xref: /openbmc/linux/arch/arm64/Kconfig (revision b60a5b8d)
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 MULTI_IRQ_HANDLER
163	select NEED_DMA_MAP_STATE
164	select NEED_SG_DMA_LENGTH
165	select OF
166	select OF_EARLY_FLATTREE
167	select PCI_DOMAINS_GENERIC if PCI
168	select PCI_ECAM if (ACPI && PCI)
169	select PCI_SYSCALL if PCI
170	select POWER_RESET
171	select POWER_SUPPLY
172	select REFCOUNT_FULL
173	select SPARSE_IRQ
174	select SWIOTLB
175	select SYSCTL_EXCEPTION_TRACE
176	select THREAD_INFO_IN_TASK
177	help
178	  ARM 64-bit (AArch64) Linux support.
179
180config 64BIT
181	def_bool y
182
183config MMU
184	def_bool y
185
186config ARM64_PAGE_SHIFT
187	int
188	default 16 if ARM64_64K_PAGES
189	default 14 if ARM64_16K_PAGES
190	default 12
191
192config ARM64_CONT_SHIFT
193	int
194	default 5 if ARM64_64K_PAGES
195	default 7 if ARM64_16K_PAGES
196	default 4
197
198config ARCH_MMAP_RND_BITS_MIN
199       default 14 if ARM64_64K_PAGES
200       default 16 if ARM64_16K_PAGES
201       default 18
202
203# max bits determined by the following formula:
204#  VA_BITS - PAGE_SHIFT - 3
205config ARCH_MMAP_RND_BITS_MAX
206       default 19 if ARM64_VA_BITS=36
207       default 24 if ARM64_VA_BITS=39
208       default 27 if ARM64_VA_BITS=42
209       default 30 if ARM64_VA_BITS=47
210       default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
211       default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
212       default 33 if ARM64_VA_BITS=48
213       default 14 if ARM64_64K_PAGES
214       default 16 if ARM64_16K_PAGES
215       default 18
216
217config ARCH_MMAP_RND_COMPAT_BITS_MIN
218       default 7 if ARM64_64K_PAGES
219       default 9 if ARM64_16K_PAGES
220       default 11
221
222config ARCH_MMAP_RND_COMPAT_BITS_MAX
223       default 16
224
225config NO_IOPORT_MAP
226	def_bool y if !PCI
227
228config STACKTRACE_SUPPORT
229	def_bool y
230
231config ILLEGAL_POINTER_VALUE
232	hex
233	default 0xdead000000000000
234
235config LOCKDEP_SUPPORT
236	def_bool y
237
238config TRACE_IRQFLAGS_SUPPORT
239	def_bool y
240
241config RWSEM_XCHGADD_ALGORITHM
242	def_bool y
243
244config GENERIC_BUG
245	def_bool y
246	depends on BUG
247
248config GENERIC_BUG_RELATIVE_POINTERS
249	def_bool y
250	depends on GENERIC_BUG
251
252config GENERIC_HWEIGHT
253	def_bool y
254
255config GENERIC_CSUM
256        def_bool y
257
258config GENERIC_CALIBRATE_DELAY
259	def_bool y
260
261config ZONE_DMA32
262	def_bool y
263
264config HAVE_GENERIC_GUP
265	def_bool y
266
267config ARCH_ENABLE_MEMORY_HOTPLUG
268	def_bool y
269
270config SMP
271	def_bool y
272
273config KERNEL_MODE_NEON
274	def_bool y
275
276config FIX_EARLYCON_MEM
277	def_bool y
278
279config PGTABLE_LEVELS
280	int
281	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
282	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
283	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_USER_VA_BITS_52)
284	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
285	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
286	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
287
288config ARCH_SUPPORTS_UPROBES
289	def_bool y
290
291config ARCH_PROC_KCORE_TEXT
292	def_bool y
293
294source "arch/arm64/Kconfig.platforms"
295
296menu "Kernel Features"
297
298menu "ARM errata workarounds via the alternatives framework"
299
300config ARM64_WORKAROUND_CLEAN_CACHE
301	def_bool n
302
303config ARM64_ERRATUM_826319
304	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
305	default y
306	select ARM64_WORKAROUND_CLEAN_CACHE
307	help
308	  This option adds an alternative code sequence to work around ARM
309	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
310	  AXI master interface and an L2 cache.
311
312	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
313	  and is unable to accept a certain write via this interface, it will
314	  not progress on read data presented on the read data channel and the
315	  system can deadlock.
316
317	  The workaround promotes data cache clean instructions to
318	  data cache clean-and-invalidate.
319	  Please note that this does not necessarily enable the workaround,
320	  as it depends on the alternative framework, which will only patch
321	  the kernel if an affected CPU is detected.
322
323	  If unsure, say Y.
324
325config ARM64_ERRATUM_827319
326	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
327	default y
328	select ARM64_WORKAROUND_CLEAN_CACHE
329	help
330	  This option adds an alternative code sequence to work around ARM
331	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
332	  master interface and an L2 cache.
333
334	  Under certain conditions this erratum can cause a clean line eviction
335	  to occur at the same time as another transaction to the same address
336	  on the AMBA 5 CHI interface, which can cause data corruption if the
337	  interconnect reorders the two transactions.
338
339	  The workaround promotes data cache clean instructions to
340	  data cache clean-and-invalidate.
341	  Please note that this does not necessarily enable the workaround,
342	  as it depends on the alternative framework, which will only patch
343	  the kernel if an affected CPU is detected.
344
345	  If unsure, say Y.
346
347config ARM64_ERRATUM_824069
348	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
349	default y
350	select ARM64_WORKAROUND_CLEAN_CACHE
351	help
352	  This option adds an alternative code sequence to work around ARM
353	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
354	  to a coherent interconnect.
355
356	  If a Cortex-A53 processor is executing a store or prefetch for
357	  write instruction at the same time as a processor in another
358	  cluster is executing a cache maintenance operation to the same
359	  address, then this erratum might cause a clean cache line to be
360	  incorrectly marked as dirty.
361
362	  The workaround promotes data cache clean instructions to
363	  data cache clean-and-invalidate.
364	  Please note that this option does not necessarily enable the
365	  workaround, as it depends on the alternative framework, which will
366	  only patch the kernel if an affected CPU is detected.
367
368	  If unsure, say Y.
369
370config ARM64_ERRATUM_819472
371	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
372	default y
373	select ARM64_WORKAROUND_CLEAN_CACHE
374	help
375	  This option adds an alternative code sequence to work around ARM
376	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
377	  present when it is connected to a coherent interconnect.
378
379	  If the processor is executing a load and store exclusive sequence at
380	  the same time as a processor in another cluster is executing a cache
381	  maintenance operation to the same address, then this erratum might
382	  cause data corruption.
383
384	  The workaround promotes data cache clean instructions to
385	  data cache clean-and-invalidate.
386	  Please note that this does not necessarily enable the workaround,
387	  as it depends on the alternative framework, which will only patch
388	  the kernel if an affected CPU is detected.
389
390	  If unsure, say Y.
391
392config ARM64_ERRATUM_832075
393	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
394	default y
395	help
396	  This option adds an alternative code sequence to work around ARM
397	  erratum 832075 on Cortex-A57 parts up to r1p2.
398
399	  Affected Cortex-A57 parts might deadlock when exclusive load/store
400	  instructions to Write-Back memory are mixed with Device loads.
401
402	  The workaround is to promote device loads to use Load-Acquire
403	  semantics.
404	  Please note that this does not necessarily enable the workaround,
405	  as it depends on the alternative framework, which will only patch
406	  the kernel if an affected CPU is detected.
407
408	  If unsure, say Y.
409
410config ARM64_ERRATUM_834220
411	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
412	depends on KVM
413	default y
414	help
415	  This option adds an alternative code sequence to work around ARM
416	  erratum 834220 on Cortex-A57 parts up to r1p2.
417
418	  Affected Cortex-A57 parts might report a Stage 2 translation
419	  fault as the result of a Stage 1 fault for load crossing a
420	  page boundary when there is a permission or device memory
421	  alignment fault at Stage 1 and a translation fault at Stage 2.
422
423	  The workaround is to verify that the Stage 1 translation
424	  doesn't generate a fault before handling the Stage 2 fault.
425	  Please note that this does not necessarily enable the workaround,
426	  as it depends on the alternative framework, which will only patch
427	  the kernel if an affected CPU is detected.
428
429	  If unsure, say Y.
430
431config ARM64_ERRATUM_845719
432	bool "Cortex-A53: 845719: a load might read incorrect data"
433	depends on COMPAT
434	default y
435	help
436	  This option adds an alternative code sequence to work around ARM
437	  erratum 845719 on Cortex-A53 parts up to r0p4.
438
439	  When running a compat (AArch32) userspace on an affected Cortex-A53
440	  part, a load at EL0 from a virtual address that matches the bottom 32
441	  bits of the virtual address used by a recent load at (AArch64) EL1
442	  might return incorrect data.
443
444	  The workaround is to write the contextidr_el1 register on exception
445	  return to a 32-bit task.
446	  Please note that this does not necessarily enable the workaround,
447	  as it depends on the alternative framework, which will only patch
448	  the kernel if an affected CPU is detected.
449
450	  If unsure, say Y.
451
452config ARM64_ERRATUM_843419
453	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
454	default y
455	select ARM64_MODULE_PLTS if MODULES
456	help
457	  This option links the kernel with '--fix-cortex-a53-843419' and
458	  enables PLT support to replace certain ADRP instructions, which can
459	  cause subsequent memory accesses to use an incorrect address on
460	  Cortex-A53 parts up to r0p4.
461
462	  If unsure, say Y.
463
464config ARM64_ERRATUM_1024718
465	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
466	default y
467	help
468	  This option adds work around for Arm Cortex-A55 Erratum 1024718.
469
470	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
471	  update of the hardware dirty bit when the DBM/AP bits are updated
472	  without a break-before-make. The work around is to disable the usage
473	  of hardware DBM locally on the affected cores. CPUs not affected by
474	  erratum will continue to use the feature.
475
476	  If unsure, say Y.
477
478config ARM64_ERRATUM_1188873
479	bool "Cortex-A76: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
480	default y
481	select ARM_ARCH_TIMER_OOL_WORKAROUND
482	help
483	  This option adds work arounds for ARM Cortex-A76 erratum 1188873
484
485	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could cause
486	  register corruption when accessing the timer registers from
487	  AArch32 userspace.
488
489	  If unsure, say Y.
490
491config ARM64_ERRATUM_1165522
492	bool "Cortex-A76: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
493	default y
494	help
495	  This option adds work arounds for ARM Cortex-A76 erratum 1165522
496
497	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
498	  corrupted TLBs by speculating an AT instruction during a guest
499	  context switch.
500
501	  If unsure, say Y.
502
503config ARM64_ERRATUM_1286807
504	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
505	default y
506	select ARM64_WORKAROUND_REPEAT_TLBI
507	help
508	  This option adds workaround for ARM Cortex-A76 erratum 1286807
509
510	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
511	  address for a cacheable mapping of a location is being
512	  accessed by a core while another core is remapping the virtual
513	  address to a new physical page using the recommended
514	  break-before-make sequence, then under very rare circumstances
515	  TLBI+DSB completes before a read using the translation being
516	  invalidated has been observed by other observers. The
517	  workaround repeats the TLBI+DSB operation.
518
519	  If unsure, say Y.
520
521config CAVIUM_ERRATUM_22375
522	bool "Cavium erratum 22375, 24313"
523	default y
524	help
525	  Enable workaround for erratum 22375, 24313.
526
527	  This implements two gicv3-its errata workarounds for ThunderX. Both
528	  with small impact affecting only ITS table allocation.
529
530	    erratum 22375: only alloc 8MB table size
531	    erratum 24313: ignore memory access type
532
533	  The fixes are in ITS initialization and basically ignore memory access
534	  type and table size provided by the TYPER and BASER registers.
535
536	  If unsure, say Y.
537
538config CAVIUM_ERRATUM_23144
539	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
540	depends on NUMA
541	default y
542	help
543	  ITS SYNC command hang for cross node io and collections/cpu mapping.
544
545	  If unsure, say Y.
546
547config CAVIUM_ERRATUM_23154
548	bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
549	default y
550	help
551	  The gicv3 of ThunderX requires a modified version for
552	  reading the IAR status to ensure data synchronization
553	  (access to icc_iar1_el1 is not sync'ed before and after).
554
555	  If unsure, say Y.
556
557config CAVIUM_ERRATUM_27456
558	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
559	default y
560	help
561	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
562	  instructions may cause the icache to become corrupted if it
563	  contains data for a non-current ASID.  The fix is to
564	  invalidate the icache when changing the mm context.
565
566	  If unsure, say Y.
567
568config CAVIUM_ERRATUM_30115
569	bool "Cavium erratum 30115: Guest may disable interrupts in host"
570	default y
571	help
572	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
573	  1.2, and T83 Pass 1.0, KVM guest execution may disable
574	  interrupts in host. Trapping both GICv3 group-0 and group-1
575	  accesses sidesteps the issue.
576
577	  If unsure, say Y.
578
579config QCOM_FALKOR_ERRATUM_1003
580	bool "Falkor E1003: Incorrect translation due to ASID change"
581	default y
582	help
583	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
584	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
585	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
586	  then only for entries in the walk cache, since the leaf translation
587	  is unchanged. Work around the erratum by invalidating the walk cache
588	  entries for the trampoline before entering the kernel proper.
589
590config ARM64_WORKAROUND_REPEAT_TLBI
591	bool
592	help
593	  Enable the repeat TLBI workaround for Falkor erratum 1009 and
594	  Cortex-A76 erratum 1286807.
595
596config QCOM_FALKOR_ERRATUM_1009
597	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
598	default y
599	select ARM64_WORKAROUND_REPEAT_TLBI
600	help
601	  On Falkor v1, the CPU may prematurely complete a DSB following a
602	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
603	  one more time to fix the issue.
604
605	  If unsure, say Y.
606
607config QCOM_QDF2400_ERRATUM_0065
608	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
609	default y
610	help
611	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
612	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
613	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
614
615	  If unsure, say Y.
616
617config SOCIONEXT_SYNQUACER_PREITS
618	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
619	default y
620	help
621	  Socionext Synquacer SoCs implement a separate h/w block to generate
622	  MSI doorbell writes with non-zero values for the device ID.
623
624	  If unsure, say Y.
625
626config HISILICON_ERRATUM_161600802
627	bool "Hip07 161600802: Erroneous redistributor VLPI base"
628	default y
629	help
630	  The HiSilicon Hip07 SoC usees the wrong redistributor base
631	  when issued ITS commands such as VMOVP and VMAPP, and requires
632	  a 128kB offset to be applied to the target address in this commands.
633
634	  If unsure, say Y.
635
636config QCOM_FALKOR_ERRATUM_E1041
637	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
638	default y
639	help
640	  Falkor CPU may speculatively fetch instructions from an improper
641	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
642	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
643
644	  If unsure, say Y.
645
646config FUJITSU_ERRATUM_010001
647	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
648	default y
649	help
650	  This option adds workaround for Fujitsu-A64FX erratum E#010001.
651	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
652	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
653	  This fault occurs under a specific hardware condition when a
654	  load/store instruction performs an address translation using:
655	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
656	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
657	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
658	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
659
660	  The workaround is to ensure these bits are clear in TCR_ELx.
661	  The workaround only affect the Fujitsu-A64FX.
662
663	  If unsure, say Y.
664
665endmenu
666
667
668choice
669	prompt "Page size"
670	default ARM64_4K_PAGES
671	help
672	  Page size (translation granule) configuration.
673
674config ARM64_4K_PAGES
675	bool "4KB"
676	help
677	  This feature enables 4KB pages support.
678
679config ARM64_16K_PAGES
680	bool "16KB"
681	help
682	  The system will use 16KB pages support. AArch32 emulation
683	  requires applications compiled with 16K (or a multiple of 16K)
684	  aligned segments.
685
686config ARM64_64K_PAGES
687	bool "64KB"
688	help
689	  This feature enables 64KB pages support (4KB by default)
690	  allowing only two levels of page tables and faster TLB
691	  look-up. AArch32 emulation requires applications compiled
692	  with 64K aligned segments.
693
694endchoice
695
696choice
697	prompt "Virtual address space size"
698	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
699	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
700	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
701	help
702	  Allows choosing one of multiple possible virtual address
703	  space sizes. The level of translation table is determined by
704	  a combination of page size and virtual address space size.
705
706config ARM64_VA_BITS_36
707	bool "36-bit" if EXPERT
708	depends on ARM64_16K_PAGES
709
710config ARM64_VA_BITS_39
711	bool "39-bit"
712	depends on ARM64_4K_PAGES
713
714config ARM64_VA_BITS_42
715	bool "42-bit"
716	depends on ARM64_64K_PAGES
717
718config ARM64_VA_BITS_47
719	bool "47-bit"
720	depends on ARM64_16K_PAGES
721
722config ARM64_VA_BITS_48
723	bool "48-bit"
724
725config ARM64_USER_VA_BITS_52
726	bool "52-bit (user)"
727	depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
728	help
729	  Enable 52-bit virtual addressing for userspace when explicitly
730	  requested via a hint to mmap(). The kernel will continue to
731	  use 48-bit virtual addresses for its own mappings.
732
733	  NOTE: Enabling 52-bit virtual addressing in conjunction with
734	  ARMv8.3 Pointer Authentication will result in the PAC being
735	  reduced from 7 bits to 3 bits, which may have a significant
736	  impact on its susceptibility to brute-force attacks.
737
738	  If unsure, select 48-bit virtual addressing instead.
739
740endchoice
741
742config ARM64_FORCE_52BIT
743	bool "Force 52-bit virtual addresses for userspace"
744	depends on ARM64_USER_VA_BITS_52 && EXPERT
745	help
746	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
747	  to maintain compatibility with older software by providing 48-bit VAs
748	  unless a hint is supplied to mmap.
749
750	  This configuration option disables the 48-bit compatibility logic, and
751	  forces all userspace addresses to be 52-bit on HW that supports it. One
752	  should only enable this configuration option for stress testing userspace
753	  memory management code. If unsure say N here.
754
755config ARM64_VA_BITS
756	int
757	default 36 if ARM64_VA_BITS_36
758	default 39 if ARM64_VA_BITS_39
759	default 42 if ARM64_VA_BITS_42
760	default 47 if ARM64_VA_BITS_47
761	default 48 if ARM64_VA_BITS_48 || ARM64_USER_VA_BITS_52
762
763choice
764	prompt "Physical address space size"
765	default ARM64_PA_BITS_48
766	help
767	  Choose the maximum physical address range that the kernel will
768	  support.
769
770config ARM64_PA_BITS_48
771	bool "48-bit"
772
773config ARM64_PA_BITS_52
774	bool "52-bit (ARMv8.2)"
775	depends on ARM64_64K_PAGES
776	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
777	help
778	  Enable support for a 52-bit physical address space, introduced as
779	  part of the ARMv8.2-LPA extension.
780
781	  With this enabled, the kernel will also continue to work on CPUs that
782	  do not support ARMv8.2-LPA, but with some added memory overhead (and
783	  minor performance overhead).
784
785endchoice
786
787config ARM64_PA_BITS
788	int
789	default 48 if ARM64_PA_BITS_48
790	default 52 if ARM64_PA_BITS_52
791
792config CPU_BIG_ENDIAN
793       bool "Build big-endian kernel"
794       help
795         Say Y if you plan on running a kernel in big-endian mode.
796
797config SCHED_MC
798	bool "Multi-core scheduler support"
799	help
800	  Multi-core scheduler support improves the CPU scheduler's decision
801	  making when dealing with multi-core CPU chips at a cost of slightly
802	  increased overhead in some places. If unsure say N here.
803
804config SCHED_SMT
805	bool "SMT scheduler support"
806	help
807	  Improves the CPU scheduler's decision making when dealing with
808	  MultiThreading at a cost of slightly increased overhead in some
809	  places. If unsure say N here.
810
811config NR_CPUS
812	int "Maximum number of CPUs (2-4096)"
813	range 2 4096
814	default "256"
815
816config HOTPLUG_CPU
817	bool "Support for hot-pluggable CPUs"
818	select GENERIC_IRQ_MIGRATION
819	help
820	  Say Y here to experiment with turning CPUs off and on.  CPUs
821	  can be controlled through /sys/devices/system/cpu.
822
823# Common NUMA Features
824config NUMA
825	bool "Numa Memory Allocation and Scheduler Support"
826	select ACPI_NUMA if ACPI
827	select OF_NUMA
828	help
829	  Enable NUMA (Non Uniform Memory Access) support.
830
831	  The kernel will try to allocate memory used by a CPU on the
832	  local memory of the CPU and add some more
833	  NUMA awareness to the kernel.
834
835config NODES_SHIFT
836	int "Maximum NUMA Nodes (as a power of 2)"
837	range 1 10
838	default "2"
839	depends on NEED_MULTIPLE_NODES
840	help
841	  Specify the maximum number of NUMA Nodes available on the target
842	  system.  Increases memory reserved to accommodate various tables.
843
844config USE_PERCPU_NUMA_NODE_ID
845	def_bool y
846	depends on NUMA
847
848config HAVE_SETUP_PER_CPU_AREA
849	def_bool y
850	depends on NUMA
851
852config NEED_PER_CPU_EMBED_FIRST_CHUNK
853	def_bool y
854	depends on NUMA
855
856config HOLES_IN_ZONE
857	def_bool y
858
859source "kernel/Kconfig.hz"
860
861config ARCH_SUPPORTS_DEBUG_PAGEALLOC
862	def_bool y
863
864config ARCH_SPARSEMEM_ENABLE
865	def_bool y
866	select SPARSEMEM_VMEMMAP_ENABLE
867
868config ARCH_SPARSEMEM_DEFAULT
869	def_bool ARCH_SPARSEMEM_ENABLE
870
871config ARCH_SELECT_MEMORY_MODEL
872	def_bool ARCH_SPARSEMEM_ENABLE
873
874config ARCH_FLATMEM_ENABLE
875	def_bool !NUMA
876
877config HAVE_ARCH_PFN_VALID
878	def_bool y
879
880config HW_PERF_EVENTS
881	def_bool y
882	depends on ARM_PMU
883
884config SYS_SUPPORTS_HUGETLBFS
885	def_bool y
886
887config ARCH_WANT_HUGE_PMD_SHARE
888	def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
889
890config ARCH_HAS_CACHE_LINE_SIZE
891	def_bool y
892
893config SECCOMP
894	bool "Enable seccomp to safely compute untrusted bytecode"
895	---help---
896	  This kernel feature is useful for number crunching applications
897	  that may need to compute untrusted bytecode during their
898	  execution. By using pipes or other transports made available to
899	  the process as file descriptors supporting the read/write
900	  syscalls, it's possible to isolate those applications in
901	  their own address space using seccomp. Once seccomp is
902	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
903	  and the task is only allowed to execute a few safe syscalls
904	  defined by each seccomp mode.
905
906config PARAVIRT
907	bool "Enable paravirtualization code"
908	help
909	  This changes the kernel so it can modify itself when it is run
910	  under a hypervisor, potentially improving performance significantly
911	  over full virtualization.
912
913config PARAVIRT_TIME_ACCOUNTING
914	bool "Paravirtual steal time accounting"
915	select PARAVIRT
916	default n
917	help
918	  Select this option to enable fine granularity task steal time
919	  accounting. Time spent executing other tasks in parallel with
920	  the current vCPU is discounted from the vCPU power. To account for
921	  that, there can be a small performance impact.
922
923	  If in doubt, say N here.
924
925config KEXEC
926	depends on PM_SLEEP_SMP
927	select KEXEC_CORE
928	bool "kexec system call"
929	---help---
930	  kexec is a system call that implements the ability to shutdown your
931	  current kernel, and to start another kernel.  It is like a reboot
932	  but it is independent of the system firmware.   And like a reboot
933	  you can start any kernel with it, not just Linux.
934
935config KEXEC_FILE
936	bool "kexec file based system call"
937	select KEXEC_CORE
938	help
939	  This is new version of kexec system call. This system call is
940	  file based and takes file descriptors as system call argument
941	  for kernel and initramfs as opposed to list of segments as
942	  accepted by previous system call.
943
944config KEXEC_VERIFY_SIG
945	bool "Verify kernel signature during kexec_file_load() syscall"
946	depends on KEXEC_FILE
947	help
948	  Select this option to verify a signature with loaded kernel
949	  image. If configured, any attempt of loading a image without
950	  valid signature will fail.
951
952	  In addition to that option, you need to enable signature
953	  verification for the corresponding kernel image type being
954	  loaded in order for this to work.
955
956config KEXEC_IMAGE_VERIFY_SIG
957	bool "Enable Image signature verification support"
958	default y
959	depends on KEXEC_VERIFY_SIG
960	depends on EFI && SIGNED_PE_FILE_VERIFICATION
961	help
962	  Enable Image signature verification support.
963
964comment "Support for PE file signature verification disabled"
965	depends on KEXEC_VERIFY_SIG
966	depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
967
968config CRASH_DUMP
969	bool "Build kdump crash kernel"
970	help
971	  Generate crash dump after being started by kexec. This should
972	  be normally only set in special crash dump kernels which are
973	  loaded in the main kernel with kexec-tools into a specially
974	  reserved region and then later executed after a crash by
975	  kdump/kexec.
976
977	  For more details see Documentation/kdump/kdump.txt
978
979config XEN_DOM0
980	def_bool y
981	depends on XEN
982
983config XEN
984	bool "Xen guest support on ARM64"
985	depends on ARM64 && OF
986	select SWIOTLB_XEN
987	select PARAVIRT
988	help
989	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
990
991config FORCE_MAX_ZONEORDER
992	int
993	default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
994	default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
995	default "11"
996	help
997	  The kernel memory allocator divides physically contiguous memory
998	  blocks into "zones", where each zone is a power of two number of
999	  pages.  This option selects the largest power of two that the kernel
1000	  keeps in the memory allocator.  If you need to allocate very large
1001	  blocks of physically contiguous memory, then you may need to
1002	  increase this value.
1003
1004	  This config option is actually maximum order plus one. For example,
1005	  a value of 11 means that the largest free memory block is 2^10 pages.
1006
1007	  We make sure that we can allocate upto a HugePage size for each configuration.
1008	  Hence we have :
1009		MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
1010
1011	  However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
1012	  4M allocations matching the default size used by generic code.
1013
1014config UNMAP_KERNEL_AT_EL0
1015	bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
1016	default y
1017	help
1018	  Speculation attacks against some high-performance processors can
1019	  be used to bypass MMU permission checks and leak kernel data to
1020	  userspace. This can be defended against by unmapping the kernel
1021	  when running in userspace, mapping it back in on exception entry
1022	  via a trampoline page in the vector table.
1023
1024	  If unsure, say Y.
1025
1026config HARDEN_BRANCH_PREDICTOR
1027	bool "Harden the branch predictor against aliasing attacks" if EXPERT
1028	default y
1029	help
1030	  Speculation attacks against some high-performance processors rely on
1031	  being able to manipulate the branch predictor for a victim context by
1032	  executing aliasing branches in the attacker context.  Such attacks
1033	  can be partially mitigated against by clearing internal branch
1034	  predictor state and limiting the prediction logic in some situations.
1035
1036	  This config option will take CPU-specific actions to harden the
1037	  branch predictor against aliasing attacks and may rely on specific
1038	  instruction sequences or control bits being set by the system
1039	  firmware.
1040
1041	  If unsure, say Y.
1042
1043config HARDEN_EL2_VECTORS
1044	bool "Harden EL2 vector mapping against system register leak" if EXPERT
1045	default y
1046	help
1047	  Speculation attacks against some high-performance processors can
1048	  be used to leak privileged information such as the vector base
1049	  register, resulting in a potential defeat of the EL2 layout
1050	  randomization.
1051
1052	  This config option will map the vectors to a fixed location,
1053	  independent of the EL2 code mapping, so that revealing VBAR_EL2
1054	  to an attacker does not give away any extra information. This
1055	  only gets enabled on affected CPUs.
1056
1057	  If unsure, say Y.
1058
1059config ARM64_SSBD
1060	bool "Speculative Store Bypass Disable" if EXPERT
1061	default y
1062	help
1063	  This enables mitigation of the bypassing of previous stores
1064	  by speculative loads.
1065
1066	  If unsure, say Y.
1067
1068config RODATA_FULL_DEFAULT_ENABLED
1069	bool "Apply r/o permissions of VM areas also to their linear aliases"
1070	default y
1071	help
1072	  Apply read-only attributes of VM areas to the linear alias of
1073	  the backing pages as well. This prevents code or read-only data
1074	  from being modified (inadvertently or intentionally) via another
1075	  mapping of the same memory page. This additional enhancement can
1076	  be turned off at runtime by passing rodata=[off|on] (and turned on
1077	  with rodata=full if this option is set to 'n')
1078
1079	  This requires the linear region to be mapped down to pages,
1080	  which may adversely affect performance in some cases.
1081
1082menuconfig ARMV8_DEPRECATED
1083	bool "Emulate deprecated/obsolete ARMv8 instructions"
1084	depends on COMPAT
1085	depends on SYSCTL
1086	help
1087	  Legacy software support may require certain instructions
1088	  that have been deprecated or obsoleted in the architecture.
1089
1090	  Enable this config to enable selective emulation of these
1091	  features.
1092
1093	  If unsure, say Y
1094
1095if ARMV8_DEPRECATED
1096
1097config SWP_EMULATION
1098	bool "Emulate SWP/SWPB instructions"
1099	help
1100	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1101	  they are always undefined. Say Y here to enable software
1102	  emulation of these instructions for userspace using LDXR/STXR.
1103
1104	  In some older versions of glibc [<=2.8] SWP is used during futex
1105	  trylock() operations with the assumption that the code will not
1106	  be preempted. This invalid assumption may be more likely to fail
1107	  with SWP emulation enabled, leading to deadlock of the user
1108	  application.
1109
1110	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1111	  on an external transaction monitoring block called a global
1112	  monitor to maintain update atomicity. If your system does not
1113	  implement a global monitor, this option can cause programs that
1114	  perform SWP operations to uncached memory to deadlock.
1115
1116	  If unsure, say Y
1117
1118config CP15_BARRIER_EMULATION
1119	bool "Emulate CP15 Barrier instructions"
1120	help
1121	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1122	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1123	  strongly recommended to use the ISB, DSB, and DMB
1124	  instructions instead.
1125
1126	  Say Y here to enable software emulation of these
1127	  instructions for AArch32 userspace code. When this option is
1128	  enabled, CP15 barrier usage is traced which can help
1129	  identify software that needs updating.
1130
1131	  If unsure, say Y
1132
1133config SETEND_EMULATION
1134	bool "Emulate SETEND instruction"
1135	help
1136	  The SETEND instruction alters the data-endianness of the
1137	  AArch32 EL0, and is deprecated in ARMv8.
1138
1139	  Say Y here to enable software emulation of the instruction
1140	  for AArch32 userspace code.
1141
1142	  Note: All the cpus on the system must have mixed endian support at EL0
1143	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1144	  endian - is hotplugged in after this feature has been enabled, there could
1145	  be unexpected results in the applications.
1146
1147	  If unsure, say Y
1148endif
1149
1150config ARM64_SW_TTBR0_PAN
1151	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1152	help
1153	  Enabling this option prevents the kernel from accessing
1154	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1155	  zeroed area and reserved ASID. The user access routines
1156	  restore the valid TTBR0_EL1 temporarily.
1157
1158menu "ARMv8.1 architectural features"
1159
1160config ARM64_HW_AFDBM
1161	bool "Support for hardware updates of the Access and Dirty page flags"
1162	default y
1163	help
1164	  The ARMv8.1 architecture extensions introduce support for
1165	  hardware updates of the access and dirty information in page
1166	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1167	  capable processors, accesses to pages with PTE_AF cleared will
1168	  set this bit instead of raising an access flag fault.
1169	  Similarly, writes to read-only pages with the DBM bit set will
1170	  clear the read-only bit (AP[2]) instead of raising a
1171	  permission fault.
1172
1173	  Kernels built with this configuration option enabled continue
1174	  to work on pre-ARMv8.1 hardware and the performance impact is
1175	  minimal. If unsure, say Y.
1176
1177config ARM64_PAN
1178	bool "Enable support for Privileged Access Never (PAN)"
1179	default y
1180	help
1181	 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1182	 prevents the kernel or hypervisor from accessing user-space (EL0)
1183	 memory directly.
1184
1185	 Choosing this option will cause any unprotected (not using
1186	 copy_to_user et al) memory access to fail with a permission fault.
1187
1188	 The feature is detected at runtime, and will remain as a 'nop'
1189	 instruction if the cpu does not implement the feature.
1190
1191config ARM64_LSE_ATOMICS
1192	bool "Atomic instructions"
1193	default y
1194	help
1195	  As part of the Large System Extensions, ARMv8.1 introduces new
1196	  atomic instructions that are designed specifically to scale in
1197	  very large systems.
1198
1199	  Say Y here to make use of these instructions for the in-kernel
1200	  atomic routines. This incurs a small overhead on CPUs that do
1201	  not support these instructions and requires the kernel to be
1202	  built with binutils >= 2.25 in order for the new instructions
1203	  to be used.
1204
1205config ARM64_VHE
1206	bool "Enable support for Virtualization Host Extensions (VHE)"
1207	default y
1208	help
1209	  Virtualization Host Extensions (VHE) allow the kernel to run
1210	  directly at EL2 (instead of EL1) on processors that support
1211	  it. This leads to better performance for KVM, as they reduce
1212	  the cost of the world switch.
1213
1214	  Selecting this option allows the VHE feature to be detected
1215	  at runtime, and does not affect processors that do not
1216	  implement this feature.
1217
1218endmenu
1219
1220menu "ARMv8.2 architectural features"
1221
1222config ARM64_UAO
1223	bool "Enable support for User Access Override (UAO)"
1224	default y
1225	help
1226	  User Access Override (UAO; part of the ARMv8.2 Extensions)
1227	  causes the 'unprivileged' variant of the load/store instructions to
1228	  be overridden to be privileged.
1229
1230	  This option changes get_user() and friends to use the 'unprivileged'
1231	  variant of the load/store instructions. This ensures that user-space
1232	  really did have access to the supplied memory. When addr_limit is
1233	  set to kernel memory the UAO bit will be set, allowing privileged
1234	  access to kernel memory.
1235
1236	  Choosing this option will cause copy_to_user() et al to use user-space
1237	  memory permissions.
1238
1239	  The feature is detected at runtime, the kernel will use the
1240	  regular load/store instructions if the cpu does not implement the
1241	  feature.
1242
1243config ARM64_PMEM
1244	bool "Enable support for persistent memory"
1245	select ARCH_HAS_PMEM_API
1246	select ARCH_HAS_UACCESS_FLUSHCACHE
1247	help
1248	  Say Y to enable support for the persistent memory API based on the
1249	  ARMv8.2 DCPoP feature.
1250
1251	  The feature is detected at runtime, and the kernel will use DC CVAC
1252	  operations if DC CVAP is not supported (following the behaviour of
1253	  DC CVAP itself if the system does not define a point of persistence).
1254
1255config ARM64_RAS_EXTN
1256	bool "Enable support for RAS CPU Extensions"
1257	default y
1258	help
1259	  CPUs that support the Reliability, Availability and Serviceability
1260	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1261	  errors, classify them and report them to software.
1262
1263	  On CPUs with these extensions system software can use additional
1264	  barriers to determine if faults are pending and read the
1265	  classification from a new set of registers.
1266
1267	  Selecting this feature will allow the kernel to use these barriers
1268	  and access the new registers if the system supports the extension.
1269	  Platform RAS features may additionally depend on firmware support.
1270
1271config ARM64_CNP
1272	bool "Enable support for Common Not Private (CNP) translations"
1273	default y
1274	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1275	help
1276	  Common Not Private (CNP) allows translation table entries to
1277	  be shared between different PEs in the same inner shareable
1278	  domain, so the hardware can use this fact to optimise the
1279	  caching of such entries in the TLB.
1280
1281	  Selecting this option allows the CNP feature to be detected
1282	  at runtime, and does not affect PEs that do not implement
1283	  this feature.
1284
1285endmenu
1286
1287menu "ARMv8.3 architectural features"
1288
1289config ARM64_PTR_AUTH
1290	bool "Enable support for pointer authentication"
1291	default y
1292	help
1293	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1294	  instructions for signing and authenticating pointers against secret
1295	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1296	  and other attacks.
1297
1298	  This option enables these instructions at EL0 (i.e. for userspace).
1299
1300	  Choosing this option will cause the kernel to initialise secret keys
1301	  for each process at exec() time, with these keys being
1302	  context-switched along with the process.
1303
1304	  The feature is detected at runtime. If the feature is not present in
1305	  hardware it will not be advertised to userspace nor will it be
1306	  enabled.
1307
1308endmenu
1309
1310config ARM64_SVE
1311	bool "ARM Scalable Vector Extension support"
1312	default y
1313	depends on !KVM || ARM64_VHE
1314	help
1315	  The Scalable Vector Extension (SVE) is an extension to the AArch64
1316	  execution state which complements and extends the SIMD functionality
1317	  of the base architecture to support much larger vectors and to enable
1318	  additional vectorisation opportunities.
1319
1320	  To enable use of this extension on CPUs that implement it, say Y.
1321
1322	  Note that for architectural reasons, firmware _must_ implement SVE
1323	  support when running on SVE capable hardware.  The required support
1324	  is present in:
1325
1326	    * version 1.5 and later of the ARM Trusted Firmware
1327	    * the AArch64 boot wrapper since commit 5e1261e08abf
1328	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
1329
1330	  For other firmware implementations, consult the firmware documentation
1331	  or vendor.
1332
1333	  If you need the kernel to boot on SVE-capable hardware with broken
1334	  firmware, you may need to say N here until you get your firmware
1335	  fixed.  Otherwise, you may experience firmware panics or lockups when
1336	  booting the kernel.  If unsure and you are not observing these
1337	  symptoms, you should assume that it is safe to say Y.
1338
1339	  CPUs that support SVE are architecturally required to support the
1340	  Virtualization Host Extensions (VHE), so the kernel makes no
1341	  provision for supporting SVE alongside KVM without VHE enabled.
1342	  Thus, you will need to enable CONFIG_ARM64_VHE if you want to support
1343	  KVM in the same kernel image.
1344
1345config ARM64_MODULE_PLTS
1346	bool
1347	select HAVE_MOD_ARCH_SPECIFIC
1348
1349config ARM64_PSEUDO_NMI
1350	bool "Support for NMI-like interrupts"
1351	select CONFIG_ARM_GIC_V3
1352	help
1353	  Adds support for mimicking Non-Maskable Interrupts through the use of
1354	  GIC interrupt priority. This support requires version 3 or later of
1355	  Arm GIC.
1356
1357	  This high priority configuration for interrupts needs to be
1358	  explicitly enabled by setting the kernel parameter
1359	  "irqchip.gicv3_pseudo_nmi" to 1.
1360
1361	  If unsure, say N
1362
1363config RELOCATABLE
1364	bool
1365	help
1366	  This builds the kernel as a Position Independent Executable (PIE),
1367	  which retains all relocation metadata required to relocate the
1368	  kernel binary at runtime to a different virtual address than the
1369	  address it was linked at.
1370	  Since AArch64 uses the RELA relocation format, this requires a
1371	  relocation pass at runtime even if the kernel is loaded at the
1372	  same address it was linked at.
1373
1374config RANDOMIZE_BASE
1375	bool "Randomize the address of the kernel image"
1376	select ARM64_MODULE_PLTS if MODULES
1377	select RELOCATABLE
1378	help
1379	  Randomizes the virtual address at which the kernel image is
1380	  loaded, as a security feature that deters exploit attempts
1381	  relying on knowledge of the location of kernel internals.
1382
1383	  It is the bootloader's job to provide entropy, by passing a
1384	  random u64 value in /chosen/kaslr-seed at kernel entry.
1385
1386	  When booting via the UEFI stub, it will invoke the firmware's
1387	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1388	  to the kernel proper. In addition, it will randomise the physical
1389	  location of the kernel Image as well.
1390
1391	  If unsure, say N.
1392
1393config RANDOMIZE_MODULE_REGION_FULL
1394	bool "Randomize the module region over a 4 GB range"
1395	depends on RANDOMIZE_BASE
1396	default y
1397	help
1398	  Randomizes the location of the module region inside a 4 GB window
1399	  covering the core kernel. This way, it is less likely for modules
1400	  to leak information about the location of core kernel data structures
1401	  but it does imply that function calls between modules and the core
1402	  kernel will need to be resolved via veneers in the module PLT.
1403
1404	  When this option is not set, the module region will be randomized over
1405	  a limited range that contains the [_stext, _etext] interval of the
1406	  core kernel, so branch relocations are always in range.
1407
1408config CC_HAVE_STACKPROTECTOR_SYSREG
1409	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
1410
1411config STACKPROTECTOR_PER_TASK
1412	def_bool y
1413	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
1414
1415endmenu
1416
1417menu "Boot options"
1418
1419config ARM64_ACPI_PARKING_PROTOCOL
1420	bool "Enable support for the ARM64 ACPI parking protocol"
1421	depends on ACPI
1422	help
1423	  Enable support for the ARM64 ACPI parking protocol. If disabled
1424	  the kernel will not allow booting through the ARM64 ACPI parking
1425	  protocol even if the corresponding data is present in the ACPI
1426	  MADT table.
1427
1428config CMDLINE
1429	string "Default kernel command string"
1430	default ""
1431	help
1432	  Provide a set of default command-line options at build time by
1433	  entering them here. As a minimum, you should specify the the
1434	  root device (e.g. root=/dev/nfs).
1435
1436config CMDLINE_FORCE
1437	bool "Always use the default kernel command string"
1438	help
1439	  Always use the default kernel command string, even if the boot
1440	  loader passes other arguments to the kernel.
1441	  This is useful if you cannot or don't want to change the
1442	  command-line options your boot loader passes to the kernel.
1443
1444config EFI_STUB
1445	bool
1446
1447config EFI
1448	bool "UEFI runtime support"
1449	depends on OF && !CPU_BIG_ENDIAN
1450	depends on KERNEL_MODE_NEON
1451	select ARCH_SUPPORTS_ACPI
1452	select LIBFDT
1453	select UCS2_STRING
1454	select EFI_PARAMS_FROM_FDT
1455	select EFI_RUNTIME_WRAPPERS
1456	select EFI_STUB
1457	select EFI_ARMSTUB
1458	default y
1459	help
1460	  This option provides support for runtime services provided
1461	  by UEFI firmware (such as non-volatile variables, realtime
1462          clock, and platform reset). A UEFI stub is also provided to
1463	  allow the kernel to be booted as an EFI application. This
1464	  is only useful on systems that have UEFI firmware.
1465
1466config DMI
1467	bool "Enable support for SMBIOS (DMI) tables"
1468	depends on EFI
1469	default y
1470	help
1471	  This enables SMBIOS/DMI feature for systems.
1472
1473	  This option is only useful on systems that have UEFI firmware.
1474	  However, even with this option, the resultant kernel should
1475	  continue to boot on existing non-UEFI platforms.
1476
1477endmenu
1478
1479config COMPAT
1480	bool "Kernel support for 32-bit EL0"
1481	depends on ARM64_4K_PAGES || EXPERT
1482	select COMPAT_BINFMT_ELF if BINFMT_ELF
1483	select HAVE_UID16
1484	select OLD_SIGSUSPEND3
1485	select COMPAT_OLD_SIGACTION
1486	help
1487	  This option enables support for a 32-bit EL0 running under a 64-bit
1488	  kernel at EL1. AArch32-specific components such as system calls,
1489	  the user helper functions, VFP support and the ptrace interface are
1490	  handled appropriately by the kernel.
1491
1492	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1493	  that you will only be able to execute AArch32 binaries that were compiled
1494	  with page size aligned segments.
1495
1496	  If you want to execute 32-bit userspace applications, say Y.
1497
1498config SYSVIPC_COMPAT
1499	def_bool y
1500	depends on COMPAT && SYSVIPC
1501
1502config ARCH_ENABLE_HUGEPAGE_MIGRATION
1503	def_bool y
1504	depends on HUGETLB_PAGE && MIGRATION
1505
1506menu "Power management options"
1507
1508source "kernel/power/Kconfig"
1509
1510config ARCH_HIBERNATION_POSSIBLE
1511	def_bool y
1512	depends on CPU_PM
1513
1514config ARCH_HIBERNATION_HEADER
1515	def_bool y
1516	depends on HIBERNATION
1517
1518config ARCH_SUSPEND_POSSIBLE
1519	def_bool y
1520
1521endmenu
1522
1523menu "CPU Power Management"
1524
1525source "drivers/cpuidle/Kconfig"
1526
1527source "drivers/cpufreq/Kconfig"
1528
1529endmenu
1530
1531source "drivers/firmware/Kconfig"
1532
1533source "drivers/acpi/Kconfig"
1534
1535source "arch/arm64/kvm/Kconfig"
1536
1537if CRYPTO
1538source "arch/arm64/crypto/Kconfig"
1539endif
1540