Kconfig 67 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_FTRACE_MCOUNT_RECORD
  31. select HAVE_DYNAMIC_FTRACE
  32. select HAVE_FUNCTION_TRACER
  33. select HAVE_FUNCTION_GRAPH_TRACER
  34. select HAVE_FUNCTION_GRAPH_FP_TEST
  35. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  36. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  37. select HAVE_SYSCALL_TRACEPOINTS
  38. select HAVE_KVM
  39. select HAVE_ARCH_KGDB
  40. select HAVE_ARCH_TRACEHOOK
  41. select HAVE_GENERIC_DMA_COHERENT if X86_32
  42. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  43. select USER_STACKTRACE_SUPPORT
  44. select HAVE_DMA_API_DEBUG
  45. select HAVE_KERNEL_GZIP
  46. select HAVE_KERNEL_BZIP2
  47. select HAVE_KERNEL_LZMA
  48. select HAVE_HW_BREAKPOINT
  49. select HAVE_ARCH_KMEMCHECK
  50. select HAVE_USER_RETURN_NOTIFIER
  51. config OUTPUT_FORMAT
  52. string
  53. default "elf32-i386" if X86_32
  54. default "elf64-x86-64" if X86_64
  55. config ARCH_DEFCONFIG
  56. string
  57. default "arch/x86/configs/i386_defconfig" if X86_32
  58. default "arch/x86/configs/x86_64_defconfig" if X86_64
  59. config GENERIC_TIME
  60. def_bool y
  61. config GENERIC_CMOS_UPDATE
  62. def_bool y
  63. config CLOCKSOURCE_WATCHDOG
  64. def_bool y
  65. config GENERIC_CLOCKEVENTS
  66. def_bool y
  67. config GENERIC_CLOCKEVENTS_BROADCAST
  68. def_bool y
  69. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  70. config LOCKDEP_SUPPORT
  71. def_bool y
  72. config STACKTRACE_SUPPORT
  73. def_bool y
  74. config HAVE_LATENCYTOP_SUPPORT
  75. def_bool y
  76. config MMU
  77. def_bool y
  78. config ZONE_DMA
  79. def_bool y
  80. config SBUS
  81. bool
  82. config GENERIC_ISA_DMA
  83. def_bool y
  84. config GENERIC_IOMAP
  85. def_bool y
  86. config GENERIC_BUG
  87. def_bool y
  88. depends on BUG
  89. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  90. config GENERIC_BUG_RELATIVE_POINTERS
  91. bool
  92. config GENERIC_HWEIGHT
  93. def_bool y
  94. config GENERIC_GPIO
  95. bool
  96. config ARCH_MAY_HAVE_PC_FDC
  97. def_bool y
  98. config RWSEM_GENERIC_SPINLOCK
  99. def_bool !X86_XADD
  100. config RWSEM_XCHGADD_ALGORITHM
  101. def_bool X86_XADD
  102. config ARCH_HAS_CPU_IDLE_WAIT
  103. def_bool y
  104. config GENERIC_CALIBRATE_DELAY
  105. def_bool y
  106. config GENERIC_TIME_VSYSCALL
  107. bool
  108. default X86_64
  109. config ARCH_HAS_CPU_RELAX
  110. def_bool y
  111. config ARCH_HAS_DEFAULT_IDLE
  112. def_bool y
  113. config ARCH_HAS_CACHE_LINE_SIZE
  114. def_bool y
  115. config HAVE_SETUP_PER_CPU_AREA
  116. def_bool y
  117. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  118. def_bool y
  119. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  120. def_bool y
  121. config HAVE_CPUMASK_OF_CPU_MAP
  122. def_bool X86_64_SMP
  123. config ARCH_HIBERNATION_POSSIBLE
  124. def_bool y
  125. config ARCH_SUSPEND_POSSIBLE
  126. def_bool y
  127. config ZONE_DMA32
  128. bool
  129. default X86_64
  130. config ARCH_POPULATES_NODE_MAP
  131. def_bool y
  132. config AUDIT_ARCH
  133. bool
  134. default X86_64
  135. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  136. def_bool y
  137. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  138. def_bool y
  139. config HAVE_INTEL_TXT
  140. def_bool y
  141. depends on EXPERIMENTAL && DMAR && ACPI
  142. # Use the generic interrupt handling code in kernel/irq/:
  143. config GENERIC_HARDIRQS
  144. bool
  145. default y
  146. config GENERIC_HARDIRQS_NO__DO_IRQ
  147. def_bool y
  148. config GENERIC_IRQ_PROBE
  149. bool
  150. default y
  151. config GENERIC_PENDING_IRQ
  152. bool
  153. depends on GENERIC_HARDIRQS && SMP
  154. default y
  155. config USE_GENERIC_SMP_HELPERS
  156. def_bool y
  157. depends on SMP
  158. config X86_32_SMP
  159. def_bool y
  160. depends on X86_32 && SMP
  161. config X86_64_SMP
  162. def_bool y
  163. depends on X86_64 && SMP
  164. config X86_HT
  165. bool
  166. depends on SMP
  167. default y
  168. config X86_TRAMPOLINE
  169. bool
  170. depends on SMP || (64BIT && ACPI_SLEEP)
  171. default y
  172. config X86_32_LAZY_GS
  173. def_bool y
  174. depends on X86_32 && !CC_STACKPROTECTOR
  175. config KTIME_SCALAR
  176. def_bool X86_32
  177. source "init/Kconfig"
  178. source "kernel/Kconfig.freezer"
  179. menu "Processor type and features"
  180. source "kernel/time/Kconfig"
  181. config SMP
  182. bool "Symmetric multi-processing support"
  183. ---help---
  184. This enables support for systems with more than one CPU. If you have
  185. a system with only one CPU, like most personal computers, say N. If
  186. you have a system with more than one CPU, say Y.
  187. If you say N here, the kernel will run on single and multiprocessor
  188. machines, but will use only one CPU of a multiprocessor machine. If
  189. you say Y here, the kernel will run on many, but not all,
  190. singleprocessor machines. On a singleprocessor machine, the kernel
  191. will run faster if you say N here.
  192. Note that if you say Y here and choose architecture "586" or
  193. "Pentium" under "Processor family", the kernel will not work on 486
  194. architectures. Similarly, multiprocessor kernels for the "PPro"
  195. architecture may not work on all Pentium based boards.
  196. People using multiprocessor machines who say Y here should also say
  197. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  198. Management" code will be disabled if you say Y here.
  199. See also <file:Documentation/i386/IO-APIC.txt>,
  200. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  201. <http://www.tldp.org/docs.html#howto>.
  202. If you don't know what to do here, say N.
  203. config X86_X2APIC
  204. bool "Support x2apic"
  205. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  206. ---help---
  207. This enables x2apic support on CPUs that have this feature.
  208. This allows 32-bit apic IDs (so it can support very large systems),
  209. and accesses the local apic via MSRs not via mmio.
  210. If you don't know what to do here, say N.
  211. config SPARSE_IRQ
  212. bool "Support sparse irq numbering"
  213. depends on PCI_MSI || HT_IRQ
  214. ---help---
  215. This enables support for sparse irqs. This is useful for distro
  216. kernels that want to define a high CONFIG_NR_CPUS value but still
  217. want to have low kernel memory footprint on smaller machines.
  218. ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
  219. out the irq_desc[] array in a more NUMA-friendly way. )
  220. If you don't know what to do here, say N.
  221. config NUMA_IRQ_DESC
  222. def_bool y
  223. depends on SPARSE_IRQ && NUMA
  224. config X86_MPPARSE
  225. bool "Enable MPS table" if ACPI
  226. default y
  227. depends on X86_LOCAL_APIC
  228. ---help---
  229. For old smp systems that do not have proper acpi support. Newer systems
  230. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  231. config X86_BIGSMP
  232. bool "Support for big SMP systems with more than 8 CPUs"
  233. depends on X86_32 && SMP
  234. ---help---
  235. This option is needed for the systems that have more than 8 CPUs
  236. if X86_32
  237. config X86_EXTENDED_PLATFORM
  238. bool "Support for extended (non-PC) x86 platforms"
  239. default y
  240. ---help---
  241. If you disable this option then the kernel will only support
  242. standard PC platforms. (which covers the vast majority of
  243. systems out there.)
  244. If you enable this option then you'll be able to select support
  245. for the following (non-PC) 32 bit x86 platforms:
  246. AMD Elan
  247. NUMAQ (IBM/Sequent)
  248. RDC R-321x SoC
  249. SGI 320/540 (Visual Workstation)
  250. Summit/EXA (IBM x440)
  251. Unisys ES7000 IA32 series
  252. Moorestown MID devices
  253. If you have one of these systems, or if you want to build a
  254. generic distribution kernel, say Y here - otherwise say N.
  255. endif
  256. if X86_64
  257. config X86_EXTENDED_PLATFORM
  258. bool "Support for extended (non-PC) x86 platforms"
  259. default y
  260. ---help---
  261. If you disable this option then the kernel will only support
  262. standard PC platforms. (which covers the vast majority of
  263. systems out there.)
  264. If you enable this option then you'll be able to select support
  265. for the following (non-PC) 64 bit x86 platforms:
  266. ScaleMP vSMP
  267. SGI Ultraviolet
  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. # This is an alphabetically sorted list of 64 bit extended platforms
  272. # Please maintain the alphabetic order if and when there are additions
  273. config X86_VSMP
  274. bool "ScaleMP vSMP"
  275. select PARAVIRT
  276. depends on X86_64 && PCI
  277. depends on X86_EXTENDED_PLATFORM
  278. ---help---
  279. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  280. supposed to run on these EM64T-based machines. Only choose this option
  281. if you have one of these machines.
  282. config X86_UV
  283. bool "SGI Ultraviolet"
  284. depends on X86_64
  285. depends on X86_EXTENDED_PLATFORM
  286. depends on NUMA
  287. depends on X86_X2APIC
  288. ---help---
  289. This option is needed in order to support SGI Ultraviolet systems.
  290. If you don't have one of these, you should say N here.
  291. # Following is an alphabetically sorted list of 32 bit extended platforms
  292. # Please maintain the alphabetic order if and when there are additions
  293. config X86_ELAN
  294. bool "AMD Elan"
  295. depends on X86_32
  296. depends on X86_EXTENDED_PLATFORM
  297. ---help---
  298. Select this for an AMD Elan processor.
  299. Do not use this option for K6/Athlon/Opteron processors!
  300. If unsure, choose "PC-compatible" instead.
  301. config X86_MRST
  302. bool "Moorestown MID platform"
  303. depends on X86_32
  304. depends on X86_EXTENDED_PLATFORM
  305. ---help---
  306. Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
  307. Internet Device(MID) platform. Moorestown consists of two chips:
  308. Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
  309. Unlike standard x86 PCs, Moorestown does not have many legacy devices
  310. nor standard legacy replacement devices/features. e.g. Moorestown does
  311. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  312. config X86_RDC321X
  313. bool "RDC R-321x SoC"
  314. depends on X86_32
  315. depends on X86_EXTENDED_PLATFORM
  316. select M486
  317. select X86_REBOOTFIXUPS
  318. ---help---
  319. This option is needed for RDC R-321x system-on-chip, also known
  320. as R-8610-(G).
  321. If you don't have one of these chips, you should say N here.
  322. config X86_32_NON_STANDARD
  323. bool "Support non-standard 32-bit SMP architectures"
  324. depends on X86_32 && SMP
  325. depends on X86_EXTENDED_PLATFORM
  326. ---help---
  327. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  328. subarchitectures. It is intended for a generic binary kernel.
  329. if you select them all, kernel will probe it one by one. and will
  330. fallback to default.
  331. # Alphabetically sorted list of Non standard 32 bit platforms
  332. config X86_NUMAQ
  333. bool "NUMAQ (IBM/Sequent)"
  334. depends on X86_32_NON_STANDARD
  335. select NUMA
  336. select X86_MPPARSE
  337. ---help---
  338. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  339. NUMA multiquad box. This changes the way that processors are
  340. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  341. of Flat Logical. You will need a new lynxer.elf file to flash your
  342. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  343. config X86_SUPPORTS_MEMORY_FAILURE
  344. bool
  345. # MCE code calls memory_failure():
  346. depends on X86_MCE
  347. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  348. depends on !X86_NUMAQ
  349. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  350. depends on X86_64 || !SPARSEMEM
  351. select ARCH_SUPPORTS_MEMORY_FAILURE
  352. default y
  353. config X86_VISWS
  354. bool "SGI 320/540 (Visual Workstation)"
  355. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  356. depends on X86_32_NON_STANDARD
  357. ---help---
  358. The SGI Visual Workstation series is an IA32-based workstation
  359. based on SGI systems chips with some legacy PC hardware attached.
  360. Say Y here to create a kernel to run on the SGI 320 or 540.
  361. A kernel compiled for the Visual Workstation will run on general
  362. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  363. config X86_SUMMIT
  364. bool "Summit/EXA (IBM x440)"
  365. depends on X86_32_NON_STANDARD
  366. ---help---
  367. This option is needed for IBM systems that use the Summit/EXA chipset.
  368. In particular, it is needed for the x440.
  369. config X86_ES7000
  370. bool "Unisys ES7000 IA32 series"
  371. depends on X86_32_NON_STANDARD && X86_BIGSMP
  372. ---help---
  373. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  374. supposed to run on an IA32-based Unisys ES7000 system.
  375. config SCHED_OMIT_FRAME_POINTER
  376. def_bool y
  377. prompt "Single-depth WCHAN output"
  378. depends on X86
  379. ---help---
  380. Calculate simpler /proc/<PID>/wchan values. If this option
  381. is disabled then wchan values will recurse back to the
  382. caller function. This provides more accurate wchan values,
  383. at the expense of slightly more scheduling overhead.
  384. If in doubt, say "Y".
  385. menuconfig PARAVIRT_GUEST
  386. bool "Paravirtualized guest support"
  387. ---help---
  388. Say Y here to get to see options related to running Linux under
  389. various hypervisors. This option alone does not add any kernel code.
  390. If you say N, all options in this submenu will be skipped and disabled.
  391. if PARAVIRT_GUEST
  392. source "arch/x86/xen/Kconfig"
  393. config VMI
  394. bool "VMI Guest support (DEPRECATED)"
  395. select PARAVIRT
  396. depends on X86_32
  397. ---help---
  398. VMI provides a paravirtualized interface to the VMware ESX server
  399. (it could be used by other hypervisors in theory too, but is not
  400. at the moment), by linking the kernel to a GPL-ed ROM module
  401. provided by the hypervisor.
  402. As of September 2009, VMware has started a phased retirement
  403. of this feature from VMware's products. Please see
  404. feature-removal-schedule.txt for details. If you are
  405. planning to enable this option, please note that you cannot
  406. live migrate a VMI enabled VM to a future VMware product,
  407. which doesn't support VMI. So if you expect your kernel to
  408. seamlessly migrate to newer VMware products, keep this
  409. disabled.
  410. config KVM_CLOCK
  411. bool "KVM paravirtualized clock"
  412. select PARAVIRT
  413. select PARAVIRT_CLOCK
  414. ---help---
  415. Turning on this option will allow you to run a paravirtualized clock
  416. when running over the KVM hypervisor. Instead of relying on a PIT
  417. (or probably other) emulation by the underlying device model, the host
  418. provides the guest with timing infrastructure such as time of day, and
  419. system time
  420. config KVM_GUEST
  421. bool "KVM Guest support"
  422. select PARAVIRT
  423. ---help---
  424. This option enables various optimizations for running under the KVM
  425. hypervisor.
  426. source "arch/x86/lguest/Kconfig"
  427. config PARAVIRT
  428. bool "Enable paravirtualization code"
  429. ---help---
  430. This changes the kernel so it can modify itself when it is run
  431. under a hypervisor, potentially improving performance significantly
  432. over full virtualization. However, when run without a hypervisor
  433. the kernel is theoretically slower and slightly larger.
  434. config PARAVIRT_SPINLOCKS
  435. bool "Paravirtualization layer for spinlocks"
  436. depends on PARAVIRT && SMP && EXPERIMENTAL
  437. ---help---
  438. Paravirtualized spinlocks allow a pvops backend to replace the
  439. spinlock implementation with something virtualization-friendly
  440. (for example, block the virtual CPU rather than spinning).
  441. Unfortunately the downside is an up to 5% performance hit on
  442. native kernels, with various workloads.
  443. If you are unsure how to answer this question, answer N.
  444. config PARAVIRT_CLOCK
  445. bool
  446. default n
  447. endif
  448. config PARAVIRT_DEBUG
  449. bool "paravirt-ops debugging"
  450. depends on PARAVIRT && DEBUG_KERNEL
  451. ---help---
  452. Enable to debug paravirt_ops internals. Specifically, BUG if
  453. a paravirt_op is missing when it is called.
  454. config MEMTEST
  455. bool "Memtest"
  456. ---help---
  457. This option adds a kernel parameter 'memtest', which allows memtest
  458. to be set.
  459. memtest=0, mean disabled; -- default
  460. memtest=1, mean do 1 test pattern;
  461. ...
  462. memtest=4, mean do 4 test patterns.
  463. If you are unsure how to answer this question, answer N.
  464. config X86_SUMMIT_NUMA
  465. def_bool y
  466. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  467. config X86_CYCLONE_TIMER
  468. def_bool y
  469. depends on X86_32_NON_STANDARD
  470. source "arch/x86/Kconfig.cpu"
  471. config HPET_TIMER
  472. def_bool X86_64
  473. prompt "HPET Timer Support" if X86_32
  474. ---help---
  475. Use the IA-PC HPET (High Precision Event Timer) to manage
  476. time in preference to the PIT and RTC, if a HPET is
  477. present.
  478. HPET is the next generation timer replacing legacy 8254s.
  479. The HPET provides a stable time base on SMP
  480. systems, unlike the TSC, but it is more expensive to access,
  481. as it is off-chip. You can find the HPET spec at
  482. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  483. You can safely choose Y here. However, HPET will only be
  484. activated if the platform and the BIOS support this feature.
  485. Otherwise the 8254 will be used for timing services.
  486. Choose N to continue using the legacy 8254 timer.
  487. config HPET_EMULATE_RTC
  488. def_bool y
  489. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  490. # Mark as embedded because too many people got it wrong.
  491. # The code disables itself when not needed.
  492. config DMI
  493. default y
  494. bool "Enable DMI scanning" if EMBEDDED
  495. ---help---
  496. Enabled scanning of DMI to identify machine quirks. Say Y
  497. here unless you have verified that your setup is not
  498. affected by entries in the DMI blacklist. Required by PNP
  499. BIOS code.
  500. config GART_IOMMU
  501. bool "GART IOMMU support" if EMBEDDED
  502. default y
  503. select SWIOTLB
  504. depends on X86_64 && PCI
  505. ---help---
  506. Support for full DMA access of devices with 32bit memory access only
  507. on systems with more than 3GB. This is usually needed for USB,
  508. sound, many IDE/SATA chipsets and some other devices.
  509. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  510. based hardware IOMMU and a software bounce buffer based IOMMU used
  511. on Intel systems and as fallback.
  512. The code is only active when needed (enough memory and limited
  513. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  514. too.
  515. config CALGARY_IOMMU
  516. bool "IBM Calgary IOMMU support"
  517. select SWIOTLB
  518. depends on X86_64 && PCI && EXPERIMENTAL
  519. ---help---
  520. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  521. systems. Needed to run systems with more than 3GB of memory
  522. properly with 32-bit PCI devices that do not support DAC
  523. (Double Address Cycle). Calgary also supports bus level
  524. isolation, where all DMAs pass through the IOMMU. This
  525. prevents them from going anywhere except their intended
  526. destination. This catches hard-to-find kernel bugs and
  527. mis-behaving drivers and devices that do not use the DMA-API
  528. properly to set up their DMA buffers. The IOMMU can be
  529. turned off at boot time with the iommu=off parameter.
  530. Normally the kernel will make the right choice by itself.
  531. If unsure, say Y.
  532. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  533. def_bool y
  534. prompt "Should Calgary be enabled by default?"
  535. depends on CALGARY_IOMMU
  536. ---help---
  537. Should Calgary be enabled by default? if you choose 'y', Calgary
  538. will be used (if it exists). If you choose 'n', Calgary will not be
  539. used even if it exists. If you choose 'n' and would like to use
  540. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  541. If unsure, say Y.
  542. config AMD_IOMMU
  543. bool "AMD IOMMU support"
  544. select SWIOTLB
  545. select PCI_MSI
  546. depends on X86_64 && PCI && ACPI
  547. ---help---
  548. With this option you can enable support for AMD IOMMU hardware in
  549. your system. An IOMMU is a hardware component which provides
  550. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  551. can isolate the the DMA memory of different devices and protect the
  552. system from misbehaving device drivers or hardware.
  553. You can find out if your system has an AMD IOMMU if you look into
  554. your BIOS for an option to enable it or if you have an IVRS ACPI
  555. table.
  556. config AMD_IOMMU_STATS
  557. bool "Export AMD IOMMU statistics to debugfs"
  558. depends on AMD_IOMMU
  559. select DEBUG_FS
  560. ---help---
  561. This option enables code in the AMD IOMMU driver to collect various
  562. statistics about whats happening in the driver and exports that
  563. information to userspace via debugfs.
  564. If unsure, say N.
  565. # need this always selected by IOMMU for the VIA workaround
  566. config SWIOTLB
  567. def_bool y if X86_64
  568. ---help---
  569. Support for software bounce buffers used on x86-64 systems
  570. which don't have a hardware IOMMU (e.g. the current generation
  571. of Intel's x86-64 CPUs). Using this PCI devices which can only
  572. access 32-bits of memory can be used on systems with more than
  573. 3 GB of memory. If unsure, say Y.
  574. config IOMMU_HELPER
  575. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  576. config IOMMU_API
  577. def_bool (AMD_IOMMU || DMAR)
  578. config MAXSMP
  579. bool "Configure Maximum number of SMP Processors and NUMA Nodes"
  580. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  581. select CPUMASK_OFFSTACK
  582. default n
  583. ---help---
  584. Configure maximum number of CPUS and NUMA Nodes for this architecture.
  585. If unsure, say N.
  586. config NR_CPUS
  587. int "Maximum number of CPUs" if SMP && !MAXSMP
  588. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  589. range 2 512 if SMP && !MAXSMP
  590. default "1" if !SMP
  591. default "4096" if MAXSMP
  592. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  593. default "8" if SMP
  594. ---help---
  595. This allows you to specify the maximum number of CPUs which this
  596. kernel will support. The maximum supported value is 512 and the
  597. minimum value which makes sense is 2.
  598. This is purely to save memory - each supported CPU adds
  599. approximately eight kilobytes to the kernel image.
  600. config SCHED_SMT
  601. bool "SMT (Hyperthreading) scheduler support"
  602. depends on X86_HT
  603. ---help---
  604. SMT scheduler support improves the CPU scheduler's decision making
  605. when dealing with Intel Pentium 4 chips with HyperThreading at a
  606. cost of slightly increased overhead in some places. If unsure say
  607. N here.
  608. config SCHED_MC
  609. def_bool y
  610. prompt "Multi-core scheduler support"
  611. depends on X86_HT
  612. ---help---
  613. Multi-core scheduler support improves the CPU scheduler's decision
  614. making when dealing with multi-core CPU chips at a cost of slightly
  615. increased overhead in some places. If unsure say N here.
  616. source "kernel/Kconfig.preempt"
  617. config X86_UP_APIC
  618. bool "Local APIC support on uniprocessors"
  619. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  620. ---help---
  621. A local APIC (Advanced Programmable Interrupt Controller) is an
  622. integrated interrupt controller in the CPU. If you have a single-CPU
  623. system which has a processor with a local APIC, you can say Y here to
  624. enable and use it. If you say Y here even though your machine doesn't
  625. have a local APIC, then the kernel will still run with no slowdown at
  626. all. The local APIC supports CPU-generated self-interrupts (timer,
  627. performance counters), and the NMI watchdog which detects hard
  628. lockups.
  629. config X86_UP_IOAPIC
  630. bool "IO-APIC support on uniprocessors"
  631. depends on X86_UP_APIC
  632. ---help---
  633. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  634. SMP-capable replacement for PC-style interrupt controllers. Most
  635. SMP systems and many recent uniprocessor systems have one.
  636. If you have a single-CPU system with an IO-APIC, you can say Y here
  637. to use it. If you say Y here even though your machine doesn't have
  638. an IO-APIC, then the kernel will still run with no slowdown at all.
  639. config X86_LOCAL_APIC
  640. def_bool y
  641. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  642. config X86_IO_APIC
  643. def_bool y
  644. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  645. config X86_VISWS_APIC
  646. def_bool y
  647. depends on X86_32 && X86_VISWS
  648. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  649. bool "Reroute for broken boot IRQs"
  650. default n
  651. depends on X86_IO_APIC
  652. ---help---
  653. This option enables a workaround that fixes a source of
  654. spurious interrupts. This is recommended when threaded
  655. interrupt handling is used on systems where the generation of
  656. superfluous "boot interrupts" cannot be disabled.
  657. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  658. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  659. kernel does during interrupt handling). On chipsets where this
  660. boot IRQ generation cannot be disabled, this workaround keeps
  661. the original IRQ line masked so that only the equivalent "boot
  662. IRQ" is delivered to the CPUs. The workaround also tells the
  663. kernel to set up the IRQ handler on the boot IRQ line. In this
  664. way only one interrupt is delivered to the kernel. Otherwise
  665. the spurious second interrupt may cause the kernel to bring
  666. down (vital) interrupt lines.
  667. Only affects "broken" chipsets. Interrupt sharing may be
  668. increased on these systems.
  669. config X86_MCE
  670. bool "Machine Check / overheating reporting"
  671. ---help---
  672. Machine Check support allows the processor to notify the
  673. kernel if it detects a problem (e.g. overheating, data corruption).
  674. The action the kernel takes depends on the severity of the problem,
  675. ranging from warning messages to halting the machine.
  676. config X86_MCE_INTEL
  677. def_bool y
  678. prompt "Intel MCE features"
  679. depends on X86_MCE && X86_LOCAL_APIC
  680. ---help---
  681. Additional support for intel specific MCE features such as
  682. the thermal monitor.
  683. config X86_MCE_AMD
  684. def_bool y
  685. prompt "AMD MCE features"
  686. depends on X86_MCE && X86_LOCAL_APIC
  687. ---help---
  688. Additional support for AMD specific MCE features such as
  689. the DRAM Error Threshold.
  690. config X86_ANCIENT_MCE
  691. def_bool n
  692. depends on X86_32 && X86_MCE
  693. prompt "Support for old Pentium 5 / WinChip machine checks"
  694. ---help---
  695. Include support for machine check handling on old Pentium 5 or WinChip
  696. systems. These typically need to be enabled explicitely on the command
  697. line.
  698. config X86_MCE_THRESHOLD
  699. depends on X86_MCE_AMD || X86_MCE_INTEL
  700. bool
  701. default y
  702. config X86_MCE_INJECT
  703. depends on X86_MCE
  704. tristate "Machine check injector support"
  705. ---help---
  706. Provide support for injecting machine checks for testing purposes.
  707. If you don't know what a machine check is and you don't do kernel
  708. QA it is safe to say n.
  709. config X86_THERMAL_VECTOR
  710. def_bool y
  711. depends on X86_MCE_INTEL
  712. config VM86
  713. bool "Enable VM86 support" if EMBEDDED
  714. default y
  715. depends on X86_32
  716. ---help---
  717. This option is required by programs like DOSEMU to run 16-bit legacy
  718. code on X86 processors. It also may be needed by software like
  719. XFree86 to initialize some video cards via BIOS. Disabling this
  720. option saves about 6k.
  721. config TOSHIBA
  722. tristate "Toshiba Laptop support"
  723. depends on X86_32
  724. ---help---
  725. This adds a driver to safely access the System Management Mode of
  726. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  727. not work on models with a Phoenix BIOS. The System Management Mode
  728. is used to set the BIOS and power saving options on Toshiba portables.
  729. For information on utilities to make use of this driver see the
  730. Toshiba Linux utilities web site at:
  731. <http://www.buzzard.org.uk/toshiba/>.
  732. Say Y if you intend to run this kernel on a Toshiba portable.
  733. Say N otherwise.
  734. config I8K
  735. tristate "Dell laptop support"
  736. ---help---
  737. This adds a driver to safely access the System Management Mode
  738. of the CPU on the Dell Inspiron 8000. The System Management Mode
  739. is used to read cpu temperature and cooling fan status and to
  740. control the fans on the I8K portables.
  741. This driver has been tested only on the Inspiron 8000 but it may
  742. also work with other Dell laptops. You can force loading on other
  743. models by passing the parameter `force=1' to the module. Use at
  744. your own risk.
  745. For information on utilities to make use of this driver see the
  746. I8K Linux utilities web site at:
  747. <http://people.debian.org/~dz/i8k/>
  748. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  749. Say N otherwise.
  750. config X86_REBOOTFIXUPS
  751. bool "Enable X86 board specific fixups for reboot"
  752. depends on X86_32
  753. ---help---
  754. This enables chipset and/or board specific fixups to be done
  755. in order to get reboot to work correctly. This is only needed on
  756. some combinations of hardware and BIOS. The symptom, for which
  757. this config is intended, is when reboot ends with a stalled/hung
  758. system.
  759. Currently, the only fixup is for the Geode machines using
  760. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  761. Say Y if you want to enable the fixup. Currently, it's safe to
  762. enable this option even if you don't need it.
  763. Say N otherwise.
  764. config MICROCODE
  765. tristate "/dev/cpu/microcode - microcode support"
  766. select FW_LOADER
  767. ---help---
  768. If you say Y here, you will be able to update the microcode on
  769. certain Intel and AMD processors. The Intel support is for the
  770. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  771. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  772. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  773. You will obviously need the actual microcode binary data itself
  774. which is not shipped with the Linux kernel.
  775. This option selects the general module only, you need to select
  776. at least one vendor specific module as well.
  777. To compile this driver as a module, choose M here: the
  778. module will be called microcode.
  779. config MICROCODE_INTEL
  780. bool "Intel microcode patch loading support"
  781. depends on MICROCODE
  782. default MICROCODE
  783. select FW_LOADER
  784. ---help---
  785. This options enables microcode patch loading support for Intel
  786. processors.
  787. For latest news and information on obtaining all the required
  788. Intel ingredients for this driver, check:
  789. <http://www.urbanmyth.org/microcode/>.
  790. config MICROCODE_AMD
  791. bool "AMD microcode patch loading support"
  792. depends on MICROCODE
  793. select FW_LOADER
  794. ---help---
  795. If you select this option, microcode patch loading support for AMD
  796. processors will be enabled.
  797. config MICROCODE_OLD_INTERFACE
  798. def_bool y
  799. depends on MICROCODE
  800. config X86_MSR
  801. tristate "/dev/cpu/*/msr - Model-specific register support"
  802. ---help---
  803. This device gives privileged processes access to the x86
  804. Model-Specific Registers (MSRs). It is a character device with
  805. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  806. MSR accesses are directed to a specific CPU on multi-processor
  807. systems.
  808. config X86_CPUID
  809. tristate "/dev/cpu/*/cpuid - CPU information support"
  810. ---help---
  811. This device gives processes access to the x86 CPUID instruction to
  812. be executed on a specific processor. It is a character device
  813. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  814. /dev/cpu/31/cpuid.
  815. config X86_CPU_DEBUG
  816. tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"
  817. ---help---
  818. If you select this option, this will provide various x86 CPUs
  819. information through debugfs.
  820. choice
  821. prompt "High Memory Support"
  822. default HIGHMEM4G if !X86_NUMAQ
  823. default HIGHMEM64G if X86_NUMAQ
  824. depends on X86_32
  825. config NOHIGHMEM
  826. bool "off"
  827. depends on !X86_NUMAQ
  828. ---help---
  829. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  830. However, the address space of 32-bit x86 processors is only 4
  831. Gigabytes large. That means that, if you have a large amount of
  832. physical memory, not all of it can be "permanently mapped" by the
  833. kernel. The physical memory that's not permanently mapped is called
  834. "high memory".
  835. If you are compiling a kernel which will never run on a machine with
  836. more than 1 Gigabyte total physical RAM, answer "off" here (default
  837. choice and suitable for most users). This will result in a "3GB/1GB"
  838. split: 3GB are mapped so that each process sees a 3GB virtual memory
  839. space and the remaining part of the 4GB virtual memory space is used
  840. by the kernel to permanently map as much physical memory as
  841. possible.
  842. If the machine has between 1 and 4 Gigabytes physical RAM, then
  843. answer "4GB" here.
  844. If more than 4 Gigabytes is used then answer "64GB" here. This
  845. selection turns Intel PAE (Physical Address Extension) mode on.
  846. PAE implements 3-level paging on IA32 processors. PAE is fully
  847. supported by Linux, PAE mode is implemented on all recent Intel
  848. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  849. then the kernel will not boot on CPUs that don't support PAE!
  850. The actual amount of total physical memory will either be
  851. auto detected or can be forced by using a kernel command line option
  852. such as "mem=256M". (Try "man bootparam" or see the documentation of
  853. your boot loader (lilo or loadlin) about how to pass options to the
  854. kernel at boot time.)
  855. If unsure, say "off".
  856. config HIGHMEM4G
  857. bool "4GB"
  858. depends on !X86_NUMAQ
  859. ---help---
  860. Select this if you have a 32-bit processor and between 1 and 4
  861. gigabytes of physical RAM.
  862. config HIGHMEM64G
  863. bool "64GB"
  864. depends on !M386 && !M486
  865. select X86_PAE
  866. ---help---
  867. Select this if you have a 32-bit processor and more than 4
  868. gigabytes of physical RAM.
  869. endchoice
  870. choice
  871. depends on EXPERIMENTAL
  872. prompt "Memory split" if EMBEDDED
  873. default VMSPLIT_3G
  874. depends on X86_32
  875. ---help---
  876. Select the desired split between kernel and user memory.
  877. If the address range available to the kernel is less than the
  878. physical memory installed, the remaining memory will be available
  879. as "high memory". Accessing high memory is a little more costly
  880. than low memory, as it needs to be mapped into the kernel first.
  881. Note that increasing the kernel address space limits the range
  882. available to user programs, making the address space there
  883. tighter. Selecting anything other than the default 3G/1G split
  884. will also likely make your kernel incompatible with binary-only
  885. kernel modules.
  886. If you are not absolutely sure what you are doing, leave this
  887. option alone!
  888. config VMSPLIT_3G
  889. bool "3G/1G user/kernel split"
  890. config VMSPLIT_3G_OPT
  891. depends on !X86_PAE
  892. bool "3G/1G user/kernel split (for full 1G low memory)"
  893. config VMSPLIT_2G
  894. bool "2G/2G user/kernel split"
  895. config VMSPLIT_2G_OPT
  896. depends on !X86_PAE
  897. bool "2G/2G user/kernel split (for full 2G low memory)"
  898. config VMSPLIT_1G
  899. bool "1G/3G user/kernel split"
  900. endchoice
  901. config PAGE_OFFSET
  902. hex
  903. default 0xB0000000 if VMSPLIT_3G_OPT
  904. default 0x80000000 if VMSPLIT_2G
  905. default 0x78000000 if VMSPLIT_2G_OPT
  906. default 0x40000000 if VMSPLIT_1G
  907. default 0xC0000000
  908. depends on X86_32
  909. config HIGHMEM
  910. def_bool y
  911. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  912. config X86_PAE
  913. bool "PAE (Physical Address Extension) Support"
  914. depends on X86_32 && !HIGHMEM4G
  915. ---help---
  916. PAE is required for NX support, and furthermore enables
  917. larger swapspace support for non-overcommit purposes. It
  918. has the cost of more pagetable lookup overhead, and also
  919. consumes more pagetable space per process.
  920. config ARCH_PHYS_ADDR_T_64BIT
  921. def_bool X86_64 || X86_PAE
  922. config DIRECT_GBPAGES
  923. bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
  924. default y
  925. depends on X86_64
  926. ---help---
  927. Allow the kernel linear mapping to use 1GB pages on CPUs that
  928. support it. This can improve the kernel's performance a tiny bit by
  929. reducing TLB pressure. If in doubt, say "Y".
  930. # Common NUMA Features
  931. config NUMA
  932. bool "Numa Memory Allocation and Scheduler Support"
  933. depends on SMP
  934. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  935. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  936. ---help---
  937. Enable NUMA (Non Uniform Memory Access) support.
  938. The kernel will try to allocate memory used by a CPU on the
  939. local memory controller of the CPU and add some more
  940. NUMA awareness to the kernel.
  941. For 64-bit this is recommended if the system is Intel Core i7
  942. (or later), AMD Opteron, or EM64T NUMA.
  943. For 32-bit this is only needed on (rare) 32-bit-only platforms
  944. that support NUMA topologies, such as NUMAQ / Summit, or if you
  945. boot a 32-bit kernel on a 64-bit NUMA platform.
  946. Otherwise, you should say N.
  947. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  948. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  949. config K8_NUMA
  950. def_bool y
  951. prompt "Old style AMD Opteron NUMA detection"
  952. depends on X86_64 && NUMA && PCI
  953. ---help---
  954. Enable K8 NUMA node topology detection. You should say Y here if
  955. you have a multi processor AMD K8 system. This uses an old
  956. method to read the NUMA configuration directly from the builtin
  957. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  958. instead, which also takes priority if both are compiled in.
  959. config X86_64_ACPI_NUMA
  960. def_bool y
  961. prompt "ACPI NUMA detection"
  962. depends on X86_64 && NUMA && ACPI && PCI
  963. select ACPI_NUMA
  964. ---help---
  965. Enable ACPI SRAT based node topology detection.
  966. # Some NUMA nodes have memory ranges that span
  967. # other nodes. Even though a pfn is valid and
  968. # between a node's start and end pfns, it may not
  969. # reside on that node. See memmap_init_zone()
  970. # for details.
  971. config NODES_SPAN_OTHER_NODES
  972. def_bool y
  973. depends on X86_64_ACPI_NUMA
  974. config NUMA_EMU
  975. bool "NUMA emulation"
  976. depends on X86_64 && NUMA
  977. ---help---
  978. Enable NUMA emulation. A flat machine will be split
  979. into virtual nodes when booted with "numa=fake=N", where N is the
  980. number of nodes. This is only useful for debugging.
  981. config NODES_SHIFT
  982. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  983. range 1 9
  984. default "9" if MAXSMP
  985. default "6" if X86_64
  986. default "4" if X86_NUMAQ
  987. default "3"
  988. depends on NEED_MULTIPLE_NODES
  989. ---help---
  990. Specify the maximum number of NUMA Nodes available on the target
  991. system. Increases memory reserved to accommodate various tables.
  992. config HAVE_ARCH_BOOTMEM
  993. def_bool y
  994. depends on X86_32 && NUMA
  995. config ARCH_HAVE_MEMORY_PRESENT
  996. def_bool y
  997. depends on X86_32 && DISCONTIGMEM
  998. config NEED_NODE_MEMMAP_SIZE
  999. def_bool y
  1000. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1001. config HAVE_ARCH_ALLOC_REMAP
  1002. def_bool y
  1003. depends on X86_32 && NUMA
  1004. config ARCH_FLATMEM_ENABLE
  1005. def_bool y
  1006. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
  1007. config ARCH_DISCONTIGMEM_ENABLE
  1008. def_bool y
  1009. depends on NUMA && X86_32
  1010. config ARCH_DISCONTIGMEM_DEFAULT
  1011. def_bool y
  1012. depends on NUMA && X86_32
  1013. config ARCH_PROC_KCORE_TEXT
  1014. def_bool y
  1015. depends on X86_64 && PROC_KCORE
  1016. config ARCH_SPARSEMEM_DEFAULT
  1017. def_bool y
  1018. depends on X86_64
  1019. config ARCH_SPARSEMEM_ENABLE
  1020. def_bool y
  1021. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1022. select SPARSEMEM_STATIC if X86_32
  1023. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1024. config ARCH_SELECT_MEMORY_MODEL
  1025. def_bool y
  1026. depends on ARCH_SPARSEMEM_ENABLE
  1027. config ARCH_MEMORY_PROBE
  1028. def_bool X86_64
  1029. depends on MEMORY_HOTPLUG
  1030. source "mm/Kconfig"
  1031. config HIGHPTE
  1032. bool "Allocate 3rd-level pagetables from highmem"
  1033. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  1034. ---help---
  1035. The VM uses one page table entry for each page of physical memory.
  1036. For systems with a lot of RAM, this can be wasteful of precious
  1037. low memory. Setting this option will put user-space page table
  1038. entries in high memory.
  1039. config X86_CHECK_BIOS_CORRUPTION
  1040. bool "Check for low memory corruption"
  1041. ---help---
  1042. Periodically check for memory corruption in low memory, which
  1043. is suspected to be caused by BIOS. Even when enabled in the
  1044. configuration, it is disabled at runtime. Enable it by
  1045. setting "memory_corruption_check=1" on the kernel command
  1046. line. By default it scans the low 64k of memory every 60
  1047. seconds; see the memory_corruption_check_size and
  1048. memory_corruption_check_period parameters in
  1049. Documentation/kernel-parameters.txt to adjust this.
  1050. When enabled with the default parameters, this option has
  1051. almost no overhead, as it reserves a relatively small amount
  1052. of memory and scans it infrequently. It both detects corruption
  1053. and prevents it from affecting the running system.
  1054. It is, however, intended as a diagnostic tool; if repeatable
  1055. BIOS-originated corruption always affects the same memory,
  1056. you can use memmap= to prevent the kernel from using that
  1057. memory.
  1058. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1059. bool "Set the default setting of memory_corruption_check"
  1060. depends on X86_CHECK_BIOS_CORRUPTION
  1061. default y
  1062. ---help---
  1063. Set whether the default state of memory_corruption_check is
  1064. on or off.
  1065. config X86_RESERVE_LOW_64K
  1066. bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
  1067. default y
  1068. ---help---
  1069. Reserve the first 64K of physical RAM on BIOSes that are known
  1070. to potentially corrupt that memory range. A numbers of BIOSes are
  1071. known to utilize this area during suspend/resume, so it must not
  1072. be used by the kernel.
  1073. Set this to N if you are absolutely sure that you trust the BIOS
  1074. to get all its memory reservations and usages right.
  1075. If you have doubts about the BIOS (e.g. suspend/resume does not
  1076. work or there's kernel crashes after certain hardware hotplug
  1077. events) and it's not AMI or Phoenix, then you might want to enable
  1078. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
  1079. corruption patterns.
  1080. Say Y if unsure.
  1081. config MATH_EMULATION
  1082. bool
  1083. prompt "Math emulation" if X86_32
  1084. ---help---
  1085. Linux can emulate a math coprocessor (used for floating point
  1086. operations) if you don't have one. 486DX and Pentium processors have
  1087. a math coprocessor built in, 486SX and 386 do not, unless you added
  1088. a 487DX or 387, respectively. (The messages during boot time can
  1089. give you some hints here ["man dmesg"].) Everyone needs either a
  1090. coprocessor or this emulation.
  1091. If you don't have a math coprocessor, you need to say Y here; if you
  1092. say Y here even though you have a coprocessor, the coprocessor will
  1093. be used nevertheless. (This behavior can be changed with the kernel
  1094. command line option "no387", which comes handy if your coprocessor
  1095. is broken. Try "man bootparam" or see the documentation of your boot
  1096. loader (lilo or loadlin) about how to pass options to the kernel at
  1097. boot time.) This means that it is a good idea to say Y here if you
  1098. intend to use this kernel on different machines.
  1099. More information about the internals of the Linux math coprocessor
  1100. emulation can be found in <file:arch/x86/math-emu/README>.
  1101. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1102. kernel, it won't hurt.
  1103. config MTRR
  1104. bool
  1105. default y
  1106. prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
  1107. ---help---
  1108. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1109. the Memory Type Range Registers (MTRRs) may be used to control
  1110. processor access to memory ranges. This is most useful if you have
  1111. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1112. allows bus write transfers to be combined into a larger transfer
  1113. before bursting over the PCI/AGP bus. This can increase performance
  1114. of image write operations 2.5 times or more. Saying Y here creates a
  1115. /proc/mtrr file which may be used to manipulate your processor's
  1116. MTRRs. Typically the X server should use this.
  1117. This code has a reasonably generic interface so that similar
  1118. control registers on other processors can be easily supported
  1119. as well:
  1120. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1121. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1122. these, the ARRs are used to emulate the MTRRs.
  1123. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1124. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1125. write-combining. All of these processors are supported by this code
  1126. and it makes sense to say Y here if you have one of them.
  1127. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1128. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1129. can lead to all sorts of problems, so it's good to say Y here.
  1130. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1131. just add about 9 KB to your kernel.
  1132. See <file:Documentation/x86/mtrr.txt> for more information.
  1133. config MTRR_SANITIZER
  1134. def_bool y
  1135. prompt "MTRR cleanup support"
  1136. depends on MTRR
  1137. ---help---
  1138. Convert MTRR layout from continuous to discrete, so X drivers can
  1139. add writeback entries.
  1140. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1141. The largest mtrr entry size for a continuous block can be set with
  1142. mtrr_chunk_size.
  1143. If unsure, say Y.
  1144. config MTRR_SANITIZER_ENABLE_DEFAULT
  1145. int "MTRR cleanup enable value (0-1)"
  1146. range 0 1
  1147. default "0"
  1148. depends on MTRR_SANITIZER
  1149. ---help---
  1150. Enable mtrr cleanup default value
  1151. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1152. int "MTRR cleanup spare reg num (0-7)"
  1153. range 0 7
  1154. default "1"
  1155. depends on MTRR_SANITIZER
  1156. ---help---
  1157. mtrr cleanup spare entries default, it can be changed via
  1158. mtrr_spare_reg_nr=N on the kernel command line.
  1159. config X86_PAT
  1160. bool
  1161. default y
  1162. prompt "x86 PAT support" if EMBEDDED
  1163. depends on MTRR
  1164. ---help---
  1165. Use PAT attributes to setup page level cache control.
  1166. PATs are the modern equivalents of MTRRs and are much more
  1167. flexible than MTRRs.
  1168. Say N here if you see bootup problems (boot crash, boot hang,
  1169. spontaneous reboots) or a non-working video driver.
  1170. If unsure, say Y.
  1171. config ARCH_USES_PG_UNCACHED
  1172. def_bool y
  1173. depends on X86_PAT
  1174. config EFI
  1175. bool "EFI runtime service support"
  1176. depends on ACPI
  1177. ---help---
  1178. This enables the kernel to use EFI runtime services that are
  1179. available (such as the EFI variable services).
  1180. This option is only useful on systems that have EFI firmware.
  1181. In addition, you should use the latest ELILO loader available
  1182. at <http://elilo.sourceforge.net> in order to take advantage
  1183. of EFI runtime services. However, even with this option, the
  1184. resultant kernel should continue to boot on existing non-EFI
  1185. platforms.
  1186. config SECCOMP
  1187. def_bool y
  1188. prompt "Enable seccomp to safely compute untrusted bytecode"
  1189. ---help---
  1190. This kernel feature is useful for number crunching applications
  1191. that may need to compute untrusted bytecode during their
  1192. execution. By using pipes or other transports made available to
  1193. the process as file descriptors supporting the read/write
  1194. syscalls, it's possible to isolate those applications in
  1195. their own address space using seccomp. Once seccomp is
  1196. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1197. and the task is only allowed to execute a few safe syscalls
  1198. defined by each seccomp mode.
  1199. If unsure, say Y. Only embedded should say N here.
  1200. config CC_STACKPROTECTOR
  1201. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1202. ---help---
  1203. This option turns on the -fstack-protector GCC feature. This
  1204. feature puts, at the beginning of functions, a canary value on
  1205. the stack just before the return address, and validates
  1206. the value just before actually returning. Stack based buffer
  1207. overflows (that need to overwrite this return address) now also
  1208. overwrite the canary, which gets detected and the attack is then
  1209. neutralized via a kernel panic.
  1210. This feature requires gcc version 4.2 or above, or a distribution
  1211. gcc with the feature backported. Older versions are automatically
  1212. detected and for those versions, this configuration option is
  1213. ignored. (and a warning is printed during bootup)
  1214. source kernel/Kconfig.hz
  1215. config KEXEC
  1216. bool "kexec system call"
  1217. ---help---
  1218. kexec is a system call that implements the ability to shutdown your
  1219. current kernel, and to start another kernel. It is like a reboot
  1220. but it is independent of the system firmware. And like a reboot
  1221. you can start any kernel with it, not just Linux.
  1222. The name comes from the similarity to the exec system call.
  1223. It is an ongoing process to be certain the hardware in a machine
  1224. is properly shutdown, so do not be surprised if this code does not
  1225. initially work for you. It may help to enable device hotplugging
  1226. support. As of this writing the exact hardware interface is
  1227. strongly in flux, so no good recommendation can be made.
  1228. config CRASH_DUMP
  1229. bool "kernel crash dumps"
  1230. depends on X86_64 || (X86_32 && HIGHMEM)
  1231. ---help---
  1232. Generate crash dump after being started by kexec.
  1233. This should be normally only set in special crash dump kernels
  1234. which are loaded in the main kernel with kexec-tools into
  1235. a specially reserved region and then later executed after
  1236. a crash by kdump/kexec. The crash dump kernel must be compiled
  1237. to a memory address not used by the main kernel or BIOS using
  1238. PHYSICAL_START, or it must be built as a relocatable image
  1239. (CONFIG_RELOCATABLE=y).
  1240. For more details see Documentation/kdump/kdump.txt
  1241. config KEXEC_JUMP
  1242. bool "kexec jump (EXPERIMENTAL)"
  1243. depends on EXPERIMENTAL
  1244. depends on KEXEC && HIBERNATION
  1245. ---help---
  1246. Jump between original kernel and kexeced kernel and invoke
  1247. code in physical address mode via KEXEC
  1248. config PHYSICAL_START
  1249. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1250. default "0x1000000"
  1251. ---help---
  1252. This gives the physical address where the kernel is loaded.
  1253. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1254. bzImage will decompress itself to above physical address and
  1255. run from there. Otherwise, bzImage will run from the address where
  1256. it has been loaded by the boot loader and will ignore above physical
  1257. address.
  1258. In normal kdump cases one does not have to set/change this option
  1259. as now bzImage can be compiled as a completely relocatable image
  1260. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1261. address. This option is mainly useful for the folks who don't want
  1262. to use a bzImage for capturing the crash dump and want to use a
  1263. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1264. to be specifically compiled to run from a specific memory area
  1265. (normally a reserved region) and this option comes handy.
  1266. So if you are using bzImage for capturing the crash dump,
  1267. leave the value here unchanged to 0x1000000 and set
  1268. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1269. for capturing the crash dump change this value to start of
  1270. the reserved region. In other words, it can be set based on
  1271. the "X" value as specified in the "crashkernel=YM@XM"
  1272. command line boot parameter passed to the panic-ed
  1273. kernel. Please take a look at Documentation/kdump/kdump.txt
  1274. for more details about crash dumps.
  1275. Usage of bzImage for capturing the crash dump is recommended as
  1276. one does not have to build two kernels. Same kernel can be used
  1277. as production kernel and capture kernel. Above option should have
  1278. gone away after relocatable bzImage support is introduced. But it
  1279. is present because there are users out there who continue to use
  1280. vmlinux for dump capture. This option should go away down the
  1281. line.
  1282. Don't change this unless you know what you are doing.
  1283. config RELOCATABLE
  1284. bool "Build a relocatable kernel"
  1285. default y
  1286. ---help---
  1287. This builds a kernel image that retains relocation information
  1288. so it can be loaded someplace besides the default 1MB.
  1289. The relocations tend to make the kernel binary about 10% larger,
  1290. but are discarded at runtime.
  1291. One use is for the kexec on panic case where the recovery kernel
  1292. must live at a different physical address than the primary
  1293. kernel.
  1294. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1295. it has been loaded at and the compile time physical address
  1296. (CONFIG_PHYSICAL_START) is ignored.
  1297. # Relocation on x86-32 needs some additional build support
  1298. config X86_NEED_RELOCS
  1299. def_bool y
  1300. depends on X86_32 && RELOCATABLE
  1301. config PHYSICAL_ALIGN
  1302. hex
  1303. prompt "Alignment value to which kernel should be aligned" if X86_32
  1304. default "0x1000000"
  1305. range 0x2000 0x1000000
  1306. ---help---
  1307. This value puts the alignment restrictions on physical address
  1308. where kernel is loaded and run from. Kernel is compiled for an
  1309. address which meets above alignment restriction.
  1310. If bootloader loads the kernel at a non-aligned address and
  1311. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1312. address aligned to above value and run from there.
  1313. If bootloader loads the kernel at a non-aligned address and
  1314. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1315. load address and decompress itself to the address it has been
  1316. compiled for and run from there. The address for which kernel is
  1317. compiled already meets above alignment restrictions. Hence the
  1318. end result is that kernel runs from a physical address meeting
  1319. above alignment restrictions.
  1320. Don't change this unless you know what you are doing.
  1321. config HOTPLUG_CPU
  1322. bool "Support for hot-pluggable CPUs"
  1323. depends on SMP && HOTPLUG
  1324. ---help---
  1325. Say Y here to allow turning CPUs off and on. CPUs can be
  1326. controlled through /sys/devices/system/cpu.
  1327. ( Note: power management support will enable this option
  1328. automatically on SMP systems. )
  1329. Say N if you want to disable CPU hotplug.
  1330. config COMPAT_VDSO
  1331. def_bool y
  1332. prompt "Compat VDSO support"
  1333. depends on X86_32 || IA32_EMULATION
  1334. ---help---
  1335. Map the 32-bit VDSO to the predictable old-style address too.
  1336. Say N here if you are running a sufficiently recent glibc
  1337. version (2.3.3 or later), to remove the high-mapped
  1338. VDSO mapping and to exclusively use the randomized VDSO.
  1339. If unsure, say Y.
  1340. config CMDLINE_BOOL
  1341. bool "Built-in kernel command line"
  1342. default n
  1343. ---help---
  1344. Allow for specifying boot arguments to the kernel at
  1345. build time. On some systems (e.g. embedded ones), it is
  1346. necessary or convenient to provide some or all of the
  1347. kernel boot arguments with the kernel itself (that is,
  1348. to not rely on the boot loader to provide them.)
  1349. To compile command line arguments into the kernel,
  1350. set this option to 'Y', then fill in the
  1351. the boot arguments in CONFIG_CMDLINE.
  1352. Systems with fully functional boot loaders (i.e. non-embedded)
  1353. should leave this option set to 'N'.
  1354. config CMDLINE
  1355. string "Built-in kernel command string"
  1356. depends on CMDLINE_BOOL
  1357. default ""
  1358. ---help---
  1359. Enter arguments here that should be compiled into the kernel
  1360. image and used at boot time. If the boot loader provides a
  1361. command line at boot time, it is appended to this string to
  1362. form the full kernel command line, when the system boots.
  1363. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1364. change this behavior.
  1365. In most cases, the command line (whether built-in or provided
  1366. by the boot loader) should specify the device for the root
  1367. file system.
  1368. config CMDLINE_OVERRIDE
  1369. bool "Built-in command line overrides boot loader arguments"
  1370. default n
  1371. depends on CMDLINE_BOOL
  1372. ---help---
  1373. Set this option to 'Y' to have the kernel ignore the boot loader
  1374. command line, and use ONLY the built-in command line.
  1375. This is used to work around broken boot loaders. This should
  1376. be set to 'N' under normal conditions.
  1377. endmenu
  1378. config ARCH_ENABLE_MEMORY_HOTPLUG
  1379. def_bool y
  1380. depends on X86_64 || (X86_32 && HIGHMEM)
  1381. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1382. def_bool y
  1383. depends on MEMORY_HOTPLUG
  1384. config HAVE_ARCH_EARLY_PFN_TO_NID
  1385. def_bool X86_64
  1386. depends on NUMA
  1387. menu "Power management and ACPI options"
  1388. config ARCH_HIBERNATION_HEADER
  1389. def_bool y
  1390. depends on X86_64 && HIBERNATION
  1391. source "kernel/power/Kconfig"
  1392. source "drivers/acpi/Kconfig"
  1393. source "drivers/sfi/Kconfig"
  1394. config X86_APM_BOOT
  1395. bool
  1396. default y
  1397. depends on APM || APM_MODULE
  1398. menuconfig APM
  1399. tristate "APM (Advanced Power Management) BIOS support"
  1400. depends on X86_32 && PM_SLEEP
  1401. ---help---
  1402. APM is a BIOS specification for saving power using several different
  1403. techniques. This is mostly useful for battery powered laptops with
  1404. APM compliant BIOSes. If you say Y here, the system time will be
  1405. reset after a RESUME operation, the /proc/apm device will provide
  1406. battery status information, and user-space programs will receive
  1407. notification of APM "events" (e.g. battery status change).
  1408. If you select "Y" here, you can disable actual use of the APM
  1409. BIOS by passing the "apm=off" option to the kernel at boot time.
  1410. Note that the APM support is almost completely disabled for
  1411. machines with more than one CPU.
  1412. In order to use APM, you will need supporting software. For location
  1413. and more information, read <file:Documentation/power/pm.txt> and the
  1414. Battery Powered Linux mini-HOWTO, available from
  1415. <http://www.tldp.org/docs.html#howto>.
  1416. This driver does not spin down disk drives (see the hdparm(8)
  1417. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1418. VESA-compliant "green" monitors.
  1419. This driver does not support the TI 4000M TravelMate and the ACER
  1420. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1421. desktop machines also don't have compliant BIOSes, and this driver
  1422. may cause those machines to panic during the boot phase.
  1423. Generally, if you don't have a battery in your machine, there isn't
  1424. much point in using this driver and you should say N. If you get
  1425. random kernel OOPSes or reboots that don't seem to be related to
  1426. anything, try disabling/enabling this option (or disabling/enabling
  1427. APM in your BIOS).
  1428. Some other things you should try when experiencing seemingly random,
  1429. "weird" problems:
  1430. 1) make sure that you have enough swap space and that it is
  1431. enabled.
  1432. 2) pass the "no-hlt" option to the kernel
  1433. 3) switch on floating point emulation in the kernel and pass
  1434. the "no387" option to the kernel
  1435. 4) pass the "floppy=nodma" option to the kernel
  1436. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1437. all but the first 4 MB of RAM)
  1438. 6) make sure that the CPU is not over clocked.
  1439. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1440. 8) disable the cache from your BIOS settings
  1441. 9) install a fan for the video card or exchange video RAM
  1442. 10) install a better fan for the CPU
  1443. 11) exchange RAM chips
  1444. 12) exchange the motherboard.
  1445. To compile this driver as a module, choose M here: the
  1446. module will be called apm.
  1447. if APM
  1448. config APM_IGNORE_USER_SUSPEND
  1449. bool "Ignore USER SUSPEND"
  1450. ---help---
  1451. This option will ignore USER SUSPEND requests. On machines with a
  1452. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1453. series notebooks, it is necessary to say Y because of a BIOS bug.
  1454. config APM_DO_ENABLE
  1455. bool "Enable PM at boot time"
  1456. ---help---
  1457. Enable APM features at boot time. From page 36 of the APM BIOS
  1458. specification: "When disabled, the APM BIOS does not automatically
  1459. power manage devices, enter the Standby State, enter the Suspend
  1460. State, or take power saving steps in response to CPU Idle calls."
  1461. This driver will make CPU Idle calls when Linux is idle (unless this
  1462. feature is turned off -- see "Do CPU IDLE calls", below). This
  1463. should always save battery power, but more complicated APM features
  1464. will be dependent on your BIOS implementation. You may need to turn
  1465. this option off if your computer hangs at boot time when using APM
  1466. support, or if it beeps continuously instead of suspending. Turn
  1467. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1468. T400CDT. This is off by default since most machines do fine without
  1469. this feature.
  1470. config APM_CPU_IDLE
  1471. bool "Make CPU Idle calls when idle"
  1472. ---help---
  1473. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1474. On some machines, this can activate improved power savings, such as
  1475. a slowed CPU clock rate, when the machine is idle. These idle calls
  1476. are made after the idle loop has run for some length of time (e.g.,
  1477. 333 mS). On some machines, this will cause a hang at boot time or
  1478. whenever the CPU becomes idle. (On machines with more than one CPU,
  1479. this option does nothing.)
  1480. config APM_DISPLAY_BLANK
  1481. bool "Enable console blanking using APM"
  1482. ---help---
  1483. Enable console blanking using the APM. Some laptops can use this to
  1484. turn off the LCD backlight when the screen blanker of the Linux
  1485. virtual console blanks the screen. Note that this is only used by
  1486. the virtual console screen blanker, and won't turn off the backlight
  1487. when using the X Window system. This also doesn't have anything to
  1488. do with your VESA-compliant power-saving monitor. Further, this
  1489. option doesn't work for all laptops -- it might not turn off your
  1490. backlight at all, or it might print a lot of errors to the console,
  1491. especially if you are using gpm.
  1492. config APM_ALLOW_INTS
  1493. bool "Allow interrupts during APM BIOS calls"
  1494. ---help---
  1495. Normally we disable external interrupts while we are making calls to
  1496. the APM BIOS as a measure to lessen the effects of a badly behaving
  1497. BIOS implementation. The BIOS should reenable interrupts if it
  1498. needs to. Unfortunately, some BIOSes do not -- especially those in
  1499. many of the newer IBM Thinkpads. If you experience hangs when you
  1500. suspend, try setting this to Y. Otherwise, say N.
  1501. endif # APM
  1502. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1503. source "drivers/cpuidle/Kconfig"
  1504. source "drivers/idle/Kconfig"
  1505. endmenu
  1506. menu "Bus options (PCI etc.)"
  1507. config PCI
  1508. bool "PCI support"
  1509. default y
  1510. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1511. ---help---
  1512. Find out whether you have a PCI motherboard. PCI is the name of a
  1513. bus system, i.e. the way the CPU talks to the other stuff inside
  1514. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1515. VESA. If you have PCI, say Y, otherwise N.
  1516. choice
  1517. prompt "PCI access mode"
  1518. depends on X86_32 && PCI
  1519. default PCI_GOANY
  1520. ---help---
  1521. On PCI systems, the BIOS can be used to detect the PCI devices and
  1522. determine their configuration. However, some old PCI motherboards
  1523. have BIOS bugs and may crash if this is done. Also, some embedded
  1524. PCI-based systems don't have any BIOS at all. Linux can also try to
  1525. detect the PCI hardware directly without using the BIOS.
  1526. With this option, you can specify how Linux should detect the
  1527. PCI devices. If you choose "BIOS", the BIOS will be used,
  1528. if you choose "Direct", the BIOS won't be used, and if you
  1529. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1530. If you choose "Any", the kernel will try MMCONFIG, then the
  1531. direct access method and falls back to the BIOS if that doesn't
  1532. work. If unsure, go with the default, which is "Any".
  1533. config PCI_GOBIOS
  1534. bool "BIOS"
  1535. config PCI_GOMMCONFIG
  1536. bool "MMConfig"
  1537. config PCI_GODIRECT
  1538. bool "Direct"
  1539. config PCI_GOOLPC
  1540. bool "OLPC"
  1541. depends on OLPC
  1542. config PCI_GOANY
  1543. bool "Any"
  1544. endchoice
  1545. config PCI_BIOS
  1546. def_bool y
  1547. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1548. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1549. config PCI_DIRECT
  1550. def_bool y
  1551. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1552. config PCI_MMCONFIG
  1553. def_bool y
  1554. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1555. config PCI_OLPC
  1556. def_bool y
  1557. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1558. config PCI_DOMAINS
  1559. def_bool y
  1560. depends on PCI
  1561. config PCI_MMCONFIG
  1562. bool "Support mmconfig PCI config space access"
  1563. depends on X86_64 && PCI && ACPI
  1564. config DMAR
  1565. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1566. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1567. help
  1568. DMA remapping (DMAR) devices support enables independent address
  1569. translations for Direct Memory Access (DMA) from devices.
  1570. These DMA remapping devices are reported via ACPI tables
  1571. and include PCI device scope covered by these DMA
  1572. remapping devices.
  1573. config DMAR_DEFAULT_ON
  1574. def_bool y
  1575. prompt "Enable DMA Remapping Devices by default"
  1576. depends on DMAR
  1577. help
  1578. Selecting this option will enable a DMAR device at boot time if
  1579. one is found. If this option is not selected, DMAR support can
  1580. be enabled by passing intel_iommu=on to the kernel. It is
  1581. recommended you say N here while the DMAR code remains
  1582. experimental.
  1583. config DMAR_BROKEN_GFX_WA
  1584. def_bool n
  1585. prompt "Workaround broken graphics drivers (going away soon)"
  1586. depends on DMAR && BROKEN
  1587. ---help---
  1588. Current Graphics drivers tend to use physical address
  1589. for DMA and avoid using DMA APIs. Setting this config
  1590. option permits the IOMMU driver to set a unity map for
  1591. all the OS-visible memory. Hence the driver can continue
  1592. to use physical addresses for DMA, at least until this
  1593. option is removed in the 2.6.32 kernel.
  1594. config DMAR_FLOPPY_WA
  1595. def_bool y
  1596. depends on DMAR
  1597. ---help---
  1598. Floppy disk drivers are known to bypass DMA API calls
  1599. thereby failing to work when IOMMU is enabled. This
  1600. workaround will setup a 1:1 mapping for the first
  1601. 16MiB to make floppy (an ISA device) work.
  1602. config INTR_REMAP
  1603. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1604. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1605. ---help---
  1606. Supports Interrupt remapping for IO-APIC and MSI devices.
  1607. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1608. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1609. source "drivers/pci/pcie/Kconfig"
  1610. source "drivers/pci/Kconfig"
  1611. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1612. config ISA_DMA_API
  1613. def_bool y
  1614. if X86_32
  1615. config ISA
  1616. bool "ISA support"
  1617. ---help---
  1618. Find out whether you have ISA slots on your motherboard. ISA is the
  1619. name of a bus system, i.e. the way the CPU talks to the other stuff
  1620. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1621. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1622. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1623. config EISA
  1624. bool "EISA support"
  1625. depends on ISA
  1626. ---help---
  1627. The Extended Industry Standard Architecture (EISA) bus was
  1628. developed as an open alternative to the IBM MicroChannel bus.
  1629. The EISA bus provided some of the features of the IBM MicroChannel
  1630. bus while maintaining backward compatibility with cards made for
  1631. the older ISA bus. The EISA bus saw limited use between 1988 and
  1632. 1995 when it was made obsolete by the PCI bus.
  1633. Say Y here if you are building a kernel for an EISA-based machine.
  1634. Otherwise, say N.
  1635. source "drivers/eisa/Kconfig"
  1636. config MCA
  1637. bool "MCA support"
  1638. ---help---
  1639. MicroChannel Architecture is found in some IBM PS/2 machines and
  1640. laptops. It is a bus system similar to PCI or ISA. See
  1641. <file:Documentation/mca.txt> (and especially the web page given
  1642. there) before attempting to build an MCA bus kernel.
  1643. source "drivers/mca/Kconfig"
  1644. config SCx200
  1645. tristate "NatSemi SCx200 support"
  1646. ---help---
  1647. This provides basic support for National Semiconductor's
  1648. (now AMD's) Geode processors. The driver probes for the
  1649. PCI-IDs of several on-chip devices, so its a good dependency
  1650. for other scx200_* drivers.
  1651. If compiled as a module, the driver is named scx200.
  1652. config SCx200HR_TIMER
  1653. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1654. depends on SCx200 && GENERIC_TIME
  1655. default y
  1656. ---help---
  1657. This driver provides a clocksource built upon the on-chip
  1658. 27MHz high-resolution timer. Its also a workaround for
  1659. NSC Geode SC-1100's buggy TSC, which loses time when the
  1660. processor goes idle (as is done by the scheduler). The
  1661. other workaround is idle=poll boot option.
  1662. config GEODE_MFGPT_TIMER
  1663. def_bool y
  1664. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1665. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1666. ---help---
  1667. This driver provides a clock event source based on the MFGPT
  1668. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1669. MFGPTs have a better resolution and max interval than the
  1670. generic PIT, and are suitable for use as high-res timers.
  1671. config OLPC
  1672. bool "One Laptop Per Child support"
  1673. default n
  1674. ---help---
  1675. Add support for detecting the unique features of the OLPC
  1676. XO hardware.
  1677. endif # X86_32
  1678. config K8_NB
  1679. def_bool y
  1680. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1681. source "drivers/pcmcia/Kconfig"
  1682. source "drivers/pci/hotplug/Kconfig"
  1683. endmenu
  1684. menu "Executable file formats / Emulations"
  1685. source "fs/Kconfig.binfmt"
  1686. config IA32_EMULATION
  1687. bool "IA32 Emulation"
  1688. depends on X86_64
  1689. select COMPAT_BINFMT_ELF
  1690. ---help---
  1691. Include code to run 32-bit programs under a 64-bit kernel. You should
  1692. likely turn this on, unless you're 100% sure that you don't have any
  1693. 32-bit programs left.
  1694. config IA32_AOUT
  1695. tristate "IA32 a.out support"
  1696. depends on IA32_EMULATION
  1697. ---help---
  1698. Support old a.out binaries in the 32bit emulation.
  1699. config COMPAT
  1700. def_bool y
  1701. depends on IA32_EMULATION
  1702. config COMPAT_FOR_U64_ALIGNMENT
  1703. def_bool COMPAT
  1704. depends on X86_64
  1705. config SYSVIPC_COMPAT
  1706. def_bool y
  1707. depends on COMPAT && SYSVIPC
  1708. endmenu
  1709. config HAVE_ATOMIC_IOMAP
  1710. def_bool y
  1711. depends on X86_32
  1712. source "net/Kconfig"
  1713. source "drivers/Kconfig"
  1714. source "drivers/firmware/Kconfig"
  1715. source "fs/Kconfig"
  1716. source "arch/x86/Kconfig.debug"
  1717. source "security/Kconfig"
  1718. source "crypto/Kconfig"
  1719. source "arch/x86/kvm/Kconfig"
  1720. source "lib/Kconfig"