xref: /openbmc/linux/arch/arm64/Kconfig (revision 5d7800d9)
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_BATCHED_UNMAP_TLB_FLUSH
100	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
101	select ARCH_WANT_DEFAULT_BPF_JIT
102	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
103	select ARCH_WANT_FRAME_POINTERS
104	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
105	select ARCH_WANT_LD_ORPHAN_WARN
106	select ARCH_WANTS_NO_INSTR
107	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
108	select ARCH_HAS_UBSAN_SANITIZE_ALL
109	select ARM_AMBA
110	select ARM_ARCH_TIMER
111	select ARM_GIC
112	select AUDIT_ARCH_COMPAT_GENERIC
113	select ARM_GIC_V2M if PCI
114	select ARM_GIC_V3
115	select ARM_GIC_V3_ITS if PCI
116	select ARM_PSCI_FW
117	select BUILDTIME_TABLE_SORT
118	select CLONE_BACKWARDS
119	select COMMON_CLK
120	select CPU_PM if (SUSPEND || CPU_IDLE)
121	select CRC32
122	select DCACHE_WORD_ACCESS
123	select DYNAMIC_FTRACE if FUNCTION_TRACER
124	select DMA_BOUNCE_UNALIGNED_KMALLOC
125	select DMA_DIRECT_REMAP
126	select EDAC_SUPPORT
127	select FRAME_POINTER
128	select FUNCTION_ALIGNMENT_4B
129	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
130	select GENERIC_ALLOCATOR
131	select GENERIC_ARCH_TOPOLOGY
132	select GENERIC_CLOCKEVENTS_BROADCAST
133	select GENERIC_CPU_AUTOPROBE
134	select GENERIC_CPU_VULNERABILITIES
135	select GENERIC_EARLY_IOREMAP
136	select GENERIC_IDLE_POLL_SETUP
137	select GENERIC_IOREMAP
138	select GENERIC_IRQ_IPI
139	select GENERIC_IRQ_PROBE
140	select GENERIC_IRQ_SHOW
141	select GENERIC_IRQ_SHOW_LEVEL
142	select GENERIC_LIB_DEVMEM_IS_ALLOWED
143	select GENERIC_PCI_IOMAP
144	select GENERIC_PTDUMP
145	select GENERIC_SCHED_CLOCK
146	select GENERIC_SMP_IDLE_THREAD
147	select GENERIC_TIME_VSYSCALL
148	select GENERIC_GETTIMEOFDAY
149	select GENERIC_VDSO_TIME_NS
150	select HARDIRQS_SW_RESEND
151	select HAS_IOPORT
152	select HAVE_MOVE_PMD
153	select HAVE_MOVE_PUD
154	select HAVE_PCI
155	select HAVE_ACPI_APEI if (ACPI && EFI)
156	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
157	select HAVE_ARCH_AUDITSYSCALL
158	select HAVE_ARCH_BITREVERSE
159	select HAVE_ARCH_COMPILER_H
160	select HAVE_ARCH_HUGE_VMALLOC
161	select HAVE_ARCH_HUGE_VMAP
162	select HAVE_ARCH_JUMP_LABEL
163	select HAVE_ARCH_JUMP_LABEL_RELATIVE
164	select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
165	select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
166	select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
167	select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
168	# Some instrumentation may be unsound, hence EXPERT
169	select HAVE_ARCH_KCSAN if EXPERT
170	select HAVE_ARCH_KFENCE
171	select HAVE_ARCH_KGDB
172	select HAVE_ARCH_MMAP_RND_BITS
173	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
174	select HAVE_ARCH_PREL32_RELOCATIONS
175	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
176	select HAVE_ARCH_SECCOMP_FILTER
177	select HAVE_ARCH_STACKLEAK
178	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
179	select HAVE_ARCH_TRACEHOOK
180	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
181	select HAVE_ARCH_VMAP_STACK
182	select HAVE_ARM_SMCCC
183	select HAVE_ASM_MODVERSIONS
184	select HAVE_EBPF_JIT
185	select HAVE_C_RECORDMCOUNT
186	select HAVE_CMPXCHG_DOUBLE
187	select HAVE_CMPXCHG_LOCAL
188	select HAVE_CONTEXT_TRACKING_USER
189	select HAVE_DEBUG_KMEMLEAK
190	select HAVE_DMA_CONTIGUOUS
191	select HAVE_DYNAMIC_FTRACE
192	select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
193		if $(cc-option,-fpatchable-function-entry=2)
194	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \
195		if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS
196	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
197		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG && \
198		    !CC_OPTIMIZE_FOR_SIZE)
199	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
200		if DYNAMIC_FTRACE_WITH_ARGS
201	select HAVE_SAMPLE_FTRACE_DIRECT
202	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
203	select HAVE_EFFICIENT_UNALIGNED_ACCESS
204	select HAVE_FAST_GUP
205	select HAVE_FTRACE_MCOUNT_RECORD
206	select HAVE_FUNCTION_TRACER
207	select HAVE_FUNCTION_ERROR_INJECTION
208	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
209	select HAVE_FUNCTION_GRAPH_TRACER
210	select HAVE_GCC_PLUGINS
211	select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \
212		HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI
213	select HAVE_HW_BREAKPOINT if PERF_EVENTS
214	select HAVE_IOREMAP_PROT
215	select HAVE_IRQ_TIME_ACCOUNTING
216	select HAVE_KVM
217	select HAVE_MOD_ARCH_SPECIFIC
218	select HAVE_NMI
219	select HAVE_PERF_EVENTS
220	select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI
221	select HAVE_PERF_REGS
222	select HAVE_PERF_USER_STACK_DUMP
223	select HAVE_PREEMPT_DYNAMIC_KEY
224	select HAVE_REGS_AND_STACK_ACCESS_API
225	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
226	select HAVE_FUNCTION_ARG_ACCESS_API
227	select MMU_GATHER_RCU_TABLE_FREE
228	select HAVE_RSEQ
229	select HAVE_STACKPROTECTOR
230	select HAVE_SYSCALL_TRACEPOINTS
231	select HAVE_KPROBES
232	select HAVE_KRETPROBES
233	select HAVE_GENERIC_VDSO
234	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
235	select IRQ_DOMAIN
236	select IRQ_FORCED_THREADING
237	select KASAN_VMALLOC if KASAN
238	select LOCK_MM_AND_FIND_VMA
239	select MODULES_USE_ELF_RELA
240	select NEED_DMA_MAP_STATE
241	select NEED_SG_DMA_LENGTH
242	select OF
243	select OF_EARLY_FLATTREE
244	select PCI_DOMAINS_GENERIC if PCI
245	select PCI_ECAM if (ACPI && PCI)
246	select PCI_SYSCALL if PCI
247	select POWER_RESET
248	select POWER_SUPPLY
249	select SPARSE_IRQ
250	select SWIOTLB
251	select SYSCTL_EXCEPTION_TRACE
252	select THREAD_INFO_IN_TASK
253	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
254	select TRACE_IRQFLAGS_SUPPORT
255	select TRACE_IRQFLAGS_NMI_SUPPORT
256	select HAVE_SOFTIRQ_ON_OWN_STACK
257	help
258	  ARM 64-bit (AArch64) Linux support.
259
260config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
261	def_bool CC_IS_CLANG
262	# https://github.com/ClangBuiltLinux/linux/issues/1507
263	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
264	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
265
266config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
267	def_bool CC_IS_GCC
268	depends on $(cc-option,-fpatchable-function-entry=2)
269	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
270
271config 64BIT
272	def_bool y
273
274config MMU
275	def_bool y
276
277config ARM64_PAGE_SHIFT
278	int
279	default 16 if ARM64_64K_PAGES
280	default 14 if ARM64_16K_PAGES
281	default 12
282
283config ARM64_CONT_PTE_SHIFT
284	int
285	default 5 if ARM64_64K_PAGES
286	default 7 if ARM64_16K_PAGES
287	default 4
288
289config ARM64_CONT_PMD_SHIFT
290	int
291	default 5 if ARM64_64K_PAGES
292	default 5 if ARM64_16K_PAGES
293	default 4
294
295config ARCH_MMAP_RND_BITS_MIN
296	default 14 if ARM64_64K_PAGES
297	default 16 if ARM64_16K_PAGES
298	default 18
299
300# max bits determined by the following formula:
301#  VA_BITS - PAGE_SHIFT - 3
302config ARCH_MMAP_RND_BITS_MAX
303	default 19 if ARM64_VA_BITS=36
304	default 24 if ARM64_VA_BITS=39
305	default 27 if ARM64_VA_BITS=42
306	default 30 if ARM64_VA_BITS=47
307	default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
308	default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
309	default 33 if ARM64_VA_BITS=48
310	default 14 if ARM64_64K_PAGES
311	default 16 if ARM64_16K_PAGES
312	default 18
313
314config ARCH_MMAP_RND_COMPAT_BITS_MIN
315	default 7 if ARM64_64K_PAGES
316	default 9 if ARM64_16K_PAGES
317	default 11
318
319config ARCH_MMAP_RND_COMPAT_BITS_MAX
320	default 16
321
322config NO_IOPORT_MAP
323	def_bool y if !PCI
324
325config STACKTRACE_SUPPORT
326	def_bool y
327
328config ILLEGAL_POINTER_VALUE
329	hex
330	default 0xdead000000000000
331
332config LOCKDEP_SUPPORT
333	def_bool y
334
335config GENERIC_BUG
336	def_bool y
337	depends on BUG
338
339config GENERIC_BUG_RELATIVE_POINTERS
340	def_bool y
341	depends on GENERIC_BUG
342
343config GENERIC_HWEIGHT
344	def_bool y
345
346config GENERIC_CSUM
347	def_bool y
348
349config GENERIC_CALIBRATE_DELAY
350	def_bool y
351
352config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
353	def_bool y
354
355config SMP
356	def_bool y
357
358config KERNEL_MODE_NEON
359	def_bool y
360
361config FIX_EARLYCON_MEM
362	def_bool y
363
364config PGTABLE_LEVELS
365	int
366	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
367	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
368	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
369	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
370	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
371	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
372
373config ARCH_SUPPORTS_UPROBES
374	def_bool y
375
376config ARCH_PROC_KCORE_TEXT
377	def_bool y
378
379config BROKEN_GAS_INST
380	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
381
382config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
383	bool
384	# Clang's __builtin_return_adddress() strips the PAC since 12.0.0
385	# https://reviews.llvm.org/D75044
386	default y if CC_IS_CLANG && (CLANG_VERSION >= 120000)
387	# GCC's __builtin_return_address() strips the PAC since 11.1.0,
388	# and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier
389	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891
390	default y if CC_IS_GCC && (GCC_VERSION >= 110100)
391	default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000)
392	default y if CC_IS_GCC && (GCC_VERSION >=  90400) && (GCC_VERSION < 100000)
393	default y if CC_IS_GCC && (GCC_VERSION >=  80500) && (GCC_VERSION <  90000)
394	default n
395
396config KASAN_SHADOW_OFFSET
397	hex
398	depends on KASAN_GENERIC || KASAN_SW_TAGS
399	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
400	default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
401	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
402	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
403	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
404	default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
405	default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
406	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
407	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
408	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
409	default 0xffffffffffffffff
410
411config UNWIND_TABLES
412	bool
413
414source "arch/arm64/Kconfig.platforms"
415
416menu "Kernel Features"
417
418menu "ARM errata workarounds via the alternatives framework"
419
420config AMPERE_ERRATUM_AC03_CPU_38
421        bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics"
422	default y
423	help
424	  This option adds an alternative code sequence to work around Ampere
425	  erratum AC03_CPU_38 on AmpereOne.
426
427	  The affected design reports FEAT_HAFDBS as not implemented in
428	  ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0
429	  as required by the architecture. The unadvertised HAFDBS
430	  implementation suffers from an additional erratum where hardware
431	  A/D updates can occur after a PTE has been marked invalid.
432
433	  The workaround forces KVM to explicitly set VTCR_EL2.HA to 0,
434	  which avoids enabling unadvertised hardware Access Flag management
435	  at stage-2.
436
437	  If unsure, say Y.
438
439config ARM64_WORKAROUND_CLEAN_CACHE
440	bool
441
442config ARM64_ERRATUM_826319
443	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
444	default y
445	select ARM64_WORKAROUND_CLEAN_CACHE
446	help
447	  This option adds an alternative code sequence to work around ARM
448	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
449	  AXI master interface and an L2 cache.
450
451	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
452	  and is unable to accept a certain write via this interface, it will
453	  not progress on read data presented on the read data channel and the
454	  system can deadlock.
455
456	  The workaround promotes data cache clean instructions to
457	  data cache clean-and-invalidate.
458	  Please note that this does not necessarily enable the workaround,
459	  as it depends on the alternative framework, which will only patch
460	  the kernel if an affected CPU is detected.
461
462	  If unsure, say Y.
463
464config ARM64_ERRATUM_827319
465	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
466	default y
467	select ARM64_WORKAROUND_CLEAN_CACHE
468	help
469	  This option adds an alternative code sequence to work around ARM
470	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
471	  master interface and an L2 cache.
472
473	  Under certain conditions this erratum can cause a clean line eviction
474	  to occur at the same time as another transaction to the same address
475	  on the AMBA 5 CHI interface, which can cause data corruption if the
476	  interconnect reorders the two transactions.
477
478	  The workaround promotes data cache clean instructions to
479	  data cache clean-and-invalidate.
480	  Please note that this does not necessarily enable the workaround,
481	  as it depends on the alternative framework, which will only patch
482	  the kernel if an affected CPU is detected.
483
484	  If unsure, say Y.
485
486config ARM64_ERRATUM_824069
487	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
488	default y
489	select ARM64_WORKAROUND_CLEAN_CACHE
490	help
491	  This option adds an alternative code sequence to work around ARM
492	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
493	  to a coherent interconnect.
494
495	  If a Cortex-A53 processor is executing a store or prefetch for
496	  write instruction at the same time as a processor in another
497	  cluster is executing a cache maintenance operation to the same
498	  address, then this erratum might cause a clean cache line to be
499	  incorrectly marked as dirty.
500
501	  The workaround promotes data cache clean instructions to
502	  data cache clean-and-invalidate.
503	  Please note that this option does not necessarily enable the
504	  workaround, as it depends on the alternative framework, which will
505	  only patch the kernel if an affected CPU is detected.
506
507	  If unsure, say Y.
508
509config ARM64_ERRATUM_819472
510	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
511	default y
512	select ARM64_WORKAROUND_CLEAN_CACHE
513	help
514	  This option adds an alternative code sequence to work around ARM
515	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
516	  present when it is connected to a coherent interconnect.
517
518	  If the processor is executing a load and store exclusive sequence at
519	  the same time as a processor in another cluster is executing a cache
520	  maintenance operation to the same address, then this erratum might
521	  cause data corruption.
522
523	  The workaround promotes data cache clean instructions to
524	  data cache clean-and-invalidate.
525	  Please note that this does not necessarily enable the workaround,
526	  as it depends on the alternative framework, which will only patch
527	  the kernel if an affected CPU is detected.
528
529	  If unsure, say Y.
530
531config ARM64_ERRATUM_832075
532	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
533	default y
534	help
535	  This option adds an alternative code sequence to work around ARM
536	  erratum 832075 on Cortex-A57 parts up to r1p2.
537
538	  Affected Cortex-A57 parts might deadlock when exclusive load/store
539	  instructions to Write-Back memory are mixed with Device loads.
540
541	  The workaround is to promote device loads to use Load-Acquire
542	  semantics.
543	  Please note that this does not necessarily enable the workaround,
544	  as it depends on the alternative framework, which will only patch
545	  the kernel if an affected CPU is detected.
546
547	  If unsure, say Y.
548
549config ARM64_ERRATUM_834220
550	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
551	depends on KVM
552	default y
553	help
554	  This option adds an alternative code sequence to work around ARM
555	  erratum 834220 on Cortex-A57 parts up to r1p2.
556
557	  Affected Cortex-A57 parts might report a Stage 2 translation
558	  fault as the result of a Stage 1 fault for load crossing a
559	  page boundary when there is a permission or device memory
560	  alignment fault at Stage 1 and a translation fault at Stage 2.
561
562	  The workaround is to verify that the Stage 1 translation
563	  doesn't generate a fault before handling the Stage 2 fault.
564	  Please note that this does not necessarily enable the workaround,
565	  as it depends on the alternative framework, which will only patch
566	  the kernel if an affected CPU is detected.
567
568	  If unsure, say Y.
569
570config ARM64_ERRATUM_1742098
571	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
572	depends on COMPAT
573	default y
574	help
575	  This option removes the AES hwcap for aarch32 user-space to
576	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
577
578	  Affected parts may corrupt the AES state if an interrupt is
579	  taken between a pair of AES instructions. These instructions
580	  are only present if the cryptography extensions are present.
581	  All software should have a fallback implementation for CPUs
582	  that don't implement the cryptography extensions.
583
584	  If unsure, say Y.
585
586config ARM64_ERRATUM_845719
587	bool "Cortex-A53: 845719: a load might read incorrect data"
588	depends on COMPAT
589	default y
590	help
591	  This option adds an alternative code sequence to work around ARM
592	  erratum 845719 on Cortex-A53 parts up to r0p4.
593
594	  When running a compat (AArch32) userspace on an affected Cortex-A53
595	  part, a load at EL0 from a virtual address that matches the bottom 32
596	  bits of the virtual address used by a recent load at (AArch64) EL1
597	  might return incorrect data.
598
599	  The workaround is to write the contextidr_el1 register on exception
600	  return to a 32-bit task.
601	  Please note that this does not necessarily enable the workaround,
602	  as it depends on the alternative framework, which will only patch
603	  the kernel if an affected CPU is detected.
604
605	  If unsure, say Y.
606
607config ARM64_ERRATUM_843419
608	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
609	default y
610	help
611	  This option links the kernel with '--fix-cortex-a53-843419' and
612	  enables PLT support to replace certain ADRP instructions, which can
613	  cause subsequent memory accesses to use an incorrect address on
614	  Cortex-A53 parts up to r0p4.
615
616	  If unsure, say Y.
617
618config ARM64_LD_HAS_FIX_ERRATUM_843419
619	def_bool $(ld-option,--fix-cortex-a53-843419)
620
621config ARM64_ERRATUM_1024718
622	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
623	default y
624	help
625	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
626
627	  Affected Cortex-A55 cores (all revisions) could cause incorrect
628	  update of the hardware dirty bit when the DBM/AP bits are updated
629	  without a break-before-make. The workaround is to disable the usage
630	  of hardware DBM locally on the affected cores. CPUs not affected by
631	  this erratum will continue to use the feature.
632
633	  If unsure, say Y.
634
635config ARM64_ERRATUM_1418040
636	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
637	default y
638	depends on COMPAT
639	help
640	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
641	  errata 1188873 and 1418040.
642
643	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
644	  cause register corruption when accessing the timer registers
645	  from AArch32 userspace.
646
647	  If unsure, say Y.
648
649config ARM64_WORKAROUND_SPECULATIVE_AT
650	bool
651
652config ARM64_ERRATUM_1165522
653	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
654	default y
655	select ARM64_WORKAROUND_SPECULATIVE_AT
656	help
657	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
658
659	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
660	  corrupted TLBs by speculating an AT instruction during a guest
661	  context switch.
662
663	  If unsure, say Y.
664
665config ARM64_ERRATUM_1319367
666	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
667	default y
668	select ARM64_WORKAROUND_SPECULATIVE_AT
669	help
670	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
671	  and A72 erratum 1319367
672
673	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
674	  speculating an AT instruction during a guest context switch.
675
676	  If unsure, say Y.
677
678config ARM64_ERRATUM_1530923
679	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
680	default y
681	select ARM64_WORKAROUND_SPECULATIVE_AT
682	help
683	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
684
685	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
686	  corrupted TLBs by speculating an AT instruction during a guest
687	  context switch.
688
689	  If unsure, say Y.
690
691config ARM64_WORKAROUND_REPEAT_TLBI
692	bool
693
694config ARM64_ERRATUM_2441007
695	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
696	default y
697	select ARM64_WORKAROUND_REPEAT_TLBI
698	help
699	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
700
701	  Under very rare circumstances, affected Cortex-A55 CPUs
702	  may not handle a race between a break-before-make sequence on one
703	  CPU, and another CPU accessing the same page. This could allow a
704	  store to a page that has been unmapped.
705
706	  Work around this by adding the affected CPUs to the list that needs
707	  TLB sequences to be done twice.
708
709	  If unsure, say Y.
710
711config ARM64_ERRATUM_1286807
712	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
713	default y
714	select ARM64_WORKAROUND_REPEAT_TLBI
715	help
716	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
717
718	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
719	  address for a cacheable mapping of a location is being
720	  accessed by a core while another core is remapping the virtual
721	  address to a new physical page using the recommended
722	  break-before-make sequence, then under very rare circumstances
723	  TLBI+DSB completes before a read using the translation being
724	  invalidated has been observed by other observers. The
725	  workaround repeats the TLBI+DSB operation.
726
727config ARM64_ERRATUM_1463225
728	bool "Cortex-A76: Software Step might prevent interrupt recognition"
729	default y
730	help
731	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
732
733	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
734	  of a system call instruction (SVC) can prevent recognition of
735	  subsequent interrupts when software stepping is disabled in the
736	  exception handler of the system call and either kernel debugging
737	  is enabled or VHE is in use.
738
739	  Work around the erratum by triggering a dummy step exception
740	  when handling a system call from a task that is being stepped
741	  in a VHE configuration of the kernel.
742
743	  If unsure, say Y.
744
745config ARM64_ERRATUM_1542419
746	bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
747	default y
748	help
749	  This option adds a workaround for ARM Neoverse-N1 erratum
750	  1542419.
751
752	  Affected Neoverse-N1 cores could execute a stale instruction when
753	  modified by another CPU. The workaround depends on a firmware
754	  counterpart.
755
756	  Workaround the issue by hiding the DIC feature from EL0. This
757	  forces user-space to perform cache maintenance.
758
759	  If unsure, say Y.
760
761config ARM64_ERRATUM_1508412
762	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
763	default y
764	help
765	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
766
767	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
768	  of a store-exclusive or read of PAR_EL1 and a load with device or
769	  non-cacheable memory attributes. The workaround depends on a firmware
770	  counterpart.
771
772	  KVM guests must also have the workaround implemented or they can
773	  deadlock the system.
774
775	  Work around the issue by inserting DMB SY barriers around PAR_EL1
776	  register reads and warning KVM users. The DMB barrier is sufficient
777	  to prevent a speculative PAR_EL1 read.
778
779	  If unsure, say Y.
780
781config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
782	bool
783
784config ARM64_ERRATUM_2051678
785	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
786	default y
787	help
788	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
789	  Affected Cortex-A510 might not respect the ordering rules for
790	  hardware update of the page table's dirty bit. The workaround
791	  is to not enable the feature on affected CPUs.
792
793	  If unsure, say Y.
794
795config ARM64_ERRATUM_2077057
796	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
797	default y
798	help
799	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
800	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
801	  expected, but a Pointer Authentication trap is taken instead. The
802	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
803	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
804
805	  This can only happen when EL2 is stepping EL1.
806
807	  When these conditions occur, the SPSR_EL2 value is unchanged from the
808	  previous guest entry, and can be restored from the in-memory copy.
809
810	  If unsure, say Y.
811
812config ARM64_ERRATUM_2658417
813	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
814	default y
815	help
816	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
817	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
818	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
819	  A510 CPUs are using shared neon hardware. As the sharing is not
820	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
821	  user-space should not be using these instructions.
822
823	  If unsure, say Y.
824
825config ARM64_ERRATUM_2119858
826	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
827	default y
828	depends on CORESIGHT_TRBE
829	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
830	help
831	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
832
833	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
834	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
835	  the event of a WRAP event.
836
837	  Work around the issue by always making sure we move the TRBPTR_EL1 by
838	  256 bytes before enabling the buffer and filling the first 256 bytes of
839	  the buffer with ETM ignore packets upon disabling.
840
841	  If unsure, say Y.
842
843config ARM64_ERRATUM_2139208
844	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
845	default y
846	depends on CORESIGHT_TRBE
847	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
848	help
849	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
850
851	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
852	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
853	  the event of a WRAP event.
854
855	  Work around the issue by always making sure we move the TRBPTR_EL1 by
856	  256 bytes before enabling the buffer and filling the first 256 bytes of
857	  the buffer with ETM ignore packets upon disabling.
858
859	  If unsure, say Y.
860
861config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
862	bool
863
864config ARM64_ERRATUM_2054223
865	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
866	default y
867	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
868	help
869	  Enable workaround for ARM Cortex-A710 erratum 2054223
870
871	  Affected cores may fail to flush the trace data on a TSB instruction, when
872	  the PE is in trace prohibited state. This will cause losing a few bytes
873	  of the trace cached.
874
875	  Workaround is to issue two TSB consecutively on affected cores.
876
877	  If unsure, say Y.
878
879config ARM64_ERRATUM_2067961
880	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
881	default y
882	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
883	help
884	  Enable workaround for ARM Neoverse-N2 erratum 2067961
885
886	  Affected cores may fail to flush the trace data on a TSB instruction, when
887	  the PE is in trace prohibited state. This will cause losing a few bytes
888	  of the trace cached.
889
890	  Workaround is to issue two TSB consecutively on affected cores.
891
892	  If unsure, say Y.
893
894config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
895	bool
896
897config ARM64_ERRATUM_2253138
898	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
899	depends on CORESIGHT_TRBE
900	default y
901	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
902	help
903	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
904
905	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
906	  for TRBE. Under some conditions, the TRBE might generate a write to the next
907	  virtually addressed page following the last page of the TRBE address space
908	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
909
910	  Work around this in the driver by always making sure that there is a
911	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
912
913	  If unsure, say Y.
914
915config ARM64_ERRATUM_2224489
916	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
917	depends on CORESIGHT_TRBE
918	default y
919	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
920	help
921	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
922
923	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
924	  for TRBE. Under some conditions, the TRBE might generate a write to the next
925	  virtually addressed page following the last page of the TRBE address space
926	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
927
928	  Work around this in the driver by always making sure that there is a
929	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
930
931	  If unsure, say Y.
932
933config ARM64_ERRATUM_2441009
934	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
935	default y
936	select ARM64_WORKAROUND_REPEAT_TLBI
937	help
938	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
939
940	  Under very rare circumstances, affected Cortex-A510 CPUs
941	  may not handle a race between a break-before-make sequence on one
942	  CPU, and another CPU accessing the same page. This could allow a
943	  store to a page that has been unmapped.
944
945	  Work around this by adding the affected CPUs to the list that needs
946	  TLB sequences to be done twice.
947
948	  If unsure, say Y.
949
950config ARM64_ERRATUM_2064142
951	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
952	depends on CORESIGHT_TRBE
953	default y
954	help
955	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
956
957	  Affected Cortex-A510 core might fail to write into system registers after the
958	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
959	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
960	  and TRBTRG_EL1 will be ignored and will not be effected.
961
962	  Work around this in the driver by executing TSB CSYNC and DSB after collection
963	  is stopped and before performing a system register write to one of the affected
964	  registers.
965
966	  If unsure, say Y.
967
968config ARM64_ERRATUM_2038923
969	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
970	depends on CORESIGHT_TRBE
971	default y
972	help
973	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
974
975	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
976	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
977	  might be corrupted. This happens after TRBE buffer has been enabled by setting
978	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
979	  execution changes from a context, in which trace is prohibited to one where it
980	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
981	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
982	  the trace buffer state might be corrupted.
983
984	  Work around this in the driver by preventing an inconsistent view of whether the
985	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
986	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
987	  two ISB instructions if no ERET is to take place.
988
989	  If unsure, say Y.
990
991config ARM64_ERRATUM_1902691
992	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
993	depends on CORESIGHT_TRBE
994	default y
995	help
996	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
997
998	  Affected Cortex-A510 core might cause trace data corruption, when being written
999	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
1000	  trace data.
1001
1002	  Work around this problem in the driver by just preventing TRBE initialization on
1003	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
1004	  on such implementations. This will cover the kernel for any firmware that doesn't
1005	  do this already.
1006
1007	  If unsure, say Y.
1008
1009config ARM64_ERRATUM_2457168
1010	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
1011	depends on ARM64_AMU_EXTN
1012	default y
1013	help
1014	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
1015
1016	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
1017	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
1018	  incorrectly giving a significantly higher output value.
1019
1020	  Work around this problem by returning 0 when reading the affected counter in
1021	  key locations that results in disabling all users of this counter. This effect
1022	  is the same to firmware disabling affected counters.
1023
1024	  If unsure, say Y.
1025
1026config ARM64_ERRATUM_2645198
1027	bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1028	default y
1029	help
1030	  This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1031
1032	  If a Cortex-A715 cpu sees a page mapping permissions change from executable
1033	  to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1034	  next instruction abort caused by permission fault.
1035
1036	  Only user-space does executable to non-executable permission transition via
1037	  mprotect() system call. Workaround the problem by doing a break-before-make
1038	  TLB invalidation, for all changes to executable user space mappings.
1039
1040	  If unsure, say Y.
1041
1042config CAVIUM_ERRATUM_22375
1043	bool "Cavium erratum 22375, 24313"
1044	default y
1045	help
1046	  Enable workaround for errata 22375 and 24313.
1047
1048	  This implements two gicv3-its errata workarounds for ThunderX. Both
1049	  with a small impact affecting only ITS table allocation.
1050
1051	    erratum 22375: only alloc 8MB table size
1052	    erratum 24313: ignore memory access type
1053
1054	  The fixes are in ITS initialization and basically ignore memory access
1055	  type and table size provided by the TYPER and BASER registers.
1056
1057	  If unsure, say Y.
1058
1059config CAVIUM_ERRATUM_23144
1060	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1061	depends on NUMA
1062	default y
1063	help
1064	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1065
1066	  If unsure, say Y.
1067
1068config CAVIUM_ERRATUM_23154
1069	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1070	default y
1071	help
1072	  The ThunderX GICv3 implementation requires a modified version for
1073	  reading the IAR status to ensure data synchronization
1074	  (access to icc_iar1_el1 is not sync'ed before and after).
1075
1076	  It also suffers from erratum 38545 (also present on Marvell's
1077	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1078	  spuriously presented to the CPU interface.
1079
1080	  If unsure, say Y.
1081
1082config CAVIUM_ERRATUM_27456
1083	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1084	default y
1085	help
1086	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1087	  instructions may cause the icache to become corrupted if it
1088	  contains data for a non-current ASID.  The fix is to
1089	  invalidate the icache when changing the mm context.
1090
1091	  If unsure, say Y.
1092
1093config CAVIUM_ERRATUM_30115
1094	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1095	default y
1096	help
1097	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1098	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1099	  interrupts in host. Trapping both GICv3 group-0 and group-1
1100	  accesses sidesteps the issue.
1101
1102	  If unsure, say Y.
1103
1104config CAVIUM_TX2_ERRATUM_219
1105	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1106	default y
1107	help
1108	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1109	  TTBR update and the corresponding context synchronizing operation can
1110	  cause a spurious Data Abort to be delivered to any hardware thread in
1111	  the CPU core.
1112
1113	  Work around the issue by avoiding the problematic code sequence and
1114	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1115	  trap handler performs the corresponding register access, skips the
1116	  instruction and ensures context synchronization by virtue of the
1117	  exception return.
1118
1119	  If unsure, say Y.
1120
1121config FUJITSU_ERRATUM_010001
1122	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1123	default y
1124	help
1125	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1126	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1127	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1128	  This fault occurs under a specific hardware condition when a
1129	  load/store instruction performs an address translation using:
1130	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1131	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1132	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1133	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1134
1135	  The workaround is to ensure these bits are clear in TCR_ELx.
1136	  The workaround only affects the Fujitsu-A64FX.
1137
1138	  If unsure, say Y.
1139
1140config HISILICON_ERRATUM_161600802
1141	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1142	default y
1143	help
1144	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1145	  when issued ITS commands such as VMOVP and VMAPP, and requires
1146	  a 128kB offset to be applied to the target address in this commands.
1147
1148	  If unsure, say Y.
1149
1150config QCOM_FALKOR_ERRATUM_1003
1151	bool "Falkor E1003: Incorrect translation due to ASID change"
1152	default y
1153	help
1154	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1155	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1156	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1157	  then only for entries in the walk cache, since the leaf translation
1158	  is unchanged. Work around the erratum by invalidating the walk cache
1159	  entries for the trampoline before entering the kernel proper.
1160
1161config QCOM_FALKOR_ERRATUM_1009
1162	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1163	default y
1164	select ARM64_WORKAROUND_REPEAT_TLBI
1165	help
1166	  On Falkor v1, the CPU may prematurely complete a DSB following a
1167	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1168	  one more time to fix the issue.
1169
1170	  If unsure, say Y.
1171
1172config QCOM_QDF2400_ERRATUM_0065
1173	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1174	default y
1175	help
1176	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1177	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1178	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1179
1180	  If unsure, say Y.
1181
1182config QCOM_FALKOR_ERRATUM_E1041
1183	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1184	default y
1185	help
1186	  Falkor CPU may speculatively fetch instructions from an improper
1187	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1188	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1189
1190	  If unsure, say Y.
1191
1192config NVIDIA_CARMEL_CNP_ERRATUM
1193	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1194	default y
1195	help
1196	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1197	  invalidate shared TLB entries installed by a different core, as it would
1198	  on standard ARM cores.
1199
1200	  If unsure, say Y.
1201
1202config ROCKCHIP_ERRATUM_3588001
1203	bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1204	default y
1205	help
1206	  The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1207	  This means, that its sharability feature may not be used, even though it
1208	  is supported by the IP itself.
1209
1210	  If unsure, say Y.
1211
1212config SOCIONEXT_SYNQUACER_PREITS
1213	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1214	default y
1215	help
1216	  Socionext Synquacer SoCs implement a separate h/w block to generate
1217	  MSI doorbell writes with non-zero values for the device ID.
1218
1219	  If unsure, say Y.
1220
1221endmenu # "ARM errata workarounds via the alternatives framework"
1222
1223choice
1224	prompt "Page size"
1225	default ARM64_4K_PAGES
1226	help
1227	  Page size (translation granule) configuration.
1228
1229config ARM64_4K_PAGES
1230	bool "4KB"
1231	help
1232	  This feature enables 4KB pages support.
1233
1234config ARM64_16K_PAGES
1235	bool "16KB"
1236	help
1237	  The system will use 16KB pages support. AArch32 emulation
1238	  requires applications compiled with 16K (or a multiple of 16K)
1239	  aligned segments.
1240
1241config ARM64_64K_PAGES
1242	bool "64KB"
1243	help
1244	  This feature enables 64KB pages support (4KB by default)
1245	  allowing only two levels of page tables and faster TLB
1246	  look-up. AArch32 emulation requires applications compiled
1247	  with 64K aligned segments.
1248
1249endchoice
1250
1251choice
1252	prompt "Virtual address space size"
1253	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
1254	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
1255	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
1256	help
1257	  Allows choosing one of multiple possible virtual address
1258	  space sizes. The level of translation table is determined by
1259	  a combination of page size and virtual address space size.
1260
1261config ARM64_VA_BITS_36
1262	bool "36-bit" if EXPERT
1263	depends on ARM64_16K_PAGES
1264
1265config ARM64_VA_BITS_39
1266	bool "39-bit"
1267	depends on ARM64_4K_PAGES
1268
1269config ARM64_VA_BITS_42
1270	bool "42-bit"
1271	depends on ARM64_64K_PAGES
1272
1273config ARM64_VA_BITS_47
1274	bool "47-bit"
1275	depends on ARM64_16K_PAGES
1276
1277config ARM64_VA_BITS_48
1278	bool "48-bit"
1279
1280config ARM64_VA_BITS_52
1281	bool "52-bit"
1282	depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
1283	help
1284	  Enable 52-bit virtual addressing for userspace when explicitly
1285	  requested via a hint to mmap(). The kernel will also use 52-bit
1286	  virtual addresses for its own mappings (provided HW support for
1287	  this feature is available, otherwise it reverts to 48-bit).
1288
1289	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1290	  ARMv8.3 Pointer Authentication will result in the PAC being
1291	  reduced from 7 bits to 3 bits, which may have a significant
1292	  impact on its susceptibility to brute-force attacks.
1293
1294	  If unsure, select 48-bit virtual addressing instead.
1295
1296endchoice
1297
1298config ARM64_FORCE_52BIT
1299	bool "Force 52-bit virtual addresses for userspace"
1300	depends on ARM64_VA_BITS_52 && EXPERT
1301	help
1302	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1303	  to maintain compatibility with older software by providing 48-bit VAs
1304	  unless a hint is supplied to mmap.
1305
1306	  This configuration option disables the 48-bit compatibility logic, and
1307	  forces all userspace addresses to be 52-bit on HW that supports it. One
1308	  should only enable this configuration option for stress testing userspace
1309	  memory management code. If unsure say N here.
1310
1311config ARM64_VA_BITS
1312	int
1313	default 36 if ARM64_VA_BITS_36
1314	default 39 if ARM64_VA_BITS_39
1315	default 42 if ARM64_VA_BITS_42
1316	default 47 if ARM64_VA_BITS_47
1317	default 48 if ARM64_VA_BITS_48
1318	default 52 if ARM64_VA_BITS_52
1319
1320choice
1321	prompt "Physical address space size"
1322	default ARM64_PA_BITS_48
1323	help
1324	  Choose the maximum physical address range that the kernel will
1325	  support.
1326
1327config ARM64_PA_BITS_48
1328	bool "48-bit"
1329
1330config ARM64_PA_BITS_52
1331	bool "52-bit (ARMv8.2)"
1332	depends on ARM64_64K_PAGES
1333	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1334	help
1335	  Enable support for a 52-bit physical address space, introduced as
1336	  part of the ARMv8.2-LPA extension.
1337
1338	  With this enabled, the kernel will also continue to work on CPUs that
1339	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1340	  minor performance overhead).
1341
1342endchoice
1343
1344config ARM64_PA_BITS
1345	int
1346	default 48 if ARM64_PA_BITS_48
1347	default 52 if ARM64_PA_BITS_52
1348
1349choice
1350	prompt "Endianness"
1351	default CPU_LITTLE_ENDIAN
1352	help
1353	  Select the endianness of data accesses performed by the CPU. Userspace
1354	  applications will need to be compiled and linked for the endianness
1355	  that is selected here.
1356
1357config CPU_BIG_ENDIAN
1358	bool "Build big-endian kernel"
1359	depends on !LD_IS_LLD || LLD_VERSION >= 130000
1360	help
1361	  Say Y if you plan on running a kernel with a big-endian userspace.
1362
1363config CPU_LITTLE_ENDIAN
1364	bool "Build little-endian kernel"
1365	help
1366	  Say Y if you plan on running a kernel with a little-endian userspace.
1367	  This is usually the case for distributions targeting arm64.
1368
1369endchoice
1370
1371config SCHED_MC
1372	bool "Multi-core scheduler support"
1373	help
1374	  Multi-core scheduler support improves the CPU scheduler's decision
1375	  making when dealing with multi-core CPU chips at a cost of slightly
1376	  increased overhead in some places. If unsure say N here.
1377
1378config SCHED_CLUSTER
1379	bool "Cluster scheduler support"
1380	help
1381	  Cluster scheduler support improves the CPU scheduler's decision
1382	  making when dealing with machines that have clusters of CPUs.
1383	  Cluster usually means a couple of CPUs which are placed closely
1384	  by sharing mid-level caches, last-level cache tags or internal
1385	  busses.
1386
1387config SCHED_SMT
1388	bool "SMT scheduler support"
1389	help
1390	  Improves the CPU scheduler's decision making when dealing with
1391	  MultiThreading at a cost of slightly increased overhead in some
1392	  places. If unsure say N here.
1393
1394config NR_CPUS
1395	int "Maximum number of CPUs (2-4096)"
1396	range 2 4096
1397	default "256"
1398
1399config HOTPLUG_CPU
1400	bool "Support for hot-pluggable CPUs"
1401	select GENERIC_IRQ_MIGRATION
1402	help
1403	  Say Y here to experiment with turning CPUs off and on.  CPUs
1404	  can be controlled through /sys/devices/system/cpu.
1405
1406# Common NUMA Features
1407config NUMA
1408	bool "NUMA Memory Allocation and Scheduler Support"
1409	select GENERIC_ARCH_NUMA
1410	select ACPI_NUMA if ACPI
1411	select OF_NUMA
1412	select HAVE_SETUP_PER_CPU_AREA
1413	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1414	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1415	select USE_PERCPU_NUMA_NODE_ID
1416	help
1417	  Enable NUMA (Non-Uniform Memory Access) support.
1418
1419	  The kernel will try to allocate memory used by a CPU on the
1420	  local memory of the CPU and add some more
1421	  NUMA awareness to the kernel.
1422
1423config NODES_SHIFT
1424	int "Maximum NUMA Nodes (as a power of 2)"
1425	range 1 10
1426	default "4"
1427	depends on NUMA
1428	help
1429	  Specify the maximum number of NUMA Nodes available on the target
1430	  system.  Increases memory reserved to accommodate various tables.
1431
1432source "kernel/Kconfig.hz"
1433
1434config ARCH_SPARSEMEM_ENABLE
1435	def_bool y
1436	select SPARSEMEM_VMEMMAP_ENABLE
1437	select SPARSEMEM_VMEMMAP
1438
1439config HW_PERF_EVENTS
1440	def_bool y
1441	depends on ARM_PMU
1442
1443# Supported by clang >= 7.0 or GCC >= 12.0.0
1444config CC_HAVE_SHADOW_CALL_STACK
1445	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1446
1447config PARAVIRT
1448	bool "Enable paravirtualization code"
1449	help
1450	  This changes the kernel so it can modify itself when it is run
1451	  under a hypervisor, potentially improving performance significantly
1452	  over full virtualization.
1453
1454config PARAVIRT_TIME_ACCOUNTING
1455	bool "Paravirtual steal time accounting"
1456	select PARAVIRT
1457	help
1458	  Select this option to enable fine granularity task steal time
1459	  accounting. Time spent executing other tasks in parallel with
1460	  the current vCPU is discounted from the vCPU power. To account for
1461	  that, there can be a small performance impact.
1462
1463	  If in doubt, say N here.
1464
1465config KEXEC
1466	depends on PM_SLEEP_SMP
1467	select KEXEC_CORE
1468	bool "kexec system call"
1469	help
1470	  kexec is a system call that implements the ability to shutdown your
1471	  current kernel, and to start another kernel.  It is like a reboot
1472	  but it is independent of the system firmware.   And like a reboot
1473	  you can start any kernel with it, not just Linux.
1474
1475config KEXEC_FILE
1476	bool "kexec file based system call"
1477	select KEXEC_CORE
1478	select HAVE_IMA_KEXEC if IMA
1479	help
1480	  This is new version of kexec system call. This system call is
1481	  file based and takes file descriptors as system call argument
1482	  for kernel and initramfs as opposed to list of segments as
1483	  accepted by previous system call.
1484
1485config KEXEC_SIG
1486	bool "Verify kernel signature during kexec_file_load() syscall"
1487	depends on KEXEC_FILE
1488	help
1489	  Select this option to verify a signature with loaded kernel
1490	  image. If configured, any attempt of loading a image without
1491	  valid signature will fail.
1492
1493	  In addition to that option, you need to enable signature
1494	  verification for the corresponding kernel image type being
1495	  loaded in order for this to work.
1496
1497config KEXEC_IMAGE_VERIFY_SIG
1498	bool "Enable Image signature verification support"
1499	default y
1500	depends on KEXEC_SIG
1501	depends on EFI && SIGNED_PE_FILE_VERIFICATION
1502	help
1503	  Enable Image signature verification support.
1504
1505comment "Support for PE file signature verification disabled"
1506	depends on KEXEC_SIG
1507	depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
1508
1509config CRASH_DUMP
1510	bool "Build kdump crash kernel"
1511	help
1512	  Generate crash dump after being started by kexec. This should
1513	  be normally only set in special crash dump kernels which are
1514	  loaded in the main kernel with kexec-tools into a specially
1515	  reserved region and then later executed after a crash by
1516	  kdump/kexec.
1517
1518	  For more details see Documentation/admin-guide/kdump/kdump.rst
1519
1520config TRANS_TABLE
1521	def_bool y
1522	depends on HIBERNATION || KEXEC_CORE
1523
1524config XEN_DOM0
1525	def_bool y
1526	depends on XEN
1527
1528config XEN
1529	bool "Xen guest support on ARM64"
1530	depends on ARM64 && OF
1531	select SWIOTLB_XEN
1532	select PARAVIRT
1533	help
1534	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1535
1536# include/linux/mmzone.h requires the following to be true:
1537#
1538#   MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1539#
1540# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1541#
1542#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_ORDER  |  default MAX_ORDER |
1543# ----+-------------------+--------------+-----------------+--------------------+
1544# 4K  |       27          |      12      |       15        |         10         |
1545# 16K |       27          |      14      |       13        |         11         |
1546# 64K |       29          |      16      |       13        |         13         |
1547config ARCH_FORCE_MAX_ORDER
1548	int
1549	default "13" if ARM64_64K_PAGES
1550	default "11" if ARM64_16K_PAGES
1551	default "10"
1552	help
1553	  The kernel page allocator limits the size of maximal physically
1554	  contiguous allocations. The limit is called MAX_ORDER and it
1555	  defines the maximal power of two of number of pages that can be
1556	  allocated as a single contiguous block. This option allows
1557	  overriding the default setting when ability to allocate very
1558	  large blocks of physically contiguous memory is required.
1559
1560	  The maximal size of allocation cannot exceed the size of the
1561	  section, so the value of MAX_ORDER should satisfy
1562
1563	    MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1564
1565	  Don't change if unsure.
1566
1567config UNMAP_KERNEL_AT_EL0
1568	bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
1569	default y
1570	help
1571	  Speculation attacks against some high-performance processors can
1572	  be used to bypass MMU permission checks and leak kernel data to
1573	  userspace. This can be defended against by unmapping the kernel
1574	  when running in userspace, mapping it back in on exception entry
1575	  via a trampoline page in the vector table.
1576
1577	  If unsure, say Y.
1578
1579config MITIGATE_SPECTRE_BRANCH_HISTORY
1580	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1581	default y
1582	help
1583	  Speculation attacks against some high-performance processors can
1584	  make use of branch history to influence future speculation.
1585	  When taking an exception from user-space, a sequence of branches
1586	  or a firmware call overwrites the branch history.
1587
1588config RODATA_FULL_DEFAULT_ENABLED
1589	bool "Apply r/o permissions of VM areas also to their linear aliases"
1590	default y
1591	help
1592	  Apply read-only attributes of VM areas to the linear alias of
1593	  the backing pages as well. This prevents code or read-only data
1594	  from being modified (inadvertently or intentionally) via another
1595	  mapping of the same memory page. This additional enhancement can
1596	  be turned off at runtime by passing rodata=[off|on] (and turned on
1597	  with rodata=full if this option is set to 'n')
1598
1599	  This requires the linear region to be mapped down to pages,
1600	  which may adversely affect performance in some cases.
1601
1602config ARM64_SW_TTBR0_PAN
1603	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1604	help
1605	  Enabling this option prevents the kernel from accessing
1606	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1607	  zeroed area and reserved ASID. The user access routines
1608	  restore the valid TTBR0_EL1 temporarily.
1609
1610config ARM64_TAGGED_ADDR_ABI
1611	bool "Enable the tagged user addresses syscall ABI"
1612	default y
1613	help
1614	  When this option is enabled, user applications can opt in to a
1615	  relaxed ABI via prctl() allowing tagged addresses to be passed
1616	  to system calls as pointer arguments. For details, see
1617	  Documentation/arch/arm64/tagged-address-abi.rst.
1618
1619menuconfig COMPAT
1620	bool "Kernel support for 32-bit EL0"
1621	depends on ARM64_4K_PAGES || EXPERT
1622	select HAVE_UID16
1623	select OLD_SIGSUSPEND3
1624	select COMPAT_OLD_SIGACTION
1625	help
1626	  This option enables support for a 32-bit EL0 running under a 64-bit
1627	  kernel at EL1. AArch32-specific components such as system calls,
1628	  the user helper functions, VFP support and the ptrace interface are
1629	  handled appropriately by the kernel.
1630
1631	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1632	  that you will only be able to execute AArch32 binaries that were compiled
1633	  with page size aligned segments.
1634
1635	  If you want to execute 32-bit userspace applications, say Y.
1636
1637if COMPAT
1638
1639config KUSER_HELPERS
1640	bool "Enable kuser helpers page for 32-bit applications"
1641	default y
1642	help
1643	  Warning: disabling this option may break 32-bit user programs.
1644
1645	  Provide kuser helpers to compat tasks. The kernel provides
1646	  helper code to userspace in read only form at a fixed location
1647	  to allow userspace to be independent of the CPU type fitted to
1648	  the system. This permits binaries to be run on ARMv4 through
1649	  to ARMv8 without modification.
1650
1651	  See Documentation/arch/arm/kernel_user_helpers.rst for details.
1652
1653	  However, the fixed address nature of these helpers can be used
1654	  by ROP (return orientated programming) authors when creating
1655	  exploits.
1656
1657	  If all of the binaries and libraries which run on your platform
1658	  are built specifically for your platform, and make no use of
1659	  these helpers, then you can turn this option off to hinder
1660	  such exploits. However, in that case, if a binary or library
1661	  relying on those helpers is run, it will not function correctly.
1662
1663	  Say N here only if you are absolutely certain that you do not
1664	  need these helpers; otherwise, the safe option is to say Y.
1665
1666config COMPAT_VDSO
1667	bool "Enable vDSO for 32-bit applications"
1668	depends on !CPU_BIG_ENDIAN
1669	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1670	select GENERIC_COMPAT_VDSO
1671	default y
1672	help
1673	  Place in the process address space of 32-bit applications an
1674	  ELF shared object providing fast implementations of gettimeofday
1675	  and clock_gettime.
1676
1677	  You must have a 32-bit build of glibc 2.22 or later for programs
1678	  to seamlessly take advantage of this.
1679
1680config THUMB2_COMPAT_VDSO
1681	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1682	depends on COMPAT_VDSO
1683	default y
1684	help
1685	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1686	  otherwise with '-marm'.
1687
1688config COMPAT_ALIGNMENT_FIXUPS
1689	bool "Fix up misaligned multi-word loads and stores in user space"
1690
1691menuconfig ARMV8_DEPRECATED
1692	bool "Emulate deprecated/obsolete ARMv8 instructions"
1693	depends on SYSCTL
1694	help
1695	  Legacy software support may require certain instructions
1696	  that have been deprecated or obsoleted in the architecture.
1697
1698	  Enable this config to enable selective emulation of these
1699	  features.
1700
1701	  If unsure, say Y
1702
1703if ARMV8_DEPRECATED
1704
1705config SWP_EMULATION
1706	bool "Emulate SWP/SWPB instructions"
1707	help
1708	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1709	  they are always undefined. Say Y here to enable software
1710	  emulation of these instructions for userspace using LDXR/STXR.
1711	  This feature can be controlled at runtime with the abi.swp
1712	  sysctl which is disabled by default.
1713
1714	  In some older versions of glibc [<=2.8] SWP is used during futex
1715	  trylock() operations with the assumption that the code will not
1716	  be preempted. This invalid assumption may be more likely to fail
1717	  with SWP emulation enabled, leading to deadlock of the user
1718	  application.
1719
1720	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1721	  on an external transaction monitoring block called a global
1722	  monitor to maintain update atomicity. If your system does not
1723	  implement a global monitor, this option can cause programs that
1724	  perform SWP operations to uncached memory to deadlock.
1725
1726	  If unsure, say Y
1727
1728config CP15_BARRIER_EMULATION
1729	bool "Emulate CP15 Barrier instructions"
1730	help
1731	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1732	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1733	  strongly recommended to use the ISB, DSB, and DMB
1734	  instructions instead.
1735
1736	  Say Y here to enable software emulation of these
1737	  instructions for AArch32 userspace code. When this option is
1738	  enabled, CP15 barrier usage is traced which can help
1739	  identify software that needs updating. This feature can be
1740	  controlled at runtime with the abi.cp15_barrier sysctl.
1741
1742	  If unsure, say Y
1743
1744config SETEND_EMULATION
1745	bool "Emulate SETEND instruction"
1746	help
1747	  The SETEND instruction alters the data-endianness of the
1748	  AArch32 EL0, and is deprecated in ARMv8.
1749
1750	  Say Y here to enable software emulation of the instruction
1751	  for AArch32 userspace code. This feature can be controlled
1752	  at runtime with the abi.setend sysctl.
1753
1754	  Note: All the cpus on the system must have mixed endian support at EL0
1755	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1756	  endian - is hotplugged in after this feature has been enabled, there could
1757	  be unexpected results in the applications.
1758
1759	  If unsure, say Y
1760endif # ARMV8_DEPRECATED
1761
1762endif # COMPAT
1763
1764menu "ARMv8.1 architectural features"
1765
1766config ARM64_HW_AFDBM
1767	bool "Support for hardware updates of the Access and Dirty page flags"
1768	default y
1769	help
1770	  The ARMv8.1 architecture extensions introduce support for
1771	  hardware updates of the access and dirty information in page
1772	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1773	  capable processors, accesses to pages with PTE_AF cleared will
1774	  set this bit instead of raising an access flag fault.
1775	  Similarly, writes to read-only pages with the DBM bit set will
1776	  clear the read-only bit (AP[2]) instead of raising a
1777	  permission fault.
1778
1779	  Kernels built with this configuration option enabled continue
1780	  to work on pre-ARMv8.1 hardware and the performance impact is
1781	  minimal. If unsure, say Y.
1782
1783config ARM64_PAN
1784	bool "Enable support for Privileged Access Never (PAN)"
1785	default y
1786	help
1787	  Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1788	  prevents the kernel or hypervisor from accessing user-space (EL0)
1789	  memory directly.
1790
1791	  Choosing this option will cause any unprotected (not using
1792	  copy_to_user et al) memory access to fail with a permission fault.
1793
1794	  The feature is detected at runtime, and will remain as a 'nop'
1795	  instruction if the cpu does not implement the feature.
1796
1797config AS_HAS_LDAPR
1798	def_bool $(as-instr,.arch_extension rcpc)
1799
1800config AS_HAS_LSE_ATOMICS
1801	def_bool $(as-instr,.arch_extension lse)
1802
1803config ARM64_LSE_ATOMICS
1804	bool
1805	default ARM64_USE_LSE_ATOMICS
1806	depends on AS_HAS_LSE_ATOMICS
1807
1808config ARM64_USE_LSE_ATOMICS
1809	bool "Atomic instructions"
1810	default y
1811	help
1812	  As part of the Large System Extensions, ARMv8.1 introduces new
1813	  atomic instructions that are designed specifically to scale in
1814	  very large systems.
1815
1816	  Say Y here to make use of these instructions for the in-kernel
1817	  atomic routines. This incurs a small overhead on CPUs that do
1818	  not support these instructions and requires the kernel to be
1819	  built with binutils >= 2.25 in order for the new instructions
1820	  to be used.
1821
1822endmenu # "ARMv8.1 architectural features"
1823
1824menu "ARMv8.2 architectural features"
1825
1826config AS_HAS_ARMV8_2
1827	def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a)
1828
1829config AS_HAS_SHA3
1830	def_bool $(as-instr,.arch armv8.2-a+sha3)
1831
1832config ARM64_PMEM
1833	bool "Enable support for persistent memory"
1834	select ARCH_HAS_PMEM_API
1835	select ARCH_HAS_UACCESS_FLUSHCACHE
1836	help
1837	  Say Y to enable support for the persistent memory API based on the
1838	  ARMv8.2 DCPoP feature.
1839
1840	  The feature is detected at runtime, and the kernel will use DC CVAC
1841	  operations if DC CVAP is not supported (following the behaviour of
1842	  DC CVAP itself if the system does not define a point of persistence).
1843
1844config ARM64_RAS_EXTN
1845	bool "Enable support for RAS CPU Extensions"
1846	default y
1847	help
1848	  CPUs that support the Reliability, Availability and Serviceability
1849	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1850	  errors, classify them and report them to software.
1851
1852	  On CPUs with these extensions system software can use additional
1853	  barriers to determine if faults are pending and read the
1854	  classification from a new set of registers.
1855
1856	  Selecting this feature will allow the kernel to use these barriers
1857	  and access the new registers if the system supports the extension.
1858	  Platform RAS features may additionally depend on firmware support.
1859
1860config ARM64_CNP
1861	bool "Enable support for Common Not Private (CNP) translations"
1862	default y
1863	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1864	help
1865	  Common Not Private (CNP) allows translation table entries to
1866	  be shared between different PEs in the same inner shareable
1867	  domain, so the hardware can use this fact to optimise the
1868	  caching of such entries in the TLB.
1869
1870	  Selecting this option allows the CNP feature to be detected
1871	  at runtime, and does not affect PEs that do not implement
1872	  this feature.
1873
1874endmenu # "ARMv8.2 architectural features"
1875
1876menu "ARMv8.3 architectural features"
1877
1878config ARM64_PTR_AUTH
1879	bool "Enable support for pointer authentication"
1880	default y
1881	help
1882	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1883	  instructions for signing and authenticating pointers against secret
1884	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1885	  and other attacks.
1886
1887	  This option enables these instructions at EL0 (i.e. for userspace).
1888	  Choosing this option will cause the kernel to initialise secret keys
1889	  for each process at exec() time, with these keys being
1890	  context-switched along with the process.
1891
1892	  The feature is detected at runtime. If the feature is not present in
1893	  hardware it will not be advertised to userspace/KVM guest nor will it
1894	  be enabled.
1895
1896	  If the feature is present on the boot CPU but not on a late CPU, then
1897	  the late CPU will be parked. Also, if the boot CPU does not have
1898	  address auth and the late CPU has then the late CPU will still boot
1899	  but with the feature disabled. On such a system, this option should
1900	  not be selected.
1901
1902config ARM64_PTR_AUTH_KERNEL
1903	bool "Use pointer authentication for kernel"
1904	default y
1905	depends on ARM64_PTR_AUTH
1906	depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_ARMV8_3
1907	# Modern compilers insert a .note.gnu.property section note for PAC
1908	# which is only understood by binutils starting with version 2.33.1.
1909	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1910	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1911	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1912	help
1913	  If the compiler supports the -mbranch-protection or
1914	  -msign-return-address flag (e.g. GCC 7 or later), then this option
1915	  will cause the kernel itself to be compiled with return address
1916	  protection. In this case, and if the target hardware is known to
1917	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
1918	  disabled with minimal loss of protection.
1919
1920	  This feature works with FUNCTION_GRAPH_TRACER option only if
1921	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
1922
1923config CC_HAS_BRANCH_PROT_PAC_RET
1924	# GCC 9 or later, clang 8 or later
1925	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1926
1927config CC_HAS_SIGN_RETURN_ADDRESS
1928	# GCC 7, 8
1929	def_bool $(cc-option,-msign-return-address=all)
1930
1931config AS_HAS_ARMV8_3
1932	def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
1933
1934config AS_HAS_CFI_NEGATE_RA_STATE
1935	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1936
1937endmenu # "ARMv8.3 architectural features"
1938
1939menu "ARMv8.4 architectural features"
1940
1941config ARM64_AMU_EXTN
1942	bool "Enable support for the Activity Monitors Unit CPU extension"
1943	default y
1944	help
1945	  The activity monitors extension is an optional extension introduced
1946	  by the ARMv8.4 CPU architecture. This enables support for version 1
1947	  of the activity monitors architecture, AMUv1.
1948
1949	  To enable the use of this extension on CPUs that implement it, say Y.
1950
1951	  Note that for architectural reasons, firmware _must_ implement AMU
1952	  support when running on CPUs that present the activity monitors
1953	  extension. The required support is present in:
1954	    * Version 1.5 and later of the ARM Trusted Firmware
1955
1956	  For kernels that have this configuration enabled but boot with broken
1957	  firmware, you may need to say N here until the firmware is fixed.
1958	  Otherwise you may experience firmware panics or lockups when
1959	  accessing the counter registers. Even if you are not observing these
1960	  symptoms, the values returned by the register reads might not
1961	  correctly reflect reality. Most commonly, the value read will be 0,
1962	  indicating that the counter is not enabled.
1963
1964config AS_HAS_ARMV8_4
1965	def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
1966
1967config ARM64_TLB_RANGE
1968	bool "Enable support for tlbi range feature"
1969	default y
1970	depends on AS_HAS_ARMV8_4
1971	help
1972	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
1973	  range of input addresses.
1974
1975	  The feature introduces new assembly instructions, and they were
1976	  support when binutils >= 2.30.
1977
1978endmenu # "ARMv8.4 architectural features"
1979
1980menu "ARMv8.5 architectural features"
1981
1982config AS_HAS_ARMV8_5
1983	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
1984
1985config ARM64_BTI
1986	bool "Branch Target Identification support"
1987	default y
1988	help
1989	  Branch Target Identification (part of the ARMv8.5 Extensions)
1990	  provides a mechanism to limit the set of locations to which computed
1991	  branch instructions such as BR or BLR can jump.
1992
1993	  To make use of BTI on CPUs that support it, say Y.
1994
1995	  BTI is intended to provide complementary protection to other control
1996	  flow integrity protection mechanisms, such as the Pointer
1997	  authentication mechanism provided as part of the ARMv8.3 Extensions.
1998	  For this reason, it does not make sense to enable this option without
1999	  also enabling support for pointer authentication.  Thus, when
2000	  enabling this option you should also select ARM64_PTR_AUTH=y.
2001
2002	  Userspace binaries must also be specifically compiled to make use of
2003	  this mechanism.  If you say N here or the hardware does not support
2004	  BTI, such binaries can still run, but you get no additional
2005	  enforcement of branch destinations.
2006
2007config ARM64_BTI_KERNEL
2008	bool "Use Branch Target Identification for kernel"
2009	default y
2010	depends on ARM64_BTI
2011	depends on ARM64_PTR_AUTH_KERNEL
2012	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
2013	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
2014	depends on !CC_IS_GCC || GCC_VERSION >= 100100
2015	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
2016	depends on !CC_IS_GCC
2017	# https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9
2018	depends on !CC_IS_CLANG || CLANG_VERSION >= 120000
2019	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2020	help
2021	  Build the kernel with Branch Target Identification annotations
2022	  and enable enforcement of this for kernel code. When this option
2023	  is enabled and the system supports BTI all kernel code including
2024	  modular code must have BTI enabled.
2025
2026config CC_HAS_BRANCH_PROT_PAC_RET_BTI
2027	# GCC 9 or later, clang 8 or later
2028	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2029
2030config ARM64_E0PD
2031	bool "Enable support for E0PD"
2032	default y
2033	help
2034	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
2035	  that EL0 accesses made via TTBR1 always fault in constant time,
2036	  providing similar benefits to KASLR as those provided by KPTI, but
2037	  with lower overhead and without disrupting legitimate access to
2038	  kernel memory such as SPE.
2039
2040	  This option enables E0PD for TTBR1 where available.
2041
2042config ARM64_AS_HAS_MTE
2043	# Initial support for MTE went in binutils 2.32.0, checked with
2044	# ".arch armv8.5-a+memtag" below. However, this was incomplete
2045	# as a late addition to the final architecture spec (LDGM/STGM)
2046	# is only supported in the newer 2.32.x and 2.33 binutils
2047	# versions, hence the extra "stgm" instruction check below.
2048	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2049
2050config ARM64_MTE
2051	bool "Memory Tagging Extension support"
2052	default y
2053	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2054	depends on AS_HAS_ARMV8_5
2055	depends on AS_HAS_LSE_ATOMICS
2056	# Required for tag checking in the uaccess routines
2057	depends on ARM64_PAN
2058	select ARCH_HAS_SUBPAGE_FAULTS
2059	select ARCH_USES_HIGH_VMA_FLAGS
2060	select ARCH_USES_PG_ARCH_X
2061	help
2062	  Memory Tagging (part of the ARMv8.5 Extensions) provides
2063	  architectural support for run-time, always-on detection of
2064	  various classes of memory error to aid with software debugging
2065	  to eliminate vulnerabilities arising from memory-unsafe
2066	  languages.
2067
2068	  This option enables the support for the Memory Tagging
2069	  Extension at EL0 (i.e. for userspace).
2070
2071	  Selecting this option allows the feature to be detected at
2072	  runtime. Any secondary CPU not implementing this feature will
2073	  not be allowed a late bring-up.
2074
2075	  Userspace binaries that want to use this feature must
2076	  explicitly opt in. The mechanism for the userspace is
2077	  described in:
2078
2079	  Documentation/arch/arm64/memory-tagging-extension.rst.
2080
2081endmenu # "ARMv8.5 architectural features"
2082
2083menu "ARMv8.7 architectural features"
2084
2085config ARM64_EPAN
2086	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2087	default y
2088	depends on ARM64_PAN
2089	help
2090	  Enhanced Privileged Access Never (EPAN) allows Privileged
2091	  Access Never to be used with Execute-only mappings.
2092
2093	  The feature is detected at runtime, and will remain disabled
2094	  if the cpu does not implement the feature.
2095endmenu # "ARMv8.7 architectural features"
2096
2097config ARM64_SVE
2098	bool "ARM Scalable Vector Extension support"
2099	default y
2100	help
2101	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2102	  execution state which complements and extends the SIMD functionality
2103	  of the base architecture to support much larger vectors and to enable
2104	  additional vectorisation opportunities.
2105
2106	  To enable use of this extension on CPUs that implement it, say Y.
2107
2108	  On CPUs that support the SVE2 extensions, this option will enable
2109	  those too.
2110
2111	  Note that for architectural reasons, firmware _must_ implement SVE
2112	  support when running on SVE capable hardware.  The required support
2113	  is present in:
2114
2115	    * version 1.5 and later of the ARM Trusted Firmware
2116	    * the AArch64 boot wrapper since commit 5e1261e08abf
2117	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2118
2119	  For other firmware implementations, consult the firmware documentation
2120	  or vendor.
2121
2122	  If you need the kernel to boot on SVE-capable hardware with broken
2123	  firmware, you may need to say N here until you get your firmware
2124	  fixed.  Otherwise, you may experience firmware panics or lockups when
2125	  booting the kernel.  If unsure and you are not observing these
2126	  symptoms, you should assume that it is safe to say Y.
2127
2128config ARM64_SME
2129	bool "ARM Scalable Matrix Extension support"
2130	default y
2131	depends on ARM64_SVE
2132	help
2133	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2134	  execution state which utilises a substantial subset of the SVE
2135	  instruction set, together with the addition of new architectural
2136	  register state capable of holding two dimensional matrix tiles to
2137	  enable various matrix operations.
2138
2139config ARM64_PSEUDO_NMI
2140	bool "Support for NMI-like interrupts"
2141	select ARM_GIC_V3
2142	help
2143	  Adds support for mimicking Non-Maskable Interrupts through the use of
2144	  GIC interrupt priority. This support requires version 3 or later of
2145	  ARM GIC.
2146
2147	  This high priority configuration for interrupts needs to be
2148	  explicitly enabled by setting the kernel parameter
2149	  "irqchip.gicv3_pseudo_nmi" to 1.
2150
2151	  If unsure, say N
2152
2153if ARM64_PSEUDO_NMI
2154config ARM64_DEBUG_PRIORITY_MASKING
2155	bool "Debug interrupt priority masking"
2156	help
2157	  This adds runtime checks to functions enabling/disabling
2158	  interrupts when using priority masking. The additional checks verify
2159	  the validity of ICC_PMR_EL1 when calling concerned functions.
2160
2161	  If unsure, say N
2162endif # ARM64_PSEUDO_NMI
2163
2164config RELOCATABLE
2165	bool "Build a relocatable kernel image" if EXPERT
2166	select ARCH_HAS_RELR
2167	default y
2168	help
2169	  This builds the kernel as a Position Independent Executable (PIE),
2170	  which retains all relocation metadata required to relocate the
2171	  kernel binary at runtime to a different virtual address than the
2172	  address it was linked at.
2173	  Since AArch64 uses the RELA relocation format, this requires a
2174	  relocation pass at runtime even if the kernel is loaded at the
2175	  same address it was linked at.
2176
2177config RANDOMIZE_BASE
2178	bool "Randomize the address of the kernel image"
2179	select RELOCATABLE
2180	help
2181	  Randomizes the virtual address at which the kernel image is
2182	  loaded, as a security feature that deters exploit attempts
2183	  relying on knowledge of the location of kernel internals.
2184
2185	  It is the bootloader's job to provide entropy, by passing a
2186	  random u64 value in /chosen/kaslr-seed at kernel entry.
2187
2188	  When booting via the UEFI stub, it will invoke the firmware's
2189	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2190	  to the kernel proper. In addition, it will randomise the physical
2191	  location of the kernel Image as well.
2192
2193	  If unsure, say N.
2194
2195config RANDOMIZE_MODULE_REGION_FULL
2196	bool "Randomize the module region over a 2 GB range"
2197	depends on RANDOMIZE_BASE
2198	default y
2199	help
2200	  Randomizes the location of the module region inside a 2 GB window
2201	  covering the core kernel. This way, it is less likely for modules
2202	  to leak information about the location of core kernel data structures
2203	  but it does imply that function calls between modules and the core
2204	  kernel will need to be resolved via veneers in the module PLT.
2205
2206	  When this option is not set, the module region will be randomized over
2207	  a limited range that contains the [_stext, _etext] interval of the
2208	  core kernel, so branch relocations are almost always in range unless
2209	  the region is exhausted. In this particular case of region
2210	  exhaustion, modules might be able to fall back to a larger 2GB area.
2211
2212config CC_HAVE_STACKPROTECTOR_SYSREG
2213	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2214
2215config STACKPROTECTOR_PER_TASK
2216	def_bool y
2217	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2218
2219config UNWIND_PATCH_PAC_INTO_SCS
2220	bool "Enable shadow call stack dynamically using code patching"
2221	# needs Clang with https://reviews.llvm.org/D111780 incorporated
2222	depends on CC_IS_CLANG && CLANG_VERSION >= 150000
2223	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2224	depends on SHADOW_CALL_STACK
2225	select UNWIND_TABLES
2226	select DYNAMIC_SCS
2227
2228endmenu # "Kernel Features"
2229
2230menu "Boot options"
2231
2232config ARM64_ACPI_PARKING_PROTOCOL
2233	bool "Enable support for the ARM64 ACPI parking protocol"
2234	depends on ACPI
2235	help
2236	  Enable support for the ARM64 ACPI parking protocol. If disabled
2237	  the kernel will not allow booting through the ARM64 ACPI parking
2238	  protocol even if the corresponding data is present in the ACPI
2239	  MADT table.
2240
2241config CMDLINE
2242	string "Default kernel command string"
2243	default ""
2244	help
2245	  Provide a set of default command-line options at build time by
2246	  entering them here. As a minimum, you should specify the the
2247	  root device (e.g. root=/dev/nfs).
2248
2249choice
2250	prompt "Kernel command line type" if CMDLINE != ""
2251	default CMDLINE_FROM_BOOTLOADER
2252	help
2253	  Choose how the kernel will handle the provided default kernel
2254	  command line string.
2255
2256config CMDLINE_FROM_BOOTLOADER
2257	bool "Use bootloader kernel arguments if available"
2258	help
2259	  Uses the command-line options passed by the boot loader. If
2260	  the boot loader doesn't provide any, the default kernel command
2261	  string provided in CMDLINE will be used.
2262
2263config CMDLINE_FORCE
2264	bool "Always use the default kernel command string"
2265	help
2266	  Always use the default kernel command string, even if the boot
2267	  loader passes other arguments to the kernel.
2268	  This is useful if you cannot or don't want to change the
2269	  command-line options your boot loader passes to the kernel.
2270
2271endchoice
2272
2273config EFI_STUB
2274	bool
2275
2276config EFI
2277	bool "UEFI runtime support"
2278	depends on OF && !CPU_BIG_ENDIAN
2279	depends on KERNEL_MODE_NEON
2280	select ARCH_SUPPORTS_ACPI
2281	select LIBFDT
2282	select UCS2_STRING
2283	select EFI_PARAMS_FROM_FDT
2284	select EFI_RUNTIME_WRAPPERS
2285	select EFI_STUB
2286	select EFI_GENERIC_STUB
2287	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2288	default y
2289	help
2290	  This option provides support for runtime services provided
2291	  by UEFI firmware (such as non-volatile variables, realtime
2292	  clock, and platform reset). A UEFI stub is also provided to
2293	  allow the kernel to be booted as an EFI application. This
2294	  is only useful on systems that have UEFI firmware.
2295
2296config DMI
2297	bool "Enable support for SMBIOS (DMI) tables"
2298	depends on EFI
2299	default y
2300	help
2301	  This enables SMBIOS/DMI feature for systems.
2302
2303	  This option is only useful on systems that have UEFI firmware.
2304	  However, even with this option, the resultant kernel should
2305	  continue to boot on existing non-UEFI platforms.
2306
2307endmenu # "Boot options"
2308
2309menu "Power management options"
2310
2311source "kernel/power/Kconfig"
2312
2313config ARCH_HIBERNATION_POSSIBLE
2314	def_bool y
2315	depends on CPU_PM
2316
2317config ARCH_HIBERNATION_HEADER
2318	def_bool y
2319	depends on HIBERNATION
2320
2321config ARCH_SUSPEND_POSSIBLE
2322	def_bool y
2323
2324endmenu # "Power management options"
2325
2326menu "CPU Power Management"
2327
2328source "drivers/cpuidle/Kconfig"
2329
2330source "drivers/cpufreq/Kconfig"
2331
2332endmenu # "CPU Power Management"
2333
2334source "drivers/acpi/Kconfig"
2335
2336source "arch/arm64/kvm/Kconfig"
2337
2338