xref: /openbmc/linux/arch/arm64/Kconfig (revision 023e4163)
1config ARM64
2	def_bool y
3	select ACPI_CCA_REQUIRED if ACPI
4	select ACPI_GENERIC_GSI if ACPI
5	select ACPI_GTDT if ACPI
6	select ACPI_IORT if ACPI
7	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
8	select ACPI_MCFG if (ACPI && PCI)
9	select ACPI_SPCR_TABLE if ACPI
10	select ACPI_PPTT if ACPI
11	select ARCH_CLOCKSOURCE_DATA
12	select ARCH_HAS_DEBUG_VIRTUAL
13	select ARCH_HAS_DEVMEM_IS_ALLOWED
14	select ARCH_HAS_DMA_COHERENT_TO_PFN
15	select ARCH_HAS_DMA_MMAP_PGPROT
16	select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
17	select ARCH_HAS_ELF_RANDOMIZE
18	select ARCH_HAS_FAST_MULTIPLIER
19	select ARCH_HAS_FORTIFY_SOURCE
20	select ARCH_HAS_GCOV_PROFILE_ALL
21	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
22	select ARCH_HAS_KCOV
23	select ARCH_HAS_MEMBARRIER_SYNC_CORE
24	select ARCH_HAS_PTE_SPECIAL
25	select ARCH_HAS_SETUP_DMA_OPS
26	select ARCH_HAS_SET_MEMORY
27	select ARCH_HAS_STRICT_KERNEL_RWX
28	select ARCH_HAS_STRICT_MODULE_RWX
29	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
30	select ARCH_HAS_SYNC_DMA_FOR_CPU
31	select ARCH_HAS_SYSCALL_WRAPPER
32	select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
33	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
34	select ARCH_HAVE_NMI_SAFE_CMPXCHG
35	select ARCH_INLINE_READ_LOCK if !PREEMPT
36	select ARCH_INLINE_READ_LOCK_BH if !PREEMPT
37	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPT
38	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPT
39	select ARCH_INLINE_READ_UNLOCK if !PREEMPT
40	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPT
41	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPT
42	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPT
43	select ARCH_INLINE_WRITE_LOCK if !PREEMPT
44	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPT
45	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPT
46	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPT
47	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPT
48	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPT
49	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPT
50	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPT
51	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPT
52	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPT
53	select ARCH_INLINE_SPIN_LOCK if !PREEMPT
54	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPT
55	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPT
56	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPT
57	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPT
58	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPT
59	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPT
60	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPT
61	select ARCH_USE_CMPXCHG_LOCKREF
62	select ARCH_USE_QUEUED_RWLOCKS
63	select ARCH_USE_QUEUED_SPINLOCKS
64	select ARCH_SUPPORTS_MEMORY_FAILURE
65	select ARCH_SUPPORTS_ATOMIC_RMW
66	select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 || CC_IS_CLANG
67	select ARCH_SUPPORTS_NUMA_BALANCING
68	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
69	select ARCH_WANT_FRAME_POINTERS
70	select ARCH_HAS_UBSAN_SANITIZE_ALL
71	select ARM_AMBA
72	select ARM_ARCH_TIMER
73	select ARM_GIC
74	select AUDIT_ARCH_COMPAT_GENERIC
75	select ARM_GIC_V2M if PCI
76	select ARM_GIC_V3
77	select ARM_GIC_V3_ITS if PCI
78	select ARM_PSCI_FW
79	select BUILDTIME_EXTABLE_SORT
80	select CLONE_BACKWARDS
81	select COMMON_CLK
82	select CPU_PM if (SUSPEND || CPU_IDLE)
83	select CRC32
84	select DCACHE_WORD_ACCESS
85	select DMA_DIRECT_REMAP
86	select EDAC_SUPPORT
87	select FRAME_POINTER
88	select GENERIC_ALLOCATOR
89	select GENERIC_ARCH_TOPOLOGY
90	select GENERIC_CLOCKEVENTS
91	select GENERIC_CLOCKEVENTS_BROADCAST
92	select GENERIC_CPU_AUTOPROBE
93	select GENERIC_EARLY_IOREMAP
94	select GENERIC_IDLE_POLL_SETUP
95	select GENERIC_IRQ_MULTI_HANDLER
96	select GENERIC_IRQ_PROBE
97	select GENERIC_IRQ_SHOW
98	select GENERIC_IRQ_SHOW_LEVEL
99	select GENERIC_PCI_IOMAP
100	select GENERIC_SCHED_CLOCK
101	select GENERIC_SMP_IDLE_THREAD
102	select GENERIC_STRNCPY_FROM_USER
103	select GENERIC_STRNLEN_USER
104	select GENERIC_TIME_VSYSCALL
105	select HANDLE_DOMAIN_IRQ
106	select HARDIRQS_SW_RESEND
107	select HAVE_PCI
108	select HAVE_ACPI_APEI if (ACPI && EFI)
109	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
110	select HAVE_ARCH_AUDITSYSCALL
111	select HAVE_ARCH_BITREVERSE
112	select HAVE_ARCH_HUGE_VMAP
113	select HAVE_ARCH_JUMP_LABEL
114	select HAVE_ARCH_JUMP_LABEL_RELATIVE
115	select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
116	select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
117	select HAVE_ARCH_KGDB
118	select HAVE_ARCH_MMAP_RND_BITS
119	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
120	select HAVE_ARCH_PREL32_RELOCATIONS
121	select HAVE_ARCH_SECCOMP_FILTER
122	select HAVE_ARCH_STACKLEAK
123	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
124	select HAVE_ARCH_TRACEHOOK
125	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
126	select HAVE_ARCH_VMAP_STACK
127	select HAVE_ARM_SMCCC
128	select HAVE_EBPF_JIT
129	select HAVE_C_RECORDMCOUNT
130	select HAVE_CMPXCHG_DOUBLE
131	select HAVE_CMPXCHG_LOCAL
132	select HAVE_CONTEXT_TRACKING
133	select HAVE_DEBUG_BUGVERBOSE
134	select HAVE_DEBUG_KMEMLEAK
135	select HAVE_DMA_CONTIGUOUS
136	select HAVE_DYNAMIC_FTRACE
137	select HAVE_EFFICIENT_UNALIGNED_ACCESS
138	select HAVE_FTRACE_MCOUNT_RECORD
139	select HAVE_FUNCTION_TRACER
140	select HAVE_FUNCTION_GRAPH_TRACER
141	select HAVE_GCC_PLUGINS
142	select HAVE_HW_BREAKPOINT if PERF_EVENTS
143	select HAVE_IRQ_TIME_ACCOUNTING
144	select HAVE_MEMBLOCK_NODE_MAP if NUMA
145	select HAVE_NMI
146	select HAVE_PATA_PLATFORM
147	select HAVE_PERF_EVENTS
148	select HAVE_PERF_REGS
149	select HAVE_PERF_USER_STACK_DUMP
150	select HAVE_REGS_AND_STACK_ACCESS_API
151	select HAVE_RCU_TABLE_FREE
152	select HAVE_RCU_TABLE_INVALIDATE
153	select HAVE_RSEQ
154	select HAVE_STACKPROTECTOR
155	select HAVE_SYSCALL_TRACEPOINTS
156	select HAVE_KPROBES
157	select HAVE_KRETPROBES
158	select IOMMU_DMA if IOMMU_SUPPORT
159	select IRQ_DOMAIN
160	select IRQ_FORCED_THREADING
161	select MODULES_USE_ELF_RELA
162	select NEED_DMA_MAP_STATE
163	select NEED_SG_DMA_LENGTH
164	select OF
165	select OF_EARLY_FLATTREE
166	select PCI_DOMAINS_GENERIC if PCI
167	select PCI_ECAM if (ACPI && PCI)
168	select PCI_SYSCALL if PCI
169	select POWER_RESET
170	select POWER_SUPPLY
171	select REFCOUNT_FULL
172	select SPARSE_IRQ
173	select SWIOTLB
174	select SYSCTL_EXCEPTION_TRACE
175	select THREAD_INFO_IN_TASK
176	help
177	  ARM 64-bit (AArch64) Linux support.
178
179config 64BIT
180	def_bool y
181
182config MMU
183	def_bool y
184
185config ARM64_PAGE_SHIFT
186	int
187	default 16 if ARM64_64K_PAGES
188	default 14 if ARM64_16K_PAGES
189	default 12
190
191config ARM64_CONT_SHIFT
192	int
193	default 5 if ARM64_64K_PAGES
194	default 7 if ARM64_16K_PAGES
195	default 4
196
197config ARCH_MMAP_RND_BITS_MIN
198       default 14 if ARM64_64K_PAGES
199       default 16 if ARM64_16K_PAGES
200       default 18
201
202# max bits determined by the following formula:
203#  VA_BITS - PAGE_SHIFT - 3
204config ARCH_MMAP_RND_BITS_MAX
205       default 19 if ARM64_VA_BITS=36
206       default 24 if ARM64_VA_BITS=39
207       default 27 if ARM64_VA_BITS=42
208       default 30 if ARM64_VA_BITS=47
209       default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
210       default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
211       default 33 if ARM64_VA_BITS=48
212       default 14 if ARM64_64K_PAGES
213       default 16 if ARM64_16K_PAGES
214       default 18
215
216config ARCH_MMAP_RND_COMPAT_BITS_MIN
217       default 7 if ARM64_64K_PAGES
218       default 9 if ARM64_16K_PAGES
219       default 11
220
221config ARCH_MMAP_RND_COMPAT_BITS_MAX
222       default 16
223
224config NO_IOPORT_MAP
225	def_bool y if !PCI
226
227config STACKTRACE_SUPPORT
228	def_bool y
229
230config ILLEGAL_POINTER_VALUE
231	hex
232	default 0xdead000000000000
233
234config LOCKDEP_SUPPORT
235	def_bool y
236
237config TRACE_IRQFLAGS_SUPPORT
238	def_bool y
239
240config RWSEM_XCHGADD_ALGORITHM
241	def_bool y
242
243config GENERIC_BUG
244	def_bool y
245	depends on BUG
246
247config GENERIC_BUG_RELATIVE_POINTERS
248	def_bool y
249	depends on GENERIC_BUG
250
251config GENERIC_HWEIGHT
252	def_bool y
253
254config GENERIC_CSUM
255        def_bool y
256
257config GENERIC_CALIBRATE_DELAY
258	def_bool y
259
260config ZONE_DMA32
261	def_bool y
262
263config HAVE_GENERIC_GUP
264	def_bool y
265
266config ARCH_ENABLE_MEMORY_HOTPLUG
267	def_bool y
268
269config SMP
270	def_bool y
271
272config KERNEL_MODE_NEON
273	def_bool y
274
275config FIX_EARLYCON_MEM
276	def_bool y
277
278config PGTABLE_LEVELS
279	int
280	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
281	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
282	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_USER_VA_BITS_52)
283	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
284	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
285	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
286
287config ARCH_SUPPORTS_UPROBES
288	def_bool y
289
290config ARCH_PROC_KCORE_TEXT
291	def_bool y
292
293source "arch/arm64/Kconfig.platforms"
294
295menu "Kernel Features"
296
297menu "ARM errata workarounds via the alternatives framework"
298
299config ARM64_WORKAROUND_CLEAN_CACHE
300	def_bool n
301
302config ARM64_ERRATUM_826319
303	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
304	default y
305	select ARM64_WORKAROUND_CLEAN_CACHE
306	help
307	  This option adds an alternative code sequence to work around ARM
308	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
309	  AXI master interface and an L2 cache.
310
311	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
312	  and is unable to accept a certain write via this interface, it will
313	  not progress on read data presented on the read data channel and the
314	  system can deadlock.
315
316	  The workaround promotes data cache clean instructions to
317	  data cache clean-and-invalidate.
318	  Please note that this does not necessarily enable the workaround,
319	  as it depends on the alternative framework, which will only patch
320	  the kernel if an affected CPU is detected.
321
322	  If unsure, say Y.
323
324config ARM64_ERRATUM_827319
325	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
326	default y
327	select ARM64_WORKAROUND_CLEAN_CACHE
328	help
329	  This option adds an alternative code sequence to work around ARM
330	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
331	  master interface and an L2 cache.
332
333	  Under certain conditions this erratum can cause a clean line eviction
334	  to occur at the same time as another transaction to the same address
335	  on the AMBA 5 CHI interface, which can cause data corruption if the
336	  interconnect reorders the two transactions.
337
338	  The workaround promotes data cache clean instructions to
339	  data cache clean-and-invalidate.
340	  Please note that this does not necessarily enable the workaround,
341	  as it depends on the alternative framework, which will only patch
342	  the kernel if an affected CPU is detected.
343
344	  If unsure, say Y.
345
346config ARM64_ERRATUM_824069
347	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
348	default y
349	select ARM64_WORKAROUND_CLEAN_CACHE
350	help
351	  This option adds an alternative code sequence to work around ARM
352	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
353	  to a coherent interconnect.
354
355	  If a Cortex-A53 processor is executing a store or prefetch for
356	  write instruction at the same time as a processor in another
357	  cluster is executing a cache maintenance operation to the same
358	  address, then this erratum might cause a clean cache line to be
359	  incorrectly marked as dirty.
360
361	  The workaround promotes data cache clean instructions to
362	  data cache clean-and-invalidate.
363	  Please note that this option does not necessarily enable the
364	  workaround, as it depends on the alternative framework, which will
365	  only patch the kernel if an affected CPU is detected.
366
367	  If unsure, say Y.
368
369config ARM64_ERRATUM_819472
370	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
371	default y
372	select ARM64_WORKAROUND_CLEAN_CACHE
373	help
374	  This option adds an alternative code sequence to work around ARM
375	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
376	  present when it is connected to a coherent interconnect.
377
378	  If the processor is executing a load and store exclusive sequence at
379	  the same time as a processor in another cluster is executing a cache
380	  maintenance operation to the same address, then this erratum might
381	  cause data corruption.
382
383	  The workaround promotes data cache clean instructions to
384	  data cache clean-and-invalidate.
385	  Please note that this does not necessarily enable the workaround,
386	  as it depends on the alternative framework, which will only patch
387	  the kernel if an affected CPU is detected.
388
389	  If unsure, say Y.
390
391config ARM64_ERRATUM_832075
392	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
393	default y
394	help
395	  This option adds an alternative code sequence to work around ARM
396	  erratum 832075 on Cortex-A57 parts up to r1p2.
397
398	  Affected Cortex-A57 parts might deadlock when exclusive load/store
399	  instructions to Write-Back memory are mixed with Device loads.
400
401	  The workaround is to promote device loads to use Load-Acquire
402	  semantics.
403	  Please note that this does not necessarily enable the workaround,
404	  as it depends on the alternative framework, which will only patch
405	  the kernel if an affected CPU is detected.
406
407	  If unsure, say Y.
408
409config ARM64_ERRATUM_834220
410	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
411	depends on KVM
412	default y
413	help
414	  This option adds an alternative code sequence to work around ARM
415	  erratum 834220 on Cortex-A57 parts up to r1p2.
416
417	  Affected Cortex-A57 parts might report a Stage 2 translation
418	  fault as the result of a Stage 1 fault for load crossing a
419	  page boundary when there is a permission or device memory
420	  alignment fault at Stage 1 and a translation fault at Stage 2.
421
422	  The workaround is to verify that the Stage 1 translation
423	  doesn't generate a fault before handling the Stage 2 fault.
424	  Please note that this does not necessarily enable the workaround,
425	  as it depends on the alternative framework, which will only patch
426	  the kernel if an affected CPU is detected.
427
428	  If unsure, say Y.
429
430config ARM64_ERRATUM_845719
431	bool "Cortex-A53: 845719: a load might read incorrect data"
432	depends on COMPAT
433	default y
434	help
435	  This option adds an alternative code sequence to work around ARM
436	  erratum 845719 on Cortex-A53 parts up to r0p4.
437
438	  When running a compat (AArch32) userspace on an affected Cortex-A53
439	  part, a load at EL0 from a virtual address that matches the bottom 32
440	  bits of the virtual address used by a recent load at (AArch64) EL1
441	  might return incorrect data.
442
443	  The workaround is to write the contextidr_el1 register on exception
444	  return to a 32-bit task.
445	  Please note that this does not necessarily enable the workaround,
446	  as it depends on the alternative framework, which will only patch
447	  the kernel if an affected CPU is detected.
448
449	  If unsure, say Y.
450
451config ARM64_ERRATUM_843419
452	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
453	default y
454	select ARM64_MODULE_PLTS if MODULES
455	help
456	  This option links the kernel with '--fix-cortex-a53-843419' and
457	  enables PLT support to replace certain ADRP instructions, which can
458	  cause subsequent memory accesses to use an incorrect address on
459	  Cortex-A53 parts up to r0p4.
460
461	  If unsure, say Y.
462
463config ARM64_ERRATUM_1024718
464	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
465	default y
466	help
467	  This option adds work around for Arm Cortex-A55 Erratum 1024718.
468
469	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
470	  update of the hardware dirty bit when the DBM/AP bits are updated
471	  without a break-before-make. The work around is to disable the usage
472	  of hardware DBM locally on the affected cores. CPUs not affected by
473	  erratum will continue to use the feature.
474
475	  If unsure, say Y.
476
477config ARM64_ERRATUM_1188873
478	bool "Cortex-A76: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
479	default y
480	select ARM_ARCH_TIMER_OOL_WORKAROUND
481	help
482	  This option adds work arounds for ARM Cortex-A76 erratum 1188873
483
484	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could cause
485	  register corruption when accessing the timer registers from
486	  AArch32 userspace.
487
488	  If unsure, say Y.
489
490config ARM64_ERRATUM_1165522
491	bool "Cortex-A76: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
492	default y
493	help
494	  This option adds work arounds for ARM Cortex-A76 erratum 1165522
495
496	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
497	  corrupted TLBs by speculating an AT instruction during a guest
498	  context switch.
499
500	  If unsure, say Y.
501
502config ARM64_ERRATUM_1286807
503	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
504	default y
505	select ARM64_WORKAROUND_REPEAT_TLBI
506	help
507	  This option adds workaround for ARM Cortex-A76 erratum 1286807
508
509	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
510	  address for a cacheable mapping of a location is being
511	  accessed by a core while another core is remapping the virtual
512	  address to a new physical page using the recommended
513	  break-before-make sequence, then under very rare circumstances
514	  TLBI+DSB completes before a read using the translation being
515	  invalidated has been observed by other observers. The
516	  workaround repeats the TLBI+DSB operation.
517
518	  If unsure, say Y.
519
520config CAVIUM_ERRATUM_22375
521	bool "Cavium erratum 22375, 24313"
522	default y
523	help
524	  Enable workaround for erratum 22375, 24313.
525
526	  This implements two gicv3-its errata workarounds for ThunderX. Both
527	  with small impact affecting only ITS table allocation.
528
529	    erratum 22375: only alloc 8MB table size
530	    erratum 24313: ignore memory access type
531
532	  The fixes are in ITS initialization and basically ignore memory access
533	  type and table size provided by the TYPER and BASER registers.
534
535	  If unsure, say Y.
536
537config CAVIUM_ERRATUM_23144
538	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
539	depends on NUMA
540	default y
541	help
542	  ITS SYNC command hang for cross node io and collections/cpu mapping.
543
544	  If unsure, say Y.
545
546config CAVIUM_ERRATUM_23154
547	bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
548	default y
549	help
550	  The gicv3 of ThunderX requires a modified version for
551	  reading the IAR status to ensure data synchronization
552	  (access to icc_iar1_el1 is not sync'ed before and after).
553
554	  If unsure, say Y.
555
556config CAVIUM_ERRATUM_27456
557	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
558	default y
559	help
560	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
561	  instructions may cause the icache to become corrupted if it
562	  contains data for a non-current ASID.  The fix is to
563	  invalidate the icache when changing the mm context.
564
565	  If unsure, say Y.
566
567config CAVIUM_ERRATUM_30115
568	bool "Cavium erratum 30115: Guest may disable interrupts in host"
569	default y
570	help
571	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
572	  1.2, and T83 Pass 1.0, KVM guest execution may disable
573	  interrupts in host. Trapping both GICv3 group-0 and group-1
574	  accesses sidesteps the issue.
575
576	  If unsure, say Y.
577
578config QCOM_FALKOR_ERRATUM_1003
579	bool "Falkor E1003: Incorrect translation due to ASID change"
580	default y
581	help
582	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
583	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
584	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
585	  then only for entries in the walk cache, since the leaf translation
586	  is unchanged. Work around the erratum by invalidating the walk cache
587	  entries for the trampoline before entering the kernel proper.
588
589config ARM64_WORKAROUND_REPEAT_TLBI
590	bool
591	help
592	  Enable the repeat TLBI workaround for Falkor erratum 1009 and
593	  Cortex-A76 erratum 1286807.
594
595config QCOM_FALKOR_ERRATUM_1009
596	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
597	default y
598	select ARM64_WORKAROUND_REPEAT_TLBI
599	help
600	  On Falkor v1, the CPU may prematurely complete a DSB following a
601	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
602	  one more time to fix the issue.
603
604	  If unsure, say Y.
605
606config QCOM_QDF2400_ERRATUM_0065
607	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
608	default y
609	help
610	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
611	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
612	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
613
614	  If unsure, say Y.
615
616config SOCIONEXT_SYNQUACER_PREITS
617	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
618	default y
619	help
620	  Socionext Synquacer SoCs implement a separate h/w block to generate
621	  MSI doorbell writes with non-zero values for the device ID.
622
623	  If unsure, say Y.
624
625config HISILICON_ERRATUM_161600802
626	bool "Hip07 161600802: Erroneous redistributor VLPI base"
627	default y
628	help
629	  The HiSilicon Hip07 SoC usees the wrong redistributor base
630	  when issued ITS commands such as VMOVP and VMAPP, and requires
631	  a 128kB offset to be applied to the target address in this commands.
632
633	  If unsure, say Y.
634
635config QCOM_FALKOR_ERRATUM_E1041
636	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
637	default y
638	help
639	  Falkor CPU may speculatively fetch instructions from an improper
640	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
641	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
642
643	  If unsure, say Y.
644
645config FUJITSU_ERRATUM_010001
646	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
647	default y
648	help
649	  This option adds workaround for Fujitsu-A64FX erratum E#010001.
650	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
651	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
652	  This fault occurs under a specific hardware condition when a
653	  load/store instruction performs an address translation using:
654	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
655	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
656	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
657	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
658
659	  The workaround is to ensure these bits are clear in TCR_ELx.
660	  The workaround only affect the Fujitsu-A64FX.
661
662	  If unsure, say Y.
663
664endmenu
665
666
667choice
668	prompt "Page size"
669	default ARM64_4K_PAGES
670	help
671	  Page size (translation granule) configuration.
672
673config ARM64_4K_PAGES
674	bool "4KB"
675	help
676	  This feature enables 4KB pages support.
677
678config ARM64_16K_PAGES
679	bool "16KB"
680	help
681	  The system will use 16KB pages support. AArch32 emulation
682	  requires applications compiled with 16K (or a multiple of 16K)
683	  aligned segments.
684
685config ARM64_64K_PAGES
686	bool "64KB"
687	help
688	  This feature enables 64KB pages support (4KB by default)
689	  allowing only two levels of page tables and faster TLB
690	  look-up. AArch32 emulation requires applications compiled
691	  with 64K aligned segments.
692
693endchoice
694
695choice
696	prompt "Virtual address space size"
697	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
698	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
699	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
700	help
701	  Allows choosing one of multiple possible virtual address
702	  space sizes. The level of translation table is determined by
703	  a combination of page size and virtual address space size.
704
705config ARM64_VA_BITS_36
706	bool "36-bit" if EXPERT
707	depends on ARM64_16K_PAGES
708
709config ARM64_VA_BITS_39
710	bool "39-bit"
711	depends on ARM64_4K_PAGES
712
713config ARM64_VA_BITS_42
714	bool "42-bit"
715	depends on ARM64_64K_PAGES
716
717config ARM64_VA_BITS_47
718	bool "47-bit"
719	depends on ARM64_16K_PAGES
720
721config ARM64_VA_BITS_48
722	bool "48-bit"
723
724config ARM64_USER_VA_BITS_52
725	bool "52-bit (user)"
726	depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
727	help
728	  Enable 52-bit virtual addressing for userspace when explicitly
729	  requested via a hint to mmap(). The kernel will continue to
730	  use 48-bit virtual addresses for its own mappings.
731
732	  NOTE: Enabling 52-bit virtual addressing in conjunction with
733	  ARMv8.3 Pointer Authentication will result in the PAC being
734	  reduced from 7 bits to 3 bits, which may have a significant
735	  impact on its susceptibility to brute-force attacks.
736
737	  If unsure, select 48-bit virtual addressing instead.
738
739endchoice
740
741config ARM64_FORCE_52BIT
742	bool "Force 52-bit virtual addresses for userspace"
743	depends on ARM64_USER_VA_BITS_52 && EXPERT
744	help
745	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
746	  to maintain compatibility with older software by providing 48-bit VAs
747	  unless a hint is supplied to mmap.
748
749	  This configuration option disables the 48-bit compatibility logic, and
750	  forces all userspace addresses to be 52-bit on HW that supports it. One
751	  should only enable this configuration option for stress testing userspace
752	  memory management code. If unsure say N here.
753
754config ARM64_VA_BITS
755	int
756	default 36 if ARM64_VA_BITS_36
757	default 39 if ARM64_VA_BITS_39
758	default 42 if ARM64_VA_BITS_42
759	default 47 if ARM64_VA_BITS_47
760	default 48 if ARM64_VA_BITS_48 || ARM64_USER_VA_BITS_52
761
762choice
763	prompt "Physical address space size"
764	default ARM64_PA_BITS_48
765	help
766	  Choose the maximum physical address range that the kernel will
767	  support.
768
769config ARM64_PA_BITS_48
770	bool "48-bit"
771
772config ARM64_PA_BITS_52
773	bool "52-bit (ARMv8.2)"
774	depends on ARM64_64K_PAGES
775	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
776	help
777	  Enable support for a 52-bit physical address space, introduced as
778	  part of the ARMv8.2-LPA extension.
779
780	  With this enabled, the kernel will also continue to work on CPUs that
781	  do not support ARMv8.2-LPA, but with some added memory overhead (and
782	  minor performance overhead).
783
784endchoice
785
786config ARM64_PA_BITS
787	int
788	default 48 if ARM64_PA_BITS_48
789	default 52 if ARM64_PA_BITS_52
790
791config CPU_BIG_ENDIAN
792       bool "Build big-endian kernel"
793       help
794         Say Y if you plan on running a kernel in big-endian mode.
795
796config SCHED_MC
797	bool "Multi-core scheduler support"
798	help
799	  Multi-core scheduler support improves the CPU scheduler's decision
800	  making when dealing with multi-core CPU chips at a cost of slightly
801	  increased overhead in some places. If unsure say N here.
802
803config SCHED_SMT
804	bool "SMT scheduler support"
805	help
806	  Improves the CPU scheduler's decision making when dealing with
807	  MultiThreading at a cost of slightly increased overhead in some
808	  places. If unsure say N here.
809
810config NR_CPUS
811	int "Maximum number of CPUs (2-4096)"
812	range 2 4096
813	default "256"
814
815config HOTPLUG_CPU
816	bool "Support for hot-pluggable CPUs"
817	select GENERIC_IRQ_MIGRATION
818	help
819	  Say Y here to experiment with turning CPUs off and on.  CPUs
820	  can be controlled through /sys/devices/system/cpu.
821
822# Common NUMA Features
823config NUMA
824	bool "Numa Memory Allocation and Scheduler Support"
825	select ACPI_NUMA if ACPI
826	select OF_NUMA
827	help
828	  Enable NUMA (Non Uniform Memory Access) support.
829
830	  The kernel will try to allocate memory used by a CPU on the
831	  local memory of the CPU and add some more
832	  NUMA awareness to the kernel.
833
834config NODES_SHIFT
835	int "Maximum NUMA Nodes (as a power of 2)"
836	range 1 10
837	default "2"
838	depends on NEED_MULTIPLE_NODES
839	help
840	  Specify the maximum number of NUMA Nodes available on the target
841	  system.  Increases memory reserved to accommodate various tables.
842
843config USE_PERCPU_NUMA_NODE_ID
844	def_bool y
845	depends on NUMA
846
847config HAVE_SETUP_PER_CPU_AREA
848	def_bool y
849	depends on NUMA
850
851config NEED_PER_CPU_EMBED_FIRST_CHUNK
852	def_bool y
853	depends on NUMA
854
855config HOLES_IN_ZONE
856	def_bool y
857
858source "kernel/Kconfig.hz"
859
860config ARCH_SUPPORTS_DEBUG_PAGEALLOC
861	def_bool y
862
863config ARCH_SPARSEMEM_ENABLE
864	def_bool y
865	select SPARSEMEM_VMEMMAP_ENABLE
866
867config ARCH_SPARSEMEM_DEFAULT
868	def_bool ARCH_SPARSEMEM_ENABLE
869
870config ARCH_SELECT_MEMORY_MODEL
871	def_bool ARCH_SPARSEMEM_ENABLE
872
873config ARCH_FLATMEM_ENABLE
874	def_bool !NUMA
875
876config HAVE_ARCH_PFN_VALID
877	def_bool y
878
879config HW_PERF_EVENTS
880	def_bool y
881	depends on ARM_PMU
882
883config SYS_SUPPORTS_HUGETLBFS
884	def_bool y
885
886config ARCH_WANT_HUGE_PMD_SHARE
887	def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
888
889config ARCH_HAS_CACHE_LINE_SIZE
890	def_bool y
891
892config SECCOMP
893	bool "Enable seccomp to safely compute untrusted bytecode"
894	---help---
895	  This kernel feature is useful for number crunching applications
896	  that may need to compute untrusted bytecode during their
897	  execution. By using pipes or other transports made available to
898	  the process as file descriptors supporting the read/write
899	  syscalls, it's possible to isolate those applications in
900	  their own address space using seccomp. Once seccomp is
901	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
902	  and the task is only allowed to execute a few safe syscalls
903	  defined by each seccomp mode.
904
905config PARAVIRT
906	bool "Enable paravirtualization code"
907	help
908	  This changes the kernel so it can modify itself when it is run
909	  under a hypervisor, potentially improving performance significantly
910	  over full virtualization.
911
912config PARAVIRT_TIME_ACCOUNTING
913	bool "Paravirtual steal time accounting"
914	select PARAVIRT
915	default n
916	help
917	  Select this option to enable fine granularity task steal time
918	  accounting. Time spent executing other tasks in parallel with
919	  the current vCPU is discounted from the vCPU power. To account for
920	  that, there can be a small performance impact.
921
922	  If in doubt, say N here.
923
924config KEXEC
925	depends on PM_SLEEP_SMP
926	select KEXEC_CORE
927	bool "kexec system call"
928	---help---
929	  kexec is a system call that implements the ability to shutdown your
930	  current kernel, and to start another kernel.  It is like a reboot
931	  but it is independent of the system firmware.   And like a reboot
932	  you can start any kernel with it, not just Linux.
933
934config KEXEC_FILE
935	bool "kexec file based system call"
936	select KEXEC_CORE
937	help
938	  This is new version of kexec system call. This system call is
939	  file based and takes file descriptors as system call argument
940	  for kernel and initramfs as opposed to list of segments as
941	  accepted by previous system call.
942
943config KEXEC_VERIFY_SIG
944	bool "Verify kernel signature during kexec_file_load() syscall"
945	depends on KEXEC_FILE
946	help
947	  Select this option to verify a signature with loaded kernel
948	  image. If configured, any attempt of loading a image without
949	  valid signature will fail.
950
951	  In addition to that option, you need to enable signature
952	  verification for the corresponding kernel image type being
953	  loaded in order for this to work.
954
955config KEXEC_IMAGE_VERIFY_SIG
956	bool "Enable Image signature verification support"
957	default y
958	depends on KEXEC_VERIFY_SIG
959	depends on EFI && SIGNED_PE_FILE_VERIFICATION
960	help
961	  Enable Image signature verification support.
962
963comment "Support for PE file signature verification disabled"
964	depends on KEXEC_VERIFY_SIG
965	depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
966
967config CRASH_DUMP
968	bool "Build kdump crash kernel"
969	help
970	  Generate crash dump after being started by kexec. This should
971	  be normally only set in special crash dump kernels which are
972	  loaded in the main kernel with kexec-tools into a specially
973	  reserved region and then later executed after a crash by
974	  kdump/kexec.
975
976	  For more details see Documentation/kdump/kdump.txt
977
978config XEN_DOM0
979	def_bool y
980	depends on XEN
981
982config XEN
983	bool "Xen guest support on ARM64"
984	depends on ARM64 && OF
985	select SWIOTLB_XEN
986	select PARAVIRT
987	help
988	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
989
990config FORCE_MAX_ZONEORDER
991	int
992	default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
993	default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
994	default "11"
995	help
996	  The kernel memory allocator divides physically contiguous memory
997	  blocks into "zones", where each zone is a power of two number of
998	  pages.  This option selects the largest power of two that the kernel
999	  keeps in the memory allocator.  If you need to allocate very large
1000	  blocks of physically contiguous memory, then you may need to
1001	  increase this value.
1002
1003	  This config option is actually maximum order plus one. For example,
1004	  a value of 11 means that the largest free memory block is 2^10 pages.
1005
1006	  We make sure that we can allocate upto a HugePage size for each configuration.
1007	  Hence we have :
1008		MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
1009
1010	  However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
1011	  4M allocations matching the default size used by generic code.
1012
1013config UNMAP_KERNEL_AT_EL0
1014	bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
1015	default y
1016	help
1017	  Speculation attacks against some high-performance processors can
1018	  be used to bypass MMU permission checks and leak kernel data to
1019	  userspace. This can be defended against by unmapping the kernel
1020	  when running in userspace, mapping it back in on exception entry
1021	  via a trampoline page in the vector table.
1022
1023	  If unsure, say Y.
1024
1025config HARDEN_BRANCH_PREDICTOR
1026	bool "Harden the branch predictor against aliasing attacks" if EXPERT
1027	default y
1028	help
1029	  Speculation attacks against some high-performance processors rely on
1030	  being able to manipulate the branch predictor for a victim context by
1031	  executing aliasing branches in the attacker context.  Such attacks
1032	  can be partially mitigated against by clearing internal branch
1033	  predictor state and limiting the prediction logic in some situations.
1034
1035	  This config option will take CPU-specific actions to harden the
1036	  branch predictor against aliasing attacks and may rely on specific
1037	  instruction sequences or control bits being set by the system
1038	  firmware.
1039
1040	  If unsure, say Y.
1041
1042config HARDEN_EL2_VECTORS
1043	bool "Harden EL2 vector mapping against system register leak" if EXPERT
1044	default y
1045	help
1046	  Speculation attacks against some high-performance processors can
1047	  be used to leak privileged information such as the vector base
1048	  register, resulting in a potential defeat of the EL2 layout
1049	  randomization.
1050
1051	  This config option will map the vectors to a fixed location,
1052	  independent of the EL2 code mapping, so that revealing VBAR_EL2
1053	  to an attacker does not give away any extra information. This
1054	  only gets enabled on affected CPUs.
1055
1056	  If unsure, say Y.
1057
1058config ARM64_SSBD
1059	bool "Speculative Store Bypass Disable" if EXPERT
1060	default y
1061	help
1062	  This enables mitigation of the bypassing of previous stores
1063	  by speculative loads.
1064
1065	  If unsure, say Y.
1066
1067config RODATA_FULL_DEFAULT_ENABLED
1068	bool "Apply r/o permissions of VM areas also to their linear aliases"
1069	default y
1070	help
1071	  Apply read-only attributes of VM areas to the linear alias of
1072	  the backing pages as well. This prevents code or read-only data
1073	  from being modified (inadvertently or intentionally) via another
1074	  mapping of the same memory page. This additional enhancement can
1075	  be turned off at runtime by passing rodata=[off|on] (and turned on
1076	  with rodata=full if this option is set to 'n')
1077
1078	  This requires the linear region to be mapped down to pages,
1079	  which may adversely affect performance in some cases.
1080
1081menuconfig ARMV8_DEPRECATED
1082	bool "Emulate deprecated/obsolete ARMv8 instructions"
1083	depends on COMPAT
1084	depends on SYSCTL
1085	help
1086	  Legacy software support may require certain instructions
1087	  that have been deprecated or obsoleted in the architecture.
1088
1089	  Enable this config to enable selective emulation of these
1090	  features.
1091
1092	  If unsure, say Y
1093
1094if ARMV8_DEPRECATED
1095
1096config SWP_EMULATION
1097	bool "Emulate SWP/SWPB instructions"
1098	help
1099	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1100	  they are always undefined. Say Y here to enable software
1101	  emulation of these instructions for userspace using LDXR/STXR.
1102
1103	  In some older versions of glibc [<=2.8] SWP is used during futex
1104	  trylock() operations with the assumption that the code will not
1105	  be preempted. This invalid assumption may be more likely to fail
1106	  with SWP emulation enabled, leading to deadlock of the user
1107	  application.
1108
1109	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1110	  on an external transaction monitoring block called a global
1111	  monitor to maintain update atomicity. If your system does not
1112	  implement a global monitor, this option can cause programs that
1113	  perform SWP operations to uncached memory to deadlock.
1114
1115	  If unsure, say Y
1116
1117config CP15_BARRIER_EMULATION
1118	bool "Emulate CP15 Barrier instructions"
1119	help
1120	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1121	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1122	  strongly recommended to use the ISB, DSB, and DMB
1123	  instructions instead.
1124
1125	  Say Y here to enable software emulation of these
1126	  instructions for AArch32 userspace code. When this option is
1127	  enabled, CP15 barrier usage is traced which can help
1128	  identify software that needs updating.
1129
1130	  If unsure, say Y
1131
1132config SETEND_EMULATION
1133	bool "Emulate SETEND instruction"
1134	help
1135	  The SETEND instruction alters the data-endianness of the
1136	  AArch32 EL0, and is deprecated in ARMv8.
1137
1138	  Say Y here to enable software emulation of the instruction
1139	  for AArch32 userspace code.
1140
1141	  Note: All the cpus on the system must have mixed endian support at EL0
1142	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1143	  endian - is hotplugged in after this feature has been enabled, there could
1144	  be unexpected results in the applications.
1145
1146	  If unsure, say Y
1147endif
1148
1149config ARM64_SW_TTBR0_PAN
1150	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1151	help
1152	  Enabling this option prevents the kernel from accessing
1153	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1154	  zeroed area and reserved ASID. The user access routines
1155	  restore the valid TTBR0_EL1 temporarily.
1156
1157menu "ARMv8.1 architectural features"
1158
1159config ARM64_HW_AFDBM
1160	bool "Support for hardware updates of the Access and Dirty page flags"
1161	default y
1162	help
1163	  The ARMv8.1 architecture extensions introduce support for
1164	  hardware updates of the access and dirty information in page
1165	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1166	  capable processors, accesses to pages with PTE_AF cleared will
1167	  set this bit instead of raising an access flag fault.
1168	  Similarly, writes to read-only pages with the DBM bit set will
1169	  clear the read-only bit (AP[2]) instead of raising a
1170	  permission fault.
1171
1172	  Kernels built with this configuration option enabled continue
1173	  to work on pre-ARMv8.1 hardware and the performance impact is
1174	  minimal. If unsure, say Y.
1175
1176config ARM64_PAN
1177	bool "Enable support for Privileged Access Never (PAN)"
1178	default y
1179	help
1180	 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1181	 prevents the kernel or hypervisor from accessing user-space (EL0)
1182	 memory directly.
1183
1184	 Choosing this option will cause any unprotected (not using
1185	 copy_to_user et al) memory access to fail with a permission fault.
1186
1187	 The feature is detected at runtime, and will remain as a 'nop'
1188	 instruction if the cpu does not implement the feature.
1189
1190config ARM64_LSE_ATOMICS
1191	bool "Atomic instructions"
1192	default y
1193	help
1194	  As part of the Large System Extensions, ARMv8.1 introduces new
1195	  atomic instructions that are designed specifically to scale in
1196	  very large systems.
1197
1198	  Say Y here to make use of these instructions for the in-kernel
1199	  atomic routines. This incurs a small overhead on CPUs that do
1200	  not support these instructions and requires the kernel to be
1201	  built with binutils >= 2.25 in order for the new instructions
1202	  to be used.
1203
1204config ARM64_VHE
1205	bool "Enable support for Virtualization Host Extensions (VHE)"
1206	default y
1207	help
1208	  Virtualization Host Extensions (VHE) allow the kernel to run
1209	  directly at EL2 (instead of EL1) on processors that support
1210	  it. This leads to better performance for KVM, as they reduce
1211	  the cost of the world switch.
1212
1213	  Selecting this option allows the VHE feature to be detected
1214	  at runtime, and does not affect processors that do not
1215	  implement this feature.
1216
1217endmenu
1218
1219menu "ARMv8.2 architectural features"
1220
1221config ARM64_UAO
1222	bool "Enable support for User Access Override (UAO)"
1223	default y
1224	help
1225	  User Access Override (UAO; part of the ARMv8.2 Extensions)
1226	  causes the 'unprivileged' variant of the load/store instructions to
1227	  be overridden to be privileged.
1228
1229	  This option changes get_user() and friends to use the 'unprivileged'
1230	  variant of the load/store instructions. This ensures that user-space
1231	  really did have access to the supplied memory. When addr_limit is
1232	  set to kernel memory the UAO bit will be set, allowing privileged
1233	  access to kernel memory.
1234
1235	  Choosing this option will cause copy_to_user() et al to use user-space
1236	  memory permissions.
1237
1238	  The feature is detected at runtime, the kernel will use the
1239	  regular load/store instructions if the cpu does not implement the
1240	  feature.
1241
1242config ARM64_PMEM
1243	bool "Enable support for persistent memory"
1244	select ARCH_HAS_PMEM_API
1245	select ARCH_HAS_UACCESS_FLUSHCACHE
1246	help
1247	  Say Y to enable support for the persistent memory API based on the
1248	  ARMv8.2 DCPoP feature.
1249
1250	  The feature is detected at runtime, and the kernel will use DC CVAC
1251	  operations if DC CVAP is not supported (following the behaviour of
1252	  DC CVAP itself if the system does not define a point of persistence).
1253
1254config ARM64_RAS_EXTN
1255	bool "Enable support for RAS CPU Extensions"
1256	default y
1257	help
1258	  CPUs that support the Reliability, Availability and Serviceability
1259	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1260	  errors, classify them and report them to software.
1261
1262	  On CPUs with these extensions system software can use additional
1263	  barriers to determine if faults are pending and read the
1264	  classification from a new set of registers.
1265
1266	  Selecting this feature will allow the kernel to use these barriers
1267	  and access the new registers if the system supports the extension.
1268	  Platform RAS features may additionally depend on firmware support.
1269
1270config ARM64_CNP
1271	bool "Enable support for Common Not Private (CNP) translations"
1272	default y
1273	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1274	help
1275	  Common Not Private (CNP) allows translation table entries to
1276	  be shared between different PEs in the same inner shareable
1277	  domain, so the hardware can use this fact to optimise the
1278	  caching of such entries in the TLB.
1279
1280	  Selecting this option allows the CNP feature to be detected
1281	  at runtime, and does not affect PEs that do not implement
1282	  this feature.
1283
1284endmenu
1285
1286menu "ARMv8.3 architectural features"
1287
1288config ARM64_PTR_AUTH
1289	bool "Enable support for pointer authentication"
1290	default y
1291	help
1292	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1293	  instructions for signing and authenticating pointers against secret
1294	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1295	  and other attacks.
1296
1297	  This option enables these instructions at EL0 (i.e. for userspace).
1298
1299	  Choosing this option will cause the kernel to initialise secret keys
1300	  for each process at exec() time, with these keys being
1301	  context-switched along with the process.
1302
1303	  The feature is detected at runtime. If the feature is not present in
1304	  hardware it will not be advertised to userspace nor will it be
1305	  enabled.
1306
1307endmenu
1308
1309config ARM64_SVE
1310	bool "ARM Scalable Vector Extension support"
1311	default y
1312	depends on !KVM || ARM64_VHE
1313	help
1314	  The Scalable Vector Extension (SVE) is an extension to the AArch64
1315	  execution state which complements and extends the SIMD functionality
1316	  of the base architecture to support much larger vectors and to enable
1317	  additional vectorisation opportunities.
1318
1319	  To enable use of this extension on CPUs that implement it, say Y.
1320
1321	  Note that for architectural reasons, firmware _must_ implement SVE
1322	  support when running on SVE capable hardware.  The required support
1323	  is present in:
1324
1325	    * version 1.5 and later of the ARM Trusted Firmware
1326	    * the AArch64 boot wrapper since commit 5e1261e08abf
1327	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
1328
1329	  For other firmware implementations, consult the firmware documentation
1330	  or vendor.
1331
1332	  If you need the kernel to boot on SVE-capable hardware with broken
1333	  firmware, you may need to say N here until you get your firmware
1334	  fixed.  Otherwise, you may experience firmware panics or lockups when
1335	  booting the kernel.  If unsure and you are not observing these
1336	  symptoms, you should assume that it is safe to say Y.
1337
1338	  CPUs that support SVE are architecturally required to support the
1339	  Virtualization Host Extensions (VHE), so the kernel makes no
1340	  provision for supporting SVE alongside KVM without VHE enabled.
1341	  Thus, you will need to enable CONFIG_ARM64_VHE if you want to support
1342	  KVM in the same kernel image.
1343
1344config ARM64_MODULE_PLTS
1345	bool
1346	select HAVE_MOD_ARCH_SPECIFIC
1347
1348config ARM64_PSEUDO_NMI
1349	bool "Support for NMI-like interrupts"
1350	select CONFIG_ARM_GIC_V3
1351	help
1352	  Adds support for mimicking Non-Maskable Interrupts through the use of
1353	  GIC interrupt priority. This support requires version 3 or later of
1354	  Arm GIC.
1355
1356	  This high priority configuration for interrupts needs to be
1357	  explicitly enabled by setting the kernel parameter
1358	  "irqchip.gicv3_pseudo_nmi" to 1.
1359
1360	  If unsure, say N
1361
1362config RELOCATABLE
1363	bool
1364	help
1365	  This builds the kernel as a Position Independent Executable (PIE),
1366	  which retains all relocation metadata required to relocate the
1367	  kernel binary at runtime to a different virtual address than the
1368	  address it was linked at.
1369	  Since AArch64 uses the RELA relocation format, this requires a
1370	  relocation pass at runtime even if the kernel is loaded at the
1371	  same address it was linked at.
1372
1373config RANDOMIZE_BASE
1374	bool "Randomize the address of the kernel image"
1375	select ARM64_MODULE_PLTS if MODULES
1376	select RELOCATABLE
1377	help
1378	  Randomizes the virtual address at which the kernel image is
1379	  loaded, as a security feature that deters exploit attempts
1380	  relying on knowledge of the location of kernel internals.
1381
1382	  It is the bootloader's job to provide entropy, by passing a
1383	  random u64 value in /chosen/kaslr-seed at kernel entry.
1384
1385	  When booting via the UEFI stub, it will invoke the firmware's
1386	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1387	  to the kernel proper. In addition, it will randomise the physical
1388	  location of the kernel Image as well.
1389
1390	  If unsure, say N.
1391
1392config RANDOMIZE_MODULE_REGION_FULL
1393	bool "Randomize the module region over a 4 GB range"
1394	depends on RANDOMIZE_BASE
1395	default y
1396	help
1397	  Randomizes the location of the module region inside a 4 GB window
1398	  covering the core kernel. This way, it is less likely for modules
1399	  to leak information about the location of core kernel data structures
1400	  but it does imply that function calls between modules and the core
1401	  kernel will need to be resolved via veneers in the module PLT.
1402
1403	  When this option is not set, the module region will be randomized over
1404	  a limited range that contains the [_stext, _etext] interval of the
1405	  core kernel, so branch relocations are always in range.
1406
1407config CC_HAVE_STACKPROTECTOR_SYSREG
1408	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
1409
1410config STACKPROTECTOR_PER_TASK
1411	def_bool y
1412	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
1413
1414endmenu
1415
1416menu "Boot options"
1417
1418config ARM64_ACPI_PARKING_PROTOCOL
1419	bool "Enable support for the ARM64 ACPI parking protocol"
1420	depends on ACPI
1421	help
1422	  Enable support for the ARM64 ACPI parking protocol. If disabled
1423	  the kernel will not allow booting through the ARM64 ACPI parking
1424	  protocol even if the corresponding data is present in the ACPI
1425	  MADT table.
1426
1427config CMDLINE
1428	string "Default kernel command string"
1429	default ""
1430	help
1431	  Provide a set of default command-line options at build time by
1432	  entering them here. As a minimum, you should specify the the
1433	  root device (e.g. root=/dev/nfs).
1434
1435config CMDLINE_FORCE
1436	bool "Always use the default kernel command string"
1437	help
1438	  Always use the default kernel command string, even if the boot
1439	  loader passes other arguments to the kernel.
1440	  This is useful if you cannot or don't want to change the
1441	  command-line options your boot loader passes to the kernel.
1442
1443config EFI_STUB
1444	bool
1445
1446config EFI
1447	bool "UEFI runtime support"
1448	depends on OF && !CPU_BIG_ENDIAN
1449	depends on KERNEL_MODE_NEON
1450	select ARCH_SUPPORTS_ACPI
1451	select LIBFDT
1452	select UCS2_STRING
1453	select EFI_PARAMS_FROM_FDT
1454	select EFI_RUNTIME_WRAPPERS
1455	select EFI_STUB
1456	select EFI_ARMSTUB
1457	default y
1458	help
1459	  This option provides support for runtime services provided
1460	  by UEFI firmware (such as non-volatile variables, realtime
1461          clock, and platform reset). A UEFI stub is also provided to
1462	  allow the kernel to be booted as an EFI application. This
1463	  is only useful on systems that have UEFI firmware.
1464
1465config DMI
1466	bool "Enable support for SMBIOS (DMI) tables"
1467	depends on EFI
1468	default y
1469	help
1470	  This enables SMBIOS/DMI feature for systems.
1471
1472	  This option is only useful on systems that have UEFI firmware.
1473	  However, even with this option, the resultant kernel should
1474	  continue to boot on existing non-UEFI platforms.
1475
1476endmenu
1477
1478config COMPAT
1479	bool "Kernel support for 32-bit EL0"
1480	depends on ARM64_4K_PAGES || EXPERT
1481	select COMPAT_BINFMT_ELF if BINFMT_ELF
1482	select HAVE_UID16
1483	select OLD_SIGSUSPEND3
1484	select COMPAT_OLD_SIGACTION
1485	help
1486	  This option enables support for a 32-bit EL0 running under a 64-bit
1487	  kernel at EL1. AArch32-specific components such as system calls,
1488	  the user helper functions, VFP support and the ptrace interface are
1489	  handled appropriately by the kernel.
1490
1491	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1492	  that you will only be able to execute AArch32 binaries that were compiled
1493	  with page size aligned segments.
1494
1495	  If you want to execute 32-bit userspace applications, say Y.
1496
1497config SYSVIPC_COMPAT
1498	def_bool y
1499	depends on COMPAT && SYSVIPC
1500
1501config ARCH_ENABLE_HUGEPAGE_MIGRATION
1502	def_bool y
1503	depends on HUGETLB_PAGE && MIGRATION
1504
1505menu "Power management options"
1506
1507source "kernel/power/Kconfig"
1508
1509config ARCH_HIBERNATION_POSSIBLE
1510	def_bool y
1511	depends on CPU_PM
1512
1513config ARCH_HIBERNATION_HEADER
1514	def_bool y
1515	depends on HIBERNATION
1516
1517config ARCH_SUSPEND_POSSIBLE
1518	def_bool y
1519
1520endmenu
1521
1522menu "CPU Power Management"
1523
1524source "drivers/cpuidle/Kconfig"
1525
1526source "drivers/cpufreq/Kconfig"
1527
1528endmenu
1529
1530source "drivers/firmware/Kconfig"
1531
1532source "drivers/acpi/Kconfig"
1533
1534source "arch/arm64/kvm/Kconfig"
1535
1536if CRYPTO
1537source "arch/arm64/crypto/Kconfig"
1538endif
1539