Kconfig 66 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_IOREMAP_PROT
  24. select HAVE_KPROBES
  25. select ARCH_WANT_OPTIONAL_GPIOLIB
  26. select ARCH_WANT_FRAME_POINTERS
  27. select HAVE_KRETPROBES
  28. select HAVE_FTRACE_MCOUNT_RECORD
  29. select HAVE_DYNAMIC_FTRACE
  30. select HAVE_FUNCTION_TRACER
  31. select HAVE_FUNCTION_GRAPH_TRACER
  32. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  33. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  34. select HAVE_FTRACE_SYSCALLS
  35. select HAVE_KVM
  36. select HAVE_ARCH_KGDB
  37. select HAVE_ARCH_TRACEHOOK
  38. select HAVE_GENERIC_DMA_COHERENT if X86_32
  39. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  40. select USER_STACKTRACE_SUPPORT
  41. select HAVE_DMA_API_DEBUG
  42. select HAVE_KERNEL_GZIP
  43. select HAVE_KERNEL_BZIP2
  44. select HAVE_KERNEL_LZMA
  45. config OUTPUT_FORMAT
  46. string
  47. default "elf32-i386" if X86_32
  48. default "elf64-x86-64" if X86_64
  49. config ARCH_DEFCONFIG
  50. string
  51. default "arch/x86/configs/i386_defconfig" if X86_32
  52. default "arch/x86/configs/x86_64_defconfig" if X86_64
  53. config GENERIC_TIME
  54. def_bool y
  55. config GENERIC_CMOS_UPDATE
  56. def_bool y
  57. config CLOCKSOURCE_WATCHDOG
  58. def_bool y
  59. config GENERIC_CLOCKEVENTS
  60. def_bool y
  61. config GENERIC_CLOCKEVENTS_BROADCAST
  62. def_bool y
  63. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  64. config LOCKDEP_SUPPORT
  65. def_bool y
  66. config STACKTRACE_SUPPORT
  67. def_bool y
  68. config HAVE_LATENCYTOP_SUPPORT
  69. def_bool y
  70. config FAST_CMPXCHG_LOCAL
  71. bool
  72. default y
  73. config MMU
  74. def_bool y
  75. config ZONE_DMA
  76. def_bool y
  77. config SBUS
  78. bool
  79. config GENERIC_ISA_DMA
  80. def_bool y
  81. config GENERIC_IOMAP
  82. def_bool y
  83. config GENERIC_BUG
  84. def_bool y
  85. depends on BUG
  86. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  87. config GENERIC_BUG_RELATIVE_POINTERS
  88. bool
  89. config GENERIC_HWEIGHT
  90. def_bool y
  91. config GENERIC_GPIO
  92. bool
  93. config ARCH_MAY_HAVE_PC_FDC
  94. def_bool y
  95. config RWSEM_GENERIC_SPINLOCK
  96. def_bool !X86_XADD
  97. config RWSEM_XCHGADD_ALGORITHM
  98. def_bool X86_XADD
  99. config ARCH_HAS_CPU_IDLE_WAIT
  100. def_bool y
  101. config GENERIC_CALIBRATE_DELAY
  102. def_bool y
  103. config GENERIC_TIME_VSYSCALL
  104. bool
  105. default X86_64
  106. config ARCH_HAS_CPU_RELAX
  107. def_bool y
  108. config ARCH_HAS_DEFAULT_IDLE
  109. def_bool y
  110. config ARCH_HAS_CACHE_LINE_SIZE
  111. def_bool y
  112. config HAVE_SETUP_PER_CPU_AREA
  113. def_bool y
  114. config HAVE_DYNAMIC_PER_CPU_AREA
  115. def_bool y
  116. config HAVE_CPUMASK_OF_CPU_MAP
  117. def_bool X86_64_SMP
  118. config ARCH_HIBERNATION_POSSIBLE
  119. def_bool y
  120. config ARCH_SUSPEND_POSSIBLE
  121. def_bool y
  122. config ZONE_DMA32
  123. bool
  124. default X86_64
  125. config ARCH_POPULATES_NODE_MAP
  126. def_bool y
  127. config AUDIT_ARCH
  128. bool
  129. default X86_64
  130. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  131. def_bool y
  132. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  133. def_bool y
  134. # Use the generic interrupt handling code in kernel/irq/:
  135. config GENERIC_HARDIRQS
  136. bool
  137. default y
  138. config GENERIC_HARDIRQS_NO__DO_IRQ
  139. def_bool y
  140. config GENERIC_IRQ_PROBE
  141. bool
  142. default y
  143. config GENERIC_PENDING_IRQ
  144. bool
  145. depends on GENERIC_HARDIRQS && SMP
  146. default y
  147. config USE_GENERIC_SMP_HELPERS
  148. def_bool y
  149. depends on SMP
  150. config X86_32_SMP
  151. def_bool y
  152. depends on X86_32 && SMP
  153. config X86_64_SMP
  154. def_bool y
  155. depends on X86_64 && SMP
  156. config X86_HT
  157. bool
  158. depends on SMP
  159. default y
  160. config X86_TRAMPOLINE
  161. bool
  162. depends on SMP || (64BIT && ACPI_SLEEP)
  163. default y
  164. config X86_32_LAZY_GS
  165. def_bool y
  166. depends on X86_32 && !CC_STACKPROTECTOR
  167. config KTIME_SCALAR
  168. def_bool X86_32
  169. source "init/Kconfig"
  170. source "kernel/Kconfig.freezer"
  171. menu "Processor type and features"
  172. source "kernel/time/Kconfig"
  173. config SMP
  174. bool "Symmetric multi-processing support"
  175. ---help---
  176. This enables support for systems with more than one CPU. If you have
  177. a system with only one CPU, like most personal computers, say N. If
  178. you have a system with more than one CPU, say Y.
  179. If you say N here, the kernel will run on single and multiprocessor
  180. machines, but will use only one CPU of a multiprocessor machine. If
  181. you say Y here, the kernel will run on many, but not all,
  182. singleprocessor machines. On a singleprocessor machine, the kernel
  183. will run faster if you say N here.
  184. Note that if you say Y here and choose architecture "586" or
  185. "Pentium" under "Processor family", the kernel will not work on 486
  186. architectures. Similarly, multiprocessor kernels for the "PPro"
  187. architecture may not work on all Pentium based boards.
  188. People using multiprocessor machines who say Y here should also say
  189. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  190. Management" code will be disabled if you say Y here.
  191. See also <file:Documentation/i386/IO-APIC.txt>,
  192. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  193. <http://www.tldp.org/docs.html#howto>.
  194. If you don't know what to do here, say N.
  195. config X86_X2APIC
  196. bool "Support x2apic"
  197. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  198. ---help---
  199. This enables x2apic support on CPUs that have this feature.
  200. This allows 32-bit apic IDs (so it can support very large systems),
  201. and accesses the local apic via MSRs not via mmio.
  202. If you don't know what to do here, say N.
  203. config SPARSE_IRQ
  204. bool "Support sparse irq numbering"
  205. depends on PCI_MSI || HT_IRQ
  206. ---help---
  207. This enables support for sparse irqs. This is useful for distro
  208. kernels that want to define a high CONFIG_NR_CPUS value but still
  209. want to have low kernel memory footprint on smaller machines.
  210. ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
  211. out the irq_desc[] array in a more NUMA-friendly way. )
  212. If you don't know what to do here, say N.
  213. config NUMA_IRQ_DESC
  214. def_bool y
  215. depends on SPARSE_IRQ && NUMA
  216. config X86_MPPARSE
  217. bool "Enable MPS table" if ACPI
  218. default y
  219. depends on X86_LOCAL_APIC
  220. ---help---
  221. For old smp systems that do not have proper acpi support. Newer systems
  222. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  223. config X86_BIGSMP
  224. bool "Support for big SMP systems with more than 8 CPUs"
  225. depends on X86_32 && SMP
  226. ---help---
  227. This option is needed for the systems that have more than 8 CPUs
  228. if X86_32
  229. config X86_EXTENDED_PLATFORM
  230. bool "Support for extended (non-PC) x86 platforms"
  231. default y
  232. ---help---
  233. If you disable this option then the kernel will only support
  234. standard PC platforms. (which covers the vast majority of
  235. systems out there.)
  236. If you enable this option then you'll be able to select support
  237. for the following (non-PC) 32 bit x86 platforms:
  238. AMD Elan
  239. NUMAQ (IBM/Sequent)
  240. RDC R-321x SoC
  241. SGI 320/540 (Visual Workstation)
  242. Summit/EXA (IBM x440)
  243. Unisys ES7000 IA32 series
  244. If you have one of these systems, or if you want to build a
  245. generic distribution kernel, say Y here - otherwise say N.
  246. endif
  247. if X86_64
  248. config X86_EXTENDED_PLATFORM
  249. bool "Support for extended (non-PC) x86 platforms"
  250. default y
  251. ---help---
  252. If you disable this option then the kernel will only support
  253. standard PC platforms. (which covers the vast majority of
  254. systems out there.)
  255. If you enable this option then you'll be able to select support
  256. for the following (non-PC) 64 bit x86 platforms:
  257. ScaleMP vSMP
  258. SGI Ultraviolet
  259. If you have one of these systems, or if you want to build a
  260. generic distribution kernel, say Y here - otherwise say N.
  261. endif
  262. # This is an alphabetically sorted list of 64 bit extended platforms
  263. # Please maintain the alphabetic order if and when there are additions
  264. config X86_VSMP
  265. bool "ScaleMP vSMP"
  266. select PARAVIRT
  267. depends on X86_64 && PCI
  268. depends on X86_EXTENDED_PLATFORM
  269. ---help---
  270. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  271. supposed to run on these EM64T-based machines. Only choose this option
  272. if you have one of these machines.
  273. config X86_UV
  274. bool "SGI Ultraviolet"
  275. depends on X86_64
  276. depends on X86_EXTENDED_PLATFORM
  277. depends on NUMA
  278. depends on X86_X2APIC
  279. ---help---
  280. This option is needed in order to support SGI Ultraviolet systems.
  281. If you don't have one of these, you should say N here.
  282. # Following is an alphabetically sorted list of 32 bit extended platforms
  283. # Please maintain the alphabetic order if and when there are additions
  284. config X86_ELAN
  285. bool "AMD Elan"
  286. depends on X86_32
  287. depends on X86_EXTENDED_PLATFORM
  288. ---help---
  289. Select this for an AMD Elan processor.
  290. Do not use this option for K6/Athlon/Opteron processors!
  291. If unsure, choose "PC-compatible" instead.
  292. config X86_RDC321X
  293. bool "RDC R-321x SoC"
  294. depends on X86_32
  295. depends on X86_EXTENDED_PLATFORM
  296. select M486
  297. select X86_REBOOTFIXUPS
  298. ---help---
  299. This option is needed for RDC R-321x system-on-chip, also known
  300. as R-8610-(G).
  301. If you don't have one of these chips, you should say N here.
  302. config X86_32_NON_STANDARD
  303. bool "Support non-standard 32-bit SMP architectures"
  304. depends on X86_32 && SMP
  305. depends on X86_EXTENDED_PLATFORM
  306. ---help---
  307. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  308. subarchitectures. It is intended for a generic binary kernel.
  309. if you select them all, kernel will probe it one by one. and will
  310. fallback to default.
  311. # Alphabetically sorted list of Non standard 32 bit platforms
  312. config X86_NUMAQ
  313. bool "NUMAQ (IBM/Sequent)"
  314. depends on X86_32_NON_STANDARD
  315. select NUMA
  316. select X86_MPPARSE
  317. ---help---
  318. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  319. NUMA multiquad box. This changes the way that processors are
  320. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  321. of Flat Logical. You will need a new lynxer.elf file to flash your
  322. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  323. config X86_VISWS
  324. bool "SGI 320/540 (Visual Workstation)"
  325. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  326. depends on X86_32_NON_STANDARD
  327. ---help---
  328. The SGI Visual Workstation series is an IA32-based workstation
  329. based on SGI systems chips with some legacy PC hardware attached.
  330. Say Y here to create a kernel to run on the SGI 320 or 540.
  331. A kernel compiled for the Visual Workstation will run on general
  332. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  333. config X86_SUMMIT
  334. bool "Summit/EXA (IBM x440)"
  335. depends on X86_32_NON_STANDARD
  336. ---help---
  337. This option is needed for IBM systems that use the Summit/EXA chipset.
  338. In particular, it is needed for the x440.
  339. config X86_ES7000
  340. bool "Unisys ES7000 IA32 series"
  341. depends on X86_32_NON_STANDARD && X86_BIGSMP
  342. ---help---
  343. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  344. supposed to run on an IA32-based Unisys ES7000 system.
  345. config SCHED_OMIT_FRAME_POINTER
  346. def_bool y
  347. prompt "Single-depth WCHAN output"
  348. depends on X86
  349. ---help---
  350. Calculate simpler /proc/<PID>/wchan values. If this option
  351. is disabled then wchan values will recurse back to the
  352. caller function. This provides more accurate wchan values,
  353. at the expense of slightly more scheduling overhead.
  354. If in doubt, say "Y".
  355. menuconfig PARAVIRT_GUEST
  356. bool "Paravirtualized guest support"
  357. ---help---
  358. Say Y here to get to see options related to running Linux under
  359. various hypervisors. This option alone does not add any kernel code.
  360. If you say N, all options in this submenu will be skipped and disabled.
  361. if PARAVIRT_GUEST
  362. source "arch/x86/xen/Kconfig"
  363. config VMI
  364. bool "VMI Guest support"
  365. select PARAVIRT
  366. depends on X86_32
  367. ---help---
  368. VMI provides a paravirtualized interface to the VMware ESX server
  369. (it could be used by other hypervisors in theory too, but is not
  370. at the moment), by linking the kernel to a GPL-ed ROM module
  371. provided by the hypervisor.
  372. config KVM_CLOCK
  373. bool "KVM paravirtualized clock"
  374. select PARAVIRT
  375. select PARAVIRT_CLOCK
  376. ---help---
  377. Turning on this option will allow you to run a paravirtualized clock
  378. when running over the KVM hypervisor. Instead of relying on a PIT
  379. (or probably other) emulation by the underlying device model, the host
  380. provides the guest with timing infrastructure such as time of day, and
  381. system time
  382. config KVM_GUEST
  383. bool "KVM Guest support"
  384. select PARAVIRT
  385. ---help---
  386. This option enables various optimizations for running under the KVM
  387. hypervisor.
  388. source "arch/x86/lguest/Kconfig"
  389. config PARAVIRT
  390. bool "Enable paravirtualization code"
  391. ---help---
  392. This changes the kernel so it can modify itself when it is run
  393. under a hypervisor, potentially improving performance significantly
  394. over full virtualization. However, when run without a hypervisor
  395. the kernel is theoretically slower and slightly larger.
  396. config PARAVIRT_SPINLOCKS
  397. bool "Paravirtualization layer for spinlocks"
  398. depends on PARAVIRT && SMP && EXPERIMENTAL
  399. ---help---
  400. Paravirtualized spinlocks allow a pvops backend to replace the
  401. spinlock implementation with something virtualization-friendly
  402. (for example, block the virtual CPU rather than spinning).
  403. Unfortunately the downside is an up to 5% performance hit on
  404. native kernels, with various workloads.
  405. If you are unsure how to answer this question, answer N.
  406. config PARAVIRT_CLOCK
  407. bool
  408. default n
  409. endif
  410. config PARAVIRT_DEBUG
  411. bool "paravirt-ops debugging"
  412. depends on PARAVIRT && DEBUG_KERNEL
  413. ---help---
  414. Enable to debug paravirt_ops internals. Specifically, BUG if
  415. a paravirt_op is missing when it is called.
  416. config MEMTEST
  417. bool "Memtest"
  418. ---help---
  419. This option adds a kernel parameter 'memtest', which allows memtest
  420. to be set.
  421. memtest=0, mean disabled; -- default
  422. memtest=1, mean do 1 test pattern;
  423. ...
  424. memtest=4, mean do 4 test patterns.
  425. If you are unsure how to answer this question, answer N.
  426. config X86_SUMMIT_NUMA
  427. def_bool y
  428. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  429. config X86_CYCLONE_TIMER
  430. def_bool y
  431. depends on X86_32_NON_STANDARD
  432. source "arch/x86/Kconfig.cpu"
  433. config HPET_TIMER
  434. def_bool X86_64
  435. prompt "HPET Timer Support" if X86_32
  436. ---help---
  437. Use the IA-PC HPET (High Precision Event Timer) to manage
  438. time in preference to the PIT and RTC, if a HPET is
  439. present.
  440. HPET is the next generation timer replacing legacy 8254s.
  441. The HPET provides a stable time base on SMP
  442. systems, unlike the TSC, but it is more expensive to access,
  443. as it is off-chip. You can find the HPET spec at
  444. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  445. You can safely choose Y here. However, HPET will only be
  446. activated if the platform and the BIOS support this feature.
  447. Otherwise the 8254 will be used for timing services.
  448. Choose N to continue using the legacy 8254 timer.
  449. config HPET_EMULATE_RTC
  450. def_bool y
  451. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  452. # Mark as embedded because too many people got it wrong.
  453. # The code disables itself when not needed.
  454. config DMI
  455. default y
  456. bool "Enable DMI scanning" if EMBEDDED
  457. ---help---
  458. Enabled scanning of DMI to identify machine quirks. Say Y
  459. here unless you have verified that your setup is not
  460. affected by entries in the DMI blacklist. Required by PNP
  461. BIOS code.
  462. config GART_IOMMU
  463. bool "GART IOMMU support" if EMBEDDED
  464. default y
  465. select SWIOTLB
  466. select AGP
  467. depends on X86_64 && PCI
  468. ---help---
  469. Support for full DMA access of devices with 32bit memory access only
  470. on systems with more than 3GB. This is usually needed for USB,
  471. sound, many IDE/SATA chipsets and some other devices.
  472. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  473. based hardware IOMMU and a software bounce buffer based IOMMU used
  474. on Intel systems and as fallback.
  475. The code is only active when needed (enough memory and limited
  476. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  477. too.
  478. config CALGARY_IOMMU
  479. bool "IBM Calgary IOMMU support"
  480. select SWIOTLB
  481. depends on X86_64 && PCI && EXPERIMENTAL
  482. ---help---
  483. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  484. systems. Needed to run systems with more than 3GB of memory
  485. properly with 32-bit PCI devices that do not support DAC
  486. (Double Address Cycle). Calgary also supports bus level
  487. isolation, where all DMAs pass through the IOMMU. This
  488. prevents them from going anywhere except their intended
  489. destination. This catches hard-to-find kernel bugs and
  490. mis-behaving drivers and devices that do not use the DMA-API
  491. properly to set up their DMA buffers. The IOMMU can be
  492. turned off at boot time with the iommu=off parameter.
  493. Normally the kernel will make the right choice by itself.
  494. If unsure, say Y.
  495. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  496. def_bool y
  497. prompt "Should Calgary be enabled by default?"
  498. depends on CALGARY_IOMMU
  499. ---help---
  500. Should Calgary be enabled by default? if you choose 'y', Calgary
  501. will be used (if it exists). If you choose 'n', Calgary will not be
  502. used even if it exists. If you choose 'n' and would like to use
  503. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  504. If unsure, say Y.
  505. config AMD_IOMMU
  506. bool "AMD IOMMU support"
  507. select SWIOTLB
  508. select PCI_MSI
  509. depends on X86_64 && PCI && ACPI
  510. ---help---
  511. With this option you can enable support for AMD IOMMU hardware in
  512. your system. An IOMMU is a hardware component which provides
  513. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  514. can isolate the the DMA memory of different devices and protect the
  515. system from misbehaving device drivers or hardware.
  516. You can find out if your system has an AMD IOMMU if you look into
  517. your BIOS for an option to enable it or if you have an IVRS ACPI
  518. table.
  519. config AMD_IOMMU_STATS
  520. bool "Export AMD IOMMU statistics to debugfs"
  521. depends on AMD_IOMMU
  522. select DEBUG_FS
  523. ---help---
  524. This option enables code in the AMD IOMMU driver to collect various
  525. statistics about whats happening in the driver and exports that
  526. information to userspace via debugfs.
  527. If unsure, say N.
  528. # need this always selected by IOMMU for the VIA workaround
  529. config SWIOTLB
  530. def_bool y if X86_64
  531. ---help---
  532. Support for software bounce buffers used on x86-64 systems
  533. which don't have a hardware IOMMU (e.g. the current generation
  534. of Intel's x86-64 CPUs). Using this PCI devices which can only
  535. access 32-bits of memory can be used on systems with more than
  536. 3 GB of memory. If unsure, say Y.
  537. config IOMMU_HELPER
  538. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  539. config IOMMU_API
  540. def_bool (AMD_IOMMU || DMAR)
  541. config MAXSMP
  542. bool "Configure Maximum number of SMP Processors and NUMA Nodes"
  543. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  544. select CPUMASK_OFFSTACK
  545. default n
  546. ---help---
  547. Configure maximum number of CPUS and NUMA Nodes for this architecture.
  548. If unsure, say N.
  549. config NR_CPUS
  550. int "Maximum number of CPUs" if SMP && !MAXSMP
  551. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  552. range 2 512 if SMP && !MAXSMP
  553. default "1" if !SMP
  554. default "4096" if MAXSMP
  555. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  556. default "8" if SMP
  557. ---help---
  558. This allows you to specify the maximum number of CPUs which this
  559. kernel will support. The maximum supported value is 512 and the
  560. minimum value which makes sense is 2.
  561. This is purely to save memory - each supported CPU adds
  562. approximately eight kilobytes to the kernel image.
  563. config SCHED_SMT
  564. bool "SMT (Hyperthreading) scheduler support"
  565. depends on X86_HT
  566. ---help---
  567. SMT scheduler support improves the CPU scheduler's decision making
  568. when dealing with Intel Pentium 4 chips with HyperThreading at a
  569. cost of slightly increased overhead in some places. If unsure say
  570. N here.
  571. config SCHED_MC
  572. def_bool y
  573. prompt "Multi-core scheduler support"
  574. depends on X86_HT
  575. ---help---
  576. Multi-core scheduler support improves the CPU scheduler's decision
  577. making when dealing with multi-core CPU chips at a cost of slightly
  578. increased overhead in some places. If unsure say N here.
  579. source "kernel/Kconfig.preempt"
  580. config X86_UP_APIC
  581. bool "Local APIC support on uniprocessors"
  582. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  583. ---help---
  584. A local APIC (Advanced Programmable Interrupt Controller) is an
  585. integrated interrupt controller in the CPU. If you have a single-CPU
  586. system which has a processor with a local APIC, you can say Y here to
  587. enable and use it. If you say Y here even though your machine doesn't
  588. have a local APIC, then the kernel will still run with no slowdown at
  589. all. The local APIC supports CPU-generated self-interrupts (timer,
  590. performance counters), and the NMI watchdog which detects hard
  591. lockups.
  592. config X86_UP_IOAPIC
  593. bool "IO-APIC support on uniprocessors"
  594. depends on X86_UP_APIC
  595. ---help---
  596. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  597. SMP-capable replacement for PC-style interrupt controllers. Most
  598. SMP systems and many recent uniprocessor systems have one.
  599. If you have a single-CPU system with an IO-APIC, you can say Y here
  600. to use it. If you say Y here even though your machine doesn't have
  601. an IO-APIC, then the kernel will still run with no slowdown at all.
  602. config X86_LOCAL_APIC
  603. def_bool y
  604. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  605. config X86_IO_APIC
  606. def_bool y
  607. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  608. config X86_VISWS_APIC
  609. def_bool y
  610. depends on X86_32 && X86_VISWS
  611. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  612. bool "Reroute for broken boot IRQs"
  613. default n
  614. depends on X86_IO_APIC
  615. ---help---
  616. This option enables a workaround that fixes a source of
  617. spurious interrupts. This is recommended when threaded
  618. interrupt handling is used on systems where the generation of
  619. superfluous "boot interrupts" cannot be disabled.
  620. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  621. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  622. kernel does during interrupt handling). On chipsets where this
  623. boot IRQ generation cannot be disabled, this workaround keeps
  624. the original IRQ line masked so that only the equivalent "boot
  625. IRQ" is delivered to the CPUs. The workaround also tells the
  626. kernel to set up the IRQ handler on the boot IRQ line. In this
  627. way only one interrupt is delivered to the kernel. Otherwise
  628. the spurious second interrupt may cause the kernel to bring
  629. down (vital) interrupt lines.
  630. Only affects "broken" chipsets. Interrupt sharing may be
  631. increased on these systems.
  632. config X86_MCE
  633. bool "Machine Check Exception"
  634. ---help---
  635. Machine Check Exception support allows the processor to notify the
  636. kernel if it detects a problem (e.g. overheating, component failure).
  637. The action the kernel takes depends on the severity of the problem,
  638. ranging from a warning message on the console, to halting the machine.
  639. Your processor must be a Pentium or newer to support this - check the
  640. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  641. have a design flaw which leads to false MCE events - hence MCE is
  642. disabled on all P5 processors, unless explicitly enabled with "mce"
  643. as a boot argument. Similarly, if MCE is built in and creates a
  644. problem on some new non-standard machine, you can boot with "nomce"
  645. to disable it. MCE support simply ignores non-MCE processors like
  646. the 386 and 486, so nearly everyone can say Y here.
  647. config X86_MCE_INTEL
  648. def_bool y
  649. prompt "Intel MCE features"
  650. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  651. ---help---
  652. Additional support for intel specific MCE features such as
  653. the thermal monitor.
  654. config X86_MCE_AMD
  655. def_bool y
  656. prompt "AMD MCE features"
  657. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  658. ---help---
  659. Additional support for AMD specific MCE features such as
  660. the DRAM Error Threshold.
  661. config X86_MCE_THRESHOLD
  662. depends on X86_MCE_AMD || X86_MCE_INTEL
  663. bool
  664. default y
  665. config X86_MCE_NONFATAL
  666. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  667. depends on X86_32 && X86_MCE
  668. ---help---
  669. Enabling this feature starts a timer that triggers every 5 seconds which
  670. will look at the machine check registers to see if anything happened.
  671. Non-fatal problems automatically get corrected (but still logged).
  672. Disable this if you don't want to see these messages.
  673. Seeing the messages this option prints out may be indicative of dying
  674. or out-of-spec (ie, overclocked) hardware.
  675. This option only does something on certain CPUs.
  676. (AMD Athlon/Duron and Intel Pentium 4)
  677. config X86_MCE_P4THERMAL
  678. bool "check for P4 thermal throttling interrupt."
  679. depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
  680. ---help---
  681. Enabling this feature will cause a message to be printed when the P4
  682. enters thermal throttling.
  683. config VM86
  684. bool "Enable VM86 support" if EMBEDDED
  685. default y
  686. depends on X86_32
  687. ---help---
  688. This option is required by programs like DOSEMU to run 16-bit legacy
  689. code on X86 processors. It also may be needed by software like
  690. XFree86 to initialize some video cards via BIOS. Disabling this
  691. option saves about 6k.
  692. config TOSHIBA
  693. tristate "Toshiba Laptop support"
  694. depends on X86_32
  695. ---help---
  696. This adds a driver to safely access the System Management Mode of
  697. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  698. not work on models with a Phoenix BIOS. The System Management Mode
  699. is used to set the BIOS and power saving options on Toshiba portables.
  700. For information on utilities to make use of this driver see the
  701. Toshiba Linux utilities web site at:
  702. <http://www.buzzard.org.uk/toshiba/>.
  703. Say Y if you intend to run this kernel on a Toshiba portable.
  704. Say N otherwise.
  705. config I8K
  706. tristate "Dell laptop support"
  707. ---help---
  708. This adds a driver to safely access the System Management Mode
  709. of the CPU on the Dell Inspiron 8000. The System Management Mode
  710. is used to read cpu temperature and cooling fan status and to
  711. control the fans on the I8K portables.
  712. This driver has been tested only on the Inspiron 8000 but it may
  713. also work with other Dell laptops. You can force loading on other
  714. models by passing the parameter `force=1' to the module. Use at
  715. your own risk.
  716. For information on utilities to make use of this driver see the
  717. I8K Linux utilities web site at:
  718. <http://people.debian.org/~dz/i8k/>
  719. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  720. Say N otherwise.
  721. config X86_REBOOTFIXUPS
  722. bool "Enable X86 board specific fixups for reboot"
  723. depends on X86_32
  724. ---help---
  725. This enables chipset and/or board specific fixups to be done
  726. in order to get reboot to work correctly. This is only needed on
  727. some combinations of hardware and BIOS. The symptom, for which
  728. this config is intended, is when reboot ends with a stalled/hung
  729. system.
  730. Currently, the only fixup is for the Geode machines using
  731. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  732. Say Y if you want to enable the fixup. Currently, it's safe to
  733. enable this option even if you don't need it.
  734. Say N otherwise.
  735. config MICROCODE
  736. tristate "/dev/cpu/microcode - microcode support"
  737. select FW_LOADER
  738. ---help---
  739. If you say Y here, you will be able to update the microcode on
  740. certain Intel and AMD processors. The Intel support is for the
  741. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  742. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  743. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  744. You will obviously need the actual microcode binary data itself
  745. which is not shipped with the Linux kernel.
  746. This option selects the general module only, you need to select
  747. at least one vendor specific module as well.
  748. To compile this driver as a module, choose M here: the
  749. module will be called microcode.
  750. config MICROCODE_INTEL
  751. bool "Intel microcode patch loading support"
  752. depends on MICROCODE
  753. default MICROCODE
  754. select FW_LOADER
  755. ---help---
  756. This options enables microcode patch loading support for Intel
  757. processors.
  758. For latest news and information on obtaining all the required
  759. Intel ingredients for this driver, check:
  760. <http://www.urbanmyth.org/microcode/>.
  761. config MICROCODE_AMD
  762. bool "AMD microcode patch loading support"
  763. depends on MICROCODE
  764. select FW_LOADER
  765. ---help---
  766. If you select this option, microcode patch loading support for AMD
  767. processors will be enabled.
  768. config MICROCODE_OLD_INTERFACE
  769. def_bool y
  770. depends on MICROCODE
  771. config X86_MSR
  772. tristate "/dev/cpu/*/msr - Model-specific register support"
  773. ---help---
  774. This device gives privileged processes access to the x86
  775. Model-Specific Registers (MSRs). It is a character device with
  776. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  777. MSR accesses are directed to a specific CPU on multi-processor
  778. systems.
  779. config X86_CPUID
  780. tristate "/dev/cpu/*/cpuid - CPU information support"
  781. ---help---
  782. This device gives processes access to the x86 CPUID instruction to
  783. be executed on a specific processor. It is a character device
  784. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  785. /dev/cpu/31/cpuid.
  786. config X86_CPU_DEBUG
  787. tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"
  788. ---help---
  789. If you select this option, this will provide various x86 CPUs
  790. information through debugfs.
  791. choice
  792. prompt "High Memory Support"
  793. default HIGHMEM4G if !X86_NUMAQ
  794. default HIGHMEM64G if X86_NUMAQ
  795. depends on X86_32
  796. config NOHIGHMEM
  797. bool "off"
  798. depends on !X86_NUMAQ
  799. ---help---
  800. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  801. However, the address space of 32-bit x86 processors is only 4
  802. Gigabytes large. That means that, if you have a large amount of
  803. physical memory, not all of it can be "permanently mapped" by the
  804. kernel. The physical memory that's not permanently mapped is called
  805. "high memory".
  806. If you are compiling a kernel which will never run on a machine with
  807. more than 1 Gigabyte total physical RAM, answer "off" here (default
  808. choice and suitable for most users). This will result in a "3GB/1GB"
  809. split: 3GB are mapped so that each process sees a 3GB virtual memory
  810. space and the remaining part of the 4GB virtual memory space is used
  811. by the kernel to permanently map as much physical memory as
  812. possible.
  813. If the machine has between 1 and 4 Gigabytes physical RAM, then
  814. answer "4GB" here.
  815. If more than 4 Gigabytes is used then answer "64GB" here. This
  816. selection turns Intel PAE (Physical Address Extension) mode on.
  817. PAE implements 3-level paging on IA32 processors. PAE is fully
  818. supported by Linux, PAE mode is implemented on all recent Intel
  819. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  820. then the kernel will not boot on CPUs that don't support PAE!
  821. The actual amount of total physical memory will either be
  822. auto detected or can be forced by using a kernel command line option
  823. such as "mem=256M". (Try "man bootparam" or see the documentation of
  824. your boot loader (lilo or loadlin) about how to pass options to the
  825. kernel at boot time.)
  826. If unsure, say "off".
  827. config HIGHMEM4G
  828. bool "4GB"
  829. depends on !X86_NUMAQ
  830. ---help---
  831. Select this if you have a 32-bit processor and between 1 and 4
  832. gigabytes of physical RAM.
  833. config HIGHMEM64G
  834. bool "64GB"
  835. depends on !M386 && !M486
  836. select X86_PAE
  837. ---help---
  838. Select this if you have a 32-bit processor and more than 4
  839. gigabytes of physical RAM.
  840. endchoice
  841. choice
  842. depends on EXPERIMENTAL
  843. prompt "Memory split" if EMBEDDED
  844. default VMSPLIT_3G
  845. depends on X86_32
  846. ---help---
  847. Select the desired split between kernel and user memory.
  848. If the address range available to the kernel is less than the
  849. physical memory installed, the remaining memory will be available
  850. as "high memory". Accessing high memory is a little more costly
  851. than low memory, as it needs to be mapped into the kernel first.
  852. Note that increasing the kernel address space limits the range
  853. available to user programs, making the address space there
  854. tighter. Selecting anything other than the default 3G/1G split
  855. will also likely make your kernel incompatible with binary-only
  856. kernel modules.
  857. If you are not absolutely sure what you are doing, leave this
  858. option alone!
  859. config VMSPLIT_3G
  860. bool "3G/1G user/kernel split"
  861. config VMSPLIT_3G_OPT
  862. depends on !X86_PAE
  863. bool "3G/1G user/kernel split (for full 1G low memory)"
  864. config VMSPLIT_2G
  865. bool "2G/2G user/kernel split"
  866. config VMSPLIT_2G_OPT
  867. depends on !X86_PAE
  868. bool "2G/2G user/kernel split (for full 2G low memory)"
  869. config VMSPLIT_1G
  870. bool "1G/3G user/kernel split"
  871. endchoice
  872. config PAGE_OFFSET
  873. hex
  874. default 0xB0000000 if VMSPLIT_3G_OPT
  875. default 0x80000000 if VMSPLIT_2G
  876. default 0x78000000 if VMSPLIT_2G_OPT
  877. default 0x40000000 if VMSPLIT_1G
  878. default 0xC0000000
  879. depends on X86_32
  880. config HIGHMEM
  881. def_bool y
  882. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  883. config X86_PAE
  884. bool "PAE (Physical Address Extension) Support"
  885. depends on X86_32 && !HIGHMEM4G
  886. ---help---
  887. PAE is required for NX support, and furthermore enables
  888. larger swapspace support for non-overcommit purposes. It
  889. has the cost of more pagetable lookup overhead, and also
  890. consumes more pagetable space per process.
  891. config ARCH_PHYS_ADDR_T_64BIT
  892. def_bool X86_64 || X86_PAE
  893. config DIRECT_GBPAGES
  894. bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
  895. default y
  896. depends on X86_64
  897. ---help---
  898. Allow the kernel linear mapping to use 1GB pages on CPUs that
  899. support it. This can improve the kernel's performance a tiny bit by
  900. reducing TLB pressure. If in doubt, say "Y".
  901. # Common NUMA Features
  902. config NUMA
  903. bool "Numa Memory Allocation and Scheduler Support"
  904. depends on SMP
  905. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  906. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  907. ---help---
  908. Enable NUMA (Non Uniform Memory Access) support.
  909. The kernel will try to allocate memory used by a CPU on the
  910. local memory controller of the CPU and add some more
  911. NUMA awareness to the kernel.
  912. For 64-bit this is recommended if the system is Intel Core i7
  913. (or later), AMD Opteron, or EM64T NUMA.
  914. For 32-bit this is only needed on (rare) 32-bit-only platforms
  915. that support NUMA topologies, such as NUMAQ / Summit, or if you
  916. boot a 32-bit kernel on a 64-bit NUMA platform.
  917. Otherwise, you should say N.
  918. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  919. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  920. config K8_NUMA
  921. def_bool y
  922. prompt "Old style AMD Opteron NUMA detection"
  923. depends on X86_64 && NUMA && PCI
  924. ---help---
  925. Enable K8 NUMA node topology detection. You should say Y here if
  926. you have a multi processor AMD K8 system. This uses an old
  927. method to read the NUMA configuration directly from the builtin
  928. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  929. instead, which also takes priority if both are compiled in.
  930. config X86_64_ACPI_NUMA
  931. def_bool y
  932. prompt "ACPI NUMA detection"
  933. depends on X86_64 && NUMA && ACPI && PCI
  934. select ACPI_NUMA
  935. ---help---
  936. Enable ACPI SRAT based node topology detection.
  937. # Some NUMA nodes have memory ranges that span
  938. # other nodes. Even though a pfn is valid and
  939. # between a node's start and end pfns, it may not
  940. # reside on that node. See memmap_init_zone()
  941. # for details.
  942. config NODES_SPAN_OTHER_NODES
  943. def_bool y
  944. depends on X86_64_ACPI_NUMA
  945. config NUMA_EMU
  946. bool "NUMA emulation"
  947. depends on X86_64 && NUMA
  948. ---help---
  949. Enable NUMA emulation. A flat machine will be split
  950. into virtual nodes when booted with "numa=fake=N", where N is the
  951. number of nodes. This is only useful for debugging.
  952. config NODES_SHIFT
  953. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  954. range 1 9
  955. default "9" if MAXSMP
  956. default "6" if X86_64
  957. default "4" if X86_NUMAQ
  958. default "3"
  959. depends on NEED_MULTIPLE_NODES
  960. ---help---
  961. Specify the maximum number of NUMA Nodes available on the target
  962. system. Increases memory reserved to accommodate various tables.
  963. config HAVE_ARCH_BOOTMEM
  964. def_bool y
  965. depends on X86_32 && NUMA
  966. config ARCH_HAVE_MEMORY_PRESENT
  967. def_bool y
  968. depends on X86_32 && DISCONTIGMEM
  969. config NEED_NODE_MEMMAP_SIZE
  970. def_bool y
  971. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  972. config HAVE_ARCH_ALLOC_REMAP
  973. def_bool y
  974. depends on X86_32 && NUMA
  975. config ARCH_FLATMEM_ENABLE
  976. def_bool y
  977. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
  978. config ARCH_DISCONTIGMEM_ENABLE
  979. def_bool y
  980. depends on NUMA && X86_32
  981. config ARCH_DISCONTIGMEM_DEFAULT
  982. def_bool y
  983. depends on NUMA && X86_32
  984. config ARCH_SPARSEMEM_DEFAULT
  985. def_bool y
  986. depends on X86_64
  987. config ARCH_SPARSEMEM_ENABLE
  988. def_bool y
  989. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  990. select SPARSEMEM_STATIC if X86_32
  991. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  992. config ARCH_SELECT_MEMORY_MODEL
  993. def_bool y
  994. depends on ARCH_SPARSEMEM_ENABLE
  995. config ARCH_MEMORY_PROBE
  996. def_bool X86_64
  997. depends on MEMORY_HOTPLUG
  998. source "mm/Kconfig"
  999. config HIGHPTE
  1000. bool "Allocate 3rd-level pagetables from highmem"
  1001. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  1002. ---help---
  1003. The VM uses one page table entry for each page of physical memory.
  1004. For systems with a lot of RAM, this can be wasteful of precious
  1005. low memory. Setting this option will put user-space page table
  1006. entries in high memory.
  1007. config X86_CHECK_BIOS_CORRUPTION
  1008. bool "Check for low memory corruption"
  1009. ---help---
  1010. Periodically check for memory corruption in low memory, which
  1011. is suspected to be caused by BIOS. Even when enabled in the
  1012. configuration, it is disabled at runtime. Enable it by
  1013. setting "memory_corruption_check=1" on the kernel command
  1014. line. By default it scans the low 64k of memory every 60
  1015. seconds; see the memory_corruption_check_size and
  1016. memory_corruption_check_period parameters in
  1017. Documentation/kernel-parameters.txt to adjust this.
  1018. When enabled with the default parameters, this option has
  1019. almost no overhead, as it reserves a relatively small amount
  1020. of memory and scans it infrequently. It both detects corruption
  1021. and prevents it from affecting the running system.
  1022. It is, however, intended as a diagnostic tool; if repeatable
  1023. BIOS-originated corruption always affects the same memory,
  1024. you can use memmap= to prevent the kernel from using that
  1025. memory.
  1026. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1027. bool "Set the default setting of memory_corruption_check"
  1028. depends on X86_CHECK_BIOS_CORRUPTION
  1029. default y
  1030. ---help---
  1031. Set whether the default state of memory_corruption_check is
  1032. on or off.
  1033. config X86_RESERVE_LOW_64K
  1034. bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
  1035. default y
  1036. ---help---
  1037. Reserve the first 64K of physical RAM on BIOSes that are known
  1038. to potentially corrupt that memory range. A numbers of BIOSes are
  1039. known to utilize this area during suspend/resume, so it must not
  1040. be used by the kernel.
  1041. Set this to N if you are absolutely sure that you trust the BIOS
  1042. to get all its memory reservations and usages right.
  1043. If you have doubts about the BIOS (e.g. suspend/resume does not
  1044. work or there's kernel crashes after certain hardware hotplug
  1045. events) and it's not AMI or Phoenix, then you might want to enable
  1046. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
  1047. corruption patterns.
  1048. Say Y if unsure.
  1049. config MATH_EMULATION
  1050. bool
  1051. prompt "Math emulation" if X86_32
  1052. ---help---
  1053. Linux can emulate a math coprocessor (used for floating point
  1054. operations) if you don't have one. 486DX and Pentium processors have
  1055. a math coprocessor built in, 486SX and 386 do not, unless you added
  1056. a 487DX or 387, respectively. (The messages during boot time can
  1057. give you some hints here ["man dmesg"].) Everyone needs either a
  1058. coprocessor or this emulation.
  1059. If you don't have a math coprocessor, you need to say Y here; if you
  1060. say Y here even though you have a coprocessor, the coprocessor will
  1061. be used nevertheless. (This behavior can be changed with the kernel
  1062. command line option "no387", which comes handy if your coprocessor
  1063. is broken. Try "man bootparam" or see the documentation of your boot
  1064. loader (lilo or loadlin) about how to pass options to the kernel at
  1065. boot time.) This means that it is a good idea to say Y here if you
  1066. intend to use this kernel on different machines.
  1067. More information about the internals of the Linux math coprocessor
  1068. emulation can be found in <file:arch/x86/math-emu/README>.
  1069. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1070. kernel, it won't hurt.
  1071. config MTRR
  1072. bool "MTRR (Memory Type Range Register) support"
  1073. ---help---
  1074. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1075. the Memory Type Range Registers (MTRRs) may be used to control
  1076. processor access to memory ranges. This is most useful if you have
  1077. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1078. allows bus write transfers to be combined into a larger transfer
  1079. before bursting over the PCI/AGP bus. This can increase performance
  1080. of image write operations 2.5 times or more. Saying Y here creates a
  1081. /proc/mtrr file which may be used to manipulate your processor's
  1082. MTRRs. Typically the X server should use this.
  1083. This code has a reasonably generic interface so that similar
  1084. control registers on other processors can be easily supported
  1085. as well:
  1086. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1087. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1088. these, the ARRs are used to emulate the MTRRs.
  1089. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1090. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1091. write-combining. All of these processors are supported by this code
  1092. and it makes sense to say Y here if you have one of them.
  1093. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1094. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1095. can lead to all sorts of problems, so it's good to say Y here.
  1096. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1097. just add about 9 KB to your kernel.
  1098. See <file:Documentation/x86/mtrr.txt> for more information.
  1099. config MTRR_SANITIZER
  1100. def_bool y
  1101. prompt "MTRR cleanup support"
  1102. depends on MTRR
  1103. ---help---
  1104. Convert MTRR layout from continuous to discrete, so X drivers can
  1105. add writeback entries.
  1106. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1107. The largest mtrr entry size for a continuous block can be set with
  1108. mtrr_chunk_size.
  1109. If unsure, say Y.
  1110. config MTRR_SANITIZER_ENABLE_DEFAULT
  1111. int "MTRR cleanup enable value (0-1)"
  1112. range 0 1
  1113. default "0"
  1114. depends on MTRR_SANITIZER
  1115. ---help---
  1116. Enable mtrr cleanup default value
  1117. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1118. int "MTRR cleanup spare reg num (0-7)"
  1119. range 0 7
  1120. default "1"
  1121. depends on MTRR_SANITIZER
  1122. ---help---
  1123. mtrr cleanup spare entries default, it can be changed via
  1124. mtrr_spare_reg_nr=N on the kernel command line.
  1125. config X86_PAT
  1126. bool
  1127. prompt "x86 PAT support"
  1128. depends on MTRR
  1129. ---help---
  1130. Use PAT attributes to setup page level cache control.
  1131. PATs are the modern equivalents of MTRRs and are much more
  1132. flexible than MTRRs.
  1133. Say N here if you see bootup problems (boot crash, boot hang,
  1134. spontaneous reboots) or a non-working video driver.
  1135. If unsure, say Y.
  1136. config EFI
  1137. bool "EFI runtime service support"
  1138. depends on ACPI
  1139. ---help---
  1140. This enables the kernel to use EFI runtime services that are
  1141. available (such as the EFI variable services).
  1142. This option is only useful on systems that have EFI firmware.
  1143. In addition, you should use the latest ELILO loader available
  1144. at <http://elilo.sourceforge.net> in order to take advantage
  1145. of EFI runtime services. However, even with this option, the
  1146. resultant kernel should continue to boot on existing non-EFI
  1147. platforms.
  1148. config SECCOMP
  1149. def_bool y
  1150. prompt "Enable seccomp to safely compute untrusted bytecode"
  1151. ---help---
  1152. This kernel feature is useful for number crunching applications
  1153. that may need to compute untrusted bytecode during their
  1154. execution. By using pipes or other transports made available to
  1155. the process as file descriptors supporting the read/write
  1156. syscalls, it's possible to isolate those applications in
  1157. their own address space using seccomp. Once seccomp is
  1158. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1159. and the task is only allowed to execute a few safe syscalls
  1160. defined by each seccomp mode.
  1161. If unsure, say Y. Only embedded should say N here.
  1162. config CC_STACKPROTECTOR_ALL
  1163. bool
  1164. config CC_STACKPROTECTOR
  1165. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1166. select CC_STACKPROTECTOR_ALL
  1167. ---help---
  1168. This option turns on the -fstack-protector GCC feature. This
  1169. feature puts, at the beginning of functions, a canary value on
  1170. the stack just before the return address, and validates
  1171. the value just before actually returning. Stack based buffer
  1172. overflows (that need to overwrite this return address) now also
  1173. overwrite the canary, which gets detected and the attack is then
  1174. neutralized via a kernel panic.
  1175. This feature requires gcc version 4.2 or above, or a distribution
  1176. gcc with the feature backported. Older versions are automatically
  1177. detected and for those versions, this configuration option is
  1178. ignored. (and a warning is printed during bootup)
  1179. source kernel/Kconfig.hz
  1180. config KEXEC
  1181. bool "kexec system call"
  1182. ---help---
  1183. kexec is a system call that implements the ability to shutdown your
  1184. current kernel, and to start another kernel. It is like a reboot
  1185. but it is independent of the system firmware. And like a reboot
  1186. you can start any kernel with it, not just Linux.
  1187. The name comes from the similarity to the exec system call.
  1188. It is an ongoing process to be certain the hardware in a machine
  1189. is properly shutdown, so do not be surprised if this code does not
  1190. initially work for you. It may help to enable device hotplugging
  1191. support. As of this writing the exact hardware interface is
  1192. strongly in flux, so no good recommendation can be made.
  1193. config CRASH_DUMP
  1194. bool "kernel crash dumps"
  1195. depends on X86_64 || (X86_32 && HIGHMEM)
  1196. ---help---
  1197. Generate crash dump after being started by kexec.
  1198. This should be normally only set in special crash dump kernels
  1199. which are loaded in the main kernel with kexec-tools into
  1200. a specially reserved region and then later executed after
  1201. a crash by kdump/kexec. The crash dump kernel must be compiled
  1202. to a memory address not used by the main kernel or BIOS using
  1203. PHYSICAL_START, or it must be built as a relocatable image
  1204. (CONFIG_RELOCATABLE=y).
  1205. For more details see Documentation/kdump/kdump.txt
  1206. config KEXEC_JUMP
  1207. bool "kexec jump (EXPERIMENTAL)"
  1208. depends on EXPERIMENTAL
  1209. depends on KEXEC && HIBERNATION
  1210. ---help---
  1211. Jump between original kernel and kexeced kernel and invoke
  1212. code in physical address mode via KEXEC
  1213. config PHYSICAL_START
  1214. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1215. default "0x1000000"
  1216. ---help---
  1217. This gives the physical address where the kernel is loaded.
  1218. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1219. bzImage will decompress itself to above physical address and
  1220. run from there. Otherwise, bzImage will run from the address where
  1221. it has been loaded by the boot loader and will ignore above physical
  1222. address.
  1223. In normal kdump cases one does not have to set/change this option
  1224. as now bzImage can be compiled as a completely relocatable image
  1225. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1226. address. This option is mainly useful for the folks who don't want
  1227. to use a bzImage for capturing the crash dump and want to use a
  1228. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1229. to be specifically compiled to run from a specific memory area
  1230. (normally a reserved region) and this option comes handy.
  1231. So if you are using bzImage for capturing the crash dump,
  1232. leave the value here unchanged to 0x1000000 and set
  1233. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1234. for capturing the crash dump change this value to start of
  1235. the reserved region. In other words, it can be set based on
  1236. the "X" value as specified in the "crashkernel=YM@XM"
  1237. command line boot parameter passed to the panic-ed
  1238. kernel. Please take a look at Documentation/kdump/kdump.txt
  1239. for more details about crash dumps.
  1240. Usage of bzImage for capturing the crash dump is recommended as
  1241. one does not have to build two kernels. Same kernel can be used
  1242. as production kernel and capture kernel. Above option should have
  1243. gone away after relocatable bzImage support is introduced. But it
  1244. is present because there are users out there who continue to use
  1245. vmlinux for dump capture. This option should go away down the
  1246. line.
  1247. Don't change this unless you know what you are doing.
  1248. config RELOCATABLE
  1249. bool "Build a relocatable kernel"
  1250. default y
  1251. ---help---
  1252. This builds a kernel image that retains relocation information
  1253. so it can be loaded someplace besides the default 1MB.
  1254. The relocations tend to make the kernel binary about 10% larger,
  1255. but are discarded at runtime.
  1256. One use is for the kexec on panic case where the recovery kernel
  1257. must live at a different physical address than the primary
  1258. kernel.
  1259. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1260. it has been loaded at and the compile time physical address
  1261. (CONFIG_PHYSICAL_START) is ignored.
  1262. # Relocation on x86-32 needs some additional build support
  1263. config X86_NEED_RELOCS
  1264. def_bool y
  1265. depends on X86_32 && RELOCATABLE
  1266. config PHYSICAL_ALIGN
  1267. hex
  1268. prompt "Alignment value to which kernel should be aligned" if X86_32
  1269. default "0x1000000"
  1270. range 0x2000 0x1000000
  1271. ---help---
  1272. This value puts the alignment restrictions on physical address
  1273. where kernel is loaded and run from. Kernel is compiled for an
  1274. address which meets above alignment restriction.
  1275. If bootloader loads the kernel at a non-aligned address and
  1276. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1277. address aligned to above value and run from there.
  1278. If bootloader loads the kernel at a non-aligned address and
  1279. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1280. load address and decompress itself to the address it has been
  1281. compiled for and run from there. The address for which kernel is
  1282. compiled already meets above alignment restrictions. Hence the
  1283. end result is that kernel runs from a physical address meeting
  1284. above alignment restrictions.
  1285. Don't change this unless you know what you are doing.
  1286. config HOTPLUG_CPU
  1287. bool "Support for hot-pluggable CPUs"
  1288. depends on SMP && HOTPLUG
  1289. ---help---
  1290. Say Y here to allow turning CPUs off and on. CPUs can be
  1291. controlled through /sys/devices/system/cpu.
  1292. ( Note: power management support will enable this option
  1293. automatically on SMP systems. )
  1294. Say N if you want to disable CPU hotplug.
  1295. config COMPAT_VDSO
  1296. def_bool y
  1297. prompt "Compat VDSO support"
  1298. depends on X86_32 || IA32_EMULATION
  1299. ---help---
  1300. Map the 32-bit VDSO to the predictable old-style address too.
  1301. ---help---
  1302. Say N here if you are running a sufficiently recent glibc
  1303. version (2.3.3 or later), to remove the high-mapped
  1304. VDSO mapping and to exclusively use the randomized VDSO.
  1305. If unsure, say Y.
  1306. config CMDLINE_BOOL
  1307. bool "Built-in kernel command line"
  1308. default n
  1309. ---help---
  1310. Allow for specifying boot arguments to the kernel at
  1311. build time. On some systems (e.g. embedded ones), it is
  1312. necessary or convenient to provide some or all of the
  1313. kernel boot arguments with the kernel itself (that is,
  1314. to not rely on the boot loader to provide them.)
  1315. To compile command line arguments into the kernel,
  1316. set this option to 'Y', then fill in the
  1317. the boot arguments in CONFIG_CMDLINE.
  1318. Systems with fully functional boot loaders (i.e. non-embedded)
  1319. should leave this option set to 'N'.
  1320. config CMDLINE
  1321. string "Built-in kernel command string"
  1322. depends on CMDLINE_BOOL
  1323. default ""
  1324. ---help---
  1325. Enter arguments here that should be compiled into the kernel
  1326. image and used at boot time. If the boot loader provides a
  1327. command line at boot time, it is appended to this string to
  1328. form the full kernel command line, when the system boots.
  1329. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1330. change this behavior.
  1331. In most cases, the command line (whether built-in or provided
  1332. by the boot loader) should specify the device for the root
  1333. file system.
  1334. config CMDLINE_OVERRIDE
  1335. bool "Built-in command line overrides boot loader arguments"
  1336. default n
  1337. depends on CMDLINE_BOOL
  1338. ---help---
  1339. Set this option to 'Y' to have the kernel ignore the boot loader
  1340. command line, and use ONLY the built-in command line.
  1341. This is used to work around broken boot loaders. This should
  1342. be set to 'N' under normal conditions.
  1343. endmenu
  1344. config ARCH_ENABLE_MEMORY_HOTPLUG
  1345. def_bool y
  1346. depends on X86_64 || (X86_32 && HIGHMEM)
  1347. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1348. def_bool y
  1349. depends on MEMORY_HOTPLUG
  1350. config HAVE_ARCH_EARLY_PFN_TO_NID
  1351. def_bool X86_64
  1352. depends on NUMA
  1353. menu "Power management and ACPI options"
  1354. config ARCH_HIBERNATION_HEADER
  1355. def_bool y
  1356. depends on X86_64 && HIBERNATION
  1357. source "kernel/power/Kconfig"
  1358. source "drivers/acpi/Kconfig"
  1359. config X86_APM_BOOT
  1360. bool
  1361. default y
  1362. depends on APM || APM_MODULE
  1363. menuconfig APM
  1364. tristate "APM (Advanced Power Management) BIOS support"
  1365. depends on X86_32 && PM_SLEEP
  1366. ---help---
  1367. APM is a BIOS specification for saving power using several different
  1368. techniques. This is mostly useful for battery powered laptops with
  1369. APM compliant BIOSes. If you say Y here, the system time will be
  1370. reset after a RESUME operation, the /proc/apm device will provide
  1371. battery status information, and user-space programs will receive
  1372. notification of APM "events" (e.g. battery status change).
  1373. If you select "Y" here, you can disable actual use of the APM
  1374. BIOS by passing the "apm=off" option to the kernel at boot time.
  1375. Note that the APM support is almost completely disabled for
  1376. machines with more than one CPU.
  1377. In order to use APM, you will need supporting software. For location
  1378. and more information, read <file:Documentation/power/pm.txt> and the
  1379. Battery Powered Linux mini-HOWTO, available from
  1380. <http://www.tldp.org/docs.html#howto>.
  1381. This driver does not spin down disk drives (see the hdparm(8)
  1382. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1383. VESA-compliant "green" monitors.
  1384. This driver does not support the TI 4000M TravelMate and the ACER
  1385. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1386. desktop machines also don't have compliant BIOSes, and this driver
  1387. may cause those machines to panic during the boot phase.
  1388. Generally, if you don't have a battery in your machine, there isn't
  1389. much point in using this driver and you should say N. If you get
  1390. random kernel OOPSes or reboots that don't seem to be related to
  1391. anything, try disabling/enabling this option (or disabling/enabling
  1392. APM in your BIOS).
  1393. Some other things you should try when experiencing seemingly random,
  1394. "weird" problems:
  1395. 1) make sure that you have enough swap space and that it is
  1396. enabled.
  1397. 2) pass the "no-hlt" option to the kernel
  1398. 3) switch on floating point emulation in the kernel and pass
  1399. the "no387" option to the kernel
  1400. 4) pass the "floppy=nodma" option to the kernel
  1401. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1402. all but the first 4 MB of RAM)
  1403. 6) make sure that the CPU is not over clocked.
  1404. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1405. 8) disable the cache from your BIOS settings
  1406. 9) install a fan for the video card or exchange video RAM
  1407. 10) install a better fan for the CPU
  1408. 11) exchange RAM chips
  1409. 12) exchange the motherboard.
  1410. To compile this driver as a module, choose M here: the
  1411. module will be called apm.
  1412. if APM
  1413. config APM_IGNORE_USER_SUSPEND
  1414. bool "Ignore USER SUSPEND"
  1415. ---help---
  1416. This option will ignore USER SUSPEND requests. On machines with a
  1417. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1418. series notebooks, it is necessary to say Y because of a BIOS bug.
  1419. config APM_DO_ENABLE
  1420. bool "Enable PM at boot time"
  1421. ---help---
  1422. Enable APM features at boot time. From page 36 of the APM BIOS
  1423. specification: "When disabled, the APM BIOS does not automatically
  1424. power manage devices, enter the Standby State, enter the Suspend
  1425. State, or take power saving steps in response to CPU Idle calls."
  1426. This driver will make CPU Idle calls when Linux is idle (unless this
  1427. feature is turned off -- see "Do CPU IDLE calls", below). This
  1428. should always save battery power, but more complicated APM features
  1429. will be dependent on your BIOS implementation. You may need to turn
  1430. this option off if your computer hangs at boot time when using APM
  1431. support, or if it beeps continuously instead of suspending. Turn
  1432. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1433. T400CDT. This is off by default since most machines do fine without
  1434. this feature.
  1435. config APM_CPU_IDLE
  1436. bool "Make CPU Idle calls when idle"
  1437. ---help---
  1438. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1439. On some machines, this can activate improved power savings, such as
  1440. a slowed CPU clock rate, when the machine is idle. These idle calls
  1441. are made after the idle loop has run for some length of time (e.g.,
  1442. 333 mS). On some machines, this will cause a hang at boot time or
  1443. whenever the CPU becomes idle. (On machines with more than one CPU,
  1444. this option does nothing.)
  1445. config APM_DISPLAY_BLANK
  1446. bool "Enable console blanking using APM"
  1447. ---help---
  1448. Enable console blanking using the APM. Some laptops can use this to
  1449. turn off the LCD backlight when the screen blanker of the Linux
  1450. virtual console blanks the screen. Note that this is only used by
  1451. the virtual console screen blanker, and won't turn off the backlight
  1452. when using the X Window system. This also doesn't have anything to
  1453. do with your VESA-compliant power-saving monitor. Further, this
  1454. option doesn't work for all laptops -- it might not turn off your
  1455. backlight at all, or it might print a lot of errors to the console,
  1456. especially if you are using gpm.
  1457. config APM_ALLOW_INTS
  1458. bool "Allow interrupts during APM BIOS calls"
  1459. ---help---
  1460. Normally we disable external interrupts while we are making calls to
  1461. the APM BIOS as a measure to lessen the effects of a badly behaving
  1462. BIOS implementation. The BIOS should reenable interrupts if it
  1463. needs to. Unfortunately, some BIOSes do not -- especially those in
  1464. many of the newer IBM Thinkpads. If you experience hangs when you
  1465. suspend, try setting this to Y. Otherwise, say N.
  1466. endif # APM
  1467. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1468. source "drivers/cpuidle/Kconfig"
  1469. source "drivers/idle/Kconfig"
  1470. endmenu
  1471. menu "Bus options (PCI etc.)"
  1472. config PCI
  1473. bool "PCI support"
  1474. default y
  1475. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1476. ---help---
  1477. Find out whether you have a PCI motherboard. PCI is the name of a
  1478. bus system, i.e. the way the CPU talks to the other stuff inside
  1479. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1480. VESA. If you have PCI, say Y, otherwise N.
  1481. choice
  1482. prompt "PCI access mode"
  1483. depends on X86_32 && PCI
  1484. default PCI_GOANY
  1485. ---help---
  1486. On PCI systems, the BIOS can be used to detect the PCI devices and
  1487. determine their configuration. However, some old PCI motherboards
  1488. have BIOS bugs and may crash if this is done. Also, some embedded
  1489. PCI-based systems don't have any BIOS at all. Linux can also try to
  1490. detect the PCI hardware directly without using the BIOS.
  1491. With this option, you can specify how Linux should detect the
  1492. PCI devices. If you choose "BIOS", the BIOS will be used,
  1493. if you choose "Direct", the BIOS won't be used, and if you
  1494. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1495. If you choose "Any", the kernel will try MMCONFIG, then the
  1496. direct access method and falls back to the BIOS if that doesn't
  1497. work. If unsure, go with the default, which is "Any".
  1498. config PCI_GOBIOS
  1499. bool "BIOS"
  1500. config PCI_GOMMCONFIG
  1501. bool "MMConfig"
  1502. config PCI_GODIRECT
  1503. bool "Direct"
  1504. config PCI_GOOLPC
  1505. bool "OLPC"
  1506. depends on OLPC
  1507. config PCI_GOANY
  1508. bool "Any"
  1509. endchoice
  1510. config PCI_BIOS
  1511. def_bool y
  1512. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1513. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1514. config PCI_DIRECT
  1515. def_bool y
  1516. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1517. config PCI_MMCONFIG
  1518. def_bool y
  1519. depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  1520. config PCI_OLPC
  1521. def_bool y
  1522. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1523. config PCI_DOMAINS
  1524. def_bool y
  1525. depends on PCI
  1526. config PCI_MMCONFIG
  1527. bool "Support mmconfig PCI config space access"
  1528. depends on X86_64 && PCI && ACPI
  1529. config DMAR
  1530. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1531. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1532. help
  1533. DMA remapping (DMAR) devices support enables independent address
  1534. translations for Direct Memory Access (DMA) from devices.
  1535. These DMA remapping devices are reported via ACPI tables
  1536. and include PCI device scope covered by these DMA
  1537. remapping devices.
  1538. config DMAR_DEFAULT_ON
  1539. def_bool y
  1540. prompt "Enable DMA Remapping Devices by default"
  1541. depends on DMAR
  1542. help
  1543. Selecting this option will enable a DMAR device at boot time if
  1544. one is found. If this option is not selected, DMAR support can
  1545. be enabled by passing intel_iommu=on to the kernel. It is
  1546. recommended you say N here while the DMAR code remains
  1547. experimental.
  1548. config DMAR_GFX_WA
  1549. def_bool y
  1550. prompt "Support for Graphics workaround"
  1551. depends on DMAR
  1552. ---help---
  1553. Current Graphics drivers tend to use physical address
  1554. for DMA and avoid using DMA APIs. Setting this config
  1555. option permits the IOMMU driver to set a unity map for
  1556. all the OS-visible memory. Hence the driver can continue
  1557. to use physical addresses for DMA.
  1558. config DMAR_FLOPPY_WA
  1559. def_bool y
  1560. depends on DMAR
  1561. ---help---
  1562. Floppy disk drivers are know to bypass DMA API calls
  1563. thereby failing to work when IOMMU is enabled. This
  1564. workaround will setup a 1:1 mapping for the first
  1565. 16M to make floppy (an ISA device) work.
  1566. config INTR_REMAP
  1567. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1568. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1569. ---help---
  1570. Supports Interrupt remapping for IO-APIC and MSI devices.
  1571. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1572. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1573. source "drivers/pci/pcie/Kconfig"
  1574. source "drivers/pci/Kconfig"
  1575. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1576. config ISA_DMA_API
  1577. def_bool y
  1578. if X86_32
  1579. config ISA
  1580. bool "ISA support"
  1581. ---help---
  1582. Find out whether you have ISA slots on your motherboard. ISA is the
  1583. name of a bus system, i.e. the way the CPU talks to the other stuff
  1584. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1585. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1586. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1587. config EISA
  1588. bool "EISA support"
  1589. depends on ISA
  1590. ---help---
  1591. The Extended Industry Standard Architecture (EISA) bus was
  1592. developed as an open alternative to the IBM MicroChannel bus.
  1593. The EISA bus provided some of the features of the IBM MicroChannel
  1594. bus while maintaining backward compatibility with cards made for
  1595. the older ISA bus. The EISA bus saw limited use between 1988 and
  1596. 1995 when it was made obsolete by the PCI bus.
  1597. Say Y here if you are building a kernel for an EISA-based machine.
  1598. Otherwise, say N.
  1599. source "drivers/eisa/Kconfig"
  1600. config MCA
  1601. bool "MCA support"
  1602. ---help---
  1603. MicroChannel Architecture is found in some IBM PS/2 machines and
  1604. laptops. It is a bus system similar to PCI or ISA. See
  1605. <file:Documentation/mca.txt> (and especially the web page given
  1606. there) before attempting to build an MCA bus kernel.
  1607. source "drivers/mca/Kconfig"
  1608. config SCx200
  1609. tristate "NatSemi SCx200 support"
  1610. ---help---
  1611. This provides basic support for National Semiconductor's
  1612. (now AMD's) Geode processors. The driver probes for the
  1613. PCI-IDs of several on-chip devices, so its a good dependency
  1614. for other scx200_* drivers.
  1615. If compiled as a module, the driver is named scx200.
  1616. config SCx200HR_TIMER
  1617. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1618. depends on SCx200 && GENERIC_TIME
  1619. default y
  1620. ---help---
  1621. This driver provides a clocksource built upon the on-chip
  1622. 27MHz high-resolution timer. Its also a workaround for
  1623. NSC Geode SC-1100's buggy TSC, which loses time when the
  1624. processor goes idle (as is done by the scheduler). The
  1625. other workaround is idle=poll boot option.
  1626. config GEODE_MFGPT_TIMER
  1627. def_bool y
  1628. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1629. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1630. ---help---
  1631. This driver provides a clock event source based on the MFGPT
  1632. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1633. MFGPTs have a better resolution and max interval than the
  1634. generic PIT, and are suitable for use as high-res timers.
  1635. config OLPC
  1636. bool "One Laptop Per Child support"
  1637. default n
  1638. ---help---
  1639. Add support for detecting the unique features of the OLPC
  1640. XO hardware.
  1641. endif # X86_32
  1642. config K8_NB
  1643. def_bool y
  1644. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1645. source "drivers/pcmcia/Kconfig"
  1646. source "drivers/pci/hotplug/Kconfig"
  1647. endmenu
  1648. menu "Executable file formats / Emulations"
  1649. source "fs/Kconfig.binfmt"
  1650. config IA32_EMULATION
  1651. bool "IA32 Emulation"
  1652. depends on X86_64
  1653. select COMPAT_BINFMT_ELF
  1654. ---help---
  1655. Include code to run 32-bit programs under a 64-bit kernel. You should
  1656. likely turn this on, unless you're 100% sure that you don't have any
  1657. 32-bit programs left.
  1658. config IA32_AOUT
  1659. tristate "IA32 a.out support"
  1660. depends on IA32_EMULATION
  1661. ---help---
  1662. Support old a.out binaries in the 32bit emulation.
  1663. config COMPAT
  1664. def_bool y
  1665. depends on IA32_EMULATION
  1666. config COMPAT_FOR_U64_ALIGNMENT
  1667. def_bool COMPAT
  1668. depends on X86_64
  1669. config SYSVIPC_COMPAT
  1670. def_bool y
  1671. depends on COMPAT && SYSVIPC
  1672. endmenu
  1673. config HAVE_ATOMIC_IOMAP
  1674. def_bool y
  1675. depends on X86_32
  1676. source "net/Kconfig"
  1677. source "drivers/Kconfig"
  1678. source "drivers/firmware/Kconfig"
  1679. source "fs/Kconfig"
  1680. source "arch/x86/Kconfig.debug"
  1681. source "security/Kconfig"
  1682. source "crypto/Kconfig"
  1683. source "arch/x86/kvm/Kconfig"
  1684. source "lib/Kconfig"