xref: /openbmc/linux/arch/arm64/Kconfig (revision 74ce1896)
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
9	select ACPI_SPCR_TABLE if ACPI
10	select ARCH_CLOCKSOURCE_DATA
11	select ARCH_HAS_DEBUG_VIRTUAL
12	select ARCH_HAS_DEVMEM_IS_ALLOWED
13	select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
14	select ARCH_HAS_ELF_RANDOMIZE
15	select ARCH_HAS_FORTIFY_SOURCE
16	select ARCH_HAS_GCOV_PROFILE_ALL
17	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
18	select ARCH_HAS_KCOV
19	select ARCH_HAS_SET_MEMORY
20	select ARCH_HAS_SG_CHAIN
21	select ARCH_HAS_STRICT_KERNEL_RWX
22	select ARCH_HAS_STRICT_MODULE_RWX
23	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
24	select ARCH_HAVE_NMI_SAFE_CMPXCHG if ACPI_APEI_SEA
25	select ARCH_USE_CMPXCHG_LOCKREF
26	select ARCH_SUPPORTS_MEMORY_FAILURE
27	select ARCH_SUPPORTS_ATOMIC_RMW
28	select ARCH_SUPPORTS_NUMA_BALANCING
29	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
30	select ARCH_WANT_FRAME_POINTERS
31	select ARCH_HAS_UBSAN_SANITIZE_ALL
32	select ARM_AMBA
33	select ARM_ARCH_TIMER
34	select ARM_GIC
35	select AUDIT_ARCH_COMPAT_GENERIC
36	select ARM_GIC_V2M if PCI
37	select ARM_GIC_V3
38	select ARM_GIC_V3_ITS if PCI
39	select ARM_PSCI_FW
40	select BUILDTIME_EXTABLE_SORT
41	select CLONE_BACKWARDS
42	select COMMON_CLK
43	select CPU_PM if (SUSPEND || CPU_IDLE)
44	select DCACHE_WORD_ACCESS
45	select EDAC_SUPPORT
46	select FRAME_POINTER
47	select GENERIC_ALLOCATOR
48	select GENERIC_ARCH_TOPOLOGY
49	select GENERIC_CLOCKEVENTS
50	select GENERIC_CLOCKEVENTS_BROADCAST
51	select GENERIC_CPU_AUTOPROBE
52	select GENERIC_EARLY_IOREMAP
53	select GENERIC_IDLE_POLL_SETUP
54	select GENERIC_IRQ_PROBE
55	select GENERIC_IRQ_SHOW
56	select GENERIC_IRQ_SHOW_LEVEL
57	select GENERIC_PCI_IOMAP
58	select GENERIC_SCHED_CLOCK
59	select GENERIC_SMP_IDLE_THREAD
60	select GENERIC_STRNCPY_FROM_USER
61	select GENERIC_STRNLEN_USER
62	select GENERIC_TIME_VSYSCALL
63	select HANDLE_DOMAIN_IRQ
64	select HARDIRQS_SW_RESEND
65	select HAVE_ACPI_APEI if (ACPI && EFI)
66	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
67	select HAVE_ARCH_AUDITSYSCALL
68	select HAVE_ARCH_BITREVERSE
69	select HAVE_ARCH_HUGE_VMAP
70	select HAVE_ARCH_JUMP_LABEL
71	select HAVE_ARCH_KASAN if SPARSEMEM_VMEMMAP && !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
72	select HAVE_ARCH_KGDB
73	select HAVE_ARCH_MMAP_RND_BITS
74	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
75	select HAVE_ARCH_SECCOMP_FILTER
76	select HAVE_ARCH_TRACEHOOK
77	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
78	select HAVE_ARCH_VMAP_STACK
79	select HAVE_ARM_SMCCC
80	select HAVE_EBPF_JIT
81	select HAVE_C_RECORDMCOUNT
82	select HAVE_CC_STACKPROTECTOR
83	select HAVE_CMPXCHG_DOUBLE
84	select HAVE_CMPXCHG_LOCAL
85	select HAVE_CONTEXT_TRACKING
86	select HAVE_DEBUG_BUGVERBOSE
87	select HAVE_DEBUG_KMEMLEAK
88	select HAVE_DMA_API_DEBUG
89	select HAVE_DMA_CONTIGUOUS
90	select HAVE_DYNAMIC_FTRACE
91	select HAVE_EFFICIENT_UNALIGNED_ACCESS
92	select HAVE_FTRACE_MCOUNT_RECORD
93	select HAVE_FUNCTION_TRACER
94	select HAVE_FUNCTION_GRAPH_TRACER
95	select HAVE_GCC_PLUGINS
96	select HAVE_GENERIC_DMA_COHERENT
97	select HAVE_HW_BREAKPOINT if PERF_EVENTS
98	select HAVE_IRQ_TIME_ACCOUNTING
99	select HAVE_MEMBLOCK
100	select HAVE_MEMBLOCK_NODE_MAP if NUMA
101	select HAVE_NMI if ACPI_APEI_SEA
102	select HAVE_PATA_PLATFORM
103	select HAVE_PERF_EVENTS
104	select HAVE_PERF_REGS
105	select HAVE_PERF_USER_STACK_DUMP
106	select HAVE_REGS_AND_STACK_ACCESS_API
107	select HAVE_RCU_TABLE_FREE
108	select HAVE_SYSCALL_TRACEPOINTS
109	select HAVE_KPROBES
110	select HAVE_KRETPROBES
111	select IOMMU_DMA if IOMMU_SUPPORT
112	select IRQ_DOMAIN
113	select IRQ_FORCED_THREADING
114	select MODULES_USE_ELF_RELA
115	select NO_BOOTMEM
116	select OF
117	select OF_EARLY_FLATTREE
118	select OF_RESERVED_MEM
119	select PCI_ECAM if ACPI
120	select POWER_RESET
121	select POWER_SUPPLY
122	select SPARSE_IRQ
123	select SYSCTL_EXCEPTION_TRACE
124	select THREAD_INFO_IN_TASK
125	help
126	  ARM 64-bit (AArch64) Linux support.
127
128config 64BIT
129	def_bool y
130
131config ARCH_PHYS_ADDR_T_64BIT
132	def_bool y
133
134config MMU
135	def_bool y
136
137config ARM64_PAGE_SHIFT
138	int
139	default 16 if ARM64_64K_PAGES
140	default 14 if ARM64_16K_PAGES
141	default 12
142
143config ARM64_CONT_SHIFT
144	int
145	default 5 if ARM64_64K_PAGES
146	default 7 if ARM64_16K_PAGES
147	default 4
148
149config ARCH_MMAP_RND_BITS_MIN
150       default 14 if ARM64_64K_PAGES
151       default 16 if ARM64_16K_PAGES
152       default 18
153
154# max bits determined by the following formula:
155#  VA_BITS - PAGE_SHIFT - 3
156config ARCH_MMAP_RND_BITS_MAX
157       default 19 if ARM64_VA_BITS=36
158       default 24 if ARM64_VA_BITS=39
159       default 27 if ARM64_VA_BITS=42
160       default 30 if ARM64_VA_BITS=47
161       default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
162       default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
163       default 33 if ARM64_VA_BITS=48
164       default 14 if ARM64_64K_PAGES
165       default 16 if ARM64_16K_PAGES
166       default 18
167
168config ARCH_MMAP_RND_COMPAT_BITS_MIN
169       default 7 if ARM64_64K_PAGES
170       default 9 if ARM64_16K_PAGES
171       default 11
172
173config ARCH_MMAP_RND_COMPAT_BITS_MAX
174       default 16
175
176config NO_IOPORT_MAP
177	def_bool y if !PCI
178
179config STACKTRACE_SUPPORT
180	def_bool y
181
182config ILLEGAL_POINTER_VALUE
183	hex
184	default 0xdead000000000000
185
186config LOCKDEP_SUPPORT
187	def_bool y
188
189config TRACE_IRQFLAGS_SUPPORT
190	def_bool y
191
192config RWSEM_XCHGADD_ALGORITHM
193	def_bool y
194
195config GENERIC_BUG
196	def_bool y
197	depends on BUG
198
199config GENERIC_BUG_RELATIVE_POINTERS
200	def_bool y
201	depends on GENERIC_BUG
202
203config GENERIC_HWEIGHT
204	def_bool y
205
206config GENERIC_CSUM
207        def_bool y
208
209config GENERIC_CALIBRATE_DELAY
210	def_bool y
211
212config ZONE_DMA
213	def_bool y
214
215config HAVE_GENERIC_GUP
216	def_bool y
217
218config ARCH_DMA_ADDR_T_64BIT
219	def_bool y
220
221config NEED_DMA_MAP_STATE
222	def_bool y
223
224config NEED_SG_DMA_LENGTH
225	def_bool y
226
227config SMP
228	def_bool y
229
230config SWIOTLB
231	def_bool y
232
233config IOMMU_HELPER
234	def_bool SWIOTLB
235
236config KERNEL_MODE_NEON
237	def_bool y
238
239config FIX_EARLYCON_MEM
240	def_bool y
241
242config PGTABLE_LEVELS
243	int
244	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
245	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
246	default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48
247	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
248	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
249	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
250
251config ARCH_SUPPORTS_UPROBES
252	def_bool y
253
254config ARCH_PROC_KCORE_TEXT
255	def_bool y
256
257source "init/Kconfig"
258
259source "kernel/Kconfig.freezer"
260
261source "arch/arm64/Kconfig.platforms"
262
263menu "Bus support"
264
265config PCI
266	bool "PCI support"
267	help
268	  This feature enables support for PCI bus system. If you say Y
269	  here, the kernel will include drivers and infrastructure code
270	  to support PCI bus devices.
271
272config PCI_DOMAINS
273	def_bool PCI
274
275config PCI_DOMAINS_GENERIC
276	def_bool PCI
277
278config PCI_SYSCALL
279	def_bool PCI
280
281source "drivers/pci/Kconfig"
282
283endmenu
284
285menu "Kernel Features"
286
287menu "ARM errata workarounds via the alternatives framework"
288
289config ARM64_ERRATUM_826319
290	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
291	default y
292	help
293	  This option adds an alternative code sequence to work around ARM
294	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
295	  AXI master interface and an L2 cache.
296
297	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
298	  and is unable to accept a certain write via this interface, it will
299	  not progress on read data presented on the read data channel and the
300	  system can deadlock.
301
302	  The workaround promotes data cache clean instructions to
303	  data cache clean-and-invalidate.
304	  Please note that this does not necessarily enable the workaround,
305	  as it depends on the alternative framework, which will only patch
306	  the kernel if an affected CPU is detected.
307
308	  If unsure, say Y.
309
310config ARM64_ERRATUM_827319
311	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
312	default y
313	help
314	  This option adds an alternative code sequence to work around ARM
315	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
316	  master interface and an L2 cache.
317
318	  Under certain conditions this erratum can cause a clean line eviction
319	  to occur at the same time as another transaction to the same address
320	  on the AMBA 5 CHI interface, which can cause data corruption if the
321	  interconnect reorders the two transactions.
322
323	  The workaround promotes data cache clean instructions to
324	  data cache clean-and-invalidate.
325	  Please note that this does not necessarily enable the workaround,
326	  as it depends on the alternative framework, which will only patch
327	  the kernel if an affected CPU is detected.
328
329	  If unsure, say Y.
330
331config ARM64_ERRATUM_824069
332	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
333	default y
334	help
335	  This option adds an alternative code sequence to work around ARM
336	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
337	  to a coherent interconnect.
338
339	  If a Cortex-A53 processor is executing a store or prefetch for
340	  write instruction at the same time as a processor in another
341	  cluster is executing a cache maintenance operation to the same
342	  address, then this erratum might cause a clean cache line to be
343	  incorrectly marked as dirty.
344
345	  The workaround promotes data cache clean instructions to
346	  data cache clean-and-invalidate.
347	  Please note that this option does not necessarily enable the
348	  workaround, as it depends on the alternative framework, which will
349	  only patch the kernel if an affected CPU is detected.
350
351	  If unsure, say Y.
352
353config ARM64_ERRATUM_819472
354	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
355	default y
356	help
357	  This option adds an alternative code sequence to work around ARM
358	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
359	  present when it is connected to a coherent interconnect.
360
361	  If the processor is executing a load and store exclusive sequence at
362	  the same time as a processor in another cluster is executing a cache
363	  maintenance operation to the same address, then this erratum might
364	  cause data corruption.
365
366	  The workaround promotes data cache clean instructions to
367	  data cache clean-and-invalidate.
368	  Please note that this does not necessarily enable the workaround,
369	  as it depends on the alternative framework, which will only patch
370	  the kernel if an affected CPU is detected.
371
372	  If unsure, say Y.
373
374config ARM64_ERRATUM_832075
375	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
376	default y
377	help
378	  This option adds an alternative code sequence to work around ARM
379	  erratum 832075 on Cortex-A57 parts up to r1p2.
380
381	  Affected Cortex-A57 parts might deadlock when exclusive load/store
382	  instructions to Write-Back memory are mixed with Device loads.
383
384	  The workaround is to promote device loads to use Load-Acquire
385	  semantics.
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_834220
393	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
394	depends on KVM
395	default y
396	help
397	  This option adds an alternative code sequence to work around ARM
398	  erratum 834220 on Cortex-A57 parts up to r1p2.
399
400	  Affected Cortex-A57 parts might report a Stage 2 translation
401	  fault as the result of a Stage 1 fault for load crossing a
402	  page boundary when there is a permission or device memory
403	  alignment fault at Stage 1 and a translation fault at Stage 2.
404
405	  The workaround is to verify that the Stage 1 translation
406	  doesn't generate a fault before handling the Stage 2 fault.
407	  Please note that this does not necessarily enable the workaround,
408	  as it depends on the alternative framework, which will only patch
409	  the kernel if an affected CPU is detected.
410
411	  If unsure, say Y.
412
413config ARM64_ERRATUM_845719
414	bool "Cortex-A53: 845719: a load might read incorrect data"
415	depends on COMPAT
416	default y
417	help
418	  This option adds an alternative code sequence to work around ARM
419	  erratum 845719 on Cortex-A53 parts up to r0p4.
420
421	  When running a compat (AArch32) userspace on an affected Cortex-A53
422	  part, a load at EL0 from a virtual address that matches the bottom 32
423	  bits of the virtual address used by a recent load at (AArch64) EL1
424	  might return incorrect data.
425
426	  The workaround is to write the contextidr_el1 register on exception
427	  return to a 32-bit task.
428	  Please note that this does not necessarily enable the workaround,
429	  as it depends on the alternative framework, which will only patch
430	  the kernel if an affected CPU is detected.
431
432	  If unsure, say Y.
433
434config ARM64_ERRATUM_843419
435	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
436	default y
437	select ARM64_MODULE_CMODEL_LARGE if MODULES
438	help
439	  This option links the kernel with '--fix-cortex-a53-843419' and
440	  builds modules using the large memory model in order to avoid the use
441	  of the ADRP instruction, which can cause a subsequent memory access
442	  to use an incorrect address on Cortex-A53 parts up to r0p4.
443
444	  If unsure, say Y.
445
446config CAVIUM_ERRATUM_22375
447	bool "Cavium erratum 22375, 24313"
448	default y
449	help
450	  Enable workaround for erratum 22375, 24313.
451
452	  This implements two gicv3-its errata workarounds for ThunderX. Both
453	  with small impact affecting only ITS table allocation.
454
455	    erratum 22375: only alloc 8MB table size
456	    erratum 24313: ignore memory access type
457
458	  The fixes are in ITS initialization and basically ignore memory access
459	  type and table size provided by the TYPER and BASER registers.
460
461	  If unsure, say Y.
462
463config CAVIUM_ERRATUM_23144
464	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
465	depends on NUMA
466	default y
467	help
468	  ITS SYNC command hang for cross node io and collections/cpu mapping.
469
470	  If unsure, say Y.
471
472config CAVIUM_ERRATUM_23154
473	bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
474	default y
475	help
476	  The gicv3 of ThunderX requires a modified version for
477	  reading the IAR status to ensure data synchronization
478	  (access to icc_iar1_el1 is not sync'ed before and after).
479
480	  If unsure, say Y.
481
482config CAVIUM_ERRATUM_27456
483	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
484	default y
485	help
486	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
487	  instructions may cause the icache to become corrupted if it
488	  contains data for a non-current ASID.  The fix is to
489	  invalidate the icache when changing the mm context.
490
491	  If unsure, say Y.
492
493config CAVIUM_ERRATUM_30115
494	bool "Cavium erratum 30115: Guest may disable interrupts in host"
495	default y
496	help
497	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
498	  1.2, and T83 Pass 1.0, KVM guest execution may disable
499	  interrupts in host. Trapping both GICv3 group-0 and group-1
500	  accesses sidesteps the issue.
501
502	  If unsure, say Y.
503
504config QCOM_FALKOR_ERRATUM_1003
505	bool "Falkor E1003: Incorrect translation due to ASID change"
506	default y
507	select ARM64_PAN if ARM64_SW_TTBR0_PAN
508	help
509	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
510	  and BADDR are changed together in TTBRx_EL1. The workaround for this
511	  issue is to use a reserved ASID in cpu_do_switch_mm() before
512	  switching to the new ASID. Saying Y here selects ARM64_PAN if
513	  ARM64_SW_TTBR0_PAN is selected. This is done because implementing and
514	  maintaining the E1003 workaround in the software PAN emulation code
515	  would be an unnecessary complication. The affected Falkor v1 CPU
516	  implements ARMv8.1 hardware PAN support and using hardware PAN
517	  support versus software PAN emulation is mutually exclusive at
518	  runtime.
519
520	  If unsure, say Y.
521
522config QCOM_FALKOR_ERRATUM_1009
523	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
524	default y
525	help
526	  On Falkor v1, the CPU may prematurely complete a DSB following a
527	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
528	  one more time to fix the issue.
529
530	  If unsure, say Y.
531
532config QCOM_QDF2400_ERRATUM_0065
533	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
534	default y
535	help
536	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
537	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
538	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
539
540	  If unsure, say Y.
541
542endmenu
543
544
545choice
546	prompt "Page size"
547	default ARM64_4K_PAGES
548	help
549	  Page size (translation granule) configuration.
550
551config ARM64_4K_PAGES
552	bool "4KB"
553	help
554	  This feature enables 4KB pages support.
555
556config ARM64_16K_PAGES
557	bool "16KB"
558	help
559	  The system will use 16KB pages support. AArch32 emulation
560	  requires applications compiled with 16K (or a multiple of 16K)
561	  aligned segments.
562
563config ARM64_64K_PAGES
564	bool "64KB"
565	help
566	  This feature enables 64KB pages support (4KB by default)
567	  allowing only two levels of page tables and faster TLB
568	  look-up. AArch32 emulation requires applications compiled
569	  with 64K aligned segments.
570
571endchoice
572
573choice
574	prompt "Virtual address space size"
575	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
576	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
577	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
578	help
579	  Allows choosing one of multiple possible virtual address
580	  space sizes. The level of translation table is determined by
581	  a combination of page size and virtual address space size.
582
583config ARM64_VA_BITS_36
584	bool "36-bit" if EXPERT
585	depends on ARM64_16K_PAGES
586
587config ARM64_VA_BITS_39
588	bool "39-bit"
589	depends on ARM64_4K_PAGES
590
591config ARM64_VA_BITS_42
592	bool "42-bit"
593	depends on ARM64_64K_PAGES
594
595config ARM64_VA_BITS_47
596	bool "47-bit"
597	depends on ARM64_16K_PAGES
598
599config ARM64_VA_BITS_48
600	bool "48-bit"
601
602endchoice
603
604config ARM64_VA_BITS
605	int
606	default 36 if ARM64_VA_BITS_36
607	default 39 if ARM64_VA_BITS_39
608	default 42 if ARM64_VA_BITS_42
609	default 47 if ARM64_VA_BITS_47
610	default 48 if ARM64_VA_BITS_48
611
612config CPU_BIG_ENDIAN
613       bool "Build big-endian kernel"
614       help
615         Say Y if you plan on running a kernel in big-endian mode.
616
617config SCHED_MC
618	bool "Multi-core scheduler support"
619	help
620	  Multi-core scheduler support improves the CPU scheduler's decision
621	  making when dealing with multi-core CPU chips at a cost of slightly
622	  increased overhead in some places. If unsure say N here.
623
624config SCHED_SMT
625	bool "SMT scheduler support"
626	help
627	  Improves the CPU scheduler's decision making when dealing with
628	  MultiThreading at a cost of slightly increased overhead in some
629	  places. If unsure say N here.
630
631config NR_CPUS
632	int "Maximum number of CPUs (2-4096)"
633	range 2 4096
634	# These have to remain sorted largest to smallest
635	default "64"
636
637config HOTPLUG_CPU
638	bool "Support for hot-pluggable CPUs"
639	select GENERIC_IRQ_MIGRATION
640	help
641	  Say Y here to experiment with turning CPUs off and on.  CPUs
642	  can be controlled through /sys/devices/system/cpu.
643
644# Common NUMA Features
645config NUMA
646	bool "Numa Memory Allocation and Scheduler Support"
647	select ACPI_NUMA if ACPI
648	select OF_NUMA
649	help
650	  Enable NUMA (Non Uniform Memory Access) support.
651
652	  The kernel will try to allocate memory used by a CPU on the
653	  local memory of the CPU and add some more
654	  NUMA awareness to the kernel.
655
656config NODES_SHIFT
657	int "Maximum NUMA Nodes (as a power of 2)"
658	range 1 10
659	default "2"
660	depends on NEED_MULTIPLE_NODES
661	help
662	  Specify the maximum number of NUMA Nodes available on the target
663	  system.  Increases memory reserved to accommodate various tables.
664
665config USE_PERCPU_NUMA_NODE_ID
666	def_bool y
667	depends on NUMA
668
669config HAVE_SETUP_PER_CPU_AREA
670	def_bool y
671	depends on NUMA
672
673config NEED_PER_CPU_EMBED_FIRST_CHUNK
674	def_bool y
675	depends on NUMA
676
677config HOLES_IN_ZONE
678	def_bool y
679	depends on NUMA
680
681source kernel/Kconfig.preempt
682source kernel/Kconfig.hz
683
684config ARCH_SUPPORTS_DEBUG_PAGEALLOC
685	def_bool y
686
687config ARCH_HAS_HOLES_MEMORYMODEL
688	def_bool y if SPARSEMEM
689
690config ARCH_SPARSEMEM_ENABLE
691	def_bool y
692	select SPARSEMEM_VMEMMAP_ENABLE
693
694config ARCH_SPARSEMEM_DEFAULT
695	def_bool ARCH_SPARSEMEM_ENABLE
696
697config ARCH_SELECT_MEMORY_MODEL
698	def_bool ARCH_SPARSEMEM_ENABLE
699
700config HAVE_ARCH_PFN_VALID
701	def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
702
703config HW_PERF_EVENTS
704	def_bool y
705	depends on ARM_PMU
706
707config SYS_SUPPORTS_HUGETLBFS
708	def_bool y
709
710config ARCH_WANT_HUGE_PMD_SHARE
711	def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
712
713config ARCH_HAS_CACHE_LINE_SIZE
714	def_bool y
715
716source "mm/Kconfig"
717
718config SECCOMP
719	bool "Enable seccomp to safely compute untrusted bytecode"
720	---help---
721	  This kernel feature is useful for number crunching applications
722	  that may need to compute untrusted bytecode during their
723	  execution. By using pipes or other transports made available to
724	  the process as file descriptors supporting the read/write
725	  syscalls, it's possible to isolate those applications in
726	  their own address space using seccomp. Once seccomp is
727	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
728	  and the task is only allowed to execute a few safe syscalls
729	  defined by each seccomp mode.
730
731config PARAVIRT
732	bool "Enable paravirtualization code"
733	help
734	  This changes the kernel so it can modify itself when it is run
735	  under a hypervisor, potentially improving performance significantly
736	  over full virtualization.
737
738config PARAVIRT_TIME_ACCOUNTING
739	bool "Paravirtual steal time accounting"
740	select PARAVIRT
741	default n
742	help
743	  Select this option to enable fine granularity task steal time
744	  accounting. Time spent executing other tasks in parallel with
745	  the current vCPU is discounted from the vCPU power. To account for
746	  that, there can be a small performance impact.
747
748	  If in doubt, say N here.
749
750config KEXEC
751	depends on PM_SLEEP_SMP
752	select KEXEC_CORE
753	bool "kexec system call"
754	---help---
755	  kexec is a system call that implements the ability to shutdown your
756	  current kernel, and to start another kernel.  It is like a reboot
757	  but it is independent of the system firmware.   And like a reboot
758	  you can start any kernel with it, not just Linux.
759
760config CRASH_DUMP
761	bool "Build kdump crash kernel"
762	help
763	  Generate crash dump after being started by kexec. This should
764	  be normally only set in special crash dump kernels which are
765	  loaded in the main kernel with kexec-tools into a specially
766	  reserved region and then later executed after a crash by
767	  kdump/kexec.
768
769	  For more details see Documentation/kdump/kdump.txt
770
771config XEN_DOM0
772	def_bool y
773	depends on XEN
774
775config XEN
776	bool "Xen guest support on ARM64"
777	depends on ARM64 && OF
778	select SWIOTLB_XEN
779	select PARAVIRT
780	help
781	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
782
783config FORCE_MAX_ZONEORDER
784	int
785	default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
786	default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
787	default "11"
788	help
789	  The kernel memory allocator divides physically contiguous memory
790	  blocks into "zones", where each zone is a power of two number of
791	  pages.  This option selects the largest power of two that the kernel
792	  keeps in the memory allocator.  If you need to allocate very large
793	  blocks of physically contiguous memory, then you may need to
794	  increase this value.
795
796	  This config option is actually maximum order plus one. For example,
797	  a value of 11 means that the largest free memory block is 2^10 pages.
798
799	  We make sure that we can allocate upto a HugePage size for each configuration.
800	  Hence we have :
801		MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
802
803	  However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
804	  4M allocations matching the default size used by generic code.
805
806menuconfig ARMV8_DEPRECATED
807	bool "Emulate deprecated/obsolete ARMv8 instructions"
808	depends on COMPAT
809	help
810	  Legacy software support may require certain instructions
811	  that have been deprecated or obsoleted in the architecture.
812
813	  Enable this config to enable selective emulation of these
814	  features.
815
816	  If unsure, say Y
817
818if ARMV8_DEPRECATED
819
820config SWP_EMULATION
821	bool "Emulate SWP/SWPB instructions"
822	help
823	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
824	  they are always undefined. Say Y here to enable software
825	  emulation of these instructions for userspace using LDXR/STXR.
826
827	  In some older versions of glibc [<=2.8] SWP is used during futex
828	  trylock() operations with the assumption that the code will not
829	  be preempted. This invalid assumption may be more likely to fail
830	  with SWP emulation enabled, leading to deadlock of the user
831	  application.
832
833	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
834	  on an external transaction monitoring block called a global
835	  monitor to maintain update atomicity. If your system does not
836	  implement a global monitor, this option can cause programs that
837	  perform SWP operations to uncached memory to deadlock.
838
839	  If unsure, say Y
840
841config CP15_BARRIER_EMULATION
842	bool "Emulate CP15 Barrier instructions"
843	help
844	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
845	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
846	  strongly recommended to use the ISB, DSB, and DMB
847	  instructions instead.
848
849	  Say Y here to enable software emulation of these
850	  instructions for AArch32 userspace code. When this option is
851	  enabled, CP15 barrier usage is traced which can help
852	  identify software that needs updating.
853
854	  If unsure, say Y
855
856config SETEND_EMULATION
857	bool "Emulate SETEND instruction"
858	help
859	  The SETEND instruction alters the data-endianness of the
860	  AArch32 EL0, and is deprecated in ARMv8.
861
862	  Say Y here to enable software emulation of the instruction
863	  for AArch32 userspace code.
864
865	  Note: All the cpus on the system must have mixed endian support at EL0
866	  for this feature to be enabled. If a new CPU - which doesn't support mixed
867	  endian - is hotplugged in after this feature has been enabled, there could
868	  be unexpected results in the applications.
869
870	  If unsure, say Y
871endif
872
873config ARM64_SW_TTBR0_PAN
874	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
875	help
876	  Enabling this option prevents the kernel from accessing
877	  user-space memory directly by pointing TTBR0_EL1 to a reserved
878	  zeroed area and reserved ASID. The user access routines
879	  restore the valid TTBR0_EL1 temporarily.
880
881menu "ARMv8.1 architectural features"
882
883config ARM64_HW_AFDBM
884	bool "Support for hardware updates of the Access and Dirty page flags"
885	default y
886	help
887	  The ARMv8.1 architecture extensions introduce support for
888	  hardware updates of the access and dirty information in page
889	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
890	  capable processors, accesses to pages with PTE_AF cleared will
891	  set this bit instead of raising an access flag fault.
892	  Similarly, writes to read-only pages with the DBM bit set will
893	  clear the read-only bit (AP[2]) instead of raising a
894	  permission fault.
895
896	  Kernels built with this configuration option enabled continue
897	  to work on pre-ARMv8.1 hardware and the performance impact is
898	  minimal. If unsure, say Y.
899
900config ARM64_PAN
901	bool "Enable support for Privileged Access Never (PAN)"
902	default y
903	help
904	 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
905	 prevents the kernel or hypervisor from accessing user-space (EL0)
906	 memory directly.
907
908	 Choosing this option will cause any unprotected (not using
909	 copy_to_user et al) memory access to fail with a permission fault.
910
911	 The feature is detected at runtime, and will remain as a 'nop'
912	 instruction if the cpu does not implement the feature.
913
914config ARM64_LSE_ATOMICS
915	bool "Atomic instructions"
916	help
917	  As part of the Large System Extensions, ARMv8.1 introduces new
918	  atomic instructions that are designed specifically to scale in
919	  very large systems.
920
921	  Say Y here to make use of these instructions for the in-kernel
922	  atomic routines. This incurs a small overhead on CPUs that do
923	  not support these instructions and requires the kernel to be
924	  built with binutils >= 2.25.
925
926config ARM64_VHE
927	bool "Enable support for Virtualization Host Extensions (VHE)"
928	default y
929	help
930	  Virtualization Host Extensions (VHE) allow the kernel to run
931	  directly at EL2 (instead of EL1) on processors that support
932	  it. This leads to better performance for KVM, as they reduce
933	  the cost of the world switch.
934
935	  Selecting this option allows the VHE feature to be detected
936	  at runtime, and does not affect processors that do not
937	  implement this feature.
938
939endmenu
940
941menu "ARMv8.2 architectural features"
942
943config ARM64_UAO
944	bool "Enable support for User Access Override (UAO)"
945	default y
946	help
947	  User Access Override (UAO; part of the ARMv8.2 Extensions)
948	  causes the 'unprivileged' variant of the load/store instructions to
949	  be overriden to be privileged.
950
951	  This option changes get_user() and friends to use the 'unprivileged'
952	  variant of the load/store instructions. This ensures that user-space
953	  really did have access to the supplied memory. When addr_limit is
954	  set to kernel memory the UAO bit will be set, allowing privileged
955	  access to kernel memory.
956
957	  Choosing this option will cause copy_to_user() et al to use user-space
958	  memory permissions.
959
960	  The feature is detected at runtime, the kernel will use the
961	  regular load/store instructions if the cpu does not implement the
962	  feature.
963
964config ARM64_PMEM
965	bool "Enable support for persistent memory"
966	select ARCH_HAS_PMEM_API
967	select ARCH_HAS_UACCESS_FLUSHCACHE
968	help
969	  Say Y to enable support for the persistent memory API based on the
970	  ARMv8.2 DCPoP feature.
971
972	  The feature is detected at runtime, and the kernel will use DC CVAC
973	  operations if DC CVAP is not supported (following the behaviour of
974	  DC CVAP itself if the system does not define a point of persistence).
975
976endmenu
977
978config ARM64_MODULE_CMODEL_LARGE
979	bool
980
981config ARM64_MODULE_PLTS
982	bool
983	select ARM64_MODULE_CMODEL_LARGE
984	select HAVE_MOD_ARCH_SPECIFIC
985
986config RELOCATABLE
987	bool
988	help
989	  This builds the kernel as a Position Independent Executable (PIE),
990	  which retains all relocation metadata required to relocate the
991	  kernel binary at runtime to a different virtual address than the
992	  address it was linked at.
993	  Since AArch64 uses the RELA relocation format, this requires a
994	  relocation pass at runtime even if the kernel is loaded at the
995	  same address it was linked at.
996
997config RANDOMIZE_BASE
998	bool "Randomize the address of the kernel image"
999	select ARM64_MODULE_PLTS if MODULES
1000	select RELOCATABLE
1001	help
1002	  Randomizes the virtual address at which the kernel image is
1003	  loaded, as a security feature that deters exploit attempts
1004	  relying on knowledge of the location of kernel internals.
1005
1006	  It is the bootloader's job to provide entropy, by passing a
1007	  random u64 value in /chosen/kaslr-seed at kernel entry.
1008
1009	  When booting via the UEFI stub, it will invoke the firmware's
1010	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1011	  to the kernel proper. In addition, it will randomise the physical
1012	  location of the kernel Image as well.
1013
1014	  If unsure, say N.
1015
1016config RANDOMIZE_MODULE_REGION_FULL
1017	bool "Randomize the module region independently from the core kernel"
1018	depends on RANDOMIZE_BASE
1019	default y
1020	help
1021	  Randomizes the location of the module region without considering the
1022	  location of the core kernel. This way, it is impossible for modules
1023	  to leak information about the location of core kernel data structures
1024	  but it does imply that function calls between modules and the core
1025	  kernel will need to be resolved via veneers in the module PLT.
1026
1027	  When this option is not set, the module region will be randomized over
1028	  a limited range that contains the [_stext, _etext] interval of the
1029	  core kernel, so branch relocations are always in range.
1030
1031endmenu
1032
1033menu "Boot options"
1034
1035config ARM64_ACPI_PARKING_PROTOCOL
1036	bool "Enable support for the ARM64 ACPI parking protocol"
1037	depends on ACPI
1038	help
1039	  Enable support for the ARM64 ACPI parking protocol. If disabled
1040	  the kernel will not allow booting through the ARM64 ACPI parking
1041	  protocol even if the corresponding data is present in the ACPI
1042	  MADT table.
1043
1044config CMDLINE
1045	string "Default kernel command string"
1046	default ""
1047	help
1048	  Provide a set of default command-line options at build time by
1049	  entering them here. As a minimum, you should specify the the
1050	  root device (e.g. root=/dev/nfs).
1051
1052config CMDLINE_FORCE
1053	bool "Always use the default kernel command string"
1054	help
1055	  Always use the default kernel command string, even if the boot
1056	  loader passes other arguments to the kernel.
1057	  This is useful if you cannot or don't want to change the
1058	  command-line options your boot loader passes to the kernel.
1059
1060config EFI_STUB
1061	bool
1062
1063config EFI
1064	bool "UEFI runtime support"
1065	depends on OF && !CPU_BIG_ENDIAN
1066	select LIBFDT
1067	select UCS2_STRING
1068	select EFI_PARAMS_FROM_FDT
1069	select EFI_RUNTIME_WRAPPERS
1070	select EFI_STUB
1071	select EFI_ARMSTUB
1072	default y
1073	help
1074	  This option provides support for runtime services provided
1075	  by UEFI firmware (such as non-volatile variables, realtime
1076          clock, and platform reset). A UEFI stub is also provided to
1077	  allow the kernel to be booted as an EFI application. This
1078	  is only useful on systems that have UEFI firmware.
1079
1080config DMI
1081	bool "Enable support for SMBIOS (DMI) tables"
1082	depends on EFI
1083	default y
1084	help
1085	  This enables SMBIOS/DMI feature for systems.
1086
1087	  This option is only useful on systems that have UEFI firmware.
1088	  However, even with this option, the resultant kernel should
1089	  continue to boot on existing non-UEFI platforms.
1090
1091endmenu
1092
1093menu "Userspace binary formats"
1094
1095source "fs/Kconfig.binfmt"
1096
1097config COMPAT
1098	bool "Kernel support for 32-bit EL0"
1099	depends on ARM64_4K_PAGES || EXPERT
1100	select COMPAT_BINFMT_ELF if BINFMT_ELF
1101	select HAVE_UID16
1102	select OLD_SIGSUSPEND3
1103	select COMPAT_OLD_SIGACTION
1104	help
1105	  This option enables support for a 32-bit EL0 running under a 64-bit
1106	  kernel at EL1. AArch32-specific components such as system calls,
1107	  the user helper functions, VFP support and the ptrace interface are
1108	  handled appropriately by the kernel.
1109
1110	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1111	  that you will only be able to execute AArch32 binaries that were compiled
1112	  with page size aligned segments.
1113
1114	  If you want to execute 32-bit userspace applications, say Y.
1115
1116config SYSVIPC_COMPAT
1117	def_bool y
1118	depends on COMPAT && SYSVIPC
1119
1120endmenu
1121
1122menu "Power management options"
1123
1124source "kernel/power/Kconfig"
1125
1126config ARCH_HIBERNATION_POSSIBLE
1127	def_bool y
1128	depends on CPU_PM
1129
1130config ARCH_HIBERNATION_HEADER
1131	def_bool y
1132	depends on HIBERNATION
1133
1134config ARCH_SUSPEND_POSSIBLE
1135	def_bool y
1136
1137endmenu
1138
1139menu "CPU Power Management"
1140
1141source "drivers/cpuidle/Kconfig"
1142
1143source "drivers/cpufreq/Kconfig"
1144
1145endmenu
1146
1147source "net/Kconfig"
1148
1149source "drivers/Kconfig"
1150
1151source "drivers/firmware/Kconfig"
1152
1153source "drivers/acpi/Kconfig"
1154
1155source "fs/Kconfig"
1156
1157source "arch/arm64/kvm/Kconfig"
1158
1159source "arch/arm64/Kconfig.debug"
1160
1161source "security/Kconfig"
1162
1163source "crypto/Kconfig"
1164if CRYPTO
1165source "arch/arm64/crypto/Kconfig"
1166endif
1167
1168source "lib/Kconfig"
1169