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_READQ
  18. select HAVE_WRITEQ
  19. select HAVE_UNSTABLE_SCHED_CLOCK
  20. select HAVE_IDE
  21. select HAVE_OPROFILE
  22. select HAVE_PERF_EVENTS
  23. select HAVE_IRQ_WORK
  24. select HAVE_IOREMAP_PROT
  25. select HAVE_KPROBES
  26. select HAVE_MEMBLOCK
  27. select ARCH_WANT_OPTIONAL_GPIOLIB
  28. select ARCH_WANT_FRAME_POINTERS
  29. select HAVE_DMA_ATTRS
  30. select HAVE_KRETPROBES
  31. select HAVE_OPTPROBES
  32. select HAVE_FTRACE_MCOUNT_RECORD
  33. select HAVE_C_RECORDMCOUNT
  34. select HAVE_DYNAMIC_FTRACE
  35. select HAVE_FUNCTION_TRACER
  36. select HAVE_FUNCTION_GRAPH_TRACER
  37. select HAVE_FUNCTION_GRAPH_FP_TEST
  38. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  39. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  40. select HAVE_SYSCALL_TRACEPOINTS
  41. select HAVE_KVM
  42. select HAVE_ARCH_KGDB
  43. select HAVE_ARCH_TRACEHOOK
  44. select HAVE_GENERIC_DMA_COHERENT if X86_32
  45. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  46. select USER_STACKTRACE_SUPPORT
  47. select HAVE_REGS_AND_STACK_ACCESS_API
  48. select HAVE_DMA_API_DEBUG
  49. select HAVE_KERNEL_GZIP
  50. select HAVE_KERNEL_BZIP2
  51. select HAVE_KERNEL_LZMA
  52. select HAVE_KERNEL_XZ
  53. select HAVE_KERNEL_LZO
  54. select HAVE_HW_BREAKPOINT
  55. select HAVE_MIXED_BREAKPOINTS_REGS
  56. select PERF_EVENTS
  57. select HAVE_PERF_EVENTS_NMI
  58. select ANON_INODES
  59. select HAVE_ARCH_KMEMCHECK
  60. select HAVE_USER_RETURN_NOTIFIER
  61. select HAVE_ARCH_JUMP_LABEL
  62. select HAVE_TEXT_POKE_SMP
  63. select HAVE_GENERIC_HARDIRQS
  64. select HAVE_SPARSE_IRQ
  65. select GENERIC_FIND_FIRST_BIT
  66. select GENERIC_FIND_NEXT_BIT
  67. select GENERIC_IRQ_PROBE
  68. select GENERIC_PENDING_IRQ if SMP
  69. select GENERIC_IRQ_SHOW
  70. select IRQ_FORCED_THREADING
  71. select USE_GENERIC_SMP_HELPERS if SMP
  72. select HAVE_BPF_JIT if (X86_64 && NET)
  73. config INSTRUCTION_DECODER
  74. def_bool (KPROBES || PERF_EVENTS)
  75. config OUTPUT_FORMAT
  76. string
  77. default "elf32-i386" if X86_32
  78. default "elf64-x86-64" if X86_64
  79. config ARCH_DEFCONFIG
  80. string
  81. default "arch/x86/configs/i386_defconfig" if X86_32
  82. default "arch/x86/configs/x86_64_defconfig" if X86_64
  83. config GENERIC_CMOS_UPDATE
  84. def_bool y
  85. config CLOCKSOURCE_WATCHDOG
  86. def_bool y
  87. config GENERIC_CLOCKEVENTS
  88. def_bool y
  89. config GENERIC_CLOCKEVENTS_BROADCAST
  90. def_bool y
  91. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  92. config LOCKDEP_SUPPORT
  93. def_bool y
  94. config STACKTRACE_SUPPORT
  95. def_bool y
  96. config HAVE_LATENCYTOP_SUPPORT
  97. def_bool y
  98. config MMU
  99. def_bool y
  100. config ZONE_DMA
  101. bool "DMA memory allocation support" if EXPERT
  102. default y
  103. help
  104. DMA memory allocation support allows devices with less than 32-bit
  105. addressing to allocate within the first 16MB of address space.
  106. Disable if no such devices will be used.
  107. If unsure, say Y.
  108. config SBUS
  109. bool
  110. config NEED_DMA_MAP_STATE
  111. def_bool (X86_64 || DMAR || DMA_API_DEBUG)
  112. config NEED_SG_DMA_LENGTH
  113. def_bool y
  114. config GENERIC_ISA_DMA
  115. def_bool ISA_DMA_API
  116. config GENERIC_IOMAP
  117. def_bool y
  118. config GENERIC_BUG
  119. def_bool y
  120. depends on BUG
  121. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  122. config GENERIC_BUG_RELATIVE_POINTERS
  123. bool
  124. config GENERIC_HWEIGHT
  125. def_bool y
  126. config GENERIC_GPIO
  127. bool
  128. config ARCH_MAY_HAVE_PC_FDC
  129. def_bool ISA_DMA_API
  130. config RWSEM_GENERIC_SPINLOCK
  131. def_bool !X86_XADD
  132. config RWSEM_XCHGADD_ALGORITHM
  133. def_bool X86_XADD
  134. config ARCH_HAS_CPU_IDLE_WAIT
  135. def_bool y
  136. config GENERIC_CALIBRATE_DELAY
  137. def_bool y
  138. config GENERIC_TIME_VSYSCALL
  139. bool
  140. default X86_64
  141. config ARCH_HAS_CPU_RELAX
  142. def_bool y
  143. config ARCH_HAS_DEFAULT_IDLE
  144. def_bool y
  145. config ARCH_HAS_CACHE_LINE_SIZE
  146. def_bool y
  147. config HAVE_SETUP_PER_CPU_AREA
  148. def_bool y
  149. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  150. def_bool y
  151. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  152. def_bool y
  153. config HAVE_CPUMASK_OF_CPU_MAP
  154. def_bool X86_64_SMP
  155. config ARCH_HIBERNATION_POSSIBLE
  156. def_bool y
  157. config ARCH_SUSPEND_POSSIBLE
  158. def_bool y
  159. config ZONE_DMA32
  160. bool
  161. default X86_64
  162. config ARCH_POPULATES_NODE_MAP
  163. def_bool y
  164. config AUDIT_ARCH
  165. bool
  166. default X86_64
  167. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  168. def_bool y
  169. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  170. def_bool y
  171. config HAVE_INTEL_TXT
  172. def_bool y
  173. depends on EXPERIMENTAL && DMAR && ACPI
  174. config X86_32_SMP
  175. def_bool y
  176. depends on X86_32 && SMP
  177. config X86_64_SMP
  178. def_bool y
  179. depends on X86_64 && SMP
  180. config X86_HT
  181. def_bool y
  182. depends on SMP
  183. config X86_32_LAZY_GS
  184. def_bool y
  185. depends on X86_32 && !CC_STACKPROTECTOR
  186. config ARCH_HWEIGHT_CFLAGS
  187. string
  188. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  189. 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
  190. config KTIME_SCALAR
  191. def_bool X86_32
  192. config ARCH_CPU_PROBE_RELEASE
  193. def_bool y
  194. depends on HOTPLUG_CPU
  195. source "init/Kconfig"
  196. source "kernel/Kconfig.freezer"
  197. menu "Processor type and features"
  198. source "kernel/time/Kconfig"
  199. config SMP
  200. bool "Symmetric multi-processing support"
  201. ---help---
  202. This enables support for systems with more than one CPU. If you have
  203. a system with only one CPU, like most personal computers, say N. If
  204. you have a system with more than one CPU, say Y.
  205. If you say N here, the kernel will run on single and multiprocessor
  206. machines, but will use only one CPU of a multiprocessor machine. If
  207. you say Y here, the kernel will run on many, but not all,
  208. singleprocessor machines. On a singleprocessor machine, the kernel
  209. will run faster if you say N here.
  210. Note that if you say Y here and choose architecture "586" or
  211. "Pentium" under "Processor family", the kernel will not work on 486
  212. architectures. Similarly, multiprocessor kernels for the "PPro"
  213. architecture may not work on all Pentium based boards.
  214. People using multiprocessor machines who say Y here should also say
  215. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  216. Management" code will be disabled if you say Y here.
  217. See also <file:Documentation/i386/IO-APIC.txt>,
  218. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  219. <http://www.tldp.org/docs.html#howto>.
  220. If you don't know what to do here, say N.
  221. config X86_X2APIC
  222. bool "Support x2apic"
  223. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  224. ---help---
  225. This enables x2apic support on CPUs that have this feature.
  226. This allows 32-bit apic IDs (so it can support very large systems),
  227. and accesses the local apic via MSRs not via mmio.
  228. If you don't know what to do here, say N.
  229. config X86_MPPARSE
  230. bool "Enable MPS table" if ACPI
  231. default y
  232. depends on X86_LOCAL_APIC
  233. ---help---
  234. For old smp systems that do not have proper acpi support. Newer systems
  235. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  236. config X86_BIGSMP
  237. bool "Support for big SMP systems with more than 8 CPUs"
  238. depends on X86_32 && SMP
  239. ---help---
  240. This option is needed for the systems that have more than 8 CPUs
  241. if X86_32
  242. config X86_EXTENDED_PLATFORM
  243. bool "Support for extended (non-PC) x86 platforms"
  244. default y
  245. ---help---
  246. If you disable this option then the kernel will only support
  247. standard PC platforms. (which covers the vast majority of
  248. systems out there.)
  249. If you enable this option then you'll be able to select support
  250. for the following (non-PC) 32 bit x86 platforms:
  251. AMD Elan
  252. NUMAQ (IBM/Sequent)
  253. RDC R-321x SoC
  254. SGI 320/540 (Visual Workstation)
  255. Summit/EXA (IBM x440)
  256. Unisys ES7000 IA32 series
  257. Moorestown MID devices
  258. If you have one of these systems, or if you want to build a
  259. generic distribution kernel, say Y here - otherwise say N.
  260. endif
  261. if X86_64
  262. config X86_EXTENDED_PLATFORM
  263. bool "Support for extended (non-PC) x86 platforms"
  264. default y
  265. ---help---
  266. If you disable this option then the kernel will only support
  267. standard PC platforms. (which covers the vast majority of
  268. systems out there.)
  269. If you enable this option then you'll be able to select support
  270. for the following (non-PC) 64 bit x86 platforms:
  271. ScaleMP vSMP
  272. SGI Ultraviolet
  273. If you have one of these systems, or if you want to build a
  274. generic distribution kernel, say Y here - otherwise say N.
  275. endif
  276. # This is an alphabetically sorted list of 64 bit extended platforms
  277. # Please maintain the alphabetic order if and when there are additions
  278. config X86_VSMP
  279. bool "ScaleMP vSMP"
  280. select PARAVIRT_GUEST
  281. select PARAVIRT
  282. depends on X86_64 && PCI
  283. depends on X86_EXTENDED_PLATFORM
  284. ---help---
  285. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  286. supposed to run on these EM64T-based machines. Only choose this option
  287. if you have one of these machines.
  288. config X86_UV
  289. bool "SGI Ultraviolet"
  290. depends on X86_64
  291. depends on X86_EXTENDED_PLATFORM
  292. depends on NUMA
  293. depends on X86_X2APIC
  294. ---help---
  295. This option is needed in order to support SGI Ultraviolet systems.
  296. If you don't have one of these, you should say N here.
  297. # Following is an alphabetically sorted list of 32 bit extended platforms
  298. # Please maintain the alphabetic order if and when there are additions
  299. config X86_INTEL_CE
  300. bool "CE4100 TV platform"
  301. depends on PCI
  302. depends on PCI_GODIRECT
  303. depends on X86_32
  304. depends on X86_EXTENDED_PLATFORM
  305. select X86_REBOOTFIXUPS
  306. select OF
  307. select OF_EARLY_FLATTREE
  308. ---help---
  309. Select for the Intel CE media processor (CE4100) SOC.
  310. This option compiles in support for the CE4100 SOC for settop
  311. boxes and media devices.
  312. config X86_MRST
  313. bool "Moorestown MID platform"
  314. depends on PCI
  315. depends on PCI_GOANY
  316. depends on X86_32
  317. depends on X86_EXTENDED_PLATFORM
  318. depends on X86_IO_APIC
  319. select APB_TIMER
  320. select I2C
  321. select SPI
  322. select INTEL_SCU_IPC
  323. select X86_PLATFORM_DEVICES
  324. ---help---
  325. Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
  326. Internet Device(MID) platform. Moorestown consists of two chips:
  327. Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
  328. Unlike standard x86 PCs, Moorestown does not have many legacy devices
  329. nor standard legacy replacement devices/features. e.g. Moorestown does
  330. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  331. config X86_RDC321X
  332. bool "RDC R-321x SoC"
  333. depends on X86_32
  334. depends on X86_EXTENDED_PLATFORM
  335. select M486
  336. select X86_REBOOTFIXUPS
  337. ---help---
  338. This option is needed for RDC R-321x system-on-chip, also known
  339. as R-8610-(G).
  340. If you don't have one of these chips, you should say N here.
  341. config X86_32_NON_STANDARD
  342. bool "Support non-standard 32-bit SMP architectures"
  343. depends on X86_32 && SMP
  344. depends on X86_EXTENDED_PLATFORM
  345. ---help---
  346. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  347. subarchitectures. It is intended for a generic binary kernel.
  348. if you select them all, kernel will probe it one by one. and will
  349. fallback to default.
  350. # Alphabetically sorted list of Non standard 32 bit platforms
  351. config X86_NUMAQ
  352. bool "NUMAQ (IBM/Sequent)"
  353. depends on X86_32_NON_STANDARD
  354. depends on PCI
  355. select NUMA
  356. select X86_MPPARSE
  357. ---help---
  358. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  359. NUMA multiquad box. This changes the way that processors are
  360. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  361. of Flat Logical. You will need a new lynxer.elf file to flash your
  362. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  363. config X86_SUPPORTS_MEMORY_FAILURE
  364. def_bool y
  365. # MCE code calls memory_failure():
  366. depends on X86_MCE
  367. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  368. depends on !X86_NUMAQ
  369. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  370. depends on X86_64 || !SPARSEMEM
  371. select ARCH_SUPPORTS_MEMORY_FAILURE
  372. config X86_VISWS
  373. bool "SGI 320/540 (Visual Workstation)"
  374. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  375. depends on X86_32_NON_STANDARD
  376. ---help---
  377. The SGI Visual Workstation series is an IA32-based workstation
  378. based on SGI systems chips with some legacy PC hardware attached.
  379. Say Y here to create a kernel to run on the SGI 320 or 540.
  380. A kernel compiled for the Visual Workstation will run on general
  381. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  382. config X86_SUMMIT
  383. bool "Summit/EXA (IBM x440)"
  384. depends on X86_32_NON_STANDARD
  385. ---help---
  386. This option is needed for IBM systems that use the Summit/EXA chipset.
  387. In particular, it is needed for the x440.
  388. config X86_ES7000
  389. bool "Unisys ES7000 IA32 series"
  390. depends on X86_32_NON_STANDARD && X86_BIGSMP
  391. ---help---
  392. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  393. supposed to run on an IA32-based Unisys ES7000 system.
  394. config X86_32_IRIS
  395. tristate "Eurobraille/Iris poweroff module"
  396. depends on X86_32
  397. ---help---
  398. The Iris machines from EuroBraille do not have APM or ACPI support
  399. to shut themselves down properly. A special I/O sequence is
  400. needed to do so, which is what this module does at
  401. kernel shutdown.
  402. This is only for Iris machines from EuroBraille.
  403. If unused, say N.
  404. config SCHED_OMIT_FRAME_POINTER
  405. def_bool y
  406. prompt "Single-depth WCHAN output"
  407. depends on X86
  408. ---help---
  409. Calculate simpler /proc/<PID>/wchan values. If this option
  410. is disabled then wchan values will recurse back to the
  411. caller function. This provides more accurate wchan values,
  412. at the expense of slightly more scheduling overhead.
  413. If in doubt, say "Y".
  414. menuconfig PARAVIRT_GUEST
  415. bool "Paravirtualized guest support"
  416. ---help---
  417. Say Y here to get to see options related to running Linux under
  418. various hypervisors. This option alone does not add any kernel code.
  419. If you say N, all options in this submenu will be skipped and disabled.
  420. if PARAVIRT_GUEST
  421. source "arch/x86/xen/Kconfig"
  422. config KVM_CLOCK
  423. bool "KVM paravirtualized clock"
  424. select PARAVIRT
  425. select PARAVIRT_CLOCK
  426. ---help---
  427. Turning on this option will allow you to run a paravirtualized clock
  428. when running over the KVM hypervisor. Instead of relying on a PIT
  429. (or probably other) emulation by the underlying device model, the host
  430. provides the guest with timing infrastructure such as time of day, and
  431. system time
  432. config KVM_GUEST
  433. bool "KVM Guest support"
  434. select PARAVIRT
  435. ---help---
  436. This option enables various optimizations for running under the KVM
  437. hypervisor.
  438. source "arch/x86/lguest/Kconfig"
  439. config PARAVIRT
  440. bool "Enable paravirtualization code"
  441. ---help---
  442. This changes the kernel so it can modify itself when it is run
  443. under a hypervisor, potentially improving performance significantly
  444. over full virtualization. However, when run without a hypervisor
  445. the kernel is theoretically slower and slightly larger.
  446. config PARAVIRT_SPINLOCKS
  447. bool "Paravirtualization layer for spinlocks"
  448. depends on PARAVIRT && SMP && EXPERIMENTAL
  449. ---help---
  450. Paravirtualized spinlocks allow a pvops backend to replace the
  451. spinlock implementation with something virtualization-friendly
  452. (for example, block the virtual CPU rather than spinning).
  453. Unfortunately the downside is an up to 5% performance hit on
  454. native kernels, with various workloads.
  455. If you are unsure how to answer this question, answer N.
  456. config PARAVIRT_CLOCK
  457. bool
  458. endif
  459. config PARAVIRT_DEBUG
  460. bool "paravirt-ops debugging"
  461. depends on PARAVIRT && DEBUG_KERNEL
  462. ---help---
  463. Enable to debug paravirt_ops internals. Specifically, BUG if
  464. a paravirt_op is missing when it is called.
  465. config NO_BOOTMEM
  466. def_bool y
  467. config MEMTEST
  468. bool "Memtest"
  469. ---help---
  470. This option adds a kernel parameter 'memtest', which allows memtest
  471. to be set.
  472. memtest=0, mean disabled; -- default
  473. memtest=1, mean do 1 test pattern;
  474. ...
  475. memtest=4, mean do 4 test patterns.
  476. If you are unsure how to answer this question, answer N.
  477. config X86_SUMMIT_NUMA
  478. def_bool y
  479. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  480. config X86_CYCLONE_TIMER
  481. def_bool y
  482. depends on X86_32_NON_STANDARD
  483. source "arch/x86/Kconfig.cpu"
  484. config HPET_TIMER
  485. def_bool X86_64
  486. prompt "HPET Timer Support" if X86_32
  487. ---help---
  488. Use the IA-PC HPET (High Precision Event Timer) to manage
  489. time in preference to the PIT and RTC, if a HPET is
  490. present.
  491. HPET is the next generation timer replacing legacy 8254s.
  492. The HPET provides a stable time base on SMP
  493. systems, unlike the TSC, but it is more expensive to access,
  494. as it is off-chip. You can find the HPET spec at
  495. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  496. You can safely choose Y here. However, HPET will only be
  497. activated if the platform and the BIOS support this feature.
  498. Otherwise the 8254 will be used for timing services.
  499. Choose N to continue using the legacy 8254 timer.
  500. config HPET_EMULATE_RTC
  501. def_bool y
  502. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  503. config APB_TIMER
  504. def_bool y if MRST
  505. prompt "Langwell APB Timer Support" if X86_MRST
  506. help
  507. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  508. The APBT provides a stable time base on SMP
  509. systems, unlike the TSC, but it is more expensive to access,
  510. as it is off-chip. APB timers are always running regardless of CPU
  511. C states, they are used as per CPU clockevent device when possible.
  512. # Mark as expert because too many people got it wrong.
  513. # The code disables itself when not needed.
  514. config DMI
  515. default y
  516. bool "Enable DMI scanning" if EXPERT
  517. ---help---
  518. Enabled scanning of DMI to identify machine quirks. Say Y
  519. here unless you have verified that your setup is not
  520. affected by entries in the DMI blacklist. Required by PNP
  521. BIOS code.
  522. config GART_IOMMU
  523. bool "GART IOMMU support" if EXPERT
  524. default y
  525. select SWIOTLB
  526. depends on X86_64 && PCI && AMD_NB
  527. ---help---
  528. Support for full DMA access of devices with 32bit memory access only
  529. on systems with more than 3GB. This is usually needed for USB,
  530. sound, many IDE/SATA chipsets and some other devices.
  531. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  532. based hardware IOMMU and a software bounce buffer based IOMMU used
  533. on Intel systems and as fallback.
  534. The code is only active when needed (enough memory and limited
  535. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  536. too.
  537. config CALGARY_IOMMU
  538. bool "IBM Calgary IOMMU support"
  539. select SWIOTLB
  540. depends on X86_64 && PCI && EXPERIMENTAL
  541. ---help---
  542. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  543. systems. Needed to run systems with more than 3GB of memory
  544. properly with 32-bit PCI devices that do not support DAC
  545. (Double Address Cycle). Calgary also supports bus level
  546. isolation, where all DMAs pass through the IOMMU. This
  547. prevents them from going anywhere except their intended
  548. destination. This catches hard-to-find kernel bugs and
  549. mis-behaving drivers and devices that do not use the DMA-API
  550. properly to set up their DMA buffers. The IOMMU can be
  551. turned off at boot time with the iommu=off parameter.
  552. Normally the kernel will make the right choice by itself.
  553. If unsure, say Y.
  554. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  555. def_bool y
  556. prompt "Should Calgary be enabled by default?"
  557. depends on CALGARY_IOMMU
  558. ---help---
  559. Should Calgary be enabled by default? if you choose 'y', Calgary
  560. will be used (if it exists). If you choose 'n', Calgary will not be
  561. used even if it exists. If you choose 'n' and would like to use
  562. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  563. If unsure, say Y.
  564. config AMD_IOMMU
  565. bool "AMD IOMMU support"
  566. select SWIOTLB
  567. select PCI_MSI
  568. select PCI_IOV
  569. depends on X86_64 && PCI && ACPI
  570. ---help---
  571. With this option you can enable support for AMD IOMMU hardware in
  572. your system. An IOMMU is a hardware component which provides
  573. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  574. can isolate the the DMA memory of different devices and protect the
  575. system from misbehaving device drivers or hardware.
  576. You can find out if your system has an AMD IOMMU if you look into
  577. your BIOS for an option to enable it or if you have an IVRS ACPI
  578. table.
  579. config AMD_IOMMU_STATS
  580. bool "Export AMD IOMMU statistics to debugfs"
  581. depends on AMD_IOMMU
  582. select DEBUG_FS
  583. ---help---
  584. This option enables code in the AMD IOMMU driver to collect various
  585. statistics about whats happening in the driver and exports that
  586. information to userspace via debugfs.
  587. If unsure, say N.
  588. # need this always selected by IOMMU for the VIA workaround
  589. config SWIOTLB
  590. def_bool y if X86_64
  591. ---help---
  592. Support for software bounce buffers used on x86-64 systems
  593. which don't have a hardware IOMMU (e.g. the current generation
  594. of Intel's x86-64 CPUs). Using this PCI devices which can only
  595. access 32-bits of memory can be used on systems with more than
  596. 3 GB of memory. If unsure, say Y.
  597. config IOMMU_HELPER
  598. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  599. config IOMMU_API
  600. def_bool (AMD_IOMMU || DMAR)
  601. config MAXSMP
  602. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  603. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  604. select CPUMASK_OFFSTACK
  605. ---help---
  606. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  607. If unsure, say N.
  608. config NR_CPUS
  609. int "Maximum number of CPUs" if SMP && !MAXSMP
  610. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  611. range 2 512 if SMP && !MAXSMP
  612. default "1" if !SMP
  613. default "4096" if MAXSMP
  614. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  615. default "8" if SMP
  616. ---help---
  617. This allows you to specify the maximum number of CPUs which this
  618. kernel will support. The maximum supported value is 512 and the
  619. minimum value which makes sense is 2.
  620. This is purely to save memory - each supported CPU adds
  621. approximately eight kilobytes to the kernel image.
  622. config SCHED_SMT
  623. bool "SMT (Hyperthreading) scheduler support"
  624. depends on X86_HT
  625. ---help---
  626. SMT scheduler support improves the CPU scheduler's decision making
  627. when dealing with Intel Pentium 4 chips with HyperThreading at a
  628. cost of slightly increased overhead in some places. If unsure say
  629. N here.
  630. config SCHED_MC
  631. def_bool y
  632. prompt "Multi-core scheduler support"
  633. depends on X86_HT
  634. ---help---
  635. Multi-core scheduler support improves the CPU scheduler's decision
  636. making when dealing with multi-core CPU chips at a cost of slightly
  637. increased overhead in some places. If unsure say N here.
  638. config IRQ_TIME_ACCOUNTING
  639. bool "Fine granularity task level IRQ time accounting"
  640. default n
  641. ---help---
  642. Select this option to enable fine granularity task irq time
  643. accounting. This is done by reading a timestamp on each
  644. transitions between softirq and hardirq state, so there can be a
  645. small performance impact.
  646. If in doubt, say N here.
  647. source "kernel/Kconfig.preempt"
  648. config X86_UP_APIC
  649. bool "Local APIC support on uniprocessors"
  650. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  651. ---help---
  652. A local APIC (Advanced Programmable Interrupt Controller) is an
  653. integrated interrupt controller in the CPU. If you have a single-CPU
  654. system which has a processor with a local APIC, you can say Y here to
  655. enable and use it. If you say Y here even though your machine doesn't
  656. have a local APIC, then the kernel will still run with no slowdown at
  657. all. The local APIC supports CPU-generated self-interrupts (timer,
  658. performance counters), and the NMI watchdog which detects hard
  659. lockups.
  660. config X86_UP_IOAPIC
  661. bool "IO-APIC support on uniprocessors"
  662. depends on X86_UP_APIC
  663. ---help---
  664. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  665. SMP-capable replacement for PC-style interrupt controllers. Most
  666. SMP systems and many recent uniprocessor systems have one.
  667. If you have a single-CPU system with an IO-APIC, you can say Y here
  668. to use it. If you say Y here even though your machine doesn't have
  669. an IO-APIC, then the kernel will still run with no slowdown at all.
  670. config X86_LOCAL_APIC
  671. def_bool y
  672. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  673. config X86_IO_APIC
  674. def_bool y
  675. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
  676. config X86_VISWS_APIC
  677. def_bool y
  678. depends on X86_32 && X86_VISWS
  679. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  680. bool "Reroute for broken boot IRQs"
  681. depends on X86_IO_APIC
  682. ---help---
  683. This option enables a workaround that fixes a source of
  684. spurious interrupts. This is recommended when threaded
  685. interrupt handling is used on systems where the generation of
  686. superfluous "boot interrupts" cannot be disabled.
  687. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  688. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  689. kernel does during interrupt handling). On chipsets where this
  690. boot IRQ generation cannot be disabled, this workaround keeps
  691. the original IRQ line masked so that only the equivalent "boot
  692. IRQ" is delivered to the CPUs. The workaround also tells the
  693. kernel to set up the IRQ handler on the boot IRQ line. In this
  694. way only one interrupt is delivered to the kernel. Otherwise
  695. the spurious second interrupt may cause the kernel to bring
  696. down (vital) interrupt lines.
  697. Only affects "broken" chipsets. Interrupt sharing may be
  698. increased on these systems.
  699. config X86_MCE
  700. bool "Machine Check / overheating reporting"
  701. ---help---
  702. Machine Check support allows the processor to notify the
  703. kernel if it detects a problem (e.g. overheating, data corruption).
  704. The action the kernel takes depends on the severity of the problem,
  705. ranging from warning messages to halting the machine.
  706. config X86_MCE_INTEL
  707. def_bool y
  708. prompt "Intel MCE features"
  709. depends on X86_MCE && X86_LOCAL_APIC
  710. ---help---
  711. Additional support for intel specific MCE features such as
  712. the thermal monitor.
  713. config X86_MCE_AMD
  714. def_bool y
  715. prompt "AMD MCE features"
  716. depends on X86_MCE && X86_LOCAL_APIC
  717. ---help---
  718. Additional support for AMD specific MCE features such as
  719. the DRAM Error Threshold.
  720. config X86_ANCIENT_MCE
  721. bool "Support for old Pentium 5 / WinChip machine checks"
  722. depends on X86_32 && X86_MCE
  723. ---help---
  724. Include support for machine check handling on old Pentium 5 or WinChip
  725. systems. These typically need to be enabled explicitely on the command
  726. line.
  727. config X86_MCE_THRESHOLD
  728. depends on X86_MCE_AMD || X86_MCE_INTEL
  729. def_bool y
  730. config X86_MCE_INJECT
  731. depends on X86_MCE
  732. tristate "Machine check injector support"
  733. ---help---
  734. Provide support for injecting machine checks for testing purposes.
  735. If you don't know what a machine check is and you don't do kernel
  736. QA it is safe to say n.
  737. config X86_THERMAL_VECTOR
  738. def_bool y
  739. depends on X86_MCE_INTEL
  740. config VM86
  741. bool "Enable VM86 support" if EXPERT
  742. default y
  743. depends on X86_32
  744. ---help---
  745. This option is required by programs like DOSEMU to run 16-bit legacy
  746. code on X86 processors. It also may be needed by software like
  747. XFree86 to initialize some video cards via BIOS. Disabling this
  748. option saves about 6k.
  749. config TOSHIBA
  750. tristate "Toshiba Laptop support"
  751. depends on X86_32
  752. ---help---
  753. This adds a driver to safely access the System Management Mode of
  754. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  755. not work on models with a Phoenix BIOS. The System Management Mode
  756. is used to set the BIOS and power saving options on Toshiba portables.
  757. For information on utilities to make use of this driver see the
  758. Toshiba Linux utilities web site at:
  759. <http://www.buzzard.org.uk/toshiba/>.
  760. Say Y if you intend to run this kernel on a Toshiba portable.
  761. Say N otherwise.
  762. config I8K
  763. tristate "Dell laptop support"
  764. ---help---
  765. This adds a driver to safely access the System Management Mode
  766. of the CPU on the Dell Inspiron 8000. The System Management Mode
  767. is used to read cpu temperature and cooling fan status and to
  768. control the fans on the I8K portables.
  769. This driver has been tested only on the Inspiron 8000 but it may
  770. also work with other Dell laptops. You can force loading on other
  771. models by passing the parameter `force=1' to the module. Use at
  772. your own risk.
  773. For information on utilities to make use of this driver see the
  774. I8K Linux utilities web site at:
  775. <http://people.debian.org/~dz/i8k/>
  776. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  777. Say N otherwise.
  778. config X86_REBOOTFIXUPS
  779. bool "Enable X86 board specific fixups for reboot"
  780. depends on X86_32
  781. ---help---
  782. This enables chipset and/or board specific fixups to be done
  783. in order to get reboot to work correctly. This is only needed on
  784. some combinations of hardware and BIOS. The symptom, for which
  785. this config is intended, is when reboot ends with a stalled/hung
  786. system.
  787. Currently, the only fixup is for the Geode machines using
  788. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  789. Say Y if you want to enable the fixup. Currently, it's safe to
  790. enable this option even if you don't need it.
  791. Say N otherwise.
  792. config MICROCODE
  793. tristate "/dev/cpu/microcode - microcode support"
  794. select FW_LOADER
  795. ---help---
  796. If you say Y here, you will be able to update the microcode on
  797. certain Intel and AMD processors. The Intel support is for the
  798. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  799. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  800. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  801. You will obviously need the actual microcode binary data itself
  802. which is not shipped with the Linux kernel.
  803. This option selects the general module only, you need to select
  804. at least one vendor specific module as well.
  805. To compile this driver as a module, choose M here: the
  806. module will be called microcode.
  807. config MICROCODE_INTEL
  808. bool "Intel microcode patch loading support"
  809. depends on MICROCODE
  810. default MICROCODE
  811. select FW_LOADER
  812. ---help---
  813. This options enables microcode patch loading support for Intel
  814. processors.
  815. For latest news and information on obtaining all the required
  816. Intel ingredients for this driver, check:
  817. <http://www.urbanmyth.org/microcode/>.
  818. config MICROCODE_AMD
  819. bool "AMD microcode patch loading support"
  820. depends on MICROCODE
  821. select FW_LOADER
  822. ---help---
  823. If you select this option, microcode patch loading support for AMD
  824. processors will be enabled.
  825. config MICROCODE_OLD_INTERFACE
  826. def_bool y
  827. depends on MICROCODE
  828. config X86_MSR
  829. tristate "/dev/cpu/*/msr - Model-specific register support"
  830. ---help---
  831. This device gives privileged processes access to the x86
  832. Model-Specific Registers (MSRs). It is a character device with
  833. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  834. MSR accesses are directed to a specific CPU on multi-processor
  835. systems.
  836. config X86_CPUID
  837. tristate "/dev/cpu/*/cpuid - CPU information support"
  838. ---help---
  839. This device gives processes access to the x86 CPUID instruction to
  840. be executed on a specific processor. It is a character device
  841. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  842. /dev/cpu/31/cpuid.
  843. choice
  844. prompt "High Memory Support"
  845. default HIGHMEM64G if X86_NUMAQ
  846. default HIGHMEM4G
  847. depends on X86_32
  848. config NOHIGHMEM
  849. bool "off"
  850. depends on !X86_NUMAQ
  851. ---help---
  852. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  853. However, the address space of 32-bit x86 processors is only 4
  854. Gigabytes large. That means that, if you have a large amount of
  855. physical memory, not all of it can be "permanently mapped" by the
  856. kernel. The physical memory that's not permanently mapped is called
  857. "high memory".
  858. If you are compiling a kernel which will never run on a machine with
  859. more than 1 Gigabyte total physical RAM, answer "off" here (default
  860. choice and suitable for most users). This will result in a "3GB/1GB"
  861. split: 3GB are mapped so that each process sees a 3GB virtual memory
  862. space and the remaining part of the 4GB virtual memory space is used
  863. by the kernel to permanently map as much physical memory as
  864. possible.
  865. If the machine has between 1 and 4 Gigabytes physical RAM, then
  866. answer "4GB" here.
  867. If more than 4 Gigabytes is used then answer "64GB" here. This
  868. selection turns Intel PAE (Physical Address Extension) mode on.
  869. PAE implements 3-level paging on IA32 processors. PAE is fully
  870. supported by Linux, PAE mode is implemented on all recent Intel
  871. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  872. then the kernel will not boot on CPUs that don't support PAE!
  873. The actual amount of total physical memory will either be
  874. auto detected or can be forced by using a kernel command line option
  875. such as "mem=256M". (Try "man bootparam" or see the documentation of
  876. your boot loader (lilo or loadlin) about how to pass options to the
  877. kernel at boot time.)
  878. If unsure, say "off".
  879. config HIGHMEM4G
  880. bool "4GB"
  881. depends on !X86_NUMAQ
  882. ---help---
  883. Select this if you have a 32-bit processor and between 1 and 4
  884. gigabytes of physical RAM.
  885. config HIGHMEM64G
  886. bool "64GB"
  887. depends on !M386 && !M486
  888. select X86_PAE
  889. ---help---
  890. Select this if you have a 32-bit processor and more than 4
  891. gigabytes of physical RAM.
  892. endchoice
  893. choice
  894. depends on EXPERIMENTAL
  895. prompt "Memory split" if EXPERT
  896. default VMSPLIT_3G
  897. depends on X86_32
  898. ---help---
  899. Select the desired split between kernel and user memory.
  900. If the address range available to the kernel is less than the
  901. physical memory installed, the remaining memory will be available
  902. as "high memory". Accessing high memory is a little more costly
  903. than low memory, as it needs to be mapped into the kernel first.
  904. Note that increasing the kernel address space limits the range
  905. available to user programs, making the address space there
  906. tighter. Selecting anything other than the default 3G/1G split
  907. will also likely make your kernel incompatible with binary-only
  908. kernel modules.
  909. If you are not absolutely sure what you are doing, leave this
  910. option alone!
  911. config VMSPLIT_3G
  912. bool "3G/1G user/kernel split"
  913. config VMSPLIT_3G_OPT
  914. depends on !X86_PAE
  915. bool "3G/1G user/kernel split (for full 1G low memory)"
  916. config VMSPLIT_2G
  917. bool "2G/2G user/kernel split"
  918. config VMSPLIT_2G_OPT
  919. depends on !X86_PAE
  920. bool "2G/2G user/kernel split (for full 2G low memory)"
  921. config VMSPLIT_1G
  922. bool "1G/3G user/kernel split"
  923. endchoice
  924. config PAGE_OFFSET
  925. hex
  926. default 0xB0000000 if VMSPLIT_3G_OPT
  927. default 0x80000000 if VMSPLIT_2G
  928. default 0x78000000 if VMSPLIT_2G_OPT
  929. default 0x40000000 if VMSPLIT_1G
  930. default 0xC0000000
  931. depends on X86_32
  932. config HIGHMEM
  933. def_bool y
  934. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  935. config X86_PAE
  936. bool "PAE (Physical Address Extension) Support"
  937. depends on X86_32 && !HIGHMEM4G
  938. ---help---
  939. PAE is required for NX support, and furthermore enables
  940. larger swapspace support for non-overcommit purposes. It
  941. has the cost of more pagetable lookup overhead, and also
  942. consumes more pagetable space per process.
  943. config ARCH_PHYS_ADDR_T_64BIT
  944. def_bool X86_64 || X86_PAE
  945. config ARCH_DMA_ADDR_T_64BIT
  946. def_bool X86_64 || HIGHMEM64G
  947. config DIRECT_GBPAGES
  948. bool "Enable 1GB pages for kernel pagetables" if EXPERT
  949. default y
  950. depends on X86_64
  951. ---help---
  952. Allow the kernel linear mapping to use 1GB pages on CPUs that
  953. support it. This can improve the kernel's performance a tiny bit by
  954. reducing TLB pressure. If in doubt, say "Y".
  955. # Common NUMA Features
  956. config NUMA
  957. bool "Numa Memory Allocation and Scheduler Support"
  958. depends on SMP
  959. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  960. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  961. ---help---
  962. Enable NUMA (Non Uniform Memory Access) support.
  963. The kernel will try to allocate memory used by a CPU on the
  964. local memory controller of the CPU and add some more
  965. NUMA awareness to the kernel.
  966. For 64-bit this is recommended if the system is Intel Core i7
  967. (or later), AMD Opteron, or EM64T NUMA.
  968. For 32-bit this is only needed on (rare) 32-bit-only platforms
  969. that support NUMA topologies, such as NUMAQ / Summit, or if you
  970. boot a 32-bit kernel on a 64-bit NUMA platform.
  971. Otherwise, you should say N.
  972. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  973. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  974. config AMD_NUMA
  975. def_bool y
  976. prompt "Old style AMD Opteron NUMA detection"
  977. depends on NUMA && PCI
  978. ---help---
  979. Enable AMD NUMA node topology detection. You should say Y here if
  980. you have a multi processor AMD system. This uses an old method to
  981. read the NUMA configuration directly from the builtin Northbridge
  982. of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
  983. which also takes priority if both are compiled in.
  984. config X86_64_ACPI_NUMA
  985. def_bool y
  986. prompt "ACPI NUMA detection"
  987. depends on X86_64 && NUMA && ACPI && PCI
  988. select ACPI_NUMA
  989. ---help---
  990. Enable ACPI SRAT based node topology detection.
  991. # Some NUMA nodes have memory ranges that span
  992. # other nodes. Even though a pfn is valid and
  993. # between a node's start and end pfns, it may not
  994. # reside on that node. See memmap_init_zone()
  995. # for details.
  996. config NODES_SPAN_OTHER_NODES
  997. def_bool y
  998. depends on X86_64_ACPI_NUMA
  999. config NUMA_EMU
  1000. bool "NUMA emulation"
  1001. depends on NUMA
  1002. ---help---
  1003. Enable NUMA emulation. A flat machine will be split
  1004. into virtual nodes when booted with "numa=fake=N", where N is the
  1005. number of nodes. This is only useful for debugging.
  1006. config NODES_SHIFT
  1007. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1008. range 1 10
  1009. default "10" if MAXSMP
  1010. default "6" if X86_64
  1011. default "4" if X86_NUMAQ
  1012. default "3"
  1013. depends on NEED_MULTIPLE_NODES
  1014. ---help---
  1015. Specify the maximum number of NUMA Nodes available on the target
  1016. system. Increases memory reserved to accommodate various tables.
  1017. config HAVE_ARCH_BOOTMEM
  1018. def_bool y
  1019. depends on X86_32 && NUMA
  1020. config HAVE_ARCH_ALLOC_REMAP
  1021. def_bool y
  1022. depends on X86_32 && NUMA
  1023. config ARCH_HAVE_MEMORY_PRESENT
  1024. def_bool y
  1025. depends on X86_32 && DISCONTIGMEM
  1026. config NEED_NODE_MEMMAP_SIZE
  1027. def_bool y
  1028. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1029. config ARCH_FLATMEM_ENABLE
  1030. def_bool y
  1031. depends on X86_32 && !NUMA
  1032. config ARCH_DISCONTIGMEM_ENABLE
  1033. def_bool y
  1034. depends on NUMA && X86_32
  1035. config ARCH_DISCONTIGMEM_DEFAULT
  1036. def_bool y
  1037. depends on NUMA && X86_32
  1038. config ARCH_SPARSEMEM_ENABLE
  1039. def_bool y
  1040. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1041. select SPARSEMEM_STATIC if X86_32
  1042. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1043. config ARCH_SPARSEMEM_DEFAULT
  1044. def_bool y
  1045. depends on X86_64
  1046. config ARCH_SELECT_MEMORY_MODEL
  1047. def_bool y
  1048. depends on ARCH_SPARSEMEM_ENABLE
  1049. config ARCH_MEMORY_PROBE
  1050. def_bool X86_64
  1051. depends on MEMORY_HOTPLUG
  1052. config ARCH_PROC_KCORE_TEXT
  1053. def_bool y
  1054. depends on X86_64 && PROC_KCORE
  1055. config ILLEGAL_POINTER_VALUE
  1056. hex
  1057. default 0 if X86_32
  1058. default 0xdead000000000000 if X86_64
  1059. source "mm/Kconfig"
  1060. config HIGHPTE
  1061. bool "Allocate 3rd-level pagetables from highmem"
  1062. depends on HIGHMEM
  1063. ---help---
  1064. The VM uses one page table entry for each page of physical memory.
  1065. For systems with a lot of RAM, this can be wasteful of precious
  1066. low memory. Setting this option will put user-space page table
  1067. entries in high memory.
  1068. config X86_CHECK_BIOS_CORRUPTION
  1069. bool "Check for low memory corruption"
  1070. ---help---
  1071. Periodically check for memory corruption in low memory, which
  1072. is suspected to be caused by BIOS. Even when enabled in the
  1073. configuration, it is disabled at runtime. Enable it by
  1074. setting "memory_corruption_check=1" on the kernel command
  1075. line. By default it scans the low 64k of memory every 60
  1076. seconds; see the memory_corruption_check_size and
  1077. memory_corruption_check_period parameters in
  1078. Documentation/kernel-parameters.txt to adjust this.
  1079. When enabled with the default parameters, this option has
  1080. almost no overhead, as it reserves a relatively small amount
  1081. of memory and scans it infrequently. It both detects corruption
  1082. and prevents it from affecting the running system.
  1083. It is, however, intended as a diagnostic tool; if repeatable
  1084. BIOS-originated corruption always affects the same memory,
  1085. you can use memmap= to prevent the kernel from using that
  1086. memory.
  1087. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1088. bool "Set the default setting of memory_corruption_check"
  1089. depends on X86_CHECK_BIOS_CORRUPTION
  1090. default y
  1091. ---help---
  1092. Set whether the default state of memory_corruption_check is
  1093. on or off.
  1094. config X86_RESERVE_LOW
  1095. int "Amount of low memory, in kilobytes, to reserve for the BIOS"
  1096. default 64
  1097. range 4 640
  1098. ---help---
  1099. Specify the amount of low memory to reserve for the BIOS.
  1100. The first page contains BIOS data structures that the kernel
  1101. must not use, so that page must always be reserved.
  1102. By default we reserve the first 64K of physical RAM, as a
  1103. number of BIOSes are known to corrupt that memory range
  1104. during events such as suspend/resume or monitor cable
  1105. insertion, so it must not be used by the kernel.
  1106. You can set this to 4 if you are absolutely sure that you
  1107. trust the BIOS to get all its memory reservations and usages
  1108. right. If you know your BIOS have problems beyond the
  1109. default 64K area, you can set this to 640 to avoid using the
  1110. entire low memory range.
  1111. If you have doubts about the BIOS (e.g. suspend/resume does
  1112. not work or there's kernel crashes after certain hardware
  1113. hotplug events) then you might want to enable
  1114. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
  1115. typical corruption patterns.
  1116. Leave this to the default value of 64 if you are unsure.
  1117. config MATH_EMULATION
  1118. bool
  1119. prompt "Math emulation" if X86_32
  1120. ---help---
  1121. Linux can emulate a math coprocessor (used for floating point
  1122. operations) if you don't have one. 486DX and Pentium processors have
  1123. a math coprocessor built in, 486SX and 386 do not, unless you added
  1124. a 487DX or 387, respectively. (The messages during boot time can
  1125. give you some hints here ["man dmesg"].) Everyone needs either a
  1126. coprocessor or this emulation.
  1127. If you don't have a math coprocessor, you need to say Y here; if you
  1128. say Y here even though you have a coprocessor, the coprocessor will
  1129. be used nevertheless. (This behavior can be changed with the kernel
  1130. command line option "no387", which comes handy if your coprocessor
  1131. is broken. Try "man bootparam" or see the documentation of your boot
  1132. loader (lilo or loadlin) about how to pass options to the kernel at
  1133. boot time.) This means that it is a good idea to say Y here if you
  1134. intend to use this kernel on different machines.
  1135. More information about the internals of the Linux math coprocessor
  1136. emulation can be found in <file:arch/x86/math-emu/README>.
  1137. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1138. kernel, it won't hurt.
  1139. config MTRR
  1140. def_bool y
  1141. prompt "MTRR (Memory Type Range Register) support" if EXPERT
  1142. ---help---
  1143. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1144. the Memory Type Range Registers (MTRRs) may be used to control
  1145. processor access to memory ranges. This is most useful if you have
  1146. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1147. allows bus write transfers to be combined into a larger transfer
  1148. before bursting over the PCI/AGP bus. This can increase performance
  1149. of image write operations 2.5 times or more. Saying Y here creates a
  1150. /proc/mtrr file which may be used to manipulate your processor's
  1151. MTRRs. Typically the X server should use this.
  1152. This code has a reasonably generic interface so that similar
  1153. control registers on other processors can be easily supported
  1154. as well:
  1155. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1156. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1157. these, the ARRs are used to emulate the MTRRs.
  1158. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1159. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1160. write-combining. All of these processors are supported by this code
  1161. and it makes sense to say Y here if you have one of them.
  1162. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1163. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1164. can lead to all sorts of problems, so it's good to say Y here.
  1165. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1166. just add about 9 KB to your kernel.
  1167. See <file:Documentation/x86/mtrr.txt> for more information.
  1168. config MTRR_SANITIZER
  1169. def_bool y
  1170. prompt "MTRR cleanup support"
  1171. depends on MTRR
  1172. ---help---
  1173. Convert MTRR layout from continuous to discrete, so X drivers can
  1174. add writeback entries.
  1175. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1176. The largest mtrr entry size for a continuous block can be set with
  1177. mtrr_chunk_size.
  1178. If unsure, say Y.
  1179. config MTRR_SANITIZER_ENABLE_DEFAULT
  1180. int "MTRR cleanup enable value (0-1)"
  1181. range 0 1
  1182. default "0"
  1183. depends on MTRR_SANITIZER
  1184. ---help---
  1185. Enable mtrr cleanup default value
  1186. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1187. int "MTRR cleanup spare reg num (0-7)"
  1188. range 0 7
  1189. default "1"
  1190. depends on MTRR_SANITIZER
  1191. ---help---
  1192. mtrr cleanup spare entries default, it can be changed via
  1193. mtrr_spare_reg_nr=N on the kernel command line.
  1194. config X86_PAT
  1195. def_bool y
  1196. prompt "x86 PAT support" if EXPERT
  1197. depends on MTRR
  1198. ---help---
  1199. Use PAT attributes to setup page level cache control.
  1200. PATs are the modern equivalents of MTRRs and are much more
  1201. flexible than MTRRs.
  1202. Say N here if you see bootup problems (boot crash, boot hang,
  1203. spontaneous reboots) or a non-working video driver.
  1204. If unsure, say Y.
  1205. config ARCH_USES_PG_UNCACHED
  1206. def_bool y
  1207. depends on X86_PAT
  1208. config EFI
  1209. bool "EFI runtime service support"
  1210. depends on ACPI
  1211. ---help---
  1212. This enables the kernel to use EFI runtime services that are
  1213. available (such as the EFI variable services).
  1214. This option is only useful on systems that have EFI firmware.
  1215. In addition, you should use the latest ELILO loader available
  1216. at <http://elilo.sourceforge.net> in order to take advantage
  1217. of EFI runtime services. However, even with this option, the
  1218. resultant kernel should continue to boot on existing non-EFI
  1219. platforms.
  1220. config SECCOMP
  1221. def_bool y
  1222. prompt "Enable seccomp to safely compute untrusted bytecode"
  1223. ---help---
  1224. This kernel feature is useful for number crunching applications
  1225. that may need to compute untrusted bytecode during their
  1226. execution. By using pipes or other transports made available to
  1227. the process as file descriptors supporting the read/write
  1228. syscalls, it's possible to isolate those applications in
  1229. their own address space using seccomp. Once seccomp is
  1230. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1231. and the task is only allowed to execute a few safe syscalls
  1232. defined by each seccomp mode.
  1233. If unsure, say Y. Only embedded should say N here.
  1234. config CC_STACKPROTECTOR
  1235. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1236. ---help---
  1237. This option turns on the -fstack-protector GCC feature. This
  1238. feature puts, at the beginning of functions, a canary value on
  1239. the stack just before the return address, and validates
  1240. the value just before actually returning. Stack based buffer
  1241. overflows (that need to overwrite this return address) now also
  1242. overwrite the canary, which gets detected and the attack is then
  1243. neutralized via a kernel panic.
  1244. This feature requires gcc version 4.2 or above, or a distribution
  1245. gcc with the feature backported. Older versions are automatically
  1246. detected and for those versions, this configuration option is
  1247. ignored. (and a warning is printed during bootup)
  1248. source kernel/Kconfig.hz
  1249. config KEXEC
  1250. bool "kexec system call"
  1251. ---help---
  1252. kexec is a system call that implements the ability to shutdown your
  1253. current kernel, and to start another kernel. It is like a reboot
  1254. but it is independent of the system firmware. And like a reboot
  1255. you can start any kernel with it, not just Linux.
  1256. The name comes from the similarity to the exec system call.
  1257. It is an ongoing process to be certain the hardware in a machine
  1258. is properly shutdown, so do not be surprised if this code does not
  1259. initially work for you. It may help to enable device hotplugging
  1260. support. As of this writing the exact hardware interface is
  1261. strongly in flux, so no good recommendation can be made.
  1262. config CRASH_DUMP
  1263. bool "kernel crash dumps"
  1264. depends on X86_64 || (X86_32 && HIGHMEM)
  1265. ---help---
  1266. Generate crash dump after being started by kexec.
  1267. This should be normally only set in special crash dump kernels
  1268. which are loaded in the main kernel with kexec-tools into
  1269. a specially reserved region and then later executed after
  1270. a crash by kdump/kexec. The crash dump kernel must be compiled
  1271. to a memory address not used by the main kernel or BIOS using
  1272. PHYSICAL_START, or it must be built as a relocatable image
  1273. (CONFIG_RELOCATABLE=y).
  1274. For more details see Documentation/kdump/kdump.txt
  1275. config KEXEC_JUMP
  1276. bool "kexec jump (EXPERIMENTAL)"
  1277. depends on EXPERIMENTAL
  1278. depends on KEXEC && HIBERNATION
  1279. ---help---
  1280. Jump between original kernel and kexeced kernel and invoke
  1281. code in physical address mode via KEXEC
  1282. config PHYSICAL_START
  1283. hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
  1284. default "0x1000000"
  1285. ---help---
  1286. This gives the physical address where the kernel is loaded.
  1287. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1288. bzImage will decompress itself to above physical address and
  1289. run from there. Otherwise, bzImage will run from the address where
  1290. it has been loaded by the boot loader and will ignore above physical
  1291. address.
  1292. In normal kdump cases one does not have to set/change this option
  1293. as now bzImage can be compiled as a completely relocatable image
  1294. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1295. address. This option is mainly useful for the folks who don't want
  1296. to use a bzImage for capturing the crash dump and want to use a
  1297. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1298. to be specifically compiled to run from a specific memory area
  1299. (normally a reserved region) and this option comes handy.
  1300. So if you are using bzImage for capturing the crash dump,
  1301. leave the value here unchanged to 0x1000000 and set
  1302. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1303. for capturing the crash dump change this value to start of
  1304. the reserved region. In other words, it can be set based on
  1305. the "X" value as specified in the "crashkernel=YM@XM"
  1306. command line boot parameter passed to the panic-ed
  1307. kernel. Please take a look at Documentation/kdump/kdump.txt
  1308. for more details about crash dumps.
  1309. Usage of bzImage for capturing the crash dump is recommended as
  1310. one does not have to build two kernels. Same kernel can be used
  1311. as production kernel and capture kernel. Above option should have
  1312. gone away after relocatable bzImage support is introduced. But it
  1313. is present because there are users out there who continue to use
  1314. vmlinux for dump capture. This option should go away down the
  1315. line.
  1316. Don't change this unless you know what you are doing.
  1317. config RELOCATABLE
  1318. bool "Build a relocatable kernel"
  1319. default y
  1320. ---help---
  1321. This builds a kernel image that retains relocation information
  1322. so it can be loaded someplace besides the default 1MB.
  1323. The relocations tend to make the kernel binary about 10% larger,
  1324. but are discarded at runtime.
  1325. One use is for the kexec on panic case where the recovery kernel
  1326. must live at a different physical address than the primary
  1327. kernel.
  1328. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1329. it has been loaded at and the compile time physical address
  1330. (CONFIG_PHYSICAL_START) is ignored.
  1331. # Relocation on x86-32 needs some additional build support
  1332. config X86_NEED_RELOCS
  1333. def_bool y
  1334. depends on X86_32 && RELOCATABLE
  1335. config PHYSICAL_ALIGN
  1336. hex "Alignment value to which kernel should be aligned" if X86_32
  1337. default "0x1000000"
  1338. range 0x2000 0x1000000
  1339. ---help---
  1340. This value puts the alignment restrictions on physical address
  1341. where kernel is loaded and run from. Kernel is compiled for an
  1342. address which meets above alignment restriction.
  1343. If bootloader loads the kernel at a non-aligned address and
  1344. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1345. address aligned to above value and run from there.
  1346. If bootloader loads the kernel at a non-aligned address and
  1347. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1348. load address and decompress itself to the address it has been
  1349. compiled for and run from there. The address for which kernel is
  1350. compiled already meets above alignment restrictions. Hence the
  1351. end result is that kernel runs from a physical address meeting
  1352. above alignment restrictions.
  1353. Don't change this unless you know what you are doing.
  1354. config HOTPLUG_CPU
  1355. bool "Support for hot-pluggable CPUs"
  1356. depends on SMP && HOTPLUG
  1357. ---help---
  1358. Say Y here to allow turning CPUs off and on. CPUs can be
  1359. controlled through /sys/devices/system/cpu.
  1360. ( Note: power management support will enable this option
  1361. automatically on SMP systems. )
  1362. Say N if you want to disable CPU hotplug.
  1363. config COMPAT_VDSO
  1364. def_bool y
  1365. prompt "Compat VDSO support"
  1366. depends on X86_32 || IA32_EMULATION
  1367. ---help---
  1368. Map the 32-bit VDSO to the predictable old-style address too.
  1369. Say N here if you are running a sufficiently recent glibc
  1370. version (2.3.3 or later), to remove the high-mapped
  1371. VDSO mapping and to exclusively use the randomized VDSO.
  1372. If unsure, say Y.
  1373. config CMDLINE_BOOL
  1374. bool "Built-in kernel command line"
  1375. ---help---
  1376. Allow for specifying boot arguments to the kernel at
  1377. build time. On some systems (e.g. embedded ones), it is
  1378. necessary or convenient to provide some or all of the
  1379. kernel boot arguments with the kernel itself (that is,
  1380. to not rely on the boot loader to provide them.)
  1381. To compile command line arguments into the kernel,
  1382. set this option to 'Y', then fill in the
  1383. the boot arguments in CONFIG_CMDLINE.
  1384. Systems with fully functional boot loaders (i.e. non-embedded)
  1385. should leave this option set to 'N'.
  1386. config CMDLINE
  1387. string "Built-in kernel command string"
  1388. depends on CMDLINE_BOOL
  1389. default ""
  1390. ---help---
  1391. Enter arguments here that should be compiled into the kernel
  1392. image and used at boot time. If the boot loader provides a
  1393. command line at boot time, it is appended to this string to
  1394. form the full kernel command line, when the system boots.
  1395. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1396. change this behavior.
  1397. In most cases, the command line (whether built-in or provided
  1398. by the boot loader) should specify the device for the root
  1399. file system.
  1400. config CMDLINE_OVERRIDE
  1401. bool "Built-in command line overrides boot loader arguments"
  1402. depends on CMDLINE_BOOL
  1403. ---help---
  1404. Set this option to 'Y' to have the kernel ignore the boot loader
  1405. command line, and use ONLY the built-in command line.
  1406. This is used to work around broken boot loaders. This should
  1407. be set to 'N' under normal conditions.
  1408. endmenu
  1409. config ARCH_ENABLE_MEMORY_HOTPLUG
  1410. def_bool y
  1411. depends on X86_64 || (X86_32 && HIGHMEM)
  1412. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1413. def_bool y
  1414. depends on MEMORY_HOTPLUG
  1415. config USE_PERCPU_NUMA_NODE_ID
  1416. def_bool y
  1417. depends on NUMA
  1418. menu "Power management and ACPI options"
  1419. config ARCH_HIBERNATION_HEADER
  1420. def_bool y
  1421. depends on X86_64 && HIBERNATION
  1422. source "kernel/power/Kconfig"
  1423. source "drivers/acpi/Kconfig"
  1424. source "drivers/sfi/Kconfig"
  1425. config X86_APM_BOOT
  1426. def_bool y
  1427. depends on APM || APM_MODULE
  1428. menuconfig APM
  1429. tristate "APM (Advanced Power Management) BIOS support"
  1430. depends on X86_32 && PM_SLEEP
  1431. ---help---
  1432. APM is a BIOS specification for saving power using several different
  1433. techniques. This is mostly useful for battery powered laptops with
  1434. APM compliant BIOSes. If you say Y here, the system time will be
  1435. reset after a RESUME operation, the /proc/apm device will provide
  1436. battery status information, and user-space programs will receive
  1437. notification of APM "events" (e.g. battery status change).
  1438. If you select "Y" here, you can disable actual use of the APM
  1439. BIOS by passing the "apm=off" option to the kernel at boot time.
  1440. Note that the APM support is almost completely disabled for
  1441. machines with more than one CPU.
  1442. In order to use APM, you will need supporting software. For location
  1443. and more information, read <file:Documentation/power/pm.txt> and the
  1444. Battery Powered Linux mini-HOWTO, available from
  1445. <http://www.tldp.org/docs.html#howto>.
  1446. This driver does not spin down disk drives (see the hdparm(8)
  1447. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1448. VESA-compliant "green" monitors.
  1449. This driver does not support the TI 4000M TravelMate and the ACER
  1450. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1451. desktop machines also don't have compliant BIOSes, and this driver
  1452. may cause those machines to panic during the boot phase.
  1453. Generally, if you don't have a battery in your machine, there isn't
  1454. much point in using this driver and you should say N. If you get
  1455. random kernel OOPSes or reboots that don't seem to be related to
  1456. anything, try disabling/enabling this option (or disabling/enabling
  1457. APM in your BIOS).
  1458. Some other things you should try when experiencing seemingly random,
  1459. "weird" problems:
  1460. 1) make sure that you have enough swap space and that it is
  1461. enabled.
  1462. 2) pass the "no-hlt" option to the kernel
  1463. 3) switch on floating point emulation in the kernel and pass
  1464. the "no387" option to the kernel
  1465. 4) pass the "floppy=nodma" option to the kernel
  1466. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1467. all but the first 4 MB of RAM)
  1468. 6) make sure that the CPU is not over clocked.
  1469. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1470. 8) disable the cache from your BIOS settings
  1471. 9) install a fan for the video card or exchange video RAM
  1472. 10) install a better fan for the CPU
  1473. 11) exchange RAM chips
  1474. 12) exchange the motherboard.
  1475. To compile this driver as a module, choose M here: the
  1476. module will be called apm.
  1477. if APM
  1478. config APM_IGNORE_USER_SUSPEND
  1479. bool "Ignore USER SUSPEND"
  1480. ---help---
  1481. This option will ignore USER SUSPEND requests. On machines with a
  1482. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1483. series notebooks, it is necessary to say Y because of a BIOS bug.
  1484. config APM_DO_ENABLE
  1485. bool "Enable PM at boot time"
  1486. ---help---
  1487. Enable APM features at boot time. From page 36 of the APM BIOS
  1488. specification: "When disabled, the APM BIOS does not automatically
  1489. power manage devices, enter the Standby State, enter the Suspend
  1490. State, or take power saving steps in response to CPU Idle calls."
  1491. This driver will make CPU Idle calls when Linux is idle (unless this
  1492. feature is turned off -- see "Do CPU IDLE calls", below). This
  1493. should always save battery power, but more complicated APM features
  1494. will be dependent on your BIOS implementation. You may need to turn
  1495. this option off if your computer hangs at boot time when using APM
  1496. support, or if it beeps continuously instead of suspending. Turn
  1497. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1498. T400CDT. This is off by default since most machines do fine without
  1499. this feature.
  1500. config APM_CPU_IDLE
  1501. bool "Make CPU Idle calls when idle"
  1502. ---help---
  1503. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1504. On some machines, this can activate improved power savings, such as
  1505. a slowed CPU clock rate, when the machine is idle. These idle calls
  1506. are made after the idle loop has run for some length of time (e.g.,
  1507. 333 mS). On some machines, this will cause a hang at boot time or
  1508. whenever the CPU becomes idle. (On machines with more than one CPU,
  1509. this option does nothing.)
  1510. config APM_DISPLAY_BLANK
  1511. bool "Enable console blanking using APM"
  1512. ---help---
  1513. Enable console blanking using the APM. Some laptops can use this to
  1514. turn off the LCD backlight when the screen blanker of the Linux
  1515. virtual console blanks the screen. Note that this is only used by
  1516. the virtual console screen blanker, and won't turn off the backlight
  1517. when using the X Window system. This also doesn't have anything to
  1518. do with your VESA-compliant power-saving monitor. Further, this
  1519. option doesn't work for all laptops -- it might not turn off your
  1520. backlight at all, or it might print a lot of errors to the console,
  1521. especially if you are using gpm.
  1522. config APM_ALLOW_INTS
  1523. bool "Allow interrupts during APM BIOS calls"
  1524. ---help---
  1525. Normally we disable external interrupts while we are making calls to
  1526. the APM BIOS as a measure to lessen the effects of a badly behaving
  1527. BIOS implementation. The BIOS should reenable interrupts if it
  1528. needs to. Unfortunately, some BIOSes do not -- especially those in
  1529. many of the newer IBM Thinkpads. If you experience hangs when you
  1530. suspend, try setting this to Y. Otherwise, say N.
  1531. endif # APM
  1532. source "drivers/cpufreq/Kconfig"
  1533. source "drivers/cpuidle/Kconfig"
  1534. source "drivers/idle/Kconfig"
  1535. endmenu
  1536. menu "Bus options (PCI etc.)"
  1537. config PCI
  1538. bool "PCI support"
  1539. default y
  1540. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1541. ---help---
  1542. Find out whether you have a PCI motherboard. PCI is the name of a
  1543. bus system, i.e. the way the CPU talks to the other stuff inside
  1544. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1545. VESA. If you have PCI, say Y, otherwise N.
  1546. choice
  1547. prompt "PCI access mode"
  1548. depends on X86_32 && PCI
  1549. default PCI_GOANY
  1550. ---help---
  1551. On PCI systems, the BIOS can be used to detect the PCI devices and
  1552. determine their configuration. However, some old PCI motherboards
  1553. have BIOS bugs and may crash if this is done. Also, some embedded
  1554. PCI-based systems don't have any BIOS at all. Linux can also try to
  1555. detect the PCI hardware directly without using the BIOS.
  1556. With this option, you can specify how Linux should detect the
  1557. PCI devices. If you choose "BIOS", the BIOS will be used,
  1558. if you choose "Direct", the BIOS won't be used, and if you
  1559. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1560. If you choose "Any", the kernel will try MMCONFIG, then the
  1561. direct access method and falls back to the BIOS if that doesn't
  1562. work. If unsure, go with the default, which is "Any".
  1563. config PCI_GOBIOS
  1564. bool "BIOS"
  1565. config PCI_GOMMCONFIG
  1566. bool "MMConfig"
  1567. config PCI_GODIRECT
  1568. bool "Direct"
  1569. config PCI_GOOLPC
  1570. bool "OLPC XO-1"
  1571. depends on OLPC
  1572. config PCI_GOANY
  1573. bool "Any"
  1574. endchoice
  1575. config PCI_BIOS
  1576. def_bool y
  1577. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1578. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1579. config PCI_DIRECT
  1580. def_bool y
  1581. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1582. config PCI_MMCONFIG
  1583. def_bool y
  1584. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1585. config PCI_OLPC
  1586. def_bool y
  1587. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1588. config PCI_XEN
  1589. def_bool y
  1590. depends on PCI && XEN
  1591. select SWIOTLB_XEN
  1592. config PCI_DOMAINS
  1593. def_bool y
  1594. depends on PCI
  1595. config PCI_MMCONFIG
  1596. bool "Support mmconfig PCI config space access"
  1597. depends on X86_64 && PCI && ACPI
  1598. config PCI_CNB20LE_QUIRK
  1599. bool "Read CNB20LE Host Bridge Windows" if EXPERT
  1600. default n
  1601. depends on PCI && EXPERIMENTAL
  1602. help
  1603. Read the PCI windows out of the CNB20LE host bridge. This allows
  1604. PCI hotplug to work on systems with the CNB20LE chipset which do
  1605. not have ACPI.
  1606. There's no public spec for this chipset, and this functionality
  1607. is known to be incomplete.
  1608. You should say N unless you know you need this.
  1609. config DMAR
  1610. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1611. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1612. help
  1613. DMA remapping (DMAR) devices support enables independent address
  1614. translations for Direct Memory Access (DMA) from devices.
  1615. These DMA remapping devices are reported via ACPI tables
  1616. and include PCI device scope covered by these DMA
  1617. remapping devices.
  1618. config DMAR_DEFAULT_ON
  1619. def_bool y
  1620. prompt "Enable DMA Remapping Devices by default"
  1621. depends on DMAR
  1622. help
  1623. Selecting this option will enable a DMAR device at boot time if
  1624. one is found. If this option is not selected, DMAR support can
  1625. be enabled by passing intel_iommu=on to the kernel. It is
  1626. recommended you say N here while the DMAR code remains
  1627. experimental.
  1628. config DMAR_BROKEN_GFX_WA
  1629. bool "Workaround broken graphics drivers (going away soon)"
  1630. depends on DMAR && BROKEN
  1631. ---help---
  1632. Current Graphics drivers tend to use physical address
  1633. for DMA and avoid using DMA APIs. Setting this config
  1634. option permits the IOMMU driver to set a unity map for
  1635. all the OS-visible memory. Hence the driver can continue
  1636. to use physical addresses for DMA, at least until this
  1637. option is removed in the 2.6.32 kernel.
  1638. config DMAR_FLOPPY_WA
  1639. def_bool y
  1640. depends on DMAR
  1641. ---help---
  1642. Floppy disk drivers are known to bypass DMA API calls
  1643. thereby failing to work when IOMMU is enabled. This
  1644. workaround will setup a 1:1 mapping for the first
  1645. 16MiB to make floppy (an ISA device) work.
  1646. config INTR_REMAP
  1647. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1648. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1649. ---help---
  1650. Supports Interrupt remapping for IO-APIC and MSI devices.
  1651. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1652. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1653. source "drivers/pci/pcie/Kconfig"
  1654. source "drivers/pci/Kconfig"
  1655. # x86_64 have no ISA slots, but can have ISA-style DMA.
  1656. config ISA_DMA_API
  1657. bool "ISA-style DMA support" if (X86_64 && EXPERT)
  1658. default y
  1659. help
  1660. Enables ISA-style DMA support for devices requiring such controllers.
  1661. If unsure, say Y.
  1662. if X86_32
  1663. config ISA
  1664. bool "ISA support"
  1665. ---help---
  1666. Find out whether you have ISA slots on your motherboard. ISA is the
  1667. name of a bus system, i.e. the way the CPU talks to the other stuff
  1668. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1669. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1670. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1671. config EISA
  1672. bool "EISA support"
  1673. depends on ISA
  1674. ---help---
  1675. The Extended Industry Standard Architecture (EISA) bus was
  1676. developed as an open alternative to the IBM MicroChannel bus.
  1677. The EISA bus provided some of the features of the IBM MicroChannel
  1678. bus while maintaining backward compatibility with cards made for
  1679. the older ISA bus. The EISA bus saw limited use between 1988 and
  1680. 1995 when it was made obsolete by the PCI bus.
  1681. Say Y here if you are building a kernel for an EISA-based machine.
  1682. Otherwise, say N.
  1683. source "drivers/eisa/Kconfig"
  1684. config MCA
  1685. bool "MCA support"
  1686. ---help---
  1687. MicroChannel Architecture is found in some IBM PS/2 machines and
  1688. laptops. It is a bus system similar to PCI or ISA. See
  1689. <file:Documentation/mca.txt> (and especially the web page given
  1690. there) before attempting to build an MCA bus kernel.
  1691. source "drivers/mca/Kconfig"
  1692. config SCx200
  1693. tristate "NatSemi SCx200 support"
  1694. ---help---
  1695. This provides basic support for National Semiconductor's
  1696. (now AMD's) Geode processors. The driver probes for the
  1697. PCI-IDs of several on-chip devices, so its a good dependency
  1698. for other scx200_* drivers.
  1699. If compiled as a module, the driver is named scx200.
  1700. config SCx200HR_TIMER
  1701. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1702. depends on SCx200
  1703. default y
  1704. ---help---
  1705. This driver provides a clocksource built upon the on-chip
  1706. 27MHz high-resolution timer. Its also a workaround for
  1707. NSC Geode SC-1100's buggy TSC, which loses time when the
  1708. processor goes idle (as is done by the scheduler). The
  1709. other workaround is idle=poll boot option.
  1710. config OLPC
  1711. bool "One Laptop Per Child support"
  1712. depends on !X86_PAE
  1713. select GPIOLIB
  1714. select OF
  1715. select OF_PROMTREE
  1716. ---help---
  1717. Add support for detecting the unique features of the OLPC
  1718. XO hardware.
  1719. config OLPC_XO1
  1720. tristate "OLPC XO-1 support"
  1721. depends on OLPC && MFD_CS5535
  1722. ---help---
  1723. Add support for non-essential features of the OLPC XO-1 laptop.
  1724. endif # X86_32
  1725. config AMD_NB
  1726. def_bool y
  1727. depends on CPU_SUP_AMD && PCI
  1728. source "drivers/pcmcia/Kconfig"
  1729. source "drivers/pci/hotplug/Kconfig"
  1730. config RAPIDIO
  1731. bool "RapidIO support"
  1732. depends on PCI
  1733. default n
  1734. help
  1735. If you say Y here, the kernel will include drivers and
  1736. infrastructure code to support RapidIO interconnect devices.
  1737. source "drivers/rapidio/Kconfig"
  1738. endmenu
  1739. menu "Executable file formats / Emulations"
  1740. source "fs/Kconfig.binfmt"
  1741. config IA32_EMULATION
  1742. bool "IA32 Emulation"
  1743. depends on X86_64
  1744. select COMPAT_BINFMT_ELF
  1745. ---help---
  1746. Include code to run 32-bit programs under a 64-bit kernel. You should
  1747. likely turn this on, unless you're 100% sure that you don't have any
  1748. 32-bit programs left.
  1749. config IA32_AOUT
  1750. tristate "IA32 a.out support"
  1751. depends on IA32_EMULATION
  1752. ---help---
  1753. Support old a.out binaries in the 32bit emulation.
  1754. config COMPAT
  1755. def_bool y
  1756. depends on IA32_EMULATION
  1757. config COMPAT_FOR_U64_ALIGNMENT
  1758. def_bool COMPAT
  1759. depends on X86_64
  1760. config SYSVIPC_COMPAT
  1761. def_bool y
  1762. depends on COMPAT && SYSVIPC
  1763. config KEYS_COMPAT
  1764. bool
  1765. depends on COMPAT && KEYS
  1766. default y
  1767. endmenu
  1768. config HAVE_ATOMIC_IOMAP
  1769. def_bool y
  1770. depends on X86_32
  1771. config HAVE_TEXT_POKE_SMP
  1772. bool
  1773. select STOP_MACHINE if SMP
  1774. source "net/Kconfig"
  1775. source "drivers/Kconfig"
  1776. source "drivers/firmware/Kconfig"
  1777. source "fs/Kconfig"
  1778. source "arch/x86/Kconfig.debug"
  1779. source "security/Kconfig"
  1780. source "crypto/Kconfig"
  1781. source "arch/x86/kvm/Kconfig"
  1782. source "lib/Kconfig"