xref: /openbmc/linux/arch/arm64/Kconfig (revision 1bdb0fbb)
1# SPDX-License-Identifier: GPL-2.0-only
2config ARM64
3	def_bool y
4	select ACPI_CCA_REQUIRED if ACPI
5	select ACPI_GENERIC_GSI if ACPI
6	select ACPI_GTDT if ACPI
7	select ACPI_IORT if ACPI
8	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
9	select ACPI_MCFG if (ACPI && PCI)
10	select ACPI_SPCR_TABLE if ACPI
11	select ACPI_PPTT if ACPI
12	select ARCH_HAS_DEBUG_WX
13	select ARCH_BINFMT_ELF_EXTRA_PHDRS
14	select ARCH_BINFMT_ELF_STATE
15	select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
16	select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
17	select ARCH_ENABLE_MEMORY_HOTPLUG
18	select ARCH_ENABLE_MEMORY_HOTREMOVE
19	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
20	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
21	select ARCH_HAS_CACHE_LINE_SIZE
22	select ARCH_HAS_CURRENT_STACK_POINTER
23	select ARCH_HAS_DEBUG_VIRTUAL
24	select ARCH_HAS_DEBUG_VM_PGTABLE
25	select ARCH_HAS_DMA_PREP_COHERENT
26	select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
27	select ARCH_HAS_FAST_MULTIPLIER
28	select ARCH_HAS_FORTIFY_SOURCE
29	select ARCH_HAS_GCOV_PROFILE_ALL
30	select ARCH_HAS_GIGANTIC_PAGE
31	select ARCH_HAS_KCOV
32	select ARCH_HAS_KEEPINITRD
33	select ARCH_HAS_MEMBARRIER_SYNC_CORE
34	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
35	select ARCH_HAS_PTE_DEVMAP
36	select ARCH_HAS_PTE_SPECIAL
37	select ARCH_HAS_SETUP_DMA_OPS
38	select ARCH_HAS_SET_DIRECT_MAP
39	select ARCH_HAS_SET_MEMORY
40	select ARCH_STACKWALK
41	select ARCH_HAS_STRICT_KERNEL_RWX
42	select ARCH_HAS_STRICT_MODULE_RWX
43	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
44	select ARCH_HAS_SYNC_DMA_FOR_CPU
45	select ARCH_HAS_SYSCALL_WRAPPER
46	select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
47	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
48	select ARCH_HAS_ZONE_DMA_SET if EXPERT
49	select ARCH_HAVE_ELF_PROT
50	select ARCH_HAVE_NMI_SAFE_CMPXCHG
51	select ARCH_HAVE_TRACE_MMIO_ACCESS
52	select ARCH_INLINE_READ_LOCK if !PREEMPTION
53	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
54	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
55	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
56	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
57	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
58	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
59	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
60	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
61	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
62	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
63	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
64	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
65	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
66	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
67	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
68	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
69	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
70	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
71	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
72	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
73	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
74	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
75	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
76	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
77	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
78	select ARCH_KEEP_MEMBLOCK
79	select ARCH_USE_CMPXCHG_LOCKREF
80	select ARCH_USE_GNU_PROPERTY
81	select ARCH_USE_MEMTEST
82	select ARCH_USE_QUEUED_RWLOCKS
83	select ARCH_USE_QUEUED_SPINLOCKS
84	select ARCH_USE_SYM_ANNOTATIONS
85	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
86	select ARCH_SUPPORTS_HUGETLBFS
87	select ARCH_SUPPORTS_MEMORY_FAILURE
88	select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
89	select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
90	select ARCH_SUPPORTS_LTO_CLANG_THIN
91	select ARCH_SUPPORTS_CFI_CLANG
92	select ARCH_SUPPORTS_ATOMIC_RMW
93	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
94	select ARCH_SUPPORTS_NUMA_BALANCING
95	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
96	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
97	select ARCH_WANT_DEFAULT_BPF_JIT
98	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
99	select ARCH_WANT_FRAME_POINTERS
100	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
101	select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
102	select ARCH_WANT_LD_ORPHAN_WARN
103	select ARCH_WANTS_NO_INSTR
104	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
105	select ARCH_HAS_UBSAN_SANITIZE_ALL
106	select ARM_AMBA
107	select ARM_ARCH_TIMER
108	select ARM_GIC
109	select AUDIT_ARCH_COMPAT_GENERIC
110	select ARM_GIC_V2M if PCI
111	select ARM_GIC_V3
112	select ARM_GIC_V3_ITS if PCI
113	select ARM_PSCI_FW
114	select BUILDTIME_TABLE_SORT
115	select CLONE_BACKWARDS
116	select COMMON_CLK
117	select CPU_PM if (SUSPEND || CPU_IDLE)
118	select CRC32
119	select DCACHE_WORD_ACCESS
120	select DMA_DIRECT_REMAP
121	select EDAC_SUPPORT
122	select FRAME_POINTER
123	select GENERIC_ALLOCATOR
124	select GENERIC_ARCH_TOPOLOGY
125	select GENERIC_CLOCKEVENTS_BROADCAST
126	select GENERIC_CPU_AUTOPROBE
127	select GENERIC_CPU_VULNERABILITIES
128	select GENERIC_EARLY_IOREMAP
129	select GENERIC_IDLE_POLL_SETUP
130	select GENERIC_IOREMAP
131	select GENERIC_IRQ_IPI
132	select GENERIC_IRQ_PROBE
133	select GENERIC_IRQ_SHOW
134	select GENERIC_IRQ_SHOW_LEVEL
135	select GENERIC_LIB_DEVMEM_IS_ALLOWED
136	select GENERIC_PCI_IOMAP
137	select GENERIC_PTDUMP
138	select GENERIC_SCHED_CLOCK
139	select GENERIC_SMP_IDLE_THREAD
140	select GENERIC_TIME_VSYSCALL
141	select GENERIC_GETTIMEOFDAY
142	select GENERIC_VDSO_TIME_NS
143	select HARDIRQS_SW_RESEND
144	select HAVE_MOVE_PMD
145	select HAVE_MOVE_PUD
146	select HAVE_PCI
147	select HAVE_ACPI_APEI if (ACPI && EFI)
148	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
149	select HAVE_ARCH_AUDITSYSCALL
150	select HAVE_ARCH_BITREVERSE
151	select HAVE_ARCH_COMPILER_H
152	select HAVE_ARCH_HUGE_VMAP
153	select HAVE_ARCH_JUMP_LABEL
154	select HAVE_ARCH_JUMP_LABEL_RELATIVE
155	select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
156	select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
157	select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
158	select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
159	# Some instrumentation may be unsound, hence EXPERT
160	select HAVE_ARCH_KCSAN if EXPERT
161	select HAVE_ARCH_KFENCE
162	select HAVE_ARCH_KGDB
163	select HAVE_ARCH_MMAP_RND_BITS
164	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
165	select HAVE_ARCH_PREL32_RELOCATIONS
166	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
167	select HAVE_ARCH_SECCOMP_FILTER
168	select HAVE_ARCH_STACKLEAK
169	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
170	select HAVE_ARCH_TRACEHOOK
171	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
172	select HAVE_ARCH_VMAP_STACK
173	select HAVE_ARM_SMCCC
174	select HAVE_ASM_MODVERSIONS
175	select HAVE_EBPF_JIT
176	select HAVE_C_RECORDMCOUNT
177	select HAVE_CMPXCHG_DOUBLE
178	select HAVE_CMPXCHG_LOCAL
179	select HAVE_CONTEXT_TRACKING_USER
180	select HAVE_DEBUG_KMEMLEAK
181	select HAVE_DMA_CONTIGUOUS
182	select HAVE_DYNAMIC_FTRACE
183	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
184		if DYNAMIC_FTRACE_WITH_REGS
185	select HAVE_EFFICIENT_UNALIGNED_ACCESS
186	select HAVE_FAST_GUP
187	select HAVE_FTRACE_MCOUNT_RECORD
188	select HAVE_FUNCTION_TRACER
189	select HAVE_FUNCTION_ERROR_INJECTION
190	select HAVE_FUNCTION_GRAPH_TRACER
191	select HAVE_GCC_PLUGINS
192	select HAVE_HW_BREAKPOINT if PERF_EVENTS
193	select HAVE_IOREMAP_PROT
194	select HAVE_IRQ_TIME_ACCOUNTING
195	select HAVE_KVM
196	select HAVE_NMI
197	select HAVE_PATA_PLATFORM
198	select HAVE_PERF_EVENTS
199	select HAVE_PERF_REGS
200	select HAVE_PERF_USER_STACK_DUMP
201	select HAVE_PREEMPT_DYNAMIC_KEY
202	select HAVE_REGS_AND_STACK_ACCESS_API
203	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
204	select HAVE_FUNCTION_ARG_ACCESS_API
205	select MMU_GATHER_RCU_TABLE_FREE
206	select HAVE_RSEQ
207	select HAVE_STACKPROTECTOR
208	select HAVE_SYSCALL_TRACEPOINTS
209	select HAVE_KPROBES
210	select HAVE_KRETPROBES
211	select HAVE_GENERIC_VDSO
212	select IOMMU_DMA if IOMMU_SUPPORT
213	select IRQ_DOMAIN
214	select IRQ_FORCED_THREADING
215	select KASAN_VMALLOC if KASAN
216	select MODULES_USE_ELF_RELA
217	select NEED_DMA_MAP_STATE
218	select NEED_SG_DMA_LENGTH
219	select OF
220	select OF_EARLY_FLATTREE
221	select PCI_DOMAINS_GENERIC if PCI
222	select PCI_ECAM if (ACPI && PCI)
223	select PCI_SYSCALL if PCI
224	select POWER_RESET
225	select POWER_SUPPLY
226	select SPARSE_IRQ
227	select SWIOTLB
228	select SYSCTL_EXCEPTION_TRACE
229	select THREAD_INFO_IN_TASK
230	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
231	select TRACE_IRQFLAGS_SUPPORT
232	select TRACE_IRQFLAGS_NMI_SUPPORT
233	help
234	  ARM 64-bit (AArch64) Linux support.
235
236config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS
237	def_bool CC_IS_CLANG
238	# https://github.com/ClangBuiltLinux/linux/issues/1507
239	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
240	select HAVE_DYNAMIC_FTRACE_WITH_REGS
241
242config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS
243	def_bool CC_IS_GCC
244	depends on $(cc-option,-fpatchable-function-entry=2)
245	select HAVE_DYNAMIC_FTRACE_WITH_REGS
246
247config 64BIT
248	def_bool y
249
250config MMU
251	def_bool y
252
253config ARM64_PAGE_SHIFT
254	int
255	default 16 if ARM64_64K_PAGES
256	default 14 if ARM64_16K_PAGES
257	default 12
258
259config ARM64_CONT_PTE_SHIFT
260	int
261	default 5 if ARM64_64K_PAGES
262	default 7 if ARM64_16K_PAGES
263	default 4
264
265config ARM64_CONT_PMD_SHIFT
266	int
267	default 5 if ARM64_64K_PAGES
268	default 5 if ARM64_16K_PAGES
269	default 4
270
271config ARCH_MMAP_RND_BITS_MIN
272	default 14 if ARM64_64K_PAGES
273	default 16 if ARM64_16K_PAGES
274	default 18
275
276# max bits determined by the following formula:
277#  VA_BITS - PAGE_SHIFT - 3
278config ARCH_MMAP_RND_BITS_MAX
279	default 19 if ARM64_VA_BITS=36
280	default 24 if ARM64_VA_BITS=39
281	default 27 if ARM64_VA_BITS=42
282	default 30 if ARM64_VA_BITS=47
283	default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
284	default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
285	default 33 if ARM64_VA_BITS=48
286	default 14 if ARM64_64K_PAGES
287	default 16 if ARM64_16K_PAGES
288	default 18
289
290config ARCH_MMAP_RND_COMPAT_BITS_MIN
291	default 7 if ARM64_64K_PAGES
292	default 9 if ARM64_16K_PAGES
293	default 11
294
295config ARCH_MMAP_RND_COMPAT_BITS_MAX
296	default 16
297
298config NO_IOPORT_MAP
299	def_bool y if !PCI
300
301config STACKTRACE_SUPPORT
302	def_bool y
303
304config ILLEGAL_POINTER_VALUE
305	hex
306	default 0xdead000000000000
307
308config LOCKDEP_SUPPORT
309	def_bool y
310
311config GENERIC_BUG
312	def_bool y
313	depends on BUG
314
315config GENERIC_BUG_RELATIVE_POINTERS
316	def_bool y
317	depends on GENERIC_BUG
318
319config GENERIC_HWEIGHT
320	def_bool y
321
322config GENERIC_CSUM
323	def_bool y
324
325config GENERIC_CALIBRATE_DELAY
326	def_bool y
327
328config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
329	def_bool y
330
331config SMP
332	def_bool y
333
334config KERNEL_MODE_NEON
335	def_bool y
336
337config FIX_EARLYCON_MEM
338	def_bool y
339
340config PGTABLE_LEVELS
341	int
342	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
343	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
344	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
345	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
346	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
347	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
348
349config ARCH_SUPPORTS_UPROBES
350	def_bool y
351
352config ARCH_PROC_KCORE_TEXT
353	def_bool y
354
355config BROKEN_GAS_INST
356	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
357
358config KASAN_SHADOW_OFFSET
359	hex
360	depends on KASAN_GENERIC || KASAN_SW_TAGS
361	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
362	default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
363	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
364	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
365	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
366	default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
367	default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
368	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
369	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
370	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
371	default 0xffffffffffffffff
372
373source "arch/arm64/Kconfig.platforms"
374
375menu "Kernel Features"
376
377menu "ARM errata workarounds via the alternatives framework"
378
379config ARM64_WORKAROUND_CLEAN_CACHE
380	bool
381
382config ARM64_ERRATUM_826319
383	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
384	default y
385	select ARM64_WORKAROUND_CLEAN_CACHE
386	help
387	  This option adds an alternative code sequence to work around ARM
388	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
389	  AXI master interface and an L2 cache.
390
391	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
392	  and is unable to accept a certain write via this interface, it will
393	  not progress on read data presented on the read data channel and the
394	  system can deadlock.
395
396	  The workaround promotes data cache clean instructions to
397	  data cache clean-and-invalidate.
398	  Please note that this does not necessarily enable the workaround,
399	  as it depends on the alternative framework, which will only patch
400	  the kernel if an affected CPU is detected.
401
402	  If unsure, say Y.
403
404config ARM64_ERRATUM_827319
405	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
406	default y
407	select ARM64_WORKAROUND_CLEAN_CACHE
408	help
409	  This option adds an alternative code sequence to work around ARM
410	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
411	  master interface and an L2 cache.
412
413	  Under certain conditions this erratum can cause a clean line eviction
414	  to occur at the same time as another transaction to the same address
415	  on the AMBA 5 CHI interface, which can cause data corruption if the
416	  interconnect reorders the two transactions.
417
418	  The workaround promotes data cache clean instructions to
419	  data cache clean-and-invalidate.
420	  Please note that this does not necessarily enable the workaround,
421	  as it depends on the alternative framework, which will only patch
422	  the kernel if an affected CPU is detected.
423
424	  If unsure, say Y.
425
426config ARM64_ERRATUM_824069
427	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
428	default y
429	select ARM64_WORKAROUND_CLEAN_CACHE
430	help
431	  This option adds an alternative code sequence to work around ARM
432	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
433	  to a coherent interconnect.
434
435	  If a Cortex-A53 processor is executing a store or prefetch for
436	  write instruction at the same time as a processor in another
437	  cluster is executing a cache maintenance operation to the same
438	  address, then this erratum might cause a clean cache line to be
439	  incorrectly marked as dirty.
440
441	  The workaround promotes data cache clean instructions to
442	  data cache clean-and-invalidate.
443	  Please note that this option does not necessarily enable the
444	  workaround, as it depends on the alternative framework, which will
445	  only patch the kernel if an affected CPU is detected.
446
447	  If unsure, say Y.
448
449config ARM64_ERRATUM_819472
450	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
451	default y
452	select ARM64_WORKAROUND_CLEAN_CACHE
453	help
454	  This option adds an alternative code sequence to work around ARM
455	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
456	  present when it is connected to a coherent interconnect.
457
458	  If the processor is executing a load and store exclusive sequence at
459	  the same time as a processor in another cluster is executing a cache
460	  maintenance operation to the same address, then this erratum might
461	  cause data corruption.
462
463	  The workaround promotes data cache clean instructions to
464	  data cache clean-and-invalidate.
465	  Please note that this does not necessarily enable the workaround,
466	  as it depends on the alternative framework, which will only patch
467	  the kernel if an affected CPU is detected.
468
469	  If unsure, say Y.
470
471config ARM64_ERRATUM_832075
472	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
473	default y
474	help
475	  This option adds an alternative code sequence to work around ARM
476	  erratum 832075 on Cortex-A57 parts up to r1p2.
477
478	  Affected Cortex-A57 parts might deadlock when exclusive load/store
479	  instructions to Write-Back memory are mixed with Device loads.
480
481	  The workaround is to promote device loads to use Load-Acquire
482	  semantics.
483	  Please note that this does not necessarily enable the workaround,
484	  as it depends on the alternative framework, which will only patch
485	  the kernel if an affected CPU is detected.
486
487	  If unsure, say Y.
488
489config ARM64_ERRATUM_834220
490	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
491	depends on KVM
492	default y
493	help
494	  This option adds an alternative code sequence to work around ARM
495	  erratum 834220 on Cortex-A57 parts up to r1p2.
496
497	  Affected Cortex-A57 parts might report a Stage 2 translation
498	  fault as the result of a Stage 1 fault for load crossing a
499	  page boundary when there is a permission or device memory
500	  alignment fault at Stage 1 and a translation fault at Stage 2.
501
502	  The workaround is to verify that the Stage 1 translation
503	  doesn't generate a fault before handling the Stage 2 fault.
504	  Please note that this does not necessarily enable the workaround,
505	  as it depends on the alternative framework, which will only patch
506	  the kernel if an affected CPU is detected.
507
508	  If unsure, say Y.
509
510config ARM64_ERRATUM_1742098
511	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
512	depends on COMPAT
513	default y
514	help
515	  This option removes the AES hwcap for aarch32 user-space to
516	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
517
518	  Affected parts may corrupt the AES state if an interrupt is
519	  taken between a pair of AES instructions. These instructions
520	  are only present if the cryptography extensions are present.
521	  All software should have a fallback implementation for CPUs
522	  that don't implement the cryptography extensions.
523
524	  If unsure, say Y.
525
526config ARM64_ERRATUM_845719
527	bool "Cortex-A53: 845719: a load might read incorrect data"
528	depends on COMPAT
529	default y
530	help
531	  This option adds an alternative code sequence to work around ARM
532	  erratum 845719 on Cortex-A53 parts up to r0p4.
533
534	  When running a compat (AArch32) userspace on an affected Cortex-A53
535	  part, a load at EL0 from a virtual address that matches the bottom 32
536	  bits of the virtual address used by a recent load at (AArch64) EL1
537	  might return incorrect data.
538
539	  The workaround is to write the contextidr_el1 register on exception
540	  return to a 32-bit task.
541	  Please note that this does not necessarily enable the workaround,
542	  as it depends on the alternative framework, which will only patch
543	  the kernel if an affected CPU is detected.
544
545	  If unsure, say Y.
546
547config ARM64_ERRATUM_843419
548	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
549	default y
550	select ARM64_MODULE_PLTS if MODULES
551	help
552	  This option links the kernel with '--fix-cortex-a53-843419' and
553	  enables PLT support to replace certain ADRP instructions, which can
554	  cause subsequent memory accesses to use an incorrect address on
555	  Cortex-A53 parts up to r0p4.
556
557	  If unsure, say Y.
558
559config ARM64_LD_HAS_FIX_ERRATUM_843419
560	def_bool $(ld-option,--fix-cortex-a53-843419)
561
562config ARM64_ERRATUM_1024718
563	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
564	default y
565	help
566	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
567
568	  Affected Cortex-A55 cores (all revisions) could cause incorrect
569	  update of the hardware dirty bit when the DBM/AP bits are updated
570	  without a break-before-make. The workaround is to disable the usage
571	  of hardware DBM locally on the affected cores. CPUs not affected by
572	  this erratum will continue to use the feature.
573
574	  If unsure, say Y.
575
576config ARM64_ERRATUM_1418040
577	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
578	default y
579	depends on COMPAT
580	help
581	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
582	  errata 1188873 and 1418040.
583
584	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
585	  cause register corruption when accessing the timer registers
586	  from AArch32 userspace.
587
588	  If unsure, say Y.
589
590config ARM64_WORKAROUND_SPECULATIVE_AT
591	bool
592
593config ARM64_ERRATUM_1165522
594	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
595	default y
596	select ARM64_WORKAROUND_SPECULATIVE_AT
597	help
598	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
599
600	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
601	  corrupted TLBs by speculating an AT instruction during a guest
602	  context switch.
603
604	  If unsure, say Y.
605
606config ARM64_ERRATUM_1319367
607	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
608	default y
609	select ARM64_WORKAROUND_SPECULATIVE_AT
610	help
611	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
612	  and A72 erratum 1319367
613
614	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
615	  speculating an AT instruction during a guest context switch.
616
617	  If unsure, say Y.
618
619config ARM64_ERRATUM_1530923
620	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
621	default y
622	select ARM64_WORKAROUND_SPECULATIVE_AT
623	help
624	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
625
626	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
627	  corrupted TLBs by speculating an AT instruction during a guest
628	  context switch.
629
630	  If unsure, say Y.
631
632config ARM64_WORKAROUND_REPEAT_TLBI
633	bool
634
635config ARM64_ERRATUM_1286807
636	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
637	default y
638	select ARM64_WORKAROUND_REPEAT_TLBI
639	help
640	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
641
642	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
643	  address for a cacheable mapping of a location is being
644	  accessed by a core while another core is remapping the virtual
645	  address to a new physical page using the recommended
646	  break-before-make sequence, then under very rare circumstances
647	  TLBI+DSB completes before a read using the translation being
648	  invalidated has been observed by other observers. The
649	  workaround repeats the TLBI+DSB operation.
650
651config ARM64_ERRATUM_1463225
652	bool "Cortex-A76: Software Step might prevent interrupt recognition"
653	default y
654	help
655	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
656
657	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
658	  of a system call instruction (SVC) can prevent recognition of
659	  subsequent interrupts when software stepping is disabled in the
660	  exception handler of the system call and either kernel debugging
661	  is enabled or VHE is in use.
662
663	  Work around the erratum by triggering a dummy step exception
664	  when handling a system call from a task that is being stepped
665	  in a VHE configuration of the kernel.
666
667	  If unsure, say Y.
668
669config ARM64_ERRATUM_1542419
670	bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
671	default y
672	help
673	  This option adds a workaround for ARM Neoverse-N1 erratum
674	  1542419.
675
676	  Affected Neoverse-N1 cores could execute a stale instruction when
677	  modified by another CPU. The workaround depends on a firmware
678	  counterpart.
679
680	  Workaround the issue by hiding the DIC feature from EL0. This
681	  forces user-space to perform cache maintenance.
682
683	  If unsure, say Y.
684
685config ARM64_ERRATUM_1508412
686	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
687	default y
688	help
689	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
690
691	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
692	  of a store-exclusive or read of PAR_EL1 and a load with device or
693	  non-cacheable memory attributes. The workaround depends on a firmware
694	  counterpart.
695
696	  KVM guests must also have the workaround implemented or they can
697	  deadlock the system.
698
699	  Work around the issue by inserting DMB SY barriers around PAR_EL1
700	  register reads and warning KVM users. The DMB barrier is sufficient
701	  to prevent a speculative PAR_EL1 read.
702
703	  If unsure, say Y.
704
705config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
706	bool
707
708config ARM64_ERRATUM_2051678
709	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
710	default y
711	help
712	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
713	  Affected Cortex-A510 might not respect the ordering rules for
714	  hardware update of the page table's dirty bit. The workaround
715	  is to not enable the feature on affected CPUs.
716
717	  If unsure, say Y.
718
719config ARM64_ERRATUM_2077057
720	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
721	default y
722	help
723	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
724	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
725	  expected, but a Pointer Authentication trap is taken instead. The
726	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
727	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
728
729	  This can only happen when EL2 is stepping EL1.
730
731	  When these conditions occur, the SPSR_EL2 value is unchanged from the
732	  previous guest entry, and can be restored from the in-memory copy.
733
734	  If unsure, say Y.
735
736config ARM64_ERRATUM_2658417
737	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
738	default y
739	help
740	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
741	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
742	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
743	  A510 CPUs are using shared neon hardware. As the sharing is not
744	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
745	  user-space should not be using these instructions.
746
747	  If unsure, say Y.
748
749config ARM64_ERRATUM_2119858
750	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
751	default y
752	depends on CORESIGHT_TRBE
753	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
754	help
755	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
756
757	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
758	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
759	  the event of a WRAP event.
760
761	  Work around the issue by always making sure we move the TRBPTR_EL1 by
762	  256 bytes before enabling the buffer and filling the first 256 bytes of
763	  the buffer with ETM ignore packets upon disabling.
764
765	  If unsure, say Y.
766
767config ARM64_ERRATUM_2139208
768	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
769	default y
770	depends on CORESIGHT_TRBE
771	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
772	help
773	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
774
775	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
776	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
777	  the event of a WRAP event.
778
779	  Work around the issue by always making sure we move the TRBPTR_EL1 by
780	  256 bytes before enabling the buffer and filling the first 256 bytes of
781	  the buffer with ETM ignore packets upon disabling.
782
783	  If unsure, say Y.
784
785config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
786	bool
787
788config ARM64_ERRATUM_2054223
789	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
790	default y
791	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
792	help
793	  Enable workaround for ARM Cortex-A710 erratum 2054223
794
795	  Affected cores may fail to flush the trace data on a TSB instruction, when
796	  the PE is in trace prohibited state. This will cause losing a few bytes
797	  of the trace cached.
798
799	  Workaround is to issue two TSB consecutively on affected cores.
800
801	  If unsure, say Y.
802
803config ARM64_ERRATUM_2067961
804	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
805	default y
806	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
807	help
808	  Enable workaround for ARM Neoverse-N2 erratum 2067961
809
810	  Affected cores may fail to flush the trace data on a TSB instruction, when
811	  the PE is in trace prohibited state. This will cause losing a few bytes
812	  of the trace cached.
813
814	  Workaround is to issue two TSB consecutively on affected cores.
815
816	  If unsure, say Y.
817
818config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
819	bool
820
821config ARM64_ERRATUM_2253138
822	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
823	depends on CORESIGHT_TRBE
824	default y
825	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
826	help
827	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
828
829	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
830	  for TRBE. Under some conditions, the TRBE might generate a write to the next
831	  virtually addressed page following the last page of the TRBE address space
832	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
833
834	  Work around this in the driver by always making sure that there is a
835	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
836
837	  If unsure, say Y.
838
839config ARM64_ERRATUM_2224489
840	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
841	depends on CORESIGHT_TRBE
842	default y
843	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
844	help
845	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
846
847	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
848	  for TRBE. Under some conditions, the TRBE might generate a write to the next
849	  virtually addressed page following the last page of the TRBE address space
850	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
851
852	  Work around this in the driver by always making sure that there is a
853	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
854
855	  If unsure, say Y.
856
857config ARM64_ERRATUM_2441009
858	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
859	default y
860	select ARM64_WORKAROUND_REPEAT_TLBI
861	help
862	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
863
864	  Under very rare circumstances, affected Cortex-A510 CPUs
865	  may not handle a race between a break-before-make sequence on one
866	  CPU, and another CPU accessing the same page. This could allow a
867	  store to a page that has been unmapped.
868
869	  Work around this by adding the affected CPUs to the list that needs
870	  TLB sequences to be done twice.
871
872	  If unsure, say Y.
873
874config ARM64_ERRATUM_2064142
875	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
876	depends on CORESIGHT_TRBE
877	default y
878	help
879	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
880
881	  Affected Cortex-A510 core might fail to write into system registers after the
882	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
883	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
884	  and TRBTRG_EL1 will be ignored and will not be effected.
885
886	  Work around this in the driver by executing TSB CSYNC and DSB after collection
887	  is stopped and before performing a system register write to one of the affected
888	  registers.
889
890	  If unsure, say Y.
891
892config ARM64_ERRATUM_2038923
893	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
894	depends on CORESIGHT_TRBE
895	default y
896	help
897	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
898
899	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
900	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
901	  might be corrupted. This happens after TRBE buffer has been enabled by setting
902	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
903	  execution changes from a context, in which trace is prohibited to one where it
904	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
905	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
906	  the trace buffer state might be corrupted.
907
908	  Work around this in the driver by preventing an inconsistent view of whether the
909	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
910	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
911	  two ISB instructions if no ERET is to take place.
912
913	  If unsure, say Y.
914
915config ARM64_ERRATUM_1902691
916	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
917	depends on CORESIGHT_TRBE
918	default y
919	help
920	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
921
922	  Affected Cortex-A510 core might cause trace data corruption, when being written
923	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
924	  trace data.
925
926	  Work around this problem in the driver by just preventing TRBE initialization on
927	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
928	  on such implementations. This will cover the kernel for any firmware that doesn't
929	  do this already.
930
931	  If unsure, say Y.
932
933config ARM64_ERRATUM_2457168
934	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
935	depends on ARM64_AMU_EXTN
936	default y
937	help
938	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
939
940	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
941	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
942	  incorrectly giving a significantly higher output value.
943
944	  Work around this problem by returning 0 when reading the affected counter in
945	  key locations that results in disabling all users of this counter. This effect
946	  is the same to firmware disabling affected counters.
947
948	  If unsure, say Y.
949
950config CAVIUM_ERRATUM_22375
951	bool "Cavium erratum 22375, 24313"
952	default y
953	help
954	  Enable workaround for errata 22375 and 24313.
955
956	  This implements two gicv3-its errata workarounds for ThunderX. Both
957	  with a small impact affecting only ITS table allocation.
958
959	    erratum 22375: only alloc 8MB table size
960	    erratum 24313: ignore memory access type
961
962	  The fixes are in ITS initialization and basically ignore memory access
963	  type and table size provided by the TYPER and BASER registers.
964
965	  If unsure, say Y.
966
967config CAVIUM_ERRATUM_23144
968	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
969	depends on NUMA
970	default y
971	help
972	  ITS SYNC command hang for cross node io and collections/cpu mapping.
973
974	  If unsure, say Y.
975
976config CAVIUM_ERRATUM_23154
977	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
978	default y
979	help
980	  The ThunderX GICv3 implementation requires a modified version for
981	  reading the IAR status to ensure data synchronization
982	  (access to icc_iar1_el1 is not sync'ed before and after).
983
984	  It also suffers from erratum 38545 (also present on Marvell's
985	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
986	  spuriously presented to the CPU interface.
987
988	  If unsure, say Y.
989
990config CAVIUM_ERRATUM_27456
991	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
992	default y
993	help
994	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
995	  instructions may cause the icache to become corrupted if it
996	  contains data for a non-current ASID.  The fix is to
997	  invalidate the icache when changing the mm context.
998
999	  If unsure, say Y.
1000
1001config CAVIUM_ERRATUM_30115
1002	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1003	default y
1004	help
1005	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1006	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1007	  interrupts in host. Trapping both GICv3 group-0 and group-1
1008	  accesses sidesteps the issue.
1009
1010	  If unsure, say Y.
1011
1012config CAVIUM_TX2_ERRATUM_219
1013	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1014	default y
1015	help
1016	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1017	  TTBR update and the corresponding context synchronizing operation can
1018	  cause a spurious Data Abort to be delivered to any hardware thread in
1019	  the CPU core.
1020
1021	  Work around the issue by avoiding the problematic code sequence and
1022	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1023	  trap handler performs the corresponding register access, skips the
1024	  instruction and ensures context synchronization by virtue of the
1025	  exception return.
1026
1027	  If unsure, say Y.
1028
1029config FUJITSU_ERRATUM_010001
1030	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1031	default y
1032	help
1033	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1034	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1035	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1036	  This fault occurs under a specific hardware condition when a
1037	  load/store instruction performs an address translation using:
1038	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1039	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1040	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1041	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1042
1043	  The workaround is to ensure these bits are clear in TCR_ELx.
1044	  The workaround only affects the Fujitsu-A64FX.
1045
1046	  If unsure, say Y.
1047
1048config HISILICON_ERRATUM_161600802
1049	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1050	default y
1051	help
1052	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1053	  when issued ITS commands such as VMOVP and VMAPP, and requires
1054	  a 128kB offset to be applied to the target address in this commands.
1055
1056	  If unsure, say Y.
1057
1058config QCOM_FALKOR_ERRATUM_1003
1059	bool "Falkor E1003: Incorrect translation due to ASID change"
1060	default y
1061	help
1062	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1063	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1064	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1065	  then only for entries in the walk cache, since the leaf translation
1066	  is unchanged. Work around the erratum by invalidating the walk cache
1067	  entries for the trampoline before entering the kernel proper.
1068
1069config QCOM_FALKOR_ERRATUM_1009
1070	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1071	default y
1072	select ARM64_WORKAROUND_REPEAT_TLBI
1073	help
1074	  On Falkor v1, the CPU may prematurely complete a DSB following a
1075	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1076	  one more time to fix the issue.
1077
1078	  If unsure, say Y.
1079
1080config QCOM_QDF2400_ERRATUM_0065
1081	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1082	default y
1083	help
1084	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1085	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1086	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1087
1088	  If unsure, say Y.
1089
1090config QCOM_FALKOR_ERRATUM_E1041
1091	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1092	default y
1093	help
1094	  Falkor CPU may speculatively fetch instructions from an improper
1095	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1096	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1097
1098	  If unsure, say Y.
1099
1100config NVIDIA_CARMEL_CNP_ERRATUM
1101	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1102	default y
1103	help
1104	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1105	  invalidate shared TLB entries installed by a different core, as it would
1106	  on standard ARM cores.
1107
1108	  If unsure, say Y.
1109
1110config SOCIONEXT_SYNQUACER_PREITS
1111	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1112	default y
1113	help
1114	  Socionext Synquacer SoCs implement a separate h/w block to generate
1115	  MSI doorbell writes with non-zero values for the device ID.
1116
1117	  If unsure, say Y.
1118
1119endmenu # "ARM errata workarounds via the alternatives framework"
1120
1121choice
1122	prompt "Page size"
1123	default ARM64_4K_PAGES
1124	help
1125	  Page size (translation granule) configuration.
1126
1127config ARM64_4K_PAGES
1128	bool "4KB"
1129	help
1130	  This feature enables 4KB pages support.
1131
1132config ARM64_16K_PAGES
1133	bool "16KB"
1134	help
1135	  The system will use 16KB pages support. AArch32 emulation
1136	  requires applications compiled with 16K (or a multiple of 16K)
1137	  aligned segments.
1138
1139config ARM64_64K_PAGES
1140	bool "64KB"
1141	help
1142	  This feature enables 64KB pages support (4KB by default)
1143	  allowing only two levels of page tables and faster TLB
1144	  look-up. AArch32 emulation requires applications compiled
1145	  with 64K aligned segments.
1146
1147endchoice
1148
1149choice
1150	prompt "Virtual address space size"
1151	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
1152	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
1153	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
1154	help
1155	  Allows choosing one of multiple possible virtual address
1156	  space sizes. The level of translation table is determined by
1157	  a combination of page size and virtual address space size.
1158
1159config ARM64_VA_BITS_36
1160	bool "36-bit" if EXPERT
1161	depends on ARM64_16K_PAGES
1162
1163config ARM64_VA_BITS_39
1164	bool "39-bit"
1165	depends on ARM64_4K_PAGES
1166
1167config ARM64_VA_BITS_42
1168	bool "42-bit"
1169	depends on ARM64_64K_PAGES
1170
1171config ARM64_VA_BITS_47
1172	bool "47-bit"
1173	depends on ARM64_16K_PAGES
1174
1175config ARM64_VA_BITS_48
1176	bool "48-bit"
1177
1178config ARM64_VA_BITS_52
1179	bool "52-bit"
1180	depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
1181	help
1182	  Enable 52-bit virtual addressing for userspace when explicitly
1183	  requested via a hint to mmap(). The kernel will also use 52-bit
1184	  virtual addresses for its own mappings (provided HW support for
1185	  this feature is available, otherwise it reverts to 48-bit).
1186
1187	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1188	  ARMv8.3 Pointer Authentication will result in the PAC being
1189	  reduced from 7 bits to 3 bits, which may have a significant
1190	  impact on its susceptibility to brute-force attacks.
1191
1192	  If unsure, select 48-bit virtual addressing instead.
1193
1194endchoice
1195
1196config ARM64_FORCE_52BIT
1197	bool "Force 52-bit virtual addresses for userspace"
1198	depends on ARM64_VA_BITS_52 && EXPERT
1199	help
1200	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1201	  to maintain compatibility with older software by providing 48-bit VAs
1202	  unless a hint is supplied to mmap.
1203
1204	  This configuration option disables the 48-bit compatibility logic, and
1205	  forces all userspace addresses to be 52-bit on HW that supports it. One
1206	  should only enable this configuration option for stress testing userspace
1207	  memory management code. If unsure say N here.
1208
1209config ARM64_VA_BITS
1210	int
1211	default 36 if ARM64_VA_BITS_36
1212	default 39 if ARM64_VA_BITS_39
1213	default 42 if ARM64_VA_BITS_42
1214	default 47 if ARM64_VA_BITS_47
1215	default 48 if ARM64_VA_BITS_48
1216	default 52 if ARM64_VA_BITS_52
1217
1218choice
1219	prompt "Physical address space size"
1220	default ARM64_PA_BITS_48
1221	help
1222	  Choose the maximum physical address range that the kernel will
1223	  support.
1224
1225config ARM64_PA_BITS_48
1226	bool "48-bit"
1227
1228config ARM64_PA_BITS_52
1229	bool "52-bit (ARMv8.2)"
1230	depends on ARM64_64K_PAGES
1231	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1232	help
1233	  Enable support for a 52-bit physical address space, introduced as
1234	  part of the ARMv8.2-LPA extension.
1235
1236	  With this enabled, the kernel will also continue to work on CPUs that
1237	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1238	  minor performance overhead).
1239
1240endchoice
1241
1242config ARM64_PA_BITS
1243	int
1244	default 48 if ARM64_PA_BITS_48
1245	default 52 if ARM64_PA_BITS_52
1246
1247choice
1248	prompt "Endianness"
1249	default CPU_LITTLE_ENDIAN
1250	help
1251	  Select the endianness of data accesses performed by the CPU. Userspace
1252	  applications will need to be compiled and linked for the endianness
1253	  that is selected here.
1254
1255config CPU_BIG_ENDIAN
1256	bool "Build big-endian kernel"
1257	depends on !LD_IS_LLD || LLD_VERSION >= 130000
1258	help
1259	  Say Y if you plan on running a kernel with a big-endian userspace.
1260
1261config CPU_LITTLE_ENDIAN
1262	bool "Build little-endian kernel"
1263	help
1264	  Say Y if you plan on running a kernel with a little-endian userspace.
1265	  This is usually the case for distributions targeting arm64.
1266
1267endchoice
1268
1269config SCHED_MC
1270	bool "Multi-core scheduler support"
1271	help
1272	  Multi-core scheduler support improves the CPU scheduler's decision
1273	  making when dealing with multi-core CPU chips at a cost of slightly
1274	  increased overhead in some places. If unsure say N here.
1275
1276config SCHED_CLUSTER
1277	bool "Cluster scheduler support"
1278	help
1279	  Cluster scheduler support improves the CPU scheduler's decision
1280	  making when dealing with machines that have clusters of CPUs.
1281	  Cluster usually means a couple of CPUs which are placed closely
1282	  by sharing mid-level caches, last-level cache tags or internal
1283	  busses.
1284
1285config SCHED_SMT
1286	bool "SMT scheduler support"
1287	help
1288	  Improves the CPU scheduler's decision making when dealing with
1289	  MultiThreading at a cost of slightly increased overhead in some
1290	  places. If unsure say N here.
1291
1292config NR_CPUS
1293	int "Maximum number of CPUs (2-4096)"
1294	range 2 4096
1295	default "256"
1296
1297config HOTPLUG_CPU
1298	bool "Support for hot-pluggable CPUs"
1299	select GENERIC_IRQ_MIGRATION
1300	help
1301	  Say Y here to experiment with turning CPUs off and on.  CPUs
1302	  can be controlled through /sys/devices/system/cpu.
1303
1304# Common NUMA Features
1305config NUMA
1306	bool "NUMA Memory Allocation and Scheduler Support"
1307	select GENERIC_ARCH_NUMA
1308	select ACPI_NUMA if ACPI
1309	select OF_NUMA
1310	select HAVE_SETUP_PER_CPU_AREA
1311	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1312	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1313	select USE_PERCPU_NUMA_NODE_ID
1314	help
1315	  Enable NUMA (Non-Uniform Memory Access) support.
1316
1317	  The kernel will try to allocate memory used by a CPU on the
1318	  local memory of the CPU and add some more
1319	  NUMA awareness to the kernel.
1320
1321config NODES_SHIFT
1322	int "Maximum NUMA Nodes (as a power of 2)"
1323	range 1 10
1324	default "4"
1325	depends on NUMA
1326	help
1327	  Specify the maximum number of NUMA Nodes available on the target
1328	  system.  Increases memory reserved to accommodate various tables.
1329
1330source "kernel/Kconfig.hz"
1331
1332config ARCH_SPARSEMEM_ENABLE
1333	def_bool y
1334	select SPARSEMEM_VMEMMAP_ENABLE
1335	select SPARSEMEM_VMEMMAP
1336
1337config HW_PERF_EVENTS
1338	def_bool y
1339	depends on ARM_PMU
1340
1341# Supported by clang >= 7.0 or GCC >= 12.0.0
1342config CC_HAVE_SHADOW_CALL_STACK
1343	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1344
1345config PARAVIRT
1346	bool "Enable paravirtualization code"
1347	help
1348	  This changes the kernel so it can modify itself when it is run
1349	  under a hypervisor, potentially improving performance significantly
1350	  over full virtualization.
1351
1352config PARAVIRT_TIME_ACCOUNTING
1353	bool "Paravirtual steal time accounting"
1354	select PARAVIRT
1355	help
1356	  Select this option to enable fine granularity task steal time
1357	  accounting. Time spent executing other tasks in parallel with
1358	  the current vCPU is discounted from the vCPU power. To account for
1359	  that, there can be a small performance impact.
1360
1361	  If in doubt, say N here.
1362
1363config KEXEC
1364	depends on PM_SLEEP_SMP
1365	select KEXEC_CORE
1366	bool "kexec system call"
1367	help
1368	  kexec is a system call that implements the ability to shutdown your
1369	  current kernel, and to start another kernel.  It is like a reboot
1370	  but it is independent of the system firmware.   And like a reboot
1371	  you can start any kernel with it, not just Linux.
1372
1373config KEXEC_FILE
1374	bool "kexec file based system call"
1375	select KEXEC_CORE
1376	select HAVE_IMA_KEXEC if IMA
1377	help
1378	  This is new version of kexec system call. This system call is
1379	  file based and takes file descriptors as system call argument
1380	  for kernel and initramfs as opposed to list of segments as
1381	  accepted by previous system call.
1382
1383config KEXEC_SIG
1384	bool "Verify kernel signature during kexec_file_load() syscall"
1385	depends on KEXEC_FILE
1386	help
1387	  Select this option to verify a signature with loaded kernel
1388	  image. If configured, any attempt of loading a image without
1389	  valid signature will fail.
1390
1391	  In addition to that option, you need to enable signature
1392	  verification for the corresponding kernel image type being
1393	  loaded in order for this to work.
1394
1395config KEXEC_IMAGE_VERIFY_SIG
1396	bool "Enable Image signature verification support"
1397	default y
1398	depends on KEXEC_SIG
1399	depends on EFI && SIGNED_PE_FILE_VERIFICATION
1400	help
1401	  Enable Image signature verification support.
1402
1403comment "Support for PE file signature verification disabled"
1404	depends on KEXEC_SIG
1405	depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
1406
1407config CRASH_DUMP
1408	bool "Build kdump crash kernel"
1409	help
1410	  Generate crash dump after being started by kexec. This should
1411	  be normally only set in special crash dump kernels which are
1412	  loaded in the main kernel with kexec-tools into a specially
1413	  reserved region and then later executed after a crash by
1414	  kdump/kexec.
1415
1416	  For more details see Documentation/admin-guide/kdump/kdump.rst
1417
1418config TRANS_TABLE
1419	def_bool y
1420	depends on HIBERNATION || KEXEC_CORE
1421
1422config XEN_DOM0
1423	def_bool y
1424	depends on XEN
1425
1426config XEN
1427	bool "Xen guest support on ARM64"
1428	depends on ARM64 && OF
1429	select SWIOTLB_XEN
1430	select PARAVIRT
1431	help
1432	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1433
1434config FORCE_MAX_ZONEORDER
1435	int
1436	default "14" if ARM64_64K_PAGES
1437	default "12" if ARM64_16K_PAGES
1438	default "11"
1439	help
1440	  The kernel memory allocator divides physically contiguous memory
1441	  blocks into "zones", where each zone is a power of two number of
1442	  pages.  This option selects the largest power of two that the kernel
1443	  keeps in the memory allocator.  If you need to allocate very large
1444	  blocks of physically contiguous memory, then you may need to
1445	  increase this value.
1446
1447	  This config option is actually maximum order plus one. For example,
1448	  a value of 11 means that the largest free memory block is 2^10 pages.
1449
1450	  We make sure that we can allocate upto a HugePage size for each configuration.
1451	  Hence we have :
1452		MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
1453
1454	  However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
1455	  4M allocations matching the default size used by generic code.
1456
1457config UNMAP_KERNEL_AT_EL0
1458	bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
1459	default y
1460	help
1461	  Speculation attacks against some high-performance processors can
1462	  be used to bypass MMU permission checks and leak kernel data to
1463	  userspace. This can be defended against by unmapping the kernel
1464	  when running in userspace, mapping it back in on exception entry
1465	  via a trampoline page in the vector table.
1466
1467	  If unsure, say Y.
1468
1469config MITIGATE_SPECTRE_BRANCH_HISTORY
1470	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1471	default y
1472	help
1473	  Speculation attacks against some high-performance processors can
1474	  make use of branch history to influence future speculation.
1475	  When taking an exception from user-space, a sequence of branches
1476	  or a firmware call overwrites the branch history.
1477
1478config RODATA_FULL_DEFAULT_ENABLED
1479	bool "Apply r/o permissions of VM areas also to their linear aliases"
1480	default y
1481	help
1482	  Apply read-only attributes of VM areas to the linear alias of
1483	  the backing pages as well. This prevents code or read-only data
1484	  from being modified (inadvertently or intentionally) via another
1485	  mapping of the same memory page. This additional enhancement can
1486	  be turned off at runtime by passing rodata=[off|on] (and turned on
1487	  with rodata=full if this option is set to 'n')
1488
1489	  This requires the linear region to be mapped down to pages,
1490	  which may adversely affect performance in some cases.
1491
1492config ARM64_SW_TTBR0_PAN
1493	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1494	help
1495	  Enabling this option prevents the kernel from accessing
1496	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1497	  zeroed area and reserved ASID. The user access routines
1498	  restore the valid TTBR0_EL1 temporarily.
1499
1500config ARM64_TAGGED_ADDR_ABI
1501	bool "Enable the tagged user addresses syscall ABI"
1502	default y
1503	help
1504	  When this option is enabled, user applications can opt in to a
1505	  relaxed ABI via prctl() allowing tagged addresses to be passed
1506	  to system calls as pointer arguments. For details, see
1507	  Documentation/arm64/tagged-address-abi.rst.
1508
1509menuconfig COMPAT
1510	bool "Kernel support for 32-bit EL0"
1511	depends on ARM64_4K_PAGES || EXPERT
1512	select HAVE_UID16
1513	select OLD_SIGSUSPEND3
1514	select COMPAT_OLD_SIGACTION
1515	help
1516	  This option enables support for a 32-bit EL0 running under a 64-bit
1517	  kernel at EL1. AArch32-specific components such as system calls,
1518	  the user helper functions, VFP support and the ptrace interface are
1519	  handled appropriately by the kernel.
1520
1521	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1522	  that you will only be able to execute AArch32 binaries that were compiled
1523	  with page size aligned segments.
1524
1525	  If you want to execute 32-bit userspace applications, say Y.
1526
1527if COMPAT
1528
1529config KUSER_HELPERS
1530	bool "Enable kuser helpers page for 32-bit applications"
1531	default y
1532	help
1533	  Warning: disabling this option may break 32-bit user programs.
1534
1535	  Provide kuser helpers to compat tasks. The kernel provides
1536	  helper code to userspace in read only form at a fixed location
1537	  to allow userspace to be independent of the CPU type fitted to
1538	  the system. This permits binaries to be run on ARMv4 through
1539	  to ARMv8 without modification.
1540
1541	  See Documentation/arm/kernel_user_helpers.rst for details.
1542
1543	  However, the fixed address nature of these helpers can be used
1544	  by ROP (return orientated programming) authors when creating
1545	  exploits.
1546
1547	  If all of the binaries and libraries which run on your platform
1548	  are built specifically for your platform, and make no use of
1549	  these helpers, then you can turn this option off to hinder
1550	  such exploits. However, in that case, if a binary or library
1551	  relying on those helpers is run, it will not function correctly.
1552
1553	  Say N here only if you are absolutely certain that you do not
1554	  need these helpers; otherwise, the safe option is to say Y.
1555
1556config COMPAT_VDSO
1557	bool "Enable vDSO for 32-bit applications"
1558	depends on !CPU_BIG_ENDIAN
1559	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1560	select GENERIC_COMPAT_VDSO
1561	default y
1562	help
1563	  Place in the process address space of 32-bit applications an
1564	  ELF shared object providing fast implementations of gettimeofday
1565	  and clock_gettime.
1566
1567	  You must have a 32-bit build of glibc 2.22 or later for programs
1568	  to seamlessly take advantage of this.
1569
1570config THUMB2_COMPAT_VDSO
1571	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1572	depends on COMPAT_VDSO
1573	default y
1574	help
1575	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1576	  otherwise with '-marm'.
1577
1578menuconfig ARMV8_DEPRECATED
1579	bool "Emulate deprecated/obsolete ARMv8 instructions"
1580	depends on SYSCTL
1581	help
1582	  Legacy software support may require certain instructions
1583	  that have been deprecated or obsoleted in the architecture.
1584
1585	  Enable this config to enable selective emulation of these
1586	  features.
1587
1588	  If unsure, say Y
1589
1590if ARMV8_DEPRECATED
1591
1592config SWP_EMULATION
1593	bool "Emulate SWP/SWPB instructions"
1594	help
1595	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1596	  they are always undefined. Say Y here to enable software
1597	  emulation of these instructions for userspace using LDXR/STXR.
1598	  This feature can be controlled at runtime with the abi.swp
1599	  sysctl which is disabled by default.
1600
1601	  In some older versions of glibc [<=2.8] SWP is used during futex
1602	  trylock() operations with the assumption that the code will not
1603	  be preempted. This invalid assumption may be more likely to fail
1604	  with SWP emulation enabled, leading to deadlock of the user
1605	  application.
1606
1607	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1608	  on an external transaction monitoring block called a global
1609	  monitor to maintain update atomicity. If your system does not
1610	  implement a global monitor, this option can cause programs that
1611	  perform SWP operations to uncached memory to deadlock.
1612
1613	  If unsure, say Y
1614
1615config CP15_BARRIER_EMULATION
1616	bool "Emulate CP15 Barrier instructions"
1617	help
1618	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1619	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1620	  strongly recommended to use the ISB, DSB, and DMB
1621	  instructions instead.
1622
1623	  Say Y here to enable software emulation of these
1624	  instructions for AArch32 userspace code. When this option is
1625	  enabled, CP15 barrier usage is traced which can help
1626	  identify software that needs updating. This feature can be
1627	  controlled at runtime with the abi.cp15_barrier sysctl.
1628
1629	  If unsure, say Y
1630
1631config SETEND_EMULATION
1632	bool "Emulate SETEND instruction"
1633	help
1634	  The SETEND instruction alters the data-endianness of the
1635	  AArch32 EL0, and is deprecated in ARMv8.
1636
1637	  Say Y here to enable software emulation of the instruction
1638	  for AArch32 userspace code. This feature can be controlled
1639	  at runtime with the abi.setend sysctl.
1640
1641	  Note: All the cpus on the system must have mixed endian support at EL0
1642	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1643	  endian - is hotplugged in after this feature has been enabled, there could
1644	  be unexpected results in the applications.
1645
1646	  If unsure, say Y
1647endif # ARMV8_DEPRECATED
1648
1649endif # COMPAT
1650
1651menu "ARMv8.1 architectural features"
1652
1653config ARM64_HW_AFDBM
1654	bool "Support for hardware updates of the Access and Dirty page flags"
1655	default y
1656	help
1657	  The ARMv8.1 architecture extensions introduce support for
1658	  hardware updates of the access and dirty information in page
1659	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1660	  capable processors, accesses to pages with PTE_AF cleared will
1661	  set this bit instead of raising an access flag fault.
1662	  Similarly, writes to read-only pages with the DBM bit set will
1663	  clear the read-only bit (AP[2]) instead of raising a
1664	  permission fault.
1665
1666	  Kernels built with this configuration option enabled continue
1667	  to work on pre-ARMv8.1 hardware and the performance impact is
1668	  minimal. If unsure, say Y.
1669
1670config ARM64_PAN
1671	bool "Enable support for Privileged Access Never (PAN)"
1672	default y
1673	help
1674	  Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1675	  prevents the kernel or hypervisor from accessing user-space (EL0)
1676	  memory directly.
1677
1678	  Choosing this option will cause any unprotected (not using
1679	  copy_to_user et al) memory access to fail with a permission fault.
1680
1681	  The feature is detected at runtime, and will remain as a 'nop'
1682	  instruction if the cpu does not implement the feature.
1683
1684config AS_HAS_LDAPR
1685	def_bool $(as-instr,.arch_extension rcpc)
1686
1687config AS_HAS_LSE_ATOMICS
1688	def_bool $(as-instr,.arch_extension lse)
1689
1690config ARM64_LSE_ATOMICS
1691	bool
1692	default ARM64_USE_LSE_ATOMICS
1693	depends on AS_HAS_LSE_ATOMICS
1694
1695config ARM64_USE_LSE_ATOMICS
1696	bool "Atomic instructions"
1697	depends on JUMP_LABEL
1698	default y
1699	help
1700	  As part of the Large System Extensions, ARMv8.1 introduces new
1701	  atomic instructions that are designed specifically to scale in
1702	  very large systems.
1703
1704	  Say Y here to make use of these instructions for the in-kernel
1705	  atomic routines. This incurs a small overhead on CPUs that do
1706	  not support these instructions and requires the kernel to be
1707	  built with binutils >= 2.25 in order for the new instructions
1708	  to be used.
1709
1710endmenu # "ARMv8.1 architectural features"
1711
1712menu "ARMv8.2 architectural features"
1713
1714config AS_HAS_ARMV8_2
1715	def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a)
1716
1717config AS_HAS_SHA3
1718	def_bool $(as-instr,.arch armv8.2-a+sha3)
1719
1720config ARM64_PMEM
1721	bool "Enable support for persistent memory"
1722	select ARCH_HAS_PMEM_API
1723	select ARCH_HAS_UACCESS_FLUSHCACHE
1724	help
1725	  Say Y to enable support for the persistent memory API based on the
1726	  ARMv8.2 DCPoP feature.
1727
1728	  The feature is detected at runtime, and the kernel will use DC CVAC
1729	  operations if DC CVAP is not supported (following the behaviour of
1730	  DC CVAP itself if the system does not define a point of persistence).
1731
1732config ARM64_RAS_EXTN
1733	bool "Enable support for RAS CPU Extensions"
1734	default y
1735	help
1736	  CPUs that support the Reliability, Availability and Serviceability
1737	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1738	  errors, classify them and report them to software.
1739
1740	  On CPUs with these extensions system software can use additional
1741	  barriers to determine if faults are pending and read the
1742	  classification from a new set of registers.
1743
1744	  Selecting this feature will allow the kernel to use these barriers
1745	  and access the new registers if the system supports the extension.
1746	  Platform RAS features may additionally depend on firmware support.
1747
1748config ARM64_CNP
1749	bool "Enable support for Common Not Private (CNP) translations"
1750	default y
1751	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1752	help
1753	  Common Not Private (CNP) allows translation table entries to
1754	  be shared between different PEs in the same inner shareable
1755	  domain, so the hardware can use this fact to optimise the
1756	  caching of such entries in the TLB.
1757
1758	  Selecting this option allows the CNP feature to be detected
1759	  at runtime, and does not affect PEs that do not implement
1760	  this feature.
1761
1762endmenu # "ARMv8.2 architectural features"
1763
1764menu "ARMv8.3 architectural features"
1765
1766config ARM64_PTR_AUTH
1767	bool "Enable support for pointer authentication"
1768	default y
1769	help
1770	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1771	  instructions for signing and authenticating pointers against secret
1772	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1773	  and other attacks.
1774
1775	  This option enables these instructions at EL0 (i.e. for userspace).
1776	  Choosing this option will cause the kernel to initialise secret keys
1777	  for each process at exec() time, with these keys being
1778	  context-switched along with the process.
1779
1780	  The feature is detected at runtime. If the feature is not present in
1781	  hardware it will not be advertised to userspace/KVM guest nor will it
1782	  be enabled.
1783
1784	  If the feature is present on the boot CPU but not on a late CPU, then
1785	  the late CPU will be parked. Also, if the boot CPU does not have
1786	  address auth and the late CPU has then the late CPU will still boot
1787	  but with the feature disabled. On such a system, this option should
1788	  not be selected.
1789
1790config ARM64_PTR_AUTH_KERNEL
1791	bool "Use pointer authentication for kernel"
1792	default y
1793	depends on ARM64_PTR_AUTH
1794	depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_PAC
1795	# Modern compilers insert a .note.gnu.property section note for PAC
1796	# which is only understood by binutils starting with version 2.33.1.
1797	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1798	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1799	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
1800	help
1801	  If the compiler supports the -mbranch-protection or
1802	  -msign-return-address flag (e.g. GCC 7 or later), then this option
1803	  will cause the kernel itself to be compiled with return address
1804	  protection. In this case, and if the target hardware is known to
1805	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
1806	  disabled with minimal loss of protection.
1807
1808	  This feature works with FUNCTION_GRAPH_TRACER option only if
1809	  DYNAMIC_FTRACE_WITH_REGS is enabled.
1810
1811config CC_HAS_BRANCH_PROT_PAC_RET
1812	# GCC 9 or later, clang 8 or later
1813	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1814
1815config CC_HAS_SIGN_RETURN_ADDRESS
1816	# GCC 7, 8
1817	def_bool $(cc-option,-msign-return-address=all)
1818
1819config AS_HAS_PAC
1820	def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
1821
1822config AS_HAS_CFI_NEGATE_RA_STATE
1823	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1824
1825endmenu # "ARMv8.3 architectural features"
1826
1827menu "ARMv8.4 architectural features"
1828
1829config ARM64_AMU_EXTN
1830	bool "Enable support for the Activity Monitors Unit CPU extension"
1831	default y
1832	help
1833	  The activity monitors extension is an optional extension introduced
1834	  by the ARMv8.4 CPU architecture. This enables support for version 1
1835	  of the activity monitors architecture, AMUv1.
1836
1837	  To enable the use of this extension on CPUs that implement it, say Y.
1838
1839	  Note that for architectural reasons, firmware _must_ implement AMU
1840	  support when running on CPUs that present the activity monitors
1841	  extension. The required support is present in:
1842	    * Version 1.5 and later of the ARM Trusted Firmware
1843
1844	  For kernels that have this configuration enabled but boot with broken
1845	  firmware, you may need to say N here until the firmware is fixed.
1846	  Otherwise you may experience firmware panics or lockups when
1847	  accessing the counter registers. Even if you are not observing these
1848	  symptoms, the values returned by the register reads might not
1849	  correctly reflect reality. Most commonly, the value read will be 0,
1850	  indicating that the counter is not enabled.
1851
1852config AS_HAS_ARMV8_4
1853	def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
1854
1855config ARM64_TLB_RANGE
1856	bool "Enable support for tlbi range feature"
1857	default y
1858	depends on AS_HAS_ARMV8_4
1859	help
1860	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
1861	  range of input addresses.
1862
1863	  The feature introduces new assembly instructions, and they were
1864	  support when binutils >= 2.30.
1865
1866endmenu # "ARMv8.4 architectural features"
1867
1868menu "ARMv8.5 architectural features"
1869
1870config AS_HAS_ARMV8_5
1871	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
1872
1873config ARM64_BTI
1874	bool "Branch Target Identification support"
1875	default y
1876	help
1877	  Branch Target Identification (part of the ARMv8.5 Extensions)
1878	  provides a mechanism to limit the set of locations to which computed
1879	  branch instructions such as BR or BLR can jump.
1880
1881	  To make use of BTI on CPUs that support it, say Y.
1882
1883	  BTI is intended to provide complementary protection to other control
1884	  flow integrity protection mechanisms, such as the Pointer
1885	  authentication mechanism provided as part of the ARMv8.3 Extensions.
1886	  For this reason, it does not make sense to enable this option without
1887	  also enabling support for pointer authentication.  Thus, when
1888	  enabling this option you should also select ARM64_PTR_AUTH=y.
1889
1890	  Userspace binaries must also be specifically compiled to make use of
1891	  this mechanism.  If you say N here or the hardware does not support
1892	  BTI, such binaries can still run, but you get no additional
1893	  enforcement of branch destinations.
1894
1895config ARM64_BTI_KERNEL
1896	bool "Use Branch Target Identification for kernel"
1897	default y
1898	depends on ARM64_BTI
1899	depends on ARM64_PTR_AUTH_KERNEL
1900	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
1901	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
1902	depends on !CC_IS_GCC || GCC_VERSION >= 100100
1903	# https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9
1904	depends on !CC_IS_CLANG || CLANG_VERSION >= 120000
1905	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
1906	help
1907	  Build the kernel with Branch Target Identification annotations
1908	  and enable enforcement of this for kernel code. When this option
1909	  is enabled and the system supports BTI all kernel code including
1910	  modular code must have BTI enabled.
1911
1912config CC_HAS_BRANCH_PROT_PAC_RET_BTI
1913	# GCC 9 or later, clang 8 or later
1914	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
1915
1916config ARM64_E0PD
1917	bool "Enable support for E0PD"
1918	default y
1919	help
1920	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
1921	  that EL0 accesses made via TTBR1 always fault in constant time,
1922	  providing similar benefits to KASLR as those provided by KPTI, but
1923	  with lower overhead and without disrupting legitimate access to
1924	  kernel memory such as SPE.
1925
1926	  This option enables E0PD for TTBR1 where available.
1927
1928config ARM64_AS_HAS_MTE
1929	# Initial support for MTE went in binutils 2.32.0, checked with
1930	# ".arch armv8.5-a+memtag" below. However, this was incomplete
1931	# as a late addition to the final architecture spec (LDGM/STGM)
1932	# is only supported in the newer 2.32.x and 2.33 binutils
1933	# versions, hence the extra "stgm" instruction check below.
1934	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
1935
1936config ARM64_MTE
1937	bool "Memory Tagging Extension support"
1938	default y
1939	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
1940	depends on AS_HAS_ARMV8_5
1941	depends on AS_HAS_LSE_ATOMICS
1942	# Required for tag checking in the uaccess routines
1943	depends on ARM64_PAN
1944	select ARCH_HAS_SUBPAGE_FAULTS
1945	select ARCH_USES_HIGH_VMA_FLAGS
1946	help
1947	  Memory Tagging (part of the ARMv8.5 Extensions) provides
1948	  architectural support for run-time, always-on detection of
1949	  various classes of memory error to aid with software debugging
1950	  to eliminate vulnerabilities arising from memory-unsafe
1951	  languages.
1952
1953	  This option enables the support for the Memory Tagging
1954	  Extension at EL0 (i.e. for userspace).
1955
1956	  Selecting this option allows the feature to be detected at
1957	  runtime. Any secondary CPU not implementing this feature will
1958	  not be allowed a late bring-up.
1959
1960	  Userspace binaries that want to use this feature must
1961	  explicitly opt in. The mechanism for the userspace is
1962	  described in:
1963
1964	  Documentation/arm64/memory-tagging-extension.rst.
1965
1966endmenu # "ARMv8.5 architectural features"
1967
1968menu "ARMv8.7 architectural features"
1969
1970config ARM64_EPAN
1971	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
1972	default y
1973	depends on ARM64_PAN
1974	help
1975	  Enhanced Privileged Access Never (EPAN) allows Privileged
1976	  Access Never to be used with Execute-only mappings.
1977
1978	  The feature is detected at runtime, and will remain disabled
1979	  if the cpu does not implement the feature.
1980endmenu # "ARMv8.7 architectural features"
1981
1982config ARM64_SVE
1983	bool "ARM Scalable Vector Extension support"
1984	default y
1985	help
1986	  The Scalable Vector Extension (SVE) is an extension to the AArch64
1987	  execution state which complements and extends the SIMD functionality
1988	  of the base architecture to support much larger vectors and to enable
1989	  additional vectorisation opportunities.
1990
1991	  To enable use of this extension on CPUs that implement it, say Y.
1992
1993	  On CPUs that support the SVE2 extensions, this option will enable
1994	  those too.
1995
1996	  Note that for architectural reasons, firmware _must_ implement SVE
1997	  support when running on SVE capable hardware.  The required support
1998	  is present in:
1999
2000	    * version 1.5 and later of the ARM Trusted Firmware
2001	    * the AArch64 boot wrapper since commit 5e1261e08abf
2002	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2003
2004	  For other firmware implementations, consult the firmware documentation
2005	  or vendor.
2006
2007	  If you need the kernel to boot on SVE-capable hardware with broken
2008	  firmware, you may need to say N here until you get your firmware
2009	  fixed.  Otherwise, you may experience firmware panics or lockups when
2010	  booting the kernel.  If unsure and you are not observing these
2011	  symptoms, you should assume that it is safe to say Y.
2012
2013config ARM64_SME
2014	bool "ARM Scalable Matrix Extension support"
2015	default y
2016	depends on ARM64_SVE
2017	help
2018	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2019	  execution state which utilises a substantial subset of the SVE
2020	  instruction set, together with the addition of new architectural
2021	  register state capable of holding two dimensional matrix tiles to
2022	  enable various matrix operations.
2023
2024config ARM64_MODULE_PLTS
2025	bool "Use PLTs to allow module memory to spill over into vmalloc area"
2026	depends on MODULES
2027	select HAVE_MOD_ARCH_SPECIFIC
2028	help
2029	  Allocate PLTs when loading modules so that jumps and calls whose
2030	  targets are too far away for their relative offsets to be encoded
2031	  in the instructions themselves can be bounced via veneers in the
2032	  module's PLT. This allows modules to be allocated in the generic
2033	  vmalloc area after the dedicated module memory area has been
2034	  exhausted.
2035
2036	  When running with address space randomization (KASLR), the module
2037	  region itself may be too far away for ordinary relative jumps and
2038	  calls, and so in that case, module PLTs are required and cannot be
2039	  disabled.
2040
2041	  Specific errata workaround(s) might also force module PLTs to be
2042	  enabled (ARM64_ERRATUM_843419).
2043
2044config ARM64_PSEUDO_NMI
2045	bool "Support for NMI-like interrupts"
2046	select ARM_GIC_V3
2047	help
2048	  Adds support for mimicking Non-Maskable Interrupts through the use of
2049	  GIC interrupt priority. This support requires version 3 or later of
2050	  ARM GIC.
2051
2052	  This high priority configuration for interrupts needs to be
2053	  explicitly enabled by setting the kernel parameter
2054	  "irqchip.gicv3_pseudo_nmi" to 1.
2055
2056	  If unsure, say N
2057
2058if ARM64_PSEUDO_NMI
2059config ARM64_DEBUG_PRIORITY_MASKING
2060	bool "Debug interrupt priority masking"
2061	help
2062	  This adds runtime checks to functions enabling/disabling
2063	  interrupts when using priority masking. The additional checks verify
2064	  the validity of ICC_PMR_EL1 when calling concerned functions.
2065
2066	  If unsure, say N
2067endif # ARM64_PSEUDO_NMI
2068
2069config RELOCATABLE
2070	bool "Build a relocatable kernel image" if EXPERT
2071	select ARCH_HAS_RELR
2072	default y
2073	help
2074	  This builds the kernel as a Position Independent Executable (PIE),
2075	  which retains all relocation metadata required to relocate the
2076	  kernel binary at runtime to a different virtual address than the
2077	  address it was linked at.
2078	  Since AArch64 uses the RELA relocation format, this requires a
2079	  relocation pass at runtime even if the kernel is loaded at the
2080	  same address it was linked at.
2081
2082config RANDOMIZE_BASE
2083	bool "Randomize the address of the kernel image"
2084	select ARM64_MODULE_PLTS if MODULES
2085	select RELOCATABLE
2086	help
2087	  Randomizes the virtual address at which the kernel image is
2088	  loaded, as a security feature that deters exploit attempts
2089	  relying on knowledge of the location of kernel internals.
2090
2091	  It is the bootloader's job to provide entropy, by passing a
2092	  random u64 value in /chosen/kaslr-seed at kernel entry.
2093
2094	  When booting via the UEFI stub, it will invoke the firmware's
2095	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2096	  to the kernel proper. In addition, it will randomise the physical
2097	  location of the kernel Image as well.
2098
2099	  If unsure, say N.
2100
2101config RANDOMIZE_MODULE_REGION_FULL
2102	bool "Randomize the module region over a 2 GB range"
2103	depends on RANDOMIZE_BASE
2104	default y
2105	help
2106	  Randomizes the location of the module region inside a 2 GB window
2107	  covering the core kernel. This way, it is less likely for modules
2108	  to leak information about the location of core kernel data structures
2109	  but it does imply that function calls between modules and the core
2110	  kernel will need to be resolved via veneers in the module PLT.
2111
2112	  When this option is not set, the module region will be randomized over
2113	  a limited range that contains the [_stext, _etext] interval of the
2114	  core kernel, so branch relocations are almost always in range unless
2115	  ARM64_MODULE_PLTS is enabled and the region is exhausted. In this
2116	  particular case of region exhaustion, modules might be able to fall
2117	  back to a larger 2GB area.
2118
2119config CC_HAVE_STACKPROTECTOR_SYSREG
2120	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2121
2122config STACKPROTECTOR_PER_TASK
2123	def_bool y
2124	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2125
2126# The GPIO number here must be sorted by descending number. In case of
2127# a multiplatform kernel, we just want the highest value required by the
2128# selected platforms.
2129config ARCH_NR_GPIO
2130        int
2131        default 2048 if ARCH_APPLE
2132        default 0
2133        help
2134          Maximum number of GPIOs in the system.
2135
2136          If unsure, leave the default value.
2137
2138endmenu # "Kernel Features"
2139
2140menu "Boot options"
2141
2142config ARM64_ACPI_PARKING_PROTOCOL
2143	bool "Enable support for the ARM64 ACPI parking protocol"
2144	depends on ACPI
2145	help
2146	  Enable support for the ARM64 ACPI parking protocol. If disabled
2147	  the kernel will not allow booting through the ARM64 ACPI parking
2148	  protocol even if the corresponding data is present in the ACPI
2149	  MADT table.
2150
2151config CMDLINE
2152	string "Default kernel command string"
2153	default ""
2154	help
2155	  Provide a set of default command-line options at build time by
2156	  entering them here. As a minimum, you should specify the the
2157	  root device (e.g. root=/dev/nfs).
2158
2159choice
2160	prompt "Kernel command line type" if CMDLINE != ""
2161	default CMDLINE_FROM_BOOTLOADER
2162	help
2163	  Choose how the kernel will handle the provided default kernel
2164	  command line string.
2165
2166config CMDLINE_FROM_BOOTLOADER
2167	bool "Use bootloader kernel arguments if available"
2168	help
2169	  Uses the command-line options passed by the boot loader. If
2170	  the boot loader doesn't provide any, the default kernel command
2171	  string provided in CMDLINE will be used.
2172
2173config CMDLINE_FORCE
2174	bool "Always use the default kernel command string"
2175	help
2176	  Always use the default kernel command string, even if the boot
2177	  loader passes other arguments to the kernel.
2178	  This is useful if you cannot or don't want to change the
2179	  command-line options your boot loader passes to the kernel.
2180
2181endchoice
2182
2183config EFI_STUB
2184	bool
2185
2186config EFI
2187	bool "UEFI runtime support"
2188	depends on OF && !CPU_BIG_ENDIAN
2189	depends on KERNEL_MODE_NEON
2190	select ARCH_SUPPORTS_ACPI
2191	select LIBFDT
2192	select UCS2_STRING
2193	select EFI_PARAMS_FROM_FDT
2194	select EFI_RUNTIME_WRAPPERS
2195	select EFI_STUB
2196	select EFI_GENERIC_STUB
2197	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2198	default y
2199	help
2200	  This option provides support for runtime services provided
2201	  by UEFI firmware (such as non-volatile variables, realtime
2202	  clock, and platform reset). A UEFI stub is also provided to
2203	  allow the kernel to be booted as an EFI application. This
2204	  is only useful on systems that have UEFI firmware.
2205
2206config DMI
2207	bool "Enable support for SMBIOS (DMI) tables"
2208	depends on EFI
2209	default y
2210	help
2211	  This enables SMBIOS/DMI feature for systems.
2212
2213	  This option is only useful on systems that have UEFI firmware.
2214	  However, even with this option, the resultant kernel should
2215	  continue to boot on existing non-UEFI platforms.
2216
2217endmenu # "Boot options"
2218
2219menu "Power management options"
2220
2221source "kernel/power/Kconfig"
2222
2223config ARCH_HIBERNATION_POSSIBLE
2224	def_bool y
2225	depends on CPU_PM
2226
2227config ARCH_HIBERNATION_HEADER
2228	def_bool y
2229	depends on HIBERNATION
2230
2231config ARCH_SUSPEND_POSSIBLE
2232	def_bool y
2233
2234endmenu # "Power management options"
2235
2236menu "CPU Power Management"
2237
2238source "drivers/cpuidle/Kconfig"
2239
2240source "drivers/cpufreq/Kconfig"
2241
2242endmenu # "CPU Power Management"
2243
2244source "drivers/acpi/Kconfig"
2245
2246source "arch/arm64/kvm/Kconfig"
2247
2248if CRYPTO
2249source "arch/arm64/crypto/Kconfig"
2250endif # CRYPTO
2251