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