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 /m68k Files generic to m68k architecture 140 /microblaze Files generic to microblaze architecture 141 /mips Files generic to MIPS architecture 142 /nds32 Files generic to NDS32 architecture 143 /nios2 Files generic to Altera NIOS2 architecture 144 /openrisc Files generic to OpenRISC architecture 145 /powerpc Files generic to PowerPC architecture 146 /riscv Files generic to RISC-V 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- ARM Platform Bus Type(CCI): 317 CoreLink Cache Coherent Interconnect (CCI) is ARM BUS which 318 provides full cache coherency between two clusters of multi-core 319 CPUs and I/O coherency for devices and I/O masters 320 321 CONFIG_SYS_FSL_HAS_CCI400 322 323 Defined For SoC that has cache coherent interconnect 324 CCN-400 325 326 CONFIG_SYS_FSL_HAS_CCN504 327 328 Defined for SoC that has cache coherent interconnect CCN-504 329 330The following options need to be configured: 331 332- CPU Type: Define exactly one, e.g. CONFIG_MPC85XX. 333 334- Board Type: Define exactly one, e.g. CONFIG_MPC8540ADS. 335 336- Marvell Family Member 337 CONFIG_SYS_MVFS - define it if you want to enable 338 multiple fs option at one time 339 for marvell soc family 340 341- 85xx CPU Options: 342 CONFIG_SYS_PPC64 343 344 Specifies that the core is a 64-bit PowerPC implementation (implements 345 the "64" category of the Power ISA). This is necessary for ePAPR 346 compliance, among other possible reasons. 347 348 CONFIG_SYS_FSL_TBCLK_DIV 349 350 Defines the core time base clock divider ratio compared to the 351 system clock. On most PQ3 devices this is 8, on newer QorIQ 352 devices it can be 16 or 32. The ratio varies from SoC to Soc. 353 354 CONFIG_SYS_FSL_PCIE_COMPAT 355 356 Defines the string to utilize when trying to match PCIe device 357 tree nodes for the given platform. 358 359 CONFIG_SYS_FSL_ERRATUM_A004510 360 361 Enables a workaround for erratum A004510. If set, 362 then CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV and 363 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY must be set. 364 365 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV 366 CONFIG_SYS_FSL_ERRATUM_A004510_SVR_REV2 (optional) 367 368 Defines one or two SoC revisions (low 8 bits of SVR) 369 for which the A004510 workaround should be applied. 370 371 The rest of SVR is either not relevant to the decision 372 of whether the erratum is present (e.g. p2040 versus 373 p2041) or is implied by the build target, which controls 374 whether CONFIG_SYS_FSL_ERRATUM_A004510 is set. 375 376 See Freescale App Note 4493 for more information about 377 this erratum. 378 379 CONFIG_A003399_NOR_WORKAROUND 380 Enables a workaround for IFC erratum A003399. It is only 381 required during NOR boot. 382 383 CONFIG_A008044_WORKAROUND 384 Enables a workaround for T1040/T1042 erratum A008044. It is only 385 required during NAND boot and valid for Rev 1.0 SoC revision 386 387 CONFIG_SYS_FSL_CORENET_SNOOPVEC_COREONLY 388 389 This is the value to write into CCSR offset 0x18600 390 according to the A004510 workaround. 391 392 CONFIG_SYS_FSL_DSP_DDR_ADDR 393 This value denotes start offset of DDR memory which is 394 connected exclusively to the DSP cores. 395 396 CONFIG_SYS_FSL_DSP_M2_RAM_ADDR 397 This value denotes start offset of M2 memory 398 which is directly connected to the DSP core. 399 400 CONFIG_SYS_FSL_DSP_M3_RAM_ADDR 401 This value denotes start offset of M3 memory which is directly 402 connected to the DSP core. 403 404 CONFIG_SYS_FSL_DSP_CCSRBAR_DEFAULT 405 This value denotes start offset of DSP CCSR space. 406 407 CONFIG_SYS_FSL_SINGLE_SOURCE_CLK 408 Single Source Clock is clocking mode present in some of FSL SoC's. 409 In this mode, a single differential clock is used to supply 410 clocks to the sysclock, ddrclock and usbclock. 411 412 CONFIG_SYS_CPC_REINIT_F 413 This CONFIG is defined when the CPC is configured as SRAM at the 414 time of U-Boot entry and is required to be re-initialized. 415 416 CONFIG_DEEP_SLEEP 417 Indicates this SoC supports deep sleep feature. If deep sleep is 418 supported, core will start to execute uboot when wakes up. 419 420- Generic CPU options: 421 CONFIG_SYS_BIG_ENDIAN, CONFIG_SYS_LITTLE_ENDIAN 422 423 Defines the endianess of the CPU. Implementation of those 424 values is arch specific. 425 426 CONFIG_SYS_FSL_DDR 427 Freescale DDR driver in use. This type of DDR controller is 428 found in mpc83xx, mpc85xx, mpc86xx as well as some ARM core 429 SoCs. 430 431 CONFIG_SYS_FSL_DDR_ADDR 432 Freescale DDR memory-mapped register base. 433 434 CONFIG_SYS_FSL_DDR_EMU 435 Specify emulator support for DDR. Some DDR features such as 436 deskew training are not available. 437 438 CONFIG_SYS_FSL_DDRC_GEN1 439 Freescale DDR1 controller. 440 441 CONFIG_SYS_FSL_DDRC_GEN2 442 Freescale DDR2 controller. 443 444 CONFIG_SYS_FSL_DDRC_GEN3 445 Freescale DDR3 controller. 446 447 CONFIG_SYS_FSL_DDRC_GEN4 448 Freescale DDR4 controller. 449 450 CONFIG_SYS_FSL_DDRC_ARM_GEN3 451 Freescale DDR3 controller for ARM-based SoCs. 452 453 CONFIG_SYS_FSL_DDR1 454 Board config to use DDR1. It can be enabled for SoCs with 455 Freescale DDR1 or DDR2 controllers, depending on the board 456 implemetation. 457 458 CONFIG_SYS_FSL_DDR2 459 Board config to use DDR2. It can be enabled for SoCs with 460 Freescale DDR2 or DDR3 controllers, depending on the board 461 implementation. 462 463 CONFIG_SYS_FSL_DDR3 464 Board config to use DDR3. It can be enabled for SoCs with 465 Freescale DDR3 or DDR3L controllers. 466 467 CONFIG_SYS_FSL_DDR3L 468 Board config to use DDR3L. It can be enabled for SoCs with 469 DDR3L controllers. 470 471 CONFIG_SYS_FSL_DDR4 472 Board config to use DDR4. It can be enabled for SoCs with 473 DDR4 controllers. 474 475 CONFIG_SYS_FSL_IFC_BE 476 Defines the IFC controller register space as Big Endian 477 478 CONFIG_SYS_FSL_IFC_LE 479 Defines the IFC controller register space as Little Endian 480 481 CONFIG_SYS_FSL_IFC_CLK_DIV 482 Defines divider of platform clock(clock input to IFC controller). 483 484 CONFIG_SYS_FSL_LBC_CLK_DIV 485 Defines divider of platform clock(clock input to eLBC controller). 486 487 CONFIG_SYS_FSL_PBL_PBI 488 It enables addition of RCW (Power on reset configuration) in built image. 489 Please refer doc/README.pblimage for more details 490 491 CONFIG_SYS_FSL_PBL_RCW 492 It adds PBI(pre-boot instructions) commands in u-boot build image. 493 PBI commands can be used to configure SoC before it starts the execution. 494 Please refer doc/README.pblimage for more details 495 496 CONFIG_SPL_FSL_PBL 497 It adds a target to create boot binary having SPL binary in PBI format 498 concatenated with u-boot binary. 499 500 CONFIG_SYS_FSL_DDR_BE 501 Defines the DDR controller register space as Big Endian 502 503 CONFIG_SYS_FSL_DDR_LE 504 Defines the DDR controller register space as Little Endian 505 506 CONFIG_SYS_FSL_DDR_SDRAM_BASE_PHY 507 Physical address from the view of DDR controllers. It is the 508 same as CONFIG_SYS_DDR_SDRAM_BASE for all Power SoCs. But 509 it could be different for ARM SoCs. 510 511 CONFIG_SYS_FSL_DDR_INTLV_256B 512 DDR controller interleaving on 256-byte. This is a special 513 interleaving mode, handled by Dickens for Freescale layerscape 514 SoCs with ARM core. 515 516 CONFIG_SYS_FSL_DDR_MAIN_NUM_CTRLS 517 Number of controllers used as main memory. 518 519 CONFIG_SYS_FSL_OTHER_DDR_NUM_CTRLS 520 Number of controllers used for other than main memory. 521 522 CONFIG_SYS_FSL_HAS_DP_DDR 523 Defines the SoC has DP-DDR used for DPAA. 524 525 CONFIG_SYS_FSL_SEC_BE 526 Defines the SEC controller register space as Big Endian 527 528 CONFIG_SYS_FSL_SEC_LE 529 Defines the SEC controller register space as Little Endian 530 531- MIPS CPU options: 532 CONFIG_SYS_INIT_SP_OFFSET 533 534 Offset relative to CONFIG_SYS_SDRAM_BASE for initial stack 535 pointer. This is needed for the temporary stack before 536 relocation. 537 538 CONFIG_SYS_MIPS_CACHE_MODE 539 540 Cache operation mode for the MIPS CPU. 541 See also arch/mips/include/asm/mipsregs.h. 542 Possible values are: 543 CONF_CM_CACHABLE_NO_WA 544 CONF_CM_CACHABLE_WA 545 CONF_CM_UNCACHED 546 CONF_CM_CACHABLE_NONCOHERENT 547 CONF_CM_CACHABLE_CE 548 CONF_CM_CACHABLE_COW 549 CONF_CM_CACHABLE_CUW 550 CONF_CM_CACHABLE_ACCELERATED 551 552 CONFIG_SYS_XWAY_EBU_BOOTCFG 553 554 Special option for Lantiq XWAY SoCs for booting from NOR flash. 555 See also arch/mips/cpu/mips32/start.S. 556 557 CONFIG_XWAY_SWAP_BYTES 558 559 Enable compilation of tools/xway-swap-bytes needed for Lantiq 560 XWAY SoCs for booting from NOR flash. The U-Boot image needs to 561 be swapped if a flash programmer is used. 562 563- ARM options: 564 CONFIG_SYS_EXCEPTION_VECTORS_HIGH 565 566 Select high exception vectors of the ARM core, e.g., do not 567 clear the V bit of the c1 register of CP15. 568 569 COUNTER_FREQUENCY 570 Generic timer clock source frequency. 571 572 COUNTER_FREQUENCY_REAL 573 Generic timer clock source frequency if the real clock is 574 different from COUNTER_FREQUENCY, and can only be determined 575 at run time. 576 577- Tegra SoC options: 578 CONFIG_TEGRA_SUPPORT_NON_SECURE 579 580 Support executing U-Boot in non-secure (NS) mode. Certain 581 impossible actions will be skipped if the CPU is in NS mode, 582 such as ARM architectural timer initialization. 583 584- Linux Kernel Interface: 585 CONFIG_CLOCKS_IN_MHZ 586 587 U-Boot stores all clock information in Hz 588 internally. For binary compatibility with older Linux 589 kernels (which expect the clocks passed in the 590 bd_info data to be in MHz) the environment variable 591 "clocks_in_mhz" can be defined so that U-Boot 592 converts clock data to MHZ before passing it to the 593 Linux kernel. 594 When CONFIG_CLOCKS_IN_MHZ is defined, a definition of 595 "clocks_in_mhz=1" is automatically included in the 596 default environment. 597 598 CONFIG_MEMSIZE_IN_BYTES [relevant for MIPS only] 599 600 When transferring memsize parameter to Linux, some versions 601 expect it to be in bytes, others in MB. 602 Define CONFIG_MEMSIZE_IN_BYTES to make it in bytes. 603 604 CONFIG_OF_LIBFDT 605 606 New kernel versions are expecting firmware settings to be 607 passed using flattened device trees (based on open firmware 608 concepts). 609 610 CONFIG_OF_LIBFDT 611 * New libfdt-based support 612 * Adds the "fdt" command 613 * The bootm command automatically updates the fdt 614 615 OF_TBCLK - The timebase frequency. 616 OF_STDOUT_PATH - The path to the console device 617 618 boards with QUICC Engines require OF_QE to set UCC MAC 619 addresses 620 621 CONFIG_OF_BOARD_SETUP 622 623 Board code has addition modification that it wants to make 624 to the flat device tree before handing it off to the kernel 625 626 CONFIG_OF_SYSTEM_SETUP 627 628 Other code has addition modification that it wants to make 629 to the flat device tree before handing it off to the kernel. 630 This causes ft_system_setup() to be called before booting 631 the kernel. 632 633 CONFIG_OF_IDE_FIXUP 634 635 U-Boot can detect if an IDE device is present or not. 636 If not, and this new config option is activated, U-Boot 637 removes the ATA node from the DTS before booting Linux, 638 so the Linux IDE driver does not probe the device and 639 crash. This is needed for buggy hardware (uc101) where 640 no pull down resistor is connected to the signal IDE5V_DD7. 641 642 CONFIG_MACH_TYPE [relevant for ARM only][mandatory] 643 644 This setting is mandatory for all boards that have only one 645 machine type and must be used to specify the machine type 646 number as it appears in the ARM machine registry 647 (see http://www.arm.linux.org.uk/developer/machines/). 648 Only boards that have multiple machine types supported 649 in a single configuration file and the machine type is 650 runtime discoverable, do not have to use this setting. 651 652- vxWorks boot parameters: 653 654 bootvx constructs a valid bootline using the following 655 environments variables: bootdev, bootfile, ipaddr, netmask, 656 serverip, gatewayip, hostname, othbootargs. 657 It loads the vxWorks image pointed bootfile. 658 659 Note: If a "bootargs" environment is defined, it will overwride 660 the defaults discussed just above. 661 662- Cache Configuration: 663 CONFIG_SYS_ICACHE_OFF - Do not enable instruction cache in U-Boot 664 CONFIG_SYS_DCACHE_OFF - Do not enable data cache in U-Boot 665 CONFIG_SYS_L2CACHE_OFF- Do not enable L2 cache in U-Boot 666 667- Cache Configuration for ARM: 668 CONFIG_SYS_L2_PL310 - Enable support for ARM PL310 L2 cache 669 controller 670 CONFIG_SYS_PL310_BASE - Physical base address of PL310 671 controller register space 672 673- Serial Ports: 674 CONFIG_PL010_SERIAL 675 676 Define this if you want support for Amba PrimeCell PL010 UARTs. 677 678 CONFIG_PL011_SERIAL 679 680 Define this if you want support for Amba PrimeCell PL011 UARTs. 681 682 CONFIG_PL011_CLOCK 683 684 If you have Amba PrimeCell PL011 UARTs, set this variable to 685 the clock speed of the UARTs. 686 687 CONFIG_PL01x_PORTS 688 689 If you have Amba PrimeCell PL010 or PL011 UARTs on your board, 690 define this to a list of base addresses for each (supported) 691 port. See e.g. include/configs/versatile.h 692 693 CONFIG_SERIAL_HW_FLOW_CONTROL 694 695 Define this variable to enable hw flow control in serial driver. 696 Current user of this option is drivers/serial/nsl16550.c driver 697 698- Console Baudrate: 699 CONFIG_BAUDRATE - in bps 700 Select one of the baudrates listed in 701 CONFIG_SYS_BAUDRATE_TABLE, see below. 702 703- Autoboot Command: 704 CONFIG_BOOTCOMMAND 705 Only needed when CONFIG_BOOTDELAY is enabled; 706 define a command string that is automatically executed 707 when no character is read on the console interface 708 within "Boot Delay" after reset. 709 710 CONFIG_RAMBOOT and CONFIG_NFSBOOT 711 The value of these goes into the environment as 712 "ramboot" and "nfsboot" respectively, and can be used 713 as a convenience, when switching between booting from 714 RAM and NFS. 715 716- Bootcount: 717 CONFIG_BOOTCOUNT_ENV 718 If no softreset save registers are found on the hardware 719 "bootcount" is stored in the environment. To prevent a 720 saveenv on all reboots, the environment variable 721 "upgrade_available" is used. If "upgrade_available" is 722 0, "bootcount" is always 0, if "upgrade_available" is 723 1 "bootcount" is incremented in the environment. 724 So the Userspace Applikation must set the "upgrade_available" 725 and "bootcount" variable to 0, if a boot was successfully. 726 727- Pre-Boot Commands: 728 CONFIG_PREBOOT 729 730 When this option is #defined, the existence of the 731 environment variable "preboot" will be checked 732 immediately before starting the CONFIG_BOOTDELAY 733 countdown and/or running the auto-boot command resp. 734 entering interactive mode. 735 736 This feature is especially useful when "preboot" is 737 automatically generated or modified. For an example 738 see the LWMON board specific code: here "preboot" is 739 modified when the user holds down a certain 740 combination of keys on the (special) keyboard when 741 booting the systems 742 743- Serial Download Echo Mode: 744 CONFIG_LOADS_ECHO 745 If defined to 1, all characters received during a 746 serial download (using the "loads" command) are 747 echoed back. This might be needed by some terminal 748 emulations (like "cu"), but may as well just take 749 time on others. This setting #define's the initial 750 value of the "loads_echo" environment variable. 751 752- Kgdb Serial Baudrate: (if CONFIG_CMD_KGDB is defined) 753 CONFIG_KGDB_BAUDRATE 754 Select one of the baudrates listed in 755 CONFIG_SYS_BAUDRATE_TABLE, see below. 756 757- Removal of commands 758 If no commands are needed to boot, you can disable 759 CONFIG_CMDLINE to remove them. In this case, the command line 760 will not be available, and when U-Boot wants to execute the 761 boot command (on start-up) it will call board_run_command() 762 instead. This can reduce image size significantly for very 763 simple boot procedures. 764 765- Regular expression support: 766 CONFIG_REGEX 767 If this variable is defined, U-Boot is linked against 768 the SLRE (Super Light Regular Expression) library, 769 which adds regex support to some commands, as for 770 example "env grep" and "setexpr". 771 772- Device tree: 773 CONFIG_OF_CONTROL 774 If this variable is defined, U-Boot will use a device tree 775 to configure its devices, instead of relying on statically 776 compiled #defines in the board file. This option is 777 experimental and only available on a few boards. The device 778 tree is available in the global data as gd->fdt_blob. 779 780 U-Boot needs to get its device tree from somewhere. This can 781 be done using one of the three options below: 782 783 CONFIG_OF_EMBED 784 If this variable is defined, U-Boot will embed a device tree 785 binary in its image. This device tree file should be in the 786 board directory and called <soc>-<board>.dts. The binary file 787 is then picked up in board_init_f() and made available through 788 the global data structure as gd->fdt_blob. 789 790 CONFIG_OF_SEPARATE 791 If this variable is defined, U-Boot will build a device tree 792 binary. It will be called u-boot.dtb. Architecture-specific 793 code will locate it at run-time. Generally this works by: 794 795 cat u-boot.bin u-boot.dtb >image.bin 796 797 and in fact, U-Boot does this for you, creating a file called 798 u-boot-dtb.bin which is useful in the common case. You can 799 still use the individual files if you need something more 800 exotic. 801 802 CONFIG_OF_BOARD 803 If this variable is defined, U-Boot will use the device tree 804 provided by the board at runtime instead of embedding one with 805 the image. Only boards defining board_fdt_blob_setup() support 806 this option (see include/fdtdec.h file). 807 808- Watchdog: 809 CONFIG_WATCHDOG 810 If this variable is defined, it enables watchdog 811 support for the SoC. There must be support in the SoC 812 specific code for a watchdog. For the 8xx 813 CPUs, the SIU Watchdog feature is enabled in the SYPCR 814 register. When supported for a specific SoC is 815 available, then no further board specific code should 816 be needed to use it. 817 818 CONFIG_HW_WATCHDOG 819 When using a watchdog circuitry external to the used 820 SoC, then define this variable and provide board 821 specific code for the "hw_watchdog_reset" function. 822 823 CONFIG_AT91_HW_WDT_TIMEOUT 824 specify the timeout in seconds. default 2 seconds. 825 826- U-Boot Version: 827 CONFIG_VERSION_VARIABLE 828 If this variable is defined, an environment variable 829 named "ver" is created by U-Boot showing the U-Boot 830 version as printed by the "version" command. 831 Any change to this variable will be reverted at the 832 next reset. 833 834- Real-Time Clock: 835 836 When CONFIG_CMD_DATE is selected, the type of the RTC 837 has to be selected, too. Define exactly one of the 838 following options: 839 840 CONFIG_RTC_PCF8563 - use Philips PCF8563 RTC 841 CONFIG_RTC_MC13XXX - use MC13783 or MC13892 RTC 842 CONFIG_RTC_MC146818 - use MC146818 RTC 843 CONFIG_RTC_DS1307 - use Maxim, Inc. DS1307 RTC 844 CONFIG_RTC_DS1337 - use Maxim, Inc. DS1337 RTC 845 CONFIG_RTC_DS1338 - use Maxim, Inc. DS1338 RTC 846 CONFIG_RTC_DS1339 - use Maxim, Inc. DS1339 RTC 847 CONFIG_RTC_DS164x - use Dallas DS164x RTC 848 CONFIG_RTC_ISL1208 - use Intersil ISL1208 RTC 849 CONFIG_RTC_MAX6900 - use Maxim, Inc. MAX6900 RTC 850 CONFIG_RTC_DS1337_NOOSC - Turn off the OSC output for DS1337 851 CONFIG_SYS_RV3029_TCR - enable trickle charger on 852 RV3029 RTC. 853 854 Note that if the RTC uses I2C, then the I2C interface 855 must also be configured. See I2C Support, below. 856 857- GPIO Support: 858 CONFIG_PCA953X - use NXP's PCA953X series I2C GPIO 859 860 The CONFIG_SYS_I2C_PCA953X_WIDTH option specifies a list of 861 chip-ngpio pairs that tell the PCA953X driver the number of 862 pins supported by a particular chip. 863 864 Note that if the GPIO device uses I2C, then the I2C interface 865 must also be configured. See I2C Support, below. 866 867- I/O tracing: 868 When CONFIG_IO_TRACE is selected, U-Boot intercepts all I/O 869 accesses and can checksum them or write a list of them out 870 to memory. See the 'iotrace' command for details. This is 871 useful for testing device drivers since it can confirm that 872 the driver behaves the same way before and after a code 873 change. Currently this is supported on sandbox and arm. To 874 add support for your architecture, add '#include <iotrace.h>' 875 to the bottom of arch/<arch>/include/asm/io.h and test. 876 877 Example output from the 'iotrace stats' command is below. 878 Note that if the trace buffer is exhausted, the checksum will 879 still continue to operate. 880 881 iotrace is enabled 882 Start: 10000000 (buffer start address) 883 Size: 00010000 (buffer size) 884 Offset: 00000120 (current buffer offset) 885 Output: 10000120 (start + offset) 886 Count: 00000018 (number of trace records) 887 CRC32: 9526fb66 (CRC32 of all trace records) 888 889- Timestamp Support: 890 891 When CONFIG_TIMESTAMP is selected, the timestamp 892 (date and time) of an image is printed by image 893 commands like bootm or iminfo. This option is 894 automatically enabled when you select CONFIG_CMD_DATE . 895 896- Partition Labels (disklabels) Supported: 897 Zero or more of the following: 898 CONFIG_MAC_PARTITION Apple's MacOS partition table. 899 CONFIG_ISO_PARTITION ISO partition table, used on CDROM etc. 900 CONFIG_EFI_PARTITION GPT partition table, common when EFI is the 901 bootloader. Note 2TB partition limit; see 902 disk/part_efi.c 903 CONFIG_MTD_PARTITIONS Memory Technology Device partition table. 904 905 If IDE or SCSI support is enabled (CONFIG_IDE or 906 CONFIG_SCSI) you must configure support for at 907 least one non-MTD partition type as well. 908 909- IDE Reset method: 910 CONFIG_IDE_RESET_ROUTINE - this is defined in several 911 board configurations files but used nowhere! 912 913 CONFIG_IDE_RESET - is this is defined, IDE Reset will 914 be performed by calling the function 915 ide_set_reset(int reset) 916 which has to be defined in a board specific file 917 918- ATAPI Support: 919 CONFIG_ATAPI 920 921 Set this to enable ATAPI support. 922 923- LBA48 Support 924 CONFIG_LBA48 925 926 Set this to enable support for disks larger than 137GB 927 Also look at CONFIG_SYS_64BIT_LBA. 928 Whithout these , LBA48 support uses 32bit variables and will 'only' 929 support disks up to 2.1TB. 930 931 CONFIG_SYS_64BIT_LBA: 932 When enabled, makes the IDE subsystem use 64bit sector addresses. 933 Default is 32bit. 934 935- SCSI Support: 936 CONFIG_SYS_SCSI_MAX_LUN [8], CONFIG_SYS_SCSI_MAX_SCSI_ID [7] and 937 CONFIG_SYS_SCSI_MAX_DEVICE [CONFIG_SYS_SCSI_MAX_SCSI_ID * 938 CONFIG_SYS_SCSI_MAX_LUN] can be adjusted to define the 939 maximum numbers of LUNs, SCSI ID's and target 940 devices. 941 942 The environment variable 'scsidevs' is set to the number of 943 SCSI devices found during the last scan. 944 945- NETWORK Support (PCI): 946 CONFIG_E1000 947 Support for Intel 8254x/8257x gigabit chips. 948 949 CONFIG_E1000_SPI 950 Utility code for direct access to the SPI bus on Intel 8257x. 951 This does not do anything useful unless you set at least one 952 of CONFIG_CMD_E1000 or CONFIG_E1000_SPI_GENERIC. 953 954 CONFIG_E1000_SPI_GENERIC 955 Allow generic access to the SPI bus on the Intel 8257x, for 956 example with the "sspi" command. 957 958 CONFIG_EEPRO100 959 Support for Intel 82557/82559/82559ER chips. 960 Optional CONFIG_EEPRO100_SROM_WRITE enables EEPROM 961 write routine for first time initialisation. 962 963 CONFIG_TULIP 964 Support for Digital 2114x chips. 965 Optional CONFIG_TULIP_SELECT_MEDIA for board specific 966 modem chip initialisation (KS8761/QS6611). 967 968 CONFIG_NATSEMI 969 Support for National dp83815 chips. 970 971 CONFIG_NS8382X 972 Support for National dp8382[01] gigabit chips. 973 974- NETWORK Support (other): 975 976 CONFIG_DRIVER_AT91EMAC 977 Support for AT91RM9200 EMAC. 978 979 CONFIG_RMII 980 Define this to use reduced MII inteface 981 982 CONFIG_DRIVER_AT91EMAC_QUIET 983 If this defined, the driver is quiet. 984 The driver doen't show link status messages. 985 986 CONFIG_CALXEDA_XGMAC 987 Support for the Calxeda XGMAC device 988 989 CONFIG_LAN91C96 990 Support for SMSC's LAN91C96 chips. 991 992 CONFIG_LAN91C96_USE_32_BIT 993 Define this to enable 32 bit addressing 994 995 CONFIG_SMC91111 996 Support for SMSC's LAN91C111 chip 997 998 CONFIG_SMC91111_BASE 999 Define this to hold the physical address 1000 of the device (I/O space) 1001 1002 CONFIG_SMC_USE_32_BIT 1003 Define this if data bus is 32 bits 1004 1005 CONFIG_SMC_USE_IOFUNCS 1006 Define this to use i/o functions instead of macros 1007 (some hardware wont work with macros) 1008 1009 CONFIG_DRIVER_TI_EMAC 1010 Support for davinci emac 1011 1012 CONFIG_SYS_DAVINCI_EMAC_PHY_COUNT 1013 Define this if you have more then 3 PHYs. 1014 1015 CONFIG_FTGMAC100 1016 Support for Faraday's FTGMAC100 Gigabit SoC Ethernet 1017 1018 CONFIG_FTGMAC100_EGIGA 1019 Define this to use GE link update with gigabit PHY. 1020 Define this if FTGMAC100 is connected to gigabit PHY. 1021 If your system has 10/100 PHY only, it might not occur 1022 wrong behavior. Because PHY usually return timeout or 1023 useless data when polling gigabit status and gigabit 1024 control registers. This behavior won't affect the 1025 correctnessof 10/100 link speed update. 1026 1027 CONFIG_SH_ETHER 1028 Support for Renesas on-chip Ethernet controller 1029 1030 CONFIG_SH_ETHER_USE_PORT 1031 Define the number of ports to be used 1032 1033 CONFIG_SH_ETHER_PHY_ADDR 1034 Define the ETH PHY's address 1035 1036 CONFIG_SH_ETHER_CACHE_WRITEBACK 1037 If this option is set, the driver enables cache flush. 1038 1039- PWM Support: 1040 CONFIG_PWM_IMX 1041 Support for PWM module on the imx6. 1042 1043- TPM Support: 1044 CONFIG_TPM 1045 Support TPM devices. 1046 1047 CONFIG_TPM_TIS_INFINEON 1048 Support for Infineon i2c bus TPM devices. Only one device 1049 per system is supported at this time. 1050 1051 CONFIG_TPM_TIS_I2C_BURST_LIMITATION 1052 Define the burst count bytes upper limit 1053 1054 CONFIG_TPM_ST33ZP24 1055 Support for STMicroelectronics TPM devices. Requires DM_TPM support. 1056 1057 CONFIG_TPM_ST33ZP24_I2C 1058 Support for STMicroelectronics ST33ZP24 I2C devices. 1059 Requires TPM_ST33ZP24 and I2C. 1060 1061 CONFIG_TPM_ST33ZP24_SPI 1062 Support for STMicroelectronics ST33ZP24 SPI devices. 1063 Requires TPM_ST33ZP24 and SPI. 1064 1065 CONFIG_TPM_ATMEL_TWI 1066 Support for Atmel TWI TPM device. Requires I2C support. 1067 1068 CONFIG_TPM_TIS_LPC 1069 Support for generic parallel port TPM devices. Only one device 1070 per system is supported at this time. 1071 1072 CONFIG_TPM_TIS_BASE_ADDRESS 1073 Base address where the generic TPM device is mapped 1074 to. Contemporary x86 systems usually map it at 1075 0xfed40000. 1076 1077 CONFIG_TPM 1078 Define this to enable the TPM support library which provides 1079 functional interfaces to some TPM commands. 1080 Requires support for a TPM device. 1081 1082 CONFIG_TPM_AUTH_SESSIONS 1083 Define this to enable authorized functions in the TPM library. 1084 Requires CONFIG_TPM and CONFIG_SHA1. 1085 1086- USB Support: 1087 At the moment only the UHCI host controller is 1088 supported (PIP405, MIP405); define 1089 CONFIG_USB_UHCI to enable it. 1090 define CONFIG_USB_KEYBOARD to enable the USB Keyboard 1091 and define CONFIG_USB_STORAGE to enable the USB 1092 storage devices. 1093 Note: 1094 Supported are USB Keyboards and USB Floppy drives 1095 (TEAC FD-05PUB). 1096 1097 CONFIG_USB_EHCI_TXFIFO_THRESH enables setting of the 1098 txfilltuning field in the EHCI controller on reset. 1099 1100 CONFIG_USB_DWC2_REG_ADDR the physical CPU address of the DWC2 1101 HW module registers. 1102 1103- USB Device: 1104 Define the below if you wish to use the USB console. 1105 Once firmware is rebuilt from a serial console issue the 1106 command "setenv stdin usbtty; setenv stdout usbtty" and 1107 attach your USB cable. The Unix command "dmesg" should print 1108 it has found a new device. The environment variable usbtty 1109 can be set to gserial or cdc_acm to enable your device to 1110 appear to a USB host as a Linux gserial device or a 1111 Common Device Class Abstract Control Model serial device. 1112 If you select usbtty = gserial you should be able to enumerate 1113 a Linux host by 1114 # modprobe usbserial vendor=0xVendorID product=0xProductID 1115 else if using cdc_acm, simply setting the environment 1116 variable usbtty to be cdc_acm should suffice. The following 1117 might be defined in YourBoardName.h 1118 1119 CONFIG_USB_DEVICE 1120 Define this to build a UDC device 1121 1122 CONFIG_USB_TTY 1123 Define this to have a tty type of device available to 1124 talk to the UDC device 1125 1126 CONFIG_USBD_HS 1127 Define this to enable the high speed support for usb 1128 device and usbtty. If this feature is enabled, a routine 1129 int is_usbd_high_speed(void) 1130 also needs to be defined by the driver to dynamically poll 1131 whether the enumeration has succeded at high speed or full 1132 speed. 1133 1134 CONFIG_SYS_CONSOLE_IS_IN_ENV 1135 Define this if you want stdin, stdout &/or stderr to 1136 be set to usbtty. 1137 1138 If you have a USB-IF assigned VendorID then you may wish to 1139 define your own vendor specific values either in BoardName.h 1140 or directly in usbd_vendor_info.h. If you don't define 1141 CONFIG_USBD_MANUFACTURER, CONFIG_USBD_PRODUCT_NAME, 1142 CONFIG_USBD_VENDORID and CONFIG_USBD_PRODUCTID, then U-Boot 1143 should pretend to be a Linux device to it's target host. 1144 1145 CONFIG_USBD_MANUFACTURER 1146 Define this string as the name of your company for 1147 - CONFIG_USBD_MANUFACTURER "my company" 1148 1149 CONFIG_USBD_PRODUCT_NAME 1150 Define this string as the name of your product 1151 - CONFIG_USBD_PRODUCT_NAME "acme usb device" 1152 1153 CONFIG_USBD_VENDORID 1154 Define this as your assigned Vendor ID from the USB 1155 Implementors Forum. This *must* be a genuine Vendor ID 1156 to avoid polluting the USB namespace. 1157 - CONFIG_USBD_VENDORID 0xFFFF 1158 1159 CONFIG_USBD_PRODUCTID 1160 Define this as the unique Product ID 1161 for your device 1162 - CONFIG_USBD_PRODUCTID 0xFFFF 1163 1164- ULPI Layer Support: 1165 The ULPI (UTMI Low Pin (count) Interface) PHYs are supported via 1166 the generic ULPI layer. The generic layer accesses the ULPI PHY 1167 via the platform viewport, so you need both the genric layer and 1168 the viewport enabled. Currently only Chipidea/ARC based 1169 viewport is supported. 1170 To enable the ULPI layer support, define CONFIG_USB_ULPI and 1171 CONFIG_USB_ULPI_VIEWPORT in your board configuration file. 1172 If your ULPI phy needs a different reference clock than the 1173 standard 24 MHz then you have to define CONFIG_ULPI_REF_CLK to 1174 the appropriate value in Hz. 1175 1176- MMC Support: 1177 The MMC controller on the Intel PXA is supported. To 1178 enable this define CONFIG_MMC. The MMC can be 1179 accessed from the boot prompt by mapping the device 1180 to physical memory similar to flash. Command line is 1181 enabled with CONFIG_CMD_MMC. The MMC driver also works with 1182 the FAT fs. This is enabled with CONFIG_CMD_FAT. 1183 1184 CONFIG_SH_MMCIF 1185 Support for Renesas on-chip MMCIF controller 1186 1187 CONFIG_SH_MMCIF_ADDR 1188 Define the base address of MMCIF registers 1189 1190 CONFIG_SH_MMCIF_CLK 1191 Define the clock frequency for MMCIF 1192 1193 CONFIG_SUPPORT_EMMC_BOOT 1194 Enable some additional features of the eMMC boot partitions. 1195 1196 CONFIG_SUPPORT_EMMC_RPMB 1197 Enable the commands for reading, writing and programming the 1198 key for the Replay Protection Memory Block partition in eMMC. 1199 1200- USB Device Firmware Update (DFU) class support: 1201 CONFIG_USB_FUNCTION_DFU 1202 This enables the USB portion of the DFU USB class 1203 1204 CONFIG_DFU_MMC 1205 This enables support for exposing (e)MMC devices via DFU. 1206 1207 CONFIG_DFU_NAND 1208 This enables support for exposing NAND devices via DFU. 1209 1210 CONFIG_DFU_RAM 1211 This enables support for exposing RAM via DFU. 1212 Note: DFU spec refer to non-volatile memory usage, but 1213 allow usages beyond the scope of spec - here RAM usage, 1214 one that would help mostly the developer. 1215 1216 CONFIG_SYS_DFU_DATA_BUF_SIZE 1217 Dfu transfer uses a buffer before writing data to the 1218 raw storage device. Make the size (in bytes) of this buffer 1219 configurable. The size of this buffer is also configurable 1220 through the "dfu_bufsiz" environment variable. 1221 1222 CONFIG_SYS_DFU_MAX_FILE_SIZE 1223 When updating files rather than the raw storage device, 1224 we use a static buffer to copy the file into and then write 1225 the buffer once we've been given the whole file. Define 1226 this to the maximum filesize (in bytes) for the buffer. 1227 Default is 4 MiB if undefined. 1228 1229 DFU_DEFAULT_POLL_TIMEOUT 1230 Poll timeout [ms], is the timeout a device can send to the 1231 host. The host must wait for this timeout before sending 1232 a subsequent DFU_GET_STATUS request to the device. 1233 1234 DFU_MANIFEST_POLL_TIMEOUT 1235 Poll timeout [ms], which the device sends to the host when 1236 entering dfuMANIFEST state. Host waits this timeout, before 1237 sending again an USB request to the device. 1238 1239- Journaling Flash filesystem support: 1240 CONFIG_JFFS2_NAND 1241 Define these for a default partition on a NAND device 1242 1243 CONFIG_SYS_JFFS2_FIRST_SECTOR, 1244 CONFIG_SYS_JFFS2_FIRST_BANK, CONFIG_SYS_JFFS2_NUM_BANKS 1245 Define these for a default partition on a NOR device 1246 1247- Keyboard Support: 1248 See Kconfig help for available keyboard drivers. 1249 1250 CONFIG_KEYBOARD 1251 1252 Define this to enable a custom keyboard support. 1253 This simply calls drv_keyboard_init() which must be 1254 defined in your board-specific files. This option is deprecated 1255 and is only used by novena. For new boards, use driver model 1256 instead. 1257 1258- Video support: 1259 CONFIG_FSL_DIU_FB 1260 Enable the Freescale DIU video driver. Reference boards for 1261 SOCs that have a DIU should define this macro to enable DIU 1262 support, and should also define these other macros: 1263 1264 CONFIG_SYS_DIU_ADDR 1265 CONFIG_VIDEO 1266 CONFIG_CFB_CONSOLE 1267 CONFIG_VIDEO_SW_CURSOR 1268 CONFIG_VGA_AS_SINGLE_DEVICE 1269 CONFIG_VIDEO_LOGO 1270 CONFIG_VIDEO_BMP_LOGO 1271 1272 The DIU driver will look for the 'video-mode' environment 1273 variable, and if defined, enable the DIU as a console during 1274 boot. See the documentation file doc/README.video for a 1275 description of this variable. 1276 1277- LCD Support: CONFIG_LCD 1278 1279 Define this to enable LCD support (for output to LCD 1280 display); also select one of the supported displays 1281 by defining one of these: 1282 1283 CONFIG_ATMEL_LCD: 1284 1285 HITACHI TX09D70VM1CCA, 3.5", 240x320. 1286 1287 CONFIG_NEC_NL6448AC33: 1288 1289 NEC NL6448AC33-18. Active, color, single scan. 1290 1291 CONFIG_NEC_NL6448BC20 1292 1293 NEC NL6448BC20-08. 6.5", 640x480. 1294 Active, color, single scan. 1295 1296 CONFIG_NEC_NL6448BC33_54 1297 1298 NEC NL6448BC33-54. 10.4", 640x480. 1299 Active, color, single scan. 1300 1301 CONFIG_SHARP_16x9 1302 1303 Sharp 320x240. Active, color, single scan. 1304 It isn't 16x9, and I am not sure what it is. 1305 1306 CONFIG_SHARP_LQ64D341 1307 1308 Sharp LQ64D341 display, 640x480. 1309 Active, color, single scan. 1310 1311 CONFIG_HLD1045 1312 1313 HLD1045 display, 640x480. 1314 Active, color, single scan. 1315 1316 CONFIG_OPTREX_BW 1317 1318 Optrex CBL50840-2 NF-FW 99 22 M5 1319 or 1320 Hitachi LMG6912RPFC-00T 1321 or 1322 Hitachi SP14Q002 1323 1324 320x240. Black & white. 1325 1326 CONFIG_LCD_ALIGNMENT 1327 1328 Normally the LCD is page-aligned (typically 4KB). If this is 1329 defined then the LCD will be aligned to this value instead. 1330 For ARM it is sometimes useful to use MMU_SECTION_SIZE 1331 here, since it is cheaper to change data cache settings on 1332 a per-section basis. 1333 1334 1335 CONFIG_LCD_ROTATION 1336 1337 Sometimes, for example if the display is mounted in portrait 1338 mode or even if it's mounted landscape but rotated by 180degree, 1339 we need to rotate our content of the display relative to the 1340 framebuffer, so that user can read the messages which are 1341 printed out. 1342 Once CONFIG_LCD_ROTATION is defined, the lcd_console will be 1343 initialized with a given rotation from "vl_rot" out of 1344 "vidinfo_t" which is provided by the board specific code. 1345 The value for vl_rot is coded as following (matching to 1346 fbcon=rotate:<n> linux-kernel commandline): 1347 0 = no rotation respectively 0 degree 1348 1 = 90 degree rotation 1349 2 = 180 degree rotation 1350 3 = 270 degree rotation 1351 1352 If CONFIG_LCD_ROTATION is not defined, the console will be 1353 initialized with 0degree rotation. 1354 1355 CONFIG_LCD_BMP_RLE8 1356 1357 Support drawing of RLE8-compressed bitmaps on the LCD. 1358 1359 CONFIG_I2C_EDID 1360 1361 Enables an 'i2c edid' command which can read EDID 1362 information over I2C from an attached LCD display. 1363 1364- Splash Screen Support: CONFIG_SPLASH_SCREEN 1365 1366 If this option is set, the environment is checked for 1367 a variable "splashimage". If found, the usual display 1368 of logo, copyright and system information on the LCD 1369 is suppressed and the BMP image at the address 1370 specified in "splashimage" is loaded instead. The 1371 console is redirected to the "nulldev", too. This 1372 allows for a "silent" boot where a splash screen is 1373 loaded very quickly after power-on. 1374 1375 CONFIG_SPLASHIMAGE_GUARD 1376 1377 If this option is set, then U-Boot will prevent the environment 1378 variable "splashimage" from being set to a problematic address 1379 (see doc/README.displaying-bmps). 1380 This option is useful for targets where, due to alignment 1381 restrictions, an improperly aligned BMP image will cause a data 1382 abort. If you think you will not have problems with unaligned 1383 accesses (for example because your toolchain prevents them) 1384 there is no need to set this option. 1385 1386 CONFIG_SPLASH_SCREEN_ALIGN 1387 1388 If this option is set the splash image can be freely positioned 1389 on the screen. Environment variable "splashpos" specifies the 1390 position as "x,y". If a positive number is given it is used as 1391 number of pixel from left/top. If a negative number is given it 1392 is used as number of pixel from right/bottom. You can also 1393 specify 'm' for centering the image. 1394 1395 Example: 1396 setenv splashpos m,m 1397 => image at center of screen 1398 1399 setenv splashpos 30,20 1400 => image at x = 30 and y = 20 1401 1402 setenv splashpos -10,m 1403 => vertically centered image 1404 at x = dspWidth - bmpWidth - 9 1405 1406- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP 1407 1408 If this option is set, additionally to standard BMP 1409 images, gzipped BMP images can be displayed via the 1410 splashscreen support or the bmp command. 1411 1412- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8 1413 1414 If this option is set, 8-bit RLE compressed BMP images 1415 can be displayed via the splashscreen support or the 1416 bmp command. 1417 1418- Compression support: 1419 CONFIG_GZIP 1420 1421 Enabled by default to support gzip compressed images. 1422 1423 CONFIG_BZIP2 1424 1425 If this option is set, support for bzip2 compressed 1426 images is included. If not, only uncompressed and gzip 1427 compressed images are supported. 1428 1429 NOTE: the bzip2 algorithm requires a lot of RAM, so 1430 the malloc area (as defined by CONFIG_SYS_MALLOC_LEN) should 1431 be at least 4MB. 1432 1433- MII/PHY support: 1434 CONFIG_PHY_ADDR 1435 1436 The address of PHY on MII bus. 1437 1438 CONFIG_PHY_CLOCK_FREQ (ppc4xx) 1439 1440 The clock frequency of the MII bus 1441 1442 CONFIG_PHY_RESET_DELAY 1443 1444 Some PHY like Intel LXT971A need extra delay after 1445 reset before any MII register access is possible. 1446 For such PHY, set this option to the usec delay 1447 required. (minimum 300usec for LXT971A) 1448 1449 CONFIG_PHY_CMD_DELAY (ppc4xx) 1450 1451 Some PHY like Intel LXT971A need extra delay after 1452 command issued before MII status register can be read 1453 1454- IP address: 1455 CONFIG_IPADDR 1456 1457 Define a default value for the IP address to use for 1458 the default Ethernet interface, in case this is not 1459 determined through e.g. bootp. 1460 (Environment variable "ipaddr") 1461 1462- Server IP address: 1463 CONFIG_SERVERIP 1464 1465 Defines a default value for the IP address of a TFTP 1466 server to contact when using the "tftboot" command. 1467 (Environment variable "serverip") 1468 1469 CONFIG_KEEP_SERVERADDR 1470 1471 Keeps the server's MAC address, in the env 'serveraddr' 1472 for passing to bootargs (like Linux's netconsole option) 1473 1474- Gateway IP address: 1475 CONFIG_GATEWAYIP 1476 1477 Defines a default value for the IP address of the 1478 default router where packets to other networks are 1479 sent to. 1480 (Environment variable "gatewayip") 1481 1482- Subnet mask: 1483 CONFIG_NETMASK 1484 1485 Defines a default value for the subnet mask (or 1486 routing prefix) which is used to determine if an IP 1487 address belongs to the local subnet or needs to be 1488 forwarded through a router. 1489 (Environment variable "netmask") 1490 1491- Multicast TFTP Mode: 1492 CONFIG_MCAST_TFTP 1493 1494 Defines whether you want to support multicast TFTP as per 1495 rfc-2090; for example to work with atftp. Lets lots of targets 1496 tftp down the same boot image concurrently. Note: the Ethernet 1497 driver in use must provide a function: mcast() to join/leave a 1498 multicast group. 1499 1500- BOOTP Recovery Mode: 1501 CONFIG_BOOTP_RANDOM_DELAY 1502 1503 If you have many targets in a network that try to 1504 boot using BOOTP, you may want to avoid that all 1505 systems send out BOOTP requests at precisely the same 1506 moment (which would happen for instance at recovery 1507 from a power failure, when all systems will try to 1508 boot, thus flooding the BOOTP server. Defining 1509 CONFIG_BOOTP_RANDOM_DELAY causes a random delay to be 1510 inserted before sending out BOOTP requests. The 1511 following delays are inserted then: 1512 1513 1st BOOTP request: delay 0 ... 1 sec 1514 2nd BOOTP request: delay 0 ... 2 sec 1515 3rd BOOTP request: delay 0 ... 4 sec 1516 4th and following 1517 BOOTP requests: delay 0 ... 8 sec 1518 1519 CONFIG_BOOTP_ID_CACHE_SIZE 1520 1521 BOOTP packets are uniquely identified using a 32-bit ID. The 1522 server will copy the ID from client requests to responses and 1523 U-Boot will use this to determine if it is the destination of 1524 an incoming response. Some servers will check that addresses 1525 aren't in use before handing them out (usually using an ARP 1526 ping) and therefore take up to a few hundred milliseconds to 1527 respond. Network congestion may also influence the time it 1528 takes for a response to make it back to the client. If that 1529 time is too long, U-Boot will retransmit requests. In order 1530 to allow earlier responses to still be accepted after these 1531 retransmissions, U-Boot's BOOTP client keeps a small cache of 1532 IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this 1533 cache. The default is to keep IDs for up to four outstanding 1534 requests. Increasing this will allow U-Boot to accept offers 1535 from a BOOTP client in networks with unusually high latency. 1536 1537- DHCP Advanced Options: 1538 You can fine tune the DHCP functionality by defining 1539 CONFIG_BOOTP_* symbols: 1540 1541 CONFIG_BOOTP_SUBNETMASK 1542 CONFIG_BOOTP_GATEWAY 1543 CONFIG_BOOTP_HOSTNAME 1544 CONFIG_BOOTP_NISDOMAIN 1545 CONFIG_BOOTP_BOOTPATH 1546 CONFIG_BOOTP_BOOTFILESIZE 1547 CONFIG_BOOTP_DNS 1548 CONFIG_BOOTP_DNS2 1549 CONFIG_BOOTP_SEND_HOSTNAME 1550 CONFIG_BOOTP_NTPSERVER 1551 CONFIG_BOOTP_TIMEOFFSET 1552 CONFIG_BOOTP_VENDOREX 1553 CONFIG_BOOTP_MAY_FAIL 1554 1555 CONFIG_BOOTP_SERVERIP - TFTP server will be the serverip 1556 environment variable, not the BOOTP server. 1557 1558 CONFIG_BOOTP_MAY_FAIL - If the DHCP server is not found 1559 after the configured retry count, the call will fail 1560 instead of starting over. This can be used to fail over 1561 to Link-local IP address configuration if the DHCP server 1562 is not available. 1563 1564 CONFIG_BOOTP_DNS2 - If a DHCP client requests the DNS 1565 serverip from a DHCP server, it is possible that more 1566 than one DNS serverip is offered to the client. 1567 If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS 1568 serverip will be stored in the additional environment 1569 variable "dnsip2". The first DNS serverip is always 1570 stored in the variable "dnsip", when CONFIG_BOOTP_DNS 1571 is defined. 1572 1573 CONFIG_BOOTP_SEND_HOSTNAME - Some DHCP servers are capable 1574 to do a dynamic update of a DNS server. To do this, they 1575 need the hostname of the DHCP requester. 1576 If CONFIG_BOOTP_SEND_HOSTNAME is defined, the content 1577 of the "hostname" environment variable is passed as 1578 option 12 to the DHCP server. 1579 1580 CONFIG_BOOTP_DHCP_REQUEST_DELAY 1581 1582 A 32bit value in microseconds for a delay between 1583 receiving a "DHCP Offer" and sending the "DHCP Request". 1584 This fixes a problem with certain DHCP servers that don't 1585 respond 100% of the time to a "DHCP request". E.g. On an 1586 AT91RM9200 processor running at 180MHz, this delay needed 1587 to be *at least* 15,000 usec before a Windows Server 2003 1588 DHCP server would reply 100% of the time. I recommend at 1589 least 50,000 usec to be safe. The alternative is to hope 1590 that one of the retries will be successful but note that 1591 the DHCP timeout and retry process takes a longer than 1592 this delay. 1593 1594 - Link-local IP address negotiation: 1595 Negotiate with other link-local clients on the local network 1596 for an address that doesn't require explicit configuration. 1597 This is especially useful if a DHCP server cannot be guaranteed 1598 to exist in all environments that the device must operate. 1599 1600 See doc/README.link-local for more information. 1601 1602 - MAC address from environment variables 1603 1604 FDT_SEQ_MACADDR_FROM_ENV 1605 1606 Fix-up device tree with MAC addresses fetched sequentially from 1607 environment variables. This config work on assumption that 1608 non-usable ethernet node of device-tree are either not present 1609 or their status has been marked as "disabled". 1610 1611 - CDP Options: 1612 CONFIG_CDP_DEVICE_ID 1613 1614 The device id used in CDP trigger frames. 1615 1616 CONFIG_CDP_DEVICE_ID_PREFIX 1617 1618 A two character string which is prefixed to the MAC address 1619 of the device. 1620 1621 CONFIG_CDP_PORT_ID 1622 1623 A printf format string which contains the ascii name of 1624 the port. Normally is set to "eth%d" which sets 1625 eth0 for the first Ethernet, eth1 for the second etc. 1626 1627 CONFIG_CDP_CAPABILITIES 1628 1629 A 32bit integer which indicates the device capabilities; 1630 0x00000010 for a normal host which does not forwards. 1631 1632 CONFIG_CDP_VERSION 1633 1634 An ascii string containing the version of the software. 1635 1636 CONFIG_CDP_PLATFORM 1637 1638 An ascii string containing the name of the platform. 1639 1640 CONFIG_CDP_TRIGGER 1641 1642 A 32bit integer sent on the trigger. 1643 1644 CONFIG_CDP_POWER_CONSUMPTION 1645 1646 A 16bit integer containing the power consumption of the 1647 device in .1 of milliwatts. 1648 1649 CONFIG_CDP_APPLIANCE_VLAN_TYPE 1650 1651 A byte containing the id of the VLAN. 1652 1653- Status LED: CONFIG_LED_STATUS 1654 1655 Several configurations allow to display the current 1656 status using a LED. For instance, the LED will blink 1657 fast while running U-Boot code, stop blinking as 1658 soon as a reply to a BOOTP request was received, and 1659 start blinking slow once the Linux kernel is running 1660 (supported by a status LED driver in the Linux 1661 kernel). Defining CONFIG_LED_STATUS enables this 1662 feature in U-Boot. 1663 1664 Additional options: 1665 1666 CONFIG_LED_STATUS_GPIO 1667 The status LED can be connected to a GPIO pin. 1668 In such cases, the gpio_led driver can be used as a 1669 status LED backend implementation. Define CONFIG_LED_STATUS_GPIO 1670 to include the gpio_led driver in the U-Boot binary. 1671 1672 CONFIG_GPIO_LED_INVERTED_TABLE 1673 Some GPIO connected LEDs may have inverted polarity in which 1674 case the GPIO high value corresponds to LED off state and 1675 GPIO low value corresponds to LED on state. 1676 In such cases CONFIG_GPIO_LED_INVERTED_TABLE may be defined 1677 with a list of GPIO LEDs that have inverted polarity. 1678 1679- I2C Support: CONFIG_SYS_I2C 1680 1681 This enable the NEW i2c subsystem, and will allow you to use 1682 i2c commands at the u-boot command line (as long as you set 1683 CONFIG_CMD_I2C in CONFIG_COMMANDS) and communicate with i2c 1684 based realtime clock chips or other i2c devices. See 1685 common/cmd_i2c.c for a description of the command line 1686 interface. 1687 1688 ported i2c driver to the new framework: 1689 - drivers/i2c/soft_i2c.c: 1690 - activate first bus with CONFIG_SYS_I2C_SOFT define 1691 CONFIG_SYS_I2C_SOFT_SPEED and CONFIG_SYS_I2C_SOFT_SLAVE 1692 for defining speed and slave address 1693 - activate second bus with I2C_SOFT_DECLARATIONS2 define 1694 CONFIG_SYS_I2C_SOFT_SPEED_2 and CONFIG_SYS_I2C_SOFT_SLAVE_2 1695 for defining speed and slave address 1696 - activate third bus with I2C_SOFT_DECLARATIONS3 define 1697 CONFIG_SYS_I2C_SOFT_SPEED_3 and CONFIG_SYS_I2C_SOFT_SLAVE_3 1698 for defining speed and slave address 1699 - activate fourth bus with I2C_SOFT_DECLARATIONS4 define 1700 CONFIG_SYS_I2C_SOFT_SPEED_4 and CONFIG_SYS_I2C_SOFT_SLAVE_4 1701 for defining speed and slave address 1702 1703 - drivers/i2c/fsl_i2c.c: 1704 - activate i2c driver with CONFIG_SYS_I2C_FSL 1705 define CONFIG_SYS_FSL_I2C_OFFSET for setting the register 1706 offset CONFIG_SYS_FSL_I2C_SPEED for the i2c speed and 1707 CONFIG_SYS_FSL_I2C_SLAVE for the slave addr of the first 1708 bus. 1709 - If your board supports a second fsl i2c bus, define 1710 CONFIG_SYS_FSL_I2C2_OFFSET for the register offset 1711 CONFIG_SYS_FSL_I2C2_SPEED for the speed and 1712 CONFIG_SYS_FSL_I2C2_SLAVE for the slave address of the 1713 second bus. 1714 1715 - drivers/i2c/tegra_i2c.c: 1716 - activate this driver with CONFIG_SYS_I2C_TEGRA 1717 - This driver adds 4 i2c buses with a fix speed from 1718 100000 and the slave addr 0! 1719 1720 - drivers/i2c/ppc4xx_i2c.c 1721 - activate this driver with CONFIG_SYS_I2C_PPC4XX 1722 - CONFIG_SYS_I2C_PPC4XX_CH0 activate hardware channel 0 1723 - CONFIG_SYS_I2C_PPC4XX_CH1 activate hardware channel 1 1724 1725 - drivers/i2c/i2c_mxc.c 1726 - activate this driver with CONFIG_SYS_I2C_MXC 1727 - enable bus 1 with CONFIG_SYS_I2C_MXC_I2C1 1728 - enable bus 2 with CONFIG_SYS_I2C_MXC_I2C2 1729 - enable bus 3 with CONFIG_SYS_I2C_MXC_I2C3 1730 - enable bus 4 with CONFIG_SYS_I2C_MXC_I2C4 1731 - define speed for bus 1 with CONFIG_SYS_MXC_I2C1_SPEED 1732 - define slave for bus 1 with CONFIG_SYS_MXC_I2C1_SLAVE 1733 - define speed for bus 2 with CONFIG_SYS_MXC_I2C2_SPEED 1734 - define slave for bus 2 with CONFIG_SYS_MXC_I2C2_SLAVE 1735 - define speed for bus 3 with CONFIG_SYS_MXC_I2C3_SPEED 1736 - define slave for bus 3 with CONFIG_SYS_MXC_I2C3_SLAVE 1737 - define speed for bus 4 with CONFIG_SYS_MXC_I2C4_SPEED 1738 - define slave for bus 4 with CONFIG_SYS_MXC_I2C4_SLAVE 1739 If those defines are not set, default value is 100000 1740 for speed, and 0 for slave. 1741 1742 - drivers/i2c/rcar_i2c.c: 1743 - activate this driver with CONFIG_SYS_I2C_RCAR 1744 - This driver adds 4 i2c buses 1745 1746 - CONFIG_SYS_RCAR_I2C0_BASE for setting the register channel 0 1747 - CONFIG_SYS_RCAR_I2C0_SPEED for for the speed channel 0 1748 - CONFIG_SYS_RCAR_I2C1_BASE for setting the register channel 1 1749 - CONFIG_SYS_RCAR_I2C1_SPEED for for the speed channel 1 1750 - CONFIG_SYS_RCAR_I2C2_BASE for setting the register channel 2 1751 - CONFIG_SYS_RCAR_I2C2_SPEED for for the speed channel 2 1752 - CONFIG_SYS_RCAR_I2C3_BASE for setting the register channel 3 1753 - CONFIG_SYS_RCAR_I2C3_SPEED for for the speed channel 3 1754 - CONFIF_SYS_RCAR_I2C_NUM_CONTROLLERS for number of i2c buses 1755 1756 - drivers/i2c/sh_i2c.c: 1757 - activate this driver with CONFIG_SYS_I2C_SH 1758 - This driver adds from 2 to 5 i2c buses 1759 1760 - CONFIG_SYS_I2C_SH_BASE0 for setting the register channel 0 1761 - CONFIG_SYS_I2C_SH_SPEED0 for for the speed channel 0 1762 - CONFIG_SYS_I2C_SH_BASE1 for setting the register channel 1 1763 - CONFIG_SYS_I2C_SH_SPEED1 for for the speed channel 1 1764 - CONFIG_SYS_I2C_SH_BASE2 for setting the register channel 2 1765 - CONFIG_SYS_I2C_SH_SPEED2 for for the speed channel 2 1766 - CONFIG_SYS_I2C_SH_BASE3 for setting the register channel 3 1767 - CONFIG_SYS_I2C_SH_SPEED3 for for the speed channel 3 1768 - CONFIG_SYS_I2C_SH_BASE4 for setting the register channel 4 1769 - CONFIG_SYS_I2C_SH_SPEED4 for for the speed channel 4 1770 - CONFIG_SYS_I2C_SH_NUM_CONTROLLERS for number of i2c buses 1771 1772 - drivers/i2c/omap24xx_i2c.c 1773 - activate this driver with CONFIG_SYS_I2C_OMAP24XX 1774 - CONFIG_SYS_OMAP24_I2C_SPEED speed channel 0 1775 - CONFIG_SYS_OMAP24_I2C_SLAVE slave addr channel 0 1776 - CONFIG_SYS_OMAP24_I2C_SPEED1 speed channel 1 1777 - CONFIG_SYS_OMAP24_I2C_SLAVE1 slave addr channel 1 1778 - CONFIG_SYS_OMAP24_I2C_SPEED2 speed channel 2 1779 - CONFIG_SYS_OMAP24_I2C_SLAVE2 slave addr channel 2 1780 - CONFIG_SYS_OMAP24_I2C_SPEED3 speed channel 3 1781 - CONFIG_SYS_OMAP24_I2C_SLAVE3 slave addr channel 3 1782 - CONFIG_SYS_OMAP24_I2C_SPEED4 speed channel 4 1783 - CONFIG_SYS_OMAP24_I2C_SLAVE4 slave addr channel 4 1784 1785 - drivers/i2c/zynq_i2c.c 1786 - activate this driver with CONFIG_SYS_I2C_ZYNQ 1787 - set CONFIG_SYS_I2C_ZYNQ_SPEED for speed setting 1788 - set CONFIG_SYS_I2C_ZYNQ_SLAVE for slave addr 1789 1790 - drivers/i2c/s3c24x0_i2c.c: 1791 - activate this driver with CONFIG_SYS_I2C_S3C24X0 1792 - This driver adds i2c buses (11 for Exynos5250, Exynos5420 1793 9 i2c buses for Exynos4 and 1 for S3C24X0 SoCs from Samsung) 1794 with a fix speed from 100000 and the slave addr 0! 1795 1796 - drivers/i2c/ihs_i2c.c 1797 - activate this driver with CONFIG_SYS_I2C_IHS 1798 - CONFIG_SYS_I2C_IHS_CH0 activate hardware channel 0 1799 - CONFIG_SYS_I2C_IHS_SPEED_0 speed channel 0 1800 - CONFIG_SYS_I2C_IHS_SLAVE_0 slave addr channel 0 1801 - CONFIG_SYS_I2C_IHS_CH1 activate hardware channel 1 1802 - CONFIG_SYS_I2C_IHS_SPEED_1 speed channel 1 1803 - CONFIG_SYS_I2C_IHS_SLAVE_1 slave addr channel 1 1804 - CONFIG_SYS_I2C_IHS_CH2 activate hardware channel 2 1805 - CONFIG_SYS_I2C_IHS_SPEED_2 speed channel 2 1806 - CONFIG_SYS_I2C_IHS_SLAVE_2 slave addr channel 2 1807 - CONFIG_SYS_I2C_IHS_CH3 activate hardware channel 3 1808 - CONFIG_SYS_I2C_IHS_SPEED_3 speed channel 3 1809 - CONFIG_SYS_I2C_IHS_SLAVE_3 slave addr channel 3 1810 - activate dual channel with CONFIG_SYS_I2C_IHS_DUAL 1811 - CONFIG_SYS_I2C_IHS_SPEED_0_1 speed channel 0_1 1812 - CONFIG_SYS_I2C_IHS_SLAVE_0_1 slave addr channel 0_1 1813 - CONFIG_SYS_I2C_IHS_SPEED_1_1 speed channel 1_1 1814 - CONFIG_SYS_I2C_IHS_SLAVE_1_1 slave addr channel 1_1 1815 - CONFIG_SYS_I2C_IHS_SPEED_2_1 speed channel 2_1 1816 - CONFIG_SYS_I2C_IHS_SLAVE_2_1 slave addr channel 2_1 1817 - CONFIG_SYS_I2C_IHS_SPEED_3_1 speed channel 3_1 1818 - CONFIG_SYS_I2C_IHS_SLAVE_3_1 slave addr channel 3_1 1819 1820 additional defines: 1821 1822 CONFIG_SYS_NUM_I2C_BUSES 1823 Hold the number of i2c buses you want to use. 1824 1825 CONFIG_SYS_I2C_DIRECT_BUS 1826 define this, if you don't use i2c muxes on your hardware. 1827 if CONFIG_SYS_I2C_MAX_HOPS is not defined or == 0 you can 1828 omit this define. 1829 1830 CONFIG_SYS_I2C_MAX_HOPS 1831 define how many muxes are maximal consecutively connected 1832 on one i2c bus. If you not use i2c muxes, omit this 1833 define. 1834 1835 CONFIG_SYS_I2C_BUSES 1836 hold a list of buses you want to use, only used if 1837 CONFIG_SYS_I2C_DIRECT_BUS is not defined, for example 1838 a board with CONFIG_SYS_I2C_MAX_HOPS = 1 and 1839 CONFIG_SYS_NUM_I2C_BUSES = 9: 1840 1841 CONFIG_SYS_I2C_BUSES {{0, {I2C_NULL_HOP}}, \ 1842 {0, {{I2C_MUX_PCA9547, 0x70, 1}}}, \ 1843 {0, {{I2C_MUX_PCA9547, 0x70, 2}}}, \ 1844 {0, {{I2C_MUX_PCA9547, 0x70, 3}}}, \ 1845 {0, {{I2C_MUX_PCA9547, 0x70, 4}}}, \ 1846 {0, {{I2C_MUX_PCA9547, 0x70, 5}}}, \ 1847 {1, {I2C_NULL_HOP}}, \ 1848 {1, {{I2C_MUX_PCA9544, 0x72, 1}}}, \ 1849 {1, {{I2C_MUX_PCA9544, 0x72, 2}}}, \ 1850 } 1851 1852 which defines 1853 bus 0 on adapter 0 without a mux 1854 bus 1 on adapter 0 with a PCA9547 on address 0x70 port 1 1855 bus 2 on adapter 0 with a PCA9547 on address 0x70 port 2 1856 bus 3 on adapter 0 with a PCA9547 on address 0x70 port 3 1857 bus 4 on adapter 0 with a PCA9547 on address 0x70 port 4 1858 bus 5 on adapter 0 with a PCA9547 on address 0x70 port 5 1859 bus 6 on adapter 1 without a mux 1860 bus 7 on adapter 1 with a PCA9544 on address 0x72 port 1 1861 bus 8 on adapter 1 with a PCA9544 on address 0x72 port 2 1862 1863 If you do not have i2c muxes on your board, omit this define. 1864 1865- Legacy I2C Support: 1866 If you use the software i2c interface (CONFIG_SYS_I2C_SOFT) 1867 then the following macros need to be defined (examples are 1868 from include/configs/lwmon.h): 1869 1870 I2C_INIT 1871 1872 (Optional). Any commands necessary to enable the I2C 1873 controller or configure ports. 1874 1875 eg: #define I2C_INIT (immr->im_cpm.cp_pbdir |= PB_SCL) 1876 1877 I2C_ACTIVE 1878 1879 The code necessary to make the I2C data line active 1880 (driven). If the data line is open collector, this 1881 define can be null. 1882 1883 eg: #define I2C_ACTIVE (immr->im_cpm.cp_pbdir |= PB_SDA) 1884 1885 I2C_TRISTATE 1886 1887 The code necessary to make the I2C data line tri-stated 1888 (inactive). If the data line is open collector, this 1889 define can be null. 1890 1891 eg: #define I2C_TRISTATE (immr->im_cpm.cp_pbdir &= ~PB_SDA) 1892 1893 I2C_READ 1894 1895 Code that returns true if the I2C data line is high, 1896 false if it is low. 1897 1898 eg: #define I2C_READ ((immr->im_cpm.cp_pbdat & PB_SDA) != 0) 1899 1900 I2C_SDA(bit) 1901 1902 If <bit> is true, sets the I2C data line high. If it 1903 is false, it clears it (low). 1904 1905 eg: #define I2C_SDA(bit) \ 1906 if(bit) immr->im_cpm.cp_pbdat |= PB_SDA; \ 1907 else immr->im_cpm.cp_pbdat &= ~PB_SDA 1908 1909 I2C_SCL(bit) 1910 1911 If <bit> is true, sets the I2C clock line high. If it 1912 is false, it clears it (low). 1913 1914 eg: #define I2C_SCL(bit) \ 1915 if(bit) immr->im_cpm.cp_pbdat |= PB_SCL; \ 1916 else immr->im_cpm.cp_pbdat &= ~PB_SCL 1917 1918 I2C_DELAY 1919 1920 This delay is invoked four times per clock cycle so this 1921 controls the rate of data transfer. The data rate thus 1922 is 1 / (I2C_DELAY * 4). Often defined to be something 1923 like: 1924 1925 #define I2C_DELAY udelay(2) 1926 1927 CONFIG_SOFT_I2C_GPIO_SCL / CONFIG_SOFT_I2C_GPIO_SDA 1928 1929 If your arch supports the generic GPIO framework (asm/gpio.h), 1930 then you may alternatively define the two GPIOs that are to be 1931 used as SCL / SDA. Any of the previous I2C_xxx macros will 1932 have GPIO-based defaults assigned to them as appropriate. 1933 1934 You should define these to the GPIO value as given directly to 1935 the generic GPIO functions. 1936 1937 CONFIG_SYS_I2C_INIT_BOARD 1938 1939 When a board is reset during an i2c bus transfer 1940 chips might think that the current transfer is still 1941 in progress. On some boards it is possible to access 1942 the i2c SCLK line directly, either by using the 1943 processor pin as a GPIO or by having a second pin 1944 connected to the bus. If this option is defined a 1945 custom i2c_init_board() routine in boards/xxx/board.c 1946 is run early in the boot sequence. 1947 1948 CONFIG_I2C_MULTI_BUS 1949 1950 This option allows the use of multiple I2C buses, each of which 1951 must have a controller. At any point in time, only one bus is 1952 active. To switch to a different bus, use the 'i2c dev' command. 1953 Note that bus numbering is zero-based. 1954 1955 CONFIG_SYS_I2C_NOPROBES 1956 1957 This option specifies a list of I2C devices that will be skipped 1958 when the 'i2c probe' command is issued. If CONFIG_I2C_MULTI_BUS 1959 is set, specify a list of bus-device pairs. Otherwise, specify 1960 a 1D array of device addresses 1961 1962 e.g. 1963 #undef CONFIG_I2C_MULTI_BUS 1964 #define CONFIG_SYS_I2C_NOPROBES {0x50,0x68} 1965 1966 will skip addresses 0x50 and 0x68 on a board with one I2C bus 1967 1968 #define CONFIG_I2C_MULTI_BUS 1969 #define CONFIG_SYS_I2C_NOPROBES {{0,0x50},{0,0x68},{1,0x54}} 1970 1971 will skip addresses 0x50 and 0x68 on bus 0 and address 0x54 on bus 1 1972 1973 CONFIG_SYS_SPD_BUS_NUM 1974 1975 If defined, then this indicates the I2C bus number for DDR SPD. 1976 If not defined, then U-Boot assumes that SPD is on I2C bus 0. 1977 1978 CONFIG_SYS_RTC_BUS_NUM 1979 1980 If defined, then this indicates the I2C bus number for the RTC. 1981 If not defined, then U-Boot assumes that RTC is on I2C bus 0. 1982 1983 CONFIG_SOFT_I2C_READ_REPEATED_START 1984 1985 defining this will force the i2c_read() function in 1986 the soft_i2c driver to perform an I2C repeated start 1987 between writing the address pointer and reading the 1988 data. If this define is omitted the default behaviour 1989 of doing a stop-start sequence will be used. Most I2C 1990 devices can use either method, but some require one or 1991 the other. 1992 1993- SPI Support: CONFIG_SPI 1994 1995 Enables SPI driver (so far only tested with 1996 SPI EEPROM, also an instance works with Crystal A/D and 1997 D/As on the SACSng board) 1998 1999 CONFIG_SOFT_SPI 2000 2001 Enables a software (bit-bang) SPI driver rather than 2002 using hardware support. This is a general purpose 2003 driver that only requires three general I/O port pins 2004 (two outputs, one input) to function. If this is 2005 defined, the board configuration must define several 2006 SPI configuration items (port pins to use, etc). For 2007 an example, see include/configs/sacsng.h. 2008 2009 CONFIG_HARD_SPI 2010 2011 Enables a hardware SPI driver for general-purpose reads 2012 and writes. As with CONFIG_SOFT_SPI, the board configuration 2013 must define a list of chip-select function pointers. 2014 Currently supported on some MPC8xxx processors. For an 2015 example, see include/configs/mpc8349emds.h. 2016 2017 CONFIG_SYS_SPI_MXC_WAIT 2018 Timeout for waiting until spi transfer completed. 2019 default: (CONFIG_SYS_HZ/100) /* 10 ms */ 2020 2021- FPGA Support: CONFIG_FPGA 2022 2023 Enables FPGA subsystem. 2024 2025 CONFIG_FPGA_<vendor> 2026 2027 Enables support for specific chip vendors. 2028 (ALTERA, XILINX) 2029 2030 CONFIG_FPGA_<family> 2031 2032 Enables support for FPGA family. 2033 (SPARTAN2, SPARTAN3, VIRTEX2, CYCLONE2, ACEX1K, ACEX) 2034 2035 CONFIG_FPGA_COUNT 2036 2037 Specify the number of FPGA devices to support. 2038 2039 CONFIG_SYS_FPGA_PROG_FEEDBACK 2040 2041 Enable printing of hash marks during FPGA configuration. 2042 2043 CONFIG_SYS_FPGA_CHECK_BUSY 2044 2045 Enable checks on FPGA configuration interface busy 2046 status by the configuration function. This option 2047 will require a board or device specific function to 2048 be written. 2049 2050 CONFIG_FPGA_DELAY 2051 2052 If defined, a function that provides delays in the FPGA 2053 configuration driver. 2054 2055 CONFIG_SYS_FPGA_CHECK_CTRLC 2056 Allow Control-C to interrupt FPGA configuration 2057 2058 CONFIG_SYS_FPGA_CHECK_ERROR 2059 2060 Check for configuration errors during FPGA bitfile 2061 loading. For example, abort during Virtex II 2062 configuration if the INIT_B line goes low (which 2063 indicated a CRC error). 2064 2065 CONFIG_SYS_FPGA_WAIT_INIT 2066 2067 Maximum time to wait for the INIT_B line to de-assert 2068 after PROB_B has been de-asserted during a Virtex II 2069 FPGA configuration sequence. The default time is 500 2070 ms. 2071 2072 CONFIG_SYS_FPGA_WAIT_BUSY 2073 2074 Maximum time to wait for BUSY to de-assert during 2075 Virtex II FPGA configuration. The default is 5 ms. 2076 2077 CONFIG_SYS_FPGA_WAIT_CONFIG 2078 2079 Time to wait after FPGA configuration. The default is 2080 200 ms. 2081 2082- Configuration Management: 2083 CONFIG_BUILD_TARGET 2084 2085 Some SoCs need special image types (e.g. U-Boot binary 2086 with a special header) as build targets. By defining 2087 CONFIG_BUILD_TARGET in the SoC / board header, this 2088 special image will be automatically built upon calling 2089 make / buildman. 2090 2091 CONFIG_IDENT_STRING 2092 2093 If defined, this string will be added to the U-Boot 2094 version information (U_BOOT_VERSION) 2095 2096- Vendor Parameter Protection: 2097 2098 U-Boot considers the values of the environment 2099 variables "serial#" (Board Serial Number) and 2100 "ethaddr" (Ethernet Address) to be parameters that 2101 are set once by the board vendor / manufacturer, and 2102 protects these variables from casual modification by 2103 the user. Once set, these variables are read-only, 2104 and write or delete attempts are rejected. You can 2105 change this behaviour: 2106 2107 If CONFIG_ENV_OVERWRITE is #defined in your config 2108 file, the write protection for vendor parameters is 2109 completely disabled. Anybody can change or delete 2110 these parameters. 2111 2112 Alternatively, if you define _both_ an ethaddr in the 2113 default env _and_ CONFIG_OVERWRITE_ETHADDR_ONCE, a default 2114 Ethernet address is installed in the environment, 2115 which can be changed exactly ONCE by the user. [The 2116 serial# is unaffected by this, i. e. it remains 2117 read-only.] 2118 2119 The same can be accomplished in a more flexible way 2120 for any variable by configuring the type of access 2121 to allow for those variables in the ".flags" variable 2122 or define CONFIG_ENV_FLAGS_LIST_STATIC. 2123 2124- Protected RAM: 2125 CONFIG_PRAM 2126 2127 Define this variable to enable the reservation of 2128 "protected RAM", i. e. RAM which is not overwritten 2129 by U-Boot. Define CONFIG_PRAM to hold the number of 2130 kB you want to reserve for pRAM. You can overwrite 2131 this default value by defining an environment 2132 variable "pram" to the number of kB you want to 2133 reserve. Note that the board info structure will 2134 still show the full amount of RAM. If pRAM is 2135 reserved, a new environment variable "mem" will 2136 automatically be defined to hold the amount of 2137 remaining RAM in a form that can be passed as boot 2138 argument to Linux, for instance like that: 2139 2140 setenv bootargs ... mem=\${mem} 2141 saveenv 2142 2143 This way you can tell Linux not to use this memory, 2144 either, which results in a memory region that will 2145 not be affected by reboots. 2146 2147 *WARNING* If your board configuration uses automatic 2148 detection of the RAM size, you must make sure that 2149 this memory test is non-destructive. So far, the 2150 following board configurations are known to be 2151 "pRAM-clean": 2152 2153 IVMS8, IVML24, SPD8xx, 2154 HERMES, IP860, RPXlite, LWMON, 2155 FLAGADM 2156 2157- Access to physical memory region (> 4GB) 2158 Some basic support is provided for operations on memory not 2159 normally accessible to U-Boot - e.g. some architectures 2160 support access to more than 4GB of memory on 32-bit 2161 machines using physical address extension or similar. 2162 Define CONFIG_PHYSMEM to access this basic support, which 2163 currently only supports clearing the memory. 2164 2165- Error Recovery: 2166 CONFIG_NET_RETRY_COUNT 2167 2168 This variable defines the number of retries for 2169 network operations like ARP, RARP, TFTP, or BOOTP 2170 before giving up the operation. If not defined, a 2171 default value of 5 is used. 2172 2173 CONFIG_ARP_TIMEOUT 2174 2175 Timeout waiting for an ARP reply in milliseconds. 2176 2177 CONFIG_NFS_TIMEOUT 2178 2179 Timeout in milliseconds used in NFS protocol. 2180 If you encounter "ERROR: Cannot umount" in nfs command, 2181 try longer timeout such as 2182 #define CONFIG_NFS_TIMEOUT 10000UL 2183 2184- Command Interpreter: 2185 CONFIG_AUTO_COMPLETE 2186 2187 Enable auto completion of commands using TAB. 2188 2189 CONFIG_SYS_PROMPT_HUSH_PS2 2190 2191 This defines the secondary prompt string, which is 2192 printed when the command interpreter needs more input 2193 to complete a command. Usually "> ". 2194 2195 Note: 2196 2197 In the current implementation, the local variables 2198 space and global environment variables space are 2199 separated. Local variables are those you define by 2200 simply typing `name=value'. To access a local 2201 variable later on, you have write `$name' or 2202 `${name}'; to execute the contents of a variable 2203 directly type `$name' at the command prompt. 2204 2205 Global environment variables are those you use 2206 setenv/printenv to work with. To run a command stored 2207 in such a variable, you need to use the run command, 2208 and you must not use the '$' sign to access them. 2209 2210 To store commands and special characters in a 2211 variable, please use double quotation marks 2212 surrounding the whole text of the variable, instead 2213 of the backslashes before semicolons and special 2214 symbols. 2215 2216- Command Line Editing and History: 2217 CONFIG_CMDLINE_EDITING 2218 2219 Enable editing and History functions for interactive 2220 command line input operations 2221 2222- Command Line PS1/PS2 support: 2223 CONFIG_CMDLINE_PS_SUPPORT 2224 2225 Enable support for changing the command prompt string 2226 at run-time. Only static string is supported so far. 2227 The string is obtained from environment variables PS1 2228 and PS2. 2229 2230- Default Environment: 2231 CONFIG_EXTRA_ENV_SETTINGS 2232 2233 Define this to contain any number of null terminated 2234 strings (variable = value pairs) that will be part of 2235 the default environment compiled into the boot image. 2236 2237 For example, place something like this in your 2238 board's config file: 2239 2240 #define CONFIG_EXTRA_ENV_SETTINGS \ 2241 "myvar1=value1\0" \ 2242 "myvar2=value2\0" 2243 2244 Warning: This method is based on knowledge about the 2245 internal format how the environment is stored by the 2246 U-Boot code. This is NOT an official, exported 2247 interface! Although it is unlikely that this format 2248 will change soon, there is no guarantee either. 2249 You better know what you are doing here. 2250 2251 Note: overly (ab)use of the default environment is 2252 discouraged. Make sure to check other ways to preset 2253 the environment like the "source" command or the 2254 boot command first. 2255 2256 CONFIG_ENV_VARS_UBOOT_CONFIG 2257 2258 Define this in order to add variables describing the 2259 U-Boot build configuration to the default environment. 2260 These will be named arch, cpu, board, vendor, and soc. 2261 2262 Enabling this option will cause the following to be defined: 2263 2264 - CONFIG_SYS_ARCH 2265 - CONFIG_SYS_CPU 2266 - CONFIG_SYS_BOARD 2267 - CONFIG_SYS_VENDOR 2268 - CONFIG_SYS_SOC 2269 2270 CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG 2271 2272 Define this in order to add variables describing certain 2273 run-time determined information about the hardware to the 2274 environment. These will be named board_name, board_rev. 2275 2276 CONFIG_DELAY_ENVIRONMENT 2277 2278 Normally the environment is loaded when the board is 2279 initialised so that it is available to U-Boot. This inhibits 2280 that so that the environment is not available until 2281 explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL 2282 this is instead controlled by the value of 2283 /config/load-environment. 2284 2285- Serial Flash support 2286 Usage requires an initial 'sf probe' to define the serial 2287 flash parameters, followed by read/write/erase/update 2288 commands. 2289 2290 The following defaults may be provided by the platform 2291 to handle the common case when only a single serial 2292 flash is present on the system. 2293 2294 CONFIG_SF_DEFAULT_BUS Bus identifier 2295 CONFIG_SF_DEFAULT_CS Chip-select 2296 CONFIG_SF_DEFAULT_MODE (see include/spi.h) 2297 CONFIG_SF_DEFAULT_SPEED in Hz 2298 2299 2300- TFTP Fixed UDP Port: 2301 CONFIG_TFTP_PORT 2302 2303 If this is defined, the environment variable tftpsrcp 2304 is used to supply the TFTP UDP source port value. 2305 If tftpsrcp isn't defined, the normal pseudo-random port 2306 number generator is used. 2307 2308 Also, the environment variable tftpdstp is used to supply 2309 the TFTP UDP destination port value. If tftpdstp isn't 2310 defined, the normal port 69 is used. 2311 2312 The purpose for tftpsrcp is to allow a TFTP server to 2313 blindly start the TFTP transfer using the pre-configured 2314 target IP address and UDP port. This has the effect of 2315 "punching through" the (Windows XP) firewall, allowing 2316 the remainder of the TFTP transfer to proceed normally. 2317 A better solution is to properly configure the firewall, 2318 but sometimes that is not allowed. 2319 2320- bootcount support: 2321 CONFIG_AT91SAM9XE 2322 enable special bootcounter support on at91sam9xe based boards. 2323 CONFIG_SOC_DA8XX 2324 enable special bootcounter support on da850 based boards. 2325 CONFIG_BOOTCOUNT_RAM 2326 enable support for the bootcounter in RAM 2327 CONFIG_BOOTCOUNT_I2C 2328 enable support for the bootcounter on an i2c (like RTC) device. 2329 CONFIG_SYS_I2C_RTC_ADDR = i2c chip address 2330 CONFIG_SYS_BOOTCOUNT_ADDR = i2c addr which is used for 2331 the bootcounter. 2332 CONFIG_BOOTCOUNT_ALEN = address len 2333 CONFIG_BOOTCOUNT_EXT 2334 enable support for the bootcounter in EXT filesystem 2335 CONFIG_SYS_BOOTCOUNT_ADDR = RAM address used for read 2336 and write. 2337 CONFIG_SYS_BOOTCOUNT_EXT_INTERFACE = interface 2338 CONFIG_SYS_BOOTCOUNT_EXT_DEVPART = device and part 2339 CONFIG_SYS_BOOTCOUNT_EXT_NAME = filename 2340 2341- Show boot progress: 2342 CONFIG_SHOW_BOOT_PROGRESS 2343 2344 Defining this option allows to add some board- 2345 specific code (calling a user-provided function 2346 "show_boot_progress(int)") that enables you to show 2347 the system's boot progress on some display (for 2348 example, some LED's) on your board. At the moment, 2349 the following checkpoints are implemented: 2350 2351 2352Legacy uImage format: 2353 2354 Arg Where When 2355 1 common/cmd_bootm.c before attempting to boot an image 2356 -1 common/cmd_bootm.c Image header has bad magic number 2357 2 common/cmd_bootm.c Image header has correct magic number 2358 -2 common/cmd_bootm.c Image header has bad checksum 2359 3 common/cmd_bootm.c Image header has correct checksum 2360 -3 common/cmd_bootm.c Image data has bad checksum 2361 4 common/cmd_bootm.c Image data has correct checksum 2362 -4 common/cmd_bootm.c Image is for unsupported architecture 2363 5 common/cmd_bootm.c Architecture check OK 2364 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi) 2365 6 common/cmd_bootm.c Image Type check OK 2366 -6 common/cmd_bootm.c gunzip uncompression error 2367 -7 common/cmd_bootm.c Unimplemented compression type 2368 7 common/cmd_bootm.c Uncompression OK 2369 8 common/cmd_bootm.c No uncompress/copy overwrite error 2370 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX) 2371 2372 9 common/image.c Start initial ramdisk verification 2373 -10 common/image.c Ramdisk header has bad magic number 2374 -11 common/image.c Ramdisk header has bad checksum 2375 10 common/image.c Ramdisk header is OK 2376 -12 common/image.c Ramdisk data has bad checksum 2377 11 common/image.c Ramdisk data has correct checksum 2378 12 common/image.c Ramdisk verification complete, start loading 2379 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk) 2380 13 common/image.c Start multifile image verification 2381 14 common/image.c No initial ramdisk, no multifile, continue. 2382 2383 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS 2384 2385 -30 arch/powerpc/lib/board.c Fatal error, hang the system 2386 -31 post/post.c POST test failed, detected by post_output_backlog() 2387 -32 post/post.c POST test failed, detected by post_run_single() 2388 2389 34 common/cmd_doc.c before loading a Image from a DOC device 2390 -35 common/cmd_doc.c Bad usage of "doc" command 2391 35 common/cmd_doc.c correct usage of "doc" command 2392 -36 common/cmd_doc.c No boot device 2393 36 common/cmd_doc.c correct boot device 2394 -37 common/cmd_doc.c Unknown Chip ID on boot device 2395 37 common/cmd_doc.c correct chip ID found, device available 2396 -38 common/cmd_doc.c Read Error on boot device 2397 38 common/cmd_doc.c reading Image header from DOC device OK 2398 -39 common/cmd_doc.c Image header has bad magic number 2399 39 common/cmd_doc.c Image header has correct magic number 2400 -40 common/cmd_doc.c Error reading Image from DOC device 2401 40 common/cmd_doc.c Image header has correct magic number 2402 41 common/cmd_ide.c before loading a Image from a IDE device 2403 -42 common/cmd_ide.c Bad usage of "ide" command 2404 42 common/cmd_ide.c correct usage of "ide" command 2405 -43 common/cmd_ide.c No boot device 2406 43 common/cmd_ide.c boot device found 2407 -44 common/cmd_ide.c Device not available 2408 44 common/cmd_ide.c Device available 2409 -45 common/cmd_ide.c wrong partition selected 2410 45 common/cmd_ide.c partition selected 2411 -46 common/cmd_ide.c Unknown partition table 2412 46 common/cmd_ide.c valid partition table found 2413 -47 common/cmd_ide.c Invalid partition type 2414 47 common/cmd_ide.c correct partition type 2415 -48 common/cmd_ide.c Error reading Image Header on boot device 2416 48 common/cmd_ide.c reading Image Header from IDE device OK 2417 -49 common/cmd_ide.c Image header has bad magic number 2418 49 common/cmd_ide.c Image header has correct magic number 2419 -50 common/cmd_ide.c Image header has bad checksum 2420 50 common/cmd_ide.c Image header has correct checksum 2421 -51 common/cmd_ide.c Error reading Image from IDE device 2422 51 common/cmd_ide.c reading Image from IDE device OK 2423 52 common/cmd_nand.c before loading a Image from a NAND device 2424 -53 common/cmd_nand.c Bad usage of "nand" command 2425 53 common/cmd_nand.c correct usage of "nand" command 2426 -54 common/cmd_nand.c No boot device 2427 54 common/cmd_nand.c boot device found 2428 -55 common/cmd_nand.c Unknown Chip ID on boot device 2429 55 common/cmd_nand.c correct chip ID found, device available 2430 -56 common/cmd_nand.c Error reading Image Header on boot device 2431 56 common/cmd_nand.c reading Image Header from NAND device OK 2432 -57 common/cmd_nand.c Image header has bad magic number 2433 57 common/cmd_nand.c Image header has correct magic number 2434 -58 common/cmd_nand.c Error reading Image from NAND device 2435 58 common/cmd_nand.c reading Image from NAND device OK 2436 2437 -60 common/env_common.c Environment has a bad CRC, using default 2438 2439 64 net/eth.c starting with Ethernet configuration. 2440 -64 net/eth.c no Ethernet found. 2441 65 net/eth.c Ethernet found. 2442 2443 -80 common/cmd_net.c usage wrong 2444 80 common/cmd_net.c before calling net_loop() 2445 -81 common/cmd_net.c some error in net_loop() occurred 2446 81 common/cmd_net.c net_loop() back without error 2447 -82 common/cmd_net.c size == 0 (File with size 0 loaded) 2448 82 common/cmd_net.c trying automatic boot 2449 83 common/cmd_net.c running "source" command 2450 -83 common/cmd_net.c some error in automatic boot or "source" command 2451 84 common/cmd_net.c end without errors 2452 2453FIT uImage format: 2454 2455 Arg Where When 2456 100 common/cmd_bootm.c Kernel FIT Image has correct format 2457 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format 2458 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration 2459 -101 common/cmd_bootm.c Can't get configuration for kernel subimage 2460 102 common/cmd_bootm.c Kernel unit name specified 2461 -103 common/cmd_bootm.c Can't get kernel subimage node offset 2462 103 common/cmd_bootm.c Found configuration node 2463 104 common/cmd_bootm.c Got kernel subimage node offset 2464 -104 common/cmd_bootm.c Kernel subimage hash verification failed 2465 105 common/cmd_bootm.c Kernel subimage hash verification OK 2466 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture 2467 106 common/cmd_bootm.c Architecture check OK 2468 -106 common/cmd_bootm.c Kernel subimage has wrong type 2469 107 common/cmd_bootm.c Kernel subimage type OK 2470 -107 common/cmd_bootm.c Can't get kernel subimage data/size 2471 108 common/cmd_bootm.c Got kernel subimage data/size 2472 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT) 2473 -109 common/cmd_bootm.c Can't get kernel subimage type 2474 -110 common/cmd_bootm.c Can't get kernel subimage comp 2475 -111 common/cmd_bootm.c Can't get kernel subimage os 2476 -112 common/cmd_bootm.c Can't get kernel subimage load address 2477 -113 common/cmd_bootm.c Image uncompress/copy overwrite error 2478 2479 120 common/image.c Start initial ramdisk verification 2480 -120 common/image.c Ramdisk FIT image has incorrect format 2481 121 common/image.c Ramdisk FIT image has correct format 2482 122 common/image.c No ramdisk subimage unit name, using configuration 2483 -122 common/image.c Can't get configuration for ramdisk subimage 2484 123 common/image.c Ramdisk unit name specified 2485 -124 common/image.c Can't get ramdisk subimage node offset 2486 125 common/image.c Got ramdisk subimage node offset 2487 -125 common/image.c Ramdisk subimage hash verification failed 2488 126 common/image.c Ramdisk subimage hash verification OK 2489 -126 common/image.c Ramdisk subimage for unsupported architecture 2490 127 common/image.c Architecture check OK 2491 -127 common/image.c Can't get ramdisk subimage data/size 2492 128 common/image.c Got ramdisk subimage data/size 2493 129 common/image.c Can't get ramdisk load address 2494 -129 common/image.c Got ramdisk load address 2495 2496 -130 common/cmd_doc.c Incorrect FIT image format 2497 131 common/cmd_doc.c FIT image format OK 2498 2499 -140 common/cmd_ide.c Incorrect FIT image format 2500 141 common/cmd_ide.c FIT image format OK 2501 2502 -150 common/cmd_nand.c Incorrect FIT image format 2503 151 common/cmd_nand.c FIT image format OK 2504 2505- legacy image format: 2506 CONFIG_IMAGE_FORMAT_LEGACY 2507 enables the legacy image format support in U-Boot. 2508 2509 Default: 2510 enabled if CONFIG_FIT_SIGNATURE is not defined. 2511 2512 CONFIG_DISABLE_IMAGE_LEGACY 2513 disable the legacy image format 2514 2515 This define is introduced, as the legacy image format is 2516 enabled per default for backward compatibility. 2517 2518- Standalone program support: 2519 CONFIG_STANDALONE_LOAD_ADDR 2520 2521 This option defines a board specific value for the 2522 address where standalone program gets loaded, thus 2523 overwriting the architecture dependent default 2524 settings. 2525 2526- Frame Buffer Address: 2527 CONFIG_FB_ADDR 2528 2529 Define CONFIG_FB_ADDR if you want to use specific 2530 address for frame buffer. This is typically the case 2531 when using a graphics controller has separate video 2532 memory. U-Boot will then place the frame buffer at 2533 the given address instead of dynamically reserving it 2534 in system RAM by calling lcd_setmem(), which grabs 2535 the memory for the frame buffer depending on the 2536 configured panel size. 2537 2538 Please see board_init_f function. 2539 2540- Automatic software updates via TFTP server 2541 CONFIG_UPDATE_TFTP 2542 CONFIG_UPDATE_TFTP_CNT_MAX 2543 CONFIG_UPDATE_TFTP_MSEC_MAX 2544 2545 These options enable and control the auto-update feature; 2546 for a more detailed description refer to doc/README.update. 2547 2548- MTD Support (mtdparts command, UBI support) 2549 CONFIG_MTD_DEVICE 2550 2551 Adds the MTD device infrastructure from the Linux kernel. 2552 Needed for mtdparts command support. 2553 2554 CONFIG_MTD_PARTITIONS 2555 2556 Adds the MTD partitioning infrastructure from the Linux 2557 kernel. Needed for UBI support. 2558 2559- UBI support 2560 CONFIG_UBI_SILENCE_MSG 2561 2562 Make the verbose messages from UBI stop printing. This leaves 2563 warnings and errors enabled. 2564 2565 2566 CONFIG_MTD_UBI_WL_THRESHOLD 2567 This parameter defines the maximum difference between the highest 2568 erase counter value and the lowest erase counter value of eraseblocks 2569 of UBI devices. When this threshold is exceeded, UBI starts performing 2570 wear leveling by means of moving data from eraseblock with low erase 2571 counter to eraseblocks with high erase counter. 2572 2573 The default value should be OK for SLC NAND flashes, NOR flashes and 2574 other flashes which have eraseblock life-cycle 100000 or more. 2575 However, in case of MLC NAND flashes which typically have eraseblock 2576 life-cycle less than 10000, the threshold should be lessened (e.g., 2577 to 128 or 256, although it does not have to be power of 2). 2578 2579 default: 4096 2580 2581 CONFIG_MTD_UBI_BEB_LIMIT 2582 This option specifies the maximum bad physical eraseblocks UBI 2583 expects on the MTD device (per 1024 eraseblocks). If the 2584 underlying flash does not admit of bad eraseblocks (e.g. NOR 2585 flash), this value is ignored. 2586 2587 NAND datasheets often specify the minimum and maximum NVM 2588 (Number of Valid Blocks) for the flashes' endurance lifetime. 2589 The maximum expected bad eraseblocks per 1024 eraseblocks 2590 then can be calculated as "1024 * (1 - MinNVB / MaxNVB)", 2591 which gives 20 for most NANDs (MaxNVB is basically the total 2592 count of eraseblocks on the chip). 2593 2594 To put it differently, if this value is 20, UBI will try to 2595 reserve about 1.9% of physical eraseblocks for bad blocks 2596 handling. And that will be 1.9% of eraseblocks on the entire 2597 NAND chip, not just the MTD partition UBI attaches. This means 2598 that if you have, say, a NAND flash chip admits maximum 40 bad 2599 eraseblocks, and it is split on two MTD partitions of the same 2600 size, UBI will reserve 40 eraseblocks when attaching a 2601 partition. 2602 2603 default: 20 2604 2605 CONFIG_MTD_UBI_FASTMAP 2606 Fastmap is a mechanism which allows attaching an UBI device 2607 in nearly constant time. Instead of scanning the whole MTD device it 2608 only has to locate a checkpoint (called fastmap) on the device. 2609 The on-flash fastmap contains all information needed to attach 2610 the device. Using fastmap makes only sense on large devices where 2611 attaching by scanning takes long. UBI will not automatically install 2612 a fastmap on old images, but you can set the UBI parameter 2613 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT to 1 if you want so. Please note 2614 that fastmap-enabled images are still usable with UBI implementations 2615 without fastmap support. On typical flash devices the whole fastmap 2616 fits into one PEB. UBI will reserve PEBs to hold two fastmaps. 2617 2618 CONFIG_MTD_UBI_FASTMAP_AUTOCONVERT 2619 Set this parameter to enable fastmap automatically on images 2620 without a fastmap. 2621 default: 0 2622 2623 CONFIG_MTD_UBI_FM_DEBUG 2624 Enable UBI fastmap debug 2625 default: 0 2626 2627- UBIFS support 2628 CONFIG_UBIFS_SILENCE_MSG 2629 2630 Make the verbose messages from UBIFS stop printing. This leaves 2631 warnings and errors enabled. 2632 2633- SPL framework 2634 CONFIG_SPL 2635 Enable building of SPL globally. 2636 2637 CONFIG_SPL_LDSCRIPT 2638 LDSCRIPT for linking the SPL binary. 2639 2640 CONFIG_SPL_MAX_FOOTPRINT 2641 Maximum size in memory allocated to the SPL, BSS included. 2642 When defined, the linker checks that the actual memory 2643 used by SPL from _start to __bss_end does not exceed it. 2644 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 2645 must not be both defined at the same time. 2646 2647 CONFIG_SPL_MAX_SIZE 2648 Maximum size of the SPL image (text, data, rodata, and 2649 linker lists sections), BSS excluded. 2650 When defined, the linker checks that the actual size does 2651 not exceed it. 2652 2653 CONFIG_SPL_TEXT_BASE 2654 TEXT_BASE for linking the SPL binary. 2655 2656 CONFIG_SPL_RELOC_TEXT_BASE 2657 Address to relocate to. If unspecified, this is equal to 2658 CONFIG_SPL_TEXT_BASE (i.e. no relocation is done). 2659 2660 CONFIG_SPL_BSS_START_ADDR 2661 Link address for the BSS within the SPL binary. 2662 2663 CONFIG_SPL_BSS_MAX_SIZE 2664 Maximum size in memory allocated to the SPL BSS. 2665 When defined, the linker checks that the actual memory used 2666 by SPL from __bss_start to __bss_end does not exceed it. 2667 CONFIG_SPL_MAX_FOOTPRINT and CONFIG_SPL_BSS_MAX_SIZE 2668 must not be both defined at the same time. 2669 2670 CONFIG_SPL_STACK 2671 Adress of the start of the stack SPL will use 2672 2673 CONFIG_SPL_PANIC_ON_RAW_IMAGE 2674 When defined, SPL will panic() if the image it has 2675 loaded does not have a signature. 2676 Defining this is useful when code which loads images 2677 in SPL cannot guarantee that absolutely all read errors 2678 will be caught. 2679 An example is the LPC32XX MLC NAND driver, which will 2680 consider that a completely unreadable NAND block is bad, 2681 and thus should be skipped silently. 2682 2683 CONFIG_SPL_RELOC_STACK 2684 Adress of the start of the stack SPL will use after 2685 relocation. If unspecified, this is equal to 2686 CONFIG_SPL_STACK. 2687 2688 CONFIG_SYS_SPL_MALLOC_START 2689 Starting address of the malloc pool used in SPL. 2690 When this option is set the full malloc is used in SPL and 2691 it is set up by spl_init() and before that, the simple malloc() 2692 can be used if CONFIG_SYS_MALLOC_F is defined. 2693 2694 CONFIG_SYS_SPL_MALLOC_SIZE 2695 The size of the malloc pool used in SPL. 2696 2697 CONFIG_SPL_OS_BOOT 2698 Enable booting directly to an OS from SPL. 2699 See also: doc/README.falcon 2700 2701 CONFIG_SPL_DISPLAY_PRINT 2702 For ARM, enable an optional function to print more information 2703 about the running system. 2704 2705 CONFIG_SPL_INIT_MINIMAL 2706 Arch init code should be built for a very small image 2707 2708 CONFIG_SYS_MMCSD_RAW_MODE_U_BOOT_PARTITION 2709 Partition on the MMC to load U-Boot from when the MMC is being 2710 used in raw mode 2711 2712 CONFIG_SYS_MMCSD_RAW_MODE_KERNEL_SECTOR 2713 Sector to load kernel uImage from when MMC is being 2714 used in raw mode (for Falcon mode) 2715 2716 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTOR, 2717 CONFIG_SYS_MMCSD_RAW_MODE_ARGS_SECTORS 2718 Sector and number of sectors to load kernel argument 2719 parameters from when MMC is being used in raw mode 2720 (for falcon mode) 2721 2722 CONFIG_SYS_MMCSD_FS_BOOT_PARTITION 2723 Partition on the MMC to load U-Boot from when the MMC is being 2724 used in fs mode 2725 2726 CONFIG_SPL_FS_LOAD_PAYLOAD_NAME 2727 Filename to read to load U-Boot when reading from filesystem 2728 2729 CONFIG_SPL_FS_LOAD_KERNEL_NAME 2730 Filename to read to load kernel uImage when reading 2731 from filesystem (for Falcon mode) 2732 2733 CONFIG_SPL_FS_LOAD_ARGS_NAME 2734 Filename to read to load kernel argument parameters 2735 when reading from filesystem (for Falcon mode) 2736 2737 CONFIG_SPL_MPC83XX_WAIT_FOR_NAND 2738 Set this for NAND SPL on PPC mpc83xx targets, so that 2739 start.S waits for the rest of the SPL to load before 2740 continuing (the hardware starts execution after just 2741 loading the first page rather than the full 4K). 2742 2743 CONFIG_SPL_SKIP_RELOCATE 2744 Avoid SPL relocation 2745 2746 CONFIG_SPL_NAND_BASE 2747 Include nand_base.c in the SPL. Requires 2748 CONFIG_SPL_NAND_DRIVERS. 2749 2750 CONFIG_SPL_NAND_DRIVERS 2751 SPL uses normal NAND drivers, not minimal drivers. 2752 2753 CONFIG_SPL_NAND_ECC 2754 Include standard software ECC in the SPL 2755 2756 CONFIG_SPL_NAND_SIMPLE 2757 Support for NAND boot using simple NAND drivers that 2758 expose the cmd_ctrl() interface. 2759 2760 CONFIG_SPL_UBI 2761 Support for a lightweight UBI (fastmap) scanner and 2762 loader 2763 2764 CONFIG_SPL_NAND_RAW_ONLY 2765 Support to boot only raw u-boot.bin images. Use this only 2766 if you need to save space. 2767 2768 CONFIG_SPL_COMMON_INIT_DDR 2769 Set for common ddr init with serial presence detect in 2770 SPL binary. 2771 2772 CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT, 2773 CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE, 2774 CONFIG_SYS_NAND_BLOCK_SIZE, CONFIG_SYS_NAND_BAD_BLOCK_POS, 2775 CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE, 2776 CONFIG_SYS_NAND_ECCBYTES 2777 Defines the size and behavior of the NAND that SPL uses 2778 to read U-Boot 2779 2780 CONFIG_SPL_NAND_BOOT 2781 Add support NAND boot 2782 2783 CONFIG_SYS_NAND_U_BOOT_OFFS 2784 Location in NAND to read U-Boot from 2785 2786 CONFIG_SYS_NAND_U_BOOT_DST 2787 Location in memory to load U-Boot to 2788 2789 CONFIG_SYS_NAND_U_BOOT_SIZE 2790 Size of image to load 2791 2792 CONFIG_SYS_NAND_U_BOOT_START 2793 Entry point in loaded image to jump to 2794 2795 CONFIG_SYS_NAND_HW_ECC_OOBFIRST 2796 Define this if you need to first read the OOB and then the 2797 data. This is used, for example, on davinci platforms. 2798 2799 CONFIG_SPL_RAM_DEVICE 2800 Support for running image already present in ram, in SPL binary 2801 2802 CONFIG_SPL_PAD_TO 2803 Image offset to which the SPL should be padded before appending 2804 the SPL payload. By default, this is defined as 2805 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 2806 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 2807 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 2808 2809 CONFIG_SPL_TARGET 2810 Final target image containing SPL and payload. Some SPLs 2811 use an arch-specific makefile fragment instead, for 2812 example if more than one image needs to be produced. 2813 2814 CONFIG_FIT_SPL_PRINT 2815 Printing information about a FIT image adds quite a bit of 2816 code to SPL. So this is normally disabled in SPL. Use this 2817 option to re-enable it. This will affect the output of the 2818 bootm command when booting a FIT image. 2819 2820- TPL framework 2821 CONFIG_TPL 2822 Enable building of TPL globally. 2823 2824 CONFIG_TPL_PAD_TO 2825 Image offset to which the TPL should be padded before appending 2826 the TPL payload. By default, this is defined as 2827 CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined. 2828 CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL 2829 payload without any padding, or >= CONFIG_SPL_MAX_SIZE. 2830 2831- Interrupt support (PPC): 2832 2833 There are common interrupt_init() and timer_interrupt() 2834 for all PPC archs. interrupt_init() calls interrupt_init_cpu() 2835 for CPU specific initialization. interrupt_init_cpu() 2836 should set decrementer_count to appropriate value. If 2837 CPU resets decrementer automatically after interrupt 2838 (ppc4xx) it should set decrementer_count to zero. 2839 timer_interrupt() calls timer_interrupt_cpu() for CPU 2840 specific handling. If board has watchdog / status_led 2841 / other_activity_monitor it works automatically from 2842 general timer_interrupt(). 2843 2844 2845Board initialization settings: 2846------------------------------ 2847 2848During Initialization u-boot calls a number of board specific functions 2849to allow the preparation of board specific prerequisites, e.g. pin setup 2850before drivers are initialized. To enable these callbacks the 2851following configuration macros have to be defined. Currently this is 2852architecture specific, so please check arch/your_architecture/lib/board.c 2853typically in board_init_f() and board_init_r(). 2854 2855- CONFIG_BOARD_EARLY_INIT_F: Call board_early_init_f() 2856- CONFIG_BOARD_EARLY_INIT_R: Call board_early_init_r() 2857- CONFIG_BOARD_LATE_INIT: Call board_late_init() 2858- CONFIG_BOARD_POSTCLK_INIT: Call board_postclk_init() 2859 2860Configuration Settings: 2861----------------------- 2862 2863- CONFIG_SYS_SUPPORT_64BIT_DATA: Defined automatically if compiled as 64-bit. 2864 Optionally it can be defined to support 64-bit memory commands. 2865 2866- CONFIG_SYS_LONGHELP: Defined when you want long help messages included; 2867 undefine this when you're short of memory. 2868 2869- CONFIG_SYS_HELP_CMD_WIDTH: Defined when you want to override the default 2870 width of the commands listed in the 'help' command output. 2871 2872- CONFIG_SYS_PROMPT: This is what U-Boot prints on the console to 2873 prompt for user input. 2874 2875- CONFIG_SYS_CBSIZE: Buffer size for input from the Console 2876 2877- CONFIG_SYS_PBSIZE: Buffer size for Console output 2878 2879- CONFIG_SYS_MAXARGS: max. Number of arguments accepted for monitor commands 2880 2881- CONFIG_SYS_BARGSIZE: Buffer size for Boot Arguments which are passed to 2882 the application (usually a Linux kernel) when it is 2883 booted 2884 2885- CONFIG_SYS_BAUDRATE_TABLE: 2886 List of legal baudrate settings for this board. 2887 2888- CONFIG_SYS_MEMTEST_START, CONFIG_SYS_MEMTEST_END: 2889 Begin and End addresses of the area used by the 2890 simple memory test. 2891 2892- CONFIG_SYS_ALT_MEMTEST: 2893 Enable an alternate, more extensive memory test. 2894 2895- CONFIG_SYS_MEMTEST_SCRATCH: 2896 Scratch address used by the alternate memory test 2897 You only need to set this if address zero isn't writeable 2898 2899- CONFIG_SYS_MEM_RESERVE_SECURE 2900 Only implemented for ARMv8 for now. 2901 If defined, the size of CONFIG_SYS_MEM_RESERVE_SECURE memory 2902 is substracted from total RAM and won't be reported to OS. 2903 This memory can be used as secure memory. A variable 2904 gd->arch.secure_ram is used to track the location. In systems 2905 the RAM base is not zero, or RAM is divided into banks, 2906 this variable needs to be recalcuated to get the address. 2907 2908- CONFIG_SYS_MEM_TOP_HIDE: 2909 If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header, 2910 this specified memory area will get subtracted from the top 2911 (end) of RAM and won't get "touched" at all by U-Boot. By 2912 fixing up gd->ram_size the Linux kernel should gets passed 2913 the now "corrected" memory size and won't touch it either. 2914 This should work for arch/ppc and arch/powerpc. Only Linux 2915 board ports in arch/powerpc with bootwrapper support that 2916 recalculate the memory size from the SDRAM controller setup 2917 will have to get fixed in Linux additionally. 2918 2919 This option can be used as a workaround for the 440EPx/GRx 2920 CHIP 11 errata where the last 256 bytes in SDRAM shouldn't 2921 be touched. 2922 2923 WARNING: Please make sure that this value is a multiple of 2924 the Linux page size (normally 4k). If this is not the case, 2925 then the end address of the Linux memory will be located at a 2926 non page size aligned address and this could cause major 2927 problems. 2928 2929- CONFIG_SYS_LOADS_BAUD_CHANGE: 2930 Enable temporary baudrate change while serial download 2931 2932- CONFIG_SYS_SDRAM_BASE: 2933 Physical start address of SDRAM. _Must_ be 0 here. 2934 2935- CONFIG_SYS_FLASH_BASE: 2936 Physical start address of Flash memory. 2937 2938- CONFIG_SYS_MONITOR_BASE: 2939 Physical start address of boot monitor code (set by 2940 make config files to be same as the text base address 2941 (CONFIG_SYS_TEXT_BASE) used when linking) - same as 2942 CONFIG_SYS_FLASH_BASE when booting from flash. 2943 2944- CONFIG_SYS_MONITOR_LEN: 2945 Size of memory reserved for monitor code, used to 2946 determine _at_compile_time_ (!) if the environment is 2947 embedded within the U-Boot image, or in a separate 2948 flash sector. 2949 2950- CONFIG_SYS_MALLOC_LEN: 2951 Size of DRAM reserved for malloc() use. 2952 2953- CONFIG_SYS_MALLOC_F_LEN 2954 Size of the malloc() pool for use before relocation. If 2955 this is defined, then a very simple malloc() implementation 2956 will become available before relocation. The address is just 2957 below the global data, and the stack is moved down to make 2958 space. 2959 2960 This feature allocates regions with increasing addresses 2961 within the region. calloc() is supported, but realloc() 2962 is not available. free() is supported but does nothing. 2963 The memory will be freed (or in fact just forgotten) when 2964 U-Boot relocates itself. 2965 2966- CONFIG_SYS_MALLOC_SIMPLE 2967 Provides a simple and small malloc() and calloc() for those 2968 boards which do not use the full malloc in SPL (which is 2969 enabled with CONFIG_SYS_SPL_MALLOC_START). 2970 2971- CONFIG_SYS_NONCACHED_MEMORY: 2972 Size of non-cached memory area. This area of memory will be 2973 typically located right below the malloc() area and mapped 2974 uncached in the MMU. This is useful for drivers that would 2975 otherwise require a lot of explicit cache maintenance. For 2976 some drivers it's also impossible to properly maintain the 2977 cache. For example if the regions that need to be flushed 2978 are not a multiple of the cache-line size, *and* padding 2979 cannot be allocated between the regions to align them (i.e. 2980 if the HW requires a contiguous array of regions, and the 2981 size of each region is not cache-aligned), then a flush of 2982 one region may result in overwriting data that hardware has 2983 written to another region in the same cache-line. This can 2984 happen for example in network drivers where descriptors for 2985 buffers are typically smaller than the CPU cache-line (e.g. 2986 16 bytes vs. 32 or 64 bytes). 2987 2988 Non-cached memory is only supported on 32-bit ARM at present. 2989 2990- CONFIG_SYS_BOOTM_LEN: 2991 Normally compressed uImages are limited to an 2992 uncompressed size of 8 MBytes. If this is not enough, 2993 you can define CONFIG_SYS_BOOTM_LEN in your board config file 2994 to adjust this setting to your needs. 2995 2996- CONFIG_SYS_BOOTMAPSZ: 2997 Maximum size of memory mapped by the startup code of 2998 the Linux kernel; all data that must be processed by 2999 the Linux kernel (bd_info, boot arguments, FDT blob if 3000 used) must be put below this limit, unless "bootm_low" 3001 environment variable is defined and non-zero. In such case 3002 all data for the Linux kernel must be between "bootm_low" 3003 and "bootm_low" + CONFIG_SYS_BOOTMAPSZ. The environment 3004 variable "bootm_mapsize" will override the value of 3005 CONFIG_SYS_BOOTMAPSZ. If CONFIG_SYS_BOOTMAPSZ is undefined, 3006 then the value in "bootm_size" will be used instead. 3007 3008- CONFIG_SYS_BOOT_RAMDISK_HIGH: 3009 Enable initrd_high functionality. If defined then the 3010 initrd_high feature is enabled and the bootm ramdisk subcommand 3011 is enabled. 3012 3013- CONFIG_SYS_BOOT_GET_CMDLINE: 3014 Enables allocating and saving kernel cmdline in space between 3015 "bootm_low" and "bootm_low" + BOOTMAPSZ. 3016 3017- CONFIG_SYS_BOOT_GET_KBD: 3018 Enables allocating and saving a kernel copy of the bd_info in 3019 space between "bootm_low" and "bootm_low" + BOOTMAPSZ. 3020 3021- CONFIG_SYS_MAX_FLASH_BANKS: 3022 Max number of Flash memory banks 3023 3024- CONFIG_SYS_MAX_FLASH_SECT: 3025 Max number of sectors on a Flash chip 3026 3027- CONFIG_SYS_FLASH_ERASE_TOUT: 3028 Timeout for Flash erase operations (in ms) 3029 3030- CONFIG_SYS_FLASH_WRITE_TOUT: 3031 Timeout for Flash write operations (in ms) 3032 3033- CONFIG_SYS_FLASH_LOCK_TOUT 3034 Timeout for Flash set sector lock bit operation (in ms) 3035 3036- CONFIG_SYS_FLASH_UNLOCK_TOUT 3037 Timeout for Flash clear lock bits operation (in ms) 3038 3039- CONFIG_SYS_FLASH_PROTECTION 3040 If defined, hardware flash sectors protection is used 3041 instead of U-Boot software protection. 3042 3043- CONFIG_SYS_DIRECT_FLASH_TFTP: 3044 3045 Enable TFTP transfers directly to flash memory; 3046 without this option such a download has to be 3047 performed in two steps: (1) download to RAM, and (2) 3048 copy from RAM to flash. 3049 3050 The two-step approach is usually more reliable, since 3051 you can check if the download worked before you erase 3052 the flash, but in some situations (when system RAM is 3053 too limited to allow for a temporary copy of the 3054 downloaded image) this option may be very useful. 3055 3056- CONFIG_SYS_FLASH_CFI: 3057 Define if the flash driver uses extra elements in the 3058 common flash structure for storing flash geometry. 3059 3060- CONFIG_FLASH_CFI_DRIVER 3061 This option also enables the building of the cfi_flash driver 3062 in the drivers directory 3063 3064- CONFIG_FLASH_CFI_MTD 3065 This option enables the building of the cfi_mtd driver 3066 in the drivers directory. The driver exports CFI flash 3067 to the MTD layer. 3068 3069- CONFIG_SYS_FLASH_USE_BUFFER_WRITE 3070 Use buffered writes to flash. 3071 3072- CONFIG_FLASH_SPANSION_S29WS_N 3073 s29ws-n MirrorBit flash has non-standard addresses for buffered 3074 write commands. 3075 3076- CONFIG_SYS_FLASH_QUIET_TEST 3077 If this option is defined, the common CFI flash doesn't 3078 print it's warning upon not recognized FLASH banks. This 3079 is useful, if some of the configured banks are only 3080 optionally available. 3081 3082- CONFIG_FLASH_SHOW_PROGRESS 3083 If defined (must be an integer), print out countdown 3084 digits and dots. Recommended value: 45 (9..1) for 80 3085 column displays, 15 (3..1) for 40 column displays. 3086 3087- CONFIG_FLASH_VERIFY 3088 If defined, the content of the flash (destination) is compared 3089 against the source after the write operation. An error message 3090 will be printed when the contents are not identical. 3091 Please note that this option is useless in nearly all cases, 3092 since such flash programming errors usually are detected earlier 3093 while unprotecting/erasing/programming. Please only enable 3094 this option if you really know what you are doing. 3095 3096- CONFIG_SYS_RX_ETH_BUFFER: 3097 Defines the number of Ethernet receive buffers. On some 3098 Ethernet controllers it is recommended to set this value 3099 to 8 or even higher (EEPRO100 or 405 EMAC), since all 3100 buffers can be full shortly after enabling the interface 3101 on high Ethernet traffic. 3102 Defaults to 4 if not defined. 3103 3104- CONFIG_ENV_MAX_ENTRIES 3105 3106 Maximum number of entries in the hash table that is used 3107 internally to store the environment settings. The default 3108 setting is supposed to be generous and should work in most 3109 cases. This setting can be used to tune behaviour; see 3110 lib/hashtable.c for details. 3111 3112- CONFIG_ENV_FLAGS_LIST_DEFAULT 3113- CONFIG_ENV_FLAGS_LIST_STATIC 3114 Enable validation of the values given to environment variables when 3115 calling env set. Variables can be restricted to only decimal, 3116 hexadecimal, or boolean. If CONFIG_CMD_NET is also defined, 3117 the variables can also be restricted to IP address or MAC address. 3118 3119 The format of the list is: 3120 type_attribute = [s|d|x|b|i|m] 3121 access_attribute = [a|r|o|c] 3122 attributes = type_attribute[access_attribute] 3123 entry = variable_name[:attributes] 3124 list = entry[,list] 3125 3126 The type attributes are: 3127 s - String (default) 3128 d - Decimal 3129 x - Hexadecimal 3130 b - Boolean ([1yYtT|0nNfF]) 3131 i - IP address 3132 m - MAC address 3133 3134 The access attributes are: 3135 a - Any (default) 3136 r - Read-only 3137 o - Write-once 3138 c - Change-default 3139 3140 - CONFIG_ENV_FLAGS_LIST_DEFAULT 3141 Define this to a list (string) to define the ".flags" 3142 environment variable in the default or embedded environment. 3143 3144 - CONFIG_ENV_FLAGS_LIST_STATIC 3145 Define this to a list (string) to define validation that 3146 should be done if an entry is not found in the ".flags" 3147 environment variable. To override a setting in the static 3148 list, simply add an entry for the same variable name to the 3149 ".flags" variable. 3150 3151 If CONFIG_REGEX is defined, the variable_name above is evaluated as a 3152 regular expression. This allows multiple variables to define the same 3153 flags without explicitly listing them for each variable. 3154 3155- CONFIG_ENV_ACCESS_IGNORE_FORCE 3156 If defined, don't allow the -f switch to env set override variable 3157 access flags. 3158 3159- CONFIG_USE_STDINT 3160 If stdint.h is available with your toolchain you can define this 3161 option to enable it. You can provide option 'USE_STDINT=1' when 3162 building U-Boot to enable this. 3163 3164The following definitions that deal with the placement and management 3165of environment data (variable area); in general, we support the 3166following configurations: 3167 3168- CONFIG_BUILD_ENVCRC: 3169 3170 Builds up envcrc with the target environment so that external utils 3171 may easily extract it and embed it in final U-Boot images. 3172 3173BE CAREFUL! The first access to the environment happens quite early 3174in U-Boot initialization (when we try to get the setting of for the 3175console baudrate). You *MUST* have mapped your NVRAM area then, or 3176U-Boot will hang. 3177 3178Please note that even with NVRAM we still use a copy of the 3179environment in RAM: we could work on NVRAM directly, but we want to 3180keep settings there always unmodified except somebody uses "saveenv" 3181to save the current settings. 3182 3183BE CAREFUL! For some special cases, the local device can not use 3184"saveenv" command. For example, the local device will get the 3185environment stored in a remote NOR flash by SRIO or PCIE link, 3186but it can not erase, write this NOR flash by SRIO or PCIE interface. 3187 3188- CONFIG_NAND_ENV_DST 3189 3190 Defines address in RAM to which the nand_spl code should copy the 3191 environment. If redundant environment is used, it will be copied to 3192 CONFIG_NAND_ENV_DST + CONFIG_ENV_SIZE. 3193 3194Please note that the environment is read-only until the monitor 3195has been relocated to RAM and a RAM copy of the environment has been 3196created; also, when using EEPROM you will have to use env_get_f() 3197until then to read environment variables. 3198 3199The environment is protected by a CRC32 checksum. Before the monitor 3200is relocated into RAM, as a result of a bad CRC you will be working 3201with the compiled-in default environment - *silently*!!! [This is 3202necessary, because the first environment variable we need is the 3203"baudrate" setting for the console - if we have a bad CRC, we don't 3204have any device yet where we could complain.] 3205 3206Note: once the monitor has been relocated, then it will complain if 3207the default environment is used; a new CRC is computed as soon as you 3208use the "saveenv" command to store a valid environment. 3209 3210- CONFIG_SYS_FAULT_ECHO_LINK_DOWN: 3211 Echo the inverted Ethernet link state to the fault LED. 3212 3213 Note: If this option is active, then CONFIG_SYS_FAULT_MII_ADDR 3214 also needs to be defined. 3215 3216- CONFIG_SYS_FAULT_MII_ADDR: 3217 MII address of the PHY to check for the Ethernet link state. 3218 3219- CONFIG_NS16550_MIN_FUNCTIONS: 3220 Define this if you desire to only have use of the NS16550_init 3221 and NS16550_putc functions for the serial driver located at 3222 drivers/serial/ns16550.c. This option is useful for saving 3223 space for already greatly restricted images, including but not 3224 limited to NAND_SPL configurations. 3225 3226- CONFIG_DISPLAY_BOARDINFO 3227 Display information about the board that U-Boot is running on 3228 when U-Boot starts up. The board function checkboard() is called 3229 to do this. 3230 3231- CONFIG_DISPLAY_BOARDINFO_LATE 3232 Similar to the previous option, but display this information 3233 later, once stdio is running and output goes to the LCD, if 3234 present. 3235 3236- CONFIG_BOARD_SIZE_LIMIT: 3237 Maximum size of the U-Boot image. When defined, the 3238 build system checks that the actual size does not 3239 exceed it. 3240 3241Low Level (hardware related) configuration options: 3242--------------------------------------------------- 3243 3244- CONFIG_SYS_CACHELINE_SIZE: 3245 Cache Line Size of the CPU. 3246 3247- CONFIG_SYS_CCSRBAR_DEFAULT: 3248 Default (power-on reset) physical address of CCSR on Freescale 3249 PowerPC SOCs. 3250 3251- CONFIG_SYS_CCSRBAR: 3252 Virtual address of CCSR. On a 32-bit build, this is typically 3253 the same value as CONFIG_SYS_CCSRBAR_DEFAULT. 3254 3255- CONFIG_SYS_CCSRBAR_PHYS: 3256 Physical address of CCSR. CCSR can be relocated to a new 3257 physical address, if desired. In this case, this macro should 3258 be set to that address. Otherwise, it should be set to the 3259 same value as CONFIG_SYS_CCSRBAR_DEFAULT. For example, CCSR 3260 is typically relocated on 36-bit builds. It is recommended 3261 that this macro be defined via the _HIGH and _LOW macros: 3262 3263 #define CONFIG_SYS_CCSRBAR_PHYS ((CONFIG_SYS_CCSRBAR_PHYS_HIGH 3264 * 1ull) << 32 | CONFIG_SYS_CCSRBAR_PHYS_LOW) 3265 3266- CONFIG_SYS_CCSRBAR_PHYS_HIGH: 3267 Bits 33-36 of CONFIG_SYS_CCSRBAR_PHYS. This value is typically 3268 either 0 (32-bit build) or 0xF (36-bit build). This macro is 3269 used in assembly code, so it must not contain typecasts or 3270 integer size suffixes (e.g. "ULL"). 3271 3272- CONFIG_SYS_CCSRBAR_PHYS_LOW: 3273 Lower 32-bits of CONFIG_SYS_CCSRBAR_PHYS. This macro is 3274 used in assembly code, so it must not contain typecasts or 3275 integer size suffixes (e.g. "ULL"). 3276 3277- CONFIG_SYS_CCSR_DO_NOT_RELOCATE: 3278 If this macro is defined, then CONFIG_SYS_CCSRBAR_PHYS will be 3279 forced to a value that ensures that CCSR is not relocated. 3280 3281- Floppy Disk Support: 3282 CONFIG_SYS_FDC_DRIVE_NUMBER 3283 3284 the default drive number (default value 0) 3285 3286 CONFIG_SYS_ISA_IO_STRIDE 3287 3288 defines the spacing between FDC chipset registers 3289 (default value 1) 3290 3291 CONFIG_SYS_ISA_IO_OFFSET 3292 3293 defines the offset of register from address. It 3294 depends on which part of the data bus is connected to 3295 the FDC chipset. (default value 0) 3296 3297 If CONFIG_SYS_ISA_IO_STRIDE CONFIG_SYS_ISA_IO_OFFSET and 3298 CONFIG_SYS_FDC_DRIVE_NUMBER are undefined, they take their 3299 default value. 3300 3301 if CONFIG_SYS_FDC_HW_INIT is defined, then the function 3302 fdc_hw_init() is called at the beginning of the FDC 3303 setup. fdc_hw_init() must be provided by the board 3304 source code. It is used to make hardware-dependent 3305 initializations. 3306 3307- CONFIG_IDE_AHB: 3308 Most IDE controllers were designed to be connected with PCI 3309 interface. Only few of them were designed for AHB interface. 3310 When software is doing ATA command and data transfer to 3311 IDE devices through IDE-AHB controller, some additional 3312 registers accessing to these kind of IDE-AHB controller 3313 is required. 3314 3315- CONFIG_SYS_IMMR: Physical address of the Internal Memory. 3316 DO NOT CHANGE unless you know exactly what you're 3317 doing! (11-4) [MPC8xx systems only] 3318 3319- CONFIG_SYS_INIT_RAM_ADDR: 3320 3321 Start address of memory area that can be used for 3322 initial data and stack; please note that this must be 3323 writable memory that is working WITHOUT special 3324 initialization, i. e. you CANNOT use normal RAM which 3325 will become available only after programming the 3326 memory controller and running certain initialization 3327 sequences. 3328 3329 U-Boot uses the following memory types: 3330 - MPC8xx: IMMR (internal memory of the CPU) 3331 3332- CONFIG_SYS_GBL_DATA_OFFSET: 3333 3334 Offset of the initial data structure in the memory 3335 area defined by CONFIG_SYS_INIT_RAM_ADDR. Usually 3336 CONFIG_SYS_GBL_DATA_OFFSET is chosen such that the initial 3337 data is located at the end of the available space 3338 (sometimes written as (CONFIG_SYS_INIT_RAM_SIZE - 3339 GENERATED_GBL_DATA_SIZE), and the initial stack is just 3340 below that area (growing from (CONFIG_SYS_INIT_RAM_ADDR + 3341 CONFIG_SYS_GBL_DATA_OFFSET) downward. 3342 3343 Note: 3344 On the MPC824X (or other systems that use the data 3345 cache for initial memory) the address chosen for 3346 CONFIG_SYS_INIT_RAM_ADDR is basically arbitrary - it must 3347 point to an otherwise UNUSED address space between 3348 the top of RAM and the start of the PCI space. 3349 3350- CONFIG_SYS_SCCR: System Clock and reset Control Register (15-27) 3351 3352- CONFIG_SYS_OR_TIMING_SDRAM: 3353 SDRAM timing 3354 3355- CONFIG_SYS_MAMR_PTA: 3356 periodic timer for refresh 3357 3358- FLASH_BASE0_PRELIM, FLASH_BASE1_PRELIM, CONFIG_SYS_REMAP_OR_AM, 3359 CONFIG_SYS_PRELIM_OR_AM, CONFIG_SYS_OR_TIMING_FLASH, CONFIG_SYS_OR0_REMAP, 3360 CONFIG_SYS_OR0_PRELIM, CONFIG_SYS_BR0_PRELIM, CONFIG_SYS_OR1_REMAP, CONFIG_SYS_OR1_PRELIM, 3361 CONFIG_SYS_BR1_PRELIM: 3362 Memory Controller Definitions: BR0/1 and OR0/1 (FLASH) 3363 3364- SDRAM_BASE2_PRELIM, SDRAM_BASE3_PRELIM, SDRAM_MAX_SIZE, 3365 CONFIG_SYS_OR_TIMING_SDRAM, CONFIG_SYS_OR2_PRELIM, CONFIG_SYS_BR2_PRELIM, 3366 CONFIG_SYS_OR3_PRELIM, CONFIG_SYS_BR3_PRELIM: 3367 Memory Controller Definitions: BR2/3 and OR2/3 (SDRAM) 3368 3369- CONFIG_PCI_ENUM_ONLY 3370 Only scan through and get the devices on the buses. 3371 Don't do any setup work, presumably because someone or 3372 something has already done it, and we don't need to do it 3373 a second time. Useful for platforms that are pre-booted 3374 by coreboot or similar. 3375 3376- CONFIG_PCI_INDIRECT_BRIDGE: 3377 Enable support for indirect PCI bridges. 3378 3379- CONFIG_SYS_SRIO: 3380 Chip has SRIO or not 3381 3382- CONFIG_SRIO1: 3383 Board has SRIO 1 port available 3384 3385- CONFIG_SRIO2: 3386 Board has SRIO 2 port available 3387 3388- CONFIG_SRIO_PCIE_BOOT_MASTER 3389 Board can support master function for Boot from SRIO and PCIE 3390 3391- CONFIG_SYS_SRIOn_MEM_VIRT: 3392 Virtual Address of SRIO port 'n' memory region 3393 3394- CONFIG_SYS_SRIOn_MEM_PHYS: 3395 Physical Address of SRIO port 'n' memory region 3396 3397- CONFIG_SYS_SRIOn_MEM_SIZE: 3398 Size of SRIO port 'n' memory region 3399 3400- CONFIG_SYS_NAND_BUSWIDTH_16BIT 3401 Defined to tell the NAND controller that the NAND chip is using 3402 a 16 bit bus. 3403 Not all NAND drivers use this symbol. 3404 Example of drivers that use it: 3405 - drivers/mtd/nand/ndfc.c 3406 - drivers/mtd/nand/mxc_nand.c 3407 3408- CONFIG_SYS_NDFC_EBC0_CFG 3409 Sets the EBC0_CFG register for the NDFC. If not defined 3410 a default value will be used. 3411 3412- CONFIG_SPD_EEPROM 3413 Get DDR timing information from an I2C EEPROM. Common 3414 with pluggable memory modules such as SODIMMs 3415 3416 SPD_EEPROM_ADDRESS 3417 I2C address of the SPD EEPROM 3418 3419- CONFIG_SYS_SPD_BUS_NUM 3420 If SPD EEPROM is on an I2C bus other than the first 3421 one, specify here. Note that the value must resolve 3422 to something your driver can deal with. 3423 3424- CONFIG_SYS_DDR_RAW_TIMING 3425 Get DDR timing information from other than SPD. Common with 3426 soldered DDR chips onboard without SPD. DDR raw timing 3427 parameters are extracted from datasheet and hard-coded into 3428 header files or board specific files. 3429 3430- CONFIG_FSL_DDR_INTERACTIVE 3431 Enable interactive DDR debugging. See doc/README.fsl-ddr. 3432 3433- CONFIG_FSL_DDR_SYNC_REFRESH 3434 Enable sync of refresh for multiple controllers. 3435 3436- CONFIG_FSL_DDR_BIST 3437 Enable built-in memory test for Freescale DDR controllers. 3438 3439- CONFIG_SYS_83XX_DDR_USES_CS0 3440 Only for 83xx systems. If specified, then DDR should 3441 be configured using CS0 and CS1 instead of CS2 and CS3. 3442 3443- CONFIG_RMII 3444 Enable RMII mode for all FECs. 3445 Note that this is a global option, we can't 3446 have one FEC in standard MII mode and another in RMII mode. 3447 3448- CONFIG_CRC32_VERIFY 3449 Add a verify option to the crc32 command. 3450 The syntax is: 3451 3452 => crc32 -v <address> <count> <crc32> 3453 3454 Where address/count indicate a memory area 3455 and crc32 is the correct crc32 which the 3456 area should have. 3457 3458- CONFIG_LOOPW 3459 Add the "loopw" memory command. This only takes effect if 3460 the memory commands are activated globally (CONFIG_CMD_MEMORY). 3461 3462- CONFIG_MX_CYCLIC 3463 Add the "mdc" and "mwc" memory commands. These are cyclic 3464 "md/mw" commands. 3465 Examples: 3466 3467 => mdc.b 10 4 500 3468 This command will print 4 bytes (10,11,12,13) each 500 ms. 3469 3470 => mwc.l 100 12345678 10 3471 This command will write 12345678 to address 100 all 10 ms. 3472 3473 This only takes effect if the memory commands are activated 3474 globally (CONFIG_CMD_MEMORY). 3475 3476- CONFIG_SKIP_LOWLEVEL_INIT 3477 [ARM, NDS32, MIPS, RISC-V only] If this variable is defined, then certain 3478 low level initializations (like setting up the memory 3479 controller) are omitted and/or U-Boot does not 3480 relocate itself into RAM. 3481 3482 Normally this variable MUST NOT be defined. The only 3483 exception is when U-Boot is loaded (to RAM) by some 3484 other boot loader or by a debugger which performs 3485 these initializations itself. 3486 3487- CONFIG_SKIP_LOWLEVEL_INIT_ONLY 3488 [ARM926EJ-S only] This allows just the call to lowlevel_init() 3489 to be skipped. The normal CP15 init (such as enabling the 3490 instruction cache) is still performed. 3491 3492- CONFIG_SPL_BUILD 3493 Modifies the behaviour of start.S when compiling a loader 3494 that is executed before the actual U-Boot. E.g. when 3495 compiling a NAND SPL. 3496 3497- CONFIG_TPL_BUILD 3498 Modifies the behaviour of start.S when compiling a loader 3499 that is executed after the SPL and before the actual U-Boot. 3500 It is loaded by the SPL. 3501 3502- CONFIG_SYS_MPC85XX_NO_RESETVEC 3503 Only for 85xx systems. If this variable is specified, the section 3504 .resetvec is not kept and the section .bootpg is placed in the 3505 previous 4k of the .text section. 3506 3507- CONFIG_ARCH_MAP_SYSMEM 3508 Generally U-Boot (and in particular the md command) uses 3509 effective address. It is therefore not necessary to regard 3510 U-Boot address as virtual addresses that need to be translated 3511 to physical addresses. However, sandbox requires this, since 3512 it maintains its own little RAM buffer which contains all 3513 addressable memory. This option causes some memory accesses 3514 to be mapped through map_sysmem() / unmap_sysmem(). 3515 3516- CONFIG_X86_RESET_VECTOR 3517 If defined, the x86 reset vector code is included. This is not 3518 needed when U-Boot is running from Coreboot. 3519 3520- CONFIG_SPL_AM33XX_ENABLE_RTC32K_OSC: 3521 Enables the RTC32K OSC on AM33xx based plattforms 3522 3523- CONFIG_SYS_NAND_NO_SUBPAGE_WRITE 3524 Option to disable subpage write in NAND driver 3525 driver that uses this: 3526 drivers/mtd/nand/davinci_nand.c 3527 3528Freescale QE/FMAN Firmware Support: 3529----------------------------------- 3530 3531The Freescale QUICCEngine (QE) and Frame Manager (FMAN) both support the 3532loading of "firmware", which is encoded in the QE firmware binary format. 3533This firmware often needs to be loaded during U-Boot booting, so macros 3534are used to identify the storage device (NOR flash, SPI, etc) and the address 3535within that device. 3536 3537- CONFIG_SYS_FMAN_FW_ADDR 3538 The address in the storage device where the FMAN microcode is located. The 3539 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 3540 is also specified. 3541 3542- CONFIG_SYS_QE_FW_ADDR 3543 The address in the storage device where the QE microcode is located. The 3544 meaning of this address depends on which CONFIG_SYS_QE_FW_IN_xxx macro 3545 is also specified. 3546 3547- CONFIG_SYS_QE_FMAN_FW_LENGTH 3548 The maximum possible size of the firmware. The firmware binary format 3549 has a field that specifies the actual size of the firmware, but it 3550 might not be possible to read any part of the firmware unless some 3551 local storage is allocated to hold the entire firmware first. 3552 3553- CONFIG_SYS_QE_FMAN_FW_IN_NOR 3554 Specifies that QE/FMAN firmware is located in NOR flash, mapped as 3555 normal addressable memory via the LBC. CONFIG_SYS_FMAN_FW_ADDR is the 3556 virtual address in NOR flash. 3557 3558- CONFIG_SYS_QE_FMAN_FW_IN_NAND 3559 Specifies that QE/FMAN firmware is located in NAND flash. 3560 CONFIG_SYS_FMAN_FW_ADDR is the offset within NAND flash. 3561 3562- CONFIG_SYS_QE_FMAN_FW_IN_MMC 3563 Specifies that QE/FMAN firmware is located on the primary SD/MMC 3564 device. CONFIG_SYS_FMAN_FW_ADDR is the byte offset on that device. 3565 3566- CONFIG_SYS_QE_FMAN_FW_IN_REMOTE 3567 Specifies that QE/FMAN firmware is located in the remote (master) 3568 memory space. CONFIG_SYS_FMAN_FW_ADDR is a virtual address which 3569 can be mapped from slave TLB->slave LAW->slave SRIO or PCIE outbound 3570 window->master inbound window->master LAW->the ucode address in 3571 master's memory space. 3572 3573Freescale Layerscape Management Complex Firmware Support: 3574--------------------------------------------------------- 3575The Freescale Layerscape Management Complex (MC) supports the loading of 3576"firmware". 3577This firmware often needs to be loaded during U-Boot booting, so macros 3578are used to identify the storage device (NOR flash, SPI, etc) and the address 3579within that device. 3580 3581- CONFIG_FSL_MC_ENET 3582 Enable the MC driver for Layerscape SoCs. 3583 3584Freescale Layerscape Debug Server Support: 3585------------------------------------------- 3586The Freescale Layerscape Debug Server Support supports the loading of 3587"Debug Server firmware" and triggering SP boot-rom. 3588This firmware often needs to be loaded during U-Boot booting. 3589 3590- CONFIG_SYS_MC_RSV_MEM_ALIGN 3591 Define alignment of reserved memory MC requires 3592 3593Reproducible builds 3594------------------- 3595 3596In order to achieve reproducible builds, timestamps used in the U-Boot build 3597process have to be set to a fixed value. 3598 3599This is done using the SOURCE_DATE_EPOCH environment variable. 3600SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration 3601option for U-Boot or an environment variable in U-Boot. 3602 3603SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC. 3604 3605Building the Software: 3606====================== 3607 3608Building U-Boot has been tested in several native build environments 3609and in many different cross environments. Of course we cannot support 3610all possibly existing versions of cross development tools in all 3611(potentially obsolete) versions. In case of tool chain problems we 3612recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK) 3613which is extensively used to build and test U-Boot. 3614 3615If you are not using a native environment, it is assumed that you 3616have GNU cross compiling tools available in your path. In this case, 3617you must set the environment variable CROSS_COMPILE in your shell. 3618Note that no changes to the Makefile or any other source files are 3619necessary. For example using the ELDK on a 4xx CPU, please enter: 3620 3621 $ CROSS_COMPILE=ppc_4xx- 3622 $ export CROSS_COMPILE 3623 3624Note: If you wish to generate Windows versions of the utilities in 3625 the tools directory you can use the MinGW toolchain 3626 (http://www.mingw.org). Set your HOST tools to the MinGW 3627 toolchain and execute 'make tools'. For example: 3628 3629 $ make HOSTCC=i586-mingw32msvc-gcc HOSTSTRIP=i586-mingw32msvc-strip tools 3630 3631 Binaries such as tools/mkimage.exe will be created which can 3632 be executed on computers running Windows. 3633 3634U-Boot is intended to be simple to build. After installing the 3635sources you must configure U-Boot for one specific board type. This 3636is done by typing: 3637 3638 make NAME_defconfig 3639 3640where "NAME_defconfig" is the name of one of the existing configu- 3641rations; see boards.cfg for supported names. 3642 3643Note: for some board special configuration names may exist; check if 3644 additional information is available from the board vendor; for 3645 instance, the TQM823L systems are available without (standard) 3646 or with LCD support. You can select such additional "features" 3647 when choosing the configuration, i. e. 3648 3649 make TQM823L_defconfig 3650 - will configure for a plain TQM823L, i. e. no LCD support 3651 3652 make TQM823L_LCD_defconfig 3653 - will configure for a TQM823L with U-Boot console on LCD 3654 3655 etc. 3656 3657 3658Finally, type "make all", and you should get some working U-Boot 3659images ready for download to / installation on your system: 3660 3661- "u-boot.bin" is a raw binary image 3662- "u-boot" is an image in ELF binary format 3663- "u-boot.srec" is in Motorola S-Record format 3664 3665By default the build is performed locally and the objects are saved 3666in the source directory. One of the two methods can be used to change 3667this behavior and build U-Boot to some external directory: 3668 36691. Add O= to the make command line invocations: 3670 3671 make O=/tmp/build distclean 3672 make O=/tmp/build NAME_defconfig 3673 make O=/tmp/build all 3674 36752. Set environment variable KBUILD_OUTPUT to point to the desired location: 3676 3677 export KBUILD_OUTPUT=/tmp/build 3678 make distclean 3679 make NAME_defconfig 3680 make all 3681 3682Note that the command line "O=" setting overrides the KBUILD_OUTPUT environment 3683variable. 3684 3685User specific CPPFLAGS, AFLAGS and CFLAGS can be passed to the compiler by 3686setting the according environment variables KCPPFLAGS, KAFLAGS and KCFLAGS. 3687For example to treat all compiler warnings as errors: 3688 3689 make KCFLAGS=-Werror 3690 3691Please be aware that the Makefiles assume you are using GNU make, so 3692for instance on NetBSD you might need to use "gmake" instead of 3693native "make". 3694 3695 3696If the system board that you have is not listed, then you will need 3697to port U-Boot to your hardware platform. To do this, follow these 3698steps: 3699 37001. Create a new directory to hold your board specific code. Add any 3701 files you need. In your board directory, you will need at least 3702 the "Makefile" and a "<board>.c". 37032. Create a new configuration file "include/configs/<board>.h" for 3704 your board. 37053. If you're porting U-Boot to a new CPU, then also create a new 3706 directory to hold your CPU specific code. Add any files you need. 37074. Run "make <board>_defconfig" with your new name. 37085. Type "make", and you should get a working "u-boot.srec" file 3709 to be installed on your target system. 37106. Debug and solve any problems that might arise. 3711 [Of course, this last step is much harder than it sounds.] 3712 3713 3714Testing of U-Boot Modifications, Ports to New Hardware, etc.: 3715============================================================== 3716 3717If you have modified U-Boot sources (for instance added a new board 3718or support for new devices, a new CPU, etc.) you are expected to 3719provide feedback to the other developers. The feedback normally takes 3720the form of a "patch", i. e. a context diff against a certain (latest 3721official or latest in the git repository) version of U-Boot sources. 3722 3723But before you submit such a patch, please verify that your modifi- 3724cation did not break existing code. At least make sure that *ALL* of 3725the supported boards compile WITHOUT ANY compiler warnings. To do so, 3726just run the buildman script (tools/buildman/buildman), which will 3727configure and build U-Boot for ALL supported system. Be warned, this 3728will take a while. Please see the buildman README, or run 'buildman -H' 3729for documentation. 3730 3731 3732See also "U-Boot Porting Guide" below. 3733 3734 3735Monitor Commands - Overview: 3736============================ 3737 3738go - start application at address 'addr' 3739run - run commands in an environment variable 3740bootm - boot application image from memory 3741bootp - boot image via network using BootP/TFTP protocol 3742bootz - boot zImage from memory 3743tftpboot- boot image via network using TFTP protocol 3744 and env variables "ipaddr" and "serverip" 3745 (and eventually "gatewayip") 3746tftpput - upload a file via network using TFTP protocol 3747rarpboot- boot image via network using RARP/TFTP protocol 3748diskboot- boot from IDE devicebootd - boot default, i.e., run 'bootcmd' 3749loads - load S-Record file over serial line 3750loadb - load binary file over serial line (kermit mode) 3751md - memory display 3752mm - memory modify (auto-incrementing) 3753nm - memory modify (constant address) 3754mw - memory write (fill) 3755cp - memory copy 3756cmp - memory compare 3757crc32 - checksum calculation 3758i2c - I2C sub-system 3759sspi - SPI utility commands 3760base - print or set address offset 3761printenv- print environment variables 3762setenv - set environment variables 3763saveenv - save environment variables to persistent storage 3764protect - enable or disable FLASH write protection 3765erase - erase FLASH memory 3766flinfo - print FLASH memory information 3767nand - NAND memory operations (see doc/README.nand) 3768bdinfo - print Board Info structure 3769iminfo - print header information for application image 3770coninfo - print console devices and informations 3771ide - IDE sub-system 3772loop - infinite loop on address range 3773loopw - infinite write loop on address range 3774mtest - simple RAM test 3775icache - enable or disable instruction cache 3776dcache - enable or disable data cache 3777reset - Perform RESET of the CPU 3778echo - echo args to console 3779version - print monitor version 3780help - print online help 3781? - alias for 'help' 3782 3783 3784Monitor Commands - Detailed Description: 3785======================================== 3786 3787TODO. 3788 3789For now: just type "help <command>". 3790 3791 3792Environment Variables: 3793====================== 3794 3795U-Boot supports user configuration using Environment Variables which 3796can be made persistent by saving to Flash memory. 3797 3798Environment Variables are set using "setenv", printed using 3799"printenv", and saved to Flash using "saveenv". Using "setenv" 3800without a value can be used to delete a variable from the 3801environment. As long as you don't save the environment you are 3802working with an in-memory copy. In case the Flash area containing the 3803environment is erased by accident, a default environment is provided. 3804 3805Some configuration options can be set using Environment Variables. 3806 3807List of environment variables (most likely not complete): 3808 3809 baudrate - see CONFIG_BAUDRATE 3810 3811 bootdelay - see CONFIG_BOOTDELAY 3812 3813 bootcmd - see CONFIG_BOOTCOMMAND 3814 3815 bootargs - Boot arguments when booting an RTOS image 3816 3817 bootfile - Name of the image to load with TFTP 3818 3819 bootm_low - Memory range available for image processing in the bootm 3820 command can be restricted. This variable is given as 3821 a hexadecimal number and defines lowest address allowed 3822 for use by the bootm command. See also "bootm_size" 3823 environment variable. Address defined by "bootm_low" is 3824 also the base of the initial memory mapping for the Linux 3825 kernel -- see the description of CONFIG_SYS_BOOTMAPSZ and 3826 bootm_mapsize. 3827 3828 bootm_mapsize - Size of the initial memory mapping for the Linux kernel. 3829 This variable is given as a hexadecimal number and it 3830 defines the size of the memory region starting at base 3831 address bootm_low that is accessible by the Linux kernel 3832 during early boot. If unset, CONFIG_SYS_BOOTMAPSZ is used 3833 as the default value if it is defined, and bootm_size is 3834 used otherwise. 3835 3836 bootm_size - Memory range available for image processing in the bootm 3837 command can be restricted. This variable is given as 3838 a hexadecimal number and defines the size of the region 3839 allowed for use by the bootm command. See also "bootm_low" 3840 environment variable. 3841 3842 updatefile - Location of the software update file on a TFTP server, used 3843 by the automatic software update feature. Please refer to 3844 documentation in doc/README.update for more details. 3845 3846 autoload - if set to "no" (any string beginning with 'n'), 3847 "bootp" will just load perform a lookup of the 3848 configuration from the BOOTP server, but not try to 3849 load any image using TFTP 3850 3851 autostart - if set to "yes", an image loaded using the "bootp", 3852 "rarpboot", "tftpboot" or "diskboot" commands will 3853 be automatically started (by internally calling 3854 "bootm") 3855 3856 If set to "no", a standalone image passed to the 3857 "bootm" command will be copied to the load address 3858 (and eventually uncompressed), but NOT be started. 3859 This can be used to load and uncompress arbitrary 3860 data. 3861 3862 fdt_high - if set this restricts the maximum address that the 3863 flattened device tree will be copied into upon boot. 3864 For example, if you have a system with 1 GB memory 3865 at physical address 0x10000000, while Linux kernel 3866 only recognizes the first 704 MB as low memory, you 3867 may need to set fdt_high as 0x3C000000 to have the 3868 device tree blob be copied to the maximum address 3869 of the 704 MB low memory, so that Linux kernel can 3870 access it during the boot procedure. 3871 3872 If this is set to the special value 0xFFFFFFFF then 3873 the fdt will not be copied at all on boot. For this 3874 to work it must reside in writable memory, have 3875 sufficient padding on the end of it for u-boot to 3876 add the information it needs into it, and the memory 3877 must be accessible by the kernel. 3878 3879 fdtcontroladdr- if set this is the address of the control flattened 3880 device tree used by U-Boot when CONFIG_OF_CONTROL is 3881 defined. 3882 3883 i2cfast - (PPC405GP|PPC405EP only) 3884 if set to 'y' configures Linux I2C driver for fast 3885 mode (400kHZ). This environment variable is used in 3886 initialization code. So, for changes to be effective 3887 it must be saved and board must be reset. 3888 3889 initrd_high - restrict positioning of initrd images: 3890 If this variable is not set, initrd images will be 3891 copied to the highest possible address in RAM; this 3892 is usually what you want since it allows for 3893 maximum initrd size. If for some reason you want to 3894 make sure that the initrd image is loaded below the 3895 CONFIG_SYS_BOOTMAPSZ limit, you can set this environment 3896 variable to a value of "no" or "off" or "0". 3897 Alternatively, you can set it to a maximum upper 3898 address to use (U-Boot will still check that it 3899 does not overwrite the U-Boot stack and data). 3900 3901 For instance, when you have a system with 16 MB 3902 RAM, and want to reserve 4 MB from use by Linux, 3903 you can do this by adding "mem=12M" to the value of 3904 the "bootargs" variable. However, now you must make 3905 sure that the initrd image is placed in the first 3906 12 MB as well - this can be done with 3907 3908 setenv initrd_high 00c00000 3909 3910 If you set initrd_high to 0xFFFFFFFF, this is an 3911 indication to U-Boot that all addresses are legal 3912 for the Linux kernel, including addresses in flash 3913 memory. In this case U-Boot will NOT COPY the 3914 ramdisk at all. This may be useful to reduce the 3915 boot time on your system, but requires that this 3916 feature is supported by your Linux kernel. 3917 3918 ipaddr - IP address; needed for tftpboot command 3919 3920 loadaddr - Default load address for commands like "bootp", 3921 "rarpboot", "tftpboot", "loadb" or "diskboot" 3922 3923 loads_echo - see CONFIG_LOADS_ECHO 3924 3925 serverip - TFTP server IP address; needed for tftpboot command 3926 3927 bootretry - see CONFIG_BOOT_RETRY_TIME 3928 3929 bootdelaykey - see CONFIG_AUTOBOOT_DELAY_STR 3930 3931 bootstopkey - see CONFIG_AUTOBOOT_STOP_STR 3932 3933 ethprime - controls which interface is used first. 3934 3935 ethact - controls which interface is currently active. 3936 For example you can do the following 3937 3938 => setenv ethact FEC 3939 => ping 192.168.0.1 # traffic sent on FEC 3940 => setenv ethact SCC 3941 => ping 10.0.0.1 # traffic sent on SCC 3942 3943 ethrotate - When set to "no" U-Boot does not go through all 3944 available network interfaces. 3945 It just stays at the currently selected interface. 3946 3947 netretry - When set to "no" each network operation will 3948 either succeed or fail without retrying. 3949 When set to "once" the network operation will 3950 fail when all the available network interfaces 3951 are tried once without success. 3952 Useful on scripts which control the retry operation 3953 themselves. 3954 3955 npe_ucode - set load address for the NPE microcode 3956 3957 silent_linux - If set then Linux will be told to boot silently, by 3958 changing the console to be empty. If "yes" it will be 3959 made silent. If "no" it will not be made silent. If 3960 unset, then it will be made silent if the U-Boot console 3961 is silent. 3962 3963 tftpsrcp - If this is set, the value is used for TFTP's 3964 UDP source port. 3965 3966 tftpdstp - If this is set, the value is used for TFTP's UDP 3967 destination port instead of the Well Know Port 69. 3968 3969 tftpblocksize - Block size to use for TFTP transfers; if not set, 3970 we use the TFTP server's default block size 3971 3972 tftptimeout - Retransmission timeout for TFTP packets (in milli- 3973 seconds, minimum value is 1000 = 1 second). Defines 3974 when a packet is considered to be lost so it has to 3975 be retransmitted. The default is 5000 = 5 seconds. 3976 Lowering this value may make downloads succeed 3977 faster in networks with high packet loss rates or 3978 with unreliable TFTP servers. 3979 3980 tftptimeoutcountmax - maximum count of TFTP timeouts (no 3981 unit, minimum value = 0). Defines how many timeouts 3982 can happen during a single file transfer before that 3983 transfer is aborted. The default is 10, and 0 means 3984 'no timeouts allowed'. Increasing this value may help 3985 downloads succeed with high packet loss rates, or with 3986 unreliable TFTP servers or client hardware. 3987 3988 vlan - When set to a value < 4095 the traffic over 3989 Ethernet is encapsulated/received over 802.1q 3990 VLAN tagged frames. 3991 3992 bootpretryperiod - Period during which BOOTP/DHCP sends retries. 3993 Unsigned value, in milliseconds. If not set, the period will 3994 be either the default (28000), or a value based on 3995 CONFIG_NET_RETRY_COUNT, if defined. This value has 3996 precedence over the valu based on CONFIG_NET_RETRY_COUNT. 3997 3998The following image location variables contain the location of images 3999used in booting. The "Image" column gives the role of the image and is 4000not an environment variable name. The other columns are environment 4001variable names. "File Name" gives the name of the file on a TFTP 4002server, "RAM Address" gives the location in RAM the image will be 4003loaded to, and "Flash Location" gives the image's address in NOR 4004flash or offset in NAND flash. 4005 4006*Note* - these variables don't have to be defined for all boards, some 4007boards currently use other variables for these purposes, and some 4008boards use these variables for other purposes. 4009 4010Image File Name RAM Address Flash Location 4011----- --------- ----------- -------------- 4012u-boot u-boot u-boot_addr_r u-boot_addr 4013Linux kernel bootfile kernel_addr_r kernel_addr 4014device tree blob fdtfile fdt_addr_r fdt_addr 4015ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr 4016 4017The following environment variables may be used and automatically 4018updated by the network boot commands ("bootp" and "rarpboot"), 4019depending the information provided by your boot server: 4020 4021 bootfile - see above 4022 dnsip - IP address of your Domain Name Server 4023 dnsip2 - IP address of your secondary Domain Name Server 4024 gatewayip - IP address of the Gateway (Router) to use 4025 hostname - Target hostname 4026 ipaddr - see above 4027 netmask - Subnet Mask 4028 rootpath - Pathname of the root filesystem on the NFS server 4029 serverip - see above 4030 4031 4032There are two special Environment Variables: 4033 4034 serial# - contains hardware identification information such 4035 as type string and/or serial number 4036 ethaddr - Ethernet address 4037 4038These variables can be set only once (usually during manufacturing of 4039the board). U-Boot refuses to delete or overwrite these variables 4040once they have been set once. 4041 4042 4043Further special Environment Variables: 4044 4045 ver - Contains the U-Boot version string as printed 4046 with the "version" command. This variable is 4047 readonly (see CONFIG_VERSION_VARIABLE). 4048 4049 4050Please note that changes to some configuration parameters may take 4051only effect after the next boot (yes, that's just like Windoze :-). 4052 4053 4054Callback functions for environment variables: 4055--------------------------------------------- 4056 4057For some environment variables, the behavior of u-boot needs to change 4058when their values are changed. This functionality allows functions to 4059be associated with arbitrary variables. On creation, overwrite, or 4060deletion, the callback will provide the opportunity for some side 4061effect to happen or for the change to be rejected. 4062 4063The callbacks are named and associated with a function using the 4064U_BOOT_ENV_CALLBACK macro in your board or driver code. 4065 4066These callbacks are associated with variables in one of two ways. The 4067static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC 4068in the board configuration to a string that defines a list of 4069associations. The list must be in the following format: 4070 4071 entry = variable_name[:callback_name] 4072 list = entry[,list] 4073 4074If the callback name is not specified, then the callback is deleted. 4075Spaces are also allowed anywhere in the list. 4076 4077Callbacks can also be associated by defining the ".callbacks" variable 4078with the same list format above. Any association in ".callbacks" will 4079override any association in the static list. You can define 4080CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the 4081".callbacks" environment variable in the default or embedded environment. 4082 4083If CONFIG_REGEX is defined, the variable_name above is evaluated as a 4084regular expression. This allows multiple variables to be connected to 4085the same callback without explicitly listing them all out. 4086 4087 4088Command Line Parsing: 4089===================== 4090 4091There are two different command line parsers available with U-Boot: 4092the old "simple" one, and the much more powerful "hush" shell: 4093 4094Old, simple command line parser: 4095-------------------------------- 4096 4097- supports environment variables (through setenv / saveenv commands) 4098- several commands on one line, separated by ';' 4099- variable substitution using "... ${name} ..." syntax 4100- special characters ('$', ';') can be escaped by prefixing with '\', 4101 for example: 4102 setenv bootcmd bootm \${address} 4103- You can also escape text by enclosing in single apostrophes, for example: 4104 setenv addip 'setenv bootargs $bootargs ip=$ipaddr:$serverip:$gatewayip:$netmask:$hostname::off' 4105 4106Hush shell: 4107----------- 4108 4109- similar to Bourne shell, with control structures like 4110 if...then...else...fi, for...do...done; while...do...done, 4111 until...do...done, ... 4112- supports environment ("global") variables (through setenv / saveenv 4113 commands) and local shell variables (through standard shell syntax 4114 "name=value"); only environment variables can be used with "run" 4115 command 4116 4117General rules: 4118-------------- 4119 4120(1) If a command line (or an environment variable executed by a "run" 4121 command) contains several commands separated by semicolon, and 4122 one of these commands fails, then the remaining commands will be 4123 executed anyway. 4124 4125(2) If you execute several variables with one call to run (i. e. 4126 calling run with a list of variables as arguments), any failing 4127 command will cause "run" to terminate, i. e. the remaining 4128 variables are not executed. 4129 4130Note for Redundant Ethernet Interfaces: 4131======================================= 4132 4133Some boards come with redundant Ethernet interfaces; U-Boot supports 4134such configurations and is capable of automatic selection of a 4135"working" interface when needed. MAC assignment works as follows: 4136 4137Network interfaces are numbered eth0, eth1, eth2, ... Corresponding 4138MAC addresses can be stored in the environment as "ethaddr" (=>eth0), 4139"eth1addr" (=>eth1), "eth2addr", ... 4140 4141If the network interface stores some valid MAC address (for instance 4142in SROM), this is used as default address if there is NO correspon- 4143ding setting in the environment; if the corresponding environment 4144variable is set, this overrides the settings in the card; that means: 4145 4146o If the SROM has a valid MAC address, and there is no address in the 4147 environment, the SROM's address is used. 4148 4149o If there is no valid address in the SROM, and a definition in the 4150 environment exists, then the value from the environment variable is 4151 used. 4152 4153o If both the SROM and the environment contain a MAC address, and 4154 both addresses are the same, this MAC address is used. 4155 4156o If both the SROM and the environment contain a MAC address, and the 4157 addresses differ, the value from the environment is used and a 4158 warning is printed. 4159 4160o If neither SROM nor the environment contain a MAC address, an error 4161 is raised. If CONFIG_NET_RANDOM_ETHADDR is defined, then in this case 4162 a random, locally-assigned MAC is used. 4163 4164If Ethernet drivers implement the 'write_hwaddr' function, valid MAC addresses 4165will be programmed into hardware as part of the initialization process. This 4166may be skipped by setting the appropriate 'ethmacskip' environment variable. 4167The naming convention is as follows: 4168"ethmacskip" (=>eth0), "eth1macskip" (=>eth1) etc. 4169 4170Image Formats: 4171============== 4172 4173U-Boot is capable of booting (and performing other auxiliary operations on) 4174images in two formats: 4175 4176New uImage format (FIT) 4177----------------------- 4178 4179Flexible and powerful format based on Flattened Image Tree -- FIT (similar 4180to Flattened Device Tree). It allows the use of images with multiple 4181components (several kernels, ramdisks, etc.), with contents protected by 4182SHA1, MD5 or CRC32. More details are found in the doc/uImage.FIT directory. 4183 4184 4185Old uImage format 4186----------------- 4187 4188Old image format is based on binary files which can be basically anything, 4189preceded by a special header; see the definitions in include/image.h for 4190details; basically, the header defines the following image properties: 4191 4192* Target Operating System (Provisions for OpenBSD, NetBSD, FreeBSD, 4193 4.4BSD, Linux, SVR4, Esix, Solaris, Irix, SCO, Dell, NCR, VxWorks, 4194 LynxOS, pSOS, QNX, RTEMS, INTEGRITY; 4195 Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS, 4196 INTEGRITY). 4197* Target CPU Architecture (Provisions for Alpha, ARM, Intel x86, 4198 IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit; 4199 Currently supported: ARM, Intel x86, MIPS, NDS32, Nios II, PowerPC). 4200* Compression Type (uncompressed, gzip, bzip2) 4201* Load Address 4202* Entry Point 4203* Image Name 4204* Image Timestamp 4205 4206The header is marked by a special Magic Number, and both the header 4207and the data portions of the image are secured against corruption by 4208CRC32 checksums. 4209 4210 4211Linux Support: 4212============== 4213 4214Although U-Boot should support any OS or standalone application 4215easily, the main focus has always been on Linux during the design of 4216U-Boot. 4217 4218U-Boot includes many features that so far have been part of some 4219special "boot loader" code within the Linux kernel. Also, any 4220"initrd" images to be used are no longer part of one big Linux image; 4221instead, kernel and "initrd" are separate images. This implementation 4222serves several purposes: 4223 4224- the same features can be used for other OS or standalone 4225 applications (for instance: using compressed images to reduce the 4226 Flash memory footprint) 4227 4228- it becomes much easier to port new Linux kernel versions because 4229 lots of low-level, hardware dependent stuff are done by U-Boot 4230 4231- the same Linux kernel image can now be used with different "initrd" 4232 images; of course this also means that different kernel images can 4233 be run with the same "initrd". This makes testing easier (you don't 4234 have to build a new "zImage.initrd" Linux image when you just 4235 change a file in your "initrd"). Also, a field-upgrade of the 4236 software is easier now. 4237 4238 4239Linux HOWTO: 4240============ 4241 4242Porting Linux to U-Boot based systems: 4243--------------------------------------- 4244 4245U-Boot cannot save you from doing all the necessary modifications to 4246configure the Linux device drivers for use with your target hardware 4247(no, we don't intend to provide a full virtual machine interface to 4248Linux :-). 4249 4250But now you can ignore ALL boot loader code (in arch/powerpc/mbxboot). 4251 4252Just make sure your machine specific header file (for instance 4253include/asm-ppc/tqm8xx.h) includes the same definition of the Board 4254Information structure as we define in include/asm-<arch>/u-boot.h, 4255and make sure that your definition of IMAP_ADDR uses the same value 4256as your U-Boot configuration in CONFIG_SYS_IMMR. 4257 4258Note that U-Boot now has a driver model, a unified model for drivers. 4259If you are adding a new driver, plumb it into driver model. If there 4260is no uclass available, you are encouraged to create one. See 4261doc/driver-model. 4262 4263 4264Configuring the Linux kernel: 4265----------------------------- 4266 4267No specific requirements for U-Boot. Make sure you have some root 4268device (initial ramdisk, NFS) for your target system. 4269 4270 4271Building a Linux Image: 4272----------------------- 4273 4274With U-Boot, "normal" build targets like "zImage" or "bzImage" are 4275not used. If you use recent kernel source, a new build target 4276"uImage" will exist which automatically builds an image usable by 4277U-Boot. Most older kernels also have support for a "pImage" target, 4278which was introduced for our predecessor project PPCBoot and uses a 4279100% compatible format. 4280 4281Example: 4282 4283 make TQM850L_defconfig 4284 make oldconfig 4285 make dep 4286 make uImage 4287 4288The "uImage" build target uses a special tool (in 'tools/mkimage') to 4289encapsulate a compressed Linux kernel image with header information, 4290CRC32 checksum etc. for use with U-Boot. This is what we are doing: 4291 4292* build a standard "vmlinux" kernel image (in ELF binary format): 4293 4294* convert the kernel into a raw binary image: 4295 4296 ${CROSS_COMPILE}-objcopy -O binary \ 4297 -R .note -R .comment \ 4298 -S vmlinux linux.bin 4299 4300* compress the binary image: 4301 4302 gzip -9 linux.bin 4303 4304* package compressed binary image for U-Boot: 4305 4306 mkimage -A ppc -O linux -T kernel -C gzip \ 4307 -a 0 -e 0 -n "Linux Kernel Image" \ 4308 -d linux.bin.gz uImage 4309 4310 4311The "mkimage" tool can also be used to create ramdisk images for use 4312with U-Boot, either separated from the Linux kernel image, or 4313combined into one file. "mkimage" encapsulates the images with a 64 4314byte header containing information about target architecture, 4315operating system, image type, compression method, entry points, time 4316stamp, CRC32 checksums, etc. 4317 4318"mkimage" can be called in two ways: to verify existing images and 4319print the header information, or to build new images. 4320 4321In the first form (with "-l" option) mkimage lists the information 4322contained in the header of an existing U-Boot image; this includes 4323checksum verification: 4324 4325 tools/mkimage -l image 4326 -l ==> list image header information 4327 4328The second form (with "-d" option) is used to build a U-Boot image 4329from a "data file" which is used as image payload: 4330 4331 tools/mkimage -A arch -O os -T type -C comp -a addr -e ep \ 4332 -n name -d data_file image 4333 -A ==> set architecture to 'arch' 4334 -O ==> set operating system to 'os' 4335 -T ==> set image type to 'type' 4336 -C ==> set compression type 'comp' 4337 -a ==> set load address to 'addr' (hex) 4338 -e ==> set entry point to 'ep' (hex) 4339 -n ==> set image name to 'name' 4340 -d ==> use image data from 'datafile' 4341 4342Right now, all Linux kernels for PowerPC systems use the same load 4343address (0x00000000), but the entry point address depends on the 4344kernel version: 4345 4346- 2.2.x kernels have the entry point at 0x0000000C, 4347- 2.3.x and later kernels have the entry point at 0x00000000. 4348 4349So a typical call to build a U-Boot image would read: 4350 4351 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4352 > -A ppc -O linux -T kernel -C gzip -a 0 -e 0 \ 4353 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz \ 4354 > examples/uImage.TQM850L 4355 Image Name: 2.4.4 kernel for TQM850L 4356 Created: Wed Jul 19 02:34:59 2000 4357 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4358 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4359 Load Address: 0x00000000 4360 Entry Point: 0x00000000 4361 4362To verify the contents of the image (or check for corruption): 4363 4364 -> tools/mkimage -l examples/uImage.TQM850L 4365 Image Name: 2.4.4 kernel for TQM850L 4366 Created: Wed Jul 19 02:34:59 2000 4367 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4368 Data Size: 335725 Bytes = 327.86 kB = 0.32 MB 4369 Load Address: 0x00000000 4370 Entry Point: 0x00000000 4371 4372NOTE: for embedded systems where boot time is critical you can trade 4373speed for memory and install an UNCOMPRESSED image instead: this 4374needs more space in Flash, but boots much faster since it does not 4375need to be uncompressed: 4376 4377 -> gunzip /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux.gz 4378 -> tools/mkimage -n '2.4.4 kernel for TQM850L' \ 4379 > -A ppc -O linux -T kernel -C none -a 0 -e 0 \ 4380 > -d /opt/elsk/ppc_8xx/usr/src/linux-2.4.4/arch/powerpc/coffboot/vmlinux \ 4381 > examples/uImage.TQM850L-uncompressed 4382 Image Name: 2.4.4 kernel for TQM850L 4383 Created: Wed Jul 19 02:34:59 2000 4384 Image Type: PowerPC Linux Kernel Image (uncompressed) 4385 Data Size: 792160 Bytes = 773.59 kB = 0.76 MB 4386 Load Address: 0x00000000 4387 Entry Point: 0x00000000 4388 4389 4390Similar you can build U-Boot images from a 'ramdisk.image.gz' file 4391when your kernel is intended to use an initial ramdisk: 4392 4393 -> tools/mkimage -n 'Simple Ramdisk Image' \ 4394 > -A ppc -O linux -T ramdisk -C gzip \ 4395 > -d /LinuxPPC/images/SIMPLE-ramdisk.image.gz examples/simple-initrd 4396 Image Name: Simple Ramdisk Image 4397 Created: Wed Jan 12 14:01:50 2000 4398 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4399 Data Size: 566530 Bytes = 553.25 kB = 0.54 MB 4400 Load Address: 0x00000000 4401 Entry Point: 0x00000000 4402 4403The "dumpimage" is a tool to disassemble images built by mkimage. Its "-i" 4404option performs the converse operation of the mkimage's second form (the "-d" 4405option). Given an image built by mkimage, the dumpimage extracts a "data file" 4406from the image: 4407 4408 tools/dumpimage -i image -T type -p position data_file 4409 -i ==> extract from the 'image' a specific 'data_file' 4410 -T ==> set image type to 'type' 4411 -p ==> 'position' (starting at 0) of the 'data_file' inside the 'image' 4412 4413 4414Installing a Linux Image: 4415------------------------- 4416 4417To downloading a U-Boot image over the serial (console) interface, 4418you must convert the image to S-Record format: 4419 4420 objcopy -I binary -O srec examples/image examples/image.srec 4421 4422The 'objcopy' does not understand the information in the U-Boot 4423image header, so the resulting S-Record file will be relative to 4424address 0x00000000. To load it to a given address, you need to 4425specify the target address as 'offset' parameter with the 'loads' 4426command. 4427 4428Example: install the image to address 0x40100000 (which on the 4429TQM8xxL is in the first Flash bank): 4430 4431 => erase 40100000 401FFFFF 4432 4433 .......... done 4434 Erased 8 sectors 4435 4436 => loads 40100000 4437 ## Ready for S-Record download ... 4438 ~>examples/image.srec 4439 1 2 3 4 5 6 7 8 9 10 11 12 13 ... 4440 ... 4441 15989 15990 15991 15992 4442 [file transfer complete] 4443 [connected] 4444 ## Start Addr = 0x00000000 4445 4446 4447You can check the success of the download using the 'iminfo' command; 4448this includes a checksum verification so you can be sure no data 4449corruption happened: 4450 4451 => imi 40100000 4452 4453 ## Checking Image at 40100000 ... 4454 Image Name: 2.2.13 for initrd on TQM850L 4455 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4456 Data Size: 335725 Bytes = 327 kB = 0 MB 4457 Load Address: 00000000 4458 Entry Point: 0000000c 4459 Verifying Checksum ... OK 4460 4461 4462Boot Linux: 4463----------- 4464 4465The "bootm" command is used to boot an application that is stored in 4466memory (RAM or Flash). In case of a Linux kernel image, the contents 4467of the "bootargs" environment variable is passed to the kernel as 4468parameters. You can check and modify this variable using the 4469"printenv" and "setenv" commands: 4470 4471 4472 => printenv bootargs 4473 bootargs=root=/dev/ram 4474 4475 => setenv bootargs root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4476 4477 => printenv bootargs 4478 bootargs=root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4479 4480 => bootm 40020000 4481 ## Booting Linux kernel at 40020000 ... 4482 Image Name: 2.2.13 for NFS on TQM850L 4483 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4484 Data Size: 381681 Bytes = 372 kB = 0 MB 4485 Load Address: 00000000 4486 Entry Point: 0000000c 4487 Verifying Checksum ... OK 4488 Uncompressing Kernel Image ... OK 4489 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 4490 Boot arguments: root=/dev/nfs rw nfsroot=10.0.0.2:/LinuxPPC nfsaddrs=10.0.0.99:10.0.0.2 4491 time_init: decrementer frequency = 187500000/60 4492 Calibrating delay loop... 49.77 BogoMIPS 4493 Memory: 15208k available (700k kernel code, 444k data, 32k init) [c0000000,c1000000] 4494 ... 4495 4496If you want to boot a Linux kernel with initial RAM disk, you pass 4497the memory addresses of both the kernel and the initrd image (PPBCOOT 4498format!) to the "bootm" command: 4499 4500 => imi 40100000 40200000 4501 4502 ## Checking Image at 40100000 ... 4503 Image Name: 2.2.13 for initrd on TQM850L 4504 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4505 Data Size: 335725 Bytes = 327 kB = 0 MB 4506 Load Address: 00000000 4507 Entry Point: 0000000c 4508 Verifying Checksum ... OK 4509 4510 ## Checking Image at 40200000 ... 4511 Image Name: Simple Ramdisk Image 4512 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4513 Data Size: 566530 Bytes = 553 kB = 0 MB 4514 Load Address: 00000000 4515 Entry Point: 00000000 4516 Verifying Checksum ... OK 4517 4518 => bootm 40100000 40200000 4519 ## Booting Linux kernel at 40100000 ... 4520 Image Name: 2.2.13 for initrd on TQM850L 4521 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4522 Data Size: 335725 Bytes = 327 kB = 0 MB 4523 Load Address: 00000000 4524 Entry Point: 0000000c 4525 Verifying Checksum ... OK 4526 Uncompressing Kernel Image ... OK 4527 ## Loading RAMDisk Image at 40200000 ... 4528 Image Name: Simple Ramdisk Image 4529 Image Type: PowerPC Linux RAMDisk Image (gzip compressed) 4530 Data Size: 566530 Bytes = 553 kB = 0 MB 4531 Load Address: 00000000 4532 Entry Point: 00000000 4533 Verifying Checksum ... OK 4534 Loading Ramdisk ... OK 4535 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 4536 Boot arguments: root=/dev/ram 4537 time_init: decrementer frequency = 187500000/60 4538 Calibrating delay loop... 49.77 BogoMIPS 4539 ... 4540 RAMDISK: Compressed image found at block 0 4541 VFS: Mounted root (ext2 filesystem). 4542 4543 bash# 4544 4545Boot Linux and pass a flat device tree: 4546----------- 4547 4548First, U-Boot must be compiled with the appropriate defines. See the section 4549titled "Linux Kernel Interface" above for a more in depth explanation. The 4550following is an example of how to start a kernel and pass an updated 4551flat device tree: 4552 4553=> print oftaddr 4554oftaddr=0x300000 4555=> print oft 4556oft=oftrees/mpc8540ads.dtb 4557=> tftp $oftaddr $oft 4558Speed: 1000, full duplex 4559Using TSEC0 device 4560TFTP from server 192.168.1.1; our IP address is 192.168.1.101 4561Filename 'oftrees/mpc8540ads.dtb'. 4562Load address: 0x300000 4563Loading: # 4564done 4565Bytes transferred = 4106 (100a hex) 4566=> tftp $loadaddr $bootfile 4567Speed: 1000, full duplex 4568Using TSEC0 device 4569TFTP from server 192.168.1.1; our IP address is 192.168.1.2 4570Filename 'uImage'. 4571Load address: 0x200000 4572Loading:############ 4573done 4574Bytes transferred = 1029407 (fb51f hex) 4575=> print loadaddr 4576loadaddr=200000 4577=> print oftaddr 4578oftaddr=0x300000 4579=> bootm $loadaddr - $oftaddr 4580## Booting image at 00200000 ... 4581 Image Name: Linux-2.6.17-dirty 4582 Image Type: PowerPC Linux Kernel Image (gzip compressed) 4583 Data Size: 1029343 Bytes = 1005.2 kB 4584 Load Address: 00000000 4585 Entry Point: 00000000 4586 Verifying Checksum ... OK 4587 Uncompressing Kernel Image ... OK 4588Booting using flat device tree at 0x300000 4589Using MPC85xx ADS machine description 4590Memory CAM mapping: CAM0=256Mb, CAM1=256Mb, CAM2=0Mb residual: 0Mb 4591[snip] 4592 4593 4594More About U-Boot Image Types: 4595------------------------------ 4596 4597U-Boot supports the following image types: 4598 4599 "Standalone Programs" are directly runnable in the environment 4600 provided by U-Boot; it is expected that (if they behave 4601 well) you can continue to work in U-Boot after return from 4602 the Standalone Program. 4603 "OS Kernel Images" are usually images of some Embedded OS which 4604 will take over control completely. Usually these programs 4605 will install their own set of exception handlers, device 4606 drivers, set up the MMU, etc. - this means, that you cannot 4607 expect to re-enter U-Boot except by resetting the CPU. 4608 "RAMDisk Images" are more or less just data blocks, and their 4609 parameters (address, size) are passed to an OS kernel that is 4610 being started. 4611 "Multi-File Images" contain several images, typically an OS 4612 (Linux) kernel image and one or more data images like 4613 RAMDisks. This construct is useful for instance when you want 4614 to boot over the network using BOOTP etc., where the boot 4615 server provides just a single image file, but you want to get 4616 for instance an OS kernel and a RAMDisk image. 4617 4618 "Multi-File Images" start with a list of image sizes, each 4619 image size (in bytes) specified by an "uint32_t" in network 4620 byte order. This list is terminated by an "(uint32_t)0". 4621 Immediately after the terminating 0 follow the images, one by 4622 one, all aligned on "uint32_t" boundaries (size rounded up to 4623 a multiple of 4 bytes). 4624 4625 "Firmware Images" are binary images containing firmware (like 4626 U-Boot or FPGA images) which usually will be programmed to 4627 flash memory. 4628 4629 "Script files" are command sequences that will be executed by 4630 U-Boot's command interpreter; this feature is especially 4631 useful when you configure U-Boot to use a real shell (hush) 4632 as command interpreter. 4633 4634Booting the Linux zImage: 4635------------------------- 4636 4637On some platforms, it's possible to boot Linux zImage. This is done 4638using the "bootz" command. The syntax of "bootz" command is the same 4639as the syntax of "bootm" command. 4640 4641Note, defining the CONFIG_SUPPORT_RAW_INITRD allows user to supply 4642kernel with raw initrd images. The syntax is slightly different, the 4643address of the initrd must be augmented by it's size, in the following 4644format: "<initrd addres>:<initrd size>". 4645 4646 4647Standalone HOWTO: 4648================= 4649 4650One of the features of U-Boot is that you can dynamically load and 4651run "standalone" applications, which can use some resources of 4652U-Boot like console I/O functions or interrupt services. 4653 4654Two simple examples are included with the sources: 4655 4656"Hello World" Demo: 4657------------------- 4658 4659'examples/hello_world.c' contains a small "Hello World" Demo 4660application; it is automatically compiled when you build U-Boot. 4661It's configured to run at address 0x00040004, so you can play with it 4662like that: 4663 4664 => loads 4665 ## Ready for S-Record download ... 4666 ~>examples/hello_world.srec 4667 1 2 3 4 5 6 7 8 9 10 11 ... 4668 [file transfer complete] 4669 [connected] 4670 ## Start Addr = 0x00040004 4671 4672 => go 40004 Hello World! This is a test. 4673 ## Starting application at 0x00040004 ... 4674 Hello World 4675 argc = 7 4676 argv[0] = "40004" 4677 argv[1] = "Hello" 4678 argv[2] = "World!" 4679 argv[3] = "This" 4680 argv[4] = "is" 4681 argv[5] = "a" 4682 argv[6] = "test." 4683 argv[7] = "<NULL>" 4684 Hit any key to exit ... 4685 4686 ## Application terminated, rc = 0x0 4687 4688Another example, which demonstrates how to register a CPM interrupt 4689handler with the U-Boot code, can be found in 'examples/timer.c'. 4690Here, a CPM timer is set up to generate an interrupt every second. 4691The interrupt service routine is trivial, just printing a '.' 4692character, but this is just a demo program. The application can be 4693controlled by the following keys: 4694 4695 ? - print current values og the CPM Timer registers 4696 b - enable interrupts and start timer 4697 e - stop timer and disable interrupts 4698 q - quit application 4699 4700 => loads 4701 ## Ready for S-Record download ... 4702 ~>examples/timer.srec 4703 1 2 3 4 5 6 7 8 9 10 11 ... 4704 [file transfer complete] 4705 [connected] 4706 ## Start Addr = 0x00040004 4707 4708 => go 40004 4709 ## Starting application at 0x00040004 ... 4710 TIMERS=0xfff00980 4711 Using timer 1 4712 tgcr @ 0xfff00980, tmr @ 0xfff00990, trr @ 0xfff00994, tcr @ 0xfff00998, tcn @ 0xfff0099c, ter @ 0xfff009b0 4713 4714Hit 'b': 4715 [q, b, e, ?] Set interval 1000000 us 4716 Enabling timer 4717Hit '?': 4718 [q, b, e, ?] ........ 4719 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0xef6, ter=0x0 4720Hit '?': 4721 [q, b, e, ?] . 4722 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x2ad4, ter=0x0 4723Hit '?': 4724 [q, b, e, ?] . 4725 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x1efc, ter=0x0 4726Hit '?': 4727 [q, b, e, ?] . 4728 tgcr=0x1, tmr=0xff1c, trr=0x3d09, tcr=0x0, tcn=0x169d, ter=0x0 4729Hit 'e': 4730 [q, b, e, ?] ...Stopping timer 4731Hit 'q': 4732 [q, b, e, ?] ## Application terminated, rc = 0x0 4733 4734 4735Minicom warning: 4736================ 4737 4738Over time, many people have reported problems when trying to use the 4739"minicom" terminal emulation program for serial download. I (wd) 4740consider minicom to be broken, and recommend not to use it. Under 4741Unix, I recommend to use C-Kermit for general purpose use (and 4742especially for kermit binary protocol download ("loadb" command), and 4743use "cu" for S-Record download ("loads" command). See 4744http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3. 4745for help with kermit. 4746 4747 4748Nevertheless, if you absolutely want to use it try adding this 4749configuration to your "File transfer protocols" section: 4750 4751 Name Program Name U/D FullScr IO-Red. Multi 4752 X kermit /usr/bin/kermit -i -l %l -s Y U Y N N 4753 Y kermit /usr/bin/kermit -i -l %l -r N D Y N N 4754 4755 4756NetBSD Notes: 4757============= 4758 4759Starting at version 0.9.2, U-Boot supports NetBSD both as host 4760(build U-Boot) and target system (boots NetBSD/mpc8xx). 4761 4762Building requires a cross environment; it is known to work on 4763NetBSD/i386 with the cross-powerpc-netbsd-1.3 package (you will also 4764need gmake since the Makefiles are not compatible with BSD make). 4765Note that the cross-powerpc package does not install include files; 4766attempting to build U-Boot will fail because <machine/ansi.h> is 4767missing. This file has to be installed and patched manually: 4768 4769 # cd /usr/pkg/cross/powerpc-netbsd/include 4770 # mkdir powerpc 4771 # ln -s powerpc machine 4772 # cp /usr/src/sys/arch/powerpc/include/ansi.h powerpc/ansi.h 4773 # ${EDIT} powerpc/ansi.h ## must remove __va_list, _BSD_VA_LIST 4774 4775Native builds *don't* work due to incompatibilities between native 4776and U-Boot include files. 4777 4778Booting assumes that (the first part of) the image booted is a 4779stage-2 loader which in turn loads and then invokes the kernel 4780proper. Loader sources will eventually appear in the NetBSD source 4781tree (probably in sys/arc/mpc8xx/stand/u-boot_stage2/); in the 4782meantime, see ftp://ftp.denx.de/pub/u-boot/ppcboot_stage2.tar.gz 4783 4784 4785Implementation Internals: 4786========================= 4787 4788The following is not intended to be a complete description of every 4789implementation detail. However, it should help to understand the 4790inner workings of U-Boot and make it easier to port it to custom 4791hardware. 4792 4793 4794Initial Stack, Global Data: 4795--------------------------- 4796 4797The implementation of U-Boot is complicated by the fact that U-Boot 4798starts running out of ROM (flash memory), usually without access to 4799system RAM (because the memory controller is not initialized yet). 4800This means that we don't have writable Data or BSS segments, and BSS 4801is not initialized as zero. To be able to get a C environment working 4802at all, we have to allocate at least a minimal stack. Implementation 4803options for this are defined and restricted by the CPU used: Some CPU 4804models provide on-chip memory (like the IMMR area on MPC8xx and 4805MPC826x processors), on others (parts of) the data cache can be 4806locked as (mis-) used as memory, etc. 4807 4808 Chris Hallinan posted a good summary of these issues to the 4809 U-Boot mailing list: 4810 4811 Subject: RE: [U-Boot-Users] RE: More On Memory Bank x (nothingness)? 4812 From: "Chris Hallinan" <clh@net1plus.com> 4813 Date: Mon, 10 Feb 2003 16:43:46 -0500 (22:43 MET) 4814 ... 4815 4816 Correct me if I'm wrong, folks, but the way I understand it 4817 is this: Using DCACHE as initial RAM for Stack, etc, does not 4818 require any physical RAM backing up the cache. The cleverness 4819 is that the cache is being used as a temporary supply of 4820 necessary storage before the SDRAM controller is setup. It's 4821 beyond the scope of this list to explain the details, but you 4822 can see how this works by studying the cache architecture and 4823 operation in the architecture and processor-specific manuals. 4824 4825 OCM is On Chip Memory, which I believe the 405GP has 4K. It 4826 is another option for the system designer to use as an 4827 initial stack/RAM area prior to SDRAM being available. Either 4828 option should work for you. Using CS 4 should be fine if your 4829 board designers haven't used it for something that would 4830 cause you grief during the initial boot! It is frequently not 4831 used. 4832 4833 CONFIG_SYS_INIT_RAM_ADDR should be somewhere that won't interfere 4834 with your processor/board/system design. The default value 4835 you will find in any recent u-boot distribution in 4836 walnut.h should work for you. I'd set it to a value larger 4837 than your SDRAM module. If you have a 64MB SDRAM module, set 4838 it above 400_0000. Just make sure your board has no resources 4839 that are supposed to respond to that address! That code in 4840 start.S has been around a while and should work as is when 4841 you get the config right. 4842 4843 -Chris Hallinan 4844 DS4.COM, Inc. 4845 4846It is essential to remember this, since it has some impact on the C 4847code for the initialization procedures: 4848 4849* Initialized global data (data segment) is read-only. Do not attempt 4850 to write it. 4851 4852* Do not use any uninitialized global data (or implicitly initialized 4853 as zero data - BSS segment) at all - this is undefined, initiali- 4854 zation is performed later (when relocating to RAM). 4855 4856* Stack space is very limited. Avoid big data buffers or things like 4857 that. 4858 4859Having only the stack as writable memory limits means we cannot use 4860normal global data to share information between the code. But it 4861turned out that the implementation of U-Boot can be greatly 4862simplified by making a global data structure (gd_t) available to all 4863functions. We could pass a pointer to this data as argument to _all_ 4864functions, but this would bloat the code. Instead we use a feature of 4865the GCC compiler (Global Register Variables) to share the data: we 4866place a pointer (gd) to the global data into a register which we 4867reserve for this purpose. 4868 4869When choosing a register for such a purpose we are restricted by the 4870relevant (E)ABI specifications for the current architecture, and by 4871GCC's implementation. 4872 4873For PowerPC, the following registers have specific use: 4874 R1: stack pointer 4875 R2: reserved for system use 4876 R3-R4: parameter passing and return values 4877 R5-R10: parameter passing 4878 R13: small data area pointer 4879 R30: GOT pointer 4880 R31: frame pointer 4881 4882 (U-Boot also uses R12 as internal GOT pointer. r12 4883 is a volatile register so r12 needs to be reset when 4884 going back and forth between asm and C) 4885 4886 ==> U-Boot will use R2 to hold a pointer to the global data 4887 4888 Note: on PPC, we could use a static initializer (since the 4889 address of the global data structure is known at compile time), 4890 but it turned out that reserving a register results in somewhat 4891 smaller code - although the code savings are not that big (on 4892 average for all boards 752 bytes for the whole U-Boot image, 4893 624 text + 127 data). 4894 4895On ARM, the following registers are used: 4896 4897 R0: function argument word/integer result 4898 R1-R3: function argument word 4899 R9: platform specific 4900 R10: stack limit (used only if stack checking is enabled) 4901 R11: argument (frame) pointer 4902 R12: temporary workspace 4903 R13: stack pointer 4904 R14: link register 4905 R15: program counter 4906 4907 ==> U-Boot will use R9 to hold a pointer to the global data 4908 4909 Note: on ARM, only R_ARM_RELATIVE relocations are supported. 4910 4911On Nios II, the ABI is documented here: 4912 http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf 4913 4914 ==> U-Boot will use gp to hold a pointer to the global data 4915 4916 Note: on Nios II, we give "-G0" option to gcc and don't use gp 4917 to access small data sections, so gp is free. 4918 4919On NDS32, the following registers are used: 4920 4921 R0-R1: argument/return 4922 R2-R5: argument 4923 R15: temporary register for assembler 4924 R16: trampoline register 4925 R28: frame pointer (FP) 4926 R29: global pointer (GP) 4927 R30: link register (LP) 4928 R31: stack pointer (SP) 4929 PC: program counter (PC) 4930 4931 ==> U-Boot will use R10 to hold a pointer to the global data 4932 4933NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope, 4934or current versions of GCC may "optimize" the code too much. 4935 4936On RISC-V, the following registers are used: 4937 4938 x0: hard-wired zero (zero) 4939 x1: return address (ra) 4940 x2: stack pointer (sp) 4941 x3: global pointer (gp) 4942 x4: thread pointer (tp) 4943 x5: link register (t0) 4944 x8: frame pointer (fp) 4945 x10-x11: arguments/return values (a0-1) 4946 x12-x17: arguments (a2-7) 4947 x28-31: temporaries (t3-6) 4948 pc: program counter (pc) 4949 4950 ==> U-Boot will use gp to hold a pointer to the global data 4951 4952Memory Management: 4953------------------ 4954 4955U-Boot runs in system state and uses physical addresses, i.e. the 4956MMU is not used either for address mapping nor for memory protection. 4957 4958The available memory is mapped to fixed addresses using the memory 4959controller. In this process, a contiguous block is formed for each 4960memory type (Flash, SDRAM, SRAM), even when it consists of several 4961physical memory banks. 4962 4963U-Boot is installed in the first 128 kB of the first Flash bank (on 4964TQM8xxL modules this is the range 0x40000000 ... 0x4001FFFF). After 4965booting and sizing and initializing DRAM, the code relocates itself 4966to the upper end of DRAM. Immediately below the U-Boot code some 4967memory is reserved for use by malloc() [see CONFIG_SYS_MALLOC_LEN 4968configuration setting]. Below that, a structure with global Board 4969Info data is placed, followed by the stack (growing downward). 4970 4971Additionally, some exception handler code is copied to the low 8 kB 4972of DRAM (0x00000000 ... 0x00001FFF). 4973 4974So a typical memory configuration with 16 MB of DRAM could look like 4975this: 4976 4977 0x0000 0000 Exception Vector code 4978 : 4979 0x0000 1FFF 4980 0x0000 2000 Free for Application Use 4981 : 4982 : 4983 4984 : 4985 : 4986 0x00FB FF20 Monitor Stack (Growing downward) 4987 0x00FB FFAC Board Info Data and permanent copy of global data 4988 0x00FC 0000 Malloc Arena 4989 : 4990 0x00FD FFFF 4991 0x00FE 0000 RAM Copy of Monitor Code 4992 ... eventually: LCD or video framebuffer 4993 ... eventually: pRAM (Protected RAM - unchanged by reset) 4994 0x00FF FFFF [End of RAM] 4995 4996 4997System Initialization: 4998---------------------- 4999 5000In the reset configuration, U-Boot starts at the reset entry point 5001(on most PowerPC systems at address 0x00000100). Because of the reset 5002configuration for CS0# this is a mirror of the on board Flash memory. 5003To be able to re-map memory U-Boot then jumps to its link address. 5004To be able to implement the initialization code in C, a (small!) 5005initial stack is set up in the internal Dual Ported RAM (in case CPUs 5006which provide such a feature like), or in a locked part of the data 5007cache. After that, U-Boot initializes the CPU core, the caches and 5008the SIU. 5009 5010Next, all (potentially) available memory banks are mapped using a 5011preliminary mapping. For example, we put them on 512 MB boundaries 5012(multiples of 0x20000000: SDRAM on 0x00000000 and 0x20000000, Flash 5013on 0x40000000 and 0x60000000, SRAM on 0x80000000). Then UPM A is 5014programmed for SDRAM access. Using the temporary configuration, a 5015simple memory test is run that determines the size of the SDRAM 5016banks. 5017 5018When there is more than one SDRAM bank, and the banks are of 5019different size, the largest is mapped first. For equal size, the first 5020bank (CS2#) is mapped first. The first mapping is always for address 50210x00000000, with any additional banks following immediately to create 5022contiguous memory starting from 0. 5023 5024Then, the monitor installs itself at the upper end of the SDRAM area 5025and allocates memory for use by malloc() and for the global Board 5026Info data; also, the exception vector code is copied to the low RAM 5027pages, and the final stack is set up. 5028 5029Only after this relocation will you have a "normal" C environment; 5030until that you are restricted in several ways, mostly because you are 5031running from ROM, and because the code will have to be relocated to a 5032new address in RAM. 5033 5034 5035U-Boot Porting Guide: 5036---------------------- 5037 5038[Based on messages by Jerry Van Baren in the U-Boot-Users mailing 5039list, October 2002] 5040 5041 5042int main(int argc, char *argv[]) 5043{ 5044 sighandler_t no_more_time; 5045 5046 signal(SIGALRM, no_more_time); 5047 alarm(PROJECT_DEADLINE - toSec (3 * WEEK)); 5048 5049 if (available_money > available_manpower) { 5050 Pay consultant to port U-Boot; 5051 return 0; 5052 } 5053 5054 Download latest U-Boot source; 5055 5056 Subscribe to u-boot mailing list; 5057 5058 if (clueless) 5059 email("Hi, I am new to U-Boot, how do I get started?"); 5060 5061 while (learning) { 5062 Read the README file in the top level directory; 5063 Read http://www.denx.de/twiki/bin/view/DULG/Manual; 5064 Read applicable doc/*.README; 5065 Read the source, Luke; 5066 /* find . -name "*.[chS]" | xargs grep -i <keyword> */ 5067 } 5068 5069 if (available_money > toLocalCurrency ($2500)) 5070 Buy a BDI3000; 5071 else 5072 Add a lot of aggravation and time; 5073 5074 if (a similar board exists) { /* hopefully... */ 5075 cp -a board/<similar> board/<myboard> 5076 cp include/configs/<similar>.h include/configs/<myboard>.h 5077 } else { 5078 Create your own board support subdirectory; 5079 Create your own board include/configs/<myboard>.h file; 5080 } 5081 Edit new board/<myboard> files 5082 Edit new include/configs/<myboard>.h 5083 5084 while (!accepted) { 5085 while (!running) { 5086 do { 5087 Add / modify source code; 5088 } until (compiles); 5089 Debug; 5090 if (clueless) 5091 email("Hi, I am having problems..."); 5092 } 5093 Send patch file to the U-Boot email list; 5094 if (reasonable critiques) 5095 Incorporate improvements from email list code review; 5096 else 5097 Defend code as written; 5098 } 5099 5100 return 0; 5101} 5102 5103void no_more_time (int sig) 5104{ 5105 hire_a_guru(); 5106} 5107 5108 5109Coding Standards: 5110----------------- 5111 5112All contributions to U-Boot should conform to the Linux kernel 5113coding style; see the kernel coding style guide at 5114https://www.kernel.org/doc/html/latest/process/coding-style.html, and the 5115script "scripts/Lindent" in your Linux kernel source directory. 5116 5117Source files originating from a different project (for example the 5118MTD subsystem) are generally exempt from these guidelines and are not 5119reformatted to ease subsequent migration to newer versions of those 5120sources. 5121 5122Please note that U-Boot is implemented in C (and to some small parts in 5123Assembler); no C++ is used, so please do not use C++ style comments (//) 5124in your code. 5125 5126Please also stick to the following formatting rules: 5127- remove any trailing white space 5128- use TAB characters for indentation and vertical alignment, not spaces 5129- make sure NOT to use DOS '\r\n' line feeds 5130- do not add more than 2 consecutive empty lines to source files 5131- do not add trailing empty lines to source files 5132 5133Submissions which do not conform to the standards may be returned 5134with a request to reformat the changes. 5135 5136 5137Submitting Patches: 5138------------------- 5139 5140Since the number of patches for U-Boot is growing, we need to 5141establish some rules. Submissions which do not conform to these rules 5142may be rejected, even when they contain important and valuable stuff. 5143 5144Please see http://www.denx.de/wiki/U-Boot/Patches for details. 5145 5146Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>; 5147see https://lists.denx.de/listinfo/u-boot 5148 5149When you send a patch, please include the following information with 5150it: 5151 5152* For bug fixes: a description of the bug and how your patch fixes 5153 this bug. Please try to include a way of demonstrating that the 5154 patch actually fixes something. 5155 5156* For new features: a description of the feature and your 5157 implementation. 5158 5159* A CHANGELOG entry as plaintext (separate from the patch) 5160 5161* For major contributions, add a MAINTAINERS file with your 5162 information and associated file and directory references. 5163 5164* When you add support for a new board, don't forget to add a 5165 maintainer e-mail address to the boards.cfg file, too. 5166 5167* If your patch adds new configuration options, don't forget to 5168 document these in the README file. 5169 5170* The patch itself. If you are using git (which is *strongly* 5171 recommended) you can easily generate the patch using the 5172 "git format-patch". If you then use "git send-email" to send it to 5173 the U-Boot mailing list, you will avoid most of the common problems 5174 with some other mail clients. 5175 5176 If you cannot use git, use "diff -purN OLD NEW". If your version of 5177 diff does not support these options, then get the latest version of 5178 GNU diff. 5179 5180 The current directory when running this command shall be the parent 5181 directory of the U-Boot source tree (i. e. please make sure that 5182 your patch includes sufficient directory information for the 5183 affected files). 5184 5185 We prefer patches as plain text. MIME attachments are discouraged, 5186 and compressed attachments must not be used. 5187 5188* If one logical set of modifications affects or creates several 5189 files, all these changes shall be submitted in a SINGLE patch file. 5190 5191* Changesets that contain different, unrelated modifications shall be 5192 submitted as SEPARATE patches, one patch per changeset. 5193 5194 5195Notes: 5196 5197* Before sending the patch, run the buildman script on your patched 5198 source tree and make sure that no errors or warnings are reported 5199 for any of the boards. 5200 5201* Keep your modifications to the necessary minimum: A patch 5202 containing several unrelated changes or arbitrary reformats will be 5203 returned with a request to re-formatting / split it. 5204 5205* If you modify existing code, make sure that your new code does not 5206 add to the memory footprint of the code ;-) Small is beautiful! 5207 When adding new features, these should compile conditionally only 5208 (using #ifdef), and the resulting code with the new feature 5209 disabled must not need more memory than the old code without your 5210 modification. 5211 5212* Remember that there is a size limit of 100 kB per message on the 5213 u-boot mailing list. Bigger patches will be moderated. If they are 5214 reasonable and not too big, they will be acknowledged. But patches 5215 bigger than the size limit should be avoided. 5216