xref: /openbmc/linux/arch/arm64/Kconfig (revision d21077fb)
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_SUPPORTS_PER_VMA_LOCK
99	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
100	select ARCH_WANT_DEFAULT_BPF_JIT
101	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
102	select ARCH_WANT_FRAME_POINTERS
103	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
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_CALL_OPS \
190		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG && \
191		    !CC_OPTIMIZE_FOR_SIZE)
192	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
193		if DYNAMIC_FTRACE_WITH_ARGS
194	select HAVE_EFFICIENT_UNALIGNED_ACCESS
195	select HAVE_FAST_GUP
196	select HAVE_FTRACE_MCOUNT_RECORD
197	select HAVE_FUNCTION_TRACER
198	select HAVE_FUNCTION_ERROR_INJECTION
199	select HAVE_FUNCTION_GRAPH_TRACER
200	select HAVE_GCC_PLUGINS
201	select HAVE_HW_BREAKPOINT if PERF_EVENTS
202	select HAVE_IOREMAP_PROT
203	select HAVE_IRQ_TIME_ACCOUNTING
204	select HAVE_KVM
205	select HAVE_NMI
206	select HAVE_PERF_EVENTS
207	select HAVE_PERF_REGS
208	select HAVE_PERF_USER_STACK_DUMP
209	select HAVE_PREEMPT_DYNAMIC_KEY
210	select HAVE_REGS_AND_STACK_ACCESS_API
211	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
212	select HAVE_FUNCTION_ARG_ACCESS_API
213	select MMU_GATHER_RCU_TABLE_FREE
214	select HAVE_RSEQ
215	select HAVE_STACKPROTECTOR
216	select HAVE_SYSCALL_TRACEPOINTS
217	select HAVE_KPROBES
218	select HAVE_KRETPROBES
219	select HAVE_GENERIC_VDSO
220	select IRQ_DOMAIN
221	select IRQ_FORCED_THREADING
222	select KASAN_VMALLOC if KASAN
223	select MODULES_USE_ELF_RELA
224	select NEED_DMA_MAP_STATE
225	select NEED_SG_DMA_LENGTH
226	select OF
227	select OF_EARLY_FLATTREE
228	select PCI_DOMAINS_GENERIC if PCI
229	select PCI_ECAM if (ACPI && PCI)
230	select PCI_SYSCALL if PCI
231	select POWER_RESET
232	select POWER_SUPPLY
233	select SPARSE_IRQ
234	select SWIOTLB
235	select SYSCTL_EXCEPTION_TRACE
236	select THREAD_INFO_IN_TASK
237	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
238	select TRACE_IRQFLAGS_SUPPORT
239	select TRACE_IRQFLAGS_NMI_SUPPORT
240	select HAVE_SOFTIRQ_ON_OWN_STACK
241	help
242	  ARM 64-bit (AArch64) Linux support.
243
244config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
245	def_bool CC_IS_CLANG
246	# https://github.com/ClangBuiltLinux/linux/issues/1507
247	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
248	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
249
250config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
251	def_bool CC_IS_GCC
252	depends on $(cc-option,-fpatchable-function-entry=2)
253	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
254
255config 64BIT
256	def_bool y
257
258config MMU
259	def_bool y
260
261config ARM64_PAGE_SHIFT
262	int
263	default 16 if ARM64_64K_PAGES
264	default 14 if ARM64_16K_PAGES
265	default 12
266
267config ARM64_CONT_PTE_SHIFT
268	int
269	default 5 if ARM64_64K_PAGES
270	default 7 if ARM64_16K_PAGES
271	default 4
272
273config ARM64_CONT_PMD_SHIFT
274	int
275	default 5 if ARM64_64K_PAGES
276	default 5 if ARM64_16K_PAGES
277	default 4
278
279config ARCH_MMAP_RND_BITS_MIN
280	default 14 if ARM64_64K_PAGES
281	default 16 if ARM64_16K_PAGES
282	default 18
283
284# max bits determined by the following formula:
285#  VA_BITS - PAGE_SHIFT - 3
286config ARCH_MMAP_RND_BITS_MAX
287	default 19 if ARM64_VA_BITS=36
288	default 24 if ARM64_VA_BITS=39
289	default 27 if ARM64_VA_BITS=42
290	default 30 if ARM64_VA_BITS=47
291	default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
292	default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
293	default 33 if ARM64_VA_BITS=48
294	default 14 if ARM64_64K_PAGES
295	default 16 if ARM64_16K_PAGES
296	default 18
297
298config ARCH_MMAP_RND_COMPAT_BITS_MIN
299	default 7 if ARM64_64K_PAGES
300	default 9 if ARM64_16K_PAGES
301	default 11
302
303config ARCH_MMAP_RND_COMPAT_BITS_MAX
304	default 16
305
306config NO_IOPORT_MAP
307	def_bool y if !PCI
308
309config STACKTRACE_SUPPORT
310	def_bool y
311
312config ILLEGAL_POINTER_VALUE
313	hex
314	default 0xdead000000000000
315
316config LOCKDEP_SUPPORT
317	def_bool y
318
319config GENERIC_BUG
320	def_bool y
321	depends on BUG
322
323config GENERIC_BUG_RELATIVE_POINTERS
324	def_bool y
325	depends on GENERIC_BUG
326
327config GENERIC_HWEIGHT
328	def_bool y
329
330config GENERIC_CSUM
331	def_bool y
332
333config GENERIC_CALIBRATE_DELAY
334	def_bool y
335
336config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
337	def_bool y
338
339config SMP
340	def_bool y
341
342config KERNEL_MODE_NEON
343	def_bool y
344
345config FIX_EARLYCON_MEM
346	def_bool y
347
348config PGTABLE_LEVELS
349	int
350	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
351	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
352	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
353	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
354	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
355	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
356
357config ARCH_SUPPORTS_UPROBES
358	def_bool y
359
360config ARCH_PROC_KCORE_TEXT
361	def_bool y
362
363config BROKEN_GAS_INST
364	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
365
366config KASAN_SHADOW_OFFSET
367	hex
368	depends on KASAN_GENERIC || KASAN_SW_TAGS
369	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
370	default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
371	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
372	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
373	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
374	default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
375	default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
376	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
377	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
378	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
379	default 0xffffffffffffffff
380
381config UNWIND_TABLES
382	bool
383
384source "arch/arm64/Kconfig.platforms"
385
386menu "Kernel Features"
387
388menu "ARM errata workarounds via the alternatives framework"
389
390config ARM64_WORKAROUND_CLEAN_CACHE
391	bool
392
393config ARM64_ERRATUM_826319
394	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
395	default y
396	select ARM64_WORKAROUND_CLEAN_CACHE
397	help
398	  This option adds an alternative code sequence to work around ARM
399	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
400	  AXI master interface and an L2 cache.
401
402	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
403	  and is unable to accept a certain write via this interface, it will
404	  not progress on read data presented on the read data channel and the
405	  system can deadlock.
406
407	  The workaround promotes data cache clean instructions to
408	  data cache clean-and-invalidate.
409	  Please note that this does not necessarily enable the workaround,
410	  as it depends on the alternative framework, which will only patch
411	  the kernel if an affected CPU is detected.
412
413	  If unsure, say Y.
414
415config ARM64_ERRATUM_827319
416	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
417	default y
418	select ARM64_WORKAROUND_CLEAN_CACHE
419	help
420	  This option adds an alternative code sequence to work around ARM
421	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
422	  master interface and an L2 cache.
423
424	  Under certain conditions this erratum can cause a clean line eviction
425	  to occur at the same time as another transaction to the same address
426	  on the AMBA 5 CHI interface, which can cause data corruption if the
427	  interconnect reorders the two transactions.
428
429	  The workaround promotes data cache clean instructions to
430	  data cache clean-and-invalidate.
431	  Please note that this does not necessarily enable the workaround,
432	  as it depends on the alternative framework, which will only patch
433	  the kernel if an affected CPU is detected.
434
435	  If unsure, say Y.
436
437config ARM64_ERRATUM_824069
438	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
439	default y
440	select ARM64_WORKAROUND_CLEAN_CACHE
441	help
442	  This option adds an alternative code sequence to work around ARM
443	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
444	  to a coherent interconnect.
445
446	  If a Cortex-A53 processor is executing a store or prefetch for
447	  write instruction at the same time as a processor in another
448	  cluster is executing a cache maintenance operation to the same
449	  address, then this erratum might cause a clean cache line to be
450	  incorrectly marked as dirty.
451
452	  The workaround promotes data cache clean instructions to
453	  data cache clean-and-invalidate.
454	  Please note that this option does not necessarily enable the
455	  workaround, as it depends on the alternative framework, which will
456	  only patch the kernel if an affected CPU is detected.
457
458	  If unsure, say Y.
459
460config ARM64_ERRATUM_819472
461	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
462	default y
463	select ARM64_WORKAROUND_CLEAN_CACHE
464	help
465	  This option adds an alternative code sequence to work around ARM
466	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
467	  present when it is connected to a coherent interconnect.
468
469	  If the processor is executing a load and store exclusive sequence at
470	  the same time as a processor in another cluster is executing a cache
471	  maintenance operation to the same address, then this erratum might
472	  cause data corruption.
473
474	  The workaround promotes data cache clean instructions to
475	  data cache clean-and-invalidate.
476	  Please note that this does not necessarily enable the workaround,
477	  as it depends on the alternative framework, which will only patch
478	  the kernel if an affected CPU is detected.
479
480	  If unsure, say Y.
481
482config ARM64_ERRATUM_832075
483	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
484	default y
485	help
486	  This option adds an alternative code sequence to work around ARM
487	  erratum 832075 on Cortex-A57 parts up to r1p2.
488
489	  Affected Cortex-A57 parts might deadlock when exclusive load/store
490	  instructions to Write-Back memory are mixed with Device loads.
491
492	  The workaround is to promote device loads to use Load-Acquire
493	  semantics.
494	  Please note that this does not necessarily enable the workaround,
495	  as it depends on the alternative framework, which will only patch
496	  the kernel if an affected CPU is detected.
497
498	  If unsure, say Y.
499
500config ARM64_ERRATUM_834220
501	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
502	depends on KVM
503	default y
504	help
505	  This option adds an alternative code sequence to work around ARM
506	  erratum 834220 on Cortex-A57 parts up to r1p2.
507
508	  Affected Cortex-A57 parts might report a Stage 2 translation
509	  fault as the result of a Stage 1 fault for load crossing a
510	  page boundary when there is a permission or device memory
511	  alignment fault at Stage 1 and a translation fault at Stage 2.
512
513	  The workaround is to verify that the Stage 1 translation
514	  doesn't generate a fault before handling the Stage 2 fault.
515	  Please note that this does not necessarily enable the workaround,
516	  as it depends on the alternative framework, which will only patch
517	  the kernel if an affected CPU is detected.
518
519	  If unsure, say Y.
520
521config ARM64_ERRATUM_1742098
522	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
523	depends on COMPAT
524	default y
525	help
526	  This option removes the AES hwcap for aarch32 user-space to
527	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
528
529	  Affected parts may corrupt the AES state if an interrupt is
530	  taken between a pair of AES instructions. These instructions
531	  are only present if the cryptography extensions are present.
532	  All software should have a fallback implementation for CPUs
533	  that don't implement the cryptography extensions.
534
535	  If unsure, say Y.
536
537config ARM64_ERRATUM_845719
538	bool "Cortex-A53: 845719: a load might read incorrect data"
539	depends on COMPAT
540	default y
541	help
542	  This option adds an alternative code sequence to work around ARM
543	  erratum 845719 on Cortex-A53 parts up to r0p4.
544
545	  When running a compat (AArch32) userspace on an affected Cortex-A53
546	  part, a load at EL0 from a virtual address that matches the bottom 32
547	  bits of the virtual address used by a recent load at (AArch64) EL1
548	  might return incorrect data.
549
550	  The workaround is to write the contextidr_el1 register on exception
551	  return to a 32-bit task.
552	  Please note that this does not necessarily enable the workaround,
553	  as it depends on the alternative framework, which will only patch
554	  the kernel if an affected CPU is detected.
555
556	  If unsure, say Y.
557
558config ARM64_ERRATUM_843419
559	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
560	default y
561	select ARM64_MODULE_PLTS if MODULES
562	help
563	  This option links the kernel with '--fix-cortex-a53-843419' and
564	  enables PLT support to replace certain ADRP instructions, which can
565	  cause subsequent memory accesses to use an incorrect address on
566	  Cortex-A53 parts up to r0p4.
567
568	  If unsure, say Y.
569
570config ARM64_LD_HAS_FIX_ERRATUM_843419
571	def_bool $(ld-option,--fix-cortex-a53-843419)
572
573config ARM64_ERRATUM_1024718
574	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
575	default y
576	help
577	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
578
579	  Affected Cortex-A55 cores (all revisions) could cause incorrect
580	  update of the hardware dirty bit when the DBM/AP bits are updated
581	  without a break-before-make. The workaround is to disable the usage
582	  of hardware DBM locally on the affected cores. CPUs not affected by
583	  this erratum will continue to use the feature.
584
585	  If unsure, say Y.
586
587config ARM64_ERRATUM_1418040
588	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
589	default y
590	depends on COMPAT
591	help
592	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
593	  errata 1188873 and 1418040.
594
595	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
596	  cause register corruption when accessing the timer registers
597	  from AArch32 userspace.
598
599	  If unsure, say Y.
600
601config ARM64_WORKAROUND_SPECULATIVE_AT
602	bool
603
604config ARM64_ERRATUM_1165522
605	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
606	default y
607	select ARM64_WORKAROUND_SPECULATIVE_AT
608	help
609	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
610
611	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
612	  corrupted TLBs by speculating an AT instruction during a guest
613	  context switch.
614
615	  If unsure, say Y.
616
617config ARM64_ERRATUM_1319367
618	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
619	default y
620	select ARM64_WORKAROUND_SPECULATIVE_AT
621	help
622	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
623	  and A72 erratum 1319367
624
625	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
626	  speculating an AT instruction during a guest context switch.
627
628	  If unsure, say Y.
629
630config ARM64_ERRATUM_1530923
631	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
632	default y
633	select ARM64_WORKAROUND_SPECULATIVE_AT
634	help
635	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
636
637	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
638	  corrupted TLBs by speculating an AT instruction during a guest
639	  context switch.
640
641	  If unsure, say Y.
642
643config ARM64_WORKAROUND_REPEAT_TLBI
644	bool
645
646config ARM64_ERRATUM_2441007
647	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
648	default y
649	select ARM64_WORKAROUND_REPEAT_TLBI
650	help
651	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
652
653	  Under very rare circumstances, affected Cortex-A55 CPUs
654	  may not handle a race between a break-before-make sequence on one
655	  CPU, and another CPU accessing the same page. This could allow a
656	  store to a page that has been unmapped.
657
658	  Work around this by adding the affected CPUs to the list that needs
659	  TLB sequences to be done twice.
660
661	  If unsure, say Y.
662
663config ARM64_ERRATUM_1286807
664	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
665	default y
666	select ARM64_WORKAROUND_REPEAT_TLBI
667	help
668	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
669
670	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
671	  address for a cacheable mapping of a location is being
672	  accessed by a core while another core is remapping the virtual
673	  address to a new physical page using the recommended
674	  break-before-make sequence, then under very rare circumstances
675	  TLBI+DSB completes before a read using the translation being
676	  invalidated has been observed by other observers. The
677	  workaround repeats the TLBI+DSB operation.
678
679config ARM64_ERRATUM_1463225
680	bool "Cortex-A76: Software Step might prevent interrupt recognition"
681	default y
682	help
683	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
684
685	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
686	  of a system call instruction (SVC) can prevent recognition of
687	  subsequent interrupts when software stepping is disabled in the
688	  exception handler of the system call and either kernel debugging
689	  is enabled or VHE is in use.
690
691	  Work around the erratum by triggering a dummy step exception
692	  when handling a system call from a task that is being stepped
693	  in a VHE configuration of the kernel.
694
695	  If unsure, say Y.
696
697config ARM64_ERRATUM_1542419
698	bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
699	default y
700	help
701	  This option adds a workaround for ARM Neoverse-N1 erratum
702	  1542419.
703
704	  Affected Neoverse-N1 cores could execute a stale instruction when
705	  modified by another CPU. The workaround depends on a firmware
706	  counterpart.
707
708	  Workaround the issue by hiding the DIC feature from EL0. This
709	  forces user-space to perform cache maintenance.
710
711	  If unsure, say Y.
712
713config ARM64_ERRATUM_1508412
714	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
715	default y
716	help
717	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
718
719	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
720	  of a store-exclusive or read of PAR_EL1 and a load with device or
721	  non-cacheable memory attributes. The workaround depends on a firmware
722	  counterpart.
723
724	  KVM guests must also have the workaround implemented or they can
725	  deadlock the system.
726
727	  Work around the issue by inserting DMB SY barriers around PAR_EL1
728	  register reads and warning KVM users. The DMB barrier is sufficient
729	  to prevent a speculative PAR_EL1 read.
730
731	  If unsure, say Y.
732
733config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
734	bool
735
736config ARM64_ERRATUM_2051678
737	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
738	default y
739	help
740	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
741	  Affected Cortex-A510 might not respect the ordering rules for
742	  hardware update of the page table's dirty bit. The workaround
743	  is to not enable the feature on affected CPUs.
744
745	  If unsure, say Y.
746
747config ARM64_ERRATUM_2077057
748	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
749	default y
750	help
751	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
752	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
753	  expected, but a Pointer Authentication trap is taken instead. The
754	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
755	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
756
757	  This can only happen when EL2 is stepping EL1.
758
759	  When these conditions occur, the SPSR_EL2 value is unchanged from the
760	  previous guest entry, and can be restored from the in-memory copy.
761
762	  If unsure, say Y.
763
764config ARM64_ERRATUM_2658417
765	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
766	default y
767	help
768	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
769	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
770	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
771	  A510 CPUs are using shared neon hardware. As the sharing is not
772	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
773	  user-space should not be using these instructions.
774
775	  If unsure, say Y.
776
777config ARM64_ERRATUM_2119858
778	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
779	default y
780	depends on CORESIGHT_TRBE
781	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
782	help
783	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
784
785	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
786	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
787	  the event of a WRAP event.
788
789	  Work around the issue by always making sure we move the TRBPTR_EL1 by
790	  256 bytes before enabling the buffer and filling the first 256 bytes of
791	  the buffer with ETM ignore packets upon disabling.
792
793	  If unsure, say Y.
794
795config ARM64_ERRATUM_2139208
796	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
797	default y
798	depends on CORESIGHT_TRBE
799	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
800	help
801	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
802
803	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
804	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
805	  the event of a WRAP event.
806
807	  Work around the issue by always making sure we move the TRBPTR_EL1 by
808	  256 bytes before enabling the buffer and filling the first 256 bytes of
809	  the buffer with ETM ignore packets upon disabling.
810
811	  If unsure, say Y.
812
813config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
814	bool
815
816config ARM64_ERRATUM_2054223
817	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
818	default y
819	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
820	help
821	  Enable workaround for ARM Cortex-A710 erratum 2054223
822
823	  Affected cores may fail to flush the trace data on a TSB instruction, when
824	  the PE is in trace prohibited state. This will cause losing a few bytes
825	  of the trace cached.
826
827	  Workaround is to issue two TSB consecutively on affected cores.
828
829	  If unsure, say Y.
830
831config ARM64_ERRATUM_2067961
832	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
833	default y
834	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
835	help
836	  Enable workaround for ARM Neoverse-N2 erratum 2067961
837
838	  Affected cores may fail to flush the trace data on a TSB instruction, when
839	  the PE is in trace prohibited state. This will cause losing a few bytes
840	  of the trace cached.
841
842	  Workaround is to issue two TSB consecutively on affected cores.
843
844	  If unsure, say Y.
845
846config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
847	bool
848
849config ARM64_ERRATUM_2253138
850	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
851	depends on CORESIGHT_TRBE
852	default y
853	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
854	help
855	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
856
857	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
858	  for TRBE. Under some conditions, the TRBE might generate a write to the next
859	  virtually addressed page following the last page of the TRBE address space
860	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
861
862	  Work around this in the driver by always making sure that there is a
863	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
864
865	  If unsure, say Y.
866
867config ARM64_ERRATUM_2224489
868	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
869	depends on CORESIGHT_TRBE
870	default y
871	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
872	help
873	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
874
875	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
876	  for TRBE. Under some conditions, the TRBE might generate a write to the next
877	  virtually addressed page following the last page of the TRBE address space
878	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
879
880	  Work around this in the driver by always making sure that there is a
881	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
882
883	  If unsure, say Y.
884
885config ARM64_ERRATUM_2441009
886	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
887	default y
888	select ARM64_WORKAROUND_REPEAT_TLBI
889	help
890	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
891
892	  Under very rare circumstances, affected Cortex-A510 CPUs
893	  may not handle a race between a break-before-make sequence on one
894	  CPU, and another CPU accessing the same page. This could allow a
895	  store to a page that has been unmapped.
896
897	  Work around this by adding the affected CPUs to the list that needs
898	  TLB sequences to be done twice.
899
900	  If unsure, say Y.
901
902config ARM64_ERRATUM_2064142
903	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
904	depends on CORESIGHT_TRBE
905	default y
906	help
907	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
908
909	  Affected Cortex-A510 core might fail to write into system registers after the
910	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
911	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
912	  and TRBTRG_EL1 will be ignored and will not be effected.
913
914	  Work around this in the driver by executing TSB CSYNC and DSB after collection
915	  is stopped and before performing a system register write to one of the affected
916	  registers.
917
918	  If unsure, say Y.
919
920config ARM64_ERRATUM_2038923
921	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
922	depends on CORESIGHT_TRBE
923	default y
924	help
925	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
926
927	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
928	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
929	  might be corrupted. This happens after TRBE buffer has been enabled by setting
930	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
931	  execution changes from a context, in which trace is prohibited to one where it
932	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
933	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
934	  the trace buffer state might be corrupted.
935
936	  Work around this in the driver by preventing an inconsistent view of whether the
937	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
938	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
939	  two ISB instructions if no ERET is to take place.
940
941	  If unsure, say Y.
942
943config ARM64_ERRATUM_1902691
944	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
945	depends on CORESIGHT_TRBE
946	default y
947	help
948	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
949
950	  Affected Cortex-A510 core might cause trace data corruption, when being written
951	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
952	  trace data.
953
954	  Work around this problem in the driver by just preventing TRBE initialization on
955	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
956	  on such implementations. This will cover the kernel for any firmware that doesn't
957	  do this already.
958
959	  If unsure, say Y.
960
961config ARM64_ERRATUM_2457168
962	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
963	depends on ARM64_AMU_EXTN
964	default y
965	help
966	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
967
968	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
969	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
970	  incorrectly giving a significantly higher output value.
971
972	  Work around this problem by returning 0 when reading the affected counter in
973	  key locations that results in disabling all users of this counter. This effect
974	  is the same to firmware disabling affected counters.
975
976	  If unsure, say Y.
977
978config ARM64_ERRATUM_2645198
979	bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
980	default y
981	help
982	  This option adds the workaround for ARM Cortex-A715 erratum 2645198.
983
984	  If a Cortex-A715 cpu sees a page mapping permissions change from executable
985	  to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
986	  next instruction abort caused by permission fault.
987
988	  Only user-space does executable to non-executable permission transition via
989	  mprotect() system call. Workaround the problem by doing a break-before-make
990	  TLB invalidation, for all changes to executable user space mappings.
991
992	  If unsure, say Y.
993
994config CAVIUM_ERRATUM_22375
995	bool "Cavium erratum 22375, 24313"
996	default y
997	help
998	  Enable workaround for errata 22375 and 24313.
999
1000	  This implements two gicv3-its errata workarounds for ThunderX. Both
1001	  with a small impact affecting only ITS table allocation.
1002
1003	    erratum 22375: only alloc 8MB table size
1004	    erratum 24313: ignore memory access type
1005
1006	  The fixes are in ITS initialization and basically ignore memory access
1007	  type and table size provided by the TYPER and BASER registers.
1008
1009	  If unsure, say Y.
1010
1011config CAVIUM_ERRATUM_23144
1012	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1013	depends on NUMA
1014	default y
1015	help
1016	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1017
1018	  If unsure, say Y.
1019
1020config CAVIUM_ERRATUM_23154
1021	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1022	default y
1023	help
1024	  The ThunderX GICv3 implementation requires a modified version for
1025	  reading the IAR status to ensure data synchronization
1026	  (access to icc_iar1_el1 is not sync'ed before and after).
1027
1028	  It also suffers from erratum 38545 (also present on Marvell's
1029	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1030	  spuriously presented to the CPU interface.
1031
1032	  If unsure, say Y.
1033
1034config CAVIUM_ERRATUM_27456
1035	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1036	default y
1037	help
1038	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1039	  instructions may cause the icache to become corrupted if it
1040	  contains data for a non-current ASID.  The fix is to
1041	  invalidate the icache when changing the mm context.
1042
1043	  If unsure, say Y.
1044
1045config CAVIUM_ERRATUM_30115
1046	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1047	default y
1048	help
1049	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1050	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1051	  interrupts in host. Trapping both GICv3 group-0 and group-1
1052	  accesses sidesteps the issue.
1053
1054	  If unsure, say Y.
1055
1056config CAVIUM_TX2_ERRATUM_219
1057	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1058	default y
1059	help
1060	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1061	  TTBR update and the corresponding context synchronizing operation can
1062	  cause a spurious Data Abort to be delivered to any hardware thread in
1063	  the CPU core.
1064
1065	  Work around the issue by avoiding the problematic code sequence and
1066	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1067	  trap handler performs the corresponding register access, skips the
1068	  instruction and ensures context synchronization by virtue of the
1069	  exception return.
1070
1071	  If unsure, say Y.
1072
1073config FUJITSU_ERRATUM_010001
1074	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1075	default y
1076	help
1077	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1078	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1079	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1080	  This fault occurs under a specific hardware condition when a
1081	  load/store instruction performs an address translation using:
1082	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1083	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1084	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1085	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1086
1087	  The workaround is to ensure these bits are clear in TCR_ELx.
1088	  The workaround only affects the Fujitsu-A64FX.
1089
1090	  If unsure, say Y.
1091
1092config HISILICON_ERRATUM_161600802
1093	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1094	default y
1095	help
1096	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1097	  when issued ITS commands such as VMOVP and VMAPP, and requires
1098	  a 128kB offset to be applied to the target address in this commands.
1099
1100	  If unsure, say Y.
1101
1102config QCOM_FALKOR_ERRATUM_1003
1103	bool "Falkor E1003: Incorrect translation due to ASID change"
1104	default y
1105	help
1106	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1107	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1108	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1109	  then only for entries in the walk cache, since the leaf translation
1110	  is unchanged. Work around the erratum by invalidating the walk cache
1111	  entries for the trampoline before entering the kernel proper.
1112
1113config QCOM_FALKOR_ERRATUM_1009
1114	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1115	default y
1116	select ARM64_WORKAROUND_REPEAT_TLBI
1117	help
1118	  On Falkor v1, the CPU may prematurely complete a DSB following a
1119	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1120	  one more time to fix the issue.
1121
1122	  If unsure, say Y.
1123
1124config QCOM_QDF2400_ERRATUM_0065
1125	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1126	default y
1127	help
1128	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1129	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1130	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1131
1132	  If unsure, say Y.
1133
1134config QCOM_FALKOR_ERRATUM_E1041
1135	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1136	default y
1137	help
1138	  Falkor CPU may speculatively fetch instructions from an improper
1139	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1140	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1141
1142	  If unsure, say Y.
1143
1144config NVIDIA_CARMEL_CNP_ERRATUM
1145	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1146	default y
1147	help
1148	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1149	  invalidate shared TLB entries installed by a different core, as it would
1150	  on standard ARM cores.
1151
1152	  If unsure, say Y.
1153
1154config SOCIONEXT_SYNQUACER_PREITS
1155	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1156	default y
1157	help
1158	  Socionext Synquacer SoCs implement a separate h/w block to generate
1159	  MSI doorbell writes with non-zero values for the device ID.
1160
1161	  If unsure, say Y.
1162
1163endmenu # "ARM errata workarounds via the alternatives framework"
1164
1165choice
1166	prompt "Page size"
1167	default ARM64_4K_PAGES
1168	help
1169	  Page size (translation granule) configuration.
1170
1171config ARM64_4K_PAGES
1172	bool "4KB"
1173	help
1174	  This feature enables 4KB pages support.
1175
1176config ARM64_16K_PAGES
1177	bool "16KB"
1178	help
1179	  The system will use 16KB pages support. AArch32 emulation
1180	  requires applications compiled with 16K (or a multiple of 16K)
1181	  aligned segments.
1182
1183config ARM64_64K_PAGES
1184	bool "64KB"
1185	help
1186	  This feature enables 64KB pages support (4KB by default)
1187	  allowing only two levels of page tables and faster TLB
1188	  look-up. AArch32 emulation requires applications compiled
1189	  with 64K aligned segments.
1190
1191endchoice
1192
1193choice
1194	prompt "Virtual address space size"
1195	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
1196	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
1197	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
1198	help
1199	  Allows choosing one of multiple possible virtual address
1200	  space sizes. The level of translation table is determined by
1201	  a combination of page size and virtual address space size.
1202
1203config ARM64_VA_BITS_36
1204	bool "36-bit" if EXPERT
1205	depends on ARM64_16K_PAGES
1206
1207config ARM64_VA_BITS_39
1208	bool "39-bit"
1209	depends on ARM64_4K_PAGES
1210
1211config ARM64_VA_BITS_42
1212	bool "42-bit"
1213	depends on ARM64_64K_PAGES
1214
1215config ARM64_VA_BITS_47
1216	bool "47-bit"
1217	depends on ARM64_16K_PAGES
1218
1219config ARM64_VA_BITS_48
1220	bool "48-bit"
1221
1222config ARM64_VA_BITS_52
1223	bool "52-bit"
1224	depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
1225	help
1226	  Enable 52-bit virtual addressing for userspace when explicitly
1227	  requested via a hint to mmap(). The kernel will also use 52-bit
1228	  virtual addresses for its own mappings (provided HW support for
1229	  this feature is available, otherwise it reverts to 48-bit).
1230
1231	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1232	  ARMv8.3 Pointer Authentication will result in the PAC being
1233	  reduced from 7 bits to 3 bits, which may have a significant
1234	  impact on its susceptibility to brute-force attacks.
1235
1236	  If unsure, select 48-bit virtual addressing instead.
1237
1238endchoice
1239
1240config ARM64_FORCE_52BIT
1241	bool "Force 52-bit virtual addresses for userspace"
1242	depends on ARM64_VA_BITS_52 && EXPERT
1243	help
1244	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1245	  to maintain compatibility with older software by providing 48-bit VAs
1246	  unless a hint is supplied to mmap.
1247
1248	  This configuration option disables the 48-bit compatibility logic, and
1249	  forces all userspace addresses to be 52-bit on HW that supports it. One
1250	  should only enable this configuration option for stress testing userspace
1251	  memory management code. If unsure say N here.
1252
1253config ARM64_VA_BITS
1254	int
1255	default 36 if ARM64_VA_BITS_36
1256	default 39 if ARM64_VA_BITS_39
1257	default 42 if ARM64_VA_BITS_42
1258	default 47 if ARM64_VA_BITS_47
1259	default 48 if ARM64_VA_BITS_48
1260	default 52 if ARM64_VA_BITS_52
1261
1262choice
1263	prompt "Physical address space size"
1264	default ARM64_PA_BITS_48
1265	help
1266	  Choose the maximum physical address range that the kernel will
1267	  support.
1268
1269config ARM64_PA_BITS_48
1270	bool "48-bit"
1271
1272config ARM64_PA_BITS_52
1273	bool "52-bit (ARMv8.2)"
1274	depends on ARM64_64K_PAGES
1275	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1276	help
1277	  Enable support for a 52-bit physical address space, introduced as
1278	  part of the ARMv8.2-LPA extension.
1279
1280	  With this enabled, the kernel will also continue to work on CPUs that
1281	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1282	  minor performance overhead).
1283
1284endchoice
1285
1286config ARM64_PA_BITS
1287	int
1288	default 48 if ARM64_PA_BITS_48
1289	default 52 if ARM64_PA_BITS_52
1290
1291choice
1292	prompt "Endianness"
1293	default CPU_LITTLE_ENDIAN
1294	help
1295	  Select the endianness of data accesses performed by the CPU. Userspace
1296	  applications will need to be compiled and linked for the endianness
1297	  that is selected here.
1298
1299config CPU_BIG_ENDIAN
1300	bool "Build big-endian kernel"
1301	depends on !LD_IS_LLD || LLD_VERSION >= 130000
1302	help
1303	  Say Y if you plan on running a kernel with a big-endian userspace.
1304
1305config CPU_LITTLE_ENDIAN
1306	bool "Build little-endian kernel"
1307	help
1308	  Say Y if you plan on running a kernel with a little-endian userspace.
1309	  This is usually the case for distributions targeting arm64.
1310
1311endchoice
1312
1313config SCHED_MC
1314	bool "Multi-core scheduler support"
1315	help
1316	  Multi-core scheduler support improves the CPU scheduler's decision
1317	  making when dealing with multi-core CPU chips at a cost of slightly
1318	  increased overhead in some places. If unsure say N here.
1319
1320config SCHED_CLUSTER
1321	bool "Cluster scheduler support"
1322	help
1323	  Cluster scheduler support improves the CPU scheduler's decision
1324	  making when dealing with machines that have clusters of CPUs.
1325	  Cluster usually means a couple of CPUs which are placed closely
1326	  by sharing mid-level caches, last-level cache tags or internal
1327	  busses.
1328
1329config SCHED_SMT
1330	bool "SMT scheduler support"
1331	help
1332	  Improves the CPU scheduler's decision making when dealing with
1333	  MultiThreading at a cost of slightly increased overhead in some
1334	  places. If unsure say N here.
1335
1336config NR_CPUS
1337	int "Maximum number of CPUs (2-4096)"
1338	range 2 4096
1339	default "256"
1340
1341config HOTPLUG_CPU
1342	bool "Support for hot-pluggable CPUs"
1343	select GENERIC_IRQ_MIGRATION
1344	help
1345	  Say Y here to experiment with turning CPUs off and on.  CPUs
1346	  can be controlled through /sys/devices/system/cpu.
1347
1348# Common NUMA Features
1349config NUMA
1350	bool "NUMA Memory Allocation and Scheduler Support"
1351	select GENERIC_ARCH_NUMA
1352	select ACPI_NUMA if ACPI
1353	select OF_NUMA
1354	select HAVE_SETUP_PER_CPU_AREA
1355	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1356	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1357	select USE_PERCPU_NUMA_NODE_ID
1358	help
1359	  Enable NUMA (Non-Uniform Memory Access) support.
1360
1361	  The kernel will try to allocate memory used by a CPU on the
1362	  local memory of the CPU and add some more
1363	  NUMA awareness to the kernel.
1364
1365config NODES_SHIFT
1366	int "Maximum NUMA Nodes (as a power of 2)"
1367	range 1 10
1368	default "4"
1369	depends on NUMA
1370	help
1371	  Specify the maximum number of NUMA Nodes available on the target
1372	  system.  Increases memory reserved to accommodate various tables.
1373
1374source "kernel/Kconfig.hz"
1375
1376config ARCH_SPARSEMEM_ENABLE
1377	def_bool y
1378	select SPARSEMEM_VMEMMAP_ENABLE
1379	select SPARSEMEM_VMEMMAP
1380
1381config HW_PERF_EVENTS
1382	def_bool y
1383	depends on ARM_PMU
1384
1385# Supported by clang >= 7.0 or GCC >= 12.0.0
1386config CC_HAVE_SHADOW_CALL_STACK
1387	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1388
1389config PARAVIRT
1390	bool "Enable paravirtualization code"
1391	help
1392	  This changes the kernel so it can modify itself when it is run
1393	  under a hypervisor, potentially improving performance significantly
1394	  over full virtualization.
1395
1396config PARAVIRT_TIME_ACCOUNTING
1397	bool "Paravirtual steal time accounting"
1398	select PARAVIRT
1399	help
1400	  Select this option to enable fine granularity task steal time
1401	  accounting. Time spent executing other tasks in parallel with
1402	  the current vCPU is discounted from the vCPU power. To account for
1403	  that, there can be a small performance impact.
1404
1405	  If in doubt, say N here.
1406
1407config KEXEC
1408	depends on PM_SLEEP_SMP
1409	select KEXEC_CORE
1410	bool "kexec system call"
1411	help
1412	  kexec is a system call that implements the ability to shutdown your
1413	  current kernel, and to start another kernel.  It is like a reboot
1414	  but it is independent of the system firmware.   And like a reboot
1415	  you can start any kernel with it, not just Linux.
1416
1417config KEXEC_FILE
1418	bool "kexec file based system call"
1419	select KEXEC_CORE
1420	select HAVE_IMA_KEXEC if IMA
1421	help
1422	  This is new version of kexec system call. This system call is
1423	  file based and takes file descriptors as system call argument
1424	  for kernel and initramfs as opposed to list of segments as
1425	  accepted by previous system call.
1426
1427config KEXEC_SIG
1428	bool "Verify kernel signature during kexec_file_load() syscall"
1429	depends on KEXEC_FILE
1430	help
1431	  Select this option to verify a signature with loaded kernel
1432	  image. If configured, any attempt of loading a image without
1433	  valid signature will fail.
1434
1435	  In addition to that option, you need to enable signature
1436	  verification for the corresponding kernel image type being
1437	  loaded in order for this to work.
1438
1439config KEXEC_IMAGE_VERIFY_SIG
1440	bool "Enable Image signature verification support"
1441	default y
1442	depends on KEXEC_SIG
1443	depends on EFI && SIGNED_PE_FILE_VERIFICATION
1444	help
1445	  Enable Image signature verification support.
1446
1447comment "Support for PE file signature verification disabled"
1448	depends on KEXEC_SIG
1449	depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
1450
1451config CRASH_DUMP
1452	bool "Build kdump crash kernel"
1453	help
1454	  Generate crash dump after being started by kexec. This should
1455	  be normally only set in special crash dump kernels which are
1456	  loaded in the main kernel with kexec-tools into a specially
1457	  reserved region and then later executed after a crash by
1458	  kdump/kexec.
1459
1460	  For more details see Documentation/admin-guide/kdump/kdump.rst
1461
1462config TRANS_TABLE
1463	def_bool y
1464	depends on HIBERNATION || KEXEC_CORE
1465
1466config XEN_DOM0
1467	def_bool y
1468	depends on XEN
1469
1470config XEN
1471	bool "Xen guest support on ARM64"
1472	depends on ARM64 && OF
1473	select SWIOTLB_XEN
1474	select PARAVIRT
1475	help
1476	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1477
1478# include/linux/mmzone.h requires the following to be true:
1479#
1480#   MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1481#
1482# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1483#
1484#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_ORDER  |  default MAX_ORDER |
1485# ----+-------------------+--------------+-----------------+--------------------+
1486# 4K  |       27          |      12      |       15        |         10         |
1487# 16K |       27          |      14      |       13        |         11         |
1488# 64K |       29          |      16      |       13        |         13         |
1489config ARCH_FORCE_MAX_ORDER
1490	int "Order of maximal physically contiguous allocations" if EXPERT && (ARM64_4K_PAGES || ARM64_16K_PAGES)
1491	default "13" if ARM64_64K_PAGES
1492	default "11" if ARM64_16K_PAGES
1493	default "10"
1494	help
1495	  The kernel page allocator limits the size of maximal physically
1496	  contiguous allocations. The limit is called MAX_ORDER and it
1497	  defines the maximal power of two of number of pages that can be
1498	  allocated as a single contiguous block. This option allows
1499	  overriding the default setting when ability to allocate very
1500	  large blocks of physically contiguous memory is required.
1501
1502	  The maximal size of allocation cannot exceed the size of the
1503	  section, so the value of MAX_ORDER should satisfy
1504
1505	    MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1506
1507	  Don't change if unsure.
1508
1509config UNMAP_KERNEL_AT_EL0
1510	bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
1511	default y
1512	help
1513	  Speculation attacks against some high-performance processors can
1514	  be used to bypass MMU permission checks and leak kernel data to
1515	  userspace. This can be defended against by unmapping the kernel
1516	  when running in userspace, mapping it back in on exception entry
1517	  via a trampoline page in the vector table.
1518
1519	  If unsure, say Y.
1520
1521config MITIGATE_SPECTRE_BRANCH_HISTORY
1522	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1523	default y
1524	help
1525	  Speculation attacks against some high-performance processors can
1526	  make use of branch history to influence future speculation.
1527	  When taking an exception from user-space, a sequence of branches
1528	  or a firmware call overwrites the branch history.
1529
1530config RODATA_FULL_DEFAULT_ENABLED
1531	bool "Apply r/o permissions of VM areas also to their linear aliases"
1532	default y
1533	help
1534	  Apply read-only attributes of VM areas to the linear alias of
1535	  the backing pages as well. This prevents code or read-only data
1536	  from being modified (inadvertently or intentionally) via another
1537	  mapping of the same memory page. This additional enhancement can
1538	  be turned off at runtime by passing rodata=[off|on] (and turned on
1539	  with rodata=full if this option is set to 'n')
1540
1541	  This requires the linear region to be mapped down to pages,
1542	  which may adversely affect performance in some cases.
1543
1544config ARM64_SW_TTBR0_PAN
1545	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1546	help
1547	  Enabling this option prevents the kernel from accessing
1548	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1549	  zeroed area and reserved ASID. The user access routines
1550	  restore the valid TTBR0_EL1 temporarily.
1551
1552config ARM64_TAGGED_ADDR_ABI
1553	bool "Enable the tagged user addresses syscall ABI"
1554	default y
1555	help
1556	  When this option is enabled, user applications can opt in to a
1557	  relaxed ABI via prctl() allowing tagged addresses to be passed
1558	  to system calls as pointer arguments. For details, see
1559	  Documentation/arm64/tagged-address-abi.rst.
1560
1561menuconfig COMPAT
1562	bool "Kernel support for 32-bit EL0"
1563	depends on ARM64_4K_PAGES || EXPERT
1564	select HAVE_UID16
1565	select OLD_SIGSUSPEND3
1566	select COMPAT_OLD_SIGACTION
1567	help
1568	  This option enables support for a 32-bit EL0 running under a 64-bit
1569	  kernel at EL1. AArch32-specific components such as system calls,
1570	  the user helper functions, VFP support and the ptrace interface are
1571	  handled appropriately by the kernel.
1572
1573	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1574	  that you will only be able to execute AArch32 binaries that were compiled
1575	  with page size aligned segments.
1576
1577	  If you want to execute 32-bit userspace applications, say Y.
1578
1579if COMPAT
1580
1581config KUSER_HELPERS
1582	bool "Enable kuser helpers page for 32-bit applications"
1583	default y
1584	help
1585	  Warning: disabling this option may break 32-bit user programs.
1586
1587	  Provide kuser helpers to compat tasks. The kernel provides
1588	  helper code to userspace in read only form at a fixed location
1589	  to allow userspace to be independent of the CPU type fitted to
1590	  the system. This permits binaries to be run on ARMv4 through
1591	  to ARMv8 without modification.
1592
1593	  See Documentation/arm/kernel_user_helpers.rst for details.
1594
1595	  However, the fixed address nature of these helpers can be used
1596	  by ROP (return orientated programming) authors when creating
1597	  exploits.
1598
1599	  If all of the binaries and libraries which run on your platform
1600	  are built specifically for your platform, and make no use of
1601	  these helpers, then you can turn this option off to hinder
1602	  such exploits. However, in that case, if a binary or library
1603	  relying on those helpers is run, it will not function correctly.
1604
1605	  Say N here only if you are absolutely certain that you do not
1606	  need these helpers; otherwise, the safe option is to say Y.
1607
1608config COMPAT_VDSO
1609	bool "Enable vDSO for 32-bit applications"
1610	depends on !CPU_BIG_ENDIAN
1611	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1612	select GENERIC_COMPAT_VDSO
1613	default y
1614	help
1615	  Place in the process address space of 32-bit applications an
1616	  ELF shared object providing fast implementations of gettimeofday
1617	  and clock_gettime.
1618
1619	  You must have a 32-bit build of glibc 2.22 or later for programs
1620	  to seamlessly take advantage of this.
1621
1622config THUMB2_COMPAT_VDSO
1623	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1624	depends on COMPAT_VDSO
1625	default y
1626	help
1627	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1628	  otherwise with '-marm'.
1629
1630config COMPAT_ALIGNMENT_FIXUPS
1631	bool "Fix up misaligned multi-word loads and stores in user space"
1632
1633menuconfig ARMV8_DEPRECATED
1634	bool "Emulate deprecated/obsolete ARMv8 instructions"
1635	depends on SYSCTL
1636	help
1637	  Legacy software support may require certain instructions
1638	  that have been deprecated or obsoleted in the architecture.
1639
1640	  Enable this config to enable selective emulation of these
1641	  features.
1642
1643	  If unsure, say Y
1644
1645if ARMV8_DEPRECATED
1646
1647config SWP_EMULATION
1648	bool "Emulate SWP/SWPB instructions"
1649	help
1650	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1651	  they are always undefined. Say Y here to enable software
1652	  emulation of these instructions for userspace using LDXR/STXR.
1653	  This feature can be controlled at runtime with the abi.swp
1654	  sysctl which is disabled by default.
1655
1656	  In some older versions of glibc [<=2.8] SWP is used during futex
1657	  trylock() operations with the assumption that the code will not
1658	  be preempted. This invalid assumption may be more likely to fail
1659	  with SWP emulation enabled, leading to deadlock of the user
1660	  application.
1661
1662	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1663	  on an external transaction monitoring block called a global
1664	  monitor to maintain update atomicity. If your system does not
1665	  implement a global monitor, this option can cause programs that
1666	  perform SWP operations to uncached memory to deadlock.
1667
1668	  If unsure, say Y
1669
1670config CP15_BARRIER_EMULATION
1671	bool "Emulate CP15 Barrier instructions"
1672	help
1673	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1674	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1675	  strongly recommended to use the ISB, DSB, and DMB
1676	  instructions instead.
1677
1678	  Say Y here to enable software emulation of these
1679	  instructions for AArch32 userspace code. When this option is
1680	  enabled, CP15 barrier usage is traced which can help
1681	  identify software that needs updating. This feature can be
1682	  controlled at runtime with the abi.cp15_barrier sysctl.
1683
1684	  If unsure, say Y
1685
1686config SETEND_EMULATION
1687	bool "Emulate SETEND instruction"
1688	help
1689	  The SETEND instruction alters the data-endianness of the
1690	  AArch32 EL0, and is deprecated in ARMv8.
1691
1692	  Say Y here to enable software emulation of the instruction
1693	  for AArch32 userspace code. This feature can be controlled
1694	  at runtime with the abi.setend sysctl.
1695
1696	  Note: All the cpus on the system must have mixed endian support at EL0
1697	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1698	  endian - is hotplugged in after this feature has been enabled, there could
1699	  be unexpected results in the applications.
1700
1701	  If unsure, say Y
1702endif # ARMV8_DEPRECATED
1703
1704endif # COMPAT
1705
1706menu "ARMv8.1 architectural features"
1707
1708config ARM64_HW_AFDBM
1709	bool "Support for hardware updates of the Access and Dirty page flags"
1710	default y
1711	help
1712	  The ARMv8.1 architecture extensions introduce support for
1713	  hardware updates of the access and dirty information in page
1714	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1715	  capable processors, accesses to pages with PTE_AF cleared will
1716	  set this bit instead of raising an access flag fault.
1717	  Similarly, writes to read-only pages with the DBM bit set will
1718	  clear the read-only bit (AP[2]) instead of raising a
1719	  permission fault.
1720
1721	  Kernels built with this configuration option enabled continue
1722	  to work on pre-ARMv8.1 hardware and the performance impact is
1723	  minimal. If unsure, say Y.
1724
1725config ARM64_PAN
1726	bool "Enable support for Privileged Access Never (PAN)"
1727	default y
1728	help
1729	  Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1730	  prevents the kernel or hypervisor from accessing user-space (EL0)
1731	  memory directly.
1732
1733	  Choosing this option will cause any unprotected (not using
1734	  copy_to_user et al) memory access to fail with a permission fault.
1735
1736	  The feature is detected at runtime, and will remain as a 'nop'
1737	  instruction if the cpu does not implement the feature.
1738
1739config AS_HAS_LDAPR
1740	def_bool $(as-instr,.arch_extension rcpc)
1741
1742config AS_HAS_LSE_ATOMICS
1743	def_bool $(as-instr,.arch_extension lse)
1744
1745config ARM64_LSE_ATOMICS
1746	bool
1747	default ARM64_USE_LSE_ATOMICS
1748	depends on AS_HAS_LSE_ATOMICS
1749
1750config ARM64_USE_LSE_ATOMICS
1751	bool "Atomic instructions"
1752	default y
1753	help
1754	  As part of the Large System Extensions, ARMv8.1 introduces new
1755	  atomic instructions that are designed specifically to scale in
1756	  very large systems.
1757
1758	  Say Y here to make use of these instructions for the in-kernel
1759	  atomic routines. This incurs a small overhead on CPUs that do
1760	  not support these instructions and requires the kernel to be
1761	  built with binutils >= 2.25 in order for the new instructions
1762	  to be used.
1763
1764endmenu # "ARMv8.1 architectural features"
1765
1766menu "ARMv8.2 architectural features"
1767
1768config AS_HAS_ARMV8_2
1769	def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a)
1770
1771config AS_HAS_SHA3
1772	def_bool $(as-instr,.arch armv8.2-a+sha3)
1773
1774config ARM64_PMEM
1775	bool "Enable support for persistent memory"
1776	select ARCH_HAS_PMEM_API
1777	select ARCH_HAS_UACCESS_FLUSHCACHE
1778	help
1779	  Say Y to enable support for the persistent memory API based on the
1780	  ARMv8.2 DCPoP feature.
1781
1782	  The feature is detected at runtime, and the kernel will use DC CVAC
1783	  operations if DC CVAP is not supported (following the behaviour of
1784	  DC CVAP itself if the system does not define a point of persistence).
1785
1786config ARM64_RAS_EXTN
1787	bool "Enable support for RAS CPU Extensions"
1788	default y
1789	help
1790	  CPUs that support the Reliability, Availability and Serviceability
1791	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1792	  errors, classify them and report them to software.
1793
1794	  On CPUs with these extensions system software can use additional
1795	  barriers to determine if faults are pending and read the
1796	  classification from a new set of registers.
1797
1798	  Selecting this feature will allow the kernel to use these barriers
1799	  and access the new registers if the system supports the extension.
1800	  Platform RAS features may additionally depend on firmware support.
1801
1802config ARM64_CNP
1803	bool "Enable support for Common Not Private (CNP) translations"
1804	default y
1805	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1806	help
1807	  Common Not Private (CNP) allows translation table entries to
1808	  be shared between different PEs in the same inner shareable
1809	  domain, so the hardware can use this fact to optimise the
1810	  caching of such entries in the TLB.
1811
1812	  Selecting this option allows the CNP feature to be detected
1813	  at runtime, and does not affect PEs that do not implement
1814	  this feature.
1815
1816endmenu # "ARMv8.2 architectural features"
1817
1818menu "ARMv8.3 architectural features"
1819
1820config ARM64_PTR_AUTH
1821	bool "Enable support for pointer authentication"
1822	default y
1823	help
1824	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1825	  instructions for signing and authenticating pointers against secret
1826	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1827	  and other attacks.
1828
1829	  This option enables these instructions at EL0 (i.e. for userspace).
1830	  Choosing this option will cause the kernel to initialise secret keys
1831	  for each process at exec() time, with these keys being
1832	  context-switched along with the process.
1833
1834	  The feature is detected at runtime. If the feature is not present in
1835	  hardware it will not be advertised to userspace/KVM guest nor will it
1836	  be enabled.
1837
1838	  If the feature is present on the boot CPU but not on a late CPU, then
1839	  the late CPU will be parked. Also, if the boot CPU does not have
1840	  address auth and the late CPU has then the late CPU will still boot
1841	  but with the feature disabled. On such a system, this option should
1842	  not be selected.
1843
1844config ARM64_PTR_AUTH_KERNEL
1845	bool "Use pointer authentication for kernel"
1846	default y
1847	depends on ARM64_PTR_AUTH
1848	depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_ARMV8_3
1849	# Modern compilers insert a .note.gnu.property section note for PAC
1850	# which is only understood by binutils starting with version 2.33.1.
1851	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1852	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1853	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1854	help
1855	  If the compiler supports the -mbranch-protection or
1856	  -msign-return-address flag (e.g. GCC 7 or later), then this option
1857	  will cause the kernel itself to be compiled with return address
1858	  protection. In this case, and if the target hardware is known to
1859	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
1860	  disabled with minimal loss of protection.
1861
1862	  This feature works with FUNCTION_GRAPH_TRACER option only if
1863	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
1864
1865config CC_HAS_BRANCH_PROT_PAC_RET
1866	# GCC 9 or later, clang 8 or later
1867	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1868
1869config CC_HAS_SIGN_RETURN_ADDRESS
1870	# GCC 7, 8
1871	def_bool $(cc-option,-msign-return-address=all)
1872
1873config AS_HAS_ARMV8_3
1874	def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
1875
1876config AS_HAS_CFI_NEGATE_RA_STATE
1877	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1878
1879endmenu # "ARMv8.3 architectural features"
1880
1881menu "ARMv8.4 architectural features"
1882
1883config ARM64_AMU_EXTN
1884	bool "Enable support for the Activity Monitors Unit CPU extension"
1885	default y
1886	help
1887	  The activity monitors extension is an optional extension introduced
1888	  by the ARMv8.4 CPU architecture. This enables support for version 1
1889	  of the activity monitors architecture, AMUv1.
1890
1891	  To enable the use of this extension on CPUs that implement it, say Y.
1892
1893	  Note that for architectural reasons, firmware _must_ implement AMU
1894	  support when running on CPUs that present the activity monitors
1895	  extension. The required support is present in:
1896	    * Version 1.5 and later of the ARM Trusted Firmware
1897
1898	  For kernels that have this configuration enabled but boot with broken
1899	  firmware, you may need to say N here until the firmware is fixed.
1900	  Otherwise you may experience firmware panics or lockups when
1901	  accessing the counter registers. Even if you are not observing these
1902	  symptoms, the values returned by the register reads might not
1903	  correctly reflect reality. Most commonly, the value read will be 0,
1904	  indicating that the counter is not enabled.
1905
1906config AS_HAS_ARMV8_4
1907	def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
1908
1909config ARM64_TLB_RANGE
1910	bool "Enable support for tlbi range feature"
1911	default y
1912	depends on AS_HAS_ARMV8_4
1913	help
1914	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
1915	  range of input addresses.
1916
1917	  The feature introduces new assembly instructions, and they were
1918	  support when binutils >= 2.30.
1919
1920endmenu # "ARMv8.4 architectural features"
1921
1922menu "ARMv8.5 architectural features"
1923
1924config AS_HAS_ARMV8_5
1925	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
1926
1927config ARM64_BTI
1928	bool "Branch Target Identification support"
1929	default y
1930	help
1931	  Branch Target Identification (part of the ARMv8.5 Extensions)
1932	  provides a mechanism to limit the set of locations to which computed
1933	  branch instructions such as BR or BLR can jump.
1934
1935	  To make use of BTI on CPUs that support it, say Y.
1936
1937	  BTI is intended to provide complementary protection to other control
1938	  flow integrity protection mechanisms, such as the Pointer
1939	  authentication mechanism provided as part of the ARMv8.3 Extensions.
1940	  For this reason, it does not make sense to enable this option without
1941	  also enabling support for pointer authentication.  Thus, when
1942	  enabling this option you should also select ARM64_PTR_AUTH=y.
1943
1944	  Userspace binaries must also be specifically compiled to make use of
1945	  this mechanism.  If you say N here or the hardware does not support
1946	  BTI, such binaries can still run, but you get no additional
1947	  enforcement of branch destinations.
1948
1949config ARM64_BTI_KERNEL
1950	bool "Use Branch Target Identification for kernel"
1951	default y
1952	depends on ARM64_BTI
1953	depends on ARM64_PTR_AUTH_KERNEL
1954	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
1955	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
1956	depends on !CC_IS_GCC || GCC_VERSION >= 100100
1957	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
1958	depends on !CC_IS_GCC
1959	# https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9
1960	depends on !CC_IS_CLANG || CLANG_VERSION >= 120000
1961	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1962	help
1963	  Build the kernel with Branch Target Identification annotations
1964	  and enable enforcement of this for kernel code. When this option
1965	  is enabled and the system supports BTI all kernel code including
1966	  modular code must have BTI enabled.
1967
1968config CC_HAS_BRANCH_PROT_PAC_RET_BTI
1969	# GCC 9 or later, clang 8 or later
1970	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
1971
1972config ARM64_E0PD
1973	bool "Enable support for E0PD"
1974	default y
1975	help
1976	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
1977	  that EL0 accesses made via TTBR1 always fault in constant time,
1978	  providing similar benefits to KASLR as those provided by KPTI, but
1979	  with lower overhead and without disrupting legitimate access to
1980	  kernel memory such as SPE.
1981
1982	  This option enables E0PD for TTBR1 where available.
1983
1984config ARM64_AS_HAS_MTE
1985	# Initial support for MTE went in binutils 2.32.0, checked with
1986	# ".arch armv8.5-a+memtag" below. However, this was incomplete
1987	# as a late addition to the final architecture spec (LDGM/STGM)
1988	# is only supported in the newer 2.32.x and 2.33 binutils
1989	# versions, hence the extra "stgm" instruction check below.
1990	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
1991
1992config ARM64_MTE
1993	bool "Memory Tagging Extension support"
1994	default y
1995	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
1996	depends on AS_HAS_ARMV8_5
1997	depends on AS_HAS_LSE_ATOMICS
1998	# Required for tag checking in the uaccess routines
1999	depends on ARM64_PAN
2000	select ARCH_HAS_SUBPAGE_FAULTS
2001	select ARCH_USES_HIGH_VMA_FLAGS
2002	select ARCH_USES_PG_ARCH_X
2003	help
2004	  Memory Tagging (part of the ARMv8.5 Extensions) provides
2005	  architectural support for run-time, always-on detection of
2006	  various classes of memory error to aid with software debugging
2007	  to eliminate vulnerabilities arising from memory-unsafe
2008	  languages.
2009
2010	  This option enables the support for the Memory Tagging
2011	  Extension at EL0 (i.e. for userspace).
2012
2013	  Selecting this option allows the feature to be detected at
2014	  runtime. Any secondary CPU not implementing this feature will
2015	  not be allowed a late bring-up.
2016
2017	  Userspace binaries that want to use this feature must
2018	  explicitly opt in. The mechanism for the userspace is
2019	  described in:
2020
2021	  Documentation/arm64/memory-tagging-extension.rst.
2022
2023endmenu # "ARMv8.5 architectural features"
2024
2025menu "ARMv8.7 architectural features"
2026
2027config ARM64_EPAN
2028	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2029	default y
2030	depends on ARM64_PAN
2031	help
2032	  Enhanced Privileged Access Never (EPAN) allows Privileged
2033	  Access Never to be used with Execute-only mappings.
2034
2035	  The feature is detected at runtime, and will remain disabled
2036	  if the cpu does not implement the feature.
2037endmenu # "ARMv8.7 architectural features"
2038
2039config ARM64_SVE
2040	bool "ARM Scalable Vector Extension support"
2041	default y
2042	help
2043	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2044	  execution state which complements and extends the SIMD functionality
2045	  of the base architecture to support much larger vectors and to enable
2046	  additional vectorisation opportunities.
2047
2048	  To enable use of this extension on CPUs that implement it, say Y.
2049
2050	  On CPUs that support the SVE2 extensions, this option will enable
2051	  those too.
2052
2053	  Note that for architectural reasons, firmware _must_ implement SVE
2054	  support when running on SVE capable hardware.  The required support
2055	  is present in:
2056
2057	    * version 1.5 and later of the ARM Trusted Firmware
2058	    * the AArch64 boot wrapper since commit 5e1261e08abf
2059	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2060
2061	  For other firmware implementations, consult the firmware documentation
2062	  or vendor.
2063
2064	  If you need the kernel to boot on SVE-capable hardware with broken
2065	  firmware, you may need to say N here until you get your firmware
2066	  fixed.  Otherwise, you may experience firmware panics or lockups when
2067	  booting the kernel.  If unsure and you are not observing these
2068	  symptoms, you should assume that it is safe to say Y.
2069
2070config ARM64_SME
2071	bool "ARM Scalable Matrix Extension support"
2072	default y
2073	depends on ARM64_SVE
2074	help
2075	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2076	  execution state which utilises a substantial subset of the SVE
2077	  instruction set, together with the addition of new architectural
2078	  register state capable of holding two dimensional matrix tiles to
2079	  enable various matrix operations.
2080
2081config ARM64_MODULE_PLTS
2082	bool "Use PLTs to allow module memory to spill over into vmalloc area"
2083	depends on MODULES
2084	select HAVE_MOD_ARCH_SPECIFIC
2085	help
2086	  Allocate PLTs when loading modules so that jumps and calls whose
2087	  targets are too far away for their relative offsets to be encoded
2088	  in the instructions themselves can be bounced via veneers in the
2089	  module's PLT. This allows modules to be allocated in the generic
2090	  vmalloc area after the dedicated module memory area has been
2091	  exhausted.
2092
2093	  When running with address space randomization (KASLR), the module
2094	  region itself may be too far away for ordinary relative jumps and
2095	  calls, and so in that case, module PLTs are required and cannot be
2096	  disabled.
2097
2098	  Specific errata workaround(s) might also force module PLTs to be
2099	  enabled (ARM64_ERRATUM_843419).
2100
2101config ARM64_PSEUDO_NMI
2102	bool "Support for NMI-like interrupts"
2103	select ARM_GIC_V3
2104	help
2105	  Adds support for mimicking Non-Maskable Interrupts through the use of
2106	  GIC interrupt priority. This support requires version 3 or later of
2107	  ARM GIC.
2108
2109	  This high priority configuration for interrupts needs to be
2110	  explicitly enabled by setting the kernel parameter
2111	  "irqchip.gicv3_pseudo_nmi" to 1.
2112
2113	  If unsure, say N
2114
2115if ARM64_PSEUDO_NMI
2116config ARM64_DEBUG_PRIORITY_MASKING
2117	bool "Debug interrupt priority masking"
2118	help
2119	  This adds runtime checks to functions enabling/disabling
2120	  interrupts when using priority masking. The additional checks verify
2121	  the validity of ICC_PMR_EL1 when calling concerned functions.
2122
2123	  If unsure, say N
2124endif # ARM64_PSEUDO_NMI
2125
2126config RELOCATABLE
2127	bool "Build a relocatable kernel image" if EXPERT
2128	select ARCH_HAS_RELR
2129	default y
2130	help
2131	  This builds the kernel as a Position Independent Executable (PIE),
2132	  which retains all relocation metadata required to relocate the
2133	  kernel binary at runtime to a different virtual address than the
2134	  address it was linked at.
2135	  Since AArch64 uses the RELA relocation format, this requires a
2136	  relocation pass at runtime even if the kernel is loaded at the
2137	  same address it was linked at.
2138
2139config RANDOMIZE_BASE
2140	bool "Randomize the address of the kernel image"
2141	select ARM64_MODULE_PLTS if MODULES
2142	select RELOCATABLE
2143	help
2144	  Randomizes the virtual address at which the kernel image is
2145	  loaded, as a security feature that deters exploit attempts
2146	  relying on knowledge of the location of kernel internals.
2147
2148	  It is the bootloader's job to provide entropy, by passing a
2149	  random u64 value in /chosen/kaslr-seed at kernel entry.
2150
2151	  When booting via the UEFI stub, it will invoke the firmware's
2152	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2153	  to the kernel proper. In addition, it will randomise the physical
2154	  location of the kernel Image as well.
2155
2156	  If unsure, say N.
2157
2158config RANDOMIZE_MODULE_REGION_FULL
2159	bool "Randomize the module region over a 2 GB range"
2160	depends on RANDOMIZE_BASE
2161	default y
2162	help
2163	  Randomizes the location of the module region inside a 2 GB window
2164	  covering the core kernel. This way, it is less likely for modules
2165	  to leak information about the location of core kernel data structures
2166	  but it does imply that function calls between modules and the core
2167	  kernel will need to be resolved via veneers in the module PLT.
2168
2169	  When this option is not set, the module region will be randomized over
2170	  a limited range that contains the [_stext, _etext] interval of the
2171	  core kernel, so branch relocations are almost always in range unless
2172	  ARM64_MODULE_PLTS is enabled and the region is exhausted. In this
2173	  particular case of region exhaustion, modules might be able to fall
2174	  back to a larger 2GB area.
2175
2176config CC_HAVE_STACKPROTECTOR_SYSREG
2177	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2178
2179config STACKPROTECTOR_PER_TASK
2180	def_bool y
2181	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2182
2183config UNWIND_PATCH_PAC_INTO_SCS
2184	bool "Enable shadow call stack dynamically using code patching"
2185	# needs Clang with https://reviews.llvm.org/D111780 incorporated
2186	depends on CC_IS_CLANG && CLANG_VERSION >= 150000
2187	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2188	depends on SHADOW_CALL_STACK
2189	select UNWIND_TABLES
2190	select DYNAMIC_SCS
2191
2192endmenu # "Kernel Features"
2193
2194menu "Boot options"
2195
2196config ARM64_ACPI_PARKING_PROTOCOL
2197	bool "Enable support for the ARM64 ACPI parking protocol"
2198	depends on ACPI
2199	help
2200	  Enable support for the ARM64 ACPI parking protocol. If disabled
2201	  the kernel will not allow booting through the ARM64 ACPI parking
2202	  protocol even if the corresponding data is present in the ACPI
2203	  MADT table.
2204
2205config CMDLINE
2206	string "Default kernel command string"
2207	default ""
2208	help
2209	  Provide a set of default command-line options at build time by
2210	  entering them here. As a minimum, you should specify the the
2211	  root device (e.g. root=/dev/nfs).
2212
2213choice
2214	prompt "Kernel command line type" if CMDLINE != ""
2215	default CMDLINE_FROM_BOOTLOADER
2216	help
2217	  Choose how the kernel will handle the provided default kernel
2218	  command line string.
2219
2220config CMDLINE_FROM_BOOTLOADER
2221	bool "Use bootloader kernel arguments if available"
2222	help
2223	  Uses the command-line options passed by the boot loader. If
2224	  the boot loader doesn't provide any, the default kernel command
2225	  string provided in CMDLINE will be used.
2226
2227config CMDLINE_FORCE
2228	bool "Always use the default kernel command string"
2229	help
2230	  Always use the default kernel command string, even if the boot
2231	  loader passes other arguments to the kernel.
2232	  This is useful if you cannot or don't want to change the
2233	  command-line options your boot loader passes to the kernel.
2234
2235endchoice
2236
2237config EFI_STUB
2238	bool
2239
2240config EFI
2241	bool "UEFI runtime support"
2242	depends on OF && !CPU_BIG_ENDIAN
2243	depends on KERNEL_MODE_NEON
2244	select ARCH_SUPPORTS_ACPI
2245	select LIBFDT
2246	select UCS2_STRING
2247	select EFI_PARAMS_FROM_FDT
2248	select EFI_RUNTIME_WRAPPERS
2249	select EFI_STUB
2250	select EFI_GENERIC_STUB
2251	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2252	default y
2253	help
2254	  This option provides support for runtime services provided
2255	  by UEFI firmware (such as non-volatile variables, realtime
2256	  clock, and platform reset). A UEFI stub is also provided to
2257	  allow the kernel to be booted as an EFI application. This
2258	  is only useful on systems that have UEFI firmware.
2259
2260config DMI
2261	bool "Enable support for SMBIOS (DMI) tables"
2262	depends on EFI
2263	default y
2264	help
2265	  This enables SMBIOS/DMI feature for systems.
2266
2267	  This option is only useful on systems that have UEFI firmware.
2268	  However, even with this option, the resultant kernel should
2269	  continue to boot on existing non-UEFI platforms.
2270
2271endmenu # "Boot options"
2272
2273menu "Power management options"
2274
2275source "kernel/power/Kconfig"
2276
2277config ARCH_HIBERNATION_POSSIBLE
2278	def_bool y
2279	depends on CPU_PM
2280
2281config ARCH_HIBERNATION_HEADER
2282	def_bool y
2283	depends on HIBERNATION
2284
2285config ARCH_SUSPEND_POSSIBLE
2286	def_bool y
2287
2288endmenu # "Power management options"
2289
2290menu "CPU Power Management"
2291
2292source "drivers/cpuidle/Kconfig"
2293
2294source "drivers/cpufreq/Kconfig"
2295
2296endmenu # "CPU Power Management"
2297
2298source "drivers/acpi/Kconfig"
2299
2300source "arch/arm64/kvm/Kconfig"
2301
2302