Kconfig 25 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_REDUCED_HARDWARE_ONLY if ACPI
  6. select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
  7. select ARCH_HAS_ELF_RANDOMIZE
  8. select ARCH_HAS_GCOV_PROFILE_ALL
  9. select ARCH_HAS_SG_CHAIN
  10. select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
  11. select ARCH_USE_CMPXCHG_LOCKREF
  12. select ARCH_SUPPORTS_ATOMIC_RMW
  13. select ARCH_WANT_OPTIONAL_GPIOLIB
  14. select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
  15. select ARCH_WANT_FRAME_POINTERS
  16. select ARM_AMBA
  17. select ARM_ARCH_TIMER
  18. select ARM_GIC
  19. select AUDIT_ARCH_COMPAT_GENERIC
  20. select ARM_GIC_V2M if PCI_MSI
  21. select ARM_GIC_V3
  22. select ARM_GIC_V3_ITS if PCI_MSI
  23. select ARM_PSCI_FW
  24. select BUILDTIME_EXTABLE_SORT
  25. select CLONE_BACKWARDS
  26. select COMMON_CLK
  27. select CPU_PM if (SUSPEND || CPU_IDLE)
  28. select DCACHE_WORD_ACCESS
  29. select EDAC_SUPPORT
  30. select FRAME_POINTER
  31. select GENERIC_ALLOCATOR
  32. select GENERIC_CLOCKEVENTS
  33. select GENERIC_CLOCKEVENTS_BROADCAST
  34. select GENERIC_CPU_AUTOPROBE
  35. select GENERIC_EARLY_IOREMAP
  36. select GENERIC_IDLE_POLL_SETUP
  37. select GENERIC_IRQ_PROBE
  38. select GENERIC_IRQ_SHOW
  39. select GENERIC_IRQ_SHOW_LEVEL
  40. select GENERIC_PCI_IOMAP
  41. select GENERIC_SCHED_CLOCK
  42. select GENERIC_SMP_IDLE_THREAD
  43. select GENERIC_STRNCPY_FROM_USER
  44. select GENERIC_STRNLEN_USER
  45. select GENERIC_TIME_VSYSCALL
  46. select HANDLE_DOMAIN_IRQ
  47. select HARDIRQS_SW_RESEND
  48. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  49. select HAVE_ARCH_AUDITSYSCALL
  50. select HAVE_ARCH_BITREVERSE
  51. select HAVE_ARCH_JUMP_LABEL
  52. select HAVE_ARCH_KASAN if SPARSEMEM_VMEMMAP && !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
  53. select HAVE_ARCH_KGDB
  54. select HAVE_ARCH_SECCOMP_FILTER
  55. select HAVE_ARCH_TRACEHOOK
  56. select HAVE_BPF_JIT
  57. select HAVE_EBPF_JIT
  58. select HAVE_C_RECORDMCOUNT
  59. select HAVE_CC_STACKPROTECTOR
  60. select HAVE_CMPXCHG_DOUBLE
  61. select HAVE_CMPXCHG_LOCAL
  62. select HAVE_DEBUG_BUGVERBOSE
  63. select HAVE_DEBUG_KMEMLEAK
  64. select HAVE_DMA_API_DEBUG
  65. select HAVE_DMA_ATTRS
  66. select HAVE_DMA_CONTIGUOUS
  67. select HAVE_DYNAMIC_FTRACE
  68. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  69. select HAVE_FTRACE_MCOUNT_RECORD
  70. select HAVE_FUNCTION_TRACER
  71. select HAVE_FUNCTION_GRAPH_TRACER
  72. select HAVE_GENERIC_DMA_COHERENT
  73. select HAVE_HW_BREAKPOINT if PERF_EVENTS
  74. select HAVE_MEMBLOCK
  75. select HAVE_PATA_PLATFORM
  76. select HAVE_PERF_EVENTS
  77. select HAVE_PERF_REGS
  78. select HAVE_PERF_USER_STACK_DUMP
  79. select HAVE_RCU_TABLE_FREE
  80. select HAVE_SYSCALL_TRACEPOINTS
  81. select IOMMU_DMA if IOMMU_SUPPORT
  82. select IRQ_DOMAIN
  83. select IRQ_FORCED_THREADING
  84. select MODULES_USE_ELF_RELA
  85. select NO_BOOTMEM
  86. select OF
  87. select OF_EARLY_FLATTREE
  88. select OF_RESERVED_MEM
  89. select PERF_USE_VMALLOC
  90. select POWER_RESET
  91. select POWER_SUPPLY
  92. select SPARSE_IRQ
  93. select SYSCTL_EXCEPTION_TRACE
  94. select HAVE_CONTEXT_TRACKING
  95. help
  96. ARM 64-bit (AArch64) Linux support.
  97. config 64BIT
  98. def_bool y
  99. config ARCH_PHYS_ADDR_T_64BIT
  100. def_bool y
  101. config MMU
  102. def_bool y
  103. config NO_IOPORT_MAP
  104. def_bool y if !PCI
  105. config STACKTRACE_SUPPORT
  106. def_bool y
  107. config ILLEGAL_POINTER_VALUE
  108. hex
  109. default 0xdead000000000000
  110. config LOCKDEP_SUPPORT
  111. def_bool y
  112. config TRACE_IRQFLAGS_SUPPORT
  113. def_bool y
  114. config RWSEM_XCHGADD_ALGORITHM
  115. def_bool y
  116. config GENERIC_BUG
  117. def_bool y
  118. depends on BUG
  119. config GENERIC_BUG_RELATIVE_POINTERS
  120. def_bool y
  121. depends on GENERIC_BUG
  122. config GENERIC_HWEIGHT
  123. def_bool y
  124. config GENERIC_CSUM
  125. def_bool y
  126. config GENERIC_CALIBRATE_DELAY
  127. def_bool y
  128. config ZONE_DMA
  129. def_bool y
  130. config HAVE_GENERIC_RCU_GUP
  131. def_bool y
  132. config ARCH_DMA_ADDR_T_64BIT
  133. def_bool y
  134. config NEED_DMA_MAP_STATE
  135. def_bool y
  136. config NEED_SG_DMA_LENGTH
  137. def_bool y
  138. config SMP
  139. def_bool y
  140. config SWIOTLB
  141. def_bool y
  142. config IOMMU_HELPER
  143. def_bool SWIOTLB
  144. config KERNEL_MODE_NEON
  145. def_bool y
  146. config FIX_EARLYCON_MEM
  147. def_bool y
  148. config PGTABLE_LEVELS
  149. int
  150. default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
  151. default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
  152. default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48
  153. default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
  154. default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
  155. default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
  156. source "init/Kconfig"
  157. source "kernel/Kconfig.freezer"
  158. source "arch/arm64/Kconfig.platforms"
  159. menu "Bus support"
  160. config PCI
  161. bool "PCI support"
  162. help
  163. This feature enables support for PCI bus system. If you say Y
  164. here, the kernel will include drivers and infrastructure code
  165. to support PCI bus devices.
  166. config PCI_DOMAINS
  167. def_bool PCI
  168. config PCI_DOMAINS_GENERIC
  169. def_bool PCI
  170. config PCI_SYSCALL
  171. def_bool PCI
  172. source "drivers/pci/Kconfig"
  173. source "drivers/pci/pcie/Kconfig"
  174. source "drivers/pci/hotplug/Kconfig"
  175. endmenu
  176. menu "Kernel Features"
  177. menu "ARM errata workarounds via the alternatives framework"
  178. config ARM64_ERRATUM_826319
  179. bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
  180. default y
  181. help
  182. This option adds an alternative code sequence to work around ARM
  183. erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
  184. AXI master interface and an L2 cache.
  185. If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
  186. and is unable to accept a certain write via this interface, it will
  187. not progress on read data presented on the read data channel and the
  188. system can deadlock.
  189. The workaround promotes data cache clean instructions to
  190. data cache clean-and-invalidate.
  191. Please note that this does not necessarily enable the workaround,
  192. as it depends on the alternative framework, which will only patch
  193. the kernel if an affected CPU is detected.
  194. If unsure, say Y.
  195. config ARM64_ERRATUM_827319
  196. bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
  197. default y
  198. help
  199. This option adds an alternative code sequence to work around ARM
  200. erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
  201. master interface and an L2 cache.
  202. Under certain conditions this erratum can cause a clean line eviction
  203. to occur at the same time as another transaction to the same address
  204. on the AMBA 5 CHI interface, which can cause data corruption if the
  205. interconnect reorders the two transactions.
  206. The workaround promotes data cache clean instructions to
  207. data cache clean-and-invalidate.
  208. Please note that this does not necessarily enable the workaround,
  209. as it depends on the alternative framework, which will only patch
  210. the kernel if an affected CPU is detected.
  211. If unsure, say Y.
  212. config ARM64_ERRATUM_824069
  213. bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
  214. default y
  215. help
  216. This option adds an alternative code sequence to work around ARM
  217. erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
  218. to a coherent interconnect.
  219. If a Cortex-A53 processor is executing a store or prefetch for
  220. write instruction at the same time as a processor in another
  221. cluster is executing a cache maintenance operation to the same
  222. address, then this erratum might cause a clean cache line to be
  223. incorrectly marked as dirty.
  224. The workaround promotes data cache clean instructions to
  225. data cache clean-and-invalidate.
  226. Please note that this option does not necessarily enable the
  227. workaround, as it depends on the alternative framework, which will
  228. only patch the kernel if an affected CPU is detected.
  229. If unsure, say Y.
  230. config ARM64_ERRATUM_819472
  231. bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
  232. default y
  233. help
  234. This option adds an alternative code sequence to work around ARM
  235. erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
  236. present when it is connected to a coherent interconnect.
  237. If the processor is executing a load and store exclusive sequence at
  238. the same time as a processor in another cluster is executing a cache
  239. maintenance operation to the same address, then this erratum might
  240. cause data corruption.
  241. The workaround promotes data cache clean instructions to
  242. data cache clean-and-invalidate.
  243. Please note that this does not necessarily enable the workaround,
  244. as it depends on the alternative framework, which will only patch
  245. the kernel if an affected CPU is detected.
  246. If unsure, say Y.
  247. config ARM64_ERRATUM_832075
  248. bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
  249. default y
  250. help
  251. This option adds an alternative code sequence to work around ARM
  252. erratum 832075 on Cortex-A57 parts up to r1p2.
  253. Affected Cortex-A57 parts might deadlock when exclusive load/store
  254. instructions to Write-Back memory are mixed with Device loads.
  255. The workaround is to promote device loads to use Load-Acquire
  256. semantics.
  257. Please note that this does not necessarily enable the workaround,
  258. as it depends on the alternative framework, which will only patch
  259. the kernel if an affected CPU is detected.
  260. If unsure, say Y.
  261. config ARM64_ERRATUM_834220
  262. bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
  263. depends on KVM
  264. default y
  265. help
  266. This option adds an alternative code sequence to work around ARM
  267. erratum 834220 on Cortex-A57 parts up to r1p2.
  268. Affected Cortex-A57 parts might report a Stage 2 translation
  269. fault as the result of a Stage 1 fault for load crossing a
  270. page boundary when there is a permission or device memory
  271. alignment fault at Stage 1 and a translation fault at Stage 2.
  272. The workaround is to verify that the Stage 1 translation
  273. doesn't generate a fault before handling the Stage 2 fault.
  274. Please note that this does not necessarily enable the workaround,
  275. as it depends on the alternative framework, which will only patch
  276. the kernel if an affected CPU is detected.
  277. If unsure, say Y.
  278. config ARM64_ERRATUM_845719
  279. bool "Cortex-A53: 845719: a load might read incorrect data"
  280. depends on COMPAT
  281. default y
  282. help
  283. This option adds an alternative code sequence to work around ARM
  284. erratum 845719 on Cortex-A53 parts up to r0p4.
  285. When running a compat (AArch32) userspace on an affected Cortex-A53
  286. part, a load at EL0 from a virtual address that matches the bottom 32
  287. bits of the virtual address used by a recent load at (AArch64) EL1
  288. might return incorrect data.
  289. The workaround is to write the contextidr_el1 register on exception
  290. return to a 32-bit task.
  291. Please note that this does not necessarily enable the workaround,
  292. as it depends on the alternative framework, which will only patch
  293. the kernel if an affected CPU is detected.
  294. If unsure, say Y.
  295. config ARM64_ERRATUM_843419
  296. bool "Cortex-A53: 843419: A load or store might access an incorrect address"
  297. depends on MODULES
  298. default y
  299. help
  300. This option builds kernel modules using the large memory model in
  301. order to avoid the use of the ADRP instruction, which can cause
  302. a subsequent memory access to use an incorrect address on Cortex-A53
  303. parts up to r0p4.
  304. Note that the kernel itself must be linked with a version of ld
  305. which fixes potentially affected ADRP instructions through the
  306. use of veneers.
  307. If unsure, say Y.
  308. config ARM64_ERRATUM_1024718
  309. bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
  310. default y
  311. help
  312. This option adds work around for Arm Cortex-A55 Erratum 1024718.
  313. Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
  314. update of the hardware dirty bit when the DBM/AP bits are updated
  315. without a break-before-make. The work around is to disable the usage
  316. of hardware DBM locally on the affected cores. CPUs not affected by
  317. erratum will continue to use the feature.
  318. If unsure, say Y.
  319. config CAVIUM_ERRATUM_22375
  320. bool "Cavium erratum 22375, 24313"
  321. default y
  322. help
  323. Enable workaround for erratum 22375, 24313.
  324. This implements two gicv3-its errata workarounds for ThunderX. Both
  325. with small impact affecting only ITS table allocation.
  326. erratum 22375: only alloc 8MB table size
  327. erratum 24313: ignore memory access type
  328. The fixes are in ITS initialization and basically ignore memory access
  329. type and table size provided by the TYPER and BASER registers.
  330. If unsure, say Y.
  331. config CAVIUM_ERRATUM_23144
  332. bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
  333. depends on NUMA
  334. default y
  335. help
  336. ITS SYNC command hang for cross node io and collections/cpu mapping.
  337. If unsure, say Y.
  338. config CAVIUM_ERRATUM_23154
  339. bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
  340. default y
  341. help
  342. The gicv3 of ThunderX requires a modified version for
  343. reading the IAR status to ensure data synchronization
  344. (access to icc_iar1_el1 is not sync'ed before and after).
  345. If unsure, say Y.
  346. config CAVIUM_ERRATUM_27456
  347. bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
  348. default y
  349. help
  350. On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
  351. instructions may cause the icache to become corrupted if it
  352. contains data for a non-current ASID. The fix is to
  353. invalidate the icache when changing the mm context.
  354. If unsure, say Y.
  355. endmenu
  356. choice
  357. prompt "Page size"
  358. default ARM64_4K_PAGES
  359. help
  360. Page size (translation granule) configuration.
  361. config ARM64_4K_PAGES
  362. bool "4KB"
  363. help
  364. This feature enables 4KB pages support.
  365. config ARM64_16K_PAGES
  366. bool "16KB"
  367. help
  368. The system will use 16KB pages support. AArch32 emulation
  369. requires applications compiled with 16K (or a multiple of 16K)
  370. aligned segments.
  371. config ARM64_64K_PAGES
  372. bool "64KB"
  373. help
  374. This feature enables 64KB pages support (4KB by default)
  375. allowing only two levels of page tables and faster TLB
  376. look-up. AArch32 emulation requires applications compiled
  377. with 64K aligned segments.
  378. endchoice
  379. choice
  380. prompt "Virtual address space size"
  381. default ARM64_VA_BITS_39 if ARM64_4K_PAGES
  382. default ARM64_VA_BITS_47 if ARM64_16K_PAGES
  383. default ARM64_VA_BITS_42 if ARM64_64K_PAGES
  384. help
  385. Allows choosing one of multiple possible virtual address
  386. space sizes. The level of translation table is determined by
  387. a combination of page size and virtual address space size.
  388. config ARM64_VA_BITS_36
  389. bool "36-bit" if EXPERT
  390. depends on ARM64_16K_PAGES
  391. config ARM64_VA_BITS_39
  392. bool "39-bit"
  393. depends on ARM64_4K_PAGES
  394. config ARM64_VA_BITS_42
  395. bool "42-bit"
  396. depends on ARM64_64K_PAGES
  397. config ARM64_VA_BITS_47
  398. bool "47-bit"
  399. depends on ARM64_16K_PAGES
  400. config ARM64_VA_BITS_48
  401. bool "48-bit"
  402. endchoice
  403. config ARM64_VA_BITS
  404. int
  405. default 36 if ARM64_VA_BITS_36
  406. default 39 if ARM64_VA_BITS_39
  407. default 42 if ARM64_VA_BITS_42
  408. default 47 if ARM64_VA_BITS_47
  409. default 48 if ARM64_VA_BITS_48
  410. config CPU_BIG_ENDIAN
  411. bool "Build big-endian kernel"
  412. help
  413. Say Y if you plan on running a kernel in big-endian mode.
  414. config SCHED_MC
  415. bool "Multi-core scheduler support"
  416. help
  417. Multi-core scheduler support improves the CPU scheduler's decision
  418. making when dealing with multi-core CPU chips at a cost of slightly
  419. increased overhead in some places. If unsure say N here.
  420. config SCHED_SMT
  421. bool "SMT scheduler support"
  422. help
  423. Improves the CPU scheduler's decision making when dealing with
  424. MultiThreading at a cost of slightly increased overhead in some
  425. places. If unsure say N here.
  426. config NR_CPUS
  427. int "Maximum number of CPUs (2-4096)"
  428. range 2 4096
  429. # These have to remain sorted largest to smallest
  430. default "64"
  431. config HOTPLUG_CPU
  432. bool "Support for hot-pluggable CPUs"
  433. select GENERIC_IRQ_MIGRATION
  434. help
  435. Say Y here to experiment with turning CPUs off and on. CPUs
  436. can be controlled through /sys/devices/system/cpu.
  437. source kernel/Kconfig.preempt
  438. source kernel/Kconfig.hz
  439. config ARCH_HAS_HOLES_MEMORYMODEL
  440. def_bool y if SPARSEMEM
  441. config ARCH_SPARSEMEM_ENABLE
  442. def_bool y
  443. select SPARSEMEM_VMEMMAP_ENABLE
  444. config ARCH_SPARSEMEM_DEFAULT
  445. def_bool ARCH_SPARSEMEM_ENABLE
  446. config ARCH_SELECT_MEMORY_MODEL
  447. def_bool ARCH_SPARSEMEM_ENABLE
  448. config HAVE_ARCH_PFN_VALID
  449. def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
  450. config HW_PERF_EVENTS
  451. def_bool y
  452. depends on ARM_PMU
  453. config SYS_SUPPORTS_HUGETLBFS
  454. def_bool y
  455. config ARCH_WANT_GENERAL_HUGETLB
  456. def_bool y
  457. config ARCH_WANT_HUGE_PMD_SHARE
  458. def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
  459. config HAVE_ARCH_TRANSPARENT_HUGEPAGE
  460. def_bool y
  461. config ARCH_HAS_CACHE_LINE_SIZE
  462. def_bool y
  463. source "mm/Kconfig"
  464. config SECCOMP
  465. bool "Enable seccomp to safely compute untrusted bytecode"
  466. ---help---
  467. This kernel feature is useful for number crunching applications
  468. that may need to compute untrusted bytecode during their
  469. execution. By using pipes or other transports made available to
  470. the process as file descriptors supporting the read/write
  471. syscalls, it's possible to isolate those applications in
  472. their own address space using seccomp. Once seccomp is
  473. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  474. and the task is only allowed to execute a few safe syscalls
  475. defined by each seccomp mode.
  476. config XEN_DOM0
  477. def_bool y
  478. depends on XEN
  479. config XEN
  480. bool "Xen guest support on ARM64"
  481. depends on ARM64 && OF
  482. select SWIOTLB_XEN
  483. help
  484. Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
  485. config FORCE_MAX_ZONEORDER
  486. int
  487. default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
  488. default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
  489. default "11"
  490. help
  491. The kernel memory allocator divides physically contiguous memory
  492. blocks into "zones", where each zone is a power of two number of
  493. pages. This option selects the largest power of two that the kernel
  494. keeps in the memory allocator. If you need to allocate very large
  495. blocks of physically contiguous memory, then you may need to
  496. increase this value.
  497. This config option is actually maximum order plus one. For example,
  498. a value of 11 means that the largest free memory block is 2^10 pages.
  499. We make sure that we can allocate upto a HugePage size for each configuration.
  500. Hence we have :
  501. MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
  502. However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
  503. 4M allocations matching the default size used by generic code.
  504. menuconfig ARMV8_DEPRECATED
  505. bool "Emulate deprecated/obsolete ARMv8 instructions"
  506. depends on COMPAT
  507. help
  508. Legacy software support may require certain instructions
  509. that have been deprecated or obsoleted in the architecture.
  510. Enable this config to enable selective emulation of these
  511. features.
  512. If unsure, say Y
  513. if ARMV8_DEPRECATED
  514. config SWP_EMULATION
  515. bool "Emulate SWP/SWPB instructions"
  516. help
  517. ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
  518. they are always undefined. Say Y here to enable software
  519. emulation of these instructions for userspace using LDXR/STXR.
  520. In some older versions of glibc [<=2.8] SWP is used during futex
  521. trylock() operations with the assumption that the code will not
  522. be preempted. This invalid assumption may be more likely to fail
  523. with SWP emulation enabled, leading to deadlock of the user
  524. application.
  525. NOTE: when accessing uncached shared regions, LDXR/STXR rely
  526. on an external transaction monitoring block called a global
  527. monitor to maintain update atomicity. If your system does not
  528. implement a global monitor, this option can cause programs that
  529. perform SWP operations to uncached memory to deadlock.
  530. If unsure, say Y
  531. config CP15_BARRIER_EMULATION
  532. bool "Emulate CP15 Barrier instructions"
  533. help
  534. The CP15 barrier instructions - CP15ISB, CP15DSB, and
  535. CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
  536. strongly recommended to use the ISB, DSB, and DMB
  537. instructions instead.
  538. Say Y here to enable software emulation of these
  539. instructions for AArch32 userspace code. When this option is
  540. enabled, CP15 barrier usage is traced which can help
  541. identify software that needs updating.
  542. If unsure, say Y
  543. config SETEND_EMULATION
  544. bool "Emulate SETEND instruction"
  545. help
  546. The SETEND instruction alters the data-endianness of the
  547. AArch32 EL0, and is deprecated in ARMv8.
  548. Say Y here to enable software emulation of the instruction
  549. for AArch32 userspace code.
  550. Note: All the cpus on the system must have mixed endian support at EL0
  551. for this feature to be enabled. If a new CPU - which doesn't support mixed
  552. endian - is hotplugged in after this feature has been enabled, there could
  553. be unexpected results in the applications.
  554. If unsure, say Y
  555. endif
  556. menu "ARMv8.1 architectural features"
  557. config ARM64_HW_AFDBM
  558. bool "Support for hardware updates of the Access and Dirty page flags"
  559. default y
  560. help
  561. The ARMv8.1 architecture extensions introduce support for
  562. hardware updates of the access and dirty information in page
  563. table entries. When enabled in TCR_EL1 (HA and HD bits) on
  564. capable processors, accesses to pages with PTE_AF cleared will
  565. set this bit instead of raising an access flag fault.
  566. Similarly, writes to read-only pages with the DBM bit set will
  567. clear the read-only bit (AP[2]) instead of raising a
  568. permission fault.
  569. Kernels built with this configuration option enabled continue
  570. to work on pre-ARMv8.1 hardware and the performance impact is
  571. minimal. If unsure, say Y.
  572. config ARM64_PAN
  573. bool "Enable support for Privileged Access Never (PAN)"
  574. default y
  575. help
  576. Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
  577. prevents the kernel or hypervisor from accessing user-space (EL0)
  578. memory directly.
  579. Choosing this option will cause any unprotected (not using
  580. copy_to_user et al) memory access to fail with a permission fault.
  581. The feature is detected at runtime, and will remain as a 'nop'
  582. instruction if the cpu does not implement the feature.
  583. config ARM64_LSE_ATOMICS
  584. bool "Atomic instructions"
  585. help
  586. As part of the Large System Extensions, ARMv8.1 introduces new
  587. atomic instructions that are designed specifically to scale in
  588. very large systems.
  589. Say Y here to make use of these instructions for the in-kernel
  590. atomic routines. This incurs a small overhead on CPUs that do
  591. not support these instructions and requires the kernel to be
  592. built with binutils >= 2.25.
  593. endmenu
  594. endmenu
  595. menu "Boot options"
  596. config CMDLINE
  597. string "Default kernel command string"
  598. default ""
  599. help
  600. Provide a set of default command-line options at build time by
  601. entering them here. As a minimum, you should specify the the
  602. root device (e.g. root=/dev/nfs).
  603. config CMDLINE_FORCE
  604. bool "Always use the default kernel command string"
  605. help
  606. Always use the default kernel command string, even if the boot
  607. loader passes other arguments to the kernel.
  608. This is useful if you cannot or don't want to change the
  609. command-line options your boot loader passes to the kernel.
  610. config EFI_STUB
  611. bool
  612. config EFI
  613. bool "UEFI runtime support"
  614. depends on OF && !CPU_BIG_ENDIAN
  615. select LIBFDT
  616. select UCS2_STRING
  617. select EFI_PARAMS_FROM_FDT
  618. select EFI_RUNTIME_WRAPPERS
  619. select EFI_STUB
  620. select EFI_ARMSTUB
  621. default y
  622. help
  623. This option provides support for runtime services provided
  624. by UEFI firmware (such as non-volatile variables, realtime
  625. clock, and platform reset). A UEFI stub is also provided to
  626. allow the kernel to be booted as an EFI application. This
  627. is only useful on systems that have UEFI firmware.
  628. config DMI
  629. bool "Enable support for SMBIOS (DMI) tables"
  630. depends on EFI
  631. default y
  632. help
  633. This enables SMBIOS/DMI feature for systems.
  634. This option is only useful on systems that have UEFI firmware.
  635. However, even with this option, the resultant kernel should
  636. continue to boot on existing non-UEFI platforms.
  637. endmenu
  638. menu "Userspace binary formats"
  639. source "fs/Kconfig.binfmt"
  640. config COMPAT
  641. bool "Kernel support for 32-bit EL0"
  642. depends on ARM64_4K_PAGES || EXPERT
  643. select COMPAT_BINFMT_ELF if BINFMT_ELF
  644. select HAVE_UID16
  645. select OLD_SIGSUSPEND3
  646. select COMPAT_OLD_SIGACTION
  647. help
  648. This option enables support for a 32-bit EL0 running under a 64-bit
  649. kernel at EL1. AArch32-specific components such as system calls,
  650. the user helper functions, VFP support and the ptrace interface are
  651. handled appropriately by the kernel.
  652. If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
  653. that you will only be able to execute AArch32 binaries that were compiled
  654. with page size aligned segments.
  655. If you want to execute 32-bit userspace applications, say Y.
  656. config SYSVIPC_COMPAT
  657. def_bool y
  658. depends on COMPAT && SYSVIPC
  659. config KEYS_COMPAT
  660. def_bool y
  661. depends on COMPAT && KEYS
  662. endmenu
  663. menu "Power management options"
  664. source "kernel/power/Kconfig"
  665. config ARCH_SUSPEND_POSSIBLE
  666. def_bool y
  667. endmenu
  668. menu "CPU Power Management"
  669. source "drivers/cpuidle/Kconfig"
  670. source "drivers/cpufreq/Kconfig"
  671. endmenu
  672. source "net/Kconfig"
  673. source "drivers/Kconfig"
  674. source "drivers/firmware/Kconfig"
  675. source "drivers/acpi/Kconfig"
  676. source "fs/Kconfig"
  677. source "arch/arm64/kvm/Kconfig"
  678. source "arch/arm64/Kconfig.debug"
  679. source "security/Kconfig"
  680. source "crypto/Kconfig"
  681. if CRYPTO
  682. source "arch/arm64/crypto/Kconfig"
  683. endif
  684. source "lib/Kconfig"