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.
26 config CMDLINE_EDITING
27 bool "Enable command line editing"
31 Enable editing and History functions for interactive command line
35 bool "Enable auto complete using TAB"
39 Enable auto completion of commands using TAB.
42 bool "Enable long help messages"
46 Defined when you want long help messages included
47 Do not set this option when short of memory.
51 default "Zynq> " if ARCH_ZYNQ
52 default "ZynqMP> " if ARCH_ZYNQMP
55 This string is displayed in the command line to the left of the
59 string "Command execution tracer"
63 This option enables the possiblity to print all commands before
64 executing them and after all variables are evaluated (similar
65 to Bash's xtrace/'set -x' feature).
66 To enable the tracer a variable "xtrace" needs to be defined in
69 menu "Autoboot options"
75 This enables the autoboot. See doc/README.autoboot for detail.
78 bool "Stop autobooting via specific input key / string"
81 This option enables stopping (aborting) of the automatic
82 boot feature only by issuing a specific input key or
83 string. If not enabled, any input key will abort the
84 U-Boot automatic booting process and bring the device
85 to the U-Boot prompt for user input.
87 config AUTOBOOT_PROMPT
88 string "Autoboot stop prompt"
89 depends on AUTOBOOT_KEYED
90 default "Autoboot in %d seconds\\n"
92 This string is displayed before the boot delay selected by
93 CONFIG_BOOTDELAY starts. If it is not defined there is no
94 output indicating that autoboot is in progress.
96 Note that this define is used as the (only) argument to a
97 printf() call, so it may contain '%' format specifications,
98 provided that it also includes, sepearated by commas exactly
99 like in a printf statement, the required arguments. It is
100 the responsibility of the user to select only such arguments
101 that are valid in the given context.
103 config AUTOBOOT_ENCRYPTION
104 bool "Enable encryption in autoboot stopping"
105 depends on AUTOBOOT_KEYED
107 This option allows a string to be entered into U-Boot to stop the
108 autoboot. The string itself is hashed and compared against the hash
109 in the environment variable 'bootstopkeysha256'. If it matches then
110 boot stops and a command-line prompt is presented.
112 This provides a way to ship a secure production device which can also
113 be accessed at the U-Boot command line.
115 config AUTOBOOT_DELAY_STR
116 string "Delay autobooting via specific input key / string"
117 depends on AUTOBOOT_KEYED && !AUTOBOOT_ENCRYPTION
119 This option delays the automatic boot feature by issuing
120 a specific input key or string. If CONFIG_AUTOBOOT_DELAY_STR
121 or the environment variable "bootdelaykey" is specified
122 and this string is received from console input before
123 autoboot starts booting, U-Boot gives a command prompt. The
124 U-Boot prompt will time out if CONFIG_BOOT_RETRY_TIME is
125 used, otherwise it never times out.
127 config AUTOBOOT_STOP_STR
128 string "Stop autobooting via specific input key / string"
129 depends on AUTOBOOT_KEYED && !AUTOBOOT_ENCRYPTION
131 This option enables stopping (aborting) of the automatic
132 boot feature only by issuing a specific input key or
133 string. If CONFIG_AUTOBOOT_STOP_STR or the environment
134 variable "bootstopkey" is specified and this string is
135 received from console input before autoboot starts booting,
136 U-Boot gives a command prompt. The U-Boot prompt never
137 times out, even if CONFIG_BOOT_RETRY_TIME is used.
139 config AUTOBOOT_KEYED_CTRLC
140 bool "Enable Ctrl-C autoboot interruption"
141 depends on AUTOBOOT_KEYED && !AUTOBOOT_ENCRYPTION
144 This option allows for the boot sequence to be interrupted
145 by ctrl-c, in addition to the "bootdelaykey" and "bootstopkey".
146 Setting this variable provides an escape sequence from the
147 limited "password" strings.
149 config AUTOBOOT_STOP_STR_SHA256
150 string "Stop autobooting via SHA256 encrypted password"
151 depends on AUTOBOOT_KEYED && AUTOBOOT_ENCRYPTION
153 This option adds the feature to only stop the autobooting,
154 and therefore boot into the U-Boot prompt, when the input
155 string / password matches a values that is encypted via
156 a SHA256 hash and saved in the environment.
158 config AUTOBOOT_USE_MENUKEY
159 bool "Allow a specify key to run a menu from the environment"
160 depends on !AUTOBOOT_KEYED
162 If a specific key is pressed to stop autoboot, then the commands in
163 the environment variable 'menucmd' are executed before boot starts.
165 config AUTOBOOT_MENUKEY
166 int "ASCII value of boot key to show a menu"
168 depends on AUTOBOOT_USE_MENUKEY
170 If this key is pressed to stop autoboot, then the commands in the
171 environment variable 'menucmd' will be executed before boot starts.
172 For example, 33 means "!" in ASCII, so pressing ! at boot would take
175 config AUTOBOOT_MENU_SHOW
176 bool "Show a menu on boot"
177 depends on CMD_BOOTMENU
179 This enables the boot menu, controlled by environment variables
180 defined by the board. The menu starts after running the 'preboot'
181 environmnent variable (if enabled) and before handling the boot delay.
182 See README.bootmenu for more details.
204 Print ".config" contents.
206 If this option is enabled, the ".config" file contents are embedded
207 in the U-Boot image and can be printed on the console by the "config"
208 command. This provides information of which options are enabled on
215 Print console devices and information.
220 Print information about available CPUs. This normally shows the
221 number of CPUs, type (e.g. manufacturer, architecture, product or
222 internal name) and clock frequency. Other information may be
223 available depending on the CPU driver.
229 Print GPL license text
245 Run the command stored in the environment "bootcmd", i.e.
246 "bootd" does the same thing as "run bootcmd".
252 Boot an application image from the memory.
257 Boot the Linux zImage
261 depends on ARM64 || RISCV
264 Boot an AArch64 Linux Kernel image from memory.
267 bool "Support booting Linux OS images"
268 depends on CMD_BOOTM || CMD_BOOTZ || CMD_BOOTI
271 Support booting the Linux kernel directly via a command such as bootm
275 bool "Support booting NetBSD (non-EFI) loader images"
279 Support booting NetBSD via the bootm command.
281 config BOOTM_OPENRTOS
282 bool "Support booting OPENRTOS / FreeRTOS images"
285 Support booting OPENRTOS / FreeRTOS via the bootm command.
288 bool "Support booting Enea OSE images"
291 Support booting Enea OSE images via the bootm command.
294 bool "Support booting Plan9 OS images"
298 Support booting Plan9 images via the bootm command.
301 bool "Support booting RTEMS OS images"
305 Support booting RTEMS images via the bootm command.
308 bool "Support booting VxWorks OS images"
312 Support booting VxWorks images via the bootm command.
316 depends on EFI_LOADER
319 Boot an EFI image from memory.
321 config CMD_BOOTEFI_HELLO_COMPILE
322 bool "Compile a standard EFI hello world binary for testing"
323 depends on CMD_BOOTEFI && !CPU_V7M
326 This compiles a standard EFI hello world application with U-Boot so
327 that it can be used with the test/py testing framework. This is useful
328 for testing that EFI is working at a basic level, and for bringing
329 up EFI support on a new architecture.
331 No additional space will be required in the resulting U-Boot binary
332 when this option is enabled.
334 config CMD_BOOTEFI_HELLO
335 bool "Allow booting a standard EFI hello world for testing"
336 depends on CMD_BOOTEFI_HELLO_COMPILE
338 This adds a standard EFI hello world application to U-Boot so that
339 it can be used with the 'bootefi hello' command. This is useful
340 for testing that EFI is working at a basic level, and for bringing
341 up EFI support on a new architecture.
343 source lib/efi_selftest/Kconfig
349 Add an ANSI terminal boot menu command.
354 Android DTB/DTBO image manipulation commands. Read dtb/dtbo files from
355 image into RAM, dump image structure information, etc. Those dtb/dtbo
356 files should be merged in one dtb further, which needs to be passed to
357 the kernel, as part of a boot process.
360 bool "bootelf, bootvx"
363 Boot an ELF/vxWorks image from the memory.
366 bool "Flattened Device Tree utility commands"
370 Do FDT related setup before booting into the Operating System.
376 Start an application at a given address.
382 Run the command in the given environment variable.
388 Print header information for application image.
393 List all images found in flash
399 Extract a part of a multi-image.
402 bool "spl export - Export boot information for Falcon boot"
405 Falcon mode allows booting directly from SPL into an Operating
406 System such as Linux, thus skipping U-Boot proper. See
407 doc/README.falcon for full information about how to use this
410 config CMD_SPL_NAND_OFS
411 hex "Offset of OS args or dtb for Falcon-mode NAND boot"
412 depends on CMD_SPL && (TPL_NAND_SUPPORT || SPL_NAND_SUPPORT)
415 This provides the offset of the command line arguments for Linux
416 when booting from NAND in Falcon mode. See doc/README.falcon
417 for full information about how to use this option (and also see
418 board/gateworks/gw_ventana/README for an example).
420 config CMD_SPL_NOR_OFS
421 hex "Offset of OS args or dtb for Falcon-mode NOR boot"
422 depends on CMD_SPL && SPL_NOR_SUPPORT
425 This provides the offset of the command line arguments or dtb for
426 Linux when booting from NOR in Falcon mode.
428 config CMD_SPL_WRITE_SIZE
429 hex "Size of argument area"
433 This provides the size of the command-line argument area in NAND
434 flash used by Falcon-mode boot. See the documentation until CMD_SPL
438 bool "fitImage update command"
440 Implements the 'fitupd' command, which allows to automatically
441 store software updates present on a TFTP server in NOR Flash
443 config CMD_THOR_DOWNLOAD
444 bool "thor - TIZEN 'thor' download"
447 Implements the 'thor' download protocol. This is a way of
448 downloading a software update over USB from an attached host.
449 There is no documentation about this within the U-Boot source code
450 but you should be able to find something on the interwebs.
453 bool "zboot - x86 boot command"
455 With x86 machines it is common to boot a bzImage file which
456 contains both a kernel and a setup.bin file. The latter includes
457 configuration information from the dark ages which x86 boards still
458 need to pick things out of.
460 Consider using FIT in preference to this since it supports directly
461 booting both 32- and 64-bit kernels, as well as secure boot.
462 Documentation is available in doc/uImage.FIT/x86-fit-boot.txt
466 menu "Environment commands"
469 bool "ask for env variable"
471 Ask for environment variable
489 Edit environment variable.
494 Allow for searching environment variables
500 Save all environment variables into the compiled-in persistent
506 depends on CMD_SAVEENV
508 Erase environment variables from the compiled-in persistent
511 config CMD_ENV_EXISTS
515 Check if a variable is defined in the environment for use in
518 config CMD_ENV_CALLBACK
519 bool "env callbacks - print callbacks and their associated variables"
521 Some environment variable have callbacks defined by
522 U_BOOT_ENV_CALLBACK. These are called when the variable changes.
523 For example changing "baudrate" adjust the serial baud rate. This
524 command lists the currently defined callbacks.
527 bool "env flags -print variables that have non-default flags"
529 Some environment variables have special flags that control their
530 behaviour. For example, serial# can only be written once and cannot
531 be deleted. This command shows the variables that have special
534 config CMD_NVEDIT_EFI
535 bool "env [set|print] -e - set/print UEFI variables"
536 depends on EFI_LOADER
539 UEFI variables are encoded as some form of U-Boot variables.
540 If enabled, we are allowed to set/print UEFI variables using
541 "env" command with "-e" option without knowing details.
543 config CMD_NVEDIT_INFO
544 bool "env info - print or evaluate environment information"
546 Print environment information:
547 - env_valid : is environment valid
548 - env_ready : is environment imported into hash table
549 - env_use_default : is default environment used
551 This command can be optionally used for evaluation in scripts:
552 [-d] : evaluate whether default environment is used
553 [-p] : evaluate whether environment can be persisted
554 The result of multiple evaluations will be combined with AND.
558 menu "Memory commands"
563 Compute binary operations (xor, or, and) of byte arrays of arbitrary
564 size from memory and store the result in memory or the environment.
577 Add -v option to verify data against a crc32 checksum.
580 bool "eeprom - EEPROM subsystem"
582 (deprecated, needs conversion to driver model)
583 Provides commands to read and write EEPROM (Electrically Erasable
584 Programmable Read Only Memory) chips that are connected over an
587 config CMD_EEPROM_LAYOUT
588 bool "Enable layout-aware eeprom commands"
589 depends on CMD_EEPROM
591 (deprecated, needs conversion to driver model)
592 When enabled, additional eeprom sub-commands become available.
594 eeprom print - prints the contents of the eeprom in a human-readable
595 way (eeprom layout fields, and data formatted to be fit for human
598 eeprom update - allows user to update eeprom fields by specifying
599 the field name, and providing the new data in a human readable format
600 (same format as displayed by the eeprom print command).
602 Both commands can either auto detect the layout, or be told which
606 __weak int parse_layout_version(char *str)
607 - override to provide your own layout name parsing
608 __weak void __eeprom_layout_assign(struct eeprom_layout *layout,
610 - override to setup the layout metadata based on the version
611 __weak int eeprom_layout_detect(unsigned char *data)
612 - override to provide your own algorithm for detecting layout
615 - contains various printing and updating functions for common
616 types of eeprom fields. Can be used for defining
619 config EEPROM_LAYOUT_HELP_STRING
620 string "Tells user what layout names are supported"
621 depends on CMD_EEPROM_LAYOUT
622 default "<not defined>"
624 Help printed with the LAYOUT VERSIONS part of the 'eeprom'
630 Infinite write loop on address range
637 Compute MD5 checksum.
642 depends on CMD_MD5SUM
644 Add -v option to verify data against an MD5 checksum.
649 Display memory information.
652 bool "md, mm, nm, mw, cp, cmp, base, loop"
657 mm - memory modify (auto-incrementing address)
658 nm - memory modify (constant address)
659 mw - memory write (fill)
662 base - print or set address offset
663 loop - initialize loop on address range
666 bool "Enable cyclic md/mw commands"
667 depends on CMD_MEMORY
669 Add the "mdc" and "mwc" memory commands. These are cyclic
674 This command will print 4 bytes (10,11,12,13) each 500 ms.
676 => mwc.l 100 12345678 10
677 This command will write 12345678 to address 100 all 10 ms.
682 depends on CMD_MEMORY && (LIB_RAND || LIB_HW_RAND)
684 random - fill memory with random data
689 Simple RAM read/write test.
693 config SYS_ALT_MEMTEST
694 bool "Alternative test"
696 Use a more complete alternative memory test.
703 mdc - memory display cyclic
704 mwc - memory write cyclic
710 Compute SHA1 checksum.
712 config SHA1SUM_VERIFY
714 depends on CMD_SHA1SUM
716 Add -v option to verify data against a SHA1 checksum.
719 bool "strings - display strings in memory"
721 This works similarly to the Unix 'strings' command except that it
722 works with a memory range. String of printable characters found
723 within the range are displayed. The minimum number of characters
724 for a sequence to be considered a string can be provided.
728 menu "Compression commands"
732 default y if CMD_BOOTI
735 Support decompressing an LZMA (Lempel-Ziv-Markov chain algorithm)
740 default y if CMD_BOOTI
742 Uncompress a zip-compressed memory region.
747 Compress a memory region with zlib deflate method.
751 menu "Device access commands"
754 #depends on FLASH_CFI_DRIVER
757 ARM Ltd reference designs flash partition access
760 bool "adc - Access Analog to Digital Converters info and data"
764 Shows ADC device info and permit printing one-shot analog converted
765 data from a named Analog to Digital Converter.
770 depends on PARTITIONS
772 Read/modify/write the fields of Bootloader Control Block, usually
773 stored on the flash "misc" partition with its structure defined in:
774 https://android.googlesource.com/platform/bootable/recovery/+/master/
775 bootloader_message/include/bootloader_message/bootloader_message.h
777 Some real-life use-cases include (but are not limited to):
778 - Determine the "boot reason" (and act accordingly):
779 https://source.android.com/devices/bootloader/boot-reason
780 - Get/pass a list of commands from/to recovery:
781 https://android.googlesource.com/platform/bootable/recovery
782 - Inspect/dump the contents of the BCB fields
785 bool "bind/unbind - Bind or unbind a device to/from a driver"
788 Bind or unbind a device to/from a driver from the command line.
789 This is useful in situations where a device may be handled by several
790 drivers. For example, this can be used to bind a UDC to the usb ether
791 gadget driver from the command line.
794 bool "clk - Show clock frequencies"
797 Shows clock frequences by calling a sock_clk_dump() hook function.
798 This is depreated in favour of using the CLK uclass and accessing
799 clock values from associated drivers. However currently no command
803 bool "demo - Demonstration commands for driver model"
806 Provides a 'demo' command which can be used to play around with
807 driver model. To use this properly you will need to enable one or
808 both of the demo devices (DM_DEMO_SHAPE and DM_DEMO_SIMPLE).
809 Otherwise you will always get an empty list of devices. The demo
810 devices are defined in the sandbox device tree, so the easiest
811 option is to use sandbox and pass the -d point to sandbox's
818 Enables the command "dfu" which is used to have U-Boot create a DFU
819 class device via USB. This command requires that the "dfu_alt_info"
820 environment variable be set and define the alt settings to expose to
824 bool "dm - Access to driver model information"
827 Provides access to driver model data structures and information,
828 such as a list of devices, list of uclasses and the state of each
829 device (e.g. activated). This is not required for operation, but
830 can be useful to see the state of driver model for debugging or
834 bool "fastboot - Android fastboot support"
837 This enables the command "fastboot" which enables the Android
838 fastboot mode for the platform. Fastboot is a protocol for
839 downloading images, flashing and device control used on
840 Android devices. Fastboot requires either the network stack
841 enabled or support for acting as a USB device.
843 See doc/android/fastboot.txt for more information.
846 bool "fdcboot - Boot from floppy device"
848 The 'fdtboot' command allows booting an image from a floppy disk.
851 bool "flinfo, erase, protect"
853 depends on MTD || FLASH_CFI_DRIVER || MTD_NOR_FLASH
856 flinfo - print FLASH memory information
858 protect - enable or disable FLASH write protection
867 config CMD_FPGA_LOADBP
868 bool "fpga loadbp - load partial bitstream (Xilinx only)"
871 Supports loading an FPGA device from a bitstream buffer containing
874 config CMD_FPGA_LOADFS
875 bool "fpga loadfs - load bitstream from FAT filesystem (Xilinx only)"
878 Supports loading an FPGA device from a FAT filesystem.
880 config CMD_FPGA_LOADMK
881 bool "fpga loadmk - load bitstream from image"
884 Supports loading an FPGA device from a image generated by mkimage.
886 config CMD_FPGA_LOADP
887 bool "fpga loadp - load partial bitstream"
890 Supports loading an FPGA device from a bitstream buffer containing
893 config CMD_FPGA_LOAD_SECURE
894 bool "fpga loads - loads secure bitstreams (Xilinx only)"
897 Enables the fpga loads command which is used to load secure
898 (authenticated or encrypted or both) bitstreams on to FPGA.
901 bool "fpgad - dump FPGA registers"
903 (legacy, needs conversion to driver model)
904 Provides a way to dump FPGA registers by calling the board-specific
905 fpga_get_reg() function. This functions similarly to the 'md'
909 bool "fuse - support for the fuse subssystem"
911 (deprecated - needs conversion to driver model)
912 This allows reading, sensing, programming or overriding fuses
913 which control the behaviour of the device. The command uses the
922 bool "GPT (GUID Partition Table) command"
924 select HAVE_BLOCK_DEVICE
925 select PARTITION_UUIDS
928 Enable the 'gpt' command to ready and write GPT style partition
932 bool "GPT Random UUID generation"
935 Enable the generation of partitions with random UUIDs if none
938 config CMD_GPT_RENAME
939 bool "GPT partition renaming commands"
942 Enables the 'gpt' command to interchange names on two GPT
943 partitions via the 'gpt swap' command or to rename single
944 partitions via the 'rename' command.
947 bool "ide - Support for IDE drivers"
950 Provides an 'ide' command which allows accessing the IDE drive,
951 reseting the IDE interface, printing the partition table and
952 geting device info. It also enables the 'diskboot' command which
953 permits booting from an IDE drive.
956 bool "io - Support for performing I/O accesses"
958 Provides an 'iod' command to display I/O space and an 'iow' command
959 to write values to the I/O space. This can be useful for manually
960 checking the state of devices during boot when debugging device
964 bool "iotrace - Support for tracing I/O activity"
966 Provides an 'iotrace' command which supports recording I/O reads and
967 writes in a trace buffer in memory . It also maintains a checksum
968 of the trace records (even if space is exhausted) so that the
969 sequence of I/O accesses can be verified.
971 When debugging drivers it is useful to see what I/O accesses were
972 done and in what order.
974 Even if the individual accesses are of little interest it can be
975 useful to verify that the access pattern is consistent each time
976 an operation is performed. In this case a checksum can be used to
977 characterise the operation of a driver. The checksum can be compared
978 across different runs of the operation to verify that the driver is
981 In particular, when performing major refactoring of the driver, where
982 the access pattern should not change, the checksum provides assurance
983 that the refactoring work has not broken the driver.
985 This works by sneaking into the io.h heder for an architecture and
986 redirecting I/O accesses through iotrace's tracing mechanism.
988 For now no commands are provided to examine the trace buffer. The
989 format is fairly simple, so 'md' is a reasonable substitute.
991 Note: The checksum feature is only useful for I/O regions where the
992 contents do not change outside of software control. Where this is not
993 suitable you can fall back to manually comparing the addresses. It
994 might be useful to enhance tracing to only checksum the accesses and
995 not the data read/written.
1005 bool "w1 - Support for Dallas 1-Wire protocol"
1007 Dallas 1-wire protocol support
1013 Load a binary file over serial line.
1019 Load an S-Record file over serial line
1024 MMC memory mapped support.
1027 bool "Enable support for RPMB in the mmc command"
1030 Enable the commands for reading, writing and programming the
1031 key for the Replay Protection Memory Block partition in eMMC.
1033 config CMD_MMC_SWRITE
1035 depends on CMD_MMC && MMC_WRITE
1038 Enable support for the "mmc swrite" command to write Android sparse
1044 select MTD_PARTITIONS
1046 MTD commands support.
1050 default y if NAND_SUNXI
1051 depends on MTD_RAW_NAND
1056 config CMD_NAND_TRIMFFS
1057 bool "nand write.trimffs"
1058 default y if ARCH_SUNXI
1060 Allows one to skip empty pages when flashing something on a NAND.
1062 config CMD_NAND_LOCK_UNLOCK
1063 bool "nand lock/unlock"
1065 NAND locking support.
1067 config CMD_NAND_TORTURE
1070 NAND torture support.
1079 NVM Express device support
1082 bool "onenand - access to onenand device"
1085 OneNAND is a brand of NAND ('Not AND' gate) flash which provides
1086 various useful features. This command allows reading, writing,
1087 and erasing blocks. It allso provides a way to show and change
1088 bad blocks, and test the device.
1093 Enable the 'osd' command which allows to query information from and
1094 write text data to a on-screen display (OSD) device; a virtual device
1095 associated with a display capable of displaying a text overlay on the
1096 display it's associated with..
1100 select HAVE_BLOCK_DEVICE
1101 select PARTITION_UUIDS
1103 Read and display information about the partition table on
1107 bool "pci - Access PCI devices"
1109 Provide access to PCI (Peripheral Interconnect Bus), a type of bus
1110 used on some devices to allow the CPU to communicate with its
1111 peripherals. Sub-commands allow bus enumeration, displaying and
1112 changing configuration space and a few other features.
1115 bool "pinmux - show pins muxing"
1116 default y if PINCTRL
1118 Parse all available pin-controllers and show pins muxing. This
1119 is useful for debug purpoer to check the pin muxing and to know if
1120 a pin is configured as a GPIO or as an alternate function.
1125 Poweroff/Shutdown the system
1128 bool "read - Read binary data from a partition"
1130 Provides low-level access to the data in a partition.
1132 config CMD_REMOTEPROC
1134 depends on REMOTEPROC
1136 Support for Remote Processor control
1139 bool "sata - Access SATA subsystem"
1142 SATA (Serial Advanced Technology Attachment) is a serial bus
1143 standard for connecting to hard drives and other storage devices.
1144 This command provides information about attached devices and allows
1145 reading, writing and other operations.
1147 SATA replaces PATA (originally just ATA), which stands for Parallel AT
1148 Attachment, where AT refers to an IBM AT (Advanced Technology)
1149 computer released in 1984.
1152 bool "saves - Save a file over serial in S-Record format"
1154 Provides a way to save a binary file using the Motorola S-Record
1155 format over the serial line.
1158 bool "scsi - Access to SCSI devices"
1161 This provides a 'scsi' command which provides access to SCSI (Small
1162 Computer System Interface) devices. The command provides a way to
1163 scan the bus, reset the bus, read and write data and get information
1167 bool "sdram - Print SDRAM configuration information"
1169 Provides information about attached SDRAM. This assumed that the
1170 SDRAM has an EEPROM with information that can be read using the
1171 I2C bus. This is only available on some boards.
1175 depends on DM_SPI_FLASH || SPI_FLASH
1176 default y if DM_SPI_FLASH
1181 bool "sf test - Allow testing of SPI flash"
1184 Provides a way to test that SPI flash is working correctly. The
1185 test is destructive, in that an area of SPI flash must be provided
1186 for the test to use. Performance information is also provided,
1187 measuring the performance of reading, writing and erasing in
1188 Mbps (Million Bits Per Second). This value should approximately
1189 equal the SPI bus speed for a single-bit-wide SPI bus, assuming
1190 everything is working properly.
1193 bool "sspi - Command to access spi device"
1196 SPI utility command.
1198 config DEFAULT_SPI_BUS
1199 int "default spi bus used by sspi command"
1203 config DEFAULT_SPI_MODE
1204 hex "default spi mode used by sspi command (see include/spi.h)"
1209 bool "tsi148 - Command to access tsi148 device"
1211 This provides various sub-commands to initialise and configure the
1212 Turndra tsi148 device. See the command help for full details.
1215 bool "Enable UFS - Universal Flash Subsystem commands"
1218 "This provides commands to initialise and configure universal flash
1222 bool "universe - Command to set up the Turndra Universe controller"
1224 This allows setting up the VMEbus provided by this controller.
1225 See the command help for full details.
1229 select HAVE_BLOCK_DEVICE
1235 select USB_FUNCTION_SDP
1237 Enables the command "sdp" which is used to have U-Boot emulating the
1238 Serial Download Protocol (SDP) via USB.
1242 depends on USB_FUNCTION_ROCKUSB
1244 Rockusb protocol is widely used by Rockchip SoC based devices. It can
1245 read/write info, image to/from devices. This enable rockusb command
1246 support to communication with rockusb device. for more detail about
1247 this command, please read doc/README.rockusb.
1249 config CMD_USB_MASS_STORAGE
1250 bool "UMS usb mass storage"
1251 select USB_FUNCTION_MASS_STORAGE
1253 USB mass storage support
1260 VirtIO block device support
1266 This provides commands to control the watchdog timer devices.
1272 Enable the command "axi" for accessing AXI (Advanced eXtensible
1273 Interface) busses, a on-chip interconnect specification for managing
1274 functional blocks in SoC designs, which is also often used in designs
1275 involving FPGAs (e.g. communication with IP cores in Xilinx FPGAs).
1279 menu "Shell scripting commands"
1285 Echo args to console
1291 Return true/false on integer compare.
1297 Run script from memory
1303 Evaluate boolean and math expressions and store the result in an env
1305 Also supports loading the value at a memory location into a variable.
1306 If CONFIG_REGEX is enabled, setexpr also supports a gsub function.
1310 menu "Android support commands"
1312 config CMD_AB_SELECT
1315 depends on ANDROID_AB
1317 On Android devices with more than one boot slot (multiple copies of
1318 the kernel and system images) this provides a command to select which
1319 slot should be used to boot from and register the boot attempt. This
1320 is used by the new A/B update model where one slot is updated in the
1321 background while running from the other slot.
1328 bool "Network commands"
1338 bootp - boot image via network using BOOTP/TFTP protocol
1342 depends on CMD_BOOTP
1344 Boot image via network using DHCP/TFTP protocol
1346 config BOOTP_BOOTPATH
1347 bool "Request & store 'rootpath' from BOOTP/DHCP server"
1349 depends on CMD_BOOTP
1351 Even though the config is called BOOTP_BOOTPATH, it stores the
1352 path in the variable 'rootpath'.
1355 bool "Request & store 'dnsip' from BOOTP/DHCP server"
1357 depends on CMD_BOOTP
1359 The primary DNS server is stored as 'dnsip'. If two servers are
1360 returned, you must set BOOTP_DNS2 to store that second server IP
1364 bool "Store 'dnsip2' from BOOTP/DHCP server"
1365 depends on BOOTP_DNS
1367 If a DHCP client requests the DNS server IP from a DHCP server,
1368 it is possible that more than one DNS serverip is offered to the
1369 client. If CONFIG_BOOTP_DNS2 is enabled, the secondary DNS
1370 server IP will be stored in the additional environment
1371 variable "dnsip2". The first DNS serverip is always
1372 stored in the variable "dnsip", when BOOTP_DNS is defined.
1374 config BOOTP_GATEWAY
1375 bool "Request & store 'gatewayip' from BOOTP/DHCP server"
1377 depends on CMD_BOOTP
1379 config BOOTP_HOSTNAME
1380 bool "Request & store 'hostname' from BOOTP/DHCP server"
1382 depends on CMD_BOOTP
1384 The name may or may not be qualified with the local domain name.
1386 config BOOTP_PREFER_SERVERIP
1387 bool "serverip variable takes precedent over DHCP server IP."
1388 depends on CMD_BOOTP
1390 By default a BOOTP/DHCP reply will overwrite the 'serverip' variable.
1392 With this option enabled, the 'serverip' variable in the environment
1393 takes precedence over DHCP server IP and will only be set by the DHCP
1394 server if not already set in the environment.
1396 config BOOTP_SUBNETMASK
1397 bool "Request & store 'netmask' from BOOTP/DHCP server"
1399 depends on CMD_BOOTP
1401 config BOOTP_NTPSERVER
1402 bool "Request & store 'ntpserverip' from BOOTP/DHCP server"
1403 depends on CMD_BOOTP
1408 Selecting this will allow capturing all Ethernet packets and store
1409 them in physical memory in a PCAP formated file,
1410 later to be analyzed by PCAP reader application (IE. WireShark).
1413 bool "Send PXE client arch to BOOTP/DHCP server"
1415 depends on CMD_BOOTP && CMD_PXE
1417 Supported for ARM, ARM64, and x86 for now.
1419 config BOOTP_PXE_CLIENTARCH
1421 depends on BOOTP_PXE
1422 default 0x16 if ARM64
1426 config BOOTP_VCI_STRING
1428 depends on CMD_BOOTP
1429 default "U-Boot.armv7" if CPU_V7A || CPU_V7M || CPU_V7R
1430 default "U-Boot.armv8" if ARM64
1431 default "U-Boot.arm" if ARM
1438 tftpboot - boot image via network using TFTP protocol
1442 depends on CMD_TFTPBOOT
1444 TFTP put command, for uploading files to a server
1448 depends on CMD_TFTPBOOT
1450 Act as a TFTP server and boot the first received file
1452 config NET_TFTP_VARS
1453 bool "Control TFTP timeout and count through environment"
1454 depends on CMD_TFTPBOOT
1457 If set, allows controlling the TFTP timeout through the
1458 environment variable tftptimeout, and the TFTP maximum
1459 timeout count through the variable tftptimeoutcountmax.
1460 If unset, timeout and maximum are hard-defined as 1 second
1461 and 10 timouts per TFTP transfer.
1466 Boot image via network using RARP/TFTP protocol
1472 Boot image via network using NFS protocol.
1478 If set, allows 802.3(clause 22) MII Management functions interface access
1479 The management interface specified in Clause 22 provides
1480 a simple, two signal, serial interface to connect a
1481 Station Management entity and a managed PHY for providing access
1482 to management parameters and services.
1483 The interface is referred to as the MII management interface.
1489 If set, allows Enable 802.3(clause 45) MDIO interface registers access
1490 The MDIO interface is orthogonal to the MII interface and extends
1491 it by adding access to more registers through indirect addressing.
1496 Send ICMP ECHO_REQUEST to network host
1501 Perform CDP network configuration
1506 Synchronize RTC via network
1511 Lookup the IP of a hostname
1513 config CMD_LINK_LOCAL
1517 Acquire a network IP address using the link-local protocol
1524 Allow control of L2 Ethernet switch commands. These are supported
1525 by the vsc9953 Ethernet driver at present. Sub-commands allow
1526 operations such as enabling / disabling a port and
1527 viewing/maintaining the filtering database (FDB)
1533 Boot image via network using PXE protocol
1538 Wait for wake-on-lan Magic Packet
1542 menu "Misc commands"
1545 bool "Enable 'bmp' command"
1546 depends on LCD || DM_VIDEO || VIDEO
1548 This provides a way to obtain information about a BMP-format image
1549 and to display it. BMP (which presumably stands for BitMaP) is a
1550 file format defined by Microsoft which supports images of various
1551 depths, formats and compression methods. Headers on the file
1552 determine the formats used. This command can be used by first loading
1553 the image into RAM, then using this command to look at it or display
1556 config CMD_BOOTCOUNT
1558 depends on BOOTCOUNT_LIMIT
1560 Enable the bootcount command, which allows interrogation and
1561 reset of the bootcounter.
1564 bool "Enable board-specific commands"
1566 (deprecated: instead, please define a Kconfig option for each command)
1568 Some boards have board-specific commands which are only enabled
1569 during developemnt and need to be turned off for production. This
1570 option provides a way to control this. The commands that are enabled
1571 vary depending on the board.
1573 config CMD_BKOPS_ENABLE
1574 bool "mmc bkops enable"
1578 Enable command for setting manual background operations handshake
1579 on a eMMC device. The feature is optionally available on eMMC devices
1580 conforming to standard >= 4.41.
1582 config CMD_BLOCK_CACHE
1583 bool "blkcache - control and stats for block cache"
1584 depends on BLOCK_CACHE
1585 default y if BLOCK_CACHE
1587 Enable the blkcache command, which can be used to control the
1588 operation of the cache functions.
1589 This is most useful when fine-tuning the operation of the cache
1590 during development, but also allows the cache to be disabled when
1591 it might hurt performance (e.g. when using the ums command).
1594 bool "icache or dcache"
1596 Enable the "icache" and "dcache" commands
1598 config CMD_CONITRACE
1599 bool "conitrace - trace console input codes"
1601 Enable the 'conitrace' command which displays the codes received
1602 from the console input as hexadecimal numbers.
1605 bool "Enable clear screen command 'cls'"
1606 depends on CFB_CONSOLE || DM_VIDEO || LCD || VIDEO
1609 Enable the 'cls' command which clears the screen contents
1610 on video frame buffer.
1613 bool "efidebug - display/configure UEFI environment"
1614 depends on EFI_LOADER
1615 select EFI_DEVICE_PATH_TO_TEXT
1618 Enable the 'efidebug' command which provides a subset of UEFI
1619 shell utility with simplified functionality. It will be useful
1620 particularly for managing boot parameters as well as examining
1621 various EFI status for debugging.
1623 config CMD_EXCEPTION
1624 bool "exception - raise exception"
1625 depends on ARM || RISCV || X86
1627 Enable the 'exception' command which allows to raise an exception.
1634 Enable the 'led' command which allows for control of LEDs supported
1635 by the board. The LEDs can be listed with 'led list' and controlled
1636 with led on/off/togle/blink. Any LED drivers can be controlled with
1637 this command, e.g. led_gpio.
1644 Enable the 'date' command for getting/setting the time/date in RTC
1650 Run commands and summarize execution time.
1653 bool "gettime - read elapsed time"
1655 Enable the 'gettime' command which reads the elapsed time since
1656 U-Boot started running. This shows the time in seconds and
1657 milliseconds. See also the 'bootstage' command which provides more
1658 flexibility for boot timing.
1660 # TODO: rename to CMD_SLEEP
1665 Delay execution for some time
1668 bool "support for multiprocessor"
1670 This provides an option to brinup
1671 different processors in multiprocessor
1677 Access the system timer.
1683 This provides basic access to the U-Boot's sound support. The main
1684 feature is to play a beep.
1686 sound init - set up sound system
1687 sound play - play a sound
1693 Boot image via local extlinux.conf file
1699 This provides access to the QEMU firmware interface. The main
1700 feature is to allow easy loading of files passed to qemu-system
1701 via -kernel / -initrd
1703 source "cmd/mvebu/Kconfig"
1706 bool "terminal - provides a way to attach a serial terminal"
1708 Provides a 'cu'-like serial terminal command. This can be used to
1709 access other serial ports from the system console. The terminal
1710 is very simple with no special processing of characters. As with
1711 cu, you can press ~. (tilde followed by period) to exit.
1714 bool "uuid, guid - generation of unique IDs"
1717 This enables two commands:
1719 uuid - generate random Universally Unique Identifier
1720 guid - generate Globally Unique Identifier based on random UUID
1722 The two commands are very similar except for the endianness of the
1727 source "cmd/ti/Kconfig"
1729 config CMD_BOOTSTAGE
1730 bool "Enable the 'bootstage' command"
1731 depends on BOOTSTAGE
1733 Add a 'bootstage' command which supports printing a report
1734 and un/stashing of bootstage data.
1736 menu "Power commands"
1738 bool "Enable Driver Model PMIC command"
1741 This is the pmic command, based on a driver model pmic's API.
1742 Command features are unchanged:
1743 - list - list pmic devices
1744 - pmic dev <id> - show or [set] operating pmic device (NEW)
1745 - pmic dump - dump registers
1746 - pmic read address - read byte of register at address
1747 - pmic write address - write byte to register at address
1748 The only one change for this command is 'dev' subcommand.
1750 config CMD_REGULATOR
1751 bool "Enable Driver Model REGULATOR command"
1752 depends on DM_REGULATOR
1754 This command is based on driver model regulator's API.
1755 User interface features:
1756 - list - list regulator devices
1757 - regulator dev <id> - show or [set] operating regulator device
1758 - regulator info - print constraints info
1759 - regulator status - print operating status
1760 - regulator value <val] <-f> - print/[set] voltage value [uV]
1761 - regulator current <val> - print/[set] current value [uA]
1762 - regulator mode <id> - print/[set] operating mode id
1763 - regulator enable - enable the regulator output
1764 - regulator disable - disable the regulator output
1766 The '-f' (force) option can be used for set the value which exceeds
1767 the limits, which are found in device-tree and are kept in regulator's
1768 uclass platdata structure.
1772 menu "Security commands"
1774 bool "Enable the 'aes' command"
1777 This provides a means to encrypt and decrypt data using the AES
1778 (Advanced Encryption Standard). This algorithm uses a symetric key
1779 and is widely used as a streaming cipher. Different key lengths are
1780 supported by the algorithm but this command only supports 128 bits
1784 bool "Enable the 'blob' command"
1786 This is used with the Freescale secure boot mechanism.
1788 Freescale's SEC block has built-in Blob Protocol which provides
1789 a method for protecting user-defined data across system power
1790 cycles. SEC block protects data in a data structure called a Blob,
1791 which provides both confidentiality and integrity protection.
1793 Encapsulating data as a blob
1794 Each time that the Blob Protocol is used to protect data, a
1795 different randomly generated key is used to encrypt the data.
1796 This random key is itself encrypted using a key which is derived
1797 from SoC's non-volatile secret key and a 16 bit Key identifier.
1798 The resulting encrypted key along with encrypted data is called a
1799 blob. The non-volatile secure key is available for use only during
1802 During decapsulation, the reverse process is performed to get back
1806 blob enc - encapsulating data as a cryptgraphic blob
1807 blob dec - decapsulating cryptgraphic blob to get the data
1811 blob enc src dst len km
1813 Encapsulate and create blob of data $len bytes long
1814 at address $src and store the result at address $dst.
1815 $km is the 16 byte key modifier is also required for
1816 generation/use as key for cryptographic operation. Key
1817 modifier should be 16 byte long.
1819 blob dec src dst len km
1821 Decapsulate the blob of data at address $src and
1822 store result of $len byte at addr $dst.
1823 $km is the 16 byte key modifier is also required for
1824 generation/use as key for cryptographic operation. Key
1825 modifier should be 16 byte long.
1828 bool "Support 'hash' command"
1831 This provides a way to hash data in memory using various supported
1832 algorithms (such as SHA1, MD5, CRC32). The computed digest can be
1833 saved to memory or to an environment variable. It is also possible
1834 to verify a hash against data in memory.
1837 bool "Support the 'hvc' command"
1838 depends on ARM_SMCCC
1840 Allows issuing Hypervisor Calls (HVCs). Mostly useful for
1841 development and testing.
1844 bool "Support the 'smc' command"
1845 depends on ARM_SMCCC
1847 Allows issuing Secure Monitor Calls (SMCs). Mostly useful for
1848 development and testing.
1854 Add -v option to verify data against a hash.
1864 bool "Enable the 'tpm' command"
1865 depends on TPM_V1 || TPM_V2
1866 select CMD_TPM_V1 if TPM_V1
1867 select CMD_TPM_V2 if TPM_V2
1869 This provides a means to talk to a TPM from the command line. A wide
1870 range of commands if provided - see 'tpm help' for details. The
1871 command requires a suitable TPM on your board and the correct driver
1877 bool "Enable the 'tpm test' command"
1880 This provides a a series of tests to confirm that the TPMv1.x is
1881 working correctly. The tests cover initialisation, non-volatile RAM,
1882 extend, global lock and checking that timing is within expectations.
1883 The tests pass correctly on Infineon TPMs but may need to be adjusted
1890 menu "Firmware commands"
1892 bool "Enable crosec command"
1896 Enable command-line access to the Chrome OS EC (Embedded
1897 Controller). This provides the 'crosec' command which has
1898 a number of sub-commands for performing EC tasks such as
1899 updating its flash, accessing a small saved context area
1900 and talking to the I2C bus behind the EC (if there is one).
1903 menu "Filesystem commands"
1905 bool "Enable the 'btrsubvol' command"
1908 This enables the 'btrsubvol' command to list subvolumes
1909 of a BTRFS filesystem. There are no special commands for
1910 listing BTRFS directories or loading BTRFS files - this
1911 can be done by the generic 'fs' commands (see CMD_FS_GENERIC)
1912 when BTRFS is enabled (see FS_BTRFS).
1915 bool "Enable the 'cbfs' command"
1918 Define this to enable support for reading from a Coreboot
1919 filesystem. This is a ROM-based filesystem used for accessing files
1920 on systems that use coreboot as the first boot-loader and then load
1921 U-Boot to actually boot the Operating System. Available commands are
1922 cbfsinit, cbfsinfo, cbfsls and cbfsload.
1925 bool "Enable the 'cramfs' command"
1926 depends on FS_CRAMFS
1928 This provides commands for dealing with CRAMFS (Compressed ROM
1929 filesystem). CRAMFS is useful when space is tight since files are
1930 compressed. Two commands are provided:
1932 cramfsls - lists files in a cramfs image
1933 cramfsload - loads a file from a cramfs image
1936 bool "ext2 command support"
1939 Enables EXT2 FS command
1942 bool "ext4 command support"
1945 Enables EXT4 FS command
1947 config CMD_EXT4_WRITE
1949 bool "ext4 write command support"
1952 Enables EXT4 FS write command
1955 bool "FAT command support"
1958 Support for the FAT fs
1960 config CMD_FS_GENERIC
1961 bool "filesystem commands"
1963 Enables filesystem commands (e.g. load, ls) that work for multiple
1967 bool "fsuuid command"
1969 Enables fsuuid command for filesystem UUID.
1972 bool "jffs2 command"
1975 Enables commands to support the JFFS2 (Journalling Flash File System
1976 version 2) filesystem. This enables fsload, ls and fsinfo which
1977 provide the ability to load files, list directories and obtain
1978 filesystem information.
1981 bool "MTD partition support"
1984 MTD partitioning tool support.
1985 It is strongly encouraged to avoid using this command
1986 anymore along with 'sf', 'nand', 'onenand'. One can still
1987 declare the partitions in the mtdparts environment variable
1988 but better use the MTD stack and the 'mtd' command instead.
1990 config CMD_MTDPARTS_SPREAD
1991 bool "Padd partition size to take account of bad blocks"
1992 depends on CMD_MTDPARTS
1994 This enables the 'spread' sub-command of the mtdparts command.
1995 This command will modify the existing mtdparts variable by increasing
1996 the size of the partitions such that 1) each partition's net size is
1997 at least as large as the size specified in the mtdparts variable and
1998 2) each partition starts on a good block.
2000 config CMD_MTDPARTS_SHOW_NET_SIZES
2001 bool "Show net size (w/o bad blocks) of partitions"
2002 depends on CMD_MTDPARTS
2004 Adds two columns to the printed partition table showing the
2005 effective usable size of a partition, if bad blocks are taken
2008 config MTDIDS_DEFAULT
2009 string "Default MTD IDs"
2010 depends on MTD || SPI_FLASH
2012 Defines a default MTD IDs list for use with MTD partitions in the
2013 Linux MTD command line partitions format.
2015 config MTDPARTS_DEFAULT
2016 string "Default MTD partition scheme"
2017 depends on MTD || SPI_FLASH
2019 Defines a default MTD partitioning scheme in the Linux MTD command
2020 line partitions format
2023 bool "reiser - Access to reiserfs filesystems"
2025 This provides two commands which operate on a resierfs filesystem,
2026 commonly used some years ago:
2028 reiserls - list files
2029 reiserload - load a file
2032 bool "yaffs2 - Access of YAFFS2 filesystem"
2036 This provides commands for accessing a YAFFS2 filesystem. Yet
2037 Another Flash Filesystem 2 is a filesystem designed specifically
2038 for NAND flash. It incorporates bad-block management and ensures
2039 that device writes are sequential regardless of filesystem
2043 bool "zfs - Access of ZFS filesystem"
2045 This provides commands to accessing a ZFS filesystem, commonly used
2046 on Solaris systems. Two sub-commands are provided:
2048 zfsls - list files in a directory
2049 zfsload - load a file
2051 See doc/README.zfs for more details.
2055 menu "Debug commands"
2060 The bedbug (emBEDded deBUGger) command provides debugging features
2061 for some PowerPC processors. For details please see the
2062 docuemntation in doc/README.beddbug
2065 bool "diag - Board diagnostics"
2067 This command provides access to board diagnostic tests. These are
2068 called Power-on Self Tests (POST). The command allows listing of
2069 available tests and running either all the tests, or specific tests
2073 bool "irq - Show information about interrupts"
2074 depends on !ARM && !MIPS && !SH
2076 This enables two commands:
2078 interrupts - enable or disable interrupts
2079 irqinfo - print device-specific interrupt information
2082 bool "kgdb - Allow debugging of U-Boot with gdb"
2085 This enables a 'kgdb' command which allows gdb to connect to U-Boot
2086 over a serial link for debugging purposes. This allows
2087 single-stepping, inspecting variables, etc. This is supported only
2088 on PowerPC at present.
2091 bool "log - Generation, control and access to logging"
2094 This provides access to logging features. It allows the output of
2095 log data to be controlled to a limited extent (setting up the default
2096 maximum log level for emitting of records). It also provides access
2097 to a command used for testing the log system.
2100 bool "trace - Support tracing of function calls and timing"
2102 Enables a command to control using of function tracing within
2103 U-Boot. This allows recording of call traces including timing
2104 information. The command can write data to memory for exporting
2105 for analysis (e.g. using bootchart). See doc/README.trace for full
2109 bool "avb - Android Verified Boot 2.0 operations"
2110 depends on AVB_VERIFY
2113 Enables a "avb" command to perform verification of partitions using
2114 Android Verified Boot 2.0 functionality. It includes such subcommands:
2115 avb init - initialize avb2 subsystem
2116 avb read_rb - read rollback index
2117 avb write_rb - write rollback index
2118 avb is_unlocked - check device lock state
2119 avb get_uuid - read and print uuid of a partition
2120 avb read_part - read data from partition
2121 avb read_part_hex - read data from partition and output to stdout
2122 avb write_part - write data to partition
2123 avb verify - run full verification chain
2127 tristate "Enable UBI - Unsorted block images commands"
2130 UBI is a software layer above MTD layer which admits use of LVM-like
2131 logical volumes on top of MTD devices, hides some complexities of
2132 flash chips like wear and bad blocks and provides some other useful
2133 capabilities. Please, consult the MTD web site for more details
2134 (www.linux-mtd.infradead.org). Activate this option if you want
2135 to use U-Boot UBI commands.
2136 It is also strongly encouraged to also enable CONFIG_MTD to get full
2140 tristate "Enable UBIFS - Unsorted block images filesystem commands"
2142 default y if CMD_UBI
2145 UBIFS is a file system for flash devices which works on top of UBI.
projects / oweals / u-boot.git / blob