Kconfig 23 KB

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  1. comment "Processor Type"
  2. # Select CPU types depending on the architecture selected. This selects
  3. # which CPUs we support in the kernel image, and the compiler instruction
  4. # optimiser behaviour.
  5. # ARM7TDMI
  6. config CPU_ARM7TDMI
  7. bool "Support ARM7TDMI processor"
  8. depends on !MMU
  9. select CPU_32v4T
  10. select CPU_ABRT_LV4T
  11. select CPU_CACHE_V4
  12. select CPU_PABRT_LEGACY
  13. help
  14. A 32-bit RISC microprocessor based on the ARM7 processor core
  15. which has no memory control unit and cache.
  16. Say Y if you want support for the ARM7TDMI processor.
  17. Otherwise, say N.
  18. # ARM720T
  19. config CPU_ARM720T
  20. bool "Support ARM720T processor" if ARCH_INTEGRATOR
  21. select CPU_32v4T
  22. select CPU_ABRT_LV4T
  23. select CPU_CACHE_V4
  24. select CPU_CACHE_VIVT
  25. select CPU_COPY_V4WT if MMU
  26. select CPU_CP15_MMU
  27. select CPU_PABRT_LEGACY
  28. select CPU_TLB_V4WT if MMU
  29. help
  30. A 32-bit RISC processor with 8kByte Cache, Write Buffer and
  31. MMU built around an ARM7TDMI core.
  32. Say Y if you want support for the ARM720T processor.
  33. Otherwise, say N.
  34. # ARM740T
  35. config CPU_ARM740T
  36. bool "Support ARM740T processor" if ARCH_INTEGRATOR
  37. depends on !MMU
  38. select CPU_32v4T
  39. select CPU_ABRT_LV4T
  40. select CPU_CACHE_V4
  41. select CPU_CP15_MPU
  42. select CPU_PABRT_LEGACY
  43. help
  44. A 32-bit RISC processor with 8KB cache or 4KB variants,
  45. write buffer and MPU(Protection Unit) built around
  46. an ARM7TDMI core.
  47. Say Y if you want support for the ARM740T processor.
  48. Otherwise, say N.
  49. # ARM9TDMI
  50. config CPU_ARM9TDMI
  51. bool "Support ARM9TDMI processor"
  52. depends on !MMU
  53. select CPU_32v4T
  54. select CPU_ABRT_NOMMU
  55. select CPU_CACHE_V4
  56. select CPU_PABRT_LEGACY
  57. help
  58. A 32-bit RISC microprocessor based on the ARM9 processor core
  59. which has no memory control unit and cache.
  60. Say Y if you want support for the ARM9TDMI processor.
  61. Otherwise, say N.
  62. # ARM920T
  63. config CPU_ARM920T
  64. bool "Support ARM920T processor" if ARCH_INTEGRATOR
  65. select CPU_32v4T
  66. select CPU_ABRT_EV4T
  67. select CPU_CACHE_V4WT
  68. select CPU_CACHE_VIVT
  69. select CPU_COPY_V4WB if MMU
  70. select CPU_CP15_MMU
  71. select CPU_PABRT_LEGACY
  72. select CPU_TLB_V4WBI if MMU
  73. help
  74. The ARM920T is licensed to be produced by numerous vendors,
  75. and is used in the Cirrus EP93xx and the Samsung S3C2410.
  76. Say Y if you want support for the ARM920T processor.
  77. Otherwise, say N.
  78. # ARM922T
  79. config CPU_ARM922T
  80. bool "Support ARM922T processor" if ARCH_INTEGRATOR
  81. select CPU_32v4T
  82. select CPU_ABRT_EV4T
  83. select CPU_CACHE_V4WT
  84. select CPU_CACHE_VIVT
  85. select CPU_COPY_V4WB if MMU
  86. select CPU_CP15_MMU
  87. select CPU_PABRT_LEGACY
  88. select CPU_TLB_V4WBI if MMU
  89. help
  90. The ARM922T is a version of the ARM920T, but with smaller
  91. instruction and data caches. It is used in Altera's
  92. Excalibur XA device family and Micrel's KS8695 Centaur.
  93. Say Y if you want support for the ARM922T processor.
  94. Otherwise, say N.
  95. # ARM925T
  96. config CPU_ARM925T
  97. bool "Support ARM925T processor" if ARCH_OMAP1
  98. select CPU_32v4T
  99. select CPU_ABRT_EV4T
  100. select CPU_CACHE_V4WT
  101. select CPU_CACHE_VIVT
  102. select CPU_COPY_V4WB if MMU
  103. select CPU_CP15_MMU
  104. select CPU_PABRT_LEGACY
  105. select CPU_TLB_V4WBI if MMU
  106. help
  107. The ARM925T is a mix between the ARM920T and ARM926T, but with
  108. different instruction and data caches. It is used in TI's OMAP
  109. device family.
  110. Say Y if you want support for the ARM925T processor.
  111. Otherwise, say N.
  112. # ARM926T
  113. config CPU_ARM926T
  114. bool "Support ARM926T processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB
  115. select CPU_32v5
  116. select CPU_ABRT_EV5TJ
  117. select CPU_CACHE_VIVT
  118. select CPU_COPY_V4WB if MMU
  119. select CPU_CP15_MMU
  120. select CPU_PABRT_LEGACY
  121. select CPU_TLB_V4WBI if MMU
  122. help
  123. This is a variant of the ARM920. It has slightly different
  124. instruction sequences for cache and TLB operations. Curiously,
  125. there is no documentation on it at the ARM corporate website.
  126. Say Y if you want support for the ARM926T processor.
  127. Otherwise, say N.
  128. # FA526
  129. config CPU_FA526
  130. bool
  131. select CPU_32v4
  132. select CPU_ABRT_EV4
  133. select CPU_CACHE_FA
  134. select CPU_CACHE_VIVT
  135. select CPU_COPY_FA if MMU
  136. select CPU_CP15_MMU
  137. select CPU_PABRT_LEGACY
  138. select CPU_TLB_FA if MMU
  139. help
  140. The FA526 is a version of the ARMv4 compatible processor with
  141. Branch Target Buffer, Unified TLB and cache line size 16.
  142. Say Y if you want support for the FA526 processor.
  143. Otherwise, say N.
  144. # ARM940T
  145. config CPU_ARM940T
  146. bool "Support ARM940T processor" if ARCH_INTEGRATOR
  147. depends on !MMU
  148. select CPU_32v4T
  149. select CPU_ABRT_NOMMU
  150. select CPU_CACHE_VIVT
  151. select CPU_CP15_MPU
  152. select CPU_PABRT_LEGACY
  153. help
  154. ARM940T is a member of the ARM9TDMI family of general-
  155. purpose microprocessors with MPU and separate 4KB
  156. instruction and 4KB data cases, each with a 4-word line
  157. length.
  158. Say Y if you want support for the ARM940T processor.
  159. Otherwise, say N.
  160. # ARM946E-S
  161. config CPU_ARM946E
  162. bool "Support ARM946E-S processor" if ARCH_INTEGRATOR
  163. depends on !MMU
  164. select CPU_32v5
  165. select CPU_ABRT_NOMMU
  166. select CPU_CACHE_VIVT
  167. select CPU_CP15_MPU
  168. select CPU_PABRT_LEGACY
  169. help
  170. ARM946E-S is a member of the ARM9E-S family of high-
  171. performance, 32-bit system-on-chip processor solutions.
  172. The TCM and ARMv5TE 32-bit instruction set is supported.
  173. Say Y if you want support for the ARM946E-S processor.
  174. Otherwise, say N.
  175. # ARM1020 - needs validating
  176. config CPU_ARM1020
  177. bool "Support ARM1020T (rev 0) processor" if ARCH_INTEGRATOR
  178. select CPU_32v5
  179. select CPU_ABRT_EV4T
  180. select CPU_CACHE_V4WT
  181. select CPU_CACHE_VIVT
  182. select CPU_COPY_V4WB if MMU
  183. select CPU_CP15_MMU
  184. select CPU_PABRT_LEGACY
  185. select CPU_TLB_V4WBI if MMU
  186. help
  187. The ARM1020 is the 32K cached version of the ARM10 processor,
  188. with an addition of a floating-point unit.
  189. Say Y if you want support for the ARM1020 processor.
  190. Otherwise, say N.
  191. # ARM1020E - needs validating
  192. config CPU_ARM1020E
  193. bool "Support ARM1020E processor" if ARCH_INTEGRATOR
  194. depends on n
  195. select CPU_32v5
  196. select CPU_ABRT_EV4T
  197. select CPU_CACHE_V4WT
  198. select CPU_CACHE_VIVT
  199. select CPU_COPY_V4WB if MMU
  200. select CPU_CP15_MMU
  201. select CPU_PABRT_LEGACY
  202. select CPU_TLB_V4WBI if MMU
  203. # ARM1022E
  204. config CPU_ARM1022
  205. bool "Support ARM1022E processor" if ARCH_INTEGRATOR
  206. select CPU_32v5
  207. select CPU_ABRT_EV4T
  208. select CPU_CACHE_VIVT
  209. select CPU_COPY_V4WB if MMU # can probably do better
  210. select CPU_CP15_MMU
  211. select CPU_PABRT_LEGACY
  212. select CPU_TLB_V4WBI if MMU
  213. help
  214. The ARM1022E is an implementation of the ARMv5TE architecture
  215. based upon the ARM10 integer core with a 16KiB L1 Harvard cache,
  216. embedded trace macrocell, and a floating-point unit.
  217. Say Y if you want support for the ARM1022E processor.
  218. Otherwise, say N.
  219. # ARM1026EJ-S
  220. config CPU_ARM1026
  221. bool "Support ARM1026EJ-S processor" if ARCH_INTEGRATOR
  222. select CPU_32v5
  223. select CPU_ABRT_EV5T # But need Jazelle, but EV5TJ ignores bit 10
  224. select CPU_CACHE_VIVT
  225. select CPU_COPY_V4WB if MMU # can probably do better
  226. select CPU_CP15_MMU
  227. select CPU_PABRT_LEGACY
  228. select CPU_TLB_V4WBI if MMU
  229. help
  230. The ARM1026EJ-S is an implementation of the ARMv5TEJ architecture
  231. based upon the ARM10 integer core.
  232. Say Y if you want support for the ARM1026EJ-S processor.
  233. Otherwise, say N.
  234. # SA110
  235. config CPU_SA110
  236. bool "Support StrongARM(R) SA-110 processor" if ARCH_RPC
  237. select CPU_32v3 if ARCH_RPC
  238. select CPU_32v4 if !ARCH_RPC
  239. select CPU_ABRT_EV4
  240. select CPU_CACHE_V4WB
  241. select CPU_CACHE_VIVT
  242. select CPU_COPY_V4WB if MMU
  243. select CPU_CP15_MMU
  244. select CPU_PABRT_LEGACY
  245. select CPU_TLB_V4WB if MMU
  246. help
  247. The Intel StrongARM(R) SA-110 is a 32-bit microprocessor and
  248. is available at five speeds ranging from 100 MHz to 233 MHz.
  249. More information is available at
  250. <http://developer.intel.com/design/strong/sa110.htm>.
  251. Say Y if you want support for the SA-110 processor.
  252. Otherwise, say N.
  253. # SA1100
  254. config CPU_SA1100
  255. bool
  256. select CPU_32v4
  257. select CPU_ABRT_EV4
  258. select CPU_CACHE_V4WB
  259. select CPU_CACHE_VIVT
  260. select CPU_CP15_MMU
  261. select CPU_PABRT_LEGACY
  262. select CPU_TLB_V4WB if MMU
  263. # XScale
  264. config CPU_XSCALE
  265. bool
  266. select CPU_32v5
  267. select CPU_ABRT_EV5T
  268. select CPU_CACHE_VIVT
  269. select CPU_CP15_MMU
  270. select CPU_PABRT_LEGACY
  271. select CPU_TLB_V4WBI if MMU
  272. # XScale Core Version 3
  273. config CPU_XSC3
  274. bool
  275. select CPU_32v5
  276. select CPU_ABRT_EV5T
  277. select CPU_CACHE_VIVT
  278. select CPU_CP15_MMU
  279. select CPU_PABRT_LEGACY
  280. select CPU_TLB_V4WBI if MMU
  281. select IO_36
  282. # Marvell PJ1 (Mohawk)
  283. config CPU_MOHAWK
  284. bool
  285. select CPU_32v5
  286. select CPU_ABRT_EV5T
  287. select CPU_CACHE_VIVT
  288. select CPU_COPY_V4WB if MMU
  289. select CPU_CP15_MMU
  290. select CPU_PABRT_LEGACY
  291. select CPU_TLB_V4WBI if MMU
  292. # Feroceon
  293. config CPU_FEROCEON
  294. bool
  295. select CPU_32v5
  296. select CPU_ABRT_EV5T
  297. select CPU_CACHE_VIVT
  298. select CPU_COPY_FEROCEON if MMU
  299. select CPU_CP15_MMU
  300. select CPU_PABRT_LEGACY
  301. select CPU_TLB_FEROCEON if MMU
  302. config CPU_FEROCEON_OLD_ID
  303. bool "Accept early Feroceon cores with an ARM926 ID"
  304. depends on CPU_FEROCEON && !CPU_ARM926T
  305. default y
  306. help
  307. This enables the usage of some old Feroceon cores
  308. for which the CPU ID is equal to the ARM926 ID.
  309. Relevant for Feroceon-1850 and early Feroceon-2850.
  310. # Marvell PJ4
  311. config CPU_PJ4
  312. bool
  313. select ARM_THUMBEE
  314. select CPU_V7
  315. config CPU_PJ4B
  316. bool
  317. select CPU_V7
  318. # ARMv6
  319. config CPU_V6
  320. bool "Support ARM V6 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX
  321. select CPU_32v6
  322. select CPU_ABRT_EV6
  323. select CPU_CACHE_V6
  324. select CPU_CACHE_VIPT
  325. select CPU_COPY_V6 if MMU
  326. select CPU_CP15_MMU
  327. select CPU_HAS_ASID if MMU
  328. select CPU_PABRT_V6
  329. select CPU_TLB_V6 if MMU
  330. # ARMv6k
  331. config CPU_V6K
  332. bool "Support ARM V6K processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX
  333. select CPU_32v6
  334. select CPU_32v6K
  335. select CPU_ABRT_EV6
  336. select CPU_CACHE_V6
  337. select CPU_CACHE_VIPT
  338. select CPU_COPY_V6 if MMU
  339. select CPU_CP15_MMU
  340. select CPU_HAS_ASID if MMU
  341. select CPU_PABRT_V6
  342. select CPU_TLB_V6 if MMU
  343. # ARMv7
  344. config CPU_V7
  345. bool "Support ARM V7 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX
  346. select CPU_32v6K
  347. select CPU_32v7
  348. select CPU_ABRT_EV7
  349. select CPU_CACHE_V7
  350. select CPU_CACHE_VIPT
  351. select CPU_COPY_V6 if MMU
  352. select CPU_CP15_MMU
  353. select CPU_HAS_ASID if MMU
  354. select CPU_PABRT_V7
  355. select CPU_TLB_V7 if MMU
  356. config CPU_THUMBONLY
  357. bool
  358. # There are no CPUs available with MMU that don't implement an ARM ISA:
  359. depends on !MMU
  360. help
  361. Select this if your CPU doesn't support the 32 bit ARM instructions.
  362. # Figure out what processor architecture version we should be using.
  363. # This defines the compiler instruction set which depends on the machine type.
  364. config CPU_32v3
  365. bool
  366. select CPU_USE_DOMAINS if MMU
  367. select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
  368. select TLS_REG_EMUL if SMP || !MMU
  369. config CPU_32v4
  370. bool
  371. select CPU_USE_DOMAINS if MMU
  372. select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
  373. select TLS_REG_EMUL if SMP || !MMU
  374. config CPU_32v4T
  375. bool
  376. select CPU_USE_DOMAINS if MMU
  377. select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
  378. select TLS_REG_EMUL if SMP || !MMU
  379. config CPU_32v5
  380. bool
  381. select CPU_USE_DOMAINS if MMU
  382. select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
  383. select TLS_REG_EMUL if SMP || !MMU
  384. config CPU_32v6
  385. bool
  386. select CPU_USE_DOMAINS if CPU_V6 && MMU
  387. select TLS_REG_EMUL if !CPU_32v6K && !MMU
  388. config CPU_32v6K
  389. bool
  390. config CPU_32v7
  391. bool
  392. # The abort model
  393. config CPU_ABRT_NOMMU
  394. bool
  395. config CPU_ABRT_EV4
  396. bool
  397. config CPU_ABRT_EV4T
  398. bool
  399. config CPU_ABRT_LV4T
  400. bool
  401. config CPU_ABRT_EV5T
  402. bool
  403. config CPU_ABRT_EV5TJ
  404. bool
  405. config CPU_ABRT_EV6
  406. bool
  407. config CPU_ABRT_EV7
  408. bool
  409. config CPU_PABRT_LEGACY
  410. bool
  411. config CPU_PABRT_V6
  412. bool
  413. config CPU_PABRT_V7
  414. bool
  415. # The cache model
  416. config CPU_CACHE_V4
  417. bool
  418. config CPU_CACHE_V4WT
  419. bool
  420. config CPU_CACHE_V4WB
  421. bool
  422. config CPU_CACHE_V6
  423. bool
  424. config CPU_CACHE_V7
  425. bool
  426. config CPU_CACHE_VIVT
  427. bool
  428. config CPU_CACHE_VIPT
  429. bool
  430. config CPU_CACHE_FA
  431. bool
  432. if MMU
  433. # The copy-page model
  434. config CPU_COPY_V4WT
  435. bool
  436. config CPU_COPY_V4WB
  437. bool
  438. config CPU_COPY_FEROCEON
  439. bool
  440. config CPU_COPY_FA
  441. bool
  442. config CPU_COPY_V6
  443. bool
  444. # This selects the TLB model
  445. config CPU_TLB_V4WT
  446. bool
  447. help
  448. ARM Architecture Version 4 TLB with writethrough cache.
  449. config CPU_TLB_V4WB
  450. bool
  451. help
  452. ARM Architecture Version 4 TLB with writeback cache.
  453. config CPU_TLB_V4WBI
  454. bool
  455. help
  456. ARM Architecture Version 4 TLB with writeback cache and invalidate
  457. instruction cache entry.
  458. config CPU_TLB_FEROCEON
  459. bool
  460. help
  461. Feroceon TLB (v4wbi with non-outer-cachable page table walks).
  462. config CPU_TLB_FA
  463. bool
  464. help
  465. Faraday ARM FA526 architecture, unified TLB with writeback cache
  466. and invalidate instruction cache entry. Branch target buffer is
  467. also supported.
  468. config CPU_TLB_V6
  469. bool
  470. config CPU_TLB_V7
  471. bool
  472. config VERIFY_PERMISSION_FAULT
  473. bool
  474. endif
  475. config CPU_HAS_ASID
  476. bool
  477. help
  478. This indicates whether the CPU has the ASID register; used to
  479. tag TLB and possibly cache entries.
  480. config CPU_CP15
  481. bool
  482. help
  483. Processor has the CP15 register.
  484. config CPU_CP15_MMU
  485. bool
  486. select CPU_CP15
  487. help
  488. Processor has the CP15 register, which has MMU related registers.
  489. config CPU_CP15_MPU
  490. bool
  491. select CPU_CP15
  492. help
  493. Processor has the CP15 register, which has MPU related registers.
  494. config CPU_USE_DOMAINS
  495. bool
  496. help
  497. This option enables or disables the use of domain switching
  498. via the set_fs() function.
  499. #
  500. # CPU supports 36-bit I/O
  501. #
  502. config IO_36
  503. bool
  504. comment "Processor Features"
  505. config ARM_LPAE
  506. bool "Support for the Large Physical Address Extension"
  507. depends on MMU && CPU_32v7 && !CPU_32v6 && !CPU_32v5 && \
  508. !CPU_32v4 && !CPU_32v3
  509. help
  510. Say Y if you have an ARMv7 processor supporting the LPAE page
  511. table format and you would like to access memory beyond the
  512. 4GB limit. The resulting kernel image will not run on
  513. processors without the LPA extension.
  514. If unsure, say N.
  515. config ARCH_PHYS_ADDR_T_64BIT
  516. def_bool ARM_LPAE
  517. config ARCH_DMA_ADDR_T_64BIT
  518. bool
  519. config ARM_THUMB
  520. bool "Support Thumb user binaries" if !CPU_THUMBONLY
  521. depends on CPU_ARM720T || CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_V6 || CPU_V6K || CPU_V7 || CPU_FEROCEON
  522. default y
  523. help
  524. Say Y if you want to include kernel support for running user space
  525. Thumb binaries.
  526. The Thumb instruction set is a compressed form of the standard ARM
  527. instruction set resulting in smaller binaries at the expense of
  528. slightly less efficient code.
  529. If you don't know what this all is, saying Y is a safe choice.
  530. config ARM_THUMBEE
  531. bool "Enable ThumbEE CPU extension"
  532. depends on CPU_V7
  533. help
  534. Say Y here if you have a CPU with the ThumbEE extension and code to
  535. make use of it. Say N for code that can run on CPUs without ThumbEE.
  536. config ARM_VIRT_EXT
  537. bool
  538. depends on MMU
  539. default y if CPU_V7
  540. help
  541. Enable the kernel to make use of the ARM Virtualization
  542. Extensions to install hypervisors without run-time firmware
  543. assistance.
  544. A compliant bootloader is required in order to make maximum
  545. use of this feature. Refer to Documentation/arm/Booting for
  546. details.
  547. config SWP_EMULATE
  548. bool "Emulate SWP/SWPB instructions"
  549. depends on !CPU_USE_DOMAINS && CPU_V7
  550. default y if SMP
  551. select HAVE_PROC_CPU if PROC_FS
  552. help
  553. ARMv6 architecture deprecates use of the SWP/SWPB instructions.
  554. ARMv7 multiprocessing extensions introduce the ability to disable
  555. these instructions, triggering an undefined instruction exception
  556. when executed. Say Y here to enable software emulation of these
  557. instructions for userspace (not kernel) using LDREX/STREX.
  558. Also creates /proc/cpu/swp_emulation for statistics.
  559. In some older versions of glibc [<=2.8] SWP is used during futex
  560. trylock() operations with the assumption that the code will not
  561. be preempted. This invalid assumption may be more likely to fail
  562. with SWP emulation enabled, leading to deadlock of the user
  563. application.
  564. NOTE: when accessing uncached shared regions, LDREX/STREX rely
  565. on an external transaction monitoring block called a global
  566. monitor to maintain update atomicity. If your system does not
  567. implement a global monitor, this option can cause programs that
  568. perform SWP operations to uncached memory to deadlock.
  569. If unsure, say Y.
  570. config CPU_BIG_ENDIAN
  571. bool "Build big-endian kernel"
  572. depends on ARCH_SUPPORTS_BIG_ENDIAN
  573. help
  574. Say Y if you plan on running a kernel in big-endian mode.
  575. Note that your board must be properly built and your board
  576. port must properly enable any big-endian related features
  577. of your chipset/board/processor.
  578. config CPU_ENDIAN_BE8
  579. bool
  580. depends on CPU_BIG_ENDIAN
  581. default CPU_V6 || CPU_V6K || CPU_V7
  582. help
  583. Support for the BE-8 (big-endian) mode on ARMv6 and ARMv7 processors.
  584. config CPU_ENDIAN_BE32
  585. bool
  586. depends on CPU_BIG_ENDIAN
  587. default !CPU_ENDIAN_BE8
  588. help
  589. Support for the BE-32 (big-endian) mode on pre-ARMv6 processors.
  590. config CPU_HIGH_VECTOR
  591. depends on !MMU && CPU_CP15 && !CPU_ARM740T
  592. bool "Select the High exception vector"
  593. help
  594. Say Y here to select high exception vector(0xFFFF0000~).
  595. The exception vector can vary depending on the platform
  596. design in nommu mode. If your platform needs to select
  597. high exception vector, say Y.
  598. Otherwise or if you are unsure, say N, and the low exception
  599. vector (0x00000000~) will be used.
  600. config CPU_ICACHE_DISABLE
  601. bool "Disable I-Cache (I-bit)"
  602. depends on CPU_CP15 && !(CPU_ARM720T || CPU_ARM740T || CPU_XSCALE || CPU_XSC3)
  603. help
  604. Say Y here to disable the processor instruction cache. Unless
  605. you have a reason not to or are unsure, say N.
  606. config CPU_DCACHE_DISABLE
  607. bool "Disable D-Cache (C-bit)"
  608. depends on CPU_CP15
  609. help
  610. Say Y here to disable the processor data cache. Unless
  611. you have a reason not to or are unsure, say N.
  612. config CPU_DCACHE_SIZE
  613. hex
  614. depends on CPU_ARM740T || CPU_ARM946E
  615. default 0x00001000 if CPU_ARM740T
  616. default 0x00002000 # default size for ARM946E-S
  617. help
  618. Some cores are synthesizable to have various sized cache. For
  619. ARM946E-S case, it can vary from 0KB to 1MB.
  620. To support such cache operations, it is efficient to know the size
  621. before compile time.
  622. If your SoC is configured to have a different size, define the value
  623. here with proper conditions.
  624. config CPU_DCACHE_WRITETHROUGH
  625. bool "Force write through D-cache"
  626. depends on (CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_FA526) && !CPU_DCACHE_DISABLE
  627. default y if CPU_ARM925T
  628. help
  629. Say Y here to use the data cache in writethrough mode. Unless you
  630. specifically require this or are unsure, say N.
  631. config CPU_CACHE_ROUND_ROBIN
  632. bool "Round robin I and D cache replacement algorithm"
  633. depends on (CPU_ARM926T || CPU_ARM946E || CPU_ARM1020) && (!CPU_ICACHE_DISABLE || !CPU_DCACHE_DISABLE)
  634. help
  635. Say Y here to use the predictable round-robin cache replacement
  636. policy. Unless you specifically require this or are unsure, say N.
  637. config CPU_BPREDICT_DISABLE
  638. bool "Disable branch prediction"
  639. depends on CPU_ARM1020 || CPU_V6 || CPU_V6K || CPU_MOHAWK || CPU_XSC3 || CPU_V7 || CPU_FA526
  640. help
  641. Say Y here to disable branch prediction. If unsure, say N.
  642. config TLS_REG_EMUL
  643. bool
  644. help
  645. An SMP system using a pre-ARMv6 processor (there are apparently
  646. a few prototypes like that in existence) and therefore access to
  647. that required register must be emulated.
  648. config NEEDS_SYSCALL_FOR_CMPXCHG
  649. bool
  650. help
  651. SMP on a pre-ARMv6 processor? Well OK then.
  652. Forget about fast user space cmpxchg support.
  653. It is just not possible.
  654. config DMA_CACHE_RWFO
  655. bool "Enable read/write for ownership DMA cache maintenance"
  656. depends on CPU_V6K && SMP
  657. default y
  658. help
  659. The Snoop Control Unit on ARM11MPCore does not detect the
  660. cache maintenance operations and the dma_{map,unmap}_area()
  661. functions may leave stale cache entries on other CPUs. By
  662. enabling this option, Read or Write For Ownership in the ARMv6
  663. DMA cache maintenance functions is performed. These LDR/STR
  664. instructions change the cache line state to shared or modified
  665. so that the cache operation has the desired effect.
  666. Note that the workaround is only valid on processors that do
  667. not perform speculative loads into the D-cache. For such
  668. processors, if cache maintenance operations are not broadcast
  669. in hardware, other workarounds are needed (e.g. cache
  670. maintenance broadcasting in software via FIQ).
  671. config OUTER_CACHE
  672. bool
  673. config OUTER_CACHE_SYNC
  674. bool
  675. help
  676. The outer cache has a outer_cache_fns.sync function pointer
  677. that can be used to drain the write buffer of the outer cache.
  678. config CACHE_FEROCEON_L2
  679. bool "Enable the Feroceon L2 cache controller"
  680. depends on ARCH_KIRKWOOD || ARCH_MV78XX0
  681. default y
  682. select OUTER_CACHE
  683. help
  684. This option enables the Feroceon L2 cache controller.
  685. config CACHE_FEROCEON_L2_WRITETHROUGH
  686. bool "Force Feroceon L2 cache write through"
  687. depends on CACHE_FEROCEON_L2
  688. help
  689. Say Y here to use the Feroceon L2 cache in writethrough mode.
  690. Unless you specifically require this, say N for writeback mode.
  691. config MIGHT_HAVE_CACHE_L2X0
  692. bool
  693. help
  694. This option should be selected by machines which have a L2x0
  695. or PL310 cache controller, but where its use is optional.
  696. The only effect of this option is to make CACHE_L2X0 and
  697. related options available to the user for configuration.
  698. Boards or SoCs which always require the cache controller
  699. support to be present should select CACHE_L2X0 directly
  700. instead of this option, thus preventing the user from
  701. inadvertently configuring a broken kernel.
  702. config CACHE_L2X0
  703. bool "Enable the L2x0 outer cache controller" if MIGHT_HAVE_CACHE_L2X0
  704. default MIGHT_HAVE_CACHE_L2X0
  705. select OUTER_CACHE
  706. select OUTER_CACHE_SYNC
  707. help
  708. This option enables the L2x0 PrimeCell.
  709. config CACHE_PL310
  710. bool
  711. depends on CACHE_L2X0
  712. default y if CPU_V7 && !(CPU_V6 || CPU_V6K)
  713. help
  714. This option enables optimisations for the PL310 cache
  715. controller.
  716. config CACHE_TAUROS2
  717. bool "Enable the Tauros2 L2 cache controller"
  718. depends on (ARCH_DOVE || ARCH_MMP || CPU_PJ4)
  719. default y
  720. select OUTER_CACHE
  721. help
  722. This option enables the Tauros2 L2 cache controller (as
  723. found on PJ1/PJ4).
  724. config CACHE_XSC3L2
  725. bool "Enable the L2 cache on XScale3"
  726. depends on CPU_XSC3
  727. default y
  728. select OUTER_CACHE
  729. help
  730. This option enables the L2 cache on XScale3.
  731. config ARM_L1_CACHE_SHIFT_6
  732. bool
  733. default y if CPU_V7
  734. help
  735. Setting ARM L1 cache line size to 64 Bytes.
  736. config ARM_L1_CACHE_SHIFT
  737. int
  738. default 6 if ARM_L1_CACHE_SHIFT_6
  739. default 5
  740. config ARM_DMA_MEM_BUFFERABLE
  741. bool "Use non-cacheable memory for DMA" if (CPU_V6 || CPU_V6K) && !CPU_V7
  742. depends on !(MACH_REALVIEW_PB1176 || REALVIEW_EB_ARM11MP || \
  743. MACH_REALVIEW_PB11MP)
  744. default y if CPU_V6 || CPU_V6K || CPU_V7
  745. help
  746. Historically, the kernel has used strongly ordered mappings to
  747. provide DMA coherent memory. With the advent of ARMv7, mapping
  748. memory with differing types results in unpredictable behaviour,
  749. so on these CPUs, this option is forced on.
  750. Multiple mappings with differing attributes is also unpredictable
  751. on ARMv6 CPUs, but since they do not have aggressive speculative
  752. prefetch, no harm appears to occur.
  753. However, drivers may be missing the necessary barriers for ARMv6,
  754. and therefore turning this on may result in unpredictable driver
  755. behaviour. Therefore, we offer this as an option.
  756. You are recommended say 'Y' here and debug any affected drivers.
  757. config ARCH_HAS_BARRIERS
  758. bool
  759. help
  760. This option allows the use of custom mandatory barriers
  761. included via the mach/barriers.h file.