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