1# 2# (C) Copyright 2000 - 2011 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# See file CREDITS for list of people who contributed to this 6# project. 7# 8# This program is free software; you can redistribute it and/or 9# modify it under the terms of the GNU General Public License as 10# published by the Free Software Foundation; either version 2 of 11# the License, or (at your option) any later version. 12# 13# This program is distributed in the hope that it will be useful, 14# but WITHOUT ANY WARRANTY; without even the implied warranty of 15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16# GNU General Public License for more details. 17# 18# You should have received a copy of the GNU General Public License 19# along with this program; if not, write to the Free Software 20# Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21# MA 02111-1307 USA 22# 23 24Summary: 25======== 26 27This directory contains the source code for U-Boot, a boot loader for 28Embedded boards based on PowerPC, ARM, MIPS and several other 29processors, which can be installed in a boot ROM and used to 30initialize and test the hardware or to download and run application 31code. 32 33The development of U-Boot is closely related to Linux: some parts of 34the source code originate in the Linux source tree, we have some 35header files in common, and special provision has been made to 36support booting of Linux images. 37 38Some attention has been paid to make this software easily 39configurable and extendable. For instance, all monitor commands are 40implemented with the same call interface, so that it's very easy to 41add new commands. Also, instead of permanently adding rarely used 42code (for instance hardware test utilities) to the monitor, you can 43load and run it dynamically. 44 45 46Status: 47======= 48 49In general, all boards for which a configuration option exists in the 50Makefile have been tested to some extent and can be considered 51"working". In fact, many of them are used in production systems. 52 53In case of problems see the CHANGELOG and CREDITS files to find out 54who contributed the specific port. The MAINTAINERS file lists board 55maintainers. 56 57 58Where to get help: 59================== 60 61In case you have questions about, problems with or contributions for 62U-Boot you should send a message to the U-Boot mailing list at 63<u-boot@lists.denx.de>. There is also an archive of previous traffic 64on the mailing list - please search the archive before asking FAQ's. 65Please see http://lists.denx.de/pipermail/u-boot and 66http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 67 68 69Where to get source code: 70========================= 71 72The U-Boot source code is maintained in the git repository at 73git://www.denx.de/git/u-boot.git ; you can browse it online at 74http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 75 76The "snapshot" links on this page allow you to download tarballs of 77any version you might be interested in. Official releases are also 78available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 79directory. 80 81Pre-built (and tested) images are available from 82ftp://ftp.denx.de/pub/u-boot/images/ 83 84 85Where we come from: 86=================== 87 88- start from 8xxrom sources 89- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 90- clean up code 91- make it easier to add custom boards 92- make it possible to add other [PowerPC] CPUs 93- extend functions, especially: 94 * Provide extended interface to Linux boot loader 95 * S-Record download 96 * network boot 97 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 98- create ARMBoot project (http://sourceforge.net/projects/armboot) 99- add other CPU families (starting with ARM) 100- create U-Boot project (http://sourceforge.net/projects/u-boot) 101- current project page: see http://www.denx.de/wiki/U-Boot 102 103 104Names and Spelling: 105=================== 106 107The "official" name of this project is "Das U-Boot". The spelling 108"U-Boot" shall be used in all written text (documentation, comments 109in source files etc.). Example: 110 111 This is the README file for the U-Boot project. 112 113File names etc. shall be based on the string "u-boot". Examples: 114 115 include/asm-ppc/u-boot.h 116 117 #include <asm/u-boot.h> 118 119Variable names, preprocessor constants etc. shall be either based on 120the string "u_boot" or on "U_BOOT". Example: 121 122 U_BOOT_VERSION u_boot_logo 123 IH_OS_U_BOOT u_boot_hush_start 124 125 126Versioning: 127=========== 128 129Starting with the release in October 2008, the names of the releases 130were changed from numerical release numbers without deeper meaning 131into a time stamp based numbering. Regular releases are identified by 132names consisting of the calendar year and month of the release date. 133Additional fields (if present) indicate release candidates or bug fix 134releases in "stable" maintenance trees. 135 136Examples: 137 U-Boot v2009.11 - Release November 2009 138 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 139 U-Boot v2010.09-rc1 - Release candiate 1 for September 2010 release 140 141 142Directory Hierarchy: 143==================== 144 145/arch Architecture specific files 146 /arm Files generic to ARM architecture 147 /cpu CPU specific files 148 /arm720t Files specific to ARM 720 CPUs 149 /arm920t Files specific to ARM 920 CPUs 150 /at91 Files specific to Atmel AT91RM9200 CPU 151 /imx Files specific to Freescale MC9328 i.MX CPUs 152 /s3c24x0 Files specific to Samsung S3C24X0 CPUs 153 /arm925t Files specific to ARM 925 CPUs 154 /arm926ejs Files specific to ARM 926 CPUs 155 /arm1136 Files specific to ARM 1136 CPUs 156 /ixp Files specific to Intel XScale IXP CPUs 157 /pxa Files specific to Intel XScale PXA CPUs 158 /s3c44b0 Files specific to Samsung S3C44B0 CPUs 159 /sa1100 Files specific to Intel StrongARM SA1100 CPUs 160 /lib Architecture specific library files 161 /avr32 Files generic to AVR32 architecture 162 /cpu CPU specific files 163 /lib Architecture specific library files 164 /blackfin Files generic to Analog Devices Blackfin architecture 165 /cpu CPU specific files 166 /lib Architecture specific library files 167 /x86 Files generic to x86 architecture 168 /cpu CPU specific files 169 /lib Architecture specific library files 170 /m68k Files generic to m68k architecture 171 /cpu CPU specific files 172 /mcf52x2 Files specific to Freescale ColdFire MCF52x2 CPUs 173 /mcf5227x Files specific to Freescale ColdFire MCF5227x CPUs 174 /mcf532x Files specific to Freescale ColdFire MCF5329 CPUs 175 /mcf5445x Files specific to Freescale ColdFire MCF5445x CPUs 176 /mcf547x_8x Files specific to Freescale ColdFire MCF547x_8x CPUs 177 /lib Architecture specific library files 178 /microblaze Files generic to microblaze architecture 179 /cpu CPU specific files 180 /lib Architecture specific library files 181 /mips Files generic to MIPS architecture 182 /cpu CPU specific files 183 /mips32 Files specific to MIPS32 CPUs 184 /xburst Files specific to Ingenic XBurst CPUs 185 /lib Architecture specific library files 186 /nds32 Files generic to NDS32 architecture 187 /cpu CPU specific files 188 /n1213 Files specific to Andes Technology N1213 CPUs 189 /lib Architecture specific library files 190 /nios2 Files generic to Altera NIOS2 architecture 191 /cpu CPU specific files 192 /lib Architecture specific library files 193 /powerpc Files generic to PowerPC architecture 194 /cpu CPU specific files 195 /74xx_7xx Files specific to Freescale MPC74xx and 7xx CPUs 196 /mpc5xx Files specific to Freescale MPC5xx CPUs 197 /mpc5xxx Files specific to Freescale MPC5xxx CPUs 198 /mpc8xx Files specific to Freescale MPC8xx CPUs 199 /mpc8220 Files specific to Freescale MPC8220 CPUs 200 /mpc824x Files specific to Freescale MPC824x CPUs 201 /mpc8260 Files specific to Freescale MPC8260 CPUs 202 /mpc85xx Files specific to Freescale MPC85xx CPUs 203 /ppc4xx Files specific to AMCC PowerPC 4xx CPUs 204 /lib Architecture specific library files 205 /sh Files generic to SH architecture 206 /cpu CPU specific files 207 /sh2 Files specific to sh2 CPUs 208 /sh3 Files specific to sh3 CPUs 209 /sh4 Files specific to sh4 CPUs 210 /lib Architecture specific library files 211 /sparc Files generic to SPARC architecture 212 /cpu CPU specific files 213 /leon2 Files specific to Gaisler LEON2 SPARC CPU 214 /leon3 Files specific to Gaisler LEON3 SPARC CPU 215 /lib Architecture specific library files 216/api Machine/arch independent API for external apps 217/board Board dependent files 218/common Misc architecture independent functions 219/disk Code for disk drive partition handling 220/doc Documentation (don't expect too much) 221/drivers Commonly used device drivers 222/examples Example code for standalone applications, etc. 223/fs Filesystem code (cramfs, ext2, jffs2, etc.) 224/include Header Files 225/lib Files generic to all architectures 226 /libfdt Library files to support flattened device trees 227 /lzma Library files to support LZMA decompression 228 /lzo Library files to support LZO decompression 229/net Networking code 230/post Power On Self Test 231/rtc Real Time Clock drivers 232/tools Tools to build S-Record or U-Boot images, etc. 233 234Software Configuration: 235======================= 236 237Configuration is usually done using C preprocessor defines; the 238rationale behind that is to avoid dead code whenever possible. 239 240There are two classes of configuration variables: 241 242* Configuration _OPTIONS_: 243 These are selectable by the user and have names beginning with 244 "CONFIG_". 245 246* Configuration _SETTINGS_: 247 These depend on the hardware etc. and should not be meddled with if 248 you don't know what you're doing; they have names beginning with 249 "CONFIG_SYS_". 250 251Later we will add a configuration tool - probably similar to or even 252identical to what's used for the Linux kernel. Right now, we have to 253do the configuration by hand, which means creating some symbolic 254links and editing some configuration files. We use the TQM8xxL boards 255as an example here. 256 257 258Selection of Processor Architecture and Board Type: 259--------------------------------------------------- 260 261For all supported boards there are ready-to-use default 262configurations available; just type "make <board_name>_config". 263 264Example: For a TQM823L module type: 265 266 cd u-boot 267 make TQM823L_config 268 269For the Cogent platform, you need to specify the CPU type as well; 270e.g. "make cogent_mpc8xx_config". And also configure the cogent 271directory according to the instructions in cogent/README. 272 273 274Configuration Options: 275---------------------- 276 277Configuration depends on the combination of board and CPU type; all 278such information is kept in a configuration file 279"include/configs/<board_name>.h". 280 281Example: For a TQM823L module, all configuration settings are in 282"include/configs/TQM823L.h". 283 284 285Many of the options are named exactly as the corresponding Linux 286kernel configuration options. The intention is to make it easier to 287build a config tool - later. 288 289 290The following options need to be configured: 291 292- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 293 294- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 295 296- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 297 Define exactly one, e.g. CONFIG_ATSTK1002 298 299- CPU Module Type: (if CONFIG_COGENT is defined) 300 Define exactly one of 301 CONFIG_CMA286_60_OLD 302--- FIXME --- not tested yet: 303 CONFIG_CMA286_60, CONFIG_CMA286_21, CONFIG_CMA286_60P, 304 CONFIG_CMA287_23, CONFIG_CMA287_50 305 306- Motherboard Type: (if CONFIG_COGENT is defined) 307 Define exactly one of 308 CONFIG_CMA101, CONFIG_CMA102 309 310- Motherboard I/O Modules: (if CONFIG_COGENT is defined) 311 Define one or more of 312 CONFIG_CMA302 313 314- Motherboard Options: (if CONFIG_CMA101 or CONFIG_CMA102 are defined) 315 Define one or more of 316 CONFIG_LCD_HEARTBEAT - update a character position on 317 the LCD display every second with 318 a "rotator" |\-/|\-/ 319 320- Board flavour: (if CONFIG_MPC8260ADS is defined) 321 CONFIG_ADSTYPE 322 Possible values are: 323 CONFIG_SYS_8260ADS - original MPC8260ADS 324 CONFIG_SYS_8266ADS - MPC8266ADS 325 CONFIG_SYS_PQ2FADS - PQ2FADS-ZU or PQ2FADS-VR 326 CONFIG_SYS_8272ADS - MPC8272ADS 327 328- Marvell Family Member 329 CONFIG_SYS_MVFS - define it if you want to enable 330 multiple fs option at one time 331 for marvell soc family 332 333- MPC824X Family Member (if CONFIG_MPC824X is defined) 334 Define exactly one of 335 CONFIG_MPC8240, CONFIG_MPC8245 336 337- 8xx CPU Options: (if using an MPC8xx CPU) 338 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 339 get_gclk_freq() cannot work 340 e.g. if there is no 32KHz 341 reference PIT/RTC clock 342 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 343 or XTAL/EXTAL) 344 345- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 346 CONFIG_SYS_8xx_CPUCLK_MIN 347 CONFIG_SYS_8xx_CPUCLK_MAX 348 CONFIG_8xx_CPUCLK_DEFAULT 349 See doc/README.MPC866 350 351 CONFIG_SYS_MEASURE_CPUCLK 352 353 Define this to measure the actual CPU clock instead 354 of relying on the correctness of the configured 355 values. Mostly useful for board bringup to make sure 356 the PLL is locked at the intended frequency. Note 357 that this requires a (stable) reference clock (32 kHz 358 RTC clock or CONFIG_SYS_8XX_XIN) 359 360 CONFIG_SYS_DELAYED_ICACHE 361 362 Define this option if you want to enable the 363 ICache only when Code runs from RAM. 364 365- 85xx CPU Options: 366 CONFIG_SYS_FSL_TBCLK_DIV 367 368 Defines the core time base clock divider ratio compared to the 369 system clock. On most PQ3 devices this is 8, on newer QorIQ 370 devices it can be 16 or 32. The ratio varies from SoC to Soc. 371 372 CONFIG_SYS_FSL_PCIE_COMPAT 373 374 Defines the string to utilize when trying to match PCIe device 375 tree nodes for the given platform. 376 377- Intel Monahans options: 378 CONFIG_SYS_MONAHANS_RUN_MODE_OSC_RATIO 379 380 Defines the Monahans run mode to oscillator 381 ratio. Valid values are 8, 16, 24, 31. The core 382 frequency is this value multiplied by 13 MHz. 383 384 CONFIG_SYS_MONAHANS_TURBO_RUN_MODE_RATIO 385 386 Defines the Monahans turbo mode to oscillator 387 ratio. Valid values are 1 (default if undefined) and 388 2. The core frequency as calculated above is multiplied 389 by this value. 390 391- MIPS CPU options: 392 CONFIG_SYS_INIT_SP_OFFSET 393 394 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 395 pointer. This is needed for the temporary stack before 396 relocation. 397 398 CONFIG_SYS_MIPS_CACHE_MODE 399 400 Cache operation mode for the MIPS CPU. 401 See also arch/mips/include/asm/mipsregs.h. 402 Possible values are: 403 CONF_CM_CACHABLE_NO_WA 404 CONF_CM_CACHABLE_WA 405 CONF_CM_UNCACHED 406 CONF_CM_CACHABLE_NONCOHERENT 407 CONF_CM_CACHABLE_CE 408 CONF_CM_CACHABLE_COW 409 CONF_CM_CACHABLE_CUW 410 CONF_CM_CACHABLE_ACCELERATED 411 412 CONFIG_SYS_XWAY_EBU_BOOTCFG 413 414 Special option for Lantiq XWAY SoCs for booting from NOR flash. 415 See also arch/mips/cpu/mips32/start.S. 416 417 CONFIG_XWAY_SWAP_BYTES 418 419 Enable compilation of tools/xway-swap-bytes needed for Lantiq 420 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 421 be swapped if a flash programmer is used. 422 423- Linux Kernel Interface: 424 CONFIG_CLOCKS_IN_MHZ 425 426 U-Boot stores all clock information in Hz 427 internally. For binary compatibility with older Linux 428 kernels (which expect the clocks passed in the 429 bd_info data to be in MHz) the environment variable 430 "clocks_in_mhz" can be defined so that U-Boot 431 converts clock data to MHZ before passing it to the 432 Linux kernel. 433 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 434 "clocks_in_mhz=1" is automatically included in the 435 default environment. 436 437 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 438 439 When transferring memsize parameter to linux, some versions 440 expect it to be in bytes, others in MB. 441 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 442 443 CONFIG_OF_LIBFDT 444 445 New kernel versions are expecting firmware settings to be 446 passed using flattened device trees (based on open firmware 447 concepts). 448 449 CONFIG_OF_LIBFDT 450 * New libfdt-based support 451 * Adds the "fdt" command 452 * The bootm command automatically updates the fdt 453 454 OF_CPU - The proper name of the cpus node (only required for 455 MPC512X and MPC5xxx based boards). 456 OF_SOC - The proper name of the soc node (only required for 457 MPC512X and MPC5xxx based boards). 458 OF_TBCLK - The timebase frequency. 459 OF_STDOUT_PATH - The path to the console device 460 461 boards with QUICC Engines require OF_QE to set UCC MAC 462 addresses 463 464 CONFIG_OF_BOARD_SETUP 465 466 Board code has addition modification that it wants to make 467 to the flat device tree before handing it off to the kernel 468 469 CONFIG_OF_BOOT_CPU 470 471 This define fills in the correct boot CPU in the boot 472 param header, the default value is zero if undefined. 473 474 CONFIG_OF_IDE_FIXUP 475 476 U-Boot can detect if an IDE device is present or not. 477 If not, and this new config option is activated, U-Boot 478 removes the ATA node from the DTS before booting Linux, 479 so the Linux IDE driver does not probe the device and 480 crash. This is needed for buggy hardware (uc101) where 481 no pull down resistor is connected to the signal IDE5V_DD7. 482 483 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 484 485 This setting is mandatory for all boards that have only one 486 machine type and must be used to specify the machine type 487 number as it appears in the ARM machine registry 488 (see http://www.arm.linux.org.uk/developer/machines/). 489 Only boards that have multiple machine types supported 490 in a single configuration file and the machine type is 491 runtime discoverable, do not have to use this setting. 492 493- vxWorks boot parameters: 494 495 bootvx constructs a valid bootline using the following 496 environments variables: bootfile, ipaddr, serverip, hostname. 497 It loads the vxWorks image pointed bootfile. 498 499 CONFIG_SYS_VXWORKS_BOOT_DEVICE - The vxworks device name 500 CONFIG_SYS_VXWORKS_MAC_PTR - Ethernet 6 byte MA -address 501 CONFIG_SYS_VXWORKS_SERVERNAME - Name of the server 502 CONFIG_SYS_VXWORKS_BOOT_ADDR - Address of boot parameters 503 504 CONFIG_SYS_VXWORKS_ADD_PARAMS 505 506 Add it at the end of the bootline. E.g "u=username pw=secret" 507 508 Note: If a "bootargs" environment is defined, it will overwride 509 the defaults discussed just above. 510 511- Cache Configuration: 512 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 513 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 514 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 515 516- Cache Configuration for ARM: 517 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 518 controller 519 CONFIG_SYS_PL310_BASE - Physical base address of PL310 520 controller register space 521 522- Serial Ports: 523 CONFIG_PL010_SERIAL 524 525 Define this if you want support for Amba PrimeCell PL010 UARTs. 526 527 CONFIG_PL011_SERIAL 528 529 Define this if you want support for Amba PrimeCell PL011 UARTs. 530 531 CONFIG_PL011_CLOCK 532 533 If you have Amba PrimeCell PL011 UARTs, set this variable to 534 the clock speed of the UARTs. 535 536 CONFIG_PL01x_PORTS 537 538 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 539 define this to a list of base addresses for each (supported) 540 port. See e.g. include/configs/versatile.h 541 542 CONFIG_PL011_SERIAL_RLCR 543 544 Some vendor versions of PL011 serial ports (e.g. ST-Ericsson U8500) 545 have separate receive and transmit line control registers. Set 546 this variable to initialize the extra register. 547 548 CONFIG_PL011_SERIAL_FLUSH_ON_INIT 549 550 On some platforms (e.g. U8500) U-Boot is loaded by a second stage 551 boot loader that has already initialized the UART. Define this 552 variable to flush the UART at init time. 553 554 555- Console Interface: 556 Depending on board, define exactly one serial port 557 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 558 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 559 console by defining CONFIG_8xx_CONS_NONE 560 561 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 562 port routines must be defined elsewhere 563 (i.e. serial_init(), serial_getc(), ...) 564 565 CONFIG_CFB_CONSOLE 566 Enables console device for a color framebuffer. Needs following 567 defines (cf. smiLynxEM, i8042, board/eltec/bab7xx) 568 VIDEO_FB_LITTLE_ENDIAN graphic memory organisation 569 (default big endian) 570 VIDEO_HW_RECTFILL graphic chip supports 571 rectangle fill 572 (cf. smiLynxEM) 573 VIDEO_HW_BITBLT graphic chip supports 574 bit-blit (cf. smiLynxEM) 575 VIDEO_VISIBLE_COLS visible pixel columns 576 (cols=pitch) 577 VIDEO_VISIBLE_ROWS visible pixel rows 578 VIDEO_PIXEL_SIZE bytes per pixel 579 VIDEO_DATA_FORMAT graphic data format 580 (0-5, cf. cfb_console.c) 581 VIDEO_FB_ADRS framebuffer address 582 VIDEO_KBD_INIT_FCT keyboard int fct 583 (i.e. i8042_kbd_init()) 584 VIDEO_TSTC_FCT test char fct 585 (i.e. i8042_tstc) 586 VIDEO_GETC_FCT get char fct 587 (i.e. i8042_getc) 588 CONFIG_CONSOLE_CURSOR cursor drawing on/off 589 (requires blink timer 590 cf. i8042.c) 591 CONFIG_SYS_CONSOLE_BLINK_COUNT blink interval (cf. i8042.c) 592 CONFIG_CONSOLE_TIME display time/date info in 593 upper right corner 594 (requires CONFIG_CMD_DATE) 595 CONFIG_VIDEO_LOGO display Linux logo in 596 upper left corner 597 CONFIG_VIDEO_BMP_LOGO use bmp_logo.h instead of 598 linux_logo.h for logo. 599 Requires CONFIG_VIDEO_LOGO 600 CONFIG_CONSOLE_EXTRA_INFO 601 additional board info beside 602 the logo 603 604 When CONFIG_CFB_CONSOLE is defined, video console is 605 default i/o. Serial console can be forced with 606 environment 'console=serial'. 607 608 When CONFIG_SILENT_CONSOLE is defined, all console 609 messages (by U-Boot and Linux!) can be silenced with 610 the "silent" environment variable. See 611 doc/README.silent for more information. 612 613- Console Baudrate: 614 CONFIG_BAUDRATE - in bps 615 Select one of the baudrates listed in 616 CONFIG_SYS_BAUDRATE_TABLE, see below. 617 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 618 619- Console Rx buffer length 620 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 621 the maximum receive buffer length for the SMC. 622 This option is actual only for 82xx and 8xx possible. 623 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 624 must be defined, to setup the maximum idle timeout for 625 the SMC. 626 627- Pre-Console Buffer: 628 Prior to the console being initialised (i.e. serial UART 629 initialised etc) all console output is silently discarded. 630 Defining CONFIG_PRE_CONSOLE_BUFFER will cause U-Boot to 631 buffer any console messages prior to the console being 632 initialised to a buffer of size CONFIG_PRE_CON_BUF_SZ 633 bytes located at CONFIG_PRE_CON_BUF_ADDR. The buffer is 634 a circular buffer, so if more than CONFIG_PRE_CON_BUF_SZ 635 bytes are output before the console is initialised, the 636 earlier bytes are discarded. 637 638 'Sane' compilers will generate smaller code if 639 CONFIG_PRE_CON_BUF_SZ is a power of 2 640 641- Boot Delay: CONFIG_BOOTDELAY - in seconds 642 Delay before automatically booting the default image; 643 set to -1 to disable autoboot. 644 645 See doc/README.autoboot for these options that 646 work with CONFIG_BOOTDELAY. None are required. 647 CONFIG_BOOT_RETRY_TIME 648 CONFIG_BOOT_RETRY_MIN 649 CONFIG_AUTOBOOT_KEYED 650 CONFIG_AUTOBOOT_PROMPT 651 CONFIG_AUTOBOOT_DELAY_STR 652 CONFIG_AUTOBOOT_STOP_STR 653 CONFIG_AUTOBOOT_DELAY_STR2 654 CONFIG_AUTOBOOT_STOP_STR2 655 CONFIG_ZERO_BOOTDELAY_CHECK 656 CONFIG_RESET_TO_RETRY 657 658- Autoboot Command: 659 CONFIG_BOOTCOMMAND 660 Only needed when CONFIG_BOOTDELAY is enabled; 661 define a command string that is automatically executed 662 when no character is read on the console interface 663 within "Boot Delay" after reset. 664 665 CONFIG_BOOTARGS 666 This can be used to pass arguments to the bootm 667 command. The value of CONFIG_BOOTARGS goes into the 668 environment value "bootargs". 669 670 CONFIG_RAMBOOT and CONFIG_NFSBOOT 671 The value of these goes into the environment as 672 "ramboot" and "nfsboot" respectively, and can be used 673 as a convenience, when switching between booting from 674 RAM and NFS. 675 676- Pre-Boot Commands: 677 CONFIG_PREBOOT 678 679 When this option is #defined, the existence of the 680 environment variable "preboot" will be checked 681 immediately before starting the CONFIG_BOOTDELAY 682 countdown and/or running the auto-boot command resp. 683 entering interactive mode. 684 685 This feature is especially useful when "preboot" is 686 automatically generated or modified. For an example 687 see the LWMON board specific code: here "preboot" is 688 modified when the user holds down a certain 689 combination of keys on the (special) keyboard when 690 booting the systems 691 692- Serial Download Echo Mode: 693 CONFIG_LOADS_ECHO 694 If defined to 1, all characters received during a 695 serial download (using the "loads" command) are 696 echoed back. This might be needed by some terminal 697 emulations (like "cu"), but may as well just take 698 time on others. This setting #define's the initial 699 value of the "loads_echo" environment variable. 700 701- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 702 CONFIG_KGDB_BAUDRATE 703 Select one of the baudrates listed in 704 CONFIG_SYS_BAUDRATE_TABLE, see below. 705 706- Monitor Functions: 707 Monitor commands can be included or excluded 708 from the build by using the #include files 709 "config_cmd_all.h" and #undef'ing unwanted 710 commands, or using "config_cmd_default.h" 711 and augmenting with additional #define's 712 for wanted commands. 713 714 The default command configuration includes all commands 715 except those marked below with a "*". 716 717 CONFIG_CMD_ASKENV * ask for env variable 718 CONFIG_CMD_BDI bdinfo 719 CONFIG_CMD_BEDBUG * Include BedBug Debugger 720 CONFIG_CMD_BMP * BMP support 721 CONFIG_CMD_BSP * Board specific commands 722 CONFIG_CMD_BOOTD bootd 723 CONFIG_CMD_CACHE * icache, dcache 724 CONFIG_CMD_CONSOLE coninfo 725 CONFIG_CMD_CRC32 * crc32 726 CONFIG_CMD_DATE * support for RTC, date/time... 727 CONFIG_CMD_DHCP * DHCP support 728 CONFIG_CMD_DIAG * Diagnostics 729 CONFIG_CMD_DS4510 * ds4510 I2C gpio commands 730 CONFIG_CMD_DS4510_INFO * ds4510 I2C info command 731 CONFIG_CMD_DS4510_MEM * ds4510 I2C eeprom/sram commansd 732 CONFIG_CMD_DS4510_RST * ds4510 I2C rst command 733 CONFIG_CMD_DTT * Digital Therm and Thermostat 734 CONFIG_CMD_ECHO echo arguments 735 CONFIG_CMD_EDITENV edit env variable 736 CONFIG_CMD_EEPROM * EEPROM read/write support 737 CONFIG_CMD_ELF * bootelf, bootvx 738 CONFIG_CMD_EXPORTENV * export the environment 739 CONFIG_CMD_SAVEENV saveenv 740 CONFIG_CMD_FDC * Floppy Disk Support 741 CONFIG_CMD_FAT * FAT partition support 742 CONFIG_CMD_FDOS * Dos diskette Support 743 CONFIG_CMD_FLASH flinfo, erase, protect 744 CONFIG_CMD_FPGA FPGA device initialization support 745 CONFIG_CMD_GO * the 'go' command (exec code) 746 CONFIG_CMD_GREPENV * search environment 747 CONFIG_CMD_HWFLOW * RTS/CTS hw flow control 748 CONFIG_CMD_I2C * I2C serial bus support 749 CONFIG_CMD_IDE * IDE harddisk support 750 CONFIG_CMD_IMI iminfo 751 CONFIG_CMD_IMLS List all found images 752 CONFIG_CMD_IMMAP * IMMR dump support 753 CONFIG_CMD_IMPORTENV * import an environment 754 CONFIG_CMD_IRQ * irqinfo 755 CONFIG_CMD_ITEST Integer/string test of 2 values 756 CONFIG_CMD_JFFS2 * JFFS2 Support 757 CONFIG_CMD_KGDB * kgdb 758 CONFIG_CMD_LDRINFO ldrinfo (display Blackfin loader) 759 CONFIG_CMD_LOADB loadb 760 CONFIG_CMD_LOADS loads 761 CONFIG_CMD_MD5SUM print md5 message digest 762 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 763 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 764 loop, loopw, mtest 765 CONFIG_CMD_MISC Misc functions like sleep etc 766 CONFIG_CMD_MMC * MMC memory mapped support 767 CONFIG_CMD_MII * MII utility commands 768 CONFIG_CMD_MTDPARTS * MTD partition support 769 CONFIG_CMD_NAND * NAND support 770 CONFIG_CMD_NET bootp, tftpboot, rarpboot 771 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 772 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 773 CONFIG_CMD_PCI * pciinfo 774 CONFIG_CMD_PCMCIA * PCMCIA support 775 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 776 host 777 CONFIG_CMD_PORTIO * Port I/O 778 CONFIG_CMD_REGINFO * Register dump 779 CONFIG_CMD_RUN run command in env variable 780 CONFIG_CMD_SAVES * save S record dump 781 CONFIG_CMD_SCSI * SCSI Support 782 CONFIG_CMD_SDRAM * print SDRAM configuration information 783 (requires CONFIG_CMD_I2C) 784 CONFIG_CMD_SETGETDCR Support for DCR Register access 785 (4xx only) 786 CONFIG_CMD_SHA1SUM print sha1 memory digest 787 (requires CONFIG_CMD_MEMORY) 788 CONFIG_CMD_SOURCE "source" command Support 789 CONFIG_CMD_SPI * SPI serial bus support 790 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 791 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 792 CONFIG_CMD_TIME * run command and report execution time 793 CONFIG_CMD_USB * USB support 794 CONFIG_CMD_CDP * Cisco Discover Protocol support 795 CONFIG_CMD_FSL * Microblaze FSL support 796 797 798 EXAMPLE: If you want all functions except of network 799 support you can write: 800 801 #include "config_cmd_all.h" 802 #undef CONFIG_CMD_NET 803 804 Other Commands: 805 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 806 807 Note: Don't enable the "icache" and "dcache" commands 808 (configuration option CONFIG_CMD_CACHE) unless you know 809 what you (and your U-Boot users) are doing. Data 810 cache cannot be enabled on systems like the 8xx or 811 8260 (where accesses to the IMMR region must be 812 uncached), and it cannot be disabled on all other 813 systems where we (mis-) use the data cache to hold an 814 initial stack and some data. 815 816 817 XXX - this list needs to get updated! 818 819- Device tree: 820 CONFIG_OF_CONTROL 821 If this variable is defined, U-Boot will use a device tree 822 to configure its devices, instead of relying on statically 823 compiled #defines in the board file. This option is 824 experimental and only available on a few boards. The device 825 tree is available in the global data as gd->fdt_blob. 826 827 U-Boot needs to get its device tree from somewhere. At present 828 the only way is to embed it in the image with CONFIG_OF_EMBED. 829 830 CONFIG_OF_EMBED 831 If this variable is defined, U-Boot will embed a device tree 832 binary in its image. This device tree file should be in the 833 board directory and called <soc>-<board>.dts. The binary file 834 is then picked up in board_init_f() and made available through 835 the global data structure as gd->blob. 836 837- Watchdog: 838 CONFIG_WATCHDOG 839 If this variable is defined, it enables watchdog 840 support for the SoC. There must be support in the SoC 841 specific code for a watchdog. For the 8xx and 8260 842 CPUs, the SIU Watchdog feature is enabled in the SYPCR 843 register. When supported for a specific SoC is 844 available, then no further board specific code should 845 be needed to use it. 846 847 CONFIG_HW_WATCHDOG 848 When using a watchdog circuitry external to the used 849 SoC, then define this variable and provide board 850 specific code for the "hw_watchdog_reset" function. 851 852- U-Boot Version: 853 CONFIG_VERSION_VARIABLE 854 If this variable is defined, an environment variable 855 named "ver" is created by U-Boot showing the U-Boot 856 version as printed by the "version" command. 857 This variable is readonly. 858 859- Real-Time Clock: 860 861 When CONFIG_CMD_DATE is selected, the type of the RTC 862 has to be selected, too. Define exactly one of the 863 following options: 864 865 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 866 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 867 CONFIG_RTC_MC13783 - use MC13783 RTC 868 CONFIG_RTC_MC146818 - use MC146818 RTC 869 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 870 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 871 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 872 CONFIG_RTC_DS164x - use Dallas DS164x RTC 873 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 874 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 875 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 876 CONFIG_SYS_RV3029_TCR - enable trickle charger on 877 RV3029 RTC. 878 879 Note that if the RTC uses I2C, then the I2C interface 880 must also be configured. See I2C Support, below. 881 882- GPIO Support: 883 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 884 CONFIG_PCA953X_INFO - enable pca953x info command 885 886 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 887 chip-ngpio pairs that tell the PCA953X driver the number of 888 pins supported by a particular chip. 889 890 Note that if the GPIO device uses I2C, then the I2C interface 891 must also be configured. See I2C Support, below. 892 893- Timestamp Support: 894 895 When CONFIG_TIMESTAMP is selected, the timestamp 896 (date and time) of an image is printed by image 897 commands like bootm or iminfo. This option is 898 automatically enabled when you select CONFIG_CMD_DATE . 899 900- Partition Support: 901 CONFIG_MAC_PARTITION and/or CONFIG_DOS_PARTITION 902 and/or CONFIG_ISO_PARTITION and/or CONFIG_EFI_PARTITION 903 904 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 905 CONFIG_CMD_SCSI) you must configure support for at 906 least one partition type as well. 907 908- IDE Reset method: 909 CONFIG_IDE_RESET_ROUTINE - this is defined in several 910 board configurations files but used nowhere! 911 912 CONFIG_IDE_RESET - is this is defined, IDE Reset will 913 be performed by calling the function 914 ide_set_reset(int reset) 915 which has to be defined in a board specific file 916 917- ATAPI Support: 918 CONFIG_ATAPI 919 920 Set this to enable ATAPI support. 921 922- LBA48 Support 923 CONFIG_LBA48 924 925 Set this to enable support for disks larger than 137GB 926 Also look at CONFIG_SYS_64BIT_LBA. 927 Whithout these , LBA48 support uses 32bit variables and will 'only' 928 support disks up to 2.1TB. 929 930 CONFIG_SYS_64BIT_LBA: 931 When enabled, makes the IDE subsystem use 64bit sector addresses. 932 Default is 32bit. 933 934- SCSI Support: 935 At the moment only there is only support for the 936 SYM53C8XX SCSI controller; define 937 CONFIG_SCSI_SYM53C8XX to enable it. 938 939 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 940 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 941 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 942 maximum numbers of LUNs, SCSI ID's and target 943 devices. 944 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 945 946- NETWORK Support (PCI): 947 CONFIG_E1000 948 Support for Intel 8254x gigabit chips. 949 950 CONFIG_E1000_FALLBACK_MAC 951 default MAC for empty EEPROM after production. 952 953 CONFIG_EEPRO100 954 Support for Intel 82557/82559/82559ER chips. 955 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 956 write routine for first time initialisation. 957 958 CONFIG_TULIP 959 Support for Digital 2114x chips. 960 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 961 modem chip initialisation (KS8761/QS6611). 962 963 CONFIG_NATSEMI 964 Support for National dp83815 chips. 965 966 CONFIG_NS8382X 967 Support for National dp8382[01] gigabit chips. 968 969- NETWORK Support (other): 970 971 CONFIG_DRIVER_AT91EMAC 972 Support for AT91RM9200 EMAC. 973 974 CONFIG_RMII 975 Define this to use reduced MII inteface 976 977 CONFIG_DRIVER_AT91EMAC_QUIET 978 If this defined, the driver is quiet. 979 The driver doen't show link status messages. 980 981 CONFIG_DRIVER_LAN91C96 982 Support for SMSC's LAN91C96 chips. 983 984 CONFIG_LAN91C96_BASE 985 Define this to hold the physical address 986 of the LAN91C96's I/O space 987 988 CONFIG_LAN91C96_USE_32_BIT 989 Define this to enable 32 bit addressing 990 991 CONFIG_DRIVER_SMC91111 992 Support for SMSC's LAN91C111 chip 993 994 CONFIG_SMC91111_BASE 995 Define this to hold the physical address 996 of the device (I/O space) 997 998 CONFIG_SMC_USE_32_BIT 999 Define this if data bus is 32 bits 1000 1001 CONFIG_SMC_USE_IOFUNCS 1002 Define this to use i/o functions instead of macros 1003 (some hardware wont work with macros) 1004 1005 CONFIG_FTGMAC100 1006 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1007 1008 CONFIG_FTGMAC100_EGIGA 1009 Define this to use GE link update with gigabit PHY. 1010 Define this if FTGMAC100 is connected to gigabit PHY. 1011 If your system has 10/100 PHY only, it might not occur 1012 wrong behavior. Because PHY usually return timeout or 1013 useless data when polling gigabit status and gigabit 1014 control registers. This behavior won't affect the 1015 correctnessof 10/100 link speed update. 1016 1017 CONFIG_SMC911X 1018 Support for SMSC's LAN911x and LAN921x chips 1019 1020 CONFIG_SMC911X_BASE 1021 Define this to hold the physical address 1022 of the device (I/O space) 1023 1024 CONFIG_SMC911X_32_BIT 1025 Define this if data bus is 32 bits 1026 1027 CONFIG_SMC911X_16_BIT 1028 Define this if data bus is 16 bits. If your processor 1029 automatically converts one 32 bit word to two 16 bit 1030 words you may also try CONFIG_SMC911X_32_BIT. 1031 1032 CONFIG_SH_ETHER 1033 Support for Renesas on-chip Ethernet controller 1034 1035 CONFIG_SH_ETHER_USE_PORT 1036 Define the number of ports to be used 1037 1038 CONFIG_SH_ETHER_PHY_ADDR 1039 Define the ETH PHY's address 1040 1041 CONFIG_SH_ETHER_CACHE_WRITEBACK 1042 If this option is set, the driver enables cache flush. 1043 1044- USB Support: 1045 At the moment only the UHCI host controller is 1046 supported (PIP405, MIP405, MPC5200); define 1047 CONFIG_USB_UHCI to enable it. 1048 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1049 and define CONFIG_USB_STORAGE to enable the USB 1050 storage devices. 1051 Note: 1052 Supported are USB Keyboards and USB Floppy drives 1053 (TEAC FD-05PUB). 1054 MPC5200 USB requires additional defines: 1055 CONFIG_USB_CLOCK 1056 for 528 MHz Clock: 0x0001bbbb 1057 CONFIG_PSC3_USB 1058 for USB on PSC3 1059 CONFIG_USB_CONFIG 1060 for differential drivers: 0x00001000 1061 for single ended drivers: 0x00005000 1062 for differential drivers on PSC3: 0x00000100 1063 for single ended drivers on PSC3: 0x00004100 1064 CONFIG_SYS_USB_EVENT_POLL 1065 May be defined to allow interrupt polling 1066 instead of using asynchronous interrupts 1067 1068- USB Device: 1069 Define the below if you wish to use the USB console. 1070 Once firmware is rebuilt from a serial console issue the 1071 command "setenv stdin usbtty; setenv stdout usbtty" and 1072 attach your USB cable. The Unix command "dmesg" should print 1073 it has found a new device. The environment variable usbtty 1074 can be set to gserial or cdc_acm to enable your device to 1075 appear to a USB host as a Linux gserial device or a 1076 Common Device Class Abstract Control Model serial device. 1077 If you select usbtty = gserial you should be able to enumerate 1078 a Linux host by 1079 # modprobe usbserial vendor=0xVendorID product=0xProductID 1080 else if using cdc_acm, simply setting the environment 1081 variable usbtty to be cdc_acm should suffice. The following 1082 might be defined in YourBoardName.h 1083 1084 CONFIG_USB_DEVICE 1085 Define this to build a UDC device 1086 1087 CONFIG_USB_TTY 1088 Define this to have a tty type of device available to 1089 talk to the UDC device 1090 1091 CONFIG_SYS_CONSOLE_IS_IN_ENV 1092 Define this if you want stdin, stdout &/or stderr to 1093 be set to usbtty. 1094 1095 mpc8xx: 1096 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1097 Derive USB clock from external clock "blah" 1098 - CONFIG_SYS_USB_EXTC_CLK 0x02 1099 1100 CONFIG_SYS_USB_BRG_CLK 0xBLAH 1101 Derive USB clock from brgclk 1102 - CONFIG_SYS_USB_BRG_CLK 0x04 1103 1104 If you have a USB-IF assigned VendorID then you may wish to 1105 define your own vendor specific values either in BoardName.h 1106 or directly in usbd_vendor_info.h. If you don't define 1107 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1108 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1109 should pretend to be a Linux device to it's target host. 1110 1111 CONFIG_USBD_MANUFACTURER 1112 Define this string as the name of your company for 1113 - CONFIG_USBD_MANUFACTURER "my company" 1114 1115 CONFIG_USBD_PRODUCT_NAME 1116 Define this string as the name of your product 1117 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1118 1119 CONFIG_USBD_VENDORID 1120 Define this as your assigned Vendor ID from the USB 1121 Implementors Forum. This *must* be a genuine Vendor ID 1122 to avoid polluting the USB namespace. 1123 - CONFIG_USBD_VENDORID 0xFFFF 1124 1125 CONFIG_USBD_PRODUCTID 1126 Define this as the unique Product ID 1127 for your device 1128 - CONFIG_USBD_PRODUCTID 0xFFFF 1129 1130 1131- MMC Support: 1132 The MMC controller on the Intel PXA is supported. To 1133 enable this define CONFIG_MMC. The MMC can be 1134 accessed from the boot prompt by mapping the device 1135 to physical memory similar to flash. Command line is 1136 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1137 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1138 1139 CONFIG_SH_MMCIF 1140 Support for Renesas on-chip MMCIF controller 1141 1142 CONFIG_SH_MMCIF_ADDR 1143 Define the base address of MMCIF registers 1144 1145 CONFIG_SH_MMCIF_CLK 1146 Define the clock frequency for MMCIF 1147 1148- Journaling Flash filesystem support: 1149 CONFIG_JFFS2_NAND, CONFIG_JFFS2_NAND_OFF, CONFIG_JFFS2_NAND_SIZE, 1150 CONFIG_JFFS2_NAND_DEV 1151 Define these for a default partition on a NAND device 1152 1153 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1154 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1155 Define these for a default partition on a NOR device 1156 1157 CONFIG_SYS_JFFS_CUSTOM_PART 1158 Define this to create an own partition. You have to provide a 1159 function struct part_info* jffs2_part_info(int part_num) 1160 1161 If you define only one JFFS2 partition you may also want to 1162 #define CONFIG_SYS_JFFS_SINGLE_PART 1 1163 to disable the command chpart. This is the default when you 1164 have not defined a custom partition 1165 1166- Keyboard Support: 1167 CONFIG_ISA_KEYBOARD 1168 1169 Define this to enable standard (PC-Style) keyboard 1170 support 1171 1172 CONFIG_I8042_KBD 1173 Standard PC keyboard driver with US (is default) and 1174 GERMAN key layout (switch via environment 'keymap=de') support. 1175 Export function i8042_kbd_init, i8042_tstc and i8042_getc 1176 for cfb_console. Supports cursor blinking. 1177 1178- Video support: 1179 CONFIG_VIDEO 1180 1181 Define this to enable video support (for output to 1182 video). 1183 1184 CONFIG_VIDEO_CT69000 1185 1186 Enable Chips & Technologies 69000 Video chip 1187 1188 CONFIG_VIDEO_SMI_LYNXEM 1189 Enable Silicon Motion SMI 712/710/810 Video chip. The 1190 video output is selected via environment 'videoout' 1191 (1 = LCD and 2 = CRT). If videoout is undefined, CRT is 1192 assumed. 1193 1194 For the CT69000 and SMI_LYNXEM drivers, videomode is 1195 selected via environment 'videomode'. Two different ways 1196 are possible: 1197 - "videomode=num" 'num' is a standard LiLo mode numbers. 1198 Following standard modes are supported (* is default): 1199 1200 Colors 640x480 800x600 1024x768 1152x864 1280x1024 1201 -------------+--------------------------------------------- 1202 8 bits | 0x301* 0x303 0x305 0x161 0x307 1203 15 bits | 0x310 0x313 0x316 0x162 0x319 1204 16 bits | 0x311 0x314 0x317 0x163 0x31A 1205 24 bits | 0x312 0x315 0x318 ? 0x31B 1206 -------------+--------------------------------------------- 1207 (i.e. setenv videomode 317; saveenv; reset;) 1208 1209 - "videomode=bootargs" all the video parameters are parsed 1210 from the bootargs. (See drivers/video/videomodes.c) 1211 1212 1213 CONFIG_VIDEO_SED13806 1214 Enable Epson SED13806 driver. This driver supports 8bpp 1215 and 16bpp modes defined by CONFIG_VIDEO_SED13806_8BPP 1216 or CONFIG_VIDEO_SED13806_16BPP 1217 1218 CONFIG_FSL_DIU_FB 1219 Enable the Freescale DIU video driver. Reference boards for 1220 SOCs that have a DIU should define this macro to enable DIU 1221 support, and should also define these other macros: 1222 1223 CONFIG_SYS_DIU_ADDR 1224 CONFIG_VIDEO 1225 CONFIG_CMD_BMP 1226 CONFIG_CFB_CONSOLE 1227 CONFIG_VIDEO_SW_CURSOR 1228 CONFIG_VGA_AS_SINGLE_DEVICE 1229 CONFIG_VIDEO_LOGO 1230 CONFIG_VIDEO_BMP_LOGO 1231 1232 The DIU driver will look for the 'video-mode' environment 1233 variable, and if defined, enable the DIU as a console during 1234 boot. See the documentation file README.video for a 1235 description of this variable. 1236 1237- Keyboard Support: 1238 CONFIG_KEYBOARD 1239 1240 Define this to enable a custom keyboard support. 1241 This simply calls drv_keyboard_init() which must be 1242 defined in your board-specific files. 1243 The only board using this so far is RBC823. 1244 1245- LCD Support: CONFIG_LCD 1246 1247 Define this to enable LCD support (for output to LCD 1248 display); also select one of the supported displays 1249 by defining one of these: 1250 1251 CONFIG_ATMEL_LCD: 1252 1253 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1254 1255 CONFIG_NEC_NL6448AC33: 1256 1257 NEC NL6448AC33-18. Active, color, single scan. 1258 1259 CONFIG_NEC_NL6448BC20 1260 1261 NEC NL6448BC20-08. 6.5", 640x480. 1262 Active, color, single scan. 1263 1264 CONFIG_NEC_NL6448BC33_54 1265 1266 NEC NL6448BC33-54. 10.4", 640x480. 1267 Active, color, single scan. 1268 1269 CONFIG_SHARP_16x9 1270 1271 Sharp 320x240. Active, color, single scan. 1272 It isn't 16x9, and I am not sure what it is. 1273 1274 CONFIG_SHARP_LQ64D341 1275 1276 Sharp LQ64D341 display, 640x480. 1277 Active, color, single scan. 1278 1279 CONFIG_HLD1045 1280 1281 HLD1045 display, 640x480. 1282 Active, color, single scan. 1283 1284 CONFIG_OPTREX_BW 1285 1286 Optrex CBL50840-2 NF-FW 99 22 M5 1287 or 1288 Hitachi LMG6912RPFC-00T 1289 or 1290 Hitachi SP14Q002 1291 1292 320x240. Black & white. 1293 1294 Normally display is black on white background; define 1295 CONFIG_SYS_WHITE_ON_BLACK to get it inverted. 1296 1297- Splash Screen Support: CONFIG_SPLASH_SCREEN 1298 1299 If this option is set, the environment is checked for 1300 a variable "splashimage". If found, the usual display 1301 of logo, copyright and system information on the LCD 1302 is suppressed and the BMP image at the address 1303 specified in "splashimage" is loaded instead. The 1304 console is redirected to the "nulldev", too. This 1305 allows for a "silent" boot where a splash screen is 1306 loaded very quickly after power-on. 1307 1308 CONFIG_SPLASH_SCREEN_ALIGN 1309 1310 If this option is set the splash image can be freely positioned 1311 on the screen. Environment variable "splashpos" specifies the 1312 position as "x,y". If a positive number is given it is used as 1313 number of pixel from left/top. If a negative number is given it 1314 is used as number of pixel from right/bottom. You can also 1315 specify 'm' for centering the image. 1316 1317 Example: 1318 setenv splashpos m,m 1319 => image at center of screen 1320 1321 setenv splashpos 30,20 1322 => image at x = 30 and y = 20 1323 1324 setenv splashpos -10,m 1325 => vertically centered image 1326 at x = dspWidth - bmpWidth - 9 1327 1328- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1329 1330 If this option is set, additionally to standard BMP 1331 images, gzipped BMP images can be displayed via the 1332 splashscreen support or the bmp command. 1333 1334- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1335 1336 If this option is set, 8-bit RLE compressed BMP images 1337 can be displayed via the splashscreen support or the 1338 bmp command. 1339 1340- Compression support: 1341 CONFIG_BZIP2 1342 1343 If this option is set, support for bzip2 compressed 1344 images is included. If not, only uncompressed and gzip 1345 compressed images are supported. 1346 1347 NOTE: the bzip2 algorithm requires a lot of RAM, so 1348 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1349 be at least 4MB. 1350 1351 CONFIG_LZMA 1352 1353 If this option is set, support for lzma compressed 1354 images is included. 1355 1356 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1357 requires an amount of dynamic memory that is given by the 1358 formula: 1359 1360 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1361 1362 Where lc and lp stand for, respectively, Literal context bits 1363 and Literal pos bits. 1364 1365 This value is upper-bounded by 14MB in the worst case. Anyway, 1366 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1367 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1368 a very small buffer. 1369 1370 Use the lzmainfo tool to determinate the lc and lp values and 1371 then calculate the amount of needed dynamic memory (ensuring 1372 the appropriate CONFIG_SYS_MALLOC_LEN value). 1373 1374- MII/PHY support: 1375 CONFIG_PHY_ADDR 1376 1377 The address of PHY on MII bus. 1378 1379 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1380 1381 The clock frequency of the MII bus 1382 1383 CONFIG_PHY_GIGE 1384 1385 If this option is set, support for speed/duplex 1386 detection of gigabit PHY is included. 1387 1388 CONFIG_PHY_RESET_DELAY 1389 1390 Some PHY like Intel LXT971A need extra delay after 1391 reset before any MII register access is possible. 1392 For such PHY, set this option to the usec delay 1393 required. (minimum 300usec for LXT971A) 1394 1395 CONFIG_PHY_CMD_DELAY (ppc4xx) 1396 1397 Some PHY like Intel LXT971A need extra delay after 1398 command issued before MII status register can be read 1399 1400- Ethernet address: 1401 CONFIG_ETHADDR 1402 CONFIG_ETH1ADDR 1403 CONFIG_ETH2ADDR 1404 CONFIG_ETH3ADDR 1405 CONFIG_ETH4ADDR 1406 CONFIG_ETH5ADDR 1407 1408 Define a default value for Ethernet address to use 1409 for the respective Ethernet interface, in case this 1410 is not determined automatically. 1411 1412- IP address: 1413 CONFIG_IPADDR 1414 1415 Define a default value for the IP address to use for 1416 the default Ethernet interface, in case this is not 1417 determined through e.g. bootp. 1418 1419- Server IP address: 1420 CONFIG_SERVERIP 1421 1422 Defines a default value for the IP address of a TFTP 1423 server to contact when using the "tftboot" command. 1424 1425 CONFIG_KEEP_SERVERADDR 1426 1427 Keeps the server's MAC address, in the env 'serveraddr' 1428 for passing to bootargs (like Linux's netconsole option) 1429 1430- Multicast TFTP Mode: 1431 CONFIG_MCAST_TFTP 1432 1433 Defines whether you want to support multicast TFTP as per 1434 rfc-2090; for example to work with atftp. Lets lots of targets 1435 tftp down the same boot image concurrently. Note: the Ethernet 1436 driver in use must provide a function: mcast() to join/leave a 1437 multicast group. 1438 1439- BOOTP Recovery Mode: 1440 CONFIG_BOOTP_RANDOM_DELAY 1441 1442 If you have many targets in a network that try to 1443 boot using BOOTP, you may want to avoid that all 1444 systems send out BOOTP requests at precisely the same 1445 moment (which would happen for instance at recovery 1446 from a power failure, when all systems will try to 1447 boot, thus flooding the BOOTP server. Defining 1448 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1449 inserted before sending out BOOTP requests. The 1450 following delays are inserted then: 1451 1452 1st BOOTP request: delay 0 ... 1 sec 1453 2nd BOOTP request: delay 0 ... 2 sec 1454 3rd BOOTP request: delay 0 ... 4 sec 1455 4th and following 1456 BOOTP requests: delay 0 ... 8 sec 1457 1458- DHCP Advanced Options: 1459 You can fine tune the DHCP functionality by defining 1460 CONFIG_BOOTP_* symbols: 1461 1462 CONFIG_BOOTP_SUBNETMASK 1463 CONFIG_BOOTP_GATEWAY 1464 CONFIG_BOOTP_HOSTNAME 1465 CONFIG_BOOTP_NISDOMAIN 1466 CONFIG_BOOTP_BOOTPATH 1467 CONFIG_BOOTP_BOOTFILESIZE 1468 CONFIG_BOOTP_DNS 1469 CONFIG_BOOTP_DNS2 1470 CONFIG_BOOTP_SEND_HOSTNAME 1471 CONFIG_BOOTP_NTPSERVER 1472 CONFIG_BOOTP_TIMEOFFSET 1473 CONFIG_BOOTP_VENDOREX 1474 1475 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1476 environment variable, not the BOOTP server. 1477 1478 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1479 serverip from a DHCP server, it is possible that more 1480 than one DNS serverip is offered to the client. 1481 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1482 serverip will be stored in the additional environment 1483 variable "dnsip2". The first DNS serverip is always 1484 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1485 is defined. 1486 1487 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1488 to do a dynamic update of a DNS server. To do this, they 1489 need the hostname of the DHCP requester. 1490 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1491 of the "hostname" environment variable is passed as 1492 option 12 to the DHCP server. 1493 1494 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1495 1496 A 32bit value in microseconds for a delay between 1497 receiving a "DHCP Offer" and sending the "DHCP Request". 1498 This fixes a problem with certain DHCP servers that don't 1499 respond 100% of the time to a "DHCP request". E.g. On an 1500 AT91RM9200 processor running at 180MHz, this delay needed 1501 to be *at least* 15,000 usec before a Windows Server 2003 1502 DHCP server would reply 100% of the time. I recommend at 1503 least 50,000 usec to be safe. The alternative is to hope 1504 that one of the retries will be successful but note that 1505 the DHCP timeout and retry process takes a longer than 1506 this delay. 1507 1508 - CDP Options: 1509 CONFIG_CDP_DEVICE_ID 1510 1511 The device id used in CDP trigger frames. 1512 1513 CONFIG_CDP_DEVICE_ID_PREFIX 1514 1515 A two character string which is prefixed to the MAC address 1516 of the device. 1517 1518 CONFIG_CDP_PORT_ID 1519 1520 A printf format string which contains the ascii name of 1521 the port. Normally is set to "eth%d" which sets 1522 eth0 for the first Ethernet, eth1 for the second etc. 1523 1524 CONFIG_CDP_CAPABILITIES 1525 1526 A 32bit integer which indicates the device capabilities; 1527 0x00000010 for a normal host which does not forwards. 1528 1529 CONFIG_CDP_VERSION 1530 1531 An ascii string containing the version of the software. 1532 1533 CONFIG_CDP_PLATFORM 1534 1535 An ascii string containing the name of the platform. 1536 1537 CONFIG_CDP_TRIGGER 1538 1539 A 32bit integer sent on the trigger. 1540 1541 CONFIG_CDP_POWER_CONSUMPTION 1542 1543 A 16bit integer containing the power consumption of the 1544 device in .1 of milliwatts. 1545 1546 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1547 1548 A byte containing the id of the VLAN. 1549 1550- Status LED: CONFIG_STATUS_LED 1551 1552 Several configurations allow to display the current 1553 status using a LED. For instance, the LED will blink 1554 fast while running U-Boot code, stop blinking as 1555 soon as a reply to a BOOTP request was received, and 1556 start blinking slow once the Linux kernel is running 1557 (supported by a status LED driver in the Linux 1558 kernel). Defining CONFIG_STATUS_LED enables this 1559 feature in U-Boot. 1560 1561- CAN Support: CONFIG_CAN_DRIVER 1562 1563 Defining CONFIG_CAN_DRIVER enables CAN driver support 1564 on those systems that support this (optional) 1565 feature, like the TQM8xxL modules. 1566 1567- I2C Support: CONFIG_HARD_I2C | CONFIG_SOFT_I2C 1568 1569 These enable I2C serial bus commands. Defining either of 1570 (but not both of) CONFIG_HARD_I2C or CONFIG_SOFT_I2C will 1571 include the appropriate I2C driver for the selected CPU. 1572 1573 This will allow you to use i2c commands at the u-boot 1574 command line (as long as you set CONFIG_CMD_I2C in 1575 CONFIG_COMMANDS) and communicate with i2c based realtime 1576 clock chips. See common/cmd_i2c.c for a description of the 1577 command line interface. 1578 1579 CONFIG_HARD_I2C selects a hardware I2C controller. 1580 1581 CONFIG_SOFT_I2C configures u-boot to use a software (aka 1582 bit-banging) driver instead of CPM or similar hardware 1583 support for I2C. 1584 1585 There are several other quantities that must also be 1586 defined when you define CONFIG_HARD_I2C or CONFIG_SOFT_I2C. 1587 1588 In both cases you will need to define CONFIG_SYS_I2C_SPEED 1589 to be the frequency (in Hz) at which you wish your i2c bus 1590 to run and CONFIG_SYS_I2C_SLAVE to be the address of this node (ie 1591 the CPU's i2c node address). 1592 1593 Now, the u-boot i2c code for the mpc8xx 1594 (arch/powerpc/cpu/mpc8xx/i2c.c) sets the CPU up as a master node 1595 and so its address should therefore be cleared to 0 (See, 1596 eg, MPC823e User's Manual p.16-473). So, set 1597 CONFIG_SYS_I2C_SLAVE to 0. 1598 1599 CONFIG_SYS_I2C_INIT_MPC5XXX 1600 1601 When a board is reset during an i2c bus transfer 1602 chips might think that the current transfer is still 1603 in progress. Reset the slave devices by sending start 1604 commands until the slave device responds. 1605 1606 That's all that's required for CONFIG_HARD_I2C. 1607 1608 If you use the software i2c interface (CONFIG_SOFT_I2C) 1609 then the following macros need to be defined (examples are 1610 from include/configs/lwmon.h): 1611 1612 I2C_INIT 1613 1614 (Optional). Any commands necessary to enable the I2C 1615 controller or configure ports. 1616 1617 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1618 1619 I2C_PORT 1620 1621 (Only for MPC8260 CPU). The I/O port to use (the code 1622 assumes both bits are on the same port). Valid values 1623 are 0..3 for ports A..D. 1624 1625 I2C_ACTIVE 1626 1627 The code necessary to make the I2C data line active 1628 (driven). If the data line is open collector, this 1629 define can be null. 1630 1631 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1632 1633 I2C_TRISTATE 1634 1635 The code necessary to make the I2C data line tri-stated 1636 (inactive). If the data line is open collector, this 1637 define can be null. 1638 1639 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1640 1641 I2C_READ 1642 1643 Code that returns TRUE if the I2C data line is high, 1644 FALSE if it is low. 1645 1646 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1647 1648 I2C_SDA(bit) 1649 1650 If <bit> is TRUE, sets the I2C data line high. If it 1651 is FALSE, it clears it (low). 1652 1653 eg: #define I2C_SDA(bit) \ 1654 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1655 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1656 1657 I2C_SCL(bit) 1658 1659 If <bit> is TRUE, sets the I2C clock line high. If it 1660 is FALSE, it clears it (low). 1661 1662 eg: #define I2C_SCL(bit) \ 1663 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1664 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1665 1666 I2C_DELAY 1667 1668 This delay is invoked four times per clock cycle so this 1669 controls the rate of data transfer. The data rate thus 1670 is 1 / (I2C_DELAY * 4). Often defined to be something 1671 like: 1672 1673 #define I2C_DELAY udelay(2) 1674 1675 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 1676 1677 If your arch supports the generic GPIO framework (asm/gpio.h), 1678 then you may alternatively define the two GPIOs that are to be 1679 used as SCL / SDA. Any of the previous I2C_xxx macros will 1680 have GPIO-based defaults assigned to them as appropriate. 1681 1682 You should define these to the GPIO value as given directly to 1683 the generic GPIO functions. 1684 1685 CONFIG_SYS_I2C_INIT_BOARD 1686 1687 When a board is reset during an i2c bus transfer 1688 chips might think that the current transfer is still 1689 in progress. On some boards it is possible to access 1690 the i2c SCLK line directly, either by using the 1691 processor pin as a GPIO or by having a second pin 1692 connected to the bus. If this option is defined a 1693 custom i2c_init_board() routine in boards/xxx/board.c 1694 is run early in the boot sequence. 1695 1696 CONFIG_SYS_I2C_BOARD_LATE_INIT 1697 1698 An alternative to CONFIG_SYS_I2C_INIT_BOARD. If this option is 1699 defined a custom i2c_board_late_init() routine in 1700 boards/xxx/board.c is run AFTER the operations in i2c_init() 1701 is completed. This callpoint can be used to unreset i2c bus 1702 using CPU i2c controller register accesses for CPUs whose i2c 1703 controller provide such a method. It is called at the end of 1704 i2c_init() to allow i2c_init operations to setup the i2c bus 1705 controller on the CPU (e.g. setting bus speed & slave address). 1706 1707 CONFIG_I2CFAST (PPC405GP|PPC405EP only) 1708 1709 This option enables configuration of bi_iic_fast[] flags 1710 in u-boot bd_info structure based on u-boot environment 1711 variable "i2cfast". (see also i2cfast) 1712 1713 CONFIG_I2C_MULTI_BUS 1714 1715 This option allows the use of multiple I2C buses, each of which 1716 must have a controller. At any point in time, only one bus is 1717 active. To switch to a different bus, use the 'i2c dev' command. 1718 Note that bus numbering is zero-based. 1719 1720 CONFIG_SYS_I2C_NOPROBES 1721 1722 This option specifies a list of I2C devices that will be skipped 1723 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 1724 is set, specify a list of bus-device pairs. Otherwise, specify 1725 a 1D array of device addresses 1726 1727 e.g. 1728 #undef CONFIG_I2C_MULTI_BUS 1729 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 1730 1731 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1732 1733 #define CONFIG_I2C_MULTI_BUS 1734 #define CONFIG_SYS_I2C_MULTI_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1735 1736 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1737 1738 CONFIG_SYS_SPD_BUS_NUM 1739 1740 If defined, then this indicates the I2C bus number for DDR SPD. 1741 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1742 1743 CONFIG_SYS_RTC_BUS_NUM 1744 1745 If defined, then this indicates the I2C bus number for the RTC. 1746 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1747 1748 CONFIG_SYS_DTT_BUS_NUM 1749 1750 If defined, then this indicates the I2C bus number for the DTT. 1751 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 1752 1753 CONFIG_SYS_I2C_DTT_ADDR: 1754 1755 If defined, specifies the I2C address of the DTT device. 1756 If not defined, then U-Boot uses predefined value for 1757 specified DTT device. 1758 1759 CONFIG_FSL_I2C 1760 1761 Define this option if you want to use Freescale's I2C driver in 1762 drivers/i2c/fsl_i2c.c. 1763 1764 CONFIG_I2C_MUX 1765 1766 Define this option if you have I2C devices reached over 1 .. n 1767 I2C Muxes like the pca9544a. This option addes a new I2C 1768 Command "i2c bus [muxtype:muxaddr:muxchannel]" which adds a 1769 new I2C Bus to the existing I2C Busses. If you select the 1770 new Bus with "i2c dev", u-bbot sends first the commandos for 1771 the muxes to activate this new "bus". 1772 1773 CONFIG_I2C_MULTI_BUS must be also defined, to use this 1774 feature! 1775 1776 Example: 1777 Adding a new I2C Bus reached over 2 pca9544a muxes 1778 The First mux with address 70 and channel 6 1779 The Second mux with address 71 and channel 4 1780 1781 => i2c bus pca9544a:70:6:pca9544a:71:4 1782 1783 Use the "i2c bus" command without parameter, to get a list 1784 of I2C Busses with muxes: 1785 1786 => i2c bus 1787 Busses reached over muxes: 1788 Bus ID: 2 1789 reached over Mux(es): 1790 pca9544a@70 ch: 4 1791 Bus ID: 3 1792 reached over Mux(es): 1793 pca9544a@70 ch: 6 1794 pca9544a@71 ch: 4 1795 => 1796 1797 If you now switch to the new I2C Bus 3 with "i2c dev 3" 1798 u-boot first sends the command to the mux@70 to enable 1799 channel 6, and then the command to the mux@71 to enable 1800 the channel 4. 1801 1802 After that, you can use the "normal" i2c commands as 1803 usual to communicate with your I2C devices behind 1804 the 2 muxes. 1805 1806 This option is actually implemented for the bitbanging 1807 algorithm in common/soft_i2c.c and for the Hardware I2C 1808 Bus on the MPC8260. But it should be not so difficult 1809 to add this option to other architectures. 1810 1811 CONFIG_SOFT_I2C_READ_REPEATED_START 1812 1813 defining this will force the i2c_read() function in 1814 the soft_i2c driver to perform an I2C repeated start 1815 between writing the address pointer and reading the 1816 data. If this define is omitted the default behaviour 1817 of doing a stop-start sequence will be used. Most I2C 1818 devices can use either method, but some require one or 1819 the other. 1820 1821- SPI Support: CONFIG_SPI 1822 1823 Enables SPI driver (so far only tested with 1824 SPI EEPROM, also an instance works with Crystal A/D and 1825 D/As on the SACSng board) 1826 1827 CONFIG_SH_SPI 1828 1829 Enables the driver for SPI controller on SuperH. Currently 1830 only SH7757 is supported. 1831 1832 CONFIG_SPI_X 1833 1834 Enables extended (16-bit) SPI EEPROM addressing. 1835 (symmetrical to CONFIG_I2C_X) 1836 1837 CONFIG_SOFT_SPI 1838 1839 Enables a software (bit-bang) SPI driver rather than 1840 using hardware support. This is a general purpose 1841 driver that only requires three general I/O port pins 1842 (two outputs, one input) to function. If this is 1843 defined, the board configuration must define several 1844 SPI configuration items (port pins to use, etc). For 1845 an example, see include/configs/sacsng.h. 1846 1847 CONFIG_HARD_SPI 1848 1849 Enables a hardware SPI driver for general-purpose reads 1850 and writes. As with CONFIG_SOFT_SPI, the board configuration 1851 must define a list of chip-select function pointers. 1852 Currently supported on some MPC8xxx processors. For an 1853 example, see include/configs/mpc8349emds.h. 1854 1855 CONFIG_MXC_SPI 1856 1857 Enables the driver for the SPI controllers on i.MX and MXC 1858 SoCs. Currently only i.MX31 is supported. 1859 1860- FPGA Support: CONFIG_FPGA 1861 1862 Enables FPGA subsystem. 1863 1864 CONFIG_FPGA_<vendor> 1865 1866 Enables support for specific chip vendors. 1867 (ALTERA, XILINX) 1868 1869 CONFIG_FPGA_<family> 1870 1871 Enables support for FPGA family. 1872 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 1873 1874 CONFIG_FPGA_COUNT 1875 1876 Specify the number of FPGA devices to support. 1877 1878 CONFIG_SYS_FPGA_PROG_FEEDBACK 1879 1880 Enable printing of hash marks during FPGA configuration. 1881 1882 CONFIG_SYS_FPGA_CHECK_BUSY 1883 1884 Enable checks on FPGA configuration interface busy 1885 status by the configuration function. This option 1886 will require a board or device specific function to 1887 be written. 1888 1889 CONFIG_FPGA_DELAY 1890 1891 If defined, a function that provides delays in the FPGA 1892 configuration driver. 1893 1894 CONFIG_SYS_FPGA_CHECK_CTRLC 1895 Allow Control-C to interrupt FPGA configuration 1896 1897 CONFIG_SYS_FPGA_CHECK_ERROR 1898 1899 Check for configuration errors during FPGA bitfile 1900 loading. For example, abort during Virtex II 1901 configuration if the INIT_B line goes low (which 1902 indicated a CRC error). 1903 1904 CONFIG_SYS_FPGA_WAIT_INIT 1905 1906 Maximum time to wait for the INIT_B line to deassert 1907 after PROB_B has been deasserted during a Virtex II 1908 FPGA configuration sequence. The default time is 500 1909 ms. 1910 1911 CONFIG_SYS_FPGA_WAIT_BUSY 1912 1913 Maximum time to wait for BUSY to deassert during 1914 Virtex II FPGA configuration. The default is 5 ms. 1915 1916 CONFIG_SYS_FPGA_WAIT_CONFIG 1917 1918 Time to wait after FPGA configuration. The default is 1919 200 ms. 1920 1921- Configuration Management: 1922 CONFIG_IDENT_STRING 1923 1924 If defined, this string will be added to the U-Boot 1925 version information (U_BOOT_VERSION) 1926 1927- Vendor Parameter Protection: 1928 1929 U-Boot considers the values of the environment 1930 variables "serial#" (Board Serial Number) and 1931 "ethaddr" (Ethernet Address) to be parameters that 1932 are set once by the board vendor / manufacturer, and 1933 protects these variables from casual modification by 1934 the user. Once set, these variables are read-only, 1935 and write or delete attempts are rejected. You can 1936 change this behaviour: 1937 1938 If CONFIG_ENV_OVERWRITE is #defined in your config 1939 file, the write protection for vendor parameters is 1940 completely disabled. Anybody can change or delete 1941 these parameters. 1942 1943 Alternatively, if you #define _both_ CONFIG_ETHADDR 1944 _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 1945 Ethernet address is installed in the environment, 1946 which can be changed exactly ONCE by the user. [The 1947 serial# is unaffected by this, i. e. it remains 1948 read-only.] 1949 1950- Protected RAM: 1951 CONFIG_PRAM 1952 1953 Define this variable to enable the reservation of 1954 "protected RAM", i. e. RAM which is not overwritten 1955 by U-Boot. Define CONFIG_PRAM to hold the number of 1956 kB you want to reserve for pRAM. You can overwrite 1957 this default value by defining an environment 1958 variable "pram" to the number of kB you want to 1959 reserve. Note that the board info structure will 1960 still show the full amount of RAM. If pRAM is 1961 reserved, a new environment variable "mem" will 1962 automatically be defined to hold the amount of 1963 remaining RAM in a form that can be passed as boot 1964 argument to Linux, for instance like that: 1965 1966 setenv bootargs ... mem=\${mem} 1967 saveenv 1968 1969 This way you can tell Linux not to use this memory, 1970 either, which results in a memory region that will 1971 not be affected by reboots. 1972 1973 *WARNING* If your board configuration uses automatic 1974 detection of the RAM size, you must make sure that 1975 this memory test is non-destructive. So far, the 1976 following board configurations are known to be 1977 "pRAM-clean": 1978 1979 ETX094, IVMS8, IVML24, SPD8xx, TQM8xxL, 1980 HERMES, IP860, RPXlite, LWMON, LANTEC, 1981 FLAGADM, TQM8260 1982 1983- Error Recovery: 1984 CONFIG_PANIC_HANG 1985 1986 Define this variable to stop the system in case of a 1987 fatal error, so that you have to reset it manually. 1988 This is probably NOT a good idea for an embedded 1989 system where you want the system to reboot 1990 automatically as fast as possible, but it may be 1991 useful during development since you can try to debug 1992 the conditions that lead to the situation. 1993 1994 CONFIG_NET_RETRY_COUNT 1995 1996 This variable defines the number of retries for 1997 network operations like ARP, RARP, TFTP, or BOOTP 1998 before giving up the operation. If not defined, a 1999 default value of 5 is used. 2000 2001 CONFIG_ARP_TIMEOUT 2002 2003 Timeout waiting for an ARP reply in milliseconds. 2004 2005- Command Interpreter: 2006 CONFIG_AUTO_COMPLETE 2007 2008 Enable auto completion of commands using TAB. 2009 2010 Note that this feature has NOT been implemented yet 2011 for the "hush" shell. 2012 2013 2014 CONFIG_SYS_HUSH_PARSER 2015 2016 Define this variable to enable the "hush" shell (from 2017 Busybox) as command line interpreter, thus enabling 2018 powerful command line syntax like 2019 if...then...else...fi conditionals or `&&' and '||' 2020 constructs ("shell scripts"). 2021 2022 If undefined, you get the old, much simpler behaviour 2023 with a somewhat smaller memory footprint. 2024 2025 2026 CONFIG_SYS_PROMPT_HUSH_PS2 2027 2028 This defines the secondary prompt string, which is 2029 printed when the command interpreter needs more input 2030 to complete a command. Usually "> ". 2031 2032 Note: 2033 2034 In the current implementation, the local variables 2035 space and global environment variables space are 2036 separated. Local variables are those you define by 2037 simply typing `name=value'. To access a local 2038 variable later on, you have write `$name' or 2039 `${name}'; to execute the contents of a variable 2040 directly type `$name' at the command prompt. 2041 2042 Global environment variables are those you use 2043 setenv/printenv to work with. To run a command stored 2044 in such a variable, you need to use the run command, 2045 and you must not use the '$' sign to access them. 2046 2047 To store commands and special characters in a 2048 variable, please use double quotation marks 2049 surrounding the whole text of the variable, instead 2050 of the backslashes before semicolons and special 2051 symbols. 2052 2053- Commandline Editing and History: 2054 CONFIG_CMDLINE_EDITING 2055 2056 Enable editing and History functions for interactive 2057 commandline input operations 2058 2059- Default Environment: 2060 CONFIG_EXTRA_ENV_SETTINGS 2061 2062 Define this to contain any number of null terminated 2063 strings (variable = value pairs) that will be part of 2064 the default environment compiled into the boot image. 2065 2066 For example, place something like this in your 2067 board's config file: 2068 2069 #define CONFIG_EXTRA_ENV_SETTINGS \ 2070 "myvar1=value1\0" \ 2071 "myvar2=value2\0" 2072 2073 Warning: This method is based on knowledge about the 2074 internal format how the environment is stored by the 2075 U-Boot code. This is NOT an official, exported 2076 interface! Although it is unlikely that this format 2077 will change soon, there is no guarantee either. 2078 You better know what you are doing here. 2079 2080 Note: overly (ab)use of the default environment is 2081 discouraged. Make sure to check other ways to preset 2082 the environment like the "source" command or the 2083 boot command first. 2084 2085- DataFlash Support: 2086 CONFIG_HAS_DATAFLASH 2087 2088 Defining this option enables DataFlash features and 2089 allows to read/write in Dataflash via the standard 2090 commands cp, md... 2091 2092- SystemACE Support: 2093 CONFIG_SYSTEMACE 2094 2095 Adding this option adds support for Xilinx SystemACE 2096 chips attached via some sort of local bus. The address 2097 of the chip must also be defined in the 2098 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2099 2100 #define CONFIG_SYSTEMACE 2101 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2102 2103 When SystemACE support is added, the "ace" device type 2104 becomes available to the fat commands, i.e. fatls. 2105 2106- TFTP Fixed UDP Port: 2107 CONFIG_TFTP_PORT 2108 2109 If this is defined, the environment variable tftpsrcp 2110 is used to supply the TFTP UDP source port value. 2111 If tftpsrcp isn't defined, the normal pseudo-random port 2112 number generator is used. 2113 2114 Also, the environment variable tftpdstp is used to supply 2115 the TFTP UDP destination port value. If tftpdstp isn't 2116 defined, the normal port 69 is used. 2117 2118 The purpose for tftpsrcp is to allow a TFTP server to 2119 blindly start the TFTP transfer using the pre-configured 2120 target IP address and UDP port. This has the effect of 2121 "punching through" the (Windows XP) firewall, allowing 2122 the remainder of the TFTP transfer to proceed normally. 2123 A better solution is to properly configure the firewall, 2124 but sometimes that is not allowed. 2125 2126- Show boot progress: 2127 CONFIG_SHOW_BOOT_PROGRESS 2128 2129 Defining this option allows to add some board- 2130 specific code (calling a user-provided function 2131 "show_boot_progress(int)") that enables you to show 2132 the system's boot progress on some display (for 2133 example, some LED's) on your board. At the moment, 2134 the following checkpoints are implemented: 2135 2136Legacy uImage format: 2137 2138 Arg Where When 2139 1 common/cmd_bootm.c before attempting to boot an image 2140 -1 common/cmd_bootm.c Image header has bad magic number 2141 2 common/cmd_bootm.c Image header has correct magic number 2142 -2 common/cmd_bootm.c Image header has bad checksum 2143 3 common/cmd_bootm.c Image header has correct checksum 2144 -3 common/cmd_bootm.c Image data has bad checksum 2145 4 common/cmd_bootm.c Image data has correct checksum 2146 -4 common/cmd_bootm.c Image is for unsupported architecture 2147 5 common/cmd_bootm.c Architecture check OK 2148 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2149 6 common/cmd_bootm.c Image Type check OK 2150 -6 common/cmd_bootm.c gunzip uncompression error 2151 -7 common/cmd_bootm.c Unimplemented compression type 2152 7 common/cmd_bootm.c Uncompression OK 2153 8 common/cmd_bootm.c No uncompress/copy overwrite error 2154 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2155 2156 9 common/image.c Start initial ramdisk verification 2157 -10 common/image.c Ramdisk header has bad magic number 2158 -11 common/image.c Ramdisk header has bad checksum 2159 10 common/image.c Ramdisk header is OK 2160 -12 common/image.c Ramdisk data has bad checksum 2161 11 common/image.c Ramdisk data has correct checksum 2162 12 common/image.c Ramdisk verification complete, start loading 2163 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2164 13 common/image.c Start multifile image verification 2165 14 common/image.c No initial ramdisk, no multifile, continue. 2166 2167 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2168 2169 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2170 -31 post/post.c POST test failed, detected by post_output_backlog() 2171 -32 post/post.c POST test failed, detected by post_run_single() 2172 2173 34 common/cmd_doc.c before loading a Image from a DOC device 2174 -35 common/cmd_doc.c Bad usage of "doc" command 2175 35 common/cmd_doc.c correct usage of "doc" command 2176 -36 common/cmd_doc.c No boot device 2177 36 common/cmd_doc.c correct boot device 2178 -37 common/cmd_doc.c Unknown Chip ID on boot device 2179 37 common/cmd_doc.c correct chip ID found, device available 2180 -38 common/cmd_doc.c Read Error on boot device 2181 38 common/cmd_doc.c reading Image header from DOC device OK 2182 -39 common/cmd_doc.c Image header has bad magic number 2183 39 common/cmd_doc.c Image header has correct magic number 2184 -40 common/cmd_doc.c Error reading Image from DOC device 2185 40 common/cmd_doc.c Image header has correct magic number 2186 41 common/cmd_ide.c before loading a Image from a IDE device 2187 -42 common/cmd_ide.c Bad usage of "ide" command 2188 42 common/cmd_ide.c correct usage of "ide" command 2189 -43 common/cmd_ide.c No boot device 2190 43 common/cmd_ide.c boot device found 2191 -44 common/cmd_ide.c Device not available 2192 44 common/cmd_ide.c Device available 2193 -45 common/cmd_ide.c wrong partition selected 2194 45 common/cmd_ide.c partition selected 2195 -46 common/cmd_ide.c Unknown partition table 2196 46 common/cmd_ide.c valid partition table found 2197 -47 common/cmd_ide.c Invalid partition type 2198 47 common/cmd_ide.c correct partition type 2199 -48 common/cmd_ide.c Error reading Image Header on boot device 2200 48 common/cmd_ide.c reading Image Header from IDE device OK 2201 -49 common/cmd_ide.c Image header has bad magic number 2202 49 common/cmd_ide.c Image header has correct magic number 2203 -50 common/cmd_ide.c Image header has bad checksum 2204 50 common/cmd_ide.c Image header has correct checksum 2205 -51 common/cmd_ide.c Error reading Image from IDE device 2206 51 common/cmd_ide.c reading Image from IDE device OK 2207 52 common/cmd_nand.c before loading a Image from a NAND device 2208 -53 common/cmd_nand.c Bad usage of "nand" command 2209 53 common/cmd_nand.c correct usage of "nand" command 2210 -54 common/cmd_nand.c No boot device 2211 54 common/cmd_nand.c boot device found 2212 -55 common/cmd_nand.c Unknown Chip ID on boot device 2213 55 common/cmd_nand.c correct chip ID found, device available 2214 -56 common/cmd_nand.c Error reading Image Header on boot device 2215 56 common/cmd_nand.c reading Image Header from NAND device OK 2216 -57 common/cmd_nand.c Image header has bad magic number 2217 57 common/cmd_nand.c Image header has correct magic number 2218 -58 common/cmd_nand.c Error reading Image from NAND device 2219 58 common/cmd_nand.c reading Image from NAND device OK 2220 2221 -60 common/env_common.c Environment has a bad CRC, using default 2222 2223 64 net/eth.c starting with Ethernet configuration. 2224 -64 net/eth.c no Ethernet found. 2225 65 net/eth.c Ethernet found. 2226 2227 -80 common/cmd_net.c usage wrong 2228 80 common/cmd_net.c before calling NetLoop() 2229 -81 common/cmd_net.c some error in NetLoop() occurred 2230 81 common/cmd_net.c NetLoop() back without error 2231 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2232 82 common/cmd_net.c trying automatic boot 2233 83 common/cmd_net.c running "source" command 2234 -83 common/cmd_net.c some error in automatic boot or "source" command 2235 84 common/cmd_net.c end without errors 2236 2237FIT uImage format: 2238 2239 Arg Where When 2240 100 common/cmd_bootm.c Kernel FIT Image has correct format 2241 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2242 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2243 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2244 102 common/cmd_bootm.c Kernel unit name specified 2245 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2246 103 common/cmd_bootm.c Found configuration node 2247 104 common/cmd_bootm.c Got kernel subimage node offset 2248 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2249 105 common/cmd_bootm.c Kernel subimage hash verification OK 2250 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2251 106 common/cmd_bootm.c Architecture check OK 2252 -106 common/cmd_bootm.c Kernel subimage has wrong type 2253 107 common/cmd_bootm.c Kernel subimage type OK 2254 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2255 108 common/cmd_bootm.c Got kernel subimage data/size 2256 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2257 -109 common/cmd_bootm.c Can't get kernel subimage type 2258 -110 common/cmd_bootm.c Can't get kernel subimage comp 2259 -111 common/cmd_bootm.c Can't get kernel subimage os 2260 -112 common/cmd_bootm.c Can't get kernel subimage load address 2261 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2262 2263 120 common/image.c Start initial ramdisk verification 2264 -120 common/image.c Ramdisk FIT image has incorrect format 2265 121 common/image.c Ramdisk FIT image has correct format 2266 122 common/image.c No ramdisk subimage unit name, using configuration 2267 -122 common/image.c Can't get configuration for ramdisk subimage 2268 123 common/image.c Ramdisk unit name specified 2269 -124 common/image.c Can't get ramdisk subimage node offset 2270 125 common/image.c Got ramdisk subimage node offset 2271 -125 common/image.c Ramdisk subimage hash verification failed 2272 126 common/image.c Ramdisk subimage hash verification OK 2273 -126 common/image.c Ramdisk subimage for unsupported architecture 2274 127 common/image.c Architecture check OK 2275 -127 common/image.c Can't get ramdisk subimage data/size 2276 128 common/image.c Got ramdisk subimage data/size 2277 129 common/image.c Can't get ramdisk load address 2278 -129 common/image.c Got ramdisk load address 2279 2280 -130 common/cmd_doc.c Incorrect FIT image format 2281 131 common/cmd_doc.c FIT image format OK 2282 2283 -140 common/cmd_ide.c Incorrect FIT image format 2284 141 common/cmd_ide.c FIT image format OK 2285 2286 -150 common/cmd_nand.c Incorrect FIT image format 2287 151 common/cmd_nand.c FIT image format OK 2288 2289- Standalone program support: 2290 CONFIG_STANDALONE_LOAD_ADDR 2291 2292 This option defines a board specific value for the 2293 address where standalone program gets loaded, thus 2294 overwriting the architecture dependent default 2295 settings. 2296 2297- Frame Buffer Address: 2298 CONFIG_FB_ADDR 2299 2300 Define CONFIG_FB_ADDR if you want to use specific 2301 address for frame buffer. 2302 Then system will reserve the frame buffer address to 2303 defined address instead of lcd_setmem (this function 2304 grabs the memory for frame buffer by panel's size). 2305 2306 Please see board_init_f function. 2307 2308- Automatic software updates via TFTP server 2309 CONFIG_UPDATE_TFTP 2310 CONFIG_UPDATE_TFTP_CNT_MAX 2311 CONFIG_UPDATE_TFTP_MSEC_MAX 2312 2313 These options enable and control the auto-update feature; 2314 for a more detailed description refer to doc/README.update. 2315 2316- MTD Support (mtdparts command, UBI support) 2317 CONFIG_MTD_DEVICE 2318 2319 Adds the MTD device infrastructure from the Linux kernel. 2320 Needed for mtdparts command support. 2321 2322 CONFIG_MTD_PARTITIONS 2323 2324 Adds the MTD partitioning infrastructure from the Linux 2325 kernel. Needed for UBI support. 2326 2327- SPL framework 2328 CONFIG_SPL 2329 Enable building of SPL globally. 2330 2331 CONFIG_SPL_TEXT_BASE 2332 TEXT_BASE for linking the SPL binary. 2333 2334 CONFIG_SPL_LDSCRIPT 2335 LDSCRIPT for linking the SPL binary. 2336 2337 CONFIG_SPL_LIBCOMMON_SUPPORT 2338 Support for common/libcommon.o in SPL binary 2339 2340 CONFIG_SPL_LIBDISK_SUPPORT 2341 Support for disk/libdisk.o in SPL binary 2342 2343 CONFIG_SPL_I2C_SUPPORT 2344 Support for drivers/i2c/libi2c.o in SPL binary 2345 2346 CONFIG_SPL_GPIO_SUPPORT 2347 Support for drivers/gpio/libgpio.o in SPL binary 2348 2349 CONFIG_SPL_MMC_SUPPORT 2350 Support for drivers/mmc/libmmc.o in SPL binary 2351 2352 CONFIG_SPL_SERIAL_SUPPORT 2353 Support for drivers/serial/libserial.o in SPL binary 2354 2355 CONFIG_SPL_SPI_FLASH_SUPPORT 2356 Support for drivers/mtd/spi/libspi_flash.o in SPL binary 2357 2358 CONFIG_SPL_SPI_SUPPORT 2359 Support for drivers/spi/libspi.o in SPL binary 2360 2361 CONFIG_SPL_FAT_SUPPORT 2362 Support for fs/fat/libfat.o in SPL binary 2363 2364 CONFIG_SPL_LIBGENERIC_SUPPORT 2365 Support for lib/libgeneric.o in SPL binary 2366 2367Modem Support: 2368-------------- 2369 2370[so far only for SMDK2400 boards] 2371 2372- Modem support enable: 2373 CONFIG_MODEM_SUPPORT 2374 2375- RTS/CTS Flow control enable: 2376 CONFIG_HWFLOW 2377 2378- Modem debug support: 2379 CONFIG_MODEM_SUPPORT_DEBUG 2380 2381 Enables debugging stuff (char screen[1024], dbg()) 2382 for modem support. Useful only with BDI2000. 2383 2384- Interrupt support (PPC): 2385 2386 There are common interrupt_init() and timer_interrupt() 2387 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 2388 for CPU specific initialization. interrupt_init_cpu() 2389 should set decrementer_count to appropriate value. If 2390 CPU resets decrementer automatically after interrupt 2391 (ppc4xx) it should set decrementer_count to zero. 2392 timer_interrupt() calls timer_interrupt_cpu() for CPU 2393 specific handling. If board has watchdog / status_led 2394 / other_activity_monitor it works automatically from 2395 general timer_interrupt(). 2396 2397- General: 2398 2399 In the target system modem support is enabled when a 2400 specific key (key combination) is pressed during 2401 power-on. Otherwise U-Boot will boot normally 2402 (autoboot). The key_pressed() function is called from 2403 board_init(). Currently key_pressed() is a dummy 2404 function, returning 1 and thus enabling modem 2405 initialization. 2406 2407 If there are no modem init strings in the 2408 environment, U-Boot proceed to autoboot; the 2409 previous output (banner, info printfs) will be 2410 suppressed, though. 2411 2412 See also: doc/README.Modem 2413 2414 2415Configuration Settings: 2416----------------------- 2417 2418- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 2419 undefine this when you're short of memory. 2420 2421- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 2422 width of the commands listed in the 'help' command output. 2423 2424- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 2425 prompt for user input. 2426 2427- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 2428 2429- CONFIG_SYS_PBSIZE: Buffer size for Console output 2430 2431- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 2432 2433- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 2434 the application (usually a Linux kernel) when it is 2435 booted 2436 2437- CONFIG_SYS_BAUDRATE_TABLE: 2438 List of legal baudrate settings for this board. 2439 2440- CONFIG_SYS_CONSOLE_INFO_QUIET 2441 Suppress display of console information at boot. 2442 2443- CONFIG_SYS_CONSOLE_IS_IN_ENV 2444 If the board specific function 2445 extern int overwrite_console (void); 2446 returns 1, the stdin, stderr and stdout are switched to the 2447 serial port, else the settings in the environment are used. 2448 2449- CONFIG_SYS_CONSOLE_OVERWRITE_ROUTINE 2450 Enable the call to overwrite_console(). 2451 2452- CONFIG_SYS_CONSOLE_ENV_OVERWRITE 2453 Enable overwrite of previous console environment settings. 2454 2455- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 2456 Begin and End addresses of the area used by the 2457 simple memory test. 2458 2459- CONFIG_SYS_ALT_MEMTEST: 2460 Enable an alternate, more extensive memory test. 2461 2462- CONFIG_SYS_MEMTEST_SCRATCH: 2463 Scratch address used by the alternate memory test 2464 You only need to set this if address zero isn't writeable 2465 2466- CONFIG_SYS_MEM_TOP_HIDE (PPC only): 2467 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 2468 this specified memory area will get subtracted from the top 2469 (end) of RAM and won't get "touched" at all by U-Boot. By 2470 fixing up gd->ram_size the Linux kernel should gets passed 2471 the now "corrected" memory size and won't touch it either. 2472 This should work for arch/ppc and arch/powerpc. Only Linux 2473 board ports in arch/powerpc with bootwrapper support that 2474 recalculate the memory size from the SDRAM controller setup 2475 will have to get fixed in Linux additionally. 2476 2477 This option can be used as a workaround for the 440EPx/GRx 2478 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 2479 be touched. 2480 2481 WARNING: Please make sure that this value is a multiple of 2482 the Linux page size (normally 4k). If this is not the case, 2483 then the end address of the Linux memory will be located at a 2484 non page size aligned address and this could cause major 2485 problems. 2486 2487- CONFIG_SYS_TFTP_LOADADDR: 2488 Default load address for network file downloads 2489 2490- CONFIG_SYS_LOADS_BAUD_CHANGE: 2491 Enable temporary baudrate change while serial download 2492 2493- CONFIG_SYS_SDRAM_BASE: 2494 Physical start address of SDRAM. _Must_ be 0 here. 2495 2496- CONFIG_SYS_MBIO_BASE: 2497 Physical start address of Motherboard I/O (if using a 2498 Cogent motherboard) 2499 2500- CONFIG_SYS_FLASH_BASE: 2501 Physical start address of Flash memory. 2502 2503- CONFIG_SYS_MONITOR_BASE: 2504 Physical start address of boot monitor code (set by 2505 make config files to be same as the text base address 2506 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 2507 CONFIG_SYS_FLASH_BASE when booting from flash. 2508 2509- CONFIG_SYS_MONITOR_LEN: 2510 Size of memory reserved for monitor code, used to 2511 determine _at_compile_time_ (!) if the environment is 2512 embedded within the U-Boot image, or in a separate 2513 flash sector. 2514 2515- CONFIG_SYS_MALLOC_LEN: 2516 Size of DRAM reserved for malloc() use. 2517 2518- CONFIG_SYS_BOOTM_LEN: 2519 Normally compressed uImages are limited to an 2520 uncompressed size of 8 MBytes. If this is not enough, 2521 you can define CONFIG_SYS_BOOTM_LEN in your board config file 2522 to adjust this setting to your needs. 2523 2524- CONFIG_SYS_BOOTMAPSZ: 2525 Maximum size of memory mapped by the startup code of 2526 the Linux kernel; all data that must be processed by 2527 the Linux kernel (bd_info, boot arguments, FDT blob if 2528 used) must be put below this limit, unless "bootm_low" 2529 enviroment variable is defined and non-zero. In such case 2530 all data for the Linux kernel must be between "bootm_low" 2531 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 2532 variable "bootm_mapsize" will override the value of 2533 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 2534 then the value in "bootm_size" will be used instead. 2535 2536- CONFIG_SYS_BOOT_RAMDISK_HIGH: 2537 Enable initrd_high functionality. If defined then the 2538 initrd_high feature is enabled and the bootm ramdisk subcommand 2539 is enabled. 2540 2541- CONFIG_SYS_BOOT_GET_CMDLINE: 2542 Enables allocating and saving kernel cmdline in space between 2543 "bootm_low" and "bootm_low" + BOOTMAPSZ. 2544 2545- CONFIG_SYS_BOOT_GET_KBD: 2546 Enables allocating and saving a kernel copy of the bd_info in 2547 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 2548 2549- CONFIG_SYS_MAX_FLASH_BANKS: 2550 Max number of Flash memory banks 2551 2552- CONFIG_SYS_MAX_FLASH_SECT: 2553 Max number of sectors on a Flash chip 2554 2555- CONFIG_SYS_FLASH_ERASE_TOUT: 2556 Timeout for Flash erase operations (in ms) 2557 2558- CONFIG_SYS_FLASH_WRITE_TOUT: 2559 Timeout for Flash write operations (in ms) 2560 2561- CONFIG_SYS_FLASH_LOCK_TOUT 2562 Timeout for Flash set sector lock bit operation (in ms) 2563 2564- CONFIG_SYS_FLASH_UNLOCK_TOUT 2565 Timeout for Flash clear lock bits operation (in ms) 2566 2567- CONFIG_SYS_FLASH_PROTECTION 2568 If defined, hardware flash sectors protection is used 2569 instead of U-Boot software protection. 2570 2571- CONFIG_SYS_DIRECT_FLASH_TFTP: 2572 2573 Enable TFTP transfers directly to flash memory; 2574 without this option such a download has to be 2575 performed in two steps: (1) download to RAM, and (2) 2576 copy from RAM to flash. 2577 2578 The two-step approach is usually more reliable, since 2579 you can check if the download worked before you erase 2580 the flash, but in some situations (when system RAM is 2581 too limited to allow for a temporary copy of the 2582 downloaded image) this option may be very useful. 2583 2584- CONFIG_SYS_FLASH_CFI: 2585 Define if the flash driver uses extra elements in the 2586 common flash structure for storing flash geometry. 2587 2588- CONFIG_FLASH_CFI_DRIVER 2589 This option also enables the building of the cfi_flash driver 2590 in the drivers directory 2591 2592- CONFIG_FLASH_CFI_MTD 2593 This option enables the building of the cfi_mtd driver 2594 in the drivers directory. The driver exports CFI flash 2595 to the MTD layer. 2596 2597- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 2598 Use buffered writes to flash. 2599 2600- CONFIG_FLASH_SPANSION_S29WS_N 2601 s29ws-n MirrorBit flash has non-standard addresses for buffered 2602 write commands. 2603 2604- CONFIG_SYS_FLASH_QUIET_TEST 2605 If this option is defined, the common CFI flash doesn't 2606 print it's warning upon not recognized FLASH banks. This 2607 is useful, if some of the configured banks are only 2608 optionally available. 2609 2610- CONFIG_FLASH_SHOW_PROGRESS 2611 If defined (must be an integer), print out countdown 2612 digits and dots. Recommended value: 45 (9..1) for 80 2613 column displays, 15 (3..1) for 40 column displays. 2614 2615- CONFIG_SYS_RX_ETH_BUFFER: 2616 Defines the number of Ethernet receive buffers. On some 2617 Ethernet controllers it is recommended to set this value 2618 to 8 or even higher (EEPRO100 or 405 EMAC), since all 2619 buffers can be full shortly after enabling the interface 2620 on high Ethernet traffic. 2621 Defaults to 4 if not defined. 2622 2623- CONFIG_ENV_MAX_ENTRIES 2624 2625 Maximum number of entries in the hash table that is used 2626 internally to store the environment settings. The default 2627 setting is supposed to be generous and should work in most 2628 cases. This setting can be used to tune behaviour; see 2629 lib/hashtable.c for details. 2630 2631The following definitions that deal with the placement and management 2632of environment data (variable area); in general, we support the 2633following configurations: 2634 2635- CONFIG_BUILD_ENVCRC: 2636 2637 Builds up envcrc with the target environment so that external utils 2638 may easily extract it and embed it in final U-Boot images. 2639 2640- CONFIG_ENV_IS_IN_FLASH: 2641 2642 Define this if the environment is in flash memory. 2643 2644 a) The environment occupies one whole flash sector, which is 2645 "embedded" in the text segment with the U-Boot code. This 2646 happens usually with "bottom boot sector" or "top boot 2647 sector" type flash chips, which have several smaller 2648 sectors at the start or the end. For instance, such a 2649 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 2650 such a case you would place the environment in one of the 2651 4 kB sectors - with U-Boot code before and after it. With 2652 "top boot sector" type flash chips, you would put the 2653 environment in one of the last sectors, leaving a gap 2654 between U-Boot and the environment. 2655 2656 - CONFIG_ENV_OFFSET: 2657 2658 Offset of environment data (variable area) to the 2659 beginning of flash memory; for instance, with bottom boot 2660 type flash chips the second sector can be used: the offset 2661 for this sector is given here. 2662 2663 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 2664 2665 - CONFIG_ENV_ADDR: 2666 2667 This is just another way to specify the start address of 2668 the flash sector containing the environment (instead of 2669 CONFIG_ENV_OFFSET). 2670 2671 - CONFIG_ENV_SECT_SIZE: 2672 2673 Size of the sector containing the environment. 2674 2675 2676 b) Sometimes flash chips have few, equal sized, BIG sectors. 2677 In such a case you don't want to spend a whole sector for 2678 the environment. 2679 2680 - CONFIG_ENV_SIZE: 2681 2682 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 2683 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 2684 of this flash sector for the environment. This saves 2685 memory for the RAM copy of the environment. 2686 2687 It may also save flash memory if you decide to use this 2688 when your environment is "embedded" within U-Boot code, 2689 since then the remainder of the flash sector could be used 2690 for U-Boot code. It should be pointed out that this is 2691 STRONGLY DISCOURAGED from a robustness point of view: 2692 updating the environment in flash makes it always 2693 necessary to erase the WHOLE sector. If something goes 2694 wrong before the contents has been restored from a copy in 2695 RAM, your target system will be dead. 2696 2697 - CONFIG_ENV_ADDR_REDUND 2698 CONFIG_ENV_SIZE_REDUND 2699 2700 These settings describe a second storage area used to hold 2701 a redundant copy of the environment data, so that there is 2702 a valid backup copy in case there is a power failure during 2703 a "saveenv" operation. 2704 2705BE CAREFUL! Any changes to the flash layout, and some changes to the 2706source code will make it necessary to adapt <board>/u-boot.lds* 2707accordingly! 2708 2709 2710- CONFIG_ENV_IS_IN_NVRAM: 2711 2712 Define this if you have some non-volatile memory device 2713 (NVRAM, battery buffered SRAM) which you want to use for the 2714 environment. 2715 2716 - CONFIG_ENV_ADDR: 2717 - CONFIG_ENV_SIZE: 2718 2719 These two #defines are used to determine the memory area you 2720 want to use for environment. It is assumed that this memory 2721 can just be read and written to, without any special 2722 provision. 2723 2724BE CAREFUL! The first access to the environment happens quite early 2725in U-Boot initalization (when we try to get the setting of for the 2726console baudrate). You *MUST* have mapped your NVRAM area then, or 2727U-Boot will hang. 2728 2729Please note that even with NVRAM we still use a copy of the 2730environment in RAM: we could work on NVRAM directly, but we want to 2731keep settings there always unmodified except somebody uses "saveenv" 2732to save the current settings. 2733 2734 2735- CONFIG_ENV_IS_IN_EEPROM: 2736 2737 Use this if you have an EEPROM or similar serial access 2738 device and a driver for it. 2739 2740 - CONFIG_ENV_OFFSET: 2741 - CONFIG_ENV_SIZE: 2742 2743 These two #defines specify the offset and size of the 2744 environment area within the total memory of your EEPROM. 2745 2746 - CONFIG_SYS_I2C_EEPROM_ADDR: 2747 If defined, specified the chip address of the EEPROM device. 2748 The default address is zero. 2749 2750 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 2751 If defined, the number of bits used to address bytes in a 2752 single page in the EEPROM device. A 64 byte page, for example 2753 would require six bits. 2754 2755 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 2756 If defined, the number of milliseconds to delay between 2757 page writes. The default is zero milliseconds. 2758 2759 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 2760 The length in bytes of the EEPROM memory array address. Note 2761 that this is NOT the chip address length! 2762 2763 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 2764 EEPROM chips that implement "address overflow" are ones 2765 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 2766 address and the extra bits end up in the "chip address" bit 2767 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 2768 byte chips. 2769 2770 Note that we consider the length of the address field to 2771 still be one byte because the extra address bits are hidden 2772 in the chip address. 2773 2774 - CONFIG_SYS_EEPROM_SIZE: 2775 The size in bytes of the EEPROM device. 2776 2777 - CONFIG_ENV_EEPROM_IS_ON_I2C 2778 define this, if you have I2C and SPI activated, and your 2779 EEPROM, which holds the environment, is on the I2C bus. 2780 2781 - CONFIG_I2C_ENV_EEPROM_BUS 2782 if you have an Environment on an EEPROM reached over 2783 I2C muxes, you can define here, how to reach this 2784 EEPROM. For example: 2785 2786 #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0" 2787 2788 EEPROM which holds the environment, is reached over 2789 a pca9547 i2c mux with address 0x70, channel 3. 2790 2791- CONFIG_ENV_IS_IN_DATAFLASH: 2792 2793 Define this if you have a DataFlash memory device which you 2794 want to use for the environment. 2795 2796 - CONFIG_ENV_OFFSET: 2797 - CONFIG_ENV_ADDR: 2798 - CONFIG_ENV_SIZE: 2799 2800 These three #defines specify the offset and size of the 2801 environment area within the total memory of your DataFlash placed 2802 at the specified address. 2803 2804- CONFIG_ENV_IS_IN_NAND: 2805 2806 Define this if you have a NAND device which you want to use 2807 for the environment. 2808 2809 - CONFIG_ENV_OFFSET: 2810 - CONFIG_ENV_SIZE: 2811 2812 These two #defines specify the offset and size of the environment 2813 area within the first NAND device. CONFIG_ENV_OFFSET must be 2814 aligned to an erase block boundary. 2815 2816 - CONFIG_ENV_OFFSET_REDUND (optional): 2817 2818 This setting describes a second storage area of CONFIG_ENV_SIZE 2819 size used to hold a redundant copy of the environment data, so 2820 that there is a valid backup copy in case there is a power failure 2821 during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be 2822 aligned to an erase block boundary. 2823 2824 - CONFIG_ENV_RANGE (optional): 2825 2826 Specifies the length of the region in which the environment 2827 can be written. This should be a multiple of the NAND device's 2828 block size. Specifying a range with more erase blocks than 2829 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 2830 the range to be avoided. 2831 2832 - CONFIG_ENV_OFFSET_OOB (optional): 2833 2834 Enables support for dynamically retrieving the offset of the 2835 environment from block zero's out-of-band data. The 2836 "nand env.oob" command can be used to record this offset. 2837 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 2838 using CONFIG_ENV_OFFSET_OOB. 2839 2840- CONFIG_NAND_ENV_DST 2841 2842 Defines address in RAM to which the nand_spl code should copy the 2843 environment. If redundant environment is used, it will be copied to 2844 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 2845 2846- CONFIG_SYS_SPI_INIT_OFFSET 2847 2848 Defines offset to the initial SPI buffer area in DPRAM. The 2849 area is used at an early stage (ROM part) if the environment 2850 is configured to reside in the SPI EEPROM: We need a 520 byte 2851 scratch DPRAM area. It is used between the two initialization 2852 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 2853 to be a good choice since it makes it far enough from the 2854 start of the data area as well as from the stack pointer. 2855 2856Please note that the environment is read-only until the monitor 2857has been relocated to RAM and a RAM copy of the environment has been 2858created; also, when using EEPROM you will have to use getenv_f() 2859until then to read environment variables. 2860 2861The environment is protected by a CRC32 checksum. Before the monitor 2862is relocated into RAM, as a result of a bad CRC you will be working 2863with the compiled-in default environment - *silently*!!! [This is 2864necessary, because the first environment variable we need is the 2865"baudrate" setting for the console - if we have a bad CRC, we don't 2866have any device yet where we could complain.] 2867 2868Note: once the monitor has been relocated, then it will complain if 2869the default environment is used; a new CRC is computed as soon as you 2870use the "saveenv" command to store a valid environment. 2871 2872- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 2873 Echo the inverted Ethernet link state to the fault LED. 2874 2875 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 2876 also needs to be defined. 2877 2878- CONFIG_SYS_FAULT_MII_ADDR: 2879 MII address of the PHY to check for the Ethernet link state. 2880 2881- CONFIG_NS16550_MIN_FUNCTIONS: 2882 Define this if you desire to only have use of the NS16550_init 2883 and NS16550_putc functions for the serial driver located at 2884 drivers/serial/ns16550.c. This option is useful for saving 2885 space for already greatly restricted images, including but not 2886 limited to NAND_SPL configurations. 2887 2888Low Level (hardware related) configuration options: 2889--------------------------------------------------- 2890 2891- CONFIG_SYS_CACHELINE_SIZE: 2892 Cache Line Size of the CPU. 2893 2894- CONFIG_SYS_DEFAULT_IMMR: 2895 Default address of the IMMR after system reset. 2896 2897 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 2898 and RPXsuper) to be able to adjust the position of 2899 the IMMR register after a reset. 2900 2901- CONFIG_SYS_CCSRBAR_DEFAULT: 2902 Default (power-on reset) physical address of CCSR on Freescale 2903 PowerPC SOCs. 2904 2905- CONFIG_SYS_CCSRBAR: 2906 Virtual address of CCSR. On a 32-bit build, this is typically 2907 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 2908 2909 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 2910 for cross-platform code that uses that macro instead. 2911 2912- CONFIG_SYS_CCSRBAR_PHYS: 2913 Physical address of CCSR. CCSR can be relocated to a new 2914 physical address, if desired. In this case, this macro should 2915 be set to that address. Otherwise, it should be set to the 2916 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 2917 is typically relocated on 36-bit builds. It is recommended 2918 that this macro be defined via the _HIGH and _LOW macros: 2919 2920 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 2921 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 2922 2923- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 2924 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 2925 either 0 (32-bit build) or 0xF (36-bit build). This macro is 2926 used in assembly code, so it must not contain typecasts or 2927 integer size suffixes (e.g. "ULL"). 2928 2929- CONFIG_SYS_CCSRBAR_PHYS_LOW: 2930 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 2931 used in assembly code, so it must not contain typecasts or 2932 integer size suffixes (e.g. "ULL"). 2933 2934- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 2935 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 2936 forced to a value that ensures that CCSR is not relocated. 2937 2938- Floppy Disk Support: 2939 CONFIG_SYS_FDC_DRIVE_NUMBER 2940 2941 the default drive number (default value 0) 2942 2943 CONFIG_SYS_ISA_IO_STRIDE 2944 2945 defines the spacing between FDC chipset registers 2946 (default value 1) 2947 2948 CONFIG_SYS_ISA_IO_OFFSET 2949 2950 defines the offset of register from address. It 2951 depends on which part of the data bus is connected to 2952 the FDC chipset. (default value 0) 2953 2954 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 2955 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 2956 default value. 2957 2958 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 2959 fdc_hw_init() is called at the beginning of the FDC 2960 setup. fdc_hw_init() must be provided by the board 2961 source code. It is used to make hardware dependant 2962 initializations. 2963 2964- CONFIG_IDE_AHB: 2965 Most IDE controllers were designed to be connected with PCI 2966 interface. Only few of them were designed for AHB interface. 2967 When software is doing ATA command and data transfer to 2968 IDE devices through IDE-AHB controller, some additional 2969 registers accessing to these kind of IDE-AHB controller 2970 is requierd. 2971 2972- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 2973 DO NOT CHANGE unless you know exactly what you're 2974 doing! (11-4) [MPC8xx/82xx systems only] 2975 2976- CONFIG_SYS_INIT_RAM_ADDR: 2977 2978 Start address of memory area that can be used for 2979 initial data and stack; please note that this must be 2980 writable memory that is working WITHOUT special 2981 initialization, i. e. you CANNOT use normal RAM which 2982 will become available only after programming the 2983 memory controller and running certain initialization 2984 sequences. 2985 2986 U-Boot uses the following memory types: 2987 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 2988 - MPC824X: data cache 2989 - PPC4xx: data cache 2990 2991- CONFIG_SYS_GBL_DATA_OFFSET: 2992 2993 Offset of the initial data structure in the memory 2994 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 2995 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 2996 data is located at the end of the available space 2997 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 2998 CONFIG_SYS_INIT_DATA_SIZE), and the initial stack is just 2999 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 3000 CONFIG_SYS_GBL_DATA_OFFSET) downward. 3001 3002 Note: 3003 On the MPC824X (or other systems that use the data 3004 cache for initial memory) the address chosen for 3005 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 3006 point to an otherwise UNUSED address space between 3007 the top of RAM and the start of the PCI space. 3008 3009- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 3010 3011- CONFIG_SYS_SYPCR: System Protection Control (11-9) 3012 3013- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 3014 3015- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 3016 3017- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 3018 3019- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 3020 3021- CONFIG_SYS_OR_TIMING_SDRAM: 3022 SDRAM timing 3023 3024- CONFIG_SYS_MAMR_PTA: 3025 periodic timer for refresh 3026 3027- CONFIG_SYS_DER: Debug Event Register (37-47) 3028 3029- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 3030 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 3031 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 3032 CONFIG_SYS_BR1_PRELIM: 3033 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 3034 3035- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 3036 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 3037 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 3038 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 3039 3040- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 3041 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 3042 Machine Mode Register and Memory Periodic Timer 3043 Prescaler definitions (SDRAM timing) 3044 3045- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 3046 enable I2C microcode relocation patch (MPC8xx); 3047 define relocation offset in DPRAM [DSP2] 3048 3049- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 3050 enable SMC microcode relocation patch (MPC8xx); 3051 define relocation offset in DPRAM [SMC1] 3052 3053- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 3054 enable SPI microcode relocation patch (MPC8xx); 3055 define relocation offset in DPRAM [SCC4] 3056 3057- CONFIG_SYS_USE_OSCCLK: 3058 Use OSCM clock mode on MBX8xx board. Be careful, 3059 wrong setting might damage your board. Read 3060 doc/README.MBX before setting this variable! 3061 3062- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 3063 Offset of the bootmode word in DPRAM used by post 3064 (Power On Self Tests). This definition overrides 3065 #define'd default value in commproc.h resp. 3066 cpm_8260.h. 3067 3068- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 3069 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 3070 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 3071 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 3072 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 3073 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 3074 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 3075 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 3076 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 3077 3078- CONFIG_PCI_DISABLE_PCIE: 3079 Disable PCI-Express on systems where it is supported but not 3080 required. 3081 3082- CONFIG_SYS_SRIO: 3083 Chip has SRIO or not 3084 3085- CONFIG_SRIO1: 3086 Board has SRIO 1 port available 3087 3088- CONFIG_SRIO2: 3089 Board has SRIO 2 port available 3090 3091- CONFIG_SYS_SRIOn_MEM_VIRT: 3092 Virtual Address of SRIO port 'n' memory region 3093 3094- CONFIG_SYS_SRIOn_MEM_PHYS: 3095 Physical Address of SRIO port 'n' memory region 3096 3097- CONFIG_SYS_SRIOn_MEM_SIZE: 3098 Size of SRIO port 'n' memory region 3099 3100- CONFIG_SYS_NDFC_16 3101 Defined to tell the NDFC that the NAND chip is using a 3102 16 bit bus. 3103 3104- CONFIG_SYS_NDFC_EBC0_CFG 3105 Sets the EBC0_CFG register for the NDFC. If not defined 3106 a default value will be used. 3107 3108- CONFIG_SPD_EEPROM 3109 Get DDR timing information from an I2C EEPROM. Common 3110 with pluggable memory modules such as SODIMMs 3111 3112 SPD_EEPROM_ADDRESS 3113 I2C address of the SPD EEPROM 3114 3115- CONFIG_SYS_SPD_BUS_NUM 3116 If SPD EEPROM is on an I2C bus other than the first 3117 one, specify here. Note that the value must resolve 3118 to something your driver can deal with. 3119 3120- CONFIG_SYS_DDR_RAW_TIMING 3121 Get DDR timing information from other than SPD. Common with 3122 soldered DDR chips onboard without SPD. DDR raw timing 3123 parameters are extracted from datasheet and hard-coded into 3124 header files or board specific files. 3125 3126- CONFIG_FSL_DDR_INTERACTIVE 3127 Enable interactive DDR debugging. See doc/README.fsl-ddr. 3128 3129- CONFIG_SYS_83XX_DDR_USES_CS0 3130 Only for 83xx systems. If specified, then DDR should 3131 be configured using CS0 and CS1 instead of CS2 and CS3. 3132 3133- CONFIG_ETHER_ON_FEC[12] 3134 Define to enable FEC[12] on a 8xx series processor. 3135 3136- CONFIG_FEC[12]_PHY 3137 Define to the hardcoded PHY address which corresponds 3138 to the given FEC; i. e. 3139 #define CONFIG_FEC1_PHY 4 3140 means that the PHY with address 4 is connected to FEC1 3141 3142 When set to -1, means to probe for first available. 3143 3144- CONFIG_FEC[12]_PHY_NORXERR 3145 The PHY does not have a RXERR line (RMII only). 3146 (so program the FEC to ignore it). 3147 3148- CONFIG_RMII 3149 Enable RMII mode for all FECs. 3150 Note that this is a global option, we can't 3151 have one FEC in standard MII mode and another in RMII mode. 3152 3153- CONFIG_CRC32_VERIFY 3154 Add a verify option to the crc32 command. 3155 The syntax is: 3156 3157 => crc32 -v <address> <count> <crc32> 3158 3159 Where address/count indicate a memory area 3160 and crc32 is the correct crc32 which the 3161 area should have. 3162 3163- CONFIG_LOOPW 3164 Add the "loopw" memory command. This only takes effect if 3165 the memory commands are activated globally (CONFIG_CMD_MEM). 3166 3167- CONFIG_MX_CYCLIC 3168 Add the "mdc" and "mwc" memory commands. These are cyclic 3169 "md/mw" commands. 3170 Examples: 3171 3172 => mdc.b 10 4 500 3173 This command will print 4 bytes (10,11,12,13) each 500 ms. 3174 3175 => mwc.l 100 12345678 10 3176 This command will write 12345678 to address 100 all 10 ms. 3177 3178 This only takes effect if the memory commands are activated 3179 globally (CONFIG_CMD_MEM). 3180 3181- CONFIG_SKIP_LOWLEVEL_INIT 3182 [ARM, NDS32, MIPS only] If this variable is defined, then certain 3183 low level initializations (like setting up the memory 3184 controller) are omitted and/or U-Boot does not 3185 relocate itself into RAM. 3186 3187 Normally this variable MUST NOT be defined. The only 3188 exception is when U-Boot is loaded (to RAM) by some 3189 other boot loader or by a debugger which performs 3190 these initializations itself. 3191 3192- CONFIG_SPL_BUILD 3193 Modifies the behaviour of start.S when compiling a loader 3194 that is executed before the actual U-Boot. E.g. when 3195 compiling a NAND SPL. 3196 3197- CONFIG_USE_ARCH_MEMCPY 3198 CONFIG_USE_ARCH_MEMSET 3199 If these options are used a optimized version of memcpy/memset will 3200 be used if available. These functions may be faster under some 3201 conditions but may increase the binary size. 3202 3203Building the Software: 3204====================== 3205 3206Building U-Boot has been tested in several native build environments 3207and in many different cross environments. Of course we cannot support 3208all possibly existing versions of cross development tools in all 3209(potentially obsolete) versions. In case of tool chain problems we 3210recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 3211which is extensively used to build and test U-Boot. 3212 3213If you are not using a native environment, it is assumed that you 3214have GNU cross compiling tools available in your path. In this case, 3215you must set the environment variable CROSS_COMPILE in your shell. 3216Note that no changes to the Makefile or any other source files are 3217necessary. For example using the ELDK on a 4xx CPU, please enter: 3218 3219 $ CROSS_COMPILE=ppc_4xx- 3220 $ export CROSS_COMPILE 3221 3222Note: If you wish to generate Windows versions of the utilities in 3223 the tools directory you can use the MinGW toolchain 3224 (http://www.mingw.org). Set your HOST tools to the MinGW 3225 toolchain and execute 'make tools'. For example: 3226 3227 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 3228 3229 Binaries such as tools/mkimage.exe will be created which can 3230 be executed on computers running Windows. 3231 3232U-Boot is intended to be simple to build. After installing the 3233sources you must configure U-Boot for one specific board type. This 3234is done by typing: 3235 3236 make NAME_config 3237 3238where "NAME_config" is the name of one of the existing configu- 3239rations; see the main Makefile for supported names. 3240 3241Note: for some board special configuration names may exist; check if 3242 additional information is available from the board vendor; for 3243 instance, the TQM823L systems are available without (standard) 3244 or with LCD support. You can select such additional "features" 3245 when choosing the configuration, i. e. 3246 3247 make TQM823L_config 3248 - will configure for a plain TQM823L, i. e. no LCD support 3249 3250 make TQM823L_LCD_config 3251 - will configure for a TQM823L with U-Boot console on LCD 3252 3253 etc. 3254 3255 3256Finally, type "make all", and you should get some working U-Boot 3257images ready for download to / installation on your system: 3258 3259- "u-boot.bin" is a raw binary image 3260- "u-boot" is an image in ELF binary format 3261- "u-boot.srec" is in Motorola S-Record format 3262 3263By default the build is performed locally and the objects are saved 3264in the source directory. One of the two methods can be used to change 3265this behavior and build U-Boot to some external directory: 3266 32671. Add O= to the make command line invocations: 3268 3269 make O=/tmp/build distclean 3270 make O=/tmp/build NAME_config 3271 make O=/tmp/build all 3272 32732. Set environment variable BUILD_DIR to point to the desired location: 3274 3275 export BUILD_DIR=/tmp/build 3276 make distclean 3277 make NAME_config 3278 make all 3279 3280Note that the command line "O=" setting overrides the BUILD_DIR environment 3281variable. 3282 3283 3284Please be aware that the Makefiles assume you are using GNU make, so 3285for instance on NetBSD you might need to use "gmake" instead of 3286native "make". 3287 3288 3289If the system board that you have is not listed, then you will need 3290to port U-Boot to your hardware platform. To do this, follow these 3291steps: 3292 32931. Add a new configuration option for your board to the toplevel 3294 "Makefile" and to the "MAKEALL" script, using the existing 3295 entries as examples. Note that here and at many other places 3296 boards and other names are listed in alphabetical sort order. Please 3297 keep this order. 32982. Create a new directory to hold your board specific code. Add any 3299 files you need. In your board directory, you will need at least 3300 the "Makefile", a "<board>.c", "flash.c" and "u-boot.lds". 33013. Create a new configuration file "include/configs/<board>.h" for 3302 your board 33033. If you're porting U-Boot to a new CPU, then also create a new 3304 directory to hold your CPU specific code. Add any files you need. 33054. Run "make <board>_config" with your new name. 33065. Type "make", and you should get a working "u-boot.srec" file 3307 to be installed on your target system. 33086. Debug and solve any problems that might arise. 3309 [Of course, this last step is much harder than it sounds.] 3310 3311 3312Testing of U-Boot Modifications, Ports to New Hardware, etc.: 3313============================================================== 3314 3315If you have modified U-Boot sources (for instance added a new board 3316or support for new devices, a new CPU, etc.) you are expected to 3317provide feedback to the other developers. The feedback normally takes 3318the form of a "patch", i. e. a context diff against a certain (latest 3319official or latest in the git repository) version of U-Boot sources. 3320 3321But before you submit such a patch, please verify that your modifi- 3322cation did not break existing code. At least make sure that *ALL* of 3323the supported boards compile WITHOUT ANY compiler warnings. To do so, 3324just run the "MAKEALL" script, which will configure and build U-Boot 3325for ALL supported system. Be warned, this will take a while. You can 3326select which (cross) compiler to use by passing a `CROSS_COMPILE' 3327environment variable to the script, i. e. to use the ELDK cross tools 3328you can type 3329 3330 CROSS_COMPILE=ppc_8xx- MAKEALL 3331 3332or to build on a native PowerPC system you can type 3333 3334 CROSS_COMPILE=' ' MAKEALL 3335 3336When using the MAKEALL script, the default behaviour is to build 3337U-Boot in the source directory. This location can be changed by 3338setting the BUILD_DIR environment variable. Also, for each target 3339built, the MAKEALL script saves two log files (<target>.ERR and 3340<target>.MAKEALL) in the <source dir>/LOG directory. This default 3341location can be changed by setting the MAKEALL_LOGDIR environment 3342variable. For example: 3343 3344 export BUILD_DIR=/tmp/build 3345 export MAKEALL_LOGDIR=/tmp/log 3346 CROSS_COMPILE=ppc_8xx- MAKEALL 3347 3348With the above settings build objects are saved in the /tmp/build, 3349log files are saved in the /tmp/log and the source tree remains clean 3350during the whole build process. 3351 3352 3353See also "U-Boot Porting Guide" below. 3354 3355 3356Monitor Commands - Overview: 3357============================ 3358 3359go - start application at address 'addr' 3360run - run commands in an environment variable 3361bootm - boot application image from memory 3362bootp - boot image via network using BootP/TFTP protocol 3363tftpboot- boot image via network using TFTP protocol 3364 and env variables "ipaddr" and "serverip" 3365 (and eventually "gatewayip") 3366tftpput - upload a file via network using TFTP protocol 3367rarpboot- boot image via network using RARP/TFTP protocol 3368diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 3369loads - load S-Record file over serial line 3370loadb - load binary file over serial line (kermit mode) 3371md - memory display 3372mm - memory modify (auto-incrementing) 3373nm - memory modify (constant address) 3374mw - memory write (fill) 3375cp - memory copy 3376cmp - memory compare 3377crc32 - checksum calculation 3378i2c - I2C sub-system 3379sspi - SPI utility commands 3380base - print or set address offset 3381printenv- print environment variables 3382setenv - set environment variables 3383saveenv - save environment variables to persistent storage 3384protect - enable or disable FLASH write protection 3385erase - erase FLASH memory 3386flinfo - print FLASH memory information 3387bdinfo - print Board Info structure 3388iminfo - print header information for application image 3389coninfo - print console devices and informations 3390ide - IDE sub-system 3391loop - infinite loop on address range 3392loopw - infinite write loop on address range 3393mtest - simple RAM test 3394icache - enable or disable instruction cache 3395dcache - enable or disable data cache 3396reset - Perform RESET of the CPU 3397echo - echo args to console 3398version - print monitor version 3399help - print online help 3400? - alias for 'help' 3401 3402 3403Monitor Commands - Detailed Description: 3404======================================== 3405 3406TODO. 3407 3408For now: just type "help <command>". 3409 3410 3411Environment Variables: 3412====================== 3413 3414U-Boot supports user configuration using Environment Variables which 3415can be made persistent by saving to Flash memory. 3416 3417Environment Variables are set using "setenv", printed using 3418"printenv", and saved to Flash using "saveenv". Using "setenv" 3419without a value can be used to delete a variable from the 3420environment. As long as you don't save the environment you are 3421working with an in-memory copy. In case the Flash area containing the 3422environment is erased by accident, a default environment is provided. 3423 3424Some configuration options can be set using Environment Variables. 3425 3426List of environment variables (most likely not complete): 3427 3428 baudrate - see CONFIG_BAUDRATE 3429 3430 bootdelay - see CONFIG_BOOTDELAY 3431 3432 bootcmd - see CONFIG_BOOTCOMMAND 3433 3434 bootargs - Boot arguments when booting an RTOS image 3435 3436 bootfile - Name of the image to load with TFTP 3437 3438 bootm_low - Memory range available for image processing in the bootm 3439 command can be restricted. This variable is given as 3440 a hexadecimal number and defines lowest address allowed 3441 for use by the bootm command. See also "bootm_size" 3442 environment variable. Address defined by "bootm_low" is 3443 also the base of the initial memory mapping for the Linux 3444 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 3445 bootm_mapsize. 3446 3447 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 3448 This variable is given as a hexadecimal number and it 3449 defines the size of the memory region starting at base 3450 address bootm_low that is accessible by the Linux kernel 3451 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 3452 as the default value if it is defined, and bootm_size is 3453 used otherwise. 3454 3455 bootm_size - Memory range available for image processing in the bootm 3456 command can be restricted. This variable is given as 3457 a hexadecimal number and defines the size of the region 3458 allowed for use by the bootm command. See also "bootm_low" 3459 environment variable. 3460 3461 updatefile - Location of the software update file on a TFTP server, used 3462 by the automatic software update feature. Please refer to 3463 documentation in doc/README.update for more details. 3464 3465 autoload - if set to "no" (any string beginning with 'n'), 3466 "bootp" will just load perform a lookup of the 3467 configuration from the BOOTP server, but not try to 3468 load any image using TFTP 3469 3470 autostart - if set to "yes", an image loaded using the "bootp", 3471 "rarpboot", "tftpboot" or "diskboot" commands will 3472 be automatically started (by internally calling 3473 "bootm") 3474 3475 If set to "no", a standalone image passed to the 3476 "bootm" command will be copied to the load address 3477 (and eventually uncompressed), but NOT be started. 3478 This can be used to load and uncompress arbitrary 3479 data. 3480 3481 fdt_high - if set this restricts the maximum address that the 3482 flattened device tree will be copied into upon boot. 3483 If this is set to the special value 0xFFFFFFFF then 3484 the fdt will not be copied at all on boot. For this 3485 to work it must reside in writable memory, have 3486 sufficient padding on the end of it for u-boot to 3487 add the information it needs into it, and the memory 3488 must be accessible by the kernel. 3489 3490 i2cfast - (PPC405GP|PPC405EP only) 3491 if set to 'y' configures Linux I2C driver for fast 3492 mode (400kHZ). This environment variable is used in 3493 initialization code. So, for changes to be effective 3494 it must be saved and board must be reset. 3495 3496 initrd_high - restrict positioning of initrd images: 3497 If this variable is not set, initrd images will be 3498 copied to the highest possible address in RAM; this 3499 is usually what you want since it allows for 3500 maximum initrd size. If for some reason you want to 3501 make sure that the initrd image is loaded below the 3502 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 3503 variable to a value of "no" or "off" or "0". 3504 Alternatively, you can set it to a maximum upper 3505 address to use (U-Boot will still check that it 3506 does not overwrite the U-Boot stack and data). 3507 3508 For instance, when you have a system with 16 MB 3509 RAM, and want to reserve 4 MB from use by Linux, 3510 you can do this by adding "mem=12M" to the value of 3511 the "bootargs" variable. However, now you must make 3512 sure that the initrd image is placed in the first 3513 12 MB as well - this can be done with 3514 3515 setenv initrd_high 00c00000 3516 3517 If you set initrd_high to 0xFFFFFFFF, this is an 3518 indication to U-Boot that all addresses are legal 3519 for the Linux kernel, including addresses in flash 3520 memory. In this case U-Boot will NOT COPY the 3521 ramdisk at all. This may be useful to reduce the 3522 boot time on your system, but requires that this 3523 feature is supported by your Linux kernel. 3524 3525 ipaddr - IP address; needed for tftpboot command 3526 3527 loadaddr - Default load address for commands like "bootp", 3528 "rarpboot", "tftpboot", "loadb" or "diskboot" 3529 3530 loads_echo - see CONFIG_LOADS_ECHO 3531 3532 serverip - TFTP server IP address; needed for tftpboot command 3533 3534 bootretry - see CONFIG_BOOT_RETRY_TIME 3535 3536 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 3537 3538 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 3539 3540 ethprime - controls which interface is used first. 3541 3542 ethact - controls which interface is currently active. 3543 For example you can do the following 3544 3545 => setenv ethact FEC 3546 => ping 192.168.0.1 # traffic sent on FEC 3547 => setenv ethact SCC 3548 => ping 10.0.0.1 # traffic sent on SCC 3549 3550 ethrotate - When set to "no" U-Boot does not go through all 3551 available network interfaces. 3552 It just stays at the currently selected interface. 3553 3554 netretry - When set to "no" each network operation will 3555 either succeed or fail without retrying. 3556 When set to "once" the network operation will 3557 fail when all the available network interfaces 3558 are tried once without success. 3559 Useful on scripts which control the retry operation 3560 themselves. 3561 3562 npe_ucode - set load address for the NPE microcode 3563 3564 tftpsrcport - If this is set, the value is used for TFTP's 3565 UDP source port. 3566 3567 tftpdstport - If this is set, the value is used for TFTP's UDP 3568 destination port instead of the Well Know Port 69. 3569 3570 tftpblocksize - Block size to use for TFTP transfers; if not set, 3571 we use the TFTP server's default block size 3572 3573 tftptimeout - Retransmission timeout for TFTP packets (in milli- 3574 seconds, minimum value is 1000 = 1 second). Defines 3575 when a packet is considered to be lost so it has to 3576 be retransmitted. The default is 5000 = 5 seconds. 3577 Lowering this value may make downloads succeed 3578 faster in networks with high packet loss rates or 3579 with unreliable TFTP servers. 3580 3581 vlan - When set to a value < 4095 the traffic over 3582 Ethernet is encapsulated/received over 802.1q 3583 VLAN tagged frames. 3584 3585The following image location variables contain the location of images 3586used in booting. The "Image" column gives the role of the image and is 3587not an environment variable name. The other columns are environment 3588variable names. "File Name" gives the name of the file on a TFTP 3589server, "RAM Address" gives the location in RAM the image will be 3590loaded to, and "Flash Location" gives the image's address in NOR 3591flash or offset in NAND flash. 3592 3593*Note* - these variables don't have to be defined for all boards, some 3594boards currenlty use other variables for these purposes, and some 3595boards use these variables for other purposes. 3596 3597Image File Name RAM Address Flash Location 3598----- --------- ----------- -------------- 3599u-boot u-boot u-boot_addr_r u-boot_addr 3600Linux kernel bootfile kernel_addr_r kernel_addr 3601device tree blob fdtfile fdt_addr_r fdt_addr 3602ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 3603 3604The following environment variables may be used and automatically 3605updated by the network boot commands ("bootp" and "rarpboot"), 3606depending the information provided by your boot server: 3607 3608 bootfile - see above 3609 dnsip - IP address of your Domain Name Server 3610 dnsip2 - IP address of your secondary Domain Name Server 3611 gatewayip - IP address of the Gateway (Router) to use 3612 hostname - Target hostname 3613 ipaddr - see above 3614 netmask - Subnet Mask 3615 rootpath - Pathname of the root filesystem on the NFS server 3616 serverip - see above 3617 3618 3619There are two special Environment Variables: 3620 3621 serial# - contains hardware identification information such 3622 as type string and/or serial number 3623 ethaddr - Ethernet address 3624 3625These variables can be set only once (usually during manufacturing of 3626the board). U-Boot refuses to delete or overwrite these variables 3627once they have been set once. 3628 3629 3630Further special Environment Variables: 3631 3632 ver - Contains the U-Boot version string as printed 3633 with the "version" command. This variable is 3634 readonly (see CONFIG_VERSION_VARIABLE). 3635 3636 3637Please note that changes to some configuration parameters may take 3638only effect after the next boot (yes, that's just like Windoze :-). 3639 3640 3641Command Line Parsing: 3642===================== 3643 3644There are two different command line parsers available with U-Boot: 3645the old "simple" one, and the much more powerful "hush" shell: 3646 3647Old, simple command line parser: 3648-------------------------------- 3649 3650- supports environment variables (through setenv / saveenv commands) 3651- several commands on one line, separated by ';' 3652- variable substitution using "... ${name} ..." syntax 3653- special characters ('$', ';') can be escaped by prefixing with '\', 3654 for example: 3655 setenv bootcmd bootm \${address} 3656- You can also escape text by enclosing in single apostrophes, for example: 3657 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 3658 3659Hush shell: 3660----------- 3661 3662- similar to Bourne shell, with control structures like 3663 if...then...else...fi, for...do...done; while...do...done, 3664 until...do...done, ... 3665- supports environment ("global") variables (through setenv / saveenv 3666 commands) and local shell variables (through standard shell syntax 3667 "name=value"); only environment variables can be used with "run" 3668 command 3669 3670General rules: 3671-------------- 3672 3673(1) If a command line (or an environment variable executed by a "run" 3674 command) contains several commands separated by semicolon, and 3675 one of these commands fails, then the remaining commands will be 3676 executed anyway. 3677 3678(2) If you execute several variables with one call to run (i. e. 3679 calling run with a list of variables as arguments), any failing 3680 command will cause "run" to terminate, i. e. the remaining 3681 variables are not executed. 3682 3683Note for Redundant Ethernet Interfaces: 3684======================================= 3685 3686Some boards come with redundant Ethernet interfaces; U-Boot supports 3687such configurations and is capable of automatic selection of a 3688"working" interface when needed. MAC assignment works as follows: 3689 3690Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 3691MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 3692"eth1addr" (=>eth1), "eth2addr", ... 3693 3694If the network interface stores some valid MAC address (for instance 3695in SROM), this is used as default address if there is NO correspon- 3696ding setting in the environment; if the corresponding environment 3697variable is set, this overrides the settings in the card; that means: 3698 3699o If the SROM has a valid MAC address, and there is no address in the 3700 environment, the SROM's address is used. 3701 3702o If there is no valid address in the SROM, and a definition in the 3703 environment exists, then the value from the environment variable is 3704 used. 3705 3706o If both the SROM and the environment contain a MAC address, and 3707 both addresses are the same, this MAC address is used. 3708 3709o If both the SROM and the environment contain a MAC address, and the 3710 addresses differ, the value from the environment is used and a 3711 warning is printed. 3712 3713o If neither SROM nor the environment contain a MAC address, an error 3714 is raised. 3715 3716If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 3717will be programmed into hardware as part of the initialization process. This 3718may be skipped by setting the appropriate 'ethmacskip' environment variable. 3719The naming convention is as follows: 3720"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 3721 3722Image Formats: 3723============== 3724 3725U-Boot is capable of booting (and performing other auxiliary operations on) 3726images in two formats: 3727 3728New uImage format (FIT) 3729----------------------- 3730 3731Flexible and powerful format based on Flattened Image Tree -- FIT (similar 3732to Flattened Device Tree). It allows the use of images with multiple 3733components (several kernels, ramdisks, etc.), with contents protected by 3734SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 3735 3736 3737Old uImage format 3738----------------- 3739 3740Old image format is based on binary files which can be basically anything, 3741preceded by a special header; see the definitions in include/image.h for 3742details; basically, the header defines the following image properties: 3743 3744* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 3745 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 3746 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 3747 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 3748 INTEGRITY). 3749* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 3750 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 3751 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 3752* Compression Type (uncompressed, gzip, bzip2) 3753* Load Address 3754* Entry Point 3755* Image Name 3756* Image Timestamp 3757 3758The header is marked by a special Magic Number, and both the header 3759and the data portions of the image are secured against corruption by 3760CRC32 checksums. 3761 3762 3763Linux Support: 3764============== 3765 3766Although U-Boot should support any OS or standalone application 3767easily, the main focus has always been on Linux during the design of 3768U-Boot. 3769 3770U-Boot includes many features that so far have been part of some 3771special "boot loader" code within the Linux kernel. Also, any 3772"initrd" images to be used are no longer part of one big Linux image; 3773instead, kernel and "initrd" are separate images. This implementation 3774serves several purposes: 3775 3776- the same features can be used for other OS or standalone 3777 applications (for instance: using compressed images to reduce the 3778 Flash memory footprint) 3779 3780- it becomes much easier to port new Linux kernel versions because 3781 lots of low-level, hardware dependent stuff are done by U-Boot 3782 3783- the same Linux kernel image can now be used with different "initrd" 3784 images; of course this also means that different kernel images can 3785 be run with the same "initrd". This makes testing easier (you don't 3786 have to build a new "zImage.initrd" Linux image when you just 3787 change a file in your "initrd"). Also, a field-upgrade of the 3788 software is easier now. 3789 3790 3791Linux HOWTO: 3792============ 3793 3794Porting Linux to U-Boot based systems: 3795--------------------------------------- 3796 3797U-Boot cannot save you from doing all the necessary modifications to 3798configure the Linux device drivers for use with your target hardware 3799(no, we don't intend to provide a full virtual machine interface to 3800Linux :-). 3801 3802But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 3803 3804Just make sure your machine specific header file (for instance 3805include/asm-ppc/tqm8xx.h) includes the same definition of the Board 3806Information structure as we define in include/asm-<arch>/u-boot.h, 3807and make sure that your definition of IMAP_ADDR uses the same value 3808as your U-Boot configuration in CONFIG_SYS_IMMR. 3809 3810 3811Configuring the Linux kernel: 3812----------------------------- 3813 3814No specific requirements for U-Boot. Make sure you have some root 3815device (initial ramdisk, NFS) for your target system. 3816 3817 3818Building a Linux Image: 3819----------------------- 3820 3821With U-Boot, "normal" build targets like "zImage" or "bzImage" are 3822not used. If you use recent kernel source, a new build target 3823"uImage" will exist which automatically builds an image usable by 3824U-Boot. Most older kernels also have support for a "pImage" target, 3825which was introduced for our predecessor project PPCBoot and uses a 3826100% compatible format. 3827 3828Example: 3829 3830 make TQM850L_config 3831 make oldconfig 3832 make dep 3833 make uImage 3834 3835The "uImage" build target uses a special tool (in 'tools/mkimage') to 3836encapsulate a compressed Linux kernel image with header information, 3837CRC32 checksum etc. for use with U-Boot. This is what we are doing: 3838 3839* build a standard "vmlinux" kernel image (in ELF binary format): 3840 3841* convert the kernel into a raw binary image: 3842 3843 ${CROSS_COMPILE}-objcopy -O binary \ 3844 -R .note -R .comment \ 3845 -S vmlinux linux.bin 3846 3847* compress the binary image: 3848 3849 gzip -9 linux.bin 3850 3851* package compressed binary image for U-Boot: 3852 3853 mkimage -A ppc -O linux -T kernel -C gzip \ 3854 -a 0 -e 0 -n "Linux Kernel Image" \ 3855 -d linux.bin.gz uImage 3856 3857 3858The "mkimage" tool can also be used to create ramdisk images for use 3859with U-Boot, either separated from the Linux kernel image, or 3860combined into one file. "mkimage" encapsulates the images with a 64 3861byte header containing information about target architecture, 3862operating system, image type, compression method, entry points, time 3863stamp, CRC32 checksums, etc. 3864 3865"mkimage" can be called in two ways: to verify existing images and 3866print the header information, or to build new images. 3867 3868In the first form (with "-l" option) mkimage lists the information 3869contained in the header of an existing U-Boot image; this includes 3870checksum verification: 3871 3872 tools/mkimage -l image 3873 -l ==> list image header information 3874 3875The second form (with "-d" option) is used to build a U-Boot image 3876from a "data file" which is used as image payload: 3877 3878 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 3879 -n name -d data_file image 3880 -A ==> set architecture to 'arch' 3881 -O ==> set operating system to 'os' 3882 -T ==> set image type to 'type' 3883 -C ==> set compression type 'comp' 3884 -a ==> set load address to 'addr' (hex) 3885 -e ==> set entry point to 'ep' (hex) 3886 -n ==> set image name to 'name' 3887 -d ==> use image data from 'datafile' 3888 3889Right now, all Linux kernels for PowerPC systems use the same load 3890address (0x00000000), but the entry point address depends on the 3891kernel version: 3892 3893- 2.2.x kernels have the entry point at 0x0000000C, 3894- 2.3.x and later kernels have the entry point at 0x00000000. 3895 3896So a typical call to build a U-Boot image would read: 3897 3898 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3899 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 3900 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 3901 > examples/uImage.TQM850L 3902 Image Name: 2.4.4 kernel for TQM850L 3903 Created: Wed Jul 19 02:34:59 2000 3904 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3905 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3906 Load Address: 0x00000000 3907 Entry Point: 0x00000000 3908 3909To verify the contents of the image (or check for corruption): 3910 3911 -> tools/mkimage -l examples/uImage.TQM850L 3912 Image Name: 2.4.4 kernel for TQM850L 3913 Created: Wed Jul 19 02:34:59 2000 3914 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3915 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 3916 Load Address: 0x00000000 3917 Entry Point: 0x00000000 3918 3919NOTE: for embedded systems where boot time is critical you can trade 3920speed for memory and install an UNCOMPRESSED image instead: this 3921needs more space in Flash, but boots much faster since it does not 3922need to be uncompressed: 3923 3924 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 3925 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 3926 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 3927 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 3928 > examples/uImage.TQM850L-uncompressed 3929 Image Name: 2.4.4 kernel for TQM850L 3930 Created: Wed Jul 19 02:34:59 2000 3931 Image Type: PowerPC Linux Kernel Image (uncompressed) 3932 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 3933 Load Address: 0x00000000 3934 Entry Point: 0x00000000 3935 3936 3937Similar you can build U-Boot images from a 'ramdisk.image.gz' file 3938when your kernel is intended to use an initial ramdisk: 3939 3940 -> tools/mkimage -n 'Simple Ramdisk Image' \ 3941 > -A ppc -O linux -T ramdisk -C gzip \ 3942 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 3943 Image Name: Simple Ramdisk Image 3944 Created: Wed Jan 12 14:01:50 2000 3945 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 3946 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 3947 Load Address: 0x00000000 3948 Entry Point: 0x00000000 3949 3950 3951Installing a Linux Image: 3952------------------------- 3953 3954To downloading a U-Boot image over the serial (console) interface, 3955you must convert the image to S-Record format: 3956 3957 objcopy -I binary -O srec examples/image examples/image.srec 3958 3959The 'objcopy' does not understand the information in the U-Boot 3960image header, so the resulting S-Record file will be relative to 3961address 0x00000000. To load it to a given address, you need to 3962specify the target address as 'offset' parameter with the 'loads' 3963command. 3964 3965Example: install the image to address 0x40100000 (which on the 3966TQM8xxL is in the first Flash bank): 3967 3968 => erase 40100000 401FFFFF 3969 3970 .......... done 3971 Erased 8 sectors 3972 3973 => loads 40100000 3974 ## Ready for S-Record download ... 3975 ~>examples/image.srec 3976 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 3977 ... 3978 15989 15990 15991 15992 3979 [file transfer complete] 3980 [connected] 3981 ## Start Addr = 0x00000000 3982 3983 3984You can check the success of the download using the 'iminfo' command; 3985this includes a checksum verification so you can be sure no data 3986corruption happened: 3987 3988 => imi 40100000 3989 3990 ## Checking Image at 40100000 ... 3991 Image Name: 2.2.13 for initrd on TQM850L 3992 Image Type: PowerPC Linux Kernel Image (gzip compressed) 3993 Data Size: 335725 Bytes = 327 kB = 0 MB 3994 Load Address: 00000000 3995 Entry Point: 0000000c 3996 Verifying Checksum ... OK 3997 3998 3999Boot Linux: 4000----------- 4001 4002The "bootm" command is used to boot an application that is stored in 4003memory (RAM or Flash). In case of a Linux kernel image, the contents 4004of the "bootargs" environment variable is passed to the kernel as 4005parameters. You can check and modify this variable using the 4006"printenv" and "setenv" commands: 4007 4008 4009 => printenv bootargs 4010 bootargs=root=/dev/ram 4011 4012 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4013 4014 => printenv bootargs 4015 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4016 4017 => bootm 40020000 4018 ## Booting Linux kernel at 40020000 ... 4019 Image Name: 2.2.13 for NFS on TQM850L 4020 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4021 Data Size: 381681 Bytes = 372 kB = 0 MB 4022 Load Address: 00000000 4023 Entry Point: 0000000c 4024 Verifying Checksum ... OK 4025 Uncompressing Kernel Image ... OK 4026 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 4027 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4028 time_init: decrementer frequency = 187500000/60 4029 Calibrating delay loop... 49.77 BogoMIPS 4030 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 4031 ... 4032 4033If you want to boot a Linux kernel with initial RAM disk, you pass 4034the memory addresses of both the kernel and the initrd image (PPBCOOT 4035format!) to the "bootm" command: 4036 4037 => imi 40100000 40200000 4038 4039 ## Checking Image at 40100000 ... 4040 Image Name: 2.2.13 for initrd on TQM850L 4041 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4042 Data Size: 335725 Bytes = 327 kB = 0 MB 4043 Load Address: 00000000 4044 Entry Point: 0000000c 4045 Verifying Checksum ... OK 4046 4047 ## Checking Image at 40200000 ... 4048 Image Name: Simple Ramdisk Image 4049 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4050 Data Size: 566530 Bytes = 553 kB = 0 MB 4051 Load Address: 00000000 4052 Entry Point: 00000000 4053 Verifying Checksum ... OK 4054 4055 => bootm 40100000 40200000 4056 ## Booting Linux kernel at 40100000 ... 4057 Image Name: 2.2.13 for initrd on TQM850L 4058 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4059 Data Size: 335725 Bytes = 327 kB = 0 MB 4060 Load Address: 00000000 4061 Entry Point: 0000000c 4062 Verifying Checksum ... OK 4063 Uncompressing Kernel Image ... OK 4064 ## Loading RAMDisk Image at 40200000 ... 4065 Image Name: Simple Ramdisk Image 4066 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4067 Data Size: 566530 Bytes = 553 kB = 0 MB 4068 Load Address: 00000000 4069 Entry Point: 00000000 4070 Verifying Checksum ... OK 4071 Loading Ramdisk ... OK 4072 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 4073 Boot arguments: root=/dev/ram 4074 time_init: decrementer frequency = 187500000/60 4075 Calibrating delay loop... 49.77 BogoMIPS 4076 ... 4077 RAMDISK: Compressed image found at block 0 4078 VFS: Mounted root (ext2 filesystem). 4079 4080 bash# 4081 4082Boot Linux and pass a flat device tree: 4083----------- 4084 4085First, U-Boot must be compiled with the appropriate defines. See the section 4086titled "Linux Kernel Interface" above for a more in depth explanation. The 4087following is an example of how to start a kernel and pass an updated 4088flat device tree: 4089 4090=> print oftaddr 4091oftaddr=0x300000 4092=> print oft 4093oft=oftrees/mpc8540ads.dtb 4094=> tftp $oftaddr $oft 4095Speed: 1000, full duplex 4096Using TSEC0 device 4097TFTP from server 192.168.1.1; our IP address is 192.168.1.101 4098Filename 'oftrees/mpc8540ads.dtb'. 4099Load address: 0x300000 4100Loading: # 4101done 4102Bytes transferred = 4106 (100a hex) 4103=> tftp $loadaddr $bootfile 4104Speed: 1000, full duplex 4105Using TSEC0 device 4106TFTP from server 192.168.1.1; our IP address is 192.168.1.2 4107Filename 'uImage'. 4108Load address: 0x200000 4109Loading:############ 4110done 4111Bytes transferred = 1029407 (fb51f hex) 4112=> print loadaddr 4113loadaddr=200000 4114=> print oftaddr 4115oftaddr=0x300000 4116=> bootm $loadaddr - $oftaddr 4117## Booting image at 00200000 ... 4118 Image Name: Linux-2.6.17-dirty 4119 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4120 Data Size: 1029343 Bytes = 1005.2 kB 4121 Load Address: 00000000 4122 Entry Point: 00000000 4123 Verifying Checksum ... OK 4124 Uncompressing Kernel Image ... OK 4125Booting using flat device tree at 0x300000 4126Using MPC85xx ADS machine description 4127Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 4128[snip] 4129 4130 4131More About U-Boot Image Types: 4132------------------------------ 4133 4134U-Boot supports the following image types: 4135 4136 "Standalone Programs" are directly runnable in the environment 4137 provided by U-Boot; it is expected that (if they behave 4138 well) you can continue to work in U-Boot after return from 4139 the Standalone Program. 4140 "OS Kernel Images" are usually images of some Embedded OS which 4141 will take over control completely. Usually these programs 4142 will install their own set of exception handlers, device 4143 drivers, set up the MMU, etc. - this means, that you cannot 4144 expect to re-enter U-Boot except by resetting the CPU. 4145 "RAMDisk Images" are more or less just data blocks, and their 4146 parameters (address, size) are passed to an OS kernel that is 4147 being started. 4148 "Multi-File Images" contain several images, typically an OS 4149 (Linux) kernel image and one or more data images like 4150 RAMDisks. This construct is useful for instance when you want 4151 to boot over the network using BOOTP etc., where the boot 4152 server provides just a single image file, but you want to get 4153 for instance an OS kernel and a RAMDisk image. 4154 4155 "Multi-File Images" start with a list of image sizes, each 4156 image size (in bytes) specified by an "uint32_t" in network 4157 byte order. This list is terminated by an "(uint32_t)0". 4158 Immediately after the terminating 0 follow the images, one by 4159 one, all aligned on "uint32_t" boundaries (size rounded up to 4160 a multiple of 4 bytes). 4161 4162 "Firmware Images" are binary images containing firmware (like 4163 U-Boot or FPGA images) which usually will be programmed to 4164 flash memory. 4165 4166 "Script files" are command sequences that will be executed by 4167 U-Boot's command interpreter; this feature is especially 4168 useful when you configure U-Boot to use a real shell (hush) 4169 as command interpreter. 4170 4171 4172Standalone HOWTO: 4173================= 4174 4175One of the features of U-Boot is that you can dynamically load and 4176run "standalone" applications, which can use some resources of 4177U-Boot like console I/O functions or interrupt services. 4178 4179Two simple examples are included with the sources: 4180 4181"Hello World" Demo: 4182------------------- 4183 4184'examples/hello_world.c' contains a small "Hello World" Demo 4185application; it is automatically compiled when you build U-Boot. 4186It's configured to run at address 0x00040004, so you can play with it 4187like that: 4188 4189 => loads 4190 ## Ready for S-Record download ... 4191 ~>examples/hello_world.srec 4192 1 2 3 4 5 6 7 8 9 10 11 ... 4193 [file transfer complete] 4194 [connected] 4195 ## Start Addr = 0x00040004 4196 4197 => go 40004 Hello World! This is a test. 4198 ## Starting application at 0x00040004 ... 4199 Hello World 4200 argc = 7 4201 argv[0] = "40004" 4202 argv[1] = "Hello" 4203 argv[2] = "World!" 4204 argv[3] = "This" 4205 argv[4] = "is" 4206 argv[5] = "a" 4207 argv[6] = "test." 4208 argv[7] = "<NULL>" 4209 Hit any key to exit ... 4210 4211 ## Application terminated, rc = 0x0 4212 4213Another example, which demonstrates how to register a CPM interrupt 4214handler with the U-Boot code, can be found in 'examples/timer.c'. 4215Here, a CPM timer is set up to generate an interrupt every second. 4216The interrupt service routine is trivial, just printing a '.' 4217character, but this is just a demo program. The application can be 4218controlled by the following keys: 4219 4220 ? - print current values og the CPM Timer registers 4221 b - enable interrupts and start timer 4222 e - stop timer and disable interrupts 4223 q - quit application 4224 4225 => loads 4226 ## Ready for S-Record download ... 4227 ~>examples/timer.srec 4228 1 2 3 4 5 6 7 8 9 10 11 ... 4229 [file transfer complete] 4230 [connected] 4231 ## Start Addr = 0x00040004 4232 4233 => go 40004 4234 ## Starting application at 0x00040004 ... 4235 TIMERS=0xfff00980 4236 Using timer 1 4237 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 4238 4239Hit 'b': 4240 [q, b, e, ?] Set interval 1000000 us 4241 Enabling timer 4242Hit '?': 4243 [q, b, e, ?] ........ 4244 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 4245Hit '?': 4246 [q, b, e, ?] . 4247 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 4248Hit '?': 4249 [q, b, e, ?] . 4250 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 4251Hit '?': 4252 [q, b, e, ?] . 4253 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 4254Hit 'e': 4255 [q, b, e, ?] ...Stopping timer 4256Hit 'q': 4257 [q, b, e, ?] ## Application terminated, rc = 0x0 4258 4259 4260Minicom warning: 4261================ 4262 4263Over time, many people have reported problems when trying to use the 4264"minicom" terminal emulation program for serial download. I (wd) 4265consider minicom to be broken, and recommend not to use it. Under 4266Unix, I recommend to use C-Kermit for general purpose use (and 4267especially for kermit binary protocol download ("loadb" command), and 4268use "cu" for S-Record download ("loads" command). 4269 4270Nevertheless, if you absolutely want to use it try adding this 4271configuration to your "File transfer protocols" section: 4272 4273 Name Program Name U/D FullScr IO-Red. Multi 4274 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 4275 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 4276 4277 4278NetBSD Notes: 4279============= 4280 4281Starting at version 0.9.2, U-Boot supports NetBSD both as host 4282(build U-Boot) and target system (boots NetBSD/mpc8xx). 4283 4284Building requires a cross environment; it is known to work on 4285NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 4286need gmake since the Makefiles are not compatible with BSD make). 4287Note that the cross-powerpc package does not install include files; 4288attempting to build U-Boot will fail because <machine/ansi.h> is 4289missing. This file has to be installed and patched manually: 4290 4291 # cd /usr/pkg/cross/powerpc-netbsd/include 4292 # mkdir powerpc 4293 # ln -s powerpc machine 4294 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 4295 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 4296 4297Native builds *don't* work due to incompatibilities between native 4298and U-Boot include files. 4299 4300Booting assumes that (the first part of) the image booted is a 4301stage-2 loader which in turn loads and then invokes the kernel 4302proper. Loader sources will eventually appear in the NetBSD source 4303tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 4304meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 4305 4306 4307Implementation Internals: 4308========================= 4309 4310The following is not intended to be a complete description of every 4311implementation detail. However, it should help to understand the 4312inner workings of U-Boot and make it easier to port it to custom 4313hardware. 4314 4315 4316Initial Stack, Global Data: 4317--------------------------- 4318 4319The implementation of U-Boot is complicated by the fact that U-Boot 4320starts running out of ROM (flash memory), usually without access to 4321system RAM (because the memory controller is not initialized yet). 4322This means that we don't have writable Data or BSS segments, and BSS 4323is not initialized as zero. To be able to get a C environment working 4324at all, we have to allocate at least a minimal stack. Implementation 4325options for this are defined and restricted by the CPU used: Some CPU 4326models provide on-chip memory (like the IMMR area on MPC8xx and 4327MPC826x processors), on others (parts of) the data cache can be 4328locked as (mis-) used as memory, etc. 4329 4330 Chris Hallinan posted a good summary of these issues to the 4331 U-Boot mailing list: 4332 4333 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 4334 From: "Chris Hallinan" <clh@net1plus.com> 4335 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 4336 ... 4337 4338 Correct me if I'm wrong, folks, but the way I understand it 4339 is this: Using DCACHE as initial RAM for Stack, etc, does not 4340 require any physical RAM backing up the cache. The cleverness 4341 is that the cache is being used as a temporary supply of 4342 necessary storage before the SDRAM controller is setup. It's 4343 beyond the scope of this list to explain the details, but you 4344 can see how this works by studying the cache architecture and 4345 operation in the architecture and processor-specific manuals. 4346 4347 OCM is On Chip Memory, which I believe the 405GP has 4K. It 4348 is another option for the system designer to use as an 4349 initial stack/RAM area prior to SDRAM being available. Either 4350 option should work for you. Using CS 4 should be fine if your 4351 board designers haven't used it for something that would 4352 cause you grief during the initial boot! It is frequently not 4353 used. 4354 4355 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 4356 with your processor/board/system design. The default value 4357 you will find in any recent u-boot distribution in 4358 walnut.h should work for you. I'd set it to a value larger 4359 than your SDRAM module. If you have a 64MB SDRAM module, set 4360 it above 400_0000. Just make sure your board has no resources 4361 that are supposed to respond to that address! That code in 4362 start.S has been around a while and should work as is when 4363 you get the config right. 4364 4365 -Chris Hallinan 4366 DS4.COM, Inc. 4367 4368It is essential to remember this, since it has some impact on the C 4369code for the initialization procedures: 4370 4371* Initialized global data (data segment) is read-only. Do not attempt 4372 to write it. 4373 4374* Do not use any uninitialized global data (or implicitely initialized 4375 as zero data - BSS segment) at all - this is undefined, initiali- 4376 zation is performed later (when relocating to RAM). 4377 4378* Stack space is very limited. Avoid big data buffers or things like 4379 that. 4380 4381Having only the stack as writable memory limits means we cannot use 4382normal global data to share information beween the code. But it 4383turned out that the implementation of U-Boot can be greatly 4384simplified by making a global data structure (gd_t) available to all 4385functions. We could pass a pointer to this data as argument to _all_ 4386functions, but this would bloat the code. Instead we use a feature of 4387the GCC compiler (Global Register Variables) to share the data: we 4388place a pointer (gd) to the global data into a register which we 4389reserve for this purpose. 4390 4391When choosing a register for such a purpose we are restricted by the 4392relevant (E)ABI specifications for the current architecture, and by 4393GCC's implementation. 4394 4395For PowerPC, the following registers have specific use: 4396 R1: stack pointer 4397 R2: reserved for system use 4398 R3-R4: parameter passing and return values 4399 R5-R10: parameter passing 4400 R13: small data area pointer 4401 R30: GOT pointer 4402 R31: frame pointer 4403 4404 (U-Boot also uses R12 as internal GOT pointer. r12 4405 is a volatile register so r12 needs to be reset when 4406 going back and forth between asm and C) 4407 4408 ==> U-Boot will use R2 to hold a pointer to the global data 4409 4410 Note: on PPC, we could use a static initializer (since the 4411 address of the global data structure is known at compile time), 4412 but it turned out that reserving a register results in somewhat 4413 smaller code - although the code savings are not that big (on 4414 average for all boards 752 bytes for the whole U-Boot image, 4415 624 text + 127 data). 4416 4417On Blackfin, the normal C ABI (except for P3) is followed as documented here: 4418 http://docs.blackfin.uclinux.org/doku.php?id=application_binary_interface 4419 4420 ==> U-Boot will use P3 to hold a pointer to the global data 4421 4422On ARM, the following registers are used: 4423 4424 R0: function argument word/integer result 4425 R1-R3: function argument word 4426 R9: GOT pointer 4427 R10: stack limit (used only if stack checking if enabled) 4428 R11: argument (frame) pointer 4429 R12: temporary workspace 4430 R13: stack pointer 4431 R14: link register 4432 R15: program counter 4433 4434 ==> U-Boot will use R8 to hold a pointer to the global data 4435 4436On Nios II, the ABI is documented here: 4437 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 4438 4439 ==> U-Boot will use gp to hold a pointer to the global data 4440 4441 Note: on Nios II, we give "-G0" option to gcc and don't use gp 4442 to access small data sections, so gp is free. 4443 4444On NDS32, the following registers are used: 4445 4446 R0-R1: argument/return 4447 R2-R5: argument 4448 R15: temporary register for assembler 4449 R16: trampoline register 4450 R28: frame pointer (FP) 4451 R29: global pointer (GP) 4452 R30: link register (LP) 4453 R31: stack pointer (SP) 4454 PC: program counter (PC) 4455 4456 ==> U-Boot will use R10 to hold a pointer to the global data 4457 4458NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 4459or current versions of GCC may "optimize" the code too much. 4460 4461Memory Management: 4462------------------ 4463 4464U-Boot runs in system state and uses physical addresses, i.e. the 4465MMU is not used either for address mapping nor for memory protection. 4466 4467The available memory is mapped to fixed addresses using the memory 4468controller. In this process, a contiguous block is formed for each 4469memory type (Flash, SDRAM, SRAM), even when it consists of several 4470physical memory banks. 4471 4472U-Boot is installed in the first 128 kB of the first Flash bank (on 4473TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 4474booting and sizing and initializing DRAM, the code relocates itself 4475to the upper end of DRAM. Immediately below the U-Boot code some 4476memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 4477configuration setting]. Below that, a structure with global Board 4478Info data is placed, followed by the stack (growing downward). 4479 4480Additionally, some exception handler code is copied to the low 8 kB 4481of DRAM (0x00000000 ... 0x00001FFF). 4482 4483So a typical memory configuration with 16 MB of DRAM could look like 4484this: 4485 4486 0x0000 0000 Exception Vector code 4487 : 4488 0x0000 1FFF 4489 0x0000 2000 Free for Application Use 4490 : 4491 : 4492 4493 : 4494 : 4495 0x00FB FF20 Monitor Stack (Growing downward) 4496 0x00FB FFAC Board Info Data and permanent copy of global data 4497 0x00FC 0000 Malloc Arena 4498 : 4499 0x00FD FFFF 4500 0x00FE 0000 RAM Copy of Monitor Code 4501 ... eventually: LCD or video framebuffer 4502 ... eventually: pRAM (Protected RAM - unchanged by reset) 4503 0x00FF FFFF [End of RAM] 4504 4505 4506System Initialization: 4507---------------------- 4508 4509In the reset configuration, U-Boot starts at the reset entry point 4510(on most PowerPC systems at address 0x00000100). Because of the reset 4511configuration for CS0# this is a mirror of the onboard Flash memory. 4512To be able to re-map memory U-Boot then jumps to its link address. 4513To be able to implement the initialization code in C, a (small!) 4514initial stack is set up in the internal Dual Ported RAM (in case CPUs 4515which provide such a feature like MPC8xx or MPC8260), or in a locked 4516part of the data cache. After that, U-Boot initializes the CPU core, 4517the caches and the SIU. 4518 4519Next, all (potentially) available memory banks are mapped using a 4520preliminary mapping. For example, we put them on 512 MB boundaries 4521(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 4522on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 4523programmed for SDRAM access. Using the temporary configuration, a 4524simple memory test is run that determines the size of the SDRAM 4525banks. 4526 4527When there is more than one SDRAM bank, and the banks are of 4528different size, the largest is mapped first. For equal size, the first 4529bank (CS2#) is mapped first. The first mapping is always for address 45300x00000000, with any additional banks following immediately to create 4531contiguous memory starting from 0. 4532 4533Then, the monitor installs itself at the upper end of the SDRAM area 4534and allocates memory for use by malloc() and for the global Board 4535Info data; also, the exception vector code is copied to the low RAM 4536pages, and the final stack is set up. 4537 4538Only after this relocation will you have a "normal" C environment; 4539until that you are restricted in several ways, mostly because you are 4540running from ROM, and because the code will have to be relocated to a 4541new address in RAM. 4542 4543 4544U-Boot Porting Guide: 4545---------------------- 4546 4547[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 4548list, October 2002] 4549 4550 4551int main(int argc, char *argv[]) 4552{ 4553 sighandler_t no_more_time; 4554 4555 signal(SIGALRM, no_more_time); 4556 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 4557 4558 if (available_money > available_manpower) { 4559 Pay consultant to port U-Boot; 4560 return 0; 4561 } 4562 4563 Download latest U-Boot source; 4564 4565 Subscribe to u-boot mailing list; 4566 4567 if (clueless) 4568 email("Hi, I am new to U-Boot, how do I get started?"); 4569 4570 while (learning) { 4571 Read the README file in the top level directory; 4572 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 4573 Read applicable doc/*.README; 4574 Read the source, Luke; 4575 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 4576 } 4577 4578 if (available_money > toLocalCurrency ($2500)) 4579 Buy a BDI3000; 4580 else 4581 Add a lot of aggravation and time; 4582 4583 if (a similar board exists) { /* hopefully... */ 4584 cp -a board/<similar> board/<myboard> 4585 cp include/configs/<similar>.h include/configs/<myboard>.h 4586 } else { 4587 Create your own board support subdirectory; 4588 Create your own board include/configs/<myboard>.h file; 4589 } 4590 Edit new board/<myboard> files 4591 Edit new include/configs/<myboard>.h 4592 4593 while (!accepted) { 4594 while (!running) { 4595 do { 4596 Add / modify source code; 4597 } until (compiles); 4598 Debug; 4599 if (clueless) 4600 email("Hi, I am having problems..."); 4601 } 4602 Send patch file to the U-Boot email list; 4603 if (reasonable critiques) 4604 Incorporate improvements from email list code review; 4605 else 4606 Defend code as written; 4607 } 4608 4609 return 0; 4610} 4611 4612void no_more_time (int sig) 4613{ 4614 hire_a_guru(); 4615} 4616 4617 4618Coding Standards: 4619----------------- 4620 4621All contributions to U-Boot should conform to the Linux kernel 4622coding style; see the file "Documentation/CodingStyle" and the script 4623"scripts/Lindent" in your Linux kernel source directory. 4624 4625Source files originating from a different project (for example the 4626MTD subsystem) are generally exempt from these guidelines and are not 4627reformated to ease subsequent migration to newer versions of those 4628sources. 4629 4630Please note that U-Boot is implemented in C (and to some small parts in 4631Assembler); no C++ is used, so please do not use C++ style comments (//) 4632in your code. 4633 4634Please also stick to the following formatting rules: 4635- remove any trailing white space 4636- use TAB characters for indentation and vertical alignment, not spaces 4637- make sure NOT to use DOS '\r\n' line feeds 4638- do not add more than 2 consecutive empty lines to source files 4639- do not add trailing empty lines to source files 4640 4641Submissions which do not conform to the standards may be returned 4642with a request to reformat the changes. 4643 4644 4645Submitting Patches: 4646------------------- 4647 4648Since the number of patches for U-Boot is growing, we need to 4649establish some rules. Submissions which do not conform to these rules 4650may be rejected, even when they contain important and valuable stuff. 4651 4652Please see http://www.denx.de/wiki/U-Boot/Patches for details. 4653 4654Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 4655see http://lists.denx.de/mailman/listinfo/u-boot 4656 4657When you send a patch, please include the following information with 4658it: 4659 4660* For bug fixes: a description of the bug and how your patch fixes 4661 this bug. Please try to include a way of demonstrating that the 4662 patch actually fixes something. 4663 4664* For new features: a description of the feature and your 4665 implementation. 4666 4667* A CHANGELOG entry as plaintext (separate from the patch) 4668 4669* For major contributions, your entry to the CREDITS file 4670 4671* When you add support for a new board, don't forget to add this 4672 board to the MAINTAINERS file, too. 4673 4674* If your patch adds new configuration options, don't forget to 4675 document these in the README file. 4676 4677* The patch itself. If you are using git (which is *strongly* 4678 recommended) you can easily generate the patch using the 4679 "git format-patch". If you then use "git send-email" to send it to 4680 the U-Boot mailing list, you will avoid most of the common problems 4681 with some other mail clients. 4682 4683 If you cannot use git, use "diff -purN OLD NEW". If your version of 4684 diff does not support these options, then get the latest version of 4685 GNU diff. 4686 4687 The current directory when running this command shall be the parent 4688 directory of the U-Boot source tree (i. e. please make sure that 4689 your patch includes sufficient directory information for the 4690 affected files). 4691 4692 We prefer patches as plain text. MIME attachments are discouraged, 4693 and compressed attachments must not be used. 4694 4695* If one logical set of modifications affects or creates several 4696 files, all these changes shall be submitted in a SINGLE patch file. 4697 4698* Changesets that contain different, unrelated modifications shall be 4699 submitted as SEPARATE patches, one patch per changeset. 4700 4701 4702Notes: 4703 4704* Before sending the patch, run the MAKEALL script on your patched 4705 source tree and make sure that no errors or warnings are reported 4706 for any of the boards. 4707 4708* Keep your modifications to the necessary minimum: A patch 4709 containing several unrelated changes or arbitrary reformats will be 4710 returned with a request to re-formatting / split it. 4711 4712* If you modify existing code, make sure that your new code does not 4713 add to the memory footprint of the code ;-) Small is beautiful! 4714 When adding new features, these should compile conditionally only 4715 (using #ifdef), and the resulting code with the new feature 4716 disabled must not need more memory than the old code without your 4717 modification. 4718 4719* Remember that there is a size limit of 100 kB per message on the 4720 u-boot mailing list. Bigger patches will be moderated. If they are 4721 reasonable and not too big, they will be acknowledged. But patches 4722 bigger than the size limit should be avoided. 4723