Kconfig 54 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_IDE
  18. select HAVE_OPROFILE
  19. select HAVE_KPROBES
  20. select HAVE_KRETPROBES
  21. select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
  22. select HAVE_ARCH_KGDB if !X86_VOYAGER
  23. config GENERIC_LOCKBREAK
  24. def_bool n
  25. config GENERIC_TIME
  26. def_bool y
  27. config GENERIC_CMOS_UPDATE
  28. def_bool y
  29. config CLOCKSOURCE_WATCHDOG
  30. def_bool y
  31. config GENERIC_CLOCKEVENTS
  32. def_bool y
  33. config GENERIC_CLOCKEVENTS_BROADCAST
  34. def_bool y
  35. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  36. config LOCKDEP_SUPPORT
  37. def_bool y
  38. config STACKTRACE_SUPPORT
  39. def_bool y
  40. config HAVE_LATENCYTOP_SUPPORT
  41. def_bool y
  42. config FAST_CMPXCHG_LOCAL
  43. bool
  44. default y
  45. config MMU
  46. def_bool y
  47. config ZONE_DMA
  48. def_bool y
  49. config SBUS
  50. bool
  51. config GENERIC_ISA_DMA
  52. def_bool y
  53. config GENERIC_IOMAP
  54. def_bool y
  55. config GENERIC_BUG
  56. def_bool y
  57. depends on BUG
  58. config GENERIC_FIND_FIRST_BIT
  59. def_bool y
  60. config GENERIC_FIND_NEXT_BIT
  61. def_bool y
  62. config GENERIC_HWEIGHT
  63. def_bool y
  64. config GENERIC_GPIO
  65. def_bool n
  66. config ARCH_MAY_HAVE_PC_FDC
  67. def_bool y
  68. config DMI
  69. def_bool y
  70. config RWSEM_GENERIC_SPINLOCK
  71. def_bool !X86_XADD
  72. config RWSEM_XCHGADD_ALGORITHM
  73. def_bool X86_XADD
  74. config ARCH_HAS_ILOG2_U32
  75. def_bool n
  76. config ARCH_HAS_ILOG2_U64
  77. def_bool n
  78. config ARCH_HAS_CPU_IDLE_WAIT
  79. def_bool y
  80. config GENERIC_CALIBRATE_DELAY
  81. def_bool y
  82. config GENERIC_TIME_VSYSCALL
  83. bool
  84. default X86_64
  85. config ARCH_HAS_CPU_RELAX
  86. def_bool y
  87. config HAVE_SETUP_PER_CPU_AREA
  88. def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
  89. config HAVE_CPUMASK_OF_CPU_MAP
  90. def_bool X86_64_SMP
  91. config ARCH_HIBERNATION_POSSIBLE
  92. def_bool y
  93. depends on !SMP || !X86_VOYAGER
  94. config ARCH_SUSPEND_POSSIBLE
  95. def_bool y
  96. depends on !X86_VOYAGER
  97. config ZONE_DMA32
  98. bool
  99. default X86_64
  100. config ARCH_POPULATES_NODE_MAP
  101. def_bool y
  102. config AUDIT_ARCH
  103. bool
  104. default X86_64
  105. config ARCH_SUPPORTS_AOUT
  106. def_bool y
  107. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  108. def_bool y
  109. # Use the generic interrupt handling code in kernel/irq/:
  110. config GENERIC_HARDIRQS
  111. bool
  112. default y
  113. config GENERIC_IRQ_PROBE
  114. bool
  115. default y
  116. config GENERIC_PENDING_IRQ
  117. bool
  118. depends on GENERIC_HARDIRQS && SMP
  119. default y
  120. config X86_SMP
  121. bool
  122. depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
  123. default y
  124. config X86_32_SMP
  125. def_bool y
  126. depends on X86_32 && SMP
  127. config X86_64_SMP
  128. def_bool y
  129. depends on X86_64 && SMP
  130. config X86_HT
  131. bool
  132. depends on SMP
  133. depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
  134. default y
  135. config X86_BIOS_REBOOT
  136. bool
  137. depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
  138. default y
  139. config X86_TRAMPOLINE
  140. bool
  141. depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
  142. default y
  143. config KTIME_SCALAR
  144. def_bool X86_32
  145. source "init/Kconfig"
  146. menu "Processor type and features"
  147. source "kernel/time/Kconfig"
  148. config SMP
  149. bool "Symmetric multi-processing support"
  150. ---help---
  151. This enables support for systems with more than one CPU. If you have
  152. a system with only one CPU, like most personal computers, say N. If
  153. you have a system with more than one CPU, say Y.
  154. If you say N here, the kernel will run on single and multiprocessor
  155. machines, but will use only one CPU of a multiprocessor machine. If
  156. you say Y here, the kernel will run on many, but not all,
  157. singleprocessor machines. On a singleprocessor machine, the kernel
  158. will run faster if you say N here.
  159. Note that if you say Y here and choose architecture "586" or
  160. "Pentium" under "Processor family", the kernel will not work on 486
  161. architectures. Similarly, multiprocessor kernels for the "PPro"
  162. architecture may not work on all Pentium based boards.
  163. People using multiprocessor machines who say Y here should also say
  164. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  165. Management" code will be disabled if you say Y here.
  166. See also <file:Documentation/i386/IO-APIC.txt>,
  167. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  168. <http://www.tldp.org/docs.html#howto>.
  169. If you don't know what to do here, say N.
  170. choice
  171. prompt "Subarchitecture Type"
  172. default X86_PC
  173. config X86_PC
  174. bool "PC-compatible"
  175. help
  176. Choose this option if your computer is a standard PC or compatible.
  177. config X86_ELAN
  178. bool "AMD Elan"
  179. depends on X86_32
  180. help
  181. Select this for an AMD Elan processor.
  182. Do not use this option for K6/Athlon/Opteron processors!
  183. If unsure, choose "PC-compatible" instead.
  184. config X86_VOYAGER
  185. bool "Voyager (NCR)"
  186. depends on X86_32 && (SMP || BROKEN)
  187. help
  188. Voyager is an MCA-based 32-way capable SMP architecture proprietary
  189. to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
  190. *** WARNING ***
  191. If you do not specifically know you have a Voyager based machine,
  192. say N here, otherwise the kernel you build will not be bootable.
  193. config X86_NUMAQ
  194. bool "NUMAQ (IBM/Sequent)"
  195. depends on SMP && X86_32
  196. select NUMA
  197. help
  198. This option is used for getting Linux to run on a (IBM/Sequent) NUMA
  199. multiquad box. This changes the way that processors are bootstrapped,
  200. and uses Clustered Logical APIC addressing mode instead of Flat Logical.
  201. You will need a new lynxer.elf file to flash your firmware with - send
  202. email to <Martin.Bligh@us.ibm.com>.
  203. config X86_SUMMIT
  204. bool "Summit/EXA (IBM x440)"
  205. depends on X86_32 && SMP
  206. help
  207. This option is needed for IBM systems that use the Summit/EXA chipset.
  208. In particular, it is needed for the x440.
  209. If you don't have one of these computers, you should say N here.
  210. If you want to build a NUMA kernel, you must select ACPI.
  211. config X86_BIGSMP
  212. bool "Support for other sub-arch SMP systems with more than 8 CPUs"
  213. depends on X86_32 && SMP
  214. help
  215. This option is needed for the systems that have more than 8 CPUs
  216. and if the system is not of any sub-arch type above.
  217. If you don't have such a system, you should say N here.
  218. config X86_VISWS
  219. bool "SGI 320/540 (Visual Workstation)"
  220. depends on X86_32
  221. help
  222. The SGI Visual Workstation series is an IA32-based workstation
  223. based on SGI systems chips with some legacy PC hardware attached.
  224. Say Y here to create a kernel to run on the SGI 320 or 540.
  225. A kernel compiled for the Visual Workstation will not run on PCs
  226. and vice versa. See <file:Documentation/sgi-visws.txt> for details.
  227. config X86_GENERICARCH
  228. bool "Generic architecture (Summit, bigsmp, ES7000, default)"
  229. depends on X86_32
  230. help
  231. This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
  232. It is intended for a generic binary kernel.
  233. If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
  234. config X86_ES7000
  235. bool "Support for Unisys ES7000 IA32 series"
  236. depends on X86_32 && SMP
  237. help
  238. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  239. supposed to run on an IA32-based Unisys ES7000 system.
  240. Only choose this option if you have such a system, otherwise you
  241. should say N here.
  242. config X86_RDC321X
  243. bool "RDC R-321x SoC"
  244. depends on X86_32
  245. select M486
  246. select X86_REBOOTFIXUPS
  247. select GENERIC_GPIO
  248. select LEDS_CLASS
  249. select LEDS_GPIO
  250. help
  251. This option is needed for RDC R-321x system-on-chip, also known
  252. as R-8610-(G).
  253. If you don't have one of these chips, you should say N here.
  254. config X86_VSMP
  255. bool "Support for ScaleMP vSMP"
  256. select PARAVIRT
  257. depends on X86_64
  258. help
  259. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  260. supposed to run on these EM64T-based machines. Only choose this option
  261. if you have one of these machines.
  262. endchoice
  263. config SCHED_NO_NO_OMIT_FRAME_POINTER
  264. def_bool y
  265. prompt "Single-depth WCHAN output"
  266. depends on X86_32
  267. help
  268. Calculate simpler /proc/<PID>/wchan values. If this option
  269. is disabled then wchan values will recurse back to the
  270. caller function. This provides more accurate wchan values,
  271. at the expense of slightly more scheduling overhead.
  272. If in doubt, say "Y".
  273. menuconfig PARAVIRT_GUEST
  274. bool "Paravirtualized guest support"
  275. help
  276. Say Y here to get to see options related to running Linux under
  277. various hypervisors. This option alone does not add any kernel code.
  278. If you say N, all options in this submenu will be skipped and disabled.
  279. if PARAVIRT_GUEST
  280. source "arch/x86/xen/Kconfig"
  281. config VMI
  282. bool "VMI Guest support"
  283. select PARAVIRT
  284. depends on X86_32
  285. depends on !(X86_VISWS || X86_VOYAGER)
  286. help
  287. VMI provides a paravirtualized interface to the VMware ESX server
  288. (it could be used by other hypervisors in theory too, but is not
  289. at the moment), by linking the kernel to a GPL-ed ROM module
  290. provided by the hypervisor.
  291. source "arch/x86/lguest/Kconfig"
  292. config PARAVIRT
  293. bool "Enable paravirtualization code"
  294. depends on !(X86_VISWS || X86_VOYAGER)
  295. help
  296. This changes the kernel so it can modify itself when it is run
  297. under a hypervisor, potentially improving performance significantly
  298. over full virtualization. However, when run without a hypervisor
  299. the kernel is theoretically slower and slightly larger.
  300. endif
  301. config MEMTEST_BOOTPARAM
  302. bool "Memtest boot parameter"
  303. depends on X86_64
  304. default y
  305. help
  306. This option adds a kernel parameter 'memtest', which allows memtest
  307. to be disabled at boot. If this option is selected, memtest
  308. functionality can be disabled with memtest=0 on the kernel
  309. command line. The purpose of this option is to allow a single
  310. kernel image to be distributed with memtest built in, but not
  311. necessarily enabled.
  312. If you are unsure how to answer this question, answer Y.
  313. config MEMTEST_BOOTPARAM_VALUE
  314. int "Memtest boot parameter default value (0-4)"
  315. depends on MEMTEST_BOOTPARAM
  316. range 0 4
  317. default 0
  318. help
  319. This option sets the default value for the kernel parameter
  320. 'memtest', which allows memtest to be disabled at boot. If this
  321. option is set to 0 (zero), the memtest kernel parameter will
  322. default to 0, disabling memtest at bootup. If this option is
  323. set to 4, the memtest kernel parameter will default to 4,
  324. enabling memtest at bootup, and use that as pattern number.
  325. If you are unsure how to answer this question, answer 0.
  326. config ACPI_SRAT
  327. def_bool y
  328. depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
  329. select ACPI_NUMA
  330. config HAVE_ARCH_PARSE_SRAT
  331. def_bool y
  332. depends on ACPI_SRAT
  333. config X86_SUMMIT_NUMA
  334. def_bool y
  335. depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
  336. config X86_CYCLONE_TIMER
  337. def_bool y
  338. depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
  339. config ES7000_CLUSTERED_APIC
  340. def_bool y
  341. depends on SMP && X86_ES7000 && MPENTIUMIII
  342. source "arch/x86/Kconfig.cpu"
  343. config HPET_TIMER
  344. def_bool X86_64
  345. prompt "HPET Timer Support" if X86_32
  346. help
  347. Use the IA-PC HPET (High Precision Event Timer) to manage
  348. time in preference to the PIT and RTC, if a HPET is
  349. present.
  350. HPET is the next generation timer replacing legacy 8254s.
  351. The HPET provides a stable time base on SMP
  352. systems, unlike the TSC, but it is more expensive to access,
  353. as it is off-chip. You can find the HPET spec at
  354. <http://www.intel.com/hardwaredesign/hpetspec.htm>.
  355. You can safely choose Y here. However, HPET will only be
  356. activated if the platform and the BIOS support this feature.
  357. Otherwise the 8254 will be used for timing services.
  358. Choose N to continue using the legacy 8254 timer.
  359. config HPET_EMULATE_RTC
  360. def_bool y
  361. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  362. # Mark as embedded because too many people got it wrong.
  363. # The code disables itself when not needed.
  364. config GART_IOMMU
  365. bool "GART IOMMU support" if EMBEDDED
  366. default y
  367. select SWIOTLB
  368. select AGP
  369. depends on X86_64 && PCI
  370. help
  371. Support for full DMA access of devices with 32bit memory access only
  372. on systems with more than 3GB. This is usually needed for USB,
  373. sound, many IDE/SATA chipsets and some other devices.
  374. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  375. based hardware IOMMU and a software bounce buffer based IOMMU used
  376. on Intel systems and as fallback.
  377. The code is only active when needed (enough memory and limited
  378. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  379. too.
  380. config CALGARY_IOMMU
  381. bool "IBM Calgary IOMMU support"
  382. select SWIOTLB
  383. depends on X86_64 && PCI && EXPERIMENTAL
  384. help
  385. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  386. systems. Needed to run systems with more than 3GB of memory
  387. properly with 32-bit PCI devices that do not support DAC
  388. (Double Address Cycle). Calgary also supports bus level
  389. isolation, where all DMAs pass through the IOMMU. This
  390. prevents them from going anywhere except their intended
  391. destination. This catches hard-to-find kernel bugs and
  392. mis-behaving drivers and devices that do not use the DMA-API
  393. properly to set up their DMA buffers. The IOMMU can be
  394. turned off at boot time with the iommu=off parameter.
  395. Normally the kernel will make the right choice by itself.
  396. If unsure, say Y.
  397. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  398. def_bool y
  399. prompt "Should Calgary be enabled by default?"
  400. depends on CALGARY_IOMMU
  401. help
  402. Should Calgary be enabled by default? if you choose 'y', Calgary
  403. will be used (if it exists). If you choose 'n', Calgary will not be
  404. used even if it exists. If you choose 'n' and would like to use
  405. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  406. If unsure, say Y.
  407. config IOMMU_HELPER
  408. def_bool (CALGARY_IOMMU || GART_IOMMU)
  409. # need this always selected by IOMMU for the VIA workaround
  410. config SWIOTLB
  411. bool
  412. help
  413. Support for software bounce buffers used on x86-64 systems
  414. which don't have a hardware IOMMU (e.g. the current generation
  415. of Intel's x86-64 CPUs). Using this PCI devices which can only
  416. access 32-bits of memory can be used on systems with more than
  417. 3 GB of memory. If unsure, say Y.
  418. config NR_CPUS
  419. int "Maximum number of CPUs (2-255)"
  420. range 2 255
  421. depends on SMP
  422. default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
  423. default "8"
  424. help
  425. This allows you to specify the maximum number of CPUs which this
  426. kernel will support. The maximum supported value is 255 and the
  427. minimum value which makes sense is 2.
  428. This is purely to save memory - each supported CPU adds
  429. approximately eight kilobytes to the kernel image.
  430. config SCHED_SMT
  431. bool "SMT (Hyperthreading) scheduler support"
  432. depends on X86_HT
  433. help
  434. SMT scheduler support improves the CPU scheduler's decision making
  435. when dealing with Intel Pentium 4 chips with HyperThreading at a
  436. cost of slightly increased overhead in some places. If unsure say
  437. N here.
  438. config SCHED_MC
  439. def_bool y
  440. prompt "Multi-core scheduler support"
  441. depends on X86_HT
  442. help
  443. Multi-core scheduler support improves the CPU scheduler's decision
  444. making when dealing with multi-core CPU chips at a cost of slightly
  445. increased overhead in some places. If unsure say N here.
  446. source "kernel/Kconfig.preempt"
  447. config X86_UP_APIC
  448. bool "Local APIC support on uniprocessors"
  449. depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
  450. help
  451. A local APIC (Advanced Programmable Interrupt Controller) is an
  452. integrated interrupt controller in the CPU. If you have a single-CPU
  453. system which has a processor with a local APIC, you can say Y here to
  454. enable and use it. If you say Y here even though your machine doesn't
  455. have a local APIC, then the kernel will still run with no slowdown at
  456. all. The local APIC supports CPU-generated self-interrupts (timer,
  457. performance counters), and the NMI watchdog which detects hard
  458. lockups.
  459. config X86_UP_IOAPIC
  460. bool "IO-APIC support on uniprocessors"
  461. depends on X86_UP_APIC
  462. help
  463. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  464. SMP-capable replacement for PC-style interrupt controllers. Most
  465. SMP systems and many recent uniprocessor systems have one.
  466. If you have a single-CPU system with an IO-APIC, you can say Y here
  467. to use it. If you say Y here even though your machine doesn't have
  468. an IO-APIC, then the kernel will still run with no slowdown at all.
  469. config X86_LOCAL_APIC
  470. def_bool y
  471. depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
  472. config X86_IO_APIC
  473. def_bool y
  474. depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
  475. config X86_VISWS_APIC
  476. def_bool y
  477. depends on X86_32 && X86_VISWS
  478. config X86_MCE
  479. bool "Machine Check Exception"
  480. depends on !X86_VOYAGER
  481. ---help---
  482. Machine Check Exception support allows the processor to notify the
  483. kernel if it detects a problem (e.g. overheating, component failure).
  484. The action the kernel takes depends on the severity of the problem,
  485. ranging from a warning message on the console, to halting the machine.
  486. Your processor must be a Pentium or newer to support this - check the
  487. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  488. have a design flaw which leads to false MCE events - hence MCE is
  489. disabled on all P5 processors, unless explicitly enabled with "mce"
  490. as a boot argument. Similarly, if MCE is built in and creates a
  491. problem on some new non-standard machine, you can boot with "nomce"
  492. to disable it. MCE support simply ignores non-MCE processors like
  493. the 386 and 486, so nearly everyone can say Y here.
  494. config X86_MCE_INTEL
  495. def_bool y
  496. prompt "Intel MCE features"
  497. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  498. help
  499. Additional support for intel specific MCE features such as
  500. the thermal monitor.
  501. config X86_MCE_AMD
  502. def_bool y
  503. prompt "AMD MCE features"
  504. depends on X86_64 && X86_MCE && X86_LOCAL_APIC
  505. help
  506. Additional support for AMD specific MCE features such as
  507. the DRAM Error Threshold.
  508. config X86_MCE_NONFATAL
  509. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  510. depends on X86_32 && X86_MCE
  511. help
  512. Enabling this feature starts a timer that triggers every 5 seconds which
  513. will look at the machine check registers to see if anything happened.
  514. Non-fatal problems automatically get corrected (but still logged).
  515. Disable this if you don't want to see these messages.
  516. Seeing the messages this option prints out may be indicative of dying
  517. or out-of-spec (ie, overclocked) hardware.
  518. This option only does something on certain CPUs.
  519. (AMD Athlon/Duron and Intel Pentium 4)
  520. config X86_MCE_P4THERMAL
  521. bool "check for P4 thermal throttling interrupt."
  522. depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
  523. help
  524. Enabling this feature will cause a message to be printed when the P4
  525. enters thermal throttling.
  526. config VM86
  527. bool "Enable VM86 support" if EMBEDDED
  528. default y
  529. depends on X86_32
  530. help
  531. This option is required by programs like DOSEMU to run 16-bit legacy
  532. code on X86 processors. It also may be needed by software like
  533. XFree86 to initialize some video cards via BIOS. Disabling this
  534. option saves about 6k.
  535. config TOSHIBA
  536. tristate "Toshiba Laptop support"
  537. depends on X86_32
  538. ---help---
  539. This adds a driver to safely access the System Management Mode of
  540. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  541. not work on models with a Phoenix BIOS. The System Management Mode
  542. is used to set the BIOS and power saving options on Toshiba portables.
  543. For information on utilities to make use of this driver see the
  544. Toshiba Linux utilities web site at:
  545. <http://www.buzzard.org.uk/toshiba/>.
  546. Say Y if you intend to run this kernel on a Toshiba portable.
  547. Say N otherwise.
  548. config I8K
  549. tristate "Dell laptop support"
  550. ---help---
  551. This adds a driver to safely access the System Management Mode
  552. of the CPU on the Dell Inspiron 8000. The System Management Mode
  553. is used to read cpu temperature and cooling fan status and to
  554. control the fans on the I8K portables.
  555. This driver has been tested only on the Inspiron 8000 but it may
  556. also work with other Dell laptops. You can force loading on other
  557. models by passing the parameter `force=1' to the module. Use at
  558. your own risk.
  559. For information on utilities to make use of this driver see the
  560. I8K Linux utilities web site at:
  561. <http://people.debian.org/~dz/i8k/>
  562. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  563. Say N otherwise.
  564. config X86_REBOOTFIXUPS
  565. def_bool n
  566. prompt "Enable X86 board specific fixups for reboot"
  567. depends on X86_32 && X86
  568. ---help---
  569. This enables chipset and/or board specific fixups to be done
  570. in order to get reboot to work correctly. This is only needed on
  571. some combinations of hardware and BIOS. The symptom, for which
  572. this config is intended, is when reboot ends with a stalled/hung
  573. system.
  574. Currently, the only fixup is for the Geode machines using
  575. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  576. Say Y if you want to enable the fixup. Currently, it's safe to
  577. enable this option even if you don't need it.
  578. Say N otherwise.
  579. config MICROCODE
  580. tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
  581. select FW_LOADER
  582. ---help---
  583. If you say Y here, you will be able to update the microcode on
  584. Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
  585. Pentium III, Pentium 4, Xeon etc. You will obviously need the
  586. actual microcode binary data itself which is not shipped with the
  587. Linux kernel.
  588. For latest news and information on obtaining all the required
  589. ingredients for this driver, check:
  590. <http://www.urbanmyth.org/microcode/>.
  591. To compile this driver as a module, choose M here: the
  592. module will be called microcode.
  593. config MICROCODE_OLD_INTERFACE
  594. def_bool y
  595. depends on MICROCODE
  596. config X86_MSR
  597. tristate "/dev/cpu/*/msr - Model-specific register support"
  598. help
  599. This device gives privileged processes access to the x86
  600. Model-Specific Registers (MSRs). It is a character device with
  601. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  602. MSR accesses are directed to a specific CPU on multi-processor
  603. systems.
  604. config X86_CPUID
  605. tristate "/dev/cpu/*/cpuid - CPU information support"
  606. help
  607. This device gives processes access to the x86 CPUID instruction to
  608. be executed on a specific processor. It is a character device
  609. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  610. /dev/cpu/31/cpuid.
  611. choice
  612. prompt "High Memory Support"
  613. default HIGHMEM4G if !X86_NUMAQ
  614. default HIGHMEM64G if X86_NUMAQ
  615. depends on X86_32
  616. config NOHIGHMEM
  617. bool "off"
  618. depends on !X86_NUMAQ
  619. ---help---
  620. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  621. However, the address space of 32-bit x86 processors is only 4
  622. Gigabytes large. That means that, if you have a large amount of
  623. physical memory, not all of it can be "permanently mapped" by the
  624. kernel. The physical memory that's not permanently mapped is called
  625. "high memory".
  626. If you are compiling a kernel which will never run on a machine with
  627. more than 1 Gigabyte total physical RAM, answer "off" here (default
  628. choice and suitable for most users). This will result in a "3GB/1GB"
  629. split: 3GB are mapped so that each process sees a 3GB virtual memory
  630. space and the remaining part of the 4GB virtual memory space is used
  631. by the kernel to permanently map as much physical memory as
  632. possible.
  633. If the machine has between 1 and 4 Gigabytes physical RAM, then
  634. answer "4GB" here.
  635. If more than 4 Gigabytes is used then answer "64GB" here. This
  636. selection turns Intel PAE (Physical Address Extension) mode on.
  637. PAE implements 3-level paging on IA32 processors. PAE is fully
  638. supported by Linux, PAE mode is implemented on all recent Intel
  639. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  640. then the kernel will not boot on CPUs that don't support PAE!
  641. The actual amount of total physical memory will either be
  642. auto detected or can be forced by using a kernel command line option
  643. such as "mem=256M". (Try "man bootparam" or see the documentation of
  644. your boot loader (lilo or loadlin) about how to pass options to the
  645. kernel at boot time.)
  646. If unsure, say "off".
  647. config HIGHMEM4G
  648. bool "4GB"
  649. depends on !X86_NUMAQ
  650. help
  651. Select this if you have a 32-bit processor and between 1 and 4
  652. gigabytes of physical RAM.
  653. config HIGHMEM64G
  654. bool "64GB"
  655. depends on !M386 && !M486
  656. select X86_PAE
  657. help
  658. Select this if you have a 32-bit processor and more than 4
  659. gigabytes of physical RAM.
  660. endchoice
  661. choice
  662. depends on EXPERIMENTAL
  663. prompt "Memory split" if EMBEDDED
  664. default VMSPLIT_3G
  665. depends on X86_32
  666. help
  667. Select the desired split between kernel and user memory.
  668. If the address range available to the kernel is less than the
  669. physical memory installed, the remaining memory will be available
  670. as "high memory". Accessing high memory is a little more costly
  671. than low memory, as it needs to be mapped into the kernel first.
  672. Note that increasing the kernel address space limits the range
  673. available to user programs, making the address space there
  674. tighter. Selecting anything other than the default 3G/1G split
  675. will also likely make your kernel incompatible with binary-only
  676. kernel modules.
  677. If you are not absolutely sure what you are doing, leave this
  678. option alone!
  679. config VMSPLIT_3G
  680. bool "3G/1G user/kernel split"
  681. config VMSPLIT_3G_OPT
  682. depends on !X86_PAE
  683. bool "3G/1G user/kernel split (for full 1G low memory)"
  684. config VMSPLIT_2G
  685. bool "2G/2G user/kernel split"
  686. config VMSPLIT_2G_OPT
  687. depends on !X86_PAE
  688. bool "2G/2G user/kernel split (for full 2G low memory)"
  689. config VMSPLIT_1G
  690. bool "1G/3G user/kernel split"
  691. endchoice
  692. config PAGE_OFFSET
  693. hex
  694. default 0xB0000000 if VMSPLIT_3G_OPT
  695. default 0x80000000 if VMSPLIT_2G
  696. default 0x78000000 if VMSPLIT_2G_OPT
  697. default 0x40000000 if VMSPLIT_1G
  698. default 0xC0000000
  699. depends on X86_32
  700. config HIGHMEM
  701. def_bool y
  702. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  703. config X86_PAE
  704. def_bool n
  705. prompt "PAE (Physical Address Extension) Support"
  706. depends on X86_32 && !HIGHMEM4G
  707. select RESOURCES_64BIT
  708. help
  709. PAE is required for NX support, and furthermore enables
  710. larger swapspace support for non-overcommit purposes. It
  711. has the cost of more pagetable lookup overhead, and also
  712. consumes more pagetable space per process.
  713. # Common NUMA Features
  714. config NUMA
  715. bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
  716. depends on SMP
  717. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
  718. default n if X86_PC
  719. default y if (X86_NUMAQ || X86_SUMMIT)
  720. help
  721. Enable NUMA (Non Uniform Memory Access) support.
  722. The kernel will try to allocate memory used by a CPU on the
  723. local memory controller of the CPU and add some more
  724. NUMA awareness to the kernel.
  725. For i386 this is currently highly experimental and should be only
  726. used for kernel development. It might also cause boot failures.
  727. For x86_64 this is recommended on all multiprocessor Opteron systems.
  728. If the system is EM64T, you should say N unless your system is
  729. EM64T NUMA.
  730. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  731. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  732. config K8_NUMA
  733. def_bool y
  734. prompt "Old style AMD Opteron NUMA detection"
  735. depends on X86_64 && NUMA && PCI
  736. help
  737. Enable K8 NUMA node topology detection. You should say Y here if
  738. you have a multi processor AMD K8 system. This uses an old
  739. method to read the NUMA configuration directly from the builtin
  740. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  741. instead, which also takes priority if both are compiled in.
  742. config X86_64_ACPI_NUMA
  743. def_bool y
  744. prompt "ACPI NUMA detection"
  745. depends on X86_64 && NUMA && ACPI && PCI
  746. select ACPI_NUMA
  747. help
  748. Enable ACPI SRAT based node topology detection.
  749. # Some NUMA nodes have memory ranges that span
  750. # other nodes. Even though a pfn is valid and
  751. # between a node's start and end pfns, it may not
  752. # reside on that node. See memmap_init_zone()
  753. # for details.
  754. config NODES_SPAN_OTHER_NODES
  755. def_bool y
  756. depends on X86_64_ACPI_NUMA
  757. config NUMA_EMU
  758. bool "NUMA emulation"
  759. depends on X86_64 && NUMA
  760. help
  761. Enable NUMA emulation. A flat machine will be split
  762. into virtual nodes when booted with "numa=fake=N", where N is the
  763. number of nodes. This is only useful for debugging.
  764. config NODES_SHIFT
  765. int "Max num nodes shift(1-15)"
  766. range 1 15 if X86_64
  767. default "6" if X86_64
  768. default "4" if X86_NUMAQ
  769. default "3"
  770. depends on NEED_MULTIPLE_NODES
  771. config HAVE_ARCH_BOOTMEM_NODE
  772. def_bool y
  773. depends on X86_32 && NUMA
  774. config ARCH_HAVE_MEMORY_PRESENT
  775. def_bool y
  776. depends on X86_32 && DISCONTIGMEM
  777. config NEED_NODE_MEMMAP_SIZE
  778. def_bool y
  779. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  780. config HAVE_ARCH_ALLOC_REMAP
  781. def_bool y
  782. depends on X86_32 && NUMA
  783. config ARCH_FLATMEM_ENABLE
  784. def_bool y
  785. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
  786. config ARCH_DISCONTIGMEM_ENABLE
  787. def_bool y
  788. depends on NUMA && X86_32
  789. config ARCH_DISCONTIGMEM_DEFAULT
  790. def_bool y
  791. depends on NUMA && X86_32
  792. config ARCH_SPARSEMEM_DEFAULT
  793. def_bool y
  794. depends on X86_64
  795. config ARCH_SPARSEMEM_ENABLE
  796. def_bool y
  797. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
  798. select SPARSEMEM_STATIC if X86_32
  799. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  800. config ARCH_SELECT_MEMORY_MODEL
  801. def_bool y
  802. depends on ARCH_SPARSEMEM_ENABLE
  803. config ARCH_MEMORY_PROBE
  804. def_bool X86_64
  805. depends on MEMORY_HOTPLUG
  806. source "mm/Kconfig"
  807. config HIGHPTE
  808. bool "Allocate 3rd-level pagetables from highmem"
  809. depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
  810. help
  811. The VM uses one page table entry for each page of physical memory.
  812. For systems with a lot of RAM, this can be wasteful of precious
  813. low memory. Setting this option will put user-space page table
  814. entries in high memory.
  815. config MATH_EMULATION
  816. bool
  817. prompt "Math emulation" if X86_32
  818. ---help---
  819. Linux can emulate a math coprocessor (used for floating point
  820. operations) if you don't have one. 486DX and Pentium processors have
  821. a math coprocessor built in, 486SX and 386 do not, unless you added
  822. a 487DX or 387, respectively. (The messages during boot time can
  823. give you some hints here ["man dmesg"].) Everyone needs either a
  824. coprocessor or this emulation.
  825. If you don't have a math coprocessor, you need to say Y here; if you
  826. say Y here even though you have a coprocessor, the coprocessor will
  827. be used nevertheless. (This behavior can be changed with the kernel
  828. command line option "no387", which comes handy if your coprocessor
  829. is broken. Try "man bootparam" or see the documentation of your boot
  830. loader (lilo or loadlin) about how to pass options to the kernel at
  831. boot time.) This means that it is a good idea to say Y here if you
  832. intend to use this kernel on different machines.
  833. More information about the internals of the Linux math coprocessor
  834. emulation can be found in <file:arch/x86/math-emu/README>.
  835. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  836. kernel, it won't hurt.
  837. config MTRR
  838. bool "MTRR (Memory Type Range Register) support"
  839. ---help---
  840. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  841. the Memory Type Range Registers (MTRRs) may be used to control
  842. processor access to memory ranges. This is most useful if you have
  843. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  844. allows bus write transfers to be combined into a larger transfer
  845. before bursting over the PCI/AGP bus. This can increase performance
  846. of image write operations 2.5 times or more. Saying Y here creates a
  847. /proc/mtrr file which may be used to manipulate your processor's
  848. MTRRs. Typically the X server should use this.
  849. This code has a reasonably generic interface so that similar
  850. control registers on other processors can be easily supported
  851. as well:
  852. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  853. Registers (ARRs) which provide a similar functionality to MTRRs. For
  854. these, the ARRs are used to emulate the MTRRs.
  855. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  856. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  857. write-combining. All of these processors are supported by this code
  858. and it makes sense to say Y here if you have one of them.
  859. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  860. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  861. can lead to all sorts of problems, so it's good to say Y here.
  862. You can safely say Y even if your machine doesn't have MTRRs, you'll
  863. just add about 9 KB to your kernel.
  864. See <file:Documentation/mtrr.txt> for more information.
  865. config X86_PAT
  866. bool
  867. prompt "x86 PAT support"
  868. depends on MTRR
  869. help
  870. Use PAT attributes to setup page level cache control.
  871. PATs are the modern equivalents of MTRRs and are much more
  872. flexible than MTRRs.
  873. Say N here if you see bootup problems (boot crash, boot hang,
  874. spontaneous reboots) or a non-working video driver.
  875. If unsure, say Y.
  876. config EFI
  877. def_bool n
  878. prompt "EFI runtime service support"
  879. depends on ACPI
  880. ---help---
  881. This enables the kernel to use EFI runtime services that are
  882. available (such as the EFI variable services).
  883. This option is only useful on systems that have EFI firmware.
  884. In addition, you should use the latest ELILO loader available
  885. at <http://elilo.sourceforge.net> in order to take advantage
  886. of EFI runtime services. However, even with this option, the
  887. resultant kernel should continue to boot on existing non-EFI
  888. platforms.
  889. config IRQBALANCE
  890. def_bool y
  891. prompt "Enable kernel irq balancing"
  892. depends on X86_32 && SMP && X86_IO_APIC
  893. help
  894. The default yes will allow the kernel to do irq load balancing.
  895. Saying no will keep the kernel from doing irq load balancing.
  896. config SECCOMP
  897. def_bool y
  898. prompt "Enable seccomp to safely compute untrusted bytecode"
  899. depends on PROC_FS
  900. help
  901. This kernel feature is useful for number crunching applications
  902. that may need to compute untrusted bytecode during their
  903. execution. By using pipes or other transports made available to
  904. the process as file descriptors supporting the read/write
  905. syscalls, it's possible to isolate those applications in
  906. their own address space using seccomp. Once seccomp is
  907. enabled via /proc/<pid>/seccomp, it cannot be disabled
  908. and the task is only allowed to execute a few safe syscalls
  909. defined by each seccomp mode.
  910. If unsure, say Y. Only embedded should say N here.
  911. config CC_STACKPROTECTOR
  912. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  913. depends on X86_64 && EXPERIMENTAL && BROKEN
  914. help
  915. This option turns on the -fstack-protector GCC feature. This
  916. feature puts, at the beginning of critical functions, a canary
  917. value on the stack just before the return address, and validates
  918. the value just before actually returning. Stack based buffer
  919. overflows (that need to overwrite this return address) now also
  920. overwrite the canary, which gets detected and the attack is then
  921. neutralized via a kernel panic.
  922. This feature requires gcc version 4.2 or above, or a distribution
  923. gcc with the feature backported. Older versions are automatically
  924. detected and for those versions, this configuration option is ignored.
  925. config CC_STACKPROTECTOR_ALL
  926. bool "Use stack-protector for all functions"
  927. depends on CC_STACKPROTECTOR
  928. help
  929. Normally, GCC only inserts the canary value protection for
  930. functions that use large-ish on-stack buffers. By enabling
  931. this option, GCC will be asked to do this for ALL functions.
  932. source kernel/Kconfig.hz
  933. config KEXEC
  934. bool "kexec system call"
  935. depends on X86_64 || X86_BIOS_REBOOT
  936. help
  937. kexec is a system call that implements the ability to shutdown your
  938. current kernel, and to start another kernel. It is like a reboot
  939. but it is independent of the system firmware. And like a reboot
  940. you can start any kernel with it, not just Linux.
  941. The name comes from the similarity to the exec system call.
  942. It is an ongoing process to be certain the hardware in a machine
  943. is properly shutdown, so do not be surprised if this code does not
  944. initially work for you. It may help to enable device hotplugging
  945. support. As of this writing the exact hardware interface is
  946. strongly in flux, so no good recommendation can be made.
  947. config CRASH_DUMP
  948. bool "kernel crash dumps (EXPERIMENTAL)"
  949. depends on EXPERIMENTAL
  950. depends on X86_64 || (X86_32 && HIGHMEM)
  951. help
  952. Generate crash dump after being started by kexec.
  953. This should be normally only set in special crash dump kernels
  954. which are loaded in the main kernel with kexec-tools into
  955. a specially reserved region and then later executed after
  956. a crash by kdump/kexec. The crash dump kernel must be compiled
  957. to a memory address not used by the main kernel or BIOS using
  958. PHYSICAL_START, or it must be built as a relocatable image
  959. (CONFIG_RELOCATABLE=y).
  960. For more details see Documentation/kdump/kdump.txt
  961. config PHYSICAL_START
  962. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  963. default "0x1000000" if X86_NUMAQ
  964. default "0x200000" if X86_64
  965. default "0x100000"
  966. help
  967. This gives the physical address where the kernel is loaded.
  968. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  969. bzImage will decompress itself to above physical address and
  970. run from there. Otherwise, bzImage will run from the address where
  971. it has been loaded by the boot loader and will ignore above physical
  972. address.
  973. In normal kdump cases one does not have to set/change this option
  974. as now bzImage can be compiled as a completely relocatable image
  975. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  976. address. This option is mainly useful for the folks who don't want
  977. to use a bzImage for capturing the crash dump and want to use a
  978. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  979. to be specifically compiled to run from a specific memory area
  980. (normally a reserved region) and this option comes handy.
  981. So if you are using bzImage for capturing the crash dump, leave
  982. the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
  983. Otherwise if you plan to use vmlinux for capturing the crash dump
  984. change this value to start of the reserved region (Typically 16MB
  985. 0x1000000). In other words, it can be set based on the "X" value as
  986. specified in the "crashkernel=YM@XM" command line boot parameter
  987. passed to the panic-ed kernel. Typically this parameter is set as
  988. crashkernel=64M@16M. Please take a look at
  989. Documentation/kdump/kdump.txt for more details about crash dumps.
  990. Usage of bzImage for capturing the crash dump is recommended as
  991. one does not have to build two kernels. Same kernel can be used
  992. as production kernel and capture kernel. Above option should have
  993. gone away after relocatable bzImage support is introduced. But it
  994. is present because there are users out there who continue to use
  995. vmlinux for dump capture. This option should go away down the
  996. line.
  997. Don't change this unless you know what you are doing.
  998. config RELOCATABLE
  999. bool "Build a relocatable kernel (EXPERIMENTAL)"
  1000. depends on EXPERIMENTAL
  1001. help
  1002. This builds a kernel image that retains relocation information
  1003. so it can be loaded someplace besides the default 1MB.
  1004. The relocations tend to make the kernel binary about 10% larger,
  1005. but are discarded at runtime.
  1006. One use is for the kexec on panic case where the recovery kernel
  1007. must live at a different physical address than the primary
  1008. kernel.
  1009. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1010. it has been loaded at and the compile time physical address
  1011. (CONFIG_PHYSICAL_START) is ignored.
  1012. config PHYSICAL_ALIGN
  1013. hex
  1014. prompt "Alignment value to which kernel should be aligned" if X86_32
  1015. default "0x100000" if X86_32
  1016. default "0x200000" if X86_64
  1017. range 0x2000 0x400000
  1018. help
  1019. This value puts the alignment restrictions on physical address
  1020. where kernel is loaded and run from. Kernel is compiled for an
  1021. address which meets above alignment restriction.
  1022. If bootloader loads the kernel at a non-aligned address and
  1023. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1024. address aligned to above value and run from there.
  1025. If bootloader loads the kernel at a non-aligned address and
  1026. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1027. load address and decompress itself to the address it has been
  1028. compiled for and run from there. The address for which kernel is
  1029. compiled already meets above alignment restrictions. Hence the
  1030. end result is that kernel runs from a physical address meeting
  1031. above alignment restrictions.
  1032. Don't change this unless you know what you are doing.
  1033. config HOTPLUG_CPU
  1034. bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
  1035. depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
  1036. ---help---
  1037. Say Y here to experiment with turning CPUs off and on, and to
  1038. enable suspend on SMP systems. CPUs can be controlled through
  1039. /sys/devices/system/cpu.
  1040. Say N if you want to disable CPU hotplug and don't need to
  1041. suspend.
  1042. config COMPAT_VDSO
  1043. def_bool y
  1044. prompt "Compat VDSO support"
  1045. depends on X86_32 || IA32_EMULATION
  1046. help
  1047. Map the 32-bit VDSO to the predictable old-style address too.
  1048. ---help---
  1049. Say N here if you are running a sufficiently recent glibc
  1050. version (2.3.3 or later), to remove the high-mapped
  1051. VDSO mapping and to exclusively use the randomized VDSO.
  1052. If unsure, say Y.
  1053. endmenu
  1054. config ARCH_ENABLE_MEMORY_HOTPLUG
  1055. def_bool y
  1056. depends on X86_64 || (X86_32 && HIGHMEM)
  1057. config HAVE_ARCH_EARLY_PFN_TO_NID
  1058. def_bool X86_64
  1059. depends on NUMA
  1060. menu "Power management options"
  1061. depends on !X86_VOYAGER
  1062. config ARCH_HIBERNATION_HEADER
  1063. def_bool y
  1064. depends on X86_64 && HIBERNATION
  1065. source "kernel/power/Kconfig"
  1066. source "drivers/acpi/Kconfig"
  1067. config X86_APM_BOOT
  1068. bool
  1069. default y
  1070. depends on APM || APM_MODULE
  1071. menuconfig APM
  1072. tristate "APM (Advanced Power Management) BIOS support"
  1073. depends on X86_32 && PM_SLEEP && !X86_VISWS
  1074. ---help---
  1075. APM is a BIOS specification for saving power using several different
  1076. techniques. This is mostly useful for battery powered laptops with
  1077. APM compliant BIOSes. If you say Y here, the system time will be
  1078. reset after a RESUME operation, the /proc/apm device will provide
  1079. battery status information, and user-space programs will receive
  1080. notification of APM "events" (e.g. battery status change).
  1081. If you select "Y" here, you can disable actual use of the APM
  1082. BIOS by passing the "apm=off" option to the kernel at boot time.
  1083. Note that the APM support is almost completely disabled for
  1084. machines with more than one CPU.
  1085. In order to use APM, you will need supporting software. For location
  1086. and more information, read <file:Documentation/power/pm.txt> and the
  1087. Battery Powered Linux mini-HOWTO, available from
  1088. <http://www.tldp.org/docs.html#howto>.
  1089. This driver does not spin down disk drives (see the hdparm(8)
  1090. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1091. VESA-compliant "green" monitors.
  1092. This driver does not support the TI 4000M TravelMate and the ACER
  1093. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1094. desktop machines also don't have compliant BIOSes, and this driver
  1095. may cause those machines to panic during the boot phase.
  1096. Generally, if you don't have a battery in your machine, there isn't
  1097. much point in using this driver and you should say N. If you get
  1098. random kernel OOPSes or reboots that don't seem to be related to
  1099. anything, try disabling/enabling this option (or disabling/enabling
  1100. APM in your BIOS).
  1101. Some other things you should try when experiencing seemingly random,
  1102. "weird" problems:
  1103. 1) make sure that you have enough swap space and that it is
  1104. enabled.
  1105. 2) pass the "no-hlt" option to the kernel
  1106. 3) switch on floating point emulation in the kernel and pass
  1107. the "no387" option to the kernel
  1108. 4) pass the "floppy=nodma" option to the kernel
  1109. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1110. all but the first 4 MB of RAM)
  1111. 6) make sure that the CPU is not over clocked.
  1112. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1113. 8) disable the cache from your BIOS settings
  1114. 9) install a fan for the video card or exchange video RAM
  1115. 10) install a better fan for the CPU
  1116. 11) exchange RAM chips
  1117. 12) exchange the motherboard.
  1118. To compile this driver as a module, choose M here: the
  1119. module will be called apm.
  1120. if APM
  1121. config APM_IGNORE_USER_SUSPEND
  1122. bool "Ignore USER SUSPEND"
  1123. help
  1124. This option will ignore USER SUSPEND requests. On machines with a
  1125. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1126. series notebooks, it is necessary to say Y because of a BIOS bug.
  1127. config APM_DO_ENABLE
  1128. bool "Enable PM at boot time"
  1129. ---help---
  1130. Enable APM features at boot time. From page 36 of the APM BIOS
  1131. specification: "When disabled, the APM BIOS does not automatically
  1132. power manage devices, enter the Standby State, enter the Suspend
  1133. State, or take power saving steps in response to CPU Idle calls."
  1134. This driver will make CPU Idle calls when Linux is idle (unless this
  1135. feature is turned off -- see "Do CPU IDLE calls", below). This
  1136. should always save battery power, but more complicated APM features
  1137. will be dependent on your BIOS implementation. You may need to turn
  1138. this option off if your computer hangs at boot time when using APM
  1139. support, or if it beeps continuously instead of suspending. Turn
  1140. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1141. T400CDT. This is off by default since most machines do fine without
  1142. this feature.
  1143. config APM_CPU_IDLE
  1144. bool "Make CPU Idle calls when idle"
  1145. help
  1146. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1147. On some machines, this can activate improved power savings, such as
  1148. a slowed CPU clock rate, when the machine is idle. These idle calls
  1149. are made after the idle loop has run for some length of time (e.g.,
  1150. 333 mS). On some machines, this will cause a hang at boot time or
  1151. whenever the CPU becomes idle. (On machines with more than one CPU,
  1152. this option does nothing.)
  1153. config APM_DISPLAY_BLANK
  1154. bool "Enable console blanking using APM"
  1155. help
  1156. Enable console blanking using the APM. Some laptops can use this to
  1157. turn off the LCD backlight when the screen blanker of the Linux
  1158. virtual console blanks the screen. Note that this is only used by
  1159. the virtual console screen blanker, and won't turn off the backlight
  1160. when using the X Window system. This also doesn't have anything to
  1161. do with your VESA-compliant power-saving monitor. Further, this
  1162. option doesn't work for all laptops -- it might not turn off your
  1163. backlight at all, or it might print a lot of errors to the console,
  1164. especially if you are using gpm.
  1165. config APM_ALLOW_INTS
  1166. bool "Allow interrupts during APM BIOS calls"
  1167. help
  1168. Normally we disable external interrupts while we are making calls to
  1169. the APM BIOS as a measure to lessen the effects of a badly behaving
  1170. BIOS implementation. The BIOS should reenable interrupts if it
  1171. needs to. Unfortunately, some BIOSes do not -- especially those in
  1172. many of the newer IBM Thinkpads. If you experience hangs when you
  1173. suspend, try setting this to Y. Otherwise, say N.
  1174. config APM_REAL_MODE_POWER_OFF
  1175. bool "Use real mode APM BIOS call to power off"
  1176. help
  1177. Use real mode APM BIOS calls to switch off the computer. This is
  1178. a work-around for a number of buggy BIOSes. Switch this option on if
  1179. your computer crashes instead of powering off properly.
  1180. endif # APM
  1181. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1182. source "drivers/cpuidle/Kconfig"
  1183. endmenu
  1184. menu "Bus options (PCI etc.)"
  1185. config PCI
  1186. bool "PCI support" if !X86_VISWS && !X86_VSMP
  1187. depends on !X86_VOYAGER
  1188. default y
  1189. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1190. help
  1191. Find out whether you have a PCI motherboard. PCI is the name of a
  1192. bus system, i.e. the way the CPU talks to the other stuff inside
  1193. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1194. VESA. If you have PCI, say Y, otherwise N.
  1195. choice
  1196. prompt "PCI access mode"
  1197. depends on X86_32 && PCI && !X86_VISWS
  1198. default PCI_GOANY
  1199. ---help---
  1200. On PCI systems, the BIOS can be used to detect the PCI devices and
  1201. determine their configuration. However, some old PCI motherboards
  1202. have BIOS bugs and may crash if this is done. Also, some embedded
  1203. PCI-based systems don't have any BIOS at all. Linux can also try to
  1204. detect the PCI hardware directly without using the BIOS.
  1205. With this option, you can specify how Linux should detect the
  1206. PCI devices. If you choose "BIOS", the BIOS will be used,
  1207. if you choose "Direct", the BIOS won't be used, and if you
  1208. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1209. If you choose "Any", the kernel will try MMCONFIG, then the
  1210. direct access method and falls back to the BIOS if that doesn't
  1211. work. If unsure, go with the default, which is "Any".
  1212. config PCI_GOBIOS
  1213. bool "BIOS"
  1214. config PCI_GOMMCONFIG
  1215. bool "MMConfig"
  1216. config PCI_GODIRECT
  1217. bool "Direct"
  1218. config PCI_GOANY
  1219. bool "Any"
  1220. endchoice
  1221. config PCI_BIOS
  1222. def_bool y
  1223. depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
  1224. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1225. config PCI_DIRECT
  1226. def_bool y
  1227. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
  1228. config PCI_MMCONFIG
  1229. def_bool y
  1230. depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  1231. config PCI_DOMAINS
  1232. def_bool y
  1233. depends on PCI
  1234. config PCI_MMCONFIG
  1235. bool "Support mmconfig PCI config space access"
  1236. depends on X86_64 && PCI && ACPI
  1237. config DMAR
  1238. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1239. depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
  1240. help
  1241. DMA remapping (DMAR) devices support enables independent address
  1242. translations for Direct Memory Access (DMA) from devices.
  1243. These DMA remapping devices are reported via ACPI tables
  1244. and include PCI device scope covered by these DMA
  1245. remapping devices.
  1246. config DMAR_GFX_WA
  1247. def_bool y
  1248. prompt "Support for Graphics workaround"
  1249. depends on DMAR
  1250. help
  1251. Current Graphics drivers tend to use physical address
  1252. for DMA and avoid using DMA APIs. Setting this config
  1253. option permits the IOMMU driver to set a unity map for
  1254. all the OS-visible memory. Hence the driver can continue
  1255. to use physical addresses for DMA.
  1256. config DMAR_FLOPPY_WA
  1257. def_bool y
  1258. depends on DMAR
  1259. help
  1260. Floppy disk drivers are know to bypass DMA API calls
  1261. thereby failing to work when IOMMU is enabled. This
  1262. workaround will setup a 1:1 mapping for the first
  1263. 16M to make floppy (an ISA device) work.
  1264. source "drivers/pci/pcie/Kconfig"
  1265. source "drivers/pci/Kconfig"
  1266. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1267. config ISA_DMA_API
  1268. def_bool y
  1269. if X86_32
  1270. config ISA
  1271. bool "ISA support"
  1272. depends on !(X86_VOYAGER || X86_VISWS)
  1273. help
  1274. Find out whether you have ISA slots on your motherboard. ISA is the
  1275. name of a bus system, i.e. the way the CPU talks to the other stuff
  1276. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1277. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1278. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1279. config EISA
  1280. bool "EISA support"
  1281. depends on ISA
  1282. ---help---
  1283. The Extended Industry Standard Architecture (EISA) bus was
  1284. developed as an open alternative to the IBM MicroChannel bus.
  1285. The EISA bus provided some of the features of the IBM MicroChannel
  1286. bus while maintaining backward compatibility with cards made for
  1287. the older ISA bus. The EISA bus saw limited use between 1988 and
  1288. 1995 when it was made obsolete by the PCI bus.
  1289. Say Y here if you are building a kernel for an EISA-based machine.
  1290. Otherwise, say N.
  1291. source "drivers/eisa/Kconfig"
  1292. config MCA
  1293. bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
  1294. default y if X86_VOYAGER
  1295. help
  1296. MicroChannel Architecture is found in some IBM PS/2 machines and
  1297. laptops. It is a bus system similar to PCI or ISA. See
  1298. <file:Documentation/mca.txt> (and especially the web page given
  1299. there) before attempting to build an MCA bus kernel.
  1300. source "drivers/mca/Kconfig"
  1301. config SCx200
  1302. tristate "NatSemi SCx200 support"
  1303. depends on !X86_VOYAGER
  1304. help
  1305. This provides basic support for National Semiconductor's
  1306. (now AMD's) Geode processors. The driver probes for the
  1307. PCI-IDs of several on-chip devices, so its a good dependency
  1308. for other scx200_* drivers.
  1309. If compiled as a module, the driver is named scx200.
  1310. config SCx200HR_TIMER
  1311. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1312. depends on SCx200 && GENERIC_TIME
  1313. default y
  1314. help
  1315. This driver provides a clocksource built upon the on-chip
  1316. 27MHz high-resolution timer. Its also a workaround for
  1317. NSC Geode SC-1100's buggy TSC, which loses time when the
  1318. processor goes idle (as is done by the scheduler). The
  1319. other workaround is idle=poll boot option.
  1320. config GEODE_MFGPT_TIMER
  1321. def_bool y
  1322. prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
  1323. depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
  1324. help
  1325. This driver provides a clock event source based on the MFGPT
  1326. timer(s) in the CS5535 and CS5536 companion chip for the geode.
  1327. MFGPTs have a better resolution and max interval than the
  1328. generic PIT, and are suitable for use as high-res timers.
  1329. endif # X86_32
  1330. config K8_NB
  1331. def_bool y
  1332. depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
  1333. source "drivers/pcmcia/Kconfig"
  1334. source "drivers/pci/hotplug/Kconfig"
  1335. endmenu
  1336. menu "Executable file formats / Emulations"
  1337. source "fs/Kconfig.binfmt"
  1338. config IA32_EMULATION
  1339. bool "IA32 Emulation"
  1340. depends on X86_64
  1341. select COMPAT_BINFMT_ELF
  1342. help
  1343. Include code to run 32-bit programs under a 64-bit kernel. You should
  1344. likely turn this on, unless you're 100% sure that you don't have any
  1345. 32-bit programs left.
  1346. config IA32_AOUT
  1347. tristate "IA32 a.out support"
  1348. depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
  1349. help
  1350. Support old a.out binaries in the 32bit emulation.
  1351. config COMPAT
  1352. def_bool y
  1353. depends on IA32_EMULATION
  1354. config COMPAT_FOR_U64_ALIGNMENT
  1355. def_bool COMPAT
  1356. depends on X86_64
  1357. config SYSVIPC_COMPAT
  1358. def_bool y
  1359. depends on X86_64 && COMPAT && SYSVIPC
  1360. endmenu
  1361. source "net/Kconfig"
  1362. source "drivers/Kconfig"
  1363. source "drivers/firmware/Kconfig"
  1364. source "fs/Kconfig"
  1365. source "arch/x86/Kconfig.debug"
  1366. source "security/Kconfig"
  1367. source "crypto/Kconfig"
  1368. source "arch/x86/kvm/Kconfig"
  1369. source "lib/Kconfig"