1# 2# (C) Copyright 2000 - 2004 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 and ARM processors, which can be 29installed in a boot ROM and used to initialize and test the hardware 30or to download and run application code. 31 32The development of U-Boot is closely related to Linux: some parts of 33the source code originate in the Linux source tree, we have some 34header files in common, and special provision has been made to 35support booting of Linux images. 36 37Some attention has been paid to make this software easily 38configurable and extendable. For instance, all monitor commands are 39implemented with the same call interface, so that it's very easy to 40add new commands. Also, instead of permanently adding rarely used 41code (for instance hardware test utilities) to the monitor, you can 42load and run it dynamically. 43 44 45Status: 46======= 47 48In general, all boards for which a configuration option exists in the 49Makefile have been tested to some extent and can be considered 50"working". In fact, many of them are used in production systems. 51 52In case of problems see the CHANGELOG and CREDITS files to find out 53who contributed the specific port. 54 55 56Where to get help: 57================== 58 59In case you have questions about, problems with or contributions for 60U-Boot you should send a message to the U-Boot mailing list at 61<u-boot-users@lists.sourceforge.net>. There is also an archive of 62previous traffic on the mailing list - please search the archive 63before asking FAQ's. Please see 64http://lists.sourceforge.net/lists/listinfo/u-boot-users/ 65 66 67Where we come from: 68=================== 69 70- start from 8xxrom sources 71- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 72- clean up code 73- make it easier to add custom boards 74- make it possible to add other [PowerPC] CPUs 75- extend functions, especially: 76 * Provide extended interface to Linux boot loader 77 * S-Record download 78 * network boot 79 * PCMCIA / CompactFLash / ATA disk / SCSI ... boot 80- create ARMBoot project (http://sourceforge.net/projects/armboot) 81- add other CPU families (starting with ARM) 82- create U-Boot project (http://sourceforge.net/projects/u-boot) 83 84 85Names and Spelling: 86=================== 87 88The "official" name of this project is "Das U-Boot". The spelling 89"U-Boot" shall be used in all written text (documentation, comments 90in source files etc.). Example: 91 92 This is the README file for the U-Boot project. 93 94File names etc. shall be based on the string "u-boot". Examples: 95 96 include/asm-ppc/u-boot.h 97 98 #include <asm/u-boot.h> 99 100Variable names, preprocessor constants etc. shall be either based on 101the string "u_boot" or on "U_BOOT". Example: 102 103 U_BOOT_VERSION u_boot_logo 104 IH_OS_U_BOOT u_boot_hush_start 105 106 107Versioning: 108=========== 109 110U-Boot uses a 3 level version number containing a version, a 111sub-version, and a patchlevel: "U-Boot-2.34.5" means version "2", 112sub-version "34", and patchlevel "4". 113 114The patchlevel is used to indicate certain stages of development 115between released versions, i. e. officially released versions of 116U-Boot will always have a patchlevel of "0". 117 118 119Directory Hierarchy: 120==================== 121 122- board Board dependent files 123- common Misc architecture independent functions 124- cpu CPU specific files 125 - 74xx_7xx Files specific to Motorola MPC74xx and 7xx CPUs 126 - arm720t Files specific to ARM 720 CPUs 127 - arm920t Files specific to ARM 920 CPUs 128 - arm925t Files specific to ARM 925 CPUs 129 - arm926ejs Files specific to ARM 926 CPUs 130 - at91rm9200 Files specific to Atmel AT91RM9200 CPUs 131 - i386 Files specific to i386 CPUs 132 - ixp Files specific to Intel XScale IXP CPUs 133 - mcf52x2 Files specific to Motorola ColdFire MCF52x2 CPUs 134 - mips Files specific to MIPS CPUs 135 - mpc5xx Files specific to Motorola MPC5xx CPUs 136 - mpc5xxx Files specific to Motorola MPC5xxx CPUs 137 - mpc8xx Files specific to Motorola MPC8xx CPUs 138 - mpc824x Files specific to Motorola MPC824x CPUs 139 - mpc8260 Files specific to Motorola MPC8260 CPUs 140 - mpc85xx Files specific to Motorola MPC85xx CPUs 141 - nios Files specific to Altera NIOS CPUs 142 - ppc4xx Files specific to IBM PowerPC 4xx CPUs 143 - pxa Files specific to Intel XScale PXA CPUs 144 - s3c44b0 Files specific to Samsung S3C44B0 CPUs 145 - sa1100 Files specific to Intel StrongARM SA1100 CPUs 146- disk Code for disk drive partition handling 147- doc Documentation (don't expect too much) 148- drivers Commonly used device drivers 149- dtt Digital Thermometer and Thermostat drivers 150- examples Example code for standalone applications, etc. 151- include Header Files 152- lib_arm Files generic to ARM architecture 153- lib_generic Files generic to all architectures 154- lib_i386 Files generic to i386 architecture 155- lib_m68k Files generic to m68k architecture 156- lib_mips Files generic to MIPS architecture 157- lib_nios Files generic to NIOS architecture 158- lib_ppc Files generic to PowerPC architecture 159- net Networking code 160- post Power On Self Test 161- rtc Real Time Clock drivers 162- tools Tools to build S-Record or U-Boot images, etc. 163 164Software Configuration: 165======================= 166 167Configuration is usually done using C preprocessor defines; the 168rationale behind that is to avoid dead code whenever possible. 169 170There are two classes of configuration variables: 171 172* Configuration _OPTIONS_: 173 These are selectable by the user and have names beginning with 174 "CONFIG_". 175 176* Configuration _SETTINGS_: 177 These depend on the hardware etc. and should not be meddled with if 178 you don't know what you're doing; they have names beginning with 179 "CFG_". 180 181Later we will add a configuration tool - probably similar to or even 182identical to what's used for the Linux kernel. Right now, we have to 183do the configuration by hand, which means creating some symbolic 184links and editing some configuration files. We use the TQM8xxL boards 185as an example here. 186 187 188Selection of Processor Architecture and Board Type: 189--------------------------------------------------- 190 191For all supported boards there are ready-to-use default 192configurations available; just type "make <board_name>_config". 193 194Example: For a TQM823L module type: 195 196 cd u-boot 197 make TQM823L_config 198 199For the Cogent platform, you need to specify the cpu type as well; 200e.g. "make cogent_mpc8xx_config". And also configure the cogent 201directory according to the instructions in cogent/README. 202 203 204Configuration Options: 205---------------------- 206 207Configuration depends on the combination of board and CPU type; all 208such information is kept in a configuration file 209"include/configs/<board_name>.h". 210 211Example: For a TQM823L module, all configuration settings are in 212"include/configs/TQM823L.h". 213 214 215Many of the options are named exactly as the corresponding Linux 216kernel configuration options. The intention is to make it easier to 217build a config tool - later. 218 219 220The following options need to be configured: 221 222- CPU Type: Define exactly one of 223 224 PowerPC based CPUs: 225 ------------------- 226 CONFIG_MPC823, CONFIG_MPC850, CONFIG_MPC855, CONFIG_MPC860 227 or CONFIG_MPC5xx 228 or CONFIG_MPC824X, CONFIG_MPC8260 229 or CONFIG_MPC85xx 230 or CONFIG_IOP480 231 or CONFIG_405GP 232 or CONFIG_405EP 233 or CONFIG_440 234 or CONFIG_MPC74xx 235 or CONFIG_750FX 236 237 ARM based CPUs: 238 --------------- 239 CONFIG_SA1110 240 CONFIG_ARM7 241 CONFIG_PXA250 242 243 244- Board Type: Define exactly one of 245 246 PowerPC based boards: 247 --------------------- 248 249 CONFIG_ADCIOP, CONFIG_ICU862 CONFIG_RPXsuper, 250 CONFIG_ADS860, CONFIG_IP860, CONFIG_SM850, 251 CONFIG_AMX860, CONFIG_IPHASE4539, CONFIG_SPD823TS, 252 CONFIG_AR405, CONFIG_IVML24, CONFIG_SXNI855T, 253 CONFIG_BAB7xx, CONFIG_IVML24_128, CONFIG_Sandpoint8240, 254 CONFIG_CANBT, CONFIG_IVML24_256, CONFIG_Sandpoint8245, 255 CONFIG_CCM, CONFIG_IVMS8, CONFIG_TQM823L, 256 CONFIG_CPCI405, CONFIG_IVMS8_128, CONFIG_TQM850L, 257 CONFIG_CPCI4052, CONFIG_IVMS8_256, CONFIG_TQM855L, 258 CONFIG_CPCIISER4, CONFIG_LANTEC, CONFIG_TQM860L, 259 CONFIG_CPU86, CONFIG_MBX, CONFIG_TQM8260, 260 CONFIG_CRAYL1, CONFIG_MBX860T, CONFIG_TTTech, 261 CONFIG_CU824, CONFIG_MHPC, CONFIG_UTX8245, 262 CONFIG_DASA_SIM, CONFIG_MIP405, CONFIG_W7OLMC, 263 CONFIG_DU405, CONFIG_MOUSSE, CONFIG_W7OLMG, 264 CONFIG_ELPPC, CONFIG_MPC8260ADS, CONFIG_WALNUT405, 265 CONFIG_ERIC, CONFIG_MUSENKI, CONFIG_ZUMA, 266 CONFIG_ESTEEM192E, CONFIG_MVS1, CONFIG_c2mon, 267 CONFIG_ETX094, CONFIG_NX823, CONFIG_cogent_mpc8260, 268 CONFIG_EVB64260, CONFIG_OCRTC, CONFIG_cogent_mpc8xx, 269 CONFIG_FADS823, CONFIG_ORSG, CONFIG_ep8260, 270 CONFIG_FADS850SAR, CONFIG_OXC, CONFIG_gw8260, 271 CONFIG_FADS860T, CONFIG_PCI405, CONFIG_hermes, 272 CONFIG_FLAGADM, CONFIG_PCIPPC2, CONFIG_hymod, 273 CONFIG_FPS850L, CONFIG_PCIPPC6, CONFIG_lwmon, 274 CONFIG_GEN860T, CONFIG_PIP405, CONFIG_pcu_e, 275 CONFIG_GENIETV, CONFIG_PM826, CONFIG_ppmc8260, 276 CONFIG_GTH, CONFIG_RPXClassic, CONFIG_rsdproto, 277 CONFIG_IAD210, CONFIG_RPXlite, CONFIG_sbc8260, 278 CONFIG_EBONY, CONFIG_sacsng, CONFIG_FPS860L, 279 CONFIG_V37, CONFIG_ELPT860, CONFIG_CMI, 280 CONFIG_NETVIA, CONFIG_RBC823, CONFIG_ZPC1900, 281 CONFIG_MPC8540ADS, CONFIG_MPC8560ADS, CONFIG_QS850, 282 CONFIG_QS823, CONFIG_QS860T, CONFIG_DB64360, 283 CONFIG_DB64460, CONFIG_DUET_ADS 284 285 ARM based boards: 286 ----------------- 287 288 CONFIG_HHP_CRADLE, CONFIG_DNP1110, CONFIG_EP7312, 289 CONFIG_IMPA7, CONFIG_LART, CONFIG_LUBBOCK, 290 CONFIG_INNOVATOROMAP1510, CONFIG_INNOVATOROMAP1610, 291 CONFIG_H2_OMAP1610, CONFIG_SHANNON, CONFIG_SMDK2400, 292 CONFIG_SMDK2410, CONFIG_TRAB, CONFIG_VCMA9, 293 CONFIG_AT91RM9200DK 294 295 296- CPU Module Type: (if CONFIG_COGENT is defined) 297 Define exactly one of 298 CONFIG_CMA286_60_OLD 299--- FIXME --- not tested yet: 300 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 301 CONFIG_CMA287_23, CONFIG_CMA287_50 302 303- Motherboard Type: (if CONFIG_COGENT is defined) 304 Define exactly one of 305 CONFIG_CMA101, CONFIG_CMA102 306 307- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 308 Define one or more of 309 CONFIG_CMA302 310 311- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 312 Define one or more of 313 CONFIG_LCD_HEARTBEAT - update a character position on 314 the lcd display every second with 315 a "rotator" |\-/|\-/ 316 317- Board flavour: (if CONFIG_MPC8260ADS is defined) 318 CONFIG_ADSTYPE 319 Possible values are: 320 CFG_8260ADS - original MPC8260ADS 321 CFG_8266ADS - MPC8266ADS 322 CFG_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 323 324 325- MPC824X Family Member (if CONFIG_MPC824X is defined) 326 Define exactly one of 327 CONFIG_MPC8240, CONFIG_MPC8245 328 329- 8xx CPU Options: (if using an MPC8xx cpu) 330 Define one or more of 331 CONFIG_8xx_GCLK_FREQ - if get_gclk_freq() cannot work 332 e.g. if there is no 32KHz 333 reference PIT/RTC clock 334 335- 859/866 CPU options: (if using a MPC859 or MPC866 CPU): 336 CFG_866_OSCCLK 337 CFG_866_CPUCLK_MIN 338 CFG_866_CPUCLK_MAX 339 CFG_866_CPUCLK_DEFAULT 340 See doc/README.MPC866 341 342 CFG_MEASURE_CPUCLK 343 344 Define this to measure the actual CPU clock instead 345 of relying on the correctness of the configured 346 values. Mostly useful for board bringup to make sure 347 the PLL is locked at the intended frequency. Note 348 that this requires a (stable) reference clock (32 kHz 349 RTC clock), 350 351- Linux Kernel Interface: 352 CONFIG_CLOCKS_IN_MHZ 353 354 U-Boot stores all clock information in Hz 355 internally. For binary compatibility with older Linux 356 kernels (which expect the clocks passed in the 357 bd_info data to be in MHz) the environment variable 358 "clocks_in_mhz" can be defined so that U-Boot 359 converts clock data to MHZ before passing it to the 360 Linux kernel. 361 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 362 "clocks_in_mhz=1" is automatically included in the 363 default environment. 364 365 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 366 367 When transfering memsize parameter to linux, some versions 368 expect it to be in bytes, others in MB. 369 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 370 371- Console Interface: 372 Depending on board, define exactly one serial port 373 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 374 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 375 console by defining CONFIG_8xx_CONS_NONE 376 377 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 378 port routines must be defined elsewhere 379 (i.e. serial_init(), serial_getc(), ...) 380 381 CONFIG_CFB_CONSOLE 382 Enables console device for a color framebuffer. Needs following 383 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 384 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 385 (default big endian) 386 VIDEO_HW_RECTFILL graphic chip supports 387 rectangle fill 388 (cf. smiLynxEM) 389 VIDEO_HW_BITBLT graphic chip supports 390 bit-blit (cf. smiLynxEM) 391 VIDEO_VISIBLE_COLS visible pixel columns 392 (cols=pitch) 393 VIDEO_VISIBLE_ROWS visible pixel rows 394 VIDEO_PIXEL_SIZE bytes per pixel 395 VIDEO_DATA_FORMAT graphic data format 396 (0-5, cf. cfb_console.c) 397 VIDEO_FB_ADRS framebuffer address 398 VIDEO_KBD_INIT_FCT keyboard int fct 399 (i.e. i8042_kbd_init()) 400 VIDEO_TSTC_FCT test char fct 401 (i.e. i8042_tstc) 402 VIDEO_GETC_FCT get char fct 403 (i.e. i8042_getc) 404 CONFIG_CONSOLE_CURSOR cursor drawing on/off 405 (requires blink timer 406 cf. i8042.c) 407 CFG_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 408 CONFIG_CONSOLE_TIME display time/date info in 409 upper right corner 410 (requires CFG_CMD_DATE) 411 CONFIG_VIDEO_LOGO display Linux logo in 412 upper left corner 413 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 414 linux_logo.h for logo. 415 Requires CONFIG_VIDEO_LOGO 416 CONFIG_CONSOLE_EXTRA_INFO 417 addional board info beside 418 the logo 419 420 When CONFIG_CFB_CONSOLE is defined, video console is 421 default i/o. Serial console can be forced with 422 environment 'console=serial'. 423 424 When CONFIG_SILENT_CONSOLE is defined, all console 425 messages (by U-Boot and Linux!) can be silenced with 426 the "silent" environment variable. See 427 doc/README.silent for more information. 428 429- Console Baudrate: 430 CONFIG_BAUDRATE - in bps 431 Select one of the baudrates listed in 432 CFG_BAUDRATE_TABLE, see below. 433 CFG_BRGCLK_PRESCALE, baudrate prescale 434 435- Interrupt driven serial port input: 436 CONFIG_SERIAL_SOFTWARE_FIFO 437 438 PPC405GP only. 439 Use an interrupt handler for receiving data on the 440 serial port. It also enables using hardware handshake 441 (RTS/CTS) and UART's built-in FIFO. Set the number of 442 bytes the interrupt driven input buffer should have. 443 444 Set to 0 to disable this feature (this is the default). 445 This will also disable hardware handshake. 446 447- Console UART Number: 448 CONFIG_UART1_CONSOLE 449 450 IBM PPC4xx only. 451 If defined internal UART1 (and not UART0) is used 452 as default U-Boot console. 453 454- Boot Delay: CONFIG_BOOTDELAY - in seconds 455 Delay before automatically booting the default image; 456 set to -1 to disable autoboot. 457 458 See doc/README.autoboot for these options that 459 work with CONFIG_BOOTDELAY. None are required. 460 CONFIG_BOOT_RETRY_TIME 461 CONFIG_BOOT_RETRY_MIN 462 CONFIG_AUTOBOOT_KEYED 463 CONFIG_AUTOBOOT_PROMPT 464 CONFIG_AUTOBOOT_DELAY_STR 465 CONFIG_AUTOBOOT_STOP_STR 466 CONFIG_AUTOBOOT_DELAY_STR2 467 CONFIG_AUTOBOOT_STOP_STR2 468 CONFIG_ZERO_BOOTDELAY_CHECK 469 CONFIG_RESET_TO_RETRY 470 471- Autoboot Command: 472 CONFIG_BOOTCOMMAND 473 Only needed when CONFIG_BOOTDELAY is enabled; 474 define a command string that is automatically executed 475 when no character is read on the console interface 476 within "Boot Delay" after reset. 477 478 CONFIG_BOOTARGS 479 This can be used to pass arguments to the bootm 480 command. The value of CONFIG_BOOTARGS goes into the 481 environment value "bootargs". 482 483 CONFIG_RAMBOOT and CONFIG_NFSBOOT 484 The value of these goes into the environment as 485 "ramboot" and "nfsboot" respectively, and can be used 486 as a convenience, when switching between booting from 487 ram and nfs. 488 489- Pre-Boot Commands: 490 CONFIG_PREBOOT 491 492 When this option is #defined, the existence of the 493 environment variable "preboot" will be checked 494 immediately before starting the CONFIG_BOOTDELAY 495 countdown and/or running the auto-boot command resp. 496 entering interactive mode. 497 498 This feature is especially useful when "preboot" is 499 automatically generated or modified. For an example 500 see the LWMON board specific code: here "preboot" is 501 modified when the user holds down a certain 502 combination of keys on the (special) keyboard when 503 booting the systems 504 505- Serial Download Echo Mode: 506 CONFIG_LOADS_ECHO 507 If defined to 1, all characters received during a 508 serial download (using the "loads" command) are 509 echoed back. This might be needed by some terminal 510 emulations (like "cu"), but may as well just take 511 time on others. This setting #define's the initial 512 value of the "loads_echo" environment variable. 513 514- Kgdb Serial Baudrate: (if CFG_CMD_KGDB is defined) 515 CONFIG_KGDB_BAUDRATE 516 Select one of the baudrates listed in 517 CFG_BAUDRATE_TABLE, see below. 518 519- Monitor Functions: 520 CONFIG_COMMANDS 521 Most monitor functions can be selected (or 522 de-selected) by adjusting the definition of 523 CONFIG_COMMANDS; to select individual functions, 524 #define CONFIG_COMMANDS by "OR"ing any of the 525 following values: 526 527 #define enables commands: 528 ------------------------- 529 CFG_CMD_ASKENV * ask for env variable 530 CFG_CMD_AUTOSCRIPT Autoscript Support 531 CFG_CMD_BDI bdinfo 532 CFG_CMD_BEDBUG Include BedBug Debugger 533 CFG_CMD_BMP * BMP support 534 CFG_CMD_BOOTD bootd 535 CFG_CMD_CACHE icache, dcache 536 CFG_CMD_CONSOLE coninfo 537 CFG_CMD_DATE * support for RTC, date/time... 538 CFG_CMD_DHCP DHCP support 539 CFG_CMD_DIAG * Diagnostics 540 CFG_CMD_DOC * Disk-On-Chip Support 541 CFG_CMD_DTT Digital Therm and Thermostat 542 CFG_CMD_ECHO * echo arguments 543 CFG_CMD_EEPROM * EEPROM read/write support 544 CFG_CMD_ELF bootelf, bootvx 545 CFG_CMD_ENV saveenv 546 CFG_CMD_FDC * Floppy Disk Support 547 CFG_CMD_FAT FAT partition support 548 CFG_CMD_FDOS * Dos diskette Support 549 CFG_CMD_FLASH flinfo, erase, protect 550 CFG_CMD_FPGA FPGA device initialization support 551 CFG_CMD_HWFLOW * RTS/CTS hw flow control 552 CFG_CMD_I2C * I2C serial bus support 553 CFG_CMD_IDE * IDE harddisk support 554 CFG_CMD_IMI iminfo 555 CFG_CMD_IMLS List all found images 556 CFG_CMD_IMMAP * IMMR dump support 557 CFG_CMD_IRQ * irqinfo 558 CFG_CMD_ITEST * Integer/string test of 2 values 559 CFG_CMD_JFFS2 * JFFS2 Support 560 CFG_CMD_KGDB * kgdb 561 CFG_CMD_LOADB loadb 562 CFG_CMD_LOADS loads 563 CFG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 564 loop, mtest 565 CFG_CMD_MISC Misc functions like sleep etc 566 CFG_CMD_MMC MMC memory mapped support 567 CFG_CMD_MII MII utility commands 568 CFG_CMD_NAND * NAND support 569 CFG_CMD_NET bootp, tftpboot, rarpboot 570 CFG_CMD_PCI * pciinfo 571 CFG_CMD_PCMCIA * PCMCIA support 572 CFG_CMD_PING * send ICMP ECHO_REQUEST to network host 573 CFG_CMD_PORTIO * Port I/O 574 CFG_CMD_REGINFO * Register dump 575 CFG_CMD_RUN run command in env variable 576 CFG_CMD_SAVES save S record dump 577 CFG_CMD_SCSI * SCSI Support 578 CFG_CMD_SDRAM * print SDRAM configuration information 579 CFG_CMD_SETGETDCR Support for DCR Register access (4xx only) 580 CFG_CMD_SPI * SPI serial bus support 581 CFG_CMD_USB * USB support 582 CFG_CMD_VFD * VFD support (TRAB) 583 CFG_CMD_BSP * Board SPecific functions 584 ----------------------------------------------- 585 CFG_CMD_ALL all 586 587 CFG_CMD_DFL Default configuration; at the moment 588 this is includes all commands, except 589 the ones marked with "*" in the list 590 above. 591 592 If you don't define CONFIG_COMMANDS it defaults to 593 CFG_CMD_DFL in include/cmd_confdefs.h. A board can 594 override the default settings in the respective 595 include file. 596 597 EXAMPLE: If you want all functions except of network 598 support you can write: 599 600 #define CONFIG_COMMANDS (CFG_CMD_ALL & ~CFG_CMD_NET) 601 602 603 Note: Don't enable the "icache" and "dcache" commands 604 (configuration option CFG_CMD_CACHE) unless you know 605 what you (and your U-Boot users) are doing. Data 606 cache cannot be enabled on systems like the 8xx or 607 8260 (where accesses to the IMMR region must be 608 uncached), and it cannot be disabled on all other 609 systems where we (mis-) use the data cache to hold an 610 initial stack and some data. 611 612 613 XXX - this list needs to get updated! 614 615- Watchdog: 616 CONFIG_WATCHDOG 617 If this variable is defined, it enables watchdog 618 support. There must be support in the platform specific 619 code for a watchdog. For the 8xx and 8260 CPUs, the 620 SIU Watchdog feature is enabled in the SYPCR 621 register. 622 623- U-Boot Version: 624 CONFIG_VERSION_VARIABLE 625 If this variable is defined, an environment variable 626 named "ver" is created by U-Boot showing the U-Boot 627 version as printed by the "version" command. 628 This variable is readonly. 629 630- Real-Time Clock: 631 632 When CFG_CMD_DATE is selected, the type of the RTC 633 has to be selected, too. Define exactly one of the 634 following options: 635 636 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 637 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 638 CONFIG_RTC_MC146818 - use MC146818 RTC 639 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 640 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 641 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 642 CONFIG_RTC_DS164x - use Dallas DS164x RTC 643 644 Note that if the RTC uses I2C, then the I2C interface 645 must also be configured. See I2C Support, below. 646 647- Timestamp Support: 648 649 When CONFIG_TIMESTAMP is selected, the timestamp 650 (date and time) of an image is printed by image 651 commands like bootm or iminfo. This option is 652 automatically enabled when you select CFG_CMD_DATE . 653 654- Partition Support: 655 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 656 and/or CONFIG_ISO_PARTITION 657 658 If IDE or SCSI support is enabled (CFG_CMD_IDE or 659 CFG_CMD_SCSI) you must configure support for at least 660 one partition type as well. 661 662- IDE Reset method: 663 CONFIG_IDE_RESET_ROUTINE 664 665 Set this to define that instead of a reset Pin, the 666 routine ide_set_reset(int idereset) will be used. 667 668- ATAPI Support: 669 CONFIG_ATAPI 670 671 Set this to enable ATAPI support. 672 673- LBA48 Support 674 CONFIG_LBA48 675 676 Set this to enable support for disks larger than 137GB 677 Also look at CFG_64BIT_LBA ,CFG_64BIT_VSPRINTF and CFG_64BIT_STRTOUL 678 Whithout these , LBA48 support uses 32bit variables and will 'only' 679 support disks up to 2.1TB. 680 681 CFG_64BIT_LBA: 682 When enabled, makes the IDE subsystem use 64bit sector addresses. 683 Default is 32bit. 684 685- SCSI Support: 686 At the moment only there is only support for the 687 SYM53C8XX SCSI controller; define 688 CONFIG_SCSI_SYM53C8XX to enable it. 689 690 CFG_SCSI_MAX_LUN [8], CFG_SCSI_MAX_SCSI_ID [7] and 691 CFG_SCSI_MAX_DEVICE [CFG_SCSI_MAX_SCSI_ID * 692 CFG_SCSI_MAX_LUN] can be adjusted to define the 693 maximum numbers of LUNs, SCSI ID's and target 694 devices. 695 CFG_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 696 697- NETWORK Support (PCI): 698 CONFIG_E1000 699 Support for Intel 8254x gigabit chips. 700 701 CONFIG_EEPRO100 702 Support for Intel 82557/82559/82559ER chips. 703 Optional CONFIG_EEPRO100_SROM_WRITE enables eeprom 704 write routine for first time initialisation. 705 706 CONFIG_TULIP 707 Support for Digital 2114x chips. 708 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 709 modem chip initialisation (KS8761/QS6611). 710 711 CONFIG_NATSEMI 712 Support for National dp83815 chips. 713 714 CONFIG_NS8382X 715 Support for National dp8382[01] gigabit chips. 716 717- NETWORK Support (other): 718 719 CONFIG_DRIVER_LAN91C96 720 Support for SMSC's LAN91C96 chips. 721 722 CONFIG_LAN91C96_BASE 723 Define this to hold the physical address 724 of the LAN91C96's I/O space 725 726 CONFIG_LAN91C96_USE_32_BIT 727 Define this to enable 32 bit addressing 728 729- USB Support: 730 At the moment only the UHCI host controller is 731 supported (PIP405, MIP405); define 732 CONFIG_USB_UHCI to enable it. 733 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 734 end define CONFIG_USB_STORAGE to enable the USB 735 storage devices. 736 Note: 737 Supported are USB Keyboards and USB Floppy drives 738 (TEAC FD-05PUB). 739 740- MMC Support: 741 The MMC controller on the Intel PXA is supported. To 742 enable this define CONFIG_MMC. The MMC can be 743 accessed from the boot prompt by mapping the device 744 to physical memory similar to flash. Command line is 745 enabled with CFG_CMD_MMC. The MMC driver also works with 746 the FAT fs. This is enabled with CFG_CMD_FAT. 747 748- Keyboard Support: 749 CONFIG_ISA_KEYBOARD 750 751 Define this to enable standard (PC-Style) keyboard 752 support 753 754 CONFIG_I8042_KBD 755 Standard PC keyboard driver with US (is default) and 756 GERMAN key layout (switch via environment 'keymap=de') support. 757 Export function i8042_kbd_init, i8042_tstc and i8042_getc 758 for cfb_console. Supports cursor blinking. 759 760- Video support: 761 CONFIG_VIDEO 762 763 Define this to enable video support (for output to 764 video). 765 766 CONFIG_VIDEO_CT69000 767 768 Enable Chips & Technologies 69000 Video chip 769 770 CONFIG_VIDEO_SMI_LYNXEM 771 Enable Silicon Motion SMI 712/710/810 Video chip 772 Videomode are selected via environment 'videomode' with 773 standard LiLo mode numbers. 774 Following modes are supported (* is default): 775 776 800x600 1024x768 1280x1024 777 256 (8bit) 303* 305 307 778 65536 (16bit) 314 317 31a 779 16,7 Mill (24bit) 315 318 31b 780 (i.e. setenv videomode 317; saveenv; reset;) 781 782 CONFIG_VIDEO_SED13806 783 Enable Epson SED13806 driver. This driver supports 8bpp 784 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 785 or CONFIG_VIDEO_SED13806_16BPP 786 787- Keyboard Support: 788 CONFIG_KEYBOARD 789 790 Define this to enable a custom keyboard support. 791 This simply calls drv_keyboard_init() which must be 792 defined in your board-specific files. 793 The only board using this so far is RBC823. 794 795- LCD Support: CONFIG_LCD 796 797 Define this to enable LCD support (for output to LCD 798 display); also select one of the supported displays 799 by defining one of these: 800 801 CONFIG_NEC_NL6448AC33: 802 803 NEC NL6448AC33-18. Active, color, single scan. 804 805 CONFIG_NEC_NL6448BC20 806 807 NEC NL6448BC20-08. 6.5", 640x480. 808 Active, color, single scan. 809 810 CONFIG_NEC_NL6448BC33_54 811 812 NEC NL6448BC33-54. 10.4", 640x480. 813 Active, color, single scan. 814 815 CONFIG_SHARP_16x9 816 817 Sharp 320x240. Active, color, single scan. 818 It isn't 16x9, and I am not sure what it is. 819 820 CONFIG_SHARP_LQ64D341 821 822 Sharp LQ64D341 display, 640x480. 823 Active, color, single scan. 824 825 CONFIG_HLD1045 826 827 HLD1045 display, 640x480. 828 Active, color, single scan. 829 830 CONFIG_OPTREX_BW 831 832 Optrex CBL50840-2 NF-FW 99 22 M5 833 or 834 Hitachi LMG6912RPFC-00T 835 or 836 Hitachi SP14Q002 837 838 320x240. Black & white. 839 840 Normally display is black on white background; define 841 CFG_WHITE_ON_BLACK to get it inverted. 842 843- Splash Screen Support: CONFIG_SPLASH_SCREEN 844 845 If this option is set, the environment is checked for 846 a variable "splashimage". If found, the usual display 847 of logo, copyright and system information on the LCD 848 is supressed and the BMP image at the address 849 specified in "splashimage" is loaded instead. The 850 console is redirected to the "nulldev", too. This 851 allows for a "silent" boot where a splash screen is 852 loaded very quickly after power-on. 853 854- Compression support: 855 CONFIG_BZIP2 856 857 If this option is set, support for bzip2 compressed 858 images is included. If not, only uncompressed and gzip 859 compressed images are supported. 860 861 NOTE: the bzip2 algorithm requires a lot of RAM, so 862 the malloc area (as defined by CFG_MALLOC_LEN) should 863 be at least 4MB. 864 865- Ethernet address: 866 CONFIG_ETHADDR 867 CONFIG_ETH2ADDR 868 CONFIG_ETH3ADDR 869 870 Define a default value for ethernet address to use 871 for the respective ethernet interface, in case this 872 is not determined automatically. 873 874- IP address: 875 CONFIG_IPADDR 876 877 Define a default value for the IP address to use for 878 the default ethernet interface, in case this is not 879 determined through e.g. bootp. 880 881- Server IP address: 882 CONFIG_SERVERIP 883 884 Defines a default value for theIP address of a TFTP 885 server to contact when using the "tftboot" command. 886 887- BOOTP Recovery Mode: 888 CONFIG_BOOTP_RANDOM_DELAY 889 890 If you have many targets in a network that try to 891 boot using BOOTP, you may want to avoid that all 892 systems send out BOOTP requests at precisely the same 893 moment (which would happen for instance at recovery 894 from a power failure, when all systems will try to 895 boot, thus flooding the BOOTP server. Defining 896 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 897 inserted before sending out BOOTP requests. The 898 following delays are insterted then: 899 900 1st BOOTP request: delay 0 ... 1 sec 901 2nd BOOTP request: delay 0 ... 2 sec 902 3rd BOOTP request: delay 0 ... 4 sec 903 4th and following 904 BOOTP requests: delay 0 ... 8 sec 905 906- DHCP Advanced Options: 907 CONFIG_BOOTP_MASK 908 909 You can fine tune the DHCP functionality by adding 910 these flags to the CONFIG_BOOTP_MASK define: 911 912 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 913 serverip from a DHCP server, it is possible that more 914 than one DNS serverip is offered to the client. 915 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 916 serverip will be stored in the additional environment 917 variable "dnsip2". The first DNS serverip is always 918 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 919 is added to the CONFIG_BOOTP_MASK. 920 921 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 922 to do a dynamic update of a DNS server. To do this, they 923 need the hostname of the DHCP requester. 924 If CONFIG_BOOP_SEND_HOSTNAME is added to the 925 CONFIG_BOOTP_MASK, the content of the "hostname" 926 environment variable is passed as option 12 to 927 the DHCP server. 928 929- Status LED: CONFIG_STATUS_LED 930 931 Several configurations allow to display the current 932 status using a LED. For instance, the LED will blink 933 fast while running U-Boot code, stop blinking as 934 soon as a reply to a BOOTP request was received, and 935 start blinking slow once the Linux kernel is running 936 (supported by a status LED driver in the Linux 937 kernel). Defining CONFIG_STATUS_LED enables this 938 feature in U-Boot. 939 940- CAN Support: CONFIG_CAN_DRIVER 941 942 Defining CONFIG_CAN_DRIVER enables CAN driver support 943 on those systems that support this (optional) 944 feature, like the TQM8xxL modules. 945 946- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 947 948 These enable I2C serial bus commands. Defining either of 949 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 950 include the appropriate I2C driver for the selected cpu. 951 952 This will allow you to use i2c commands at the u-boot 953 command line (as long as you set CFG_CMD_I2C in 954 CONFIG_COMMANDS) and communicate with i2c based realtime 955 clock chips. See common/cmd_i2c.c for a description of the 956 command line interface. 957 958 CONFIG_HARD_I2C selects the CPM hardware driver for I2C. 959 960 CONFIG_SOFT_I2C configures u-boot to use a software (aka 961 bit-banging) driver instead of CPM or similar hardware 962 support for I2C. 963 964 There are several other quantities that must also be 965 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 966 967 In both cases you will need to define CFG_I2C_SPEED 968 to be the frequency (in Hz) at which you wish your i2c bus 969 to run and CFG_I2C_SLAVE to be the address of this node (ie 970 the cpu's i2c node address). 971 972 Now, the u-boot i2c code for the mpc8xx (cpu/mpc8xx/i2c.c) 973 sets the cpu up as a master node and so its address should 974 therefore be cleared to 0 (See, eg, MPC823e User's Manual 975 p.16-473). So, set CFG_I2C_SLAVE to 0. 976 977 That's all that's required for CONFIG_HARD_I2C. 978 979 If you use the software i2c interface (CONFIG_SOFT_I2C) 980 then the following macros need to be defined (examples are 981 from include/configs/lwmon.h): 982 983 I2C_INIT 984 985 (Optional). Any commands necessary to enable the I2C 986 controller or configure ports. 987 988 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 989 990 I2C_PORT 991 992 (Only for MPC8260 CPU). The I/O port to use (the code 993 assumes both bits are on the same port). Valid values 994 are 0..3 for ports A..D. 995 996 I2C_ACTIVE 997 998 The code necessary to make the I2C data line active 999 (driven). If the data line is open collector, this 1000 define can be null. 1001 1002 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1003 1004 I2C_TRISTATE 1005 1006 The code necessary to make the I2C data line tri-stated 1007 (inactive). If the data line is open collector, this 1008 define can be null. 1009 1010 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1011 1012 I2C_READ 1013 1014 Code that returns TRUE if the I2C data line is high, 1015 FALSE if it is low. 1016 1017 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1018 1019 I2C_SDA(bit) 1020 1021 If <bit> is TRUE, sets the I2C data line high. If it 1022 is FALSE, it clears it (low). 1023 1024 eg: #define I2C_SDA(bit) \ 1025 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1026 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1027 1028 I2C_SCL(bit) 1029 1030 If <bit> is TRUE, sets the I2C clock line high. If it 1031 is FALSE, it clears it (low). 1032 1033 eg: #define I2C_SCL(bit) \ 1034 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1035 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1036 1037 I2C_DELAY 1038 1039 This delay is invoked four times per clock cycle so this 1040 controls the rate of data transfer. The data rate thus 1041 is 1 / (I2C_DELAY * 4). Often defined to be something 1042 like: 1043 1044 #define I2C_DELAY udelay(2) 1045 1046 CFG_I2C_INIT_BOARD 1047 1048 When a board is reset during an i2c bus transfer 1049 chips might think that the current transfer is still 1050 in progress. On some boards it is possible to access 1051 the i2c SCLK line directly, either by using the 1052 processor pin as a GPIO or by having a second pin 1053 connected to the bus. If this option is defined a 1054 custom i2c_init_board() routine in boards/xxx/board.c 1055 is run early in the boot sequence. 1056 1057- SPI Support: CONFIG_SPI 1058 1059 Enables SPI driver (so far only tested with 1060 SPI EEPROM, also an instance works with Crystal A/D and 1061 D/As on the SACSng board) 1062 1063 CONFIG_SPI_X 1064 1065 Enables extended (16-bit) SPI EEPROM addressing. 1066 (symmetrical to CONFIG_I2C_X) 1067 1068 CONFIG_SOFT_SPI 1069 1070 Enables a software (bit-bang) SPI driver rather than 1071 using hardware support. This is a general purpose 1072 driver that only requires three general I/O port pins 1073 (two outputs, one input) to function. If this is 1074 defined, the board configuration must define several 1075 SPI configuration items (port pins to use, etc). For 1076 an example, see include/configs/sacsng.h. 1077 1078- FPGA Support: CONFIG_FPGA_COUNT 1079 1080 Specify the number of FPGA devices to support. 1081 1082 CONFIG_FPGA 1083 1084 Used to specify the types of FPGA devices. For example, 1085 #define CONFIG_FPGA CFG_XILINX_VIRTEX2 1086 1087 CFG_FPGA_PROG_FEEDBACK 1088 1089 Enable printing of hash marks during FPGA configuration. 1090 1091 CFG_FPGA_CHECK_BUSY 1092 1093 Enable checks on FPGA configuration interface busy 1094 status by the configuration function. This option 1095 will require a board or device specific function to 1096 be written. 1097 1098 CONFIG_FPGA_DELAY 1099 1100 If defined, a function that provides delays in the FPGA 1101 configuration driver. 1102 1103 CFG_FPGA_CHECK_CTRLC 1104 Allow Control-C to interrupt FPGA configuration 1105 1106 CFG_FPGA_CHECK_ERROR 1107 1108 Check for configuration errors during FPGA bitfile 1109 loading. For example, abort during Virtex II 1110 configuration if the INIT_B line goes low (which 1111 indicated a CRC error). 1112 1113 CFG_FPGA_WAIT_INIT 1114 1115 Maximum time to wait for the INIT_B line to deassert 1116 after PROB_B has been deasserted during a Virtex II 1117 FPGA configuration sequence. The default time is 500 1118 mS. 1119 1120 CFG_FPGA_WAIT_BUSY 1121 1122 Maximum time to wait for BUSY to deassert during 1123 Virtex II FPGA configuration. The default is 5 mS. 1124 1125 CFG_FPGA_WAIT_CONFIG 1126 1127 Time to wait after FPGA configuration. The default is 1128 200 mS. 1129 1130- Configuration Management: 1131 CONFIG_IDENT_STRING 1132 1133 If defined, this string will be added to the U-Boot 1134 version information (U_BOOT_VERSION) 1135 1136- Vendor Parameter Protection: 1137 1138 U-Boot considers the values of the environment 1139 variables "serial#" (Board Serial Number) and 1140 "ethaddr" (Ethernet Address) to be parameters that 1141 are set once by the board vendor / manufacturer, and 1142 protects these variables from casual modification by 1143 the user. Once set, these variables are read-only, 1144 and write or delete attempts are rejected. You can 1145 change this behviour: 1146 1147 If CONFIG_ENV_OVERWRITE is #defined in your config 1148 file, the write protection for vendor parameters is 1149 completely disabled. Anybody can change or delete 1150 these parameters. 1151 1152 Alternatively, if you #define _both_ CONFIG_ETHADDR 1153 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1154 ethernet address is installed in the environment, 1155 which can be changed exactly ONCE by the user. [The 1156 serial# is unaffected by this, i. e. it remains 1157 read-only.] 1158 1159- Protected RAM: 1160 CONFIG_PRAM 1161 1162 Define this variable to enable the reservation of 1163 "protected RAM", i. e. RAM which is not overwritten 1164 by U-Boot. Define CONFIG_PRAM to hold the number of 1165 kB you want to reserve for pRAM. You can overwrite 1166 this default value by defining an environment 1167 variable "pram" to the number of kB you want to 1168 reserve. Note that the board info structure will 1169 still show the full amount of RAM. If pRAM is 1170 reserved, a new environment variable "mem" will 1171 automatically be defined to hold the amount of 1172 remaining RAM in a form that can be passed as boot 1173 argument to Linux, for instance like that: 1174 1175 setenv bootargs ... mem=\$(mem) 1176 saveenv 1177 1178 This way you can tell Linux not to use this memory, 1179 either, which results in a memory region that will 1180 not be affected by reboots. 1181 1182 *WARNING* If your board configuration uses automatic 1183 detection of the RAM size, you must make sure that 1184 this memory test is non-destructive. So far, the 1185 following board configurations are known to be 1186 "pRAM-clean": 1187 1188 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1189 HERMES, IP860, RPXlite, LWMON, LANTEC, 1190 PCU_E, FLAGADM, TQM8260 1191 1192- Error Recovery: 1193 CONFIG_PANIC_HANG 1194 1195 Define this variable to stop the system in case of a 1196 fatal error, so that you have to reset it manually. 1197 This is probably NOT a good idea for an embedded 1198 system where you want to system to reboot 1199 automatically as fast as possible, but it may be 1200 useful during development since you can try to debug 1201 the conditions that lead to the situation. 1202 1203 CONFIG_NET_RETRY_COUNT 1204 1205 This variable defines the number of retries for 1206 network operations like ARP, RARP, TFTP, or BOOTP 1207 before giving up the operation. If not defined, a 1208 default value of 5 is used. 1209 1210- Command Interpreter: 1211 CFG_HUSH_PARSER 1212 1213 Define this variable to enable the "hush" shell (from 1214 Busybox) as command line interpreter, thus enabling 1215 powerful command line syntax like 1216 if...then...else...fi conditionals or `&&' and '||' 1217 constructs ("shell scripts"). 1218 1219 If undefined, you get the old, much simpler behaviour 1220 with a somewhat smaller memory footprint. 1221 1222 1223 CFG_PROMPT_HUSH_PS2 1224 1225 This defines the secondary prompt string, which is 1226 printed when the command interpreter needs more input 1227 to complete a command. Usually "> ". 1228 1229 Note: 1230 1231 In the current implementation, the local variables 1232 space and global environment variables space are 1233 separated. Local variables are those you define by 1234 simply typing `name=value'. To access a local 1235 variable later on, you have write `$name' or 1236 `${name}'; to execute the contents of a variable 1237 directly type `$name' at the command prompt. 1238 1239 Global environment variables are those you use 1240 setenv/printenv to work with. To run a command stored 1241 in such a variable, you need to use the run command, 1242 and you must not use the '$' sign to access them. 1243 1244 To store commands and special characters in a 1245 variable, please use double quotation marks 1246 surrounding the whole text of the variable, instead 1247 of the backslashes before semicolons and special 1248 symbols. 1249 1250- Default Environment: 1251 CONFIG_EXTRA_ENV_SETTINGS 1252 1253 Define this to contain any number of null terminated 1254 strings (variable = value pairs) that will be part of 1255 the default environment compiled into the boot image. 1256 1257 For example, place something like this in your 1258 board's config file: 1259 1260 #define CONFIG_EXTRA_ENV_SETTINGS \ 1261 "myvar1=value1\0" \ 1262 "myvar2=value2\0" 1263 1264 Warning: This method is based on knowledge about the 1265 internal format how the environment is stored by the 1266 U-Boot code. This is NOT an official, exported 1267 interface! Although it is unlikely that this format 1268 will change soon, there is no guarantee either. 1269 You better know what you are doing here. 1270 1271 Note: overly (ab)use of the default environment is 1272 discouraged. Make sure to check other ways to preset 1273 the environment like the autoscript function or the 1274 boot command first. 1275 1276- DataFlash Support: 1277 CONFIG_HAS_DATAFLASH 1278 1279 Defining this option enables DataFlash features and 1280 allows to read/write in Dataflash via the standard 1281 commands cp, md... 1282 1283- SystemACE Support: 1284 CONFIG_SYSTEMACE 1285 1286 Adding this option adds support for Xilinx SystemACE 1287 chips attached via some sort of local bus. The address 1288 of the chip must alsh be defined in the 1289 CFG_SYSTEMACE_BASE macro. For example: 1290 1291 #define CONFIG_SYSTEMACE 1292 #define CFG_SYSTEMACE_BASE 0xf0000000 1293 1294 When SystemACE support is added, the "ace" device type 1295 becomes available to the fat commands, i.e. fatls. 1296 1297- Show boot progress: 1298 CONFIG_SHOW_BOOT_PROGRESS 1299 1300 Defining this option allows to add some board- 1301 specific code (calling a user-provided function 1302 "show_boot_progress(int)") that enables you to show 1303 the system's boot progress on some display (for 1304 example, some LED's) on your board. At the moment, 1305 the following checkpoints are implemented: 1306 1307 Arg Where When 1308 1 common/cmd_bootm.c before attempting to boot an image 1309 -1 common/cmd_bootm.c Image header has bad magic number 1310 2 common/cmd_bootm.c Image header has correct magic number 1311 -2 common/cmd_bootm.c Image header has bad checksum 1312 3 common/cmd_bootm.c Image header has correct checksum 1313 -3 common/cmd_bootm.c Image data has bad checksum 1314 4 common/cmd_bootm.c Image data has correct checksum 1315 -4 common/cmd_bootm.c Image is for unsupported architecture 1316 5 common/cmd_bootm.c Architecture check OK 1317 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1318 6 common/cmd_bootm.c Image Type check OK 1319 -6 common/cmd_bootm.c gunzip uncompression error 1320 -7 common/cmd_bootm.c Unimplemented compression type 1321 7 common/cmd_bootm.c Uncompression OK 1322 -8 common/cmd_bootm.c Wrong Image Type (not kernel, multi, standalone) 1323 8 common/cmd_bootm.c Image Type check OK 1324 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 1325 9 common/cmd_bootm.c Start initial ramdisk verification 1326 -10 common/cmd_bootm.c Ramdisk header has bad magic number 1327 -11 common/cmd_bootm.c Ramdisk header has bad checksum 1328 10 common/cmd_bootm.c Ramdisk header is OK 1329 -12 common/cmd_bootm.c Ramdisk data has bad checksum 1330 11 common/cmd_bootm.c Ramdisk data has correct checksum 1331 12 common/cmd_bootm.c Ramdisk verification complete, start loading 1332 -13 common/cmd_bootm.c Wrong Image Type (not PPC Linux Ramdisk) 1333 13 common/cmd_bootm.c Start multifile image verification 1334 14 common/cmd_bootm.c No initial ramdisk, no multifile, continue. 1335 15 common/cmd_bootm.c All preparation done, transferring control to OS 1336 1337 -30 lib_ppc/board.c Fatal error, hang the system 1338 -31 post/post.c POST test failed, detected by post_output_backlog() 1339 -32 post/post.c POST test failed, detected by post_run_single() 1340 1341 -1 common/cmd_doc.c Bad usage of "doc" command 1342 -1 common/cmd_doc.c No boot device 1343 -1 common/cmd_doc.c Unknown Chip ID on boot device 1344 -1 common/cmd_doc.c Read Error on boot device 1345 -1 common/cmd_doc.c Image header has bad magic number 1346 1347 -1 common/cmd_ide.c Bad usage of "ide" command 1348 -1 common/cmd_ide.c No boot device 1349 -1 common/cmd_ide.c Unknown boot device 1350 -1 common/cmd_ide.c Unknown partition table 1351 -1 common/cmd_ide.c Invalid partition type 1352 -1 common/cmd_ide.c Read Error on boot device 1353 -1 common/cmd_ide.c Image header has bad magic number 1354 1355 -1 common/cmd_nand.c Bad usage of "nand" command 1356 -1 common/cmd_nand.c No boot device 1357 -1 common/cmd_nand.c Unknown Chip ID on boot device 1358 -1 common/cmd_nand.c Read Error on boot device 1359 -1 common/cmd_nand.c Image header has bad magic number 1360 1361 -1 common/env_common.c Environment has a bad CRC, using default 1362 1363 1364Modem Support: 1365-------------- 1366 1367[so far only for SMDK2400 and TRAB boards] 1368 1369- Modem support endable: 1370 CONFIG_MODEM_SUPPORT 1371 1372- RTS/CTS Flow control enable: 1373 CONFIG_HWFLOW 1374 1375- Modem debug support: 1376 CONFIG_MODEM_SUPPORT_DEBUG 1377 1378 Enables debugging stuff (char screen[1024], dbg()) 1379 for modem support. Useful only with BDI2000. 1380 1381- Interrupt support (PPC): 1382 1383 There are common interrupt_init() and timer_interrupt() 1384 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 1385 for cpu specific initialization. interrupt_init_cpu() 1386 should set decrementer_count to appropriate value. If 1387 cpu resets decrementer automatically after interrupt 1388 (ppc4xx) it should set decrementer_count to zero. 1389 timer_interrupt() calls timer_interrupt_cpu() for cpu 1390 specific handling. If board has watchdog / status_led 1391 / other_activity_monitor it works automatically from 1392 general timer_interrupt(). 1393 1394- General: 1395 1396 In the target system modem support is enabled when a 1397 specific key (key combination) is pressed during 1398 power-on. Otherwise U-Boot will boot normally 1399 (autoboot). The key_pressed() fuction is called from 1400 board_init(). Currently key_pressed() is a dummy 1401 function, returning 1 and thus enabling modem 1402 initialization. 1403 1404 If there are no modem init strings in the 1405 environment, U-Boot proceed to autoboot; the 1406 previous output (banner, info printfs) will be 1407 supressed, though. 1408 1409 See also: doc/README.Modem 1410 1411 1412Configuration Settings: 1413----------------------- 1414 1415- CFG_LONGHELP: Defined when you want long help messages included; 1416 undefine this when you're short of memory. 1417 1418- CFG_PROMPT: This is what U-Boot prints on the console to 1419 prompt for user input. 1420 1421- CFG_CBSIZE: Buffer size for input from the Console 1422 1423- CFG_PBSIZE: Buffer size for Console output 1424 1425- CFG_MAXARGS: max. Number of arguments accepted for monitor commands 1426 1427- CFG_BARGSIZE: Buffer size for Boot Arguments which are passed to 1428 the application (usually a Linux kernel) when it is 1429 booted 1430 1431- CFG_BAUDRATE_TABLE: 1432 List of legal baudrate settings for this board. 1433 1434- CFG_CONSOLE_INFO_QUIET 1435 Suppress display of console information at boot. 1436 1437- CFG_CONSOLE_IS_IN_ENV 1438 If the board specific function 1439 extern int overwrite_console (void); 1440 returns 1, the stdin, stderr and stdout are switched to the 1441 serial port, else the settings in the environment are used. 1442 1443- CFG_CONSOLE_OVERWRITE_ROUTINE 1444 Enable the call to overwrite_console(). 1445 1446- CFG_CONSOLE_ENV_OVERWRITE 1447 Enable overwrite of previous console environment settings. 1448 1449- CFG_MEMTEST_START, CFG_MEMTEST_END: 1450 Begin and End addresses of the area used by the 1451 simple memory test. 1452 1453- CFG_ALT_MEMTEST: 1454 Enable an alternate, more extensive memory test. 1455 1456- CFG_MEMTEST_SCRATCH: 1457 Scratch address used by the alternate memory test 1458 You only need to set this if address zero isn't writeable 1459 1460- CFG_TFTP_LOADADDR: 1461 Default load address for network file downloads 1462 1463- CFG_LOADS_BAUD_CHANGE: 1464 Enable temporary baudrate change while serial download 1465 1466- CFG_SDRAM_BASE: 1467 Physical start address of SDRAM. _Must_ be 0 here. 1468 1469- CFG_MBIO_BASE: 1470 Physical start address of Motherboard I/O (if using a 1471 Cogent motherboard) 1472 1473- CFG_FLASH_BASE: 1474 Physical start address of Flash memory. 1475 1476- CFG_MONITOR_BASE: 1477 Physical start address of boot monitor code (set by 1478 make config files to be same as the text base address 1479 (TEXT_BASE) used when linking) - same as 1480 CFG_FLASH_BASE when booting from flash. 1481 1482- CFG_MONITOR_LEN: 1483 Size of memory reserved for monitor code, used to 1484 determine _at_compile_time_ (!) if the environment is 1485 embedded within the U-Boot image, or in a separate 1486 flash sector. 1487 1488- CFG_MALLOC_LEN: 1489 Size of DRAM reserved for malloc() use. 1490 1491- CFG_BOOTMAPSZ: 1492 Maximum size of memory mapped by the startup code of 1493 the Linux kernel; all data that must be processed by 1494 the Linux kernel (bd_info, boot arguments, eventually 1495 initrd image) must be put below this limit. 1496 1497- CFG_MAX_FLASH_BANKS: 1498 Max number of Flash memory banks 1499 1500- CFG_MAX_FLASH_SECT: 1501 Max number of sectors on a Flash chip 1502 1503- CFG_FLASH_ERASE_TOUT: 1504 Timeout for Flash erase operations (in ms) 1505 1506- CFG_FLASH_WRITE_TOUT: 1507 Timeout for Flash write operations (in ms) 1508 1509- CFG_FLASH_LOCK_TOUT 1510 Timeout for Flash set sector lock bit operation (in ms) 1511 1512- CFG_FLASH_UNLOCK_TOUT 1513 Timeout for Flash clear lock bits operation (in ms) 1514 1515- CFG_FLASH_PROTECTION 1516 If defined, hardware flash sectors protection is used 1517 instead of U-Boot software protection. 1518 1519- CFG_DIRECT_FLASH_TFTP: 1520 1521 Enable TFTP transfers directly to flash memory; 1522 without this option such a download has to be 1523 performed in two steps: (1) download to RAM, and (2) 1524 copy from RAM to flash. 1525 1526 The two-step approach is usually more reliable, since 1527 you can check if the download worked before you erase 1528 the flash, but in some situations (when sytem RAM is 1529 too limited to allow for a tempory copy of the 1530 downloaded image) this option may be very useful. 1531 1532- CFG_FLASH_CFI: 1533 Define if the flash driver uses extra elements in the 1534 common flash structure for storing flash geometry. 1535 1536- CFG_FLASH_CFI_DRIVER 1537 This option also enables the building of the cfi_flash driver 1538 in the drivers directory 1539 1540- CFG_RX_ETH_BUFFER: 1541 Defines the number of ethernet receive buffers. On some 1542 ethernet controllers it is recommended to set this value 1543 to 8 or even higher (EEPRO100 or 405 EMAC), since all 1544 buffers can be full shortly after enabling the interface 1545 on high ethernet traffic. 1546 Defaults to 4 if not defined. 1547 1548The following definitions that deal with the placement and management 1549of environment data (variable area); in general, we support the 1550following configurations: 1551 1552- CFG_ENV_IS_IN_FLASH: 1553 1554 Define this if the environment is in flash memory. 1555 1556 a) The environment occupies one whole flash sector, which is 1557 "embedded" in the text segment with the U-Boot code. This 1558 happens usually with "bottom boot sector" or "top boot 1559 sector" type flash chips, which have several smaller 1560 sectors at the start or the end. For instance, such a 1561 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 1562 such a case you would place the environment in one of the 1563 4 kB sectors - with U-Boot code before and after it. With 1564 "top boot sector" type flash chips, you would put the 1565 environment in one of the last sectors, leaving a gap 1566 between U-Boot and the environment. 1567 1568 - CFG_ENV_OFFSET: 1569 1570 Offset of environment data (variable area) to the 1571 beginning of flash memory; for instance, with bottom boot 1572 type flash chips the second sector can be used: the offset 1573 for this sector is given here. 1574 1575 CFG_ENV_OFFSET is used relative to CFG_FLASH_BASE. 1576 1577 - CFG_ENV_ADDR: 1578 1579 This is just another way to specify the start address of 1580 the flash sector containing the environment (instead of 1581 CFG_ENV_OFFSET). 1582 1583 - CFG_ENV_SECT_SIZE: 1584 1585 Size of the sector containing the environment. 1586 1587 1588 b) Sometimes flash chips have few, equal sized, BIG sectors. 1589 In such a case you don't want to spend a whole sector for 1590 the environment. 1591 1592 - CFG_ENV_SIZE: 1593 1594 If you use this in combination with CFG_ENV_IS_IN_FLASH 1595 and CFG_ENV_SECT_SIZE, you can specify to use only a part 1596 of this flash sector for the environment. This saves 1597 memory for the RAM copy of the environment. 1598 1599 It may also save flash memory if you decide to use this 1600 when your environment is "embedded" within U-Boot code, 1601 since then the remainder of the flash sector could be used 1602 for U-Boot code. It should be pointed out that this is 1603 STRONGLY DISCOURAGED from a robustness point of view: 1604 updating the environment in flash makes it always 1605 necessary to erase the WHOLE sector. If something goes 1606 wrong before the contents has been restored from a copy in 1607 RAM, your target system will be dead. 1608 1609 - CFG_ENV_ADDR_REDUND 1610 CFG_ENV_SIZE_REDUND 1611 1612 These settings describe a second storage area used to hold 1613 a redundand copy of the environment data, so that there is 1614 a valid backup copy in case there is a power failure during 1615 a "saveenv" operation. 1616 1617BE CAREFUL! Any changes to the flash layout, and some changes to the 1618source code will make it necessary to adapt <board>/u-boot.lds* 1619accordingly! 1620 1621 1622- CFG_ENV_IS_IN_NVRAM: 1623 1624 Define this if you have some non-volatile memory device 1625 (NVRAM, battery buffered SRAM) which you want to use for the 1626 environment. 1627 1628 - CFG_ENV_ADDR: 1629 - CFG_ENV_SIZE: 1630 1631 These two #defines are used to determin the memory area you 1632 want to use for environment. It is assumed that this memory 1633 can just be read and written to, without any special 1634 provision. 1635 1636BE CAREFUL! The first access to the environment happens quite early 1637in U-Boot initalization (when we try to get the setting of for the 1638console baudrate). You *MUST* have mappend your NVRAM area then, or 1639U-Boot will hang. 1640 1641Please note that even with NVRAM we still use a copy of the 1642environment in RAM: we could work on NVRAM directly, but we want to 1643keep settings there always unmodified except somebody uses "saveenv" 1644to save the current settings. 1645 1646 1647- CFG_ENV_IS_IN_EEPROM: 1648 1649 Use this if you have an EEPROM or similar serial access 1650 device and a driver for it. 1651 1652 - CFG_ENV_OFFSET: 1653 - CFG_ENV_SIZE: 1654 1655 These two #defines specify the offset and size of the 1656 environment area within the total memory of your EEPROM. 1657 1658 - CFG_I2C_EEPROM_ADDR: 1659 If defined, specified the chip address of the EEPROM device. 1660 The default address is zero. 1661 1662 - CFG_EEPROM_PAGE_WRITE_BITS: 1663 If defined, the number of bits used to address bytes in a 1664 single page in the EEPROM device. A 64 byte page, for example 1665 would require six bits. 1666 1667 - CFG_EEPROM_PAGE_WRITE_DELAY_MS: 1668 If defined, the number of milliseconds to delay between 1669 page writes. The default is zero milliseconds. 1670 1671 - CFG_I2C_EEPROM_ADDR_LEN: 1672 The length in bytes of the EEPROM memory array address. Note 1673 that this is NOT the chip address length! 1674 1675 - CFG_EEPROM_SIZE: 1676 The size in bytes of the EEPROM device. 1677 1678 1679- CFG_ENV_IS_IN_DATAFLASH: 1680 1681 Define this if you have a DataFlash memory device which you 1682 want to use for the environment. 1683 1684 - CFG_ENV_OFFSET: 1685 - CFG_ENV_ADDR: 1686 - CFG_ENV_SIZE: 1687 1688 These three #defines specify the offset and size of the 1689 environment area within the total memory of your DataFlash placed 1690 at the specified address. 1691 1692 1693- CFG_SPI_INIT_OFFSET 1694 1695 Defines offset to the initial SPI buffer area in DPRAM. The 1696 area is used at an early stage (ROM part) if the environment 1697 is configured to reside in the SPI EEPROM: We need a 520 byte 1698 scratch DPRAM area. It is used between the two initialization 1699 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 1700 to be a good choice since it makes it far enough from the 1701 start of the data area as well as from the stack pointer. 1702 1703Please note that the environment is read-only as long as the monitor 1704has been relocated to RAM and a RAM copy of the environment has been 1705created; also, when using EEPROM you will have to use getenv_r() 1706until then to read environment variables. 1707 1708The environment is protected by a CRC32 checksum. Before the monitor 1709is relocated into RAM, as a result of a bad CRC you will be working 1710with the compiled-in default environment - *silently*!!! [This is 1711necessary, because the first environment variable we need is the 1712"baudrate" setting for the console - if we have a bad CRC, we don't 1713have any device yet where we could complain.] 1714 1715Note: once the monitor has been relocated, then it will complain if 1716the default environment is used; a new CRC is computed as soon as you 1717use the "saveenv" command to store a valid environment. 1718 1719- CFG_FAULT_ECHO_LINK_DOWN: 1720 Echo the inverted Ethernet link state to the fault LED. 1721 1722 Note: If this option is active, then CFG_FAULT_MII_ADDR 1723 also needs to be defined. 1724 1725- CFG_FAULT_MII_ADDR: 1726 MII address of the PHY to check for the Ethernet link state. 1727 1728- CFG_64BIT_VSPRINTF: 1729 Makes vsprintf (and all *printf functions) support printing 1730 of 64bit values by using the L quantifier 1731 1732- CFG_64BIT_STRTOUL: 1733 Adds simple_strtoull that returns a 64bit value 1734 1735Low Level (hardware related) configuration options: 1736--------------------------------------------------- 1737 1738- CFG_CACHELINE_SIZE: 1739 Cache Line Size of the CPU. 1740 1741- CFG_DEFAULT_IMMR: 1742 Default address of the IMMR after system reset. 1743 1744 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 1745 and RPXsuper) to be able to adjust the position of 1746 the IMMR register after a reset. 1747 1748- Floppy Disk Support: 1749 CFG_FDC_DRIVE_NUMBER 1750 1751 the default drive number (default value 0) 1752 1753 CFG_ISA_IO_STRIDE 1754 1755 defines the spacing between fdc chipset registers 1756 (default value 1) 1757 1758 CFG_ISA_IO_OFFSET 1759 1760 defines the offset of register from address. It 1761 depends on which part of the data bus is connected to 1762 the fdc chipset. (default value 0) 1763 1764 If CFG_ISA_IO_STRIDE CFG_ISA_IO_OFFSET and 1765 CFG_FDC_DRIVE_NUMBER are undefined, they take their 1766 default value. 1767 1768 if CFG_FDC_HW_INIT is defined, then the function 1769 fdc_hw_init() is called at the beginning of the FDC 1770 setup. fdc_hw_init() must be provided by the board 1771 source code. It is used to make hardware dependant 1772 initializations. 1773 1774- CFG_IMMR: Physical address of the Internal Memory Mapped 1775 Register; DO NOT CHANGE! (11-4) 1776 [MPC8xx systems only] 1777 1778- CFG_INIT_RAM_ADDR: 1779 1780 Start address of memory area that can be used for 1781 initial data and stack; please note that this must be 1782 writable memory that is working WITHOUT special 1783 initialization, i. e. you CANNOT use normal RAM which 1784 will become available only after programming the 1785 memory controller and running certain initialization 1786 sequences. 1787 1788 U-Boot uses the following memory types: 1789 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 1790 - MPC824X: data cache 1791 - PPC4xx: data cache 1792 1793- CFG_GBL_DATA_OFFSET: 1794 1795 Offset of the initial data structure in the memory 1796 area defined by CFG_INIT_RAM_ADDR. Usually 1797 CFG_GBL_DATA_OFFSET is chosen such that the initial 1798 data is located at the end of the available space 1799 (sometimes written as (CFG_INIT_RAM_END - 1800 CFG_INIT_DATA_SIZE), and the initial stack is just 1801 below that area (growing from (CFG_INIT_RAM_ADDR + 1802 CFG_GBL_DATA_OFFSET) downward. 1803 1804 Note: 1805 On the MPC824X (or other systems that use the data 1806 cache for initial memory) the address chosen for 1807 CFG_INIT_RAM_ADDR is basically arbitrary - it must 1808 point to an otherwise UNUSED address space between 1809 the top of RAM and the start of the PCI space. 1810 1811- CFG_SIUMCR: SIU Module Configuration (11-6) 1812 1813- CFG_SYPCR: System Protection Control (11-9) 1814 1815- CFG_TBSCR: Time Base Status and Control (11-26) 1816 1817- CFG_PISCR: Periodic Interrupt Status and Control (11-31) 1818 1819- CFG_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 1820 1821- CFG_SCCR: System Clock and reset Control Register (15-27) 1822 1823- CFG_OR_TIMING_SDRAM: 1824 SDRAM timing 1825 1826- CFG_MAMR_PTA: 1827 periodic timer for refresh 1828 1829- CFG_DER: Debug Event Register (37-47) 1830 1831- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CFG_REMAP_OR_AM, 1832 CFG_PRELIM_OR_AM, CFG_OR_TIMING_FLASH, CFG_OR0_REMAP, 1833 CFG_OR0_PRELIM, CFG_BR0_PRELIM, CFG_OR1_REMAP, CFG_OR1_PRELIM, 1834 CFG_BR1_PRELIM: 1835 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 1836 1837- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 1838 CFG_OR_TIMING_SDRAM, CFG_OR2_PRELIM, CFG_BR2_PRELIM, 1839 CFG_OR3_PRELIM, CFG_BR3_PRELIM: 1840 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 1841 1842- CFG_MAMR_PTA, CFG_MPTPR_2BK_4K, CFG_MPTPR_1BK_4K, CFG_MPTPR_2BK_8K, 1843 CFG_MPTPR_1BK_8K, CFG_MAMR_8COL, CFG_MAMR_9COL: 1844 Machine Mode Register and Memory Periodic Timer 1845 Prescaler definitions (SDRAM timing) 1846 1847- CFG_I2C_UCODE_PATCH, CFG_I2C_DPMEM_OFFSET [0x1FC0]: 1848 enable I2C microcode relocation patch (MPC8xx); 1849 define relocation offset in DPRAM [DSP2] 1850 1851- CFG_SPI_UCODE_PATCH, CFG_SPI_DPMEM_OFFSET [0x1FC0]: 1852 enable SPI microcode relocation patch (MPC8xx); 1853 define relocation offset in DPRAM [SCC4] 1854 1855- CFG_USE_OSCCLK: 1856 Use OSCM clock mode on MBX8xx board. Be careful, 1857 wrong setting might damage your board. Read 1858 doc/README.MBX before setting this variable! 1859 1860- CFG_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 1861 Offset of the bootmode word in DPRAM used by post 1862 (Power On Self Tests). This definition overrides 1863 #define'd default value in commproc.h resp. 1864 cpm_8260.h. 1865 1866- CFG_PCI_SLV_MEM_LOCAL, CFG_PCI_SLV_MEM_BUS, CFG_PICMR0_MASK_ATTRIB, 1867 CFG_PCI_MSTR0_LOCAL, CFG_PCIMSK0_MASK, CFG_PCI_MSTR1_LOCAL, 1868 CFG_PCIMSK1_MASK, CFG_PCI_MSTR_MEM_LOCAL, CFG_PCI_MSTR_MEM_BUS, 1869 CFG_CPU_PCI_MEM_START, CFG_PCI_MSTR_MEM_SIZE, CFG_POCMR0_MASK_ATTRIB, 1870 CFG_PCI_MSTR_MEMIO_LOCAL, CFG_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 1871 CFG_PCI_MSTR_MEMIO_SIZE, CFG_POCMR1_MASK_ATTRIB, CFG_PCI_MSTR_IO_LOCAL, 1872 CFG_PCI_MSTR_IO_BUS, CFG_CPU_PCI_IO_START, CFG_PCI_MSTR_IO_SIZE, 1873 CFG_POCMR2_MASK_ATTRIB: (MPC826x only) 1874 Overrides the default PCI memory map in cpu/mpc8260/pci.c if set. 1875 1876Building the Software: 1877====================== 1878 1879Building U-Boot has been tested in native PPC environments (on a 1880PowerBook G3 running LinuxPPC 2000) and in cross environments 1881(running RedHat 6.x and 7.x Linux on x86, Solaris 2.6 on a SPARC, and 1882NetBSD 1.5 on x86). 1883 1884If you are not using a native PPC environment, it is assumed that you 1885have the GNU cross compiling tools available in your path and named 1886with a prefix of "powerpc-linux-". If this is not the case, (e.g. if 1887you are using Monta Vista's Hard Hat Linux CDK 1.2) you must change 1888the definition of CROSS_COMPILE in Makefile. For HHL on a 4xx CPU, 1889change it to: 1890 1891 CROSS_COMPILE = ppc_4xx- 1892 1893 1894U-Boot is intended to be simple to build. After installing the 1895sources you must configure U-Boot for one specific board type. This 1896is done by typing: 1897 1898 make NAME_config 1899 1900where "NAME_config" is the name of one of the existing 1901configurations; the following names are supported: 1902 1903 ADCIOP_config GTH_config TQM850L_config 1904 ADS860_config IP860_config TQM855L_config 1905 AR405_config IVML24_config TQM860L_config 1906 CANBT_config IVMS8_config WALNUT405_config 1907 CPCI405_config LANTEC_config cogent_common_config 1908 CPCIISER4_config MBX_config cogent_mpc8260_config 1909 CU824_config MBX860T_config cogent_mpc8xx_config 1910 ESTEEM192E_config RPXlite_config hermes_config 1911 ETX094_config RPXsuper_config hymod_config 1912 FADS823_config SM850_config lwmon_config 1913 FADS850SAR_config SPD823TS_config pcu_e_config 1914 FADS860T_config SXNI855T_config rsdproto_config 1915 FPS850L_config Sandpoint8240_config sbc8260_config 1916 GENIETV_config TQM823L_config PIP405_config 1917 GEN860T_config EBONY_config FPS860L_config 1918 ELPT860_config cmi_mpc5xx_config NETVIA_config 1919 at91rm9200dk_config omap1510inn_config MPC8260ADS_config 1920 omap1610inn_config ZPC1900_config MPC8540ADS_config 1921 MPC8560ADS_config QS850_config QS823_config 1922 QS860T_config DUET_ADS_config omap1610h2_config 1923 1924Note: for some board special configuration names may exist; check if 1925 additional information is available from the board vendor; for 1926 instance, the TQM8xxL systems run normally at 50 MHz and use a 1927 SCC for 10baseT ethernet; there are also systems with 80 MHz 1928 CPU clock, and an optional Fast Ethernet module is available 1929 for CPU's with FEC. You can select such additional "features" 1930 when chosing the configuration, i. e. 1931 1932 make TQM860L_config 1933 - will configure for a plain TQM860L, i. e. 50MHz, no FEC 1934 1935 make TQM860L_FEC_config 1936 - will configure for a TQM860L at 50MHz with FEC for ethernet 1937 1938 make TQM860L_80MHz_config 1939 - will configure for a TQM860L at 80 MHz, with normal 10baseT 1940 interface 1941 1942 make TQM860L_FEC_80MHz_config 1943 - will configure for a TQM860L at 80 MHz with FEC for ethernet 1944 1945 make TQM823L_LCD_config 1946 - will configure for a TQM823L with U-Boot console on LCD 1947 1948 make TQM823L_LCD_80MHz_config 1949 - will configure for a TQM823L at 80 MHz with U-Boot console on LCD 1950 1951 etc. 1952 1953 1954Finally, type "make all", and you should get some working U-Boot 1955images ready for download to / installation on your system: 1956 1957- "u-boot.bin" is a raw binary image 1958- "u-boot" is an image in ELF binary format 1959- "u-boot.srec" is in Motorola S-Record format 1960 1961 1962Please be aware that the Makefiles assume you are using GNU make, so 1963for instance on NetBSD you might need to use "gmake" instead of 1964native "make". 1965 1966 1967If the system board that you have is not listed, then you will need 1968to port U-Boot to your hardware platform. To do this, follow these 1969steps: 1970 19711. Add a new configuration option for your board to the toplevel 1972 "Makefile" and to the "MAKEALL" script, using the existing 1973 entries as examples. Note that here and at many other places 1974 boards and other names are listed in alphabetical sort order. Please 1975 keep this order. 19762. Create a new directory to hold your board specific code. Add any 1977 files you need. In your board directory, you will need at least 1978 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 19793. Create a new configuration file "include/configs/<board>.h" for 1980 your board 19813. If you're porting U-Boot to a new CPU, then also create a new 1982 directory to hold your CPU specific code. Add any files you need. 19834. Run "make <board>_config" with your new name. 19845. Type "make", and you should get a working "u-boot.srec" file 1985 to be installed on your target system. 19866. Debug and solve any problems that might arise. 1987 [Of course, this last step is much harder than it sounds.] 1988 1989 1990Testing of U-Boot Modifications, Ports to New Hardware, etc.: 1991============================================================== 1992 1993If you have modified U-Boot sources (for instance added a new board 1994or support for new devices, a new CPU, etc.) you are expected to 1995provide feedback to the other developers. The feedback normally takes 1996the form of a "patch", i. e. a context diff against a certain (latest 1997official or latest in CVS) version of U-Boot sources. 1998 1999But before you submit such a patch, please verify that your modifi- 2000cation did not break existing code. At least make sure that *ALL* of 2001the supported boards compile WITHOUT ANY compiler warnings. To do so, 2002just run the "MAKEALL" script, which will configure and build U-Boot 2003for ALL supported system. Be warned, this will take a while. You can 2004select which (cross) compiler to use by passing a `CROSS_COMPILE' 2005environment variable to the script, i. e. to use the cross tools from 2006MontaVista's Hard Hat Linux you can type 2007 2008 CROSS_COMPILE=ppc_8xx- MAKEALL 2009 2010or to build on a native PowerPC system you can type 2011 2012 CROSS_COMPILE=' ' MAKEALL 2013 2014See also "U-Boot Porting Guide" below. 2015 2016 2017Monitor Commands - Overview: 2018============================ 2019 2020go - start application at address 'addr' 2021run - run commands in an environment variable 2022bootm - boot application image from memory 2023bootp - boot image via network using BootP/TFTP protocol 2024tftpboot- boot image via network using TFTP protocol 2025 and env variables "ipaddr" and "serverip" 2026 (and eventually "gatewayip") 2027rarpboot- boot image via network using RARP/TFTP protocol 2028diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 2029loads - load S-Record file over serial line 2030loadb - load binary file over serial line (kermit mode) 2031md - memory display 2032mm - memory modify (auto-incrementing) 2033nm - memory modify (constant address) 2034mw - memory write (fill) 2035cp - memory copy 2036cmp - memory compare 2037crc32 - checksum calculation 2038imd - i2c memory display 2039imm - i2c memory modify (auto-incrementing) 2040inm - i2c memory modify (constant address) 2041imw - i2c memory write (fill) 2042icrc32 - i2c checksum calculation 2043iprobe - probe to discover valid I2C chip addresses 2044iloop - infinite loop on address range 2045isdram - print SDRAM configuration information 2046sspi - SPI utility commands 2047base - print or set address offset 2048printenv- print environment variables 2049setenv - set environment variables 2050saveenv - save environment variables to persistent storage 2051protect - enable or disable FLASH write protection 2052erase - erase FLASH memory 2053flinfo - print FLASH memory information 2054bdinfo - print Board Info structure 2055iminfo - print header information for application image 2056coninfo - print console devices and informations 2057ide - IDE sub-system 2058loop - infinite loop on address range 2059mtest - simple RAM test 2060icache - enable or disable instruction cache 2061dcache - enable or disable data cache 2062reset - Perform RESET of the CPU 2063echo - echo args to console 2064version - print monitor version 2065help - print online help 2066? - alias for 'help' 2067 2068 2069Monitor Commands - Detailed Description: 2070======================================== 2071 2072TODO. 2073 2074For now: just type "help <command>". 2075 2076 2077Environment Variables: 2078====================== 2079 2080U-Boot supports user configuration using Environment Variables which 2081can be made persistent by saving to Flash memory. 2082 2083Environment Variables are set using "setenv", printed using 2084"printenv", and saved to Flash using "saveenv". Using "setenv" 2085without a value can be used to delete a variable from the 2086environment. As long as you don't save the environment you are 2087working with an in-memory copy. In case the Flash area containing the 2088environment is erased by accident, a default environment is provided. 2089 2090Some configuration options can be set using Environment Variables: 2091 2092 baudrate - see CONFIG_BAUDRATE 2093 2094 bootdelay - see CONFIG_BOOTDELAY 2095 2096 bootcmd - see CONFIG_BOOTCOMMAND 2097 2098 bootargs - Boot arguments when booting an RTOS image 2099 2100 bootfile - Name of the image to load with TFTP 2101 2102 autoload - if set to "no" (any string beginning with 'n'), 2103 "bootp" will just load perform a lookup of the 2104 configuration from the BOOTP server, but not try to 2105 load any image using TFTP 2106 2107 autostart - if set to "yes", an image loaded using the "bootp", 2108 "rarpboot", "tftpboot" or "diskboot" commands will 2109 be automatically started (by internally calling 2110 "bootm") 2111 2112 If set to "no", a standalone image passed to the 2113 "bootm" command will be copied to the load address 2114 (and eventually uncompressed), but NOT be started. 2115 This can be used to load and uncompress arbitrary 2116 data. 2117 2118 initrd_high - restrict positioning of initrd images: 2119 If this variable is not set, initrd images will be 2120 copied to the highest possible address in RAM; this 2121 is usually what you want since it allows for 2122 maximum initrd size. If for some reason you want to 2123 make sure that the initrd image is loaded below the 2124 CFG_BOOTMAPSZ limit, you can set this environment 2125 variable to a value of "no" or "off" or "0". 2126 Alternatively, you can set it to a maximum upper 2127 address to use (U-Boot will still check that it 2128 does not overwrite the U-Boot stack and data). 2129 2130 For instance, when you have a system with 16 MB 2131 RAM, and want to reserve 4 MB from use by Linux, 2132 you can do this by adding "mem=12M" to the value of 2133 the "bootargs" variable. However, now you must make 2134 sure that the initrd image is placed in the first 2135 12 MB as well - this can be done with 2136 2137 setenv initrd_high 00c00000 2138 2139 If you set initrd_high to 0xFFFFFFFF, this is an 2140 indication to U-Boot that all addresses are legal 2141 for the Linux kernel, including addresses in flash 2142 memory. In this case U-Boot will NOT COPY the 2143 ramdisk at all. This may be useful to reduce the 2144 boot time on your system, but requires that this 2145 feature is supported by your Linux kernel. 2146 2147 ipaddr - IP address; needed for tftpboot command 2148 2149 loadaddr - Default load address for commands like "bootp", 2150 "rarpboot", "tftpboot", "loadb" or "diskboot" 2151 2152 loads_echo - see CONFIG_LOADS_ECHO 2153 2154 serverip - TFTP server IP address; needed for tftpboot command 2155 2156 bootretry - see CONFIG_BOOT_RETRY_TIME 2157 2158 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 2159 2160 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 2161 2162 2163The following environment variables may be used and automatically 2164updated by the network boot commands ("bootp" and "rarpboot"), 2165depending the information provided by your boot server: 2166 2167 bootfile - see above 2168 dnsip - IP address of your Domain Name Server 2169 dnsip2 - IP address of your secondary Domain Name Server 2170 gatewayip - IP address of the Gateway (Router) to use 2171 hostname - Target hostname 2172 ipaddr - see above 2173 netmask - Subnet Mask 2174 rootpath - Pathname of the root filesystem on the NFS server 2175 serverip - see above 2176 2177 2178There are two special Environment Variables: 2179 2180 serial# - contains hardware identification information such 2181 as type string and/or serial number 2182 ethaddr - Ethernet address 2183 2184These variables can be set only once (usually during manufacturing of 2185the board). U-Boot refuses to delete or overwrite these variables 2186once they have been set once. 2187 2188 2189Further special Environment Variables: 2190 2191 ver - Contains the U-Boot version string as printed 2192 with the "version" command. This variable is 2193 readonly (see CONFIG_VERSION_VARIABLE). 2194 2195 2196Please note that changes to some configuration parameters may take 2197only effect after the next boot (yes, that's just like Windoze :-). 2198 2199 2200Command Line Parsing: 2201===================== 2202 2203There are two different command line parsers available with U-Boot: 2204the old "simple" one, and the much more powerful "hush" shell: 2205 2206Old, simple command line parser: 2207-------------------------------- 2208 2209- supports environment variables (through setenv / saveenv commands) 2210- several commands on one line, separated by ';' 2211- variable substitution using "... $(name) ..." syntax 2212- special characters ('$', ';') can be escaped by prefixing with '\', 2213 for example: 2214 setenv bootcmd bootm \$(address) 2215- You can also escape text by enclosing in single apostrophes, for example: 2216 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 2217 2218Hush shell: 2219----------- 2220 2221- similar to Bourne shell, with control structures like 2222 if...then...else...fi, for...do...done; while...do...done, 2223 until...do...done, ... 2224- supports environment ("global") variables (through setenv / saveenv 2225 commands) and local shell variables (through standard shell syntax 2226 "name=value"); only environment variables can be used with "run" 2227 command 2228 2229General rules: 2230-------------- 2231 2232(1) If a command line (or an environment variable executed by a "run" 2233 command) contains several commands separated by semicolon, and 2234 one of these commands fails, then the remaining commands will be 2235 executed anyway. 2236 2237(2) If you execute several variables with one call to run (i. e. 2238 calling run with a list af variables as arguments), any failing 2239 command will cause "run" to terminate, i. e. the remaining 2240 variables are not executed. 2241 2242Note for Redundant Ethernet Interfaces: 2243======================================= 2244 2245Some boards come with redundant ethernet interfaces; U-Boot supports 2246such configurations and is capable of automatic selection of a 2247"working" interface when needed. MAC assignment works as follows: 2248 2249Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 2250MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 2251"eth1addr" (=>eth1), "eth2addr", ... 2252 2253If the network interface stores some valid MAC address (for instance 2254in SROM), this is used as default address if there is NO correspon- 2255ding setting in the environment; if the corresponding environment 2256variable is set, this overrides the settings in the card; that means: 2257 2258o If the SROM has a valid MAC address, and there is no address in the 2259 environment, the SROM's address is used. 2260 2261o If there is no valid address in the SROM, and a definition in the 2262 environment exists, then the value from the environment variable is 2263 used. 2264 2265o If both the SROM and the environment contain a MAC address, and 2266 both addresses are the same, this MAC address is used. 2267 2268o If both the SROM and the environment contain a MAC address, and the 2269 addresses differ, the value from the environment is used and a 2270 warning is printed. 2271 2272o If neither SROM nor the environment contain a MAC address, an error 2273 is raised. 2274 2275 2276Image Formats: 2277============== 2278 2279The "boot" commands of this monitor operate on "image" files which 2280can be basicly anything, preceeded by a special header; see the 2281definitions in include/image.h for details; basicly, the header 2282defines the following image properties: 2283 2284* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 2285 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 2286 LynxOS, pSOS, QNX, RTEMS, ARTOS; 2287 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, ARTOS, LynxOS). 2288* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86, 2289 IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 2290 Currently supported: ARM, Intel x86, MIPS, NIOS, PowerPC). 2291* Compression Type (uncompressed, gzip, bzip2) 2292* Load Address 2293* Entry Point 2294* Image Name 2295* Image Timestamp 2296 2297The header is marked by a special Magic Number, and both the header 2298and the data portions of the image are secured against corruption by 2299CRC32 checksums. 2300 2301 2302Linux Support: 2303============== 2304 2305Although U-Boot should support any OS or standalone application 2306easily, the main focus has always been on Linux during the design of 2307U-Boot. 2308 2309U-Boot includes many features that so far have been part of some 2310special "boot loader" code within the Linux kernel. Also, any 2311"initrd" images to be used are no longer part of one big Linux image; 2312instead, kernel and "initrd" are separate images. This implementation 2313serves several purposes: 2314 2315- the same features can be used for other OS or standalone 2316 applications (for instance: using compressed images to reduce the 2317 Flash memory footprint) 2318 2319- it becomes much easier to port new Linux kernel versions because 2320 lots of low-level, hardware dependent stuff are done by U-Boot 2321 2322- the same Linux kernel image can now be used with different "initrd" 2323 images; of course this also means that different kernel images can 2324 be run with the same "initrd". This makes testing easier (you don't 2325 have to build a new "zImage.initrd" Linux image when you just 2326 change a file in your "initrd"). Also, a field-upgrade of the 2327 software is easier now. 2328 2329 2330Linux HOWTO: 2331============ 2332 2333Porting Linux to U-Boot based systems: 2334--------------------------------------- 2335 2336U-Boot cannot save you from doing all the necessary modifications to 2337configure the Linux device drivers for use with your target hardware 2338(no, we don't intend to provide a full virtual machine interface to 2339Linux :-). 2340 2341But now you can ignore ALL boot loader code (in arch/ppc/mbxboot). 2342 2343Just make sure your machine specific header file (for instance 2344include/asm-ppc/tqm8xx.h) includes the same definition of the Board 2345Information structure as we define in include/u-boot.h, and make 2346sure that your definition of IMAP_ADDR uses the same value as your 2347U-Boot configuration in CFG_IMMR. 2348 2349 2350Configuring the Linux kernel: 2351----------------------------- 2352 2353No specific requirements for U-Boot. Make sure you have some root 2354device (initial ramdisk, NFS) for your target system. 2355 2356 2357Building a Linux Image: 2358----------------------- 2359 2360With U-Boot, "normal" build targets like "zImage" or "bzImage" are 2361not used. If you use recent kernel source, a new build target 2362"uImage" will exist which automatically builds an image usable by 2363U-Boot. Most older kernels also have support for a "pImage" target, 2364which was introduced for our predecessor project PPCBoot and uses a 2365100% compatible format. 2366 2367Example: 2368 2369 make TQM850L_config 2370 make oldconfig 2371 make dep 2372 make uImage 2373 2374The "uImage" build target uses a special tool (in 'tools/mkimage') to 2375encapsulate a compressed Linux kernel image with header information, 2376CRC32 checksum etc. for use with U-Boot. This is what we are doing: 2377 2378* build a standard "vmlinux" kernel image (in ELF binary format): 2379 2380* convert the kernel into a raw binary image: 2381 2382 ${CROSS_COMPILE}-objcopy -O binary \ 2383 -R .note -R .comment \ 2384 -S vmlinux linux.bin 2385 2386* compress the binary image: 2387 2388 gzip -9 linux.bin 2389 2390* package compressed binary image for U-Boot: 2391 2392 mkimage -A ppc -O linux -T kernel -C gzip \ 2393 -a 0 -e 0 -n "Linux Kernel Image" \ 2394 -d linux.bin.gz uImage 2395 2396 2397The "mkimage" tool can also be used to create ramdisk images for use 2398with U-Boot, either separated from the Linux kernel image, or 2399combined into one file. "mkimage" encapsulates the images with a 64 2400byte header containing information about target architecture, 2401operating system, image type, compression method, entry points, time 2402stamp, CRC32 checksums, etc. 2403 2404"mkimage" can be called in two ways: to verify existing images and 2405print the header information, or to build new images. 2406 2407In the first form (with "-l" option) mkimage lists the information 2408contained in the header of an existing U-Boot image; this includes 2409checksum verification: 2410 2411 tools/mkimage -l image 2412 -l ==> list image header information 2413 2414The second form (with "-d" option) is used to build a U-Boot image 2415from a "data file" which is used as image payload: 2416 2417 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 2418 -n name -d data_file image 2419 -A ==> set architecture to 'arch' 2420 -O ==> set operating system to 'os' 2421 -T ==> set image type to 'type' 2422 -C ==> set compression type 'comp' 2423 -a ==> set load address to 'addr' (hex) 2424 -e ==> set entry point to 'ep' (hex) 2425 -n ==> set image name to 'name' 2426 -d ==> use image data from 'datafile' 2427 2428Right now, all Linux kernels use the same load address (0x00000000), 2429but the entry point address depends on the kernel version: 2430 2431- 2.2.x kernels have the entry point at 0x0000000C, 2432- 2.3.x and later kernels have the entry point at 0x00000000. 2433 2434So a typical call to build a U-Boot image would read: 2435 2436 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2437 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 2438 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz \ 2439 > examples/uImage.TQM850L 2440 Image Name: 2.4.4 kernel for TQM850L 2441 Created: Wed Jul 19 02:34:59 2000 2442 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2443 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2444 Load Address: 0x00000000 2445 Entry Point: 0x00000000 2446 2447To verify the contents of the image (or check for corruption): 2448 2449 -> tools/mkimage -l examples/uImage.TQM850L 2450 Image Name: 2.4.4 kernel for TQM850L 2451 Created: Wed Jul 19 02:34:59 2000 2452 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2453 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 2454 Load Address: 0x00000000 2455 Entry Point: 0x00000000 2456 2457NOTE: for embedded systems where boot time is critical you can trade 2458speed for memory and install an UNCOMPRESSED image instead: this 2459needs more space in Flash, but boots much faster since it does not 2460need to be uncompressed: 2461 2462 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux.gz 2463 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 2464 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 2465 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/ppc/coffboot/vmlinux \ 2466 > examples/uImage.TQM850L-uncompressed 2467 Image Name: 2.4.4 kernel for TQM850L 2468 Created: Wed Jul 19 02:34:59 2000 2469 Image Type: PowerPC Linux Kernel Image (uncompressed) 2470 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 2471 Load Address: 0x00000000 2472 Entry Point: 0x00000000 2473 2474 2475Similar you can build U-Boot images from a 'ramdisk.image.gz' file 2476when your kernel is intended to use an initial ramdisk: 2477 2478 -> tools/mkimage -n 'Simple Ramdisk Image' \ 2479 > -A ppc -O linux -T ramdisk -C gzip \ 2480 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 2481 Image Name: Simple Ramdisk Image 2482 Created: Wed Jan 12 14:01:50 2000 2483 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2484 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 2485 Load Address: 0x00000000 2486 Entry Point: 0x00000000 2487 2488 2489Installing a Linux Image: 2490------------------------- 2491 2492To downloading a U-Boot image over the serial (console) interface, 2493you must convert the image to S-Record format: 2494 2495 objcopy -I binary -O srec examples/image examples/image.srec 2496 2497The 'objcopy' does not understand the information in the U-Boot 2498image header, so the resulting S-Record file will be relative to 2499address 0x00000000. To load it to a given address, you need to 2500specify the target address as 'offset' parameter with the 'loads' 2501command. 2502 2503Example: install the image to address 0x40100000 (which on the 2504TQM8xxL is in the first Flash bank): 2505 2506 => erase 40100000 401FFFFF 2507 2508 .......... done 2509 Erased 8 sectors 2510 2511 => loads 40100000 2512 ## Ready for S-Record download ... 2513 ~>examples/image.srec 2514 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 2515 ... 2516 15989 15990 15991 15992 2517 [file transfer complete] 2518 [connected] 2519 ## Start Addr = 0x00000000 2520 2521 2522You can check the success of the download using the 'iminfo' command; 2523this includes a checksum verification so you can be sure no data 2524corruption happened: 2525 2526 => imi 40100000 2527 2528 ## Checking Image at 40100000 ... 2529 Image Name: 2.2.13 for initrd on TQM850L 2530 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2531 Data Size: 335725 Bytes = 327 kB = 0 MB 2532 Load Address: 00000000 2533 Entry Point: 0000000c 2534 Verifying Checksum ... OK 2535 2536 2537Boot Linux: 2538----------- 2539 2540The "bootm" command is used to boot an application that is stored in 2541memory (RAM or Flash). In case of a Linux kernel image, the contents 2542of the "bootargs" environment variable is passed to the kernel as 2543parameters. You can check and modify this variable using the 2544"printenv" and "setenv" commands: 2545 2546 2547 => printenv bootargs 2548 bootargs=root=/dev/ram 2549 2550 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2551 2552 => printenv bootargs 2553 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2554 2555 => bootm 40020000 2556 ## Booting Linux kernel at 40020000 ... 2557 Image Name: 2.2.13 for NFS on TQM850L 2558 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2559 Data Size: 381681 Bytes = 372 kB = 0 MB 2560 Load Address: 00000000 2561 Entry Point: 0000000c 2562 Verifying Checksum ... OK 2563 Uncompressing Kernel Image ... OK 2564 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 2565 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 2566 time_init: decrementer frequency = 187500000/60 2567 Calibrating delay loop... 49.77 BogoMIPS 2568 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 2569 ... 2570 2571If you want to boot a Linux kernel with initial ram disk, you pass 2572the memory addresses of both the kernel and the initrd image (PPBCOOT 2573format!) to the "bootm" command: 2574 2575 => imi 40100000 40200000 2576 2577 ## Checking Image at 40100000 ... 2578 Image Name: 2.2.13 for initrd on TQM850L 2579 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2580 Data Size: 335725 Bytes = 327 kB = 0 MB 2581 Load Address: 00000000 2582 Entry Point: 0000000c 2583 Verifying Checksum ... OK 2584 2585 ## Checking Image at 40200000 ... 2586 Image Name: Simple Ramdisk Image 2587 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2588 Data Size: 566530 Bytes = 553 kB = 0 MB 2589 Load Address: 00000000 2590 Entry Point: 00000000 2591 Verifying Checksum ... OK 2592 2593 => bootm 40100000 40200000 2594 ## Booting Linux kernel at 40100000 ... 2595 Image Name: 2.2.13 for initrd on TQM850L 2596 Image Type: PowerPC Linux Kernel Image (gzip compressed) 2597 Data Size: 335725 Bytes = 327 kB = 0 MB 2598 Load Address: 00000000 2599 Entry Point: 0000000c 2600 Verifying Checksum ... OK 2601 Uncompressing Kernel Image ... OK 2602 ## Loading RAMDisk Image at 40200000 ... 2603 Image Name: Simple Ramdisk Image 2604 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 2605 Data Size: 566530 Bytes = 553 kB = 0 MB 2606 Load Address: 00000000 2607 Entry Point: 00000000 2608 Verifying Checksum ... OK 2609 Loading Ramdisk ... OK 2610 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 2611 Boot arguments: root=/dev/ram 2612 time_init: decrementer frequency = 187500000/60 2613 Calibrating delay loop... 49.77 BogoMIPS 2614 ... 2615 RAMDISK: Compressed image found at block 0 2616 VFS: Mounted root (ext2 filesystem). 2617 2618 bash# 2619 2620More About U-Boot Image Types: 2621------------------------------ 2622 2623U-Boot supports the following image types: 2624 2625 "Standalone Programs" are directly runnable in the environment 2626 provided by U-Boot; it is expected that (if they behave 2627 well) you can continue to work in U-Boot after return from 2628 the Standalone Program. 2629 "OS Kernel Images" are usually images of some Embedded OS which 2630 will take over control completely. Usually these programs 2631 will install their own set of exception handlers, device 2632 drivers, set up the MMU, etc. - this means, that you cannot 2633 expect to re-enter U-Boot except by resetting the CPU. 2634 "RAMDisk Images" are more or less just data blocks, and their 2635 parameters (address, size) are passed to an OS kernel that is 2636 being started. 2637 "Multi-File Images" contain several images, typically an OS 2638 (Linux) kernel image and one or more data images like 2639 RAMDisks. This construct is useful for instance when you want 2640 to boot over the network using BOOTP etc., where the boot 2641 server provides just a single image file, but you want to get 2642 for instance an OS kernel and a RAMDisk image. 2643 2644 "Multi-File Images" start with a list of image sizes, each 2645 image size (in bytes) specified by an "uint32_t" in network 2646 byte order. This list is terminated by an "(uint32_t)0". 2647 Immediately after the terminating 0 follow the images, one by 2648 one, all aligned on "uint32_t" boundaries (size rounded up to 2649 a multiple of 4 bytes). 2650 2651 "Firmware Images" are binary images containing firmware (like 2652 U-Boot or FPGA images) which usually will be programmed to 2653 flash memory. 2654 2655 "Script files" are command sequences that will be executed by 2656 U-Boot's command interpreter; this feature is especially 2657 useful when you configure U-Boot to use a real shell (hush) 2658 as command interpreter. 2659 2660 2661Standalone HOWTO: 2662================= 2663 2664One of the features of U-Boot is that you can dynamically load and 2665run "standalone" applications, which can use some resources of 2666U-Boot like console I/O functions or interrupt services. 2667 2668Two simple examples are included with the sources: 2669 2670"Hello World" Demo: 2671------------------- 2672 2673'examples/hello_world.c' contains a small "Hello World" Demo 2674application; it is automatically compiled when you build U-Boot. 2675It's configured to run at address 0x00040004, so you can play with it 2676like that: 2677 2678 => loads 2679 ## Ready for S-Record download ... 2680 ~>examples/hello_world.srec 2681 1 2 3 4 5 6 7 8 9 10 11 ... 2682 [file transfer complete] 2683 [connected] 2684 ## Start Addr = 0x00040004 2685 2686 => go 40004 Hello World! This is a test. 2687 ## Starting application at 0x00040004 ... 2688 Hello World 2689 argc = 7 2690 argv[0] = "40004" 2691 argv[1] = "Hello" 2692 argv[2] = "World!" 2693 argv[3] = "This" 2694 argv[4] = "is" 2695 argv[5] = "a" 2696 argv[6] = "test." 2697 argv[7] = "<NULL>" 2698 Hit any key to exit ... 2699 2700 ## Application terminated, rc = 0x0 2701 2702Another example, which demonstrates how to register a CPM interrupt 2703handler with the U-Boot code, can be found in 'examples/timer.c'. 2704Here, a CPM timer is set up to generate an interrupt every second. 2705The interrupt service routine is trivial, just printing a '.' 2706character, but this is just a demo program. The application can be 2707controlled by the following keys: 2708 2709 ? - print current values og the CPM Timer registers 2710 b - enable interrupts and start timer 2711 e - stop timer and disable interrupts 2712 q - quit application 2713 2714 => loads 2715 ## Ready for S-Record download ... 2716 ~>examples/timer.srec 2717 1 2 3 4 5 6 7 8 9 10 11 ... 2718 [file transfer complete] 2719 [connected] 2720 ## Start Addr = 0x00040004 2721 2722 => go 40004 2723 ## Starting application at 0x00040004 ... 2724 TIMERS=0xfff00980 2725 Using timer 1 2726 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 2727 2728Hit 'b': 2729 [q, b, e, ?] Set interval 1000000 us 2730 Enabling timer 2731Hit '?': 2732 [q, b, e, ?] ........ 2733 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 2734Hit '?': 2735 [q, b, e, ?] . 2736 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 2737Hit '?': 2738 [q, b, e, ?] . 2739 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 2740Hit '?': 2741 [q, b, e, ?] . 2742 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 2743Hit 'e': 2744 [q, b, e, ?] ...Stopping timer 2745Hit 'q': 2746 [q, b, e, ?] ## Application terminated, rc = 0x0 2747 2748 2749Minicom warning: 2750================ 2751 2752Over time, many people have reported problems when trying to use the 2753"minicom" terminal emulation program for serial download. I (wd) 2754consider minicom to be broken, and recommend not to use it. Under 2755Unix, I recommend to use C-Kermit for general purpose use (and 2756especially for kermit binary protocol download ("loadb" command), and 2757use "cu" for S-Record download ("loads" command). 2758 2759Nevertheless, if you absolutely want to use it try adding this 2760configuration to your "File transfer protocols" section: 2761 2762 Name Program Name U/D FullScr IO-Red. Multi 2763 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 2764 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 2765 2766 2767NetBSD Notes: 2768============= 2769 2770Starting at version 0.9.2, U-Boot supports NetBSD both as host 2771(build U-Boot) and target system (boots NetBSD/mpc8xx). 2772 2773Building requires a cross environment; it is known to work on 2774NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 2775need gmake since the Makefiles are not compatible with BSD make). 2776Note that the cross-powerpc package does not install include files; 2777attempting to build U-Boot will fail because <machine/ansi.h> is 2778missing. This file has to be installed and patched manually: 2779 2780 # cd /usr/pkg/cross/powerpc-netbsd/include 2781 # mkdir powerpc 2782 # ln -s powerpc machine 2783 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 2784 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 2785 2786Native builds *don't* work due to incompatibilities between native 2787and U-Boot include files. 2788 2789Booting assumes that (the first part of) the image booted is a 2790stage-2 loader which in turn loads and then invokes the kernel 2791proper. Loader sources will eventually appear in the NetBSD source 2792tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 2793meantime, send mail to bruno@exet-ag.de and/or wd@denx.de for 2794details. 2795 2796 2797Implementation Internals: 2798========================= 2799 2800The following is not intended to be a complete description of every 2801implementation detail. However, it should help to understand the 2802inner workings of U-Boot and make it easier to port it to custom 2803hardware. 2804 2805 2806Initial Stack, Global Data: 2807--------------------------- 2808 2809The implementation of U-Boot is complicated by the fact that U-Boot 2810starts running out of ROM (flash memory), usually without access to 2811system RAM (because the memory controller is not initialized yet). 2812This means that we don't have writable Data or BSS segments, and BSS 2813is not initialized as zero. To be able to get a C environment working 2814at all, we have to allocate at least a minimal stack. Implementation 2815options for this are defined and restricted by the CPU used: Some CPU 2816models provide on-chip memory (like the IMMR area on MPC8xx and 2817MPC826x processors), on others (parts of) the data cache can be 2818locked as (mis-) used as memory, etc. 2819 2820 Chris Hallinan posted a good summary of these issues to the 2821 u-boot-users mailing list: 2822 2823 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 2824 From: "Chris Hallinan" <clh@net1plus.com> 2825 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 2826 ... 2827 2828 Correct me if I'm wrong, folks, but the way I understand it 2829 is this: Using DCACHE as initial RAM for Stack, etc, does not 2830 require any physical RAM backing up the cache. The cleverness 2831 is that the cache is being used as a temporary supply of 2832 necessary storage before the SDRAM controller is setup. It's 2833 beyond the scope of this list to expain the details, but you 2834 can see how this works by studying the cache architecture and 2835 operation in the architecture and processor-specific manuals. 2836 2837 OCM is On Chip Memory, which I believe the 405GP has 4K. It 2838 is another option for the system designer to use as an 2839 initial stack/ram area prior to SDRAM being available. Either 2840 option should work for you. Using CS 4 should be fine if your 2841 board designers haven't used it for something that would 2842 cause you grief during the initial boot! It is frequently not 2843 used. 2844 2845 CFG_INIT_RAM_ADDR should be somewhere that won't interfere 2846 with your processor/board/system design. The default value 2847 you will find in any recent u-boot distribution in 2848 Walnut405.h should work for you. I'd set it to a value larger 2849 than your SDRAM module. If you have a 64MB SDRAM module, set 2850 it above 400_0000. Just make sure your board has no resources 2851 that are supposed to respond to that address! That code in 2852 start.S has been around a while and should work as is when 2853 you get the config right. 2854 2855 -Chris Hallinan 2856 DS4.COM, Inc. 2857 2858It is essential to remember this, since it has some impact on the C 2859code for the initialization procedures: 2860 2861* Initialized global data (data segment) is read-only. Do not attempt 2862 to write it. 2863 2864* Do not use any unitialized global data (or implicitely initialized 2865 as zero data - BSS segment) at all - this is undefined, initiali- 2866 zation is performed later (when relocating to RAM). 2867 2868* Stack space is very limited. Avoid big data buffers or things like 2869 that. 2870 2871Having only the stack as writable memory limits means we cannot use 2872normal global data to share information beween the code. But it 2873turned out that the implementation of U-Boot can be greatly 2874simplified by making a global data structure (gd_t) available to all 2875functions. We could pass a pointer to this data as argument to _all_ 2876functions, but this would bloat the code. Instead we use a feature of 2877the GCC compiler (Global Register Variables) to share the data: we 2878place a pointer (gd) to the global data into a register which we 2879reserve for this purpose. 2880 2881When choosing a register for such a purpose we are restricted by the 2882relevant (E)ABI specifications for the current architecture, and by 2883GCC's implementation. 2884 2885For PowerPC, the following registers have specific use: 2886 R1: stack pointer 2887 R2: TOC pointer 2888 R3-R4: parameter passing and return values 2889 R5-R10: parameter passing 2890 R13: small data area pointer 2891 R30: GOT pointer 2892 R31: frame pointer 2893 2894 (U-Boot also uses R14 as internal GOT pointer.) 2895 2896 ==> U-Boot will use R29 to hold a pointer to the global data 2897 2898 Note: on PPC, we could use a static initializer (since the 2899 address of the global data structure is known at compile time), 2900 but it turned out that reserving a register results in somewhat 2901 smaller code - although the code savings are not that big (on 2902 average for all boards 752 bytes for the whole U-Boot image, 2903 624 text + 127 data). 2904 2905On ARM, the following registers are used: 2906 2907 R0: function argument word/integer result 2908 R1-R3: function argument word 2909 R9: GOT pointer 2910 R10: stack limit (used only if stack checking if enabled) 2911 R11: argument (frame) pointer 2912 R12: temporary workspace 2913 R13: stack pointer 2914 R14: link register 2915 R15: program counter 2916 2917 ==> U-Boot will use R8 to hold a pointer to the global data 2918 2919 2920Memory Management: 2921------------------ 2922 2923U-Boot runs in system state and uses physical addresses, i.e. the 2924MMU is not used either for address mapping nor for memory protection. 2925 2926The available memory is mapped to fixed addresses using the memory 2927controller. In this process, a contiguous block is formed for each 2928memory type (Flash, SDRAM, SRAM), even when it consists of several 2929physical memory banks. 2930 2931U-Boot is installed in the first 128 kB of the first Flash bank (on 2932TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 2933booting and sizing and initializing DRAM, the code relocates itself 2934to the upper end of DRAM. Immediately below the U-Boot code some 2935memory is reserved for use by malloc() [see CFG_MALLOC_LEN 2936configuration setting]. Below that, a structure with global Board 2937Info data is placed, followed by the stack (growing downward). 2938 2939Additionally, some exception handler code is copied to the low 8 kB 2940of DRAM (0x00000000 ... 0x00001FFF). 2941 2942So a typical memory configuration with 16 MB of DRAM could look like 2943this: 2944 2945 0x0000 0000 Exception Vector code 2946 : 2947 0x0000 1FFF 2948 0x0000 2000 Free for Application Use 2949 : 2950 : 2951 2952 : 2953 : 2954 0x00FB FF20 Monitor Stack (Growing downward) 2955 0x00FB FFAC Board Info Data and permanent copy of global data 2956 0x00FC 0000 Malloc Arena 2957 : 2958 0x00FD FFFF 2959 0x00FE 0000 RAM Copy of Monitor Code 2960 ... eventually: LCD or video framebuffer 2961 ... eventually: pRAM (Protected RAM - unchanged by reset) 2962 0x00FF FFFF [End of RAM] 2963 2964 2965System Initialization: 2966---------------------- 2967 2968In the reset configuration, U-Boot starts at the reset entry point 2969(on most PowerPC systens at address 0x00000100). Because of the reset 2970configuration for CS0# this is a mirror of the onboard Flash memory. 2971To be able to re-map memory U-Boot then jumps to its link address. 2972To be able to implement the initialization code in C, a (small!) 2973initial stack is set up in the internal Dual Ported RAM (in case CPUs 2974which provide such a feature like MPC8xx or MPC8260), or in a locked 2975part of the data cache. After that, U-Boot initializes the CPU core, 2976the caches and the SIU. 2977 2978Next, all (potentially) available memory banks are mapped using a 2979preliminary mapping. For example, we put them on 512 MB boundaries 2980(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 2981on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 2982programmed for SDRAM access. Using the temporary configuration, a 2983simple memory test is run that determines the size of the SDRAM 2984banks. 2985 2986When there is more than one SDRAM bank, and the banks are of 2987different size, the largest is mapped first. For equal size, the first 2988bank (CS2#) is mapped first. The first mapping is always for address 29890x00000000, with any additional banks following immediately to create 2990contiguous memory starting from 0. 2991 2992Then, the monitor installs itself at the upper end of the SDRAM area 2993and allocates memory for use by malloc() and for the global Board 2994Info data; also, the exception vector code is copied to the low RAM 2995pages, and the final stack is set up. 2996 2997Only after this relocation will you have a "normal" C environment; 2998until that you are restricted in several ways, mostly because you are 2999running from ROM, and because the code will have to be relocated to a 3000new address in RAM. 3001 3002 3003U-Boot Porting Guide: 3004---------------------- 3005 3006[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 3007list, October 2002] 3008 3009 3010int main (int argc, char *argv[]) 3011{ 3012 sighandler_t no_more_time; 3013 3014 signal (SIGALRM, no_more_time); 3015 alarm (PROJECT_DEADLINE - toSec (3 * WEEK)); 3016 3017 if (available_money > available_manpower) { 3018 pay consultant to port U-Boot; 3019 return 0; 3020 } 3021 3022 Download latest U-Boot source; 3023 3024 Subscribe to u-boot-users mailing list; 3025 3026 if (clueless) { 3027 email ("Hi, I am new to U-Boot, how do I get started?"); 3028 } 3029 3030 while (learning) { 3031 Read the README file in the top level directory; 3032 Read http://www.denx.de/twiki/bin/view/DULG/Manual ; 3033 Read the source, Luke; 3034 } 3035 3036 if (available_money > toLocalCurrency ($2500)) { 3037 Buy a BDI2000; 3038 } else { 3039 Add a lot of aggravation and time; 3040 } 3041 3042 Create your own board support subdirectory; 3043 3044 Create your own board config file; 3045 3046 while (!running) { 3047 do { 3048 Add / modify source code; 3049 } until (compiles); 3050 Debug; 3051 if (clueless) 3052 email ("Hi, I am having problems..."); 3053 } 3054 Send patch file to Wolfgang; 3055 3056 return 0; 3057} 3058 3059void no_more_time (int sig) 3060{ 3061 hire_a_guru(); 3062} 3063 3064 3065Coding Standards: 3066----------------- 3067 3068All contributions to U-Boot should conform to the Linux kernel 3069coding style; see the file "Documentation/CodingStyle" in your Linux 3070kernel source directory. 3071 3072Please note that U-Boot is implemented in C (and to some small parts 3073in Assembler); no C++ is used, so please do not use C++ style 3074comments (//) in your code. 3075 3076Please also stick to the following formatting rules: 3077- remove any trailing white space 3078- use TAB characters for indentation, not spaces 3079- make sure NOT to use DOS '\r\n' line feeds 3080- do not add more than 2 empty lines to source files 3081- do not add trailing empty lines to source files 3082 3083Submissions which do not conform to the standards may be returned 3084with a request to reformat the changes. 3085 3086 3087Submitting Patches: 3088------------------- 3089 3090Since the number of patches for U-Boot is growing, we need to 3091establish some rules. Submissions which do not conform to these rules 3092may be rejected, even when they contain important and valuable stuff. 3093 3094 3095When you send a patch, please include the following information with 3096it: 3097 3098* For bug fixes: a description of the bug and how your patch fixes 3099 this bug. Please try to include a way of demonstrating that the 3100 patch actually fixes something. 3101 3102* For new features: a description of the feature and your 3103 implementation. 3104 3105* A CHANGELOG entry as plaintext (separate from the patch) 3106 3107* For major contributions, your entry to the CREDITS file 3108 3109* When you add support for a new board, don't forget to add this 3110 board to the MAKEALL script, too. 3111 3112* If your patch adds new configuration options, don't forget to 3113 document these in the README file. 3114 3115* The patch itself. If you are accessing the CVS repository use "cvs 3116 update; cvs diff -puRN"; else, use "diff -purN OLD NEW". If your 3117 version of diff does not support these options, then get the latest 3118 version of GNU diff. 3119 3120 The current directory when running this command shall be the top 3121 level directory of the U-Boot source tree, or it's parent directory 3122 (i. e. please make sure that your patch includes sufficient 3123 directory information for the affected files). 3124 3125 We accept patches as plain text, MIME attachments or as uuencoded 3126 gzipped text. 3127 3128* If one logical set of modifications affects or creates several 3129 files, all these changes shall be submitted in a SINGLE patch file. 3130 3131* Changesets that contain different, unrelated modifications shall be 3132 submitted as SEPARATE patches, one patch per changeset. 3133 3134 3135Notes: 3136 3137* Before sending the patch, run the MAKEALL script on your patched 3138 source tree and make sure that no errors or warnings are reported 3139 for any of the boards. 3140 3141* Keep your modifications to the necessary minimum: A patch 3142 containing several unrelated changes or arbitrary reformats will be 3143 returned with a request to re-formatting / split it. 3144 3145* If you modify existing code, make sure that your new code does not 3146 add to the memory footprint of the code ;-) Small is beautiful! 3147 When adding new features, these should compile conditionally only 3148 (using #ifdef), and the resulting code with the new feature 3149 disabled must not need more memory than the old code without your 3150 modification. 3151