1 menu "Command line interface"
4 bool "Support U-Boot commands"
7 Enable U-Boot's command-line functions. This provides a means
8 to enter commands into U-Boot for a wide variety of purposes. It
9 also allows scripts (containing commands) to be executed.
10 Various commands and command categorys can be indivdually enabled.
11 Depending on the number of commands enabled, this can add
12 substantially to the size of U-Boot.
18 This option enables the "hush" shell (from Busybox) as command line
19 interpreter, thus enabling powerful command line syntax like
20 if...then...else...fi conditionals or `&&' and '||'
21 constructs ("shell scripts").
23 If disabled, you get the old, much simpler behaviour with a somewhat
24 smaller memory footprint.
30 This string is displayed in the command line to the left of the
33 menu "Autoboot options"
39 This enables the autoboot. See doc/README.autoboot for detail.
42 bool "Stop autobooting via specific input key / string"
45 This option enables stopping (aborting) of the automatic
46 boot feature only by issuing a specific input key or
47 string. If not enabled, any input key will abort the
48 U-Boot automatic booting process and bring the device
49 to the U-Boot prompt for user input.
51 config AUTOBOOT_PROMPT
52 string "Autoboot stop prompt"
53 depends on AUTOBOOT_KEYED
54 default "Autoboot in %d seconds\\n"
56 This string is displayed before the boot delay selected by
57 CONFIG_BOOTDELAY starts. If it is not defined there is no
58 output indicating that autoboot is in progress.
60 Note that this define is used as the (only) argument to a
61 printf() call, so it may contain '%' format specifications,
62 provided that it also includes, sepearated by commas exactly
63 like in a printf statement, the required arguments. It is
64 the responsibility of the user to select only such arguments
65 that are valid in the given context.
67 config AUTOBOOT_ENCRYPTION
68 bool "Enable encryption in autoboot stopping"
69 depends on AUTOBOOT_KEYED
72 config AUTOBOOT_DELAY_STR
73 string "Delay autobooting via specific input key / string"
74 depends on AUTOBOOT_KEYED && !AUTOBOOT_ENCRYPTION
76 This option delays the automatic boot feature by issuing
77 a specific input key or string. If CONFIG_AUTOBOOT_DELAY_STR
78 or the environment variable "bootdelaykey" is specified
79 and this string is received from console input before
80 autoboot starts booting, U-Boot gives a command prompt. The
81 U-Boot prompt will time out if CONFIG_BOOT_RETRY_TIME is
82 used, otherwise it never times out.
84 config AUTOBOOT_STOP_STR
85 string "Stop autobooting via specific input key / string"
86 depends on AUTOBOOT_KEYED && !AUTOBOOT_ENCRYPTION
88 This option enables stopping (aborting) of the automatic
89 boot feature only by issuing a specific input key or
90 string. If CONFIG_AUTOBOOT_STOP_STR or the environment
91 variable "bootstopkey" is specified and this string is
92 received from console input before autoboot starts booting,
93 U-Boot gives a command prompt. The U-Boot prompt never
94 times out, even if CONFIG_BOOT_RETRY_TIME is used.
96 config AUTOBOOT_KEYED_CTRLC
97 bool "Enable Ctrl-C autoboot interruption"
98 depends on AUTOBOOT_KEYED && !AUTOBOOT_ENCRYPTION
101 This option allows for the boot sequence to be interrupted
102 by ctrl-c, in addition to the "bootdelaykey" and "bootstopkey".
103 Setting this variable provides an escape sequence from the
104 limited "password" strings.
106 config AUTOBOOT_STOP_STR_SHA256
107 string "Stop autobooting via SHA256 encrypted password"
108 depends on AUTOBOOT_KEYED && AUTOBOOT_ENCRYPTION
110 This option adds the feature to only stop the autobooting,
111 and therefore boot into the U-Boot prompt, when the input
112 string / password matches a values that is encypted via
113 a SHA256 hash and saved in the environment.
117 source "cmd/fastboot/Kconfig"
134 Print ".config" contents.
136 If this option is enabled, the ".config" file contents are embedded
137 in the U-Boot image and can be printed on the console by the "config"
138 command. This provides information of which options are enabled on
145 Print console devices and information.
150 Print information about available CPUs. This normally shows the
151 number of CPUs, type (e.g. manufacturer, architecture, product or
152 internal name) and clock frequency. Other information may be
153 available depending on the CPU driver.
159 Print GPL license text
169 Run the command stored in the environment "bootcmd", i.e.
170 "bootd" does the same thing as "run bootcmd".
176 Boot an application image from the memory.
181 Boot the Linux zImage
188 Boot an AArch64 Linux Kernel image from memory.
192 depends on EFI_LOADER
195 Boot an EFI image from memory.
197 config CMD_BOOTEFI_HELLO_COMPILE
198 bool "Compile a standard EFI hello world binary for testing"
199 depends on CMD_BOOTEFI && (ARM || X86)
202 This compiles a standard EFI hello world application with U-Boot so
203 that it can be used with the test/py testing framework. This is useful
204 for testing that EFI is working at a basic level, and for bringing
205 up EFI support on a new architecture.
207 No additional space will be required in the resulting U-Boot binary
208 when this option is enabled.
210 config CMD_BOOTEFI_HELLO
211 bool "Allow booting a standard EFI hello world for testing"
212 depends on CMD_BOOTEFI_HELLO_COMPILE
214 This adds a standard EFI hello world application to U-Boot so that
215 it can be used with the 'bootefi hello' command. This is useful
216 for testing that EFI is working at a basic level, and for bringing
217 up EFI support on a new architecture.
223 Add an ANSI terminal boot menu command.
226 bool "bootelf, bootvx"
229 Boot an ELF/vxWorks image from the memory.
232 bool "Flattened Device Tree utility commands"
236 Do FDT related setup before booting into the Operating System.
242 Start an application at a given address.
248 Run the command in the given environment variable.
254 Print header information for application image.
260 List all images found in flash
266 Extract a part of a multi-image.
271 Poweroff/Shutdown the system
275 menu "Environment commands"
278 bool "ask for env variable"
280 Ask for environment variable
298 Edit environment variable.
303 Allow for searching environment variables
309 Save all environment variables into the compiled-in persistent
312 config CMD_ENV_EXISTS
316 Check if a variable is defined in the environment for use in
319 config CMD_ENV_CALLBACK
320 bool "env callbacks - print callbacks and their associated variables"
322 Some environment variable have callbacks defined by
323 U_BOOT_ENV_CALLBACK. These are called when the variable changes.
324 For example changing "baudrate" adjust the serial baud rate. This
325 command lists the currently defined callbacks.
328 bool "env flags -print variables that have non-default flags"
330 Some environment variables have special flags that control their
331 behaviour. For example, serial# can only be written once and cannot
332 be deleted. This command shows the variables that have special
337 menu "Memory commands"
340 bool "md, mm, nm, mw, cp, cmp, base, loop"
345 mm - memory modify (auto-incrementing address)
346 nm - memory modify (constant address)
347 mw - memory write (fill)
350 base - print or set address offset
351 loop - initialize loop on address range
364 Add -v option to verify data against a crc32 checksum.
367 bool "eeprom - EEPROM subsystem"
369 (deprecated, needs conversion to driver model)
370 Provides commands to read and write EEPROM (Electrically Erasable
371 Programmable Read Only Memory) chips that are connected over an
374 config CMD_EEPROM_LAYOUT
375 bool "Enable layout-aware eeprom commands"
376 depends on CMD_EEPROM
378 (deprecated, needs conversion to driver model)
379 When enabled, additional eeprom sub-commands become available.
381 eeprom print - prints the contents of the eeprom in a human-readable
382 way (eeprom layout fields, and data formatted to be fit for human
385 eeprom update - allows user to update eeprom fields by specifying
386 the field name, and providing the new data in a human readable format
387 (same format as displayed by the eeprom print command).
389 Both commands can either auto detect the layout, or be told which
393 __weak int parse_layout_version(char *str)
394 - override to provide your own layout name parsing
395 __weak void __eeprom_layout_assign(struct eeprom_layout *layout,
397 - override to setup the layout metadata based on the version
398 __weak int eeprom_layout_detect(unsigned char *data)
399 - override to provide your own algorithm for detecting layout
402 - contains various printing and updating functions for common
403 types of eeprom fields. Can be used for defining
406 config EEPROM_LAYOUT_HELP_STRING
407 string "Tells user what layout names are supported"
408 depends on CMD_EEPROM_LAYOUT
409 default "<not defined>"
411 Help printed with the LAYOUT VERSIONS part of the 'eeprom'
419 Compute MD5 checksum.
424 depends on CMD_MD5SUM
426 Add -v option to verify data against an MD5 checksum.
432 Compute SHA1 checksum.
434 config SHA1SUM_VERIFY
436 depends on CMD_SHA1SUM
438 Add -v option to verify data against a SHA1 checksum.
443 Infinite write loop on address range
448 Simple RAM read/write test.
453 mdc - memory display cyclic
454 mwc - memory write cyclic
459 Display memory information.
463 menu "Compression commands"
469 Support decompressing an LZMA (Lempel-Ziv-Markov chain algorithm)
475 Uncompress a zip-compressed memory region.
480 Compress a memory region with zlib deflate method.
484 menu "Device access commands"
487 bool "clk - Show clock frequencies"
490 Shows clock frequences by calling a sock_clk_dump() hook function.
491 This is depreated in favour of using the CLK uclass and accessing
492 clock values from associated drivers. However currently no command
496 bool "dm - Access to driver model information"
500 Provides access to driver model data structures and information,
501 such as a list of devices, list of uclasses and the state of each
502 device (e.g. activated). This is not required for operation, but
503 can be useful to see the state of driver model for debugging or
507 bool "demo - Demonstration commands for driver model"
510 Provides a 'demo' command which can be used to play around with
511 driver model. To use this properly you will need to enable one or
512 both of the demo devices (DM_DEMO_SHAPE and DM_DEMO_SIMPLE).
513 Otherwise you will always get an empty list of devices. The demo
514 devices are defined in the sandbox device tree, so the easiest
515 option is to use sandbox and pass the -d point to sandbox's
519 bool "ide - Support for IDE drivers"
522 Provides an 'ide' command which allows accessing the IDE drive,
523 reseting the IDE interface, printing the partition table and
524 geting device info. It also enables the 'diskboot' command which
525 permits booting from an IDE drive.
528 bool "io - Support for performing I/O accesses"
530 Provides an 'iod' command to display I/O space and an 'iow' command
531 to write values to the I/O space. This can be useful for manually
532 checking the state of devices during boot when debugging device
536 bool "iotrace - Support for tracing I/O activity"
538 Provides an 'iotrace' command which supports recording I/O reads and
539 writes in a trace buffer in memory . It also maintains a checksum
540 of the trace records (even if space is exhausted) so that the
541 sequence of I/O accesses can be verified.
543 When debugging drivers it is useful to see what I/O accesses were
544 done and in what order.
546 Even if the individual accesses are of little interest it can be
547 useful to verify that the access pattern is consistent each time
548 an operation is performed. In this case a checksum can be used to
549 characterise the operation of a driver. The checksum can be compared
550 across different runs of the operation to verify that the driver is
553 In particular, when performing major refactoring of the driver, where
554 the access pattern should not change, the checksum provides assurance
555 that the refactoring work has not broken the driver.
557 This works by sneaking into the io.h heder for an architecture and
558 redirecting I/O accesses through iotrace's tracing mechanism.
560 For now no commands are provided to examine the trace buffer. The
561 format is fairly simple, so 'md' is a reasonable substitute.
563 Note: The checksum feature is only useful for I/O regions where the
564 contents do not change outside of software control. Where this is not
565 suitable you can fall back to manually comparing the addresses. It
566 might be useful to enhance tracing to only checksum the accesses and
567 not the data read/written.
573 Load a binary file over serial line.
579 Load an S-Record file over serial line
582 bool "flinfo, erase, protect"
586 flinfo - print FLASH memory information
588 protect - enable or disable FLASH write protection
591 bool "GPT (GUID Partition Table) command"
592 select PARTITION_UUIDS
595 Enable the 'gpt' command to ready and write GPT style partition
599 #depends on FLASH_CFI_DRIVER
602 ARM Ltd reference designs flash partition access
607 MMC memory mapped support.
611 default y if NAND_SUNXI
616 config CMD_NAND_TRIMFFS
617 bool "nand write.trimffs"
618 default y if ARCH_SUNXI
620 Allows one to skip empty pages when flashing something on a NAND.
622 config CMD_NAND_LOCK_UNLOCK
623 bool "nand lock/unlock"
625 NAND locking support.
627 config CMD_NAND_TORTURE
630 NAND torture support.
636 select PARTITION_UUIDS
638 Read and display information about the partition table on
663 select USB_FUNCTION_DFU
665 Enables the command "dfu" which is used to have U-Boot create a DFU
666 class device via USB.
668 config CMD_USB_MASS_STORAGE
669 bool "UMS usb mass storage"
671 USB mass storage support
679 config CMD_FPGA_LOADBP
680 bool "fpga loadbp - load partial bitstream (Xilinx only)"
683 Supports loading an FPGA device from a bitstream buffer containing
686 config CMD_FPGA_LOADFS
687 bool "fpga loadfs - load bitstream from FAT filesystem (Xilinx only)"
690 Supports loading an FPGA device from a FAT filesystem.
692 config CMD_FPGA_LOADMK
693 bool "fpga loadmk - load bitstream from image"
696 Supports loading an FPGA device from a image generated by mkimage.
698 config CMD_FPGA_LOADP
699 bool "fpga loadp - load partial bitstream"
702 Supports loading an FPGA device from a bitstream buffer containing
706 bool "fpgad - dump FPGA registers"
708 (legacy, needs conversion to driver model)
709 Provides a way to dump FPGA registers by calling the board-specific
710 fpga_get_reg() function. This functions similarly to the 'md'
714 bool "fuse - support for the fuse subssystem"
716 (deprecated - needs conversion to driver model)
717 This allows reading, sensing, programming or overriding fuses
718 which control the behaviour of the device. The command uses the
721 config CMD_REMOTEPROC
723 depends on REMOTEPROC
725 Support for Remote Processor control
733 bool "fdcboot - Boot from floppy device"
735 The 'fdtboot' command allows booting an image from a floppy disk.
740 menu "Shell scripting commands"
752 Return true/false on integer compare.
758 Run script from memory
764 Evaluate boolean and math expressions and store the result in an env
766 Also supports loading the value at a memory location into a variable.
767 If CONFIG_REGEX is enabled, setexpr also supports a gsub function.
771 menu "Network commands"
774 bool "bootp, tftpboot"
779 bootp - boot image via network using BOOTP/TFTP protocol
780 tftpboot - boot image via network using TFTP protocol
785 TFTP put command, for uploading files to a server
790 Act as a TFTP server and boot the first received file
795 Boot image via network using RARP/TFTP protocol
800 Boot image via network using DHCP/TFTP protocol
806 Boot image via network using PXE protocol
812 Boot image via network using NFS protocol.
817 Enable MII utility commands.
822 Send ICMP ECHO_REQUEST to network host
827 Perform CDP network configuration
832 Synchronize RTC via network
837 Lookup the IP of a hostname
839 config CMD_LINK_LOCAL
842 Acquire a network IP address using the link-local protocol
847 Allow control of L2 Ethernet switch commands. These are supported
848 by the vsc9953 Ethernet driver at present. Sub-commands allow
849 operations such as enabling / disabling a port and
850 viewing/maintaining the filtering database (FDB)
857 bool "Enable 'bmp' command"
858 depends on LCD || DM_VIDEO || VIDEO
860 This provides a way to obtain information about a BMP-format iamge
861 and to display it. BMP (which presumably stands for BitMaP) is a
862 file format defined by Microsoft which supports images of various
863 depths, formats and compression methods. Headers on the file
864 determine the formats used. This command can be used by first loading
865 the image into RAM, then using this command to look at it or display
869 bool "Enable board-specific commands"
871 (deprecated: instead, please define a Kconfig option for each command)
873 Some boards have board-specific commands which are only enabled
874 during developemnt and need to be turned off for production. This
875 option provides a way to control this. The commands that are enabled
876 vary depending on the board.
878 config CMD_BKOPS_ENABLE
879 bool "mmc bkops enable"
883 Enable command for setting manual background operations handshake
884 on a eMMC device. The feature is optionally available on eMMC devices
885 conforming to standard >= 4.41.
887 config CMD_BLOCK_CACHE
888 bool "blkcache - control and stats for block cache"
889 depends on BLOCK_CACHE
890 default y if BLOCK_CACHE
892 Enable the blkcache command, which can be used to control the
893 operation of the cache functions.
894 This is most useful when fine-tuning the operation of the cache
895 during development, but also allows the cache to be disabled when
896 it might hurt performance (e.g. when using the ums command).
899 bool "icache or dcache"
901 Enable the "icache" and "dcache" commands
904 bool "Enable the 'display' command, for character displays"
906 (this needs porting to driver model)
907 This enables the 'display' command which allows a string to be
908 displayed on a simple board-specific display. Implement
909 display_putc() to use it.
915 Enable the 'led' command which allows for control of LEDs supported
916 by the board. The LEDs can be listed with 'led list' and controlled
917 with led on/off/togle/blink. Any LED drivers can be controlled with
918 this command, e.g. led_gpio.
924 Enable the 'date' command for getting/setting the time/date in RTC
930 Run commands and summarize execution time.
933 bool "gettime - read elapsed time"
935 Enable the 'gettime' command which reads the elapsed time since
936 U-Boot started running. This shows the time in seconds and
937 milliseconds. See also the 'bootstage' command which provides more
938 flexibility for boot timing.
940 # TODO: rename to CMD_SLEEP
945 Delay execution for some time
950 Access the system timer.
956 This provides basic access to the U-Boot's sound support. The main
957 feature is to play a beep.
959 sound init - set up sound system
960 sound play - play a sound
966 This provides access to the QEMU firmware interface. The main
967 feature is to allow easy loading of files passed to qemu-system
968 via -kernel / -initrd
970 source "cmd/mvebu/Kconfig"
975 bool "Enable the 'bootstage' command"
978 Add a 'bootstage' command which supports printing a report
979 and un/stashing of bootstage data.
981 menu "Power commands"
983 bool "Enable Driver Model PMIC command"
986 This is the pmic command, based on a driver model pmic's API.
987 Command features are unchanged:
988 - list - list pmic devices
989 - pmic dev <id> - show or [set] operating pmic device (NEW)
990 - pmic dump - dump registers
991 - pmic read address - read byte of register at address
992 - pmic write address - write byte to register at address
993 The only one change for this command is 'dev' subcommand.
996 bool "Enable Driver Model REGULATOR command"
997 depends on DM_REGULATOR
999 This command is based on driver model regulator's API.
1000 User interface features:
1001 - list - list regulator devices
1002 - regulator dev <id> - show or [set] operating regulator device
1003 - regulator info - print constraints info
1004 - regulator status - print operating status
1005 - regulator value <val] <-f> - print/[set] voltage value [uV]
1006 - regulator current <val> - print/[set] current value [uA]
1007 - regulator mode <id> - print/[set] operating mode id
1008 - regulator enable - enable the regulator output
1009 - regulator disable - disable the regulator output
1011 The '-f' (force) option can be used for set the value which exceeds
1012 the limits, which are found in device-tree and are kept in regulator's
1013 uclass platdata structure.
1017 menu "Security commands"
1019 bool "Enable the 'aes' command"
1022 This provides a means to encrypt and decrypt data using the AES
1023 (Advanced Encryption Standard). This algorithm uses a symetric key
1024 and is widely used as a streaming cipher. Different key lengths are
1025 supported by the algorithm but this command only supports 128 bits
1029 bool "Enable the 'blob' command"
1031 This is used with the Freescale secure boot mechanism.
1033 Freescale's SEC block has built-in Blob Protocol which provides
1034 a method for protecting user-defined data across system power
1035 cycles. SEC block protects data in a data structure called a Blob,
1036 which provides both confidentiality and integrity protection.
1038 Encapsulating data as a blob
1039 Each time that the Blob Protocol is used to protect data, a
1040 different randomly generated key is used to encrypt the data.
1041 This random key is itself encrypted using a key which is derived
1042 from SoC's non-volatile secret key and a 16 bit Key identifier.
1043 The resulting encrypted key along with encrypted data is called a
1044 blob. The non-volatile secure key is available for use only during
1047 During decapsulation, the reverse process is performed to get back
1051 blob enc - encapsulating data as a cryptgraphic blob
1052 blob dec - decapsulating cryptgraphic blob to get the data
1056 blob enc src dst len km
1058 Encapsulate and create blob of data $len bytes long
1059 at address $src and store the result at address $dst.
1060 $km is the 16 byte key modifier is also required for
1061 generation/use as key for cryptographic operation. Key
1062 modifier should be 16 byte long.
1064 blob dec src dst len km
1066 Decapsulate the blob of data at address $src and
1067 store result of $len byte at addr $dst.
1068 $km is the 16 byte key modifier is also required for
1069 generation/use as key for cryptographic operation. Key
1070 modifier should be 16 byte long.
1073 bool "Support 'hash' command"
1076 This provides a way to hash data in memory using various supported
1077 algorithms (such as SHA1, MD5, CRC32). The computed digest can be
1078 saved to memory or to an environment variable. It is also possible
1079 to verify a hash against data in memory.
1085 Add -v option to verify data against a hash.
1088 bool "Enable the 'tpm' command"
1091 This provides a means to talk to a TPM from the command line. A wide
1092 range of commands if provided - see 'tpm help' for details. The
1093 command requires a suitable TPM on your board and the correct driver
1097 bool "Enable the 'tpm test' command"
1100 This provides a a series of tests to confirm that the TPM is working
1101 correctly. The tests cover initialisation, non-volatile RAM, extend,
1102 global lock and checking that timing is within expectations. The
1103 tests pass correctly on Infineon TPMs but may need to be adjusted
1108 menu "Firmware commands"
1110 bool "Enable crosec command"
1114 Enable command-line access to the Chrome OS EC (Embedded
1115 Controller). This provides the 'crosec' command which has
1116 a number of sub-commands for performing EC tasks such as
1117 updating its flash, accessing a small saved context area
1118 and talking to the I2C bus behind the EC (if there is one).
1121 menu "Filesystem commands"
1123 bool "Enable the 'cbfs' command"
1126 Define this to enable support for reading from a Coreboot
1127 filesystem. This is a ROM-based filesystem used for accessing files
1128 on systems that use coreboot as the first boot-loader and then load
1129 U-Boot to actually boot the Operating System. Available commands are
1130 cbfsinit, cbfsinfo, cbfsls and cbfsload.
1133 bool "Enable the 'cramfs' command"
1134 depends on FS_CRAMFS
1136 This provides commands for dealing with CRAMFS (Compressed ROM
1137 filesystem). CRAMFS is useful when space is tight since files are
1138 compressed. Two commands are provided:
1140 cramfsls - lists files in a cramfs image
1141 cramfsload - loads a file from a cramfs image
1144 bool "ext2 command support"
1146 Enables EXT2 FS command
1149 bool "ext4 command support"
1151 Enables EXT4 FS command
1153 config CMD_EXT4_WRITE
1155 bool "ext4 write command support"
1157 Enables EXT4 FS write command
1160 bool "FAT command support"
1163 Support for the FAT fs
1165 config CMD_FS_GENERIC
1166 bool "filesystem commands"
1168 Enables filesystem commands (e.g. load, ls) that work for multiple
1172 bool "fsuuid command"
1174 Enables fsuuid command for filesystem UUID.
1177 bool "jffs2 command"
1180 Enables commands to support the JFFS2 (Journalling Flash File System
1181 version 2) filesystem. This enables fsload, ls and fsinfo which
1182 provide the ability to load files, list directories and obtain
1183 filesystem information.
1186 depends on ARCH_SUNXI
1187 bool "MTD partition support"
1189 MTD partition support
1191 config MTDIDS_DEFAULT
1192 string "Default MTD IDs"
1193 depends on CMD_MTDPARTS
1195 Defines a default MTD ID
1197 config MTDPARTS_DEFAULT
1198 string "Default MTD partition scheme"
1199 depends on CMD_MTDPARTS
1201 Defines a default MTD partitioning scheme in the Linux MTD command
1202 line partitions format
1206 menu "Debug commands"
1211 The bedbug (emBEDded deBUGger) command provides debugging features
1212 for some PowerPC processors. For details please see the
1213 docuemntation in doc/README.beddbug
1216 bool "diag - Board diagnostics"
1218 This command provides access to board diagnostic tests. These are
1219 called Power-on Self Tests (POST). The command allows listing of
1220 available tests and running either all the tests, or specific tests
1224 bool "irq - Show information about interrupts"
1225 depends on !ARM && !MIPS && !SH
1227 This enables two commands:
1229 interrupts - enable or disable interrupts
1230 irqinfo - print device-specific interrupt information
1233 bool "kgdb - Allow debugging of U-Boot with gdb"
1235 This enables a 'kgdb' command which allows gdb to connect to U-Boot
1236 over a serial link for debugging purposes. This allows
1237 single-stepping, inspecting variables, etc. This is supported only
1238 on PowerPC at present.
1243 tristate "Enable UBI - Unsorted block images commands"
1246 default y if NAND_SUNXI
1248 UBI is a software layer above MTD layer which admits use of LVM-like
1249 logical volumes on top of MTD devices, hides some complexities of
1250 flash chips like wear and bad blocks and provides some other useful
1251 capabilities. Please, consult the MTD web site for more details
1252 (www.linux-mtd.infradead.org). Activate this option if you want
1253 to use U-Boot UBI commands.
1256 tristate "Enable UBIFS - Unsorted block images filesystem commands"
1259 select RBTREE if ARCH_SUNXI
1260 select LZO if ARCH_SUNXI
1261 default y if NAND_SUNXI
1263 UBIFS is a file system for flash devices which works on top of UBI.