xref: /openbmc/linux/arch/arm64/Kconfig (revision 6aeadf78)
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 HAS_IOPORT
150	select HAVE_MOVE_PMD
151	select HAVE_MOVE_PUD
152	select HAVE_PCI
153	select HAVE_ACPI_APEI if (ACPI && EFI)
154	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
155	select HAVE_ARCH_AUDITSYSCALL
156	select HAVE_ARCH_BITREVERSE
157	select HAVE_ARCH_COMPILER_H
158	select HAVE_ARCH_HUGE_VMALLOC
159	select HAVE_ARCH_HUGE_VMAP
160	select HAVE_ARCH_JUMP_LABEL
161	select HAVE_ARCH_JUMP_LABEL_RELATIVE
162	select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
163	select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
164	select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
165	select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
166	# Some instrumentation may be unsound, hence EXPERT
167	select HAVE_ARCH_KCSAN if EXPERT
168	select HAVE_ARCH_KFENCE
169	select HAVE_ARCH_KGDB
170	select HAVE_ARCH_MMAP_RND_BITS
171	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
172	select HAVE_ARCH_PREL32_RELOCATIONS
173	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
174	select HAVE_ARCH_SECCOMP_FILTER
175	select HAVE_ARCH_STACKLEAK
176	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
177	select HAVE_ARCH_TRACEHOOK
178	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
179	select HAVE_ARCH_VMAP_STACK
180	select HAVE_ARM_SMCCC
181	select HAVE_ASM_MODVERSIONS
182	select HAVE_EBPF_JIT
183	select HAVE_C_RECORDMCOUNT
184	select HAVE_CMPXCHG_DOUBLE
185	select HAVE_CMPXCHG_LOCAL
186	select HAVE_CONTEXT_TRACKING_USER
187	select HAVE_DEBUG_KMEMLEAK
188	select HAVE_DMA_CONTIGUOUS
189	select HAVE_DYNAMIC_FTRACE
190	select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
191		if $(cc-option,-fpatchable-function-entry=2)
192	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \
193		if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS
194	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
195		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG && \
196		    !CC_OPTIMIZE_FOR_SIZE)
197	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
198		if DYNAMIC_FTRACE_WITH_ARGS
199	select HAVE_EFFICIENT_UNALIGNED_ACCESS
200	select HAVE_FAST_GUP
201	select HAVE_FTRACE_MCOUNT_RECORD
202	select HAVE_FUNCTION_TRACER
203	select HAVE_FUNCTION_ERROR_INJECTION
204	select HAVE_FUNCTION_GRAPH_TRACER
205	select HAVE_GCC_PLUGINS
206	select HAVE_HW_BREAKPOINT if PERF_EVENTS
207	select HAVE_IOREMAP_PROT
208	select HAVE_IRQ_TIME_ACCOUNTING
209	select HAVE_KVM
210	select HAVE_MOD_ARCH_SPECIFIC
211	select HAVE_NMI
212	select HAVE_PERF_EVENTS
213	select HAVE_PERF_REGS
214	select HAVE_PERF_USER_STACK_DUMP
215	select HAVE_PREEMPT_DYNAMIC_KEY
216	select HAVE_REGS_AND_STACK_ACCESS_API
217	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
218	select HAVE_FUNCTION_ARG_ACCESS_API
219	select MMU_GATHER_RCU_TABLE_FREE
220	select HAVE_RSEQ
221	select HAVE_STACKPROTECTOR
222	select HAVE_SYSCALL_TRACEPOINTS
223	select HAVE_KPROBES
224	select HAVE_KRETPROBES
225	select HAVE_GENERIC_VDSO
226	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
227	select IRQ_DOMAIN
228	select IRQ_FORCED_THREADING
229	select KASAN_VMALLOC if KASAN
230	select MODULES_USE_ELF_RELA
231	select NEED_DMA_MAP_STATE
232	select NEED_SG_DMA_LENGTH
233	select OF
234	select OF_EARLY_FLATTREE
235	select PCI_DOMAINS_GENERIC if PCI
236	select PCI_ECAM if (ACPI && PCI)
237	select PCI_SYSCALL if PCI
238	select POWER_RESET
239	select POWER_SUPPLY
240	select SPARSE_IRQ
241	select SWIOTLB
242	select SYSCTL_EXCEPTION_TRACE
243	select THREAD_INFO_IN_TASK
244	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
245	select TRACE_IRQFLAGS_SUPPORT
246	select TRACE_IRQFLAGS_NMI_SUPPORT
247	select HAVE_SOFTIRQ_ON_OWN_STACK
248	help
249	  ARM 64-bit (AArch64) Linux support.
250
251config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
252	def_bool CC_IS_CLANG
253	# https://github.com/ClangBuiltLinux/linux/issues/1507
254	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
255	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
256
257config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
258	def_bool CC_IS_GCC
259	depends on $(cc-option,-fpatchable-function-entry=2)
260	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
261
262config 64BIT
263	def_bool y
264
265config MMU
266	def_bool y
267
268config ARM64_PAGE_SHIFT
269	int
270	default 16 if ARM64_64K_PAGES
271	default 14 if ARM64_16K_PAGES
272	default 12
273
274config ARM64_CONT_PTE_SHIFT
275	int
276	default 5 if ARM64_64K_PAGES
277	default 7 if ARM64_16K_PAGES
278	default 4
279
280config ARM64_CONT_PMD_SHIFT
281	int
282	default 5 if ARM64_64K_PAGES
283	default 5 if ARM64_16K_PAGES
284	default 4
285
286config ARCH_MMAP_RND_BITS_MIN
287	default 14 if ARM64_64K_PAGES
288	default 16 if ARM64_16K_PAGES
289	default 18
290
291# max bits determined by the following formula:
292#  VA_BITS - PAGE_SHIFT - 3
293config ARCH_MMAP_RND_BITS_MAX
294	default 19 if ARM64_VA_BITS=36
295	default 24 if ARM64_VA_BITS=39
296	default 27 if ARM64_VA_BITS=42
297	default 30 if ARM64_VA_BITS=47
298	default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
299	default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
300	default 33 if ARM64_VA_BITS=48
301	default 14 if ARM64_64K_PAGES
302	default 16 if ARM64_16K_PAGES
303	default 18
304
305config ARCH_MMAP_RND_COMPAT_BITS_MIN
306	default 7 if ARM64_64K_PAGES
307	default 9 if ARM64_16K_PAGES
308	default 11
309
310config ARCH_MMAP_RND_COMPAT_BITS_MAX
311	default 16
312
313config NO_IOPORT_MAP
314	def_bool y if !PCI
315
316config STACKTRACE_SUPPORT
317	def_bool y
318
319config ILLEGAL_POINTER_VALUE
320	hex
321	default 0xdead000000000000
322
323config LOCKDEP_SUPPORT
324	def_bool y
325
326config GENERIC_BUG
327	def_bool y
328	depends on BUG
329
330config GENERIC_BUG_RELATIVE_POINTERS
331	def_bool y
332	depends on GENERIC_BUG
333
334config GENERIC_HWEIGHT
335	def_bool y
336
337config GENERIC_CSUM
338	def_bool y
339
340config GENERIC_CALIBRATE_DELAY
341	def_bool y
342
343config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
344	def_bool y
345
346config SMP
347	def_bool y
348
349config KERNEL_MODE_NEON
350	def_bool y
351
352config FIX_EARLYCON_MEM
353	def_bool y
354
355config PGTABLE_LEVELS
356	int
357	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
358	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
359	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
360	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
361	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
362	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
363
364config ARCH_SUPPORTS_UPROBES
365	def_bool y
366
367config ARCH_PROC_KCORE_TEXT
368	def_bool y
369
370config BROKEN_GAS_INST
371	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
372
373config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
374	bool
375	# Clang's __builtin_return_adddress() strips the PAC since 12.0.0
376	# https://reviews.llvm.org/D75044
377	default y if CC_IS_CLANG && (CLANG_VERSION >= 120000)
378	# GCC's __builtin_return_address() strips the PAC since 11.1.0,
379	# and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier
380	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891
381	default y if CC_IS_GCC && (GCC_VERSION >= 110100)
382	default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000)
383	default y if CC_IS_GCC && (GCC_VERSION >=  90400) && (GCC_VERSION < 100000)
384	default y if CC_IS_GCC && (GCC_VERSION >=  80500) && (GCC_VERSION <  90000)
385	default n
386
387config KASAN_SHADOW_OFFSET
388	hex
389	depends on KASAN_GENERIC || KASAN_SW_TAGS
390	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
391	default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
392	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
393	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
394	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
395	default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
396	default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
397	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
398	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
399	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
400	default 0xffffffffffffffff
401
402config UNWIND_TABLES
403	bool
404
405source "arch/arm64/Kconfig.platforms"
406
407menu "Kernel Features"
408
409menu "ARM errata workarounds via the alternatives framework"
410
411config ARM64_WORKAROUND_CLEAN_CACHE
412	bool
413
414config ARM64_ERRATUM_826319
415	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
416	default y
417	select ARM64_WORKAROUND_CLEAN_CACHE
418	help
419	  This option adds an alternative code sequence to work around ARM
420	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
421	  AXI master interface and an L2 cache.
422
423	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
424	  and is unable to accept a certain write via this interface, it will
425	  not progress on read data presented on the read data channel and the
426	  system can deadlock.
427
428	  The workaround promotes data cache clean instructions to
429	  data cache clean-and-invalidate.
430	  Please note that this does not necessarily enable the workaround,
431	  as it depends on the alternative framework, which will only patch
432	  the kernel if an affected CPU is detected.
433
434	  If unsure, say Y.
435
436config ARM64_ERRATUM_827319
437	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
438	default y
439	select ARM64_WORKAROUND_CLEAN_CACHE
440	help
441	  This option adds an alternative code sequence to work around ARM
442	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
443	  master interface and an L2 cache.
444
445	  Under certain conditions this erratum can cause a clean line eviction
446	  to occur at the same time as another transaction to the same address
447	  on the AMBA 5 CHI interface, which can cause data corruption if the
448	  interconnect reorders the two transactions.
449
450	  The workaround promotes data cache clean instructions to
451	  data cache clean-and-invalidate.
452	  Please note that this does not necessarily enable the workaround,
453	  as it depends on the alternative framework, which will only patch
454	  the kernel if an affected CPU is detected.
455
456	  If unsure, say Y.
457
458config ARM64_ERRATUM_824069
459	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
460	default y
461	select ARM64_WORKAROUND_CLEAN_CACHE
462	help
463	  This option adds an alternative code sequence to work around ARM
464	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
465	  to a coherent interconnect.
466
467	  If a Cortex-A53 processor is executing a store or prefetch for
468	  write instruction at the same time as a processor in another
469	  cluster is executing a cache maintenance operation to the same
470	  address, then this erratum might cause a clean cache line to be
471	  incorrectly marked as dirty.
472
473	  The workaround promotes data cache clean instructions to
474	  data cache clean-and-invalidate.
475	  Please note that this option does not necessarily enable the
476	  workaround, as it depends on the alternative framework, which will
477	  only patch the kernel if an affected CPU is detected.
478
479	  If unsure, say Y.
480
481config ARM64_ERRATUM_819472
482	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
483	default y
484	select ARM64_WORKAROUND_CLEAN_CACHE
485	help
486	  This option adds an alternative code sequence to work around ARM
487	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
488	  present when it is connected to a coherent interconnect.
489
490	  If the processor is executing a load and store exclusive sequence at
491	  the same time as a processor in another cluster is executing a cache
492	  maintenance operation to the same address, then this erratum might
493	  cause data corruption.
494
495	  The workaround promotes data cache clean instructions to
496	  data cache clean-and-invalidate.
497	  Please note that this does not necessarily enable the workaround,
498	  as it depends on the alternative framework, which will only patch
499	  the kernel if an affected CPU is detected.
500
501	  If unsure, say Y.
502
503config ARM64_ERRATUM_832075
504	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
505	default y
506	help
507	  This option adds an alternative code sequence to work around ARM
508	  erratum 832075 on Cortex-A57 parts up to r1p2.
509
510	  Affected Cortex-A57 parts might deadlock when exclusive load/store
511	  instructions to Write-Back memory are mixed with Device loads.
512
513	  The workaround is to promote device loads to use Load-Acquire
514	  semantics.
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_834220
522	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
523	depends on KVM
524	default y
525	help
526	  This option adds an alternative code sequence to work around ARM
527	  erratum 834220 on Cortex-A57 parts up to r1p2.
528
529	  Affected Cortex-A57 parts might report a Stage 2 translation
530	  fault as the result of a Stage 1 fault for load crossing a
531	  page boundary when there is a permission or device memory
532	  alignment fault at Stage 1 and a translation fault at Stage 2.
533
534	  The workaround is to verify that the Stage 1 translation
535	  doesn't generate a fault before handling the Stage 2 fault.
536	  Please note that this does not necessarily enable the workaround,
537	  as it depends on the alternative framework, which will only patch
538	  the kernel if an affected CPU is detected.
539
540	  If unsure, say Y.
541
542config ARM64_ERRATUM_1742098
543	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
544	depends on COMPAT
545	default y
546	help
547	  This option removes the AES hwcap for aarch32 user-space to
548	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
549
550	  Affected parts may corrupt the AES state if an interrupt is
551	  taken between a pair of AES instructions. These instructions
552	  are only present if the cryptography extensions are present.
553	  All software should have a fallback implementation for CPUs
554	  that don't implement the cryptography extensions.
555
556	  If unsure, say Y.
557
558config ARM64_ERRATUM_845719
559	bool "Cortex-A53: 845719: a load might read incorrect data"
560	depends on COMPAT
561	default y
562	help
563	  This option adds an alternative code sequence to work around ARM
564	  erratum 845719 on Cortex-A53 parts up to r0p4.
565
566	  When running a compat (AArch32) userspace on an affected Cortex-A53
567	  part, a load at EL0 from a virtual address that matches the bottom 32
568	  bits of the virtual address used by a recent load at (AArch64) EL1
569	  might return incorrect data.
570
571	  The workaround is to write the contextidr_el1 register on exception
572	  return to a 32-bit task.
573	  Please note that this does not necessarily enable the workaround,
574	  as it depends on the alternative framework, which will only patch
575	  the kernel if an affected CPU is detected.
576
577	  If unsure, say Y.
578
579config ARM64_ERRATUM_843419
580	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
581	default y
582	help
583	  This option links the kernel with '--fix-cortex-a53-843419' and
584	  enables PLT support to replace certain ADRP instructions, which can
585	  cause subsequent memory accesses to use an incorrect address on
586	  Cortex-A53 parts up to r0p4.
587
588	  If unsure, say Y.
589
590config ARM64_LD_HAS_FIX_ERRATUM_843419
591	def_bool $(ld-option,--fix-cortex-a53-843419)
592
593config ARM64_ERRATUM_1024718
594	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
595	default y
596	help
597	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
598
599	  Affected Cortex-A55 cores (all revisions) could cause incorrect
600	  update of the hardware dirty bit when the DBM/AP bits are updated
601	  without a break-before-make. The workaround is to disable the usage
602	  of hardware DBM locally on the affected cores. CPUs not affected by
603	  this erratum will continue to use the feature.
604
605	  If unsure, say Y.
606
607config ARM64_ERRATUM_1418040
608	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
609	default y
610	depends on COMPAT
611	help
612	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
613	  errata 1188873 and 1418040.
614
615	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
616	  cause register corruption when accessing the timer registers
617	  from AArch32 userspace.
618
619	  If unsure, say Y.
620
621config ARM64_WORKAROUND_SPECULATIVE_AT
622	bool
623
624config ARM64_ERRATUM_1165522
625	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
626	default y
627	select ARM64_WORKAROUND_SPECULATIVE_AT
628	help
629	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
630
631	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
632	  corrupted TLBs by speculating an AT instruction during a guest
633	  context switch.
634
635	  If unsure, say Y.
636
637config ARM64_ERRATUM_1319367
638	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
639	default y
640	select ARM64_WORKAROUND_SPECULATIVE_AT
641	help
642	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
643	  and A72 erratum 1319367
644
645	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
646	  speculating an AT instruction during a guest context switch.
647
648	  If unsure, say Y.
649
650config ARM64_ERRATUM_1530923
651	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
652	default y
653	select ARM64_WORKAROUND_SPECULATIVE_AT
654	help
655	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
656
657	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
658	  corrupted TLBs by speculating an AT instruction during a guest
659	  context switch.
660
661	  If unsure, say Y.
662
663config ARM64_WORKAROUND_REPEAT_TLBI
664	bool
665
666config ARM64_ERRATUM_2441007
667	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
668	default y
669	select ARM64_WORKAROUND_REPEAT_TLBI
670	help
671	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
672
673	  Under very rare circumstances, affected Cortex-A55 CPUs
674	  may not handle a race between a break-before-make sequence on one
675	  CPU, and another CPU accessing the same page. This could allow a
676	  store to a page that has been unmapped.
677
678	  Work around this by adding the affected CPUs to the list that needs
679	  TLB sequences to be done twice.
680
681	  If unsure, say Y.
682
683config ARM64_ERRATUM_1286807
684	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
685	default y
686	select ARM64_WORKAROUND_REPEAT_TLBI
687	help
688	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
689
690	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
691	  address for a cacheable mapping of a location is being
692	  accessed by a core while another core is remapping the virtual
693	  address to a new physical page using the recommended
694	  break-before-make sequence, then under very rare circumstances
695	  TLBI+DSB completes before a read using the translation being
696	  invalidated has been observed by other observers. The
697	  workaround repeats the TLBI+DSB operation.
698
699config ARM64_ERRATUM_1463225
700	bool "Cortex-A76: Software Step might prevent interrupt recognition"
701	default y
702	help
703	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
704
705	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
706	  of a system call instruction (SVC) can prevent recognition of
707	  subsequent interrupts when software stepping is disabled in the
708	  exception handler of the system call and either kernel debugging
709	  is enabled or VHE is in use.
710
711	  Work around the erratum by triggering a dummy step exception
712	  when handling a system call from a task that is being stepped
713	  in a VHE configuration of the kernel.
714
715	  If unsure, say Y.
716
717config ARM64_ERRATUM_1542419
718	bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
719	default y
720	help
721	  This option adds a workaround for ARM Neoverse-N1 erratum
722	  1542419.
723
724	  Affected Neoverse-N1 cores could execute a stale instruction when
725	  modified by another CPU. The workaround depends on a firmware
726	  counterpart.
727
728	  Workaround the issue by hiding the DIC feature from EL0. This
729	  forces user-space to perform cache maintenance.
730
731	  If unsure, say Y.
732
733config ARM64_ERRATUM_1508412
734	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
735	default y
736	help
737	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
738
739	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
740	  of a store-exclusive or read of PAR_EL1 and a load with device or
741	  non-cacheable memory attributes. The workaround depends on a firmware
742	  counterpart.
743
744	  KVM guests must also have the workaround implemented or they can
745	  deadlock the system.
746
747	  Work around the issue by inserting DMB SY barriers around PAR_EL1
748	  register reads and warning KVM users. The DMB barrier is sufficient
749	  to prevent a speculative PAR_EL1 read.
750
751	  If unsure, say Y.
752
753config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
754	bool
755
756config ARM64_ERRATUM_2051678
757	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
758	default y
759	help
760	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
761	  Affected Cortex-A510 might not respect the ordering rules for
762	  hardware update of the page table's dirty bit. The workaround
763	  is to not enable the feature on affected CPUs.
764
765	  If unsure, say Y.
766
767config ARM64_ERRATUM_2077057
768	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
769	default y
770	help
771	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
772	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
773	  expected, but a Pointer Authentication trap is taken instead. The
774	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
775	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
776
777	  This can only happen when EL2 is stepping EL1.
778
779	  When these conditions occur, the SPSR_EL2 value is unchanged from the
780	  previous guest entry, and can be restored from the in-memory copy.
781
782	  If unsure, say Y.
783
784config ARM64_ERRATUM_2658417
785	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
786	default y
787	help
788	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
789	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
790	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
791	  A510 CPUs are using shared neon hardware. As the sharing is not
792	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
793	  user-space should not be using these instructions.
794
795	  If unsure, say Y.
796
797config ARM64_ERRATUM_2119858
798	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
799	default y
800	depends on CORESIGHT_TRBE
801	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
802	help
803	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
804
805	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
806	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
807	  the event of a WRAP event.
808
809	  Work around the issue by always making sure we move the TRBPTR_EL1 by
810	  256 bytes before enabling the buffer and filling the first 256 bytes of
811	  the buffer with ETM ignore packets upon disabling.
812
813	  If unsure, say Y.
814
815config ARM64_ERRATUM_2139208
816	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
817	default y
818	depends on CORESIGHT_TRBE
819	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
820	help
821	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
822
823	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
824	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
825	  the event of a WRAP event.
826
827	  Work around the issue by always making sure we move the TRBPTR_EL1 by
828	  256 bytes before enabling the buffer and filling the first 256 bytes of
829	  the buffer with ETM ignore packets upon disabling.
830
831	  If unsure, say Y.
832
833config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
834	bool
835
836config ARM64_ERRATUM_2054223
837	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
838	default y
839	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
840	help
841	  Enable workaround for ARM Cortex-A710 erratum 2054223
842
843	  Affected cores may fail to flush the trace data on a TSB instruction, when
844	  the PE is in trace prohibited state. This will cause losing a few bytes
845	  of the trace cached.
846
847	  Workaround is to issue two TSB consecutively on affected cores.
848
849	  If unsure, say Y.
850
851config ARM64_ERRATUM_2067961
852	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
853	default y
854	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
855	help
856	  Enable workaround for ARM Neoverse-N2 erratum 2067961
857
858	  Affected cores may fail to flush the trace data on a TSB instruction, when
859	  the PE is in trace prohibited state. This will cause losing a few bytes
860	  of the trace cached.
861
862	  Workaround is to issue two TSB consecutively on affected cores.
863
864	  If unsure, say Y.
865
866config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
867	bool
868
869config ARM64_ERRATUM_2253138
870	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
871	depends on CORESIGHT_TRBE
872	default y
873	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
874	help
875	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
876
877	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
878	  for TRBE. Under some conditions, the TRBE might generate a write to the next
879	  virtually addressed page following the last page of the TRBE address space
880	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
881
882	  Work around this in the driver by always making sure that there is a
883	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
884
885	  If unsure, say Y.
886
887config ARM64_ERRATUM_2224489
888	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
889	depends on CORESIGHT_TRBE
890	default y
891	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
892	help
893	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
894
895	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
896	  for TRBE. Under some conditions, the TRBE might generate a write to the next
897	  virtually addressed page following the last page of the TRBE address space
898	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
899
900	  Work around this in the driver by always making sure that there is a
901	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
902
903	  If unsure, say Y.
904
905config ARM64_ERRATUM_2441009
906	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
907	default y
908	select ARM64_WORKAROUND_REPEAT_TLBI
909	help
910	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
911
912	  Under very rare circumstances, affected Cortex-A510 CPUs
913	  may not handle a race between a break-before-make sequence on one
914	  CPU, and another CPU accessing the same page. This could allow a
915	  store to a page that has been unmapped.
916
917	  Work around this by adding the affected CPUs to the list that needs
918	  TLB sequences to be done twice.
919
920	  If unsure, say Y.
921
922config ARM64_ERRATUM_2064142
923	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
924	depends on CORESIGHT_TRBE
925	default y
926	help
927	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
928
929	  Affected Cortex-A510 core might fail to write into system registers after the
930	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
931	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
932	  and TRBTRG_EL1 will be ignored and will not be effected.
933
934	  Work around this in the driver by executing TSB CSYNC and DSB after collection
935	  is stopped and before performing a system register write to one of the affected
936	  registers.
937
938	  If unsure, say Y.
939
940config ARM64_ERRATUM_2038923
941	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
942	depends on CORESIGHT_TRBE
943	default y
944	help
945	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
946
947	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
948	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
949	  might be corrupted. This happens after TRBE buffer has been enabled by setting
950	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
951	  execution changes from a context, in which trace is prohibited to one where it
952	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
953	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
954	  the trace buffer state might be corrupted.
955
956	  Work around this in the driver by preventing an inconsistent view of whether the
957	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
958	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
959	  two ISB instructions if no ERET is to take place.
960
961	  If unsure, say Y.
962
963config ARM64_ERRATUM_1902691
964	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
965	depends on CORESIGHT_TRBE
966	default y
967	help
968	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
969
970	  Affected Cortex-A510 core might cause trace data corruption, when being written
971	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
972	  trace data.
973
974	  Work around this problem in the driver by just preventing TRBE initialization on
975	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
976	  on such implementations. This will cover the kernel for any firmware that doesn't
977	  do this already.
978
979	  If unsure, say Y.
980
981config ARM64_ERRATUM_2457168
982	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
983	depends on ARM64_AMU_EXTN
984	default y
985	help
986	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
987
988	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
989	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
990	  incorrectly giving a significantly higher output value.
991
992	  Work around this problem by returning 0 when reading the affected counter in
993	  key locations that results in disabling all users of this counter. This effect
994	  is the same to firmware disabling affected counters.
995
996	  If unsure, say Y.
997
998config ARM64_ERRATUM_2645198
999	bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1000	default y
1001	help
1002	  This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1003
1004	  If a Cortex-A715 cpu sees a page mapping permissions change from executable
1005	  to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1006	  next instruction abort caused by permission fault.
1007
1008	  Only user-space does executable to non-executable permission transition via
1009	  mprotect() system call. Workaround the problem by doing a break-before-make
1010	  TLB invalidation, for all changes to executable user space mappings.
1011
1012	  If unsure, say Y.
1013
1014config CAVIUM_ERRATUM_22375
1015	bool "Cavium erratum 22375, 24313"
1016	default y
1017	help
1018	  Enable workaround for errata 22375 and 24313.
1019
1020	  This implements two gicv3-its errata workarounds for ThunderX. Both
1021	  with a small impact affecting only ITS table allocation.
1022
1023	    erratum 22375: only alloc 8MB table size
1024	    erratum 24313: ignore memory access type
1025
1026	  The fixes are in ITS initialization and basically ignore memory access
1027	  type and table size provided by the TYPER and BASER registers.
1028
1029	  If unsure, say Y.
1030
1031config CAVIUM_ERRATUM_23144
1032	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1033	depends on NUMA
1034	default y
1035	help
1036	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1037
1038	  If unsure, say Y.
1039
1040config CAVIUM_ERRATUM_23154
1041	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1042	default y
1043	help
1044	  The ThunderX GICv3 implementation requires a modified version for
1045	  reading the IAR status to ensure data synchronization
1046	  (access to icc_iar1_el1 is not sync'ed before and after).
1047
1048	  It also suffers from erratum 38545 (also present on Marvell's
1049	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1050	  spuriously presented to the CPU interface.
1051
1052	  If unsure, say Y.
1053
1054config CAVIUM_ERRATUM_27456
1055	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1056	default y
1057	help
1058	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1059	  instructions may cause the icache to become corrupted if it
1060	  contains data for a non-current ASID.  The fix is to
1061	  invalidate the icache when changing the mm context.
1062
1063	  If unsure, say Y.
1064
1065config CAVIUM_ERRATUM_30115
1066	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1067	default y
1068	help
1069	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1070	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1071	  interrupts in host. Trapping both GICv3 group-0 and group-1
1072	  accesses sidesteps the issue.
1073
1074	  If unsure, say Y.
1075
1076config CAVIUM_TX2_ERRATUM_219
1077	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1078	default y
1079	help
1080	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1081	  TTBR update and the corresponding context synchronizing operation can
1082	  cause a spurious Data Abort to be delivered to any hardware thread in
1083	  the CPU core.
1084
1085	  Work around the issue by avoiding the problematic code sequence and
1086	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1087	  trap handler performs the corresponding register access, skips the
1088	  instruction and ensures context synchronization by virtue of the
1089	  exception return.
1090
1091	  If unsure, say Y.
1092
1093config FUJITSU_ERRATUM_010001
1094	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1095	default y
1096	help
1097	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1098	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1099	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1100	  This fault occurs under a specific hardware condition when a
1101	  load/store instruction performs an address translation using:
1102	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1103	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1104	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1105	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1106
1107	  The workaround is to ensure these bits are clear in TCR_ELx.
1108	  The workaround only affects the Fujitsu-A64FX.
1109
1110	  If unsure, say Y.
1111
1112config HISILICON_ERRATUM_161600802
1113	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1114	default y
1115	help
1116	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1117	  when issued ITS commands such as VMOVP and VMAPP, and requires
1118	  a 128kB offset to be applied to the target address in this commands.
1119
1120	  If unsure, say Y.
1121
1122config QCOM_FALKOR_ERRATUM_1003
1123	bool "Falkor E1003: Incorrect translation due to ASID change"
1124	default y
1125	help
1126	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1127	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1128	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1129	  then only for entries in the walk cache, since the leaf translation
1130	  is unchanged. Work around the erratum by invalidating the walk cache
1131	  entries for the trampoline before entering the kernel proper.
1132
1133config QCOM_FALKOR_ERRATUM_1009
1134	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1135	default y
1136	select ARM64_WORKAROUND_REPEAT_TLBI
1137	help
1138	  On Falkor v1, the CPU may prematurely complete a DSB following a
1139	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1140	  one more time to fix the issue.
1141
1142	  If unsure, say Y.
1143
1144config QCOM_QDF2400_ERRATUM_0065
1145	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1146	default y
1147	help
1148	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1149	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1150	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1151
1152	  If unsure, say Y.
1153
1154config QCOM_FALKOR_ERRATUM_E1041
1155	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1156	default y
1157	help
1158	  Falkor CPU may speculatively fetch instructions from an improper
1159	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1160	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1161
1162	  If unsure, say Y.
1163
1164config NVIDIA_CARMEL_CNP_ERRATUM
1165	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1166	default y
1167	help
1168	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1169	  invalidate shared TLB entries installed by a different core, as it would
1170	  on standard ARM cores.
1171
1172	  If unsure, say Y.
1173
1174config ROCKCHIP_ERRATUM_3588001
1175	bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1176	default y
1177	help
1178	  The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1179	  This means, that its sharability feature may not be used, even though it
1180	  is supported by the IP itself.
1181
1182	  If unsure, say Y.
1183
1184config SOCIONEXT_SYNQUACER_PREITS
1185	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1186	default y
1187	help
1188	  Socionext Synquacer SoCs implement a separate h/w block to generate
1189	  MSI doorbell writes with non-zero values for the device ID.
1190
1191	  If unsure, say Y.
1192
1193endmenu # "ARM errata workarounds via the alternatives framework"
1194
1195choice
1196	prompt "Page size"
1197	default ARM64_4K_PAGES
1198	help
1199	  Page size (translation granule) configuration.
1200
1201config ARM64_4K_PAGES
1202	bool "4KB"
1203	help
1204	  This feature enables 4KB pages support.
1205
1206config ARM64_16K_PAGES
1207	bool "16KB"
1208	help
1209	  The system will use 16KB pages support. AArch32 emulation
1210	  requires applications compiled with 16K (or a multiple of 16K)
1211	  aligned segments.
1212
1213config ARM64_64K_PAGES
1214	bool "64KB"
1215	help
1216	  This feature enables 64KB pages support (4KB by default)
1217	  allowing only two levels of page tables and faster TLB
1218	  look-up. AArch32 emulation requires applications compiled
1219	  with 64K aligned segments.
1220
1221endchoice
1222
1223choice
1224	prompt "Virtual address space size"
1225	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
1226	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
1227	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
1228	help
1229	  Allows choosing one of multiple possible virtual address
1230	  space sizes. The level of translation table is determined by
1231	  a combination of page size and virtual address space size.
1232
1233config ARM64_VA_BITS_36
1234	bool "36-bit" if EXPERT
1235	depends on ARM64_16K_PAGES
1236
1237config ARM64_VA_BITS_39
1238	bool "39-bit"
1239	depends on ARM64_4K_PAGES
1240
1241config ARM64_VA_BITS_42
1242	bool "42-bit"
1243	depends on ARM64_64K_PAGES
1244
1245config ARM64_VA_BITS_47
1246	bool "47-bit"
1247	depends on ARM64_16K_PAGES
1248
1249config ARM64_VA_BITS_48
1250	bool "48-bit"
1251
1252config ARM64_VA_BITS_52
1253	bool "52-bit"
1254	depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
1255	help
1256	  Enable 52-bit virtual addressing for userspace when explicitly
1257	  requested via a hint to mmap(). The kernel will also use 52-bit
1258	  virtual addresses for its own mappings (provided HW support for
1259	  this feature is available, otherwise it reverts to 48-bit).
1260
1261	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1262	  ARMv8.3 Pointer Authentication will result in the PAC being
1263	  reduced from 7 bits to 3 bits, which may have a significant
1264	  impact on its susceptibility to brute-force attacks.
1265
1266	  If unsure, select 48-bit virtual addressing instead.
1267
1268endchoice
1269
1270config ARM64_FORCE_52BIT
1271	bool "Force 52-bit virtual addresses for userspace"
1272	depends on ARM64_VA_BITS_52 && EXPERT
1273	help
1274	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1275	  to maintain compatibility with older software by providing 48-bit VAs
1276	  unless a hint is supplied to mmap.
1277
1278	  This configuration option disables the 48-bit compatibility logic, and
1279	  forces all userspace addresses to be 52-bit on HW that supports it. One
1280	  should only enable this configuration option for stress testing userspace
1281	  memory management code. If unsure say N here.
1282
1283config ARM64_VA_BITS
1284	int
1285	default 36 if ARM64_VA_BITS_36
1286	default 39 if ARM64_VA_BITS_39
1287	default 42 if ARM64_VA_BITS_42
1288	default 47 if ARM64_VA_BITS_47
1289	default 48 if ARM64_VA_BITS_48
1290	default 52 if ARM64_VA_BITS_52
1291
1292choice
1293	prompt "Physical address space size"
1294	default ARM64_PA_BITS_48
1295	help
1296	  Choose the maximum physical address range that the kernel will
1297	  support.
1298
1299config ARM64_PA_BITS_48
1300	bool "48-bit"
1301
1302config ARM64_PA_BITS_52
1303	bool "52-bit (ARMv8.2)"
1304	depends on ARM64_64K_PAGES
1305	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1306	help
1307	  Enable support for a 52-bit physical address space, introduced as
1308	  part of the ARMv8.2-LPA extension.
1309
1310	  With this enabled, the kernel will also continue to work on CPUs that
1311	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1312	  minor performance overhead).
1313
1314endchoice
1315
1316config ARM64_PA_BITS
1317	int
1318	default 48 if ARM64_PA_BITS_48
1319	default 52 if ARM64_PA_BITS_52
1320
1321choice
1322	prompt "Endianness"
1323	default CPU_LITTLE_ENDIAN
1324	help
1325	  Select the endianness of data accesses performed by the CPU. Userspace
1326	  applications will need to be compiled and linked for the endianness
1327	  that is selected here.
1328
1329config CPU_BIG_ENDIAN
1330	bool "Build big-endian kernel"
1331	depends on !LD_IS_LLD || LLD_VERSION >= 130000
1332	help
1333	  Say Y if you plan on running a kernel with a big-endian userspace.
1334
1335config CPU_LITTLE_ENDIAN
1336	bool "Build little-endian kernel"
1337	help
1338	  Say Y if you plan on running a kernel with a little-endian userspace.
1339	  This is usually the case for distributions targeting arm64.
1340
1341endchoice
1342
1343config SCHED_MC
1344	bool "Multi-core scheduler support"
1345	help
1346	  Multi-core scheduler support improves the CPU scheduler's decision
1347	  making when dealing with multi-core CPU chips at a cost of slightly
1348	  increased overhead in some places. If unsure say N here.
1349
1350config SCHED_CLUSTER
1351	bool "Cluster scheduler support"
1352	help
1353	  Cluster scheduler support improves the CPU scheduler's decision
1354	  making when dealing with machines that have clusters of CPUs.
1355	  Cluster usually means a couple of CPUs which are placed closely
1356	  by sharing mid-level caches, last-level cache tags or internal
1357	  busses.
1358
1359config SCHED_SMT
1360	bool "SMT scheduler support"
1361	help
1362	  Improves the CPU scheduler's decision making when dealing with
1363	  MultiThreading at a cost of slightly increased overhead in some
1364	  places. If unsure say N here.
1365
1366config NR_CPUS
1367	int "Maximum number of CPUs (2-4096)"
1368	range 2 4096
1369	default "256"
1370
1371config HOTPLUG_CPU
1372	bool "Support for hot-pluggable CPUs"
1373	select GENERIC_IRQ_MIGRATION
1374	help
1375	  Say Y here to experiment with turning CPUs off and on.  CPUs
1376	  can be controlled through /sys/devices/system/cpu.
1377
1378# Common NUMA Features
1379config NUMA
1380	bool "NUMA Memory Allocation and Scheduler Support"
1381	select GENERIC_ARCH_NUMA
1382	select ACPI_NUMA if ACPI
1383	select OF_NUMA
1384	select HAVE_SETUP_PER_CPU_AREA
1385	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1386	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1387	select USE_PERCPU_NUMA_NODE_ID
1388	help
1389	  Enable NUMA (Non-Uniform Memory Access) support.
1390
1391	  The kernel will try to allocate memory used by a CPU on the
1392	  local memory of the CPU and add some more
1393	  NUMA awareness to the kernel.
1394
1395config NODES_SHIFT
1396	int "Maximum NUMA Nodes (as a power of 2)"
1397	range 1 10
1398	default "4"
1399	depends on NUMA
1400	help
1401	  Specify the maximum number of NUMA Nodes available on the target
1402	  system.  Increases memory reserved to accommodate various tables.
1403
1404source "kernel/Kconfig.hz"
1405
1406config ARCH_SPARSEMEM_ENABLE
1407	def_bool y
1408	select SPARSEMEM_VMEMMAP_ENABLE
1409	select SPARSEMEM_VMEMMAP
1410
1411config HW_PERF_EVENTS
1412	def_bool y
1413	depends on ARM_PMU
1414
1415# Supported by clang >= 7.0 or GCC >= 12.0.0
1416config CC_HAVE_SHADOW_CALL_STACK
1417	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1418
1419config PARAVIRT
1420	bool "Enable paravirtualization code"
1421	help
1422	  This changes the kernel so it can modify itself when it is run
1423	  under a hypervisor, potentially improving performance significantly
1424	  over full virtualization.
1425
1426config PARAVIRT_TIME_ACCOUNTING
1427	bool "Paravirtual steal time accounting"
1428	select PARAVIRT
1429	help
1430	  Select this option to enable fine granularity task steal time
1431	  accounting. Time spent executing other tasks in parallel with
1432	  the current vCPU is discounted from the vCPU power. To account for
1433	  that, there can be a small performance impact.
1434
1435	  If in doubt, say N here.
1436
1437config KEXEC
1438	depends on PM_SLEEP_SMP
1439	select KEXEC_CORE
1440	bool "kexec system call"
1441	help
1442	  kexec is a system call that implements the ability to shutdown your
1443	  current kernel, and to start another kernel.  It is like a reboot
1444	  but it is independent of the system firmware.   And like a reboot
1445	  you can start any kernel with it, not just Linux.
1446
1447config KEXEC_FILE
1448	bool "kexec file based system call"
1449	select KEXEC_CORE
1450	select HAVE_IMA_KEXEC if IMA
1451	help
1452	  This is new version of kexec system call. This system call is
1453	  file based and takes file descriptors as system call argument
1454	  for kernel and initramfs as opposed to list of segments as
1455	  accepted by previous system call.
1456
1457config KEXEC_SIG
1458	bool "Verify kernel signature during kexec_file_load() syscall"
1459	depends on KEXEC_FILE
1460	help
1461	  Select this option to verify a signature with loaded kernel
1462	  image. If configured, any attempt of loading a image without
1463	  valid signature will fail.
1464
1465	  In addition to that option, you need to enable signature
1466	  verification for the corresponding kernel image type being
1467	  loaded in order for this to work.
1468
1469config KEXEC_IMAGE_VERIFY_SIG
1470	bool "Enable Image signature verification support"
1471	default y
1472	depends on KEXEC_SIG
1473	depends on EFI && SIGNED_PE_FILE_VERIFICATION
1474	help
1475	  Enable Image signature verification support.
1476
1477comment "Support for PE file signature verification disabled"
1478	depends on KEXEC_SIG
1479	depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
1480
1481config CRASH_DUMP
1482	bool "Build kdump crash kernel"
1483	help
1484	  Generate crash dump after being started by kexec. This should
1485	  be normally only set in special crash dump kernels which are
1486	  loaded in the main kernel with kexec-tools into a specially
1487	  reserved region and then later executed after a crash by
1488	  kdump/kexec.
1489
1490	  For more details see Documentation/admin-guide/kdump/kdump.rst
1491
1492config TRANS_TABLE
1493	def_bool y
1494	depends on HIBERNATION || KEXEC_CORE
1495
1496config XEN_DOM0
1497	def_bool y
1498	depends on XEN
1499
1500config XEN
1501	bool "Xen guest support on ARM64"
1502	depends on ARM64 && OF
1503	select SWIOTLB_XEN
1504	select PARAVIRT
1505	help
1506	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1507
1508# include/linux/mmzone.h requires the following to be true:
1509#
1510#   MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1511#
1512# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1513#
1514#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_ORDER  |  default MAX_ORDER |
1515# ----+-------------------+--------------+-----------------+--------------------+
1516# 4K  |       27          |      12      |       15        |         10         |
1517# 16K |       27          |      14      |       13        |         11         |
1518# 64K |       29          |      16      |       13        |         13         |
1519config ARCH_FORCE_MAX_ORDER
1520	int
1521	default "13" if ARM64_64K_PAGES
1522	default "11" if ARM64_16K_PAGES
1523	default "10"
1524	help
1525	  The kernel page allocator limits the size of maximal physically
1526	  contiguous allocations. The limit is called MAX_ORDER and it
1527	  defines the maximal power of two of number of pages that can be
1528	  allocated as a single contiguous block. This option allows
1529	  overriding the default setting when ability to allocate very
1530	  large blocks of physically contiguous memory is required.
1531
1532	  The maximal size of allocation cannot exceed the size of the
1533	  section, so the value of MAX_ORDER should satisfy
1534
1535	    MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1536
1537	  Don't change if unsure.
1538
1539config UNMAP_KERNEL_AT_EL0
1540	bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
1541	default y
1542	help
1543	  Speculation attacks against some high-performance processors can
1544	  be used to bypass MMU permission checks and leak kernel data to
1545	  userspace. This can be defended against by unmapping the kernel
1546	  when running in userspace, mapping it back in on exception entry
1547	  via a trampoline page in the vector table.
1548
1549	  If unsure, say Y.
1550
1551config MITIGATE_SPECTRE_BRANCH_HISTORY
1552	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1553	default y
1554	help
1555	  Speculation attacks against some high-performance processors can
1556	  make use of branch history to influence future speculation.
1557	  When taking an exception from user-space, a sequence of branches
1558	  or a firmware call overwrites the branch history.
1559
1560config RODATA_FULL_DEFAULT_ENABLED
1561	bool "Apply r/o permissions of VM areas also to their linear aliases"
1562	default y
1563	help
1564	  Apply read-only attributes of VM areas to the linear alias of
1565	  the backing pages as well. This prevents code or read-only data
1566	  from being modified (inadvertently or intentionally) via another
1567	  mapping of the same memory page. This additional enhancement can
1568	  be turned off at runtime by passing rodata=[off|on] (and turned on
1569	  with rodata=full if this option is set to 'n')
1570
1571	  This requires the linear region to be mapped down to pages,
1572	  which may adversely affect performance in some cases.
1573
1574config ARM64_SW_TTBR0_PAN
1575	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1576	help
1577	  Enabling this option prevents the kernel from accessing
1578	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1579	  zeroed area and reserved ASID. The user access routines
1580	  restore the valid TTBR0_EL1 temporarily.
1581
1582config ARM64_TAGGED_ADDR_ABI
1583	bool "Enable the tagged user addresses syscall ABI"
1584	default y
1585	help
1586	  When this option is enabled, user applications can opt in to a
1587	  relaxed ABI via prctl() allowing tagged addresses to be passed
1588	  to system calls as pointer arguments. For details, see
1589	  Documentation/arch/arm64/tagged-address-abi.rst.
1590
1591menuconfig COMPAT
1592	bool "Kernel support for 32-bit EL0"
1593	depends on ARM64_4K_PAGES || EXPERT
1594	select HAVE_UID16
1595	select OLD_SIGSUSPEND3
1596	select COMPAT_OLD_SIGACTION
1597	help
1598	  This option enables support for a 32-bit EL0 running under a 64-bit
1599	  kernel at EL1. AArch32-specific components such as system calls,
1600	  the user helper functions, VFP support and the ptrace interface are
1601	  handled appropriately by the kernel.
1602
1603	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1604	  that you will only be able to execute AArch32 binaries that were compiled
1605	  with page size aligned segments.
1606
1607	  If you want to execute 32-bit userspace applications, say Y.
1608
1609if COMPAT
1610
1611config KUSER_HELPERS
1612	bool "Enable kuser helpers page for 32-bit applications"
1613	default y
1614	help
1615	  Warning: disabling this option may break 32-bit user programs.
1616
1617	  Provide kuser helpers to compat tasks. The kernel provides
1618	  helper code to userspace in read only form at a fixed location
1619	  to allow userspace to be independent of the CPU type fitted to
1620	  the system. This permits binaries to be run on ARMv4 through
1621	  to ARMv8 without modification.
1622
1623	  See Documentation/arch/arm/kernel_user_helpers.rst for details.
1624
1625	  However, the fixed address nature of these helpers can be used
1626	  by ROP (return orientated programming) authors when creating
1627	  exploits.
1628
1629	  If all of the binaries and libraries which run on your platform
1630	  are built specifically for your platform, and make no use of
1631	  these helpers, then you can turn this option off to hinder
1632	  such exploits. However, in that case, if a binary or library
1633	  relying on those helpers is run, it will not function correctly.
1634
1635	  Say N here only if you are absolutely certain that you do not
1636	  need these helpers; otherwise, the safe option is to say Y.
1637
1638config COMPAT_VDSO
1639	bool "Enable vDSO for 32-bit applications"
1640	depends on !CPU_BIG_ENDIAN
1641	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1642	select GENERIC_COMPAT_VDSO
1643	default y
1644	help
1645	  Place in the process address space of 32-bit applications an
1646	  ELF shared object providing fast implementations of gettimeofday
1647	  and clock_gettime.
1648
1649	  You must have a 32-bit build of glibc 2.22 or later for programs
1650	  to seamlessly take advantage of this.
1651
1652config THUMB2_COMPAT_VDSO
1653	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1654	depends on COMPAT_VDSO
1655	default y
1656	help
1657	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1658	  otherwise with '-marm'.
1659
1660config COMPAT_ALIGNMENT_FIXUPS
1661	bool "Fix up misaligned multi-word loads and stores in user space"
1662
1663menuconfig ARMV8_DEPRECATED
1664	bool "Emulate deprecated/obsolete ARMv8 instructions"
1665	depends on SYSCTL
1666	help
1667	  Legacy software support may require certain instructions
1668	  that have been deprecated or obsoleted in the architecture.
1669
1670	  Enable this config to enable selective emulation of these
1671	  features.
1672
1673	  If unsure, say Y
1674
1675if ARMV8_DEPRECATED
1676
1677config SWP_EMULATION
1678	bool "Emulate SWP/SWPB instructions"
1679	help
1680	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1681	  they are always undefined. Say Y here to enable software
1682	  emulation of these instructions for userspace using LDXR/STXR.
1683	  This feature can be controlled at runtime with the abi.swp
1684	  sysctl which is disabled by default.
1685
1686	  In some older versions of glibc [<=2.8] SWP is used during futex
1687	  trylock() operations with the assumption that the code will not
1688	  be preempted. This invalid assumption may be more likely to fail
1689	  with SWP emulation enabled, leading to deadlock of the user
1690	  application.
1691
1692	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1693	  on an external transaction monitoring block called a global
1694	  monitor to maintain update atomicity. If your system does not
1695	  implement a global monitor, this option can cause programs that
1696	  perform SWP operations to uncached memory to deadlock.
1697
1698	  If unsure, say Y
1699
1700config CP15_BARRIER_EMULATION
1701	bool "Emulate CP15 Barrier instructions"
1702	help
1703	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1704	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1705	  strongly recommended to use the ISB, DSB, and DMB
1706	  instructions instead.
1707
1708	  Say Y here to enable software emulation of these
1709	  instructions for AArch32 userspace code. When this option is
1710	  enabled, CP15 barrier usage is traced which can help
1711	  identify software that needs updating. This feature can be
1712	  controlled at runtime with the abi.cp15_barrier sysctl.
1713
1714	  If unsure, say Y
1715
1716config SETEND_EMULATION
1717	bool "Emulate SETEND instruction"
1718	help
1719	  The SETEND instruction alters the data-endianness of the
1720	  AArch32 EL0, and is deprecated in ARMv8.
1721
1722	  Say Y here to enable software emulation of the instruction
1723	  for AArch32 userspace code. This feature can be controlled
1724	  at runtime with the abi.setend sysctl.
1725
1726	  Note: All the cpus on the system must have mixed endian support at EL0
1727	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1728	  endian - is hotplugged in after this feature has been enabled, there could
1729	  be unexpected results in the applications.
1730
1731	  If unsure, say Y
1732endif # ARMV8_DEPRECATED
1733
1734endif # COMPAT
1735
1736menu "ARMv8.1 architectural features"
1737
1738config ARM64_HW_AFDBM
1739	bool "Support for hardware updates of the Access and Dirty page flags"
1740	default y
1741	help
1742	  The ARMv8.1 architecture extensions introduce support for
1743	  hardware updates of the access and dirty information in page
1744	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1745	  capable processors, accesses to pages with PTE_AF cleared will
1746	  set this bit instead of raising an access flag fault.
1747	  Similarly, writes to read-only pages with the DBM bit set will
1748	  clear the read-only bit (AP[2]) instead of raising a
1749	  permission fault.
1750
1751	  Kernels built with this configuration option enabled continue
1752	  to work on pre-ARMv8.1 hardware and the performance impact is
1753	  minimal. If unsure, say Y.
1754
1755config ARM64_PAN
1756	bool "Enable support for Privileged Access Never (PAN)"
1757	default y
1758	help
1759	  Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1760	  prevents the kernel or hypervisor from accessing user-space (EL0)
1761	  memory directly.
1762
1763	  Choosing this option will cause any unprotected (not using
1764	  copy_to_user et al) memory access to fail with a permission fault.
1765
1766	  The feature is detected at runtime, and will remain as a 'nop'
1767	  instruction if the cpu does not implement the feature.
1768
1769config AS_HAS_LDAPR
1770	def_bool $(as-instr,.arch_extension rcpc)
1771
1772config AS_HAS_LSE_ATOMICS
1773	def_bool $(as-instr,.arch_extension lse)
1774
1775config ARM64_LSE_ATOMICS
1776	bool
1777	default ARM64_USE_LSE_ATOMICS
1778	depends on AS_HAS_LSE_ATOMICS
1779
1780config ARM64_USE_LSE_ATOMICS
1781	bool "Atomic instructions"
1782	default y
1783	help
1784	  As part of the Large System Extensions, ARMv8.1 introduces new
1785	  atomic instructions that are designed specifically to scale in
1786	  very large systems.
1787
1788	  Say Y here to make use of these instructions for the in-kernel
1789	  atomic routines. This incurs a small overhead on CPUs that do
1790	  not support these instructions and requires the kernel to be
1791	  built with binutils >= 2.25 in order for the new instructions
1792	  to be used.
1793
1794endmenu # "ARMv8.1 architectural features"
1795
1796menu "ARMv8.2 architectural features"
1797
1798config AS_HAS_ARMV8_2
1799	def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a)
1800
1801config AS_HAS_SHA3
1802	def_bool $(as-instr,.arch armv8.2-a+sha3)
1803
1804config ARM64_PMEM
1805	bool "Enable support for persistent memory"
1806	select ARCH_HAS_PMEM_API
1807	select ARCH_HAS_UACCESS_FLUSHCACHE
1808	help
1809	  Say Y to enable support for the persistent memory API based on the
1810	  ARMv8.2 DCPoP feature.
1811
1812	  The feature is detected at runtime, and the kernel will use DC CVAC
1813	  operations if DC CVAP is not supported (following the behaviour of
1814	  DC CVAP itself if the system does not define a point of persistence).
1815
1816config ARM64_RAS_EXTN
1817	bool "Enable support for RAS CPU Extensions"
1818	default y
1819	help
1820	  CPUs that support the Reliability, Availability and Serviceability
1821	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1822	  errors, classify them and report them to software.
1823
1824	  On CPUs with these extensions system software can use additional
1825	  barriers to determine if faults are pending and read the
1826	  classification from a new set of registers.
1827
1828	  Selecting this feature will allow the kernel to use these barriers
1829	  and access the new registers if the system supports the extension.
1830	  Platform RAS features may additionally depend on firmware support.
1831
1832config ARM64_CNP
1833	bool "Enable support for Common Not Private (CNP) translations"
1834	default y
1835	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1836	help
1837	  Common Not Private (CNP) allows translation table entries to
1838	  be shared between different PEs in the same inner shareable
1839	  domain, so the hardware can use this fact to optimise the
1840	  caching of such entries in the TLB.
1841
1842	  Selecting this option allows the CNP feature to be detected
1843	  at runtime, and does not affect PEs that do not implement
1844	  this feature.
1845
1846endmenu # "ARMv8.2 architectural features"
1847
1848menu "ARMv8.3 architectural features"
1849
1850config ARM64_PTR_AUTH
1851	bool "Enable support for pointer authentication"
1852	default y
1853	help
1854	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1855	  instructions for signing and authenticating pointers against secret
1856	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1857	  and other attacks.
1858
1859	  This option enables these instructions at EL0 (i.e. for userspace).
1860	  Choosing this option will cause the kernel to initialise secret keys
1861	  for each process at exec() time, with these keys being
1862	  context-switched along with the process.
1863
1864	  The feature is detected at runtime. If the feature is not present in
1865	  hardware it will not be advertised to userspace/KVM guest nor will it
1866	  be enabled.
1867
1868	  If the feature is present on the boot CPU but not on a late CPU, then
1869	  the late CPU will be parked. Also, if the boot CPU does not have
1870	  address auth and the late CPU has then the late CPU will still boot
1871	  but with the feature disabled. On such a system, this option should
1872	  not be selected.
1873
1874config ARM64_PTR_AUTH_KERNEL
1875	bool "Use pointer authentication for kernel"
1876	default y
1877	depends on ARM64_PTR_AUTH
1878	depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_ARMV8_3
1879	# Modern compilers insert a .note.gnu.property section note for PAC
1880	# which is only understood by binutils starting with version 2.33.1.
1881	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1882	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1883	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1884	help
1885	  If the compiler supports the -mbranch-protection or
1886	  -msign-return-address flag (e.g. GCC 7 or later), then this option
1887	  will cause the kernel itself to be compiled with return address
1888	  protection. In this case, and if the target hardware is known to
1889	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
1890	  disabled with minimal loss of protection.
1891
1892	  This feature works with FUNCTION_GRAPH_TRACER option only if
1893	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
1894
1895config CC_HAS_BRANCH_PROT_PAC_RET
1896	# GCC 9 or later, clang 8 or later
1897	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1898
1899config CC_HAS_SIGN_RETURN_ADDRESS
1900	# GCC 7, 8
1901	def_bool $(cc-option,-msign-return-address=all)
1902
1903config AS_HAS_ARMV8_3
1904	def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
1905
1906config AS_HAS_CFI_NEGATE_RA_STATE
1907	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1908
1909endmenu # "ARMv8.3 architectural features"
1910
1911menu "ARMv8.4 architectural features"
1912
1913config ARM64_AMU_EXTN
1914	bool "Enable support for the Activity Monitors Unit CPU extension"
1915	default y
1916	help
1917	  The activity monitors extension is an optional extension introduced
1918	  by the ARMv8.4 CPU architecture. This enables support for version 1
1919	  of the activity monitors architecture, AMUv1.
1920
1921	  To enable the use of this extension on CPUs that implement it, say Y.
1922
1923	  Note that for architectural reasons, firmware _must_ implement AMU
1924	  support when running on CPUs that present the activity monitors
1925	  extension. The required support is present in:
1926	    * Version 1.5 and later of the ARM Trusted Firmware
1927
1928	  For kernels that have this configuration enabled but boot with broken
1929	  firmware, you may need to say N here until the firmware is fixed.
1930	  Otherwise you may experience firmware panics or lockups when
1931	  accessing the counter registers. Even if you are not observing these
1932	  symptoms, the values returned by the register reads might not
1933	  correctly reflect reality. Most commonly, the value read will be 0,
1934	  indicating that the counter is not enabled.
1935
1936config AS_HAS_ARMV8_4
1937	def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
1938
1939config ARM64_TLB_RANGE
1940	bool "Enable support for tlbi range feature"
1941	default y
1942	depends on AS_HAS_ARMV8_4
1943	help
1944	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
1945	  range of input addresses.
1946
1947	  The feature introduces new assembly instructions, and they were
1948	  support when binutils >= 2.30.
1949
1950endmenu # "ARMv8.4 architectural features"
1951
1952menu "ARMv8.5 architectural features"
1953
1954config AS_HAS_ARMV8_5
1955	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
1956
1957config ARM64_BTI
1958	bool "Branch Target Identification support"
1959	default y
1960	help
1961	  Branch Target Identification (part of the ARMv8.5 Extensions)
1962	  provides a mechanism to limit the set of locations to which computed
1963	  branch instructions such as BR or BLR can jump.
1964
1965	  To make use of BTI on CPUs that support it, say Y.
1966
1967	  BTI is intended to provide complementary protection to other control
1968	  flow integrity protection mechanisms, such as the Pointer
1969	  authentication mechanism provided as part of the ARMv8.3 Extensions.
1970	  For this reason, it does not make sense to enable this option without
1971	  also enabling support for pointer authentication.  Thus, when
1972	  enabling this option you should also select ARM64_PTR_AUTH=y.
1973
1974	  Userspace binaries must also be specifically compiled to make use of
1975	  this mechanism.  If you say N here or the hardware does not support
1976	  BTI, such binaries can still run, but you get no additional
1977	  enforcement of branch destinations.
1978
1979config ARM64_BTI_KERNEL
1980	bool "Use Branch Target Identification for kernel"
1981	default y
1982	depends on ARM64_BTI
1983	depends on ARM64_PTR_AUTH_KERNEL
1984	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
1985	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
1986	depends on !CC_IS_GCC || GCC_VERSION >= 100100
1987	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
1988	depends on !CC_IS_GCC
1989	# https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9
1990	depends on !CC_IS_CLANG || CLANG_VERSION >= 120000
1991	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1992	help
1993	  Build the kernel with Branch Target Identification annotations
1994	  and enable enforcement of this for kernel code. When this option
1995	  is enabled and the system supports BTI all kernel code including
1996	  modular code must have BTI enabled.
1997
1998config CC_HAS_BRANCH_PROT_PAC_RET_BTI
1999	# GCC 9 or later, clang 8 or later
2000	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2001
2002config ARM64_E0PD
2003	bool "Enable support for E0PD"
2004	default y
2005	help
2006	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
2007	  that EL0 accesses made via TTBR1 always fault in constant time,
2008	  providing similar benefits to KASLR as those provided by KPTI, but
2009	  with lower overhead and without disrupting legitimate access to
2010	  kernel memory such as SPE.
2011
2012	  This option enables E0PD for TTBR1 where available.
2013
2014config ARM64_AS_HAS_MTE
2015	# Initial support for MTE went in binutils 2.32.0, checked with
2016	# ".arch armv8.5-a+memtag" below. However, this was incomplete
2017	# as a late addition to the final architecture spec (LDGM/STGM)
2018	# is only supported in the newer 2.32.x and 2.33 binutils
2019	# versions, hence the extra "stgm" instruction check below.
2020	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2021
2022config ARM64_MTE
2023	bool "Memory Tagging Extension support"
2024	default y
2025	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2026	depends on AS_HAS_ARMV8_5
2027	depends on AS_HAS_LSE_ATOMICS
2028	# Required for tag checking in the uaccess routines
2029	depends on ARM64_PAN
2030	select ARCH_HAS_SUBPAGE_FAULTS
2031	select ARCH_USES_HIGH_VMA_FLAGS
2032	select ARCH_USES_PG_ARCH_X
2033	help
2034	  Memory Tagging (part of the ARMv8.5 Extensions) provides
2035	  architectural support for run-time, always-on detection of
2036	  various classes of memory error to aid with software debugging
2037	  to eliminate vulnerabilities arising from memory-unsafe
2038	  languages.
2039
2040	  This option enables the support for the Memory Tagging
2041	  Extension at EL0 (i.e. for userspace).
2042
2043	  Selecting this option allows the feature to be detected at
2044	  runtime. Any secondary CPU not implementing this feature will
2045	  not be allowed a late bring-up.
2046
2047	  Userspace binaries that want to use this feature must
2048	  explicitly opt in. The mechanism for the userspace is
2049	  described in:
2050
2051	  Documentation/arch/arm64/memory-tagging-extension.rst.
2052
2053endmenu # "ARMv8.5 architectural features"
2054
2055menu "ARMv8.7 architectural features"
2056
2057config ARM64_EPAN
2058	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2059	default y
2060	depends on ARM64_PAN
2061	help
2062	  Enhanced Privileged Access Never (EPAN) allows Privileged
2063	  Access Never to be used with Execute-only mappings.
2064
2065	  The feature is detected at runtime, and will remain disabled
2066	  if the cpu does not implement the feature.
2067endmenu # "ARMv8.7 architectural features"
2068
2069config ARM64_SVE
2070	bool "ARM Scalable Vector Extension support"
2071	default y
2072	help
2073	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2074	  execution state which complements and extends the SIMD functionality
2075	  of the base architecture to support much larger vectors and to enable
2076	  additional vectorisation opportunities.
2077
2078	  To enable use of this extension on CPUs that implement it, say Y.
2079
2080	  On CPUs that support the SVE2 extensions, this option will enable
2081	  those too.
2082
2083	  Note that for architectural reasons, firmware _must_ implement SVE
2084	  support when running on SVE capable hardware.  The required support
2085	  is present in:
2086
2087	    * version 1.5 and later of the ARM Trusted Firmware
2088	    * the AArch64 boot wrapper since commit 5e1261e08abf
2089	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2090
2091	  For other firmware implementations, consult the firmware documentation
2092	  or vendor.
2093
2094	  If you need the kernel to boot on SVE-capable hardware with broken
2095	  firmware, you may need to say N here until you get your firmware
2096	  fixed.  Otherwise, you may experience firmware panics or lockups when
2097	  booting the kernel.  If unsure and you are not observing these
2098	  symptoms, you should assume that it is safe to say Y.
2099
2100config ARM64_SME
2101	bool "ARM Scalable Matrix Extension support"
2102	default y
2103	depends on ARM64_SVE
2104	help
2105	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2106	  execution state which utilises a substantial subset of the SVE
2107	  instruction set, together with the addition of new architectural
2108	  register state capable of holding two dimensional matrix tiles to
2109	  enable various matrix operations.
2110
2111config ARM64_PSEUDO_NMI
2112	bool "Support for NMI-like interrupts"
2113	select ARM_GIC_V3
2114	help
2115	  Adds support for mimicking Non-Maskable Interrupts through the use of
2116	  GIC interrupt priority. This support requires version 3 or later of
2117	  ARM GIC.
2118
2119	  This high priority configuration for interrupts needs to be
2120	  explicitly enabled by setting the kernel parameter
2121	  "irqchip.gicv3_pseudo_nmi" to 1.
2122
2123	  If unsure, say N
2124
2125if ARM64_PSEUDO_NMI
2126config ARM64_DEBUG_PRIORITY_MASKING
2127	bool "Debug interrupt priority masking"
2128	help
2129	  This adds runtime checks to functions enabling/disabling
2130	  interrupts when using priority masking. The additional checks verify
2131	  the validity of ICC_PMR_EL1 when calling concerned functions.
2132
2133	  If unsure, say N
2134endif # ARM64_PSEUDO_NMI
2135
2136config RELOCATABLE
2137	bool "Build a relocatable kernel image" if EXPERT
2138	select ARCH_HAS_RELR
2139	default y
2140	help
2141	  This builds the kernel as a Position Independent Executable (PIE),
2142	  which retains all relocation metadata required to relocate the
2143	  kernel binary at runtime to a different virtual address than the
2144	  address it was linked at.
2145	  Since AArch64 uses the RELA relocation format, this requires a
2146	  relocation pass at runtime even if the kernel is loaded at the
2147	  same address it was linked at.
2148
2149config RANDOMIZE_BASE
2150	bool "Randomize the address of the kernel image"
2151	select RELOCATABLE
2152	help
2153	  Randomizes the virtual address at which the kernel image is
2154	  loaded, as a security feature that deters exploit attempts
2155	  relying on knowledge of the location of kernel internals.
2156
2157	  It is the bootloader's job to provide entropy, by passing a
2158	  random u64 value in /chosen/kaslr-seed at kernel entry.
2159
2160	  When booting via the UEFI stub, it will invoke the firmware's
2161	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2162	  to the kernel proper. In addition, it will randomise the physical
2163	  location of the kernel Image as well.
2164
2165	  If unsure, say N.
2166
2167config RANDOMIZE_MODULE_REGION_FULL
2168	bool "Randomize the module region over a 2 GB range"
2169	depends on RANDOMIZE_BASE
2170	default y
2171	help
2172	  Randomizes the location of the module region inside a 2 GB window
2173	  covering the core kernel. This way, it is less likely for modules
2174	  to leak information about the location of core kernel data structures
2175	  but it does imply that function calls between modules and the core
2176	  kernel will need to be resolved via veneers in the module PLT.
2177
2178	  When this option is not set, the module region will be randomized over
2179	  a limited range that contains the [_stext, _etext] interval of the
2180	  core kernel, so branch relocations are almost always in range unless
2181	  the region is exhausted. In this particular case of region
2182	  exhaustion, modules might be able to fall back to a larger 2GB area.
2183
2184config CC_HAVE_STACKPROTECTOR_SYSREG
2185	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2186
2187config STACKPROTECTOR_PER_TASK
2188	def_bool y
2189	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2190
2191config UNWIND_PATCH_PAC_INTO_SCS
2192	bool "Enable shadow call stack dynamically using code patching"
2193	# needs Clang with https://reviews.llvm.org/D111780 incorporated
2194	depends on CC_IS_CLANG && CLANG_VERSION >= 150000
2195	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2196	depends on SHADOW_CALL_STACK
2197	select UNWIND_TABLES
2198	select DYNAMIC_SCS
2199
2200endmenu # "Kernel Features"
2201
2202menu "Boot options"
2203
2204config ARM64_ACPI_PARKING_PROTOCOL
2205	bool "Enable support for the ARM64 ACPI parking protocol"
2206	depends on ACPI
2207	help
2208	  Enable support for the ARM64 ACPI parking protocol. If disabled
2209	  the kernel will not allow booting through the ARM64 ACPI parking
2210	  protocol even if the corresponding data is present in the ACPI
2211	  MADT table.
2212
2213config CMDLINE
2214	string "Default kernel command string"
2215	default ""
2216	help
2217	  Provide a set of default command-line options at build time by
2218	  entering them here. As a minimum, you should specify the the
2219	  root device (e.g. root=/dev/nfs).
2220
2221choice
2222	prompt "Kernel command line type" if CMDLINE != ""
2223	default CMDLINE_FROM_BOOTLOADER
2224	help
2225	  Choose how the kernel will handle the provided default kernel
2226	  command line string.
2227
2228config CMDLINE_FROM_BOOTLOADER
2229	bool "Use bootloader kernel arguments if available"
2230	help
2231	  Uses the command-line options passed by the boot loader. If
2232	  the boot loader doesn't provide any, the default kernel command
2233	  string provided in CMDLINE will be used.
2234
2235config CMDLINE_FORCE
2236	bool "Always use the default kernel command string"
2237	help
2238	  Always use the default kernel command string, even if the boot
2239	  loader passes other arguments to the kernel.
2240	  This is useful if you cannot or don't want to change the
2241	  command-line options your boot loader passes to the kernel.
2242
2243endchoice
2244
2245config EFI_STUB
2246	bool
2247
2248config EFI
2249	bool "UEFI runtime support"
2250	depends on OF && !CPU_BIG_ENDIAN
2251	depends on KERNEL_MODE_NEON
2252	select ARCH_SUPPORTS_ACPI
2253	select LIBFDT
2254	select UCS2_STRING
2255	select EFI_PARAMS_FROM_FDT
2256	select EFI_RUNTIME_WRAPPERS
2257	select EFI_STUB
2258	select EFI_GENERIC_STUB
2259	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2260	default y
2261	help
2262	  This option provides support for runtime services provided
2263	  by UEFI firmware (such as non-volatile variables, realtime
2264	  clock, and platform reset). A UEFI stub is also provided to
2265	  allow the kernel to be booted as an EFI application. This
2266	  is only useful on systems that have UEFI firmware.
2267
2268config DMI
2269	bool "Enable support for SMBIOS (DMI) tables"
2270	depends on EFI
2271	default y
2272	help
2273	  This enables SMBIOS/DMI feature for systems.
2274
2275	  This option is only useful on systems that have UEFI firmware.
2276	  However, even with this option, the resultant kernel should
2277	  continue to boot on existing non-UEFI platforms.
2278
2279endmenu # "Boot options"
2280
2281menu "Power management options"
2282
2283source "kernel/power/Kconfig"
2284
2285config ARCH_HIBERNATION_POSSIBLE
2286	def_bool y
2287	depends on CPU_PM
2288
2289config ARCH_HIBERNATION_HEADER
2290	def_bool y
2291	depends on HIBERNATION
2292
2293config ARCH_SUSPEND_POSSIBLE
2294	def_bool y
2295
2296endmenu # "Power management options"
2297
2298menu "CPU Power Management"
2299
2300source "drivers/cpuidle/Kconfig"
2301
2302source "drivers/cpufreq/Kconfig"
2303
2304endmenu # "CPU Power Management"
2305
2306source "drivers/acpi/Kconfig"
2307
2308source "arch/arm64/kvm/Kconfig"
2309
2310