blob: 105283b01a534cd07d35328109cb22ec568310b5 [file] [log] [blame]
xjb04a4022021-11-25 15:01:52 +08001config 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
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_ACPI_TABLE_UPGRADE if ACPI
15 select ARCH_HAS_ELF_RANDOMIZE
16 select ARCH_HAS_FAST_MULTIPLIER
17 select ARCH_HAS_FORTIFY_SOURCE
18 select ARCH_HAS_GCOV_PROFILE_ALL
19 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
20 select ARCH_HAS_KCOV
21 select ARCH_HAS_MEMBARRIER_SYNC_CORE
22 select ARCH_HAS_PTE_SPECIAL
23 select ARCH_HAS_SET_MEMORY
24 select ARCH_HAS_SG_CHAIN
25 select ARCH_HAS_STRICT_KERNEL_RWX
26 select ARCH_HAS_STRICT_MODULE_RWX
27 select ARCH_HAS_SYSCALL_WRAPPER
28 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
29 select ARCH_HAVE_NMI_SAFE_CMPXCHG
30 select ARCH_INLINE_READ_LOCK if !PREEMPT
31 select ARCH_INLINE_READ_LOCK_BH if !PREEMPT
32 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPT
33 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPT
34 select ARCH_INLINE_READ_UNLOCK if !PREEMPT
35 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPT
36 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPT
37 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPT
38 select ARCH_INLINE_WRITE_LOCK if !PREEMPT
39 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPT
40 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPT
41 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPT
42 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPT
43 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPT
44 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPT
45 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPT
46 select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPT
47 select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPT
48 select ARCH_INLINE_SPIN_LOCK if !PREEMPT
49 select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPT
50 select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPT
51 select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPT
52 select ARCH_INLINE_SPIN_UNLOCK if !PREEMPT
53 select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPT
54 select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPT
55 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPT
56 select ARCH_USE_CMPXCHG_LOCKREF
57 select ARCH_USE_QUEUED_RWLOCKS
58 select ARCH_USE_QUEUED_SPINLOCKS
59 select ARCH_SUPPORTS_MEMORY_FAILURE
60 select ARCH_SUPPORTS_LTO_CLANG
61 select ARCH_SUPPORTS_THINLTO
62 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
63 select ARCH_SUPPORTS_ATOMIC_RMW
64 select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 || CC_IS_CLANG
65 select ARCH_SUPPORTS_NUMA_BALANCING
66 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
67 select ARCH_WANT_FRAME_POINTERS
68 select ARCH_HAS_UBSAN_SANITIZE_ALL
69 select ARM_AMBA
70 select ARM_ARCH_TIMER
71 select ARM_GIC
72 select AUDIT_ARCH_COMPAT_GENERIC
73 select ARM_GIC_V2M if PCI
74 select ARM_GIC_V3
75 select ARM_GIC_V3_ITS if PCI
76 select ARM_PSCI_FW
77 select BUILDTIME_EXTABLE_SORT
78 select CLONE_BACKWARDS
79 select COMMON_CLK
80 select CPU_PM if (SUSPEND || CPU_IDLE)
81 select DCACHE_WORD_ACCESS
82 select DMA_DIRECT_OPS
83 select EDAC_SUPPORT
84 select FRAME_POINTER
85 select GENERIC_ALLOCATOR
86 select GENERIC_ARCH_TOPOLOGY
87 select GENERIC_CLOCKEVENTS
88 select GENERIC_CLOCKEVENTS_BROADCAST
89 select GENERIC_CPU_AUTOPROBE
90 select GENERIC_CPU_VULNERABILITIES
91 select GENERIC_EARLY_IOREMAP
92 select GENERIC_IDLE_POLL_SETUP
93 select GENERIC_IRQ_MULTI_HANDLER
94 select GENERIC_IRQ_PROBE
95 select GENERIC_IRQ_SHOW
96 select GENERIC_IRQ_SHOW_LEVEL
97 select GENERIC_PCI_IOMAP
98 select GENERIC_SCHED_CLOCK
99 select GENERIC_SMP_IDLE_THREAD
100 select GENERIC_STRNCPY_FROM_USER
101 select GENERIC_STRNLEN_USER
102 select GENERIC_TIME_VSYSCALL
103 select HANDLE_DOMAIN_IRQ
104 select HARDIRQS_SW_RESEND
105 select HAVE_ACPI_APEI if (ACPI && EFI)
106 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
107 select HAVE_ARCH_AUDITSYSCALL
108 select HAVE_ARCH_BITREVERSE
109 select HAVE_ARCH_HUGE_VMAP
110 select HAVE_ARCH_JUMP_LABEL
111 select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
112 select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
113 select HAVE_ARCH_KGDB
114 select HAVE_ARCH_MMAP_RND_BITS
115 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
116 select HAVE_ARCH_PREL32_RELOCATIONS if !LTO_CLANG
117 select HAVE_ARCH_SECCOMP_FILTER
118 select HAVE_ARCH_STACKLEAK
119 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
120 select HAVE_ARCH_TRACEHOOK
121 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
122 select HAVE_ARCH_VMAP_STACK
123 select HAVE_ARM_SMCCC
124 select HAVE_EBPF_JIT
125 select HAVE_C_RECORDMCOUNT
126 select HAVE_CMPXCHG_DOUBLE
127 select HAVE_CMPXCHG_LOCAL
128 select HAVE_CONTEXT_TRACKING
129 select HAVE_DEBUG_BUGVERBOSE
130 select HAVE_DEBUG_KMEMLEAK
131 select HAVE_DMA_CONTIGUOUS
132 select HAVE_DYNAMIC_FTRACE
133 select HAVE_EFFICIENT_UNALIGNED_ACCESS
134 select HAVE_FTRACE_MCOUNT_RECORD
135 select HAVE_FUNCTION_TRACER
136 select HAVE_FUNCTION_GRAPH_TRACER if !SHADOW_CALL_STACK
137 select HAVE_GCC_PLUGINS
138 select HAVE_GENERIC_DMA_COHERENT
139 select HAVE_HW_BREAKPOINT if PERF_EVENTS
140 select HAVE_IRQ_TIME_ACCOUNTING
141 select HAVE_MEMBLOCK
142 select HAVE_MEMBLOCK_NODE_MAP if NUMA
143 select HAVE_NMI
144 select HAVE_PATA_PLATFORM
145 select HAVE_PERF_EVENTS
146 select HAVE_PERF_REGS
147 select HAVE_PERF_USER_STACK_DUMP
148 select HAVE_REGS_AND_STACK_ACCESS_API
149 select HAVE_RCU_TABLE_FREE
150 select HAVE_RSEQ
151 select HAVE_STACKPROTECTOR
152 select HAVE_SYSCALL_TRACEPOINTS
153 select HAVE_KPROBES
154 select HAVE_KRETPROBES
155 select IOMMU_DMA if IOMMU_SUPPORT
156 select IRQ_DOMAIN
157 select IRQ_FORCED_THREADING
158 select MODULES_USE_ELF_RELA
159 select MULTI_IRQ_HANDLER
160 select NEED_DMA_MAP_STATE
161 select NEED_SG_DMA_LENGTH
162 select NO_BOOTMEM
163 select OF
164 select OF_EARLY_FLATTREE
165 select OF_RESERVED_MEM
166 select PCI_ECAM if ACPI
167 select POWER_RESET
168 select POWER_SUPPLY
169 select REFCOUNT_FULL
170 select SPARSE_IRQ
171 select SWIOTLB
172 select SYSCTL_EXCEPTION_TRACE
173 select THREAD_INFO_IN_TASK
174 help
175 ARM 64-bit (AArch64) Linux support.
176
177config 64BIT
178 def_bool y
179
180config MMU
181 def_bool y
182
183config ARM64_PAGE_SHIFT
184 int
185 default 16 if ARM64_64K_PAGES
186 default 14 if ARM64_16K_PAGES
187 default 12
188
189config ARM64_CONT_SHIFT
190 int
191 default 5 if ARM64_64K_PAGES
192 default 7 if ARM64_16K_PAGES
193 default 4
194
195config ARCH_MMAP_RND_BITS_MIN
196 default 14 if ARM64_64K_PAGES
197 default 16 if ARM64_16K_PAGES
198 default 18
199
200# max bits determined by the following formula:
201# VA_BITS - PAGE_SHIFT - 3
202config ARCH_MMAP_RND_BITS_MAX
203 default 19 if ARM64_VA_BITS=36
204 default 24 if ARM64_VA_BITS=39
205 default 27 if ARM64_VA_BITS=42
206 default 30 if ARM64_VA_BITS=47
207 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
208 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
209 default 33 if ARM64_VA_BITS=48
210 default 14 if ARM64_64K_PAGES
211 default 16 if ARM64_16K_PAGES
212 default 18
213
214config ARCH_MMAP_RND_COMPAT_BITS_MIN
215 default 7 if ARM64_64K_PAGES
216 default 9 if ARM64_16K_PAGES
217 default 11
218
219config ARCH_MMAP_RND_COMPAT_BITS_MAX
220 default 16
221
222config NO_IOPORT_MAP
223 def_bool y if !PCI
224
225config STACKTRACE_SUPPORT
226 def_bool y
227
228config ILLEGAL_POINTER_VALUE
229 hex
230 default 0xdead000000000000
231
232config LOCKDEP_SUPPORT
233 def_bool y
234
235config TRACE_IRQFLAGS_SUPPORT
236 def_bool y
237
238config RWSEM_XCHGADD_ALGORITHM
239 def_bool y
240
241config GENERIC_BUG
242 def_bool y
243 depends on BUG
244
245config GENERIC_BUG_RELATIVE_POINTERS
246 def_bool y
247 depends on GENERIC_BUG
248
249config GENERIC_HWEIGHT
250 def_bool y
251
252config GENERIC_CSUM
253 def_bool y
254
255config GENERIC_CALIBRATE_DELAY
256 def_bool y
257
258config ZONE_DMA32
259 bool "Support DMA32 zone" if EXPERT
260 default y
261
262config HAVE_GENERIC_GUP
263 def_bool y
264
265config SMP
266 def_bool y
267
268config KERNEL_MODE_NEON
269 def_bool y
270
271config FIX_EARLYCON_MEM
272 def_bool y
273
274config PGTABLE_LEVELS
275 int
276 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
277 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
278 default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48
279 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
280 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
281 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
282
283config ARCH_SUPPORTS_UPROBES
284 def_bool y
285
286config ARCH_PROC_KCORE_TEXT
287 def_bool y
288
289source "arch/arm64/Kconfig.platforms"
290
291menu "Bus support"
292
293config PCI
294 bool "PCI support"
295 help
296 This feature enables support for PCI bus system. If you say Y
297 here, the kernel will include drivers and infrastructure code
298 to support PCI bus devices.
299
300config PCI_DOMAINS
301 def_bool PCI
302
303config PCI_DOMAINS_GENERIC
304 def_bool PCI
305
306config PCI_SYSCALL
307 def_bool PCI
308
309source "drivers/pci/Kconfig"
310
311endmenu
312
313menu "Kernel Features"
314
315menu "ARM errata workarounds via the alternatives framework"
316
317config ARM64_ERRATUM_826319
318 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
319 default y
320 help
321 This option adds an alternative code sequence to work around ARM
322 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
323 AXI master interface and an L2 cache.
324
325 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
326 and is unable to accept a certain write via this interface, it will
327 not progress on read data presented on the read data channel and the
328 system can deadlock.
329
330 The workaround promotes data cache clean instructions to
331 data cache clean-and-invalidate.
332 Please note that this does not necessarily enable the workaround,
333 as it depends on the alternative framework, which will only patch
334 the kernel if an affected CPU is detected.
335
336 If unsure, say Y.
337
338config ARM64_ERRATUM_827319
339 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
340 default y
341 help
342 This option adds an alternative code sequence to work around ARM
343 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
344 master interface and an L2 cache.
345
346 Under certain conditions this erratum can cause a clean line eviction
347 to occur at the same time as another transaction to the same address
348 on the AMBA 5 CHI interface, which can cause data corruption if the
349 interconnect reorders the two transactions.
350
351 The workaround promotes data cache clean instructions to
352 data cache clean-and-invalidate.
353 Please note that this does not necessarily enable the workaround,
354 as it depends on the alternative framework, which will only patch
355 the kernel if an affected CPU is detected.
356
357 If unsure, say Y.
358
359config ARM64_ERRATUM_824069
360 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
361 default y
362 help
363 This option adds an alternative code sequence to work around ARM
364 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
365 to a coherent interconnect.
366
367 If a Cortex-A53 processor is executing a store or prefetch for
368 write instruction at the same time as a processor in another
369 cluster is executing a cache maintenance operation to the same
370 address, then this erratum might cause a clean cache line to be
371 incorrectly marked as dirty.
372
373 The workaround promotes data cache clean instructions to
374 data cache clean-and-invalidate.
375 Please note that this option does not necessarily enable the
376 workaround, as it depends on the alternative framework, which will
377 only patch the kernel if an affected CPU is detected.
378
379 If unsure, say Y.
380
381config ARM64_ERRATUM_819472
382 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
383 default y
384 help
385 This option adds an alternative code sequence to work around ARM
386 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
387 present when it is connected to a coherent interconnect.
388
389 If the processor is executing a load and store exclusive sequence at
390 the same time as a processor in another cluster is executing a cache
391 maintenance operation to the same address, then this erratum might
392 cause data corruption.
393
394 The workaround promotes data cache clean instructions to
395 data cache clean-and-invalidate.
396 Please note that this does not necessarily enable the workaround,
397 as it depends on the alternative framework, which will only patch
398 the kernel if an affected CPU is detected.
399
400 If unsure, say Y.
401
402config ARM64_ERRATUM_832075
403 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
404 default y
405 help
406 This option adds an alternative code sequence to work around ARM
407 erratum 832075 on Cortex-A57 parts up to r1p2.
408
409 Affected Cortex-A57 parts might deadlock when exclusive load/store
410 instructions to Write-Back memory are mixed with Device loads.
411
412 The workaround is to promote device loads to use Load-Acquire
413 semantics.
414 Please note that this does not necessarily enable the workaround,
415 as it depends on the alternative framework, which will only patch
416 the kernel if an affected CPU is detected.
417
418 If unsure, say Y.
419
420config ARM64_ERRATUM_834220
421 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
422 depends on KVM
423 default y
424 help
425 This option adds an alternative code sequence to work around ARM
426 erratum 834220 on Cortex-A57 parts up to r1p2.
427
428 Affected Cortex-A57 parts might report a Stage 2 translation
429 fault as the result of a Stage 1 fault for load crossing a
430 page boundary when there is a permission or device memory
431 alignment fault at Stage 1 and a translation fault at Stage 2.
432
433 The workaround is to verify that the Stage 1 translation
434 doesn't generate a fault before handling the Stage 2 fault.
435 Please note that this does not necessarily enable the workaround,
436 as it depends on the alternative framework, which will only patch
437 the kernel if an affected CPU is detected.
438
439 If unsure, say Y.
440
441config ARM64_ERRATUM_845719
442 bool "Cortex-A53: 845719: a load might read incorrect data"
443 depends on COMPAT
444 default y
445 help
446 This option adds an alternative code sequence to work around ARM
447 erratum 845719 on Cortex-A53 parts up to r0p4.
448
449 When running a compat (AArch32) userspace on an affected Cortex-A53
450 part, a load at EL0 from a virtual address that matches the bottom 32
451 bits of the virtual address used by a recent load at (AArch64) EL1
452 might return incorrect data.
453
454 The workaround is to write the contextidr_el1 register on exception
455 return to a 32-bit task.
456 Please note that this does not necessarily enable the workaround,
457 as it depends on the alternative framework, which will only patch
458 the kernel if an affected CPU is detected.
459
460 If unsure, say Y.
461
462config ARM64_ERRATUM_843419
463 bool "Cortex-A53: 843419: A load or store might access an incorrect address"
464 default y
465 select ARM64_MODULE_PLTS if MODULES
466 help
467 This option links the kernel with '--fix-cortex-a53-843419' and
468 enables PLT support to replace certain ADRP instructions, which can
469 cause subsequent memory accesses to use an incorrect address on
470 Cortex-A53 parts up to r0p4.
471
472 If unsure, say Y.
473
474config ARM64_ERRATUM_1024718
475 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
476 default y
477 help
478 This option adds work around for Arm Cortex-A55 Erratum 1024718.
479
480 Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
481 update of the hardware dirty bit when the DBM/AP bits are updated
482 without a break-before-make. The work around is to disable the usage
483 of hardware DBM locally on the affected cores. CPUs not affected by
484 erratum will continue to use the feature.
485
486 If unsure, say Y.
487
488config ARM64_ERRATUM_1463225
489 bool "Cortex-A76: Software Step might prevent interrupt recognition"
490 default y
491 help
492 This option adds a workaround for Arm Cortex-A76 erratum 1463225.
493
494 On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
495 of a system call instruction (SVC) can prevent recognition of
496 subsequent interrupts when software stepping is disabled in the
497 exception handler of the system call and either kernel debugging
498 is enabled or VHE is in use.
499
500 Work around the erratum by triggering a dummy step exception
501 when handling a system call from a task that is being stepped
502 in a VHE configuration of the kernel.
503
504 If unsure, say Y.
505
506config CAVIUM_ERRATUM_22375
507 bool "Cavium erratum 22375, 24313"
508 default y
509 help
510 Enable workaround for erratum 22375, 24313.
511
512 This implements two gicv3-its errata workarounds for ThunderX. Both
513 with small impact affecting only ITS table allocation.
514
515 erratum 22375: only alloc 8MB table size
516 erratum 24313: ignore memory access type
517
518 The fixes are in ITS initialization and basically ignore memory access
519 type and table size provided by the TYPER and BASER registers.
520
521 If unsure, say Y.
522
523config CAVIUM_ERRATUM_23144
524 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
525 depends on NUMA
526 default y
527 help
528 ITS SYNC command hang for cross node io and collections/cpu mapping.
529
530 If unsure, say Y.
531
532config CAVIUM_ERRATUM_23154
533 bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
534 default y
535 help
536 The gicv3 of ThunderX requires a modified version for
537 reading the IAR status to ensure data synchronization
538 (access to icc_iar1_el1 is not sync'ed before and after).
539
540 If unsure, say Y.
541
542config CAVIUM_ERRATUM_27456
543 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
544 default y
545 help
546 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
547 instructions may cause the icache to become corrupted if it
548 contains data for a non-current ASID. The fix is to
549 invalidate the icache when changing the mm context.
550
551 If unsure, say Y.
552
553config CAVIUM_ERRATUM_30115
554 bool "Cavium erratum 30115: Guest may disable interrupts in host"
555 default y
556 help
557 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
558 1.2, and T83 Pass 1.0, KVM guest execution may disable
559 interrupts in host. Trapping both GICv3 group-0 and group-1
560 accesses sidesteps the issue.
561
562 If unsure, say Y.
563
564config QCOM_FALKOR_ERRATUM_1003
565 bool "Falkor E1003: Incorrect translation due to ASID change"
566 default y
567 help
568 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
569 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
570 in TTBR1_EL1, this situation only occurs in the entry trampoline and
571 then only for entries in the walk cache, since the leaf translation
572 is unchanged. Work around the erratum by invalidating the walk cache
573 entries for the trampoline before entering the kernel proper.
574
575config QCOM_FALKOR_ERRATUM_1009
576 bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
577 default y
578 help
579 On Falkor v1, the CPU may prematurely complete a DSB following a
580 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
581 one more time to fix the issue.
582
583 If unsure, say Y.
584
585config QCOM_QDF2400_ERRATUM_0065
586 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
587 default y
588 help
589 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
590 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
591 been indicated as 16Bytes (0xf), not 8Bytes (0x7).
592
593 If unsure, say Y.
594
595config SOCIONEXT_SYNQUACER_PREITS
596 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
597 default y
598 help
599 Socionext Synquacer SoCs implement a separate h/w block to generate
600 MSI doorbell writes with non-zero values for the device ID.
601
602 If unsure, say Y.
603
604config HISILICON_ERRATUM_161600802
605 bool "Hip07 161600802: Erroneous redistributor VLPI base"
606 default y
607 help
608 The HiSilicon Hip07 SoC usees the wrong redistributor base
609 when issued ITS commands such as VMOVP and VMAPP, and requires
610 a 128kB offset to be applied to the target address in this commands.
611
612 If unsure, say Y.
613
614config QCOM_FALKOR_ERRATUM_E1041
615 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
616 default y
617 help
618 Falkor CPU may speculatively fetch instructions from an improper
619 memory location when MMU translation is changed from SCTLR_ELn[M]=1
620 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
621
622 If unsure, say Y.
623
624endmenu
625
626
627choice
628 prompt "Page size"
629 default ARM64_4K_PAGES
630 help
631 Page size (translation granule) configuration.
632
633config ARM64_4K_PAGES
634 bool "4KB"
635 help
636 This feature enables 4KB pages support.
637
638config ARM64_16K_PAGES
639 bool "16KB"
640 help
641 The system will use 16KB pages support. AArch32 emulation
642 requires applications compiled with 16K (or a multiple of 16K)
643 aligned segments.
644
645config ARM64_64K_PAGES
646 bool "64KB"
647 help
648 This feature enables 64KB pages support (4KB by default)
649 allowing only two levels of page tables and faster TLB
650 look-up. AArch32 emulation requires applications compiled
651 with 64K aligned segments.
652
653endchoice
654
655choice
656 prompt "Virtual address space size"
657 default ARM64_VA_BITS_39 if ARM64_4K_PAGES
658 default ARM64_VA_BITS_47 if ARM64_16K_PAGES
659 default ARM64_VA_BITS_42 if ARM64_64K_PAGES
660 help
661 Allows choosing one of multiple possible virtual address
662 space sizes. The level of translation table is determined by
663 a combination of page size and virtual address space size.
664
665config ARM64_VA_BITS_36
666 bool "36-bit" if EXPERT
667 depends on ARM64_16K_PAGES
668
669config ARM64_VA_BITS_39
670 bool "39-bit"
671 depends on ARM64_4K_PAGES
672
673config ARM64_VA_BITS_42
674 bool "42-bit"
675 depends on ARM64_64K_PAGES
676
677config ARM64_VA_BITS_47
678 bool "47-bit"
679 depends on ARM64_16K_PAGES
680
681config ARM64_VA_BITS_48
682 bool "48-bit"
683
684endchoice
685
686config ARM64_VA_BITS
687 int
688 default 36 if ARM64_VA_BITS_36
689 default 39 if ARM64_VA_BITS_39
690 default 42 if ARM64_VA_BITS_42
691 default 47 if ARM64_VA_BITS_47
692 default 48 if ARM64_VA_BITS_48
693
694choice
695 prompt "Physical address space size"
696 default ARM64_PA_BITS_48
697 help
698 Choose the maximum physical address range that the kernel will
699 support.
700
701config ARM64_PA_BITS_48
702 bool "48-bit"
703
704config ARM64_PA_BITS_52
705 bool "52-bit (ARMv8.2)"
706 depends on ARM64_64K_PAGES
707 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
708 help
709 Enable support for a 52-bit physical address space, introduced as
710 part of the ARMv8.2-LPA extension.
711
712 With this enabled, the kernel will also continue to work on CPUs that
713 do not support ARMv8.2-LPA, but with some added memory overhead (and
714 minor performance overhead).
715
716endchoice
717
718config ARM64_PA_BITS
719 int
720 default 48 if ARM64_PA_BITS_48
721 default 52 if ARM64_PA_BITS_52
722
723config CPU_BIG_ENDIAN
724 bool "Build big-endian kernel"
725 help
726 Say Y if you plan on running a kernel in big-endian mode.
727
728config SCHED_MC
729 bool "Multi-core scheduler support"
730 help
731 Multi-core scheduler support improves the CPU scheduler's decision
732 making when dealing with multi-core CPU chips at a cost of slightly
733 increased overhead in some places. If unsure say N here.
734
735config SCHED_SMT
736 bool "SMT scheduler support"
737 help
738 Improves the CPU scheduler's decision making when dealing with
739 MultiThreading at a cost of slightly increased overhead in some
740 places. If unsure say N here.
741
742config NR_CPUS
743 int "Maximum number of CPUs (2-4096)"
744 range 2 4096
745 # These have to remain sorted largest to smallest
746 default "64"
747
748config HOTPLUG_CPU
749 bool "Support for hot-pluggable CPUs"
750 select GENERIC_IRQ_MIGRATION
751 help
752 Say Y here to experiment with turning CPUs off and on. CPUs
753 can be controlled through /sys/devices/system/cpu.
754
755# Common NUMA Features
756config NUMA
757 bool "Numa Memory Allocation and Scheduler Support"
758 select ACPI_NUMA if ACPI
759 select OF_NUMA
760 help
761 Enable NUMA (Non Uniform Memory Access) support.
762
763 The kernel will try to allocate memory used by a CPU on the
764 local memory of the CPU and add some more
765 NUMA awareness to the kernel.
766
767config NODES_SHIFT
768 int "Maximum NUMA Nodes (as a power of 2)"
769 range 1 10
770 default "2"
771 depends on NEED_MULTIPLE_NODES
772 help
773 Specify the maximum number of NUMA Nodes available on the target
774 system. Increases memory reserved to accommodate various tables.
775
776config USE_PERCPU_NUMA_NODE_ID
777 def_bool y
778 depends on NUMA
779
780config HAVE_SETUP_PER_CPU_AREA
781 def_bool y
782 depends on NUMA
783
784config NEED_PER_CPU_EMBED_FIRST_CHUNK
785 def_bool y
786 depends on NUMA
787
788config HOLES_IN_ZONE
789 def_bool y
790
791source kernel/Kconfig.hz
792
793config ARCH_SUPPORTS_DEBUG_PAGEALLOC
794 def_bool y
795
796config ARCH_HAS_HOLES_MEMORYMODEL
797 def_bool y if SPARSEMEM
798
799config ARCH_SPARSEMEM_ENABLE
800 def_bool y
801 select SPARSEMEM_VMEMMAP_ENABLE
802
803config ARCH_SPARSEMEM_DEFAULT
804 def_bool ARCH_SPARSEMEM_ENABLE
805
806config ARCH_SELECT_MEMORY_MODEL
807 def_bool ARCH_SPARSEMEM_ENABLE
808
809config ARCH_FLATMEM_ENABLE
810 def_bool !NUMA
811
812config HAVE_ARCH_PFN_VALID
813 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
814
815config HW_PERF_EVENTS
816 def_bool y
817 depends on ARM_PMU
818
819config SYS_SUPPORTS_HUGETLBFS
820 def_bool y
821
822config ARCH_WANT_HUGE_PMD_SHARE
823 def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
824
825config ARCH_HAS_CACHE_LINE_SIZE
826 def_bool y
827
828
829# Supported by clang >= 7.0
830config CC_HAVE_SHADOW_CALL_STACK
831 def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
832
833config SECCOMP
834 bool "Enable seccomp to safely compute untrusted bytecode"
835 ---help---
836 This kernel feature is useful for number crunching applications
837 that may need to compute untrusted bytecode during their
838 execution. By using pipes or other transports made available to
839 the process as file descriptors supporting the read/write
840 syscalls, it's possible to isolate those applications in
841 their own address space using seccomp. Once seccomp is
842 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
843 and the task is only allowed to execute a few safe syscalls
844 defined by each seccomp mode.
845
846config PARAVIRT
847 bool "Enable paravirtualization code"
848 help
849 This changes the kernel so it can modify itself when it is run
850 under a hypervisor, potentially improving performance significantly
851 over full virtualization.
852
853config PARAVIRT_TIME_ACCOUNTING
854 bool "Paravirtual steal time accounting"
855 select PARAVIRT
856 default n
857 help
858 Select this option to enable fine granularity task steal time
859 accounting. Time spent executing other tasks in parallel with
860 the current vCPU is discounted from the vCPU power. To account for
861 that, there can be a small performance impact.
862
863 If in doubt, say N here.
864
865config KEXEC
866 depends on PM_SLEEP_SMP
867 select KEXEC_CORE
868 bool "kexec system call"
869 ---help---
870 kexec is a system call that implements the ability to shutdown your
871 current kernel, and to start another kernel. It is like a reboot
872 but it is independent of the system firmware. And like a reboot
873 you can start any kernel with it, not just Linux.
874
875config CRASH_DUMP
876 bool "Build kdump crash kernel"
877 help
878 Generate crash dump after being started by kexec. This should
879 be normally only set in special crash dump kernels which are
880 loaded in the main kernel with kexec-tools into a specially
881 reserved region and then later executed after a crash by
882 kdump/kexec.
883
884 For more details see Documentation/kdump/kdump.txt
885
886config XEN_DOM0
887 def_bool y
888 depends on XEN
889
890config XEN
891 bool "Xen guest support on ARM64"
892 depends on ARM64 && OF
893 select SWIOTLB_XEN
894 select PARAVIRT
895 help
896 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
897
898config FORCE_MAX_ZONEORDER
899 int
900 default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
901 default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
902 default "11"
903 help
904 The kernel memory allocator divides physically contiguous memory
905 blocks into "zones", where each zone is a power of two number of
906 pages. This option selects the largest power of two that the kernel
907 keeps in the memory allocator. If you need to allocate very large
908 blocks of physically contiguous memory, then you may need to
909 increase this value.
910
911 This config option is actually maximum order plus one. For example,
912 a value of 11 means that the largest free memory block is 2^10 pages.
913
914 We make sure that we can allocate upto a HugePage size for each configuration.
915 Hence we have :
916 MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
917
918 However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
919 4M allocations matching the default size used by generic code.
920
921config UNMAP_KERNEL_AT_EL0
922 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
923 default y
924 help
925 Speculation attacks against some high-performance processors can
926 be used to bypass MMU permission checks and leak kernel data to
927 userspace. This can be defended against by unmapping the kernel
928 when running in userspace, mapping it back in on exception entry
929 via a trampoline page in the vector table.
930
931 If unsure, say Y.
932
933config HARDEN_BRANCH_PREDICTOR
934 bool "Harden the branch predictor against aliasing attacks" if EXPERT
935 default y
936 help
937 Speculation attacks against some high-performance processors rely on
938 being able to manipulate the branch predictor for a victim context by
939 executing aliasing branches in the attacker context. Such attacks
940 can be partially mitigated against by clearing internal branch
941 predictor state and limiting the prediction logic in some situations.
942
943 This config option will take CPU-specific actions to harden the
944 branch predictor against aliasing attacks and may rely on specific
945 instruction sequences or control bits being set by the system
946 firmware.
947
948 If unsure, say Y.
949
950config HARDEN_EL2_VECTORS
951 bool "Harden EL2 vector mapping against system register leak" if EXPERT
952 default y
953 help
954 Speculation attacks against some high-performance processors can
955 be used to leak privileged information such as the vector base
956 register, resulting in a potential defeat of the EL2 layout
957 randomization.
958
959 This config option will map the vectors to a fixed location,
960 independent of the EL2 code mapping, so that revealing VBAR_EL2
961 to an attacker does not give away any extra information. This
962 only gets enabled on affected CPUs.
963
964 If unsure, say Y.
965
966config ARM64_SSBD
967 bool "Speculative Store Bypass Disable" if EXPERT
968 default y
969 help
970 This enables mitigation of the bypassing of previous stores
971 by speculative loads.
972
973 If unsure, say Y.
974
975config ARM64_TAGGED_ADDR_ABI
976 bool "Enable the tagged user addresses syscall ABI"
977 default y
978 help
979 When this option is enabled, user applications can opt in to a
980 relaxed ABI via prctl() allowing tagged addresses to be passed
981 to system calls as pointer arguments. For details, see
982 Documentation/arm64/tagged-address-abi.rst.
983
984menuconfig ARMV8_DEPRECATED
985 bool "Emulate deprecated/obsolete ARMv8 instructions"
986 depends on COMPAT
987 depends on SYSCTL
988 help
989 Legacy software support may require certain instructions
990 that have been deprecated or obsoleted in the architecture.
991
992 Enable this config to enable selective emulation of these
993 features.
994
995 If unsure, say Y
996
997if ARMV8_DEPRECATED
998
999config SWP_EMULATION
1000 bool "Emulate SWP/SWPB instructions"
1001 help
1002 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1003 they are always undefined. Say Y here to enable software
1004 emulation of these instructions for userspace using LDXR/STXR.
1005
1006 In some older versions of glibc [<=2.8] SWP is used during futex
1007 trylock() operations with the assumption that the code will not
1008 be preempted. This invalid assumption may be more likely to fail
1009 with SWP emulation enabled, leading to deadlock of the user
1010 application.
1011
1012 NOTE: when accessing uncached shared regions, LDXR/STXR rely
1013 on an external transaction monitoring block called a global
1014 monitor to maintain update atomicity. If your system does not
1015 implement a global monitor, this option can cause programs that
1016 perform SWP operations to uncached memory to deadlock.
1017
1018 If unsure, say Y
1019
1020config CP15_BARRIER_EMULATION
1021 bool "Emulate CP15 Barrier instructions"
1022 help
1023 The CP15 barrier instructions - CP15ISB, CP15DSB, and
1024 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1025 strongly recommended to use the ISB, DSB, and DMB
1026 instructions instead.
1027
1028 Say Y here to enable software emulation of these
1029 instructions for AArch32 userspace code. When this option is
1030 enabled, CP15 barrier usage is traced which can help
1031 identify software that needs updating.
1032
1033 If unsure, say Y
1034
1035config SETEND_EMULATION
1036 bool "Emulate SETEND instruction"
1037 help
1038 The SETEND instruction alters the data-endianness of the
1039 AArch32 EL0, and is deprecated in ARMv8.
1040
1041 Say Y here to enable software emulation of the instruction
1042 for AArch32 userspace code.
1043
1044 Note: All the cpus on the system must have mixed endian support at EL0
1045 for this feature to be enabled. If a new CPU - which doesn't support mixed
1046 endian - is hotplugged in after this feature has been enabled, there could
1047 be unexpected results in the applications.
1048
1049 If unsure, say Y
1050endif
1051
1052config ARM64_SW_TTBR0_PAN
1053 bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1054 help
1055 Enabling this option prevents the kernel from accessing
1056 user-space memory directly by pointing TTBR0_EL1 to a reserved
1057 zeroed area and reserved ASID. The user access routines
1058 restore the valid TTBR0_EL1 temporarily.
1059
1060menu "ARMv8.1 architectural features"
1061
1062config ARM64_HW_AFDBM
1063 bool "Support for hardware updates of the Access and Dirty page flags"
1064 default y
1065 help
1066 The ARMv8.1 architecture extensions introduce support for
1067 hardware updates of the access and dirty information in page
1068 table entries. When enabled in TCR_EL1 (HA and HD bits) on
1069 capable processors, accesses to pages with PTE_AF cleared will
1070 set this bit instead of raising an access flag fault.
1071 Similarly, writes to read-only pages with the DBM bit set will
1072 clear the read-only bit (AP[2]) instead of raising a
1073 permission fault.
1074
1075 Kernels built with this configuration option enabled continue
1076 to work on pre-ARMv8.1 hardware and the performance impact is
1077 minimal. If unsure, say Y.
1078
1079config ARM64_PAN
1080 bool "Enable support for Privileged Access Never (PAN)"
1081 default y
1082 help
1083 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1084 prevents the kernel or hypervisor from accessing user-space (EL0)
1085 memory directly.
1086
1087 Choosing this option will cause any unprotected (not using
1088 copy_to_user et al) memory access to fail with a permission fault.
1089
1090 The feature is detected at runtime, and will remain as a 'nop'
1091 instruction if the cpu does not implement the feature.
1092
1093config ARM64_LSE_ATOMICS
1094 bool "Atomic instructions"
1095 default y
1096 help
1097 As part of the Large System Extensions, ARMv8.1 introduces new
1098 atomic instructions that are designed specifically to scale in
1099 very large systems.
1100
1101 Say Y here to make use of these instructions for the in-kernel
1102 atomic routines. This incurs a small overhead on CPUs that do
1103 not support these instructions and requires the kernel to be
1104 built with binutils >= 2.25 in order for the new instructions
1105 to be used.
1106
1107config ARM64_VHE
1108 bool "Enable support for Virtualization Host Extensions (VHE)"
1109 default y
1110 help
1111 Virtualization Host Extensions (VHE) allow the kernel to run
1112 directly at EL2 (instead of EL1) on processors that support
1113 it. This leads to better performance for KVM, as they reduce
1114 the cost of the world switch.
1115
1116 Selecting this option allows the VHE feature to be detected
1117 at runtime, and does not affect processors that do not
1118 implement this feature.
1119
1120endmenu
1121
1122menu "ARMv8.2 architectural features"
1123
1124config ARM64_UAO
1125 bool "Enable support for User Access Override (UAO)"
1126 default y
1127 help
1128 User Access Override (UAO; part of the ARMv8.2 Extensions)
1129 causes the 'unprivileged' variant of the load/store instructions to
1130 be overridden to be privileged.
1131
1132 This option changes get_user() and friends to use the 'unprivileged'
1133 variant of the load/store instructions. This ensures that user-space
1134 really did have access to the supplied memory. When addr_limit is
1135 set to kernel memory the UAO bit will be set, allowing privileged
1136 access to kernel memory.
1137
1138 Choosing this option will cause copy_to_user() et al to use user-space
1139 memory permissions.
1140
1141 The feature is detected at runtime, the kernel will use the
1142 regular load/store instructions if the cpu does not implement the
1143 feature.
1144
1145config ARM64_PMEM
1146 bool "Enable support for persistent memory"
1147 select ARCH_HAS_PMEM_API
1148 select ARCH_HAS_UACCESS_FLUSHCACHE
1149 help
1150 Say Y to enable support for the persistent memory API based on the
1151 ARMv8.2 DCPoP feature.
1152
1153 The feature is detected at runtime, and the kernel will use DC CVAC
1154 operations if DC CVAP is not supported (following the behaviour of
1155 DC CVAP itself if the system does not define a point of persistence).
1156
1157config ARM64_RAS_EXTN
1158 bool "Enable support for RAS CPU Extensions"
1159 default y
1160 help
1161 CPUs that support the Reliability, Availability and Serviceability
1162 (RAS) Extensions, part of ARMv8.2 are able to track faults and
1163 errors, classify them and report them to software.
1164
1165 On CPUs with these extensions system software can use additional
1166 barriers to determine if faults are pending and read the
1167 classification from a new set of registers.
1168
1169 Selecting this feature will allow the kernel to use these barriers
1170 and access the new registers if the system supports the extension.
1171 Platform RAS features may additionally depend on firmware support.
1172
1173endmenu
1174
1175config ARM64_SVE
1176 bool "ARM Scalable Vector Extension support"
1177 default y
1178 depends on !KVM || ARM64_VHE
1179 help
1180 The Scalable Vector Extension (SVE) is an extension to the AArch64
1181 execution state which complements and extends the SIMD functionality
1182 of the base architecture to support much larger vectors and to enable
1183 additional vectorisation opportunities.
1184
1185 To enable use of this extension on CPUs that implement it, say Y.
1186
1187 Note that for architectural reasons, firmware _must_ implement SVE
1188 support when running on SVE capable hardware. The required support
1189 is present in:
1190
1191 * version 1.5 and later of the ARM Trusted Firmware
1192 * the AArch64 boot wrapper since commit 5e1261e08abf
1193 ("bootwrapper: SVE: Enable SVE for EL2 and below").
1194
1195 For other firmware implementations, consult the firmware documentation
1196 or vendor.
1197
1198 If you need the kernel to boot on SVE-capable hardware with broken
1199 firmware, you may need to say N here until you get your firmware
1200 fixed. Otherwise, you may experience firmware panics or lockups when
1201 booting the kernel. If unsure and you are not observing these
1202 symptoms, you should assume that it is safe to say Y.
1203
1204 CPUs that support SVE are architecturally required to support the
1205 Virtualization Host Extensions (VHE), so the kernel makes no
1206 provision for supporting SVE alongside KVM without VHE enabled.
1207 Thus, you will need to enable CONFIG_ARM64_VHE if you want to support
1208 KVM in the same kernel image.
1209
1210config ARM64_MODULE_PLTS
1211 bool
1212 select HAVE_MOD_ARCH_SPECIFIC
1213
1214config RELOCATABLE
1215 bool
1216 select ARCH_HAS_RELR
1217 help
1218 This builds the kernel as a Position Independent Executable (PIE),
1219 which retains all relocation metadata required to relocate the
1220 kernel binary at runtime to a different virtual address than the
1221 address it was linked at.
1222 Since AArch64 uses the RELA relocation format, this requires a
1223 relocation pass at runtime even if the kernel is loaded at the
1224 same address it was linked at.
1225
1226config RANDOMIZE_BASE
1227 bool "Randomize the address of the kernel image"
1228 select ARM64_MODULE_PLTS if MODULES
1229 select RELOCATABLE
1230 help
1231 Randomizes the virtual address at which the kernel image is
1232 loaded, as a security feature that deters exploit attempts
1233 relying on knowledge of the location of kernel internals.
1234
1235 It is the bootloader's job to provide entropy, by passing a
1236 random u64 value in /chosen/kaslr-seed at kernel entry.
1237
1238 When booting via the UEFI stub, it will invoke the firmware's
1239 EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1240 to the kernel proper. In addition, it will randomise the physical
1241 location of the kernel Image as well.
1242
1243 If unsure, say N.
1244
1245config RANDOMIZE_MODULE_REGION_FULL
1246 bool "Randomize the module region over a 4 GB range"
1247 depends on RANDOMIZE_BASE
1248 default y
1249 help
1250 Randomizes the location of the module region inside a 4 GB window
1251 covering the core kernel. This way, it is less likely for modules
1252 to leak information about the location of core kernel data structures
1253 but it does imply that function calls between modules and the core
1254 kernel will need to be resolved via veneers in the module PLT.
1255
1256 When this option is not set, the module region will be randomized over
1257 a limited range that contains the [_stext, _etext] interval of the
1258 core kernel, so branch relocations are always in range.
1259
1260endmenu
1261
1262menu "Boot options"
1263
1264config ARM64_ACPI_PARKING_PROTOCOL
1265 bool "Enable support for the ARM64 ACPI parking protocol"
1266 depends on ACPI
1267 help
1268 Enable support for the ARM64 ACPI parking protocol. If disabled
1269 the kernel will not allow booting through the ARM64 ACPI parking
1270 protocol even if the corresponding data is present in the ACPI
1271 MADT table.
1272
1273config CMDLINE
1274 string "Default kernel command string"
1275 default ""
1276 help
1277 Provide a set of default command-line options at build time by
1278 entering them here. As a minimum, you should specify the the
1279 root device (e.g. root=/dev/nfs).
1280
1281choice
1282 prompt "Kernel command line type" if CMDLINE != ""
1283 default CMDLINE_FROM_BOOTLOADER
1284
1285config CMDLINE_FROM_BOOTLOADER
1286 bool "Use bootloader kernel arguments if available"
1287 help
1288 Uses the command-line options passed by the boot loader. If
1289 the boot loader doesn't provide any, the default kernel command
1290 string provided in CMDLINE will be used.
1291
1292config CMDLINE_EXTEND
1293 bool "Extend bootloader kernel arguments"
1294 help
1295 The command-line arguments provided by the boot loader will be
1296 appended to the default kernel command string.
1297
1298config CMDLINE_FORCE
1299 bool "Always use the default kernel command string"
1300 help
1301 Always use the default kernel command string, even if the boot
1302 loader passes other arguments to the kernel.
1303 This is useful if you cannot or don't want to change the
1304 command-line options your boot loader passes to the kernel.
1305endchoice
1306
1307config EFI_STUB
1308 bool
1309
1310config EFI
1311 bool "UEFI runtime support"
1312 depends on OF && !CPU_BIG_ENDIAN
1313 depends on KERNEL_MODE_NEON
1314 select ARCH_SUPPORTS_ACPI
1315 select LIBFDT
1316 select UCS2_STRING
1317 select EFI_PARAMS_FROM_FDT
1318 select EFI_RUNTIME_WRAPPERS
1319 select EFI_STUB
1320 select EFI_ARMSTUB
1321 default y
1322 help
1323 This option provides support for runtime services provided
1324 by UEFI firmware (such as non-volatile variables, realtime
1325 clock, and platform reset). A UEFI stub is also provided to
1326 allow the kernel to be booted as an EFI application. This
1327 is only useful on systems that have UEFI firmware.
1328
1329config DMI
1330 bool "Enable support for SMBIOS (DMI) tables"
1331 depends on EFI
1332 default y
1333 help
1334 This enables SMBIOS/DMI feature for systems.
1335
1336 This option is only useful on systems that have UEFI firmware.
1337 However, even with this option, the resultant kernel should
1338 continue to boot on existing non-UEFI platforms.
1339
1340endmenu
1341
1342config COMPAT
1343 bool "Kernel support for 32-bit EL0"
1344 depends on ARM64_4K_PAGES || EXPERT
1345 select COMPAT_BINFMT_ELF if BINFMT_ELF
1346 select HAVE_UID16
1347 select OLD_SIGSUSPEND3
1348 select COMPAT_OLD_SIGACTION
1349 help
1350 This option enables support for a 32-bit EL0 running under a 64-bit
1351 kernel at EL1. AArch32-specific components such as system calls,
1352 the user helper functions, VFP support and the ptrace interface are
1353 handled appropriately by the kernel.
1354
1355 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1356 that you will only be able to execute AArch32 binaries that were compiled
1357 with page size aligned segments.
1358
1359 If you want to execute 32-bit userspace applications, say Y.
1360
1361config SYSVIPC_COMPAT
1362 def_bool y
1363 depends on COMPAT && SYSVIPC
1364
1365menu "Power management options"
1366
1367source "kernel/power/Kconfig"
1368
1369config ARCH_HIBERNATION_POSSIBLE
1370 def_bool y
1371 depends on CPU_PM
1372
1373config ARCH_HIBERNATION_HEADER
1374 def_bool y
1375 depends on HIBERNATION
1376
1377config ARCH_SUSPEND_POSSIBLE
1378 def_bool y
1379
1380endmenu
1381
1382menu "CPU Power Management"
1383
1384source "drivers/cpuidle/Kconfig"
1385
1386source "drivers/cpufreq/Kconfig"
1387
1388endmenu
1389
1390source "drivers/firmware/Kconfig"
1391
1392source "drivers/acpi/Kconfig"
1393
1394source "arch/arm64/kvm/Kconfig"
1395
1396if CRYPTO
1397source "arch/arm64/crypto/Kconfig"
1398endif