xref: /openbmc/linux/arch/arm/Kconfig (revision 0526b56c)
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_NMI_SAFE_CMPXCHG if CPU_V7 || CPU_V7M || CPU_V6K
28	select ARCH_HAS_GCOV_PROFILE_ALL
29	select ARCH_KEEP_MEMBLOCK
30	select ARCH_HAS_UBSAN_SANITIZE_ALL
31	select ARCH_MIGHT_HAVE_PC_PARPORT
32	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
33	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
34	select ARCH_SUPPORTS_ATOMIC_RMW
35	select ARCH_SUPPORTS_HUGETLBFS if ARM_LPAE
36	select ARCH_USE_BUILTIN_BSWAP
37	select ARCH_USE_CMPXCHG_LOCKREF
38	select ARCH_USE_MEMTEST
39	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
40	select ARCH_WANT_GENERAL_HUGETLB
41	select ARCH_WANT_IPC_PARSE_VERSION
42	select ARCH_WANT_LD_ORPHAN_WARN
43	select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
44	select BUILDTIME_TABLE_SORT if MMU
45	select COMMON_CLK if !(ARCH_RPC || ARCH_FOOTBRIDGE)
46	select CLONE_BACKWARDS
47	select CPU_PM if SUSPEND || CPU_IDLE
48	select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
49	select DMA_DECLARE_COHERENT
50	select DMA_GLOBAL_POOL if !MMU
51	select DMA_OPS
52	select DMA_NONCOHERENT_MMAP if MMU
53	select EDAC_SUPPORT
54	select EDAC_ATOMIC_SCRUB
55	select GENERIC_ALLOCATOR
56	select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
57	select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
58	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
59	select GENERIC_IRQ_IPI if SMP
60	select GENERIC_CPU_AUTOPROBE
61	select GENERIC_EARLY_IOREMAP
62	select GENERIC_IDLE_POLL_SETUP
63	select GENERIC_IRQ_MULTI_HANDLER
64	select GENERIC_IRQ_PROBE
65	select GENERIC_IRQ_SHOW
66	select GENERIC_IRQ_SHOW_LEVEL
67	select GENERIC_LIB_DEVMEM_IS_ALLOWED
68	select GENERIC_PCI_IOMAP
69	select GENERIC_SCHED_CLOCK
70	select GENERIC_SMP_IDLE_THREAD
71	select HARDIRQS_SW_RESEND
72	select HAS_IOPORT
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 0xa0000000 if ARCH_PXA
286	default 0xc0000000 if ARCH_EP93XX || ARCH_SA1100
287	default 0
288	help
289	  Please provide the physical address corresponding to the
290	  location of main memory in your system.
291
292config GENERIC_BUG
293	def_bool y
294	depends on BUG
295
296config PGTABLE_LEVELS
297	int
298	default 3 if ARM_LPAE
299	default 2
300
301menu "System Type"
302
303config MMU
304	bool "MMU-based Paged Memory Management Support"
305	default y
306	help
307	  Select if you want MMU-based virtualised addressing space
308	  support by paged memory management. If unsure, say 'Y'.
309
310config ARM_SINGLE_ARMV7M
311	def_bool !MMU
312	select ARM_NVIC
313	select CPU_V7M
314	select NO_IOPORT_MAP
315
316config ARCH_MMAP_RND_BITS_MIN
317	default 8
318
319config ARCH_MMAP_RND_BITS_MAX
320	default 14 if PAGE_OFFSET=0x40000000
321	default 15 if PAGE_OFFSET=0x80000000
322	default 16
323
324config ARCH_MULTIPLATFORM
325	bool "Require kernel to be portable to multiple machines" if EXPERT
326	depends on MMU && !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
327	default y
328	help
329	  In general, all Arm machines can be supported in a single
330	  kernel image, covering either Armv4/v5 or Armv6/v7.
331
332	  However, some configuration options require hardcoding machine
333	  specific physical addresses or enable errata workarounds that may
334	  break other machines.
335
336	  Selecting N here allows using those options, including
337	  DEBUG_UNCOMPRESS, XIP_KERNEL and ZBOOT_ROM. If unsure, say Y.
338
339menu "Platform selection"
340	depends on MMU
341
342comment "CPU Core family selection"
343
344config ARCH_MULTI_V4
345	bool "ARMv4 based platforms (FA526, StrongARM)"
346	depends on !ARCH_MULTI_V6_V7
347	# https://github.com/llvm/llvm-project/issues/50764
348	depends on !LD_IS_LLD || LLD_VERSION >= 160000
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	# https://github.com/llvm/llvm-project/issues/50764
356	depends on !LD_IS_LLD || LLD_VERSION >= 160000
357	select ARCH_MULTI_V4_V5
358	select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
359		CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
360		CPU_ARM925T || CPU_ARM940T)
361
362config ARCH_MULTI_V5
363	bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
364	depends on !ARCH_MULTI_V6_V7
365	select ARCH_MULTI_V4_V5
366	select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
367		CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
368		CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
369
370config ARCH_MULTI_V4_V5
371	bool
372
373config ARCH_MULTI_V6
374	bool "ARMv6 based platforms (ARM11)"
375	select ARCH_MULTI_V6_V7
376	select CPU_V6K
377
378config ARCH_MULTI_V7
379	bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
380	default y
381	select ARCH_MULTI_V6_V7
382	select CPU_V7
383	select HAVE_SMP
384
385config ARCH_MULTI_V6_V7
386	bool
387	select MIGHT_HAVE_CACHE_L2X0
388
389config ARCH_MULTI_CPU_AUTO
390	def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
391	select ARCH_MULTI_V5
392
393endmenu
394
395config ARCH_VIRT
396	bool "Dummy Virtual Machine"
397	depends on ARCH_MULTI_V7
398	select ARM_AMBA
399	select ARM_GIC
400	select ARM_GIC_V2M if PCI
401	select ARM_GIC_V3
402	select ARM_GIC_V3_ITS if PCI
403	select ARM_PSCI
404	select HAVE_ARM_ARCH_TIMER
405
406config ARCH_AIROHA
407	bool "Airoha SoC Support"
408	depends on ARCH_MULTI_V7
409	select ARM_AMBA
410	select ARM_GIC
411	select ARM_GIC_V3
412	select ARM_PSCI
413	select HAVE_ARM_ARCH_TIMER
414	help
415	  Support for Airoha EN7523 SoCs
416
417#
418# This is sorted alphabetically by mach-* pathname.  However, plat-*
419# Kconfigs may be included either alphabetically (according to the
420# plat- suffix) or along side the corresponding mach-* source.
421#
422source "arch/arm/mach-actions/Kconfig"
423
424source "arch/arm/mach-alpine/Kconfig"
425
426source "arch/arm/mach-artpec/Kconfig"
427
428source "arch/arm/mach-asm9260/Kconfig"
429
430source "arch/arm/mach-aspeed/Kconfig"
431
432source "arch/arm/mach-at91/Kconfig"
433
434source "arch/arm/mach-axxia/Kconfig"
435
436source "arch/arm/mach-bcm/Kconfig"
437
438source "arch/arm/mach-berlin/Kconfig"
439
440source "arch/arm/mach-clps711x/Kconfig"
441
442source "arch/arm/mach-davinci/Kconfig"
443
444source "arch/arm/mach-digicolor/Kconfig"
445
446source "arch/arm/mach-dove/Kconfig"
447
448source "arch/arm/mach-ep93xx/Kconfig"
449
450source "arch/arm/mach-exynos/Kconfig"
451
452source "arch/arm/mach-footbridge/Kconfig"
453
454source "arch/arm/mach-gemini/Kconfig"
455
456source "arch/arm/mach-highbank/Kconfig"
457
458source "arch/arm/mach-hisi/Kconfig"
459
460source "arch/arm/mach-hpe/Kconfig"
461
462source "arch/arm/mach-imx/Kconfig"
463
464source "arch/arm/mach-ixp4xx/Kconfig"
465
466source "arch/arm/mach-keystone/Kconfig"
467
468source "arch/arm/mach-lpc32xx/Kconfig"
469
470source "arch/arm/mach-mediatek/Kconfig"
471
472source "arch/arm/mach-meson/Kconfig"
473
474source "arch/arm/mach-milbeaut/Kconfig"
475
476source "arch/arm/mach-mmp/Kconfig"
477
478source "arch/arm/mach-moxart/Kconfig"
479
480source "arch/arm/mach-mstar/Kconfig"
481
482source "arch/arm/mach-mv78xx0/Kconfig"
483
484source "arch/arm/mach-mvebu/Kconfig"
485
486source "arch/arm/mach-mxs/Kconfig"
487
488source "arch/arm/mach-nomadik/Kconfig"
489
490source "arch/arm/mach-npcm/Kconfig"
491
492source "arch/arm/mach-nspire/Kconfig"
493
494source "arch/arm/mach-omap1/Kconfig"
495
496source "arch/arm/mach-omap2/Kconfig"
497
498source "arch/arm/mach-orion5x/Kconfig"
499
500source "arch/arm/mach-pxa/Kconfig"
501
502source "arch/arm/mach-qcom/Kconfig"
503
504source "arch/arm/mach-rda/Kconfig"
505
506source "arch/arm/mach-realtek/Kconfig"
507
508source "arch/arm/mach-rpc/Kconfig"
509
510source "arch/arm/mach-rockchip/Kconfig"
511
512source "arch/arm/mach-s3c/Kconfig"
513
514source "arch/arm/mach-s5pv210/Kconfig"
515
516source "arch/arm/mach-sa1100/Kconfig"
517
518source "arch/arm/mach-shmobile/Kconfig"
519
520source "arch/arm/mach-socfpga/Kconfig"
521
522source "arch/arm/mach-spear/Kconfig"
523
524source "arch/arm/mach-sti/Kconfig"
525
526source "arch/arm/mach-stm32/Kconfig"
527
528source "arch/arm/mach-sunplus/Kconfig"
529
530source "arch/arm/mach-sunxi/Kconfig"
531
532source "arch/arm/mach-tegra/Kconfig"
533
534source "arch/arm/mach-uniphier/Kconfig"
535
536source "arch/arm/mach-ux500/Kconfig"
537
538source "arch/arm/mach-versatile/Kconfig"
539
540source "arch/arm/mach-vt8500/Kconfig"
541
542source "arch/arm/mach-zynq/Kconfig"
543
544# ARMv7-M architecture
545config ARCH_LPC18XX
546	bool "NXP LPC18xx/LPC43xx"
547	depends on ARM_SINGLE_ARMV7M
548	select ARCH_HAS_RESET_CONTROLLER
549	select ARM_AMBA
550	select CLKSRC_LPC32XX
551	select PINCTRL
552	help
553	  Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
554	  high performance microcontrollers.
555
556config ARCH_MPS2
557	bool "ARM MPS2 platform"
558	depends on ARM_SINGLE_ARMV7M
559	select ARM_AMBA
560	select CLKSRC_MPS2
561	help
562	  Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
563	  with a range of available cores like Cortex-M3/M4/M7.
564
565	  Please, note that depends which Application Note is used memory map
566	  for the platform may vary, so adjustment of RAM base might be needed.
567
568# Definitions to make life easier
569config ARCH_ACORN
570	bool
571
572config PLAT_ORION
573	bool
574	select CLKSRC_MMIO
575	select GENERIC_IRQ_CHIP
576	select IRQ_DOMAIN
577
578config PLAT_ORION_LEGACY
579	bool
580	select PLAT_ORION
581
582config PLAT_VERSATILE
583	bool
584
585source "arch/arm/mm/Kconfig"
586
587config IWMMXT
588	bool "Enable iWMMXt support"
589	depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
590	default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
591	help
592	  Enable support for iWMMXt context switching at run time if
593	  running on a CPU that supports it.
594
595if !MMU
596source "arch/arm/Kconfig-nommu"
597endif
598
599config PJ4B_ERRATA_4742
600	bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
601	depends on CPU_PJ4B && MACH_ARMADA_370
602	default y
603	help
604	  When coming out of either a Wait for Interrupt (WFI) or a Wait for
605	  Event (WFE) IDLE states, a specific timing sensitivity exists between
606	  the retiring WFI/WFE instructions and the newly issued subsequent
607	  instructions.  This sensitivity can result in a CPU hang scenario.
608	  Workaround:
609	  The software must insert either a Data Synchronization Barrier (DSB)
610	  or Data Memory Barrier (DMB) command immediately after the WFI/WFE
611	  instruction
612
613config ARM_ERRATA_326103
614	bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
615	depends on CPU_V6
616	help
617	  Executing a SWP instruction to read-only memory does not set bit 11
618	  of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
619	  treat the access as a read, preventing a COW from occurring and
620	  causing the faulting task to livelock.
621
622config ARM_ERRATA_411920
623	bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
624	depends on CPU_V6 || CPU_V6K
625	help
626	  Invalidation of the Instruction Cache operation can
627	  fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
628	  It does not affect the MPCore. This option enables the ARM Ltd.
629	  recommended workaround.
630
631config ARM_ERRATA_430973
632	bool "ARM errata: Stale prediction on replaced interworking branch"
633	depends on CPU_V7
634	help
635	  This option enables the workaround for the 430973 Cortex-A8
636	  r1p* erratum. If a code sequence containing an ARM/Thumb
637	  interworking branch is replaced with another code sequence at the
638	  same virtual address, whether due to self-modifying code or virtual
639	  to physical address re-mapping, Cortex-A8 does not recover from the
640	  stale interworking branch prediction. This results in Cortex-A8
641	  executing the new code sequence in the incorrect ARM or Thumb state.
642	  The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
643	  and also flushes the branch target cache at every context switch.
644	  Note that setting specific bits in the ACTLR register may not be
645	  available in non-secure mode.
646
647config ARM_ERRATA_458693
648	bool "ARM errata: Processor deadlock when a false hazard is created"
649	depends on CPU_V7
650	depends on !ARCH_MULTIPLATFORM
651	help
652	  This option enables the workaround for the 458693 Cortex-A8 (r2p0)
653	  erratum. For very specific sequences of memory operations, it is
654	  possible for a hazard condition intended for a cache line to instead
655	  be incorrectly associated with a different cache line. This false
656	  hazard might then cause a processor deadlock. The workaround enables
657	  the L1 caching of the NEON accesses and disables the PLD instruction
658	  in the ACTLR register. Note that setting specific bits in the ACTLR
659	  register may not be available in non-secure mode and thus is not
660	  available on a multiplatform kernel. This should be applied by the
661	  bootloader instead.
662
663config ARM_ERRATA_460075
664	bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
665	depends on CPU_V7
666	depends on !ARCH_MULTIPLATFORM
667	help
668	  This option enables the workaround for the 460075 Cortex-A8 (r2p0)
669	  erratum. Any asynchronous access to the L2 cache may encounter a
670	  situation in which recent store transactions to the L2 cache are lost
671	  and overwritten with stale memory contents from external memory. The
672	  workaround disables the write-allocate mode for the L2 cache via the
673	  ACTLR register. Note that setting specific bits in the ACTLR register
674	  may not be available in non-secure mode and thus is not available on
675	  a multiplatform kernel. This should be applied by the bootloader
676	  instead.
677
678config ARM_ERRATA_742230
679	bool "ARM errata: DMB operation may be faulty"
680	depends on CPU_V7 && SMP
681	depends on !ARCH_MULTIPLATFORM
682	help
683	  This option enables the workaround for the 742230 Cortex-A9
684	  (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
685	  between two write operations may not ensure the correct visibility
686	  ordering of the two writes. This workaround sets a specific bit in
687	  the diagnostic register of the Cortex-A9 which causes the DMB
688	  instruction to behave as a DSB, ensuring the correct behaviour of
689	  the two writes. Note that setting specific bits in the diagnostics
690	  register may not be available in non-secure mode and thus is not
691	  available on a multiplatform kernel. This should be applied by the
692	  bootloader instead.
693
694config ARM_ERRATA_742231
695	bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
696	depends on CPU_V7 && SMP
697	depends on !ARCH_MULTIPLATFORM
698	help
699	  This option enables the workaround for the 742231 Cortex-A9
700	  (r2p0..r2p2) erratum. Under certain conditions, specific to the
701	  Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
702	  accessing some data located in the same cache line, may get corrupted
703	  data due to bad handling of the address hazard when the line gets
704	  replaced from one of the CPUs at the same time as another CPU is
705	  accessing it. This workaround sets specific bits in the diagnostic
706	  register of the Cortex-A9 which reduces the linefill issuing
707	  capabilities of the processor. Note that setting specific bits in the
708	  diagnostics register may not be available in non-secure mode and thus
709	  is not available on a multiplatform kernel. This should be applied by
710	  the bootloader instead.
711
712config ARM_ERRATA_643719
713	bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
714	depends on CPU_V7 && SMP
715	default y
716	help
717	  This option enables the workaround for the 643719 Cortex-A9 (prior to
718	  r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
719	  register returns zero when it should return one. The workaround
720	  corrects this value, ensuring cache maintenance operations which use
721	  it behave as intended and avoiding data corruption.
722
723config ARM_ERRATA_720789
724	bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
725	depends on CPU_V7
726	help
727	  This option enables the workaround for the 720789 Cortex-A9 (prior to
728	  r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
729	  broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
730	  As a consequence of this erratum, some TLB entries which should be
731	  invalidated are not, resulting in an incoherency in the system page
732	  tables. The workaround changes the TLB flushing routines to invalidate
733	  entries regardless of the ASID.
734
735config ARM_ERRATA_743622
736	bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
737	depends on CPU_V7
738	depends on !ARCH_MULTIPLATFORM
739	help
740	  This option enables the workaround for the 743622 Cortex-A9
741	  (r2p*) erratum. Under very rare conditions, a faulty
742	  optimisation in the Cortex-A9 Store Buffer may lead to data
743	  corruption. This workaround sets a specific bit in the diagnostic
744	  register of the Cortex-A9 which disables the Store Buffer
745	  optimisation, preventing the defect from occurring. This has no
746	  visible impact on the overall performance or power consumption of the
747	  processor. Note that setting specific bits in the diagnostics register
748	  may not be available in non-secure mode and thus is not available on a
749	  multiplatform kernel. This should be applied by the bootloader instead.
750
751config ARM_ERRATA_751472
752	bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
753	depends on CPU_V7
754	depends on !ARCH_MULTIPLATFORM
755	help
756	  This option enables the workaround for the 751472 Cortex-A9 (prior
757	  to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
758	  completion of a following broadcasted operation if the second
759	  operation is received by a CPU before the ICIALLUIS has completed,
760	  potentially leading to corrupted entries in the cache or TLB.
761	  Note that setting specific bits in the diagnostics register may
762	  not be available in non-secure mode and thus is not available on
763	  a multiplatform kernel. This should be applied by the bootloader
764	  instead.
765
766config ARM_ERRATA_754322
767	bool "ARM errata: possible faulty MMU translations following an ASID switch"
768	depends on CPU_V7
769	help
770	  This option enables the workaround for the 754322 Cortex-A9 (r2p*,
771	  r3p*) erratum. A speculative memory access may cause a page table walk
772	  which starts prior to an ASID switch but completes afterwards. This
773	  can populate the micro-TLB with a stale entry which may be hit with
774	  the new ASID. This workaround places two dsb instructions in the mm
775	  switching code so that no page table walks can cross the ASID switch.
776
777config ARM_ERRATA_754327
778	bool "ARM errata: no automatic Store Buffer drain"
779	depends on CPU_V7 && SMP
780	help
781	  This option enables the workaround for the 754327 Cortex-A9 (prior to
782	  r2p0) erratum. The Store Buffer does not have any automatic draining
783	  mechanism and therefore a livelock may occur if an external agent
784	  continuously polls a memory location waiting to observe an update.
785	  This workaround defines cpu_relax() as smp_mb(), preventing correctly
786	  written polling loops from denying visibility of updates to memory.
787
788config ARM_ERRATA_364296
789	bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
790	depends on CPU_V6
791	help
792	  This options enables the workaround for the 364296 ARM1136
793	  r0p2 erratum (possible cache data corruption with
794	  hit-under-miss enabled). It sets the undocumented bit 31 in
795	  the auxiliary control register and the FI bit in the control
796	  register, thus disabling hit-under-miss without putting the
797	  processor into full low interrupt latency mode. ARM11MPCore
798	  is not affected.
799
800config ARM_ERRATA_764369
801	bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
802	depends on CPU_V7 && SMP
803	help
804	  This option enables the workaround for erratum 764369
805	  affecting Cortex-A9 MPCore with two or more processors (all
806	  current revisions). Under certain timing circumstances, a data
807	  cache line maintenance operation by MVA targeting an Inner
808	  Shareable memory region may fail to proceed up to either the
809	  Point of Coherency or to the Point of Unification of the
810	  system. This workaround adds a DSB instruction before the
811	  relevant cache maintenance functions and sets a specific bit
812	  in the diagnostic control register of the SCU.
813
814config ARM_ERRATA_764319
815	bool "ARM errata: Read to DBGPRSR and DBGOSLSR may generate Undefined instruction"
816	depends on CPU_V7
817	help
818	  This option enables the workaround for the 764319 Cortex A-9 erratum.
819	  CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
820	  unexpected Undefined Instruction exception when the DBGSWENABLE
821	  external pin is set to 0, even when the CP14 accesses are performed
822	  from a privileged mode. This work around catches the exception in a
823	  way the kernel does not stop execution.
824
825config ARM_ERRATA_775420
826       bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
827       depends on CPU_V7
828       help
829	 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
830	 r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
831	 operation aborts with MMU exception, it might cause the processor
832	 to deadlock. This workaround puts DSB before executing ISB if
833	 an abort may occur on cache maintenance.
834
835config ARM_ERRATA_798181
836	bool "ARM errata: TLBI/DSB failure on Cortex-A15"
837	depends on CPU_V7 && SMP
838	help
839	  On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
840	  adequately shooting down all use of the old entries. This
841	  option enables the Linux kernel workaround for this erratum
842	  which sends an IPI to the CPUs that are running the same ASID
843	  as the one being invalidated.
844
845config ARM_ERRATA_773022
846	bool "ARM errata: incorrect instructions may be executed from loop buffer"
847	depends on CPU_V7
848	help
849	  This option enables the workaround for the 773022 Cortex-A15
850	  (up to r0p4) erratum. In certain rare sequences of code, the
851	  loop buffer may deliver incorrect instructions. This
852	  workaround disables the loop buffer to avoid the erratum.
853
854config ARM_ERRATA_818325_852422
855	bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
856	depends on CPU_V7
857	help
858	  This option enables the workaround for:
859	  - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
860	    instruction might deadlock.  Fixed in r0p1.
861	  - Cortex-A12 852422: Execution of a sequence of instructions might
862	    lead to either a data corruption or a CPU deadlock.  Not fixed in
863	    any Cortex-A12 cores yet.
864	  This workaround for all both errata involves setting bit[12] of the
865	  Feature Register. This bit disables an optimisation applied to a
866	  sequence of 2 instructions that use opposing condition codes.
867
868config ARM_ERRATA_821420
869	bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
870	depends on CPU_V7
871	help
872	  This option enables the workaround for the 821420 Cortex-A12
873	  (all revs) erratum. In very rare timing conditions, a sequence
874	  of VMOV to Core registers instructions, for which the second
875	  one is in the shadow of a branch or abort, can lead to a
876	  deadlock when the VMOV instructions are issued out-of-order.
877
878config ARM_ERRATA_825619
879	bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
880	depends on CPU_V7
881	help
882	  This option enables the workaround for the 825619 Cortex-A12
883	  (all revs) erratum. Within rare timing constraints, executing a
884	  DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
885	  and Device/Strongly-Ordered loads and stores might cause deadlock
886
887config ARM_ERRATA_857271
888	bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
889	depends on CPU_V7
890	help
891	  This option enables the workaround for the 857271 Cortex-A12
892	  (all revs) erratum. Under very rare timing conditions, the CPU might
893	  hang. The workaround is expected to have a < 1% performance impact.
894
895config ARM_ERRATA_852421
896	bool "ARM errata: A17: DMB ST might fail to create order between stores"
897	depends on CPU_V7
898	help
899	  This option enables the workaround for the 852421 Cortex-A17
900	  (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
901	  execution of a DMB ST instruction might fail to properly order
902	  stores from GroupA and stores from GroupB.
903
904config ARM_ERRATA_852423
905	bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
906	depends on CPU_V7
907	help
908	  This option enables the workaround for:
909	  - Cortex-A17 852423: Execution of a sequence of instructions might
910	    lead to either a data corruption or a CPU deadlock.  Not fixed in
911	    any Cortex-A17 cores yet.
912	  This is identical to Cortex-A12 erratum 852422.  It is a separate
913	  config option from the A12 erratum due to the way errata are checked
914	  for and handled.
915
916config ARM_ERRATA_857272
917	bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
918	depends on CPU_V7
919	help
920	  This option enables the workaround for the 857272 Cortex-A17 erratum.
921	  This erratum is not known to be fixed in any A17 revision.
922	  This is identical to Cortex-A12 erratum 857271.  It is a separate
923	  config option from the A12 erratum due to the way errata are checked
924	  for and handled.
925
926endmenu
927
928source "arch/arm/common/Kconfig"
929
930menu "Bus support"
931
932config ISA
933	bool
934	help
935	  Find out whether you have ISA slots on your motherboard.  ISA is the
936	  name of a bus system, i.e. the way the CPU talks to the other stuff
937	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
938	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
939	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
940
941# Select ISA DMA interface
942config ISA_DMA_API
943	bool
944
945config ARM_ERRATA_814220
946	bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
947	depends on CPU_V7
948	help
949	  The v7 ARM states that all cache and branch predictor maintenance
950	  operations that do not specify an address execute, relative to
951	  each other, in program order.
952	  However, because of this erratum, an L2 set/way cache maintenance
953	  operation can overtake an L1 set/way cache maintenance operation.
954	  This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
955	  r0p4, r0p5.
956
957endmenu
958
959menu "Kernel Features"
960
961config HAVE_SMP
962	bool
963	help
964	  This option should be selected by machines which have an SMP-
965	  capable CPU.
966
967	  The only effect of this option is to make the SMP-related
968	  options available to the user for configuration.
969
970config SMP
971	bool "Symmetric Multi-Processing"
972	depends on CPU_V6K || CPU_V7
973	depends on HAVE_SMP
974	depends on MMU || ARM_MPU
975	select IRQ_WORK
976	help
977	  This enables support for systems with more than one CPU. If you have
978	  a system with only one CPU, say N. If you have a system with more
979	  than one CPU, say Y.
980
981	  If you say N here, the kernel will run on uni- and multiprocessor
982	  machines, but will use only one CPU of a multiprocessor machine. If
983	  you say Y here, the kernel will run on many, but not all,
984	  uniprocessor machines. On a uniprocessor machine, the kernel
985	  will run faster if you say N here.
986
987	  See also <file:Documentation/arch/x86/i386/IO-APIC.rst>,
988	  <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
989	  <http://tldp.org/HOWTO/SMP-HOWTO.html>.
990
991	  If you don't know what to do here, say N.
992
993config SMP_ON_UP
994	bool "Allow booting SMP kernel on uniprocessor systems"
995	depends on SMP && MMU
996	default y
997	help
998	  SMP kernels contain instructions which fail on non-SMP processors.
999	  Enabling this option allows the kernel to modify itself to make
1000	  these instructions safe.  Disabling it allows about 1K of space
1001	  savings.
1002
1003	  If you don't know what to do here, say Y.
1004
1005
1006config CURRENT_POINTER_IN_TPIDRURO
1007	def_bool y
1008	depends on CPU_32v6K && !CPU_V6
1009
1010config IRQSTACKS
1011	def_bool y
1012	select HAVE_IRQ_EXIT_ON_IRQ_STACK
1013	select HAVE_SOFTIRQ_ON_OWN_STACK
1014
1015config ARM_CPU_TOPOLOGY
1016	bool "Support cpu topology definition"
1017	depends on SMP && CPU_V7
1018	default y
1019	help
1020	  Support ARM cpu topology definition. The MPIDR register defines
1021	  affinity between processors which is then used to describe the cpu
1022	  topology of an ARM System.
1023
1024config SCHED_MC
1025	bool "Multi-core scheduler support"
1026	depends on ARM_CPU_TOPOLOGY
1027	help
1028	  Multi-core scheduler support improves the CPU scheduler's decision
1029	  making when dealing with multi-core CPU chips at a cost of slightly
1030	  increased overhead in some places. If unsure say N here.
1031
1032config SCHED_SMT
1033	bool "SMT scheduler support"
1034	depends on ARM_CPU_TOPOLOGY
1035	help
1036	  Improves the CPU scheduler's decision making when dealing with
1037	  MultiThreading at a cost of slightly increased overhead in some
1038	  places. If unsure say N here.
1039
1040config HAVE_ARM_SCU
1041	bool
1042	help
1043	  This option enables support for the ARM snoop control unit
1044
1045config HAVE_ARM_ARCH_TIMER
1046	bool "Architected timer support"
1047	depends on CPU_V7
1048	select ARM_ARCH_TIMER
1049	help
1050	  This option enables support for the ARM architected timer
1051
1052config HAVE_ARM_TWD
1053	bool
1054	help
1055	  This options enables support for the ARM timer and watchdog unit
1056
1057config MCPM
1058	bool "Multi-Cluster Power Management"
1059	depends on CPU_V7 && SMP
1060	help
1061	  This option provides the common power management infrastructure
1062	  for (multi-)cluster based systems, such as big.LITTLE based
1063	  systems.
1064
1065config MCPM_QUAD_CLUSTER
1066	bool
1067	depends on MCPM
1068	help
1069	  To avoid wasting resources unnecessarily, MCPM only supports up
1070	  to 2 clusters by default.
1071	  Platforms with 3 or 4 clusters that use MCPM must select this
1072	  option to allow the additional clusters to be managed.
1073
1074config BIG_LITTLE
1075	bool "big.LITTLE support (Experimental)"
1076	depends on CPU_V7 && SMP
1077	select MCPM
1078	help
1079	  This option enables support selections for the big.LITTLE
1080	  system architecture.
1081
1082config BL_SWITCHER
1083	bool "big.LITTLE switcher support"
1084	depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
1085	select CPU_PM
1086	help
1087	  The big.LITTLE "switcher" provides the core functionality to
1088	  transparently handle transition between a cluster of A15's
1089	  and a cluster of A7's in a big.LITTLE system.
1090
1091config BL_SWITCHER_DUMMY_IF
1092	tristate "Simple big.LITTLE switcher user interface"
1093	depends on BL_SWITCHER && DEBUG_KERNEL
1094	help
1095	  This is a simple and dummy char dev interface to control
1096	  the big.LITTLE switcher core code.  It is meant for
1097	  debugging purposes only.
1098
1099choice
1100	prompt "Memory split"
1101	depends on MMU
1102	default VMSPLIT_3G
1103	help
1104	  Select the desired split between kernel and user memory.
1105
1106	  If you are not absolutely sure what you are doing, leave this
1107	  option alone!
1108
1109	config VMSPLIT_3G
1110		bool "3G/1G user/kernel split"
1111	config VMSPLIT_3G_OPT
1112		depends on !ARM_LPAE
1113		bool "3G/1G user/kernel split (for full 1G low memory)"
1114	config VMSPLIT_2G
1115		bool "2G/2G user/kernel split"
1116	config VMSPLIT_1G
1117		bool "1G/3G user/kernel split"
1118endchoice
1119
1120config PAGE_OFFSET
1121	hex
1122	default PHYS_OFFSET if !MMU
1123	default 0x40000000 if VMSPLIT_1G
1124	default 0x80000000 if VMSPLIT_2G
1125	default 0xB0000000 if VMSPLIT_3G_OPT
1126	default 0xC0000000
1127
1128config KASAN_SHADOW_OFFSET
1129	hex
1130	depends on KASAN
1131	default 0x1f000000 if PAGE_OFFSET=0x40000000
1132	default 0x5f000000 if PAGE_OFFSET=0x80000000
1133	default 0x9f000000 if PAGE_OFFSET=0xC0000000
1134	default 0x8f000000 if PAGE_OFFSET=0xB0000000
1135	default 0xffffffff
1136
1137config NR_CPUS
1138	int "Maximum number of CPUs (2-32)"
1139	range 2 16 if DEBUG_KMAP_LOCAL
1140	range 2 32 if !DEBUG_KMAP_LOCAL
1141	depends on SMP
1142	default "4"
1143	help
1144	  The maximum number of CPUs that the kernel can support.
1145	  Up to 32 CPUs can be supported, or up to 16 if kmap_local()
1146	  debugging is enabled, which uses half of the per-CPU fixmap
1147	  slots as guard regions.
1148
1149config HOTPLUG_CPU
1150	bool "Support for hot-pluggable CPUs"
1151	depends on SMP
1152	select GENERIC_IRQ_MIGRATION
1153	help
1154	  Say Y here to experiment with turning CPUs off and on.  CPUs
1155	  can be controlled through /sys/devices/system/cpu.
1156
1157config ARM_PSCI
1158	bool "Support for the ARM Power State Coordination Interface (PSCI)"
1159	depends on HAVE_ARM_SMCCC
1160	select ARM_PSCI_FW
1161	help
1162	  Say Y here if you want Linux to communicate with system firmware
1163	  implementing the PSCI specification for CPU-centric power
1164	  management operations described in ARM document number ARM DEN
1165	  0022A ("Power State Coordination Interface System Software on
1166	  ARM processors").
1167
1168config HZ_FIXED
1169	int
1170	default 128 if SOC_AT91RM9200
1171	default 0
1172
1173choice
1174	depends on HZ_FIXED = 0
1175	prompt "Timer frequency"
1176
1177config HZ_100
1178	bool "100 Hz"
1179
1180config HZ_200
1181	bool "200 Hz"
1182
1183config HZ_250
1184	bool "250 Hz"
1185
1186config HZ_300
1187	bool "300 Hz"
1188
1189config HZ_500
1190	bool "500 Hz"
1191
1192config HZ_1000
1193	bool "1000 Hz"
1194
1195endchoice
1196
1197config HZ
1198	int
1199	default HZ_FIXED if HZ_FIXED != 0
1200	default 100 if HZ_100
1201	default 200 if HZ_200
1202	default 250 if HZ_250
1203	default 300 if HZ_300
1204	default 500 if HZ_500
1205	default 1000
1206
1207config SCHED_HRTICK
1208	def_bool HIGH_RES_TIMERS
1209
1210config THUMB2_KERNEL
1211	bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1212	depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1213	default y if CPU_THUMBONLY
1214	select ARM_UNWIND
1215	help
1216	  By enabling this option, the kernel will be compiled in
1217	  Thumb-2 mode.
1218
1219	  If unsure, say N.
1220
1221config ARM_PATCH_IDIV
1222	bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
1223	depends on CPU_32v7
1224	default y
1225	help
1226	  The ARM compiler inserts calls to __aeabi_idiv() and
1227	  __aeabi_uidiv() when it needs to perform division on signed
1228	  and unsigned integers. Some v7 CPUs have support for the sdiv
1229	  and udiv instructions that can be used to implement those
1230	  functions.
1231
1232	  Enabling this option allows the kernel to modify itself to
1233	  replace the first two instructions of these library functions
1234	  with the sdiv or udiv plus "bx lr" instructions when the CPU
1235	  it is running on supports them. Typically this will be faster
1236	  and less power intensive than running the original library
1237	  code to do integer division.
1238
1239config AEABI
1240	bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1241		!CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1242	default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
1243	help
1244	  This option allows for the kernel to be compiled using the latest
1245	  ARM ABI (aka EABI).  This is only useful if you are using a user
1246	  space environment that is also compiled with EABI.
1247
1248	  Since there are major incompatibilities between the legacy ABI and
1249	  EABI, especially with regard to structure member alignment, this
1250	  option also changes the kernel syscall calling convention to
1251	  disambiguate both ABIs and allow for backward compatibility support
1252	  (selected with CONFIG_OABI_COMPAT).
1253
1254	  To use this you need GCC version 4.0.0 or later.
1255
1256config OABI_COMPAT
1257	bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1258	depends on AEABI && !THUMB2_KERNEL
1259	help
1260	  This option preserves the old syscall interface along with the
1261	  new (ARM EABI) one. It also provides a compatibility layer to
1262	  intercept syscalls that have structure arguments which layout
1263	  in memory differs between the legacy ABI and the new ARM EABI
1264	  (only for non "thumb" binaries). This option adds a tiny
1265	  overhead to all syscalls and produces a slightly larger kernel.
1266
1267	  The seccomp filter system will not be available when this is
1268	  selected, since there is no way yet to sensibly distinguish
1269	  between calling conventions during filtering.
1270
1271	  If you know you'll be using only pure EABI user space then you
1272	  can say N here. If this option is not selected and you attempt
1273	  to execute a legacy ABI binary then the result will be
1274	  UNPREDICTABLE (in fact it can be predicted that it won't work
1275	  at all). If in doubt say N.
1276
1277config ARCH_SELECT_MEMORY_MODEL
1278	def_bool y
1279
1280config ARCH_FLATMEM_ENABLE
1281	def_bool !(ARCH_RPC || ARCH_SA1100)
1282
1283config ARCH_SPARSEMEM_ENABLE
1284	def_bool !ARCH_FOOTBRIDGE
1285	select SPARSEMEM_STATIC if SPARSEMEM
1286
1287config HIGHMEM
1288	bool "High Memory Support"
1289	depends on MMU
1290	select KMAP_LOCAL
1291	select KMAP_LOCAL_NON_LINEAR_PTE_ARRAY
1292	help
1293	  The address space of ARM processors is only 4 Gigabytes large
1294	  and it has to accommodate user address space, kernel address
1295	  space as well as some memory mapped IO. That means that, if you
1296	  have a large amount of physical memory and/or IO, not all of the
1297	  memory can be "permanently mapped" by the kernel. The physical
1298	  memory that is not permanently mapped is called "high memory".
1299
1300	  Depending on the selected kernel/user memory split, minimum
1301	  vmalloc space and actual amount of RAM, you may not need this
1302	  option which should result in a slightly faster kernel.
1303
1304	  If unsure, say n.
1305
1306config HIGHPTE
1307	bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1308	depends on HIGHMEM
1309	default y
1310	help
1311	  The VM uses one page of physical memory for each page table.
1312	  For systems with a lot of processes, this can use a lot of
1313	  precious low memory, eventually leading to low memory being
1314	  consumed by page tables.  Setting this option will allow
1315	  user-space 2nd level page tables to reside in high memory.
1316
1317config CPU_SW_DOMAIN_PAN
1318	bool "Enable use of CPU domains to implement privileged no-access"
1319	depends on MMU && !ARM_LPAE
1320	default y
1321	help
1322	  Increase kernel security by ensuring that normal kernel accesses
1323	  are unable to access userspace addresses.  This can help prevent
1324	  use-after-free bugs becoming an exploitable privilege escalation
1325	  by ensuring that magic values (such as LIST_POISON) will always
1326	  fault when dereferenced.
1327
1328	  CPUs with low-vector mappings use a best-efforts implementation.
1329	  Their lower 1MB needs to remain accessible for the vectors, but
1330	  the remainder of userspace will become appropriately inaccessible.
1331
1332config HW_PERF_EVENTS
1333	def_bool y
1334	depends on ARM_PMU
1335
1336config ARM_MODULE_PLTS
1337	bool "Use PLTs to allow module memory to spill over into vmalloc area"
1338	depends on MODULES
1339	select KASAN_VMALLOC if KASAN
1340	default y
1341	help
1342	  Allocate PLTs when loading modules so that jumps and calls whose
1343	  targets are too far away for their relative offsets to be encoded
1344	  in the instructions themselves can be bounced via veneers in the
1345	  module's PLT. This allows modules to be allocated in the generic
1346	  vmalloc area after the dedicated module memory area has been
1347	  exhausted. The modules will use slightly more memory, but after
1348	  rounding up to page size, the actual memory footprint is usually
1349	  the same.
1350
1351	  Disabling this is usually safe for small single-platform
1352	  configurations. If unsure, say y.
1353
1354config ARCH_FORCE_MAX_ORDER
1355	int "Order of maximal physically contiguous allocations"
1356	default "11" if SOC_AM33XX
1357	default "8" if SA1111
1358	default "10"
1359	help
1360	  The kernel page allocator limits the size of maximal physically
1361	  contiguous allocations. The limit is called MAX_ORDER and it
1362	  defines the maximal power of two of number of pages that can be
1363	  allocated as a single contiguous block. This option allows
1364	  overriding the default setting when ability to allocate very
1365	  large blocks of physically contiguous memory is required.
1366
1367	  Don't change if unsure.
1368
1369config ALIGNMENT_TRAP
1370	def_bool CPU_CP15_MMU
1371	select HAVE_PROC_CPU if PROC_FS
1372	help
1373	  ARM processors cannot fetch/store information which is not
1374	  naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1375	  address divisible by 4. On 32-bit ARM processors, these non-aligned
1376	  fetch/store instructions will be emulated in software if you say
1377	  here, which has a severe performance impact. This is necessary for
1378	  correct operation of some network protocols. With an IP-only
1379	  configuration it is safe to say N, otherwise say Y.
1380
1381config UACCESS_WITH_MEMCPY
1382	bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1383	depends on MMU
1384	default y if CPU_FEROCEON
1385	help
1386	  Implement faster copy_to_user and clear_user methods for CPU
1387	  cores where a 8-word STM instruction give significantly higher
1388	  memory write throughput than a sequence of individual 32bit stores.
1389
1390	  A possible side effect is a slight increase in scheduling latency
1391	  between threads sharing the same address space if they invoke
1392	  such copy operations with large buffers.
1393
1394	  However, if the CPU data cache is using a write-allocate mode,
1395	  this option is unlikely to provide any performance gain.
1396
1397config PARAVIRT
1398	bool "Enable paravirtualization code"
1399	help
1400	  This changes the kernel so it can modify itself when it is run
1401	  under a hypervisor, potentially improving performance significantly
1402	  over full virtualization.
1403
1404config PARAVIRT_TIME_ACCOUNTING
1405	bool "Paravirtual steal time accounting"
1406	select PARAVIRT
1407	help
1408	  Select this option to enable fine granularity task steal time
1409	  accounting. Time spent executing other tasks in parallel with
1410	  the current vCPU is discounted from the vCPU power. To account for
1411	  that, there can be a small performance impact.
1412
1413	  If in doubt, say N here.
1414
1415config XEN_DOM0
1416	def_bool y
1417	depends on XEN
1418
1419config XEN
1420	bool "Xen guest support on ARM"
1421	depends on ARM && AEABI && OF
1422	depends on CPU_V7 && !CPU_V6
1423	depends on !GENERIC_ATOMIC64
1424	depends on MMU
1425	select ARCH_DMA_ADDR_T_64BIT
1426	select ARM_PSCI
1427	select SWIOTLB
1428	select SWIOTLB_XEN
1429	select PARAVIRT
1430	help
1431	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1432
1433config CC_HAVE_STACKPROTECTOR_TLS
1434	def_bool $(cc-option,-mtp=cp15 -mstack-protector-guard=tls -mstack-protector-guard-offset=0)
1435
1436config STACKPROTECTOR_PER_TASK
1437	bool "Use a unique stack canary value for each task"
1438	depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA
1439	depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS
1440	select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS
1441	default y
1442	help
1443	  Due to the fact that GCC uses an ordinary symbol reference from
1444	  which to load the value of the stack canary, this value can only
1445	  change at reboot time on SMP systems, and all tasks running in the
1446	  kernel's address space are forced to use the same canary value for
1447	  the entire duration that the system is up.
1448
1449	  Enable this option to switch to a different method that uses a
1450	  different canary value for each task.
1451
1452endmenu
1453
1454menu "Boot options"
1455
1456config USE_OF
1457	bool "Flattened Device Tree support"
1458	select IRQ_DOMAIN
1459	select OF
1460	help
1461	  Include support for flattened device tree machine descriptions.
1462
1463config ATAGS
1464	bool "Support for the traditional ATAGS boot data passing"
1465	default y
1466	help
1467	  This is the traditional way of passing data to the kernel at boot
1468	  time. If you are solely relying on the flattened device tree (or
1469	  the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1470	  to remove ATAGS support from your kernel binary.
1471
1472config DEPRECATED_PARAM_STRUCT
1473	bool "Provide old way to pass kernel parameters"
1474	depends on ATAGS
1475	help
1476	  This was deprecated in 2001 and announced to live on for 5 years.
1477	  Some old boot loaders still use this way.
1478
1479# Compressed boot loader in ROM.  Yes, we really want to ask about
1480# TEXT and BSS so we preserve their values in the config files.
1481config ZBOOT_ROM_TEXT
1482	hex "Compressed ROM boot loader base address"
1483	default 0x0
1484	help
1485	  The physical address at which the ROM-able zImage is to be
1486	  placed in the target.  Platforms which normally make use of
1487	  ROM-able zImage formats normally set this to a suitable
1488	  value in their defconfig file.
1489
1490	  If ZBOOT_ROM is not enabled, this has no effect.
1491
1492config ZBOOT_ROM_BSS
1493	hex "Compressed ROM boot loader BSS address"
1494	default 0x0
1495	help
1496	  The base address of an area of read/write memory in the target
1497	  for the ROM-able zImage which must be available while the
1498	  decompressor is running. It must be large enough to hold the
1499	  entire decompressed kernel plus an additional 128 KiB.
1500	  Platforms which normally make use of ROM-able zImage formats
1501	  normally set this to a suitable value in their defconfig file.
1502
1503	  If ZBOOT_ROM is not enabled, this has no effect.
1504
1505config ZBOOT_ROM
1506	bool "Compressed boot loader in ROM/flash"
1507	depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1508	depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1509	help
1510	  Say Y here if you intend to execute your compressed kernel image
1511	  (zImage) directly from ROM or flash.  If unsure, say N.
1512
1513config ARM_APPENDED_DTB
1514	bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1515	depends on OF
1516	help
1517	  With this option, the boot code will look for a device tree binary
1518	  (DTB) appended to zImage
1519	  (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1520
1521	  This is meant as a backward compatibility convenience for those
1522	  systems with a bootloader that can't be upgraded to accommodate
1523	  the documented boot protocol using a device tree.
1524
1525	  Beware that there is very little in terms of protection against
1526	  this option being confused by leftover garbage in memory that might
1527	  look like a DTB header after a reboot if no actual DTB is appended
1528	  to zImage.  Do not leave this option active in a production kernel
1529	  if you don't intend to always append a DTB.  Proper passing of the
1530	  location into r2 of a bootloader provided DTB is always preferable
1531	  to this option.
1532
1533config ARM_ATAG_DTB_COMPAT
1534	bool "Supplement the appended DTB with traditional ATAG information"
1535	depends on ARM_APPENDED_DTB
1536	help
1537	  Some old bootloaders can't be updated to a DTB capable one, yet
1538	  they provide ATAGs with memory configuration, the ramdisk address,
1539	  the kernel cmdline string, etc.  Such information is dynamically
1540	  provided by the bootloader and can't always be stored in a static
1541	  DTB.  To allow a device tree enabled kernel to be used with such
1542	  bootloaders, this option allows zImage to extract the information
1543	  from the ATAG list and store it at run time into the appended DTB.
1544
1545choice
1546	prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1547	default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1548
1549config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1550	bool "Use bootloader kernel arguments if available"
1551	help
1552	  Uses the command-line options passed by the boot loader instead of
1553	  the device tree bootargs property. If the boot loader doesn't provide
1554	  any, the device tree bootargs property will be used.
1555
1556config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1557	bool "Extend with bootloader kernel arguments"
1558	help
1559	  The command-line arguments provided by the boot loader will be
1560	  appended to the the device tree bootargs property.
1561
1562endchoice
1563
1564config CMDLINE
1565	string "Default kernel command string"
1566	default ""
1567	help
1568	  On some architectures (e.g. CATS), there is currently no way
1569	  for the boot loader to pass arguments to the kernel. For these
1570	  architectures, you should supply some command-line options at build
1571	  time by entering them here. As a minimum, you should specify the
1572	  memory size and the root device (e.g., mem=64M root=/dev/nfs).
1573
1574choice
1575	prompt "Kernel command line type" if CMDLINE != ""
1576	default CMDLINE_FROM_BOOTLOADER
1577
1578config CMDLINE_FROM_BOOTLOADER
1579	bool "Use bootloader kernel arguments if available"
1580	help
1581	  Uses the command-line options passed by the boot loader. If
1582	  the boot loader doesn't provide any, the default kernel command
1583	  string provided in CMDLINE will be used.
1584
1585config CMDLINE_EXTEND
1586	bool "Extend bootloader kernel arguments"
1587	help
1588	  The command-line arguments provided by the boot loader will be
1589	  appended to the default kernel command string.
1590
1591config CMDLINE_FORCE
1592	bool "Always use the default kernel command string"
1593	help
1594	  Always use the default kernel command string, even if the boot
1595	  loader passes other arguments to the kernel.
1596	  This is useful if you cannot or don't want to change the
1597	  command-line options your boot loader passes to the kernel.
1598endchoice
1599
1600config XIP_KERNEL
1601	bool "Kernel Execute-In-Place from ROM"
1602	depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
1603	depends on !ARM_PATCH_IDIV && !ARM_PATCH_PHYS_VIRT && !SMP_ON_UP
1604	help
1605	  Execute-In-Place allows the kernel to run from non-volatile storage
1606	  directly addressable by the CPU, such as NOR flash. This saves RAM
1607	  space since the text section of the kernel is not loaded from flash
1608	  to RAM.  Read-write sections, such as the data section and stack,
1609	  are still copied to RAM.  The XIP kernel is not compressed since
1610	  it has to run directly from flash, so it will take more space to
1611	  store it.  The flash address used to link the kernel object files,
1612	  and for storing it, is configuration dependent. Therefore, if you
1613	  say Y here, you must know the proper physical address where to
1614	  store the kernel image depending on your own flash memory usage.
1615
1616	  Also note that the make target becomes "make xipImage" rather than
1617	  "make zImage" or "make Image".  The final kernel binary to put in
1618	  ROM memory will be arch/arm/boot/xipImage.
1619
1620	  If unsure, say N.
1621
1622config XIP_PHYS_ADDR
1623	hex "XIP Kernel Physical Location"
1624	depends on XIP_KERNEL
1625	default "0x00080000"
1626	help
1627	  This is the physical address in your flash memory the kernel will
1628	  be linked for and stored to.  This address is dependent on your
1629	  own flash usage.
1630
1631config XIP_DEFLATED_DATA
1632	bool "Store kernel .data section compressed in ROM"
1633	depends on XIP_KERNEL
1634	select ZLIB_INFLATE
1635	help
1636	  Before the kernel is actually executed, its .data section has to be
1637	  copied to RAM from ROM. This option allows for storing that data
1638	  in compressed form and decompressed to RAM rather than merely being
1639	  copied, saving some precious ROM space. A possible drawback is a
1640	  slightly longer boot delay.
1641
1642config KEXEC
1643	bool "Kexec system call (EXPERIMENTAL)"
1644	depends on (!SMP || PM_SLEEP_SMP)
1645	depends on MMU
1646	select KEXEC_CORE
1647	help
1648	  kexec is a system call that implements the ability to shutdown your
1649	  current kernel, and to start another kernel.  It is like a reboot
1650	  but it is independent of the system firmware.   And like a reboot
1651	  you can start any kernel with it, not just Linux.
1652
1653	  It is an ongoing process to be certain the hardware in a machine
1654	  is properly shutdown, so do not be surprised if this code does not
1655	  initially work for you.
1656
1657config ATAGS_PROC
1658	bool "Export atags in procfs"
1659	depends on ATAGS && KEXEC
1660	default y
1661	help
1662	  Should the atags used to boot the kernel be exported in an "atags"
1663	  file in procfs. Useful with kexec.
1664
1665config CRASH_DUMP
1666	bool "Build kdump crash kernel (EXPERIMENTAL)"
1667	help
1668	  Generate crash dump after being started by kexec. This should
1669	  be normally only set in special crash dump kernels which are
1670	  loaded in the main kernel with kexec-tools into a specially
1671	  reserved region and then later executed after a crash by
1672	  kdump/kexec. The crash dump kernel must be compiled to a
1673	  memory address not used by the main kernel
1674
1675	  For more details see Documentation/admin-guide/kdump/kdump.rst
1676
1677config AUTO_ZRELADDR
1678	bool "Auto calculation of the decompressed kernel image address" if !ARCH_MULTIPLATFORM
1679	default !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
1680	help
1681	  ZRELADDR is the physical address where the decompressed kernel
1682	  image will be placed. If AUTO_ZRELADDR is selected, the address
1683	  will be determined at run-time, either by masking the current IP
1684	  with 0xf8000000, or, if invalid, from the DTB passed in r2.
1685	  This assumes the zImage being placed in the first 128MB from
1686	  start of memory.
1687
1688config EFI_STUB
1689	bool
1690
1691config EFI
1692	bool "UEFI runtime support"
1693	depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
1694	select UCS2_STRING
1695	select EFI_PARAMS_FROM_FDT
1696	select EFI_STUB
1697	select EFI_GENERIC_STUB
1698	select EFI_RUNTIME_WRAPPERS
1699	help
1700	  This option provides support for runtime services provided
1701	  by UEFI firmware (such as non-volatile variables, realtime
1702	  clock, and platform reset). A UEFI stub is also provided to
1703	  allow the kernel to be booted as an EFI application. This
1704	  is only useful for kernels that may run on systems that have
1705	  UEFI firmware.
1706
1707config DMI
1708	bool "Enable support for SMBIOS (DMI) tables"
1709	depends on EFI
1710	default y
1711	help
1712	  This enables SMBIOS/DMI feature for systems.
1713
1714	  This option is only useful on systems that have UEFI firmware.
1715	  However, even with this option, the resultant kernel should
1716	  continue to boot on existing non-UEFI platforms.
1717
1718	  NOTE: This does *NOT* enable or encourage the use of DMI quirks,
1719	  i.e., the the practice of identifying the platform via DMI to
1720	  decide whether certain workarounds for buggy hardware and/or
1721	  firmware need to be enabled. This would require the DMI subsystem
1722	  to be enabled much earlier than we do on ARM, which is non-trivial.
1723
1724endmenu
1725
1726menu "CPU Power Management"
1727
1728source "drivers/cpufreq/Kconfig"
1729
1730source "drivers/cpuidle/Kconfig"
1731
1732endmenu
1733
1734menu "Floating point emulation"
1735
1736comment "At least one emulation must be selected"
1737
1738config FPE_NWFPE
1739	bool "NWFPE math emulation"
1740	depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
1741	help
1742	  Say Y to include the NWFPE floating point emulator in the kernel.
1743	  This is necessary to run most binaries. Linux does not currently
1744	  support floating point hardware so you need to say Y here even if
1745	  your machine has an FPA or floating point co-processor podule.
1746
1747	  You may say N here if you are going to load the Acorn FPEmulator
1748	  early in the bootup.
1749
1750config FPE_NWFPE_XP
1751	bool "Support extended precision"
1752	depends on FPE_NWFPE
1753	help
1754	  Say Y to include 80-bit support in the kernel floating-point
1755	  emulator.  Otherwise, only 32 and 64-bit support is compiled in.
1756	  Note that gcc does not generate 80-bit operations by default,
1757	  so in most cases this option only enlarges the size of the
1758	  floating point emulator without any good reason.
1759
1760	  You almost surely want to say N here.
1761
1762config FPE_FASTFPE
1763	bool "FastFPE math emulation (EXPERIMENTAL)"
1764	depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
1765	help
1766	  Say Y here to include the FAST floating point emulator in the kernel.
1767	  This is an experimental much faster emulator which now also has full
1768	  precision for the mantissa.  It does not support any exceptions.
1769	  It is very simple, and approximately 3-6 times faster than NWFPE.
1770
1771	  It should be sufficient for most programs.  It may be not suitable
1772	  for scientific calculations, but you have to check this for yourself.
1773	  If you do not feel you need a faster FP emulation you should better
1774	  choose NWFPE.
1775
1776config VFP
1777	bool "VFP-format floating point maths"
1778	depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1779	help
1780	  Say Y to include VFP support code in the kernel. This is needed
1781	  if your hardware includes a VFP unit.
1782
1783	  Please see <file:Documentation/arm/vfp/release-notes.rst> for
1784	  release notes and additional status information.
1785
1786	  Say N if your target does not have VFP hardware.
1787
1788config VFPv3
1789	bool
1790	depends on VFP
1791	default y if CPU_V7
1792
1793config NEON
1794	bool "Advanced SIMD (NEON) Extension support"
1795	depends on VFPv3 && CPU_V7
1796	help
1797	  Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1798	  Extension.
1799
1800config KERNEL_MODE_NEON
1801	bool "Support for NEON in kernel mode"
1802	depends on NEON && AEABI
1803	help
1804	  Say Y to include support for NEON in kernel mode.
1805
1806endmenu
1807
1808menu "Power management options"
1809
1810source "kernel/power/Kconfig"
1811
1812config ARCH_SUSPEND_POSSIBLE
1813	depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
1814		CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
1815	def_bool y
1816
1817config ARM_CPU_SUSPEND
1818	def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
1819	depends on ARCH_SUSPEND_POSSIBLE
1820
1821config ARCH_HIBERNATION_POSSIBLE
1822	bool
1823	depends on MMU
1824	default y if ARCH_SUSPEND_POSSIBLE
1825
1826endmenu
1827
1828source "arch/arm/Kconfig.assembler"
1829