7 string "Environment file to use"
10 This sets the basename to use to generate the default environment.
11 This a text file as described in doc/usage/environment.rst
13 The file must be in the board directory and have a .env extension, so
14 the resulting filename is typically
15 board/<vendor>/<board>/<CONFIG_ENV_SOURCE_FILE>.env
17 If the file is not present, an error is produced.
19 If this CONFIG is empty, U-Boot uses CONFIG SYS_BOARD as a default, if
20 the file board/<vendor>/<board>/<SYS_BOARD>.env exists. Otherwise the
21 environment is assumed to come from the ad-hoc
22 CFG_EXTRA_ENV_SETTINGS #define
25 def_bool y if CMD_SAVEENV
28 bool "Enable overwriting environment"
30 Use this to permit overriding of certain environmental variables
31 like Ethernet and Serial
33 config OVERWRITE_ETHADDR_ONCE
34 bool "Enable overwriting ethaddr environment variables once"
35 depends on !ENV_OVERWRITE
37 Enable this to allow for the ethaddr environment variables to be
38 overwritten one time per boot, only. This allows for a default
39 to be installed in the environment, which can be changed exactly ONCE
42 config ENV_MIN_ENTRIES
43 int "Minimum number of entries in the environment hashtable"
46 Minimum number of entries in the hash table that is used internally
47 to store the environment settings.
49 config ENV_MAX_ENTRIES
50 int "Maximumm number of entries in the environment hashtable"
53 Maximum number of entries in the hash table that is used internally
54 to store the environment settings. The default setting is supposed to
55 be generous and should work in most cases. This setting can be used
56 to tune behaviour; see lib/hashtable.c for details.
59 def_bool y if !ENV_IS_IN_EEPROM && !ENV_IS_IN_EXT4 && \
60 !ENV_IS_IN_FAT && !ENV_IS_IN_FLASH && \
61 !ENV_IS_IN_MMC && !ENV_IS_IN_NAND && \
62 !ENV_IS_IN_NVRAM && !ENV_IS_IN_ONENAND && \
63 !ENV_IS_IN_REMOTE && !ENV_IS_IN_SPI_FLASH && \
68 bool "Environment is not stored"
70 Define this if you don't care whether or not an environment is stored
71 on a storage medium. In this case the environment will still exist
72 while U-Boot is running, but once U-Boot exits it may not be
73 stored. If no other ENV_IS_IN_ is defined, U-Boot will always start
74 up with the default environment.
76 config ENV_IS_IN_EEPROM
77 bool "Environment in EEPROM"
78 depends on !CHAIN_OF_TRUST
80 Use this if you have an EEPROM or similar serial access
81 device and a driver for it.
86 These two #defines specify the offset and size of the
87 environment area within the total memory of your EEPROM.
89 Note that we consider the length of the address field to
90 still be one byte because the extra address bits are hidden
93 EEPROM which holds the environment, is reached over
94 a pca9547 i2c mux with address 0x70, channel 3.
97 bool "Environment is in a FAT filesystem"
98 depends on !CHAIN_OF_TRUST
99 default y if ARCH_BCM283X
100 default y if ARCH_SUNXI && MMC
101 default y if MMC_OMAP_HS && TI_COMMON_CMD_OPTIONS
105 Define this if you want to use the FAT file system for the environment.
107 config ENV_IS_IN_EXT4
108 bool "Environment is in a EXT4 filesystem"
109 depends on !CHAIN_OF_TRUST
113 Define this if you want to use the EXT4 file system for the environment.
115 config ENV_IS_IN_FLASH
116 bool "Environment in flash memory"
117 depends on !CHAIN_OF_TRUST
118 default y if ARCH_CINTEGRATOR
119 default y if ARCH_INTEGRATOR_CP
120 default y if M548x || M547x || M5282
121 default y if MCF532x || MCF52x2
122 default y if MPC86xx || MPC83xx
123 default y if ARCH_MPC8548
124 default y if SH && !CPU_SH4
126 Define this if you have a flash device which you want to use for the
129 a) The environment occupies one whole flash sector, which is
130 "embedded" in the text segment with the U-Boot code. This
131 happens usually with "bottom boot sector" or "top boot
132 sector" type flash chips, which have several smaller
133 sectors at the start or the end. For instance, such a
134 layout can have sector sizes of 8, 2x4, 16, Nx32 kB. In
135 such a case you would place the environment in one of the
136 4 kB sectors - with U-Boot code before and after it. With
137 "top boot sector" type flash chips, you would put the
138 environment in one of the last sectors, leaving a gap
139 between U-Boot and the environment.
143 Offset of environment data (variable area) to the
144 beginning of flash memory; for instance, with bottom boot
145 type flash chips the second sector can be used: the offset
146 for this sector is given here.
148 CONFIG_ENV_OFFSET is used relative to CFG_SYS_FLASH_BASE.
152 This is just another way to specify the start address of
153 the flash sector containing the environment (instead of
156 CONFIG_ENV_SECT_SIZE:
158 Size of the sector containing the environment.
161 b) Sometimes flash chips have few, equal sized, BIG sectors.
162 In such a case you don't want to spend a whole sector for
167 If you use this in combination with CONFIG_ENV_IS_IN_FLASH
168 and CONFIG_ENV_SECT_SIZE, you can specify to use only a part
169 of this flash sector for the environment. This saves
170 memory for the RAM copy of the environment.
172 It may also save flash memory if you decide to use this
173 when your environment is "embedded" within U-Boot code,
174 since then the remainder of the flash sector could be used
175 for U-Boot code. It should be pointed out that this is
176 STRONGLY DISCOURAGED from a robustness point of view:
177 updating the environment in flash makes it always
178 necessary to erase the WHOLE sector. If something goes
179 wrong before the contents has been restored from a copy in
180 RAM, your target system will be dead.
182 CONFIG_ENV_ADDR_REDUND
184 These settings describe a second storage area used to hold
185 a redundant copy of the environment data, so that there is
186 a valid backup copy in case there is a power failure during
187 a "saveenv" operation.
189 BE CAREFUL! Any changes to the flash layout, and some changes to the
190 source code will make it necessary to adapt <board>/u-boot.lds*
194 bool "Environment in an MMC device"
195 depends on !CHAIN_OF_TRUST
197 default y if ARCH_EXYNOS4
198 default y if MX6SX || MX7D
199 default y if TEGRA30 || TEGRA124
200 default y if TEGRA_ARMV8_COMMON
202 Define this if you have an MMC device which you want to use for the
205 CONFIG_SYS_MMC_ENV_DEV:
207 Specifies which MMC device the environment is stored in.
209 CONFIG_SYS_MMC_ENV_PART (optional):
211 Specifies which MMC partition the environment is stored in. If not
212 set, defaults to partition 0, the user area. Common values might be
213 1 (first MMC boot partition), 2 (second MMC boot partition).
218 These two #defines specify the offset and size of the environment
219 area within the specified MMC device.
221 If offset is positive (the usual case), it is treated as relative to
222 the start of the MMC partition. If offset is negative, it is treated
223 as relative to the end of the MMC partition. This can be useful if
224 your board may be fitted with different MMC devices, which have
225 different sizes for the MMC partitions, and you always want the
226 environment placed at the very end of the partition, to leave the
227 maximum possible space before it, to store other data.
229 These two values are in units of bytes, but must be aligned to an
232 CONFIG_ENV_OFFSET_REDUND (optional):
234 Specifies a second storage area, of CONFIG_ENV_SIZE size, used to
235 hold a redundant copy of the environment data. This provides a
236 valid backup copy in case the other copy is corrupted, e.g. due
237 to a power failure during a "saveenv" operation.
239 This value may also be positive or negative; this is handled in the
240 same way as CONFIG_ENV_OFFSET.
242 In case CONFIG_SYS_MMC_ENV_PART is 1 (i.e. environment in eMMC boot
243 partition) then setting CONFIG_ENV_OFFSET_REDUND to the same value
244 as CONFIG_ENV_OFFSET makes use of the second eMMC boot partition for
245 the redundant environment copy.
247 This value is also in units of bytes, but must also be aligned to
248 an MMC sector boundary.
250 CONFIG_ENV_MMC_USE_DT (optional):
252 These define forces the configuration by the config node in device
253 tree with partition name: "u-boot,mmc-env-partition" or with
254 offset: "u-boot,mmc-env-offset", "u-boot,mmc-env-offset-redundant".
255 CONFIG_ENV_OFFSET and CONFIG_ENV_OFFSET_REDUND are not used.
257 config ENV_IS_IN_NAND
258 bool "Environment in a NAND device"
259 depends on !CHAIN_OF_TRUST
261 Define this if you have a NAND device which you want to use for the
267 These two #defines specify the offset and size of the environment
268 area within the first NAND device. CONFIG_ENV_OFFSET must be
269 aligned to an erase block boundary.
271 - CONFIG_ENV_OFFSET_REDUND (optional):
273 This setting describes a second storage area of CONFIG_ENV_SIZE
274 size used to hold a redundant copy of the environment data, so
275 that there is a valid backup copy in case there is a power failure
276 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be
277 aligned to an erase block boundary.
279 - CONFIG_ENV_OFFSET_OOB (optional):
281 Enables support for dynamically retrieving the offset of the
282 environment from block zero's out-of-band data. The
283 "nand env.oob" command can be used to record this offset.
284 Currently, CONFIG_ENV_OFFSET_REDUND is not supported when
285 using CONFIG_ENV_OFFSET_OOB.
288 hex "Length of the region in which the environment can be written"
289 depends on ENV_IS_IN_NAND
290 range ENV_SIZE 0x7fffffff
293 This should be a multiple of the NAND device's block size.
294 Specifying a range with more erase blocks than are needed to hold
295 CONFIG_ENV_SIZE allows bad blocks within the range to be avoided.
297 config ENV_IS_IN_NVRAM
298 bool "Environment in a non-volatile RAM"
299 depends on !CHAIN_OF_TRUST
301 Define this if you have some non-volatile memory device
302 (NVRAM, battery buffered SRAM) which you want to use for the
308 These two #defines are used to determine the memory area you
309 want to use for environment. It is assumed that this memory
310 can just be read and written to, without any special
313 config ENV_IS_IN_ONENAND
314 bool "Environment is in OneNAND"
315 depends on !CHAIN_OF_TRUST && CMD_ONENAND
317 Define this if you want to put your local device's environment in
323 These two #defines are used to determine the device range you
324 want to use for environment. It is assumed that this memory
325 can just be read and written to, without any special
328 config ENV_IS_IN_REMOTE
329 bool "Environment is in remote memory space"
330 depends on !CHAIN_OF_TRUST
332 Define this if you have a remote memory space which you
333 want to use for the local device's environment.
338 These two #defines specify the address and size of the
339 environment area within the remote memory space. The
340 local device can get the environment from remote memory
341 space by SRIO or PCIE links.
343 config ENV_IS_IN_SPI_FLASH
344 bool "Environment is in SPI flash"
345 depends on !CHAIN_OF_TRUST && (SPI_FLASH || DM_SPI_FLASH)
346 default y if ARMADA_XP
347 default y if INTEL_BAYTRAIL
348 default y if INTEL_BRASWELL
349 default y if INTEL_BROADWELL
350 default y if NORTHBRIDGE_INTEL_IVYBRIDGE
351 default y if INTEL_QUARK
352 default y if INTEL_QUEENSBAY
353 default y if ARCH_SUNXI
355 Define this if you have a SPI Flash memory device which you
356 want to use for the environment.
361 These two #defines specify the offset and size of the
362 environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
363 aligned to an erase sector boundary.
365 - CONFIG_ENV_SECT_SIZE:
367 Define the SPI flash's sector size.
369 - CONFIG_ENV_OFFSET_REDUND (optional):
371 This setting describes a second storage area of CONFIG_ENV_SIZE
372 size used to hold a redundant copy of the environment data, so
373 that there is a valid backup copy in case there is a power failure
374 during a "saveenv" operation. CONFIG_ENV_OFFSET_REDUND must be
375 aligned to an erase sector boundary.
377 config ENV_SECT_SIZE_AUTO
378 bool "Use automatically detected sector size"
379 depends on ENV_IS_IN_SPI_FLASH
381 Some boards exist in multiple variants, with different
382 flashes having different sector sizes. In such cases, you
383 can select this option to make U-Boot use the actual sector
384 size when figuring out how much to erase, which can thus be
385 more efficient on the flashes with smaller erase size. Since
386 the environment must always be aligned on a sector boundary,
387 CONFIG_ENV_OFFSET must be aligned to the largest of the
388 different sector sizes, and CONFIG_ENV_SECT_SIZE should be
392 int "Value of SPI flash bus for environment"
393 depends on ENV_IS_IN_SPI_FLASH
394 default SF_DEFAULT_BUS
396 Value the SPI bus and chip select for environment.
399 int "Value of SPI flash chip select for environment"
400 depends on ENV_IS_IN_SPI_FLASH
401 default SF_DEFAULT_CS
403 Value of the SPI chip select for environment.
405 config ENV_SPI_MAX_HZ
406 int "Value of SPI flash max frequency for environment"
407 depends on ENV_IS_IN_SPI_FLASH
408 default SF_DEFAULT_SPEED
410 Value of the SPI max work clock for environment.
413 hex "Value of SPI flash work mode for environment"
414 depends on ENV_IS_IN_SPI_FLASH
415 default SF_DEFAULT_MODE
417 Value of the SPI work mode for environment.
418 See include/spi.h for value.
421 bool "Access Environment in SPI flashes before relocation"
422 depends on ENV_IS_IN_SPI_FLASH
424 Enable this if you want to use Environment in SPI flash
425 before relocation. Call env_init() and than you can use
426 env_get_f() for accessing Environment variables.
429 bool "Environment in a UBI volume"
430 depends on !CHAIN_OF_TRUST
434 Define this if you have an UBI volume that you want to use for the
435 environment. This has the benefit of wear-leveling the environment
436 accesses, which is important on NAND.
438 - CONFIG_ENV_UBI_PART:
440 Define this to a string that is the mtd partition containing the UBI.
442 - CONFIG_ENV_UBI_VOLUME:
444 Define this to the name of the volume that you want to store the
447 - CONFIG_ENV_UBI_VOLUME_REDUND:
449 Define this to the name of another volume to store a second copy of
450 the environment in. This will enable redundant environments in UBI.
451 It is assumed that both volumes are in the same MTD partition.
453 config SYS_REDUNDAND_ENVIRONMENT
454 bool "Enable redundant environment support"
456 Normally, the environemt is stored in a single location. By
457 selecting this option, you can then define where to hold a redundant
458 copy of the environment data, so that there is a valid backup copy in
459 case there is a power failure during a "saveenv" operation.
460 Also this config changes the binary environment structure handling
461 which is used by env import/export commands which are independent of
462 storing variables to redundant location on a non volatile device.
464 config ENV_FAT_INTERFACE
465 string "Name of the block device for the environment"
466 depends on ENV_IS_IN_FAT
469 Define this to a string that is the name of the block device.
471 config ENV_FAT_DEVICE_AND_PART
472 string "Device and partition for where to store the environemt in FAT"
473 depends on ENV_IS_IN_FAT
474 default "0:1" if TI_COMMON_CMD_OPTIONS
475 default "0:auto" if ARCH_ZYNQ || ARCH_ZYNQMP || ARCH_VERSAL || ARCH_VERSAL_NET
476 default ":auto" if ARCH_SUNXI
477 default "0" if ARCH_AT91
479 Define this to a string to specify the partition of the device. It can
482 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
483 - "D:P": device D partition P. Error occurs if device D has no
486 - "D" or "D:": device D partition 1 if device D has partition
487 table, or the whole device D if has no partition
489 - "D:auto": first partition in device D with bootable flag set.
490 If none, first valid partition in device D. If no
491 partition table then means device D.
493 If ENV_FAT_INTERFACE is set to "mmc" then device 'D' can be omitted,
494 leaving the string starting with a colon, and the boot device will
498 string "Name of the FAT file to use for the environment"
499 depends on ENV_IS_IN_FAT
502 It's a string of the FAT file name. This file use to store the
505 config ENV_FAT_FILE_REDUND
506 string "Name of the FAT file to use for the environment"
507 depends on ENV_IS_IN_FAT && SYS_REDUNDAND_ENVIRONMENT
508 default "uboot-redund.env"
510 It's a string of the FAT file name. This file use to store the
511 redundant environment.
513 config ENV_EXT4_INTERFACE
514 string "Name of the block device for the environment"
515 depends on ENV_IS_IN_EXT4
517 Define this to a string that is the name of the block device.
519 config ENV_EXT4_DEVICE_AND_PART
520 string "Device and partition for where to store the environemt in EXT4"
521 depends on ENV_IS_IN_EXT4
523 Define this to a string to specify the partition of the device. It can
526 "D:P", "D:0", "D", "D:" or "D:auto" (D, P are integers. And P >= 1)
527 - "D:P": device D partition P. Error occurs if device D has no
530 - "D" or "D:": device D partition 1 if device D has partition
531 table, or the whole device D if has no partition
533 - "D:auto": first partition in device D with bootable flag set.
534 If none, first valid partition in device D. If no
535 partition table then means device D.
537 If ENV_EXT4_INTERFACE is set to "mmc" then device 'D' can be omitted,
538 leaving the string starting with a colon, and the boot device will
542 string "Name of the EXT4 file to use for the environment"
543 depends on ENV_IS_IN_EXT4
546 It's a string of the EXT4 file name. This file use to store the
547 environment (explicit path to the file)
550 hex "Environment address"
551 depends on ENV_IS_IN_FLASH || ENV_IS_IN_NVRAM || ENV_IS_IN_ONENAND || \
552 ENV_IS_IN_REMOTE || ENV_IS_IN_SPI_FLASH
553 default 0x0 if ENV_IS_IN_SPI_FLASH
555 Offset from the start of the device (or partition)
557 config ENV_ADDR_REDUND
558 hex "Redundant environment address"
559 depends on ENV_IS_IN_FLASH && SYS_REDUNDAND_ENVIRONMENT
561 Offset from the start of the device (or partition) of the redundant
562 environment location.
565 hex "Environment offset"
566 depends on ENV_IS_IN_EEPROM || ENV_IS_IN_MMC || ENV_IS_IN_NAND || \
568 default 0x3f8000 if ARCH_ROCKCHIP && ENV_IS_IN_MMC
569 default 0x140000 if ARCH_ROCKCHIP && ENV_IS_IN_SPI_FLASH
570 default 0xF0000 if ARCH_SUNXI
571 default 0xE0000 if ARCH_ZYNQ
572 default 0x1E00000 if ARCH_ZYNQMP
573 default 0x7F40000 if ARCH_VERSAL || ARCH_VERSAL_NET
575 default 0x140000 if ARCH_AT91
576 default 0x260000 if ARCH_OMAP2PLUS
577 default 0x1080000 if MICROBLAZE && ENV_IS_IN_SPI_FLASH
579 Offset from the start of the device (or partition).
581 This offset may be interpreted differently depending on the chosen
582 ENV_IS_IN_* options. For example, for ENV_IS_IN_MMC=y, this offset may
583 be negative to indicate an offset backwards from the end of the
584 partition. See the relevant help messages for more details.
586 config ENV_OFFSET_REDUND
587 hex "Redundant environment offset"
588 depends on (ENV_IS_IN_EEPROM || ENV_IS_IN_MMC || ENV_IS_IN_NAND || \
589 ENV_IS_IN_SPI_FLASH) && SYS_REDUNDAND_ENVIRONMENT
590 default 0x10C0000 if MICROBLAZE
593 Offset from the start of the device (or partition) of the redundant
594 environment location.
596 This offset may be interpreted differently depending on the chosen
597 ENV_IS_IN_* options. For example, for ENV_IS_IN_MMC=y, this offset may
598 be negative to indicate an offset backwards from the end of the
599 partition. See the relevant help messages for more details.
602 hex "Environment Size"
603 default 0x40000 if ENV_IS_IN_SPI_FLASH && ARCH_ZYNQMP
604 default 0x20000 if ARCH_ZYNQ || ARCH_OMAP2PLUS || ARCH_AT91
605 default 0x10000 if ARCH_SUNXI
606 default 0x8000 if ARCH_ROCKCHIP && ENV_IS_IN_MMC
607 default 0x2000 if ARCH_ROCKCHIP && ENV_IS_IN_SPI_FLASH
608 default 0x8000 if ARCH_ZYNQMP || ARCH_VERSAL || ARCH_VERSAL_NET
609 default 0x4000 if ARC
612 Size of the environment storage area
615 hex "Environment Sector-Size"
616 depends on ENV_IS_IN_FLASH || ENV_IS_IN_SPI_FLASH
617 default 0x2000 if ARCH_ROCKCHIP
618 default 0x40000 if ARCH_ZYNQMP || ARCH_VERSAL || ARCH_VERSAL_NET
619 default 0x20000 if ARCH_ZYNQ || ARCH_OMAP2PLUS || ARCH_AT91
620 default 0x20000 if MICROBLAZE && ENV_IS_IN_SPI_FLASH
621 default 0x10000 if ARCH_SUNXI && ENV_IS_IN_SPI_FLASH
623 Size of the sector containing the environment.
626 string "UBI partition name"
627 depends on ENV_IS_IN_UBI
629 MTD partition containing the UBI device
631 config ENV_UBI_VOLUME
632 string "UBI volume name"
633 depends on ENV_IS_IN_UBI
635 Name of the volume that you want to store the environment in.
637 config ENV_UBI_VOLUME_REDUND
638 string "UBI redundant volume name"
639 depends on ENV_IS_IN_UBI && SYS_REDUNDAND_ENVIRONMENT
641 Name of the redundant volume that you want to store the environment in.
643 config ENV_UBI_VID_OFFSET
644 int "ubi environment VID offset"
645 depends on ENV_IS_IN_UBI
648 UBI VID offset for environment. If 0, no custom VID offset is used.
650 config SYS_RELOC_GD_ENV_ADDR
651 bool "Relocate gd->env_addr"
653 Relocate the early env_addr pointer so we know it is not inside
654 the binary. Some systems need this and for the rest, it doesn't hurt.
656 config SYS_MMC_ENV_DEV
657 int "mmc device number"
658 depends on ENV_IS_IN_MMC || ENV_IS_IN_FAT || \
659 CMD_MVEBU_BUBT || FMAN_ENET || QE || PHY_CORTINA
662 MMC device number on the platform where the environment is stored.
664 config SYS_MMC_ENV_PART
665 int "mmc partition number"
666 depends on ENV_IS_IN_MMC || ENV_IS_IN_FAT
669 MMC hardware partition device number on the platform where the
670 environment is stored. Note that this is not related to any software
671 defined partition table but instead if we are in the user area, which is
672 partition 0 or the first boot partition, which is 1 or some other defined
675 config USE_ENV_MMC_PARTITION
676 bool "use the mmc environment partition name"
677 depends on ENV_IS_IN_MMC
679 config ENV_MMC_PARTITION
680 string "mmc environment partition name"
681 depends on USE_ENV_MMC_PARTITION
683 MMC partition name used to save environment variables.
684 If this variable is unset, u-boot will try to get the env partition name
685 from the device-tree's /config node.
687 config ENV_MMC_USE_DT
688 bool "Read partition name and offset in DT"
689 depends on ENV_IS_IN_MMC && OF_CONTROL
691 Only use the device tree to get the environment location in MMC
692 device, with partition name or with offset.
693 The 2 defines CONFIG_ENV_OFFSET, CONFIG_ENV_OFFSET_REDUND
694 are not used as fallback.
696 config USE_DEFAULT_ENV_FILE
697 bool "Create default environment from file"
699 Normally, the default environment is automatically generated
700 based on the settings of various CONFIG_* options, as well
701 as the CFG_EXTRA_ENV_SETTINGS. By selecting this option,
702 you can instead define the entire default environment in an
705 config DEFAULT_ENV_FILE
706 string "Path to default environment file"
707 depends on USE_DEFAULT_ENV_FILE
709 The path containing the default environment. The format is
710 the same as accepted by the mkenvimage tool: lines
711 containing key=value pairs, blank lines and lines beginning
714 config ENV_VARS_UBOOT_RUNTIME_CONFIG
715 bool "Add run-time information to the environment"
717 Enable this in order to add variables describing certain
718 run-time determined information about the hardware to the
719 environment. These will be named board_name, board_rev.
721 config DELAY_ENVIRONMENT
722 bool "Delay environment loading"
723 depends on !OF_CONTROL
725 Enable this to inhibit loading the environment during board
726 initialization. This can address the security risk of untrusted data
727 being used during boot. Normally the environment is loaded when the
728 board is initialised so that it is available to U-Boot. This inhibits
729 that so that the environment is not available until explicitly loaded
730 later by U-Boot code. With CONFIG_OF_CONTROL this is instead
731 controlled by the value of /config/load-environment.
733 config ENV_IMPORT_FDT
734 bool "Amend environment by FDT properties"
735 depends on OF_CONTROL
737 If selected, after the environment has been loaded from its
738 persistent location, the "env_fdt_path" variable is looked
739 up and used as a path to a node in the control DTB. The
740 property/value pairs in that node is then used to update the
741 run-time environment. This can be useful to use the same
742 U-Boot binary with different board variants.
745 string "Default value for env_fdt_path variable"
746 depends on ENV_IMPORT_FDT
747 default "/config/environment"
749 The initial value of the env_fdt_path variable.
752 bool "Always append the environment with new data"
754 If defined, the environment hash table is only ever appended with new
755 data, but the existing hash table can never be dropped and reloaded
756 with newly imported data. This may be used in combination with static
757 flags to e.g. to protect variables which must not be modified.
759 config ENV_WRITEABLE_LIST
760 bool "Permit write access only to listed variables"
763 If defined, only environment variables which explicitly set the 'w'
764 writeable flag can be written and modified at runtime. No variables
765 can be otherwise created, written or imported into the environment.
767 config ENV_ACCESS_IGNORE_FORCE
768 bool "Block forced environment operations"
770 If defined, don't allow the -f switch to env set override variable
774 config SPL_ENV_IS_NOWHERE
775 bool "SPL Environment is not stored"
776 default y if ENV_IS_NOWHERE
778 Similar to ENV_IS_NOWHERE, used for SPL environment.
780 config SPL_ENV_IS_IN_MMC
781 bool "SPL Environment in an MMC device"
782 depends on !SPL_ENV_IS_NOWHERE
783 depends on ENV_IS_IN_MMC
786 Similar to ENV_IS_IN_MMC, used for SPL environment.
788 config SPL_ENV_IS_IN_FAT
789 bool "SPL Environment is in a FAT filesystem"
790 depends on !SPL_ENV_IS_NOWHERE
791 depends on ENV_IS_IN_FAT
794 Similar to ENV_IS_IN_FAT, used for SPL environment.
796 config SPL_ENV_IS_IN_EXT4
797 bool "SPL Environment is in a EXT4 filesystem"
798 depends on !SPL_ENV_IS_NOWHERE
799 depends on ENV_IS_IN_EXT4
802 Similar to ENV_IS_IN_EXT4, used for SPL environment.
804 config SPL_ENV_IS_IN_NAND
805 bool "SPL Environment in a NAND device"
806 depends on !SPL_ENV_IS_NOWHERE
807 depends on ENV_IS_IN_NAND
810 Similar to ENV_IS_IN_NAND, used for SPL environment.
812 config SPL_ENV_IS_IN_SPI_FLASH
813 bool "SPL Environment is in SPI flash"
814 depends on !SPL_ENV_IS_NOWHERE
815 depends on ENV_IS_IN_SPI_FLASH
818 Similar to ENV_IS_IN_SPI_FLASH, used for SPL environment.
820 config SPL_ENV_IS_IN_FLASH
821 bool "SPL Environment in flash memory"
822 depends on !SPL_ENV_IS_NOWHERE
823 depends on ENV_IS_IN_FLASH
826 Similar to ENV_IS_IN_FLASH, used for SPL environment.
832 config TPL_ENV_IS_NOWHERE
833 bool "TPL Environment is not stored"
834 default y if ENV_IS_NOWHERE
836 Similar to ENV_IS_NOWHERE, used for TPL environment.
838 config TPL_ENV_IS_IN_MMC
839 bool "TPL Environment in an MMC device"
840 depends on !TPL_ENV_IS_NOWHERE
841 depends on ENV_IS_IN_MMC
844 Similar to ENV_IS_IN_MMC, used for TPL environment.
846 config TPL_ENV_IS_IN_FAT
847 bool "TPL Environment is in a FAT filesystem"
848 depends on !TPL_ENV_IS_NOWHERE
849 depends on ENV_IS_IN_FAT
852 Similar to ENV_IS_IN_FAT, used for TPL environment.
854 config TPL_ENV_IS_IN_EXT4
855 bool "TPL Environment is in a EXT4 filesystem"
856 depends on !TPL_ENV_IS_NOWHERE
857 depends on ENV_IS_IN_EXT4
860 Similar to ENV_IS_IN_EXT4, used for TPL environment.
862 config TPL_ENV_IS_IN_NAND
863 bool "TPL Environment in a NAND device"
864 depends on !TPL_ENV_IS_NOWHERE
865 depends on ENV_IS_IN_NAND
868 Similar to ENV_IS_IN_NAND, used for TPL environment.
870 config TPL_ENV_IS_IN_SPI_FLASH
871 bool "TPL Environment is in SPI flash"
872 depends on !TPL_ENV_IS_NOWHERE
873 depends on ENV_IS_IN_SPI_FLASH
876 Similar to ENV_IS_IN_SPI_FLASH, used for TPL environment.
878 config TPL_ENV_IS_IN_FLASH
879 bool "TPL Environment in flash memory"
880 depends on !TPL_ENV_IS_NOWHERE
881 depends on ENV_IS_IN_FLASH
884 Similar to ENV_IS_IN_FLASH, used for TPL environment.
890 config VPL_ENV_IS_NOWHERE
891 bool "VPL Environment is not stored"
892 default y if ENV_IS_NOWHERE
894 Similar to ENV_IS_NOWHERE, used for VPL environment.
896 endif # VPL_ENV_SUPPORT
899 bool "Add a 'bootfile' environment variable"
901 The "bootfile" variable is used in some cases to allow for
902 controlling what file U-Boot will attempt to load and boot. To set
903 this, enable this option and set the value in the next question.
906 string "'bootfile' environment variable value"
907 depends on USE_BOOTFILE
909 The value to set the "bootfile" variable to.
912 bool "Add an 'ethprime' environment variable"
914 The "ethprime" variable is used in some cases to control which
915 network interface is used first.
918 string "'ethprime' environment variable value"
919 depends on USE_ETHPRIME
921 The value to set the "ethprime" variable to.
924 bool "Set a default 'hostname' value in the environment"
928 string "Value of the default 'hostname' value in the environment"
929 depends on USE_HOSTNAME
933 config VERSION_VARIABLE
934 bool "Add a 'ver' environment variable with the U-Boot version"
936 If this variable is defined, an environment variable
937 named "ver" is created by U-Boot showing the U-Boot
938 version as printed by the "version" command.
939 Any change to this variable will be reverted at the