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_IRQ_PROBE
  65. select GENERIC_PENDING_IRQ if SMP
  66. select GENERIC_IRQ_SHOW
  67. select IRQ_FORCED_THREADING
  68. select USE_GENERIC_SMP_HELPERS if SMP
  69. select HAVE_BPF_JIT if (X86_64 && NET)
  70. config INSTRUCTION_DECODER
  71. def_bool (KPROBES || PERF_EVENTS)
  72. config OUTPUT_FORMAT
  73. string
  74. default "elf32-i386" if X86_32
  75. default "elf64-x86-64" if X86_64
  76. config ARCH_DEFCONFIG
  77. string
  78. default "arch/x86/configs/i386_defconfig" if X86_32
  79. default "arch/x86/configs/x86_64_defconfig" if X86_64
  80. config GENERIC_CMOS_UPDATE
  81. def_bool y
  82. config CLOCKSOURCE_WATCHDOG
  83. def_bool y
  84. config GENERIC_CLOCKEVENTS
  85. def_bool y
  86. config GENERIC_CLOCKEVENTS_BROADCAST
  87. def_bool y
  88. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  89. config LOCKDEP_SUPPORT
  90. def_bool y
  91. config STACKTRACE_SUPPORT
  92. def_bool y
  93. config HAVE_LATENCYTOP_SUPPORT
  94. def_bool y
  95. config MMU
  96. def_bool y
  97. config ZONE_DMA
  98. bool "DMA memory allocation support" if EXPERT
  99. default y
  100. help
  101. DMA memory allocation support allows devices with less than 32-bit
  102. addressing to allocate within the first 16MB of address space.
  103. Disable if no such devices will be used.
  104. If unsure, say Y.
  105. config SBUS
  106. bool
  107. config NEED_DMA_MAP_STATE
  108. def_bool (X86_64 || DMAR || DMA_API_DEBUG)
  109. config NEED_SG_DMA_LENGTH
  110. def_bool y
  111. config GENERIC_ISA_DMA
  112. def_bool ISA_DMA_API
  113. config GENERIC_IOMAP
  114. def_bool y
  115. config GENERIC_BUG
  116. def_bool y
  117. depends on BUG
  118. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  119. config GENERIC_BUG_RELATIVE_POINTERS
  120. bool
  121. config GENERIC_HWEIGHT
  122. def_bool y
  123. config GENERIC_GPIO
  124. bool
  125. config ARCH_MAY_HAVE_PC_FDC
  126. def_bool ISA_DMA_API
  127. config RWSEM_GENERIC_SPINLOCK
  128. def_bool !X86_XADD
  129. config RWSEM_XCHGADD_ALGORITHM
  130. def_bool X86_XADD
  131. config ARCH_HAS_CPU_IDLE_WAIT
  132. def_bool y
  133. config GENERIC_CALIBRATE_DELAY
  134. def_bool y
  135. config GENERIC_TIME_VSYSCALL
  136. bool
  137. default X86_64
  138. config ARCH_HAS_CPU_RELAX
  139. def_bool y
  140. config ARCH_HAS_DEFAULT_IDLE
  141. def_bool y
  142. config ARCH_HAS_CACHE_LINE_SIZE
  143. def_bool y
  144. config HAVE_SETUP_PER_CPU_AREA
  145. def_bool y
  146. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  147. def_bool y
  148. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  149. def_bool y
  150. config HAVE_CPUMASK_OF_CPU_MAP
  151. def_bool X86_64_SMP
  152. config ARCH_HIBERNATION_POSSIBLE
  153. def_bool y
  154. config ARCH_SUSPEND_POSSIBLE
  155. def_bool y
  156. config ZONE_DMA32
  157. bool
  158. default X86_64
  159. config ARCH_POPULATES_NODE_MAP
  160. def_bool y
  161. config AUDIT_ARCH
  162. bool
  163. default X86_64
  164. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  165. def_bool y
  166. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  167. def_bool y
  168. config HAVE_INTEL_TXT
  169. def_bool y
  170. depends on EXPERIMENTAL && DMAR && ACPI
  171. config X86_32_SMP
  172. def_bool y
  173. depends on X86_32 && SMP
  174. config X86_64_SMP
  175. def_bool y
  176. depends on X86_64 && SMP
  177. config X86_HT
  178. def_bool y
  179. depends on SMP
  180. config X86_32_LAZY_GS
  181. def_bool y
  182. depends on X86_32 && !CC_STACKPROTECTOR
  183. config ARCH_HWEIGHT_CFLAGS
  184. string
  185. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  186. 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
  187. config KTIME_SCALAR
  188. def_bool X86_32
  189. config ARCH_CPU_PROBE_RELEASE
  190. def_bool y
  191. depends on HOTPLUG_CPU
  192. source "init/Kconfig"
  193. source "kernel/Kconfig.freezer"
  194. menu "Processor type and features"
  195. source "kernel/time/Kconfig"
  196. config SMP
  197. bool "Symmetric multi-processing support"
  198. ---help---
  199. This enables support for systems with more than one CPU. If you have
  200. a system with only one CPU, like most personal computers, say N. If
  201. you have a system with more than one CPU, say Y.
  202. If you say N here, the kernel will run on single and multiprocessor
  203. machines, but will use only one CPU of a multiprocessor machine. If
  204. you say Y here, the kernel will run on many, but not all,
  205. singleprocessor machines. On a singleprocessor machine, the kernel
  206. will run faster if you say N here.
  207. Note that if you say Y here and choose architecture "586" or
  208. "Pentium" under "Processor family", the kernel will not work on 486
  209. architectures. Similarly, multiprocessor kernels for the "PPro"
  210. architecture may not work on all Pentium based boards.
  211. People using multiprocessor machines who say Y here should also say
  212. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  213. Management" code will be disabled if you say Y here.
  214. See also <file:Documentation/i386/IO-APIC.txt>,
  215. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  216. <http://www.tldp.org/docs.html#howto>.
  217. If you don't know what to do here, say N.
  218. config X86_X2APIC
  219. bool "Support x2apic"
  220. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  221. ---help---
  222. This enables x2apic support on CPUs that have this feature.
  223. This allows 32-bit apic IDs (so it can support very large systems),
  224. and accesses the local apic via MSRs not via mmio.
  225. If you don't know what to do here, say N.
  226. config X86_MPPARSE
  227. bool "Enable MPS table" if ACPI
  228. default y
  229. depends on X86_LOCAL_APIC
  230. ---help---
  231. For old smp systems that do not have proper acpi support. Newer systems
  232. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  233. config X86_BIGSMP
  234. bool "Support for big SMP systems with more than 8 CPUs"
  235. depends on X86_32 && SMP
  236. ---help---
  237. This option is needed for the systems that have more than 8 CPUs
  238. if X86_32
  239. config X86_EXTENDED_PLATFORM
  240. bool "Support for extended (non-PC) x86 platforms"
  241. default y
  242. ---help---
  243. If you disable this option then the kernel will only support
  244. standard PC platforms. (which covers the vast majority of
  245. systems out there.)
  246. If you enable this option then you'll be able to select support
  247. for the following (non-PC) 32 bit x86 platforms:
  248. AMD Elan
  249. NUMAQ (IBM/Sequent)
  250. RDC R-321x SoC
  251. SGI 320/540 (Visual Workstation)
  252. Summit/EXA (IBM x440)
  253. Unisys ES7000 IA32 series
  254. Moorestown MID devices
  255. If you have one of these systems, or if you want to build a
  256. generic distribution kernel, say Y here - otherwise say N.
  257. endif
  258. if X86_64
  259. config X86_EXTENDED_PLATFORM
  260. bool "Support for extended (non-PC) x86 platforms"
  261. default y
  262. ---help---
  263. If you disable this option then the kernel will only support
  264. standard PC platforms. (which covers the vast majority of
  265. systems out there.)
  266. If you enable this option then you'll be able to select support
  267. for the following (non-PC) 64 bit x86 platforms:
  268. ScaleMP vSMP
  269. SGI Ultraviolet
  270. If you have one of these systems, or if you want to build a
  271. generic distribution kernel, say Y here - otherwise say N.
  272. endif
  273. # This is an alphabetically sorted list of 64 bit extended platforms
  274. # Please maintain the alphabetic order if and when there are additions
  275. config X86_VSMP
  276. bool "ScaleMP vSMP"
  277. select PARAVIRT_GUEST
  278. select PARAVIRT
  279. depends on X86_64 && PCI
  280. depends on X86_EXTENDED_PLATFORM
  281. ---help---
  282. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  283. supposed to run on these EM64T-based machines. Only choose this option
  284. if you have one of these machines.
  285. config X86_UV
  286. bool "SGI Ultraviolet"
  287. depends on X86_64
  288. depends on X86_EXTENDED_PLATFORM
  289. depends on NUMA
  290. depends on X86_X2APIC
  291. ---help---
  292. This option is needed in order to support SGI Ultraviolet systems.
  293. If you don't have one of these, you should say N here.
  294. # Following is an alphabetically sorted list of 32 bit extended platforms
  295. # Please maintain the alphabetic order if and when there are additions
  296. config X86_INTEL_CE
  297. bool "CE4100 TV platform"
  298. depends on PCI
  299. depends on PCI_GODIRECT
  300. depends on X86_32
  301. depends on X86_EXTENDED_PLATFORM
  302. select X86_REBOOTFIXUPS
  303. select OF
  304. select OF_EARLY_FLATTREE
  305. ---help---
  306. Select for the Intel CE media processor (CE4100) SOC.
  307. This option compiles in support for the CE4100 SOC for settop
  308. boxes and media devices.
  309. config X86_INTEL_MID
  310. bool "Intel MID platform support"
  311. depends on X86_32
  312. depends on X86_EXTENDED_PLATFORM
  313. ---help---
  314. Select to build a kernel capable of supporting Intel MID platform
  315. systems which do not have the PCI legacy interfaces (Moorestown,
  316. Medfield). If you are building for a PC class system say N here.
  317. if X86_INTEL_MID
  318. config X86_MRST
  319. bool "Moorestown MID platform"
  320. depends on PCI
  321. depends on PCI_GOANY
  322. depends on X86_IO_APIC
  323. select APB_TIMER
  324. select I2C
  325. select SPI
  326. select INTEL_SCU_IPC
  327. select X86_PLATFORM_DEVICES
  328. ---help---
  329. Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
  330. Internet Device(MID) platform. Moorestown consists of two chips:
  331. Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
  332. Unlike standard x86 PCs, Moorestown does not have many legacy devices
  333. nor standard legacy replacement devices/features. e.g. Moorestown does
  334. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  335. endif
  336. config X86_RDC321X
  337. bool "RDC R-321x SoC"
  338. depends on X86_32
  339. depends on X86_EXTENDED_PLATFORM
  340. select M486
  341. select X86_REBOOTFIXUPS
  342. ---help---
  343. This option is needed for RDC R-321x system-on-chip, also known
  344. as R-8610-(G).
  345. If you don't have one of these chips, you should say N here.
  346. config X86_32_NON_STANDARD
  347. bool "Support non-standard 32-bit SMP architectures"
  348. depends on X86_32 && SMP
  349. depends on X86_EXTENDED_PLATFORM
  350. ---help---
  351. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  352. subarchitectures. It is intended for a generic binary kernel.
  353. if you select them all, kernel will probe it one by one. and will
  354. fallback to default.
  355. # Alphabetically sorted list of Non standard 32 bit platforms
  356. config X86_NUMAQ
  357. bool "NUMAQ (IBM/Sequent)"
  358. depends on X86_32_NON_STANDARD
  359. depends on PCI
  360. select NUMA
  361. select X86_MPPARSE
  362. ---help---
  363. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  364. NUMA multiquad box. This changes the way that processors are
  365. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  366. of Flat Logical. You will need a new lynxer.elf file to flash your
  367. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  368. config X86_SUPPORTS_MEMORY_FAILURE
  369. def_bool y
  370. # MCE code calls memory_failure():
  371. depends on X86_MCE
  372. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  373. depends on !X86_NUMAQ
  374. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  375. depends on X86_64 || !SPARSEMEM
  376. select ARCH_SUPPORTS_MEMORY_FAILURE
  377. config X86_VISWS
  378. bool "SGI 320/540 (Visual Workstation)"
  379. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  380. depends on X86_32_NON_STANDARD
  381. ---help---
  382. The SGI Visual Workstation series is an IA32-based workstation
  383. based on SGI systems chips with some legacy PC hardware attached.
  384. Say Y here to create a kernel to run on the SGI 320 or 540.
  385. A kernel compiled for the Visual Workstation will run on general
  386. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  387. config X86_SUMMIT
  388. bool "Summit/EXA (IBM x440)"
  389. depends on X86_32_NON_STANDARD
  390. ---help---
  391. This option is needed for IBM systems that use the Summit/EXA chipset.
  392. In particular, it is needed for the x440.
  393. config X86_ES7000
  394. bool "Unisys ES7000 IA32 series"
  395. depends on X86_32_NON_STANDARD && X86_BIGSMP
  396. ---help---
  397. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  398. supposed to run on an IA32-based Unisys ES7000 system.
  399. config X86_32_IRIS
  400. tristate "Eurobraille/Iris poweroff module"
  401. depends on X86_32
  402. ---help---
  403. The Iris machines from EuroBraille do not have APM or ACPI support
  404. to shut themselves down properly. A special I/O sequence is
  405. needed to do so, which is what this module does at
  406. kernel shutdown.
  407. This is only for Iris machines from EuroBraille.
  408. If unused, say N.
  409. config SCHED_OMIT_FRAME_POINTER
  410. def_bool y
  411. prompt "Single-depth WCHAN output"
  412. depends on X86
  413. ---help---
  414. Calculate simpler /proc/<PID>/wchan values. If this option
  415. is disabled then wchan values will recurse back to the
  416. caller function. This provides more accurate wchan values,
  417. at the expense of slightly more scheduling overhead.
  418. If in doubt, say "Y".
  419. menuconfig PARAVIRT_GUEST
  420. bool "Paravirtualized guest support"
  421. ---help---
  422. Say Y here to get to see options related to running Linux under
  423. various hypervisors. This option alone does not add any kernel code.
  424. If you say N, all options in this submenu will be skipped and disabled.
  425. if PARAVIRT_GUEST
  426. source "arch/x86/xen/Kconfig"
  427. config KVM_CLOCK
  428. bool "KVM paravirtualized clock"
  429. select PARAVIRT
  430. select PARAVIRT_CLOCK
  431. ---help---
  432. Turning on this option will allow you to run a paravirtualized clock
  433. when running over the KVM hypervisor. Instead of relying on a PIT
  434. (or probably other) emulation by the underlying device model, the host
  435. provides the guest with timing infrastructure such as time of day, and
  436. system time
  437. config KVM_GUEST
  438. bool "KVM Guest support"
  439. select PARAVIRT
  440. ---help---
  441. This option enables various optimizations for running under the KVM
  442. hypervisor.
  443. source "arch/x86/lguest/Kconfig"
  444. config PARAVIRT
  445. bool "Enable paravirtualization code"
  446. ---help---
  447. This changes the kernel so it can modify itself when it is run
  448. under a hypervisor, potentially improving performance significantly
  449. over full virtualization. However, when run without a hypervisor
  450. the kernel is theoretically slower and slightly larger.
  451. config PARAVIRT_SPINLOCKS
  452. bool "Paravirtualization layer for spinlocks"
  453. depends on PARAVIRT && SMP && EXPERIMENTAL
  454. ---help---
  455. Paravirtualized spinlocks allow a pvops backend to replace the
  456. spinlock implementation with something virtualization-friendly
  457. (for example, block the virtual CPU rather than spinning).
  458. Unfortunately the downside is an up to 5% performance hit on
  459. native kernels, with various workloads.
  460. If you are unsure how to answer this question, answer N.
  461. config PARAVIRT_CLOCK
  462. bool
  463. endif
  464. config PARAVIRT_DEBUG
  465. bool "paravirt-ops debugging"
  466. depends on PARAVIRT && DEBUG_KERNEL
  467. ---help---
  468. Enable to debug paravirt_ops internals. Specifically, BUG if
  469. a paravirt_op is missing when it is called.
  470. config NO_BOOTMEM
  471. def_bool y
  472. config MEMTEST
  473. bool "Memtest"
  474. ---help---
  475. This option adds a kernel parameter 'memtest', which allows memtest
  476. to be set.
  477. memtest=0, mean disabled; -- default
  478. memtest=1, mean do 1 test pattern;
  479. ...
  480. memtest=4, mean do 4 test patterns.
  481. If you are unsure how to answer this question, answer N.
  482. config X86_SUMMIT_NUMA
  483. def_bool y
  484. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  485. config X86_CYCLONE_TIMER
  486. def_bool y
  487. depends on X86_32_NON_STANDARD
  488. source "arch/x86/Kconfig.cpu"
  489. config HPET_TIMER
  490. def_bool X86_64
  491. prompt "HPET Timer Support" if X86_32
  492. ---help---
  493. Use the IA-PC HPET (High Precision Event Timer) to manage
  494. time in preference to the PIT and RTC, if a HPET is
  495. present.
  496. HPET is the next generation timer replacing legacy 8254s.
  497. The HPET provides a stable time base on SMP
  498. systems, unlike the TSC, but it is more expensive to access,
  499. as it is off-chip. You can find the HPET spec at
  500. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  501. You can safely choose Y here. However, HPET will only be
  502. activated if the platform and the BIOS support this feature.
  503. Otherwise the 8254 will be used for timing services.
  504. Choose N to continue using the legacy 8254 timer.
  505. config HPET_EMULATE_RTC
  506. def_bool y
  507. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  508. config APB_TIMER
  509. def_bool y if MRST
  510. prompt "Langwell APB Timer Support" if X86_MRST
  511. help
  512. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  513. The APBT provides a stable time base on SMP
  514. systems, unlike the TSC, but it is more expensive to access,
  515. as it is off-chip. APB timers are always running regardless of CPU
  516. C states, they are used as per CPU clockevent device when possible.
  517. # Mark as expert because too many people got it wrong.
  518. # The code disables itself when not needed.
  519. config DMI
  520. default y
  521. bool "Enable DMI scanning" if EXPERT
  522. ---help---
  523. Enabled scanning of DMI to identify machine quirks. Say Y
  524. here unless you have verified that your setup is not
  525. affected by entries in the DMI blacklist. Required by PNP
  526. BIOS code.
  527. config GART_IOMMU
  528. bool "GART IOMMU support" if EXPERT
  529. default y
  530. select SWIOTLB
  531. depends on X86_64 && PCI && AMD_NB
  532. ---help---
  533. Support for full DMA access of devices with 32bit memory access only
  534. on systems with more than 3GB. This is usually needed for USB,
  535. sound, many IDE/SATA chipsets and some other devices.
  536. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  537. based hardware IOMMU and a software bounce buffer based IOMMU used
  538. on Intel systems and as fallback.
  539. The code is only active when needed (enough memory and limited
  540. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  541. too.
  542. config CALGARY_IOMMU
  543. bool "IBM Calgary IOMMU support"
  544. select SWIOTLB
  545. depends on X86_64 && PCI && EXPERIMENTAL
  546. ---help---
  547. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  548. systems. Needed to run systems with more than 3GB of memory
  549. properly with 32-bit PCI devices that do not support DAC
  550. (Double Address Cycle). Calgary also supports bus level
  551. isolation, where all DMAs pass through the IOMMU. This
  552. prevents them from going anywhere except their intended
  553. destination. This catches hard-to-find kernel bugs and
  554. mis-behaving drivers and devices that do not use the DMA-API
  555. properly to set up their DMA buffers. The IOMMU can be
  556. turned off at boot time with the iommu=off parameter.
  557. Normally the kernel will make the right choice by itself.
  558. If unsure, say Y.
  559. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  560. def_bool y
  561. prompt "Should Calgary be enabled by default?"
  562. depends on CALGARY_IOMMU
  563. ---help---
  564. Should Calgary be enabled by default? if you choose 'y', Calgary
  565. will be used (if it exists). If you choose 'n', Calgary will not be
  566. used even if it exists. If you choose 'n' and would like to use
  567. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  568. If unsure, say Y.
  569. config AMD_IOMMU
  570. bool "AMD IOMMU support"
  571. select SWIOTLB
  572. select PCI_MSI
  573. select PCI_IOV
  574. depends on X86_64 && PCI && ACPI
  575. ---help---
  576. With this option you can enable support for AMD IOMMU hardware in
  577. your system. An IOMMU is a hardware component which provides
  578. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  579. can isolate the the DMA memory of different devices and protect the
  580. system from misbehaving device drivers or hardware.
  581. You can find out if your system has an AMD IOMMU if you look into
  582. your BIOS for an option to enable it or if you have an IVRS ACPI
  583. table.
  584. config AMD_IOMMU_STATS
  585. bool "Export AMD IOMMU statistics to debugfs"
  586. depends on AMD_IOMMU
  587. select DEBUG_FS
  588. ---help---
  589. This option enables code in the AMD IOMMU driver to collect various
  590. statistics about whats happening in the driver and exports that
  591. information to userspace via debugfs.
  592. If unsure, say N.
  593. # need this always selected by IOMMU for the VIA workaround
  594. config SWIOTLB
  595. def_bool y if X86_64
  596. ---help---
  597. Support for software bounce buffers used on x86-64 systems
  598. which don't have a hardware IOMMU (e.g. the current generation
  599. of Intel's x86-64 CPUs). Using this PCI devices which can only
  600. access 32-bits of memory can be used on systems with more than
  601. 3 GB of memory. If unsure, say Y.
  602. config IOMMU_HELPER
  603. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  604. config IOMMU_API
  605. def_bool (AMD_IOMMU || DMAR)
  606. config MAXSMP
  607. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  608. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  609. select CPUMASK_OFFSTACK
  610. ---help---
  611. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  612. If unsure, say N.
  613. config NR_CPUS
  614. int "Maximum number of CPUs" if SMP && !MAXSMP
  615. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  616. range 2 512 if SMP && !MAXSMP
  617. default "1" if !SMP
  618. default "4096" if MAXSMP
  619. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  620. default "8" if SMP
  621. ---help---
  622. This allows you to specify the maximum number of CPUs which this
  623. kernel will support. The maximum supported value is 512 and the
  624. minimum value which makes sense is 2.
  625. This is purely to save memory - each supported CPU adds
  626. approximately eight kilobytes to the kernel image.
  627. config SCHED_SMT
  628. bool "SMT (Hyperthreading) scheduler support"
  629. depends on X86_HT
  630. ---help---
  631. SMT scheduler support improves the CPU scheduler's decision making
  632. when dealing with Intel Pentium 4 chips with HyperThreading at a
  633. cost of slightly increased overhead in some places. If unsure say
  634. N here.
  635. config SCHED_MC
  636. def_bool y
  637. prompt "Multi-core scheduler support"
  638. depends on X86_HT
  639. ---help---
  640. Multi-core scheduler support improves the CPU scheduler's decision
  641. making when dealing with multi-core CPU chips at a cost of slightly
  642. increased overhead in some places. If unsure say N here.
  643. config IRQ_TIME_ACCOUNTING
  644. bool "Fine granularity task level IRQ time accounting"
  645. default n
  646. ---help---
  647. Select this option to enable fine granularity task irq time
  648. accounting. This is done by reading a timestamp on each
  649. transitions between softirq and hardirq state, so there can be a
  650. small performance impact.
  651. If in doubt, say N here.
  652. source "kernel/Kconfig.preempt"
  653. config X86_UP_APIC
  654. bool "Local APIC support on uniprocessors"
  655. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  656. ---help---
  657. A local APIC (Advanced Programmable Interrupt Controller) is an
  658. integrated interrupt controller in the CPU. If you have a single-CPU
  659. system which has a processor with a local APIC, you can say Y here to
  660. enable and use it. If you say Y here even though your machine doesn't
  661. have a local APIC, then the kernel will still run with no slowdown at
  662. all. The local APIC supports CPU-generated self-interrupts (timer,
  663. performance counters), and the NMI watchdog which detects hard
  664. lockups.
  665. config X86_UP_IOAPIC
  666. bool "IO-APIC support on uniprocessors"
  667. depends on X86_UP_APIC
  668. ---help---
  669. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  670. SMP-capable replacement for PC-style interrupt controllers. Most
  671. SMP systems and many recent uniprocessor systems have one.
  672. If you have a single-CPU system with an IO-APIC, you can say Y here
  673. to use it. If you say Y here even though your machine doesn't have
  674. an IO-APIC, then the kernel will still run with no slowdown at all.
  675. config X86_LOCAL_APIC
  676. def_bool y
  677. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  678. config X86_IO_APIC
  679. def_bool y
  680. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
  681. config X86_VISWS_APIC
  682. def_bool y
  683. depends on X86_32 && X86_VISWS
  684. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  685. bool "Reroute for broken boot IRQs"
  686. depends on X86_IO_APIC
  687. ---help---
  688. This option enables a workaround that fixes a source of
  689. spurious interrupts. This is recommended when threaded
  690. interrupt handling is used on systems where the generation of
  691. superfluous "boot interrupts" cannot be disabled.
  692. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  693. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  694. kernel does during interrupt handling). On chipsets where this
  695. boot IRQ generation cannot be disabled, this workaround keeps
  696. the original IRQ line masked so that only the equivalent "boot
  697. IRQ" is delivered to the CPUs. The workaround also tells the
  698. kernel to set up the IRQ handler on the boot IRQ line. In this
  699. way only one interrupt is delivered to the kernel. Otherwise
  700. the spurious second interrupt may cause the kernel to bring
  701. down (vital) interrupt lines.
  702. Only affects "broken" chipsets. Interrupt sharing may be
  703. increased on these systems.
  704. config X86_MCE
  705. bool "Machine Check / overheating reporting"
  706. ---help---
  707. Machine Check support allows the processor to notify the
  708. kernel if it detects a problem (e.g. overheating, data corruption).
  709. The action the kernel takes depends on the severity of the problem,
  710. ranging from warning messages to halting the machine.
  711. config X86_MCE_INTEL
  712. def_bool y
  713. prompt "Intel MCE features"
  714. depends on X86_MCE && X86_LOCAL_APIC
  715. ---help---
  716. Additional support for intel specific MCE features such as
  717. the thermal monitor.
  718. config X86_MCE_AMD
  719. def_bool y
  720. prompt "AMD MCE features"
  721. depends on X86_MCE && X86_LOCAL_APIC
  722. ---help---
  723. Additional support for AMD specific MCE features such as
  724. the DRAM Error Threshold.
  725. config X86_ANCIENT_MCE
  726. bool "Support for old Pentium 5 / WinChip machine checks"
  727. depends on X86_32 && X86_MCE
  728. ---help---
  729. Include support for machine check handling on old Pentium 5 or WinChip
  730. systems. These typically need to be enabled explicitely on the command
  731. line.
  732. config X86_MCE_THRESHOLD
  733. depends on X86_MCE_AMD || X86_MCE_INTEL
  734. def_bool y
  735. config X86_MCE_INJECT
  736. depends on X86_MCE
  737. tristate "Machine check injector support"
  738. ---help---
  739. Provide support for injecting machine checks for testing purposes.
  740. If you don't know what a machine check is and you don't do kernel
  741. QA it is safe to say n.
  742. config X86_THERMAL_VECTOR
  743. def_bool y
  744. depends on X86_MCE_INTEL
  745. config VM86
  746. bool "Enable VM86 support" if EXPERT
  747. default y
  748. depends on X86_32
  749. ---help---
  750. This option is required by programs like DOSEMU to run 16-bit legacy
  751. code on X86 processors. It also may be needed by software like
  752. XFree86 to initialize some video cards via BIOS. Disabling this
  753. option saves about 6k.
  754. config TOSHIBA
  755. tristate "Toshiba Laptop support"
  756. depends on X86_32
  757. ---help---
  758. This adds a driver to safely access the System Management Mode of
  759. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  760. not work on models with a Phoenix BIOS. The System Management Mode
  761. is used to set the BIOS and power saving options on Toshiba portables.
  762. For information on utilities to make use of this driver see the
  763. Toshiba Linux utilities web site at:
  764. <http://www.buzzard.org.uk/toshiba/>.
  765. Say Y if you intend to run this kernel on a Toshiba portable.
  766. Say N otherwise.
  767. config I8K
  768. tristate "Dell laptop support"
  769. select HWMON
  770. ---help---
  771. This adds a driver to safely access the System Management Mode
  772. of the CPU on the Dell Inspiron 8000. The System Management Mode
  773. is used to read cpu temperature and cooling fan status and to
  774. control the fans on the I8K portables.
  775. This driver has been tested only on the Inspiron 8000 but it may
  776. also work with other Dell laptops. You can force loading on other
  777. models by passing the parameter `force=1' to the module. Use at
  778. your own risk.
  779. For information on utilities to make use of this driver see the
  780. I8K Linux utilities web site at:
  781. <http://people.debian.org/~dz/i8k/>
  782. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  783. Say N otherwise.
  784. config X86_REBOOTFIXUPS
  785. bool "Enable X86 board specific fixups for reboot"
  786. depends on X86_32
  787. ---help---
  788. This enables chipset and/or board specific fixups to be done
  789. in order to get reboot to work correctly. This is only needed on
  790. some combinations of hardware and BIOS. The symptom, for which
  791. this config is intended, is when reboot ends with a stalled/hung
  792. system.
  793. Currently, the only fixup is for the Geode machines using
  794. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  795. Say Y if you want to enable the fixup. Currently, it's safe to
  796. enable this option even if you don't need it.
  797. Say N otherwise.
  798. config MICROCODE
  799. tristate "/dev/cpu/microcode - microcode support"
  800. select FW_LOADER
  801. ---help---
  802. If you say Y here, you will be able to update the microcode on
  803. certain Intel and AMD processors. The Intel support is for the
  804. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  805. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  806. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  807. You will obviously need the actual microcode binary data itself
  808. which is not shipped with the Linux kernel.
  809. This option selects the general module only, you need to select
  810. at least one vendor specific module as well.
  811. To compile this driver as a module, choose M here: the
  812. module will be called microcode.
  813. config MICROCODE_INTEL
  814. bool "Intel microcode patch loading support"
  815. depends on MICROCODE
  816. default MICROCODE
  817. select FW_LOADER
  818. ---help---
  819. This options enables microcode patch loading support for Intel
  820. processors.
  821. For latest news and information on obtaining all the required
  822. Intel ingredients for this driver, check:
  823. <http://www.urbanmyth.org/microcode/>.
  824. config MICROCODE_AMD
  825. bool "AMD microcode patch loading support"
  826. depends on MICROCODE
  827. select FW_LOADER
  828. ---help---
  829. If you select this option, microcode patch loading support for AMD
  830. processors will be enabled.
  831. config MICROCODE_OLD_INTERFACE
  832. def_bool y
  833. depends on MICROCODE
  834. config X86_MSR
  835. tristate "/dev/cpu/*/msr - Model-specific register support"
  836. ---help---
  837. This device gives privileged processes access to the x86
  838. Model-Specific Registers (MSRs). It is a character device with
  839. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  840. MSR accesses are directed to a specific CPU on multi-processor
  841. systems.
  842. config X86_CPUID
  843. tristate "/dev/cpu/*/cpuid - CPU information support"
  844. ---help---
  845. This device gives processes access to the x86 CPUID instruction to
  846. be executed on a specific processor. It is a character device
  847. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  848. /dev/cpu/31/cpuid.
  849. choice
  850. prompt "High Memory Support"
  851. default HIGHMEM64G if X86_NUMAQ
  852. default HIGHMEM4G
  853. depends on X86_32
  854. config NOHIGHMEM
  855. bool "off"
  856. depends on !X86_NUMAQ
  857. ---help---
  858. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  859. However, the address space of 32-bit x86 processors is only 4
  860. Gigabytes large. That means that, if you have a large amount of
  861. physical memory, not all of it can be "permanently mapped" by the
  862. kernel. The physical memory that's not permanently mapped is called
  863. "high memory".
  864. If you are compiling a kernel which will never run on a machine with
  865. more than 1 Gigabyte total physical RAM, answer "off" here (default
  866. choice and suitable for most users). This will result in a "3GB/1GB"
  867. split: 3GB are mapped so that each process sees a 3GB virtual memory
  868. space and the remaining part of the 4GB virtual memory space is used
  869. by the kernel to permanently map as much physical memory as
  870. possible.
  871. If the machine has between 1 and 4 Gigabytes physical RAM, then
  872. answer "4GB" here.
  873. If more than 4 Gigabytes is used then answer "64GB" here. This
  874. selection turns Intel PAE (Physical Address Extension) mode on.
  875. PAE implements 3-level paging on IA32 processors. PAE is fully
  876. supported by Linux, PAE mode is implemented on all recent Intel
  877. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  878. then the kernel will not boot on CPUs that don't support PAE!
  879. The actual amount of total physical memory will either be
  880. auto detected or can be forced by using a kernel command line option
  881. such as "mem=256M". (Try "man bootparam" or see the documentation of
  882. your boot loader (lilo or loadlin) about how to pass options to the
  883. kernel at boot time.)
  884. If unsure, say "off".
  885. config HIGHMEM4G
  886. bool "4GB"
  887. depends on !X86_NUMAQ
  888. ---help---
  889. Select this if you have a 32-bit processor and between 1 and 4
  890. gigabytes of physical RAM.
  891. config HIGHMEM64G
  892. bool "64GB"
  893. depends on !M386 && !M486
  894. select X86_PAE
  895. ---help---
  896. Select this if you have a 32-bit processor and more than 4
  897. gigabytes of physical RAM.
  898. endchoice
  899. choice
  900. depends on EXPERIMENTAL
  901. prompt "Memory split" if EXPERT
  902. default VMSPLIT_3G
  903. depends on X86_32
  904. ---help---
  905. Select the desired split between kernel and user memory.
  906. If the address range available to the kernel is less than the
  907. physical memory installed, the remaining memory will be available
  908. as "high memory". Accessing high memory is a little more costly
  909. than low memory, as it needs to be mapped into the kernel first.
  910. Note that increasing the kernel address space limits the range
  911. available to user programs, making the address space there
  912. tighter. Selecting anything other than the default 3G/1G split
  913. will also likely make your kernel incompatible with binary-only
  914. kernel modules.
  915. If you are not absolutely sure what you are doing, leave this
  916. option alone!
  917. config VMSPLIT_3G
  918. bool "3G/1G user/kernel split"
  919. config VMSPLIT_3G_OPT
  920. depends on !X86_PAE
  921. bool "3G/1G user/kernel split (for full 1G low memory)"
  922. config VMSPLIT_2G
  923. bool "2G/2G user/kernel split"
  924. config VMSPLIT_2G_OPT
  925. depends on !X86_PAE
  926. bool "2G/2G user/kernel split (for full 2G low memory)"
  927. config VMSPLIT_1G
  928. bool "1G/3G user/kernel split"
  929. endchoice
  930. config PAGE_OFFSET
  931. hex
  932. default 0xB0000000 if VMSPLIT_3G_OPT
  933. default 0x80000000 if VMSPLIT_2G
  934. default 0x78000000 if VMSPLIT_2G_OPT
  935. default 0x40000000 if VMSPLIT_1G
  936. default 0xC0000000
  937. depends on X86_32
  938. config HIGHMEM
  939. def_bool y
  940. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  941. config X86_PAE
  942. bool "PAE (Physical Address Extension) Support"
  943. depends on X86_32 && !HIGHMEM4G
  944. ---help---
  945. PAE is required for NX support, and furthermore enables
  946. larger swapspace support for non-overcommit purposes. It
  947. has the cost of more pagetable lookup overhead, and also
  948. consumes more pagetable space per process.
  949. config ARCH_PHYS_ADDR_T_64BIT
  950. def_bool X86_64 || X86_PAE
  951. config ARCH_DMA_ADDR_T_64BIT
  952. def_bool X86_64 || HIGHMEM64G
  953. config DIRECT_GBPAGES
  954. bool "Enable 1GB pages for kernel pagetables" if EXPERT
  955. default y
  956. depends on X86_64
  957. ---help---
  958. Allow the kernel linear mapping to use 1GB pages on CPUs that
  959. support it. This can improve the kernel's performance a tiny bit by
  960. reducing TLB pressure. If in doubt, say "Y".
  961. # Common NUMA Features
  962. config NUMA
  963. bool "Numa Memory Allocation and Scheduler Support"
  964. depends on SMP
  965. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  966. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  967. ---help---
  968. Enable NUMA (Non Uniform Memory Access) support.
  969. The kernel will try to allocate memory used by a CPU on the
  970. local memory controller of the CPU and add some more
  971. NUMA awareness to the kernel.
  972. For 64-bit this is recommended if the system is Intel Core i7
  973. (or later), AMD Opteron, or EM64T NUMA.
  974. For 32-bit this is only needed on (rare) 32-bit-only platforms
  975. that support NUMA topologies, such as NUMAQ / Summit, or if you
  976. boot a 32-bit kernel on a 64-bit NUMA platform.
  977. Otherwise, you should say N.
  978. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  979. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  980. config AMD_NUMA
  981. def_bool y
  982. prompt "Old style AMD Opteron NUMA detection"
  983. depends on X86_64 && NUMA && PCI
  984. ---help---
  985. Enable AMD NUMA node topology detection. You should say Y here if
  986. you have a multi processor AMD system. This uses an old method to
  987. read the NUMA configuration directly from the builtin Northbridge
  988. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  989. which also takes priority if both are compiled in.
  990. config X86_64_ACPI_NUMA
  991. def_bool y
  992. prompt "ACPI NUMA detection"
  993. depends on X86_64 && NUMA && ACPI && PCI
  994. select ACPI_NUMA
  995. ---help---
  996. Enable ACPI SRAT based node topology detection.
  997. # Some NUMA nodes have memory ranges that span
  998. # other nodes. Even though a pfn is valid and
  999. # between a node's start and end pfns, it may not
  1000. # reside on that node. See memmap_init_zone()
  1001. # for details.
  1002. config NODES_SPAN_OTHER_NODES
  1003. def_bool y
  1004. depends on X86_64_ACPI_NUMA
  1005. config NUMA_EMU
  1006. bool "NUMA emulation"
  1007. depends on NUMA
  1008. ---help---
  1009. Enable NUMA emulation. A flat machine will be split
  1010. into virtual nodes when booted with "numa=fake=N", where N is the
  1011. number of nodes. This is only useful for debugging.
  1012. config NODES_SHIFT
  1013. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1014. range 1 10
  1015. default "10" if MAXSMP
  1016. default "6" if X86_64
  1017. default "4" if X86_NUMAQ
  1018. default "3"
  1019. depends on NEED_MULTIPLE_NODES
  1020. ---help---
  1021. Specify the maximum number of NUMA Nodes available on the target
  1022. system. Increases memory reserved to accommodate various tables.
  1023. config HAVE_ARCH_BOOTMEM
  1024. def_bool y
  1025. depends on X86_32 && NUMA
  1026. config HAVE_ARCH_ALLOC_REMAP
  1027. def_bool y
  1028. depends on X86_32 && NUMA
  1029. config ARCH_HAVE_MEMORY_PRESENT
  1030. def_bool y
  1031. depends on X86_32 && DISCONTIGMEM
  1032. config NEED_NODE_MEMMAP_SIZE
  1033. def_bool y
  1034. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1035. config ARCH_FLATMEM_ENABLE
  1036. def_bool y
  1037. depends on X86_32 && !NUMA
  1038. config ARCH_DISCONTIGMEM_ENABLE
  1039. def_bool y
  1040. depends on NUMA && X86_32
  1041. config ARCH_DISCONTIGMEM_DEFAULT
  1042. def_bool y
  1043. depends on NUMA && X86_32
  1044. config ARCH_SPARSEMEM_ENABLE
  1045. def_bool y
  1046. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1047. select SPARSEMEM_STATIC if X86_32
  1048. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1049. config ARCH_SPARSEMEM_DEFAULT
  1050. def_bool y
  1051. depends on X86_64
  1052. config ARCH_SELECT_MEMORY_MODEL
  1053. def_bool y
  1054. depends on ARCH_SPARSEMEM_ENABLE
  1055. config ARCH_MEMORY_PROBE
  1056. def_bool X86_64
  1057. depends on MEMORY_HOTPLUG
  1058. config ARCH_PROC_KCORE_TEXT
  1059. def_bool y
  1060. depends on X86_64 && PROC_KCORE
  1061. config ILLEGAL_POINTER_VALUE
  1062. hex
  1063. default 0 if X86_32
  1064. default 0xdead000000000000 if X86_64
  1065. source "mm/Kconfig"
  1066. config HIGHPTE
  1067. bool "Allocate 3rd-level pagetables from highmem"
  1068. depends on HIGHMEM
  1069. ---help---
  1070. The VM uses one page table entry for each page of physical memory.
  1071. For systems with a lot of RAM, this can be wasteful of precious
  1072. low memory. Setting this option will put user-space page table
  1073. entries in high memory.
  1074. config X86_CHECK_BIOS_CORRUPTION
  1075. bool "Check for low memory corruption"
  1076. ---help---
  1077. Periodically check for memory corruption in low memory, which
  1078. is suspected to be caused by BIOS. Even when enabled in the
  1079. configuration, it is disabled at runtime. Enable it by
  1080. setting "memory_corruption_check=1" on the kernel command
  1081. line. By default it scans the low 64k of memory every 60
  1082. seconds; see the memory_corruption_check_size and
  1083. memory_corruption_check_period parameters in
  1084. Documentation/kernel-parameters.txt to adjust this.
  1085. When enabled with the default parameters, this option has
  1086. almost no overhead, as it reserves a relatively small amount
  1087. of memory and scans it infrequently. It both detects corruption
  1088. and prevents it from affecting the running system.
  1089. It is, however, intended as a diagnostic tool; if repeatable
  1090. BIOS-originated corruption always affects the same memory,
  1091. you can use memmap= to prevent the kernel from using that
  1092. memory.
  1093. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1094. bool "Set the default setting of memory_corruption_check"
  1095. depends on X86_CHECK_BIOS_CORRUPTION
  1096. default y
  1097. ---help---
  1098. Set whether the default state of memory_corruption_check is
  1099. on or off.
  1100. config X86_RESERVE_LOW
  1101. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1102. default 64
  1103. range 4 640
  1104. ---help---
  1105. Specify the amount of low memory to reserve for the BIOS.
  1106. The first page contains BIOS data structures that the kernel
  1107. must not use, so that page must always be reserved.
  1108. By default we reserve the first 64K of physical RAM, as a
  1109. number of BIOSes are known to corrupt that memory range
  1110. during events such as suspend/resume or monitor cable
  1111. insertion, so it must not be used by the kernel.
  1112. You can set this to 4 if you are absolutely sure that you
  1113. trust the BIOS to get all its memory reservations and usages
  1114. right. If you know your BIOS have problems beyond the
  1115. default 64K area, you can set this to 640 to avoid using the
  1116. entire low memory range.
  1117. If you have doubts about the BIOS (e.g. suspend/resume does
  1118. not work or there's kernel crashes after certain hardware
  1119. hotplug events) then you might want to enable
  1120. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1121. typical corruption patterns.
  1122. Leave this to the default value of 64 if you are unsure.
  1123. config MATH_EMULATION
  1124. bool
  1125. prompt "Math emulation" if X86_32
  1126. ---help---
  1127. Linux can emulate a math coprocessor (used for floating point
  1128. operations) if you don't have one. 486DX and Pentium processors have
  1129. a math coprocessor built in, 486SX and 386 do not, unless you added
  1130. a 487DX or 387, respectively. (The messages during boot time can
  1131. give you some hints here ["man dmesg"].) Everyone needs either a
  1132. coprocessor or this emulation.
  1133. If you don't have a math coprocessor, you need to say Y here; if you
  1134. say Y here even though you have a coprocessor, the coprocessor will
  1135. be used nevertheless. (This behavior can be changed with the kernel
  1136. command line option "no387", which comes handy if your coprocessor
  1137. is broken. Try "man bootparam" or see the documentation of your boot
  1138. loader (lilo or loadlin) about how to pass options to the kernel at
  1139. boot time.) This means that it is a good idea to say Y here if you
  1140. intend to use this kernel on different machines.
  1141. More information about the internals of the Linux math coprocessor
  1142. emulation can be found in <file:arch/x86/math-emu/README>.
  1143. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1144. kernel, it won't hurt.
  1145. config MTRR
  1146. def_bool y
  1147. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1148. ---help---
  1149. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1150. the Memory Type Range Registers (MTRRs) may be used to control
  1151. processor access to memory ranges. This is most useful if you have
  1152. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1153. allows bus write transfers to be combined into a larger transfer
  1154. before bursting over the PCI/AGP bus. This can increase performance
  1155. of image write operations 2.5 times or more. Saying Y here creates a
  1156. /proc/mtrr file which may be used to manipulate your processor's
  1157. MTRRs. Typically the X server should use this.
  1158. This code has a reasonably generic interface so that similar
  1159. control registers on other processors can be easily supported
  1160. as well:
  1161. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1162. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1163. these, the ARRs are used to emulate the MTRRs.
  1164. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1165. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1166. write-combining. All of these processors are supported by this code
  1167. and it makes sense to say Y here if you have one of them.
  1168. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1169. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1170. can lead to all sorts of problems, so it's good to say Y here.
  1171. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1172. just add about 9 KB to your kernel.
  1173. See <file:Documentation/x86/mtrr.txt> for more information.
  1174. config MTRR_SANITIZER
  1175. def_bool y
  1176. prompt "MTRR cleanup support"
  1177. depends on MTRR
  1178. ---help---
  1179. Convert MTRR layout from continuous to discrete, so X drivers can
  1180. add writeback entries.
  1181. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1182. The largest mtrr entry size for a continuous block can be set with
  1183. mtrr_chunk_size.
  1184. If unsure, say Y.
  1185. config MTRR_SANITIZER_ENABLE_DEFAULT
  1186. int "MTRR cleanup enable value (0-1)"
  1187. range 0 1
  1188. default "0"
  1189. depends on MTRR_SANITIZER
  1190. ---help---
  1191. Enable mtrr cleanup default value
  1192. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1193. int "MTRR cleanup spare reg num (0-7)"
  1194. range 0 7
  1195. default "1"
  1196. depends on MTRR_SANITIZER
  1197. ---help---
  1198. mtrr cleanup spare entries default, it can be changed via
  1199. mtrr_spare_reg_nr=N on the kernel command line.
  1200. config X86_PAT
  1201. def_bool y
  1202. prompt "x86 PAT support" if EXPERT
  1203. depends on MTRR
  1204. ---help---
  1205. Use PAT attributes to setup page level cache control.
  1206. PATs are the modern equivalents of MTRRs and are much more
  1207. flexible than MTRRs.
  1208. Say N here if you see bootup problems (boot crash, boot hang,
  1209. spontaneous reboots) or a non-working video driver.
  1210. If unsure, say Y.
  1211. config ARCH_USES_PG_UNCACHED
  1212. def_bool y
  1213. depends on X86_PAT
  1214. config EFI
  1215. bool "EFI runtime service support"
  1216. depends on ACPI
  1217. ---help---
  1218. This enables the kernel to use EFI runtime services that are
  1219. available (such as the EFI variable services).
  1220. This option is only useful on systems that have EFI firmware.
  1221. In addition, you should use the latest ELILO loader available
  1222. at <http://elilo.sourceforge.net> in order to take advantage
  1223. of EFI runtime services. However, even with this option, the
  1224. resultant kernel should continue to boot on existing non-EFI
  1225. platforms.
  1226. config SECCOMP
  1227. def_bool y
  1228. prompt "Enable seccomp to safely compute untrusted bytecode"
  1229. ---help---
  1230. This kernel feature is useful for number crunching applications
  1231. that may need to compute untrusted bytecode during their
  1232. execution. By using pipes or other transports made available to
  1233. the process as file descriptors supporting the read/write
  1234. syscalls, it's possible to isolate those applications in
  1235. their own address space using seccomp. Once seccomp is
  1236. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1237. and the task is only allowed to execute a few safe syscalls
  1238. defined by each seccomp mode.
  1239. If unsure, say Y. Only embedded should say N here.
  1240. config CC_STACKPROTECTOR
  1241. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1242. ---help---
  1243. This option turns on the -fstack-protector GCC feature. This
  1244. feature puts, at the beginning of functions, a canary value on
  1245. the stack just before the return address, and validates
  1246. the value just before actually returning. Stack based buffer
  1247. overflows (that need to overwrite this return address) now also
  1248. overwrite the canary, which gets detected and the attack is then
  1249. neutralized via a kernel panic.
  1250. This feature requires gcc version 4.2 or above, or a distribution
  1251. gcc with the feature backported. Older versions are automatically
  1252. detected and for those versions, this configuration option is
  1253. ignored. (and a warning is printed during bootup)
  1254. source kernel/Kconfig.hz
  1255. config KEXEC
  1256. bool "kexec system call"
  1257. ---help---
  1258. kexec is a system call that implements the ability to shutdown your
  1259. current kernel, and to start another kernel. It is like a reboot
  1260. but it is independent of the system firmware. And like a reboot
  1261. you can start any kernel with it, not just Linux.
  1262. The name comes from the similarity to the exec system call.
  1263. It is an ongoing process to be certain the hardware in a machine
  1264. is properly shutdown, so do not be surprised if this code does not
  1265. initially work for you. It may help to enable device hotplugging
  1266. support. As of this writing the exact hardware interface is
  1267. strongly in flux, so no good recommendation can be made.
  1268. config CRASH_DUMP
  1269. bool "kernel crash dumps"
  1270. depends on X86_64 || (X86_32 && HIGHMEM)
  1271. ---help---
  1272. Generate crash dump after being started by kexec.
  1273. This should be normally only set in special crash dump kernels
  1274. which are loaded in the main kernel with kexec-tools into
  1275. a specially reserved region and then later executed after
  1276. a crash by kdump/kexec. The crash dump kernel must be compiled
  1277. to a memory address not used by the main kernel or BIOS using
  1278. PHYSICAL_START, or it must be built as a relocatable image
  1279. (CONFIG_RELOCATABLE=y).
  1280. For more details see Documentation/kdump/kdump.txt
  1281. config KEXEC_JUMP
  1282. bool "kexec jump (EXPERIMENTAL)"
  1283. depends on EXPERIMENTAL
  1284. depends on KEXEC && HIBERNATION
  1285. ---help---
  1286. Jump between original kernel and kexeced kernel and invoke
  1287. code in physical address mode via KEXEC
  1288. config PHYSICAL_START
  1289. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1290. default "0x1000000"
  1291. ---help---
  1292. This gives the physical address where the kernel is loaded.
  1293. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1294. bzImage will decompress itself to above physical address and
  1295. run from there. Otherwise, bzImage will run from the address where
  1296. it has been loaded by the boot loader and will ignore above physical
  1297. address.
  1298. In normal kdump cases one does not have to set/change this option
  1299. as now bzImage can be compiled as a completely relocatable image
  1300. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1301. address. This option is mainly useful for the folks who don't want
  1302. to use a bzImage for capturing the crash dump and want to use a
  1303. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1304. to be specifically compiled to run from a specific memory area
  1305. (normally a reserved region) and this option comes handy.
  1306. So if you are using bzImage for capturing the crash dump,
  1307. leave the value here unchanged to 0x1000000 and set
  1308. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1309. for capturing the crash dump change this value to start of
  1310. the reserved region. In other words, it can be set based on
  1311. the "X" value as specified in the "crashkernel=YM@XM"
  1312. command line boot parameter passed to the panic-ed
  1313. kernel. Please take a look at Documentation/kdump/kdump.txt
  1314. for more details about crash dumps.
  1315. Usage of bzImage for capturing the crash dump is recommended as
  1316. one does not have to build two kernels. Same kernel can be used
  1317. as production kernel and capture kernel. Above option should have
  1318. gone away after relocatable bzImage support is introduced. But it
  1319. is present because there are users out there who continue to use
  1320. vmlinux for dump capture. This option should go away down the
  1321. line.
  1322. Don't change this unless you know what you are doing.
  1323. config RELOCATABLE
  1324. bool "Build a relocatable kernel"
  1325. default y
  1326. ---help---
  1327. This builds a kernel image that retains relocation information
  1328. so it can be loaded someplace besides the default 1MB.
  1329. The relocations tend to make the kernel binary about 10% larger,
  1330. but are discarded at runtime.
  1331. One use is for the kexec on panic case where the recovery kernel
  1332. must live at a different physical address than the primary
  1333. kernel.
  1334. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1335. it has been loaded at and the compile time physical address
  1336. (CONFIG_PHYSICAL_START) is ignored.
  1337. # Relocation on x86-32 needs some additional build support
  1338. config X86_NEED_RELOCS
  1339. def_bool y
  1340. depends on X86_32 && RELOCATABLE
  1341. config PHYSICAL_ALIGN
  1342. hex "Alignment value to which kernel should be aligned" if X86_32
  1343. default "0x1000000"
  1344. range 0x2000 0x1000000
  1345. ---help---
  1346. This value puts the alignment restrictions on physical address
  1347. where kernel is loaded and run from. Kernel is compiled for an
  1348. address which meets above alignment restriction.
  1349. If bootloader loads the kernel at a non-aligned address and
  1350. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1351. address aligned to above value and run from there.
  1352. If bootloader loads the kernel at a non-aligned address and
  1353. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1354. load address and decompress itself to the address it has been
  1355. compiled for and run from there. The address for which kernel is
  1356. compiled already meets above alignment restrictions. Hence the
  1357. end result is that kernel runs from a physical address meeting
  1358. above alignment restrictions.
  1359. Don't change this unless you know what you are doing.
  1360. config HOTPLUG_CPU
  1361. bool "Support for hot-pluggable CPUs"
  1362. depends on SMP && HOTPLUG
  1363. ---help---
  1364. Say Y here to allow turning CPUs off and on. CPUs can be
  1365. controlled through /sys/devices/system/cpu.
  1366. ( Note: power management support will enable this option
  1367. automatically on SMP systems. )
  1368. Say N if you want to disable CPU hotplug.
  1369. config COMPAT_VDSO
  1370. def_bool y
  1371. prompt "Compat VDSO support"
  1372. depends on X86_32 || IA32_EMULATION
  1373. ---help---
  1374. Map the 32-bit VDSO to the predictable old-style address too.
  1375. Say N here if you are running a sufficiently recent glibc
  1376. version (2.3.3 or later), to remove the high-mapped
  1377. VDSO mapping and to exclusively use the randomized VDSO.
  1378. If unsure, say Y.
  1379. config CMDLINE_BOOL
  1380. bool "Built-in kernel command line"
  1381. ---help---
  1382. Allow for specifying boot arguments to the kernel at
  1383. build time. On some systems (e.g. embedded ones), it is
  1384. necessary or convenient to provide some or all of the
  1385. kernel boot arguments with the kernel itself (that is,
  1386. to not rely on the boot loader to provide them.)
  1387. To compile command line arguments into the kernel,
  1388. set this option to 'Y', then fill in the
  1389. the boot arguments in CONFIG_CMDLINE.
  1390. Systems with fully functional boot loaders (i.e. non-embedded)
  1391. should leave this option set to 'N'.
  1392. config CMDLINE
  1393. string "Built-in kernel command string"
  1394. depends on CMDLINE_BOOL
  1395. default ""
  1396. ---help---
  1397. Enter arguments here that should be compiled into the kernel
  1398. image and used at boot time. If the boot loader provides a
  1399. command line at boot time, it is appended to this string to
  1400. form the full kernel command line, when the system boots.
  1401. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1402. change this behavior.
  1403. In most cases, the command line (whether built-in or provided
  1404. by the boot loader) should specify the device for the root
  1405. file system.
  1406. config CMDLINE_OVERRIDE
  1407. bool "Built-in command line overrides boot loader arguments"
  1408. depends on CMDLINE_BOOL
  1409. ---help---
  1410. Set this option to 'Y' to have the kernel ignore the boot loader
  1411. command line, and use ONLY the built-in command line.
  1412. This is used to work around broken boot loaders. This should
  1413. be set to 'N' under normal conditions.
  1414. endmenu
  1415. config ARCH_ENABLE_MEMORY_HOTPLUG
  1416. def_bool y
  1417. depends on X86_64 || (X86_32 && HIGHMEM)
  1418. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1419. def_bool y
  1420. depends on MEMORY_HOTPLUG
  1421. config USE_PERCPU_NUMA_NODE_ID
  1422. def_bool y
  1423. depends on NUMA
  1424. menu "Power management and ACPI options"
  1425. config ARCH_HIBERNATION_HEADER
  1426. def_bool y
  1427. depends on X86_64 && HIBERNATION
  1428. source "kernel/power/Kconfig"
  1429. source "drivers/acpi/Kconfig"
  1430. source "drivers/sfi/Kconfig"
  1431. config X86_APM_BOOT
  1432. def_bool y
  1433. depends on APM || APM_MODULE
  1434. menuconfig APM
  1435. tristate "APM (Advanced Power Management) BIOS support"
  1436. depends on X86_32 && PM_SLEEP
  1437. ---help---
  1438. APM is a BIOS specification for saving power using several different
  1439. techniques. This is mostly useful for battery powered laptops with
  1440. APM compliant BIOSes. If you say Y here, the system time will be
  1441. reset after a RESUME operation, the /proc/apm device will provide
  1442. battery status information, and user-space programs will receive
  1443. notification of APM "events" (e.g. battery status change).
  1444. If you select "Y" here, you can disable actual use of the APM
  1445. BIOS by passing the "apm=off" option to the kernel at boot time.
  1446. Note that the APM support is almost completely disabled for
  1447. machines with more than one CPU.
  1448. In order to use APM, you will need supporting software. For location
  1449. and more information, read <file:Documentation/power/pm.txt> and the
  1450. Battery Powered Linux mini-HOWTO, available from
  1451. <http://www.tldp.org/docs.html#howto>.
  1452. This driver does not spin down disk drives (see the hdparm(8)
  1453. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1454. VESA-compliant "green" monitors.
  1455. This driver does not support the TI 4000M TravelMate and the ACER
  1456. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1457. desktop machines also don't have compliant BIOSes, and this driver
  1458. may cause those machines to panic during the boot phase.
  1459. Generally, if you don't have a battery in your machine, there isn't
  1460. much point in using this driver and you should say N. If you get
  1461. random kernel OOPSes or reboots that don't seem to be related to
  1462. anything, try disabling/enabling this option (or disabling/enabling
  1463. APM in your BIOS).
  1464. Some other things you should try when experiencing seemingly random,
  1465. "weird" problems:
  1466. 1) make sure that you have enough swap space and that it is
  1467. enabled.
  1468. 2) pass the "no-hlt" option to the kernel
  1469. 3) switch on floating point emulation in the kernel and pass
  1470. the "no387" option to the kernel
  1471. 4) pass the "floppy=nodma" option to the kernel
  1472. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1473. all but the first 4 MB of RAM)
  1474. 6) make sure that the CPU is not over clocked.
  1475. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1476. 8) disable the cache from your BIOS settings
  1477. 9) install a fan for the video card or exchange video RAM
  1478. 10) install a better fan for the CPU
  1479. 11) exchange RAM chips
  1480. 12) exchange the motherboard.
  1481. To compile this driver as a module, choose M here: the
  1482. module will be called apm.
  1483. if APM
  1484. config APM_IGNORE_USER_SUSPEND
  1485. bool "Ignore USER SUSPEND"
  1486. ---help---
  1487. This option will ignore USER SUSPEND requests. On machines with a
  1488. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1489. series notebooks, it is necessary to say Y because of a BIOS bug.
  1490. config APM_DO_ENABLE
  1491. bool "Enable PM at boot time"
  1492. ---help---
  1493. Enable APM features at boot time. From page 36 of the APM BIOS
  1494. specification: "When disabled, the APM BIOS does not automatically
  1495. power manage devices, enter the Standby State, enter the Suspend
  1496. State, or take power saving steps in response to CPU Idle calls."
  1497. This driver will make CPU Idle calls when Linux is idle (unless this
  1498. feature is turned off -- see "Do CPU IDLE calls", below). This
  1499. should always save battery power, but more complicated APM features
  1500. will be dependent on your BIOS implementation. You may need to turn
  1501. this option off if your computer hangs at boot time when using APM
  1502. support, or if it beeps continuously instead of suspending. Turn
  1503. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1504. T400CDT. This is off by default since most machines do fine without
  1505. this feature.
  1506. config APM_CPU_IDLE
  1507. bool "Make CPU Idle calls when idle"
  1508. ---help---
  1509. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1510. On some machines, this can activate improved power savings, such as
  1511. a slowed CPU clock rate, when the machine is idle. These idle calls
  1512. are made after the idle loop has run for some length of time (e.g.,
  1513. 333 mS). On some machines, this will cause a hang at boot time or
  1514. whenever the CPU becomes idle. (On machines with more than one CPU,
  1515. this option does nothing.)
  1516. config APM_DISPLAY_BLANK
  1517. bool "Enable console blanking using APM"
  1518. ---help---
  1519. Enable console blanking using the APM. Some laptops can use this to
  1520. turn off the LCD backlight when the screen blanker of the Linux
  1521. virtual console blanks the screen. Note that this is only used by
  1522. the virtual console screen blanker, and won't turn off the backlight
  1523. when using the X Window system. This also doesn't have anything to
  1524. do with your VESA-compliant power-saving monitor. Further, this
  1525. option doesn't work for all laptops -- it might not turn off your
  1526. backlight at all, or it might print a lot of errors to the console,
  1527. especially if you are using gpm.
  1528. config APM_ALLOW_INTS
  1529. bool "Allow interrupts during APM BIOS calls"
  1530. ---help---
  1531. Normally we disable external interrupts while we are making calls to
  1532. the APM BIOS as a measure to lessen the effects of a badly behaving
  1533. BIOS implementation. The BIOS should reenable interrupts if it
  1534. needs to. Unfortunately, some BIOSes do not -- especially those in
  1535. many of the newer IBM Thinkpads. If you experience hangs when you
  1536. suspend, try setting this to Y. Otherwise, say N.
  1537. endif # APM
  1538. source "drivers/cpufreq/Kconfig"
  1539. source "drivers/cpuidle/Kconfig"
  1540. source "drivers/idle/Kconfig"
  1541. endmenu
  1542. menu "Bus options (PCI etc.)"
  1543. config PCI
  1544. bool "PCI support"
  1545. default y
  1546. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1547. ---help---
  1548. Find out whether you have a PCI motherboard. PCI is the name of a
  1549. bus system, i.e. the way the CPU talks to the other stuff inside
  1550. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1551. VESA. If you have PCI, say Y, otherwise N.
  1552. choice
  1553. prompt "PCI access mode"
  1554. depends on X86_32 && PCI
  1555. default PCI_GOANY
  1556. ---help---
  1557. On PCI systems, the BIOS can be used to detect the PCI devices and
  1558. determine their configuration. However, some old PCI motherboards
  1559. have BIOS bugs and may crash if this is done. Also, some embedded
  1560. PCI-based systems don't have any BIOS at all. Linux can also try to
  1561. detect the PCI hardware directly without using the BIOS.
  1562. With this option, you can specify how Linux should detect the
  1563. PCI devices. If you choose "BIOS", the BIOS will be used,
  1564. if you choose "Direct", the BIOS won't be used, and if you
  1565. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1566. If you choose "Any", the kernel will try MMCONFIG, then the
  1567. direct access method and falls back to the BIOS if that doesn't
  1568. work. If unsure, go with the default, which is "Any".
  1569. config PCI_GOBIOS
  1570. bool "BIOS"
  1571. config PCI_GOMMCONFIG
  1572. bool "MMConfig"
  1573. config PCI_GODIRECT
  1574. bool "Direct"
  1575. config PCI_GOOLPC
  1576. bool "OLPC XO-1"
  1577. depends on OLPC
  1578. config PCI_GOANY
  1579. bool "Any"
  1580. endchoice
  1581. config PCI_BIOS
  1582. def_bool y
  1583. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1584. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1585. config PCI_DIRECT
  1586. def_bool y
  1587. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1588. config PCI_MMCONFIG
  1589. def_bool y
  1590. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1591. config PCI_OLPC
  1592. def_bool y
  1593. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1594. config PCI_XEN
  1595. def_bool y
  1596. depends on PCI && XEN
  1597. select SWIOTLB_XEN
  1598. config PCI_DOMAINS
  1599. def_bool y
  1600. depends on PCI
  1601. config PCI_MMCONFIG
  1602. bool "Support mmconfig PCI config space access"
  1603. depends on X86_64 && PCI && ACPI
  1604. config PCI_CNB20LE_QUIRK
  1605. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  1606. default n
  1607. depends on PCI && EXPERIMENTAL
  1608. help
  1609. Read the PCI windows out of the CNB20LE host bridge. This allows
  1610. PCI hotplug to work on systems with the CNB20LE chipset which do
  1611. not have ACPI.
  1612. There's no public spec for this chipset, and this functionality
  1613. is known to be incomplete.
  1614. You should say N unless you know you need this.
  1615. config DMAR
  1616. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1617. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1618. help
  1619. DMA remapping (DMAR) devices support enables independent address
  1620. translations for Direct Memory Access (DMA) from devices.
  1621. These DMA remapping devices are reported via ACPI tables
  1622. and include PCI device scope covered by these DMA
  1623. remapping devices.
  1624. config DMAR_DEFAULT_ON
  1625. def_bool y
  1626. prompt "Enable DMA Remapping Devices by default"
  1627. depends on DMAR
  1628. help
  1629. Selecting this option will enable a DMAR device at boot time if
  1630. one is found. If this option is not selected, DMAR support can
  1631. be enabled by passing intel_iommu=on to the kernel. It is
  1632. recommended you say N here while the DMAR code remains
  1633. experimental.
  1634. config DMAR_BROKEN_GFX_WA
  1635. bool "Workaround broken graphics drivers (going away soon)"
  1636. depends on DMAR && BROKEN
  1637. ---help---
  1638. Current Graphics drivers tend to use physical address
  1639. for DMA and avoid using DMA APIs. Setting this config
  1640. option permits the IOMMU driver to set a unity map for
  1641. all the OS-visible memory. Hence the driver can continue
  1642. to use physical addresses for DMA, at least until this
  1643. option is removed in the 2.6.32 kernel.
  1644. config DMAR_FLOPPY_WA
  1645. def_bool y
  1646. depends on DMAR
  1647. ---help---
  1648. Floppy disk drivers are known to bypass DMA API calls
  1649. thereby failing to work when IOMMU is enabled. This
  1650. workaround will setup a 1:1 mapping for the first
  1651. 16MiB to make floppy (an ISA device) work.
  1652. config INTR_REMAP
  1653. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1654. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1655. ---help---
  1656. Supports Interrupt remapping for IO-APIC and MSI devices.
  1657. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1658. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1659. source "drivers/pci/pcie/Kconfig"
  1660. source "drivers/pci/Kconfig"
  1661. # x86_64 have no ISA slots, but can have ISA-style DMA.
  1662. config ISA_DMA_API
  1663. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  1664. default y
  1665. help
  1666. Enables ISA-style DMA support for devices requiring such controllers.
  1667. If unsure, say Y.
  1668. if X86_32
  1669. config ISA
  1670. bool "ISA support"
  1671. ---help---
  1672. Find out whether you have ISA slots on your motherboard. ISA is the
  1673. name of a bus system, i.e. the way the CPU talks to the other stuff
  1674. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1675. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1676. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1677. config EISA
  1678. bool "EISA support"
  1679. depends on ISA
  1680. ---help---
  1681. The Extended Industry Standard Architecture (EISA) bus was
  1682. developed as an open alternative to the IBM MicroChannel bus.
  1683. The EISA bus provided some of the features of the IBM MicroChannel
  1684. bus while maintaining backward compatibility with cards made for
  1685. the older ISA bus. The EISA bus saw limited use between 1988 and
  1686. 1995 when it was made obsolete by the PCI bus.
  1687. Say Y here if you are building a kernel for an EISA-based machine.
  1688. Otherwise, say N.
  1689. source "drivers/eisa/Kconfig"
  1690. config MCA
  1691. bool "MCA support"
  1692. ---help---
  1693. MicroChannel Architecture is found in some IBM PS/2 machines and
  1694. laptops. It is a bus system similar to PCI or ISA. See
  1695. <file:Documentation/mca.txt> (and especially the web page given
  1696. there) before attempting to build an MCA bus kernel.
  1697. source "drivers/mca/Kconfig"
  1698. config SCx200
  1699. tristate "NatSemi SCx200 support"
  1700. ---help---
  1701. This provides basic support for National Semiconductor's
  1702. (now AMD's) Geode processors. The driver probes for the
  1703. PCI-IDs of several on-chip devices, so its a good dependency
  1704. for other scx200_* drivers.
  1705. If compiled as a module, the driver is named scx200.
  1706. config SCx200HR_TIMER
  1707. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1708. depends on SCx200
  1709. default y
  1710. ---help---
  1711. This driver provides a clocksource built upon the on-chip
  1712. 27MHz high-resolution timer. Its also a workaround for
  1713. NSC Geode SC-1100's buggy TSC, which loses time when the
  1714. processor goes idle (as is done by the scheduler). The
  1715. other workaround is idle=poll boot option.
  1716. config OLPC
  1717. bool "One Laptop Per Child support"
  1718. depends on !X86_PAE
  1719. select GPIOLIB
  1720. select OF
  1721. select OF_PROMTREE
  1722. ---help---
  1723. Add support for detecting the unique features of the OLPC
  1724. XO hardware.
  1725. config OLPC_XO1
  1726. tristate "OLPC XO-1 support"
  1727. depends on OLPC && MFD_CS5535
  1728. ---help---
  1729. Add support for non-essential features of the OLPC XO-1 laptop.
  1730. endif # X86_32
  1731. config AMD_NB
  1732. def_bool y
  1733. depends on CPU_SUP_AMD && PCI
  1734. source "drivers/pcmcia/Kconfig"
  1735. source "drivers/pci/hotplug/Kconfig"
  1736. config RAPIDIO
  1737. bool "RapidIO support"
  1738. depends on PCI
  1739. default n
  1740. help
  1741. If you say Y here, the kernel will include drivers and
  1742. infrastructure code to support RapidIO interconnect devices.
  1743. source "drivers/rapidio/Kconfig"
  1744. endmenu
  1745. menu "Executable file formats / Emulations"
  1746. source "fs/Kconfig.binfmt"
  1747. config IA32_EMULATION
  1748. bool "IA32 Emulation"
  1749. depends on X86_64
  1750. select COMPAT_BINFMT_ELF
  1751. ---help---
  1752. Include code to run 32-bit programs under a 64-bit kernel. You should
  1753. likely turn this on, unless you're 100% sure that you don't have any
  1754. 32-bit programs left.
  1755. config IA32_AOUT
  1756. tristate "IA32 a.out support"
  1757. depends on IA32_EMULATION
  1758. ---help---
  1759. Support old a.out binaries in the 32bit emulation.
  1760. config COMPAT
  1761. def_bool y
  1762. depends on IA32_EMULATION
  1763. config COMPAT_FOR_U64_ALIGNMENT
  1764. def_bool COMPAT
  1765. depends on X86_64
  1766. config SYSVIPC_COMPAT
  1767. def_bool y
  1768. depends on COMPAT && SYSVIPC
  1769. config KEYS_COMPAT
  1770. bool
  1771. depends on COMPAT && KEYS
  1772. default y
  1773. endmenu
  1774. config HAVE_ATOMIC_IOMAP
  1775. def_bool y
  1776. depends on X86_32
  1777. config HAVE_TEXT_POKE_SMP
  1778. bool
  1779. select STOP_MACHINE if SMP
  1780. source "net/Kconfig"
  1781. source "drivers/Kconfig"
  1782. source "drivers/firmware/Kconfig"
  1783. source "fs/Kconfig"
  1784. source "arch/x86/Kconfig.debug"
  1785. source "security/Kconfig"
  1786. source "crypto/Kconfig"
  1787. source "arch/x86/kvm/Kconfig"
  1788. source "lib/Kconfig"