Kconfig 68 KB

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  1. # x86 configuration
  2. mainmenu "Linux Kernel Configuration for x86"
  3. # Select 32 or 64 bit
  4. config 64BIT
  5. bool "64-bit kernel" if ARCH = "x86"
  6. default ARCH = "x86_64"
  7. ---help---
  8. Say yes to build a 64-bit kernel - formerly known as x86_64
  9. Say no to build a 32-bit kernel - formerly known as i386
  10. config X86_32
  11. def_bool !64BIT
  12. config X86_64
  13. def_bool 64BIT
  14. ### Arch settings
  15. config X86
  16. def_bool y
  17. select HAVE_AOUT if X86_32
  18. select HAVE_READQ
  19. select HAVE_WRITEQ
  20. select HAVE_UNSTABLE_SCHED_CLOCK
  21. select HAVE_IDE
  22. select HAVE_OPROFILE
  23. select HAVE_PERF_EVENTS if (!M386 && !M486)
  24. select HAVE_IOREMAP_PROT
  25. select HAVE_KPROBES
  26. select ARCH_WANT_OPTIONAL_GPIOLIB
  27. select ARCH_WANT_FRAME_POINTERS
  28. select HAVE_DMA_ATTRS
  29. select HAVE_KRETPROBES
  30. select HAVE_OPTPROBES
  31. select HAVE_FTRACE_MCOUNT_RECORD
  32. select HAVE_DYNAMIC_FTRACE
  33. select HAVE_FUNCTION_TRACER
  34. select HAVE_FUNCTION_GRAPH_TRACER
  35. select HAVE_FUNCTION_GRAPH_FP_TEST
  36. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  37. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  38. select HAVE_SYSCALL_TRACEPOINTS
  39. select HAVE_KVM
  40. select HAVE_ARCH_KGDB
  41. select HAVE_ARCH_TRACEHOOK
  42. select HAVE_GENERIC_DMA_COHERENT if X86_32
  43. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  44. select USER_STACKTRACE_SUPPORT
  45. select HAVE_REGS_AND_STACK_ACCESS_API
  46. select HAVE_DMA_API_DEBUG
  47. select HAVE_KERNEL_GZIP
  48. select HAVE_KERNEL_BZIP2
  49. select HAVE_KERNEL_LZMA
  50. select HAVE_KERNEL_LZO
  51. select HAVE_HW_BREAKPOINT
  52. select HAVE_MIXED_BREAKPOINTS_REGS
  53. select PERF_EVENTS
  54. select HAVE_PERF_EVENTS_NMI
  55. select ANON_INODES
  56. select HAVE_ARCH_KMEMCHECK
  57. select HAVE_USER_RETURN_NOTIFIER
  58. config INSTRUCTION_DECODER
  59. def_bool (KPROBES || PERF_EVENTS)
  60. config OUTPUT_FORMAT
  61. string
  62. default "elf32-i386" if X86_32
  63. default "elf64-x86-64" if X86_64
  64. config ARCH_DEFCONFIG
  65. string
  66. default "arch/x86/configs/i386_defconfig" if X86_32
  67. default "arch/x86/configs/x86_64_defconfig" if X86_64
  68. config GENERIC_CMOS_UPDATE
  69. def_bool y
  70. config CLOCKSOURCE_WATCHDOG
  71. def_bool y
  72. config GENERIC_CLOCKEVENTS
  73. def_bool y
  74. config GENERIC_CLOCKEVENTS_BROADCAST
  75. def_bool y
  76. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  77. config LOCKDEP_SUPPORT
  78. def_bool y
  79. config STACKTRACE_SUPPORT
  80. def_bool y
  81. config HAVE_LATENCYTOP_SUPPORT
  82. def_bool y
  83. config MMU
  84. def_bool y
  85. config ZONE_DMA
  86. def_bool y
  87. config SBUS
  88. bool
  89. config NEED_DMA_MAP_STATE
  90. def_bool (X86_64 || DMAR || DMA_API_DEBUG)
  91. config NEED_SG_DMA_LENGTH
  92. def_bool y
  93. config GENERIC_ISA_DMA
  94. def_bool y
  95. config GENERIC_IOMAP
  96. def_bool y
  97. config GENERIC_BUG
  98. def_bool y
  99. depends on BUG
  100. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  101. config GENERIC_BUG_RELATIVE_POINTERS
  102. bool
  103. config GENERIC_HWEIGHT
  104. def_bool y
  105. config GENERIC_GPIO
  106. bool
  107. config ARCH_MAY_HAVE_PC_FDC
  108. def_bool y
  109. config RWSEM_GENERIC_SPINLOCK
  110. def_bool !X86_XADD
  111. config RWSEM_XCHGADD_ALGORITHM
  112. def_bool X86_XADD
  113. config ARCH_HAS_CPU_IDLE_WAIT
  114. def_bool y
  115. config GENERIC_CALIBRATE_DELAY
  116. def_bool y
  117. config GENERIC_TIME_VSYSCALL
  118. bool
  119. default X86_64
  120. config ARCH_HAS_CPU_RELAX
  121. def_bool y
  122. config ARCH_HAS_DEFAULT_IDLE
  123. def_bool y
  124. config ARCH_HAS_CACHE_LINE_SIZE
  125. def_bool y
  126. config HAVE_SETUP_PER_CPU_AREA
  127. def_bool y
  128. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  129. def_bool y
  130. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  131. def_bool y
  132. config HAVE_CPUMASK_OF_CPU_MAP
  133. def_bool X86_64_SMP
  134. config ARCH_HIBERNATION_POSSIBLE
  135. def_bool y
  136. config ARCH_SUSPEND_POSSIBLE
  137. def_bool y
  138. config ZONE_DMA32
  139. bool
  140. default X86_64
  141. config ARCH_POPULATES_NODE_MAP
  142. def_bool y
  143. config AUDIT_ARCH
  144. bool
  145. default X86_64
  146. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  147. def_bool y
  148. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  149. def_bool y
  150. config HAVE_EARLY_RES
  151. def_bool y
  152. config HAVE_INTEL_TXT
  153. def_bool y
  154. depends on EXPERIMENTAL && DMAR && ACPI
  155. # Use the generic interrupt handling code in kernel/irq/:
  156. config GENERIC_HARDIRQS
  157. def_bool y
  158. config GENERIC_HARDIRQS_NO__DO_IRQ
  159. def_bool y
  160. config GENERIC_IRQ_PROBE
  161. def_bool y
  162. config GENERIC_PENDING_IRQ
  163. def_bool y
  164. depends on GENERIC_HARDIRQS && SMP
  165. config USE_GENERIC_SMP_HELPERS
  166. def_bool y
  167. depends on SMP
  168. config X86_32_SMP
  169. def_bool y
  170. depends on X86_32 && SMP
  171. config X86_64_SMP
  172. def_bool y
  173. depends on X86_64 && SMP
  174. config X86_HT
  175. def_bool y
  176. depends on SMP
  177. config X86_TRAMPOLINE
  178. def_bool y
  179. depends on SMP || (64BIT && ACPI_SLEEP)
  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 SPARSE_IRQ
  227. bool "Support sparse irq numbering"
  228. depends on PCI_MSI || HT_IRQ
  229. ---help---
  230. This enables support for sparse irqs. This is useful for distro
  231. kernels that want to define a high CONFIG_NR_CPUS value but still
  232. want to have low kernel memory footprint on smaller machines.
  233. ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
  234. out the irq_desc[] array in a more NUMA-friendly way. )
  235. If you don't know what to do here, say N.
  236. config NUMA_IRQ_DESC
  237. def_bool y
  238. depends on SPARSE_IRQ && NUMA
  239. config X86_MPPARSE
  240. bool "Enable MPS table" if ACPI
  241. default y
  242. depends on X86_LOCAL_APIC
  243. ---help---
  244. For old smp systems that do not have proper acpi support. Newer systems
  245. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  246. config X86_BIGSMP
  247. bool "Support for big SMP systems with more than 8 CPUs"
  248. depends on X86_32 && SMP
  249. ---help---
  250. This option is needed for the systems that have more than 8 CPUs
  251. if X86_32
  252. config X86_EXTENDED_PLATFORM
  253. bool "Support for extended (non-PC) x86 platforms"
  254. default y
  255. ---help---
  256. If you disable this option then the kernel will only support
  257. standard PC platforms. (which covers the vast majority of
  258. systems out there.)
  259. If you enable this option then you'll be able to select support
  260. for the following (non-PC) 32 bit x86 platforms:
  261. AMD Elan
  262. NUMAQ (IBM/Sequent)
  263. RDC R-321x SoC
  264. SGI 320/540 (Visual Workstation)
  265. Summit/EXA (IBM x440)
  266. Unisys ES7000 IA32 series
  267. Moorestown MID devices
  268. If you have one of these systems, or if you want to build a
  269. generic distribution kernel, say Y here - otherwise say N.
  270. endif
  271. if X86_64
  272. config X86_EXTENDED_PLATFORM
  273. bool "Support for extended (non-PC) x86 platforms"
  274. default y
  275. ---help---
  276. If you disable this option then the kernel will only support
  277. standard PC platforms. (which covers the vast majority of
  278. systems out there.)
  279. If you enable this option then you'll be able to select support
  280. for the following (non-PC) 64 bit x86 platforms:
  281. ScaleMP vSMP
  282. SGI Ultraviolet
  283. If you have one of these systems, or if you want to build a
  284. generic distribution kernel, say Y here - otherwise say N.
  285. endif
  286. # This is an alphabetically sorted list of 64 bit extended platforms
  287. # Please maintain the alphabetic order if and when there are additions
  288. config X86_VSMP
  289. bool "ScaleMP vSMP"
  290. select PARAVIRT
  291. depends on X86_64 && PCI
  292. depends on X86_EXTENDED_PLATFORM
  293. ---help---
  294. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  295. supposed to run on these EM64T-based machines. Only choose this option
  296. if you have one of these machines.
  297. config X86_UV
  298. bool "SGI Ultraviolet"
  299. depends on X86_64
  300. depends on X86_EXTENDED_PLATFORM
  301. depends on NUMA
  302. depends on X86_X2APIC
  303. ---help---
  304. This option is needed in order to support SGI Ultraviolet systems.
  305. If you don't have one of these, you should say N here.
  306. # Following is an alphabetically sorted list of 32 bit extended platforms
  307. # Please maintain the alphabetic order if and when there are additions
  308. config X86_ELAN
  309. bool "AMD Elan"
  310. depends on X86_32
  311. depends on X86_EXTENDED_PLATFORM
  312. ---help---
  313. Select this for an AMD Elan processor.
  314. Do not use this option for K6/Athlon/Opteron processors!
  315. If unsure, choose "PC-compatible" instead.
  316. config X86_MRST
  317. bool "Moorestown MID platform"
  318. depends on PCI
  319. depends on PCI_GOANY
  320. depends on X86_32
  321. depends on X86_EXTENDED_PLATFORM
  322. depends on X86_IO_APIC
  323. select APB_TIMER
  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 SCHED_OMIT_FRAME_POINTER
  395. def_bool y
  396. prompt "Single-depth WCHAN output"
  397. depends on X86
  398. ---help---
  399. Calculate simpler /proc/<PID>/wchan values. If this option
  400. is disabled then wchan values will recurse back to the
  401. caller function. This provides more accurate wchan values,
  402. at the expense of slightly more scheduling overhead.
  403. If in doubt, say "Y".
  404. menuconfig PARAVIRT_GUEST
  405. bool "Paravirtualized guest support"
  406. ---help---
  407. Say Y here to get to see options related to running Linux under
  408. various hypervisors. This option alone does not add any kernel code.
  409. If you say N, all options in this submenu will be skipped and disabled.
  410. if PARAVIRT_GUEST
  411. source "arch/x86/xen/Kconfig"
  412. config KVM_CLOCK
  413. bool "KVM paravirtualized clock"
  414. select PARAVIRT
  415. select PARAVIRT_CLOCK
  416. ---help---
  417. Turning on this option will allow you to run a paravirtualized clock
  418. when running over the KVM hypervisor. Instead of relying on a PIT
  419. (or probably other) emulation by the underlying device model, the host
  420. provides the guest with timing infrastructure such as time of day, and
  421. system time
  422. config KVM_GUEST
  423. bool "KVM Guest support"
  424. select PARAVIRT
  425. ---help---
  426. This option enables various optimizations for running under the KVM
  427. hypervisor.
  428. source "arch/x86/lguest/Kconfig"
  429. config PARAVIRT
  430. bool "Enable paravirtualization code"
  431. ---help---
  432. This changes the kernel so it can modify itself when it is run
  433. under a hypervisor, potentially improving performance significantly
  434. over full virtualization. However, when run without a hypervisor
  435. the kernel is theoretically slower and slightly larger.
  436. config PARAVIRT_SPINLOCKS
  437. bool "Paravirtualization layer for spinlocks"
  438. depends on PARAVIRT && SMP && EXPERIMENTAL
  439. ---help---
  440. Paravirtualized spinlocks allow a pvops backend to replace the
  441. spinlock implementation with something virtualization-friendly
  442. (for example, block the virtual CPU rather than spinning).
  443. Unfortunately the downside is an up to 5% performance hit on
  444. native kernels, with various workloads.
  445. If you are unsure how to answer this question, answer N.
  446. config PARAVIRT_CLOCK
  447. bool
  448. endif
  449. config PARAVIRT_DEBUG
  450. bool "paravirt-ops debugging"
  451. depends on PARAVIRT && DEBUG_KERNEL
  452. ---help---
  453. Enable to debug paravirt_ops internals. Specifically, BUG if
  454. a paravirt_op is missing when it is called.
  455. config NO_BOOTMEM
  456. default y
  457. bool "Disable Bootmem code"
  458. ---help---
  459. Use early_res directly instead of bootmem before slab is ready.
  460. - allocator (buddy) [generic]
  461. - early allocator (bootmem) [generic]
  462. - very early allocator (reserve_early*()) [x86]
  463. - very very early allocator (early brk model) [x86]
  464. So reduce one layer between early allocator to final allocator
  465. config MEMTEST
  466. bool "Memtest"
  467. ---help---
  468. This option adds a kernel parameter 'memtest', which allows memtest
  469. to be set.
  470. memtest=0, mean disabled; -- default
  471. memtest=1, mean do 1 test pattern;
  472. ...
  473. memtest=4, mean do 4 test patterns.
  474. If you are unsure how to answer this question, answer N.
  475. config X86_SUMMIT_NUMA
  476. def_bool y
  477. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  478. config X86_CYCLONE_TIMER
  479. def_bool y
  480. depends on X86_32_NON_STANDARD
  481. source "arch/x86/Kconfig.cpu"
  482. config HPET_TIMER
  483. def_bool X86_64
  484. prompt "HPET Timer Support" if X86_32
  485. ---help---
  486. Use the IA-PC HPET (High Precision Event Timer) to manage
  487. time in preference to the PIT and RTC, if a HPET is
  488. present.
  489. HPET is the next generation timer replacing legacy 8254s.
  490. The HPET provides a stable time base on SMP
  491. systems, unlike the TSC, but it is more expensive to access,
  492. as it is off-chip. You can find the HPET spec at
  493. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  494. You can safely choose Y here. However, HPET will only be
  495. activated if the platform and the BIOS support this feature.
  496. Otherwise the 8254 will be used for timing services.
  497. Choose N to continue using the legacy 8254 timer.
  498. config HPET_EMULATE_RTC
  499. def_bool y
  500. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  501. config APB_TIMER
  502. def_bool y if MRST
  503. prompt "Langwell APB Timer Support" if X86_MRST
  504. help
  505. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  506. The APBT provides a stable time base on SMP
  507. systems, unlike the TSC, but it is more expensive to access,
  508. as it is off-chip. APB timers are always running regardless of CPU
  509. C states, they are used as per CPU clockevent device when possible.
  510. # Mark as embedded because too many people got it wrong.
  511. # The code disables itself when not needed.
  512. config DMI
  513. default y
  514. bool "Enable DMI scanning" if EMBEDDED
  515. ---help---
  516. Enabled scanning of DMI to identify machine quirks. Say Y
  517. here unless you have verified that your setup is not
  518. affected by entries in the DMI blacklist. Required by PNP
  519. BIOS code.
  520. config GART_IOMMU
  521. bool "GART IOMMU support" if EMBEDDED
  522. default y
  523. select SWIOTLB
  524. depends on X86_64 && PCI && K8_NB
  525. ---help---
  526. Support for full DMA access of devices with 32bit memory access only
  527. on systems with more than 3GB. This is usually needed for USB,
  528. sound, many IDE/SATA chipsets and some other devices.
  529. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  530. based hardware IOMMU and a software bounce buffer based IOMMU used
  531. on Intel systems and as fallback.
  532. The code is only active when needed (enough memory and limited
  533. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  534. too.
  535. config CALGARY_IOMMU
  536. bool "IBM Calgary IOMMU support"
  537. select SWIOTLB
  538. depends on X86_64 && PCI && EXPERIMENTAL
  539. ---help---
  540. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  541. systems. Needed to run systems with more than 3GB of memory
  542. properly with 32-bit PCI devices that do not support DAC
  543. (Double Address Cycle). Calgary also supports bus level
  544. isolation, where all DMAs pass through the IOMMU. This
  545. prevents them from going anywhere except their intended
  546. destination. This catches hard-to-find kernel bugs and
  547. mis-behaving drivers and devices that do not use the DMA-API
  548. properly to set up their DMA buffers. The IOMMU can be
  549. turned off at boot time with the iommu=off parameter.
  550. Normally the kernel will make the right choice by itself.
  551. If unsure, say Y.
  552. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  553. def_bool y
  554. prompt "Should Calgary be enabled by default?"
  555. depends on CALGARY_IOMMU
  556. ---help---
  557. Should Calgary be enabled by default? if you choose 'y', Calgary
  558. will be used (if it exists). If you choose 'n', Calgary will not be
  559. used even if it exists. If you choose 'n' and would like to use
  560. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  561. If unsure, say Y.
  562. config AMD_IOMMU
  563. bool "AMD IOMMU support"
  564. select SWIOTLB
  565. select PCI_MSI
  566. depends on X86_64 && PCI && ACPI
  567. ---help---
  568. With this option you can enable support for AMD IOMMU hardware in
  569. your system. An IOMMU is a hardware component which provides
  570. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  571. can isolate the the DMA memory of different devices and protect the
  572. system from misbehaving device drivers or hardware.
  573. You can find out if your system has an AMD IOMMU if you look into
  574. your BIOS for an option to enable it or if you have an IVRS ACPI
  575. table.
  576. config AMD_IOMMU_STATS
  577. bool "Export AMD IOMMU statistics to debugfs"
  578. depends on AMD_IOMMU
  579. select DEBUG_FS
  580. ---help---
  581. This option enables code in the AMD IOMMU driver to collect various
  582. statistics about whats happening in the driver and exports that
  583. information to userspace via debugfs.
  584. If unsure, say N.
  585. # need this always selected by IOMMU for the VIA workaround
  586. config SWIOTLB
  587. def_bool y if X86_64
  588. ---help---
  589. Support for software bounce buffers used on x86-64 systems
  590. which don't have a hardware IOMMU (e.g. the current generation
  591. of Intel's x86-64 CPUs). Using this PCI devices which can only
  592. access 32-bits of memory can be used on systems with more than
  593. 3 GB of memory. If unsure, say Y.
  594. config IOMMU_HELPER
  595. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  596. config IOMMU_API
  597. def_bool (AMD_IOMMU || DMAR)
  598. config MAXSMP
  599. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  600. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  601. select CPUMASK_OFFSTACK
  602. ---help---
  603. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  604. If unsure, say N.
  605. config NR_CPUS
  606. int "Maximum number of CPUs" if SMP && !MAXSMP
  607. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  608. range 2 512 if SMP && !MAXSMP
  609. default "1" if !SMP
  610. default "4096" if MAXSMP
  611. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  612. default "8" if SMP
  613. ---help---
  614. This allows you to specify the maximum number of CPUs which this
  615. kernel will support. The maximum supported value is 512 and the
  616. minimum value which makes sense is 2.
  617. This is purely to save memory - each supported CPU adds
  618. approximately eight kilobytes to the kernel image.
  619. config SCHED_SMT
  620. bool "SMT (Hyperthreading) scheduler support"
  621. depends on X86_HT
  622. ---help---
  623. SMT scheduler support improves the CPU scheduler's decision making
  624. when dealing with Intel Pentium 4 chips with HyperThreading at a
  625. cost of slightly increased overhead in some places. If unsure say
  626. N here.
  627. config SCHED_MC
  628. def_bool y
  629. prompt "Multi-core scheduler support"
  630. depends on X86_HT
  631. ---help---
  632. Multi-core scheduler support improves the CPU scheduler's decision
  633. making when dealing with multi-core CPU chips at a cost of slightly
  634. increased overhead in some places. If unsure say N here.
  635. source "kernel/Kconfig.preempt"
  636. config X86_UP_APIC
  637. bool "Local APIC support on uniprocessors"
  638. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  639. ---help---
  640. A local APIC (Advanced Programmable Interrupt Controller) is an
  641. integrated interrupt controller in the CPU. If you have a single-CPU
  642. system which has a processor with a local APIC, you can say Y here to
  643. enable and use it. If you say Y here even though your machine doesn't
  644. have a local APIC, then the kernel will still run with no slowdown at
  645. all. The local APIC supports CPU-generated self-interrupts (timer,
  646. performance counters), and the NMI watchdog which detects hard
  647. lockups.
  648. config X86_UP_IOAPIC
  649. bool "IO-APIC support on uniprocessors"
  650. depends on X86_UP_APIC
  651. ---help---
  652. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  653. SMP-capable replacement for PC-style interrupt controllers. Most
  654. SMP systems and many recent uniprocessor systems have one.
  655. If you have a single-CPU system with an IO-APIC, you can say Y here
  656. to use it. If you say Y here even though your machine doesn't have
  657. an IO-APIC, then the kernel will still run with no slowdown at all.
  658. config X86_LOCAL_APIC
  659. def_bool y
  660. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  661. config X86_IO_APIC
  662. def_bool y
  663. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  664. config X86_VISWS_APIC
  665. def_bool y
  666. depends on X86_32 && X86_VISWS
  667. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  668. bool "Reroute for broken boot IRQs"
  669. depends on X86_IO_APIC
  670. ---help---
  671. This option enables a workaround that fixes a source of
  672. spurious interrupts. This is recommended when threaded
  673. interrupt handling is used on systems where the generation of
  674. superfluous "boot interrupts" cannot be disabled.
  675. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  676. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  677. kernel does during interrupt handling). On chipsets where this
  678. boot IRQ generation cannot be disabled, this workaround keeps
  679. the original IRQ line masked so that only the equivalent "boot
  680. IRQ" is delivered to the CPUs. The workaround also tells the
  681. kernel to set up the IRQ handler on the boot IRQ line. In this
  682. way only one interrupt is delivered to the kernel. Otherwise
  683. the spurious second interrupt may cause the kernel to bring
  684. down (vital) interrupt lines.
  685. Only affects "broken" chipsets. Interrupt sharing may be
  686. increased on these systems.
  687. config X86_MCE
  688. bool "Machine Check / overheating reporting"
  689. ---help---
  690. Machine Check support allows the processor to notify the
  691. kernel if it detects a problem (e.g. overheating, data corruption).
  692. The action the kernel takes depends on the severity of the problem,
  693. ranging from warning messages to halting the machine.
  694. config X86_MCE_INTEL
  695. def_bool y
  696. prompt "Intel MCE features"
  697. depends on X86_MCE && X86_LOCAL_APIC
  698. ---help---
  699. Additional support for intel specific MCE features such as
  700. the thermal monitor.
  701. config X86_MCE_AMD
  702. def_bool y
  703. prompt "AMD MCE features"
  704. depends on X86_MCE && X86_LOCAL_APIC
  705. ---help---
  706. Additional support for AMD specific MCE features such as
  707. the DRAM Error Threshold.
  708. config X86_ANCIENT_MCE
  709. bool "Support for old Pentium 5 / WinChip machine checks"
  710. depends on X86_32 && X86_MCE
  711. ---help---
  712. Include support for machine check handling on old Pentium 5 or WinChip
  713. systems. These typically need to be enabled explicitely on the command
  714. line.
  715. config X86_MCE_THRESHOLD
  716. depends on X86_MCE_AMD || X86_MCE_INTEL
  717. def_bool y
  718. config X86_MCE_INJECT
  719. depends on X86_MCE
  720. tristate "Machine check injector support"
  721. ---help---
  722. Provide support for injecting machine checks for testing purposes.
  723. If you don't know what a machine check is and you don't do kernel
  724. QA it is safe to say n.
  725. config X86_THERMAL_VECTOR
  726. def_bool y
  727. depends on X86_MCE_INTEL
  728. config VM86
  729. bool "Enable VM86 support" if EMBEDDED
  730. default y
  731. depends on X86_32
  732. ---help---
  733. This option is required by programs like DOSEMU to run 16-bit legacy
  734. code on X86 processors. It also may be needed by software like
  735. XFree86 to initialize some video cards via BIOS. Disabling this
  736. option saves about 6k.
  737. config TOSHIBA
  738. tristate "Toshiba Laptop support"
  739. depends on X86_32
  740. ---help---
  741. This adds a driver to safely access the System Management Mode of
  742. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  743. not work on models with a Phoenix BIOS. The System Management Mode
  744. is used to set the BIOS and power saving options on Toshiba portables.
  745. For information on utilities to make use of this driver see the
  746. Toshiba Linux utilities web site at:
  747. <http://www.buzzard.org.uk/toshiba/>.
  748. Say Y if you intend to run this kernel on a Toshiba portable.
  749. Say N otherwise.
  750. config I8K
  751. tristate "Dell laptop support"
  752. ---help---
  753. This adds a driver to safely access the System Management Mode
  754. of the CPU on the Dell Inspiron 8000. The System Management Mode
  755. is used to read cpu temperature and cooling fan status and to
  756. control the fans on the I8K portables.
  757. This driver has been tested only on the Inspiron 8000 but it may
  758. also work with other Dell laptops. You can force loading on other
  759. models by passing the parameter `force=1' to the module. Use at
  760. your own risk.
  761. For information on utilities to make use of this driver see the
  762. I8K Linux utilities web site at:
  763. <http://people.debian.org/~dz/i8k/>
  764. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  765. Say N otherwise.
  766. config X86_REBOOTFIXUPS
  767. bool "Enable X86 board specific fixups for reboot"
  768. depends on X86_32
  769. ---help---
  770. This enables chipset and/or board specific fixups to be done
  771. in order to get reboot to work correctly. This is only needed on
  772. some combinations of hardware and BIOS. The symptom, for which
  773. this config is intended, is when reboot ends with a stalled/hung
  774. system.
  775. Currently, the only fixup is for the Geode machines using
  776. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  777. Say Y if you want to enable the fixup. Currently, it's safe to
  778. enable this option even if you don't need it.
  779. Say N otherwise.
  780. config MICROCODE
  781. tristate "/dev/cpu/microcode - microcode support"
  782. select FW_LOADER
  783. ---help---
  784. If you say Y here, you will be able to update the microcode on
  785. certain Intel and AMD processors. The Intel support is for the
  786. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  787. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  788. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  789. You will obviously need the actual microcode binary data itself
  790. which is not shipped with the Linux kernel.
  791. This option selects the general module only, you need to select
  792. at least one vendor specific module as well.
  793. To compile this driver as a module, choose M here: the
  794. module will be called microcode.
  795. config MICROCODE_INTEL
  796. bool "Intel microcode patch loading support"
  797. depends on MICROCODE
  798. default MICROCODE
  799. select FW_LOADER
  800. ---help---
  801. This options enables microcode patch loading support for Intel
  802. processors.
  803. For latest news and information on obtaining all the required
  804. Intel ingredients for this driver, check:
  805. <http://www.urbanmyth.org/microcode/>.
  806. config MICROCODE_AMD
  807. bool "AMD microcode patch loading support"
  808. depends on MICROCODE
  809. select FW_LOADER
  810. ---help---
  811. If you select this option, microcode patch loading support for AMD
  812. processors will be enabled.
  813. config MICROCODE_OLD_INTERFACE
  814. def_bool y
  815. depends on MICROCODE
  816. config X86_MSR
  817. tristate "/dev/cpu/*/msr - Model-specific register support"
  818. ---help---
  819. This device gives privileged processes access to the x86
  820. Model-Specific Registers (MSRs). It is a character device with
  821. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  822. MSR accesses are directed to a specific CPU on multi-processor
  823. systems.
  824. config X86_CPUID
  825. tristate "/dev/cpu/*/cpuid - CPU information support"
  826. ---help---
  827. This device gives processes access to the x86 CPUID instruction to
  828. be executed on a specific processor. It is a character device
  829. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  830. /dev/cpu/31/cpuid.
  831. choice
  832. prompt "High Memory Support"
  833. default HIGHMEM64G if X86_NUMAQ
  834. default HIGHMEM4G
  835. depends on X86_32
  836. config NOHIGHMEM
  837. bool "off"
  838. depends on !X86_NUMAQ
  839. ---help---
  840. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  841. However, the address space of 32-bit x86 processors is only 4
  842. Gigabytes large. That means that, if you have a large amount of
  843. physical memory, not all of it can be "permanently mapped" by the
  844. kernel. The physical memory that's not permanently mapped is called
  845. "high memory".
  846. If you are compiling a kernel which will never run on a machine with
  847. more than 1 Gigabyte total physical RAM, answer "off" here (default
  848. choice and suitable for most users). This will result in a "3GB/1GB"
  849. split: 3GB are mapped so that each process sees a 3GB virtual memory
  850. space and the remaining part of the 4GB virtual memory space is used
  851. by the kernel to permanently map as much physical memory as
  852. possible.
  853. If the machine has between 1 and 4 Gigabytes physical RAM, then
  854. answer "4GB" here.
  855. If more than 4 Gigabytes is used then answer "64GB" here. This
  856. selection turns Intel PAE (Physical Address Extension) mode on.
  857. PAE implements 3-level paging on IA32 processors. PAE is fully
  858. supported by Linux, PAE mode is implemented on all recent Intel
  859. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  860. then the kernel will not boot on CPUs that don't support PAE!
  861. The actual amount of total physical memory will either be
  862. auto detected or can be forced by using a kernel command line option
  863. such as "mem=256M". (Try "man bootparam" or see the documentation of
  864. your boot loader (lilo or loadlin) about how to pass options to the
  865. kernel at boot time.)
  866. If unsure, say "off".
  867. config HIGHMEM4G
  868. bool "4GB"
  869. depends on !X86_NUMAQ
  870. ---help---
  871. Select this if you have a 32-bit processor and between 1 and 4
  872. gigabytes of physical RAM.
  873. config HIGHMEM64G
  874. bool "64GB"
  875. depends on !M386 && !M486
  876. select X86_PAE
  877. ---help---
  878. Select this if you have a 32-bit processor and more than 4
  879. gigabytes of physical RAM.
  880. endchoice
  881. choice
  882. depends on EXPERIMENTAL
  883. prompt "Memory split" if EMBEDDED
  884. default VMSPLIT_3G
  885. depends on X86_32
  886. ---help---
  887. Select the desired split between kernel and user memory.
  888. If the address range available to the kernel is less than the
  889. physical memory installed, the remaining memory will be available
  890. as "high memory". Accessing high memory is a little more costly
  891. than low memory, as it needs to be mapped into the kernel first.
  892. Note that increasing the kernel address space limits the range
  893. available to user programs, making the address space there
  894. tighter. Selecting anything other than the default 3G/1G split
  895. will also likely make your kernel incompatible with binary-only
  896. kernel modules.
  897. If you are not absolutely sure what you are doing, leave this
  898. option alone!
  899. config VMSPLIT_3G
  900. bool "3G/1G user/kernel split"
  901. config VMSPLIT_3G_OPT
  902. depends on !X86_PAE
  903. bool "3G/1G user/kernel split (for full 1G low memory)"
  904. config VMSPLIT_2G
  905. bool "2G/2G user/kernel split"
  906. config VMSPLIT_2G_OPT
  907. depends on !X86_PAE
  908. bool "2G/2G user/kernel split (for full 2G low memory)"
  909. config VMSPLIT_1G
  910. bool "1G/3G user/kernel split"
  911. endchoice
  912. config PAGE_OFFSET
  913. hex
  914. default 0xB0000000 if VMSPLIT_3G_OPT
  915. default 0x80000000 if VMSPLIT_2G
  916. default 0x78000000 if VMSPLIT_2G_OPT
  917. default 0x40000000 if VMSPLIT_1G
  918. default 0xC0000000
  919. depends on X86_32
  920. config HIGHMEM
  921. def_bool y
  922. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  923. config X86_PAE
  924. bool "PAE (Physical Address Extension) Support"
  925. depends on X86_32 && !HIGHMEM4G
  926. ---help---
  927. PAE is required for NX support, and furthermore enables
  928. larger swapspace support for non-overcommit purposes. It
  929. has the cost of more pagetable lookup overhead, and also
  930. consumes more pagetable space per process.
  931. config ARCH_PHYS_ADDR_T_64BIT
  932. def_bool X86_64 || X86_PAE
  933. config DIRECT_GBPAGES
  934. bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
  935. default y
  936. depends on X86_64
  937. ---help---
  938. Allow the kernel linear mapping to use 1GB pages on CPUs that
  939. support it. This can improve the kernel's performance a tiny bit by
  940. reducing TLB pressure. If in doubt, say "Y".
  941. # Common NUMA Features
  942. config NUMA
  943. bool "Numa Memory Allocation and Scheduler Support"
  944. depends on SMP
  945. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  946. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  947. ---help---
  948. Enable NUMA (Non Uniform Memory Access) support.
  949. The kernel will try to allocate memory used by a CPU on the
  950. local memory controller of the CPU and add some more
  951. NUMA awareness to the kernel.
  952. For 64-bit this is recommended if the system is Intel Core i7
  953. (or later), AMD Opteron, or EM64T NUMA.
  954. For 32-bit this is only needed on (rare) 32-bit-only platforms
  955. that support NUMA topologies, such as NUMAQ / Summit, or if you
  956. boot a 32-bit kernel on a 64-bit NUMA platform.
  957. Otherwise, you should say N.
  958. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  959. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  960. config K8_NUMA
  961. def_bool y
  962. prompt "Old style AMD Opteron NUMA detection"
  963. depends on X86_64 && NUMA && PCI
  964. ---help---
  965. Enable K8 NUMA node topology detection. You should say Y here if
  966. you have a multi processor AMD K8 system. This uses an old
  967. method to read the NUMA configuration directly from the builtin
  968. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  969. instead, which also takes priority if both are compiled in.
  970. config X86_64_ACPI_NUMA
  971. def_bool y
  972. prompt "ACPI NUMA detection"
  973. depends on X86_64 && NUMA && ACPI && PCI
  974. select ACPI_NUMA
  975. ---help---
  976. Enable ACPI SRAT based node topology detection.
  977. # Some NUMA nodes have memory ranges that span
  978. # other nodes. Even though a pfn is valid and
  979. # between a node's start and end pfns, it may not
  980. # reside on that node. See memmap_init_zone()
  981. # for details.
  982. config NODES_SPAN_OTHER_NODES
  983. def_bool y
  984. depends on X86_64_ACPI_NUMA
  985. config NUMA_EMU
  986. bool "NUMA emulation"
  987. depends on X86_64 && NUMA
  988. ---help---
  989. Enable NUMA emulation. A flat machine will be split
  990. into virtual nodes when booted with "numa=fake=N", where N is the
  991. number of nodes. This is only useful for debugging.
  992. config NODES_SHIFT
  993. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  994. range 1 10
  995. default "10" if MAXSMP
  996. default "6" if X86_64
  997. default "4" if X86_NUMAQ
  998. default "3"
  999. depends on NEED_MULTIPLE_NODES
  1000. ---help---
  1001. Specify the maximum number of NUMA Nodes available on the target
  1002. system. Increases memory reserved to accommodate various tables.
  1003. config HAVE_ARCH_BOOTMEM
  1004. def_bool y
  1005. depends on X86_32 && NUMA
  1006. config ARCH_HAVE_MEMORY_PRESENT
  1007. def_bool y
  1008. depends on X86_32 && DISCONTIGMEM
  1009. config NEED_NODE_MEMMAP_SIZE
  1010. def_bool y
  1011. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1012. config HAVE_ARCH_ALLOC_REMAP
  1013. def_bool y
  1014. depends on X86_32 && NUMA
  1015. config ARCH_FLATMEM_ENABLE
  1016. def_bool y
  1017. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
  1018. config ARCH_DISCONTIGMEM_ENABLE
  1019. def_bool y
  1020. depends on NUMA && X86_32
  1021. config ARCH_DISCONTIGMEM_DEFAULT
  1022. def_bool y
  1023. depends on NUMA && X86_32
  1024. config ARCH_PROC_KCORE_TEXT
  1025. def_bool y
  1026. depends on X86_64 && PROC_KCORE
  1027. config ARCH_SPARSEMEM_DEFAULT
  1028. def_bool y
  1029. depends on X86_64
  1030. config ARCH_SPARSEMEM_ENABLE
  1031. def_bool y
  1032. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1033. select SPARSEMEM_STATIC if X86_32
  1034. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1035. config ARCH_SELECT_MEMORY_MODEL
  1036. def_bool y
  1037. depends on ARCH_SPARSEMEM_ENABLE
  1038. config ARCH_MEMORY_PROBE
  1039. def_bool X86_64
  1040. depends on MEMORY_HOTPLUG
  1041. config ILLEGAL_POINTER_VALUE
  1042. hex
  1043. default 0 if X86_32
  1044. default 0xdead000000000000 if X86_64
  1045. source "mm/Kconfig"
  1046. config HIGHPTE
  1047. bool "Allocate 3rd-level pagetables from highmem"
  1048. depends on HIGHMEM
  1049. ---help---
  1050. The VM uses one page table entry for each page of physical memory.
  1051. For systems with a lot of RAM, this can be wasteful of precious
  1052. low memory. Setting this option will put user-space page table
  1053. entries in high memory.
  1054. config X86_CHECK_BIOS_CORRUPTION
  1055. bool "Check for low memory corruption"
  1056. ---help---
  1057. Periodically check for memory corruption in low memory, which
  1058. is suspected to be caused by BIOS. Even when enabled in the
  1059. configuration, it is disabled at runtime. Enable it by
  1060. setting "memory_corruption_check=1" on the kernel command
  1061. line. By default it scans the low 64k of memory every 60
  1062. seconds; see the memory_corruption_check_size and
  1063. memory_corruption_check_period parameters in
  1064. Documentation/kernel-parameters.txt to adjust this.
  1065. When enabled with the default parameters, this option has
  1066. almost no overhead, as it reserves a relatively small amount
  1067. of memory and scans it infrequently. It both detects corruption
  1068. and prevents it from affecting the running system.
  1069. It is, however, intended as a diagnostic tool; if repeatable
  1070. BIOS-originated corruption always affects the same memory,
  1071. you can use memmap= to prevent the kernel from using that
  1072. memory.
  1073. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1074. bool "Set the default setting of memory_corruption_check"
  1075. depends on X86_CHECK_BIOS_CORRUPTION
  1076. default y
  1077. ---help---
  1078. Set whether the default state of memory_corruption_check is
  1079. on or off.
  1080. config X86_RESERVE_LOW_64K
  1081. bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
  1082. default y
  1083. ---help---
  1084. Reserve the first 64K of physical RAM on BIOSes that are known
  1085. to potentially corrupt that memory range. A numbers of BIOSes are
  1086. known to utilize this area during suspend/resume, so it must not
  1087. be used by the kernel.
  1088. Set this to N if you are absolutely sure that you trust the BIOS
  1089. to get all its memory reservations and usages right.
  1090. If you have doubts about the BIOS (e.g. suspend/resume does not
  1091. work or there's kernel crashes after certain hardware hotplug
  1092. events) and it's not AMI or Phoenix, then you might want to enable
  1093. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
  1094. corruption patterns.
  1095. Say Y if unsure.
  1096. config MATH_EMULATION
  1097. bool
  1098. prompt "Math emulation" if X86_32
  1099. ---help---
  1100. Linux can emulate a math coprocessor (used for floating point
  1101. operations) if you don't have one. 486DX and Pentium processors have
  1102. a math coprocessor built in, 486SX and 386 do not, unless you added
  1103. a 487DX or 387, respectively. (The messages during boot time can
  1104. give you some hints here ["man dmesg"].) Everyone needs either a
  1105. coprocessor or this emulation.
  1106. If you don't have a math coprocessor, you need to say Y here; if you
  1107. say Y here even though you have a coprocessor, the coprocessor will
  1108. be used nevertheless. (This behavior can be changed with the kernel
  1109. command line option "no387", which comes handy if your coprocessor
  1110. is broken. Try "man bootparam" or see the documentation of your boot
  1111. loader (lilo or loadlin) about how to pass options to the kernel at
  1112. boot time.) This means that it is a good idea to say Y here if you
  1113. intend to use this kernel on different machines.
  1114. More information about the internals of the Linux math coprocessor
  1115. emulation can be found in <file:arch/x86/math-emu/README>.
  1116. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1117. kernel, it won't hurt.
  1118. config MTRR
  1119. def_bool y
  1120. prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
  1121. ---help---
  1122. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1123. the Memory Type Range Registers (MTRRs) may be used to control
  1124. processor access to memory ranges. This is most useful if you have
  1125. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1126. allows bus write transfers to be combined into a larger transfer
  1127. before bursting over the PCI/AGP bus. This can increase performance
  1128. of image write operations 2.5 times or more. Saying Y here creates a
  1129. /proc/mtrr file which may be used to manipulate your processor's
  1130. MTRRs. Typically the X server should use this.
  1131. This code has a reasonably generic interface so that similar
  1132. control registers on other processors can be easily supported
  1133. as well:
  1134. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1135. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1136. these, the ARRs are used to emulate the MTRRs.
  1137. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1138. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1139. write-combining. All of these processors are supported by this code
  1140. and it makes sense to say Y here if you have one of them.
  1141. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1142. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1143. can lead to all sorts of problems, so it's good to say Y here.
  1144. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1145. just add about 9 KB to your kernel.
  1146. See <file:Documentation/x86/mtrr.txt> for more information.
  1147. config MTRR_SANITIZER
  1148. def_bool y
  1149. prompt "MTRR cleanup support"
  1150. depends on MTRR
  1151. ---help---
  1152. Convert MTRR layout from continuous to discrete, so X drivers can
  1153. add writeback entries.
  1154. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1155. The largest mtrr entry size for a continuous block can be set with
  1156. mtrr_chunk_size.
  1157. If unsure, say Y.
  1158. config MTRR_SANITIZER_ENABLE_DEFAULT
  1159. int "MTRR cleanup enable value (0-1)"
  1160. range 0 1
  1161. default "0"
  1162. depends on MTRR_SANITIZER
  1163. ---help---
  1164. Enable mtrr cleanup default value
  1165. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1166. int "MTRR cleanup spare reg num (0-7)"
  1167. range 0 7
  1168. default "1"
  1169. depends on MTRR_SANITIZER
  1170. ---help---
  1171. mtrr cleanup spare entries default, it can be changed via
  1172. mtrr_spare_reg_nr=N on the kernel command line.
  1173. config X86_PAT
  1174. def_bool y
  1175. prompt "x86 PAT support" if EMBEDDED
  1176. depends on MTRR
  1177. ---help---
  1178. Use PAT attributes to setup page level cache control.
  1179. PATs are the modern equivalents of MTRRs and are much more
  1180. flexible than MTRRs.
  1181. Say N here if you see bootup problems (boot crash, boot hang,
  1182. spontaneous reboots) or a non-working video driver.
  1183. If unsure, say Y.
  1184. config ARCH_USES_PG_UNCACHED
  1185. def_bool y
  1186. depends on X86_PAT
  1187. config EFI
  1188. bool "EFI runtime service support"
  1189. depends on ACPI
  1190. ---help---
  1191. This enables the kernel to use EFI runtime services that are
  1192. available (such as the EFI variable services).
  1193. This option is only useful on systems that have EFI firmware.
  1194. In addition, you should use the latest ELILO loader available
  1195. at <http://elilo.sourceforge.net> in order to take advantage
  1196. of EFI runtime services. However, even with this option, the
  1197. resultant kernel should continue to boot on existing non-EFI
  1198. platforms.
  1199. config SECCOMP
  1200. def_bool y
  1201. prompt "Enable seccomp to safely compute untrusted bytecode"
  1202. ---help---
  1203. This kernel feature is useful for number crunching applications
  1204. that may need to compute untrusted bytecode during their
  1205. execution. By using pipes or other transports made available to
  1206. the process as file descriptors supporting the read/write
  1207. syscalls, it's possible to isolate those applications in
  1208. their own address space using seccomp. Once seccomp is
  1209. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1210. and the task is only allowed to execute a few safe syscalls
  1211. defined by each seccomp mode.
  1212. If unsure, say Y. Only embedded should say N here.
  1213. config CC_STACKPROTECTOR
  1214. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1215. ---help---
  1216. This option turns on the -fstack-protector GCC feature. This
  1217. feature puts, at the beginning of functions, a canary value on
  1218. the stack just before the return address, and validates
  1219. the value just before actually returning. Stack based buffer
  1220. overflows (that need to overwrite this return address) now also
  1221. overwrite the canary, which gets detected and the attack is then
  1222. neutralized via a kernel panic.
  1223. This feature requires gcc version 4.2 or above, or a distribution
  1224. gcc with the feature backported. Older versions are automatically
  1225. detected and for those versions, this configuration option is
  1226. ignored. (and a warning is printed during bootup)
  1227. source kernel/Kconfig.hz
  1228. config KEXEC
  1229. bool "kexec system call"
  1230. ---help---
  1231. kexec is a system call that implements the ability to shutdown your
  1232. current kernel, and to start another kernel. It is like a reboot
  1233. but it is independent of the system firmware. And like a reboot
  1234. you can start any kernel with it, not just Linux.
  1235. The name comes from the similarity to the exec system call.
  1236. It is an ongoing process to be certain the hardware in a machine
  1237. is properly shutdown, so do not be surprised if this code does not
  1238. initially work for you. It may help to enable device hotplugging
  1239. support. As of this writing the exact hardware interface is
  1240. strongly in flux, so no good recommendation can be made.
  1241. config CRASH_DUMP
  1242. bool "kernel crash dumps"
  1243. depends on X86_64 || (X86_32 && HIGHMEM)
  1244. ---help---
  1245. Generate crash dump after being started by kexec.
  1246. This should be normally only set in special crash dump kernels
  1247. which are loaded in the main kernel with kexec-tools into
  1248. a specially reserved region and then later executed after
  1249. a crash by kdump/kexec. The crash dump kernel must be compiled
  1250. to a memory address not used by the main kernel or BIOS using
  1251. PHYSICAL_START, or it must be built as a relocatable image
  1252. (CONFIG_RELOCATABLE=y).
  1253. For more details see Documentation/kdump/kdump.txt
  1254. config KEXEC_JUMP
  1255. bool "kexec jump (EXPERIMENTAL)"
  1256. depends on EXPERIMENTAL
  1257. depends on KEXEC && HIBERNATION
  1258. ---help---
  1259. Jump between original kernel and kexeced kernel and invoke
  1260. code in physical address mode via KEXEC
  1261. config PHYSICAL_START
  1262. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1263. default "0x1000000"
  1264. ---help---
  1265. This gives the physical address where the kernel is loaded.
  1266. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1267. bzImage will decompress itself to above physical address and
  1268. run from there. Otherwise, bzImage will run from the address where
  1269. it has been loaded by the boot loader and will ignore above physical
  1270. address.
  1271. In normal kdump cases one does not have to set/change this option
  1272. as now bzImage can be compiled as a completely relocatable image
  1273. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1274. address. This option is mainly useful for the folks who don't want
  1275. to use a bzImage for capturing the crash dump and want to use a
  1276. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1277. to be specifically compiled to run from a specific memory area
  1278. (normally a reserved region) and this option comes handy.
  1279. So if you are using bzImage for capturing the crash dump,
  1280. leave the value here unchanged to 0x1000000 and set
  1281. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1282. for capturing the crash dump change this value to start of
  1283. the reserved region. In other words, it can be set based on
  1284. the "X" value as specified in the "crashkernel=YM@XM"
  1285. command line boot parameter passed to the panic-ed
  1286. kernel. Please take a look at Documentation/kdump/kdump.txt
  1287. for more details about crash dumps.
  1288. Usage of bzImage for capturing the crash dump is recommended as
  1289. one does not have to build two kernels. Same kernel can be used
  1290. as production kernel and capture kernel. Above option should have
  1291. gone away after relocatable bzImage support is introduced. But it
  1292. is present because there are users out there who continue to use
  1293. vmlinux for dump capture. This option should go away down the
  1294. line.
  1295. Don't change this unless you know what you are doing.
  1296. config RELOCATABLE
  1297. bool "Build a relocatable kernel"
  1298. default y
  1299. ---help---
  1300. This builds a kernel image that retains relocation information
  1301. so it can be loaded someplace besides the default 1MB.
  1302. The relocations tend to make the kernel binary about 10% larger,
  1303. but are discarded at runtime.
  1304. One use is for the kexec on panic case where the recovery kernel
  1305. must live at a different physical address than the primary
  1306. kernel.
  1307. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1308. it has been loaded at and the compile time physical address
  1309. (CONFIG_PHYSICAL_START) is ignored.
  1310. # Relocation on x86-32 needs some additional build support
  1311. config X86_NEED_RELOCS
  1312. def_bool y
  1313. depends on X86_32 && RELOCATABLE
  1314. config PHYSICAL_ALIGN
  1315. hex "Alignment value to which kernel should be aligned" if X86_32
  1316. default "0x1000000"
  1317. range 0x2000 0x1000000
  1318. ---help---
  1319. This value puts the alignment restrictions on physical address
  1320. where kernel is loaded and run from. Kernel is compiled for an
  1321. address which meets above alignment restriction.
  1322. If bootloader loads the kernel at a non-aligned address and
  1323. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1324. address aligned to above value and run from there.
  1325. If bootloader loads the kernel at a non-aligned address and
  1326. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1327. load address and decompress itself to the address it has been
  1328. compiled for and run from there. The address for which kernel is
  1329. compiled already meets above alignment restrictions. Hence the
  1330. end result is that kernel runs from a physical address meeting
  1331. above alignment restrictions.
  1332. Don't change this unless you know what you are doing.
  1333. config HOTPLUG_CPU
  1334. bool "Support for hot-pluggable CPUs"
  1335. depends on SMP && HOTPLUG
  1336. ---help---
  1337. Say Y here to allow turning CPUs off and on. CPUs can be
  1338. controlled through /sys/devices/system/cpu.
  1339. ( Note: power management support will enable this option
  1340. automatically on SMP systems. )
  1341. Say N if you want to disable CPU hotplug.
  1342. config COMPAT_VDSO
  1343. def_bool y
  1344. prompt "Compat VDSO support"
  1345. depends on X86_32 || IA32_EMULATION
  1346. ---help---
  1347. Map the 32-bit VDSO to the predictable old-style address too.
  1348. Say N here if you are running a sufficiently recent glibc
  1349. version (2.3.3 or later), to remove the high-mapped
  1350. VDSO mapping and to exclusively use the randomized VDSO.
  1351. If unsure, say Y.
  1352. config CMDLINE_BOOL
  1353. bool "Built-in kernel command line"
  1354. ---help---
  1355. Allow for specifying boot arguments to the kernel at
  1356. build time. On some systems (e.g. embedded ones), it is
  1357. necessary or convenient to provide some or all of the
  1358. kernel boot arguments with the kernel itself (that is,
  1359. to not rely on the boot loader to provide them.)
  1360. To compile command line arguments into the kernel,
  1361. set this option to 'Y', then fill in the
  1362. the boot arguments in CONFIG_CMDLINE.
  1363. Systems with fully functional boot loaders (i.e. non-embedded)
  1364. should leave this option set to 'N'.
  1365. config CMDLINE
  1366. string "Built-in kernel command string"
  1367. depends on CMDLINE_BOOL
  1368. default ""
  1369. ---help---
  1370. Enter arguments here that should be compiled into the kernel
  1371. image and used at boot time. If the boot loader provides a
  1372. command line at boot time, it is appended to this string to
  1373. form the full kernel command line, when the system boots.
  1374. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1375. change this behavior.
  1376. In most cases, the command line (whether built-in or provided
  1377. by the boot loader) should specify the device for the root
  1378. file system.
  1379. config CMDLINE_OVERRIDE
  1380. bool "Built-in command line overrides boot loader arguments"
  1381. depends on CMDLINE_BOOL
  1382. ---help---
  1383. Set this option to 'Y' to have the kernel ignore the boot loader
  1384. command line, and use ONLY the built-in command line.
  1385. This is used to work around broken boot loaders. This should
  1386. be set to 'N' under normal conditions.
  1387. endmenu
  1388. config ARCH_ENABLE_MEMORY_HOTPLUG
  1389. def_bool y
  1390. depends on X86_64 || (X86_32 && HIGHMEM)
  1391. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1392. def_bool y
  1393. depends on MEMORY_HOTPLUG
  1394. config HAVE_ARCH_EARLY_PFN_TO_NID
  1395. def_bool X86_64
  1396. depends on NUMA
  1397. config USE_PERCPU_NUMA_NODE_ID
  1398. def_bool X86_64
  1399. depends on NUMA
  1400. menu "Power management and ACPI options"
  1401. config ARCH_HIBERNATION_HEADER
  1402. def_bool y
  1403. depends on X86_64 && HIBERNATION
  1404. source "kernel/power/Kconfig"
  1405. source "drivers/acpi/Kconfig"
  1406. source "drivers/sfi/Kconfig"
  1407. config X86_APM_BOOT
  1408. def_bool y
  1409. depends on APM || APM_MODULE
  1410. menuconfig APM
  1411. tristate "APM (Advanced Power Management) BIOS support"
  1412. depends on X86_32 && PM_SLEEP
  1413. ---help---
  1414. APM is a BIOS specification for saving power using several different
  1415. techniques. This is mostly useful for battery powered laptops with
  1416. APM compliant BIOSes. If you say Y here, the system time will be
  1417. reset after a RESUME operation, the /proc/apm device will provide
  1418. battery status information, and user-space programs will receive
  1419. notification of APM "events" (e.g. battery status change).
  1420. If you select "Y" here, you can disable actual use of the APM
  1421. BIOS by passing the "apm=off" option to the kernel at boot time.
  1422. Note that the APM support is almost completely disabled for
  1423. machines with more than one CPU.
  1424. In order to use APM, you will need supporting software. For location
  1425. and more information, read <file:Documentation/power/pm.txt> and the
  1426. Battery Powered Linux mini-HOWTO, available from
  1427. <http://www.tldp.org/docs.html#howto>.
  1428. This driver does not spin down disk drives (see the hdparm(8)
  1429. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1430. VESA-compliant "green" monitors.
  1431. This driver does not support the TI 4000M TravelMate and the ACER
  1432. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1433. desktop machines also don't have compliant BIOSes, and this driver
  1434. may cause those machines to panic during the boot phase.
  1435. Generally, if you don't have a battery in your machine, there isn't
  1436. much point in using this driver and you should say N. If you get
  1437. random kernel OOPSes or reboots that don't seem to be related to
  1438. anything, try disabling/enabling this option (or disabling/enabling
  1439. APM in your BIOS).
  1440. Some other things you should try when experiencing seemingly random,
  1441. "weird" problems:
  1442. 1) make sure that you have enough swap space and that it is
  1443. enabled.
  1444. 2) pass the "no-hlt" option to the kernel
  1445. 3) switch on floating point emulation in the kernel and pass
  1446. the "no387" option to the kernel
  1447. 4) pass the "floppy=nodma" option to the kernel
  1448. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1449. all but the first 4 MB of RAM)
  1450. 6) make sure that the CPU is not over clocked.
  1451. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1452. 8) disable the cache from your BIOS settings
  1453. 9) install a fan for the video card or exchange video RAM
  1454. 10) install a better fan for the CPU
  1455. 11) exchange RAM chips
  1456. 12) exchange the motherboard.
  1457. To compile this driver as a module, choose M here: the
  1458. module will be called apm.
  1459. if APM
  1460. config APM_IGNORE_USER_SUSPEND
  1461. bool "Ignore USER SUSPEND"
  1462. ---help---
  1463. This option will ignore USER SUSPEND requests. On machines with a
  1464. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1465. series notebooks, it is necessary to say Y because of a BIOS bug.
  1466. config APM_DO_ENABLE
  1467. bool "Enable PM at boot time"
  1468. ---help---
  1469. Enable APM features at boot time. From page 36 of the APM BIOS
  1470. specification: "When disabled, the APM BIOS does not automatically
  1471. power manage devices, enter the Standby State, enter the Suspend
  1472. State, or take power saving steps in response to CPU Idle calls."
  1473. This driver will make CPU Idle calls when Linux is idle (unless this
  1474. feature is turned off -- see "Do CPU IDLE calls", below). This
  1475. should always save battery power, but more complicated APM features
  1476. will be dependent on your BIOS implementation. You may need to turn
  1477. this option off if your computer hangs at boot time when using APM
  1478. support, or if it beeps continuously instead of suspending. Turn
  1479. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1480. T400CDT. This is off by default since most machines do fine without
  1481. this feature.
  1482. config APM_CPU_IDLE
  1483. bool "Make CPU Idle calls when idle"
  1484. ---help---
  1485. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1486. On some machines, this can activate improved power savings, such as
  1487. a slowed CPU clock rate, when the machine is idle. These idle calls
  1488. are made after the idle loop has run for some length of time (e.g.,
  1489. 333 mS). On some machines, this will cause a hang at boot time or
  1490. whenever the CPU becomes idle. (On machines with more than one CPU,
  1491. this option does nothing.)
  1492. config APM_DISPLAY_BLANK
  1493. bool "Enable console blanking using APM"
  1494. ---help---
  1495. Enable console blanking using the APM. Some laptops can use this to
  1496. turn off the LCD backlight when the screen blanker of the Linux
  1497. virtual console blanks the screen. Note that this is only used by
  1498. the virtual console screen blanker, and won't turn off the backlight
  1499. when using the X Window system. This also doesn't have anything to
  1500. do with your VESA-compliant power-saving monitor. Further, this
  1501. option doesn't work for all laptops -- it might not turn off your
  1502. backlight at all, or it might print a lot of errors to the console,
  1503. especially if you are using gpm.
  1504. config APM_ALLOW_INTS
  1505. bool "Allow interrupts during APM BIOS calls"
  1506. ---help---
  1507. Normally we disable external interrupts while we are making calls to
  1508. the APM BIOS as a measure to lessen the effects of a badly behaving
  1509. BIOS implementation. The BIOS should reenable interrupts if it
  1510. needs to. Unfortunately, some BIOSes do not -- especially those in
  1511. many of the newer IBM Thinkpads. If you experience hangs when you
  1512. suspend, try setting this to Y. Otherwise, say N.
  1513. endif # APM
  1514. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1515. source "drivers/cpuidle/Kconfig"
  1516. source "drivers/idle/Kconfig"
  1517. endmenu
  1518. menu "Bus options (PCI etc.)"
  1519. config PCI
  1520. bool "PCI support"
  1521. default y
  1522. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1523. ---help---
  1524. Find out whether you have a PCI motherboard. PCI is the name of a
  1525. bus system, i.e. the way the CPU talks to the other stuff inside
  1526. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1527. VESA. If you have PCI, say Y, otherwise N.
  1528. choice
  1529. prompt "PCI access mode"
  1530. depends on X86_32 && PCI
  1531. default PCI_GOANY
  1532. ---help---
  1533. On PCI systems, the BIOS can be used to detect the PCI devices and
  1534. determine their configuration. However, some old PCI motherboards
  1535. have BIOS bugs and may crash if this is done. Also, some embedded
  1536. PCI-based systems don't have any BIOS at all. Linux can also try to
  1537. detect the PCI hardware directly without using the BIOS.
  1538. With this option, you can specify how Linux should detect the
  1539. PCI devices. If you choose "BIOS", the BIOS will be used,
  1540. if you choose "Direct", the BIOS won't be used, and if you
  1541. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1542. If you choose "Any", the kernel will try MMCONFIG, then the
  1543. direct access method and falls back to the BIOS if that doesn't
  1544. work. If unsure, go with the default, which is "Any".
  1545. config PCI_GOBIOS
  1546. bool "BIOS"
  1547. config PCI_GOMMCONFIG
  1548. bool "MMConfig"
  1549. config PCI_GODIRECT
  1550. bool "Direct"
  1551. config PCI_GOOLPC
  1552. bool "OLPC"
  1553. depends on OLPC
  1554. config PCI_GOANY
  1555. bool "Any"
  1556. endchoice
  1557. config PCI_BIOS
  1558. def_bool y
  1559. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1560. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1561. config PCI_DIRECT
  1562. def_bool y
  1563. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1564. config PCI_MMCONFIG
  1565. def_bool y
  1566. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1567. config PCI_OLPC
  1568. def_bool y
  1569. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1570. config PCI_DOMAINS
  1571. def_bool y
  1572. depends on PCI
  1573. config PCI_MMCONFIG
  1574. bool "Support mmconfig PCI config space access"
  1575. depends on X86_64 && PCI && ACPI
  1576. config PCI_CNB20LE_QUIRK
  1577. bool "Read CNB20LE Host Bridge Windows"
  1578. depends on PCI
  1579. help
  1580. Read the PCI windows out of the CNB20LE host bridge. This allows
  1581. PCI hotplug to work on systems with the CNB20LE chipset which do
  1582. not have ACPI.
  1583. config DMAR
  1584. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1585. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1586. help
  1587. DMA remapping (DMAR) devices support enables independent address
  1588. translations for Direct Memory Access (DMA) from devices.
  1589. These DMA remapping devices are reported via ACPI tables
  1590. and include PCI device scope covered by these DMA
  1591. remapping devices.
  1592. config DMAR_DEFAULT_ON
  1593. def_bool y
  1594. prompt "Enable DMA Remapping Devices by default"
  1595. depends on DMAR
  1596. help
  1597. Selecting this option will enable a DMAR device at boot time if
  1598. one is found. If this option is not selected, DMAR support can
  1599. be enabled by passing intel_iommu=on to the kernel. It is
  1600. recommended you say N here while the DMAR code remains
  1601. experimental.
  1602. config DMAR_BROKEN_GFX_WA
  1603. bool "Workaround broken graphics drivers (going away soon)"
  1604. depends on DMAR && BROKEN
  1605. ---help---
  1606. Current Graphics drivers tend to use physical address
  1607. for DMA and avoid using DMA APIs. Setting this config
  1608. option permits the IOMMU driver to set a unity map for
  1609. all the OS-visible memory. Hence the driver can continue
  1610. to use physical addresses for DMA, at least until this
  1611. option is removed in the 2.6.32 kernel.
  1612. config DMAR_FLOPPY_WA
  1613. def_bool y
  1614. depends on DMAR
  1615. ---help---
  1616. Floppy disk drivers are known to bypass DMA API calls
  1617. thereby failing to work when IOMMU is enabled. This
  1618. workaround will setup a 1:1 mapping for the first
  1619. 16MiB to make floppy (an ISA device) work.
  1620. config INTR_REMAP
  1621. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1622. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1623. ---help---
  1624. Supports Interrupt remapping for IO-APIC and MSI devices.
  1625. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1626. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1627. source "drivers/pci/pcie/Kconfig"
  1628. source "drivers/pci/Kconfig"
  1629. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1630. config ISA_DMA_API
  1631. def_bool y
  1632. if X86_32
  1633. config ISA
  1634. bool "ISA support"
  1635. ---help---
  1636. Find out whether you have ISA slots on your motherboard. ISA is the
  1637. name of a bus system, i.e. the way the CPU talks to the other stuff
  1638. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1639. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1640. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1641. config EISA
  1642. bool "EISA support"
  1643. depends on ISA
  1644. ---help---
  1645. The Extended Industry Standard Architecture (EISA) bus was
  1646. developed as an open alternative to the IBM MicroChannel bus.
  1647. The EISA bus provided some of the features of the IBM MicroChannel
  1648. bus while maintaining backward compatibility with cards made for
  1649. the older ISA bus. The EISA bus saw limited use between 1988 and
  1650. 1995 when it was made obsolete by the PCI bus.
  1651. Say Y here if you are building a kernel for an EISA-based machine.
  1652. Otherwise, say N.
  1653. source "drivers/eisa/Kconfig"
  1654. config MCA
  1655. bool "MCA support"
  1656. ---help---
  1657. MicroChannel Architecture is found in some IBM PS/2 machines and
  1658. laptops. It is a bus system similar to PCI or ISA. See
  1659. <file:Documentation/mca.txt> (and especially the web page given
  1660. there) before attempting to build an MCA bus kernel.
  1661. source "drivers/mca/Kconfig"
  1662. config SCx200
  1663. tristate "NatSemi SCx200 support"
  1664. ---help---
  1665. This provides basic support for National Semiconductor's
  1666. (now AMD's) Geode processors. The driver probes for the
  1667. PCI-IDs of several on-chip devices, so its a good dependency
  1668. for other scx200_* drivers.
  1669. If compiled as a module, the driver is named scx200.
  1670. config SCx200HR_TIMER
  1671. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1672. depends on SCx200
  1673. default y
  1674. ---help---
  1675. This driver provides a clocksource built upon the on-chip
  1676. 27MHz high-resolution timer. Its also a workaround for
  1677. NSC Geode SC-1100's buggy TSC, which loses time when the
  1678. processor goes idle (as is done by the scheduler). The
  1679. other workaround is idle=poll boot option.
  1680. config OLPC
  1681. bool "One Laptop Per Child support"
  1682. select GPIOLIB
  1683. ---help---
  1684. Add support for detecting the unique features of the OLPC
  1685. XO hardware.
  1686. config OLPC_OPENFIRMWARE
  1687. bool "Support for OLPC's Open Firmware"
  1688. depends on !X86_64 && !X86_PAE
  1689. default y if OLPC
  1690. help
  1691. This option adds support for the implementation of Open Firmware
  1692. that is used on the OLPC XO-1 Children's Machine.
  1693. If unsure, say N here.
  1694. endif # X86_32
  1695. config K8_NB
  1696. def_bool y
  1697. depends on CPU_SUP_AMD && PCI
  1698. source "drivers/pcmcia/Kconfig"
  1699. source "drivers/pci/hotplug/Kconfig"
  1700. endmenu
  1701. menu "Executable file formats / Emulations"
  1702. source "fs/Kconfig.binfmt"
  1703. config IA32_EMULATION
  1704. bool "IA32 Emulation"
  1705. depends on X86_64
  1706. select COMPAT_BINFMT_ELF
  1707. ---help---
  1708. Include code to run 32-bit programs under a 64-bit kernel. You should
  1709. likely turn this on, unless you're 100% sure that you don't have any
  1710. 32-bit programs left.
  1711. config IA32_AOUT
  1712. tristate "IA32 a.out support"
  1713. depends on IA32_EMULATION
  1714. ---help---
  1715. Support old a.out binaries in the 32bit emulation.
  1716. config COMPAT
  1717. def_bool y
  1718. depends on IA32_EMULATION
  1719. config COMPAT_FOR_U64_ALIGNMENT
  1720. def_bool COMPAT
  1721. depends on X86_64
  1722. config SYSVIPC_COMPAT
  1723. def_bool y
  1724. depends on COMPAT && SYSVIPC
  1725. endmenu
  1726. config HAVE_ATOMIC_IOMAP
  1727. def_bool y
  1728. depends on X86_32
  1729. source "net/Kconfig"
  1730. source "drivers/Kconfig"
  1731. source "drivers/firmware/Kconfig"
  1732. source "fs/Kconfig"
  1733. source "arch/x86/Kconfig.debug"
  1734. source "security/Kconfig"
  1735. source "crypto/Kconfig"
  1736. source "arch/x86/kvm/Kconfig"
  1737. source "lib/Kconfig"