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Simon Glassb45b1632020-09-10 20:21:13 -06001menu "Boot options"
2
3menu "Boot images"
4
5config ANDROID_BOOT_IMAGE
6 bool "Enable support for Android Boot Images"
7 default y if FASTBOOT
8 help
9 This enables support for booting images which use the Android
10 image format header.
11
12config FIT
13 bool "Support Flattened Image Tree"
Alexandru Gagniuc650b7862021-09-02 19:54:21 -050014 select HASH
Simon Glassb45b1632020-09-10 20:21:13 -060015 select MD5
16 select SHA1
Alexandru Gagniuc8d310ef2021-09-02 19:54:17 -050017 imply SHA256
Simon Glassb45b1632020-09-10 20:21:13 -060018 help
19 This option allows you to boot the new uImage structure,
20 Flattened Image Tree. FIT is formally a FDT, which can include
21 images of various types (kernel, FDT blob, ramdisk, etc.)
22 in a single blob. To boot this new uImage structure,
23 pass the address of the blob to the "bootm" command.
24 FIT is very flexible, supporting compression, multiple images,
25 multiple configurations, verification through hashing and also
26 verified boot (secure boot using RSA).
27
Simon Glass65831d92021-12-18 11:27:50 -070028config TIMESTAMP
29 bool "Show image date and time when displaying image information"
30 default y if CMD_DATE
31 help
32 When CONFIG_TIMESTAMP is selected, the timestamp (date and time) of
33 an image is printed by image commands like bootm or iminfo. This
34 is shown as 'Timestamp: xxx' and 'Created: xxx'. If this option is
35 enabled, then U-Boot requires FITs to have a timestamp. If a FIT is
36 loaded that does not, the message 'Wrong FIT format: no timestamp'
37 is shown.
38
Simon Glassb45b1632020-09-10 20:21:13 -060039if FIT
40
41config FIT_EXTERNAL_OFFSET
42 hex "FIT external data offset"
43 default 0x0
44 help
45 This specifies a data offset in fit image.
46 The offset is from data payload offset to the beginning of
47 fit image header. When specifies a offset, specific data
48 could be put in the hole between data payload and fit image
49 header, such as CSF data on i.MX platform.
50
Simon Glass244705b2021-02-15 17:08:10 -070051config FIT_FULL_CHECK
52 bool "Do a full check of the FIT before using it"
53 default y
54 help
55 Enable this do a full check of the FIT to make sure it is valid. This
56 helps to protect against carefully crafted FITs which take advantage
57 of bugs or omissions in the code. This includes a bad structure,
58 multiple root nodes and the like.
59
Simon Glassb45b1632020-09-10 20:21:13 -060060config FIT_SIGNATURE
61 bool "Enable signature verification of FIT uImages"
62 depends on DM
63 select HASH
Alexandru Gagniuc1f2e2312021-07-29 11:47:18 -050064 imply RSA
65 imply RSA_VERIFY
Simon Glassb45b1632020-09-10 20:21:13 -060066 select IMAGE_SIGN_INFO
Simon Glass244705b2021-02-15 17:08:10 -070067 select FIT_FULL_CHECK
Simon Glassb45b1632020-09-10 20:21:13 -060068 help
69 This option enables signature verification of FIT uImages,
70 using a hash signed and verified using RSA. If
71 CONFIG_SHA_PROG_HW_ACCEL is defined, i.e support for progressive
72 hashing is available using hardware, then the RSA library will use
73 it. See doc/uImage.FIT/signature.txt for more details.
74
75 WARNING: When relying on signed FIT images with a required signature
76 check the legacy image format is disabled by default, so that
77 unsigned images cannot be loaded. If a board needs the legacy image
78 format support in this case, enable it using
79 CONFIG_LEGACY_IMAGE_FORMAT.
80
81config FIT_SIGNATURE_MAX_SIZE
82 hex "Max size of signed FIT structures"
83 depends on FIT_SIGNATURE
84 default 0x10000000
85 help
86 This option sets a max size in bytes for verified FIT uImages.
87 A sane value of 256MB protects corrupted DTB structures from overlapping
88 device memory. Assure this size does not extend past expected storage
89 space.
90
Simon Glass66b00c82021-07-14 17:05:31 -050091config FIT_RSASSA_PSS
Simon Glassb45b1632020-09-10 20:21:13 -060092 bool "Support rsassa-pss signature scheme of FIT image contents"
93 depends on FIT_SIGNATURE
Simon Glassb45b1632020-09-10 20:21:13 -060094 help
95 Enable this to support the pss padding algorithm as described
96 in the rfc8017 (https://tools.ietf.org/html/rfc8017).
97
98config FIT_CIPHER
99 bool "Enable ciphering data in a FIT uImages"
100 depends on DM
101 select AES
102 help
103 Enable the feature of data ciphering/unciphering in the tool mkimage
104 and in the u-boot support of the FIT image.
105
106config FIT_VERBOSE
107 bool "Show verbose messages when FIT images fail"
108 help
109 Generally a system will have valid FIT images so debug messages
110 are a waste of code space. If you are debugging your images then
111 you can enable this option to get more verbose information about
112 failures.
113
114config FIT_BEST_MATCH
115 bool "Select the best match for the kernel device tree"
116 help
117 When no configuration is explicitly selected, default to the
118 one whose fdt's compatibility field best matches that of
119 U-Boot itself. A match is considered "best" if it matches the
120 most specific compatibility entry of U-Boot's fdt's root node.
121 The order of entries in the configuration's fdt is ignored.
122
123config FIT_IMAGE_POST_PROCESS
124 bool "Enable post-processing of FIT artifacts after loading by U-Boot"
Siew Chin Lim2492d592021-03-01 20:04:11 +0800125 depends on TI_SECURE_DEVICE || SOCFPGA_SECURE_VAB_AUTH
Simon Glassb45b1632020-09-10 20:21:13 -0600126 help
127 Allows doing any sort of manipulation to blobs after they got extracted
128 from FIT images like stripping off headers or modifying the size of the
129 blob, verification, authentication, decryption etc. in a platform or
130 board specific way. In order to use this feature a platform or board-
131 specific implementation of board_fit_image_post_process() must be
132 provided. Also, anything done during this post-processing step would
133 need to be comprehended in how the images were prepared before being
134 injected into the FIT creation (i.e. the blobs would have been pre-
135 processed before being added to the FIT image).
136
Ravik Hasija11dac412021-01-27 14:01:48 -0800137config FIT_PRINT
138 bool "Support FIT printing"
139 default y
140 help
141 Support printing the content of the fitImage in a verbose manner.
142
Simon Glassb45b1632020-09-10 20:21:13 -0600143if SPL
144
145config SPL_FIT
146 bool "Support Flattened Image Tree within SPL"
147 depends on SPL
Alexandru Gagniuc650b7862021-09-02 19:54:21 -0500148 select SPL_HASH
Simon Glassb45b1632020-09-10 20:21:13 -0600149 select SPL_OF_LIBFDT
150
151config SPL_FIT_PRINT
152 bool "Support FIT printing within SPL"
153 depends on SPL_FIT
154 help
155 Support printing the content of the fitImage in a verbose manner in SPL.
156
Simon Glass244705b2021-02-15 17:08:10 -0700157config SPL_FIT_FULL_CHECK
158 bool "Do a full check of the FIT before using it"
159 help
160 Enable this do a full check of the FIT to make sure it is valid. This
161 helps to protect against carefully crafted FITs which take advantage
162 of bugs or omissions in the code. This includes a bad structure,
163 multiple root nodes and the like.
164
165
Simon Glassb45b1632020-09-10 20:21:13 -0600166config SPL_FIT_SIGNATURE
167 bool "Enable signature verification of FIT firmware within SPL"
168 depends on SPL_DM
Klaus Heinrich Kiwiae5073f2021-02-09 15:41:54 -0300169 depends on SPL_LOAD_FIT || SPL_LOAD_FIT_FULL
Klaus Heinrich Kiwic9796e62021-02-09 15:41:53 -0300170 select FIT_SIGNATURE
Simon Glassb45b1632020-09-10 20:21:13 -0600171 select SPL_FIT
Simon Glassa8437ce2021-07-10 21:14:25 -0600172 select SPL_CRYPTO
Alexandru Gagniuc97464ff2021-09-02 19:54:19 -0500173 select SPL_HASH
Alexandru Gagniuc1f2e2312021-07-29 11:47:18 -0500174 imply SPL_RSA
175 imply SPL_RSA_VERIFY
Simon Glassb45b1632020-09-10 20:21:13 -0600176 select SPL_IMAGE_SIGN_INFO
Simon Glass244705b2021-02-15 17:08:10 -0700177 select SPL_FIT_FULL_CHECK
Simon Glassb45b1632020-09-10 20:21:13 -0600178
Simon Glassc0cabbc2021-09-25 19:43:39 -0600179config SPL_FIT_SIGNATURE_MAX_SIZE
180 hex "Max size of signed FIT structures in SPL"
181 depends on SPL_FIT_SIGNATURE
182 default 0x10000000
183 help
184 This option sets a max size in bytes for verified FIT uImages.
185 A sane value of 256MB protects corrupted DTB structures from overlapping
186 device memory. Assure this size does not extend past expected storage
187 space.
188
Philippe Reynes47f3eb22021-10-15 11:35:03 +0200189config SPL_FIT_RSASSA_PSS
190 bool "Support rsassa-pss signature scheme of FIT image contents in SPL"
191 depends on SPL_FIT_SIGNATURE
192 help
193 Enable this to support the pss padding algorithm as described
194 in the rfc8017 (https://tools.ietf.org/html/rfc8017) in SPL.
195
Simon Glassb45b1632020-09-10 20:21:13 -0600196config SPL_LOAD_FIT
197 bool "Enable SPL loading U-Boot as a FIT (basic fitImage features)"
198 select SPL_FIT
199 help
200 Normally with the SPL framework a legacy image is generated as part
201 of the build. This contains U-Boot along with information as to
202 where it should be loaded. This option instead enables generation
203 of a FIT (Flat Image Tree) which provides more flexibility. In
204 particular it can handle selecting from multiple device tree
205 and passing the correct one to U-Boot.
206
Alexandru Gagniuc064c9c22021-03-29 12:05:15 -0500207 This path has the following limitations:
208
Bin Meng91cdcb92021-05-10 20:23:29 +0800209 1. "loadables" images, other than FDTs, which do not have a "load"
Alexandru Gagniuc064c9c22021-03-29 12:05:15 -0500210 property will not be loaded. This limitation also applies to FPGA
211 images with the correct "compatible" string.
212 2. For FPGA images, only the "compatible" = "u-boot,fpga-legacy"
213 loading method is supported.
214 3. FDTs are only loaded for images with an "os" property of "u-boot".
215 "linux" images are also supported with Falcon boot mode.
216
Simon Glassb45b1632020-09-10 20:21:13 -0600217config SPL_LOAD_FIT_ADDRESS
218 hex "load address of fit image"
219 depends on SPL_LOAD_FIT
220 default 0x0
221 help
222 Specify the load address of the fit image that will be loaded
223 by SPL.
224
225config SPL_LOAD_FIT_APPLY_OVERLAY
226 bool "Enable SPL applying DT overlays from FIT"
227 depends on SPL_LOAD_FIT
228 select OF_LIBFDT_OVERLAY
229 help
230 The device tree is loaded from the FIT image. Allow the SPL is to
231 also load device-tree overlays from the FIT image an apply them
232 over the device tree.
233
234config SPL_LOAD_FIT_APPLY_OVERLAY_BUF_SZ
235 depends on SPL_LOAD_FIT_APPLY_OVERLAY
236 default 0x10000
237 hex "size of temporary buffer used to load the overlays"
238 help
239 The size of the area where the overlays will be loaded and
240 uncompress. Must be at least as large as biggest overlay
241 (uncompressed)
242
243config SPL_LOAD_FIT_FULL
244 bool "Enable SPL loading U-Boot as a FIT (full fitImage features)"
245 select SPL_FIT
246 help
247 Normally with the SPL framework a legacy image is generated as part
248 of the build. This contains U-Boot along with information as to
249 where it should be loaded. This option instead enables generation
250 of a FIT (Flat Image Tree) which provides more flexibility. In
251 particular it can handle selecting from multiple device tree
252 and passing the correct one to U-Boot.
253
254config SPL_FIT_IMAGE_POST_PROCESS
255 bool "Enable post-processing of FIT artifacts after loading by the SPL"
256 depends on SPL_LOAD_FIT
257 help
258 Allows doing any sort of manipulation to blobs after they got extracted
259 from the U-Boot FIT image like stripping off headers or modifying the
260 size of the blob, verification, authentication, decryption etc. in a
261 platform or board specific way. In order to use this feature a platform
262 or board-specific implementation of board_fit_image_post_process() must
263 be provided. Also, anything done during this post-processing step would
264 need to be comprehended in how the images were prepared before being
265 injected into the FIT creation (i.e. the blobs would have been pre-
266 processed before being added to the FIT image).
267
268config SPL_FIT_SOURCE
269 string ".its source file for U-Boot FIT image"
270 depends on SPL_FIT
271 help
272 Specifies a (platform specific) FIT source file to generate the
273 U-Boot FIT image. This could specify further image to load and/or
274 execute.
275
276config USE_SPL_FIT_GENERATOR
277 bool "Use a script to generate the .its script"
Bin Meng442d4462021-05-10 20:23:41 +0800278 default y if SPL_FIT && (!ARCH_SUNXI && !RISCV)
Simon Glassb45b1632020-09-10 20:21:13 -0600279
280config SPL_FIT_GENERATOR
281 string ".its file generator script for U-Boot FIT image"
282 depends on USE_SPL_FIT_GENERATOR
283 default "arch/arm/mach-rockchip/make_fit_atf.py" if SPL_LOAD_FIT && ARCH_ROCKCHIP
284 default "arch/arm/mach-zynqmp/mkimage_fit_atf.sh" if SPL_LOAD_FIT && ARCH_ZYNQMP
Simon Glassb45b1632020-09-10 20:21:13 -0600285 help
286 Specifies a (platform specific) script file to generate the FIT
287 source file used to build the U-Boot FIT image file. This gets
288 passed a list of supported device tree file stub names to
289 include in the generated image.
290
291endif # SPL
292
293endif # FIT
294
295config LEGACY_IMAGE_FORMAT
296 bool "Enable support for the legacy image format"
297 default y if !FIT_SIGNATURE
298 help
299 This option enables the legacy image format. It is enabled by
300 default for backward compatibility, unless FIT_SIGNATURE is
301 set where it is disabled so that unsigned images cannot be
302 loaded. If a board needs the legacy image format support in this
303 case, enable it here.
304
Simon Glassf11d6132020-09-10 20:21:19 -0600305config SUPPORT_RAW_INITRD
306 bool "Enable raw initrd images"
307 help
308 Note, defining the SUPPORT_RAW_INITRD allows user to supply
309 kernel with raw initrd images. The syntax is slightly different, the
310 address of the initrd must be augmented by it's size, in the following
311 format: "<initrd address>:<initrd size>".
312
Simon Glassb45b1632020-09-10 20:21:13 -0600313config OF_BOARD_SETUP
314 bool "Set up board-specific details in device tree before boot"
315 depends on OF_LIBFDT
316 help
317 This causes U-Boot to call ft_board_setup() before booting into
318 the Operating System. This function can set up various
319 board-specific information in the device tree for use by the OS.
320 The device tree is then passed to the OS.
321
322config OF_SYSTEM_SETUP
323 bool "Set up system-specific details in device tree before boot"
324 depends on OF_LIBFDT
325 help
326 This causes U-Boot to call ft_system_setup() before booting into
327 the Operating System. This function can set up various
328 system-specific information in the device tree for use by the OS.
329 The device tree is then passed to the OS.
330
331config OF_STDOUT_VIA_ALIAS
332 bool "Update the device-tree stdout alias from U-Boot"
333 depends on OF_LIBFDT
334 help
335 This uses U-Boot's serial alias from the aliases node to update
336 the device tree passed to the OS. The "linux,stdout-path" property
337 in the chosen node is set to point to the correct serial node.
338 This option currently references CONFIG_CONS_INDEX, which is
339 incorrect when used with device tree as this option does not
340 exist / should not be used.
341
342config SYS_EXTRA_OPTIONS
343 string "Extra Options (DEPRECATED)"
344 help
345 The old configuration infrastructure (= mkconfig + boards.cfg)
346 provided the extra options field. If you have something like
347 "HAS_BAR,BAZ=64", the optional options
348 #define CONFIG_HAS
349 #define CONFIG_BAZ 64
350 will be defined in include/config.h.
351 This option was prepared for the smooth migration from the old
352 configuration to Kconfig. Since this option will be removed sometime,
353 new boards should not use this option.
354
355config HAVE_SYS_TEXT_BASE
356 bool
357 depends on !NIOS2 && !XTENSA
358 depends on !EFI_APP
359 default y
360
361config SYS_TEXT_BASE
362 depends on HAVE_SYS_TEXT_BASE
Tom Rini63471d52021-07-09 10:39:21 -0400363 default 0x0 if POSITION_INDEPENDENT
Simon Glassb45b1632020-09-10 20:21:13 -0600364 default 0x80800000 if ARCH_OMAP2PLUS || ARCH_K3
365 default 0x4a000000 if ARCH_SUNXI && !MACH_SUN9I && !MACH_SUN8I_V3S
366 default 0x2a000000 if ARCH_SUNXI && MACH_SUN9I
367 default 0x42e00000 if ARCH_SUNXI && MACH_SUN8I_V3S
368 hex "Text Base"
369 help
370 The address in memory that U-Boot will be running from, initially.
371
Tom Rini8c70baa2021-12-14 13:36:40 -0500372config DYNAMIC_SYS_CLK_FREQ
373 bool "Determine CPU clock frequency at run-time"
374 help
375 Implement a get_board_sys_clk function that will determine the CPU
376 clock frequency at run time, rather than define it statically.
377
Simon Glassb45b1632020-09-10 20:21:13 -0600378config SYS_CLK_FREQ
Tom Rini8c70baa2021-12-14 13:36:40 -0500379 depends on !DYNAMIC_SYS_CLK_FREQ
Simon Glassb45b1632020-09-10 20:21:13 -0600380 int "CPU clock frequency"
Tom Rini8c70baa2021-12-14 13:36:40 -0500381 default 125000000 if ARCH_LS1012A
382 default 100000000 if ARCH_P2020 || ARCH_T1024 || ARCH_T1042 || \
383 ARCH_LS1021A || FSL_LSCH2 || FSL_LSCH3
384 default 66666666 if ARCH_P1010 || ARCH_P1020 || ARCH_T4240
385 default 66660000 if ARCH_T2080
386 default 33333333 if RCAR_GEN3
387 default 24000000 if ARCH_EXYNOS
388 default 20000000 if RCAR_GEN2
389 default 0
Simon Glassb45b1632020-09-10 20:21:13 -0600390 help
Tom Rini8c70baa2021-12-14 13:36:40 -0500391 A static value for the CPU frequency. Note that if not required
392 for a given SoC, this can be left at 0.
Simon Glassb45b1632020-09-10 20:21:13 -0600393
394config ARCH_FIXUP_FDT_MEMORY
395 bool "Enable arch_fixup_memory_banks() call"
396 default y
397 help
398 Enable FDT memory map syncup before OS boot. This feature can be
399 used for booting OS with different memory setup where the part of
400 the memory location should be used for different purpose.
401
Simon Glassd81f07f2020-11-04 09:57:35 -0700402config CHROMEOS
403 bool "Support booting Chrome OS"
404 help
405 Chrome OS requires U-Boot to set up a table indicating the boot mode
406 (e.g. Developer mode) and a few other things. Enable this if you are
407 booting on a Chromebook to avoid getting an error about an invalid
408 firmware ID.
409
410config CHROMEOS_VBOOT
411 bool "Support Chrome OS verified boot"
412 help
413 This is intended to enable the full Chrome OS verified boot support
414 in U-Boot. It is not actually implemented in the U-Boot source code
415 at present, so this option is always set to 'n'. It allows
416 distinguishing between booting Chrome OS in a basic way (developer
417 mode) and a full boot.
418
Tom Rini9ff815a2021-08-24 23:11:49 -0400419config RAMBOOT_PBL
420 bool "Freescale PBL(pre-boot loader) image format support"
421 help
422 Some SoCs use PBL to load RCW and/or pre-initialization instructions.
423 For more details refer to doc/README.pblimage
424
425config SYS_FSL_PBL_PBI
426 string "PBI(pre-boot instructions) commands for the PBL image"
427 depends on RAMBOOT_PBL
428 help
429 PBI commands can be used to configure SoC before it starts the execution.
430 Please refer doc/README.pblimage for more details.
431
432config SYS_FSL_PBL_RCW
433 string "Aadditional RCW (Power on reset configuration) for the PBL image"
434 depends on RAMBOOT_PBL
435 help
436 Enables addition of RCW (Power on reset configuration) in built image.
437 Please refer doc/README.pblimage for more details.
438
Simon Glassb45b1632020-09-10 20:21:13 -0600439endmenu # Boot images
440
Simon Glassd02ddcf2020-09-10 20:21:14 -0600441menu "Boot timing"
442
443config BOOTSTAGE
444 bool "Boot timing and reporting"
445 help
446 Enable recording of boot time while booting. To use it, insert
447 calls to bootstage_mark() with a suitable BOOTSTAGE_ID from
448 bootstage.h. Only a single entry is recorded for each ID. You can
449 give the entry a name with bootstage_mark_name(). You can also
450 record elapsed time in a particular stage using bootstage_start()
451 before starting and bootstage_accum() when finished. Bootstage will
452 add up all the accumulated time and report it.
453
454 Normally, IDs are defined in bootstage.h but a small number of
455 additional 'user' IDs can be used by passing BOOTSTAGE_ID_ALLOC
456 as the ID.
457
458 Calls to show_boot_progress() will also result in log entries but
459 these will not have names.
460
461config SPL_BOOTSTAGE
462 bool "Boot timing and reported in SPL"
463 depends on BOOTSTAGE
464 help
465 Enable recording of boot time in SPL. To make this visible to U-Boot
466 proper, enable BOOTSTAGE_STASH as well. This will stash the timing
467 information when SPL finishes and load it when U-Boot proper starts
468 up.
469
470config TPL_BOOTSTAGE
471 bool "Boot timing and reported in TPL"
472 depends on BOOTSTAGE
473 help
474 Enable recording of boot time in SPL. To make this visible to U-Boot
475 proper, enable BOOTSTAGE_STASH as well. This will stash the timing
476 information when TPL finishes and load it when U-Boot proper starts
477 up.
478
479config BOOTSTAGE_REPORT
480 bool "Display a detailed boot timing report before booting the OS"
481 depends on BOOTSTAGE
482 help
483 Enable output of a boot time report just before the OS is booted.
484 This shows how long it took U-Boot to go through each stage of the
485 boot process. The report looks something like this:
486
487 Timer summary in microseconds:
488 Mark Elapsed Stage
489 0 0 reset
490 3,575,678 3,575,678 board_init_f start
491 3,575,695 17 arch_cpu_init A9
492 3,575,777 82 arch_cpu_init done
493 3,659,598 83,821 board_init_r start
494 3,910,375 250,777 main_loop
495 29,916,167 26,005,792 bootm_start
496 30,361,327 445,160 start_kernel
497
498config BOOTSTAGE_RECORD_COUNT
499 int "Number of boot stage records to store"
Simon Glass051ddfb2021-02-03 06:00:49 -0700500 depends on BOOTSTAGE
Simon Glassd02ddcf2020-09-10 20:21:14 -0600501 default 30
502 help
503 This is the size of the bootstage record list and is the maximum
504 number of bootstage records that can be recorded.
505
506config SPL_BOOTSTAGE_RECORD_COUNT
507 int "Number of boot stage records to store for SPL"
Simon Glass051ddfb2021-02-03 06:00:49 -0700508 depends on SPL_BOOTSTAGE
Simon Glassd02ddcf2020-09-10 20:21:14 -0600509 default 5
510 help
511 This is the size of the bootstage record list and is the maximum
512 number of bootstage records that can be recorded.
513
514config TPL_BOOTSTAGE_RECORD_COUNT
515 int "Number of boot stage records to store for TPL"
Simon Glass051ddfb2021-02-03 06:00:49 -0700516 depends on TPL_BOOTSTAGE
Simon Glassd02ddcf2020-09-10 20:21:14 -0600517 default 5
518 help
519 This is the size of the bootstage record list and is the maximum
520 number of bootstage records that can be recorded.
521
522config BOOTSTAGE_FDT
523 bool "Store boot timing information in the OS device tree"
524 depends on BOOTSTAGE
525 help
526 Stash the bootstage information in the FDT. A root 'bootstage'
527 node is created with each bootstage id as a child. Each child
528 has a 'name' property and either 'mark' containing the
529 mark time in microseconds, or 'accum' containing the
530 accumulated time for that bootstage id in microseconds.
531 For example:
532
533 bootstage {
534 154 {
535 name = "board_init_f";
536 mark = <3575678>;
537 };
538 170 {
539 name = "lcd";
540 accum = <33482>;
541 };
542 };
543
544 Code in the Linux kernel can find this in /proc/devicetree.
545
546config BOOTSTAGE_STASH
547 bool "Stash the boot timing information in memory before booting OS"
548 depends on BOOTSTAGE
549 help
550 Some OSes do not support device tree. Bootstage can instead write
551 the boot timing information in a binary format at a given address.
552 This happens through a call to bootstage_stash(), typically in
553 the CPU's cleanup_before_linux() function. You can use the
554 'bootstage stash' and 'bootstage unstash' commands to do this on
555 the command line.
556
557config BOOTSTAGE_STASH_ADDR
558 hex "Address to stash boot timing information"
559 default 0
560 help
561 Provide an address which will not be overwritten by the OS when it
562 starts, so that it can read this information when ready.
563
564config BOOTSTAGE_STASH_SIZE
565 hex "Size of boot timing stash region"
566 default 0x1000
567 help
568 This should be large enough to hold the bootstage stash. A value of
569 4096 (4KiB) is normally plenty.
570
571config SHOW_BOOT_PROGRESS
572 bool "Show boot progress in a board-specific manner"
573 help
574 Defining this option allows to add some board-specific code (calling
575 a user-provided function show_boot_progress(int) that enables you to
576 show the system's boot progress on some display (for example, some
577 LEDs) on your board. At the moment, the following checkpoints are
578 implemented:
579
580 Legacy uImage format:
581
582 Arg Where When
583 1 common/cmd_bootm.c before attempting to boot an image
584 -1 common/cmd_bootm.c Image header has bad magic number
585 2 common/cmd_bootm.c Image header has correct magic number
586 -2 common/cmd_bootm.c Image header has bad checksum
587 3 common/cmd_bootm.c Image header has correct checksum
588 -3 common/cmd_bootm.c Image data has bad checksum
589 4 common/cmd_bootm.c Image data has correct checksum
590 -4 common/cmd_bootm.c Image is for unsupported architecture
591 5 common/cmd_bootm.c Architecture check OK
592 -5 common/cmd_bootm.c Wrong Image Type (not kernel, multi)
593 6 common/cmd_bootm.c Image Type check OK
594 -6 common/cmd_bootm.c gunzip uncompression error
595 -7 common/cmd_bootm.c Unimplemented compression type
596 7 common/cmd_bootm.c Uncompression OK
597 8 common/cmd_bootm.c No uncompress/copy overwrite error
598 -9 common/cmd_bootm.c Unsupported OS (not Linux, BSD, VxWorks, QNX)
599
600 9 common/image.c Start initial ramdisk verification
601 -10 common/image.c Ramdisk header has bad magic number
602 -11 common/image.c Ramdisk header has bad checksum
603 10 common/image.c Ramdisk header is OK
604 -12 common/image.c Ramdisk data has bad checksum
605 11 common/image.c Ramdisk data has correct checksum
606 12 common/image.c Ramdisk verification complete, start loading
607 -13 common/image.c Wrong Image Type (not PPC Linux ramdisk)
608 13 common/image.c Start multifile image verification
609 14 common/image.c No initial ramdisk, no multifile, continue.
610
611 15 arch/<arch>/lib/bootm.c All preparation done, transferring control to OS
612
613 -30 arch/powerpc/lib/board.c Fatal error, hang the system
614 -31 post/post.c POST test failed, detected by post_output_backlog()
615 -32 post/post.c POST test failed, detected by post_run_single()
616
617 34 common/cmd_doc.c before loading a Image from a DOC device
618 -35 common/cmd_doc.c Bad usage of "doc" command
619 35 common/cmd_doc.c correct usage of "doc" command
620 -36 common/cmd_doc.c No boot device
621 36 common/cmd_doc.c correct boot device
622 -37 common/cmd_doc.c Unknown Chip ID on boot device
623 37 common/cmd_doc.c correct chip ID found, device available
624 -38 common/cmd_doc.c Read Error on boot device
625 38 common/cmd_doc.c reading Image header from DOC device OK
626 -39 common/cmd_doc.c Image header has bad magic number
627 39 common/cmd_doc.c Image header has correct magic number
628 -40 common/cmd_doc.c Error reading Image from DOC device
629 40 common/cmd_doc.c Image header has correct magic number
630 41 common/cmd_ide.c before loading a Image from a IDE device
631 -42 common/cmd_ide.c Bad usage of "ide" command
632 42 common/cmd_ide.c correct usage of "ide" command
633 -43 common/cmd_ide.c No boot device
634 43 common/cmd_ide.c boot device found
635 -44 common/cmd_ide.c Device not available
636 44 common/cmd_ide.c Device available
637 -45 common/cmd_ide.c wrong partition selected
638 45 common/cmd_ide.c partition selected
639 -46 common/cmd_ide.c Unknown partition table
640 46 common/cmd_ide.c valid partition table found
641 -47 common/cmd_ide.c Invalid partition type
642 47 common/cmd_ide.c correct partition type
643 -48 common/cmd_ide.c Error reading Image Header on boot device
644 48 common/cmd_ide.c reading Image Header from IDE device OK
645 -49 common/cmd_ide.c Image header has bad magic number
646 49 common/cmd_ide.c Image header has correct magic number
647 -50 common/cmd_ide.c Image header has bad checksum
648 50 common/cmd_ide.c Image header has correct checksum
649 -51 common/cmd_ide.c Error reading Image from IDE device
650 51 common/cmd_ide.c reading Image from IDE device OK
651 52 common/cmd_nand.c before loading a Image from a NAND device
652 -53 common/cmd_nand.c Bad usage of "nand" command
653 53 common/cmd_nand.c correct usage of "nand" command
654 -54 common/cmd_nand.c No boot device
655 54 common/cmd_nand.c boot device found
656 -55 common/cmd_nand.c Unknown Chip ID on boot device
657 55 common/cmd_nand.c correct chip ID found, device available
658 -56 common/cmd_nand.c Error reading Image Header on boot device
659 56 common/cmd_nand.c reading Image Header from NAND device OK
660 -57 common/cmd_nand.c Image header has bad magic number
661 57 common/cmd_nand.c Image header has correct magic number
662 -58 common/cmd_nand.c Error reading Image from NAND device
663 58 common/cmd_nand.c reading Image from NAND device OK
664
665 -60 common/env_common.c Environment has a bad CRC, using default
666
667 64 net/eth.c starting with Ethernet configuration.
668 -64 net/eth.c no Ethernet found.
669 65 net/eth.c Ethernet found.
670
671 -80 common/cmd_net.c usage wrong
672 80 common/cmd_net.c before calling net_loop()
673 -81 common/cmd_net.c some error in net_loop() occurred
674 81 common/cmd_net.c net_loop() back without error
675 -82 common/cmd_net.c size == 0 (File with size 0 loaded)
676 82 common/cmd_net.c trying automatic boot
677 83 common/cmd_net.c running "source" command
678 -83 common/cmd_net.c some error in automatic boot or "source" command
679 84 common/cmd_net.c end without errors
680
681 FIT uImage format:
682
683 Arg Where When
684 100 common/cmd_bootm.c Kernel FIT Image has correct format
685 -100 common/cmd_bootm.c Kernel FIT Image has incorrect format
686 101 common/cmd_bootm.c No Kernel subimage unit name, using configuration
687 -101 common/cmd_bootm.c Can't get configuration for kernel subimage
688 102 common/cmd_bootm.c Kernel unit name specified
689 -103 common/cmd_bootm.c Can't get kernel subimage node offset
690 103 common/cmd_bootm.c Found configuration node
691 104 common/cmd_bootm.c Got kernel subimage node offset
692 -104 common/cmd_bootm.c Kernel subimage hash verification failed
693 105 common/cmd_bootm.c Kernel subimage hash verification OK
694 -105 common/cmd_bootm.c Kernel subimage is for unsupported architecture
695 106 common/cmd_bootm.c Architecture check OK
696 -106 common/cmd_bootm.c Kernel subimage has wrong type
697 107 common/cmd_bootm.c Kernel subimage type OK
698 -107 common/cmd_bootm.c Can't get kernel subimage data/size
699 108 common/cmd_bootm.c Got kernel subimage data/size
700 -108 common/cmd_bootm.c Wrong image type (not legacy, FIT)
701 -109 common/cmd_bootm.c Can't get kernel subimage type
702 -110 common/cmd_bootm.c Can't get kernel subimage comp
703 -111 common/cmd_bootm.c Can't get kernel subimage os
704 -112 common/cmd_bootm.c Can't get kernel subimage load address
705 -113 common/cmd_bootm.c Image uncompress/copy overwrite error
706
707 120 common/image.c Start initial ramdisk verification
708 -120 common/image.c Ramdisk FIT image has incorrect format
709 121 common/image.c Ramdisk FIT image has correct format
710 122 common/image.c No ramdisk subimage unit name, using configuration
711 -122 common/image.c Can't get configuration for ramdisk subimage
712 123 common/image.c Ramdisk unit name specified
713 -124 common/image.c Can't get ramdisk subimage node offset
714 125 common/image.c Got ramdisk subimage node offset
715 -125 common/image.c Ramdisk subimage hash verification failed
716 126 common/image.c Ramdisk subimage hash verification OK
717 -126 common/image.c Ramdisk subimage for unsupported architecture
718 127 common/image.c Architecture check OK
719 -127 common/image.c Can't get ramdisk subimage data/size
720 128 common/image.c Got ramdisk subimage data/size
721 129 common/image.c Can't get ramdisk load address
722 -129 common/image.c Got ramdisk load address
723
724 -130 common/cmd_doc.c Incorrect FIT image format
725 131 common/cmd_doc.c FIT image format OK
726
727 -140 common/cmd_ide.c Incorrect FIT image format
728 141 common/cmd_ide.c FIT image format OK
729
730 -150 common/cmd_nand.c Incorrect FIT image format
731 151 common/cmd_nand.c FIT image format OK
732
Marek Vasut98154342021-10-23 03:06:03 +0200733config SPL_SHOW_BOOT_PROGRESS
Jan Kiszka5780edb2021-11-03 15:09:36 +0100734 bool "Show boot progress in a board-specific manner in SPL"
Marek Vasut98154342021-10-23 03:06:03 +0200735 depends on SPL
736 help
737 Defining this option allows to add some board-specific code (calling
738 a user-provided function show_boot_progress(int) that enables you to
739 show the system's boot progress on some display (for example, some
740 LEDs) on your board. For details see SHOW_BOOT_PROGRESS.
741
Simon Glassd02ddcf2020-09-10 20:21:14 -0600742endmenu
743
Simon Glasseebed782020-09-10 20:21:15 -0600744menu "Boot media"
745
746config NOR_BOOT
747 bool "Support for booting from NOR flash"
748 depends on NOR
749 help
750 Enabling this will make a U-Boot binary that is capable of being
751 booted via NOR. In this case we will enable certain pinmux early
752 as the ROM only partially sets up pinmux. We also default to using
753 NOR for environment.
754
755config NAND_BOOT
756 bool "Support for booting from NAND flash"
Simon Glasseebed782020-09-10 20:21:15 -0600757 imply MTD_RAW_NAND
758 help
759 Enabling this will make a U-Boot binary that is capable of being
760 booted via NAND flash. This is not a must, some SoCs need this,
761 some not.
762
763config ONENAND_BOOT
764 bool "Support for booting from ONENAND"
Simon Glasseebed782020-09-10 20:21:15 -0600765 imply MTD_RAW_NAND
766 help
767 Enabling this will make a U-Boot binary that is capable of being
768 booted via ONENAND. This is not a must, some SoCs need this,
769 some not.
770
771config QSPI_BOOT
772 bool "Support for booting from QSPI flash"
Simon Glasseebed782020-09-10 20:21:15 -0600773 help
774 Enabling this will make a U-Boot binary that is capable of being
775 booted via QSPI flash. This is not a must, some SoCs need this,
776 some not.
777
778config SATA_BOOT
779 bool "Support for booting from SATA"
Simon Glasseebed782020-09-10 20:21:15 -0600780 help
781 Enabling this will make a U-Boot binary that is capable of being
782 booted via SATA. This is not a must, some SoCs need this,
783 some not.
784
785config SD_BOOT
786 bool "Support for booting from SD/EMMC"
Simon Glasseebed782020-09-10 20:21:15 -0600787 help
788 Enabling this will make a U-Boot binary that is capable of being
789 booted via SD/EMMC. This is not a must, some SoCs need this,
790 some not.
791
Tom Rinia43bf4e2021-12-11 14:55:50 -0500792config SD_BOOT_QSPI
793 bool "Support for booting from SD/EMMC and enable QSPI"
794 help
795 Enabling this will make a U-Boot binary that is capable of being
796 booted via SD/EMMC while enabling QSPI on the platform as well. This
797 is not a must, some SoCs need this, some not.
798
Simon Glasseebed782020-09-10 20:21:15 -0600799config SPI_BOOT
800 bool "Support for booting from SPI flash"
Simon Glasseebed782020-09-10 20:21:15 -0600801 help
802 Enabling this will make a U-Boot binary that is capable of being
803 booted via SPI flash. This is not a must, some SoCs need this,
804 some not.
805
806endmenu
807
Simon Glasse9d54d72020-09-10 20:21:16 -0600808menu "Autoboot options"
809
810config AUTOBOOT
811 bool "Autoboot"
812 default y
813 help
814 This enables the autoboot. See doc/README.autoboot for detail.
815
Simon Glass1b6cbaa2020-09-10 20:21:17 -0600816config BOOTDELAY
817 int "delay in seconds before automatically booting"
818 default 2
819 depends on AUTOBOOT
820 help
821 Delay before automatically running bootcmd;
822 set to 0 to autoboot with no delay, but you can stop it by key input.
823 set to -1 to disable autoboot.
824 set to -2 to autoboot with no delay and not check for abort
825
826 If this value is >= 0 then it is also used for the default delay
827 before starting the default entry in bootmenu. If it is < 0 then
828 a default value of 10s is used.
829
830 See doc/README.autoboot for details.
831
Simon Glasse9d54d72020-09-10 20:21:16 -0600832config AUTOBOOT_KEYED
833 bool "Stop autobooting via specific input key / string"
Simon Glasse9d54d72020-09-10 20:21:16 -0600834 help
835 This option enables stopping (aborting) of the automatic
836 boot feature only by issuing a specific input key or
837 string. If not enabled, any input key will abort the
838 U-Boot automatic booting process and bring the device
839 to the U-Boot prompt for user input.
840
Steffen Jaeckeldfc97322021-07-08 15:57:38 +0200841config AUTOBOOT_FLUSH_STDIN
842 bool "Enable flushing stdin before starting to read the password"
843 depends on AUTOBOOT_KEYED && !SANDBOX
844 help
845 When this option is enabled stdin buffer will be flushed before
846 starting to read the password.
847 This can't be enabled for the sandbox as flushing stdin would
848 break the autoboot unit tests.
849
Simon Glasse9d54d72020-09-10 20:21:16 -0600850config AUTOBOOT_PROMPT
851 string "Autoboot stop prompt"
852 depends on AUTOBOOT_KEYED
853 default "Autoboot in %d seconds\\n"
854 help
855 This string is displayed before the boot delay selected by
856 CONFIG_BOOTDELAY starts. If it is not defined there is no
857 output indicating that autoboot is in progress.
858
859 Note that this define is used as the (only) argument to a
860 printf() call, so it may contain '%' format specifications,
861 provided that it also includes, sepearated by commas exactly
862 like in a printf statement, the required arguments. It is
863 the responsibility of the user to select only such arguments
864 that are valid in the given context.
865
866config AUTOBOOT_ENCRYPTION
867 bool "Enable encryption in autoboot stopping"
868 depends on AUTOBOOT_KEYED
869 help
870 This option allows a string to be entered into U-Boot to stop the
Steffen Jaeckel6aa6bfb2021-07-08 15:57:35 +0200871 autoboot.
872 The behavior depends whether CONFIG_CRYPT_PW from lib is enabled
873 or not.
874 In case CONFIG_CRYPT_PW is enabled, the string will be forwarded
875 to the crypt-based functionality and be compared against the
876 string in the environment variable 'bootstopkeycrypt'.
877 In case CONFIG_CRYPT_PW is disabled the string itself is hashed
878 and compared against the hash in the environment variable
879 'bootstopkeysha256'.
880 If it matches in either case then boot stops and
881 a command-line prompt is presented.
Simon Glasse9d54d72020-09-10 20:21:16 -0600882 This provides a way to ship a secure production device which can also
883 be accessed at the U-Boot command line.
884
Steffen Jaeckel28be70d2021-07-08 15:57:39 +0200885config AUTOBOOT_SHA256_FALLBACK
886 bool "Allow fallback from crypt-hashed password to sha256"
887 depends on AUTOBOOT_ENCRYPTION && CRYPT_PW
888 help
889 This option adds support to fall back from crypt-hashed
890 passwords to checking a SHA256 hashed password in case the
891 'bootstopusesha256' environment variable is set to 'true'.
892
Simon Glasse9d54d72020-09-10 20:21:16 -0600893config AUTOBOOT_DELAY_STR
894 string "Delay autobooting via specific input key / string"
895 depends on AUTOBOOT_KEYED && !AUTOBOOT_ENCRYPTION
896 help
897 This option delays the automatic boot feature by issuing
898 a specific input key or string. If CONFIG_AUTOBOOT_DELAY_STR
899 or the environment variable "bootdelaykey" is specified
900 and this string is received from console input before
901 autoboot starts booting, U-Boot gives a command prompt. The
902 U-Boot prompt will time out if CONFIG_BOOT_RETRY_TIME is
903 used, otherwise it never times out.
904
905config AUTOBOOT_STOP_STR
906 string "Stop autobooting via specific input key / string"
907 depends on AUTOBOOT_KEYED && !AUTOBOOT_ENCRYPTION
908 help
909 This option enables stopping (aborting) of the automatic
910 boot feature only by issuing a specific input key or
911 string. If CONFIG_AUTOBOOT_STOP_STR or the environment
912 variable "bootstopkey" is specified and this string is
913 received from console input before autoboot starts booting,
914 U-Boot gives a command prompt. The U-Boot prompt never
915 times out, even if CONFIG_BOOT_RETRY_TIME is used.
916
917config AUTOBOOT_KEYED_CTRLC
918 bool "Enable Ctrl-C autoboot interruption"
919 depends on AUTOBOOT_KEYED && !AUTOBOOT_ENCRYPTION
Simon Glasse9d54d72020-09-10 20:21:16 -0600920 help
921 This option allows for the boot sequence to be interrupted
922 by ctrl-c, in addition to the "bootdelaykey" and "bootstopkey".
923 Setting this variable provides an escape sequence from the
924 limited "password" strings.
925
Steffen Jaeckel792a13f2021-07-08 15:57:37 +0200926config AUTOBOOT_NEVER_TIMEOUT
927 bool "Make the password entry never time-out"
928 depends on AUTOBOOT_KEYED && AUTOBOOT_ENCRYPTION && CRYPT_PW
929 help
930 This option removes the timeout from the password entry
931 when the user first presses the <Enter> key before entering
932 any other character.
933
Steffen Jaeckel6aa6bfb2021-07-08 15:57:35 +0200934config AUTOBOOT_STOP_STR_ENABLE
935 bool "Enable fixed string to stop autobooting"
936 depends on AUTOBOOT_KEYED && AUTOBOOT_ENCRYPTION
937 help
938 This option enables the feature to add a fixed stop
939 string that is defined at compile time.
940 In every case it will be tried to load the stop
941 string from the environment.
942 In case this is enabled and there is no stop string
943 in the environment, this will be used as default value.
944
945config AUTOBOOT_STOP_STR_CRYPT
946 string "Stop autobooting via crypt-hashed password"
947 depends on AUTOBOOT_STOP_STR_ENABLE && CRYPT_PW
948 help
949 This option adds the feature to only stop the autobooting,
950 and therefore boot into the U-Boot prompt, when the input
951 string / password matches a values that is hashed via
952 one of the supported crypt-style password hashing options
953 and saved in the environment variable "bootstopkeycrypt".
954
Simon Glasse9d54d72020-09-10 20:21:16 -0600955config AUTOBOOT_STOP_STR_SHA256
Steffen Jaeckele1788f92021-07-08 15:57:40 +0200956 string "Stop autobooting via SHA256 hashed password"
Steffen Jaeckel6aa6bfb2021-07-08 15:57:35 +0200957 depends on AUTOBOOT_STOP_STR_ENABLE
Simon Glasse9d54d72020-09-10 20:21:16 -0600958 help
959 This option adds the feature to only stop the autobooting,
960 and therefore boot into the U-Boot prompt, when the input
961 string / password matches a values that is encypted via
Joel Peshkin8b7bf532020-11-21 17:18:59 -0800962 a SHA256 hash and saved in the environment variable
963 "bootstopkeysha256". If the value in that variable
964 includes a ":", the portion prior to the ":" will be treated
965 as a salt value.
Simon Glasse9d54d72020-09-10 20:21:16 -0600966
967config AUTOBOOT_USE_MENUKEY
968 bool "Allow a specify key to run a menu from the environment"
969 depends on !AUTOBOOT_KEYED
970 help
971 If a specific key is pressed to stop autoboot, then the commands in
972 the environment variable 'menucmd' are executed before boot starts.
973
974config AUTOBOOT_MENUKEY
975 int "ASCII value of boot key to show a menu"
976 default 0
977 depends on AUTOBOOT_USE_MENUKEY
978 help
979 If this key is pressed to stop autoboot, then the commands in the
980 environment variable 'menucmd' will be executed before boot starts.
981 For example, 33 means "!" in ASCII, so pressing ! at boot would take
982 this action.
983
984config AUTOBOOT_MENU_SHOW
985 bool "Show a menu on boot"
986 depends on CMD_BOOTMENU
987 help
988 This enables the boot menu, controlled by environment variables
989 defined by the board. The menu starts after running the 'preboot'
990 environmnent variable (if enabled) and before handling the boot delay.
991 See README.bootmenu for more details.
992
993endmenu
994
Simon Glass5e958642020-09-10 20:21:18 -0600995config USE_BOOTARGS
996 bool "Enable boot arguments"
997 help
998 Provide boot arguments to bootm command. Boot arguments are specified
999 in CONFIG_BOOTARGS option. Enable this option to be able to specify
1000 CONFIG_BOOTARGS string. If this option is disabled, CONFIG_BOOTARGS
1001 will be undefined and won't take any space in U-Boot image.
1002
1003config BOOTARGS
1004 string "Boot arguments"
1005 depends on USE_BOOTARGS && !USE_DEFAULT_ENV_FILE
1006 help
1007 This can be used to pass arguments to the bootm command. The value of
1008 CONFIG_BOOTARGS goes into the environment value "bootargs". Note that
1009 this value will also override the "chosen" node in FDT blob.
1010
Simon Glass529e2082020-11-05 10:33:48 -07001011config BOOTARGS_SUBST
1012 bool "Support substituting strings in boot arguments"
1013 help
1014 This allows substituting string values in the boot arguments. These
1015 are applied after the commandline has been built.
1016
1017 One use for this is to insert the root-disk UUID into the command
1018 line where bootargs contains "root=${uuid}"
1019
1020 setenv bootargs "console= root=${uuid}"
1021 # Set the 'uuid' environment variable
1022 part uuid mmc 2:2 uuid
1023
1024 # Command-line substitution will put the real uuid into the
1025 # kernel command line
1026 bootm
1027
Simon Glass5e958642020-09-10 20:21:18 -06001028config USE_BOOTCOMMAND
1029 bool "Enable a default value for bootcmd"
1030 help
1031 Provide a default value for the bootcmd entry in the environment. If
1032 autoboot is enabled this is what will be run automatically. Enable
1033 this option to be able to specify CONFIG_BOOTCOMMAND as a string. If
1034 this option is disabled, CONFIG_BOOTCOMMAND will be undefined and
1035 won't take any space in U-Boot image.
1036
1037config BOOTCOMMAND
1038 string "bootcmd value"
1039 depends on USE_BOOTCOMMAND && !USE_DEFAULT_ENV_FILE
1040 default "run distro_bootcmd" if DISTRO_DEFAULTS
1041 help
1042 This is the string of commands that will be used as bootcmd and if
1043 AUTOBOOT is set, automatically run.
1044
1045config USE_PREBOOT
1046 bool "Enable preboot"
1047 help
1048 When this option is enabled, the existence of the environment
1049 variable "preboot" will be checked immediately before starting the
1050 CONFIG_BOOTDELAY countdown and/or running the auto-boot command resp.
1051 entering interactive mode.
1052
1053 This feature is especially useful when "preboot" is automatically
1054 generated or modified. For example, the boot code can modify the
1055 "preboot" when a user holds down a certain combination of keys.
1056
1057config PREBOOT
1058 string "preboot default value"
1059 depends on USE_PREBOOT && !USE_DEFAULT_ENV_FILE
Patrick Delaunaybb15d402020-10-12 09:47:50 +02001060 default "usb start" if USB_KEYBOARD
Simon Glass5e958642020-09-10 20:21:18 -06001061 default ""
1062 help
1063 This is the default of "preboot" environment variable.
1064
Simon Glassc10ddfd2020-09-10 20:21:20 -06001065config DEFAULT_FDT_FILE
1066 string "Default fdt file"
1067 help
1068 This option is used to set the default fdt file to boot OS.
1069
Simon Glassb45b1632020-09-10 20:21:13 -06001070endmenu # Booting