1# 2# (C) Copyright 2000 - 2011 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 57 58Where to get help: 59================== 60 61In case you have questions about, problems with or contributions for 62U-Boot you should send a message to the U-Boot mailing list at 63<u-boot@lists.denx.de>. There is also an archive of previous traffic 64on the mailing list - please search the archive before asking FAQ's. 65Please see http://lists.denx.de/pipermail/u-boot and 66http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 67 68 69Where to get source code: 70========================= 71 72The U-Boot source code is maintained in the git repository at 73git://www.denx.de/git/u-boot.git ; you can browse it online at 74http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 75 76The "snapshot" links on this page allow you to download tarballs of 77any version you might be interested in. Official releases are also 78available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 79directory. 80 81Pre-built (and tested) images are available from 82ftp://ftp.denx.de/pub/u-boot/images/ 83 84 85Where we come from: 86=================== 87 88- start from 8xxrom sources 89- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 90- clean up code 91- make it easier to add custom boards 92- make it possible to add other [PowerPC] CPUs 93- extend functions, especially: 94 * Provide extended interface to Linux boot loader 95 * S-Record download 96 * network boot 97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 98- create ARMBoot project (http://sourceforge.net/projects/armboot) 99- add other CPU families (starting with ARM) 100- create U-Boot project (http://sourceforge.net/projects/u-boot) 101- current project page: see http://www.denx.de/wiki/U-Boot 102 103 104Names and Spelling: 105=================== 106 107The "official" name of this project is "Das U-Boot". The spelling 108"U-Boot" shall be used in all written text (documentation, comments 109in source files etc.). Example: 110 111 This is the README file for the U-Boot project. 112 113File names etc. shall be based on the string "u-boot". Examples: 114 115 include/asm-ppc/u-boot.h 116 117 #include <asm/u-boot.h> 118 119Variable names, preprocessor constants etc. shall be either based on 120the string "u_boot" or on "U_BOOT". Example: 121 122 U_BOOT_VERSION u_boot_logo 123 IH_OS_U_BOOT u_boot_hush_start 124 125 126Versioning: 127=========== 128 129Starting with the release in October 2008, the names of the releases 130were changed from numerical release numbers without deeper meaning 131into a time stamp based numbering. Regular releases are identified by 132names consisting of the calendar year and month of the release date. 133Additional fields (if present) indicate release candidates or bug fix 134releases in "stable" maintenance trees. 135 136Examples: 137 U-Boot v2009.11 - Release November 2009 138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 140 141 142Directory Hierarchy: 143==================== 144 145/arch Architecture specific files 146 /arm Files generic to ARM architecture 147 /cpu CPU specific files 148 /arm720t Files specific to ARM 720 CPUs 149 /arm920t Files specific to ARM 920 CPUs 150 /at91rm9200 Files specific to Atmel AT91RM9200 CPU 151 /imx Files specific to Freescale MC9328 i.MX CPUs 152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 153 /arm925t Files specific to ARM 925 CPUs 154 /arm926ejs Files specific to ARM 926 CPUs 155 /arm1136 Files specific to ARM 1136 CPUs 156 /ixp Files specific to Intel XScale IXP CPUs 157 /pxa Files specific to Intel XScale PXA CPUs 158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs 159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 160 /lib Architecture specific library files 161 /avr32 Files generic to AVR32 architecture 162 /cpu CPU specific files 163 /lib Architecture specific library files 164 /blackfin Files generic to Analog Devices Blackfin architecture 165 /cpu CPU specific files 166 /lib Architecture specific library files 167 /x86 Files generic to x86 architecture 168 /cpu CPU specific files 169 /lib Architecture specific library files 170 /m68k Files generic to m68k architecture 171 /cpu CPU specific files 172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 177 /lib Architecture specific library files 178 /microblaze Files generic to microblaze architecture 179 /cpu CPU specific files 180 /lib Architecture specific library files 181 /mips Files generic to MIPS architecture 182 /cpu CPU specific files 183 /lib Architecture specific library files 184 /nios2 Files generic to Altera NIOS2 architecture 185 /cpu CPU specific files 186 /lib Architecture specific library files 187 /powerpc Files generic to PowerPC architecture 188 /cpu CPU specific files 189 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 190 /mpc5xx Files specific to Freescale MPC5xx CPUs 191 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 192 /mpc8xx Files specific to Freescale MPC8xx CPUs 193 /mpc8220 Files specific to Freescale MPC8220 CPUs 194 /mpc824x Files specific to Freescale MPC824x CPUs 195 /mpc8260 Files specific to Freescale MPC8260 CPUs 196 /mpc85xx Files specific to Freescale MPC85xx CPUs 197 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 198 /lib Architecture specific library files 199 /sh Files generic to SH architecture 200 /cpu CPU specific files 201 /sh2 Files specific to sh2 CPUs 202 /sh3 Files specific to sh3 CPUs 203 /sh4 Files specific to sh4 CPUs 204 /lib Architecture specific library files 205 /sparc Files generic to SPARC architecture 206 /cpu CPU specific files 207 /leon2 Files specific to Gaisler LEON2 SPARC CPU 208 /leon3 Files specific to Gaisler LEON3 SPARC CPU 209 /lib Architecture specific library files 210/api Machine/arch independent API for external apps 211/board Board dependent files 212/common Misc architecture independent functions 213/disk Code for disk drive partition handling 214/doc Documentation (don't expect too much) 215/drivers Commonly used device drivers 216/examples Example code for standalone applications, etc. 217/fs Filesystem code (cramfs, ext2, jffs2, etc.) 218/include Header Files 219/lib Files generic to all architectures 220 /libfdt Library files to support flattened device trees 221 /lzma Library files to support LZMA decompression 222 /lzo Library files to support LZO decompression 223/net Networking code 224/post Power On Self Test 225/rtc Real Time Clock drivers 226/tools Tools to build S-Record or U-Boot images, etc. 227 228Software Configuration: 229======================= 230 231Configuration is usually done using C preprocessor defines; the 232rationale behind that is to avoid dead code whenever possible. 233 234There are two classes of configuration variables: 235 236* Configuration _OPTIONS_: 237 These are selectable by the user and have names beginning with 238 "CONFIG_". 239 240* Configuration _SETTINGS_: 241 These depend on the hardware etc. and should not be meddled with if 242 you don't know what you're doing; they have names beginning with 243 "CONFIG_SYS_". 244 245Later we will add a configuration tool - probably similar to or even 246identical to what's used for the Linux kernel. Right now, we have to 247do the configuration by hand, which means creating some symbolic 248links and editing some configuration files. We use the TQM8xxL boards 249as an example here. 250 251 252Selection of Processor Architecture and Board Type: 253--------------------------------------------------- 254 255For all supported boards there are ready-to-use default 256configurations available; just type "make <board_name>_config". 257 258Example: For a TQM823L module type: 259 260 cd u-boot 261 make TQM823L_config 262 263For the Cogent platform, you need to specify the CPU type as well; 264e.g. "make cogent_mpc8xx_config". And also configure the cogent 265directory according to the instructions in cogent/README. 266 267 268Configuration Options: 269---------------------- 270 271Configuration depends on the combination of board and CPU type; all 272such information is kept in a configuration file 273"include/configs/<board_name>.h". 274 275Example: For a TQM823L module, all configuration settings are in 276"include/configs/TQM823L.h". 277 278 279Many of the options are named exactly as the corresponding Linux 280kernel configuration options. The intention is to make it easier to 281build a config tool - later. 282 283 284The following options need to be configured: 285 286- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 287 288- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 289 290- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 291 Define exactly one, e.g. CONFIG_ATSTK1002 292 293- CPU Module Type: (if CONFIG_COGENT is defined) 294 Define exactly one of 295 CONFIG_CMA286_60_OLD 296--- FIXME --- not tested yet: 297 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 298 CONFIG_CMA287_23, CONFIG_CMA287_50 299 300- Motherboard Type: (if CONFIG_COGENT is defined) 301 Define exactly one of 302 CONFIG_CMA101, CONFIG_CMA102 303 304- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 305 Define one or more of 306 CONFIG_CMA302 307 308- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 309 Define one or more of 310 CONFIG_LCD_HEARTBEAT - update a character position on 311 the LCD display every second with 312 a "rotator" |\-/|\-/ 313 314- Board flavour: (if CONFIG_MPC8260ADS is defined) 315 CONFIG_ADSTYPE 316 Possible values are: 317 CONFIG_SYS_8260ADS - original MPC8260ADS 318 CONFIG_SYS_8266ADS - MPC8266ADS 319 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 320 CONFIG_SYS_8272ADS - MPC8272ADS 321 322- Marvell Family Member 323 CONFIG_SYS_MVFS - define it if you want to enable 324 multiple fs option at one time 325 for marvell soc family 326 327- MPC824X Family Member (if CONFIG_MPC824X is defined) 328 Define exactly one of 329 CONFIG_MPC8240, CONFIG_MPC8245 330 331- 8xx CPU Options: (if using an MPC8xx CPU) 332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 333 get_gclk_freq() cannot work 334 e.g. if there is no 32KHz 335 reference PIT/RTC clock 336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 337 or XTAL/EXTAL) 338 339- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 340 CONFIG_SYS_8xx_CPUCLK_MIN 341 CONFIG_SYS_8xx_CPUCLK_MAX 342 CONFIG_8xx_CPUCLK_DEFAULT 343 See doc/README.MPC866 344 345 CONFIG_SYS_MEASURE_CPUCLK 346 347 Define this to measure the actual CPU clock instead 348 of relying on the correctness of the configured 349 values. Mostly useful for board bringup to make sure 350 the PLL is locked at the intended frequency. Note 351 that this requires a (stable) reference clock (32 kHz 352 RTC clock or CONFIG_SYS_8XX_XIN) 353 354 CONFIG_SYS_DELAYED_ICACHE 355 356 Define this option if you want to enable the 357 ICache only when Code runs from RAM. 358 359- 85xx CPU Options: 360 CONFIG_SYS_FSL_TBCLK_DIV 361 362 Defines the core time base clock divider ratio compared to the 363 system clock. On most PQ3 devices this is 8, on newer QorIQ 364 devices it can be 16 or 32. The ratio varies from SoC to Soc. 365 366 CONFIG_SYS_FSL_PCIE_COMPAT 367 368 Defines the string to utilize when trying to match PCIe device 369 tree nodes for the given platform. 370 371- Intel Monahans options: 372 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 373 374 Defines the Monahans run mode to oscillator 375 ratio. Valid values are 8, 16, 24, 31. The core 376 frequency is this value multiplied by 13 MHz. 377 378 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 379 380 Defines the Monahans turbo mode to oscillator 381 ratio. Valid values are 1 (default if undefined) and 382 2. The core frequency as calculated above is multiplied 383 by this value. 384 385- Linux Kernel Interface: 386 CONFIG_CLOCKS_IN_MHZ 387 388 U-Boot stores all clock information in Hz 389 internally. For binary compatibility with older Linux 390 kernels (which expect the clocks passed in the 391 bd_info data to be in MHz) the environment variable 392 "clocks_in_mhz" can be defined so that U-Boot 393 converts clock data to MHZ before passing it to the 394 Linux kernel. 395 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 396 "clocks_in_mhz=1" is automatically included in the 397 default environment. 398 399 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 400 401 When transferring memsize parameter to linux, some versions 402 expect it to be in bytes, others in MB. 403 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 404 405 CONFIG_OF_LIBFDT 406 407 New kernel versions are expecting firmware settings to be 408 passed using flattened device trees (based on open firmware 409 concepts). 410 411 CONFIG_OF_LIBFDT 412 * New libfdt-based support 413 * Adds the "fdt" command 414 * The bootm command automatically updates the fdt 415 416 OF_CPU - The proper name of the cpus node (only required for 417 MPC512X and MPC5xxx based boards). 418 OF_SOC - The proper name of the soc node (only required for 419 MPC512X and MPC5xxx based boards). 420 OF_TBCLK - The timebase frequency. 421 OF_STDOUT_PATH - The path to the console device 422 423 boards with QUICC Engines require OF_QE to set UCC MAC 424 addresses 425 426 CONFIG_OF_BOARD_SETUP 427 428 Board code has addition modification that it wants to make 429 to the flat device tree before handing it off to the kernel 430 431 CONFIG_OF_BOOT_CPU 432 433 This define fills in the correct boot CPU in the boot 434 param header, the default value is zero if undefined. 435 436 CONFIG_OF_IDE_FIXUP 437 438 U-Boot can detect if an IDE device is present or not. 439 If not, and this new config option is activated, U-Boot 440 removes the ATA node from the DTS before booting Linux, 441 so the Linux IDE driver does not probe the device and 442 crash. This is needed for buggy hardware (uc101) where 443 no pull down resistor is connected to the signal IDE5V_DD7. 444 445 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 446 447 This setting is mandatory for all boards that have only one 448 machine type and must be used to specify the machine type 449 number as it appears in the ARM machine registry 450 (see http://www.arm.linux.org.uk/developer/machines/). 451 Only boards that have multiple machine types supported 452 in a single configuration file and the machine type is 453 runtime discoverable, do not have to use this setting. 454 455- vxWorks boot parameters: 456 457 bootvx constructs a valid bootline using the following 458 environments variables: bootfile, ipaddr, serverip, hostname. 459 It loads the vxWorks image pointed bootfile. 460 461 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 462 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 463 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 464 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 465 466 CONFIG_SYS_VXWORKS_ADD_PARAMS 467 468 Add it at the end of the bootline. E.g "u=username pw=secret" 469 470 Note: If a "bootargs" environment is defined, it will overwride 471 the defaults discussed just above. 472 473- Cache Configuration: 474 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 475 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 476 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 477 478- Cache Configuration for ARM: 479 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 480 controller 481 CONFIG_SYS_PL310_BASE - Physical base address of PL310 482 controller register space 483 484- Serial Ports: 485 CONFIG_PL010_SERIAL 486 487 Define this if you want support for Amba PrimeCell PL010 UARTs. 488 489 CONFIG_PL011_SERIAL 490 491 Define this if you want support for Amba PrimeCell PL011 UARTs. 492 493 CONFIG_PL011_CLOCK 494 495 If you have Amba PrimeCell PL011 UARTs, set this variable to 496 the clock speed of the UARTs. 497 498 CONFIG_PL01x_PORTS 499 500 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 501 define this to a list of base addresses for each (supported) 502 port. See e.g. include/configs/versatile.h 503 504 CONFIG_PL011_SERIAL_RLCR 505 506 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 507 have separate receive and transmit line control registers. Set 508 this variable to initialize the extra register. 509 510 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 511 512 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 513 boot loader that has already initialized the UART. Define this 514 variable to flush the UART at init time. 515 516 517- Console Interface: 518 Depending on board, define exactly one serial port 519 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 520 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 521 console by defining CONFIG_8xx_CONS_NONE 522 523 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 524 port routines must be defined elsewhere 525 (i.e. serial_init(), serial_getc(), ...) 526 527 CONFIG_CFB_CONSOLE 528 Enables console device for a color framebuffer. Needs following 529 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 530 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 531 (default big endian) 532 VIDEO_HW_RECTFILL graphic chip supports 533 rectangle fill 534 (cf. smiLynxEM) 535 VIDEO_HW_BITBLT graphic chip supports 536 bit-blit (cf. smiLynxEM) 537 VIDEO_VISIBLE_COLS visible pixel columns 538 (cols=pitch) 539 VIDEO_VISIBLE_ROWS visible pixel rows 540 VIDEO_PIXEL_SIZE bytes per pixel 541 VIDEO_DATA_FORMAT graphic data format 542 (0-5, cf. cfb_console.c) 543 VIDEO_FB_ADRS framebuffer address 544 VIDEO_KBD_INIT_FCT keyboard int fct 545 (i.e. i8042_kbd_init()) 546 VIDEO_TSTC_FCT test char fct 547 (i.e. i8042_tstc) 548 VIDEO_GETC_FCT get char fct 549 (i.e. i8042_getc) 550 CONFIG_CONSOLE_CURSOR cursor drawing on/off 551 (requires blink timer 552 cf. i8042.c) 553 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 554 CONFIG_CONSOLE_TIME display time/date info in 555 upper right corner 556 (requires CONFIG_CMD_DATE) 557 CONFIG_VIDEO_LOGO display Linux logo in 558 upper left corner 559 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 560 linux_logo.h for logo. 561 Requires CONFIG_VIDEO_LOGO 562 CONFIG_CONSOLE_EXTRA_INFO 563 additional board info beside 564 the logo 565 566 When CONFIG_CFB_CONSOLE is defined, video console is 567 default i/o. Serial console can be forced with 568 environment 'console=serial'. 569 570 When CONFIG_SILENT_CONSOLE is defined, all console 571 messages (by U-Boot and Linux!) can be silenced with 572 the "silent" environment variable. See 573 doc/README.silent for more information. 574 575- Console Baudrate: 576 CONFIG_BAUDRATE - in bps 577 Select one of the baudrates listed in 578 CONFIG_SYS_BAUDRATE_TABLE, see below. 579 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 580 581- Console Rx buffer length 582 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 583 the maximum receive buffer length for the SMC. 584 This option is actual only for 82xx and 8xx possible. 585 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 586 must be defined, to setup the maximum idle timeout for 587 the SMC. 588 589- Boot Delay: CONFIG_BOOTDELAY - in seconds 590 Delay before automatically booting the default image; 591 set to -1 to disable autoboot. 592 593 See doc/README.autoboot for these options that 594 work with CONFIG_BOOTDELAY. None are required. 595 CONFIG_BOOT_RETRY_TIME 596 CONFIG_BOOT_RETRY_MIN 597 CONFIG_AUTOBOOT_KEYED 598 CONFIG_AUTOBOOT_PROMPT 599 CONFIG_AUTOBOOT_DELAY_STR 600 CONFIG_AUTOBOOT_STOP_STR 601 CONFIG_AUTOBOOT_DELAY_STR2 602 CONFIG_AUTOBOOT_STOP_STR2 603 CONFIG_ZERO_BOOTDELAY_CHECK 604 CONFIG_RESET_TO_RETRY 605 606- Autoboot Command: 607 CONFIG_BOOTCOMMAND 608 Only needed when CONFIG_BOOTDELAY is enabled; 609 define a command string that is automatically executed 610 when no character is read on the console interface 611 within "Boot Delay" after reset. 612 613 CONFIG_BOOTARGS 614 This can be used to pass arguments to the bootm 615 command. The value of CONFIG_BOOTARGS goes into the 616 environment value "bootargs". 617 618 CONFIG_RAMBOOT and CONFIG_NFSBOOT 619 The value of these goes into the environment as 620 "ramboot" and "nfsboot" respectively, and can be used 621 as a convenience, when switching between booting from 622 RAM and NFS. 623 624- Pre-Boot Commands: 625 CONFIG_PREBOOT 626 627 When this option is #defined, the existence of the 628 environment variable "preboot" will be checked 629 immediately before starting the CONFIG_BOOTDELAY 630 countdown and/or running the auto-boot command resp. 631 entering interactive mode. 632 633 This feature is especially useful when "preboot" is 634 automatically generated or modified. For an example 635 see the LWMON board specific code: here "preboot" is 636 modified when the user holds down a certain 637 combination of keys on the (special) keyboard when 638 booting the systems 639 640- Serial Download Echo Mode: 641 CONFIG_LOADS_ECHO 642 If defined to 1, all characters received during a 643 serial download (using the "loads" command) are 644 echoed back. This might be needed by some terminal 645 emulations (like "cu"), but may as well just take 646 time on others. This setting #define's the initial 647 value of the "loads_echo" environment variable. 648 649- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 650 CONFIG_KGDB_BAUDRATE 651 Select one of the baudrates listed in 652 CONFIG_SYS_BAUDRATE_TABLE, see below. 653 654- Monitor Functions: 655 Monitor commands can be included or excluded 656 from the build by using the #include files 657 "config_cmd_all.h" and #undef'ing unwanted 658 commands, or using "config_cmd_default.h" 659 and augmenting with additional #define's 660 for wanted commands. 661 662 The default command configuration includes all commands 663 except those marked below with a "*". 664 665 CONFIG_CMD_ASKENV * ask for env variable 666 CONFIG_CMD_BDI bdinfo 667 CONFIG_CMD_BEDBUG * Include BedBug Debugger 668 CONFIG_CMD_BMP * BMP support 669 CONFIG_CMD_BSP * Board specific commands 670 CONFIG_CMD_BOOTD bootd 671 CONFIG_CMD_CACHE * icache, dcache 672 CONFIG_CMD_CONSOLE coninfo 673 CONFIG_CMD_CRC32 * crc32 674 CONFIG_CMD_DATE * support for RTC, date/time... 675 CONFIG_CMD_DHCP * DHCP support 676 CONFIG_CMD_DIAG * Diagnostics 677 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 678 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 679 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 680 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 681 CONFIG_CMD_DTT * Digital Therm and Thermostat 682 CONFIG_CMD_ECHO echo arguments 683 CONFIG_CMD_EDITENV edit env variable 684 CONFIG_CMD_EEPROM * EEPROM read/write support 685 CONFIG_CMD_ELF * bootelf, bootvx 686 CONFIG_CMD_EXPORTENV * export the environment 687 CONFIG_CMD_SAVEENV saveenv 688 CONFIG_CMD_FDC * Floppy Disk Support 689 CONFIG_CMD_FAT * FAT partition support 690 CONFIG_CMD_FDOS * Dos diskette Support 691 CONFIG_CMD_FLASH flinfo, erase, protect 692 CONFIG_CMD_FPGA FPGA device initialization support 693 CONFIG_CMD_GO * the 'go' command (exec code) 694 CONFIG_CMD_GREPENV * search environment 695 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 696 CONFIG_CMD_I2C * I2C serial bus support 697 CONFIG_CMD_IDE * IDE harddisk support 698 CONFIG_CMD_IMI iminfo 699 CONFIG_CMD_IMLS List all found images 700 CONFIG_CMD_IMMAP * IMMR dump support 701 CONFIG_CMD_IMPORTENV * import an environment 702 CONFIG_CMD_IRQ * irqinfo 703 CONFIG_CMD_ITEST Integer/string test of 2 values 704 CONFIG_CMD_JFFS2 * JFFS2 Support 705 CONFIG_CMD_KGDB * kgdb 706 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader) 707 CONFIG_CMD_LOADB loadb 708 CONFIG_CMD_LOADS loads 709 CONFIG_CMD_MD5SUM print md5 message digest 710 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 711 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 712 loop, loopw, mtest 713 CONFIG_CMD_MISC Misc functions like sleep etc 714 CONFIG_CMD_MMC * MMC memory mapped support 715 CONFIG_CMD_MII * MII utility commands 716 CONFIG_CMD_MTDPARTS * MTD partition support 717 CONFIG_CMD_NAND * NAND support 718 CONFIG_CMD_NET bootp, tftpboot, rarpboot 719 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 720 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 721 CONFIG_CMD_PCI * pciinfo 722 CONFIG_CMD_PCMCIA * PCMCIA support 723 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 724 host 725 CONFIG_CMD_PORTIO * Port I/O 726 CONFIG_CMD_REGINFO * Register dump 727 CONFIG_CMD_RUN run command in env variable 728 CONFIG_CMD_SAVES * save S record dump 729 CONFIG_CMD_SCSI * SCSI Support 730 CONFIG_CMD_SDRAM * print SDRAM configuration information 731 (requires CONFIG_CMD_I2C) 732 CONFIG_CMD_SETGETDCR Support for DCR Register access 733 (4xx only) 734 CONFIG_CMD_SHA1SUM print sha1 memory digest 735 (requires CONFIG_CMD_MEMORY) 736 CONFIG_CMD_SOURCE "source" command Support 737 CONFIG_CMD_SPI * SPI serial bus support 738 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 739 CONFIG_CMD_USB * USB support 740 CONFIG_CMD_CDP * Cisco Discover Protocol support 741 CONFIG_CMD_FSL * Microblaze FSL support 742 743 744 EXAMPLE: If you want all functions except of network 745 support you can write: 746 747 #include "config_cmd_all.h" 748 #undef CONFIG_CMD_NET 749 750 Other Commands: 751 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 752 753 Note: Don't enable the "icache" and "dcache" commands 754 (configuration option CONFIG_CMD_CACHE) unless you know 755 what you (and your U-Boot users) are doing. Data 756 cache cannot be enabled on systems like the 8xx or 757 8260 (where accesses to the IMMR region must be 758 uncached), and it cannot be disabled on all other 759 systems where we (mis-) use the data cache to hold an 760 initial stack and some data. 761 762 763 XXX - this list needs to get updated! 764 765- Watchdog: 766 CONFIG_WATCHDOG 767 If this variable is defined, it enables watchdog 768 support for the SoC. There must be support in the SoC 769 specific code for a watchdog. For the 8xx and 8260 770 CPUs, the SIU Watchdog feature is enabled in the SYPCR 771 register. When supported for a specific SoC is 772 available, then no further board specific code should 773 be needed to use it. 774 775 CONFIG_HW_WATCHDOG 776 When using a watchdog circuitry external to the used 777 SoC, then define this variable and provide board 778 specific code for the "hw_watchdog_reset" function. 779 780- U-Boot Version: 781 CONFIG_VERSION_VARIABLE 782 If this variable is defined, an environment variable 783 named "ver" is created by U-Boot showing the U-Boot 784 version as printed by the "version" command. 785 This variable is readonly. 786 787- Real-Time Clock: 788 789 When CONFIG_CMD_DATE is selected, the type of the RTC 790 has to be selected, too. Define exactly one of the 791 following options: 792 793 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 794 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 795 CONFIG_RTC_MC13783 - use MC13783 RTC 796 CONFIG_RTC_MC146818 - use MC146818 RTC 797 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 798 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 799 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 800 CONFIG_RTC_DS164x - use Dallas DS164x RTC 801 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 802 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 803 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 804 CONFIG_SYS_RV3029_TCR - enable trickle charger on 805 RV3029 RTC. 806 807 Note that if the RTC uses I2C, then the I2C interface 808 must also be configured. See I2C Support, below. 809 810- GPIO Support: 811 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 812 CONFIG_PCA953X_INFO - enable pca953x info command 813 814 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 815 chip-ngpio pairs that tell the PCA953X driver the number of 816 pins supported by a particular chip. 817 818 Note that if the GPIO device uses I2C, then the I2C interface 819 must also be configured. See I2C Support, below. 820 821- Timestamp Support: 822 823 When CONFIG_TIMESTAMP is selected, the timestamp 824 (date and time) of an image is printed by image 825 commands like bootm or iminfo. This option is 826 automatically enabled when you select CONFIG_CMD_DATE . 827 828- Partition Support: 829 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 830 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION 831 832 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 833 CONFIG_CMD_SCSI) you must configure support for at 834 least one partition type as well. 835 836- IDE Reset method: 837 CONFIG_IDE_RESET_ROUTINE - this is defined in several 838 board configurations files but used nowhere! 839 840 CONFIG_IDE_RESET - is this is defined, IDE Reset will 841 be performed by calling the function 842 ide_set_reset(int reset) 843 which has to be defined in a board specific file 844 845- ATAPI Support: 846 CONFIG_ATAPI 847 848 Set this to enable ATAPI support. 849 850- LBA48 Support 851 CONFIG_LBA48 852 853 Set this to enable support for disks larger than 137GB 854 Also look at CONFIG_SYS_64BIT_LBA. 855 Whithout these , LBA48 support uses 32bit variables and will 'only' 856 support disks up to 2.1TB. 857 858 CONFIG_SYS_64BIT_LBA: 859 When enabled, makes the IDE subsystem use 64bit sector addresses. 860 Default is 32bit. 861 862- SCSI Support: 863 At the moment only there is only support for the 864 SYM53C8XX SCSI controller; define 865 CONFIG_SCSI_SYM53C8XX to enable it. 866 867 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 868 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 869 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 870 maximum numbers of LUNs, SCSI ID's and target 871 devices. 872 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 873 874- NETWORK Support (PCI): 875 CONFIG_E1000 876 Support for Intel 8254x gigabit chips. 877 878 CONFIG_E1000_FALLBACK_MAC 879 default MAC for empty EEPROM after production. 880 881 CONFIG_EEPRO100 882 Support for Intel 82557/82559/82559ER chips. 883 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 884 write routine for first time initialisation. 885 886 CONFIG_TULIP 887 Support for Digital 2114x chips. 888 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 889 modem chip initialisation (KS8761/QS6611). 890 891 CONFIG_NATSEMI 892 Support for National dp83815 chips. 893 894 CONFIG_NS8382X 895 Support for National dp8382[01] gigabit chips. 896 897- NETWORK Support (other): 898 899 CONFIG_DRIVER_AT91EMAC 900 Support for AT91RM9200 EMAC. 901 902 CONFIG_RMII 903 Define this to use reduced MII inteface 904 905 CONFIG_DRIVER_AT91EMAC_QUIET 906 If this defined, the driver is quiet. 907 The driver doen't show link status messages. 908 909 CONFIG_DRIVER_LAN91C96 910 Support for SMSC's LAN91C96 chips. 911 912 CONFIG_LAN91C96_BASE 913 Define this to hold the physical address 914 of the LAN91C96's I/O space 915 916 CONFIG_LAN91C96_USE_32_BIT 917 Define this to enable 32 bit addressing 918 919 CONFIG_DRIVER_SMC91111 920 Support for SMSC's LAN91C111 chip 921 922 CONFIG_SMC91111_BASE 923 Define this to hold the physical address 924 of the device (I/O space) 925 926 CONFIG_SMC_USE_32_BIT 927 Define this if data bus is 32 bits 928 929 CONFIG_SMC_USE_IOFUNCS 930 Define this to use i/o functions instead of macros 931 (some hardware wont work with macros) 932 933 CONFIG_FTGMAC100 934 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 935 936 CONFIG_FTGMAC100_EGIGA 937 Define this to use GE link update with gigabit PHY. 938 Define this if FTGMAC100 is connected to gigabit PHY. 939 If your system has 10/100 PHY only, it might not occur 940 wrong behavior. Because PHY usually return timeout or 941 useless data when polling gigabit status and gigabit 942 control registers. This behavior won't affect the 943 correctnessof 10/100 link speed update. 944 945 CONFIG_SMC911X 946 Support for SMSC's LAN911x and LAN921x chips 947 948 CONFIG_SMC911X_BASE 949 Define this to hold the physical address 950 of the device (I/O space) 951 952 CONFIG_SMC911X_32_BIT 953 Define this if data bus is 32 bits 954 955 CONFIG_SMC911X_16_BIT 956 Define this if data bus is 16 bits. If your processor 957 automatically converts one 32 bit word to two 16 bit 958 words you may also try CONFIG_SMC911X_32_BIT. 959 960 CONFIG_SH_ETHER 961 Support for Renesas on-chip Ethernet controller 962 963 CONFIG_SH_ETHER_USE_PORT 964 Define the number of ports to be used 965 966 CONFIG_SH_ETHER_PHY_ADDR 967 Define the ETH PHY's address 968 969 CONFIG_SH_ETHER_CACHE_WRITEBACK 970 If this option is set, the driver enables cache flush. 971 972- USB Support: 973 At the moment only the UHCI host controller is 974 supported (PIP405, MIP405, MPC5200); define 975 CONFIG_USB_UHCI to enable it. 976 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 977 and define CONFIG_USB_STORAGE to enable the USB 978 storage devices. 979 Note: 980 Supported are USB Keyboards and USB Floppy drives 981 (TEAC FD-05PUB). 982 MPC5200 USB requires additional defines: 983 CONFIG_USB_CLOCK 984 for 528 MHz Clock: 0x0001bbbb 985 CONFIG_PSC3_USB 986 for USB on PSC3 987 CONFIG_USB_CONFIG 988 for differential drivers: 0x00001000 989 for single ended drivers: 0x00005000 990 for differential drivers on PSC3: 0x00000100 991 for single ended drivers on PSC3: 0x00004100 992 CONFIG_SYS_USB_EVENT_POLL 993 May be defined to allow interrupt polling 994 instead of using asynchronous interrupts 995 996- USB Device: 997 Define the below if you wish to use the USB console. 998 Once firmware is rebuilt from a serial console issue the 999 command "setenv stdin usbtty; setenv stdout usbtty" and 1000 attach your USB cable. The Unix command "dmesg" should print 1001 it has found a new device. The environment variable usbtty 1002 can be set to gserial or cdc_acm to enable your device to 1003 appear to a USB host as a Linux gserial device or a 1004 Common Device Class Abstract Control Model serial device. 1005 If you select usbtty = gserial you should be able to enumerate 1006 a Linux host by 1007 # modprobe usbserial vendor=0xVendorID product=0xProductID 1008 else if using cdc_acm, simply setting the environment 1009 variable usbtty to be cdc_acm should suffice. The following 1010 might be defined in YourBoardName.h 1011 1012 CONFIG_USB_DEVICE 1013 Define this to build a UDC device 1014 1015 CONFIG_USB_TTY 1016 Define this to have a tty type of device available to 1017 talk to the UDC device 1018 1019 CONFIG_SYS_CONSOLE_IS_IN_ENV 1020 Define this if you want stdin, stdout &/or stderr to 1021 be set to usbtty. 1022 1023 mpc8xx: 1024 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1025 Derive USB clock from external clock "blah" 1026 - CONFIG_SYS_USB_EXTC_CLK 0x02 1027 1028 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1029 Derive USB clock from brgclk 1030 - CONFIG_SYS_USB_BRG_CLK 0x04 1031 1032 If you have a USB-IF assigned VendorID then you may wish to 1033 define your own vendor specific values either in BoardName.h 1034 or directly in usbd_vendor_info.h. If you don't define 1035 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1036 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1037 should pretend to be a Linux device to it's target host. 1038 1039 CONFIG_USBD_MANUFACTURER 1040 Define this string as the name of your company for 1041 - CONFIG_USBD_MANUFACTURER "my company" 1042 1043 CONFIG_USBD_PRODUCT_NAME 1044 Define this string as the name of your product 1045 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1046 1047 CONFIG_USBD_VENDORID 1048 Define this as your assigned Vendor ID from the USB 1049 Implementors Forum. This *must* be a genuine Vendor ID 1050 to avoid polluting the USB namespace. 1051 - CONFIG_USBD_VENDORID 0xFFFF 1052 1053 CONFIG_USBD_PRODUCTID 1054 Define this as the unique Product ID 1055 for your device 1056 - CONFIG_USBD_PRODUCTID 0xFFFF 1057 1058 1059- MMC Support: 1060 The MMC controller on the Intel PXA is supported. To 1061 enable this define CONFIG_MMC. The MMC can be 1062 accessed from the boot prompt by mapping the device 1063 to physical memory similar to flash. Command line is 1064 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1065 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1066 1067 CONFIG_SH_MMCIF 1068 Support for Renesas on-chip MMCIF controller 1069 1070 CONFIG_SH_MMCIF_ADDR 1071 Define the base address of MMCIF registers 1072 1073 CONFIG_SH_MMCIF_CLK 1074 Define the clock frequency for MMCIF 1075 1076- Journaling Flash filesystem support: 1077 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1078 CONFIG_JFFS2_NAND_DEV 1079 Define these for a default partition on a NAND device 1080 1081 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1082 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1083 Define these for a default partition on a NOR device 1084 1085 CONFIG_SYS_JFFS_CUSTOM_PART 1086 Define this to create an own partition. You have to provide a 1087 function struct part_info* jffs2_part_info(int part_num) 1088 1089 If you define only one JFFS2 partition you may also want to 1090 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1091 to disable the command chpart. This is the default when you 1092 have not defined a custom partition 1093 1094- Keyboard Support: 1095 CONFIG_ISA_KEYBOARD 1096 1097 Define this to enable standard (PC-Style) keyboard 1098 support 1099 1100 CONFIG_I8042_KBD 1101 Standard PC keyboard driver with US (is default) and 1102 GERMAN key layout (switch via environment 'keymap=de') support. 1103 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1104 for cfb_console. Supports cursor blinking. 1105 1106- Video support: 1107 CONFIG_VIDEO 1108 1109 Define this to enable video support (for output to 1110 video). 1111 1112 CONFIG_VIDEO_CT69000 1113 1114 Enable Chips & Technologies 69000 Video chip 1115 1116 CONFIG_VIDEO_SMI_LYNXEM 1117 Enable Silicon Motion SMI 712/710/810 Video chip. The 1118 video output is selected via environment 'videoout' 1119 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1120 assumed. 1121 1122 For the CT69000 and SMI_LYNXEM drivers, videomode is 1123 selected via environment 'videomode'. Two different ways 1124 are possible: 1125 - "videomode=num" 'num' is a standard LiLo mode numbers. 1126 Following standard modes are supported (* is default): 1127 1128 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1129 -------------+--------------------------------------------- 1130 8 bits | 0x301* 0x303 0x305 0x161 0x307 1131 15 bits | 0x310 0x313 0x316 0x162 0x319 1132 16 bits | 0x311 0x314 0x317 0x163 0x31A 1133 24 bits | 0x312 0x315 0x318 ? 0x31B 1134 -------------+--------------------------------------------- 1135 (i.e. setenv videomode 317; saveenv; reset;) 1136 1137 - "videomode=bootargs" all the video parameters are parsed 1138 from the bootargs. (See drivers/video/videomodes.c) 1139 1140 1141 CONFIG_VIDEO_SED13806 1142 Enable Epson SED13806 driver. This driver supports 8bpp 1143 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1144 or CONFIG_VIDEO_SED13806_16BPP 1145 1146 CONFIG_FSL_DIU_FB 1147 Enable the Freescale DIU video driver. Reference boards for 1148 SOCs that have a DIU should define this macro to enable DIU 1149 support, and should also define these other macros: 1150 1151 CONFIG_SYS_DIU_ADDR 1152 CONFIG_VIDEO 1153 CONFIG_CMD_BMP 1154 CONFIG_CFB_CONSOLE 1155 CONFIG_VIDEO_SW_CURSOR 1156 CONFIG_VGA_AS_SINGLE_DEVICE 1157 CONFIG_VIDEO_LOGO 1158 CONFIG_VIDEO_BMP_LOGO 1159 1160 The DIU driver will look for the 'video-mode' environment 1161 variable, and if defined, enable the DIU as a console during 1162 boot. See the documentation file README.video for a 1163 description of this variable. 1164 1165- Keyboard Support: 1166 CONFIG_KEYBOARD 1167 1168 Define this to enable a custom keyboard support. 1169 This simply calls drv_keyboard_init() which must be 1170 defined in your board-specific files. 1171 The only board using this so far is RBC823. 1172 1173- LCD Support: CONFIG_LCD 1174 1175 Define this to enable LCD support (for output to LCD 1176 display); also select one of the supported displays 1177 by defining one of these: 1178 1179 CONFIG_ATMEL_LCD: 1180 1181 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1182 1183 CONFIG_NEC_NL6448AC33: 1184 1185 NEC NL6448AC33-18. Active, color, single scan. 1186 1187 CONFIG_NEC_NL6448BC20 1188 1189 NEC NL6448BC20-08. 6.5", 640x480. 1190 Active, color, single scan. 1191 1192 CONFIG_NEC_NL6448BC33_54 1193 1194 NEC NL6448BC33-54. 10.4", 640x480. 1195 Active, color, single scan. 1196 1197 CONFIG_SHARP_16x9 1198 1199 Sharp 320x240. Active, color, single scan. 1200 It isn't 16x9, and I am not sure what it is. 1201 1202 CONFIG_SHARP_LQ64D341 1203 1204 Sharp LQ64D341 display, 640x480. 1205 Active, color, single scan. 1206 1207 CONFIG_HLD1045 1208 1209 HLD1045 display, 640x480. 1210 Active, color, single scan. 1211 1212 CONFIG_OPTREX_BW 1213 1214 Optrex CBL50840-2 NF-FW 99 22 M5 1215 or 1216 Hitachi LMG6912RPFC-00T 1217 or 1218 Hitachi SP14Q002 1219 1220 320x240. Black & white. 1221 1222 Normally display is black on white background; define 1223 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1224 1225- Splash Screen Support: CONFIG_SPLASH_SCREEN 1226 1227 If this option is set, the environment is checked for 1228 a variable "splashimage". If found, the usual display 1229 of logo, copyright and system information on the LCD 1230 is suppressed and the BMP image at the address 1231 specified in "splashimage" is loaded instead. The 1232 console is redirected to the "nulldev", too. This 1233 allows for a "silent" boot where a splash screen is 1234 loaded very quickly after power-on. 1235 1236 CONFIG_SPLASH_SCREEN_ALIGN 1237 1238 If this option is set the splash image can be freely positioned 1239 on the screen. Environment variable "splashpos" specifies the 1240 position as "x,y". If a positive number is given it is used as 1241 number of pixel from left/top. If a negative number is given it 1242 is used as number of pixel from right/bottom. You can also 1243 specify 'm' for centering the image. 1244 1245 Example: 1246 setenv splashpos m,m 1247 => image at center of screen 1248 1249 setenv splashpos 30,20 1250 => image at x = 30 and y = 20 1251 1252 setenv splashpos -10,m 1253 => vertically centered image 1254 at x = dspWidth - bmpWidth - 9 1255 1256- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1257 1258 If this option is set, additionally to standard BMP 1259 images, gzipped BMP images can be displayed via the 1260 splashscreen support or the bmp command. 1261 1262- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1263 1264 If this option is set, 8-bit RLE compressed BMP images 1265 can be displayed via the splashscreen support or the 1266 bmp command. 1267 1268- Compression support: 1269 CONFIG_BZIP2 1270 1271 If this option is set, support for bzip2 compressed 1272 images is included. If not, only uncompressed and gzip 1273 compressed images are supported. 1274 1275 NOTE: the bzip2 algorithm requires a lot of RAM, so 1276 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1277 be at least 4MB. 1278 1279 CONFIG_LZMA 1280 1281 If this option is set, support for lzma compressed 1282 images is included. 1283 1284 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1285 requires an amount of dynamic memory that is given by the 1286 formula: 1287 1288 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1289 1290 Where lc and lp stand for, respectively, Literal context bits 1291 and Literal pos bits. 1292 1293 This value is upper-bounded by 14MB in the worst case. Anyway, 1294 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1295 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1296 a very small buffer. 1297 1298 Use the lzmainfo tool to determinate the lc and lp values and 1299 then calculate the amount of needed dynamic memory (ensuring 1300 the appropriate CONFIG_SYS_MALLOC_LEN value). 1301 1302- MII/PHY support: 1303 CONFIG_PHY_ADDR 1304 1305 The address of PHY on MII bus. 1306 1307 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1308 1309 The clock frequency of the MII bus 1310 1311 CONFIG_PHY_GIGE 1312 1313 If this option is set, support for speed/duplex 1314 detection of gigabit PHY is included. 1315 1316 CONFIG_PHY_RESET_DELAY 1317 1318 Some PHY like Intel LXT971A need extra delay after 1319 reset before any MII register access is possible. 1320 For such PHY, set this option to the usec delay 1321 required. (minimum 300usec for LXT971A) 1322 1323 CONFIG_PHY_CMD_DELAY (ppc4xx) 1324 1325 Some PHY like Intel LXT971A need extra delay after 1326 command issued before MII status register can be read 1327 1328- Ethernet address: 1329 CONFIG_ETHADDR 1330 CONFIG_ETH1ADDR 1331 CONFIG_ETH2ADDR 1332 CONFIG_ETH3ADDR 1333 CONFIG_ETH4ADDR 1334 CONFIG_ETH5ADDR 1335 1336 Define a default value for Ethernet address to use 1337 for the respective Ethernet interface, in case this 1338 is not determined automatically. 1339 1340- IP address: 1341 CONFIG_IPADDR 1342 1343 Define a default value for the IP address to use for 1344 the default Ethernet interface, in case this is not 1345 determined through e.g. bootp. 1346 1347- Server IP address: 1348 CONFIG_SERVERIP 1349 1350 Defines a default value for the IP address of a TFTP 1351 server to contact when using the "tftboot" command. 1352 1353 CONFIG_KEEP_SERVERADDR 1354 1355 Keeps the server's MAC address, in the env 'serveraddr' 1356 for passing to bootargs (like Linux's netconsole option) 1357 1358- Multicast TFTP Mode: 1359 CONFIG_MCAST_TFTP 1360 1361 Defines whether you want to support multicast TFTP as per 1362 rfc-2090; for example to work with atftp. Lets lots of targets 1363 tftp down the same boot image concurrently. Note: the Ethernet 1364 driver in use must provide a function: mcast() to join/leave a 1365 multicast group. 1366 1367- BOOTP Recovery Mode: 1368 CONFIG_BOOTP_RANDOM_DELAY 1369 1370 If you have many targets in a network that try to 1371 boot using BOOTP, you may want to avoid that all 1372 systems send out BOOTP requests at precisely the same 1373 moment (which would happen for instance at recovery 1374 from a power failure, when all systems will try to 1375 boot, thus flooding the BOOTP server. Defining 1376 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1377 inserted before sending out BOOTP requests. The 1378 following delays are inserted then: 1379 1380 1st BOOTP request: delay 0 ... 1 sec 1381 2nd BOOTP request: delay 0 ... 2 sec 1382 3rd BOOTP request: delay 0 ... 4 sec 1383 4th and following 1384 BOOTP requests: delay 0 ... 8 sec 1385 1386- DHCP Advanced Options: 1387 You can fine tune the DHCP functionality by defining 1388 CONFIG_BOOTP_* symbols: 1389 1390 CONFIG_BOOTP_SUBNETMASK 1391 CONFIG_BOOTP_GATEWAY 1392 CONFIG_BOOTP_HOSTNAME 1393 CONFIG_BOOTP_NISDOMAIN 1394 CONFIG_BOOTP_BOOTPATH 1395 CONFIG_BOOTP_BOOTFILESIZE 1396 CONFIG_BOOTP_DNS 1397 CONFIG_BOOTP_DNS2 1398 CONFIG_BOOTP_SEND_HOSTNAME 1399 CONFIG_BOOTP_NTPSERVER 1400 CONFIG_BOOTP_TIMEOFFSET 1401 CONFIG_BOOTP_VENDOREX 1402 1403 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1404 environment variable, not the BOOTP server. 1405 1406 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1407 serverip from a DHCP server, it is possible that more 1408 than one DNS serverip is offered to the client. 1409 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1410 serverip will be stored in the additional environment 1411 variable "dnsip2". The first DNS serverip is always 1412 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1413 is defined. 1414 1415 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1416 to do a dynamic update of a DNS server. To do this, they 1417 need the hostname of the DHCP requester. 1418 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1419 of the "hostname" environment variable is passed as 1420 option 12 to the DHCP server. 1421 1422 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1423 1424 A 32bit value in microseconds for a delay between 1425 receiving a "DHCP Offer" and sending the "DHCP Request". 1426 This fixes a problem with certain DHCP servers that don't 1427 respond 100% of the time to a "DHCP request". E.g. On an 1428 AT91RM9200 processor running at 180MHz, this delay needed 1429 to be *at least* 15,000 usec before a Windows Server 2003 1430 DHCP server would reply 100% of the time. I recommend at 1431 least 50,000 usec to be safe. The alternative is to hope 1432 that one of the retries will be successful but note that 1433 the DHCP timeout and retry process takes a longer than 1434 this delay. 1435 1436 - CDP Options: 1437 CONFIG_CDP_DEVICE_ID 1438 1439 The device id used in CDP trigger frames. 1440 1441 CONFIG_CDP_DEVICE_ID_PREFIX 1442 1443 A two character string which is prefixed to the MAC address 1444 of the device. 1445 1446 CONFIG_CDP_PORT_ID 1447 1448 A printf format string which contains the ascii name of 1449 the port. Normally is set to "eth%d" which sets 1450 eth0 for the first Ethernet, eth1 for the second etc. 1451 1452 CONFIG_CDP_CAPABILITIES 1453 1454 A 32bit integer which indicates the device capabilities; 1455 0x00000010 for a normal host which does not forwards. 1456 1457 CONFIG_CDP_VERSION 1458 1459 An ascii string containing the version of the software. 1460 1461 CONFIG_CDP_PLATFORM 1462 1463 An ascii string containing the name of the platform. 1464 1465 CONFIG_CDP_TRIGGER 1466 1467 A 32bit integer sent on the trigger. 1468 1469 CONFIG_CDP_POWER_CONSUMPTION 1470 1471 A 16bit integer containing the power consumption of the 1472 device in .1 of milliwatts. 1473 1474 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1475 1476 A byte containing the id of the VLAN. 1477 1478- Status LED: CONFIG_STATUS_LED 1479 1480 Several configurations allow to display the current 1481 status using a LED. For instance, the LED will blink 1482 fast while running U-Boot code, stop blinking as 1483 soon as a reply to a BOOTP request was received, and 1484 start blinking slow once the Linux kernel is running 1485 (supported by a status LED driver in the Linux 1486 kernel). Defining CONFIG_STATUS_LED enables this 1487 feature in U-Boot. 1488 1489- CAN Support: CONFIG_CAN_DRIVER 1490 1491 Defining CONFIG_CAN_DRIVER enables CAN driver support 1492 on those systems that support this (optional) 1493 feature, like the TQM8xxL modules. 1494 1495- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1496 1497 These enable I2C serial bus commands. Defining either of 1498 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1499 include the appropriate I2C driver for the selected CPU. 1500 1501 This will allow you to use i2c commands at the u-boot 1502 command line (as long as you set CONFIG_CMD_I2C in 1503 CONFIG_COMMANDS) and communicate with i2c based realtime 1504 clock chips. See common/cmd_i2c.c for a description of the 1505 command line interface. 1506 1507 CONFIG_HARD_I2C selects a hardware I2C controller. 1508 1509 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1510 bit-banging) driver instead of CPM or similar hardware 1511 support for I2C. 1512 1513 There are several other quantities that must also be 1514 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1515 1516 In both cases you will need to define CONFIG_SYS_I2C_SPEED 1517 to be the frequency (in Hz) at which you wish your i2c bus 1518 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 1519 the CPU's i2c node address). 1520 1521 Now, the u-boot i2c code for the mpc8xx 1522 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 1523 and so its address should therefore be cleared to 0 (See, 1524 eg, MPC823e User's Manual p.16-473). So, set 1525 CONFIG_SYS_I2C_SLAVE to 0. 1526 1527 CONFIG_SYS_I2C_INIT_MPC5XXX 1528 1529 When a board is reset during an i2c bus transfer 1530 chips might think that the current transfer is still 1531 in progress. Reset the slave devices by sending start 1532 commands until the slave device responds. 1533 1534 That's all that's required for CONFIG_HARD_I2C. 1535 1536 If you use the software i2c interface (CONFIG_SOFT_I2C) 1537 then the following macros need to be defined (examples are 1538 from include/configs/lwmon.h): 1539 1540 I2C_INIT 1541 1542 (Optional). Any commands necessary to enable the I2C 1543 controller or configure ports. 1544 1545 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1546 1547 I2C_PORT 1548 1549 (Only for MPC8260 CPU). The I/O port to use (the code 1550 assumes both bits are on the same port). Valid values 1551 are 0..3 for ports A..D. 1552 1553 I2C_ACTIVE 1554 1555 The code necessary to make the I2C data line active 1556 (driven). If the data line is open collector, this 1557 define can be null. 1558 1559 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1560 1561 I2C_TRISTATE 1562 1563 The code necessary to make the I2C data line tri-stated 1564 (inactive). If the data line is open collector, this 1565 define can be null. 1566 1567 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1568 1569 I2C_READ 1570 1571 Code that returns TRUE if the I2C data line is high, 1572 FALSE if it is low. 1573 1574 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1575 1576 I2C_SDA(bit) 1577 1578 If <bit> is TRUE, sets the I2C data line high. If it 1579 is FALSE, it clears it (low). 1580 1581 eg: #define I2C_SDA(bit) \ 1582 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1583 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1584 1585 I2C_SCL(bit) 1586 1587 If <bit> is TRUE, sets the I2C clock line high. If it 1588 is FALSE, it clears it (low). 1589 1590 eg: #define I2C_SCL(bit) \ 1591 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1592 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1593 1594 I2C_DELAY 1595 1596 This delay is invoked four times per clock cycle so this 1597 controls the rate of data transfer. The data rate thus 1598 is 1 / (I2C_DELAY * 4). Often defined to be something 1599 like: 1600 1601 #define I2C_DELAY udelay(2) 1602 1603 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 1604 1605 If your arch supports the generic GPIO framework (asm/gpio.h), 1606 then you may alternatively define the two GPIOs that are to be 1607 used as SCL / SDA. Any of the previous I2C_xxx macros will 1608 have GPIO-based defaults assigned to them as appropriate. 1609 1610 You should define these to the GPIO value as given directly to 1611 the generic GPIO functions. 1612 1613 CONFIG_SYS_I2C_INIT_BOARD 1614 1615 When a board is reset during an i2c bus transfer 1616 chips might think that the current transfer is still 1617 in progress. On some boards it is possible to access 1618 the i2c SCLK line directly, either by using the 1619 processor pin as a GPIO or by having a second pin 1620 connected to the bus. If this option is defined a 1621 custom i2c_init_board() routine in boards/xxx/board.c 1622 is run early in the boot sequence. 1623 1624 CONFIG_SYS_I2C_BOARD_LATE_INIT 1625 1626 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 1627 defined a custom i2c_board_late_init() routine in 1628 boards/xxx/board.c is run AFTER the operations in i2c_init() 1629 is completed. This callpoint can be used to unreset i2c bus 1630 using CPU i2c controller register accesses for CPUs whose i2c 1631 controller provide such a method. It is called at the end of 1632 i2c_init() to allow i2c_init operations to setup the i2c bus 1633 controller on the CPU (e.g. setting bus speed & slave address). 1634 1635 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1636 1637 This option enables configuration of bi_iic_fast[] flags 1638 in u-boot bd_info structure based on u-boot environment 1639 variable "i2cfast". (see also i2cfast) 1640 1641 CONFIG_I2C_MULTI_BUS 1642 1643 This option allows the use of multiple I2C buses, each of which 1644 must have a controller. At any point in time, only one bus is 1645 active. To switch to a different bus, use the 'i2c dev' command. 1646 Note that bus numbering is zero-based. 1647 1648 CONFIG_SYS_I2C_NOPROBES 1649 1650 This option specifies a list of I2C devices that will be skipped 1651 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 1652 is set, specify a list of bus-device pairs. Otherwise, specify 1653 a 1D array of device addresses 1654 1655 e.g. 1656 #undef CONFIG_I2C_MULTI_BUS 1657 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 1658 1659 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1660 1661 #define CONFIG_I2C_MULTI_BUS 1662 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1663 1664 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1665 1666 CONFIG_SYS_SPD_BUS_NUM 1667 1668 If defined, then this indicates the I2C bus number for DDR SPD. 1669 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1670 1671 CONFIG_SYS_RTC_BUS_NUM 1672 1673 If defined, then this indicates the I2C bus number for the RTC. 1674 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1675 1676 CONFIG_SYS_DTT_BUS_NUM 1677 1678 If defined, then this indicates the I2C bus number for the DTT. 1679 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1680 1681 CONFIG_SYS_I2C_DTT_ADDR: 1682 1683 If defined, specifies the I2C address of the DTT device. 1684 If not defined, then U-Boot uses predefined value for 1685 specified DTT device. 1686 1687 CONFIG_FSL_I2C 1688 1689 Define this option if you want to use Freescale's I2C driver in 1690 drivers/i2c/fsl_i2c.c. 1691 1692 CONFIG_I2C_MUX 1693 1694 Define this option if you have I2C devices reached over 1 .. n 1695 I2C Muxes like the pca9544a. This option addes a new I2C 1696 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a 1697 new I2C Bus to the existing I2C Busses. If you select the 1698 new Bus with "i2c dev", u-bbot sends first the commandos for 1699 the muxes to activate this new "bus". 1700 1701 CONFIG_I2C_MULTI_BUS must be also defined, to use this 1702 feature! 1703 1704 Example: 1705 Adding a new I2C Bus reached over 2 pca9544a muxes 1706 The First mux with address 70 and channel 6 1707 The Second mux with address 71 and channel 4 1708 1709 => i2c bus pca9544a:70:6:pca9544a:71:4 1710 1711 Use the "i2c bus" command without parameter, to get a list 1712 of I2C Busses with muxes: 1713 1714 => i2c bus 1715 Busses reached over muxes: 1716 Bus ID: 2 1717 reached over Mux(es): 1718 pca9544a@70 ch: 4 1719 Bus ID: 3 1720 reached over Mux(es): 1721 pca9544a@70 ch: 6 1722 pca9544a@71 ch: 4 1723 => 1724 1725 If you now switch to the new I2C Bus 3 with "i2c dev 3" 1726 u-boot sends First the Commando to the mux@70 to enable 1727 channel 6, and then the Commando to the mux@71 to enable 1728 the channel 4. 1729 1730 After that, you can use the "normal" i2c commands as 1731 usual, to communicate with your I2C devices behind 1732 the 2 muxes. 1733 1734 This option is actually implemented for the bitbanging 1735 algorithm in common/soft_i2c.c and for the Hardware I2C 1736 Bus on the MPC8260. But it should be not so difficult 1737 to add this option to other architectures. 1738 1739 CONFIG_SOFT_I2C_READ_REPEATED_START 1740 1741 defining this will force the i2c_read() function in 1742 the soft_i2c driver to perform an I2C repeated start 1743 between writing the address pointer and reading the 1744 data. If this define is omitted the default behaviour 1745 of doing a stop-start sequence will be used. Most I2C 1746 devices can use either method, but some require one or 1747 the other. 1748 1749- SPI Support: CONFIG_SPI 1750 1751 Enables SPI driver (so far only tested with 1752 SPI EEPROM, also an instance works with Crystal A/D and 1753 D/As on the SACSng board) 1754 1755 CONFIG_SH_SPI 1756 1757 Enables the driver for SPI controller on SuperH. Currently 1758 only SH7757 is supported. 1759 1760 CONFIG_SPI_X 1761 1762 Enables extended (16-bit) SPI EEPROM addressing. 1763 (symmetrical to CONFIG_I2C_X) 1764 1765 CONFIG_SOFT_SPI 1766 1767 Enables a software (bit-bang) SPI driver rather than 1768 using hardware support. This is a general purpose 1769 driver that only requires three general I/O port pins 1770 (two outputs, one input) to function. If this is 1771 defined, the board configuration must define several 1772 SPI configuration items (port pins to use, etc). For 1773 an example, see include/configs/sacsng.h. 1774 1775 CONFIG_HARD_SPI 1776 1777 Enables a hardware SPI driver for general-purpose reads 1778 and writes. As with CONFIG_SOFT_SPI, the board configuration 1779 must define a list of chip-select function pointers. 1780 Currently supported on some MPC8xxx processors. For an 1781 example, see include/configs/mpc8349emds.h. 1782 1783 CONFIG_MXC_SPI 1784 1785 Enables the driver for the SPI controllers on i.MX and MXC 1786 SoCs. Currently only i.MX31 is supported. 1787 1788- FPGA Support: CONFIG_FPGA 1789 1790 Enables FPGA subsystem. 1791 1792 CONFIG_FPGA_<vendor> 1793 1794 Enables support for specific chip vendors. 1795 (ALTERA, XILINX) 1796 1797 CONFIG_FPGA_<family> 1798 1799 Enables support for FPGA family. 1800 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1801 1802 CONFIG_FPGA_COUNT 1803 1804 Specify the number of FPGA devices to support. 1805 1806 CONFIG_SYS_FPGA_PROG_FEEDBACK 1807 1808 Enable printing of hash marks during FPGA configuration. 1809 1810 CONFIG_SYS_FPGA_CHECK_BUSY 1811 1812 Enable checks on FPGA configuration interface busy 1813 status by the configuration function. This option 1814 will require a board or device specific function to 1815 be written. 1816 1817 CONFIG_FPGA_DELAY 1818 1819 If defined, a function that provides delays in the FPGA 1820 configuration driver. 1821 1822 CONFIG_SYS_FPGA_CHECK_CTRLC 1823 Allow Control-C to interrupt FPGA configuration 1824 1825 CONFIG_SYS_FPGA_CHECK_ERROR 1826 1827 Check for configuration errors during FPGA bitfile 1828 loading. For example, abort during Virtex II 1829 configuration if the INIT_B line goes low (which 1830 indicated a CRC error). 1831 1832 CONFIG_SYS_FPGA_WAIT_INIT 1833 1834 Maximum time to wait for the INIT_B line to deassert 1835 after PROB_B has been deasserted during a Virtex II 1836 FPGA configuration sequence. The default time is 500 1837 ms. 1838 1839 CONFIG_SYS_FPGA_WAIT_BUSY 1840 1841 Maximum time to wait for BUSY to deassert during 1842 Virtex II FPGA configuration. The default is 5 ms. 1843 1844 CONFIG_SYS_FPGA_WAIT_CONFIG 1845 1846 Time to wait after FPGA configuration. The default is 1847 200 ms. 1848 1849- Configuration Management: 1850 CONFIG_IDENT_STRING 1851 1852 If defined, this string will be added to the U-Boot 1853 version information (U_BOOT_VERSION) 1854 1855- Vendor Parameter Protection: 1856 1857 U-Boot considers the values of the environment 1858 variables "serial#" (Board Serial Number) and 1859 "ethaddr" (Ethernet Address) to be parameters that 1860 are set once by the board vendor / manufacturer, and 1861 protects these variables from casual modification by 1862 the user. Once set, these variables are read-only, 1863 and write or delete attempts are rejected. You can 1864 change this behaviour: 1865 1866 If CONFIG_ENV_OVERWRITE is #defined in your config 1867 file, the write protection for vendor parameters is 1868 completely disabled. Anybody can change or delete 1869 these parameters. 1870 1871 Alternatively, if you #define _both_ CONFIG_ETHADDR 1872 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1873 Ethernet address is installed in the environment, 1874 which can be changed exactly ONCE by the user. [The 1875 serial# is unaffected by this, i. e. it remains 1876 read-only.] 1877 1878- Protected RAM: 1879 CONFIG_PRAM 1880 1881 Define this variable to enable the reservation of 1882 "protected RAM", i. e. RAM which is not overwritten 1883 by U-Boot. Define CONFIG_PRAM to hold the number of 1884 kB you want to reserve for pRAM. You can overwrite 1885 this default value by defining an environment 1886 variable "pram" to the number of kB you want to 1887 reserve. Note that the board info structure will 1888 still show the full amount of RAM. If pRAM is 1889 reserved, a new environment variable "mem" will 1890 automatically be defined to hold the amount of 1891 remaining RAM in a form that can be passed as boot 1892 argument to Linux, for instance like that: 1893 1894 setenv bootargs ... mem=\${mem} 1895 saveenv 1896 1897 This way you can tell Linux not to use this memory, 1898 either, which results in a memory region that will 1899 not be affected by reboots. 1900 1901 *WARNING* If your board configuration uses automatic 1902 detection of the RAM size, you must make sure that 1903 this memory test is non-destructive. So far, the 1904 following board configurations are known to be 1905 "pRAM-clean": 1906 1907 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1908 HERMES, IP860, RPXlite, LWMON, LANTEC, 1909 FLAGADM, TQM8260 1910 1911- Error Recovery: 1912 CONFIG_PANIC_HANG 1913 1914 Define this variable to stop the system in case of a 1915 fatal error, so that you have to reset it manually. 1916 This is probably NOT a good idea for an embedded 1917 system where you want the system to reboot 1918 automatically as fast as possible, but it may be 1919 useful during development since you can try to debug 1920 the conditions that lead to the situation. 1921 1922 CONFIG_NET_RETRY_COUNT 1923 1924 This variable defines the number of retries for 1925 network operations like ARP, RARP, TFTP, or BOOTP 1926 before giving up the operation. If not defined, a 1927 default value of 5 is used. 1928 1929 CONFIG_ARP_TIMEOUT 1930 1931 Timeout waiting for an ARP reply in milliseconds. 1932 1933- Command Interpreter: 1934 CONFIG_AUTO_COMPLETE 1935 1936 Enable auto completion of commands using TAB. 1937 1938 Note that this feature has NOT been implemented yet 1939 for the "hush" shell. 1940 1941 1942 CONFIG_SYS_HUSH_PARSER 1943 1944 Define this variable to enable the "hush" shell (from 1945 Busybox) as command line interpreter, thus enabling 1946 powerful command line syntax like 1947 if...then...else...fi conditionals or `&&' and '||' 1948 constructs ("shell scripts"). 1949 1950 If undefined, you get the old, much simpler behaviour 1951 with a somewhat smaller memory footprint. 1952 1953 1954 CONFIG_SYS_PROMPT_HUSH_PS2 1955 1956 This defines the secondary prompt string, which is 1957 printed when the command interpreter needs more input 1958 to complete a command. Usually "> ". 1959 1960 Note: 1961 1962 In the current implementation, the local variables 1963 space and global environment variables space are 1964 separated. Local variables are those you define by 1965 simply typing `name=value'. To access a local 1966 variable later on, you have write `$name' or 1967 `${name}'; to execute the contents of a variable 1968 directly type `$name' at the command prompt. 1969 1970 Global environment variables are those you use 1971 setenv/printenv to work with. To run a command stored 1972 in such a variable, you need to use the run command, 1973 and you must not use the '$' sign to access them. 1974 1975 To store commands and special characters in a 1976 variable, please use double quotation marks 1977 surrounding the whole text of the variable, instead 1978 of the backslashes before semicolons and special 1979 symbols. 1980 1981- Commandline Editing and History: 1982 CONFIG_CMDLINE_EDITING 1983 1984 Enable editing and History functions for interactive 1985 commandline input operations 1986 1987- Default Environment: 1988 CONFIG_EXTRA_ENV_SETTINGS 1989 1990 Define this to contain any number of null terminated 1991 strings (variable = value pairs) that will be part of 1992 the default environment compiled into the boot image. 1993 1994 For example, place something like this in your 1995 board's config file: 1996 1997 #define CONFIG_EXTRA_ENV_SETTINGS \ 1998 "myvar1=value1\0" \ 1999 "myvar2=value2\0" 2000 2001 Warning: This method is based on knowledge about the 2002 internal format how the environment is stored by the 2003 U-Boot code. This is NOT an official, exported 2004 interface! Although it is unlikely that this format 2005 will change soon, there is no guarantee either. 2006 You better know what you are doing here. 2007 2008 Note: overly (ab)use of the default environment is 2009 discouraged. Make sure to check other ways to preset 2010 the environment like the "source" command or the 2011 boot command first. 2012 2013- DataFlash Support: 2014 CONFIG_HAS_DATAFLASH 2015 2016 Defining this option enables DataFlash features and 2017 allows to read/write in Dataflash via the standard 2018 commands cp, md... 2019 2020- SystemACE Support: 2021 CONFIG_SYSTEMACE 2022 2023 Adding this option adds support for Xilinx SystemACE 2024 chips attached via some sort of local bus. The address 2025 of the chip must also be defined in the 2026 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2027 2028 #define CONFIG_SYSTEMACE 2029 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2030 2031 When SystemACE support is added, the "ace" device type 2032 becomes available to the fat commands, i.e. fatls. 2033 2034- TFTP Fixed UDP Port: 2035 CONFIG_TFTP_PORT 2036 2037 If this is defined, the environment variable tftpsrcp 2038 is used to supply the TFTP UDP source port value. 2039 If tftpsrcp isn't defined, the normal pseudo-random port 2040 number generator is used. 2041 2042 Also, the environment variable tftpdstp is used to supply 2043 the TFTP UDP destination port value. If tftpdstp isn't 2044 defined, the normal port 69 is used. 2045 2046 The purpose for tftpsrcp is to allow a TFTP server to 2047 blindly start the TFTP transfer using the pre-configured 2048 target IP address and UDP port. This has the effect of 2049 "punching through" the (Windows XP) firewall, allowing 2050 the remainder of the TFTP transfer to proceed normally. 2051 A better solution is to properly configure the firewall, 2052 but sometimes that is not allowed. 2053 2054- Show boot progress: 2055 CONFIG_SHOW_BOOT_PROGRESS 2056 2057 Defining this option allows to add some board- 2058 specific code (calling a user-provided function 2059 "show_boot_progress(int)") that enables you to show 2060 the system's boot progress on some display (for 2061 example, some LED's) on your board. At the moment, 2062 the following checkpoints are implemented: 2063 2064- Standalone program support: 2065 CONFIG_STANDALONE_LOAD_ADDR 2066 2067 This option allows to define board specific values 2068 for the address where standalone program gets loaded, 2069 thus overwriting the architecutre dependent default 2070 settings. 2071 2072- Frame Buffer Address: 2073 CONFIG_FB_ADDR 2074 2075 Define CONFIG_FB_ADDR if you want to use specific address for 2076 frame buffer. 2077 Then system will reserve the frame buffer address to defined address 2078 instead of lcd_setmem (this function grab the memory for frame buffer 2079 by panel's size). 2080 2081 Please see board_init_f function. 2082 2083 If you want this config option then, 2084 please define it at your board config file 2085 2086Legacy uImage format: 2087 2088 Arg Where When 2089 1 common/cmd_bootm.c before attempting to boot an image 2090 -1 common/cmd_bootm.c Image header has bad magic number 2091 2 common/cmd_bootm.c Image header has correct magic number 2092 -2 common/cmd_bootm.c Image header has bad checksum 2093 3 common/cmd_bootm.c Image header has correct checksum 2094 -3 common/cmd_bootm.c Image data has bad checksum 2095 4 common/cmd_bootm.c Image data has correct checksum 2096 -4 common/cmd_bootm.c Image is for unsupported architecture 2097 5 common/cmd_bootm.c Architecture check OK 2098 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2099 6 common/cmd_bootm.c Image Type check OK 2100 -6 common/cmd_bootm.c gunzip uncompression error 2101 -7 common/cmd_bootm.c Unimplemented compression type 2102 7 common/cmd_bootm.c Uncompression OK 2103 8 common/cmd_bootm.c No uncompress/copy overwrite error 2104 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2105 2106 9 common/image.c Start initial ramdisk verification 2107 -10 common/image.c Ramdisk header has bad magic number 2108 -11 common/image.c Ramdisk header has bad checksum 2109 10 common/image.c Ramdisk header is OK 2110 -12 common/image.c Ramdisk data has bad checksum 2111 11 common/image.c Ramdisk data has correct checksum 2112 12 common/image.c Ramdisk verification complete, start loading 2113 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2114 13 common/image.c Start multifile image verification 2115 14 common/image.c No initial ramdisk, no multifile, continue. 2116 2117 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2118 2119 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2120 -31 post/post.c POST test failed, detected by post_output_backlog() 2121 -32 post/post.c POST test failed, detected by post_run_single() 2122 2123 34 common/cmd_doc.c before loading a Image from a DOC device 2124 -35 common/cmd_doc.c Bad usage of "doc" command 2125 35 common/cmd_doc.c correct usage of "doc" command 2126 -36 common/cmd_doc.c No boot device 2127 36 common/cmd_doc.c correct boot device 2128 -37 common/cmd_doc.c Unknown Chip ID on boot device 2129 37 common/cmd_doc.c correct chip ID found, device available 2130 -38 common/cmd_doc.c Read Error on boot device 2131 38 common/cmd_doc.c reading Image header from DOC device OK 2132 -39 common/cmd_doc.c Image header has bad magic number 2133 39 common/cmd_doc.c Image header has correct magic number 2134 -40 common/cmd_doc.c Error reading Image from DOC device 2135 40 common/cmd_doc.c Image header has correct magic number 2136 41 common/cmd_ide.c before loading a Image from a IDE device 2137 -42 common/cmd_ide.c Bad usage of "ide" command 2138 42 common/cmd_ide.c correct usage of "ide" command 2139 -43 common/cmd_ide.c No boot device 2140 43 common/cmd_ide.c boot device found 2141 -44 common/cmd_ide.c Device not available 2142 44 common/cmd_ide.c Device available 2143 -45 common/cmd_ide.c wrong partition selected 2144 45 common/cmd_ide.c partition selected 2145 -46 common/cmd_ide.c Unknown partition table 2146 46 common/cmd_ide.c valid partition table found 2147 -47 common/cmd_ide.c Invalid partition type 2148 47 common/cmd_ide.c correct partition type 2149 -48 common/cmd_ide.c Error reading Image Header on boot device 2150 48 common/cmd_ide.c reading Image Header from IDE device OK 2151 -49 common/cmd_ide.c Image header has bad magic number 2152 49 common/cmd_ide.c Image header has correct magic number 2153 -50 common/cmd_ide.c Image header has bad checksum 2154 50 common/cmd_ide.c Image header has correct checksum 2155 -51 common/cmd_ide.c Error reading Image from IDE device 2156 51 common/cmd_ide.c reading Image from IDE device OK 2157 52 common/cmd_nand.c before loading a Image from a NAND device 2158 -53 common/cmd_nand.c Bad usage of "nand" command 2159 53 common/cmd_nand.c correct usage of "nand" command 2160 -54 common/cmd_nand.c No boot device 2161 54 common/cmd_nand.c boot device found 2162 -55 common/cmd_nand.c Unknown Chip ID on boot device 2163 55 common/cmd_nand.c correct chip ID found, device available 2164 -56 common/cmd_nand.c Error reading Image Header on boot device 2165 56 common/cmd_nand.c reading Image Header from NAND device OK 2166 -57 common/cmd_nand.c Image header has bad magic number 2167 57 common/cmd_nand.c Image header has correct magic number 2168 -58 common/cmd_nand.c Error reading Image from NAND device 2169 58 common/cmd_nand.c reading Image from NAND device OK 2170 2171 -60 common/env_common.c Environment has a bad CRC, using default 2172 2173 64 net/eth.c starting with Ethernet configuration. 2174 -64 net/eth.c no Ethernet found. 2175 65 net/eth.c Ethernet found. 2176 2177 -80 common/cmd_net.c usage wrong 2178 80 common/cmd_net.c before calling NetLoop() 2179 -81 common/cmd_net.c some error in NetLoop() occurred 2180 81 common/cmd_net.c NetLoop() back without error 2181 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2182 82 common/cmd_net.c trying automatic boot 2183 83 common/cmd_net.c running "source" command 2184 -83 common/cmd_net.c some error in automatic boot or "source" command 2185 84 common/cmd_net.c end without errors 2186 2187FIT uImage format: 2188 2189 Arg Where When 2190 100 common/cmd_bootm.c Kernel FIT Image has correct format 2191 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2192 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2193 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2194 102 common/cmd_bootm.c Kernel unit name specified 2195 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2196 103 common/cmd_bootm.c Found configuration node 2197 104 common/cmd_bootm.c Got kernel subimage node offset 2198 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2199 105 common/cmd_bootm.c Kernel subimage hash verification OK 2200 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2201 106 common/cmd_bootm.c Architecture check OK 2202 -106 common/cmd_bootm.c Kernel subimage has wrong type 2203 107 common/cmd_bootm.c Kernel subimage type OK 2204 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2205 108 common/cmd_bootm.c Got kernel subimage data/size 2206 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2207 -109 common/cmd_bootm.c Can't get kernel subimage type 2208 -110 common/cmd_bootm.c Can't get kernel subimage comp 2209 -111 common/cmd_bootm.c Can't get kernel subimage os 2210 -112 common/cmd_bootm.c Can't get kernel subimage load address 2211 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2212 2213 120 common/image.c Start initial ramdisk verification 2214 -120 common/image.c Ramdisk FIT image has incorrect format 2215 121 common/image.c Ramdisk FIT image has correct format 2216 122 common/image.c No ramdisk subimage unit name, using configuration 2217 -122 common/image.c Can't get configuration for ramdisk subimage 2218 123 common/image.c Ramdisk unit name specified 2219 -124 common/image.c Can't get ramdisk subimage node offset 2220 125 common/image.c Got ramdisk subimage node offset 2221 -125 common/image.c Ramdisk subimage hash verification failed 2222 126 common/image.c Ramdisk subimage hash verification OK 2223 -126 common/image.c Ramdisk subimage for unsupported architecture 2224 127 common/image.c Architecture check OK 2225 -127 common/image.c Can't get ramdisk subimage data/size 2226 128 common/image.c Got ramdisk subimage data/size 2227 129 common/image.c Can't get ramdisk load address 2228 -129 common/image.c Got ramdisk load address 2229 2230 -130 common/cmd_doc.c Incorrect FIT image format 2231 131 common/cmd_doc.c FIT image format OK 2232 2233 -140 common/cmd_ide.c Incorrect FIT image format 2234 141 common/cmd_ide.c FIT image format OK 2235 2236 -150 common/cmd_nand.c Incorrect FIT image format 2237 151 common/cmd_nand.c FIT image format OK 2238 2239- Automatic software updates via TFTP server 2240 CONFIG_UPDATE_TFTP 2241 CONFIG_UPDATE_TFTP_CNT_MAX 2242 CONFIG_UPDATE_TFTP_MSEC_MAX 2243 2244 These options enable and control the auto-update feature; 2245 for a more detailed description refer to doc/README.update. 2246 2247- MTD Support (mtdparts command, UBI support) 2248 CONFIG_MTD_DEVICE 2249 2250 Adds the MTD device infrastructure from the Linux kernel. 2251 Needed for mtdparts command support. 2252 2253 CONFIG_MTD_PARTITIONS 2254 2255 Adds the MTD partitioning infrastructure from the Linux 2256 kernel. Needed for UBI support. 2257 2258- SPL framework 2259 CONFIG_SPL 2260 Enable building of SPL globally. 2261 2262 CONFIG_SPL_TEXT_BASE 2263 TEXT_BASE for linking the SPL binary. 2264 2265 CONFIG_SPL_LDSCRIPT 2266 LDSCRIPT for linking the SPL binary. 2267 2268 CONFIG_SPL_LIBCOMMON_SUPPORT 2269 Support for common/libcommon.o in SPL binary 2270 2271 CONFIG_SPL_LIBDISK_SUPPORT 2272 Support for disk/libdisk.o in SPL binary 2273 2274 CONFIG_SPL_I2C_SUPPORT 2275 Support for drivers/i2c/libi2c.o in SPL binary 2276 2277 CONFIG_SPL_GPIO_SUPPORT 2278 Support for drivers/gpio/libgpio.o in SPL binary 2279 2280 CONFIG_SPL_MMC_SUPPORT 2281 Support for drivers/mmc/libmmc.o in SPL binary 2282 2283 CONFIG_SPL_SERIAL_SUPPORT 2284 Support for drivers/serial/libserial.o in SPL binary 2285 2286 CONFIG_SPL_SPI_FLASH_SUPPORT 2287 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 2288 2289 CONFIG_SPL_SPI_SUPPORT 2290 Support for drivers/spi/libspi.o in SPL binary 2291 2292 CONFIG_SPL_FAT_SUPPORT 2293 Support for fs/fat/libfat.o in SPL binary 2294 2295 CONFIG_SPL_LIBGENERIC_SUPPORT 2296 Support for lib/libgeneric.o in SPL binary 2297 2298Modem Support: 2299-------------- 2300 2301[so far only for SMDK2400 boards] 2302 2303- Modem support enable: 2304 CONFIG_MODEM_SUPPORT 2305 2306- RTS/CTS Flow control enable: 2307 CONFIG_HWFLOW 2308 2309- Modem debug support: 2310 CONFIG_MODEM_SUPPORT_DEBUG 2311 2312 Enables debugging stuff (char screen[1024], dbg()) 2313 for modem support. Useful only with BDI2000. 2314 2315- Interrupt support (PPC): 2316 2317 There are common interrupt_init() and timer_interrupt() 2318 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 2319 for CPU specific initialization. interrupt_init_cpu() 2320 should set decrementer_count to appropriate value. If 2321 CPU resets decrementer automatically after interrupt 2322 (ppc4xx) it should set decrementer_count to zero. 2323 timer_interrupt() calls timer_interrupt_cpu() for CPU 2324 specific handling. If board has watchdog / status_led 2325 / other_activity_monitor it works automatically from 2326 general timer_interrupt(). 2327 2328- General: 2329 2330 In the target system modem support is enabled when a 2331 specific key (key combination) is pressed during 2332 power-on. Otherwise U-Boot will boot normally 2333 (autoboot). The key_pressed() function is called from 2334 board_init(). Currently key_pressed() is a dummy 2335 function, returning 1 and thus enabling modem 2336 initialization. 2337 2338 If there are no modem init strings in the 2339 environment, U-Boot proceed to autoboot; the 2340 previous output (banner, info printfs) will be 2341 suppressed, though. 2342 2343 See also: doc/README.Modem 2344 2345 2346Configuration Settings: 2347----------------------- 2348 2349- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 2350 undefine this when you're short of memory. 2351 2352- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 2353 width of the commands listed in the 'help' command output. 2354 2355- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 2356 prompt for user input. 2357 2358- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 2359 2360- CONFIG_SYS_PBSIZE: Buffer size for Console output 2361 2362- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 2363 2364- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 2365 the application (usually a Linux kernel) when it is 2366 booted 2367 2368- CONFIG_SYS_BAUDRATE_TABLE: 2369 List of legal baudrate settings for this board. 2370 2371- CONFIG_SYS_CONSOLE_INFO_QUIET 2372 Suppress display of console information at boot. 2373 2374- CONFIG_SYS_CONSOLE_IS_IN_ENV 2375 If the board specific function 2376 extern int overwrite_console (void); 2377 returns 1, the stdin, stderr and stdout are switched to the 2378 serial port, else the settings in the environment are used. 2379 2380- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 2381 Enable the call to overwrite_console(). 2382 2383- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 2384 Enable overwrite of previous console environment settings. 2385 2386- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 2387 Begin and End addresses of the area used by the 2388 simple memory test. 2389 2390- CONFIG_SYS_ALT_MEMTEST: 2391 Enable an alternate, more extensive memory test. 2392 2393- CONFIG_SYS_MEMTEST_SCRATCH: 2394 Scratch address used by the alternate memory test 2395 You only need to set this if address zero isn't writeable 2396 2397- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 2398 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 2399 this specified memory area will get subtracted from the top 2400 (end) of RAM and won't get "touched" at all by U-Boot. By 2401 fixing up gd->ram_size the Linux kernel should gets passed 2402 the now "corrected" memory size and won't touch it either. 2403 This should work for arch/ppc and arch/powerpc. Only Linux 2404 board ports in arch/powerpc with bootwrapper support that 2405 recalculate the memory size from the SDRAM controller setup 2406 will have to get fixed in Linux additionally. 2407 2408 This option can be used as a workaround for the 440EPx/GRx 2409 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 2410 be touched. 2411 2412 WARNING: Please make sure that this value is a multiple of 2413 the Linux page size (normally 4k). If this is not the case, 2414 then the end address of the Linux memory will be located at a 2415 non page size aligned address and this could cause major 2416 problems. 2417 2418- CONFIG_SYS_TFTP_LOADADDR: 2419 Default load address for network file downloads 2420 2421- CONFIG_SYS_LOADS_BAUD_CHANGE: 2422 Enable temporary baudrate change while serial download 2423 2424- CONFIG_SYS_SDRAM_BASE: 2425 Physical start address of SDRAM. _Must_ be 0 here. 2426 2427- CONFIG_SYS_MBIO_BASE: 2428 Physical start address of Motherboard I/O (if using a 2429 Cogent motherboard) 2430 2431- CONFIG_SYS_FLASH_BASE: 2432 Physical start address of Flash memory. 2433 2434- CONFIG_SYS_MONITOR_BASE: 2435 Physical start address of boot monitor code (set by 2436 make config files to be same as the text base address 2437 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 2438 CONFIG_SYS_FLASH_BASE when booting from flash. 2439 2440- CONFIG_SYS_MONITOR_LEN: 2441 Size of memory reserved for monitor code, used to 2442 determine _at_compile_time_ (!) if the environment is 2443 embedded within the U-Boot image, or in a separate 2444 flash sector. 2445 2446- CONFIG_SYS_MALLOC_LEN: 2447 Size of DRAM reserved for malloc() use. 2448 2449- CONFIG_SYS_BOOTM_LEN: 2450 Normally compressed uImages are limited to an 2451 uncompressed size of 8 MBytes. If this is not enough, 2452 you can define CONFIG_SYS_BOOTM_LEN in your board config file 2453 to adjust this setting to your needs. 2454 2455- CONFIG_SYS_BOOTMAPSZ: 2456 Maximum size of memory mapped by the startup code of 2457 the Linux kernel; all data that must be processed by 2458 the Linux kernel (bd_info, boot arguments, FDT blob if 2459 used) must be put below this limit, unless "bootm_low" 2460 enviroment variable is defined and non-zero. In such case 2461 all data for the Linux kernel must be between "bootm_low" 2462 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 2463 variable "bootm_mapsize" will override the value of 2464 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 2465 then the value in "bootm_size" will be used instead. 2466 2467- CONFIG_SYS_BOOT_RAMDISK_HIGH: 2468 Enable initrd_high functionality. If defined then the 2469 initrd_high feature is enabled and the bootm ramdisk subcommand 2470 is enabled. 2471 2472- CONFIG_SYS_BOOT_GET_CMDLINE: 2473 Enables allocating and saving kernel cmdline in space between 2474 "bootm_low" and "bootm_low" + BOOTMAPSZ. 2475 2476- CONFIG_SYS_BOOT_GET_KBD: 2477 Enables allocating and saving a kernel copy of the bd_info in 2478 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 2479 2480- CONFIG_SYS_MAX_FLASH_BANKS: 2481 Max number of Flash memory banks 2482 2483- CONFIG_SYS_MAX_FLASH_SECT: 2484 Max number of sectors on a Flash chip 2485 2486- CONFIG_SYS_FLASH_ERASE_TOUT: 2487 Timeout for Flash erase operations (in ms) 2488 2489- CONFIG_SYS_FLASH_WRITE_TOUT: 2490 Timeout for Flash write operations (in ms) 2491 2492- CONFIG_SYS_FLASH_LOCK_TOUT 2493 Timeout for Flash set sector lock bit operation (in ms) 2494 2495- CONFIG_SYS_FLASH_UNLOCK_TOUT 2496 Timeout for Flash clear lock bits operation (in ms) 2497 2498- CONFIG_SYS_FLASH_PROTECTION 2499 If defined, hardware flash sectors protection is used 2500 instead of U-Boot software protection. 2501 2502- CONFIG_SYS_DIRECT_FLASH_TFTP: 2503 2504 Enable TFTP transfers directly to flash memory; 2505 without this option such a download has to be 2506 performed in two steps: (1) download to RAM, and (2) 2507 copy from RAM to flash. 2508 2509 The two-step approach is usually more reliable, since 2510 you can check if the download worked before you erase 2511 the flash, but in some situations (when system RAM is 2512 too limited to allow for a temporary copy of the 2513 downloaded image) this option may be very useful. 2514 2515- CONFIG_SYS_FLASH_CFI: 2516 Define if the flash driver uses extra elements in the 2517 common flash structure for storing flash geometry. 2518 2519- CONFIG_FLASH_CFI_DRIVER 2520 This option also enables the building of the cfi_flash driver 2521 in the drivers directory 2522 2523- CONFIG_FLASH_CFI_MTD 2524 This option enables the building of the cfi_mtd driver 2525 in the drivers directory. The driver exports CFI flash 2526 to the MTD layer. 2527 2528- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 2529 Use buffered writes to flash. 2530 2531- CONFIG_FLASH_SPANSION_S29WS_N 2532 s29ws-n MirrorBit flash has non-standard addresses for buffered 2533 write commands. 2534 2535- CONFIG_SYS_FLASH_QUIET_TEST 2536 If this option is defined, the common CFI flash doesn't 2537 print it's warning upon not recognized FLASH banks. This 2538 is useful, if some of the configured banks are only 2539 optionally available. 2540 2541- CONFIG_FLASH_SHOW_PROGRESS 2542 If defined (must be an integer), print out countdown 2543 digits and dots. Recommended value: 45 (9..1) for 80 2544 column displays, 15 (3..1) for 40 column displays. 2545 2546- CONFIG_SYS_RX_ETH_BUFFER: 2547 Defines the number of Ethernet receive buffers. On some 2548 Ethernet controllers it is recommended to set this value 2549 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2550 buffers can be full shortly after enabling the interface 2551 on high Ethernet traffic. 2552 Defaults to 4 if not defined. 2553 2554- CONFIG_ENV_MAX_ENTRIES 2555 2556 Maximum number of entries in the hash table that is used 2557 internally to store the environment settings. The default 2558 setting is supposed to be generous and should work in most 2559 cases. This setting can be used to tune behaviour; see 2560 lib/hashtable.c for details. 2561 2562The following definitions that deal with the placement and management 2563of environment data (variable area); in general, we support the 2564following configurations: 2565 2566- CONFIG_ENV_IS_IN_FLASH: 2567 2568 Define this if the environment is in flash memory. 2569 2570 a) The environment occupies one whole flash sector, which is 2571 "embedded" in the text segment with the U-Boot code. This 2572 happens usually with "bottom boot sector" or "top boot 2573 sector" type flash chips, which have several smaller 2574 sectors at the start or the end. For instance, such a 2575 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2576 such a case you would place the environment in one of the 2577 4 kB sectors - with U-Boot code before and after it. With 2578 "top boot sector" type flash chips, you would put the 2579 environment in one of the last sectors, leaving a gap 2580 between U-Boot and the environment. 2581 2582 - CONFIG_ENV_OFFSET: 2583 2584 Offset of environment data (variable area) to the 2585 beginning of flash memory; for instance, with bottom boot 2586 type flash chips the second sector can be used: the offset 2587 for this sector is given here. 2588 2589 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 2590 2591 - CONFIG_ENV_ADDR: 2592 2593 This is just another way to specify the start address of 2594 the flash sector containing the environment (instead of 2595 CONFIG_ENV_OFFSET). 2596 2597 - CONFIG_ENV_SECT_SIZE: 2598 2599 Size of the sector containing the environment. 2600 2601 2602 b) Sometimes flash chips have few, equal sized, BIG sectors. 2603 In such a case you don't want to spend a whole sector for 2604 the environment. 2605 2606 - CONFIG_ENV_SIZE: 2607 2608 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 2609 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 2610 of this flash sector for the environment. This saves 2611 memory for the RAM copy of the environment. 2612 2613 It may also save flash memory if you decide to use this 2614 when your environment is "embedded" within U-Boot code, 2615 since then the remainder of the flash sector could be used 2616 for U-Boot code. It should be pointed out that this is 2617 STRONGLY DISCOURAGED from a robustness point of view: 2618 updating the environment in flash makes it always 2619 necessary to erase the WHOLE sector. If something goes 2620 wrong before the contents has been restored from a copy in 2621 RAM, your target system will be dead. 2622 2623 - CONFIG_ENV_ADDR_REDUND 2624 CONFIG_ENV_SIZE_REDUND 2625 2626 These settings describe a second storage area used to hold 2627 a redundant copy of the environment data, so that there is 2628 a valid backup copy in case there is a power failure during 2629 a "saveenv" operation. 2630 2631BE CAREFUL! Any changes to the flash layout, and some changes to the 2632source code will make it necessary to adapt <board>/u-boot.lds* 2633accordingly! 2634 2635 2636- CONFIG_ENV_IS_IN_NVRAM: 2637 2638 Define this if you have some non-volatile memory device 2639 (NVRAM, battery buffered SRAM) which you want to use for the 2640 environment. 2641 2642 - CONFIG_ENV_ADDR: 2643 - CONFIG_ENV_SIZE: 2644 2645 These two #defines are used to determine the memory area you 2646 want to use for environment. It is assumed that this memory 2647 can just be read and written to, without any special 2648 provision. 2649 2650BE CAREFUL! The first access to the environment happens quite early 2651in U-Boot initalization (when we try to get the setting of for the 2652console baudrate). You *MUST* have mapped your NVRAM area then, or 2653U-Boot will hang. 2654 2655Please note that even with NVRAM we still use a copy of the 2656environment in RAM: we could work on NVRAM directly, but we want to 2657keep settings there always unmodified except somebody uses "saveenv" 2658to save the current settings. 2659 2660 2661- CONFIG_ENV_IS_IN_EEPROM: 2662 2663 Use this if you have an EEPROM or similar serial access 2664 device and a driver for it. 2665 2666 - CONFIG_ENV_OFFSET: 2667 - CONFIG_ENV_SIZE: 2668 2669 These two #defines specify the offset and size of the 2670 environment area within the total memory of your EEPROM. 2671 2672 - CONFIG_SYS_I2C_EEPROM_ADDR: 2673 If defined, specified the chip address of the EEPROM device. 2674 The default address is zero. 2675 2676 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 2677 If defined, the number of bits used to address bytes in a 2678 single page in the EEPROM device. A 64 byte page, for example 2679 would require six bits. 2680 2681 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 2682 If defined, the number of milliseconds to delay between 2683 page writes. The default is zero milliseconds. 2684 2685 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 2686 The length in bytes of the EEPROM memory array address. Note 2687 that this is NOT the chip address length! 2688 2689 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 2690 EEPROM chips that implement "address overflow" are ones 2691 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2692 address and the extra bits end up in the "chip address" bit 2693 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2694 byte chips. 2695 2696 Note that we consider the length of the address field to 2697 still be one byte because the extra address bits are hidden 2698 in the chip address. 2699 2700 - CONFIG_SYS_EEPROM_SIZE: 2701 The size in bytes of the EEPROM device. 2702 2703 - CONFIG_ENV_EEPROM_IS_ON_I2C 2704 define this, if you have I2C and SPI activated, and your 2705 EEPROM, which holds the environment, is on the I2C bus. 2706 2707 - CONFIG_I2C_ENV_EEPROM_BUS 2708 if you have an Environment on an EEPROM reached over 2709 I2C muxes, you can define here, how to reach this 2710 EEPROM. For example: 2711 2712 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0" 2713 2714 EEPROM which holds the environment, is reached over 2715 a pca9547 i2c mux with address 0x70, channel 3. 2716 2717- CONFIG_ENV_IS_IN_DATAFLASH: 2718 2719 Define this if you have a DataFlash memory device which you 2720 want to use for the environment. 2721 2722 - CONFIG_ENV_OFFSET: 2723 - CONFIG_ENV_ADDR: 2724 - CONFIG_ENV_SIZE: 2725 2726 These three #defines specify the offset and size of the 2727 environment area within the total memory of your DataFlash placed 2728 at the specified address. 2729 2730- CONFIG_ENV_IS_IN_NAND: 2731 2732 Define this if you have a NAND device which you want to use 2733 for the environment. 2734 2735 - CONFIG_ENV_OFFSET: 2736 - CONFIG_ENV_SIZE: 2737 2738 These two #defines specify the offset and size of the environment 2739 area within the first NAND device. CONFIG_ENV_OFFSET must be 2740 aligned to an erase block boundary. 2741 2742 - CONFIG_ENV_OFFSET_REDUND (optional): 2743 2744 This setting describes a second storage area of CONFIG_ENV_SIZE 2745 size used to hold a redundant copy of the environment data, so 2746 that there is a valid backup copy in case there is a power failure 2747 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 2748 aligned to an erase block boundary. 2749 2750 - CONFIG_ENV_RANGE (optional): 2751 2752 Specifies the length of the region in which the environment 2753 can be written. This should be a multiple of the NAND device's 2754 block size. Specifying a range with more erase blocks than 2755 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 2756 the range to be avoided. 2757 2758 - CONFIG_ENV_OFFSET_OOB (optional): 2759 2760 Enables support for dynamically retrieving the offset of the 2761 environment from block zero's out-of-band data. The 2762 "nand env.oob" command can be used to record this offset. 2763 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 2764 using CONFIG_ENV_OFFSET_OOB. 2765 2766- CONFIG_NAND_ENV_DST 2767 2768 Defines address in RAM to which the nand_spl code should copy the 2769 environment. If redundant environment is used, it will be copied to 2770 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 2771 2772- CONFIG_SYS_SPI_INIT_OFFSET 2773 2774 Defines offset to the initial SPI buffer area in DPRAM. The 2775 area is used at an early stage (ROM part) if the environment 2776 is configured to reside in the SPI EEPROM: We need a 520 byte 2777 scratch DPRAM area. It is used between the two initialization 2778 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2779 to be a good choice since it makes it far enough from the 2780 start of the data area as well as from the stack pointer. 2781 2782Please note that the environment is read-only until the monitor 2783has been relocated to RAM and a RAM copy of the environment has been 2784created; also, when using EEPROM you will have to use getenv_f() 2785until then to read environment variables. 2786 2787The environment is protected by a CRC32 checksum. Before the monitor 2788is relocated into RAM, as a result of a bad CRC you will be working 2789with the compiled-in default environment - *silently*!!! [This is 2790necessary, because the first environment variable we need is the 2791"baudrate" setting for the console - if we have a bad CRC, we don't 2792have any device yet where we could complain.] 2793 2794Note: once the monitor has been relocated, then it will complain if 2795the default environment is used; a new CRC is computed as soon as you 2796use the "saveenv" command to store a valid environment. 2797 2798- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 2799 Echo the inverted Ethernet link state to the fault LED. 2800 2801 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 2802 also needs to be defined. 2803 2804- CONFIG_SYS_FAULT_MII_ADDR: 2805 MII address of the PHY to check for the Ethernet link state. 2806 2807- CONFIG_NS16550_MIN_FUNCTIONS: 2808 Define this if you desire to only have use of the NS16550_init 2809 and NS16550_putc functions for the serial driver located at 2810 drivers/serial/ns16550.c. This option is useful for saving 2811 space for already greatly restricted images, including but not 2812 limited to NAND_SPL configurations. 2813 2814Low Level (hardware related) configuration options: 2815--------------------------------------------------- 2816 2817- CONFIG_SYS_CACHELINE_SIZE: 2818 Cache Line Size of the CPU. 2819 2820- CONFIG_SYS_DEFAULT_IMMR: 2821 Default address of the IMMR after system reset. 2822 2823 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2824 and RPXsuper) to be able to adjust the position of 2825 the IMMR register after a reset. 2826 2827- Floppy Disk Support: 2828 CONFIG_SYS_FDC_DRIVE_NUMBER 2829 2830 the default drive number (default value 0) 2831 2832 CONFIG_SYS_ISA_IO_STRIDE 2833 2834 defines the spacing between FDC chipset registers 2835 (default value 1) 2836 2837 CONFIG_SYS_ISA_IO_OFFSET 2838 2839 defines the offset of register from address. It 2840 depends on which part of the data bus is connected to 2841 the FDC chipset. (default value 0) 2842 2843 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 2844 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 2845 default value. 2846 2847 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 2848 fdc_hw_init() is called at the beginning of the FDC 2849 setup. fdc_hw_init() must be provided by the board 2850 source code. It is used to make hardware dependant 2851 initializations. 2852 2853- CONFIG_IDE_AHB: 2854 Most IDE controllers were designed to be connected with PCI 2855 interface. Only few of them were designed for AHB interface. 2856 When software is doing ATA command and data transfer to 2857 IDE devices through IDE-AHB controller, some additional 2858 registers accessing to these kind of IDE-AHB controller 2859 is requierd. 2860 2861- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 2862 DO NOT CHANGE unless you know exactly what you're 2863 doing! (11-4) [MPC8xx/82xx systems only] 2864 2865- CONFIG_SYS_INIT_RAM_ADDR: 2866 2867 Start address of memory area that can be used for 2868 initial data and stack; please note that this must be 2869 writable memory that is working WITHOUT special 2870 initialization, i. e. you CANNOT use normal RAM which 2871 will become available only after programming the 2872 memory controller and running certain initialization 2873 sequences. 2874 2875 U-Boot uses the following memory types: 2876 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2877 - MPC824X: data cache 2878 - PPC4xx: data cache 2879 2880- CONFIG_SYS_GBL_DATA_OFFSET: 2881 2882 Offset of the initial data structure in the memory 2883 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 2884 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 2885 data is located at the end of the available space 2886 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 2887 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 2888 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 2889 CONFIG_SYS_GBL_DATA_OFFSET) downward. 2890 2891 Note: 2892 On the MPC824X (or other systems that use the data 2893 cache for initial memory) the address chosen for 2894 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 2895 point to an otherwise UNUSED address space between 2896 the top of RAM and the start of the PCI space. 2897 2898- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 2899 2900- CONFIG_SYS_SYPCR: System Protection Control (11-9) 2901 2902- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 2903 2904- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 2905 2906- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 2907 2908- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 2909 2910- CONFIG_SYS_OR_TIMING_SDRAM: 2911 SDRAM timing 2912 2913- CONFIG_SYS_MAMR_PTA: 2914 periodic timer for refresh 2915 2916- CONFIG_SYS_DER: Debug Event Register (37-47) 2917 2918- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 2919 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 2920 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 2921 CONFIG_SYS_BR1_PRELIM: 2922 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 2923 2924- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 2925 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 2926 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 2927 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 2928 2929- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 2930 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 2931 Machine Mode Register and Memory Periodic Timer 2932 Prescaler definitions (SDRAM timing) 2933 2934- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 2935 enable I2C microcode relocation patch (MPC8xx); 2936 define relocation offset in DPRAM [DSP2] 2937 2938- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 2939 enable SMC microcode relocation patch (MPC8xx); 2940 define relocation offset in DPRAM [SMC1] 2941 2942- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 2943 enable SPI microcode relocation patch (MPC8xx); 2944 define relocation offset in DPRAM [SCC4] 2945 2946- CONFIG_SYS_USE_OSCCLK: 2947 Use OSCM clock mode on MBX8xx board. Be careful, 2948 wrong setting might damage your board. Read 2949 doc/README.MBX before setting this variable! 2950 2951- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 2952 Offset of the bootmode word in DPRAM used by post 2953 (Power On Self Tests). This definition overrides 2954 #define'd default value in commproc.h resp. 2955 cpm_8260.h. 2956 2957- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 2958 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 2959 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 2960 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 2961 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 2962 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 2963 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 2964 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 2965 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 2966 2967- CONFIG_PCI_DISABLE_PCIE: 2968 Disable PCI-Express on systems where it is supported but not 2969 required. 2970 2971- CONFIG_SYS_SRIO: 2972 Chip has SRIO or not 2973 2974- CONFIG_SRIO1: 2975 Board has SRIO 1 port available 2976 2977- CONFIG_SRIO2: 2978 Board has SRIO 2 port available 2979 2980- CONFIG_SYS_SRIOn_MEM_VIRT: 2981 Virtual Address of SRIO port 'n' memory region 2982 2983- CONFIG_SYS_SRIOn_MEM_PHYS: 2984 Physical Address of SRIO port 'n' memory region 2985 2986- CONFIG_SYS_SRIOn_MEM_SIZE: 2987 Size of SRIO port 'n' memory region 2988 2989- CONFIG_SYS_NDFC_16 2990 Defined to tell the NDFC that the NAND chip is using a 2991 16 bit bus. 2992 2993- CONFIG_SYS_NDFC_EBC0_CFG 2994 Sets the EBC0_CFG register for the NDFC. If not defined 2995 a default value will be used. 2996 2997- CONFIG_SPD_EEPROM 2998 Get DDR timing information from an I2C EEPROM. Common 2999 with pluggable memory modules such as SODIMMs 3000 3001 SPD_EEPROM_ADDRESS 3002 I2C address of the SPD EEPROM 3003 3004- CONFIG_SYS_SPD_BUS_NUM 3005 If SPD EEPROM is on an I2C bus other than the first 3006 one, specify here. Note that the value must resolve 3007 to something your driver can deal with. 3008 3009- CONFIG_SYS_DDR_RAW_TIMING 3010 Get DDR timing information from other than SPD. Common with 3011 soldered DDR chips onboard without SPD. DDR raw timing 3012 parameters are extracted from datasheet and hard-coded into 3013 header files or board specific files. 3014 3015- CONFIG_SYS_83XX_DDR_USES_CS0 3016 Only for 83xx systems. If specified, then DDR should 3017 be configured using CS0 and CS1 instead of CS2 and CS3. 3018 3019- CONFIG_ETHER_ON_FEC[12] 3020 Define to enable FEC[12] on a 8xx series processor. 3021 3022- CONFIG_FEC[12]_PHY 3023 Define to the hardcoded PHY address which corresponds 3024 to the given FEC; i. e. 3025 #define CONFIG_FEC1_PHY 4 3026 means that the PHY with address 4 is connected to FEC1 3027 3028 When set to -1, means to probe for first available. 3029 3030- CONFIG_FEC[12]_PHY_NORXERR 3031 The PHY does not have a RXERR line (RMII only). 3032 (so program the FEC to ignore it). 3033 3034- CONFIG_RMII 3035 Enable RMII mode for all FECs. 3036 Note that this is a global option, we can't 3037 have one FEC in standard MII mode and another in RMII mode. 3038 3039- CONFIG_CRC32_VERIFY 3040 Add a verify option to the crc32 command. 3041 The syntax is: 3042 3043 => crc32 -v <address> <count> <crc32> 3044 3045 Where address/count indicate a memory area 3046 and crc32 is the correct crc32 which the 3047 area should have. 3048 3049- CONFIG_LOOPW 3050 Add the "loopw" memory command. This only takes effect if 3051 the memory commands are activated globally (CONFIG_CMD_MEM). 3052 3053- CONFIG_MX_CYCLIC 3054 Add the "mdc" and "mwc" memory commands. These are cyclic 3055 "md/mw" commands. 3056 Examples: 3057 3058 => mdc.b 10 4 500 3059 This command will print 4 bytes (10,11,12,13) each 500 ms. 3060 3061 => mwc.l 100 12345678 10 3062 This command will write 12345678 to address 100 all 10 ms. 3063 3064 This only takes effect if the memory commands are activated 3065 globally (CONFIG_CMD_MEM). 3066 3067- CONFIG_SKIP_LOWLEVEL_INIT 3068 [ARM only] If this variable is defined, then certain 3069 low level initializations (like setting up the memory 3070 controller) are omitted and/or U-Boot does not 3071 relocate itself into RAM. 3072 3073 Normally this variable MUST NOT be defined. The only 3074 exception is when U-Boot is loaded (to RAM) by some 3075 other boot loader or by a debugger which performs 3076 these initializations itself. 3077 3078- CONFIG_SPL_BUILD 3079 Modifies the behaviour of start.S when compiling a loader 3080 that is executed before the actual U-Boot. E.g. when 3081 compiling a NAND SPL. 3082 3083- CONFIG_USE_ARCH_MEMCPY 3084 CONFIG_USE_ARCH_MEMSET 3085 If these options are used a optimized version of memcpy/memset will 3086 be used if available. These functions may be faster under some 3087 conditions but may increase the binary size. 3088 3089Building the Software: 3090====================== 3091 3092Building U-Boot has been tested in several native build environments 3093and in many different cross environments. Of course we cannot support 3094all possibly existing versions of cross development tools in all 3095(potentially obsolete) versions. In case of tool chain problems we 3096recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 3097which is extensively used to build and test U-Boot. 3098 3099If you are not using a native environment, it is assumed that you 3100have GNU cross compiling tools available in your path. In this case, 3101you must set the environment variable CROSS_COMPILE in your shell. 3102Note that no changes to the Makefile or any other source files are 3103necessary. For example using the ELDK on a 4xx CPU, please enter: 3104 3105 $ CROSS_COMPILE=ppc_4xx- 3106 $ export CROSS_COMPILE 3107 3108Note: If you wish to generate Windows versions of the utilities in 3109 the tools directory you can use the MinGW toolchain 3110 (http://www.mingw.org). Set your HOST tools to the MinGW 3111 toolchain and execute 'make tools'. For example: 3112 3113 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 3114 3115 Binaries such as tools/mkimage.exe will be created which can 3116 be executed on computers running Windows. 3117 3118U-Boot is intended to be simple to build. After installing the 3119sources you must configure U-Boot for one specific board type. This 3120is done by typing: 3121 3122 make NAME_config 3123 3124where "NAME_config" is the name of one of the existing configu- 3125rations; see the main Makefile for supported names. 3126 3127Note: for some board special configuration names may exist; check if 3128 additional information is available from the board vendor; for 3129 instance, the TQM823L systems are available without (standard) 3130 or with LCD support. You can select such additional "features" 3131 when choosing the configuration, i. e. 3132 3133 make TQM823L_config 3134 - will configure for a plain TQM823L, i. e. no LCD support 3135 3136 make TQM823L_LCD_config 3137 - will configure for a TQM823L with U-Boot console on LCD 3138 3139 etc. 3140 3141 3142Finally, type "make all", and you should get some working U-Boot 3143images ready for download to / installation on your system: 3144 3145- "u-boot.bin" is a raw binary image 3146- "u-boot" is an image in ELF binary format 3147- "u-boot.srec" is in Motorola S-Record format 3148 3149By default the build is performed locally and the objects are saved 3150in the source directory. One of the two methods can be used to change 3151this behavior and build U-Boot to some external directory: 3152 31531. Add O= to the make command line invocations: 3154 3155 make O=/tmp/build distclean 3156 make O=/tmp/build NAME_config 3157 make O=/tmp/build all 3158 31592. Set environment variable BUILD_DIR to point to the desired location: 3160 3161 export BUILD_DIR=/tmp/build 3162 make distclean 3163 make NAME_config 3164 make all 3165 3166Note that the command line "O=" setting overrides the BUILD_DIR environment 3167variable. 3168 3169 3170Please be aware that the Makefiles assume you are using GNU make, so 3171for instance on NetBSD you might need to use "gmake" instead of 3172native "make". 3173 3174 3175If the system board that you have is not listed, then you will need 3176to port U-Boot to your hardware platform. To do this, follow these 3177steps: 3178 31791. Add a new configuration option for your board to the toplevel 3180 "Makefile" and to the "MAKEALL" script, using the existing 3181 entries as examples. Note that here and at many other places 3182 boards and other names are listed in alphabetical sort order. Please 3183 keep this order. 31842. Create a new directory to hold your board specific code. Add any 3185 files you need. In your board directory, you will need at least 3186 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 31873. Create a new configuration file "include/configs/<board>.h" for 3188 your board 31893. If you're porting U-Boot to a new CPU, then also create a new 3190 directory to hold your CPU specific code. Add any files you need. 31914. Run "make <board>_config" with your new name. 31925. Type "make", and you should get a working "u-boot.srec" file 3193 to be installed on your target system. 31946. Debug and solve any problems that might arise. 3195 [Of course, this last step is much harder than it sounds.] 3196 3197 3198Testing of U-Boot Modifications, Ports to New Hardware, etc.: 3199============================================================== 3200 3201If you have modified U-Boot sources (for instance added a new board 3202or support for new devices, a new CPU, etc.) you are expected to 3203provide feedback to the other developers. The feedback normally takes 3204the form of a "patch", i. e. a context diff against a certain (latest 3205official or latest in the git repository) version of U-Boot sources. 3206 3207But before you submit such a patch, please verify that your modifi- 3208cation did not break existing code. At least make sure that *ALL* of 3209the supported boards compile WITHOUT ANY compiler warnings. To do so, 3210just run the "MAKEALL" script, which will configure and build U-Boot 3211for ALL supported system. Be warned, this will take a while. You can 3212select which (cross) compiler to use by passing a `CROSS_COMPILE' 3213environment variable to the script, i. e. to use the ELDK cross tools 3214you can type 3215 3216 CROSS_COMPILE=ppc_8xx- MAKEALL 3217 3218or to build on a native PowerPC system you can type 3219 3220 CROSS_COMPILE=' ' MAKEALL 3221 3222When using the MAKEALL script, the default behaviour is to build 3223U-Boot in the source directory. This location can be changed by 3224setting the BUILD_DIR environment variable. Also, for each target 3225built, the MAKEALL script saves two log files (<target>.ERR and 3226<target>.MAKEALL) in the <source dir>/LOG directory. This default 3227location can be changed by setting the MAKEALL_LOGDIR environment 3228variable. For example: 3229 3230 export BUILD_DIR=/tmp/build 3231 export MAKEALL_LOGDIR=/tmp/log 3232 CROSS_COMPILE=ppc_8xx- MAKEALL 3233 3234With the above settings build objects are saved in the /tmp/build, 3235log files are saved in the /tmp/log and the source tree remains clean 3236during the whole build process. 3237 3238 3239See also "U-Boot Porting Guide" below. 3240 3241 3242Monitor Commands - Overview: 3243============================ 3244 3245go - start application at address 'addr' 3246run - run commands in an environment variable 3247bootm - boot application image from memory 3248bootp - boot image via network using BootP/TFTP protocol 3249tftpboot- boot image via network using TFTP protocol 3250 and env variables "ipaddr" and "serverip" 3251 (and eventually "gatewayip") 3252rarpboot- boot image via network using RARP/TFTP protocol 3253diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 3254loads - load S-Record file over serial line 3255loadb - load binary file over serial line (kermit mode) 3256md - memory display 3257mm - memory modify (auto-incrementing) 3258nm - memory modify (constant address) 3259mw - memory write (fill) 3260cp - memory copy 3261cmp - memory compare 3262crc32 - checksum calculation 3263i2c - I2C sub-system 3264sspi - SPI utility commands 3265base - print or set address offset 3266printenv- print environment variables 3267setenv - set environment variables 3268saveenv - save environment variables to persistent storage 3269protect - enable or disable FLASH write protection 3270erase - erase FLASH memory 3271flinfo - print FLASH memory information 3272bdinfo - print Board Info structure 3273iminfo - print header information for application image 3274coninfo - print console devices and informations 3275ide - IDE sub-system 3276loop - infinite loop on address range 3277loopw - infinite write loop on address range 3278mtest - simple RAM test 3279icache - enable or disable instruction cache 3280dcache - enable or disable data cache 3281reset - Perform RESET of the CPU 3282echo - echo args to console 3283version - print monitor version 3284help - print online help 3285? - alias for 'help' 3286 3287 3288Monitor Commands - Detailed Description: 3289======================================== 3290 3291TODO. 3292 3293For now: just type "help <command>". 3294 3295 3296Environment Variables: 3297====================== 3298 3299U-Boot supports user configuration using Environment Variables which 3300can be made persistent by saving to Flash memory. 3301 3302Environment Variables are set using "setenv", printed using 3303"printenv", and saved to Flash using "saveenv". Using "setenv" 3304without a value can be used to delete a variable from the 3305environment. As long as you don't save the environment you are 3306working with an in-memory copy. In case the Flash area containing the 3307environment is erased by accident, a default environment is provided. 3308 3309Some configuration options can be set using Environment Variables. 3310 3311List of environment variables (most likely not complete): 3312 3313 baudrate - see CONFIG_BAUDRATE 3314 3315 bootdelay - see CONFIG_BOOTDELAY 3316 3317 bootcmd - see CONFIG_BOOTCOMMAND 3318 3319 bootargs - Boot arguments when booting an RTOS image 3320 3321 bootfile - Name of the image to load with TFTP 3322 3323 bootm_low - Memory range available for image processing in the bootm 3324 command can be restricted. This variable is given as 3325 a hexadecimal number and defines lowest address allowed 3326 for use by the bootm command. See also "bootm_size" 3327 environment variable. Address defined by "bootm_low" is 3328 also the base of the initial memory mapping for the Linux 3329 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 3330 bootm_mapsize. 3331 3332 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 3333 This variable is given as a hexadecimal number and it 3334 defines the size of the memory region starting at base 3335 address bootm_low that is accessible by the Linux kernel 3336 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 3337 as the default value if it is defined, and bootm_size is 3338 used otherwise. 3339 3340 bootm_size - Memory range available for image processing in the bootm 3341 command can be restricted. This variable is given as 3342 a hexadecimal number and defines the size of the region 3343 allowed for use by the bootm command. See also "bootm_low" 3344 environment variable. 3345 3346 updatefile - Location of the software update file on a TFTP server, used 3347 by the automatic software update feature. Please refer to 3348 documentation in doc/README.update for more details. 3349 3350 autoload - if set to "no" (any string beginning with 'n'), 3351 "bootp" will just load perform a lookup of the 3352 configuration from the BOOTP server, but not try to 3353 load any image using TFTP 3354 3355 autostart - if set to "yes", an image loaded using the "bootp", 3356 "rarpboot", "tftpboot" or "diskboot" commands will 3357 be automatically started (by internally calling 3358 "bootm") 3359 3360 If set to "no", a standalone image passed to the 3361 "bootm" command will be copied to the load address 3362 (and eventually uncompressed), but NOT be started. 3363 This can be used to load and uncompress arbitrary 3364 data. 3365 3366 fdt_high - if set this restricts the maximum address that the 3367 flattened device tree will be copied into upon boot. 3368 If this is set to the special value 0xFFFFFFFF then 3369 the fdt will not be copied at all on boot. For this 3370 to work it must reside in writable memory, have 3371 sufficient padding on the end of it for u-boot to 3372 add the information it needs into it, and the memory 3373 must be accessible by the kernel. 3374 3375 i2cfast - (PPC405GP|PPC405EP only) 3376 if set to 'y' configures Linux I2C driver for fast 3377 mode (400kHZ). This environment variable is used in 3378 initialization code. So, for changes to be effective 3379 it must be saved and board must be reset. 3380 3381 initrd_high - restrict positioning of initrd images: 3382 If this variable is not set, initrd images will be 3383 copied to the highest possible address in RAM; this 3384 is usually what you want since it allows for 3385 maximum initrd size. If for some reason you want to 3386 make sure that the initrd image is loaded below the 3387 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 3388 variable to a value of "no" or "off" or "0". 3389 Alternatively, you can set it to a maximum upper 3390 address to use (U-Boot will still check that it 3391 does not overwrite the U-Boot stack and data). 3392 3393 For instance, when you have a system with 16 MB 3394 RAM, and want to reserve 4 MB from use by Linux, 3395 you can do this by adding "mem=12M" to the value of 3396 the "bootargs" variable. However, now you must make 3397 sure that the initrd image is placed in the first 3398 12 MB as well - this can be done with 3399 3400 setenv initrd_high 00c00000 3401 3402 If you set initrd_high to 0xFFFFFFFF, this is an 3403 indication to U-Boot that all addresses are legal 3404 for the Linux kernel, including addresses in flash 3405 memory. In this case U-Boot will NOT COPY the 3406 ramdisk at all. This may be useful to reduce the 3407 boot time on your system, but requires that this 3408 feature is supported by your Linux kernel. 3409 3410 ipaddr - IP address; needed for tftpboot command 3411 3412 loadaddr - Default load address for commands like "bootp", 3413 "rarpboot", "tftpboot", "loadb" or "diskboot" 3414 3415 loads_echo - see CONFIG_LOADS_ECHO 3416 3417 serverip - TFTP server IP address; needed for tftpboot command 3418 3419 bootretry - see CONFIG_BOOT_RETRY_TIME 3420 3421 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 3422 3423 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 3424 3425 ethprime - When CONFIG_NET_MULTI is enabled controls which 3426 interface is used first. 3427 3428 ethact - When CONFIG_NET_MULTI is enabled controls which 3429 interface is currently active. For example you 3430 can do the following 3431 3432 => setenv ethact FEC 3433 => ping 192.168.0.1 # traffic sent on FEC 3434 => setenv ethact SCC 3435 => ping 10.0.0.1 # traffic sent on SCC 3436 3437 ethrotate - When set to "no" U-Boot does not go through all 3438 available network interfaces. 3439 It just stays at the currently selected interface. 3440 3441 netretry - When set to "no" each network operation will 3442 either succeed or fail without retrying. 3443 When set to "once" the network operation will 3444 fail when all the available network interfaces 3445 are tried once without success. 3446 Useful on scripts which control the retry operation 3447 themselves. 3448 3449 npe_ucode - set load address for the NPE microcode 3450 3451 tftpsrcport - If this is set, the value is used for TFTP's 3452 UDP source port. 3453 3454 tftpdstport - If this is set, the value is used for TFTP's UDP 3455 destination port instead of the Well Know Port 69. 3456 3457 tftpblocksize - Block size to use for TFTP transfers; if not set, 3458 we use the TFTP server's default block size 3459 3460 tftptimeout - Retransmission timeout for TFTP packets (in milli- 3461 seconds, minimum value is 1000 = 1 second). Defines 3462 when a packet is considered to be lost so it has to 3463 be retransmitted. The default is 5000 = 5 seconds. 3464 Lowering this value may make downloads succeed 3465 faster in networks with high packet loss rates or 3466 with unreliable TFTP servers. 3467 3468 vlan - When set to a value < 4095 the traffic over 3469 Ethernet is encapsulated/received over 802.1q 3470 VLAN tagged frames. 3471 3472The following environment variables may be used and automatically 3473updated by the network boot commands ("bootp" and "rarpboot"), 3474depending the information provided by your boot server: 3475 3476 bootfile - see above 3477 dnsip - IP address of your Domain Name Server 3478 dnsip2 - IP address of your secondary Domain Name Server 3479 gatewayip - IP address of the Gateway (Router) to use 3480 hostname - Target hostname 3481 ipaddr - see above 3482 netmask - Subnet Mask 3483 rootpath - Pathname of the root filesystem on the NFS server 3484 serverip - see above 3485 3486 3487There are two special Environment Variables: 3488 3489 serial# - contains hardware identification information such 3490 as type string and/or serial number 3491 ethaddr - Ethernet address 3492 3493These variables can be set only once (usually during manufacturing of 3494the board). U-Boot refuses to delete or overwrite these variables 3495once they have been set once. 3496 3497 3498Further special Environment Variables: 3499 3500 ver - Contains the U-Boot version string as printed 3501 with the "version" command. This variable is 3502 readonly (see CONFIG_VERSION_VARIABLE). 3503 3504 3505Please note that changes to some configuration parameters may take 3506only effect after the next boot (yes, that's just like Windoze :-). 3507 3508 3509Command Line Parsing: 3510===================== 3511 3512There are two different command line parsers available with U-Boot: 3513the old "simple" one, and the much more powerful "hush" shell: 3514 3515Old, simple command line parser: 3516-------------------------------- 3517 3518- supports environment variables (through setenv / saveenv commands) 3519- several commands on one line, separated by ';' 3520- variable substitution using "... ${name} ..." syntax 3521- special characters ('$', ';') can be escaped by prefixing with '\', 3522 for example: 3523 setenv bootcmd bootm \${address} 3524- You can also escape text by enclosing in single apostrophes, for example: 3525 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 3526 3527Hush shell: 3528----------- 3529 3530- similar to Bourne shell, with control structures like 3531 if...then...else...fi, for...do...done; while...do...done, 3532 until...do...done, ... 3533- supports environment ("global") variables (through setenv / saveenv 3534 commands) and local shell variables (through standard shell syntax 3535 "name=value"); only environment variables can be used with "run" 3536 command 3537 3538General rules: 3539-------------- 3540 3541(1) If a command line (or an environment variable executed by a "run" 3542 command) contains several commands separated by semicolon, and 3543 one of these commands fails, then the remaining commands will be 3544 executed anyway. 3545 3546(2) If you execute several variables with one call to run (i. e. 3547 calling run with a list of variables as arguments), any failing 3548 command will cause "run" to terminate, i. e. the remaining 3549 variables are not executed. 3550 3551Note for Redundant Ethernet Interfaces: 3552======================================= 3553 3554Some boards come with redundant Ethernet interfaces; U-Boot supports 3555such configurations and is capable of automatic selection of a 3556"working" interface when needed. MAC assignment works as follows: 3557 3558Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 3559MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 3560"eth1addr" (=>eth1), "eth2addr", ... 3561 3562If the network interface stores some valid MAC address (for instance 3563in SROM), this is used as default address if there is NO correspon- 3564ding setting in the environment; if the corresponding environment 3565variable is set, this overrides the settings in the card; that means: 3566 3567o If the SROM has a valid MAC address, and there is no address in the 3568 environment, the SROM's address is used. 3569 3570o If there is no valid address in the SROM, and a definition in the 3571 environment exists, then the value from the environment variable is 3572 used. 3573 3574o If both the SROM and the environment contain a MAC address, and 3575 both addresses are the same, this MAC address is used. 3576 3577o If both the SROM and the environment contain a MAC address, and the 3578 addresses differ, the value from the environment is used and a 3579 warning is printed. 3580 3581o If neither SROM nor the environment contain a MAC address, an error 3582 is raised. 3583 3584If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 3585will be programmed into hardware as part of the initialization process. This 3586may be skipped by setting the appropriate 'ethmacskip' environment variable. 3587The naming convention is as follows: 3588"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 3589 3590Image Formats: 3591============== 3592 3593U-Boot is capable of booting (and performing other auxiliary operations on) 3594images in two formats: 3595 3596New uImage format (FIT) 3597----------------------- 3598 3599Flexible and powerful format based on Flattened Image Tree -- FIT (similar 3600to Flattened Device Tree). It allows the use of images with multiple 3601components (several kernels, ramdisks, etc.), with contents protected by 3602SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 3603 3604 3605Old uImage format 3606----------------- 3607 3608Old image format is based on binary files which can be basically anything, 3609preceded by a special header; see the definitions in include/image.h for 3610details; basically, the header defines the following image properties: 3611 3612* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 3613 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 3614 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 3615 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 3616 INTEGRITY). 3617* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 3618 IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 3619 Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC). 3620* Compression Type (uncompressed, gzip, bzip2) 3621* Load Address 3622* Entry Point 3623* Image Name 3624* Image Timestamp 3625 3626The header is marked by a special Magic Number, and both the header 3627and the data portions of the image are secured against corruption by 3628CRC32 checksums. 3629 3630 3631Linux Support: 3632============== 3633 3634Although U-Boot should support any OS or standalone application 3635easily, the main focus has always been on Linux during the design of 3636U-Boot. 3637 3638U-Boot includes many features that so far have been part of some 3639special "boot loader" code within the Linux kernel. Also, any 3640"initrd" images to be used are no longer part of one big Linux image; 3641instead, kernel and "initrd" are separate images. This implementation 3642serves several purposes: 3643 3644- the same features can be used for other OS or standalone 3645 applications (for instance: using compressed images to reduce the 3646 Flash memory footprint) 3647 3648- it becomes much easier to port new Linux kernel versions because 3649 lots of low-level, hardware dependent stuff are done by U-Boot 3650 3651- the same Linux kernel image can now be used with different "initrd" 3652 images; of course this also means that different kernel images can 3653 be run with the same "initrd". This makes testing easier (you don't 3654 have to build a new "zImage.initrd" Linux image when you just 3655 change a file in your "initrd"). Also, a field-upgrade of the 3656 software is easier now. 3657 3658 3659Linux HOWTO: 3660============ 3661 3662Porting Linux to U-Boot based systems: 3663--------------------------------------- 3664 3665U-Boot cannot save you from doing all the necessary modifications to 3666configure the Linux device drivers for use with your target hardware 3667(no, we don't intend to provide a full virtual machine interface to 3668Linux :-). 3669 3670But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 3671 3672Just make sure your machine specific header file (for instance 3673include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3674Information structure as we define in include/asm-<arch>/u-boot.h, 3675and make sure that your definition of IMAP_ADDR uses the same value 3676as your U-Boot configuration in CONFIG_SYS_IMMR. 3677 3678 3679Configuring the Linux kernel: 3680----------------------------- 3681 3682No specific requirements for U-Boot. Make sure you have some root 3683device (initial ramdisk, NFS) for your target system. 3684 3685 3686Building a Linux Image: 3687----------------------- 3688 3689With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3690not used. If you use recent kernel source, a new build target 3691"uImage" will exist which automatically builds an image usable by 3692U-Boot. Most older kernels also have support for a "pImage" target, 3693which was introduced for our predecessor project PPCBoot and uses a 3694100% compatible format. 3695 3696Example: 3697 3698 make TQM850L_config 3699 make oldconfig 3700 make dep 3701 make uImage 3702 3703The "uImage" build target uses a special tool (in 'tools/mkimage') to 3704encapsulate a compressed Linux kernel image with header information, 3705CRC32 checksum etc. for use with U-Boot. This is what we are doing: 3706 3707* build a standard "vmlinux" kernel image (in ELF binary format): 3708 3709* convert the kernel into a raw binary image: 3710 3711 ${CROSS_COMPILE}-objcopy -O binary \ 3712 -R .note -R .comment \ 3713 -S vmlinux linux.bin 3714 3715* compress the binary image: 3716 3717 gzip -9 linux.bin 3718 3719* package compressed binary image for U-Boot: 3720 3721 mkimage -A ppc -O linux -T kernel -C gzip \ 3722 -a 0 -e 0 -n "Linux Kernel Image" \ 3723 -d linux.bin.gz uImage 3724 3725 3726The "mkimage" tool can also be used to create ramdisk images for use 3727with U-Boot, either separated from the Linux kernel image, or 3728combined into one file. "mkimage" encapsulates the images with a 64 3729byte header containing information about target architecture, 3730operating system, image type, compression method, entry points, time 3731stamp, CRC32 checksums, etc. 3732 3733"mkimage" can be called in two ways: to verify existing images and 3734print the header information, or to build new images. 3735 3736In the first form (with "-l" option) mkimage lists the information 3737contained in the header of an existing U-Boot image; this includes 3738checksum verification: 3739 3740 tools/mkimage -l image 3741 -l ==> list image header information 3742 3743The second form (with "-d" option) is used to build a U-Boot image 3744from a "data file" which is used as image payload: 3745 3746 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 3747 -n name -d data_file image 3748 -A ==> set architecture to 'arch' 3749 -O ==> set operating system to 'os' 3750 -T ==> set image type to 'type' 3751 -C ==> set compression type 'comp' 3752 -a ==> set load address to 'addr' (hex) 3753 -e ==> set entry point to 'ep' (hex) 3754 -n ==> set image name to 'name' 3755 -d ==> use image data from 'datafile' 3756 3757Right now, all Linux kernels for PowerPC systems use the same load 3758address (0x00000000), but the entry point address depends on the 3759kernel version: 3760 3761- 2.2.x kernels have the entry point at 0x0000000C, 3762- 2.3.x and later kernels have the entry point at 0x00000000. 3763 3764So a typical call to build a U-Boot image would read: 3765 3766 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3767 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 3768 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 3769 > examples/uImage.TQM850L 3770 Image Name: 2.4.4 kernel for TQM850L 3771 Created: Wed Jul 19 02:34:59 2000 3772 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3773 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3774 Load Address: 0x00000000 3775 Entry Point: 0x00000000 3776 3777To verify the contents of the image (or check for corruption): 3778 3779 -> tools/mkimage -l examples/uImage.TQM850L 3780 Image Name: 2.4.4 kernel for TQM850L 3781 Created: Wed Jul 19 02:34:59 2000 3782 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3783 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3784 Load Address: 0x00000000 3785 Entry Point: 0x00000000 3786 3787NOTE: for embedded systems where boot time is critical you can trade 3788speed for memory and install an UNCOMPRESSED image instead: this 3789needs more space in Flash, but boots much faster since it does not 3790need to be uncompressed: 3791 3792 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 3793 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3794 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3795 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 3796 > examples/uImage.TQM850L-uncompressed 3797 Image Name: 2.4.4 kernel for TQM850L 3798 Created: Wed Jul 19 02:34:59 2000 3799 Image Type: PowerPC Linux Kernel Image (uncompressed) 3800 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3801 Load Address: 0x00000000 3802 Entry Point: 0x00000000 3803 3804 3805Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3806when your kernel is intended to use an initial ramdisk: 3807 3808 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3809 > -A ppc -O linux -T ramdisk -C gzip \ 3810 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3811 Image Name: Simple Ramdisk Image 3812 Created: Wed Jan 12 14:01:50 2000 3813 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3814 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3815 Load Address: 0x00000000 3816 Entry Point: 0x00000000 3817 3818 3819Installing a Linux Image: 3820------------------------- 3821 3822To downloading a U-Boot image over the serial (console) interface, 3823you must convert the image to S-Record format: 3824 3825 objcopy -I binary -O srec examples/image examples/image.srec 3826 3827The 'objcopy' does not understand the information in the U-Boot 3828image header, so the resulting S-Record file will be relative to 3829address 0x00000000. To load it to a given address, you need to 3830specify the target address as 'offset' parameter with the 'loads' 3831command. 3832 3833Example: install the image to address 0x40100000 (which on the 3834TQM8xxL is in the first Flash bank): 3835 3836 => erase 40100000 401FFFFF 3837 3838 .......... done 3839 Erased 8 sectors 3840 3841 => loads 40100000 3842 ## Ready for S-Record download ... 3843 ~>examples/image.srec 3844 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3845 ... 3846 15989 15990 15991 15992 3847 [file transfer complete] 3848 [connected] 3849 ## Start Addr = 0x00000000 3850 3851 3852You can check the success of the download using the 'iminfo' command; 3853this includes a checksum verification so you can be sure no data 3854corruption happened: 3855 3856 => imi 40100000 3857 3858 ## Checking Image at 40100000 ... 3859 Image Name: 2.2.13 for initrd on TQM850L 3860 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3861 Data Size: 335725 Bytes = 327 kB = 0 MB 3862 Load Address: 00000000 3863 Entry Point: 0000000c 3864 Verifying Checksum ... OK 3865 3866 3867Boot Linux: 3868----------- 3869 3870The "bootm" command is used to boot an application that is stored in 3871memory (RAM or Flash). In case of a Linux kernel image, the contents 3872of the "bootargs" environment variable is passed to the kernel as 3873parameters. You can check and modify this variable using the 3874"printenv" and "setenv" commands: 3875 3876 3877 => printenv bootargs 3878 bootargs=root=/dev/ram 3879 3880 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3881 3882 => printenv bootargs 3883 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3884 3885 => bootm 40020000 3886 ## Booting Linux kernel at 40020000 ... 3887 Image Name: 2.2.13 for NFS on TQM850L 3888 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3889 Data Size: 381681 Bytes = 372 kB = 0 MB 3890 Load Address: 00000000 3891 Entry Point: 0000000c 3892 Verifying Checksum ... OK 3893 Uncompressing Kernel Image ... OK 3894 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 3895 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 3896 time_init: decrementer frequency = 187500000/60 3897 Calibrating delay loop... 49.77 BogoMIPS 3898 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 3899 ... 3900 3901If you want to boot a Linux kernel with initial RAM disk, you pass 3902the memory addresses of both the kernel and the initrd image (PPBCOOT 3903format!) to the "bootm" command: 3904 3905 => imi 40100000 40200000 3906 3907 ## Checking Image at 40100000 ... 3908 Image Name: 2.2.13 for initrd on TQM850L 3909 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3910 Data Size: 335725 Bytes = 327 kB = 0 MB 3911 Load Address: 00000000 3912 Entry Point: 0000000c 3913 Verifying Checksum ... OK 3914 3915 ## Checking Image at 40200000 ... 3916 Image Name: Simple Ramdisk Image 3917 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3918 Data Size: 566530 Bytes = 553 kB = 0 MB 3919 Load Address: 00000000 3920 Entry Point: 00000000 3921 Verifying Checksum ... OK 3922 3923 => bootm 40100000 40200000 3924 ## Booting Linux kernel at 40100000 ... 3925 Image Name: 2.2.13 for initrd on TQM850L 3926 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3927 Data Size: 335725 Bytes = 327 kB = 0 MB 3928 Load Address: 00000000 3929 Entry Point: 0000000c 3930 Verifying Checksum ... OK 3931 Uncompressing Kernel Image ... OK 3932 ## Loading RAMDisk Image at 40200000 ... 3933 Image Name: Simple Ramdisk Image 3934 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3935 Data Size: 566530 Bytes = 553 kB = 0 MB 3936 Load Address: 00000000 3937 Entry Point: 00000000 3938 Verifying Checksum ... OK 3939 Loading Ramdisk ... OK 3940 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 3941 Boot arguments: root=/dev/ram 3942 time_init: decrementer frequency = 187500000/60 3943 Calibrating delay loop... 49.77 BogoMIPS 3944 ... 3945 RAMDISK: Compressed image found at block 0 3946 VFS: Mounted root (ext2 filesystem). 3947 3948 bash# 3949 3950Boot Linux and pass a flat device tree: 3951----------- 3952 3953First, U-Boot must be compiled with the appropriate defines. See the section 3954titled "Linux Kernel Interface" above for a more in depth explanation. The 3955following is an example of how to start a kernel and pass an updated 3956flat device tree: 3957 3958=> print oftaddr 3959oftaddr=0x300000 3960=> print oft 3961oft=oftrees/mpc8540ads.dtb 3962=> tftp $oftaddr $oft 3963Speed: 1000, full duplex 3964Using TSEC0 device 3965TFTP from server 192.168.1.1; our IP address is 192.168.1.101 3966Filename 'oftrees/mpc8540ads.dtb'. 3967Load address: 0x300000 3968Loading: # 3969done 3970Bytes transferred = 4106 (100a hex) 3971=> tftp $loadaddr $bootfile 3972Speed: 1000, full duplex 3973Using TSEC0 device 3974TFTP from server 192.168.1.1; our IP address is 192.168.1.2 3975Filename 'uImage'. 3976Load address: 0x200000 3977Loading:############ 3978done 3979Bytes transferred = 1029407 (fb51f hex) 3980=> print loadaddr 3981loadaddr=200000 3982=> print oftaddr 3983oftaddr=0x300000 3984=> bootm $loadaddr - $oftaddr 3985## Booting image at 00200000 ... 3986 Image Name: Linux-2.6.17-dirty 3987 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3988 Data Size: 1029343 Bytes = 1005.2 kB 3989 Load Address: 00000000 3990 Entry Point: 00000000 3991 Verifying Checksum ... OK 3992 Uncompressing Kernel Image ... OK 3993Booting using flat device tree at 0x300000 3994Using MPC85xx ADS machine description 3995Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 3996[snip] 3997 3998 3999More About U-Boot Image Types: 4000------------------------------ 4001 4002U-Boot supports the following image types: 4003 4004 "Standalone Programs" are directly runnable in the environment 4005 provided by U-Boot; it is expected that (if they behave 4006 well) you can continue to work in U-Boot after return from 4007 the Standalone Program. 4008 "OS Kernel Images" are usually images of some Embedded OS which 4009 will take over control completely. Usually these programs 4010 will install their own set of exception handlers, device 4011 drivers, set up the MMU, etc. - this means, that you cannot 4012 expect to re-enter U-Boot except by resetting the CPU. 4013 "RAMDisk Images" are more or less just data blocks, and their 4014 parameters (address, size) are passed to an OS kernel that is 4015 being started. 4016 "Multi-File Images" contain several images, typically an OS 4017 (Linux) kernel image and one or more data images like 4018 RAMDisks. This construct is useful for instance when you want 4019 to boot over the network using BOOTP etc., where the boot 4020 server provides just a single image file, but you want to get 4021 for instance an OS kernel and a RAMDisk image. 4022 4023 "Multi-File Images" start with a list of image sizes, each 4024 image size (in bytes) specified by an "uint32_t" in network 4025 byte order. This list is terminated by an "(uint32_t)0". 4026 Immediately after the terminating 0 follow the images, one by 4027 one, all aligned on "uint32_t" boundaries (size rounded up to 4028 a multiple of 4 bytes). 4029 4030 "Firmware Images" are binary images containing firmware (like 4031 U-Boot or FPGA images) which usually will be programmed to 4032 flash memory. 4033 4034 "Script files" are command sequences that will be executed by 4035 U-Boot's command interpreter; this feature is especially 4036 useful when you configure U-Boot to use a real shell (hush) 4037 as command interpreter. 4038 4039 4040Standalone HOWTO: 4041================= 4042 4043One of the features of U-Boot is that you can dynamically load and 4044run "standalone" applications, which can use some resources of 4045U-Boot like console I/O functions or interrupt services. 4046 4047Two simple examples are included with the sources: 4048 4049"Hello World" Demo: 4050------------------- 4051 4052'examples/hello_world.c' contains a small "Hello World" Demo 4053application; it is automatically compiled when you build U-Boot. 4054It's configured to run at address 0x00040004, so you can play with it 4055like that: 4056 4057 => loads 4058 ## Ready for S-Record download ... 4059 ~>examples/hello_world.srec 4060 1 2 3 4 5 6 7 8 9 10 11 ... 4061 [file transfer complete] 4062 [connected] 4063 ## Start Addr = 0x00040004 4064 4065 => go 40004 Hello World! This is a test. 4066 ## Starting application at 0x00040004 ... 4067 Hello World 4068 argc = 7 4069 argv[0] = "40004" 4070 argv[1] = "Hello" 4071 argv[2] = "World!" 4072 argv[3] = "This" 4073 argv[4] = "is" 4074 argv[5] = "a" 4075 argv[6] = "test." 4076 argv[7] = "<NULL>" 4077 Hit any key to exit ... 4078 4079 ## Application terminated, rc = 0x0 4080 4081Another example, which demonstrates how to register a CPM interrupt 4082handler with the U-Boot code, can be found in 'examples/timer.c'. 4083Here, a CPM timer is set up to generate an interrupt every second. 4084The interrupt service routine is trivial, just printing a '.' 4085character, but this is just a demo program. The application can be 4086controlled by the following keys: 4087 4088 ? - print current values og the CPM Timer registers 4089 b - enable interrupts and start timer 4090 e - stop timer and disable interrupts 4091 q - quit application 4092 4093 => loads 4094 ## Ready for S-Record download ... 4095 ~>examples/timer.srec 4096 1 2 3 4 5 6 7 8 9 10 11 ... 4097 [file transfer complete] 4098 [connected] 4099 ## Start Addr = 0x00040004 4100 4101 => go 40004 4102 ## Starting application at 0x00040004 ... 4103 TIMERS=0xfff00980 4104 Using timer 1 4105 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 4106 4107Hit 'b': 4108 [q, b, e, ?] Set interval 1000000 us 4109 Enabling timer 4110Hit '?': 4111 [q, b, e, ?] ........ 4112 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 4113Hit '?': 4114 [q, b, e, ?] . 4115 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 4116Hit '?': 4117 [q, b, e, ?] . 4118 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 4119Hit '?': 4120 [q, b, e, ?] . 4121 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 4122Hit 'e': 4123 [q, b, e, ?] ...Stopping timer 4124Hit 'q': 4125 [q, b, e, ?] ## Application terminated, rc = 0x0 4126 4127 4128Minicom warning: 4129================ 4130 4131Over time, many people have reported problems when trying to use the 4132"minicom" terminal emulation program for serial download. I (wd) 4133consider minicom to be broken, and recommend not to use it. Under 4134Unix, I recommend to use C-Kermit for general purpose use (and 4135especially for kermit binary protocol download ("loadb" command), and 4136use "cu" for S-Record download ("loads" command). 4137 4138Nevertheless, if you absolutely want to use it try adding this 4139configuration to your "File transfer protocols" section: 4140 4141 Name Program Name U/D FullScr IO-Red. Multi 4142 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 4143 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 4144 4145 4146NetBSD Notes: 4147============= 4148 4149Starting at version 0.9.2, U-Boot supports NetBSD both as host 4150(build U-Boot) and target system (boots NetBSD/mpc8xx). 4151 4152Building requires a cross environment; it is known to work on 4153NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 4154need gmake since the Makefiles are not compatible with BSD make). 4155Note that the cross-powerpc package does not install include files; 4156attempting to build U-Boot will fail because <machine/ansi.h> is 4157missing. This file has to be installed and patched manually: 4158 4159 # cd /usr/pkg/cross/powerpc-netbsd/include 4160 # mkdir powerpc 4161 # ln -s powerpc machine 4162 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 4163 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 4164 4165Native builds *don't* work due to incompatibilities between native 4166and U-Boot include files. 4167 4168Booting assumes that (the first part of) the image booted is a 4169stage-2 loader which in turn loads and then invokes the kernel 4170proper. Loader sources will eventually appear in the NetBSD source 4171tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 4172meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 4173 4174 4175Implementation Internals: 4176========================= 4177 4178The following is not intended to be a complete description of every 4179implementation detail. However, it should help to understand the 4180inner workings of U-Boot and make it easier to port it to custom 4181hardware. 4182 4183 4184Initial Stack, Global Data: 4185--------------------------- 4186 4187The implementation of U-Boot is complicated by the fact that U-Boot 4188starts running out of ROM (flash memory), usually without access to 4189system RAM (because the memory controller is not initialized yet). 4190This means that we don't have writable Data or BSS segments, and BSS 4191is not initialized as zero. To be able to get a C environment working 4192at all, we have to allocate at least a minimal stack. Implementation 4193options for this are defined and restricted by the CPU used: Some CPU 4194models provide on-chip memory (like the IMMR area on MPC8xx and 4195MPC826x processors), on others (parts of) the data cache can be 4196locked as (mis-) used as memory, etc. 4197 4198 Chris Hallinan posted a good summary of these issues to the 4199 U-Boot mailing list: 4200 4201 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 4202 From: "Chris Hallinan" <clh@net1plus.com> 4203 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 4204 ... 4205 4206 Correct me if I'm wrong, folks, but the way I understand it 4207 is this: Using DCACHE as initial RAM for Stack, etc, does not 4208 require any physical RAM backing up the cache. The cleverness 4209 is that the cache is being used as a temporary supply of 4210 necessary storage before the SDRAM controller is setup. It's 4211 beyond the scope of this list to explain the details, but you 4212 can see how this works by studying the cache architecture and 4213 operation in the architecture and processor-specific manuals. 4214 4215 OCM is On Chip Memory, which I believe the 405GP has 4K. It 4216 is another option for the system designer to use as an 4217 initial stack/RAM area prior to SDRAM being available. Either 4218 option should work for you. Using CS 4 should be fine if your 4219 board designers haven't used it for something that would 4220 cause you grief during the initial boot! It is frequently not 4221 used. 4222 4223 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 4224 with your processor/board/system design. The default value 4225 you will find in any recent u-boot distribution in 4226 walnut.h should work for you. I'd set it to a value larger 4227 than your SDRAM module. If you have a 64MB SDRAM module, set 4228 it above 400_0000. Just make sure your board has no resources 4229 that are supposed to respond to that address! That code in 4230 start.S has been around a while and should work as is when 4231 you get the config right. 4232 4233 -Chris Hallinan 4234 DS4.COM, Inc. 4235 4236It is essential to remember this, since it has some impact on the C 4237code for the initialization procedures: 4238 4239* Initialized global data (data segment) is read-only. Do not attempt 4240 to write it. 4241 4242* Do not use any uninitialized global data (or implicitely initialized 4243 as zero data - BSS segment) at all - this is undefined, initiali- 4244 zation is performed later (when relocating to RAM). 4245 4246* Stack space is very limited. Avoid big data buffers or things like 4247 that. 4248 4249Having only the stack as writable memory limits means we cannot use 4250normal global data to share information beween the code. But it 4251turned out that the implementation of U-Boot can be greatly 4252simplified by making a global data structure (gd_t) available to all 4253functions. We could pass a pointer to this data as argument to _all_ 4254functions, but this would bloat the code. Instead we use a feature of 4255the GCC compiler (Global Register Variables) to share the data: we 4256place a pointer (gd) to the global data into a register which we 4257reserve for this purpose. 4258 4259When choosing a register for such a purpose we are restricted by the 4260relevant (E)ABI specifications for the current architecture, and by 4261GCC's implementation. 4262 4263For PowerPC, the following registers have specific use: 4264 R1: stack pointer 4265 R2: reserved for system use 4266 R3-R4: parameter passing and return values 4267 R5-R10: parameter passing 4268 R13: small data area pointer 4269 R30: GOT pointer 4270 R31: frame pointer 4271 4272 (U-Boot also uses R12 as internal GOT pointer. r12 4273 is a volatile register so r12 needs to be reset when 4274 going back and forth between asm and C) 4275 4276 ==> U-Boot will use R2 to hold a pointer to the global data 4277 4278 Note: on PPC, we could use a static initializer (since the 4279 address of the global data structure is known at compile time), 4280 but it turned out that reserving a register results in somewhat 4281 smaller code - although the code savings are not that big (on 4282 average for all boards 752 bytes for the whole U-Boot image, 4283 624 text + 127 data). 4284 4285On Blackfin, the normal C ABI (except for P3) is followed as documented here: 4286 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 4287 4288 ==> U-Boot will use P3 to hold a pointer to the global data 4289 4290On ARM, the following registers are used: 4291 4292 R0: function argument word/integer result 4293 R1-R3: function argument word 4294 R9: GOT pointer 4295 R10: stack limit (used only if stack checking if enabled) 4296 R11: argument (frame) pointer 4297 R12: temporary workspace 4298 R13: stack pointer 4299 R14: link register 4300 R15: program counter 4301 4302 ==> U-Boot will use R8 to hold a pointer to the global data 4303 4304On Nios II, the ABI is documented here: 4305 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 4306 4307 ==> U-Boot will use gp to hold a pointer to the global data 4308 4309 Note: on Nios II, we give "-G0" option to gcc and don't use gp 4310 to access small data sections, so gp is free. 4311 4312NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 4313or current versions of GCC may "optimize" the code too much. 4314 4315Memory Management: 4316------------------ 4317 4318U-Boot runs in system state and uses physical addresses, i.e. the 4319MMU is not used either for address mapping nor for memory protection. 4320 4321The available memory is mapped to fixed addresses using the memory 4322controller. In this process, a contiguous block is formed for each 4323memory type (Flash, SDRAM, SRAM), even when it consists of several 4324physical memory banks. 4325 4326U-Boot is installed in the first 128 kB of the first Flash bank (on 4327TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 4328booting and sizing and initializing DRAM, the code relocates itself 4329to the upper end of DRAM. Immediately below the U-Boot code some 4330memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 4331configuration setting]. Below that, a structure with global Board 4332Info data is placed, followed by the stack (growing downward). 4333 4334Additionally, some exception handler code is copied to the low 8 kB 4335of DRAM (0x00000000 ... 0x00001FFF). 4336 4337So a typical memory configuration with 16 MB of DRAM could look like 4338this: 4339 4340 0x0000 0000 Exception Vector code 4341 : 4342 0x0000 1FFF 4343 0x0000 2000 Free for Application Use 4344 : 4345 : 4346 4347 : 4348 : 4349 0x00FB FF20 Monitor Stack (Growing downward) 4350 0x00FB FFAC Board Info Data and permanent copy of global data 4351 0x00FC 0000 Malloc Arena 4352 : 4353 0x00FD FFFF 4354 0x00FE 0000 RAM Copy of Monitor Code 4355 ... eventually: LCD or video framebuffer 4356 ... eventually: pRAM (Protected RAM - unchanged by reset) 4357 0x00FF FFFF [End of RAM] 4358 4359 4360System Initialization: 4361---------------------- 4362 4363In the reset configuration, U-Boot starts at the reset entry point 4364(on most PowerPC systems at address 0x00000100). Because of the reset 4365configuration for CS0# this is a mirror of the onboard Flash memory. 4366To be able to re-map memory U-Boot then jumps to its link address. 4367To be able to implement the initialization code in C, a (small!) 4368initial stack is set up in the internal Dual Ported RAM (in case CPUs 4369which provide such a feature like MPC8xx or MPC8260), or in a locked 4370part of the data cache. After that, U-Boot initializes the CPU core, 4371the caches and the SIU. 4372 4373Next, all (potentially) available memory banks are mapped using a 4374preliminary mapping. For example, we put them on 512 MB boundaries 4375(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 4376on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 4377programmed for SDRAM access. Using the temporary configuration, a 4378simple memory test is run that determines the size of the SDRAM 4379banks. 4380 4381When there is more than one SDRAM bank, and the banks are of 4382different size, the largest is mapped first. For equal size, the first 4383bank (CS2#) is mapped first. The first mapping is always for address 43840x00000000, with any additional banks following immediately to create 4385contiguous memory starting from 0. 4386 4387Then, the monitor installs itself at the upper end of the SDRAM area 4388and allocates memory for use by malloc() and for the global Board 4389Info data; also, the exception vector code is copied to the low RAM 4390pages, and the final stack is set up. 4391 4392Only after this relocation will you have a "normal" C environment; 4393until that you are restricted in several ways, mostly because you are 4394running from ROM, and because the code will have to be relocated to a 4395new address in RAM. 4396 4397 4398U-Boot Porting Guide: 4399---------------------- 4400 4401[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 4402list, October 2002] 4403 4404 4405int main(int argc, char *argv[]) 4406{ 4407 sighandler_t no_more_time; 4408 4409 signal(SIGALRM, no_more_time); 4410 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 4411 4412 if (available_money > available_manpower) { 4413 Pay consultant to port U-Boot; 4414 return 0; 4415 } 4416 4417 Download latest U-Boot source; 4418 4419 Subscribe to u-boot mailing list; 4420 4421 if (clueless) 4422 email("Hi, I am new to U-Boot, how do I get started?"); 4423 4424 while (learning) { 4425 Read the README file in the top level directory; 4426 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 4427 Read applicable doc/*.README; 4428 Read the source, Luke; 4429 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 4430 } 4431 4432 if (available_money > toLocalCurrency ($2500)) 4433 Buy a BDI3000; 4434 else 4435 Add a lot of aggravation and time; 4436 4437 if (a similar board exists) { /* hopefully... */ 4438 cp -a board/<similar> board/<myboard> 4439 cp include/configs/<similar>.h include/configs/<myboard>.h 4440 } else { 4441 Create your own board support subdirectory; 4442 Create your own board include/configs/<myboard>.h file; 4443 } 4444 Edit new board/<myboard> files 4445 Edit new include/configs/<myboard>.h 4446 4447 while (!accepted) { 4448 while (!running) { 4449 do { 4450 Add / modify source code; 4451 } until (compiles); 4452 Debug; 4453 if (clueless) 4454 email("Hi, I am having problems..."); 4455 } 4456 Send patch file to the U-Boot email list; 4457 if (reasonable critiques) 4458 Incorporate improvements from email list code review; 4459 else 4460 Defend code as written; 4461 } 4462 4463 return 0; 4464} 4465 4466void no_more_time (int sig) 4467{ 4468 hire_a_guru(); 4469} 4470 4471 4472Coding Standards: 4473----------------- 4474 4475All contributions to U-Boot should conform to the Linux kernel 4476coding style; see the file "Documentation/CodingStyle" and the script 4477"scripts/Lindent" in your Linux kernel source directory. In sources 4478originating from U-Boot a style corresponding to "Lindent -pcs" (adding 4479spaces before parameters to function calls) is actually used. 4480 4481Source files originating from a different project (for example the 4482MTD subsystem) are generally exempt from these guidelines and are not 4483reformated to ease subsequent migration to newer versions of those 4484sources. 4485 4486Please note that U-Boot is implemented in C (and to some small parts in 4487Assembler); no C++ is used, so please do not use C++ style comments (//) 4488in your code. 4489 4490Please also stick to the following formatting rules: 4491- remove any trailing white space 4492- use TAB characters for indentation, not spaces 4493- make sure NOT to use DOS '\r\n' line feeds 4494- do not add more than 2 empty lines to source files 4495- do not add trailing empty lines to source files 4496 4497Submissions which do not conform to the standards may be returned 4498with a request to reformat the changes. 4499 4500 4501Submitting Patches: 4502------------------- 4503 4504Since the number of patches for U-Boot is growing, we need to 4505establish some rules. Submissions which do not conform to these rules 4506may be rejected, even when they contain important and valuable stuff. 4507 4508Please see http://www.denx.de/wiki/U-Boot/Patches for details. 4509 4510Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 4511see http://lists.denx.de/mailman/listinfo/u-boot 4512 4513When you send a patch, please include the following information with 4514it: 4515 4516* For bug fixes: a description of the bug and how your patch fixes 4517 this bug. Please try to include a way of demonstrating that the 4518 patch actually fixes something. 4519 4520* For new features: a description of the feature and your 4521 implementation. 4522 4523* A CHANGELOG entry as plaintext (separate from the patch) 4524 4525* For major contributions, your entry to the CREDITS file 4526 4527* When you add support for a new board, don't forget to add this 4528 board to the MAKEALL script, too. 4529 4530* If your patch adds new configuration options, don't forget to 4531 document these in the README file. 4532 4533* The patch itself. If you are using git (which is *strongly* 4534 recommended) you can easily generate the patch using the 4535 "git-format-patch". If you then use "git-send-email" to send it to 4536 the U-Boot mailing list, you will avoid most of the common problems 4537 with some other mail clients. 4538 4539 If you cannot use git, use "diff -purN OLD NEW". If your version of 4540 diff does not support these options, then get the latest version of 4541 GNU diff. 4542 4543 The current directory when running this command shall be the parent 4544 directory of the U-Boot source tree (i. e. please make sure that 4545 your patch includes sufficient directory information for the 4546 affected files). 4547 4548 We prefer patches as plain text. MIME attachments are discouraged, 4549 and compressed attachments must not be used. 4550 4551* If one logical set of modifications affects or creates several 4552 files, all these changes shall be submitted in a SINGLE patch file. 4553 4554* Changesets that contain different, unrelated modifications shall be 4555 submitted as SEPARATE patches, one patch per changeset. 4556 4557 4558Notes: 4559 4560* Before sending the patch, run the MAKEALL script on your patched 4561 source tree and make sure that no errors or warnings are reported 4562 for any of the boards. 4563 4564* Keep your modifications to the necessary minimum: A patch 4565 containing several unrelated changes or arbitrary reformats will be 4566 returned with a request to re-formatting / split it. 4567 4568* If you modify existing code, make sure that your new code does not 4569 add to the memory footprint of the code ;-) Small is beautiful! 4570 When adding new features, these should compile conditionally only 4571 (using #ifdef), and the resulting code with the new feature 4572 disabled must not need more memory than the old code without your 4573 modification. 4574 4575* Remember that there is a size limit of 100 kB per message on the 4576 u-boot mailing list. Bigger patches will be moderated. If they are 4577 reasonable and not too big, they will be acknowledged. But patches 4578 bigger than the size limit should be avoided. 4579