1# 2# (C) Copyright 2000 - 2013 3# Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4# 5# SPDX-License-Identifier: GPL-2.0+ 6# 7 8Summary: 9======== 10 11This directory contains the source code for U-Boot, a boot loader for 12Embedded boards based on PowerPC, ARM, MIPS and several other 13processors, which can be installed in a boot ROM and used to 14initialize and test the hardware or to download and run application 15code. 16 17The development of U-Boot is closely related to Linux: some parts of 18the source code originate in the Linux source tree, we have some 19header files in common, and special provision has been made to 20support booting of Linux images. 21 22Some attention has been paid to make this software easily 23configurable and extendable. For instance, all monitor commands are 24implemented with the same call interface, so that it's very easy to 25add new commands. Also, instead of permanently adding rarely used 26code (for instance hardware test utilities) to the monitor, you can 27load and run it dynamically. 28 29 30Status: 31======= 32 33In general, all boards for which a configuration option exists in the 34Makefile have been tested to some extent and can be considered 35"working". In fact, many of them are used in production systems. 36 37In case of problems see the CHANGELOG file to find out who contributed 38the specific port. In addition, there are various MAINTAINERS files 39scattered throughout the U-Boot source identifying the people or 40companies responsible for various boards and subsystems. 41 42Note: As of August, 2010, there is no longer a CHANGELOG file in the 43actual U-Boot source tree; however, it can be created dynamically 44from the Git log using: 45 46 make CHANGELOG 47 48 49Where to get help: 50================== 51 52In case you have questions about, problems with or contributions for 53U-Boot, you should send a message to the U-Boot mailing list at 54<u-boot@lists.denx.de>. There is also an archive of previous traffic 55on the mailing list - please search the archive before asking FAQ's. 56Please see http://lists.denx.de/pipermail/u-boot and 57http://dir.gmane.org/gmane.comp.boot-loaders.u-boot 58 59 60Where to get source code: 61========================= 62 63The U-Boot source code is maintained in the Git repository at 64git://www.denx.de/git/u-boot.git ; you can browse it online at 65http://www.denx.de/cgi-bin/gitweb.cgi?p=u-boot.git;a=summary 66 67The "snapshot" links on this page allow you to download tarballs of 68any version you might be interested in. Official releases are also 69available for FTP download from the ftp://ftp.denx.de/pub/u-boot/ 70directory. 71 72Pre-built (and tested) images are available from 73ftp://ftp.denx.de/pub/u-boot/images/ 74 75 76Where we come from: 77=================== 78 79- start from 8xxrom sources 80- create PPCBoot project (http://sourceforge.net/projects/ppcboot) 81- clean up code 82- make it easier to add custom boards 83- make it possible to add other [PowerPC] CPUs 84- extend functions, especially: 85 * Provide extended interface to Linux boot loader 86 * S-Record download 87 * network boot 88 * PCMCIA / CompactFlash / ATA disk / SCSI ... boot 89- create ARMBoot project (http://sourceforge.net/projects/armboot) 90- add other CPU families (starting with ARM) 91- create U-Boot project (http://sourceforge.net/projects/u-boot) 92- current project page: see http://www.denx.de/wiki/U-Boot 93 94 95Names and Spelling: 96=================== 97 98The "official" name of this project is "Das U-Boot". The spelling 99"U-Boot" shall be used in all written text (documentation, comments 100in source files etc.). Example: 101 102 This is the README file for the U-Boot project. 103 104File names etc. shall be based on the string "u-boot". Examples: 105 106 include/asm-ppc/u-boot.h 107 108 #include <asm/u-boot.h> 109 110Variable names, preprocessor constants etc. shall be either based on 111the string "u_boot" or on "U_BOOT". Example: 112 113 U_BOOT_VERSION u_boot_logo 114 IH_OS_U_BOOT u_boot_hush_start 115 116 117Versioning: 118=========== 119 120Starting with the release in October 2008, the names of the releases 121were changed from numerical release numbers without deeper meaning 122into a time stamp based numbering. Regular releases are identified by 123names consisting of the calendar year and month of the release date. 124Additional fields (if present) indicate release candidates or bug fix 125releases in "stable" maintenance trees. 126 127Examples: 128 U-Boot v2009.11 - Release November 2009 129 U-Boot v2009.11.1 - Release 1 in version November 2009 stable tree 130 U-Boot v2010.09-rc1 - Release candidate 1 for September 2010 release 131 132 133Directory Hierarchy: 134==================== 135 136/arch Architecture specific files 137 /arc Files generic to ARC architecture 138 /arm Files generic to ARM architecture 139 /avr32 Files generic to AVR32 architecture 140 /m68k Files generic to m68k architecture 141 /microblaze Files generic to microblaze architecture 142 /mips Files generic to MIPS architecture 143 /nds32 Files generic to NDS32 architecture 144 /nios2 Files generic to Altera NIOS2 architecture 145 /openrisc Files generic to OpenRISC architecture 146 /powerpc Files generic to PowerPC architecture 147 /sandbox Files generic to HW-independent "sandbox" 148 /sh Files generic to SH architecture 149 /x86 Files generic to x86 architecture 150/api Machine/arch independent API for external apps 151/board Board dependent files 152/cmd U-Boot commands functions 153/common Misc architecture independent functions 154/configs Board default configuration files 155/disk Code for disk drive partition handling 156/doc Documentation (don't expect too much) 157/drivers Commonly used device drivers 158/dts Contains Makefile for building internal U-Boot fdt. 159/examples Example code for standalone applications, etc. 160/fs Filesystem code (cramfs, ext2, jffs2, etc.) 161/include Header Files 162/lib Library routines generic to all architectures 163/Licenses Various license files 164/net Networking code 165/post Power On Self Test 166/scripts Various build scripts and Makefiles 167/test Various unit test files 168/tools Tools to build S-Record or U-Boot images, etc. 169 170Software Configuration: 171======================= 172 173Configuration is usually done using C preprocessor defines; the 174rationale behind that is to avoid dead code whenever possible. 175 176There are two classes of configuration variables: 177 178* Configuration _OPTIONS_: 179 These are selectable by the user and have names beginning with 180 "CONFIG_". 181 182* Configuration _SETTINGS_: 183 These depend on the hardware etc. and should not be meddled with if 184 you don't know what you're doing; they have names beginning with 185 "CONFIG_SYS_". 186 187Previously, all configuration was done by hand, which involved creating 188symbolic links and editing configuration files manually. More recently, 189U-Boot has added the Kbuild infrastructure used by the Linux kernel, 190allowing you to use the "make menuconfig" command to configure your 191build. 192 193 194Selection of Processor Architecture and Board Type: 195--------------------------------------------------- 196 197For all supported boards there are ready-to-use default 198configurations available; just type "make <board_name>_defconfig". 199 200Example: For a TQM823L module type: 201 202 cd u-boot 203 make TQM823L_defconfig 204 205Note: If you're looking for the default configuration file for a board 206you're sure used to be there but is now missing, check the file 207doc/README.scrapyard for a list of no longer supported boards. 208 209Sandbox Environment: 210-------------------- 211 212U-Boot can be built natively to run on a Linux host using the 'sandbox' 213board. This allows feature development which is not board- or architecture- 214specific to be undertaken on a native platform. The sandbox is also used to 215run some of U-Boot's tests. 216 217See board/sandbox/README.sandbox for more details. 218 219 220Board Initialisation Flow: 221-------------------------- 222 223This is the intended start-up flow for boards. This should apply for both 224SPL and U-Boot proper (i.e. they both follow the same rules). 225 226Note: "SPL" stands for "Secondary Program Loader," which is explained in 227more detail later in this file. 228 229At present, SPL mostly uses a separate code path, but the function names 230and roles of each function are the same. Some boards or architectures 231may not conform to this. At least most ARM boards which use 232CONFIG_SPL_FRAMEWORK conform to this. 233 234Execution typically starts with an architecture-specific (and possibly 235CPU-specific) start.S file, such as: 236 237 - arch/arm/cpu/armv7/start.S 238 - arch/powerpc/cpu/mpc83xx/start.S 239 - arch/mips/cpu/start.S 240 241and so on. From there, three functions are called; the purpose and 242limitations of each of these functions are described below. 243 244lowlevel_init(): 245 - purpose: essential init to permit execution to reach board_init_f() 246 - no global_data or BSS 247 - there is no stack (ARMv7 may have one but it will soon be removed) 248 - must not set up SDRAM or use console 249 - must only do the bare minimum to allow execution to continue to 250 board_init_f() 251 - this is almost never needed 252 - return normally from this function 253 254board_init_f(): 255 - purpose: set up the machine ready for running board_init_r(): 256 i.e. SDRAM and serial UART 257 - global_data is available 258 - stack is in SRAM 259 - BSS is not available, so you cannot use global/static variables, 260 only stack variables and global_data 261 262 Non-SPL-specific notes: 263 - dram_init() is called to set up DRAM. If already done in SPL this 264 can do nothing 265 266 SPL-specific notes: 267 - you can override the entire board_init_f() function with your own 268 version as needed. 269 - preloader_console_init() can be called here in extremis 270 - should set up SDRAM, and anything needed to make the UART work 271 - these is no need to clear BSS, it will be done by crt0.S 272 - must return normally from this function (don't call board_init_r() 273 directly) 274 275Here the BSS is cleared. For SPL, if CONFIG_SPL_STACK_R is defined, then at 276this point the stack and global_data are relocated to below 277CONFIG_SPL_STACK_R_ADDR. For non-SPL, U-Boot is relocated to run at the top of 278memory. 279 280board_init_r(): 281 - purpose: main execution, common code 282 - global_data is available 283 - SDRAM is available 284 - BSS is available, all static/global variables can be used 285 - execution eventually continues to main_loop() 286 287 Non-SPL-specific notes: 288 - U-Boot is relocated to the top of memory and is now running from 289 there. 290 291 SPL-specific notes: 292 - stack is optionally in SDRAM, if CONFIG_SPL_STACK_R is defined and 293 CONFIG_SPL_STACK_R_ADDR points into SDRAM 294 - preloader_console_init() can be called here - typically this is 295 done by selecting CONFIG_SPL_BOARD_INIT and then supplying a 296 spl_board_init() function containing this call 297 - loads U-Boot or (in falcon mode) Linux 298 299 300 301Configuration Options: 302---------------------- 303 304Configuration depends on the combination of board and CPU type; all 305such information is kept in a configuration file 306"include/configs/<board_name>.h". 307 308Example: For a TQM823L module, all configuration settings are in 309"include/configs/TQM823L.h". 310 311 312Many of the options are named exactly as the corresponding Linux 313kernel configuration options. The intention is to make it easier to 314build a config tool - later. 315 316 317The following options need to be configured: 318 319- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 320 321- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 322 323- CPU Daughterboard Type: (if CONFIG_ATSTK1000 is defined) 324 Define exactly one, e.g. CONFIG_ATSTK1002 325 326- Marvell Family Member 327 CONFIG_SYS_MVFS - define it if you want to enable 328 multiple fs option at one time 329 for marvell soc family 330 331- 8xx CPU Options: (if using an MPC8xx CPU) 332 CONFIG_8xx_GCLK_FREQ - deprecated: CPU clock if 333 get_gclk_freq() cannot work 334 e.g. if there is no 32KHz 335 reference PIT/RTC clock 336 CONFIG_8xx_OSCLK - PLL input clock (either EXTCLK 337 or XTAL/EXTAL) 338 339- 859/866/885 CPU options: (if using a MPC859 or MPC866 or MPC885 CPU): 340 CONFIG_SYS_8xx_CPUCLK_MIN 341 CONFIG_SYS_8xx_CPUCLK_MAX 342 CONFIG_8xx_CPUCLK_DEFAULT 343 See doc/README.MPC866 344 345 CONFIG_SYS_MEASURE_CPUCLK 346 347 Define this to measure the actual CPU clock instead 348 of relying on the correctness of the configured 349 values. Mostly useful for board bringup to make sure 350 the PLL is locked at the intended frequency. Note 351 that this requires a (stable) reference clock (32 kHz 352 RTC clock or CONFIG_SYS_8XX_XIN) 353 354 CONFIG_SYS_DELAYED_ICACHE 355 356 Define this option if you want to enable the 357 ICache only when Code runs from RAM. 358 359- 85xx CPU Options: 360 CONFIG_SYS_PPC64 361 362 Specifies that the core is a 64-bit PowerPC implementation (implements 363 the "64" category of the Power ISA). This is necessary for ePAPR 364 compliance, among other possible reasons. 365 366 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 CONFIG_SYS_FSL_ERRATUM_A004510 378 379 Enables a workaround for erratum A004510. If set, 380 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 381 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 382 383 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 384 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 385 386 Defines one or two SoC revisions (low 8 bits of SVR) 387 for which the A004510 workaround should be applied. 388 389 The rest of SVR is either not relevant to the decision 390 of whether the erratum is present (e.g. p2040 versus 391 p2041) or is implied by the build target, which controls 392 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 393 394 See Freescale App Note 4493 for more information about 395 this erratum. 396 397 CONFIG_A003399_NOR_WORKAROUND 398 Enables a workaround for IFC erratum A003399. It is only 399 required during NOR boot. 400 401 CONFIG_A008044_WORKAROUND 402 Enables a workaround for T1040/T1042 erratum A008044. It is only 403 required during NAND boot and valid for Rev 1.0 SoC revision 404 405 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 406 407 This is the value to write into CCSR offset 0x18600 408 according to the A004510 workaround. 409 410 CONFIG_SYS_FSL_DSP_DDR_ADDR 411 This value denotes start offset of DDR memory which is 412 connected exclusively to the DSP cores. 413 414 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 415 This value denotes start offset of M2 memory 416 which is directly connected to the DSP core. 417 418 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 419 This value denotes start offset of M3 memory which is directly 420 connected to the DSP core. 421 422 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 423 This value denotes start offset of DSP CCSR space. 424 425 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 426 Single Source Clock is clocking mode present in some of FSL SoC's. 427 In this mode, a single differential clock is used to supply 428 clocks to the sysclock, ddrclock and usbclock. 429 430 CONFIG_SYS_CPC_REINIT_F 431 This CONFIG is defined when the CPC is configured as SRAM at the 432 time of U-Boot entry and is required to be re-initialized. 433 434 CONFIG_DEEP_SLEEP 435 Indicates this SoC supports deep sleep feature. If deep sleep is 436 supported, core will start to execute uboot when wakes up. 437 438- Generic CPU options: 439 CONFIG_SYS_GENERIC_GLOBAL_DATA 440 Defines global data is initialized in generic board board_init_f(). 441 If this macro is defined, global data is created and cleared in 442 generic board board_init_f(). Without this macro, architecture/board 443 should initialize global data before calling board_init_f(). 444 445 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 446 447 Defines the endianess of the CPU. Implementation of those 448 values is arch specific. 449 450 CONFIG_SYS_FSL_DDR 451 Freescale DDR driver in use. This type of DDR controller is 452 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 453 SoCs. 454 455 CONFIG_SYS_FSL_DDR_ADDR 456 Freescale DDR memory-mapped register base. 457 458 CONFIG_SYS_FSL_DDR_EMU 459 Specify emulator support for DDR. Some DDR features such as 460 deskew training are not available. 461 462 CONFIG_SYS_FSL_DDRC_GEN1 463 Freescale DDR1 controller. 464 465 CONFIG_SYS_FSL_DDRC_GEN2 466 Freescale DDR2 controller. 467 468 CONFIG_SYS_FSL_DDRC_GEN3 469 Freescale DDR3 controller. 470 471 CONFIG_SYS_FSL_DDRC_GEN4 472 Freescale DDR4 controller. 473 474 CONFIG_SYS_FSL_DDRC_ARM_GEN3 475 Freescale DDR3 controller for ARM-based SoCs. 476 477 CONFIG_SYS_FSL_DDR1 478 Board config to use DDR1. It can be enabled for SoCs with 479 Freescale DDR1 or DDR2 controllers, depending on the board 480 implemetation. 481 482 CONFIG_SYS_FSL_DDR2 483 Board config to use DDR2. It can be enabled for SoCs with 484 Freescale DDR2 or DDR3 controllers, depending on the board 485 implementation. 486 487 CONFIG_SYS_FSL_DDR3 488 Board config to use DDR3. It can be enabled for SoCs with 489 Freescale DDR3 or DDR3L controllers. 490 491 CONFIG_SYS_FSL_DDR3L 492 Board config to use DDR3L. It can be enabled for SoCs with 493 DDR3L controllers. 494 495 CONFIG_SYS_FSL_DDR4 496 Board config to use DDR4. It can be enabled for SoCs with 497 DDR4 controllers. 498 499 CONFIG_SYS_FSL_IFC_BE 500 Defines the IFC controller register space as Big Endian 501 502 CONFIG_SYS_FSL_IFC_LE 503 Defines the IFC controller register space as Little Endian 504 505 CONFIG_SYS_FSL_IFC_CLK_DIV 506 Defines divider of platform clock(clock input to IFC controller). 507 508 CONFIG_SYS_FSL_LBC_CLK_DIV 509 Defines divider of platform clock(clock input to eLBC controller). 510 511 CONFIG_SYS_FSL_PBL_PBI 512 It enables addition of RCW (Power on reset configuration) in built image. 513 Please refer doc/README.pblimage for more details 514 515 CONFIG_SYS_FSL_PBL_RCW 516 It adds PBI(pre-boot instructions) commands in u-boot build image. 517 PBI commands can be used to configure SoC before it starts the execution. 518 Please refer doc/README.pblimage for more details 519 520 CONFIG_SPL_FSL_PBL 521 It adds a target to create boot binary having SPL binary in PBI format 522 concatenated with u-boot binary. 523 524 CONFIG_SYS_FSL_DDR_BE 525 Defines the DDR controller register space as Big Endian 526 527 CONFIG_SYS_FSL_DDR_LE 528 Defines the DDR controller register space as Little Endian 529 530 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 531 Physical address from the view of DDR controllers. It is the 532 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 533 it could be different for ARM SoCs. 534 535 CONFIG_SYS_FSL_DDR_INTLV_256B 536 DDR controller interleaving on 256-byte. This is a special 537 interleaving mode, handled by Dickens for Freescale layerscape 538 SoCs with ARM core. 539 540 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 541 Number of controllers used as main memory. 542 543 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 544 Number of controllers used for other than main memory. 545 546 CONFIG_SYS_FSL_HAS_DP_DDR 547 Defines the SoC has DP-DDR used for DPAA. 548 549 CONFIG_SYS_FSL_SEC_BE 550 Defines the SEC controller register space as Big Endian 551 552 CONFIG_SYS_FSL_SEC_LE 553 Defines the SEC controller register space as Little Endian 554 555- MIPS CPU options: 556 CONFIG_SYS_INIT_SP_OFFSET 557 558 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 559 pointer. This is needed for the temporary stack before 560 relocation. 561 562 CONFIG_SYS_MIPS_CACHE_MODE 563 564 Cache operation mode for the MIPS CPU. 565 See also arch/mips/include/asm/mipsregs.h. 566 Possible values are: 567 CONF_CM_CACHABLE_NO_WA 568 CONF_CM_CACHABLE_WA 569 CONF_CM_UNCACHED 570 CONF_CM_CACHABLE_NONCOHERENT 571 CONF_CM_CACHABLE_CE 572 CONF_CM_CACHABLE_COW 573 CONF_CM_CACHABLE_CUW 574 CONF_CM_CACHABLE_ACCELERATED 575 576 CONFIG_SYS_XWAY_EBU_BOOTCFG 577 578 Special option for Lantiq XWAY SoCs for booting from NOR flash. 579 See also arch/mips/cpu/mips32/start.S. 580 581 CONFIG_XWAY_SWAP_BYTES 582 583 Enable compilation of tools/xway-swap-bytes needed for Lantiq 584 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 585 be swapped if a flash programmer is used. 586 587- ARM options: 588 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 589 590 Select high exception vectors of the ARM core, e.g., do not 591 clear the V bit of the c1 register of CP15. 592 593 COUNTER_FREQUENCY 594 Generic timer clock source frequency. 595 596 COUNTER_FREQUENCY_REAL 597 Generic timer clock source frequency if the real clock is 598 different from COUNTER_FREQUENCY, and can only be determined 599 at run time. 600 601- Tegra SoC options: 602 CONFIG_TEGRA_SUPPORT_NON_SECURE 603 604 Support executing U-Boot in non-secure (NS) mode. Certain 605 impossible actions will be skipped if the CPU is in NS mode, 606 such as ARM architectural timer initialization. 607 608- Linux Kernel Interface: 609 CONFIG_CLOCKS_IN_MHZ 610 611 U-Boot stores all clock information in Hz 612 internally. For binary compatibility with older Linux 613 kernels (which expect the clocks passed in the 614 bd_info data to be in MHz) the environment variable 615 "clocks_in_mhz" can be defined so that U-Boot 616 converts clock data to MHZ before passing it to the 617 Linux kernel. 618 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 619 "clocks_in_mhz=1" is automatically included in the 620 default environment. 621 622 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 623 624 When transferring memsize parameter to Linux, some versions 625 expect it to be in bytes, others in MB. 626 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 627 628 CONFIG_OF_LIBFDT 629 630 New kernel versions are expecting firmware settings to be 631 passed using flattened device trees (based on open firmware 632 concepts). 633 634 CONFIG_OF_LIBFDT 635 * New libfdt-based support 636 * Adds the "fdt" command 637 * The bootm command automatically updates the fdt 638 639 OF_CPU - The proper name of the cpus node (only required for 640 MPC512X and MPC5xxx based boards). 641 OF_SOC - The proper name of the soc node (only required for 642 MPC512X and MPC5xxx based boards). 643 OF_TBCLK - The timebase frequency. 644 OF_STDOUT_PATH - The path to the console device 645 646 boards with QUICC Engines require OF_QE to set UCC MAC 647 addresses 648 649 CONFIG_OF_BOARD_SETUP 650 651 Board code has addition modification that it wants to make 652 to the flat device tree before handing it off to the kernel 653 654 CONFIG_OF_SYSTEM_SETUP 655 656 Other code has addition modification that it wants to make 657 to the flat device tree before handing it off to the kernel. 658 This causes ft_system_setup() to be called before booting 659 the kernel. 660 661 CONFIG_OF_IDE_FIXUP 662 663 U-Boot can detect if an IDE device is present or not. 664 If not, and this new config option is activated, U-Boot 665 removes the ATA node from the DTS before booting Linux, 666 so the Linux IDE driver does not probe the device and 667 crash. This is needed for buggy hardware (uc101) where 668 no pull down resistor is connected to the signal IDE5V_DD7. 669 670 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 671 672 This setting is mandatory for all boards that have only one 673 machine type and must be used to specify the machine type 674 number as it appears in the ARM machine registry 675 (see http://www.arm.linux.org.uk/developer/machines/). 676 Only boards that have multiple machine types supported 677 in a single configuration file and the machine type is 678 runtime discoverable, do not have to use this setting. 679 680- vxWorks boot parameters: 681 682 bootvx constructs a valid bootline using the following 683 environments variables: bootdev, bootfile, ipaddr, netmask, 684 serverip, gatewayip, hostname, othbootargs. 685 It loads the vxWorks image pointed bootfile. 686 687 Note: If a "bootargs" environment is defined, it will overwride 688 the defaults discussed just above. 689 690- Cache Configuration: 691 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 692 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 693 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 694 695- Cache Configuration for ARM: 696 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 697 controller 698 CONFIG_SYS_PL310_BASE - Physical base address of PL310 699 controller register space 700 701- Serial Ports: 702 CONFIG_PL010_SERIAL 703 704 Define this if you want support for Amba PrimeCell PL010 UARTs. 705 706 CONFIG_PL011_SERIAL 707 708 Define this if you want support for Amba PrimeCell PL011 UARTs. 709 710 CONFIG_PL011_CLOCK 711 712 If you have Amba PrimeCell PL011 UARTs, set this variable to 713 the clock speed of the UARTs. 714 715 CONFIG_PL01x_PORTS 716 717 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 718 define this to a list of base addresses for each (supported) 719 port. See e.g. include/configs/versatile.h 720 721 CONFIG_SERIAL_HW_FLOW_CONTROL 722 723 Define this variable to enable hw flow control in serial driver. 724 Current user of this option is drivers/serial/nsl16550.c driver 725 726- Console Interface: 727 Depending on board, define exactly one serial port 728 (like CONFIG_8xx_CONS_SMC1, CONFIG_8xx_CONS_SMC2, 729 CONFIG_8xx_CONS_SCC1, ...), or switch off the serial 730 console by defining CONFIG_8xx_CONS_NONE 731 732 Note: if CONFIG_8xx_CONS_NONE is defined, the serial 733 port routines must be defined elsewhere 734 (i.e. serial_init(), serial_getc(), ...) 735 736- Console Baudrate: 737 CONFIG_BAUDRATE - in bps 738 Select one of the baudrates listed in 739 CONFIG_SYS_BAUDRATE_TABLE, see below. 740 CONFIG_SYS_BRGCLK_PRESCALE, baudrate prescale 741 742- Console Rx buffer length 743 With CONFIG_SYS_SMC_RXBUFLEN it is possible to define 744 the maximum receive buffer length for the SMC. 745 This option is actual only for 82xx and 8xx possible. 746 If using CONFIG_SYS_SMC_RXBUFLEN also CONFIG_SYS_MAXIDLE 747 must be defined, to setup the maximum idle timeout for 748 the SMC. 749 750- Autoboot Command: 751 CONFIG_BOOTCOMMAND 752 Only needed when CONFIG_BOOTDELAY is enabled; 753 define a command string that is automatically executed 754 when no character is read on the console interface 755 within "Boot Delay" after reset. 756 757 CONFIG_BOOTARGS 758 This can be used to pass arguments to the bootm 759 command. The value of CONFIG_BOOTARGS goes into the 760 environment value "bootargs". 761 762 CONFIG_RAMBOOT and CONFIG_NFSBOOT 763 The value of these goes into the environment as 764 "ramboot" and "nfsboot" respectively, and can be used 765 as a convenience, when switching between booting from 766 RAM and NFS. 767 768- Bootcount: 769 CONFIG_BOOTCOUNT_LIMIT 770 Implements a mechanism for detecting a repeating reboot 771 cycle, see: 772 http://www.denx.de/wiki/view/DULG/UBootBootCountLimit 773 774 CONFIG_BOOTCOUNT_ENV 775 If no softreset save registers are found on the hardware 776 "bootcount" is stored in the environment. To prevent a 777 saveenv on all reboots, the environment variable 778 "upgrade_available" is used. If "upgrade_available" is 779 0, "bootcount" is always 0, if "upgrade_available" is 780 1 "bootcount" is incremented in the environment. 781 So the Userspace Applikation must set the "upgrade_available" 782 and "bootcount" variable to 0, if a boot was successfully. 783 784- Pre-Boot Commands: 785 CONFIG_PREBOOT 786 787 When this option is #defined, the existence of the 788 environment variable "preboot" will be checked 789 immediately before starting the CONFIG_BOOTDELAY 790 countdown and/or running the auto-boot command resp. 791 entering interactive mode. 792 793 This feature is especially useful when "preboot" is 794 automatically generated or modified. For an example 795 see the LWMON board specific code: here "preboot" is 796 modified when the user holds down a certain 797 combination of keys on the (special) keyboard when 798 booting the systems 799 800- Serial Download Echo Mode: 801 CONFIG_LOADS_ECHO 802 If defined to 1, all characters received during a 803 serial download (using the "loads" command) are 804 echoed back. This might be needed by some terminal 805 emulations (like "cu"), but may as well just take 806 time on others. This setting #define's the initial 807 value of the "loads_echo" environment variable. 808 809- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 810 CONFIG_KGDB_BAUDRATE 811 Select one of the baudrates listed in 812 CONFIG_SYS_BAUDRATE_TABLE, see below. 813 814- Monitor Functions: 815 Monitor commands can be included or excluded 816 from the build by using the #include files 817 <config_cmd_all.h> and #undef'ing unwanted 818 commands, or adding #define's for wanted commands. 819 820 The default command configuration includes all commands 821 except those marked below with a "*". 822 823 CONFIG_CMD_AES AES 128 CBC encrypt/decrypt 824 CONFIG_CMD_ASKENV * ask for env variable 825 CONFIG_CMD_BDI bdinfo 826 CONFIG_CMD_BOOTD bootd 827 CONFIG_CMD_BOOTI * ARM64 Linux kernel Image support 828 CONFIG_CMD_CACHE * icache, dcache 829 CONFIG_CMD_CONSOLE coninfo 830 CONFIG_CMD_CRC32 * crc32 831 CONFIG_CMD_DHCP * DHCP support 832 CONFIG_CMD_DIAG * Diagnostics 833 CONFIG_CMD_DTT * Digital Therm and Thermostat 834 CONFIG_CMD_ECHO echo arguments 835 CONFIG_CMD_EDITENV edit env variable 836 CONFIG_CMD_EEPROM * EEPROM read/write support 837 CONFIG_CMD_EEPROM_LAYOUT* EEPROM layout aware commands 838 CONFIG_CMD_ELF * bootelf, bootvx 839 CONFIG_CMD_ENV_CALLBACK * display details about env callbacks 840 CONFIG_CMD_ENV_FLAGS * display details about env flags 841 CONFIG_CMD_ENV_EXISTS * check existence of env variable 842 CONFIG_CMD_EXPORTENV * export the environment 843 CONFIG_CMD_EXT2 * ext2 command support 844 CONFIG_CMD_EXT4 * ext4 command support 845 CONFIG_CMD_FS_GENERIC * filesystem commands (e.g. load, ls) 846 that work for multiple fs types 847 CONFIG_CMD_FS_UUID * Look up a filesystem UUID 848 CONFIG_CMD_SAVEENV saveenv 849 CONFIG_CMD_FDC * Floppy Disk Support 850 CONFIG_CMD_FAT * FAT command support 851 CONFIG_CMD_FLASH flinfo, erase, protect 852 CONFIG_CMD_FPGA FPGA device initialization support 853 CONFIG_CMD_FUSE * Device fuse support 854 CONFIG_CMD_GETTIME * Get time since boot 855 CONFIG_CMD_GO * the 'go' command (exec code) 856 CONFIG_CMD_GREPENV * search environment 857 CONFIG_CMD_HASH * calculate hash / digest 858 CONFIG_CMD_I2C * I2C serial bus support 859 CONFIG_CMD_IDE * IDE harddisk support 860 CONFIG_CMD_IMI iminfo 861 CONFIG_CMD_IMLS List all images found in NOR flash 862 CONFIG_CMD_IMLS_NAND * List all images found in NAND flash 863 CONFIG_CMD_IMMAP * IMMR dump support 864 CONFIG_CMD_IOTRACE * I/O tracing for debugging 865 CONFIG_CMD_IMPORTENV * import an environment 866 CONFIG_CMD_INI * import data from an ini file into the env 867 CONFIG_CMD_IRQ * irqinfo 868 CONFIG_CMD_ITEST Integer/string test of 2 values 869 CONFIG_CMD_JFFS2 * JFFS2 Support 870 CONFIG_CMD_KGDB * kgdb 871 CONFIG_CMD_LDRINFO * ldrinfo (display Blackfin loader) 872 CONFIG_CMD_LINK_LOCAL * link-local IP address auto-configuration 873 (169.254.*.*) 874 CONFIG_CMD_LOADB loadb 875 CONFIG_CMD_LOADS loads 876 CONFIG_CMD_MD5SUM * print md5 message digest 877 (requires CONFIG_CMD_MEMORY and CONFIG_MD5) 878 CONFIG_CMD_MEMINFO * Display detailed memory information 879 CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base, 880 loop, loopw 881 CONFIG_CMD_MEMTEST * mtest 882 CONFIG_CMD_MISC Misc functions like sleep etc 883 CONFIG_CMD_MMC * MMC memory mapped support 884 CONFIG_CMD_MII * MII utility commands 885 CONFIG_CMD_MTDPARTS * MTD partition support 886 CONFIG_CMD_NAND * NAND support 887 CONFIG_CMD_NET bootp, tftpboot, rarpboot 888 CONFIG_CMD_NFS NFS support 889 CONFIG_CMD_PCA953X * PCA953x I2C gpio commands 890 CONFIG_CMD_PCA953X_INFO * PCA953x I2C gpio info command 891 CONFIG_CMD_PCI * pciinfo 892 CONFIG_CMD_PCMCIA * PCMCIA support 893 CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network 894 host 895 CONFIG_CMD_PORTIO * Port I/O 896 CONFIG_CMD_READ * Read raw data from partition 897 CONFIG_CMD_REGINFO * Register dump 898 CONFIG_CMD_RUN run command in env variable 899 CONFIG_CMD_SANDBOX * sb command to access sandbox features 900 CONFIG_CMD_SAVES * save S record dump 901 CONFIG_SCSI * SCSI Support 902 CONFIG_CMD_SDRAM * print SDRAM configuration information 903 (requires CONFIG_CMD_I2C) 904 CONFIG_CMD_SETGETDCR Support for DCR Register access 905 (4xx only) 906 CONFIG_CMD_SF * Read/write/erase SPI NOR flash 907 CONFIG_CMD_SHA1SUM * print sha1 memory digest 908 (requires CONFIG_CMD_MEMORY) 909 CONFIG_CMD_SOFTSWITCH * Soft switch setting command for BF60x 910 CONFIG_CMD_SOURCE "source" command Support 911 CONFIG_CMD_SPI * SPI serial bus support 912 CONFIG_CMD_TFTPSRV * TFTP transfer in server mode 913 CONFIG_CMD_TFTPPUT * TFTP put command (upload) 914 CONFIG_CMD_TIME * run command and report execution time (ARM specific) 915 CONFIG_CMD_TIMER * access to the system tick timer 916 CONFIG_CMD_USB * USB support 917 CONFIG_CMD_CDP * Cisco Discover Protocol support 918 CONFIG_CMD_MFSL * Microblaze FSL support 919 CONFIG_CMD_XIMG Load part of Multi Image 920 CONFIG_CMD_UUID * Generate random UUID or GUID string 921 922 EXAMPLE: If you want all functions except of network 923 support you can write: 924 925 #include "config_cmd_all.h" 926 #undef CONFIG_CMD_NET 927 928 Other Commands: 929 fdt (flattened device tree) command: CONFIG_OF_LIBFDT 930 931 Note: Don't enable the "icache" and "dcache" commands 932 (configuration option CONFIG_CMD_CACHE) unless you know 933 what you (and your U-Boot users) are doing. Data 934 cache cannot be enabled on systems like the 8xx or 935 8260 (where accesses to the IMMR region must be 936 uncached), and it cannot be disabled on all other 937 systems where we (mis-) use the data cache to hold an 938 initial stack and some data. 939 940 941 XXX - this list needs to get updated! 942 943- Removal of commands 944 If no commands are needed to boot, you can disable 945 CONFIG_CMDLINE to remove them. In this case, the command line 946 will not be available, and when U-Boot wants to execute the 947 boot command (on start-up) it will call board_run_command() 948 instead. This can reduce image size significantly for very 949 simple boot procedures. 950 951- Regular expression support: 952 CONFIG_REGEX 953 If this variable is defined, U-Boot is linked against 954 the SLRE (Super Light Regular Expression) library, 955 which adds regex support to some commands, as for 956 example "env grep" and "setexpr". 957 958- Device tree: 959 CONFIG_OF_CONTROL 960 If this variable is defined, U-Boot will use a device tree 961 to configure its devices, instead of relying on statically 962 compiled #defines in the board file. This option is 963 experimental and only available on a few boards. The device 964 tree is available in the global data as gd->fdt_blob. 965 966 U-Boot needs to get its device tree from somewhere. This can 967 be done using one of the three options below: 968 969 CONFIG_OF_EMBED 970 If this variable is defined, U-Boot will embed a device tree 971 binary in its image. This device tree file should be in the 972 board directory and called <soc>-<board>.dts. The binary file 973 is then picked up in board_init_f() and made available through 974 the global data structure as gd->blob. 975 976 CONFIG_OF_SEPARATE 977 If this variable is defined, U-Boot will build a device tree 978 binary. It will be called u-boot.dtb. Architecture-specific 979 code will locate it at run-time. Generally this works by: 980 981 cat u-boot.bin u-boot.dtb >image.bin 982 983 and in fact, U-Boot does this for you, creating a file called 984 u-boot-dtb.bin which is useful in the common case. You can 985 still use the individual files if you need something more 986 exotic. 987 988 CONFIG_OF_BOARD 989 If this variable is defined, U-Boot will use the device tree 990 provided by the board at runtime instead of embedding one with 991 the image. Only boards defining board_fdt_blob_setup() support 992 this option (see include/fdtdec.h file). 993 994- Watchdog: 995 CONFIG_WATCHDOG 996 If this variable is defined, it enables watchdog 997 support for the SoC. There must be support in the SoC 998 specific code for a watchdog. For the 8xx and 8260 999 CPUs, the SIU Watchdog feature is enabled in the SYPCR 1000 register. When supported for a specific SoC is 1001 available, then no further board specific code should 1002 be needed to use it. 1003 1004 CONFIG_HW_WATCHDOG 1005 When using a watchdog circuitry external to the used 1006 SoC, then define this variable and provide board 1007 specific code for the "hw_watchdog_reset" function. 1008 1009 CONFIG_AT91_HW_WDT_TIMEOUT 1010 specify the timeout in seconds. default 2 seconds. 1011 1012- U-Boot Version: 1013 CONFIG_VERSION_VARIABLE 1014 If this variable is defined, an environment variable 1015 named "ver" is created by U-Boot showing the U-Boot 1016 version as printed by the "version" command. 1017 Any change to this variable will be reverted at the 1018 next reset. 1019 1020- Real-Time Clock: 1021 1022 When CONFIG_CMD_DATE is selected, the type of the RTC 1023 has to be selected, too. Define exactly one of the 1024 following options: 1025 1026 CONFIG_RTC_MPC8xx - use internal RTC of MPC8xx 1027 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 1028 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 1029 CONFIG_RTC_MC146818 - use MC146818 RTC 1030 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 1031 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 1032 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 1033 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 1034 CONFIG_RTC_DS164x - use Dallas DS164x RTC 1035 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 1036 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 1037 CONFIG_SYS_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 1038 CONFIG_SYS_RV3029_TCR - enable trickle charger on 1039 RV3029 RTC. 1040 1041 Note that if the RTC uses I2C, then the I2C interface 1042 must also be configured. See I2C Support, below. 1043 1044- GPIO Support: 1045 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 1046 1047 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 1048 chip-ngpio pairs that tell the PCA953X driver the number of 1049 pins supported by a particular chip. 1050 1051 Note that if the GPIO device uses I2C, then the I2C interface 1052 must also be configured. See I2C Support, below. 1053 1054- I/O tracing: 1055 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 1056 accesses and can checksum them or write a list of them out 1057 to memory. See the 'iotrace' command for details. This is 1058 useful for testing device drivers since it can confirm that 1059 the driver behaves the same way before and after a code 1060 change. Currently this is supported on sandbox and arm. To 1061 add support for your architecture, add '#include <iotrace.h>' 1062 to the bottom of arch/<arch>/include/asm/io.h and test. 1063 1064 Example output from the 'iotrace stats' command is below. 1065 Note that if the trace buffer is exhausted, the checksum will 1066 still continue to operate. 1067 1068 iotrace is enabled 1069 Start: 10000000 (buffer start address) 1070 Size: 00010000 (buffer size) 1071 Offset: 00000120 (current buffer offset) 1072 Output: 10000120 (start + offset) 1073 Count: 00000018 (number of trace records) 1074 CRC32: 9526fb66 (CRC32 of all trace records) 1075 1076- Timestamp Support: 1077 1078 When CONFIG_TIMESTAMP is selected, the timestamp 1079 (date and time) of an image is printed by image 1080 commands like bootm or iminfo. This option is 1081 automatically enabled when you select CONFIG_CMD_DATE . 1082 1083- Partition Labels (disklabels) Supported: 1084 Zero or more of the following: 1085 CONFIG_MAC_PARTITION Apple's MacOS partition table. 1086 CONFIG_DOS_PARTITION MS Dos partition table, traditional on the 1087 Intel architecture, USB sticks, etc. 1088 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 1089 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 1090 bootloader. Note 2TB partition limit; see 1091 disk/part_efi.c 1092 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 1093 1094 If IDE or SCSI support is enabled (CONFIG_CMD_IDE or 1095 CONFIG_SCSI) you must configure support for at 1096 least one non-MTD partition type as well. 1097 1098- IDE Reset method: 1099 CONFIG_IDE_RESET_ROUTINE - this is defined in several 1100 board configurations files but used nowhere! 1101 1102 CONFIG_IDE_RESET - is this is defined, IDE Reset will 1103 be performed by calling the function 1104 ide_set_reset(int reset) 1105 which has to be defined in a board specific file 1106 1107- ATAPI Support: 1108 CONFIG_ATAPI 1109 1110 Set this to enable ATAPI support. 1111 1112- LBA48 Support 1113 CONFIG_LBA48 1114 1115 Set this to enable support for disks larger than 137GB 1116 Also look at CONFIG_SYS_64BIT_LBA. 1117 Whithout these , LBA48 support uses 32bit variables and will 'only' 1118 support disks up to 2.1TB. 1119 1120 CONFIG_SYS_64BIT_LBA: 1121 When enabled, makes the IDE subsystem use 64bit sector addresses. 1122 Default is 32bit. 1123 1124- SCSI Support: 1125 At the moment only there is only support for the 1126 SYM53C8XX SCSI controller; define 1127 CONFIG_SCSI_SYM53C8XX to enable it. 1128 1129 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 1130 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 1131 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 1132 maximum numbers of LUNs, SCSI ID's and target 1133 devices. 1134 CONFIG_SYS_SCSI_SYM53C8XX_CCF to fix clock timing (80Mhz) 1135 1136 The environment variable 'scsidevs' is set to the number of 1137 SCSI devices found during the last scan. 1138 1139- NETWORK Support (PCI): 1140 CONFIG_E1000 1141 Support for Intel 8254x/8257x gigabit chips. 1142 1143 CONFIG_E1000_SPI 1144 Utility code for direct access to the SPI bus on Intel 8257x. 1145 This does not do anything useful unless you set at least one 1146 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 1147 1148 CONFIG_E1000_SPI_GENERIC 1149 Allow generic access to the SPI bus on the Intel 8257x, for 1150 example with the "sspi" command. 1151 1152 CONFIG_CMD_E1000 1153 Management command for E1000 devices. When used on devices 1154 with SPI support you can reprogram the EEPROM from U-Boot. 1155 1156 CONFIG_EEPRO100 1157 Support for Intel 82557/82559/82559ER chips. 1158 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 1159 write routine for first time initialisation. 1160 1161 CONFIG_TULIP 1162 Support for Digital 2114x chips. 1163 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 1164 modem chip initialisation (KS8761/QS6611). 1165 1166 CONFIG_NATSEMI 1167 Support for National dp83815 chips. 1168 1169 CONFIG_NS8382X 1170 Support for National dp8382[01] gigabit chips. 1171 1172- NETWORK Support (other): 1173 1174 CONFIG_DRIVER_AT91EMAC 1175 Support for AT91RM9200 EMAC. 1176 1177 CONFIG_RMII 1178 Define this to use reduced MII inteface 1179 1180 CONFIG_DRIVER_AT91EMAC_QUIET 1181 If this defined, the driver is quiet. 1182 The driver doen't show link status messages. 1183 1184 CONFIG_CALXEDA_XGMAC 1185 Support for the Calxeda XGMAC device 1186 1187 CONFIG_LAN91C96 1188 Support for SMSC's LAN91C96 chips. 1189 1190 CONFIG_LAN91C96_USE_32_BIT 1191 Define this to enable 32 bit addressing 1192 1193 CONFIG_SMC91111 1194 Support for SMSC's LAN91C111 chip 1195 1196 CONFIG_SMC91111_BASE 1197 Define this to hold the physical address 1198 of the device (I/O space) 1199 1200 CONFIG_SMC_USE_32_BIT 1201 Define this if data bus is 32 bits 1202 1203 CONFIG_SMC_USE_IOFUNCS 1204 Define this to use i/o functions instead of macros 1205 (some hardware wont work with macros) 1206 1207 CONFIG_DRIVER_TI_EMAC 1208 Support for davinci emac 1209 1210 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1211 Define this if you have more then 3 PHYs. 1212 1213 CONFIG_FTGMAC100 1214 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1215 1216 CONFIG_FTGMAC100_EGIGA 1217 Define this to use GE link update with gigabit PHY. 1218 Define this if FTGMAC100 is connected to gigabit PHY. 1219 If your system has 10/100 PHY only, it might not occur 1220 wrong behavior. Because PHY usually return timeout or 1221 useless data when polling gigabit status and gigabit 1222 control registers. This behavior won't affect the 1223 correctnessof 10/100 link speed update. 1224 1225 CONFIG_SMC911X 1226 Support for SMSC's LAN911x and LAN921x chips 1227 1228 CONFIG_SMC911X_BASE 1229 Define this to hold the physical address 1230 of the device (I/O space) 1231 1232 CONFIG_SMC911X_32_BIT 1233 Define this if data bus is 32 bits 1234 1235 CONFIG_SMC911X_16_BIT 1236 Define this if data bus is 16 bits. If your processor 1237 automatically converts one 32 bit word to two 16 bit 1238 words you may also try CONFIG_SMC911X_32_BIT. 1239 1240 CONFIG_SH_ETHER 1241 Support for Renesas on-chip Ethernet controller 1242 1243 CONFIG_SH_ETHER_USE_PORT 1244 Define the number of ports to be used 1245 1246 CONFIG_SH_ETHER_PHY_ADDR 1247 Define the ETH PHY's address 1248 1249 CONFIG_SH_ETHER_CACHE_WRITEBACK 1250 If this option is set, the driver enables cache flush. 1251 1252- PWM Support: 1253 CONFIG_PWM_IMX 1254 Support for PWM module on the imx6. 1255 1256- TPM Support: 1257 CONFIG_TPM 1258 Support TPM devices. 1259 1260 CONFIG_TPM_TIS_INFINEON 1261 Support for Infineon i2c bus TPM devices. Only one device 1262 per system is supported at this time. 1263 1264 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1265 Define the burst count bytes upper limit 1266 1267 CONFIG_TPM_ST33ZP24 1268 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1269 1270 CONFIG_TPM_ST33ZP24_I2C 1271 Support for STMicroelectronics ST33ZP24 I2C devices. 1272 Requires TPM_ST33ZP24 and I2C. 1273 1274 CONFIG_TPM_ST33ZP24_SPI 1275 Support for STMicroelectronics ST33ZP24 SPI devices. 1276 Requires TPM_ST33ZP24 and SPI. 1277 1278 CONFIG_TPM_ATMEL_TWI 1279 Support for Atmel TWI TPM device. Requires I2C support. 1280 1281 CONFIG_TPM_TIS_LPC 1282 Support for generic parallel port TPM devices. Only one device 1283 per system is supported at this time. 1284 1285 CONFIG_TPM_TIS_BASE_ADDRESS 1286 Base address where the generic TPM device is mapped 1287 to. Contemporary x86 systems usually map it at 1288 0xfed40000. 1289 1290 CONFIG_CMD_TPM 1291 Add tpm monitor functions. 1292 Requires CONFIG_TPM. If CONFIG_TPM_AUTH_SESSIONS is set, also 1293 provides monitor access to authorized functions. 1294 1295 CONFIG_TPM 1296 Define this to enable the TPM support library which provides 1297 functional interfaces to some TPM commands. 1298 Requires support for a TPM device. 1299 1300 CONFIG_TPM_AUTH_SESSIONS 1301 Define this to enable authorized functions in the TPM library. 1302 Requires CONFIG_TPM and CONFIG_SHA1. 1303 1304- USB Support: 1305 At the moment only the UHCI host controller is 1306 supported (PIP405, MIP405, MPC5200); define 1307 CONFIG_USB_UHCI to enable it. 1308 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1309 and define CONFIG_USB_STORAGE to enable the USB 1310 storage devices. 1311 Note: 1312 Supported are USB Keyboards and USB Floppy drives 1313 (TEAC FD-05PUB). 1314 MPC5200 USB requires additional defines: 1315 CONFIG_USB_CLOCK 1316 for 528 MHz Clock: 0x0001bbbb 1317 CONFIG_PSC3_USB 1318 for USB on PSC3 1319 CONFIG_USB_CONFIG 1320 for differential drivers: 0x00001000 1321 for single ended drivers: 0x00005000 1322 for differential drivers on PSC3: 0x00000100 1323 for single ended drivers on PSC3: 0x00004100 1324 CONFIG_SYS_USB_EVENT_POLL 1325 May be defined to allow interrupt polling 1326 instead of using asynchronous interrupts 1327 1328 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1329 txfilltuning field in the EHCI controller on reset. 1330 1331 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1332 HW module registers. 1333 1334- USB Device: 1335 Define the below if you wish to use the USB console. 1336 Once firmware is rebuilt from a serial console issue the 1337 command "setenv stdin usbtty; setenv stdout usbtty" and 1338 attach your USB cable. The Unix command "dmesg" should print 1339 it has found a new device. The environment variable usbtty 1340 can be set to gserial or cdc_acm to enable your device to 1341 appear to a USB host as a Linux gserial device or a 1342 Common Device Class Abstract Control Model serial device. 1343 If you select usbtty = gserial you should be able to enumerate 1344 a Linux host by 1345 # modprobe usbserial vendor=0xVendorID product=0xProductID 1346 else if using cdc_acm, simply setting the environment 1347 variable usbtty to be cdc_acm should suffice. The following 1348 might be defined in YourBoardName.h 1349 1350 CONFIG_USB_DEVICE 1351 Define this to build a UDC device 1352 1353 CONFIG_USB_TTY 1354 Define this to have a tty type of device available to 1355 talk to the UDC device 1356 1357 CONFIG_USBD_HS 1358 Define this to enable the high speed support for usb 1359 device and usbtty. If this feature is enabled, a routine 1360 int is_usbd_high_speed(void) 1361 also needs to be defined by the driver to dynamically poll 1362 whether the enumeration has succeded at high speed or full 1363 speed. 1364 1365 CONFIG_SYS_CONSOLE_IS_IN_ENV 1366 Define this if you want stdin, stdout &/or stderr to 1367 be set to usbtty. 1368 1369 mpc8xx: 1370 CONFIG_SYS_USB_EXTC_CLK 0xBLAH 1371 Derive USB clock from external clock "blah" 1372 - CONFIG_SYS_USB_EXTC_CLK 0x02 1373 1374 If you have a USB-IF assigned VendorID then you may wish to 1375 define your own vendor specific values either in BoardName.h 1376 or directly in usbd_vendor_info.h. If you don't define 1377 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1378 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1379 should pretend to be a Linux device to it's target host. 1380 1381 CONFIG_USBD_MANUFACTURER 1382 Define this string as the name of your company for 1383 - CONFIG_USBD_MANUFACTURER "my company" 1384 1385 CONFIG_USBD_PRODUCT_NAME 1386 Define this string as the name of your product 1387 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1388 1389 CONFIG_USBD_VENDORID 1390 Define this as your assigned Vendor ID from the USB 1391 Implementors Forum. This *must* be a genuine Vendor ID 1392 to avoid polluting the USB namespace. 1393 - CONFIG_USBD_VENDORID 0xFFFF 1394 1395 CONFIG_USBD_PRODUCTID 1396 Define this as the unique Product ID 1397 for your device 1398 - CONFIG_USBD_PRODUCTID 0xFFFF 1399 1400- ULPI Layer Support: 1401 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1402 the generic ULPI layer. The generic layer accesses the ULPI PHY 1403 via the platform viewport, so you need both the genric layer and 1404 the viewport enabled. Currently only Chipidea/ARC based 1405 viewport is supported. 1406 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1407 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1408 If your ULPI phy needs a different reference clock than the 1409 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1410 the appropriate value in Hz. 1411 1412- MMC Support: 1413 The MMC controller on the Intel PXA is supported. To 1414 enable this define CONFIG_MMC. The MMC can be 1415 accessed from the boot prompt by mapping the device 1416 to physical memory similar to flash. Command line is 1417 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1418 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1419 1420 CONFIG_SH_MMCIF 1421 Support for Renesas on-chip MMCIF controller 1422 1423 CONFIG_SH_MMCIF_ADDR 1424 Define the base address of MMCIF registers 1425 1426 CONFIG_SH_MMCIF_CLK 1427 Define the clock frequency for MMCIF 1428 1429 CONFIG_SUPPORT_EMMC_BOOT 1430 Enable some additional features of the eMMC boot partitions. 1431 1432 CONFIG_SUPPORT_EMMC_RPMB 1433 Enable the commands for reading, writing and programming the 1434 key for the Replay Protection Memory Block partition in eMMC. 1435 1436- USB Device Firmware Update (DFU) class support: 1437 CONFIG_USB_FUNCTION_DFU 1438 This enables the USB portion of the DFU USB class 1439 1440 CONFIG_CMD_DFU 1441 This enables the command "dfu" which is used to have 1442 U-Boot create a DFU class device via USB. This command 1443 requires that the "dfu_alt_info" environment variable be 1444 set and define the alt settings to expose to the host. 1445 1446 CONFIG_DFU_MMC 1447 This enables support for exposing (e)MMC devices via DFU. 1448 1449 CONFIG_DFU_NAND 1450 This enables support for exposing NAND devices via DFU. 1451 1452 CONFIG_DFU_RAM 1453 This enables support for exposing RAM via DFU. 1454 Note: DFU spec refer to non-volatile memory usage, but 1455 allow usages beyond the scope of spec - here RAM usage, 1456 one that would help mostly the developer. 1457 1458 CONFIG_SYS_DFU_DATA_BUF_SIZE 1459 Dfu transfer uses a buffer before writing data to the 1460 raw storage device. Make the size (in bytes) of this buffer 1461 configurable. The size of this buffer is also configurable 1462 through the "dfu_bufsiz" environment variable. 1463 1464 CONFIG_SYS_DFU_MAX_FILE_SIZE 1465 When updating files rather than the raw storage device, 1466 we use a static buffer to copy the file into and then write 1467 the buffer once we've been given the whole file. Define 1468 this to the maximum filesize (in bytes) for the buffer. 1469 Default is 4 MiB if undefined. 1470 1471 DFU_DEFAULT_POLL_TIMEOUT 1472 Poll timeout [ms], is the timeout a device can send to the 1473 host. The host must wait for this timeout before sending 1474 a subsequent DFU_GET_STATUS request to the device. 1475 1476 DFU_MANIFEST_POLL_TIMEOUT 1477 Poll timeout [ms], which the device sends to the host when 1478 entering dfuMANIFEST state. Host waits this timeout, before 1479 sending again an USB request to the device. 1480 1481- USB Device Android Fastboot support: 1482 CONFIG_USB_FUNCTION_FASTBOOT 1483 This enables the USB part of the fastboot gadget 1484 1485 CONFIG_CMD_FASTBOOT 1486 This enables the command "fastboot" which enables the Android 1487 fastboot mode for the platform's USB device. Fastboot is a USB 1488 protocol for downloading images, flashing and device control 1489 used on Android devices. 1490 See doc/README.android-fastboot for more information. 1491 1492 CONFIG_ANDROID_BOOT_IMAGE 1493 This enables support for booting images which use the Android 1494 image format header. 1495 1496 CONFIG_FASTBOOT_BUF_ADDR 1497 The fastboot protocol requires a large memory buffer for 1498 downloads. Define this to the starting RAM address to use for 1499 downloaded images. 1500 1501 CONFIG_FASTBOOT_BUF_SIZE 1502 The fastboot protocol requires a large memory buffer for 1503 downloads. This buffer should be as large as possible for a 1504 platform. Define this to the size available RAM for fastboot. 1505 1506 CONFIG_FASTBOOT_FLASH 1507 The fastboot protocol includes a "flash" command for writing 1508 the downloaded image to a non-volatile storage device. Define 1509 this to enable the "fastboot flash" command. 1510 1511 CONFIG_FASTBOOT_FLASH_MMC_DEV 1512 The fastboot "flash" command requires additional information 1513 regarding the non-volatile storage device. Define this to 1514 the eMMC device that fastboot should use to store the image. 1515 1516 CONFIG_FASTBOOT_GPT_NAME 1517 The fastboot "flash" command supports writing the downloaded 1518 image to the Protective MBR and the Primary GUID Partition 1519 Table. (Additionally, this downloaded image is post-processed 1520 to generate and write the Backup GUID Partition Table.) 1521 This occurs when the specified "partition name" on the 1522 "fastboot flash" command line matches this value. 1523 The default is "gpt" if undefined. 1524 1525 CONFIG_FASTBOOT_MBR_NAME 1526 The fastboot "flash" command supports writing the downloaded 1527 image to DOS MBR. 1528 This occurs when the "partition name" specified on the 1529 "fastboot flash" command line matches this value. 1530 If not defined the default value "mbr" is used. 1531 1532- Journaling Flash filesystem support: 1533 CONFIG_JFFS2_NAND 1534 Define these for a default partition on a NAND device 1535 1536 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1537 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1538 Define these for a default partition on a NOR device 1539 1540- FAT(File Allocation Table) filesystem write function support: 1541 CONFIG_FAT_WRITE 1542 1543 Define this to enable support for saving memory data as a 1544 file in FAT formatted partition. 1545 1546 This will also enable the command "fatwrite" enabling the 1547 user to write files to FAT. 1548 1549- FAT(File Allocation Table) filesystem cluster size: 1550 CONFIG_FS_FAT_MAX_CLUSTSIZE 1551 1552 Define the max cluster size for fat operations else 1553 a default value of 65536 will be defined. 1554 1555- Keyboard Support: 1556 See Kconfig help for available keyboard drivers. 1557 1558 CONFIG_KEYBOARD 1559 1560 Define this to enable a custom keyboard support. 1561 This simply calls drv_keyboard_init() which must be 1562 defined in your board-specific files. This option is deprecated 1563 and is only used by novena. For new boards, use driver model 1564 instead. 1565 1566- Video support: 1567 CONFIG_FSL_DIU_FB 1568 Enable the Freescale DIU video driver. Reference boards for 1569 SOCs that have a DIU should define this macro to enable DIU 1570 support, and should also define these other macros: 1571 1572 CONFIG_SYS_DIU_ADDR 1573 CONFIG_VIDEO 1574 CONFIG_CFB_CONSOLE 1575 CONFIG_VIDEO_SW_CURSOR 1576 CONFIG_VGA_AS_SINGLE_DEVICE 1577 CONFIG_VIDEO_LOGO 1578 CONFIG_VIDEO_BMP_LOGO 1579 1580 The DIU driver will look for the 'video-mode' environment 1581 variable, and if defined, enable the DIU as a console during 1582 boot. See the documentation file doc/README.video for a 1583 description of this variable. 1584 1585- LCD Support: CONFIG_LCD 1586 1587 Define this to enable LCD support (for output to LCD 1588 display); also select one of the supported displays 1589 by defining one of these: 1590 1591 CONFIG_ATMEL_LCD: 1592 1593 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1594 1595 CONFIG_NEC_NL6448AC33: 1596 1597 NEC NL6448AC33-18. Active, color, single scan. 1598 1599 CONFIG_NEC_NL6448BC20 1600 1601 NEC NL6448BC20-08. 6.5", 640x480. 1602 Active, color, single scan. 1603 1604 CONFIG_NEC_NL6448BC33_54 1605 1606 NEC NL6448BC33-54. 10.4", 640x480. 1607 Active, color, single scan. 1608 1609 CONFIG_SHARP_16x9 1610 1611 Sharp 320x240. Active, color, single scan. 1612 It isn't 16x9, and I am not sure what it is. 1613 1614 CONFIG_SHARP_LQ64D341 1615 1616 Sharp LQ64D341 display, 640x480. 1617 Active, color, single scan. 1618 1619 CONFIG_HLD1045 1620 1621 HLD1045 display, 640x480. 1622 Active, color, single scan. 1623 1624 CONFIG_OPTREX_BW 1625 1626 Optrex CBL50840-2 NF-FW 99 22 M5 1627 or 1628 Hitachi LMG6912RPFC-00T 1629 or 1630 Hitachi SP14Q002 1631 1632 320x240. Black & white. 1633 1634 CONFIG_LCD_ALIGNMENT 1635 1636 Normally the LCD is page-aligned (typically 4KB). If this is 1637 defined then the LCD will be aligned to this value instead. 1638 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1639 here, since it is cheaper to change data cache settings on 1640 a per-section basis. 1641 1642 1643 CONFIG_LCD_ROTATION 1644 1645 Sometimes, for example if the display is mounted in portrait 1646 mode or even if it's mounted landscape but rotated by 180degree, 1647 we need to rotate our content of the display relative to the 1648 framebuffer, so that user can read the messages which are 1649 printed out. 1650 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1651 initialized with a given rotation from "vl_rot" out of 1652 "vidinfo_t" which is provided by the board specific code. 1653 The value for vl_rot is coded as following (matching to 1654 fbcon=rotate:<n> linux-kernel commandline): 1655 0 = no rotation respectively 0 degree 1656 1 = 90 degree rotation 1657 2 = 180 degree rotation 1658 3 = 270 degree rotation 1659 1660 If CONFIG_LCD_ROTATION is not defined, the console will be 1661 initialized with 0degree rotation. 1662 1663 CONFIG_LCD_BMP_RLE8 1664 1665 Support drawing of RLE8-compressed bitmaps on the LCD. 1666 1667 CONFIG_I2C_EDID 1668 1669 Enables an 'i2c edid' command which can read EDID 1670 information over I2C from an attached LCD display. 1671 1672- Splash Screen Support: CONFIG_SPLASH_SCREEN 1673 1674 If this option is set, the environment is checked for 1675 a variable "splashimage". If found, the usual display 1676 of logo, copyright and system information on the LCD 1677 is suppressed and the BMP image at the address 1678 specified in "splashimage" is loaded instead. The 1679 console is redirected to the "nulldev", too. This 1680 allows for a "silent" boot where a splash screen is 1681 loaded very quickly after power-on. 1682 1683 CONFIG_SPLASHIMAGE_GUARD 1684 1685 If this option is set, then U-Boot will prevent the environment 1686 variable "splashimage" from being set to a problematic address 1687 (see doc/README.displaying-bmps). 1688 This option is useful for targets where, due to alignment 1689 restrictions, an improperly aligned BMP image will cause a data 1690 abort. If you think you will not have problems with unaligned 1691 accesses (for example because your toolchain prevents them) 1692 there is no need to set this option. 1693 1694 CONFIG_SPLASH_SCREEN_ALIGN 1695 1696 If this option is set the splash image can be freely positioned 1697 on the screen. Environment variable "splashpos" specifies the 1698 position as "x,y". If a positive number is given it is used as 1699 number of pixel from left/top. If a negative number is given it 1700 is used as number of pixel from right/bottom. You can also 1701 specify 'm' for centering the image. 1702 1703 Example: 1704 setenv splashpos m,m 1705 => image at center of screen 1706 1707 setenv splashpos 30,20 1708 => image at x = 30 and y = 20 1709 1710 setenv splashpos -10,m 1711 => vertically centered image 1712 at x = dspWidth - bmpWidth - 9 1713 1714- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1715 1716 If this option is set, additionally to standard BMP 1717 images, gzipped BMP images can be displayed via the 1718 splashscreen support or the bmp command. 1719 1720- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1721 1722 If this option is set, 8-bit RLE compressed BMP images 1723 can be displayed via the splashscreen support or the 1724 bmp command. 1725 1726- Compression support: 1727 CONFIG_GZIP 1728 1729 Enabled by default to support gzip compressed images. 1730 1731 CONFIG_BZIP2 1732 1733 If this option is set, support for bzip2 compressed 1734 images is included. If not, only uncompressed and gzip 1735 compressed images are supported. 1736 1737 NOTE: the bzip2 algorithm requires a lot of RAM, so 1738 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1739 be at least 4MB. 1740 1741 CONFIG_LZMA 1742 1743 If this option is set, support for lzma compressed 1744 images is included. 1745 1746 Note: The LZMA algorithm adds between 2 and 4KB of code and it 1747 requires an amount of dynamic memory that is given by the 1748 formula: 1749 1750 (1846 + 768 << (lc + lp)) * sizeof(uint16) 1751 1752 Where lc and lp stand for, respectively, Literal context bits 1753 and Literal pos bits. 1754 1755 This value is upper-bounded by 14MB in the worst case. Anyway, 1756 for a ~4MB large kernel image, we have lc=3 and lp=0 for a 1757 total amount of (1846 + 768 << (3 + 0)) * 2 = ~41KB... that is 1758 a very small buffer. 1759 1760 Use the lzmainfo tool to determinate the lc and lp values and 1761 then calculate the amount of needed dynamic memory (ensuring 1762 the appropriate CONFIG_SYS_MALLOC_LEN value). 1763 1764 CONFIG_LZO 1765 1766 If this option is set, support for LZO compressed images 1767 is included. 1768 1769- MII/PHY support: 1770 CONFIG_PHY_ADDR 1771 1772 The address of PHY on MII bus. 1773 1774 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1775 1776 The clock frequency of the MII bus 1777 1778 CONFIG_PHY_GIGE 1779 1780 If this option is set, support for speed/duplex 1781 detection of gigabit PHY is included. 1782 1783 CONFIG_PHY_RESET_DELAY 1784 1785 Some PHY like Intel LXT971A need extra delay after 1786 reset before any MII register access is possible. 1787 For such PHY, set this option to the usec delay 1788 required. (minimum 300usec for LXT971A) 1789 1790 CONFIG_PHY_CMD_DELAY (ppc4xx) 1791 1792 Some PHY like Intel LXT971A need extra delay after 1793 command issued before MII status register can be read 1794 1795- IP address: 1796 CONFIG_IPADDR 1797 1798 Define a default value for the IP address to use for 1799 the default Ethernet interface, in case this is not 1800 determined through e.g. bootp. 1801 (Environment variable "ipaddr") 1802 1803- Server IP address: 1804 CONFIG_SERVERIP 1805 1806 Defines a default value for the IP address of a TFTP 1807 server to contact when using the "tftboot" command. 1808 (Environment variable "serverip") 1809 1810 CONFIG_KEEP_SERVERADDR 1811 1812 Keeps the server's MAC address, in the env 'serveraddr' 1813 for passing to bootargs (like Linux's netconsole option) 1814 1815- Gateway IP address: 1816 CONFIG_GATEWAYIP 1817 1818 Defines a default value for the IP address of the 1819 default router where packets to other networks are 1820 sent to. 1821 (Environment variable "gatewayip") 1822 1823- Subnet mask: 1824 CONFIG_NETMASK 1825 1826 Defines a default value for the subnet mask (or 1827 routing prefix) which is used to determine if an IP 1828 address belongs to the local subnet or needs to be 1829 forwarded through a router. 1830 (Environment variable "netmask") 1831 1832- Multicast TFTP Mode: 1833 CONFIG_MCAST_TFTP 1834 1835 Defines whether you want to support multicast TFTP as per 1836 rfc-2090; for example to work with atftp. Lets lots of targets 1837 tftp down the same boot image concurrently. Note: the Ethernet 1838 driver in use must provide a function: mcast() to join/leave a 1839 multicast group. 1840 1841- BOOTP Recovery Mode: 1842 CONFIG_BOOTP_RANDOM_DELAY 1843 1844 If you have many targets in a network that try to 1845 boot using BOOTP, you may want to avoid that all 1846 systems send out BOOTP requests at precisely the same 1847 moment (which would happen for instance at recovery 1848 from a power failure, when all systems will try to 1849 boot, thus flooding the BOOTP server. Defining 1850 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1851 inserted before sending out BOOTP requests. The 1852 following delays are inserted then: 1853 1854 1st BOOTP request: delay 0 ... 1 sec 1855 2nd BOOTP request: delay 0 ... 2 sec 1856 3rd BOOTP request: delay 0 ... 4 sec 1857 4th and following 1858 BOOTP requests: delay 0 ... 8 sec 1859 1860 CONFIG_BOOTP_ID_CACHE_SIZE 1861 1862 BOOTP packets are uniquely identified using a 32-bit ID. The 1863 server will copy the ID from client requests to responses and 1864 U-Boot will use this to determine if it is the destination of 1865 an incoming response. Some servers will check that addresses 1866 aren't in use before handing them out (usually using an ARP 1867 ping) and therefore take up to a few hundred milliseconds to 1868 respond. Network congestion may also influence the time it 1869 takes for a response to make it back to the client. If that 1870 time is too long, U-Boot will retransmit requests. In order 1871 to allow earlier responses to still be accepted after these 1872 retransmissions, U-Boot's BOOTP client keeps a small cache of 1873 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 1874 cache. The default is to keep IDs for up to four outstanding 1875 requests. Increasing this will allow U-Boot to accept offers 1876 from a BOOTP client in networks with unusually high latency. 1877 1878- DHCP Advanced Options: 1879 You can fine tune the DHCP functionality by defining 1880 CONFIG_BOOTP_* symbols: 1881 1882 CONFIG_BOOTP_SUBNETMASK 1883 CONFIG_BOOTP_GATEWAY 1884 CONFIG_BOOTP_HOSTNAME 1885 CONFIG_BOOTP_NISDOMAIN 1886 CONFIG_BOOTP_BOOTPATH 1887 CONFIG_BOOTP_BOOTFILESIZE 1888 CONFIG_BOOTP_DNS 1889 CONFIG_BOOTP_DNS2 1890 CONFIG_BOOTP_SEND_HOSTNAME 1891 CONFIG_BOOTP_NTPSERVER 1892 CONFIG_BOOTP_TIMEOFFSET 1893 CONFIG_BOOTP_VENDOREX 1894 CONFIG_BOOTP_MAY_FAIL 1895 1896 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1897 environment variable, not the BOOTP server. 1898 1899 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1900 after the configured retry count, the call will fail 1901 instead of starting over. This can be used to fail over 1902 to Link-local IP address configuration if the DHCP server 1903 is not available. 1904 1905 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1906 serverip from a DHCP server, it is possible that more 1907 than one DNS serverip is offered to the client. 1908 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1909 serverip will be stored in the additional environment 1910 variable "dnsip2". The first DNS serverip is always 1911 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1912 is defined. 1913 1914 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1915 to do a dynamic update of a DNS server. To do this, they 1916 need the hostname of the DHCP requester. 1917 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1918 of the "hostname" environment variable is passed as 1919 option 12 to the DHCP server. 1920 1921 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1922 1923 A 32bit value in microseconds for a delay between 1924 receiving a "DHCP Offer" and sending the "DHCP Request". 1925 This fixes a problem with certain DHCP servers that don't 1926 respond 100% of the time to a "DHCP request". E.g. On an 1927 AT91RM9200 processor running at 180MHz, this delay needed 1928 to be *at least* 15,000 usec before a Windows Server 2003 1929 DHCP server would reply 100% of the time. I recommend at 1930 least 50,000 usec to be safe. The alternative is to hope 1931 that one of the retries will be successful but note that 1932 the DHCP timeout and retry process takes a longer than 1933 this delay. 1934 1935 - Link-local IP address negotiation: 1936 Negotiate with other link-local clients on the local network 1937 for an address that doesn't require explicit configuration. 1938 This is especially useful if a DHCP server cannot be guaranteed 1939 to exist in all environments that the device must operate. 1940 1941 See doc/README.link-local for more information. 1942 1943 - CDP Options: 1944 CONFIG_CDP_DEVICE_ID 1945 1946 The device id used in CDP trigger frames. 1947 1948 CONFIG_CDP_DEVICE_ID_PREFIX 1949 1950 A two character string which is prefixed to the MAC address 1951 of the device. 1952 1953 CONFIG_CDP_PORT_ID 1954 1955 A printf format string which contains the ascii name of 1956 the port. Normally is set to "eth%d" which sets 1957 eth0 for the first Ethernet, eth1 for the second etc. 1958 1959 CONFIG_CDP_CAPABILITIES 1960 1961 A 32bit integer which indicates the device capabilities; 1962 0x00000010 for a normal host which does not forwards. 1963 1964 CONFIG_CDP_VERSION 1965 1966 An ascii string containing the version of the software. 1967 1968 CONFIG_CDP_PLATFORM 1969 1970 An ascii string containing the name of the platform. 1971 1972 CONFIG_CDP_TRIGGER 1973 1974 A 32bit integer sent on the trigger. 1975 1976 CONFIG_CDP_POWER_CONSUMPTION 1977 1978 A 16bit integer containing the power consumption of the 1979 device in .1 of milliwatts. 1980 1981 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1982 1983 A byte containing the id of the VLAN. 1984 1985- Status LED: CONFIG_LED_STATUS 1986 1987 Several configurations allow to display the current 1988 status using a LED. For instance, the LED will blink 1989 fast while running U-Boot code, stop blinking as 1990 soon as a reply to a BOOTP request was received, and 1991 start blinking slow once the Linux kernel is running 1992 (supported by a status LED driver in the Linux 1993 kernel). Defining CONFIG_LED_STATUS enables this 1994 feature in U-Boot. 1995 1996 Additional options: 1997 1998 CONFIG_LED_STATUS_GPIO 1999 The status LED can be connected to a GPIO pin. 2000 In such cases, the gpio_led driver can be used as a 2001 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO 2002 to include the gpio_led driver in the U-Boot binary. 2003 2004 CONFIG_GPIO_LED_INVERTED_TABLE 2005 Some GPIO connected LEDs may have inverted polarity in which 2006 case the GPIO high value corresponds to LED off state and 2007 GPIO low value corresponds to LED on state. 2008 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 2009 with a list of GPIO LEDs that have inverted polarity. 2010 2011- CAN Support: CONFIG_CAN_DRIVER 2012 2013 Defining CONFIG_CAN_DRIVER enables CAN driver support 2014 on those systems that support this (optional) 2015 feature, like the TQM8xxL modules. 2016 2017- I2C Support: CONFIG_SYS_I2C 2018 2019 This enable the NEW i2c subsystem, and will allow you to use 2020 i2c commands at the u-boot command line (as long as you set 2021 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 2022 based realtime clock chips or other i2c devices. See 2023 common/cmd_i2c.c for a description of the command line 2024 interface. 2025 2026 ported i2c driver to the new framework: 2027 - drivers/i2c/soft_i2c.c: 2028 - activate first bus with CONFIG_SYS_I2C_SOFT define 2029 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 2030 for defining speed and slave address 2031 - activate second bus with I2C_SOFT_DECLARATIONS2 define 2032 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 2033 for defining speed and slave address 2034 - activate third bus with I2C_SOFT_DECLARATIONS3 define 2035 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 2036 for defining speed and slave address 2037 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 2038 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 2039 for defining speed and slave address 2040 2041 - drivers/i2c/fsl_i2c.c: 2042 - activate i2c driver with CONFIG_SYS_I2C_FSL 2043 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 2044 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 2045 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 2046 bus. 2047 - If your board supports a second fsl i2c bus, define 2048 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 2049 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 2050 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 2051 second bus. 2052 2053 - drivers/i2c/tegra_i2c.c: 2054 - activate this driver with CONFIG_SYS_I2C_TEGRA 2055 - This driver adds 4 i2c buses with a fix speed from 2056 100000 and the slave addr 0! 2057 2058 - drivers/i2c/ppc4xx_i2c.c 2059 - activate this driver with CONFIG_SYS_I2C_PPC4XX 2060 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 2061 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 2062 2063 - drivers/i2c/i2c_mxc.c 2064 - activate this driver with CONFIG_SYS_I2C_MXC 2065 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 2066 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 2067 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 2068 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 2069 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 2070 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 2071 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 2072 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 2073 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 2074 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 2075 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 2076 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 2077 If those defines are not set, default value is 100000 2078 for speed, and 0 for slave. 2079 2080 - drivers/i2c/rcar_i2c.c: 2081 - activate this driver with CONFIG_SYS_I2C_RCAR 2082 - This driver adds 4 i2c buses 2083 2084 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 2085 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 2086 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 2087 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 2088 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 2089 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 2090 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 2091 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 2092 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 2093 2094 - drivers/i2c/sh_i2c.c: 2095 - activate this driver with CONFIG_SYS_I2C_SH 2096 - This driver adds from 2 to 5 i2c buses 2097 2098 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 2099 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 2100 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 2101 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 2102 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 2103 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 2104 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 2105 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 2106 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 2107 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 2108 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 2109 2110 - drivers/i2c/omap24xx_i2c.c 2111 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 2112 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 2113 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 2114 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 2115 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 2116 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 2117 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 2118 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 2119 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 2120 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 2121 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 2122 2123 - drivers/i2c/zynq_i2c.c 2124 - activate this driver with CONFIG_SYS_I2C_ZYNQ 2125 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 2126 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 2127 2128 - drivers/i2c/s3c24x0_i2c.c: 2129 - activate this driver with CONFIG_SYS_I2C_S3C24X0 2130 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 2131 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 2132 with a fix speed from 100000 and the slave addr 0! 2133 2134 - drivers/i2c/ihs_i2c.c 2135 - activate this driver with CONFIG_SYS_I2C_IHS 2136 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 2137 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 2138 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 2139 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 2140 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 2141 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 2142 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 2143 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 2144 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 2145 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 2146 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 2147 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 2148 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 2149 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 2150 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 2151 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 2152 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 2153 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 2154 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 2155 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 2156 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 2157 2158 additional defines: 2159 2160 CONFIG_SYS_NUM_I2C_BUSES 2161 Hold the number of i2c buses you want to use. 2162 2163 CONFIG_SYS_I2C_DIRECT_BUS 2164 define this, if you don't use i2c muxes on your hardware. 2165 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 2166 omit this define. 2167 2168 CONFIG_SYS_I2C_MAX_HOPS 2169 define how many muxes are maximal consecutively connected 2170 on one i2c bus. If you not use i2c muxes, omit this 2171 define. 2172 2173 CONFIG_SYS_I2C_BUSES 2174 hold a list of buses you want to use, only used if 2175 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 2176 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 2177 CONFIG_SYS_NUM_I2C_BUSES = 9: 2178 2179 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 2180 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 2181 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 2182 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 2183 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 2184 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 2185 {1, {I2C_NULL_HOP}}, \ 2186 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 2187 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 2188 } 2189 2190 which defines 2191 bus 0 on adapter 0 without a mux 2192 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 2193 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 2194 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 2195 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 2196 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 2197 bus 6 on adapter 1 without a mux 2198 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 2199 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 2200 2201 If you do not have i2c muxes on your board, omit this define. 2202 2203- Legacy I2C Support: 2204 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 2205 then the following macros need to be defined (examples are 2206 from include/configs/lwmon.h): 2207 2208 I2C_INIT 2209 2210 (Optional). Any commands necessary to enable the I2C 2211 controller or configure ports. 2212 2213 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 2214 2215 I2C_PORT 2216 2217 (Only for MPC8260 CPU). The I/O port to use (the code 2218 assumes both bits are on the same port). Valid values 2219 are 0..3 for ports A..D. 2220 2221 I2C_ACTIVE 2222 2223 The code necessary to make the I2C data line active 2224 (driven). If the data line is open collector, this 2225 define can be null. 2226 2227 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 2228 2229 I2C_TRISTATE 2230 2231 The code necessary to make the I2C data line tri-stated 2232 (inactive). If the data line is open collector, this 2233 define can be null. 2234 2235 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 2236 2237 I2C_READ 2238 2239 Code that returns true if the I2C data line is high, 2240 false if it is low. 2241 2242 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 2243 2244 I2C_SDA(bit) 2245 2246 If <bit> is true, sets the I2C data line high. If it 2247 is false, it clears it (low). 2248 2249 eg: #define I2C_SDA(bit) \ 2250 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 2251 else immr->im_cpm.cp_pbdat &= ~PB_SDA 2252 2253 I2C_SCL(bit) 2254 2255 If <bit> is true, sets the I2C clock line high. If it 2256 is false, it clears it (low). 2257 2258 eg: #define I2C_SCL(bit) \ 2259 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 2260 else immr->im_cpm.cp_pbdat &= ~PB_SCL 2261 2262 I2C_DELAY 2263 2264 This delay is invoked four times per clock cycle so this 2265 controls the rate of data transfer. The data rate thus 2266 is 1 / (I2C_DELAY * 4). Often defined to be something 2267 like: 2268 2269 #define I2C_DELAY udelay(2) 2270 2271 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 2272 2273 If your arch supports the generic GPIO framework (asm/gpio.h), 2274 then you may alternatively define the two GPIOs that are to be 2275 used as SCL / SDA. Any of the previous I2C_xxx macros will 2276 have GPIO-based defaults assigned to them as appropriate. 2277 2278 You should define these to the GPIO value as given directly to 2279 the generic GPIO functions. 2280 2281 CONFIG_SYS_I2C_INIT_BOARD 2282 2283 When a board is reset during an i2c bus transfer 2284 chips might think that the current transfer is still 2285 in progress. On some boards it is possible to access 2286 the i2c SCLK line directly, either by using the 2287 processor pin as a GPIO or by having a second pin 2288 connected to the bus. If this option is defined a 2289 custom i2c_init_board() routine in boards/xxx/board.c 2290 is run early in the boot sequence. 2291 2292 CONFIG_I2C_MULTI_BUS 2293 2294 This option allows the use of multiple I2C buses, each of which 2295 must have a controller. At any point in time, only one bus is 2296 active. To switch to a different bus, use the 'i2c dev' command. 2297 Note that bus numbering is zero-based. 2298 2299 CONFIG_SYS_I2C_NOPROBES 2300 2301 This option specifies a list of I2C devices that will be skipped 2302 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 2303 is set, specify a list of bus-device pairs. Otherwise, specify 2304 a 1D array of device addresses 2305 2306 e.g. 2307 #undef CONFIG_I2C_MULTI_BUS 2308 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 2309 2310 will skip addresses 0x50 and 0x68 on a board with one I2C bus 2311 2312 #define CONFIG_I2C_MULTI_BUS 2313 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 2314 2315 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 2316 2317 CONFIG_SYS_SPD_BUS_NUM 2318 2319 If defined, then this indicates the I2C bus number for DDR SPD. 2320 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 2321 2322 CONFIG_SYS_RTC_BUS_NUM 2323 2324 If defined, then this indicates the I2C bus number for the RTC. 2325 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 2326 2327 CONFIG_SYS_DTT_BUS_NUM 2328 2329 If defined, then this indicates the I2C bus number for the DTT. 2330 If not defined, then U-Boot assumes that DTT is on I2C bus 0. 2331 2332 CONFIG_SOFT_I2C_READ_REPEATED_START 2333 2334 defining this will force the i2c_read() function in 2335 the soft_i2c driver to perform an I2C repeated start 2336 between writing the address pointer and reading the 2337 data. If this define is omitted the default behaviour 2338 of doing a stop-start sequence will be used. Most I2C 2339 devices can use either method, but some require one or 2340 the other. 2341 2342- SPI Support: CONFIG_SPI 2343 2344 Enables SPI driver (so far only tested with 2345 SPI EEPROM, also an instance works with Crystal A/D and 2346 D/As on the SACSng board) 2347 2348 CONFIG_SH_SPI 2349 2350 Enables the driver for SPI controller on SuperH. Currently 2351 only SH7757 is supported. 2352 2353 CONFIG_SOFT_SPI 2354 2355 Enables a software (bit-bang) SPI driver rather than 2356 using hardware support. This is a general purpose 2357 driver that only requires three general I/O port pins 2358 (two outputs, one input) to function. If this is 2359 defined, the board configuration must define several 2360 SPI configuration items (port pins to use, etc). For 2361 an example, see include/configs/sacsng.h. 2362 2363 CONFIG_HARD_SPI 2364 2365 Enables a hardware SPI driver for general-purpose reads 2366 and writes. As with CONFIG_SOFT_SPI, the board configuration 2367 must define a list of chip-select function pointers. 2368 Currently supported on some MPC8xxx processors. For an 2369 example, see include/configs/mpc8349emds.h. 2370 2371 CONFIG_MXC_SPI 2372 2373 Enables the driver for the SPI controllers on i.MX and MXC 2374 SoCs. Currently i.MX31/35/51 are supported. 2375 2376 CONFIG_SYS_SPI_MXC_WAIT 2377 Timeout for waiting until spi transfer completed. 2378 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2379 2380- FPGA Support: CONFIG_FPGA 2381 2382 Enables FPGA subsystem. 2383 2384 CONFIG_FPGA_<vendor> 2385 2386 Enables support for specific chip vendors. 2387 (ALTERA, XILINX) 2388 2389 CONFIG_FPGA_<family> 2390 2391 Enables support for FPGA family. 2392 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2393 2394 CONFIG_FPGA_COUNT 2395 2396 Specify the number of FPGA devices to support. 2397 2398 CONFIG_CMD_FPGA_LOADMK 2399 2400 Enable support for fpga loadmk command 2401 2402 CONFIG_CMD_FPGA_LOADP 2403 2404 Enable support for fpga loadp command - load partial bitstream 2405 2406 CONFIG_CMD_FPGA_LOADBP 2407 2408 Enable support for fpga loadbp command - load partial bitstream 2409 (Xilinx only) 2410 2411 CONFIG_SYS_FPGA_PROG_FEEDBACK 2412 2413 Enable printing of hash marks during FPGA configuration. 2414 2415 CONFIG_SYS_FPGA_CHECK_BUSY 2416 2417 Enable checks on FPGA configuration interface busy 2418 status by the configuration function. This option 2419 will require a board or device specific function to 2420 be written. 2421 2422 CONFIG_FPGA_DELAY 2423 2424 If defined, a function that provides delays in the FPGA 2425 configuration driver. 2426 2427 CONFIG_SYS_FPGA_CHECK_CTRLC 2428 Allow Control-C to interrupt FPGA configuration 2429 2430 CONFIG_SYS_FPGA_CHECK_ERROR 2431 2432 Check for configuration errors during FPGA bitfile 2433 loading. For example, abort during Virtex II 2434 configuration if the INIT_B line goes low (which 2435 indicated a CRC error). 2436 2437 CONFIG_SYS_FPGA_WAIT_INIT 2438 2439 Maximum time to wait for the INIT_B line to de-assert 2440 after PROB_B has been de-asserted during a Virtex II 2441 FPGA configuration sequence. The default time is 500 2442 ms. 2443 2444 CONFIG_SYS_FPGA_WAIT_BUSY 2445 2446 Maximum time to wait for BUSY to de-assert during 2447 Virtex II FPGA configuration. The default is 5 ms. 2448 2449 CONFIG_SYS_FPGA_WAIT_CONFIG 2450 2451 Time to wait after FPGA configuration. The default is 2452 200 ms. 2453 2454- Configuration Management: 2455 CONFIG_BUILD_TARGET 2456 2457 Some SoCs need special image types (e.g. U-Boot binary 2458 with a special header) as build targets. By defining 2459 CONFIG_BUILD_TARGET in the SoC / board header, this 2460 special image will be automatically built upon calling 2461 make / buildman. 2462 2463 CONFIG_IDENT_STRING 2464 2465 If defined, this string will be added to the U-Boot 2466 version information (U_BOOT_VERSION) 2467 2468- Vendor Parameter Protection: 2469 2470 U-Boot considers the values of the environment 2471 variables "serial#" (Board Serial Number) and 2472 "ethaddr" (Ethernet Address) to be parameters that 2473 are set once by the board vendor / manufacturer, and 2474 protects these variables from casual modification by 2475 the user. Once set, these variables are read-only, 2476 and write or delete attempts are rejected. You can 2477 change this behaviour: 2478 2479 If CONFIG_ENV_OVERWRITE is #defined in your config 2480 file, the write protection for vendor parameters is 2481 completely disabled. Anybody can change or delete 2482 these parameters. 2483 2484 Alternatively, if you define _both_ an ethaddr in the 2485 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2486 Ethernet address is installed in the environment, 2487 which can be changed exactly ONCE by the user. [The 2488 serial# is unaffected by this, i. e. it remains 2489 read-only.] 2490 2491 The same can be accomplished in a more flexible way 2492 for any variable by configuring the type of access 2493 to allow for those variables in the ".flags" variable 2494 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2495 2496- Protected RAM: 2497 CONFIG_PRAM 2498 2499 Define this variable to enable the reservation of 2500 "protected RAM", i. e. RAM which is not overwritten 2501 by U-Boot. Define CONFIG_PRAM to hold the number of 2502 kB you want to reserve for pRAM. You can overwrite 2503 this default value by defining an environment 2504 variable "pram" to the number of kB you want to 2505 reserve. Note that the board info structure will 2506 still show the full amount of RAM. If pRAM is 2507 reserved, a new environment variable "mem" will 2508 automatically be defined to hold the amount of 2509 remaining RAM in a form that can be passed as boot 2510 argument to Linux, for instance like that: 2511 2512 setenv bootargs ... mem=\${mem} 2513 saveenv 2514 2515 This way you can tell Linux not to use this memory, 2516 either, which results in a memory region that will 2517 not be affected by reboots. 2518 2519 *WARNING* If your board configuration uses automatic 2520 detection of the RAM size, you must make sure that 2521 this memory test is non-destructive. So far, the 2522 following board configurations are known to be 2523 "pRAM-clean": 2524 2525 IVMS8, IVML24, SPD8xx, TQM8xxL, 2526 HERMES, IP860, RPXlite, LWMON, 2527 FLAGADM, TQM8260 2528 2529- Access to physical memory region (> 4GB) 2530 Some basic support is provided for operations on memory not 2531 normally accessible to U-Boot - e.g. some architectures 2532 support access to more than 4GB of memory on 32-bit 2533 machines using physical address extension or similar. 2534 Define CONFIG_PHYSMEM to access this basic support, which 2535 currently only supports clearing the memory. 2536 2537- Error Recovery: 2538 CONFIG_PANIC_HANG 2539 2540 Define this variable to stop the system in case of a 2541 fatal error, so that you have to reset it manually. 2542 This is probably NOT a good idea for an embedded 2543 system where you want the system to reboot 2544 automatically as fast as possible, but it may be 2545 useful during development since you can try to debug 2546 the conditions that lead to the situation. 2547 2548 CONFIG_NET_RETRY_COUNT 2549 2550 This variable defines the number of retries for 2551 network operations like ARP, RARP, TFTP, or BOOTP 2552 before giving up the operation. If not defined, a 2553 default value of 5 is used. 2554 2555 CONFIG_ARP_TIMEOUT 2556 2557 Timeout waiting for an ARP reply in milliseconds. 2558 2559 CONFIG_NFS_TIMEOUT 2560 2561 Timeout in milliseconds used in NFS protocol. 2562 If you encounter "ERROR: Cannot umount" in nfs command, 2563 try longer timeout such as 2564 #define CONFIG_NFS_TIMEOUT 10000UL 2565 2566- Command Interpreter: 2567 CONFIG_AUTO_COMPLETE 2568 2569 Enable auto completion of commands using TAB. 2570 2571 CONFIG_SYS_PROMPT_HUSH_PS2 2572 2573 This defines the secondary prompt string, which is 2574 printed when the command interpreter needs more input 2575 to complete a command. Usually "> ". 2576 2577 Note: 2578 2579 In the current implementation, the local variables 2580 space and global environment variables space are 2581 separated. Local variables are those you define by 2582 simply typing `name=value'. To access a local 2583 variable later on, you have write `$name' or 2584 `${name}'; to execute the contents of a variable 2585 directly type `$name' at the command prompt. 2586 2587 Global environment variables are those you use 2588 setenv/printenv to work with. To run a command stored 2589 in such a variable, you need to use the run command, 2590 and you must not use the '$' sign to access them. 2591 2592 To store commands and special characters in a 2593 variable, please use double quotation marks 2594 surrounding the whole text of the variable, instead 2595 of the backslashes before semicolons and special 2596 symbols. 2597 2598- Command Line Editing and History: 2599 CONFIG_CMDLINE_EDITING 2600 2601 Enable editing and History functions for interactive 2602 command line input operations 2603 2604- Command Line PS1/PS2 support: 2605 CONFIG_CMDLINE_PS_SUPPORT 2606 2607 Enable support for changing the command prompt string 2608 at run-time. Only static string is supported so far. 2609 The string is obtained from environment variables PS1 2610 and PS2. 2611 2612- Default Environment: 2613 CONFIG_EXTRA_ENV_SETTINGS 2614 2615 Define this to contain any number of null terminated 2616 strings (variable = value pairs) that will be part of 2617 the default environment compiled into the boot image. 2618 2619 For example, place something like this in your 2620 board's config file: 2621 2622 #define CONFIG_EXTRA_ENV_SETTINGS \ 2623 "myvar1=value1\0" \ 2624 "myvar2=value2\0" 2625 2626 Warning: This method is based on knowledge about the 2627 internal format how the environment is stored by the 2628 U-Boot code. This is NOT an official, exported 2629 interface! Although it is unlikely that this format 2630 will change soon, there is no guarantee either. 2631 You better know what you are doing here. 2632 2633 Note: overly (ab)use of the default environment is 2634 discouraged. Make sure to check other ways to preset 2635 the environment like the "source" command or the 2636 boot command first. 2637 2638 CONFIG_ENV_VARS_UBOOT_CONFIG 2639 2640 Define this in order to add variables describing the 2641 U-Boot build configuration to the default environment. 2642 These will be named arch, cpu, board, vendor, and soc. 2643 2644 Enabling this option will cause the following to be defined: 2645 2646 - CONFIG_SYS_ARCH 2647 - CONFIG_SYS_CPU 2648 - CONFIG_SYS_BOARD 2649 - CONFIG_SYS_VENDOR 2650 - CONFIG_SYS_SOC 2651 2652 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2653 2654 Define this in order to add variables describing certain 2655 run-time determined information about the hardware to the 2656 environment. These will be named board_name, board_rev. 2657 2658 CONFIG_DELAY_ENVIRONMENT 2659 2660 Normally the environment is loaded when the board is 2661 initialised so that it is available to U-Boot. This inhibits 2662 that so that the environment is not available until 2663 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2664 this is instead controlled by the value of 2665 /config/load-environment. 2666 2667- DataFlash Support: 2668 CONFIG_HAS_DATAFLASH 2669 2670 Defining this option enables DataFlash features and 2671 allows to read/write in Dataflash via the standard 2672 commands cp, md... 2673 2674- Serial Flash support 2675 CONFIG_CMD_SF 2676 2677 Defining this option enables SPI flash commands 2678 'sf probe/read/write/erase/update'. 2679 2680 Usage requires an initial 'probe' to define the serial 2681 flash parameters, followed by read/write/erase/update 2682 commands. 2683 2684 The following defaults may be provided by the platform 2685 to handle the common case when only a single serial 2686 flash is present on the system. 2687 2688 CONFIG_SF_DEFAULT_BUS Bus identifier 2689 CONFIG_SF_DEFAULT_CS Chip-select 2690 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2691 CONFIG_SF_DEFAULT_SPEED in Hz 2692 2693 CONFIG_CMD_SF_TEST 2694 2695 Define this option to include a destructive SPI flash 2696 test ('sf test'). 2697 2698 CONFIG_SF_DUAL_FLASH Dual flash memories 2699 2700 Define this option to use dual flash support where two flash 2701 memories can be connected with a given cs line. 2702 Currently Xilinx Zynq qspi supports these type of connections. 2703 2704- SystemACE Support: 2705 CONFIG_SYSTEMACE 2706 2707 Adding this option adds support for Xilinx SystemACE 2708 chips attached via some sort of local bus. The address 2709 of the chip must also be defined in the 2710 CONFIG_SYS_SYSTEMACE_BASE macro. For example: 2711 2712 #define CONFIG_SYSTEMACE 2713 #define CONFIG_SYS_SYSTEMACE_BASE 0xf0000000 2714 2715 When SystemACE support is added, the "ace" device type 2716 becomes available to the fat commands, i.e. fatls. 2717 2718- TFTP Fixed UDP Port: 2719 CONFIG_TFTP_PORT 2720 2721 If this is defined, the environment variable tftpsrcp 2722 is used to supply the TFTP UDP source port value. 2723 If tftpsrcp isn't defined, the normal pseudo-random port 2724 number generator is used. 2725 2726 Also, the environment variable tftpdstp is used to supply 2727 the TFTP UDP destination port value. If tftpdstp isn't 2728 defined, the normal port 69 is used. 2729 2730 The purpose for tftpsrcp is to allow a TFTP server to 2731 blindly start the TFTP transfer using the pre-configured 2732 target IP address and UDP port. This has the effect of 2733 "punching through" the (Windows XP) firewall, allowing 2734 the remainder of the TFTP transfer to proceed normally. 2735 A better solution is to properly configure the firewall, 2736 but sometimes that is not allowed. 2737 2738- Hashing support: 2739 CONFIG_CMD_HASH 2740 2741 This enables a generic 'hash' command which can produce 2742 hashes / digests from a few algorithms (e.g. SHA1, SHA256). 2743 2744 CONFIG_HASH_VERIFY 2745 2746 Enable the hash verify command (hash -v). This adds to code 2747 size a little. 2748 2749 Note: There is also a sha1sum command, which should perhaps 2750 be deprecated in favour of 'hash sha1'. 2751 2752- Freescale i.MX specific commands: 2753 CONFIG_CMD_HDMIDETECT 2754 This enables 'hdmidet' command which returns true if an 2755 HDMI monitor is detected. This command is i.MX 6 specific. 2756 2757- bootcount support: 2758 CONFIG_BOOTCOUNT_LIMIT 2759 2760 This enables the bootcounter support, see: 2761 http://www.denx.de/wiki/DULG/UBootBootCountLimit 2762 2763 CONFIG_AT91SAM9XE 2764 enable special bootcounter support on at91sam9xe based boards. 2765 CONFIG_SOC_DA8XX 2766 enable special bootcounter support on da850 based boards. 2767 CONFIG_BOOTCOUNT_RAM 2768 enable support for the bootcounter in RAM 2769 CONFIG_BOOTCOUNT_I2C 2770 enable support for the bootcounter on an i2c (like RTC) device. 2771 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2772 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2773 the bootcounter. 2774 CONFIG_BOOTCOUNT_ALEN = address len 2775 2776- Show boot progress: 2777 CONFIG_SHOW_BOOT_PROGRESS 2778 2779 Defining this option allows to add some board- 2780 specific code (calling a user-provided function 2781 "show_boot_progress(int)") that enables you to show 2782 the system's boot progress on some display (for 2783 example, some LED's) on your board. At the moment, 2784 the following checkpoints are implemented: 2785 2786 2787Legacy uImage format: 2788 2789 Arg Where When 2790 1 common/cmd_bootm.c before attempting to boot an image 2791 -1 common/cmd_bootm.c Image header has bad magic number 2792 2 common/cmd_bootm.c Image header has correct magic number 2793 -2 common/cmd_bootm.c Image header has bad checksum 2794 3 common/cmd_bootm.c Image header has correct checksum 2795 -3 common/cmd_bootm.c Image data has bad checksum 2796 4 common/cmd_bootm.c Image data has correct checksum 2797 -4 common/cmd_bootm.c Image is for unsupported architecture 2798 5 common/cmd_bootm.c Architecture check OK 2799 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2800 6 common/cmd_bootm.c Image Type check OK 2801 -6 common/cmd_bootm.c gunzip uncompression error 2802 -7 common/cmd_bootm.c Unimplemented compression type 2803 7 common/cmd_bootm.c Uncompression OK 2804 8 common/cmd_bootm.c No uncompress/copy overwrite error 2805 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2806 2807 9 common/image.c Start initial ramdisk verification 2808 -10 common/image.c Ramdisk header has bad magic number 2809 -11 common/image.c Ramdisk header has bad checksum 2810 10 common/image.c Ramdisk header is OK 2811 -12 common/image.c Ramdisk data has bad checksum 2812 11 common/image.c Ramdisk data has correct checksum 2813 12 common/image.c Ramdisk verification complete, start loading 2814 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2815 13 common/image.c Start multifile image verification 2816 14 common/image.c No initial ramdisk, no multifile, continue. 2817 2818 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2819 2820 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2821 -31 post/post.c POST test failed, detected by post_output_backlog() 2822 -32 post/post.c POST test failed, detected by post_run_single() 2823 2824 34 common/cmd_doc.c before loading a Image from a DOC device 2825 -35 common/cmd_doc.c Bad usage of "doc" command 2826 35 common/cmd_doc.c correct usage of "doc" command 2827 -36 common/cmd_doc.c No boot device 2828 36 common/cmd_doc.c correct boot device 2829 -37 common/cmd_doc.c Unknown Chip ID on boot device 2830 37 common/cmd_doc.c correct chip ID found, device available 2831 -38 common/cmd_doc.c Read Error on boot device 2832 38 common/cmd_doc.c reading Image header from DOC device OK 2833 -39 common/cmd_doc.c Image header has bad magic number 2834 39 common/cmd_doc.c Image header has correct magic number 2835 -40 common/cmd_doc.c Error reading Image from DOC device 2836 40 common/cmd_doc.c Image header has correct magic number 2837 41 common/cmd_ide.c before loading a Image from a IDE device 2838 -42 common/cmd_ide.c Bad usage of "ide" command 2839 42 common/cmd_ide.c correct usage of "ide" command 2840 -43 common/cmd_ide.c No boot device 2841 43 common/cmd_ide.c boot device found 2842 -44 common/cmd_ide.c Device not available 2843 44 common/cmd_ide.c Device available 2844 -45 common/cmd_ide.c wrong partition selected 2845 45 common/cmd_ide.c partition selected 2846 -46 common/cmd_ide.c Unknown partition table 2847 46 common/cmd_ide.c valid partition table found 2848 -47 common/cmd_ide.c Invalid partition type 2849 47 common/cmd_ide.c correct partition type 2850 -48 common/cmd_ide.c Error reading Image Header on boot device 2851 48 common/cmd_ide.c reading Image Header from IDE device OK 2852 -49 common/cmd_ide.c Image header has bad magic number 2853 49 common/cmd_ide.c Image header has correct magic number 2854 -50 common/cmd_ide.c Image header has bad checksum 2855 50 common/cmd_ide.c Image header has correct checksum 2856 -51 common/cmd_ide.c Error reading Image from IDE device 2857 51 common/cmd_ide.c reading Image from IDE device OK 2858 52 common/cmd_nand.c before loading a Image from a NAND device 2859 -53 common/cmd_nand.c Bad usage of "nand" command 2860 53 common/cmd_nand.c correct usage of "nand" command 2861 -54 common/cmd_nand.c No boot device 2862 54 common/cmd_nand.c boot device found 2863 -55 common/cmd_nand.c Unknown Chip ID on boot device 2864 55 common/cmd_nand.c correct chip ID found, device available 2865 -56 common/cmd_nand.c Error reading Image Header on boot device 2866 56 common/cmd_nand.c reading Image Header from NAND device OK 2867 -57 common/cmd_nand.c Image header has bad magic number 2868 57 common/cmd_nand.c Image header has correct magic number 2869 -58 common/cmd_nand.c Error reading Image from NAND device 2870 58 common/cmd_nand.c reading Image from NAND device OK 2871 2872 -60 common/env_common.c Environment has a bad CRC, using default 2873 2874 64 net/eth.c starting with Ethernet configuration. 2875 -64 net/eth.c no Ethernet found. 2876 65 net/eth.c Ethernet found. 2877 2878 -80 common/cmd_net.c usage wrong 2879 80 common/cmd_net.c before calling net_loop() 2880 -81 common/cmd_net.c some error in net_loop() occurred 2881 81 common/cmd_net.c net_loop() back without error 2882 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2883 82 common/cmd_net.c trying automatic boot 2884 83 common/cmd_net.c running "source" command 2885 -83 common/cmd_net.c some error in automatic boot or "source" command 2886 84 common/cmd_net.c end without errors 2887 2888FIT uImage format: 2889 2890 Arg Where When 2891 100 common/cmd_bootm.c Kernel FIT Image has correct format 2892 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2893 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2894 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2895 102 common/cmd_bootm.c Kernel unit name specified 2896 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2897 103 common/cmd_bootm.c Found configuration node 2898 104 common/cmd_bootm.c Got kernel subimage node offset 2899 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2900 105 common/cmd_bootm.c Kernel subimage hash verification OK 2901 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2902 106 common/cmd_bootm.c Architecture check OK 2903 -106 common/cmd_bootm.c Kernel subimage has wrong type 2904 107 common/cmd_bootm.c Kernel subimage type OK 2905 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2906 108 common/cmd_bootm.c Got kernel subimage data/size 2907 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2908 -109 common/cmd_bootm.c Can't get kernel subimage type 2909 -110 common/cmd_bootm.c Can't get kernel subimage comp 2910 -111 common/cmd_bootm.c Can't get kernel subimage os 2911 -112 common/cmd_bootm.c Can't get kernel subimage load address 2912 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2913 2914 120 common/image.c Start initial ramdisk verification 2915 -120 common/image.c Ramdisk FIT image has incorrect format 2916 121 common/image.c Ramdisk FIT image has correct format 2917 122 common/image.c No ramdisk subimage unit name, using configuration 2918 -122 common/image.c Can't get configuration for ramdisk subimage 2919 123 common/image.c Ramdisk unit name specified 2920 -124 common/image.c Can't get ramdisk subimage node offset 2921 125 common/image.c Got ramdisk subimage node offset 2922 -125 common/image.c Ramdisk subimage hash verification failed 2923 126 common/image.c Ramdisk subimage hash verification OK 2924 -126 common/image.c Ramdisk subimage for unsupported architecture 2925 127 common/image.c Architecture check OK 2926 -127 common/image.c Can't get ramdisk subimage data/size 2927 128 common/image.c Got ramdisk subimage data/size 2928 129 common/image.c Can't get ramdisk load address 2929 -129 common/image.c Got ramdisk load address 2930 2931 -130 common/cmd_doc.c Incorrect FIT image format 2932 131 common/cmd_doc.c FIT image format OK 2933 2934 -140 common/cmd_ide.c Incorrect FIT image format 2935 141 common/cmd_ide.c FIT image format OK 2936 2937 -150 common/cmd_nand.c Incorrect FIT image format 2938 151 common/cmd_nand.c FIT image format OK 2939 2940- legacy image format: 2941 CONFIG_IMAGE_FORMAT_LEGACY 2942 enables the legacy image format support in U-Boot. 2943 2944 Default: 2945 enabled if CONFIG_FIT_SIGNATURE is not defined. 2946 2947 CONFIG_DISABLE_IMAGE_LEGACY 2948 disable the legacy image format 2949 2950 This define is introduced, as the legacy image format is 2951 enabled per default for backward compatibility. 2952 2953- Standalone program support: 2954 CONFIG_STANDALONE_LOAD_ADDR 2955 2956 This option defines a board specific value for the 2957 address where standalone program gets loaded, thus 2958 overwriting the architecture dependent default 2959 settings. 2960 2961- Frame Buffer Address: 2962 CONFIG_FB_ADDR 2963 2964 Define CONFIG_FB_ADDR if you want to use specific 2965 address for frame buffer. This is typically the case 2966 when using a graphics controller has separate video 2967 memory. U-Boot will then place the frame buffer at 2968 the given address instead of dynamically reserving it 2969 in system RAM by calling lcd_setmem(), which grabs 2970 the memory for the frame buffer depending on the 2971 configured panel size. 2972 2973 Please see board_init_f function. 2974 2975- Automatic software updates via TFTP server 2976 CONFIG_UPDATE_TFTP 2977 CONFIG_UPDATE_TFTP_CNT_MAX 2978 CONFIG_UPDATE_TFTP_MSEC_MAX 2979 2980 These options enable and control the auto-update feature; 2981 for a more detailed description refer to doc/README.update. 2982 2983- MTD Support (mtdparts command, UBI support) 2984 CONFIG_MTD_DEVICE 2985 2986 Adds the MTD device infrastructure from the Linux kernel. 2987 Needed for mtdparts command support. 2988 2989 CONFIG_MTD_PARTITIONS 2990 2991 Adds the MTD partitioning infrastructure from the Linux 2992 kernel. Needed for UBI support. 2993 2994- UBI support 2995 CONFIG_CMD_UBI 2996 2997 Adds commands for interacting with MTD partitions formatted 2998 with the UBI flash translation layer 2999 3000 Requires also defining CONFIG_RBTREE 3001 3002 CONFIG_UBI_SILENCE_MSG 3003 3004 Make the verbose messages from UBI stop printing. This leaves 3005 warnings and errors enabled. 3006 3007 3008 CONFIG_MTD_UBI_WL_THRESHOLD 3009 This parameter defines the maximum difference between the highest 3010 erase counter value and the lowest erase counter value of eraseblocks 3011 of UBI devices. When this threshold is exceeded, UBI starts performing 3012 wear leveling by means of moving data from eraseblock with low erase 3013 counter to eraseblocks with high erase counter. 3014 3015 The default value should be OK for SLC NAND flashes, NOR flashes and 3016 other flashes which have eraseblock life-cycle 100000 or more. 3017 However, in case of MLC NAND flashes which typically have eraseblock 3018 life-cycle less than 10000, the threshold should be lessened (e.g., 3019 to 128 or 256, although it does not have to be power of 2). 3020 3021 default: 4096 3022 3023 CONFIG_MTD_UBI_BEB_LIMIT 3024 This option specifies the maximum bad physical eraseblocks UBI 3025 expects on the MTD device (per 1024 eraseblocks). If the 3026 underlying flash does not admit of bad eraseblocks (e.g. NOR 3027 flash), this value is ignored. 3028 3029 NAND datasheets often specify the minimum and maximum NVM 3030 (Number of Valid Blocks) for the flashes' endurance lifetime. 3031 The maximum expected bad eraseblocks per 1024 eraseblocks 3032 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 3033 which gives 20 for most NANDs (MaxNVB is basically the total 3034 count of eraseblocks on the chip). 3035 3036 To put it differently, if this value is 20, UBI will try to 3037 reserve about 1.9% of physical eraseblocks for bad blocks 3038 handling. And that will be 1.9% of eraseblocks on the entire 3039 NAND chip, not just the MTD partition UBI attaches. This means 3040 that if you have, say, a NAND flash chip admits maximum 40 bad 3041 eraseblocks, and it is split on two MTD partitions of the same 3042 size, UBI will reserve 40 eraseblocks when attaching a 3043 partition. 3044 3045 default: 20 3046 3047 CONFIG_MTD_UBI_FASTMAP 3048 Fastmap is a mechanism which allows attaching an UBI device 3049 in nearly constant time. Instead of scanning the whole MTD device it 3050 only has to locate a checkpoint (called fastmap) on the device. 3051 The on-flash fastmap contains all information needed to attach 3052 the device. Using fastmap makes only sense on large devices where 3053 attaching by scanning takes long. UBI will not automatically install 3054 a fastmap on old images, but you can set the UBI parameter 3055 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 3056 that fastmap-enabled images are still usable with UBI implementations 3057 without fastmap support. On typical flash devices the whole fastmap 3058 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 3059 3060 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 3061 Set this parameter to enable fastmap automatically on images 3062 without a fastmap. 3063 default: 0 3064 3065 CONFIG_MTD_UBI_FM_DEBUG 3066 Enable UBI fastmap debug 3067 default: 0 3068 3069- UBIFS support 3070 CONFIG_CMD_UBIFS 3071 3072 Adds commands for interacting with UBI volumes formatted as 3073 UBIFS. UBIFS is read-only in u-boot. 3074 3075 Requires UBI support as well as CONFIG_LZO 3076 3077 CONFIG_UBIFS_SILENCE_MSG 3078 3079 Make the verbose messages from UBIFS stop printing. This leaves 3080 warnings and errors enabled. 3081 3082- SPL framework 3083 CONFIG_SPL 3084 Enable building of SPL globally. 3085 3086 CONFIG_SPL_LDSCRIPT 3087 LDSCRIPT for linking the SPL binary. 3088 3089 CONFIG_SPL_MAX_FOOTPRINT 3090 Maximum size in memory allocated to the SPL, BSS included. 3091 When defined, the linker checks that the actual memory 3092 used by SPL from _start to __bss_end does not exceed it. 3093 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3094 must not be both defined at the same time. 3095 3096 CONFIG_SPL_MAX_SIZE 3097 Maximum size of the SPL image (text, data, rodata, and 3098 linker lists sections), BSS excluded. 3099 When defined, the linker checks that the actual size does 3100 not exceed it. 3101 3102 CONFIG_SPL_TEXT_BASE 3103 TEXT_BASE for linking the SPL binary. 3104 3105 CONFIG_SPL_RELOC_TEXT_BASE 3106 Address to relocate to. If unspecified, this is equal to 3107 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 3108 3109 CONFIG_SPL_BSS_START_ADDR 3110 Link address for the BSS within the SPL binary. 3111 3112 CONFIG_SPL_BSS_MAX_SIZE 3113 Maximum size in memory allocated to the SPL BSS. 3114 When defined, the linker checks that the actual memory used 3115 by SPL from __bss_start to __bss_end does not exceed it. 3116 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 3117 must not be both defined at the same time. 3118 3119 CONFIG_SPL_STACK 3120 Adress of the start of the stack SPL will use 3121 3122 CONFIG_SPL_PANIC_ON_RAW_IMAGE 3123 When defined, SPL will panic() if the image it has 3124 loaded does not have a signature. 3125 Defining this is useful when code which loads images 3126 in SPL cannot guarantee that absolutely all read errors 3127 will be caught. 3128 An example is the LPC32XX MLC NAND driver, which will 3129 consider that a completely unreadable NAND block is bad, 3130 and thus should be skipped silently. 3131 3132 CONFIG_SPL_RELOC_STACK 3133 Adress of the start of the stack SPL will use after 3134 relocation. If unspecified, this is equal to 3135 CONFIG_SPL_STACK. 3136 3137 CONFIG_SYS_SPL_MALLOC_START 3138 Starting address of the malloc pool used in SPL. 3139 When this option is set the full malloc is used in SPL and 3140 it is set up by spl_init() and before that, the simple malloc() 3141 can be used if CONFIG_SYS_MALLOC_F is defined. 3142 3143 CONFIG_SYS_SPL_MALLOC_SIZE 3144 The size of the malloc pool used in SPL. 3145 3146 CONFIG_SPL_FRAMEWORK 3147 Enable the SPL framework under common/. This framework 3148 supports MMC, NAND and YMODEM loading of U-Boot and NAND 3149 NAND loading of the Linux Kernel. 3150 3151 CONFIG_SPL_OS_BOOT 3152 Enable booting directly to an OS from SPL. 3153 See also: doc/README.falcon 3154 3155 CONFIG_SPL_DISPLAY_PRINT 3156 For ARM, enable an optional function to print more information 3157 about the running system. 3158 3159 CONFIG_SPL_INIT_MINIMAL 3160 Arch init code should be built for a very small image 3161 3162 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 3163 Partition on the MMC to load U-Boot from when the MMC is being 3164 used in raw mode 3165 3166 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 3167 Sector to load kernel uImage from when MMC is being 3168 used in raw mode (for Falcon mode) 3169 3170 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 3171 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 3172 Sector and number of sectors to load kernel argument 3173 parameters from when MMC is being used in raw mode 3174 (for falcon mode) 3175 3176 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 3177 Partition on the MMC to load U-Boot from when the MMC is being 3178 used in fs mode 3179 3180 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 3181 Filename to read to load U-Boot when reading from filesystem 3182 3183 CONFIG_SPL_FS_LOAD_KERNEL_NAME 3184 Filename to read to load kernel uImage when reading 3185 from filesystem (for Falcon mode) 3186 3187 CONFIG_SPL_FS_LOAD_ARGS_NAME 3188 Filename to read to load kernel argument parameters 3189 when reading from filesystem (for Falcon mode) 3190 3191 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 3192 Set this for NAND SPL on PPC mpc83xx targets, so that 3193 start.S waits for the rest of the SPL to load before 3194 continuing (the hardware starts execution after just 3195 loading the first page rather than the full 4K). 3196 3197 CONFIG_SPL_SKIP_RELOCATE 3198 Avoid SPL relocation 3199 3200 CONFIG_SPL_NAND_BASE 3201 Include nand_base.c in the SPL. Requires 3202 CONFIG_SPL_NAND_DRIVERS. 3203 3204 CONFIG_SPL_NAND_DRIVERS 3205 SPL uses normal NAND drivers, not minimal drivers. 3206 3207 CONFIG_SPL_NAND_ECC 3208 Include standard software ECC in the SPL 3209 3210 CONFIG_SPL_NAND_SIMPLE 3211 Support for NAND boot using simple NAND drivers that 3212 expose the cmd_ctrl() interface. 3213 3214 CONFIG_SPL_UBI 3215 Support for a lightweight UBI (fastmap) scanner and 3216 loader 3217 3218 CONFIG_SPL_NAND_RAW_ONLY 3219 Support to boot only raw u-boot.bin images. Use this only 3220 if you need to save space. 3221 3222 CONFIG_SPL_COMMON_INIT_DDR 3223 Set for common ddr init with serial presence detect in 3224 SPL binary. 3225 3226 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 3227 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 3228 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 3229 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 3230 CONFIG_SYS_NAND_ECCBYTES 3231 Defines the size and behavior of the NAND that SPL uses 3232 to read U-Boot 3233 3234 CONFIG_SPL_NAND_BOOT 3235 Add support NAND boot 3236 3237 CONFIG_SYS_NAND_U_BOOT_OFFS 3238 Location in NAND to read U-Boot from 3239 3240 CONFIG_SYS_NAND_U_BOOT_DST 3241 Location in memory to load U-Boot to 3242 3243 CONFIG_SYS_NAND_U_BOOT_SIZE 3244 Size of image to load 3245 3246 CONFIG_SYS_NAND_U_BOOT_START 3247 Entry point in loaded image to jump to 3248 3249 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 3250 Define this if you need to first read the OOB and then the 3251 data. This is used, for example, on davinci platforms. 3252 3253 CONFIG_SPL_OMAP3_ID_NAND 3254 Support for an OMAP3-specific set of functions to return the 3255 ID and MFR of the first attached NAND chip, if present. 3256 3257 CONFIG_SPL_RAM_DEVICE 3258 Support for running image already present in ram, in SPL binary 3259 3260 CONFIG_SPL_PAD_TO 3261 Image offset to which the SPL should be padded before appending 3262 the SPL payload. By default, this is defined as 3263 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3264 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3265 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3266 3267 CONFIG_SPL_TARGET 3268 Final target image containing SPL and payload. Some SPLs 3269 use an arch-specific makefile fragment instead, for 3270 example if more than one image needs to be produced. 3271 3272 CONFIG_FIT_SPL_PRINT 3273 Printing information about a FIT image adds quite a bit of 3274 code to SPL. So this is normally disabled in SPL. Use this 3275 option to re-enable it. This will affect the output of the 3276 bootm command when booting a FIT image. 3277 3278- TPL framework 3279 CONFIG_TPL 3280 Enable building of TPL globally. 3281 3282 CONFIG_TPL_PAD_TO 3283 Image offset to which the TPL should be padded before appending 3284 the TPL payload. By default, this is defined as 3285 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 3286 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 3287 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 3288 3289- Interrupt support (PPC): 3290 3291 There are common interrupt_init() and timer_interrupt() 3292 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 3293 for CPU specific initialization. interrupt_init_cpu() 3294 should set decrementer_count to appropriate value. If 3295 CPU resets decrementer automatically after interrupt 3296 (ppc4xx) it should set decrementer_count to zero. 3297 timer_interrupt() calls timer_interrupt_cpu() for CPU 3298 specific handling. If board has watchdog / status_led 3299 / other_activity_monitor it works automatically from 3300 general timer_interrupt(). 3301 3302 3303Board initialization settings: 3304------------------------------ 3305 3306During Initialization u-boot calls a number of board specific functions 3307to allow the preparation of board specific prerequisites, e.g. pin setup 3308before drivers are initialized. To enable these callbacks the 3309following configuration macros have to be defined. Currently this is 3310architecture specific, so please check arch/your_architecture/lib/board.c 3311typically in board_init_f() and board_init_r(). 3312 3313- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 3314- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 3315- CONFIG_BOARD_LATE_INIT: Call board_late_init() 3316- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 3317 3318Configuration Settings: 3319----------------------- 3320 3321- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 3322 Optionally it can be defined to support 64-bit memory commands. 3323 3324- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 3325 undefine this when you're short of memory. 3326 3327- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 3328 width of the commands listed in the 'help' command output. 3329 3330- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 3331 prompt for user input. 3332 3333- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 3334 3335- CONFIG_SYS_PBSIZE: Buffer size for Console output 3336 3337- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 3338 3339- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 3340 the application (usually a Linux kernel) when it is 3341 booted 3342 3343- CONFIG_SYS_BAUDRATE_TABLE: 3344 List of legal baudrate settings for this board. 3345 3346- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 3347 Begin and End addresses of the area used by the 3348 simple memory test. 3349 3350- CONFIG_SYS_ALT_MEMTEST: 3351 Enable an alternate, more extensive memory test. 3352 3353- CONFIG_SYS_MEMTEST_SCRATCH: 3354 Scratch address used by the alternate memory test 3355 You only need to set this if address zero isn't writeable 3356 3357- CONFIG_SYS_MEM_RESERVE_SECURE 3358 Only implemented for ARMv8 for now. 3359 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 3360 is substracted from total RAM and won't be reported to OS. 3361 This memory can be used as secure memory. A variable 3362 gd->arch.secure_ram is used to track the location. In systems 3363 the RAM base is not zero, or RAM is divided into banks, 3364 this variable needs to be recalcuated to get the address. 3365 3366- CONFIG_SYS_MEM_TOP_HIDE: 3367 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 3368 this specified memory area will get subtracted from the top 3369 (end) of RAM and won't get "touched" at all by U-Boot. By 3370 fixing up gd->ram_size the Linux kernel should gets passed 3371 the now "corrected" memory size and won't touch it either. 3372 This should work for arch/ppc and arch/powerpc. Only Linux 3373 board ports in arch/powerpc with bootwrapper support that 3374 recalculate the memory size from the SDRAM controller setup 3375 will have to get fixed in Linux additionally. 3376 3377 This option can be used as a workaround for the 440EPx/GRx 3378 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 3379 be touched. 3380 3381 WARNING: Please make sure that this value is a multiple of 3382 the Linux page size (normally 4k). If this is not the case, 3383 then the end address of the Linux memory will be located at a 3384 non page size aligned address and this could cause major 3385 problems. 3386 3387- CONFIG_SYS_LOADS_BAUD_CHANGE: 3388 Enable temporary baudrate change while serial download 3389 3390- CONFIG_SYS_SDRAM_BASE: 3391 Physical start address of SDRAM. _Must_ be 0 here. 3392 3393- CONFIG_SYS_FLASH_BASE: 3394 Physical start address of Flash memory. 3395 3396- CONFIG_SYS_MONITOR_BASE: 3397 Physical start address of boot monitor code (set by 3398 make config files to be same as the text base address 3399 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 3400 CONFIG_SYS_FLASH_BASE when booting from flash. 3401 3402- CONFIG_SYS_MONITOR_LEN: 3403 Size of memory reserved for monitor code, used to 3404 determine _at_compile_time_ (!) if the environment is 3405 embedded within the U-Boot image, or in a separate 3406 flash sector. 3407 3408- CONFIG_SYS_MALLOC_LEN: 3409 Size of DRAM reserved for malloc() use. 3410 3411- CONFIG_SYS_MALLOC_F_LEN 3412 Size of the malloc() pool for use before relocation. If 3413 this is defined, then a very simple malloc() implementation 3414 will become available before relocation. The address is just 3415 below the global data, and the stack is moved down to make 3416 space. 3417 3418 This feature allocates regions with increasing addresses 3419 within the region. calloc() is supported, but realloc() 3420 is not available. free() is supported but does nothing. 3421 The memory will be freed (or in fact just forgotten) when 3422 U-Boot relocates itself. 3423 3424- CONFIG_SYS_MALLOC_SIMPLE 3425 Provides a simple and small malloc() and calloc() for those 3426 boards which do not use the full malloc in SPL (which is 3427 enabled with CONFIG_SYS_SPL_MALLOC_START). 3428 3429- CONFIG_SYS_NONCACHED_MEMORY: 3430 Size of non-cached memory area. This area of memory will be 3431 typically located right below the malloc() area and mapped 3432 uncached in the MMU. This is useful for drivers that would 3433 otherwise require a lot of explicit cache maintenance. For 3434 some drivers it's also impossible to properly maintain the 3435 cache. For example if the regions that need to be flushed 3436 are not a multiple of the cache-line size, *and* padding 3437 cannot be allocated between the regions to align them (i.e. 3438 if the HW requires a contiguous array of regions, and the 3439 size of each region is not cache-aligned), then a flush of 3440 one region may result in overwriting data that hardware has 3441 written to another region in the same cache-line. This can 3442 happen for example in network drivers where descriptors for 3443 buffers are typically smaller than the CPU cache-line (e.g. 3444 16 bytes vs. 32 or 64 bytes). 3445 3446 Non-cached memory is only supported on 32-bit ARM at present. 3447 3448- CONFIG_SYS_BOOTM_LEN: 3449 Normally compressed uImages are limited to an 3450 uncompressed size of 8 MBytes. If this is not enough, 3451 you can define CONFIG_SYS_BOOTM_LEN in your board config file 3452 to adjust this setting to your needs. 3453 3454- CONFIG_SYS_BOOTMAPSZ: 3455 Maximum size of memory mapped by the startup code of 3456 the Linux kernel; all data that must be processed by 3457 the Linux kernel (bd_info, boot arguments, FDT blob if 3458 used) must be put below this limit, unless "bootm_low" 3459 environment variable is defined and non-zero. In such case 3460 all data for the Linux kernel must be between "bootm_low" 3461 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3462 variable "bootm_mapsize" will override the value of 3463 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3464 then the value in "bootm_size" will be used instead. 3465 3466- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3467 Enable initrd_high functionality. If defined then the 3468 initrd_high feature is enabled and the bootm ramdisk subcommand 3469 is enabled. 3470 3471- CONFIG_SYS_BOOT_GET_CMDLINE: 3472 Enables allocating and saving kernel cmdline in space between 3473 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3474 3475- CONFIG_SYS_BOOT_GET_KBD: 3476 Enables allocating and saving a kernel copy of the bd_info in 3477 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3478 3479- CONFIG_SYS_MAX_FLASH_BANKS: 3480 Max number of Flash memory banks 3481 3482- CONFIG_SYS_MAX_FLASH_SECT: 3483 Max number of sectors on a Flash chip 3484 3485- CONFIG_SYS_FLASH_ERASE_TOUT: 3486 Timeout for Flash erase operations (in ms) 3487 3488- CONFIG_SYS_FLASH_WRITE_TOUT: 3489 Timeout for Flash write operations (in ms) 3490 3491- CONFIG_SYS_FLASH_LOCK_TOUT 3492 Timeout for Flash set sector lock bit operation (in ms) 3493 3494- CONFIG_SYS_FLASH_UNLOCK_TOUT 3495 Timeout for Flash clear lock bits operation (in ms) 3496 3497- CONFIG_SYS_FLASH_PROTECTION 3498 If defined, hardware flash sectors protection is used 3499 instead of U-Boot software protection. 3500 3501- CONFIG_SYS_DIRECT_FLASH_TFTP: 3502 3503 Enable TFTP transfers directly to flash memory; 3504 without this option such a download has to be 3505 performed in two steps: (1) download to RAM, and (2) 3506 copy from RAM to flash. 3507 3508 The two-step approach is usually more reliable, since 3509 you can check if the download worked before you erase 3510 the flash, but in some situations (when system RAM is 3511 too limited to allow for a temporary copy of the 3512 downloaded image) this option may be very useful. 3513 3514- CONFIG_SYS_FLASH_CFI: 3515 Define if the flash driver uses extra elements in the 3516 common flash structure for storing flash geometry. 3517 3518- CONFIG_FLASH_CFI_DRIVER 3519 This option also enables the building of the cfi_flash driver 3520 in the drivers directory 3521 3522- CONFIG_FLASH_CFI_MTD 3523 This option enables the building of the cfi_mtd driver 3524 in the drivers directory. The driver exports CFI flash 3525 to the MTD layer. 3526 3527- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3528 Use buffered writes to flash. 3529 3530- CONFIG_FLASH_SPANSION_S29WS_N 3531 s29ws-n MirrorBit flash has non-standard addresses for buffered 3532 write commands. 3533 3534- CONFIG_SYS_FLASH_QUIET_TEST 3535 If this option is defined, the common CFI flash doesn't 3536 print it's warning upon not recognized FLASH banks. This 3537 is useful, if some of the configured banks are only 3538 optionally available. 3539 3540- CONFIG_FLASH_SHOW_PROGRESS 3541 If defined (must be an integer), print out countdown 3542 digits and dots. Recommended value: 45 (9..1) for 80 3543 column displays, 15 (3..1) for 40 column displays. 3544 3545- CONFIG_FLASH_VERIFY 3546 If defined, the content of the flash (destination) is compared 3547 against the source after the write operation. An error message 3548 will be printed when the contents are not identical. 3549 Please note that this option is useless in nearly all cases, 3550 since such flash programming errors usually are detected earlier 3551 while unprotecting/erasing/programming. Please only enable 3552 this option if you really know what you are doing. 3553 3554- CONFIG_SYS_RX_ETH_BUFFER: 3555 Defines the number of Ethernet receive buffers. On some 3556 Ethernet controllers it is recommended to set this value 3557 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3558 buffers can be full shortly after enabling the interface 3559 on high Ethernet traffic. 3560 Defaults to 4 if not defined. 3561 3562- CONFIG_ENV_MAX_ENTRIES 3563 3564 Maximum number of entries in the hash table that is used 3565 internally to store the environment settings. The default 3566 setting is supposed to be generous and should work in most 3567 cases. This setting can be used to tune behaviour; see 3568 lib/hashtable.c for details. 3569 3570- CONFIG_ENV_FLAGS_LIST_DEFAULT 3571- CONFIG_ENV_FLAGS_LIST_STATIC 3572 Enable validation of the values given to environment variables when 3573 calling env set. Variables can be restricted to only decimal, 3574 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3575 the variables can also be restricted to IP address or MAC address. 3576 3577 The format of the list is: 3578 type_attribute = [s|d|x|b|i|m] 3579 access_attribute = [a|r|o|c] 3580 attributes = type_attribute[access_attribute] 3581 entry = variable_name[:attributes] 3582 list = entry[,list] 3583 3584 The type attributes are: 3585 s - String (default) 3586 d - Decimal 3587 x - Hexadecimal 3588 b - Boolean ([1yYtT|0nNfF]) 3589 i - IP address 3590 m - MAC address 3591 3592 The access attributes are: 3593 a - Any (default) 3594 r - Read-only 3595 o - Write-once 3596 c - Change-default 3597 3598 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3599 Define this to a list (string) to define the ".flags" 3600 environment variable in the default or embedded environment. 3601 3602 - CONFIG_ENV_FLAGS_LIST_STATIC 3603 Define this to a list (string) to define validation that 3604 should be done if an entry is not found in the ".flags" 3605 environment variable. To override a setting in the static 3606 list, simply add an entry for the same variable name to the 3607 ".flags" variable. 3608 3609 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 3610 regular expression. This allows multiple variables to define the same 3611 flags without explicitly listing them for each variable. 3612 3613- CONFIG_ENV_ACCESS_IGNORE_FORCE 3614 If defined, don't allow the -f switch to env set override variable 3615 access flags. 3616 3617- CONFIG_USE_STDINT 3618 If stdint.h is available with your toolchain you can define this 3619 option to enable it. You can provide option 'USE_STDINT=1' when 3620 building U-Boot to enable this. 3621 3622The following definitions that deal with the placement and management 3623of environment data (variable area); in general, we support the 3624following configurations: 3625 3626- CONFIG_BUILD_ENVCRC: 3627 3628 Builds up envcrc with the target environment so that external utils 3629 may easily extract it and embed it in final U-Boot images. 3630 3631- CONFIG_ENV_IS_IN_FLASH: 3632 3633 Define this if the environment is in flash memory. 3634 3635 a) The environment occupies one whole flash sector, which is 3636 "embedded" in the text segment with the U-Boot code. This 3637 happens usually with "bottom boot sector" or "top boot 3638 sector" type flash chips, which have several smaller 3639 sectors at the start or the end. For instance, such a 3640 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In 3641 such a case you would place the environment in one of the 3642 4 kB sectors - with U-Boot code before and after it. With 3643 "top boot sector" type flash chips, you would put the 3644 environment in one of the last sectors, leaving a gap 3645 between U-Boot and the environment. 3646 3647 - CONFIG_ENV_OFFSET: 3648 3649 Offset of environment data (variable area) to the 3650 beginning of flash memory; for instance, with bottom boot 3651 type flash chips the second sector can be used: the offset 3652 for this sector is given here. 3653 3654 CONFIG_ENV_OFFSET is used relative to CONFIG_SYS_FLASH_BASE. 3655 3656 - CONFIG_ENV_ADDR: 3657 3658 This is just another way to specify the start address of 3659 the flash sector containing the environment (instead of 3660 CONFIG_ENV_OFFSET). 3661 3662 - CONFIG_ENV_SECT_SIZE: 3663 3664 Size of the sector containing the environment. 3665 3666 3667 b) Sometimes flash chips have few, equal sized, BIG sectors. 3668 In such a case you don't want to spend a whole sector for 3669 the environment. 3670 3671 - CONFIG_ENV_SIZE: 3672 3673 If you use this in combination with CONFIG_ENV_IS_IN_FLASH 3674 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part 3675 of this flash sector for the environment. This saves 3676 memory for the RAM copy of the environment. 3677 3678 It may also save flash memory if you decide to use this 3679 when your environment is "embedded" within U-Boot code, 3680 since then the remainder of the flash sector could be used 3681 for U-Boot code. It should be pointed out that this is 3682 STRONGLY DISCOURAGED from a robustness point of view: 3683 updating the environment in flash makes it always 3684 necessary to erase the WHOLE sector. If something goes 3685 wrong before the contents has been restored from a copy in 3686 RAM, your target system will be dead. 3687 3688 - CONFIG_ENV_ADDR_REDUND 3689 CONFIG_ENV_SIZE_REDUND 3690 3691 These settings describe a second storage area used to hold 3692 a redundant copy of the environment data, so that there is 3693 a valid backup copy in case there is a power failure during 3694 a "saveenv" operation. 3695 3696BE CAREFUL! Any changes to the flash layout, and some changes to the 3697source code will make it necessary to adapt <board>/u-boot.lds* 3698accordingly! 3699 3700 3701- CONFIG_ENV_IS_IN_NVRAM: 3702 3703 Define this if you have some non-volatile memory device 3704 (NVRAM, battery buffered SRAM) which you want to use for the 3705 environment. 3706 3707 - CONFIG_ENV_ADDR: 3708 - CONFIG_ENV_SIZE: 3709 3710 These two #defines are used to determine the memory area you 3711 want to use for environment. It is assumed that this memory 3712 can just be read and written to, without any special 3713 provision. 3714 3715BE CAREFUL! The first access to the environment happens quite early 3716in U-Boot initialization (when we try to get the setting of for the 3717console baudrate). You *MUST* have mapped your NVRAM area then, or 3718U-Boot will hang. 3719 3720Please note that even with NVRAM we still use a copy of the 3721environment in RAM: we could work on NVRAM directly, but we want to 3722keep settings there always unmodified except somebody uses "saveenv" 3723to save the current settings. 3724 3725 3726- CONFIG_ENV_IS_IN_EEPROM: 3727 3728 Use this if you have an EEPROM or similar serial access 3729 device and a driver for it. 3730 3731 - CONFIG_ENV_OFFSET: 3732 - CONFIG_ENV_SIZE: 3733 3734 These two #defines specify the offset and size of the 3735 environment area within the total memory of your EEPROM. 3736 3737 - CONFIG_SYS_I2C_EEPROM_ADDR: 3738 If defined, specified the chip address of the EEPROM device. 3739 The default address is zero. 3740 3741 - CONFIG_SYS_I2C_EEPROM_BUS: 3742 If defined, specified the i2c bus of the EEPROM device. 3743 3744 - CONFIG_SYS_EEPROM_PAGE_WRITE_BITS: 3745 If defined, the number of bits used to address bytes in a 3746 single page in the EEPROM device. A 64 byte page, for example 3747 would require six bits. 3748 3749 - CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS: 3750 If defined, the number of milliseconds to delay between 3751 page writes. The default is zero milliseconds. 3752 3753 - CONFIG_SYS_I2C_EEPROM_ADDR_LEN: 3754 The length in bytes of the EEPROM memory array address. Note 3755 that this is NOT the chip address length! 3756 3757 - CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW: 3758 EEPROM chips that implement "address overflow" are ones 3759 like Catalyst 24WC04/08/16 which has 9/10/11 bits of 3760 address and the extra bits end up in the "chip address" bit 3761 slots. This makes a 24WC08 (1Kbyte) chip look like four 256 3762 byte chips. 3763 3764 Note that we consider the length of the address field to 3765 still be one byte because the extra address bits are hidden 3766 in the chip address. 3767 3768 - CONFIG_SYS_EEPROM_SIZE: 3769 The size in bytes of the EEPROM device. 3770 3771 - CONFIG_ENV_EEPROM_IS_ON_I2C 3772 define this, if you have I2C and SPI activated, and your 3773 EEPROM, which holds the environment, is on the I2C bus. 3774 3775 - CONFIG_I2C_ENV_EEPROM_BUS 3776 if you have an Environment on an EEPROM reached over 3777 I2C muxes, you can define here, how to reach this 3778 EEPROM. For example: 3779 3780 #define CONFIG_I2C_ENV_EEPROM_BUS 1 3781 3782 EEPROM which holds the environment, is reached over 3783 a pca9547 i2c mux with address 0x70, channel 3. 3784 3785- CONFIG_ENV_IS_IN_DATAFLASH: 3786 3787 Define this if you have a DataFlash memory device which you 3788 want to use for the environment. 3789 3790 - CONFIG_ENV_OFFSET: 3791 - CONFIG_ENV_ADDR: 3792 - CONFIG_ENV_SIZE: 3793 3794 These three #defines specify the offset and size of the 3795 environment area within the total memory of your DataFlash placed 3796 at the specified address. 3797 3798- CONFIG_ENV_IS_IN_SPI_FLASH: 3799 3800 Define this if you have a SPI Flash memory device which you 3801 want to use for the environment. 3802 3803 - CONFIG_ENV_OFFSET: 3804 - CONFIG_ENV_SIZE: 3805 3806 These two #defines specify the offset and size of the 3807 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be 3808 aligned to an erase sector boundary. 3809 3810 - CONFIG_ENV_SECT_SIZE: 3811 3812 Define the SPI flash's sector size. 3813 3814 - CONFIG_ENV_OFFSET_REDUND (optional): 3815 3816 This setting describes a second storage area of CONFIG_ENV_SIZE 3817 size used to hold a redundant copy of the environment data, so 3818 that there is a valid backup copy in case there is a power failure 3819 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3820 aligned to an erase sector boundary. 3821 3822 - CONFIG_ENV_SPI_BUS (optional): 3823 - CONFIG_ENV_SPI_CS (optional): 3824 3825 Define the SPI bus and chip select. If not defined they will be 0. 3826 3827 - CONFIG_ENV_SPI_MAX_HZ (optional): 3828 3829 Define the SPI max work clock. If not defined then use 1MHz. 3830 3831 - CONFIG_ENV_SPI_MODE (optional): 3832 3833 Define the SPI work mode. If not defined then use SPI_MODE_3. 3834 3835- CONFIG_ENV_IS_IN_REMOTE: 3836 3837 Define this if you have a remote memory space which you 3838 want to use for the local device's environment. 3839 3840 - CONFIG_ENV_ADDR: 3841 - CONFIG_ENV_SIZE: 3842 3843 These two #defines specify the address and size of the 3844 environment area within the remote memory space. The 3845 local device can get the environment from remote memory 3846 space by SRIO or PCIE links. 3847 3848BE CAREFUL! For some special cases, the local device can not use 3849"saveenv" command. For example, the local device will get the 3850environment stored in a remote NOR flash by SRIO or PCIE link, 3851but it can not erase, write this NOR flash by SRIO or PCIE interface. 3852 3853- CONFIG_ENV_IS_IN_NAND: 3854 3855 Define this if you have a NAND device which you want to use 3856 for the environment. 3857 3858 - CONFIG_ENV_OFFSET: 3859 - CONFIG_ENV_SIZE: 3860 3861 These two #defines specify the offset and size of the environment 3862 area within the first NAND device. CONFIG_ENV_OFFSET must be 3863 aligned to an erase block boundary. 3864 3865 - CONFIG_ENV_OFFSET_REDUND (optional): 3866 3867 This setting describes a second storage area of CONFIG_ENV_SIZE 3868 size used to hold a redundant copy of the environment data, so 3869 that there is a valid backup copy in case there is a power failure 3870 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be 3871 aligned to an erase block boundary. 3872 3873 - CONFIG_ENV_RANGE (optional): 3874 3875 Specifies the length of the region in which the environment 3876 can be written. This should be a multiple of the NAND device's 3877 block size. Specifying a range with more erase blocks than 3878 are needed to hold CONFIG_ENV_SIZE allows bad blocks within 3879 the range to be avoided. 3880 3881 - CONFIG_ENV_OFFSET_OOB (optional): 3882 3883 Enables support for dynamically retrieving the offset of the 3884 environment from block zero's out-of-band data. The 3885 "nand env.oob" command can be used to record this offset. 3886 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when 3887 using CONFIG_ENV_OFFSET_OOB. 3888 3889- CONFIG_NAND_ENV_DST 3890 3891 Defines address in RAM to which the nand_spl code should copy the 3892 environment. If redundant environment is used, it will be copied to 3893 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3894 3895- CONFIG_ENV_IS_IN_UBI: 3896 3897 Define this if you have an UBI volume that you want to use for the 3898 environment. This has the benefit of wear-leveling the environment 3899 accesses, which is important on NAND. 3900 3901 - CONFIG_ENV_UBI_PART: 3902 3903 Define this to a string that is the mtd partition containing the UBI. 3904 3905 - CONFIG_ENV_UBI_VOLUME: 3906 3907 Define this to the name of the volume that you want to store the 3908 environment in. 3909 3910 - CONFIG_ENV_UBI_VOLUME_REDUND: 3911 3912 Define this to the name of another volume to store a second copy of 3913 the environment in. This will enable redundant environments in UBI. 3914 It is assumed that both volumes are in the same MTD partition. 3915 3916 - CONFIG_UBI_SILENCE_MSG 3917 - CONFIG_UBIFS_SILENCE_MSG 3918 3919 You will probably want to define these to avoid a really noisy system 3920 when storing the env in UBI. 3921 3922- CONFIG_ENV_IS_IN_FAT: 3923 Define this if you want to use the FAT file system for the environment. 3924 3925 - FAT_ENV_INTERFACE: 3926 3927 Define this to a string that is the name of the block device. 3928 3929 - FAT_ENV_DEVICE_AND_PART: 3930 3931 Define this to a string to specify the partition of the device. It can 3932 be as following: 3933 3934 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1) 3935 - "D:P": device D partition P. Error occurs if device D has no 3936 partition table. 3937 - "D:0": device D. 3938 - "D" or "D:": device D partition 1 if device D has partition 3939 table, or the whole device D if has no partition 3940 table. 3941 - "D:auto": first partition in device D with bootable flag set. 3942 If none, first valid partition in device D. If no 3943 partition table then means device D. 3944 3945 - FAT_ENV_FILE: 3946 3947 It's a string of the FAT file name. This file use to store the 3948 environment. 3949 3950 - CONFIG_FAT_WRITE: 3951 This should be defined. Otherwise it cannot save the environment file. 3952 3953- CONFIG_ENV_IS_IN_MMC: 3954 3955 Define this if you have an MMC device which you want to use for the 3956 environment. 3957 3958 - CONFIG_SYS_MMC_ENV_DEV: 3959 3960 Specifies which MMC device the environment is stored in. 3961 3962 - CONFIG_SYS_MMC_ENV_PART (optional): 3963 3964 Specifies which MMC partition the environment is stored in. If not 3965 set, defaults to partition 0, the user area. Common values might be 3966 1 (first MMC boot partition), 2 (second MMC boot partition). 3967 3968 - CONFIG_ENV_OFFSET: 3969 - CONFIG_ENV_SIZE: 3970 3971 These two #defines specify the offset and size of the environment 3972 area within the specified MMC device. 3973 3974 If offset is positive (the usual case), it is treated as relative to 3975 the start of the MMC partition. If offset is negative, it is treated 3976 as relative to the end of the MMC partition. This can be useful if 3977 your board may be fitted with different MMC devices, which have 3978 different sizes for the MMC partitions, and you always want the 3979 environment placed at the very end of the partition, to leave the 3980 maximum possible space before it, to store other data. 3981 3982 These two values are in units of bytes, but must be aligned to an 3983 MMC sector boundary. 3984 3985 - CONFIG_ENV_OFFSET_REDUND (optional): 3986 3987 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to 3988 hold a redundant copy of the environment data. This provides a 3989 valid backup copy in case the other copy is corrupted, e.g. due 3990 to a power failure during a "saveenv" operation. 3991 3992 This value may also be positive or negative; this is handled in the 3993 same way as CONFIG_ENV_OFFSET. 3994 3995 This value is also in units of bytes, but must also be aligned to 3996 an MMC sector boundary. 3997 3998 - CONFIG_ENV_SIZE_REDUND (optional): 3999 4000 This value need not be set, even when CONFIG_ENV_OFFSET_REDUND is 4001 set. If this value is set, it must be set to the same value as 4002 CONFIG_ENV_SIZE. 4003 4004- CONFIG_SYS_SPI_INIT_OFFSET 4005 4006 Defines offset to the initial SPI buffer area in DPRAM. The 4007 area is used at an early stage (ROM part) if the environment 4008 is configured to reside in the SPI EEPROM: We need a 520 byte 4009 scratch DPRAM area. It is used between the two initialization 4010 calls (spi_init_f() and spi_init_r()). A value of 0xB00 seems 4011 to be a good choice since it makes it far enough from the 4012 start of the data area as well as from the stack pointer. 4013 4014Please note that the environment is read-only until the monitor 4015has been relocated to RAM and a RAM copy of the environment has been 4016created; also, when using EEPROM you will have to use getenv_f() 4017until then to read environment variables. 4018 4019The environment is protected by a CRC32 checksum. Before the monitor 4020is relocated into RAM, as a result of a bad CRC you will be working 4021with the compiled-in default environment - *silently*!!! [This is 4022necessary, because the first environment variable we need is the 4023"baudrate" setting for the console - if we have a bad CRC, we don't 4024have any device yet where we could complain.] 4025 4026Note: once the monitor has been relocated, then it will complain if 4027the default environment is used; a new CRC is computed as soon as you 4028use the "saveenv" command to store a valid environment. 4029 4030- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 4031 Echo the inverted Ethernet link state to the fault LED. 4032 4033 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 4034 also needs to be defined. 4035 4036- CONFIG_SYS_FAULT_MII_ADDR: 4037 MII address of the PHY to check for the Ethernet link state. 4038 4039- CONFIG_NS16550_MIN_FUNCTIONS: 4040 Define this if you desire to only have use of the NS16550_init 4041 and NS16550_putc functions for the serial driver located at 4042 drivers/serial/ns16550.c. This option is useful for saving 4043 space for already greatly restricted images, including but not 4044 limited to NAND_SPL configurations. 4045 4046- CONFIG_DISPLAY_BOARDINFO 4047 Display information about the board that U-Boot is running on 4048 when U-Boot starts up. The board function checkboard() is called 4049 to do this. 4050 4051- CONFIG_DISPLAY_BOARDINFO_LATE 4052 Similar to the previous option, but display this information 4053 later, once stdio is running and output goes to the LCD, if 4054 present. 4055 4056- CONFIG_BOARD_SIZE_LIMIT: 4057 Maximum size of the U-Boot image. When defined, the 4058 build system checks that the actual size does not 4059 exceed it. 4060 4061Low Level (hardware related) configuration options: 4062--------------------------------------------------- 4063 4064- CONFIG_SYS_CACHELINE_SIZE: 4065 Cache Line Size of the CPU. 4066 4067- CONFIG_SYS_DEFAULT_IMMR: 4068 Default address of the IMMR after system reset. 4069 4070 Needed on some 8260 systems (MPC8260ADS, PQ2FADS-ZU, 4071 and RPXsuper) to be able to adjust the position of 4072 the IMMR register after a reset. 4073 4074- CONFIG_SYS_CCSRBAR_DEFAULT: 4075 Default (power-on reset) physical address of CCSR on Freescale 4076 PowerPC SOCs. 4077 4078- CONFIG_SYS_CCSRBAR: 4079 Virtual address of CCSR. On a 32-bit build, this is typically 4080 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 4081 4082 CONFIG_SYS_DEFAULT_IMMR must also be set to this value, 4083 for cross-platform code that uses that macro instead. 4084 4085- CONFIG_SYS_CCSRBAR_PHYS: 4086 Physical address of CCSR. CCSR can be relocated to a new 4087 physical address, if desired. In this case, this macro should 4088 be set to that address. Otherwise, it should be set to the 4089 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 4090 is typically relocated on 36-bit builds. It is recommended 4091 that this macro be defined via the _HIGH and _LOW macros: 4092 4093 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 4094 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 4095 4096- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 4097 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 4098 either 0 (32-bit build) or 0xF (36-bit build). This macro is 4099 used in assembly code, so it must not contain typecasts or 4100 integer size suffixes (e.g. "ULL"). 4101 4102- CONFIG_SYS_CCSRBAR_PHYS_LOW: 4103 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 4104 used in assembly code, so it must not contain typecasts or 4105 integer size suffixes (e.g. "ULL"). 4106 4107- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 4108 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 4109 forced to a value that ensures that CCSR is not relocated. 4110 4111- Floppy Disk Support: 4112 CONFIG_SYS_FDC_DRIVE_NUMBER 4113 4114 the default drive number (default value 0) 4115 4116 CONFIG_SYS_ISA_IO_STRIDE 4117 4118 defines the spacing between FDC chipset registers 4119 (default value 1) 4120 4121 CONFIG_SYS_ISA_IO_OFFSET 4122 4123 defines the offset of register from address. It 4124 depends on which part of the data bus is connected to 4125 the FDC chipset. (default value 0) 4126 4127 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 4128 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 4129 default value. 4130 4131 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 4132 fdc_hw_init() is called at the beginning of the FDC 4133 setup. fdc_hw_init() must be provided by the board 4134 source code. It is used to make hardware-dependent 4135 initializations. 4136 4137- CONFIG_IDE_AHB: 4138 Most IDE controllers were designed to be connected with PCI 4139 interface. Only few of them were designed for AHB interface. 4140 When software is doing ATA command and data transfer to 4141 IDE devices through IDE-AHB controller, some additional 4142 registers accessing to these kind of IDE-AHB controller 4143 is required. 4144 4145- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 4146 DO NOT CHANGE unless you know exactly what you're 4147 doing! (11-4) [MPC8xx/82xx systems only] 4148 4149- CONFIG_SYS_INIT_RAM_ADDR: 4150 4151 Start address of memory area that can be used for 4152 initial data and stack; please note that this must be 4153 writable memory that is working WITHOUT special 4154 initialization, i. e. you CANNOT use normal RAM which 4155 will become available only after programming the 4156 memory controller and running certain initialization 4157 sequences. 4158 4159 U-Boot uses the following memory types: 4160 - MPC8xx and MPC8260: IMMR (internal memory of the CPU) 4161 - MPC824X: data cache 4162 - PPC4xx: data cache 4163 4164- CONFIG_SYS_GBL_DATA_OFFSET: 4165 4166 Offset of the initial data structure in the memory 4167 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 4168 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 4169 data is located at the end of the available space 4170 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 4171 GENERATED_GBL_DATA_SIZE), and the initial stack is just 4172 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 4173 CONFIG_SYS_GBL_DATA_OFFSET) downward. 4174 4175 Note: 4176 On the MPC824X (or other systems that use the data 4177 cache for initial memory) the address chosen for 4178 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 4179 point to an otherwise UNUSED address space between 4180 the top of RAM and the start of the PCI space. 4181 4182- CONFIG_SYS_SIUMCR: SIU Module Configuration (11-6) 4183 4184- CONFIG_SYS_SYPCR: System Protection Control (11-9) 4185 4186- CONFIG_SYS_TBSCR: Time Base Status and Control (11-26) 4187 4188- CONFIG_SYS_PISCR: Periodic Interrupt Status and Control (11-31) 4189 4190- CONFIG_SYS_PLPRCR: PLL, Low-Power, and Reset Control Register (15-30) 4191 4192- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 4193 4194- CONFIG_SYS_OR_TIMING_SDRAM: 4195 SDRAM timing 4196 4197- CONFIG_SYS_MAMR_PTA: 4198 periodic timer for refresh 4199 4200- CONFIG_SYS_DER: Debug Event Register (37-47) 4201 4202- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 4203 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 4204 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 4205 CONFIG_SYS_BR1_PRELIM: 4206 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 4207 4208- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 4209 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 4210 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 4211 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 4212 4213- CONFIG_SYS_MAMR_PTA, CONFIG_SYS_MPTPR_2BK_4K, CONFIG_SYS_MPTPR_1BK_4K, CONFIG_SYS_MPTPR_2BK_8K, 4214 CONFIG_SYS_MPTPR_1BK_8K, CONFIG_SYS_MAMR_8COL, CONFIG_SYS_MAMR_9COL: 4215 Machine Mode Register and Memory Periodic Timer 4216 Prescaler definitions (SDRAM timing) 4217 4218- CONFIG_SYS_I2C_UCODE_PATCH, CONFIG_SYS_I2C_DPMEM_OFFSET [0x1FC0]: 4219 enable I2C microcode relocation patch (MPC8xx); 4220 define relocation offset in DPRAM [DSP2] 4221 4222- CONFIG_SYS_SMC_UCODE_PATCH, CONFIG_SYS_SMC_DPMEM_OFFSET [0x1FC0]: 4223 enable SMC microcode relocation patch (MPC8xx); 4224 define relocation offset in DPRAM [SMC1] 4225 4226- CONFIG_SYS_SPI_UCODE_PATCH, CONFIG_SYS_SPI_DPMEM_OFFSET [0x1FC0]: 4227 enable SPI microcode relocation patch (MPC8xx); 4228 define relocation offset in DPRAM [SCC4] 4229 4230- CONFIG_SYS_CPM_POST_WORD_ADDR: (MPC8xx, MPC8260 only) 4231 Offset of the bootmode word in DPRAM used by post 4232 (Power On Self Tests). This definition overrides 4233 #define'd default value in commproc.h resp. 4234 cpm_8260.h. 4235 4236- CONFIG_SYS_PCI_SLV_MEM_LOCAL, CONFIG_SYS_PCI_SLV_MEM_BUS, CONFIG_SYS_PICMR0_MASK_ATTRIB, 4237 CONFIG_SYS_PCI_MSTR0_LOCAL, CONFIG_SYS_PCIMSK0_MASK, CONFIG_SYS_PCI_MSTR1_LOCAL, 4238 CONFIG_SYS_PCIMSK1_MASK, CONFIG_SYS_PCI_MSTR_MEM_LOCAL, CONFIG_SYS_PCI_MSTR_MEM_BUS, 4239 CONFIG_SYS_CPU_PCI_MEM_START, CONFIG_SYS_PCI_MSTR_MEM_SIZE, CONFIG_SYS_POCMR0_MASK_ATTRIB, 4240 CONFIG_SYS_PCI_MSTR_MEMIO_LOCAL, CONFIG_SYS_PCI_MSTR_MEMIO_BUS, CPU_PCI_MEMIO_START, 4241 CONFIG_SYS_PCI_MSTR_MEMIO_SIZE, CONFIG_SYS_POCMR1_MASK_ATTRIB, CONFIG_SYS_PCI_MSTR_IO_LOCAL, 4242 CONFIG_SYS_PCI_MSTR_IO_BUS, CONFIG_SYS_CPU_PCI_IO_START, CONFIG_SYS_PCI_MSTR_IO_SIZE, 4243 CONFIG_SYS_POCMR2_MASK_ATTRIB: (MPC826x only) 4244 Overrides the default PCI memory map in arch/powerpc/cpu/mpc8260/pci.c if set. 4245 4246- CONFIG_PCI_DISABLE_PCIE: 4247 Disable PCI-Express on systems where it is supported but not 4248 required. 4249 4250- CONFIG_PCI_ENUM_ONLY 4251 Only scan through and get the devices on the buses. 4252 Don't do any setup work, presumably because someone or 4253 something has already done it, and we don't need to do it 4254 a second time. Useful for platforms that are pre-booted 4255 by coreboot or similar. 4256 4257- CONFIG_PCI_INDIRECT_BRIDGE: 4258 Enable support for indirect PCI bridges. 4259 4260- CONFIG_SYS_SRIO: 4261 Chip has SRIO or not 4262 4263- CONFIG_SRIO1: 4264 Board has SRIO 1 port available 4265 4266- CONFIG_SRIO2: 4267 Board has SRIO 2 port available 4268 4269- CONFIG_SRIO_PCIE_BOOT_MASTER 4270 Board can support master function for Boot from SRIO and PCIE 4271 4272- CONFIG_SYS_SRIOn_MEM_VIRT: 4273 Virtual Address of SRIO port 'n' memory region 4274 4275- CONFIG_SYS_SRIOn_MEM_PHYS: 4276 Physical Address of SRIO port 'n' memory region 4277 4278- CONFIG_SYS_SRIOn_MEM_SIZE: 4279 Size of SRIO port 'n' memory region 4280 4281- CONFIG_SYS_NAND_BUSWIDTH_16BIT 4282 Defined to tell the NAND controller that the NAND chip is using 4283 a 16 bit bus. 4284 Not all NAND drivers use this symbol. 4285 Example of drivers that use it: 4286 - drivers/mtd/nand/ndfc.c 4287 - drivers/mtd/nand/mxc_nand.c 4288 4289- CONFIG_SYS_NDFC_EBC0_CFG 4290 Sets the EBC0_CFG register for the NDFC. If not defined 4291 a default value will be used. 4292 4293- CONFIG_SPD_EEPROM 4294 Get DDR timing information from an I2C EEPROM. Common 4295 with pluggable memory modules such as SODIMMs 4296 4297 SPD_EEPROM_ADDRESS 4298 I2C address of the SPD EEPROM 4299 4300- CONFIG_SYS_SPD_BUS_NUM 4301 If SPD EEPROM is on an I2C bus other than the first 4302 one, specify here. Note that the value must resolve 4303 to something your driver can deal with. 4304 4305- CONFIG_SYS_DDR_RAW_TIMING 4306 Get DDR timing information from other than SPD. Common with 4307 soldered DDR chips onboard without SPD. DDR raw timing 4308 parameters are extracted from datasheet and hard-coded into 4309 header files or board specific files. 4310 4311- CONFIG_FSL_DDR_INTERACTIVE 4312 Enable interactive DDR debugging. See doc/README.fsl-ddr. 4313 4314- CONFIG_FSL_DDR_SYNC_REFRESH 4315 Enable sync of refresh for multiple controllers. 4316 4317- CONFIG_FSL_DDR_BIST 4318 Enable built-in memory test for Freescale DDR controllers. 4319 4320- CONFIG_SYS_83XX_DDR_USES_CS0 4321 Only for 83xx systems. If specified, then DDR should 4322 be configured using CS0 and CS1 instead of CS2 and CS3. 4323 4324- CONFIG_ETHER_ON_FEC[12] 4325 Define to enable FEC[12] on a 8xx series processor. 4326 4327- CONFIG_FEC[12]_PHY 4328 Define to the hardcoded PHY address which corresponds 4329 to the given FEC; i. e. 4330 #define CONFIG_FEC1_PHY 4 4331 means that the PHY with address 4 is connected to FEC1 4332 4333 When set to -1, means to probe for first available. 4334 4335- CONFIG_FEC[12]_PHY_NORXERR 4336 The PHY does not have a RXERR line (RMII only). 4337 (so program the FEC to ignore it). 4338 4339- CONFIG_RMII 4340 Enable RMII mode for all FECs. 4341 Note that this is a global option, we can't 4342 have one FEC in standard MII mode and another in RMII mode. 4343 4344- CONFIG_CRC32_VERIFY 4345 Add a verify option to the crc32 command. 4346 The syntax is: 4347 4348 => crc32 -v <address> <count> <crc32> 4349 4350 Where address/count indicate a memory area 4351 and crc32 is the correct crc32 which the 4352 area should have. 4353 4354- CONFIG_LOOPW 4355 Add the "loopw" memory command. This only takes effect if 4356 the memory commands are activated globally (CONFIG_CMD_MEM). 4357 4358- CONFIG_MX_CYCLIC 4359 Add the "mdc" and "mwc" memory commands. These are cyclic 4360 "md/mw" commands. 4361 Examples: 4362 4363 => mdc.b 10 4 500 4364 This command will print 4 bytes (10,11,12,13) each 500 ms. 4365 4366 => mwc.l 100 12345678 10 4367 This command will write 12345678 to address 100 all 10 ms. 4368 4369 This only takes effect if the memory commands are activated 4370 globally (CONFIG_CMD_MEM). 4371 4372- CONFIG_SKIP_LOWLEVEL_INIT 4373 [ARM, NDS32, MIPS only] If this variable is defined, then certain 4374 low level initializations (like setting up the memory 4375 controller) are omitted and/or U-Boot does not 4376 relocate itself into RAM. 4377 4378 Normally this variable MUST NOT be defined. The only 4379 exception is when U-Boot is loaded (to RAM) by some 4380 other boot loader or by a debugger which performs 4381 these initializations itself. 4382 4383- CONFIG_SKIP_LOWLEVEL_INIT_ONLY 4384 [ARM926EJ-S only] This allows just the call to lowlevel_init() 4385 to be skipped. The normal CP15 init (such as enabling the 4386 instruction cache) is still performed. 4387 4388- CONFIG_SPL_BUILD 4389 Modifies the behaviour of start.S when compiling a loader 4390 that is executed before the actual U-Boot. E.g. when 4391 compiling a NAND SPL. 4392 4393- CONFIG_TPL_BUILD 4394 Modifies the behaviour of start.S when compiling a loader 4395 that is executed after the SPL and before the actual U-Boot. 4396 It is loaded by the SPL. 4397 4398- CONFIG_SYS_MPC85XX_NO_RESETVEC 4399 Only for 85xx systems. If this variable is specified, the section 4400 .resetvec is not kept and the section .bootpg is placed in the 4401 previous 4k of the .text section. 4402 4403- CONFIG_ARCH_MAP_SYSMEM 4404 Generally U-Boot (and in particular the md command) uses 4405 effective address. It is therefore not necessary to regard 4406 U-Boot address as virtual addresses that need to be translated 4407 to physical addresses. However, sandbox requires this, since 4408 it maintains its own little RAM buffer which contains all 4409 addressable memory. This option causes some memory accesses 4410 to be mapped through map_sysmem() / unmap_sysmem(). 4411 4412- CONFIG_X86_RESET_VECTOR 4413 If defined, the x86 reset vector code is included. This is not 4414 needed when U-Boot is running from Coreboot. 4415 4416- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 4417 Enables the RTC32K OSC on AM33xx based plattforms 4418 4419- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 4420 Option to disable subpage write in NAND driver 4421 driver that uses this: 4422 drivers/mtd/nand/davinci_nand.c 4423 4424Freescale QE/FMAN Firmware Support: 4425----------------------------------- 4426 4427The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 4428loading of "firmware", which is encoded in the QE firmware binary format. 4429This firmware often needs to be loaded during U-Boot booting, so macros 4430are used to identify the storage device (NOR flash, SPI, etc) and the address 4431within that device. 4432 4433- CONFIG_SYS_FMAN_FW_ADDR 4434 The address in the storage device where the FMAN microcode is located. The 4435 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4436 is also specified. 4437 4438- CONFIG_SYS_QE_FW_ADDR 4439 The address in the storage device where the QE microcode is located. The 4440 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 4441 is also specified. 4442 4443- CONFIG_SYS_QE_FMAN_FW_LENGTH 4444 The maximum possible size of the firmware. The firmware binary format 4445 has a field that specifies the actual size of the firmware, but it 4446 might not be possible to read any part of the firmware unless some 4447 local storage is allocated to hold the entire firmware first. 4448 4449- CONFIG_SYS_QE_FMAN_FW_IN_NOR 4450 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 4451 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 4452 virtual address in NOR flash. 4453 4454- CONFIG_SYS_QE_FMAN_FW_IN_NAND 4455 Specifies that QE/FMAN firmware is located in NAND flash. 4456 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 4457 4458- CONFIG_SYS_QE_FMAN_FW_IN_MMC 4459 Specifies that QE/FMAN firmware is located on the primary SD/MMC 4460 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 4461 4462- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 4463 Specifies that QE/FMAN firmware is located in the remote (master) 4464 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 4465 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 4466 window->master inbound window->master LAW->the ucode address in 4467 master's memory space. 4468 4469Freescale Layerscape Management Complex Firmware Support: 4470--------------------------------------------------------- 4471The Freescale Layerscape Management Complex (MC) supports the loading of 4472"firmware". 4473This firmware often needs to be loaded during U-Boot booting, so macros 4474are used to identify the storage device (NOR flash, SPI, etc) and the address 4475within that device. 4476 4477- CONFIG_FSL_MC_ENET 4478 Enable the MC driver for Layerscape SoCs. 4479 4480Freescale Layerscape Debug Server Support: 4481------------------------------------------- 4482The Freescale Layerscape Debug Server Support supports the loading of 4483"Debug Server firmware" and triggering SP boot-rom. 4484This firmware often needs to be loaded during U-Boot booting. 4485 4486- CONFIG_SYS_MC_RSV_MEM_ALIGN 4487 Define alignment of reserved memory MC requires 4488 4489Reproducible builds 4490------------------- 4491 4492In order to achieve reproducible builds, timestamps used in the U-Boot build 4493process have to be set to a fixed value. 4494 4495This is done using the SOURCE_DATE_EPOCH environment variable. 4496SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 4497option for U-Boot or an environment variable in U-Boot. 4498 4499SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 4500 4501Building the Software: 4502====================== 4503 4504Building U-Boot has been tested in several native build environments 4505and in many different cross environments. Of course we cannot support 4506all possibly existing versions of cross development tools in all 4507(potentially obsolete) versions. In case of tool chain problems we 4508recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 4509which is extensively used to build and test U-Boot. 4510 4511If you are not using a native environment, it is assumed that you 4512have GNU cross compiling tools available in your path. In this case, 4513you must set the environment variable CROSS_COMPILE in your shell. 4514Note that no changes to the Makefile or any other source files are 4515necessary. For example using the ELDK on a 4xx CPU, please enter: 4516 4517 $ CROSS_COMPILE=ppc_4xx- 4518 $ export CROSS_COMPILE 4519 4520Note: If you wish to generate Windows versions of the utilities in 4521 the tools directory you can use the MinGW toolchain 4522 (http://www.mingw.org). Set your HOST tools to the MinGW 4523 toolchain and execute 'make tools'. For example: 4524 4525 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 4526 4527 Binaries such as tools/mkimage.exe will be created which can 4528 be executed on computers running Windows. 4529 4530U-Boot is intended to be simple to build. After installing the 4531sources you must configure U-Boot for one specific board type. This 4532is done by typing: 4533 4534 make NAME_defconfig 4535 4536where "NAME_defconfig" is the name of one of the existing configu- 4537rations; see boards.cfg for supported names. 4538 4539Note: for some board special configuration names may exist; check if 4540 additional information is available from the board vendor; for 4541 instance, the TQM823L systems are available without (standard) 4542 or with LCD support. You can select such additional "features" 4543 when choosing the configuration, i. e. 4544 4545 make TQM823L_defconfig 4546 - will configure for a plain TQM823L, i. e. no LCD support 4547 4548 make TQM823L_LCD_defconfig 4549 - will configure for a TQM823L with U-Boot console on LCD 4550 4551 etc. 4552 4553 4554Finally, type "make all", and you should get some working U-Boot 4555images ready for download to / installation on your system: 4556 4557- "u-boot.bin" is a raw binary image 4558- "u-boot" is an image in ELF binary format 4559- "u-boot.srec" is in Motorola S-Record format 4560 4561By default the build is performed locally and the objects are saved 4562in the source directory. One of the two methods can be used to change 4563this behavior and build U-Boot to some external directory: 4564 45651. Add O= to the make command line invocations: 4566 4567 make O=/tmp/build distclean 4568 make O=/tmp/build NAME_defconfig 4569 make O=/tmp/build all 4570 45712. Set environment variable KBUILD_OUTPUT to point to the desired location: 4572 4573 export KBUILD_OUTPUT=/tmp/build 4574 make distclean 4575 make NAME_defconfig 4576 make all 4577 4578Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 4579variable. 4580 4581 4582Please be aware that the Makefiles assume you are using GNU make, so 4583for instance on NetBSD you might need to use "gmake" instead of 4584native "make". 4585 4586 4587If the system board that you have is not listed, then you will need 4588to port U-Boot to your hardware platform. To do this, follow these 4589steps: 4590 45911. Create a new directory to hold your board specific code. Add any 4592 files you need. In your board directory, you will need at least 4593 the "Makefile" and a "<board>.c". 45942. Create a new configuration file "include/configs/<board>.h" for 4595 your board. 45963. If you're porting U-Boot to a new CPU, then also create a new 4597 directory to hold your CPU specific code. Add any files you need. 45984. Run "make <board>_defconfig" with your new name. 45995. Type "make", and you should get a working "u-boot.srec" file 4600 to be installed on your target system. 46016. Debug and solve any problems that might arise. 4602 [Of course, this last step is much harder than it sounds.] 4603 4604 4605Testing of U-Boot Modifications, Ports to New Hardware, etc.: 4606============================================================== 4607 4608If you have modified U-Boot sources (for instance added a new board 4609or support for new devices, a new CPU, etc.) you are expected to 4610provide feedback to the other developers. The feedback normally takes 4611the form of a "patch", i. e. a context diff against a certain (latest 4612official or latest in the git repository) version of U-Boot sources. 4613 4614But before you submit such a patch, please verify that your modifi- 4615cation did not break existing code. At least make sure that *ALL* of 4616the supported boards compile WITHOUT ANY compiler warnings. To do so, 4617just run the buildman script (tools/buildman/buildman), which will 4618configure and build U-Boot for ALL supported system. Be warned, this 4619will take a while. Please see the buildman README, or run 'buildman -H' 4620for documentation. 4621 4622 4623See also "U-Boot Porting Guide" below. 4624 4625 4626Monitor Commands - Overview: 4627============================ 4628 4629go - start application at address 'addr' 4630run - run commands in an environment variable 4631bootm - boot application image from memory 4632bootp - boot image via network using BootP/TFTP protocol 4633bootz - boot zImage from memory 4634tftpboot- boot image via network using TFTP protocol 4635 and env variables "ipaddr" and "serverip" 4636 (and eventually "gatewayip") 4637tftpput - upload a file via network using TFTP protocol 4638rarpboot- boot image via network using RARP/TFTP protocol 4639diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 4640loads - load S-Record file over serial line 4641loadb - load binary file over serial line (kermit mode) 4642md - memory display 4643mm - memory modify (auto-incrementing) 4644nm - memory modify (constant address) 4645mw - memory write (fill) 4646cp - memory copy 4647cmp - memory compare 4648crc32 - checksum calculation 4649i2c - I2C sub-system 4650sspi - SPI utility commands 4651base - print or set address offset 4652printenv- print environment variables 4653setenv - set environment variables 4654saveenv - save environment variables to persistent storage 4655protect - enable or disable FLASH write protection 4656erase - erase FLASH memory 4657flinfo - print FLASH memory information 4658nand - NAND memory operations (see doc/README.nand) 4659bdinfo - print Board Info structure 4660iminfo - print header information for application image 4661coninfo - print console devices and informations 4662ide - IDE sub-system 4663loop - infinite loop on address range 4664loopw - infinite write loop on address range 4665mtest - simple RAM test 4666icache - enable or disable instruction cache 4667dcache - enable or disable data cache 4668reset - Perform RESET of the CPU 4669echo - echo args to console 4670version - print monitor version 4671help - print online help 4672? - alias for 'help' 4673 4674 4675Monitor Commands - Detailed Description: 4676======================================== 4677 4678TODO. 4679 4680For now: just type "help <command>". 4681 4682 4683Environment Variables: 4684====================== 4685 4686U-Boot supports user configuration using Environment Variables which 4687can be made persistent by saving to Flash memory. 4688 4689Environment Variables are set using "setenv", printed using 4690"printenv", and saved to Flash using "saveenv". Using "setenv" 4691without a value can be used to delete a variable from the 4692environment. As long as you don't save the environment you are 4693working with an in-memory copy. In case the Flash area containing the 4694environment is erased by accident, a default environment is provided. 4695 4696Some configuration options can be set using Environment Variables. 4697 4698List of environment variables (most likely not complete): 4699 4700 baudrate - see CONFIG_BAUDRATE 4701 4702 bootdelay - see CONFIG_BOOTDELAY 4703 4704 bootcmd - see CONFIG_BOOTCOMMAND 4705 4706 bootargs - Boot arguments when booting an RTOS image 4707 4708 bootfile - Name of the image to load with TFTP 4709 4710 bootm_low - Memory range available for image processing in the bootm 4711 command can be restricted. This variable is given as 4712 a hexadecimal number and defines lowest address allowed 4713 for use by the bootm command. See also "bootm_size" 4714 environment variable. Address defined by "bootm_low" is 4715 also the base of the initial memory mapping for the Linux 4716 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 4717 bootm_mapsize. 4718 4719 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 4720 This variable is given as a hexadecimal number and it 4721 defines the size of the memory region starting at base 4722 address bootm_low that is accessible by the Linux kernel 4723 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 4724 as the default value if it is defined, and bootm_size is 4725 used otherwise. 4726 4727 bootm_size - Memory range available for image processing in the bootm 4728 command can be restricted. This variable is given as 4729 a hexadecimal number and defines the size of the region 4730 allowed for use by the bootm command. See also "bootm_low" 4731 environment variable. 4732 4733 updatefile - Location of the software update file on a TFTP server, used 4734 by the automatic software update feature. Please refer to 4735 documentation in doc/README.update for more details. 4736 4737 autoload - if set to "no" (any string beginning with 'n'), 4738 "bootp" will just load perform a lookup of the 4739 configuration from the BOOTP server, but not try to 4740 load any image using TFTP 4741 4742 autostart - if set to "yes", an image loaded using the "bootp", 4743 "rarpboot", "tftpboot" or "diskboot" commands will 4744 be automatically started (by internally calling 4745 "bootm") 4746 4747 If set to "no", a standalone image passed to the 4748 "bootm" command will be copied to the load address 4749 (and eventually uncompressed), but NOT be started. 4750 This can be used to load and uncompress arbitrary 4751 data. 4752 4753 fdt_high - if set this restricts the maximum address that the 4754 flattened device tree will be copied into upon boot. 4755 For example, if you have a system with 1 GB memory 4756 at physical address 0x10000000, while Linux kernel 4757 only recognizes the first 704 MB as low memory, you 4758 may need to set fdt_high as 0x3C000000 to have the 4759 device tree blob be copied to the maximum address 4760 of the 704 MB low memory, so that Linux kernel can 4761 access it during the boot procedure. 4762 4763 If this is set to the special value 0xFFFFFFFF then 4764 the fdt will not be copied at all on boot. For this 4765 to work it must reside in writable memory, have 4766 sufficient padding on the end of it for u-boot to 4767 add the information it needs into it, and the memory 4768 must be accessible by the kernel. 4769 4770 fdtcontroladdr- if set this is the address of the control flattened 4771 device tree used by U-Boot when CONFIG_OF_CONTROL is 4772 defined. 4773 4774 i2cfast - (PPC405GP|PPC405EP only) 4775 if set to 'y' configures Linux I2C driver for fast 4776 mode (400kHZ). This environment variable is used in 4777 initialization code. So, for changes to be effective 4778 it must be saved and board must be reset. 4779 4780 initrd_high - restrict positioning of initrd images: 4781 If this variable is not set, initrd images will be 4782 copied to the highest possible address in RAM; this 4783 is usually what you want since it allows for 4784 maximum initrd size. If for some reason you want to 4785 make sure that the initrd image is loaded below the 4786 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 4787 variable to a value of "no" or "off" or "0". 4788 Alternatively, you can set it to a maximum upper 4789 address to use (U-Boot will still check that it 4790 does not overwrite the U-Boot stack and data). 4791 4792 For instance, when you have a system with 16 MB 4793 RAM, and want to reserve 4 MB from use by Linux, 4794 you can do this by adding "mem=12M" to the value of 4795 the "bootargs" variable. However, now you must make 4796 sure that the initrd image is placed in the first 4797 12 MB as well - this can be done with 4798 4799 setenv initrd_high 00c00000 4800 4801 If you set initrd_high to 0xFFFFFFFF, this is an 4802 indication to U-Boot that all addresses are legal 4803 for the Linux kernel, including addresses in flash 4804 memory. In this case U-Boot will NOT COPY the 4805 ramdisk at all. This may be useful to reduce the 4806 boot time on your system, but requires that this 4807 feature is supported by your Linux kernel. 4808 4809 ipaddr - IP address; needed for tftpboot command 4810 4811 loadaddr - Default load address for commands like "bootp", 4812 "rarpboot", "tftpboot", "loadb" or "diskboot" 4813 4814 loads_echo - see CONFIG_LOADS_ECHO 4815 4816 serverip - TFTP server IP address; needed for tftpboot command 4817 4818 bootretry - see CONFIG_BOOT_RETRY_TIME 4819 4820 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 4821 4822 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 4823 4824 ethprime - controls which interface is used first. 4825 4826 ethact - controls which interface is currently active. 4827 For example you can do the following 4828 4829 => setenv ethact FEC 4830 => ping 192.168.0.1 # traffic sent on FEC 4831 => setenv ethact SCC 4832 => ping 10.0.0.1 # traffic sent on SCC 4833 4834 ethrotate - When set to "no" U-Boot does not go through all 4835 available network interfaces. 4836 It just stays at the currently selected interface. 4837 4838 netretry - When set to "no" each network operation will 4839 either succeed or fail without retrying. 4840 When set to "once" the network operation will 4841 fail when all the available network interfaces 4842 are tried once without success. 4843 Useful on scripts which control the retry operation 4844 themselves. 4845 4846 npe_ucode - set load address for the NPE microcode 4847 4848 silent_linux - If set then Linux will be told to boot silently, by 4849 changing the console to be empty. If "yes" it will be 4850 made silent. If "no" it will not be made silent. If 4851 unset, then it will be made silent if the U-Boot console 4852 is silent. 4853 4854 tftpsrcp - If this is set, the value is used for TFTP's 4855 UDP source port. 4856 4857 tftpdstp - If this is set, the value is used for TFTP's UDP 4858 destination port instead of the Well Know Port 69. 4859 4860 tftpblocksize - Block size to use for TFTP transfers; if not set, 4861 we use the TFTP server's default block size 4862 4863 tftptimeout - Retransmission timeout for TFTP packets (in milli- 4864 seconds, minimum value is 1000 = 1 second). Defines 4865 when a packet is considered to be lost so it has to 4866 be retransmitted. The default is 5000 = 5 seconds. 4867 Lowering this value may make downloads succeed 4868 faster in networks with high packet loss rates or 4869 with unreliable TFTP servers. 4870 4871 tftptimeoutcountmax - maximum count of TFTP timeouts (no 4872 unit, minimum value = 0). Defines how many timeouts 4873 can happen during a single file transfer before that 4874 transfer is aborted. The default is 10, and 0 means 4875 'no timeouts allowed'. Increasing this value may help 4876 downloads succeed with high packet loss rates, or with 4877 unreliable TFTP servers or client hardware. 4878 4879 vlan - When set to a value < 4095 the traffic over 4880 Ethernet is encapsulated/received over 802.1q 4881 VLAN tagged frames. 4882 4883 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 4884 Unsigned value, in milliseconds. If not set, the period will 4885 be either the default (28000), or a value based on 4886 CONFIG_NET_RETRY_COUNT, if defined. This value has 4887 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 4888 4889The following image location variables contain the location of images 4890used in booting. The "Image" column gives the role of the image and is 4891not an environment variable name. The other columns are environment 4892variable names. "File Name" gives the name of the file on a TFTP 4893server, "RAM Address" gives the location in RAM the image will be 4894loaded to, and "Flash Location" gives the image's address in NOR 4895flash or offset in NAND flash. 4896 4897*Note* - these variables don't have to be defined for all boards, some 4898boards currently use other variables for these purposes, and some 4899boards use these variables for other purposes. 4900 4901Image File Name RAM Address Flash Location 4902----- --------- ----------- -------------- 4903u-boot u-boot u-boot_addr_r u-boot_addr 4904Linux kernel bootfile kernel_addr_r kernel_addr 4905device tree blob fdtfile fdt_addr_r fdt_addr 4906ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4907 4908The following environment variables may be used and automatically 4909updated by the network boot commands ("bootp" and "rarpboot"), 4910depending the information provided by your boot server: 4911 4912 bootfile - see above 4913 dnsip - IP address of your Domain Name Server 4914 dnsip2 - IP address of your secondary Domain Name Server 4915 gatewayip - IP address of the Gateway (Router) to use 4916 hostname - Target hostname 4917 ipaddr - see above 4918 netmask - Subnet Mask 4919 rootpath - Pathname of the root filesystem on the NFS server 4920 serverip - see above 4921 4922 4923There are two special Environment Variables: 4924 4925 serial# - contains hardware identification information such 4926 as type string and/or serial number 4927 ethaddr - Ethernet address 4928 4929These variables can be set only once (usually during manufacturing of 4930the board). U-Boot refuses to delete or overwrite these variables 4931once they have been set once. 4932 4933 4934Further special Environment Variables: 4935 4936 ver - Contains the U-Boot version string as printed 4937 with the "version" command. This variable is 4938 readonly (see CONFIG_VERSION_VARIABLE). 4939 4940 4941Please note that changes to some configuration parameters may take 4942only effect after the next boot (yes, that's just like Windoze :-). 4943 4944 4945Callback functions for environment variables: 4946--------------------------------------------- 4947 4948For some environment variables, the behavior of u-boot needs to change 4949when their values are changed. This functionality allows functions to 4950be associated with arbitrary variables. On creation, overwrite, or 4951deletion, the callback will provide the opportunity for some side 4952effect to happen or for the change to be rejected. 4953 4954The callbacks are named and associated with a function using the 4955U_BOOT_ENV_CALLBACK macro in your board or driver code. 4956 4957These callbacks are associated with variables in one of two ways. The 4958static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 4959in the board configuration to a string that defines a list of 4960associations. The list must be in the following format: 4961 4962 entry = variable_name[:callback_name] 4963 list = entry[,list] 4964 4965If the callback name is not specified, then the callback is deleted. 4966Spaces are also allowed anywhere in the list. 4967 4968Callbacks can also be associated by defining the ".callbacks" variable 4969with the same list format above. Any association in ".callbacks" will 4970override any association in the static list. You can define 4971CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 4972".callbacks" environment variable in the default or embedded environment. 4973 4974If CONFIG_REGEX is defined, the variable_name above is evaluated as a 4975regular expression. This allows multiple variables to be connected to 4976the same callback without explicitly listing them all out. 4977 4978 4979Command Line Parsing: 4980===================== 4981 4982There are two different command line parsers available with U-Boot: 4983the old "simple" one, and the much more powerful "hush" shell: 4984 4985Old, simple command line parser: 4986-------------------------------- 4987 4988- supports environment variables (through setenv / saveenv commands) 4989- several commands on one line, separated by ';' 4990- variable substitution using "... ${name} ..." syntax 4991- special characters ('$', ';') can be escaped by prefixing with '\', 4992 for example: 4993 setenv bootcmd bootm \${address} 4994- You can also escape text by enclosing in single apostrophes, for example: 4995 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 4996 4997Hush shell: 4998----------- 4999 5000- similar to Bourne shell, with control structures like 5001 if...then...else...fi, for...do...done; while...do...done, 5002 until...do...done, ... 5003- supports environment ("global") variables (through setenv / saveenv 5004 commands) and local shell variables (through standard shell syntax 5005 "name=value"); only environment variables can be used with "run" 5006 command 5007 5008General rules: 5009-------------- 5010 5011(1) If a command line (or an environment variable executed by a "run" 5012 command) contains several commands separated by semicolon, and 5013 one of these commands fails, then the remaining commands will be 5014 executed anyway. 5015 5016(2) If you execute several variables with one call to run (i. e. 5017 calling run with a list of variables as arguments), any failing 5018 command will cause "run" to terminate, i. e. the remaining 5019 variables are not executed. 5020 5021Note for Redundant Ethernet Interfaces: 5022======================================= 5023 5024Some boards come with redundant Ethernet interfaces; U-Boot supports 5025such configurations and is capable of automatic selection of a 5026"working" interface when needed. MAC assignment works as follows: 5027 5028Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 5029MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 5030"eth1addr" (=>eth1), "eth2addr", ... 5031 5032If the network interface stores some valid MAC address (for instance 5033in SROM), this is used as default address if there is NO correspon- 5034ding setting in the environment; if the corresponding environment 5035variable is set, this overrides the settings in the card; that means: 5036 5037o If the SROM has a valid MAC address, and there is no address in the 5038 environment, the SROM's address is used. 5039 5040o If there is no valid address in the SROM, and a definition in the 5041 environment exists, then the value from the environment variable is 5042 used. 5043 5044o If both the SROM and the environment contain a MAC address, and 5045 both addresses are the same, this MAC address is used. 5046 5047o If both the SROM and the environment contain a MAC address, and the 5048 addresses differ, the value from the environment is used and a 5049 warning is printed. 5050 5051o If neither SROM nor the environment contain a MAC address, an error 5052 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 5053 a random, locally-assigned MAC is used. 5054 5055If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 5056will be programmed into hardware as part of the initialization process. This 5057may be skipped by setting the appropriate 'ethmacskip' environment variable. 5058The naming convention is as follows: 5059"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 5060 5061Image Formats: 5062============== 5063 5064U-Boot is capable of booting (and performing other auxiliary operations on) 5065images in two formats: 5066 5067New uImage format (FIT) 5068----------------------- 5069 5070Flexible and powerful format based on Flattened Image Tree -- FIT (similar 5071to Flattened Device Tree). It allows the use of images with multiple 5072components (several kernels, ramdisks, etc.), with contents protected by 5073SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 5074 5075 5076Old uImage format 5077----------------- 5078 5079Old image format is based on binary files which can be basically anything, 5080preceded by a special header; see the definitions in include/image.h for 5081details; basically, the header defines the following image properties: 5082 5083* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 5084 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 5085 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 5086 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 5087 INTEGRITY). 5088* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86, 5089 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 5090 Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC). 5091* Compression Type (uncompressed, gzip, bzip2) 5092* Load Address 5093* Entry Point 5094* Image Name 5095* Image Timestamp 5096 5097The header is marked by a special Magic Number, and both the header 5098and the data portions of the image are secured against corruption by 5099CRC32 checksums. 5100 5101 5102Linux Support: 5103============== 5104 5105Although U-Boot should support any OS or standalone application 5106easily, the main focus has always been on Linux during the design of 5107U-Boot. 5108 5109U-Boot includes many features that so far have been part of some 5110special "boot loader" code within the Linux kernel. Also, any 5111"initrd" images to be used are no longer part of one big Linux image; 5112instead, kernel and "initrd" are separate images. This implementation 5113serves several purposes: 5114 5115- the same features can be used for other OS or standalone 5116 applications (for instance: using compressed images to reduce the 5117 Flash memory footprint) 5118 5119- it becomes much easier to port new Linux kernel versions because 5120 lots of low-level, hardware dependent stuff are done by U-Boot 5121 5122- the same Linux kernel image can now be used with different "initrd" 5123 images; of course this also means that different kernel images can 5124 be run with the same "initrd". This makes testing easier (you don't 5125 have to build a new "zImage.initrd" Linux image when you just 5126 change a file in your "initrd"). Also, a field-upgrade of the 5127 software is easier now. 5128 5129 5130Linux HOWTO: 5131============ 5132 5133Porting Linux to U-Boot based systems: 5134--------------------------------------- 5135 5136U-Boot cannot save you from doing all the necessary modifications to 5137configure the Linux device drivers for use with your target hardware 5138(no, we don't intend to provide a full virtual machine interface to 5139Linux :-). 5140 5141But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 5142 5143Just make sure your machine specific header file (for instance 5144include/asm-ppc/tqm8xx.h) includes the same definition of the Board 5145Information structure as we define in include/asm-<arch>/u-boot.h, 5146and make sure that your definition of IMAP_ADDR uses the same value 5147as your U-Boot configuration in CONFIG_SYS_IMMR. 5148 5149Note that U-Boot now has a driver model, a unified model for drivers. 5150If you are adding a new driver, plumb it into driver model. If there 5151is no uclass available, you are encouraged to create one. See 5152doc/driver-model. 5153 5154 5155Configuring the Linux kernel: 5156----------------------------- 5157 5158No specific requirements for U-Boot. Make sure you have some root 5159device (initial ramdisk, NFS) for your target system. 5160 5161 5162Building a Linux Image: 5163----------------------- 5164 5165With U-Boot, "normal" build targets like "zImage" or "bzImage" are 5166not used. If you use recent kernel source, a new build target 5167"uImage" will exist which automatically builds an image usable by 5168U-Boot. Most older kernels also have support for a "pImage" target, 5169which was introduced for our predecessor project PPCBoot and uses a 5170100% compatible format. 5171 5172Example: 5173 5174 make TQM850L_defconfig 5175 make oldconfig 5176 make dep 5177 make uImage 5178 5179The "uImage" build target uses a special tool (in 'tools/mkimage') to 5180encapsulate a compressed Linux kernel image with header information, 5181CRC32 checksum etc. for use with U-Boot. This is what we are doing: 5182 5183* build a standard "vmlinux" kernel image (in ELF binary format): 5184 5185* convert the kernel into a raw binary image: 5186 5187 ${CROSS_COMPILE}-objcopy -O binary \ 5188 -R .note -R .comment \ 5189 -S vmlinux linux.bin 5190 5191* compress the binary image: 5192 5193 gzip -9 linux.bin 5194 5195* package compressed binary image for U-Boot: 5196 5197 mkimage -A ppc -O linux -T kernel -C gzip \ 5198 -a 0 -e 0 -n "Linux Kernel Image" \ 5199 -d linux.bin.gz uImage 5200 5201 5202The "mkimage" tool can also be used to create ramdisk images for use 5203with U-Boot, either separated from the Linux kernel image, or 5204combined into one file. "mkimage" encapsulates the images with a 64 5205byte header containing information about target architecture, 5206operating system, image type, compression method, entry points, time 5207stamp, CRC32 checksums, etc. 5208 5209"mkimage" can be called in two ways: to verify existing images and 5210print the header information, or to build new images. 5211 5212In the first form (with "-l" option) mkimage lists the information 5213contained in the header of an existing U-Boot image; this includes 5214checksum verification: 5215 5216 tools/mkimage -l image 5217 -l ==> list image header information 5218 5219The second form (with "-d" option) is used to build a U-Boot image 5220from a "data file" which is used as image payload: 5221 5222 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 5223 -n name -d data_file image 5224 -A ==> set architecture to 'arch' 5225 -O ==> set operating system to 'os' 5226 -T ==> set image type to 'type' 5227 -C ==> set compression type 'comp' 5228 -a ==> set load address to 'addr' (hex) 5229 -e ==> set entry point to 'ep' (hex) 5230 -n ==> set image name to 'name' 5231 -d ==> use image data from 'datafile' 5232 5233Right now, all Linux kernels for PowerPC systems use the same load 5234address (0x00000000), but the entry point address depends on the 5235kernel version: 5236 5237- 2.2.x kernels have the entry point at 0x0000000C, 5238- 2.3.x and later kernels have the entry point at 0x00000000. 5239 5240So a typical call to build a U-Boot image would read: 5241 5242 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5243 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 5244 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 5245 > examples/uImage.TQM850L 5246 Image Name: 2.4.4 kernel for TQM850L 5247 Created: Wed Jul 19 02:34:59 2000 5248 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5249 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5250 Load Address: 0x00000000 5251 Entry Point: 0x00000000 5252 5253To verify the contents of the image (or check for corruption): 5254 5255 -> tools/mkimage -l examples/uImage.TQM850L 5256 Image Name: 2.4.4 kernel for TQM850L 5257 Created: Wed Jul 19 02:34:59 2000 5258 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5259 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 5260 Load Address: 0x00000000 5261 Entry Point: 0x00000000 5262 5263NOTE: for embedded systems where boot time is critical you can trade 5264speed for memory and install an UNCOMPRESSED image instead: this 5265needs more space in Flash, but boots much faster since it does not 5266need to be uncompressed: 5267 5268 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 5269 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 5270 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 5271 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 5272 > examples/uImage.TQM850L-uncompressed 5273 Image Name: 2.4.4 kernel for TQM850L 5274 Created: Wed Jul 19 02:34:59 2000 5275 Image Type: PowerPC Linux Kernel Image (uncompressed) 5276 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 5277 Load Address: 0x00000000 5278 Entry Point: 0x00000000 5279 5280 5281Similar you can build U-Boot images from a 'ramdisk.image.gz' file 5282when your kernel is intended to use an initial ramdisk: 5283 5284 -> tools/mkimage -n 'Simple Ramdisk Image' \ 5285 > -A ppc -O linux -T ramdisk -C gzip \ 5286 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 5287 Image Name: Simple Ramdisk Image 5288 Created: Wed Jan 12 14:01:50 2000 5289 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5290 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 5291 Load Address: 0x00000000 5292 Entry Point: 0x00000000 5293 5294The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 5295option performs the converse operation of the mkimage's second form (the "-d" 5296option). Given an image built by mkimage, the dumpimage extracts a "data file" 5297from the image: 5298 5299 tools/dumpimage -i image -T type -p position data_file 5300 -i ==> extract from the 'image' a specific 'data_file' 5301 -T ==> set image type to 'type' 5302 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 5303 5304 5305Installing a Linux Image: 5306------------------------- 5307 5308To downloading a U-Boot image over the serial (console) interface, 5309you must convert the image to S-Record format: 5310 5311 objcopy -I binary -O srec examples/image examples/image.srec 5312 5313The 'objcopy' does not understand the information in the U-Boot 5314image header, so the resulting S-Record file will be relative to 5315address 0x00000000. To load it to a given address, you need to 5316specify the target address as 'offset' parameter with the 'loads' 5317command. 5318 5319Example: install the image to address 0x40100000 (which on the 5320TQM8xxL is in the first Flash bank): 5321 5322 => erase 40100000 401FFFFF 5323 5324 .......... done 5325 Erased 8 sectors 5326 5327 => loads 40100000 5328 ## Ready for S-Record download ... 5329 ~>examples/image.srec 5330 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 5331 ... 5332 15989 15990 15991 15992 5333 [file transfer complete] 5334 [connected] 5335 ## Start Addr = 0x00000000 5336 5337 5338You can check the success of the download using the 'iminfo' command; 5339this includes a checksum verification so you can be sure no data 5340corruption happened: 5341 5342 => imi 40100000 5343 5344 ## Checking Image at 40100000 ... 5345 Image Name: 2.2.13 for initrd on TQM850L 5346 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5347 Data Size: 335725 Bytes = 327 kB = 0 MB 5348 Load Address: 00000000 5349 Entry Point: 0000000c 5350 Verifying Checksum ... OK 5351 5352 5353Boot Linux: 5354----------- 5355 5356The "bootm" command is used to boot an application that is stored in 5357memory (RAM or Flash). In case of a Linux kernel image, the contents 5358of the "bootargs" environment variable is passed to the kernel as 5359parameters. You can check and modify this variable using the 5360"printenv" and "setenv" commands: 5361 5362 5363 => printenv bootargs 5364 bootargs=root=/dev/ram 5365 5366 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5367 5368 => printenv bootargs 5369 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5370 5371 => bootm 40020000 5372 ## Booting Linux kernel at 40020000 ... 5373 Image Name: 2.2.13 for NFS on TQM850L 5374 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5375 Data Size: 381681 Bytes = 372 kB = 0 MB 5376 Load Address: 00000000 5377 Entry Point: 0000000c 5378 Verifying Checksum ... OK 5379 Uncompressing Kernel Image ... OK 5380 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 5381 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 5382 time_init: decrementer frequency = 187500000/60 5383 Calibrating delay loop... 49.77 BogoMIPS 5384 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 5385 ... 5386 5387If you want to boot a Linux kernel with initial RAM disk, you pass 5388the memory addresses of both the kernel and the initrd image (PPBCOOT 5389format!) to the "bootm" command: 5390 5391 => imi 40100000 40200000 5392 5393 ## Checking Image at 40100000 ... 5394 Image Name: 2.2.13 for initrd on TQM850L 5395 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5396 Data Size: 335725 Bytes = 327 kB = 0 MB 5397 Load Address: 00000000 5398 Entry Point: 0000000c 5399 Verifying Checksum ... OK 5400 5401 ## Checking Image at 40200000 ... 5402 Image Name: Simple Ramdisk Image 5403 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5404 Data Size: 566530 Bytes = 553 kB = 0 MB 5405 Load Address: 00000000 5406 Entry Point: 00000000 5407 Verifying Checksum ... OK 5408 5409 => bootm 40100000 40200000 5410 ## Booting Linux kernel at 40100000 ... 5411 Image Name: 2.2.13 for initrd on TQM850L 5412 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5413 Data Size: 335725 Bytes = 327 kB = 0 MB 5414 Load Address: 00000000 5415 Entry Point: 0000000c 5416 Verifying Checksum ... OK 5417 Uncompressing Kernel Image ... OK 5418 ## Loading RAMDisk Image at 40200000 ... 5419 Image Name: Simple Ramdisk Image 5420 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 5421 Data Size: 566530 Bytes = 553 kB = 0 MB 5422 Load Address: 00000000 5423 Entry Point: 00000000 5424 Verifying Checksum ... OK 5425 Loading Ramdisk ... OK 5426 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 5427 Boot arguments: root=/dev/ram 5428 time_init: decrementer frequency = 187500000/60 5429 Calibrating delay loop... 49.77 BogoMIPS 5430 ... 5431 RAMDISK: Compressed image found at block 0 5432 VFS: Mounted root (ext2 filesystem). 5433 5434 bash# 5435 5436Boot Linux and pass a flat device tree: 5437----------- 5438 5439First, U-Boot must be compiled with the appropriate defines. See the section 5440titled "Linux Kernel Interface" above for a more in depth explanation. The 5441following is an example of how to start a kernel and pass an updated 5442flat device tree: 5443 5444=> print oftaddr 5445oftaddr=0x300000 5446=> print oft 5447oft=oftrees/mpc8540ads.dtb 5448=> tftp $oftaddr $oft 5449Speed: 1000, full duplex 5450Using TSEC0 device 5451TFTP from server 192.168.1.1; our IP address is 192.168.1.101 5452Filename 'oftrees/mpc8540ads.dtb'. 5453Load address: 0x300000 5454Loading: # 5455done 5456Bytes transferred = 4106 (100a hex) 5457=> tftp $loadaddr $bootfile 5458Speed: 1000, full duplex 5459Using TSEC0 device 5460TFTP from server 192.168.1.1; our IP address is 192.168.1.2 5461Filename 'uImage'. 5462Load address: 0x200000 5463Loading:############ 5464done 5465Bytes transferred = 1029407 (fb51f hex) 5466=> print loadaddr 5467loadaddr=200000 5468=> print oftaddr 5469oftaddr=0x300000 5470=> bootm $loadaddr - $oftaddr 5471## Booting image at 00200000 ... 5472 Image Name: Linux-2.6.17-dirty 5473 Image Type: PowerPC Linux Kernel Image (gzip compressed) 5474 Data Size: 1029343 Bytes = 1005.2 kB 5475 Load Address: 00000000 5476 Entry Point: 00000000 5477 Verifying Checksum ... OK 5478 Uncompressing Kernel Image ... OK 5479Booting using flat device tree at 0x300000 5480Using MPC85xx ADS machine description 5481Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 5482[snip] 5483 5484 5485More About U-Boot Image Types: 5486------------------------------ 5487 5488U-Boot supports the following image types: 5489 5490 "Standalone Programs" are directly runnable in the environment 5491 provided by U-Boot; it is expected that (if they behave 5492 well) you can continue to work in U-Boot after return from 5493 the Standalone Program. 5494 "OS Kernel Images" are usually images of some Embedded OS which 5495 will take over control completely. Usually these programs 5496 will install their own set of exception handlers, device 5497 drivers, set up the MMU, etc. - this means, that you cannot 5498 expect to re-enter U-Boot except by resetting the CPU. 5499 "RAMDisk Images" are more or less just data blocks, and their 5500 parameters (address, size) are passed to an OS kernel that is 5501 being started. 5502 "Multi-File Images" contain several images, typically an OS 5503 (Linux) kernel image and one or more data images like 5504 RAMDisks. This construct is useful for instance when you want 5505 to boot over the network using BOOTP etc., where the boot 5506 server provides just a single image file, but you want to get 5507 for instance an OS kernel and a RAMDisk image. 5508 5509 "Multi-File Images" start with a list of image sizes, each 5510 image size (in bytes) specified by an "uint32_t" in network 5511 byte order. This list is terminated by an "(uint32_t)0". 5512 Immediately after the terminating 0 follow the images, one by 5513 one, all aligned on "uint32_t" boundaries (size rounded up to 5514 a multiple of 4 bytes). 5515 5516 "Firmware Images" are binary images containing firmware (like 5517 U-Boot or FPGA images) which usually will be programmed to 5518 flash memory. 5519 5520 "Script files" are command sequences that will be executed by 5521 U-Boot's command interpreter; this feature is especially 5522 useful when you configure U-Boot to use a real shell (hush) 5523 as command interpreter. 5524 5525Booting the Linux zImage: 5526------------------------- 5527 5528On some platforms, it's possible to boot Linux zImage. This is done 5529using the "bootz" command. The syntax of "bootz" command is the same 5530as the syntax of "bootm" command. 5531 5532Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 5533kernel with raw initrd images. The syntax is slightly different, the 5534address of the initrd must be augmented by it's size, in the following 5535format: "<initrd addres>:<initrd size>". 5536 5537 5538Standalone HOWTO: 5539================= 5540 5541One of the features of U-Boot is that you can dynamically load and 5542run "standalone" applications, which can use some resources of 5543U-Boot like console I/O functions or interrupt services. 5544 5545Two simple examples are included with the sources: 5546 5547"Hello World" Demo: 5548------------------- 5549 5550'examples/hello_world.c' contains a small "Hello World" Demo 5551application; it is automatically compiled when you build U-Boot. 5552It's configured to run at address 0x00040004, so you can play with it 5553like that: 5554 5555 => loads 5556 ## Ready for S-Record download ... 5557 ~>examples/hello_world.srec 5558 1 2 3 4 5 6 7 8 9 10 11 ... 5559 [file transfer complete] 5560 [connected] 5561 ## Start Addr = 0x00040004 5562 5563 => go 40004 Hello World! This is a test. 5564 ## Starting application at 0x00040004 ... 5565 Hello World 5566 argc = 7 5567 argv[0] = "40004" 5568 argv[1] = "Hello" 5569 argv[2] = "World!" 5570 argv[3] = "This" 5571 argv[4] = "is" 5572 argv[5] = "a" 5573 argv[6] = "test." 5574 argv[7] = "<NULL>" 5575 Hit any key to exit ... 5576 5577 ## Application terminated, rc = 0x0 5578 5579Another example, which demonstrates how to register a CPM interrupt 5580handler with the U-Boot code, can be found in 'examples/timer.c'. 5581Here, a CPM timer is set up to generate an interrupt every second. 5582The interrupt service routine is trivial, just printing a '.' 5583character, but this is just a demo program. The application can be 5584controlled by the following keys: 5585 5586 ? - print current values og the CPM Timer registers 5587 b - enable interrupts and start timer 5588 e - stop timer and disable interrupts 5589 q - quit application 5590 5591 => loads 5592 ## Ready for S-Record download ... 5593 ~>examples/timer.srec 5594 1 2 3 4 5 6 7 8 9 10 11 ... 5595 [file transfer complete] 5596 [connected] 5597 ## Start Addr = 0x00040004 5598 5599 => go 40004 5600 ## Starting application at 0x00040004 ... 5601 TIMERS=0xfff00980 5602 Using timer 1 5603 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 5604 5605Hit 'b': 5606 [q, b, e, ?] Set interval 1000000 us 5607 Enabling timer 5608Hit '?': 5609 [q, b, e, ?] ........ 5610 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 5611Hit '?': 5612 [q, b, e, ?] . 5613 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 5614Hit '?': 5615 [q, b, e, ?] . 5616 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 5617Hit '?': 5618 [q, b, e, ?] . 5619 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 5620Hit 'e': 5621 [q, b, e, ?] ...Stopping timer 5622Hit 'q': 5623 [q, b, e, ?] ## Application terminated, rc = 0x0 5624 5625 5626Minicom warning: 5627================ 5628 5629Over time, many people have reported problems when trying to use the 5630"minicom" terminal emulation program for serial download. I (wd) 5631consider minicom to be broken, and recommend not to use it. Under 5632Unix, I recommend to use C-Kermit for general purpose use (and 5633especially for kermit binary protocol download ("loadb" command), and 5634use "cu" for S-Record download ("loads" command). See 5635http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 5636for help with kermit. 5637 5638 5639Nevertheless, if you absolutely want to use it try adding this 5640configuration to your "File transfer protocols" section: 5641 5642 Name Program Name U/D FullScr IO-Red. Multi 5643 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 5644 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 5645 5646 5647NetBSD Notes: 5648============= 5649 5650Starting at version 0.9.2, U-Boot supports NetBSD both as host 5651(build U-Boot) and target system (boots NetBSD/mpc8xx). 5652 5653Building requires a cross environment; it is known to work on 5654NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 5655need gmake since the Makefiles are not compatible with BSD make). 5656Note that the cross-powerpc package does not install include files; 5657attempting to build U-Boot will fail because <machine/ansi.h> is 5658missing. This file has to be installed and patched manually: 5659 5660 # cd /usr/pkg/cross/powerpc-netbsd/include 5661 # mkdir powerpc 5662 # ln -s powerpc machine 5663 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 5664 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 5665 5666Native builds *don't* work due to incompatibilities between native 5667and U-Boot include files. 5668 5669Booting assumes that (the first part of) the image booted is a 5670stage-2 loader which in turn loads and then invokes the kernel 5671proper. Loader sources will eventually appear in the NetBSD source 5672tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 5673meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 5674 5675 5676Implementation Internals: 5677========================= 5678 5679The following is not intended to be a complete description of every 5680implementation detail. However, it should help to understand the 5681inner workings of U-Boot and make it easier to port it to custom 5682hardware. 5683 5684 5685Initial Stack, Global Data: 5686--------------------------- 5687 5688The implementation of U-Boot is complicated by the fact that U-Boot 5689starts running out of ROM (flash memory), usually without access to 5690system RAM (because the memory controller is not initialized yet). 5691This means that we don't have writable Data or BSS segments, and BSS 5692is not initialized as zero. To be able to get a C environment working 5693at all, we have to allocate at least a minimal stack. Implementation 5694options for this are defined and restricted by the CPU used: Some CPU 5695models provide on-chip memory (like the IMMR area on MPC8xx and 5696MPC826x processors), on others (parts of) the data cache can be 5697locked as (mis-) used as memory, etc. 5698 5699 Chris Hallinan posted a good summary of these issues to the 5700 U-Boot mailing list: 5701 5702 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 5703 From: "Chris Hallinan" <clh@net1plus.com> 5704 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 5705 ... 5706 5707 Correct me if I'm wrong, folks, but the way I understand it 5708 is this: Using DCACHE as initial RAM for Stack, etc, does not 5709 require any physical RAM backing up the cache. The cleverness 5710 is that the cache is being used as a temporary supply of 5711 necessary storage before the SDRAM controller is setup. It's 5712 beyond the scope of this list to explain the details, but you 5713 can see how this works by studying the cache architecture and 5714 operation in the architecture and processor-specific manuals. 5715 5716 OCM is On Chip Memory, which I believe the 405GP has 4K. It 5717 is another option for the system designer to use as an 5718 initial stack/RAM area prior to SDRAM being available. Either 5719 option should work for you. Using CS 4 should be fine if your 5720 board designers haven't used it for something that would 5721 cause you grief during the initial boot! It is frequently not 5722 used. 5723 5724 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 5725 with your processor/board/system design. The default value 5726 you will find in any recent u-boot distribution in 5727 walnut.h should work for you. I'd set it to a value larger 5728 than your SDRAM module. If you have a 64MB SDRAM module, set 5729 it above 400_0000. Just make sure your board has no resources 5730 that are supposed to respond to that address! That code in 5731 start.S has been around a while and should work as is when 5732 you get the config right. 5733 5734 -Chris Hallinan 5735 DS4.COM, Inc. 5736 5737It is essential to remember this, since it has some impact on the C 5738code for the initialization procedures: 5739 5740* Initialized global data (data segment) is read-only. Do not attempt 5741 to write it. 5742 5743* Do not use any uninitialized global data (or implicitly initialized 5744 as zero data - BSS segment) at all - this is undefined, initiali- 5745 zation is performed later (when relocating to RAM). 5746 5747* Stack space is very limited. Avoid big data buffers or things like 5748 that. 5749 5750Having only the stack as writable memory limits means we cannot use 5751normal global data to share information between the code. But it 5752turned out that the implementation of U-Boot can be greatly 5753simplified by making a global data structure (gd_t) available to all 5754functions. We could pass a pointer to this data as argument to _all_ 5755functions, but this would bloat the code. Instead we use a feature of 5756the GCC compiler (Global Register Variables) to share the data: we 5757place a pointer (gd) to the global data into a register which we 5758reserve for this purpose. 5759 5760When choosing a register for such a purpose we are restricted by the 5761relevant (E)ABI specifications for the current architecture, and by 5762GCC's implementation. 5763 5764For PowerPC, the following registers have specific use: 5765 R1: stack pointer 5766 R2: reserved for system use 5767 R3-R4: parameter passing and return values 5768 R5-R10: parameter passing 5769 R13: small data area pointer 5770 R30: GOT pointer 5771 R31: frame pointer 5772 5773 (U-Boot also uses R12 as internal GOT pointer. r12 5774 is a volatile register so r12 needs to be reset when 5775 going back and forth between asm and C) 5776 5777 ==> U-Boot will use R2 to hold a pointer to the global data 5778 5779 Note: on PPC, we could use a static initializer (since the 5780 address of the global data structure is known at compile time), 5781 but it turned out that reserving a register results in somewhat 5782 smaller code - although the code savings are not that big (on 5783 average for all boards 752 bytes for the whole U-Boot image, 5784 624 text + 127 data). 5785 5786On ARM, the following registers are used: 5787 5788 R0: function argument word/integer result 5789 R1-R3: function argument word 5790 R9: platform specific 5791 R10: stack limit (used only if stack checking is enabled) 5792 R11: argument (frame) pointer 5793 R12: temporary workspace 5794 R13: stack pointer 5795 R14: link register 5796 R15: program counter 5797 5798 ==> U-Boot will use R9 to hold a pointer to the global data 5799 5800 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 5801 5802On Nios II, the ABI is documented here: 5803 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 5804 5805 ==> U-Boot will use gp to hold a pointer to the global data 5806 5807 Note: on Nios II, we give "-G0" option to gcc and don't use gp 5808 to access small data sections, so gp is free. 5809 5810On NDS32, the following registers are used: 5811 5812 R0-R1: argument/return 5813 R2-R5: argument 5814 R15: temporary register for assembler 5815 R16: trampoline register 5816 R28: frame pointer (FP) 5817 R29: global pointer (GP) 5818 R30: link register (LP) 5819 R31: stack pointer (SP) 5820 PC: program counter (PC) 5821 5822 ==> U-Boot will use R10 to hold a pointer to the global data 5823 5824NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 5825or current versions of GCC may "optimize" the code too much. 5826 5827Memory Management: 5828------------------ 5829 5830U-Boot runs in system state and uses physical addresses, i.e. the 5831MMU is not used either for address mapping nor for memory protection. 5832 5833The available memory is mapped to fixed addresses using the memory 5834controller. In this process, a contiguous block is formed for each 5835memory type (Flash, SDRAM, SRAM), even when it consists of several 5836physical memory banks. 5837 5838U-Boot is installed in the first 128 kB of the first Flash bank (on 5839TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 5840booting and sizing and initializing DRAM, the code relocates itself 5841to the upper end of DRAM. Immediately below the U-Boot code some 5842memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 5843configuration setting]. Below that, a structure with global Board 5844Info data is placed, followed by the stack (growing downward). 5845 5846Additionally, some exception handler code is copied to the low 8 kB 5847of DRAM (0x00000000 ... 0x00001FFF). 5848 5849So a typical memory configuration with 16 MB of DRAM could look like 5850this: 5851 5852 0x0000 0000 Exception Vector code 5853 : 5854 0x0000 1FFF 5855 0x0000 2000 Free for Application Use 5856 : 5857 : 5858 5859 : 5860 : 5861 0x00FB FF20 Monitor Stack (Growing downward) 5862 0x00FB FFAC Board Info Data and permanent copy of global data 5863 0x00FC 0000 Malloc Arena 5864 : 5865 0x00FD FFFF 5866 0x00FE 0000 RAM Copy of Monitor Code 5867 ... eventually: LCD or video framebuffer 5868 ... eventually: pRAM (Protected RAM - unchanged by reset) 5869 0x00FF FFFF [End of RAM] 5870 5871 5872System Initialization: 5873---------------------- 5874 5875In the reset configuration, U-Boot starts at the reset entry point 5876(on most PowerPC systems at address 0x00000100). Because of the reset 5877configuration for CS0# this is a mirror of the on board Flash memory. 5878To be able to re-map memory U-Boot then jumps to its link address. 5879To be able to implement the initialization code in C, a (small!) 5880initial stack is set up in the internal Dual Ported RAM (in case CPUs 5881which provide such a feature like MPC8xx or MPC8260), or in a locked 5882part of the data cache. After that, U-Boot initializes the CPU core, 5883the caches and the SIU. 5884 5885Next, all (potentially) available memory banks are mapped using a 5886preliminary mapping. For example, we put them on 512 MB boundaries 5887(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5888on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5889programmed for SDRAM access. Using the temporary configuration, a 5890simple memory test is run that determines the size of the SDRAM 5891banks. 5892 5893When there is more than one SDRAM bank, and the banks are of 5894different size, the largest is mapped first. For equal size, the first 5895bank (CS2#) is mapped first. The first mapping is always for address 58960x00000000, with any additional banks following immediately to create 5897contiguous memory starting from 0. 5898 5899Then, the monitor installs itself at the upper end of the SDRAM area 5900and allocates memory for use by malloc() and for the global Board 5901Info data; also, the exception vector code is copied to the low RAM 5902pages, and the final stack is set up. 5903 5904Only after this relocation will you have a "normal" C environment; 5905until that you are restricted in several ways, mostly because you are 5906running from ROM, and because the code will have to be relocated to a 5907new address in RAM. 5908 5909 5910U-Boot Porting Guide: 5911---------------------- 5912 5913[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 5914list, October 2002] 5915 5916 5917int main(int argc, char *argv[]) 5918{ 5919 sighandler_t no_more_time; 5920 5921 signal(SIGALRM, no_more_time); 5922 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 5923 5924 if (available_money > available_manpower) { 5925 Pay consultant to port U-Boot; 5926 return 0; 5927 } 5928 5929 Download latest U-Boot source; 5930 5931 Subscribe to u-boot mailing list; 5932 5933 if (clueless) 5934 email("Hi, I am new to U-Boot, how do I get started?"); 5935 5936 while (learning) { 5937 Read the README file in the top level directory; 5938 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5939 Read applicable doc/*.README; 5940 Read the source, Luke; 5941 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5942 } 5943 5944 if (available_money > toLocalCurrency ($2500)) 5945 Buy a BDI3000; 5946 else 5947 Add a lot of aggravation and time; 5948 5949 if (a similar board exists) { /* hopefully... */ 5950 cp -a board/<similar> board/<myboard> 5951 cp include/configs/<similar>.h include/configs/<myboard>.h 5952 } else { 5953 Create your own board support subdirectory; 5954 Create your own board include/configs/<myboard>.h file; 5955 } 5956 Edit new board/<myboard> files 5957 Edit new include/configs/<myboard>.h 5958 5959 while (!accepted) { 5960 while (!running) { 5961 do { 5962 Add / modify source code; 5963 } until (compiles); 5964 Debug; 5965 if (clueless) 5966 email("Hi, I am having problems..."); 5967 } 5968 Send patch file to the U-Boot email list; 5969 if (reasonable critiques) 5970 Incorporate improvements from email list code review; 5971 else 5972 Defend code as written; 5973 } 5974 5975 return 0; 5976} 5977 5978void no_more_time (int sig) 5979{ 5980 hire_a_guru(); 5981} 5982 5983 5984Coding Standards: 5985----------------- 5986 5987All contributions to U-Boot should conform to the Linux kernel 5988coding style; see the file "Documentation/CodingStyle" and the script 5989"scripts/Lindent" in your Linux kernel source directory. 5990 5991Source files originating from a different project (for example the 5992MTD subsystem) are generally exempt from these guidelines and are not 5993reformatted to ease subsequent migration to newer versions of those 5994sources. 5995 5996Please note that U-Boot is implemented in C (and to some small parts in 5997Assembler); no C++ is used, so please do not use C++ style comments (//) 5998in your code. 5999 6000Please also stick to the following formatting rules: 6001- remove any trailing white space 6002- use TAB characters for indentation and vertical alignment, not spaces 6003- make sure NOT to use DOS '\r\n' line feeds 6004- do not add more than 2 consecutive empty lines to source files 6005- do not add trailing empty lines to source files 6006 6007Submissions which do not conform to the standards may be returned 6008with a request to reformat the changes. 6009 6010 6011Submitting Patches: 6012------------------- 6013 6014Since the number of patches for U-Boot is growing, we need to 6015establish some rules. Submissions which do not conform to these rules 6016may be rejected, even when they contain important and valuable stuff. 6017 6018Please see http://www.denx.de/wiki/U-Boot/Patches for details. 6019 6020Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 6021see http://lists.denx.de/mailman/listinfo/u-boot 6022 6023When you send a patch, please include the following information with 6024it: 6025 6026* For bug fixes: a description of the bug and how your patch fixes 6027 this bug. Please try to include a way of demonstrating that the 6028 patch actually fixes something. 6029 6030* For new features: a description of the feature and your 6031 implementation. 6032 6033* A CHANGELOG entry as plaintext (separate from the patch) 6034 6035* For major contributions, add a MAINTAINERS file with your 6036 information and associated file and directory references. 6037 6038* When you add support for a new board, don't forget to add a 6039 maintainer e-mail address to the boards.cfg file, too. 6040 6041* If your patch adds new configuration options, don't forget to 6042 document these in the README file. 6043 6044* The patch itself. If you are using git (which is *strongly* 6045 recommended) you can easily generate the patch using the 6046 "git format-patch". If you then use "git send-email" to send it to 6047 the U-Boot mailing list, you will avoid most of the common problems 6048 with some other mail clients. 6049 6050 If you cannot use git, use "diff -purN OLD NEW". If your version of 6051 diff does not support these options, then get the latest version of 6052 GNU diff. 6053 6054 The current directory when running this command shall be the parent 6055 directory of the U-Boot source tree (i. e. please make sure that 6056 your patch includes sufficient directory information for the 6057 affected files). 6058 6059 We prefer patches as plain text. MIME attachments are discouraged, 6060 and compressed attachments must not be used. 6061 6062* If one logical set of modifications affects or creates several 6063 files, all these changes shall be submitted in a SINGLE patch file. 6064 6065* Changesets that contain different, unrelated modifications shall be 6066 submitted as SEPARATE patches, one patch per changeset. 6067 6068 6069Notes: 6070 6071* Before sending the patch, run the buildman script on your patched 6072 source tree and make sure that no errors or warnings are reported 6073 for any of the boards. 6074 6075* Keep your modifications to the necessary minimum: A patch 6076 containing several unrelated changes or arbitrary reformats will be 6077 returned with a request to re-formatting / split it. 6078 6079* If you modify existing code, make sure that your new code does not 6080 add to the memory footprint of the code ;-) Small is beautiful! 6081 When adding new features, these should compile conditionally only 6082 (using #ifdef), and the resulting code with the new feature 6083 disabled must not need more memory than the old code without your 6084 modification. 6085 6086* Remember that there is a size limit of 100 kB per message on the 6087 u-boot mailing list. Bigger patches will be moderated. If they are 6088 reasonable and not too big, they will be acknowledged. But patches 6089 bigger than the size limit should be avoided. 6090