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Merge branches 'pm-cpufreq', 'pm-sleep' and 'pm-em'
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1 # SPDX-License-Identifier: GPL-2.0
2 config ARM
3 bool
4 default y
5 select ARCH_32BIT_OFF_T
6 select ARCH_HAS_BINFMT_FLAT
7 select ARCH_HAS_DEBUG_VIRTUAL if MMU
8 select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE
9 select ARCH_HAS_ELF_RANDOMIZE
10 select ARCH_HAS_FORTIFY_SOURCE
11 select ARCH_HAS_KEEPINITRD
12 select ARCH_HAS_KCOV
13 select ARCH_HAS_MEMBARRIER_SYNC_CORE
14 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
15 select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
16 select ARCH_HAS_PHYS_TO_DMA
17 select ARCH_HAS_SETUP_DMA_OPS
18 select ARCH_HAS_SET_MEMORY
19 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
20 select ARCH_HAS_STRICT_MODULE_RWX if MMU
21 select ARCH_HAS_SYNC_DMA_FOR_DEVICE if SWIOTLB || !MMU
22 select ARCH_HAS_SYNC_DMA_FOR_CPU if SWIOTLB || !MMU
23 select ARCH_HAS_TEARDOWN_DMA_OPS if MMU
24 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
25 select ARCH_HAVE_CUSTOM_GPIO_H
26 select ARCH_HAVE_NMI_SAFE_CMPXCHG if CPU_V7 || CPU_V7M || CPU_V6K
27 select ARCH_HAS_GCOV_PROFILE_ALL
28 select ARCH_KEEP_MEMBLOCK
29 select ARCH_MIGHT_HAVE_PC_PARPORT
30 select ARCH_NO_SG_CHAIN if !ARM_HAS_SG_CHAIN
31 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
32 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
33 select ARCH_SUPPORTS_ATOMIC_RMW
34 select ARCH_SUPPORTS_HUGETLBFS if ARM_LPAE
35 select ARCH_USE_BUILTIN_BSWAP
36 select ARCH_USE_CMPXCHG_LOCKREF
37 select ARCH_USE_MEMTEST
38 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
39 select ARCH_WANT_IPC_PARSE_VERSION
40 select ARCH_WANT_LD_ORPHAN_WARN
41 select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
42 select BUILDTIME_TABLE_SORT if MMU
43 select CLONE_BACKWARDS
44 select CPU_PM if SUSPEND || CPU_IDLE
45 select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
46 select DMA_DECLARE_COHERENT
47 select DMA_GLOBAL_POOL if !MMU
48 select DMA_OPS
49 select DMA_REMAP if MMU
50 select EDAC_SUPPORT
51 select EDAC_ATOMIC_SCRUB
52 select GENERIC_ALLOCATOR
53 select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
54 select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
55 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
56 select GENERIC_IRQ_IPI if SMP
57 select GENERIC_CPU_AUTOPROBE
58 select GENERIC_EARLY_IOREMAP
59 select GENERIC_IDLE_POLL_SETUP
60 select GENERIC_IRQ_PROBE
61 select GENERIC_IRQ_SHOW
62 select GENERIC_IRQ_SHOW_LEVEL
63 select GENERIC_LIB_DEVMEM_IS_ALLOWED
64 select GENERIC_PCI_IOMAP
65 select GENERIC_SCHED_CLOCK
66 select GENERIC_SMP_IDLE_THREAD
67 select HANDLE_DOMAIN_IRQ
68 select HARDIRQS_SW_RESEND
69 select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
70 select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
71 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
72 select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
73 select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
74 select HAVE_ARCH_MMAP_RND_BITS if MMU
75 select HAVE_ARCH_PFN_VALID
76 select HAVE_ARCH_SECCOMP
77 select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT
78 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
79 select HAVE_ARCH_TRACEHOOK
80 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARM_LPAE
81 select HAVE_ARM_SMCCC if CPU_V7
82 select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
83 select HAVE_CONTEXT_TRACKING
84 select HAVE_C_RECORDMCOUNT
85 select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL
86 select HAVE_DMA_CONTIGUOUS if MMU
87 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
88 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
89 select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
90 select HAVE_EXIT_THREAD
91 select HAVE_FAST_GUP if ARM_LPAE
92 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
93 select HAVE_FUNCTION_GRAPH_TRACER if !THUMB2_KERNEL && !CC_IS_CLANG
94 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
95 select HAVE_GCC_PLUGINS
96 select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7)
97 select HAVE_IRQ_TIME_ACCOUNTING
98 select HAVE_KERNEL_GZIP
99 select HAVE_KERNEL_LZ4
100 select HAVE_KERNEL_LZMA
101 select HAVE_KERNEL_LZO
102 select HAVE_KERNEL_XZ
103 select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
104 select HAVE_KRETPROBES if HAVE_KPROBES
105 select HAVE_MOD_ARCH_SPECIFIC
106 select HAVE_NMI
107 select HAVE_OPTPROBES if !THUMB2_KERNEL
108 select HAVE_PERF_EVENTS
109 select HAVE_PERF_REGS
110 select HAVE_PERF_USER_STACK_DUMP
111 select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
112 select HAVE_REGS_AND_STACK_ACCESS_API
113 select HAVE_RSEQ
114 select HAVE_STACKPROTECTOR
115 select HAVE_SYSCALL_TRACEPOINTS
116 select HAVE_UID16
117 select HAVE_VIRT_CPU_ACCOUNTING_GEN
118 select IRQ_FORCED_THREADING
119 select MODULES_USE_ELF_REL
120 select NEED_DMA_MAP_STATE
121 select OF_EARLY_FLATTREE if OF
122 select OLD_SIGACTION
123 select OLD_SIGSUSPEND3
124 select PCI_SYSCALL if PCI
125 select PERF_USE_VMALLOC
126 select RTC_LIB
127 select SET_FS
128 select SYS_SUPPORTS_APM_EMULATION
129 select TRACE_IRQFLAGS_SUPPORT if !CPU_V7M
130 # Above selects are sorted alphabetically; please add new ones
131 # according to that. Thanks.
132 help
133 The ARM series is a line of low-power-consumption RISC chip designs
134 licensed by ARM Ltd and targeted at embedded applications and
135 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
136 manufactured, but legacy ARM-based PC hardware remains popular in
137 Europe. There is an ARM Linux project with a web page at
138 <http://www.arm.linux.org.uk/>.
139
140 config ARM_HAS_SG_CHAIN
141 bool
142
143 config ARM_DMA_USE_IOMMU
144 bool
145 select ARM_HAS_SG_CHAIN
146 select NEED_SG_DMA_LENGTH
147
148 if ARM_DMA_USE_IOMMU
149
150 config ARM_DMA_IOMMU_ALIGNMENT
151 int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
152 range 4 9
153 default 8
154 help
155 DMA mapping framework by default aligns all buffers to the smallest
156 PAGE_SIZE order which is greater than or equal to the requested buffer
157 size. This works well for buffers up to a few hundreds kilobytes, but
158 for larger buffers it just a waste of address space. Drivers which has
159 relatively small addressing window (like 64Mib) might run out of
160 virtual space with just a few allocations.
161
162 With this parameter you can specify the maximum PAGE_SIZE order for
163 DMA IOMMU buffers. Larger buffers will be aligned only to this
164 specified order. The order is expressed as a power of two multiplied
165 by the PAGE_SIZE.
166
167 endif
168
169 config SYS_SUPPORTS_APM_EMULATION
170 bool
171
172 config HAVE_TCM
173 bool
174 select GENERIC_ALLOCATOR
175
176 config HAVE_PROC_CPU
177 bool
178
179 config NO_IOPORT_MAP
180 bool
181
182 config SBUS
183 bool
184
185 config STACKTRACE_SUPPORT
186 bool
187 default y
188
189 config LOCKDEP_SUPPORT
190 bool
191 default y
192
193 config ARCH_HAS_ILOG2_U32
194 bool
195
196 config ARCH_HAS_ILOG2_U64
197 bool
198
199 config ARCH_HAS_BANDGAP
200 bool
201
202 config FIX_EARLYCON_MEM
203 def_bool y if MMU
204
205 config GENERIC_HWEIGHT
206 bool
207 default y
208
209 config GENERIC_CALIBRATE_DELAY
210 bool
211 default y
212
213 config ARCH_MAY_HAVE_PC_FDC
214 bool
215
216 config ARCH_SUPPORTS_UPROBES
217 def_bool y
218
219 config ARCH_HAS_DMA_SET_COHERENT_MASK
220 bool
221
222 config GENERIC_ISA_DMA
223 bool
224
225 config FIQ
226 bool
227
228 config NEED_RET_TO_USER
229 bool
230
231 config ARCH_MTD_XIP
232 bool
233
234 config ARM_PATCH_PHYS_VIRT
235 bool "Patch physical to virtual translations at runtime" if EMBEDDED
236 default y
237 depends on !XIP_KERNEL && MMU
238 help
239 Patch phys-to-virt and virt-to-phys translation functions at
240 boot and module load time according to the position of the
241 kernel in system memory.
242
243 This can only be used with non-XIP MMU kernels where the base
244 of physical memory is at a 2 MiB boundary.
245
246 Only disable this option if you know that you do not require
247 this feature (eg, building a kernel for a single machine) and
248 you need to shrink the kernel to the minimal size.
249
250 config NEED_MACH_IO_H
251 bool
252 help
253 Select this when mach/io.h is required to provide special
254 definitions for this platform. The need for mach/io.h should
255 be avoided when possible.
256
257 config NEED_MACH_MEMORY_H
258 bool
259 help
260 Select this when mach/memory.h is required to provide special
261 definitions for this platform. The need for mach/memory.h should
262 be avoided when possible.
263
264 config PHYS_OFFSET
265 hex "Physical address of main memory" if MMU
266 depends on !ARM_PATCH_PHYS_VIRT
267 default DRAM_BASE if !MMU
268 default 0x00000000 if ARCH_FOOTBRIDGE
269 default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
270 default 0x20000000 if ARCH_S5PV210
271 default 0xc0000000 if ARCH_SA1100
272 help
273 Please provide the physical address corresponding to the
274 location of main memory in your system.
275
276 config GENERIC_BUG
277 def_bool y
278 depends on BUG
279
280 config PGTABLE_LEVELS
281 int
282 default 3 if ARM_LPAE
283 default 2
284
285 menu "System Type"
286
287 config MMU
288 bool "MMU-based Paged Memory Management Support"
289 default y
290 help
291 Select if you want MMU-based virtualised addressing space
292 support by paged memory management. If unsure, say 'Y'.
293
294 config ARCH_MMAP_RND_BITS_MIN
295 default 8
296
297 config ARCH_MMAP_RND_BITS_MAX
298 default 14 if PAGE_OFFSET=0x40000000
299 default 15 if PAGE_OFFSET=0x80000000
300 default 16
301
302 #
303 # The "ARM system type" choice list is ordered alphabetically by option
304 # text. Please add new entries in the option alphabetic order.
305 #
306 choice
307 prompt "ARM system type"
308 default ARM_SINGLE_ARMV7M if !MMU
309 default ARCH_MULTIPLATFORM if MMU
310
311 config ARCH_MULTIPLATFORM
312 bool "Allow multiple platforms to be selected"
313 depends on MMU
314 select ARCH_FLATMEM_ENABLE
315 select ARCH_SPARSEMEM_ENABLE
316 select ARCH_SELECT_MEMORY_MODEL
317 select ARM_HAS_SG_CHAIN
318 select ARM_PATCH_PHYS_VIRT
319 select AUTO_ZRELADDR
320 select TIMER_OF
321 select COMMON_CLK
322 select GENERIC_IRQ_MULTI_HANDLER
323 select HAVE_PCI
324 select PCI_DOMAINS_GENERIC if PCI
325 select SPARSE_IRQ
326 select USE_OF
327
328 config ARM_SINGLE_ARMV7M
329 bool "ARMv7-M based platforms (Cortex-M0/M3/M4)"
330 depends on !MMU
331 select ARM_NVIC
332 select AUTO_ZRELADDR
333 select TIMER_OF
334 select COMMON_CLK
335 select CPU_V7M
336 select NO_IOPORT_MAP
337 select SPARSE_IRQ
338 select USE_OF
339
340 config ARCH_EP93XX
341 bool "EP93xx-based"
342 select ARCH_SPARSEMEM_ENABLE
343 select ARM_AMBA
344 imply ARM_PATCH_PHYS_VIRT
345 select ARM_VIC
346 select GENERIC_IRQ_MULTI_HANDLER
347 select AUTO_ZRELADDR
348 select CLKSRC_MMIO
349 select CPU_ARM920T
350 select GPIOLIB
351 select HAVE_LEGACY_CLK
352 help
353 This enables support for the Cirrus EP93xx series of CPUs.
354
355 config ARCH_FOOTBRIDGE
356 bool "FootBridge"
357 select CPU_SA110
358 select FOOTBRIDGE
359 select NEED_MACH_IO_H if !MMU
360 select NEED_MACH_MEMORY_H
361 help
362 Support for systems based on the DC21285 companion chip
363 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
364
365 config ARCH_IOP32X
366 bool "IOP32x-based"
367 depends on MMU
368 select CPU_XSCALE
369 select GPIO_IOP
370 select GPIOLIB
371 select NEED_RET_TO_USER
372 select FORCE_PCI
373 select PLAT_IOP
374 help
375 Support for Intel's 80219 and IOP32X (XScale) family of
376 processors.
377
378 config ARCH_IXP4XX
379 bool "IXP4xx-based"
380 depends on MMU
381 select ARCH_HAS_DMA_SET_COHERENT_MASK
382 select ARCH_SUPPORTS_BIG_ENDIAN
383 select CPU_XSCALE
384 select DMABOUNCE if PCI
385 select GENERIC_IRQ_MULTI_HANDLER
386 select GPIO_IXP4XX
387 select GPIOLIB
388 select HAVE_PCI
389 select IXP4XX_IRQ
390 select IXP4XX_TIMER
391 # With the new PCI driver this is not needed
392 select NEED_MACH_IO_H if IXP4XX_PCI_LEGACY
393 select USB_EHCI_BIG_ENDIAN_DESC
394 select USB_EHCI_BIG_ENDIAN_MMIO
395 help
396 Support for Intel's IXP4XX (XScale) family of processors.
397
398 config ARCH_DOVE
399 bool "Marvell Dove"
400 select CPU_PJ4
401 select GENERIC_IRQ_MULTI_HANDLER
402 select GPIOLIB
403 select HAVE_PCI
404 select MVEBU_MBUS
405 select PINCTRL
406 select PINCTRL_DOVE
407 select PLAT_ORION_LEGACY
408 select SPARSE_IRQ
409 select PM_GENERIC_DOMAINS if PM
410 help
411 Support for the Marvell Dove SoC 88AP510
412
413 config ARCH_PXA
414 bool "PXA2xx/PXA3xx-based"
415 depends on MMU
416 select ARCH_MTD_XIP
417 select ARM_CPU_SUSPEND if PM
418 select AUTO_ZRELADDR
419 select COMMON_CLK
420 select CLKSRC_PXA
421 select CLKSRC_MMIO
422 select TIMER_OF
423 select CPU_XSCALE if !CPU_XSC3
424 select GENERIC_IRQ_MULTI_HANDLER
425 select GPIO_PXA
426 select GPIOLIB
427 select IRQ_DOMAIN
428 select PLAT_PXA
429 select SPARSE_IRQ
430 help
431 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
432
433 config ARCH_RPC
434 bool "RiscPC"
435 depends on MMU
436 select ARCH_ACORN
437 select ARCH_MAY_HAVE_PC_FDC
438 select ARCH_SPARSEMEM_ENABLE
439 select ARM_HAS_SG_CHAIN
440 select CPU_SA110
441 select FIQ
442 select HAVE_PATA_PLATFORM
443 select ISA_DMA_API
444 select LEGACY_TIMER_TICK
445 select NEED_MACH_IO_H
446 select NEED_MACH_MEMORY_H
447 select NO_IOPORT_MAP
448 help
449 On the Acorn Risc-PC, Linux can support the internal IDE disk and
450 CD-ROM interface, serial and parallel port, and the floppy drive.
451
452 config ARCH_SA1100
453 bool "SA1100-based"
454 select ARCH_MTD_XIP
455 select ARCH_SPARSEMEM_ENABLE
456 select CLKSRC_MMIO
457 select CLKSRC_PXA
458 select TIMER_OF if OF
459 select COMMON_CLK
460 select CPU_FREQ
461 select CPU_SA1100
462 select GENERIC_IRQ_MULTI_HANDLER
463 select GPIOLIB
464 select IRQ_DOMAIN
465 select ISA
466 select NEED_MACH_MEMORY_H
467 select SPARSE_IRQ
468 help
469 Support for StrongARM 11x0 based boards.
470
471 config ARCH_S3C24XX
472 bool "Samsung S3C24XX SoCs"
473 select ATAGS
474 select CLKSRC_SAMSUNG_PWM
475 select GPIO_SAMSUNG
476 select GPIOLIB
477 select GENERIC_IRQ_MULTI_HANDLER
478 select HAVE_S3C2410_I2C if I2C
479 select HAVE_S3C_RTC if RTC_CLASS
480 select NEED_MACH_IO_H
481 select S3C2410_WATCHDOG
482 select SAMSUNG_ATAGS
483 select USE_OF
484 select WATCHDOG
485 help
486 Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443
487 and S3C2450 SoCs based systems, such as the Simtec Electronics BAST
488 (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or the
489 Samsung SMDK2410 development board (and derivatives).
490
491 config ARCH_OMAP1
492 bool "TI OMAP1"
493 depends on MMU
494 select ARCH_OMAP
495 select CLKSRC_MMIO
496 select GENERIC_IRQ_CHIP
497 select GENERIC_IRQ_MULTI_HANDLER
498 select GPIOLIB
499 select HAVE_LEGACY_CLK
500 select IRQ_DOMAIN
501 select NEED_MACH_IO_H if PCCARD
502 select NEED_MACH_MEMORY_H
503 select SPARSE_IRQ
504 help
505 Support for older TI OMAP1 (omap7xx, omap15xx or omap16xx)
506
507 endchoice
508
509 menu "Multiple platform selection"
510 depends on ARCH_MULTIPLATFORM
511
512 comment "CPU Core family selection"
513
514 config ARCH_MULTI_V4
515 bool "ARMv4 based platforms (FA526)"
516 depends on !ARCH_MULTI_V6_V7
517 select ARCH_MULTI_V4_V5
518 select CPU_FA526
519
520 config ARCH_MULTI_V4T
521 bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
522 depends on !ARCH_MULTI_V6_V7
523 select ARCH_MULTI_V4_V5
524 select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
525 CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
526 CPU_ARM925T || CPU_ARM940T)
527
528 config ARCH_MULTI_V5
529 bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
530 depends on !ARCH_MULTI_V6_V7
531 select ARCH_MULTI_V4_V5
532 select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
533 CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
534 CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
535
536 config ARCH_MULTI_V4_V5
537 bool
538
539 config ARCH_MULTI_V6
540 bool "ARMv6 based platforms (ARM11)"
541 select ARCH_MULTI_V6_V7
542 select CPU_V6K
543
544 config ARCH_MULTI_V7
545 bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
546 default y
547 select ARCH_MULTI_V6_V7
548 select CPU_V7
549 select HAVE_SMP
550
551 config ARCH_MULTI_V6_V7
552 bool
553 select MIGHT_HAVE_CACHE_L2X0
554
555 config ARCH_MULTI_CPU_AUTO
556 def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
557 select ARCH_MULTI_V5
558
559 endmenu
560
561 config ARCH_VIRT
562 bool "Dummy Virtual Machine"
563 depends on ARCH_MULTI_V7
564 select ARM_AMBA
565 select ARM_GIC
566 select ARM_GIC_V2M if PCI
567 select ARM_GIC_V3
568 select ARM_GIC_V3_ITS if PCI
569 select ARM_PSCI
570 select HAVE_ARM_ARCH_TIMER
571 select ARCH_SUPPORTS_BIG_ENDIAN
572
573 #
574 # This is sorted alphabetically by mach-* pathname. However, plat-*
575 # Kconfigs may be included either alphabetically (according to the
576 # plat- suffix) or along side the corresponding mach-* source.
577 #
578 source "arch/arm/mach-actions/Kconfig"
579
580 source "arch/arm/mach-alpine/Kconfig"
581
582 source "arch/arm/mach-artpec/Kconfig"
583
584 source "arch/arm/mach-asm9260/Kconfig"
585
586 source "arch/arm/mach-aspeed/Kconfig"
587
588 source "arch/arm/mach-at91/Kconfig"
589
590 source "arch/arm/mach-axxia/Kconfig"
591
592 source "arch/arm/mach-bcm/Kconfig"
593
594 source "arch/arm/mach-berlin/Kconfig"
595
596 source "arch/arm/mach-clps711x/Kconfig"
597
598 source "arch/arm/mach-cns3xxx/Kconfig"
599
600 source "arch/arm/mach-davinci/Kconfig"
601
602 source "arch/arm/mach-digicolor/Kconfig"
603
604 source "arch/arm/mach-dove/Kconfig"
605
606 source "arch/arm/mach-ep93xx/Kconfig"
607
608 source "arch/arm/mach-exynos/Kconfig"
609
610 source "arch/arm/mach-footbridge/Kconfig"
611
612 source "arch/arm/mach-gemini/Kconfig"
613
614 source "arch/arm/mach-highbank/Kconfig"
615
616 source "arch/arm/mach-hisi/Kconfig"
617
618 source "arch/arm/mach-imx/Kconfig"
619
620 source "arch/arm/mach-integrator/Kconfig"
621
622 source "arch/arm/mach-iop32x/Kconfig"
623
624 source "arch/arm/mach-ixp4xx/Kconfig"
625
626 source "arch/arm/mach-keystone/Kconfig"
627
628 source "arch/arm/mach-lpc32xx/Kconfig"
629
630 source "arch/arm/mach-mediatek/Kconfig"
631
632 source "arch/arm/mach-meson/Kconfig"
633
634 source "arch/arm/mach-milbeaut/Kconfig"
635
636 source "arch/arm/mach-mmp/Kconfig"
637
638 source "arch/arm/mach-moxart/Kconfig"
639
640 source "arch/arm/mach-mstar/Kconfig"
641
642 source "arch/arm/mach-mv78xx0/Kconfig"
643
644 source "arch/arm/mach-mvebu/Kconfig"
645
646 source "arch/arm/mach-mxs/Kconfig"
647
648 source "arch/arm/mach-nomadik/Kconfig"
649
650 source "arch/arm/mach-npcm/Kconfig"
651
652 source "arch/arm/mach-nspire/Kconfig"
653
654 source "arch/arm/plat-omap/Kconfig"
655
656 source "arch/arm/mach-omap1/Kconfig"
657
658 source "arch/arm/mach-omap2/Kconfig"
659
660 source "arch/arm/mach-orion5x/Kconfig"
661
662 source "arch/arm/mach-oxnas/Kconfig"
663
664 source "arch/arm/mach-pxa/Kconfig"
665 source "arch/arm/plat-pxa/Kconfig"
666
667 source "arch/arm/mach-qcom/Kconfig"
668
669 source "arch/arm/mach-rda/Kconfig"
670
671 source "arch/arm/mach-realtek/Kconfig"
672
673 source "arch/arm/mach-realview/Kconfig"
674
675 source "arch/arm/mach-rockchip/Kconfig"
676
677 source "arch/arm/mach-s3c/Kconfig"
678
679 source "arch/arm/mach-s5pv210/Kconfig"
680
681 source "arch/arm/mach-sa1100/Kconfig"
682
683 source "arch/arm/mach-shmobile/Kconfig"
684
685 source "arch/arm/mach-socfpga/Kconfig"
686
687 source "arch/arm/mach-spear/Kconfig"
688
689 source "arch/arm/mach-sti/Kconfig"
690
691 source "arch/arm/mach-stm32/Kconfig"
692
693 source "arch/arm/mach-sunxi/Kconfig"
694
695 source "arch/arm/mach-tegra/Kconfig"
696
697 source "arch/arm/mach-uniphier/Kconfig"
698
699 source "arch/arm/mach-ux500/Kconfig"
700
701 source "arch/arm/mach-versatile/Kconfig"
702
703 source "arch/arm/mach-vexpress/Kconfig"
704
705 source "arch/arm/mach-vt8500/Kconfig"
706
707 source "arch/arm/mach-zynq/Kconfig"
708
709 # ARMv7-M architecture
710 config ARCH_LPC18XX
711 bool "NXP LPC18xx/LPC43xx"
712 depends on ARM_SINGLE_ARMV7M
713 select ARCH_HAS_RESET_CONTROLLER
714 select ARM_AMBA
715 select CLKSRC_LPC32XX
716 select PINCTRL
717 help
718 Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
719 high performance microcontrollers.
720
721 config ARCH_MPS2
722 bool "ARM MPS2 platform"
723 depends on ARM_SINGLE_ARMV7M
724 select ARM_AMBA
725 select CLKSRC_MPS2
726 help
727 Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
728 with a range of available cores like Cortex-M3/M4/M7.
729
730 Please, note that depends which Application Note is used memory map
731 for the platform may vary, so adjustment of RAM base might be needed.
732
733 # Definitions to make life easier
734 config ARCH_ACORN
735 bool
736
737 config PLAT_IOP
738 bool
739
740 config PLAT_ORION
741 bool
742 select CLKSRC_MMIO
743 select COMMON_CLK
744 select GENERIC_IRQ_CHIP
745 select IRQ_DOMAIN
746
747 config PLAT_ORION_LEGACY
748 bool
749 select PLAT_ORION
750
751 config PLAT_PXA
752 bool
753
754 config PLAT_VERSATILE
755 bool
756
757 source "arch/arm/mm/Kconfig"
758
759 config IWMMXT
760 bool "Enable iWMMXt support"
761 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
762 default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
763 help
764 Enable support for iWMMXt context switching at run time if
765 running on a CPU that supports it.
766
767 if !MMU
768 source "arch/arm/Kconfig-nommu"
769 endif
770
771 config PJ4B_ERRATA_4742
772 bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
773 depends on CPU_PJ4B && MACH_ARMADA_370
774 default y
775 help
776 When coming out of either a Wait for Interrupt (WFI) or a Wait for
777 Event (WFE) IDLE states, a specific timing sensitivity exists between
778 the retiring WFI/WFE instructions and the newly issued subsequent
779 instructions. This sensitivity can result in a CPU hang scenario.
780 Workaround:
781 The software must insert either a Data Synchronization Barrier (DSB)
782 or Data Memory Barrier (DMB) command immediately after the WFI/WFE
783 instruction
784
785 config ARM_ERRATA_326103
786 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
787 depends on CPU_V6
788 help
789 Executing a SWP instruction to read-only memory does not set bit 11
790 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
791 treat the access as a read, preventing a COW from occurring and
792 causing the faulting task to livelock.
793
794 config ARM_ERRATA_411920
795 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
796 depends on CPU_V6 || CPU_V6K
797 help
798 Invalidation of the Instruction Cache operation can
799 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
800 It does not affect the MPCore. This option enables the ARM Ltd.
801 recommended workaround.
802
803 config ARM_ERRATA_430973
804 bool "ARM errata: Stale prediction on replaced interworking branch"
805 depends on CPU_V7
806 help
807 This option enables the workaround for the 430973 Cortex-A8
808 r1p* erratum. If a code sequence containing an ARM/Thumb
809 interworking branch is replaced with another code sequence at the
810 same virtual address, whether due to self-modifying code or virtual
811 to physical address re-mapping, Cortex-A8 does not recover from the
812 stale interworking branch prediction. This results in Cortex-A8
813 executing the new code sequence in the incorrect ARM or Thumb state.
814 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
815 and also flushes the branch target cache at every context switch.
816 Note that setting specific bits in the ACTLR register may not be
817 available in non-secure mode.
818
819 config ARM_ERRATA_458693
820 bool "ARM errata: Processor deadlock when a false hazard is created"
821 depends on CPU_V7
822 depends on !ARCH_MULTIPLATFORM
823 help
824 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
825 erratum. For very specific sequences of memory operations, it is
826 possible for a hazard condition intended for a cache line to instead
827 be incorrectly associated with a different cache line. This false
828 hazard might then cause a processor deadlock. The workaround enables
829 the L1 caching of the NEON accesses and disables the PLD instruction
830 in the ACTLR register. Note that setting specific bits in the ACTLR
831 register may not be available in non-secure mode.
832
833 config ARM_ERRATA_460075
834 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
835 depends on CPU_V7
836 depends on !ARCH_MULTIPLATFORM
837 help
838 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
839 erratum. Any asynchronous access to the L2 cache may encounter a
840 situation in which recent store transactions to the L2 cache are lost
841 and overwritten with stale memory contents from external memory. The
842 workaround disables the write-allocate mode for the L2 cache via the
843 ACTLR register. Note that setting specific bits in the ACTLR register
844 may not be available in non-secure mode.
845
846 config ARM_ERRATA_742230
847 bool "ARM errata: DMB operation may be faulty"
848 depends on CPU_V7 && SMP
849 depends on !ARCH_MULTIPLATFORM
850 help
851 This option enables the workaround for the 742230 Cortex-A9
852 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
853 between two write operations may not ensure the correct visibility
854 ordering of the two writes. This workaround sets a specific bit in
855 the diagnostic register of the Cortex-A9 which causes the DMB
856 instruction to behave as a DSB, ensuring the correct behaviour of
857 the two writes.
858
859 config ARM_ERRATA_742231
860 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
861 depends on CPU_V7 && SMP
862 depends on !ARCH_MULTIPLATFORM
863 help
864 This option enables the workaround for the 742231 Cortex-A9
865 (r2p0..r2p2) erratum. Under certain conditions, specific to the
866 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
867 accessing some data located in the same cache line, may get corrupted
868 data due to bad handling of the address hazard when the line gets
869 replaced from one of the CPUs at the same time as another CPU is
870 accessing it. This workaround sets specific bits in the diagnostic
871 register of the Cortex-A9 which reduces the linefill issuing
872 capabilities of the processor.
873
874 config ARM_ERRATA_643719
875 bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
876 depends on CPU_V7 && SMP
877 default y
878 help
879 This option enables the workaround for the 643719 Cortex-A9 (prior to
880 r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
881 register returns zero when it should return one. The workaround
882 corrects this value, ensuring cache maintenance operations which use
883 it behave as intended and avoiding data corruption.
884
885 config ARM_ERRATA_720789
886 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
887 depends on CPU_V7
888 help
889 This option enables the workaround for the 720789 Cortex-A9 (prior to
890 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
891 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
892 As a consequence of this erratum, some TLB entries which should be
893 invalidated are not, resulting in an incoherency in the system page
894 tables. The workaround changes the TLB flushing routines to invalidate
895 entries regardless of the ASID.
896
897 config ARM_ERRATA_743622
898 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
899 depends on CPU_V7
900 depends on !ARCH_MULTIPLATFORM
901 help
902 This option enables the workaround for the 743622 Cortex-A9
903 (r2p*) erratum. Under very rare conditions, a faulty
904 optimisation in the Cortex-A9 Store Buffer may lead to data
905 corruption. This workaround sets a specific bit in the diagnostic
906 register of the Cortex-A9 which disables the Store Buffer
907 optimisation, preventing the defect from occurring. This has no
908 visible impact on the overall performance or power consumption of the
909 processor.
910
911 config ARM_ERRATA_751472
912 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
913 depends on CPU_V7
914 depends on !ARCH_MULTIPLATFORM
915 help
916 This option enables the workaround for the 751472 Cortex-A9 (prior
917 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
918 completion of a following broadcasted operation if the second
919 operation is received by a CPU before the ICIALLUIS has completed,
920 potentially leading to corrupted entries in the cache or TLB.
921
922 config ARM_ERRATA_754322
923 bool "ARM errata: possible faulty MMU translations following an ASID switch"
924 depends on CPU_V7
925 help
926 This option enables the workaround for the 754322 Cortex-A9 (r2p*,
927 r3p*) erratum. A speculative memory access may cause a page table walk
928 which starts prior to an ASID switch but completes afterwards. This
929 can populate the micro-TLB with a stale entry which may be hit with
930 the new ASID. This workaround places two dsb instructions in the mm
931 switching code so that no page table walks can cross the ASID switch.
932
933 config ARM_ERRATA_754327
934 bool "ARM errata: no automatic Store Buffer drain"
935 depends on CPU_V7 && SMP
936 help
937 This option enables the workaround for the 754327 Cortex-A9 (prior to
938 r2p0) erratum. The Store Buffer does not have any automatic draining
939 mechanism and therefore a livelock may occur if an external agent
940 continuously polls a memory location waiting to observe an update.
941 This workaround defines cpu_relax() as smp_mb(), preventing correctly
942 written polling loops from denying visibility of updates to memory.
943
944 config ARM_ERRATA_364296
945 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
946 depends on CPU_V6
947 help
948 This options enables the workaround for the 364296 ARM1136
949 r0p2 erratum (possible cache data corruption with
950 hit-under-miss enabled). It sets the undocumented bit 31 in
951 the auxiliary control register and the FI bit in the control
952 register, thus disabling hit-under-miss without putting the
953 processor into full low interrupt latency mode. ARM11MPCore
954 is not affected.
955
956 config ARM_ERRATA_764369
957 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
958 depends on CPU_V7 && SMP
959 help
960 This option enables the workaround for erratum 764369
961 affecting Cortex-A9 MPCore with two or more processors (all
962 current revisions). Under certain timing circumstances, a data
963 cache line maintenance operation by MVA targeting an Inner
964 Shareable memory region may fail to proceed up to either the
965 Point of Coherency or to the Point of Unification of the
966 system. This workaround adds a DSB instruction before the
967 relevant cache maintenance functions and sets a specific bit
968 in the diagnostic control register of the SCU.
969
970 config ARM_ERRATA_775420
971 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
972 depends on CPU_V7
973 help
974 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
975 r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
976 operation aborts with MMU exception, it might cause the processor
977 to deadlock. This workaround puts DSB before executing ISB if
978 an abort may occur on cache maintenance.
979
980 config ARM_ERRATA_798181
981 bool "ARM errata: TLBI/DSB failure on Cortex-A15"
982 depends on CPU_V7 && SMP
983 help
984 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
985 adequately shooting down all use of the old entries. This
986 option enables the Linux kernel workaround for this erratum
987 which sends an IPI to the CPUs that are running the same ASID
988 as the one being invalidated.
989
990 config ARM_ERRATA_773022
991 bool "ARM errata: incorrect instructions may be executed from loop buffer"
992 depends on CPU_V7
993 help
994 This option enables the workaround for the 773022 Cortex-A15
995 (up to r0p4) erratum. In certain rare sequences of code, the
996 loop buffer may deliver incorrect instructions. This
997 workaround disables the loop buffer to avoid the erratum.
998
999 config ARM_ERRATA_818325_852422
1000 bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
1001 depends on CPU_V7
1002 help
1003 This option enables the workaround for:
1004 - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
1005 instruction might deadlock. Fixed in r0p1.
1006 - Cortex-A12 852422: Execution of a sequence of instructions might
1007 lead to either a data corruption or a CPU deadlock. Not fixed in
1008 any Cortex-A12 cores yet.
1009 This workaround for all both errata involves setting bit[12] of the
1010 Feature Register. This bit disables an optimisation applied to a
1011 sequence of 2 instructions that use opposing condition codes.
1012
1013 config ARM_ERRATA_821420
1014 bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
1015 depends on CPU_V7
1016 help
1017 This option enables the workaround for the 821420 Cortex-A12
1018 (all revs) erratum. In very rare timing conditions, a sequence
1019 of VMOV to Core registers instructions, for which the second
1020 one is in the shadow of a branch or abort, can lead to a
1021 deadlock when the VMOV instructions are issued out-of-order.
1022
1023 config ARM_ERRATA_825619
1024 bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
1025 depends on CPU_V7
1026 help
1027 This option enables the workaround for the 825619 Cortex-A12
1028 (all revs) erratum. Within rare timing constraints, executing a
1029 DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
1030 and Device/Strongly-Ordered loads and stores might cause deadlock
1031
1032 config ARM_ERRATA_857271
1033 bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
1034 depends on CPU_V7
1035 help
1036 This option enables the workaround for the 857271 Cortex-A12
1037 (all revs) erratum. Under very rare timing conditions, the CPU might
1038 hang. The workaround is expected to have a < 1% performance impact.
1039
1040 config ARM_ERRATA_852421
1041 bool "ARM errata: A17: DMB ST might fail to create order between stores"
1042 depends on CPU_V7
1043 help
1044 This option enables the workaround for the 852421 Cortex-A17
1045 (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
1046 execution of a DMB ST instruction might fail to properly order
1047 stores from GroupA and stores from GroupB.
1048
1049 config ARM_ERRATA_852423
1050 bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
1051 depends on CPU_V7
1052 help
1053 This option enables the workaround for:
1054 - Cortex-A17 852423: Execution of a sequence of instructions might
1055 lead to either a data corruption or a CPU deadlock. Not fixed in
1056 any Cortex-A17 cores yet.
1057 This is identical to Cortex-A12 erratum 852422. It is a separate
1058 config option from the A12 erratum due to the way errata are checked
1059 for and handled.
1060
1061 config ARM_ERRATA_857272
1062 bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
1063 depends on CPU_V7
1064 help
1065 This option enables the workaround for the 857272 Cortex-A17 erratum.
1066 This erratum is not known to be fixed in any A17 revision.
1067 This is identical to Cortex-A12 erratum 857271. It is a separate
1068 config option from the A12 erratum due to the way errata are checked
1069 for and handled.
1070
1071 endmenu
1072
1073 source "arch/arm/common/Kconfig"
1074
1075 menu "Bus support"
1076
1077 config ISA
1078 bool
1079 help
1080 Find out whether you have ISA slots on your motherboard. ISA is the
1081 name of a bus system, i.e. the way the CPU talks to the other stuff
1082 inside your box. Other bus systems are PCI, EISA, MicroChannel
1083 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1084 newer boards don't support it. If you have ISA, say Y, otherwise N.
1085
1086 # Select ISA DMA controller support
1087 config ISA_DMA
1088 bool
1089 select ISA_DMA_API
1090
1091 # Select ISA DMA interface
1092 config ISA_DMA_API
1093 bool
1094
1095 config PCI_NANOENGINE
1096 bool "BSE nanoEngine PCI support"
1097 depends on SA1100_NANOENGINE
1098 help
1099 Enable PCI on the BSE nanoEngine board.
1100
1101 config ARM_ERRATA_814220
1102 bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
1103 depends on CPU_V7
1104 help
1105 The v7 ARM states that all cache and branch predictor maintenance
1106 operations that do not specify an address execute, relative to
1107 each other, in program order.
1108 However, because of this erratum, an L2 set/way cache maintenance
1109 operation can overtake an L1 set/way cache maintenance operation.
1110 This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
1111 r0p4, r0p5.
1112
1113 endmenu
1114
1115 menu "Kernel Features"
1116
1117 config HAVE_SMP
1118 bool
1119 help
1120 This option should be selected by machines which have an SMP-
1121 capable CPU.
1122
1123 The only effect of this option is to make the SMP-related
1124 options available to the user for configuration.
1125
1126 config SMP
1127 bool "Symmetric Multi-Processing"
1128 depends on CPU_V6K || CPU_V7
1129 depends on HAVE_SMP
1130 depends on MMU || ARM_MPU
1131 select IRQ_WORK
1132 help
1133 This enables support for systems with more than one CPU. If you have
1134 a system with only one CPU, say N. If you have a system with more
1135 than one CPU, say Y.
1136
1137 If you say N here, the kernel will run on uni- and multiprocessor
1138 machines, but will use only one CPU of a multiprocessor machine. If
1139 you say Y here, the kernel will run on many, but not all,
1140 uniprocessor machines. On a uniprocessor machine, the kernel
1141 will run faster if you say N here.
1142
1143 See also <file:Documentation/x86/i386/IO-APIC.rst>,
1144 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
1145 <http://tldp.org/HOWTO/SMP-HOWTO.html>.
1146
1147 If you don't know what to do here, say N.
1148
1149 config SMP_ON_UP
1150 bool "Allow booting SMP kernel on uniprocessor systems"
1151 depends on SMP && !XIP_KERNEL && MMU
1152 default y
1153 help
1154 SMP kernels contain instructions which fail on non-SMP processors.
1155 Enabling this option allows the kernel to modify itself to make
1156 these instructions safe. Disabling it allows about 1K of space
1157 savings.
1158
1159 If you don't know what to do here, say Y.
1160
1161 config ARM_CPU_TOPOLOGY
1162 bool "Support cpu topology definition"
1163 depends on SMP && CPU_V7
1164 default y
1165 help
1166 Support ARM cpu topology definition. The MPIDR register defines
1167 affinity between processors which is then used to describe the cpu
1168 topology of an ARM System.
1169
1170 config SCHED_MC
1171 bool "Multi-core scheduler support"
1172 depends on ARM_CPU_TOPOLOGY
1173 help
1174 Multi-core scheduler support improves the CPU scheduler's decision
1175 making when dealing with multi-core CPU chips at a cost of slightly
1176 increased overhead in some places. If unsure say N here.
1177
1178 config SCHED_SMT
1179 bool "SMT scheduler support"
1180 depends on ARM_CPU_TOPOLOGY
1181 help
1182 Improves the CPU scheduler's decision making when dealing with
1183 MultiThreading at a cost of slightly increased overhead in some
1184 places. If unsure say N here.
1185
1186 config HAVE_ARM_SCU
1187 bool
1188 help
1189 This option enables support for the ARM snoop control unit
1190
1191 config HAVE_ARM_ARCH_TIMER
1192 bool "Architected timer support"
1193 depends on CPU_V7
1194 select ARM_ARCH_TIMER
1195 help
1196 This option enables support for the ARM architected timer
1197
1198 config HAVE_ARM_TWD
1199 bool
1200 help
1201 This options enables support for the ARM timer and watchdog unit
1202
1203 config MCPM
1204 bool "Multi-Cluster Power Management"
1205 depends on CPU_V7 && SMP
1206 help
1207 This option provides the common power management infrastructure
1208 for (multi-)cluster based systems, such as big.LITTLE based
1209 systems.
1210
1211 config MCPM_QUAD_CLUSTER
1212 bool
1213 depends on MCPM
1214 help
1215 To avoid wasting resources unnecessarily, MCPM only supports up
1216 to 2 clusters by default.
1217 Platforms with 3 or 4 clusters that use MCPM must select this
1218 option to allow the additional clusters to be managed.
1219
1220 config BIG_LITTLE
1221 bool "big.LITTLE support (Experimental)"
1222 depends on CPU_V7 && SMP
1223 select MCPM
1224 help
1225 This option enables support selections for the big.LITTLE
1226 system architecture.
1227
1228 config BL_SWITCHER
1229 bool "big.LITTLE switcher support"
1230 depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
1231 select CPU_PM
1232 help
1233 The big.LITTLE "switcher" provides the core functionality to
1234 transparently handle transition between a cluster of A15's
1235 and a cluster of A7's in a big.LITTLE system.
1236
1237 config BL_SWITCHER_DUMMY_IF
1238 tristate "Simple big.LITTLE switcher user interface"
1239 depends on BL_SWITCHER && DEBUG_KERNEL
1240 help
1241 This is a simple and dummy char dev interface to control
1242 the big.LITTLE switcher core code. It is meant for
1243 debugging purposes only.
1244
1245 choice
1246 prompt "Memory split"
1247 depends on MMU
1248 default VMSPLIT_3G
1249 help
1250 Select the desired split between kernel and user memory.
1251
1252 If you are not absolutely sure what you are doing, leave this
1253 option alone!
1254
1255 config VMSPLIT_3G
1256 bool "3G/1G user/kernel split"
1257 config VMSPLIT_3G_OPT
1258 depends on !ARM_LPAE
1259 bool "3G/1G user/kernel split (for full 1G low memory)"
1260 config VMSPLIT_2G
1261 bool "2G/2G user/kernel split"
1262 config VMSPLIT_1G
1263 bool "1G/3G user/kernel split"
1264 endchoice
1265
1266 config PAGE_OFFSET
1267 hex
1268 default PHYS_OFFSET if !MMU
1269 default 0x40000000 if VMSPLIT_1G
1270 default 0x80000000 if VMSPLIT_2G
1271 default 0xB0000000 if VMSPLIT_3G_OPT
1272 default 0xC0000000
1273
1274 config KASAN_SHADOW_OFFSET
1275 hex
1276 depends on KASAN
1277 default 0x1f000000 if PAGE_OFFSET=0x40000000
1278 default 0x5f000000 if PAGE_OFFSET=0x80000000
1279 default 0x9f000000 if PAGE_OFFSET=0xC0000000
1280 default 0x8f000000 if PAGE_OFFSET=0xB0000000
1281 default 0xffffffff
1282
1283 config NR_CPUS
1284 int "Maximum number of CPUs (2-32)"
1285 range 2 16 if DEBUG_KMAP_LOCAL
1286 range 2 32 if !DEBUG_KMAP_LOCAL
1287 depends on SMP
1288 default "4"
1289 help
1290 The maximum number of CPUs that the kernel can support.
1291 Up to 32 CPUs can be supported, or up to 16 if kmap_local()
1292 debugging is enabled, which uses half of the per-CPU fixmap
1293 slots as guard regions.
1294
1295 config HOTPLUG_CPU
1296 bool "Support for hot-pluggable CPUs"
1297 depends on SMP
1298 select GENERIC_IRQ_MIGRATION
1299 help
1300 Say Y here to experiment with turning CPUs off and on. CPUs
1301 can be controlled through /sys/devices/system/cpu.
1302
1303 config ARM_PSCI
1304 bool "Support for the ARM Power State Coordination Interface (PSCI)"
1305 depends on HAVE_ARM_SMCCC
1306 select ARM_PSCI_FW
1307 help
1308 Say Y here if you want Linux to communicate with system firmware
1309 implementing the PSCI specification for CPU-centric power
1310 management operations described in ARM document number ARM DEN
1311 0022A ("Power State Coordination Interface System Software on
1312 ARM processors").
1313
1314 # The GPIO number here must be sorted by descending number. In case of
1315 # a multiplatform kernel, we just want the highest value required by the
1316 # selected platforms.
1317 config ARCH_NR_GPIO
1318 int
1319 default 2048 if ARCH_INTEL_SOCFPGA
1320 default 1024 if ARCH_BRCMSTB || ARCH_RENESAS || ARCH_TEGRA || \
1321 ARCH_ZYNQ || ARCH_ASPEED
1322 default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \
1323 SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210
1324 default 416 if ARCH_SUNXI
1325 default 392 if ARCH_U8500
1326 default 352 if ARCH_VT8500
1327 default 288 if ARCH_ROCKCHIP
1328 default 264 if MACH_H4700
1329 default 0
1330 help
1331 Maximum number of GPIOs in the system.
1332
1333 If unsure, leave the default value.
1334
1335 config HZ_FIXED
1336 int
1337 default 128 if SOC_AT91RM9200
1338 default 0
1339
1340 choice
1341 depends on HZ_FIXED = 0
1342 prompt "Timer frequency"
1343
1344 config HZ_100
1345 bool "100 Hz"
1346
1347 config HZ_200
1348 bool "200 Hz"
1349
1350 config HZ_250
1351 bool "250 Hz"
1352
1353 config HZ_300
1354 bool "300 Hz"
1355
1356 config HZ_500
1357 bool "500 Hz"
1358
1359 config HZ_1000
1360 bool "1000 Hz"
1361
1362 endchoice
1363
1364 config HZ
1365 int
1366 default HZ_FIXED if HZ_FIXED != 0
1367 default 100 if HZ_100
1368 default 200 if HZ_200
1369 default 250 if HZ_250
1370 default 300 if HZ_300
1371 default 500 if HZ_500
1372 default 1000
1373
1374 config SCHED_HRTICK
1375 def_bool HIGH_RES_TIMERS
1376
1377 config THUMB2_KERNEL
1378 bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1379 depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1380 default y if CPU_THUMBONLY
1381 select ARM_UNWIND
1382 help
1383 By enabling this option, the kernel will be compiled in
1384 Thumb-2 mode.
1385
1386 If unsure, say N.
1387
1388 config ARM_PATCH_IDIV
1389 bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
1390 depends on CPU_32v7 && !XIP_KERNEL
1391 default y
1392 help
1393 The ARM compiler inserts calls to __aeabi_idiv() and
1394 __aeabi_uidiv() when it needs to perform division on signed
1395 and unsigned integers. Some v7 CPUs have support for the sdiv
1396 and udiv instructions that can be used to implement those
1397 functions.
1398
1399 Enabling this option allows the kernel to modify itself to
1400 replace the first two instructions of these library functions
1401 with the sdiv or udiv plus "bx lr" instructions when the CPU
1402 it is running on supports them. Typically this will be faster
1403 and less power intensive than running the original library
1404 code to do integer division.
1405
1406 config AEABI
1407 bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1408 !CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1409 default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
1410 help
1411 This option allows for the kernel to be compiled using the latest
1412 ARM ABI (aka EABI). This is only useful if you are using a user
1413 space environment that is also compiled with EABI.
1414
1415 Since there are major incompatibilities between the legacy ABI and
1416 EABI, especially with regard to structure member alignment, this
1417 option also changes the kernel syscall calling convention to
1418 disambiguate both ABIs and allow for backward compatibility support
1419 (selected with CONFIG_OABI_COMPAT).
1420
1421 To use this you need GCC version 4.0.0 or later.
1422
1423 config OABI_COMPAT
1424 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1425 depends on AEABI && !THUMB2_KERNEL
1426 help
1427 This option preserves the old syscall interface along with the
1428 new (ARM EABI) one. It also provides a compatibility layer to
1429 intercept syscalls that have structure arguments which layout
1430 in memory differs between the legacy ABI and the new ARM EABI
1431 (only for non "thumb" binaries). This option adds a tiny
1432 overhead to all syscalls and produces a slightly larger kernel.
1433
1434 The seccomp filter system will not be available when this is
1435 selected, since there is no way yet to sensibly distinguish
1436 between calling conventions during filtering.
1437
1438 If you know you'll be using only pure EABI user space then you
1439 can say N here. If this option is not selected and you attempt
1440 to execute a legacy ABI binary then the result will be
1441 UNPREDICTABLE (in fact it can be predicted that it won't work
1442 at all). If in doubt say N.
1443
1444 config ARCH_SELECT_MEMORY_MODEL
1445 bool
1446
1447 config ARCH_FLATMEM_ENABLE
1448 bool
1449
1450 config ARCH_SPARSEMEM_ENABLE
1451 bool
1452 select SPARSEMEM_STATIC if SPARSEMEM
1453
1454 config HIGHMEM
1455 bool "High Memory Support"
1456 depends on MMU
1457 select KMAP_LOCAL
1458 help
1459 The address space of ARM processors is only 4 Gigabytes large
1460 and it has to accommodate user address space, kernel address
1461 space as well as some memory mapped IO. That means that, if you
1462 have a large amount of physical memory and/or IO, not all of the
1463 memory can be "permanently mapped" by the kernel. The physical
1464 memory that is not permanently mapped is called "high memory".
1465
1466 Depending on the selected kernel/user memory split, minimum
1467 vmalloc space and actual amount of RAM, you may not need this
1468 option which should result in a slightly faster kernel.
1469
1470 If unsure, say n.
1471
1472 config HIGHPTE
1473 bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1474 depends on HIGHMEM
1475 default y
1476 help
1477 The VM uses one page of physical memory for each page table.
1478 For systems with a lot of processes, this can use a lot of
1479 precious low memory, eventually leading to low memory being
1480 consumed by page tables. Setting this option will allow
1481 user-space 2nd level page tables to reside in high memory.
1482
1483 config CPU_SW_DOMAIN_PAN
1484 bool "Enable use of CPU domains to implement privileged no-access"
1485 depends on MMU && !ARM_LPAE
1486 default y
1487 help
1488 Increase kernel security by ensuring that normal kernel accesses
1489 are unable to access userspace addresses. This can help prevent
1490 use-after-free bugs becoming an exploitable privilege escalation
1491 by ensuring that magic values (such as LIST_POISON) will always
1492 fault when dereferenced.
1493
1494 CPUs with low-vector mappings use a best-efforts implementation.
1495 Their lower 1MB needs to remain accessible for the vectors, but
1496 the remainder of userspace will become appropriately inaccessible.
1497
1498 config HW_PERF_EVENTS
1499 def_bool y
1500 depends on ARM_PMU
1501
1502 config ARCH_WANT_GENERAL_HUGETLB
1503 def_bool y
1504
1505 config ARM_MODULE_PLTS
1506 bool "Use PLTs to allow module memory to spill over into vmalloc area"
1507 depends on MODULES
1508 default y
1509 help
1510 Allocate PLTs when loading modules so that jumps and calls whose
1511 targets are too far away for their relative offsets to be encoded
1512 in the instructions themselves can be bounced via veneers in the
1513 module's PLT. This allows modules to be allocated in the generic
1514 vmalloc area after the dedicated module memory area has been
1515 exhausted. The modules will use slightly more memory, but after
1516 rounding up to page size, the actual memory footprint is usually
1517 the same.
1518
1519 Disabling this is usually safe for small single-platform
1520 configurations. If unsure, say y.
1521
1522 config FORCE_MAX_ZONEORDER
1523 int "Maximum zone order"
1524 default "12" if SOC_AM33XX
1525 default "9" if SA1111
1526 default "11"
1527 help
1528 The kernel memory allocator divides physically contiguous memory
1529 blocks into "zones", where each zone is a power of two number of
1530 pages. This option selects the largest power of two that the kernel
1531 keeps in the memory allocator. If you need to allocate very large
1532 blocks of physically contiguous memory, then you may need to
1533 increase this value.
1534
1535 This config option is actually maximum order plus one. For example,
1536 a value of 11 means that the largest free memory block is 2^10 pages.
1537
1538 config ALIGNMENT_TRAP
1539 def_bool CPU_CP15_MMU
1540 select HAVE_PROC_CPU if PROC_FS
1541 help
1542 ARM processors cannot fetch/store information which is not
1543 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1544 address divisible by 4. On 32-bit ARM processors, these non-aligned
1545 fetch/store instructions will be emulated in software if you say
1546 here, which has a severe performance impact. This is necessary for
1547 correct operation of some network protocols. With an IP-only
1548 configuration it is safe to say N, otherwise say Y.
1549
1550 config UACCESS_WITH_MEMCPY
1551 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1552 depends on MMU
1553 default y if CPU_FEROCEON
1554 help
1555 Implement faster copy_to_user and clear_user methods for CPU
1556 cores where a 8-word STM instruction give significantly higher
1557 memory write throughput than a sequence of individual 32bit stores.
1558
1559 A possible side effect is a slight increase in scheduling latency
1560 between threads sharing the same address space if they invoke
1561 such copy operations with large buffers.
1562
1563 However, if the CPU data cache is using a write-allocate mode,
1564 this option is unlikely to provide any performance gain.
1565
1566 config PARAVIRT
1567 bool "Enable paravirtualization code"
1568 help
1569 This changes the kernel so it can modify itself when it is run
1570 under a hypervisor, potentially improving performance significantly
1571 over full virtualization.
1572
1573 config PARAVIRT_TIME_ACCOUNTING
1574 bool "Paravirtual steal time accounting"
1575 select PARAVIRT
1576 help
1577 Select this option to enable fine granularity task steal time
1578 accounting. Time spent executing other tasks in parallel with
1579 the current vCPU is discounted from the vCPU power. To account for
1580 that, there can be a small performance impact.
1581
1582 If in doubt, say N here.
1583
1584 config XEN_DOM0
1585 def_bool y
1586 depends on XEN
1587
1588 config XEN
1589 bool "Xen guest support on ARM"
1590 depends on ARM && AEABI && OF
1591 depends on CPU_V7 && !CPU_V6
1592 depends on !GENERIC_ATOMIC64
1593 depends on MMU
1594 select ARCH_DMA_ADDR_T_64BIT
1595 select ARM_PSCI
1596 select SWIOTLB
1597 select SWIOTLB_XEN
1598 select PARAVIRT
1599 help
1600 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1601
1602 config STACKPROTECTOR_PER_TASK
1603 bool "Use a unique stack canary value for each task"
1604 depends on GCC_PLUGINS && STACKPROTECTOR && SMP && !XIP_DEFLATED_DATA
1605 select GCC_PLUGIN_ARM_SSP_PER_TASK
1606 default y
1607 help
1608 Due to the fact that GCC uses an ordinary symbol reference from
1609 which to load the value of the stack canary, this value can only
1610 change at reboot time on SMP systems, and all tasks running in the
1611 kernel's address space are forced to use the same canary value for
1612 the entire duration that the system is up.
1613
1614 Enable this option to switch to a different method that uses a
1615 different canary value for each task.
1616
1617 endmenu
1618
1619 menu "Boot options"
1620
1621 config USE_OF
1622 bool "Flattened Device Tree support"
1623 select IRQ_DOMAIN
1624 select OF
1625 help
1626 Include support for flattened device tree machine descriptions.
1627
1628 config ATAGS
1629 bool "Support for the traditional ATAGS boot data passing" if USE_OF
1630 default y
1631 help
1632 This is the traditional way of passing data to the kernel at boot
1633 time. If you are solely relying on the flattened device tree (or
1634 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1635 to remove ATAGS support from your kernel binary. If unsure,
1636 leave this to y.
1637
1638 config DEPRECATED_PARAM_STRUCT
1639 bool "Provide old way to pass kernel parameters"
1640 depends on ATAGS
1641 help
1642 This was deprecated in 2001 and announced to live on for 5 years.
1643 Some old boot loaders still use this way.
1644
1645 # Compressed boot loader in ROM. Yes, we really want to ask about
1646 # TEXT and BSS so we preserve their values in the config files.
1647 config ZBOOT_ROM_TEXT
1648 hex "Compressed ROM boot loader base address"
1649 default 0x0
1650 help
1651 The physical address at which the ROM-able zImage is to be
1652 placed in the target. Platforms which normally make use of
1653 ROM-able zImage formats normally set this to a suitable
1654 value in their defconfig file.
1655
1656 If ZBOOT_ROM is not enabled, this has no effect.
1657
1658 config ZBOOT_ROM_BSS
1659 hex "Compressed ROM boot loader BSS address"
1660 default 0x0
1661 help
1662 The base address of an area of read/write memory in the target
1663 for the ROM-able zImage which must be available while the
1664 decompressor is running. It must be large enough to hold the
1665 entire decompressed kernel plus an additional 128 KiB.
1666 Platforms which normally make use of ROM-able zImage formats
1667 normally set this to a suitable value in their defconfig file.
1668
1669 If ZBOOT_ROM is not enabled, this has no effect.
1670
1671 config ZBOOT_ROM
1672 bool "Compressed boot loader in ROM/flash"
1673 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1674 depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1675 help
1676 Say Y here if you intend to execute your compressed kernel image
1677 (zImage) directly from ROM or flash. If unsure, say N.
1678
1679 config ARM_APPENDED_DTB
1680 bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1681 depends on OF
1682 help
1683 With this option, the boot code will look for a device tree binary
1684 (DTB) appended to zImage
1685 (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1686
1687 This is meant as a backward compatibility convenience for those
1688 systems with a bootloader that can't be upgraded to accommodate
1689 the documented boot protocol using a device tree.
1690
1691 Beware that there is very little in terms of protection against
1692 this option being confused by leftover garbage in memory that might
1693 look like a DTB header after a reboot if no actual DTB is appended
1694 to zImage. Do not leave this option active in a production kernel
1695 if you don't intend to always append a DTB. Proper passing of the
1696 location into r2 of a bootloader provided DTB is always preferable
1697 to this option.
1698
1699 config ARM_ATAG_DTB_COMPAT
1700 bool "Supplement the appended DTB with traditional ATAG information"
1701 depends on ARM_APPENDED_DTB
1702 help
1703 Some old bootloaders can't be updated to a DTB capable one, yet
1704 they provide ATAGs with memory configuration, the ramdisk address,
1705 the kernel cmdline string, etc. Such information is dynamically
1706 provided by the bootloader and can't always be stored in a static
1707 DTB. To allow a device tree enabled kernel to be used with such
1708 bootloaders, this option allows zImage to extract the information
1709 from the ATAG list and store it at run time into the appended DTB.
1710
1711 choice
1712 prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1713 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1714
1715 config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1716 bool "Use bootloader kernel arguments if available"
1717 help
1718 Uses the command-line options passed by the boot loader instead of
1719 the device tree bootargs property. If the boot loader doesn't provide
1720 any, the device tree bootargs property will be used.
1721
1722 config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1723 bool "Extend with bootloader kernel arguments"
1724 help
1725 The command-line arguments provided by the boot loader will be
1726 appended to the the device tree bootargs property.
1727
1728 endchoice
1729
1730 config CMDLINE
1731 string "Default kernel command string"
1732 default ""
1733 help
1734 On some architectures (e.g. CATS), there is currently no way
1735 for the boot loader to pass arguments to the kernel. For these
1736 architectures, you should supply some command-line options at build
1737 time by entering them here. As a minimum, you should specify the
1738 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1739
1740 choice
1741 prompt "Kernel command line type" if CMDLINE != ""
1742 default CMDLINE_FROM_BOOTLOADER
1743 depends on ATAGS
1744
1745 config CMDLINE_FROM_BOOTLOADER
1746 bool "Use bootloader kernel arguments if available"
1747 help
1748 Uses the command-line options passed by the boot loader. If
1749 the boot loader doesn't provide any, the default kernel command
1750 string provided in CMDLINE will be used.
1751
1752 config CMDLINE_EXTEND
1753 bool "Extend bootloader kernel arguments"
1754 help
1755 The command-line arguments provided by the boot loader will be
1756 appended to the default kernel command string.
1757
1758 config CMDLINE_FORCE
1759 bool "Always use the default kernel command string"
1760 help
1761 Always use the default kernel command string, even if the boot
1762 loader passes other arguments to the kernel.
1763 This is useful if you cannot or don't want to change the
1764 command-line options your boot loader passes to the kernel.
1765 endchoice
1766
1767 config XIP_KERNEL
1768 bool "Kernel Execute-In-Place from ROM"
1769 depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
1770 help
1771 Execute-In-Place allows the kernel to run from non-volatile storage
1772 directly addressable by the CPU, such as NOR flash. This saves RAM
1773 space since the text section of the kernel is not loaded from flash
1774 to RAM. Read-write sections, such as the data section and stack,
1775 are still copied to RAM. The XIP kernel is not compressed since
1776 it has to run directly from flash, so it will take more space to
1777 store it. The flash address used to link the kernel object files,
1778 and for storing it, is configuration dependent. Therefore, if you
1779 say Y here, you must know the proper physical address where to
1780 store the kernel image depending on your own flash memory usage.
1781
1782 Also note that the make target becomes "make xipImage" rather than
1783 "make zImage" or "make Image". The final kernel binary to put in
1784 ROM memory will be arch/arm/boot/xipImage.
1785
1786 If unsure, say N.
1787
1788 config XIP_PHYS_ADDR
1789 hex "XIP Kernel Physical Location"
1790 depends on XIP_KERNEL
1791 default "0x00080000"
1792 help
1793 This is the physical address in your flash memory the kernel will
1794 be linked for and stored to. This address is dependent on your
1795 own flash usage.
1796
1797 config XIP_DEFLATED_DATA
1798 bool "Store kernel .data section compressed in ROM"
1799 depends on XIP_KERNEL
1800 select ZLIB_INFLATE
1801 help
1802 Before the kernel is actually executed, its .data section has to be
1803 copied to RAM from ROM. This option allows for storing that data
1804 in compressed form and decompressed to RAM rather than merely being
1805 copied, saving some precious ROM space. A possible drawback is a
1806 slightly longer boot delay.
1807
1808 config KEXEC
1809 bool "Kexec system call (EXPERIMENTAL)"
1810 depends on (!SMP || PM_SLEEP_SMP)
1811 depends on MMU
1812 select KEXEC_CORE
1813 help
1814 kexec is a system call that implements the ability to shutdown your
1815 current kernel, and to start another kernel. It is like a reboot
1816 but it is independent of the system firmware. And like a reboot
1817 you can start any kernel with it, not just Linux.
1818
1819 It is an ongoing process to be certain the hardware in a machine
1820 is properly shutdown, so do not be surprised if this code does not
1821 initially work for you.
1822
1823 config ATAGS_PROC
1824 bool "Export atags in procfs"
1825 depends on ATAGS && KEXEC
1826 default y
1827 help
1828 Should the atags used to boot the kernel be exported in an "atags"
1829 file in procfs. Useful with kexec.
1830
1831 config CRASH_DUMP
1832 bool "Build kdump crash kernel (EXPERIMENTAL)"
1833 help
1834 Generate crash dump after being started by kexec. This should
1835 be normally only set in special crash dump kernels which are
1836 loaded in the main kernel with kexec-tools into a specially
1837 reserved region and then later executed after a crash by
1838 kdump/kexec. The crash dump kernel must be compiled to a
1839 memory address not used by the main kernel
1840
1841 For more details see Documentation/admin-guide/kdump/kdump.rst
1842
1843 config AUTO_ZRELADDR
1844 bool "Auto calculation of the decompressed kernel image address"
1845 help
1846 ZRELADDR is the physical address where the decompressed kernel
1847 image will be placed. If AUTO_ZRELADDR is selected, the address
1848 will be determined at run-time, either by masking the current IP
1849 with 0xf8000000, or, if invalid, from the DTB passed in r2.
1850 This assumes the zImage being placed in the first 128MB from
1851 start of memory.
1852
1853 config EFI_STUB
1854 bool
1855
1856 config EFI
1857 bool "UEFI runtime support"
1858 depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
1859 select UCS2_STRING
1860 select EFI_PARAMS_FROM_FDT
1861 select EFI_STUB
1862 select EFI_GENERIC_STUB
1863 select EFI_RUNTIME_WRAPPERS
1864 help
1865 This option provides support for runtime services provided
1866 by UEFI firmware (such as non-volatile variables, realtime
1867 clock, and platform reset). A UEFI stub is also provided to
1868 allow the kernel to be booted as an EFI application. This
1869 is only useful for kernels that may run on systems that have
1870 UEFI firmware.
1871
1872 config DMI
1873 bool "Enable support for SMBIOS (DMI) tables"
1874 depends on EFI
1875 default y
1876 help
1877 This enables SMBIOS/DMI feature for systems.
1878
1879 This option is only useful on systems that have UEFI firmware.
1880 However, even with this option, the resultant kernel should
1881 continue to boot on existing non-UEFI platforms.
1882
1883 NOTE: This does *NOT* enable or encourage the use of DMI quirks,
1884 i.e., the the practice of identifying the platform via DMI to
1885 decide whether certain workarounds for buggy hardware and/or
1886 firmware need to be enabled. This would require the DMI subsystem
1887 to be enabled much earlier than we do on ARM, which is non-trivial.
1888
1889 endmenu
1890
1891 menu "CPU Power Management"
1892
1893 source "drivers/cpufreq/Kconfig"
1894
1895 source "drivers/cpuidle/Kconfig"
1896
1897 endmenu
1898
1899 menu "Floating point emulation"
1900
1901 comment "At least one emulation must be selected"
1902
1903 config FPE_NWFPE
1904 bool "NWFPE math emulation"
1905 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
1906 help
1907 Say Y to include the NWFPE floating point emulator in the kernel.
1908 This is necessary to run most binaries. Linux does not currently
1909 support floating point hardware so you need to say Y here even if
1910 your machine has an FPA or floating point co-processor podule.
1911
1912 You may say N here if you are going to load the Acorn FPEmulator
1913 early in the bootup.
1914
1915 config FPE_NWFPE_XP
1916 bool "Support extended precision"
1917 depends on FPE_NWFPE
1918 help
1919 Say Y to include 80-bit support in the kernel floating-point
1920 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1921 Note that gcc does not generate 80-bit operations by default,
1922 so in most cases this option only enlarges the size of the
1923 floating point emulator without any good reason.
1924
1925 You almost surely want to say N here.
1926
1927 config FPE_FASTFPE
1928 bool "FastFPE math emulation (EXPERIMENTAL)"
1929 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
1930 help
1931 Say Y here to include the FAST floating point emulator in the kernel.
1932 This is an experimental much faster emulator which now also has full
1933 precision for the mantissa. It does not support any exceptions.
1934 It is very simple, and approximately 3-6 times faster than NWFPE.
1935
1936 It should be sufficient for most programs. It may be not suitable
1937 for scientific calculations, but you have to check this for yourself.
1938 If you do not feel you need a faster FP emulation you should better
1939 choose NWFPE.
1940
1941 config VFP
1942 bool "VFP-format floating point maths"
1943 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1944 help
1945 Say Y to include VFP support code in the kernel. This is needed
1946 if your hardware includes a VFP unit.
1947
1948 Please see <file:Documentation/arm/vfp/release-notes.rst> for
1949 release notes and additional status information.
1950
1951 Say N if your target does not have VFP hardware.
1952
1953 config VFPv3
1954 bool
1955 depends on VFP
1956 default y if CPU_V7
1957
1958 config NEON
1959 bool "Advanced SIMD (NEON) Extension support"
1960 depends on VFPv3 && CPU_V7
1961 help
1962 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1963 Extension.
1964
1965 config KERNEL_MODE_NEON
1966 bool "Support for NEON in kernel mode"
1967 depends on NEON && AEABI
1968 help
1969 Say Y to include support for NEON in kernel mode.
1970
1971 endmenu
1972
1973 menu "Power management options"
1974
1975 source "kernel/power/Kconfig"
1976
1977 config ARCH_SUSPEND_POSSIBLE
1978 depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
1979 CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
1980 def_bool y
1981
1982 config ARM_CPU_SUSPEND
1983 def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
1984 depends on ARCH_SUSPEND_POSSIBLE
1985
1986 config ARCH_HIBERNATION_POSSIBLE
1987 bool
1988 depends on MMU
1989 default y if ARCH_SUSPEND_POSSIBLE
1990
1991 endmenu
1992
1993 source "drivers/firmware/Kconfig"
1994
1995 if CRYPTO
1996 source "arch/arm/crypto/Kconfig"
1997 endif
1998
1999 source "arch/arm/Kconfig.assembler"