xref: /linux/arch/arm/Kconfig (revision c3848db316d51dcc0fb10554151b1e7e8ff8c3e2)
1# SPDX-License-Identifier: GPL-2.0
2config ARM
3	bool
4	default y
5	select ARCH_32BIT_OFF_T
6	select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE if HAVE_KRETPROBES && FRAME_POINTER && !ARM_UNWIND
7	select ARCH_HAS_BINFMT_FLAT
8	select ARCH_HAS_CURRENT_STACK_POINTER
9	select ARCH_HAS_DEBUG_VIRTUAL if MMU
10	select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE
11	select ARCH_HAS_ELF_RANDOMIZE
12	select ARCH_HAS_FORTIFY_SOURCE
13	select ARCH_HAS_KEEPINITRD
14	select ARCH_HAS_KCOV
15	select ARCH_HAS_MEMBARRIER_SYNC_CORE
16	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
17	select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
18	select ARCH_HAS_SETUP_DMA_OPS
19	select ARCH_HAS_SET_MEMORY
20	select ARCH_STACKWALK
21	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
22	select ARCH_HAS_STRICT_MODULE_RWX if MMU
23	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
24	select ARCH_HAS_SYNC_DMA_FOR_CPU
25	select ARCH_HAS_TEARDOWN_DMA_OPS if MMU
26	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
27	select ARCH_HAVE_CUSTOM_GPIO_H
28	select ARCH_HAVE_NMI_SAFE_CMPXCHG if CPU_V7 || CPU_V7M || CPU_V6K
29	select ARCH_HAS_GCOV_PROFILE_ALL
30	select ARCH_KEEP_MEMBLOCK
31	select ARCH_HAS_UBSAN_SANITIZE_ALL
32	select ARCH_MIGHT_HAVE_PC_PARPORT
33	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
34	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
35	select ARCH_SUPPORTS_ATOMIC_RMW
36	select ARCH_SUPPORTS_HUGETLBFS if ARM_LPAE
37	select ARCH_USE_BUILTIN_BSWAP
38	select ARCH_USE_CMPXCHG_LOCKREF
39	select ARCH_USE_MEMTEST
40	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
41	select ARCH_WANT_GENERAL_HUGETLB
42	select ARCH_WANT_IPC_PARSE_VERSION
43	select ARCH_WANT_LD_ORPHAN_WARN
44	select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
45	select BUILDTIME_TABLE_SORT if MMU
46	select COMMON_CLK if !(ARCH_RPC || ARCH_FOOTBRIDGE)
47	select CLONE_BACKWARDS
48	select CPU_PM if SUSPEND || CPU_IDLE
49	select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
50	select DMA_DECLARE_COHERENT
51	select DMA_GLOBAL_POOL if !MMU
52	select DMA_OPS
53	select DMA_NONCOHERENT_MMAP if MMU
54	select EDAC_SUPPORT
55	select EDAC_ATOMIC_SCRUB
56	select GENERIC_ALLOCATOR
57	select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
58	select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
59	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
60	select GENERIC_IRQ_IPI if SMP
61	select GENERIC_CPU_AUTOPROBE
62	select GENERIC_EARLY_IOREMAP
63	select GENERIC_IDLE_POLL_SETUP
64	select GENERIC_IRQ_MULTI_HANDLER
65	select GENERIC_IRQ_PROBE
66	select GENERIC_IRQ_SHOW
67	select GENERIC_IRQ_SHOW_LEVEL
68	select GENERIC_LIB_DEVMEM_IS_ALLOWED
69	select GENERIC_PCI_IOMAP
70	select GENERIC_SCHED_CLOCK
71	select GENERIC_SMP_IDLE_THREAD
72	select HARDIRQS_SW_RESEND
73	select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
74	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
75	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
76	select HAVE_ARCH_KFENCE if MMU && !XIP_KERNEL
77	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
78	select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
79	select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
80	select HAVE_ARCH_MMAP_RND_BITS if MMU
81	select HAVE_ARCH_PFN_VALID
82	select HAVE_ARCH_SECCOMP
83	select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT
84	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
85	select HAVE_ARCH_TRACEHOOK
86	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARM_LPAE
87	select HAVE_ARM_SMCCC if CPU_V7
88	select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
89	select HAVE_CONTEXT_TRACKING_USER
90	select HAVE_C_RECORDMCOUNT
91	select HAVE_BUILDTIME_MCOUNT_SORT
92	select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL
93	select HAVE_DMA_CONTIGUOUS if MMU
94	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
95	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
96	select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
97	select HAVE_EXIT_THREAD
98	select HAVE_FAST_GUP if ARM_LPAE
99	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
100	select HAVE_FUNCTION_ERROR_INJECTION
101	select HAVE_FUNCTION_GRAPH_TRACER
102	select HAVE_FUNCTION_TRACER if !XIP_KERNEL
103	select HAVE_GCC_PLUGINS
104	select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7)
105	select HAVE_IRQ_TIME_ACCOUNTING
106	select HAVE_KERNEL_GZIP
107	select HAVE_KERNEL_LZ4
108	select HAVE_KERNEL_LZMA
109	select HAVE_KERNEL_LZO
110	select HAVE_KERNEL_XZ
111	select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
112	select HAVE_KRETPROBES if HAVE_KPROBES
113	select HAVE_MOD_ARCH_SPECIFIC
114	select HAVE_NMI
115	select HAVE_OPTPROBES if !THUMB2_KERNEL
116	select HAVE_PCI if MMU
117	select HAVE_PERF_EVENTS
118	select HAVE_PERF_REGS
119	select HAVE_PERF_USER_STACK_DUMP
120	select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
121	select HAVE_REGS_AND_STACK_ACCESS_API
122	select HAVE_RSEQ
123	select HAVE_STACKPROTECTOR
124	select HAVE_SYSCALL_TRACEPOINTS
125	select HAVE_UID16
126	select HAVE_VIRT_CPU_ACCOUNTING_GEN
127	select IRQ_FORCED_THREADING
128	select MODULES_USE_ELF_REL
129	select NEED_DMA_MAP_STATE
130	select OF_EARLY_FLATTREE if OF
131	select OLD_SIGACTION
132	select OLD_SIGSUSPEND3
133	select PCI_DOMAINS_GENERIC if PCI
134	select PCI_SYSCALL if PCI
135	select PERF_USE_VMALLOC
136	select RTC_LIB
137	select SPARSE_IRQ if !(ARCH_FOOTBRIDGE || ARCH_RPC)
138	select SYS_SUPPORTS_APM_EMULATION
139	select THREAD_INFO_IN_TASK
140	select TIMER_OF if OF
141	select HAVE_ARCH_VMAP_STACK if MMU && ARM_HAS_GROUP_RELOCS
142	select TRACE_IRQFLAGS_SUPPORT if !CPU_V7M
143	select USE_OF if !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
144	# Above selects are sorted alphabetically; please add new ones
145	# according to that.  Thanks.
146	help
147	  The ARM series is a line of low-power-consumption RISC chip designs
148	  licensed by ARM Ltd and targeted at embedded applications and
149	  handhelds such as the Compaq IPAQ.  ARM-based PCs are no longer
150	  manufactured, but legacy ARM-based PC hardware remains popular in
151	  Europe.  There is an ARM Linux project with a web page at
152	  <http://www.arm.linux.org.uk/>.
153
154config ARM_HAS_GROUP_RELOCS
155	def_bool y
156	depends on !LD_IS_LLD || LLD_VERSION >= 140000
157	depends on !COMPILE_TEST
158	help
159	  Whether or not to use R_ARM_ALU_PC_Gn or R_ARM_LDR_PC_Gn group
160	  relocations, which have been around for a long time, but were not
161	  supported in LLD until version 14. The combined range is -/+ 256 MiB,
162	  which is usually sufficient, but not for allyesconfig, so we disable
163	  this feature when doing compile testing.
164
165config ARM_DMA_USE_IOMMU
166	bool
167	select NEED_SG_DMA_LENGTH
168
169if ARM_DMA_USE_IOMMU
170
171config ARM_DMA_IOMMU_ALIGNMENT
172	int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
173	range 4 9
174	default 8
175	help
176	  DMA mapping framework by default aligns all buffers to the smallest
177	  PAGE_SIZE order which is greater than or equal to the requested buffer
178	  size. This works well for buffers up to a few hundreds kilobytes, but
179	  for larger buffers it just a waste of address space. Drivers which has
180	  relatively small addressing window (like 64Mib) might run out of
181	  virtual space with just a few allocations.
182
183	  With this parameter you can specify the maximum PAGE_SIZE order for
184	  DMA IOMMU buffers. Larger buffers will be aligned only to this
185	  specified order. The order is expressed as a power of two multiplied
186	  by the PAGE_SIZE.
187
188endif
189
190config SYS_SUPPORTS_APM_EMULATION
191	bool
192
193config HAVE_TCM
194	bool
195	select GENERIC_ALLOCATOR
196
197config HAVE_PROC_CPU
198	bool
199
200config NO_IOPORT_MAP
201	bool
202
203config SBUS
204	bool
205
206config STACKTRACE_SUPPORT
207	bool
208	default y
209
210config LOCKDEP_SUPPORT
211	bool
212	default y
213
214config ARCH_HAS_ILOG2_U32
215	bool
216
217config ARCH_HAS_ILOG2_U64
218	bool
219
220config ARCH_HAS_BANDGAP
221	bool
222
223config FIX_EARLYCON_MEM
224	def_bool y if MMU
225
226config GENERIC_HWEIGHT
227	bool
228	default y
229
230config GENERIC_CALIBRATE_DELAY
231	bool
232	default y
233
234config ARCH_MAY_HAVE_PC_FDC
235	bool
236
237config ARCH_SUPPORTS_UPROBES
238	def_bool y
239
240config GENERIC_ISA_DMA
241	bool
242
243config FIQ
244	bool
245
246config ARCH_MTD_XIP
247	bool
248
249config ARM_PATCH_PHYS_VIRT
250	bool "Patch physical to virtual translations at runtime" if EMBEDDED
251	default y
252	depends on MMU
253	help
254	  Patch phys-to-virt and virt-to-phys translation functions at
255	  boot and module load time according to the position of the
256	  kernel in system memory.
257
258	  This can only be used with non-XIP MMU kernels where the base
259	  of physical memory is at a 2 MiB boundary.
260
261	  Only disable this option if you know that you do not require
262	  this feature (eg, building a kernel for a single machine) and
263	  you need to shrink the kernel to the minimal size.
264
265config NEED_MACH_IO_H
266	bool
267	help
268	  Select this when mach/io.h is required to provide special
269	  definitions for this platform.  The need for mach/io.h should
270	  be avoided when possible.
271
272config NEED_MACH_MEMORY_H
273	bool
274	help
275	  Select this when mach/memory.h is required to provide special
276	  definitions for this platform.  The need for mach/memory.h should
277	  be avoided when possible.
278
279config PHYS_OFFSET
280	hex "Physical address of main memory" if MMU
281	depends on !ARM_PATCH_PHYS_VIRT || !AUTO_ZRELADDR
282	default DRAM_BASE if !MMU
283	default 0x00000000 if ARCH_FOOTBRIDGE
284	default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
285	default 0x30000000 if ARCH_S3C24XX
286	default 0xa0000000 if ARCH_PXA
287	default 0xc0000000 if ARCH_EP93XX || ARCH_SA1100
288	default 0
289	help
290	  Please provide the physical address corresponding to the
291	  location of main memory in your system.
292
293config GENERIC_BUG
294	def_bool y
295	depends on BUG
296
297config PGTABLE_LEVELS
298	int
299	default 3 if ARM_LPAE
300	default 2
301
302menu "System Type"
303
304config MMU
305	bool "MMU-based Paged Memory Management Support"
306	default y
307	help
308	  Select if you want MMU-based virtualised addressing space
309	  support by paged memory management. If unsure, say 'Y'.
310
311config ARM_SINGLE_ARMV7M
312	def_bool !MMU
313	select ARM_NVIC
314	select CPU_V7M
315	select NO_IOPORT_MAP
316
317config ARCH_MMAP_RND_BITS_MIN
318	default 8
319
320config ARCH_MMAP_RND_BITS_MAX
321	default 14 if PAGE_OFFSET=0x40000000
322	default 15 if PAGE_OFFSET=0x80000000
323	default 16
324
325config ARCH_MULTIPLATFORM
326	bool "Require kernel to be portable to multiple machines" if EXPERT
327	depends on MMU && !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
328	default y
329	help
330	  In general, all Arm machines can be supported in a single
331	  kernel image, covering either Armv4/v5 or Armv6/v7.
332
333	  However, some configuration options require hardcoding machine
334	  specific physical addresses or enable errata workarounds that may
335	  break other machines.
336
337	  Selecting N here allows using those options, including
338	  DEBUG_UNCOMPRESS, XIP_KERNEL and ZBOOT_ROM. If unsure, say Y.
339
340menu "Platform selection"
341	depends on MMU
342
343comment "CPU Core family selection"
344
345config ARCH_MULTI_V4
346	bool "ARMv4 based platforms (FA526, StrongARM)"
347	depends on !ARCH_MULTI_V6_V7
348	depends on !LD_IS_LLD
349	select ARCH_MULTI_V4_V5
350	select CPU_FA526 if !(CPU_SA110 || CPU_SA1100)
351
352config ARCH_MULTI_V4T
353	bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
354	depends on !ARCH_MULTI_V6_V7
355	depends on !LD_IS_LLD
356	select ARCH_MULTI_V4_V5
357	select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
358		CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
359		CPU_ARM925T || CPU_ARM940T)
360
361config ARCH_MULTI_V5
362	bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
363	depends on !ARCH_MULTI_V6_V7
364	select ARCH_MULTI_V4_V5
365	select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
366		CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
367		CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
368
369config ARCH_MULTI_V4_V5
370	bool
371
372config ARCH_MULTI_V6
373	bool "ARMv6 based platforms (ARM11)"
374	select ARCH_MULTI_V6_V7
375	select CPU_V6K
376
377config ARCH_MULTI_V7
378	bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
379	default y
380	select ARCH_MULTI_V6_V7
381	select CPU_V7
382	select HAVE_SMP
383
384config ARCH_MULTI_V6_V7
385	bool
386	select MIGHT_HAVE_CACHE_L2X0
387
388config ARCH_MULTI_CPU_AUTO
389	def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
390	select ARCH_MULTI_V5
391
392endmenu
393
394config ARCH_VIRT
395	bool "Dummy Virtual Machine"
396	depends on ARCH_MULTI_V7
397	select ARM_AMBA
398	select ARM_GIC
399	select ARM_GIC_V2M if PCI
400	select ARM_GIC_V3
401	select ARM_GIC_V3_ITS if PCI
402	select ARM_PSCI
403	select HAVE_ARM_ARCH_TIMER
404
405config ARCH_AIROHA
406	bool "Airoha SoC Support"
407	depends on ARCH_MULTI_V7
408	select ARM_AMBA
409	select ARM_GIC
410	select ARM_GIC_V3
411	select ARM_PSCI
412	select HAVE_ARM_ARCH_TIMER
413	help
414	  Support for Airoha EN7523 SoCs
415
416#
417# This is sorted alphabetically by mach-* pathname.  However, plat-*
418# Kconfigs may be included either alphabetically (according to the
419# plat- suffix) or along side the corresponding mach-* source.
420#
421source "arch/arm/mach-actions/Kconfig"
422
423source "arch/arm/mach-alpine/Kconfig"
424
425source "arch/arm/mach-artpec/Kconfig"
426
427source "arch/arm/mach-asm9260/Kconfig"
428
429source "arch/arm/mach-aspeed/Kconfig"
430
431source "arch/arm/mach-at91/Kconfig"
432
433source "arch/arm/mach-axxia/Kconfig"
434
435source "arch/arm/mach-bcm/Kconfig"
436
437source "arch/arm/mach-berlin/Kconfig"
438
439source "arch/arm/mach-clps711x/Kconfig"
440
441source "arch/arm/mach-davinci/Kconfig"
442
443source "arch/arm/mach-digicolor/Kconfig"
444
445source "arch/arm/mach-dove/Kconfig"
446
447source "arch/arm/mach-ep93xx/Kconfig"
448
449source "arch/arm/mach-exynos/Kconfig"
450
451source "arch/arm/mach-footbridge/Kconfig"
452
453source "arch/arm/mach-gemini/Kconfig"
454
455source "arch/arm/mach-highbank/Kconfig"
456
457source "arch/arm/mach-hisi/Kconfig"
458
459source "arch/arm/mach-hpe/Kconfig"
460
461source "arch/arm/mach-imx/Kconfig"
462
463source "arch/arm/mach-ixp4xx/Kconfig"
464
465source "arch/arm/mach-keystone/Kconfig"
466
467source "arch/arm/mach-lpc32xx/Kconfig"
468
469source "arch/arm/mach-mediatek/Kconfig"
470
471source "arch/arm/mach-meson/Kconfig"
472
473source "arch/arm/mach-milbeaut/Kconfig"
474
475source "arch/arm/mach-mmp/Kconfig"
476
477source "arch/arm/mach-moxart/Kconfig"
478
479source "arch/arm/mach-mstar/Kconfig"
480
481source "arch/arm/mach-mv78xx0/Kconfig"
482
483source "arch/arm/mach-mvebu/Kconfig"
484
485source "arch/arm/mach-mxs/Kconfig"
486
487source "arch/arm/mach-nomadik/Kconfig"
488
489source "arch/arm/mach-npcm/Kconfig"
490
491source "arch/arm/mach-nspire/Kconfig"
492
493source "arch/arm/mach-omap1/Kconfig"
494
495source "arch/arm/mach-omap2/Kconfig"
496
497source "arch/arm/mach-orion5x/Kconfig"
498
499source "arch/arm/mach-oxnas/Kconfig"
500
501source "arch/arm/mach-pxa/Kconfig"
502
503source "arch/arm/mach-qcom/Kconfig"
504
505source "arch/arm/mach-rda/Kconfig"
506
507source "arch/arm/mach-realtek/Kconfig"
508
509source "arch/arm/mach-rpc/Kconfig"
510
511source "arch/arm/mach-rockchip/Kconfig"
512
513source "arch/arm/mach-s3c/Kconfig"
514
515source "arch/arm/mach-s5pv210/Kconfig"
516
517source "arch/arm/mach-sa1100/Kconfig"
518
519source "arch/arm/mach-shmobile/Kconfig"
520
521source "arch/arm/mach-socfpga/Kconfig"
522
523source "arch/arm/mach-spear/Kconfig"
524
525source "arch/arm/mach-sti/Kconfig"
526
527source "arch/arm/mach-stm32/Kconfig"
528
529source "arch/arm/mach-sunplus/Kconfig"
530
531source "arch/arm/mach-sunxi/Kconfig"
532
533source "arch/arm/mach-tegra/Kconfig"
534
535source "arch/arm/mach-uniphier/Kconfig"
536
537source "arch/arm/mach-ux500/Kconfig"
538
539source "arch/arm/mach-versatile/Kconfig"
540
541source "arch/arm/mach-vt8500/Kconfig"
542
543source "arch/arm/mach-zynq/Kconfig"
544
545# ARMv7-M architecture
546config ARCH_LPC18XX
547	bool "NXP LPC18xx/LPC43xx"
548	depends on ARM_SINGLE_ARMV7M
549	select ARCH_HAS_RESET_CONTROLLER
550	select ARM_AMBA
551	select CLKSRC_LPC32XX
552	select PINCTRL
553	help
554	  Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
555	  high performance microcontrollers.
556
557config ARCH_MPS2
558	bool "ARM MPS2 platform"
559	depends on ARM_SINGLE_ARMV7M
560	select ARM_AMBA
561	select CLKSRC_MPS2
562	help
563	  Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
564	  with a range of available cores like Cortex-M3/M4/M7.
565
566	  Please, note that depends which Application Note is used memory map
567	  for the platform may vary, so adjustment of RAM base might be needed.
568
569# Definitions to make life easier
570config ARCH_ACORN
571	bool
572
573config PLAT_ORION
574	bool
575	select CLKSRC_MMIO
576	select GENERIC_IRQ_CHIP
577	select IRQ_DOMAIN
578
579config PLAT_ORION_LEGACY
580	bool
581	select PLAT_ORION
582
583config PLAT_VERSATILE
584	bool
585
586source "arch/arm/mm/Kconfig"
587
588config IWMMXT
589	bool "Enable iWMMXt support"
590	depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
591	default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
592	help
593	  Enable support for iWMMXt context switching at run time if
594	  running on a CPU that supports it.
595
596if !MMU
597source "arch/arm/Kconfig-nommu"
598endif
599
600config PJ4B_ERRATA_4742
601	bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
602	depends on CPU_PJ4B && MACH_ARMADA_370
603	default y
604	help
605	  When coming out of either a Wait for Interrupt (WFI) or a Wait for
606	  Event (WFE) IDLE states, a specific timing sensitivity exists between
607	  the retiring WFI/WFE instructions and the newly issued subsequent
608	  instructions.  This sensitivity can result in a CPU hang scenario.
609	  Workaround:
610	  The software must insert either a Data Synchronization Barrier (DSB)
611	  or Data Memory Barrier (DMB) command immediately after the WFI/WFE
612	  instruction
613
614config ARM_ERRATA_326103
615	bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
616	depends on CPU_V6
617	help
618	  Executing a SWP instruction to read-only memory does not set bit 11
619	  of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
620	  treat the access as a read, preventing a COW from occurring and
621	  causing the faulting task to livelock.
622
623config ARM_ERRATA_411920
624	bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
625	depends on CPU_V6 || CPU_V6K
626	help
627	  Invalidation of the Instruction Cache operation can
628	  fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
629	  It does not affect the MPCore. This option enables the ARM Ltd.
630	  recommended workaround.
631
632config ARM_ERRATA_430973
633	bool "ARM errata: Stale prediction on replaced interworking branch"
634	depends on CPU_V7
635	help
636	  This option enables the workaround for the 430973 Cortex-A8
637	  r1p* erratum. If a code sequence containing an ARM/Thumb
638	  interworking branch is replaced with another code sequence at the
639	  same virtual address, whether due to self-modifying code or virtual
640	  to physical address re-mapping, Cortex-A8 does not recover from the
641	  stale interworking branch prediction. This results in Cortex-A8
642	  executing the new code sequence in the incorrect ARM or Thumb state.
643	  The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
644	  and also flushes the branch target cache at every context switch.
645	  Note that setting specific bits in the ACTLR register may not be
646	  available in non-secure mode.
647
648config ARM_ERRATA_458693
649	bool "ARM errata: Processor deadlock when a false hazard is created"
650	depends on CPU_V7
651	depends on !ARCH_MULTIPLATFORM
652	help
653	  This option enables the workaround for the 458693 Cortex-A8 (r2p0)
654	  erratum. For very specific sequences of memory operations, it is
655	  possible for a hazard condition intended for a cache line to instead
656	  be incorrectly associated with a different cache line. This false
657	  hazard might then cause a processor deadlock. The workaround enables
658	  the L1 caching of the NEON accesses and disables the PLD instruction
659	  in the ACTLR register. Note that setting specific bits in the ACTLR
660	  register may not be available in non-secure mode.
661
662config ARM_ERRATA_460075
663	bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
664	depends on CPU_V7
665	depends on !ARCH_MULTIPLATFORM
666	help
667	  This option enables the workaround for the 460075 Cortex-A8 (r2p0)
668	  erratum. Any asynchronous access to the L2 cache may encounter a
669	  situation in which recent store transactions to the L2 cache are lost
670	  and overwritten with stale memory contents from external memory. The
671	  workaround disables the write-allocate mode for the L2 cache via the
672	  ACTLR register. Note that setting specific bits in the ACTLR register
673	  may not be available in non-secure mode.
674
675config ARM_ERRATA_742230
676	bool "ARM errata: DMB operation may be faulty"
677	depends on CPU_V7 && SMP
678	depends on !ARCH_MULTIPLATFORM
679	help
680	  This option enables the workaround for the 742230 Cortex-A9
681	  (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
682	  between two write operations may not ensure the correct visibility
683	  ordering of the two writes. This workaround sets a specific bit in
684	  the diagnostic register of the Cortex-A9 which causes the DMB
685	  instruction to behave as a DSB, ensuring the correct behaviour of
686	  the two writes.
687
688config ARM_ERRATA_742231
689	bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
690	depends on CPU_V7 && SMP
691	depends on !ARCH_MULTIPLATFORM
692	help
693	  This option enables the workaround for the 742231 Cortex-A9
694	  (r2p0..r2p2) erratum. Under certain conditions, specific to the
695	  Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
696	  accessing some data located in the same cache line, may get corrupted
697	  data due to bad handling of the address hazard when the line gets
698	  replaced from one of the CPUs at the same time as another CPU is
699	  accessing it. This workaround sets specific bits in the diagnostic
700	  register of the Cortex-A9 which reduces the linefill issuing
701	  capabilities of the processor.
702
703config ARM_ERRATA_643719
704	bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
705	depends on CPU_V7 && SMP
706	default y
707	help
708	  This option enables the workaround for the 643719 Cortex-A9 (prior to
709	  r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
710	  register returns zero when it should return one. The workaround
711	  corrects this value, ensuring cache maintenance operations which use
712	  it behave as intended and avoiding data corruption.
713
714config ARM_ERRATA_720789
715	bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
716	depends on CPU_V7
717	help
718	  This option enables the workaround for the 720789 Cortex-A9 (prior to
719	  r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
720	  broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
721	  As a consequence of this erratum, some TLB entries which should be
722	  invalidated are not, resulting in an incoherency in the system page
723	  tables. The workaround changes the TLB flushing routines to invalidate
724	  entries regardless of the ASID.
725
726config ARM_ERRATA_743622
727	bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
728	depends on CPU_V7
729	depends on !ARCH_MULTIPLATFORM
730	help
731	  This option enables the workaround for the 743622 Cortex-A9
732	  (r2p*) erratum. Under very rare conditions, a faulty
733	  optimisation in the Cortex-A9 Store Buffer may lead to data
734	  corruption. This workaround sets a specific bit in the diagnostic
735	  register of the Cortex-A9 which disables the Store Buffer
736	  optimisation, preventing the defect from occurring. This has no
737	  visible impact on the overall performance or power consumption of the
738	  processor.
739
740config ARM_ERRATA_751472
741	bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
742	depends on CPU_V7
743	depends on !ARCH_MULTIPLATFORM
744	help
745	  This option enables the workaround for the 751472 Cortex-A9 (prior
746	  to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
747	  completion of a following broadcasted operation if the second
748	  operation is received by a CPU before the ICIALLUIS has completed,
749	  potentially leading to corrupted entries in the cache or TLB.
750
751config ARM_ERRATA_754322
752	bool "ARM errata: possible faulty MMU translations following an ASID switch"
753	depends on CPU_V7
754	help
755	  This option enables the workaround for the 754322 Cortex-A9 (r2p*,
756	  r3p*) erratum. A speculative memory access may cause a page table walk
757	  which starts prior to an ASID switch but completes afterwards. This
758	  can populate the micro-TLB with a stale entry which may be hit with
759	  the new ASID. This workaround places two dsb instructions in the mm
760	  switching code so that no page table walks can cross the ASID switch.
761
762config ARM_ERRATA_754327
763	bool "ARM errata: no automatic Store Buffer drain"
764	depends on CPU_V7 && SMP
765	help
766	  This option enables the workaround for the 754327 Cortex-A9 (prior to
767	  r2p0) erratum. The Store Buffer does not have any automatic draining
768	  mechanism and therefore a livelock may occur if an external agent
769	  continuously polls a memory location waiting to observe an update.
770	  This workaround defines cpu_relax() as smp_mb(), preventing correctly
771	  written polling loops from denying visibility of updates to memory.
772
773config ARM_ERRATA_364296
774	bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
775	depends on CPU_V6
776	help
777	  This options enables the workaround for the 364296 ARM1136
778	  r0p2 erratum (possible cache data corruption with
779	  hit-under-miss enabled). It sets the undocumented bit 31 in
780	  the auxiliary control register and the FI bit in the control
781	  register, thus disabling hit-under-miss without putting the
782	  processor into full low interrupt latency mode. ARM11MPCore
783	  is not affected.
784
785config ARM_ERRATA_764369
786	bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
787	depends on CPU_V7 && SMP
788	help
789	  This option enables the workaround for erratum 764369
790	  affecting Cortex-A9 MPCore with two or more processors (all
791	  current revisions). Under certain timing circumstances, a data
792	  cache line maintenance operation by MVA targeting an Inner
793	  Shareable memory region may fail to proceed up to either the
794	  Point of Coherency or to the Point of Unification of the
795	  system. This workaround adds a DSB instruction before the
796	  relevant cache maintenance functions and sets a specific bit
797	  in the diagnostic control register of the SCU.
798
799config ARM_ERRATA_764319
800	bool "ARM errata: Read to DBGPRSR and DBGOSLSR may generate Undefined instruction"
801	depends on CPU_V7
802	help
803	  This option enables the workaround for the 764319 Cortex A-9 erratum.
804	  CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
805	  unexpected Undefined Instruction exception when the DBGSWENABLE
806	  external pin is set to 0, even when the CP14 accesses are performed
807	  from a privileged mode. This work around catches the exception in a
808	  way the kernel does not stop execution.
809
810config ARM_ERRATA_775420
811       bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
812       depends on CPU_V7
813       help
814	 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
815	 r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
816	 operation aborts with MMU exception, it might cause the processor
817	 to deadlock. This workaround puts DSB before executing ISB if
818	 an abort may occur on cache maintenance.
819
820config ARM_ERRATA_798181
821	bool "ARM errata: TLBI/DSB failure on Cortex-A15"
822	depends on CPU_V7 && SMP
823	help
824	  On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
825	  adequately shooting down all use of the old entries. This
826	  option enables the Linux kernel workaround for this erratum
827	  which sends an IPI to the CPUs that are running the same ASID
828	  as the one being invalidated.
829
830config ARM_ERRATA_773022
831	bool "ARM errata: incorrect instructions may be executed from loop buffer"
832	depends on CPU_V7
833	help
834	  This option enables the workaround for the 773022 Cortex-A15
835	  (up to r0p4) erratum. In certain rare sequences of code, the
836	  loop buffer may deliver incorrect instructions. This
837	  workaround disables the loop buffer to avoid the erratum.
838
839config ARM_ERRATA_818325_852422
840	bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
841	depends on CPU_V7
842	help
843	  This option enables the workaround for:
844	  - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
845	    instruction might deadlock.  Fixed in r0p1.
846	  - Cortex-A12 852422: Execution of a sequence of instructions might
847	    lead to either a data corruption or a CPU deadlock.  Not fixed in
848	    any Cortex-A12 cores yet.
849	  This workaround for all both errata involves setting bit[12] of the
850	  Feature Register. This bit disables an optimisation applied to a
851	  sequence of 2 instructions that use opposing condition codes.
852
853config ARM_ERRATA_821420
854	bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
855	depends on CPU_V7
856	help
857	  This option enables the workaround for the 821420 Cortex-A12
858	  (all revs) erratum. In very rare timing conditions, a sequence
859	  of VMOV to Core registers instructions, for which the second
860	  one is in the shadow of a branch or abort, can lead to a
861	  deadlock when the VMOV instructions are issued out-of-order.
862
863config ARM_ERRATA_825619
864	bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
865	depends on CPU_V7
866	help
867	  This option enables the workaround for the 825619 Cortex-A12
868	  (all revs) erratum. Within rare timing constraints, executing a
869	  DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
870	  and Device/Strongly-Ordered loads and stores might cause deadlock
871
872config ARM_ERRATA_857271
873	bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
874	depends on CPU_V7
875	help
876	  This option enables the workaround for the 857271 Cortex-A12
877	  (all revs) erratum. Under very rare timing conditions, the CPU might
878	  hang. The workaround is expected to have a < 1% performance impact.
879
880config ARM_ERRATA_852421
881	bool "ARM errata: A17: DMB ST might fail to create order between stores"
882	depends on CPU_V7
883	help
884	  This option enables the workaround for the 852421 Cortex-A17
885	  (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
886	  execution of a DMB ST instruction might fail to properly order
887	  stores from GroupA and stores from GroupB.
888
889config ARM_ERRATA_852423
890	bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
891	depends on CPU_V7
892	help
893	  This option enables the workaround for:
894	  - Cortex-A17 852423: Execution of a sequence of instructions might
895	    lead to either a data corruption or a CPU deadlock.  Not fixed in
896	    any Cortex-A17 cores yet.
897	  This is identical to Cortex-A12 erratum 852422.  It is a separate
898	  config option from the A12 erratum due to the way errata are checked
899	  for and handled.
900
901config ARM_ERRATA_857272
902	bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
903	depends on CPU_V7
904	help
905	  This option enables the workaround for the 857272 Cortex-A17 erratum.
906	  This erratum is not known to be fixed in any A17 revision.
907	  This is identical to Cortex-A12 erratum 857271.  It is a separate
908	  config option from the A12 erratum due to the way errata are checked
909	  for and handled.
910
911endmenu
912
913source "arch/arm/common/Kconfig"
914
915menu "Bus support"
916
917config ISA
918	bool
919	help
920	  Find out whether you have ISA slots on your motherboard.  ISA is the
921	  name of a bus system, i.e. the way the CPU talks to the other stuff
922	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
923	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
924	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
925
926# Select ISA DMA interface
927config ISA_DMA_API
928	bool
929
930config PCI_NANOENGINE
931	bool "BSE nanoEngine PCI support"
932	depends on SA1100_NANOENGINE
933	help
934	  Enable PCI on the BSE nanoEngine board.
935
936config ARM_ERRATA_814220
937	bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
938	depends on CPU_V7
939	help
940	  The v7 ARM states that all cache and branch predictor maintenance
941	  operations that do not specify an address execute, relative to
942	  each other, in program order.
943	  However, because of this erratum, an L2 set/way cache maintenance
944	  operation can overtake an L1 set/way cache maintenance operation.
945	  This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
946	  r0p4, r0p5.
947
948endmenu
949
950menu "Kernel Features"
951
952config HAVE_SMP
953	bool
954	help
955	  This option should be selected by machines which have an SMP-
956	  capable CPU.
957
958	  The only effect of this option is to make the SMP-related
959	  options available to the user for configuration.
960
961config SMP
962	bool "Symmetric Multi-Processing"
963	depends on CPU_V6K || CPU_V7
964	depends on HAVE_SMP
965	depends on MMU || ARM_MPU
966	select IRQ_WORK
967	help
968	  This enables support for systems with more than one CPU. If you have
969	  a system with only one CPU, say N. If you have a system with more
970	  than one CPU, say Y.
971
972	  If you say N here, the kernel will run on uni- and multiprocessor
973	  machines, but will use only one CPU of a multiprocessor machine. If
974	  you say Y here, the kernel will run on many, but not all,
975	  uniprocessor machines. On a uniprocessor machine, the kernel
976	  will run faster if you say N here.
977
978	  See also <file:Documentation/x86/i386/IO-APIC.rst>,
979	  <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
980	  <http://tldp.org/HOWTO/SMP-HOWTO.html>.
981
982	  If you don't know what to do here, say N.
983
984config SMP_ON_UP
985	bool "Allow booting SMP kernel on uniprocessor systems"
986	depends on SMP && MMU
987	default y
988	help
989	  SMP kernels contain instructions which fail on non-SMP processors.
990	  Enabling this option allows the kernel to modify itself to make
991	  these instructions safe.  Disabling it allows about 1K of space
992	  savings.
993
994	  If you don't know what to do here, say Y.
995
996
997config CURRENT_POINTER_IN_TPIDRURO
998	def_bool y
999	depends on CPU_32v6K && !CPU_V6
1000
1001config IRQSTACKS
1002	def_bool y
1003	select HAVE_IRQ_EXIT_ON_IRQ_STACK
1004	select HAVE_SOFTIRQ_ON_OWN_STACK
1005
1006config ARM_CPU_TOPOLOGY
1007	bool "Support cpu topology definition"
1008	depends on SMP && CPU_V7
1009	default y
1010	help
1011	  Support ARM cpu topology definition. The MPIDR register defines
1012	  affinity between processors which is then used to describe the cpu
1013	  topology of an ARM System.
1014
1015config SCHED_MC
1016	bool "Multi-core scheduler support"
1017	depends on ARM_CPU_TOPOLOGY
1018	help
1019	  Multi-core scheduler support improves the CPU scheduler's decision
1020	  making when dealing with multi-core CPU chips at a cost of slightly
1021	  increased overhead in some places. If unsure say N here.
1022
1023config SCHED_SMT
1024	bool "SMT scheduler support"
1025	depends on ARM_CPU_TOPOLOGY
1026	help
1027	  Improves the CPU scheduler's decision making when dealing with
1028	  MultiThreading at a cost of slightly increased overhead in some
1029	  places. If unsure say N here.
1030
1031config HAVE_ARM_SCU
1032	bool
1033	help
1034	  This option enables support for the ARM snoop control unit
1035
1036config HAVE_ARM_ARCH_TIMER
1037	bool "Architected timer support"
1038	depends on CPU_V7
1039	select ARM_ARCH_TIMER
1040	help
1041	  This option enables support for the ARM architected timer
1042
1043config HAVE_ARM_TWD
1044	bool
1045	help
1046	  This options enables support for the ARM timer and watchdog unit
1047
1048config MCPM
1049	bool "Multi-Cluster Power Management"
1050	depends on CPU_V7 && SMP
1051	help
1052	  This option provides the common power management infrastructure
1053	  for (multi-)cluster based systems, such as big.LITTLE based
1054	  systems.
1055
1056config MCPM_QUAD_CLUSTER
1057	bool
1058	depends on MCPM
1059	help
1060	  To avoid wasting resources unnecessarily, MCPM only supports up
1061	  to 2 clusters by default.
1062	  Platforms with 3 or 4 clusters that use MCPM must select this
1063	  option to allow the additional clusters to be managed.
1064
1065config BIG_LITTLE
1066	bool "big.LITTLE support (Experimental)"
1067	depends on CPU_V7 && SMP
1068	select MCPM
1069	help
1070	  This option enables support selections for the big.LITTLE
1071	  system architecture.
1072
1073config BL_SWITCHER
1074	bool "big.LITTLE switcher support"
1075	depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
1076	select CPU_PM
1077	help
1078	  The big.LITTLE "switcher" provides the core functionality to
1079	  transparently handle transition between a cluster of A15's
1080	  and a cluster of A7's in a big.LITTLE system.
1081
1082config BL_SWITCHER_DUMMY_IF
1083	tristate "Simple big.LITTLE switcher user interface"
1084	depends on BL_SWITCHER && DEBUG_KERNEL
1085	help
1086	  This is a simple and dummy char dev interface to control
1087	  the big.LITTLE switcher core code.  It is meant for
1088	  debugging purposes only.
1089
1090choice
1091	prompt "Memory split"
1092	depends on MMU
1093	default VMSPLIT_3G
1094	help
1095	  Select the desired split between kernel and user memory.
1096
1097	  If you are not absolutely sure what you are doing, leave this
1098	  option alone!
1099
1100	config VMSPLIT_3G
1101		bool "3G/1G user/kernel split"
1102	config VMSPLIT_3G_OPT
1103		depends on !ARM_LPAE
1104		bool "3G/1G user/kernel split (for full 1G low memory)"
1105	config VMSPLIT_2G
1106		bool "2G/2G user/kernel split"
1107	config VMSPLIT_1G
1108		bool "1G/3G user/kernel split"
1109endchoice
1110
1111config PAGE_OFFSET
1112	hex
1113	default PHYS_OFFSET if !MMU
1114	default 0x40000000 if VMSPLIT_1G
1115	default 0x80000000 if VMSPLIT_2G
1116	default 0xB0000000 if VMSPLIT_3G_OPT
1117	default 0xC0000000
1118
1119config KASAN_SHADOW_OFFSET
1120	hex
1121	depends on KASAN
1122	default 0x1f000000 if PAGE_OFFSET=0x40000000
1123	default 0x5f000000 if PAGE_OFFSET=0x80000000
1124	default 0x9f000000 if PAGE_OFFSET=0xC0000000
1125	default 0x8f000000 if PAGE_OFFSET=0xB0000000
1126	default 0xffffffff
1127
1128config NR_CPUS
1129	int "Maximum number of CPUs (2-32)"
1130	range 2 16 if DEBUG_KMAP_LOCAL
1131	range 2 32 if !DEBUG_KMAP_LOCAL
1132	depends on SMP
1133	default "4"
1134	help
1135	  The maximum number of CPUs that the kernel can support.
1136	  Up to 32 CPUs can be supported, or up to 16 if kmap_local()
1137	  debugging is enabled, which uses half of the per-CPU fixmap
1138	  slots as guard regions.
1139
1140config HOTPLUG_CPU
1141	bool "Support for hot-pluggable CPUs"
1142	depends on SMP
1143	select GENERIC_IRQ_MIGRATION
1144	help
1145	  Say Y here to experiment with turning CPUs off and on.  CPUs
1146	  can be controlled through /sys/devices/system/cpu.
1147
1148config ARM_PSCI
1149	bool "Support for the ARM Power State Coordination Interface (PSCI)"
1150	depends on HAVE_ARM_SMCCC
1151	select ARM_PSCI_FW
1152	help
1153	  Say Y here if you want Linux to communicate with system firmware
1154	  implementing the PSCI specification for CPU-centric power
1155	  management operations described in ARM document number ARM DEN
1156	  0022A ("Power State Coordination Interface System Software on
1157	  ARM processors").
1158
1159config HZ_FIXED
1160	int
1161	default 128 if SOC_AT91RM9200
1162	default 0
1163
1164choice
1165	depends on HZ_FIXED = 0
1166	prompt "Timer frequency"
1167
1168config HZ_100
1169	bool "100 Hz"
1170
1171config HZ_200
1172	bool "200 Hz"
1173
1174config HZ_250
1175	bool "250 Hz"
1176
1177config HZ_300
1178	bool "300 Hz"
1179
1180config HZ_500
1181	bool "500 Hz"
1182
1183config HZ_1000
1184	bool "1000 Hz"
1185
1186endchoice
1187
1188config HZ
1189	int
1190	default HZ_FIXED if HZ_FIXED != 0
1191	default 100 if HZ_100
1192	default 200 if HZ_200
1193	default 250 if HZ_250
1194	default 300 if HZ_300
1195	default 500 if HZ_500
1196	default 1000
1197
1198config SCHED_HRTICK
1199	def_bool HIGH_RES_TIMERS
1200
1201config THUMB2_KERNEL
1202	bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1203	depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1204	default y if CPU_THUMBONLY
1205	select ARM_UNWIND
1206	help
1207	  By enabling this option, the kernel will be compiled in
1208	  Thumb-2 mode.
1209
1210	  If unsure, say N.
1211
1212config ARM_PATCH_IDIV
1213	bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
1214	depends on CPU_32v7
1215	default y
1216	help
1217	  The ARM compiler inserts calls to __aeabi_idiv() and
1218	  __aeabi_uidiv() when it needs to perform division on signed
1219	  and unsigned integers. Some v7 CPUs have support for the sdiv
1220	  and udiv instructions that can be used to implement those
1221	  functions.
1222
1223	  Enabling this option allows the kernel to modify itself to
1224	  replace the first two instructions of these library functions
1225	  with the sdiv or udiv plus "bx lr" instructions when the CPU
1226	  it is running on supports them. Typically this will be faster
1227	  and less power intensive than running the original library
1228	  code to do integer division.
1229
1230config AEABI
1231	bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1232		!CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1233	default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
1234	help
1235	  This option allows for the kernel to be compiled using the latest
1236	  ARM ABI (aka EABI).  This is only useful if you are using a user
1237	  space environment that is also compiled with EABI.
1238
1239	  Since there are major incompatibilities between the legacy ABI and
1240	  EABI, especially with regard to structure member alignment, this
1241	  option also changes the kernel syscall calling convention to
1242	  disambiguate both ABIs and allow for backward compatibility support
1243	  (selected with CONFIG_OABI_COMPAT).
1244
1245	  To use this you need GCC version 4.0.0 or later.
1246
1247config OABI_COMPAT
1248	bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1249	depends on AEABI && !THUMB2_KERNEL
1250	help
1251	  This option preserves the old syscall interface along with the
1252	  new (ARM EABI) one. It also provides a compatibility layer to
1253	  intercept syscalls that have structure arguments which layout
1254	  in memory differs between the legacy ABI and the new ARM EABI
1255	  (only for non "thumb" binaries). This option adds a tiny
1256	  overhead to all syscalls and produces a slightly larger kernel.
1257
1258	  The seccomp filter system will not be available when this is
1259	  selected, since there is no way yet to sensibly distinguish
1260	  between calling conventions during filtering.
1261
1262	  If you know you'll be using only pure EABI user space then you
1263	  can say N here. If this option is not selected and you attempt
1264	  to execute a legacy ABI binary then the result will be
1265	  UNPREDICTABLE (in fact it can be predicted that it won't work
1266	  at all). If in doubt say N.
1267
1268config ARCH_SELECT_MEMORY_MODEL
1269	def_bool y
1270
1271config ARCH_FLATMEM_ENABLE
1272	def_bool !(ARCH_RPC || ARCH_SA1100)
1273
1274config ARCH_SPARSEMEM_ENABLE
1275	def_bool !ARCH_FOOTBRIDGE
1276	select SPARSEMEM_STATIC if SPARSEMEM
1277
1278config HIGHMEM
1279	bool "High Memory Support"
1280	depends on MMU
1281	select KMAP_LOCAL
1282	select KMAP_LOCAL_NON_LINEAR_PTE_ARRAY
1283	help
1284	  The address space of ARM processors is only 4 Gigabytes large
1285	  and it has to accommodate user address space, kernel address
1286	  space as well as some memory mapped IO. That means that, if you
1287	  have a large amount of physical memory and/or IO, not all of the
1288	  memory can be "permanently mapped" by the kernel. The physical
1289	  memory that is not permanently mapped is called "high memory".
1290
1291	  Depending on the selected kernel/user memory split, minimum
1292	  vmalloc space and actual amount of RAM, you may not need this
1293	  option which should result in a slightly faster kernel.
1294
1295	  If unsure, say n.
1296
1297config HIGHPTE
1298	bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1299	depends on HIGHMEM
1300	default y
1301	help
1302	  The VM uses one page of physical memory for each page table.
1303	  For systems with a lot of processes, this can use a lot of
1304	  precious low memory, eventually leading to low memory being
1305	  consumed by page tables.  Setting this option will allow
1306	  user-space 2nd level page tables to reside in high memory.
1307
1308config CPU_SW_DOMAIN_PAN
1309	bool "Enable use of CPU domains to implement privileged no-access"
1310	depends on MMU && !ARM_LPAE
1311	default y
1312	help
1313	  Increase kernel security by ensuring that normal kernel accesses
1314	  are unable to access userspace addresses.  This can help prevent
1315	  use-after-free bugs becoming an exploitable privilege escalation
1316	  by ensuring that magic values (such as LIST_POISON) will always
1317	  fault when dereferenced.
1318
1319	  CPUs with low-vector mappings use a best-efforts implementation.
1320	  Their lower 1MB needs to remain accessible for the vectors, but
1321	  the remainder of userspace will become appropriately inaccessible.
1322
1323config HW_PERF_EVENTS
1324	def_bool y
1325	depends on ARM_PMU
1326
1327config ARM_MODULE_PLTS
1328	bool "Use PLTs to allow module memory to spill over into vmalloc area"
1329	depends on MODULES
1330	select KASAN_VMALLOC if KASAN
1331	default y
1332	help
1333	  Allocate PLTs when loading modules so that jumps and calls whose
1334	  targets are too far away for their relative offsets to be encoded
1335	  in the instructions themselves can be bounced via veneers in the
1336	  module's PLT. This allows modules to be allocated in the generic
1337	  vmalloc area after the dedicated module memory area has been
1338	  exhausted. The modules will use slightly more memory, but after
1339	  rounding up to page size, the actual memory footprint is usually
1340	  the same.
1341
1342	  Disabling this is usually safe for small single-platform
1343	  configurations. If unsure, say y.
1344
1345config ARCH_FORCE_MAX_ORDER
1346	int "Maximum zone order"
1347	default "12" if SOC_AM33XX
1348	default "9" if SA1111
1349	default "11"
1350	help
1351	  The kernel memory allocator divides physically contiguous memory
1352	  blocks into "zones", where each zone is a power of two number of
1353	  pages.  This option selects the largest power of two that the kernel
1354	  keeps in the memory allocator.  If you need to allocate very large
1355	  blocks of physically contiguous memory, then you may need to
1356	  increase this value.
1357
1358	  This config option is actually maximum order plus one. For example,
1359	  a value of 11 means that the largest free memory block is 2^10 pages.
1360
1361config ALIGNMENT_TRAP
1362	def_bool CPU_CP15_MMU
1363	select HAVE_PROC_CPU if PROC_FS
1364	help
1365	  ARM processors cannot fetch/store information which is not
1366	  naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1367	  address divisible by 4. On 32-bit ARM processors, these non-aligned
1368	  fetch/store instructions will be emulated in software if you say
1369	  here, which has a severe performance impact. This is necessary for
1370	  correct operation of some network protocols. With an IP-only
1371	  configuration it is safe to say N, otherwise say Y.
1372
1373config UACCESS_WITH_MEMCPY
1374	bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1375	depends on MMU
1376	default y if CPU_FEROCEON
1377	help
1378	  Implement faster copy_to_user and clear_user methods for CPU
1379	  cores where a 8-word STM instruction give significantly higher
1380	  memory write throughput than a sequence of individual 32bit stores.
1381
1382	  A possible side effect is a slight increase in scheduling latency
1383	  between threads sharing the same address space if they invoke
1384	  such copy operations with large buffers.
1385
1386	  However, if the CPU data cache is using a write-allocate mode,
1387	  this option is unlikely to provide any performance gain.
1388
1389config PARAVIRT
1390	bool "Enable paravirtualization code"
1391	help
1392	  This changes the kernel so it can modify itself when it is run
1393	  under a hypervisor, potentially improving performance significantly
1394	  over full virtualization.
1395
1396config PARAVIRT_TIME_ACCOUNTING
1397	bool "Paravirtual steal time accounting"
1398	select PARAVIRT
1399	help
1400	  Select this option to enable fine granularity task steal time
1401	  accounting. Time spent executing other tasks in parallel with
1402	  the current vCPU is discounted from the vCPU power. To account for
1403	  that, there can be a small performance impact.
1404
1405	  If in doubt, say N here.
1406
1407config XEN_DOM0
1408	def_bool y
1409	depends on XEN
1410
1411config XEN
1412	bool "Xen guest support on ARM"
1413	depends on ARM && AEABI && OF
1414	depends on CPU_V7 && !CPU_V6
1415	depends on !GENERIC_ATOMIC64
1416	depends on MMU
1417	select ARCH_DMA_ADDR_T_64BIT
1418	select ARM_PSCI
1419	select SWIOTLB
1420	select SWIOTLB_XEN
1421	select PARAVIRT
1422	help
1423	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1424
1425config CC_HAVE_STACKPROTECTOR_TLS
1426	def_bool $(cc-option,-mtp=cp15 -mstack-protector-guard=tls -mstack-protector-guard-offset=0)
1427
1428config STACKPROTECTOR_PER_TASK
1429	bool "Use a unique stack canary value for each task"
1430	depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA
1431	depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS
1432	select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS
1433	default y
1434	help
1435	  Due to the fact that GCC uses an ordinary symbol reference from
1436	  which to load the value of the stack canary, this value can only
1437	  change at reboot time on SMP systems, and all tasks running in the
1438	  kernel's address space are forced to use the same canary value for
1439	  the entire duration that the system is up.
1440
1441	  Enable this option to switch to a different method that uses a
1442	  different canary value for each task.
1443
1444endmenu
1445
1446menu "Boot options"
1447
1448config USE_OF
1449	bool "Flattened Device Tree support"
1450	select IRQ_DOMAIN
1451	select OF
1452	help
1453	  Include support for flattened device tree machine descriptions.
1454
1455config ATAGS
1456	bool "Support for the traditional ATAGS boot data passing"
1457	default y
1458	help
1459	  This is the traditional way of passing data to the kernel at boot
1460	  time. If you are solely relying on the flattened device tree (or
1461	  the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1462	  to remove ATAGS support from your kernel binary.
1463
1464config UNUSED_BOARD_FILES
1465	bool "Board support for machines without known users"
1466	depends on ATAGS
1467	help
1468	  Most ATAGS based board files are completely unused and are
1469	  scheduled for removal in early 2023, and left out of kernels
1470	  by default now.  If you are using a board file that is marked
1471	  as unused, turn on this option to build support into the kernel.
1472
1473	  To keep support for your individual board from being removed,
1474	  send a reply to the email discussion at
1475	  https://lore.kernel.org/all/CAK8P3a0Z9vGEQbVRBo84bSyPFM-LF+hs5w8ZA51g2Z+NsdtDQA@mail.gmail.com/
1476
1477config DEPRECATED_PARAM_STRUCT
1478	bool "Provide old way to pass kernel parameters"
1479	depends on ATAGS
1480	help
1481	  This was deprecated in 2001 and announced to live on for 5 years.
1482	  Some old boot loaders still use this way.
1483
1484# Compressed boot loader in ROM.  Yes, we really want to ask about
1485# TEXT and BSS so we preserve their values in the config files.
1486config ZBOOT_ROM_TEXT
1487	hex "Compressed ROM boot loader base address"
1488	default 0x0
1489	help
1490	  The physical address at which the ROM-able zImage is to be
1491	  placed in the target.  Platforms which normally make use of
1492	  ROM-able zImage formats normally set this to a suitable
1493	  value in their defconfig file.
1494
1495	  If ZBOOT_ROM is not enabled, this has no effect.
1496
1497config ZBOOT_ROM_BSS
1498	hex "Compressed ROM boot loader BSS address"
1499	default 0x0
1500	help
1501	  The base address of an area of read/write memory in the target
1502	  for the ROM-able zImage which must be available while the
1503	  decompressor is running. It must be large enough to hold the
1504	  entire decompressed kernel plus an additional 128 KiB.
1505	  Platforms which normally make use of ROM-able zImage formats
1506	  normally set this to a suitable value in their defconfig file.
1507
1508	  If ZBOOT_ROM is not enabled, this has no effect.
1509
1510config ZBOOT_ROM
1511	bool "Compressed boot loader in ROM/flash"
1512	depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1513	depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1514	help
1515	  Say Y here if you intend to execute your compressed kernel image
1516	  (zImage) directly from ROM or flash.  If unsure, say N.
1517
1518config ARM_APPENDED_DTB
1519	bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1520	depends on OF
1521	help
1522	  With this option, the boot code will look for a device tree binary
1523	  (DTB) appended to zImage
1524	  (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1525
1526	  This is meant as a backward compatibility convenience for those
1527	  systems with a bootloader that can't be upgraded to accommodate
1528	  the documented boot protocol using a device tree.
1529
1530	  Beware that there is very little in terms of protection against
1531	  this option being confused by leftover garbage in memory that might
1532	  look like a DTB header after a reboot if no actual DTB is appended
1533	  to zImage.  Do not leave this option active in a production kernel
1534	  if you don't intend to always append a DTB.  Proper passing of the
1535	  location into r2 of a bootloader provided DTB is always preferable
1536	  to this option.
1537
1538config ARM_ATAG_DTB_COMPAT
1539	bool "Supplement the appended DTB with traditional ATAG information"
1540	depends on ARM_APPENDED_DTB
1541	help
1542	  Some old bootloaders can't be updated to a DTB capable one, yet
1543	  they provide ATAGs with memory configuration, the ramdisk address,
1544	  the kernel cmdline string, etc.  Such information is dynamically
1545	  provided by the bootloader and can't always be stored in a static
1546	  DTB.  To allow a device tree enabled kernel to be used with such
1547	  bootloaders, this option allows zImage to extract the information
1548	  from the ATAG list and store it at run time into the appended DTB.
1549
1550choice
1551	prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1552	default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1553
1554config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1555	bool "Use bootloader kernel arguments if available"
1556	help
1557	  Uses the command-line options passed by the boot loader instead of
1558	  the device tree bootargs property. If the boot loader doesn't provide
1559	  any, the device tree bootargs property will be used.
1560
1561config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1562	bool "Extend with bootloader kernel arguments"
1563	help
1564	  The command-line arguments provided by the boot loader will be
1565	  appended to the the device tree bootargs property.
1566
1567endchoice
1568
1569config CMDLINE
1570	string "Default kernel command string"
1571	default ""
1572	help
1573	  On some architectures (e.g. CATS), there is currently no way
1574	  for the boot loader to pass arguments to the kernel. For these
1575	  architectures, you should supply some command-line options at build
1576	  time by entering them here. As a minimum, you should specify the
1577	  memory size and the root device (e.g., mem=64M root=/dev/nfs).
1578
1579choice
1580	prompt "Kernel command line type" if CMDLINE != ""
1581	default CMDLINE_FROM_BOOTLOADER
1582
1583config CMDLINE_FROM_BOOTLOADER
1584	bool "Use bootloader kernel arguments if available"
1585	help
1586	  Uses the command-line options passed by the boot loader. If
1587	  the boot loader doesn't provide any, the default kernel command
1588	  string provided in CMDLINE will be used.
1589
1590config CMDLINE_EXTEND
1591	bool "Extend bootloader kernel arguments"
1592	help
1593	  The command-line arguments provided by the boot loader will be
1594	  appended to the default kernel command string.
1595
1596config CMDLINE_FORCE
1597	bool "Always use the default kernel command string"
1598	help
1599	  Always use the default kernel command string, even if the boot
1600	  loader passes other arguments to the kernel.
1601	  This is useful if you cannot or don't want to change the
1602	  command-line options your boot loader passes to the kernel.
1603endchoice
1604
1605config XIP_KERNEL
1606	bool "Kernel Execute-In-Place from ROM"
1607	depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
1608	depends on !ARM_PATCH_IDIV && !ARM_PATCH_PHYS_VIRT && !SMP_ON_UP
1609	help
1610	  Execute-In-Place allows the kernel to run from non-volatile storage
1611	  directly addressable by the CPU, such as NOR flash. This saves RAM
1612	  space since the text section of the kernel is not loaded from flash
1613	  to RAM.  Read-write sections, such as the data section and stack,
1614	  are still copied to RAM.  The XIP kernel is not compressed since
1615	  it has to run directly from flash, so it will take more space to
1616	  store it.  The flash address used to link the kernel object files,
1617	  and for storing it, is configuration dependent. Therefore, if you
1618	  say Y here, you must know the proper physical address where to
1619	  store the kernel image depending on your own flash memory usage.
1620
1621	  Also note that the make target becomes "make xipImage" rather than
1622	  "make zImage" or "make Image".  The final kernel binary to put in
1623	  ROM memory will be arch/arm/boot/xipImage.
1624
1625	  If unsure, say N.
1626
1627config XIP_PHYS_ADDR
1628	hex "XIP Kernel Physical Location"
1629	depends on XIP_KERNEL
1630	default "0x00080000"
1631	help
1632	  This is the physical address in your flash memory the kernel will
1633	  be linked for and stored to.  This address is dependent on your
1634	  own flash usage.
1635
1636config XIP_DEFLATED_DATA
1637	bool "Store kernel .data section compressed in ROM"
1638	depends on XIP_KERNEL
1639	select ZLIB_INFLATE
1640	help
1641	  Before the kernel is actually executed, its .data section has to be
1642	  copied to RAM from ROM. This option allows for storing that data
1643	  in compressed form and decompressed to RAM rather than merely being
1644	  copied, saving some precious ROM space. A possible drawback is a
1645	  slightly longer boot delay.
1646
1647config KEXEC
1648	bool "Kexec system call (EXPERIMENTAL)"
1649	depends on (!SMP || PM_SLEEP_SMP)
1650	depends on MMU
1651	select KEXEC_CORE
1652	help
1653	  kexec is a system call that implements the ability to shutdown your
1654	  current kernel, and to start another kernel.  It is like a reboot
1655	  but it is independent of the system firmware.   And like a reboot
1656	  you can start any kernel with it, not just Linux.
1657
1658	  It is an ongoing process to be certain the hardware in a machine
1659	  is properly shutdown, so do not be surprised if this code does not
1660	  initially work for you.
1661
1662config ATAGS_PROC
1663	bool "Export atags in procfs"
1664	depends on ATAGS && KEXEC
1665	default y
1666	help
1667	  Should the atags used to boot the kernel be exported in an "atags"
1668	  file in procfs. Useful with kexec.
1669
1670config CRASH_DUMP
1671	bool "Build kdump crash kernel (EXPERIMENTAL)"
1672	help
1673	  Generate crash dump after being started by kexec. This should
1674	  be normally only set in special crash dump kernels which are
1675	  loaded in the main kernel with kexec-tools into a specially
1676	  reserved region and then later executed after a crash by
1677	  kdump/kexec. The crash dump kernel must be compiled to a
1678	  memory address not used by the main kernel
1679
1680	  For more details see Documentation/admin-guide/kdump/kdump.rst
1681
1682config AUTO_ZRELADDR
1683	bool "Auto calculation of the decompressed kernel image address" if !ARCH_MULTIPLATFORM
1684	default !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
1685	help
1686	  ZRELADDR is the physical address where the decompressed kernel
1687	  image will be placed. If AUTO_ZRELADDR is selected, the address
1688	  will be determined at run-time, either by masking the current IP
1689	  with 0xf8000000, or, if invalid, from the DTB passed in r2.
1690	  This assumes the zImage being placed in the first 128MB from
1691	  start of memory.
1692
1693config EFI_STUB
1694	bool
1695
1696config EFI
1697	bool "UEFI runtime support"
1698	depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
1699	select UCS2_STRING
1700	select EFI_PARAMS_FROM_FDT
1701	select EFI_STUB
1702	select EFI_GENERIC_STUB
1703	select EFI_RUNTIME_WRAPPERS
1704	help
1705	  This option provides support for runtime services provided
1706	  by UEFI firmware (such as non-volatile variables, realtime
1707	  clock, and platform reset). A UEFI stub is also provided to
1708	  allow the kernel to be booted as an EFI application. This
1709	  is only useful for kernels that may run on systems that have
1710	  UEFI firmware.
1711
1712config DMI
1713	bool "Enable support for SMBIOS (DMI) tables"
1714	depends on EFI
1715	default y
1716	help
1717	  This enables SMBIOS/DMI feature for systems.
1718
1719	  This option is only useful on systems that have UEFI firmware.
1720	  However, even with this option, the resultant kernel should
1721	  continue to boot on existing non-UEFI platforms.
1722
1723	  NOTE: This does *NOT* enable or encourage the use of DMI quirks,
1724	  i.e., the the practice of identifying the platform via DMI to
1725	  decide whether certain workarounds for buggy hardware and/or
1726	  firmware need to be enabled. This would require the DMI subsystem
1727	  to be enabled much earlier than we do on ARM, which is non-trivial.
1728
1729endmenu
1730
1731menu "CPU Power Management"
1732
1733source "drivers/cpufreq/Kconfig"
1734
1735source "drivers/cpuidle/Kconfig"
1736
1737endmenu
1738
1739menu "Floating point emulation"
1740
1741comment "At least one emulation must be selected"
1742
1743config FPE_NWFPE
1744	bool "NWFPE math emulation"
1745	depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
1746	help
1747	  Say Y to include the NWFPE floating point emulator in the kernel.
1748	  This is necessary to run most binaries. Linux does not currently
1749	  support floating point hardware so you need to say Y here even if
1750	  your machine has an FPA or floating point co-processor podule.
1751
1752	  You may say N here if you are going to load the Acorn FPEmulator
1753	  early in the bootup.
1754
1755config FPE_NWFPE_XP
1756	bool "Support extended precision"
1757	depends on FPE_NWFPE
1758	help
1759	  Say Y to include 80-bit support in the kernel floating-point
1760	  emulator.  Otherwise, only 32 and 64-bit support is compiled in.
1761	  Note that gcc does not generate 80-bit operations by default,
1762	  so in most cases this option only enlarges the size of the
1763	  floating point emulator without any good reason.
1764
1765	  You almost surely want to say N here.
1766
1767config FPE_FASTFPE
1768	bool "FastFPE math emulation (EXPERIMENTAL)"
1769	depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
1770	help
1771	  Say Y here to include the FAST floating point emulator in the kernel.
1772	  This is an experimental much faster emulator which now also has full
1773	  precision for the mantissa.  It does not support any exceptions.
1774	  It is very simple, and approximately 3-6 times faster than NWFPE.
1775
1776	  It should be sufficient for most programs.  It may be not suitable
1777	  for scientific calculations, but you have to check this for yourself.
1778	  If you do not feel you need a faster FP emulation you should better
1779	  choose NWFPE.
1780
1781config VFP
1782	bool "VFP-format floating point maths"
1783	depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1784	help
1785	  Say Y to include VFP support code in the kernel. This is needed
1786	  if your hardware includes a VFP unit.
1787
1788	  Please see <file:Documentation/arm/vfp/release-notes.rst> for
1789	  release notes and additional status information.
1790
1791	  Say N if your target does not have VFP hardware.
1792
1793config VFPv3
1794	bool
1795	depends on VFP
1796	default y if CPU_V7
1797
1798config NEON
1799	bool "Advanced SIMD (NEON) Extension support"
1800	depends on VFPv3 && CPU_V7
1801	help
1802	  Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1803	  Extension.
1804
1805config KERNEL_MODE_NEON
1806	bool "Support for NEON in kernel mode"
1807	depends on NEON && AEABI
1808	help
1809	  Say Y to include support for NEON in kernel mode.
1810
1811endmenu
1812
1813menu "Power management options"
1814
1815source "kernel/power/Kconfig"
1816
1817config ARCH_SUSPEND_POSSIBLE
1818	depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
1819		CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
1820	def_bool y
1821
1822config ARM_CPU_SUSPEND
1823	def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
1824	depends on ARCH_SUSPEND_POSSIBLE
1825
1826config ARCH_HIBERNATION_POSSIBLE
1827	bool
1828	depends on MMU
1829	default y if ARCH_SUSPEND_POSSIBLE
1830
1831endmenu
1832
1833source "arch/arm/Kconfig.assembler"
1834