xref: /linux/arch/arm64/Kconfig (revision 156010ed9c2ac1e9df6c11b1f688cf8a6e0152e6)
1# SPDX-License-Identifier: GPL-2.0-only
2config ARM64
3	def_bool y
4	select ACPI_APMT if ACPI
5	select ACPI_CCA_REQUIRED if ACPI
6	select ACPI_GENERIC_GSI if ACPI
7	select ACPI_GTDT if ACPI
8	select ACPI_IORT if ACPI
9	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
10	select ACPI_MCFG if (ACPI && PCI)
11	select ACPI_SPCR_TABLE if ACPI
12	select ACPI_PPTT if ACPI
13	select ARCH_HAS_DEBUG_WX
14	select ARCH_BINFMT_ELF_EXTRA_PHDRS
15	select ARCH_BINFMT_ELF_STATE
16	select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
17	select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
18	select ARCH_ENABLE_MEMORY_HOTPLUG
19	select ARCH_ENABLE_MEMORY_HOTREMOVE
20	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
21	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
22	select ARCH_HAS_CACHE_LINE_SIZE
23	select ARCH_HAS_CURRENT_STACK_POINTER
24	select ARCH_HAS_DEBUG_VIRTUAL
25	select ARCH_HAS_DEBUG_VM_PGTABLE
26	select ARCH_HAS_DMA_PREP_COHERENT
27	select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
28	select ARCH_HAS_FAST_MULTIPLIER
29	select ARCH_HAS_FORTIFY_SOURCE
30	select ARCH_HAS_GCOV_PROFILE_ALL
31	select ARCH_HAS_GIGANTIC_PAGE
32	select ARCH_HAS_KCOV
33	select ARCH_HAS_KEEPINITRD
34	select ARCH_HAS_MEMBARRIER_SYNC_CORE
35	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
36	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
37	select ARCH_HAS_PTE_DEVMAP
38	select ARCH_HAS_PTE_SPECIAL
39	select ARCH_HAS_SETUP_DMA_OPS
40	select ARCH_HAS_SET_DIRECT_MAP
41	select ARCH_HAS_SET_MEMORY
42	select ARCH_STACKWALK
43	select ARCH_HAS_STRICT_KERNEL_RWX
44	select ARCH_HAS_STRICT_MODULE_RWX
45	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
46	select ARCH_HAS_SYNC_DMA_FOR_CPU
47	select ARCH_HAS_SYSCALL_WRAPPER
48	select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
49	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
50	select ARCH_HAS_ZONE_DMA_SET if EXPERT
51	select ARCH_HAVE_ELF_PROT
52	select ARCH_HAVE_NMI_SAFE_CMPXCHG
53	select ARCH_HAVE_TRACE_MMIO_ACCESS
54	select ARCH_INLINE_READ_LOCK if !PREEMPTION
55	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
56	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
57	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
58	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
59	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
60	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
61	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
62	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
63	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
64	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
65	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
66	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
67	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
68	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
69	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
70	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
71	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
72	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
73	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
74	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
75	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
76	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
77	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
78	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
79	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
80	select ARCH_KEEP_MEMBLOCK
81	select ARCH_USE_CMPXCHG_LOCKREF
82	select ARCH_USE_GNU_PROPERTY
83	select ARCH_USE_MEMTEST
84	select ARCH_USE_QUEUED_RWLOCKS
85	select ARCH_USE_QUEUED_SPINLOCKS
86	select ARCH_USE_SYM_ANNOTATIONS
87	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
88	select ARCH_SUPPORTS_HUGETLBFS
89	select ARCH_SUPPORTS_MEMORY_FAILURE
90	select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
91	select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
92	select ARCH_SUPPORTS_LTO_CLANG_THIN
93	select ARCH_SUPPORTS_CFI_CLANG
94	select ARCH_SUPPORTS_ATOMIC_RMW
95	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
96	select ARCH_SUPPORTS_NUMA_BALANCING
97	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
98	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
99	select ARCH_WANT_DEFAULT_BPF_JIT
100	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
101	select ARCH_WANT_FRAME_POINTERS
102	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
103	select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
104	select ARCH_WANT_LD_ORPHAN_WARN
105	select ARCH_WANTS_NO_INSTR
106	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
107	select ARCH_HAS_UBSAN_SANITIZE_ALL
108	select ARM_AMBA
109	select ARM_ARCH_TIMER
110	select ARM_GIC
111	select AUDIT_ARCH_COMPAT_GENERIC
112	select ARM_GIC_V2M if PCI
113	select ARM_GIC_V3
114	select ARM_GIC_V3_ITS if PCI
115	select ARM_PSCI_FW
116	select BUILDTIME_TABLE_SORT
117	select CLONE_BACKWARDS
118	select COMMON_CLK
119	select CPU_PM if (SUSPEND || CPU_IDLE)
120	select CRC32
121	select DCACHE_WORD_ACCESS
122	select DYNAMIC_FTRACE if FUNCTION_TRACER
123	select DMA_DIRECT_REMAP
124	select EDAC_SUPPORT
125	select FRAME_POINTER
126	select FUNCTION_ALIGNMENT_4B
127	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
128	select GENERIC_ALLOCATOR
129	select GENERIC_ARCH_TOPOLOGY
130	select GENERIC_CLOCKEVENTS_BROADCAST
131	select GENERIC_CPU_AUTOPROBE
132	select GENERIC_CPU_VULNERABILITIES
133	select GENERIC_EARLY_IOREMAP
134	select GENERIC_IDLE_POLL_SETUP
135	select GENERIC_IOREMAP
136	select GENERIC_IRQ_IPI
137	select GENERIC_IRQ_PROBE
138	select GENERIC_IRQ_SHOW
139	select GENERIC_IRQ_SHOW_LEVEL
140	select GENERIC_LIB_DEVMEM_IS_ALLOWED
141	select GENERIC_PCI_IOMAP
142	select GENERIC_PTDUMP
143	select GENERIC_SCHED_CLOCK
144	select GENERIC_SMP_IDLE_THREAD
145	select GENERIC_TIME_VSYSCALL
146	select GENERIC_GETTIMEOFDAY
147	select GENERIC_VDSO_TIME_NS
148	select HARDIRQS_SW_RESEND
149	select HAVE_MOVE_PMD
150	select HAVE_MOVE_PUD
151	select HAVE_PCI
152	select HAVE_ACPI_APEI if (ACPI && EFI)
153	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
154	select HAVE_ARCH_AUDITSYSCALL
155	select HAVE_ARCH_BITREVERSE
156	select HAVE_ARCH_COMPILER_H
157	select HAVE_ARCH_HUGE_VMALLOC
158	select HAVE_ARCH_HUGE_VMAP
159	select HAVE_ARCH_JUMP_LABEL
160	select HAVE_ARCH_JUMP_LABEL_RELATIVE
161	select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
162	select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
163	select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
164	select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
165	# Some instrumentation may be unsound, hence EXPERT
166	select HAVE_ARCH_KCSAN if EXPERT
167	select HAVE_ARCH_KFENCE
168	select HAVE_ARCH_KGDB
169	select HAVE_ARCH_MMAP_RND_BITS
170	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
171	select HAVE_ARCH_PREL32_RELOCATIONS
172	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
173	select HAVE_ARCH_SECCOMP_FILTER
174	select HAVE_ARCH_STACKLEAK
175	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
176	select HAVE_ARCH_TRACEHOOK
177	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
178	select HAVE_ARCH_VMAP_STACK
179	select HAVE_ARM_SMCCC
180	select HAVE_ASM_MODVERSIONS
181	select HAVE_EBPF_JIT
182	select HAVE_C_RECORDMCOUNT
183	select HAVE_CMPXCHG_DOUBLE
184	select HAVE_CMPXCHG_LOCAL
185	select HAVE_CONTEXT_TRACKING_USER
186	select HAVE_DEBUG_KMEMLEAK
187	select HAVE_DMA_CONTIGUOUS
188	select HAVE_DYNAMIC_FTRACE
189	select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
190		if $(cc-option,-fpatchable-function-entry=2)
191	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
192		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG)
193	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
194		if DYNAMIC_FTRACE_WITH_ARGS
195	select HAVE_EFFICIENT_UNALIGNED_ACCESS
196	select HAVE_FAST_GUP
197	select HAVE_FTRACE_MCOUNT_RECORD
198	select HAVE_FUNCTION_TRACER
199	select HAVE_FUNCTION_ERROR_INJECTION
200	select HAVE_FUNCTION_GRAPH_TRACER
201	select HAVE_GCC_PLUGINS
202	select HAVE_HW_BREAKPOINT if PERF_EVENTS
203	select HAVE_IOREMAP_PROT
204	select HAVE_IRQ_TIME_ACCOUNTING
205	select HAVE_KVM
206	select HAVE_NMI
207	select HAVE_PERF_EVENTS
208	select HAVE_PERF_REGS
209	select HAVE_PERF_USER_STACK_DUMP
210	select HAVE_PREEMPT_DYNAMIC_KEY
211	select HAVE_REGS_AND_STACK_ACCESS_API
212	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
213	select HAVE_FUNCTION_ARG_ACCESS_API
214	select MMU_GATHER_RCU_TABLE_FREE
215	select HAVE_RSEQ
216	select HAVE_STACKPROTECTOR
217	select HAVE_SYSCALL_TRACEPOINTS
218	select HAVE_KPROBES
219	select HAVE_KRETPROBES
220	select HAVE_GENERIC_VDSO
221	select IRQ_DOMAIN
222	select IRQ_FORCED_THREADING
223	select KASAN_VMALLOC if KASAN
224	select MODULES_USE_ELF_RELA
225	select NEED_DMA_MAP_STATE
226	select NEED_SG_DMA_LENGTH
227	select OF
228	select OF_EARLY_FLATTREE
229	select PCI_DOMAINS_GENERIC if PCI
230	select PCI_ECAM if (ACPI && PCI)
231	select PCI_SYSCALL if PCI
232	select POWER_RESET
233	select POWER_SUPPLY
234	select SPARSE_IRQ
235	select SWIOTLB
236	select SYSCTL_EXCEPTION_TRACE
237	select THREAD_INFO_IN_TASK
238	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
239	select TRACE_IRQFLAGS_SUPPORT
240	select TRACE_IRQFLAGS_NMI_SUPPORT
241	select HAVE_SOFTIRQ_ON_OWN_STACK
242	help
243	  ARM 64-bit (AArch64) Linux support.
244
245config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
246	def_bool CC_IS_CLANG
247	# https://github.com/ClangBuiltLinux/linux/issues/1507
248	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
249	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
250
251config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
252	def_bool CC_IS_GCC
253	depends on $(cc-option,-fpatchable-function-entry=2)
254	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
255
256config 64BIT
257	def_bool y
258
259config MMU
260	def_bool y
261
262config ARM64_PAGE_SHIFT
263	int
264	default 16 if ARM64_64K_PAGES
265	default 14 if ARM64_16K_PAGES
266	default 12
267
268config ARM64_CONT_PTE_SHIFT
269	int
270	default 5 if ARM64_64K_PAGES
271	default 7 if ARM64_16K_PAGES
272	default 4
273
274config ARM64_CONT_PMD_SHIFT
275	int
276	default 5 if ARM64_64K_PAGES
277	default 5 if ARM64_16K_PAGES
278	default 4
279
280config ARCH_MMAP_RND_BITS_MIN
281	default 14 if ARM64_64K_PAGES
282	default 16 if ARM64_16K_PAGES
283	default 18
284
285# max bits determined by the following formula:
286#  VA_BITS - PAGE_SHIFT - 3
287config ARCH_MMAP_RND_BITS_MAX
288	default 19 if ARM64_VA_BITS=36
289	default 24 if ARM64_VA_BITS=39
290	default 27 if ARM64_VA_BITS=42
291	default 30 if ARM64_VA_BITS=47
292	default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
293	default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
294	default 33 if ARM64_VA_BITS=48
295	default 14 if ARM64_64K_PAGES
296	default 16 if ARM64_16K_PAGES
297	default 18
298
299config ARCH_MMAP_RND_COMPAT_BITS_MIN
300	default 7 if ARM64_64K_PAGES
301	default 9 if ARM64_16K_PAGES
302	default 11
303
304config ARCH_MMAP_RND_COMPAT_BITS_MAX
305	default 16
306
307config NO_IOPORT_MAP
308	def_bool y if !PCI
309
310config STACKTRACE_SUPPORT
311	def_bool y
312
313config ILLEGAL_POINTER_VALUE
314	hex
315	default 0xdead000000000000
316
317config LOCKDEP_SUPPORT
318	def_bool y
319
320config GENERIC_BUG
321	def_bool y
322	depends on BUG
323
324config GENERIC_BUG_RELATIVE_POINTERS
325	def_bool y
326	depends on GENERIC_BUG
327
328config GENERIC_HWEIGHT
329	def_bool y
330
331config GENERIC_CSUM
332	def_bool y
333
334config GENERIC_CALIBRATE_DELAY
335	def_bool y
336
337config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
338	def_bool y
339
340config SMP
341	def_bool y
342
343config KERNEL_MODE_NEON
344	def_bool y
345
346config FIX_EARLYCON_MEM
347	def_bool y
348
349config PGTABLE_LEVELS
350	int
351	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
352	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
353	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
354	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
355	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
356	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
357
358config ARCH_SUPPORTS_UPROBES
359	def_bool y
360
361config ARCH_PROC_KCORE_TEXT
362	def_bool y
363
364config BROKEN_GAS_INST
365	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
366
367config KASAN_SHADOW_OFFSET
368	hex
369	depends on KASAN_GENERIC || KASAN_SW_TAGS
370	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
371	default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
372	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
373	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
374	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
375	default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
376	default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
377	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
378	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
379	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
380	default 0xffffffffffffffff
381
382config UNWIND_TABLES
383	bool
384
385source "arch/arm64/Kconfig.platforms"
386
387menu "Kernel Features"
388
389menu "ARM errata workarounds via the alternatives framework"
390
391config ARM64_WORKAROUND_CLEAN_CACHE
392	bool
393
394config ARM64_ERRATUM_826319
395	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
396	default y
397	select ARM64_WORKAROUND_CLEAN_CACHE
398	help
399	  This option adds an alternative code sequence to work around ARM
400	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
401	  AXI master interface and an L2 cache.
402
403	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
404	  and is unable to accept a certain write via this interface, it will
405	  not progress on read data presented on the read data channel and the
406	  system can deadlock.
407
408	  The workaround promotes data cache clean instructions to
409	  data cache clean-and-invalidate.
410	  Please note that this does not necessarily enable the workaround,
411	  as it depends on the alternative framework, which will only patch
412	  the kernel if an affected CPU is detected.
413
414	  If unsure, say Y.
415
416config ARM64_ERRATUM_827319
417	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
418	default y
419	select ARM64_WORKAROUND_CLEAN_CACHE
420	help
421	  This option adds an alternative code sequence to work around ARM
422	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
423	  master interface and an L2 cache.
424
425	  Under certain conditions this erratum can cause a clean line eviction
426	  to occur at the same time as another transaction to the same address
427	  on the AMBA 5 CHI interface, which can cause data corruption if the
428	  interconnect reorders the two transactions.
429
430	  The workaround promotes data cache clean instructions to
431	  data cache clean-and-invalidate.
432	  Please note that this does not necessarily enable the workaround,
433	  as it depends on the alternative framework, which will only patch
434	  the kernel if an affected CPU is detected.
435
436	  If unsure, say Y.
437
438config ARM64_ERRATUM_824069
439	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
440	default y
441	select ARM64_WORKAROUND_CLEAN_CACHE
442	help
443	  This option adds an alternative code sequence to work around ARM
444	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
445	  to a coherent interconnect.
446
447	  If a Cortex-A53 processor is executing a store or prefetch for
448	  write instruction at the same time as a processor in another
449	  cluster is executing a cache maintenance operation to the same
450	  address, then this erratum might cause a clean cache line to be
451	  incorrectly marked as dirty.
452
453	  The workaround promotes data cache clean instructions to
454	  data cache clean-and-invalidate.
455	  Please note that this option does not necessarily enable the
456	  workaround, as it depends on the alternative framework, which will
457	  only patch the kernel if an affected CPU is detected.
458
459	  If unsure, say Y.
460
461config ARM64_ERRATUM_819472
462	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
463	default y
464	select ARM64_WORKAROUND_CLEAN_CACHE
465	help
466	  This option adds an alternative code sequence to work around ARM
467	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
468	  present when it is connected to a coherent interconnect.
469
470	  If the processor is executing a load and store exclusive sequence at
471	  the same time as a processor in another cluster is executing a cache
472	  maintenance operation to the same address, then this erratum might
473	  cause data corruption.
474
475	  The workaround promotes data cache clean instructions to
476	  data cache clean-and-invalidate.
477	  Please note that this does not necessarily enable the workaround,
478	  as it depends on the alternative framework, which will only patch
479	  the kernel if an affected CPU is detected.
480
481	  If unsure, say Y.
482
483config ARM64_ERRATUM_832075
484	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
485	default y
486	help
487	  This option adds an alternative code sequence to work around ARM
488	  erratum 832075 on Cortex-A57 parts up to r1p2.
489
490	  Affected Cortex-A57 parts might deadlock when exclusive load/store
491	  instructions to Write-Back memory are mixed with Device loads.
492
493	  The workaround is to promote device loads to use Load-Acquire
494	  semantics.
495	  Please note that this does not necessarily enable the workaround,
496	  as it depends on the alternative framework, which will only patch
497	  the kernel if an affected CPU is detected.
498
499	  If unsure, say Y.
500
501config ARM64_ERRATUM_834220
502	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
503	depends on KVM
504	default y
505	help
506	  This option adds an alternative code sequence to work around ARM
507	  erratum 834220 on Cortex-A57 parts up to r1p2.
508
509	  Affected Cortex-A57 parts might report a Stage 2 translation
510	  fault as the result of a Stage 1 fault for load crossing a
511	  page boundary when there is a permission or device memory
512	  alignment fault at Stage 1 and a translation fault at Stage 2.
513
514	  The workaround is to verify that the Stage 1 translation
515	  doesn't generate a fault before handling the Stage 2 fault.
516	  Please note that this does not necessarily enable the workaround,
517	  as it depends on the alternative framework, which will only patch
518	  the kernel if an affected CPU is detected.
519
520	  If unsure, say Y.
521
522config ARM64_ERRATUM_1742098
523	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
524	depends on COMPAT
525	default y
526	help
527	  This option removes the AES hwcap for aarch32 user-space to
528	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
529
530	  Affected parts may corrupt the AES state if an interrupt is
531	  taken between a pair of AES instructions. These instructions
532	  are only present if the cryptography extensions are present.
533	  All software should have a fallback implementation for CPUs
534	  that don't implement the cryptography extensions.
535
536	  If unsure, say Y.
537
538config ARM64_ERRATUM_845719
539	bool "Cortex-A53: 845719: a load might read incorrect data"
540	depends on COMPAT
541	default y
542	help
543	  This option adds an alternative code sequence to work around ARM
544	  erratum 845719 on Cortex-A53 parts up to r0p4.
545
546	  When running a compat (AArch32) userspace on an affected Cortex-A53
547	  part, a load at EL0 from a virtual address that matches the bottom 32
548	  bits of the virtual address used by a recent load at (AArch64) EL1
549	  might return incorrect data.
550
551	  The workaround is to write the contextidr_el1 register on exception
552	  return to a 32-bit task.
553	  Please note that this does not necessarily enable the workaround,
554	  as it depends on the alternative framework, which will only patch
555	  the kernel if an affected CPU is detected.
556
557	  If unsure, say Y.
558
559config ARM64_ERRATUM_843419
560	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
561	default y
562	select ARM64_MODULE_PLTS if MODULES
563	help
564	  This option links the kernel with '--fix-cortex-a53-843419' and
565	  enables PLT support to replace certain ADRP instructions, which can
566	  cause subsequent memory accesses to use an incorrect address on
567	  Cortex-A53 parts up to r0p4.
568
569	  If unsure, say Y.
570
571config ARM64_LD_HAS_FIX_ERRATUM_843419
572	def_bool $(ld-option,--fix-cortex-a53-843419)
573
574config ARM64_ERRATUM_1024718
575	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
576	default y
577	help
578	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
579
580	  Affected Cortex-A55 cores (all revisions) could cause incorrect
581	  update of the hardware dirty bit when the DBM/AP bits are updated
582	  without a break-before-make. The workaround is to disable the usage
583	  of hardware DBM locally on the affected cores. CPUs not affected by
584	  this erratum will continue to use the feature.
585
586	  If unsure, say Y.
587
588config ARM64_ERRATUM_1418040
589	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
590	default y
591	depends on COMPAT
592	help
593	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
594	  errata 1188873 and 1418040.
595
596	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
597	  cause register corruption when accessing the timer registers
598	  from AArch32 userspace.
599
600	  If unsure, say Y.
601
602config ARM64_WORKAROUND_SPECULATIVE_AT
603	bool
604
605config ARM64_ERRATUM_1165522
606	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
607	default y
608	select ARM64_WORKAROUND_SPECULATIVE_AT
609	help
610	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
611
612	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
613	  corrupted TLBs by speculating an AT instruction during a guest
614	  context switch.
615
616	  If unsure, say Y.
617
618config ARM64_ERRATUM_1319367
619	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
620	default y
621	select ARM64_WORKAROUND_SPECULATIVE_AT
622	help
623	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
624	  and A72 erratum 1319367
625
626	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
627	  speculating an AT instruction during a guest context switch.
628
629	  If unsure, say Y.
630
631config ARM64_ERRATUM_1530923
632	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
633	default y
634	select ARM64_WORKAROUND_SPECULATIVE_AT
635	help
636	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
637
638	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
639	  corrupted TLBs by speculating an AT instruction during a guest
640	  context switch.
641
642	  If unsure, say Y.
643
644config ARM64_WORKAROUND_REPEAT_TLBI
645	bool
646
647config ARM64_ERRATUM_2441007
648	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
649	default y
650	select ARM64_WORKAROUND_REPEAT_TLBI
651	help
652	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
653
654	  Under very rare circumstances, affected Cortex-A55 CPUs
655	  may not handle a race between a break-before-make sequence on one
656	  CPU, and another CPU accessing the same page. This could allow a
657	  store to a page that has been unmapped.
658
659	  Work around this by adding the affected CPUs to the list that needs
660	  TLB sequences to be done twice.
661
662	  If unsure, say Y.
663
664config ARM64_ERRATUM_1286807
665	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
666	default y
667	select ARM64_WORKAROUND_REPEAT_TLBI
668	help
669	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
670
671	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
672	  address for a cacheable mapping of a location is being
673	  accessed by a core while another core is remapping the virtual
674	  address to a new physical page using the recommended
675	  break-before-make sequence, then under very rare circumstances
676	  TLBI+DSB completes before a read using the translation being
677	  invalidated has been observed by other observers. The
678	  workaround repeats the TLBI+DSB operation.
679
680config ARM64_ERRATUM_1463225
681	bool "Cortex-A76: Software Step might prevent interrupt recognition"
682	default y
683	help
684	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
685
686	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
687	  of a system call instruction (SVC) can prevent recognition of
688	  subsequent interrupts when software stepping is disabled in the
689	  exception handler of the system call and either kernel debugging
690	  is enabled or VHE is in use.
691
692	  Work around the erratum by triggering a dummy step exception
693	  when handling a system call from a task that is being stepped
694	  in a VHE configuration of the kernel.
695
696	  If unsure, say Y.
697
698config ARM64_ERRATUM_1542419
699	bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
700	default y
701	help
702	  This option adds a workaround for ARM Neoverse-N1 erratum
703	  1542419.
704
705	  Affected Neoverse-N1 cores could execute a stale instruction when
706	  modified by another CPU. The workaround depends on a firmware
707	  counterpart.
708
709	  Workaround the issue by hiding the DIC feature from EL0. This
710	  forces user-space to perform cache maintenance.
711
712	  If unsure, say Y.
713
714config ARM64_ERRATUM_1508412
715	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
716	default y
717	help
718	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
719
720	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
721	  of a store-exclusive or read of PAR_EL1 and a load with device or
722	  non-cacheable memory attributes. The workaround depends on a firmware
723	  counterpart.
724
725	  KVM guests must also have the workaround implemented or they can
726	  deadlock the system.
727
728	  Work around the issue by inserting DMB SY barriers around PAR_EL1
729	  register reads and warning KVM users. The DMB barrier is sufficient
730	  to prevent a speculative PAR_EL1 read.
731
732	  If unsure, say Y.
733
734config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
735	bool
736
737config ARM64_ERRATUM_2051678
738	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
739	default y
740	help
741	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
742	  Affected Cortex-A510 might not respect the ordering rules for
743	  hardware update of the page table's dirty bit. The workaround
744	  is to not enable the feature on affected CPUs.
745
746	  If unsure, say Y.
747
748config ARM64_ERRATUM_2077057
749	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
750	default y
751	help
752	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
753	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
754	  expected, but a Pointer Authentication trap is taken instead. The
755	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
756	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
757
758	  This can only happen when EL2 is stepping EL1.
759
760	  When these conditions occur, the SPSR_EL2 value is unchanged from the
761	  previous guest entry, and can be restored from the in-memory copy.
762
763	  If unsure, say Y.
764
765config ARM64_ERRATUM_2658417
766	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
767	default y
768	help
769	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
770	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
771	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
772	  A510 CPUs are using shared neon hardware. As the sharing is not
773	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
774	  user-space should not be using these instructions.
775
776	  If unsure, say Y.
777
778config ARM64_ERRATUM_2119858
779	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
780	default y
781	depends on CORESIGHT_TRBE
782	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
783	help
784	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
785
786	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
787	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
788	  the event of a WRAP event.
789
790	  Work around the issue by always making sure we move the TRBPTR_EL1 by
791	  256 bytes before enabling the buffer and filling the first 256 bytes of
792	  the buffer with ETM ignore packets upon disabling.
793
794	  If unsure, say Y.
795
796config ARM64_ERRATUM_2139208
797	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
798	default y
799	depends on CORESIGHT_TRBE
800	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
801	help
802	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
803
804	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
805	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
806	  the event of a WRAP event.
807
808	  Work around the issue by always making sure we move the TRBPTR_EL1 by
809	  256 bytes before enabling the buffer and filling the first 256 bytes of
810	  the buffer with ETM ignore packets upon disabling.
811
812	  If unsure, say Y.
813
814config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
815	bool
816
817config ARM64_ERRATUM_2054223
818	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
819	default y
820	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
821	help
822	  Enable workaround for ARM Cortex-A710 erratum 2054223
823
824	  Affected cores may fail to flush the trace data on a TSB instruction, when
825	  the PE is in trace prohibited state. This will cause losing a few bytes
826	  of the trace cached.
827
828	  Workaround is to issue two TSB consecutively on affected cores.
829
830	  If unsure, say Y.
831
832config ARM64_ERRATUM_2067961
833	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
834	default y
835	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
836	help
837	  Enable workaround for ARM Neoverse-N2 erratum 2067961
838
839	  Affected cores may fail to flush the trace data on a TSB instruction, when
840	  the PE is in trace prohibited state. This will cause losing a few bytes
841	  of the trace cached.
842
843	  Workaround is to issue two TSB consecutively on affected cores.
844
845	  If unsure, say Y.
846
847config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
848	bool
849
850config ARM64_ERRATUM_2253138
851	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
852	depends on CORESIGHT_TRBE
853	default y
854	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
855	help
856	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
857
858	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
859	  for TRBE. Under some conditions, the TRBE might generate a write to the next
860	  virtually addressed page following the last page of the TRBE address space
861	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
862
863	  Work around this in the driver by always making sure that there is a
864	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
865
866	  If unsure, say Y.
867
868config ARM64_ERRATUM_2224489
869	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
870	depends on CORESIGHT_TRBE
871	default y
872	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
873	help
874	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
875
876	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
877	  for TRBE. Under some conditions, the TRBE might generate a write to the next
878	  virtually addressed page following the last page of the TRBE address space
879	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
880
881	  Work around this in the driver by always making sure that there is a
882	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
883
884	  If unsure, say Y.
885
886config ARM64_ERRATUM_2441009
887	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
888	default y
889	select ARM64_WORKAROUND_REPEAT_TLBI
890	help
891	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
892
893	  Under very rare circumstances, affected Cortex-A510 CPUs
894	  may not handle a race between a break-before-make sequence on one
895	  CPU, and another CPU accessing the same page. This could allow a
896	  store to a page that has been unmapped.
897
898	  Work around this by adding the affected CPUs to the list that needs
899	  TLB sequences to be done twice.
900
901	  If unsure, say Y.
902
903config ARM64_ERRATUM_2064142
904	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
905	depends on CORESIGHT_TRBE
906	default y
907	help
908	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
909
910	  Affected Cortex-A510 core might fail to write into system registers after the
911	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
912	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
913	  and TRBTRG_EL1 will be ignored and will not be effected.
914
915	  Work around this in the driver by executing TSB CSYNC and DSB after collection
916	  is stopped and before performing a system register write to one of the affected
917	  registers.
918
919	  If unsure, say Y.
920
921config ARM64_ERRATUM_2038923
922	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
923	depends on CORESIGHT_TRBE
924	default y
925	help
926	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
927
928	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
929	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
930	  might be corrupted. This happens after TRBE buffer has been enabled by setting
931	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
932	  execution changes from a context, in which trace is prohibited to one where it
933	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
934	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
935	  the trace buffer state might be corrupted.
936
937	  Work around this in the driver by preventing an inconsistent view of whether the
938	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
939	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
940	  two ISB instructions if no ERET is to take place.
941
942	  If unsure, say Y.
943
944config ARM64_ERRATUM_1902691
945	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
946	depends on CORESIGHT_TRBE
947	default y
948	help
949	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
950
951	  Affected Cortex-A510 core might cause trace data corruption, when being written
952	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
953	  trace data.
954
955	  Work around this problem in the driver by just preventing TRBE initialization on
956	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
957	  on such implementations. This will cover the kernel for any firmware that doesn't
958	  do this already.
959
960	  If unsure, say Y.
961
962config ARM64_ERRATUM_2457168
963	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
964	depends on ARM64_AMU_EXTN
965	default y
966	help
967	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
968
969	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
970	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
971	  incorrectly giving a significantly higher output value.
972
973	  Work around this problem by returning 0 when reading the affected counter in
974	  key locations that results in disabling all users of this counter. This effect
975	  is the same to firmware disabling affected counters.
976
977	  If unsure, say Y.
978
979config CAVIUM_ERRATUM_22375
980	bool "Cavium erratum 22375, 24313"
981	default y
982	help
983	  Enable workaround for errata 22375 and 24313.
984
985	  This implements two gicv3-its errata workarounds for ThunderX. Both
986	  with a small impact affecting only ITS table allocation.
987
988	    erratum 22375: only alloc 8MB table size
989	    erratum 24313: ignore memory access type
990
991	  The fixes are in ITS initialization and basically ignore memory access
992	  type and table size provided by the TYPER and BASER registers.
993
994	  If unsure, say Y.
995
996config CAVIUM_ERRATUM_23144
997	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
998	depends on NUMA
999	default y
1000	help
1001	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1002
1003	  If unsure, say Y.
1004
1005config CAVIUM_ERRATUM_23154
1006	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1007	default y
1008	help
1009	  The ThunderX GICv3 implementation requires a modified version for
1010	  reading the IAR status to ensure data synchronization
1011	  (access to icc_iar1_el1 is not sync'ed before and after).
1012
1013	  It also suffers from erratum 38545 (also present on Marvell's
1014	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1015	  spuriously presented to the CPU interface.
1016
1017	  If unsure, say Y.
1018
1019config CAVIUM_ERRATUM_27456
1020	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1021	default y
1022	help
1023	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1024	  instructions may cause the icache to become corrupted if it
1025	  contains data for a non-current ASID.  The fix is to
1026	  invalidate the icache when changing the mm context.
1027
1028	  If unsure, say Y.
1029
1030config CAVIUM_ERRATUM_30115
1031	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1032	default y
1033	help
1034	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1035	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1036	  interrupts in host. Trapping both GICv3 group-0 and group-1
1037	  accesses sidesteps the issue.
1038
1039	  If unsure, say Y.
1040
1041config CAVIUM_TX2_ERRATUM_219
1042	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1043	default y
1044	help
1045	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1046	  TTBR update and the corresponding context synchronizing operation can
1047	  cause a spurious Data Abort to be delivered to any hardware thread in
1048	  the CPU core.
1049
1050	  Work around the issue by avoiding the problematic code sequence and
1051	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1052	  trap handler performs the corresponding register access, skips the
1053	  instruction and ensures context synchronization by virtue of the
1054	  exception return.
1055
1056	  If unsure, say Y.
1057
1058config FUJITSU_ERRATUM_010001
1059	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1060	default y
1061	help
1062	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1063	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1064	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1065	  This fault occurs under a specific hardware condition when a
1066	  load/store instruction performs an address translation using:
1067	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1068	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1069	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1070	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1071
1072	  The workaround is to ensure these bits are clear in TCR_ELx.
1073	  The workaround only affects the Fujitsu-A64FX.
1074
1075	  If unsure, say Y.
1076
1077config HISILICON_ERRATUM_161600802
1078	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1079	default y
1080	help
1081	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1082	  when issued ITS commands such as VMOVP and VMAPP, and requires
1083	  a 128kB offset to be applied to the target address in this commands.
1084
1085	  If unsure, say Y.
1086
1087config QCOM_FALKOR_ERRATUM_1003
1088	bool "Falkor E1003: Incorrect translation due to ASID change"
1089	default y
1090	help
1091	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1092	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1093	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1094	  then only for entries in the walk cache, since the leaf translation
1095	  is unchanged. Work around the erratum by invalidating the walk cache
1096	  entries for the trampoline before entering the kernel proper.
1097
1098config QCOM_FALKOR_ERRATUM_1009
1099	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1100	default y
1101	select ARM64_WORKAROUND_REPEAT_TLBI
1102	help
1103	  On Falkor v1, the CPU may prematurely complete a DSB following a
1104	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1105	  one more time to fix the issue.
1106
1107	  If unsure, say Y.
1108
1109config QCOM_QDF2400_ERRATUM_0065
1110	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1111	default y
1112	help
1113	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1114	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1115	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1116
1117	  If unsure, say Y.
1118
1119config QCOM_FALKOR_ERRATUM_E1041
1120	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1121	default y
1122	help
1123	  Falkor CPU may speculatively fetch instructions from an improper
1124	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1125	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1126
1127	  If unsure, say Y.
1128
1129config NVIDIA_CARMEL_CNP_ERRATUM
1130	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1131	default y
1132	help
1133	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1134	  invalidate shared TLB entries installed by a different core, as it would
1135	  on standard ARM cores.
1136
1137	  If unsure, say Y.
1138
1139config SOCIONEXT_SYNQUACER_PREITS
1140	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1141	default y
1142	help
1143	  Socionext Synquacer SoCs implement a separate h/w block to generate
1144	  MSI doorbell writes with non-zero values for the device ID.
1145
1146	  If unsure, say Y.
1147
1148endmenu # "ARM errata workarounds via the alternatives framework"
1149
1150choice
1151	prompt "Page size"
1152	default ARM64_4K_PAGES
1153	help
1154	  Page size (translation granule) configuration.
1155
1156config ARM64_4K_PAGES
1157	bool "4KB"
1158	help
1159	  This feature enables 4KB pages support.
1160
1161config ARM64_16K_PAGES
1162	bool "16KB"
1163	help
1164	  The system will use 16KB pages support. AArch32 emulation
1165	  requires applications compiled with 16K (or a multiple of 16K)
1166	  aligned segments.
1167
1168config ARM64_64K_PAGES
1169	bool "64KB"
1170	help
1171	  This feature enables 64KB pages support (4KB by default)
1172	  allowing only two levels of page tables and faster TLB
1173	  look-up. AArch32 emulation requires applications compiled
1174	  with 64K aligned segments.
1175
1176endchoice
1177
1178choice
1179	prompt "Virtual address space size"
1180	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
1181	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
1182	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
1183	help
1184	  Allows choosing one of multiple possible virtual address
1185	  space sizes. The level of translation table is determined by
1186	  a combination of page size and virtual address space size.
1187
1188config ARM64_VA_BITS_36
1189	bool "36-bit" if EXPERT
1190	depends on ARM64_16K_PAGES
1191
1192config ARM64_VA_BITS_39
1193	bool "39-bit"
1194	depends on ARM64_4K_PAGES
1195
1196config ARM64_VA_BITS_42
1197	bool "42-bit"
1198	depends on ARM64_64K_PAGES
1199
1200config ARM64_VA_BITS_47
1201	bool "47-bit"
1202	depends on ARM64_16K_PAGES
1203
1204config ARM64_VA_BITS_48
1205	bool "48-bit"
1206
1207config ARM64_VA_BITS_52
1208	bool "52-bit"
1209	depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
1210	help
1211	  Enable 52-bit virtual addressing for userspace when explicitly
1212	  requested via a hint to mmap(). The kernel will also use 52-bit
1213	  virtual addresses for its own mappings (provided HW support for
1214	  this feature is available, otherwise it reverts to 48-bit).
1215
1216	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1217	  ARMv8.3 Pointer Authentication will result in the PAC being
1218	  reduced from 7 bits to 3 bits, which may have a significant
1219	  impact on its susceptibility to brute-force attacks.
1220
1221	  If unsure, select 48-bit virtual addressing instead.
1222
1223endchoice
1224
1225config ARM64_FORCE_52BIT
1226	bool "Force 52-bit virtual addresses for userspace"
1227	depends on ARM64_VA_BITS_52 && EXPERT
1228	help
1229	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1230	  to maintain compatibility with older software by providing 48-bit VAs
1231	  unless a hint is supplied to mmap.
1232
1233	  This configuration option disables the 48-bit compatibility logic, and
1234	  forces all userspace addresses to be 52-bit on HW that supports it. One
1235	  should only enable this configuration option for stress testing userspace
1236	  memory management code. If unsure say N here.
1237
1238config ARM64_VA_BITS
1239	int
1240	default 36 if ARM64_VA_BITS_36
1241	default 39 if ARM64_VA_BITS_39
1242	default 42 if ARM64_VA_BITS_42
1243	default 47 if ARM64_VA_BITS_47
1244	default 48 if ARM64_VA_BITS_48
1245	default 52 if ARM64_VA_BITS_52
1246
1247choice
1248	prompt "Physical address space size"
1249	default ARM64_PA_BITS_48
1250	help
1251	  Choose the maximum physical address range that the kernel will
1252	  support.
1253
1254config ARM64_PA_BITS_48
1255	bool "48-bit"
1256
1257config ARM64_PA_BITS_52
1258	bool "52-bit (ARMv8.2)"
1259	depends on ARM64_64K_PAGES
1260	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1261	help
1262	  Enable support for a 52-bit physical address space, introduced as
1263	  part of the ARMv8.2-LPA extension.
1264
1265	  With this enabled, the kernel will also continue to work on CPUs that
1266	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1267	  minor performance overhead).
1268
1269endchoice
1270
1271config ARM64_PA_BITS
1272	int
1273	default 48 if ARM64_PA_BITS_48
1274	default 52 if ARM64_PA_BITS_52
1275
1276choice
1277	prompt "Endianness"
1278	default CPU_LITTLE_ENDIAN
1279	help
1280	  Select the endianness of data accesses performed by the CPU. Userspace
1281	  applications will need to be compiled and linked for the endianness
1282	  that is selected here.
1283
1284config CPU_BIG_ENDIAN
1285	bool "Build big-endian kernel"
1286	depends on !LD_IS_LLD || LLD_VERSION >= 130000
1287	help
1288	  Say Y if you plan on running a kernel with a big-endian userspace.
1289
1290config CPU_LITTLE_ENDIAN
1291	bool "Build little-endian kernel"
1292	help
1293	  Say Y if you plan on running a kernel with a little-endian userspace.
1294	  This is usually the case for distributions targeting arm64.
1295
1296endchoice
1297
1298config SCHED_MC
1299	bool "Multi-core scheduler support"
1300	help
1301	  Multi-core scheduler support improves the CPU scheduler's decision
1302	  making when dealing with multi-core CPU chips at a cost of slightly
1303	  increased overhead in some places. If unsure say N here.
1304
1305config SCHED_CLUSTER
1306	bool "Cluster scheduler support"
1307	help
1308	  Cluster scheduler support improves the CPU scheduler's decision
1309	  making when dealing with machines that have clusters of CPUs.
1310	  Cluster usually means a couple of CPUs which are placed closely
1311	  by sharing mid-level caches, last-level cache tags or internal
1312	  busses.
1313
1314config SCHED_SMT
1315	bool "SMT scheduler support"
1316	help
1317	  Improves the CPU scheduler's decision making when dealing with
1318	  MultiThreading at a cost of slightly increased overhead in some
1319	  places. If unsure say N here.
1320
1321config NR_CPUS
1322	int "Maximum number of CPUs (2-4096)"
1323	range 2 4096
1324	default "256"
1325
1326config HOTPLUG_CPU
1327	bool "Support for hot-pluggable CPUs"
1328	select GENERIC_IRQ_MIGRATION
1329	help
1330	  Say Y here to experiment with turning CPUs off and on.  CPUs
1331	  can be controlled through /sys/devices/system/cpu.
1332
1333# Common NUMA Features
1334config NUMA
1335	bool "NUMA Memory Allocation and Scheduler Support"
1336	select GENERIC_ARCH_NUMA
1337	select ACPI_NUMA if ACPI
1338	select OF_NUMA
1339	select HAVE_SETUP_PER_CPU_AREA
1340	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1341	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1342	select USE_PERCPU_NUMA_NODE_ID
1343	help
1344	  Enable NUMA (Non-Uniform Memory Access) support.
1345
1346	  The kernel will try to allocate memory used by a CPU on the
1347	  local memory of the CPU and add some more
1348	  NUMA awareness to the kernel.
1349
1350config NODES_SHIFT
1351	int "Maximum NUMA Nodes (as a power of 2)"
1352	range 1 10
1353	default "4"
1354	depends on NUMA
1355	help
1356	  Specify the maximum number of NUMA Nodes available on the target
1357	  system.  Increases memory reserved to accommodate various tables.
1358
1359source "kernel/Kconfig.hz"
1360
1361config ARCH_SPARSEMEM_ENABLE
1362	def_bool y
1363	select SPARSEMEM_VMEMMAP_ENABLE
1364	select SPARSEMEM_VMEMMAP
1365
1366config HW_PERF_EVENTS
1367	def_bool y
1368	depends on ARM_PMU
1369
1370# Supported by clang >= 7.0 or GCC >= 12.0.0
1371config CC_HAVE_SHADOW_CALL_STACK
1372	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1373
1374config PARAVIRT
1375	bool "Enable paravirtualization code"
1376	help
1377	  This changes the kernel so it can modify itself when it is run
1378	  under a hypervisor, potentially improving performance significantly
1379	  over full virtualization.
1380
1381config PARAVIRT_TIME_ACCOUNTING
1382	bool "Paravirtual steal time accounting"
1383	select PARAVIRT
1384	help
1385	  Select this option to enable fine granularity task steal time
1386	  accounting. Time spent executing other tasks in parallel with
1387	  the current vCPU is discounted from the vCPU power. To account for
1388	  that, there can be a small performance impact.
1389
1390	  If in doubt, say N here.
1391
1392config KEXEC
1393	depends on PM_SLEEP_SMP
1394	select KEXEC_CORE
1395	bool "kexec system call"
1396	help
1397	  kexec is a system call that implements the ability to shutdown your
1398	  current kernel, and to start another kernel.  It is like a reboot
1399	  but it is independent of the system firmware.   And like a reboot
1400	  you can start any kernel with it, not just Linux.
1401
1402config KEXEC_FILE
1403	bool "kexec file based system call"
1404	select KEXEC_CORE
1405	select HAVE_IMA_KEXEC if IMA
1406	help
1407	  This is new version of kexec system call. This system call is
1408	  file based and takes file descriptors as system call argument
1409	  for kernel and initramfs as opposed to list of segments as
1410	  accepted by previous system call.
1411
1412config KEXEC_SIG
1413	bool "Verify kernel signature during kexec_file_load() syscall"
1414	depends on KEXEC_FILE
1415	help
1416	  Select this option to verify a signature with loaded kernel
1417	  image. If configured, any attempt of loading a image without
1418	  valid signature will fail.
1419
1420	  In addition to that option, you need to enable signature
1421	  verification for the corresponding kernel image type being
1422	  loaded in order for this to work.
1423
1424config KEXEC_IMAGE_VERIFY_SIG
1425	bool "Enable Image signature verification support"
1426	default y
1427	depends on KEXEC_SIG
1428	depends on EFI && SIGNED_PE_FILE_VERIFICATION
1429	help
1430	  Enable Image signature verification support.
1431
1432comment "Support for PE file signature verification disabled"
1433	depends on KEXEC_SIG
1434	depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
1435
1436config CRASH_DUMP
1437	bool "Build kdump crash kernel"
1438	help
1439	  Generate crash dump after being started by kexec. This should
1440	  be normally only set in special crash dump kernels which are
1441	  loaded in the main kernel with kexec-tools into a specially
1442	  reserved region and then later executed after a crash by
1443	  kdump/kexec.
1444
1445	  For more details see Documentation/admin-guide/kdump/kdump.rst
1446
1447config TRANS_TABLE
1448	def_bool y
1449	depends on HIBERNATION || KEXEC_CORE
1450
1451config XEN_DOM0
1452	def_bool y
1453	depends on XEN
1454
1455config XEN
1456	bool "Xen guest support on ARM64"
1457	depends on ARM64 && OF
1458	select SWIOTLB_XEN
1459	select PARAVIRT
1460	help
1461	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1462
1463# include/linux/mmzone.h requires the following to be true:
1464#
1465#   MAX_ORDER - 1 + PAGE_SHIFT <= SECTION_SIZE_BITS
1466#
1467# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS + 1 - PAGE_SHIFT:
1468#
1469#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_ORDER  |  default MAX_ORDER |
1470# ----+-------------------+--------------+-----------------+--------------------+
1471# 4K  |       27          |      12      |       16        |         11         |
1472# 16K |       27          |      14      |       14        |         12         |
1473# 64K |       29          |      16      |       14        |         14         |
1474config ARCH_FORCE_MAX_ORDER
1475	int "Maximum zone order" if ARM64_4K_PAGES || ARM64_16K_PAGES
1476	default "14" if ARM64_64K_PAGES
1477	range 12 14 if ARM64_16K_PAGES
1478	default "12" if ARM64_16K_PAGES
1479	range 11 16 if ARM64_4K_PAGES
1480	default "11"
1481	help
1482	  The kernel memory allocator divides physically contiguous memory
1483	  blocks into "zones", where each zone is a power of two number of
1484	  pages.  This option selects the largest power of two that the kernel
1485	  keeps in the memory allocator.  If you need to allocate very large
1486	  blocks of physically contiguous memory, then you may need to
1487	  increase this value.
1488
1489	  This config option is actually maximum order plus one. For example,
1490	  a value of 11 means that the largest free memory block is 2^10 pages.
1491
1492	  We make sure that we can allocate up to a HugePage size for each configuration.
1493	  Hence we have :
1494		MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
1495
1496	  However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
1497	  4M allocations matching the default size used by generic code.
1498
1499config UNMAP_KERNEL_AT_EL0
1500	bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
1501	default y
1502	help
1503	  Speculation attacks against some high-performance processors can
1504	  be used to bypass MMU permission checks and leak kernel data to
1505	  userspace. This can be defended against by unmapping the kernel
1506	  when running in userspace, mapping it back in on exception entry
1507	  via a trampoline page in the vector table.
1508
1509	  If unsure, say Y.
1510
1511config MITIGATE_SPECTRE_BRANCH_HISTORY
1512	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1513	default y
1514	help
1515	  Speculation attacks against some high-performance processors can
1516	  make use of branch history to influence future speculation.
1517	  When taking an exception from user-space, a sequence of branches
1518	  or a firmware call overwrites the branch history.
1519
1520config RODATA_FULL_DEFAULT_ENABLED
1521	bool "Apply r/o permissions of VM areas also to their linear aliases"
1522	default y
1523	help
1524	  Apply read-only attributes of VM areas to the linear alias of
1525	  the backing pages as well. This prevents code or read-only data
1526	  from being modified (inadvertently or intentionally) via another
1527	  mapping of the same memory page. This additional enhancement can
1528	  be turned off at runtime by passing rodata=[off|on] (and turned on
1529	  with rodata=full if this option is set to 'n')
1530
1531	  This requires the linear region to be mapped down to pages,
1532	  which may adversely affect performance in some cases.
1533
1534config ARM64_SW_TTBR0_PAN
1535	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1536	help
1537	  Enabling this option prevents the kernel from accessing
1538	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1539	  zeroed area and reserved ASID. The user access routines
1540	  restore the valid TTBR0_EL1 temporarily.
1541
1542config ARM64_TAGGED_ADDR_ABI
1543	bool "Enable the tagged user addresses syscall ABI"
1544	default y
1545	help
1546	  When this option is enabled, user applications can opt in to a
1547	  relaxed ABI via prctl() allowing tagged addresses to be passed
1548	  to system calls as pointer arguments. For details, see
1549	  Documentation/arm64/tagged-address-abi.rst.
1550
1551menuconfig COMPAT
1552	bool "Kernel support for 32-bit EL0"
1553	depends on ARM64_4K_PAGES || EXPERT
1554	select HAVE_UID16
1555	select OLD_SIGSUSPEND3
1556	select COMPAT_OLD_SIGACTION
1557	help
1558	  This option enables support for a 32-bit EL0 running under a 64-bit
1559	  kernel at EL1. AArch32-specific components such as system calls,
1560	  the user helper functions, VFP support and the ptrace interface are
1561	  handled appropriately by the kernel.
1562
1563	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1564	  that you will only be able to execute AArch32 binaries that were compiled
1565	  with page size aligned segments.
1566
1567	  If you want to execute 32-bit userspace applications, say Y.
1568
1569if COMPAT
1570
1571config KUSER_HELPERS
1572	bool "Enable kuser helpers page for 32-bit applications"
1573	default y
1574	help
1575	  Warning: disabling this option may break 32-bit user programs.
1576
1577	  Provide kuser helpers to compat tasks. The kernel provides
1578	  helper code to userspace in read only form at a fixed location
1579	  to allow userspace to be independent of the CPU type fitted to
1580	  the system. This permits binaries to be run on ARMv4 through
1581	  to ARMv8 without modification.
1582
1583	  See Documentation/arm/kernel_user_helpers.rst for details.
1584
1585	  However, the fixed address nature of these helpers can be used
1586	  by ROP (return orientated programming) authors when creating
1587	  exploits.
1588
1589	  If all of the binaries and libraries which run on your platform
1590	  are built specifically for your platform, and make no use of
1591	  these helpers, then you can turn this option off to hinder
1592	  such exploits. However, in that case, if a binary or library
1593	  relying on those helpers is run, it will not function correctly.
1594
1595	  Say N here only if you are absolutely certain that you do not
1596	  need these helpers; otherwise, the safe option is to say Y.
1597
1598config COMPAT_VDSO
1599	bool "Enable vDSO for 32-bit applications"
1600	depends on !CPU_BIG_ENDIAN
1601	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1602	select GENERIC_COMPAT_VDSO
1603	default y
1604	help
1605	  Place in the process address space of 32-bit applications an
1606	  ELF shared object providing fast implementations of gettimeofday
1607	  and clock_gettime.
1608
1609	  You must have a 32-bit build of glibc 2.22 or later for programs
1610	  to seamlessly take advantage of this.
1611
1612config THUMB2_COMPAT_VDSO
1613	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1614	depends on COMPAT_VDSO
1615	default y
1616	help
1617	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1618	  otherwise with '-marm'.
1619
1620config COMPAT_ALIGNMENT_FIXUPS
1621	bool "Fix up misaligned multi-word loads and stores in user space"
1622
1623menuconfig ARMV8_DEPRECATED
1624	bool "Emulate deprecated/obsolete ARMv8 instructions"
1625	depends on SYSCTL
1626	help
1627	  Legacy software support may require certain instructions
1628	  that have been deprecated or obsoleted in the architecture.
1629
1630	  Enable this config to enable selective emulation of these
1631	  features.
1632
1633	  If unsure, say Y
1634
1635if ARMV8_DEPRECATED
1636
1637config SWP_EMULATION
1638	bool "Emulate SWP/SWPB instructions"
1639	help
1640	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1641	  they are always undefined. Say Y here to enable software
1642	  emulation of these instructions for userspace using LDXR/STXR.
1643	  This feature can be controlled at runtime with the abi.swp
1644	  sysctl which is disabled by default.
1645
1646	  In some older versions of glibc [<=2.8] SWP is used during futex
1647	  trylock() operations with the assumption that the code will not
1648	  be preempted. This invalid assumption may be more likely to fail
1649	  with SWP emulation enabled, leading to deadlock of the user
1650	  application.
1651
1652	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1653	  on an external transaction monitoring block called a global
1654	  monitor to maintain update atomicity. If your system does not
1655	  implement a global monitor, this option can cause programs that
1656	  perform SWP operations to uncached memory to deadlock.
1657
1658	  If unsure, say Y
1659
1660config CP15_BARRIER_EMULATION
1661	bool "Emulate CP15 Barrier instructions"
1662	help
1663	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1664	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1665	  strongly recommended to use the ISB, DSB, and DMB
1666	  instructions instead.
1667
1668	  Say Y here to enable software emulation of these
1669	  instructions for AArch32 userspace code. When this option is
1670	  enabled, CP15 barrier usage is traced which can help
1671	  identify software that needs updating. This feature can be
1672	  controlled at runtime with the abi.cp15_barrier sysctl.
1673
1674	  If unsure, say Y
1675
1676config SETEND_EMULATION
1677	bool "Emulate SETEND instruction"
1678	help
1679	  The SETEND instruction alters the data-endianness of the
1680	  AArch32 EL0, and is deprecated in ARMv8.
1681
1682	  Say Y here to enable software emulation of the instruction
1683	  for AArch32 userspace code. This feature can be controlled
1684	  at runtime with the abi.setend sysctl.
1685
1686	  Note: All the cpus on the system must have mixed endian support at EL0
1687	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1688	  endian - is hotplugged in after this feature has been enabled, there could
1689	  be unexpected results in the applications.
1690
1691	  If unsure, say Y
1692endif # ARMV8_DEPRECATED
1693
1694endif # COMPAT
1695
1696menu "ARMv8.1 architectural features"
1697
1698config ARM64_HW_AFDBM
1699	bool "Support for hardware updates of the Access and Dirty page flags"
1700	default y
1701	help
1702	  The ARMv8.1 architecture extensions introduce support for
1703	  hardware updates of the access and dirty information in page
1704	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1705	  capable processors, accesses to pages with PTE_AF cleared will
1706	  set this bit instead of raising an access flag fault.
1707	  Similarly, writes to read-only pages with the DBM bit set will
1708	  clear the read-only bit (AP[2]) instead of raising a
1709	  permission fault.
1710
1711	  Kernels built with this configuration option enabled continue
1712	  to work on pre-ARMv8.1 hardware and the performance impact is
1713	  minimal. If unsure, say Y.
1714
1715config ARM64_PAN
1716	bool "Enable support for Privileged Access Never (PAN)"
1717	default y
1718	help
1719	  Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1720	  prevents the kernel or hypervisor from accessing user-space (EL0)
1721	  memory directly.
1722
1723	  Choosing this option will cause any unprotected (not using
1724	  copy_to_user et al) memory access to fail with a permission fault.
1725
1726	  The feature is detected at runtime, and will remain as a 'nop'
1727	  instruction if the cpu does not implement the feature.
1728
1729config AS_HAS_LDAPR
1730	def_bool $(as-instr,.arch_extension rcpc)
1731
1732config AS_HAS_LSE_ATOMICS
1733	def_bool $(as-instr,.arch_extension lse)
1734
1735config ARM64_LSE_ATOMICS
1736	bool
1737	default ARM64_USE_LSE_ATOMICS
1738	depends on AS_HAS_LSE_ATOMICS
1739
1740config ARM64_USE_LSE_ATOMICS
1741	bool "Atomic instructions"
1742	default y
1743	help
1744	  As part of the Large System Extensions, ARMv8.1 introduces new
1745	  atomic instructions that are designed specifically to scale in
1746	  very large systems.
1747
1748	  Say Y here to make use of these instructions for the in-kernel
1749	  atomic routines. This incurs a small overhead on CPUs that do
1750	  not support these instructions and requires the kernel to be
1751	  built with binutils >= 2.25 in order for the new instructions
1752	  to be used.
1753
1754endmenu # "ARMv8.1 architectural features"
1755
1756menu "ARMv8.2 architectural features"
1757
1758config AS_HAS_ARMV8_2
1759	def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a)
1760
1761config AS_HAS_SHA3
1762	def_bool $(as-instr,.arch armv8.2-a+sha3)
1763
1764config ARM64_PMEM
1765	bool "Enable support for persistent memory"
1766	select ARCH_HAS_PMEM_API
1767	select ARCH_HAS_UACCESS_FLUSHCACHE
1768	help
1769	  Say Y to enable support for the persistent memory API based on the
1770	  ARMv8.2 DCPoP feature.
1771
1772	  The feature is detected at runtime, and the kernel will use DC CVAC
1773	  operations if DC CVAP is not supported (following the behaviour of
1774	  DC CVAP itself if the system does not define a point of persistence).
1775
1776config ARM64_RAS_EXTN
1777	bool "Enable support for RAS CPU Extensions"
1778	default y
1779	help
1780	  CPUs that support the Reliability, Availability and Serviceability
1781	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1782	  errors, classify them and report them to software.
1783
1784	  On CPUs with these extensions system software can use additional
1785	  barriers to determine if faults are pending and read the
1786	  classification from a new set of registers.
1787
1788	  Selecting this feature will allow the kernel to use these barriers
1789	  and access the new registers if the system supports the extension.
1790	  Platform RAS features may additionally depend on firmware support.
1791
1792config ARM64_CNP
1793	bool "Enable support for Common Not Private (CNP) translations"
1794	default y
1795	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1796	help
1797	  Common Not Private (CNP) allows translation table entries to
1798	  be shared between different PEs in the same inner shareable
1799	  domain, so the hardware can use this fact to optimise the
1800	  caching of such entries in the TLB.
1801
1802	  Selecting this option allows the CNP feature to be detected
1803	  at runtime, and does not affect PEs that do not implement
1804	  this feature.
1805
1806endmenu # "ARMv8.2 architectural features"
1807
1808menu "ARMv8.3 architectural features"
1809
1810config ARM64_PTR_AUTH
1811	bool "Enable support for pointer authentication"
1812	default y
1813	help
1814	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1815	  instructions for signing and authenticating pointers against secret
1816	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1817	  and other attacks.
1818
1819	  This option enables these instructions at EL0 (i.e. for userspace).
1820	  Choosing this option will cause the kernel to initialise secret keys
1821	  for each process at exec() time, with these keys being
1822	  context-switched along with the process.
1823
1824	  The feature is detected at runtime. If the feature is not present in
1825	  hardware it will not be advertised to userspace/KVM guest nor will it
1826	  be enabled.
1827
1828	  If the feature is present on the boot CPU but not on a late CPU, then
1829	  the late CPU will be parked. Also, if the boot CPU does not have
1830	  address auth and the late CPU has then the late CPU will still boot
1831	  but with the feature disabled. On such a system, this option should
1832	  not be selected.
1833
1834config ARM64_PTR_AUTH_KERNEL
1835	bool "Use pointer authentication for kernel"
1836	default y
1837	depends on ARM64_PTR_AUTH
1838	depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_ARMV8_3
1839	# Modern compilers insert a .note.gnu.property section note for PAC
1840	# which is only understood by binutils starting with version 2.33.1.
1841	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1842	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1843	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1844	help
1845	  If the compiler supports the -mbranch-protection or
1846	  -msign-return-address flag (e.g. GCC 7 or later), then this option
1847	  will cause the kernel itself to be compiled with return address
1848	  protection. In this case, and if the target hardware is known to
1849	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
1850	  disabled with minimal loss of protection.
1851
1852	  This feature works with FUNCTION_GRAPH_TRACER option only if
1853	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
1854
1855config CC_HAS_BRANCH_PROT_PAC_RET
1856	# GCC 9 or later, clang 8 or later
1857	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1858
1859config CC_HAS_SIGN_RETURN_ADDRESS
1860	# GCC 7, 8
1861	def_bool $(cc-option,-msign-return-address=all)
1862
1863config AS_HAS_ARMV8_3
1864	def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
1865
1866config AS_HAS_CFI_NEGATE_RA_STATE
1867	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1868
1869endmenu # "ARMv8.3 architectural features"
1870
1871menu "ARMv8.4 architectural features"
1872
1873config ARM64_AMU_EXTN
1874	bool "Enable support for the Activity Monitors Unit CPU extension"
1875	default y
1876	help
1877	  The activity monitors extension is an optional extension introduced
1878	  by the ARMv8.4 CPU architecture. This enables support for version 1
1879	  of the activity monitors architecture, AMUv1.
1880
1881	  To enable the use of this extension on CPUs that implement it, say Y.
1882
1883	  Note that for architectural reasons, firmware _must_ implement AMU
1884	  support when running on CPUs that present the activity monitors
1885	  extension. The required support is present in:
1886	    * Version 1.5 and later of the ARM Trusted Firmware
1887
1888	  For kernels that have this configuration enabled but boot with broken
1889	  firmware, you may need to say N here until the firmware is fixed.
1890	  Otherwise you may experience firmware panics or lockups when
1891	  accessing the counter registers. Even if you are not observing these
1892	  symptoms, the values returned by the register reads might not
1893	  correctly reflect reality. Most commonly, the value read will be 0,
1894	  indicating that the counter is not enabled.
1895
1896config AS_HAS_ARMV8_4
1897	def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
1898
1899config ARM64_TLB_RANGE
1900	bool "Enable support for tlbi range feature"
1901	default y
1902	depends on AS_HAS_ARMV8_4
1903	help
1904	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
1905	  range of input addresses.
1906
1907	  The feature introduces new assembly instructions, and they were
1908	  support when binutils >= 2.30.
1909
1910endmenu # "ARMv8.4 architectural features"
1911
1912menu "ARMv8.5 architectural features"
1913
1914config AS_HAS_ARMV8_5
1915	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
1916
1917config ARM64_BTI
1918	bool "Branch Target Identification support"
1919	default y
1920	help
1921	  Branch Target Identification (part of the ARMv8.5 Extensions)
1922	  provides a mechanism to limit the set of locations to which computed
1923	  branch instructions such as BR or BLR can jump.
1924
1925	  To make use of BTI on CPUs that support it, say Y.
1926
1927	  BTI is intended to provide complementary protection to other control
1928	  flow integrity protection mechanisms, such as the Pointer
1929	  authentication mechanism provided as part of the ARMv8.3 Extensions.
1930	  For this reason, it does not make sense to enable this option without
1931	  also enabling support for pointer authentication.  Thus, when
1932	  enabling this option you should also select ARM64_PTR_AUTH=y.
1933
1934	  Userspace binaries must also be specifically compiled to make use of
1935	  this mechanism.  If you say N here or the hardware does not support
1936	  BTI, such binaries can still run, but you get no additional
1937	  enforcement of branch destinations.
1938
1939config ARM64_BTI_KERNEL
1940	bool "Use Branch Target Identification for kernel"
1941	default y
1942	depends on ARM64_BTI
1943	depends on ARM64_PTR_AUTH_KERNEL
1944	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
1945	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
1946	depends on !CC_IS_GCC || GCC_VERSION >= 100100
1947	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
1948	depends on !CC_IS_GCC
1949	# https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9
1950	depends on !CC_IS_CLANG || CLANG_VERSION >= 120000
1951	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1952	help
1953	  Build the kernel with Branch Target Identification annotations
1954	  and enable enforcement of this for kernel code. When this option
1955	  is enabled and the system supports BTI all kernel code including
1956	  modular code must have BTI enabled.
1957
1958config CC_HAS_BRANCH_PROT_PAC_RET_BTI
1959	# GCC 9 or later, clang 8 or later
1960	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
1961
1962config ARM64_E0PD
1963	bool "Enable support for E0PD"
1964	default y
1965	help
1966	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
1967	  that EL0 accesses made via TTBR1 always fault in constant time,
1968	  providing similar benefits to KASLR as those provided by KPTI, but
1969	  with lower overhead and without disrupting legitimate access to
1970	  kernel memory such as SPE.
1971
1972	  This option enables E0PD for TTBR1 where available.
1973
1974config ARM64_AS_HAS_MTE
1975	# Initial support for MTE went in binutils 2.32.0, checked with
1976	# ".arch armv8.5-a+memtag" below. However, this was incomplete
1977	# as a late addition to the final architecture spec (LDGM/STGM)
1978	# is only supported in the newer 2.32.x and 2.33 binutils
1979	# versions, hence the extra "stgm" instruction check below.
1980	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
1981
1982config ARM64_MTE
1983	bool "Memory Tagging Extension support"
1984	default y
1985	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
1986	depends on AS_HAS_ARMV8_5
1987	depends on AS_HAS_LSE_ATOMICS
1988	# Required for tag checking in the uaccess routines
1989	depends on ARM64_PAN
1990	select ARCH_HAS_SUBPAGE_FAULTS
1991	select ARCH_USES_HIGH_VMA_FLAGS
1992	select ARCH_USES_PG_ARCH_X
1993	help
1994	  Memory Tagging (part of the ARMv8.5 Extensions) provides
1995	  architectural support for run-time, always-on detection of
1996	  various classes of memory error to aid with software debugging
1997	  to eliminate vulnerabilities arising from memory-unsafe
1998	  languages.
1999
2000	  This option enables the support for the Memory Tagging
2001	  Extension at EL0 (i.e. for userspace).
2002
2003	  Selecting this option allows the feature to be detected at
2004	  runtime. Any secondary CPU not implementing this feature will
2005	  not be allowed a late bring-up.
2006
2007	  Userspace binaries that want to use this feature must
2008	  explicitly opt in. The mechanism for the userspace is
2009	  described in:
2010
2011	  Documentation/arm64/memory-tagging-extension.rst.
2012
2013endmenu # "ARMv8.5 architectural features"
2014
2015menu "ARMv8.7 architectural features"
2016
2017config ARM64_EPAN
2018	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2019	default y
2020	depends on ARM64_PAN
2021	help
2022	  Enhanced Privileged Access Never (EPAN) allows Privileged
2023	  Access Never to be used with Execute-only mappings.
2024
2025	  The feature is detected at runtime, and will remain disabled
2026	  if the cpu does not implement the feature.
2027endmenu # "ARMv8.7 architectural features"
2028
2029config ARM64_SVE
2030	bool "ARM Scalable Vector Extension support"
2031	default y
2032	help
2033	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2034	  execution state which complements and extends the SIMD functionality
2035	  of the base architecture to support much larger vectors and to enable
2036	  additional vectorisation opportunities.
2037
2038	  To enable use of this extension on CPUs that implement it, say Y.
2039
2040	  On CPUs that support the SVE2 extensions, this option will enable
2041	  those too.
2042
2043	  Note that for architectural reasons, firmware _must_ implement SVE
2044	  support when running on SVE capable hardware.  The required support
2045	  is present in:
2046
2047	    * version 1.5 and later of the ARM Trusted Firmware
2048	    * the AArch64 boot wrapper since commit 5e1261e08abf
2049	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2050
2051	  For other firmware implementations, consult the firmware documentation
2052	  or vendor.
2053
2054	  If you need the kernel to boot on SVE-capable hardware with broken
2055	  firmware, you may need to say N here until you get your firmware
2056	  fixed.  Otherwise, you may experience firmware panics or lockups when
2057	  booting the kernel.  If unsure and you are not observing these
2058	  symptoms, you should assume that it is safe to say Y.
2059
2060config ARM64_SME
2061	bool "ARM Scalable Matrix Extension support"
2062	default y
2063	depends on ARM64_SVE
2064	help
2065	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2066	  execution state which utilises a substantial subset of the SVE
2067	  instruction set, together with the addition of new architectural
2068	  register state capable of holding two dimensional matrix tiles to
2069	  enable various matrix operations.
2070
2071config ARM64_MODULE_PLTS
2072	bool "Use PLTs to allow module memory to spill over into vmalloc area"
2073	depends on MODULES
2074	select HAVE_MOD_ARCH_SPECIFIC
2075	help
2076	  Allocate PLTs when loading modules so that jumps and calls whose
2077	  targets are too far away for their relative offsets to be encoded
2078	  in the instructions themselves can be bounced via veneers in the
2079	  module's PLT. This allows modules to be allocated in the generic
2080	  vmalloc area after the dedicated module memory area has been
2081	  exhausted.
2082
2083	  When running with address space randomization (KASLR), the module
2084	  region itself may be too far away for ordinary relative jumps and
2085	  calls, and so in that case, module PLTs are required and cannot be
2086	  disabled.
2087
2088	  Specific errata workaround(s) might also force module PLTs to be
2089	  enabled (ARM64_ERRATUM_843419).
2090
2091config ARM64_PSEUDO_NMI
2092	bool "Support for NMI-like interrupts"
2093	select ARM_GIC_V3
2094	help
2095	  Adds support for mimicking Non-Maskable Interrupts through the use of
2096	  GIC interrupt priority. This support requires version 3 or later of
2097	  ARM GIC.
2098
2099	  This high priority configuration for interrupts needs to be
2100	  explicitly enabled by setting the kernel parameter
2101	  "irqchip.gicv3_pseudo_nmi" to 1.
2102
2103	  If unsure, say N
2104
2105if ARM64_PSEUDO_NMI
2106config ARM64_DEBUG_PRIORITY_MASKING
2107	bool "Debug interrupt priority masking"
2108	help
2109	  This adds runtime checks to functions enabling/disabling
2110	  interrupts when using priority masking. The additional checks verify
2111	  the validity of ICC_PMR_EL1 when calling concerned functions.
2112
2113	  If unsure, say N
2114endif # ARM64_PSEUDO_NMI
2115
2116config RELOCATABLE
2117	bool "Build a relocatable kernel image" if EXPERT
2118	select ARCH_HAS_RELR
2119	default y
2120	help
2121	  This builds the kernel as a Position Independent Executable (PIE),
2122	  which retains all relocation metadata required to relocate the
2123	  kernel binary at runtime to a different virtual address than the
2124	  address it was linked at.
2125	  Since AArch64 uses the RELA relocation format, this requires a
2126	  relocation pass at runtime even if the kernel is loaded at the
2127	  same address it was linked at.
2128
2129config RANDOMIZE_BASE
2130	bool "Randomize the address of the kernel image"
2131	select ARM64_MODULE_PLTS if MODULES
2132	select RELOCATABLE
2133	help
2134	  Randomizes the virtual address at which the kernel image is
2135	  loaded, as a security feature that deters exploit attempts
2136	  relying on knowledge of the location of kernel internals.
2137
2138	  It is the bootloader's job to provide entropy, by passing a
2139	  random u64 value in /chosen/kaslr-seed at kernel entry.
2140
2141	  When booting via the UEFI stub, it will invoke the firmware's
2142	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2143	  to the kernel proper. In addition, it will randomise the physical
2144	  location of the kernel Image as well.
2145
2146	  If unsure, say N.
2147
2148config RANDOMIZE_MODULE_REGION_FULL
2149	bool "Randomize the module region over a 2 GB range"
2150	depends on RANDOMIZE_BASE
2151	default y
2152	help
2153	  Randomizes the location of the module region inside a 2 GB window
2154	  covering the core kernel. This way, it is less likely for modules
2155	  to leak information about the location of core kernel data structures
2156	  but it does imply that function calls between modules and the core
2157	  kernel will need to be resolved via veneers in the module PLT.
2158
2159	  When this option is not set, the module region will be randomized over
2160	  a limited range that contains the [_stext, _etext] interval of the
2161	  core kernel, so branch relocations are almost always in range unless
2162	  ARM64_MODULE_PLTS is enabled and the region is exhausted. In this
2163	  particular case of region exhaustion, modules might be able to fall
2164	  back to a larger 2GB area.
2165
2166config CC_HAVE_STACKPROTECTOR_SYSREG
2167	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2168
2169config STACKPROTECTOR_PER_TASK
2170	def_bool y
2171	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2172
2173config UNWIND_PATCH_PAC_INTO_SCS
2174	bool "Enable shadow call stack dynamically using code patching"
2175	# needs Clang with https://reviews.llvm.org/D111780 incorporated
2176	depends on CC_IS_CLANG && CLANG_VERSION >= 150000
2177	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2178	depends on SHADOW_CALL_STACK
2179	select UNWIND_TABLES
2180	select DYNAMIC_SCS
2181
2182endmenu # "Kernel Features"
2183
2184menu "Boot options"
2185
2186config ARM64_ACPI_PARKING_PROTOCOL
2187	bool "Enable support for the ARM64 ACPI parking protocol"
2188	depends on ACPI
2189	help
2190	  Enable support for the ARM64 ACPI parking protocol. If disabled
2191	  the kernel will not allow booting through the ARM64 ACPI parking
2192	  protocol even if the corresponding data is present in the ACPI
2193	  MADT table.
2194
2195config CMDLINE
2196	string "Default kernel command string"
2197	default ""
2198	help
2199	  Provide a set of default command-line options at build time by
2200	  entering them here. As a minimum, you should specify the the
2201	  root device (e.g. root=/dev/nfs).
2202
2203choice
2204	prompt "Kernel command line type" if CMDLINE != ""
2205	default CMDLINE_FROM_BOOTLOADER
2206	help
2207	  Choose how the kernel will handle the provided default kernel
2208	  command line string.
2209
2210config CMDLINE_FROM_BOOTLOADER
2211	bool "Use bootloader kernel arguments if available"
2212	help
2213	  Uses the command-line options passed by the boot loader. If
2214	  the boot loader doesn't provide any, the default kernel command
2215	  string provided in CMDLINE will be used.
2216
2217config CMDLINE_FORCE
2218	bool "Always use the default kernel command string"
2219	help
2220	  Always use the default kernel command string, even if the boot
2221	  loader passes other arguments to the kernel.
2222	  This is useful if you cannot or don't want to change the
2223	  command-line options your boot loader passes to the kernel.
2224
2225endchoice
2226
2227config EFI_STUB
2228	bool
2229
2230config EFI
2231	bool "UEFI runtime support"
2232	depends on OF && !CPU_BIG_ENDIAN
2233	depends on KERNEL_MODE_NEON
2234	select ARCH_SUPPORTS_ACPI
2235	select LIBFDT
2236	select UCS2_STRING
2237	select EFI_PARAMS_FROM_FDT
2238	select EFI_RUNTIME_WRAPPERS
2239	select EFI_STUB
2240	select EFI_GENERIC_STUB
2241	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2242	default y
2243	help
2244	  This option provides support for runtime services provided
2245	  by UEFI firmware (such as non-volatile variables, realtime
2246	  clock, and platform reset). A UEFI stub is also provided to
2247	  allow the kernel to be booted as an EFI application. This
2248	  is only useful on systems that have UEFI firmware.
2249
2250config DMI
2251	bool "Enable support for SMBIOS (DMI) tables"
2252	depends on EFI
2253	default y
2254	help
2255	  This enables SMBIOS/DMI feature for systems.
2256
2257	  This option is only useful on systems that have UEFI firmware.
2258	  However, even with this option, the resultant kernel should
2259	  continue to boot on existing non-UEFI platforms.
2260
2261endmenu # "Boot options"
2262
2263menu "Power management options"
2264
2265source "kernel/power/Kconfig"
2266
2267config ARCH_HIBERNATION_POSSIBLE
2268	def_bool y
2269	depends on CPU_PM
2270
2271config ARCH_HIBERNATION_HEADER
2272	def_bool y
2273	depends on HIBERNATION
2274
2275config ARCH_SUSPEND_POSSIBLE
2276	def_bool y
2277
2278endmenu # "Power management options"
2279
2280menu "CPU Power Management"
2281
2282source "drivers/cpuidle/Kconfig"
2283
2284source "drivers/cpufreq/Kconfig"
2285
2286endmenu # "CPU Power Management"
2287
2288source "drivers/acpi/Kconfig"
2289
2290source "arch/arm64/kvm/Kconfig"
2291
2292