Kconfig 68 KB

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  1. # x86 configuration
  2. mainmenu "Linux Kernel Configuration for x86"
  3. # Select 32 or 64 bit
  4. config 64BIT
  5. bool "64-bit kernel" if ARCH = "x86"
  6. default ARCH = "x86_64"
  7. ---help---
  8. Say yes to build a 64-bit kernel - formerly known as x86_64
  9. Say no to build a 32-bit kernel - formerly known as i386
  10. config X86_32
  11. def_bool !64BIT
  12. config X86_64
  13. def_bool 64BIT
  14. ### Arch settings
  15. config X86
  16. def_bool y
  17. select HAVE_AOUT if X86_32
  18. select HAVE_READQ
  19. select HAVE_WRITEQ
  20. select HAVE_UNSTABLE_SCHED_CLOCK
  21. select HAVE_IDE
  22. select HAVE_OPROFILE
  23. select HAVE_PERF_EVENTS if (!M386 && !M486)
  24. select HAVE_IOREMAP_PROT
  25. select HAVE_KPROBES
  26. select ARCH_WANT_OPTIONAL_GPIOLIB
  27. select ARCH_WANT_FRAME_POINTERS
  28. select HAVE_DMA_ATTRS
  29. select HAVE_KRETPROBES
  30. select HAVE_OPTPROBES
  31. select HAVE_FTRACE_MCOUNT_RECORD
  32. select HAVE_DYNAMIC_FTRACE
  33. select HAVE_FUNCTION_TRACER
  34. select HAVE_FUNCTION_GRAPH_TRACER
  35. select HAVE_FUNCTION_GRAPH_FP_TEST
  36. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  37. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  38. select HAVE_SYSCALL_TRACEPOINTS
  39. select HAVE_KVM
  40. select HAVE_ARCH_KGDB
  41. select HAVE_ARCH_TRACEHOOK
  42. select HAVE_GENERIC_DMA_COHERENT if X86_32
  43. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  44. select USER_STACKTRACE_SUPPORT
  45. select HAVE_REGS_AND_STACK_ACCESS_API
  46. select HAVE_DMA_API_DEBUG
  47. select HAVE_KERNEL_GZIP
  48. select HAVE_KERNEL_BZIP2
  49. select HAVE_KERNEL_LZMA
  50. select HAVE_KERNEL_LZO
  51. select HAVE_HW_BREAKPOINT
  52. select HAVE_MIXED_BREAKPOINTS_REGS
  53. select PERF_EVENTS
  54. select HAVE_PERF_EVENTS_NMI
  55. select ANON_INODES
  56. select HAVE_ARCH_KMEMCHECK
  57. select HAVE_USER_RETURN_NOTIFIER
  58. select HAVE_GENERIC_HARDIRQS
  59. select HAVE_SPARSE_IRQ
  60. select NUMA_IRQ_DESC if (SPARSE_IRQ && NUMA)
  61. select GENERIC_IRQ_PROBE
  62. select GENERIC_PENDING_IRQ if SMP
  63. config INSTRUCTION_DECODER
  64. def_bool (KPROBES || PERF_EVENTS)
  65. config OUTPUT_FORMAT
  66. string
  67. default "elf32-i386" if X86_32
  68. default "elf64-x86-64" if X86_64
  69. config ARCH_DEFCONFIG
  70. string
  71. default "arch/x86/configs/i386_defconfig" if X86_32
  72. default "arch/x86/configs/x86_64_defconfig" if X86_64
  73. config GENERIC_CMOS_UPDATE
  74. def_bool y
  75. config CLOCKSOURCE_WATCHDOG
  76. def_bool y
  77. config GENERIC_CLOCKEVENTS
  78. def_bool y
  79. config GENERIC_CLOCKEVENTS_BROADCAST
  80. def_bool y
  81. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  82. config LOCKDEP_SUPPORT
  83. def_bool y
  84. config STACKTRACE_SUPPORT
  85. def_bool y
  86. config HAVE_LATENCYTOP_SUPPORT
  87. def_bool y
  88. config MMU
  89. def_bool y
  90. config ZONE_DMA
  91. def_bool y
  92. config SBUS
  93. bool
  94. config NEED_DMA_MAP_STATE
  95. def_bool (X86_64 || DMAR || DMA_API_DEBUG)
  96. config NEED_SG_DMA_LENGTH
  97. def_bool y
  98. config GENERIC_ISA_DMA
  99. def_bool y
  100. config GENERIC_IOMAP
  101. def_bool y
  102. config GENERIC_BUG
  103. def_bool y
  104. depends on BUG
  105. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  106. config GENERIC_BUG_RELATIVE_POINTERS
  107. bool
  108. config GENERIC_HWEIGHT
  109. def_bool y
  110. config GENERIC_GPIO
  111. bool
  112. config ARCH_MAY_HAVE_PC_FDC
  113. def_bool y
  114. config RWSEM_GENERIC_SPINLOCK
  115. def_bool !X86_XADD
  116. config RWSEM_XCHGADD_ALGORITHM
  117. def_bool X86_XADD
  118. config ARCH_HAS_CPU_IDLE_WAIT
  119. def_bool y
  120. config GENERIC_CALIBRATE_DELAY
  121. def_bool y
  122. config GENERIC_TIME_VSYSCALL
  123. bool
  124. default X86_64
  125. config ARCH_HAS_CPU_RELAX
  126. def_bool y
  127. config ARCH_HAS_DEFAULT_IDLE
  128. def_bool y
  129. config ARCH_HAS_CACHE_LINE_SIZE
  130. def_bool y
  131. config HAVE_SETUP_PER_CPU_AREA
  132. def_bool y
  133. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  134. def_bool y
  135. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  136. def_bool y
  137. config HAVE_CPUMASK_OF_CPU_MAP
  138. def_bool X86_64_SMP
  139. config ARCH_HIBERNATION_POSSIBLE
  140. def_bool y
  141. config ARCH_SUSPEND_POSSIBLE
  142. def_bool y
  143. config ZONE_DMA32
  144. bool
  145. default X86_64
  146. config ARCH_POPULATES_NODE_MAP
  147. def_bool y
  148. config AUDIT_ARCH
  149. bool
  150. default X86_64
  151. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  152. def_bool y
  153. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  154. def_bool y
  155. config HAVE_EARLY_RES
  156. def_bool y
  157. config HAVE_INTEL_TXT
  158. def_bool y
  159. depends on EXPERIMENTAL && DMAR && ACPI
  160. config USE_GENERIC_SMP_HELPERS
  161. def_bool y
  162. depends on SMP
  163. config X86_32_SMP
  164. def_bool y
  165. depends on X86_32 && SMP
  166. config X86_64_SMP
  167. def_bool y
  168. depends on X86_64 && SMP
  169. config X86_HT
  170. def_bool y
  171. depends on SMP
  172. config X86_TRAMPOLINE
  173. def_bool y
  174. depends on SMP || (64BIT && ACPI_SLEEP)
  175. config X86_32_LAZY_GS
  176. def_bool y
  177. depends on X86_32 && !CC_STACKPROTECTOR
  178. config ARCH_HWEIGHT_CFLAGS
  179. string
  180. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  181. default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
  182. config KTIME_SCALAR
  183. def_bool X86_32
  184. config ARCH_CPU_PROBE_RELEASE
  185. def_bool y
  186. depends on HOTPLUG_CPU
  187. source "init/Kconfig"
  188. source "kernel/Kconfig.freezer"
  189. menu "Processor type and features"
  190. source "kernel/time/Kconfig"
  191. config SMP
  192. bool "Symmetric multi-processing support"
  193. ---help---
  194. This enables support for systems with more than one CPU. If you have
  195. a system with only one CPU, like most personal computers, say N. If
  196. you have a system with more than one CPU, say Y.
  197. If you say N here, the kernel will run on single and multiprocessor
  198. machines, but will use only one CPU of a multiprocessor machine. If
  199. you say Y here, the kernel will run on many, but not all,
  200. singleprocessor machines. On a singleprocessor machine, the kernel
  201. will run faster if you say N here.
  202. Note that if you say Y here and choose architecture "586" or
  203. "Pentium" under "Processor family", the kernel will not work on 486
  204. architectures. Similarly, multiprocessor kernels for the "PPro"
  205. architecture may not work on all Pentium based boards.
  206. People using multiprocessor machines who say Y here should also say
  207. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  208. Management" code will be disabled if you say Y here.
  209. See also <file:Documentation/i386/IO-APIC.txt>,
  210. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  211. <http://www.tldp.org/docs.html#howto>.
  212. If you don't know what to do here, say N.
  213. config X86_X2APIC
  214. bool "Support x2apic"
  215. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  216. ---help---
  217. This enables x2apic support on CPUs that have this feature.
  218. This allows 32-bit apic IDs (so it can support very large systems),
  219. and accesses the local apic via MSRs not via mmio.
  220. If you don't know what to do here, say N.
  221. config X86_MPPARSE
  222. bool "Enable MPS table" if ACPI
  223. default y
  224. depends on X86_LOCAL_APIC
  225. ---help---
  226. For old smp systems that do not have proper acpi support. Newer systems
  227. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  228. config X86_BIGSMP
  229. bool "Support for big SMP systems with more than 8 CPUs"
  230. depends on X86_32 && SMP
  231. ---help---
  232. This option is needed for the systems that have more than 8 CPUs
  233. if X86_32
  234. config X86_EXTENDED_PLATFORM
  235. bool "Support for extended (non-PC) x86 platforms"
  236. default y
  237. ---help---
  238. If you disable this option then the kernel will only support
  239. standard PC platforms. (which covers the vast majority of
  240. systems out there.)
  241. If you enable this option then you'll be able to select support
  242. for the following (non-PC) 32 bit x86 platforms:
  243. AMD Elan
  244. NUMAQ (IBM/Sequent)
  245. RDC R-321x SoC
  246. SGI 320/540 (Visual Workstation)
  247. Summit/EXA (IBM x440)
  248. Unisys ES7000 IA32 series
  249. Moorestown MID devices
  250. If you have one of these systems, or if you want to build a
  251. generic distribution kernel, say Y here - otherwise say N.
  252. endif
  253. if X86_64
  254. config X86_EXTENDED_PLATFORM
  255. bool "Support for extended (non-PC) x86 platforms"
  256. default y
  257. ---help---
  258. If you disable this option then the kernel will only support
  259. standard PC platforms. (which covers the vast majority of
  260. systems out there.)
  261. If you enable this option then you'll be able to select support
  262. for the following (non-PC) 64 bit x86 platforms:
  263. ScaleMP vSMP
  264. SGI Ultraviolet
  265. If you have one of these systems, or if you want to build a
  266. generic distribution kernel, say Y here - otherwise say N.
  267. endif
  268. # This is an alphabetically sorted list of 64 bit extended platforms
  269. # Please maintain the alphabetic order if and when there are additions
  270. config X86_VSMP
  271. bool "ScaleMP vSMP"
  272. select PARAVIRT
  273. depends on X86_64 && PCI
  274. depends on X86_EXTENDED_PLATFORM
  275. ---help---
  276. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  277. supposed to run on these EM64T-based machines. Only choose this option
  278. if you have one of these machines.
  279. config X86_UV
  280. bool "SGI Ultraviolet"
  281. depends on X86_64
  282. depends on X86_EXTENDED_PLATFORM
  283. depends on NUMA
  284. depends on X86_X2APIC
  285. ---help---
  286. This option is needed in order to support SGI Ultraviolet systems.
  287. If you don't have one of these, you should say N here.
  288. # Following is an alphabetically sorted list of 32 bit extended platforms
  289. # Please maintain the alphabetic order if and when there are additions
  290. config X86_ELAN
  291. bool "AMD Elan"
  292. depends on X86_32
  293. depends on X86_EXTENDED_PLATFORM
  294. ---help---
  295. Select this for an AMD Elan processor.
  296. Do not use this option for K6/Athlon/Opteron processors!
  297. If unsure, choose "PC-compatible" instead.
  298. config X86_MRST
  299. bool "Moorestown MID platform"
  300. depends on PCI
  301. depends on PCI_GOANY
  302. depends on X86_32
  303. depends on X86_EXTENDED_PLATFORM
  304. depends on X86_IO_APIC
  305. select APB_TIMER
  306. ---help---
  307. Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
  308. Internet Device(MID) platform. Moorestown consists of two chips:
  309. Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
  310. Unlike standard x86 PCs, Moorestown does not have many legacy devices
  311. nor standard legacy replacement devices/features. e.g. Moorestown does
  312. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  313. config X86_RDC321X
  314. bool "RDC R-321x SoC"
  315. depends on X86_32
  316. depends on X86_EXTENDED_PLATFORM
  317. select M486
  318. select X86_REBOOTFIXUPS
  319. ---help---
  320. This option is needed for RDC R-321x system-on-chip, also known
  321. as R-8610-(G).
  322. If you don't have one of these chips, you should say N here.
  323. config X86_32_NON_STANDARD
  324. bool "Support non-standard 32-bit SMP architectures"
  325. depends on X86_32 && SMP
  326. depends on X86_EXTENDED_PLATFORM
  327. ---help---
  328. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  329. subarchitectures. It is intended for a generic binary kernel.
  330. if you select them all, kernel will probe it one by one. and will
  331. fallback to default.
  332. # Alphabetically sorted list of Non standard 32 bit platforms
  333. config X86_NUMAQ
  334. bool "NUMAQ (IBM/Sequent)"
  335. depends on X86_32_NON_STANDARD
  336. depends on PCI
  337. select NUMA
  338. select X86_MPPARSE
  339. ---help---
  340. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  341. NUMA multiquad box. This changes the way that processors are
  342. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  343. of Flat Logical. You will need a new lynxer.elf file to flash your
  344. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  345. config X86_SUPPORTS_MEMORY_FAILURE
  346. def_bool y
  347. # MCE code calls memory_failure():
  348. depends on X86_MCE
  349. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  350. depends on !X86_NUMAQ
  351. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  352. depends on X86_64 || !SPARSEMEM
  353. select ARCH_SUPPORTS_MEMORY_FAILURE
  354. config X86_VISWS
  355. bool "SGI 320/540 (Visual Workstation)"
  356. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  357. depends on X86_32_NON_STANDARD
  358. ---help---
  359. The SGI Visual Workstation series is an IA32-based workstation
  360. based on SGI systems chips with some legacy PC hardware attached.
  361. Say Y here to create a kernel to run on the SGI 320 or 540.
  362. A kernel compiled for the Visual Workstation will run on general
  363. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  364. config X86_SUMMIT
  365. bool "Summit/EXA (IBM x440)"
  366. depends on X86_32_NON_STANDARD
  367. ---help---
  368. This option is needed for IBM systems that use the Summit/EXA chipset.
  369. In particular, it is needed for the x440.
  370. config X86_ES7000
  371. bool "Unisys ES7000 IA32 series"
  372. depends on X86_32_NON_STANDARD && X86_BIGSMP
  373. ---help---
  374. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  375. supposed to run on an IA32-based Unisys ES7000 system.
  376. config SCHED_OMIT_FRAME_POINTER
  377. def_bool y
  378. prompt "Single-depth WCHAN output"
  379. depends on X86
  380. ---help---
  381. Calculate simpler /proc/<PID>/wchan values. If this option
  382. is disabled then wchan values will recurse back to the
  383. caller function. This provides more accurate wchan values,
  384. at the expense of slightly more scheduling overhead.
  385. If in doubt, say "Y".
  386. menuconfig PARAVIRT_GUEST
  387. bool "Paravirtualized guest support"
  388. ---help---
  389. Say Y here to get to see options related to running Linux under
  390. various hypervisors. This option alone does not add any kernel code.
  391. If you say N, all options in this submenu will be skipped and disabled.
  392. if PARAVIRT_GUEST
  393. source "arch/x86/xen/Kconfig"
  394. config VMI
  395. bool "VMI Guest support (DEPRECATED)"
  396. select PARAVIRT
  397. depends on X86_32
  398. ---help---
  399. VMI provides a paravirtualized interface to the VMware ESX server
  400. (it could be used by other hypervisors in theory too, but is not
  401. at the moment), by linking the kernel to a GPL-ed ROM module
  402. provided by the hypervisor.
  403. As of September 2009, VMware has started a phased retirement
  404. of this feature from VMware's products. Please see
  405. feature-removal-schedule.txt for details. If you are
  406. planning to enable this option, please note that you cannot
  407. live migrate a VMI enabled VM to a future VMware product,
  408. which doesn't support VMI. So if you expect your kernel to
  409. seamlessly migrate to newer VMware products, keep this
  410. disabled.
  411. config KVM_CLOCK
  412. bool "KVM paravirtualized clock"
  413. select PARAVIRT
  414. select PARAVIRT_CLOCK
  415. ---help---
  416. Turning on this option will allow you to run a paravirtualized clock
  417. when running over the KVM hypervisor. Instead of relying on a PIT
  418. (or probably other) emulation by the underlying device model, the host
  419. provides the guest with timing infrastructure such as time of day, and
  420. system time
  421. config KVM_GUEST
  422. bool "KVM Guest support"
  423. select PARAVIRT
  424. ---help---
  425. This option enables various optimizations for running under the KVM
  426. hypervisor.
  427. source "arch/x86/lguest/Kconfig"
  428. config PARAVIRT
  429. bool "Enable paravirtualization code"
  430. ---help---
  431. This changes the kernel so it can modify itself when it is run
  432. under a hypervisor, potentially improving performance significantly
  433. over full virtualization. However, when run without a hypervisor
  434. the kernel is theoretically slower and slightly larger.
  435. config PARAVIRT_SPINLOCKS
  436. bool "Paravirtualization layer for spinlocks"
  437. depends on PARAVIRT && SMP && EXPERIMENTAL
  438. ---help---
  439. Paravirtualized spinlocks allow a pvops backend to replace the
  440. spinlock implementation with something virtualization-friendly
  441. (for example, block the virtual CPU rather than spinning).
  442. Unfortunately the downside is an up to 5% performance hit on
  443. native kernels, with various workloads.
  444. If you are unsure how to answer this question, answer N.
  445. config PARAVIRT_CLOCK
  446. bool
  447. endif
  448. config PARAVIRT_DEBUG
  449. bool "paravirt-ops debugging"
  450. depends on PARAVIRT && DEBUG_KERNEL
  451. ---help---
  452. Enable to debug paravirt_ops internals. Specifically, BUG if
  453. a paravirt_op is missing when it is called.
  454. config NO_BOOTMEM
  455. default y
  456. bool "Disable Bootmem code"
  457. ---help---
  458. Use early_res directly instead of bootmem before slab is ready.
  459. - allocator (buddy) [generic]
  460. - early allocator (bootmem) [generic]
  461. - very early allocator (reserve_early*()) [x86]
  462. - very very early allocator (early brk model) [x86]
  463. So reduce one layer between early allocator to final allocator
  464. config MEMTEST
  465. bool "Memtest"
  466. ---help---
  467. This option adds a kernel parameter 'memtest', which allows memtest
  468. to be set.
  469. memtest=0, mean disabled; -- default
  470. memtest=1, mean do 1 test pattern;
  471. ...
  472. memtest=4, mean do 4 test patterns.
  473. If you are unsure how to answer this question, answer N.
  474. config X86_SUMMIT_NUMA
  475. def_bool y
  476. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  477. config X86_CYCLONE_TIMER
  478. def_bool y
  479. depends on X86_32_NON_STANDARD
  480. source "arch/x86/Kconfig.cpu"
  481. config HPET_TIMER
  482. def_bool X86_64
  483. prompt "HPET Timer Support" if X86_32
  484. ---help---
  485. Use the IA-PC HPET (High Precision Event Timer) to manage
  486. time in preference to the PIT and RTC, if a HPET is
  487. present.
  488. HPET is the next generation timer replacing legacy 8254s.
  489. The HPET provides a stable time base on SMP
  490. systems, unlike the TSC, but it is more expensive to access,
  491. as it is off-chip. You can find the HPET spec at
  492. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  493. You can safely choose Y here. However, HPET will only be
  494. activated if the platform and the BIOS support this feature.
  495. Otherwise the 8254 will be used for timing services.
  496. Choose N to continue using the legacy 8254 timer.
  497. config HPET_EMULATE_RTC
  498. def_bool y
  499. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  500. config APB_TIMER
  501. def_bool y if MRST
  502. prompt "Langwell APB Timer Support" if X86_MRST
  503. help
  504. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  505. The APBT provides a stable time base on SMP
  506. systems, unlike the TSC, but it is more expensive to access,
  507. as it is off-chip. APB timers are always running regardless of CPU
  508. C states, they are used as per CPU clockevent device when possible.
  509. # Mark as embedded because too many people got it wrong.
  510. # The code disables itself when not needed.
  511. config DMI
  512. default y
  513. bool "Enable DMI scanning" if EMBEDDED
  514. ---help---
  515. Enabled scanning of DMI to identify machine quirks. Say Y
  516. here unless you have verified that your setup is not
  517. affected by entries in the DMI blacklist. Required by PNP
  518. BIOS code.
  519. config GART_IOMMU
  520. bool "GART IOMMU support" if EMBEDDED
  521. default y
  522. select SWIOTLB
  523. depends on X86_64 && PCI && K8_NB
  524. ---help---
  525. Support for full DMA access of devices with 32bit memory access only
  526. on systems with more than 3GB. This is usually needed for USB,
  527. sound, many IDE/SATA chipsets and some other devices.
  528. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  529. based hardware IOMMU and a software bounce buffer based IOMMU used
  530. on Intel systems and as fallback.
  531. The code is only active when needed (enough memory and limited
  532. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  533. too.
  534. config CALGARY_IOMMU
  535. bool "IBM Calgary IOMMU support"
  536. select SWIOTLB
  537. depends on X86_64 && PCI && EXPERIMENTAL
  538. ---help---
  539. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  540. systems. Needed to run systems with more than 3GB of memory
  541. properly with 32-bit PCI devices that do not support DAC
  542. (Double Address Cycle). Calgary also supports bus level
  543. isolation, where all DMAs pass through the IOMMU. This
  544. prevents them from going anywhere except their intended
  545. destination. This catches hard-to-find kernel bugs and
  546. mis-behaving drivers and devices that do not use the DMA-API
  547. properly to set up their DMA buffers. The IOMMU can be
  548. turned off at boot time with the iommu=off parameter.
  549. Normally the kernel will make the right choice by itself.
  550. If unsure, say Y.
  551. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  552. def_bool y
  553. prompt "Should Calgary be enabled by default?"
  554. depends on CALGARY_IOMMU
  555. ---help---
  556. Should Calgary be enabled by default? if you choose 'y', Calgary
  557. will be used (if it exists). If you choose 'n', Calgary will not be
  558. used even if it exists. If you choose 'n' and would like to use
  559. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  560. If unsure, say Y.
  561. config AMD_IOMMU
  562. bool "AMD IOMMU support"
  563. select SWIOTLB
  564. select PCI_MSI
  565. depends on X86_64 && PCI && ACPI
  566. ---help---
  567. With this option you can enable support for AMD IOMMU hardware in
  568. your system. An IOMMU is a hardware component which provides
  569. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  570. can isolate the the DMA memory of different devices and protect the
  571. system from misbehaving device drivers or hardware.
  572. You can find out if your system has an AMD IOMMU if you look into
  573. your BIOS for an option to enable it or if you have an IVRS ACPI
  574. table.
  575. config AMD_IOMMU_STATS
  576. bool "Export AMD IOMMU statistics to debugfs"
  577. depends on AMD_IOMMU
  578. select DEBUG_FS
  579. ---help---
  580. This option enables code in the AMD IOMMU driver to collect various
  581. statistics about whats happening in the driver and exports that
  582. information to userspace via debugfs.
  583. If unsure, say N.
  584. # need this always selected by IOMMU for the VIA workaround
  585. config SWIOTLB
  586. def_bool y if X86_64
  587. ---help---
  588. Support for software bounce buffers used on x86-64 systems
  589. which don't have a hardware IOMMU (e.g. the current generation
  590. of Intel's x86-64 CPUs). Using this PCI devices which can only
  591. access 32-bits of memory can be used on systems with more than
  592. 3 GB of memory. If unsure, say Y.
  593. config IOMMU_HELPER
  594. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  595. config IOMMU_API
  596. def_bool (AMD_IOMMU || DMAR)
  597. config MAXSMP
  598. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  599. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  600. select CPUMASK_OFFSTACK
  601. ---help---
  602. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  603. If unsure, say N.
  604. config NR_CPUS
  605. int "Maximum number of CPUs" if SMP && !MAXSMP
  606. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  607. range 2 512 if SMP && !MAXSMP
  608. default "1" if !SMP
  609. default "4096" if MAXSMP
  610. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  611. default "8" if SMP
  612. ---help---
  613. This allows you to specify the maximum number of CPUs which this
  614. kernel will support. The maximum supported value is 512 and the
  615. minimum value which makes sense is 2.
  616. This is purely to save memory - each supported CPU adds
  617. approximately eight kilobytes to the kernel image.
  618. config SCHED_SMT
  619. bool "SMT (Hyperthreading) scheduler support"
  620. depends on X86_HT
  621. ---help---
  622. SMT scheduler support improves the CPU scheduler's decision making
  623. when dealing with Intel Pentium 4 chips with HyperThreading at a
  624. cost of slightly increased overhead in some places. If unsure say
  625. N here.
  626. config SCHED_MC
  627. def_bool y
  628. prompt "Multi-core scheduler support"
  629. depends on X86_HT
  630. ---help---
  631. Multi-core scheduler support improves the CPU scheduler's decision
  632. making when dealing with multi-core CPU chips at a cost of slightly
  633. increased overhead in some places. If unsure say N here.
  634. source "kernel/Kconfig.preempt"
  635. config X86_UP_APIC
  636. bool "Local APIC support on uniprocessors"
  637. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  638. ---help---
  639. A local APIC (Advanced Programmable Interrupt Controller) is an
  640. integrated interrupt controller in the CPU. If you have a single-CPU
  641. system which has a processor with a local APIC, you can say Y here to
  642. enable and use it. If you say Y here even though your machine doesn't
  643. have a local APIC, then the kernel will still run with no slowdown at
  644. all. The local APIC supports CPU-generated self-interrupts (timer,
  645. performance counters), and the NMI watchdog which detects hard
  646. lockups.
  647. config X86_UP_IOAPIC
  648. bool "IO-APIC support on uniprocessors"
  649. depends on X86_UP_APIC
  650. ---help---
  651. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  652. SMP-capable replacement for PC-style interrupt controllers. Most
  653. SMP systems and many recent uniprocessor systems have one.
  654. If you have a single-CPU system with an IO-APIC, you can say Y here
  655. to use it. If you say Y here even though your machine doesn't have
  656. an IO-APIC, then the kernel will still run with no slowdown at all.
  657. config X86_LOCAL_APIC
  658. def_bool y
  659. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  660. config X86_IO_APIC
  661. def_bool y
  662. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  663. config X86_VISWS_APIC
  664. def_bool y
  665. depends on X86_32 && X86_VISWS
  666. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  667. bool "Reroute for broken boot IRQs"
  668. depends on X86_IO_APIC
  669. ---help---
  670. This option enables a workaround that fixes a source of
  671. spurious interrupts. This is recommended when threaded
  672. interrupt handling is used on systems where the generation of
  673. superfluous "boot interrupts" cannot be disabled.
  674. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  675. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  676. kernel does during interrupt handling). On chipsets where this
  677. boot IRQ generation cannot be disabled, this workaround keeps
  678. the original IRQ line masked so that only the equivalent "boot
  679. IRQ" is delivered to the CPUs. The workaround also tells the
  680. kernel to set up the IRQ handler on the boot IRQ line. In this
  681. way only one interrupt is delivered to the kernel. Otherwise
  682. the spurious second interrupt may cause the kernel to bring
  683. down (vital) interrupt lines.
  684. Only affects "broken" chipsets. Interrupt sharing may be
  685. increased on these systems.
  686. config X86_MCE
  687. bool "Machine Check / overheating reporting"
  688. ---help---
  689. Machine Check support allows the processor to notify the
  690. kernel if it detects a problem (e.g. overheating, data corruption).
  691. The action the kernel takes depends on the severity of the problem,
  692. ranging from warning messages to halting the machine.
  693. config X86_MCE_INTEL
  694. def_bool y
  695. prompt "Intel MCE features"
  696. depends on X86_MCE && X86_LOCAL_APIC
  697. ---help---
  698. Additional support for intel specific MCE features such as
  699. the thermal monitor.
  700. config X86_MCE_AMD
  701. def_bool y
  702. prompt "AMD MCE features"
  703. depends on X86_MCE && X86_LOCAL_APIC
  704. ---help---
  705. Additional support for AMD specific MCE features such as
  706. the DRAM Error Threshold.
  707. config X86_ANCIENT_MCE
  708. bool "Support for old Pentium 5 / WinChip machine checks"
  709. depends on X86_32 && X86_MCE
  710. ---help---
  711. Include support for machine check handling on old Pentium 5 or WinChip
  712. systems. These typically need to be enabled explicitely on the command
  713. line.
  714. config X86_MCE_THRESHOLD
  715. depends on X86_MCE_AMD || X86_MCE_INTEL
  716. def_bool y
  717. config X86_MCE_INJECT
  718. depends on X86_MCE
  719. tristate "Machine check injector support"
  720. ---help---
  721. Provide support for injecting machine checks for testing purposes.
  722. If you don't know what a machine check is and you don't do kernel
  723. QA it is safe to say n.
  724. config X86_THERMAL_VECTOR
  725. def_bool y
  726. depends on X86_MCE_INTEL
  727. config VM86
  728. bool "Enable VM86 support" if EMBEDDED
  729. default y
  730. depends on X86_32
  731. ---help---
  732. This option is required by programs like DOSEMU to run 16-bit legacy
  733. code on X86 processors. It also may be needed by software like
  734. XFree86 to initialize some video cards via BIOS. Disabling this
  735. option saves about 6k.
  736. config TOSHIBA
  737. tristate "Toshiba Laptop support"
  738. depends on X86_32
  739. ---help---
  740. This adds a driver to safely access the System Management Mode of
  741. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  742. not work on models with a Phoenix BIOS. The System Management Mode
  743. is used to set the BIOS and power saving options on Toshiba portables.
  744. For information on utilities to make use of this driver see the
  745. Toshiba Linux utilities web site at:
  746. <http://www.buzzard.org.uk/toshiba/>.
  747. Say Y if you intend to run this kernel on a Toshiba portable.
  748. Say N otherwise.
  749. config I8K
  750. tristate "Dell laptop support"
  751. ---help---
  752. This adds a driver to safely access the System Management Mode
  753. of the CPU on the Dell Inspiron 8000. The System Management Mode
  754. is used to read cpu temperature and cooling fan status and to
  755. control the fans on the I8K portables.
  756. This driver has been tested only on the Inspiron 8000 but it may
  757. also work with other Dell laptops. You can force loading on other
  758. models by passing the parameter `force=1' to the module. Use at
  759. your own risk.
  760. For information on utilities to make use of this driver see the
  761. I8K Linux utilities web site at:
  762. <http://people.debian.org/~dz/i8k/>
  763. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  764. Say N otherwise.
  765. config X86_REBOOTFIXUPS
  766. bool "Enable X86 board specific fixups for reboot"
  767. depends on X86_32
  768. ---help---
  769. This enables chipset and/or board specific fixups to be done
  770. in order to get reboot to work correctly. This is only needed on
  771. some combinations of hardware and BIOS. The symptom, for which
  772. this config is intended, is when reboot ends with a stalled/hung
  773. system.
  774. Currently, the only fixup is for the Geode machines using
  775. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  776. Say Y if you want to enable the fixup. Currently, it's safe to
  777. enable this option even if you don't need it.
  778. Say N otherwise.
  779. config MICROCODE
  780. tristate "/dev/cpu/microcode - microcode support"
  781. select FW_LOADER
  782. ---help---
  783. If you say Y here, you will be able to update the microcode on
  784. certain Intel and AMD processors. The Intel support is for the
  785. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  786. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  787. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  788. You will obviously need the actual microcode binary data itself
  789. which is not shipped with the Linux kernel.
  790. This option selects the general module only, you need to select
  791. at least one vendor specific module as well.
  792. To compile this driver as a module, choose M here: the
  793. module will be called microcode.
  794. config MICROCODE_INTEL
  795. bool "Intel microcode patch loading support"
  796. depends on MICROCODE
  797. default MICROCODE
  798. select FW_LOADER
  799. ---help---
  800. This options enables microcode patch loading support for Intel
  801. processors.
  802. For latest news and information on obtaining all the required
  803. Intel ingredients for this driver, check:
  804. <http://www.urbanmyth.org/microcode/>.
  805. config MICROCODE_AMD
  806. bool "AMD microcode patch loading support"
  807. depends on MICROCODE
  808. select FW_LOADER
  809. ---help---
  810. If you select this option, microcode patch loading support for AMD
  811. processors will be enabled.
  812. config MICROCODE_OLD_INTERFACE
  813. def_bool y
  814. depends on MICROCODE
  815. config X86_MSR
  816. tristate "/dev/cpu/*/msr - Model-specific register support"
  817. ---help---
  818. This device gives privileged processes access to the x86
  819. Model-Specific Registers (MSRs). It is a character device with
  820. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  821. MSR accesses are directed to a specific CPU on multi-processor
  822. systems.
  823. config X86_CPUID
  824. tristate "/dev/cpu/*/cpuid - CPU information support"
  825. ---help---
  826. This device gives processes access to the x86 CPUID instruction to
  827. be executed on a specific processor. It is a character device
  828. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  829. /dev/cpu/31/cpuid.
  830. choice
  831. prompt "High Memory Support"
  832. default HIGHMEM64G if X86_NUMAQ
  833. default HIGHMEM4G
  834. depends on X86_32
  835. config NOHIGHMEM
  836. bool "off"
  837. depends on !X86_NUMAQ
  838. ---help---
  839. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  840. However, the address space of 32-bit x86 processors is only 4
  841. Gigabytes large. That means that, if you have a large amount of
  842. physical memory, not all of it can be "permanently mapped" by the
  843. kernel. The physical memory that's not permanently mapped is called
  844. "high memory".
  845. If you are compiling a kernel which will never run on a machine with
  846. more than 1 Gigabyte total physical RAM, answer "off" here (default
  847. choice and suitable for most users). This will result in a "3GB/1GB"
  848. split: 3GB are mapped so that each process sees a 3GB virtual memory
  849. space and the remaining part of the 4GB virtual memory space is used
  850. by the kernel to permanently map as much physical memory as
  851. possible.
  852. If the machine has between 1 and 4 Gigabytes physical RAM, then
  853. answer "4GB" here.
  854. If more than 4 Gigabytes is used then answer "64GB" here. This
  855. selection turns Intel PAE (Physical Address Extension) mode on.
  856. PAE implements 3-level paging on IA32 processors. PAE is fully
  857. supported by Linux, PAE mode is implemented on all recent Intel
  858. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  859. then the kernel will not boot on CPUs that don't support PAE!
  860. The actual amount of total physical memory will either be
  861. auto detected or can be forced by using a kernel command line option
  862. such as "mem=256M". (Try "man bootparam" or see the documentation of
  863. your boot loader (lilo or loadlin) about how to pass options to the
  864. kernel at boot time.)
  865. If unsure, say "off".
  866. config HIGHMEM4G
  867. bool "4GB"
  868. depends on !X86_NUMAQ
  869. ---help---
  870. Select this if you have a 32-bit processor and between 1 and 4
  871. gigabytes of physical RAM.
  872. config HIGHMEM64G
  873. bool "64GB"
  874. depends on !M386 && !M486
  875. select X86_PAE
  876. ---help---
  877. Select this if you have a 32-bit processor and more than 4
  878. gigabytes of physical RAM.
  879. endchoice
  880. choice
  881. depends on EXPERIMENTAL
  882. prompt "Memory split" if EMBEDDED
  883. default VMSPLIT_3G
  884. depends on X86_32
  885. ---help---
  886. Select the desired split between kernel and user memory.
  887. If the address range available to the kernel is less than the
  888. physical memory installed, the remaining memory will be available
  889. as "high memory". Accessing high memory is a little more costly
  890. than low memory, as it needs to be mapped into the kernel first.
  891. Note that increasing the kernel address space limits the range
  892. available to user programs, making the address space there
  893. tighter. Selecting anything other than the default 3G/1G split
  894. will also likely make your kernel incompatible with binary-only
  895. kernel modules.
  896. If you are not absolutely sure what you are doing, leave this
  897. option alone!
  898. config VMSPLIT_3G
  899. bool "3G/1G user/kernel split"
  900. config VMSPLIT_3G_OPT
  901. depends on !X86_PAE
  902. bool "3G/1G user/kernel split (for full 1G low memory)"
  903. config VMSPLIT_2G
  904. bool "2G/2G user/kernel split"
  905. config VMSPLIT_2G_OPT
  906. depends on !X86_PAE
  907. bool "2G/2G user/kernel split (for full 2G low memory)"
  908. config VMSPLIT_1G
  909. bool "1G/3G user/kernel split"
  910. endchoice
  911. config PAGE_OFFSET
  912. hex
  913. default 0xB0000000 if VMSPLIT_3G_OPT
  914. default 0x80000000 if VMSPLIT_2G
  915. default 0x78000000 if VMSPLIT_2G_OPT
  916. default 0x40000000 if VMSPLIT_1G
  917. default 0xC0000000
  918. depends on X86_32
  919. config HIGHMEM
  920. def_bool y
  921. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  922. config X86_PAE
  923. bool "PAE (Physical Address Extension) Support"
  924. depends on X86_32 && !HIGHMEM4G
  925. ---help---
  926. PAE is required for NX support, and furthermore enables
  927. larger swapspace support for non-overcommit purposes. It
  928. has the cost of more pagetable lookup overhead, and also
  929. consumes more pagetable space per process.
  930. config ARCH_PHYS_ADDR_T_64BIT
  931. def_bool X86_64 || X86_PAE
  932. config DIRECT_GBPAGES
  933. bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
  934. default y
  935. depends on X86_64
  936. ---help---
  937. Allow the kernel linear mapping to use 1GB pages on CPUs that
  938. support it. This can improve the kernel's performance a tiny bit by
  939. reducing TLB pressure. If in doubt, say "Y".
  940. # Common NUMA Features
  941. config NUMA
  942. bool "Numa Memory Allocation and Scheduler Support"
  943. depends on SMP
  944. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  945. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  946. ---help---
  947. Enable NUMA (Non Uniform Memory Access) support.
  948. The kernel will try to allocate memory used by a CPU on the
  949. local memory controller of the CPU and add some more
  950. NUMA awareness to the kernel.
  951. For 64-bit this is recommended if the system is Intel Core i7
  952. (or later), AMD Opteron, or EM64T NUMA.
  953. For 32-bit this is only needed on (rare) 32-bit-only platforms
  954. that support NUMA topologies, such as NUMAQ / Summit, or if you
  955. boot a 32-bit kernel on a 64-bit NUMA platform.
  956. Otherwise, you should say N.
  957. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  958. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  959. config K8_NUMA
  960. def_bool y
  961. prompt "Old style AMD Opteron NUMA detection"
  962. depends on X86_64 && NUMA && PCI
  963. ---help---
  964. Enable K8 NUMA node topology detection. You should say Y here if
  965. you have a multi processor AMD K8 system. This uses an old
  966. method to read the NUMA configuration directly from the builtin
  967. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  968. instead, which also takes priority if both are compiled in.
  969. config X86_64_ACPI_NUMA
  970. def_bool y
  971. prompt "ACPI NUMA detection"
  972. depends on X86_64 && NUMA && ACPI && PCI
  973. select ACPI_NUMA
  974. ---help---
  975. Enable ACPI SRAT based node topology detection.
  976. # Some NUMA nodes have memory ranges that span
  977. # other nodes. Even though a pfn is valid and
  978. # between a node's start and end pfns, it may not
  979. # reside on that node. See memmap_init_zone()
  980. # for details.
  981. config NODES_SPAN_OTHER_NODES
  982. def_bool y
  983. depends on X86_64_ACPI_NUMA
  984. config NUMA_EMU
  985. bool "NUMA emulation"
  986. depends on X86_64 && NUMA
  987. ---help---
  988. Enable NUMA emulation. A flat machine will be split
  989. into virtual nodes when booted with "numa=fake=N", where N is the
  990. number of nodes. This is only useful for debugging.
  991. config NODES_SHIFT
  992. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  993. range 1 10
  994. default "10" if MAXSMP
  995. default "6" if X86_64
  996. default "4" if X86_NUMAQ
  997. default "3"
  998. depends on NEED_MULTIPLE_NODES
  999. ---help---
  1000. Specify the maximum number of NUMA Nodes available on the target
  1001. system. Increases memory reserved to accommodate various tables.
  1002. config HAVE_ARCH_BOOTMEM
  1003. def_bool y
  1004. depends on X86_32 && NUMA
  1005. config ARCH_HAVE_MEMORY_PRESENT
  1006. def_bool y
  1007. depends on X86_32 && DISCONTIGMEM
  1008. config NEED_NODE_MEMMAP_SIZE
  1009. def_bool y
  1010. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1011. config HAVE_ARCH_ALLOC_REMAP
  1012. def_bool y
  1013. depends on X86_32 && NUMA
  1014. config ARCH_FLATMEM_ENABLE
  1015. def_bool y
  1016. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
  1017. config ARCH_DISCONTIGMEM_ENABLE
  1018. def_bool y
  1019. depends on NUMA && X86_32
  1020. config ARCH_DISCONTIGMEM_DEFAULT
  1021. def_bool y
  1022. depends on NUMA && X86_32
  1023. config ARCH_PROC_KCORE_TEXT
  1024. def_bool y
  1025. depends on X86_64 && PROC_KCORE
  1026. config ARCH_SPARSEMEM_DEFAULT
  1027. def_bool y
  1028. depends on X86_64
  1029. config ARCH_SPARSEMEM_ENABLE
  1030. def_bool y
  1031. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1032. select SPARSEMEM_STATIC if X86_32
  1033. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1034. config ARCH_SELECT_MEMORY_MODEL
  1035. def_bool y
  1036. depends on ARCH_SPARSEMEM_ENABLE
  1037. config ARCH_MEMORY_PROBE
  1038. def_bool X86_64
  1039. depends on MEMORY_HOTPLUG
  1040. config ILLEGAL_POINTER_VALUE
  1041. hex
  1042. default 0 if X86_32
  1043. default 0xdead000000000000 if X86_64
  1044. source "mm/Kconfig"
  1045. config HIGHPTE
  1046. bool "Allocate 3rd-level pagetables from highmem"
  1047. depends on HIGHMEM
  1048. ---help---
  1049. The VM uses one page table entry for each page of physical memory.
  1050. For systems with a lot of RAM, this can be wasteful of precious
  1051. low memory. Setting this option will put user-space page table
  1052. entries in high memory.
  1053. config X86_CHECK_BIOS_CORRUPTION
  1054. bool "Check for low memory corruption"
  1055. ---help---
  1056. Periodically check for memory corruption in low memory, which
  1057. is suspected to be caused by BIOS. Even when enabled in the
  1058. configuration, it is disabled at runtime. Enable it by
  1059. setting "memory_corruption_check=1" on the kernel command
  1060. line. By default it scans the low 64k of memory every 60
  1061. seconds; see the memory_corruption_check_size and
  1062. memory_corruption_check_period parameters in
  1063. Documentation/kernel-parameters.txt to adjust this.
  1064. When enabled with the default parameters, this option has
  1065. almost no overhead, as it reserves a relatively small amount
  1066. of memory and scans it infrequently. It both detects corruption
  1067. and prevents it from affecting the running system.
  1068. It is, however, intended as a diagnostic tool; if repeatable
  1069. BIOS-originated corruption always affects the same memory,
  1070. you can use memmap= to prevent the kernel from using that
  1071. memory.
  1072. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1073. bool "Set the default setting of memory_corruption_check"
  1074. depends on X86_CHECK_BIOS_CORRUPTION
  1075. default y
  1076. ---help---
  1077. Set whether the default state of memory_corruption_check is
  1078. on or off.
  1079. config X86_RESERVE_LOW_64K
  1080. bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
  1081. default y
  1082. ---help---
  1083. Reserve the first 64K of physical RAM on BIOSes that are known
  1084. to potentially corrupt that memory range. A numbers of BIOSes are
  1085. known to utilize this area during suspend/resume, so it must not
  1086. be used by the kernel.
  1087. Set this to N if you are absolutely sure that you trust the BIOS
  1088. to get all its memory reservations and usages right.
  1089. If you have doubts about the BIOS (e.g. suspend/resume does not
  1090. work or there's kernel crashes after certain hardware hotplug
  1091. events) and it's not AMI or Phoenix, then you might want to enable
  1092. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
  1093. corruption patterns.
  1094. Say Y if unsure.
  1095. config MATH_EMULATION
  1096. bool
  1097. prompt "Math emulation" if X86_32
  1098. ---help---
  1099. Linux can emulate a math coprocessor (used for floating point
  1100. operations) if you don't have one. 486DX and Pentium processors have
  1101. a math coprocessor built in, 486SX and 386 do not, unless you added
  1102. a 487DX or 387, respectively. (The messages during boot time can
  1103. give you some hints here ["man dmesg"].) Everyone needs either a
  1104. coprocessor or this emulation.
  1105. If you don't have a math coprocessor, you need to say Y here; if you
  1106. say Y here even though you have a coprocessor, the coprocessor will
  1107. be used nevertheless. (This behavior can be changed with the kernel
  1108. command line option "no387", which comes handy if your coprocessor
  1109. is broken. Try "man bootparam" or see the documentation of your boot
  1110. loader (lilo or loadlin) about how to pass options to the kernel at
  1111. boot time.) This means that it is a good idea to say Y here if you
  1112. intend to use this kernel on different machines.
  1113. More information about the internals of the Linux math coprocessor
  1114. emulation can be found in <file:arch/x86/math-emu/README>.
  1115. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1116. kernel, it won't hurt.
  1117. config MTRR
  1118. def_bool y
  1119. prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
  1120. ---help---
  1121. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1122. the Memory Type Range Registers (MTRRs) may be used to control
  1123. processor access to memory ranges. This is most useful if you have
  1124. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1125. allows bus write transfers to be combined into a larger transfer
  1126. before bursting over the PCI/AGP bus. This can increase performance
  1127. of image write operations 2.5 times or more. Saying Y here creates a
  1128. /proc/mtrr file which may be used to manipulate your processor's
  1129. MTRRs. Typically the X server should use this.
  1130. This code has a reasonably generic interface so that similar
  1131. control registers on other processors can be easily supported
  1132. as well:
  1133. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1134. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1135. these, the ARRs are used to emulate the MTRRs.
  1136. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1137. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1138. write-combining. All of these processors are supported by this code
  1139. and it makes sense to say Y here if you have one of them.
  1140. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1141. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1142. can lead to all sorts of problems, so it's good to say Y here.
  1143. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1144. just add about 9 KB to your kernel.
  1145. See <file:Documentation/x86/mtrr.txt> for more information.
  1146. config MTRR_SANITIZER
  1147. def_bool y
  1148. prompt "MTRR cleanup support"
  1149. depends on MTRR
  1150. ---help---
  1151. Convert MTRR layout from continuous to discrete, so X drivers can
  1152. add writeback entries.
  1153. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1154. The largest mtrr entry size for a continuous block can be set with
  1155. mtrr_chunk_size.
  1156. If unsure, say Y.
  1157. config MTRR_SANITIZER_ENABLE_DEFAULT
  1158. int "MTRR cleanup enable value (0-1)"
  1159. range 0 1
  1160. default "0"
  1161. depends on MTRR_SANITIZER
  1162. ---help---
  1163. Enable mtrr cleanup default value
  1164. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1165. int "MTRR cleanup spare reg num (0-7)"
  1166. range 0 7
  1167. default "1"
  1168. depends on MTRR_SANITIZER
  1169. ---help---
  1170. mtrr cleanup spare entries default, it can be changed via
  1171. mtrr_spare_reg_nr=N on the kernel command line.
  1172. config X86_PAT
  1173. def_bool y
  1174. prompt "x86 PAT support" if EMBEDDED
  1175. depends on MTRR
  1176. ---help---
  1177. Use PAT attributes to setup page level cache control.
  1178. PATs are the modern equivalents of MTRRs and are much more
  1179. flexible than MTRRs.
  1180. Say N here if you see bootup problems (boot crash, boot hang,
  1181. spontaneous reboots) or a non-working video driver.
  1182. If unsure, say Y.
  1183. config ARCH_USES_PG_UNCACHED
  1184. def_bool y
  1185. depends on X86_PAT
  1186. config EFI
  1187. bool "EFI runtime service support"
  1188. depends on ACPI
  1189. ---help---
  1190. This enables the kernel to use EFI runtime services that are
  1191. available (such as the EFI variable services).
  1192. This option is only useful on systems that have EFI firmware.
  1193. In addition, you should use the latest ELILO loader available
  1194. at <http://elilo.sourceforge.net> in order to take advantage
  1195. of EFI runtime services. However, even with this option, the
  1196. resultant kernel should continue to boot on existing non-EFI
  1197. platforms.
  1198. config SECCOMP
  1199. def_bool y
  1200. prompt "Enable seccomp to safely compute untrusted bytecode"
  1201. ---help---
  1202. This kernel feature is useful for number crunching applications
  1203. that may need to compute untrusted bytecode during their
  1204. execution. By using pipes or other transports made available to
  1205. the process as file descriptors supporting the read/write
  1206. syscalls, it's possible to isolate those applications in
  1207. their own address space using seccomp. Once seccomp is
  1208. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1209. and the task is only allowed to execute a few safe syscalls
  1210. defined by each seccomp mode.
  1211. If unsure, say Y. Only embedded should say N here.
  1212. config CC_STACKPROTECTOR
  1213. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1214. ---help---
  1215. This option turns on the -fstack-protector GCC feature. This
  1216. feature puts, at the beginning of functions, a canary value on
  1217. the stack just before the return address, and validates
  1218. the value just before actually returning. Stack based buffer
  1219. overflows (that need to overwrite this return address) now also
  1220. overwrite the canary, which gets detected and the attack is then
  1221. neutralized via a kernel panic.
  1222. This feature requires gcc version 4.2 or above, or a distribution
  1223. gcc with the feature backported. Older versions are automatically
  1224. detected and for those versions, this configuration option is
  1225. ignored. (and a warning is printed during bootup)
  1226. source kernel/Kconfig.hz
  1227. config KEXEC
  1228. bool "kexec system call"
  1229. ---help---
  1230. kexec is a system call that implements the ability to shutdown your
  1231. current kernel, and to start another kernel. It is like a reboot
  1232. but it is independent of the system firmware. And like a reboot
  1233. you can start any kernel with it, not just Linux.
  1234. The name comes from the similarity to the exec system call.
  1235. It is an ongoing process to be certain the hardware in a machine
  1236. is properly shutdown, so do not be surprised if this code does not
  1237. initially work for you. It may help to enable device hotplugging
  1238. support. As of this writing the exact hardware interface is
  1239. strongly in flux, so no good recommendation can be made.
  1240. config CRASH_DUMP
  1241. bool "kernel crash dumps"
  1242. depends on X86_64 || (X86_32 && HIGHMEM)
  1243. ---help---
  1244. Generate crash dump after being started by kexec.
  1245. This should be normally only set in special crash dump kernels
  1246. which are loaded in the main kernel with kexec-tools into
  1247. a specially reserved region and then later executed after
  1248. a crash by kdump/kexec. The crash dump kernel must be compiled
  1249. to a memory address not used by the main kernel or BIOS using
  1250. PHYSICAL_START, or it must be built as a relocatable image
  1251. (CONFIG_RELOCATABLE=y).
  1252. For more details see Documentation/kdump/kdump.txt
  1253. config KEXEC_JUMP
  1254. bool "kexec jump (EXPERIMENTAL)"
  1255. depends on EXPERIMENTAL
  1256. depends on KEXEC && HIBERNATION
  1257. ---help---
  1258. Jump between original kernel and kexeced kernel and invoke
  1259. code in physical address mode via KEXEC
  1260. config PHYSICAL_START
  1261. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1262. default "0x1000000"
  1263. ---help---
  1264. This gives the physical address where the kernel is loaded.
  1265. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1266. bzImage will decompress itself to above physical address and
  1267. run from there. Otherwise, bzImage will run from the address where
  1268. it has been loaded by the boot loader and will ignore above physical
  1269. address.
  1270. In normal kdump cases one does not have to set/change this option
  1271. as now bzImage can be compiled as a completely relocatable image
  1272. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1273. address. This option is mainly useful for the folks who don't want
  1274. to use a bzImage for capturing the crash dump and want to use a
  1275. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1276. to be specifically compiled to run from a specific memory area
  1277. (normally a reserved region) and this option comes handy.
  1278. So if you are using bzImage for capturing the crash dump,
  1279. leave the value here unchanged to 0x1000000 and set
  1280. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1281. for capturing the crash dump change this value to start of
  1282. the reserved region. In other words, it can be set based on
  1283. the "X" value as specified in the "crashkernel=YM@XM"
  1284. command line boot parameter passed to the panic-ed
  1285. kernel. Please take a look at Documentation/kdump/kdump.txt
  1286. for more details about crash dumps.
  1287. Usage of bzImage for capturing the crash dump is recommended as
  1288. one does not have to build two kernels. Same kernel can be used
  1289. as production kernel and capture kernel. Above option should have
  1290. gone away after relocatable bzImage support is introduced. But it
  1291. is present because there are users out there who continue to use
  1292. vmlinux for dump capture. This option should go away down the
  1293. line.
  1294. Don't change this unless you know what you are doing.
  1295. config RELOCATABLE
  1296. bool "Build a relocatable kernel"
  1297. default y
  1298. ---help---
  1299. This builds a kernel image that retains relocation information
  1300. so it can be loaded someplace besides the default 1MB.
  1301. The relocations tend to make the kernel binary about 10% larger,
  1302. but are discarded at runtime.
  1303. One use is for the kexec on panic case where the recovery kernel
  1304. must live at a different physical address than the primary
  1305. kernel.
  1306. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1307. it has been loaded at and the compile time physical address
  1308. (CONFIG_PHYSICAL_START) is ignored.
  1309. # Relocation on x86-32 needs some additional build support
  1310. config X86_NEED_RELOCS
  1311. def_bool y
  1312. depends on X86_32 && RELOCATABLE
  1313. config PHYSICAL_ALIGN
  1314. hex "Alignment value to which kernel should be aligned" if X86_32
  1315. default "0x1000000"
  1316. range 0x2000 0x1000000
  1317. ---help---
  1318. This value puts the alignment restrictions on physical address
  1319. where kernel is loaded and run from. Kernel is compiled for an
  1320. address which meets above alignment restriction.
  1321. If bootloader loads the kernel at a non-aligned address and
  1322. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1323. address aligned to above value and run from there.
  1324. If bootloader loads the kernel at a non-aligned address and
  1325. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1326. load address and decompress itself to the address it has been
  1327. compiled for and run from there. The address for which kernel is
  1328. compiled already meets above alignment restrictions. Hence the
  1329. end result is that kernel runs from a physical address meeting
  1330. above alignment restrictions.
  1331. Don't change this unless you know what you are doing.
  1332. config HOTPLUG_CPU
  1333. bool "Support for hot-pluggable CPUs"
  1334. depends on SMP && HOTPLUG
  1335. ---help---
  1336. Say Y here to allow turning CPUs off and on. CPUs can be
  1337. controlled through /sys/devices/system/cpu.
  1338. ( Note: power management support will enable this option
  1339. automatically on SMP systems. )
  1340. Say N if you want to disable CPU hotplug.
  1341. config COMPAT_VDSO
  1342. def_bool y
  1343. prompt "Compat VDSO support"
  1344. depends on X86_32 || IA32_EMULATION
  1345. ---help---
  1346. Map the 32-bit VDSO to the predictable old-style address too.
  1347. Say N here if you are running a sufficiently recent glibc
  1348. version (2.3.3 or later), to remove the high-mapped
  1349. VDSO mapping and to exclusively use the randomized VDSO.
  1350. If unsure, say Y.
  1351. config CMDLINE_BOOL
  1352. bool "Built-in kernel command line"
  1353. ---help---
  1354. Allow for specifying boot arguments to the kernel at
  1355. build time. On some systems (e.g. embedded ones), it is
  1356. necessary or convenient to provide some or all of the
  1357. kernel boot arguments with the kernel itself (that is,
  1358. to not rely on the boot loader to provide them.)
  1359. To compile command line arguments into the kernel,
  1360. set this option to 'Y', then fill in the
  1361. the boot arguments in CONFIG_CMDLINE.
  1362. Systems with fully functional boot loaders (i.e. non-embedded)
  1363. should leave this option set to 'N'.
  1364. config CMDLINE
  1365. string "Built-in kernel command string"
  1366. depends on CMDLINE_BOOL
  1367. default ""
  1368. ---help---
  1369. Enter arguments here that should be compiled into the kernel
  1370. image and used at boot time. If the boot loader provides a
  1371. command line at boot time, it is appended to this string to
  1372. form the full kernel command line, when the system boots.
  1373. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1374. change this behavior.
  1375. In most cases, the command line (whether built-in or provided
  1376. by the boot loader) should specify the device for the root
  1377. file system.
  1378. config CMDLINE_OVERRIDE
  1379. bool "Built-in command line overrides boot loader arguments"
  1380. depends on CMDLINE_BOOL
  1381. ---help---
  1382. Set this option to 'Y' to have the kernel ignore the boot loader
  1383. command line, and use ONLY the built-in command line.
  1384. This is used to work around broken boot loaders. This should
  1385. be set to 'N' under normal conditions.
  1386. endmenu
  1387. config ARCH_ENABLE_MEMORY_HOTPLUG
  1388. def_bool y
  1389. depends on X86_64 || (X86_32 && HIGHMEM)
  1390. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1391. def_bool y
  1392. depends on MEMORY_HOTPLUG
  1393. config HAVE_ARCH_EARLY_PFN_TO_NID
  1394. def_bool X86_64
  1395. depends on NUMA
  1396. config USE_PERCPU_NUMA_NODE_ID
  1397. def_bool X86_64
  1398. depends on NUMA
  1399. menu "Power management and ACPI options"
  1400. config ARCH_HIBERNATION_HEADER
  1401. def_bool y
  1402. depends on X86_64 && HIBERNATION
  1403. source "kernel/power/Kconfig"
  1404. source "drivers/acpi/Kconfig"
  1405. source "drivers/sfi/Kconfig"
  1406. config X86_APM_BOOT
  1407. def_bool y
  1408. depends on APM || APM_MODULE
  1409. menuconfig APM
  1410. tristate "APM (Advanced Power Management) BIOS support"
  1411. depends on X86_32 && PM_SLEEP
  1412. ---help---
  1413. APM is a BIOS specification for saving power using several different
  1414. techniques. This is mostly useful for battery powered laptops with
  1415. APM compliant BIOSes. If you say Y here, the system time will be
  1416. reset after a RESUME operation, the /proc/apm device will provide
  1417. battery status information, and user-space programs will receive
  1418. notification of APM "events" (e.g. battery status change).
  1419. If you select "Y" here, you can disable actual use of the APM
  1420. BIOS by passing the "apm=off" option to the kernel at boot time.
  1421. Note that the APM support is almost completely disabled for
  1422. machines with more than one CPU.
  1423. In order to use APM, you will need supporting software. For location
  1424. and more information, read <file:Documentation/power/pm.txt> and the
  1425. Battery Powered Linux mini-HOWTO, available from
  1426. <http://www.tldp.org/docs.html#howto>.
  1427. This driver does not spin down disk drives (see the hdparm(8)
  1428. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1429. VESA-compliant "green" monitors.
  1430. This driver does not support the TI 4000M TravelMate and the ACER
  1431. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1432. desktop machines also don't have compliant BIOSes, and this driver
  1433. may cause those machines to panic during the boot phase.
  1434. Generally, if you don't have a battery in your machine, there isn't
  1435. much point in using this driver and you should say N. If you get
  1436. random kernel OOPSes or reboots that don't seem to be related to
  1437. anything, try disabling/enabling this option (or disabling/enabling
  1438. APM in your BIOS).
  1439. Some other things you should try when experiencing seemingly random,
  1440. "weird" problems:
  1441. 1) make sure that you have enough swap space and that it is
  1442. enabled.
  1443. 2) pass the "no-hlt" option to the kernel
  1444. 3) switch on floating point emulation in the kernel and pass
  1445. the "no387" option to the kernel
  1446. 4) pass the "floppy=nodma" option to the kernel
  1447. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1448. all but the first 4 MB of RAM)
  1449. 6) make sure that the CPU is not over clocked.
  1450. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1451. 8) disable the cache from your BIOS settings
  1452. 9) install a fan for the video card or exchange video RAM
  1453. 10) install a better fan for the CPU
  1454. 11) exchange RAM chips
  1455. 12) exchange the motherboard.
  1456. To compile this driver as a module, choose M here: the
  1457. module will be called apm.
  1458. if APM
  1459. config APM_IGNORE_USER_SUSPEND
  1460. bool "Ignore USER SUSPEND"
  1461. ---help---
  1462. This option will ignore USER SUSPEND requests. On machines with a
  1463. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1464. series notebooks, it is necessary to say Y because of a BIOS bug.
  1465. config APM_DO_ENABLE
  1466. bool "Enable PM at boot time"
  1467. ---help---
  1468. Enable APM features at boot time. From page 36 of the APM BIOS
  1469. specification: "When disabled, the APM BIOS does not automatically
  1470. power manage devices, enter the Standby State, enter the Suspend
  1471. State, or take power saving steps in response to CPU Idle calls."
  1472. This driver will make CPU Idle calls when Linux is idle (unless this
  1473. feature is turned off -- see "Do CPU IDLE calls", below). This
  1474. should always save battery power, but more complicated APM features
  1475. will be dependent on your BIOS implementation. You may need to turn
  1476. this option off if your computer hangs at boot time when using APM
  1477. support, or if it beeps continuously instead of suspending. Turn
  1478. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1479. T400CDT. This is off by default since most machines do fine without
  1480. this feature.
  1481. config APM_CPU_IDLE
  1482. bool "Make CPU Idle calls when idle"
  1483. ---help---
  1484. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1485. On some machines, this can activate improved power savings, such as
  1486. a slowed CPU clock rate, when the machine is idle. These idle calls
  1487. are made after the idle loop has run for some length of time (e.g.,
  1488. 333 mS). On some machines, this will cause a hang at boot time or
  1489. whenever the CPU becomes idle. (On machines with more than one CPU,
  1490. this option does nothing.)
  1491. config APM_DISPLAY_BLANK
  1492. bool "Enable console blanking using APM"
  1493. ---help---
  1494. Enable console blanking using the APM. Some laptops can use this to
  1495. turn off the LCD backlight when the screen blanker of the Linux
  1496. virtual console blanks the screen. Note that this is only used by
  1497. the virtual console screen blanker, and won't turn off the backlight
  1498. when using the X Window system. This also doesn't have anything to
  1499. do with your VESA-compliant power-saving monitor. Further, this
  1500. option doesn't work for all laptops -- it might not turn off your
  1501. backlight at all, or it might print a lot of errors to the console,
  1502. especially if you are using gpm.
  1503. config APM_ALLOW_INTS
  1504. bool "Allow interrupts during APM BIOS calls"
  1505. ---help---
  1506. Normally we disable external interrupts while we are making calls to
  1507. the APM BIOS as a measure to lessen the effects of a badly behaving
  1508. BIOS implementation. The BIOS should reenable interrupts if it
  1509. needs to. Unfortunately, some BIOSes do not -- especially those in
  1510. many of the newer IBM Thinkpads. If you experience hangs when you
  1511. suspend, try setting this to Y. Otherwise, say N.
  1512. endif # APM
  1513. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1514. source "drivers/cpuidle/Kconfig"
  1515. source "drivers/idle/Kconfig"
  1516. endmenu
  1517. menu "Bus options (PCI etc.)"
  1518. config PCI
  1519. bool "PCI support"
  1520. default y
  1521. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1522. ---help---
  1523. Find out whether you have a PCI motherboard. PCI is the name of a
  1524. bus system, i.e. the way the CPU talks to the other stuff inside
  1525. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1526. VESA. If you have PCI, say Y, otherwise N.
  1527. choice
  1528. prompt "PCI access mode"
  1529. depends on X86_32 && PCI
  1530. default PCI_GOANY
  1531. ---help---
  1532. On PCI systems, the BIOS can be used to detect the PCI devices and
  1533. determine their configuration. However, some old PCI motherboards
  1534. have BIOS bugs and may crash if this is done. Also, some embedded
  1535. PCI-based systems don't have any BIOS at all. Linux can also try to
  1536. detect the PCI hardware directly without using the BIOS.
  1537. With this option, you can specify how Linux should detect the
  1538. PCI devices. If you choose "BIOS", the BIOS will be used,
  1539. if you choose "Direct", the BIOS won't be used, and if you
  1540. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1541. If you choose "Any", the kernel will try MMCONFIG, then the
  1542. direct access method and falls back to the BIOS if that doesn't
  1543. work. If unsure, go with the default, which is "Any".
  1544. config PCI_GOBIOS
  1545. bool "BIOS"
  1546. config PCI_GOMMCONFIG
  1547. bool "MMConfig"
  1548. config PCI_GODIRECT
  1549. bool "Direct"
  1550. config PCI_GOOLPC
  1551. bool "OLPC"
  1552. depends on OLPC
  1553. config PCI_GOANY
  1554. bool "Any"
  1555. endchoice
  1556. config PCI_BIOS
  1557. def_bool y
  1558. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1559. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1560. config PCI_DIRECT
  1561. def_bool y
  1562. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1563. config PCI_MMCONFIG
  1564. def_bool y
  1565. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1566. config PCI_OLPC
  1567. def_bool y
  1568. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1569. config PCI_DOMAINS
  1570. def_bool y
  1571. depends on PCI
  1572. config PCI_MMCONFIG
  1573. bool "Support mmconfig PCI config space access"
  1574. depends on X86_64 && PCI && ACPI
  1575. config PCI_CNB20LE_QUIRK
  1576. bool "Read CNB20LE Host Bridge Windows"
  1577. depends on PCI
  1578. help
  1579. Read the PCI windows out of the CNB20LE host bridge. This allows
  1580. PCI hotplug to work on systems with the CNB20LE chipset which do
  1581. not have ACPI.
  1582. config DMAR
  1583. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1584. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1585. help
  1586. DMA remapping (DMAR) devices support enables independent address
  1587. translations for Direct Memory Access (DMA) from devices.
  1588. These DMA remapping devices are reported via ACPI tables
  1589. and include PCI device scope covered by these DMA
  1590. remapping devices.
  1591. config DMAR_DEFAULT_ON
  1592. def_bool y
  1593. prompt "Enable DMA Remapping Devices by default"
  1594. depends on DMAR
  1595. help
  1596. Selecting this option will enable a DMAR device at boot time if
  1597. one is found. If this option is not selected, DMAR support can
  1598. be enabled by passing intel_iommu=on to the kernel. It is
  1599. recommended you say N here while the DMAR code remains
  1600. experimental.
  1601. config DMAR_BROKEN_GFX_WA
  1602. bool "Workaround broken graphics drivers (going away soon)"
  1603. depends on DMAR && BROKEN
  1604. ---help---
  1605. Current Graphics drivers tend to use physical address
  1606. for DMA and avoid using DMA APIs. Setting this config
  1607. option permits the IOMMU driver to set a unity map for
  1608. all the OS-visible memory. Hence the driver can continue
  1609. to use physical addresses for DMA, at least until this
  1610. option is removed in the 2.6.32 kernel.
  1611. config DMAR_FLOPPY_WA
  1612. def_bool y
  1613. depends on DMAR
  1614. ---help---
  1615. Floppy disk drivers are known to bypass DMA API calls
  1616. thereby failing to work when IOMMU is enabled. This
  1617. workaround will setup a 1:1 mapping for the first
  1618. 16MiB to make floppy (an ISA device) work.
  1619. config INTR_REMAP
  1620. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1621. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1622. ---help---
  1623. Supports Interrupt remapping for IO-APIC and MSI devices.
  1624. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1625. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1626. source "drivers/pci/pcie/Kconfig"
  1627. source "drivers/pci/Kconfig"
  1628. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1629. config ISA_DMA_API
  1630. def_bool y
  1631. if X86_32
  1632. config ISA
  1633. bool "ISA support"
  1634. ---help---
  1635. Find out whether you have ISA slots on your motherboard. ISA is the
  1636. name of a bus system, i.e. the way the CPU talks to the other stuff
  1637. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1638. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1639. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1640. config EISA
  1641. bool "EISA support"
  1642. depends on ISA
  1643. ---help---
  1644. The Extended Industry Standard Architecture (EISA) bus was
  1645. developed as an open alternative to the IBM MicroChannel bus.
  1646. The EISA bus provided some of the features of the IBM MicroChannel
  1647. bus while maintaining backward compatibility with cards made for
  1648. the older ISA bus. The EISA bus saw limited use between 1988 and
  1649. 1995 when it was made obsolete by the PCI bus.
  1650. Say Y here if you are building a kernel for an EISA-based machine.
  1651. Otherwise, say N.
  1652. source "drivers/eisa/Kconfig"
  1653. config MCA
  1654. bool "MCA support"
  1655. ---help---
  1656. MicroChannel Architecture is found in some IBM PS/2 machines and
  1657. laptops. It is a bus system similar to PCI or ISA. See
  1658. <file:Documentation/mca.txt> (and especially the web page given
  1659. there) before attempting to build an MCA bus kernel.
  1660. source "drivers/mca/Kconfig"
  1661. config SCx200
  1662. tristate "NatSemi SCx200 support"
  1663. ---help---
  1664. This provides basic support for National Semiconductor's
  1665. (now AMD's) Geode processors. The driver probes for the
  1666. PCI-IDs of several on-chip devices, so its a good dependency
  1667. for other scx200_* drivers.
  1668. If compiled as a module, the driver is named scx200.
  1669. config SCx200HR_TIMER
  1670. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1671. depends on SCx200
  1672. default y
  1673. ---help---
  1674. This driver provides a clocksource built upon the on-chip
  1675. 27MHz high-resolution timer. Its also a workaround for
  1676. NSC Geode SC-1100's buggy TSC, which loses time when the
  1677. processor goes idle (as is done by the scheduler). The
  1678. other workaround is idle=poll boot option.
  1679. config OLPC
  1680. bool "One Laptop Per Child support"
  1681. select GPIOLIB
  1682. ---help---
  1683. Add support for detecting the unique features of the OLPC
  1684. XO hardware.
  1685. config OLPC_OPENFIRMWARE
  1686. bool "Support for OLPC's Open Firmware"
  1687. depends on !X86_64 && !X86_PAE
  1688. default y if OLPC
  1689. help
  1690. This option adds support for the implementation of Open Firmware
  1691. that is used on the OLPC XO-1 Children's Machine.
  1692. If unsure, say N here.
  1693. endif # X86_32
  1694. config K8_NB
  1695. def_bool y
  1696. depends on CPU_SUP_AMD && PCI
  1697. source "drivers/pcmcia/Kconfig"
  1698. source "drivers/pci/hotplug/Kconfig"
  1699. endmenu
  1700. menu "Executable file formats / Emulations"
  1701. source "fs/Kconfig.binfmt"
  1702. config IA32_EMULATION
  1703. bool "IA32 Emulation"
  1704. depends on X86_64
  1705. select COMPAT_BINFMT_ELF
  1706. ---help---
  1707. Include code to run 32-bit programs under a 64-bit kernel. You should
  1708. likely turn this on, unless you're 100% sure that you don't have any
  1709. 32-bit programs left.
  1710. config IA32_AOUT
  1711. tristate "IA32 a.out support"
  1712. depends on IA32_EMULATION
  1713. ---help---
  1714. Support old a.out binaries in the 32bit emulation.
  1715. config COMPAT
  1716. def_bool y
  1717. depends on IA32_EMULATION
  1718. config COMPAT_FOR_U64_ALIGNMENT
  1719. def_bool COMPAT
  1720. depends on X86_64
  1721. config SYSVIPC_COMPAT
  1722. def_bool y
  1723. depends on COMPAT && SYSVIPC
  1724. endmenu
  1725. config HAVE_ATOMIC_IOMAP
  1726. def_bool y
  1727. depends on X86_32
  1728. source "net/Kconfig"
  1729. source "drivers/Kconfig"
  1730. source "drivers/firmware/Kconfig"
  1731. source "fs/Kconfig"
  1732. source "arch/x86/Kconfig.debug"
  1733. source "security/Kconfig"
  1734. source "crypto/Kconfig"
  1735. source "arch/x86/kvm/Kconfig"
  1736. source "lib/Kconfig"