1# 2# (C) Copyright 2000 - 2012 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 8# This program is free software; you can redistribute it and/or 9# modify it under the terms of the GNU General Public License as 10# published by the Free Software Foundation; either version 2 of 11# the License, or (at your option) any later version. 12# 13# This program is distributed in the hope that it will be useful, 14# but WITHOUT ANY WARRANTY; without even the implied warranty of 15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16# GNU General Public License for more details. 17# 18# You should have received a copy of the GNU General Public License 19# along with this program; if not, write to the Free Software 20# Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21# MA 02111-1307 USA 22# 23 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC, ARM, MIPS and several other 29processors, which can be installed in a boot ROM and used to 30initialize and test the hardware or to download and run application 31code. 32 33The development of U-Boot is closely related to Linux: some parts of 34the source code originate in the Linux source tree, we have some 35header files in common, and special provision has been made to 36support booting of Linux images. 37 38Some attention has been paid to make this software easily 39configurable and extendable. For instance, all monitor commands are 40implemented with the same call interface, so that it's very easy to 41add new commands. Also, instead of permanently adding rarely used 42code (for instance hardware test utilities) to the monitor, you can 43load and run it dynamically. 44 45 46Status: 47======= 48 49In general, all boards for which a configuration option exists in the 50Makefile have been tested to some extent and can be considered 51"working". In fact, many of them are used in production systems. 52 53In case of problems see the CHANGELOG and CREDITS files to find out 54who contributed the specific port. The MAINTAINERS file lists board 55maintainers. 56 57Note: There is no CHANGELOG file in the actual U-Boot source tree; 58it can be created dynamically from the Git log using: 59 60 make CHANGELOG 61 62 63Where to get help: 64================== 65 66In case you have questions about, problems with or contributions for 67U-Boot you should send a message to the U-Boot mailing list at 68<u-boot@lists.denx.de>. There is also an archive of previous traffic 69on the mailing list - please search the archive before asking FAQ's. 70Please see http://lists.denx.de/pipermail/u-boot and 71http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 72 73 74Where to get source code: 75========================= 76 77The U-Boot source code is maintained in the git repository at 78git://www.denx.de/git/u-boot.git ; you can browse it online at 79http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 80 81The "snapshot" links on this page allow you to download tarballs of 82any version you might be interested in. Official releases are also 83available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 84directory. 85 86Pre-built (and tested) images are available from 87ftp://ftp.denx.de/pub/u-boot/images/ 88 89 90Where we come from: 91=================== 92 93- start from 8xxrom sources 94- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 95- clean up code 96- make it easier to add custom boards 97- make it possible to add other [PowerPC] CPUs 98- extend functions, especially: 99 * Provide extended interface to Linux boot loader 100 * S-Record download 101 * network boot 102 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 103- create ARMBoot project (http://sourceforge.net/projects/armboot) 104- add other CPU families (starting with ARM) 105- create U-Boot project (http://sourceforge.net/projects/u-boot) 106- current project page: see http://www.denx.de/wiki/U-Boot 107 108 109Names and Spelling: 110=================== 111 112The "official" name of this project is "Das U-Boot". The spelling 113"U-Boot" shall be used in all written text (documentation, comments 114in source files etc.). Example: 115 116 This is the README file for the U-Boot project. 117 118File names etc. shall be based on the string "u-boot". Examples: 119 120 include/asm-ppc/u-boot.h 121 122 #include <asm/u-boot.h> 123 124Variable names, preprocessor constants etc. shall be either based on 125the string "u_boot" or on "U_BOOT". Example: 126 127 U_BOOT_VERSION u_boot_logo 128 IH_OS_U_BOOT u_boot_hush_start 129 130 131Versioning: 132=========== 133 134Starting with the release in October 2008, the names of the releases 135were changed from numerical release numbers without deeper meaning 136into a time stamp based numbering. Regular releases are identified by 137names consisting of the calendar year and month of the release date. 138Additional fields (if present) indicate release candidates or bug fix 139releases in "stable" maintenance trees. 140 141Examples: 142 U-Boot v2009.11 - Release November 2009 143 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 144 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 145 146 147Directory Hierarchy: 148==================== 149 150/arch Architecture specific files 151 /arm Files generic to ARM architecture 152 /cpu CPU specific files 153 /arm720t Files specific to ARM 720 CPUs 154 /arm920t Files specific to ARM 920 CPUs 155 /at91 Files specific to Atmel AT91RM9200 CPU 156 /imx Files specific to Freescale MC9328 i.MX CPUs 157 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 158 /arm925t Files specific to ARM 925 CPUs 159 /arm926ejs Files specific to ARM 926 CPUs 160 /arm1136 Files specific to ARM 1136 CPUs 161 /ixp Files specific to Intel XScale IXP CPUs 162 /pxa Files specific to Intel XScale PXA CPUs 163 /s3c44b0 Files specific to Samsung S3C44B0 CPUs 164 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 165 /lib Architecture specific library files 166 /avr32 Files generic to AVR32 architecture 167 /cpu CPU specific files 168 /lib Architecture specific library files 169 /blackfin Files generic to Analog Devices Blackfin architecture 170 /cpu CPU specific files 171 /lib Architecture specific library files 172 /x86 Files generic to x86 architecture 173 /cpu CPU specific files 174 /lib Architecture specific library files 175 /m68k Files generic to m68k architecture 176 /cpu CPU specific files 177 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 178 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 179 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 180 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 181 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 182 /lib Architecture specific library files 183 /microblaze Files generic to microblaze architecture 184 /cpu CPU specific files 185 /lib Architecture specific library files 186 /mips Files generic to MIPS architecture 187 /cpu CPU specific files 188 /mips32 Files specific to MIPS32 CPUs 189 /xburst Files specific to Ingenic XBurst CPUs 190 /lib Architecture specific library files 191 /nds32 Files generic to NDS32 architecture 192 /cpu CPU specific files 193 /n1213 Files specific to Andes Technology N1213 CPUs 194 /lib Architecture specific library files 195 /nios2 Files generic to Altera NIOS2 architecture 196 /cpu CPU specific files 197 /lib Architecture specific library files 198 /powerpc Files generic to PowerPC architecture 199 /cpu CPU specific files 200 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 201 /mpc5xx Files specific to Freescale MPC5xx CPUs 202 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 203 /mpc8xx Files specific to Freescale MPC8xx CPUs 204 /mpc8220 Files specific to Freescale MPC8220 CPUs 205 /mpc824x Files specific to Freescale MPC824x CPUs 206 /mpc8260 Files specific to Freescale MPC8260 CPUs 207 /mpc85xx Files specific to Freescale MPC85xx CPUs 208 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 209 /lib Architecture specific library files 210 /sh Files generic to SH architecture 211 /cpu CPU specific files 212 /sh2 Files specific to sh2 CPUs 213 /sh3 Files specific to sh3 CPUs 214 /sh4 Files specific to sh4 CPUs 215 /lib Architecture specific library files 216 /sparc Files generic to SPARC architecture 217 /cpu CPU specific files 218 /leon2 Files specific to Gaisler LEON2 SPARC CPU 219 /leon3 Files specific to Gaisler LEON3 SPARC CPU 220 /lib Architecture specific library files 221/api Machine/arch independent API for external apps 222/board Board dependent files 223/common Misc architecture independent functions 224/disk Code for disk drive partition handling 225/doc Documentation (don't expect too much) 226/drivers Commonly used device drivers 227/examples Example code for standalone applications, etc. 228/fs Filesystem code (cramfs, ext2, jffs2, etc.) 229/include Header Files 230/lib Files generic to all architectures 231 /libfdt Library files to support flattened device trees 232 /lzma Library files to support LZMA decompression 233 /lzo Library files to support LZO decompression 234/net Networking code 235/post Power On Self Test 236/rtc Real Time Clock drivers 237/tools Tools to build S-Record or U-Boot images, etc. 238 239Software Configuration: 240======================= 241 242Configuration is usually done using C preprocessor defines; the 243rationale behind that is to avoid dead code whenever possible. 244 245There are two classes of configuration variables: 246 247* Configuration _OPTIONS_: 248 These are selectable by the user and have names beginning with 249 "CONFIG_". 250 251* Configuration _SETTINGS_: 252 These depend on the hardware etc. and should not be meddled with if 253 you don't know what you're doing; they have names beginning with 254 "CONFIG_SYS_". 255 256Later we will add a configuration tool - probably similar to or even 257identical to what's used for the Linux kernel. Right now, we have to 258do the configuration by hand, which means creating some symbolic 259links and editing some configuration files. We use the TQM8xxL boards 260as an example here. 261 262 263Selection of Processor Architecture and Board Type: 264--------------------------------------------------- 265 266For all supported boards there are ready-to-use default 267configurations available; just type "make <board_name>_config". 268 269Example: For a TQM823L module type: 270 271 cd u-boot 272 make TQM823L_config 273 274For the Cogent platform, you need to specify the CPU type as well; 275e.g. "make cogent_mpc8xx_config". And also configure the cogent 276directory according to the instructions in cogent/README. 277 278 279Configuration Options: 280---------------------- 281 282Configuration depends on the combination of board and CPU type; all 283such information is kept in a configuration file 284"include/configs/<board_name>.h". 285 286Example: For a TQM823L module, all configuration settings are in 287"include/configs/TQM823L.h". 288 289 290Many of the options are named exactly as the corresponding Linux 291kernel configuration options. The intention is to make it easier to 292build a config tool - later. 293 294 295The following options need to be configured: 296 297- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 298 299- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 300 301- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 302 Define exactly one, e.g. CONFIG_ATSTK1002 303 304- CPU Module Type: (if CONFIG_COGENT is defined) 305 Define exactly one of 306 CONFIG_CMA286_60_OLD 307--- FIXME --- not tested yet: 308 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 309 CONFIG_CMA287_23, CONFIG_CMA287_50 310 311- Motherboard Type: (if CONFIG_COGENT is defined) 312 Define exactly one of 313 CONFIG_CMA101, CONFIG_CMA102 314 315- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 316 Define one or more of 317 CONFIG_CMA302 318 319- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 320 Define one or more of 321 CONFIG_LCD_HEARTBEAT - update a character position on 322 the LCD display every second with 323 a "rotator" |\-/|\-/ 324 325- Board flavour: (if CONFIG_MPC8260ADS is defined) 326 CONFIG_ADSTYPE 327 Possible values are: 328 CONFIG_SYS_8260ADS - original MPC8260ADS 329 CONFIG_SYS_8266ADS - MPC8266ADS 330 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 331 CONFIG_SYS_8272ADS - MPC8272ADS 332 333- Marvell Family Member 334 CONFIG_SYS_MVFS - define it if you want to enable 335 multiple fs option at one time 336 for marvell soc family 337 338- MPC824X Family Member (if CONFIG_MPC824X is defined) 339 Define exactly one of 340 CONFIG_MPC8240, CONFIG_MPC8245 341 342- 8xx CPU Options: (if using an MPC8xx CPU) 343 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 344 get_gclk_freq() cannot work 345 e.g. if there is no 32KHz 346 reference PIT/RTC clock 347 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 348 or XTAL/EXTAL) 349 350- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 351 CONFIG_SYS_8xx_CPUCLK_MIN 352 CONFIG_SYS_8xx_CPUCLK_MAX 353 CONFIG_8xx_CPUCLK_DEFAULT 354 See doc/README.MPC866 355 356 CONFIG_SYS_MEASURE_CPUCLK 357 358 Define this to measure the actual CPU clock instead 359 of relying on the correctness of the configured 360 values. Mostly useful for board bringup to make sure 361 the PLL is locked at the intended frequency. Note 362 that this requires a (stable) reference clock (32 kHz 363 RTC clock or CONFIG_SYS_8XX_XIN) 364 365 CONFIG_SYS_DELAYED_ICACHE 366 367 Define this option if you want to enable the 368 ICache only when Code runs from RAM. 369 370- 85xx CPU Options: 371 CONFIG_SYS_PPC64 372 373 Specifies that the core is a 64-bit PowerPC implementation (implements 374 the "64" category of the Power ISA). This is necessary for ePAPR 375 compliance, among other possible reasons. 376 377 CONFIG_SYS_FSL_TBCLK_DIV 378 379 Defines the core time base clock divider ratio compared to the 380 system clock. On most PQ3 devices this is 8, on newer QorIQ 381 devices it can be 16 or 32. The ratio varies from SoC to Soc. 382 383 CONFIG_SYS_FSL_PCIE_COMPAT 384 385 Defines the string to utilize when trying to match PCIe device 386 tree nodes for the given platform. 387 388 CONFIG_SYS_PPC_E500_DEBUG_TLB 389 390 Enables a temporary TLB entry to be used during boot to work 391 around limitations in e500v1 and e500v2 external debugger 392 support. This reduces the portions of the boot code where 393 breakpoints and single stepping do not work. The value of this 394 symbol should be set to the TLB1 entry to be used for this 395 purpose. 396 397 CONFIG_SYS_FSL_ERRATUM_A004510 398 399 Enables a workaround for erratum A004510. If set, 400 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 401 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 402 403 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 404 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 405 406 Defines one or two SoC revisions (low 8 bits of SVR) 407 for which the A004510 workaround should be applied. 408 409 The rest of SVR is either not relevant to the decision 410 of whether the erratum is present (e.g. p2040 versus 411 p2041) or is implied by the build target, which controls 412 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 413 414 See Freescale App Note 4493 for more information about 415 this erratum. 416 417 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 418 419 This is the value to write into CCSR offset 0x18600 420 according to the A004510 workaround. 421 422- Generic CPU options: 423 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 424 425 Defines the endianess of the CPU. Implementation of those 426 values is arch specific. 427 428- Intel Monahans options: 429 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 430 431 Defines the Monahans run mode to oscillator 432 ratio. Valid values are 8, 16, 24, 31. The core 433 frequency is this value multiplied by 13 MHz. 434 435 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 436 437 Defines the Monahans turbo mode to oscillator 438 ratio. Valid values are 1 (default if undefined) and 439 2. The core frequency as calculated above is multiplied 440 by this value. 441 442- MIPS CPU options: 443 CONFIG_SYS_INIT_SP_OFFSET 444 445 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 446 pointer. This is needed for the temporary stack before 447 relocation. 448 449 CONFIG_SYS_MIPS_CACHE_MODE 450 451 Cache operation mode for the MIPS CPU. 452 See also arch/mips/include/asm/mipsregs.h. 453 Possible values are: 454 CONF_CM_CACHABLE_NO_WA 455 CONF_CM_CACHABLE_WA 456 CONF_CM_UNCACHED 457 CONF_CM_CACHABLE_NONCOHERENT 458 CONF_CM_CACHABLE_CE 459 CONF_CM_CACHABLE_COW 460 CONF_CM_CACHABLE_CUW 461 CONF_CM_CACHABLE_ACCELERATED 462 463 CONFIG_SYS_XWAY_EBU_BOOTCFG 464 465 Special option for Lantiq XWAY SoCs for booting from NOR flash. 466 See also arch/mips/cpu/mips32/start.S. 467 468 CONFIG_XWAY_SWAP_BYTES 469 470 Enable compilation of tools/xway-swap-bytes needed for Lantiq 471 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 472 be swapped if a flash programmer is used. 473 474- ARM options: 475 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 476 477 Select high exception vectors of the ARM core, e.g., do not 478 clear the V bit of the c1 register of CP15. 479 480 CONFIG_SYS_THUMB_BUILD 481 482 Use this flag to build U-Boot using the Thumb instruction 483 set for ARM architectures. Thumb instruction set provides 484 better code density. For ARM architectures that support 485 Thumb2 this flag will result in Thumb2 code generated by 486 GCC. 487 488 CONFIG_ARM_ERRATA_716044 489 CONFIG_ARM_ERRATA_742230 490 CONFIG_ARM_ERRATA_743622 491 CONFIG_ARM_ERRATA_751472 492 493 If set, the workarounds for these ARM errata are applied early 494 during U-Boot startup. Note that these options force the 495 workarounds to be applied; no CPU-type/version detection 496 exists, unlike the similar options in the Linux kernel. Do not 497 set these options unless they apply! 498 499- CPU timer options: 500 CONFIG_SYS_HZ 501 502 The frequency of the timer returned by get_timer(). 503 get_timer() must operate in milliseconds and this CONFIG 504 option must be set to 1000. 505 506- Linux Kernel Interface: 507 CONFIG_CLOCKS_IN_MHZ 508 509 U-Boot stores all clock information in Hz 510 internally. For binary compatibility with older Linux 511 kernels (which expect the clocks passed in the 512 bd_info data to be in MHz) the environment variable 513 "clocks_in_mhz" can be defined so that U-Boot 514 converts clock data to MHZ before passing it to the 515 Linux kernel. 516 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 517 "clocks_in_mhz=1" is automatically included in the 518 default environment. 519 520 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 521 522 When transferring memsize parameter to linux, some versions 523 expect it to be in bytes, others in MB. 524 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 525 526 CONFIG_OF_LIBFDT 527 528 New kernel versions are expecting firmware settings to be 529 passed using flattened device trees (based on open firmware 530 concepts). 531 532 CONFIG_OF_LIBFDT 533 * New libfdt-based support 534 * Adds the "fdt" command 535 * The bootm command automatically updates the fdt 536 537 OF_CPU - The proper name of the cpus node (only required for 538 MPC512X and MPC5xxx based boards). 539 OF_SOC - The proper name of the soc node (only required for 540 MPC512X and MPC5xxx based boards). 541 OF_TBCLK - The timebase frequency. 542 OF_STDOUT_PATH - The path to the console device 543 544 boards with QUICC Engines require OF_QE to set UCC MAC 545 addresses 546 547 CONFIG_OF_BOARD_SETUP 548 549 Board code has addition modification that it wants to make 550 to the flat device tree before handing it off to the kernel 551 552 CONFIG_OF_BOOT_CPU 553 554 This define fills in the correct boot CPU in the boot 555 param header, the default value is zero if undefined. 556 557 CONFIG_OF_IDE_FIXUP 558 559 U-Boot can detect if an IDE device is present or not. 560 If not, and this new config option is activated, U-Boot 561 removes the ATA node from the DTS before booting Linux, 562 so the Linux IDE driver does not probe the device and 563 crash. This is needed for buggy hardware (uc101) where 564 no pull down resistor is connected to the signal IDE5V_DD7. 565 566 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 567 568 This setting is mandatory for all boards that have only one 569 machine type and must be used to specify the machine type 570 number as it appears in the ARM machine registry 571 (see http://www.arm.linux.org.uk/developer/machines/). 572 Only boards that have multiple machine types supported 573 in a single configuration file and the machine type is 574 runtime discoverable, do not have to use this setting. 575 576- vxWorks boot parameters: 577 578 bootvx constructs a valid bootline using the following 579 environments variables: bootfile, ipaddr, serverip, hostname. 580 It loads the vxWorks image pointed bootfile. 581 582 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 583 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 584 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 585 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 586 587 CONFIG_SYS_VXWORKS_ADD_PARAMS 588 589 Add it at the end of the bootline. E.g "u=username pw=secret" 590 591 Note: If a "bootargs" environment is defined, it will overwride 592 the defaults discussed just above. 593 594- Cache Configuration: 595 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 596 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 597 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 598 599- Cache Configuration for ARM: 600 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 601 controller 602 CONFIG_SYS_PL310_BASE - Physical base address of PL310 603 controller register space 604 605- Serial Ports: 606 CONFIG_PL010_SERIAL 607 608 Define this if you want support for Amba PrimeCell PL010 UARTs. 609 610 CONFIG_PL011_SERIAL 611 612 Define this if you want support for Amba PrimeCell PL011 UARTs. 613 614 CONFIG_PL011_CLOCK 615 616 If you have Amba PrimeCell PL011 UARTs, set this variable to 617 the clock speed of the UARTs. 618 619 CONFIG_PL01x_PORTS 620 621 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 622 define this to a list of base addresses for each (supported) 623 port. See e.g. include/configs/versatile.h 624 625 CONFIG_PL011_SERIAL_RLCR 626 627 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 628 have separate receive and transmit line control registers. Set 629 this variable to initialize the extra register. 630 631 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 632 633 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 634 boot loader that has already initialized the UART. Define this 635 variable to flush the UART at init time. 636 637 CONFIG_SYS_NS16550_BROKEN_TEMT 638 639 16550 UART set the Transmitter Empty (TEMT) Bit when all output 640 has finished and the transmitter is totally empty. U-Boot waits 641 for this bit to be set to initialize the serial console. On some 642 broken platforms this bit is not set in SPL making U-Boot to 643 hang while waiting for TEMT. Define this option to avoid it. 644 645 646- Console Interface: 647 Depending on board, define exactly one serial port 648 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 649 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 650 console by defining CONFIG_8xx_CONS_NONE 651 652 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 653 port routines must be defined elsewhere 654 (i.e. serial_init(), serial_getc(), ...) 655 656 CONFIG_CFB_CONSOLE 657 Enables console device for a color framebuffer. Needs following 658 defines (cf. smiLynxEM, i8042) 659 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 660 (default big endian) 661 VIDEO_HW_RECTFILL graphic chip supports 662 rectangle fill 663 (cf. smiLynxEM) 664 VIDEO_HW_BITBLT graphic chip supports 665 bit-blit (cf. smiLynxEM) 666 VIDEO_VISIBLE_COLS visible pixel columns 667 (cols=pitch) 668 VIDEO_VISIBLE_ROWS visible pixel rows 669 VIDEO_PIXEL_SIZE bytes per pixel 670 VIDEO_DATA_FORMAT graphic data format 671 (0-5, cf. cfb_console.c) 672 VIDEO_FB_ADRS framebuffer address 673 VIDEO_KBD_INIT_FCT keyboard int fct 674 (i.e. i8042_kbd_init()) 675 VIDEO_TSTC_FCT test char fct 676 (i.e. i8042_tstc) 677 VIDEO_GETC_FCT get char fct 678 (i.e. i8042_getc) 679 CONFIG_CONSOLE_CURSOR cursor drawing on/off 680 (requires blink timer 681 cf. i8042.c) 682 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 683 CONFIG_CONSOLE_TIME display time/date info in 684 upper right corner 685 (requires CONFIG_CMD_DATE) 686 CONFIG_VIDEO_LOGO display Linux logo in 687 upper left corner 688 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 689 linux_logo.h for logo. 690 Requires CONFIG_VIDEO_LOGO 691 CONFIG_CONSOLE_EXTRA_INFO 692 additional board info beside 693 the logo 694 695 When CONFIG_CFB_CONSOLE_ANSI is defined, console will support 696 a limited number of ANSI escape sequences (cursor control, 697 erase functions and limited graphics rendition control). 698 699 When CONFIG_CFB_CONSOLE is defined, video console is 700 default i/o. Serial console can be forced with 701 environment 'console=serial'. 702 703 When CONFIG_SILENT_CONSOLE is defined, all console 704 messages (by U-Boot and Linux!) can be silenced with 705 the "silent" environment variable. See 706 doc/README.silent for more information. 707 708- Console Baudrate: 709 CONFIG_BAUDRATE - in bps 710 Select one of the baudrates listed in 711 CONFIG_SYS_BAUDRATE_TABLE, see below. 712 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 713 714- Console Rx buffer length 715 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 716 the maximum receive buffer length for the SMC. 717 This option is actual only for 82xx and 8xx possible. 718 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 719 must be defined, to setup the maximum idle timeout for 720 the SMC. 721 722- Pre-Console Buffer: 723 Prior to the console being initialised (i.e. serial UART 724 initialised etc) all console output is silently discarded. 725 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 726 buffer any console messages prior to the console being 727 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 728 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 729 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 730 bytes are output before the console is initialised, the 731 earlier bytes are discarded. 732 733 'Sane' compilers will generate smaller code if 734 CONFIG_PRE_CON_BUF_SZ is a power of 2 735 736- Safe printf() functions 737 Define CONFIG_SYS_VSNPRINTF to compile in safe versions of 738 the printf() functions. These are defined in 739 include/vsprintf.h and include snprintf(), vsnprintf() and 740 so on. Code size increase is approximately 300-500 bytes. 741 If this option is not given then these functions will 742 silently discard their buffer size argument - this means 743 you are not getting any overflow checking in this case. 744 745- Boot Delay: CONFIG_BOOTDELAY - in seconds 746 Delay before automatically booting the default image; 747 set to -1 to disable autoboot. 748 set to -2 to autoboot with no delay and not check for abort 749 (even when CONFIG_ZERO_BOOTDELAY_CHECK is defined). 750 751 See doc/README.autoboot for these options that 752 work with CONFIG_BOOTDELAY. None are required. 753 CONFIG_BOOT_RETRY_TIME 754 CONFIG_BOOT_RETRY_MIN 755 CONFIG_AUTOBOOT_KEYED 756 CONFIG_AUTOBOOT_PROMPT 757 CONFIG_AUTOBOOT_DELAY_STR 758 CONFIG_AUTOBOOT_STOP_STR 759 CONFIG_AUTOBOOT_DELAY_STR2 760 CONFIG_AUTOBOOT_STOP_STR2 761 CONFIG_ZERO_BOOTDELAY_CHECK 762 CONFIG_RESET_TO_RETRY 763 764- Autoboot Command: 765 CONFIG_BOOTCOMMAND 766 Only needed when CONFIG_BOOTDELAY is enabled; 767 define a command string that is automatically executed 768 when no character is read on the console interface 769 within "Boot Delay" after reset. 770 771 CONFIG_BOOTARGS 772 This can be used to pass arguments to the bootm 773 command. The value of CONFIG_BOOTARGS goes into the 774 environment value "bootargs". 775 776 CONFIG_RAMBOOT and CONFIG_NFSBOOT 777 The value of these goes into the environment as 778 "ramboot" and "nfsboot" respectively, and can be used 779 as a convenience, when switching between booting from 780 RAM and NFS. 781 782- Pre-Boot Commands: 783 CONFIG_PREBOOT 784 785 When this option is #defined, the existence of the 786 environment variable "preboot" will be checked 787 immediately before starting the CONFIG_BOOTDELAY 788 countdown and/or running the auto-boot command resp. 789 entering interactive mode. 790 791 This feature is especially useful when "preboot" is 792 automatically generated or modified. For an example 793 see the LWMON board specific code: here "preboot" is 794 modified when the user holds down a certain 795 combination of keys on the (special) keyboard when 796 booting the systems 797 798- Serial Download Echo Mode: 799 CONFIG_LOADS_ECHO 800 If defined to 1, all characters received during a 801 serial download (using the "loads" command) are 802 echoed back. This might be needed by some terminal 803 emulations (like "cu"), but may as well just take 804 time on others. This setting #define's the initial 805 value of the "loads_echo" environment variable. 806 807- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 808 CONFIG_KGDB_BAUDRATE 809 Select one of the baudrates listed in 810 CONFIG_SYS_BAUDRATE_TABLE, see below. 811 812- Monitor Functions: 813 Monitor commands can be included or excluded 814 from the build by using the #include files 815 <config_cmd_all.h> and #undef'ing unwanted 816 commands, or using <config_cmd_default.h> 817 and augmenting with additional #define's 818 for wanted commands. 819 820 The default command configuration includes all commands 821 except those marked below with a "*". 822 823 CONFIG_CMD_ASKENV * ask for env variable 824 CONFIG_CMD_BDI bdinfo 825 CONFIG_CMD_BEDBUG * Include BedBug Debugger 826 CONFIG_CMD_BMP * BMP support 827 CONFIG_CMD_BSP * Board specific commands 828 CONFIG_CMD_BOOTD bootd 829 CONFIG_CMD_CACHE * icache, dcache 830 CONFIG_CMD_CONSOLE coninfo 831 CONFIG_CMD_CRC32 * crc32 832 CONFIG_CMD_DATE * support for RTC, date/time... 833 CONFIG_CMD_DHCP * DHCP support 834 CONFIG_CMD_DIAG * Diagnostics 835 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 836 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 837 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 838 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 839 CONFIG_CMD_DTT * Digital Therm and Thermostat 840 CONFIG_CMD_ECHO echo arguments 841 CONFIG_CMD_EDITENV edit env variable 842 CONFIG_CMD_EEPROM * EEPROM read/write support 843 CONFIG_CMD_ELF * bootelf, bootvx 844 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 845 CONFIG_CMD_ENV_FLAGS * display details about env flags 846 CONFIG_CMD_EXPORTENV * export the environment 847 CONFIG_CMD_EXT2 * ext2 command support 848 CONFIG_CMD_EXT4 * ext4 command support 849 CONFIG_CMD_SAVEENV saveenv 850 CONFIG_CMD_FDC * Floppy Disk Support 851 CONFIG_CMD_FAT * FAT command support 852 CONFIG_CMD_FDOS * Dos diskette Support 853 CONFIG_CMD_FLASH flinfo, erase, protect 854 CONFIG_CMD_FPGA FPGA device initialization support 855 CONFIG_CMD_GETTIME * Get time since boot 856 CONFIG_CMD_GO * the 'go' command (exec code) 857 CONFIG_CMD_GREPENV * search environment 858 CONFIG_CMD_HASH * calculate hash / digest 859 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 860 CONFIG_CMD_I2C * I2C serial bus support 861 CONFIG_CMD_IDE * IDE harddisk support 862 CONFIG_CMD_IMI iminfo 863 CONFIG_CMD_IMLS List all images found in NOR flash 864 CONFIG_CMD_IMLS_NAND List all images found in NAND flash 865 CONFIG_CMD_IMMAP * IMMR dump support 866 CONFIG_CMD_IMPORTENV * import an environment 867 CONFIG_CMD_INI * import data from an ini file into the env 868 CONFIG_CMD_IRQ * irqinfo 869 CONFIG_CMD_ITEST Integer/string test of 2 values 870 CONFIG_CMD_JFFS2 * JFFS2 Support 871 CONFIG_CMD_KGDB * kgdb 872 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader) 873 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 874 (169.254.*.*) 875 CONFIG_CMD_LOADB loadb 876 CONFIG_CMD_LOADS loads 877 CONFIG_CMD_MD5SUM print md5 message digest 878 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 879 CONFIG_CMD_MEMINFO * Display detailed memory information 880 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 881 loop, loopw 882 CONFIG_CMD_MEMTEST mtest 883 CONFIG_CMD_MISC Misc functions like sleep etc 884 CONFIG_CMD_MMC * MMC memory mapped support 885 CONFIG_CMD_MII * MII utility commands 886 CONFIG_CMD_MTDPARTS * MTD partition support 887 CONFIG_CMD_NAND * NAND support 888 CONFIG_CMD_NET bootp, tftpboot, rarpboot 889 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 890 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 891 CONFIG_CMD_PCI * pciinfo 892 CONFIG_CMD_PCMCIA * PCMCIA support 893 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 894 host 895 CONFIG_CMD_PORTIO * Port I/O 896 CONFIG_CMD_READ * Read raw data from partition 897 CONFIG_CMD_REGINFO * Register dump 898 CONFIG_CMD_RUN run command in env variable 899 CONFIG_CMD_SANDBOX * sb command to access sandbox features 900 CONFIG_CMD_SAVES * save S record dump 901 CONFIG_CMD_SCSI * SCSI Support 902 CONFIG_CMD_SDRAM * print SDRAM configuration information 903 (requires CONFIG_CMD_I2C) 904 CONFIG_CMD_SETGETDCR Support for DCR Register access 905 (4xx only) 906 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 907 CONFIG_CMD_SHA1SUM print sha1 memory digest 908 (requires CONFIG_CMD_MEMORY) 909 CONFIG_CMD_SOURCE "source" command Support 910 CONFIG_CMD_SPI * SPI serial bus support 911 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 912 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 913 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 914 CONFIG_CMD_TIMER * access to the system tick timer 915 CONFIG_CMD_USB * USB support 916 CONFIG_CMD_CDP * Cisco Discover Protocol support 917 CONFIG_CMD_MFSL * Microblaze FSL support 918 919 920 EXAMPLE: If you want all functions except of network 921 support you can write: 922 923 #include "config_cmd_all.h" 924 #undef CONFIG_CMD_NET 925 926 Other Commands: 927 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 928 929 Note: Don't enable the "icache" and "dcache" commands 930 (configuration option CONFIG_CMD_CACHE) unless you know 931 what you (and your U-Boot users) are doing. Data 932 cache cannot be enabled on systems like the 8xx or 933 8260 (where accesses to the IMMR region must be 934 uncached), and it cannot be disabled on all other 935 systems where we (mis-) use the data cache to hold an 936 initial stack and some data. 937 938 939 XXX - this list needs to get updated! 940 941- Device tree: 942 CONFIG_OF_CONTROL 943 If this variable is defined, U-Boot will use a device tree 944 to configure its devices, instead of relying on statically 945 compiled #defines in the board file. This option is 946 experimental and only available on a few boards. The device 947 tree is available in the global data as gd->fdt_blob. 948 949 U-Boot needs to get its device tree from somewhere. This can 950 be done using one of the two options below: 951 952 CONFIG_OF_EMBED 953 If this variable is defined, U-Boot will embed a device tree 954 binary in its image. This device tree file should be in the 955 board directory and called <soc>-<board>.dts. The binary file 956 is then picked up in board_init_f() and made available through 957 the global data structure as gd->blob. 958 959 CONFIG_OF_SEPARATE 960 If this variable is defined, U-Boot will build a device tree 961 binary. It will be called u-boot.dtb. Architecture-specific 962 code will locate it at run-time. Generally this works by: 963 964 cat u-boot.bin u-boot.dtb >image.bin 965 966 and in fact, U-Boot does this for you, creating a file called 967 u-boot-dtb.bin which is useful in the common case. You can 968 still use the individual files if you need something more 969 exotic. 970 971- Watchdog: 972 CONFIG_WATCHDOG 973 If this variable is defined, it enables watchdog 974 support for the SoC. There must be support in the SoC 975 specific code for a watchdog. For the 8xx and 8260 976 CPUs, the SIU Watchdog feature is enabled in the SYPCR 977 register. When supported for a specific SoC is 978 available, then no further board specific code should 979 be needed to use it. 980 981 CONFIG_HW_WATCHDOG 982 When using a watchdog circuitry external to the used 983 SoC, then define this variable and provide board 984 specific code for the "hw_watchdog_reset" function. 985 986- U-Boot Version: 987 CONFIG_VERSION_VARIABLE 988 If this variable is defined, an environment variable 989 named "ver" is created by U-Boot showing the U-Boot 990 version as printed by the "version" command. 991 Any change to this variable will be reverted at the 992 next reset. 993 994- Real-Time Clock: 995 996 When CONFIG_CMD_DATE is selected, the type of the RTC 997 has to be selected, too. Define exactly one of the 998 following options: 999 1000 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1001 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1002 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1003 CONFIG_RTC_MC146818 - use MC146818 RTC 1004 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1005 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1006 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1007 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1008 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1009 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1010 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1011 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1012 RV3029 RTC. 1013 1014 Note that if the RTC uses I2C, then the I2C interface 1015 must also be configured. See I2C Support, below. 1016 1017- GPIO Support: 1018 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1019 CONFIG_PCA953X_INFO - enable pca953x info command 1020 1021 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1022 chip-ngpio pairs that tell the PCA953X driver the number of 1023 pins supported by a particular chip. 1024 1025 Note that if the GPIO device uses I2C, then the I2C interface 1026 must also be configured. See I2C Support, below. 1027 1028- Timestamp Support: 1029 1030 When CONFIG_TIMESTAMP is selected, the timestamp 1031 (date and time) of an image is printed by image 1032 commands like bootm or iminfo. This option is 1033 automatically enabled when you select CONFIG_CMD_DATE . 1034 1035- Partition Labels (disklabels) Supported: 1036 Zero or more of the following: 1037 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1038 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1039 Intel architecture, USB sticks, etc. 1040 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1041 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1042 bootloader. Note 2TB partition limit; see 1043 disk/part_efi.c 1044 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1045 1046 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1047 CONFIG_CMD_SCSI) you must configure support for at 1048 least one non-MTD partition type as well. 1049 1050- IDE Reset method: 1051 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1052 board configurations files but used nowhere! 1053 1054 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1055 be performed by calling the function 1056 ide_set_reset(int reset) 1057 which has to be defined in a board specific file 1058 1059- ATAPI Support: 1060 CONFIG_ATAPI 1061 1062 Set this to enable ATAPI support. 1063 1064- LBA48 Support 1065 CONFIG_LBA48 1066 1067 Set this to enable support for disks larger than 137GB 1068 Also look at CONFIG_SYS_64BIT_LBA. 1069 Whithout these , LBA48 support uses 32bit variables and will 'only' 1070 support disks up to 2.1TB. 1071 1072 CONFIG_SYS_64BIT_LBA: 1073 When enabled, makes the IDE subsystem use 64bit sector addresses. 1074 Default is 32bit. 1075 1076- SCSI Support: 1077 At the moment only there is only support for the 1078 SYM53C8XX SCSI controller; define 1079 CONFIG_SCSI_SYM53C8XX to enable it. 1080 1081 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1082 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1083 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1084 maximum numbers of LUNs, SCSI ID's and target 1085 devices. 1086 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1087 1088 The environment variable 'scsidevs' is set to the number of 1089 SCSI devices found during the last scan. 1090 1091- NETWORK Support (PCI): 1092 CONFIG_E1000 1093 Support for Intel 8254x/8257x gigabit chips. 1094 1095 CONFIG_E1000_SPI 1096 Utility code for direct access to the SPI bus on Intel 8257x. 1097 This does not do anything useful unless you set at least one 1098 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1099 1100 CONFIG_E1000_SPI_GENERIC 1101 Allow generic access to the SPI bus on the Intel 8257x, for 1102 example with the "sspi" command. 1103 1104 CONFIG_CMD_E1000 1105 Management command for E1000 devices. When used on devices 1106 with SPI support you can reprogram the EEPROM from U-Boot. 1107 1108 CONFIG_E1000_FALLBACK_MAC 1109 default MAC for empty EEPROM after production. 1110 1111 CONFIG_EEPRO100 1112 Support for Intel 82557/82559/82559ER chips. 1113 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1114 write routine for first time initialisation. 1115 1116 CONFIG_TULIP 1117 Support for Digital 2114x chips. 1118 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1119 modem chip initialisation (KS8761/QS6611). 1120 1121 CONFIG_NATSEMI 1122 Support for National dp83815 chips. 1123 1124 CONFIG_NS8382X 1125 Support for National dp8382[01] gigabit chips. 1126 1127- NETWORK Support (other): 1128 1129 CONFIG_DRIVER_AT91EMAC 1130 Support for AT91RM9200 EMAC. 1131 1132 CONFIG_RMII 1133 Define this to use reduced MII inteface 1134 1135 CONFIG_DRIVER_AT91EMAC_QUIET 1136 If this defined, the driver is quiet. 1137 The driver doen't show link status messages. 1138 1139 CONFIG_CALXEDA_XGMAC 1140 Support for the Calxeda XGMAC device 1141 1142 CONFIG_LAN91C96 1143 Support for SMSC's LAN91C96 chips. 1144 1145 CONFIG_LAN91C96_BASE 1146 Define this to hold the physical address 1147 of the LAN91C96's I/O space 1148 1149 CONFIG_LAN91C96_USE_32_BIT 1150 Define this to enable 32 bit addressing 1151 1152 CONFIG_SMC91111 1153 Support for SMSC's LAN91C111 chip 1154 1155 CONFIG_SMC91111_BASE 1156 Define this to hold the physical address 1157 of the device (I/O space) 1158 1159 CONFIG_SMC_USE_32_BIT 1160 Define this if data bus is 32 bits 1161 1162 CONFIG_SMC_USE_IOFUNCS 1163 Define this to use i/o functions instead of macros 1164 (some hardware wont work with macros) 1165 1166 CONFIG_DRIVER_TI_EMAC 1167 Support for davinci emac 1168 1169 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1170 Define this if you have more then 3 PHYs. 1171 1172 CONFIG_FTGMAC100 1173 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1174 1175 CONFIG_FTGMAC100_EGIGA 1176 Define this to use GE link update with gigabit PHY. 1177 Define this if FTGMAC100 is connected to gigabit PHY. 1178 If your system has 10/100 PHY only, it might not occur 1179 wrong behavior. Because PHY usually return timeout or 1180 useless data when polling gigabit status and gigabit 1181 control registers. This behavior won't affect the 1182 correctnessof 10/100 link speed update. 1183 1184 CONFIG_SMC911X 1185 Support for SMSC's LAN911x and LAN921x chips 1186 1187 CONFIG_SMC911X_BASE 1188 Define this to hold the physical address 1189 of the device (I/O space) 1190 1191 CONFIG_SMC911X_32_BIT 1192 Define this if data bus is 32 bits 1193 1194 CONFIG_SMC911X_16_BIT 1195 Define this if data bus is 16 bits. If your processor 1196 automatically converts one 32 bit word to two 16 bit 1197 words you may also try CONFIG_SMC911X_32_BIT. 1198 1199 CONFIG_SH_ETHER 1200 Support for Renesas on-chip Ethernet controller 1201 1202 CONFIG_SH_ETHER_USE_PORT 1203 Define the number of ports to be used 1204 1205 CONFIG_SH_ETHER_PHY_ADDR 1206 Define the ETH PHY's address 1207 1208 CONFIG_SH_ETHER_CACHE_WRITEBACK 1209 If this option is set, the driver enables cache flush. 1210 1211- TPM Support: 1212 CONFIG_GENERIC_LPC_TPM 1213 Support for generic parallel port TPM devices. Only one device 1214 per system is supported at this time. 1215 1216 CONFIG_TPM_TIS_BASE_ADDRESS 1217 Base address where the generic TPM device is mapped 1218 to. Contemporary x86 systems usually map it at 1219 0xfed40000. 1220 1221- USB Support: 1222 At the moment only the UHCI host controller is 1223 supported (PIP405, MIP405, MPC5200); define 1224 CONFIG_USB_UHCI to enable it. 1225 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1226 and define CONFIG_USB_STORAGE to enable the USB 1227 storage devices. 1228 Note: 1229 Supported are USB Keyboards and USB Floppy drives 1230 (TEAC FD-05PUB). 1231 MPC5200 USB requires additional defines: 1232 CONFIG_USB_CLOCK 1233 for 528 MHz Clock: 0x0001bbbb 1234 CONFIG_PSC3_USB 1235 for USB on PSC3 1236 CONFIG_USB_CONFIG 1237 for differential drivers: 0x00001000 1238 for single ended drivers: 0x00005000 1239 for differential drivers on PSC3: 0x00000100 1240 for single ended drivers on PSC3: 0x00004100 1241 CONFIG_SYS_USB_EVENT_POLL 1242 May be defined to allow interrupt polling 1243 instead of using asynchronous interrupts 1244 1245 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1246 txfilltuning field in the EHCI controller on reset. 1247 1248- USB Device: 1249 Define the below if you wish to use the USB console. 1250 Once firmware is rebuilt from a serial console issue the 1251 command "setenv stdin usbtty; setenv stdout usbtty" and 1252 attach your USB cable. The Unix command "dmesg" should print 1253 it has found a new device. The environment variable usbtty 1254 can be set to gserial or cdc_acm to enable your device to 1255 appear to a USB host as a Linux gserial device or a 1256 Common Device Class Abstract Control Model serial device. 1257 If you select usbtty = gserial you should be able to enumerate 1258 a Linux host by 1259 # modprobe usbserial vendor=0xVendorID product=0xProductID 1260 else if using cdc_acm, simply setting the environment 1261 variable usbtty to be cdc_acm should suffice. The following 1262 might be defined in YourBoardName.h 1263 1264 CONFIG_USB_DEVICE 1265 Define this to build a UDC device 1266 1267 CONFIG_USB_TTY 1268 Define this to have a tty type of device available to 1269 talk to the UDC device 1270 1271 CONFIG_USBD_HS 1272 Define this to enable the high speed support for usb 1273 device and usbtty. If this feature is enabled, a routine 1274 int is_usbd_high_speed(void) 1275 also needs to be defined by the driver to dynamically poll 1276 whether the enumeration has succeded at high speed or full 1277 speed. 1278 1279 CONFIG_SYS_CONSOLE_IS_IN_ENV 1280 Define this if you want stdin, stdout &/or stderr to 1281 be set to usbtty. 1282 1283 mpc8xx: 1284 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1285 Derive USB clock from external clock "blah" 1286 - CONFIG_SYS_USB_EXTC_CLK 0x02 1287 1288 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1289 Derive USB clock from brgclk 1290 - CONFIG_SYS_USB_BRG_CLK 0x04 1291 1292 If you have a USB-IF assigned VendorID then you may wish to 1293 define your own vendor specific values either in BoardName.h 1294 or directly in usbd_vendor_info.h. If you don't define 1295 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1296 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1297 should pretend to be a Linux device to it's target host. 1298 1299 CONFIG_USBD_MANUFACTURER 1300 Define this string as the name of your company for 1301 - CONFIG_USBD_MANUFACTURER "my company" 1302 1303 CONFIG_USBD_PRODUCT_NAME 1304 Define this string as the name of your product 1305 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1306 1307 CONFIG_USBD_VENDORID 1308 Define this as your assigned Vendor ID from the USB 1309 Implementors Forum. This *must* be a genuine Vendor ID 1310 to avoid polluting the USB namespace. 1311 - CONFIG_USBD_VENDORID 0xFFFF 1312 1313 CONFIG_USBD_PRODUCTID 1314 Define this as the unique Product ID 1315 for your device 1316 - CONFIG_USBD_PRODUCTID 0xFFFF 1317 1318- ULPI Layer Support: 1319 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1320 the generic ULPI layer. The generic layer accesses the ULPI PHY 1321 via the platform viewport, so you need both the genric layer and 1322 the viewport enabled. Currently only Chipidea/ARC based 1323 viewport is supported. 1324 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1325 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1326 If your ULPI phy needs a different reference clock than the 1327 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1328 the appropriate value in Hz. 1329 1330- MMC Support: 1331 The MMC controller on the Intel PXA is supported. To 1332 enable this define CONFIG_MMC. The MMC can be 1333 accessed from the boot prompt by mapping the device 1334 to physical memory similar to flash. Command line is 1335 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1336 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1337 1338 CONFIG_SH_MMCIF 1339 Support for Renesas on-chip MMCIF controller 1340 1341 CONFIG_SH_MMCIF_ADDR 1342 Define the base address of MMCIF registers 1343 1344 CONFIG_SH_MMCIF_CLK 1345 Define the clock frequency for MMCIF 1346 1347- Journaling Flash filesystem support: 1348 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1349 CONFIG_JFFS2_NAND_DEV 1350 Define these for a default partition on a NAND device 1351 1352 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1353 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1354 Define these for a default partition on a NOR device 1355 1356 CONFIG_SYS_JFFS_CUSTOM_PART 1357 Define this to create an own partition. You have to provide a 1358 function struct part_info* jffs2_part_info(int part_num) 1359 1360 If you define only one JFFS2 partition you may also want to 1361 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1362 to disable the command chpart. This is the default when you 1363 have not defined a custom partition 1364 1365- FAT(File Allocation Table) filesystem write function support: 1366 CONFIG_FAT_WRITE 1367 1368 Define this to enable support for saving memory data as a 1369 file in FAT formatted partition. 1370 1371 This will also enable the command "fatwrite" enabling the 1372 user to write files to FAT. 1373 1374CBFS (Coreboot Filesystem) support 1375 CONFIG_CMD_CBFS 1376 1377 Define this to enable support for reading from a Coreboot 1378 filesystem. Available commands are cbfsinit, cbfsinfo, cbfsls 1379 and cbfsload. 1380 1381- Keyboard Support: 1382 CONFIG_ISA_KEYBOARD 1383 1384 Define this to enable standard (PC-Style) keyboard 1385 support 1386 1387 CONFIG_I8042_KBD 1388 Standard PC keyboard driver with US (is default) and 1389 GERMAN key layout (switch via environment 'keymap=de') support. 1390 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1391 for cfb_console. Supports cursor blinking. 1392 1393- Video support: 1394 CONFIG_VIDEO 1395 1396 Define this to enable video support (for output to 1397 video). 1398 1399 CONFIG_VIDEO_CT69000 1400 1401 Enable Chips & Technologies 69000 Video chip 1402 1403 CONFIG_VIDEO_SMI_LYNXEM 1404 Enable Silicon Motion SMI 712/710/810 Video chip. The 1405 video output is selected via environment 'videoout' 1406 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1407 assumed. 1408 1409 For the CT69000 and SMI_LYNXEM drivers, videomode is 1410 selected via environment 'videomode'. Two different ways 1411 are possible: 1412 - "videomode=num" 'num' is a standard LiLo mode numbers. 1413 Following standard modes are supported (* is default): 1414 1415 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1416 -------------+--------------------------------------------- 1417 8 bits | 0x301* 0x303 0x305 0x161 0x307 1418 15 bits | 0x310 0x313 0x316 0x162 0x319 1419 16 bits | 0x311 0x314 0x317 0x163 0x31A 1420 24 bits | 0x312 0x315 0x318 ? 0x31B 1421 -------------+--------------------------------------------- 1422 (i.e. setenv videomode 317; saveenv; reset;) 1423 1424 - "videomode=bootargs" all the video parameters are parsed 1425 from the bootargs. (See drivers/video/videomodes.c) 1426 1427 1428 CONFIG_VIDEO_SED13806 1429 Enable Epson SED13806 driver. This driver supports 8bpp 1430 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1431 or CONFIG_VIDEO_SED13806_16BPP 1432 1433 CONFIG_FSL_DIU_FB 1434 Enable the Freescale DIU video driver. Reference boards for 1435 SOCs that have a DIU should define this macro to enable DIU 1436 support, and should also define these other macros: 1437 1438 CONFIG_SYS_DIU_ADDR 1439 CONFIG_VIDEO 1440 CONFIG_CMD_BMP 1441 CONFIG_CFB_CONSOLE 1442 CONFIG_VIDEO_SW_CURSOR 1443 CONFIG_VGA_AS_SINGLE_DEVICE 1444 CONFIG_VIDEO_LOGO 1445 CONFIG_VIDEO_BMP_LOGO 1446 1447 The DIU driver will look for the 'video-mode' environment 1448 variable, and if defined, enable the DIU as a console during 1449 boot. See the documentation file README.video for a 1450 description of this variable. 1451 1452 CONFIG_VIDEO_VGA 1453 1454 Enable the VGA video / BIOS for x86. The alternative if you 1455 are using coreboot is to use the coreboot frame buffer 1456 driver. 1457 1458 1459- Keyboard Support: 1460 CONFIG_KEYBOARD 1461 1462 Define this to enable a custom keyboard support. 1463 This simply calls drv_keyboard_init() which must be 1464 defined in your board-specific files. 1465 The only board using this so far is RBC823. 1466 1467- LCD Support: CONFIG_LCD 1468 1469 Define this to enable LCD support (for output to LCD 1470 display); also select one of the supported displays 1471 by defining one of these: 1472 1473 CONFIG_ATMEL_LCD: 1474 1475 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1476 1477 CONFIG_NEC_NL6448AC33: 1478 1479 NEC NL6448AC33-18. Active, color, single scan. 1480 1481 CONFIG_NEC_NL6448BC20 1482 1483 NEC NL6448BC20-08. 6.5", 640x480. 1484 Active, color, single scan. 1485 1486 CONFIG_NEC_NL6448BC33_54 1487 1488 NEC NL6448BC33-54. 10.4", 640x480. 1489 Active, color, single scan. 1490 1491 CONFIG_SHARP_16x9 1492 1493 Sharp 320x240. Active, color, single scan. 1494 It isn't 16x9, and I am not sure what it is. 1495 1496 CONFIG_SHARP_LQ64D341 1497 1498 Sharp LQ64D341 display, 640x480. 1499 Active, color, single scan. 1500 1501 CONFIG_HLD1045 1502 1503 HLD1045 display, 640x480. 1504 Active, color, single scan. 1505 1506 CONFIG_OPTREX_BW 1507 1508 Optrex CBL50840-2 NF-FW 99 22 M5 1509 or 1510 Hitachi LMG6912RPFC-00T 1511 or 1512 Hitachi SP14Q002 1513 1514 320x240. Black & white. 1515 1516 Normally display is black on white background; define 1517 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1518 1519 CONFIG_LCD_ALIGNMENT 1520 1521 Normally the LCD is page-aligned (tyically 4KB). If this is 1522 defined then the LCD will be aligned to this value instead. 1523 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1524 here, since it is cheaper to change data cache settings on 1525 a per-section basis. 1526 1527 CONFIG_CONSOLE_SCROLL_LINES 1528 1529 When the console need to be scrolled, this is the number of 1530 lines to scroll by. It defaults to 1. Increasing this makes 1531 the console jump but can help speed up operation when scrolling 1532 is slow. 1533 1534 CONFIG_LCD_BMP_RLE8 1535 1536 Support drawing of RLE8-compressed bitmaps on the LCD. 1537 1538 CONFIG_I2C_EDID 1539 1540 Enables an 'i2c edid' command which can read EDID 1541 information over I2C from an attached LCD display. 1542 1543- Splash Screen Support: CONFIG_SPLASH_SCREEN 1544 1545 If this option is set, the environment is checked for 1546 a variable "splashimage". If found, the usual display 1547 of logo, copyright and system information on the LCD 1548 is suppressed and the BMP image at the address 1549 specified in "splashimage" is loaded instead. The 1550 console is redirected to the "nulldev", too. This 1551 allows for a "silent" boot where a splash screen is 1552 loaded very quickly after power-on. 1553 1554 CONFIG_SPLASHIMAGE_GUARD 1555 1556 If this option is set, then U-Boot will prevent the environment 1557 variable "splashimage" from being set to a problematic address 1558 (see README.displaying-bmps and README.arm-unaligned-accesses). 1559 This option is useful for targets where, due to alignment 1560 restrictions, an improperly aligned BMP image will cause a data 1561 abort. If you think you will not have problems with unaligned 1562 accesses (for example because your toolchain prevents them) 1563 there is no need to set this option. 1564 1565 CONFIG_SPLASH_SCREEN_ALIGN 1566 1567 If this option is set the splash image can be freely positioned 1568 on the screen. Environment variable "splashpos" specifies the 1569 position as "x,y". If a positive number is given it is used as 1570 number of pixel from left/top. If a negative number is given it 1571 is used as number of pixel from right/bottom. You can also 1572 specify 'm' for centering the image. 1573 1574 Example: 1575 setenv splashpos m,m 1576 => image at center of screen 1577 1578 setenv splashpos 30,20 1579 => image at x = 30 and y = 20 1580 1581 setenv splashpos -10,m 1582 => vertically centered image 1583 at x = dspWidth - bmpWidth - 9 1584 1585 CONFIG_SPLASH_SCREEN_PREPARE 1586 1587 If this option is set then the board_splash_screen_prepare() 1588 function, which must be defined in your code, is called as part 1589 of the splash screen display sequence. It gives the board an 1590 opportunity to prepare the splash image data before it is 1591 processed and sent to the frame buffer by U-Boot. 1592 1593- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1594 1595 If this option is set, additionally to standard BMP 1596 images, gzipped BMP images can be displayed via the 1597 splashscreen support or the bmp command. 1598 1599- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1600 1601 If this option is set, 8-bit RLE compressed BMP images 1602 can be displayed via the splashscreen support or the 1603 bmp command. 1604 1605- Do compresssing for memory range: 1606 CONFIG_CMD_ZIP 1607 1608 If this option is set, it would use zlib deflate method 1609 to compress the specified memory at its best effort. 1610 1611- Compression support: 1612 CONFIG_BZIP2 1613 1614 If this option is set, support for bzip2 compressed 1615 images is included. If not, only uncompressed and gzip 1616 compressed images are supported. 1617 1618 NOTE: the bzip2 algorithm requires a lot of RAM, so 1619 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1620 be at least 4MB. 1621 1622 CONFIG_LZMA 1623 1624 If this option is set, support for lzma compressed 1625 images is included. 1626 1627 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1628 requires an amount of dynamic memory that is given by the 1629 formula: 1630 1631 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1632 1633 Where lc and lp stand for, respectively, Literal context bits 1634 and Literal pos bits. 1635 1636 This value is upper-bounded by 14MB in the worst case. Anyway, 1637 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1638 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1639 a very small buffer. 1640 1641 Use the lzmainfo tool to determinate the lc and lp values and 1642 then calculate the amount of needed dynamic memory (ensuring 1643 the appropriate CONFIG_SYS_MALLOC_LEN value). 1644 1645- MII/PHY support: 1646 CONFIG_PHY_ADDR 1647 1648 The address of PHY on MII bus. 1649 1650 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1651 1652 The clock frequency of the MII bus 1653 1654 CONFIG_PHY_GIGE 1655 1656 If this option is set, support for speed/duplex 1657 detection of gigabit PHY is included. 1658 1659 CONFIG_PHY_RESET_DELAY 1660 1661 Some PHY like Intel LXT971A need extra delay after 1662 reset before any MII register access is possible. 1663 For such PHY, set this option to the usec delay 1664 required. (minimum 300usec for LXT971A) 1665 1666 CONFIG_PHY_CMD_DELAY (ppc4xx) 1667 1668 Some PHY like Intel LXT971A need extra delay after 1669 command issued before MII status register can be read 1670 1671- Ethernet address: 1672 CONFIG_ETHADDR 1673 CONFIG_ETH1ADDR 1674 CONFIG_ETH2ADDR 1675 CONFIG_ETH3ADDR 1676 CONFIG_ETH4ADDR 1677 CONFIG_ETH5ADDR 1678 1679 Define a default value for Ethernet address to use 1680 for the respective Ethernet interface, in case this 1681 is not determined automatically. 1682 1683- IP address: 1684 CONFIG_IPADDR 1685 1686 Define a default value for the IP address to use for 1687 the default Ethernet interface, in case this is not 1688 determined through e.g. bootp. 1689 (Environment variable "ipaddr") 1690 1691- Server IP address: 1692 CONFIG_SERVERIP 1693 1694 Defines a default value for the IP address of a TFTP 1695 server to contact when using the "tftboot" command. 1696 (Environment variable "serverip") 1697 1698 CONFIG_KEEP_SERVERADDR 1699 1700 Keeps the server's MAC address, in the env 'serveraddr' 1701 for passing to bootargs (like Linux's netconsole option) 1702 1703- Gateway IP address: 1704 CONFIG_GATEWAYIP 1705 1706 Defines a default value for the IP address of the 1707 default router where packets to other networks are 1708 sent to. 1709 (Environment variable "gatewayip") 1710 1711- Subnet mask: 1712 CONFIG_NETMASK 1713 1714 Defines a default value for the subnet mask (or 1715 routing prefix) which is used to determine if an IP 1716 address belongs to the local subnet or needs to be 1717 forwarded through a router. 1718 (Environment variable "netmask") 1719 1720- Multicast TFTP Mode: 1721 CONFIG_MCAST_TFTP 1722 1723 Defines whether you want to support multicast TFTP as per 1724 rfc-2090; for example to work with atftp. Lets lots of targets 1725 tftp down the same boot image concurrently. Note: the Ethernet 1726 driver in use must provide a function: mcast() to join/leave a 1727 multicast group. 1728 1729- BOOTP Recovery Mode: 1730 CONFIG_BOOTP_RANDOM_DELAY 1731 1732 If you have many targets in a network that try to 1733 boot using BOOTP, you may want to avoid that all 1734 systems send out BOOTP requests at precisely the same 1735 moment (which would happen for instance at recovery 1736 from a power failure, when all systems will try to 1737 boot, thus flooding the BOOTP server. Defining 1738 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1739 inserted before sending out BOOTP requests. The 1740 following delays are inserted then: 1741 1742 1st BOOTP request: delay 0 ... 1 sec 1743 2nd BOOTP request: delay 0 ... 2 sec 1744 3rd BOOTP request: delay 0 ... 4 sec 1745 4th and following 1746 BOOTP requests: delay 0 ... 8 sec 1747 1748- DHCP Advanced Options: 1749 You can fine tune the DHCP functionality by defining 1750 CONFIG_BOOTP_* symbols: 1751 1752 CONFIG_BOOTP_SUBNETMASK 1753 CONFIG_BOOTP_GATEWAY 1754 CONFIG_BOOTP_HOSTNAME 1755 CONFIG_BOOTP_NISDOMAIN 1756 CONFIG_BOOTP_BOOTPATH 1757 CONFIG_BOOTP_BOOTFILESIZE 1758 CONFIG_BOOTP_DNS 1759 CONFIG_BOOTP_DNS2 1760 CONFIG_BOOTP_SEND_HOSTNAME 1761 CONFIG_BOOTP_NTPSERVER 1762 CONFIG_BOOTP_TIMEOFFSET 1763 CONFIG_BOOTP_VENDOREX 1764 CONFIG_BOOTP_MAY_FAIL 1765 1766 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1767 environment variable, not the BOOTP server. 1768 1769 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1770 after the configured retry count, the call will fail 1771 instead of starting over. This can be used to fail over 1772 to Link-local IP address configuration if the DHCP server 1773 is not available. 1774 1775 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1776 serverip from a DHCP server, it is possible that more 1777 than one DNS serverip is offered to the client. 1778 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1779 serverip will be stored in the additional environment 1780 variable "dnsip2". The first DNS serverip is always 1781 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1782 is defined. 1783 1784 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1785 to do a dynamic update of a DNS server. To do this, they 1786 need the hostname of the DHCP requester. 1787 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1788 of the "hostname" environment variable is passed as 1789 option 12 to the DHCP server. 1790 1791 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1792 1793 A 32bit value in microseconds for a delay between 1794 receiving a "DHCP Offer" and sending the "DHCP Request". 1795 This fixes a problem with certain DHCP servers that don't 1796 respond 100% of the time to a "DHCP request". E.g. On an 1797 AT91RM9200 processor running at 180MHz, this delay needed 1798 to be *at least* 15,000 usec before a Windows Server 2003 1799 DHCP server would reply 100% of the time. I recommend at 1800 least 50,000 usec to be safe. The alternative is to hope 1801 that one of the retries will be successful but note that 1802 the DHCP timeout and retry process takes a longer than 1803 this delay. 1804 1805 - Link-local IP address negotiation: 1806 Negotiate with other link-local clients on the local network 1807 for an address that doesn't require explicit configuration. 1808 This is especially useful if a DHCP server cannot be guaranteed 1809 to exist in all environments that the device must operate. 1810 1811 See doc/README.link-local for more information. 1812 1813 - CDP Options: 1814 CONFIG_CDP_DEVICE_ID 1815 1816 The device id used in CDP trigger frames. 1817 1818 CONFIG_CDP_DEVICE_ID_PREFIX 1819 1820 A two character string which is prefixed to the MAC address 1821 of the device. 1822 1823 CONFIG_CDP_PORT_ID 1824 1825 A printf format string which contains the ascii name of 1826 the port. Normally is set to "eth%d" which sets 1827 eth0 for the first Ethernet, eth1 for the second etc. 1828 1829 CONFIG_CDP_CAPABILITIES 1830 1831 A 32bit integer which indicates the device capabilities; 1832 0x00000010 for a normal host which does not forwards. 1833 1834 CONFIG_CDP_VERSION 1835 1836 An ascii string containing the version of the software. 1837 1838 CONFIG_CDP_PLATFORM 1839 1840 An ascii string containing the name of the platform. 1841 1842 CONFIG_CDP_TRIGGER 1843 1844 A 32bit integer sent on the trigger. 1845 1846 CONFIG_CDP_POWER_CONSUMPTION 1847 1848 A 16bit integer containing the power consumption of the 1849 device in .1 of milliwatts. 1850 1851 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1852 1853 A byte containing the id of the VLAN. 1854 1855- Status LED: CONFIG_STATUS_LED 1856 1857 Several configurations allow to display the current 1858 status using a LED. For instance, the LED will blink 1859 fast while running U-Boot code, stop blinking as 1860 soon as a reply to a BOOTP request was received, and 1861 start blinking slow once the Linux kernel is running 1862 (supported by a status LED driver in the Linux 1863 kernel). Defining CONFIG_STATUS_LED enables this 1864 feature in U-Boot. 1865 1866- CAN Support: CONFIG_CAN_DRIVER 1867 1868 Defining CONFIG_CAN_DRIVER enables CAN driver support 1869 on those systems that support this (optional) 1870 feature, like the TQM8xxL modules. 1871 1872- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1873 1874 These enable I2C serial bus commands. Defining either of 1875 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1876 include the appropriate I2C driver for the selected CPU. 1877 1878 This will allow you to use i2c commands at the u-boot 1879 command line (as long as you set CONFIG_CMD_I2C in 1880 CONFIG_COMMANDS) and communicate with i2c based realtime 1881 clock chips. See common/cmd_i2c.c for a description of the 1882 command line interface. 1883 1884 CONFIG_HARD_I2C selects a hardware I2C controller. 1885 1886 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1887 bit-banging) driver instead of CPM or similar hardware 1888 support for I2C. 1889 1890 There are several other quantities that must also be 1891 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1892 1893 In both cases you will need to define CONFIG_SYS_I2C_SPEED 1894 to be the frequency (in Hz) at which you wish your i2c bus 1895 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 1896 the CPU's i2c node address). 1897 1898 Now, the u-boot i2c code for the mpc8xx 1899 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 1900 and so its address should therefore be cleared to 0 (See, 1901 eg, MPC823e User's Manual p.16-473). So, set 1902 CONFIG_SYS_I2C_SLAVE to 0. 1903 1904 CONFIG_SYS_I2C_INIT_MPC5XXX 1905 1906 When a board is reset during an i2c bus transfer 1907 chips might think that the current transfer is still 1908 in progress. Reset the slave devices by sending start 1909 commands until the slave device responds. 1910 1911 That's all that's required for CONFIG_HARD_I2C. 1912 1913 If you use the software i2c interface (CONFIG_SOFT_I2C) 1914 then the following macros need to be defined (examples are 1915 from include/configs/lwmon.h): 1916 1917 I2C_INIT 1918 1919 (Optional). Any commands necessary to enable the I2C 1920 controller or configure ports. 1921 1922 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1923 1924 I2C_PORT 1925 1926 (Only for MPC8260 CPU). The I/O port to use (the code 1927 assumes both bits are on the same port). Valid values 1928 are 0..3 for ports A..D. 1929 1930 I2C_ACTIVE 1931 1932 The code necessary to make the I2C data line active 1933 (driven). If the data line is open collector, this 1934 define can be null. 1935 1936 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1937 1938 I2C_TRISTATE 1939 1940 The code necessary to make the I2C data line tri-stated 1941 (inactive). If the data line is open collector, this 1942 define can be null. 1943 1944 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1945 1946 I2C_READ 1947 1948 Code that returns true if the I2C data line is high, 1949 false if it is low. 1950 1951 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1952 1953 I2C_SDA(bit) 1954 1955 If <bit> is true, sets the I2C data line high. If it 1956 is false, it clears it (low). 1957 1958 eg: #define I2C_SDA(bit) \ 1959 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1960 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1961 1962 I2C_SCL(bit) 1963 1964 If <bit> is true, sets the I2C clock line high. If it 1965 is false, it clears it (low). 1966 1967 eg: #define I2C_SCL(bit) \ 1968 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1969 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1970 1971 I2C_DELAY 1972 1973 This delay is invoked four times per clock cycle so this 1974 controls the rate of data transfer. The data rate thus 1975 is 1 / (I2C_DELAY * 4). Often defined to be something 1976 like: 1977 1978 #define I2C_DELAY udelay(2) 1979 1980 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 1981 1982 If your arch supports the generic GPIO framework (asm/gpio.h), 1983 then you may alternatively define the two GPIOs that are to be 1984 used as SCL / SDA. Any of the previous I2C_xxx macros will 1985 have GPIO-based defaults assigned to them as appropriate. 1986 1987 You should define these to the GPIO value as given directly to 1988 the generic GPIO functions. 1989 1990 CONFIG_SYS_I2C_INIT_BOARD 1991 1992 When a board is reset during an i2c bus transfer 1993 chips might think that the current transfer is still 1994 in progress. On some boards it is possible to access 1995 the i2c SCLK line directly, either by using the 1996 processor pin as a GPIO or by having a second pin 1997 connected to the bus. If this option is defined a 1998 custom i2c_init_board() routine in boards/xxx/board.c 1999 is run early in the boot sequence. 2000 2001 CONFIG_SYS_I2C_BOARD_LATE_INIT 2002 2003 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 2004 defined a custom i2c_board_late_init() routine in 2005 boards/xxx/board.c is run AFTER the operations in i2c_init() 2006 is completed. This callpoint can be used to unreset i2c bus 2007 using CPU i2c controller register accesses for CPUs whose i2c 2008 controller provide such a method. It is called at the end of 2009 i2c_init() to allow i2c_init operations to setup the i2c bus 2010 controller on the CPU (e.g. setting bus speed & slave address). 2011 2012 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 2013 2014 This option enables configuration of bi_iic_fast[] flags 2015 in u-boot bd_info structure based on u-boot environment 2016 variable "i2cfast". (see also i2cfast) 2017 2018 CONFIG_I2C_MULTI_BUS 2019 2020 This option allows the use of multiple I2C buses, each of which 2021 must have a controller. At any point in time, only one bus is 2022 active. To switch to a different bus, use the 'i2c dev' command. 2023 Note that bus numbering is zero-based. 2024 2025 CONFIG_SYS_I2C_NOPROBES 2026 2027 This option specifies a list of I2C devices that will be skipped 2028 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2029 is set, specify a list of bus-device pairs. Otherwise, specify 2030 a 1D array of device addresses 2031 2032 e.g. 2033 #undef CONFIG_I2C_MULTI_BUS 2034 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2035 2036 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2037 2038 #define CONFIG_I2C_MULTI_BUS 2039 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2040 2041 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2042 2043 CONFIG_SYS_SPD_BUS_NUM 2044 2045 If defined, then this indicates the I2C bus number for DDR SPD. 2046 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2047 2048 CONFIG_SYS_RTC_BUS_NUM 2049 2050 If defined, then this indicates the I2C bus number for the RTC. 2051 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2052 2053 CONFIG_SYS_DTT_BUS_NUM 2054 2055 If defined, then this indicates the I2C bus number for the DTT. 2056 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2057 2058 CONFIG_SYS_I2C_DTT_ADDR: 2059 2060 If defined, specifies the I2C address of the DTT device. 2061 If not defined, then U-Boot uses predefined value for 2062 specified DTT device. 2063 2064 CONFIG_FSL_I2C 2065 2066 Define this option if you want to use Freescale's I2C driver in 2067 drivers/i2c/fsl_i2c.c. 2068 2069 CONFIG_I2C_MUX 2070 2071 Define this option if you have I2C devices reached over 1 .. n 2072 I2C Muxes like the pca9544a. This option addes a new I2C 2073 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a 2074 new I2C Bus to the existing I2C Busses. If you select the 2075 new Bus with "i2c dev", u-bbot sends first the commandos for 2076 the muxes to activate this new "bus". 2077 2078 CONFIG_I2C_MULTI_BUS must be also defined, to use this 2079 feature! 2080 2081 Example: 2082 Adding a new I2C Bus reached over 2 pca9544a muxes 2083 The First mux with address 70 and channel 6 2084 The Second mux with address 71 and channel 4 2085 2086 => i2c bus pca9544a:70:6:pca9544a:71:4 2087 2088 Use the "i2c bus" command without parameter, to get a list 2089 of I2C Busses with muxes: 2090 2091 => i2c bus 2092 Busses reached over muxes: 2093 Bus ID: 2 2094 reached over Mux(es): 2095 pca9544a@70 ch: 4 2096 Bus ID: 3 2097 reached over Mux(es): 2098 pca9544a@70 ch: 6 2099 pca9544a@71 ch: 4 2100 => 2101 2102 If you now switch to the new I2C Bus 3 with "i2c dev 3" 2103 u-boot first sends the command to the mux@70 to enable 2104 channel 6, and then the command to the mux@71 to enable 2105 the channel 4. 2106 2107 After that, you can use the "normal" i2c commands as 2108 usual to communicate with your I2C devices behind 2109 the 2 muxes. 2110 2111 This option is actually implemented for the bitbanging 2112 algorithm in common/soft_i2c.c and for the Hardware I2C 2113 Bus on the MPC8260. But it should be not so difficult 2114 to add this option to other architectures. 2115 2116 CONFIG_SOFT_I2C_READ_REPEATED_START 2117 2118 defining this will force the i2c_read() function in 2119 the soft_i2c driver to perform an I2C repeated start 2120 between writing the address pointer and reading the 2121 data. If this define is omitted the default behaviour 2122 of doing a stop-start sequence will be used. Most I2C 2123 devices can use either method, but some require one or 2124 the other. 2125 2126- SPI Support: CONFIG_SPI 2127 2128 Enables SPI driver (so far only tested with 2129 SPI EEPROM, also an instance works with Crystal A/D and 2130 D/As on the SACSng board) 2131 2132 CONFIG_SH_SPI 2133 2134 Enables the driver for SPI controller on SuperH. Currently 2135 only SH7757 is supported. 2136 2137 CONFIG_SPI_X 2138 2139 Enables extended (16-bit) SPI EEPROM addressing. 2140 (symmetrical to CONFIG_I2C_X) 2141 2142 CONFIG_SOFT_SPI 2143 2144 Enables a software (bit-bang) SPI driver rather than 2145 using hardware support. This is a general purpose 2146 driver that only requires three general I/O port pins 2147 (two outputs, one input) to function. If this is 2148 defined, the board configuration must define several 2149 SPI configuration items (port pins to use, etc). For 2150 an example, see include/configs/sacsng.h. 2151 2152 CONFIG_HARD_SPI 2153 2154 Enables a hardware SPI driver for general-purpose reads 2155 and writes. As with CONFIG_SOFT_SPI, the board configuration 2156 must define a list of chip-select function pointers. 2157 Currently supported on some MPC8xxx processors. For an 2158 example, see include/configs/mpc8349emds.h. 2159 2160 CONFIG_MXC_SPI 2161 2162 Enables the driver for the SPI controllers on i.MX and MXC 2163 SoCs. Currently i.MX31/35/51 are supported. 2164 2165- FPGA Support: CONFIG_FPGA 2166 2167 Enables FPGA subsystem. 2168 2169 CONFIG_FPGA_<vendor> 2170 2171 Enables support for specific chip vendors. 2172 (ALTERA, XILINX) 2173 2174 CONFIG_FPGA_<family> 2175 2176 Enables support for FPGA family. 2177 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2178 2179 CONFIG_FPGA_COUNT 2180 2181 Specify the number of FPGA devices to support. 2182 2183 CONFIG_SYS_FPGA_PROG_FEEDBACK 2184 2185 Enable printing of hash marks during FPGA configuration. 2186 2187 CONFIG_SYS_FPGA_CHECK_BUSY 2188 2189 Enable checks on FPGA configuration interface busy 2190 status by the configuration function. This option 2191 will require a board or device specific function to 2192 be written. 2193 2194 CONFIG_FPGA_DELAY 2195 2196 If defined, a function that provides delays in the FPGA 2197 configuration driver. 2198 2199 CONFIG_SYS_FPGA_CHECK_CTRLC 2200 Allow Control-C to interrupt FPGA configuration 2201 2202 CONFIG_SYS_FPGA_CHECK_ERROR 2203 2204 Check for configuration errors during FPGA bitfile 2205 loading. For example, abort during Virtex II 2206 configuration if the INIT_B line goes low (which 2207 indicated a CRC error). 2208 2209 CONFIG_SYS_FPGA_WAIT_INIT 2210 2211 Maximum time to wait for the INIT_B line to deassert 2212 after PROB_B has been deasserted during a Virtex II 2213 FPGA configuration sequence. The default time is 500 2214 ms. 2215 2216 CONFIG_SYS_FPGA_WAIT_BUSY 2217 2218 Maximum time to wait for BUSY to deassert during 2219 Virtex II FPGA configuration. The default is 5 ms. 2220 2221 CONFIG_SYS_FPGA_WAIT_CONFIG 2222 2223 Time to wait after FPGA configuration. The default is 2224 200 ms. 2225 2226- Configuration Management: 2227 CONFIG_IDENT_STRING 2228 2229 If defined, this string will be added to the U-Boot 2230 version information (U_BOOT_VERSION) 2231 2232- Vendor Parameter Protection: 2233 2234 U-Boot considers the values of the environment 2235 variables "serial#" (Board Serial Number) and 2236 "ethaddr" (Ethernet Address) to be parameters that 2237 are set once by the board vendor / manufacturer, and 2238 protects these variables from casual modification by 2239 the user. Once set, these variables are read-only, 2240 and write or delete attempts are rejected. You can 2241 change this behaviour: 2242 2243 If CONFIG_ENV_OVERWRITE is #defined in your config 2244 file, the write protection for vendor parameters is 2245 completely disabled. Anybody can change or delete 2246 these parameters. 2247 2248 Alternatively, if you #define _both_ CONFIG_ETHADDR 2249 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2250 Ethernet address is installed in the environment, 2251 which can be changed exactly ONCE by the user. [The 2252 serial# is unaffected by this, i. e. it remains 2253 read-only.] 2254 2255 The same can be accomplished in a more flexible way 2256 for any variable by configuring the type of access 2257 to allow for those variables in the ".flags" variable 2258 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2259 2260- Protected RAM: 2261 CONFIG_PRAM 2262 2263 Define this variable to enable the reservation of 2264 "protected RAM", i. e. RAM which is not overwritten 2265 by U-Boot. Define CONFIG_PRAM to hold the number of 2266 kB you want to reserve for pRAM. You can overwrite 2267 this default value by defining an environment 2268 variable "pram" to the number of kB you want to 2269 reserve. Note that the board info structure will 2270 still show the full amount of RAM. If pRAM is 2271 reserved, a new environment variable "mem" will 2272 automatically be defined to hold the amount of 2273 remaining RAM in a form that can be passed as boot 2274 argument to Linux, for instance like that: 2275 2276 setenv bootargs ... mem=\${mem} 2277 saveenv 2278 2279 This way you can tell Linux not to use this memory, 2280 either, which results in a memory region that will 2281 not be affected by reboots. 2282 2283 *WARNING* If your board configuration uses automatic 2284 detection of the RAM size, you must make sure that 2285 this memory test is non-destructive. So far, the 2286 following board configurations are known to be 2287 "pRAM-clean": 2288 2289 IVMS8, IVML24, SPD8xx, TQM8xxL, 2290 HERMES, IP860, RPXlite, LWMON, 2291 FLAGADM, TQM8260 2292 2293- Access to physical memory region (> 4GB) 2294 Some basic support is provided for operations on memory not 2295 normally accessible to U-Boot - e.g. some architectures 2296 support access to more than 4GB of memory on 32-bit 2297 machines using physical address extension or similar. 2298 Define CONFIG_PHYSMEM to access this basic support, which 2299 currently only supports clearing the memory. 2300 2301- Error Recovery: 2302 CONFIG_PANIC_HANG 2303 2304 Define this variable to stop the system in case of a 2305 fatal error, so that you have to reset it manually. 2306 This is probably NOT a good idea for an embedded 2307 system where you want the system to reboot 2308 automatically as fast as possible, but it may be 2309 useful during development since you can try to debug 2310 the conditions that lead to the situation. 2311 2312 CONFIG_NET_RETRY_COUNT 2313 2314 This variable defines the number of retries for 2315 network operations like ARP, RARP, TFTP, or BOOTP 2316 before giving up the operation. If not defined, a 2317 default value of 5 is used. 2318 2319 CONFIG_ARP_TIMEOUT 2320 2321 Timeout waiting for an ARP reply in milliseconds. 2322 2323 CONFIG_NFS_TIMEOUT 2324 2325 Timeout in milliseconds used in NFS protocol. 2326 If you encounter "ERROR: Cannot umount" in nfs command, 2327 try longer timeout such as 2328 #define CONFIG_NFS_TIMEOUT 10000UL 2329 2330- Command Interpreter: 2331 CONFIG_AUTO_COMPLETE 2332 2333 Enable auto completion of commands using TAB. 2334 2335 Note that this feature has NOT been implemented yet 2336 for the "hush" shell. 2337 2338 2339 CONFIG_SYS_HUSH_PARSER 2340 2341 Define this variable to enable the "hush" shell (from 2342 Busybox) as command line interpreter, thus enabling 2343 powerful command line syntax like 2344 if...then...else...fi conditionals or `&&' and '||' 2345 constructs ("shell scripts"). 2346 2347 If undefined, you get the old, much simpler behaviour 2348 with a somewhat smaller memory footprint. 2349 2350 2351 CONFIG_SYS_PROMPT_HUSH_PS2 2352 2353 This defines the secondary prompt string, which is 2354 printed when the command interpreter needs more input 2355 to complete a command. Usually "> ". 2356 2357 Note: 2358 2359 In the current implementation, the local variables 2360 space and global environment variables space are 2361 separated. Local variables are those you define by 2362 simply typing `name=value'. To access a local 2363 variable later on, you have write `$name' or 2364 `${name}'; to execute the contents of a variable 2365 directly type `$name' at the command prompt. 2366 2367 Global environment variables are those you use 2368 setenv/printenv to work with. To run a command stored 2369 in such a variable, you need to use the run command, 2370 and you must not use the '$' sign to access them. 2371 2372 To store commands and special characters in a 2373 variable, please use double quotation marks 2374 surrounding the whole text of the variable, instead 2375 of the backslashes before semicolons and special 2376 symbols. 2377 2378- Commandline Editing and History: 2379 CONFIG_CMDLINE_EDITING 2380 2381 Enable editing and History functions for interactive 2382 commandline input operations 2383 2384- Default Environment: 2385 CONFIG_EXTRA_ENV_SETTINGS 2386 2387 Define this to contain any number of null terminated 2388 strings (variable = value pairs) that will be part of 2389 the default environment compiled into the boot image. 2390 2391 For example, place something like this in your 2392 board's config file: 2393 2394 #define CONFIG_EXTRA_ENV_SETTINGS \ 2395 "myvar1=value1\0" \ 2396 "myvar2=value2\0" 2397 2398 Warning: This method is based on knowledge about the 2399 internal format how the environment is stored by the 2400 U-Boot code. This is NOT an official, exported 2401 interface! Although it is unlikely that this format 2402 will change soon, there is no guarantee either. 2403 You better know what you are doing here. 2404 2405 Note: overly (ab)use of the default environment is 2406 discouraged. Make sure to check other ways to preset 2407 the environment like the "source" command or the 2408 boot command first. 2409 2410 CONFIG_ENV_VARS_UBOOT_CONFIG 2411 2412 Define this in order to add variables describing the 2413 U-Boot build configuration to the default environment. 2414 These will be named arch, cpu, board, vendor, and soc. 2415 2416 Enabling this option will cause the following to be defined: 2417 2418 - CONFIG_SYS_ARCH 2419 - CONFIG_SYS_CPU 2420 - CONFIG_SYS_BOARD 2421 - CONFIG_SYS_VENDOR 2422 - CONFIG_SYS_SOC 2423 2424 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2425 2426 Define this in order to add variables describing certain 2427 run-time determined information about the hardware to the 2428 environment. These will be named board_name, board_rev. 2429 2430 CONFIG_DELAY_ENVIRONMENT 2431 2432 Normally the environment is loaded when the board is 2433 intialised so that it is available to U-Boot. This inhibits 2434 that so that the environment is not available until 2435 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2436 this is instead controlled by the value of 2437 /config/load-environment. 2438 2439- DataFlash Support: 2440 CONFIG_HAS_DATAFLASH 2441 2442 Defining this option enables DataFlash features and 2443 allows to read/write in Dataflash via the standard 2444 commands cp, md... 2445 2446- Serial Flash support 2447 CONFIG_CMD_SF 2448 2449 Defining this option enables SPI flash commands 2450 'sf probe/read/write/erase/update'. 2451 2452 Usage requires an initial 'probe' to define the serial 2453 flash parameters, followed by read/write/erase/update 2454 commands. 2455 2456 The following defaults may be provided by the platform 2457 to handle the common case when only a single serial 2458 flash is present on the system. 2459 2460 CONFIG_SF_DEFAULT_BUS Bus identifier 2461 CONFIG_SF_DEFAULT_CS Chip-select 2462 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2463 CONFIG_SF_DEFAULT_SPEED in Hz 2464 2465 CONFIG_CMD_SF_TEST 2466 2467 Define this option to include a destructive SPI flash 2468 test ('sf test'). 2469 2470- SystemACE Support: 2471 CONFIG_SYSTEMACE 2472 2473 Adding this option adds support for Xilinx SystemACE 2474 chips attached via some sort of local bus. The address 2475 of the chip must also be defined in the 2476 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2477 2478 #define CONFIG_SYSTEMACE 2479 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2480 2481 When SystemACE support is added, the "ace" device type 2482 becomes available to the fat commands, i.e. fatls. 2483 2484- TFTP Fixed UDP Port: 2485 CONFIG_TFTP_PORT 2486 2487 If this is defined, the environment variable tftpsrcp 2488 is used to supply the TFTP UDP source port value. 2489 If tftpsrcp isn't defined, the normal pseudo-random port 2490 number generator is used. 2491 2492 Also, the environment variable tftpdstp is used to supply 2493 the TFTP UDP destination port value. If tftpdstp isn't 2494 defined, the normal port 69 is used. 2495 2496 The purpose for tftpsrcp is to allow a TFTP server to 2497 blindly start the TFTP transfer using the pre-configured 2498 target IP address and UDP port. This has the effect of 2499 "punching through" the (Windows XP) firewall, allowing 2500 the remainder of the TFTP transfer to proceed normally. 2501 A better solution is to properly configure the firewall, 2502 but sometimes that is not allowed. 2503 2504- Hashing support: 2505 CONFIG_CMD_HASH 2506 2507 This enables a generic 'hash' command which can produce 2508 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2509 2510 CONFIG_HASH_VERIFY 2511 2512 Enable the hash verify command (hash -v). This adds to code 2513 size a little. 2514 2515 CONFIG_SHA1 - support SHA1 hashing 2516 CONFIG_SHA256 - support SHA256 hashing 2517 2518 Note: There is also a sha1sum command, which should perhaps 2519 be deprecated in favour of 'hash sha1'. 2520 2521- Show boot progress: 2522 CONFIG_SHOW_BOOT_PROGRESS 2523 2524 Defining this option allows to add some board- 2525 specific code (calling a user-provided function 2526 "show_boot_progress(int)") that enables you to show 2527 the system's boot progress on some display (for 2528 example, some LED's) on your board. At the moment, 2529 the following checkpoints are implemented: 2530 2531- Detailed boot stage timing 2532 CONFIG_BOOTSTAGE 2533 Define this option to get detailed timing of each stage 2534 of the boot process. 2535 2536 CONFIG_BOOTSTAGE_USER_COUNT 2537 This is the number of available user bootstage records. 2538 Each time you call bootstage_mark(BOOTSTAGE_ID_ALLOC, ...) 2539 a new ID will be allocated from this stash. If you exceed 2540 the limit, recording will stop. 2541 2542 CONFIG_BOOTSTAGE_REPORT 2543 Define this to print a report before boot, similar to this: 2544 2545 Timer summary in microseconds: 2546 Mark Elapsed Stage 2547 0 0 reset 2548 3,575,678 3,575,678 board_init_f start 2549 3,575,695 17 arch_cpu_init A9 2550 3,575,777 82 arch_cpu_init done 2551 3,659,598 83,821 board_init_r start 2552 3,910,375 250,777 main_loop 2553 29,916,167 26,005,792 bootm_start 2554 30,361,327 445,160 start_kernel 2555 2556 CONFIG_CMD_BOOTSTAGE 2557 Add a 'bootstage' command which supports printing a report 2558 and un/stashing of bootstage data. 2559 2560 CONFIG_BOOTSTAGE_FDT 2561 Stash the bootstage information in the FDT. A root 'bootstage' 2562 node is created with each bootstage id as a child. Each child 2563 has a 'name' property and either 'mark' containing the 2564 mark time in microsecond, or 'accum' containing the 2565 accumulated time for that bootstage id in microseconds. 2566 For example: 2567 2568 bootstage { 2569 154 { 2570 name = "board_init_f"; 2571 mark = <3575678>; 2572 }; 2573 170 { 2574 name = "lcd"; 2575 accum = <33482>; 2576 }; 2577 }; 2578 2579 Code in the Linux kernel can find this in /proc/devicetree. 2580 2581Legacy uImage format: 2582 2583 Arg Where When 2584 1 common/cmd_bootm.c before attempting to boot an image 2585 -1 common/cmd_bootm.c Image header has bad magic number 2586 2 common/cmd_bootm.c Image header has correct magic number 2587 -2 common/cmd_bootm.c Image header has bad checksum 2588 3 common/cmd_bootm.c Image header has correct checksum 2589 -3 common/cmd_bootm.c Image data has bad checksum 2590 4 common/cmd_bootm.c Image data has correct checksum 2591 -4 common/cmd_bootm.c Image is for unsupported architecture 2592 5 common/cmd_bootm.c Architecture check OK 2593 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2594 6 common/cmd_bootm.c Image Type check OK 2595 -6 common/cmd_bootm.c gunzip uncompression error 2596 -7 common/cmd_bootm.c Unimplemented compression type 2597 7 common/cmd_bootm.c Uncompression OK 2598 8 common/cmd_bootm.c No uncompress/copy overwrite error 2599 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2600 2601 9 common/image.c Start initial ramdisk verification 2602 -10 common/image.c Ramdisk header has bad magic number 2603 -11 common/image.c Ramdisk header has bad checksum 2604 10 common/image.c Ramdisk header is OK 2605 -12 common/image.c Ramdisk data has bad checksum 2606 11 common/image.c Ramdisk data has correct checksum 2607 12 common/image.c Ramdisk verification complete, start loading 2608 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2609 13 common/image.c Start multifile image verification 2610 14 common/image.c No initial ramdisk, no multifile, continue. 2611 2612 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2613 2614 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2615 -31 post/post.c POST test failed, detected by post_output_backlog() 2616 -32 post/post.c POST test failed, detected by post_run_single() 2617 2618 34 common/cmd_doc.c before loading a Image from a DOC device 2619 -35 common/cmd_doc.c Bad usage of "doc" command 2620 35 common/cmd_doc.c correct usage of "doc" command 2621 -36 common/cmd_doc.c No boot device 2622 36 common/cmd_doc.c correct boot device 2623 -37 common/cmd_doc.c Unknown Chip ID on boot device 2624 37 common/cmd_doc.c correct chip ID found, device available 2625 -38 common/cmd_doc.c Read Error on boot device 2626 38 common/cmd_doc.c reading Image header from DOC device OK 2627 -39 common/cmd_doc.c Image header has bad magic number 2628 39 common/cmd_doc.c Image header has correct magic number 2629 -40 common/cmd_doc.c Error reading Image from DOC device 2630 40 common/cmd_doc.c Image header has correct magic number 2631 41 common/cmd_ide.c before loading a Image from a IDE device 2632 -42 common/cmd_ide.c Bad usage of "ide" command 2633 42 common/cmd_ide.c correct usage of "ide" command 2634 -43 common/cmd_ide.c No boot device 2635 43 common/cmd_ide.c boot device found 2636 -44 common/cmd_ide.c Device not available 2637 44 common/cmd_ide.c Device available 2638 -45 common/cmd_ide.c wrong partition selected 2639 45 common/cmd_ide.c partition selected 2640 -46 common/cmd_ide.c Unknown partition table 2641 46 common/cmd_ide.c valid partition table found 2642 -47 common/cmd_ide.c Invalid partition type 2643 47 common/cmd_ide.c correct partition type 2644 -48 common/cmd_ide.c Error reading Image Header on boot device 2645 48 common/cmd_ide.c reading Image Header from IDE device OK 2646 -49 common/cmd_ide.c Image header has bad magic number 2647 49 common/cmd_ide.c Image header has correct magic number 2648 -50 common/cmd_ide.c Image header has bad checksum 2649 50 common/cmd_ide.c Image header has correct checksum 2650 -51 common/cmd_ide.c Error reading Image from IDE device 2651 51 common/cmd_ide.c reading Image from IDE device OK 2652 52 common/cmd_nand.c before loading a Image from a NAND device 2653 -53 common/cmd_nand.c Bad usage of "nand" command 2654 53 common/cmd_nand.c correct usage of "nand" command 2655 -54 common/cmd_nand.c No boot device 2656 54 common/cmd_nand.c boot device found 2657 -55 common/cmd_nand.c Unknown Chip ID on boot device 2658 55 common/cmd_nand.c correct chip ID found, device available 2659 -56 common/cmd_nand.c Error reading Image Header on boot device 2660 56 common/cmd_nand.c reading Image Header from NAND device OK 2661 -57 common/cmd_nand.c Image header has bad magic number 2662 57 common/cmd_nand.c Image header has correct magic number 2663 -58 common/cmd_nand.c Error reading Image from NAND device 2664 58 common/cmd_nand.c reading Image from NAND device OK 2665 2666 -60 common/env_common.c Environment has a bad CRC, using default 2667 2668 64 net/eth.c starting with Ethernet configuration. 2669 -64 net/eth.c no Ethernet found. 2670 65 net/eth.c Ethernet found. 2671 2672 -80 common/cmd_net.c usage wrong 2673 80 common/cmd_net.c before calling NetLoop() 2674 -81 common/cmd_net.c some error in NetLoop() occurred 2675 81 common/cmd_net.c NetLoop() back without error 2676 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2677 82 common/cmd_net.c trying automatic boot 2678 83 common/cmd_net.c running "source" command 2679 -83 common/cmd_net.c some error in automatic boot or "source" command 2680 84 common/cmd_net.c end without errors 2681 2682FIT uImage format: 2683 2684 Arg Where When 2685 100 common/cmd_bootm.c Kernel FIT Image has correct format 2686 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2687 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2688 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2689 102 common/cmd_bootm.c Kernel unit name specified 2690 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2691 103 common/cmd_bootm.c Found configuration node 2692 104 common/cmd_bootm.c Got kernel subimage node offset 2693 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2694 105 common/cmd_bootm.c Kernel subimage hash verification OK 2695 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2696 106 common/cmd_bootm.c Architecture check OK 2697 -106 common/cmd_bootm.c Kernel subimage has wrong type 2698 107 common/cmd_bootm.c Kernel subimage type OK 2699 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2700 108 common/cmd_bootm.c Got kernel subimage data/size 2701 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2702 -109 common/cmd_bootm.c Can't get kernel subimage type 2703 -110 common/cmd_bootm.c Can't get kernel subimage comp 2704 -111 common/cmd_bootm.c Can't get kernel subimage os 2705 -112 common/cmd_bootm.c Can't get kernel subimage load address 2706 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2707 2708 120 common/image.c Start initial ramdisk verification 2709 -120 common/image.c Ramdisk FIT image has incorrect format 2710 121 common/image.c Ramdisk FIT image has correct format 2711 122 common/image.c No ramdisk subimage unit name, using configuration 2712 -122 common/image.c Can't get configuration for ramdisk subimage 2713 123 common/image.c Ramdisk unit name specified 2714 -124 common/image.c Can't get ramdisk subimage node offset 2715 125 common/image.c Got ramdisk subimage node offset 2716 -125 common/image.c Ramdisk subimage hash verification failed 2717 126 common/image.c Ramdisk subimage hash verification OK 2718 -126 common/image.c Ramdisk subimage for unsupported architecture 2719 127 common/image.c Architecture check OK 2720 -127 common/image.c Can't get ramdisk subimage data/size 2721 128 common/image.c Got ramdisk subimage data/size 2722 129 common/image.c Can't get ramdisk load address 2723 -129 common/image.c Got ramdisk load address 2724 2725 -130 common/cmd_doc.c Incorrect FIT image format 2726 131 common/cmd_doc.c FIT image format OK 2727 2728 -140 common/cmd_ide.c Incorrect FIT image format 2729 141 common/cmd_ide.c FIT image format OK 2730 2731 -150 common/cmd_nand.c Incorrect FIT image format 2732 151 common/cmd_nand.c FIT image format OK 2733 2734- FIT image support: 2735 CONFIG_FIT 2736 Enable support for the FIT uImage format. 2737 2738 CONFIG_FIT_BEST_MATCH 2739 When no configuration is explicitly selected, default to the 2740 one whose fdt's compatibility field best matches that of 2741 U-Boot itself. A match is considered "best" if it matches the 2742 most specific compatibility entry of U-Boot's fdt's root node. 2743 The order of entries in the configuration's fdt is ignored. 2744 2745- Standalone program support: 2746 CONFIG_STANDALONE_LOAD_ADDR 2747 2748 This option defines a board specific value for the 2749 address where standalone program gets loaded, thus 2750 overwriting the architecture dependent default 2751 settings. 2752 2753- Frame Buffer Address: 2754 CONFIG_FB_ADDR 2755 2756 Define CONFIG_FB_ADDR if you want to use specific 2757 address for frame buffer. This is typically the case 2758 when using a graphics controller has separate video 2759 memory. U-Boot will then place the frame buffer at 2760 the given address instead of dynamically reserving it 2761 in system RAM by calling lcd_setmem(), which grabs 2762 the memory for the frame buffer depending on the 2763 configured panel size. 2764 2765 Please see board_init_f function. 2766 2767- Automatic software updates via TFTP server 2768 CONFIG_UPDATE_TFTP 2769 CONFIG_UPDATE_TFTP_CNT_MAX 2770 CONFIG_UPDATE_TFTP_MSEC_MAX 2771 2772 These options enable and control the auto-update feature; 2773 for a more detailed description refer to doc/README.update. 2774 2775- MTD Support (mtdparts command, UBI support) 2776 CONFIG_MTD_DEVICE 2777 2778 Adds the MTD device infrastructure from the Linux kernel. 2779 Needed for mtdparts command support. 2780 2781 CONFIG_MTD_PARTITIONS 2782 2783 Adds the MTD partitioning infrastructure from the Linux 2784 kernel. Needed for UBI support. 2785 2786- SPL framework 2787 CONFIG_SPL 2788 Enable building of SPL globally. 2789 2790 CONFIG_SPL_LDSCRIPT 2791 LDSCRIPT for linking the SPL binary. 2792 2793 CONFIG_SPL_MAX_SIZE 2794 Maximum binary size (text, data and rodata) of the SPL binary. 2795 2796 CONFIG_SPL_TEXT_BASE 2797 TEXT_BASE for linking the SPL binary. 2798 2799 CONFIG_SPL_RELOC_TEXT_BASE 2800 Address to relocate to. If unspecified, this is equal to 2801 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 2802 2803 CONFIG_SPL_BSS_START_ADDR 2804 Link address for the BSS within the SPL binary. 2805 2806 CONFIG_SPL_BSS_MAX_SIZE 2807 Maximum binary size of the BSS section of the SPL binary. 2808 2809 CONFIG_SPL_STACK 2810 Adress of the start of the stack SPL will use 2811 2812 CONFIG_SPL_RELOC_STACK 2813 Adress of the start of the stack SPL will use after 2814 relocation. If unspecified, this is equal to 2815 CONFIG_SPL_STACK. 2816 2817 CONFIG_SYS_SPL_MALLOC_START 2818 Starting address of the malloc pool used in SPL. 2819 2820 CONFIG_SYS_SPL_MALLOC_SIZE 2821 The size of the malloc pool used in SPL. 2822 2823 CONFIG_SPL_FRAMEWORK 2824 Enable the SPL framework under common/. This framework 2825 supports MMC, NAND and YMODEM loading of U-Boot and NAND 2826 NAND loading of the Linux Kernel. 2827 2828 CONFIG_SPL_DISPLAY_PRINT 2829 For ARM, enable an optional function to print more information 2830 about the running system. 2831 2832 CONFIG_SPL_INIT_MINIMAL 2833 Arch init code should be built for a very small image 2834 2835 CONFIG_SPL_LIBCOMMON_SUPPORT 2836 Support for common/libcommon.o in SPL binary 2837 2838 CONFIG_SPL_LIBDISK_SUPPORT 2839 Support for disk/libdisk.o in SPL binary 2840 2841 CONFIG_SPL_I2C_SUPPORT 2842 Support for drivers/i2c/libi2c.o in SPL binary 2843 2844 CONFIG_SPL_GPIO_SUPPORT 2845 Support for drivers/gpio/libgpio.o in SPL binary 2846 2847 CONFIG_SPL_MMC_SUPPORT 2848 Support for drivers/mmc/libmmc.o in SPL binary 2849 2850 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_SECTOR, 2851 CONFIG_SYS_U_BOOT_MAX_SIZE_SECTORS, 2852 CONFIG_SYS_MMC_SD_FAT_BOOT_PARTITION 2853 Address, size and partition on the MMC to load U-Boot from 2854 when the MMC is being used in raw mode. 2855 2856 CONFIG_SPL_FAT_SUPPORT 2857 Support for fs/fat/libfat.o in SPL binary 2858 2859 CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME 2860 Filename to read to load U-Boot when reading from FAT 2861 2862 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 2863 Set this for NAND SPL on PPC mpc83xx targets, so that 2864 start.S waits for the rest of the SPL to load before 2865 continuing (the hardware starts execution after just 2866 loading the first page rather than the full 4K). 2867 2868 CONFIG_SPL_NAND_BASE 2869 Include nand_base.c in the SPL. Requires 2870 CONFIG_SPL_NAND_DRIVERS. 2871 2872 CONFIG_SPL_NAND_DRIVERS 2873 SPL uses normal NAND drivers, not minimal drivers. 2874 2875 CONFIG_SPL_NAND_ECC 2876 Include standard software ECC in the SPL 2877 2878 CONFIG_SPL_NAND_SIMPLE 2879 Support for NAND boot using simple NAND drivers that 2880 expose the cmd_ctrl() interface. 2881 2882 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 2883 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 2884 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 2885 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 2886 CONFIG_SYS_NAND_ECCBYTES 2887 Defines the size and behavior of the NAND that SPL uses 2888 to read U-Boot 2889 2890 CONFIG_SYS_NAND_U_BOOT_OFFS 2891 Location in NAND to read U-Boot from 2892 2893 CONFIG_SYS_NAND_U_BOOT_DST 2894 Location in memory to load U-Boot to 2895 2896 CONFIG_SYS_NAND_U_BOOT_SIZE 2897 Size of image to load 2898 2899 CONFIG_SYS_NAND_U_BOOT_START 2900 Entry point in loaded image to jump to 2901 2902 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 2903 Define this if you need to first read the OOB and then the 2904 data. This is used for example on davinci plattforms. 2905 2906 CONFIG_SPL_OMAP3_ID_NAND 2907 Support for an OMAP3-specific set of functions to return the 2908 ID and MFR of the first attached NAND chip, if present. 2909 2910 CONFIG_SPL_SERIAL_SUPPORT 2911 Support for drivers/serial/libserial.o in SPL binary 2912 2913 CONFIG_SPL_SPI_FLASH_SUPPORT 2914 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 2915 2916 CONFIG_SPL_SPI_SUPPORT 2917 Support for drivers/spi/libspi.o in SPL binary 2918 2919 CONFIG_SPL_RAM_DEVICE 2920 Support for running image already present in ram, in SPL binary 2921 2922 CONFIG_SPL_LIBGENERIC_SUPPORT 2923 Support for lib/libgeneric.o in SPL binary 2924 2925 CONFIG_SPL_PAD_TO 2926 Linker address to which the SPL should be padded before 2927 appending the SPL payload. 2928 2929 CONFIG_SPL_TARGET 2930 Final target image containing SPL and payload. Some SPLs 2931 use an arch-specific makefile fragment instead, for 2932 example if more than one image needs to be produced. 2933 2934Modem Support: 2935-------------- 2936 2937[so far only for SMDK2400 boards] 2938 2939- Modem support enable: 2940 CONFIG_MODEM_SUPPORT 2941 2942- RTS/CTS Flow control enable: 2943 CONFIG_HWFLOW 2944 2945- Modem debug support: 2946 CONFIG_MODEM_SUPPORT_DEBUG 2947 2948 Enables debugging stuff (char screen[1024], dbg()) 2949 for modem support. Useful only with BDI2000. 2950 2951- Interrupt support (PPC): 2952 2953 There are common interrupt_init() and timer_interrupt() 2954 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 2955 for CPU specific initialization. interrupt_init_cpu() 2956 should set decrementer_count to appropriate value. If 2957 CPU resets decrementer automatically after interrupt 2958 (ppc4xx) it should set decrementer_count to zero. 2959 timer_interrupt() calls timer_interrupt_cpu() for CPU 2960 specific handling. If board has watchdog / status_led 2961 / other_activity_monitor it works automatically from 2962 general timer_interrupt(). 2963 2964- General: 2965 2966 In the target system modem support is enabled when a 2967 specific key (key combination) is pressed during 2968 power-on. Otherwise U-Boot will boot normally 2969 (autoboot). The key_pressed() function is called from 2970 board_init(). Currently key_pressed() is a dummy 2971 function, returning 1 and thus enabling modem 2972 initialization. 2973 2974 If there are no modem init strings in the 2975 environment, U-Boot proceed to autoboot; the 2976 previous output (banner, info printfs) will be 2977 suppressed, though. 2978 2979 See also: doc/README.Modem 2980 2981Board initialization settings: 2982------------------------------ 2983 2984During Initialization u-boot calls a number of board specific functions 2985to allow the preparation of board specific prerequisites, e.g. pin setup 2986before drivers are initialized. To enable these callbacks the 2987following configuration macros have to be defined. Currently this is 2988architecture specific, so please check arch/your_architecture/lib/board.c 2989typically in board_init_f() and board_init_r(). 2990 2991- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 2992- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 2993- CONFIG_BOARD_LATE_INIT: Call board_late_init() 2994- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 2995 2996Configuration Settings: 2997----------------------- 2998 2999- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3000 undefine this when you're short of memory. 3001 3002- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3003 width of the commands listed in the 'help' command output. 3004 3005- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3006 prompt for user input. 3007 3008- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3009 3010- CONFIG_SYS_PBSIZE: Buffer size for Console output 3011 3012- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3013 3014- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3015 the application (usually a Linux kernel) when it is 3016 booted 3017 3018- CONFIG_SYS_BAUDRATE_TABLE: 3019 List of legal baudrate settings for this board. 3020 3021- CONFIG_SYS_CONSOLE_INFO_QUIET 3022 Suppress display of console information at boot. 3023 3024- CONFIG_SYS_CONSOLE_IS_IN_ENV 3025 If the board specific function 3026 extern int overwrite_console (void); 3027 returns 1, the stdin, stderr and stdout are switched to the 3028 serial port, else the settings in the environment are used. 3029 3030- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 3031 Enable the call to overwrite_console(). 3032 3033- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 3034 Enable overwrite of previous console environment settings. 3035 3036- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3037 Begin and End addresses of the area used by the 3038 simple memory test. 3039 3040- CONFIG_SYS_ALT_MEMTEST: 3041 Enable an alternate, more extensive memory test. 3042 3043- CONFIG_SYS_MEMTEST_SCRATCH: 3044 Scratch address used by the alternate memory test 3045 You only need to set this if address zero isn't writeable 3046 3047- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 3048 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3049 this specified memory area will get subtracted from the top 3050 (end) of RAM and won't get "touched" at all by U-Boot. By 3051 fixing up gd->ram_size the Linux kernel should gets passed 3052 the now "corrected" memory size and won't touch it either. 3053 This should work for arch/ppc and arch/powerpc. Only Linux 3054 board ports in arch/powerpc with bootwrapper support that 3055 recalculate the memory size from the SDRAM controller setup 3056 will have to get fixed in Linux additionally. 3057 3058 This option can be used as a workaround for the 440EPx/GRx 3059 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3060 be touched. 3061 3062 WARNING: Please make sure that this value is a multiple of 3063 the Linux page size (normally 4k). If this is not the case, 3064 then the end address of the Linux memory will be located at a 3065 non page size aligned address and this could cause major 3066 problems. 3067 3068- CONFIG_SYS_LOADS_BAUD_CHANGE: 3069 Enable temporary baudrate change while serial download 3070 3071- CONFIG_SYS_SDRAM_BASE: 3072 Physical start address of SDRAM. _Must_ be 0 here. 3073 3074- CONFIG_SYS_MBIO_BASE: 3075 Physical start address of Motherboard I/O (if using a 3076 Cogent motherboard) 3077 3078- CONFIG_SYS_FLASH_BASE: 3079 Physical start address of Flash memory. 3080 3081- CONFIG_SYS_MONITOR_BASE: 3082 Physical start address of boot monitor code (set by 3083 make config files to be same as the text base address 3084 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3085 CONFIG_SYS_FLASH_BASE when booting from flash. 3086 3087- CONFIG_SYS_MONITOR_LEN: 3088 Size of memory reserved for monitor code, used to 3089 determine _at_compile_time_ (!) if the environment is 3090 embedded within the U-Boot image, or in a separate 3091 flash sector. 3092 3093- CONFIG_SYS_MALLOC_LEN: 3094 Size of DRAM reserved for malloc() use. 3095 3096- CONFIG_SYS_BOOTM_LEN: 3097 Normally compressed uImages are limited to an 3098 uncompressed size of 8 MBytes. If this is not enough, 3099 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3100 to adjust this setting to your needs. 3101 3102- CONFIG_SYS_BOOTMAPSZ: 3103 Maximum size of memory mapped by the startup code of 3104 the Linux kernel; all data that must be processed by 3105 the Linux kernel (bd_info, boot arguments, FDT blob if 3106 used) must be put below this limit, unless "bootm_low" 3107 enviroment variable is defined and non-zero. In such case 3108 all data for the Linux kernel must be between "bootm_low" 3109 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3110 variable "bootm_mapsize" will override the value of 3111 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3112 then the value in "bootm_size" will be used instead. 3113 3114- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3115 Enable initrd_high functionality. If defined then the 3116 initrd_high feature is enabled and the bootm ramdisk subcommand 3117 is enabled. 3118 3119- CONFIG_SYS_BOOT_GET_CMDLINE: 3120 Enables allocating and saving kernel cmdline in space between 3121 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3122 3123- CONFIG_SYS_BOOT_GET_KBD: 3124 Enables allocating and saving a kernel copy of the bd_info in 3125 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3126 3127- CONFIG_SYS_MAX_FLASH_BANKS: 3128 Max number of Flash memory banks 3129 3130- CONFIG_SYS_MAX_FLASH_SECT: 3131 Max number of sectors on a Flash chip 3132 3133- CONFIG_SYS_FLASH_ERASE_TOUT: 3134 Timeout for Flash erase operations (in ms) 3135 3136- CONFIG_SYS_FLASH_WRITE_TOUT: 3137 Timeout for Flash write operations (in ms) 3138 3139- CONFIG_SYS_FLASH_LOCK_TOUT 3140 Timeout for Flash set sector lock bit operation (in ms) 3141 3142- CONFIG_SYS_FLASH_UNLOCK_TOUT 3143 Timeout for Flash clear lock bits operation (in ms) 3144 3145- CONFIG_SYS_FLASH_PROTECTION 3146 If defined, hardware flash sectors protection is used 3147 instead of U-Boot software protection. 3148 3149- CONFIG_SYS_DIRECT_FLASH_TFTP: 3150 3151 Enable TFTP transfers directly to flash memory; 3152 without this option such a download has to be 3153 performed in two steps: (1) download to RAM, and (2) 3154 copy from RAM to flash. 3155 3156 The two-step approach is usually more reliable, since 3157 you can check if the download worked before you erase 3158 the flash, but in some situations (when system RAM is 3159 too limited to allow for a temporary copy of the 3160 downloaded image) this option may be very useful. 3161 3162- CONFIG_SYS_FLASH_CFI: 3163 Define if the flash driver uses extra elements in the 3164 common flash structure for storing flash geometry. 3165 3166- CONFIG_FLASH_CFI_DRIVER 3167 This option also enables the building of the cfi_flash driver 3168 in the drivers directory 3169 3170- CONFIG_FLASH_CFI_MTD 3171 This option enables the building of the cfi_mtd driver 3172 in the drivers directory. The driver exports CFI flash 3173 to the MTD layer. 3174 3175- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3176 Use buffered writes to flash. 3177 3178- CONFIG_FLASH_SPANSION_S29WS_N 3179 s29ws-n MirrorBit flash has non-standard addresses for buffered 3180 write commands. 3181 3182- CONFIG_SYS_FLASH_QUIET_TEST 3183 If this option is defined, the common CFI flash doesn't 3184 print it's warning upon not recognized FLASH banks. This 3185 is useful, if some of the configured banks are only 3186 optionally available. 3187 3188- CONFIG_FLASH_SHOW_PROGRESS 3189 If defined (must be an integer), print out countdown 3190 digits and dots. Recommended value: 45 (9..1) for 80 3191 column displays, 15 (3..1) for 40 column displays. 3192 3193- CONFIG_SYS_RX_ETH_BUFFER: 3194 Defines the number of Ethernet receive buffers. On some 3195 Ethernet controllers it is recommended to set this value 3196 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3197 buffers can be full shortly after enabling the interface 3198 on high Ethernet traffic. 3199 Defaults to 4 if not defined. 3200 3201- CONFIG_ENV_MAX_ENTRIES 3202 3203 Maximum number of entries in the hash table that is used 3204 internally to store the environment settings. The default 3205 setting is supposed to be generous and should work in most 3206 cases. This setting can be used to tune behaviour; see 3207 lib/hashtable.c for details. 3208 3209- CONFIG_ENV_FLAGS_LIST_DEFAULT 3210- CONFIG_ENV_FLAGS_LIST_STATIC 3211 Enable validation of the values given to enviroment variables when 3212 calling env set. Variables can be restricted to only decimal, 3213 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3214 the variables can also be restricted to IP address or MAC address. 3215 3216 The format of the list is: 3217 type_attribute = [s|d|x|b|i|m] 3218 access_atribute = [a|r|o|c] 3219 attributes = type_attribute[access_atribute] 3220 entry = variable_name[:attributes] 3221 list = entry[,list] 3222 3223 The type attributes are: 3224 s - String (default) 3225 d - Decimal 3226 x - Hexadecimal 3227 b - Boolean ([1yYtT|0nNfF]) 3228 i - IP address 3229 m - MAC address 3230 3231 The access attributes are: 3232 a - Any (default) 3233 r - Read-only 3234 o - Write-once 3235 c - Change-default 3236 3237 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3238 Define this to a list (string) to define the ".flags" 3239 envirnoment variable in the default or embedded environment. 3240 3241 - CONFIG_ENV_FLAGS_LIST_STATIC 3242 Define this to a list (string) to define validation that 3243 should be done if an entry is not found in the ".flags" 3244 environment variable. To override a setting in the static 3245 list, simply add an entry for the same variable name to the 3246 ".flags" variable. 3247 3248- CONFIG_ENV_ACCESS_IGNORE_FORCE 3249 If defined, don't allow the -f switch to env set override variable 3250 access flags. 3251 3252- CONFIG_SYS_GENERIC_BOARD 3253 This selects the architecture-generic board system instead of the 3254 architecture-specific board files. It is intended to move boards 3255 to this new framework over time. Defining this will disable the 3256 arch/foo/lib/board.c file and use common/board_f.c and 3257 common/board_r.c instead. To use this option your architecture 3258 must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in 3259 its config.mk file). If you find problems enabling this option on 3260 your board please report the problem and send patches! 3261 3262- CONFIG_SYS_SYM_OFFSETS 3263 This is set by architectures that use offsets for link symbols 3264 instead of absolute values. So bss_start is obtained using an 3265 offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than 3266 directly. You should not need to touch this setting. 3267 3268 3269The following definitions that deal with the placement and management 3270of environment data (variable area); in general, we support the 3271following configurations: 3272 3273- CONFIG_BUILD_ENVCRC: 3274 3275 Builds up envcrc with the target environment so that external utils 3276 may easily extract it and embed it in final U-Boot images. 3277 3278- CONFIG_ENV_IS_IN_FLASH: 3279 3280 Define this if the environment is in flash memory. 3281 3282 a) The environment occupies one whole flash sector, which is 3283 "embedded" in the text segment with the U-Boot code. This 3284 happens usually with "bottom boot sector" or "top boot 3285 sector" type flash chips, which have several smaller 3286 sectors at the start or the end. For instance, such a 3287 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3288 such a case you would place the environment in one of the 3289 4 kB sectors - with U-Boot code before and after it. With 3290 "top boot sector" type flash chips, you would put the 3291 environment in one of the last sectors, leaving a gap 3292 between U-Boot and the environment. 3293 3294 - CONFIG_ENV_OFFSET: 3295 3296 Offset of environment data (variable area) to the 3297 beginning of flash memory; for instance, with bottom boot 3298 type flash chips the second sector can be used: the offset 3299 for this sector is given here. 3300 3301 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3302 3303 - CONFIG_ENV_ADDR: 3304 3305 This is just another way to specify the start address of 3306 the flash sector containing the environment (instead of 3307 CONFIG_ENV_OFFSET). 3308 3309 - CONFIG_ENV_SECT_SIZE: 3310 3311 Size of the sector containing the environment. 3312 3313 3314 b) Sometimes flash chips have few, equal sized, BIG sectors. 3315 In such a case you don't want to spend a whole sector for 3316 the environment. 3317 3318 - CONFIG_ENV_SIZE: 3319 3320 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3321 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3322 of this flash sector for the environment. This saves 3323 memory for the RAM copy of the environment. 3324 3325 It may also save flash memory if you decide to use this 3326 when your environment is "embedded" within U-Boot code, 3327 since then the remainder of the flash sector could be used 3328 for U-Boot code. It should be pointed out that this is 3329 STRONGLY DISCOURAGED from a robustness point of view: 3330 updating the environment in flash makes it always 3331 necessary to erase the WHOLE sector. If something goes 3332 wrong before the contents has been restored from a copy in 3333 RAM, your target system will be dead. 3334 3335 - CONFIG_ENV_ADDR_REDUND 3336 CONFIG_ENV_SIZE_REDUND 3337 3338 These settings describe a second storage area used to hold 3339 a redundant copy of the environment data, so that there is 3340 a valid backup copy in case there is a power failure during 3341 a "saveenv" operation. 3342 3343BE CAREFUL! Any changes to the flash layout, and some changes to the 3344source code will make it necessary to adapt <board>/u-boot.lds* 3345accordingly! 3346 3347 3348- CONFIG_ENV_IS_IN_NVRAM: 3349 3350 Define this if you have some non-volatile memory device 3351 (NVRAM, battery buffered SRAM) which you want to use for the 3352 environment. 3353 3354 - CONFIG_ENV_ADDR: 3355 - CONFIG_ENV_SIZE: 3356 3357 These two #defines are used to determine the memory area you 3358 want to use for environment. It is assumed that this memory 3359 can just be read and written to, without any special 3360 provision. 3361 3362BE CAREFUL! The first access to the environment happens quite early 3363in U-Boot initalization (when we try to get the setting of for the 3364console baudrate). You *MUST* have mapped your NVRAM area then, or 3365U-Boot will hang. 3366 3367Please note that even with NVRAM we still use a copy of the 3368environment in RAM: we could work on NVRAM directly, but we want to 3369keep settings there always unmodified except somebody uses "saveenv" 3370to save the current settings. 3371 3372 3373- CONFIG_ENV_IS_IN_EEPROM: 3374 3375 Use this if you have an EEPROM or similar serial access 3376 device and a driver for it. 3377 3378 - CONFIG_ENV_OFFSET: 3379 - CONFIG_ENV_SIZE: 3380 3381 These two #defines specify the offset and size of the 3382 environment area within the total memory of your EEPROM. 3383 3384 - CONFIG_SYS_I2C_EEPROM_ADDR: 3385 If defined, specified the chip address of the EEPROM device. 3386 The default address is zero. 3387 3388 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3389 If defined, the number of bits used to address bytes in a 3390 single page in the EEPROM device. A 64 byte page, for example 3391 would require six bits. 3392 3393 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3394 If defined, the number of milliseconds to delay between 3395 page writes. The default is zero milliseconds. 3396 3397 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3398 The length in bytes of the EEPROM memory array address. Note 3399 that this is NOT the chip address length! 3400 3401 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3402 EEPROM chips that implement "address overflow" are ones 3403 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3404 address and the extra bits end up in the "chip address" bit 3405 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3406 byte chips. 3407 3408 Note that we consider the length of the address field to 3409 still be one byte because the extra address bits are hidden 3410 in the chip address. 3411 3412 - CONFIG_SYS_EEPROM_SIZE: 3413 The size in bytes of the EEPROM device. 3414 3415 - CONFIG_ENV_EEPROM_IS_ON_I2C 3416 define this, if you have I2C and SPI activated, and your 3417 EEPROM, which holds the environment, is on the I2C bus. 3418 3419 - CONFIG_I2C_ENV_EEPROM_BUS 3420 if you have an Environment on an EEPROM reached over 3421 I2C muxes, you can define here, how to reach this 3422 EEPROM. For example: 3423 3424 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0" 3425 3426 EEPROM which holds the environment, is reached over 3427 a pca9547 i2c mux with address 0x70, channel 3. 3428 3429- CONFIG_ENV_IS_IN_DATAFLASH: 3430 3431 Define this if you have a DataFlash memory device which you 3432 want to use for the environment. 3433 3434 - CONFIG_ENV_OFFSET: 3435 - CONFIG_ENV_ADDR: 3436 - CONFIG_ENV_SIZE: 3437 3438 These three #defines specify the offset and size of the 3439 environment area within the total memory of your DataFlash placed 3440 at the specified address. 3441 3442- CONFIG_ENV_IS_IN_REMOTE: 3443 3444 Define this if you have a remote memory space which you 3445 want to use for the local device's environment. 3446 3447 - CONFIG_ENV_ADDR: 3448 - CONFIG_ENV_SIZE: 3449 3450 These two #defines specify the address and size of the 3451 environment area within the remote memory space. The 3452 local device can get the environment from remote memory 3453 space by SRIO or PCIE links. 3454 3455BE CAREFUL! For some special cases, the local device can not use 3456"saveenv" command. For example, the local device will get the 3457environment stored in a remote NOR flash by SRIO or PCIE link, 3458but it can not erase, write this NOR flash by SRIO or PCIE interface. 3459 3460- CONFIG_ENV_IS_IN_NAND: 3461 3462 Define this if you have a NAND device which you want to use 3463 for the environment. 3464 3465 - CONFIG_ENV_OFFSET: 3466 - CONFIG_ENV_SIZE: 3467 3468 These two #defines specify the offset and size of the environment 3469 area within the first NAND device. CONFIG_ENV_OFFSET must be 3470 aligned to an erase block boundary. 3471 3472 - CONFIG_ENV_OFFSET_REDUND (optional): 3473 3474 This setting describes a second storage area of CONFIG_ENV_SIZE 3475 size used to hold a redundant copy of the environment data, so 3476 that there is a valid backup copy in case there is a power failure 3477 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 3478 aligned to an erase block boundary. 3479 3480 - CONFIG_ENV_RANGE (optional): 3481 3482 Specifies the length of the region in which the environment 3483 can be written. This should be a multiple of the NAND device's 3484 block size. Specifying a range with more erase blocks than 3485 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3486 the range to be avoided. 3487 3488 - CONFIG_ENV_OFFSET_OOB (optional): 3489 3490 Enables support for dynamically retrieving the offset of the 3491 environment from block zero's out-of-band data. The 3492 "nand env.oob" command can be used to record this offset. 3493 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 3494 using CONFIG_ENV_OFFSET_OOB. 3495 3496- CONFIG_NAND_ENV_DST 3497 3498 Defines address in RAM to which the nand_spl code should copy the 3499 environment. If redundant environment is used, it will be copied to 3500 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3501 3502- CONFIG_SYS_SPI_INIT_OFFSET 3503 3504 Defines offset to the initial SPI buffer area in DPRAM. The 3505 area is used at an early stage (ROM part) if the environment 3506 is configured to reside in the SPI EEPROM: We need a 520 byte 3507 scratch DPRAM area. It is used between the two initialization 3508 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 3509 to be a good choice since it makes it far enough from the 3510 start of the data area as well as from the stack pointer. 3511 3512Please note that the environment is read-only until the monitor 3513has been relocated to RAM and a RAM copy of the environment has been 3514created; also, when using EEPROM you will have to use getenv_f() 3515until then to read environment variables. 3516 3517The environment is protected by a CRC32 checksum. Before the monitor 3518is relocated into RAM, as a result of a bad CRC you will be working 3519with the compiled-in default environment - *silently*!!! [This is 3520necessary, because the first environment variable we need is the 3521"baudrate" setting for the console - if we have a bad CRC, we don't 3522have any device yet where we could complain.] 3523 3524Note: once the monitor has been relocated, then it will complain if 3525the default environment is used; a new CRC is computed as soon as you 3526use the "saveenv" command to store a valid environment. 3527 3528- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 3529 Echo the inverted Ethernet link state to the fault LED. 3530 3531 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 3532 also needs to be defined. 3533 3534- CONFIG_SYS_FAULT_MII_ADDR: 3535 MII address of the PHY to check for the Ethernet link state. 3536 3537- CONFIG_NS16550_MIN_FUNCTIONS: 3538 Define this if you desire to only have use of the NS16550_init 3539 and NS16550_putc functions for the serial driver located at 3540 drivers/serial/ns16550.c. This option is useful for saving 3541 space for already greatly restricted images, including but not 3542 limited to NAND_SPL configurations. 3543 3544- CONFIG_DISPLAY_BOARDINFO 3545 Display information about the board that U-Boot is running on 3546 when U-Boot starts up. The board function checkboard() is called 3547 to do this. 3548 3549- CONFIG_DISPLAY_BOARDINFO_LATE 3550 Similar to the previous option, but display this information 3551 later, once stdio is running and output goes to the LCD, if 3552 present. 3553 3554Low Level (hardware related) configuration options: 3555--------------------------------------------------- 3556 3557- CONFIG_SYS_CACHELINE_SIZE: 3558 Cache Line Size of the CPU. 3559 3560- CONFIG_SYS_DEFAULT_IMMR: 3561 Default address of the IMMR after system reset. 3562 3563 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 3564 and RPXsuper) to be able to adjust the position of 3565 the IMMR register after a reset. 3566 3567- CONFIG_SYS_CCSRBAR_DEFAULT: 3568 Default (power-on reset) physical address of CCSR on Freescale 3569 PowerPC SOCs. 3570 3571- CONFIG_SYS_CCSRBAR: 3572 Virtual address of CCSR. On a 32-bit build, this is typically 3573 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 3574 3575 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 3576 for cross-platform code that uses that macro instead. 3577 3578- CONFIG_SYS_CCSRBAR_PHYS: 3579 Physical address of CCSR. CCSR can be relocated to a new 3580 physical address, if desired. In this case, this macro should 3581 be set to that address. Otherwise, it should be set to the 3582 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 3583 is typically relocated on 36-bit builds. It is recommended 3584 that this macro be defined via the _HIGH and _LOW macros: 3585 3586 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 3587 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 3588 3589- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 3590 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 3591 either 0 (32-bit build) or 0xF (36-bit build). This macro is 3592 used in assembly code, so it must not contain typecasts or 3593 integer size suffixes (e.g. "ULL"). 3594 3595- CONFIG_SYS_CCSRBAR_PHYS_LOW: 3596 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 3597 used in assembly code, so it must not contain typecasts or 3598 integer size suffixes (e.g. "ULL"). 3599 3600- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 3601 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 3602 forced to a value that ensures that CCSR is not relocated. 3603 3604- Floppy Disk Support: 3605 CONFIG_SYS_FDC_DRIVE_NUMBER 3606 3607 the default drive number (default value 0) 3608 3609 CONFIG_SYS_ISA_IO_STRIDE 3610 3611 defines the spacing between FDC chipset registers 3612 (default value 1) 3613 3614 CONFIG_SYS_ISA_IO_OFFSET 3615 3616 defines the offset of register from address. It 3617 depends on which part of the data bus is connected to 3618 the FDC chipset. (default value 0) 3619 3620 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 3621 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 3622 default value. 3623 3624 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 3625 fdc_hw_init() is called at the beginning of the FDC 3626 setup. fdc_hw_init() must be provided by the board 3627 source code. It is used to make hardware dependant 3628 initializations. 3629 3630- CONFIG_IDE_AHB: 3631 Most IDE controllers were designed to be connected with PCI 3632 interface. Only few of them were designed for AHB interface. 3633 When software is doing ATA command and data transfer to 3634 IDE devices through IDE-AHB controller, some additional 3635 registers accessing to these kind of IDE-AHB controller 3636 is requierd. 3637 3638- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 3639 DO NOT CHANGE unless you know exactly what you're 3640 doing! (11-4) [MPC8xx/82xx systems only] 3641 3642- CONFIG_SYS_INIT_RAM_ADDR: 3643 3644 Start address of memory area that can be used for 3645 initial data and stack; please note that this must be 3646 writable memory that is working WITHOUT special 3647 initialization, i. e. you CANNOT use normal RAM which 3648 will become available only after programming the 3649 memory controller and running certain initialization 3650 sequences. 3651 3652 U-Boot uses the following memory types: 3653 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 3654 - MPC824X: data cache 3655 - PPC4xx: data cache 3656 3657- CONFIG_SYS_GBL_DATA_OFFSET: 3658 3659 Offset of the initial data structure in the memory 3660 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 3661 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 3662 data is located at the end of the available space 3663 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 3664 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 3665 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 3666 CONFIG_SYS_GBL_DATA_OFFSET) downward. 3667 3668 Note: 3669 On the MPC824X (or other systems that use the data 3670 cache for initial memory) the address chosen for 3671 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 3672 point to an otherwise UNUSED address space between 3673 the top of RAM and the start of the PCI space. 3674 3675- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 3676 3677- CONFIG_SYS_SYPCR: System Protection Control (11-9) 3678 3679- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 3680 3681- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 3682 3683- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 3684 3685- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 3686 3687- CONFIG_SYS_OR_TIMING_SDRAM: 3688 SDRAM timing 3689 3690- CONFIG_SYS_MAMR_PTA: 3691 periodic timer for refresh 3692 3693- CONFIG_SYS_DER: Debug Event Register (37-47) 3694 3695- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 3696 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 3697 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 3698 CONFIG_SYS_BR1_PRELIM: 3699 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 3700 3701- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 3702 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 3703 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 3704 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 3705 3706- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 3707 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 3708 Machine Mode Register and Memory Periodic Timer 3709 Prescaler definitions (SDRAM timing) 3710 3711- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 3712 enable I2C microcode relocation patch (MPC8xx); 3713 define relocation offset in DPRAM [DSP2] 3714 3715- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 3716 enable SMC microcode relocation patch (MPC8xx); 3717 define relocation offset in DPRAM [SMC1] 3718 3719- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 3720 enable SPI microcode relocation patch (MPC8xx); 3721 define relocation offset in DPRAM [SCC4] 3722 3723- CONFIG_SYS_USE_OSCCLK: 3724 Use OSCM clock mode on MBX8xx board. Be careful, 3725 wrong setting might damage your board. Read 3726 doc/README.MBX before setting this variable! 3727 3728- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 3729 Offset of the bootmode word in DPRAM used by post 3730 (Power On Self Tests). This definition overrides 3731 #define'd default value in commproc.h resp. 3732 cpm_8260.h. 3733 3734- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 3735 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 3736 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 3737 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 3738 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 3739 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 3740 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 3741 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 3742 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 3743 3744- CONFIG_PCI_DISABLE_PCIE: 3745 Disable PCI-Express on systems where it is supported but not 3746 required. 3747 3748- CONFIG_PCI_ENUM_ONLY 3749 Only scan through and get the devices on the busses. 3750 Don't do any setup work, presumably because someone or 3751 something has already done it, and we don't need to do it 3752 a second time. Useful for platforms that are pre-booted 3753 by coreboot or similar. 3754 3755- CONFIG_SYS_SRIO: 3756 Chip has SRIO or not 3757 3758- CONFIG_SRIO1: 3759 Board has SRIO 1 port available 3760 3761- CONFIG_SRIO2: 3762 Board has SRIO 2 port available 3763 3764- CONFIG_SYS_SRIOn_MEM_VIRT: 3765 Virtual Address of SRIO port 'n' memory region 3766 3767- CONFIG_SYS_SRIOn_MEM_PHYS: 3768 Physical Address of SRIO port 'n' memory region 3769 3770- CONFIG_SYS_SRIOn_MEM_SIZE: 3771 Size of SRIO port 'n' memory region 3772 3773- CONFIG_SYS_NDFC_16 3774 Defined to tell the NDFC that the NAND chip is using a 3775 16 bit bus. 3776 3777- CONFIG_SYS_NDFC_EBC0_CFG 3778 Sets the EBC0_CFG register for the NDFC. If not defined 3779 a default value will be used. 3780 3781- CONFIG_SPD_EEPROM 3782 Get DDR timing information from an I2C EEPROM. Common 3783 with pluggable memory modules such as SODIMMs 3784 3785 SPD_EEPROM_ADDRESS 3786 I2C address of the SPD EEPROM 3787 3788- CONFIG_SYS_SPD_BUS_NUM 3789 If SPD EEPROM is on an I2C bus other than the first 3790 one, specify here. Note that the value must resolve 3791 to something your driver can deal with. 3792 3793- CONFIG_SYS_DDR_RAW_TIMING 3794 Get DDR timing information from other than SPD. Common with 3795 soldered DDR chips onboard without SPD. DDR raw timing 3796 parameters are extracted from datasheet and hard-coded into 3797 header files or board specific files. 3798 3799- CONFIG_FSL_DDR_INTERACTIVE 3800 Enable interactive DDR debugging. See doc/README.fsl-ddr. 3801 3802- CONFIG_SYS_83XX_DDR_USES_CS0 3803 Only for 83xx systems. If specified, then DDR should 3804 be configured using CS0 and CS1 instead of CS2 and CS3. 3805 3806- CONFIG_ETHER_ON_FEC[12] 3807 Define to enable FEC[12] on a 8xx series processor. 3808 3809- CONFIG_FEC[12]_PHY 3810 Define to the hardcoded PHY address which corresponds 3811 to the given FEC; i. e. 3812 #define CONFIG_FEC1_PHY 4 3813 means that the PHY with address 4 is connected to FEC1 3814 3815 When set to -1, means to probe for first available. 3816 3817- CONFIG_FEC[12]_PHY_NORXERR 3818 The PHY does not have a RXERR line (RMII only). 3819 (so program the FEC to ignore it). 3820 3821- CONFIG_RMII 3822 Enable RMII mode for all FECs. 3823 Note that this is a global option, we can't 3824 have one FEC in standard MII mode and another in RMII mode. 3825 3826- CONFIG_CRC32_VERIFY 3827 Add a verify option to the crc32 command. 3828 The syntax is: 3829 3830 => crc32 -v <address> <count> <crc32> 3831 3832 Where address/count indicate a memory area 3833 and crc32 is the correct crc32 which the 3834 area should have. 3835 3836- CONFIG_LOOPW 3837 Add the "loopw" memory command. This only takes effect if 3838 the memory commands are activated globally (CONFIG_CMD_MEM). 3839 3840- CONFIG_MX_CYCLIC 3841 Add the "mdc" and "mwc" memory commands. These are cyclic 3842 "md/mw" commands. 3843 Examples: 3844 3845 => mdc.b 10 4 500 3846 This command will print 4 bytes (10,11,12,13) each 500 ms. 3847 3848 => mwc.l 100 12345678 10 3849 This command will write 12345678 to address 100 all 10 ms. 3850 3851 This only takes effect if the memory commands are activated 3852 globally (CONFIG_CMD_MEM). 3853 3854- CONFIG_SKIP_LOWLEVEL_INIT 3855 [ARM, NDS32, MIPS only] If this variable is defined, then certain 3856 low level initializations (like setting up the memory 3857 controller) are omitted and/or U-Boot does not 3858 relocate itself into RAM. 3859 3860 Normally this variable MUST NOT be defined. The only 3861 exception is when U-Boot is loaded (to RAM) by some 3862 other boot loader or by a debugger which performs 3863 these initializations itself. 3864 3865- CONFIG_SPL_BUILD 3866 Modifies the behaviour of start.S when compiling a loader 3867 that is executed before the actual U-Boot. E.g. when 3868 compiling a NAND SPL. 3869 3870- CONFIG_ARCH_MAP_SYSMEM 3871 Generally U-Boot (and in particular the md command) uses 3872 effective address. It is therefore not necessary to regard 3873 U-Boot address as virtual addresses that need to be translated 3874 to physical addresses. However, sandbox requires this, since 3875 it maintains its own little RAM buffer which contains all 3876 addressable memory. This option causes some memory accesses 3877 to be mapped through map_sysmem() / unmap_sysmem(). 3878 3879- CONFIG_USE_ARCH_MEMCPY 3880 CONFIG_USE_ARCH_MEMSET 3881 If these options are used a optimized version of memcpy/memset will 3882 be used if available. These functions may be faster under some 3883 conditions but may increase the binary size. 3884 3885- CONFIG_X86_RESET_VECTOR 3886 If defined, the x86 reset vector code is included. This is not 3887 needed when U-Boot is running from Coreboot. 3888 3889- CONFIG_SYS_MPUCLK 3890 Defines the MPU clock speed (in MHz). 3891 3892 NOTE : currently only supported on AM335x platforms. 3893 3894Freescale QE/FMAN Firmware Support: 3895----------------------------------- 3896 3897The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 3898loading of "firmware", which is encoded in the QE firmware binary format. 3899This firmware often needs to be loaded during U-Boot booting, so macros 3900are used to identify the storage device (NOR flash, SPI, etc) and the address 3901within that device. 3902 3903- CONFIG_SYS_QE_FMAN_FW_ADDR 3904 The address in the storage device where the firmware is located. The 3905 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 3906 is also specified. 3907 3908- CONFIG_SYS_QE_FMAN_FW_LENGTH 3909 The maximum possible size of the firmware. The firmware binary format 3910 has a field that specifies the actual size of the firmware, but it 3911 might not be possible to read any part of the firmware unless some 3912 local storage is allocated to hold the entire firmware first. 3913 3914- CONFIG_SYS_QE_FMAN_FW_IN_NOR 3915 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 3916 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 3917 virtual address in NOR flash. 3918 3919- CONFIG_SYS_QE_FMAN_FW_IN_NAND 3920 Specifies that QE/FMAN firmware is located in NAND flash. 3921 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 3922 3923- CONFIG_SYS_QE_FMAN_FW_IN_MMC 3924 Specifies that QE/FMAN firmware is located on the primary SD/MMC 3925 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3926 3927- CONFIG_SYS_QE_FMAN_FW_IN_SPIFLASH 3928 Specifies that QE/FMAN firmware is located on the primary SPI 3929 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3930 3931- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 3932 Specifies that QE/FMAN firmware is located in the remote (master) 3933 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 3934 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 3935 window->master inbound window->master LAW->the ucode address in 3936 master's memory space. 3937 3938Building the Software: 3939====================== 3940 3941Building U-Boot has been tested in several native build environments 3942and in many different cross environments. Of course we cannot support 3943all possibly existing versions of cross development tools in all 3944(potentially obsolete) versions. In case of tool chain problems we 3945recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 3946which is extensively used to build and test U-Boot. 3947 3948If you are not using a native environment, it is assumed that you 3949have GNU cross compiling tools available in your path. In this case, 3950you must set the environment variable CROSS_COMPILE in your shell. 3951Note that no changes to the Makefile or any other source files are 3952necessary. For example using the ELDK on a 4xx CPU, please enter: 3953 3954 $ CROSS_COMPILE=ppc_4xx- 3955 $ export CROSS_COMPILE 3956 3957Note: If you wish to generate Windows versions of the utilities in 3958 the tools directory you can use the MinGW toolchain 3959 (http://www.mingw.org). Set your HOST tools to the MinGW 3960 toolchain and execute 'make tools'. For example: 3961 3962 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 3963 3964 Binaries such as tools/mkimage.exe will be created which can 3965 be executed on computers running Windows. 3966 3967U-Boot is intended to be simple to build. After installing the 3968sources you must configure U-Boot for one specific board type. This 3969is done by typing: 3970 3971 make NAME_config 3972 3973where "NAME_config" is the name of one of the existing configu- 3974rations; see boards.cfg for supported names. 3975 3976Note: for some board special configuration names may exist; check if 3977 additional information is available from the board vendor; for 3978 instance, the TQM823L systems are available without (standard) 3979 or with LCD support. You can select such additional "features" 3980 when choosing the configuration, i. e. 3981 3982 make TQM823L_config 3983 - will configure for a plain TQM823L, i. e. no LCD support 3984 3985 make TQM823L_LCD_config 3986 - will configure for a TQM823L with U-Boot console on LCD 3987 3988 etc. 3989 3990 3991Finally, type "make all", and you should get some working U-Boot 3992images ready for download to / installation on your system: 3993 3994- "u-boot.bin" is a raw binary image 3995- "u-boot" is an image in ELF binary format 3996- "u-boot.srec" is in Motorola S-Record format 3997 3998By default the build is performed locally and the objects are saved 3999in the source directory. One of the two methods can be used to change 4000this behavior and build U-Boot to some external directory: 4001 40021. Add O= to the make command line invocations: 4003 4004 make O=/tmp/build distclean 4005 make O=/tmp/build NAME_config 4006 make O=/tmp/build all 4007 40082. Set environment variable BUILD_DIR to point to the desired location: 4009 4010 export BUILD_DIR=/tmp/build 4011 make distclean 4012 make NAME_config 4013 make all 4014 4015Note that the command line "O=" setting overrides the BUILD_DIR environment 4016variable. 4017 4018 4019Please be aware that the Makefiles assume you are using GNU make, so 4020for instance on NetBSD you might need to use "gmake" instead of 4021native "make". 4022 4023 4024If the system board that you have is not listed, then you will need 4025to port U-Boot to your hardware platform. To do this, follow these 4026steps: 4027 40281. Add a new configuration option for your board to the toplevel 4029 "boards.cfg" file, using the existing entries as examples. 4030 Follow the instructions there to keep the boards in order. 40312. Create a new directory to hold your board specific code. Add any 4032 files you need. In your board directory, you will need at least 4033 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 40343. Create a new configuration file "include/configs/<board>.h" for 4035 your board 40363. If you're porting U-Boot to a new CPU, then also create a new 4037 directory to hold your CPU specific code. Add any files you need. 40384. Run "make <board>_config" with your new name. 40395. Type "make", and you should get a working "u-boot.srec" file 4040 to be installed on your target system. 40416. Debug and solve any problems that might arise. 4042 [Of course, this last step is much harder than it sounds.] 4043 4044 4045Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4046============================================================== 4047 4048If you have modified U-Boot sources (for instance added a new board 4049or support for new devices, a new CPU, etc.) you are expected to 4050provide feedback to the other developers. The feedback normally takes 4051the form of a "patch", i. e. a context diff against a certain (latest 4052official or latest in the git repository) version of U-Boot sources. 4053 4054But before you submit such a patch, please verify that your modifi- 4055cation did not break existing code. At least make sure that *ALL* of 4056the supported boards compile WITHOUT ANY compiler warnings. To do so, 4057just run the "MAKEALL" script, which will configure and build U-Boot 4058for ALL supported system. Be warned, this will take a while. You can 4059select which (cross) compiler to use by passing a `CROSS_COMPILE' 4060environment variable to the script, i. e. to use the ELDK cross tools 4061you can type 4062 4063 CROSS_COMPILE=ppc_8xx- MAKEALL 4064 4065or to build on a native PowerPC system you can type 4066 4067 CROSS_COMPILE=' ' MAKEALL 4068 4069When using the MAKEALL script, the default behaviour is to build 4070U-Boot in the source directory. This location can be changed by 4071setting the BUILD_DIR environment variable. Also, for each target 4072built, the MAKEALL script saves two log files (<target>.ERR and 4073<target>.MAKEALL) in the <source dir>/LOG directory. This default 4074location can be changed by setting the MAKEALL_LOGDIR environment 4075variable. For example: 4076 4077 export BUILD_DIR=/tmp/build 4078 export MAKEALL_LOGDIR=/tmp/log 4079 CROSS_COMPILE=ppc_8xx- MAKEALL 4080 4081With the above settings build objects are saved in the /tmp/build, 4082log files are saved in the /tmp/log and the source tree remains clean 4083during the whole build process. 4084 4085 4086See also "U-Boot Porting Guide" below. 4087 4088 4089Monitor Commands - Overview: 4090============================ 4091 4092go - start application at address 'addr' 4093run - run commands in an environment variable 4094bootm - boot application image from memory 4095bootp - boot image via network using BootP/TFTP protocol 4096bootz - boot zImage from memory 4097tftpboot- boot image via network using TFTP protocol 4098 and env variables "ipaddr" and "serverip" 4099 (and eventually "gatewayip") 4100tftpput - upload a file via network using TFTP protocol 4101rarpboot- boot image via network using RARP/TFTP protocol 4102diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4103loads - load S-Record file over serial line 4104loadb - load binary file over serial line (kermit mode) 4105md - memory display 4106mm - memory modify (auto-incrementing) 4107nm - memory modify (constant address) 4108mw - memory write (fill) 4109cp - memory copy 4110cmp - memory compare 4111crc32 - checksum calculation 4112i2c - I2C sub-system 4113sspi - SPI utility commands 4114base - print or set address offset 4115printenv- print environment variables 4116setenv - set environment variables 4117saveenv - save environment variables to persistent storage 4118protect - enable or disable FLASH write protection 4119erase - erase FLASH memory 4120flinfo - print FLASH memory information 4121nand - NAND memory operations (see doc/README.nand) 4122bdinfo - print Board Info structure 4123iminfo - print header information for application image 4124coninfo - print console devices and informations 4125ide - IDE sub-system 4126loop - infinite loop on address range 4127loopw - infinite write loop on address range 4128mtest - simple RAM test 4129icache - enable or disable instruction cache 4130dcache - enable or disable data cache 4131reset - Perform RESET of the CPU 4132echo - echo args to console 4133version - print monitor version 4134help - print online help 4135? - alias for 'help' 4136 4137 4138Monitor Commands - Detailed Description: 4139======================================== 4140 4141TODO. 4142 4143For now: just type "help <command>". 4144 4145 4146Environment Variables: 4147====================== 4148 4149U-Boot supports user configuration using Environment Variables which 4150can be made persistent by saving to Flash memory. 4151 4152Environment Variables are set using "setenv", printed using 4153"printenv", and saved to Flash using "saveenv". Using "setenv" 4154without a value can be used to delete a variable from the 4155environment. As long as you don't save the environment you are 4156working with an in-memory copy. In case the Flash area containing the 4157environment is erased by accident, a default environment is provided. 4158 4159Some configuration options can be set using Environment Variables. 4160 4161List of environment variables (most likely not complete): 4162 4163 baudrate - see CONFIG_BAUDRATE 4164 4165 bootdelay - see CONFIG_BOOTDELAY 4166 4167 bootcmd - see CONFIG_BOOTCOMMAND 4168 4169 bootargs - Boot arguments when booting an RTOS image 4170 4171 bootfile - Name of the image to load with TFTP 4172 4173 bootm_low - Memory range available for image processing in the bootm 4174 command can be restricted. This variable is given as 4175 a hexadecimal number and defines lowest address allowed 4176 for use by the bootm command. See also "bootm_size" 4177 environment variable. Address defined by "bootm_low" is 4178 also the base of the initial memory mapping for the Linux 4179 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4180 bootm_mapsize. 4181 4182 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4183 This variable is given as a hexadecimal number and it 4184 defines the size of the memory region starting at base 4185 address bootm_low that is accessible by the Linux kernel 4186 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4187 as the default value if it is defined, and bootm_size is 4188 used otherwise. 4189 4190 bootm_size - Memory range available for image processing in the bootm 4191 command can be restricted. This variable is given as 4192 a hexadecimal number and defines the size of the region 4193 allowed for use by the bootm command. See also "bootm_low" 4194 environment variable. 4195 4196 updatefile - Location of the software update file on a TFTP server, used 4197 by the automatic software update feature. Please refer to 4198 documentation in doc/README.update for more details. 4199 4200 autoload - if set to "no" (any string beginning with 'n'), 4201 "bootp" will just load perform a lookup of the 4202 configuration from the BOOTP server, but not try to 4203 load any image using TFTP 4204 4205 autostart - if set to "yes", an image loaded using the "bootp", 4206 "rarpboot", "tftpboot" or "diskboot" commands will 4207 be automatically started (by internally calling 4208 "bootm") 4209 4210 If set to "no", a standalone image passed to the 4211 "bootm" command will be copied to the load address 4212 (and eventually uncompressed), but NOT be started. 4213 This can be used to load and uncompress arbitrary 4214 data. 4215 4216 fdt_high - if set this restricts the maximum address that the 4217 flattened device tree will be copied into upon boot. 4218 For example, if you have a system with 1 GB memory 4219 at physical address 0x10000000, while Linux kernel 4220 only recognizes the first 704 MB as low memory, you 4221 may need to set fdt_high as 0x3C000000 to have the 4222 device tree blob be copied to the maximum address 4223 of the 704 MB low memory, so that Linux kernel can 4224 access it during the boot procedure. 4225 4226 If this is set to the special value 0xFFFFFFFF then 4227 the fdt will not be copied at all on boot. For this 4228 to work it must reside in writable memory, have 4229 sufficient padding on the end of it for u-boot to 4230 add the information it needs into it, and the memory 4231 must be accessible by the kernel. 4232 4233 fdtcontroladdr- if set this is the address of the control flattened 4234 device tree used by U-Boot when CONFIG_OF_CONTROL is 4235 defined. 4236 4237 i2cfast - (PPC405GP|PPC405EP only) 4238 if set to 'y' configures Linux I2C driver for fast 4239 mode (400kHZ). This environment variable is used in 4240 initialization code. So, for changes to be effective 4241 it must be saved and board must be reset. 4242 4243 initrd_high - restrict positioning of initrd images: 4244 If this variable is not set, initrd images will be 4245 copied to the highest possible address in RAM; this 4246 is usually what you want since it allows for 4247 maximum initrd size. If for some reason you want to 4248 make sure that the initrd image is loaded below the 4249 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4250 variable to a value of "no" or "off" or "0". 4251 Alternatively, you can set it to a maximum upper 4252 address to use (U-Boot will still check that it 4253 does not overwrite the U-Boot stack and data). 4254 4255 For instance, when you have a system with 16 MB 4256 RAM, and want to reserve 4 MB from use by Linux, 4257 you can do this by adding "mem=12M" to the value of 4258 the "bootargs" variable. However, now you must make 4259 sure that the initrd image is placed in the first 4260 12 MB as well - this can be done with 4261 4262 setenv initrd_high 00c00000 4263 4264 If you set initrd_high to 0xFFFFFFFF, this is an 4265 indication to U-Boot that all addresses are legal 4266 for the Linux kernel, including addresses in flash 4267 memory. In this case U-Boot will NOT COPY the 4268 ramdisk at all. This may be useful to reduce the 4269 boot time on your system, but requires that this 4270 feature is supported by your Linux kernel. 4271 4272 ipaddr - IP address; needed for tftpboot command 4273 4274 loadaddr - Default load address for commands like "bootp", 4275 "rarpboot", "tftpboot", "loadb" or "diskboot" 4276 4277 loads_echo - see CONFIG_LOADS_ECHO 4278 4279 serverip - TFTP server IP address; needed for tftpboot command 4280 4281 bootretry - see CONFIG_BOOT_RETRY_TIME 4282 4283 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4284 4285 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4286 4287 ethprime - controls which interface is used first. 4288 4289 ethact - controls which interface is currently active. 4290 For example you can do the following 4291 4292 => setenv ethact FEC 4293 => ping 192.168.0.1 # traffic sent on FEC 4294 => setenv ethact SCC 4295 => ping 10.0.0.1 # traffic sent on SCC 4296 4297 ethrotate - When set to "no" U-Boot does not go through all 4298 available network interfaces. 4299 It just stays at the currently selected interface. 4300 4301 netretry - When set to "no" each network operation will 4302 either succeed or fail without retrying. 4303 When set to "once" the network operation will 4304 fail when all the available network interfaces 4305 are tried once without success. 4306 Useful on scripts which control the retry operation 4307 themselves. 4308 4309 npe_ucode - set load address for the NPE microcode 4310 4311 tftpsrcport - If this is set, the value is used for TFTP's 4312 UDP source port. 4313 4314 tftpdstport - If this is set, the value is used for TFTP's UDP 4315 destination port instead of the Well Know Port 69. 4316 4317 tftpblocksize - Block size to use for TFTP transfers; if not set, 4318 we use the TFTP server's default block size 4319 4320 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4321 seconds, minimum value is 1000 = 1 second). Defines 4322 when a packet is considered to be lost so it has to 4323 be retransmitted. The default is 5000 = 5 seconds. 4324 Lowering this value may make downloads succeed 4325 faster in networks with high packet loss rates or 4326 with unreliable TFTP servers. 4327 4328 vlan - When set to a value < 4095 the traffic over 4329 Ethernet is encapsulated/received over 802.1q 4330 VLAN tagged frames. 4331 4332The following image location variables contain the location of images 4333used in booting. The "Image" column gives the role of the image and is 4334not an environment variable name. The other columns are environment 4335variable names. "File Name" gives the name of the file on a TFTP 4336server, "RAM Address" gives the location in RAM the image will be 4337loaded to, and "Flash Location" gives the image's address in NOR 4338flash or offset in NAND flash. 4339 4340*Note* - these variables don't have to be defined for all boards, some 4341boards currenlty use other variables for these purposes, and some 4342boards use these variables for other purposes. 4343 4344Image File Name RAM Address Flash Location 4345----- --------- ----------- -------------- 4346u-boot u-boot u-boot_addr_r u-boot_addr 4347Linux kernel bootfile kernel_addr_r kernel_addr 4348device tree blob fdtfile fdt_addr_r fdt_addr 4349ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4350 4351The following environment variables may be used and automatically 4352updated by the network boot commands ("bootp" and "rarpboot"), 4353depending the information provided by your boot server: 4354 4355 bootfile - see above 4356 dnsip - IP address of your Domain Name Server 4357 dnsip2 - IP address of your secondary Domain Name Server 4358 gatewayip - IP address of the Gateway (Router) to use 4359 hostname - Target hostname 4360 ipaddr - see above 4361 netmask - Subnet Mask 4362 rootpath - Pathname of the root filesystem on the NFS server 4363 serverip - see above 4364 4365 4366There are two special Environment Variables: 4367 4368 serial# - contains hardware identification information such 4369 as type string and/or serial number 4370 ethaddr - Ethernet address 4371 4372These variables can be set only once (usually during manufacturing of 4373the board). U-Boot refuses to delete or overwrite these variables 4374once they have been set once. 4375 4376 4377Further special Environment Variables: 4378 4379 ver - Contains the U-Boot version string as printed 4380 with the "version" command. This variable is 4381 readonly (see CONFIG_VERSION_VARIABLE). 4382 4383 4384Please note that changes to some configuration parameters may take 4385only effect after the next boot (yes, that's just like Windoze :-). 4386 4387 4388Callback functions for environment variables: 4389--------------------------------------------- 4390 4391For some environment variables, the behavior of u-boot needs to change 4392when their values are changed. This functionailty allows functions to 4393be associated with arbitrary variables. On creation, overwrite, or 4394deletion, the callback will provide the opportunity for some side 4395effect to happen or for the change to be rejected. 4396 4397The callbacks are named and associated with a function using the 4398U_BOOT_ENV_CALLBACK macro in your board or driver code. 4399 4400These callbacks are associated with variables in one of two ways. The 4401static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 4402in the board configuration to a string that defines a list of 4403associations. The list must be in the following format: 4404 4405 entry = variable_name[:callback_name] 4406 list = entry[,list] 4407 4408If the callback name is not specified, then the callback is deleted. 4409Spaces are also allowed anywhere in the list. 4410 4411Callbacks can also be associated by defining the ".callbacks" variable 4412with the same list format above. Any association in ".callbacks" will 4413override any association in the static list. You can define 4414CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 4415".callbacks" envirnoment variable in the default or embedded environment. 4416 4417 4418Command Line Parsing: 4419===================== 4420 4421There are two different command line parsers available with U-Boot: 4422the old "simple" one, and the much more powerful "hush" shell: 4423 4424Old, simple command line parser: 4425-------------------------------- 4426 4427- supports environment variables (through setenv / saveenv commands) 4428- several commands on one line, separated by ';' 4429- variable substitution using "... ${name} ..." syntax 4430- special characters ('$', ';') can be escaped by prefixing with '\', 4431 for example: 4432 setenv bootcmd bootm \${address} 4433- You can also escape text by enclosing in single apostrophes, for example: 4434 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 4435 4436Hush shell: 4437----------- 4438 4439- similar to Bourne shell, with control structures like 4440 if...then...else...fi, for...do...done; while...do...done, 4441 until...do...done, ... 4442- supports environment ("global") variables (through setenv / saveenv 4443 commands) and local shell variables (through standard shell syntax 4444 "name=value"); only environment variables can be used with "run" 4445 command 4446 4447General rules: 4448-------------- 4449 4450(1) If a command line (or an environment variable executed by a "run" 4451 command) contains several commands separated by semicolon, and 4452 one of these commands fails, then the remaining commands will be 4453 executed anyway. 4454 4455(2) If you execute several variables with one call to run (i. e. 4456 calling run with a list of variables as arguments), any failing 4457 command will cause "run" to terminate, i. e. the remaining 4458 variables are not executed. 4459 4460Note for Redundant Ethernet Interfaces: 4461======================================= 4462 4463Some boards come with redundant Ethernet interfaces; U-Boot supports 4464such configurations and is capable of automatic selection of a 4465"working" interface when needed. MAC assignment works as follows: 4466 4467Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 4468MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 4469"eth1addr" (=>eth1), "eth2addr", ... 4470 4471If the network interface stores some valid MAC address (for instance 4472in SROM), this is used as default address if there is NO correspon- 4473ding setting in the environment; if the corresponding environment 4474variable is set, this overrides the settings in the card; that means: 4475 4476o If the SROM has a valid MAC address, and there is no address in the 4477 environment, the SROM's address is used. 4478 4479o If there is no valid address in the SROM, and a definition in the 4480 environment exists, then the value from the environment variable is 4481 used. 4482 4483o If both the SROM and the environment contain a MAC address, and 4484 both addresses are the same, this MAC address is used. 4485 4486o If both the SROM and the environment contain a MAC address, and the 4487 addresses differ, the value from the environment is used and a 4488 warning is printed. 4489 4490o If neither SROM nor the environment contain a MAC address, an error 4491 is raised. 4492 4493If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 4494will be programmed into hardware as part of the initialization process. This 4495may be skipped by setting the appropriate 'ethmacskip' environment variable. 4496The naming convention is as follows: 4497"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 4498 4499Image Formats: 4500============== 4501 4502U-Boot is capable of booting (and performing other auxiliary operations on) 4503images in two formats: 4504 4505New uImage format (FIT) 4506----------------------- 4507 4508Flexible and powerful format based on Flattened Image Tree -- FIT (similar 4509to Flattened Device Tree). It allows the use of images with multiple 4510components (several kernels, ramdisks, etc.), with contents protected by 4511SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 4512 4513 4514Old uImage format 4515----------------- 4516 4517Old image format is based on binary files which can be basically anything, 4518preceded by a special header; see the definitions in include/image.h for 4519details; basically, the header defines the following image properties: 4520 4521* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 4522 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 4523 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 4524 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 4525 INTEGRITY). 4526* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 4527 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 4528 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 4529* Compression Type (uncompressed, gzip, bzip2) 4530* Load Address 4531* Entry Point 4532* Image Name 4533* Image Timestamp 4534 4535The header is marked by a special Magic Number, and both the header 4536and the data portions of the image are secured against corruption by 4537CRC32 checksums. 4538 4539 4540Linux Support: 4541============== 4542 4543Although U-Boot should support any OS or standalone application 4544easily, the main focus has always been on Linux during the design of 4545U-Boot. 4546 4547U-Boot includes many features that so far have been part of some 4548special "boot loader" code within the Linux kernel. Also, any 4549"initrd" images to be used are no longer part of one big Linux image; 4550instead, kernel and "initrd" are separate images. This implementation 4551serves several purposes: 4552 4553- the same features can be used for other OS or standalone 4554 applications (for instance: using compressed images to reduce the 4555 Flash memory footprint) 4556 4557- it becomes much easier to port new Linux kernel versions because 4558 lots of low-level, hardware dependent stuff are done by U-Boot 4559 4560- the same Linux kernel image can now be used with different "initrd" 4561 images; of course this also means that different kernel images can 4562 be run with the same "initrd". This makes testing easier (you don't 4563 have to build a new "zImage.initrd" Linux image when you just 4564 change a file in your "initrd"). Also, a field-upgrade of the 4565 software is easier now. 4566 4567 4568Linux HOWTO: 4569============ 4570 4571Porting Linux to U-Boot based systems: 4572--------------------------------------- 4573 4574U-Boot cannot save you from doing all the necessary modifications to 4575configure the Linux device drivers for use with your target hardware 4576(no, we don't intend to provide a full virtual machine interface to 4577Linux :-). 4578 4579But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 4580 4581Just make sure your machine specific header file (for instance 4582include/asm-ppc/tqm8xx.h) includes the same definition of the Board 4583Information structure as we define in include/asm-<arch>/u-boot.h, 4584and make sure that your definition of IMAP_ADDR uses the same value 4585as your U-Boot configuration in CONFIG_SYS_IMMR. 4586 4587 4588Configuring the Linux kernel: 4589----------------------------- 4590 4591No specific requirements for U-Boot. Make sure you have some root 4592device (initial ramdisk, NFS) for your target system. 4593 4594 4595Building a Linux Image: 4596----------------------- 4597 4598With U-Boot, "normal" build targets like "zImage" or "bzImage" are 4599not used. If you use recent kernel source, a new build target 4600"uImage" will exist which automatically builds an image usable by 4601U-Boot. Most older kernels also have support for a "pImage" target, 4602which was introduced for our predecessor project PPCBoot and uses a 4603100% compatible format. 4604 4605Example: 4606 4607 make TQM850L_config 4608 make oldconfig 4609 make dep 4610 make uImage 4611 4612The "uImage" build target uses a special tool (in 'tools/mkimage') to 4613encapsulate a compressed Linux kernel image with header information, 4614CRC32 checksum etc. for use with U-Boot. This is what we are doing: 4615 4616* build a standard "vmlinux" kernel image (in ELF binary format): 4617 4618* convert the kernel into a raw binary image: 4619 4620 ${CROSS_COMPILE}-objcopy -O binary \ 4621 -R .note -R .comment \ 4622 -S vmlinux linux.bin 4623 4624* compress the binary image: 4625 4626 gzip -9 linux.bin 4627 4628* package compressed binary image for U-Boot: 4629 4630 mkimage -A ppc -O linux -T kernel -C gzip \ 4631 -a 0 -e 0 -n "Linux Kernel Image" \ 4632 -d linux.bin.gz uImage 4633 4634 4635The "mkimage" tool can also be used to create ramdisk images for use 4636with U-Boot, either separated from the Linux kernel image, or 4637combined into one file. "mkimage" encapsulates the images with a 64 4638byte header containing information about target architecture, 4639operating system, image type, compression method, entry points, time 4640stamp, CRC32 checksums, etc. 4641 4642"mkimage" can be called in two ways: to verify existing images and 4643print the header information, or to build new images. 4644 4645In the first form (with "-l" option) mkimage lists the information 4646contained in the header of an existing U-Boot image; this includes 4647checksum verification: 4648 4649 tools/mkimage -l image 4650 -l ==> list image header information 4651 4652The second form (with "-d" option) is used to build a U-Boot image 4653from a "data file" which is used as image payload: 4654 4655 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 4656 -n name -d data_file image 4657 -A ==> set architecture to 'arch' 4658 -O ==> set operating system to 'os' 4659 -T ==> set image type to 'type' 4660 -C ==> set compression type 'comp' 4661 -a ==> set load address to 'addr' (hex) 4662 -e ==> set entry point to 'ep' (hex) 4663 -n ==> set image name to 'name' 4664 -d ==> use image data from 'datafile' 4665 4666Right now, all Linux kernels for PowerPC systems use the same load 4667address (0x00000000), but the entry point address depends on the 4668kernel version: 4669 4670- 2.2.x kernels have the entry point at 0x0000000C, 4671- 2.3.x and later kernels have the entry point at 0x00000000. 4672 4673So a typical call to build a U-Boot image would read: 4674 4675 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4676 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 4677 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 4678 > examples/uImage.TQM850L 4679 Image Name: 2.4.4 kernel for TQM850L 4680 Created: Wed Jul 19 02:34:59 2000 4681 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4682 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4683 Load Address: 0x00000000 4684 Entry Point: 0x00000000 4685 4686To verify the contents of the image (or check for corruption): 4687 4688 -> tools/mkimage -l examples/uImage.TQM850L 4689 Image Name: 2.4.4 kernel for TQM850L 4690 Created: Wed Jul 19 02:34:59 2000 4691 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4692 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4693 Load Address: 0x00000000 4694 Entry Point: 0x00000000 4695 4696NOTE: for embedded systems where boot time is critical you can trade 4697speed for memory and install an UNCOMPRESSED image instead: this 4698needs more space in Flash, but boots much faster since it does not 4699need to be uncompressed: 4700 4701 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 4702 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4703 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 4704 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 4705 > examples/uImage.TQM850L-uncompressed 4706 Image Name: 2.4.4 kernel for TQM850L 4707 Created: Wed Jul 19 02:34:59 2000 4708 Image Type: PowerPC Linux Kernel Image (uncompressed) 4709 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 4710 Load Address: 0x00000000 4711 Entry Point: 0x00000000 4712 4713 4714Similar you can build U-Boot images from a 'ramdisk.image.gz' file 4715when your kernel is intended to use an initial ramdisk: 4716 4717 -> tools/mkimage -n 'Simple Ramdisk Image' \ 4718 > -A ppc -O linux -T ramdisk -C gzip \ 4719 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 4720 Image Name: Simple Ramdisk Image 4721 Created: Wed Jan 12 14:01:50 2000 4722 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4723 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 4724 Load Address: 0x00000000 4725 Entry Point: 0x00000000 4726 4727 4728Installing a Linux Image: 4729------------------------- 4730 4731To downloading a U-Boot image over the serial (console) interface, 4732you must convert the image to S-Record format: 4733 4734 objcopy -I binary -O srec examples/image examples/image.srec 4735 4736The 'objcopy' does not understand the information in the U-Boot 4737image header, so the resulting S-Record file will be relative to 4738address 0x00000000. To load it to a given address, you need to 4739specify the target address as 'offset' parameter with the 'loads' 4740command. 4741 4742Example: install the image to address 0x40100000 (which on the 4743TQM8xxL is in the first Flash bank): 4744 4745 => erase 40100000 401FFFFF 4746 4747 .......... done 4748 Erased 8 sectors 4749 4750 => loads 40100000 4751 ## Ready for S-Record download ... 4752 ~>examples/image.srec 4753 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 4754 ... 4755 15989 15990 15991 15992 4756 [file transfer complete] 4757 [connected] 4758 ## Start Addr = 0x00000000 4759 4760 4761You can check the success of the download using the 'iminfo' command; 4762this includes a checksum verification so you can be sure no data 4763corruption happened: 4764 4765 => imi 40100000 4766 4767 ## Checking Image at 40100000 ... 4768 Image Name: 2.2.13 for initrd on TQM850L 4769 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4770 Data Size: 335725 Bytes = 327 kB = 0 MB 4771 Load Address: 00000000 4772 Entry Point: 0000000c 4773 Verifying Checksum ... OK 4774 4775 4776Boot Linux: 4777----------- 4778 4779The "bootm" command is used to boot an application that is stored in 4780memory (RAM or Flash). In case of a Linux kernel image, the contents 4781of the "bootargs" environment variable is passed to the kernel as 4782parameters. You can check and modify this variable using the 4783"printenv" and "setenv" commands: 4784 4785 4786 => printenv bootargs 4787 bootargs=root=/dev/ram 4788 4789 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4790 4791 => printenv bootargs 4792 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4793 4794 => bootm 40020000 4795 ## Booting Linux kernel at 40020000 ... 4796 Image Name: 2.2.13 for NFS on TQM850L 4797 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4798 Data Size: 381681 Bytes = 372 kB = 0 MB 4799 Load Address: 00000000 4800 Entry Point: 0000000c 4801 Verifying Checksum ... OK 4802 Uncompressing Kernel Image ... OK 4803 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 4804 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4805 time_init: decrementer frequency = 187500000/60 4806 Calibrating delay loop... 49.77 BogoMIPS 4807 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 4808 ... 4809 4810If you want to boot a Linux kernel with initial RAM disk, you pass 4811the memory addresses of both the kernel and the initrd image (PPBCOOT 4812format!) to the "bootm" command: 4813 4814 => imi 40100000 40200000 4815 4816 ## Checking Image at 40100000 ... 4817 Image Name: 2.2.13 for initrd on TQM850L 4818 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4819 Data Size: 335725 Bytes = 327 kB = 0 MB 4820 Load Address: 00000000 4821 Entry Point: 0000000c 4822 Verifying Checksum ... OK 4823 4824 ## Checking Image at 40200000 ... 4825 Image Name: Simple Ramdisk Image 4826 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4827 Data Size: 566530 Bytes = 553 kB = 0 MB 4828 Load Address: 00000000 4829 Entry Point: 00000000 4830 Verifying Checksum ... OK 4831 4832 => bootm 40100000 40200000 4833 ## Booting Linux kernel at 40100000 ... 4834 Image Name: 2.2.13 for initrd on TQM850L 4835 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4836 Data Size: 335725 Bytes = 327 kB = 0 MB 4837 Load Address: 00000000 4838 Entry Point: 0000000c 4839 Verifying Checksum ... OK 4840 Uncompressing Kernel Image ... OK 4841 ## Loading RAMDisk Image at 40200000 ... 4842 Image Name: Simple Ramdisk Image 4843 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4844 Data Size: 566530 Bytes = 553 kB = 0 MB 4845 Load Address: 00000000 4846 Entry Point: 00000000 4847 Verifying Checksum ... OK 4848 Loading Ramdisk ... OK 4849 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 4850 Boot arguments: root=/dev/ram 4851 time_init: decrementer frequency = 187500000/60 4852 Calibrating delay loop... 49.77 BogoMIPS 4853 ... 4854 RAMDISK: Compressed image found at block 0 4855 VFS: Mounted root (ext2 filesystem). 4856 4857 bash# 4858 4859Boot Linux and pass a flat device tree: 4860----------- 4861 4862First, U-Boot must be compiled with the appropriate defines. See the section 4863titled "Linux Kernel Interface" above for a more in depth explanation. The 4864following is an example of how to start a kernel and pass an updated 4865flat device tree: 4866 4867=> print oftaddr 4868oftaddr=0x300000 4869=> print oft 4870oft=oftrees/mpc8540ads.dtb 4871=> tftp $oftaddr $oft 4872Speed: 1000, full duplex 4873Using TSEC0 device 4874TFTP from server 192.168.1.1; our IP address is 192.168.1.101 4875Filename 'oftrees/mpc8540ads.dtb'. 4876Load address: 0x300000 4877Loading: # 4878done 4879Bytes transferred = 4106 (100a hex) 4880=> tftp $loadaddr $bootfile 4881Speed: 1000, full duplex 4882Using TSEC0 device 4883TFTP from server 192.168.1.1; our IP address is 192.168.1.2 4884Filename 'uImage'. 4885Load address: 0x200000 4886Loading:############ 4887done 4888Bytes transferred = 1029407 (fb51f hex) 4889=> print loadaddr 4890loadaddr=200000 4891=> print oftaddr 4892oftaddr=0x300000 4893=> bootm $loadaddr - $oftaddr 4894## Booting image at 00200000 ... 4895 Image Name: Linux-2.6.17-dirty 4896 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4897 Data Size: 1029343 Bytes = 1005.2 kB 4898 Load Address: 00000000 4899 Entry Point: 00000000 4900 Verifying Checksum ... OK 4901 Uncompressing Kernel Image ... OK 4902Booting using flat device tree at 0x300000 4903Using MPC85xx ADS machine description 4904Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 4905[snip] 4906 4907 4908More About U-Boot Image Types: 4909------------------------------ 4910 4911U-Boot supports the following image types: 4912 4913 "Standalone Programs" are directly runnable in the environment 4914 provided by U-Boot; it is expected that (if they behave 4915 well) you can continue to work in U-Boot after return from 4916 the Standalone Program. 4917 "OS Kernel Images" are usually images of some Embedded OS which 4918 will take over control completely. Usually these programs 4919 will install their own set of exception handlers, device 4920 drivers, set up the MMU, etc. - this means, that you cannot 4921 expect to re-enter U-Boot except by resetting the CPU. 4922 "RAMDisk Images" are more or less just data blocks, and their 4923 parameters (address, size) are passed to an OS kernel that is 4924 being started. 4925 "Multi-File Images" contain several images, typically an OS 4926 (Linux) kernel image and one or more data images like 4927 RAMDisks. This construct is useful for instance when you want 4928 to boot over the network using BOOTP etc., where the boot 4929 server provides just a single image file, but you want to get 4930 for instance an OS kernel and a RAMDisk image. 4931 4932 "Multi-File Images" start with a list of image sizes, each 4933 image size (in bytes) specified by an "uint32_t" in network 4934 byte order. This list is terminated by an "(uint32_t)0". 4935 Immediately after the terminating 0 follow the images, one by 4936 one, all aligned on "uint32_t" boundaries (size rounded up to 4937 a multiple of 4 bytes). 4938 4939 "Firmware Images" are binary images containing firmware (like 4940 U-Boot or FPGA images) which usually will be programmed to 4941 flash memory. 4942 4943 "Script files" are command sequences that will be executed by 4944 U-Boot's command interpreter; this feature is especially 4945 useful when you configure U-Boot to use a real shell (hush) 4946 as command interpreter. 4947 4948Booting the Linux zImage: 4949------------------------- 4950 4951On some platforms, it's possible to boot Linux zImage. This is done 4952using the "bootz" command. The syntax of "bootz" command is the same 4953as the syntax of "bootm" command. 4954 4955Note, defining the CONFIG_SUPPORT_INITRD_RAW allows user to supply 4956kernel with raw initrd images. The syntax is slightly different, the 4957address of the initrd must be augmented by it's size, in the following 4958format: "<initrd addres>:<initrd size>". 4959 4960 4961Standalone HOWTO: 4962================= 4963 4964One of the features of U-Boot is that you can dynamically load and 4965run "standalone" applications, which can use some resources of 4966U-Boot like console I/O functions or interrupt services. 4967 4968Two simple examples are included with the sources: 4969 4970"Hello World" Demo: 4971------------------- 4972 4973'examples/hello_world.c' contains a small "Hello World" Demo 4974application; it is automatically compiled when you build U-Boot. 4975It's configured to run at address 0x00040004, so you can play with it 4976like that: 4977 4978 => loads 4979 ## Ready for S-Record download ... 4980 ~>examples/hello_world.srec 4981 1 2 3 4 5 6 7 8 9 10 11 ... 4982 [file transfer complete] 4983 [connected] 4984 ## Start Addr = 0x00040004 4985 4986 => go 40004 Hello World! This is a test. 4987 ## Starting application at 0x00040004 ... 4988 Hello World 4989 argc = 7 4990 argv[0] = "40004" 4991 argv[1] = "Hello" 4992 argv[2] = "World!" 4993 argv[3] = "This" 4994 argv[4] = "is" 4995 argv[5] = "a" 4996 argv[6] = "test." 4997 argv[7] = "<NULL>" 4998 Hit any key to exit ... 4999 5000 ## Application terminated, rc = 0x0 5001 5002Another example, which demonstrates how to register a CPM interrupt 5003handler with the U-Boot code, can be found in 'examples/timer.c'. 5004Here, a CPM timer is set up to generate an interrupt every second. 5005The interrupt service routine is trivial, just printing a '.' 5006character, but this is just a demo program. The application can be 5007controlled by the following keys: 5008 5009 ? - print current values og the CPM Timer registers 5010 b - enable interrupts and start timer 5011 e - stop timer and disable interrupts 5012 q - quit application 5013 5014 => loads 5015 ## Ready for S-Record download ... 5016 ~>examples/timer.srec 5017 1 2 3 4 5 6 7 8 9 10 11 ... 5018 [file transfer complete] 5019 [connected] 5020 ## Start Addr = 0x00040004 5021 5022 => go 40004 5023 ## Starting application at 0x00040004 ... 5024 TIMERS=0xfff00980 5025 Using timer 1 5026 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5027 5028Hit 'b': 5029 [q, b, e, ?] Set interval 1000000 us 5030 Enabling timer 5031Hit '?': 5032 [q, b, e, ?] ........ 5033 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5034Hit '?': 5035 [q, b, e, ?] . 5036 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5037Hit '?': 5038 [q, b, e, ?] . 5039 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5040Hit '?': 5041 [q, b, e, ?] . 5042 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5043Hit 'e': 5044 [q, b, e, ?] ...Stopping timer 5045Hit 'q': 5046 [q, b, e, ?] ## Application terminated, rc = 0x0 5047 5048 5049Minicom warning: 5050================ 5051 5052Over time, many people have reported problems when trying to use the 5053"minicom" terminal emulation program for serial download. I (wd) 5054consider minicom to be broken, and recommend not to use it. Under 5055Unix, I recommend to use C-Kermit for general purpose use (and 5056especially for kermit binary protocol download ("loadb" command), and 5057use "cu" for S-Record download ("loads" command). See 5058http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5059for help with kermit. 5060 5061 5062Nevertheless, if you absolutely want to use it try adding this 5063configuration to your "File transfer protocols" section: 5064 5065 Name Program Name U/D FullScr IO-Red. Multi 5066 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5067 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5068 5069 5070NetBSD Notes: 5071============= 5072 5073Starting at version 0.9.2, U-Boot supports NetBSD both as host 5074(build U-Boot) and target system (boots NetBSD/mpc8xx). 5075 5076Building requires a cross environment; it is known to work on 5077NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5078need gmake since the Makefiles are not compatible with BSD make). 5079Note that the cross-powerpc package does not install include files; 5080attempting to build U-Boot will fail because <machine/ansi.h> is 5081missing. This file has to be installed and patched manually: 5082 5083 # cd /usr/pkg/cross/powerpc-netbsd/include 5084 # mkdir powerpc 5085 # ln -s powerpc machine 5086 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5087 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5088 5089Native builds *don't* work due to incompatibilities between native 5090and U-Boot include files. 5091 5092Booting assumes that (the first part of) the image booted is a 5093stage-2 loader which in turn loads and then invokes the kernel 5094proper. Loader sources will eventually appear in the NetBSD source 5095tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5096meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5097 5098 5099Implementation Internals: 5100========================= 5101 5102The following is not intended to be a complete description of every 5103implementation detail. However, it should help to understand the 5104inner workings of U-Boot and make it easier to port it to custom 5105hardware. 5106 5107 5108Initial Stack, Global Data: 5109--------------------------- 5110 5111The implementation of U-Boot is complicated by the fact that U-Boot 5112starts running out of ROM (flash memory), usually without access to 5113system RAM (because the memory controller is not initialized yet). 5114This means that we don't have writable Data or BSS segments, and BSS 5115is not initialized as zero. To be able to get a C environment working 5116at all, we have to allocate at least a minimal stack. Implementation 5117options for this are defined and restricted by the CPU used: Some CPU 5118models provide on-chip memory (like the IMMR area on MPC8xx and 5119MPC826x processors), on others (parts of) the data cache can be 5120locked as (mis-) used as memory, etc. 5121 5122 Chris Hallinan posted a good summary of these issues to the 5123 U-Boot mailing list: 5124 5125 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5126 From: "Chris Hallinan" <clh@net1plus.com> 5127 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5128 ... 5129 5130 Correct me if I'm wrong, folks, but the way I understand it 5131 is this: Using DCACHE as initial RAM for Stack, etc, does not 5132 require any physical RAM backing up the cache. The cleverness 5133 is that the cache is being used as a temporary supply of 5134 necessary storage before the SDRAM controller is setup. It's 5135 beyond the scope of this list to explain the details, but you 5136 can see how this works by studying the cache architecture and 5137 operation in the architecture and processor-specific manuals. 5138 5139 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5140 is another option for the system designer to use as an 5141 initial stack/RAM area prior to SDRAM being available. Either 5142 option should work for you. Using CS 4 should be fine if your 5143 board designers haven't used it for something that would 5144 cause you grief during the initial boot! It is frequently not 5145 used. 5146 5147 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5148 with your processor/board/system design. The default value 5149 you will find in any recent u-boot distribution in 5150 walnut.h should work for you. I'd set it to a value larger 5151 than your SDRAM module. If you have a 64MB SDRAM module, set 5152 it above 400_0000. Just make sure your board has no resources 5153 that are supposed to respond to that address! That code in 5154 start.S has been around a while and should work as is when 5155 you get the config right. 5156 5157 -Chris Hallinan 5158 DS4.COM, Inc. 5159 5160It is essential to remember this, since it has some impact on the C 5161code for the initialization procedures: 5162 5163* Initialized global data (data segment) is read-only. Do not attempt 5164 to write it. 5165 5166* Do not use any uninitialized global data (or implicitely initialized 5167 as zero data - BSS segment) at all - this is undefined, initiali- 5168 zation is performed later (when relocating to RAM). 5169 5170* Stack space is very limited. Avoid big data buffers or things like 5171 that. 5172 5173Having only the stack as writable memory limits means we cannot use 5174normal global data to share information beween the code. But it 5175turned out that the implementation of U-Boot can be greatly 5176simplified by making a global data structure (gd_t) available to all 5177functions. We could pass a pointer to this data as argument to _all_ 5178functions, but this would bloat the code. Instead we use a feature of 5179the GCC compiler (Global Register Variables) to share the data: we 5180place a pointer (gd) to the global data into a register which we 5181reserve for this purpose. 5182 5183When choosing a register for such a purpose we are restricted by the 5184relevant (E)ABI specifications for the current architecture, and by 5185GCC's implementation. 5186 5187For PowerPC, the following registers have specific use: 5188 R1: stack pointer 5189 R2: reserved for system use 5190 R3-R4: parameter passing and return values 5191 R5-R10: parameter passing 5192 R13: small data area pointer 5193 R30: GOT pointer 5194 R31: frame pointer 5195 5196 (U-Boot also uses R12 as internal GOT pointer. r12 5197 is a volatile register so r12 needs to be reset when 5198 going back and forth between asm and C) 5199 5200 ==> U-Boot will use R2 to hold a pointer to the global data 5201 5202 Note: on PPC, we could use a static initializer (since the 5203 address of the global data structure is known at compile time), 5204 but it turned out that reserving a register results in somewhat 5205 smaller code - although the code savings are not that big (on 5206 average for all boards 752 bytes for the whole U-Boot image, 5207 624 text + 127 data). 5208 5209On Blackfin, the normal C ABI (except for P3) is followed as documented here: 5210 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 5211 5212 ==> U-Boot will use P3 to hold a pointer to the global data 5213 5214On ARM, the following registers are used: 5215 5216 R0: function argument word/integer result 5217 R1-R3: function argument word 5218 R9: GOT pointer 5219 R10: stack limit (used only if stack checking if enabled) 5220 R11: argument (frame) pointer 5221 R12: temporary workspace 5222 R13: stack pointer 5223 R14: link register 5224 R15: program counter 5225 5226 ==> U-Boot will use R8 to hold a pointer to the global data 5227 5228On Nios II, the ABI is documented here: 5229 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5230 5231 ==> U-Boot will use gp to hold a pointer to the global data 5232 5233 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5234 to access small data sections, so gp is free. 5235 5236On NDS32, the following registers are used: 5237 5238 R0-R1: argument/return 5239 R2-R5: argument 5240 R15: temporary register for assembler 5241 R16: trampoline register 5242 R28: frame pointer (FP) 5243 R29: global pointer (GP) 5244 R30: link register (LP) 5245 R31: stack pointer (SP) 5246 PC: program counter (PC) 5247 5248 ==> U-Boot will use R10 to hold a pointer to the global data 5249 5250NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5251or current versions of GCC may "optimize" the code too much. 5252 5253Memory Management: 5254------------------ 5255 5256U-Boot runs in system state and uses physical addresses, i.e. the 5257MMU is not used either for address mapping nor for memory protection. 5258 5259The available memory is mapped to fixed addresses using the memory 5260controller. In this process, a contiguous block is formed for each 5261memory type (Flash, SDRAM, SRAM), even when it consists of several 5262physical memory banks. 5263 5264U-Boot is installed in the first 128 kB of the first Flash bank (on 5265TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5266booting and sizing and initializing DRAM, the code relocates itself 5267to the upper end of DRAM. Immediately below the U-Boot code some 5268memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5269configuration setting]. Below that, a structure with global Board 5270Info data is placed, followed by the stack (growing downward). 5271 5272Additionally, some exception handler code is copied to the low 8 kB 5273of DRAM (0x00000000 ... 0x00001FFF). 5274 5275So a typical memory configuration with 16 MB of DRAM could look like 5276this: 5277 5278 0x0000 0000 Exception Vector code 5279 : 5280 0x0000 1FFF 5281 0x0000 2000 Free for Application Use 5282 : 5283 : 5284 5285 : 5286 : 5287 0x00FB FF20 Monitor Stack (Growing downward) 5288 0x00FB FFAC Board Info Data and permanent copy of global data 5289 0x00FC 0000 Malloc Arena 5290 : 5291 0x00FD FFFF 5292 0x00FE 0000 RAM Copy of Monitor Code 5293 ... eventually: LCD or video framebuffer 5294 ... eventually: pRAM (Protected RAM - unchanged by reset) 5295 0x00FF FFFF [End of RAM] 5296 5297 5298System Initialization: 5299---------------------- 5300 5301In the reset configuration, U-Boot starts at the reset entry point 5302(on most PowerPC systems at address 0x00000100). Because of the reset 5303configuration for CS0# this is a mirror of the onboard Flash memory. 5304To be able to re-map memory U-Boot then jumps to its link address. 5305To be able to implement the initialization code in C, a (small!) 5306initial stack is set up in the internal Dual Ported RAM (in case CPUs 5307which provide such a feature like MPC8xx or MPC8260), or in a locked 5308part of the data cache. After that, U-Boot initializes the CPU core, 5309the caches and the SIU. 5310 5311Next, all (potentially) available memory banks are mapped using a 5312preliminary mapping. For example, we put them on 512 MB boundaries 5313(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5314on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5315programmed for SDRAM access. Using the temporary configuration, a 5316simple memory test is run that determines the size of the SDRAM 5317banks. 5318 5319When there is more than one SDRAM bank, and the banks are of 5320different size, the largest is mapped first. For equal size, the first 5321bank (CS2#) is mapped first. The first mapping is always for address 53220x00000000, with any additional banks following immediately to create 5323contiguous memory starting from 0. 5324 5325Then, the monitor installs itself at the upper end of the SDRAM area 5326and allocates memory for use by malloc() and for the global Board 5327Info data; also, the exception vector code is copied to the low RAM 5328pages, and the final stack is set up. 5329 5330Only after this relocation will you have a "normal" C environment; 5331until that you are restricted in several ways, mostly because you are 5332running from ROM, and because the code will have to be relocated to a 5333new address in RAM. 5334 5335 5336U-Boot Porting Guide: 5337---------------------- 5338 5339[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 5340list, October 2002] 5341 5342 5343int main(int argc, char *argv[]) 5344{ 5345 sighandler_t no_more_time; 5346 5347 signal(SIGALRM, no_more_time); 5348 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 5349 5350 if (available_money > available_manpower) { 5351 Pay consultant to port U-Boot; 5352 return 0; 5353 } 5354 5355 Download latest U-Boot source; 5356 5357 Subscribe to u-boot mailing list; 5358 5359 if (clueless) 5360 email("Hi, I am new to U-Boot, how do I get started?"); 5361 5362 while (learning) { 5363 Read the README file in the top level directory; 5364 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5365 Read applicable doc/*.README; 5366 Read the source, Luke; 5367 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5368 } 5369 5370 if (available_money > toLocalCurrency ($2500)) 5371 Buy a BDI3000; 5372 else 5373 Add a lot of aggravation and time; 5374 5375 if (a similar board exists) { /* hopefully... */ 5376 cp -a board/<similar> board/<myboard> 5377 cp include/configs/<similar>.h include/configs/<myboard>.h 5378 } else { 5379 Create your own board support subdirectory; 5380 Create your own board include/configs/<myboard>.h file; 5381 } 5382 Edit new board/<myboard> files 5383 Edit new include/configs/<myboard>.h 5384 5385 while (!accepted) { 5386 while (!running) { 5387 do { 5388 Add / modify source code; 5389 } until (compiles); 5390 Debug; 5391 if (clueless) 5392 email("Hi, I am having problems..."); 5393 } 5394 Send patch file to the U-Boot email list; 5395 if (reasonable critiques) 5396 Incorporate improvements from email list code review; 5397 else 5398 Defend code as written; 5399 } 5400 5401 return 0; 5402} 5403 5404void no_more_time (int sig) 5405{ 5406 hire_a_guru(); 5407} 5408 5409 5410Coding Standards: 5411----------------- 5412 5413All contributions to U-Boot should conform to the Linux kernel 5414coding style; see the file "Documentation/CodingStyle" and the script 5415"scripts/Lindent" in your Linux kernel source directory. 5416 5417Source files originating from a different project (for example the 5418MTD subsystem) are generally exempt from these guidelines and are not 5419reformated to ease subsequent migration to newer versions of those 5420sources. 5421 5422Please note that U-Boot is implemented in C (and to some small parts in 5423Assembler); no C++ is used, so please do not use C++ style comments (//) 5424in your code. 5425 5426Please also stick to the following formatting rules: 5427- remove any trailing white space 5428- use TAB characters for indentation and vertical alignment, not spaces 5429- make sure NOT to use DOS '\r\n' line feeds 5430- do not add more than 2 consecutive empty lines to source files 5431- do not add trailing empty lines to source files 5432 5433Submissions which do not conform to the standards may be returned 5434with a request to reformat the changes. 5435 5436 5437Submitting Patches: 5438------------------- 5439 5440Since the number of patches for U-Boot is growing, we need to 5441establish some rules. Submissions which do not conform to these rules 5442may be rejected, even when they contain important and valuable stuff. 5443 5444Please see http://www.denx.de/wiki/U-Boot/Patches for details. 5445 5446Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 5447see http://lists.denx.de/mailman/listinfo/u-boot 5448 5449When you send a patch, please include the following information with 5450it: 5451 5452* For bug fixes: a description of the bug and how your patch fixes 5453 this bug. Please try to include a way of demonstrating that the 5454 patch actually fixes something. 5455 5456* For new features: a description of the feature and your 5457 implementation. 5458 5459* A CHANGELOG entry as plaintext (separate from the patch) 5460 5461* For major contributions, your entry to the CREDITS file 5462 5463* When you add support for a new board, don't forget to add this 5464 board to the MAINTAINERS file, too. 5465 5466* If your patch adds new configuration options, don't forget to 5467 document these in the README file. 5468 5469* The patch itself. If you are using git (which is *strongly* 5470 recommended) you can easily generate the patch using the 5471 "git format-patch". If you then use "git send-email" to send it to 5472 the U-Boot mailing list, you will avoid most of the common problems 5473 with some other mail clients. 5474 5475 If you cannot use git, use "diff -purN OLD NEW". If your version of 5476 diff does not support these options, then get the latest version of 5477 GNU diff. 5478 5479 The current directory when running this command shall be the parent 5480 directory of the U-Boot source tree (i. e. please make sure that 5481 your patch includes sufficient directory information for the 5482 affected files). 5483 5484 We prefer patches as plain text. MIME attachments are discouraged, 5485 and compressed attachments must not be used. 5486 5487* If one logical set of modifications affects or creates several 5488 files, all these changes shall be submitted in a SINGLE patch file. 5489 5490* Changesets that contain different, unrelated modifications shall be 5491 submitted as SEPARATE patches, one patch per changeset. 5492 5493 5494Notes: 5495 5496* Before sending the patch, run the MAKEALL script on your patched 5497 source tree and make sure that no errors or warnings are reported 5498 for any of the boards. 5499 5500* Keep your modifications to the necessary minimum: A patch 5501 containing several unrelated changes or arbitrary reformats will be 5502 returned with a request to re-formatting / split it. 5503 5504* If you modify existing code, make sure that your new code does not 5505 add to the memory footprint of the code ;-) Small is beautiful! 5506 When adding new features, these should compile conditionally only 5507 (using #ifdef), and the resulting code with the new feature 5508 disabled must not need more memory than the old code without your 5509 modification. 5510 5511* Remember that there is a size limit of 100 kB per message on the 5512 u-boot mailing list. Bigger patches will be moderated. If they are 5513 reasonable and not too big, they will be acknowledged. But patches 5514 bigger than the size limit should be avoided. 5515