| blob | f41c9538ca303f2fdb5b231cc9c9592b72024e23 |
1 # x86 configuration
2 mainmenu "Linux Kernel Configuration for x86"
4 # Select 32 or 64 bit
5 config 64BIT
6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
8 help
9 Say yes to build a 64-bit kernel - formerly known as x86_64
10 Say no to build a 32-bit kernel - formerly known as i386
12 config X86_32
13 def_bool !64BIT
15 config X86_64
16 def_bool 64BIT
18 ### Arch settings
19 config X86
20 def_bool y
21 select HAVE_IDE
22 select HAVE_OPROFILE
23 select HAVE_KPROBES
24 select HAVE_KRETPROBES
25 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
28 config GENERIC_LOCKBREAK
29 def_bool n
31 config GENERIC_TIME
32 def_bool y
34 config GENERIC_CMOS_UPDATE
35 def_bool y
37 config CLOCKSOURCE_WATCHDOG
38 def_bool y
40 config GENERIC_CLOCKEVENTS
41 def_bool y
43 config GENERIC_CLOCKEVENTS_BROADCAST
44 def_bool y
45 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
47 config LOCKDEP_SUPPORT
48 def_bool y
50 config STACKTRACE_SUPPORT
51 def_bool y
53 config HAVE_LATENCYTOP_SUPPORT
54 def_bool y
56 config SEMAPHORE_SLEEPERS
57 def_bool y
59 config FAST_CMPXCHG_LOCAL
60 bool
61 default y
63 config MMU
64 def_bool y
66 config ZONE_DMA
67 def_bool y
69 config QUICKLIST
70 def_bool X86_32
72 config SBUS
73 bool
75 config GENERIC_ISA_DMA
76 def_bool y
78 config GENERIC_IOMAP
79 def_bool y
81 config GENERIC_BUG
82 def_bool y
83 depends on BUG
85 config GENERIC_HWEIGHT
86 def_bool y
88 config GENERIC_GPIO
89 def_bool n
91 config ARCH_MAY_HAVE_PC_FDC
92 def_bool y
94 config DMI
95 def_bool y
97 config RWSEM_GENERIC_SPINLOCK
98 def_bool !X86_XADD
100 config RWSEM_XCHGADD_ALGORITHM
101 def_bool X86_XADD
103 config ARCH_HAS_ILOG2_U32
104 def_bool n
106 config ARCH_HAS_ILOG2_U64
107 def_bool n
109 config ARCH_HAS_CPU_IDLE_WAIT
110 def_bool y
112 config GENERIC_CALIBRATE_DELAY
113 def_bool y
115 config GENERIC_TIME_VSYSCALL
116 bool
117 default X86_64
119 config ARCH_HAS_CPU_RELAX
120 def_bool y
122 config HAVE_SETUP_PER_CPU_AREA
123 def_bool X86_64
125 config ARCH_HIBERNATION_POSSIBLE
126 def_bool y
127 depends on !SMP || !X86_VOYAGER
129 config ARCH_SUSPEND_POSSIBLE
130 def_bool y
131 depends on !X86_VOYAGER
133 config ZONE_DMA32
134 bool
135 default X86_64
137 config ARCH_POPULATES_NODE_MAP
138 def_bool y
140 config AUDIT_ARCH
141 bool
142 default X86_64
144 config ARCH_SUPPORTS_AOUT
145 def_bool y
147 # Use the generic interrupt handling code in kernel/irq/:
148 config GENERIC_HARDIRQS
149 bool
150 default y
152 config GENERIC_IRQ_PROBE
153 bool
154 default y
156 config GENERIC_PENDING_IRQ
157 bool
158 depends on GENERIC_HARDIRQS && SMP
159 default y
161 config X86_SMP
162 bool
163 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
164 default y
166 config X86_32_SMP
167 def_bool y
168 depends on X86_32 && SMP
170 config X86_64_SMP
171 def_bool y
172 depends on X86_64 && SMP
174 config X86_HT
175 bool
176 depends on SMP
177 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || (X86_64 && !MK8)
178 default y
180 config X86_BIOS_REBOOT
181 bool
182 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
183 default y
185 config X86_TRAMPOLINE
186 bool
187 depends on X86_SMP || (X86_VOYAGER && SMP)
188 default y
190 config KTIME_SCALAR
191 def_bool X86_32
192 source "init/Kconfig"
194 menu "Processor type and features"
196 source "kernel/time/Kconfig"
198 config SMP
199 bool "Symmetric multi-processing support"
200 ---help---
201 This enables support for systems with more than one CPU. If you have
202 a system with only one CPU, like most personal computers, say N. If
203 you have a system with more than one CPU, say Y.
205 If you say N here, the kernel will run on single and multiprocessor
206 machines, but will use only one CPU of a multiprocessor machine. If
207 you say Y here, the kernel will run on many, but not all,
208 singleprocessor machines. On a singleprocessor machine, the kernel
209 will run faster if you say N here.
211 Note that if you say Y here and choose architecture "586" or
212 "Pentium" under "Processor family", the kernel will not work on 486
213 architectures. Similarly, multiprocessor kernels for the "PPro"
214 architecture may not work on all Pentium based boards.
216 People using multiprocessor machines who say Y here should also say
217 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
218 Management" code will be disabled if you say Y here.
220 See also <file:Documentation/i386/IO-APIC.txt>,
221 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
222 <http://www.tldp.org/docs.html#howto>.
224 If you don't know what to do here, say N.
226 choice
227 prompt "Subarchitecture Type"
228 default X86_PC
230 config X86_PC
231 bool "PC-compatible"
232 help
233 Choose this option if your computer is a standard PC or compatible.
235 config X86_ELAN
236 bool "AMD Elan"
237 depends on X86_32
238 help
239 Select this for an AMD Elan processor.
241 Do not use this option for K6/Athlon/Opteron processors!
243 If unsure, choose "PC-compatible" instead.
245 config X86_VOYAGER
246 bool "Voyager (NCR)"
247 depends on X86_32
248 select SMP if !BROKEN
249 help
250 Voyager is an MCA-based 32-way capable SMP architecture proprietary
251 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
253 *** WARNING ***
255 If you do not specifically know you have a Voyager based machine,
256 say N here, otherwise the kernel you build will not be bootable.
258 config X86_NUMAQ
259 bool "NUMAQ (IBM/Sequent)"
260 select SMP
261 select NUMA
262 depends on X86_32
263 help
264 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
265 multiquad box. This changes the way that processors are bootstrapped,
266 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
267 You will need a new lynxer.elf file to flash your firmware with - send
268 email to <Martin.Bligh@us.ibm.com>.
270 config X86_SUMMIT
271 bool "Summit/EXA (IBM x440)"
272 depends on X86_32 && SMP
273 help
274 This option is needed for IBM systems that use the Summit/EXA chipset.
275 In particular, it is needed for the x440.
277 If you don't have one of these computers, you should say N here.
278 If you want to build a NUMA kernel, you must select ACPI.
280 config X86_BIGSMP
281 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
282 depends on X86_32 && SMP
283 help
284 This option is needed for the systems that have more than 8 CPUs
285 and if the system is not of any sub-arch type above.
287 If you don't have such a system, you should say N here.
289 config X86_VISWS
290 bool "SGI 320/540 (Visual Workstation)"
291 depends on X86_32
292 help
293 The SGI Visual Workstation series is an IA32-based workstation
294 based on SGI systems chips with some legacy PC hardware attached.
296 Say Y here to create a kernel to run on the SGI 320 or 540.
298 A kernel compiled for the Visual Workstation will not run on PCs
299 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
301 config X86_GENERICARCH
302 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
303 depends on X86_32
304 help
305 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
306 It is intended for a generic binary kernel.
307 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
309 config X86_ES7000
310 bool "Support for Unisys ES7000 IA32 series"
311 depends on X86_32 && SMP
312 help
313 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
314 supposed to run on an IA32-based Unisys ES7000 system.
315 Only choose this option if you have such a system, otherwise you
316 should say N here.
318 config X86_RDC321X
319 bool "RDC R-321x SoC"
320 depends on X86_32
321 select M486
322 select X86_REBOOTFIXUPS
323 select GENERIC_GPIO
324 select LEDS_CLASS
325 select LEDS_GPIO
326 help
327 This option is needed for RDC R-321x system-on-chip, also known
328 as R-8610-(G).
329 If you don't have one of these chips, you should say N here.
331 config X86_VSMP
332 bool "Support for ScaleMP vSMP"
333 depends on X86_64 && PCI
334 help
335 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
336 supposed to run on these EM64T-based machines. Only choose this option
337 if you have one of these machines.
339 endchoice
341 config SCHED_NO_NO_OMIT_FRAME_POINTER
342 def_bool y
343 prompt "Single-depth WCHAN output"
344 depends on X86_32
345 help
346 Calculate simpler /proc/<PID>/wchan values. If this option
347 is disabled then wchan values will recurse back to the
348 caller function. This provides more accurate wchan values,
349 at the expense of slightly more scheduling overhead.
351 If in doubt, say "Y".
353 menuconfig PARAVIRT_GUEST
354 bool "Paravirtualized guest support"
355 help
356 Say Y here to get to see options related to running Linux under
357 various hypervisors. This option alone does not add any kernel code.
359 If you say N, all options in this submenu will be skipped and disabled.
361 if PARAVIRT_GUEST
363 source "arch/x86/xen/Kconfig"
365 config VMI
366 bool "VMI Guest support"
367 select PARAVIRT
368 depends on X86_32
369 depends on !(X86_VISWS || X86_VOYAGER)
370 help
371 VMI provides a paravirtualized interface to the VMware ESX server
372 (it could be used by other hypervisors in theory too, but is not
373 at the moment), by linking the kernel to a GPL-ed ROM module
374 provided by the hypervisor.
376 source "arch/x86/lguest/Kconfig"
378 config PARAVIRT
379 bool "Enable paravirtualization code"
380 depends on !(X86_VISWS || X86_VOYAGER)
381 help
382 This changes the kernel so it can modify itself when it is run
383 under a hypervisor, potentially improving performance significantly
384 over full virtualization. However, when run without a hypervisor
385 the kernel is theoretically slower and slightly larger.
387 endif
389 config ACPI_SRAT
390 def_bool y
391 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
392 select ACPI_NUMA
394 config HAVE_ARCH_PARSE_SRAT
395 def_bool y
396 depends on ACPI_SRAT
398 config X86_SUMMIT_NUMA
399 def_bool y
400 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
402 config X86_CYCLONE_TIMER
403 def_bool y
404 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
406 config ES7000_CLUSTERED_APIC
407 def_bool y
408 depends on SMP && X86_ES7000 && MPENTIUMIII
410 source "arch/x86/Kconfig.cpu"
412 config HPET_TIMER
413 def_bool X86_64
414 prompt "HPET Timer Support" if X86_32
415 help
416 Use the IA-PC HPET (High Precision Event Timer) to manage
417 time in preference to the PIT and RTC, if a HPET is
418 present.
419 HPET is the next generation timer replacing legacy 8254s.
420 The HPET provides a stable time base on SMP
421 systems, unlike the TSC, but it is more expensive to access,
422 as it is off-chip. You can find the HPET spec at
423 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
425 You can safely choose Y here. However, HPET will only be
426 activated if the platform and the BIOS support this feature.
427 Otherwise the 8254 will be used for timing services.
429 Choose N to continue using the legacy 8254 timer.
431 config HPET_EMULATE_RTC
432 def_bool y
433 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
435 # Mark as embedded because too many people got it wrong.
436 # The code disables itself when not needed.
437 config GART_IOMMU
438 bool "GART IOMMU support" if EMBEDDED
439 default y
440 select SWIOTLB
441 select AGP
442 depends on X86_64 && PCI
443 help
444 Support for full DMA access of devices with 32bit memory access only
445 on systems with more than 3GB. This is usually needed for USB,
446 sound, many IDE/SATA chipsets and some other devices.
447 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
448 based hardware IOMMU and a software bounce buffer based IOMMU used
449 on Intel systems and as fallback.
450 The code is only active when needed (enough memory and limited
451 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
452 too.
454 config CALGARY_IOMMU
455 bool "IBM Calgary IOMMU support"
456 select SWIOTLB
457 depends on X86_64 && PCI && EXPERIMENTAL
458 help
459 Support for hardware IOMMUs in IBM's xSeries x366 and x460
460 systems. Needed to run systems with more than 3GB of memory
461 properly with 32-bit PCI devices that do not support DAC
462 (Double Address Cycle). Calgary also supports bus level
463 isolation, where all DMAs pass through the IOMMU. This
464 prevents them from going anywhere except their intended
465 destination. This catches hard-to-find kernel bugs and
466 mis-behaving drivers and devices that do not use the DMA-API
467 properly to set up their DMA buffers. The IOMMU can be
468 turned off at boot time with the iommu=off parameter.
469 Normally the kernel will make the right choice by itself.
470 If unsure, say Y.
472 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
473 def_bool y
474 prompt "Should Calgary be enabled by default?"
475 depends on CALGARY_IOMMU
476 help
477 Should Calgary be enabled by default? if you choose 'y', Calgary
478 will be used (if it exists). If you choose 'n', Calgary will not be
479 used even if it exists. If you choose 'n' and would like to use
480 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
481 If unsure, say Y.
483 config IOMMU_HELPER
484 def_bool (CALGARY_IOMMU || GART_IOMMU)
486 # need this always selected by IOMMU for the VIA workaround
487 config SWIOTLB
488 bool
489 help
490 Support for software bounce buffers used on x86-64 systems
491 which don't have a hardware IOMMU (e.g. the current generation
492 of Intel's x86-64 CPUs). Using this PCI devices which can only
493 access 32-bits of memory can be used on systems with more than
494 3 GB of memory. If unsure, say Y.
497 config NR_CPUS
498 int "Maximum number of CPUs (2-255)"
499 range 2 255
500 depends on SMP
501 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
502 default "8"
503 help
504 This allows you to specify the maximum number of CPUs which this
505 kernel will support. The maximum supported value is 255 and the
506 minimum value which makes sense is 2.
508 This is purely to save memory - each supported CPU adds
509 approximately eight kilobytes to the kernel image.
511 config SCHED_SMT
512 bool "SMT (Hyperthreading) scheduler support"
513 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
514 help
515 SMT scheduler support improves the CPU scheduler's decision making
516 when dealing with Intel Pentium 4 chips with HyperThreading at a
517 cost of slightly increased overhead in some places. If unsure say
518 N here.
520 config SCHED_MC
521 def_bool y
522 prompt "Multi-core scheduler support"
523 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
524 help
525 Multi-core scheduler support improves the CPU scheduler's decision
526 making when dealing with multi-core CPU chips at a cost of slightly
527 increased overhead in some places. If unsure say N here.
529 source "kernel/Kconfig.preempt"
531 config X86_UP_APIC
532 bool "Local APIC support on uniprocessors"
533 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
534 help
535 A local APIC (Advanced Programmable Interrupt Controller) is an
536 integrated interrupt controller in the CPU. If you have a single-CPU
537 system which has a processor with a local APIC, you can say Y here to
538 enable and use it. If you say Y here even though your machine doesn't
539 have a local APIC, then the kernel will still run with no slowdown at
540 all. The local APIC supports CPU-generated self-interrupts (timer,
541 performance counters), and the NMI watchdog which detects hard
542 lockups.
544 config X86_UP_IOAPIC
545 bool "IO-APIC support on uniprocessors"
546 depends on X86_UP_APIC
547 help
548 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
549 SMP-capable replacement for PC-style interrupt controllers. Most
550 SMP systems and many recent uniprocessor systems have one.
552 If you have a single-CPU system with an IO-APIC, you can say Y here
553 to use it. If you say Y here even though your machine doesn't have
554 an IO-APIC, then the kernel will still run with no slowdown at all.
556 config X86_LOCAL_APIC
557 def_bool y
558 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
560 config X86_IO_APIC
561 def_bool y
562 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
564 config X86_VISWS_APIC
565 def_bool y
566 depends on X86_32 && X86_VISWS
568 config X86_MCE
569 bool "Machine Check Exception"
570 depends on !X86_VOYAGER
571 ---help---
572 Machine Check Exception support allows the processor to notify the
573 kernel if it detects a problem (e.g. overheating, component failure).
574 The action the kernel takes depends on the severity of the problem,
575 ranging from a warning message on the console, to halting the machine.
576 Your processor must be a Pentium or newer to support this - check the
577 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
578 have a design flaw which leads to false MCE events - hence MCE is
579 disabled on all P5 processors, unless explicitly enabled with "mce"
580 as a boot argument. Similarly, if MCE is built in and creates a
581 problem on some new non-standard machine, you can boot with "nomce"
582 to disable it. MCE support simply ignores non-MCE processors like
583 the 386 and 486, so nearly everyone can say Y here.
585 config X86_MCE_INTEL
586 def_bool y
587 prompt "Intel MCE features"
588 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
589 help
590 Additional support for intel specific MCE features such as
591 the thermal monitor.
593 config X86_MCE_AMD
594 def_bool y
595 prompt "AMD MCE features"
596 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
597 help
598 Additional support for AMD specific MCE features such as
599 the DRAM Error Threshold.
601 config X86_MCE_NONFATAL
602 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
603 depends on X86_32 && X86_MCE
604 help
605 Enabling this feature starts a timer that triggers every 5 seconds which
606 will look at the machine check registers to see if anything happened.
607 Non-fatal problems automatically get corrected (but still logged).
608 Disable this if you don't want to see these messages.
609 Seeing the messages this option prints out may be indicative of dying
610 or out-of-spec (ie, overclocked) hardware.
611 This option only does something on certain CPUs.
612 (AMD Athlon/Duron and Intel Pentium 4)
614 config X86_MCE_P4THERMAL
615 bool "check for P4 thermal throttling interrupt."
616 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
617 help
618 Enabling this feature will cause a message to be printed when the P4
619 enters thermal throttling.
621 config VM86
622 bool "Enable VM86 support" if EMBEDDED
623 default y
624 depends on X86_32
625 help
626 This option is required by programs like DOSEMU to run 16-bit legacy
627 code on X86 processors. It also may be needed by software like
628 XFree86 to initialize some video cards via BIOS. Disabling this
629 option saves about 6k.
631 config TOSHIBA
632 tristate "Toshiba Laptop support"
633 depends on X86_32
634 ---help---
635 This adds a driver to safely access the System Management Mode of
636 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
637 not work on models with a Phoenix BIOS. The System Management Mode
638 is used to set the BIOS and power saving options on Toshiba portables.
640 For information on utilities to make use of this driver see the
641 Toshiba Linux utilities web site at:
642 <http://www.buzzard.org.uk/toshiba/>.
644 Say Y if you intend to run this kernel on a Toshiba portable.
645 Say N otherwise.
647 config I8K
648 tristate "Dell laptop support"
649 ---help---
650 This adds a driver to safely access the System Management Mode
651 of the CPU on the Dell Inspiron 8000. The System Management Mode
652 is used to read cpu temperature and cooling fan status and to
653 control the fans on the I8K portables.
655 This driver has been tested only on the Inspiron 8000 but it may
656 also work with other Dell laptops. You can force loading on other
657 models by passing the parameter `force=1' to the module. Use at
658 your own risk.
660 For information on utilities to make use of this driver see the
661 I8K Linux utilities web site at:
662 <http://people.debian.org/~dz/i8k/>
664 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
665 Say N otherwise.
667 config X86_REBOOTFIXUPS
668 def_bool n
669 prompt "Enable X86 board specific fixups for reboot"
670 depends on X86_32 && X86
671 ---help---
672 This enables chipset and/or board specific fixups to be done
673 in order to get reboot to work correctly. This is only needed on
674 some combinations of hardware and BIOS. The symptom, for which
675 this config is intended, is when reboot ends with a stalled/hung
676 system.
678 Currently, the only fixup is for the Geode machines using
679 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
681 Say Y if you want to enable the fixup. Currently, it's safe to
682 enable this option even if you don't need it.
683 Say N otherwise.
685 config MICROCODE
686 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
687 select FW_LOADER
688 ---help---
689 If you say Y here, you will be able to update the microcode on
690 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
691 Pentium III, Pentium 4, Xeon etc. You will obviously need the
692 actual microcode binary data itself which is not shipped with the
693 Linux kernel.
695 For latest news and information on obtaining all the required
696 ingredients for this driver, check:
697 <http://www.urbanmyth.org/microcode/>.
699 To compile this driver as a module, choose M here: the
700 module will be called microcode.
702 config MICROCODE_OLD_INTERFACE
703 def_bool y
704 depends on MICROCODE
706 config X86_MSR
707 tristate "/dev/cpu/*/msr - Model-specific register support"
708 help
709 This device gives privileged processes access to the x86
710 Model-Specific Registers (MSRs). It is a character device with
711 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
712 MSR accesses are directed to a specific CPU on multi-processor
713 systems.
715 config X86_CPUID
716 tristate "/dev/cpu/*/cpuid - CPU information support"
717 help
718 This device gives processes access to the x86 CPUID instruction to
719 be executed on a specific processor. It is a character device
720 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
721 /dev/cpu/31/cpuid.
723 choice
724 prompt "High Memory Support"
725 default HIGHMEM4G if !X86_NUMAQ
726 default HIGHMEM64G if X86_NUMAQ
727 depends on X86_32
729 config NOHIGHMEM
730 bool "off"
731 depends on !X86_NUMAQ
732 ---help---
733 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
734 However, the address space of 32-bit x86 processors is only 4
735 Gigabytes large. That means that, if you have a large amount of
736 physical memory, not all of it can be "permanently mapped" by the
737 kernel. The physical memory that's not permanently mapped is called
738 "high memory".
740 If you are compiling a kernel which will never run on a machine with
741 more than 1 Gigabyte total physical RAM, answer "off" here (default
742 choice and suitable for most users). This will result in a "3GB/1GB"
743 split: 3GB are mapped so that each process sees a 3GB virtual memory
744 space and the remaining part of the 4GB virtual memory space is used
745 by the kernel to permanently map as much physical memory as
746 possible.
748 If the machine has between 1 and 4 Gigabytes physical RAM, then
749 answer "4GB" here.
751 If more than 4 Gigabytes is used then answer "64GB" here. This
752 selection turns Intel PAE (Physical Address Extension) mode on.
753 PAE implements 3-level paging on IA32 processors. PAE is fully
754 supported by Linux, PAE mode is implemented on all recent Intel
755 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
756 then the kernel will not boot on CPUs that don't support PAE!
758 The actual amount of total physical memory will either be
759 auto detected or can be forced by using a kernel command line option
760 such as "mem=256M". (Try "man bootparam" or see the documentation of
761 your boot loader (lilo or loadlin) about how to pass options to the
762 kernel at boot time.)
764 If unsure, say "off".
766 config HIGHMEM4G
767 bool "4GB"
768 depends on !X86_NUMAQ
769 help
770 Select this if you have a 32-bit processor and between 1 and 4
771 gigabytes of physical RAM.
773 config HIGHMEM64G
774 bool "64GB"
775 depends on !M386 && !M486
776 select X86_PAE
777 help
778 Select this if you have a 32-bit processor and more than 4
779 gigabytes of physical RAM.
781 endchoice
783 choice
784 depends on EXPERIMENTAL
785 prompt "Memory split" if EMBEDDED
786 default VMSPLIT_3G
787 depends on X86_32
788 help
789 Select the desired split between kernel and user memory.
791 If the address range available to the kernel is less than the
792 physical memory installed, the remaining memory will be available
793 as "high memory". Accessing high memory is a little more costly
794 than low memory, as it needs to be mapped into the kernel first.
795 Note that increasing the kernel address space limits the range
796 available to user programs, making the address space there
797 tighter. Selecting anything other than the default 3G/1G split
798 will also likely make your kernel incompatible with binary-only
799 kernel modules.
801 If you are not absolutely sure what you are doing, leave this
802 option alone!
804 config VMSPLIT_3G
805 bool "3G/1G user/kernel split"
806 config VMSPLIT_3G_OPT
807 depends on !X86_PAE
808 bool "3G/1G user/kernel split (for full 1G low memory)"
809 config VMSPLIT_2G
810 bool "2G/2G user/kernel split"
811 config VMSPLIT_2G_OPT
812 depends on !X86_PAE
813 bool "2G/2G user/kernel split (for full 2G low memory)"
814 config VMSPLIT_1G
815 bool "1G/3G user/kernel split"
816 endchoice
818 config PAGE_OFFSET
819 hex
820 default 0xB0000000 if VMSPLIT_3G_OPT
821 default 0x80000000 if VMSPLIT_2G
822 default 0x78000000 if VMSPLIT_2G_OPT
823 default 0x40000000 if VMSPLIT_1G
824 default 0xC0000000
825 depends on X86_32
827 config HIGHMEM
828 def_bool y
829 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
831 config X86_PAE
832 def_bool n
833 prompt "PAE (Physical Address Extension) Support"
834 depends on X86_32 && !HIGHMEM4G
835 select RESOURCES_64BIT
836 help
837 PAE is required for NX support, and furthermore enables
838 larger swapspace support for non-overcommit purposes. It
839 has the cost of more pagetable lookup overhead, and also
840 consumes more pagetable space per process.
842 # Common NUMA Features
843 config NUMA
844 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
845 depends on SMP
846 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
847 default n if X86_PC
848 default y if (X86_NUMAQ || X86_SUMMIT)
849 help
850 Enable NUMA (Non Uniform Memory Access) support.
851 The kernel will try to allocate memory used by a CPU on the
852 local memory controller of the CPU and add some more
853 NUMA awareness to the kernel.
855 For i386 this is currently highly experimental and should be only
856 used for kernel development. It might also cause boot failures.
857 For x86_64 this is recommended on all multiprocessor Opteron systems.
858 If the system is EM64T, you should say N unless your system is
859 EM64T NUMA.
861 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
862 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
864 config K8_NUMA
865 def_bool y
866 prompt "Old style AMD Opteron NUMA detection"
867 depends on X86_64 && NUMA && PCI
868 help
869 Enable K8 NUMA node topology detection. You should say Y here if
870 you have a multi processor AMD K8 system. This uses an old
871 method to read the NUMA configuration directly from the builtin
872 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
873 instead, which also takes priority if both are compiled in.
875 config X86_64_ACPI_NUMA
876 def_bool y
877 prompt "ACPI NUMA detection"
878 depends on X86_64 && NUMA && ACPI && PCI
879 select ACPI_NUMA
880 help
881 Enable ACPI SRAT based node topology detection.
883 config NUMA_EMU
884 bool "NUMA emulation"
885 depends on X86_64 && NUMA
886 help
887 Enable NUMA emulation. A flat machine will be split
888 into virtual nodes when booted with "numa=fake=N", where N is the
889 number of nodes. This is only useful for debugging.
891 config NODES_SHIFT
892 int
893 range 1 15 if X86_64
894 default "6" if X86_64
895 default "4" if X86_NUMAQ
896 default "3"
897 depends on NEED_MULTIPLE_NODES
899 config HAVE_ARCH_BOOTMEM_NODE
900 def_bool y
901 depends on X86_32 && NUMA
903 config ARCH_HAVE_MEMORY_PRESENT
904 def_bool y
905 depends on X86_32 && DISCONTIGMEM
907 config NEED_NODE_MEMMAP_SIZE
908 def_bool y
909 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
911 config HAVE_ARCH_ALLOC_REMAP
912 def_bool y
913 depends on X86_32 && NUMA
915 config ARCH_FLATMEM_ENABLE
916 def_bool y
917 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
919 config ARCH_DISCONTIGMEM_ENABLE
920 def_bool y
921 depends on NUMA && X86_32
923 config ARCH_DISCONTIGMEM_DEFAULT
924 def_bool y
925 depends on NUMA && X86_32
927 config ARCH_SPARSEMEM_DEFAULT
928 def_bool y
929 depends on X86_64
931 config ARCH_SPARSEMEM_ENABLE
932 def_bool y
933 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
934 select SPARSEMEM_STATIC if X86_32
935 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
937 config ARCH_SELECT_MEMORY_MODEL
938 def_bool y
939 depends on ARCH_SPARSEMEM_ENABLE
941 config ARCH_MEMORY_PROBE
942 def_bool X86_64
943 depends on MEMORY_HOTPLUG
945 source "mm/Kconfig"
947 config HIGHPTE
948 bool "Allocate 3rd-level pagetables from highmem"
949 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
950 help
951 The VM uses one page table entry for each page of physical memory.
952 For systems with a lot of RAM, this can be wasteful of precious
953 low memory. Setting this option will put user-space page table
954 entries in high memory.
956 config MATH_EMULATION
957 bool
958 prompt "Math emulation" if X86_32
959 ---help---
960 Linux can emulate a math coprocessor (used for floating point
961 operations) if you don't have one. 486DX and Pentium processors have
962 a math coprocessor built in, 486SX and 386 do not, unless you added
963 a 487DX or 387, respectively. (The messages during boot time can
964 give you some hints here ["man dmesg"].) Everyone needs either a
965 coprocessor or this emulation.
967 If you don't have a math coprocessor, you need to say Y here; if you
968 say Y here even though you have a coprocessor, the coprocessor will
969 be used nevertheless. (This behavior can be changed with the kernel
970 command line option "no387", which comes handy if your coprocessor
971 is broken. Try "man bootparam" or see the documentation of your boot
972 loader (lilo or loadlin) about how to pass options to the kernel at
973 boot time.) This means that it is a good idea to say Y here if you
974 intend to use this kernel on different machines.
976 More information about the internals of the Linux math coprocessor
977 emulation can be found in <file:arch/x86/math-emu/README>.
979 If you are not sure, say Y; apart from resulting in a 66 KB bigger
980 kernel, it won't hurt.
982 config MTRR
983 bool "MTRR (Memory Type Range Register) support"
984 ---help---
985 On Intel P6 family processors (Pentium Pro, Pentium II and later)
986 the Memory Type Range Registers (MTRRs) may be used to control
987 processor access to memory ranges. This is most useful if you have
988 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
989 allows bus write transfers to be combined into a larger transfer
990 before bursting over the PCI/AGP bus. This can increase performance
991 of image write operations 2.5 times or more. Saying Y here creates a
992 /proc/mtrr file which may be used to manipulate your processor's
993 MTRRs. Typically the X server should use this.
995 This code has a reasonably generic interface so that similar
996 control registers on other processors can be easily supported
997 as well:
999 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1000 Registers (ARRs) which provide a similar functionality to MTRRs. For
1001 these, the ARRs are used to emulate the MTRRs.
1002 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1003 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1004 write-combining. All of these processors are supported by this code
1005 and it makes sense to say Y here if you have one of them.
1007 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1008 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1009 can lead to all sorts of problems, so it's good to say Y here.
1011 You can safely say Y even if your machine doesn't have MTRRs, you'll
1012 just add about 9 KB to your kernel.
1014 See <file:Documentation/mtrr.txt> for more information.
1016 config EFI
1017 def_bool n
1018 prompt "EFI runtime service support"
1019 depends on ACPI
1020 ---help---
1021 This enables the kernel to use EFI runtime services that are
1022 available (such as the EFI variable services).
1024 This option is only useful on systems that have EFI firmware.
1025 In addition, you should use the latest ELILO loader available
1026 at <http://elilo.sourceforge.net> in order to take advantage
1027 of EFI runtime services. However, even with this option, the
1028 resultant kernel should continue to boot on existing non-EFI
1029 platforms.
1031 config IRQBALANCE
1032 def_bool y
1033 prompt "Enable kernel irq balancing"
1034 depends on X86_32 && SMP && X86_IO_APIC
1035 help
1036 The default yes will allow the kernel to do irq load balancing.
1037 Saying no will keep the kernel from doing irq load balancing.
1039 config SECCOMP
1040 def_bool y
1041 prompt "Enable seccomp to safely compute untrusted bytecode"
1042 depends on PROC_FS
1043 help
1044 This kernel feature is useful for number crunching applications
1045 that may need to compute untrusted bytecode during their
1046 execution. By using pipes or other transports made available to
1047 the process as file descriptors supporting the read/write
1048 syscalls, it's possible to isolate those applications in
1049 their own address space using seccomp. Once seccomp is
1050 enabled via /proc/<pid>/seccomp, it cannot be disabled
1051 and the task is only allowed to execute a few safe syscalls
1052 defined by each seccomp mode.
1054 If unsure, say Y. Only embedded should say N here.
1056 config CC_STACKPROTECTOR
1057 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1058 depends on X86_64 && EXPERIMENTAL && BROKEN
1059 help
1060 This option turns on the -fstack-protector GCC feature. This
1061 feature puts, at the beginning of critical functions, a canary
1062 value on the stack just before the return address, and validates
1063 the value just before actually returning. Stack based buffer
1064 overflows (that need to overwrite this return address) now also
1065 overwrite the canary, which gets detected and the attack is then
1066 neutralized via a kernel panic.
1068 This feature requires gcc version 4.2 or above, or a distribution
1069 gcc with the feature backported. Older versions are automatically
1070 detected and for those versions, this configuration option is ignored.
1072 config CC_STACKPROTECTOR_ALL
1073 bool "Use stack-protector for all functions"
1074 depends on CC_STACKPROTECTOR
1075 help
1076 Normally, GCC only inserts the canary value protection for
1077 functions that use large-ish on-stack buffers. By enabling
1078 this option, GCC will be asked to do this for ALL functions.
1080 source kernel/Kconfig.hz
1082 config KEXEC
1083 bool "kexec system call"
1084 help
1085 kexec is a system call that implements the ability to shutdown your
1086 current kernel, and to start another kernel. It is like a reboot
1087 but it is independent of the system firmware. And like a reboot
1088 you can start any kernel with it, not just Linux.
1090 The name comes from the similarity to the exec system call.
1092 It is an ongoing process to be certain the hardware in a machine
1093 is properly shutdown, so do not be surprised if this code does not
1094 initially work for you. It may help to enable device hotplugging
1095 support. As of this writing the exact hardware interface is
1096 strongly in flux, so no good recommendation can be made.
1098 config CRASH_DUMP
1099 bool "kernel crash dumps (EXPERIMENTAL)"
1100 depends on EXPERIMENTAL
1101 depends on X86_64 || (X86_32 && HIGHMEM)
1102 help
1103 Generate crash dump after being started by kexec.
1104 This should be normally only set in special crash dump kernels
1105 which are loaded in the main kernel with kexec-tools into
1106 a specially reserved region and then later executed after
1107 a crash by kdump/kexec. The crash dump kernel must be compiled
1108 to a memory address not used by the main kernel or BIOS using
1109 PHYSICAL_START, or it must be built as a relocatable image
1110 (CONFIG_RELOCATABLE=y).
1111 For more details see Documentation/kdump/kdump.txt
1113 config PHYSICAL_START
1114 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1115 default "0x1000000" if X86_NUMAQ
1116 default "0x200000" if X86_64
1117 default "0x100000"
1118 help
1119 This gives the physical address where the kernel is loaded.
1121 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1122 bzImage will decompress itself to above physical address and
1123 run from there. Otherwise, bzImage will run from the address where
1124 it has been loaded by the boot loader and will ignore above physical
1125 address.
1127 In normal kdump cases one does not have to set/change this option
1128 as now bzImage can be compiled as a completely relocatable image
1129 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1130 address. This option is mainly useful for the folks who don't want
1131 to use a bzImage for capturing the crash dump and want to use a
1132 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1133 to be specifically compiled to run from a specific memory area
1134 (normally a reserved region) and this option comes handy.
1136 So if you are using bzImage for capturing the crash dump, leave
1137 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1138 Otherwise if you plan to use vmlinux for capturing the crash dump
1139 change this value to start of the reserved region (Typically 16MB
1140 0x1000000). In other words, it can be set based on the "X" value as
1141 specified in the "crashkernel=YM@XM" command line boot parameter
1142 passed to the panic-ed kernel. Typically this parameter is set as
1143 crashkernel=64M@16M. Please take a look at
1144 Documentation/kdump/kdump.txt for more details about crash dumps.
1146 Usage of bzImage for capturing the crash dump is recommended as
1147 one does not have to build two kernels. Same kernel can be used
1148 as production kernel and capture kernel. Above option should have
1149 gone away after relocatable bzImage support is introduced. But it
1150 is present because there are users out there who continue to use
1151 vmlinux for dump capture. This option should go away down the
1152 line.
1154 Don't change this unless you know what you are doing.
1156 config RELOCATABLE
1157 bool "Build a relocatable kernel (EXPERIMENTAL)"
1158 depends on EXPERIMENTAL
1159 help
1160 This builds a kernel image that retains relocation information
1161 so it can be loaded someplace besides the default 1MB.
1162 The relocations tend to make the kernel binary about 10% larger,
1163 but are discarded at runtime.
1165 One use is for the kexec on panic case where the recovery kernel
1166 must live at a different physical address than the primary
1167 kernel.
1169 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1170 it has been loaded at and the compile time physical address
1171 (CONFIG_PHYSICAL_START) is ignored.
1173 config PHYSICAL_ALIGN
1174 hex
1175 prompt "Alignment value to which kernel should be aligned" if X86_32
1176 default "0x100000" if X86_32
1177 default "0x200000" if X86_64
1178 range 0x2000 0x400000
1179 help
1180 This value puts the alignment restrictions on physical address
1181 where kernel is loaded and run from. Kernel is compiled for an
1182 address which meets above alignment restriction.
1184 If bootloader loads the kernel at a non-aligned address and
1185 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1186 address aligned to above value and run from there.
1188 If bootloader loads the kernel at a non-aligned address and
1189 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1190 load address and decompress itself to the address it has been
1191 compiled for and run from there. The address for which kernel is
1192 compiled already meets above alignment restrictions. Hence the
1193 end result is that kernel runs from a physical address meeting
1194 above alignment restrictions.
1196 Don't change this unless you know what you are doing.
1198 config HOTPLUG_CPU
1199 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1200 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1201 ---help---
1202 Say Y here to experiment with turning CPUs off and on, and to
1203 enable suspend on SMP systems. CPUs can be controlled through
1204 /sys/devices/system/cpu.
1205 Say N if you want to disable CPU hotplug and don't need to
1206 suspend.
1208 config COMPAT_VDSO
1209 def_bool y
1210 prompt "Compat VDSO support"
1211 depends on X86_32 || IA32_EMULATION
1212 help
1213 Map the 32-bit VDSO to the predictable old-style address too.
1214 ---help---
1215 Say N here if you are running a sufficiently recent glibc
1216 version (2.3.3 or later), to remove the high-mapped
1217 VDSO mapping and to exclusively use the randomized VDSO.
1219 If unsure, say Y.
1221 endmenu
1223 config ARCH_ENABLE_MEMORY_HOTPLUG
1224 def_bool y
1225 depends on X86_64 || (X86_32 && HIGHMEM)
1227 config HAVE_ARCH_EARLY_PFN_TO_NID
1228 def_bool X86_64
1229 depends on NUMA
1231 menu "Power management options"
1232 depends on !X86_VOYAGER
1234 config ARCH_HIBERNATION_HEADER
1235 def_bool y
1236 depends on X86_64 && HIBERNATION
1238 source "kernel/power/Kconfig"
1240 source "drivers/acpi/Kconfig"
1242 config X86_APM_BOOT
1243 bool
1244 default y
1245 depends on APM || APM_MODULE
1247 menuconfig APM
1248 tristate "APM (Advanced Power Management) BIOS support"
1249 depends on X86_32 && PM_SLEEP && !X86_VISWS
1250 ---help---
1251 APM is a BIOS specification for saving power using several different
1252 techniques. This is mostly useful for battery powered laptops with
1253 APM compliant BIOSes. If you say Y here, the system time will be
1254 reset after a RESUME operation, the /proc/apm device will provide
1255 battery status information, and user-space programs will receive
1256 notification of APM "events" (e.g. battery status change).
1258 If you select "Y" here, you can disable actual use of the APM
1259 BIOS by passing the "apm=off" option to the kernel at boot time.
1261 Note that the APM support is almost completely disabled for
1262 machines with more than one CPU.
1264 In order to use APM, you will need supporting software. For location
1265 and more information, read <file:Documentation/pm.txt> and the
1266 Battery Powered Linux mini-HOWTO, available from
1267 <http://www.tldp.org/docs.html#howto>.
1269 This driver does not spin down disk drives (see the hdparm(8)
1270 manpage ("man 8 hdparm") for that), and it doesn't turn off
1271 VESA-compliant "green" monitors.
1273 This driver does not support the TI 4000M TravelMate and the ACER
1274 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1275 desktop machines also don't have compliant BIOSes, and this driver
1276 may cause those machines to panic during the boot phase.
1278 Generally, if you don't have a battery in your machine, there isn't
1279 much point in using this driver and you should say N. If you get
1280 random kernel OOPSes or reboots that don't seem to be related to
1281 anything, try disabling/enabling this option (or disabling/enabling
1282 APM in your BIOS).
1284 Some other things you should try when experiencing seemingly random,
1285 "weird" problems:
1287 1) make sure that you have enough swap space and that it is
1288 enabled.
1289 2) pass the "no-hlt" option to the kernel
1290 3) switch on floating point emulation in the kernel and pass
1291 the "no387" option to the kernel
1292 4) pass the "floppy=nodma" option to the kernel
1293 5) pass the "mem=4M" option to the kernel (thereby disabling
1294 all but the first 4 MB of RAM)
1295 6) make sure that the CPU is not over clocked.
1296 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1297 8) disable the cache from your BIOS settings
1298 9) install a fan for the video card or exchange video RAM
1299 10) install a better fan for the CPU
1300 11) exchange RAM chips
1301 12) exchange the motherboard.
1303 To compile this driver as a module, choose M here: the
1304 module will be called apm.
1306 if APM
1308 config APM_IGNORE_USER_SUSPEND
1309 bool "Ignore USER SUSPEND"
1310 help
1311 This option will ignore USER SUSPEND requests. On machines with a
1312 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1313 series notebooks, it is necessary to say Y because of a BIOS bug.
1315 config APM_DO_ENABLE
1316 bool "Enable PM at boot time"
1317 ---help---
1318 Enable APM features at boot time. From page 36 of the APM BIOS
1319 specification: "When disabled, the APM BIOS does not automatically
1320 power manage devices, enter the Standby State, enter the Suspend
1321 State, or take power saving steps in response to CPU Idle calls."
1322 This driver will make CPU Idle calls when Linux is idle (unless this
1323 feature is turned off -- see "Do CPU IDLE calls", below). This
1324 should always save battery power, but more complicated APM features
1325 will be dependent on your BIOS implementation. You may need to turn
1326 this option off if your computer hangs at boot time when using APM
1327 support, or if it beeps continuously instead of suspending. Turn
1328 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1329 T400CDT. This is off by default since most machines do fine without
1330 this feature.
1332 config APM_CPU_IDLE
1333 bool "Make CPU Idle calls when idle"
1334 help
1335 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1336 On some machines, this can activate improved power savings, such as
1337 a slowed CPU clock rate, when the machine is idle. These idle calls
1338 are made after the idle loop has run for some length of time (e.g.,
1339 333 mS). On some machines, this will cause a hang at boot time or
1340 whenever the CPU becomes idle. (On machines with more than one CPU,
1341 this option does nothing.)
1343 config APM_DISPLAY_BLANK
1344 bool "Enable console blanking using APM"
1345 help
1346 Enable console blanking using the APM. Some laptops can use this to
1347 turn off the LCD backlight when the screen blanker of the Linux
1348 virtual console blanks the screen. Note that this is only used by
1349 the virtual console screen blanker, and won't turn off the backlight
1350 when using the X Window system. This also doesn't have anything to
1351 do with your VESA-compliant power-saving monitor. Further, this
1352 option doesn't work for all laptops -- it might not turn off your
1353 backlight at all, or it might print a lot of errors to the console,
1354 especially if you are using gpm.
1356 config APM_ALLOW_INTS
1357 bool "Allow interrupts during APM BIOS calls"
1358 help
1359 Normally we disable external interrupts while we are making calls to
1360 the APM BIOS as a measure to lessen the effects of a badly behaving
1361 BIOS implementation. The BIOS should reenable interrupts if it
1362 needs to. Unfortunately, some BIOSes do not -- especially those in
1363 many of the newer IBM Thinkpads. If you experience hangs when you
1364 suspend, try setting this to Y. Otherwise, say N.
1366 config APM_REAL_MODE_POWER_OFF
1367 bool "Use real mode APM BIOS call to power off"
1368 help
1369 Use real mode APM BIOS calls to switch off the computer. This is
1370 a work-around for a number of buggy BIOSes. Switch this option on if
1371 your computer crashes instead of powering off properly.
1373 endif # APM
1375 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1377 source "drivers/cpuidle/Kconfig"
1379 endmenu
1382 menu "Bus options (PCI etc.)"
1384 config PCI
1385 bool "PCI support" if !X86_VISWS
1386 depends on !X86_VOYAGER
1387 default y
1388 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1389 help
1390 Find out whether you have a PCI motherboard. PCI is the name of a
1391 bus system, i.e. the way the CPU talks to the other stuff inside
1392 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1393 VESA. If you have PCI, say Y, otherwise N.
1395 choice
1396 prompt "PCI access mode"
1397 depends on X86_32 && PCI && !X86_VISWS
1398 default PCI_GOANY
1399 ---help---
1400 On PCI systems, the BIOS can be used to detect the PCI devices and
1401 determine their configuration. However, some old PCI motherboards
1402 have BIOS bugs and may crash if this is done. Also, some embedded
1403 PCI-based systems don't have any BIOS at all. Linux can also try to
1404 detect the PCI hardware directly without using the BIOS.
1406 With this option, you can specify how Linux should detect the
1407 PCI devices. If you choose "BIOS", the BIOS will be used,
1408 if you choose "Direct", the BIOS won't be used, and if you
1409 choose "MMConfig", then PCI Express MMCONFIG will be used.
1410 If you choose "Any", the kernel will try MMCONFIG, then the
1411 direct access method and falls back to the BIOS if that doesn't
1412 work. If unsure, go with the default, which is "Any".
1414 config PCI_GOBIOS
1415 bool "BIOS"
1417 config PCI_GOMMCONFIG
1418 bool "MMConfig"
1420 config PCI_GODIRECT
1421 bool "Direct"
1423 config PCI_GOANY
1424 bool "Any"
1426 endchoice
1428 config PCI_BIOS
1429 def_bool y
1430 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1432 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1433 config PCI_DIRECT
1434 def_bool y
1435 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1437 config PCI_MMCONFIG
1438 def_bool y
1439 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1441 config PCI_DOMAINS
1442 def_bool y
1443 depends on PCI
1445 config PCI_MMCONFIG
1446 bool "Support mmconfig PCI config space access"
1447 depends on X86_64 && PCI && ACPI
1449 config DMAR
1450 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1451 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1452 help
1453 DMA remapping (DMAR) devices support enables independent address
1454 translations for Direct Memory Access (DMA) from devices.
1455 These DMA remapping devices are reported via ACPI tables
1456 and include PCI device scope covered by these DMA
1457 remapping devices.
1459 config DMAR_GFX_WA
1460 def_bool y
1461 prompt "Support for Graphics workaround"
1462 depends on DMAR
1463 help
1464 Current Graphics drivers tend to use physical address
1465 for DMA and avoid using DMA APIs. Setting this config
1466 option permits the IOMMU driver to set a unity map for
1467 all the OS-visible memory. Hence the driver can continue
1468 to use physical addresses for DMA.
1470 config DMAR_FLOPPY_WA
1471 def_bool y
1472 depends on DMAR
1473 help
1474 Floppy disk drivers are know to bypass DMA API calls
1475 thereby failing to work when IOMMU is enabled. This
1476 workaround will setup a 1:1 mapping for the first
1477 16M to make floppy (an ISA device) work.
1479 source "drivers/pci/pcie/Kconfig"
1481 source "drivers/pci/Kconfig"
1483 # x86_64 have no ISA slots, but do have ISA-style DMA.
1484 config ISA_DMA_API
1485 def_bool y
1487 if X86_32
1489 config ISA
1490 bool "ISA support"
1491 depends on !(X86_VOYAGER || X86_VISWS)
1492 help
1493 Find out whether you have ISA slots on your motherboard. ISA is the
1494 name of a bus system, i.e. the way the CPU talks to the other stuff
1495 inside your box. Other bus systems are PCI, EISA, MicroChannel
1496 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1497 newer boards don't support it. If you have ISA, say Y, otherwise N.
1499 config EISA
1500 bool "EISA support"
1501 depends on ISA
1502 ---help---
1503 The Extended Industry Standard Architecture (EISA) bus was
1504 developed as an open alternative to the IBM MicroChannel bus.
1506 The EISA bus provided some of the features of the IBM MicroChannel
1507 bus while maintaining backward compatibility with cards made for
1508 the older ISA bus. The EISA bus saw limited use between 1988 and
1509 1995 when it was made obsolete by the PCI bus.
1511 Say Y here if you are building a kernel for an EISA-based machine.
1513 Otherwise, say N.
1515 source "drivers/eisa/Kconfig"
1517 config MCA
1518 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1519 default y if X86_VOYAGER
1520 help
1521 MicroChannel Architecture is found in some IBM PS/2 machines and
1522 laptops. It is a bus system similar to PCI or ISA. See
1523 <file:Documentation/mca.txt> (and especially the web page given
1524 there) before attempting to build an MCA bus kernel.
1526 source "drivers/mca/Kconfig"
1528 config SCx200
1529 tristate "NatSemi SCx200 support"
1530 depends on !X86_VOYAGER
1531 help
1532 This provides basic support for National Semiconductor's
1533 (now AMD's) Geode processors. The driver probes for the
1534 PCI-IDs of several on-chip devices, so its a good dependency
1535 for other scx200_* drivers.
1537 If compiled as a module, the driver is named scx200.
1539 config SCx200HR_TIMER
1540 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1541 depends on SCx200 && GENERIC_TIME
1542 default y
1543 help
1544 This driver provides a clocksource built upon the on-chip
1545 27MHz high-resolution timer. Its also a workaround for
1546 NSC Geode SC-1100's buggy TSC, which loses time when the
1547 processor goes idle (as is done by the scheduler). The
1548 other workaround is idle=poll boot option.
1550 config GEODE_MFGPT_TIMER
1551 def_bool y
1552 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1553 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1554 help
1555 This driver provides a clock event source based on the MFGPT
1556 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1557 MFGPTs have a better resolution and max interval than the
1558 generic PIT, and are suitable for use as high-res timers.
1560 endif # X86_32
1562 config K8_NB
1563 def_bool y
1564 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1566 source "drivers/pcmcia/Kconfig"
1568 source "drivers/pci/hotplug/Kconfig"
1570 endmenu
1573 menu "Executable file formats / Emulations"
1575 source "fs/Kconfig.binfmt"
1577 config IA32_EMULATION
1578 bool "IA32 Emulation"
1579 depends on X86_64
1580 select COMPAT_BINFMT_ELF
1581 help
1582 Include code to run 32-bit programs under a 64-bit kernel. You should
1583 likely turn this on, unless you're 100% sure that you don't have any
1584 32-bit programs left.
1586 config IA32_AOUT
1587 tristate "IA32 a.out support"
1588 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1589 help
1590 Support old a.out binaries in the 32bit emulation.
1592 config COMPAT
1593 def_bool y
1594 depends on IA32_EMULATION
1596 config COMPAT_FOR_U64_ALIGNMENT
1597 def_bool COMPAT
1598 depends on X86_64
1600 config SYSVIPC_COMPAT
1601 def_bool y
1602 depends on X86_64 && COMPAT && SYSVIPC
1604 endmenu
1607 source "net/Kconfig"
1609 source "drivers/Kconfig"
1611 source "drivers/firmware/Kconfig"
1613 source "fs/Kconfig"
1615 source "arch/x86/Kconfig.debug"
1617 source "security/Kconfig"
1619 source "crypto/Kconfig"
1621 source "arch/x86/kvm/Kconfig"
1623 source "lib/Kconfig"