Kconfig 38 KB

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  1. #
  2. # For a description of the syntax of this configuration file,
  3. # see Documentation/kbuild/kconfig-language.txt.
  4. #
  5. mainmenu "Linux Kernel Configuration"
  6. config X86_32
  7. bool
  8. default y
  9. help
  10. This is Linux's home port. Linux was originally native to the Intel
  11. 386, and runs on all the later x86 processors including the Intel
  12. 486, 586, Pentiums, and various instruction-set-compatible chips by
  13. AMD, Cyrix, and others.
  14. config GENERIC_TIME
  15. bool
  16. default y
  17. config SEMAPHORE_SLEEPERS
  18. bool
  19. default y
  20. config X86
  21. bool
  22. default y
  23. config MMU
  24. bool
  25. default y
  26. config SBUS
  27. bool
  28. config GENERIC_ISA_DMA
  29. bool
  30. default y
  31. config GENERIC_IOMAP
  32. bool
  33. default y
  34. config GENERIC_HWEIGHT
  35. bool
  36. default y
  37. config ARCH_MAY_HAVE_PC_FDC
  38. bool
  39. default y
  40. config DMI
  41. bool
  42. default y
  43. source "init/Kconfig"
  44. menu "Processor type and features"
  45. config SMP
  46. bool "Symmetric multi-processing support"
  47. ---help---
  48. This enables support for systems with more than one CPU. If you have
  49. a system with only one CPU, like most personal computers, say N. If
  50. you have a system with more than one CPU, say Y.
  51. If you say N here, the kernel will run on single and multiprocessor
  52. machines, but will use only one CPU of a multiprocessor machine. If
  53. you say Y here, the kernel will run on many, but not all,
  54. singleprocessor machines. On a singleprocessor machine, the kernel
  55. will run faster if you say N here.
  56. Note that if you say Y here and choose architecture "586" or
  57. "Pentium" under "Processor family", the kernel will not work on 486
  58. architectures. Similarly, multiprocessor kernels for the "PPro"
  59. architecture may not work on all Pentium based boards.
  60. People using multiprocessor machines who say Y here should also say
  61. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  62. Management" code will be disabled if you say Y here.
  63. See also the <file:Documentation/smp.txt>,
  64. <file:Documentation/i386/IO-APIC.txt>,
  65. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  66. <http://www.tldp.org/docs.html#howto>.
  67. If you don't know what to do here, say N.
  68. choice
  69. prompt "Subarchitecture Type"
  70. default X86_PC
  71. config X86_PC
  72. bool "PC-compatible"
  73. help
  74. Choose this option if your computer is a standard PC or compatible.
  75. config X86_ELAN
  76. bool "AMD Elan"
  77. help
  78. Select this for an AMD Elan processor.
  79. Do not use this option for K6/Athlon/Opteron processors!
  80. If unsure, choose "PC-compatible" instead.
  81. config X86_VOYAGER
  82. bool "Voyager (NCR)"
  83. help
  84. Voyager is an MCA-based 32-way capable SMP architecture proprietary
  85. to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
  86. *** WARNING ***
  87. If you do not specifically know you have a Voyager based machine,
  88. say N here, otherwise the kernel you build will not be bootable.
  89. config X86_NUMAQ
  90. bool "NUMAQ (IBM/Sequent)"
  91. select SMP
  92. select NUMA
  93. help
  94. This option is used for getting Linux to run on a (IBM/Sequent) NUMA
  95. multiquad box. This changes the way that processors are bootstrapped,
  96. and uses Clustered Logical APIC addressing mode instead of Flat Logical.
  97. You will need a new lynxer.elf file to flash your firmware with - send
  98. email to <Martin.Bligh@us.ibm.com>.
  99. config X86_SUMMIT
  100. bool "Summit/EXA (IBM x440)"
  101. depends on SMP
  102. help
  103. This option is needed for IBM systems that use the Summit/EXA chipset.
  104. In particular, it is needed for the x440.
  105. If you don't have one of these computers, you should say N here.
  106. config X86_BIGSMP
  107. bool "Support for other sub-arch SMP systems with more than 8 CPUs"
  108. depends on SMP
  109. help
  110. This option is needed for the systems that have more than 8 CPUs
  111. and if the system is not of any sub-arch type above.
  112. If you don't have such a system, you should say N here.
  113. config X86_VISWS
  114. bool "SGI 320/540 (Visual Workstation)"
  115. help
  116. The SGI Visual Workstation series is an IA32-based workstation
  117. based on SGI systems chips with some legacy PC hardware attached.
  118. Say Y here to create a kernel to run on the SGI 320 or 540.
  119. A kernel compiled for the Visual Workstation will not run on PCs
  120. and vice versa. See <file:Documentation/sgi-visws.txt> for details.
  121. config X86_GENERICARCH
  122. bool "Generic architecture (Summit, bigsmp, ES7000, default)"
  123. depends on SMP
  124. help
  125. This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
  126. It is intended for a generic binary kernel.
  127. config X86_ES7000
  128. bool "Support for Unisys ES7000 IA32 series"
  129. depends on SMP
  130. help
  131. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  132. supposed to run on an IA32-based Unisys ES7000 system.
  133. Only choose this option if you have such a system, otherwise you
  134. should say N here.
  135. endchoice
  136. config ACPI_SRAT
  137. bool
  138. default y
  139. depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
  140. select ACPI_NUMA
  141. config HAVE_ARCH_PARSE_SRAT
  142. bool
  143. default y
  144. depends on ACPI_SRAT
  145. config X86_SUMMIT_NUMA
  146. bool
  147. default y
  148. depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
  149. config X86_CYCLONE_TIMER
  150. bool
  151. default y
  152. depends on X86_SUMMIT || X86_GENERICARCH
  153. config ES7000_CLUSTERED_APIC
  154. bool
  155. default y
  156. depends on SMP && X86_ES7000 && MPENTIUMIII
  157. source "arch/i386/Kconfig.cpu"
  158. config HPET_TIMER
  159. bool "HPET Timer Support"
  160. help
  161. This enables the use of the HPET for the kernel's internal timer.
  162. HPET is the next generation timer replacing legacy 8254s.
  163. You can safely choose Y here. However, HPET will only be
  164. activated if the platform and the BIOS support this feature.
  165. Otherwise the 8254 will be used for timing services.
  166. Choose N to continue using the legacy 8254 timer.
  167. config HPET_EMULATE_RTC
  168. bool
  169. depends on HPET_TIMER && RTC=y
  170. default y
  171. config NR_CPUS
  172. int "Maximum number of CPUs (2-255)"
  173. range 2 255
  174. depends on SMP
  175. default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
  176. default "8"
  177. help
  178. This allows you to specify the maximum number of CPUs which this
  179. kernel will support. The maximum supported value is 255 and the
  180. minimum value which makes sense is 2.
  181. This is purely to save memory - each supported CPU adds
  182. approximately eight kilobytes to the kernel image.
  183. config SCHED_SMT
  184. bool "SMT (Hyperthreading) scheduler support"
  185. depends on X86_HT
  186. help
  187. SMT scheduler support improves the CPU scheduler's decision making
  188. when dealing with Intel Pentium 4 chips with HyperThreading at a
  189. cost of slightly increased overhead in some places. If unsure say
  190. N here.
  191. config SCHED_MC
  192. bool "Multi-core scheduler support"
  193. depends on X86_HT
  194. default y
  195. help
  196. Multi-core scheduler support improves the CPU scheduler's decision
  197. making when dealing with multi-core CPU chips at a cost of slightly
  198. increased overhead in some places. If unsure say N here.
  199. source "kernel/Kconfig.preempt"
  200. config X86_UP_APIC
  201. bool "Local APIC support on uniprocessors"
  202. depends on !SMP && !(X86_VISWS || X86_VOYAGER)
  203. help
  204. A local APIC (Advanced Programmable Interrupt Controller) is an
  205. integrated interrupt controller in the CPU. If you have a single-CPU
  206. system which has a processor with a local APIC, you can say Y here to
  207. enable and use it. If you say Y here even though your machine doesn't
  208. have a local APIC, then the kernel will still run with no slowdown at
  209. all. The local APIC supports CPU-generated self-interrupts (timer,
  210. performance counters), and the NMI watchdog which detects hard
  211. lockups.
  212. config X86_UP_IOAPIC
  213. bool "IO-APIC support on uniprocessors"
  214. depends on X86_UP_APIC
  215. help
  216. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  217. SMP-capable replacement for PC-style interrupt controllers. Most
  218. SMP systems and many recent uniprocessor systems have one.
  219. If you have a single-CPU system with an IO-APIC, you can say Y here
  220. to use it. If you say Y here even though your machine doesn't have
  221. an IO-APIC, then the kernel will still run with no slowdown at all.
  222. config X86_LOCAL_APIC
  223. bool
  224. depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER)
  225. default y
  226. config X86_IO_APIC
  227. bool
  228. depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER))
  229. default y
  230. config X86_VISWS_APIC
  231. bool
  232. depends on X86_VISWS
  233. default y
  234. config X86_MCE
  235. bool "Machine Check Exception"
  236. depends on !X86_VOYAGER
  237. ---help---
  238. Machine Check Exception support allows the processor to notify the
  239. kernel if it detects a problem (e.g. overheating, component failure).
  240. The action the kernel takes depends on the severity of the problem,
  241. ranging from a warning message on the console, to halting the machine.
  242. Your processor must be a Pentium or newer to support this - check the
  243. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  244. have a design flaw which leads to false MCE events - hence MCE is
  245. disabled on all P5 processors, unless explicitly enabled with "mce"
  246. as a boot argument. Similarly, if MCE is built in and creates a
  247. problem on some new non-standard machine, you can boot with "nomce"
  248. to disable it. MCE support simply ignores non-MCE processors like
  249. the 386 and 486, so nearly everyone can say Y here.
  250. config X86_MCE_NONFATAL
  251. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  252. depends on X86_MCE
  253. help
  254. Enabling this feature starts a timer that triggers every 5 seconds which
  255. will look at the machine check registers to see if anything happened.
  256. Non-fatal problems automatically get corrected (but still logged).
  257. Disable this if you don't want to see these messages.
  258. Seeing the messages this option prints out may be indicative of dying hardware,
  259. or out-of-spec (ie, overclocked) hardware.
  260. This option only does something on certain CPUs.
  261. (AMD Athlon/Duron and Intel Pentium 4)
  262. config X86_MCE_P4THERMAL
  263. bool "check for P4 thermal throttling interrupt."
  264. depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
  265. help
  266. Enabling this feature will cause a message to be printed when the P4
  267. enters thermal throttling.
  268. config VM86
  269. default y
  270. bool "Enable VM86 support" if EMBEDDED
  271. help
  272. This option is required by programs like DOSEMU to run 16-bit legacy
  273. code on X86 processors. It also may be needed by software like
  274. XFree86 to initialize some video cards via BIOS. Disabling this
  275. option saves about 6k.
  276. config TOSHIBA
  277. tristate "Toshiba Laptop support"
  278. ---help---
  279. This adds a driver to safely access the System Management Mode of
  280. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  281. not work on models with a Phoenix BIOS. The System Management Mode
  282. is used to set the BIOS and power saving options on Toshiba portables.
  283. For information on utilities to make use of this driver see the
  284. Toshiba Linux utilities web site at:
  285. <http://www.buzzard.org.uk/toshiba/>.
  286. Say Y if you intend to run this kernel on a Toshiba portable.
  287. Say N otherwise.
  288. config I8K
  289. tristate "Dell laptop support"
  290. ---help---
  291. This adds a driver to safely access the System Management Mode
  292. of the CPU on the Dell Inspiron 8000. The System Management Mode
  293. is used to read cpu temperature and cooling fan status and to
  294. control the fans on the I8K portables.
  295. This driver has been tested only on the Inspiron 8000 but it may
  296. also work with other Dell laptops. You can force loading on other
  297. models by passing the parameter `force=1' to the module. Use at
  298. your own risk.
  299. For information on utilities to make use of this driver see the
  300. I8K Linux utilities web site at:
  301. <http://people.debian.org/~dz/i8k/>
  302. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  303. Say N otherwise.
  304. config X86_REBOOTFIXUPS
  305. bool "Enable X86 board specific fixups for reboot"
  306. depends on X86
  307. default n
  308. ---help---
  309. This enables chipset and/or board specific fixups to be done
  310. in order to get reboot to work correctly. This is only needed on
  311. some combinations of hardware and BIOS. The symptom, for which
  312. this config is intended, is when reboot ends with a stalled/hung
  313. system.
  314. Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
  315. combination.
  316. Say Y if you want to enable the fixup. Currently, it's safe to
  317. enable this option even if you don't need it.
  318. Say N otherwise.
  319. config MICROCODE
  320. tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
  321. ---help---
  322. If you say Y here and also to "/dev file system support" in the
  323. 'File systems' section, you will be able to update the microcode on
  324. Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
  325. Pentium III, Pentium 4, Xeon etc. You will obviously need the
  326. actual microcode binary data itself which is not shipped with the
  327. Linux kernel.
  328. For latest news and information on obtaining all the required
  329. ingredients for this driver, check:
  330. <http://www.urbanmyth.org/microcode/>.
  331. To compile this driver as a module, choose M here: the
  332. module will be called microcode.
  333. config X86_MSR
  334. tristate "/dev/cpu/*/msr - Model-specific register support"
  335. help
  336. This device gives privileged processes access to the x86
  337. Model-Specific Registers (MSRs). It is a character device with
  338. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  339. MSR accesses are directed to a specific CPU on multi-processor
  340. systems.
  341. config X86_CPUID
  342. tristate "/dev/cpu/*/cpuid - CPU information support"
  343. help
  344. This device gives processes access to the x86 CPUID instruction to
  345. be executed on a specific processor. It is a character device
  346. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  347. /dev/cpu/31/cpuid.
  348. source "drivers/firmware/Kconfig"
  349. choice
  350. prompt "High Memory Support"
  351. default NOHIGHMEM
  352. config NOHIGHMEM
  353. bool "off"
  354. depends on !X86_NUMAQ
  355. ---help---
  356. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  357. However, the address space of 32-bit x86 processors is only 4
  358. Gigabytes large. That means that, if you have a large amount of
  359. physical memory, not all of it can be "permanently mapped" by the
  360. kernel. The physical memory that's not permanently mapped is called
  361. "high memory".
  362. If you are compiling a kernel which will never run on a machine with
  363. more than 1 Gigabyte total physical RAM, answer "off" here (default
  364. choice and suitable for most users). This will result in a "3GB/1GB"
  365. split: 3GB are mapped so that each process sees a 3GB virtual memory
  366. space and the remaining part of the 4GB virtual memory space is used
  367. by the kernel to permanently map as much physical memory as
  368. possible.
  369. If the machine has between 1 and 4 Gigabytes physical RAM, then
  370. answer "4GB" here.
  371. If more than 4 Gigabytes is used then answer "64GB" here. This
  372. selection turns Intel PAE (Physical Address Extension) mode on.
  373. PAE implements 3-level paging on IA32 processors. PAE is fully
  374. supported by Linux, PAE mode is implemented on all recent Intel
  375. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  376. then the kernel will not boot on CPUs that don't support PAE!
  377. The actual amount of total physical memory will either be
  378. auto detected or can be forced by using a kernel command line option
  379. such as "mem=256M". (Try "man bootparam" or see the documentation of
  380. your boot loader (lilo or loadlin) about how to pass options to the
  381. kernel at boot time.)
  382. If unsure, say "off".
  383. config HIGHMEM4G
  384. bool "4GB"
  385. depends on !X86_NUMAQ
  386. help
  387. Select this if you have a 32-bit processor and between 1 and 4
  388. gigabytes of physical RAM.
  389. config HIGHMEM64G
  390. bool "64GB"
  391. depends on X86_CMPXCHG64
  392. help
  393. Select this if you have a 32-bit processor and more than 4
  394. gigabytes of physical RAM.
  395. endchoice
  396. choice
  397. depends on EXPERIMENTAL && !X86_PAE
  398. prompt "Memory split" if EMBEDDED
  399. default VMSPLIT_3G
  400. help
  401. Select the desired split between kernel and user memory.
  402. If the address range available to the kernel is less than the
  403. physical memory installed, the remaining memory will be available
  404. as "high memory". Accessing high memory is a little more costly
  405. than low memory, as it needs to be mapped into the kernel first.
  406. Note that increasing the kernel address space limits the range
  407. available to user programs, making the address space there
  408. tighter. Selecting anything other than the default 3G/1G split
  409. will also likely make your kernel incompatible with binary-only
  410. kernel modules.
  411. If you are not absolutely sure what you are doing, leave this
  412. option alone!
  413. config VMSPLIT_3G
  414. bool "3G/1G user/kernel split"
  415. config VMSPLIT_3G_OPT
  416. bool "3G/1G user/kernel split (for full 1G low memory)"
  417. config VMSPLIT_2G
  418. bool "2G/2G user/kernel split"
  419. config VMSPLIT_1G
  420. bool "1G/3G user/kernel split"
  421. endchoice
  422. config PAGE_OFFSET
  423. hex
  424. default 0xB0000000 if VMSPLIT_3G_OPT
  425. default 0x78000000 if VMSPLIT_2G
  426. default 0x40000000 if VMSPLIT_1G
  427. default 0xC0000000
  428. config HIGHMEM
  429. bool
  430. depends on HIGHMEM64G || HIGHMEM4G
  431. default y
  432. config X86_PAE
  433. bool
  434. depends on HIGHMEM64G
  435. default y
  436. select RESOURCES_64BIT
  437. # Common NUMA Features
  438. config NUMA
  439. bool "Numa Memory Allocation and Scheduler Support"
  440. depends on SMP && HIGHMEM64G && (X86_NUMAQ || X86_GENERICARCH || (X86_SUMMIT && ACPI))
  441. default n if X86_PC
  442. default y if (X86_NUMAQ || X86_SUMMIT)
  443. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  444. depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  445. config NODES_SHIFT
  446. int
  447. default "4" if X86_NUMAQ
  448. default "3"
  449. depends on NEED_MULTIPLE_NODES
  450. config HAVE_ARCH_BOOTMEM_NODE
  451. bool
  452. depends on NUMA
  453. default y
  454. config ARCH_HAVE_MEMORY_PRESENT
  455. bool
  456. depends on DISCONTIGMEM
  457. default y
  458. config NEED_NODE_MEMMAP_SIZE
  459. bool
  460. depends on DISCONTIGMEM || SPARSEMEM
  461. default y
  462. config HAVE_ARCH_ALLOC_REMAP
  463. bool
  464. depends on NUMA
  465. default y
  466. config ARCH_FLATMEM_ENABLE
  467. def_bool y
  468. depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
  469. config ARCH_DISCONTIGMEM_ENABLE
  470. def_bool y
  471. depends on NUMA
  472. config ARCH_DISCONTIGMEM_DEFAULT
  473. def_bool y
  474. depends on NUMA
  475. config ARCH_SPARSEMEM_ENABLE
  476. def_bool y
  477. depends on (NUMA || (X86_PC && EXPERIMENTAL))
  478. select SPARSEMEM_STATIC
  479. config ARCH_SELECT_MEMORY_MODEL
  480. def_bool y
  481. depends on ARCH_SPARSEMEM_ENABLE
  482. source "mm/Kconfig"
  483. config HAVE_ARCH_EARLY_PFN_TO_NID
  484. bool
  485. default y
  486. depends on NUMA
  487. config HIGHPTE
  488. bool "Allocate 3rd-level pagetables from highmem"
  489. depends on HIGHMEM4G || HIGHMEM64G
  490. help
  491. The VM uses one page table entry for each page of physical memory.
  492. For systems with a lot of RAM, this can be wasteful of precious
  493. low memory. Setting this option will put user-space page table
  494. entries in high memory.
  495. config MATH_EMULATION
  496. bool "Math emulation"
  497. ---help---
  498. Linux can emulate a math coprocessor (used for floating point
  499. operations) if you don't have one. 486DX and Pentium processors have
  500. a math coprocessor built in, 486SX and 386 do not, unless you added
  501. a 487DX or 387, respectively. (The messages during boot time can
  502. give you some hints here ["man dmesg"].) Everyone needs either a
  503. coprocessor or this emulation.
  504. If you don't have a math coprocessor, you need to say Y here; if you
  505. say Y here even though you have a coprocessor, the coprocessor will
  506. be used nevertheless. (This behavior can be changed with the kernel
  507. command line option "no387", which comes handy if your coprocessor
  508. is broken. Try "man bootparam" or see the documentation of your boot
  509. loader (lilo or loadlin) about how to pass options to the kernel at
  510. boot time.) This means that it is a good idea to say Y here if you
  511. intend to use this kernel on different machines.
  512. More information about the internals of the Linux math coprocessor
  513. emulation can be found in <file:arch/i386/math-emu/README>.
  514. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  515. kernel, it won't hurt.
  516. config MTRR
  517. bool "MTRR (Memory Type Range Register) support"
  518. ---help---
  519. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  520. the Memory Type Range Registers (MTRRs) may be used to control
  521. processor access to memory ranges. This is most useful if you have
  522. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  523. allows bus write transfers to be combined into a larger transfer
  524. before bursting over the PCI/AGP bus. This can increase performance
  525. of image write operations 2.5 times or more. Saying Y here creates a
  526. /proc/mtrr file which may be used to manipulate your processor's
  527. MTRRs. Typically the X server should use this.
  528. This code has a reasonably generic interface so that similar
  529. control registers on other processors can be easily supported
  530. as well:
  531. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  532. Registers (ARRs) which provide a similar functionality to MTRRs. For
  533. these, the ARRs are used to emulate the MTRRs.
  534. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  535. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  536. write-combining. All of these processors are supported by this code
  537. and it makes sense to say Y here if you have one of them.
  538. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  539. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  540. can lead to all sorts of problems, so it's good to say Y here.
  541. You can safely say Y even if your machine doesn't have MTRRs, you'll
  542. just add about 9 KB to your kernel.
  543. See <file:Documentation/mtrr.txt> for more information.
  544. config EFI
  545. bool "Boot from EFI support (EXPERIMENTAL)"
  546. depends on ACPI
  547. default n
  548. ---help---
  549. This enables the the kernel to boot on EFI platforms using
  550. system configuration information passed to it from the firmware.
  551. This also enables the kernel to use any EFI runtime services that are
  552. available (such as the EFI variable services).
  553. This option is only useful on systems that have EFI firmware
  554. and will result in a kernel image that is ~8k larger. In addition,
  555. you must use the latest ELILO loader available at
  556. <http://elilo.sourceforge.net> in order to take advantage of
  557. kernel initialization using EFI information (neither GRUB nor LILO know
  558. anything about EFI). However, even with this option, the resultant
  559. kernel should continue to boot on existing non-EFI platforms.
  560. config IRQBALANCE
  561. bool "Enable kernel irq balancing"
  562. depends on SMP && X86_IO_APIC
  563. default y
  564. help
  565. The default yes will allow the kernel to do irq load balancing.
  566. Saying no will keep the kernel from doing irq load balancing.
  567. # turning this on wastes a bunch of space.
  568. # Summit needs it only when NUMA is on
  569. config BOOT_IOREMAP
  570. bool
  571. depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
  572. default y
  573. config REGPARM
  574. bool "Use register arguments"
  575. default y
  576. help
  577. Compile the kernel with -mregparm=3. This instructs gcc to use
  578. a more efficient function call ABI which passes the first three
  579. arguments of a function call via registers, which results in denser
  580. and faster code.
  581. If this option is disabled, then the default ABI of passing
  582. arguments via the stack is used.
  583. If unsure, say Y.
  584. config SECCOMP
  585. bool "Enable seccomp to safely compute untrusted bytecode"
  586. depends on PROC_FS
  587. default y
  588. help
  589. This kernel feature is useful for number crunching applications
  590. that may need to compute untrusted bytecode during their
  591. execution. By using pipes or other transports made available to
  592. the process as file descriptors supporting the read/write
  593. syscalls, it's possible to isolate those applications in
  594. their own address space using seccomp. Once seccomp is
  595. enabled via /proc/<pid>/seccomp, it cannot be disabled
  596. and the task is only allowed to execute a few safe syscalls
  597. defined by each seccomp mode.
  598. If unsure, say Y. Only embedded should say N here.
  599. source kernel/Kconfig.hz
  600. config KEXEC
  601. bool "kexec system call (EXPERIMENTAL)"
  602. depends on EXPERIMENTAL
  603. help
  604. kexec is a system call that implements the ability to shutdown your
  605. current kernel, and to start another kernel. It is like a reboot
  606. but it is independent of the system firmware. And like a reboot
  607. you can start any kernel with it, not just Linux.
  608. The name comes from the similarity to the exec system call.
  609. It is an ongoing process to be certain the hardware in a machine
  610. is properly shutdown, so do not be surprised if this code does not
  611. initially work for you. It may help to enable device hotplugging
  612. support. As of this writing the exact hardware interface is
  613. strongly in flux, so no good recommendation can be made.
  614. config CRASH_DUMP
  615. bool "kernel crash dumps (EXPERIMENTAL)"
  616. depends on EXPERIMENTAL
  617. depends on HIGHMEM
  618. help
  619. Generate crash dump after being started by kexec.
  620. config PHYSICAL_START
  621. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  622. default "0x1000000" if CRASH_DUMP
  623. default "0x100000"
  624. help
  625. This gives the physical address where the kernel is loaded. Normally
  626. for regular kernels this value is 0x100000 (1MB). But in the case
  627. of kexec on panic the fail safe kernel needs to run at a different
  628. address than the panic-ed kernel. This option is used to set the load
  629. address for kernels used to capture crash dump on being kexec'ed
  630. after panic. The default value for crash dump kernels is
  631. 0x1000000 (16MB). This can also be set based on the "X" value as
  632. specified in the "crashkernel=YM@XM" command line boot parameter
  633. passed to the panic-ed kernel. Typically this parameter is set as
  634. crashkernel=64M@16M. Please take a look at
  635. Documentation/kdump/kdump.txt for more details about crash dumps.
  636. Don't change this unless you know what you are doing.
  637. config HOTPLUG_CPU
  638. bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
  639. depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
  640. ---help---
  641. Say Y here to experiment with turning CPUs off and on, and to
  642. enable suspend on SMP systems. CPUs can be controlled through
  643. /sys/devices/system/cpu.
  644. config COMPAT_VDSO
  645. bool "Compat VDSO support"
  646. default y
  647. help
  648. Map the VDSO to the predictable old-style address too.
  649. ---help---
  650. Say N here if you are running a sufficiently recent glibc
  651. version (2.3.3 or later), to remove the high-mapped
  652. VDSO mapping and to exclusively use the randomized VDSO.
  653. If unsure, say Y.
  654. endmenu
  655. config ARCH_ENABLE_MEMORY_HOTPLUG
  656. def_bool y
  657. depends on HIGHMEM
  658. menu "Power management options (ACPI, APM)"
  659. depends on !X86_VOYAGER
  660. source kernel/power/Kconfig
  661. source "drivers/acpi/Kconfig"
  662. menu "APM (Advanced Power Management) BIOS Support"
  663. depends on PM && !X86_VISWS
  664. config APM
  665. tristate "APM (Advanced Power Management) BIOS support"
  666. depends on PM
  667. ---help---
  668. APM is a BIOS specification for saving power using several different
  669. techniques. This is mostly useful for battery powered laptops with
  670. APM compliant BIOSes. If you say Y here, the system time will be
  671. reset after a RESUME operation, the /proc/apm device will provide
  672. battery status information, and user-space programs will receive
  673. notification of APM "events" (e.g. battery status change).
  674. If you select "Y" here, you can disable actual use of the APM
  675. BIOS by passing the "apm=off" option to the kernel at boot time.
  676. Note that the APM support is almost completely disabled for
  677. machines with more than one CPU.
  678. In order to use APM, you will need supporting software. For location
  679. and more information, read <file:Documentation/pm.txt> and the
  680. Battery Powered Linux mini-HOWTO, available from
  681. <http://www.tldp.org/docs.html#howto>.
  682. This driver does not spin down disk drives (see the hdparm(8)
  683. manpage ("man 8 hdparm") for that), and it doesn't turn off
  684. VESA-compliant "green" monitors.
  685. This driver does not support the TI 4000M TravelMate and the ACER
  686. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  687. desktop machines also don't have compliant BIOSes, and this driver
  688. may cause those machines to panic during the boot phase.
  689. Generally, if you don't have a battery in your machine, there isn't
  690. much point in using this driver and you should say N. If you get
  691. random kernel OOPSes or reboots that don't seem to be related to
  692. anything, try disabling/enabling this option (or disabling/enabling
  693. APM in your BIOS).
  694. Some other things you should try when experiencing seemingly random,
  695. "weird" problems:
  696. 1) make sure that you have enough swap space and that it is
  697. enabled.
  698. 2) pass the "no-hlt" option to the kernel
  699. 3) switch on floating point emulation in the kernel and pass
  700. the "no387" option to the kernel
  701. 4) pass the "floppy=nodma" option to the kernel
  702. 5) pass the "mem=4M" option to the kernel (thereby disabling
  703. all but the first 4 MB of RAM)
  704. 6) make sure that the CPU is not over clocked.
  705. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  706. 8) disable the cache from your BIOS settings
  707. 9) install a fan for the video card or exchange video RAM
  708. 10) install a better fan for the CPU
  709. 11) exchange RAM chips
  710. 12) exchange the motherboard.
  711. To compile this driver as a module, choose M here: the
  712. module will be called apm.
  713. config APM_IGNORE_USER_SUSPEND
  714. bool "Ignore USER SUSPEND"
  715. depends on APM
  716. help
  717. This option will ignore USER SUSPEND requests. On machines with a
  718. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  719. series notebooks, it is necessary to say Y because of a BIOS bug.
  720. config APM_DO_ENABLE
  721. bool "Enable PM at boot time"
  722. depends on APM
  723. ---help---
  724. Enable APM features at boot time. From page 36 of the APM BIOS
  725. specification: "When disabled, the APM BIOS does not automatically
  726. power manage devices, enter the Standby State, enter the Suspend
  727. State, or take power saving steps in response to CPU Idle calls."
  728. This driver will make CPU Idle calls when Linux is idle (unless this
  729. feature is turned off -- see "Do CPU IDLE calls", below). This
  730. should always save battery power, but more complicated APM features
  731. will be dependent on your BIOS implementation. You may need to turn
  732. this option off if your computer hangs at boot time when using APM
  733. support, or if it beeps continuously instead of suspending. Turn
  734. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  735. T400CDT. This is off by default since most machines do fine without
  736. this feature.
  737. config APM_CPU_IDLE
  738. bool "Make CPU Idle calls when idle"
  739. depends on APM
  740. help
  741. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  742. On some machines, this can activate improved power savings, such as
  743. a slowed CPU clock rate, when the machine is idle. These idle calls
  744. are made after the idle loop has run for some length of time (e.g.,
  745. 333 mS). On some machines, this will cause a hang at boot time or
  746. whenever the CPU becomes idle. (On machines with more than one CPU,
  747. this option does nothing.)
  748. config APM_DISPLAY_BLANK
  749. bool "Enable console blanking using APM"
  750. depends on APM
  751. help
  752. Enable console blanking using the APM. Some laptops can use this to
  753. turn off the LCD backlight when the screen blanker of the Linux
  754. virtual console blanks the screen. Note that this is only used by
  755. the virtual console screen blanker, and won't turn off the backlight
  756. when using the X Window system. This also doesn't have anything to
  757. do with your VESA-compliant power-saving monitor. Further, this
  758. option doesn't work for all laptops -- it might not turn off your
  759. backlight at all, or it might print a lot of errors to the console,
  760. especially if you are using gpm.
  761. config APM_RTC_IS_GMT
  762. bool "RTC stores time in GMT"
  763. depends on APM
  764. help
  765. Say Y here if your RTC (Real Time Clock a.k.a. hardware clock)
  766. stores the time in GMT (Greenwich Mean Time). Say N if your RTC
  767. stores localtime.
  768. It is in fact recommended to store GMT in your RTC, because then you
  769. don't have to worry about daylight savings time changes. The only
  770. reason not to use GMT in your RTC is if you also run a broken OS
  771. that doesn't understand GMT.
  772. config APM_ALLOW_INTS
  773. bool "Allow interrupts during APM BIOS calls"
  774. depends on APM
  775. help
  776. Normally we disable external interrupts while we are making calls to
  777. the APM BIOS as a measure to lessen the effects of a badly behaving
  778. BIOS implementation. The BIOS should reenable interrupts if it
  779. needs to. Unfortunately, some BIOSes do not -- especially those in
  780. many of the newer IBM Thinkpads. If you experience hangs when you
  781. suspend, try setting this to Y. Otherwise, say N.
  782. config APM_REAL_MODE_POWER_OFF
  783. bool "Use real mode APM BIOS call to power off"
  784. depends on APM
  785. help
  786. Use real mode APM BIOS calls to switch off the computer. This is
  787. a work-around for a number of buggy BIOSes. Switch this option on if
  788. your computer crashes instead of powering off properly.
  789. endmenu
  790. source "arch/i386/kernel/cpu/cpufreq/Kconfig"
  791. endmenu
  792. menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
  793. config PCI
  794. bool "PCI support" if !X86_VISWS
  795. depends on !X86_VOYAGER
  796. default y if X86_VISWS
  797. help
  798. Find out whether you have a PCI motherboard. PCI is the name of a
  799. bus system, i.e. the way the CPU talks to the other stuff inside
  800. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  801. VESA. If you have PCI, say Y, otherwise N.
  802. The PCI-HOWTO, available from
  803. <http://www.tldp.org/docs.html#howto>, contains valuable
  804. information about which PCI hardware does work under Linux and which
  805. doesn't.
  806. choice
  807. prompt "PCI access mode"
  808. depends on PCI && !X86_VISWS
  809. default PCI_GOANY
  810. ---help---
  811. On PCI systems, the BIOS can be used to detect the PCI devices and
  812. determine their configuration. However, some old PCI motherboards
  813. have BIOS bugs and may crash if this is done. Also, some embedded
  814. PCI-based systems don't have any BIOS at all. Linux can also try to
  815. detect the PCI hardware directly without using the BIOS.
  816. With this option, you can specify how Linux should detect the
  817. PCI devices. If you choose "BIOS", the BIOS will be used,
  818. if you choose "Direct", the BIOS won't be used, and if you
  819. choose "MMConfig", then PCI Express MMCONFIG will be used.
  820. If you choose "Any", the kernel will try MMCONFIG, then the
  821. direct access method and falls back to the BIOS if that doesn't
  822. work. If unsure, go with the default, which is "Any".
  823. config PCI_GOBIOS
  824. bool "BIOS"
  825. config PCI_GOMMCONFIG
  826. bool "MMConfig"
  827. config PCI_GODIRECT
  828. bool "Direct"
  829. config PCI_GOANY
  830. bool "Any"
  831. endchoice
  832. config PCI_BIOS
  833. bool
  834. depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
  835. default y
  836. config PCI_DIRECT
  837. bool
  838. depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
  839. default y
  840. config PCI_MMCONFIG
  841. bool
  842. depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  843. default y
  844. source "drivers/pci/pcie/Kconfig"
  845. source "drivers/pci/Kconfig"
  846. config ISA_DMA_API
  847. bool
  848. default y
  849. config ISA
  850. bool "ISA support"
  851. depends on !(X86_VOYAGER || X86_VISWS)
  852. help
  853. Find out whether you have ISA slots on your motherboard. ISA is the
  854. name of a bus system, i.e. the way the CPU talks to the other stuff
  855. inside your box. Other bus systems are PCI, EISA, MicroChannel
  856. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  857. newer boards don't support it. If you have ISA, say Y, otherwise N.
  858. config EISA
  859. bool "EISA support"
  860. depends on ISA
  861. ---help---
  862. The Extended Industry Standard Architecture (EISA) bus was
  863. developed as an open alternative to the IBM MicroChannel bus.
  864. The EISA bus provided some of the features of the IBM MicroChannel
  865. bus while maintaining backward compatibility with cards made for
  866. the older ISA bus. The EISA bus saw limited use between 1988 and
  867. 1995 when it was made obsolete by the PCI bus.
  868. Say Y here if you are building a kernel for an EISA-based machine.
  869. Otherwise, say N.
  870. source "drivers/eisa/Kconfig"
  871. config MCA
  872. bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
  873. default y if X86_VOYAGER
  874. help
  875. MicroChannel Architecture is found in some IBM PS/2 machines and
  876. laptops. It is a bus system similar to PCI or ISA. See
  877. <file:Documentation/mca.txt> (and especially the web page given
  878. there) before attempting to build an MCA bus kernel.
  879. source "drivers/mca/Kconfig"
  880. config SCx200
  881. tristate "NatSemi SCx200 support"
  882. depends on !X86_VOYAGER
  883. help
  884. This provides basic support for National Semiconductor's
  885. (now AMD's) Geode processors. The driver probes for the
  886. PCI-IDs of several on-chip devices, so its a good dependency
  887. for other scx200_* drivers.
  888. If compiled as a module, the driver is named scx200.
  889. config SCx200HR_TIMER
  890. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  891. depends on SCx200 && GENERIC_TIME
  892. default y
  893. help
  894. This driver provides a clocksource built upon the on-chip
  895. 27MHz high-resolution timer. Its also a workaround for
  896. NSC Geode SC-1100's buggy TSC, which loses time when the
  897. processor goes idle (as is done by the scheduler). The
  898. other workaround is idle=poll boot option.
  899. config K8_NB
  900. def_bool y
  901. depends on AGP_AMD64
  902. source "drivers/pcmcia/Kconfig"
  903. source "drivers/pci/hotplug/Kconfig"
  904. endmenu
  905. menu "Executable file formats"
  906. source "fs/Kconfig.binfmt"
  907. endmenu
  908. source "net/Kconfig"
  909. source "drivers/Kconfig"
  910. source "fs/Kconfig"
  911. menu "Instrumentation Support"
  912. depends on EXPERIMENTAL
  913. source "arch/i386/oprofile/Kconfig"
  914. config KPROBES
  915. bool "Kprobes (EXPERIMENTAL)"
  916. depends on EXPERIMENTAL && MODULES
  917. help
  918. Kprobes allows you to trap at almost any kernel address and
  919. execute a callback function. register_kprobe() establishes
  920. a probepoint and specifies the callback. Kprobes is useful
  921. for kernel debugging, non-intrusive instrumentation and testing.
  922. If in doubt, say "N".
  923. endmenu
  924. source "arch/i386/Kconfig.debug"
  925. source "security/Kconfig"
  926. source "crypto/Kconfig"
  927. source "lib/Kconfig"
  928. #
  929. # Use the generic interrupt handling code in kernel/irq/:
  930. #
  931. config GENERIC_HARDIRQS
  932. bool
  933. default y
  934. config GENERIC_IRQ_PROBE
  935. bool
  936. default y
  937. config GENERIC_PENDING_IRQ
  938. bool
  939. depends on GENERIC_HARDIRQS && SMP
  940. default y
  941. config X86_SMP
  942. bool
  943. depends on SMP && !X86_VOYAGER
  944. default y
  945. config X86_HT
  946. bool
  947. depends on SMP && !(X86_VISWS || X86_VOYAGER)
  948. default y
  949. config X86_BIOS_REBOOT
  950. bool
  951. depends on !(X86_VISWS || X86_VOYAGER)
  952. default y
  953. config X86_TRAMPOLINE
  954. bool
  955. depends on X86_SMP || (X86_VOYAGER && SMP)
  956. default y
  957. config KTIME_SCALAR
  958. bool
  959. default y