Kconfig 42 KB

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  1. config 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_ATOMIC_RMW
  61. select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 || CC_IS_CLANG
  62. select ARCH_SUPPORTS_NUMA_BALANCING
  63. select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
  64. select ARCH_WANT_FRAME_POINTERS
  65. select ARCH_HAS_UBSAN_SANITIZE_ALL
  66. select ARM_AMBA
  67. select ARM_ARCH_TIMER
  68. select ARM_GIC
  69. select AUDIT_ARCH_COMPAT_GENERIC
  70. select ARM_GIC_V2M if PCI
  71. select ARM_GIC_V3
  72. select ARM_GIC_V3_ITS if PCI
  73. select ARM_PSCI_FW
  74. select BUILDTIME_EXTABLE_SORT
  75. select CLONE_BACKWARDS
  76. select COMMON_CLK
  77. select CPU_PM if (SUSPEND || CPU_IDLE)
  78. select CRC32
  79. select DCACHE_WORD_ACCESS
  80. select DMA_DIRECT_OPS
  81. select EDAC_SUPPORT
  82. select FRAME_POINTER
  83. select GENERIC_ALLOCATOR
  84. select GENERIC_ARCH_TOPOLOGY
  85. select GENERIC_CLOCKEVENTS
  86. select GENERIC_CLOCKEVENTS_BROADCAST
  87. select GENERIC_CPU_AUTOPROBE
  88. select GENERIC_CPU_VULNERABILITIES
  89. select GENERIC_EARLY_IOREMAP
  90. select GENERIC_IDLE_POLL_SETUP
  91. select GENERIC_IRQ_MULTI_HANDLER
  92. select GENERIC_IRQ_PROBE
  93. select GENERIC_IRQ_SHOW
  94. select GENERIC_IRQ_SHOW_LEVEL
  95. select GENERIC_PCI_IOMAP
  96. select GENERIC_SCHED_CLOCK
  97. select GENERIC_SMP_IDLE_THREAD
  98. select GENERIC_STRNCPY_FROM_USER
  99. select GENERIC_STRNLEN_USER
  100. select GENERIC_TIME_VSYSCALL
  101. select HANDLE_DOMAIN_IRQ
  102. select HARDIRQS_SW_RESEND
  103. select HAVE_ACPI_APEI if (ACPI && EFI)
  104. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  105. select HAVE_ARCH_AUDITSYSCALL
  106. select HAVE_ARCH_BITREVERSE
  107. select HAVE_ARCH_HUGE_VMAP
  108. select HAVE_ARCH_JUMP_LABEL
  109. select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
  110. select HAVE_ARCH_KGDB
  111. select HAVE_ARCH_MMAP_RND_BITS
  112. select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
  113. select HAVE_ARCH_PREL32_RELOCATIONS
  114. select HAVE_ARCH_SECCOMP_FILTER
  115. select HAVE_ARCH_STACKLEAK
  116. select HAVE_ARCH_THREAD_STRUCT_WHITELIST
  117. select HAVE_ARCH_TRACEHOOK
  118. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  119. select HAVE_ARCH_VMAP_STACK
  120. select HAVE_ARM_SMCCC
  121. select HAVE_EBPF_JIT
  122. select HAVE_C_RECORDMCOUNT
  123. select HAVE_CMPXCHG_DOUBLE
  124. select HAVE_CMPXCHG_LOCAL
  125. select HAVE_CONTEXT_TRACKING
  126. select HAVE_DEBUG_BUGVERBOSE
  127. select HAVE_DEBUG_KMEMLEAK
  128. select HAVE_DMA_CONTIGUOUS
  129. select HAVE_DYNAMIC_FTRACE
  130. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  131. select HAVE_FTRACE_MCOUNT_RECORD
  132. select HAVE_FUNCTION_TRACER
  133. select HAVE_FUNCTION_GRAPH_TRACER
  134. select HAVE_GCC_PLUGINS
  135. select HAVE_GENERIC_DMA_COHERENT
  136. select HAVE_HW_BREAKPOINT if PERF_EVENTS
  137. select HAVE_IRQ_TIME_ACCOUNTING
  138. select HAVE_MEMBLOCK
  139. select HAVE_MEMBLOCK_NODE_MAP if NUMA
  140. select HAVE_NMI
  141. select HAVE_PATA_PLATFORM
  142. select HAVE_PERF_EVENTS
  143. select HAVE_PERF_REGS
  144. select HAVE_PERF_USER_STACK_DUMP
  145. select HAVE_REGS_AND_STACK_ACCESS_API
  146. select HAVE_RCU_TABLE_FREE
  147. select HAVE_RSEQ
  148. select HAVE_STACKPROTECTOR
  149. select HAVE_SYSCALL_TRACEPOINTS
  150. select HAVE_KPROBES
  151. select HAVE_KRETPROBES
  152. select IOMMU_DMA if IOMMU_SUPPORT
  153. select IRQ_DOMAIN
  154. select IRQ_FORCED_THREADING
  155. select MODULES_USE_ELF_RELA
  156. select MULTI_IRQ_HANDLER
  157. select NEED_DMA_MAP_STATE
  158. select NEED_SG_DMA_LENGTH
  159. select NO_BOOTMEM
  160. select OF
  161. select OF_EARLY_FLATTREE
  162. select OF_RESERVED_MEM
  163. select PCI_ECAM if ACPI
  164. select POWER_RESET
  165. select POWER_SUPPLY
  166. select REFCOUNT_FULL
  167. select SPARSE_IRQ
  168. select SWIOTLB
  169. select SYSCTL_EXCEPTION_TRACE
  170. select THREAD_INFO_IN_TASK
  171. help
  172. ARM 64-bit (AArch64) Linux support.
  173. config 64BIT
  174. def_bool y
  175. config MMU
  176. def_bool y
  177. config ARM64_PAGE_SHIFT
  178. int
  179. default 16 if ARM64_64K_PAGES
  180. default 14 if ARM64_16K_PAGES
  181. default 12
  182. config ARM64_CONT_SHIFT
  183. int
  184. default 5 if ARM64_64K_PAGES
  185. default 7 if ARM64_16K_PAGES
  186. default 4
  187. config ARCH_MMAP_RND_BITS_MIN
  188. default 14 if ARM64_64K_PAGES
  189. default 16 if ARM64_16K_PAGES
  190. default 18
  191. # max bits determined by the following formula:
  192. # VA_BITS - PAGE_SHIFT - 3
  193. config ARCH_MMAP_RND_BITS_MAX
  194. default 19 if ARM64_VA_BITS=36
  195. default 24 if ARM64_VA_BITS=39
  196. default 27 if ARM64_VA_BITS=42
  197. default 30 if ARM64_VA_BITS=47
  198. default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
  199. default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
  200. default 33 if ARM64_VA_BITS=48
  201. default 14 if ARM64_64K_PAGES
  202. default 16 if ARM64_16K_PAGES
  203. default 18
  204. config ARCH_MMAP_RND_COMPAT_BITS_MIN
  205. default 7 if ARM64_64K_PAGES
  206. default 9 if ARM64_16K_PAGES
  207. default 11
  208. config ARCH_MMAP_RND_COMPAT_BITS_MAX
  209. default 16
  210. config NO_IOPORT_MAP
  211. def_bool y if !PCI
  212. config STACKTRACE_SUPPORT
  213. def_bool y
  214. config ILLEGAL_POINTER_VALUE
  215. hex
  216. default 0xdead000000000000
  217. config LOCKDEP_SUPPORT
  218. def_bool y
  219. config TRACE_IRQFLAGS_SUPPORT
  220. def_bool y
  221. config RWSEM_XCHGADD_ALGORITHM
  222. def_bool y
  223. config GENERIC_BUG
  224. def_bool y
  225. depends on BUG
  226. config GENERIC_BUG_RELATIVE_POINTERS
  227. def_bool y
  228. depends on GENERIC_BUG
  229. config GENERIC_HWEIGHT
  230. def_bool y
  231. config GENERIC_CSUM
  232. def_bool y
  233. config GENERIC_CALIBRATE_DELAY
  234. def_bool y
  235. config ZONE_DMA32
  236. bool "Support DMA32 zone" if EXPERT
  237. default y
  238. config HAVE_GENERIC_GUP
  239. def_bool y
  240. config SMP
  241. def_bool y
  242. config KERNEL_MODE_NEON
  243. def_bool y
  244. config FIX_EARLYCON_MEM
  245. def_bool y
  246. config PGTABLE_LEVELS
  247. int
  248. default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
  249. default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
  250. default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48
  251. default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
  252. default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
  253. default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
  254. config ARCH_SUPPORTS_UPROBES
  255. def_bool y
  256. config ARCH_PROC_KCORE_TEXT
  257. def_bool y
  258. source "arch/arm64/Kconfig.platforms"
  259. menu "Bus support"
  260. config PCI
  261. bool "PCI support"
  262. help
  263. This feature enables support for PCI bus system. If you say Y
  264. here, the kernel will include drivers and infrastructure code
  265. to support PCI bus devices.
  266. config PCI_DOMAINS
  267. def_bool PCI
  268. config PCI_DOMAINS_GENERIC
  269. def_bool PCI
  270. config PCI_SYSCALL
  271. def_bool PCI
  272. source "drivers/pci/Kconfig"
  273. endmenu
  274. menu "Kernel Features"
  275. menu "ARM errata workarounds via the alternatives framework"
  276. config ARM64_ERRATUM_826319
  277. bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
  278. default y
  279. help
  280. This option adds an alternative code sequence to work around ARM
  281. erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
  282. AXI master interface and an L2 cache.
  283. If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
  284. and is unable to accept a certain write via this interface, it will
  285. not progress on read data presented on the read data channel and the
  286. system can deadlock.
  287. The workaround promotes data cache clean instructions to
  288. data cache clean-and-invalidate.
  289. Please note that this does not necessarily enable the workaround,
  290. as it depends on the alternative framework, which will only patch
  291. the kernel if an affected CPU is detected.
  292. If unsure, say Y.
  293. config ARM64_ERRATUM_827319
  294. bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
  295. default y
  296. help
  297. This option adds an alternative code sequence to work around ARM
  298. erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
  299. master interface and an L2 cache.
  300. Under certain conditions this erratum can cause a clean line eviction
  301. to occur at the same time as another transaction to the same address
  302. on the AMBA 5 CHI interface, which can cause data corruption if the
  303. interconnect reorders the two transactions.
  304. The workaround promotes data cache clean instructions to
  305. data cache clean-and-invalidate.
  306. Please note that this does not necessarily enable the workaround,
  307. as it depends on the alternative framework, which will only patch
  308. the kernel if an affected CPU is detected.
  309. If unsure, say Y.
  310. config ARM64_ERRATUM_824069
  311. bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
  312. default y
  313. help
  314. This option adds an alternative code sequence to work around ARM
  315. erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
  316. to a coherent interconnect.
  317. If a Cortex-A53 processor is executing a store or prefetch for
  318. write instruction at the same time as a processor in another
  319. cluster is executing a cache maintenance operation to the same
  320. address, then this erratum might cause a clean cache line to be
  321. incorrectly marked as dirty.
  322. The workaround promotes data cache clean instructions to
  323. data cache clean-and-invalidate.
  324. Please note that this option does not necessarily enable the
  325. workaround, as it depends on the alternative framework, which will
  326. only patch the kernel if an affected CPU is detected.
  327. If unsure, say Y.
  328. config ARM64_ERRATUM_819472
  329. bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
  330. default y
  331. help
  332. This option adds an alternative code sequence to work around ARM
  333. erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
  334. present when it is connected to a coherent interconnect.
  335. If the processor is executing a load and store exclusive sequence at
  336. the same time as a processor in another cluster is executing a cache
  337. maintenance operation to the same address, then this erratum might
  338. cause data corruption.
  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. If unsure, say Y.
  345. config ARM64_ERRATUM_832075
  346. bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
  347. default y
  348. help
  349. This option adds an alternative code sequence to work around ARM
  350. erratum 832075 on Cortex-A57 parts up to r1p2.
  351. Affected Cortex-A57 parts might deadlock when exclusive load/store
  352. instructions to Write-Back memory are mixed with Device loads.
  353. The workaround is to promote device loads to use Load-Acquire
  354. semantics.
  355. Please note that this does not necessarily enable the workaround,
  356. as it depends on the alternative framework, which will only patch
  357. the kernel if an affected CPU is detected.
  358. If unsure, say Y.
  359. config ARM64_ERRATUM_834220
  360. bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
  361. depends on KVM
  362. default y
  363. help
  364. This option adds an alternative code sequence to work around ARM
  365. erratum 834220 on Cortex-A57 parts up to r1p2.
  366. Affected Cortex-A57 parts might report a Stage 2 translation
  367. fault as the result of a Stage 1 fault for load crossing a
  368. page boundary when there is a permission or device memory
  369. alignment fault at Stage 1 and a translation fault at Stage 2.
  370. The workaround is to verify that the Stage 1 translation
  371. doesn't generate a fault before handling the Stage 2 fault.
  372. Please note that this does not necessarily enable the workaround,
  373. as it depends on the alternative framework, which will only patch
  374. the kernel if an affected CPU is detected.
  375. If unsure, say Y.
  376. config ARM64_ERRATUM_845719
  377. bool "Cortex-A53: 845719: a load might read incorrect data"
  378. depends on COMPAT
  379. default y
  380. help
  381. This option adds an alternative code sequence to work around ARM
  382. erratum 845719 on Cortex-A53 parts up to r0p4.
  383. When running a compat (AArch32) userspace on an affected Cortex-A53
  384. part, a load at EL0 from a virtual address that matches the bottom 32
  385. bits of the virtual address used by a recent load at (AArch64) EL1
  386. might return incorrect data.
  387. The workaround is to write the contextidr_el1 register on exception
  388. return to a 32-bit task.
  389. Please note that this does not necessarily enable the workaround,
  390. as it depends on the alternative framework, which will only patch
  391. the kernel if an affected CPU is detected.
  392. If unsure, say Y.
  393. config ARM64_ERRATUM_843419
  394. bool "Cortex-A53: 843419: A load or store might access an incorrect address"
  395. default y
  396. select ARM64_MODULE_PLTS if MODULES
  397. help
  398. This option links the kernel with '--fix-cortex-a53-843419' and
  399. enables PLT support to replace certain ADRP instructions, which can
  400. cause subsequent memory accesses to use an incorrect address on
  401. Cortex-A53 parts up to r0p4.
  402. If unsure, say Y.
  403. config ARM64_ERRATUM_1024718
  404. bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
  405. default y
  406. help
  407. This option adds work around for Arm Cortex-A55 Erratum 1024718.
  408. Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
  409. update of the hardware dirty bit when the DBM/AP bits are updated
  410. without a break-before-make. The work around is to disable the usage
  411. of hardware DBM locally on the affected cores. CPUs not affected by
  412. erratum will continue to use the feature.
  413. If unsure, say Y.
  414. config ARM64_ERRATUM_1463225
  415. bool "Cortex-A76: Software Step might prevent interrupt recognition"
  416. default y
  417. help
  418. This option adds a workaround for Arm Cortex-A76 erratum 1463225.
  419. On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
  420. of a system call instruction (SVC) can prevent recognition of
  421. subsequent interrupts when software stepping is disabled in the
  422. exception handler of the system call and either kernel debugging
  423. is enabled or VHE is in use.
  424. Work around the erratum by triggering a dummy step exception
  425. when handling a system call from a task that is being stepped
  426. in a VHE configuration of the kernel.
  427. If unsure, say Y.
  428. config CAVIUM_ERRATUM_22375
  429. bool "Cavium erratum 22375, 24313"
  430. default y
  431. help
  432. Enable workaround for erratum 22375, 24313.
  433. This implements two gicv3-its errata workarounds for ThunderX. Both
  434. with small impact affecting only ITS table allocation.
  435. erratum 22375: only alloc 8MB table size
  436. erratum 24313: ignore memory access type
  437. The fixes are in ITS initialization and basically ignore memory access
  438. type and table size provided by the TYPER and BASER registers.
  439. If unsure, say Y.
  440. config CAVIUM_ERRATUM_23144
  441. bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
  442. depends on NUMA
  443. default y
  444. help
  445. ITS SYNC command hang for cross node io and collections/cpu mapping.
  446. If unsure, say Y.
  447. config CAVIUM_ERRATUM_23154
  448. bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
  449. default y
  450. help
  451. The gicv3 of ThunderX requires a modified version for
  452. reading the IAR status to ensure data synchronization
  453. (access to icc_iar1_el1 is not sync'ed before and after).
  454. If unsure, say Y.
  455. config CAVIUM_ERRATUM_27456
  456. bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
  457. default y
  458. help
  459. On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
  460. instructions may cause the icache to become corrupted if it
  461. contains data for a non-current ASID. The fix is to
  462. invalidate the icache when changing the mm context.
  463. If unsure, say Y.
  464. config CAVIUM_ERRATUM_30115
  465. bool "Cavium erratum 30115: Guest may disable interrupts in host"
  466. default y
  467. help
  468. On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
  469. 1.2, and T83 Pass 1.0, KVM guest execution may disable
  470. interrupts in host. Trapping both GICv3 group-0 and group-1
  471. accesses sidesteps the issue.
  472. If unsure, say Y.
  473. config QCOM_FALKOR_ERRATUM_1003
  474. bool "Falkor E1003: Incorrect translation due to ASID change"
  475. default y
  476. help
  477. On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
  478. and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
  479. in TTBR1_EL1, this situation only occurs in the entry trampoline and
  480. then only for entries in the walk cache, since the leaf translation
  481. is unchanged. Work around the erratum by invalidating the walk cache
  482. entries for the trampoline before entering the kernel proper.
  483. config QCOM_FALKOR_ERRATUM_1009
  484. bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
  485. default y
  486. help
  487. On Falkor v1, the CPU may prematurely complete a DSB following a
  488. TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
  489. one more time to fix the issue.
  490. If unsure, say Y.
  491. config QCOM_QDF2400_ERRATUM_0065
  492. bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
  493. default y
  494. help
  495. On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
  496. ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
  497. been indicated as 16Bytes (0xf), not 8Bytes (0x7).
  498. If unsure, say Y.
  499. config SOCIONEXT_SYNQUACER_PREITS
  500. bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
  501. default y
  502. help
  503. Socionext Synquacer SoCs implement a separate h/w block to generate
  504. MSI doorbell writes with non-zero values for the device ID.
  505. If unsure, say Y.
  506. config HISILICON_ERRATUM_161600802
  507. bool "Hip07 161600802: Erroneous redistributor VLPI base"
  508. default y
  509. help
  510. The HiSilicon Hip07 SoC usees the wrong redistributor base
  511. when issued ITS commands such as VMOVP and VMAPP, and requires
  512. a 128kB offset to be applied to the target address in this commands.
  513. If unsure, say Y.
  514. config QCOM_FALKOR_ERRATUM_E1041
  515. bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
  516. default y
  517. help
  518. Falkor CPU may speculatively fetch instructions from an improper
  519. memory location when MMU translation is changed from SCTLR_ELn[M]=1
  520. to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
  521. If unsure, say Y.
  522. endmenu
  523. choice
  524. prompt "Page size"
  525. default ARM64_4K_PAGES
  526. help
  527. Page size (translation granule) configuration.
  528. config ARM64_4K_PAGES
  529. bool "4KB"
  530. help
  531. This feature enables 4KB pages support.
  532. config ARM64_16K_PAGES
  533. bool "16KB"
  534. help
  535. The system will use 16KB pages support. AArch32 emulation
  536. requires applications compiled with 16K (or a multiple of 16K)
  537. aligned segments.
  538. config ARM64_64K_PAGES
  539. bool "64KB"
  540. help
  541. This feature enables 64KB pages support (4KB by default)
  542. allowing only two levels of page tables and faster TLB
  543. look-up. AArch32 emulation requires applications compiled
  544. with 64K aligned segments.
  545. endchoice
  546. choice
  547. prompt "Virtual address space size"
  548. default ARM64_VA_BITS_39 if ARM64_4K_PAGES
  549. default ARM64_VA_BITS_47 if ARM64_16K_PAGES
  550. default ARM64_VA_BITS_42 if ARM64_64K_PAGES
  551. help
  552. Allows choosing one of multiple possible virtual address
  553. space sizes. The level of translation table is determined by
  554. a combination of page size and virtual address space size.
  555. config ARM64_VA_BITS_36
  556. bool "36-bit" if EXPERT
  557. depends on ARM64_16K_PAGES
  558. config ARM64_VA_BITS_39
  559. bool "39-bit"
  560. depends on ARM64_4K_PAGES
  561. config ARM64_VA_BITS_42
  562. bool "42-bit"
  563. depends on ARM64_64K_PAGES
  564. config ARM64_VA_BITS_47
  565. bool "47-bit"
  566. depends on ARM64_16K_PAGES
  567. config ARM64_VA_BITS_48
  568. bool "48-bit"
  569. endchoice
  570. config ARM64_VA_BITS
  571. int
  572. default 36 if ARM64_VA_BITS_36
  573. default 39 if ARM64_VA_BITS_39
  574. default 42 if ARM64_VA_BITS_42
  575. default 47 if ARM64_VA_BITS_47
  576. default 48 if ARM64_VA_BITS_48
  577. choice
  578. prompt "Physical address space size"
  579. default ARM64_PA_BITS_48
  580. help
  581. Choose the maximum physical address range that the kernel will
  582. support.
  583. config ARM64_PA_BITS_48
  584. bool "48-bit"
  585. config ARM64_PA_BITS_52
  586. bool "52-bit (ARMv8.2)"
  587. depends on ARM64_64K_PAGES
  588. depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
  589. help
  590. Enable support for a 52-bit physical address space, introduced as
  591. part of the ARMv8.2-LPA extension.
  592. With this enabled, the kernel will also continue to work on CPUs that
  593. do not support ARMv8.2-LPA, but with some added memory overhead (and
  594. minor performance overhead).
  595. endchoice
  596. config ARM64_PA_BITS
  597. int
  598. default 48 if ARM64_PA_BITS_48
  599. default 52 if ARM64_PA_BITS_52
  600. config CPU_BIG_ENDIAN
  601. bool "Build big-endian kernel"
  602. help
  603. Say Y if you plan on running a kernel in big-endian mode.
  604. config SCHED_MC
  605. bool "Multi-core scheduler support"
  606. help
  607. Multi-core scheduler support improves the CPU scheduler's decision
  608. making when dealing with multi-core CPU chips at a cost of slightly
  609. increased overhead in some places. If unsure say N here.
  610. config SCHED_SMT
  611. bool "SMT scheduler support"
  612. help
  613. Improves the CPU scheduler's decision making when dealing with
  614. MultiThreading at a cost of slightly increased overhead in some
  615. places. If unsure say N here.
  616. config NR_CPUS
  617. int "Maximum number of CPUs (2-4096)"
  618. range 2 4096
  619. # These have to remain sorted largest to smallest
  620. default "64"
  621. config HOTPLUG_CPU
  622. bool "Support for hot-pluggable CPUs"
  623. select GENERIC_IRQ_MIGRATION
  624. help
  625. Say Y here to experiment with turning CPUs off and on. CPUs
  626. can be controlled through /sys/devices/system/cpu.
  627. # Common NUMA Features
  628. config NUMA
  629. bool "Numa Memory Allocation and Scheduler Support"
  630. select ACPI_NUMA if ACPI
  631. select OF_NUMA
  632. help
  633. Enable NUMA (Non Uniform Memory Access) support.
  634. The kernel will try to allocate memory used by a CPU on the
  635. local memory of the CPU and add some more
  636. NUMA awareness to the kernel.
  637. config NODES_SHIFT
  638. int "Maximum NUMA Nodes (as a power of 2)"
  639. range 1 10
  640. default "2"
  641. depends on NEED_MULTIPLE_NODES
  642. help
  643. Specify the maximum number of NUMA Nodes available on the target
  644. system. Increases memory reserved to accommodate various tables.
  645. config USE_PERCPU_NUMA_NODE_ID
  646. def_bool y
  647. depends on NUMA
  648. config HAVE_SETUP_PER_CPU_AREA
  649. def_bool y
  650. depends on NUMA
  651. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  652. def_bool y
  653. depends on NUMA
  654. config HOLES_IN_ZONE
  655. def_bool y
  656. source kernel/Kconfig.hz
  657. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  658. def_bool y
  659. config ARCH_HAS_HOLES_MEMORYMODEL
  660. def_bool y if SPARSEMEM
  661. config ARCH_SPARSEMEM_ENABLE
  662. def_bool y
  663. select SPARSEMEM_VMEMMAP_ENABLE
  664. config ARCH_SPARSEMEM_DEFAULT
  665. def_bool ARCH_SPARSEMEM_ENABLE
  666. config ARCH_SELECT_MEMORY_MODEL
  667. def_bool ARCH_SPARSEMEM_ENABLE
  668. config ARCH_FLATMEM_ENABLE
  669. def_bool !NUMA
  670. config HAVE_ARCH_PFN_VALID
  671. def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
  672. config HW_PERF_EVENTS
  673. def_bool y
  674. depends on ARM_PMU
  675. config SYS_SUPPORTS_HUGETLBFS
  676. def_bool y
  677. config ARCH_WANT_HUGE_PMD_SHARE
  678. def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
  679. config ARCH_HAS_CACHE_LINE_SIZE
  680. def_bool y
  681. config SECCOMP
  682. bool "Enable seccomp to safely compute untrusted bytecode"
  683. ---help---
  684. This kernel feature is useful for number crunching applications
  685. that may need to compute untrusted bytecode during their
  686. execution. By using pipes or other transports made available to
  687. the process as file descriptors supporting the read/write
  688. syscalls, it's possible to isolate those applications in
  689. their own address space using seccomp. Once seccomp is
  690. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  691. and the task is only allowed to execute a few safe syscalls
  692. defined by each seccomp mode.
  693. config PARAVIRT
  694. bool "Enable paravirtualization code"
  695. help
  696. This changes the kernel so it can modify itself when it is run
  697. under a hypervisor, potentially improving performance significantly
  698. over full virtualization.
  699. config PARAVIRT_TIME_ACCOUNTING
  700. bool "Paravirtual steal time accounting"
  701. select PARAVIRT
  702. default n
  703. help
  704. Select this option to enable fine granularity task steal time
  705. accounting. Time spent executing other tasks in parallel with
  706. the current vCPU is discounted from the vCPU power. To account for
  707. that, there can be a small performance impact.
  708. If in doubt, say N here.
  709. config KEXEC
  710. depends on PM_SLEEP_SMP
  711. select KEXEC_CORE
  712. bool "kexec system call"
  713. ---help---
  714. kexec is a system call that implements the ability to shutdown your
  715. current kernel, and to start another kernel. It is like a reboot
  716. but it is independent of the system firmware. And like a reboot
  717. you can start any kernel with it, not just Linux.
  718. config CRASH_DUMP
  719. bool "Build kdump crash kernel"
  720. help
  721. Generate crash dump after being started by kexec. This should
  722. be normally only set in special crash dump kernels which are
  723. loaded in the main kernel with kexec-tools into a specially
  724. reserved region and then later executed after a crash by
  725. kdump/kexec.
  726. For more details see Documentation/kdump/kdump.txt
  727. config XEN_DOM0
  728. def_bool y
  729. depends on XEN
  730. config XEN
  731. bool "Xen guest support on ARM64"
  732. depends on ARM64 && OF
  733. select SWIOTLB_XEN
  734. select PARAVIRT
  735. help
  736. Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
  737. config FORCE_MAX_ZONEORDER
  738. int
  739. default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
  740. default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
  741. default "11"
  742. help
  743. The kernel memory allocator divides physically contiguous memory
  744. blocks into "zones", where each zone is a power of two number of
  745. pages. This option selects the largest power of two that the kernel
  746. keeps in the memory allocator. If you need to allocate very large
  747. blocks of physically contiguous memory, then you may need to
  748. increase this value.
  749. This config option is actually maximum order plus one. For example,
  750. a value of 11 means that the largest free memory block is 2^10 pages.
  751. We make sure that we can allocate upto a HugePage size for each configuration.
  752. Hence we have :
  753. MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
  754. However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
  755. 4M allocations matching the default size used by generic code.
  756. config UNMAP_KERNEL_AT_EL0
  757. bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
  758. default y
  759. help
  760. Speculation attacks against some high-performance processors can
  761. be used to bypass MMU permission checks and leak kernel data to
  762. userspace. This can be defended against by unmapping the kernel
  763. when running in userspace, mapping it back in on exception entry
  764. via a trampoline page in the vector table.
  765. If unsure, say Y.
  766. config HARDEN_BRANCH_PREDICTOR
  767. bool "Harden the branch predictor against aliasing attacks" if EXPERT
  768. default y
  769. help
  770. Speculation attacks against some high-performance processors rely on
  771. being able to manipulate the branch predictor for a victim context by
  772. executing aliasing branches in the attacker context. Such attacks
  773. can be partially mitigated against by clearing internal branch
  774. predictor state and limiting the prediction logic in some situations.
  775. This config option will take CPU-specific actions to harden the
  776. branch predictor against aliasing attacks and may rely on specific
  777. instruction sequences or control bits being set by the system
  778. firmware.
  779. If unsure, say Y.
  780. config HARDEN_EL2_VECTORS
  781. bool "Harden EL2 vector mapping against system register leak" if EXPERT
  782. default y
  783. help
  784. Speculation attacks against some high-performance processors can
  785. be used to leak privileged information such as the vector base
  786. register, resulting in a potential defeat of the EL2 layout
  787. randomization.
  788. This config option will map the vectors to a fixed location,
  789. independent of the EL2 code mapping, so that revealing VBAR_EL2
  790. to an attacker does not give away any extra information. This
  791. only gets enabled on affected CPUs.
  792. If unsure, say Y.
  793. config ARM64_SSBD
  794. bool "Speculative Store Bypass Disable" if EXPERT
  795. default y
  796. help
  797. This enables mitigation of the bypassing of previous stores
  798. by speculative loads.
  799. If unsure, say Y.
  800. menuconfig ARMV8_DEPRECATED
  801. bool "Emulate deprecated/obsolete ARMv8 instructions"
  802. depends on COMPAT
  803. depends on SYSCTL
  804. help
  805. Legacy software support may require certain instructions
  806. that have been deprecated or obsoleted in the architecture.
  807. Enable this config to enable selective emulation of these
  808. features.
  809. If unsure, say Y
  810. if ARMV8_DEPRECATED
  811. config SWP_EMULATION
  812. bool "Emulate SWP/SWPB instructions"
  813. help
  814. ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
  815. they are always undefined. Say Y here to enable software
  816. emulation of these instructions for userspace using LDXR/STXR.
  817. In some older versions of glibc [<=2.8] SWP is used during futex
  818. trylock() operations with the assumption that the code will not
  819. be preempted. This invalid assumption may be more likely to fail
  820. with SWP emulation enabled, leading to deadlock of the user
  821. application.
  822. NOTE: when accessing uncached shared regions, LDXR/STXR rely
  823. on an external transaction monitoring block called a global
  824. monitor to maintain update atomicity. If your system does not
  825. implement a global monitor, this option can cause programs that
  826. perform SWP operations to uncached memory to deadlock.
  827. If unsure, say Y
  828. config CP15_BARRIER_EMULATION
  829. bool "Emulate CP15 Barrier instructions"
  830. help
  831. The CP15 barrier instructions - CP15ISB, CP15DSB, and
  832. CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
  833. strongly recommended to use the ISB, DSB, and DMB
  834. instructions instead.
  835. Say Y here to enable software emulation of these
  836. instructions for AArch32 userspace code. When this option is
  837. enabled, CP15 barrier usage is traced which can help
  838. identify software that needs updating.
  839. If unsure, say Y
  840. config SETEND_EMULATION
  841. bool "Emulate SETEND instruction"
  842. help
  843. The SETEND instruction alters the data-endianness of the
  844. AArch32 EL0, and is deprecated in ARMv8.
  845. Say Y here to enable software emulation of the instruction
  846. for AArch32 userspace code.
  847. Note: All the cpus on the system must have mixed endian support at EL0
  848. for this feature to be enabled. If a new CPU - which doesn't support mixed
  849. endian - is hotplugged in after this feature has been enabled, there could
  850. be unexpected results in the applications.
  851. If unsure, say Y
  852. endif
  853. config ARM64_SW_TTBR0_PAN
  854. bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
  855. help
  856. Enabling this option prevents the kernel from accessing
  857. user-space memory directly by pointing TTBR0_EL1 to a reserved
  858. zeroed area and reserved ASID. The user access routines
  859. restore the valid TTBR0_EL1 temporarily.
  860. menu "ARMv8.1 architectural features"
  861. config ARM64_HW_AFDBM
  862. bool "Support for hardware updates of the Access and Dirty page flags"
  863. default y
  864. help
  865. The ARMv8.1 architecture extensions introduce support for
  866. hardware updates of the access and dirty information in page
  867. table entries. When enabled in TCR_EL1 (HA and HD bits) on
  868. capable processors, accesses to pages with PTE_AF cleared will
  869. set this bit instead of raising an access flag fault.
  870. Similarly, writes to read-only pages with the DBM bit set will
  871. clear the read-only bit (AP[2]) instead of raising a
  872. permission fault.
  873. Kernels built with this configuration option enabled continue
  874. to work on pre-ARMv8.1 hardware and the performance impact is
  875. minimal. If unsure, say Y.
  876. config ARM64_PAN
  877. bool "Enable support for Privileged Access Never (PAN)"
  878. default y
  879. help
  880. Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
  881. prevents the kernel or hypervisor from accessing user-space (EL0)
  882. memory directly.
  883. Choosing this option will cause any unprotected (not using
  884. copy_to_user et al) memory access to fail with a permission fault.
  885. The feature is detected at runtime, and will remain as a 'nop'
  886. instruction if the cpu does not implement the feature.
  887. config ARM64_LSE_ATOMICS
  888. bool "Atomic instructions"
  889. default y
  890. help
  891. As part of the Large System Extensions, ARMv8.1 introduces new
  892. atomic instructions that are designed specifically to scale in
  893. very large systems.
  894. Say Y here to make use of these instructions for the in-kernel
  895. atomic routines. This incurs a small overhead on CPUs that do
  896. not support these instructions and requires the kernel to be
  897. built with binutils >= 2.25 in order for the new instructions
  898. to be used.
  899. config ARM64_VHE
  900. bool "Enable support for Virtualization Host Extensions (VHE)"
  901. default y
  902. help
  903. Virtualization Host Extensions (VHE) allow the kernel to run
  904. directly at EL2 (instead of EL1) on processors that support
  905. it. This leads to better performance for KVM, as they reduce
  906. the cost of the world switch.
  907. Selecting this option allows the VHE feature to be detected
  908. at runtime, and does not affect processors that do not
  909. implement this feature.
  910. endmenu
  911. menu "ARMv8.2 architectural features"
  912. config ARM64_UAO
  913. bool "Enable support for User Access Override (UAO)"
  914. default y
  915. help
  916. User Access Override (UAO; part of the ARMv8.2 Extensions)
  917. causes the 'unprivileged' variant of the load/store instructions to
  918. be overridden to be privileged.
  919. This option changes get_user() and friends to use the 'unprivileged'
  920. variant of the load/store instructions. This ensures that user-space
  921. really did have access to the supplied memory. When addr_limit is
  922. set to kernel memory the UAO bit will be set, allowing privileged
  923. access to kernel memory.
  924. Choosing this option will cause copy_to_user() et al to use user-space
  925. memory permissions.
  926. The feature is detected at runtime, the kernel will use the
  927. regular load/store instructions if the cpu does not implement the
  928. feature.
  929. config ARM64_PMEM
  930. bool "Enable support for persistent memory"
  931. select ARCH_HAS_PMEM_API
  932. select ARCH_HAS_UACCESS_FLUSHCACHE
  933. help
  934. Say Y to enable support for the persistent memory API based on the
  935. ARMv8.2 DCPoP feature.
  936. The feature is detected at runtime, and the kernel will use DC CVAC
  937. operations if DC CVAP is not supported (following the behaviour of
  938. DC CVAP itself if the system does not define a point of persistence).
  939. config ARM64_RAS_EXTN
  940. bool "Enable support for RAS CPU Extensions"
  941. default y
  942. help
  943. CPUs that support the Reliability, Availability and Serviceability
  944. (RAS) Extensions, part of ARMv8.2 are able to track faults and
  945. errors, classify them and report them to software.
  946. On CPUs with these extensions system software can use additional
  947. barriers to determine if faults are pending and read the
  948. classification from a new set of registers.
  949. Selecting this feature will allow the kernel to use these barriers
  950. and access the new registers if the system supports the extension.
  951. Platform RAS features may additionally depend on firmware support.
  952. endmenu
  953. config ARM64_SVE
  954. bool "ARM Scalable Vector Extension support"
  955. default y
  956. depends on !KVM || ARM64_VHE
  957. help
  958. The Scalable Vector Extension (SVE) is an extension to the AArch64
  959. execution state which complements and extends the SIMD functionality
  960. of the base architecture to support much larger vectors and to enable
  961. additional vectorisation opportunities.
  962. To enable use of this extension on CPUs that implement it, say Y.
  963. Note that for architectural reasons, firmware _must_ implement SVE
  964. support when running on SVE capable hardware. The required support
  965. is present in:
  966. * version 1.5 and later of the ARM Trusted Firmware
  967. * the AArch64 boot wrapper since commit 5e1261e08abf
  968. ("bootwrapper: SVE: Enable SVE for EL2 and below").
  969. For other firmware implementations, consult the firmware documentation
  970. or vendor.
  971. If you need the kernel to boot on SVE-capable hardware with broken
  972. firmware, you may need to say N here until you get your firmware
  973. fixed. Otherwise, you may experience firmware panics or lockups when
  974. booting the kernel. If unsure and you are not observing these
  975. symptoms, you should assume that it is safe to say Y.
  976. CPUs that support SVE are architecturally required to support the
  977. Virtualization Host Extensions (VHE), so the kernel makes no
  978. provision for supporting SVE alongside KVM without VHE enabled.
  979. Thus, you will need to enable CONFIG_ARM64_VHE if you want to support
  980. KVM in the same kernel image.
  981. config ARM64_MODULE_PLTS
  982. bool
  983. select HAVE_MOD_ARCH_SPECIFIC
  984. config RELOCATABLE
  985. bool
  986. help
  987. This builds the kernel as a Position Independent Executable (PIE),
  988. which retains all relocation metadata required to relocate the
  989. kernel binary at runtime to a different virtual address than the
  990. address it was linked at.
  991. Since AArch64 uses the RELA relocation format, this requires a
  992. relocation pass at runtime even if the kernel is loaded at the
  993. same address it was linked at.
  994. config RANDOMIZE_BASE
  995. bool "Randomize the address of the kernel image"
  996. select ARM64_MODULE_PLTS if MODULES
  997. select RELOCATABLE
  998. help
  999. Randomizes the virtual address at which the kernel image is
  1000. loaded, as a security feature that deters exploit attempts
  1001. relying on knowledge of the location of kernel internals.
  1002. It is the bootloader's job to provide entropy, by passing a
  1003. random u64 value in /chosen/kaslr-seed at kernel entry.
  1004. When booting via the UEFI stub, it will invoke the firmware's
  1005. EFI_RNG_PROTOCOL implementation (if available) to supply entropy
  1006. to the kernel proper. In addition, it will randomise the physical
  1007. location of the kernel Image as well.
  1008. If unsure, say N.
  1009. config RANDOMIZE_MODULE_REGION_FULL
  1010. bool "Randomize the module region over a 4 GB range"
  1011. depends on RANDOMIZE_BASE
  1012. default y
  1013. help
  1014. Randomizes the location of the module region inside a 4 GB window
  1015. covering the core kernel. This way, it is less likely for modules
  1016. to leak information about the location of core kernel data structures
  1017. but it does imply that function calls between modules and the core
  1018. kernel will need to be resolved via veneers in the module PLT.
  1019. When this option is not set, the module region will be randomized over
  1020. a limited range that contains the [_stext, _etext] interval of the
  1021. core kernel, so branch relocations are always in range.
  1022. endmenu
  1023. menu "Boot options"
  1024. config ARM64_ACPI_PARKING_PROTOCOL
  1025. bool "Enable support for the ARM64 ACPI parking protocol"
  1026. depends on ACPI
  1027. help
  1028. Enable support for the ARM64 ACPI parking protocol. If disabled
  1029. the kernel will not allow booting through the ARM64 ACPI parking
  1030. protocol even if the corresponding data is present in the ACPI
  1031. MADT table.
  1032. config CMDLINE
  1033. string "Default kernel command string"
  1034. default ""
  1035. help
  1036. Provide a set of default command-line options at build time by
  1037. entering them here. As a minimum, you should specify the the
  1038. root device (e.g. root=/dev/nfs).
  1039. config CMDLINE_FORCE
  1040. bool "Always use the default kernel command string"
  1041. help
  1042. Always use the default kernel command string, even if the boot
  1043. loader passes other arguments to the kernel.
  1044. This is useful if you cannot or don't want to change the
  1045. command-line options your boot loader passes to the kernel.
  1046. config EFI_STUB
  1047. bool
  1048. config EFI
  1049. bool "UEFI runtime support"
  1050. depends on OF && !CPU_BIG_ENDIAN
  1051. depends on KERNEL_MODE_NEON
  1052. select ARCH_SUPPORTS_ACPI
  1053. select LIBFDT
  1054. select UCS2_STRING
  1055. select EFI_PARAMS_FROM_FDT
  1056. select EFI_RUNTIME_WRAPPERS
  1057. select EFI_STUB
  1058. select EFI_ARMSTUB
  1059. default y
  1060. help
  1061. This option provides support for runtime services provided
  1062. by UEFI firmware (such as non-volatile variables, realtime
  1063. clock, and platform reset). A UEFI stub is also provided to
  1064. allow the kernel to be booted as an EFI application. This
  1065. is only useful on systems that have UEFI firmware.
  1066. config DMI
  1067. bool "Enable support for SMBIOS (DMI) tables"
  1068. depends on EFI
  1069. default y
  1070. help
  1071. This enables SMBIOS/DMI feature for systems.
  1072. This option is only useful on systems that have UEFI firmware.
  1073. However, even with this option, the resultant kernel should
  1074. continue to boot on existing non-UEFI platforms.
  1075. endmenu
  1076. config COMPAT
  1077. bool "Kernel support for 32-bit EL0"
  1078. depends on ARM64_4K_PAGES || EXPERT
  1079. select COMPAT_BINFMT_ELF if BINFMT_ELF
  1080. select HAVE_UID16
  1081. select OLD_SIGSUSPEND3
  1082. select COMPAT_OLD_SIGACTION
  1083. help
  1084. This option enables support for a 32-bit EL0 running under a 64-bit
  1085. kernel at EL1. AArch32-specific components such as system calls,
  1086. the user helper functions, VFP support and the ptrace interface are
  1087. handled appropriately by the kernel.
  1088. If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
  1089. that you will only be able to execute AArch32 binaries that were compiled
  1090. with page size aligned segments.
  1091. If you want to execute 32-bit userspace applications, say Y.
  1092. config SYSVIPC_COMPAT
  1093. def_bool y
  1094. depends on COMPAT && SYSVIPC
  1095. menu "Power management options"
  1096. source "kernel/power/Kconfig"
  1097. config ARCH_HIBERNATION_POSSIBLE
  1098. def_bool y
  1099. depends on CPU_PM
  1100. config ARCH_HIBERNATION_HEADER
  1101. def_bool y
  1102. depends on HIBERNATION
  1103. config ARCH_SUSPEND_POSSIBLE
  1104. def_bool y
  1105. endmenu
  1106. menu "CPU Power Management"
  1107. source "drivers/cpuidle/Kconfig"
  1108. source "drivers/cpufreq/Kconfig"
  1109. endmenu
  1110. source "drivers/firmware/Kconfig"
  1111. source "drivers/acpi/Kconfig"
  1112. source "arch/arm64/kvm/Kconfig"
  1113. if CRYPTO
  1114. source "arch/arm64/crypto/Kconfig"
  1115. endif