788 is suppressed and the BMP image at the address 1789 specified in "splashimage" is loaded instead. The 1790 console is redirected to the "nulldev", too. This 1791 allows for a "silent" boot where a splash screen is 1792 loaded very quickly after power-on. 1793 1794 CONFIG_SPLASHIMAGE_GUARD 1795 1796 If this option is set, then U-Boot will prevent the environment 1797 variable "splashimage" from being set to a problematic address 1798 (see README.displaying-bmps). 1799 This option is useful for targets where, due to alignment 1800 restrictions, an improperly aligned BMP image will cause a data 1801 abort. If you think you will not have problems with unaligned 1802 accesses (for example because your toolchain prevents them) 1803 there is no need to set this option. 1804 1805 CONFIG_SPLASH_SCREEN_ALIGN 1806 1807 If this option is set the splash image can be freely positioned 1808 on the screen. Environment variable "splashpos" specifies the 1809 position as "x,y". If a positive number is given it is used as 1810 number of pixel from left/top. If a negative number is given it 1811 is used as number of pixel from right/bottom. You can also 1812 specify 'm' for centering the image. 1813 1814 Example: 1815 setenv splashpos m,m 1816 => image at center of screen 1817 1818 setenv splashpos 30,20 1819 => image at x = 30 and y = 20 1820 1821 setenv splashpos -10,m 1822 => vertically centered image 1823 at x = dspWidth - bmpWidth - 9 1824 1825- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1826 1827 If this option is set, additionally to standard BMP 1828 images, gzipped BMP images can be displayed via the 1829 splashscreen support or the bmp command. 1830 1831- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1832 1833 If this option is set, 8-bit RLE compressed BMP images 1834 can be displayed via the splashscreen support or the 1835 bmp command. 1836 1837- Do compresssing for memory range: 1838 CONFIG_CMD_ZIP 1839 1840 If this option is set, it would use zlib deflate method 1841 to compress the specified memory at its best effort. 1842 1843- Compression support: 1844 CONFIG_GZIP 1845 1846 Enabled by default to support gzip compressed images. 1847 1848 CONFIG_BZIP2 1849 1850 If this option is set, support for bzip2 compressed 1851 images is included. If not, only uncompressed and gzip 1852 compressed images are supported. 1853 1854 NOTE: the bzip2 algorithm requires a lot of RAM, so 1855 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1856 be at least 4MB. 1857 1858 CONFIG_LZMA 1859 1860 If this option is set, support for lzma compressed 1861 images is included. 1862 1863 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1864 requires an amount of dynamic memory that is given by the 1865 formula: 1866 1867 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1868 1869 Where lc and lp stand for, respectively, Literal context bits 1870 and Literal pos bits. 1871 1872 This value is upper-bounded by 14MB in the worst case. Anyway, 1873 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1874 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1875 a very small buffer. 1876 1877 Use the lzmainfo tool to determinate the lc and lp values and 1878 then calculate the amount of needed dynamic memory (ensuring 1879 the appropriate CONFIG_SYS_MALLOC_LEN value). 1880 1881 CONFIG_LZO 1882 1883 If this option is set, support for LZO compressed images 1884 is included. 1885 1886- MII/PHY support: 1887 CONFIG_PHY_ADDR 1888 1889 The address of PHY on MII bus. 1890 1891 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1892 1893 The clock frequency of the MII bus 1894 1895 CONFIG_PHY_GIGE 1896 1897 If this option is set, support for speed/duplex 1898 detection of gigabit PHY is included. 1899 1900 CONFIG_PHY_RESET_DELAY 1901 1902 Some PHY like Intel LXT971A need extra delay after 1903 reset before any MII register access is possible. 1904 For such PHY, set this option to the usec delay 1905 required. (minimum 300usec for LXT971A) 1906 1907 CONFIG_PHY_CMD_DELAY (ppc4xx) 1908 1909 Some PHY like Intel LXT971A need extra delay after 1910 command issued before MII status register can be read 1911 1912- Ethernet address: 1913 CONFIG_ETHADDR 1914 CONFIG_ETH1ADDR 1915 CONFIG_ETH2ADDR 1916 CONFIG_ETH3ADDR 1917 CONFIG_ETH4ADDR 1918 CONFIG_ETH5ADDR 1919 1920 Define a default value for Ethernet address to use 1921 for the respective Ethernet interface, in case this 1922 is not determined automatically. 1923 1924- IP address: 1925 CONFIG_IPADDR 1926 1927 Define a default value for the IP address to use for 1928 the default Ethernet interface, in case this is not 1929 determined through e.g. bootp. 1930 (Environment variable "ipaddr") 1931 1932- Server IP address: 1933 CONFIG_SERVERIP 1934 1935 Defines a default value for the IP address of a TFTP 1936 server to contact when using the "tftboot" command. 1937 (Environment variable "serverip") 1938 1939 CONFIG_KEEP_SERVERADDR 1940 1941 Keeps the server's MAC address, in the env 'serveraddr' 1942 for passing to bootargs (like Linux's netconsole option) 1943 1944- Gateway IP address: 1945 CONFIG_GATEWAYIP 1946 1947 Defines a default value for the IP address of the 1948 default router where packets to other networks are 1949 sent to. 1950 (Environment variable "gatewayip") 1951 1952- Subnet mask: 1953 CONFIG_NETMASK 1954 1955 Defines a default value for the subnet mask (or 1956 routing prefix) which is used to determine if an IP 1957 address belongs to the local subnet or needs to be 1958 forwarded through a router. 1959 (Environment variable "netmask") 1960 1961- Multicast TFTP Mode: 1962 CONFIG_MCAST_TFTP 1963 1964 Defines whether you want to support multicast TFTP as per 1965 rfc-2090; for example to work with atftp. Lets lots of targets 1966 tftp down the same boot image concurrently. Note: the Ethernet 1967 driver in use must provide a function: mcast() to join/leave a 1968 multicast group. 1969 1970- BOOTP Recovery Mode: 1971 CONFIG_BOOTP_RANDOM_DELAY 1972 1973 If you have many targets in a network that try to 1974 boot using BOOTP, you may want to avoid that all 1975 systems send out BOOTP requests at precisely the same 1976 moment (which would happen for instance at recovery 1977 from a power failure, when all systems will try to 1978 boot, thus flooding the BOOTP server. Defining 1979 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1980 inserted before sending out BOOTP requests. The 1981 following delays are inserted then: 1982 1983 1st BOOTP request: delay 0 ... 1 sec 1984 2nd BOOTP request: delay 0 ... 2 sec 1985 3rd BOOTP request: delay 0 ... 4 sec 1986 4th and following 1987 BOOTP requests: delay 0 ... 8 sec 1988 1989- DHCP Advanced Options: 1990 You can fine tune the DHCP functionality by defining 1991 CONFIG_BOOTP_* symbols: 1992 1993 CONFIG_BOOTP_SUBNETMASK 1994 CONFIG_BOOTP_GATEWAY 1995 CONFIG_BOOTP_HOSTNAME 1996 CONFIG_BOOTP_NISDOMAIN 1997 CONFIG_BOOTP_BOOTPATH 1998 CONFIG_BOOTP_BOOTFILESIZE 1999 CONFIG_BOOTP_DNS 2000 CONFIG_BOOTP_DNS2 2001 CONFIG_BOOTP_SEND_HOSTNAME 2002 CONFIG_BOOTP_NTPSERVER 2003 CONFIG_BOOTP_TIMEOFFSET 2004 CONFIG_BOOTP_VENDOREX 2005 CONFIG_BOOTP_MAY_FAIL 2006 2007 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2008 environment variable, not the BOOTP server. 2009 2010 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2011 after the configured retry count, the call will fail 2012 instead of starting over. This can be used to fail over 2013 to Link-local IP address configuration if the DHCP server 2014 is not available. 2015 2016 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2017 serverip from a DHCP server, it is possible that more 2018 than one DNS serverip is offered to the client. 2019 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2020 serverip will be stored in the additional environment 2021 variable "dnsip2". The first DNS serverip is always 2022 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2023 is defined. 2024 2025 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2026 to do a dynamic update of a DNS server. To do this, they 2027 need the hostname of the DHCP requester. 2028 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2029 of the "hostname" environment variable is passed as 2030 option 12 to the DHCP server. 2031 2032 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2033 2034 A 32bit value in microseconds for a delay between 2035 receiving a "DHCP Offer" and sending the "DHCP Request". 2036 This fixes a problem with certain DHCP servers that don't 2037 respond 100% of the time to a "DHCP request". E.g. On an 2038 AT91RM9200 processor running at 180MHz, this delay needed 2039 to be *at least* 15,000 usec before a Windows Server 2003 2040 DHCP server would reply 100% of the time. I recommend at 2041 least 50,000 usec to be safe. The alternative is to hope 2042 that one of the retries will be successful but note that 2043 the DHCP timeout and retry process takes a longer than 2044 this delay. 2045 2046 - Link-local IP address negotiation: 2047 Negotiate with other link-local clients on the local network 2048 for an address that doesn't require explicit configuration. 2049 This is especially useful if a DHCP server cannot be guaranteed 2050 to exist in all environments that the device must operate. 2051 2052 See doc/README.link-local for more information. 2053 2054 - CDP Options: 2055 CONFIG_CDP_DEVICE_ID 2056 2057 The device id used in CDP trigger frames. 2058 2059 CONFIG_CDP_DEVICE_ID_PREFIX 2060 2061 A two character string which is prefixed to the MAC address 2062 of the device. 2063 2064 CONFIG_CDP_PORT_ID 2065 2066 A printf format string which contains the ascii name of 2067 the port. Normally is set to "eth%d" which sets 2068 eth0 for the first Ethernet, eth1 for the second etc. 2069 2070 CONFIG_CDP_CAPABILITIES 2071 2072 A 32bit integer which indicates the device capabilities; 2073 0x00000010 for a normal host which does not forwards. 2074 2075 CONFIG_CDP_VERSION 2076 2077 An ascii string containing the version of the software. 2078 2079 CONFIG_CDP_PLATFORM 2080 2081 An ascii string containing the name of the platform. 2082 2083 CONFIG_CDP_TRIGGER 2084 2085 A 32bit integer sent on the trigger. 2086 2087 CONFIG_CDP_POWER_CONSUMPTION 2088 2089 A 16bit integer containing the power consumption of the 2090 device in .1 of milliwatts. 2091 2092 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2093 2094 A byte containing the id of the VLAN. 2095 2096- Status LED: CONFIG_STATUS_LED 2097 2098 Several configurations allow to display the current 2099 status using a LED. For instance, the LED will blink 2100 fast while running U-Boot code, stop blinking as 2101 soon as a reply to a BOOTP request was received, and 2102 start blinking slow once the Linux kernel is running 2103 (supported by a status LED driver in the Linux 2104 kernel). Defining CONFIG_STATUS_LED enables this 2105 feature in U-Boot. 2106 2107 Additional options: 2108 2109 CONFIG_GPIO_LED 2110 The status LED can be connected to a GPIO pin. 2111 In such cases, the gpio_led driver can be used as a 2112 status LED backend implementation. Define CONFIG_GPIO_LED 2113 to include the gpio_led driver in the U-Boot binary. 2114 2115 CONFIG_GPIO_LED_INVERTED_TABLE 2116 Some GPIO connected LEDs may have inverted polarity in which 2117 case the GPIO high value corresponds to LED off state and 2118 GPIO low value corresponds to LED on state. 2119 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2120 with a list of GPIO LEDs that have inverted polarity. 2121 2122- CAN Support: CONFIG_CAN_DRIVER 2123 2124 Defining CONFIG_CAN_DRIVER enables CAN driver support 2125 on those systems that support this (optional) 2126 feature, like the TQM8xxL modules. 2127 2128- I2C Support: CONFIG_SYS_I2C 2129 2130 This enable the NEW i2c subsystem, and will allow you to use 2131 i2c commands at the u-boot command line (as long as you set 2132 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2133 based realtime clock chips or other i2c devices. See 2134 common/cmd_i2c.c for a description of the command line 2135 interface. 2136 2137 ported i2c driver to the new framework: 2138 - drivers/i2c/soft_i2c.c: 2139 - activate first bus with CONFIG_SYS_I2C_SOFT define 2140 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2141 for defining speed and slave address 2142 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2143 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2144 for defining speed and slave address 2145 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2146 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2147 for defining speed and slave address 2148 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2149 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2150 for defining speed and slave address 2151 2152 - drivers/i2c/fsl_i2c.c: 2153 - activate i2c driver with CONFIG_SYS_I2C_FSL 2154 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2155 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2156 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2157 bus. 2158 - If your board supports a second fsl i2c bus, define 2159 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2160 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2161 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2162 second bus. 2163 2164 - drivers/i2c/tegra_i2c.c: 2165 - activate this driver with CONFIG_SYS_I2C_TEGRA 2166 - This driver adds 4 i2c buses with a fix speed from 2167 100000 and the slave addr 0! 2168 2169 - drivers/i2c/ppc4xx_i2c.c 2170 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2171 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2172 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2173 2174 - drivers/i2c/i2c_mxc.c 2175 - activate this driver with CONFIG_SYS_I2C_MXC 2176 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2177 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2178 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2179 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2180 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2181 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2182 If thoses defines are not set, default value is 100000 2183 for speed, and 0 for slave. 2184 2185 - drivers/i2c/rcar_i2c.c: 2186 - activate this driver with CONFIG_SYS_I2C_RCAR 2187 - This driver adds 4 i2c buses 2188 2189 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2190 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2191 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2192 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2193 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2194 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2195 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2196 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2197 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2198 2199 - drivers/i2c/sh_i2c.c: 2200 - activate this driver with CONFIG_SYS_I2C_SH 2201 - This driver adds from 2 to 5 i2c buses 2202 2203 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2204 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2205 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2206 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2207 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2208 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2209 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2210 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2211 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2212 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2213 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2214 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2215 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses 2216 2217 - drivers/i2c/omap24xx_i2c.c 2218 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2219 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2220 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2221 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2222 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2223 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2224 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2225 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2226 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2227 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2228 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2229 2230 - drivers/i2c/zynq_i2c.c 2231 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2232 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2233 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2234 2235 - drivers/i2c/s3c24x0_i2c.c: 2236 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2237 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2238 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2239 with a fix speed from 100000 and the slave addr 0! 2240 2241 additional defines: 2242 2243 CONFIG_SYS_NUM_I2C_BUSES 2244 Hold the number of i2c busses you want to use. If you 2245 don't use/have i2c muxes on your i2c bus, this 2246 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2247 omit this define. 2248 2249 CONFIG_SYS_I2C_DIRECT_BUS 2250 define this, if you don't use i2c muxes on your hardware. 2251 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2252 omit this define. 2253 2254 CONFIG_SYS_I2C_MAX_HOPS 2255 define how many muxes are maximal consecutively connected 2256 on one i2c bus. If you not use i2c muxes, omit this 2257 define. 2258 2259 CONFIG_SYS_I2C_BUSES 2260 hold a list of busses you want to use, only used if 2261 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2262 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2263 CONFIG_SYS_NUM_I2C_BUSES = 9: 2264 2265 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2266 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2267 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2268 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2269 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2270 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2271 {1, {I2C_NULL_HOP}}, \ 2272 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2273 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2274 } 2275 2276 which defines 2277 bus 0 on adapter 0 without a mux 2278 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2279 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2280 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2281 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2282 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2283 bus 6 on adapter 1 without a mux 2284 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2285 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2286 2287 If you do not have i2c muxes on your board, omit this define. 2288 2289- Legacy I2C Support: CONFIG_HARD_I2C 2290 2291 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2292 provides the following compelling advantages: 2293 2294 - more than one i2c adapter is usable 2295 - approved multibus support 2296 - better i2c mux support 2297 2298 ** Please consider updating your I2C driver now. ** 2299 2300 These enable legacy I2C serial bus commands. Defining 2301 CONFIG_HARD_I2C will include the appropriate I2C driver 2302 for the selected CPU. 2303 2304 This will allow you to use i2c commands at the u-boot 2305 command line (as long as you set CONFIG_CMD_I2C in 2306 CONFIG_COMMANDS) and communicate with i2c based realtime 2307 clock chips. See common/cmd_i2c.c for a description of the 2308 command line interface. 2309 2310 CONFIG_HARD_I2C selects a hardware I2C controller. 2311 2312 There are several other quantities that must also be 2313 defined when you define CONFIG_HARD_I2C. 2314 2315 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2316 to be the frequency (in Hz) at which you wish your i2c bus 2317 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2318 the CPU's i2c node address). 2319 2320 Now, the u-boot i2c code for the mpc8xx 2321 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2322 and so its address should therefore be cleared to 0 (See, 2323 eg, MPC823e User's Manual p.16-473). So, set 2324 CONFIG_SYS_I2C_SLAVE to 0. 2325 2326 CONFIG_SYS_I2C_INIT_MPC5XXX 2327 2328 When a board is reset during an i2c bus transfer 2329 chips might think that the current transfer is still 2330 in progress. Reset the slave devices by sending start 2331 commands until the slave device responds. 2332 2333 That's all that's required for CONFIG_HARD_I2C. 2334 2335 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2336 then the following macros need to be defined (examples are 2337 from include/configs/lwmon.h): 2338 2339 I2C_INIT 2340 2341 (Optional). Any commands necessary to enable the I2C 2342 controller or configure ports. 2343 2344 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2345 2346 I2C_PORT 2347 2348 (Only for MPC8260 CPU). The I/O port to use (the code 2349 assumes both bits are on the same port). Valid values 2350 are 0..3 for ports A..D. 2351 2352 I2C_ACTIVE 2353 2354 The code necessary to make the I2C data line active 2355 (driven). If the data line is open collector, this 2356 define can be null. 2357 2358 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2359 2360 I2C_TRISTATE 2361 2362 The code necessary to make the I2C data line tri-stated 2363 (inactive). If the data line is open collector, this 2364 define can be null. 2365 2366 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2367 2368 I2C_READ 2369 2370 Code that returns true if the I2C data line is high, 2371 false if it is low. 2372 2373 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2374 2375 I2C_SDA(bit) 2376 2377 If <bit> is true, sets the I2C data line high. If it 2378 is false, it clears it (low). 2379 2380 eg: #define I2C_SDA(bit) \ 2381 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2382 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2383 2384 I2C_SCL(bit) 2385 2386 If <bit> is true, sets the I2C clock line high. If it 2387 is false, it clears it (low). 2388 2389 eg: #define I2C_SCL(bit) \ 2390 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2391 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2392 2393 I2C_DELAY 2394 2395 This delay is invoked four times per clock cycle so this 2396 controls the rate of data transfer. The data rate thus 2397 is 1 / (I2C_DELAY * 4). Often defined to be something 2398 like: 2399 2400 #define I2C_DELAY udelay(2) 2401 2402 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2403 2404 If your arch supports the generic GPIO framework (asm/gpio.h), 2405 then you may alternatively define the two GPIOs that are to be 2406 used as SCL / SDA. Any of the previous I2C_xxx macros will 2407 have GPIO-based defaults assigned to them as appropriate. 2408 2409 You should define these to the GPIO value as given directly to 2410 the generic GPIO functions. 2411 2412 CONFIG_SYS_I2C_INIT_BOARD 2413 2414 When a board is reset during an i2c bus transfer 2415 chips might think that the current transfer is still 2416 in progress. On some boards it is possible to access 2417 the i2c SCLK line directly, either by using the 2418 processor pin as a GPIO or by having a second pin 2419 connected to the bus. If this option is defined a 2420 custom i2c_init_board() routine in boards/xxx/board.c 2421 is run early in the boot sequence. 2422 2423 CONFIG_SYS_I2C_BOARD_LATE_INIT 2424 2425 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2426 defined a custom i2c_board_late_init() routine in 2427 boards/xxx/board.c is run AFTER the operations in i2c_init() 2428 is completed. This callpoint can be used to unreset i2c bus 2429 using CPU i2c controller register accesses for CPUs whose i2c 2430 controller provide such a method. It is called at the end of 2431 i2c_init() to allow i2c_init operations to setup the i2c bus 2432 controller on the CPU (e.g. setting bus speed & slave address). 2433 2434 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2435 2436 This option enables configuration of bi_iic_fast[] flags 2437 in u-boot bd_info structure based on u-boot environment 2438 variable "i2cfast". (see also i2cfast) 2439 2440 CONFIG_I2C_MULTI_BUS 2441 2442 This option allows the use of multiple I2C buses, each of which 2443 must have a controller. At any point in time, only one bus is 2444 active. To switch to a different bus, use the 'i2c dev' command. 2445 Note that bus numbering is zero-based. 2446 2447 CONFIG_SYS_I2C_NOPROBES 2448 2449 This option specifies a list of I2C devices that will be skipped 2450 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2451 is set, specify a list of bus-device pairs. Otherwise, specify 2452 a 1D array of device addresses 2453 2454 e.g. 2455 #undef CONFIG_I2C_MULTI_BUS 2456 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2457 2458 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2459 2460 #define CONFIG_I2C_MULTI_BUS 2461 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2462 2463 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2464 2465 CONFIG_SYS_SPD_BUS_NUM 2466 2467 If defined, then this indicates the I2C bus number for DDR SPD. 2468 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2469 2470 CONFIG_SYS_RTC_BUS_NUM 2471 2472 If defined, then this indicates the I2C bus number for the RTC. 2473 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2474 2475 CONFIG_SYS_DTT_BUS_NUM 2476 2477 If defined, then this indicates the I2C bus number for the DTT. 2478 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2479 2480 CONFIG_SYS_I2C_DTT_ADDR: 2481 2482 If defined, specifies the I2C address of the DTT device. 2483 If not defined, then U-Boot uses predefined value for 2484 specified DTT device. 2485 2486 CONFIG_SOFT_I2C_READ_REPEATED_START 2487 2488 defining this will force the i2c_read() function in 2489 the soft_i2c driver to perform an I2C repeated start 2490 between writing the address pointer and reading the 2491 data. If this define is omitted the default behaviour 2492 of doing a stop-start sequence will be used. Most I2C 2493 devices can use either method, but some require one or 2494 the other. 2495 2496- SPI Support: CONFIG_SPI 2497 2498 Enables SPI driver (so far only tested with 2499 SPI EEPROM, also an instance works with Crystal A/D and 2500 D/As on the SACSng board) 2501 2502 CONFIG_SH_SPI 2503 2504 Enables the driver for SPI controller on SuperH. Currently 2505 only SH7757 is supported. 2506 2507 CONFIG_SPI_X 2508 2509 Enables extended (16-bit) SPI EEPROM addressing. 2510 (symmetrical to CONFIG_I2C_X) 2511 2512 CONFIG_SOFT_SPI 2513 2514 Enables a software (bit-bang) SPI driver rather than 2515 using hardware support. This is a general purpose 2516 driver that only requires three general I/O port pins 2517 (two outputs, one input) to function. If this is 2518 defined, the board configuration must define several 2519 SPI configuration items (port pins to use, etc). For 2520 an example, see include/configs/sacsng.h. 2521 2522 CONFIG_HARD_SPI 2523 2524 Enables a hardware SPI driver for general-purpose reads 2525 and writes. As with CONFIG_SOFT_SPI, the board configuration 2526 must define a list of chip-select function pointers. 2527 Currently supported on some MPC8xxx processors. For an 2528 example, see include/configs/mpc8349emds.h. 2529 2530 CONFIG_MXC_SPI 2531 2532 Enables the driver for the SPI controllers on i.MX and MXC 2533 SoCs. Currently i.MX31/35/51 are supported. 2534 2535- FPGA Support: CONFIG_FPGA 2536 2537 Enables FPGA subsystem. 2538 2539 CONFIG_FPGA_<vendor> 2540 2541 Enables support for specific chip vendors. 2542 (ALTERA, XILINX) 2543 2544 CONFIG_FPGA_<family> 2545 2546 Enables support for FPGA family. 2547 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2548 2549 CONFIG_FPGA_COUNT 2550 2551 Specify the number of FPGA devices to support. 2552 2553 CONFIG_CMD_FPGA_LOADMK 2554 2555 Enable support for fpga loadmk command 2556 2557 CONFIG_CMD_FPGA_LOADP 2558 2559 Enable support for fpga loadp command - load partial bitstream 2560 2561 CONFIG_CMD_FPGA_LOADBP 2562 2563 Enable support for fpga loadbp command - load partial bitstream 2564 (Xilinx only) 2565 2566 CONFIG_SYS_FPGA_PROG_FEEDBACK 2567 2568 Enable printing of hash marks during FPGA configuration. 2569 2570 CONFIG_SYS_FPGA_CHECK_BUSY 2571 2572 Enable checks on FPGA configuration interface busy 2573 status by the configuration function. This option 2574 will require a board or device specific function to 2575 be written. 2576 2577 CONFIG_FPGA_DELAY 2578 2579 If defined, a function that provides delays in the FPGA 2580 configuration driver. 2581 2582 CONFIG_SYS_FPGA_CHECK_CTRLC 2583 Allow Control-C to interrupt FPGA configuration 2584 2585 CONFIG_SYS_FPGA_CHECK_ERROR 2586 2587 Check for configuration errors during FPGA bitfile 2588 loading. For example, abort during Virtex II 2589 configuration if the INIT_B line goes low (which 2590 indicated a CRC error). 2591 2592 CONFIG_SYS_FPGA_WAIT_INIT 2593 2594 Maximum time to wait for the INIT_B line to deassert 2595 after PROB_B has been deasserted during a Virtex II 2596 FPGA configuration sequence. The default time is 500 2597 ms. 2598 2599 CONFIG_SYS_FPGA_WAIT_BUSY 2600 2601 Maximum time to wait for BUSY to deassert during 2602 Virtex II FPGA configuration. The default is 5 ms. 2603 2604 CONFIG_SYS_FPGA_WAIT_CONFIG 2605 2606 Time to wait after FPGA configuration. The default is 2607 200 ms. 2608 2609- Configuration Management: 2610 CONFIG_IDENT_STRING 2611 2612 If defined, this string will be added to the U-Boot 2613 version information (U_BOOT_VERSION) 2614 2615- Vendor Parameter Protection: 2616 2617 U-Boot considers the values of the environment 2618 variables "serial#" (Board Serial Number) and 2619 "ethaddr" (Ethernet Address) to be parameters that 2620 are set once by the board vendor / manufacturer, and 2621 protects these variables from casual modification by 2622 the user. Once set, these variables are read-only, 2623 and write or delete attempts are rejected. You can 2624 change this behaviour: 2625 2626 If CONFIG_ENV_OVERWRITE is #defined in your config 2627 file, the write protection for vendor parameters is 2628 completely disabled. Anybody can change or delete 2629 these parameters. 2630 2631 Alternatively, if you #define _both_ CONFIG_ETHADDR 2632 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2633 Ethernet address is installed in the environment, 2634 which can be changed exactly ONCE by the user. [The 2635 serial# is unaffected by this, i. e. it remains 2636 read-only.] 2637 2638 The same can be accomplished in a more flexible way 2639 for any variable by configuring the type of access 2640 to allow for those variables in the ".flags" variable 2641 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2642 2643- Protected RAM: 2644 CONFIG_PRAM 2645 2646 Define this variable to enable the reservation of 2647 "protected RAM", i. e. RAM which is not overwritten 2648 by U-Boot. Define CONFIG_PRAM to hold the number of 2649 kB you want to reserve for pRAM. You can overwrite 2650 this default value by defining an environment 2651 variable "pram" to the number of kB you want to 2652 reserve. Note that the board info structure will 2653 still show the full amount of RAM. If pRAM is 2654 reserved, a new environment variable "mem" will 2655 automatically be defined to hold the amount of 2656 remaining RAM in a form that can be passed as boot 2657 argument to Linux, for instance like that: 2658 2659 setenv bootargs ... mem=\${mem} 2660 saveenv 2661 2662 This way you can tell Linux not to use this memory, 2663 either, which results in a memory region that will 2664 not be affected by reboots. 2665 2666 *WARNING* If your board configuration uses automatic 2667 detection of the RAM size, you must make sure that 2668 this memory test is non-destructive. So far, the 2669 following board configurations are known to be 2670 "pRAM-clean": 2671 2672 IVMS8, IVML24, SPD8xx, TQM8xxL, 2673 HERMES, IP860, RPXlite, LWMON, 2674 FLAGADM, TQM8260 2675 2676- Access to physical memory region (> 4GB) 2677 Some basic support is provided for operations on memory not 2678 normally accessible to U-Boot - e.g. some architectures 2679 support access to more than 4GB of memory on 32-bit 2680 machines using physical address extension or similar. 2681 Define CONFIG_PHYSMEM to access this basic support, which 2682 currently only supports clearing the memory. 2683 2684- Error Recovery: 2685 CONFIG_PANIC_HANG 2686 2687 Define this variable to stop the system in case of a 2688 fatal error, so that you have to reset it manually. 2689 This is probably NOT a good idea for an embedded 2690 system where you want the system to reboot 2691 automatically as fast as possible, but it may be 2692 useful during development since you can try to debug 2693 the conditions that lead to the situation. 2694 2695 CONFIG_NET_RETRY_COUNT 2696 2697 This variable defines the number of retries for 2698 network operations like ARP, RARP, TFTP, or BOOTP 2699 before giving up the operation. If not defined, a 2700 default value of 5 is used. 2701 2702 CONFIG_ARP_TIMEOUT 2703 2704 Timeout waiting for an ARP reply in milliseconds. 2705 2706 CONFIG_NFS_TIMEOUT 2707 2708 Timeout in milliseconds used in NFS protocol. 2709 If you encounter "ERROR: Cannot umount" in nfs command, 2710 try longer timeout such as 2711 #define CONFIG_NFS_TIMEOUT 10000UL 2712 2713- Command Interpreter: 2714 CONFIG_AUTO_COMPLETE 2715 2716 Enable auto completion of commands using TAB. 2717 2718 Note that this feature has NOT been implemented yet 2719 for the "hush" shell. 2720 2721 2722 CONFIG_SYS_HUSH_PARSER 2723 2724 Define this variable to enable the "hush" shell (from 2725 Busybox) as command line interpreter, thus enabling 2726 powerful command line syntax like 2727 if...then...else...fi conditionals or `&&' and '||' 2728 constructs ("shell scripts"). 2729 2730 If undefined, you get the old, much simpler behaviour 2731 with a somewhat smaller memory footprint. 2732 2733 2734 CONFIG_SYS_PROMPT_HUSH_PS2 2735 2736 This defines the secondary prompt string, which is 2737 printed when the command interpreter needs more input 2738 to complete a command. Usually "> ". 2739 2740 Note: 2741 2742 In the current implementation, the local variables 2743 space and global environment variables space are 2744 separated. Local variables are those you define by 2745 simply typing `name=value'. To access a local 2746 variable later on, you have write `$name' or 2747 `${name}'; to execute the contents of a variable 2748 directly type `$name' at the command prompt. 2749 2750 Global environment variables are those you use 2751 setenv/printenv to work with. To run a command stored 2752 in such a variable, you need to use the run command, 2753 and you must not use the '$' sign to access them. 2754 2755 To store commands and special characters in a 2756 variable, please use double quotation marks 2757 surrounding the whole text of the variable, instead 2758 of the backslashes before semicolons and special 2759 symbols. 2760 2761- Commandline Editing and History: 2762 CONFIG_CMDLINE_EDITING 2763 2764 Enable editing and History functions for interactive 2765 commandline input operations 2766 2767- Default Environment: 2768 CONFIG_EXTRA_ENV_SETTINGS 2769 2770 Define this to contain any number of null terminated 2771 strings (variable = value pairs) that will be part of 2772 the default environment compiled into the boot image. 2773 2774 For example, place something like this in your 2775 board's config file: 2776 2777 #define CONFIG_EXTRA_ENV_SETTINGS \ 2778 "myvar1=value1\0" \ 2779 "myvar2=value2\0" 2780 2781 Warning: This method is based on knowledge about the 2782 internal format how the environment is stored by the 2783 U-Boot code. This is NOT an official, exported 2784 interface! Although it is unlikely that this format 2785 will change soon, there is no guarantee either. 2786 You better know what you are doing here. 2787 2788 Note: overly (ab)use of the default environment is 2789 discouraged. Make sure to check other ways to preset 2790 the environment like the "source" command or the 2791 boot command first. 2792 2793 CONFIG_ENV_VARS_UBOOT_CONFIG 2794 2795 Define this in order to add variables describing the 2796 U-Boot build configuration to the default environment. 2797 These will be named arch, cpu, board, vendor, and soc. 2798 2799 Enabling this option will cause the following to be defined: 2800 2801 - CONFIG_SYS_ARCH 2802 - CONFIG_SYS_CPU 2803 - CONFIG_SYS_BOARD 2804 - CONFIG_SYS_VENDOR 2805 - CONFIG_SYS_SOC 2806 2807 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2808 2809 Define this in order to add variables describing certain 2810 run-time determined information about the hardware to the 2811 environment. These will be named board_name, board_rev. 2812 2813 CONFIG_DELAY_ENVIRONMENT 2814 2815 Normally the environment is loaded when the board is 2816 intialised so that it is available to U-Boot. This inhibits 2817 that so that the environment is not available until 2818 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2819 this is instead controlled by the value of 2820 /config/load-environment. 2821 2822- DataFlash Support: 2823 CONFIG_HAS_DATAFLASH 2824 2825 Defining this option enables DataFlash features and 2826 allows to read/write in Dataflash via the standard 2827 commands cp, md... 2828 2829- Serial Flash support 2830 CONFIG_CMD_SF 2831 2832 Defining this option enables SPI flash commands 2833 'sf probe/read/write/erase/update'. 2834 2835 Usage requires an initial 'probe' to define the serial 2836 flash parameters, followed by read/write/erase/update 2837 commands. 2838 2839 The following defaults may be provided by the platform 2840 to handle the common case when only a single serial 2841 flash is present on the system. 2842 2843 CONFIG_SF_DEFAULT_BUS Bus identifier 2844 CONFIG_SF_DEFAULT_CS Chip-select 2845 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2846 CONFIG_SF_DEFAULT_SPEED in Hz 2847 2848 CONFIG_CMD_SF_TEST 2849 2850 Define this option to include a destructive SPI flash 2851 test ('sf test'). 2852 2853 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg 2854 2855 Define this option to use the Bank addr/Extended addr 2856 support on SPI flashes which has size > 16Mbytes. 2857 2858 CONFIG_SF_DUAL_FLASH Dual flash memories 2859 2860 Define this option to use dual flash support where two flash 2861 memories can be connected with a given cs line. 2862 currently Xilinx Zynq qspi support these type of connections. 2863 2864- SystemACE Support: 2865 CONFIG_SYSTEMACE 2866 2867 Adding this option adds support for Xilinx SystemACE 2868 chips attached via some sort of local bus. The address 2869 of the chip must also be defined in the 2870 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2871 2872 #define CONFIG_SYSTEMACE 2873 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2874 2875 When SystemACE support is added, the "ace" device type 2876 becomes available to the fat commands, i.e. fatls. 2877 2878- TFTP Fixed UDP Port: 2879 CONFIG_TFTP_PORT 2880 2881 If this is defined, the environment variable tftpsrcp 2882 is used to supply the TFTP UDP source port value. 2883 If tftpsrcp isn't defined, the normal pseudo-random port 2884 number generator is used. 2885 2886 Also, the environment variable tftpdstp is used to supply 2887 the TFTP UDP destination port value. If tftpdstp isn't 2888 defined, the normal port 69 is used. 2889 2890 The purpose for tftpsrcp is to allow a TFTP server to 2891 blindly start the TFTP transfer using the pre-configured 2892 target IP address and UDP port. This has the effect of 2893 "punching through" the (Windows XP) firewall, allowing 2894 the remainder of the TFTP transfer to proceed normally. 2895 A better solution is to properly configure the firewall, 2896 but sometimes that is not allowed. 2897 2898- Hashing support: 2899 CONFIG_CMD_HASH 2900 2901 This enables a generic 'hash' command which can produce 2902 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2903 2904 CONFIG_HASH_VERIFY 2905 2906 Enable the hash verify command (hash -v). This adds to code 2907 size a little. 2908 2909 CONFIG_SHA1 - support SHA1 hashing 2910 CONFIG_SHA256 - support SHA256 hashing 2911 2912 Note: There is also a sha1sum command, which should perhaps 2913 be deprecated in favour of 'hash sha1'. 2914 2915- Freescale i.MX specific commands: 2916 CONFIG_CMD_HDMIDETECT 2917 This enables 'hdmidet' command which returns true if an 2918 HDMI monitor is detected. This command is i.MX 6 specific. 2919 2920 CONFIG_CMD_BMODE 2921 This enables the 'bmode' (bootmode) command for forcing 2922 a boot from specific media. 2923 2924 This is useful for forcing the ROM's usb downloader to 2925 activate upon a watchdog reset which is nice when iterating 2926 on U-Boot. Using the reset button or running bmode normal 2927 will set it back to normal. This command currently 2928 supports i.MX53 and i.MX6. 2929 2930- Signing support: 2931 CONFIG_RSA 2932 2933 This enables the RSA algorithm used for FIT image verification 2934 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 2935 2936 The signing part is build into mkimage regardless of this 2937 option. 2938 2939- bootcount support: 2940 CONFIG_BOOTCOUNT_LIMIT 2941 2942 This enables the bootcounter support, see: 2943 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2944 2945 CONFIG_AT91SAM9XE 2946 enable special bootcounter support on at91sam9xe based boards. 2947 CONFIG_BLACKFIN 2948 enable special bootcounter support on blackfin based boards. 2949 CONFIG_SOC_DA8XX 2950 enable special bootcounter support on da850 based boards. 2951 CONFIG_BOOTCOUNT_RAM 2952 enable support for the bootcounter in RAM 2953 CONFIG_BOOTCOUNT_I2C 2954 enable support for the bootcounter on an i2c (like RTC) device. 2955 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2956 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2957 the bootcounter. 2958 CONFIG_BOOTCOUNT_ALEN = address len 2959 2960- Show boot progress: 2961 CONFIG_SHOW_BOOT_PROGRESS 2962 2963 Defining this option allows to add some board- 2964 specific code (calling a user-provided function 2965 "show_boot_progress(int)") that enables you to show 2966 the system's boot progress on some display (for 2967 example, some LED's) on your board. At the moment, 2968 the following checkpoints are implemented: 2969 2970- Detailed boot stage timing 2971 CONFIG_BOOTSTAGE 2972 Define this option to get detailed timing of each stage 2973 of the boot process. 2974 2975 CONFIG_BOOTSTAGE_USER_COUNT 2976 This is the number of available user bootstage records. 2977 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 2978 a new ID will be allocated from this stash. If you exceed 2979 the limit, recording will stop. 2980 2981 CONFIG_BOOTSTAGE_REPORT 2982 Define this to print a report before boot, similar to this: 2983 2984 Timer summary in microseconds: 2985 Mark Elapsed Stage 2986 0 0 reset 2987 3,575,678 3,575,678 board_init_f start 2988 3,575,695 17 arch_cpu_init A9 2989 3,575,777 82 arch_cpu_init done 2990 3,659,598 83,821 board_init_r start 2991 3,910,375 250,777 main_loop 2992 29,916,167 26,005,792 bootm_start 2993 30,361,327 445,160 start_kernel 2994 2995 CONFIG_CMD_BOOTSTAGE 2996 Add a 'bootstage' command which supports printing a report 2997 and un/stashing of bootstage data. 2998 2999 CONFIG_BOOTSTAGE_FDT 3000 Stash the bootstage information in the FDT. A root 'bootstage' 3001 node is created with each bootstage id as a child. Each child 3002 has a 'name' property and either 'mark' containing the 3003 mark time in microsecond, or 'accum' containing the 3004 accumulated time for that bootstage id in microseconds. 3005 For example: 3006 3007 bootstage { 3008 154 { 3009 name = "board_init_f"; 3010 mark = <3575678>; 3011 }; 3012 170 { 3013 name = "lcd"; 3014 accum = <33482>; 3015 }; 3016 }; 3017 3018 Code in the Linux kernel can find this in /proc/devicetree. 3019 3020Legacy uImage format: 3021 3022 Arg Where When 3023 1 common/cmd_bootm.c before attempting to boot an image 3024 -1 common/cmd_bootm.c Image header has bad magic number 3025 2 common/cmd_bootm.c Image header has correct magic number 3026 -2 common/cmd_bootm.c Image header has bad checksum 3027 3 common/cmd_bootm.c Image header has correct checksum 3028 -3 common/cmd_bootm.c Image data has bad checksum 3029 4 common/cmd_bootm.c Image data has correct checksum 3030 -4 common/cmd_bootm.c Image is for unsupported architecture 3031 5 common/cmd_bootm.c Architecture check OK 3032 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3033 6 common/cmd_bootm.c Image Type check OK 3034 -6 common/cmd_bootm.c gunzip uncompression error 3035 -7 common/cmd_bootm.c Unimplemented compression type 3036 7 common/cmd_bootm.c Uncompression OK 3037 8 common/cmd_bootm.c No uncompress/copy overwrite error 3038 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3039 3040 9 common/image.c Start initial ramdisk verification 3041 -10 common/image.c Ramdisk header has bad magic number 3042 -11 common/image.c Ramdisk header has bad checksum 3043 10 common/image.c Ramdisk header is OK 3044 -12 common/image.c Ramdisk data has bad checksum 3045 11 common/image.c Ramdisk data has correct checksum 3046 12 common/image.c Ramdisk verification complete, start loading 3047 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3048 13 common/image.c Start multifile image verification 3049 14 common/image.c No initial ramdisk, no multifile, continue. 3050 3051 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3052 3053 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3054 -31 post/post.c POST test failed, detected by post_output_backlog() 3055 -32 post/post.c POST test failed, detected by post_run_single() 3056 3057 34 common/cmd_doc.c before loading a Image from a DOC device 3058 -35 common/cmd_doc.c Bad usage of "doc" command 3059 35 common/cmd_doc.c correct usage of "doc" command 3060 -36 common/cmd_doc.c No boot device 3061 36 common/cmd_doc.c correct boot device 3062 -37 common/cmd_doc.c Unknown Chip ID on boot device 3063 37 common/cmd_doc.c correct chip ID found, device available 3064 -38 common/cmd_doc.c Read Error on boot device 3065 38 common/cmd_doc.c reading Image header from DOC device OK 3066 -39 common/cmd_doc.c Image header has bad magic number 3067 39 common/cmd_doc.c Image header has correct magic number 3068 -40 common/cmd_doc.c Error reading Image from DOC device 3069 40 common/cmd_doc.c Image header has correct magic number 3070 41 common/cmd_ide.c before loading a Image from a IDE device 3071 -42 common/cmd_ide.c Bad usage of "ide" command 3072 42 common/cmd_ide.c correct usage of "ide" command 3073 -43 common/cmd_ide.c No boot device 3074 43 common/cmd_ide.c boot device found 3075 -44 common/cmd_ide.c Device not available 3076 44 common/cmd_ide.c Device available 3077 -45 common/cmd_ide.c wrong partition selected 3078 45 common/cmd_ide.c partition selected 3079 -46 common/cmd_ide.c Unknown partition table 3080 46 common/cmd_ide.c valid partition table found 3081 -47 common/cmd_ide.c Invalid partition type 3082 47 common/cmd_ide.c correct partition type 3083 -48 common/cmd_ide.c Error reading Image Header on boot device 3084 48 common/cmd_ide.c reading Image Header from IDE device OK 3085 -49 common/cmd_ide.c Image header has bad magic number 3086 49 common/cmd_ide.c Image header has correct magic number 3087 -50 common/cmd_ide.c Image header has bad checksum 3088 50 common/cmd_ide.c Image header has correct checksum 3089 -51 common/cmd_ide.c Error reading Image from IDE device 3090 51 common/cmd_ide.c reading Image from IDE device OK 3091 52 common/cmd_nand.c before loading a Image from a NAND device 3092 -53 common/cmd_nand.c Bad usage of "nand" command 3093 53 common/cmd_nand.c correct usage of "nand" command 3094 -54 common/cmd_nand.c No boot device 3095 54 common/cmd_nand.c boot device found 3096 -55 common/cmd_nand.c Unknown Chip ID on boot device 3097 55 common/cmd_nand.c correct chip ID found, device available 3098 -56 common/cmd_nand.c Error reading Image Header on boot device 3099 56 common/cmd_nand.c reading Image Header from NAND device OK 3100 -57 common/cmd_nand.c Image header has bad magic number 3101 57 common/cmd_nand.c Image header has correct magic number 3102 -58 common/cmd_nand.c Error reading Image from NAND device 3103 58 common/cmd_nand.c reading Image from NAND device OK 3104 3105 -60 common/env_common.c Environment has a bad CRC, using default 3106 3107 64 net/eth.c starting with Ethernet configuration. 3108 -64 net/eth.c no Ethernet found. 3109 65 net/eth.c Ethernet found. 3110 3111 -80 common/cmd_net.c usage wrong 3112 80 common/cmd_net.c before calling NetLoop() 3113 -81 common/cmd_net.c some error in NetLoop() occurred 3114 81 common/cmd_net.c NetLoop() back without error 3115 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3116 82 common/cmd_net.c trying automatic boot 3117 83 common/cmd_net.c running "source" command 3118 -83 common/cmd_net.c some error in automatic boot or "source" command 3119 84 common/cmd_net.c end without errors 3120 3121FIT uImage format: 3122 3123 Arg Where When 3124 100 common/cmd_bootm.c Kernel FIT Image has correct format 3125 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3126 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3127 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3128 102 common/cmd_bootm.c Kernel unit name specified 3129 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3130 103 common/cmd_bootm.c Found configuration node 3131 104 common/cmd_bootm.c Got kernel subimage node offset 3132 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3133 105 common/cmd_bootm.c Kernel subimage hash verification OK 3134 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3135 106 common/cmd_bootm.c Architecture check OK 3136 -106 common/cmd_bootm.c Kernel subimage has wrong type 3137 107 common/cmd_bootm.c Kernel subimage type OK 3138 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3139 108 common/cmd_bootm.c Got kernel subimage data/size 3140 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3141 -109 common/cmd_bootm.c Can't get kernel subimage type 3142 -110 common/cmd_bootm.c Can't get kernel subimage comp 3143 -111 common/cmd_bootm.c Can't get kernel subimage os 3144 -112 common/cmd_bootm.c Can't get kernel subimage load address 3145 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3146 3147 120 common/image.c Start initial ramdisk verification 3148 -120 common/image.c Ramdisk FIT image has incorrect format 3149 121 common/image.c Ramdisk FIT image has correct format 3150 122 common/image.c No ramdisk subimage unit name, using configuration 3151 -122 common/image.c Can't get configuration for ramdisk subimage 3152 123 common/image.c Ramdisk unit name specified 3153 -124 common/image.c Can't get ramdisk subimage node offset 3154 125 common/image.c Got ramdisk subimage node offset 3155 -125 common/image.c Ramdisk subimage hash verification failed 3156 126 common/image.c Ramdisk subimage hash verification OK 3157 -126 common/image.c Ramdisk subimage for unsupported architecture 3158 127 common/image.c Architecture check OK 3159 -127 common/image.c Can't get ramdisk subimage data/size 3160 128 common/image.c Got ramdisk subimage data/size 3161 129 common/image.c Can't get ramdisk load address 3162 -129 common/image.c Got ramdisk load address 3163 3164 -130 common/cmd_doc.c Incorrect FIT image format 3165 131 common/cmd_doc.c FIT image format OK 3166 3167 -140 common/cmd_ide.c Incorrect FIT image format 3168 141 common/cmd_ide.c FIT image format OK 3169 3170 -150 common/cmd_nand.c Incorrect FIT image format 3171 151 common/cmd_nand.c FIT image format OK 3172 3173- FIT image support: 3174 CONFIG_FIT 3175 Enable support for the FIT uImage format. 3176 3177 CONFIG_FIT_BEST_MATCH 3178 When no configuration is explicitly selected, default to the 3179 one whose fdt's compatibility field best matches that of 3180 U-Boot itself. A match is considered "best" if it matches the 3181 most specific compatibility entry of U-Boot's fdt's root node. 3182 The order of entries in the configuration's fdt is ignored. 3183 3184 CONFIG_FIT_SIGNATURE 3185 This option enables signature verification of FIT uImages, 3186 using a hash signed and verified using RSA. See 3187 doc/uImage.FIT/signature.txt for more details. 3188 3189- Standalone program support: 3190 CONFIG_STANDALONE_LOAD_ADDR 3191 3192 This option defines a board specific value for the 3193 address where standalone program gets loaded, thus 3194 overwriting the architecture dependent default 3195 settings. 3196 3197- Frame Buffer Address: 3198 CONFIG_FB_ADDR 3199 3200 Define CONFIG_FB_ADDR if you want to use specific 3201 address for frame buffer. This is typically the case 3202 when using a graphics controller has separate video 3203 memory. U-Boot will then place the frame buffer at 3204 the given address instead of dynamically reserving it 3205 in system RAM by calling lcd_setmem(), which grabs 3206 the memory for the frame buffer depending on the 3207 configured panel size. 3208 3209 Please see board_init_f function. 3210 3211- Automatic software updates via TFTP server 3212 CONFIG_UPDATE_TFTP 3213 CONFIG_UPDATE_TFTP_CNT_MAX 3214 CONFIG_UPDATE_TFTP_MSEC_MAX 3215 3216 These options enable and control the auto-update feature; 3217 for a more detailed description refer to doc/README.update. 3218 3219- MTD Support (mtdparts command, UBI support) 3220 CONFIG_MTD_DEVICE 3221 3222 Adds the MTD device infrastructure from the Linux kernel. 3223 Needed for mtdparts command support. 3224 3225 CONFIG_MTD_PARTITIONS 3226 3227 Adds the MTD partitioning infrastructure from the Linux 3228 kernel. Needed for UBI support. 3229 3230- UBI support 3231 CONFIG_CMD_UBI 3232 3233 Adds commands for interacting with MTD partitions formatted 3234 with the UBI flash translation layer 3235 3236 Requires also defining CONFIG_RBTREE 3237 3238 CONFIG_UBI_SILENCE_MSG 3239 3240 Make the verbose messages from UBI stop printing. This leaves 3241 warnings and errors enabled. 3242 3243- UBIFS support 3244 CONFIG_CMD_UBIFS 3245 3246 Adds commands for interacting with UBI volumes formatted as 3247 UBIFS. UBIFS is read-only in u-boot. 3248 3249 Requires UBI support as well as CONFIG_LZO 3250 3251 CONFIG_UBIFS_SILENCE_MSG 3252 3253 Make the verbose messages from UBIFS stop printing. This leaves 3254 warnings and errors enabled. 3255 3256- SPL framework 3257 CONFIG_SPL 3258 Enable building of SPL globally. 3259 3260 CONFIG_SPL_LDSCRIPT 3261 LDSCRIPT for linking the SPL binary. 3262 3263 CONFIG_SPL_MAX_FOOTPRINT 3264 Maximum size in memory allocated to the SPL, BSS included. 3265 When defined, the linker checks that the actual memory 3266 used by SPL from _start to __bss_end does not exceed it. 3267 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3268 must not be both defined at the same time. 3269 3270 CONFIG_SPL_MAX_SIZE 3271 Maximum size of the SPL image (text, data, rodata, and 3272 linker lists sections), BSS excluded. 3273 When defined, the linker checks that the actual size does 3274 not exceed it. 3275 3276 CONFIG_SPL_TEXT_BASE 3277 TEXT_BASE for linking the SPL binary. 3278 3279 CONFIG_SPL_RELOC_TEXT_BASE 3280 Address to relocate to. If unspecified, this is equal to 3281 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3282 3283 CONFIG_SPL_BSS_START_ADDR 3284 Link address for the BSS within the SPL binary. 3285 3286 CONFIG_SPL_BSS_MAX_SIZE 3287 Maximum size in memory allocated to the SPL BSS. 3288 When defined, the linker checks that the actual memory used 3289 by SPL from __bss_start to __bss_end does not exceed it. 3290 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3291 must not be both defined at the same time. 3292 3293 CONFIG_SPL_STACK 3294 Adress of the start of the stack SPL will use 3295 3296 CONFIG_SPL_RELOC_STACK 3297 Adress of the start of the stack SPL will use after 3298 relocation. If unspecified, this is equal to 3299 CONFIG_SPL_STACK. 3300 3301 CONFIG_SYS_SPL_MALLOC_START 3302 Starting address of the malloc pool used in SPL. 3303 3304 CONFIG_SYS_SPL_MALLOC_SIZE 3305 The size of the malloc pool used in SPL. 3306 3307 CONFIG_SPL_FRAMEWORK 3308 Enable the SPL framework under common/. This framework 3309 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3310 NAND loading of the Linux Kernel. 3311 3312 CONFIG_SPL_OS_BOOT 3313 Enable booting directly to an OS from SPL. 3314 See also: doc/README.falcon 3315 3316 CONFIG_SPL_DISPLAY_PRINT 3317 For ARM, enable an optional function to print more information 3318 about the running system. 3319 3320 CONFIG_SPL_INIT_MINIMAL 3321 Arch init code should be built for a very small image 3322 3323 CONFIG_SPL_LIBCOMMON_SUPPORT 3324 Support for common/libcommon.o in SPL binary 3325 3326 CONFIG_SPL_LIBDISK_SUPPORT 3327 Support for disk/libdisk.o in SPL binary 3328 3329 CONFIG_SPL_I2C_SUPPORT 3330 Support for drivers/i2c/libi2c.o in SPL binary 3331 3332 CONFIG_SPL_GPIO_SUPPORT 3333 Support for drivers/gpio/libgpio.o in SPL binary 3334 3335 CONFIG_SPL_MMC_SUPPORT 3336 Support for drivers/mmc/libmmc.o in SPL binary 3337 3338 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3339 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3340 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION 3341 Address, size and partition on the MMC to load U-Boot from 3342 when the MMC is being used in raw mode. 3343 3344 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3345 Sector to load kernel uImage from when MMC is being 3346 used in raw mode (for Falcon mode) 3347 3348 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3349 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3350 Sector and number of sectors to load kernel argument 3351 parameters from when MMC is being used in raw mode 3352 (for falcon mode) 3353 3354 CONFIG_SPL_FAT_SUPPORT 3355 Support for fs/fat/libfat.o in SPL binary 3356 3357 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME 3358 Filename to read to load U-Boot when reading from FAT 3359 3360 CONFIG_SPL_FAT_LOAD_KERNEL_NAME 3361 Filename to read to load kernel uImage when reading 3362 from FAT (for Falcon mode) 3363 3364 CONFIG_SPL_FAT_LOAD_ARGS_NAME 3365 Filename to read to load kernel argument parameters 3366 when reading from FAT (for Falcon mode) 3367 3368 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3369 Set this for NAND SPL on PPC mpc83xx targets, so that 3370 start.S waits for the rest of the SPL to load before 3371 continuing (the hardware starts execution after just 3372 loading the first page rather than the full 4K). 3373 3374 CONFIG_SPL_SKIP_RELOCATE 3375 Avoid SPL relocation 3376 3377 CONFIG_SPL_NAND_BASE 3378 Include nand_base.c in the SPL. Requires 3379 CONFIG_SPL_NAND_DRIVERS. 3380 3381 CONFIG_SPL_NAND_DRIVERS 3382 SPL uses normal NAND drivers, not minimal drivers. 3383 3384 CONFIG_SPL_NAND_ECC 3385 Include standard software ECC in the SPL 3386 3387 CONFIG_SPL_NAND_SIMPLE 3388 Support for NAND boot using simple NAND drivers that 3389 expose the cmd_ctrl() interface. 3390 3391 CONFIG_SPL_MTD_SUPPORT 3392 Support for the MTD subsystem within SPL. Useful for 3393 environment on NAND support within SPL. 3394 3395 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3396 Set for the SPL on PPC mpc8xxx targets, support for 3397 drivers/ddr/fsl/libddr.o in SPL binary. 3398 3399 CONFIG_SPL_COMMON_INIT_DDR 3400 Set for common ddr init with serial presence detect in 3401 SPL binary. 3402 3403 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3404 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3405 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3406 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3407 CONFIG_SYS_NAND_ECCBYTES 3408 Defines the size and behavior of the NAND that SPL uses 3409 to read U-Boot 3410 3411 CONFIG_SPL_NAND_BOOT 3412 Add support NAND boot 3413 3414 CONFIG_SYS_NAND_U_BOOT_OFFS 3415 Location in NAND to read U-Boot from 3416 3417 CONFIG_SYS_NAND_U_BOOT_DST 3418 Location in memory to load U-Boot to 3419 3420 CONFIG_SYS_NAND_U_BOOT_SIZE 3421 Size of image to load 3422 3423 CONFIG_SYS_NAND_U_BOOT_START 3424 Entry point in loaded image to jump to 3425 3426 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3427 Define this if you need to first read the OOB and then the 3428 data. This is used for example on davinci plattforms. 3429 3430 CONFIG_SPL_OMAP3_ID_NAND 3431 Support for an OMAP3-specific set of functions to return the 3432 ID and MFR of the first attached NAND chip, if present. 3433 3434 CONFIG_SPL_SERIAL_SUPPORT 3435 Support for drivers/serial/libserial.o in SPL binary 3436 3437 CONFIG_SPL_SPI_FLASH_SUPPORT 3438 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3439 3440 CONFIG_SPL_SPI_SUPPORT 3441 Support for drivers/spi/libspi.o in SPL binary 3442 3443 CONFIG_SPL_RAM_DEVICE 3444 Support for running image already present in ram, in SPL binary 3445 3446 CONFIG_SPL_LIBGENERIC_SUPPORT 3447 Support for lib/libgeneric.o in SPL binary 3448 3449 CONFIG_SPL_ENV_SUPPORT 3450 Support for the environment operating in SPL binary 3451 3452 CONFIG_SPL_NET_SUPPORT 3453 Support for the net/libnet.o in SPL binary. 3454 It conflicts with SPL env from storage medium specified by 3455 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3456 3457 CONFIG_SPL_PAD_TO 3458 Image offset to which the SPL should be padded before appending 3459 the SPL payload. By default, this is defined as 3460 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3461 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3462 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3463 3464 CONFIG_SPL_TARGET 3465 Final target image containing SPL and payload. Some SPLs 3466 use an arch-specific makefile fragment instead, for 3467 example if more than one image needs to be produced. 3468 3469 CONFIG_FIT_SPL_PRINT 3470 Printing information about a FIT image adds quite a bit of 3471 code to SPL. So this is normally disabled in SPL. Use this 3472 option to re-enable it. This will affect the output of the 3473 bootm command when booting a FIT image. 3474 3475- TPL framework 3476 CONFIG_TPL 3477 Enable building of TPL globally. 3478 3479 CONFIG_TPL_PAD_TO 3480 Image offset to which the TPL should be padded before appending 3481 the TPL payload. By default, this is defined as 3482 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3483 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3484 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3485 3486Modem Support: 3487-------------- 3488 3489[so far only for SMDK2400 boards] 3490 3491- Modem support enable: 3492 CONFIG_MODEM_SUPPORT 3493 3494- RTS/CTS Flow control enable: 3495 CONFIG_HWFLOW 3496 3497- Modem debug support: 3498 CONFIG_MODEM_SUPPORT_DEBUG 3499 3500 Enables debugging stuff (char screen[1024], dbg()) 3501 for modem support. Useful only with BDI2000. 3502 3503- Interrupt support (PPC): 3504 3505 There are common interrupt_init() and timer_interrupt() 3506 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3507 for CPU specific initialization. interrupt_init_cpu() 3508 should set decrementer_count to appropriate value. If 3509 CPU resets decrementer automatically after interrupt 3510 (ppc4xx) it should set decrementer_count to zero. 3511 timer_interrupt() calls timer_interrupt_cpu() for CPU 3512 specific handling. If board has watchdog / status_led 3513 / other_activity_monitor it works automatically from 3514 general timer_interrupt(). 3515 3516- General: 3517 3518 In the target system modem support is enabled when a 3519 specific key (key combination) is pressed during 3520 power-on. Otherwise U-Boot will boot normally 3521 (autoboot). The key_pressed() function is called from 3522 board_init(). Currently key_pressed() is a dummy 3523 function, returning 1 and thus enabling modem 3524 initialization. 3525 3526 If there are no modem init strings in the 3527 environment, U-Boot proceed to autoboot; the 3528 previous output (banner, info printfs) will be 3529 suppressed, though. 3530 3531 See also: doc/README.Modem 3532 3533Board initialization settings: 3534------------------------------ 3535 3536During Initialization u-boot calls a number of board specific functions 3537to allow the preparation of board specific prerequisites, e.g. pin setup 3538before drivers are initialized. To enable these callbacks the 3539following configuration macros have to be defined. Currently this is 3540architecture specific, so please check arch/your_architecture/lib/board.c 3541typically in board_init_f() and board_init_r(). 3542 3543- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3544- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3545- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3546- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3547 3548Configuration Settings: 3549----------------------- 3550 3551- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3552 Optionally it can be defined to support 64-bit memory commands. 3553 3554- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3555 undefine this when you're short of memory. 3556 3557- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3558 width of the commands listed in the 'help' command output. 3559 3560- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3561 prompt for user input. 3562 3563- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3564 3565- CONFIG_SYS_PBSIZE: Buffer size for Console output 3566 3567- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3568 3569- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3570 the application (usually a Linux kernel) when it is 3571 booted 3572 3573- CONFIG_SYS_BAUDRATE_TABLE: 3574 List of legal baudrate settings for this board. 3575 3576- CONFIG_SYS_CONSOLE_INFO_QUIET 3577 Suppress display of console information at boot. 3578 3579- CONFIG_SYS_CONSOLE_IS_IN_ENV 3580 If the board specific function 3581 extern int overwrite_console (void); 3582 returns 1, the stdin, stderr and stdout are switched to the 3583 serial port, else the settings in the environment are used. 3584 3585- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3586 Enable the call to overwrite_console(). 3587 3588- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3589 Enable overwrite of previous console environment settings. 3590 3591- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3592 Begin and End addresses of the area used by the 3593 simple memory test. 3594 3595- CONFIG_SYS_ALT_MEMTEST: 3596 Enable an alternate, more extensive memory test. 3597 3598- CONFIG_SYS_MEMTEST_SCRATCH: 3599 Scratch address used by the alternate memory test 3600 You only need to set this if address zero isn't writeable 3601 3602- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3603 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3604 this specified memory area will get subtracted from the top 3605 (end) of RAM and won't get "touched" at all by U-Boot. By 3606 fixing up gd->ram_size the Linux kernel should gets passed 3607 the now "corrected" memory size and won't touch it either. 3608 This should work for arch/ppc and arch/powerpc. Only Linux 3609 board ports in arch/powerpc with bootwrapper support that 3610 recalculate the memory size from the SDRAM controller setup 3611 will have to get fixed in Linux additionally. 3612 3613 This option can be used as a workaround for the 440EPx/GRx 3614 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3615 be touched. 3616 3617 WARNING: Please make sure that this value is a multiple of 3618 the Linux page size (normally 4k). If this is not the case, 3619 then the end address of the Linux memory will be located at a 3620 non page size aligned address and this could cause major 3621 problems. 3622 3623- CONFIG_SYS_LOADS_BAUD_CHANGE: 3624 Enable temporary baudrate change while serial download 3625 3626- CONFIG_SYS_SDRAM_BASE: 3627 Physical start address of SDRAM. _Must_ be 0 here. 3628 3629- CONFIG_SYS_MBIO_BASE: 3630 Physical start address of Motherboard I/O (if using a 3631 Cogent motherboard) 3632 3633- CONFIG_SYS_FLASH_BASE: 3634 Physical start address of Flash memory. 3635 3636- CONFIG_SYS_MONITOR_BASE: 3637 Physical start address of boot monitor code (set by 3638 make config files to be same as the text base address 3639 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3640 CONFIG_SYS_FLASH_BASE when booting from flash. 3641 3642- CONFIG_SYS_MONITOR_LEN: 3643 Size of memory reserved for monitor code, used to 3644 determine _at_compile_time_ (!) if the environment is 3645 embedded within the U-Boot image, or in a separate 3646 flash sector. 3647 3648- CONFIG_SYS_MALLOC_LEN: 3649 Size of DRAM reserved for malloc() use. 3650 3651- CONFIG_SYS_BOOTM_LEN: 3652 Normally compressed uImages are limited to an 3653 uncompressed size of 8 MBytes. If this is not enough, 3654 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3655 to adjust this setting to your needs. 3656 3657- CONFIG_SYS_BOOTMAPSZ: 3658 Maximum size of memory mapped by the startup code of 3659 the Linux kernel; all data that must be processed by 3660 the Linux kernel (bd_info, boot arguments, FDT blob if 3661 used) must be put below this limit, unless "bootm_low" 3662 environment variable is defined and non-zero. In such case 3663 all data for the Linux kernel must be between "bootm_low" 3664 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3665 variable "bootm_mapsize" will override the value of 3666 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3667 then the value in "bootm_size" will be used instead. 3668 3669- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3670 Enable initrd_high functionality. If defined then the 3671 initrd_high feature is enabled and the bootm ramdisk subcommand 3672 is enabled. 3673 3674- CONFIG_SYS_BOOT_GET_CMDLINE: 3675 Enables allocating and saving kernel cmdline in space between 3676 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3677 3678- CONFIG_SYS_BOOT_GET_KBD: 3679 Enables allocating and saving a kernel copy of the bd_info in 3680 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3681 3682- CONFIG_SYS_MAX_FLASH_BANKS: 3683 Max number of Flash memory banks 3684 3685- CONFIG_SYS_MAX_FLASH_SECT: 3686 Max number of sectors on a Flash chip 3687 3688- CONFIG_SYS_FLASH_ERASE_TOUT: 3689 Timeout for Flash erase operations (in ms) 3690 3691- CONFIG_SYS_FLASH_WRITE_TOUT: 3692 Timeout for Flash write operations (in ms) 3693 3694- CONFIG_SYS_FLASH_LOCK_TOUT 3695 Timeout for Flash set sector lock bit operation (in ms) 3696 3697- CONFIG_SYS_FLASH_UNLOCK_TOUT 3698 Timeout for Flash clear lock bits operation (in ms) 3699 3700- CONFIG_SYS_FLASH_PROTECTION 3701 If defined, hardware flash sectors protection is used 3702 instead of U-Boot software protection. 3703 3704- CONFIG_SYS_DIRECT_FLASH_TFTP: 3705 3706 Enable TFTP transfers directly to flash memory; 3707 without this option such a download has to be 3708 performed in two steps: (1) download to RAM, and (2) 3709 copy from RAM to flash. 3710 3711 The two-step approach is usually more reliable, since 3712 you can check if the download worked before you erase 3713 the flash, but in some situations (when system RAM is 3714 too limited to allow for a temporary copy of the 3715 downloaded image) this option may be very useful. 3716 3717- CONFIG_SYS_FLASH_CFI: 3718 Define if the flash driver uses extra elements in the 3719 common flash structure for storing flash geometry. 3720 3721- CONFIG_FLASH_CFI_DRIVER 3722 This option also enables the building of the cfi_flash driver 3723 in the drivers directory 3724 3725- CONFIG_FLASH_CFI_MTD 3726 This option enables the building of the cfi_mtd driver 3727 in the drivers directory. The driver exports CFI flash 3728 to the MTD layer. 3729 3730- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3731 Use buffered writes to flash. 3732 3733- CONFIG_FLASH_SPANSION_S29WS_N 3734 s29ws-n MirrorBit flash has non-standard addresses for buffered 3735 write commands. 3736 3737- CONFIG_SYS_FLASH_QUIET_TEST 3738 If this option is defined, the common CFI flash doesn't 3739 print it's warning upon not recognized FLASH banks. This 3740 is useful, if some of the configured banks are only 3741 optionally available. 3742 3743- CONFIG_FLASH_SHOW_PROGRESS 3744 If defined (must be an integer), print out countdown 3745 digits and dots. Recommended value: 45 (9..1) for 80 3746 column displays, 15 (3..1) for 40 column displays. 3747 3748- CONFIG_FLASH_VERIFY 3749 If defined, the content of the flash (destination) is compared 3750 against the source after the write operation. An error message 3751 will be printed when the contents are not identical. 3752 Please note that this option is useless in nearly all cases, 3753 since such flash programming errors usually are detected earlier 3754 while unprotecting/erasing/programming. Please only enable 3755 this option if you really know what you are doing. 3756 3757- CONFIG_SYS_RX_ETH_BUFFER: 3758 Defines the number of Ethernet receive buffers. On some 3759 Ethernet controllers it is recommended to set this value 3760 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3761 buffers can be full shortly after enabling the interface 3762 on high Ethernet traffic. 3763 Defaults to 4 if not defined. 3764 3765- CONFIG_ENV_MAX_ENTRIES 3766 3767 Maximum number of entries in the hash table that is used 3768 internally to store the environment settings. The default 3769 setting is supposed to be generous and should work in most 3770 cases. This setting can be used to tune behaviour; see 3771 lib/hashtable.c for details. 3772 3773- CONFIG_ENV_FLAGS_LIST_DEFAULT 3774- CONFIG_ENV_FLAGS_LIST_STATIC 3775 Enable validation of the values given to environment variables when 3776 calling env set. Variables can be restricted to only decimal, 3777 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3778 the variables can also be restricted to IP address or MAC address. 3779 3780 The format of the list is: 3781 type_attribute = [s|d|x|b|i|m] 3782 access_atribute = [a|r|o|c] 3783 attributes = type_attribute[access_atribute] 3784 entry = variable_name[:attributes] 3785 list = entry[,list] 3786 3787 The type attributes are: 3788 s - String (default) 3789 d - Decimal 3790 x - Hexadecimal 3791 b - Boolean ([1yYtT|0nNfF]) 3792 i - IP address 3793 m - MAC address 3794 3795 The access attributes are: 3796 a - Any (default) 3797 r - Read-only 3798 o - Write-once 3799 c - Change-default 3800 3801 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3802 Define this to a list (string) to define the ".flags" 3803 envirnoment variable in the default or embedded environment. 3804 3805 - CONFIG_ENV_FLAGS_LIST_STATIC 3806 Define this to a list (string) to define validation that 3807 should be done if an entry is not found in the ".flags" 3808 environment variable. To override a setting in the static 3809 list, simply add an entry for the same variable name to the 3810 ".flags" variable. 3811 3812- CONFIG_ENV_ACCESS_IGNORE_FORCE 3813 If defined, don't allow the -f switch to env set override variable 3814 access flags. 3815 3816- CONFIG_SYS_GENERIC_BOARD 3817 This selects the architecture-generic board system instead of the 3818 architecture-specific board files. It is intended to move boards 3819 to this new framework over time. Defining this will disable the 3820 arch/foo/lib/board.c file and use common/board_f.c and 3821 common/board_r.c instead. To use this option your architecture 3822 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in 3823 its config.mk file). If you find problems enabling this option on 3824 your board please report the problem and send patches! 3825 3826- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 3827 This is set by OMAP boards for the max time that reset should 3828 be asserted. See doc/README.omap-reset-time for details on how 3829 the value can be calulated on a given board. 3830 3831The following definitions that deal with the placement and management 3832of environment data (variable area); in general, we support the 3833following configurations: 3834 3835- CONFIG_BUILD_ENVCRC: 3836 3837 Builds up envcrc with the target environment so that external utils 3838 may easily extract it and embed it in final U-Boot images. 3839 3840- CONFIG_ENV_IS_IN_FLASH: 3841 3842 Define this if the environment is in flash memory. 3843 3844 a) The environment occupies one whole flash sector, which is 3845 "embedded" in the text segment with the U-Boot code. This 3846 happens usually with "bottom boot sector" or "top boot 3847 sector" type flash chips, which have several smaller 3848 sectors at the start or the end. For instance, such a 3849 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3850 such a case you would place the environment in one of the 3851 4 kB sectors - with U-Boot code before and after it. With 3852 "top boot sector" type flash chips, you would put the 3853 environment in one of the last sectors, leaving a gap 3854 between U-Boot and the environment. 3855 3856 - CONFIG_ENV_OFFSET: 3857 3858 Offset of environment data (variable area) to the 3859 beginning of flash memory; for instance, with bottom boot 3860 type flash chips the second sector can be used: the offset 3861 for this sector is given here. 3862 3863 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3864 3865 - CONFIG_ENV_ADDR: 3866 3867 This is just another way to specify the start address of 3868 the flash sector containing the environment (instead of 3869 CONFIG_ENV_OFFSET). 3870 3871 - CONFIG_ENV_SECT_SIZE: 3872 3873 Size of the sector containing the environment. 3874 3875 3876 b) Sometimes flash chips have few, equal sized, BIG sectors. 3877 In such a case you don't want to spend a whole sector for 3878 the environment. 3879 3880 - CONFIG_ENV_SIZE: 3881 3882 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3883 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3884 of this flash sector for the environment. This saves 3885 memory for the RAM copy of the environment. 3886 3887 It may also save flash memory if you decide to use this 3888 when your environment is "embedded" within U-Boot code, 3889 since then the remainder of the flash sector could be used 3890 for U-Boot code. It should be pointed out that this is 3891 STRONGLY DISCOURAGED from a robustness point of view: 3892 updating the environment in flash makes it always 3893 necessary to erase the WHOLE sector. If something goes 3894 wrong before the contents has been restored from a copy in 3895 RAM, your target system will be dead. 3896 3897 - CONFIG_ENV_ADDR_REDUND 3898 CONFIG_ENV_SIZE_REDUND 3899 3900 These settings describe a second storage area used to hold 3901 a redundant copy of the environment data, so that there is 3902 a valid backup copy in case there is a power failure during 3903 a "saveenv" operation. 3904 3905BE CAREFUL! Any changes to the flash layout, and some changes to the 3906source code will make it necessary to adapt <board>/u-boot.lds* 3907accordingly! 3908 3909 3910- CONFIG_ENV_IS_IN_NVRAM: 3911 3912 Define this if you have some non-volatile memory device 3913 (NVRAM, battery buffered SRAM) which you want to use for the 3914 environment. 3915 3916 - CONFIG_ENV_ADDR: 3917 - CONFIG_ENV_SIZE: 3918 3919 These two #defines are used to determine the memory area you 3920 want to use for environment. It is assumed that this memory 3921 can just be read and written to, without any special 3922 provision. 3923 3924BE CAREFUL! The first access to the environment happens quite early 3925in U-Boot initalization (when we try to get the setting of for the 3926console baudrate). You *MUST* have mapped your NVRAM area then, or 3927U-Boot will hang. 3928 3929Please note that even with NVRAM we still use a copy of the 3930environment in RAM: we could work on NVRAM directly, but we want to 3931keep settings there always unmodified except somebody uses "saveenv" 3932to save the current settings. 3933 3934 3935- CONFIG_ENV_IS_IN_EEPROM: 3936 3937 Use this if you have an EEPROM or similar serial access 3938 device and a driver for it. 3939 3940 - CONFIG_ENV_OFFSET: 3941 - CONFIG_ENV_SIZE: 3942 3943 These two #defines specify the offset and size of the 3944 environment area within the total memory of your EEPROM. 3945 3946 - CONFIG_SYS_I2C_EEPROM_ADDR: 3947 If defined, specified the chip address of the EEPROM device. 3948 The default address is zero. 3949 3950 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3951 If defined, the number of bits used to address bytes in a 3952 single page in the EEPROM device. A 64 byte page, for example 3953 would require six bits. 3954 3955 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3956 If defined, the number of milliseconds to delay between 3957 page writes. The default is zero milliseconds. 3958 3959 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3960 The length in bytes of the EEPROM memory array address. Note 3961 that this is NOT the chip address length! 3962 3963 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3964 EEPROM chips that implement "address overflow" are ones 3965 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3966 address and the extra bits end up in the "chip address" bit 3967 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3968 byte chips. 3969 3970 Note that we consider the length of the address field to 3971 still be one byte because the extra address bits are hidden 3972 in the chip address. 3973 3974 - CONFIG_SYS_EEPROM_SIZE: 3975 The size in bytes of the EEPROM device. 3976 3977 - CONFIG_ENV_EEPROM_IS_ON_I2C 3978 define this, if you have I2C and SPI activated, and your 3979 EEPROM, which holds the environment, is on the I2C bus. 3980 3981 - CONFIG_I2C_ENV_EEPROM_BUS 3982 if you have an Environment on an EEPROM reached over 3983 I2C muxes, you can define here, how to reach this 3984 EEPROM. For example: 3985 3986 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3987 3988 EEPROM which holds the environment, is reached over 3989 a pca9547 i2c mux with address 0x70, channel 3. 3990 3991- CONFIG_ENV_IS_IN_DATAFLASH: 3992 3993 Define this if you have a DataFlash memory device which you 3994 want to use for the environment. 3995 3996 - CONFIG_ENV_OFFSET: 3997 - CONFIG_ENV_ADDR: 3998 - CONFIG_ENV_SIZE: 3999 4000 These three #defines specify the offset and size of the 4001 environment area within the total memory of your DataFlash placed 4002 at the specified address. 4003 4004- CONFIG_ENV_IS_IN_REMOTE: 4005 4006 Define this if you have a remote memory space which you 4007 want to use for the local device's environment. 4008 4009 - CONFIG_ENV_ADDR: 4010 - CONFIG_ENV_SIZE: 4011 4012 These two #defines specify the address and size of the 4013 environment area within the remote memory space. The 4014 local device can get the environment from remote memory 4015 space by SRIO or PCIE links. 4016 4017BE CAREFUL! For some special cases, the local device can not use 4018"saveenv" command. For example, the local device will get the 4019environment stored in a remote NOR flash by SRIO or PCIE link, 4020but it can not erase, write this NOR flash by SRIO or PCIE interface. 4021 4022- CONFIG_ENV_IS_IN_NAND: 4023 4024 Define this if you have a NAND device which you want to use 4025 for the environment. 4026 4027 - CONFIG_ENV_OFFSET: 4028 - CONFIG_ENV_SIZE: 4029 4030 These two #defines specify the offset and size of the environment 4031 area within the first NAND device. CONFIG_ENV_OFFSET must be 4032 aligned to an erase block boundary. 4033 4034 - CONFIG_ENV_OFFSET_REDUND (optional): 4035 4036 This setting describes a second storage area of CONFIG_ENV_SIZE 4037 size used to hold a redundant copy of the environment data, so 4038 that there is a valid backup copy in case there is a power failure 4039 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4040 aligned to an erase block boundary. 4041 4042 - CONFIG_ENV_RANGE (optional): 4043 4044 Specifies the length of the region in which the environment 4045 can be written. This should be a multiple of the NAND device's 4046 block size. Specifying a range with more erase blocks than 4047 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4048 the range to be avoided. 4049 4050 - CONFIG_ENV_OFFSET_OOB (optional): 4051 4052 Enables support for dynamically retrieving the offset of the 4053 environment from block zero's out-of-band data. The 4054 "nand env.oob" command can be used to record this offset. 4055 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4056 using CONFIG_ENV_OFFSET_OOB. 4057 4058- CONFIG_NAND_ENV_DST 4059 4060 Defines address in RAM to which the nand_spl code should copy the 4061 environment. If redundant environment is used, it will be copied to 4062 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4063 4064- CONFIG_ENV_IS_IN_UBI: 4065 4066 Define this if you have an UBI volume that you want to use for the 4067 environment. This has the benefit of wear-leveling the environment 4068 accesses, which is important on NAND. 4069 4070 - CONFIG_ENV_UBI_PART: 4071 4072 Define this to a string that is the mtd partition containing the UBI. 4073 4074 - CONFIG_ENV_UBI_VOLUME: 4075 4076 Define this to the name of the volume that you want to store the 4077 environment in. 4078 4079 - CONFIG_ENV_UBI_VOLUME_REDUND: 4080 4081 Define this to the name of another volume to store a second copy of 4082 the environment in. This will enable redundant environments in UBI. 4083 It is assumed that both volumes are in the same MTD partition. 4084 4085 - CONFIG_UBI_SILENCE_MSG 4086 - CONFIG_UBIFS_SILENCE_MSG 4087 4088 You will probably want to define these to avoid a really noisy system 4089 when storing the env in UBI. 4090 4091- CONFIG_ENV_IS_IN_MMC: 4092 4093 Define this if you have an MMC device which you want to use for the 4094 environment. 4095 4096 - CONFIG_SYS_MMC_ENV_DEV: 4097 4098 Specifies which MMC device the environment is stored in. 4099 4100 - CONFIG_SYS_MMC_ENV_PART (optional): 4101 4102 Specifies which MMC partition the environment is stored in. If not 4103 set, defaults to partition 0, the user area. Common values might be 4104 1 (first MMC boot partition), 2 (second MMC boot partition). 4105 4106 - CONFIG_ENV_OFFSET: 4107 - CONFIG_ENV_SIZE: 4108 4109 These two #defines specify the offset and size of the environment 4110 area within the specified MMC device. 4111 4112 If offset is positive (the usual case), it is treated as relative to 4113 the start of the MMC partition. If offset is negative, it is treated 4114 as relative to the end of the MMC partition. This can be useful if 4115 your board may be fitted with different MMC devices, which have 4116 different sizes for the MMC partitions, and you always want the 4117 environment placed at the very end of the partition, to leave the 4118 maximum possible space before it, to store other data. 4119 4120 These two values are in units of bytes, but must be aligned to an 4121 MMC sector boundary. 4122 4123 - CONFIG_ENV_OFFSET_REDUND (optional): 4124 4125 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4126 hold a redundant copy of the environment data. This provides a 4127 valid backup copy in case the other copy is corrupted, e.g. due 4128 to a power failure during a "saveenv" operation. 4129 4130 This value may also be positive or negative; this is handled in the 4131 same way as CONFIG_ENV_OFFSET. 4132 4133 This value is also in units of bytes, but must also be aligned to 4134 an MMC sector boundary. 4135 4136 - CONFIG_ENV_SIZE_REDUND (optional): 4137 4138 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4139 set. If this value is set, it must be set to the same value as 4140 CONFIG_ENV_SIZE. 4141 4142- CONFIG_SYS_SPI_INIT_OFFSET 4143 4144 Defines offset to the initial SPI buffer area in DPRAM. The 4145 area is used at an early stage (ROM part) if the environment 4146 is configured to reside in the SPI EEPROM: We need a 520 byte 4147 scratch DPRAM area. It is used between the two initialization 4148 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4149 to be a good choice since it makes it far enough from the 4150 start of the data area as well as from the stack pointer. 4151 4152Please note that the environment is read-only until the monitor 4153has been relocated to RAM and a RAM copy of the environment has been 4154created; also, when using EEPROM you will have to use getenv_f() 4155until then to read environment variables. 4156 4157The environment is protected by a CRC32 checksum. Before the monitor 4158is relocated into RAM, as a result of a bad CRC you will be working 4159with the compiled-in default environment - *silently*!!! [This is 4160necessary, because the first environment variable we need is the 4161"baudrate" setting for the console - if we have a bad CRC, we don't 4162have any device yet where we could complain.] 4163 4164Note: once the monitor has been relocated, then it will complain if 4165the default environment is used; a new CRC is computed as soon as you 4166use the "saveenv" command to store a valid environment. 4167 4168- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4169 Echo the inverted Ethernet link state to the fault LED. 4170 4171 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4172 also needs to be defined. 4173 4174- CONFIG_SYS_FAULT_MII_ADDR: 4175 MII address of the PHY to check for the Ethernet link state. 4176 4177- CONFIG_NS16550_MIN_FUNCTIONS: 4178 Define this if you desire to only have use of the NS16550_init 4179 and NS16550_putc functions for the serial driver located at 4180 drivers/serial/ns16550.c. This option is useful for saving 4181 space for already greatly restricted images, including but not 4182 limited to NAND_SPL configurations. 4183 4184- CONFIG_DISPLAY_BOARDINFO 4185 Display information about the board that U-Boot is running on 4186 when U-Boot starts up. The board function checkboard() is called 4187 to do this. 4188 4189- CONFIG_DISPLAY_BOARDINFO_LATE 4190 Similar to the previous option, but display this information 4191 later, once stdio is running and output goes to the LCD, if 4192 present. 4193 4194Low Level (hardware related) configuration options: 4195--------------------------------------------------- 4196 4197- CONFIG_SYS_CACHELINE_SIZE: 4198 Cache Line Size of the CPU. 4199 4200- CONFIG_SYS_DEFAULT_IMMR: 4201 Default address of the IMMR after system reset. 4202 4203 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4204 and RPXsuper) to be able to adjust the position of 4205 the IMMR register after a reset. 4206 4207- CONFIG_SYS_CCSRBAR_DEFAULT: 4208 Default (power-on reset) physical address of CCSR on Freescale 4209 PowerPC SOCs. 4210 4211- CONFIG_SYS_CCSRBAR: 4212 Virtual address of CCSR. On a 32-bit build, this is typically 4213 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4214 4215 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4216 for cross-platform code that uses that macro instead. 4217 4218- CONFIG_SYS_CCSRBAR_PHYS: 4219 Physical address of CCSR. CCSR can be relocated to a new 4220 physical address, if desired. In this case, this macro should 4221 be set to that address. Otherwise, it should be set to the 4222 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4223 is typically relocated on 36-bit builds. It is recommended 4224 that this macro be defined via the _HIGH and _LOW macros: 4225 4226 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4227 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4228 4229- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4230 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4231 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4232 used in assembly code, so it must not contain typecasts or 4233 integer size suffixes (e.g. "ULL"). 4234 4235- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4236 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4237 used in assembly code, so it must not contain typecasts or 4238 integer size suffixes (e.g. "ULL"). 4239 4240- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4241 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4242 forced to a value that ensures that CCSR is not relocated. 4243 4244- Floppy Disk Support: 4245 CONFIG_SYS_FDC_DRIVE_NUMBER 4246 4247 the default drive number (default value 0) 4248 4249 CONFIG_SYS_ISA_IO_STRIDE 4250 4251 defines the spacing between FDC chipset registers 4252 (default value 1) 4253 4254 CONFIG_SYS_ISA_IO_OFFSET 4255 4256 defines the offset of register from address. It 4257 depends on which part of the data bus is connected to 4258 the FDC chipset. (default value 0) 4259 4260 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4261 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4262 default value. 4263 4264 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4265 fdc_hw_init() is called at the beginning of the FDC 4266 setup. fdc_hw_init() must be provided by the board 4267 source code. It is used to make hardware dependant 4268 initializations. 4269 4270- CONFIG_IDE_AHB: 4271 Most IDE controllers were designed to be connected with PCI 4272 interface. Only few of them were designed for AHB interface. 4273 When software is doing ATA command and data transfer to 4274 IDE devices through IDE-AHB controller, some additional 4275 registers accessing to these kind of IDE-AHB controller 4276 is requierd. 4277 4278- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4279 DO NOT CHANGE unless you know exactly what you're 4280 doing! (11-4) [MPC8xx/82xx systems only] 4281 4282- CONFIG_SYS_INIT_RAM_ADDR: 4283 4284 Start address of memory area that can be used for 4285 initial data and stack; please note that this must be 4286 writable memory that is working WITHOUT special 4287 initialization, i. e. you CANNOT use normal RAM which 4288 will become available only after programming the 4289 memory controller and running certain initialization 4290 sequences. 4291 4292 U-Boot uses the following memory types: 4293 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4294 - MPC824X: data cache 4295 - PPC4xx: data cache 4296 4297- CONFIG_SYS_GBL_DATA_OFFSET: 4298 4299 Offset of the initial data structure in the memory 4300 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4301 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4302 data is located at the end of the available space 4303 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4304 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4305 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4306 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4307 4308 Note: 4309 On the MPC824X (or other systems that use the data 4310 cache for initial memory) the address chosen for 4311 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4312 point to an otherwise UNUSED address space between 4313 the top of RAM and the start of the PCI space. 4314 4315- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4316 4317- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4318 4319- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4320 4321- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4322 4323- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4324 4325- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4326 4327- CONFIG_SYS_OR_TIMING_SDRAM: 4328 SDRAM timing 4329 4330- CONFIG_SYS_MAMR_PTA: 4331 periodic timer for refresh 4332 4333- CONFIG_SYS_DER: Debug Event Register (37-47) 4334 4335- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4336 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4337 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4338 CONFIG_SYS_BR1_PRELIM: 4339 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4340 4341- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4342 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4343 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4344 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4345 4346- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4347 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4348 Machine Mode Register and Memory Periodic Timer 4349 Prescaler definitions (SDRAM timing) 4350 4351- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4352 enable I2C microcode relocation patch (MPC8xx); 4353 define relocation offset in DPRAM [DSP2] 4354 4355- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4356 enable SMC microcode relocation patch (MPC8xx); 4357 define relocation offset in DPRAM [SMC1] 4358 4359- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4360 enable SPI microcode relocation patch (MPC8xx); 4361 define relocation offset in DPRAM [SCC4] 4362 4363- CONFIG_SYS_USE_OSCCLK: 4364 Use OSCM clock mode on MBX8xx board. Be careful, 4365 wrong setting might damage your board. Read 4366 doc/README.MBX before setting this variable! 4367 4368- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4369 Offset of the bootmode word in DPRAM used by post 4370 (Power On Self Tests). This definition overrides 4371 #define'd default value in commproc.h resp. 4372 cpm_8260.h. 4373 4374- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4375 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4376 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4377 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4378 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4379 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4380 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4381 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4382 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4383 4384- CONFIG_PCI_DISABLE_PCIE: 4385 Disable PCI-Express on systems where it is supported but not 4386 required. 4387 4388- CONFIG_PCI_ENUM_ONLY 4389 Only scan through and get the devices on the busses. 4390 Don't do any setup work, presumably because someone or 4391 something has already done it, and we don't need to do it 4392 a second time. Useful for platforms that are pre-booted 4393 by coreboot or similar. 4394 4395- CONFIG_PCI_INDIRECT_BRIDGE: 4396 Enable support for indirect PCI bridges. 4397 4398- CONFIG_SYS_SRIO: 4399 Chip has SRIO or not 4400 4401- CONFIG_SRIO1: 4402 Board has SRIO 1 port available 4403 4404- CONFIG_SRIO2: 4405 Board has SRIO 2 port available 4406 4407- CONFIG_SRIO_PCIE_BOOT_MASTER 4408 Board can support master function for Boot from SRIO and PCIE 4409 4410- CONFIG_SYS_SRIOn_MEM_VIRT: 4411 Virtual Address of SRIO port 'n' memory region 4412 4413- CONFIG_SYS_SRIOn_MEM_PHYS: 4414 Physical Address of SRIO port 'n' memory region 4415 4416- CONFIG_SYS_SRIOn_MEM_SIZE: 4417 Size of SRIO port 'n' memory region 4418 4419- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4420 Defined to tell the NAND controller that the NAND chip is using 4421 a 16 bit bus. 4422 Not all NAND drivers use this symbol. 4423 Example of drivers that use it: 4424 - drivers/mtd/nand/ndfc.c 4425 - drivers/mtd/nand/mxc_nand.c 4426 4427- CONFIG_SYS_NDFC_EBC0_CFG 4428 Sets the EBC0_CFG register for the NDFC. If not defined 4429 a default value will be used. 4430 4431- CONFIG_SPD_EEPROM 4432 Get DDR timing information from an I2C EEPROM. Common 4433 with pluggable memory modules such as SODIMMs 4434 4435 SPD_EEPROM_ADDRESS 4436 I2C address of the SPD EEPROM 4437 4438- CONFIG_SYS_SPD_BUS_NUM 4439 If SPD EEPROM is on an I2C bus other than the first 4440 one, specify here. Note that the value must resolve 4441 to something your driver can deal with. 4442 4443- CONFIG_SYS_DDR_RAW_TIMING 4444 Get DDR timing information from other than SPD. Common with 4445 soldered DDR chips onboard without SPD. DDR raw timing 4446 parameters are extracted from datasheet and hard-coded into 4447 header files or board specific files. 4448 4449- CONFIG_FSL_DDR_INTERACTIVE 4450 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4451 4452- CONFIG_SYS_83XX_DDR_USES_CS0 4453 Only for 83xx systems. If specified, then DDR should 4454 be configured using CS0 and CS1 instead of CS2 and CS3. 4455 4456- CONFIG_ETHER_ON_FEC[12] 4457 Define to enable FEC[12] on a 8xx series processor. 4458 4459- CONFIG_FEC[12]_PHY 4460 Define to the hardcoded PHY address which corresponds 4461 to the given FEC; i. e. 4462 #define CONFIG_FEC1_PHY 4 4463 means that the PHY with address 4 is connected to FEC1 4464 4465 When set to -1, means to probe for first available. 4466 4467- CONFIG_FEC[12]_PHY_NORXERR 4468 The PHY does not have a RXERR line (RMII only). 4469 (so program the FEC to ignore it). 4470 4471- CONFIG_RMII 4472 Enable RMII mode for all FECs. 4473 Note that this is a global option, we can't 4474 have one FEC in standard MII mode and another in RMII mode. 4475 4476- CONFIG_CRC32_VERIFY 4477 Add a verify option to the crc32 command. 4478 The syntax is: 4479 4480 => crc32 -v <address> <count> <crc32> 4481 4482 Where address/count indicate a memory area 4483 and crc32 is the correct crc32 which the 4484 area should have. 4485 4486- CONFIG_LOOPW 4487 Add the "loopw" memory command. This only takes effect if 4488 the memory commands are activated globally (CONFIG_CMD_MEM). 4489 4490- CONFIG_MX_CYCLIC 4491 Add the "mdc" and "mwc" memory commands. These are cyclic 4492 "md/mw" commands. 4493 Examples: 4494 4495 => mdc.b 10 4 500 4496 This command will print 4 bytes (10,11,12,13) each 500 ms. 4497 4498 => mwc.l 100 12345678 10 4499 This command will write 12345678 to address 100 all 10 ms. 4500 4501 This only takes effect if the memory commands are activated 4502 globally (CONFIG_CMD_MEM). 4503 4504- CONFIG_SKIP_LOWLEVEL_INIT 4505 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4506 low level initializations (like setting up the memory 4507 controller) are omitted and/or U-Boot does not 4508 relocate itself into RAM. 4509 4510 Normally this variable MUST NOT be defined. The only 4511 exception is when U-Boot is loaded (to RAM) by some 4512 other boot loader or by a debugger which performs 4513 these initializations itself. 4514 4515- CONFIG_SPL_BUILD 4516 Modifies the behaviour of start.S when compiling a loader 4517 that is executed before the actual U-Boot. E.g. when 4518 compiling a NAND SPL. 4519 4520- CONFIG_TPL_BUILD 4521 Modifies the behaviour of start.S when compiling a loader 4522 that is executed after the SPL and before the actual U-Boot. 4523 It is loaded by the SPL. 4524 4525- CONFIG_SYS_MPC85XX_NO_RESETVEC 4526 Only for 85xx systems. If this variable is specified, the section 4527 .resetvec is not kept and the section .bootpg is placed in the 4528 previous 4k of the .text section. 4529 4530- CONFIG_ARCH_MAP_SYSMEM 4531 Generally U-Boot (and in particular the md command) uses 4532 effective address. It is therefore not necessary to regard 4533 U-Boot address as virtual addresses that need to be translated 4534 to physical addresses. However, sandbox requires this, since 4535 it maintains its own little RAM buffer which contains all 4536 addressable memory. This option causes some memory accesses 4537 to be mapped through map_sysmem() / unmap_sysmem(). 4538 4539- CONFIG_USE_ARCH_MEMCPY 4540 CONFIG_USE_ARCH_MEMSET 4541 If these options are used a optimized version of memcpy/memset will 4542 be used if available. These functions may be faster under some 4543 conditions but may increase the binary size. 4544 4545- CONFIG_X86_RESET_VECTOR 4546 If defined, the x86 reset vector code is included. This is not 4547 needed when U-Boot is running from Coreboot. 4548 4549- CONFIG_SYS_MPUCLK 4550 Defines the MPU clock speed (in MHz). 4551 4552 NOTE : currently only supported on AM335x platforms. 4553 4554- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4555 Enables the RTC32K OSC on AM33xx based plattforms 4556 4557- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4558 Option to disable subpage write in NAND driver 4559 driver that uses this: 4560 drivers/mtd/nand/davinci_nand.c 4561 4562Freescale QE/FMAN Firmware Support: 4563----------------------------------- 4564 4565The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4566loading of "firmware", which is encoded in the QE firmware binary format. 4567This firmware often needs to be loaded during U-Boot booting, so macros 4568are used to identify the storage device (NOR flash, SPI, etc) and the address 4569within that device. 4570 4571- CONFIG_SYS_FMAN_FW_ADDR 4572 The address in the storage device where the FMAN microcode is located. The 4573 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4574 is also specified. 4575 4576- CONFIG_SYS_QE_FW_ADDR 4577 The address in the storage device where the QE microcode is located. The 4578 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4579 is also specified. 4580 4581- CONFIG_SYS_QE_FMAN_FW_LENGTH 4582 The maximum possible size of the firmware. The firmware binary format 4583 has a field that specifies the actual size of the firmware, but it 4584 might not be possible to read any part of the firmware unless some 4585 local storage is allocated to hold the entire firmware first. 4586 4587- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4588 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4589 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4590 virtual address in NOR flash. 4591 4592- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4593 Specifies that QE/FMAN firmware is located in NAND flash. 4594 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4595 4596- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4597 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4598 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4599 4600- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 4601 Specifies that QE/FMAN firmware is located on the primary SPI 4602 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4603 4604- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4605 Specifies that QE/FMAN firmware is located in the remote (master) 4606 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4607 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4608 window->master inbound window->master LAW->the ucode address in 4609 master's memory space. 4610 4611Building the Software: 4612====================== 4613 4614Building U-Boot has been tested in several native build environments 4615and in many different cross environments. Of course we cannot support 4616all possibly existing versions of cross development tools in all 4617(potentially obsolete) versions. In case of tool chain problems we 4618recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4619which is extensively used to build and test U-Boot. 4620 4621If you are not using a native environment, it is assumed that you 4622have GNU cross compiling tools available in your path. In this case, 4623you must set the environment variable CROSS_COMPILE in your shell. 4624Note that no changes to the Makefile or any other source files are 4625necessary. For example using the ELDK on a 4xx CPU, please enter: 4626 4627 $ CROSS_COMPILE=ppc_4xx- 4628 $ export CROSS_COMPILE 4629 4630Note: If you wish to generate Windows versions of the utilities in 4631 the tools directory you can use the MinGW toolchain 4632 (http://www.mingw.org). Set your HOST tools to the MinGW 4633 toolchain and execute 'make tools'. For example: 4634 4635 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4636 4637 Binaries such as tools/mkimage.exe will be created which can 4638 be executed on computers running Windows. 4639 4640U-Boot is intended to be simple to build. After installing the 4641sources you must configure U-Boot for one specific board type. This 4642is done by typing: 4643 4644 make NAME_config 4645 4646where "NAME_config" is the name of one of the existing configu- 4647rations; see boards.cfg for supported names. 4648 4649Note: for some board special configuration names may exist; check if 4650 additional information is available from the board vendor; for 4651 instance, the TQM823L systems are available without (standard) 4652 or with LCD support. You can select such additional "features" 4653 when choosing the configuration, i. e. 4654 4655 make TQM823L_config 4656 - will configure for a plain TQM823L, i. e. no LCD support 4657 4658 make TQM823L_LCD_config 4659 - will configure for a TQM823L with U-Boot console on LCD 4660 4661 etc. 4662 4663 4664Finally, type "make all", and you should get some working U-Boot 4665images ready for download to / installation on your system: 4666 4667- "u-boot.bin" is a raw binary image 4668- "u-boot" is an image in ELF binary format 4669- "u-boot.srec" is in Motorola S-Record format 4670 4671By default the build is performed locally and the objects are saved 4672in the source directory. One of the two methods can be used to change 4673this behavior and build U-Boot to some external directory: 4674 46751. Add O= to the make command line invocations: 4676 4677 make O=/tmp/build distclean 4678 make O=/tmp/build NAME_config 4679 make O=/tmp/build all 4680 46812. Set environment variable BUILD_DIR to point to the desired location: 4682 4683 export BUILD_DIR=/tmp/build 4684 make distclean 4685 make NAME_config 4686 make all 4687 4688Note that the command line "O=" setting overrides the BUILD_DIR environment 4689variable. 4690 4691 4692Please be aware that the Makefiles assume you are using GNU make, so 4693for instance on NetBSD you might need to use "gmake" instead of 4694native "make". 4695 4696 4697If the system board that you have is not listed, then you will need 4698to port U-Boot to your hardware platform. To do this, follow these 4699steps: 4700 47011. Add a new configuration option for your board to the toplevel 4702 "boards.cfg" file, using the existing entries as examples. 4703 Follow the instructions there to keep the boards in order. 47042. Create a new directory to hold your board specific code. Add any 4705 files you need. In your board directory, you will need at least 4706 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 47073. Create a new configuration file "include/configs/<board>.h" for 4708 your board 47093. If you're porting U-Boot to a new CPU, then also create a new 4710 directory to hold your CPU specific code. Add any files you need. 47114. Run "make <board>_config" with your new name. 47125. Type "make", and you should get a working "u-boot.srec" file 4713 to be installed on your target system. 47146. Debug and solve any problems that might arise. 4715 [Of course, this last step is much harder than it sounds.] 4716 4717 4718Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4719============================================================== 4720 4721If you have modified U-Boot sources (for instance added a new board 4722or support for new devices, a new CPU, etc.) you are expected to 4723provide feedback to the other developers. The feedback normally takes 4724the form of a "patch", i. e. a context diff against a certain (latest 4725official or latest in the git repository) version of U-Boot sources. 4726 4727But before you submit such a patch, please verify that your modifi- 4728cation did not break existing code. At least make sure that *ALL* of 4729the supported boards compile WITHOUT ANY compiler warnings. To do so, 4730just run the "MAKEALL" script, which will configure and build U-Boot 4731for ALL supported system. Be warned, this will take a while. You can 4732select which (cross) compiler to use by passing a `CROSS_COMPILE' 4733environment variable to the script, i. e. to use the ELDK cross tools 4734you can type 4735 4736 CROSS_COMPILE=ppc_8xx- MAKEALL 4737 4738or to build on a native PowerPC system you can type 4739 4740 CROSS_COMPILE=' ' MAKEALL 4741 4742When using the MAKEALL script, the default behaviour is to build 4743U-Boot in the source directory. This location can be changed by 4744setting the BUILD_DIR environment variable. Also, for each target 4745built, the MAKEALL script saves two log files (<target>.ERR and 4746<target>.MAKEALL) in the <source dir>/LOG directory. This default 4747location can be changed by setting the MAKEALL_LOGDIR environment 4748variable. For example: 4749 4750 export BUILD_DIR=/tmp/build 4751 export MAKEALL_LOGDIR=/tmp/log 4752 CROSS_COMPILE=ppc_8xx- MAKEALL 4753 4754With the above settings build objects are saved in the /tmp/build, 4755log files are saved in the /tmp/log and the source tree remains clean 4756during the whole build process. 4757 4758 4759See also "U-Boot Porting Guide" below. 4760 4761 4762Monitor Commands - Overview: 4763============================ 4764 4765go - start application at address 'addr' 4766run - run commands in an environment variable 4767bootm - boot application image from memory 4768bootp - boot image via network using BootP/TFTP protocol 4769bootz - boot zImage from memory 4770tftpboot- boot image via network using TFTP protocol 4771 and env variables "ipaddr" and "serverip" 4772 (and eventually "gatewayip") 4773tftpput - upload a file via network using TFTP protocol 4774rarpboot- boot image via network using RARP/TFTP protocol 4775diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4776loads - load S-Record file over serial line 4777loadb - load binary file over serial line (kermit mode) 4778md - memory display 4779mm - memory modify (auto-incrementing) 4780nm - memory modify (constant address) 4781mw - memory write (fill) 4782cp - memory copy 4783cmp - memory compare 4784crc32 - checksum calculation 4785i2c - I2C sub-system 4786sspi - SPI utility commands 4787base - print or set address offset 4788printenv- print environment variables 4789setenv - set environment variables 4790saveenv - save environment variables to persistent storage 4791protect - enable or disable FLASH write protection 4792erase - erase FLASH memory 4793flinfo - print FLASH memory information 4794nand - NAND memory operations (see doc/README.nand) 4795bdinfo - print Board Info structure 4796iminfo - print header information for application image 4797coninfo - print console devices and informations 4798ide - IDE sub-system 4799loop - infinite loop on address range 4800loopw - infinite write loop on address range 4801mtest - simple RAM test 4802icache - enable or disable instruction cache 4803dcache - enable or disable data cache 4804reset - Perform RESET of the CPU 4805echo - echo args to console 4806version - print monitor version 4807help - print online help 4808? - alias for 'help' 4809 4810 4811Monitor Commands - Detailed Description: 4812======================================== 4813 4814TODO. 4815 4816For now: just type "help <command>". 4817 4818 4819Environment Variables: 4820====================== 4821 4822U-Boot supports user configuration using Environment Variables which 4823can be made persistent by saving to Flash memory. 4824 4825Environment Variables are set using "setenv", printed using 4826"printenv", and saved to Flash using "saveenv". Using "setenv" 4827without a value can be used to delete a variable from the 4828environment. As long as you don't save the environment you are 4829working with an in-memory copy. In case the Flash area containing the 4830environment is erased by accident, a default environment is provided. 4831 4832Some configuration options can be set using Environment Variables. 4833 4834List of environment variables (most likely not complete): 4835 4836 baudrate - see CONFIG_BAUDRATE 4837 4838 bootdelay - see CONFIG_BOOTDELAY 4839 4840 bootcmd - see CONFIG_BOOTCOMMAND 4841 4842 bootargs - Boot arguments when booting an RTOS image 4843 4844 bootfile - Name of the image to load with TFTP 4845 4846 bootm_low - Memory range available for image processing in the bootm 4847 command can be restricted. This variable is given as 4848 a hexadecimal number and defines lowest address allowed 4849 for use by the bootm command. See also "bootm_size" 4850 environment variable. Address defined by "bootm_low" is 4851 also the base of the initial memory mapping for the Linux 4852 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4853 bootm_mapsize. 4854 4855 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4856 This variable is given as a hexadecimal number and it 4857 defines the size of the memory region starting at base 4858 address bootm_low that is accessible by the Linux kernel 4859 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4860 as the default value if it is defined, and bootm_size is 4861 used otherwise. 4862 4863 bootm_size - Memory range available for image processing in the bootm 4864 command can be restricted. This variable is given as 4865 a hexadecimal number and defines the size of the region 4866 allowed for use by the bootm command. See also "bootm_low" 4867 environment variable. 4868 4869 updatefile - Location of the software update file on a TFTP server, used 4870 by the automatic software update feature. Please refer to 4871 documentation in doc/README.update for more details. 4872 4873 autoload - if set to "no" (any string beginning with 'n'), 4874 "bootp" will just load perform a lookup of the 4875 configuration from the BOOTP server, but not try to 4876 load any image using TFTP 4877 4878 autostart - if set to "yes", an image loaded using the "bootp", 4879 "rarpboot", "tftpboot" or "diskboot" commands will 4880 be automatically started (by internally calling 4881 "bootm") 4882 4883 If set to "no", a standalone image passed to the 4884 "bootm" command will be copied to the load address 4885 (and eventually uncompressed), but NOT be started. 4886 This can be used to load and uncompress arbitrary 4887 data. 4888 4889 fdt_high - if set this restricts the maximum address that the 4890 flattened device tree will be copied into upon boot. 4891 For example, if you have a system with 1 GB memory 4892 at physical address 0x10000000, while Linux kernel 4893 only recognizes the first 704 MB as low memory, you 4894 may need to set fdt_high as 0x3C000000 to have the 4895 device tree blob be copied to the maximum address 4896 of the 704 MB low memory, so that Linux kernel can 4897 access it during the boot procedure. 4898 4899 If this is set to the special value 0xFFFFFFFF then 4900 the fdt will not be copied at all on boot. For this 4901 to work it must reside in writable memory, have 4902 sufficient padding on the end of it for u-boot to 4903 add the information it needs into it, and the memory 4904 must be accessible by the kernel. 4905 4906 fdtcontroladdr- if set this is the address of the control flattened 4907 device tree used by U-Boot when CONFIG_OF_CONTROL is 4908 defined. 4909 4910 i2cfast - (PPC405GP|PPC405EP only) 4911 if set to 'y' configures Linux I2C driver for fast 4912 mode (400kHZ). This environment variable is used in 4913 initialization code. So, for changes to be effective 4914 it must be saved and board must be reset. 4915 4916 initrd_high - restrict positioning of initrd images: 4917 If this variable is not set, initrd images will be 4918 copied to the highest possible address in RAM; this 4919 is usually what you want since it allows for 4920 maximum initrd size. If for some reason you want to 4921 make sure that the initrd image is loaded below the 4922 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4923 variable to a value of "no" or "off" or "0". 4924 Alternatively, you can set it to a maximum upper 4925 address to use (U-Boot will still check that it 4926 does not overwrite the U-Boot stack and data). 4927 4928 For instance, when you have a system with 16 MB 4929 RAM, and want to reserve 4 MB from use by Linux, 4930 you can do this by adding "mem=12M" to the value of 4931 the "bootargs" variable. However, now you must make 4932 sure that the initrd image is placed in the first 4933 12 MB as well - this can be done with 4934 4935 setenv initrd_high 00c00000 4936 4937 If you set initrd_high to 0xFFFFFFFF, this is an 4938 indication to U-Boot that all addresses are legal 4939 for the Linux kernel, including addresses in flash 4940 memory. In this case U-Boot will NOT COPY the 4941 ramdisk at all. This may be useful to reduce the 4942 boot time on your system, but requires that this 4943 feature is supported by your Linux kernel. 4944 4945 ipaddr - IP address; needed for tftpboot command 4946 4947 loadaddr - Default load address for commands like "bootp", 4948 "rarpboot", "tftpboot", "loadb" or "diskboot" 4949 4950 loads_echo - see CONFIG_LOADS_ECHO 4951 4952 serverip - TFTP server IP address; needed for tftpboot command 4953 4954 bootretry - see CONFIG_BOOT_RETRY_TIME 4955 4956 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4957 4958 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4959 4960 ethprime - controls which interface is used first. 4961 4962 ethact - controls which interface is currently active. 4963 For example you can do the following 4964 4965 => setenv ethact FEC 4966 => ping 192.168.0.1 # traffic sent on FEC 4967 => setenv ethact SCC 4968 => ping 10.0.0.1 # traffic sent on SCC 4969 4970 ethrotate - When set to "no" U-Boot does not go through all 4971 available network interfaces. 4972 It just stays at the currently selected interface. 4973 4974 netretry - When set to "no" each network operation will 4975 either succeed or fail without retrying. 4976 When set to "once" the network operation will 4977 fail when all the available network interfaces 4978 are tried once without success. 4979 Useful on scripts which control the retry operation 4980 themselves. 4981 4982 npe_ucode - set load address for the NPE microcode 4983 4984 silent_linux - If set then linux will be told to boot silently, by 4985 changing the console to be empty. If "yes" it will be 4986 made silent. If "no" it will not be made silent. If 4987 unset, then it will be made silent if the U-Boot console 4988 is silent. 4989 4990 tftpsrcport - If this is set, the value is used for TFTP's 4991 UDP source port. 4992 4993 tftpdstport - If this is set, the value is used for TFTP's UDP 4994 destination port instead of the Well Know Port 69. 4995 4996 tftpblocksize - Block size to use for TFTP transfers; if not set, 4997 we use the TFTP server's default block size 4998 4999 tftptimeout - Retransmission timeout for TFTP packets (in milli- 5000 seconds, minimum value is 1000 = 1 second). Defines 5001 when a packet is considered to be lost so it has to 5002 be retransmitted. The default is 5000 = 5 seconds. 5003 Lowering this value may make downloads succeed 5004 faster in networks with high packet loss rates or 5005 with unreliable TFTP servers. 5006 5007 vlan - When set to a value < 4095 the traffic over 5008 Ethernet is encapsulated/received over 802.1q 5009 VLAN tagged frames. 5010 5011The following image location variables contain the location of images 5012used in booting. The "Image" column gives the role of the image and is 5013not an environment variable name. The other columns are environment 5014variable names. "File Name" gives the name of the file on a TFTP 5015server, "RAM Address" gives the location in RAM the image will be 5016loaded to, and "Flash Location" gives the image's address in NOR 5017flash or offset in NAND flash. 5018 5019*Note* - these variables don't have to be defined for all boards, some 5020boards currenlty use other variables for these purposes, and some 5021boards use these variables for other purposes. 5022 5023Image File Name RAM Address Flash Location 5024----- --------- ----------- -------------- 5025u-boot u-boot u-boot_addr_r u-boot_addr 5026Linux kernel bootfile kernel_addr_r kernel_addr 5027device tree blob fdtfile fdt_addr_r fdt_addr 5028ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5029 5030The following environment variables may be used and automatically 5031updated by the network boot commands ("bootp" and "rarpboot"), 5032depending the information provided by your boot server: 5033 5034 bootfile - see above 5035 dnsip - IP address of your Domain Name Server 5036 dnsip2 - IP address of your secondary Domain Name Server 5037 gatewayip - IP address of the Gateway (Router) to use 5038 hostname - Target hostname 5039 ipaddr - see above 5040 netmask - Subnet Mask 5041 rootpath - Pathname of the root filesystem on the NFS server 5042 serverip - see above 5043 5044 5045There are two special Environment Variables: 5046 5047 serial# - contains hardware identification information such 5048 as type string and/or serial number 5049 ethaddr - Ethernet address 5050 5051These variables can be set only once (usually during manufacturing of 5052the board). U-Boot refuses to delete or overwrite these variables 5053once they have been set once. 5054 5055 5056Further special Environment Variables: 5057 5058 ver - Contains the U-Boot version string as printed 5059 with the "version" command. This variable is 5060 readonly (see CONFIG_VERSION_VARIABLE). 5061 5062 5063Please note that changes to some configuration parameters may take 5064only effect after the next boot (yes, that's just like Windoze :-). 5065 5066 5067Callback functions for environment variables: 5068--------------------------------------------- 5069 5070For some environment variables, the behavior of u-boot needs to change 5071when their values are changed. This functionailty allows functions to 5072be associated with arbitrary variables. On creation, overwrite, or 5073deletion, the callback will provide the opportunity for some side 5074effect to happen or for the change to be rejected. 5075 5076The callbacks are named and associated with a function using the 5077U_BOOT_ENV_CALLBACK macro in your board or driver code. 5078 5079These callbacks are associated with variables in one of two ways. The 5080static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5081in the board configuration to a string that defines a list of 5082associations. The list must be in the following format: 5083 5084 entry = variable_name[:callback_name] 5085 list = entry[,list] 5086 5087If the callback name is not specified, then the callback is deleted. 5088Spaces are also allowed anywhere in the list. 5089 5090Callbacks can also be associated by defining the ".callbacks" variable 5091with the same list format above. Any association in ".callbacks" will 5092override any association in the static list. You can define 5093CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5094".callbacks" envirnoment variable in the default or embedded environment. 5095 5096 5097Command Line Parsing: 5098===================== 5099 5100There are two different command line parsers available with U-Boot: 5101the old "simple" one, and the much more powerful "hush" shell: 5102 5103Old, simple command line parser: 5104-------------------------------- 5105 5106- supports environment variables (through setenv / saveenv commands) 5107- several commands on one line, separated by ';' 5108- variable substitution using "... ${name} ..." syntax 5109- special characters ('$', ';') can be escaped by prefixing with '\', 5110 for example: 5111 setenv bootcmd bootm \${address} 5112- You can also escape text by enclosing in single apostrophes, for example: 5113 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5114 5115Hush shell: 5116----------- 5117 5118- similar to Bourne shell, with control structures like 5119 if...then...else...fi, for...do...done; while...do...done, 5120 until...do...done, ... 5121- supports environment ("global") variables (through setenv / saveenv 5122 commands) and local shell variables (through standard shell syntax 5123 "name=value"); only environment variables can be used with "run" 5124 command 5125 5126General rules: 5127-------------- 5128 5129(1) If a command line (or an environment variable executed by a "run" 5130 command) contains several commands separated by semicolon, and 5131 one of these commands fails, then the remaining commands will be 5132 executed anyway. 5133 5134(2) If you execute several variables with one call to run (i. e. 5135 calling run with a list of variables as arguments), any failing 5136 command will cause "run" to terminate, i. e. the remaining 5137 variables are not executed. 5138 5139Note for Redundant Ethernet Interfaces: 5140======================================= 5141 5142Some boards come with redundant Ethernet interfaces; U-Boot supports 5143such configurations and is capable of automatic selection of a 5144"working" interface when needed. MAC assignment works as follows: 5145 5146Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5147MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5148"eth1addr" (=>eth1), "eth2addr", ... 5149 5150If the network interface stores some valid MAC address (for instance 5151in SROM), this is used as default address if there is NO correspon- 5152ding setting in the environment; if the corresponding environment 5153variable is set, this overrides the settings in the card; that means: 5154 5155o If the SROM has a valid MAC address, and there is no address in the 5156 environment, the SROM's address is used. 5157 5158o If there is no valid address in the SROM, and a definition in the 5159 environment exists, then the value from the environment variable is 5160 used. 5161 5162o If both the SROM and the environment contain a MAC address, and 5163 both addresses are the same, this MAC address is used. 5164 5165o If both the SROM and the environment contain a MAC address, and the 5166 addresses differ, the value from the environment is used and a 5167 warning is printed. 5168 5169o If neither SROM nor the environment contain a MAC address, an error 5170 is raised. 5171 5172If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5173will be programmed into hardware as part of the initialization process. This 5174may be skipped by setting the appropriate 'ethmacskip' environment variable. 5175The naming convention is as follows: 5176"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5177 5178Image Formats: 5179============== 5180 5181U-Boot is capable of booting (and performing other auxiliary operations on) 5182images in two formats: 5183 5184New uImage format (FIT) 5185----------------------- 5186 5187Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5188to Flattened Device Tree). It allows the use of images with multiple 5189components (several kernels, ramdisks, etc.), with contents protected by 5190SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5191 5192 5193Old uImage format 5194----------------- 5195 5196Old image format is based on binary files which can be basically anything, 5197preceded by a special header; see the definitions in include/image.h for 5198details; basically, the header defines the following image properties: 5199 5200* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5201 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5202 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5203 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5204 INTEGRITY). 5205* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5206 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5207 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5208* Compression Type (uncompressed, gzip, bzip2) 5209* Load Address 5210* Entry Point 5211* Image Name 5212* Image Timestamp 5213 5214The header is marked by a special Magic Number, and both the header 5215and the data portions of the image are secured against corruption by 5216CRC32 checksums. 5217 5218 5219Linux Support: 5220============== 5221 5222Although U-Boot should support any OS or standalone application 5223easily, the main focus has always been on Linux during the design of 5224U-Boot. 5225 5226U-Boot includes many features that so far have been part of some 5227special "boot loader" code within the Linux kernel. Also, any 5228"initrd" images to be used are no longer part of one big Linux image; 5229instead, kernel and "initrd" are separate images. This implementation 5230serves several purposes: 5231 5232- the same features can be used for other OS or standalone 5233 applications (for instance: using compressed images to reduce the 5234 Flash memory footprint) 5235 5236- it becomes much easier to port new Linux kernel versions because 5237 lots of low-level, hardware dependent stuff are done by U-Boot 5238 5239- the same Linux kernel image can now be used with different "initrd" 5240 images; of course this also means that different kernel images can 5241 be run with the same "initrd". This makes testing easier (you don't 5242 have to build a new "zImage.initrd" Linux image when you just 5243 change a file in your "initrd"). Also, a field-upgrade of the 5244 software is easier now. 5245 5246 5247Linux HOWTO: 5248============ 5249 5250Porting Linux to U-Boot based systems: 5251--------------------------------------- 5252 5253U-Boot cannot save you from doing all the necessary modifications to 5254configure the Linux device drivers for use with your target hardware 5255(no, we don't intend to provide a full virtual machine interface to 5256Linux :-). 5257 5258But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5259 5260Just make sure your machine specific header file (for instance 5261include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5262Information structure as we define in include/asm-<arch>/u-boot.h, 5263and make sure that your definition of IMAP_ADDR uses the same value 5264as your U-Boot configuration in CONFIG_SYS_IMMR. 5265 5266 5267Configuring the Linux kernel: 5268----------------------------- 5269 5270No specific requirements for U-Boot. Make sure you have some root 5271device (initial ramdisk, NFS) for your target system. 5272 5273 5274Building a Linux Image: 5275----------------------- 5276 5277With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5278not used. If you use recent kernel source, a new build target 5279"uImage" will exist which automatically builds an image usable by 5280U-Boot. Most older kernels also have support for a "pImage" target, 5281which was introduced for our predecessor project PPCBoot and uses a 5282100% compatible format. 5283 5284Example: 5285 5286 make TQM850L_config 5287 make oldconfig 5288 make dep 5289 make uImage 5290 5291The "uImage" build target uses a special tool (in 'tools/mkimage') to 5292encapsulate a compressed Linux kernel image with header information, 5293CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5294 5295* build a standard "vmlinux" kernel image (in ELF binary format): 5296 5297* convert the kernel into a raw binary image: 5298 5299 ${CROSS_COMPILE}-objcopy -O binary \ 5300 -R .note -R .comment \ 5301 -S vmlinux linux.bin 5302 5303* compress the binary image: 5304 5305 gzip -9 linux.bin 5306 5307* package compressed binary image for U-Boot: 5308 5309 mkimage -A ppc -O linux -T kernel -C gzip \ 5310 -a 0 -e 0 -n "Linux Kernel Image" \ 5311 -d linux.bin.gz uImage 5312 5313 5314The "mkimage" tool can also be used to create ramdisk images for use 5315with U-Boot, either separated from the Linux kernel image, or 5316combined into one file. "mkimage" encapsulates the images with a 64 5317byte header containing information about target architecture, 5318operating system, image type, compression method, entry points, time 5319stamp, CRC32 checksums, etc. 5320 5321"mkimage" can be called in two ways: to verify existing images and 5322print the header information, or to build new images. 5323 5324In the first form (with "-l" option) mkimage lists the information 5325contained in the header of an existing U-Boot image; this includes 5326checksum verification: 5327 5328 tools/mkimage -l image 5329 -l ==> list image header information 5330 5331The second form (with "-d" option) is used to build a U-Boot image 5332from a "data file" which is used as image payload: 5333 5334 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5335 -n name -d data_file image 5336 -A ==> set architecture to 'arch' 5337 -O ==> set operating system to 'os' 5338 -T ==> set image type to 'type' 5339 -C ==> set compression type 'comp' 5340 -a ==> set load address to 'addr' (hex) 5341 -e ==> set entry point to 'ep' (hex) 5342 -n ==> set image name to 'name' 5343 -d ==> use image data from 'datafile' 5344 5345Right now, all Linux kernels for PowerPC systems use the same load 5346address (0x00000000), but the entry point address depends on the 5347kernel version: 5348 5349- 2.2.x kernels have the entry point at 0x0000000C, 5350- 2.3.x and later kernels have the entry point at 0x00000000. 5351 5352So a typical call to build a U-Boot image would read: 5353 5354 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5355 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5356 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5357 > examples/uImage.TQM850L 5358 Image Name: 2.4.4 kernel for TQM850L 5359 Created: Wed Jul 19 02:34:59 2000 5360 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5361 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5362 Load Address: 0x00000000 5363 Entry Point: 0x00000000 5364 5365To verify the contents of the image (or check for corruption): 5366 5367 -> tools/mkimage -l examples/uImage.TQM850L 5368 Image Name: 2.4.4 kernel for TQM850L 5369 Created: Wed Jul 19 02:34:59 2000 5370 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5371 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5372 Load Address: 0x00000000 5373 Entry Point: 0x00000000 5374 5375NOTE: for embedded systems where boot time is critical you can trade 5376speed for memory and install an UNCOMPRESSED image instead: this 5377needs more space in Flash, but boots much faster since it does not 5378need to be uncompressed: 5379 5380 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5381 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5382 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5383 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5384 > examples/uImage.TQM850L-uncompressed 5385 Image Name: 2.4.4 kernel for TQM850L 5386 Created: Wed Jul 19 02:34:59 2000 5387 Image Type: PowerPC Linux Kernel Image (uncompressed) 5388 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5389 Load Address: 0x00000000 5390 Entry Point: 0x00000000 5391 5392 5393Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5394when your kernel is intended to use an initial ramdisk: 5395 5396 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5397 > -A ppc -O linux -T ramdisk -C gzip \ 5398 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5399 Image Name: Simple Ramdisk Image 5400 Created: Wed Jan 12 14:01:50 2000 5401 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5402 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5403 Load Address: 0x00000000 5404 Entry Point: 0x00000000 5405 5406The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5407option performs the converse operation of the mkimage's second form (the "-d" 5408option). Given an image built by mkimage, the dumpimage extracts a "data file" 5409from the image: 5410 5411 tools/dumpimage -i image -p position data_file 5412 -i ==> extract from the 'image' a specific 'data_file', \ 5413 indexed by 'position' 5414 5415 5416Installing a Linux Image: 5417------------------------- 5418 5419To downloading a U-Boot image over the serial (console) interface, 5420you must convert the image to S-Record format: 5421 5422 objcopy -I binary -O srec examples/image examples/image.srec 5423 5424The 'objcopy' does not understand the information in the U-Boot 5425image header, so the resulting S-Record file will be relative to 5426address 0x00000000. To load it to a given address, you need to 5427specify the target address as 'offset' parameter with the 'loads' 5428command. 5429 5430Example: install the image to address 0x40100000 (which on the 5431TQM8xxL is in the first Flash bank): 5432 5433 => erase 40100000 401FFFFF 5434 5435 .......... done 5436 Erased 8 sectors 5437 5438 => loads 40100000 5439 ## Ready for S-Record download ... 5440 ~>examples/image.srec 5441 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5442 ... 5443 15989 15990 15991 15992 5444 [file transfer complete] 5445 [connected] 5446 ## Start Addr = 0x00000000 5447 5448 5449You can check the success of the download using the 'iminfo' command; 5450this includes a checksum verification so you can be sure no data 5451corruption happened: 5452 5453 => imi 40100000 5454 5455 ## Checking Image at 40100000 ... 5456 Image Name: 2.2.13 for initrd on TQM850L 5457 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5458 Data Size: 335725 Bytes = 327 kB = 0 MB 5459 Load Address: 00000000 5460 Entry Point: 0000000c 5461 Verifying Checksum ... OK 5462 5463 5464Boot Linux: 5465----------- 5466 5467The "bootm" command is used to boot an application that is stored in 5468memory (RAM or Flash). In case of a Linux kernel image, the contents 5469of the "bootargs" environment variable is passed to the kernel as 5470parameters. You can check and modify this variable using the 5471"printenv" and "setenv" commands: 5472 5473 5474 => printenv bootargs 5475 bootargs=root=/dev/ram 5476 5477 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5478 5479 => printenv bootargs 5480 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5481 5482 => bootm 40020000 5483 ## Booting Linux kernel at 40020000 ... 5484 Image Name: 2.2.13 for NFS on TQM850L 5485 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5486 Data Size: 381681 Bytes = 372 kB = 0 MB 5487 Load Address: 00000000 5488 Entry Point: 0000000c 5489 Verifying Checksum ... OK 5490 Uncompressing Kernel Image ... OK 5491 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 5492 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5493 time_init: decrementer frequency = 187500000/60 5494 Calibrating delay loop... 49.77 BogoMIPS 5495 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5496 ... 5497 5498If you want to boot a Linux kernel with initial RAM disk, you pass 5499the memory addresses of both the kernel and the initrd image (PPBCOOT 5500format!) to the "bootm" command: 5501 5502 => imi 40100000 40200000 5503 5504 ## Checking Image at 40100000 ... 5505 Image Name: 2.2.13 for initrd on TQM850L 5506 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5507 Data Size: 335725 Bytes = 327 kB = 0 MB 5508 Load Address: 00000000 5509 Entry Point: 0000000c 5510 Verifying Checksum ... OK 5511 5512 ## Checking Image at 40200000 ... 5513 Image Name: Simple Ramdisk Image 5514 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5515 Data Size: 566530 Bytes = 553 kB = 0 MB 5516 Load Address: 00000000 5517 Entry Point: 00000000 5518 Verifying Checksum ... OK 5519 5520 => bootm 40100000 40200000 5521 ## Booting Linux kernel at 40100000 ... 5522 Image Name: 2.2.13 for initrd on TQM850L 5523 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5524 Data Size: 335725 Bytes = 327 kB = 0 MB 5525 Load Address: 00000000 5526 Entry Point: 0000000c 5527 Verifying Checksum ... OK 5528 Uncompressing Kernel Image ... OK 5529 ## Loading RAMDisk Image at 40200000 ... 5530 Image Name: Simple Ramdisk Image 5531 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5532 Data Size: 566530 Bytes = 553 kB = 0 MB 5533 Load Address: 00000000 5534 Entry Point: 00000000 5535 Verifying Checksum ... OK 5536 Loading Ramdisk ... OK 5537 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 5538 Boot arguments: root=/dev/ram 5539 time_init: decrementer frequency = 187500000/60 5540 Calibrating delay loop... 49.77 BogoMIPS 5541 ... 5542 RAMDISK: Compressed image found at block 0 5543 VFS: Mounted root (ext2 filesystem). 5544 5545 bash# 5546 5547Boot Linux and pass a flat device tree: 5548----------- 5549 5550First, U-Boot must be compiled with the appropriate defines. See the section 5551titled "Linux Kernel Interface" above for a more in depth explanation. The 5552following is an example of how to start a kernel and pass an updated 5553flat device tree: 5554 5555=> print oftaddr 5556oftaddr=0x300000 5557=> print oft 5558oft=oftrees/mpc8540ads.dtb 5559=> tftp $oftaddr $oft 5560Speed: 1000, full duplex 5561Using TSEC0 device 5562TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5563Filename 'oftrees/mpc8540ads.dtb'. 5564Load address: 0x300000 5565Loading: # 5566done 5567Bytes transferred = 4106 (100a hex) 5568=> tftp $loadaddr $bootfile 5569Speed: 1000, full duplex 5570Using TSEC0 device 5571TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5572Filename 'uImage'. 5573Load address: 0x200000 5574Loading:############ 5575done 5576Bytes transferred = 1029407 (fb51f hex) 5577=> print loadaddr 5578loadaddr=200000 5579=> print oftaddr 5580oftaddr=0x300000 5581=> bootm $loadaddr - $oftaddr 5582## Booting image at 00200000 ... 5583 Image Name: Linux-2.6.17-dirty 5584 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5585 Data Size: 1029343 Bytes = 1005.2 kB 5586 Load Address: 00000000 5587 Entry Point: 00000000 5588 Verifying Checksum ... OK 5589 Uncompressing Kernel Image ... OK 5590Booting using flat device tree at 0x300000 5591Using MPC85xx ADS machine description 5592Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5593[snip] 5594 5595 5596More About U-Boot Image Types: 5597------------------------------ 5598 5599U-Boot supports the following image types: 5600 5601 "Standalone Programs" are directly runnable in the environment 5602 provided by U-Boot; it is expected that (if they behave 5603 well) you can continue to work in U-Boot after return from 5604 the Standalone Program. 5605 "OS Kernel Images" are usually images of some Embedded OS which 5606 will take over control completely. Usually these programs 5607 will install their own set of exception handlers, device 5608 drivers, set up the MMU, etc. - this means, that you cannot 5609 expect to re-enter U-Boot except by resetting the CPU. 5610 "RAMDisk Images" are more or less just data blocks, and their 5611 parameters (address, size) are passed to an OS kernel that is 5612 being started. 5613 "Multi-File Images" contain several images, typically an OS 5614 (Linux) kernel image and one or more data images like 5615 RAMDisks. This construct is useful for instance when you want 5616 to boot over the network using BOOTP etc., where the boot 5617 server provides just a single image file, but you want to get 5618 for instance an OS kernel and a RAMDisk image. 5619 5620 "Multi-File Images" start with a list of image sizes, each 5621 image size (in bytes) specified by an "uint32_t" in network 5622 byte order. This list is terminated by an "(uint32_t)0". 5623 Immediately after the terminating 0 follow the images, one by 5624 one, all aligned on "uint32_t" boundaries (size rounded up to 5625 a multiple of 4 bytes). 5626 5627 "Firmware Images" are binary images containing firmware (like 5628 U-Boot or FPGA images) which usually will be programmed to 5629 flash memory. 5630 5631 "Script files" are command sequences that will be executed by 5632 U-Boot's command interpreter; this feature is especially 5633 useful when you configure U-Boot to use a real shell (hush) 5634 as command interpreter. 5635 5636Booting the Linux zImage: 5637------------------------- 5638 5639On some platforms, it's possible to boot Linux zImage. This is done 5640using the "bootz" command. The syntax of "bootz" command is the same 5641as the syntax of "bootm" command. 5642 5643Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5644kernel with raw initrd images. The syntax is slightly different, the 5645address of the initrd must be augmented by it's size, in the following 5646format: "<initrd addres>:<initrd size>". 5647 5648 5649Standalone HOWTO: 5650================= 5651 5652One of the features of U-Boot is that you can dynamically load and 5653run "standalone" applications, which can use some resources of 5654U-Boot like console I/O functions or interrupt services. 5655 5656Two simple examples are included with the sources: 5657 5658"Hello World" Demo: 5659------------------- 5660 5661'examples/hello_world.c' contains a small "Hello World" Demo 5662application; it is automatically compiled when you build U-Boot. 5663It's configured to run at address 0x00040004, so you can play with it 5664like that: 5665 5666 => loads 5667 ## Ready for S-Record download ... 5668 ~>examples/hello_world.srec 5669 1 2 3 4 5 6 7 8 9 10 11 ... 5670 [file transfer complete] 5671 [connected] 5672 ## Start Addr = 0x00040004 5673 5674 => go 40004 Hello World! This is a test. 5675 ## Starting application at 0x00040004 ... 5676 Hello World 5677 argc = 7 5678 argv[0] = "40004" 5679 argv[1] = "Hello" 5680 argv[2] = "World!" 5681 argv[3] = "This" 5682 argv[4] = "is" 5683 argv[5] = "a" 5684 argv[6] = "test." 5685 argv[7] = "<NULL>" 5686 Hit any key to exit ... 5687 5688 ## Application terminated, rc = 0x0 5689 5690Another example, which demonstrates how to register a CPM interrupt 5691handler with the U-Boot code, can be found in 'examples/timer.c'. 5692Here, a CPM timer is set up to generate an interrupt every second. 5693The interrupt service routine is trivial, just printing a '.' 5694character, but this is just a demo program. The application can be 5695controlled by the following keys: 5696 5697 ? - print current values og the CPM Timer registers 5698 b - enable interrupts and start timer 5699 e - stop timer and disable interrupts 5700 q - quit application 5701 5702 => loads 5703 ## Ready for S-Record download ... 5704 ~>examples/timer.srec 5705 1 2 3 4 5 6 7 8 9 10 11 ... 5706 [file transfer complete] 5707 [connected] 5708 ## Start Addr = 0x00040004 5709 5710 => go 40004 5711 ## Starting application at 0x00040004 ... 5712 TIMERS=0xfff00980 5713 Using timer 1 5714 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5715 5716Hit 'b': 5717 [q, b, e, ?] Set interval 1000000 us 5718 Enabling timer 5719Hit '?': 5720 [q, b, e, ?] ........ 5721 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5722Hit '?': 5723 [q, b, e, ?] . 5724 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5725Hit '?': 5726 [q, b, e, ?] . 5727 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5728Hit '?': 5729 [q, b, e, ?] . 5730 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5731Hit 'e': 5732 [q, b, e, ?] ...Stopping timer 5733Hit 'q': 5734 [q, b, e, ?] ## Application terminated, rc = 0x0 5735 5736 5737Minicom warning: 5738================ 5739 5740Over time, many people have reported problems when trying to use the 5741"minicom" terminal emulation program for serial download. I (wd) 5742consider minicom to be broken, and recommend not to use it. Under 5743Unix, I recommend to use C-Kermit for general purpose use (and 5744especially for kermit binary protocol download ("loadb" command), and 5745use "cu" for S-Record download ("loads" command). See 5746http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5747for help with kermit. 5748 5749 5750Nevertheless, if you absolutely want to use it try adding this 5751configuration to your "File transfer protocols" section: 5752 5753 Name Program Name U/D FullScr IO-Red. Multi 5754 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5755 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5756 5757 5758NetBSD Notes: 5759============= 5760 5761Starting at version 0.9.2, U-Boot supports NetBSD both as host 5762(build U-Boot) and target system (boots NetBSD/mpc8xx). 5763 5764Building requires a cross environment; it is known to work on 5765NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5766need gmake since the Makefiles are not compatible with BSD make). 5767Note that the cross-powerpc package does not install include files; 5768attempting to build U-Boot will fail because <machine/ansi.h> is 5769missing. This file has to be installed and patched manually: 5770 5771 # cd /usr/pkg/cross/powerpc-netbsd/include 5772 # mkdir powerpc 5773 # ln -s powerpc machine 5774 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5775 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5776 5777Native builds *don't* work due to incompatibilities between native 5778and U-Boot include files. 5779 5780Booting assumes that (the first part of) the image booted is a 5781stage-2 loader which in turn loads and then invokes the kernel 5782proper. Loader sources will eventually appear in the NetBSD source 5783tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5784meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5785 5786 5787Implementation Internals: 5788========================= 5789 5790The following is not intended to be a complete description of every 5791implementation detail. However, it should help to understand the 5792inner workings of U-Boot and make it easier to port it to custom 5793hardware. 5794 5795 5796Initial Stack, Global Data: 5797--------------------------- 5798 5799The implementation of U-Boot is complicated by the fact that U-Boot 5800starts running out of ROM (flash memory), usually without access to 5801system RAM (because the memory controller is not initialized yet). 5802This means that we don't have writable Data or BSS segments, and BSS 5803is not initialized as zero. To be able to get a C environment working 5804at all, we have to allocate at least a minimal stack. Implementation 5805options for this are defined and restricted by the CPU used: Some CPU 5806models provide on-chip memory (like the IMMR area on MPC8xx and 5807MPC826x processors), on others (parts of) the data cache can be 5808locked as (mis-) used as memory, etc. 5809 5810 Chris Hallinan posted a good summary of these issues to the 5811 U-Boot mailing list: 5812 5813 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5814 From: "Chris Hallinan" <clh@net1plus.com> 5815 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5816 ... 5817 5818 Correct me if I'm wrong, folks, but the way I understand it 5819 is this: Using DCACHE as initial RAM for Stack, etc, does not 5820 require any physical RAM backing up the cache. The cleverness 5821 is that the cache is being used as a temporary supply of 5822 necessary storage before the SDRAM controller is setup. It's 5823 beyond the scope of this list to explain the details, but you 5824 can see how this works by studying the cache architecture and 5825 operation in the architecture and processor-specific manuals. 5826 5827 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5828 is another option for the system designer to use as an 5829 initial stack/RAM area prior to SDRAM being available. Either 5830 option should work for you. Using CS 4 should be fine if your 5831 board designers haven't used it for something that would 5832 cause you grief during the initial boot! It is frequently not 5833 used. 5834 5835 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5836 with your processor/board/system design. The default value 5837 you will find in any recent u-boot distribution in 5838 walnut.h should work for you. I'd set it to a value larger 5839 than your SDRAM module. If you have a 64MB SDRAM module, set 5840 it above 400_0000. Just make sure your board has no resources 5841 that are supposed to respond to that address! That code in 5842 start.S has been around a while and should work as is when 5843 you get the config right. 5844 5845 -Chris Hallinan 5846 DS4.COM, Inc. 5847 5848It is essential to remember this, since it has some impact on the C 5849code for the initialization procedures: 5850 5851* Initialized global data (data segment) is read-only. Do not attempt 5852 to write it. 5853 5854* Do not use any uninitialized global data (or implicitely initialized 5855 as zero data - BSS segment) at all - this is undefined, initiali- 5856 zation is performed later (when relocating to RAM). 5857 5858* Stack space is very limited. Avoid big data buffers or things like 5859 that. 5860 5861Having only the stack as writable memory limits means we cannot use 5862normal global data to share information beween the code. But it 5863turned out that the implementation of U-Boot can be greatly 5864simplified by making a global data structure (gd_t) available to all 5865functions. We could pass a pointer to this data as argument to _all_ 5866functions, but this would bloat the code. Instead we use a feature of 5867the GCC compiler (Global Register Variables) to share the data: we 5868place a pointer (gd) to the global data into a register which we 5869reserve for this purpose. 5870 5871When choosing a register for such a purpose we are restricted by the 5872relevant (E)ABI specifications for the current architecture, and by 5873GCC's implementation. 5874 5875For PowerPC, the following registers have specific use: 5876 R1: stack pointer 5877 R2: reserved for system use 5878 R3-R4: parameter passing and return values 5879 R5-R10: parameter passing 5880 R13: small data area pointer 5881 R30: GOT pointer 5882 R31: frame pointer 5883 5884 (U-Boot also uses R12 as internal GOT pointer. r12 5885 is a volatile register so r12 needs to be reset when 5886 going back and forth between asm and C) 5887 5888 ==> U-Boot will use R2 to hold a pointer to the global data 5889 5890 Note: on PPC, we could use a static initializer (since the 5891 address of the global data structure is known at compile time), 5892 but it turned out that reserving a register results in somewhat 5893 smaller code - although the code savings are not that big (on 5894 average for all boards 752 bytes for the whole U-Boot image, 5895 624 text + 127 data). 5896 5897On Blackfin, the normal C ABI (except for P3) is followed as documented here: 5898 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 5899 5900 ==> U-Boot will use P3 to hold a pointer to the global data 5901 5902On ARM, the following registers are used: 5903 5904 R0: function argument word/integer result 5905 R1-R3: function argument word 5906 R9: platform specific 5907 R10: stack limit (used only if stack checking is enabled) 5908 R11: argument (frame) pointer 5909 R12: temporary workspace 5910 R13: stack pointer 5911 R14: link register 5912 R15: program counter 5913 5914 ==> U-Boot will use R9 to hold a pointer to the global data 5915 5916 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5917 5918On Nios II, the ABI is documented here: 5919 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5920 5921 ==> U-Boot will use gp to hold a pointer to the global data 5922 5923 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5924 to access small data sections, so gp is free. 5925 5926On NDS32, the following registers are used: 5927 5928 R0-R1: argument/return 5929 R2-R5: argument 5930 R15: temporary register for assembler 5931 R16: trampoline register 5932 R28: frame pointer (FP) 5933 R29: global pointer (GP) 5934 R30: link register (LP) 5935 R31: stack pointer (SP) 5936 PC: program counter (PC) 5937 5938 ==> U-Boot will use R10 to hold a pointer to the global data 5939 5940NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5941or current versions of GCC may "optimize" the code too much. 5942 5943Memory Management: 5944------------------ 5945 5946U-Boot runs in system state and uses physical addresses, i.e. the 5947MMU is not used either for address mapping nor for memory protection. 5948 5949The available memory is mapped to fixed addresses using the memory 5950controller. In this process, a contiguous block is formed for each 5951memory type (Flash, SDRAM, SRAM), even when it consists of several 5952physical memory banks. 5953 5954U-Boot is installed in the first 128 kB of the first Flash bank (on 5955TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5956booting and sizing and initializing DRAM, the code relocates itself 5957to the upper end of DRAM. Immediately below the U-Boot code some 5958memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5959configuration setting]. Below that, a structure with global Board 5960Info data is placed, followed by the stack (growing downward). 5961 5962Additionally, some exception handler code is copied to the low 8 kB 5963of DRAM (0x00000000 ... 0x00001FFF). 5964 5965So a typical memory configuration with 16 MB of DRAM could look like 5966this: 5967 5968 0x0000 0000 Exception Vector code 5969 : 5970 0x0000 1FFF 5971 0x0000 2000 Free for Application Use 5972 : 5973 : 5974 5975 : 5976 : 5977 0x00FB FF20 Monitor Stack (Growing downward) 5978 0x00FB FFAC Board Info Data and permanent copy of global data 5979 0x00FC 0000 Malloc Arena 5980 : 5981 0x00FD FFFF 5982 0x00FE 0000 RAM Copy of Monitor Code 5983 ... eventually: LCD or video framebuffer 5984 ... eventually: pRAM (Protected RAM - unchanged by reset) 5985 0x00FF FFFF [End of RAM] 5986 5987 5988System Initialization: 5989---------------------- 5990 5991In the reset configuration, U-Boot starts at the reset entry point 5992(on most PowerPC systems at address 0x00000100). Because of the reset 5993configuration for CS0# this is a mirror of the onboard Flash memory. 5994To be able to re-map memory U-Boot then jumps to its link address. 5995To be able to implement the initialization code in C, a (small!) 5996initial stack is set up in the internal Dual Ported RAM (in case CPUs 5997which provide such a feature like MPC8xx or MPC8260), or in a locked 5998part of the data cache. After that, U-Boot initializes the CPU core, 5999the caches and the SIU. 6000 6001Next, all (potentially) available memory banks are mapped using a 6002preliminary mapping. For example, we put them on 512 MB boundaries 6003(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 6004on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 6005programmed for SDRAM access. Using the temporary configuration, a 6006simple memory test is run that determines the size of the SDRAM 6007banks. 6008 6009When there is more than one SDRAM bank, and the banks are of 6010different size, the largest is mapped first. For equal size, the first 6011bank (CS2#) is mapped first. The first mapping is always for address 60120x00000000, with any additional banks following immediately to create 6013contiguous memory starting from 0. 6014 6015Then, the monitor installs itself at the upper end of the SDRAM area 6016and allocates memory for use by malloc() and for the global Board 6017Info data; also, the exception vector code is copied to the low RAM 6018pages, and the final stack is set up. 6019 6020Only after this relocation will you have a "normal" C environment; 6021until that you are restricted in several ways, mostly because you are 6022running from ROM, and because the code will have to be relocated to a 6023new address in RAM. 6024 6025 6026U-Boot Porting Guide: 6027---------------------- 6028 6029[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6030list, October 2002] 6031 6032 6033int main(int argc, char *argv[]) 6034{ 6035 sighandler_t no_more_time; 6036 6037 signal(SIGALRM, no_more_time); 6038 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6039 6040 if (available_money > available_manpower) { 6041 Pay consultant to port U-Boot; 6042 return 0; 6043 } 6044 6045 Download latest U-Boot source; 6046 6047 Subscribe to u-boot mailing list; 6048 6049 if (clueless) 6050 email("Hi, I am new to U-Boot, how do I get started?"); 6051 6052 while (learning) { 6053 Read the README file in the top level directory; 6054 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6055 Read applicable doc/*.README; 6056 Read the source, Luke; 6057 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6058 } 6059 6060 if (available_money > toLocalCurrency ($2500)) 6061 Buy a BDI3000; 6062 else 6063 Add a lot of aggravation and time; 6064 6065 if (a similar board exists) { /* hopefully... */ 6066 cp -a board/<similar> board/<myboard> 6067 cp include/configs/<similar>.h include/configs/<myboard>.h 6068 } else { 6069 Create your own board support subdirectory; 6070 Create your own board include/configs/<myboard>.h file; 6071 } 6072 Edit new board/<myboard> files 6073 Edit new include/configs/<myboard>.h 6074 6075 while (!accepted) { 6076 while (!running) { 6077 do { 6078 Add / modify source code; 6079 } until (compiles); 6080 Debug; 6081 if (clueless) 6082 email("Hi, I am having problems..."); 6083 } 6084 Send patch file to the U-Boot email list; 6085 if (reasonable critiques) 6086 Incorporate improvements from email list code review; 6087 else 6088 Defend code as written; 6089 } 6090 6091 return 0; 6092} 6093 6094void no_more_time (int sig) 6095{ 6096 hire_a_guru(); 6097} 6098 6099 6100Coding Standards: 6101----------------- 6102 6103All contributions to U-Boot should conform to the Linux kernel 6104coding style; see the file "Documentation/CodingStyle" and the script 6105"scripts/Lindent" in your Linux kernel source directory. 6106 6107Source files originating from a different project (for example the 6108MTD subsystem) are generally exempt from these guidelines and are not 6109reformated to ease subsequent migration to newer versions of those 6110sources. 6111 6112Please note that U-Boot is implemented in C (and to some small parts in 6113Assembler); no C++ is used, so please do not use C++ style comments (//) 6114in your code. 6115 6116Please also stick to the following formatting rules: 6117- remove any trailing white space 6118- use TAB characters for indentation and vertical alignment, not spaces 6119- make sure NOT to use DOS '\r\n' line feeds 6120- do not add more than 2 consecutive empty lines to source files 6121- do not add trailing empty lines to source files 6122 6123Submissions which do not conform to the standards may be returned 6124with a request to reformat the changes. 6125 6126 6127Submitting Patches: 6128------------------- 6129 6130Since the number of patches for U-Boot is growing, we need to 6131establish some rules. Submissions which do not conform to these rules 6132may be rejected, even when they contain important and valuable stuff. 6133 6134Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6135 6136Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6137see http://lists.denx.de/mailman/listinfo/u-boot 6138 6139When you send a patch, please include the following information with 6140it: 6141 6142* For bug fixes: a description of the bug and how your patch fixes 6143 this bug. Please try to include a way of demonstrating that the 6144 patch actually fixes something. 6145 6146* For new features: a description of the feature and your 6147 implementation. 6148 6149* A CHANGELOG entry as plaintext (separate from the patch) 6150 6151* For major contributions, your entry to the CREDITS file 6152 6153* When you add support for a new board, don't forget to add a 6154 maintainer e-mail address to the boards.cfg file, too. 6155 6156* If your patch adds new configuration options, don't forget to 6157 document these in the README file. 6158 6159* The patch itself. If you are using git (which is *strongly* 6160 recommended) you can easily generate the patch using the 6161 "git format-patch". If you then use "git send-email" to send it to 6162 the U-Boot mailing list, you will avoid most of the common problems 6163 with some other mail clients. 6164 6165 If you cannot use git, use "diff -purN OLD NEW". If your version of 6166 diff does not support these options, then get the latest version of 6167 GNU diff. 6168 6169 The current directory when running this command shall be the parent 6170 directory of the U-Boot source tree (i. e. please make sure that 6171 your patch includes sufficient directory information for the 6172 affected files). 6173 6174 We prefer patches as plain text. MIME attachments are discouraged, 6175 and compressed attachments must not be used. 6176 6177* If one logical set of modifications affects or creates several 6178 files, all these changes shall be submitted in a SINGLE patch file. 6179 6180* Changesets that contain different, unrelated modifications shall be 6181 submitted as SEPARATE patches, one patch per changeset. 6182 6183 6184Notes: 6185 6186* Before sending the patch, run the MAKEALL script on your patched 6187 source tree and make sure that no errors or warnings are reported 6188 for any of the boards. 6189 6190* Keep your modifications to the necessary minimum: A patch 6191 containing several unrelated changes or arbitrary reformats will be 6192 returned with a request to re-formatting / split it. 6193 6194* If you modify existing code, make sure that your new code does not 6195 add to the memory footprint of the code ;-) Small is beautiful! 6196 When adding new features, these should compile conditionally only 6197 (using #ifdef), and the resulting code with the new feature 6198 disabled must not need more memory than the old code without your 6199 modification. 6200 6201* Remember that there is a size limit of 100 kB per message on the 6202 u-boot mailing list. Bigger patches will be moderated. If they are 6203 reasonable and not too big, they will be acknowledged. But patches 6204 bigger than the size limit should be avoided. 6205