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1 menu "x86 architecture"
2 depends on X86
3
4 config SYS_ARCH
5 default "x86"
6
7 choice
8 prompt "Run U-Boot in 32/64-bit mode"
9 default X86_RUN_32BIT
10 help
11 U-Boot can be built as a 32-bit binary which runs in 32-bit mode
12 even on 64-bit machines. In this case SPL is not used, and U-Boot
13 runs directly from the reset vector (via 16-bit start-up).
14
15 Alternatively it can be run as a 64-bit binary, thus requiring a
16 64-bit machine. In this case SPL runs in 32-bit mode (via 16-bit
17 start-up) then jumps to U-Boot in 64-bit mode.
18
19 For now, 32-bit mode is recommended, as 64-bit is still
20 experimental and is missing a lot of features.
21
22 config X86_RUN_32BIT
23 bool "32-bit"
24 help
25 Build U-Boot as a 32-bit binary with no SPL. This is the currently
26 supported normal setup. U-Boot will stay in 32-bit mode even on
27 64-bit machines. When booting a 64-bit kernel, U-Boot will switch
28 to 64-bit just before starting the kernel. Only the bottom 4GB of
29 memory can be accessed through normal means, although
30 arch_phys_memset() can be used for basic access to other memory.
31
32 config X86_RUN_64BIT
33 bool "64-bit"
34 select X86_64
35 select SUPPORT_SPL
36 select SPL
37 select SPL_SEPARATE_BSS
38 help
39 Build U-Boot as a 64-bit binary with a 32-bit SPL. This is
40 experimental and many features are missing. U-Boot SPL starts up,
41 runs through the 16-bit and 32-bit init, then switches to 64-bit
42 mode and jumps to U-Boot proper.
43
44 endchoice
45
46 config X86_64
47 bool
48
49 config SPL_X86_64
50 bool
51 depends on SPL
52
53 choice
54 prompt "Mainboard vendor"
55 default VENDOR_EMULATION
56
57 config VENDOR_ADVANTECH
58 bool "advantech"
59
60 config VENDOR_CONGATEC
61 bool "congatec"
62
63 config VENDOR_COREBOOT
64 bool "coreboot"
65
66 config VENDOR_DFI
67 bool "dfi"
68
69 config VENDOR_EFI
70 bool "efi"
71
72 config VENDOR_EMULATION
73 bool "emulation"
74
75 config VENDOR_GOOGLE
76 bool "Google"
77
78 config VENDOR_INTEL
79 bool "Intel"
80
81 endchoice
82
83 # subarchitectures-specific options below
84 config INTEL_MID
85 bool "Intel MID platform support"
86 select REGMAP
87 select SYSCON
88 help
89 Select to build a U-Boot capable of supporting Intel MID
90 (Mobile Internet Device) platform systems which do not have
91 the PCI legacy interfaces.
92
93 If you are building for a PC class system say N here.
94
95 Intel MID platforms are based on an Intel processor and
96 chipset which consume less power than most of the x86
97 derivatives.
98
99 # board-specific options below
100 source "board/advantech/Kconfig"
101 source "board/congatec/Kconfig"
102 source "board/coreboot/Kconfig"
103 source "board/dfi/Kconfig"
104 source "board/efi/Kconfig"
105 source "board/emulation/Kconfig"
106 source "board/google/Kconfig"
107 source "board/intel/Kconfig"
108
109 # platform-specific options below
110 source "arch/x86/cpu/baytrail/Kconfig"
111 source "arch/x86/cpu/broadwell/Kconfig"
112 source "arch/x86/cpu/coreboot/Kconfig"
113 source "arch/x86/cpu/ivybridge/Kconfig"
114 source "arch/x86/cpu/qemu/Kconfig"
115 source "arch/x86/cpu/quark/Kconfig"
116 source "arch/x86/cpu/queensbay/Kconfig"
117 source "arch/x86/cpu/tangier/Kconfig"
118
119 # architecture-specific options below
120
121 config AHCI
122 default y
123
124 config SYS_MALLOC_F_LEN
125 default 0x800
126
127 config RAMBASE
128 hex
129 default 0x100000
130
131 config XIP_ROM_SIZE
132 hex
133 depends on X86_RESET_VECTOR
134 default ROM_SIZE
135
136 config CPU_ADDR_BITS
137 int
138 default 36
139
140 config HPET_ADDRESS
141 hex
142 default 0xfed00000 if !HPET_ADDRESS_OVERRIDE
143
144 config SMM_TSEG
145 bool
146 default n
147
148 config SMM_TSEG_SIZE
149 hex
150
151 config X86_RESET_VECTOR
152 bool
153 default n
154
155 # The following options control where the 16-bit and 32-bit init lies
156 # If SPL is enabled then it normally holds this init code, and U-Boot proper
157 # is normally a 64-bit build.
158 #
159 # The 16-bit init refers to the reset vector and the small amount of code to
160 # get the processor into 32-bit mode. It may be in SPL or in U-Boot proper,
161 # or missing altogether if U-Boot is started from EFI or coreboot.
162 #
163 # The 32-bit init refers to processor init, running binary blobs including
164 # FSP, setting up interrupts and anything else that needs to be done in
165 # 32-bit code. It is normally in the same place as 16-bit init if that is
166 # enabled (i.e. they are both in SPL, or both in U-Boot proper).
167 config X86_16BIT_INIT
168 bool
169 depends on X86_RESET_VECTOR
170 default y if X86_RESET_VECTOR && !SPL
171 help
172 This is enabled when 16-bit init is in U-Boot proper
173
174 config SPL_X86_16BIT_INIT
175 bool
176 depends on X86_RESET_VECTOR
177 default y if X86_RESET_VECTOR && SPL
178 help
179 This is enabled when 16-bit init is in SPL
180
181 config X86_32BIT_INIT
182 bool
183 depends on X86_RESET_VECTOR
184 default y if X86_RESET_VECTOR && !SPL
185 help
186 This is enabled when 32-bit init is in U-Boot proper
187
188 config SPL_X86_32BIT_INIT
189 bool
190 depends on X86_RESET_VECTOR
191 default y if X86_RESET_VECTOR && SPL
192 help
193 This is enabled when 32-bit init is in SPL
194
195 config RESET_SEG_START
196 hex
197 depends on X86_RESET_VECTOR
198 default 0xffff0000
199
200 config RESET_SEG_SIZE
201 hex
202 depends on X86_RESET_VECTOR
203 default 0x10000
204
205 config RESET_VEC_LOC
206 hex
207 depends on X86_RESET_VECTOR
208 default 0xfffffff0
209
210 config SYS_X86_START16
211 hex
212 depends on X86_RESET_VECTOR
213 default 0xfffff800
214
215 config X86_LOAD_FROM_32_BIT
216 bool "Boot from a 32-bit program"
217 help
218 Define this to boot U-Boot from a 32-bit program which sets
219 the GDT differently. This can be used to boot directly from
220 any stage of coreboot, for example, bypassing the normal
221 payload-loading feature.
222
223 config BOARD_ROMSIZE_KB_512
224 bool
225 config BOARD_ROMSIZE_KB_1024
226 bool
227 config BOARD_ROMSIZE_KB_2048
228 bool
229 config BOARD_ROMSIZE_KB_4096
230 bool
231 config BOARD_ROMSIZE_KB_8192
232 bool
233 config BOARD_ROMSIZE_KB_16384
234 bool
235
236 choice
237 prompt "ROM chip size"
238 depends on X86_RESET_VECTOR
239 default UBOOT_ROMSIZE_KB_512 if BOARD_ROMSIZE_KB_512
240 default UBOOT_ROMSIZE_KB_1024 if BOARD_ROMSIZE_KB_1024
241 default UBOOT_ROMSIZE_KB_2048 if BOARD_ROMSIZE_KB_2048
242 default UBOOT_ROMSIZE_KB_4096 if BOARD_ROMSIZE_KB_4096
243 default UBOOT_ROMSIZE_KB_8192 if BOARD_ROMSIZE_KB_8192
244 default UBOOT_ROMSIZE_KB_16384 if BOARD_ROMSIZE_KB_16384
245 help
246 Select the size of the ROM chip you intend to flash U-Boot on.
247
248 The build system will take care of creating a u-boot.rom file
249 of the matching size.
250
251 config UBOOT_ROMSIZE_KB_512
252 bool "512 KB"
253 help
254 Choose this option if you have a 512 KB ROM chip.
255
256 config UBOOT_ROMSIZE_KB_1024
257 bool "1024 KB (1 MB)"
258 help
259 Choose this option if you have a 1024 KB (1 MB) ROM chip.
260
261 config UBOOT_ROMSIZE_KB_2048
262 bool "2048 KB (2 MB)"
263 help
264 Choose this option if you have a 2048 KB (2 MB) ROM chip.
265
266 config UBOOT_ROMSIZE_KB_4096
267 bool "4096 KB (4 MB)"
268 help
269 Choose this option if you have a 4096 KB (4 MB) ROM chip.
270
271 config UBOOT_ROMSIZE_KB_8192
272 bool "8192 KB (8 MB)"
273 help
274 Choose this option if you have a 8192 KB (8 MB) ROM chip.
275
276 config UBOOT_ROMSIZE_KB_16384
277 bool "16384 KB (16 MB)"
278 help
279 Choose this option if you have a 16384 KB (16 MB) ROM chip.
280
281 endchoice
282
283 # Map the config names to an integer (KB).
284 config UBOOT_ROMSIZE_KB
285 int
286 default 512 if UBOOT_ROMSIZE_KB_512
287 default 1024 if UBOOT_ROMSIZE_KB_1024
288 default 2048 if UBOOT_ROMSIZE_KB_2048
289 default 4096 if UBOOT_ROMSIZE_KB_4096
290 default 8192 if UBOOT_ROMSIZE_KB_8192
291 default 16384 if UBOOT_ROMSIZE_KB_16384
292
293 # Map the config names to a hex value (bytes).
294 config ROM_SIZE
295 hex
296 default 0x80000 if UBOOT_ROMSIZE_KB_512
297 default 0x100000 if UBOOT_ROMSIZE_KB_1024
298 default 0x200000 if UBOOT_ROMSIZE_KB_2048
299 default 0x400000 if UBOOT_ROMSIZE_KB_4096
300 default 0x800000 if UBOOT_ROMSIZE_KB_8192
301 default 0xc00000 if UBOOT_ROMSIZE_KB_12288
302 default 0x1000000 if UBOOT_ROMSIZE_KB_16384
303
304 config HAVE_INTEL_ME
305 bool "Platform requires Intel Management Engine"
306 help
307 Newer higher-end devices have an Intel Management Engine (ME)
308 which is a very large binary blob (typically 1.5MB) which is
309 required for the platform to work. This enforces a particular
310 SPI flash format. You will need to supply the me.bin file in
311 your board directory.
312
313 config X86_RAMTEST
314 bool "Perform a simple RAM test after SDRAM initialisation"
315 help
316 If there is something wrong with SDRAM then the platform will
317 often crash within U-Boot or the kernel. This option enables a
318 very simple RAM test that quickly checks whether the SDRAM seems
319 to work correctly. It is not exhaustive but can save time by
320 detecting obvious failures.
321
322 config FLASH_DESCRIPTOR_FILE
323 string "Flash descriptor binary filename"
324 depends on HAVE_INTEL_ME
325 default "descriptor.bin"
326 help
327 The filename of the file to use as flash descriptor in the
328 board directory.
329
330 config INTEL_ME_FILE
331 string "Intel Management Engine binary filename"
332 depends on HAVE_INTEL_ME
333 default "me.bin"
334 help
335 The filename of the file to use as Intel Management Engine in the
336 board directory.
337
338 config HAVE_FSP
339 bool "Add an Firmware Support Package binary"
340 depends on !EFI
341 help
342 Select this option to add an Firmware Support Package binary to
343 the resulting U-Boot image. It is a binary blob which U-Boot uses
344 to set up SDRAM and other chipset specific initialization.
345
346 Note: Without this binary U-Boot will not be able to set up its
347 SDRAM so will not boot.
348
349 config FSP_FILE
350 string "Firmware Support Package binary filename"
351 depends on HAVE_FSP
352 default "fsp.bin"
353 help
354 The filename of the file to use as Firmware Support Package binary
355 in the board directory.
356
357 config FSP_ADDR
358 hex "Firmware Support Package binary location"
359 depends on HAVE_FSP
360 default 0xfffc0000
361 help
362 FSP is not Position Independent Code (PIC) and the whole FSP has to
363 be rebased if it is placed at a location which is different from the
364 perferred base address specified during the FSP build. Use Intel's
365 Binary Configuration Tool (BCT) to do the rebase.
366
367 The default base address of 0xfffc0000 indicates that the binary must
368 be located at offset 0xc0000 from the beginning of a 1MB flash device.
369
370 config FSP_TEMP_RAM_ADDR
371 hex
372 depends on HAVE_FSP
373 default 0x2000000
374 help
375 Stack top address which is used in fsp_init() after DRAM is ready and
376 CAR is disabled.
377
378 config FSP_SYS_MALLOC_F_LEN
379 hex
380 depends on HAVE_FSP
381 default 0x100000
382 help
383 Additional size of malloc() pool before relocation.
384
385 config FSP_USE_UPD
386 bool
387 depends on HAVE_FSP
388 default y
389 help
390 Most FSPs use UPD data region for some FSP customization. But there
391 are still some FSPs that might not even have UPD. For such FSPs,
392 override this to n in their platform Kconfig files.
393
394 config FSP_BROKEN_HOB
395 bool
396 depends on HAVE_FSP
397 help
398 Indicate some buggy FSPs that does not report memory used by FSP
399 itself as reserved in the resource descriptor HOB. Select this to
400 tell U-Boot to do some additional work to ensure U-Boot relocation
401 do not overwrite the important boot service data which is used by
402 FSP, otherwise the subsequent call to fsp_notify() will fail.
403
404 config ENABLE_MRC_CACHE
405 bool "Enable MRC cache"
406 depends on !EFI && !SYS_COREBOOT
407 help
408 Enable this feature to cause MRC data to be cached in NV storage
409 to be used for speeding up boot time on future reboots and/or
410 power cycles.
411
412 For platforms that use Intel FSP for the memory initialization,
413 please check FSP output HOB via U-Boot command 'fsp hob' to see
414 if there is FSP_NON_VOLATILE_STORAGE_HOB_GUID (asm/fsp/fsp_hob.h).
415 If such GUID does not exist, MRC cache is not avaiable on such
416 platform (eg: Intel Queensbay), which means selecting this option
417 here does not make any difference.
418
419 config HAVE_MRC
420 bool "Add a System Agent binary"
421 depends on !HAVE_FSP
422 help
423 Select this option to add a System Agent binary to
424 the resulting U-Boot image. MRC stands for Memory Reference Code.
425 It is a binary blob which U-Boot uses to set up SDRAM.
426
427 Note: Without this binary U-Boot will not be able to set up its
428 SDRAM so will not boot.
429
430 config CACHE_MRC_BIN
431 bool
432 depends on HAVE_MRC
433 default n
434 help
435 Enable caching for the memory reference code binary. This uses an
436 MTRR (memory type range register) to turn on caching for the section
437 of SPI flash that contains the memory reference code. This makes
438 SDRAM init run faster.
439
440 config CACHE_MRC_SIZE_KB
441 int
442 depends on HAVE_MRC
443 default 512
444 help
445 Sets the size of the cached area for the memory reference code.
446 This ends at the end of SPI flash (address 0xffffffff) and is
447 measured in KB. Typically this is set to 512, providing for 0.5MB
448 of cached space.
449
450 config DCACHE_RAM_BASE
451 hex
452 depends on HAVE_MRC
453 help
454 Sets the base of the data cache area in memory space. This is the
455 start address of the cache-as-RAM (CAR) area and the address varies
456 depending on the CPU. Once CAR is set up, read/write memory becomes
457 available at this address and can be used temporarily until SDRAM
458 is working.
459
460 config DCACHE_RAM_SIZE
461 hex
462 depends on HAVE_MRC
463 default 0x40000
464 help
465 Sets the total size of the data cache area in memory space. This
466 sets the size of the cache-as-RAM (CAR) area. Note that much of the
467 CAR space is required by the MRC. The CAR space available to U-Boot
468 is normally at the start and typically extends to 1/4 or 1/2 of the
469 available size.
470
471 config DCACHE_RAM_MRC_VAR_SIZE
472 hex
473 depends on HAVE_MRC
474 help
475 This is the amount of CAR (Cache as RAM) reserved for use by the
476 memory reference code. This depends on the implementation of the
477 memory reference code and must be set correctly or the board will
478 not boot.
479
480 config HAVE_REFCODE
481 bool "Add a Reference Code binary"
482 help
483 Select this option to add a Reference Code binary to the resulting
484 U-Boot image. This is an Intel binary blob that handles system
485 initialisation, in this case the PCH and System Agent.
486
487 Note: Without this binary (on platforms that need it such as
488 broadwell) U-Boot will be missing some critical setup steps.
489 Various peripherals may fail to work.
490
491 config SMP
492 bool "Enable Symmetric Multiprocessing"
493 default n
494 help
495 Enable use of more than one CPU in U-Boot and the Operating System
496 when loaded. Each CPU will be started up and information can be
497 obtained using the 'cpu' command. If this option is disabled, then
498 only one CPU will be enabled regardless of the number of CPUs
499 available.
500
501 config MAX_CPUS
502 int "Maximum number of CPUs permitted"
503 depends on SMP
504 default 4
505 help
506 When using multi-CPU chips it is possible for U-Boot to start up
507 more than one CPU. The stack memory used by all of these CPUs is
508 pre-allocated so at present U-Boot wants to know the maximum
509 number of CPUs that may be present. Set this to at least as high
510 as the number of CPUs in your system (it uses about 4KB of RAM for
511 each CPU).
512
513 config AP_STACK_SIZE
514 hex
515 depends on SMP
516 default 0x1000
517 help
518 Each additional CPU started by U-Boot requires its own stack. This
519 option sets the stack size used by each CPU and directly affects
520 the memory used by this initialisation process. Typically 4KB is
521 enough space.
522
523 config HAVE_VGA_BIOS
524 bool "Add a VGA BIOS image"
525 help
526 Select this option if you have a VGA BIOS image that you would
527 like to add to your ROM.
528
529 config VGA_BIOS_FILE
530 string "VGA BIOS image filename"
531 depends on HAVE_VGA_BIOS
532 default "vga.bin"
533 help
534 The filename of the VGA BIOS image in the board directory.
535
536 config VGA_BIOS_ADDR
537 hex "VGA BIOS image location"
538 depends on HAVE_VGA_BIOS
539 default 0xfff90000
540 help
541 The location of VGA BIOS image in the SPI flash. For example, base
542 address of 0xfff90000 indicates that the image will be put at offset
543 0x90000 from the beginning of a 1MB flash device.
544
545 config ROM_TABLE_ADDR
546 hex
547 default 0xf0000
548 help
549 All x86 tables happen to like the address range from 0x0f0000
550 to 0x100000. We use 0xf0000 as the starting address to store
551 those tables, including PIRQ routing table, Multi-Processor
552 table and ACPI table.
553
554 config ROM_TABLE_SIZE
555 hex
556 default 0x10000
557
558 menu "System tables"
559 depends on !EFI && !SYS_COREBOOT
560
561 config GENERATE_PIRQ_TABLE
562 bool "Generate a PIRQ table"
563 default n
564 help
565 Generate a PIRQ routing table for this board. The PIRQ routing table
566 is generated by U-Boot in the system memory from 0xf0000 to 0xfffff
567 at every 16-byte boundary with a PCI IRQ routing signature ("$PIR").
568 It specifies the interrupt router information as well how all the PCI
569 devices' interrupt pins are wired to PIRQs.
570
571 config GENERATE_SFI_TABLE
572 bool "Generate a SFI (Simple Firmware Interface) table"
573 help
574 The Simple Firmware Interface (SFI) provides a lightweight method
575 for platform firmware to pass information to the operating system
576 via static tables in memory. Kernel SFI support is required to
577 boot on SFI-only platforms. If you have ACPI tables then these are
578 used instead.
579
580 U-Boot writes this table in write_sfi_table() just before booting
581 the OS.
582
583 For more information, see http://simplefirmware.org
584
585 config GENERATE_MP_TABLE
586 bool "Generate an MP (Multi-Processor) table"
587 default n
588 help
589 Generate an MP (Multi-Processor) table for this board. The MP table
590 provides a way for the operating system to support for symmetric
591 multiprocessing as well as symmetric I/O interrupt handling with
592 the local APIC and I/O APIC.
593
594 config GENERATE_ACPI_TABLE
595 bool "Generate an ACPI (Advanced Configuration and Power Interface) table"
596 default n
597 select QFW if QEMU
598 help
599 The Advanced Configuration and Power Interface (ACPI) specification
600 provides an open standard for device configuration and management
601 by the operating system. It defines platform-independent interfaces
602 for configuration and power management monitoring.
603
604 endmenu
605
606 config HAVE_ACPI_RESUME
607 bool "Enable ACPI S3 resume"
608 help
609 Select this to enable ACPI S3 resume. S3 is an ACPI-defined sleeping
610 state where all system context is lost except system memory. U-Boot
611 is responsible for restoring the machine state as it was before sleep.
612 It needs restore the memory controller, without overwriting memory
613 which is not marked as reserved. For the peripherals which lose their
614 registers, U-Boot needs to write the original value. When everything
615 is done, U-Boot needs to find out the wakeup vector provided by OSes
616 and jump there.
617
618 config S3_VGA_ROM_RUN
619 bool "Re-run VGA option ROMs on S3 resume"
620 depends on HAVE_ACPI_RESUME
621 default y if HAVE_ACPI_RESUME
622 help
623 Execute VGA option ROMs in U-Boot when resuming from S3. Normally
624 this is needed when graphics console is being used in the kernel.
625
626 Turning it off can reduce some resume time, but be aware that your
627 graphics console won't work without VGA options ROMs. Set it to N
628 if your kernel is only on a serial console.
629
630 config STACK_SIZE
631 hex
632 depends on HAVE_ACPI_RESUME
633 default 0x1000
634 help
635 Estimated U-Boot's runtime stack size that needs to be reserved
636 during an ACPI S3 resume.
637
638 config MAX_PIRQ_LINKS
639 int
640 default 8
641 help
642 This variable specifies the number of PIRQ interrupt links which are
643 routable. On most older chipsets, this is 4, PIRQA through PIRQD.
644 Some newer chipsets offer more than four links, commonly up to PIRQH.
645
646 config IRQ_SLOT_COUNT
647 int
648 default 128
649 help
650 U-Boot can support up to 254 IRQ slot info in the PIRQ routing table
651 which in turns forms a table of exact 4KiB. The default value 128
652 should be enough for most boards. If this does not fit your board,
653 change it according to your needs.
654
655 config PCIE_ECAM_BASE
656 hex
657 default 0xe0000000
658 help
659 This is the memory-mapped address of PCI configuration space, which
660 is only available through the Enhanced Configuration Access
661 Mechanism (ECAM) with PCI Express. It can be set up almost
662 anywhere. Before it is set up, it is possible to access PCI
663 configuration space through I/O access, but memory access is more
664 convenient. Using this, PCI can be scanned and configured. This
665 should be set to a region that does not conflict with memory
666 assigned to PCI devices - i.e. the memory and prefetch regions, as
667 passed to pci_set_region().
668
669 config PCIE_ECAM_SIZE
670 hex
671 default 0x10000000
672 help
673 This is the size of memory-mapped address of PCI configuration space,
674 which is only available through the Enhanced Configuration Access
675 Mechanism (ECAM) with PCI Express. Each bus consumes 1 MiB memory,
676 so a default 0x10000000 size covers all of the 256 buses which is the
677 maximum number of PCI buses as defined by the PCI specification.
678
679 config I8259_PIC
680 bool
681 default y
682 help
683 Intel 8259 ISA compatible chipset incorporates two 8259 (master and
684 slave) interrupt controllers. Include this to have U-Boot set up
685 the interrupt correctly.
686
687 config I8254_TIMER
688 bool
689 default y
690 help
691 Intel 8254 timer contains three counters which have fixed uses.
692 Include this to have U-Boot set up the timer correctly.
693
694 config SEABIOS
695 bool "Support booting SeaBIOS"
696 help
697 SeaBIOS is an open source implementation of a 16-bit X86 BIOS.
698 It can run in an emulator or natively on X86 hardware with the use
699 of coreboot/U-Boot. By turning on this option, U-Boot prepares
700 all the configuration tables that are necessary to boot SeaBIOS.
701
702 Check http://www.seabios.org/SeaBIOS for details.
703
704 config HIGH_TABLE_SIZE
705 hex "Size of configuration tables which reside in high memory"
706 default 0x10000
707 depends on SEABIOS
708 help
709 SeaBIOS itself resides in E seg and F seg, where U-Boot puts all
710 configuration tables like PIRQ/MP/ACPI. To avoid conflicts, U-Boot
711 puts a copy of configuration tables in high memory region which
712 is reserved on the stack before relocation. The region size is
713 determined by this option.
714
715 Increse it if the default size does not fit the board's needs.
716 This is most likely due to a large ACPI DSDT table is used.
717
718 source "arch/x86/lib/efi/Kconfig"
719
720 endmenu