Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1# SPDX-License-Identifier: GPL-2.0
2config 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
22 select ARCH_HAS_SYNC_DMA_FOR_CPU if SWIOTLB
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_OPS
48 select DMA_REMAP if MMU
49 select EDAC_SUPPORT
50 select EDAC_ATOMIC_SCRUB
51 select GENERIC_ALLOCATOR
52 select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
53 select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
54 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
55 select GENERIC_IRQ_IPI if SMP
56 select GENERIC_CPU_AUTOPROBE
57 select GENERIC_EARLY_IOREMAP
58 select GENERIC_IDLE_POLL_SETUP
59 select GENERIC_IRQ_PROBE
60 select GENERIC_IRQ_SHOW
61 select GENERIC_IRQ_SHOW_LEVEL
62 select GENERIC_LIB_DEVMEM_IS_ALLOWED
63 select GENERIC_PCI_IOMAP
64 select GENERIC_SCHED_CLOCK
65 select GENERIC_SMP_IDLE_THREAD
66 select GENERIC_STRNCPY_FROM_USER
67 select GENERIC_STRNLEN_USER
68 select HANDLE_DOMAIN_IRQ
69 select HARDIRQS_SW_RESEND
70 select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
71 select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
72 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
73 select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
74 select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
75 select HAVE_ARCH_MMAP_RND_BITS if MMU
76 select HAVE_ARCH_PFN_VALID
77 select HAVE_ARCH_SECCOMP
78 select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT
79 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
80 select HAVE_ARCH_TRACEHOOK
81 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARM_LPAE
82 select HAVE_ARM_SMCCC if CPU_V7
83 select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
84 select HAVE_CONTEXT_TRACKING
85 select HAVE_C_RECORDMCOUNT
86 select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL
87 select HAVE_DMA_CONTIGUOUS if MMU
88 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
89 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
90 select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
91 select HAVE_EXIT_THREAD
92 select HAVE_FAST_GUP if ARM_LPAE
93 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
94 select HAVE_FUNCTION_GRAPH_TRACER if !THUMB2_KERNEL && !CC_IS_CLANG
95 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
96 select HAVE_GCC_PLUGINS
97 select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7)
98 select HAVE_IDE if PCI || ISA || PCMCIA
99 select HAVE_IRQ_TIME_ACCOUNTING
100 select HAVE_KERNEL_GZIP
101 select HAVE_KERNEL_LZ4
102 select HAVE_KERNEL_LZMA
103 select HAVE_KERNEL_LZO
104 select HAVE_KERNEL_XZ
105 select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
106 select HAVE_KRETPROBES if HAVE_KPROBES
107 select HAVE_MOD_ARCH_SPECIFIC
108 select HAVE_NMI
109 select HAVE_OPTPROBES if !THUMB2_KERNEL
110 select HAVE_PERF_EVENTS
111 select HAVE_PERF_REGS
112 select HAVE_PERF_USER_STACK_DUMP
113 select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
114 select HAVE_REGS_AND_STACK_ACCESS_API
115 select HAVE_RSEQ
116 select HAVE_STACKPROTECTOR
117 select HAVE_SYSCALL_TRACEPOINTS
118 select HAVE_UID16
119 select HAVE_VIRT_CPU_ACCOUNTING_GEN
120 select IRQ_FORCED_THREADING
121 select MODULES_USE_ELF_REL
122 select NEED_DMA_MAP_STATE
123 select OF_EARLY_FLATTREE if OF
124 select OLD_SIGACTION
125 select OLD_SIGSUSPEND3
126 select PCI_SYSCALL if PCI
127 select PERF_USE_VMALLOC
128 select RTC_LIB
129 select SET_FS
130 select SYS_SUPPORTS_APM_EMULATION
131 # Above selects are sorted alphabetically; please add new ones
132 # according to that. Thanks.
133 help
134 The ARM series is a line of low-power-consumption RISC chip designs
135 licensed by ARM Ltd and targeted at embedded applications and
136 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
137 manufactured, but legacy ARM-based PC hardware remains popular in
138 Europe. There is an ARM Linux project with a web page at
139 <http://www.arm.linux.org.uk/>.
140
141config ARM_HAS_SG_CHAIN
142 bool
143
144config ARM_DMA_USE_IOMMU
145 bool
146 select ARM_HAS_SG_CHAIN
147 select NEED_SG_DMA_LENGTH
148
149if ARM_DMA_USE_IOMMU
150
151config ARM_DMA_IOMMU_ALIGNMENT
152 int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
153 range 4 9
154 default 8
155 help
156 DMA mapping framework by default aligns all buffers to the smallest
157 PAGE_SIZE order which is greater than or equal to the requested buffer
158 size. This works well for buffers up to a few hundreds kilobytes, but
159 for larger buffers it just a waste of address space. Drivers which has
160 relatively small addressing window (like 64Mib) might run out of
161 virtual space with just a few allocations.
162
163 With this parameter you can specify the maximum PAGE_SIZE order for
164 DMA IOMMU buffers. Larger buffers will be aligned only to this
165 specified order. The order is expressed as a power of two multiplied
166 by the PAGE_SIZE.
167
168endif
169
170config SYS_SUPPORTS_APM_EMULATION
171 bool
172
173config HAVE_TCM
174 bool
175 select GENERIC_ALLOCATOR
176
177config HAVE_PROC_CPU
178 bool
179
180config NO_IOPORT_MAP
181 bool
182
183config SBUS
184 bool
185
186config STACKTRACE_SUPPORT
187 bool
188 default y
189
190config LOCKDEP_SUPPORT
191 bool
192 default y
193
194config TRACE_IRQFLAGS_SUPPORT
195 bool
196 default !CPU_V7M
197
198config ARCH_HAS_ILOG2_U32
199 bool
200
201config ARCH_HAS_ILOG2_U64
202 bool
203
204config ARCH_HAS_BANDGAP
205 bool
206
207config FIX_EARLYCON_MEM
208 def_bool y if MMU
209
210config GENERIC_HWEIGHT
211 bool
212 default y
213
214config GENERIC_CALIBRATE_DELAY
215 bool
216 default y
217
218config ARCH_MAY_HAVE_PC_FDC
219 bool
220
221config ARCH_SUPPORTS_UPROBES
222 def_bool y
223
224config ARCH_HAS_DMA_SET_COHERENT_MASK
225 bool
226
227config GENERIC_ISA_DMA
228 bool
229
230config FIQ
231 bool
232
233config NEED_RET_TO_USER
234 bool
235
236config ARCH_MTD_XIP
237 bool
238
239config ARM_PATCH_PHYS_VIRT
240 bool "Patch physical to virtual translations at runtime" if EMBEDDED
241 default y
242 depends on !XIP_KERNEL && MMU
243 help
244 Patch phys-to-virt and virt-to-phys translation functions at
245 boot and module load time according to the position of the
246 kernel in system memory.
247
248 This can only be used with non-XIP MMU kernels where the base
249 of physical memory is at a 2 MiB boundary.
250
251 Only disable this option if you know that you do not require
252 this feature (eg, building a kernel for a single machine) and
253 you need to shrink the kernel to the minimal size.
254
255config NEED_MACH_IO_H
256 bool
257 help
258 Select this when mach/io.h is required to provide special
259 definitions for this platform. The need for mach/io.h should
260 be avoided when possible.
261
262config NEED_MACH_MEMORY_H
263 bool
264 help
265 Select this when mach/memory.h is required to provide special
266 definitions for this platform. The need for mach/memory.h should
267 be avoided when possible.
268
269config PHYS_OFFSET
270 hex "Physical address of main memory" if MMU
271 depends on !ARM_PATCH_PHYS_VIRT
272 default DRAM_BASE if !MMU
273 default 0x00000000 if ARCH_FOOTBRIDGE
274 default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
275 default 0x20000000 if ARCH_S5PV210
276 default 0xc0000000 if ARCH_SA1100
277 help
278 Please provide the physical address corresponding to the
279 location of main memory in your system.
280
281config GENERIC_BUG
282 def_bool y
283 depends on BUG
284
285config PGTABLE_LEVELS
286 int
287 default 3 if ARM_LPAE
288 default 2
289
290menu "System Type"
291
292config MMU
293 bool "MMU-based Paged Memory Management Support"
294 default y
295 help
296 Select if you want MMU-based virtualised addressing space
297 support by paged memory management. If unsure, say 'Y'.
298
299config ARCH_MMAP_RND_BITS_MIN
300 default 8
301
302config ARCH_MMAP_RND_BITS_MAX
303 default 14 if PAGE_OFFSET=0x40000000
304 default 15 if PAGE_OFFSET=0x80000000
305 default 16
306
307#
308# The "ARM system type" choice list is ordered alphabetically by option
309# text. Please add new entries in the option alphabetic order.
310#
311choice
312 prompt "ARM system type"
313 default ARM_SINGLE_ARMV7M if !MMU
314 default ARCH_MULTIPLATFORM if MMU
315
316config ARCH_MULTIPLATFORM
317 bool "Allow multiple platforms to be selected"
318 depends on MMU
319 select ARCH_FLATMEM_ENABLE
320 select ARCH_SPARSEMEM_ENABLE
321 select ARCH_SELECT_MEMORY_MODEL
322 select ARM_HAS_SG_CHAIN
323 select ARM_PATCH_PHYS_VIRT
324 select AUTO_ZRELADDR
325 select TIMER_OF
326 select COMMON_CLK
327 select GENERIC_IRQ_MULTI_HANDLER
328 select HAVE_PCI
329 select PCI_DOMAINS_GENERIC if PCI
330 select SPARSE_IRQ
331 select USE_OF
332
333config ARM_SINGLE_ARMV7M
334 bool "ARMv7-M based platforms (Cortex-M0/M3/M4)"
335 depends on !MMU
336 select ARM_NVIC
337 select AUTO_ZRELADDR
338 select TIMER_OF
339 select COMMON_CLK
340 select CPU_V7M
341 select NO_IOPORT_MAP
342 select SPARSE_IRQ
343 select USE_OF
344
345config ARCH_EP93XX
346 bool "EP93xx-based"
347 select ARCH_SPARSEMEM_ENABLE
348 select ARM_AMBA
349 imply ARM_PATCH_PHYS_VIRT
350 select ARM_VIC
351 select GENERIC_IRQ_MULTI_HANDLER
352 select AUTO_ZRELADDR
353 select CLKSRC_MMIO
354 select CPU_ARM920T
355 select GPIOLIB
356 select HAVE_LEGACY_CLK
357 help
358 This enables support for the Cirrus EP93xx series of CPUs.
359
360config ARCH_FOOTBRIDGE
361 bool "FootBridge"
362 select CPU_SA110
363 select FOOTBRIDGE
364 select HAVE_IDE
365 select NEED_MACH_IO_H if !MMU
366 select NEED_MACH_MEMORY_H
367 help
368 Support for systems based on the DC21285 companion chip
369 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
370
371config ARCH_IOP32X
372 bool "IOP32x-based"
373 depends on MMU
374 select CPU_XSCALE
375 select GPIO_IOP
376 select GPIOLIB
377 select NEED_RET_TO_USER
378 select FORCE_PCI
379 select PLAT_IOP
380 help
381 Support for Intel's 80219 and IOP32X (XScale) family of
382 processors.
383
384config ARCH_IXP4XX
385 bool "IXP4xx-based"
386 depends on MMU
387 select ARCH_HAS_DMA_SET_COHERENT_MASK
388 select ARCH_SUPPORTS_BIG_ENDIAN
389 select CPU_XSCALE
390 select DMABOUNCE if PCI
391 select GENERIC_IRQ_MULTI_HANDLER
392 select GPIO_IXP4XX
393 select GPIOLIB
394 select HAVE_PCI
395 select IXP4XX_IRQ
396 select IXP4XX_TIMER
397 # With the new PCI driver this is not needed
398 select NEED_MACH_IO_H if PCI_IXP4XX_LEGACY
399 select USB_EHCI_BIG_ENDIAN_DESC
400 select USB_EHCI_BIG_ENDIAN_MMIO
401 help
402 Support for Intel's IXP4XX (XScale) family of processors.
403
404config ARCH_DOVE
405 bool "Marvell Dove"
406 select CPU_PJ4
407 select GENERIC_IRQ_MULTI_HANDLER
408 select GPIOLIB
409 select HAVE_PCI
410 select MVEBU_MBUS
411 select PINCTRL
412 select PINCTRL_DOVE
413 select PLAT_ORION_LEGACY
414 select SPARSE_IRQ
415 select PM_GENERIC_DOMAINS if PM
416 help
417 Support for the Marvell Dove SoC 88AP510
418
419config ARCH_PXA
420 bool "PXA2xx/PXA3xx-based"
421 depends on MMU
422 select ARCH_MTD_XIP
423 select ARM_CPU_SUSPEND if PM
424 select AUTO_ZRELADDR
425 select COMMON_CLK
426 select CLKSRC_PXA
427 select CLKSRC_MMIO
428 select TIMER_OF
429 select CPU_XSCALE if !CPU_XSC3
430 select GENERIC_IRQ_MULTI_HANDLER
431 select GPIO_PXA
432 select GPIOLIB
433 select HAVE_IDE
434 select IRQ_DOMAIN
435 select PLAT_PXA
436 select SPARSE_IRQ
437 help
438 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
439
440config ARCH_RPC
441 bool "RiscPC"
442 depends on MMU
443 select ARCH_ACORN
444 select ARCH_MAY_HAVE_PC_FDC
445 select ARCH_SPARSEMEM_ENABLE
446 select ARM_HAS_SG_CHAIN
447 select CPU_SA110
448 select FIQ
449 select HAVE_IDE
450 select HAVE_PATA_PLATFORM
451 select ISA_DMA_API
452 select LEGACY_TIMER_TICK
453 select NEED_MACH_IO_H
454 select NEED_MACH_MEMORY_H
455 select NO_IOPORT_MAP
456 help
457 On the Acorn Risc-PC, Linux can support the internal IDE disk and
458 CD-ROM interface, serial and parallel port, and the floppy drive.
459
460config ARCH_SA1100
461 bool "SA1100-based"
462 select ARCH_MTD_XIP
463 select ARCH_SPARSEMEM_ENABLE
464 select CLKSRC_MMIO
465 select CLKSRC_PXA
466 select TIMER_OF if OF
467 select COMMON_CLK
468 select CPU_FREQ
469 select CPU_SA1100
470 select GENERIC_IRQ_MULTI_HANDLER
471 select GPIOLIB
472 select HAVE_IDE
473 select IRQ_DOMAIN
474 select ISA
475 select NEED_MACH_MEMORY_H
476 select SPARSE_IRQ
477 help
478 Support for StrongARM 11x0 based boards.
479
480config ARCH_S3C24XX
481 bool "Samsung S3C24XX SoCs"
482 select ATAGS
483 select CLKSRC_SAMSUNG_PWM
484 select GPIO_SAMSUNG
485 select GPIOLIB
486 select GENERIC_IRQ_MULTI_HANDLER
487 select HAVE_S3C2410_I2C if I2C
488 select HAVE_S3C_RTC if RTC_CLASS
489 select NEED_MACH_IO_H
490 select S3C2410_WATCHDOG
491 select SAMSUNG_ATAGS
492 select USE_OF
493 select WATCHDOG
494 help
495 Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443
496 and S3C2450 SoCs based systems, such as the Simtec Electronics BAST
497 (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or the
498 Samsung SMDK2410 development board (and derivatives).
499
500config ARCH_OMAP1
501 bool "TI OMAP1"
502 depends on MMU
503 select ARCH_OMAP
504 select CLKSRC_MMIO
505 select GENERIC_IRQ_CHIP
506 select GENERIC_IRQ_MULTI_HANDLER
507 select GPIOLIB
508 select HAVE_IDE
509 select HAVE_LEGACY_CLK
510 select IRQ_DOMAIN
511 select NEED_MACH_IO_H if PCCARD
512 select NEED_MACH_MEMORY_H
513 select SPARSE_IRQ
514 help
515 Support for older TI OMAP1 (omap7xx, omap15xx or omap16xx)
516
517endchoice
518
519menu "Multiple platform selection"
520 depends on ARCH_MULTIPLATFORM
521
522comment "CPU Core family selection"
523
524config ARCH_MULTI_V4
525 bool "ARMv4 based platforms (FA526)"
526 depends on !ARCH_MULTI_V6_V7
527 select ARCH_MULTI_V4_V5
528 select CPU_FA526
529
530config ARCH_MULTI_V4T
531 bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
532 depends on !ARCH_MULTI_V6_V7
533 select ARCH_MULTI_V4_V5
534 select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
535 CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
536 CPU_ARM925T || CPU_ARM940T)
537
538config ARCH_MULTI_V5
539 bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
540 depends on !ARCH_MULTI_V6_V7
541 select ARCH_MULTI_V4_V5
542 select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
543 CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
544 CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
545
546config ARCH_MULTI_V4_V5
547 bool
548
549config ARCH_MULTI_V6
550 bool "ARMv6 based platforms (ARM11)"
551 select ARCH_MULTI_V6_V7
552 select CPU_V6K
553
554config ARCH_MULTI_V7
555 bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
556 default y
557 select ARCH_MULTI_V6_V7
558 select CPU_V7
559 select HAVE_SMP
560
561config ARCH_MULTI_V6_V7
562 bool
563 select MIGHT_HAVE_CACHE_L2X0
564
565config ARCH_MULTI_CPU_AUTO
566 def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
567 select ARCH_MULTI_V5
568
569endmenu
570
571config ARCH_VIRT
572 bool "Dummy Virtual Machine"
573 depends on ARCH_MULTI_V7
574 select ARM_AMBA
575 select ARM_GIC
576 select ARM_GIC_V2M if PCI
577 select ARM_GIC_V3
578 select ARM_GIC_V3_ITS if PCI
579 select ARM_PSCI
580 select HAVE_ARM_ARCH_TIMER
581 select ARCH_SUPPORTS_BIG_ENDIAN
582
583#
584# This is sorted alphabetically by mach-* pathname. However, plat-*
585# Kconfigs may be included either alphabetically (according to the
586# plat- suffix) or along side the corresponding mach-* source.
587#
588source "arch/arm/mach-actions/Kconfig"
589
590source "arch/arm/mach-alpine/Kconfig"
591
592source "arch/arm/mach-artpec/Kconfig"
593
594source "arch/arm/mach-asm9260/Kconfig"
595
596source "arch/arm/mach-aspeed/Kconfig"
597
598source "arch/arm/mach-at91/Kconfig"
599
600source "arch/arm/mach-axxia/Kconfig"
601
602source "arch/arm/mach-bcm/Kconfig"
603
604source "arch/arm/mach-berlin/Kconfig"
605
606source "arch/arm/mach-clps711x/Kconfig"
607
608source "arch/arm/mach-cns3xxx/Kconfig"
609
610source "arch/arm/mach-davinci/Kconfig"
611
612source "arch/arm/mach-digicolor/Kconfig"
613
614source "arch/arm/mach-dove/Kconfig"
615
616source "arch/arm/mach-ep93xx/Kconfig"
617
618source "arch/arm/mach-exynos/Kconfig"
619
620source "arch/arm/mach-footbridge/Kconfig"
621
622source "arch/arm/mach-gemini/Kconfig"
623
624source "arch/arm/mach-highbank/Kconfig"
625
626source "arch/arm/mach-hisi/Kconfig"
627
628source "arch/arm/mach-imx/Kconfig"
629
630source "arch/arm/mach-integrator/Kconfig"
631
632source "arch/arm/mach-iop32x/Kconfig"
633
634source "arch/arm/mach-ixp4xx/Kconfig"
635
636source "arch/arm/mach-keystone/Kconfig"
637
638source "arch/arm/mach-lpc32xx/Kconfig"
639
640source "arch/arm/mach-mediatek/Kconfig"
641
642source "arch/arm/mach-meson/Kconfig"
643
644source "arch/arm/mach-milbeaut/Kconfig"
645
646source "arch/arm/mach-mmp/Kconfig"
647
648source "arch/arm/mach-moxart/Kconfig"
649
650source "arch/arm/mach-mstar/Kconfig"
651
652source "arch/arm/mach-mv78xx0/Kconfig"
653
654source "arch/arm/mach-mvebu/Kconfig"
655
656source "arch/arm/mach-mxs/Kconfig"
657
658source "arch/arm/mach-nomadik/Kconfig"
659
660source "arch/arm/mach-npcm/Kconfig"
661
662source "arch/arm/mach-nspire/Kconfig"
663
664source "arch/arm/plat-omap/Kconfig"
665
666source "arch/arm/mach-omap1/Kconfig"
667
668source "arch/arm/mach-omap2/Kconfig"
669
670source "arch/arm/mach-orion5x/Kconfig"
671
672source "arch/arm/mach-oxnas/Kconfig"
673
674source "arch/arm/mach-pxa/Kconfig"
675source "arch/arm/plat-pxa/Kconfig"
676
677source "arch/arm/mach-qcom/Kconfig"
678
679source "arch/arm/mach-rda/Kconfig"
680
681source "arch/arm/mach-realtek/Kconfig"
682
683source "arch/arm/mach-realview/Kconfig"
684
685source "arch/arm/mach-rockchip/Kconfig"
686
687source "arch/arm/mach-s3c/Kconfig"
688
689source "arch/arm/mach-s5pv210/Kconfig"
690
691source "arch/arm/mach-sa1100/Kconfig"
692
693source "arch/arm/mach-shmobile/Kconfig"
694
695source "arch/arm/mach-socfpga/Kconfig"
696
697source "arch/arm/mach-spear/Kconfig"
698
699source "arch/arm/mach-sti/Kconfig"
700
701source "arch/arm/mach-stm32/Kconfig"
702
703source "arch/arm/mach-sunxi/Kconfig"
704
705source "arch/arm/mach-tegra/Kconfig"
706
707source "arch/arm/mach-uniphier/Kconfig"
708
709source "arch/arm/mach-ux500/Kconfig"
710
711source "arch/arm/mach-versatile/Kconfig"
712
713source "arch/arm/mach-vexpress/Kconfig"
714
715source "arch/arm/mach-vt8500/Kconfig"
716
717source "arch/arm/mach-zynq/Kconfig"
718
719# ARMv7-M architecture
720config ARCH_LPC18XX
721 bool "NXP LPC18xx/LPC43xx"
722 depends on ARM_SINGLE_ARMV7M
723 select ARCH_HAS_RESET_CONTROLLER
724 select ARM_AMBA
725 select CLKSRC_LPC32XX
726 select PINCTRL
727 help
728 Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
729 high performance microcontrollers.
730
731config ARCH_MPS2
732 bool "ARM MPS2 platform"
733 depends on ARM_SINGLE_ARMV7M
734 select ARM_AMBA
735 select CLKSRC_MPS2
736 help
737 Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
738 with a range of available cores like Cortex-M3/M4/M7.
739
740 Please, note that depends which Application Note is used memory map
741 for the platform may vary, so adjustment of RAM base might be needed.
742
743# Definitions to make life easier
744config ARCH_ACORN
745 bool
746
747config PLAT_IOP
748 bool
749
750config PLAT_ORION
751 bool
752 select CLKSRC_MMIO
753 select COMMON_CLK
754 select GENERIC_IRQ_CHIP
755 select IRQ_DOMAIN
756
757config PLAT_ORION_LEGACY
758 bool
759 select PLAT_ORION
760
761config PLAT_PXA
762 bool
763
764config PLAT_VERSATILE
765 bool
766
767source "arch/arm/mm/Kconfig"
768
769config IWMMXT
770 bool "Enable iWMMXt support"
771 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
772 default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
773 help
774 Enable support for iWMMXt context switching at run time if
775 running on a CPU that supports it.
776
777if !MMU
778source "arch/arm/Kconfig-nommu"
779endif
780
781config PJ4B_ERRATA_4742
782 bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
783 depends on CPU_PJ4B && MACH_ARMADA_370
784 default y
785 help
786 When coming out of either a Wait for Interrupt (WFI) or a Wait for
787 Event (WFE) IDLE states, a specific timing sensitivity exists between
788 the retiring WFI/WFE instructions and the newly issued subsequent
789 instructions. This sensitivity can result in a CPU hang scenario.
790 Workaround:
791 The software must insert either a Data Synchronization Barrier (DSB)
792 or Data Memory Barrier (DMB) command immediately after the WFI/WFE
793 instruction
794
795config ARM_ERRATA_326103
796 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
797 depends on CPU_V6
798 help
799 Executing a SWP instruction to read-only memory does not set bit 11
800 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
801 treat the access as a read, preventing a COW from occurring and
802 causing the faulting task to livelock.
803
804config ARM_ERRATA_411920
805 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
806 depends on CPU_V6 || CPU_V6K
807 help
808 Invalidation of the Instruction Cache operation can
809 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
810 It does not affect the MPCore. This option enables the ARM Ltd.
811 recommended workaround.
812
813config ARM_ERRATA_430973
814 bool "ARM errata: Stale prediction on replaced interworking branch"
815 depends on CPU_V7
816 help
817 This option enables the workaround for the 430973 Cortex-A8
818 r1p* erratum. If a code sequence containing an ARM/Thumb
819 interworking branch is replaced with another code sequence at the
820 same virtual address, whether due to self-modifying code or virtual
821 to physical address re-mapping, Cortex-A8 does not recover from the
822 stale interworking branch prediction. This results in Cortex-A8
823 executing the new code sequence in the incorrect ARM or Thumb state.
824 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
825 and also flushes the branch target cache at every context switch.
826 Note that setting specific bits in the ACTLR register may not be
827 available in non-secure mode.
828
829config ARM_ERRATA_458693
830 bool "ARM errata: Processor deadlock when a false hazard is created"
831 depends on CPU_V7
832 depends on !ARCH_MULTIPLATFORM
833 help
834 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
835 erratum. For very specific sequences of memory operations, it is
836 possible for a hazard condition intended for a cache line to instead
837 be incorrectly associated with a different cache line. This false
838 hazard might then cause a processor deadlock. The workaround enables
839 the L1 caching of the NEON accesses and disables the PLD instruction
840 in the ACTLR register. Note that setting specific bits in the ACTLR
841 register may not be available in non-secure mode.
842
843config ARM_ERRATA_460075
844 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
845 depends on CPU_V7
846 depends on !ARCH_MULTIPLATFORM
847 help
848 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
849 erratum. Any asynchronous access to the L2 cache may encounter a
850 situation in which recent store transactions to the L2 cache are lost
851 and overwritten with stale memory contents from external memory. The
852 workaround disables the write-allocate mode for the L2 cache via the
853 ACTLR register. Note that setting specific bits in the ACTLR register
854 may not be available in non-secure mode.
855
856config ARM_ERRATA_742230
857 bool "ARM errata: DMB operation may be faulty"
858 depends on CPU_V7 && SMP
859 depends on !ARCH_MULTIPLATFORM
860 help
861 This option enables the workaround for the 742230 Cortex-A9
862 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
863 between two write operations may not ensure the correct visibility
864 ordering of the two writes. This workaround sets a specific bit in
865 the diagnostic register of the Cortex-A9 which causes the DMB
866 instruction to behave as a DSB, ensuring the correct behaviour of
867 the two writes.
868
869config ARM_ERRATA_742231
870 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
871 depends on CPU_V7 && SMP
872 depends on !ARCH_MULTIPLATFORM
873 help
874 This option enables the workaround for the 742231 Cortex-A9
875 (r2p0..r2p2) erratum. Under certain conditions, specific to the
876 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
877 accessing some data located in the same cache line, may get corrupted
878 data due to bad handling of the address hazard when the line gets
879 replaced from one of the CPUs at the same time as another CPU is
880 accessing it. This workaround sets specific bits in the diagnostic
881 register of the Cortex-A9 which reduces the linefill issuing
882 capabilities of the processor.
883
884config ARM_ERRATA_643719
885 bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
886 depends on CPU_V7 && SMP
887 default y
888 help
889 This option enables the workaround for the 643719 Cortex-A9 (prior to
890 r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
891 register returns zero when it should return one. The workaround
892 corrects this value, ensuring cache maintenance operations which use
893 it behave as intended and avoiding data corruption.
894
895config ARM_ERRATA_720789
896 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
897 depends on CPU_V7
898 help
899 This option enables the workaround for the 720789 Cortex-A9 (prior to
900 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
901 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
902 As a consequence of this erratum, some TLB entries which should be
903 invalidated are not, resulting in an incoherency in the system page
904 tables. The workaround changes the TLB flushing routines to invalidate
905 entries regardless of the ASID.
906
907config ARM_ERRATA_743622
908 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
909 depends on CPU_V7
910 depends on !ARCH_MULTIPLATFORM
911 help
912 This option enables the workaround for the 743622 Cortex-A9
913 (r2p*) erratum. Under very rare conditions, a faulty
914 optimisation in the Cortex-A9 Store Buffer may lead to data
915 corruption. This workaround sets a specific bit in the diagnostic
916 register of the Cortex-A9 which disables the Store Buffer
917 optimisation, preventing the defect from occurring. This has no
918 visible impact on the overall performance or power consumption of the
919 processor.
920
921config ARM_ERRATA_751472
922 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
923 depends on CPU_V7
924 depends on !ARCH_MULTIPLATFORM
925 help
926 This option enables the workaround for the 751472 Cortex-A9 (prior
927 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
928 completion of a following broadcasted operation if the second
929 operation is received by a CPU before the ICIALLUIS has completed,
930 potentially leading to corrupted entries in the cache or TLB.
931
932config ARM_ERRATA_754322
933 bool "ARM errata: possible faulty MMU translations following an ASID switch"
934 depends on CPU_V7
935 help
936 This option enables the workaround for the 754322 Cortex-A9 (r2p*,
937 r3p*) erratum. A speculative memory access may cause a page table walk
938 which starts prior to an ASID switch but completes afterwards. This
939 can populate the micro-TLB with a stale entry which may be hit with
940 the new ASID. This workaround places two dsb instructions in the mm
941 switching code so that no page table walks can cross the ASID switch.
942
943config ARM_ERRATA_754327
944 bool "ARM errata: no automatic Store Buffer drain"
945 depends on CPU_V7 && SMP
946 help
947 This option enables the workaround for the 754327 Cortex-A9 (prior to
948 r2p0) erratum. The Store Buffer does not have any automatic draining
949 mechanism and therefore a livelock may occur if an external agent
950 continuously polls a memory location waiting to observe an update.
951 This workaround defines cpu_relax() as smp_mb(), preventing correctly
952 written polling loops from denying visibility of updates to memory.
953
954config ARM_ERRATA_364296
955 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
956 depends on CPU_V6
957 help
958 This options enables the workaround for the 364296 ARM1136
959 r0p2 erratum (possible cache data corruption with
960 hit-under-miss enabled). It sets the undocumented bit 31 in
961 the auxiliary control register and the FI bit in the control
962 register, thus disabling hit-under-miss without putting the
963 processor into full low interrupt latency mode. ARM11MPCore
964 is not affected.
965
966config ARM_ERRATA_764369
967 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
968 depends on CPU_V7 && SMP
969 help
970 This option enables the workaround for erratum 764369
971 affecting Cortex-A9 MPCore with two or more processors (all
972 current revisions). Under certain timing circumstances, a data
973 cache line maintenance operation by MVA targeting an Inner
974 Shareable memory region may fail to proceed up to either the
975 Point of Coherency or to the Point of Unification of the
976 system. This workaround adds a DSB instruction before the
977 relevant cache maintenance functions and sets a specific bit
978 in the diagnostic control register of the SCU.
979
980config ARM_ERRATA_775420
981 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
982 depends on CPU_V7
983 help
984 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
985 r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
986 operation aborts with MMU exception, it might cause the processor
987 to deadlock. This workaround puts DSB before executing ISB if
988 an abort may occur on cache maintenance.
989
990config ARM_ERRATA_798181
991 bool "ARM errata: TLBI/DSB failure on Cortex-A15"
992 depends on CPU_V7 && SMP
993 help
994 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
995 adequately shooting down all use of the old entries. This
996 option enables the Linux kernel workaround for this erratum
997 which sends an IPI to the CPUs that are running the same ASID
998 as the one being invalidated.
999
1000config ARM_ERRATA_773022
1001 bool "ARM errata: incorrect instructions may be executed from loop buffer"
1002 depends on CPU_V7
1003 help
1004 This option enables the workaround for the 773022 Cortex-A15
1005 (up to r0p4) erratum. In certain rare sequences of code, the
1006 loop buffer may deliver incorrect instructions. This
1007 workaround disables the loop buffer to avoid the erratum.
1008
1009config ARM_ERRATA_818325_852422
1010 bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
1011 depends on CPU_V7
1012 help
1013 This option enables the workaround for:
1014 - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
1015 instruction might deadlock. Fixed in r0p1.
1016 - Cortex-A12 852422: Execution of a sequence of instructions might
1017 lead to either a data corruption or a CPU deadlock. Not fixed in
1018 any Cortex-A12 cores yet.
1019 This workaround for all both errata involves setting bit[12] of the
1020 Feature Register. This bit disables an optimisation applied to a
1021 sequence of 2 instructions that use opposing condition codes.
1022
1023config ARM_ERRATA_821420
1024 bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
1025 depends on CPU_V7
1026 help
1027 This option enables the workaround for the 821420 Cortex-A12
1028 (all revs) erratum. In very rare timing conditions, a sequence
1029 of VMOV to Core registers instructions, for which the second
1030 one is in the shadow of a branch or abort, can lead to a
1031 deadlock when the VMOV instructions are issued out-of-order.
1032
1033config ARM_ERRATA_825619
1034 bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
1035 depends on CPU_V7
1036 help
1037 This option enables the workaround for the 825619 Cortex-A12
1038 (all revs) erratum. Within rare timing constraints, executing a
1039 DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
1040 and Device/Strongly-Ordered loads and stores might cause deadlock
1041
1042config ARM_ERRATA_857271
1043 bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
1044 depends on CPU_V7
1045 help
1046 This option enables the workaround for the 857271 Cortex-A12
1047 (all revs) erratum. Under very rare timing conditions, the CPU might
1048 hang. The workaround is expected to have a < 1% performance impact.
1049
1050config ARM_ERRATA_852421
1051 bool "ARM errata: A17: DMB ST might fail to create order between stores"
1052 depends on CPU_V7
1053 help
1054 This option enables the workaround for the 852421 Cortex-A17
1055 (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
1056 execution of a DMB ST instruction might fail to properly order
1057 stores from GroupA and stores from GroupB.
1058
1059config ARM_ERRATA_852423
1060 bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
1061 depends on CPU_V7
1062 help
1063 This option enables the workaround for:
1064 - Cortex-A17 852423: Execution of a sequence of instructions might
1065 lead to either a data corruption or a CPU deadlock. Not fixed in
1066 any Cortex-A17 cores yet.
1067 This is identical to Cortex-A12 erratum 852422. It is a separate
1068 config option from the A12 erratum due to the way errata are checked
1069 for and handled.
1070
1071config ARM_ERRATA_857272
1072 bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
1073 depends on CPU_V7
1074 help
1075 This option enables the workaround for the 857272 Cortex-A17 erratum.
1076 This erratum is not known to be fixed in any A17 revision.
1077 This is identical to Cortex-A12 erratum 857271. It is a separate
1078 config option from the A12 erratum due to the way errata are checked
1079 for and handled.
1080
1081endmenu
1082
1083source "arch/arm/common/Kconfig"
1084
1085menu "Bus support"
1086
1087config ISA
1088 bool
1089 help
1090 Find out whether you have ISA slots on your motherboard. ISA is the
1091 name of a bus system, i.e. the way the CPU talks to the other stuff
1092 inside your box. Other bus systems are PCI, EISA, MicroChannel
1093 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1094 newer boards don't support it. If you have ISA, say Y, otherwise N.
1095
1096# Select ISA DMA controller support
1097config ISA_DMA
1098 bool
1099 select ISA_DMA_API
1100
1101# Select ISA DMA interface
1102config ISA_DMA_API
1103 bool
1104
1105config PCI_NANOENGINE
1106 bool "BSE nanoEngine PCI support"
1107 depends on SA1100_NANOENGINE
1108 help
1109 Enable PCI on the BSE nanoEngine board.
1110
1111config ARM_ERRATA_814220
1112 bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
1113 depends on CPU_V7
1114 help
1115 The v7 ARM states that all cache and branch predictor maintenance
1116 operations that do not specify an address execute, relative to
1117 each other, in program order.
1118 However, because of this erratum, an L2 set/way cache maintenance
1119 operation can overtake an L1 set/way cache maintenance operation.
1120 This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
1121 r0p4, r0p5.
1122
1123endmenu
1124
1125menu "Kernel Features"
1126
1127config HAVE_SMP
1128 bool
1129 help
1130 This option should be selected by machines which have an SMP-
1131 capable CPU.
1132
1133 The only effect of this option is to make the SMP-related
1134 options available to the user for configuration.
1135
1136config SMP
1137 bool "Symmetric Multi-Processing"
1138 depends on CPU_V6K || CPU_V7
1139 depends on HAVE_SMP
1140 depends on MMU || ARM_MPU
1141 select IRQ_WORK
1142 help
1143 This enables support for systems with more than one CPU. If you have
1144 a system with only one CPU, say N. If you have a system with more
1145 than one CPU, say Y.
1146
1147 If you say N here, the kernel will run on uni- and multiprocessor
1148 machines, but will use only one CPU of a multiprocessor machine. If
1149 you say Y here, the kernel will run on many, but not all,
1150 uniprocessor machines. On a uniprocessor machine, the kernel
1151 will run faster if you say N here.
1152
1153 See also <file:Documentation/x86/i386/IO-APIC.rst>,
1154 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
1155 <http://tldp.org/HOWTO/SMP-HOWTO.html>.
1156
1157 If you don't know what to do here, say N.
1158
1159config SMP_ON_UP
1160 bool "Allow booting SMP kernel on uniprocessor systems"
1161 depends on SMP && !XIP_KERNEL && MMU
1162 default y
1163 help
1164 SMP kernels contain instructions which fail on non-SMP processors.
1165 Enabling this option allows the kernel to modify itself to make
1166 these instructions safe. Disabling it allows about 1K of space
1167 savings.
1168
1169 If you don't know what to do here, say Y.
1170
1171config ARM_CPU_TOPOLOGY
1172 bool "Support cpu topology definition"
1173 depends on SMP && CPU_V7
1174 default y
1175 help
1176 Support ARM cpu topology definition. The MPIDR register defines
1177 affinity between processors which is then used to describe the cpu
1178 topology of an ARM System.
1179
1180config SCHED_MC
1181 bool "Multi-core scheduler support"
1182 depends on ARM_CPU_TOPOLOGY
1183 help
1184 Multi-core scheduler support improves the CPU scheduler's decision
1185 making when dealing with multi-core CPU chips at a cost of slightly
1186 increased overhead in some places. If unsure say N here.
1187
1188config SCHED_SMT
1189 bool "SMT scheduler support"
1190 depends on ARM_CPU_TOPOLOGY
1191 help
1192 Improves the CPU scheduler's decision making when dealing with
1193 MultiThreading at a cost of slightly increased overhead in some
1194 places. If unsure say N here.
1195
1196config HAVE_ARM_SCU
1197 bool
1198 help
1199 This option enables support for the ARM snoop control unit
1200
1201config HAVE_ARM_ARCH_TIMER
1202 bool "Architected timer support"
1203 depends on CPU_V7
1204 select ARM_ARCH_TIMER
1205 help
1206 This option enables support for the ARM architected timer
1207
1208config HAVE_ARM_TWD
1209 bool
1210 help
1211 This options enables support for the ARM timer and watchdog unit
1212
1213config MCPM
1214 bool "Multi-Cluster Power Management"
1215 depends on CPU_V7 && SMP
1216 help
1217 This option provides the common power management infrastructure
1218 for (multi-)cluster based systems, such as big.LITTLE based
1219 systems.
1220
1221config MCPM_QUAD_CLUSTER
1222 bool
1223 depends on MCPM
1224 help
1225 To avoid wasting resources unnecessarily, MCPM only supports up
1226 to 2 clusters by default.
1227 Platforms with 3 or 4 clusters that use MCPM must select this
1228 option to allow the additional clusters to be managed.
1229
1230config BIG_LITTLE
1231 bool "big.LITTLE support (Experimental)"
1232 depends on CPU_V7 && SMP
1233 select MCPM
1234 help
1235 This option enables support selections for the big.LITTLE
1236 system architecture.
1237
1238config BL_SWITCHER
1239 bool "big.LITTLE switcher support"
1240 depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
1241 select CPU_PM
1242 help
1243 The big.LITTLE "switcher" provides the core functionality to
1244 transparently handle transition between a cluster of A15's
1245 and a cluster of A7's in a big.LITTLE system.
1246
1247config BL_SWITCHER_DUMMY_IF
1248 tristate "Simple big.LITTLE switcher user interface"
1249 depends on BL_SWITCHER && DEBUG_KERNEL
1250 help
1251 This is a simple and dummy char dev interface to control
1252 the big.LITTLE switcher core code. It is meant for
1253 debugging purposes only.
1254
1255choice
1256 prompt "Memory split"
1257 depends on MMU
1258 default VMSPLIT_3G
1259 help
1260 Select the desired split between kernel and user memory.
1261
1262 If you are not absolutely sure what you are doing, leave this
1263 option alone!
1264
1265 config VMSPLIT_3G
1266 bool "3G/1G user/kernel split"
1267 config VMSPLIT_3G_OPT
1268 depends on !ARM_LPAE
1269 bool "3G/1G user/kernel split (for full 1G low memory)"
1270 config VMSPLIT_2G
1271 bool "2G/2G user/kernel split"
1272 config VMSPLIT_1G
1273 bool "1G/3G user/kernel split"
1274endchoice
1275
1276config PAGE_OFFSET
1277 hex
1278 default PHYS_OFFSET if !MMU
1279 default 0x40000000 if VMSPLIT_1G
1280 default 0x80000000 if VMSPLIT_2G
1281 default 0xB0000000 if VMSPLIT_3G_OPT
1282 default 0xC0000000
1283
1284config KASAN_SHADOW_OFFSET
1285 hex
1286 depends on KASAN
1287 default 0x1f000000 if PAGE_OFFSET=0x40000000
1288 default 0x5f000000 if PAGE_OFFSET=0x80000000
1289 default 0x9f000000 if PAGE_OFFSET=0xC0000000
1290 default 0x8f000000 if PAGE_OFFSET=0xB0000000
1291 default 0xffffffff
1292
1293config NR_CPUS
1294 int "Maximum number of CPUs (2-32)"
1295 range 2 16 if DEBUG_KMAP_LOCAL
1296 range 2 32 if !DEBUG_KMAP_LOCAL
1297 depends on SMP
1298 default "4"
1299 help
1300 The maximum number of CPUs that the kernel can support.
1301 Up to 32 CPUs can be supported, or up to 16 if kmap_local()
1302 debugging is enabled, which uses half of the per-CPU fixmap
1303 slots as guard regions.
1304
1305config HOTPLUG_CPU
1306 bool "Support for hot-pluggable CPUs"
1307 depends on SMP
1308 select GENERIC_IRQ_MIGRATION
1309 help
1310 Say Y here to experiment with turning CPUs off and on. CPUs
1311 can be controlled through /sys/devices/system/cpu.
1312
1313config ARM_PSCI
1314 bool "Support for the ARM Power State Coordination Interface (PSCI)"
1315 depends on HAVE_ARM_SMCCC
1316 select ARM_PSCI_FW
1317 help
1318 Say Y here if you want Linux to communicate with system firmware
1319 implementing the PSCI specification for CPU-centric power
1320 management operations described in ARM document number ARM DEN
1321 0022A ("Power State Coordination Interface System Software on
1322 ARM processors").
1323
1324# The GPIO number here must be sorted by descending number. In case of
1325# a multiplatform kernel, we just want the highest value required by the
1326# selected platforms.
1327config ARCH_NR_GPIO
1328 int
1329 default 2048 if ARCH_INTEL_SOCFPGA
1330 default 1024 if ARCH_BRCMSTB || ARCH_RENESAS || ARCH_TEGRA || \
1331 ARCH_ZYNQ || ARCH_ASPEED
1332 default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \
1333 SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210
1334 default 416 if ARCH_SUNXI
1335 default 392 if ARCH_U8500
1336 default 352 if ARCH_VT8500
1337 default 288 if ARCH_ROCKCHIP
1338 default 264 if MACH_H4700
1339 default 0
1340 help
1341 Maximum number of GPIOs in the system.
1342
1343 If unsure, leave the default value.
1344
1345config HZ_FIXED
1346 int
1347 default 128 if SOC_AT91RM9200
1348 default 0
1349
1350choice
1351 depends on HZ_FIXED = 0
1352 prompt "Timer frequency"
1353
1354config HZ_100
1355 bool "100 Hz"
1356
1357config HZ_200
1358 bool "200 Hz"
1359
1360config HZ_250
1361 bool "250 Hz"
1362
1363config HZ_300
1364 bool "300 Hz"
1365
1366config HZ_500
1367 bool "500 Hz"
1368
1369config HZ_1000
1370 bool "1000 Hz"
1371
1372endchoice
1373
1374config HZ
1375 int
1376 default HZ_FIXED if HZ_FIXED != 0
1377 default 100 if HZ_100
1378 default 200 if HZ_200
1379 default 250 if HZ_250
1380 default 300 if HZ_300
1381 default 500 if HZ_500
1382 default 1000
1383
1384config SCHED_HRTICK
1385 def_bool HIGH_RES_TIMERS
1386
1387config THUMB2_KERNEL
1388 bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1389 depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1390 default y if CPU_THUMBONLY
1391 select ARM_UNWIND
1392 help
1393 By enabling this option, the kernel will be compiled in
1394 Thumb-2 mode.
1395
1396 If unsure, say N.
1397
1398config ARM_PATCH_IDIV
1399 bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
1400 depends on CPU_32v7 && !XIP_KERNEL
1401 default y
1402 help
1403 The ARM compiler inserts calls to __aeabi_idiv() and
1404 __aeabi_uidiv() when it needs to perform division on signed
1405 and unsigned integers. Some v7 CPUs have support for the sdiv
1406 and udiv instructions that can be used to implement those
1407 functions.
1408
1409 Enabling this option allows the kernel to modify itself to
1410 replace the first two instructions of these library functions
1411 with the sdiv or udiv plus "bx lr" instructions when the CPU
1412 it is running on supports them. Typically this will be faster
1413 and less power intensive than running the original library
1414 code to do integer division.
1415
1416config AEABI
1417 bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1418 !CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1419 default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
1420 help
1421 This option allows for the kernel to be compiled using the latest
1422 ARM ABI (aka EABI). This is only useful if you are using a user
1423 space environment that is also compiled with EABI.
1424
1425 Since there are major incompatibilities between the legacy ABI and
1426 EABI, especially with regard to structure member alignment, this
1427 option also changes the kernel syscall calling convention to
1428 disambiguate both ABIs and allow for backward compatibility support
1429 (selected with CONFIG_OABI_COMPAT).
1430
1431 To use this you need GCC version 4.0.0 or later.
1432
1433config OABI_COMPAT
1434 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1435 depends on AEABI && !THUMB2_KERNEL
1436 help
1437 This option preserves the old syscall interface along with the
1438 new (ARM EABI) one. It also provides a compatibility layer to
1439 intercept syscalls that have structure arguments which layout
1440 in memory differs between the legacy ABI and the new ARM EABI
1441 (only for non "thumb" binaries). This option adds a tiny
1442 overhead to all syscalls and produces a slightly larger kernel.
1443
1444 The seccomp filter system will not be available when this is
1445 selected, since there is no way yet to sensibly distinguish
1446 between calling conventions during filtering.
1447
1448 If you know you'll be using only pure EABI user space then you
1449 can say N here. If this option is not selected and you attempt
1450 to execute a legacy ABI binary then the result will be
1451 UNPREDICTABLE (in fact it can be predicted that it won't work
1452 at all). If in doubt say N.
1453
1454config ARCH_SELECT_MEMORY_MODEL
1455 bool
1456
1457config ARCH_FLATMEM_ENABLE
1458 bool
1459
1460config ARCH_SPARSEMEM_ENABLE
1461 bool
1462 select SPARSEMEM_STATIC if SPARSEMEM
1463
1464config HIGHMEM
1465 bool "High Memory Support"
1466 depends on MMU
1467 select KMAP_LOCAL
1468 help
1469 The address space of ARM processors is only 4 Gigabytes large
1470 and it has to accommodate user address space, kernel address
1471 space as well as some memory mapped IO. That means that, if you
1472 have a large amount of physical memory and/or IO, not all of the
1473 memory can be "permanently mapped" by the kernel. The physical
1474 memory that is not permanently mapped is called "high memory".
1475
1476 Depending on the selected kernel/user memory split, minimum
1477 vmalloc space and actual amount of RAM, you may not need this
1478 option which should result in a slightly faster kernel.
1479
1480 If unsure, say n.
1481
1482config HIGHPTE
1483 bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1484 depends on HIGHMEM
1485 default y
1486 help
1487 The VM uses one page of physical memory for each page table.
1488 For systems with a lot of processes, this can use a lot of
1489 precious low memory, eventually leading to low memory being
1490 consumed by page tables. Setting this option will allow
1491 user-space 2nd level page tables to reside in high memory.
1492
1493config CPU_SW_DOMAIN_PAN
1494 bool "Enable use of CPU domains to implement privileged no-access"
1495 depends on MMU && !ARM_LPAE
1496 default y
1497 help
1498 Increase kernel security by ensuring that normal kernel accesses
1499 are unable to access userspace addresses. This can help prevent
1500 use-after-free bugs becoming an exploitable privilege escalation
1501 by ensuring that magic values (such as LIST_POISON) will always
1502 fault when dereferenced.
1503
1504 CPUs with low-vector mappings use a best-efforts implementation.
1505 Their lower 1MB needs to remain accessible for the vectors, but
1506 the remainder of userspace will become appropriately inaccessible.
1507
1508config HW_PERF_EVENTS
1509 def_bool y
1510 depends on ARM_PMU
1511
1512config ARCH_WANT_GENERAL_HUGETLB
1513 def_bool y
1514
1515config ARM_MODULE_PLTS
1516 bool "Use PLTs to allow module memory to spill over into vmalloc area"
1517 depends on MODULES
1518 default y
1519 help
1520 Allocate PLTs when loading modules so that jumps and calls whose
1521 targets are too far away for their relative offsets to be encoded
1522 in the instructions themselves can be bounced via veneers in the
1523 module's PLT. This allows modules to be allocated in the generic
1524 vmalloc area after the dedicated module memory area has been
1525 exhausted. The modules will use slightly more memory, but after
1526 rounding up to page size, the actual memory footprint is usually
1527 the same.
1528
1529 Disabling this is usually safe for small single-platform
1530 configurations. If unsure, say y.
1531
1532config FORCE_MAX_ZONEORDER
1533 int "Maximum zone order"
1534 default "12" if SOC_AM33XX
1535 default "9" if SA1111
1536 default "11"
1537 help
1538 The kernel memory allocator divides physically contiguous memory
1539 blocks into "zones", where each zone is a power of two number of
1540 pages. This option selects the largest power of two that the kernel
1541 keeps in the memory allocator. If you need to allocate very large
1542 blocks of physically contiguous memory, then you may need to
1543 increase this value.
1544
1545 This config option is actually maximum order plus one. For example,
1546 a value of 11 means that the largest free memory block is 2^10 pages.
1547
1548config ALIGNMENT_TRAP
1549 def_bool CPU_CP15_MMU
1550 select HAVE_PROC_CPU if PROC_FS
1551 help
1552 ARM processors cannot fetch/store information which is not
1553 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1554 address divisible by 4. On 32-bit ARM processors, these non-aligned
1555 fetch/store instructions will be emulated in software if you say
1556 here, which has a severe performance impact. This is necessary for
1557 correct operation of some network protocols. With an IP-only
1558 configuration it is safe to say N, otherwise say Y.
1559
1560config UACCESS_WITH_MEMCPY
1561 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1562 depends on MMU
1563 default y if CPU_FEROCEON
1564 help
1565 Implement faster copy_to_user and clear_user methods for CPU
1566 cores where a 8-word STM instruction give significantly higher
1567 memory write throughput than a sequence of individual 32bit stores.
1568
1569 A possible side effect is a slight increase in scheduling latency
1570 between threads sharing the same address space if they invoke
1571 such copy operations with large buffers.
1572
1573 However, if the CPU data cache is using a write-allocate mode,
1574 this option is unlikely to provide any performance gain.
1575
1576config PARAVIRT
1577 bool "Enable paravirtualization code"
1578 help
1579 This changes the kernel so it can modify itself when it is run
1580 under a hypervisor, potentially improving performance significantly
1581 over full virtualization.
1582
1583config PARAVIRT_TIME_ACCOUNTING
1584 bool "Paravirtual steal time accounting"
1585 select PARAVIRT
1586 help
1587 Select this option to enable fine granularity task steal time
1588 accounting. Time spent executing other tasks in parallel with
1589 the current vCPU is discounted from the vCPU power. To account for
1590 that, there can be a small performance impact.
1591
1592 If in doubt, say N here.
1593
1594config XEN_DOM0
1595 def_bool y
1596 depends on XEN
1597
1598config XEN
1599 bool "Xen guest support on ARM"
1600 depends on ARM && AEABI && OF
1601 depends on CPU_V7 && !CPU_V6
1602 depends on !GENERIC_ATOMIC64
1603 depends on MMU
1604 select ARCH_DMA_ADDR_T_64BIT
1605 select ARM_PSCI
1606 select SWIOTLB
1607 select SWIOTLB_XEN
1608 select PARAVIRT
1609 help
1610 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1611
1612config STACKPROTECTOR_PER_TASK
1613 bool "Use a unique stack canary value for each task"
1614 depends on GCC_PLUGINS && STACKPROTECTOR && SMP && !XIP_DEFLATED_DATA
1615 select GCC_PLUGIN_ARM_SSP_PER_TASK
1616 default y
1617 help
1618 Due to the fact that GCC uses an ordinary symbol reference from
1619 which to load the value of the stack canary, this value can only
1620 change at reboot time on SMP systems, and all tasks running in the
1621 kernel's address space are forced to use the same canary value for
1622 the entire duration that the system is up.
1623
1624 Enable this option to switch to a different method that uses a
1625 different canary value for each task.
1626
1627endmenu
1628
1629menu "Boot options"
1630
1631config USE_OF
1632 bool "Flattened Device Tree support"
1633 select IRQ_DOMAIN
1634 select OF
1635 help
1636 Include support for flattened device tree machine descriptions.
1637
1638config ATAGS
1639 bool "Support for the traditional ATAGS boot data passing" if USE_OF
1640 default y
1641 help
1642 This is the traditional way of passing data to the kernel at boot
1643 time. If you are solely relying on the flattened device tree (or
1644 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1645 to remove ATAGS support from your kernel binary. If unsure,
1646 leave this to y.
1647
1648config DEPRECATED_PARAM_STRUCT
1649 bool "Provide old way to pass kernel parameters"
1650 depends on ATAGS
1651 help
1652 This was deprecated in 2001 and announced to live on for 5 years.
1653 Some old boot loaders still use this way.
1654
1655# Compressed boot loader in ROM. Yes, we really want to ask about
1656# TEXT and BSS so we preserve their values in the config files.
1657config ZBOOT_ROM_TEXT
1658 hex "Compressed ROM boot loader base address"
1659 default 0x0
1660 help
1661 The physical address at which the ROM-able zImage is to be
1662 placed in the target. Platforms which normally make use of
1663 ROM-able zImage formats normally set this to a suitable
1664 value in their defconfig file.
1665
1666 If ZBOOT_ROM is not enabled, this has no effect.
1667
1668config ZBOOT_ROM_BSS
1669 hex "Compressed ROM boot loader BSS address"
1670 default 0x0
1671 help
1672 The base address of an area of read/write memory in the target
1673 for the ROM-able zImage which must be available while the
1674 decompressor is running. It must be large enough to hold the
1675 entire decompressed kernel plus an additional 128 KiB.
1676 Platforms which normally make use of ROM-able zImage formats
1677 normally set this to a suitable value in their defconfig file.
1678
1679 If ZBOOT_ROM is not enabled, this has no effect.
1680
1681config ZBOOT_ROM
1682 bool "Compressed boot loader in ROM/flash"
1683 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1684 depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1685 help
1686 Say Y here if you intend to execute your compressed kernel image
1687 (zImage) directly from ROM or flash. If unsure, say N.
1688
1689config ARM_APPENDED_DTB
1690 bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1691 depends on OF
1692 help
1693 With this option, the boot code will look for a device tree binary
1694 (DTB) appended to zImage
1695 (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1696
1697 This is meant as a backward compatibility convenience for those
1698 systems with a bootloader that can't be upgraded to accommodate
1699 the documented boot protocol using a device tree.
1700
1701 Beware that there is very little in terms of protection against
1702 this option being confused by leftover garbage in memory that might
1703 look like a DTB header after a reboot if no actual DTB is appended
1704 to zImage. Do not leave this option active in a production kernel
1705 if you don't intend to always append a DTB. Proper passing of the
1706 location into r2 of a bootloader provided DTB is always preferable
1707 to this option.
1708
1709config ARM_ATAG_DTB_COMPAT
1710 bool "Supplement the appended DTB with traditional ATAG information"
1711 depends on ARM_APPENDED_DTB
1712 help
1713 Some old bootloaders can't be updated to a DTB capable one, yet
1714 they provide ATAGs with memory configuration, the ramdisk address,
1715 the kernel cmdline string, etc. Such information is dynamically
1716 provided by the bootloader and can't always be stored in a static
1717 DTB. To allow a device tree enabled kernel to be used with such
1718 bootloaders, this option allows zImage to extract the information
1719 from the ATAG list and store it at run time into the appended DTB.
1720
1721choice
1722 prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1723 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1724
1725config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1726 bool "Use bootloader kernel arguments if available"
1727 help
1728 Uses the command-line options passed by the boot loader instead of
1729 the device tree bootargs property. If the boot loader doesn't provide
1730 any, the device tree bootargs property will be used.
1731
1732config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1733 bool "Extend with bootloader kernel arguments"
1734 help
1735 The command-line arguments provided by the boot loader will be
1736 appended to the the device tree bootargs property.
1737
1738endchoice
1739
1740config CMDLINE
1741 string "Default kernel command string"
1742 default ""
1743 help
1744 On some architectures (e.g. CATS), there is currently no way
1745 for the boot loader to pass arguments to the kernel. For these
1746 architectures, you should supply some command-line options at build
1747 time by entering them here. As a minimum, you should specify the
1748 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1749
1750choice
1751 prompt "Kernel command line type" if CMDLINE != ""
1752 default CMDLINE_FROM_BOOTLOADER
1753 depends on ATAGS
1754
1755config CMDLINE_FROM_BOOTLOADER
1756 bool "Use bootloader kernel arguments if available"
1757 help
1758 Uses the command-line options passed by the boot loader. If
1759 the boot loader doesn't provide any, the default kernel command
1760 string provided in CMDLINE will be used.
1761
1762config CMDLINE_EXTEND
1763 bool "Extend bootloader kernel arguments"
1764 help
1765 The command-line arguments provided by the boot loader will be
1766 appended to the default kernel command string.
1767
1768config CMDLINE_FORCE
1769 bool "Always use the default kernel command string"
1770 help
1771 Always use the default kernel command string, even if the boot
1772 loader passes other arguments to the kernel.
1773 This is useful if you cannot or don't want to change the
1774 command-line options your boot loader passes to the kernel.
1775endchoice
1776
1777config XIP_KERNEL
1778 bool "Kernel Execute-In-Place from ROM"
1779 depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
1780 help
1781 Execute-In-Place allows the kernel to run from non-volatile storage
1782 directly addressable by the CPU, such as NOR flash. This saves RAM
1783 space since the text section of the kernel is not loaded from flash
1784 to RAM. Read-write sections, such as the data section and stack,
1785 are still copied to RAM. The XIP kernel is not compressed since
1786 it has to run directly from flash, so it will take more space to
1787 store it. The flash address used to link the kernel object files,
1788 and for storing it, is configuration dependent. Therefore, if you
1789 say Y here, you must know the proper physical address where to
1790 store the kernel image depending on your own flash memory usage.
1791
1792 Also note that the make target becomes "make xipImage" rather than
1793 "make zImage" or "make Image". The final kernel binary to put in
1794 ROM memory will be arch/arm/boot/xipImage.
1795
1796 If unsure, say N.
1797
1798config XIP_PHYS_ADDR
1799 hex "XIP Kernel Physical Location"
1800 depends on XIP_KERNEL
1801 default "0x00080000"
1802 help
1803 This is the physical address in your flash memory the kernel will
1804 be linked for and stored to. This address is dependent on your
1805 own flash usage.
1806
1807config XIP_DEFLATED_DATA
1808 bool "Store kernel .data section compressed in ROM"
1809 depends on XIP_KERNEL
1810 select ZLIB_INFLATE
1811 help
1812 Before the kernel is actually executed, its .data section has to be
1813 copied to RAM from ROM. This option allows for storing that data
1814 in compressed form and decompressed to RAM rather than merely being
1815 copied, saving some precious ROM space. A possible drawback is a
1816 slightly longer boot delay.
1817
1818config KEXEC
1819 bool "Kexec system call (EXPERIMENTAL)"
1820 depends on (!SMP || PM_SLEEP_SMP)
1821 depends on MMU
1822 select KEXEC_CORE
1823 help
1824 kexec is a system call that implements the ability to shutdown your
1825 current kernel, and to start another kernel. It is like a reboot
1826 but it is independent of the system firmware. And like a reboot
1827 you can start any kernel with it, not just Linux.
1828
1829 It is an ongoing process to be certain the hardware in a machine
1830 is properly shutdown, so do not be surprised if this code does not
1831 initially work for you.
1832
1833config ATAGS_PROC
1834 bool "Export atags in procfs"
1835 depends on ATAGS && KEXEC
1836 default y
1837 help
1838 Should the atags used to boot the kernel be exported in an "atags"
1839 file in procfs. Useful with kexec.
1840
1841config CRASH_DUMP
1842 bool "Build kdump crash kernel (EXPERIMENTAL)"
1843 help
1844 Generate crash dump after being started by kexec. This should
1845 be normally only set in special crash dump kernels which are
1846 loaded in the main kernel with kexec-tools into a specially
1847 reserved region and then later executed after a crash by
1848 kdump/kexec. The crash dump kernel must be compiled to a
1849 memory address not used by the main kernel
1850
1851 For more details see Documentation/admin-guide/kdump/kdump.rst
1852
1853config AUTO_ZRELADDR
1854 bool "Auto calculation of the decompressed kernel image address"
1855 help
1856 ZRELADDR is the physical address where the decompressed kernel
1857 image will be placed. If AUTO_ZRELADDR is selected, the address
1858 will be determined at run-time, either by masking the current IP
1859 with 0xf8000000, or, if invalid, from the DTB passed in r2.
1860 This assumes the zImage being placed in the first 128MB from
1861 start of memory.
1862
1863config EFI_STUB
1864 bool
1865
1866config EFI
1867 bool "UEFI runtime support"
1868 depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
1869 select UCS2_STRING
1870 select EFI_PARAMS_FROM_FDT
1871 select EFI_STUB
1872 select EFI_GENERIC_STUB
1873 select EFI_RUNTIME_WRAPPERS
1874 help
1875 This option provides support for runtime services provided
1876 by UEFI firmware (such as non-volatile variables, realtime
1877 clock, and platform reset). A UEFI stub is also provided to
1878 allow the kernel to be booted as an EFI application. This
1879 is only useful for kernels that may run on systems that have
1880 UEFI firmware.
1881
1882config DMI
1883 bool "Enable support for SMBIOS (DMI) tables"
1884 depends on EFI
1885 default y
1886 help
1887 This enables SMBIOS/DMI feature for systems.
1888
1889 This option is only useful on systems that have UEFI firmware.
1890 However, even with this option, the resultant kernel should
1891 continue to boot on existing non-UEFI platforms.
1892
1893 NOTE: This does *NOT* enable or encourage the use of DMI quirks,
1894 i.e., the the practice of identifying the platform via DMI to
1895 decide whether certain workarounds for buggy hardware and/or
1896 firmware need to be enabled. This would require the DMI subsystem
1897 to be enabled much earlier than we do on ARM, which is non-trivial.
1898
1899endmenu
1900
1901menu "CPU Power Management"
1902
1903source "drivers/cpufreq/Kconfig"
1904
1905source "drivers/cpuidle/Kconfig"
1906
1907endmenu
1908
1909menu "Floating point emulation"
1910
1911comment "At least one emulation must be selected"
1912
1913config FPE_NWFPE
1914 bool "NWFPE math emulation"
1915 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
1916 help
1917 Say Y to include the NWFPE floating point emulator in the kernel.
1918 This is necessary to run most binaries. Linux does not currently
1919 support floating point hardware so you need to say Y here even if
1920 your machine has an FPA or floating point co-processor podule.
1921
1922 You may say N here if you are going to load the Acorn FPEmulator
1923 early in the bootup.
1924
1925config FPE_NWFPE_XP
1926 bool "Support extended precision"
1927 depends on FPE_NWFPE
1928 help
1929 Say Y to include 80-bit support in the kernel floating-point
1930 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1931 Note that gcc does not generate 80-bit operations by default,
1932 so in most cases this option only enlarges the size of the
1933 floating point emulator without any good reason.
1934
1935 You almost surely want to say N here.
1936
1937config FPE_FASTFPE
1938 bool "FastFPE math emulation (EXPERIMENTAL)"
1939 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
1940 help
1941 Say Y here to include the FAST floating point emulator in the kernel.
1942 This is an experimental much faster emulator which now also has full
1943 precision for the mantissa. It does not support any exceptions.
1944 It is very simple, and approximately 3-6 times faster than NWFPE.
1945
1946 It should be sufficient for most programs. It may be not suitable
1947 for scientific calculations, but you have to check this for yourself.
1948 If you do not feel you need a faster FP emulation you should better
1949 choose NWFPE.
1950
1951config VFP
1952 bool "VFP-format floating point maths"
1953 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1954 help
1955 Say Y to include VFP support code in the kernel. This is needed
1956 if your hardware includes a VFP unit.
1957
1958 Please see <file:Documentation/arm/vfp/release-notes.rst> for
1959 release notes and additional status information.
1960
1961 Say N if your target does not have VFP hardware.
1962
1963config VFPv3
1964 bool
1965 depends on VFP
1966 default y if CPU_V7
1967
1968config NEON
1969 bool "Advanced SIMD (NEON) Extension support"
1970 depends on VFPv3 && CPU_V7
1971 help
1972 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1973 Extension.
1974
1975config KERNEL_MODE_NEON
1976 bool "Support for NEON in kernel mode"
1977 depends on NEON && AEABI
1978 help
1979 Say Y to include support for NEON in kernel mode.
1980
1981endmenu
1982
1983menu "Power management options"
1984
1985source "kernel/power/Kconfig"
1986
1987config ARCH_SUSPEND_POSSIBLE
1988 depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
1989 CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
1990 def_bool y
1991
1992config ARM_CPU_SUSPEND
1993 def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
1994 depends on ARCH_SUSPEND_POSSIBLE
1995
1996config ARCH_HIBERNATION_POSSIBLE
1997 bool
1998 depends on MMU
1999 default y if ARCH_SUSPEND_POSSIBLE
2000
2001endmenu
2002
2003source "drivers/firmware/Kconfig"
2004
2005if CRYPTO
2006source "arch/arm/crypto/Kconfig"
2007endif
2008
2009source "arch/arm/Kconfig.assembler"