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 267Configuration Options: 268---------------------- 269 270Configuration depends on the combination of board and CPU type; all 271such information is kept in a configuration file 272"include/configs/<board_name>.h". 273 274Example: For a TQM823L module, all configuration settings are in 275"include/configs/TQM823L.h". 276 277 278Many of the options are named exactly as the corresponding Linux 279kernel configuration options. The intention is to make it easier to 280build a config tool - later. 281 282 283The following options need to be configured: 284 285- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 286 287- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 288 289- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 290 Define exactly one, e.g. CONFIG_ATSTK1002 291 292- CPU Module Type: (if CONFIG_COGENT is defined) 293 Define exactly one of 294 CONFIG_CMA286_60_OLD 295--- FIXME --- not tested yet: 296 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 297 CONFIG_CMA287_23, CONFIG_CMA287_50 298 299- Motherboard Type: (if CONFIG_COGENT is defined) 300 Define exactly one of 301 CONFIG_CMA101, CONFIG_CMA102 302 303- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 304 Define one or more of 305 CONFIG_CMA302 306 307- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 308 Define one or more of 309 CONFIG_LCD_HEARTBEAT - update a character position on 310 the LCD display every second with 311 a "rotator" |\-/|\-/ 312 313- Board flavour: (if CONFIG_MPC8260ADS is defined) 314 CONFIG_ADSTYPE 315 Possible values are: 316 CONFIG_SYS_8260ADS - original MPC8260ADS 317 CONFIG_SYS_8266ADS - MPC8266ADS 318 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 319 CONFIG_SYS_8272ADS - MPC8272ADS 320 321- Marvell Family Member 322 CONFIG_SYS_MVFS - define it if you want to enable 323 multiple fs option at one time 324 for marvell soc family 325 326- MPC824X Family Member (if CONFIG_MPC824X is defined) 327 Define exactly one of 328 CONFIG_MPC8240, CONFIG_MPC8245 329 330- 8xx CPU Options: (if using an MPC8xx CPU) 331 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 332 get_gclk_freq() cannot work 333 e.g. if there is no 32KHz 334 reference PIT/RTC clock 335 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 336 or XTAL/EXTAL) 337 338- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 339 CONFIG_SYS_8xx_CPUCLK_MIN 340 CONFIG_SYS_8xx_CPUCLK_MAX 341 CONFIG_8xx_CPUCLK_DEFAULT 342 See doc/README.MPC866 343 344 CONFIG_SYS_MEASURE_CPUCLK 345 346 Define this to measure the actual CPU clock instead 347 of relying on the correctness of the configured 348 values. Mostly useful for board bringup to make sure 349 the PLL is locked at the intended frequency. Note 350 that this requires a (stable) reference clock (32 kHz 351 RTC clock or CONFIG_SYS_8XX_XIN) 352 353 CONFIG_SYS_DELAYED_ICACHE 354 355 Define this option if you want to enable the 356 ICache only when Code runs from RAM. 357 358- 85xx CPU Options: 359 CONFIG_SYS_PPC64 360 361 Specifies that the core is a 64-bit PowerPC implementation (implements 362 the "64" category of the Power ISA). This is necessary for ePAPR 363 compliance, among other possible reasons. 364 365 CONFIG_SYS_FSL_TBCLK_DIV 366 367 Defines the core time base clock divider ratio compared to the 368 system clock. On most PQ3 devices this is 8, on newer QorIQ 369 devices it can be 16 or 32. The ratio varies from SoC to Soc. 370 371 CONFIG_SYS_FSL_PCIE_COMPAT 372 373 Defines the string to utilize when trying to match PCIe device 374 tree nodes for the given platform. 375 376 CONFIG_SYS_PPC_E500_DEBUG_TLB 377 378 Enables a temporary TLB entry to be used during boot to work 379 around limitations in e500v1 and e500v2 external debugger 380 support. This reduces the portions of the boot code where 381 breakpoints and single stepping do not work. The value of this 382 symbol should be set to the TLB1 entry to be used for this 383 purpose. 384 385 CONFIG_SYS_FSL_ERRATUM_A004510 386 387 Enables a workaround for erratum A004510. If set, 388 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 389 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 390 391 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 392 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 393 394 Defines one or two SoC revisions (low 8 bits of SVR) 395 for which the A004510 workaround should be applied. 396 397 The rest of SVR is either not relevant to the decision 398 of whether the erratum is present (e.g. p2040 versus 399 p2041) or is implied by the build target, which controls 400 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 401 402 See Freescale App Note 4493 for more information about 403 this erratum. 404 405 CONFIG_A003399_NOR_WORKAROUND 406 Enables a workaround for IFC erratum A003399. It is only 407 requred during NOR boot. 408 409 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 410 411 This is the value to write into CCSR offset 0x18600 412 according to the A004510 workaround. 413 414 CONFIG_SYS_FSL_DSP_DDR_ADDR 415 This value denotes start offset of DDR memory which is 416 connected exclusively to the DSP cores. 417 418 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 419 This value denotes start offset of M2 memory 420 which is directly connected to the DSP core. 421 422 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 423 This value denotes start offset of M3 memory which is directly 424 connected to the DSP core. 425 426 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 427 This value denotes start offset of DSP CCSR space. 428 429 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 430 Single Source Clock is clocking mode present in some of FSL SoC's. 431 In this mode, a single differential clock is used to supply 432 clocks to the sysclock, ddrclock and usbclock. 433 434 CONFIG_SYS_CPC_REINIT_F 435 This CONFIG is defined when the CPC is configured as SRAM at the 436 time of U-boot entry and is required to be re-initialized. 437 438 CONFIG_DEEP_SLEEP 439 Inidcates this SoC supports deep sleep feature. If deep sleep is 440 supported, core will start to execute uboot when wakes up. 441 442- Generic CPU options: 443 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 444 445 Defines the endianess of the CPU. Implementation of those 446 values is arch specific. 447 448 CONFIG_SYS_FSL_DDR 449 Freescale DDR driver in use. This type of DDR controller is 450 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 451 SoCs. 452 453 CONFIG_SYS_FSL_DDR_ADDR 454 Freescale DDR memory-mapped register base. 455 456 CONFIG_SYS_FSL_DDR_EMU 457 Specify emulator support for DDR. Some DDR features such as 458 deskew training are not available. 459 460 CONFIG_SYS_FSL_DDRC_GEN1 461 Freescale DDR1 controller. 462 463 CONFIG_SYS_FSL_DDRC_GEN2 464 Freescale DDR2 controller. 465 466 CONFIG_SYS_FSL_DDRC_GEN3 467 Freescale DDR3 controller. 468 469 CONFIG_SYS_FSL_DDRC_GEN4 470 Freescale DDR4 controller. 471 472 CONFIG_SYS_FSL_DDRC_ARM_GEN3 473 Freescale DDR3 controller for ARM-based SoCs. 474 475 CONFIG_SYS_FSL_DDR1 476 Board config to use DDR1. It can be enabled for SoCs with 477 Freescale DDR1 or DDR2 controllers, depending on the board 478 implemetation. 479 480 CONFIG_SYS_FSL_DDR2 481 Board config to use DDR2. It can be eanbeld for SoCs with 482 Freescale DDR2 or DDR3 controllers, depending on the board 483 implementation. 484 485 CONFIG_SYS_FSL_DDR3 486 Board config to use DDR3. It can be enabled for SoCs with 487 Freescale DDR3 or DDR3L controllers. 488 489 CONFIG_SYS_FSL_DDR3L 490 Board config to use DDR3L. It can be enabled for SoCs with 491 DDR3L controllers. 492 493 CONFIG_SYS_FSL_DDR4 494 Board config to use DDR4. It can be enabled for SoCs with 495 DDR4 controllers. 496 497 CONFIG_SYS_FSL_IFC_BE 498 Defines the IFC controller register space as Big Endian 499 500 CONFIG_SYS_FSL_IFC_LE 501 Defines the IFC controller register space as Little Endian 502 503 CONFIG_SYS_FSL_PBL_PBI 504 It enables addition of RCW (Power on reset configuration) in built image. 505 Please refer doc/README.pblimage for more details 506 507 CONFIG_SYS_FSL_PBL_RCW 508 It adds PBI(pre-boot instructions) commands in u-boot build image. 509 PBI commands can be used to configure SoC before it starts the execution. 510 Please refer doc/README.pblimage for more details 511 512 CONFIG_SPL_FSL_PBL 513 It adds a target to create boot binary having SPL binary in PBI format 514 concatenated with u-boot binary. 515 516 CONFIG_SYS_FSL_DDR_BE 517 Defines the DDR controller register space as Big Endian 518 519 CONFIG_SYS_FSL_DDR_LE 520 Defines the DDR controller register space as Little Endian 521 522 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 523 Physical address from the view of DDR controllers. It is the 524 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 525 it could be different for ARM SoCs. 526 527 CONFIG_SYS_FSL_DDR_INTLV_256B 528 DDR controller interleaving on 256-byte. This is a special 529 interleaving mode, handled by Dickens for Freescale layerscape 530 SoCs with ARM core. 531 532- Intel Monahans options: 533 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 534 535 Defines the Monahans run mode to oscillator 536 ratio. Valid values are 8, 16, 24, 31. The core 537 frequency is this value multiplied by 13 MHz. 538 539 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 540 541 Defines the Monahans turbo mode to oscillator 542 ratio. Valid values are 1 (default if undefined) and 543 2. The core frequency as calculated above is multiplied 544 by this value. 545 546- MIPS CPU options: 547 CONFIG_SYS_INIT_SP_OFFSET 548 549 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 550 pointer. This is needed for the temporary stack before 551 relocation. 552 553 CONFIG_SYS_MIPS_CACHE_MODE 554 555 Cache operation mode for the MIPS CPU. 556 See also arch/mips/include/asm/mipsregs.h. 557 Possible values are: 558 CONF_CM_CACHABLE_NO_WA 559 CONF_CM_CACHABLE_WA 560 CONF_CM_UNCACHED 561 CONF_CM_CACHABLE_NONCOHERENT 562 CONF_CM_CACHABLE_CE 563 CONF_CM_CACHABLE_COW 564 CONF_CM_CACHABLE_CUW 565 CONF_CM_CACHABLE_ACCELERATED 566 567 CONFIG_SYS_XWAY_EBU_BOOTCFG 568 569 Special option for Lantiq XWAY SoCs for booting from NOR flash. 570 See also arch/mips/cpu/mips32/start.S. 571 572 CONFIG_XWAY_SWAP_BYTES 573 574 Enable compilation of tools/xway-swap-bytes needed for Lantiq 575 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 576 be swapped if a flash programmer is used. 577 578- ARM options: 579 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 580 581 Select high exception vectors of the ARM core, e.g., do not 582 clear the V bit of the c1 register of CP15. 583 584 CONFIG_SYS_THUMB_BUILD 585 586 Use this flag to build U-Boot using the Thumb instruction 587 set for ARM architectures. Thumb instruction set provides 588 better code density. For ARM architectures that support 589 Thumb2 this flag will result in Thumb2 code generated by 590 GCC. 591 592 CONFIG_ARM_ERRATA_716044 593 CONFIG_ARM_ERRATA_742230 594 CONFIG_ARM_ERRATA_743622 595 CONFIG_ARM_ERRATA_751472 596 CONFIG_ARM_ERRATA_794072 597 CONFIG_ARM_ERRATA_761320 598 599 If set, the workarounds for these ARM errata are applied early 600 during U-Boot startup. Note that these options force the 601 workarounds to be applied; no CPU-type/version detection 602 exists, unlike the similar options in the Linux kernel. Do not 603 set these options unless they apply! 604 605- CPU timer options: 606 CONFIG_SYS_HZ 607 608 The frequency of the timer returned by get_timer(). 609 get_timer() must operate in milliseconds and this CONFIG 610 option must be set to 1000. 611 612- Linux Kernel Interface: 613 CONFIG_CLOCKS_IN_MHZ 614 615 U-Boot stores all clock information in Hz 616 internally. For binary compatibility with older Linux 617 kernels (which expect the clocks passed in the 618 bd_info data to be in MHz) the environment variable 619 "clocks_in_mhz" can be defined so that U-Boot 620 converts clock data to MHZ before passing it to the 621 Linux kernel. 622 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 623 "clocks_in_mhz=1" is automatically included in the 624 default environment. 625 626 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 627 628 When transferring memsize parameter to linux, some versions 629 expect it to be in bytes, others in MB. 630 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 631 632 CONFIG_OF_LIBFDT 633 634 New kernel versions are expecting firmware settings to be 635 passed using flattened device trees (based on open firmware 636 concepts). 637 638 CONFIG_OF_LIBFDT 639 * New libfdt-based support 640 * Adds the "fdt" command 641 * The bootm command automatically updates the fdt 642 643 OF_CPU - The proper name of the cpus node (only required for 644 MPC512X and MPC5xxx based boards). 645 OF_SOC - The proper name of the soc node (only required for 646 MPC512X and MPC5xxx based boards). 647 OF_TBCLK - The timebase frequency. 648 OF_STDOUT_PATH - The path to the console device 649 650 boards with QUICC Engines require OF_QE to set UCC MAC 651 addresses 652 653 CONFIG_OF_BOARD_SETUP 654 655 Board code has addition modification that it wants to make 656 to the flat device tree before handing it off to the kernel 657 658 CONFIG_OF_BOOT_CPU 659 660 This define fills in the correct boot CPU in the boot 661 param header, the default value is zero if undefined. 662 663 CONFIG_OF_IDE_FIXUP 664 665 U-Boot can detect if an IDE device is present or not. 666 If not, and this new config option is activated, U-Boot 667 removes the ATA node from the DTS before booting Linux, 668 so the Linux IDE driver does not probe the device and 669 crash. This is needed for buggy hardware (uc101) where 670 no pull down resistor is connected to the signal IDE5V_DD7. 671 672 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 673 674 This setting is mandatory for all boards that have only one 675 machine type and must be used to specify the machine type 676 number as it appears in the ARM machine registry 677 (see http://www.arm.linux.org.uk/developer/machines/). 678 Only boards that have multiple machine types supported 679 in a single configuration file and the machine type is 680 runtime discoverable, do not have to use this setting. 681 682- vxWorks boot parameters: 683 684 bootvx constructs a valid bootline using the following 685 environments variables: bootfile, ipaddr, serverip, hostname. 686 It loads the vxWorks image pointed bootfile. 687 688 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 689 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 690 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 691 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 692 693 CONFIG_SYS_VXWORKS_ADD_PARAMS 694 695 Add it at the end of the bootline. E.g "u=username pw=secret" 696 697 Note: If a "bootargs" environment is defined, it will overwride 698 the defaults discussed just above. 699 700- Cache Configuration: 701 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 702 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 703 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 704 705- Cache Configuration for ARM: 706 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 707 controller 708 CONFIG_SYS_PL310_BASE - Physical base address of PL310 709 controller register space 710 711- Serial Ports: 712 CONFIG_PL010_SERIAL 713 714 Define this if you want support for Amba PrimeCell PL010 UARTs. 715 716 CONFIG_PL011_SERIAL 717 718 Define this if you want support for Amba PrimeCell PL011 UARTs. 719 720 CONFIG_PL011_CLOCK 721 722 If you have Amba PrimeCell PL011 UARTs, set this variable to 723 the clock speed of the UARTs. 724 725 CONFIG_PL01x_PORTS 726 727 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 728 define this to a list of base addresses for each (supported) 729 port. See e.g. include/configs/versatile.h 730 731 CONFIG_PL011_SERIAL_RLCR 732 733 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 734 have separate receive and transmit line control registers. Set 735 this variable to initialize the extra register. 736 737 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 738 739 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 740 boot loader that has already initialized the UART. Define this 741 variable to flush the UART at init time. 742 743 744- Console Interface: 745 Depending on board, define exactly one serial port 746 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 747 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 748 console by defining CONFIG_8xx_CONS_NONE 749 750 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 751 port routines must be defined elsewhere 752 (i.e. serial_init(), serial_getc(), ...) 753 754 CONFIG_CFB_CONSOLE 755 Enables console device for a color framebuffer. Needs following 756 defines (cf. smiLynxEM, i8042) 757 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 758 (default big endian) 759 VIDEO_HW_RECTFILL graphic chip supports 760 rectangle fill 761 (cf. smiLynxEM) 762 VIDEO_HW_BITBLT graphic chip supports 763 bit-blit (cf. smiLynxEM) 764 VIDEO_VISIBLE_COLS visible pixel columns 765 (cols=pitch) 766 VIDEO_VISIBLE_ROWS visible pixel rows 767 VIDEO_PIXEL_SIZE bytes per pixel 768 VIDEO_DATA_FORMAT graphic data format 769 (0-5, cf. cfb_console.c) 770 VIDEO_FB_ADRS framebuffer address 771 VIDEO_KBD_INIT_FCT keyboard int fct 772 (i.e. i8042_kbd_init()) 773 VIDEO_TSTC_FCT test char fct 774 (i.e. i8042_tstc) 775 VIDEO_GETC_FCT get char fct 776 (i.e. i8042_getc) 777 CONFIG_CONSOLE_CURSOR cursor drawing on/off 778 (requires blink timer 779 cf. i8042.c) 780 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 781 CONFIG_CONSOLE_TIME display time/date info in 782 upper right corner 783 (requires CONFIG_CMD_DATE) 784 CONFIG_VIDEO_LOGO display Linux logo in 785 upper left corner 786 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 787 linux_logo.h for logo. 788 Requires CONFIG_VIDEO_LOGO 789 CONFIG_CONSOLE_EXTRA_INFO 790 additional board info beside 791 the logo 792 793 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 794 a limited number of ANSI escape sequences (cursor control, 795 erase functions and limited graphics rendition control). 796 797 When CONFIG_CFB_CONSOLE is defined, video console is 798 default i/o. Serial console can be forced with 799 environment 'console=serial'. 800 801 When CONFIG_SILENT_CONSOLE is defined, all console 802 messages (by U-Boot and Linux!) can be silenced with 803 the "silent" environment variable. See 804 doc/README.silent for more information. 805 806 CONFIG_SYS_CONSOLE_BG_COL: define the backgroundcolor, default 807 is 0x00. 808 CONFIG_SYS_CONSOLE_FG_COL: define the foregroundcolor, default 809 is 0xa0. 810 811- Console Baudrate: 812 CONFIG_BAUDRATE - in bps 813 Select one of the baudrates listed in 814 CONFIG_SYS_BAUDRATE_TABLE, see below. 815 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 816 817- Console Rx buffer length 818 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 819 the maximum receive buffer length for the SMC. 820 This option is actual only for 82xx and 8xx possible. 821 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 822 must be defined, to setup the maximum idle timeout for 823 the SMC. 824 825- Pre-Console Buffer: 826 Prior to the console being initialised (i.e. serial UART 827 initialised etc) all console output is silently discarded. 828 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 829 buffer any console messages prior to the console being 830 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 831 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 832 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 833 bytes are output before the console is initialised, the 834 earlier bytes are discarded. 835 836 'Sane' compilers will generate smaller code if 837 CONFIG_PRE_CON_BUF_SZ is a power of 2 838 839- Safe printf() functions 840 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 841 the printf() functions. These are defined in 842 include/vsprintf.h and include snprintf(), vsnprintf() and 843 so on. Code size increase is approximately 300-500 bytes. 844 If this option is not given then these functions will 845 silently discard their buffer size argument - this means 846 you are not getting any overflow checking in this case. 847 848- Boot Delay: CONFIG_BOOTDELAY - in seconds 849 Delay before automatically booting the default image; 850 set to -1 to disable autoboot. 851 set to -2 to autoboot with no delay and not check for abort 852 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 853 854 See doc/README.autoboot for these options that 855 work with CONFIG_BOOTDELAY. None are required. 856 CONFIG_BOOT_RETRY_TIME 857 CONFIG_BOOT_RETRY_MIN 858 CONFIG_AUTOBOOT_KEYED 859 CONFIG_AUTOBOOT_PROMPT 860 CONFIG_AUTOBOOT_DELAY_STR 861 CONFIG_AUTOBOOT_STOP_STR 862 CONFIG_AUTOBOOT_DELAY_STR2 863 CONFIG_AUTOBOOT_STOP_STR2 864 CONFIG_ZERO_BOOTDELAY_CHECK 865 CONFIG_RESET_TO_RETRY 866 867- Autoboot Command: 868 CONFIG_BOOTCOMMAND 869 Only needed when CONFIG_BOOTDELAY is enabled; 870 define a command string that is automatically executed 871 when no character is read on the console interface 872 within "Boot Delay" after reset. 873 874 CONFIG_BOOTARGS 875 This can be used to pass arguments to the bootm 876 command. The value of CONFIG_BOOTARGS goes into the 877 environment value "bootargs". 878 879 CONFIG_RAMBOOT and CONFIG_NFSBOOT 880 The value of these goes into the environment as 881 "ramboot" and "nfsboot" respectively, and can be used 882 as a convenience, when switching between booting from 883 RAM and NFS. 884 885- Bootcount: 886 CONFIG_BOOTCOUNT_LIMIT 887 Implements a mechanism for detecting a repeating reboot 888 cycle, see: 889 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 890 891 CONFIG_BOOTCOUNT_ENV 892 If no softreset save registers are found on the hardware 893 "bootcount" is stored in the environment. To prevent a 894 saveenv on all reboots, the environment variable 895 "upgrade_available" is used. If "upgrade_available" is 896 0, "bootcount" is always 0, if "upgrade_available" is 897 1 "bootcount" is incremented in the environment. 898 So the Userspace Applikation must set the "upgrade_available" 899 and "bootcount" variable to 0, if a boot was successfully. 900 901- Pre-Boot Commands: 902 CONFIG_PREBOOT 903 904 When this option is #defined, the existence of the 905 environment variable "preboot" will be checked 906 immediately before starting the CONFIG_BOOTDELAY 907 countdown and/or running the auto-boot command resp. 908 entering interactive mode. 909 910 This feature is especially useful when "preboot" is 911 automatically generated or modified. For an example 912 see the LWMON board specific code: here "preboot" is 913 modified when the user holds down a certain 914 combination of keys on the (special) keyboard when 915 booting the systems 916 917- Serial Download Echo Mode: 918 CONFIG_LOADS_ECHO 919 If defined to 1, all characters received during a 920 serial download (using the "loads" command) are 921 echoed back. This might be needed by some terminal 922 emulations (like "cu"), but may as well just take 923 time on others. This setting #define's the initial 924 value of the "loads_echo" environment variable. 925 926- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 927 CONFIG_KGDB_BAUDRATE 928 Select one of the baudrates listed in 929 CONFIG_SYS_BAUDRATE_TABLE, see below. 930 931- Monitor Functions: 932 Monitor commands can be included or excluded 933 from the build by using the #include files 934 <config_cmd_all.h> and #undef'ing unwanted 935 commands, or using <config_cmd_default.h> 936 and augmenting with additional #define's 937 for wanted commands. 938 939 The default command configuration includes all commands 940 except those marked below with a "*". 941 942 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 943 CONFIG_CMD_ASKENV * ask for env variable 944 CONFIG_CMD_BDI bdinfo 945 CONFIG_CMD_BEDBUG * Include BedBug Debugger 946 CONFIG_CMD_BMP * BMP support 947 CONFIG_CMD_BSP * Board specific commands 948 CONFIG_CMD_BOOTD bootd 949 CONFIG_CMD_CACHE * icache, dcache 950 CONFIG_CMD_CLK * clock command support 951 CONFIG_CMD_CONSOLE coninfo 952 CONFIG_CMD_CRC32 * crc32 953 CONFIG_CMD_DATE * support for RTC, date/time... 954 CONFIG_CMD_DHCP * DHCP support 955 CONFIG_CMD_DIAG * Diagnostics 956 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 957 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 958 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 959 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 960 CONFIG_CMD_DTT * Digital Therm and Thermostat 961 CONFIG_CMD_ECHO echo arguments 962 CONFIG_CMD_EDITENV edit env variable 963 CONFIG_CMD_EEPROM * EEPROM read/write support 964 CONFIG_CMD_ELF * bootelf, bootvx 965 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 966 CONFIG_CMD_ENV_FLAGS * display details about env flags 967 CONFIG_CMD_ENV_EXISTS * check existence of env variable 968 CONFIG_CMD_EXPORTENV * export the environment 969 CONFIG_CMD_EXT2 * ext2 command support 970 CONFIG_CMD_EXT4 * ext4 command support 971 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 972 that work for multiple fs types 973 CONFIG_CMD_SAVEENV saveenv 974 CONFIG_CMD_FDC * Floppy Disk Support 975 CONFIG_CMD_FAT * FAT command support 976 CONFIG_CMD_FLASH flinfo, erase, protect 977 CONFIG_CMD_FPGA FPGA device initialization support 978 CONFIG_CMD_FUSE * Device fuse support 979 CONFIG_CMD_GETTIME * Get time since boot 980 CONFIG_CMD_GO * the 'go' command (exec code) 981 CONFIG_CMD_GREPENV * search environment 982 CONFIG_CMD_HASH * calculate hash / digest 983 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 984 CONFIG_CMD_I2C * I2C serial bus support 985 CONFIG_CMD_IDE * IDE harddisk support 986 CONFIG_CMD_IMI iminfo 987 CONFIG_CMD_IMLS List all images found in NOR flash 988 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 989 CONFIG_CMD_IMMAP * IMMR dump support 990 CONFIG_CMD_IMPORTENV * import an environment 991 CONFIG_CMD_INI * import data from an ini file into the env 992 CONFIG_CMD_IRQ * irqinfo 993 CONFIG_CMD_ITEST Integer/string test of 2 values 994 CONFIG_CMD_JFFS2 * JFFS2 Support 995 CONFIG_CMD_KGDB * kgdb 996 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 997 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 998 (169.254.*.*) 999 CONFIG_CMD_LOADB loadb 1000 CONFIG_CMD_LOADS loads 1001 CONFIG_CMD_MD5SUM * print md5 message digest 1002 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 1003 CONFIG_CMD_MEMINFO * Display detailed memory information 1004 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 1005 loop, loopw 1006 CONFIG_CMD_MEMTEST * mtest 1007 CONFIG_CMD_MISC Misc functions like sleep etc 1008 CONFIG_CMD_MMC * MMC memory mapped support 1009 CONFIG_CMD_MII * MII utility commands 1010 CONFIG_CMD_MTDPARTS * MTD partition support 1011 CONFIG_CMD_NAND * NAND support 1012 CONFIG_CMD_NET bootp, tftpboot, rarpboot 1013 CONFIG_CMD_NFS NFS support 1014 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 1015 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 1016 CONFIG_CMD_PCI * pciinfo 1017 CONFIG_CMD_PCMCIA * PCMCIA support 1018 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 1019 host 1020 CONFIG_CMD_PORTIO * Port I/O 1021 CONFIG_CMD_READ * Read raw data from partition 1022 CONFIG_CMD_REGINFO * Register dump 1023 CONFIG_CMD_RUN run command in env variable 1024 CONFIG_CMD_SANDBOX * sb command to access sandbox features 1025 CONFIG_CMD_SAVES * save S record dump 1026 CONFIG_CMD_SCSI * SCSI Support 1027 CONFIG_CMD_SDRAM * print SDRAM configuration information 1028 (requires CONFIG_CMD_I2C) 1029 CONFIG_CMD_SETGETDCR Support for DCR Register access 1030 (4xx only) 1031 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 1032 CONFIG_CMD_SHA1SUM * print sha1 memory digest 1033 (requires CONFIG_CMD_MEMORY) 1034 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 1035 CONFIG_CMD_SOURCE "source" command Support 1036 CONFIG_CMD_SPI * SPI serial bus support 1037 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 1038 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 1039 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 1040 CONFIG_CMD_TIMER * access to the system tick timer 1041 CONFIG_CMD_USB * USB support 1042 CONFIG_CMD_CDP * Cisco Discover Protocol support 1043 CONFIG_CMD_MFSL * Microblaze FSL support 1044 CONFIG_CMD_XIMG Load part of Multi Image 1045 CONFIG_CMD_UUID * Generate random UUID or GUID string 1046 1047 EXAMPLE: If you want all functions except of network 1048 support you can write: 1049 1050 #include "config_cmd_all.h" 1051 #undef CONFIG_CMD_NET 1052 1053 Other Commands: 1054 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 1055 1056 Note: Don't enable the "icache" and "dcache" commands 1057 (configuration option CONFIG_CMD_CACHE) unless you know 1058 what you (and your U-Boot users) are doing. Data 1059 cache cannot be enabled on systems like the 8xx or 1060 8260 (where accesses to the IMMR region must be 1061 uncached), and it cannot be disabled on all other 1062 systems where we (mis-) use the data cache to hold an 1063 initial stack and some data. 1064 1065 1066 XXX - this list needs to get updated! 1067 1068- Regular expression support: 1069 CONFIG_REGEX 1070 If this variable is defined, U-Boot is linked against 1071 the SLRE (Super Light Regular Expression) library, 1072 which adds regex support to some commands, as for 1073 example "env grep" and "setexpr". 1074 1075- Device tree: 1076 CONFIG_OF_CONTROL 1077 If this variable is defined, U-Boot will use a device tree 1078 to configure its devices, instead of relying on statically 1079 compiled #defines in the board file. This option is 1080 experimental and only available on a few boards. The device 1081 tree is available in the global data as gd->fdt_blob. 1082 1083 U-Boot needs to get its device tree from somewhere. This can 1084 be done using one of the two options below: 1085 1086 CONFIG_OF_EMBED 1087 If this variable is defined, U-Boot will embed a device tree 1088 binary in its image. This device tree file should be in the 1089 board directory and called <soc>-<board>.dts. The binary file 1090 is then picked up in board_init_f() and made available through 1091 the global data structure as gd->blob. 1092 1093 CONFIG_OF_SEPARATE 1094 If this variable is defined, U-Boot will build a device tree 1095 binary. It will be called u-boot.dtb. Architecture-specific 1096 code will locate it at run-time. Generally this works by: 1097 1098 cat u-boot.bin u-boot.dtb >image.bin 1099 1100 and in fact, U-Boot does this for you, creating a file called 1101 u-boot-dtb.bin which is useful in the common case. You can 1102 still use the individual files if you need something more 1103 exotic. 1104 1105- Watchdog: 1106 CONFIG_WATCHDOG 1107 If this variable is defined, it enables watchdog 1108 support for the SoC. There must be support in the SoC 1109 specific code for a watchdog. For the 8xx and 8260 1110 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1111 register. When supported for a specific SoC is 1112 available, then no further board specific code should 1113 be needed to use it. 1114 1115 CONFIG_HW_WATCHDOG 1116 When using a watchdog circuitry external to the used 1117 SoC, then define this variable and provide board 1118 specific code for the "hw_watchdog_reset" function. 1119 1120- U-Boot Version: 1121 CONFIG_VERSION_VARIABLE 1122 If this variable is defined, an environment variable 1123 named "ver" is created by U-Boot showing the U-Boot 1124 version as printed by the "version" command. 1125 Any change to this variable will be reverted at the 1126 next reset. 1127 1128- Real-Time Clock: 1129 1130 When CONFIG_CMD_DATE is selected, the type of the RTC 1131 has to be selected, too. Define exactly one of the 1132 following options: 1133 1134 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1135 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1136 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1137 CONFIG_RTC_MC146818 - use MC146818 RTC 1138 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1139 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1140 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1141 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1142 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1143 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1144 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1145 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1146 RV3029 RTC. 1147 1148 Note that if the RTC uses I2C, then the I2C interface 1149 must also be configured. See I2C Support, below. 1150 1151- GPIO Support: 1152 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1153 1154 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1155 chip-ngpio pairs that tell the PCA953X driver the number of 1156 pins supported by a particular chip. 1157 1158 Note that if the GPIO device uses I2C, then the I2C interface 1159 must also be configured. See I2C Support, below. 1160 1161- Timestamp Support: 1162 1163 When CONFIG_TIMESTAMP is selected, the timestamp 1164 (date and time) of an image is printed by image 1165 commands like bootm or iminfo. This option is 1166 automatically enabled when you select CONFIG_CMD_DATE . 1167 1168- Partition Labels (disklabels) Supported: 1169 Zero or more of the following: 1170 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1171 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1172 Intel architecture, USB sticks, etc. 1173 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1174 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1175 bootloader. Note 2TB partition limit; see 1176 disk/part_efi.c 1177 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1178 1179 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1180 CONFIG_CMD_SCSI) you must configure support for at 1181 least one non-MTD partition type as well. 1182 1183- IDE Reset method: 1184 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1185 board configurations files but used nowhere! 1186 1187 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1188 be performed by calling the function 1189 ide_set_reset(int reset) 1190 which has to be defined in a board specific file 1191 1192- ATAPI Support: 1193 CONFIG_ATAPI 1194 1195 Set this to enable ATAPI support. 1196 1197- LBA48 Support 1198 CONFIG_LBA48 1199 1200 Set this to enable support for disks larger than 137GB 1201 Also look at CONFIG_SYS_64BIT_LBA. 1202 Whithout these , LBA48 support uses 32bit variables and will 'only' 1203 support disks up to 2.1TB. 1204 1205 CONFIG_SYS_64BIT_LBA: 1206 When enabled, makes the IDE subsystem use 64bit sector addresses. 1207 Default is 32bit. 1208 1209- SCSI Support: 1210 At the moment only there is only support for the 1211 SYM53C8XX SCSI controller; define 1212 CONFIG_SCSI_SYM53C8XX to enable it. 1213 1214 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1215 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1216 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1217 maximum numbers of LUNs, SCSI ID's and target 1218 devices. 1219 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1220 1221 The environment variable 'scsidevs' is set to the number of 1222 SCSI devices found during the last scan. 1223 1224- NETWORK Support (PCI): 1225 CONFIG_E1000 1226 Support for Intel 8254x/8257x gigabit chips. 1227 1228 CONFIG_E1000_SPI 1229 Utility code for direct access to the SPI bus on Intel 8257x. 1230 This does not do anything useful unless you set at least one 1231 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1232 1233 CONFIG_E1000_SPI_GENERIC 1234 Allow generic access to the SPI bus on the Intel 8257x, for 1235 example with the "sspi" command. 1236 1237 CONFIG_CMD_E1000 1238 Management command for E1000 devices. When used on devices 1239 with SPI support you can reprogram the EEPROM from U-Boot. 1240 1241 CONFIG_E1000_FALLBACK_MAC 1242 default MAC for empty EEPROM after production. 1243 1244 CONFIG_EEPRO100 1245 Support for Intel 82557/82559/82559ER chips. 1246 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1247 write routine for first time initialisation. 1248 1249 CONFIG_TULIP 1250 Support for Digital 2114x chips. 1251 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1252 modem chip initialisation (KS8761/QS6611). 1253 1254 CONFIG_NATSEMI 1255 Support for National dp83815 chips. 1256 1257 CONFIG_NS8382X 1258 Support for National dp8382[01] gigabit chips. 1259 1260- NETWORK Support (other): 1261 1262 CONFIG_DRIVER_AT91EMAC 1263 Support for AT91RM9200 EMAC. 1264 1265 CONFIG_RMII 1266 Define this to use reduced MII inteface 1267 1268 CONFIG_DRIVER_AT91EMAC_QUIET 1269 If this defined, the driver is quiet. 1270 The driver doen't show link status messages. 1271 1272 CONFIG_CALXEDA_XGMAC 1273 Support for the Calxeda XGMAC device 1274 1275 CONFIG_LAN91C96 1276 Support for SMSC's LAN91C96 chips. 1277 1278 CONFIG_LAN91C96_BASE 1279 Define this to hold the physical address 1280 of the LAN91C96's I/O space 1281 1282 CONFIG_LAN91C96_USE_32_BIT 1283 Define this to enable 32 bit addressing 1284 1285 CONFIG_SMC91111 1286 Support for SMSC's LAN91C111 chip 1287 1288 CONFIG_SMC91111_BASE 1289 Define this to hold the physical address 1290 of the device (I/O space) 1291 1292 CONFIG_SMC_USE_32_BIT 1293 Define this if data bus is 32 bits 1294 1295 CONFIG_SMC_USE_IOFUNCS 1296 Define this to use i/o functions instead of macros 1297 (some hardware wont work with macros) 1298 1299 CONFIG_DRIVER_TI_EMAC 1300 Support for davinci emac 1301 1302 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1303 Define this if you have more then 3 PHYs. 1304 1305 CONFIG_FTGMAC100 1306 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1307 1308 CONFIG_FTGMAC100_EGIGA 1309 Define this to use GE link update with gigabit PHY. 1310 Define this if FTGMAC100 is connected to gigabit PHY. 1311 If your system has 10/100 PHY only, it might not occur 1312 wrong behavior. Because PHY usually return timeout or 1313 useless data when polling gigabit status and gigabit 1314 control registers. This behavior won't affect the 1315 correctnessof 10/100 link speed update. 1316 1317 CONFIG_SMC911X 1318 Support for SMSC's LAN911x and LAN921x chips 1319 1320 CONFIG_SMC911X_BASE 1321 Define this to hold the physical address 1322 of the device (I/O space) 1323 1324 CONFIG_SMC911X_32_BIT 1325 Define this if data bus is 32 bits 1326 1327 CONFIG_SMC911X_16_BIT 1328 Define this if data bus is 16 bits. If your processor 1329 automatically converts one 32 bit word to two 16 bit 1330 words you may also try CONFIG_SMC911X_32_BIT. 1331 1332 CONFIG_SH_ETHER 1333 Support for Renesas on-chip Ethernet controller 1334 1335 CONFIG_SH_ETHER_USE_PORT 1336 Define the number of ports to be used 1337 1338 CONFIG_SH_ETHER_PHY_ADDR 1339 Define the ETH PHY's address 1340 1341 CONFIG_SH_ETHER_CACHE_WRITEBACK 1342 If this option is set, the driver enables cache flush. 1343 1344- TPM Support: 1345 CONFIG_TPM 1346 Support TPM devices. 1347 1348 CONFIG_TPM_TIS_I2C 1349 Support for i2c bus TPM devices. Only one device 1350 per system is supported at this time. 1351 1352 CONFIG_TPM_TIS_I2C_BUS_NUMBER 1353 Define the the i2c bus number for the TPM device 1354 1355 CONFIG_TPM_TIS_I2C_SLAVE_ADDRESS 1356 Define the TPM's address on the i2c bus 1357 1358 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1359 Define the burst count bytes upper limit 1360 1361 CONFIG_TPM_ATMEL_TWI 1362 Support for Atmel TWI TPM device. Requires I2C support. 1363 1364 CONFIG_TPM_TIS_LPC 1365 Support for generic parallel port TPM devices. Only one device 1366 per system is supported at this time. 1367 1368 CONFIG_TPM_TIS_BASE_ADDRESS 1369 Base address where the generic TPM device is mapped 1370 to. Contemporary x86 systems usually map it at 1371 0xfed40000. 1372 1373 CONFIG_CMD_TPM 1374 Add tpm monitor functions. 1375 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1376 provides monitor access to authorized functions. 1377 1378 CONFIG_TPM 1379 Define this to enable the TPM support library which provides 1380 functional interfaces to some TPM commands. 1381 Requires support for a TPM device. 1382 1383 CONFIG_TPM_AUTH_SESSIONS 1384 Define this to enable authorized functions in the TPM library. 1385 Requires CONFIG_TPM and CONFIG_SHA1. 1386 1387- USB Support: 1388 At the moment only the UHCI host controller is 1389 supported (PIP405, MIP405, MPC5200); define 1390 CONFIG_USB_UHCI to enable it. 1391 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1392 and define CONFIG_USB_STORAGE to enable the USB 1393 storage devices. 1394 Note: 1395 Supported are USB Keyboards and USB Floppy drives 1396 (TEAC FD-05PUB). 1397 MPC5200 USB requires additional defines: 1398 CONFIG_USB_CLOCK 1399 for 528 MHz Clock: 0x0001bbbb 1400 CONFIG_PSC3_USB 1401 for USB on PSC3 1402 CONFIG_USB_CONFIG 1403 for differential drivers: 0x00001000 1404 for single ended drivers: 0x00005000 1405 for differential drivers on PSC3: 0x00000100 1406 for single ended drivers on PSC3: 0x00004100 1407 CONFIG_SYS_USB_EVENT_POLL 1408 May be defined to allow interrupt polling 1409 instead of using asynchronous interrupts 1410 1411 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1412 txfilltuning field in the EHCI controller on reset. 1413 1414 CONFIG_USB_HUB_MIN_POWER_ON_DELAY defines the minimum 1415 interval for usb hub power-on delay.(minimum 100msec) 1416 1417- USB Device: 1418 Define the below if you wish to use the USB console. 1419 Once firmware is rebuilt from a serial console issue the 1420 command "setenv stdin usbtty; setenv stdout usbtty" and 1421 attach your USB cable. The Unix command "dmesg" should print 1422 it has found a new device. The environment variable usbtty 1423 can be set to gserial or cdc_acm to enable your device to 1424 appear to a USB host as a Linux gserial device or a 1425 Common Device Class Abstract Control Model serial device. 1426 If you select usbtty = gserial you should be able to enumerate 1427 a Linux host by 1428 # modprobe usbserial vendor=0xVendorID product=0xProductID 1429 else if using cdc_acm, simply setting the environment 1430 variable usbtty to be cdc_acm should suffice. The following 1431 might be defined in YourBoardName.h 1432 1433 CONFIG_USB_DEVICE 1434 Define this to build a UDC device 1435 1436 CONFIG_USB_TTY 1437 Define this to have a tty type of device available to 1438 talk to the UDC device 1439 1440 CONFIG_USBD_HS 1441 Define this to enable the high speed support for usb 1442 device and usbtty. If this feature is enabled, a routine 1443 int is_usbd_high_speed(void) 1444 also needs to be defined by the driver to dynamically poll 1445 whether the enumeration has succeded at high speed or full 1446 speed. 1447 1448 CONFIG_SYS_CONSOLE_IS_IN_ENV 1449 Define this if you want stdin, stdout &/or stderr to 1450 be set to usbtty. 1451 1452 mpc8xx: 1453 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1454 Derive USB clock from external clock "blah" 1455 - CONFIG_SYS_USB_EXTC_CLK 0x02 1456 1457 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1458 Derive USB clock from brgclk 1459 - CONFIG_SYS_USB_BRG_CLK 0x04 1460 1461 If you have a USB-IF assigned VendorID then you may wish to 1462 define your own vendor specific values either in BoardName.h 1463 or directly in usbd_vendor_info.h. If you don't define 1464 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1465 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1466 should pretend to be a Linux device to it's target host. 1467 1468 CONFIG_USBD_MANUFACTURER 1469 Define this string as the name of your company for 1470 - CONFIG_USBD_MANUFACTURER "my company" 1471 1472 CONFIG_USBD_PRODUCT_NAME 1473 Define this string as the name of your product 1474 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1475 1476 CONFIG_USBD_VENDORID 1477 Define this as your assigned Vendor ID from the USB 1478 Implementors Forum. This *must* be a genuine Vendor ID 1479 to avoid polluting the USB namespace. 1480 - CONFIG_USBD_VENDORID 0xFFFF 1481 1482 CONFIG_USBD_PRODUCTID 1483 Define this as the unique Product ID 1484 for your device 1485 - CONFIG_USBD_PRODUCTID 0xFFFF 1486 1487- ULPI Layer Support: 1488 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1489 the generic ULPI layer. The generic layer accesses the ULPI PHY 1490 via the platform viewport, so you need both the genric layer and 1491 the viewport enabled. Currently only Chipidea/ARC based 1492 viewport is supported. 1493 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1494 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1495 If your ULPI phy needs a different reference clock than the 1496 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1497 the appropriate value in Hz. 1498 1499- MMC Support: 1500 The MMC controller on the Intel PXA is supported. To 1501 enable this define CONFIG_MMC. The MMC can be 1502 accessed from the boot prompt by mapping the device 1503 to physical memory similar to flash. Command line is 1504 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1505 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1506 1507 CONFIG_SH_MMCIF 1508 Support for Renesas on-chip MMCIF controller 1509 1510 CONFIG_SH_MMCIF_ADDR 1511 Define the base address of MMCIF registers 1512 1513 CONFIG_SH_MMCIF_CLK 1514 Define the clock frequency for MMCIF 1515 1516- USB Device Firmware Update (DFU) class support: 1517 CONFIG_DFU_FUNCTION 1518 This enables the USB portion of the DFU USB class 1519 1520 CONFIG_CMD_DFU 1521 This enables the command "dfu" which is used to have 1522 U-Boot create a DFU class device via USB. This command 1523 requires that the "dfu_alt_info" environment variable be 1524 set and define the alt settings to expose to the host. 1525 1526 CONFIG_DFU_MMC 1527 This enables support for exposing (e)MMC devices via DFU. 1528 1529 CONFIG_DFU_NAND 1530 This enables support for exposing NAND devices via DFU. 1531 1532 CONFIG_DFU_RAM 1533 This enables support for exposing RAM via DFU. 1534 Note: DFU spec refer to non-volatile memory usage, but 1535 allow usages beyond the scope of spec - here RAM usage, 1536 one that would help mostly the developer. 1537 1538 CONFIG_SYS_DFU_DATA_BUF_SIZE 1539 Dfu transfer uses a buffer before writing data to the 1540 raw storage device. Make the size (in bytes) of this buffer 1541 configurable. The size of this buffer is also configurable 1542 through the "dfu_bufsiz" environment variable. 1543 1544 CONFIG_SYS_DFU_MAX_FILE_SIZE 1545 When updating files rather than the raw storage device, 1546 we use a static buffer to copy the file into and then write 1547 the buffer once we've been given the whole file. Define 1548 this to the maximum filesize (in bytes) for the buffer. 1549 Default is 4 MiB if undefined. 1550 1551 DFU_DEFAULT_POLL_TIMEOUT 1552 Poll timeout [ms], is the timeout a device can send to the 1553 host. The host must wait for this timeout before sending 1554 a subsequent DFU_GET_STATUS request to the device. 1555 1556 DFU_MANIFEST_POLL_TIMEOUT 1557 Poll timeout [ms], which the device sends to the host when 1558 entering dfuMANIFEST state. Host waits this timeout, before 1559 sending again an USB request to the device. 1560 1561- USB Device Android Fastboot support: 1562 CONFIG_CMD_FASTBOOT 1563 This enables the command "fastboot" which enables the Android 1564 fastboot mode for the platform's USB device. Fastboot is a USB 1565 protocol for downloading images, flashing and device control 1566 used on Android devices. 1567 See doc/README.android-fastboot for more information. 1568 1569 CONFIG_ANDROID_BOOT_IMAGE 1570 This enables support for booting images which use the Android 1571 image format header. 1572 1573 CONFIG_USB_FASTBOOT_BUF_ADDR 1574 The fastboot protocol requires a large memory buffer for 1575 downloads. Define this to the starting RAM address to use for 1576 downloaded images. 1577 1578 CONFIG_USB_FASTBOOT_BUF_SIZE 1579 The fastboot protocol requires a large memory buffer for 1580 downloads. This buffer should be as large as possible for a 1581 platform. Define this to the size available RAM for fastboot. 1582 1583- Journaling Flash filesystem support: 1584 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1585 CONFIG_JFFS2_NAND_DEV 1586 Define these for a default partition on a NAND device 1587 1588 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1589 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1590 Define these for a default partition on a NOR device 1591 1592 CONFIG_SYS_JFFS_CUSTOM_PART 1593 Define this to create an own partition. You have to provide a 1594 function struct part_info* jffs2_part_info(int part_num) 1595 1596 If you define only one JFFS2 partition you may also want to 1597 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1598 to disable the command chpart. This is the default when you 1599 have not defined a custom partition 1600 1601- FAT(File Allocation Table) filesystem write function support: 1602 CONFIG_FAT_WRITE 1603 1604 Define this to enable support for saving memory data as a 1605 file in FAT formatted partition. 1606 1607 This will also enable the command "fatwrite" enabling the 1608 user to write files to FAT. 1609 1610CBFS (Coreboot Filesystem) support 1611 CONFIG_CMD_CBFS 1612 1613 Define this to enable support for reading from a Coreboot 1614 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1615 and cbfsload. 1616 1617- Keyboard Support: 1618 CONFIG_ISA_KEYBOARD 1619 1620 Define this to enable standard (PC-Style) keyboard 1621 support 1622 1623 CONFIG_I8042_KBD 1624 Standard PC keyboard driver with US (is default) and 1625 GERMAN key layout (switch via environment 'keymap=de') support. 1626 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1627 for cfb_console. Supports cursor blinking. 1628 1629 CONFIG_CROS_EC_KEYB 1630 Enables a Chrome OS keyboard using the CROS_EC interface. 1631 This uses CROS_EC to communicate with a second microcontroller 1632 which provides key scans on request. 1633 1634- Video support: 1635 CONFIG_VIDEO 1636 1637 Define this to enable video support (for output to 1638 video). 1639 1640 CONFIG_VIDEO_CT69000 1641 1642 Enable Chips & Technologies 69000 Video chip 1643 1644 CONFIG_VIDEO_SMI_LYNXEM 1645 Enable Silicon Motion SMI 712/710/810 Video chip. The 1646 video output is selected via environment 'videoout' 1647 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1648 assumed. 1649 1650 For the CT69000 and SMI_LYNXEM drivers, videomode is 1651 selected via environment 'videomode'. Two different ways 1652 are possible: 1653 - "videomode=num" 'num' is a standard LiLo mode numbers. 1654 Following standard modes are supported (* is default): 1655 1656 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1657 -------------+--------------------------------------------- 1658 8 bits | 0x301* 0x303 0x305 0x161 0x307 1659 15 bits | 0x310 0x313 0x316 0x162 0x319 1660 16 bits | 0x311 0x314 0x317 0x163 0x31A 1661 24 bits | 0x312 0x315 0x318 ? 0x31B 1662 -------------+--------------------------------------------- 1663 (i.e. setenv videomode 317; saveenv; reset;) 1664 1665 - "videomode=bootargs" all the video parameters are parsed 1666 from the bootargs. (See drivers/video/videomodes.c) 1667 1668 1669 CONFIG_VIDEO_SED13806 1670 Enable Epson SED13806 driver. This driver supports 8bpp 1671 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1672 or CONFIG_VIDEO_SED13806_16BPP 1673 1674 CONFIG_FSL_DIU_FB 1675 Enable the Freescale DIU video driver. Reference boards for 1676 SOCs that have a DIU should define this macro to enable DIU 1677 support, and should also define these other macros: 1678 1679 CONFIG_SYS_DIU_ADDR 1680 CONFIG_VIDEO 1681 CONFIG_CMD_BMP 1682 CONFIG_CFB_CONSOLE 1683 CONFIG_VIDEO_SW_CURSOR 1684 CONFIG_VGA_AS_SINGLE_DEVICE 1685 CONFIG_VIDEO_LOGO 1686 CONFIG_VIDEO_BMP_LOGO 1687 1688 The DIU driver will look for the 'video-mode' environment 1689 variable, and if defined, enable the DIU as a console during 1690 boot. See the documentation file README.video for a 1691 description of this variable. 1692 1693 CONFIG_VIDEO_VGA 1694 1695 Enable the VGA video / BIOS for x86. The alternative if you 1696 are using coreboot is to use the coreboot frame buffer 1697 driver. 1698 1699 1700- Keyboard Support: 1701 CONFIG_KEYBOARD 1702 1703 Define this to enable a custom keyboard support. 1704 This simply calls drv_keyboard_init() which must be 1705 defined in your board-specific files. 1706 The only board using this so far is RBC823. 1707 1708- LCD Support: CONFIG_LCD 1709 1710 Define this to enable LCD support (for output to LCD 1711 display); also select one of the supported displays 1712 by defining one of these: 1713 1714 CONFIG_ATMEL_LCD: 1715 1716 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1717 1718 CONFIG_NEC_NL6448AC33: 1719 1720 NEC NL6448AC33-18. Active, color, single scan. 1721 1722 CONFIG_NEC_NL6448BC20 1723 1724 NEC NL6448BC20-08. 6.5", 640x480. 1725 Active, color, single scan. 1726 1727 CONFIG_NEC_NL6448BC33_54 1728 1729 NEC NL6448BC33-54. 10.4", 640x480. 1730 Active, color, single scan. 1731 1732 CONFIG_SHARP_16x9 1733 1734 Sharp 320x240. Active, color, single scan. 1735 It isn't 16x9, and I am not sure what it is. 1736 1737 CONFIG_SHARP_LQ64D341 1738 1739 Sharp LQ64D341 display, 640x480. 1740 Active, color, single scan. 1741 1742 CONFIG_HLD1045 1743 1744 HLD1045 display, 640x480. 1745 Active, color, single scan. 1746 1747 CONFIG_OPTREX_BW 1748 1749 Optrex CBL50840-2 NF-FW 99 22 M5 1750 or 1751 Hitachi LMG6912RPFC-00T 1752 or 1753 Hitachi SP14Q002 1754 1755 320x240. Black & white. 1756 1757 Normally display is black on white background; define 1758 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1759 1760 CONFIG_LCD_ALIGNMENT 1761 1762 Normally the LCD is page-aligned (tyically 4KB). If this is 1763 defined then the LCD will be aligned to this value instead. 1764 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1765 here, since it is cheaper to change data cache settings on 1766 a per-section basis. 1767 1768 CONFIG_CONSOLE_SCROLL_LINES 1769 1770 When the console need to be scrolled, this is the number of 1771 lines to scroll by. It defaults to 1. Increasing this makes 1772 the console jump but can help speed up operation when scrolling 1773 is slow. 1774 1775 CONFIG_LCD_BMP_RLE8 1776 1777 Support drawing of RLE8-compressed bitmaps on the LCD. 1778 1779 CONFIG_I2C_EDID 1780 1781 Enables an 'i2c edid' command which can read EDID 1782 information over I2C from an attached LCD display. 1783 1784- Splash Screen Support: CONFIG_SPLASH_SCREEN 1785 1786 If this option is set, the environment is checked for 1787 a variable "splashimage". If found, the usual display 1788 of logo, copyright and system information on the LCD 1789 is suppressed and the BMP image at the address 1790 specified in "splashimage" is loaded instead. The 1791 console is redirected to the "nulldev", too. This 1792 allows for a "silent" boot where a splash screen is 1793 loaded very quickly after power-on. 1794 1795 CONFIG_SPLASHIMAGE_GUARD 1796 1797 If this option is set, then U-Boot will prevent the environment 1798 variable "splashimage" from being set to a problematic address 1799 (see README.displaying-bmps). 1800 This option is useful for targets where, due to alignment 1801 restrictions, an improperly aligned BMP image will cause a data 1802 abort. If you think you will not have problems with unaligned 1803 accesses (for example because your toolchain prevents them) 1804 there is no need to set this option. 1805 1806 CONFIG_SPLASH_SCREEN_ALIGN 1807 1808 If this option is set the splash image can be freely positioned 1809 on the screen. Environment variable "splashpos" specifies the 1810 position as "x,y". If a positive number is given it is used as 1811 number of pixel from left/top. If a negative number is given it 1812 is used as number of pixel from right/bottom. You can also 1813 specify 'm' for centering the image. 1814 1815 Example: 1816 setenv splashpos m,m 1817 => image at center of screen 1818 1819 setenv splashpos 30,20 1820 => image at x = 30 and y = 20 1821 1822 setenv splashpos -10,m 1823 => vertically centered image 1824 at x = dspWidth - bmpWidth - 9 1825 1826- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1827 1828 If this option is set, additionally to standard BMP 1829 images, gzipped BMP images can be displayed via the 1830 splashscreen support or the bmp command. 1831 1832- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1833 1834 If this option is set, 8-bit RLE compressed BMP images 1835 can be displayed via the splashscreen support or the 1836 bmp command. 1837 1838- Do compresssing for memory range: 1839 CONFIG_CMD_ZIP 1840 1841 If this option is set, it would use zlib deflate method 1842 to compress the specified memory at its best effort. 1843 1844- Compression support: 1845 CONFIG_GZIP 1846 1847 Enabled by default to support gzip compressed images. 1848 1849 CONFIG_BZIP2 1850 1851 If this option is set, support for bzip2 compressed 1852 images is included. If not, only uncompressed and gzip 1853 compressed images are supported. 1854 1855 NOTE: the bzip2 algorithm requires a lot of RAM, so 1856 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1857 be at least 4MB. 1858 1859 CONFIG_LZMA 1860 1861 If this option is set, support for lzma compressed 1862 images is included. 1863 1864 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1865 requires an amount of dynamic memory that is given by the 1866 formula: 1867 1868 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1869 1870 Where lc and lp stand for, respectively, Literal context bits 1871 and Literal pos bits. 1872 1873 This value is upper-bounded by 14MB in the worst case. Anyway, 1874 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1875 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1876 a very small buffer. 1877 1878 Use the lzmainfo tool to determinate the lc and lp values and 1879 then calculate the amount of needed dynamic memory (ensuring 1880 the appropriate CONFIG_SYS_MALLOC_LEN value). 1881 1882 CONFIG_LZO 1883 1884 If this option is set, support for LZO compressed images 1885 is included. 1886 1887- MII/PHY support: 1888 CONFIG_PHY_ADDR 1889 1890 The address of PHY on MII bus. 1891 1892 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1893 1894 The clock frequency of the MII bus 1895 1896 CONFIG_PHY_GIGE 1897 1898 If this option is set, support for speed/duplex 1899 detection of gigabit PHY is included. 1900 1901 CONFIG_PHY_RESET_DELAY 1902 1903 Some PHY like Intel LXT971A need extra delay after 1904 reset before any MII register access is possible. 1905 For such PHY, set this option to the usec delay 1906 required. (minimum 300usec for LXT971A) 1907 1908 CONFIG_PHY_CMD_DELAY (ppc4xx) 1909 1910 Some PHY like Intel LXT971A need extra delay after 1911 command issued before MII status register can be read 1912 1913- Ethernet address: 1914 CONFIG_ETHADDR 1915 CONFIG_ETH1ADDR 1916 CONFIG_ETH2ADDR 1917 CONFIG_ETH3ADDR 1918 CONFIG_ETH4ADDR 1919 CONFIG_ETH5ADDR 1920 1921 Define a default value for Ethernet address to use 1922 for the respective Ethernet interface, in case this 1923 is not determined automatically. 1924 1925- IP address: 1926 CONFIG_IPADDR 1927 1928 Define a default value for the IP address to use for 1929 the default Ethernet interface, in case this is not 1930 determined through e.g. bootp. 1931 (Environment variable "ipaddr") 1932 1933- Server IP address: 1934 CONFIG_SERVERIP 1935 1936 Defines a default value for the IP address of a TFTP 1937 server to contact when using the "tftboot" command. 1938 (Environment variable "serverip") 1939 1940 CONFIG_KEEP_SERVERADDR 1941 1942 Keeps the server's MAC address, in the env 'serveraddr' 1943 for passing to bootargs (like Linux's netconsole option) 1944 1945- Gateway IP address: 1946 CONFIG_GATEWAYIP 1947 1948 Defines a default value for the IP address of the 1949 default router where packets to other networks are 1950 sent to. 1951 (Environment variable "gatewayip") 1952 1953- Subnet mask: 1954 CONFIG_NETMASK 1955 1956 Defines a default value for the subnet mask (or 1957 routing prefix) which is used to determine if an IP 1958 address belongs to the local subnet or needs to be 1959 forwarded through a router. 1960 (Environment variable "netmask") 1961 1962- Multicast TFTP Mode: 1963 CONFIG_MCAST_TFTP 1964 1965 Defines whether you want to support multicast TFTP as per 1966 rfc-2090; for example to work with atftp. Lets lots of targets 1967 tftp down the same boot image concurrently. Note: the Ethernet 1968 driver in use must provide a function: mcast() to join/leave a 1969 multicast group. 1970 1971- BOOTP Recovery Mode: 1972 CONFIG_BOOTP_RANDOM_DELAY 1973 1974 If you have many targets in a network that try to 1975 boot using BOOTP, you may want to avoid that all 1976 systems send out BOOTP requests at precisely the same 1977 moment (which would happen for instance at recovery 1978 from a power failure, when all systems will try to 1979 boot, thus flooding the BOOTP server. Defining 1980 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1981 inserted before sending out BOOTP requests. The 1982 following delays are inserted then: 1983 1984 1st BOOTP request: delay 0 ... 1 sec 1985 2nd BOOTP request: delay 0 ... 2 sec 1986 3rd BOOTP request: delay 0 ... 4 sec 1987 4th and following 1988 BOOTP requests: delay 0 ... 8 sec 1989 1990- DHCP Advanced Options: 1991 You can fine tune the DHCP functionality by defining 1992 CONFIG_BOOTP_* symbols: 1993 1994 CONFIG_BOOTP_SUBNETMASK 1995 CONFIG_BOOTP_GATEWAY 1996 CONFIG_BOOTP_HOSTNAME 1997 CONFIG_BOOTP_NISDOMAIN 1998 CONFIG_BOOTP_BOOTPATH 1999 CONFIG_BOOTP_BOOTFILESIZE 2000 CONFIG_BOOTP_DNS 2001 CONFIG_BOOTP_DNS2 2002 CONFIG_BOOTP_SEND_HOSTNAME 2003 CONFIG_BOOTP_NTPSERVER 2004 CONFIG_BOOTP_TIMEOFFSET 2005 CONFIG_BOOTP_VENDOREX 2006 CONFIG_BOOTP_MAY_FAIL 2007 2008 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 2009 environment variable, not the BOOTP server. 2010 2011 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 2012 after the configured retry count, the call will fail 2013 instead of starting over. This can be used to fail over 2014 to Link-local IP address configuration if the DHCP server 2015 is not available. 2016 2017 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 2018 serverip from a DHCP server, it is possible that more 2019 than one DNS serverip is offered to the client. 2020 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 2021 serverip will be stored in the additional environment 2022 variable "dnsip2". The first DNS serverip is always 2023 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 2024 is defined. 2025 2026 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 2027 to do a dynamic update of a DNS server. To do this, they 2028 need the hostname of the DHCP requester. 2029 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 2030 of the "hostname" environment variable is passed as 2031 option 12 to the DHCP server. 2032 2033 CONFIG_BOOTP_DHCP_REQUEST_DELAY 2034 2035 A 32bit value in microseconds for a delay between 2036 receiving a "DHCP Offer" and sending the "DHCP Request". 2037 This fixes a problem with certain DHCP servers that don't 2038 respond 100% of the time to a "DHCP request". E.g. On an 2039 AT91RM9200 processor running at 180MHz, this delay needed 2040 to be *at least* 15,000 usec before a Windows Server 2003 2041 DHCP server would reply 100% of the time. I recommend at 2042 least 50,000 usec to be safe. The alternative is to hope 2043 that one of the retries will be successful but note that 2044 the DHCP timeout and retry process takes a longer than 2045 this delay. 2046 2047 - Link-local IP address negotiation: 2048 Negotiate with other link-local clients on the local network 2049 for an address that doesn't require explicit configuration. 2050 This is especially useful if a DHCP server cannot be guaranteed 2051 to exist in all environments that the device must operate. 2052 2053 See doc/README.link-local for more information. 2054 2055 - CDP Options: 2056 CONFIG_CDP_DEVICE_ID 2057 2058 The device id used in CDP trigger frames. 2059 2060 CONFIG_CDP_DEVICE_ID_PREFIX 2061 2062 A two character string which is prefixed to the MAC address 2063 of the device. 2064 2065 CONFIG_CDP_PORT_ID 2066 2067 A printf format string which contains the ascii name of 2068 the port. Normally is set to "eth%d" which sets 2069 eth0 for the first Ethernet, eth1 for the second etc. 2070 2071 CONFIG_CDP_CAPABILITIES 2072 2073 A 32bit integer which indicates the device capabilities; 2074 0x00000010 for a normal host which does not forwards. 2075 2076 CONFIG_CDP_VERSION 2077 2078 An ascii string containing the version of the software. 2079 2080 CONFIG_CDP_PLATFORM 2081 2082 An ascii string containing the name of the platform. 2083 2084 CONFIG_CDP_TRIGGER 2085 2086 A 32bit integer sent on the trigger. 2087 2088 CONFIG_CDP_POWER_CONSUMPTION 2089 2090 A 16bit integer containing the power consumption of the 2091 device in .1 of milliwatts. 2092 2093 CONFIG_CDP_APPLIANCE_VLAN_TYPE 2094 2095 A byte containing the id of the VLAN. 2096 2097- Status LED: CONFIG_STATUS_LED 2098 2099 Several configurations allow to display the current 2100 status using a LED. For instance, the LED will blink 2101 fast while running U-Boot code, stop blinking as 2102 soon as a reply to a BOOTP request was received, and 2103 start blinking slow once the Linux kernel is running 2104 (supported by a status LED driver in the Linux 2105 kernel). Defining CONFIG_STATUS_LED enables this 2106 feature in U-Boot. 2107 2108 Additional options: 2109 2110 CONFIG_GPIO_LED 2111 The status LED can be connected to a GPIO pin. 2112 In such cases, the gpio_led driver can be used as a 2113 status LED backend implementation. Define CONFIG_GPIO_LED 2114 to include the gpio_led driver in the U-Boot binary. 2115 2116 CONFIG_GPIO_LED_INVERTED_TABLE 2117 Some GPIO connected LEDs may have inverted polarity in which 2118 case the GPIO high value corresponds to LED off state and 2119 GPIO low value corresponds to LED on state. 2120 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2121 with a list of GPIO LEDs that have inverted polarity. 2122 2123- CAN Support: CONFIG_CAN_DRIVER 2124 2125 Defining CONFIG_CAN_DRIVER enables CAN driver support 2126 on those systems that support this (optional) 2127 feature, like the TQM8xxL modules. 2128 2129- I2C Support: CONFIG_SYS_I2C 2130 2131 This enable the NEW i2c subsystem, and will allow you to use 2132 i2c commands at the u-boot command line (as long as you set 2133 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2134 based realtime clock chips or other i2c devices. See 2135 common/cmd_i2c.c for a description of the command line 2136 interface. 2137 2138 ported i2c driver to the new framework: 2139 - drivers/i2c/soft_i2c.c: 2140 - activate first bus with CONFIG_SYS_I2C_SOFT define 2141 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2142 for defining speed and slave address 2143 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2144 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2145 for defining speed and slave address 2146 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2147 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2148 for defining speed and slave address 2149 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2150 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2151 for defining speed and slave address 2152 2153 - drivers/i2c/fsl_i2c.c: 2154 - activate i2c driver with CONFIG_SYS_I2C_FSL 2155 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2156 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2157 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2158 bus. 2159 - If your board supports a second fsl i2c bus, define 2160 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2161 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2162 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2163 second bus. 2164 2165 - drivers/i2c/tegra_i2c.c: 2166 - activate this driver with CONFIG_SYS_I2C_TEGRA 2167 - This driver adds 4 i2c buses with a fix speed from 2168 100000 and the slave addr 0! 2169 2170 - drivers/i2c/ppc4xx_i2c.c 2171 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2172 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2173 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2174 2175 - drivers/i2c/i2c_mxc.c 2176 - activate this driver with CONFIG_SYS_I2C_MXC 2177 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2178 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2179 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2180 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2181 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2182 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2183 If thoses defines are not set, default value is 100000 2184 for speed, and 0 for slave. 2185 2186 - drivers/i2c/rcar_i2c.c: 2187 - activate this driver with CONFIG_SYS_I2C_RCAR 2188 - This driver adds 4 i2c buses 2189 2190 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2191 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2192 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2193 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2194 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2195 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2196 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2197 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2198 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2199 2200 - drivers/i2c/sh_i2c.c: 2201 - activate this driver with CONFIG_SYS_I2C_SH 2202 - This driver adds from 2 to 5 i2c buses 2203 2204 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2205 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2206 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2207 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2208 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2209 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2210 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2211 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2212 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2213 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2214 - CONFIG_SYS_I2C_SH_BASE5 for setting the register channel 5 2215 - CONFIG_SYS_I2C_SH_SPEED5 for for the speed channel 5 2216 - CONFIF_SYS_I2C_SH_NUM_CONTROLLERS for nummber of i2c buses 2217 2218 - drivers/i2c/omap24xx_i2c.c 2219 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2220 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2221 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2222 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2223 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2224 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2225 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2226 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2227 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2228 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2229 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2230 2231 - drivers/i2c/zynq_i2c.c 2232 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2233 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2234 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2235 2236 - drivers/i2c/s3c24x0_i2c.c: 2237 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2238 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2239 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2240 with a fix speed from 100000 and the slave addr 0! 2241 2242 additional defines: 2243 2244 CONFIG_SYS_NUM_I2C_BUSES 2245 Hold the number of i2c busses you want to use. If you 2246 don't use/have i2c muxes on your i2c bus, this 2247 is equal to CONFIG_SYS_NUM_I2C_ADAPTERS, and you can 2248 omit this define. 2249 2250 CONFIG_SYS_I2C_DIRECT_BUS 2251 define this, if you don't use i2c muxes on your hardware. 2252 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2253 omit this define. 2254 2255 CONFIG_SYS_I2C_MAX_HOPS 2256 define how many muxes are maximal consecutively connected 2257 on one i2c bus. If you not use i2c muxes, omit this 2258 define. 2259 2260 CONFIG_SYS_I2C_BUSES 2261 hold a list of busses you want to use, only used if 2262 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2263 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2264 CONFIG_SYS_NUM_I2C_BUSES = 9: 2265 2266 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2267 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2268 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2269 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2270 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2271 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2272 {1, {I2C_NULL_HOP}}, \ 2273 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2274 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2275 } 2276 2277 which defines 2278 bus 0 on adapter 0 without a mux 2279 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2280 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2281 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2282 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2283 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2284 bus 6 on adapter 1 without a mux 2285 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2286 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2287 2288 If you do not have i2c muxes on your board, omit this define. 2289 2290- Legacy I2C Support: CONFIG_HARD_I2C 2291 2292 NOTE: It is intended to move drivers to CONFIG_SYS_I2C which 2293 provides the following compelling advantages: 2294 2295 - more than one i2c adapter is usable 2296 - approved multibus support 2297 - better i2c mux support 2298 2299 ** Please consider updating your I2C driver now. ** 2300 2301 These enable legacy I2C serial bus commands. Defining 2302 CONFIG_HARD_I2C will include the appropriate I2C driver 2303 for the selected CPU. 2304 2305 This will allow you to use i2c commands at the u-boot 2306 command line (as long as you set CONFIG_CMD_I2C in 2307 CONFIG_COMMANDS) and communicate with i2c based realtime 2308 clock chips. See common/cmd_i2c.c for a description of the 2309 command line interface. 2310 2311 CONFIG_HARD_I2C selects a hardware I2C controller. 2312 2313 There are several other quantities that must also be 2314 defined when you define CONFIG_HARD_I2C. 2315 2316 In both cases you will need to define CONFIG_SYS_I2C_SPEED 2317 to be the frequency (in Hz) at which you wish your i2c bus 2318 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 2319 the CPU's i2c node address). 2320 2321 Now, the u-boot i2c code for the mpc8xx 2322 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 2323 and so its address should therefore be cleared to 0 (See, 2324 eg, MPC823e User's Manual p.16-473). So, set 2325 CONFIG_SYS_I2C_SLAVE to 0. 2326 2327 CONFIG_SYS_I2C_INIT_MPC5XXX 2328 2329 When a board is reset during an i2c bus transfer 2330 chips might think that the current transfer is still 2331 in progress. Reset the slave devices by sending start 2332 commands until the slave device responds. 2333 2334 That's all that's required for CONFIG_HARD_I2C. 2335 2336 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2337 then the following macros need to be defined (examples are 2338 from include/configs/lwmon.h): 2339 2340 I2C_INIT 2341 2342 (Optional). Any commands necessary to enable the I2C 2343 controller or configure ports. 2344 2345 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2346 2347 I2C_PORT 2348 2349 (Only for MPC8260 CPU). The I/O port to use (the code 2350 assumes both bits are on the same port). Valid values 2351 are 0..3 for ports A..D. 2352 2353 I2C_ACTIVE 2354 2355 The code necessary to make the I2C data line active 2356 (driven). If the data line is open collector, this 2357 define can be null. 2358 2359 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2360 2361 I2C_TRISTATE 2362 2363 The code necessary to make the I2C data line tri-stated 2364 (inactive). If the data line is open collector, this 2365 define can be null. 2366 2367 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2368 2369 I2C_READ 2370 2371 Code that returns true if the I2C data line is high, 2372 false if it is low. 2373 2374 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2375 2376 I2C_SDA(bit) 2377 2378 If <bit> is true, sets the I2C data line high. If it 2379 is false, it clears it (low). 2380 2381 eg: #define I2C_SDA(bit) \ 2382 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2383 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2384 2385 I2C_SCL(bit) 2386 2387 If <bit> is true, sets the I2C clock line high. If it 2388 is false, it clears it (low). 2389 2390 eg: #define I2C_SCL(bit) \ 2391 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2392 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2393 2394 I2C_DELAY 2395 2396 This delay is invoked four times per clock cycle so this 2397 controls the rate of data transfer. The data rate thus 2398 is 1 / (I2C_DELAY * 4). Often defined to be something 2399 like: 2400 2401 #define I2C_DELAY udelay(2) 2402 2403 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2404 2405 If your arch supports the generic GPIO framework (asm/gpio.h), 2406 then you may alternatively define the two GPIOs that are to be 2407 used as SCL / SDA. Any of the previous I2C_xxx macros will 2408 have GPIO-based defaults assigned to them as appropriate. 2409 2410 You should define these to the GPIO value as given directly to 2411 the generic GPIO functions. 2412 2413 CONFIG_SYS_I2C_INIT_BOARD 2414 2415 When a board is reset during an i2c bus transfer 2416 chips might think that the current transfer is still 2417 in progress. On some boards it is possible to access 2418 the i2c SCLK line directly, either by using the 2419 processor pin as a GPIO or by having a second pin 2420 connected to the bus. If this option is defined a 2421 custom i2c_init_board() routine in boards/xxx/board.c 2422 is run early in the boot sequence. 2423 2424 CONFIG_SYS_I2C_BOARD_LATE_INIT 2425 2426 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2427 defined a custom i2c_board_late_init() routine in 2428 boards/xxx/board.c is run AFTER the operations in i2c_init() 2429 is completed. This callpoint can be used to unreset i2c bus 2430 using CPU i2c controller register accesses for CPUs whose i2c 2431 controller provide such a method. It is called at the end of 2432 i2c_init() to allow i2c_init operations to setup the i2c bus 2433 controller on the CPU (e.g. setting bus speed & slave address). 2434 2435 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2436 2437 This option enables configuration of bi_iic_fast[] flags 2438 in u-boot bd_info structure based on u-boot environment 2439 variable "i2cfast". (see also i2cfast) 2440 2441 CONFIG_I2C_MULTI_BUS 2442 2443 This option allows the use of multiple I2C buses, each of which 2444 must have a controller. At any point in time, only one bus is 2445 active. To switch to a different bus, use the 'i2c dev' command. 2446 Note that bus numbering is zero-based. 2447 2448 CONFIG_SYS_I2C_NOPROBES 2449 2450 This option specifies a list of I2C devices that will be skipped 2451 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2452 is set, specify a list of bus-device pairs. Otherwise, specify 2453 a 1D array of device addresses 2454 2455 e.g. 2456 #undef CONFIG_I2C_MULTI_BUS 2457 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2458 2459 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2460 2461 #define CONFIG_I2C_MULTI_BUS 2462 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2463 2464 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2465 2466 CONFIG_SYS_SPD_BUS_NUM 2467 2468 If defined, then this indicates the I2C bus number for DDR SPD. 2469 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2470 2471 CONFIG_SYS_RTC_BUS_NUM 2472 2473 If defined, then this indicates the I2C bus number for the RTC. 2474 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2475 2476 CONFIG_SYS_DTT_BUS_NUM 2477 2478 If defined, then this indicates the I2C bus number for the DTT. 2479 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2480 2481 CONFIG_SYS_I2C_DTT_ADDR: 2482 2483 If defined, specifies the I2C address of the DTT device. 2484 If not defined, then U-Boot uses predefined value for 2485 specified DTT device. 2486 2487 CONFIG_SOFT_I2C_READ_REPEATED_START 2488 2489 defining this will force the i2c_read() function in 2490 the soft_i2c driver to perform an I2C repeated start 2491 between writing the address pointer and reading the 2492 data. If this define is omitted the default behaviour 2493 of doing a stop-start sequence will be used. Most I2C 2494 devices can use either method, but some require one or 2495 the other. 2496 2497- SPI Support: CONFIG_SPI 2498 2499 Enables SPI driver (so far only tested with 2500 SPI EEPROM, also an instance works with Crystal A/D and 2501 D/As on the SACSng board) 2502 2503 CONFIG_SH_SPI 2504 2505 Enables the driver for SPI controller on SuperH. Currently 2506 only SH7757 is supported. 2507 2508 CONFIG_SPI_X 2509 2510 Enables extended (16-bit) SPI EEPROM addressing. 2511 (symmetrical to CONFIG_I2C_X) 2512 2513 CONFIG_SOFT_SPI 2514 2515 Enables a software (bit-bang) SPI driver rather than 2516 using hardware support. This is a general purpose 2517 driver that only requires three general I/O port pins 2518 (two outputs, one input) to function. If this is 2519 defined, the board configuration must define several 2520 SPI configuration items (port pins to use, etc). For 2521 an example, see include/configs/sacsng.h. 2522 2523 CONFIG_HARD_SPI 2524 2525 Enables a hardware SPI driver for general-purpose reads 2526 and writes. As with CONFIG_SOFT_SPI, the board configuration 2527 must define a list of chip-select function pointers. 2528 Currently supported on some MPC8xxx processors. For an 2529 example, see include/configs/mpc8349emds.h. 2530 2531 CONFIG_MXC_SPI 2532 2533 Enables the driver for the SPI controllers on i.MX and MXC 2534 SoCs. Currently i.MX31/35/51 are supported. 2535 2536- FPGA Support: CONFIG_FPGA 2537 2538 Enables FPGA subsystem. 2539 2540 CONFIG_FPGA_<vendor> 2541 2542 Enables support for specific chip vendors. 2543 (ALTERA, XILINX) 2544 2545 CONFIG_FPGA_<family> 2546 2547 Enables support for FPGA family. 2548 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2549 2550 CONFIG_FPGA_COUNT 2551 2552 Specify the number of FPGA devices to support. 2553 2554 CONFIG_SYS_FPGA_PROG_FEEDBACK 2555 2556 Enable printing of hash marks during FPGA configuration. 2557 2558 CONFIG_SYS_FPGA_CHECK_BUSY 2559 2560 Enable checks on FPGA configuration interface busy 2561 status by the configuration function. This option 2562 will require a board or device specific function to 2563 be written. 2564 2565 CONFIG_FPGA_DELAY 2566 2567 If defined, a function that provides delays in the FPGA 2568 configuration driver. 2569 2570 CONFIG_SYS_FPGA_CHECK_CTRLC 2571 Allow Control-C to interrupt FPGA configuration 2572 2573 CONFIG_SYS_FPGA_CHECK_ERROR 2574 2575 Check for configuration errors during FPGA bitfile 2576 loading. For example, abort during Virtex II 2577 configuration if the INIT_B line goes low (which 2578 indicated a CRC error). 2579 2580 CONFIG_SYS_FPGA_WAIT_INIT 2581 2582 Maximum time to wait for the INIT_B line to deassert 2583 after PROB_B has been deasserted during a Virtex II 2584 FPGA configuration sequence. The default time is 500 2585 ms. 2586 2587 CONFIG_SYS_FPGA_WAIT_BUSY 2588 2589 Maximum time to wait for BUSY to deassert during 2590 Virtex II FPGA configuration. The default is 5 ms. 2591 2592 CONFIG_SYS_FPGA_WAIT_CONFIG 2593 2594 Time to wait after FPGA configuration. The default is 2595 200 ms. 2596 2597- Configuration Management: 2598 CONFIG_IDENT_STRING 2599 2600 If defined, this string will be added to the U-Boot 2601 version information (U_BOOT_VERSION) 2602 2603- Vendor Parameter Protection: 2604 2605 U-Boot considers the values of the environment 2606 variables "serial#" (Board Serial Number) and 2607 "ethaddr" (Ethernet Address) to be parameters that 2608 are set once by the board vendor / manufacturer, and 2609 protects these variables from casual modification by 2610 the user. Once set, these variables are read-only, 2611 and write or delete attempts are rejected. You can 2612 change this behaviour: 2613 2614 If CONFIG_ENV_OVERWRITE is #defined in your config 2615 file, the write protection for vendor parameters is 2616 completely disabled. Anybody can change or delete 2617 these parameters. 2618 2619 Alternatively, if you #define _both_ CONFIG_ETHADDR 2620 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2621 Ethernet address is installed in the environment, 2622 which can be changed exactly ONCE by the user. [The 2623 serial# is unaffected by this, i. e. it remains 2624 read-only.] 2625 2626 The same can be accomplished in a more flexible way 2627 for any variable by configuring the type of access 2628 to allow for those variables in the ".flags" variable 2629 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2630 2631- Protected RAM: 2632 CONFIG_PRAM 2633 2634 Define this variable to enable the reservation of 2635 "protected RAM", i. e. RAM which is not overwritten 2636 by U-Boot. Define CONFIG_PRAM to hold the number of 2637 kB you want to reserve for pRAM. You can overwrite 2638 this default value by defining an environment 2639 variable "pram" to the number of kB you want to 2640 reserve. Note that the board info structure will 2641 still show the full amount of RAM. If pRAM is 2642 reserved, a new environment variable "mem" will 2643 automatically be defined to hold the amount of 2644 remaining RAM in a form that can be passed as boot 2645 argument to Linux, for instance like that: 2646 2647 setenv bootargs ... mem=\${mem} 2648 saveenv 2649 2650 This way you can tell Linux not to use this memory, 2651 either, which results in a memory region that will 2652 not be affected by reboots. 2653 2654 *WARNING* If your board configuration uses automatic 2655 detection of the RAM size, you must make sure that 2656 this memory test is non-destructive. So far, the 2657 following board configurations are known to be 2658 "pRAM-clean": 2659 2660 IVMS8, IVML24, SPD8xx, TQM8xxL, 2661 HERMES, IP860, RPXlite, LWMON, 2662 FLAGADM, TQM8260 2663 2664- Access to physical memory region (> 4GB) 2665 Some basic support is provided for operations on memory not 2666 normally accessible to U-Boot - e.g. some architectures 2667 support access to more than 4GB of memory on 32-bit 2668 machines using physical address extension or similar. 2669 Define CONFIG_PHYSMEM to access this basic support, which 2670 currently only supports clearing the memory. 2671 2672- Error Recovery: 2673 CONFIG_PANIC_HANG 2674 2675 Define this variable to stop the system in case of a 2676 fatal error, so that you have to reset it manually. 2677 This is probably NOT a good idea for an embedded 2678 system where you want the system to reboot 2679 automatically as fast as possible, but it may be 2680 useful during development since you can try to debug 2681 the conditions that lead to the situation. 2682 2683 CONFIG_NET_RETRY_COUNT 2684 2685 This variable defines the number of retries for 2686 network operations like ARP, RARP, TFTP, or BOOTP 2687 before giving up the operation. If not defined, a 2688 default value of 5 is used. 2689 2690 CONFIG_ARP_TIMEOUT 2691 2692 Timeout waiting for an ARP reply in milliseconds. 2693 2694 CONFIG_NFS_TIMEOUT 2695 2696 Timeout in milliseconds used in NFS protocol. 2697 If you encounter "ERROR: Cannot umount" in nfs command, 2698 try longer timeout such as 2699 #define CONFIG_NFS_TIMEOUT 10000UL 2700 2701- Command Interpreter: 2702 CONFIG_AUTO_COMPLETE 2703 2704 Enable auto completion of commands using TAB. 2705 2706 Note that this feature has NOT been implemented yet 2707 for the "hush" shell. 2708 2709 2710 CONFIG_SYS_HUSH_PARSER 2711 2712 Define this variable to enable the "hush" shell (from 2713 Busybox) as command line interpreter, thus enabling 2714 powerful command line syntax like 2715 if...then...else...fi conditionals or `&&' and '||' 2716 constructs ("shell scripts"). 2717 2718 If undefined, you get the old, much simpler behaviour 2719 with a somewhat smaller memory footprint. 2720 2721 2722 CONFIG_SYS_PROMPT_HUSH_PS2 2723 2724 This defines the secondary prompt string, which is 2725 printed when the command interpreter needs more input 2726 to complete a command. Usually "> ". 2727 2728 Note: 2729 2730 In the current implementation, the local variables 2731 space and global environment variables space are 2732 separated. Local variables are those you define by 2733 simply typing `name=value'. To access a local 2734 variable later on, you have write `$name' or 2735 `${name}'; to execute the contents of a variable 2736 directly type `$name' at the command prompt. 2737 2738 Global environment variables are those you use 2739 setenv/printenv to work with. To run a command stored 2740 in such a variable, you need to use the run command, 2741 and you must not use the '$' sign to access them. 2742 2743 To store commands and special characters in a 2744 variable, please use double quotation marks 2745 surrounding the whole text of the variable, instead 2746 of the backslashes before semicolons and special 2747 symbols. 2748 2749- Commandline Editing and History: 2750 CONFIG_CMDLINE_EDITING 2751 2752 Enable editing and History functions for interactive 2753 commandline input operations 2754 2755- Default Environment: 2756 CONFIG_EXTRA_ENV_SETTINGS 2757 2758 Define this to contain any number of null terminated 2759 strings (variable = value pairs) that will be part of 2760 the default environment compiled into the boot image. 2761 2762 For example, place something like this in your 2763 board's config file: 2764 2765 #define CONFIG_EXTRA_ENV_SETTINGS \ 2766 "myvar1=value1\0" \ 2767 "myvar2=value2\0" 2768 2769 Warning: This method is based on knowledge about the 2770 internal format how the environment is stored by the 2771 U-Boot code. This is NOT an official, exported 2772 interface! Although it is unlikely that this format 2773 will change soon, there is no guarantee either. 2774 You better know what you are doing here. 2775 2776 Note: overly (ab)use of the default environment is 2777 discouraged. Make sure to check other ways to preset 2778 the environment like the "source" command or the 2779 boot command first. 2780 2781 CONFIG_ENV_VARS_UBOOT_CONFIG 2782 2783 Define this in order to add variables describing the 2784 U-Boot build configuration to the default environment. 2785 These will be named arch, cpu, board, vendor, and soc. 2786 2787 Enabling this option will cause the following to be defined: 2788 2789 - CONFIG_SYS_ARCH 2790 - CONFIG_SYS_CPU 2791 - CONFIG_SYS_BOARD 2792 - CONFIG_SYS_VENDOR 2793 - CONFIG_SYS_SOC 2794 2795 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2796 2797 Define this in order to add variables describing certain 2798 run-time determined information about the hardware to the 2799 environment. These will be named board_name, board_rev. 2800 2801 CONFIG_DELAY_ENVIRONMENT 2802 2803 Normally the environment is loaded when the board is 2804 intialised so that it is available to U-Boot. This inhibits 2805 that so that the environment is not available until 2806 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2807 this is instead controlled by the value of 2808 /config/load-environment. 2809 2810- DataFlash Support: 2811 CONFIG_HAS_DATAFLASH 2812 2813 Defining this option enables DataFlash features and 2814 allows to read/write in Dataflash via the standard 2815 commands cp, md... 2816 2817- Serial Flash support 2818 CONFIG_CMD_SF 2819 2820 Defining this option enables SPI flash commands 2821 'sf probe/read/write/erase/update'. 2822 2823 Usage requires an initial 'probe' to define the serial 2824 flash parameters, followed by read/write/erase/update 2825 commands. 2826 2827 The following defaults may be provided by the platform 2828 to handle the common case when only a single serial 2829 flash is present on the system. 2830 2831 CONFIG_SF_DEFAULT_BUS Bus identifier 2832 CONFIG_SF_DEFAULT_CS Chip-select 2833 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2834 CONFIG_SF_DEFAULT_SPEED in Hz 2835 2836 CONFIG_CMD_SF_TEST 2837 2838 Define this option to include a destructive SPI flash 2839 test ('sf test'). 2840 2841 CONFIG_SPI_FLASH_BAR Ban/Extended Addr Reg 2842 2843 Define this option to use the Bank addr/Extended addr 2844 support on SPI flashes which has size > 16Mbytes. 2845 2846 CONFIG_SF_DUAL_FLASH Dual flash memories 2847 2848 Define this option to use dual flash support where two flash 2849 memories can be connected with a given cs line. 2850 currently Xilinx Zynq qspi support these type of connections. 2851 2852- SystemACE Support: 2853 CONFIG_SYSTEMACE 2854 2855 Adding this option adds support for Xilinx SystemACE 2856 chips attached via some sort of local bus. The address 2857 of the chip must also be defined in the 2858 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2859 2860 #define CONFIG_SYSTEMACE 2861 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2862 2863 When SystemACE support is added, the "ace" device type 2864 becomes available to the fat commands, i.e. fatls. 2865 2866- TFTP Fixed UDP Port: 2867 CONFIG_TFTP_PORT 2868 2869 If this is defined, the environment variable tftpsrcp 2870 is used to supply the TFTP UDP source port value. 2871 If tftpsrcp isn't defined, the normal pseudo-random port 2872 number generator is used. 2873 2874 Also, the environment variable tftpdstp is used to supply 2875 the TFTP UDP destination port value. If tftpdstp isn't 2876 defined, the normal port 69 is used. 2877 2878 The purpose for tftpsrcp is to allow a TFTP server to 2879 blindly start the TFTP transfer using the pre-configured 2880 target IP address and UDP port. This has the effect of 2881 "punching through" the (Windows XP) firewall, allowing 2882 the remainder of the TFTP transfer to proceed normally. 2883 A better solution is to properly configure the firewall, 2884 but sometimes that is not allowed. 2885 2886- Hashing support: 2887 CONFIG_CMD_HASH 2888 2889 This enables a generic 'hash' command which can produce 2890 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2891 2892 CONFIG_HASH_VERIFY 2893 2894 Enable the hash verify command (hash -v). This adds to code 2895 size a little. 2896 2897 CONFIG_SHA1 - support SHA1 hashing 2898 CONFIG_SHA256 - support SHA256 hashing 2899 2900 Note: There is also a sha1sum command, which should perhaps 2901 be deprecated in favour of 'hash sha1'. 2902 2903- Freescale i.MX specific commands: 2904 CONFIG_CMD_HDMIDETECT 2905 This enables 'hdmidet' command which returns true if an 2906 HDMI monitor is detected. This command is i.MX 6 specific. 2907 2908 CONFIG_CMD_BMODE 2909 This enables the 'bmode' (bootmode) command for forcing 2910 a boot from specific media. 2911 2912 This is useful for forcing the ROM's usb downloader to 2913 activate upon a watchdog reset which is nice when iterating 2914 on U-Boot. Using the reset button or running bmode normal 2915 will set it back to normal. This command currently 2916 supports i.MX53 and i.MX6. 2917 2918- Signing support: 2919 CONFIG_RSA 2920 2921 This enables the RSA algorithm used for FIT image verification 2922 in U-Boot. See doc/uImage.FIT/signature.txt for more information. 2923 2924 The signing part is build into mkimage regardless of this 2925 option. 2926 2927- bootcount support: 2928 CONFIG_BOOTCOUNT_LIMIT 2929 2930 This enables the bootcounter support, see: 2931 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2932 2933 CONFIG_AT91SAM9XE 2934 enable special bootcounter support on at91sam9xe based boards. 2935 CONFIG_BLACKFIN 2936 enable special bootcounter support on blackfin based boards. 2937 CONFIG_SOC_DA8XX 2938 enable special bootcounter support on da850 based boards. 2939 CONFIG_BOOTCOUNT_RAM 2940 enable support for the bootcounter in RAM 2941 CONFIG_BOOTCOUNT_I2C 2942 enable support for the bootcounter on an i2c (like RTC) device. 2943 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2944 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2945 the bootcounter. 2946 CONFIG_BOOTCOUNT_ALEN = address len 2947 2948- Show boot progress: 2949 CONFIG_SHOW_BOOT_PROGRESS 2950 2951 Defining this option allows to add some board- 2952 specific code (calling a user-provided function 2953 "show_boot_progress(int)") that enables you to show 2954 the system's boot progress on some display (for 2955 example, some LED's) on your board. At the moment, 2956 the following checkpoints are implemented: 2957 2958- Detailed boot stage timing 2959 CONFIG_BOOTSTAGE 2960 Define this option to get detailed timing of each stage 2961 of the boot process. 2962 2963 CONFIG_BOOTSTAGE_USER_COUNT 2964 This is the number of available user bootstage records. 2965 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 2966 a new ID will be allocated from this stash. If you exceed 2967 the limit, recording will stop. 2968 2969 CONFIG_BOOTSTAGE_REPORT 2970 Define this to print a report before boot, similar to this: 2971 2972 Timer summary in microseconds: 2973 Mark Elapsed Stage 2974 0 0 reset 2975 3,575,678 3,575,678 board_init_f start 2976 3,575,695 17 arch_cpu_init A9 2977 3,575,777 82 arch_cpu_init done 2978 3,659,598 83,821 board_init_r start 2979 3,910,375 250,777 main_loop 2980 29,916,167 26,005,792 bootm_start 2981 30,361,327 445,160 start_kernel 2982 2983 CONFIG_CMD_BOOTSTAGE 2984 Add a 'bootstage' command which supports printing a report 2985 and un/stashing of bootstage data. 2986 2987 CONFIG_BOOTSTAGE_FDT 2988 Stash the bootstage information in the FDT. A root 'bootstage' 2989 node is created with each bootstage id as a child. Each child 2990 has a 'name' property and either 'mark' containing the 2991 mark time in microsecond, or 'accum' containing the 2992 accumulated time for that bootstage id in microseconds. 2993 For example: 2994 2995 bootstage { 2996 154 { 2997 name = "board_init_f"; 2998 mark = <3575678>; 2999 }; 3000 170 { 3001 name = "lcd"; 3002 accum = <33482>; 3003 }; 3004 }; 3005 3006 Code in the Linux kernel can find this in /proc/devicetree. 3007 3008Legacy uImage format: 3009 3010 Arg Where When 3011 1 common/cmd_bootm.c before attempting to boot an image 3012 -1 common/cmd_bootm.c Image header has bad magic number 3013 2 common/cmd_bootm.c Image header has correct magic number 3014 -2 common/cmd_bootm.c Image header has bad checksum 3015 3 common/cmd_bootm.c Image header has correct checksum 3016 -3 common/cmd_bootm.c Image data has bad checksum 3017 4 common/cmd_bootm.c Image data has correct checksum 3018 -4 common/cmd_bootm.c Image is for unsupported architecture 3019 5 common/cmd_bootm.c Architecture check OK 3020 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 3021 6 common/cmd_bootm.c Image Type check OK 3022 -6 common/cmd_bootm.c gunzip uncompression error 3023 -7 common/cmd_bootm.c Unimplemented compression type 3024 7 common/cmd_bootm.c Uncompression OK 3025 8 common/cmd_bootm.c No uncompress/copy overwrite error 3026 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 3027 3028 9 common/image.c Start initial ramdisk verification 3029 -10 common/image.c Ramdisk header has bad magic number 3030 -11 common/image.c Ramdisk header has bad checksum 3031 10 common/image.c Ramdisk header is OK 3032 -12 common/image.c Ramdisk data has bad checksum 3033 11 common/image.c Ramdisk data has correct checksum 3034 12 common/image.c Ramdisk verification complete, start loading 3035 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 3036 13 common/image.c Start multifile image verification 3037 14 common/image.c No initial ramdisk, no multifile, continue. 3038 3039 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 3040 3041 -30 arch/powerpc/lib/board.c Fatal error, hang the system 3042 -31 post/post.c POST test failed, detected by post_output_backlog() 3043 -32 post/post.c POST test failed, detected by post_run_single() 3044 3045 34 common/cmd_doc.c before loading a Image from a DOC device 3046 -35 common/cmd_doc.c Bad usage of "doc" command 3047 35 common/cmd_doc.c correct usage of "doc" command 3048 -36 common/cmd_doc.c No boot device 3049 36 common/cmd_doc.c correct boot device 3050 -37 common/cmd_doc.c Unknown Chip ID on boot device 3051 37 common/cmd_doc.c correct chip ID found, device available 3052 -38 common/cmd_doc.c Read Error on boot device 3053 38 common/cmd_doc.c reading Image header from DOC device OK 3054 -39 common/cmd_doc.c Image header has bad magic number 3055 39 common/cmd_doc.c Image header has correct magic number 3056 -40 common/cmd_doc.c Error reading Image from DOC device 3057 40 common/cmd_doc.c Image header has correct magic number 3058 41 common/cmd_ide.c before loading a Image from a IDE device 3059 -42 common/cmd_ide.c Bad usage of "ide" command 3060 42 common/cmd_ide.c correct usage of "ide" command 3061 -43 common/cmd_ide.c No boot device 3062 43 common/cmd_ide.c boot device found 3063 -44 common/cmd_ide.c Device not available 3064 44 common/cmd_ide.c Device available 3065 -45 common/cmd_ide.c wrong partition selected 3066 45 common/cmd_ide.c partition selected 3067 -46 common/cmd_ide.c Unknown partition table 3068 46 common/cmd_ide.c valid partition table found 3069 -47 common/cmd_ide.c Invalid partition type 3070 47 common/cmd_ide.c correct partition type 3071 -48 common/cmd_ide.c Error reading Image Header on boot device 3072 48 common/cmd_ide.c reading Image Header from IDE device OK 3073 -49 common/cmd_ide.c Image header has bad magic number 3074 49 common/cmd_ide.c Image header has correct magic number 3075 -50 common/cmd_ide.c Image header has bad checksum 3076 50 common/cmd_ide.c Image header has correct checksum 3077 -51 common/cmd_ide.c Error reading Image from IDE device 3078 51 common/cmd_ide.c reading Image from IDE device OK 3079 52 common/cmd_nand.c before loading a Image from a NAND device 3080 -53 common/cmd_nand.c Bad usage of "nand" command 3081 53 common/cmd_nand.c correct usage of "nand" command 3082 -54 common/cmd_nand.c No boot device 3083 54 common/cmd_nand.c boot device found 3084 -55 common/cmd_nand.c Unknown Chip ID on boot device 3085 55 common/cmd_nand.c correct chip ID found, device available 3086 -56 common/cmd_nand.c Error reading Image Header on boot device 3087 56 common/cmd_nand.c reading Image Header from NAND device OK 3088 -57 common/cmd_nand.c Image header has bad magic number 3089 57 common/cmd_nand.c Image header has correct magic number 3090 -58 common/cmd_nand.c Error reading Image from NAND device 3091 58 common/cmd_nand.c reading Image from NAND device OK 3092 3093 -60 common/env_common.c Environment has a bad CRC, using default 3094 3095 64 net/eth.c starting with Ethernet configuration. 3096 -64 net/eth.c no Ethernet found. 3097 65 net/eth.c Ethernet found. 3098 3099 -80 common/cmd_net.c usage wrong 3100 80 common/cmd_net.c before calling NetLoop() 3101 -81 common/cmd_net.c some error in NetLoop() occurred 3102 81 common/cmd_net.c NetLoop() back without error 3103 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 3104 82 common/cmd_net.c trying automatic boot 3105 83 common/cmd_net.c running "source" command 3106 -83 common/cmd_net.c some error in automatic boot or "source" command 3107 84 common/cmd_net.c end without errors 3108 3109FIT uImage format: 3110 3111 Arg Where When 3112 100 common/cmd_bootm.c Kernel FIT Image has correct format 3113 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 3114 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 3115 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 3116 102 common/cmd_bootm.c Kernel unit name specified 3117 -103 common/cmd_bootm.c Can't get kernel subimage node offset 3118 103 common/cmd_bootm.c Found configuration node 3119 104 common/cmd_bootm.c Got kernel subimage node offset 3120 -104 common/cmd_bootm.c Kernel subimage hash verification failed 3121 105 common/cmd_bootm.c Kernel subimage hash verification OK 3122 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 3123 106 common/cmd_bootm.c Architecture check OK 3124 -106 common/cmd_bootm.c Kernel subimage has wrong type 3125 107 common/cmd_bootm.c Kernel subimage type OK 3126 -107 common/cmd_bootm.c Can't get kernel subimage data/size 3127 108 common/cmd_bootm.c Got kernel subimage data/size 3128 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 3129 -109 common/cmd_bootm.c Can't get kernel subimage type 3130 -110 common/cmd_bootm.c Can't get kernel subimage comp 3131 -111 common/cmd_bootm.c Can't get kernel subimage os 3132 -112 common/cmd_bootm.c Can't get kernel subimage load address 3133 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 3134 3135 120 common/image.c Start initial ramdisk verification 3136 -120 common/image.c Ramdisk FIT image has incorrect format 3137 121 common/image.c Ramdisk FIT image has correct format 3138 122 common/image.c No ramdisk subimage unit name, using configuration 3139 -122 common/image.c Can't get configuration for ramdisk subimage 3140 123 common/image.c Ramdisk unit name specified 3141 -124 common/image.c Can't get ramdisk subimage node offset 3142 125 common/image.c Got ramdisk subimage node offset 3143 -125 common/image.c Ramdisk subimage hash verification failed 3144 126 common/image.c Ramdisk subimage hash verification OK 3145 -126 common/image.c Ramdisk subimage for unsupported architecture 3146 127 common/image.c Architecture check OK 3147 -127 common/image.c Can't get ramdisk subimage data/size 3148 128 common/image.c Got ramdisk subimage data/size 3149 129 common/image.c Can't get ramdisk load address 3150 -129 common/image.c Got ramdisk load address 3151 3152 -130 common/cmd_doc.c Incorrect FIT image format 3153 131 common/cmd_doc.c FIT image format OK 3154 3155 -140 common/cmd_ide.c Incorrect FIT image format 3156 141 common/cmd_ide.c FIT image format OK 3157 3158 -150 common/cmd_nand.c Incorrect FIT image format 3159 151 common/cmd_nand.c FIT image format OK 3160 3161- FIT image support: 3162 CONFIG_FIT 3163 Enable support for the FIT uImage format. 3164 3165 CONFIG_FIT_BEST_MATCH 3166 When no configuration is explicitly selected, default to the 3167 one whose fdt's compatibility field best matches that of 3168 U-Boot itself. A match is considered "best" if it matches the 3169 most specific compatibility entry of U-Boot's fdt's root node. 3170 The order of entries in the configuration's fdt is ignored. 3171 3172 CONFIG_FIT_SIGNATURE 3173 This option enables signature verification of FIT uImages, 3174 using a hash signed and verified using RSA. See 3175 doc/uImage.FIT/signature.txt for more details. 3176 3177- Standalone program support: 3178 CONFIG_STANDALONE_LOAD_ADDR 3179 3180 This option defines a board specific value for the 3181 address where standalone program gets loaded, thus 3182 overwriting the architecture dependent default 3183 settings. 3184 3185- Frame Buffer Address: 3186 CONFIG_FB_ADDR 3187 3188 Define CONFIG_FB_ADDR if you want to use specific 3189 address for frame buffer. This is typically the case 3190 when using a graphics controller has separate video 3191 memory. U-Boot will then place the frame buffer at 3192 the given address instead of dynamically reserving it 3193 in system RAM by calling lcd_setmem(), which grabs 3194 the memory for the frame buffer depending on the 3195 configured panel size. 3196 3197 Please see board_init_f function. 3198 3199- Automatic software updates via TFTP server 3200 CONFIG_UPDATE_TFTP 3201 CONFIG_UPDATE_TFTP_CNT_MAX 3202 CONFIG_UPDATE_TFTP_MSEC_MAX 3203 3204 These options enable and control the auto-update feature; 3205 for a more detailed description refer to doc/README.update. 3206 3207- MTD Support (mtdparts command, UBI support) 3208 CONFIG_MTD_DEVICE 3209 3210 Adds the MTD device infrastructure from the Linux kernel. 3211 Needed for mtdparts command support. 3212 3213 CONFIG_MTD_PARTITIONS 3214 3215 Adds the MTD partitioning infrastructure from the Linux 3216 kernel. Needed for UBI support. 3217 3218- UBI support 3219 CONFIG_CMD_UBI 3220 3221 Adds commands for interacting with MTD partitions formatted 3222 with the UBI flash translation layer 3223 3224 Requires also defining CONFIG_RBTREE 3225 3226 CONFIG_UBI_SILENCE_MSG 3227 3228 Make the verbose messages from UBI stop printing. This leaves 3229 warnings and errors enabled. 3230 3231- UBIFS support 3232 CONFIG_CMD_UBIFS 3233 3234 Adds commands for interacting with UBI volumes formatted as 3235 UBIFS. UBIFS is read-only in u-boot. 3236 3237 Requires UBI support as well as CONFIG_LZO 3238 3239 CONFIG_UBIFS_SILENCE_MSG 3240 3241 Make the verbose messages from UBIFS stop printing. This leaves 3242 warnings and errors enabled. 3243 3244- SPL framework 3245 CONFIG_SPL 3246 Enable building of SPL globally. 3247 3248 CONFIG_SPL_LDSCRIPT 3249 LDSCRIPT for linking the SPL binary. 3250 3251 CONFIG_SPL_MAX_FOOTPRINT 3252 Maximum size in memory allocated to the SPL, BSS included. 3253 When defined, the linker checks that the actual memory 3254 used by SPL from _start to __bss_end does not exceed it. 3255 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3256 must not be both defined at the same time. 3257 3258 CONFIG_SPL_MAX_SIZE 3259 Maximum size of the SPL image (text, data, rodata, and 3260 linker lists sections), BSS excluded. 3261 When defined, the linker checks that the actual size does 3262 not exceed it. 3263 3264 CONFIG_SPL_TEXT_BASE 3265 TEXT_BASE for linking the SPL binary. 3266 3267 CONFIG_SPL_RELOC_TEXT_BASE 3268 Address to relocate to. If unspecified, this is equal to 3269 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3270 3271 CONFIG_SPL_BSS_START_ADDR 3272 Link address for the BSS within the SPL binary. 3273 3274 CONFIG_SPL_BSS_MAX_SIZE 3275 Maximum size in memory allocated to the SPL BSS. 3276 When defined, the linker checks that the actual memory used 3277 by SPL from __bss_start to __bss_end does not exceed it. 3278 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3279 must not be both defined at the same time. 3280 3281 CONFIG_SPL_STACK 3282 Adress of the start of the stack SPL will use 3283 3284 CONFIG_SPL_RELOC_STACK 3285 Adress of the start of the stack SPL will use after 3286 relocation. If unspecified, this is equal to 3287 CONFIG_SPL_STACK. 3288 3289 CONFIG_SYS_SPL_MALLOC_START 3290 Starting address of the malloc pool used in SPL. 3291 3292 CONFIG_SYS_SPL_MALLOC_SIZE 3293 The size of the malloc pool used in SPL. 3294 3295 CONFIG_SPL_FRAMEWORK 3296 Enable the SPL framework under common/. This framework 3297 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3298 NAND loading of the Linux Kernel. 3299 3300 CONFIG_SPL_DISPLAY_PRINT 3301 For ARM, enable an optional function to print more information 3302 about the running system. 3303 3304 CONFIG_SPL_INIT_MINIMAL 3305 Arch init code should be built for a very small image 3306 3307 CONFIG_SPL_LIBCOMMON_SUPPORT 3308 Support for common/libcommon.o in SPL binary 3309 3310 CONFIG_SPL_LIBDISK_SUPPORT 3311 Support for disk/libdisk.o in SPL binary 3312 3313 CONFIG_SPL_I2C_SUPPORT 3314 Support for drivers/i2c/libi2c.o in SPL binary 3315 3316 CONFIG_SPL_GPIO_SUPPORT 3317 Support for drivers/gpio/libgpio.o in SPL binary 3318 3319 CONFIG_SPL_MMC_SUPPORT 3320 Support for drivers/mmc/libmmc.o in SPL binary 3321 3322 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 3323 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 3324 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION 3325 Address, size and partition on the MMC to load U-Boot from 3326 when the MMC is being used in raw mode. 3327 3328 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3329 Sector to load kernel uImage from when MMC is being 3330 used in raw mode (for Falcon mode) 3331 3332 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3333 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3334 Sector and number of sectors to load kernel argument 3335 parameters from when MMC is being used in raw mode 3336 (for falcon mode) 3337 3338 CONFIG_SPL_FAT_SUPPORT 3339 Support for fs/fat/libfat.o in SPL binary 3340 3341 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME 3342 Filename to read to load U-Boot when reading from FAT 3343 3344 CONFIG_SPL_FAT_LOAD_KERNEL_NAME 3345 Filename to read to load kernel uImage when reading 3346 from FAT (for Falcon mode) 3347 3348 CONFIG_SPL_FAT_LOAD_ARGS_NAME 3349 Filename to read to load kernel argument parameters 3350 when reading from FAT (for Falcon mode) 3351 3352 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3353 Set this for NAND SPL on PPC mpc83xx targets, so that 3354 start.S waits for the rest of the SPL to load before 3355 continuing (the hardware starts execution after just 3356 loading the first page rather than the full 4K). 3357 3358 CONFIG_SPL_SKIP_RELOCATE 3359 Avoid SPL relocation 3360 3361 CONFIG_SPL_NAND_BASE 3362 Include nand_base.c in the SPL. Requires 3363 CONFIG_SPL_NAND_DRIVERS. 3364 3365 CONFIG_SPL_NAND_DRIVERS 3366 SPL uses normal NAND drivers, not minimal drivers. 3367 3368 CONFIG_SPL_NAND_ECC 3369 Include standard software ECC in the SPL 3370 3371 CONFIG_SPL_NAND_SIMPLE 3372 Support for NAND boot using simple NAND drivers that 3373 expose the cmd_ctrl() interface. 3374 3375 CONFIG_SPL_MPC8XXX_INIT_DDR_SUPPORT 3376 Set for the SPL on PPC mpc8xxx targets, support for 3377 drivers/ddr/fsl/libddr.o in SPL binary. 3378 3379 CONFIG_SPL_COMMON_INIT_DDR 3380 Set for common ddr init with serial presence detect in 3381 SPL binary. 3382 3383 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3384 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3385 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3386 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3387 CONFIG_SYS_NAND_ECCBYTES 3388 Defines the size and behavior of the NAND that SPL uses 3389 to read U-Boot 3390 3391 CONFIG_SPL_NAND_BOOT 3392 Add support NAND boot 3393 3394 CONFIG_SYS_NAND_U_BOOT_OFFS 3395 Location in NAND to read U-Boot from 3396 3397 CONFIG_SYS_NAND_U_BOOT_DST 3398 Location in memory to load U-Boot to 3399 3400 CONFIG_SYS_NAND_U_BOOT_SIZE 3401 Size of image to load 3402 3403 CONFIG_SYS_NAND_U_BOOT_START 3404 Entry point in loaded image to jump to 3405 3406 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3407 Define this if you need to first read the OOB and then the 3408 data. This is used for example on davinci plattforms. 3409 3410 CONFIG_SPL_OMAP3_ID_NAND 3411 Support for an OMAP3-specific set of functions to return the 3412 ID and MFR of the first attached NAND chip, if present. 3413 3414 CONFIG_SPL_SERIAL_SUPPORT 3415 Support for drivers/serial/libserial.o in SPL binary 3416 3417 CONFIG_SPL_SPI_FLASH_SUPPORT 3418 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 3419 3420 CONFIG_SPL_SPI_SUPPORT 3421 Support for drivers/spi/libspi.o in SPL binary 3422 3423 CONFIG_SPL_RAM_DEVICE 3424 Support for running image already present in ram, in SPL binary 3425 3426 CONFIG_SPL_LIBGENERIC_SUPPORT 3427 Support for lib/libgeneric.o in SPL binary 3428 3429 CONFIG_SPL_ENV_SUPPORT 3430 Support for the environment operating in SPL binary 3431 3432 CONFIG_SPL_NET_SUPPORT 3433 Support for the net/libnet.o in SPL binary. 3434 It conflicts with SPL env from storage medium specified by 3435 CONFIG_ENV_IS_xxx but CONFIG_ENV_IS_NOWHERE 3436 3437 CONFIG_SPL_PAD_TO 3438 Image offset to which the SPL should be padded before appending 3439 the SPL payload. By default, this is defined as 3440 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3441 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3442 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3443 3444 CONFIG_SPL_TARGET 3445 Final target image containing SPL and payload. Some SPLs 3446 use an arch-specific makefile fragment instead, for 3447 example if more than one image needs to be produced. 3448 3449 CONFIG_FIT_SPL_PRINT 3450 Printing information about a FIT image adds quite a bit of 3451 code to SPL. So this is normally disabled in SPL. Use this 3452 option to re-enable it. This will affect the output of the 3453 bootm command when booting a FIT image. 3454 3455- TPL framework 3456 CONFIG_TPL 3457 Enable building of TPL globally. 3458 3459 CONFIG_TPL_PAD_TO 3460 Image offset to which the TPL should be padded before appending 3461 the TPL payload. By default, this is defined as 3462 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3463 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3464 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3465 3466Modem Support: 3467-------------- 3468 3469[so far only for SMDK2400 boards] 3470 3471- Modem support enable: 3472 CONFIG_MODEM_SUPPORT 3473 3474- RTS/CTS Flow control enable: 3475 CONFIG_HWFLOW 3476 3477- Modem debug support: 3478 CONFIG_MODEM_SUPPORT_DEBUG 3479 3480 Enables debugging stuff (char screen[1024], dbg()) 3481 for modem support. Useful only with BDI2000. 3482 3483- Interrupt support (PPC): 3484 3485 There are common interrupt_init() and timer_interrupt() 3486 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3487 for CPU specific initialization. interrupt_init_cpu() 3488 should set decrementer_count to appropriate value. If 3489 CPU resets decrementer automatically after interrupt 3490 (ppc4xx) it should set decrementer_count to zero. 3491 timer_interrupt() calls timer_interrupt_cpu() for CPU 3492 specific handling. If board has watchdog / status_led 3493 / other_activity_monitor it works automatically from 3494 general timer_interrupt(). 3495 3496- General: 3497 3498 In the target system modem support is enabled when a 3499 specific key (key combination) is pressed during 3500 power-on. Otherwise U-Boot will boot normally 3501 (autoboot). The key_pressed() function is called from 3502 board_init(). Currently key_pressed() is a dummy 3503 function, returning 1 and thus enabling modem 3504 initialization. 3505 3506 If there are no modem init strings in the 3507 environment, U-Boot proceed to autoboot; the 3508 previous output (banner, info printfs) will be 3509 suppressed, though. 3510 3511 See also: doc/README.Modem 3512 3513Board initialization settings: 3514------------------------------ 3515 3516During Initialization u-boot calls a number of board specific functions 3517to allow the preparation of board specific prerequisites, e.g. pin setup 3518before drivers are initialized. To enable these callbacks the 3519following configuration macros have to be defined. Currently this is 3520architecture specific, so please check arch/your_architecture/lib/board.c 3521typically in board_init_f() and board_init_r(). 3522 3523- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3524- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3525- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3526- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3527 3528Configuration Settings: 3529----------------------- 3530 3531- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3532 Optionally it can be defined to support 64-bit memory commands. 3533 3534- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3535 undefine this when you're short of memory. 3536 3537- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3538 width of the commands listed in the 'help' command output. 3539 3540- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3541 prompt for user input. 3542 3543- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3544 3545- CONFIG_SYS_PBSIZE: Buffer size for Console output 3546 3547- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3548 3549- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3550 the application (usually a Linux kernel) when it is 3551 booted 3552 3553- CONFIG_SYS_BAUDRATE_TABLE: 3554 List of legal baudrate settings for this board. 3555 3556- CONFIG_SYS_CONSOLE_INFO_QUIET 3557 Suppress display of console information at boot. 3558 3559- CONFIG_SYS_CONSOLE_IS_IN_ENV 3560 If the board specific function 3561 extern int overwrite_console (void); 3562 returns 1, the stdin, stderr and stdout are switched to the 3563 serial port, else the settings in the environment are used. 3564 3565- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3566 Enable the call to overwrite_console(). 3567 3568- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3569 Enable overwrite of previous console environment settings. 3570 3571- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3572 Begin and End addresses of the area used by the 3573 simple memory test. 3574 3575- CONFIG_SYS_ALT_MEMTEST: 3576 Enable an alternate, more extensive memory test. 3577 3578- CONFIG_SYS_MEMTEST_SCRATCH: 3579 Scratch address used by the alternate memory test 3580 You only need to set this if address zero isn't writeable 3581 3582- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3583 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3584 this specified memory area will get subtracted from the top 3585 (end) of RAM and won't get "touched" at all by U-Boot. By 3586 fixing up gd->ram_size the Linux kernel should gets passed 3587 the now "corrected" memory size and won't touch it either. 3588 This should work for arch/ppc and arch/powerpc. Only Linux 3589 board ports in arch/powerpc with bootwrapper support that 3590 recalculate the memory size from the SDRAM controller setup 3591 will have to get fixed in Linux additionally. 3592 3593 This option can be used as a workaround for the 440EPx/GRx 3594 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3595 be touched. 3596 3597 WARNING: Please make sure that this value is a multiple of 3598 the Linux page size (normally 4k). If this is not the case, 3599 then the end address of the Linux memory will be located at a 3600 non page size aligned address and this could cause major 3601 problems. 3602 3603- CONFIG_SYS_LOADS_BAUD_CHANGE: 3604 Enable temporary baudrate change while serial download 3605 3606- CONFIG_SYS_SDRAM_BASE: 3607 Physical start address of SDRAM. _Must_ be 0 here. 3608 3609- CONFIG_SYS_MBIO_BASE: 3610 Physical start address of Motherboard I/O (if using a 3611 Cogent motherboard) 3612 3613- CONFIG_SYS_FLASH_BASE: 3614 Physical start address of Flash memory. 3615 3616- CONFIG_SYS_MONITOR_BASE: 3617 Physical start address of boot monitor code (set by 3618 make config files to be same as the text base address 3619 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3620 CONFIG_SYS_FLASH_BASE when booting from flash. 3621 3622- CONFIG_SYS_MONITOR_LEN: 3623 Size of memory reserved for monitor code, used to 3624 determine _at_compile_time_ (!) if the environment is 3625 embedded within the U-Boot image, or in a separate 3626 flash sector. 3627 3628- CONFIG_SYS_MALLOC_LEN: 3629 Size of DRAM reserved for malloc() use. 3630 3631- CONFIG_SYS_BOOTM_LEN: 3632 Normally compressed uImages are limited to an 3633 uncompressed size of 8 MBytes. If this is not enough, 3634 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3635 to adjust this setting to your needs. 3636 3637- CONFIG_SYS_BOOTMAPSZ: 3638 Maximum size of memory mapped by the startup code of 3639 the Linux kernel; all data that must be processed by 3640 the Linux kernel (bd_info, boot arguments, FDT blob if 3641 used) must be put below this limit, unless "bootm_low" 3642 environment variable is defined and non-zero. In such case 3643 all data for the Linux kernel must be between "bootm_low" 3644 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3645 variable "bootm_mapsize" will override the value of 3646 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3647 then the value in "bootm_size" will be used instead. 3648 3649- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3650 Enable initrd_high functionality. If defined then the 3651 initrd_high feature is enabled and the bootm ramdisk subcommand 3652 is enabled. 3653 3654- CONFIG_SYS_BOOT_GET_CMDLINE: 3655 Enables allocating and saving kernel cmdline in space between 3656 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3657 3658- CONFIG_SYS_BOOT_GET_KBD: 3659 Enables allocating and saving a kernel copy of the bd_info in 3660 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3661 3662- CONFIG_SYS_MAX_FLASH_BANKS: 3663 Max number of Flash memory banks 3664 3665- CONFIG_SYS_MAX_FLASH_SECT: 3666 Max number of sectors on a Flash chip 3667 3668- CONFIG_SYS_FLASH_ERASE_TOUT: 3669 Timeout for Flash erase operations (in ms) 3670 3671- CONFIG_SYS_FLASH_WRITE_TOUT: 3672 Timeout for Flash write operations (in ms) 3673 3674- CONFIG_SYS_FLASH_LOCK_TOUT 3675 Timeout for Flash set sector lock bit operation (in ms) 3676 3677- CONFIG_SYS_FLASH_UNLOCK_TOUT 3678 Timeout for Flash clear lock bits operation (in ms) 3679 3680- CONFIG_SYS_FLASH_PROTECTION 3681 If defined, hardware flash sectors protection is used 3682 instead of U-Boot software protection. 3683 3684- CONFIG_SYS_DIRECT_FLASH_TFTP: 3685 3686 Enable TFTP transfers directly to flash memory; 3687 without this option such a download has to be 3688 performed in two steps: (1) download to RAM, and (2) 3689 copy from RAM to flash. 3690 3691 The two-step approach is usually more reliable, since 3692 you can check if the download worked before you erase 3693 the flash, but in some situations (when system RAM is 3694 too limited to allow for a temporary copy of the 3695 downloaded image) this option may be very useful. 3696 3697- CONFIG_SYS_FLASH_CFI: 3698 Define if the flash driver uses extra elements in the 3699 common flash structure for storing flash geometry. 3700 3701- CONFIG_FLASH_CFI_DRIVER 3702 This option also enables the building of the cfi_flash driver 3703 in the drivers directory 3704 3705- CONFIG_FLASH_CFI_MTD 3706 This option enables the building of the cfi_mtd driver 3707 in the drivers directory. The driver exports CFI flash 3708 to the MTD layer. 3709 3710- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3711 Use buffered writes to flash. 3712 3713- CONFIG_FLASH_SPANSION_S29WS_N 3714 s29ws-n MirrorBit flash has non-standard addresses for buffered 3715 write commands. 3716 3717- CONFIG_SYS_FLASH_QUIET_TEST 3718 If this option is defined, the common CFI flash doesn't 3719 print it's warning upon not recognized FLASH banks. This 3720 is useful, if some of the configured banks are only 3721 optionally available. 3722 3723- CONFIG_FLASH_SHOW_PROGRESS 3724 If defined (must be an integer), print out countdown 3725 digits and dots. Recommended value: 45 (9..1) for 80 3726 column displays, 15 (3..1) for 40 column displays. 3727 3728- CONFIG_FLASH_VERIFY 3729 If defined, the content of the flash (destination) is compared 3730 against the source after the write operation. An error message 3731 will be printed when the contents are not identical. 3732 Please note that this option is useless in nearly all cases, 3733 since such flash programming errors usually are detected earlier 3734 while unprotecting/erasing/programming. Please only enable 3735 this option if you really know what you are doing. 3736 3737- CONFIG_SYS_RX_ETH_BUFFER: 3738 Defines the number of Ethernet receive buffers. On some 3739 Ethernet controllers it is recommended to set this value 3740 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3741 buffers can be full shortly after enabling the interface 3742 on high Ethernet traffic. 3743 Defaults to 4 if not defined. 3744 3745- CONFIG_ENV_MAX_ENTRIES 3746 3747 Maximum number of entries in the hash table that is used 3748 internally to store the environment settings. The default 3749 setting is supposed to be generous and should work in most 3750 cases. This setting can be used to tune behaviour; see 3751 lib/hashtable.c for details. 3752 3753- CONFIG_ENV_FLAGS_LIST_DEFAULT 3754- CONFIG_ENV_FLAGS_LIST_STATIC 3755 Enable validation of the values given to environment variables when 3756 calling env set. Variables can be restricted to only decimal, 3757 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3758 the variables can also be restricted to IP address or MAC address. 3759 3760 The format of the list is: 3761 type_attribute = [s|d|x|b|i|m] 3762 access_atribute = [a|r|o|c] 3763 attributes = type_attribute[access_atribute] 3764 entry = variable_name[:attributes] 3765 list = entry[,list] 3766 3767 The type attributes are: 3768 s - String (default) 3769 d - Decimal 3770 x - Hexadecimal 3771 b - Boolean ([1yYtT|0nNfF]) 3772 i - IP address 3773 m - MAC address 3774 3775 The access attributes are: 3776 a - Any (default) 3777 r - Read-only 3778 o - Write-once 3779 c - Change-default 3780 3781 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3782 Define this to a list (string) to define the ".flags" 3783 envirnoment variable in the default or embedded environment. 3784 3785 - CONFIG_ENV_FLAGS_LIST_STATIC 3786 Define this to a list (string) to define validation that 3787 should be done if an entry is not found in the ".flags" 3788 environment variable. To override a setting in the static 3789 list, simply add an entry for the same variable name to the 3790 ".flags" variable. 3791 3792- CONFIG_ENV_ACCESS_IGNORE_FORCE 3793 If defined, don't allow the -f switch to env set override variable 3794 access flags. 3795 3796- CONFIG_SYS_GENERIC_BOARD 3797 This selects the architecture-generic board system instead of the 3798 architecture-specific board files. It is intended to move boards 3799 to this new framework over time. Defining this will disable the 3800 arch/foo/lib/board.c file and use common/board_f.c and 3801 common/board_r.c instead. To use this option your architecture 3802 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in 3803 its config.mk file). If you find problems enabling this option on 3804 your board please report the problem and send patches! 3805 3806- CONFIG_OMAP_PLATFORM_RESET_TIME_MAX_USEC (OMAP only) 3807 This is set by OMAP boards for the max time that reset should 3808 be asserted. See doc/README.omap-reset-time for details on how 3809 the value can be calulated on a given board. 3810 3811The following definitions that deal with the placement and management 3812of environment data (variable area); in general, we support the 3813following configurations: 3814 3815- CONFIG_BUILD_ENVCRC: 3816 3817 Builds up envcrc with the target environment so that external utils 3818 may easily extract it and embed it in final U-Boot images. 3819 3820- CONFIG_ENV_IS_IN_FLASH: 3821 3822 Define this if the environment is in flash memory. 3823 3824 a) The environment occupies one whole flash sector, which is 3825 "embedded" in the text segment with the U-Boot code. This 3826 happens usually with "bottom boot sector" or "top boot 3827 sector" type flash chips, which have several smaller 3828 sectors at the start or the end. For instance, such a 3829 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3830 such a case you would place the environment in one of the 3831 4 kB sectors - with U-Boot code before and after it. With 3832 "top boot sector" type flash chips, you would put the 3833 environment in one of the last sectors, leaving a gap 3834 between U-Boot and the environment. 3835 3836 - CONFIG_ENV_OFFSET: 3837 3838 Offset of environment data (variable area) to the 3839 beginning of flash memory; for instance, with bottom boot 3840 type flash chips the second sector can be used: the offset 3841 for this sector is given here. 3842 3843 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3844 3845 - CONFIG_ENV_ADDR: 3846 3847 This is just another way to specify the start address of 3848 the flash sector containing the environment (instead of 3849 CONFIG_ENV_OFFSET). 3850 3851 - CONFIG_ENV_SECT_SIZE: 3852 3853 Size of the sector containing the environment. 3854 3855 3856 b) Sometimes flash chips have few, equal sized, BIG sectors. 3857 In such a case you don't want to spend a whole sector for 3858 the environment. 3859 3860 - CONFIG_ENV_SIZE: 3861 3862 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3863 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3864 of this flash sector for the environment. This saves 3865 memory for the RAM copy of the environment. 3866 3867 It may also save flash memory if you decide to use this 3868 when your environment is "embedded" within U-Boot code, 3869 since then the remainder of the flash sector could be used 3870 for U-Boot code. It should be pointed out that this is 3871 STRONGLY DISCOURAGED from a robustness point of view: 3872 updating the environment in flash makes it always 3873 necessary to erase the WHOLE sector. If something goes 3874 wrong before the contents has been restored from a copy in 3875 RAM, your target system will be dead. 3876 3877 - CONFIG_ENV_ADDR_REDUND 3878 CONFIG_ENV_SIZE_REDUND 3879 3880 These settings describe a second storage area used to hold 3881 a redundant copy of the environment data, so that there is 3882 a valid backup copy in case there is a power failure during 3883 a "saveenv" operation. 3884 3885BE CAREFUL! Any changes to the flash layout, and some changes to the 3886source code will make it necessary to adapt <board>/u-boot.lds* 3887accordingly! 3888 3889 3890- CONFIG_ENV_IS_IN_NVRAM: 3891 3892 Define this if you have some non-volatile memory device 3893 (NVRAM, battery buffered SRAM) which you want to use for the 3894 environment. 3895 3896 - CONFIG_ENV_ADDR: 3897 - CONFIG_ENV_SIZE: 3898 3899 These two #defines are used to determine the memory area you 3900 want to use for environment. It is assumed that this memory 3901 can just be read and written to, without any special 3902 provision. 3903 3904BE CAREFUL! The first access to the environment happens quite early 3905in U-Boot initalization (when we try to get the setting of for the 3906console baudrate). You *MUST* have mapped your NVRAM area then, or 3907U-Boot will hang. 3908 3909Please note that even with NVRAM we still use a copy of the 3910environment in RAM: we could work on NVRAM directly, but we want to 3911keep settings there always unmodified except somebody uses "saveenv" 3912to save the current settings. 3913 3914 3915- CONFIG_ENV_IS_IN_EEPROM: 3916 3917 Use this if you have an EEPROM or similar serial access 3918 device and a driver for it. 3919 3920 - CONFIG_ENV_OFFSET: 3921 - CONFIG_ENV_SIZE: 3922 3923 These two #defines specify the offset and size of the 3924 environment area within the total memory of your EEPROM. 3925 3926 - CONFIG_SYS_I2C_EEPROM_ADDR: 3927 If defined, specified the chip address of the EEPROM device. 3928 The default address is zero. 3929 3930 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3931 If defined, the number of bits used to address bytes in a 3932 single page in the EEPROM device. A 64 byte page, for example 3933 would require six bits. 3934 3935 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3936 If defined, the number of milliseconds to delay between 3937 page writes. The default is zero milliseconds. 3938 3939 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3940 The length in bytes of the EEPROM memory array address. Note 3941 that this is NOT the chip address length! 3942 3943 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3944 EEPROM chips that implement "address overflow" are ones 3945 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3946 address and the extra bits end up in the "chip address" bit 3947 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3948 byte chips. 3949 3950 Note that we consider the length of the address field to 3951 still be one byte because the extra address bits are hidden 3952 in the chip address. 3953 3954 - CONFIG_SYS_EEPROM_SIZE: 3955 The size in bytes of the EEPROM device. 3956 3957 - CONFIG_ENV_EEPROM_IS_ON_I2C 3958 define this, if you have I2C and SPI activated, and your 3959 EEPROM, which holds the environment, is on the I2C bus. 3960 3961 - CONFIG_I2C_ENV_EEPROM_BUS 3962 if you have an Environment on an EEPROM reached over 3963 I2C muxes, you can define here, how to reach this 3964 EEPROM. For example: 3965 3966 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3967 3968 EEPROM which holds the environment, is reached over 3969 a pca9547 i2c mux with address 0x70, channel 3. 3970 3971- CONFIG_ENV_IS_IN_DATAFLASH: 3972 3973 Define this if you have a DataFlash memory device which you 3974 want to use for the environment. 3975 3976 - CONFIG_ENV_OFFSET: 3977 - CONFIG_ENV_ADDR: 3978 - CONFIG_ENV_SIZE: 3979 3980 These three #defines specify the offset and size of the 3981 environment area within the total memory of your DataFlash placed 3982 at the specified address. 3983 3984- CONFIG_ENV_IS_IN_REMOTE: 3985 3986 Define this if you have a remote memory space which you 3987 want to use for the local device's environment. 3988 3989 - CONFIG_ENV_ADDR: 3990 - CONFIG_ENV_SIZE: 3991 3992 These two #defines specify the address and size of the 3993 environment area within the remote memory space. The 3994 local device can get the environment from remote memory 3995 space by SRIO or PCIE links. 3996 3997BE CAREFUL! For some special cases, the local device can not use 3998"saveenv" command. For example, the local device will get the 3999environment stored in a remote NOR flash by SRIO or PCIE link, 4000but it can not erase, write this NOR flash by SRIO or PCIE interface. 4001 4002- CONFIG_ENV_IS_IN_NAND: 4003 4004 Define this if you have a NAND device which you want to use 4005 for the environment. 4006 4007 - CONFIG_ENV_OFFSET: 4008 - CONFIG_ENV_SIZE: 4009 4010 These two #defines specify the offset and size of the environment 4011 area within the first NAND device. CONFIG_ENV_OFFSET must be 4012 aligned to an erase block boundary. 4013 4014 - CONFIG_ENV_OFFSET_REDUND (optional): 4015 4016 This setting describes a second storage area of CONFIG_ENV_SIZE 4017 size used to hold a redundant copy of the environment data, so 4018 that there is a valid backup copy in case there is a power failure 4019 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 4020 aligned to an erase block boundary. 4021 4022 - CONFIG_ENV_RANGE (optional): 4023 4024 Specifies the length of the region in which the environment 4025 can be written. This should be a multiple of the NAND device's 4026 block size. Specifying a range with more erase blocks than 4027 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 4028 the range to be avoided. 4029 4030 - CONFIG_ENV_OFFSET_OOB (optional): 4031 4032 Enables support for dynamically retrieving the offset of the 4033 environment from block zero's out-of-band data. The 4034 "nand env.oob" command can be used to record this offset. 4035 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 4036 using CONFIG_ENV_OFFSET_OOB. 4037 4038- CONFIG_NAND_ENV_DST 4039 4040 Defines address in RAM to which the nand_spl code should copy the 4041 environment. If redundant environment is used, it will be copied to 4042 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 4043 4044- CONFIG_ENV_IS_IN_UBI: 4045 4046 Define this if you have an UBI volume that you want to use for the 4047 environment. This has the benefit of wear-leveling the environment 4048 accesses, which is important on NAND. 4049 4050 - CONFIG_ENV_UBI_PART: 4051 4052 Define this to a string that is the mtd partition containing the UBI. 4053 4054 - CONFIG_ENV_UBI_VOLUME: 4055 4056 Define this to the name of the volume that you want to store the 4057 environment in. 4058 4059 - CONFIG_ENV_UBI_VOLUME_REDUND: 4060 4061 Define this to the name of another volume to store a second copy of 4062 the environment in. This will enable redundant environments in UBI. 4063 It is assumed that both volumes are in the same MTD partition. 4064 4065 - CONFIG_UBI_SILENCE_MSG 4066 - CONFIG_UBIFS_SILENCE_MSG 4067 4068 You will probably want to define these to avoid a really noisy system 4069 when storing the env in UBI. 4070 4071- CONFIG_ENV_IS_IN_MMC: 4072 4073 Define this if you have an MMC device which you want to use for the 4074 environment. 4075 4076 - CONFIG_SYS_MMC_ENV_DEV: 4077 4078 Specifies which MMC device the environment is stored in. 4079 4080 - CONFIG_SYS_MMC_ENV_PART (optional): 4081 4082 Specifies which MMC partition the environment is stored in. If not 4083 set, defaults to partition 0, the user area. Common values might be 4084 1 (first MMC boot partition), 2 (second MMC boot partition). 4085 4086 - CONFIG_ENV_OFFSET: 4087 - CONFIG_ENV_SIZE: 4088 4089 These two #defines specify the offset and size of the environment 4090 area within the specified MMC device. 4091 4092 If offset is positive (the usual case), it is treated as relative to 4093 the start of the MMC partition. If offset is negative, it is treated 4094 as relative to the end of the MMC partition. This can be useful if 4095 your board may be fitted with different MMC devices, which have 4096 different sizes for the MMC partitions, and you always want the 4097 environment placed at the very end of the partition, to leave the 4098 maximum possible space before it, to store other data. 4099 4100 These two values are in units of bytes, but must be aligned to an 4101 MMC sector boundary. 4102 4103 - CONFIG_ENV_OFFSET_REDUND (optional): 4104 4105 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 4106 hold a redundant copy of the environment data. This provides a 4107 valid backup copy in case the other copy is corrupted, e.g. due 4108 to a power failure during a "saveenv" operation. 4109 4110 This value may also be positive or negative; this is handled in the 4111 same way as CONFIG_ENV_OFFSET. 4112 4113 This value is also in units of bytes, but must also be aligned to 4114 an MMC sector boundary. 4115 4116 - CONFIG_ENV_SIZE_REDUND (optional): 4117 4118 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4119 set. If this value is set, it must be set to the same value as 4120 CONFIG_ENV_SIZE. 4121 4122- CONFIG_SYS_SPI_INIT_OFFSET 4123 4124 Defines offset to the initial SPI buffer area in DPRAM. The 4125 area is used at an early stage (ROM part) if the environment 4126 is configured to reside in the SPI EEPROM: We need a 520 byte 4127 scratch DPRAM area. It is used between the two initialization 4128 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4129 to be a good choice since it makes it far enough from the 4130 start of the data area as well as from the stack pointer. 4131 4132Please note that the environment is read-only until the monitor 4133has been relocated to RAM and a RAM copy of the environment has been 4134created; also, when using EEPROM you will have to use getenv_f() 4135until then to read environment variables. 4136 4137The environment is protected by a CRC32 checksum. Before the monitor 4138is relocated into RAM, as a result of a bad CRC you will be working 4139with the compiled-in default environment - *silently*!!! [This is 4140necessary, because the first environment variable we need is the 4141"baudrate" setting for the console - if we have a bad CRC, we don't 4142have any device yet where we could complain.] 4143 4144Note: once the monitor has been relocated, then it will complain if 4145the default environment is used; a new CRC is computed as soon as you 4146use the "saveenv" command to store a valid environment. 4147 4148- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4149 Echo the inverted Ethernet link state to the fault LED. 4150 4151 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4152 also needs to be defined. 4153 4154- CONFIG_SYS_FAULT_MII_ADDR: 4155 MII address of the PHY to check for the Ethernet link state. 4156 4157- CONFIG_NS16550_MIN_FUNCTIONS: 4158 Define this if you desire to only have use of the NS16550_init 4159 and NS16550_putc functions for the serial driver located at 4160 drivers/serial/ns16550.c. This option is useful for saving 4161 space for already greatly restricted images, including but not 4162 limited to NAND_SPL configurations. 4163 4164- CONFIG_DISPLAY_BOARDINFO 4165 Display information about the board that U-Boot is running on 4166 when U-Boot starts up. The board function checkboard() is called 4167 to do this. 4168 4169- CONFIG_DISPLAY_BOARDINFO_LATE 4170 Similar to the previous option, but display this information 4171 later, once stdio is running and output goes to the LCD, if 4172 present. 4173 4174Low Level (hardware related) configuration options: 4175--------------------------------------------------- 4176 4177- CONFIG_SYS_CACHELINE_SIZE: 4178 Cache Line Size of the CPU. 4179 4180- CONFIG_SYS_DEFAULT_IMMR: 4181 Default address of the IMMR after system reset. 4182 4183 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4184 and RPXsuper) to be able to adjust the position of 4185 the IMMR register after a reset. 4186 4187- CONFIG_SYS_CCSRBAR_DEFAULT: 4188 Default (power-on reset) physical address of CCSR on Freescale 4189 PowerPC SOCs. 4190 4191- CONFIG_SYS_CCSRBAR: 4192 Virtual address of CCSR. On a 32-bit build, this is typically 4193 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4194 4195 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4196 for cross-platform code that uses that macro instead. 4197 4198- CONFIG_SYS_CCSRBAR_PHYS: 4199 Physical address of CCSR. CCSR can be relocated to a new 4200 physical address, if desired. In this case, this macro should 4201 be set to that address. Otherwise, it should be set to the 4202 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4203 is typically relocated on 36-bit builds. It is recommended 4204 that this macro be defined via the _HIGH and _LOW macros: 4205 4206 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4207 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4208 4209- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4210 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4211 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4212 used in assembly code, so it must not contain typecasts or 4213 integer size suffixes (e.g. "ULL"). 4214 4215- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4216 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4217 used in assembly code, so it must not contain typecasts or 4218 integer size suffixes (e.g. "ULL"). 4219 4220- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4221 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4222 forced to a value that ensures that CCSR is not relocated. 4223 4224- Floppy Disk Support: 4225 CONFIG_SYS_FDC_DRIVE_NUMBER 4226 4227 the default drive number (default value 0) 4228 4229 CONFIG_SYS_ISA_IO_STRIDE 4230 4231 defines the spacing between FDC chipset registers 4232 (default value 1) 4233 4234 CONFIG_SYS_ISA_IO_OFFSET 4235 4236 defines the offset of register from address. It 4237 depends on which part of the data bus is connected to 4238 the FDC chipset. (default value 0) 4239 4240 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4241 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4242 default value. 4243 4244 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4245 fdc_hw_init() is called at the beginning of the FDC 4246 setup. fdc_hw_init() must be provided by the board 4247 source code. It is used to make hardware dependant 4248 initializations. 4249 4250- CONFIG_IDE_AHB: 4251 Most IDE controllers were designed to be connected with PCI 4252 interface. Only few of them were designed for AHB interface. 4253 When software is doing ATA command and data transfer to 4254 IDE devices through IDE-AHB controller, some additional 4255 registers accessing to these kind of IDE-AHB controller 4256 is requierd. 4257 4258- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4259 DO NOT CHANGE unless you know exactly what you're 4260 doing! (11-4) [MPC8xx/82xx systems only] 4261 4262- CONFIG_SYS_INIT_RAM_ADDR: 4263 4264 Start address of memory area that can be used for 4265 initial data and stack; please note that this must be 4266 writable memory that is working WITHOUT special 4267 initialization, i. e. you CANNOT use normal RAM which 4268 will become available only after programming the 4269 memory controller and running certain initialization 4270 sequences. 4271 4272 U-Boot uses the following memory types: 4273 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4274 - MPC824X: data cache 4275 - PPC4xx: data cache 4276 4277- CONFIG_SYS_GBL_DATA_OFFSET: 4278 4279 Offset of the initial data structure in the memory 4280 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4281 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4282 data is located at the end of the available space 4283 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4284 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 4285 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4286 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4287 4288 Note: 4289 On the MPC824X (or other systems that use the data 4290 cache for initial memory) the address chosen for 4291 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4292 point to an otherwise UNUSED address space between 4293 the top of RAM and the start of the PCI space. 4294 4295- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4296 4297- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4298 4299- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4300 4301- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4302 4303- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4304 4305- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4306 4307- CONFIG_SYS_OR_TIMING_SDRAM: 4308 SDRAM timing 4309 4310- CONFIG_SYS_MAMR_PTA: 4311 periodic timer for refresh 4312 4313- CONFIG_SYS_DER: Debug Event Register (37-47) 4314 4315- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4316 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4317 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4318 CONFIG_SYS_BR1_PRELIM: 4319 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4320 4321- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4322 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4323 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4324 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4325 4326- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4327 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4328 Machine Mode Register and Memory Periodic Timer 4329 Prescaler definitions (SDRAM timing) 4330 4331- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4332 enable I2C microcode relocation patch (MPC8xx); 4333 define relocation offset in DPRAM [DSP2] 4334 4335- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4336 enable SMC microcode relocation patch (MPC8xx); 4337 define relocation offset in DPRAM [SMC1] 4338 4339- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4340 enable SPI microcode relocation patch (MPC8xx); 4341 define relocation offset in DPRAM [SCC4] 4342 4343- CONFIG_SYS_USE_OSCCLK: 4344 Use OSCM clock mode on MBX8xx board. Be careful, 4345 wrong setting might damage your board. Read 4346 doc/README.MBX before setting this variable! 4347 4348- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4349 Offset of the bootmode word in DPRAM used by post 4350 (Power On Self Tests). This definition overrides 4351 #define'd default value in commproc.h resp. 4352 cpm_8260.h. 4353 4354- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4355 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4356 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4357 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4358 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4359 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4360 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4361 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4362 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4363 4364- CONFIG_PCI_DISABLE_PCIE: 4365 Disable PCI-Express on systems where it is supported but not 4366 required. 4367 4368- CONFIG_PCI_ENUM_ONLY 4369 Only scan through and get the devices on the busses. 4370 Don't do any setup work, presumably because someone or 4371 something has already done it, and we don't need to do it 4372 a second time. Useful for platforms that are pre-booted 4373 by coreboot or similar. 4374 4375- CONFIG_PCI_INDIRECT_BRIDGE: 4376 Enable support for indirect PCI bridges. 4377 4378- CONFIG_SYS_SRIO: 4379 Chip has SRIO or not 4380 4381- CONFIG_SRIO1: 4382 Board has SRIO 1 port available 4383 4384- CONFIG_SRIO2: 4385 Board has SRIO 2 port available 4386 4387- CONFIG_SRIO_PCIE_BOOT_MASTER 4388 Board can support master function for Boot from SRIO and PCIE 4389 4390- CONFIG_SYS_SRIOn_MEM_VIRT: 4391 Virtual Address of SRIO port 'n' memory region 4392 4393- CONFIG_SYS_SRIOn_MEM_PHYS: 4394 Physical Address of SRIO port 'n' memory region 4395 4396- CONFIG_SYS_SRIOn_MEM_SIZE: 4397 Size of SRIO port 'n' memory region 4398 4399- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4400 Defined to tell the NAND controller that the NAND chip is using 4401 a 16 bit bus. 4402 Not all NAND drivers use this symbol. 4403 Example of drivers that use it: 4404 - drivers/mtd/nand/ndfc.c 4405 - drivers/mtd/nand/mxc_nand.c 4406 4407- CONFIG_SYS_NDFC_EBC0_CFG 4408 Sets the EBC0_CFG register for the NDFC. If not defined 4409 a default value will be used. 4410 4411- CONFIG_SPD_EEPROM 4412 Get DDR timing information from an I2C EEPROM. Common 4413 with pluggable memory modules such as SODIMMs 4414 4415 SPD_EEPROM_ADDRESS 4416 I2C address of the SPD EEPROM 4417 4418- CONFIG_SYS_SPD_BUS_NUM 4419 If SPD EEPROM is on an I2C bus other than the first 4420 one, specify here. Note that the value must resolve 4421 to something your driver can deal with. 4422 4423- CONFIG_SYS_DDR_RAW_TIMING 4424 Get DDR timing information from other than SPD. Common with 4425 soldered DDR chips onboard without SPD. DDR raw timing 4426 parameters are extracted from datasheet and hard-coded into 4427 header files or board specific files. 4428 4429- CONFIG_FSL_DDR_INTERACTIVE 4430 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4431 4432- CONFIG_SYS_83XX_DDR_USES_CS0 4433 Only for 83xx systems. If specified, then DDR should 4434 be configured using CS0 and CS1 instead of CS2 and CS3. 4435 4436- CONFIG_ETHER_ON_FEC[12] 4437 Define to enable FEC[12] on a 8xx series processor. 4438 4439- CONFIG_FEC[12]_PHY 4440 Define to the hardcoded PHY address which corresponds 4441 to the given FEC; i. e. 4442 #define CONFIG_FEC1_PHY 4 4443 means that the PHY with address 4 is connected to FEC1 4444 4445 When set to -1, means to probe for first available. 4446 4447- CONFIG_FEC[12]_PHY_NORXERR 4448 The PHY does not have a RXERR line (RMII only). 4449 (so program the FEC to ignore it). 4450 4451- CONFIG_RMII 4452 Enable RMII mode for all FECs. 4453 Note that this is a global option, we can't 4454 have one FEC in standard MII mode and another in RMII mode. 4455 4456- CONFIG_CRC32_VERIFY 4457 Add a verify option to the crc32 command. 4458 The syntax is: 4459 4460 => crc32 -v <address> <count> <crc32> 4461 4462 Where address/count indicate a memory area 4463 and crc32 is the correct crc32 which the 4464 area should have. 4465 4466- CONFIG_LOOPW 4467 Add the "loopw" memory command. This only takes effect if 4468 the memory commands are activated globally (CONFIG_CMD_MEM). 4469 4470- CONFIG_MX_CYCLIC 4471 Add the "mdc" and "mwc" memory commands. These are cyclic 4472 "md/mw" commands. 4473 Examples: 4474 4475 => mdc.b 10 4 500 4476 This command will print 4 bytes (10,11,12,13) each 500 ms. 4477 4478 => mwc.l 100 12345678 10 4479 This command will write 12345678 to address 100 all 10 ms. 4480 4481 This only takes effect if the memory commands are activated 4482 globally (CONFIG_CMD_MEM). 4483 4484- CONFIG_SKIP_LOWLEVEL_INIT 4485 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4486 low level initializations (like setting up the memory 4487 controller) are omitted and/or U-Boot does not 4488 relocate itself into RAM. 4489 4490 Normally this variable MUST NOT be defined. The only 4491 exception is when U-Boot is loaded (to RAM) by some 4492 other boot loader or by a debugger which performs 4493 these initializations itself. 4494 4495- CONFIG_SPL_BUILD 4496 Modifies the behaviour of start.S when compiling a loader 4497 that is executed before the actual U-Boot. E.g. when 4498 compiling a NAND SPL. 4499 4500- CONFIG_TPL_BUILD 4501 Modifies the behaviour of start.S when compiling a loader 4502 that is executed after the SPL and before the actual U-Boot. 4503 It is loaded by the SPL. 4504 4505- CONFIG_SYS_MPC85XX_NO_RESETVEC 4506 Only for 85xx systems. If this variable is specified, the section 4507 .resetvec is not kept and the section .bootpg is placed in the 4508 previous 4k of the .text section. 4509 4510- CONFIG_ARCH_MAP_SYSMEM 4511 Generally U-Boot (and in particular the md command) uses 4512 effective address. It is therefore not necessary to regard 4513 U-Boot address as virtual addresses that need to be translated 4514 to physical addresses. However, sandbox requires this, since 4515 it maintains its own little RAM buffer which contains all 4516 addressable memory. This option causes some memory accesses 4517 to be mapped through map_sysmem() / unmap_sysmem(). 4518 4519- CONFIG_USE_ARCH_MEMCPY 4520 CONFIG_USE_ARCH_MEMSET 4521 If these options are used a optimized version of memcpy/memset will 4522 be used if available. These functions may be faster under some 4523 conditions but may increase the binary size. 4524 4525- CONFIG_X86_RESET_VECTOR 4526 If defined, the x86 reset vector code is included. This is not 4527 needed when U-Boot is running from Coreboot. 4528 4529- CONFIG_SYS_MPUCLK 4530 Defines the MPU clock speed (in MHz). 4531 4532 NOTE : currently only supported on AM335x platforms. 4533 4534- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4535 Enables the RTC32K OSC on AM33xx based plattforms 4536 4537Freescale QE/FMAN Firmware Support: 4538----------------------------------- 4539 4540The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4541loading of "firmware", which is encoded in the QE firmware binary format. 4542This firmware often needs to be loaded during U-Boot booting, so macros 4543are used to identify the storage device (NOR flash, SPI, etc) and the address 4544within that device. 4545 4546- CONFIG_SYS_FMAN_FW_ADDR 4547 The address in the storage device where the FMAN microcode is located. The 4548 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4549 is also specified. 4550 4551- CONFIG_SYS_QE_FW_ADDR 4552 The address in the storage device where the QE microcode is located. The 4553 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4554 is also specified. 4555 4556- CONFIG_SYS_QE_FMAN_FW_LENGTH 4557 The maximum possible size of the firmware. The firmware binary format 4558 has a field that specifies the actual size of the firmware, but it 4559 might not be possible to read any part of the firmware unless some 4560 local storage is allocated to hold the entire firmware first. 4561 4562- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4563 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4564 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4565 virtual address in NOR flash. 4566 4567- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4568 Specifies that QE/FMAN firmware is located in NAND flash. 4569 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4570 4571- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4572 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4573 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4574 4575- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 4576 Specifies that QE/FMAN firmware is located on the primary SPI 4577 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4578 4579- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4580 Specifies that QE/FMAN firmware is located in the remote (master) 4581 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4582 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4583 window->master inbound window->master LAW->the ucode address in 4584 master's memory space. 4585 4586Building the Software: 4587====================== 4588 4589Building U-Boot has been tested in several native build environments 4590and in many different cross environments. Of course we cannot support 4591all possibly existing versions of cross development tools in all 4592(potentially obsolete) versions. In case of tool chain problems we 4593recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4594which is extensively used to build and test U-Boot. 4595 4596If you are not using a native environment, it is assumed that you 4597have GNU cross compiling tools available in your path. In this case, 4598you must set the environment variable CROSS_COMPILE in your shell. 4599Note that no changes to the Makefile or any other source files are 4600necessary. For example using the ELDK on a 4xx CPU, please enter: 4601 4602 $ CROSS_COMPILE=ppc_4xx- 4603 $ export CROSS_COMPILE 4604 4605Note: If you wish to generate Windows versions of the utilities in 4606 the tools directory you can use the MinGW toolchain 4607 (http://www.mingw.org). Set your HOST tools to the MinGW 4608 toolchain and execute 'make tools'. For example: 4609 4610 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4611 4612 Binaries such as tools/mkimage.exe will be created which can 4613 be executed on computers running Windows. 4614 4615U-Boot is intended to be simple to build. After installing the 4616sources you must configure U-Boot for one specific board type. This 4617is done by typing: 4618 4619 make NAME_config 4620 4621where "NAME_config" is the name of one of the existing configu- 4622rations; see boards.cfg for supported names. 4623 4624Note: for some board special configuration names may exist; check if 4625 additional information is available from the board vendor; for 4626 instance, the TQM823L systems are available without (standard) 4627 or with LCD support. You can select such additional "features" 4628 when choosing the configuration, i. e. 4629 4630 make TQM823L_config 4631 - will configure for a plain TQM823L, i. e. no LCD support 4632 4633 make TQM823L_LCD_config 4634 - will configure for a TQM823L with U-Boot console on LCD 4635 4636 etc. 4637 4638 4639Finally, type "make all", and you should get some working U-Boot 4640images ready for download to / installation on your system: 4641 4642- "u-boot.bin" is a raw binary image 4643- "u-boot" is an image in ELF binary format 4644- "u-boot.srec" is in Motorola S-Record format 4645 4646By default the build is performed locally and the objects are saved 4647in the source directory. One of the two methods can be used to change 4648this behavior and build U-Boot to some external directory: 4649 46501. Add O= to the make command line invocations: 4651 4652 make O=/tmp/build distclean 4653 make O=/tmp/build NAME_config 4654 make O=/tmp/build all 4655 46562. Set environment variable BUILD_DIR to point to the desired location: 4657 4658 export BUILD_DIR=/tmp/build 4659 make distclean 4660 make NAME_config 4661 make all 4662 4663Note that the command line "O=" setting overrides the BUILD_DIR environment 4664variable. 4665 4666 4667Please be aware that the Makefiles assume you are using GNU make, so 4668for instance on NetBSD you might need to use "gmake" instead of 4669native "make". 4670 4671 4672If the system board that you have is not listed, then you will need 4673to port U-Boot to your hardware platform. To do this, follow these 4674steps: 4675 46761. Add a new configuration option for your board to the toplevel 4677 "boards.cfg" file, using the existing entries as examples. 4678 Follow the instructions there to keep the boards in order. 46792. Create a new directory to hold your board specific code. Add any 4680 files you need. In your board directory, you will need at least 4681 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 46823. Create a new configuration file "include/configs/<board>.h" for 4683 your board 46843. If you're porting U-Boot to a new CPU, then also create a new 4685 directory to hold your CPU specific code. Add any files you need. 46864. Run "make <board>_config" with your new name. 46875. Type "make", and you should get a working "u-boot.srec" file 4688 to be installed on your target system. 46896. Debug and solve any problems that might arise. 4690 [Of course, this last step is much harder than it sounds.] 4691 4692 4693Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4694============================================================== 4695 4696If you have modified U-Boot sources (for instance added a new board 4697or support for new devices, a new CPU, etc.) you are expected to 4698provide feedback to the other developers. The feedback normally takes 4699the form of a "patch", i. e. a context diff against a certain (latest 4700official or latest in the git repository) version of U-Boot sources. 4701 4702But before you submit such a patch, please verify that your modifi- 4703cation did not break existing code. At least make sure that *ALL* of 4704the supported boards compile WITHOUT ANY compiler warnings. To do so, 4705just run the "MAKEALL" script, which will configure and build U-Boot 4706for ALL supported system. Be warned, this will take a while. You can 4707select which (cross) compiler to use by passing a `CROSS_COMPILE' 4708environment variable to the script, i. e. to use the ELDK cross tools 4709you can type 4710 4711 CROSS_COMPILE=ppc_8xx- MAKEALL 4712 4713or to build on a native PowerPC system you can type 4714 4715 CROSS_COMPILE=' ' MAKEALL 4716 4717When using the MAKEALL script, the default behaviour is to build 4718U-Boot in the source directory. This location can be changed by 4719setting the BUILD_DIR environment variable. Also, for each target 4720built, the MAKEALL script saves two log files (<target>.ERR and 4721<target>.MAKEALL) in the <source dir>/LOG directory. This default 4722location can be changed by setting the MAKEALL_LOGDIR environment 4723variable. For example: 4724 4725 export BUILD_DIR=/tmp/build 4726 export MAKEALL_LOGDIR=/tmp/log 4727 CROSS_COMPILE=ppc_8xx- MAKEALL 4728 4729With the above settings build objects are saved in the /tmp/build, 4730log files are saved in the /tmp/log and the source tree remains clean 4731during the whole build process. 4732 4733 4734See also "U-Boot Porting Guide" below. 4735 4736 4737Monitor Commands - Overview: 4738============================ 4739 4740go - start application at address 'addr' 4741run - run commands in an environment variable 4742bootm - boot application image from memory 4743bootp - boot image via network using BootP/TFTP protocol 4744bootz - boot zImage from memory 4745tftpboot- boot image via network using TFTP protocol 4746 and env variables "ipaddr" and "serverip" 4747 (and eventually "gatewayip") 4748tftpput - upload a file via network using TFTP protocol 4749rarpboot- boot image via network using RARP/TFTP protocol 4750diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4751loads - load S-Record file over serial line 4752loadb - load binary file over serial line (kermit mode) 4753md - memory display 4754mm - memory modify (auto-incrementing) 4755nm - memory modify (constant address) 4756mw - memory write (fill) 4757cp - memory copy 4758cmp - memory compare 4759crc32 - checksum calculation 4760i2c - I2C sub-system 4761sspi - SPI utility commands 4762base - print or set address offset 4763printenv- print environment variables 4764setenv - set environment variables 4765saveenv - save environment variables to persistent storage 4766protect - enable or disable FLASH write protection 4767erase - erase FLASH memory 4768flinfo - print FLASH memory information 4769nand - NAND memory operations (see doc/README.nand) 4770bdinfo - print Board Info structure 4771iminfo - print header information for application image 4772coninfo - print console devices and informations 4773ide - IDE sub-system 4774loop - infinite loop on address range 4775loopw - infinite write loop on address range 4776mtest - simple RAM test 4777icache - enable or disable instruction cache 4778dcache - enable or disable data cache 4779reset - Perform RESET of the CPU 4780echo - echo args to console 4781version - print monitor version 4782help - print online help 4783? - alias for 'help' 4784 4785 4786Monitor Commands - Detailed Description: 4787======================================== 4788 4789TODO. 4790 4791For now: just type "help <command>". 4792 4793 4794Environment Variables: 4795====================== 4796 4797U-Boot supports user configuration using Environment Variables which 4798can be made persistent by saving to Flash memory. 4799 4800Environment Variables are set using "setenv", printed using 4801"printenv", and saved to Flash using "saveenv". Using "setenv" 4802without a value can be used to delete a variable from the 4803environment. As long as you don't save the environment you are 4804working with an in-memory copy. In case the Flash area containing the 4805environment is erased by accident, a default environment is provided. 4806 4807Some configuration options can be set using Environment Variables. 4808 4809List of environment variables (most likely not complete): 4810 4811 baudrate - see CONFIG_BAUDRATE 4812 4813 bootdelay - see CONFIG_BOOTDELAY 4814 4815 bootcmd - see CONFIG_BOOTCOMMAND 4816 4817 bootargs - Boot arguments when booting an RTOS image 4818 4819 bootfile - Name of the image to load with TFTP 4820 4821 bootm_low - Memory range available for image processing in the bootm 4822 command can be restricted. This variable is given as 4823 a hexadecimal number and defines lowest address allowed 4824 for use by the bootm command. See also "bootm_size" 4825 environment variable. Address defined by "bootm_low" is 4826 also the base of the initial memory mapping for the Linux 4827 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4828 bootm_mapsize. 4829 4830 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4831 This variable is given as a hexadecimal number and it 4832 defines the size of the memory region starting at base 4833 address bootm_low that is accessible by the Linux kernel 4834 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4835 as the default value if it is defined, and bootm_size is 4836 used otherwise. 4837 4838 bootm_size - Memory range available for image processing in the bootm 4839 command can be restricted. This variable is given as 4840 a hexadecimal number and defines the size of the region 4841 allowed for use by the bootm command. See also "bootm_low" 4842 environment variable. 4843 4844 updatefile - Location of the software update file on a TFTP server, used 4845 by the automatic software update feature. Please refer to 4846 documentation in doc/README.update for more details. 4847 4848 autoload - if set to "no" (any string beginning with 'n'), 4849 "bootp" will just load perform a lookup of the 4850 configuration from the BOOTP server, but not try to 4851 load any image using TFTP 4852 4853 autostart - if set to "yes", an image loaded using the "bootp", 4854 "rarpboot", "tftpboot" or "diskboot" commands will 4855 be automatically started (by internally calling 4856 "bootm") 4857 4858 If set to "no", a standalone image passed to the 4859 "bootm" command will be copied to the load address 4860 (and eventually uncompressed), but NOT be started. 4861 This can be used to load and uncompress arbitrary 4862 data. 4863 4864 fdt_high - if set this restricts the maximum address that the 4865 flattened device tree will be copied into upon boot. 4866 For example, if you have a system with 1 GB memory 4867 at physical address 0x10000000, while Linux kernel 4868 only recognizes the first 704 MB as low memory, you 4869 may need to set fdt_high as 0x3C000000 to have the 4870 device tree blob be copied to the maximum address 4871 of the 704 MB low memory, so that Linux kernel can 4872 access it during the boot procedure. 4873 4874 If this is set to the special value 0xFFFFFFFF then 4875 the fdt will not be copied at all on boot. For this 4876 to work it must reside in writable memory, have 4877 sufficient padding on the end of it for u-boot to 4878 add the information it needs into it, and the memory 4879 must be accessible by the kernel. 4880 4881 fdtcontroladdr- if set this is the address of the control flattened 4882 device tree used by U-Boot when CONFIG_OF_CONTROL is 4883 defined. 4884 4885 i2cfast - (PPC405GP|PPC405EP only) 4886 if set to 'y' configures Linux I2C driver for fast 4887 mode (400kHZ). This environment variable is used in 4888 initialization code. So, for changes to be effective 4889 it must be saved and board must be reset. 4890 4891 initrd_high - restrict positioning of initrd images: 4892 If this variable is not set, initrd images will be 4893 copied to the highest possible address in RAM; this 4894 is usually what you want since it allows for 4895 maximum initrd size. If for some reason you want to 4896 make sure that the initrd image is loaded below the 4897 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4898 variable to a value of "no" or "off" or "0". 4899 Alternatively, you can set it to a maximum upper 4900 address to use (U-Boot will still check that it 4901 does not overwrite the U-Boot stack and data). 4902 4903 For instance, when you have a system with 16 MB 4904 RAM, and want to reserve 4 MB from use by Linux, 4905 you can do this by adding "mem=12M" to the value of 4906 the "bootargs" variable. However, now you must make 4907 sure that the initrd image is placed in the first 4908 12 MB as well - this can be done with 4909 4910 setenv initrd_high 00c00000 4911 4912 If you set initrd_high to 0xFFFFFFFF, this is an 4913 indication to U-Boot that all addresses are legal 4914 for the Linux kernel, including addresses in flash 4915 memory. In this case U-Boot will NOT COPY the 4916 ramdisk at all. This may be useful to reduce the 4917 boot time on your system, but requires that this 4918 feature is supported by your Linux kernel. 4919 4920 ipaddr - IP address; needed for tftpboot command 4921 4922 loadaddr - Default load address for commands like "bootp", 4923 "rarpboot", "tftpboot", "loadb" or "diskboot" 4924 4925 loads_echo - see CONFIG_LOADS_ECHO 4926 4927 serverip - TFTP server IP address; needed for tftpboot command 4928 4929 bootretry - see CONFIG_BOOT_RETRY_TIME 4930 4931 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4932 4933 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4934 4935 ethprime - controls which interface is used first. 4936 4937 ethact - controls which interface is currently active. 4938 For example you can do the following 4939 4940 => setenv ethact FEC 4941 => ping 192.168.0.1 # traffic sent on FEC 4942 => setenv ethact SCC 4943 => ping 10.0.0.1 # traffic sent on SCC 4944 4945 ethrotate - When set to "no" U-Boot does not go through all 4946 available network interfaces. 4947 It just stays at the currently selected interface. 4948 4949 netretry - When set to "no" each network operation will 4950 either succeed or fail without retrying. 4951 When set to "once" the network operation will 4952 fail when all the available network interfaces 4953 are tried once without success. 4954 Useful on scripts which control the retry operation 4955 themselves. 4956 4957 npe_ucode - set load address for the NPE microcode 4958 4959 silent_linux - If set then linux will be told to boot silently, by 4960 changing the console to be empty. If "yes" it will be 4961 made silent. If "no" it will not be made silent. If 4962 unset, then it will be made silent if the U-Boot console 4963 is silent. 4964 4965 tftpsrcport - If this is set, the value is used for TFTP's 4966 UDP source port. 4967 4968 tftpdstport - If this is set, the value is used for TFTP's UDP 4969 destination port instead of the Well Know Port 69. 4970 4971 tftpblocksize - Block size to use for TFTP transfers; if not set, 4972 we use the TFTP server's default block size 4973 4974 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4975 seconds, minimum value is 1000 = 1 second). Defines 4976 when a packet is considered to be lost so it has to 4977 be retransmitted. The default is 5000 = 5 seconds. 4978 Lowering this value may make downloads succeed 4979 faster in networks with high packet loss rates or 4980 with unreliable TFTP servers. 4981 4982 vlan - When set to a value < 4095 the traffic over 4983 Ethernet is encapsulated/received over 802.1q 4984 VLAN tagged frames. 4985 4986The following image location variables contain the location of images 4987used in booting. The "Image" column gives the role of the image and is 4988not an environment variable name. The other columns are environment 4989variable names. "File Name" gives the name of the file on a TFTP 4990server, "RAM Address" gives the location in RAM the image will be 4991loaded to, and "Flash Location" gives the image's address in NOR 4992flash or offset in NAND flash. 4993 4994*Note* - these variables don't have to be defined for all boards, some 4995boards currenlty use other variables for these purposes, and some 4996boards use these variables for other purposes. 4997 4998Image File Name RAM Address Flash Location 4999----- --------- ----------- -------------- 5000u-boot u-boot u-boot_addr_r u-boot_addr 5001Linux kernel bootfile kernel_addr_r kernel_addr 5002device tree blob fdtfile fdt_addr_r fdt_addr 5003ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 5004 5005The following environment variables may be used and automatically 5006updated by the network boot commands ("bootp" and "rarpboot"), 5007depending the information provided by your boot server: 5008 5009 bootfile - see above 5010 dnsip - IP address of your Domain Name Server 5011 dnsip2 - IP address of your secondary Domain Name Server 5012 gatewayip - IP address of the Gateway (Router) to use 5013 hostname - Target hostname 5014 ipaddr - see above 5015 netmask - Subnet Mask 5016 rootpath - Pathname of the root filesystem on the NFS server 5017 serverip - see above 5018 5019 5020There are two special Environment Variables: 5021 5022 serial# - contains hardware identification information such 5023 as type string and/or serial number 5024 ethaddr - Ethernet address 5025 5026These variables can be set only once (usually during manufacturing of 5027the board). U-Boot refuses to delete or overwrite these variables 5028once they have been set once. 5029 5030 5031Further special Environment Variables: 5032 5033 ver - Contains the U-Boot version string as printed 5034 with the "version" command. This variable is 5035 readonly (see CONFIG_VERSION_VARIABLE). 5036 5037 5038Please note that changes to some configuration parameters may take 5039only effect after the next boot (yes, that's just like Windoze :-). 5040 5041 5042Callback functions for environment variables: 5043--------------------------------------------- 5044 5045For some environment variables, the behavior of u-boot needs to change 5046when their values are changed. This functionailty allows functions to 5047be associated with arbitrary variables. On creation, overwrite, or 5048deletion, the callback will provide the opportunity for some side 5049effect to happen or for the change to be rejected. 5050 5051The callbacks are named and associated with a function using the 5052U_BOOT_ENV_CALLBACK macro in your board or driver code. 5053 5054These callbacks are associated with variables in one of two ways. The 5055static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 5056in the board configuration to a string that defines a list of 5057associations. The list must be in the following format: 5058 5059 entry = variable_name[:callback_name] 5060 list = entry[,list] 5061 5062If the callback name is not specified, then the callback is deleted. 5063Spaces are also allowed anywhere in the list. 5064 5065Callbacks can also be associated by defining the ".callbacks" variable 5066with the same list format above. Any association in ".callbacks" will 5067override any association in the static list. You can define 5068CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 5069".callbacks" envirnoment variable in the default or embedded environment. 5070 5071 5072Command Line Parsing: 5073===================== 5074 5075There are two different command line parsers available with U-Boot: 5076the old "simple" one, and the much more powerful "hush" shell: 5077 5078Old, simple command line parser: 5079-------------------------------- 5080 5081- supports environment variables (through setenv / saveenv commands) 5082- several commands on one line, separated by ';' 5083- variable substitution using "... ${name} ..." syntax 5084- special characters ('$', ';') can be escaped by prefixing with '\', 5085 for example: 5086 setenv bootcmd bootm \${address} 5087- You can also escape text by enclosing in single apostrophes, for example: 5088 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 5089 5090Hush shell: 5091----------- 5092 5093- similar to Bourne shell, with control structures like 5094 if...then...else...fi, for...do...done; while...do...done, 5095 until...do...done, ... 5096- supports environment ("global") variables (through setenv / saveenv 5097 commands) and local shell variables (through standard shell syntax 5098 "name=value"); only environment variables can be used with "run" 5099 command 5100 5101General rules: 5102-------------- 5103 5104(1) If a command line (or an environment variable executed by a "run" 5105 command) contains several commands separated by semicolon, and 5106 one of these commands fails, then the remaining commands will be 5107 executed anyway. 5108 5109(2) If you execute several variables with one call to run (i. e. 5110 calling run with a list of variables as arguments), any failing 5111 command will cause "run" to terminate, i. e. the remaining 5112 variables are not executed. 5113 5114Note for Redundant Ethernet Interfaces: 5115======================================= 5116 5117Some boards come with redundant Ethernet interfaces; U-Boot supports 5118such configurations and is capable of automatic selection of a 5119"working" interface when needed. MAC assignment works as follows: 5120 5121Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5122MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5123"eth1addr" (=>eth1), "eth2addr", ... 5124 5125If the network interface stores some valid MAC address (for instance 5126in SROM), this is used as default address if there is NO correspon- 5127ding setting in the environment; if the corresponding environment 5128variable is set, this overrides the settings in the card; that means: 5129 5130o If the SROM has a valid MAC address, and there is no address in the 5131 environment, the SROM's address is used. 5132 5133o If there is no valid address in the SROM, and a definition in the 5134 environment exists, then the value from the environment variable is 5135 used. 5136 5137o If both the SROM and the environment contain a MAC address, and 5138 both addresses are the same, this MAC address is used. 5139 5140o If both the SROM and the environment contain a MAC address, and the 5141 addresses differ, the value from the environment is used and a 5142 warning is printed. 5143 5144o If neither SROM nor the environment contain a MAC address, an error 5145 is raised. 5146 5147If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5148will be programmed into hardware as part of the initialization process. This 5149may be skipped by setting the appropriate 'ethmacskip' environment variable. 5150The naming convention is as follows: 5151"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5152 5153Image Formats: 5154============== 5155 5156U-Boot is capable of booting (and performing other auxiliary operations on) 5157images in two formats: 5158 5159New uImage format (FIT) 5160----------------------- 5161 5162Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5163to Flattened Device Tree). It allows the use of images with multiple 5164components (several kernels, ramdisks, etc.), with contents protected by 5165SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5166 5167 5168Old uImage format 5169----------------- 5170 5171Old image format is based on binary files which can be basically anything, 5172preceded by a special header; see the definitions in include/image.h for 5173details; basically, the header defines the following image properties: 5174 5175* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5176 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5177 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5178 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5179 INTEGRITY). 5180* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5181 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5182 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5183* Compression Type (uncompressed, gzip, bzip2) 5184* Load Address 5185* Entry Point 5186* Image Name 5187* Image Timestamp 5188 5189The header is marked by a special Magic Number, and both the header 5190and the data portions of the image are secured against corruption by 5191CRC32 checksums. 5192 5193 5194Linux Support: 5195============== 5196 5197Although U-Boot should support any OS or standalone application 5198easily, the main focus has always been on Linux during the design of 5199U-Boot. 5200 5201U-Boot includes many features that so far have been part of some 5202special "boot loader" code within the Linux kernel. Also, any 5203"initrd" images to be used are no longer part of one big Linux image; 5204instead, kernel and "initrd" are separate images. This implementation 5205serves several purposes: 5206 5207- the same features can be used for other OS or standalone 5208 applications (for instance: using compressed images to reduce the 5209 Flash memory footprint) 5210 5211- it becomes much easier to port new Linux kernel versions because 5212 lots of low-level, hardware dependent stuff are done by U-Boot 5213 5214- the same Linux kernel image can now be used with different "initrd" 5215 images; of course this also means that different kernel images can 5216 be run with the same "initrd". This makes testing easier (you don't 5217 have to build a new "zImage.initrd" Linux image when you just 5218 change a file in your "initrd"). Also, a field-upgrade of the 5219 software is easier now. 5220 5221 5222Linux HOWTO: 5223============ 5224 5225Porting Linux to U-Boot based systems: 5226--------------------------------------- 5227 5228U-Boot cannot save you from doing all the necessary modifications to 5229configure the Linux device drivers for use with your target hardware 5230(no, we don't intend to provide a full virtual machine interface to 5231Linux :-). 5232 5233But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5234 5235Just make sure your machine specific header file (for instance 5236include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5237Information structure as we define in include/asm-<arch>/u-boot.h, 5238and make sure that your definition of IMAP_ADDR uses the same value 5239as your U-Boot configuration in CONFIG_SYS_IMMR. 5240 5241 5242Configuring the Linux kernel: 5243----------------------------- 5244 5245No specific requirements for U-Boot. Make sure you have some root 5246device (initial ramdisk, NFS) for your target system. 5247 5248 5249Building a Linux Image: 5250----------------------- 5251 5252With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5253not used. If you use recent kernel source, a new build target 5254"uImage" will exist which automatically builds an image usable by 5255U-Boot. Most older kernels also have support for a "pImage" target, 5256which was introduced for our predecessor project PPCBoot and uses a 5257100% compatible format. 5258 5259Example: 5260 5261 make TQM850L_config 5262 make oldconfig 5263 make dep 5264 make uImage 5265 5266The "uImage" build target uses a special tool (in 'tools/mkimage') to 5267encapsulate a compressed Linux kernel image with header information, 5268CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5269 5270* build a standard "vmlinux" kernel image (in ELF binary format): 5271 5272* convert the kernel into a raw binary image: 5273 5274 ${CROSS_COMPILE}-objcopy -O binary \ 5275 -R .note -R .comment \ 5276 -S vmlinux linux.bin 5277 5278* compress the binary image: 5279 5280 gzip -9 linux.bin 5281 5282* package compressed binary image for U-Boot: 5283 5284 mkimage -A ppc -O linux -T kernel -C gzip \ 5285 -a 0 -e 0 -n "Linux Kernel Image" \ 5286 -d linux.bin.gz uImage 5287 5288 5289The "mkimage" tool can also be used to create ramdisk images for use 5290with U-Boot, either separated from the Linux kernel image, or 5291combined into one file. "mkimage" encapsulates the images with a 64 5292byte header containing information about target architecture, 5293operating system, image type, compression method, entry points, time 5294stamp, CRC32 checksums, etc. 5295 5296"mkimage" can be called in two ways: to verify existing images and 5297print the header information, or to build new images. 5298 5299In the first form (with "-l" option) mkimage lists the information 5300contained in the header of an existing U-Boot image; this includes 5301checksum verification: 5302 5303 tools/mkimage -l image 5304 -l ==> list image header information 5305 5306The second form (with "-d" option) is used to build a U-Boot image 5307from a "data file" which is used as image payload: 5308 5309 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5310 -n name -d data_file image 5311 -A ==> set architecture to 'arch' 5312 -O ==> set operating system to 'os' 5313 -T ==> set image type to 'type' 5314 -C ==> set compression type 'comp' 5315 -a ==> set load address to 'addr' (hex) 5316 -e ==> set entry point to 'ep' (hex) 5317 -n ==> set image name to 'name' 5318 -d ==> use image data from 'datafile' 5319 5320Right now, all Linux kernels for PowerPC systems use the same load 5321address (0x00000000), but the entry point address depends on the 5322kernel version: 5323 5324- 2.2.x kernels have the entry point at 0x0000000C, 5325- 2.3.x and later kernels have the entry point at 0x00000000. 5326 5327So a typical call to build a U-Boot image would read: 5328 5329 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5330 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5331 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5332 > examples/uImage.TQM850L 5333 Image Name: 2.4.4 kernel for TQM850L 5334 Created: Wed Jul 19 02:34:59 2000 5335 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5336 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5337 Load Address: 0x00000000 5338 Entry Point: 0x00000000 5339 5340To verify the contents of the image (or check for corruption): 5341 5342 -> tools/mkimage -l examples/uImage.TQM850L 5343 Image Name: 2.4.4 kernel for TQM850L 5344 Created: Wed Jul 19 02:34:59 2000 5345 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5346 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5347 Load Address: 0x00000000 5348 Entry Point: 0x00000000 5349 5350NOTE: for embedded systems where boot time is critical you can trade 5351speed for memory and install an UNCOMPRESSED image instead: this 5352needs more space in Flash, but boots much faster since it does not 5353need to be uncompressed: 5354 5355 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5356 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5357 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5358 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5359 > examples/uImage.TQM850L-uncompressed 5360 Image Name: 2.4.4 kernel for TQM850L 5361 Created: Wed Jul 19 02:34:59 2000 5362 Image Type: PowerPC Linux Kernel Image (uncompressed) 5363 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5364 Load Address: 0x00000000 5365 Entry Point: 0x00000000 5366 5367 5368Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5369when your kernel is intended to use an initial ramdisk: 5370 5371 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5372 > -A ppc -O linux -T ramdisk -C gzip \ 5373 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5374 Image Name: Simple Ramdisk Image 5375 Created: Wed Jan 12 14:01:50 2000 5376 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5377 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5378 Load Address: 0x00000000 5379 Entry Point: 0x00000000 5380 5381The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5382option performs the converse operation of the mkimage's second form (the "-d" 5383option). Given an image built by mkimage, the dumpimage extracts a "data file" 5384from the image: 5385 5386 tools/dumpimage -i image -p position data_file 5387 -i ==> extract from the 'image' a specific 'data_file', \ 5388 indexed by 'position' 5389 5390 5391Installing a Linux Image: 5392------------------------- 5393 5394To downloading a U-Boot image over the serial (console) interface, 5395you must convert the image to S-Record format: 5396 5397 objcopy -I binary -O srec examples/image examples/image.srec 5398 5399The 'objcopy' does not understand the information in the U-Boot 5400image header, so the resulting S-Record file will be relative to 5401address 0x00000000. To load it to a given address, you need to 5402specify the target address as 'offset' parameter with the 'loads' 5403command. 5404 5405Example: install the image to address 0x40100000 (which on the 5406TQM8xxL is in the first Flash bank): 5407 5408 => erase 40100000 401FFFFF 5409 5410 .......... done 5411 Erased 8 sectors 5412 5413 => loads 40100000 5414 ## Ready for S-Record download ... 5415 ~>examples/image.srec 5416 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5417 ... 5418 15989 15990 15991 15992 5419 [file transfer complete] 5420 [connected] 5421 ## Start Addr = 0x00000000 5422 5423 5424You can check the success of the download using the 'iminfo' command; 5425this includes a checksum verification so you can be sure no data 5426corruption happened: 5427 5428 => imi 40100000 5429 5430 ## Checking Image at 40100000 ... 5431 Image Name: 2.2.13 for initrd on TQM850L 5432 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5433 Data Size: 335725 Bytes = 327 kB = 0 MB 5434 Load Address: 00000000 5435 Entry Point: 0000000c 5436 Verifying Checksum ... OK 5437 5438 5439Boot Linux: 5440----------- 5441 5442The "bootm" command is used to boot an application that is stored in 5443memory (RAM or Flash). In case of a Linux kernel image, the contents 5444of the "bootargs" environment variable is passed to the kernel as 5445parameters. You can check and modify this variable using the 5446"printenv" and "setenv" commands: 5447 5448 5449 => printenv bootargs 5450 bootargs=root=/dev/ram 5451 5452 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5453 5454 => printenv bootargs 5455 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5456 5457 => bootm 40020000 5458 ## Booting Linux kernel at 40020000 ... 5459 Image Name: 2.2.13 for NFS on TQM850L 5460 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5461 Data Size: 381681 Bytes = 372 kB = 0 MB 5462 Load Address: 00000000 5463 Entry Point: 0000000c 5464 Verifying Checksum ... OK 5465 Uncompressing Kernel Image ... OK 5466 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 5467 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5468 time_init: decrementer frequency = 187500000/60 5469 Calibrating delay loop... 49.77 BogoMIPS 5470 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5471 ... 5472 5473If you want to boot a Linux kernel with initial RAM disk, you pass 5474the memory addresses of both the kernel and the initrd image (PPBCOOT 5475format!) to the "bootm" command: 5476 5477 => imi 40100000 40200000 5478 5479 ## Checking Image at 40100000 ... 5480 Image Name: 2.2.13 for initrd on TQM850L 5481 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5482 Data Size: 335725 Bytes = 327 kB = 0 MB 5483 Load Address: 00000000 5484 Entry Point: 0000000c 5485 Verifying Checksum ... OK 5486 5487 ## Checking Image at 40200000 ... 5488 Image Name: Simple Ramdisk Image 5489 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5490 Data Size: 566530 Bytes = 553 kB = 0 MB 5491 Load Address: 00000000 5492 Entry Point: 00000000 5493 Verifying Checksum ... OK 5494 5495 => bootm 40100000 40200000 5496 ## Booting Linux kernel at 40100000 ... 5497 Image Name: 2.2.13 for initrd on TQM850L 5498 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5499 Data Size: 335725 Bytes = 327 kB = 0 MB 5500 Load Address: 00000000 5501 Entry Point: 0000000c 5502 Verifying Checksum ... OK 5503 Uncompressing Kernel Image ... OK 5504 ## Loading RAMDisk Image at 40200000 ... 5505 Image Name: Simple Ramdisk Image 5506 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5507 Data Size: 566530 Bytes = 553 kB = 0 MB 5508 Load Address: 00000000 5509 Entry Point: 00000000 5510 Verifying Checksum ... OK 5511 Loading Ramdisk ... OK 5512 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 5513 Boot arguments: root=/dev/ram 5514 time_init: decrementer frequency = 187500000/60 5515 Calibrating delay loop... 49.77 BogoMIPS 5516 ... 5517 RAMDISK: Compressed image found at block 0 5518 VFS: Mounted root (ext2 filesystem). 5519 5520 bash# 5521 5522Boot Linux and pass a flat device tree: 5523----------- 5524 5525First, U-Boot must be compiled with the appropriate defines. See the section 5526titled "Linux Kernel Interface" above for a more in depth explanation. The 5527following is an example of how to start a kernel and pass an updated 5528flat device tree: 5529 5530=> print oftaddr 5531oftaddr=0x300000 5532=> print oft 5533oft=oftrees/mpc8540ads.dtb 5534=> tftp $oftaddr $oft 5535Speed: 1000, full duplex 5536Using TSEC0 device 5537TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5538Filename 'oftrees/mpc8540ads.dtb'. 5539Load address: 0x300000 5540Loading: # 5541done 5542Bytes transferred = 4106 (100a hex) 5543=> tftp $loadaddr $bootfile 5544Speed: 1000, full duplex 5545Using TSEC0 device 5546TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5547Filename 'uImage'. 5548Load address: 0x200000 5549Loading:############ 5550done 5551Bytes transferred = 1029407 (fb51f hex) 5552=> print loadaddr 5553loadaddr=200000 5554=> print oftaddr 5555oftaddr=0x300000 5556=> bootm $loadaddr - $oftaddr 5557## Booting image at 00200000 ... 5558 Image Name: Linux-2.6.17-dirty 5559 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5560 Data Size: 1029343 Bytes = 1005.2 kB 5561 Load Address: 00000000 5562 Entry Point: 00000000 5563 Verifying Checksum ... OK 5564 Uncompressing Kernel Image ... OK 5565Booting using flat device tree at 0x300000 5566Using MPC85xx ADS machine description 5567Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5568[snip] 5569 5570 5571More About U-Boot Image Types: 5572------------------------------ 5573 5574U-Boot supports the following image types: 5575 5576 "Standalone Programs" are directly runnable in the environment 5577 provided by U-Boot; it is expected that (if they behave 5578 well) you can continue to work in U-Boot after return from 5579 the Standalone Program. 5580 "OS Kernel Images" are usually images of some Embedded OS which 5581 will take over control completely. Usually these programs 5582 will install their own set of exception handlers, device 5583 drivers, set up the MMU, etc. - this means, that you cannot 5584 expect to re-enter U-Boot except by resetting the CPU. 5585 "RAMDisk Images" are more or less just data blocks, and their 5586 parameters (address, size) are passed to an OS kernel that is 5587 being started. 5588 "Multi-File Images" contain several images, typically an OS 5589 (Linux) kernel image and one or more data images like 5590 RAMDisks. This construct is useful for instance when you want 5591 to boot over the network using BOOTP etc., where the boot 5592 server provides just a single image file, but you want to get 5593 for instance an OS kernel and a RAMDisk image. 5594 5595 "Multi-File Images" start with a list of image sizes, each 5596 image size (in bytes) specified by an "uint32_t" in network 5597 byte order. This list is terminated by an "(uint32_t)0". 5598 Immediately after the terminating 0 follow the images, one by 5599 one, all aligned on "uint32_t" boundaries (size rounded up to 5600 a multiple of 4 bytes). 5601 5602 "Firmware Images" are binary images containing firmware (like 5603 U-Boot or FPGA images) which usually will be programmed to 5604 flash memory. 5605 5606 "Script files" are command sequences that will be executed by 5607 U-Boot's command interpreter; this feature is especially 5608 useful when you configure U-Boot to use a real shell (hush) 5609 as command interpreter. 5610 5611Booting the Linux zImage: 5612------------------------- 5613 5614On some platforms, it's possible to boot Linux zImage. This is done 5615using the "bootz" command. The syntax of "bootz" command is the same 5616as the syntax of "bootm" command. 5617 5618Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5619kernel with raw initrd images. The syntax is slightly different, the 5620address of the initrd must be augmented by it's size, in the following 5621format: "<initrd addres>:<initrd size>". 5622 5623 5624Standalone HOWTO: 5625================= 5626 5627One of the features of U-Boot is that you can dynamically load and 5628run "standalone" applications, which can use some resources of 5629U-Boot like console I/O functions or interrupt services. 5630 5631Two simple examples are included with the sources: 5632 5633"Hello World" Demo: 5634------------------- 5635 5636'examples/hello_world.c' contains a small "Hello World" Demo 5637application; it is automatically compiled when you build U-Boot. 5638It's configured to run at address 0x00040004, so you can play with it 5639like that: 5640 5641 => loads 5642 ## Ready for S-Record download ... 5643 ~>examples/hello_world.srec 5644 1 2 3 4 5 6 7 8 9 10 11 ... 5645 [file transfer complete] 5646 [connected] 5647 ## Start Addr = 0x00040004 5648 5649 => go 40004 Hello World! This is a test. 5650 ## Starting application at 0x00040004 ... 5651 Hello World 5652 argc = 7 5653 argv[0] = "40004" 5654 argv[1] = "Hello" 5655 argv[2] = "World!" 5656 argv[3] = "This" 5657 argv[4] = "is" 5658 argv[5] = "a" 5659 argv[6] = "test." 5660 argv[7] = "<NULL>" 5661 Hit any key to exit ... 5662 5663 ## Application terminated, rc = 0x0 5664 5665Another example, which demonstrates how to register a CPM interrupt 5666handler with the U-Boot code, can be found in 'examples/timer.c'. 5667Here, a CPM timer is set up to generate an interrupt every second. 5668The interrupt service routine is trivial, just printing a '.' 5669character, but this is just a demo program. The application can be 5670controlled by the following keys: 5671 5672 ? - print current values og the CPM Timer registers 5673 b - enable interrupts and start timer 5674 e - stop timer and disable interrupts 5675 q - quit application 5676 5677 => loads 5678 ## Ready for S-Record download ... 5679 ~>examples/timer.srec 5680 1 2 3 4 5 6 7 8 9 10 11 ... 5681 [file transfer complete] 5682 [connected] 5683 ## Start Addr = 0x00040004 5684 5685 => go 40004 5686 ## Starting application at 0x00040004 ... 5687 TIMERS=0xfff00980 5688 Using timer 1 5689 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5690 5691Hit 'b': 5692 [q, b, e, ?] Set interval 1000000 us 5693 Enabling timer 5694Hit '?': 5695 [q, b, e, ?] ........ 5696 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5697Hit '?': 5698 [q, b, e, ?] . 5699 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5700Hit '?': 5701 [q, b, e, ?] . 5702 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5703Hit '?': 5704 [q, b, e, ?] . 5705 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5706Hit 'e': 5707 [q, b, e, ?] ...Stopping timer 5708Hit 'q': 5709 [q, b, e, ?] ## Application terminated, rc = 0x0 5710 5711 5712Minicom warning: 5713================ 5714 5715Over time, many people have reported problems when trying to use the 5716"minicom" terminal emulation program for serial download. I (wd) 5717consider minicom to be broken, and recommend not to use it. Under 5718Unix, I recommend to use C-Kermit for general purpose use (and 5719especially for kermit binary protocol download ("loadb" command), and 5720use "cu" for S-Record download ("loads" command). See 5721http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5722for help with kermit. 5723 5724 5725Nevertheless, if you absolutely want to use it try adding this 5726configuration to your "File transfer protocols" section: 5727 5728 Name Program Name U/D FullScr IO-Red. Multi 5729 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5730 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5731 5732 5733NetBSD Notes: 5734============= 5735 5736Starting at version 0.9.2, U-Boot supports NetBSD both as host 5737(build U-Boot) and target system (boots NetBSD/mpc8xx). 5738 5739Building requires a cross environment; it is known to work on 5740NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5741need gmake since the Makefiles are not compatible with BSD make). 5742Note that the cross-powerpc package does not install include files; 5743attempting to build U-Boot will fail because <machine/ansi.h> is 5744missing. This file has to be installed and patched manually: 5745 5746 # cd /usr/pkg/cross/powerpc-netbsd/include 5747 # mkdir powerpc 5748 # ln -s powerpc machine 5749 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5750 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5751 5752Native builds *don't* work due to incompatibilities between native 5753and U-Boot include files. 5754 5755Booting assumes that (the first part of) the image booted is a 5756stage-2 loader which in turn loads and then invokes the kernel 5757proper. Loader sources will eventually appear in the NetBSD source 5758tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5759meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5760 5761 5762Implementation Internals: 5763========================= 5764 5765The following is not intended to be a complete description of every 5766implementation detail. However, it should help to understand the 5767inner workings of U-Boot and make it easier to port it to custom 5768hardware. 5769 5770 5771Initial Stack, Global Data: 5772--------------------------- 5773 5774The implementation of U-Boot is complicated by the fact that U-Boot 5775starts running out of ROM (flash memory), usually without access to 5776system RAM (because the memory controller is not initialized yet). 5777This means that we don't have writable Data or BSS segments, and BSS 5778is not initialized as zero. To be able to get a C environment working 5779at all, we have to allocate at least a minimal stack. Implementation 5780options for this are defined and restricted by the CPU used: Some CPU 5781models provide on-chip memory (like the IMMR area on MPC8xx and 5782MPC826x processors), on others (parts of) the data cache can be 5783locked as (mis-) used as memory, etc. 5784 5785 Chris Hallinan posted a good summary of these issues to the 5786 U-Boot mailing list: 5787 5788 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5789 From: "Chris Hallinan" <clh@net1plus.com> 5790 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5791 ... 5792 5793 Correct me if I'm wrong, folks, but the way I understand it 5794 is this: Using DCACHE as initial RAM for Stack, etc, does not 5795 require any physical RAM backing up the cache. The cleverness 5796 is that the cache is being used as a temporary supply of 5797 necessary storage before the SDRAM controller is setup. It's 5798 beyond the scope of this list to explain the details, but you 5799 can see how this works by studying the cache architecture and 5800 operation in the architecture and processor-specific manuals. 5801 5802 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5803 is another option for the system designer to use as an 5804 initial stack/RAM area prior to SDRAM being available. Either 5805 option should work for you. Using CS 4 should be fine if your 5806 board designers haven't used it for something that would 5807 cause you grief during the initial boot! It is frequently not 5808 used. 5809 5810 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5811 with your processor/board/system design. The default value 5812 you will find in any recent u-boot distribution in 5813 walnut.h should work for you. I'd set it to a value larger 5814 than your SDRAM module. If you have a 64MB SDRAM module, set 5815 it above 400_0000. Just make sure your board has no resources 5816 that are supposed to respond to that address! That code in 5817 start.S has been around a while and should work as is when 5818 you get the config right. 5819 5820 -Chris Hallinan 5821 DS4.COM, Inc. 5822 5823It is essential to remember this, since it has some impact on the C 5824code for the initialization procedures: 5825 5826* Initialized global data (data segment) is read-only. Do not attempt 5827 to write it. 5828 5829* Do not use any uninitialized global data (or implicitely initialized 5830 as zero data - BSS segment) at all - this is undefined, initiali- 5831 zation is performed later (when relocating to RAM). 5832 5833* Stack space is very limited. Avoid big data buffers or things like 5834 that. 5835 5836Having only the stack as writable memory limits means we cannot use 5837normal global data to share information beween the code. But it 5838turned out that the implementation of U-Boot can be greatly 5839simplified by making a global data structure (gd_t) available to all 5840functions. We could pass a pointer to this data as argument to _all_ 5841functions, but this would bloat the code. Instead we use a feature of 5842the GCC compiler (Global Register Variables) to share the data: we 5843place a pointer (gd) to the global data into a register which we 5844reserve for this purpose. 5845 5846When choosing a register for such a purpose we are restricted by the 5847relevant (E)ABI specifications for the current architecture, and by 5848GCC's implementation. 5849 5850For PowerPC, the following registers have specific use: 5851 R1: stack pointer 5852 R2: reserved for system use 5853 R3-R4: parameter passing and return values 5854 R5-R10: parameter passing 5855 R13: small data area pointer 5856 R30: GOT pointer 5857 R31: frame pointer 5858 5859 (U-Boot also uses R12 as internal GOT pointer. r12 5860 is a volatile register so r12 needs to be reset when 5861 going back and forth between asm and C) 5862 5863 ==> U-Boot will use R2 to hold a pointer to the global data 5864 5865 Note: on PPC, we could use a static initializer (since the 5866 address of the global data structure is known at compile time), 5867 but it turned out that reserving a register results in somewhat 5868 smaller code - although the code savings are not that big (on 5869 average for all boards 752 bytes for the whole U-Boot image, 5870 624 text + 127 data). 5871 5872On Blackfin, the normal C ABI (except for P3) is followed as documented here: 5873 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 5874 5875 ==> U-Boot will use P3 to hold a pointer to the global data 5876 5877On ARM, the following registers are used: 5878 5879 R0: function argument word/integer result 5880 R1-R3: function argument word 5881 R9: platform specific 5882 R10: stack limit (used only if stack checking is enabled) 5883 R11: argument (frame) pointer 5884 R12: temporary workspace 5885 R13: stack pointer 5886 R14: link register 5887 R15: program counter 5888 5889 ==> U-Boot will use R9 to hold a pointer to the global data 5890 5891 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5892 5893On Nios II, the ABI is documented here: 5894 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5895 5896 ==> U-Boot will use gp to hold a pointer to the global data 5897 5898 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5899 to access small data sections, so gp is free. 5900 5901On NDS32, the following registers are used: 5902 5903 R0-R1: argument/return 5904 R2-R5: argument 5905 R15: temporary register for assembler 5906 R16: trampoline register 5907 R28: frame pointer (FP) 5908 R29: global pointer (GP) 5909 R30: link register (LP) 5910 R31: stack pointer (SP) 5911 PC: program counter (PC) 5912 5913 ==> U-Boot will use R10 to hold a pointer to the global data 5914 5915NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5916or current versions of GCC may "optimize" the code too much. 5917 5918Memory Management: 5919------------------ 5920 5921U-Boot runs in system state and uses physical addresses, i.e. the 5922MMU is not used either for address mapping nor for memory protection. 5923 5924The available memory is mapped to fixed addresses using the memory 5925controller. In this process, a contiguous block is formed for each 5926memory type (Flash, SDRAM, SRAM), even when it consists of several 5927physical memory banks. 5928 5929U-Boot is installed in the first 128 kB of the first Flash bank (on 5930TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5931booting and sizing and initializing DRAM, the code relocates itself 5932to the upper end of DRAM. Immediately below the U-Boot code some 5933memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5934configuration setting]. Below that, a structure with global Board 5935Info data is placed, followed by the stack (growing downward). 5936 5937Additionally, some exception handler code is copied to the low 8 kB 5938of DRAM (0x00000000 ... 0x00001FFF). 5939 5940So a typical memory configuration with 16 MB of DRAM could look like 5941this: 5942 5943 0x0000 0000 Exception Vector code 5944 : 5945 0x0000 1FFF 5946 0x0000 2000 Free for Application Use 5947 : 5948 : 5949 5950 : 5951 : 5952 0x00FB FF20 Monitor Stack (Growing downward) 5953 0x00FB FFAC Board Info Data and permanent copy of global data 5954 0x00FC 0000 Malloc Arena 5955 : 5956 0x00FD FFFF 5957 0x00FE 0000 RAM Copy of Monitor Code 5958 ... eventually: LCD or video framebuffer 5959 ... eventually: pRAM (Protected RAM - unchanged by reset) 5960 0x00FF FFFF [End of RAM] 5961 5962 5963System Initialization: 5964---------------------- 5965 5966In the reset configuration, U-Boot starts at the reset entry point 5967(on most PowerPC systems at address 0x00000100). Because of the reset 5968configuration for CS0# this is a mirror of the onboard Flash memory. 5969To be able to re-map memory U-Boot then jumps to its link address. 5970To be able to implement the initialization code in C, a (small!) 5971initial stack is set up in the internal Dual Ported RAM (in case CPUs 5972which provide such a feature like MPC8xx or MPC8260), or in a locked 5973part of the data cache. After that, U-Boot initializes the CPU core, 5974the caches and the SIU. 5975 5976Next, all (potentially) available memory banks are mapped using a 5977preliminary mapping. For example, we put them on 512 MB boundaries 5978(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5979on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5980programmed for SDRAM access. Using the temporary configuration, a 5981simple memory test is run that determines the size of the SDRAM 5982banks. 5983 5984When there is more than one SDRAM bank, and the banks are of 5985different size, the largest is mapped first. For equal size, the first 5986bank (CS2#) is mapped first. The first mapping is always for address 59870x00000000, with any additional banks following immediately to create 5988contiguous memory starting from 0. 5989 5990Then, the monitor installs itself at the upper end of the SDRAM area 5991and allocates memory for use by malloc() and for the global Board 5992Info data; also, the exception vector code is copied to the low RAM 5993pages, and the final stack is set up. 5994 5995Only after this relocation will you have a "normal" C environment; 5996until that you are restricted in several ways, mostly because you are 5997running from ROM, and because the code will have to be relocated to a 5998new address in RAM. 5999 6000 6001U-Boot Porting Guide: 6002---------------------- 6003 6004[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 6005list, October 2002] 6006 6007 6008int main(int argc, char *argv[]) 6009{ 6010 sighandler_t no_more_time; 6011 6012 signal(SIGALRM, no_more_time); 6013 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 6014 6015 if (available_money > available_manpower) { 6016 Pay consultant to port U-Boot; 6017 return 0; 6018 } 6019 6020 Download latest U-Boot source; 6021 6022 Subscribe to u-boot mailing list; 6023 6024 if (clueless) 6025 email("Hi, I am new to U-Boot, how do I get started?"); 6026 6027 while (learning) { 6028 Read the README file in the top level directory; 6029 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 6030 Read applicable doc/*.README; 6031 Read the source, Luke; 6032 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 6033 } 6034 6035 if (available_money > toLocalCurrency ($2500)) 6036 Buy a BDI3000; 6037 else 6038 Add a lot of aggravation and time; 6039 6040 if (a similar board exists) { /* hopefully... */ 6041 cp -a board/<similar> board/<myboard> 6042 cp include/configs/<similar>.h include/configs/<myboard>.h 6043 } else { 6044 Create your own board support subdirectory; 6045 Create your own board include/configs/<myboard>.h file; 6046 } 6047 Edit new board/<myboard> files 6048 Edit new include/configs/<myboard>.h 6049 6050 while (!accepted) { 6051 while (!running) { 6052 do { 6053 Add / modify source code; 6054 } until (compiles); 6055 Debug; 6056 if (clueless) 6057 email("Hi, I am having problems..."); 6058 } 6059 Send patch file to the U-Boot email list; 6060 if (reasonable critiques) 6061 Incorporate improvements from email list code review; 6062 else 6063 Defend code as written; 6064 } 6065 6066 return 0; 6067} 6068 6069void no_more_time (int sig) 6070{ 6071 hire_a_guru(); 6072} 6073 6074 6075Coding Standards: 6076----------------- 6077 6078All contributions to U-Boot should conform to the Linux kernel 6079coding style; see the file "Documentation/CodingStyle" and the script 6080"scripts/Lindent" in your Linux kernel source directory. 6081 6082Source files originating from a different project (for example the 6083MTD subsystem) are generally exempt from these guidelines and are not 6084reformated to ease subsequent migration to newer versions of those 6085sources. 6086 6087Please note that U-Boot is implemented in C (and to some small parts in 6088Assembler); no C++ is used, so please do not use C++ style comments (//) 6089in your code. 6090 6091Please also stick to the following formatting rules: 6092- remove any trailing white space 6093- use TAB characters for indentation and vertical alignment, not spaces 6094- make sure NOT to use DOS '\r\n' line feeds 6095- do not add more than 2 consecutive empty lines to source files 6096- do not add trailing empty lines to source files 6097 6098Submissions which do not conform to the standards may be returned 6099with a request to reformat the changes. 6100 6101 6102Submitting Patches: 6103------------------- 6104 6105Since the number of patches for U-Boot is growing, we need to 6106establish some rules. Submissions which do not conform to these rules 6107may be rejected, even when they contain important and valuable stuff. 6108 6109Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6110 6111Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6112see http://lists.denx.de/mailman/listinfo/u-boot 6113 6114When you send a patch, please include the following information with 6115it: 6116 6117* For bug fixes: a description of the bug and how your patch fixes 6118 this bug. Please try to include a way of demonstrating that the 6119 patch actually fixes something. 6120 6121* For new features: a description of the feature and your 6122 implementation. 6123 6124* A CHANGELOG entry as plaintext (separate from the patch) 6125 6126* For major contributions, your entry to the CREDITS file 6127 6128* When you add support for a new board, don't forget to add a 6129 maintainer e-mail address to the boards.cfg file, too. 6130 6131* If your patch adds new configuration options, don't forget to 6132 document these in the README file. 6133 6134* The patch itself. If you are using git (which is *strongly* 6135 recommended) you can easily generate the patch using the 6136 "git format-patch". If you then use "git send-email" to send it to 6137 the U-Boot mailing list, you will avoid most of the common problems 6138 with some other mail clients. 6139 6140 If you cannot use git, use "diff -purN OLD NEW". If your version of 6141 diff does not support these options, then get the latest version of 6142 GNU diff. 6143 6144 The current directory when running this command shall be the parent 6145 directory of the U-Boot source tree (i. e. please make sure that 6146 your patch includes sufficient directory information for the 6147 affected files). 6148 6149 We prefer patches as plain text. MIME attachments are discouraged, 6150 and compressed attachments must not be used. 6151 6152* If one logical set of modifications affects or creates several 6153 files, all these changes shall be submitted in a SINGLE patch file. 6154 6155* Changesets that contain different, unrelated modifications shall be 6156 submitted as SEPARATE patches, one patch per changeset. 6157 6158 6159Notes: 6160 6161* Before sending the patch, run the MAKEALL script on your patched 6162 source tree and make sure that no errors or warnings are reported 6163 for any of the boards. 6164 6165* Keep your modifications to the necessary minimum: A patch 6166 containing several unrelated changes or arbitrary reformats will be 6167 returned with a request to re-formatting / split it. 6168 6169* If you modify existing code, make sure that your new code does not 6170 add to the memory footprint of the code ;-) Small is beautiful! 6171 When adding new features, these should compile conditionally only 6172 (using #ifdef), and the resulting code with the new feature 6173 disabled must not need more memory than the old code without your 6174 modification. 6175 6176* Remember that there is a size limit of 100 kB per message on the 6177 u-boot mailing list. Bigger patches will be moderated. If they are 6178 reasonable and not too big, they will be acknowledged. But patches 6179 bigger than the size limit should be avoided. 6180