xref: /openbmc/linux/arch/arm/Kconfig (revision 65844828)
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	select ARCH_MULTI_V4_V5
349	select CPU_FA526 if !(CPU_SA110 || CPU_SA1100)
350
351config ARCH_MULTI_V4T
352	bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
353	depends on !ARCH_MULTI_V6_V7
354	select ARCH_MULTI_V4_V5
355	select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
356		CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
357		CPU_ARM925T || CPU_ARM940T)
358
359config ARCH_MULTI_V5
360	bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
361	depends on !ARCH_MULTI_V6_V7
362	select ARCH_MULTI_V4_V5
363	select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
364		CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
365		CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
366
367config ARCH_MULTI_V4_V5
368	bool
369
370config ARCH_MULTI_V6
371	bool "ARMv6 based platforms (ARM11)"
372	select ARCH_MULTI_V6_V7
373	select CPU_V6K
374
375config ARCH_MULTI_V7
376	bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
377	default y
378	select ARCH_MULTI_V6_V7
379	select CPU_V7
380	select HAVE_SMP
381
382config ARCH_MULTI_V6_V7
383	bool
384	select MIGHT_HAVE_CACHE_L2X0
385
386config ARCH_MULTI_CPU_AUTO
387	def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
388	select ARCH_MULTI_V5
389
390endmenu
391
392config ARCH_VIRT
393	bool "Dummy Virtual Machine"
394	depends on ARCH_MULTI_V7
395	select ARM_AMBA
396	select ARM_GIC
397	select ARM_GIC_V2M if PCI
398	select ARM_GIC_V3
399	select ARM_GIC_V3_ITS if PCI
400	select ARM_PSCI
401	select HAVE_ARM_ARCH_TIMER
402
403config ARCH_AIROHA
404	bool "Airoha SoC Support"
405	depends on ARCH_MULTI_V7
406	select ARM_AMBA
407	select ARM_GIC
408	select ARM_GIC_V3
409	select ARM_PSCI
410	select HAVE_ARM_ARCH_TIMER
411	help
412	  Support for Airoha EN7523 SoCs
413
414#
415# This is sorted alphabetically by mach-* pathname.  However, plat-*
416# Kconfigs may be included either alphabetically (according to the
417# plat- suffix) or along side the corresponding mach-* source.
418#
419source "arch/arm/mach-actions/Kconfig"
420
421source "arch/arm/mach-alpine/Kconfig"
422
423source "arch/arm/mach-artpec/Kconfig"
424
425source "arch/arm/mach-asm9260/Kconfig"
426
427source "arch/arm/mach-aspeed/Kconfig"
428
429source "arch/arm/mach-at91/Kconfig"
430
431source "arch/arm/mach-axxia/Kconfig"
432
433source "arch/arm/mach-bcm/Kconfig"
434
435source "arch/arm/mach-berlin/Kconfig"
436
437source "arch/arm/mach-clps711x/Kconfig"
438
439source "arch/arm/mach-cns3xxx/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-iop32x/Kconfig"
464
465source "arch/arm/mach-ixp4xx/Kconfig"
466
467source "arch/arm/mach-keystone/Kconfig"
468
469source "arch/arm/mach-lpc32xx/Kconfig"
470
471source "arch/arm/mach-mediatek/Kconfig"
472
473source "arch/arm/mach-meson/Kconfig"
474
475source "arch/arm/mach-milbeaut/Kconfig"
476
477source "arch/arm/mach-mmp/Kconfig"
478
479source "arch/arm/mach-moxart/Kconfig"
480
481source "arch/arm/mach-mstar/Kconfig"
482
483source "arch/arm/mach-mv78xx0/Kconfig"
484
485source "arch/arm/mach-mvebu/Kconfig"
486
487source "arch/arm/mach-mxs/Kconfig"
488
489source "arch/arm/mach-nomadik/Kconfig"
490
491source "arch/arm/mach-npcm/Kconfig"
492
493source "arch/arm/mach-nspire/Kconfig"
494
495source "arch/arm/mach-omap1/Kconfig"
496
497source "arch/arm/mach-omap2/Kconfig"
498
499source "arch/arm/mach-orion5x/Kconfig"
500
501source "arch/arm/mach-oxnas/Kconfig"
502
503source "arch/arm/mach-pxa/Kconfig"
504
505source "arch/arm/mach-qcom/Kconfig"
506
507source "arch/arm/mach-rda/Kconfig"
508
509source "arch/arm/mach-realtek/Kconfig"
510
511source "arch/arm/mach-rpc/Kconfig"
512
513source "arch/arm/mach-rockchip/Kconfig"
514
515source "arch/arm/mach-s3c/Kconfig"
516
517source "arch/arm/mach-s5pv210/Kconfig"
518
519source "arch/arm/mach-sa1100/Kconfig"
520
521source "arch/arm/mach-shmobile/Kconfig"
522
523source "arch/arm/mach-socfpga/Kconfig"
524
525source "arch/arm/mach-spear/Kconfig"
526
527source "arch/arm/mach-sti/Kconfig"
528
529source "arch/arm/mach-stm32/Kconfig"
530
531source "arch/arm/mach-sunplus/Kconfig"
532
533source "arch/arm/mach-sunxi/Kconfig"
534
535source "arch/arm/mach-tegra/Kconfig"
536
537source "arch/arm/mach-uniphier/Kconfig"
538
539source "arch/arm/mach-ux500/Kconfig"
540
541source "arch/arm/mach-versatile/Kconfig"
542
543source "arch/arm/mach-vt8500/Kconfig"
544
545source "arch/arm/mach-zynq/Kconfig"
546
547# ARMv7-M architecture
548config ARCH_LPC18XX
549	bool "NXP LPC18xx/LPC43xx"
550	depends on ARM_SINGLE_ARMV7M
551	select ARCH_HAS_RESET_CONTROLLER
552	select ARM_AMBA
553	select CLKSRC_LPC32XX
554	select PINCTRL
555	help
556	  Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
557	  high performance microcontrollers.
558
559config ARCH_MPS2
560	bool "ARM MPS2 platform"
561	depends on ARM_SINGLE_ARMV7M
562	select ARM_AMBA
563	select CLKSRC_MPS2
564	help
565	  Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
566	  with a range of available cores like Cortex-M3/M4/M7.
567
568	  Please, note that depends which Application Note is used memory map
569	  for the platform may vary, so adjustment of RAM base might be needed.
570
571# Definitions to make life easier
572config ARCH_ACORN
573	bool
574
575config PLAT_ORION
576	bool
577	select CLKSRC_MMIO
578	select GENERIC_IRQ_CHIP
579	select IRQ_DOMAIN
580
581config PLAT_ORION_LEGACY
582	bool
583	select PLAT_ORION
584
585config PLAT_VERSATILE
586	bool
587
588source "arch/arm/mm/Kconfig"
589
590config IWMMXT
591	bool "Enable iWMMXt support"
592	depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
593	default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
594	help
595	  Enable support for iWMMXt context switching at run time if
596	  running on a CPU that supports it.
597
598if !MMU
599source "arch/arm/Kconfig-nommu"
600endif
601
602config PJ4B_ERRATA_4742
603	bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
604	depends on CPU_PJ4B && MACH_ARMADA_370
605	default y
606	help
607	  When coming out of either a Wait for Interrupt (WFI) or a Wait for
608	  Event (WFE) IDLE states, a specific timing sensitivity exists between
609	  the retiring WFI/WFE instructions and the newly issued subsequent
610	  instructions.  This sensitivity can result in a CPU hang scenario.
611	  Workaround:
612	  The software must insert either a Data Synchronization Barrier (DSB)
613	  or Data Memory Barrier (DMB) command immediately after the WFI/WFE
614	  instruction
615
616config ARM_ERRATA_326103
617	bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
618	depends on CPU_V6
619	help
620	  Executing a SWP instruction to read-only memory does not set bit 11
621	  of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
622	  treat the access as a read, preventing a COW from occurring and
623	  causing the faulting task to livelock.
624
625config ARM_ERRATA_411920
626	bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
627	depends on CPU_V6 || CPU_V6K
628	help
629	  Invalidation of the Instruction Cache operation can
630	  fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
631	  It does not affect the MPCore. This option enables the ARM Ltd.
632	  recommended workaround.
633
634config ARM_ERRATA_430973
635	bool "ARM errata: Stale prediction on replaced interworking branch"
636	depends on CPU_V7
637	help
638	  This option enables the workaround for the 430973 Cortex-A8
639	  r1p* erratum. If a code sequence containing an ARM/Thumb
640	  interworking branch is replaced with another code sequence at the
641	  same virtual address, whether due to self-modifying code or virtual
642	  to physical address re-mapping, Cortex-A8 does not recover from the
643	  stale interworking branch prediction. This results in Cortex-A8
644	  executing the new code sequence in the incorrect ARM or Thumb state.
645	  The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
646	  and also flushes the branch target cache at every context switch.
647	  Note that setting specific bits in the ACTLR register may not be
648	  available in non-secure mode.
649
650config ARM_ERRATA_458693
651	bool "ARM errata: Processor deadlock when a false hazard is created"
652	depends on CPU_V7
653	depends on !ARCH_MULTIPLATFORM
654	help
655	  This option enables the workaround for the 458693 Cortex-A8 (r2p0)
656	  erratum. For very specific sequences of memory operations, it is
657	  possible for a hazard condition intended for a cache line to instead
658	  be incorrectly associated with a different cache line. This false
659	  hazard might then cause a processor deadlock. The workaround enables
660	  the L1 caching of the NEON accesses and disables the PLD instruction
661	  in the ACTLR register. Note that setting specific bits in the ACTLR
662	  register may not be available in non-secure mode.
663
664config ARM_ERRATA_460075
665	bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
666	depends on CPU_V7
667	depends on !ARCH_MULTIPLATFORM
668	help
669	  This option enables the workaround for the 460075 Cortex-A8 (r2p0)
670	  erratum. Any asynchronous access to the L2 cache may encounter a
671	  situation in which recent store transactions to the L2 cache are lost
672	  and overwritten with stale memory contents from external memory. The
673	  workaround disables the write-allocate mode for the L2 cache via the
674	  ACTLR register. Note that setting specific bits in the ACTLR register
675	  may not be available in non-secure mode.
676
677config ARM_ERRATA_742230
678	bool "ARM errata: DMB operation may be faulty"
679	depends on CPU_V7 && SMP
680	depends on !ARCH_MULTIPLATFORM
681	help
682	  This option enables the workaround for the 742230 Cortex-A9
683	  (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
684	  between two write operations may not ensure the correct visibility
685	  ordering of the two writes. This workaround sets a specific bit in
686	  the diagnostic register of the Cortex-A9 which causes the DMB
687	  instruction to behave as a DSB, ensuring the correct behaviour of
688	  the two writes.
689
690config ARM_ERRATA_742231
691	bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
692	depends on CPU_V7 && SMP
693	depends on !ARCH_MULTIPLATFORM
694	help
695	  This option enables the workaround for the 742231 Cortex-A9
696	  (r2p0..r2p2) erratum. Under certain conditions, specific to the
697	  Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
698	  accessing some data located in the same cache line, may get corrupted
699	  data due to bad handling of the address hazard when the line gets
700	  replaced from one of the CPUs at the same time as another CPU is
701	  accessing it. This workaround sets specific bits in the diagnostic
702	  register of the Cortex-A9 which reduces the linefill issuing
703	  capabilities of the processor.
704
705config ARM_ERRATA_643719
706	bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
707	depends on CPU_V7 && SMP
708	default y
709	help
710	  This option enables the workaround for the 643719 Cortex-A9 (prior to
711	  r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
712	  register returns zero when it should return one. The workaround
713	  corrects this value, ensuring cache maintenance operations which use
714	  it behave as intended and avoiding data corruption.
715
716config ARM_ERRATA_720789
717	bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
718	depends on CPU_V7
719	help
720	  This option enables the workaround for the 720789 Cortex-A9 (prior to
721	  r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
722	  broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
723	  As a consequence of this erratum, some TLB entries which should be
724	  invalidated are not, resulting in an incoherency in the system page
725	  tables. The workaround changes the TLB flushing routines to invalidate
726	  entries regardless of the ASID.
727
728config ARM_ERRATA_743622
729	bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
730	depends on CPU_V7
731	depends on !ARCH_MULTIPLATFORM
732	help
733	  This option enables the workaround for the 743622 Cortex-A9
734	  (r2p*) erratum. Under very rare conditions, a faulty
735	  optimisation in the Cortex-A9 Store Buffer may lead to data
736	  corruption. This workaround sets a specific bit in the diagnostic
737	  register of the Cortex-A9 which disables the Store Buffer
738	  optimisation, preventing the defect from occurring. This has no
739	  visible impact on the overall performance or power consumption of the
740	  processor.
741
742config ARM_ERRATA_751472
743	bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
744	depends on CPU_V7
745	depends on !ARCH_MULTIPLATFORM
746	help
747	  This option enables the workaround for the 751472 Cortex-A9 (prior
748	  to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
749	  completion of a following broadcasted operation if the second
750	  operation is received by a CPU before the ICIALLUIS has completed,
751	  potentially leading to corrupted entries in the cache or TLB.
752
753config ARM_ERRATA_754322
754	bool "ARM errata: possible faulty MMU translations following an ASID switch"
755	depends on CPU_V7
756	help
757	  This option enables the workaround for the 754322 Cortex-A9 (r2p*,
758	  r3p*) erratum. A speculative memory access may cause a page table walk
759	  which starts prior to an ASID switch but completes afterwards. This
760	  can populate the micro-TLB with a stale entry which may be hit with
761	  the new ASID. This workaround places two dsb instructions in the mm
762	  switching code so that no page table walks can cross the ASID switch.
763
764config ARM_ERRATA_754327
765	bool "ARM errata: no automatic Store Buffer drain"
766	depends on CPU_V7 && SMP
767	help
768	  This option enables the workaround for the 754327 Cortex-A9 (prior to
769	  r2p0) erratum. The Store Buffer does not have any automatic draining
770	  mechanism and therefore a livelock may occur if an external agent
771	  continuously polls a memory location waiting to observe an update.
772	  This workaround defines cpu_relax() as smp_mb(), preventing correctly
773	  written polling loops from denying visibility of updates to memory.
774
775config ARM_ERRATA_364296
776	bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
777	depends on CPU_V6
778	help
779	  This options enables the workaround for the 364296 ARM1136
780	  r0p2 erratum (possible cache data corruption with
781	  hit-under-miss enabled). It sets the undocumented bit 31 in
782	  the auxiliary control register and the FI bit in the control
783	  register, thus disabling hit-under-miss without putting the
784	  processor into full low interrupt latency mode. ARM11MPCore
785	  is not affected.
786
787config ARM_ERRATA_764369
788	bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
789	depends on CPU_V7 && SMP
790	help
791	  This option enables the workaround for erratum 764369
792	  affecting Cortex-A9 MPCore with two or more processors (all
793	  current revisions). Under certain timing circumstances, a data
794	  cache line maintenance operation by MVA targeting an Inner
795	  Shareable memory region may fail to proceed up to either the
796	  Point of Coherency or to the Point of Unification of the
797	  system. This workaround adds a DSB instruction before the
798	  relevant cache maintenance functions and sets a specific bit
799	  in the diagnostic control register of the SCU.
800
801config ARM_ERRATA_764319
802	bool "ARM errata: Read to DBGPRSR and DBGOSLSR may generate Undefined instruction"
803	depends on CPU_V7
804	help
805	  This option enables the workaround for the 764319 Cortex A-9 erratum.
806	  CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
807	  unexpected Undefined Instruction exception when the DBGSWENABLE
808	  external pin is set to 0, even when the CP14 accesses are performed
809	  from a privileged mode. This work around catches the exception in a
810	  way the kernel does not stop execution.
811
812config ARM_ERRATA_775420
813       bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
814       depends on CPU_V7
815       help
816	 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
817	 r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
818	 operation aborts with MMU exception, it might cause the processor
819	 to deadlock. This workaround puts DSB before executing ISB if
820	 an abort may occur on cache maintenance.
821
822config ARM_ERRATA_798181
823	bool "ARM errata: TLBI/DSB failure on Cortex-A15"
824	depends on CPU_V7 && SMP
825	help
826	  On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
827	  adequately shooting down all use of the old entries. This
828	  option enables the Linux kernel workaround for this erratum
829	  which sends an IPI to the CPUs that are running the same ASID
830	  as the one being invalidated.
831
832config ARM_ERRATA_773022
833	bool "ARM errata: incorrect instructions may be executed from loop buffer"
834	depends on CPU_V7
835	help
836	  This option enables the workaround for the 773022 Cortex-A15
837	  (up to r0p4) erratum. In certain rare sequences of code, the
838	  loop buffer may deliver incorrect instructions. This
839	  workaround disables the loop buffer to avoid the erratum.
840
841config ARM_ERRATA_818325_852422
842	bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
843	depends on CPU_V7
844	help
845	  This option enables the workaround for:
846	  - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
847	    instruction might deadlock.  Fixed in r0p1.
848	  - Cortex-A12 852422: Execution of a sequence of instructions might
849	    lead to either a data corruption or a CPU deadlock.  Not fixed in
850	    any Cortex-A12 cores yet.
851	  This workaround for all both errata involves setting bit[12] of the
852	  Feature Register. This bit disables an optimisation applied to a
853	  sequence of 2 instructions that use opposing condition codes.
854
855config ARM_ERRATA_821420
856	bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
857	depends on CPU_V7
858	help
859	  This option enables the workaround for the 821420 Cortex-A12
860	  (all revs) erratum. In very rare timing conditions, a sequence
861	  of VMOV to Core registers instructions, for which the second
862	  one is in the shadow of a branch or abort, can lead to a
863	  deadlock when the VMOV instructions are issued out-of-order.
864
865config ARM_ERRATA_825619
866	bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
867	depends on CPU_V7
868	help
869	  This option enables the workaround for the 825619 Cortex-A12
870	  (all revs) erratum. Within rare timing constraints, executing a
871	  DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
872	  and Device/Strongly-Ordered loads and stores might cause deadlock
873
874config ARM_ERRATA_857271
875	bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
876	depends on CPU_V7
877	help
878	  This option enables the workaround for the 857271 Cortex-A12
879	  (all revs) erratum. Under very rare timing conditions, the CPU might
880	  hang. The workaround is expected to have a < 1% performance impact.
881
882config ARM_ERRATA_852421
883	bool "ARM errata: A17: DMB ST might fail to create order between stores"
884	depends on CPU_V7
885	help
886	  This option enables the workaround for the 852421 Cortex-A17
887	  (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
888	  execution of a DMB ST instruction might fail to properly order
889	  stores from GroupA and stores from GroupB.
890
891config ARM_ERRATA_852423
892	bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
893	depends on CPU_V7
894	help
895	  This option enables the workaround for:
896	  - Cortex-A17 852423: Execution of a sequence of instructions might
897	    lead to either a data corruption or a CPU deadlock.  Not fixed in
898	    any Cortex-A17 cores yet.
899	  This is identical to Cortex-A12 erratum 852422.  It is a separate
900	  config option from the A12 erratum due to the way errata are checked
901	  for and handled.
902
903config ARM_ERRATA_857272
904	bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
905	depends on CPU_V7
906	help
907	  This option enables the workaround for the 857272 Cortex-A17 erratum.
908	  This erratum is not known to be fixed in any A17 revision.
909	  This is identical to Cortex-A12 erratum 857271.  It is a separate
910	  config option from the A12 erratum due to the way errata are checked
911	  for and handled.
912
913endmenu
914
915source "arch/arm/common/Kconfig"
916
917menu "Bus support"
918
919config ISA
920	bool
921	help
922	  Find out whether you have ISA slots on your motherboard.  ISA is the
923	  name of a bus system, i.e. the way the CPU talks to the other stuff
924	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
925	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
926	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
927
928# Select ISA DMA interface
929config ISA_DMA_API
930	bool
931
932config PCI_NANOENGINE
933	bool "BSE nanoEngine PCI support"
934	depends on SA1100_NANOENGINE
935	help
936	  Enable PCI on the BSE nanoEngine board.
937
938config ARM_ERRATA_814220
939	bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
940	depends on CPU_V7
941	help
942	  The v7 ARM states that all cache and branch predictor maintenance
943	  operations that do not specify an address execute, relative to
944	  each other, in program order.
945	  However, because of this erratum, an L2 set/way cache maintenance
946	  operation can overtake an L1 set/way cache maintenance operation.
947	  This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
948	  r0p4, r0p5.
949
950endmenu
951
952menu "Kernel Features"
953
954config HAVE_SMP
955	bool
956	help
957	  This option should be selected by machines which have an SMP-
958	  capable CPU.
959
960	  The only effect of this option is to make the SMP-related
961	  options available to the user for configuration.
962
963config SMP
964	bool "Symmetric Multi-Processing"
965	depends on CPU_V6K || CPU_V7
966	depends on HAVE_SMP
967	depends on MMU || ARM_MPU
968	select IRQ_WORK
969	help
970	  This enables support for systems with more than one CPU. If you have
971	  a system with only one CPU, say N. If you have a system with more
972	  than one CPU, say Y.
973
974	  If you say N here, the kernel will run on uni- and multiprocessor
975	  machines, but will use only one CPU of a multiprocessor machine. If
976	  you say Y here, the kernel will run on many, but not all,
977	  uniprocessor machines. On a uniprocessor machine, the kernel
978	  will run faster if you say N here.
979
980	  See also <file:Documentation/x86/i386/IO-APIC.rst>,
981	  <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
982	  <http://tldp.org/HOWTO/SMP-HOWTO.html>.
983
984	  If you don't know what to do here, say N.
985
986config SMP_ON_UP
987	bool "Allow booting SMP kernel on uniprocessor systems"
988	depends on SMP && MMU
989	default y
990	help
991	  SMP kernels contain instructions which fail on non-SMP processors.
992	  Enabling this option allows the kernel to modify itself to make
993	  these instructions safe.  Disabling it allows about 1K of space
994	  savings.
995
996	  If you don't know what to do here, say Y.
997
998
999config CURRENT_POINTER_IN_TPIDRURO
1000	def_bool y
1001	depends on CPU_32v6K && !CPU_V6
1002
1003config IRQSTACKS
1004	def_bool y
1005	select HAVE_IRQ_EXIT_ON_IRQ_STACK
1006	select HAVE_SOFTIRQ_ON_OWN_STACK
1007
1008config ARM_CPU_TOPOLOGY
1009	bool "Support cpu topology definition"
1010	depends on SMP && CPU_V7
1011	default y
1012	help
1013	  Support ARM cpu topology definition. The MPIDR register defines
1014	  affinity between processors which is then used to describe the cpu
1015	  topology of an ARM System.
1016
1017config SCHED_MC
1018	bool "Multi-core scheduler support"
1019	depends on ARM_CPU_TOPOLOGY
1020	help
1021	  Multi-core scheduler support improves the CPU scheduler's decision
1022	  making when dealing with multi-core CPU chips at a cost of slightly
1023	  increased overhead in some places. If unsure say N here.
1024
1025config SCHED_SMT
1026	bool "SMT scheduler support"
1027	depends on ARM_CPU_TOPOLOGY
1028	help
1029	  Improves the CPU scheduler's decision making when dealing with
1030	  MultiThreading at a cost of slightly increased overhead in some
1031	  places. If unsure say N here.
1032
1033config HAVE_ARM_SCU
1034	bool
1035	help
1036	  This option enables support for the ARM snoop control unit
1037
1038config HAVE_ARM_ARCH_TIMER
1039	bool "Architected timer support"
1040	depends on CPU_V7
1041	select ARM_ARCH_TIMER
1042	help
1043	  This option enables support for the ARM architected timer
1044
1045config HAVE_ARM_TWD
1046	bool
1047	help
1048	  This options enables support for the ARM timer and watchdog unit
1049
1050config MCPM
1051	bool "Multi-Cluster Power Management"
1052	depends on CPU_V7 && SMP
1053	help
1054	  This option provides the common power management infrastructure
1055	  for (multi-)cluster based systems, such as big.LITTLE based
1056	  systems.
1057
1058config MCPM_QUAD_CLUSTER
1059	bool
1060	depends on MCPM
1061	help
1062	  To avoid wasting resources unnecessarily, MCPM only supports up
1063	  to 2 clusters by default.
1064	  Platforms with 3 or 4 clusters that use MCPM must select this
1065	  option to allow the additional clusters to be managed.
1066
1067config BIG_LITTLE
1068	bool "big.LITTLE support (Experimental)"
1069	depends on CPU_V7 && SMP
1070	select MCPM
1071	help
1072	  This option enables support selections for the big.LITTLE
1073	  system architecture.
1074
1075config BL_SWITCHER
1076	bool "big.LITTLE switcher support"
1077	depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
1078	select CPU_PM
1079	help
1080	  The big.LITTLE "switcher" provides the core functionality to
1081	  transparently handle transition between a cluster of A15's
1082	  and a cluster of A7's in a big.LITTLE system.
1083
1084config BL_SWITCHER_DUMMY_IF
1085	tristate "Simple big.LITTLE switcher user interface"
1086	depends on BL_SWITCHER && DEBUG_KERNEL
1087	help
1088	  This is a simple and dummy char dev interface to control
1089	  the big.LITTLE switcher core code.  It is meant for
1090	  debugging purposes only.
1091
1092choice
1093	prompt "Memory split"
1094	depends on MMU
1095	default VMSPLIT_3G
1096	help
1097	  Select the desired split between kernel and user memory.
1098
1099	  If you are not absolutely sure what you are doing, leave this
1100	  option alone!
1101
1102	config VMSPLIT_3G
1103		bool "3G/1G user/kernel split"
1104	config VMSPLIT_3G_OPT
1105		depends on !ARM_LPAE
1106		bool "3G/1G user/kernel split (for full 1G low memory)"
1107	config VMSPLIT_2G
1108		bool "2G/2G user/kernel split"
1109	config VMSPLIT_1G
1110		bool "1G/3G user/kernel split"
1111endchoice
1112
1113config PAGE_OFFSET
1114	hex
1115	default PHYS_OFFSET if !MMU
1116	default 0x40000000 if VMSPLIT_1G
1117	default 0x80000000 if VMSPLIT_2G
1118	default 0xB0000000 if VMSPLIT_3G_OPT
1119	default 0xC0000000
1120
1121config KASAN_SHADOW_OFFSET
1122	hex
1123	depends on KASAN
1124	default 0x1f000000 if PAGE_OFFSET=0x40000000
1125	default 0x5f000000 if PAGE_OFFSET=0x80000000
1126	default 0x9f000000 if PAGE_OFFSET=0xC0000000
1127	default 0x8f000000 if PAGE_OFFSET=0xB0000000
1128	default 0xffffffff
1129
1130config NR_CPUS
1131	int "Maximum number of CPUs (2-32)"
1132	range 2 16 if DEBUG_KMAP_LOCAL
1133	range 2 32 if !DEBUG_KMAP_LOCAL
1134	depends on SMP
1135	default "4"
1136	help
1137	  The maximum number of CPUs that the kernel can support.
1138	  Up to 32 CPUs can be supported, or up to 16 if kmap_local()
1139	  debugging is enabled, which uses half of the per-CPU fixmap
1140	  slots as guard regions.
1141
1142config HOTPLUG_CPU
1143	bool "Support for hot-pluggable CPUs"
1144	depends on SMP
1145	select GENERIC_IRQ_MIGRATION
1146	help
1147	  Say Y here to experiment with turning CPUs off and on.  CPUs
1148	  can be controlled through /sys/devices/system/cpu.
1149
1150config ARM_PSCI
1151	bool "Support for the ARM Power State Coordination Interface (PSCI)"
1152	depends on HAVE_ARM_SMCCC
1153	select ARM_PSCI_FW
1154	help
1155	  Say Y here if you want Linux to communicate with system firmware
1156	  implementing the PSCI specification for CPU-centric power
1157	  management operations described in ARM document number ARM DEN
1158	  0022A ("Power State Coordination Interface System Software on
1159	  ARM processors").
1160
1161config HZ_FIXED
1162	int
1163	default 128 if SOC_AT91RM9200
1164	default 0
1165
1166choice
1167	depends on HZ_FIXED = 0
1168	prompt "Timer frequency"
1169
1170config HZ_100
1171	bool "100 Hz"
1172
1173config HZ_200
1174	bool "200 Hz"
1175
1176config HZ_250
1177	bool "250 Hz"
1178
1179config HZ_300
1180	bool "300 Hz"
1181
1182config HZ_500
1183	bool "500 Hz"
1184
1185config HZ_1000
1186	bool "1000 Hz"
1187
1188endchoice
1189
1190config HZ
1191	int
1192	default HZ_FIXED if HZ_FIXED != 0
1193	default 100 if HZ_100
1194	default 200 if HZ_200
1195	default 250 if HZ_250
1196	default 300 if HZ_300
1197	default 500 if HZ_500
1198	default 1000
1199
1200config SCHED_HRTICK
1201	def_bool HIGH_RES_TIMERS
1202
1203config THUMB2_KERNEL
1204	bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1205	depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1206	default y if CPU_THUMBONLY
1207	select ARM_UNWIND
1208	help
1209	  By enabling this option, the kernel will be compiled in
1210	  Thumb-2 mode.
1211
1212	  If unsure, say N.
1213
1214config ARM_PATCH_IDIV
1215	bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
1216	depends on CPU_32v7
1217	default y
1218	help
1219	  The ARM compiler inserts calls to __aeabi_idiv() and
1220	  __aeabi_uidiv() when it needs to perform division on signed
1221	  and unsigned integers. Some v7 CPUs have support for the sdiv
1222	  and udiv instructions that can be used to implement those
1223	  functions.
1224
1225	  Enabling this option allows the kernel to modify itself to
1226	  replace the first two instructions of these library functions
1227	  with the sdiv or udiv plus "bx lr" instructions when the CPU
1228	  it is running on supports them. Typically this will be faster
1229	  and less power intensive than running the original library
1230	  code to do integer division.
1231
1232config AEABI
1233	bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1234		!CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1235	default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
1236	help
1237	  This option allows for the kernel to be compiled using the latest
1238	  ARM ABI (aka EABI).  This is only useful if you are using a user
1239	  space environment that is also compiled with EABI.
1240
1241	  Since there are major incompatibilities between the legacy ABI and
1242	  EABI, especially with regard to structure member alignment, this
1243	  option also changes the kernel syscall calling convention to
1244	  disambiguate both ABIs and allow for backward compatibility support
1245	  (selected with CONFIG_OABI_COMPAT).
1246
1247	  To use this you need GCC version 4.0.0 or later.
1248
1249config OABI_COMPAT
1250	bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1251	depends on AEABI && !THUMB2_KERNEL
1252	help
1253	  This option preserves the old syscall interface along with the
1254	  new (ARM EABI) one. It also provides a compatibility layer to
1255	  intercept syscalls that have structure arguments which layout
1256	  in memory differs between the legacy ABI and the new ARM EABI
1257	  (only for non "thumb" binaries). This option adds a tiny
1258	  overhead to all syscalls and produces a slightly larger kernel.
1259
1260	  The seccomp filter system will not be available when this is
1261	  selected, since there is no way yet to sensibly distinguish
1262	  between calling conventions during filtering.
1263
1264	  If you know you'll be using only pure EABI user space then you
1265	  can say N here. If this option is not selected and you attempt
1266	  to execute a legacy ABI binary then the result will be
1267	  UNPREDICTABLE (in fact it can be predicted that it won't work
1268	  at all). If in doubt say N.
1269
1270config ARCH_SELECT_MEMORY_MODEL
1271	def_bool y
1272
1273config ARCH_FLATMEM_ENABLE
1274	def_bool !(ARCH_RPC || ARCH_SA1100)
1275
1276config ARCH_SPARSEMEM_ENABLE
1277	def_bool !ARCH_FOOTBRIDGE
1278	select SPARSEMEM_STATIC if SPARSEMEM
1279
1280config HIGHMEM
1281	bool "High Memory Support"
1282	depends on MMU
1283	select KMAP_LOCAL
1284	select KMAP_LOCAL_NON_LINEAR_PTE_ARRAY
1285	help
1286	  The address space of ARM processors is only 4 Gigabytes large
1287	  and it has to accommodate user address space, kernel address
1288	  space as well as some memory mapped IO. That means that, if you
1289	  have a large amount of physical memory and/or IO, not all of the
1290	  memory can be "permanently mapped" by the kernel. The physical
1291	  memory that is not permanently mapped is called "high memory".
1292
1293	  Depending on the selected kernel/user memory split, minimum
1294	  vmalloc space and actual amount of RAM, you may not need this
1295	  option which should result in a slightly faster kernel.
1296
1297	  If unsure, say n.
1298
1299config HIGHPTE
1300	bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1301	depends on HIGHMEM
1302	default y
1303	help
1304	  The VM uses one page of physical memory for each page table.
1305	  For systems with a lot of processes, this can use a lot of
1306	  precious low memory, eventually leading to low memory being
1307	  consumed by page tables.  Setting this option will allow
1308	  user-space 2nd level page tables to reside in high memory.
1309
1310config CPU_SW_DOMAIN_PAN
1311	bool "Enable use of CPU domains to implement privileged no-access"
1312	depends on MMU && !ARM_LPAE
1313	default y
1314	help
1315	  Increase kernel security by ensuring that normal kernel accesses
1316	  are unable to access userspace addresses.  This can help prevent
1317	  use-after-free bugs becoming an exploitable privilege escalation
1318	  by ensuring that magic values (such as LIST_POISON) will always
1319	  fault when dereferenced.
1320
1321	  CPUs with low-vector mappings use a best-efforts implementation.
1322	  Their lower 1MB needs to remain accessible for the vectors, but
1323	  the remainder of userspace will become appropriately inaccessible.
1324
1325config HW_PERF_EVENTS
1326	def_bool y
1327	depends on ARM_PMU
1328
1329config ARM_MODULE_PLTS
1330	bool "Use PLTs to allow module memory to spill over into vmalloc area"
1331	depends on MODULES
1332	select KASAN_VMALLOC if KASAN
1333	default y
1334	help
1335	  Allocate PLTs when loading modules so that jumps and calls whose
1336	  targets are too far away for their relative offsets to be encoded
1337	  in the instructions themselves can be bounced via veneers in the
1338	  module's PLT. This allows modules to be allocated in the generic
1339	  vmalloc area after the dedicated module memory area has been
1340	  exhausted. The modules will use slightly more memory, but after
1341	  rounding up to page size, the actual memory footprint is usually
1342	  the same.
1343
1344	  Disabling this is usually safe for small single-platform
1345	  configurations. If unsure, say y.
1346
1347config ARCH_FORCE_MAX_ORDER
1348	int "Maximum zone order"
1349	default "12" if SOC_AM33XX
1350	default "9" if SA1111
1351	default "11"
1352	help
1353	  The kernel memory allocator divides physically contiguous memory
1354	  blocks into "zones", where each zone is a power of two number of
1355	  pages.  This option selects the largest power of two that the kernel
1356	  keeps in the memory allocator.  If you need to allocate very large
1357	  blocks of physically contiguous memory, then you may need to
1358	  increase this value.
1359
1360	  This config option is actually maximum order plus one. For example,
1361	  a value of 11 means that the largest free memory block is 2^10 pages.
1362
1363config ALIGNMENT_TRAP
1364	def_bool CPU_CP15_MMU
1365	select HAVE_PROC_CPU if PROC_FS
1366	help
1367	  ARM processors cannot fetch/store information which is not
1368	  naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1369	  address divisible by 4. On 32-bit ARM processors, these non-aligned
1370	  fetch/store instructions will be emulated in software if you say
1371	  here, which has a severe performance impact. This is necessary for
1372	  correct operation of some network protocols. With an IP-only
1373	  configuration it is safe to say N, otherwise say Y.
1374
1375config UACCESS_WITH_MEMCPY
1376	bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1377	depends on MMU
1378	default y if CPU_FEROCEON
1379	help
1380	  Implement faster copy_to_user and clear_user methods for CPU
1381	  cores where a 8-word STM instruction give significantly higher
1382	  memory write throughput than a sequence of individual 32bit stores.
1383
1384	  A possible side effect is a slight increase in scheduling latency
1385	  between threads sharing the same address space if they invoke
1386	  such copy operations with large buffers.
1387
1388	  However, if the CPU data cache is using a write-allocate mode,
1389	  this option is unlikely to provide any performance gain.
1390
1391config PARAVIRT
1392	bool "Enable paravirtualization code"
1393	help
1394	  This changes the kernel so it can modify itself when it is run
1395	  under a hypervisor, potentially improving performance significantly
1396	  over full virtualization.
1397
1398config PARAVIRT_TIME_ACCOUNTING
1399	bool "Paravirtual steal time accounting"
1400	select PARAVIRT
1401	help
1402	  Select this option to enable fine granularity task steal time
1403	  accounting. Time spent executing other tasks in parallel with
1404	  the current vCPU is discounted from the vCPU power. To account for
1405	  that, there can be a small performance impact.
1406
1407	  If in doubt, say N here.
1408
1409config XEN_DOM0
1410	def_bool y
1411	depends on XEN
1412
1413config XEN
1414	bool "Xen guest support on ARM"
1415	depends on ARM && AEABI && OF
1416	depends on CPU_V7 && !CPU_V6
1417	depends on !GENERIC_ATOMIC64
1418	depends on MMU
1419	select ARCH_DMA_ADDR_T_64BIT
1420	select ARM_PSCI
1421	select SWIOTLB
1422	select SWIOTLB_XEN
1423	select PARAVIRT
1424	help
1425	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1426
1427config CC_HAVE_STACKPROTECTOR_TLS
1428	def_bool $(cc-option,-mtp=cp15 -mstack-protector-guard=tls -mstack-protector-guard-offset=0)
1429
1430config STACKPROTECTOR_PER_TASK
1431	bool "Use a unique stack canary value for each task"
1432	depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA
1433	depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS
1434	select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS
1435	default y
1436	help
1437	  Due to the fact that GCC uses an ordinary symbol reference from
1438	  which to load the value of the stack canary, this value can only
1439	  change at reboot time on SMP systems, and all tasks running in the
1440	  kernel's address space are forced to use the same canary value for
1441	  the entire duration that the system is up.
1442
1443	  Enable this option to switch to a different method that uses a
1444	  different canary value for each task.
1445
1446endmenu
1447
1448menu "Boot options"
1449
1450config USE_OF
1451	bool "Flattened Device Tree support"
1452	select IRQ_DOMAIN
1453	select OF
1454	help
1455	  Include support for flattened device tree machine descriptions.
1456
1457config ATAGS
1458	bool "Support for the traditional ATAGS boot data passing"
1459	default y
1460	help
1461	  This is the traditional way of passing data to the kernel at boot
1462	  time. If you are solely relying on the flattened device tree (or
1463	  the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1464	  to remove ATAGS support from your kernel binary.
1465
1466config UNUSED_BOARD_FILES
1467	bool "Board support for machines without known users"
1468	depends on ATAGS
1469	help
1470	  Most ATAGS based board files are completely unused and are
1471	  scheduled for removal in early 2023, and left out of kernels
1472	  by default now.  If you are using a board file that is marked
1473	  as unused, turn on this option to build support into the kernel.
1474
1475	  To keep support for your individual board from being removed,
1476	  send a reply to the email discussion at
1477	  https://lore.kernel.org/all/CAK8P3a0Z9vGEQbVRBo84bSyPFM-LF+hs5w8ZA51g2Z+NsdtDQA@mail.gmail.com/
1478
1479config DEPRECATED_PARAM_STRUCT
1480	bool "Provide old way to pass kernel parameters"
1481	depends on ATAGS
1482	help
1483	  This was deprecated in 2001 and announced to live on for 5 years.
1484	  Some old boot loaders still use this way.
1485
1486# Compressed boot loader in ROM.  Yes, we really want to ask about
1487# TEXT and BSS so we preserve their values in the config files.
1488config ZBOOT_ROM_TEXT
1489	hex "Compressed ROM boot loader base address"
1490	default 0x0
1491	help
1492	  The physical address at which the ROM-able zImage is to be
1493	  placed in the target.  Platforms which normally make use of
1494	  ROM-able zImage formats normally set this to a suitable
1495	  value in their defconfig file.
1496
1497	  If ZBOOT_ROM is not enabled, this has no effect.
1498
1499config ZBOOT_ROM_BSS
1500	hex "Compressed ROM boot loader BSS address"
1501	default 0x0
1502	help
1503	  The base address of an area of read/write memory in the target
1504	  for the ROM-able zImage which must be available while the
1505	  decompressor is running. It must be large enough to hold the
1506	  entire decompressed kernel plus an additional 128 KiB.
1507	  Platforms which normally make use of ROM-able zImage formats
1508	  normally set this to a suitable value in their defconfig file.
1509
1510	  If ZBOOT_ROM is not enabled, this has no effect.
1511
1512config ZBOOT_ROM
1513	bool "Compressed boot loader in ROM/flash"
1514	depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1515	depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1516	help
1517	  Say Y here if you intend to execute your compressed kernel image
1518	  (zImage) directly from ROM or flash.  If unsure, say N.
1519
1520config ARM_APPENDED_DTB
1521	bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1522	depends on OF
1523	help
1524	  With this option, the boot code will look for a device tree binary
1525	  (DTB) appended to zImage
1526	  (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1527
1528	  This is meant as a backward compatibility convenience for those
1529	  systems with a bootloader that can't be upgraded to accommodate
1530	  the documented boot protocol using a device tree.
1531
1532	  Beware that there is very little in terms of protection against
1533	  this option being confused by leftover garbage in memory that might
1534	  look like a DTB header after a reboot if no actual DTB is appended
1535	  to zImage.  Do not leave this option active in a production kernel
1536	  if you don't intend to always append a DTB.  Proper passing of the
1537	  location into r2 of a bootloader provided DTB is always preferable
1538	  to this option.
1539
1540config ARM_ATAG_DTB_COMPAT
1541	bool "Supplement the appended DTB with traditional ATAG information"
1542	depends on ARM_APPENDED_DTB
1543	help
1544	  Some old bootloaders can't be updated to a DTB capable one, yet
1545	  they provide ATAGs with memory configuration, the ramdisk address,
1546	  the kernel cmdline string, etc.  Such information is dynamically
1547	  provided by the bootloader and can't always be stored in a static
1548	  DTB.  To allow a device tree enabled kernel to be used with such
1549	  bootloaders, this option allows zImage to extract the information
1550	  from the ATAG list and store it at run time into the appended DTB.
1551
1552choice
1553	prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1554	default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1555
1556config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1557	bool "Use bootloader kernel arguments if available"
1558	help
1559	  Uses the command-line options passed by the boot loader instead of
1560	  the device tree bootargs property. If the boot loader doesn't provide
1561	  any, the device tree bootargs property will be used.
1562
1563config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1564	bool "Extend with bootloader kernel arguments"
1565	help
1566	  The command-line arguments provided by the boot loader will be
1567	  appended to the the device tree bootargs property.
1568
1569endchoice
1570
1571config CMDLINE
1572	string "Default kernel command string"
1573	default ""
1574	help
1575	  On some architectures (e.g. CATS), there is currently no way
1576	  for the boot loader to pass arguments to the kernel. For these
1577	  architectures, you should supply some command-line options at build
1578	  time by entering them here. As a minimum, you should specify the
1579	  memory size and the root device (e.g., mem=64M root=/dev/nfs).
1580
1581choice
1582	prompt "Kernel command line type" if CMDLINE != ""
1583	default CMDLINE_FROM_BOOTLOADER
1584
1585config CMDLINE_FROM_BOOTLOADER
1586	bool "Use bootloader kernel arguments if available"
1587	help
1588	  Uses the command-line options passed by the boot loader. If
1589	  the boot loader doesn't provide any, the default kernel command
1590	  string provided in CMDLINE will be used.
1591
1592config CMDLINE_EXTEND
1593	bool "Extend bootloader kernel arguments"
1594	help
1595	  The command-line arguments provided by the boot loader will be
1596	  appended to the default kernel command string.
1597
1598config CMDLINE_FORCE
1599	bool "Always use the default kernel command string"
1600	help
1601	  Always use the default kernel command string, even if the boot
1602	  loader passes other arguments to the kernel.
1603	  This is useful if you cannot or don't want to change the
1604	  command-line options your boot loader passes to the kernel.
1605endchoice
1606
1607config XIP_KERNEL
1608	bool "Kernel Execute-In-Place from ROM"
1609	depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
1610	depends on !ARM_PATCH_IDIV && !ARM_PATCH_PHYS_VIRT && !SMP_ON_UP
1611	help
1612	  Execute-In-Place allows the kernel to run from non-volatile storage
1613	  directly addressable by the CPU, such as NOR flash. This saves RAM
1614	  space since the text section of the kernel is not loaded from flash
1615	  to RAM.  Read-write sections, such as the data section and stack,
1616	  are still copied to RAM.  The XIP kernel is not compressed since
1617	  it has to run directly from flash, so it will take more space to
1618	  store it.  The flash address used to link the kernel object files,
1619	  and for storing it, is configuration dependent. Therefore, if you
1620	  say Y here, you must know the proper physical address where to
1621	  store the kernel image depending on your own flash memory usage.
1622
1623	  Also note that the make target becomes "make xipImage" rather than
1624	  "make zImage" or "make Image".  The final kernel binary to put in
1625	  ROM memory will be arch/arm/boot/xipImage.
1626
1627	  If unsure, say N.
1628
1629config XIP_PHYS_ADDR
1630	hex "XIP Kernel Physical Location"
1631	depends on XIP_KERNEL
1632	default "0x00080000"
1633	help
1634	  This is the physical address in your flash memory the kernel will
1635	  be linked for and stored to.  This address is dependent on your
1636	  own flash usage.
1637
1638config XIP_DEFLATED_DATA
1639	bool "Store kernel .data section compressed in ROM"
1640	depends on XIP_KERNEL
1641	select ZLIB_INFLATE
1642	help
1643	  Before the kernel is actually executed, its .data section has to be
1644	  copied to RAM from ROM. This option allows for storing that data
1645	  in compressed form and decompressed to RAM rather than merely being
1646	  copied, saving some precious ROM space. A possible drawback is a
1647	  slightly longer boot delay.
1648
1649config KEXEC
1650	bool "Kexec system call (EXPERIMENTAL)"
1651	depends on (!SMP || PM_SLEEP_SMP)
1652	depends on MMU
1653	select KEXEC_CORE
1654	help
1655	  kexec is a system call that implements the ability to shutdown your
1656	  current kernel, and to start another kernel.  It is like a reboot
1657	  but it is independent of the system firmware.   And like a reboot
1658	  you can start any kernel with it, not just Linux.
1659
1660	  It is an ongoing process to be certain the hardware in a machine
1661	  is properly shutdown, so do not be surprised if this code does not
1662	  initially work for you.
1663
1664config ATAGS_PROC
1665	bool "Export atags in procfs"
1666	depends on ATAGS && KEXEC
1667	default y
1668	help
1669	  Should the atags used to boot the kernel be exported in an "atags"
1670	  file in procfs. Useful with kexec.
1671
1672config CRASH_DUMP
1673	bool "Build kdump crash kernel (EXPERIMENTAL)"
1674	help
1675	  Generate crash dump after being started by kexec. This should
1676	  be normally only set in special crash dump kernels which are
1677	  loaded in the main kernel with kexec-tools into a specially
1678	  reserved region and then later executed after a crash by
1679	  kdump/kexec. The crash dump kernel must be compiled to a
1680	  memory address not used by the main kernel
1681
1682	  For more details see Documentation/admin-guide/kdump/kdump.rst
1683
1684config AUTO_ZRELADDR
1685	bool "Auto calculation of the decompressed kernel image address" if !ARCH_MULTIPLATFORM
1686	default !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
1687	help
1688	  ZRELADDR is the physical address where the decompressed kernel
1689	  image will be placed. If AUTO_ZRELADDR is selected, the address
1690	  will be determined at run-time, either by masking the current IP
1691	  with 0xf8000000, or, if invalid, from the DTB passed in r2.
1692	  This assumes the zImage being placed in the first 128MB from
1693	  start of memory.
1694
1695config EFI_STUB
1696	bool
1697
1698config EFI
1699	bool "UEFI runtime support"
1700	depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
1701	select UCS2_STRING
1702	select EFI_PARAMS_FROM_FDT
1703	select EFI_STUB
1704	select EFI_GENERIC_STUB
1705	select EFI_RUNTIME_WRAPPERS
1706	help
1707	  This option provides support for runtime services provided
1708	  by UEFI firmware (such as non-volatile variables, realtime
1709	  clock, and platform reset). A UEFI stub is also provided to
1710	  allow the kernel to be booted as an EFI application. This
1711	  is only useful for kernels that may run on systems that have
1712	  UEFI firmware.
1713
1714config DMI
1715	bool "Enable support for SMBIOS (DMI) tables"
1716	depends on EFI
1717	default y
1718	help
1719	  This enables SMBIOS/DMI feature for systems.
1720
1721	  This option is only useful on systems that have UEFI firmware.
1722	  However, even with this option, the resultant kernel should
1723	  continue to boot on existing non-UEFI platforms.
1724
1725	  NOTE: This does *NOT* enable or encourage the use of DMI quirks,
1726	  i.e., the the practice of identifying the platform via DMI to
1727	  decide whether certain workarounds for buggy hardware and/or
1728	  firmware need to be enabled. This would require the DMI subsystem
1729	  to be enabled much earlier than we do on ARM, which is non-trivial.
1730
1731endmenu
1732
1733menu "CPU Power Management"
1734
1735source "drivers/cpufreq/Kconfig"
1736
1737source "drivers/cpuidle/Kconfig"
1738
1739endmenu
1740
1741menu "Floating point emulation"
1742
1743comment "At least one emulation must be selected"
1744
1745config FPE_NWFPE
1746	bool "NWFPE math emulation"
1747	depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
1748	help
1749	  Say Y to include the NWFPE floating point emulator in the kernel.
1750	  This is necessary to run most binaries. Linux does not currently
1751	  support floating point hardware so you need to say Y here even if
1752	  your machine has an FPA or floating point co-processor podule.
1753
1754	  You may say N here if you are going to load the Acorn FPEmulator
1755	  early in the bootup.
1756
1757config FPE_NWFPE_XP
1758	bool "Support extended precision"
1759	depends on FPE_NWFPE
1760	help
1761	  Say Y to include 80-bit support in the kernel floating-point
1762	  emulator.  Otherwise, only 32 and 64-bit support is compiled in.
1763	  Note that gcc does not generate 80-bit operations by default,
1764	  so in most cases this option only enlarges the size of the
1765	  floating point emulator without any good reason.
1766
1767	  You almost surely want to say N here.
1768
1769config FPE_FASTFPE
1770	bool "FastFPE math emulation (EXPERIMENTAL)"
1771	depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
1772	help
1773	  Say Y here to include the FAST floating point emulator in the kernel.
1774	  This is an experimental much faster emulator which now also has full
1775	  precision for the mantissa.  It does not support any exceptions.
1776	  It is very simple, and approximately 3-6 times faster than NWFPE.
1777
1778	  It should be sufficient for most programs.  It may be not suitable
1779	  for scientific calculations, but you have to check this for yourself.
1780	  If you do not feel you need a faster FP emulation you should better
1781	  choose NWFPE.
1782
1783config VFP
1784	bool "VFP-format floating point maths"
1785	depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1786	help
1787	  Say Y to include VFP support code in the kernel. This is needed
1788	  if your hardware includes a VFP unit.
1789
1790	  Please see <file:Documentation/arm/vfp/release-notes.rst> for
1791	  release notes and additional status information.
1792
1793	  Say N if your target does not have VFP hardware.
1794
1795config VFPv3
1796	bool
1797	depends on VFP
1798	default y if CPU_V7
1799
1800config NEON
1801	bool "Advanced SIMD (NEON) Extension support"
1802	depends on VFPv3 && CPU_V7
1803	help
1804	  Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1805	  Extension.
1806
1807config KERNEL_MODE_NEON
1808	bool "Support for NEON in kernel mode"
1809	depends on NEON && AEABI
1810	help
1811	  Say Y to include support for NEON in kernel mode.
1812
1813endmenu
1814
1815menu "Power management options"
1816
1817source "kernel/power/Kconfig"
1818
1819config ARCH_SUSPEND_POSSIBLE
1820	depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
1821		CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
1822	def_bool y
1823
1824config ARM_CPU_SUSPEND
1825	def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
1826	depends on ARCH_SUSPEND_POSSIBLE
1827
1828config ARCH_HIBERNATION_POSSIBLE
1829	bool
1830	depends on MMU
1831	default y if ARCH_SUSPEND_POSSIBLE
1832
1833endmenu
1834
1835source "arch/arm/Kconfig.assembler"
1836