Kconfig 69 KB

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  1. # Select 32 or 64 bit
  2. config 64BIT
  3. bool "64-bit kernel" if ARCH = "x86"
  4. default ARCH = "x86_64"
  5. ---help---
  6. Say yes to build a 64-bit kernel - formerly known as x86_64
  7. Say no to build a 32-bit kernel - formerly known as i386
  8. config X86_32
  9. def_bool !64BIT
  10. select CLKSRC_I8253
  11. config X86_64
  12. def_bool 64BIT
  13. ### Arch settings
  14. config X86
  15. def_bool y
  16. select HAVE_AOUT if X86_32
  17. select HAVE_UNSTABLE_SCHED_CLOCK
  18. select HAVE_IDE
  19. select HAVE_OPROFILE
  20. select HAVE_PERF_EVENTS
  21. select HAVE_IRQ_WORK
  22. select HAVE_IOREMAP_PROT
  23. select HAVE_KPROBES
  24. select HAVE_MEMBLOCK
  25. select ARCH_WANT_OPTIONAL_GPIOLIB
  26. select ARCH_WANT_FRAME_POINTERS
  27. select HAVE_DMA_ATTRS
  28. select HAVE_KRETPROBES
  29. select HAVE_OPTPROBES
  30. select HAVE_FTRACE_MCOUNT_RECORD
  31. select HAVE_C_RECORDMCOUNT
  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_XZ
  51. select HAVE_KERNEL_LZO
  52. select HAVE_HW_BREAKPOINT
  53. select HAVE_MIXED_BREAKPOINTS_REGS
  54. select PERF_EVENTS
  55. select HAVE_PERF_EVENTS_NMI
  56. select ANON_INODES
  57. select HAVE_ARCH_KMEMCHECK
  58. select HAVE_USER_RETURN_NOTIFIER
  59. select HAVE_ARCH_JUMP_LABEL
  60. select HAVE_TEXT_POKE_SMP
  61. select HAVE_GENERIC_HARDIRQS
  62. select HAVE_SPARSE_IRQ
  63. select GENERIC_FIND_FIRST_BIT
  64. select GENERIC_FIND_NEXT_BIT
  65. select GENERIC_IRQ_PROBE
  66. select GENERIC_PENDING_IRQ if SMP
  67. select GENERIC_IRQ_SHOW
  68. select IRQ_FORCED_THREADING
  69. select USE_GENERIC_SMP_HELPERS if SMP
  70. select HAVE_BPF_JIT if (X86_64 && NET)
  71. config INSTRUCTION_DECODER
  72. def_bool (KPROBES || PERF_EVENTS)
  73. config OUTPUT_FORMAT
  74. string
  75. default "elf32-i386" if X86_32
  76. default "elf64-x86-64" if X86_64
  77. config ARCH_DEFCONFIG
  78. string
  79. default "arch/x86/configs/i386_defconfig" if X86_32
  80. default "arch/x86/configs/x86_64_defconfig" if X86_64
  81. config GENERIC_CMOS_UPDATE
  82. def_bool y
  83. config CLOCKSOURCE_WATCHDOG
  84. def_bool y
  85. config GENERIC_CLOCKEVENTS
  86. def_bool y
  87. config GENERIC_CLOCKEVENTS_BROADCAST
  88. def_bool y
  89. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  90. config LOCKDEP_SUPPORT
  91. def_bool y
  92. config STACKTRACE_SUPPORT
  93. def_bool y
  94. config HAVE_LATENCYTOP_SUPPORT
  95. def_bool y
  96. config MMU
  97. def_bool y
  98. config ZONE_DMA
  99. bool "DMA memory allocation support" if EXPERT
  100. default y
  101. help
  102. DMA memory allocation support allows devices with less than 32-bit
  103. addressing to allocate within the first 16MB of address space.
  104. Disable if no such devices will be used.
  105. If unsure, say Y.
  106. config SBUS
  107. bool
  108. config NEED_DMA_MAP_STATE
  109. def_bool (X86_64 || DMAR || DMA_API_DEBUG)
  110. config NEED_SG_DMA_LENGTH
  111. def_bool y
  112. config GENERIC_ISA_DMA
  113. def_bool ISA_DMA_API
  114. config GENERIC_IOMAP
  115. def_bool y
  116. config GENERIC_BUG
  117. def_bool y
  118. depends on BUG
  119. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  120. config GENERIC_BUG_RELATIVE_POINTERS
  121. bool
  122. config GENERIC_HWEIGHT
  123. def_bool y
  124. config GENERIC_GPIO
  125. bool
  126. config ARCH_MAY_HAVE_PC_FDC
  127. def_bool ISA_DMA_API
  128. config RWSEM_GENERIC_SPINLOCK
  129. def_bool !X86_XADD
  130. config RWSEM_XCHGADD_ALGORITHM
  131. def_bool X86_XADD
  132. config ARCH_HAS_CPU_IDLE_WAIT
  133. def_bool y
  134. config GENERIC_CALIBRATE_DELAY
  135. def_bool y
  136. config GENERIC_TIME_VSYSCALL
  137. bool
  138. default X86_64
  139. config ARCH_HAS_CPU_RELAX
  140. def_bool y
  141. config ARCH_HAS_DEFAULT_IDLE
  142. def_bool y
  143. config ARCH_HAS_CACHE_LINE_SIZE
  144. def_bool y
  145. config HAVE_SETUP_PER_CPU_AREA
  146. def_bool y
  147. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  148. def_bool y
  149. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  150. def_bool y
  151. config HAVE_CPUMASK_OF_CPU_MAP
  152. def_bool X86_64_SMP
  153. config ARCH_HIBERNATION_POSSIBLE
  154. def_bool y
  155. config ARCH_SUSPEND_POSSIBLE
  156. def_bool y
  157. config ZONE_DMA32
  158. bool
  159. default X86_64
  160. config ARCH_POPULATES_NODE_MAP
  161. def_bool y
  162. config AUDIT_ARCH
  163. bool
  164. default X86_64
  165. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  166. def_bool y
  167. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  168. def_bool y
  169. config HAVE_INTEL_TXT
  170. def_bool y
  171. depends on EXPERIMENTAL && DMAR && ACPI
  172. config X86_32_SMP
  173. def_bool y
  174. depends on X86_32 && SMP
  175. config X86_64_SMP
  176. def_bool y
  177. depends on X86_64 && SMP
  178. config X86_HT
  179. def_bool y
  180. depends on SMP
  181. config X86_32_LAZY_GS
  182. def_bool y
  183. depends on X86_32 && !CC_STACKPROTECTOR
  184. config ARCH_HWEIGHT_CFLAGS
  185. string
  186. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  187. 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
  188. config KTIME_SCALAR
  189. def_bool X86_32
  190. config ARCH_CPU_PROBE_RELEASE
  191. def_bool y
  192. depends on HOTPLUG_CPU
  193. source "init/Kconfig"
  194. source "kernel/Kconfig.freezer"
  195. menu "Processor type and features"
  196. source "kernel/time/Kconfig"
  197. config SMP
  198. bool "Symmetric multi-processing support"
  199. ---help---
  200. This enables support for systems with more than one CPU. If you have
  201. a system with only one CPU, like most personal computers, say N. If
  202. you have a system with more than one CPU, say Y.
  203. If you say N here, the kernel will run on single and multiprocessor
  204. machines, but will use only one CPU of a multiprocessor machine. If
  205. you say Y here, the kernel will run on many, but not all,
  206. singleprocessor machines. On a singleprocessor machine, the kernel
  207. will run faster if you say N here.
  208. Note that if you say Y here and choose architecture "586" or
  209. "Pentium" under "Processor family", the kernel will not work on 486
  210. architectures. Similarly, multiprocessor kernels for the "PPro"
  211. architecture may not work on all Pentium based boards.
  212. People using multiprocessor machines who say Y here should also say
  213. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  214. Management" code will be disabled if you say Y here.
  215. See also <file:Documentation/i386/IO-APIC.txt>,
  216. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  217. <http://www.tldp.org/docs.html#howto>.
  218. If you don't know what to do here, say N.
  219. config X86_X2APIC
  220. bool "Support x2apic"
  221. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  222. ---help---
  223. This enables x2apic support on CPUs that have this feature.
  224. This allows 32-bit apic IDs (so it can support very large systems),
  225. and accesses the local apic via MSRs not via mmio.
  226. If you don't know what to do here, say N.
  227. config X86_MPPARSE
  228. bool "Enable MPS table" if ACPI
  229. default y
  230. depends on X86_LOCAL_APIC
  231. ---help---
  232. For old smp systems that do not have proper acpi support. Newer systems
  233. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  234. config X86_BIGSMP
  235. bool "Support for big SMP systems with more than 8 CPUs"
  236. depends on X86_32 && SMP
  237. ---help---
  238. This option is needed for the systems that have more than 8 CPUs
  239. if X86_32
  240. config X86_EXTENDED_PLATFORM
  241. bool "Support for extended (non-PC) x86 platforms"
  242. default y
  243. ---help---
  244. If you disable this option then the kernel will only support
  245. standard PC platforms. (which covers the vast majority of
  246. systems out there.)
  247. If you enable this option then you'll be able to select support
  248. for the following (non-PC) 32 bit x86 platforms:
  249. AMD Elan
  250. NUMAQ (IBM/Sequent)
  251. RDC R-321x SoC
  252. SGI 320/540 (Visual Workstation)
  253. Summit/EXA (IBM x440)
  254. Unisys ES7000 IA32 series
  255. Moorestown MID devices
  256. If you have one of these systems, or if you want to build a
  257. generic distribution kernel, say Y here - otherwise say N.
  258. endif
  259. if X86_64
  260. config X86_EXTENDED_PLATFORM
  261. bool "Support for extended (non-PC) x86 platforms"
  262. default y
  263. ---help---
  264. If you disable this option then the kernel will only support
  265. standard PC platforms. (which covers the vast majority of
  266. systems out there.)
  267. If you enable this option then you'll be able to select support
  268. for the following (non-PC) 64 bit x86 platforms:
  269. ScaleMP vSMP
  270. SGI Ultraviolet
  271. If you have one of these systems, or if you want to build a
  272. generic distribution kernel, say Y here - otherwise say N.
  273. endif
  274. # This is an alphabetically sorted list of 64 bit extended platforms
  275. # Please maintain the alphabetic order if and when there are additions
  276. config X86_VSMP
  277. bool "ScaleMP vSMP"
  278. select PARAVIRT_GUEST
  279. select PARAVIRT
  280. depends on X86_64 && PCI
  281. depends on X86_EXTENDED_PLATFORM
  282. ---help---
  283. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  284. supposed to run on these EM64T-based machines. Only choose this option
  285. if you have one of these machines.
  286. config X86_UV
  287. bool "SGI Ultraviolet"
  288. depends on X86_64
  289. depends on X86_EXTENDED_PLATFORM
  290. depends on NUMA
  291. depends on X86_X2APIC
  292. ---help---
  293. This option is needed in order to support SGI Ultraviolet systems.
  294. If you don't have one of these, you should say N here.
  295. # Following is an alphabetically sorted list of 32 bit extended platforms
  296. # Please maintain the alphabetic order if and when there are additions
  297. config X86_INTEL_CE
  298. bool "CE4100 TV platform"
  299. depends on PCI
  300. depends on PCI_GODIRECT
  301. depends on X86_32
  302. depends on X86_EXTENDED_PLATFORM
  303. select X86_REBOOTFIXUPS
  304. select OF
  305. select OF_EARLY_FLATTREE
  306. ---help---
  307. Select for the Intel CE media processor (CE4100) SOC.
  308. This option compiles in support for the CE4100 SOC for settop
  309. boxes and media devices.
  310. config X86_MRST
  311. bool "Moorestown MID platform"
  312. depends on PCI
  313. depends on PCI_GOANY
  314. depends on X86_32
  315. depends on X86_EXTENDED_PLATFORM
  316. depends on X86_IO_APIC
  317. select APB_TIMER
  318. select I2C
  319. select SPI
  320. select INTEL_SCU_IPC
  321. select X86_PLATFORM_DEVICES
  322. ---help---
  323. Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
  324. Internet Device(MID) platform. Moorestown consists of two chips:
  325. Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
  326. Unlike standard x86 PCs, Moorestown does not have many legacy devices
  327. nor standard legacy replacement devices/features. e.g. Moorestown does
  328. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  329. config X86_RDC321X
  330. bool "RDC R-321x SoC"
  331. depends on X86_32
  332. depends on X86_EXTENDED_PLATFORM
  333. select M486
  334. select X86_REBOOTFIXUPS
  335. ---help---
  336. This option is needed for RDC R-321x system-on-chip, also known
  337. as R-8610-(G).
  338. If you don't have one of these chips, you should say N here.
  339. config X86_32_NON_STANDARD
  340. bool "Support non-standard 32-bit SMP architectures"
  341. depends on X86_32 && SMP
  342. depends on X86_EXTENDED_PLATFORM
  343. ---help---
  344. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  345. subarchitectures. It is intended for a generic binary kernel.
  346. if you select them all, kernel will probe it one by one. and will
  347. fallback to default.
  348. # Alphabetically sorted list of Non standard 32 bit platforms
  349. config X86_NUMAQ
  350. bool "NUMAQ (IBM/Sequent)"
  351. depends on X86_32_NON_STANDARD
  352. depends on PCI
  353. select NUMA
  354. select X86_MPPARSE
  355. ---help---
  356. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  357. NUMA multiquad box. This changes the way that processors are
  358. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  359. of Flat Logical. You will need a new lynxer.elf file to flash your
  360. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  361. config X86_SUPPORTS_MEMORY_FAILURE
  362. def_bool y
  363. # MCE code calls memory_failure():
  364. depends on X86_MCE
  365. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  366. depends on !X86_NUMAQ
  367. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  368. depends on X86_64 || !SPARSEMEM
  369. select ARCH_SUPPORTS_MEMORY_FAILURE
  370. config X86_VISWS
  371. bool "SGI 320/540 (Visual Workstation)"
  372. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  373. depends on X86_32_NON_STANDARD
  374. ---help---
  375. The SGI Visual Workstation series is an IA32-based workstation
  376. based on SGI systems chips with some legacy PC hardware attached.
  377. Say Y here to create a kernel to run on the SGI 320 or 540.
  378. A kernel compiled for the Visual Workstation will run on general
  379. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  380. config X86_SUMMIT
  381. bool "Summit/EXA (IBM x440)"
  382. depends on X86_32_NON_STANDARD
  383. ---help---
  384. This option is needed for IBM systems that use the Summit/EXA chipset.
  385. In particular, it is needed for the x440.
  386. config X86_ES7000
  387. bool "Unisys ES7000 IA32 series"
  388. depends on X86_32_NON_STANDARD && X86_BIGSMP
  389. ---help---
  390. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  391. supposed to run on an IA32-based Unisys ES7000 system.
  392. config X86_32_IRIS
  393. tristate "Eurobraille/Iris poweroff module"
  394. depends on X86_32
  395. ---help---
  396. The Iris machines from EuroBraille do not have APM or ACPI support
  397. to shut themselves down properly. A special I/O sequence is
  398. needed to do so, which is what this module does at
  399. kernel shutdown.
  400. This is only for Iris machines from EuroBraille.
  401. If unused, say N.
  402. config SCHED_OMIT_FRAME_POINTER
  403. def_bool y
  404. prompt "Single-depth WCHAN output"
  405. depends on X86
  406. ---help---
  407. Calculate simpler /proc/<PID>/wchan values. If this option
  408. is disabled then wchan values will recurse back to the
  409. caller function. This provides more accurate wchan values,
  410. at the expense of slightly more scheduling overhead.
  411. If in doubt, say "Y".
  412. menuconfig PARAVIRT_GUEST
  413. bool "Paravirtualized guest support"
  414. ---help---
  415. Say Y here to get to see options related to running Linux under
  416. various hypervisors. This option alone does not add any kernel code.
  417. If you say N, all options in this submenu will be skipped and disabled.
  418. if PARAVIRT_GUEST
  419. source "arch/x86/xen/Kconfig"
  420. config KVM_CLOCK
  421. bool "KVM paravirtualized clock"
  422. select PARAVIRT
  423. select PARAVIRT_CLOCK
  424. ---help---
  425. Turning on this option will allow you to run a paravirtualized clock
  426. when running over the KVM hypervisor. Instead of relying on a PIT
  427. (or probably other) emulation by the underlying device model, the host
  428. provides the guest with timing infrastructure such as time of day, and
  429. system time
  430. config KVM_GUEST
  431. bool "KVM Guest support"
  432. select PARAVIRT
  433. ---help---
  434. This option enables various optimizations for running under the KVM
  435. hypervisor.
  436. source "arch/x86/lguest/Kconfig"
  437. config PARAVIRT
  438. bool "Enable paravirtualization code"
  439. ---help---
  440. This changes the kernel so it can modify itself when it is run
  441. under a hypervisor, potentially improving performance significantly
  442. over full virtualization. However, when run without a hypervisor
  443. the kernel is theoretically slower and slightly larger.
  444. config PARAVIRT_SPINLOCKS
  445. bool "Paravirtualization layer for spinlocks"
  446. depends on PARAVIRT && SMP && EXPERIMENTAL
  447. ---help---
  448. Paravirtualized spinlocks allow a pvops backend to replace the
  449. spinlock implementation with something virtualization-friendly
  450. (for example, block the virtual CPU rather than spinning).
  451. Unfortunately the downside is an up to 5% performance hit on
  452. native kernels, with various workloads.
  453. If you are unsure how to answer this question, answer N.
  454. config PARAVIRT_CLOCK
  455. bool
  456. endif
  457. config PARAVIRT_DEBUG
  458. bool "paravirt-ops debugging"
  459. depends on PARAVIRT && DEBUG_KERNEL
  460. ---help---
  461. Enable to debug paravirt_ops internals. Specifically, BUG if
  462. a paravirt_op is missing when it is called.
  463. config NO_BOOTMEM
  464. def_bool y
  465. config MEMTEST
  466. bool "Memtest"
  467. ---help---
  468. This option adds a kernel parameter 'memtest', which allows memtest
  469. to be set.
  470. memtest=0, mean disabled; -- default
  471. memtest=1, mean do 1 test pattern;
  472. ...
  473. memtest=4, mean do 4 test patterns.
  474. If you are unsure how to answer this question, answer N.
  475. config X86_SUMMIT_NUMA
  476. def_bool y
  477. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  478. config X86_CYCLONE_TIMER
  479. def_bool y
  480. depends on X86_32_NON_STANDARD
  481. source "arch/x86/Kconfig.cpu"
  482. config HPET_TIMER
  483. def_bool X86_64
  484. prompt "HPET Timer Support" if X86_32
  485. ---help---
  486. Use the IA-PC HPET (High Precision Event Timer) to manage
  487. time in preference to the PIT and RTC, if a HPET is
  488. present.
  489. HPET is the next generation timer replacing legacy 8254s.
  490. The HPET provides a stable time base on SMP
  491. systems, unlike the TSC, but it is more expensive to access,
  492. as it is off-chip. You can find the HPET spec at
  493. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  494. You can safely choose Y here. However, HPET will only be
  495. activated if the platform and the BIOS support this feature.
  496. Otherwise the 8254 will be used for timing services.
  497. Choose N to continue using the legacy 8254 timer.
  498. config HPET_EMULATE_RTC
  499. def_bool y
  500. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  501. config APB_TIMER
  502. def_bool y if MRST
  503. prompt "Langwell APB Timer Support" if X86_MRST
  504. help
  505. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  506. The APBT provides a stable time base on SMP
  507. systems, unlike the TSC, but it is more expensive to access,
  508. as it is off-chip. APB timers are always running regardless of CPU
  509. C states, they are used as per CPU clockevent device when possible.
  510. # Mark as expert because too many people got it wrong.
  511. # The code disables itself when not needed.
  512. config DMI
  513. default y
  514. bool "Enable DMI scanning" if EXPERT
  515. ---help---
  516. Enabled scanning of DMI to identify machine quirks. Say Y
  517. here unless you have verified that your setup is not
  518. affected by entries in the DMI blacklist. Required by PNP
  519. BIOS code.
  520. config GART_IOMMU
  521. bool "GART IOMMU support" if EXPERT
  522. default y
  523. select SWIOTLB
  524. depends on X86_64 && PCI && AMD_NB
  525. ---help---
  526. Support for full DMA access of devices with 32bit memory access only
  527. on systems with more than 3GB. This is usually needed for USB,
  528. sound, many IDE/SATA chipsets and some other devices.
  529. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  530. based hardware IOMMU and a software bounce buffer based IOMMU used
  531. on Intel systems and as fallback.
  532. The code is only active when needed (enough memory and limited
  533. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  534. too.
  535. config CALGARY_IOMMU
  536. bool "IBM Calgary IOMMU support"
  537. select SWIOTLB
  538. depends on X86_64 && PCI && EXPERIMENTAL
  539. ---help---
  540. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  541. systems. Needed to run systems with more than 3GB of memory
  542. properly with 32-bit PCI devices that do not support DAC
  543. (Double Address Cycle). Calgary also supports bus level
  544. isolation, where all DMAs pass through the IOMMU. This
  545. prevents them from going anywhere except their intended
  546. destination. This catches hard-to-find kernel bugs and
  547. mis-behaving drivers and devices that do not use the DMA-API
  548. properly to set up their DMA buffers. The IOMMU can be
  549. turned off at boot time with the iommu=off parameter.
  550. Normally the kernel will make the right choice by itself.
  551. If unsure, say Y.
  552. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  553. def_bool y
  554. prompt "Should Calgary be enabled by default?"
  555. depends on CALGARY_IOMMU
  556. ---help---
  557. Should Calgary be enabled by default? if you choose 'y', Calgary
  558. will be used (if it exists). If you choose 'n', Calgary will not be
  559. used even if it exists. If you choose 'n' and would like to use
  560. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  561. If unsure, say Y.
  562. config AMD_IOMMU
  563. bool "AMD IOMMU support"
  564. select SWIOTLB
  565. select PCI_MSI
  566. select PCI_IOV
  567. depends on X86_64 && PCI && ACPI
  568. ---help---
  569. With this option you can enable support for AMD IOMMU hardware in
  570. your system. An IOMMU is a hardware component which provides
  571. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  572. can isolate the the DMA memory of different devices and protect the
  573. system from misbehaving device drivers or hardware.
  574. You can find out if your system has an AMD IOMMU if you look into
  575. your BIOS for an option to enable it or if you have an IVRS ACPI
  576. table.
  577. config AMD_IOMMU_STATS
  578. bool "Export AMD IOMMU statistics to debugfs"
  579. depends on AMD_IOMMU
  580. select DEBUG_FS
  581. ---help---
  582. This option enables code in the AMD IOMMU driver to collect various
  583. statistics about whats happening in the driver and exports that
  584. information to userspace via debugfs.
  585. If unsure, say N.
  586. # need this always selected by IOMMU for the VIA workaround
  587. config SWIOTLB
  588. def_bool y if X86_64
  589. ---help---
  590. Support for software bounce buffers used on x86-64 systems
  591. which don't have a hardware IOMMU (e.g. the current generation
  592. of Intel's x86-64 CPUs). Using this PCI devices which can only
  593. access 32-bits of memory can be used on systems with more than
  594. 3 GB of memory. If unsure, say Y.
  595. config IOMMU_HELPER
  596. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  597. config IOMMU_API
  598. def_bool (AMD_IOMMU || DMAR)
  599. config MAXSMP
  600. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  601. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  602. select CPUMASK_OFFSTACK
  603. ---help---
  604. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  605. If unsure, say N.
  606. config NR_CPUS
  607. int "Maximum number of CPUs" if SMP && !MAXSMP
  608. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  609. range 2 512 if SMP && !MAXSMP
  610. default "1" if !SMP
  611. default "4096" if MAXSMP
  612. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  613. default "8" if SMP
  614. ---help---
  615. This allows you to specify the maximum number of CPUs which this
  616. kernel will support. The maximum supported value is 512 and the
  617. minimum value which makes sense is 2.
  618. This is purely to save memory - each supported CPU adds
  619. approximately eight kilobytes to the kernel image.
  620. config SCHED_SMT
  621. bool "SMT (Hyperthreading) scheduler support"
  622. depends on X86_HT
  623. ---help---
  624. SMT scheduler support improves the CPU scheduler's decision making
  625. when dealing with Intel Pentium 4 chips with HyperThreading at a
  626. cost of slightly increased overhead in some places. If unsure say
  627. N here.
  628. config SCHED_MC
  629. def_bool y
  630. prompt "Multi-core scheduler support"
  631. depends on X86_HT
  632. ---help---
  633. Multi-core scheduler support improves the CPU scheduler's decision
  634. making when dealing with multi-core CPU chips at a cost of slightly
  635. increased overhead in some places. If unsure say N here.
  636. config IRQ_TIME_ACCOUNTING
  637. bool "Fine granularity task level IRQ time accounting"
  638. default n
  639. ---help---
  640. Select this option to enable fine granularity task irq time
  641. accounting. This is done by reading a timestamp on each
  642. transitions between softirq and hardirq state, so there can be a
  643. small performance impact.
  644. If in doubt, say N here.
  645. source "kernel/Kconfig.preempt"
  646. config X86_UP_APIC
  647. bool "Local APIC support on uniprocessors"
  648. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  649. ---help---
  650. A local APIC (Advanced Programmable Interrupt Controller) is an
  651. integrated interrupt controller in the CPU. If you have a single-CPU
  652. system which has a processor with a local APIC, you can say Y here to
  653. enable and use it. If you say Y here even though your machine doesn't
  654. have a local APIC, then the kernel will still run with no slowdown at
  655. all. The local APIC supports CPU-generated self-interrupts (timer,
  656. performance counters), and the NMI watchdog which detects hard
  657. lockups.
  658. config X86_UP_IOAPIC
  659. bool "IO-APIC support on uniprocessors"
  660. depends on X86_UP_APIC
  661. ---help---
  662. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  663. SMP-capable replacement for PC-style interrupt controllers. Most
  664. SMP systems and many recent uniprocessor systems have one.
  665. If you have a single-CPU system with an IO-APIC, you can say Y here
  666. to use it. If you say Y here even though your machine doesn't have
  667. an IO-APIC, then the kernel will still run with no slowdown at all.
  668. config X86_LOCAL_APIC
  669. def_bool y
  670. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  671. config X86_IO_APIC
  672. def_bool y
  673. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
  674. config X86_VISWS_APIC
  675. def_bool y
  676. depends on X86_32 && X86_VISWS
  677. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  678. bool "Reroute for broken boot IRQs"
  679. depends on X86_IO_APIC
  680. ---help---
  681. This option enables a workaround that fixes a source of
  682. spurious interrupts. This is recommended when threaded
  683. interrupt handling is used on systems where the generation of
  684. superfluous "boot interrupts" cannot be disabled.
  685. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  686. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  687. kernel does during interrupt handling). On chipsets where this
  688. boot IRQ generation cannot be disabled, this workaround keeps
  689. the original IRQ line masked so that only the equivalent "boot
  690. IRQ" is delivered to the CPUs. The workaround also tells the
  691. kernel to set up the IRQ handler on the boot IRQ line. In this
  692. way only one interrupt is delivered to the kernel. Otherwise
  693. the spurious second interrupt may cause the kernel to bring
  694. down (vital) interrupt lines.
  695. Only affects "broken" chipsets. Interrupt sharing may be
  696. increased on these systems.
  697. config X86_MCE
  698. bool "Machine Check / overheating reporting"
  699. ---help---
  700. Machine Check support allows the processor to notify the
  701. kernel if it detects a problem (e.g. overheating, data corruption).
  702. The action the kernel takes depends on the severity of the problem,
  703. ranging from warning messages to halting the machine.
  704. config X86_MCE_INTEL
  705. def_bool y
  706. prompt "Intel MCE features"
  707. depends on X86_MCE && X86_LOCAL_APIC
  708. ---help---
  709. Additional support for intel specific MCE features such as
  710. the thermal monitor.
  711. config X86_MCE_AMD
  712. def_bool y
  713. prompt "AMD MCE features"
  714. depends on X86_MCE && X86_LOCAL_APIC
  715. ---help---
  716. Additional support for AMD specific MCE features such as
  717. the DRAM Error Threshold.
  718. config X86_ANCIENT_MCE
  719. bool "Support for old Pentium 5 / WinChip machine checks"
  720. depends on X86_32 && X86_MCE
  721. ---help---
  722. Include support for machine check handling on old Pentium 5 or WinChip
  723. systems. These typically need to be enabled explicitely on the command
  724. line.
  725. config X86_MCE_THRESHOLD
  726. depends on X86_MCE_AMD || X86_MCE_INTEL
  727. def_bool y
  728. config X86_MCE_INJECT
  729. depends on X86_MCE
  730. tristate "Machine check injector support"
  731. ---help---
  732. Provide support for injecting machine checks for testing purposes.
  733. If you don't know what a machine check is and you don't do kernel
  734. QA it is safe to say n.
  735. config X86_THERMAL_VECTOR
  736. def_bool y
  737. depends on X86_MCE_INTEL
  738. config VM86
  739. bool "Enable VM86 support" if EXPERT
  740. default y
  741. depends on X86_32
  742. ---help---
  743. This option is required by programs like DOSEMU to run 16-bit legacy
  744. code on X86 processors. It also may be needed by software like
  745. XFree86 to initialize some video cards via BIOS. Disabling this
  746. option saves about 6k.
  747. config TOSHIBA
  748. tristate "Toshiba Laptop support"
  749. depends on X86_32
  750. ---help---
  751. This adds a driver to safely access the System Management Mode of
  752. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  753. not work on models with a Phoenix BIOS. The System Management Mode
  754. is used to set the BIOS and power saving options on Toshiba portables.
  755. For information on utilities to make use of this driver see the
  756. Toshiba Linux utilities web site at:
  757. <http://www.buzzard.org.uk/toshiba/>.
  758. Say Y if you intend to run this kernel on a Toshiba portable.
  759. Say N otherwise.
  760. config I8K
  761. tristate "Dell laptop support"
  762. select HWMON
  763. ---help---
  764. This adds a driver to safely access the System Management Mode
  765. of the CPU on the Dell Inspiron 8000. The System Management Mode
  766. is used to read cpu temperature and cooling fan status and to
  767. control the fans on the I8K portables.
  768. This driver has been tested only on the Inspiron 8000 but it may
  769. also work with other Dell laptops. You can force loading on other
  770. models by passing the parameter `force=1' to the module. Use at
  771. your own risk.
  772. For information on utilities to make use of this driver see the
  773. I8K Linux utilities web site at:
  774. <http://people.debian.org/~dz/i8k/>
  775. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  776. Say N otherwise.
  777. config X86_REBOOTFIXUPS
  778. bool "Enable X86 board specific fixups for reboot"
  779. depends on X86_32
  780. ---help---
  781. This enables chipset and/or board specific fixups to be done
  782. in order to get reboot to work correctly. This is only needed on
  783. some combinations of hardware and BIOS. The symptom, for which
  784. this config is intended, is when reboot ends with a stalled/hung
  785. system.
  786. Currently, the only fixup is for the Geode machines using
  787. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  788. Say Y if you want to enable the fixup. Currently, it's safe to
  789. enable this option even if you don't need it.
  790. Say N otherwise.
  791. config MICROCODE
  792. tristate "/dev/cpu/microcode - microcode support"
  793. select FW_LOADER
  794. ---help---
  795. If you say Y here, you will be able to update the microcode on
  796. certain Intel and AMD processors. The Intel support is for the
  797. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  798. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  799. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  800. You will obviously need the actual microcode binary data itself
  801. which is not shipped with the Linux kernel.
  802. This option selects the general module only, you need to select
  803. at least one vendor specific module as well.
  804. To compile this driver as a module, choose M here: the
  805. module will be called microcode.
  806. config MICROCODE_INTEL
  807. bool "Intel microcode patch loading support"
  808. depends on MICROCODE
  809. default MICROCODE
  810. select FW_LOADER
  811. ---help---
  812. This options enables microcode patch loading support for Intel
  813. processors.
  814. For latest news and information on obtaining all the required
  815. Intel ingredients for this driver, check:
  816. <http://www.urbanmyth.org/microcode/>.
  817. config MICROCODE_AMD
  818. bool "AMD microcode patch loading support"
  819. depends on MICROCODE
  820. select FW_LOADER
  821. ---help---
  822. If you select this option, microcode patch loading support for AMD
  823. processors will be enabled.
  824. config MICROCODE_OLD_INTERFACE
  825. def_bool y
  826. depends on MICROCODE
  827. config X86_MSR
  828. tristate "/dev/cpu/*/msr - Model-specific register support"
  829. ---help---
  830. This device gives privileged processes access to the x86
  831. Model-Specific Registers (MSRs). It is a character device with
  832. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  833. MSR accesses are directed to a specific CPU on multi-processor
  834. systems.
  835. config X86_CPUID
  836. tristate "/dev/cpu/*/cpuid - CPU information support"
  837. ---help---
  838. This device gives processes access to the x86 CPUID instruction to
  839. be executed on a specific processor. It is a character device
  840. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  841. /dev/cpu/31/cpuid.
  842. choice
  843. prompt "High Memory Support"
  844. default HIGHMEM64G if X86_NUMAQ
  845. default HIGHMEM4G
  846. depends on X86_32
  847. config NOHIGHMEM
  848. bool "off"
  849. depends on !X86_NUMAQ
  850. ---help---
  851. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  852. However, the address space of 32-bit x86 processors is only 4
  853. Gigabytes large. That means that, if you have a large amount of
  854. physical memory, not all of it can be "permanently mapped" by the
  855. kernel. The physical memory that's not permanently mapped is called
  856. "high memory".
  857. If you are compiling a kernel which will never run on a machine with
  858. more than 1 Gigabyte total physical RAM, answer "off" here (default
  859. choice and suitable for most users). This will result in a "3GB/1GB"
  860. split: 3GB are mapped so that each process sees a 3GB virtual memory
  861. space and the remaining part of the 4GB virtual memory space is used
  862. by the kernel to permanently map as much physical memory as
  863. possible.
  864. If the machine has between 1 and 4 Gigabytes physical RAM, then
  865. answer "4GB" here.
  866. If more than 4 Gigabytes is used then answer "64GB" here. This
  867. selection turns Intel PAE (Physical Address Extension) mode on.
  868. PAE implements 3-level paging on IA32 processors. PAE is fully
  869. supported by Linux, PAE mode is implemented on all recent Intel
  870. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  871. then the kernel will not boot on CPUs that don't support PAE!
  872. The actual amount of total physical memory will either be
  873. auto detected or can be forced by using a kernel command line option
  874. such as "mem=256M". (Try "man bootparam" or see the documentation of
  875. your boot loader (lilo or loadlin) about how to pass options to the
  876. kernel at boot time.)
  877. If unsure, say "off".
  878. config HIGHMEM4G
  879. bool "4GB"
  880. depends on !X86_NUMAQ
  881. ---help---
  882. Select this if you have a 32-bit processor and between 1 and 4
  883. gigabytes of physical RAM.
  884. config HIGHMEM64G
  885. bool "64GB"
  886. depends on !M386 && !M486
  887. select X86_PAE
  888. ---help---
  889. Select this if you have a 32-bit processor and more than 4
  890. gigabytes of physical RAM.
  891. endchoice
  892. choice
  893. depends on EXPERIMENTAL
  894. prompt "Memory split" if EXPERT
  895. default VMSPLIT_3G
  896. depends on X86_32
  897. ---help---
  898. Select the desired split between kernel and user memory.
  899. If the address range available to the kernel is less than the
  900. physical memory installed, the remaining memory will be available
  901. as "high memory". Accessing high memory is a little more costly
  902. than low memory, as it needs to be mapped into the kernel first.
  903. Note that increasing the kernel address space limits the range
  904. available to user programs, making the address space there
  905. tighter. Selecting anything other than the default 3G/1G split
  906. will also likely make your kernel incompatible with binary-only
  907. kernel modules.
  908. If you are not absolutely sure what you are doing, leave this
  909. option alone!
  910. config VMSPLIT_3G
  911. bool "3G/1G user/kernel split"
  912. config VMSPLIT_3G_OPT
  913. depends on !X86_PAE
  914. bool "3G/1G user/kernel split (for full 1G low memory)"
  915. config VMSPLIT_2G
  916. bool "2G/2G user/kernel split"
  917. config VMSPLIT_2G_OPT
  918. depends on !X86_PAE
  919. bool "2G/2G user/kernel split (for full 2G low memory)"
  920. config VMSPLIT_1G
  921. bool "1G/3G user/kernel split"
  922. endchoice
  923. config PAGE_OFFSET
  924. hex
  925. default 0xB0000000 if VMSPLIT_3G_OPT
  926. default 0x80000000 if VMSPLIT_2G
  927. default 0x78000000 if VMSPLIT_2G_OPT
  928. default 0x40000000 if VMSPLIT_1G
  929. default 0xC0000000
  930. depends on X86_32
  931. config HIGHMEM
  932. def_bool y
  933. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  934. config X86_PAE
  935. bool "PAE (Physical Address Extension) Support"
  936. depends on X86_32 && !HIGHMEM4G
  937. ---help---
  938. PAE is required for NX support, and furthermore enables
  939. larger swapspace support for non-overcommit purposes. It
  940. has the cost of more pagetable lookup overhead, and also
  941. consumes more pagetable space per process.
  942. config ARCH_PHYS_ADDR_T_64BIT
  943. def_bool X86_64 || X86_PAE
  944. config ARCH_DMA_ADDR_T_64BIT
  945. def_bool X86_64 || HIGHMEM64G
  946. config DIRECT_GBPAGES
  947. bool "Enable 1GB pages for kernel pagetables" if EXPERT
  948. default y
  949. depends on X86_64
  950. ---help---
  951. Allow the kernel linear mapping to use 1GB pages on CPUs that
  952. support it. This can improve the kernel's performance a tiny bit by
  953. reducing TLB pressure. If in doubt, say "Y".
  954. # Common NUMA Features
  955. config NUMA
  956. bool "Numa Memory Allocation and Scheduler Support"
  957. depends on SMP
  958. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  959. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  960. ---help---
  961. Enable NUMA (Non Uniform Memory Access) support.
  962. The kernel will try to allocate memory used by a CPU on the
  963. local memory controller of the CPU and add some more
  964. NUMA awareness to the kernel.
  965. For 64-bit this is recommended if the system is Intel Core i7
  966. (or later), AMD Opteron, or EM64T NUMA.
  967. For 32-bit this is only needed on (rare) 32-bit-only platforms
  968. that support NUMA topologies, such as NUMAQ / Summit, or if you
  969. boot a 32-bit kernel on a 64-bit NUMA platform.
  970. Otherwise, you should say N.
  971. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  972. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  973. config AMD_NUMA
  974. def_bool y
  975. prompt "Old style AMD Opteron NUMA detection"
  976. depends on NUMA && PCI
  977. ---help---
  978. Enable AMD NUMA node topology detection. You should say Y here if
  979. you have a multi processor AMD system. This uses an old method to
  980. read the NUMA configuration directly from the builtin Northbridge
  981. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  982. which also takes priority if both are compiled in.
  983. config X86_64_ACPI_NUMA
  984. def_bool y
  985. prompt "ACPI NUMA detection"
  986. depends on X86_64 && NUMA && ACPI && PCI
  987. select ACPI_NUMA
  988. ---help---
  989. Enable ACPI SRAT based node topology detection.
  990. # Some NUMA nodes have memory ranges that span
  991. # other nodes. Even though a pfn is valid and
  992. # between a node's start and end pfns, it may not
  993. # reside on that node. See memmap_init_zone()
  994. # for details.
  995. config NODES_SPAN_OTHER_NODES
  996. def_bool y
  997. depends on X86_64_ACPI_NUMA
  998. config NUMA_EMU
  999. bool "NUMA emulation"
  1000. depends on NUMA
  1001. ---help---
  1002. Enable NUMA emulation. A flat machine will be split
  1003. into virtual nodes when booted with "numa=fake=N", where N is the
  1004. number of nodes. This is only useful for debugging.
  1005. config NODES_SHIFT
  1006. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1007. range 1 10
  1008. default "10" if MAXSMP
  1009. default "6" if X86_64
  1010. default "4" if X86_NUMAQ
  1011. default "3"
  1012. depends on NEED_MULTIPLE_NODES
  1013. ---help---
  1014. Specify the maximum number of NUMA Nodes available on the target
  1015. system. Increases memory reserved to accommodate various tables.
  1016. config HAVE_ARCH_BOOTMEM
  1017. def_bool y
  1018. depends on X86_32 && NUMA
  1019. config HAVE_ARCH_ALLOC_REMAP
  1020. def_bool y
  1021. depends on X86_32 && NUMA
  1022. config ARCH_HAVE_MEMORY_PRESENT
  1023. def_bool y
  1024. depends on X86_32 && DISCONTIGMEM
  1025. config NEED_NODE_MEMMAP_SIZE
  1026. def_bool y
  1027. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1028. config ARCH_FLATMEM_ENABLE
  1029. def_bool y
  1030. depends on X86_32 && !NUMA
  1031. config ARCH_DISCONTIGMEM_ENABLE
  1032. def_bool y
  1033. depends on NUMA && X86_32
  1034. config ARCH_DISCONTIGMEM_DEFAULT
  1035. def_bool y
  1036. depends on NUMA && X86_32
  1037. config ARCH_SPARSEMEM_ENABLE
  1038. def_bool y
  1039. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1040. select SPARSEMEM_STATIC if X86_32
  1041. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1042. config ARCH_SPARSEMEM_DEFAULT
  1043. def_bool y
  1044. depends on X86_64
  1045. config ARCH_SELECT_MEMORY_MODEL
  1046. def_bool y
  1047. depends on ARCH_SPARSEMEM_ENABLE
  1048. config ARCH_MEMORY_PROBE
  1049. def_bool X86_64
  1050. depends on MEMORY_HOTPLUG
  1051. config ARCH_PROC_KCORE_TEXT
  1052. def_bool y
  1053. depends on X86_64 && PROC_KCORE
  1054. config ILLEGAL_POINTER_VALUE
  1055. hex
  1056. default 0 if X86_32
  1057. default 0xdead000000000000 if X86_64
  1058. source "mm/Kconfig"
  1059. config HIGHPTE
  1060. bool "Allocate 3rd-level pagetables from highmem"
  1061. depends on HIGHMEM
  1062. ---help---
  1063. The VM uses one page table entry for each page of physical memory.
  1064. For systems with a lot of RAM, this can be wasteful of precious
  1065. low memory. Setting this option will put user-space page table
  1066. entries in high memory.
  1067. config X86_CHECK_BIOS_CORRUPTION
  1068. bool "Check for low memory corruption"
  1069. ---help---
  1070. Periodically check for memory corruption in low memory, which
  1071. is suspected to be caused by BIOS. Even when enabled in the
  1072. configuration, it is disabled at runtime. Enable it by
  1073. setting "memory_corruption_check=1" on the kernel command
  1074. line. By default it scans the low 64k of memory every 60
  1075. seconds; see the memory_corruption_check_size and
  1076. memory_corruption_check_period parameters in
  1077. Documentation/kernel-parameters.txt to adjust this.
  1078. When enabled with the default parameters, this option has
  1079. almost no overhead, as it reserves a relatively small amount
  1080. of memory and scans it infrequently. It both detects corruption
  1081. and prevents it from affecting the running system.
  1082. It is, however, intended as a diagnostic tool; if repeatable
  1083. BIOS-originated corruption always affects the same memory,
  1084. you can use memmap= to prevent the kernel from using that
  1085. memory.
  1086. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1087. bool "Set the default setting of memory_corruption_check"
  1088. depends on X86_CHECK_BIOS_CORRUPTION
  1089. default y
  1090. ---help---
  1091. Set whether the default state of memory_corruption_check is
  1092. on or off.
  1093. config X86_RESERVE_LOW
  1094. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1095. default 64
  1096. range 4 640
  1097. ---help---
  1098. Specify the amount of low memory to reserve for the BIOS.
  1099. The first page contains BIOS data structures that the kernel
  1100. must not use, so that page must always be reserved.
  1101. By default we reserve the first 64K of physical RAM, as a
  1102. number of BIOSes are known to corrupt that memory range
  1103. during events such as suspend/resume or monitor cable
  1104. insertion, so it must not be used by the kernel.
  1105. You can set this to 4 if you are absolutely sure that you
  1106. trust the BIOS to get all its memory reservations and usages
  1107. right. If you know your BIOS have problems beyond the
  1108. default 64K area, you can set this to 640 to avoid using the
  1109. entire low memory range.
  1110. If you have doubts about the BIOS (e.g. suspend/resume does
  1111. not work or there's kernel crashes after certain hardware
  1112. hotplug events) then you might want to enable
  1113. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1114. typical corruption patterns.
  1115. Leave this to the default value of 64 if you are unsure.
  1116. config MATH_EMULATION
  1117. bool
  1118. prompt "Math emulation" if X86_32
  1119. ---help---
  1120. Linux can emulate a math coprocessor (used for floating point
  1121. operations) if you don't have one. 486DX and Pentium processors have
  1122. a math coprocessor built in, 486SX and 386 do not, unless you added
  1123. a 487DX or 387, respectively. (The messages during boot time can
  1124. give you some hints here ["man dmesg"].) Everyone needs either a
  1125. coprocessor or this emulation.
  1126. If you don't have a math coprocessor, you need to say Y here; if you
  1127. say Y here even though you have a coprocessor, the coprocessor will
  1128. be used nevertheless. (This behavior can be changed with the kernel
  1129. command line option "no387", which comes handy if your coprocessor
  1130. is broken. Try "man bootparam" or see the documentation of your boot
  1131. loader (lilo or loadlin) about how to pass options to the kernel at
  1132. boot time.) This means that it is a good idea to say Y here if you
  1133. intend to use this kernel on different machines.
  1134. More information about the internals of the Linux math coprocessor
  1135. emulation can be found in <file:arch/x86/math-emu/README>.
  1136. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1137. kernel, it won't hurt.
  1138. config MTRR
  1139. def_bool y
  1140. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1141. ---help---
  1142. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1143. the Memory Type Range Registers (MTRRs) may be used to control
  1144. processor access to memory ranges. This is most useful if you have
  1145. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1146. allows bus write transfers to be combined into a larger transfer
  1147. before bursting over the PCI/AGP bus. This can increase performance
  1148. of image write operations 2.5 times or more. Saying Y here creates a
  1149. /proc/mtrr file which may be used to manipulate your processor's
  1150. MTRRs. Typically the X server should use this.
  1151. This code has a reasonably generic interface so that similar
  1152. control registers on other processors can be easily supported
  1153. as well:
  1154. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1155. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1156. these, the ARRs are used to emulate the MTRRs.
  1157. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1158. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1159. write-combining. All of these processors are supported by this code
  1160. and it makes sense to say Y here if you have one of them.
  1161. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1162. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1163. can lead to all sorts of problems, so it's good to say Y here.
  1164. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1165. just add about 9 KB to your kernel.
  1166. See <file:Documentation/x86/mtrr.txt> for more information.
  1167. config MTRR_SANITIZER
  1168. def_bool y
  1169. prompt "MTRR cleanup support"
  1170. depends on MTRR
  1171. ---help---
  1172. Convert MTRR layout from continuous to discrete, so X drivers can
  1173. add writeback entries.
  1174. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1175. The largest mtrr entry size for a continuous block can be set with
  1176. mtrr_chunk_size.
  1177. If unsure, say Y.
  1178. config MTRR_SANITIZER_ENABLE_DEFAULT
  1179. int "MTRR cleanup enable value (0-1)"
  1180. range 0 1
  1181. default "0"
  1182. depends on MTRR_SANITIZER
  1183. ---help---
  1184. Enable mtrr cleanup default value
  1185. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1186. int "MTRR cleanup spare reg num (0-7)"
  1187. range 0 7
  1188. default "1"
  1189. depends on MTRR_SANITIZER
  1190. ---help---
  1191. mtrr cleanup spare entries default, it can be changed via
  1192. mtrr_spare_reg_nr=N on the kernel command line.
  1193. config X86_PAT
  1194. def_bool y
  1195. prompt "x86 PAT support" if EXPERT
  1196. depends on MTRR
  1197. ---help---
  1198. Use PAT attributes to setup page level cache control.
  1199. PATs are the modern equivalents of MTRRs and are much more
  1200. flexible than MTRRs.
  1201. Say N here if you see bootup problems (boot crash, boot hang,
  1202. spontaneous reboots) or a non-working video driver.
  1203. If unsure, say Y.
  1204. config ARCH_USES_PG_UNCACHED
  1205. def_bool y
  1206. depends on X86_PAT
  1207. config EFI
  1208. bool "EFI runtime service support"
  1209. depends on ACPI
  1210. ---help---
  1211. This enables the kernel to use EFI runtime services that are
  1212. available (such as the EFI variable services).
  1213. This option is only useful on systems that have EFI firmware.
  1214. In addition, you should use the latest ELILO loader available
  1215. at <http://elilo.sourceforge.net> in order to take advantage
  1216. of EFI runtime services. However, even with this option, the
  1217. resultant kernel should continue to boot on existing non-EFI
  1218. platforms.
  1219. config SECCOMP
  1220. def_bool y
  1221. prompt "Enable seccomp to safely compute untrusted bytecode"
  1222. ---help---
  1223. This kernel feature is useful for number crunching applications
  1224. that may need to compute untrusted bytecode during their
  1225. execution. By using pipes or other transports made available to
  1226. the process as file descriptors supporting the read/write
  1227. syscalls, it's possible to isolate those applications in
  1228. their own address space using seccomp. Once seccomp is
  1229. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1230. and the task is only allowed to execute a few safe syscalls
  1231. defined by each seccomp mode.
  1232. If unsure, say Y. Only embedded should say N here.
  1233. config CC_STACKPROTECTOR
  1234. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1235. ---help---
  1236. This option turns on the -fstack-protector GCC feature. This
  1237. feature puts, at the beginning of functions, a canary value on
  1238. the stack just before the return address, and validates
  1239. the value just before actually returning. Stack based buffer
  1240. overflows (that need to overwrite this return address) now also
  1241. overwrite the canary, which gets detected and the attack is then
  1242. neutralized via a kernel panic.
  1243. This feature requires gcc version 4.2 or above, or a distribution
  1244. gcc with the feature backported. Older versions are automatically
  1245. detected and for those versions, this configuration option is
  1246. ignored. (and a warning is printed during bootup)
  1247. source kernel/Kconfig.hz
  1248. config KEXEC
  1249. bool "kexec system call"
  1250. ---help---
  1251. kexec is a system call that implements the ability to shutdown your
  1252. current kernel, and to start another kernel. It is like a reboot
  1253. but it is independent of the system firmware. And like a reboot
  1254. you can start any kernel with it, not just Linux.
  1255. The name comes from the similarity to the exec system call.
  1256. It is an ongoing process to be certain the hardware in a machine
  1257. is properly shutdown, so do not be surprised if this code does not
  1258. initially work for you. It may help to enable device hotplugging
  1259. support. As of this writing the exact hardware interface is
  1260. strongly in flux, so no good recommendation can be made.
  1261. config CRASH_DUMP
  1262. bool "kernel crash dumps"
  1263. depends on X86_64 || (X86_32 && HIGHMEM)
  1264. ---help---
  1265. Generate crash dump after being started by kexec.
  1266. This should be normally only set in special crash dump kernels
  1267. which are loaded in the main kernel with kexec-tools into
  1268. a specially reserved region and then later executed after
  1269. a crash by kdump/kexec. The crash dump kernel must be compiled
  1270. to a memory address not used by the main kernel or BIOS using
  1271. PHYSICAL_START, or it must be built as a relocatable image
  1272. (CONFIG_RELOCATABLE=y).
  1273. For more details see Documentation/kdump/kdump.txt
  1274. config KEXEC_JUMP
  1275. bool "kexec jump (EXPERIMENTAL)"
  1276. depends on EXPERIMENTAL
  1277. depends on KEXEC && HIBERNATION
  1278. ---help---
  1279. Jump between original kernel and kexeced kernel and invoke
  1280. code in physical address mode via KEXEC
  1281. config PHYSICAL_START
  1282. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1283. default "0x1000000"
  1284. ---help---
  1285. This gives the physical address where the kernel is loaded.
  1286. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1287. bzImage will decompress itself to above physical address and
  1288. run from there. Otherwise, bzImage will run from the address where
  1289. it has been loaded by the boot loader and will ignore above physical
  1290. address.
  1291. In normal kdump cases one does not have to set/change this option
  1292. as now bzImage can be compiled as a completely relocatable image
  1293. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1294. address. This option is mainly useful for the folks who don't want
  1295. to use a bzImage for capturing the crash dump and want to use a
  1296. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1297. to be specifically compiled to run from a specific memory area
  1298. (normally a reserved region) and this option comes handy.
  1299. So if you are using bzImage for capturing the crash dump,
  1300. leave the value here unchanged to 0x1000000 and set
  1301. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1302. for capturing the crash dump change this value to start of
  1303. the reserved region. In other words, it can be set based on
  1304. the "X" value as specified in the "crashkernel=YM@XM"
  1305. command line boot parameter passed to the panic-ed
  1306. kernel. Please take a look at Documentation/kdump/kdump.txt
  1307. for more details about crash dumps.
  1308. Usage of bzImage for capturing the crash dump is recommended as
  1309. one does not have to build two kernels. Same kernel can be used
  1310. as production kernel and capture kernel. Above option should have
  1311. gone away after relocatable bzImage support is introduced. But it
  1312. is present because there are users out there who continue to use
  1313. vmlinux for dump capture. This option should go away down the
  1314. line.
  1315. Don't change this unless you know what you are doing.
  1316. config RELOCATABLE
  1317. bool "Build a relocatable kernel"
  1318. default y
  1319. ---help---
  1320. This builds a kernel image that retains relocation information
  1321. so it can be loaded someplace besides the default 1MB.
  1322. The relocations tend to make the kernel binary about 10% larger,
  1323. but are discarded at runtime.
  1324. One use is for the kexec on panic case where the recovery kernel
  1325. must live at a different physical address than the primary
  1326. kernel.
  1327. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1328. it has been loaded at and the compile time physical address
  1329. (CONFIG_PHYSICAL_START) is ignored.
  1330. # Relocation on x86-32 needs some additional build support
  1331. config X86_NEED_RELOCS
  1332. def_bool y
  1333. depends on X86_32 && RELOCATABLE
  1334. config PHYSICAL_ALIGN
  1335. hex "Alignment value to which kernel should be aligned" if X86_32
  1336. default "0x1000000"
  1337. range 0x2000 0x1000000
  1338. ---help---
  1339. This value puts the alignment restrictions on physical address
  1340. where kernel is loaded and run from. Kernel is compiled for an
  1341. address which meets above alignment restriction.
  1342. If bootloader loads the kernel at a non-aligned address and
  1343. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1344. address aligned to above value and run from there.
  1345. If bootloader loads the kernel at a non-aligned address and
  1346. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1347. load address and decompress itself to the address it has been
  1348. compiled for and run from there. The address for which kernel is
  1349. compiled already meets above alignment restrictions. Hence the
  1350. end result is that kernel runs from a physical address meeting
  1351. above alignment restrictions.
  1352. Don't change this unless you know what you are doing.
  1353. config HOTPLUG_CPU
  1354. bool "Support for hot-pluggable CPUs"
  1355. depends on SMP && HOTPLUG
  1356. ---help---
  1357. Say Y here to allow turning CPUs off and on. CPUs can be
  1358. controlled through /sys/devices/system/cpu.
  1359. ( Note: power management support will enable this option
  1360. automatically on SMP systems. )
  1361. Say N if you want to disable CPU hotplug.
  1362. config COMPAT_VDSO
  1363. def_bool y
  1364. prompt "Compat VDSO support"
  1365. depends on X86_32 || IA32_EMULATION
  1366. ---help---
  1367. Map the 32-bit VDSO to the predictable old-style address too.
  1368. Say N here if you are running a sufficiently recent glibc
  1369. version (2.3.3 or later), to remove the high-mapped
  1370. VDSO mapping and to exclusively use the randomized VDSO.
  1371. If unsure, say Y.
  1372. config CMDLINE_BOOL
  1373. bool "Built-in kernel command line"
  1374. ---help---
  1375. Allow for specifying boot arguments to the kernel at
  1376. build time. On some systems (e.g. embedded ones), it is
  1377. necessary or convenient to provide some or all of the
  1378. kernel boot arguments with the kernel itself (that is,
  1379. to not rely on the boot loader to provide them.)
  1380. To compile command line arguments into the kernel,
  1381. set this option to 'Y', then fill in the
  1382. the boot arguments in CONFIG_CMDLINE.
  1383. Systems with fully functional boot loaders (i.e. non-embedded)
  1384. should leave this option set to 'N'.
  1385. config CMDLINE
  1386. string "Built-in kernel command string"
  1387. depends on CMDLINE_BOOL
  1388. default ""
  1389. ---help---
  1390. Enter arguments here that should be compiled into the kernel
  1391. image and used at boot time. If the boot loader provides a
  1392. command line at boot time, it is appended to this string to
  1393. form the full kernel command line, when the system boots.
  1394. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1395. change this behavior.
  1396. In most cases, the command line (whether built-in or provided
  1397. by the boot loader) should specify the device for the root
  1398. file system.
  1399. config CMDLINE_OVERRIDE
  1400. bool "Built-in command line overrides boot loader arguments"
  1401. depends on CMDLINE_BOOL
  1402. ---help---
  1403. Set this option to 'Y' to have the kernel ignore the boot loader
  1404. command line, and use ONLY the built-in command line.
  1405. This is used to work around broken boot loaders. This should
  1406. be set to 'N' under normal conditions.
  1407. endmenu
  1408. config ARCH_ENABLE_MEMORY_HOTPLUG
  1409. def_bool y
  1410. depends on X86_64 || (X86_32 && HIGHMEM)
  1411. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1412. def_bool y
  1413. depends on MEMORY_HOTPLUG
  1414. config USE_PERCPU_NUMA_NODE_ID
  1415. def_bool y
  1416. depends on NUMA
  1417. menu "Power management and ACPI options"
  1418. config ARCH_HIBERNATION_HEADER
  1419. def_bool y
  1420. depends on X86_64 && HIBERNATION
  1421. source "kernel/power/Kconfig"
  1422. source "drivers/acpi/Kconfig"
  1423. source "drivers/sfi/Kconfig"
  1424. config X86_APM_BOOT
  1425. def_bool y
  1426. depends on APM || APM_MODULE
  1427. menuconfig APM
  1428. tristate "APM (Advanced Power Management) BIOS support"
  1429. depends on X86_32 && PM_SLEEP
  1430. ---help---
  1431. APM is a BIOS specification for saving power using several different
  1432. techniques. This is mostly useful for battery powered laptops with
  1433. APM compliant BIOSes. If you say Y here, the system time will be
  1434. reset after a RESUME operation, the /proc/apm device will provide
  1435. battery status information, and user-space programs will receive
  1436. notification of APM "events" (e.g. battery status change).
  1437. If you select "Y" here, you can disable actual use of the APM
  1438. BIOS by passing the "apm=off" option to the kernel at boot time.
  1439. Note that the APM support is almost completely disabled for
  1440. machines with more than one CPU.
  1441. In order to use APM, you will need supporting software. For location
  1442. and more information, read <file:Documentation/power/pm.txt> and the
  1443. Battery Powered Linux mini-HOWTO, available from
  1444. <http://www.tldp.org/docs.html#howto>.
  1445. This driver does not spin down disk drives (see the hdparm(8)
  1446. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1447. VESA-compliant "green" monitors.
  1448. This driver does not support the TI 4000M TravelMate and the ACER
  1449. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1450. desktop machines also don't have compliant BIOSes, and this driver
  1451. may cause those machines to panic during the boot phase.
  1452. Generally, if you don't have a battery in your machine, there isn't
  1453. much point in using this driver and you should say N. If you get
  1454. random kernel OOPSes or reboots that don't seem to be related to
  1455. anything, try disabling/enabling this option (or disabling/enabling
  1456. APM in your BIOS).
  1457. Some other things you should try when experiencing seemingly random,
  1458. "weird" problems:
  1459. 1) make sure that you have enough swap space and that it is
  1460. enabled.
  1461. 2) pass the "no-hlt" option to the kernel
  1462. 3) switch on floating point emulation in the kernel and pass
  1463. the "no387" option to the kernel
  1464. 4) pass the "floppy=nodma" option to the kernel
  1465. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1466. all but the first 4 MB of RAM)
  1467. 6) make sure that the CPU is not over clocked.
  1468. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1469. 8) disable the cache from your BIOS settings
  1470. 9) install a fan for the video card or exchange video RAM
  1471. 10) install a better fan for the CPU
  1472. 11) exchange RAM chips
  1473. 12) exchange the motherboard.
  1474. To compile this driver as a module, choose M here: the
  1475. module will be called apm.
  1476. if APM
  1477. config APM_IGNORE_USER_SUSPEND
  1478. bool "Ignore USER SUSPEND"
  1479. ---help---
  1480. This option will ignore USER SUSPEND requests. On machines with a
  1481. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1482. series notebooks, it is necessary to say Y because of a BIOS bug.
  1483. config APM_DO_ENABLE
  1484. bool "Enable PM at boot time"
  1485. ---help---
  1486. Enable APM features at boot time. From page 36 of the APM BIOS
  1487. specification: "When disabled, the APM BIOS does not automatically
  1488. power manage devices, enter the Standby State, enter the Suspend
  1489. State, or take power saving steps in response to CPU Idle calls."
  1490. This driver will make CPU Idle calls when Linux is idle (unless this
  1491. feature is turned off -- see "Do CPU IDLE calls", below). This
  1492. should always save battery power, but more complicated APM features
  1493. will be dependent on your BIOS implementation. You may need to turn
  1494. this option off if your computer hangs at boot time when using APM
  1495. support, or if it beeps continuously instead of suspending. Turn
  1496. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1497. T400CDT. This is off by default since most machines do fine without
  1498. this feature.
  1499. config APM_CPU_IDLE
  1500. bool "Make CPU Idle calls when idle"
  1501. ---help---
  1502. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1503. On some machines, this can activate improved power savings, such as
  1504. a slowed CPU clock rate, when the machine is idle. These idle calls
  1505. are made after the idle loop has run for some length of time (e.g.,
  1506. 333 mS). On some machines, this will cause a hang at boot time or
  1507. whenever the CPU becomes idle. (On machines with more than one CPU,
  1508. this option does nothing.)
  1509. config APM_DISPLAY_BLANK
  1510. bool "Enable console blanking using APM"
  1511. ---help---
  1512. Enable console blanking using the APM. Some laptops can use this to
  1513. turn off the LCD backlight when the screen blanker of the Linux
  1514. virtual console blanks the screen. Note that this is only used by
  1515. the virtual console screen blanker, and won't turn off the backlight
  1516. when using the X Window system. This also doesn't have anything to
  1517. do with your VESA-compliant power-saving monitor. Further, this
  1518. option doesn't work for all laptops -- it might not turn off your
  1519. backlight at all, or it might print a lot of errors to the console,
  1520. especially if you are using gpm.
  1521. config APM_ALLOW_INTS
  1522. bool "Allow interrupts during APM BIOS calls"
  1523. ---help---
  1524. Normally we disable external interrupts while we are making calls to
  1525. the APM BIOS as a measure to lessen the effects of a badly behaving
  1526. BIOS implementation. The BIOS should reenable interrupts if it
  1527. needs to. Unfortunately, some BIOSes do not -- especially those in
  1528. many of the newer IBM Thinkpads. If you experience hangs when you
  1529. suspend, try setting this to Y. Otherwise, say N.
  1530. endif # APM
  1531. source "drivers/cpufreq/Kconfig"
  1532. source "drivers/cpuidle/Kconfig"
  1533. source "drivers/idle/Kconfig"
  1534. endmenu
  1535. menu "Bus options (PCI etc.)"
  1536. config PCI
  1537. bool "PCI support"
  1538. default y
  1539. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1540. ---help---
  1541. Find out whether you have a PCI motherboard. PCI is the name of a
  1542. bus system, i.e. the way the CPU talks to the other stuff inside
  1543. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1544. VESA. If you have PCI, say Y, otherwise N.
  1545. choice
  1546. prompt "PCI access mode"
  1547. depends on X86_32 && PCI
  1548. default PCI_GOANY
  1549. ---help---
  1550. On PCI systems, the BIOS can be used to detect the PCI devices and
  1551. determine their configuration. However, some old PCI motherboards
  1552. have BIOS bugs and may crash if this is done. Also, some embedded
  1553. PCI-based systems don't have any BIOS at all. Linux can also try to
  1554. detect the PCI hardware directly without using the BIOS.
  1555. With this option, you can specify how Linux should detect the
  1556. PCI devices. If you choose "BIOS", the BIOS will be used,
  1557. if you choose "Direct", the BIOS won't be used, and if you
  1558. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1559. If you choose "Any", the kernel will try MMCONFIG, then the
  1560. direct access method and falls back to the BIOS if that doesn't
  1561. work. If unsure, go with the default, which is "Any".
  1562. config PCI_GOBIOS
  1563. bool "BIOS"
  1564. config PCI_GOMMCONFIG
  1565. bool "MMConfig"
  1566. config PCI_GODIRECT
  1567. bool "Direct"
  1568. config PCI_GOOLPC
  1569. bool "OLPC XO-1"
  1570. depends on OLPC
  1571. config PCI_GOANY
  1572. bool "Any"
  1573. endchoice
  1574. config PCI_BIOS
  1575. def_bool y
  1576. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1577. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1578. config PCI_DIRECT
  1579. def_bool y
  1580. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1581. config PCI_MMCONFIG
  1582. def_bool y
  1583. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1584. config PCI_OLPC
  1585. def_bool y
  1586. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1587. config PCI_XEN
  1588. def_bool y
  1589. depends on PCI && XEN
  1590. select SWIOTLB_XEN
  1591. config PCI_DOMAINS
  1592. def_bool y
  1593. depends on PCI
  1594. config PCI_MMCONFIG
  1595. bool "Support mmconfig PCI config space access"
  1596. depends on X86_64 && PCI && ACPI
  1597. config PCI_CNB20LE_QUIRK
  1598. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  1599. default n
  1600. depends on PCI && EXPERIMENTAL
  1601. help
  1602. Read the PCI windows out of the CNB20LE host bridge. This allows
  1603. PCI hotplug to work on systems with the CNB20LE chipset which do
  1604. not have ACPI.
  1605. There's no public spec for this chipset, and this functionality
  1606. is known to be incomplete.
  1607. You should say N unless you know you need this.
  1608. config DMAR
  1609. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1610. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1611. help
  1612. DMA remapping (DMAR) devices support enables independent address
  1613. translations for Direct Memory Access (DMA) from devices.
  1614. These DMA remapping devices are reported via ACPI tables
  1615. and include PCI device scope covered by these DMA
  1616. remapping devices.
  1617. config DMAR_DEFAULT_ON
  1618. def_bool y
  1619. prompt "Enable DMA Remapping Devices by default"
  1620. depends on DMAR
  1621. help
  1622. Selecting this option will enable a DMAR device at boot time if
  1623. one is found. If this option is not selected, DMAR support can
  1624. be enabled by passing intel_iommu=on to the kernel. It is
  1625. recommended you say N here while the DMAR code remains
  1626. experimental.
  1627. config DMAR_BROKEN_GFX_WA
  1628. bool "Workaround broken graphics drivers (going away soon)"
  1629. depends on DMAR && BROKEN
  1630. ---help---
  1631. Current Graphics drivers tend to use physical address
  1632. for DMA and avoid using DMA APIs. Setting this config
  1633. option permits the IOMMU driver to set a unity map for
  1634. all the OS-visible memory. Hence the driver can continue
  1635. to use physical addresses for DMA, at least until this
  1636. option is removed in the 2.6.32 kernel.
  1637. config DMAR_FLOPPY_WA
  1638. def_bool y
  1639. depends on DMAR
  1640. ---help---
  1641. Floppy disk drivers are known to bypass DMA API calls
  1642. thereby failing to work when IOMMU is enabled. This
  1643. workaround will setup a 1:1 mapping for the first
  1644. 16MiB to make floppy (an ISA device) work.
  1645. config INTR_REMAP
  1646. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1647. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1648. ---help---
  1649. Supports Interrupt remapping for IO-APIC and MSI devices.
  1650. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1651. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1652. source "drivers/pci/pcie/Kconfig"
  1653. source "drivers/pci/Kconfig"
  1654. # x86_64 have no ISA slots, but can have ISA-style DMA.
  1655. config ISA_DMA_API
  1656. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  1657. default y
  1658. help
  1659. Enables ISA-style DMA support for devices requiring such controllers.
  1660. If unsure, say Y.
  1661. if X86_32
  1662. config ISA
  1663. bool "ISA support"
  1664. ---help---
  1665. Find out whether you have ISA slots on your motherboard. ISA is the
  1666. name of a bus system, i.e. the way the CPU talks to the other stuff
  1667. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1668. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1669. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1670. config EISA
  1671. bool "EISA support"
  1672. depends on ISA
  1673. ---help---
  1674. The Extended Industry Standard Architecture (EISA) bus was
  1675. developed as an open alternative to the IBM MicroChannel bus.
  1676. The EISA bus provided some of the features of the IBM MicroChannel
  1677. bus while maintaining backward compatibility with cards made for
  1678. the older ISA bus. The EISA bus saw limited use between 1988 and
  1679. 1995 when it was made obsolete by the PCI bus.
  1680. Say Y here if you are building a kernel for an EISA-based machine.
  1681. Otherwise, say N.
  1682. source "drivers/eisa/Kconfig"
  1683. config MCA
  1684. bool "MCA support"
  1685. ---help---
  1686. MicroChannel Architecture is found in some IBM PS/2 machines and
  1687. laptops. It is a bus system similar to PCI or ISA. See
  1688. <file:Documentation/mca.txt> (and especially the web page given
  1689. there) before attempting to build an MCA bus kernel.
  1690. source "drivers/mca/Kconfig"
  1691. config SCx200
  1692. tristate "NatSemi SCx200 support"
  1693. ---help---
  1694. This provides basic support for National Semiconductor's
  1695. (now AMD's) Geode processors. The driver probes for the
  1696. PCI-IDs of several on-chip devices, so its a good dependency
  1697. for other scx200_* drivers.
  1698. If compiled as a module, the driver is named scx200.
  1699. config SCx200HR_TIMER
  1700. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1701. depends on SCx200
  1702. default y
  1703. ---help---
  1704. This driver provides a clocksource built upon the on-chip
  1705. 27MHz high-resolution timer. Its also a workaround for
  1706. NSC Geode SC-1100's buggy TSC, which loses time when the
  1707. processor goes idle (as is done by the scheduler). The
  1708. other workaround is idle=poll boot option.
  1709. config OLPC
  1710. bool "One Laptop Per Child support"
  1711. depends on !X86_PAE
  1712. select GPIOLIB
  1713. select OF
  1714. select OF_PROMTREE
  1715. ---help---
  1716. Add support for detecting the unique features of the OLPC
  1717. XO hardware.
  1718. config OLPC_XO1
  1719. tristate "OLPC XO-1 support"
  1720. depends on OLPC && MFD_CS5535
  1721. ---help---
  1722. Add support for non-essential features of the OLPC XO-1 laptop.
  1723. endif # X86_32
  1724. config AMD_NB
  1725. def_bool y
  1726. depends on CPU_SUP_AMD && PCI
  1727. source "drivers/pcmcia/Kconfig"
  1728. source "drivers/pci/hotplug/Kconfig"
  1729. config RAPIDIO
  1730. bool "RapidIO support"
  1731. depends on PCI
  1732. default n
  1733. help
  1734. If you say Y here, the kernel will include drivers and
  1735. infrastructure code to support RapidIO interconnect devices.
  1736. source "drivers/rapidio/Kconfig"
  1737. endmenu
  1738. menu "Executable file formats / Emulations"
  1739. source "fs/Kconfig.binfmt"
  1740. config IA32_EMULATION
  1741. bool "IA32 Emulation"
  1742. depends on X86_64
  1743. select COMPAT_BINFMT_ELF
  1744. ---help---
  1745. Include code to run 32-bit programs under a 64-bit kernel. You should
  1746. likely turn this on, unless you're 100% sure that you don't have any
  1747. 32-bit programs left.
  1748. config IA32_AOUT
  1749. tristate "IA32 a.out support"
  1750. depends on IA32_EMULATION
  1751. ---help---
  1752. Support old a.out binaries in the 32bit emulation.
  1753. config COMPAT
  1754. def_bool y
  1755. depends on IA32_EMULATION
  1756. config COMPAT_FOR_U64_ALIGNMENT
  1757. def_bool COMPAT
  1758. depends on X86_64
  1759. config SYSVIPC_COMPAT
  1760. def_bool y
  1761. depends on COMPAT && SYSVIPC
  1762. config KEYS_COMPAT
  1763. bool
  1764. depends on COMPAT && KEYS
  1765. default y
  1766. endmenu
  1767. config HAVE_ATOMIC_IOMAP
  1768. def_bool y
  1769. depends on X86_32
  1770. config HAVE_TEXT_POKE_SMP
  1771. bool
  1772. select STOP_MACHINE if SMP
  1773. source "net/Kconfig"
  1774. source "drivers/Kconfig"
  1775. source "drivers/firmware/Kconfig"
  1776. source "fs/Kconfig"
  1777. source "arch/x86/Kconfig.debug"
  1778. source "security/Kconfig"
  1779. source "crypto/Kconfig"
  1780. source "arch/x86/kvm/Kconfig"
  1781. source "lib/Kconfig"