Kconfig 60 KB

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  1. # SPDX-License-Identifier: GPL-2.0
  2. config ARM
  3. bool
  4. default y
  5. select ARCH_32BIT_OFF_T
  6. select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE if HAVE_KRETPROBES && FRAME_POINTER && !ARM_UNWIND
  7. select ARCH_HAS_BINFMT_FLAT
  8. select ARCH_HAS_CPU_FINALIZE_INIT if MMU
  9. select ARCH_HAS_CURRENT_STACK_POINTER
  10. select ARCH_HAS_DEBUG_VIRTUAL if MMU
  11. select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE
  12. select ARCH_HAS_ELF_RANDOMIZE
  13. select ARCH_HAS_FORTIFY_SOURCE
  14. select ARCH_HAS_KEEPINITRD
  15. select ARCH_HAS_KCOV
  16. select ARCH_HAS_MEMBARRIER_SYNC_CORE
  17. select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
  18. select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
  19. select ARCH_HAS_SETUP_DMA_OPS
  20. select ARCH_HAS_SET_MEMORY
  21. select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
  22. select ARCH_HAS_STRICT_MODULE_RWX if MMU
  23. select ARCH_HAS_SYNC_DMA_FOR_DEVICE
  24. select ARCH_HAS_SYNC_DMA_FOR_CPU
  25. select ARCH_HAS_TEARDOWN_DMA_OPS if MMU
  26. select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
  27. select ARCH_HAVE_CUSTOM_GPIO_H
  28. select ARCH_HAVE_NMI_SAFE_CMPXCHG if CPU_V7 || CPU_V7M || CPU_V6K
  29. select ARCH_HAS_GCOV_PROFILE_ALL
  30. select ARCH_KEEP_MEMBLOCK
  31. select ARCH_MIGHT_HAVE_PC_PARPORT
  32. select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
  33. select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
  34. select ARCH_SUPPORTS_ATOMIC_RMW
  35. select ARCH_SUPPORTS_HUGETLBFS if ARM_LPAE
  36. select ARCH_USE_BUILTIN_BSWAP
  37. select ARCH_USE_CMPXCHG_LOCKREF
  38. select ARCH_USE_MEMTEST
  39. select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
  40. select ARCH_WANT_GENERAL_HUGETLB
  41. select ARCH_WANT_IPC_PARSE_VERSION
  42. select ARCH_WANT_LD_ORPHAN_WARN
  43. select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
  44. select BUILDTIME_TABLE_SORT if MMU
  45. select COMMON_CLK if !(ARCH_RPC || ARCH_FOOTBRIDGE)
  46. select CLONE_BACKWARDS
  47. select CPU_PM if SUSPEND || CPU_IDLE
  48. select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
  49. select DMA_DECLARE_COHERENT
  50. select DMA_GLOBAL_POOL if !MMU
  51. select DMA_OPS
  52. select DMA_NONCOHERENT_MMAP if MMU
  53. select EDAC_SUPPORT
  54. select EDAC_ATOMIC_SCRUB
  55. select GENERIC_ALLOCATOR
  56. select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
  57. select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
  58. select GENERIC_CLOCKEVENTS_BROADCAST if SMP
  59. select GENERIC_IRQ_IPI if SMP
  60. select GENERIC_CPU_AUTOPROBE
  61. select GENERIC_EARLY_IOREMAP
  62. select GENERIC_IDLE_POLL_SETUP
  63. select GENERIC_IRQ_MULTI_HANDLER
  64. select GENERIC_IRQ_PROBE
  65. select GENERIC_IRQ_SHOW
  66. select GENERIC_IRQ_SHOW_LEVEL
  67. select GENERIC_LIB_DEVMEM_IS_ALLOWED
  68. select GENERIC_PCI_IOMAP
  69. select GENERIC_SCHED_CLOCK
  70. select GENERIC_SMP_IDLE_THREAD
  71. select HARDIRQS_SW_RESEND
  72. select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
  73. select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
  74. select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
  75. select HAVE_ARCH_KFENCE if MMU && !XIP_KERNEL
  76. select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
  77. select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
  78. select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
  79. select HAVE_ARCH_MMAP_RND_BITS if MMU
  80. select HAVE_ARCH_PFN_VALID
  81. select HAVE_ARCH_SECCOMP
  82. select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT
  83. select HAVE_ARCH_THREAD_STRUCT_WHITELIST
  84. select HAVE_ARCH_TRACEHOOK
  85. select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARM_LPAE
  86. select HAVE_ARM_SMCCC if CPU_V7
  87. select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
  88. select HAVE_CONTEXT_TRACKING_USER
  89. select HAVE_C_RECORDMCOUNT
  90. select HAVE_BUILDTIME_MCOUNT_SORT
  91. select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL
  92. select HAVE_DMA_CONTIGUOUS if MMU
  93. select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
  94. select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
  95. select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
  96. select HAVE_EXIT_THREAD
  97. select HAVE_FAST_GUP if ARM_LPAE
  98. select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
  99. select HAVE_FUNCTION_GRAPH_TRACER
  100. select HAVE_FUNCTION_TRACER if !XIP_KERNEL
  101. select HAVE_GCC_PLUGINS
  102. select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7)
  103. select HAVE_IRQ_TIME_ACCOUNTING
  104. select HAVE_KERNEL_GZIP
  105. select HAVE_KERNEL_LZ4
  106. select HAVE_KERNEL_LZMA
  107. select HAVE_KERNEL_LZO
  108. select HAVE_KERNEL_XZ
  109. select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
  110. select HAVE_KRETPROBES if HAVE_KPROBES
  111. select HAVE_MOD_ARCH_SPECIFIC
  112. select HAVE_NMI
  113. select HAVE_OPTPROBES if !THUMB2_KERNEL
  114. select HAVE_PCI if MMU
  115. select HAVE_PERF_EVENTS
  116. select HAVE_PERF_REGS
  117. select HAVE_PERF_USER_STACK_DUMP
  118. select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
  119. select HAVE_REGS_AND_STACK_ACCESS_API
  120. select HAVE_RSEQ
  121. select HAVE_STACKPROTECTOR
  122. select HAVE_SYSCALL_TRACEPOINTS
  123. select HAVE_UID16
  124. select HAVE_VIRT_CPU_ACCOUNTING_GEN
  125. select IRQ_FORCED_THREADING
  126. select LOCK_MM_AND_FIND_VMA
  127. select MODULES_USE_ELF_REL
  128. select NEED_DMA_MAP_STATE
  129. select OF_EARLY_FLATTREE if OF
  130. select OLD_SIGACTION
  131. select OLD_SIGSUSPEND3
  132. select PCI_DOMAINS_GENERIC if PCI
  133. select PCI_SYSCALL if PCI
  134. select PERF_USE_VMALLOC
  135. select RTC_LIB
  136. select SPARSE_IRQ if !(ARCH_FOOTBRIDGE || ARCH_RPC)
  137. select SYS_SUPPORTS_APM_EMULATION
  138. select THREAD_INFO_IN_TASK
  139. select TIMER_OF if OF
  140. select HAVE_ARCH_VMAP_STACK if MMU && ARM_HAS_GROUP_RELOCS
  141. select TRACE_IRQFLAGS_SUPPORT if !CPU_V7M
  142. select USE_OF if !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
  143. # Above selects are sorted alphabetically; please add new ones
  144. # according to that. Thanks.
  145. help
  146. The ARM series is a line of low-power-consumption RISC chip designs
  147. licensed by ARM Ltd and targeted at embedded applications and
  148. handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
  149. manufactured, but legacy ARM-based PC hardware remains popular in
  150. Europe. There is an ARM Linux project with a web page at
  151. <http://www.arm.linux.org.uk/>.
  152. config ARM_HAS_GROUP_RELOCS
  153. def_bool y
  154. depends on !LD_IS_LLD || LLD_VERSION >= 140000
  155. depends on !COMPILE_TEST
  156. help
  157. Whether or not to use R_ARM_ALU_PC_Gn or R_ARM_LDR_PC_Gn group
  158. relocations, which have been around for a long time, but were not
  159. supported in LLD until version 14. The combined range is -/+ 256 MiB,
  160. which is usually sufficient, but not for allyesconfig, so we disable
  161. this feature when doing compile testing.
  162. config ARM_DMA_USE_IOMMU
  163. bool
  164. select NEED_SG_DMA_LENGTH
  165. if ARM_DMA_USE_IOMMU
  166. config ARM_DMA_IOMMU_ALIGNMENT
  167. int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
  168. range 4 9
  169. default 8
  170. help
  171. DMA mapping framework by default aligns all buffers to the smallest
  172. PAGE_SIZE order which is greater than or equal to the requested buffer
  173. size. This works well for buffers up to a few hundreds kilobytes, but
  174. for larger buffers it just a waste of address space. Drivers which has
  175. relatively small addressing window (like 64Mib) might run out of
  176. virtual space with just a few allocations.
  177. With this parameter you can specify the maximum PAGE_SIZE order for
  178. DMA IOMMU buffers. Larger buffers will be aligned only to this
  179. specified order. The order is expressed as a power of two multiplied
  180. by the PAGE_SIZE.
  181. endif
  182. config SYS_SUPPORTS_APM_EMULATION
  183. bool
  184. config HAVE_TCM
  185. bool
  186. select GENERIC_ALLOCATOR
  187. config HAVE_PROC_CPU
  188. bool
  189. config NO_IOPORT_MAP
  190. bool
  191. config SBUS
  192. bool
  193. config STACKTRACE_SUPPORT
  194. bool
  195. default y
  196. config LOCKDEP_SUPPORT
  197. bool
  198. default y
  199. config ARCH_HAS_ILOG2_U32
  200. bool
  201. config ARCH_HAS_ILOG2_U64
  202. bool
  203. config ARCH_HAS_BANDGAP
  204. bool
  205. config FIX_EARLYCON_MEM
  206. def_bool y if MMU
  207. config GENERIC_HWEIGHT
  208. bool
  209. default y
  210. config GENERIC_CALIBRATE_DELAY
  211. bool
  212. default y
  213. config ARCH_MAY_HAVE_PC_FDC
  214. bool
  215. config ARCH_SUPPORTS_UPROBES
  216. def_bool y
  217. config GENERIC_ISA_DMA
  218. bool
  219. config FIQ
  220. bool
  221. config ARCH_MTD_XIP
  222. bool
  223. config ARM_PATCH_PHYS_VIRT
  224. bool "Patch physical to virtual translations at runtime" if EMBEDDED
  225. default y
  226. depends on MMU
  227. help
  228. Patch phys-to-virt and virt-to-phys translation functions at
  229. boot and module load time according to the position of the
  230. kernel in system memory.
  231. This can only be used with non-XIP MMU kernels where the base
  232. of physical memory is at a 2 MiB boundary.
  233. Only disable this option if you know that you do not require
  234. this feature (eg, building a kernel for a single machine) and
  235. you need to shrink the kernel to the minimal size.
  236. config NEED_MACH_IO_H
  237. bool
  238. help
  239. Select this when mach/io.h is required to provide special
  240. definitions for this platform. The need for mach/io.h should
  241. be avoided when possible.
  242. config NEED_MACH_MEMORY_H
  243. bool
  244. help
  245. Select this when mach/memory.h is required to provide special
  246. definitions for this platform. The need for mach/memory.h should
  247. be avoided when possible.
  248. config PHYS_OFFSET
  249. hex "Physical address of main memory" if MMU
  250. depends on !ARM_PATCH_PHYS_VIRT || !AUTO_ZRELADDR
  251. default DRAM_BASE if !MMU
  252. default 0x00000000 if ARCH_FOOTBRIDGE
  253. default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
  254. default 0x30000000 if ARCH_S3C24XX
  255. default 0xa0000000 if ARCH_IOP32X || ARCH_PXA
  256. default 0xc0000000 if ARCH_EP93XX || ARCH_SA1100
  257. default 0
  258. help
  259. Please provide the physical address corresponding to the
  260. location of main memory in your system.
  261. config GENERIC_BUG
  262. def_bool y
  263. depends on BUG
  264. config PGTABLE_LEVELS
  265. int
  266. default 3 if ARM_LPAE
  267. default 2
  268. menu "System Type"
  269. config MMU
  270. bool "MMU-based Paged Memory Management Support"
  271. default y
  272. help
  273. Select if you want MMU-based virtualised addressing space
  274. support by paged memory management. If unsure, say 'Y'.
  275. config ARM_SINGLE_ARMV7M
  276. def_bool !MMU
  277. select ARM_NVIC
  278. select CPU_V7M
  279. select NO_IOPORT_MAP
  280. config ARCH_MMAP_RND_BITS_MIN
  281. default 8
  282. config ARCH_MMAP_RND_BITS_MAX
  283. default 14 if PAGE_OFFSET=0x40000000
  284. default 15 if PAGE_OFFSET=0x80000000
  285. default 16
  286. config ARCH_MULTIPLATFORM
  287. bool "Require kernel to be portable to multiple machines" if EXPERT
  288. depends on MMU && !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
  289. default y
  290. help
  291. In general, all Arm machines can be supported in a single
  292. kernel image, covering either Armv4/v5 or Armv6/v7.
  293. However, some configuration options require hardcoding machine
  294. specific physical addresses or enable errata workarounds that may
  295. break other machines.
  296. Selecting N here allows using those options, including
  297. DEBUG_UNCOMPRESS, XIP_KERNEL and ZBOOT_ROM. If unsure, say Y.
  298. menu "Platform selection"
  299. depends on MMU
  300. comment "CPU Core family selection"
  301. config ARCH_MULTI_V4
  302. bool "ARMv4 based platforms (FA526, StrongARM)"
  303. depends on !ARCH_MULTI_V6_V7
  304. select ARCH_MULTI_V4_V5
  305. select CPU_FA526 if !(CPU_SA110 || CPU_SA1100)
  306. config ARCH_MULTI_V4T
  307. bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
  308. depends on !ARCH_MULTI_V6_V7
  309. select ARCH_MULTI_V4_V5
  310. select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
  311. CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
  312. CPU_ARM925T || CPU_ARM940T)
  313. config ARCH_MULTI_V5
  314. bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
  315. depends on !ARCH_MULTI_V6_V7
  316. select ARCH_MULTI_V4_V5
  317. select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
  318. CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
  319. CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
  320. config ARCH_MULTI_V4_V5
  321. bool
  322. config ARCH_MULTI_V6
  323. bool "ARMv6 based platforms (ARM11)"
  324. select ARCH_MULTI_V6_V7
  325. select CPU_V6K
  326. config ARCH_MULTI_V7
  327. bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
  328. default y
  329. select ARCH_MULTI_V6_V7
  330. select CPU_V7
  331. select HAVE_SMP
  332. config ARCH_MULTI_V6_V7
  333. bool
  334. select MIGHT_HAVE_CACHE_L2X0
  335. config ARCH_MULTI_CPU_AUTO
  336. def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
  337. select ARCH_MULTI_V5
  338. endmenu
  339. config ARCH_VIRT
  340. bool "Dummy Virtual Machine"
  341. depends on ARCH_MULTI_V7
  342. select ARM_AMBA
  343. select ARM_GIC
  344. select ARM_GIC_V2M if PCI
  345. select ARM_GIC_V3
  346. select ARM_GIC_V3_ITS if PCI
  347. select ARM_PSCI
  348. select HAVE_ARM_ARCH_TIMER
  349. config ARCH_AIROHA
  350. bool "Airoha SoC Support"
  351. depends on ARCH_MULTI_V7
  352. select ARM_AMBA
  353. select ARM_GIC
  354. select ARM_GIC_V3
  355. select ARM_PSCI
  356. select HAVE_ARM_ARCH_TIMER
  357. help
  358. Support for Airoha EN7523 SoCs
  359. #
  360. # This is sorted alphabetically by mach-* pathname. However, plat-*
  361. # Kconfigs may be included either alphabetically (according to the
  362. # plat- suffix) or along side the corresponding mach-* source.
  363. #
  364. source "arch/arm/mach-actions/Kconfig"
  365. source "arch/arm/mach-alpine/Kconfig"
  366. source "arch/arm/mach-artpec/Kconfig"
  367. source "arch/arm/mach-asm9260/Kconfig"
  368. source "arch/arm/mach-aspeed/Kconfig"
  369. source "arch/arm/mach-at91/Kconfig"
  370. source "arch/arm/mach-axxia/Kconfig"
  371. source "arch/arm/mach-bcm/Kconfig"
  372. source "arch/arm/mach-berlin/Kconfig"
  373. source "arch/arm/mach-clps711x/Kconfig"
  374. source "arch/arm/mach-cns3xxx/Kconfig"
  375. source "arch/arm/mach-davinci/Kconfig"
  376. source "arch/arm/mach-digicolor/Kconfig"
  377. source "arch/arm/mach-dove/Kconfig"
  378. source "arch/arm/mach-ep93xx/Kconfig"
  379. source "arch/arm/mach-exynos/Kconfig"
  380. source "arch/arm/mach-footbridge/Kconfig"
  381. source "arch/arm/mach-gemini/Kconfig"
  382. source "arch/arm/mach-highbank/Kconfig"
  383. source "arch/arm/mach-hisi/Kconfig"
  384. source "arch/arm/mach-hpe/Kconfig"
  385. source "arch/arm/mach-imx/Kconfig"
  386. source "arch/arm/mach-iop32x/Kconfig"
  387. source "arch/arm/mach-ixp4xx/Kconfig"
  388. source "arch/arm/mach-keystone/Kconfig"
  389. source "arch/arm/mach-lpc32xx/Kconfig"
  390. source "arch/arm/mach-mediatek/Kconfig"
  391. source "arch/arm/mach-meson/Kconfig"
  392. source "arch/arm/mach-milbeaut/Kconfig"
  393. source "arch/arm/mach-mmp/Kconfig"
  394. source "arch/arm/mach-moxart/Kconfig"
  395. source "arch/arm/mach-mstar/Kconfig"
  396. source "arch/arm/mach-mv78xx0/Kconfig"
  397. source "arch/arm/mach-mvebu/Kconfig"
  398. source "arch/arm/mach-mxs/Kconfig"
  399. source "arch/arm/mach-nomadik/Kconfig"
  400. source "arch/arm/mach-npcm/Kconfig"
  401. source "arch/arm/mach-nspire/Kconfig"
  402. source "arch/arm/mach-omap1/Kconfig"
  403. source "arch/arm/mach-omap2/Kconfig"
  404. source "arch/arm/mach-orion5x/Kconfig"
  405. source "arch/arm/mach-oxnas/Kconfig"
  406. source "arch/arm/mach-pxa/Kconfig"
  407. source "arch/arm/mach-qcom/Kconfig"
  408. source "arch/arm/mach-rda/Kconfig"
  409. source "arch/arm/mach-realtek/Kconfig"
  410. source "arch/arm/mach-rpc/Kconfig"
  411. source "arch/arm/mach-rockchip/Kconfig"
  412. source "arch/arm/mach-s3c/Kconfig"
  413. source "arch/arm/mach-s5pv210/Kconfig"
  414. source "arch/arm/mach-sa1100/Kconfig"
  415. source "arch/arm/mach-shmobile/Kconfig"
  416. source "arch/arm/mach-socfpga/Kconfig"
  417. source "arch/arm/mach-spear/Kconfig"
  418. source "arch/arm/mach-sti/Kconfig"
  419. source "arch/arm/mach-stm32/Kconfig"
  420. source "arch/arm/mach-sunplus/Kconfig"
  421. source "arch/arm/mach-sunxi/Kconfig"
  422. source "arch/arm/mach-tegra/Kconfig"
  423. source "arch/arm/mach-uniphier/Kconfig"
  424. source "arch/arm/mach-ux500/Kconfig"
  425. source "arch/arm/mach-versatile/Kconfig"
  426. source "arch/arm/mach-vt8500/Kconfig"
  427. source "arch/arm/mach-zynq/Kconfig"
  428. # ARMv7-M architecture
  429. config ARCH_LPC18XX
  430. bool "NXP LPC18xx/LPC43xx"
  431. depends on ARM_SINGLE_ARMV7M
  432. select ARCH_HAS_RESET_CONTROLLER
  433. select ARM_AMBA
  434. select CLKSRC_LPC32XX
  435. select PINCTRL
  436. help
  437. Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
  438. high performance microcontrollers.
  439. config ARCH_MPS2
  440. bool "ARM MPS2 platform"
  441. depends on ARM_SINGLE_ARMV7M
  442. select ARM_AMBA
  443. select CLKSRC_MPS2
  444. help
  445. Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
  446. with a range of available cores like Cortex-M3/M4/M7.
  447. Please, note that depends which Application Note is used memory map
  448. for the platform may vary, so adjustment of RAM base might be needed.
  449. # Definitions to make life easier
  450. config ARCH_ACORN
  451. bool
  452. config PLAT_ORION
  453. bool
  454. select CLKSRC_MMIO
  455. select GENERIC_IRQ_CHIP
  456. select IRQ_DOMAIN
  457. config PLAT_ORION_LEGACY
  458. bool
  459. select PLAT_ORION
  460. config PLAT_VERSATILE
  461. bool
  462. source "arch/arm/mm/Kconfig"
  463. config IWMMXT
  464. bool "Enable iWMMXt support"
  465. depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
  466. default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
  467. help
  468. Enable support for iWMMXt context switching at run time if
  469. running on a CPU that supports it.
  470. if !MMU
  471. source "arch/arm/Kconfig-nommu"
  472. endif
  473. config PJ4B_ERRATA_4742
  474. bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
  475. depends on CPU_PJ4B && MACH_ARMADA_370
  476. default y
  477. help
  478. When coming out of either a Wait for Interrupt (WFI) or a Wait for
  479. Event (WFE) IDLE states, a specific timing sensitivity exists between
  480. the retiring WFI/WFE instructions and the newly issued subsequent
  481. instructions. This sensitivity can result in a CPU hang scenario.
  482. Workaround:
  483. The software must insert either a Data Synchronization Barrier (DSB)
  484. or Data Memory Barrier (DMB) command immediately after the WFI/WFE
  485. instruction
  486. config ARM_ERRATA_326103
  487. bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
  488. depends on CPU_V6
  489. help
  490. Executing a SWP instruction to read-only memory does not set bit 11
  491. of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
  492. treat the access as a read, preventing a COW from occurring and
  493. causing the faulting task to livelock.
  494. config ARM_ERRATA_411920
  495. bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
  496. depends on CPU_V6 || CPU_V6K
  497. help
  498. Invalidation of the Instruction Cache operation can
  499. fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
  500. It does not affect the MPCore. This option enables the ARM Ltd.
  501. recommended workaround.
  502. config ARM_ERRATA_430973
  503. bool "ARM errata: Stale prediction on replaced interworking branch"
  504. depends on CPU_V7
  505. help
  506. This option enables the workaround for the 430973 Cortex-A8
  507. r1p* erratum. If a code sequence containing an ARM/Thumb
  508. interworking branch is replaced with another code sequence at the
  509. same virtual address, whether due to self-modifying code or virtual
  510. to physical address re-mapping, Cortex-A8 does not recover from the
  511. stale interworking branch prediction. This results in Cortex-A8
  512. executing the new code sequence in the incorrect ARM or Thumb state.
  513. The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
  514. and also flushes the branch target cache at every context switch.
  515. Note that setting specific bits in the ACTLR register may not be
  516. available in non-secure mode.
  517. config ARM_ERRATA_458693
  518. bool "ARM errata: Processor deadlock when a false hazard is created"
  519. depends on CPU_V7
  520. depends on !ARCH_MULTIPLATFORM
  521. help
  522. This option enables the workaround for the 458693 Cortex-A8 (r2p0)
  523. erratum. For very specific sequences of memory operations, it is
  524. possible for a hazard condition intended for a cache line to instead
  525. be incorrectly associated with a different cache line. This false
  526. hazard might then cause a processor deadlock. The workaround enables
  527. the L1 caching of the NEON accesses and disables the PLD instruction
  528. in the ACTLR register. Note that setting specific bits in the ACTLR
  529. register may not be available in non-secure mode.
  530. config ARM_ERRATA_460075
  531. bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
  532. depends on CPU_V7
  533. depends on !ARCH_MULTIPLATFORM
  534. help
  535. This option enables the workaround for the 460075 Cortex-A8 (r2p0)
  536. erratum. Any asynchronous access to the L2 cache may encounter a
  537. situation in which recent store transactions to the L2 cache are lost
  538. and overwritten with stale memory contents from external memory. The
  539. workaround disables the write-allocate mode for the L2 cache via the
  540. ACTLR register. Note that setting specific bits in the ACTLR register
  541. may not be available in non-secure mode.
  542. config ARM_ERRATA_742230
  543. bool "ARM errata: DMB operation may be faulty"
  544. depends on CPU_V7 && SMP
  545. depends on !ARCH_MULTIPLATFORM
  546. help
  547. This option enables the workaround for the 742230 Cortex-A9
  548. (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
  549. between two write operations may not ensure the correct visibility
  550. ordering of the two writes. This workaround sets a specific bit in
  551. the diagnostic register of the Cortex-A9 which causes the DMB
  552. instruction to behave as a DSB, ensuring the correct behaviour of
  553. the two writes.
  554. config ARM_ERRATA_742231
  555. bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
  556. depends on CPU_V7 && SMP
  557. depends on !ARCH_MULTIPLATFORM
  558. help
  559. This option enables the workaround for the 742231 Cortex-A9
  560. (r2p0..r2p2) erratum. Under certain conditions, specific to the
  561. Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
  562. accessing some data located in the same cache line, may get corrupted
  563. data due to bad handling of the address hazard when the line gets
  564. replaced from one of the CPUs at the same time as another CPU is
  565. accessing it. This workaround sets specific bits in the diagnostic
  566. register of the Cortex-A9 which reduces the linefill issuing
  567. capabilities of the processor.
  568. config ARM_ERRATA_643719
  569. bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
  570. depends on CPU_V7 && SMP
  571. default y
  572. help
  573. This option enables the workaround for the 643719 Cortex-A9 (prior to
  574. r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
  575. register returns zero when it should return one. The workaround
  576. corrects this value, ensuring cache maintenance operations which use
  577. it behave as intended and avoiding data corruption.
  578. config ARM_ERRATA_720789
  579. bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
  580. depends on CPU_V7
  581. help
  582. This option enables the workaround for the 720789 Cortex-A9 (prior to
  583. r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
  584. broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
  585. As a consequence of this erratum, some TLB entries which should be
  586. invalidated are not, resulting in an incoherency in the system page
  587. tables. The workaround changes the TLB flushing routines to invalidate
  588. entries regardless of the ASID.
  589. config ARM_ERRATA_743622
  590. bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
  591. depends on CPU_V7
  592. depends on !ARCH_MULTIPLATFORM
  593. help
  594. This option enables the workaround for the 743622 Cortex-A9
  595. (r2p*) erratum. Under very rare conditions, a faulty
  596. optimisation in the Cortex-A9 Store Buffer may lead to data
  597. corruption. This workaround sets a specific bit in the diagnostic
  598. register of the Cortex-A9 which disables the Store Buffer
  599. optimisation, preventing the defect from occurring. This has no
  600. visible impact on the overall performance or power consumption of the
  601. processor.
  602. config ARM_ERRATA_751472
  603. bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
  604. depends on CPU_V7
  605. depends on !ARCH_MULTIPLATFORM
  606. help
  607. This option enables the workaround for the 751472 Cortex-A9 (prior
  608. to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
  609. completion of a following broadcasted operation if the second
  610. operation is received by a CPU before the ICIALLUIS has completed,
  611. potentially leading to corrupted entries in the cache or TLB.
  612. config ARM_ERRATA_754322
  613. bool "ARM errata: possible faulty MMU translations following an ASID switch"
  614. depends on CPU_V7
  615. help
  616. This option enables the workaround for the 754322 Cortex-A9 (r2p*,
  617. r3p*) erratum. A speculative memory access may cause a page table walk
  618. which starts prior to an ASID switch but completes afterwards. This
  619. can populate the micro-TLB with a stale entry which may be hit with
  620. the new ASID. This workaround places two dsb instructions in the mm
  621. switching code so that no page table walks can cross the ASID switch.
  622. config ARM_ERRATA_754327
  623. bool "ARM errata: no automatic Store Buffer drain"
  624. depends on CPU_V7 && SMP
  625. help
  626. This option enables the workaround for the 754327 Cortex-A9 (prior to
  627. r2p0) erratum. The Store Buffer does not have any automatic draining
  628. mechanism and therefore a livelock may occur if an external agent
  629. continuously polls a memory location waiting to observe an update.
  630. This workaround defines cpu_relax() as smp_mb(), preventing correctly
  631. written polling loops from denying visibility of updates to memory.
  632. config ARM_ERRATA_364296
  633. bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
  634. depends on CPU_V6
  635. help
  636. This options enables the workaround for the 364296 ARM1136
  637. r0p2 erratum (possible cache data corruption with
  638. hit-under-miss enabled). It sets the undocumented bit 31 in
  639. the auxiliary control register and the FI bit in the control
  640. register, thus disabling hit-under-miss without putting the
  641. processor into full low interrupt latency mode. ARM11MPCore
  642. is not affected.
  643. config ARM_ERRATA_764369
  644. bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
  645. depends on CPU_V7 && SMP
  646. help
  647. This option enables the workaround for erratum 764369
  648. affecting Cortex-A9 MPCore with two or more processors (all
  649. current revisions). Under certain timing circumstances, a data
  650. cache line maintenance operation by MVA targeting an Inner
  651. Shareable memory region may fail to proceed up to either the
  652. Point of Coherency or to the Point of Unification of the
  653. system. This workaround adds a DSB instruction before the
  654. relevant cache maintenance functions and sets a specific bit
  655. in the diagnostic control register of the SCU.
  656. config ARM_ERRATA_764319
  657. bool "ARM errata: Read to DBGPRSR and DBGOSLSR may generate Undefined instruction"
  658. depends on CPU_V7
  659. help
  660. This option enables the workaround for the 764319 Cortex A-9 erratum.
  661. CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
  662. unexpected Undefined Instruction exception when the DBGSWENABLE
  663. external pin is set to 0, even when the CP14 accesses are performed
  664. from a privileged mode. This work around catches the exception in a
  665. way the kernel does not stop execution.
  666. config ARM_ERRATA_775420
  667. bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
  668. depends on CPU_V7
  669. help
  670. This option enables the workaround for the 775420 Cortex-A9 (r2p2,
  671. r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
  672. operation aborts with MMU exception, it might cause the processor
  673. to deadlock. This workaround puts DSB before executing ISB if
  674. an abort may occur on cache maintenance.
  675. config ARM_ERRATA_798181
  676. bool "ARM errata: TLBI/DSB failure on Cortex-A15"
  677. depends on CPU_V7 && SMP
  678. help
  679. On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
  680. adequately shooting down all use of the old entries. This
  681. option enables the Linux kernel workaround for this erratum
  682. which sends an IPI to the CPUs that are running the same ASID
  683. as the one being invalidated.
  684. config ARM_ERRATA_773022
  685. bool "ARM errata: incorrect instructions may be executed from loop buffer"
  686. depends on CPU_V7
  687. help
  688. This option enables the workaround for the 773022 Cortex-A15
  689. (up to r0p4) erratum. In certain rare sequences of code, the
  690. loop buffer may deliver incorrect instructions. This
  691. workaround disables the loop buffer to avoid the erratum.
  692. config ARM_ERRATA_818325_852422
  693. bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
  694. depends on CPU_V7
  695. help
  696. This option enables the workaround for:
  697. - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
  698. instruction might deadlock. Fixed in r0p1.
  699. - Cortex-A12 852422: Execution of a sequence of instructions might
  700. lead to either a data corruption or a CPU deadlock. Not fixed in
  701. any Cortex-A12 cores yet.
  702. This workaround for all both errata involves setting bit[12] of the
  703. Feature Register. This bit disables an optimisation applied to a
  704. sequence of 2 instructions that use opposing condition codes.
  705. config ARM_ERRATA_821420
  706. bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
  707. depends on CPU_V7
  708. help
  709. This option enables the workaround for the 821420 Cortex-A12
  710. (all revs) erratum. In very rare timing conditions, a sequence
  711. of VMOV to Core registers instructions, for which the second
  712. one is in the shadow of a branch or abort, can lead to a
  713. deadlock when the VMOV instructions are issued out-of-order.
  714. config ARM_ERRATA_825619
  715. bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
  716. depends on CPU_V7
  717. help
  718. This option enables the workaround for the 825619 Cortex-A12
  719. (all revs) erratum. Within rare timing constraints, executing a
  720. DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
  721. and Device/Strongly-Ordered loads and stores might cause deadlock
  722. config ARM_ERRATA_857271
  723. bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
  724. depends on CPU_V7
  725. help
  726. This option enables the workaround for the 857271 Cortex-A12
  727. (all revs) erratum. Under very rare timing conditions, the CPU might
  728. hang. The workaround is expected to have a < 1% performance impact.
  729. config ARM_ERRATA_852421
  730. bool "ARM errata: A17: DMB ST might fail to create order between stores"
  731. depends on CPU_V7
  732. help
  733. This option enables the workaround for the 852421 Cortex-A17
  734. (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
  735. execution of a DMB ST instruction might fail to properly order
  736. stores from GroupA and stores from GroupB.
  737. config ARM_ERRATA_852423
  738. bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
  739. depends on CPU_V7
  740. help
  741. This option enables the workaround for:
  742. - Cortex-A17 852423: Execution of a sequence of instructions might
  743. lead to either a data corruption or a CPU deadlock. Not fixed in
  744. any Cortex-A17 cores yet.
  745. This is identical to Cortex-A12 erratum 852422. It is a separate
  746. config option from the A12 erratum due to the way errata are checked
  747. for and handled.
  748. config ARM_ERRATA_857272
  749. bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
  750. depends on CPU_V7
  751. help
  752. This option enables the workaround for the 857272 Cortex-A17 erratum.
  753. This erratum is not known to be fixed in any A17 revision.
  754. This is identical to Cortex-A12 erratum 857271. It is a separate
  755. config option from the A12 erratum due to the way errata are checked
  756. for and handled.
  757. endmenu
  758. source "arch/arm/common/Kconfig"
  759. menu "Bus support"
  760. config ISA
  761. bool
  762. help
  763. Find out whether you have ISA slots on your motherboard. ISA is the
  764. name of a bus system, i.e. the way the CPU talks to the other stuff
  765. inside your box. Other bus systems are PCI, EISA, MicroChannel
  766. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  767. newer boards don't support it. If you have ISA, say Y, otherwise N.
  768. # Select ISA DMA interface
  769. config ISA_DMA_API
  770. bool
  771. config PCI_NANOENGINE
  772. bool "BSE nanoEngine PCI support"
  773. depends on SA1100_NANOENGINE
  774. help
  775. Enable PCI on the BSE nanoEngine board.
  776. config ARM_ERRATA_814220
  777. bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
  778. depends on CPU_V7
  779. help
  780. The v7 ARM states that all cache and branch predictor maintenance
  781. operations that do not specify an address execute, relative to
  782. each other, in program order.
  783. However, because of this erratum, an L2 set/way cache maintenance
  784. operation can overtake an L1 set/way cache maintenance operation.
  785. This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
  786. r0p4, r0p5.
  787. endmenu
  788. menu "Kernel Features"
  789. config HAVE_SMP
  790. bool
  791. help
  792. This option should be selected by machines which have an SMP-
  793. capable CPU.
  794. The only effect of this option is to make the SMP-related
  795. options available to the user for configuration.
  796. config SMP
  797. bool "Symmetric Multi-Processing"
  798. depends on CPU_V6K || CPU_V7
  799. depends on HAVE_SMP
  800. depends on MMU || ARM_MPU
  801. select IRQ_WORK
  802. help
  803. This enables support for systems with more than one CPU. If you have
  804. a system with only one CPU, say N. If you have a system with more
  805. than one CPU, say Y.
  806. If you say N here, the kernel will run on uni- and multiprocessor
  807. machines, but will use only one CPU of a multiprocessor machine. If
  808. you say Y here, the kernel will run on many, but not all,
  809. uniprocessor machines. On a uniprocessor machine, the kernel
  810. will run faster if you say N here.
  811. See also <file:Documentation/x86/i386/IO-APIC.rst>,
  812. <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
  813. <http://tldp.org/HOWTO/SMP-HOWTO.html>.
  814. If you don't know what to do here, say N.
  815. config SMP_ON_UP
  816. bool "Allow booting SMP kernel on uniprocessor systems"
  817. depends on SMP && MMU
  818. default y
  819. help
  820. SMP kernels contain instructions which fail on non-SMP processors.
  821. Enabling this option allows the kernel to modify itself to make
  822. these instructions safe. Disabling it allows about 1K of space
  823. savings.
  824. If you don't know what to do here, say Y.
  825. config CURRENT_POINTER_IN_TPIDRURO
  826. def_bool y
  827. depends on CPU_32v6K && !CPU_V6
  828. config IRQSTACKS
  829. def_bool y
  830. select HAVE_IRQ_EXIT_ON_IRQ_STACK
  831. select HAVE_SOFTIRQ_ON_OWN_STACK
  832. config ARM_CPU_TOPOLOGY
  833. bool "Support cpu topology definition"
  834. depends on SMP && CPU_V7
  835. default y
  836. help
  837. Support ARM cpu topology definition. The MPIDR register defines
  838. affinity between processors which is then used to describe the cpu
  839. topology of an ARM System.
  840. config SCHED_MC
  841. bool "Multi-core scheduler support"
  842. depends on ARM_CPU_TOPOLOGY
  843. help
  844. Multi-core scheduler support improves the CPU scheduler's decision
  845. making when dealing with multi-core CPU chips at a cost of slightly
  846. increased overhead in some places. If unsure say N here.
  847. config SCHED_SMT
  848. bool "SMT scheduler support"
  849. depends on ARM_CPU_TOPOLOGY
  850. help
  851. Improves the CPU scheduler's decision making when dealing with
  852. MultiThreading at a cost of slightly increased overhead in some
  853. places. If unsure say N here.
  854. config HAVE_ARM_SCU
  855. bool
  856. help
  857. This option enables support for the ARM snoop control unit
  858. config HAVE_ARM_ARCH_TIMER
  859. bool "Architected timer support"
  860. depends on CPU_V7
  861. select ARM_ARCH_TIMER
  862. help
  863. This option enables support for the ARM architected timer
  864. config HAVE_ARM_TWD
  865. bool
  866. help
  867. This options enables support for the ARM timer and watchdog unit
  868. config MCPM
  869. bool "Multi-Cluster Power Management"
  870. depends on CPU_V7 && SMP
  871. help
  872. This option provides the common power management infrastructure
  873. for (multi-)cluster based systems, such as big.LITTLE based
  874. systems.
  875. config MCPM_QUAD_CLUSTER
  876. bool
  877. depends on MCPM
  878. help
  879. To avoid wasting resources unnecessarily, MCPM only supports up
  880. to 2 clusters by default.
  881. Platforms with 3 or 4 clusters that use MCPM must select this
  882. option to allow the additional clusters to be managed.
  883. config BIG_LITTLE
  884. bool "big.LITTLE support (Experimental)"
  885. depends on CPU_V7 && SMP
  886. select MCPM
  887. help
  888. This option enables support selections for the big.LITTLE
  889. system architecture.
  890. config BL_SWITCHER
  891. bool "big.LITTLE switcher support"
  892. depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
  893. select CPU_PM
  894. help
  895. The big.LITTLE "switcher" provides the core functionality to
  896. transparently handle transition between a cluster of A15's
  897. and a cluster of A7's in a big.LITTLE system.
  898. config BL_SWITCHER_DUMMY_IF
  899. tristate "Simple big.LITTLE switcher user interface"
  900. depends on BL_SWITCHER && DEBUG_KERNEL
  901. help
  902. This is a simple and dummy char dev interface to control
  903. the big.LITTLE switcher core code. It is meant for
  904. debugging purposes only.
  905. choice
  906. prompt "Memory split"
  907. depends on MMU
  908. default VMSPLIT_3G
  909. help
  910. Select the desired split between kernel and user memory.
  911. If you are not absolutely sure what you are doing, leave this
  912. option alone!
  913. config VMSPLIT_3G
  914. bool "3G/1G user/kernel split"
  915. config VMSPLIT_3G_OPT
  916. depends on !ARM_LPAE
  917. bool "3G/1G user/kernel split (for full 1G low memory)"
  918. config VMSPLIT_2G
  919. bool "2G/2G user/kernel split"
  920. config VMSPLIT_1G
  921. bool "1G/3G user/kernel split"
  922. endchoice
  923. config PAGE_OFFSET
  924. hex
  925. default PHYS_OFFSET if !MMU
  926. default 0x40000000 if VMSPLIT_1G
  927. default 0x80000000 if VMSPLIT_2G
  928. default 0xB0000000 if VMSPLIT_3G_OPT
  929. default 0xC0000000
  930. config KASAN_SHADOW_OFFSET
  931. hex
  932. depends on KASAN
  933. default 0x1f000000 if PAGE_OFFSET=0x40000000
  934. default 0x5f000000 if PAGE_OFFSET=0x80000000
  935. default 0x9f000000 if PAGE_OFFSET=0xC0000000
  936. default 0x8f000000 if PAGE_OFFSET=0xB0000000
  937. default 0xffffffff
  938. config NR_CPUS
  939. int "Maximum number of CPUs (2-32)"
  940. range 2 16 if DEBUG_KMAP_LOCAL
  941. range 2 32 if !DEBUG_KMAP_LOCAL
  942. depends on SMP
  943. default "4"
  944. help
  945. The maximum number of CPUs that the kernel can support.
  946. Up to 32 CPUs can be supported, or up to 16 if kmap_local()
  947. debugging is enabled, which uses half of the per-CPU fixmap
  948. slots as guard regions.
  949. config HOTPLUG_CPU
  950. bool "Support for hot-pluggable CPUs"
  951. depends on SMP
  952. select GENERIC_IRQ_MIGRATION
  953. help
  954. Say Y here to experiment with turning CPUs off and on. CPUs
  955. can be controlled through /sys/devices/system/cpu.
  956. config ARM_PSCI
  957. bool "Support for the ARM Power State Coordination Interface (PSCI)"
  958. depends on HAVE_ARM_SMCCC
  959. select ARM_PSCI_FW
  960. help
  961. Say Y here if you want Linux to communicate with system firmware
  962. implementing the PSCI specification for CPU-centric power
  963. management operations described in ARM document number ARM DEN
  964. 0022A ("Power State Coordination Interface System Software on
  965. ARM processors").
  966. # The GPIO number here must be sorted by descending number. In case of
  967. # a multiplatform kernel, we just want the highest value required by the
  968. # selected platforms.
  969. config ARCH_NR_GPIO
  970. int
  971. default 2048 if ARCH_INTEL_SOCFPGA
  972. default 1024 if ARCH_BRCMSTB || ARCH_RENESAS || ARCH_TEGRA || \
  973. ARCH_ZYNQ || ARCH_ASPEED
  974. default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \
  975. SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210
  976. default 416 if ARCH_SUNXI
  977. default 392 if ARCH_U8500
  978. default 352 if ARCH_VT8500
  979. default 288 if ARCH_ROCKCHIP
  980. default 264 if MACH_H4700
  981. default 0
  982. help
  983. Maximum number of GPIOs in the system.
  984. If unsure, leave the default value.
  985. config HZ_FIXED
  986. int
  987. default 128 if SOC_AT91RM9200
  988. default 0
  989. choice
  990. depends on HZ_FIXED = 0
  991. prompt "Timer frequency"
  992. config HZ_100
  993. bool "100 Hz"
  994. config HZ_200
  995. bool "200 Hz"
  996. config HZ_250
  997. bool "250 Hz"
  998. config HZ_300
  999. bool "300 Hz"
  1000. config HZ_500
  1001. bool "500 Hz"
  1002. config HZ_1000
  1003. bool "1000 Hz"
  1004. endchoice
  1005. config HZ
  1006. int
  1007. default HZ_FIXED if HZ_FIXED != 0
  1008. default 100 if HZ_100
  1009. default 200 if HZ_200
  1010. default 250 if HZ_250
  1011. default 300 if HZ_300
  1012. default 500 if HZ_500
  1013. default 1000
  1014. config SCHED_HRTICK
  1015. def_bool HIGH_RES_TIMERS
  1016. config THUMB2_KERNEL
  1017. bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
  1018. depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
  1019. default y if CPU_THUMBONLY
  1020. select ARM_UNWIND
  1021. help
  1022. By enabling this option, the kernel will be compiled in
  1023. Thumb-2 mode.
  1024. If unsure, say N.
  1025. config ARM_PATCH_IDIV
  1026. bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
  1027. depends on CPU_32v7
  1028. default y
  1029. help
  1030. The ARM compiler inserts calls to __aeabi_idiv() and
  1031. __aeabi_uidiv() when it needs to perform division on signed
  1032. and unsigned integers. Some v7 CPUs have support for the sdiv
  1033. and udiv instructions that can be used to implement those
  1034. functions.
  1035. Enabling this option allows the kernel to modify itself to
  1036. replace the first two instructions of these library functions
  1037. with the sdiv or udiv plus "bx lr" instructions when the CPU
  1038. it is running on supports them. Typically this will be faster
  1039. and less power intensive than running the original library
  1040. code to do integer division.
  1041. config AEABI
  1042. bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
  1043. !CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
  1044. default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
  1045. help
  1046. This option allows for the kernel to be compiled using the latest
  1047. ARM ABI (aka EABI). This is only useful if you are using a user
  1048. space environment that is also compiled with EABI.
  1049. Since there are major incompatibilities between the legacy ABI and
  1050. EABI, especially with regard to structure member alignment, this
  1051. option also changes the kernel syscall calling convention to
  1052. disambiguate both ABIs and allow for backward compatibility support
  1053. (selected with CONFIG_OABI_COMPAT).
  1054. To use this you need GCC version 4.0.0 or later.
  1055. config OABI_COMPAT
  1056. bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
  1057. depends on AEABI && !THUMB2_KERNEL
  1058. help
  1059. This option preserves the old syscall interface along with the
  1060. new (ARM EABI) one. It also provides a compatibility layer to
  1061. intercept syscalls that have structure arguments which layout
  1062. in memory differs between the legacy ABI and the new ARM EABI
  1063. (only for non "thumb" binaries). This option adds a tiny
  1064. overhead to all syscalls and produces a slightly larger kernel.
  1065. The seccomp filter system will not be available when this is
  1066. selected, since there is no way yet to sensibly distinguish
  1067. between calling conventions during filtering.
  1068. If you know you'll be using only pure EABI user space then you
  1069. can say N here. If this option is not selected and you attempt
  1070. to execute a legacy ABI binary then the result will be
  1071. UNPREDICTABLE (in fact it can be predicted that it won't work
  1072. at all). If in doubt say N.
  1073. config ARCH_SELECT_MEMORY_MODEL
  1074. def_bool y
  1075. config ARCH_FLATMEM_ENABLE
  1076. def_bool !(ARCH_RPC || ARCH_SA1100)
  1077. config ARCH_SPARSEMEM_ENABLE
  1078. def_bool !ARCH_FOOTBRIDGE
  1079. select SPARSEMEM_STATIC if SPARSEMEM
  1080. config HIGHMEM
  1081. bool "High Memory Support"
  1082. depends on MMU
  1083. select KMAP_LOCAL
  1084. select KMAP_LOCAL_NON_LINEAR_PTE_ARRAY
  1085. help
  1086. The address space of ARM processors is only 4 Gigabytes large
  1087. and it has to accommodate user address space, kernel address
  1088. space as well as some memory mapped IO. That means that, if you
  1089. have a large amount of physical memory and/or IO, not all of the
  1090. memory can be "permanently mapped" by the kernel. The physical
  1091. memory that is not permanently mapped is called "high memory".
  1092. Depending on the selected kernel/user memory split, minimum
  1093. vmalloc space and actual amount of RAM, you may not need this
  1094. option which should result in a slightly faster kernel.
  1095. If unsure, say n.
  1096. config HIGHPTE
  1097. bool "Allocate 2nd-level pagetables from highmem" if EXPERT
  1098. depends on HIGHMEM
  1099. default y
  1100. help
  1101. The VM uses one page of physical memory for each page table.
  1102. For systems with a lot of processes, this can use a lot of
  1103. precious low memory, eventually leading to low memory being
  1104. consumed by page tables. Setting this option will allow
  1105. user-space 2nd level page tables to reside in high memory.
  1106. config CPU_SW_DOMAIN_PAN
  1107. bool "Enable use of CPU domains to implement privileged no-access"
  1108. depends on MMU && !ARM_LPAE
  1109. default y
  1110. help
  1111. Increase kernel security by ensuring that normal kernel accesses
  1112. are unable to access userspace addresses. This can help prevent
  1113. use-after-free bugs becoming an exploitable privilege escalation
  1114. by ensuring that magic values (such as LIST_POISON) will always
  1115. fault when dereferenced.
  1116. CPUs with low-vector mappings use a best-efforts implementation.
  1117. Their lower 1MB needs to remain accessible for the vectors, but
  1118. the remainder of userspace will become appropriately inaccessible.
  1119. config HW_PERF_EVENTS
  1120. def_bool y
  1121. depends on ARM_PMU
  1122. config ARM_MODULE_PLTS
  1123. bool "Use PLTs to allow module memory to spill over into vmalloc area"
  1124. depends on MODULES
  1125. select KASAN_VMALLOC if KASAN
  1126. default y
  1127. help
  1128. Allocate PLTs when loading modules so that jumps and calls whose
  1129. targets are too far away for their relative offsets to be encoded
  1130. in the instructions themselves can be bounced via veneers in the
  1131. module's PLT. This allows modules to be allocated in the generic
  1132. vmalloc area after the dedicated module memory area has been
  1133. exhausted. The modules will use slightly more memory, but after
  1134. rounding up to page size, the actual memory footprint is usually
  1135. the same.
  1136. Disabling this is usually safe for small single-platform
  1137. configurations. If unsure, say y.
  1138. config ARCH_FORCE_MAX_ORDER
  1139. int "Maximum zone order"
  1140. default "12" if SOC_AM33XX
  1141. default "9" if SA1111
  1142. default "11"
  1143. help
  1144. The kernel memory allocator divides physically contiguous memory
  1145. blocks into "zones", where each zone is a power of two number of
  1146. pages. This option selects the largest power of two that the kernel
  1147. keeps in the memory allocator. If you need to allocate very large
  1148. blocks of physically contiguous memory, then you may need to
  1149. increase this value.
  1150. This config option is actually maximum order plus one. For example,
  1151. a value of 11 means that the largest free memory block is 2^10 pages.
  1152. config ALIGNMENT_TRAP
  1153. def_bool CPU_CP15_MMU
  1154. select HAVE_PROC_CPU if PROC_FS
  1155. help
  1156. ARM processors cannot fetch/store information which is not
  1157. naturally aligned on the bus, i.e., a 4 byte fetch must start at an
  1158. address divisible by 4. On 32-bit ARM processors, these non-aligned
  1159. fetch/store instructions will be emulated in software if you say
  1160. here, which has a severe performance impact. This is necessary for
  1161. correct operation of some network protocols. With an IP-only
  1162. configuration it is safe to say N, otherwise say Y.
  1163. config UACCESS_WITH_MEMCPY
  1164. bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
  1165. depends on MMU
  1166. default y if CPU_FEROCEON
  1167. help
  1168. Implement faster copy_to_user and clear_user methods for CPU
  1169. cores where a 8-word STM instruction give significantly higher
  1170. memory write throughput than a sequence of individual 32bit stores.
  1171. A possible side effect is a slight increase in scheduling latency
  1172. between threads sharing the same address space if they invoke
  1173. such copy operations with large buffers.
  1174. However, if the CPU data cache is using a write-allocate mode,
  1175. this option is unlikely to provide any performance gain.
  1176. config PARAVIRT
  1177. bool "Enable paravirtualization code"
  1178. help
  1179. This changes the kernel so it can modify itself when it is run
  1180. under a hypervisor, potentially improving performance significantly
  1181. over full virtualization.
  1182. config PARAVIRT_TIME_ACCOUNTING
  1183. bool "Paravirtual steal time accounting"
  1184. select PARAVIRT
  1185. help
  1186. Select this option to enable fine granularity task steal time
  1187. accounting. Time spent executing other tasks in parallel with
  1188. the current vCPU is discounted from the vCPU power. To account for
  1189. that, there can be a small performance impact.
  1190. If in doubt, say N here.
  1191. config XEN_DOM0
  1192. def_bool y
  1193. depends on XEN
  1194. config XEN
  1195. bool "Xen guest support on ARM"
  1196. depends on ARM && AEABI && OF
  1197. depends on CPU_V7 && !CPU_V6
  1198. depends on !GENERIC_ATOMIC64
  1199. depends on MMU
  1200. select ARCH_DMA_ADDR_T_64BIT
  1201. select ARM_PSCI
  1202. select SWIOTLB
  1203. select SWIOTLB_XEN
  1204. select PARAVIRT
  1205. help
  1206. Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
  1207. config CC_HAVE_STACKPROTECTOR_TLS
  1208. def_bool $(cc-option,-mtp=cp15 -mstack-protector-guard=tls -mstack-protector-guard-offset=0)
  1209. config STACKPROTECTOR_PER_TASK
  1210. bool "Use a unique stack canary value for each task"
  1211. depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA
  1212. depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS
  1213. select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS
  1214. default y
  1215. help
  1216. Due to the fact that GCC uses an ordinary symbol reference from
  1217. which to load the value of the stack canary, this value can only
  1218. change at reboot time on SMP systems, and all tasks running in the
  1219. kernel's address space are forced to use the same canary value for
  1220. the entire duration that the system is up.
  1221. Enable this option to switch to a different method that uses a
  1222. different canary value for each task.
  1223. endmenu
  1224. menu "Boot options"
  1225. config USE_OF
  1226. bool "Flattened Device Tree support"
  1227. select IRQ_DOMAIN
  1228. select OF
  1229. help
  1230. Include support for flattened device tree machine descriptions.
  1231. config ATAGS
  1232. bool "Support for the traditional ATAGS boot data passing"
  1233. default y
  1234. help
  1235. This is the traditional way of passing data to the kernel at boot
  1236. time. If you are solely relying on the flattened device tree (or
  1237. the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
  1238. to remove ATAGS support from your kernel binary.
  1239. config UNUSED_BOARD_FILES
  1240. bool "Board support for machines without known users"
  1241. depends on ATAGS
  1242. help
  1243. Most ATAGS based board files are completely unused and are
  1244. scheduled for removal in early 2023, and left out of kernels
  1245. by default now. If you are using a board file that is marked
  1246. as unused, turn on this option to build support into the kernel.
  1247. To keep support for your individual board from being removed,
  1248. send a reply to the email discussion at
  1249. https://lore.kernel.org/all/CAK8P3a0Z9vGEQbVRBo84bSyPFM-LF+hs5w8ZA51g2Z+NsdtDQA@mail.gmail.com/
  1250. config DEPRECATED_PARAM_STRUCT
  1251. bool "Provide old way to pass kernel parameters"
  1252. depends on ATAGS
  1253. help
  1254. This was deprecated in 2001 and announced to live on for 5 years.
  1255. Some old boot loaders still use this way.
  1256. # Compressed boot loader in ROM. Yes, we really want to ask about
  1257. # TEXT and BSS so we preserve their values in the config files.
  1258. config ZBOOT_ROM_TEXT
  1259. hex "Compressed ROM boot loader base address"
  1260. default 0x0
  1261. help
  1262. The physical address at which the ROM-able zImage is to be
  1263. placed in the target. Platforms which normally make use of
  1264. ROM-able zImage formats normally set this to a suitable
  1265. value in their defconfig file.
  1266. If ZBOOT_ROM is not enabled, this has no effect.
  1267. config ZBOOT_ROM_BSS
  1268. hex "Compressed ROM boot loader BSS address"
  1269. default 0x0
  1270. help
  1271. The base address of an area of read/write memory in the target
  1272. for the ROM-able zImage which must be available while the
  1273. decompressor is running. It must be large enough to hold the
  1274. entire decompressed kernel plus an additional 128 KiB.
  1275. Platforms which normally make use of ROM-able zImage formats
  1276. normally set this to a suitable value in their defconfig file.
  1277. If ZBOOT_ROM is not enabled, this has no effect.
  1278. config ZBOOT_ROM
  1279. bool "Compressed boot loader in ROM/flash"
  1280. depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
  1281. depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
  1282. help
  1283. Say Y here if you intend to execute your compressed kernel image
  1284. (zImage) directly from ROM or flash. If unsure, say N.
  1285. config ARM_APPENDED_DTB
  1286. bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
  1287. depends on OF
  1288. help
  1289. With this option, the boot code will look for a device tree binary
  1290. (DTB) appended to zImage
  1291. (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
  1292. This is meant as a backward compatibility convenience for those
  1293. systems with a bootloader that can't be upgraded to accommodate
  1294. the documented boot protocol using a device tree.
  1295. Beware that there is very little in terms of protection against
  1296. this option being confused by leftover garbage in memory that might
  1297. look like a DTB header after a reboot if no actual DTB is appended
  1298. to zImage. Do not leave this option active in a production kernel
  1299. if you don't intend to always append a DTB. Proper passing of the
  1300. location into r2 of a bootloader provided DTB is always preferable
  1301. to this option.
  1302. config ARM_ATAG_DTB_COMPAT
  1303. bool "Supplement the appended DTB with traditional ATAG information"
  1304. depends on ARM_APPENDED_DTB
  1305. help
  1306. Some old bootloaders can't be updated to a DTB capable one, yet
  1307. they provide ATAGs with memory configuration, the ramdisk address,
  1308. the kernel cmdline string, etc. Such information is dynamically
  1309. provided by the bootloader and can't always be stored in a static
  1310. DTB. To allow a device tree enabled kernel to be used with such
  1311. bootloaders, this option allows zImage to extract the information
  1312. from the ATAG list and store it at run time into the appended DTB.
  1313. choice
  1314. prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
  1315. default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
  1316. config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
  1317. bool "Use bootloader kernel arguments if available"
  1318. help
  1319. Uses the command-line options passed by the boot loader instead of
  1320. the device tree bootargs property. If the boot loader doesn't provide
  1321. any, the device tree bootargs property will be used.
  1322. config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
  1323. bool "Extend with bootloader kernel arguments"
  1324. help
  1325. The command-line arguments provided by the boot loader will be
  1326. appended to the the device tree bootargs property.
  1327. endchoice
  1328. config CMDLINE
  1329. string "Default kernel command string"
  1330. default ""
  1331. help
  1332. On some architectures (e.g. CATS), there is currently no way
  1333. for the boot loader to pass arguments to the kernel. For these
  1334. architectures, you should supply some command-line options at build
  1335. time by entering them here. As a minimum, you should specify the
  1336. memory size and the root device (e.g., mem=64M root=/dev/nfs).
  1337. choice
  1338. prompt "Kernel command line type" if CMDLINE != ""
  1339. default CMDLINE_FROM_BOOTLOADER
  1340. config CMDLINE_FROM_BOOTLOADER
  1341. bool "Use bootloader kernel arguments if available"
  1342. help
  1343. Uses the command-line options passed by the boot loader. If
  1344. the boot loader doesn't provide any, the default kernel command
  1345. string provided in CMDLINE will be used.
  1346. config CMDLINE_EXTEND
  1347. bool "Extend bootloader kernel arguments"
  1348. help
  1349. The command-line arguments provided by the boot loader will be
  1350. appended to the default kernel command string.
  1351. config CMDLINE_FORCE
  1352. bool "Always use the default kernel command string"
  1353. help
  1354. Always use the default kernel command string, even if the boot
  1355. loader passes other arguments to the kernel.
  1356. This is useful if you cannot or don't want to change the
  1357. command-line options your boot loader passes to the kernel.
  1358. endchoice
  1359. config XIP_KERNEL
  1360. bool "Kernel Execute-In-Place from ROM"
  1361. depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
  1362. depends on !ARM_PATCH_IDIV && !ARM_PATCH_PHYS_VIRT && !SMP_ON_UP
  1363. help
  1364. Execute-In-Place allows the kernel to run from non-volatile storage
  1365. directly addressable by the CPU, such as NOR flash. This saves RAM
  1366. space since the text section of the kernel is not loaded from flash
  1367. to RAM. Read-write sections, such as the data section and stack,
  1368. are still copied to RAM. The XIP kernel is not compressed since
  1369. it has to run directly from flash, so it will take more space to
  1370. store it. The flash address used to link the kernel object files,
  1371. and for storing it, is configuration dependent. Therefore, if you
  1372. say Y here, you must know the proper physical address where to
  1373. store the kernel image depending on your own flash memory usage.
  1374. Also note that the make target becomes "make xipImage" rather than
  1375. "make zImage" or "make Image". The final kernel binary to put in
  1376. ROM memory will be arch/arm/boot/xipImage.
  1377. If unsure, say N.
  1378. config XIP_PHYS_ADDR
  1379. hex "XIP Kernel Physical Location"
  1380. depends on XIP_KERNEL
  1381. default "0x00080000"
  1382. help
  1383. This is the physical address in your flash memory the kernel will
  1384. be linked for and stored to. This address is dependent on your
  1385. own flash usage.
  1386. config XIP_DEFLATED_DATA
  1387. bool "Store kernel .data section compressed in ROM"
  1388. depends on XIP_KERNEL
  1389. select ZLIB_INFLATE
  1390. help
  1391. Before the kernel is actually executed, its .data section has to be
  1392. copied to RAM from ROM. This option allows for storing that data
  1393. in compressed form and decompressed to RAM rather than merely being
  1394. copied, saving some precious ROM space. A possible drawback is a
  1395. slightly longer boot delay.
  1396. config KEXEC
  1397. bool "Kexec system call (EXPERIMENTAL)"
  1398. depends on (!SMP || PM_SLEEP_SMP)
  1399. depends on MMU
  1400. select KEXEC_CORE
  1401. help
  1402. kexec is a system call that implements the ability to shutdown your
  1403. current kernel, and to start another kernel. It is like a reboot
  1404. but it is independent of the system firmware. And like a reboot
  1405. you can start any kernel with it, not just Linux.
  1406. It is an ongoing process to be certain the hardware in a machine
  1407. is properly shutdown, so do not be surprised if this code does not
  1408. initially work for you.
  1409. config ATAGS_PROC
  1410. bool "Export atags in procfs"
  1411. depends on ATAGS && KEXEC
  1412. default y
  1413. help
  1414. Should the atags used to boot the kernel be exported in an "atags"
  1415. file in procfs. Useful with kexec.
  1416. config CRASH_DUMP
  1417. bool "Build kdump crash kernel (EXPERIMENTAL)"
  1418. help
  1419. Generate crash dump after being started by kexec. This should
  1420. be normally only set in special crash dump kernels which are
  1421. loaded in the main kernel with kexec-tools into a specially
  1422. reserved region and then later executed after a crash by
  1423. kdump/kexec. The crash dump kernel must be compiled to a
  1424. memory address not used by the main kernel
  1425. For more details see Documentation/admin-guide/kdump/kdump.rst
  1426. config AUTO_ZRELADDR
  1427. bool "Auto calculation of the decompressed kernel image address" if !ARCH_MULTIPLATFORM
  1428. default !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
  1429. help
  1430. ZRELADDR is the physical address where the decompressed kernel
  1431. image will be placed. If AUTO_ZRELADDR is selected, the address
  1432. will be determined at run-time, either by masking the current IP
  1433. with 0xf8000000, or, if invalid, from the DTB passed in r2.
  1434. This assumes the zImage being placed in the first 128MB from
  1435. start of memory.
  1436. config EFI_STUB
  1437. bool
  1438. config EFI
  1439. bool "UEFI runtime support"
  1440. depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
  1441. select UCS2_STRING
  1442. select EFI_PARAMS_FROM_FDT
  1443. select EFI_STUB
  1444. select EFI_GENERIC_STUB
  1445. select EFI_RUNTIME_WRAPPERS
  1446. help
  1447. This option provides support for runtime services provided
  1448. by UEFI firmware (such as non-volatile variables, realtime
  1449. clock, and platform reset). A UEFI stub is also provided to
  1450. allow the kernel to be booted as an EFI application. This
  1451. is only useful for kernels that may run on systems that have
  1452. UEFI firmware.
  1453. config DMI
  1454. bool "Enable support for SMBIOS (DMI) tables"
  1455. depends on EFI
  1456. default y
  1457. help
  1458. This enables SMBIOS/DMI feature for systems.
  1459. This option is only useful on systems that have UEFI firmware.
  1460. However, even with this option, the resultant kernel should
  1461. continue to boot on existing non-UEFI platforms.
  1462. NOTE: This does *NOT* enable or encourage the use of DMI quirks,
  1463. i.e., the the practice of identifying the platform via DMI to
  1464. decide whether certain workarounds for buggy hardware and/or
  1465. firmware need to be enabled. This would require the DMI subsystem
  1466. to be enabled much earlier than we do on ARM, which is non-trivial.
  1467. endmenu
  1468. menu "CPU Power Management"
  1469. source "drivers/cpufreq/Kconfig"
  1470. source "drivers/cpuidle/Kconfig"
  1471. endmenu
  1472. menu "Floating point emulation"
  1473. comment "At least one emulation must be selected"
  1474. config FPE_NWFPE
  1475. bool "NWFPE math emulation"
  1476. depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
  1477. help
  1478. Say Y to include the NWFPE floating point emulator in the kernel.
  1479. This is necessary to run most binaries. Linux does not currently
  1480. support floating point hardware so you need to say Y here even if
  1481. your machine has an FPA or floating point co-processor podule.
  1482. You may say N here if you are going to load the Acorn FPEmulator
  1483. early in the bootup.
  1484. config FPE_NWFPE_XP
  1485. bool "Support extended precision"
  1486. depends on FPE_NWFPE
  1487. help
  1488. Say Y to include 80-bit support in the kernel floating-point
  1489. emulator. Otherwise, only 32 and 64-bit support is compiled in.
  1490. Note that gcc does not generate 80-bit operations by default,
  1491. so in most cases this option only enlarges the size of the
  1492. floating point emulator without any good reason.
  1493. You almost surely want to say N here.
  1494. config FPE_FASTFPE
  1495. bool "FastFPE math emulation (EXPERIMENTAL)"
  1496. depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
  1497. help
  1498. Say Y here to include the FAST floating point emulator in the kernel.
  1499. This is an experimental much faster emulator which now also has full
  1500. precision for the mantissa. It does not support any exceptions.
  1501. It is very simple, and approximately 3-6 times faster than NWFPE.
  1502. It should be sufficient for most programs. It may be not suitable
  1503. for scientific calculations, but you have to check this for yourself.
  1504. If you do not feel you need a faster FP emulation you should better
  1505. choose NWFPE.
  1506. config VFP
  1507. bool "VFP-format floating point maths"
  1508. depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
  1509. help
  1510. Say Y to include VFP support code in the kernel. This is needed
  1511. if your hardware includes a VFP unit.
  1512. Please see <file:Documentation/arm/vfp/release-notes.rst> for
  1513. release notes and additional status information.
  1514. Say N if your target does not have VFP hardware.
  1515. config VFPv3
  1516. bool
  1517. depends on VFP
  1518. default y if CPU_V7
  1519. config NEON
  1520. bool "Advanced SIMD (NEON) Extension support"
  1521. depends on VFPv3 && CPU_V7
  1522. help
  1523. Say Y to include support code for NEON, the ARMv7 Advanced SIMD
  1524. Extension.
  1525. config KERNEL_MODE_NEON
  1526. bool "Support for NEON in kernel mode"
  1527. depends on NEON && AEABI
  1528. help
  1529. Say Y to include support for NEON in kernel mode.
  1530. endmenu
  1531. menu "Power management options"
  1532. source "kernel/power/Kconfig"
  1533. config ARCH_SUSPEND_POSSIBLE
  1534. depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
  1535. CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
  1536. def_bool y
  1537. config ARM_CPU_SUSPEND
  1538. def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
  1539. depends on ARCH_SUSPEND_POSSIBLE
  1540. config ARCH_HIBERNATION_POSSIBLE
  1541. bool
  1542. depends on MMU
  1543. default y if ARCH_SUSPEND_POSSIBLE
  1544. endmenu
  1545. source "arch/arm/Kconfig.assembler"