who contributed the specific port. The MAINTAINERS file lists board
maintainers.
+Note: There is no CHANGELOG file in the actual U-Boot source tree;
+it can be created dynamically from the Git log using:
+
+ make CHANGELOG
+
Where to get help:
==================
Thumb2 this flag will result in Thumb2 code generated by
GCC.
+ CONFIG_ARM_ERRATA_716044
+ CONFIG_ARM_ERRATA_742230
+ CONFIG_ARM_ERRATA_743622
+ CONFIG_ARM_ERRATA_751472
+
+ If set, the workarounds for these ARM errata are applied early
+ during U-Boot startup. Note that these options force the
+ workarounds to be applied; no CPU-type/version detection
+ exists, unlike the similar options in the Linux kernel. Do not
+ set these options unless they apply!
+
- Linux Kernel Interface:
CONFIG_CLOCKS_IN_MHZ
boot loader that has already initialized the UART. Define this
variable to flush the UART at init time.
+ CONFIG_SYS_NS16550_BROKEN_TEMT
+
+ 16550 UART set the Transmitter Empty (TEMT) Bit when all output
+ has finished and the transmitter is totally empty. U-Boot waits
+ for this bit to be set to initialize the serial console. On some
+ broken platforms this bit is not set in SPL making U-Boot to
+ hang while waiting for TEMT. Define this option to avoid it.
+
- Console Interface:
Depending on board, define exactly one serial port
CONFIG_CMD_EDITENV edit env variable
CONFIG_CMD_EEPROM * EEPROM read/write support
CONFIG_CMD_ELF * bootelf, bootvx
+ CONFIG_CMD_ENV_CALLBACK * display details about env callbacks
+ CONFIG_CMD_ENV_FLAGS * display details about env flags
CONFIG_CMD_EXPORTENV * export the environment
CONFIG_CMD_EXT2 * ext2 command support
CONFIG_CMD_EXT4 * ext4 command support
CONFIG_CMD_FDOS * Dos diskette Support
CONFIG_CMD_FLASH flinfo, erase, protect
CONFIG_CMD_FPGA FPGA device initialization support
+ CONFIG_CMD_GETTIME * Get time since boot
CONFIG_CMD_GO * the 'go' command (exec code)
CONFIG_CMD_GREPENV * search environment
+ CONFIG_CMD_HASH * calculate hash / digest
CONFIG_CMD_HWFLOW * RTS/CTS hw flow control
CONFIG_CMD_I2C * I2C serial bus support
CONFIG_CMD_IDE * IDE harddisk support
CONFIG_CMD_IMI iminfo
- CONFIG_CMD_IMLS List all found images
+ CONFIG_CMD_IMLS List all images found in NOR flash
+ CONFIG_CMD_IMLS_NAND List all images found in NAND flash
CONFIG_CMD_IMMAP * IMMR dump support
CONFIG_CMD_IMPORTENV * import an environment
CONFIG_CMD_INI * import data from an ini file into the env
CONFIG_CMD_LOADS loads
CONFIG_CMD_MD5SUM print md5 message digest
(requires CONFIG_CMD_MEMORY and CONFIG_MD5)
+ CONFIG_CMD_MEMINFO * Display detailed memory information
CONFIG_CMD_MEMORY md, mm, nm, mw, cp, cmp, crc, base,
- loop, loopw, mtest
+ loop, loopw
+ CONFIG_CMD_MEMTEST mtest
CONFIG_CMD_MISC Misc functions like sleep etc
CONFIG_CMD_MMC * MMC memory mapped support
CONFIG_CMD_MII * MII utility commands
CONFIG_CMD_PING * send ICMP ECHO_REQUEST to network
host
CONFIG_CMD_PORTIO * Port I/O
+ CONFIG_CMD_READ * Read raw data from partition
CONFIG_CMD_REGINFO * Register dump
CONFIG_CMD_RUN run command in env variable
+ CONFIG_CMD_SANDBOX * sb command to access sandbox features
CONFIG_CMD_SAVES * save S record dump
CONFIG_CMD_SCSI * SCSI Support
CONFIG_CMD_SDRAM * print SDRAM configuration information
boot. See the documentation file README.video for a
description of this variable.
+ CONFIG_VIDEO_VGA
+
+ Enable the VGA video / BIOS for x86. The alternative if you
+ are using coreboot is to use the coreboot frame buffer
+ driver.
+
+
- Keyboard Support:
CONFIG_KEYBOARD
Normally display is black on white background; define
CONFIG_SYS_WHITE_ON_BLACK to get it inverted.
+ CONFIG_LCD_ALIGNMENT
+
+ Normally the LCD is page-aligned (tyically 4KB). If this is
+ defined then the LCD will be aligned to this value instead.
+ For ARM it is sometimes useful to use MMU_SECTION_SIZE
+ here, since it is cheaper to change data cache settings on
+ a per-section basis.
+
+ CONFIG_CONSOLE_SCROLL_LINES
+
+ When the console need to be scrolled, this is the number of
+ lines to scroll by. It defaults to 1. Increasing this makes
+ the console jump but can help speed up operation when scrolling
+ is slow.
+
CONFIG_LCD_BMP_RLE8
Support drawing of RLE8-compressed bitmaps on the LCD.
+ CONFIG_I2C_EDID
+
+ Enables an 'i2c edid' command which can read EDID
+ information over I2C from an attached LCD display.
- Splash Screen Support: CONFIG_SPLASH_SCREEN
allows for a "silent" boot where a splash screen is
loaded very quickly after power-on.
+ CONFIG_SPLASHIMAGE_GUARD
+
+ If this option is set, then U-Boot will prevent the environment
+ variable "splashimage" from being set to a problematic address
+ (see README.displaying-bmps and README.arm-unaligned-accesses).
+ This option is useful for targets where, due to alignment
+ restrictions, an improperly aligned BMP image will cause a data
+ abort. If you think you will not have problems with unaligned
+ accesses (for example because your toolchain prevents them)
+ there is no need to set this option.
+
CONFIG_SPLASH_SCREEN_ALIGN
If this option is set the splash image can be freely positioned
=> vertically centered image
at x = dspWidth - bmpWidth - 9
+ CONFIG_SPLASH_SCREEN_PREPARE
+
+ If this option is set then the board_splash_screen_prepare()
+ function, which must be defined in your code, is called as part
+ of the splash screen display sequence. It gives the board an
+ opportunity to prepare the splash image data before it is
+ processed and sent to the frame buffer by U-Boot.
+
- Gzip compressed BMP image support: CONFIG_VIDEO_BMP_GZIP
If this option is set, additionally to standard BMP
serial# is unaffected by this, i. e. it remains
read-only.]
+ The same can be accomplished in a more flexible way
+ for any variable by configuring the type of access
+ to allow for those variables in the ".flags" variable
+ or define CONFIG_ENV_FLAGS_LIST_STATIC.
+
- Protected RAM:
CONFIG_PRAM
HERMES, IP860, RPXlite, LWMON,
FLAGADM, TQM8260
+- Access to physical memory region (> 4GB)
+ Some basic support is provided for operations on memory not
+ normally accessible to U-Boot - e.g. some architectures
+ support access to more than 4GB of memory on 32-bit
+ machines using physical address extension or similar.
+ Define CONFIG_PHYSMEM to access this basic support, which
+ currently only supports clearing the memory.
+
- Error Recovery:
CONFIG_PANIC_HANG
run-time determined information about the hardware to the
environment. These will be named board_name, board_rev.
+ CONFIG_DELAY_ENVIRONMENT
+
+ Normally the environment is loaded when the board is
+ intialised so that it is available to U-Boot. This inhibits
+ that so that the environment is not available until
+ explicitly loaded later by U-Boot code. With CONFIG_OF_CONTROL
+ this is instead controlled by the value of
+ /config/load-environment.
+
- DataFlash Support:
CONFIG_HAS_DATAFLASH
CONFIG_SF_DEFAULT_MODE (see include/spi.h)
CONFIG_SF_DEFAULT_SPEED in Hz
+ CONFIG_CMD_SF_TEST
+
+ Define this option to include a destructive SPI flash
+ test ('sf test').
+
- SystemACE Support:
CONFIG_SYSTEMACE
A better solution is to properly configure the firewall,
but sometimes that is not allowed.
+- Hashing support:
+ CONFIG_CMD_HASH
+
+ This enables a generic 'hash' command which can produce
+ hashes / digests from a few algorithms (e.g. SHA1, SHA256).
+
+ CONFIG_HASH_VERIFY
+
+ Enable the hash verify command (hash -v). This adds to code
+ size a little.
+
+ CONFIG_SHA1 - support SHA1 hashing
+ CONFIG_SHA256 - support SHA256 hashing
+
+ Note: There is also a sha1sum command, which should perhaps
+ be deprecated in favour of 'hash sha1'.
+
- Show boot progress:
CONFIG_SHOW_BOOT_PROGRESS
-150 common/cmd_nand.c Incorrect FIT image format
151 common/cmd_nand.c FIT image format OK
+- FIT image support:
+ CONFIG_FIT
+ Enable support for the FIT uImage format.
+
+ CONFIG_FIT_BEST_MATCH
+ When no configuration is explicitly selected, default to the
+ one whose fdt's compatibility field best matches that of
+ U-Boot itself. A match is considered "best" if it matches the
+ most specific compatibility entry of U-Boot's fdt's root node.
+ The order of entries in the configuration's fdt is ignored.
+
- Standalone program support:
CONFIG_STANDALONE_LOAD_ADDR
CONFIG_FB_ADDR
Define CONFIG_FB_ADDR if you want to use specific
- address for frame buffer.
- Then system will reserve the frame buffer address to
- defined address instead of lcd_setmem (this function
- grabs the memory for frame buffer by panel's size).
+ address for frame buffer. This is typically the case
+ when using a graphics controller has separate video
+ memory. U-Boot will then place the frame buffer at
+ the given address instead of dynamically reserving it
+ in system RAM by calling lcd_setmem(), which grabs
+ the memory for the frame buffer depending on the
+ configured panel size.
Please see board_init_f function.
CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
Filename to read to load U-Boot when reading from FAT
+ CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
+ Set this for NAND SPL on PPC mpc83xx targets, so that
+ start.S waits for the rest of the SPL to load before
+ continuing (the hardware starts execution after just
+ loading the first page rather than the full 4K).
+
+ CONFIG_SPL_NAND_BASE
+ Include nand_base.c in the SPL. Requires
+ CONFIG_SPL_NAND_DRIVERS.
+
+ CONFIG_SPL_NAND_DRIVERS
+ SPL uses normal NAND drivers, not minimal drivers.
+
+ CONFIG_SPL_NAND_ECC
+ Include standard software ECC in the SPL
+
CONFIG_SPL_NAND_SIMPLE
- Support for drivers/mtd/nand/libnand.o in SPL binary
+ Support for NAND boot using simple NAND drivers that
+ expose the cmd_ctrl() interface.
CONFIG_SYS_NAND_5_ADDR_CYCLE, CONFIG_SYS_NAND_PAGE_COUNT,
CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE,
CONFIG_SYS_NAND_ECCPOS, CONFIG_SYS_NAND_ECCSIZE,
CONFIG_SYS_NAND_ECCBYTES
Defines the size and behavior of the NAND that SPL uses
- to read U-Boot with CONFIG_SPL_NAND_SIMPLE
+ to read U-Boot
CONFIG_SYS_NAND_U_BOOT_OFFS
- Location in NAND for CONFIG_SPL_NAND_SIMPLE to read U-Boot
- from.
+ Location in NAND to read U-Boot from
+
+ CONFIG_SYS_NAND_U_BOOT_DST
+ Location in memory to load U-Boot to
+
+ CONFIG_SYS_NAND_U_BOOT_SIZE
+ Size of image to load
CONFIG_SYS_NAND_U_BOOT_START
- Location in memory for CONFIG_SPL_NAND_SIMPLE to load U-Boot
- to.
+ Entry point in loaded image to jump to
CONFIG_SYS_NAND_HW_ECC_OOBFIRST
Define this if you need to first read the OOB and then the
CONFIG_SPL_LIBGENERIC_SUPPORT
Support for lib/libgeneric.o in SPL binary
+ CONFIG_SPL_PAD_TO
+ Linker address to which the SPL should be padded before
+ appending the SPL payload.
+
CONFIG_SPL_TARGET
Final target image containing SPL and payload. Some SPLs
use an arch-specific makefile fragment instead, for
non page size aligned address and this could cause major
problems.
-- CONFIG_SYS_TFTP_LOADADDR:
- Default load address for network file downloads
-
- CONFIG_SYS_LOADS_BAUD_CHANGE:
Enable temporary baudrate change while serial download
cases. This setting can be used to tune behaviour; see
lib/hashtable.c for details.
+- CONFIG_ENV_FLAGS_LIST_DEFAULT
+- CONFIG_ENV_FLAGS_LIST_STATIC
+ Enable validation of the values given to enviroment variables when
+ calling env set. Variables can be restricted to only decimal,
+ hexadecimal, or boolean. If CONFIG_CMD_NET is also defined,
+ the variables can also be restricted to IP address or MAC address.
+
+ The format of the list is:
+ type_attribute = [s|d|x|b|i|m]
+ access_atribute = [a|r|o|c]
+ attributes = type_attribute[access_atribute]
+ entry = variable_name[:attributes]
+ list = entry[,list]
+
+ The type attributes are:
+ s - String (default)
+ d - Decimal
+ x - Hexadecimal
+ b - Boolean ([1yYtT|0nNfF])
+ i - IP address
+ m - MAC address
+
+ The access attributes are:
+ a - Any (default)
+ r - Read-only
+ o - Write-once
+ c - Change-default
+
+ - CONFIG_ENV_FLAGS_LIST_DEFAULT
+ Define this to a list (string) to define the ".flags"
+ envirnoment variable in the default or embedded environment.
+
+ - CONFIG_ENV_FLAGS_LIST_STATIC
+ Define this to a list (string) to define validation that
+ should be done if an entry is not found in the ".flags"
+ environment variable. To override a setting in the static
+ list, simply add an entry for the same variable name to the
+ ".flags" variable.
+
+- CONFIG_ENV_ACCESS_IGNORE_FORCE
+ If defined, don't allow the -f switch to env set override variable
+ access flags.
+
+- CONFIG_SYS_GENERIC_BOARD
+ This selects the architecture-generic board system instead of the
+ architecture-specific board files. It is intended to move boards
+ to this new framework over time. Defining this will disable the
+ arch/foo/lib/board.c file and use common/board_f.c and
+ common/board_r.c instead. To use this option your architecture
+ must support it (i.e. must define __HAVE_ARCH_GENERIC_BOARD in
+ its config.mk file). If you find problems enabling this option on
+ your board please report the problem and send patches!
+
+- CONFIG_SYS_SYM_OFFSETS
+ This is set by architectures that use offsets for link symbols
+ instead of absolute values. So bss_start is obtained using an
+ offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
+ directly. You should not need to touch this setting.
+
+
The following definitions that deal with the placement and management
of environment data (variable area); in general, we support the
following configurations:
space for already greatly restricted images, including but not
limited to NAND_SPL configurations.
+- CONFIG_DISPLAY_BOARDINFO
+ Display information about the board that U-Boot is running on
+ when U-Boot starts up. The board function checkboard() is called
+ to do this.
+
+- CONFIG_DISPLAY_BOARDINFO_LATE
+ Similar to the previous option, but display this information
+ later, once stdio is running and output goes to the LCD, if
+ present.
+
Low Level (hardware related) configuration options:
---------------------------------------------------
that is executed before the actual U-Boot. E.g. when
compiling a NAND SPL.
+- CONFIG_ARCH_MAP_SYSMEM
+ Generally U-Boot (and in particular the md command) uses
+ effective address. It is therefore not necessary to regard
+ U-Boot address as virtual addresses that need to be translated
+ to physical addresses. However, sandbox requires this, since
+ it maintains its own little RAM buffer which contains all
+ addressable memory. This option causes some memory accesses
+ to be mapped through map_sysmem() / unmap_sysmem().
+
- CONFIG_USE_ARCH_MEMCPY
CONFIG_USE_ARCH_MEMSET
If these options are used a optimized version of memcpy/memset will
be used if available. These functions may be faster under some
conditions but may increase the binary size.
+- CONFIG_X86_RESET_VECTOR
+ If defined, the x86 reset vector code is included. This is not
+ needed when U-Boot is running from Coreboot.
+
+- CONFIG_SYS_MPUCLK
+ Defines the MPU clock speed (in MHz).
+
+ NOTE : currently only supported on AM335x platforms.
+
Freescale QE/FMAN Firmware Support:
-----------------------------------
protect - enable or disable FLASH write protection
erase - erase FLASH memory
flinfo - print FLASH memory information
+nand - NAND memory operations (see doc/README.nand)
bdinfo - print Board Info structure
iminfo - print header information for application image
coninfo - print console devices and informations
only effect after the next boot (yes, that's just like Windoze :-).
+Callback functions for environment variables:
+---------------------------------------------
+
+For some environment variables, the behavior of u-boot needs to change
+when their values are changed. This functionailty allows functions to
+be associated with arbitrary variables. On creation, overwrite, or
+deletion, the callback will provide the opportunity for some side
+effect to happen or for the change to be rejected.
+
+The callbacks are named and associated with a function using the
+U_BOOT_ENV_CALLBACK macro in your board or driver code.
+
+These callbacks are associated with variables in one of two ways. The
+static list can be added to by defining CONFIG_ENV_CALLBACK_LIST_STATIC
+in the board configuration to a string that defines a list of
+associations. The list must be in the following format:
+
+ entry = variable_name[:callback_name]
+ list = entry[,list]
+
+If the callback name is not specified, then the callback is deleted.
+Spaces are also allowed anywhere in the list.
+
+Callbacks can also be associated by defining the ".callbacks" variable
+with the same list format above. Any association in ".callbacks" will
+override any association in the static list. You can define
+CONFIG_ENV_CALLBACK_LIST_DEFAULT to a list (string) to define the
+".callbacks" envirnoment variable in the default or embedded environment.
+
+
Command Line Parsing:
=====================