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. # ARM610
  6. config CPU_ARM610
  7. bool "Support ARM610 processor" if ARCH_RPC
  8. select CPU_32v3
  9. select CPU_CACHE_V3
  10. select CPU_CACHE_VIVT
  11. select CPU_CP15_MMU
  12. select CPU_COPY_V3 if MMU
  13. select CPU_TLB_V3 if MMU
  14. select CPU_PABRT_LEGACY
  15. help
  16. The ARM610 is the successor to the ARM3 processor
  17. and was produced by VLSI Technology Inc.
  18. Say Y if you want support for the ARM610 processor.
  19. Otherwise, say N.
  20. # ARM7TDMI
  21. config CPU_ARM7TDMI
  22. bool "Support ARM7TDMI processor"
  23. depends on !MMU
  24. select CPU_32v4T
  25. select CPU_ABRT_LV4T
  26. select CPU_PABRT_LEGACY
  27. select CPU_CACHE_V4
  28. help
  29. A 32-bit RISC microprocessor based on the ARM7 processor core
  30. which has no memory control unit and cache.
  31. Say Y if you want support for the ARM7TDMI processor.
  32. Otherwise, say N.
  33. # ARM710
  34. config CPU_ARM710
  35. bool "Support ARM710 processor" if ARCH_RPC
  36. select CPU_32v3
  37. select CPU_CACHE_V3
  38. select CPU_CACHE_VIVT
  39. select CPU_CP15_MMU
  40. select CPU_COPY_V3 if MMU
  41. select CPU_TLB_V3 if MMU
  42. select CPU_PABRT_LEGACY
  43. help
  44. A 32-bit RISC microprocessor based on the ARM7 processor core
  45. designed by Advanced RISC Machines Ltd. The ARM710 is the
  46. successor to the ARM610 processor. It was released in
  47. July 1994 by VLSI Technology Inc.
  48. Say Y if you want support for the ARM710 processor.
  49. Otherwise, say N.
  50. # ARM720T
  51. config CPU_ARM720T
  52. bool "Support ARM720T processor" if ARCH_INTEGRATOR
  53. select CPU_32v4T
  54. select CPU_ABRT_LV4T
  55. select CPU_PABRT_LEGACY
  56. select CPU_CACHE_V4
  57. select CPU_CACHE_VIVT
  58. select CPU_CP15_MMU
  59. select CPU_COPY_V4WT if MMU
  60. select CPU_TLB_V4WT if MMU
  61. help
  62. A 32-bit RISC processor with 8kByte Cache, Write Buffer and
  63. MMU built around an ARM7TDMI core.
  64. Say Y if you want support for the ARM720T processor.
  65. Otherwise, say N.
  66. # ARM740T
  67. config CPU_ARM740T
  68. bool "Support ARM740T processor" if ARCH_INTEGRATOR
  69. depends on !MMU
  70. select CPU_32v4T
  71. select CPU_ABRT_LV4T
  72. select CPU_PABRT_LEGACY
  73. select CPU_CACHE_V3 # although the core is v4t
  74. select CPU_CP15_MPU
  75. help
  76. A 32-bit RISC processor with 8KB cache or 4KB variants,
  77. write buffer and MPU(Protection Unit) built around
  78. an ARM7TDMI core.
  79. Say Y if you want support for the ARM740T processor.
  80. Otherwise, say N.
  81. # ARM9TDMI
  82. config CPU_ARM9TDMI
  83. bool "Support ARM9TDMI processor"
  84. depends on !MMU
  85. select CPU_32v4T
  86. select CPU_ABRT_NOMMU
  87. select CPU_PABRT_LEGACY
  88. select CPU_CACHE_V4
  89. help
  90. A 32-bit RISC microprocessor based on the ARM9 processor core
  91. which has no memory control unit and cache.
  92. Say Y if you want support for the ARM9TDMI processor.
  93. Otherwise, say N.
  94. # ARM920T
  95. config CPU_ARM920T
  96. bool "Support ARM920T processor" if ARCH_INTEGRATOR
  97. select CPU_32v4T
  98. select CPU_ABRT_EV4T
  99. select CPU_PABRT_LEGACY
  100. select CPU_CACHE_V4WT
  101. select CPU_CACHE_VIVT
  102. select CPU_CP15_MMU
  103. select CPU_COPY_V4WB if MMU
  104. select CPU_TLB_V4WBI if MMU
  105. help
  106. The ARM920T is licensed to be produced by numerous vendors,
  107. and is used in the Cirrus EP93xx and the Samsung S3C2410.
  108. Say Y if you want support for the ARM920T processor.
  109. Otherwise, say N.
  110. # ARM922T
  111. config CPU_ARM922T
  112. bool "Support ARM922T processor" if ARCH_INTEGRATOR
  113. select CPU_32v4T
  114. select CPU_ABRT_EV4T
  115. select CPU_PABRT_LEGACY
  116. select CPU_CACHE_V4WT
  117. select CPU_CACHE_VIVT
  118. select CPU_CP15_MMU
  119. select CPU_COPY_V4WB if MMU
  120. select CPU_TLB_V4WBI if MMU
  121. help
  122. The ARM922T is a version of the ARM920T, but with smaller
  123. instruction and data caches. It is used in Altera's
  124. Excalibur XA device family and Micrel's KS8695 Centaur.
  125. Say Y if you want support for the ARM922T processor.
  126. Otherwise, say N.
  127. # ARM925T
  128. config CPU_ARM925T
  129. bool "Support ARM925T processor" if ARCH_OMAP1
  130. select CPU_32v4T
  131. select CPU_ABRT_EV4T
  132. select CPU_PABRT_LEGACY
  133. select CPU_CACHE_V4WT
  134. select CPU_CACHE_VIVT
  135. select CPU_CP15_MMU
  136. select CPU_COPY_V4WB if MMU
  137. select CPU_TLB_V4WBI if MMU
  138. help
  139. The ARM925T is a mix between the ARM920T and ARM926T, but with
  140. different instruction and data caches. It is used in TI's OMAP
  141. device family.
  142. Say Y if you want support for the ARM925T processor.
  143. Otherwise, say N.
  144. # ARM926T
  145. config CPU_ARM926T
  146. bool "Support ARM926T processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB
  147. select CPU_32v5
  148. select CPU_ABRT_EV5TJ
  149. select CPU_PABRT_LEGACY
  150. select CPU_CACHE_VIVT
  151. select CPU_CP15_MMU
  152. select CPU_COPY_V4WB if MMU
  153. select CPU_TLB_V4WBI if MMU
  154. help
  155. This is a variant of the ARM920. It has slightly different
  156. instruction sequences for cache and TLB operations. Curiously,
  157. there is no documentation on it at the ARM corporate website.
  158. Say Y if you want support for the ARM926T processor.
  159. Otherwise, say N.
  160. # FA526
  161. config CPU_FA526
  162. bool
  163. select CPU_32v4
  164. select CPU_ABRT_EV4
  165. select CPU_PABRT_LEGACY
  166. select CPU_CACHE_VIVT
  167. select CPU_CP15_MMU
  168. select CPU_CACHE_FA
  169. select CPU_COPY_FA if MMU
  170. select CPU_TLB_FA if MMU
  171. help
  172. The FA526 is a version of the ARMv4 compatible processor with
  173. Branch Target Buffer, Unified TLB and cache line size 16.
  174. Say Y if you want support for the FA526 processor.
  175. Otherwise, say N.
  176. # ARM940T
  177. config CPU_ARM940T
  178. bool "Support ARM940T processor" if ARCH_INTEGRATOR
  179. depends on !MMU
  180. select CPU_32v4T
  181. select CPU_ABRT_NOMMU
  182. select CPU_PABRT_LEGACY
  183. select CPU_CACHE_VIVT
  184. select CPU_CP15_MPU
  185. help
  186. ARM940T is a member of the ARM9TDMI family of general-
  187. purpose microprocessors with MPU and separate 4KB
  188. instruction and 4KB data cases, each with a 4-word line
  189. length.
  190. Say Y if you want support for the ARM940T processor.
  191. Otherwise, say N.
  192. # ARM946E-S
  193. config CPU_ARM946E
  194. bool "Support ARM946E-S processor" if ARCH_INTEGRATOR
  195. depends on !MMU
  196. select CPU_32v5
  197. select CPU_ABRT_NOMMU
  198. select CPU_PABRT_LEGACY
  199. select CPU_CACHE_VIVT
  200. select CPU_CP15_MPU
  201. help
  202. ARM946E-S is a member of the ARM9E-S family of high-
  203. performance, 32-bit system-on-chip processor solutions.
  204. The TCM and ARMv5TE 32-bit instruction set is supported.
  205. Say Y if you want support for the ARM946E-S processor.
  206. Otherwise, say N.
  207. # ARM1020 - needs validating
  208. config CPU_ARM1020
  209. bool "Support ARM1020T (rev 0) processor" if ARCH_INTEGRATOR
  210. select CPU_32v5
  211. select CPU_ABRT_EV4T
  212. select CPU_PABRT_LEGACY
  213. select CPU_CACHE_V4WT
  214. select CPU_CACHE_VIVT
  215. select CPU_CP15_MMU
  216. select CPU_COPY_V4WB if MMU
  217. select CPU_TLB_V4WBI if MMU
  218. help
  219. The ARM1020 is the 32K cached version of the ARM10 processor,
  220. with an addition of a floating-point unit.
  221. Say Y if you want support for the ARM1020 processor.
  222. Otherwise, say N.
  223. # ARM1020E - needs validating
  224. config CPU_ARM1020E
  225. bool "Support ARM1020E processor" if ARCH_INTEGRATOR
  226. select CPU_32v5
  227. select CPU_ABRT_EV4T
  228. select CPU_PABRT_LEGACY
  229. select CPU_CACHE_V4WT
  230. select CPU_CACHE_VIVT
  231. select CPU_CP15_MMU
  232. select CPU_COPY_V4WB if MMU
  233. select CPU_TLB_V4WBI if MMU
  234. depends on n
  235. # ARM1022E
  236. config CPU_ARM1022
  237. bool "Support ARM1022E processor" if ARCH_INTEGRATOR
  238. select CPU_32v5
  239. select CPU_ABRT_EV4T
  240. select CPU_PABRT_LEGACY
  241. select CPU_CACHE_VIVT
  242. select CPU_CP15_MMU
  243. select CPU_COPY_V4WB if MMU # can probably do better
  244. select CPU_TLB_V4WBI if MMU
  245. help
  246. The ARM1022E is an implementation of the ARMv5TE architecture
  247. based upon the ARM10 integer core with a 16KiB L1 Harvard cache,
  248. embedded trace macrocell, and a floating-point unit.
  249. Say Y if you want support for the ARM1022E processor.
  250. Otherwise, say N.
  251. # ARM1026EJ-S
  252. config CPU_ARM1026
  253. bool "Support ARM1026EJ-S processor" if ARCH_INTEGRATOR
  254. select CPU_32v5
  255. select CPU_ABRT_EV5T # But need Jazelle, but EV5TJ ignores bit 10
  256. select CPU_PABRT_LEGACY
  257. select CPU_CACHE_VIVT
  258. select CPU_CP15_MMU
  259. select CPU_COPY_V4WB if MMU # can probably do better
  260. select CPU_TLB_V4WBI if MMU
  261. help
  262. The ARM1026EJ-S is an implementation of the ARMv5TEJ architecture
  263. based upon the ARM10 integer core.
  264. Say Y if you want support for the ARM1026EJ-S processor.
  265. Otherwise, say N.
  266. # SA110
  267. config CPU_SA110
  268. bool "Support StrongARM(R) SA-110 processor" if ARCH_RPC
  269. select CPU_32v3 if ARCH_RPC
  270. select CPU_32v4 if !ARCH_RPC
  271. select CPU_ABRT_EV4
  272. select CPU_PABRT_LEGACY
  273. select CPU_CACHE_V4WB
  274. select CPU_CACHE_VIVT
  275. select CPU_CP15_MMU
  276. select CPU_COPY_V4WB if MMU
  277. select CPU_TLB_V4WB if MMU
  278. help
  279. The Intel StrongARM(R) SA-110 is a 32-bit microprocessor and
  280. is available at five speeds ranging from 100 MHz to 233 MHz.
  281. More information is available at
  282. <http://developer.intel.com/design/strong/sa110.htm>.
  283. Say Y if you want support for the SA-110 processor.
  284. Otherwise, say N.
  285. # SA1100
  286. config CPU_SA1100
  287. bool
  288. select CPU_32v4
  289. select CPU_ABRT_EV4
  290. select CPU_PABRT_LEGACY
  291. select CPU_CACHE_V4WB
  292. select CPU_CACHE_VIVT
  293. select CPU_CP15_MMU
  294. select CPU_TLB_V4WB if MMU
  295. # XScale
  296. config CPU_XSCALE
  297. bool
  298. select CPU_32v5
  299. select CPU_ABRT_EV5T
  300. select CPU_PABRT_LEGACY
  301. select CPU_CACHE_VIVT
  302. select CPU_CP15_MMU
  303. select CPU_TLB_V4WBI if MMU
  304. # XScale Core Version 3
  305. config CPU_XSC3
  306. bool
  307. select CPU_32v5
  308. select CPU_ABRT_EV5T
  309. select CPU_PABRT_LEGACY
  310. select CPU_CACHE_VIVT
  311. select CPU_CP15_MMU
  312. select CPU_TLB_V4WBI if MMU
  313. select IO_36
  314. # Marvell PJ1 (Mohawk)
  315. config CPU_MOHAWK
  316. bool
  317. select CPU_32v5
  318. select CPU_ABRT_EV5T
  319. select CPU_PABRT_LEGACY
  320. select CPU_CACHE_VIVT
  321. select CPU_CP15_MMU
  322. select CPU_TLB_V4WBI if MMU
  323. select CPU_COPY_V4WB if MMU
  324. # Feroceon
  325. config CPU_FEROCEON
  326. bool
  327. select CPU_32v5
  328. select CPU_ABRT_EV5T
  329. select CPU_PABRT_LEGACY
  330. select CPU_CACHE_VIVT
  331. select CPU_CP15_MMU
  332. select CPU_COPY_FEROCEON if MMU
  333. select CPU_TLB_FEROCEON if MMU
  334. config CPU_FEROCEON_OLD_ID
  335. bool "Accept early Feroceon cores with an ARM926 ID"
  336. depends on CPU_FEROCEON && !CPU_ARM926T
  337. default y
  338. help
  339. This enables the usage of some old Feroceon cores
  340. for which the CPU ID is equal to the ARM926 ID.
  341. Relevant for Feroceon-1850 and early Feroceon-2850.
  342. # Marvell PJ4
  343. config CPU_PJ4
  344. bool
  345. select CPU_V7
  346. select ARM_THUMBEE
  347. # ARMv6
  348. config CPU_V6
  349. bool "Support ARM V6 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX || ARCH_DOVE
  350. select CPU_32v6
  351. select CPU_ABRT_EV6
  352. select CPU_PABRT_V6
  353. select CPU_CACHE_V6
  354. select CPU_CACHE_VIPT
  355. select CPU_CP15_MMU
  356. select CPU_HAS_ASID if MMU
  357. select CPU_COPY_V6 if MMU
  358. select CPU_TLB_V6 if MMU
  359. # ARMv6k
  360. config CPU_32v6K
  361. bool "Support ARM V6K processor extensions" if !SMP
  362. depends on CPU_V6 || CPU_V7
  363. default y if SMP && !(ARCH_MX3 || ARCH_OMAP2)
  364. help
  365. Say Y here if your ARMv6 processor supports the 'K' extension.
  366. This enables the kernel to use some instructions not present
  367. on previous processors, and as such a kernel build with this
  368. enabled will not boot on processors with do not support these
  369. instructions.
  370. # ARMv7
  371. config CPU_V7
  372. bool "Support ARM V7 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX
  373. select CPU_32v6K if !ARCH_OMAP2
  374. select CPU_32v7
  375. select CPU_ABRT_EV7
  376. select CPU_PABRT_V7
  377. select CPU_CACHE_V7
  378. select CPU_CACHE_VIPT
  379. select CPU_CP15_MMU
  380. select CPU_HAS_ASID if MMU
  381. select CPU_COPY_V6 if MMU
  382. select CPU_TLB_V7 if MMU
  383. # Figure out what processor architecture version we should be using.
  384. # This defines the compiler instruction set which depends on the machine type.
  385. config CPU_32v3
  386. bool
  387. select TLS_REG_EMUL if SMP || !MMU
  388. select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
  389. config CPU_32v4
  390. bool
  391. select TLS_REG_EMUL if SMP || !MMU
  392. select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
  393. config CPU_32v4T
  394. bool
  395. select TLS_REG_EMUL if SMP || !MMU
  396. select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
  397. config CPU_32v5
  398. bool
  399. select TLS_REG_EMUL if SMP || !MMU
  400. select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
  401. config CPU_32v6
  402. bool
  403. select TLS_REG_EMUL if !CPU_32v6K && !MMU
  404. config CPU_32v7
  405. bool
  406. # The abort model
  407. config CPU_ABRT_NOMMU
  408. bool
  409. config CPU_ABRT_EV4
  410. bool
  411. config CPU_ABRT_EV4T
  412. bool
  413. config CPU_ABRT_LV4T
  414. bool
  415. config CPU_ABRT_EV5T
  416. bool
  417. config CPU_ABRT_EV5TJ
  418. bool
  419. config CPU_ABRT_EV6
  420. bool
  421. config CPU_ABRT_EV7
  422. bool
  423. config CPU_PABRT_LEGACY
  424. bool
  425. config CPU_PABRT_V6
  426. bool
  427. config CPU_PABRT_V7
  428. bool
  429. # The cache model
  430. config CPU_CACHE_V3
  431. bool
  432. config CPU_CACHE_V4
  433. bool
  434. config CPU_CACHE_V4WT
  435. bool
  436. config CPU_CACHE_V4WB
  437. bool
  438. config CPU_CACHE_V6
  439. bool
  440. config CPU_CACHE_V7
  441. bool
  442. config CPU_CACHE_VIVT
  443. bool
  444. config CPU_CACHE_VIPT
  445. bool
  446. config CPU_CACHE_FA
  447. bool
  448. if MMU
  449. # The copy-page model
  450. config CPU_COPY_V3
  451. bool
  452. config CPU_COPY_V4WT
  453. bool
  454. config CPU_COPY_V4WB
  455. bool
  456. config CPU_COPY_FEROCEON
  457. bool
  458. config CPU_COPY_FA
  459. bool
  460. config CPU_COPY_V6
  461. bool
  462. # This selects the TLB model
  463. config CPU_TLB_V3
  464. bool
  465. help
  466. ARM Architecture Version 3 TLB.
  467. config CPU_TLB_V4WT
  468. bool
  469. help
  470. ARM Architecture Version 4 TLB with writethrough cache.
  471. config CPU_TLB_V4WB
  472. bool
  473. help
  474. ARM Architecture Version 4 TLB with writeback cache.
  475. config CPU_TLB_V4WBI
  476. bool
  477. help
  478. ARM Architecture Version 4 TLB with writeback cache and invalidate
  479. instruction cache entry.
  480. config CPU_TLB_FEROCEON
  481. bool
  482. help
  483. Feroceon TLB (v4wbi with non-outer-cachable page table walks).
  484. config CPU_TLB_FA
  485. bool
  486. help
  487. Faraday ARM FA526 architecture, unified TLB with writeback cache
  488. and invalidate instruction cache entry. Branch target buffer is
  489. also supported.
  490. config CPU_TLB_V6
  491. bool
  492. config CPU_TLB_V7
  493. bool
  494. config VERIFY_PERMISSION_FAULT
  495. bool
  496. endif
  497. config CPU_HAS_ASID
  498. bool
  499. help
  500. This indicates whether the CPU has the ASID register; used to
  501. tag TLB and possibly cache entries.
  502. config CPU_CP15
  503. bool
  504. help
  505. Processor has the CP15 register.
  506. config CPU_CP15_MMU
  507. bool
  508. select CPU_CP15
  509. help
  510. Processor has the CP15 register, which has MMU related registers.
  511. config CPU_CP15_MPU
  512. bool
  513. select CPU_CP15
  514. help
  515. Processor has the CP15 register, which has MPU related registers.
  516. config CPU_USE_DOMAINS
  517. bool
  518. depends on MMU
  519. default y if !CPU_32v6K
  520. help
  521. This option enables or disables the use of domain switching
  522. via the set_fs() function.
  523. #
  524. # CPU supports 36-bit I/O
  525. #
  526. config IO_36
  527. bool
  528. comment "Processor Features"
  529. config ARM_THUMB
  530. bool "Support Thumb user binaries"
  531. 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_V7 || CPU_FEROCEON
  532. default y
  533. help
  534. Say Y if you want to include kernel support for running user space
  535. Thumb binaries.
  536. The Thumb instruction set is a compressed form of the standard ARM
  537. instruction set resulting in smaller binaries at the expense of
  538. slightly less efficient code.
  539. If you don't know what this all is, saying Y is a safe choice.
  540. config ARM_THUMBEE
  541. bool "Enable ThumbEE CPU extension"
  542. depends on CPU_V7
  543. help
  544. Say Y here if you have a CPU with the ThumbEE extension and code to
  545. make use of it. Say N for code that can run on CPUs without ThumbEE.
  546. config SWP_EMULATE
  547. bool "Emulate SWP/SWPB instructions"
  548. depends on CPU_V7 && !CPU_V6
  549. select HAVE_PROC_CPU if PROC_FS
  550. default y if SMP
  551. help
  552. ARMv6 architecture deprecates use of the SWP/SWPB instructions.
  553. ARMv7 multiprocessing extensions introduce the ability to disable
  554. these instructions, triggering an undefined instruction exception
  555. when executed. Say Y here to enable software emulation of these
  556. instructions for userspace (not kernel) using LDREX/STREX.
  557. Also creates /proc/cpu/swp_emulation for statistics.
  558. In some older versions of glibc [<=2.8] SWP is used during futex
  559. trylock() operations with the assumption that the code will not
  560. be preempted. This invalid assumption may be more likely to fail
  561. with SWP emulation enabled, leading to deadlock of the user
  562. application.
  563. NOTE: when accessing uncached shared regions, LDREX/STREX rely
  564. on an external transaction monitoring block called a global
  565. monitor to maintain update atomicity. If your system does not
  566. implement a global monitor, this option can cause programs that
  567. perform SWP operations to uncached memory to deadlock.
  568. If unsure, say Y.
  569. config CPU_BIG_ENDIAN
  570. bool "Build big-endian kernel"
  571. depends on ARCH_SUPPORTS_BIG_ENDIAN
  572. help
  573. Say Y if you plan on running a kernel in big-endian mode.
  574. Note that your board must be properly built and your board
  575. port must properly enable any big-endian related features
  576. of your chipset/board/processor.
  577. config CPU_ENDIAN_BE8
  578. bool
  579. depends on CPU_BIG_ENDIAN
  580. default CPU_V6 || CPU_V7
  581. help
  582. Support for the BE-8 (big-endian) mode on ARMv6 and ARMv7 processors.
  583. config CPU_ENDIAN_BE32
  584. bool
  585. depends on CPU_BIG_ENDIAN
  586. default !CPU_ENDIAN_BE8
  587. help
  588. Support for the BE-32 (big-endian) mode on pre-ARMv6 processors.
  589. config CPU_HIGH_VECTOR
  590. depends on !MMU && CPU_CP15 && !CPU_ARM740T
  591. bool "Select the High exception vector"
  592. help
  593. Say Y here to select high exception vector(0xFFFF0000~).
  594. The exception vector can be vary depending on the platform
  595. design in nommu mode. If your platform needs to select
  596. high exception vector, say Y.
  597. Otherwise or if you are unsure, say N, and the low exception
  598. vector (0x00000000~) will be used.
  599. config CPU_ICACHE_DISABLE
  600. bool "Disable I-Cache (I-bit)"
  601. depends on CPU_CP15 && !(CPU_ARM610 || CPU_ARM710 || CPU_ARM720T || CPU_ARM740T || CPU_XSCALE || CPU_XSC3)
  602. help
  603. Say Y here to disable the processor instruction cache. Unless
  604. you have a reason not to or are unsure, say N.
  605. config CPU_DCACHE_DISABLE
  606. bool "Disable D-Cache (C-bit)"
  607. depends on CPU_CP15
  608. help
  609. Say Y here to disable the processor data cache. Unless
  610. you have a reason not to or are unsure, say N.
  611. config CPU_DCACHE_SIZE
  612. hex
  613. depends on CPU_ARM740T || CPU_ARM946E
  614. default 0x00001000 if CPU_ARM740T
  615. default 0x00002000 # default size for ARM946E-S
  616. help
  617. Some cores are synthesizable to have various sized cache. For
  618. ARM946E-S case, it can vary from 0KB to 1MB.
  619. To support such cache operations, it is efficient to know the size
  620. before compile time.
  621. If your SoC is configured to have a different size, define the value
  622. here with proper conditions.
  623. config CPU_DCACHE_WRITETHROUGH
  624. bool "Force write through D-cache"
  625. depends on (CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_FA526) && !CPU_DCACHE_DISABLE
  626. default y if CPU_ARM925T
  627. help
  628. Say Y here to use the data cache in writethrough mode. Unless you
  629. specifically require this or are unsure, say N.
  630. config CPU_CACHE_ROUND_ROBIN
  631. bool "Round robin I and D cache replacement algorithm"
  632. depends on (CPU_ARM926T || CPU_ARM946E || CPU_ARM1020) && (!CPU_ICACHE_DISABLE || !CPU_DCACHE_DISABLE)
  633. help
  634. Say Y here to use the predictable round-robin cache replacement
  635. policy. Unless you specifically require this or are unsure, say N.
  636. config CPU_BPREDICT_DISABLE
  637. bool "Disable branch prediction"
  638. depends on CPU_ARM1020 || CPU_V6 || CPU_MOHAWK || CPU_XSC3 || CPU_V7 || CPU_FA526
  639. help
  640. Say Y here to disable branch prediction. If unsure, say N.
  641. config TLS_REG_EMUL
  642. bool
  643. help
  644. An SMP system using a pre-ARMv6 processor (there are apparently
  645. a few prototypes like that in existence) and therefore access to
  646. that required register must be emulated.
  647. config NEEDS_SYSCALL_FOR_CMPXCHG
  648. bool
  649. help
  650. SMP on a pre-ARMv6 processor? Well OK then.
  651. Forget about fast user space cmpxchg support.
  652. It is just not possible.
  653. config DMA_CACHE_RWFO
  654. bool "Enable read/write for ownership DMA cache maintenance"
  655. depends on CPU_V6 && SMP
  656. default y
  657. help
  658. The Snoop Control Unit on ARM11MPCore does not detect the
  659. cache maintenance operations and the dma_{map,unmap}_area()
  660. functions may leave stale cache entries on other CPUs. By
  661. enabling this option, Read or Write For Ownership in the ARMv6
  662. DMA cache maintenance functions is performed. These LDR/STR
  663. instructions change the cache line state to shared or modified
  664. so that the cache operation has the desired effect.
  665. Note that the workaround is only valid on processors that do
  666. not perform speculative loads into the D-cache. For such
  667. processors, if cache maintenance operations are not broadcast
  668. in hardware, other workarounds are needed (e.g. cache
  669. maintenance broadcasting in software via FIQ).
  670. config OUTER_CACHE
  671. bool
  672. config OUTER_CACHE_SYNC
  673. bool
  674. help
  675. The outer cache has a outer_cache_fns.sync function pointer
  676. that can be used to drain the write buffer of the outer cache.
  677. config CACHE_FEROCEON_L2
  678. bool "Enable the Feroceon L2 cache controller"
  679. depends on ARCH_KIRKWOOD || ARCH_MV78XX0
  680. default y
  681. select OUTER_CACHE
  682. help
  683. This option enables the Feroceon L2 cache controller.
  684. config CACHE_FEROCEON_L2_WRITETHROUGH
  685. bool "Force Feroceon L2 cache write through"
  686. depends on CACHE_FEROCEON_L2
  687. help
  688. Say Y here to use the Feroceon L2 cache in writethrough mode.
  689. Unless you specifically require this, say N for writeback mode.
  690. config CACHE_L2X0
  691. bool "Enable the L2x0 outer cache controller"
  692. depends on REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || MACH_REALVIEW_PB1176 || \
  693. REALVIEW_EB_A9MP || ARCH_MX35 || ARCH_MX31 || MACH_REALVIEW_PBX || \
  694. ARCH_NOMADIK || ARCH_OMAP4 || ARCH_S5PV310 || ARCH_TEGRA || \
  695. ARCH_U8500 || ARCH_VEXPRESS_CA9X4 || ARCH_SHMOBILE
  696. default y
  697. select OUTER_CACHE
  698. select OUTER_CACHE_SYNC
  699. help
  700. This option enables the L2x0 PrimeCell.
  701. config CACHE_PL310
  702. bool
  703. depends on CACHE_L2X0
  704. default y if CPU_V7 && !CPU_V6
  705. help
  706. This option enables optimisations for the PL310 cache
  707. controller.
  708. config CACHE_TAUROS2
  709. bool "Enable the Tauros2 L2 cache controller"
  710. depends on (ARCH_DOVE || ARCH_MMP || CPU_PJ4)
  711. default y
  712. select OUTER_CACHE
  713. help
  714. This option enables the Tauros2 L2 cache controller (as
  715. found on PJ1/PJ4).
  716. config CACHE_XSC3L2
  717. bool "Enable the L2 cache on XScale3"
  718. depends on CPU_XSC3
  719. default y
  720. select OUTER_CACHE
  721. help
  722. This option enables the L2 cache on XScale3.
  723. config ARM_L1_CACHE_SHIFT
  724. int
  725. default 6 if ARM_L1_CACHE_SHIFT_6
  726. default 5
  727. config ARM_DMA_MEM_BUFFERABLE
  728. bool "Use non-cacheable memory for DMA" if CPU_V6 && !CPU_V7
  729. depends on !(MACH_REALVIEW_PB1176 || REALVIEW_EB_ARM11MP || \
  730. MACH_REALVIEW_PB11MP)
  731. default y if CPU_V6 || CPU_V7
  732. help
  733. Historically, the kernel has used strongly ordered mappings to
  734. provide DMA coherent memory. With the advent of ARMv7, mapping
  735. memory with differing types results in unpredictable behaviour,
  736. so on these CPUs, this option is forced on.
  737. Multiple mappings with differing attributes is also unpredictable
  738. on ARMv6 CPUs, but since they do not have aggressive speculative
  739. prefetch, no harm appears to occur.
  740. However, drivers may be missing the necessary barriers for ARMv6,
  741. and therefore turning this on may result in unpredictable driver
  742. behaviour. Therefore, we offer this as an option.
  743. You are recommended say 'Y' here and debug any affected drivers.
  744. config ARCH_HAS_BARRIERS
  745. bool
  746. help
  747. This option allows the use of custom mandatory barriers
  748. included via the mach/barriers.h file.