xref: /linux/arch/arm/Kconfig (revision 09e61efd884ca68a768717d60858f138685b161b)
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_IOP32X || 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-cns3xxx/Kconfig"
442
443source "arch/arm/mach-davinci/Kconfig"
444
445source "arch/arm/mach-digicolor/Kconfig"
446
447source "arch/arm/mach-dove/Kconfig"
448
449source "arch/arm/mach-ep93xx/Kconfig"
450
451source "arch/arm/mach-exynos/Kconfig"
452
453source "arch/arm/mach-footbridge/Kconfig"
454
455source "arch/arm/mach-gemini/Kconfig"
456
457source "arch/arm/mach-highbank/Kconfig"
458
459source "arch/arm/mach-hisi/Kconfig"
460
461source "arch/arm/mach-hpe/Kconfig"
462
463source "arch/arm/mach-imx/Kconfig"
464
465source "arch/arm/mach-iop32x/Kconfig"
466
467source "arch/arm/mach-ixp4xx/Kconfig"
468
469source "arch/arm/mach-keystone/Kconfig"
470
471source "arch/arm/mach-lpc32xx/Kconfig"
472
473source "arch/arm/mach-mediatek/Kconfig"
474
475source "arch/arm/mach-meson/Kconfig"
476
477source "arch/arm/mach-milbeaut/Kconfig"
478
479source "arch/arm/mach-mmp/Kconfig"
480
481source "arch/arm/mach-moxart/Kconfig"
482
483source "arch/arm/mach-mstar/Kconfig"
484
485source "arch/arm/mach-mv78xx0/Kconfig"
486
487source "arch/arm/mach-mvebu/Kconfig"
488
489source "arch/arm/mach-mxs/Kconfig"
490
491source "arch/arm/mach-nomadik/Kconfig"
492
493source "arch/arm/mach-npcm/Kconfig"
494
495source "arch/arm/mach-nspire/Kconfig"
496
497source "arch/arm/mach-omap1/Kconfig"
498
499source "arch/arm/mach-omap2/Kconfig"
500
501source "arch/arm/mach-orion5x/Kconfig"
502
503source "arch/arm/mach-oxnas/Kconfig"
504
505source "arch/arm/mach-pxa/Kconfig"
506
507source "arch/arm/mach-qcom/Kconfig"
508
509source "arch/arm/mach-rda/Kconfig"
510
511source "arch/arm/mach-realtek/Kconfig"
512
513source "arch/arm/mach-rpc/Kconfig"
514
515source "arch/arm/mach-rockchip/Kconfig"
516
517source "arch/arm/mach-s3c/Kconfig"
518
519source "arch/arm/mach-s5pv210/Kconfig"
520
521source "arch/arm/mach-sa1100/Kconfig"
522
523source "arch/arm/mach-shmobile/Kconfig"
524
525source "arch/arm/mach-socfpga/Kconfig"
526
527source "arch/arm/mach-spear/Kconfig"
528
529source "arch/arm/mach-sti/Kconfig"
530
531source "arch/arm/mach-stm32/Kconfig"
532
533source "arch/arm/mach-sunplus/Kconfig"
534
535source "arch/arm/mach-sunxi/Kconfig"
536
537source "arch/arm/mach-tegra/Kconfig"
538
539source "arch/arm/mach-uniphier/Kconfig"
540
541source "arch/arm/mach-ux500/Kconfig"
542
543source "arch/arm/mach-versatile/Kconfig"
544
545source "arch/arm/mach-vt8500/Kconfig"
546
547source "arch/arm/mach-zynq/Kconfig"
548
549# ARMv7-M architecture
550config ARCH_LPC18XX
551	bool "NXP LPC18xx/LPC43xx"
552	depends on ARM_SINGLE_ARMV7M
553	select ARCH_HAS_RESET_CONTROLLER
554	select ARM_AMBA
555	select CLKSRC_LPC32XX
556	select PINCTRL
557	help
558	  Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
559	  high performance microcontrollers.
560
561config ARCH_MPS2
562	bool "ARM MPS2 platform"
563	depends on ARM_SINGLE_ARMV7M
564	select ARM_AMBA
565	select CLKSRC_MPS2
566	help
567	  Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
568	  with a range of available cores like Cortex-M3/M4/M7.
569
570	  Please, note that depends which Application Note is used memory map
571	  for the platform may vary, so adjustment of RAM base might be needed.
572
573# Definitions to make life easier
574config ARCH_ACORN
575	bool
576
577config PLAT_ORION
578	bool
579	select CLKSRC_MMIO
580	select GENERIC_IRQ_CHIP
581	select IRQ_DOMAIN
582
583config PLAT_ORION_LEGACY
584	bool
585	select PLAT_ORION
586
587config PLAT_VERSATILE
588	bool
589
590source "arch/arm/mm/Kconfig"
591
592config IWMMXT
593	bool "Enable iWMMXt support"
594	depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
595	default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
596	help
597	  Enable support for iWMMXt context switching at run time if
598	  running on a CPU that supports it.
599
600if !MMU
601source "arch/arm/Kconfig-nommu"
602endif
603
604config PJ4B_ERRATA_4742
605	bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
606	depends on CPU_PJ4B && MACH_ARMADA_370
607	default y
608	help
609	  When coming out of either a Wait for Interrupt (WFI) or a Wait for
610	  Event (WFE) IDLE states, a specific timing sensitivity exists between
611	  the retiring WFI/WFE instructions and the newly issued subsequent
612	  instructions.  This sensitivity can result in a CPU hang scenario.
613	  Workaround:
614	  The software must insert either a Data Synchronization Barrier (DSB)
615	  or Data Memory Barrier (DMB) command immediately after the WFI/WFE
616	  instruction
617
618config ARM_ERRATA_326103
619	bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
620	depends on CPU_V6
621	help
622	  Executing a SWP instruction to read-only memory does not set bit 11
623	  of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
624	  treat the access as a read, preventing a COW from occurring and
625	  causing the faulting task to livelock.
626
627config ARM_ERRATA_411920
628	bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
629	depends on CPU_V6 || CPU_V6K
630	help
631	  Invalidation of the Instruction Cache operation can
632	  fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
633	  It does not affect the MPCore. This option enables the ARM Ltd.
634	  recommended workaround.
635
636config ARM_ERRATA_430973
637	bool "ARM errata: Stale prediction on replaced interworking branch"
638	depends on CPU_V7
639	help
640	  This option enables the workaround for the 430973 Cortex-A8
641	  r1p* erratum. If a code sequence containing an ARM/Thumb
642	  interworking branch is replaced with another code sequence at the
643	  same virtual address, whether due to self-modifying code or virtual
644	  to physical address re-mapping, Cortex-A8 does not recover from the
645	  stale interworking branch prediction. This results in Cortex-A8
646	  executing the new code sequence in the incorrect ARM or Thumb state.
647	  The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
648	  and also flushes the branch target cache at every context switch.
649	  Note that setting specific bits in the ACTLR register may not be
650	  available in non-secure mode.
651
652config ARM_ERRATA_458693
653	bool "ARM errata: Processor deadlock when a false hazard is created"
654	depends on CPU_V7
655	depends on !ARCH_MULTIPLATFORM
656	help
657	  This option enables the workaround for the 458693 Cortex-A8 (r2p0)
658	  erratum. For very specific sequences of memory operations, it is
659	  possible for a hazard condition intended for a cache line to instead
660	  be incorrectly associated with a different cache line. This false
661	  hazard might then cause a processor deadlock. The workaround enables
662	  the L1 caching of the NEON accesses and disables the PLD instruction
663	  in the ACTLR register. Note that setting specific bits in the ACTLR
664	  register may not be available in non-secure mode.
665
666config ARM_ERRATA_460075
667	bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
668	depends on CPU_V7
669	depends on !ARCH_MULTIPLATFORM
670	help
671	  This option enables the workaround for the 460075 Cortex-A8 (r2p0)
672	  erratum. Any asynchronous access to the L2 cache may encounter a
673	  situation in which recent store transactions to the L2 cache are lost
674	  and overwritten with stale memory contents from external memory. The
675	  workaround disables the write-allocate mode for the L2 cache via the
676	  ACTLR register. Note that setting specific bits in the ACTLR register
677	  may not be available in non-secure mode.
678
679config ARM_ERRATA_742230
680	bool "ARM errata: DMB operation may be faulty"
681	depends on CPU_V7 && SMP
682	depends on !ARCH_MULTIPLATFORM
683	help
684	  This option enables the workaround for the 742230 Cortex-A9
685	  (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
686	  between two write operations may not ensure the correct visibility
687	  ordering of the two writes. This workaround sets a specific bit in
688	  the diagnostic register of the Cortex-A9 which causes the DMB
689	  instruction to behave as a DSB, ensuring the correct behaviour of
690	  the two writes.
691
692config ARM_ERRATA_742231
693	bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
694	depends on CPU_V7 && SMP
695	depends on !ARCH_MULTIPLATFORM
696	help
697	  This option enables the workaround for the 742231 Cortex-A9
698	  (r2p0..r2p2) erratum. Under certain conditions, specific to the
699	  Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
700	  accessing some data located in the same cache line, may get corrupted
701	  data due to bad handling of the address hazard when the line gets
702	  replaced from one of the CPUs at the same time as another CPU is
703	  accessing it. This workaround sets specific bits in the diagnostic
704	  register of the Cortex-A9 which reduces the linefill issuing
705	  capabilities of the processor.
706
707config ARM_ERRATA_643719
708	bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
709	depends on CPU_V7 && SMP
710	default y
711	help
712	  This option enables the workaround for the 643719 Cortex-A9 (prior to
713	  r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
714	  register returns zero when it should return one. The workaround
715	  corrects this value, ensuring cache maintenance operations which use
716	  it behave as intended and avoiding data corruption.
717
718config ARM_ERRATA_720789
719	bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
720	depends on CPU_V7
721	help
722	  This option enables the workaround for the 720789 Cortex-A9 (prior to
723	  r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
724	  broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
725	  As a consequence of this erratum, some TLB entries which should be
726	  invalidated are not, resulting in an incoherency in the system page
727	  tables. The workaround changes the TLB flushing routines to invalidate
728	  entries regardless of the ASID.
729
730config ARM_ERRATA_743622
731	bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
732	depends on CPU_V7
733	depends on !ARCH_MULTIPLATFORM
734	help
735	  This option enables the workaround for the 743622 Cortex-A9
736	  (r2p*) erratum. Under very rare conditions, a faulty
737	  optimisation in the Cortex-A9 Store Buffer may lead to data
738	  corruption. This workaround sets a specific bit in the diagnostic
739	  register of the Cortex-A9 which disables the Store Buffer
740	  optimisation, preventing the defect from occurring. This has no
741	  visible impact on the overall performance or power consumption of the
742	  processor.
743
744config ARM_ERRATA_751472
745	bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
746	depends on CPU_V7
747	depends on !ARCH_MULTIPLATFORM
748	help
749	  This option enables the workaround for the 751472 Cortex-A9 (prior
750	  to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
751	  completion of a following broadcasted operation if the second
752	  operation is received by a CPU before the ICIALLUIS has completed,
753	  potentially leading to corrupted entries in the cache or TLB.
754
755config ARM_ERRATA_754322
756	bool "ARM errata: possible faulty MMU translations following an ASID switch"
757	depends on CPU_V7
758	help
759	  This option enables the workaround for the 754322 Cortex-A9 (r2p*,
760	  r3p*) erratum. A speculative memory access may cause a page table walk
761	  which starts prior to an ASID switch but completes afterwards. This
762	  can populate the micro-TLB with a stale entry which may be hit with
763	  the new ASID. This workaround places two dsb instructions in the mm
764	  switching code so that no page table walks can cross the ASID switch.
765
766config ARM_ERRATA_754327
767	bool "ARM errata: no automatic Store Buffer drain"
768	depends on CPU_V7 && SMP
769	help
770	  This option enables the workaround for the 754327 Cortex-A9 (prior to
771	  r2p0) erratum. The Store Buffer does not have any automatic draining
772	  mechanism and therefore a livelock may occur if an external agent
773	  continuously polls a memory location waiting to observe an update.
774	  This workaround defines cpu_relax() as smp_mb(), preventing correctly
775	  written polling loops from denying visibility of updates to memory.
776
777config ARM_ERRATA_364296
778	bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
779	depends on CPU_V6
780	help
781	  This options enables the workaround for the 364296 ARM1136
782	  r0p2 erratum (possible cache data corruption with
783	  hit-under-miss enabled). It sets the undocumented bit 31 in
784	  the auxiliary control register and the FI bit in the control
785	  register, thus disabling hit-under-miss without putting the
786	  processor into full low interrupt latency mode. ARM11MPCore
787	  is not affected.
788
789config ARM_ERRATA_764369
790	bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
791	depends on CPU_V7 && SMP
792	help
793	  This option enables the workaround for erratum 764369
794	  affecting Cortex-A9 MPCore with two or more processors (all
795	  current revisions). Under certain timing circumstances, a data
796	  cache line maintenance operation by MVA targeting an Inner
797	  Shareable memory region may fail to proceed up to either the
798	  Point of Coherency or to the Point of Unification of the
799	  system. This workaround adds a DSB instruction before the
800	  relevant cache maintenance functions and sets a specific bit
801	  in the diagnostic control register of the SCU.
802
803config ARM_ERRATA_764319
804	bool "ARM errata: Read to DBGPRSR and DBGOSLSR may generate Undefined instruction"
805	depends on CPU_V7
806	help
807	  This option enables the workaround for the 764319 Cortex A-9 erratum.
808	  CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
809	  unexpected Undefined Instruction exception when the DBGSWENABLE
810	  external pin is set to 0, even when the CP14 accesses are performed
811	  from a privileged mode. This work around catches the exception in a
812	  way the kernel does not stop execution.
813
814config ARM_ERRATA_775420
815       bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
816       depends on CPU_V7
817       help
818	 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
819	 r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
820	 operation aborts with MMU exception, it might cause the processor
821	 to deadlock. This workaround puts DSB before executing ISB if
822	 an abort may occur on cache maintenance.
823
824config ARM_ERRATA_798181
825	bool "ARM errata: TLBI/DSB failure on Cortex-A15"
826	depends on CPU_V7 && SMP
827	help
828	  On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
829	  adequately shooting down all use of the old entries. This
830	  option enables the Linux kernel workaround for this erratum
831	  which sends an IPI to the CPUs that are running the same ASID
832	  as the one being invalidated.
833
834config ARM_ERRATA_773022
835	bool "ARM errata: incorrect instructions may be executed from loop buffer"
836	depends on CPU_V7
837	help
838	  This option enables the workaround for the 773022 Cortex-A15
839	  (up to r0p4) erratum. In certain rare sequences of code, the
840	  loop buffer may deliver incorrect instructions. This
841	  workaround disables the loop buffer to avoid the erratum.
842
843config ARM_ERRATA_818325_852422
844	bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
845	depends on CPU_V7
846	help
847	  This option enables the workaround for:
848	  - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
849	    instruction might deadlock.  Fixed in r0p1.
850	  - Cortex-A12 852422: Execution of a sequence of instructions might
851	    lead to either a data corruption or a CPU deadlock.  Not fixed in
852	    any Cortex-A12 cores yet.
853	  This workaround for all both errata involves setting bit[12] of the
854	  Feature Register. This bit disables an optimisation applied to a
855	  sequence of 2 instructions that use opposing condition codes.
856
857config ARM_ERRATA_821420
858	bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
859	depends on CPU_V7
860	help
861	  This option enables the workaround for the 821420 Cortex-A12
862	  (all revs) erratum. In very rare timing conditions, a sequence
863	  of VMOV to Core registers instructions, for which the second
864	  one is in the shadow of a branch or abort, can lead to a
865	  deadlock when the VMOV instructions are issued out-of-order.
866
867config ARM_ERRATA_825619
868	bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
869	depends on CPU_V7
870	help
871	  This option enables the workaround for the 825619 Cortex-A12
872	  (all revs) erratum. Within rare timing constraints, executing a
873	  DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
874	  and Device/Strongly-Ordered loads and stores might cause deadlock
875
876config ARM_ERRATA_857271
877	bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
878	depends on CPU_V7
879	help
880	  This option enables the workaround for the 857271 Cortex-A12
881	  (all revs) erratum. Under very rare timing conditions, the CPU might
882	  hang. The workaround is expected to have a < 1% performance impact.
883
884config ARM_ERRATA_852421
885	bool "ARM errata: A17: DMB ST might fail to create order between stores"
886	depends on CPU_V7
887	help
888	  This option enables the workaround for the 852421 Cortex-A17
889	  (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
890	  execution of a DMB ST instruction might fail to properly order
891	  stores from GroupA and stores from GroupB.
892
893config ARM_ERRATA_852423
894	bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
895	depends on CPU_V7
896	help
897	  This option enables the workaround for:
898	  - Cortex-A17 852423: Execution of a sequence of instructions might
899	    lead to either a data corruption or a CPU deadlock.  Not fixed in
900	    any Cortex-A17 cores yet.
901	  This is identical to Cortex-A12 erratum 852422.  It is a separate
902	  config option from the A12 erratum due to the way errata are checked
903	  for and handled.
904
905config ARM_ERRATA_857272
906	bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
907	depends on CPU_V7
908	help
909	  This option enables the workaround for the 857272 Cortex-A17 erratum.
910	  This erratum is not known to be fixed in any A17 revision.
911	  This is identical to Cortex-A12 erratum 857271.  It is a separate
912	  config option from the A12 erratum due to the way errata are checked
913	  for and handled.
914
915endmenu
916
917source "arch/arm/common/Kconfig"
918
919menu "Bus support"
920
921config ISA
922	bool
923	help
924	  Find out whether you have ISA slots on your motherboard.  ISA is the
925	  name of a bus system, i.e. the way the CPU talks to the other stuff
926	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
927	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
928	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
929
930# Select ISA DMA interface
931config ISA_DMA_API
932	bool
933
934config PCI_NANOENGINE
935	bool "BSE nanoEngine PCI support"
936	depends on SA1100_NANOENGINE
937	help
938	  Enable PCI on the BSE nanoEngine board.
939
940config ARM_ERRATA_814220
941	bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
942	depends on CPU_V7
943	help
944	  The v7 ARM states that all cache and branch predictor maintenance
945	  operations that do not specify an address execute, relative to
946	  each other, in program order.
947	  However, because of this erratum, an L2 set/way cache maintenance
948	  operation can overtake an L1 set/way cache maintenance operation.
949	  This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
950	  r0p4, r0p5.
951
952endmenu
953
954menu "Kernel Features"
955
956config HAVE_SMP
957	bool
958	help
959	  This option should be selected by machines which have an SMP-
960	  capable CPU.
961
962	  The only effect of this option is to make the SMP-related
963	  options available to the user for configuration.
964
965config SMP
966	bool "Symmetric Multi-Processing"
967	depends on CPU_V6K || CPU_V7
968	depends on HAVE_SMP
969	depends on MMU || ARM_MPU
970	select IRQ_WORK
971	help
972	  This enables support for systems with more than one CPU. If you have
973	  a system with only one CPU, say N. If you have a system with more
974	  than one CPU, say Y.
975
976	  If you say N here, the kernel will run on uni- and multiprocessor
977	  machines, but will use only one CPU of a multiprocessor machine. If
978	  you say Y here, the kernel will run on many, but not all,
979	  uniprocessor machines. On a uniprocessor machine, the kernel
980	  will run faster if you say N here.
981
982	  See also <file:Documentation/x86/i386/IO-APIC.rst>,
983	  <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
984	  <http://tldp.org/HOWTO/SMP-HOWTO.html>.
985
986	  If you don't know what to do here, say N.
987
988config SMP_ON_UP
989	bool "Allow booting SMP kernel on uniprocessor systems"
990	depends on SMP && MMU
991	default y
992	help
993	  SMP kernels contain instructions which fail on non-SMP processors.
994	  Enabling this option allows the kernel to modify itself to make
995	  these instructions safe.  Disabling it allows about 1K of space
996	  savings.
997
998	  If you don't know what to do here, say Y.
999
1000
1001config CURRENT_POINTER_IN_TPIDRURO
1002	def_bool y
1003	depends on CPU_32v6K && !CPU_V6
1004
1005config IRQSTACKS
1006	def_bool y
1007	select HAVE_IRQ_EXIT_ON_IRQ_STACK
1008	select HAVE_SOFTIRQ_ON_OWN_STACK
1009
1010config ARM_CPU_TOPOLOGY
1011	bool "Support cpu topology definition"
1012	depends on SMP && CPU_V7
1013	default y
1014	help
1015	  Support ARM cpu topology definition. The MPIDR register defines
1016	  affinity between processors which is then used to describe the cpu
1017	  topology of an ARM System.
1018
1019config SCHED_MC
1020	bool "Multi-core scheduler support"
1021	depends on ARM_CPU_TOPOLOGY
1022	help
1023	  Multi-core scheduler support improves the CPU scheduler's decision
1024	  making when dealing with multi-core CPU chips at a cost of slightly
1025	  increased overhead in some places. If unsure say N here.
1026
1027config SCHED_SMT
1028	bool "SMT scheduler support"
1029	depends on ARM_CPU_TOPOLOGY
1030	help
1031	  Improves the CPU scheduler's decision making when dealing with
1032	  MultiThreading at a cost of slightly increased overhead in some
1033	  places. If unsure say N here.
1034
1035config HAVE_ARM_SCU
1036	bool
1037	help
1038	  This option enables support for the ARM snoop control unit
1039
1040config HAVE_ARM_ARCH_TIMER
1041	bool "Architected timer support"
1042	depends on CPU_V7
1043	select ARM_ARCH_TIMER
1044	help
1045	  This option enables support for the ARM architected timer
1046
1047config HAVE_ARM_TWD
1048	bool
1049	help
1050	  This options enables support for the ARM timer and watchdog unit
1051
1052config MCPM
1053	bool "Multi-Cluster Power Management"
1054	depends on CPU_V7 && SMP
1055	help
1056	  This option provides the common power management infrastructure
1057	  for (multi-)cluster based systems, such as big.LITTLE based
1058	  systems.
1059
1060config MCPM_QUAD_CLUSTER
1061	bool
1062	depends on MCPM
1063	help
1064	  To avoid wasting resources unnecessarily, MCPM only supports up
1065	  to 2 clusters by default.
1066	  Platforms with 3 or 4 clusters that use MCPM must select this
1067	  option to allow the additional clusters to be managed.
1068
1069config BIG_LITTLE
1070	bool "big.LITTLE support (Experimental)"
1071	depends on CPU_V7 && SMP
1072	select MCPM
1073	help
1074	  This option enables support selections for the big.LITTLE
1075	  system architecture.
1076
1077config BL_SWITCHER
1078	bool "big.LITTLE switcher support"
1079	depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
1080	select CPU_PM
1081	help
1082	  The big.LITTLE "switcher" provides the core functionality to
1083	  transparently handle transition between a cluster of A15's
1084	  and a cluster of A7's in a big.LITTLE system.
1085
1086config BL_SWITCHER_DUMMY_IF
1087	tristate "Simple big.LITTLE switcher user interface"
1088	depends on BL_SWITCHER && DEBUG_KERNEL
1089	help
1090	  This is a simple and dummy char dev interface to control
1091	  the big.LITTLE switcher core code.  It is meant for
1092	  debugging purposes only.
1093
1094choice
1095	prompt "Memory split"
1096	depends on MMU
1097	default VMSPLIT_3G
1098	help
1099	  Select the desired split between kernel and user memory.
1100
1101	  If you are not absolutely sure what you are doing, leave this
1102	  option alone!
1103
1104	config VMSPLIT_3G
1105		bool "3G/1G user/kernel split"
1106	config VMSPLIT_3G_OPT
1107		depends on !ARM_LPAE
1108		bool "3G/1G user/kernel split (for full 1G low memory)"
1109	config VMSPLIT_2G
1110		bool "2G/2G user/kernel split"
1111	config VMSPLIT_1G
1112		bool "1G/3G user/kernel split"
1113endchoice
1114
1115config PAGE_OFFSET
1116	hex
1117	default PHYS_OFFSET if !MMU
1118	default 0x40000000 if VMSPLIT_1G
1119	default 0x80000000 if VMSPLIT_2G
1120	default 0xB0000000 if VMSPLIT_3G_OPT
1121	default 0xC0000000
1122
1123config KASAN_SHADOW_OFFSET
1124	hex
1125	depends on KASAN
1126	default 0x1f000000 if PAGE_OFFSET=0x40000000
1127	default 0x5f000000 if PAGE_OFFSET=0x80000000
1128	default 0x9f000000 if PAGE_OFFSET=0xC0000000
1129	default 0x8f000000 if PAGE_OFFSET=0xB0000000
1130	default 0xffffffff
1131
1132config NR_CPUS
1133	int "Maximum number of CPUs (2-32)"
1134	range 2 16 if DEBUG_KMAP_LOCAL
1135	range 2 32 if !DEBUG_KMAP_LOCAL
1136	depends on SMP
1137	default "4"
1138	help
1139	  The maximum number of CPUs that the kernel can support.
1140	  Up to 32 CPUs can be supported, or up to 16 if kmap_local()
1141	  debugging is enabled, which uses half of the per-CPU fixmap
1142	  slots as guard regions.
1143
1144config HOTPLUG_CPU
1145	bool "Support for hot-pluggable CPUs"
1146	depends on SMP
1147	select GENERIC_IRQ_MIGRATION
1148	help
1149	  Say Y here to experiment with turning CPUs off and on.  CPUs
1150	  can be controlled through /sys/devices/system/cpu.
1151
1152config ARM_PSCI
1153	bool "Support for the ARM Power State Coordination Interface (PSCI)"
1154	depends on HAVE_ARM_SMCCC
1155	select ARM_PSCI_FW
1156	help
1157	  Say Y here if you want Linux to communicate with system firmware
1158	  implementing the PSCI specification for CPU-centric power
1159	  management operations described in ARM document number ARM DEN
1160	  0022A ("Power State Coordination Interface System Software on
1161	  ARM processors").
1162
1163config HZ_FIXED
1164	int
1165	default 128 if SOC_AT91RM9200
1166	default 0
1167
1168choice
1169	depends on HZ_FIXED = 0
1170	prompt "Timer frequency"
1171
1172config HZ_100
1173	bool "100 Hz"
1174
1175config HZ_200
1176	bool "200 Hz"
1177
1178config HZ_250
1179	bool "250 Hz"
1180
1181config HZ_300
1182	bool "300 Hz"
1183
1184config HZ_500
1185	bool "500 Hz"
1186
1187config HZ_1000
1188	bool "1000 Hz"
1189
1190endchoice
1191
1192config HZ
1193	int
1194	default HZ_FIXED if HZ_FIXED != 0
1195	default 100 if HZ_100
1196	default 200 if HZ_200
1197	default 250 if HZ_250
1198	default 300 if HZ_300
1199	default 500 if HZ_500
1200	default 1000
1201
1202config SCHED_HRTICK
1203	def_bool HIGH_RES_TIMERS
1204
1205config THUMB2_KERNEL
1206	bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1207	depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1208	default y if CPU_THUMBONLY
1209	select ARM_UNWIND
1210	help
1211	  By enabling this option, the kernel will be compiled in
1212	  Thumb-2 mode.
1213
1214	  If unsure, say N.
1215
1216config ARM_PATCH_IDIV
1217	bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
1218	depends on CPU_32v7
1219	default y
1220	help
1221	  The ARM compiler inserts calls to __aeabi_idiv() and
1222	  __aeabi_uidiv() when it needs to perform division on signed
1223	  and unsigned integers. Some v7 CPUs have support for the sdiv
1224	  and udiv instructions that can be used to implement those
1225	  functions.
1226
1227	  Enabling this option allows the kernel to modify itself to
1228	  replace the first two instructions of these library functions
1229	  with the sdiv or udiv plus "bx lr" instructions when the CPU
1230	  it is running on supports them. Typically this will be faster
1231	  and less power intensive than running the original library
1232	  code to do integer division.
1233
1234config AEABI
1235	bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1236		!CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1237	default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
1238	help
1239	  This option allows for the kernel to be compiled using the latest
1240	  ARM ABI (aka EABI).  This is only useful if you are using a user
1241	  space environment that is also compiled with EABI.
1242
1243	  Since there are major incompatibilities between the legacy ABI and
1244	  EABI, especially with regard to structure member alignment, this
1245	  option also changes the kernel syscall calling convention to
1246	  disambiguate both ABIs and allow for backward compatibility support
1247	  (selected with CONFIG_OABI_COMPAT).
1248
1249	  To use this you need GCC version 4.0.0 or later.
1250
1251config OABI_COMPAT
1252	bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1253	depends on AEABI && !THUMB2_KERNEL
1254	help
1255	  This option preserves the old syscall interface along with the
1256	  new (ARM EABI) one. It also provides a compatibility layer to
1257	  intercept syscalls that have structure arguments which layout
1258	  in memory differs between the legacy ABI and the new ARM EABI
1259	  (only for non "thumb" binaries). This option adds a tiny
1260	  overhead to all syscalls and produces a slightly larger kernel.
1261
1262	  The seccomp filter system will not be available when this is
1263	  selected, since there is no way yet to sensibly distinguish
1264	  between calling conventions during filtering.
1265
1266	  If you know you'll be using only pure EABI user space then you
1267	  can say N here. If this option is not selected and you attempt
1268	  to execute a legacy ABI binary then the result will be
1269	  UNPREDICTABLE (in fact it can be predicted that it won't work
1270	  at all). If in doubt say N.
1271
1272config ARCH_SELECT_MEMORY_MODEL
1273	def_bool y
1274
1275config ARCH_FLATMEM_ENABLE
1276	def_bool !(ARCH_RPC || ARCH_SA1100)
1277
1278config ARCH_SPARSEMEM_ENABLE
1279	def_bool !ARCH_FOOTBRIDGE
1280	select SPARSEMEM_STATIC if SPARSEMEM
1281
1282config HIGHMEM
1283	bool "High Memory Support"
1284	depends on MMU
1285	select KMAP_LOCAL
1286	select KMAP_LOCAL_NON_LINEAR_PTE_ARRAY
1287	help
1288	  The address space of ARM processors is only 4 Gigabytes large
1289	  and it has to accommodate user address space, kernel address
1290	  space as well as some memory mapped IO. That means that, if you
1291	  have a large amount of physical memory and/or IO, not all of the
1292	  memory can be "permanently mapped" by the kernel. The physical
1293	  memory that is not permanently mapped is called "high memory".
1294
1295	  Depending on the selected kernel/user memory split, minimum
1296	  vmalloc space and actual amount of RAM, you may not need this
1297	  option which should result in a slightly faster kernel.
1298
1299	  If unsure, say n.
1300
1301config HIGHPTE
1302	bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1303	depends on HIGHMEM
1304	default y
1305	help
1306	  The VM uses one page of physical memory for each page table.
1307	  For systems with a lot of processes, this can use a lot of
1308	  precious low memory, eventually leading to low memory being
1309	  consumed by page tables.  Setting this option will allow
1310	  user-space 2nd level page tables to reside in high memory.
1311
1312config CPU_SW_DOMAIN_PAN
1313	bool "Enable use of CPU domains to implement privileged no-access"
1314	depends on MMU && !ARM_LPAE
1315	default y
1316	help
1317	  Increase kernel security by ensuring that normal kernel accesses
1318	  are unable to access userspace addresses.  This can help prevent
1319	  use-after-free bugs becoming an exploitable privilege escalation
1320	  by ensuring that magic values (such as LIST_POISON) will always
1321	  fault when dereferenced.
1322
1323	  CPUs with low-vector mappings use a best-efforts implementation.
1324	  Their lower 1MB needs to remain accessible for the vectors, but
1325	  the remainder of userspace will become appropriately inaccessible.
1326
1327config HW_PERF_EVENTS
1328	def_bool y
1329	depends on ARM_PMU
1330
1331config ARM_MODULE_PLTS
1332	bool "Use PLTs to allow module memory to spill over into vmalloc area"
1333	depends on MODULES
1334	select KASAN_VMALLOC if KASAN
1335	default y
1336	help
1337	  Allocate PLTs when loading modules so that jumps and calls whose
1338	  targets are too far away for their relative offsets to be encoded
1339	  in the instructions themselves can be bounced via veneers in the
1340	  module's PLT. This allows modules to be allocated in the generic
1341	  vmalloc area after the dedicated module memory area has been
1342	  exhausted. The modules will use slightly more memory, but after
1343	  rounding up to page size, the actual memory footprint is usually
1344	  the same.
1345
1346	  Disabling this is usually safe for small single-platform
1347	  configurations. If unsure, say y.
1348
1349config ARCH_FORCE_MAX_ORDER
1350	int "Maximum zone order"
1351	default "12" if SOC_AM33XX
1352	default "9" if SA1111
1353	default "11"
1354	help
1355	  The kernel memory allocator divides physically contiguous memory
1356	  blocks into "zones", where each zone is a power of two number of
1357	  pages.  This option selects the largest power of two that the kernel
1358	  keeps in the memory allocator.  If you need to allocate very large
1359	  blocks of physically contiguous memory, then you may need to
1360	  increase this value.
1361
1362	  This config option is actually maximum order plus one. For example,
1363	  a value of 11 means that the largest free memory block is 2^10 pages.
1364
1365config ALIGNMENT_TRAP
1366	def_bool CPU_CP15_MMU
1367	select HAVE_PROC_CPU if PROC_FS
1368	help
1369	  ARM processors cannot fetch/store information which is not
1370	  naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1371	  address divisible by 4. On 32-bit ARM processors, these non-aligned
1372	  fetch/store instructions will be emulated in software if you say
1373	  here, which has a severe performance impact. This is necessary for
1374	  correct operation of some network protocols. With an IP-only
1375	  configuration it is safe to say N, otherwise say Y.
1376
1377config UACCESS_WITH_MEMCPY
1378	bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1379	depends on MMU
1380	default y if CPU_FEROCEON
1381	help
1382	  Implement faster copy_to_user and clear_user methods for CPU
1383	  cores where a 8-word STM instruction give significantly higher
1384	  memory write throughput than a sequence of individual 32bit stores.
1385
1386	  A possible side effect is a slight increase in scheduling latency
1387	  between threads sharing the same address space if they invoke
1388	  such copy operations with large buffers.
1389
1390	  However, if the CPU data cache is using a write-allocate mode,
1391	  this option is unlikely to provide any performance gain.
1392
1393config PARAVIRT
1394	bool "Enable paravirtualization code"
1395	help
1396	  This changes the kernel so it can modify itself when it is run
1397	  under a hypervisor, potentially improving performance significantly
1398	  over full virtualization.
1399
1400config PARAVIRT_TIME_ACCOUNTING
1401	bool "Paravirtual steal time accounting"
1402	select PARAVIRT
1403	help
1404	  Select this option to enable fine granularity task steal time
1405	  accounting. Time spent executing other tasks in parallel with
1406	  the current vCPU is discounted from the vCPU power. To account for
1407	  that, there can be a small performance impact.
1408
1409	  If in doubt, say N here.
1410
1411config XEN_DOM0
1412	def_bool y
1413	depends on XEN
1414
1415config XEN
1416	bool "Xen guest support on ARM"
1417	depends on ARM && AEABI && OF
1418	depends on CPU_V7 && !CPU_V6
1419	depends on !GENERIC_ATOMIC64
1420	depends on MMU
1421	select ARCH_DMA_ADDR_T_64BIT
1422	select ARM_PSCI
1423	select SWIOTLB
1424	select SWIOTLB_XEN
1425	select PARAVIRT
1426	help
1427	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1428
1429config CC_HAVE_STACKPROTECTOR_TLS
1430	def_bool $(cc-option,-mtp=cp15 -mstack-protector-guard=tls -mstack-protector-guard-offset=0)
1431
1432config STACKPROTECTOR_PER_TASK
1433	bool "Use a unique stack canary value for each task"
1434	depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA
1435	depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS
1436	select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS
1437	default y
1438	help
1439	  Due to the fact that GCC uses an ordinary symbol reference from
1440	  which to load the value of the stack canary, this value can only
1441	  change at reboot time on SMP systems, and all tasks running in the
1442	  kernel's address space are forced to use the same canary value for
1443	  the entire duration that the system is up.
1444
1445	  Enable this option to switch to a different method that uses a
1446	  different canary value for each task.
1447
1448endmenu
1449
1450menu "Boot options"
1451
1452config USE_OF
1453	bool "Flattened Device Tree support"
1454	select IRQ_DOMAIN
1455	select OF
1456	help
1457	  Include support for flattened device tree machine descriptions.
1458
1459config ATAGS
1460	bool "Support for the traditional ATAGS boot data passing"
1461	default y
1462	help
1463	  This is the traditional way of passing data to the kernel at boot
1464	  time. If you are solely relying on the flattened device tree (or
1465	  the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1466	  to remove ATAGS support from your kernel binary.
1467
1468config UNUSED_BOARD_FILES
1469	bool "Board support for machines without known users"
1470	depends on ATAGS
1471	help
1472	  Most ATAGS based board files are completely unused and are
1473	  scheduled for removal in early 2023, and left out of kernels
1474	  by default now.  If you are using a board file that is marked
1475	  as unused, turn on this option to build support into the kernel.
1476
1477	  To keep support for your individual board from being removed,
1478	  send a reply to the email discussion at
1479	  https://lore.kernel.org/all/CAK8P3a0Z9vGEQbVRBo84bSyPFM-LF+hs5w8ZA51g2Z+NsdtDQA@mail.gmail.com/
1480
1481config DEPRECATED_PARAM_STRUCT
1482	bool "Provide old way to pass kernel parameters"
1483	depends on ATAGS
1484	help
1485	  This was deprecated in 2001 and announced to live on for 5 years.
1486	  Some old boot loaders still use this way.
1487
1488# Compressed boot loader in ROM.  Yes, we really want to ask about
1489# TEXT and BSS so we preserve their values in the config files.
1490config ZBOOT_ROM_TEXT
1491	hex "Compressed ROM boot loader base address"
1492	default 0x0
1493	help
1494	  The physical address at which the ROM-able zImage is to be
1495	  placed in the target.  Platforms which normally make use of
1496	  ROM-able zImage formats normally set this to a suitable
1497	  value in their defconfig file.
1498
1499	  If ZBOOT_ROM is not enabled, this has no effect.
1500
1501config ZBOOT_ROM_BSS
1502	hex "Compressed ROM boot loader BSS address"
1503	default 0x0
1504	help
1505	  The base address of an area of read/write memory in the target
1506	  for the ROM-able zImage which must be available while the
1507	  decompressor is running. It must be large enough to hold the
1508	  entire decompressed kernel plus an additional 128 KiB.
1509	  Platforms which normally make use of ROM-able zImage formats
1510	  normally set this to a suitable value in their defconfig file.
1511
1512	  If ZBOOT_ROM is not enabled, this has no effect.
1513
1514config ZBOOT_ROM
1515	bool "Compressed boot loader in ROM/flash"
1516	depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1517	depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1518	help
1519	  Say Y here if you intend to execute your compressed kernel image
1520	  (zImage) directly from ROM or flash.  If unsure, say N.
1521
1522config ARM_APPENDED_DTB
1523	bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1524	depends on OF
1525	help
1526	  With this option, the boot code will look for a device tree binary
1527	  (DTB) appended to zImage
1528	  (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1529
1530	  This is meant as a backward compatibility convenience for those
1531	  systems with a bootloader that can't be upgraded to accommodate
1532	  the documented boot protocol using a device tree.
1533
1534	  Beware that there is very little in terms of protection against
1535	  this option being confused by leftover garbage in memory that might
1536	  look like a DTB header after a reboot if no actual DTB is appended
1537	  to zImage.  Do not leave this option active in a production kernel
1538	  if you don't intend to always append a DTB.  Proper passing of the
1539	  location into r2 of a bootloader provided DTB is always preferable
1540	  to this option.
1541
1542config ARM_ATAG_DTB_COMPAT
1543	bool "Supplement the appended DTB with traditional ATAG information"
1544	depends on ARM_APPENDED_DTB
1545	help
1546	  Some old bootloaders can't be updated to a DTB capable one, yet
1547	  they provide ATAGs with memory configuration, the ramdisk address,
1548	  the kernel cmdline string, etc.  Such information is dynamically
1549	  provided by the bootloader and can't always be stored in a static
1550	  DTB.  To allow a device tree enabled kernel to be used with such
1551	  bootloaders, this option allows zImage to extract the information
1552	  from the ATAG list and store it at run time into the appended DTB.
1553
1554choice
1555	prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1556	default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1557
1558config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1559	bool "Use bootloader kernel arguments if available"
1560	help
1561	  Uses the command-line options passed by the boot loader instead of
1562	  the device tree bootargs property. If the boot loader doesn't provide
1563	  any, the device tree bootargs property will be used.
1564
1565config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1566	bool "Extend with bootloader kernel arguments"
1567	help
1568	  The command-line arguments provided by the boot loader will be
1569	  appended to the the device tree bootargs property.
1570
1571endchoice
1572
1573config CMDLINE
1574	string "Default kernel command string"
1575	default ""
1576	help
1577	  On some architectures (e.g. CATS), there is currently no way
1578	  for the boot loader to pass arguments to the kernel. For these
1579	  architectures, you should supply some command-line options at build
1580	  time by entering them here. As a minimum, you should specify the
1581	  memory size and the root device (e.g., mem=64M root=/dev/nfs).
1582
1583choice
1584	prompt "Kernel command line type" if CMDLINE != ""
1585	default CMDLINE_FROM_BOOTLOADER
1586
1587config CMDLINE_FROM_BOOTLOADER
1588	bool "Use bootloader kernel arguments if available"
1589	help
1590	  Uses the command-line options passed by the boot loader. If
1591	  the boot loader doesn't provide any, the default kernel command
1592	  string provided in CMDLINE will be used.
1593
1594config CMDLINE_EXTEND
1595	bool "Extend bootloader kernel arguments"
1596	help
1597	  The command-line arguments provided by the boot loader will be
1598	  appended to the default kernel command string.
1599
1600config CMDLINE_FORCE
1601	bool "Always use the default kernel command string"
1602	help
1603	  Always use the default kernel command string, even if the boot
1604	  loader passes other arguments to the kernel.
1605	  This is useful if you cannot or don't want to change the
1606	  command-line options your boot loader passes to the kernel.
1607endchoice
1608
1609config XIP_KERNEL
1610	bool "Kernel Execute-In-Place from ROM"
1611	depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
1612	depends on !ARM_PATCH_IDIV && !ARM_PATCH_PHYS_VIRT && !SMP_ON_UP
1613	help
1614	  Execute-In-Place allows the kernel to run from non-volatile storage
1615	  directly addressable by the CPU, such as NOR flash. This saves RAM
1616	  space since the text section of the kernel is not loaded from flash
1617	  to RAM.  Read-write sections, such as the data section and stack,
1618	  are still copied to RAM.  The XIP kernel is not compressed since
1619	  it has to run directly from flash, so it will take more space to
1620	  store it.  The flash address used to link the kernel object files,
1621	  and for storing it, is configuration dependent. Therefore, if you
1622	  say Y here, you must know the proper physical address where to
1623	  store the kernel image depending on your own flash memory usage.
1624
1625	  Also note that the make target becomes "make xipImage" rather than
1626	  "make zImage" or "make Image".  The final kernel binary to put in
1627	  ROM memory will be arch/arm/boot/xipImage.
1628
1629	  If unsure, say N.
1630
1631config XIP_PHYS_ADDR
1632	hex "XIP Kernel Physical Location"
1633	depends on XIP_KERNEL
1634	default "0x00080000"
1635	help
1636	  This is the physical address in your flash memory the kernel will
1637	  be linked for and stored to.  This address is dependent on your
1638	  own flash usage.
1639
1640config XIP_DEFLATED_DATA
1641	bool "Store kernel .data section compressed in ROM"
1642	depends on XIP_KERNEL
1643	select ZLIB_INFLATE
1644	help
1645	  Before the kernel is actually executed, its .data section has to be
1646	  copied to RAM from ROM. This option allows for storing that data
1647	  in compressed form and decompressed to RAM rather than merely being
1648	  copied, saving some precious ROM space. A possible drawback is a
1649	  slightly longer boot delay.
1650
1651config KEXEC
1652	bool "Kexec system call (EXPERIMENTAL)"
1653	depends on (!SMP || PM_SLEEP_SMP)
1654	depends on MMU
1655	select KEXEC_CORE
1656	help
1657	  kexec is a system call that implements the ability to shutdown your
1658	  current kernel, and to start another kernel.  It is like a reboot
1659	  but it is independent of the system firmware.   And like a reboot
1660	  you can start any kernel with it, not just Linux.
1661
1662	  It is an ongoing process to be certain the hardware in a machine
1663	  is properly shutdown, so do not be surprised if this code does not
1664	  initially work for you.
1665
1666config ATAGS_PROC
1667	bool "Export atags in procfs"
1668	depends on ATAGS && KEXEC
1669	default y
1670	help
1671	  Should the atags used to boot the kernel be exported in an "atags"
1672	  file in procfs. Useful with kexec.
1673
1674config CRASH_DUMP
1675	bool "Build kdump crash kernel (EXPERIMENTAL)"
1676	help
1677	  Generate crash dump after being started by kexec. This should
1678	  be normally only set in special crash dump kernels which are
1679	  loaded in the main kernel with kexec-tools into a specially
1680	  reserved region and then later executed after a crash by
1681	  kdump/kexec. The crash dump kernel must be compiled to a
1682	  memory address not used by the main kernel
1683
1684	  For more details see Documentation/admin-guide/kdump/kdump.rst
1685
1686config AUTO_ZRELADDR
1687	bool "Auto calculation of the decompressed kernel image address" if !ARCH_MULTIPLATFORM
1688	default !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
1689	help
1690	  ZRELADDR is the physical address where the decompressed kernel
1691	  image will be placed. If AUTO_ZRELADDR is selected, the address
1692	  will be determined at run-time, either by masking the current IP
1693	  with 0xf8000000, or, if invalid, from the DTB passed in r2.
1694	  This assumes the zImage being placed in the first 128MB from
1695	  start of memory.
1696
1697config EFI_STUB
1698	bool
1699
1700config EFI
1701	bool "UEFI runtime support"
1702	depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
1703	select UCS2_STRING
1704	select EFI_PARAMS_FROM_FDT
1705	select EFI_STUB
1706	select EFI_GENERIC_STUB
1707	select EFI_RUNTIME_WRAPPERS
1708	help
1709	  This option provides support for runtime services provided
1710	  by UEFI firmware (such as non-volatile variables, realtime
1711	  clock, and platform reset). A UEFI stub is also provided to
1712	  allow the kernel to be booted as an EFI application. This
1713	  is only useful for kernels that may run on systems that have
1714	  UEFI firmware.
1715
1716config DMI
1717	bool "Enable support for SMBIOS (DMI) tables"
1718	depends on EFI
1719	default y
1720	help
1721	  This enables SMBIOS/DMI feature for systems.
1722
1723	  This option is only useful on systems that have UEFI firmware.
1724	  However, even with this option, the resultant kernel should
1725	  continue to boot on existing non-UEFI platforms.
1726
1727	  NOTE: This does *NOT* enable or encourage the use of DMI quirks,
1728	  i.e., the the practice of identifying the platform via DMI to
1729	  decide whether certain workarounds for buggy hardware and/or
1730	  firmware need to be enabled. This would require the DMI subsystem
1731	  to be enabled much earlier than we do on ARM, which is non-trivial.
1732
1733endmenu
1734
1735menu "CPU Power Management"
1736
1737source "drivers/cpufreq/Kconfig"
1738
1739source "drivers/cpuidle/Kconfig"
1740
1741endmenu
1742
1743menu "Floating point emulation"
1744
1745comment "At least one emulation must be selected"
1746
1747config FPE_NWFPE
1748	bool "NWFPE math emulation"
1749	depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
1750	help
1751	  Say Y to include the NWFPE floating point emulator in the kernel.
1752	  This is necessary to run most binaries. Linux does not currently
1753	  support floating point hardware so you need to say Y here even if
1754	  your machine has an FPA or floating point co-processor podule.
1755
1756	  You may say N here if you are going to load the Acorn FPEmulator
1757	  early in the bootup.
1758
1759config FPE_NWFPE_XP
1760	bool "Support extended precision"
1761	depends on FPE_NWFPE
1762	help
1763	  Say Y to include 80-bit support in the kernel floating-point
1764	  emulator.  Otherwise, only 32 and 64-bit support is compiled in.
1765	  Note that gcc does not generate 80-bit operations by default,
1766	  so in most cases this option only enlarges the size of the
1767	  floating point emulator without any good reason.
1768
1769	  You almost surely want to say N here.
1770
1771config FPE_FASTFPE
1772	bool "FastFPE math emulation (EXPERIMENTAL)"
1773	depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
1774	help
1775	  Say Y here to include the FAST floating point emulator in the kernel.
1776	  This is an experimental much faster emulator which now also has full
1777	  precision for the mantissa.  It does not support any exceptions.
1778	  It is very simple, and approximately 3-6 times faster than NWFPE.
1779
1780	  It should be sufficient for most programs.  It may be not suitable
1781	  for scientific calculations, but you have to check this for yourself.
1782	  If you do not feel you need a faster FP emulation you should better
1783	  choose NWFPE.
1784
1785config VFP
1786	bool "VFP-format floating point maths"
1787	depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1788	help
1789	  Say Y to include VFP support code in the kernel. This is needed
1790	  if your hardware includes a VFP unit.
1791
1792	  Please see <file:Documentation/arm/vfp/release-notes.rst> for
1793	  release notes and additional status information.
1794
1795	  Say N if your target does not have VFP hardware.
1796
1797config VFPv3
1798	bool
1799	depends on VFP
1800	default y if CPU_V7
1801
1802config NEON
1803	bool "Advanced SIMD (NEON) Extension support"
1804	depends on VFPv3 && CPU_V7
1805	help
1806	  Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1807	  Extension.
1808
1809config KERNEL_MODE_NEON
1810	bool "Support for NEON in kernel mode"
1811	depends on NEON && AEABI
1812	help
1813	  Say Y to include support for NEON in kernel mode.
1814
1815endmenu
1816
1817menu "Power management options"
1818
1819source "kernel/power/Kconfig"
1820
1821config ARCH_SUSPEND_POSSIBLE
1822	depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
1823		CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
1824	def_bool y
1825
1826config ARM_CPU_SUSPEND
1827	def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
1828	depends on ARCH_SUSPEND_POSSIBLE
1829
1830config ARCH_HIBERNATION_POSSIBLE
1831	bool
1832	depends on MMU
1833	default y if ARCH_SUSPEND_POSSIBLE
1834
1835endmenu
1836
1837source "arch/arm/Kconfig.assembler"
1838