| blob | 65594884f32f4e500e522a684282919a8fd78028 |
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_OPROFILE
23 config GENERIC_LOCKBREAK
24 def_bool n
26 config GENERIC_TIME
27 def_bool y
29 config GENERIC_CMOS_UPDATE
30 def_bool y
32 config CLOCKSOURCE_WATCHDOG
33 def_bool y
35 config GENERIC_CLOCKEVENTS
36 def_bool y
38 config GENERIC_CLOCKEVENTS_BROADCAST
39 def_bool y
40 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
42 config LOCKDEP_SUPPORT
43 def_bool y
45 config STACKTRACE_SUPPORT
46 def_bool y
48 config HAVE_LATENCYTOP_SUPPORT
49 def_bool y
51 config SEMAPHORE_SLEEPERS
52 def_bool y
54 config MMU
55 def_bool y
57 config ZONE_DMA
58 def_bool y
60 config QUICKLIST
61 def_bool X86_32
63 config SBUS
64 bool
66 config GENERIC_ISA_DMA
67 def_bool y
69 config GENERIC_IOMAP
70 def_bool y
72 config GENERIC_BUG
73 def_bool y
74 depends on BUG
76 config GENERIC_HWEIGHT
77 def_bool y
79 config GENERIC_GPIO
80 def_bool n
82 config ARCH_MAY_HAVE_PC_FDC
83 def_bool y
85 config DMI
86 def_bool y
88 config RWSEM_GENERIC_SPINLOCK
89 def_bool !X86_XADD
91 config RWSEM_XCHGADD_ALGORITHM
92 def_bool X86_XADD
94 config ARCH_HAS_ILOG2_U32
95 def_bool n
97 config ARCH_HAS_ILOG2_U64
98 def_bool n
100 config GENERIC_CALIBRATE_DELAY
101 def_bool y
103 config GENERIC_TIME_VSYSCALL
104 bool
105 default X86_64
107 config HAVE_SETUP_PER_CPU_AREA
108 def_bool X86_64
110 select HAVE_KVM
112 config ARCH_HIBERNATION_POSSIBLE
113 def_bool y
114 depends on !SMP || !X86_VOYAGER
116 config ARCH_SUSPEND_POSSIBLE
117 def_bool y
118 depends on !X86_VOYAGER
120 config ZONE_DMA32
121 bool
122 default X86_64
124 config ARCH_POPULATES_NODE_MAP
125 def_bool y
127 config AUDIT_ARCH
128 bool
129 default X86_64
131 # Use the generic interrupt handling code in kernel/irq/:
132 config GENERIC_HARDIRQS
133 bool
134 default y
136 config GENERIC_IRQ_PROBE
137 bool
138 default y
140 config GENERIC_PENDING_IRQ
141 bool
142 depends on GENERIC_HARDIRQS && SMP
143 default y
145 config X86_SMP
146 bool
147 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
148 default y
150 config X86_32_SMP
151 def_bool y
152 depends on X86_32 && SMP
154 config X86_64_SMP
155 def_bool y
156 depends on X86_64 && SMP
158 config X86_HT
159 bool
160 depends on SMP
161 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || (X86_64 && !MK8)
162 default y
164 config X86_BIOS_REBOOT
165 bool
166 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
167 default y
169 config X86_TRAMPOLINE
170 bool
171 depends on X86_SMP || (X86_VOYAGER && SMP)
172 default y
174 config KTIME_SCALAR
175 def_bool X86_32
176 source "init/Kconfig"
178 menu "Processor type and features"
180 source "kernel/time/Kconfig"
182 config SMP
183 bool "Symmetric multi-processing support"
184 ---help---
185 This enables support for systems with more than one CPU. If you have
186 a system with only one CPU, like most personal computers, say N. If
187 you have a system with more than one CPU, say Y.
189 If you say N here, the kernel will run on single and multiprocessor
190 machines, but will use only one CPU of a multiprocessor machine. If
191 you say Y here, the kernel will run on many, but not all,
192 singleprocessor machines. On a singleprocessor machine, the kernel
193 will run faster if you say N here.
195 Note that if you say Y here and choose architecture "586" or
196 "Pentium" under "Processor family", the kernel will not work on 486
197 architectures. Similarly, multiprocessor kernels for the "PPro"
198 architecture may not work on all Pentium based boards.
200 People using multiprocessor machines who say Y here should also say
201 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
202 Management" code will be disabled if you say Y here.
204 See also the <file:Documentation/smp.txt>,
205 <file:Documentation/i386/IO-APIC.txt>,
206 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
207 <http://www.tldp.org/docs.html#howto>.
209 If you don't know what to do here, say N.
211 choice
212 prompt "Subarchitecture Type"
213 default X86_PC
215 config X86_PC
216 bool "PC-compatible"
217 help
218 Choose this option if your computer is a standard PC or compatible.
220 config X86_ELAN
221 bool "AMD Elan"
222 depends on X86_32
223 help
224 Select this for an AMD Elan processor.
226 Do not use this option for K6/Athlon/Opteron processors!
228 If unsure, choose "PC-compatible" instead.
230 config X86_VOYAGER
231 bool "Voyager (NCR)"
232 depends on X86_32
233 select SMP if !BROKEN
234 help
235 Voyager is an MCA-based 32-way capable SMP architecture proprietary
236 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
238 *** WARNING ***
240 If you do not specifically know you have a Voyager based machine,
241 say N here, otherwise the kernel you build will not be bootable.
243 config X86_NUMAQ
244 bool "NUMAQ (IBM/Sequent)"
245 select SMP
246 select NUMA
247 depends on X86_32
248 help
249 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
250 multiquad box. This changes the way that processors are bootstrapped,
251 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
252 You will need a new lynxer.elf file to flash your firmware with - send
253 email to <Martin.Bligh@us.ibm.com>.
255 config X86_SUMMIT
256 bool "Summit/EXA (IBM x440)"
257 depends on X86_32 && SMP
258 help
259 This option is needed for IBM systems that use the Summit/EXA chipset.
260 In particular, it is needed for the x440.
262 If you don't have one of these computers, you should say N here.
263 If you want to build a NUMA kernel, you must select ACPI.
265 config X86_BIGSMP
266 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
267 depends on X86_32 && SMP
268 help
269 This option is needed for the systems that have more than 8 CPUs
270 and if the system is not of any sub-arch type above.
272 If you don't have such a system, you should say N here.
274 config X86_VISWS
275 bool "SGI 320/540 (Visual Workstation)"
276 depends on X86_32
277 help
278 The SGI Visual Workstation series is an IA32-based workstation
279 based on SGI systems chips with some legacy PC hardware attached.
281 Say Y here to create a kernel to run on the SGI 320 or 540.
283 A kernel compiled for the Visual Workstation will not run on PCs
284 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
286 config X86_GENERICARCH
287 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
288 depends on X86_32
289 help
290 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
291 It is intended for a generic binary kernel.
292 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
294 config X86_ES7000
295 bool "Support for Unisys ES7000 IA32 series"
296 depends on X86_32 && SMP
297 help
298 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
299 supposed to run on an IA32-based Unisys ES7000 system.
300 Only choose this option if you have such a system, otherwise you
301 should say N here.
303 config X86_RDC321X
304 bool "RDC R-321x SoC"
305 depends on X86_32
306 select M486
307 select X86_REBOOTFIXUPS
308 select GENERIC_GPIO
309 select LEDS_GPIO
310 help
311 This option is needed for RDC R-321x system-on-chip, also known
312 as R-8610-(G).
313 If you don't have one of these chips, you should say N here.
315 config X86_VSMP
316 bool "Support for ScaleMP vSMP"
317 depends on X86_64 && PCI
318 help
319 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
320 supposed to run on these EM64T-based machines. Only choose this option
321 if you have one of these machines.
323 endchoice
325 config SCHED_NO_NO_OMIT_FRAME_POINTER
326 def_bool y
327 prompt "Single-depth WCHAN output"
328 depends on X86_32
329 help
330 Calculate simpler /proc/<PID>/wchan values. If this option
331 is disabled then wchan values will recurse back to the
332 caller function. This provides more accurate wchan values,
333 at the expense of slightly more scheduling overhead.
335 If in doubt, say "Y".
337 menuconfig PARAVIRT_GUEST
338 bool "Paravirtualized guest support"
339 help
340 Say Y here to get to see options related to running Linux under
341 various hypervisors. This option alone does not add any kernel code.
343 If you say N, all options in this submenu will be skipped and disabled.
345 if PARAVIRT_GUEST
347 source "arch/x86/xen/Kconfig"
349 config VMI
350 bool "VMI Guest support"
351 select PARAVIRT
352 depends on X86_32
353 depends on !(X86_VISWS || X86_VOYAGER)
354 help
355 VMI provides a paravirtualized interface to the VMware ESX server
356 (it could be used by other hypervisors in theory too, but is not
357 at the moment), by linking the kernel to a GPL-ed ROM module
358 provided by the hypervisor.
360 source "arch/x86/lguest/Kconfig"
362 config PARAVIRT
363 bool "Enable paravirtualization code"
364 depends on !(X86_VISWS || X86_VOYAGER)
365 help
366 This changes the kernel so it can modify itself when it is run
367 under a hypervisor, potentially improving performance significantly
368 over full virtualization. However, when run without a hypervisor
369 the kernel is theoretically slower and slightly larger.
371 endif
373 config ACPI_SRAT
374 def_bool y
375 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
376 select ACPI_NUMA
378 config HAVE_ARCH_PARSE_SRAT
379 def_bool y
380 depends on ACPI_SRAT
382 config X86_SUMMIT_NUMA
383 def_bool y
384 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
386 config X86_CYCLONE_TIMER
387 def_bool y
388 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
390 config ES7000_CLUSTERED_APIC
391 def_bool y
392 depends on SMP && X86_ES7000 && MPENTIUMIII
394 source "arch/x86/Kconfig.cpu"
396 config HPET_TIMER
397 def_bool X86_64
398 prompt "HPET Timer Support" if X86_32
399 help
400 Use the IA-PC HPET (High Precision Event Timer) to manage
401 time in preference to the PIT and RTC, if a HPET is
402 present.
403 HPET is the next generation timer replacing legacy 8254s.
404 The HPET provides a stable time base on SMP
405 systems, unlike the TSC, but it is more expensive to access,
406 as it is off-chip. You can find the HPET spec at
407 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
409 You can safely choose Y here. However, HPET will only be
410 activated if the platform and the BIOS support this feature.
411 Otherwise the 8254 will be used for timing services.
413 Choose N to continue using the legacy 8254 timer.
415 config HPET_EMULATE_RTC
416 def_bool y
417 depends on HPET_TIMER && (RTC=y || RTC=m)
419 # Mark as embedded because too many people got it wrong.
420 # The code disables itself when not needed.
421 config GART_IOMMU
422 bool "GART IOMMU support" if EMBEDDED
423 default y
424 select SWIOTLB
425 select AGP
426 depends on X86_64 && PCI
427 help
428 Support for full DMA access of devices with 32bit memory access only
429 on systems with more than 3GB. This is usually needed for USB,
430 sound, many IDE/SATA chipsets and some other devices.
431 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
432 based hardware IOMMU and a software bounce buffer based IOMMU used
433 on Intel systems and as fallback.
434 The code is only active when needed (enough memory and limited
435 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
436 too.
438 config CALGARY_IOMMU
439 bool "IBM Calgary IOMMU support"
440 select SWIOTLB
441 depends on X86_64 && PCI && EXPERIMENTAL
442 help
443 Support for hardware IOMMUs in IBM's xSeries x366 and x460
444 systems. Needed to run systems with more than 3GB of memory
445 properly with 32-bit PCI devices that do not support DAC
446 (Double Address Cycle). Calgary also supports bus level
447 isolation, where all DMAs pass through the IOMMU. This
448 prevents them from going anywhere except their intended
449 destination. This catches hard-to-find kernel bugs and
450 mis-behaving drivers and devices that do not use the DMA-API
451 properly to set up their DMA buffers. The IOMMU can be
452 turned off at boot time with the iommu=off parameter.
453 Normally the kernel will make the right choice by itself.
454 If unsure, say Y.
456 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
457 def_bool y
458 prompt "Should Calgary be enabled by default?"
459 depends on CALGARY_IOMMU
460 help
461 Should Calgary be enabled by default? if you choose 'y', Calgary
462 will be used (if it exists). If you choose 'n', Calgary will not be
463 used even if it exists. If you choose 'n' and would like to use
464 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
465 If unsure, say Y.
467 # need this always selected by IOMMU for the VIA workaround
468 config SWIOTLB
469 bool
470 help
471 Support for software bounce buffers used on x86-64 systems
472 which don't have a hardware IOMMU (e.g. the current generation
473 of Intel's x86-64 CPUs). Using this PCI devices which can only
474 access 32-bits of memory can be used on systems with more than
475 3 GB of memory. If unsure, say Y.
478 config NR_CPUS
479 int "Maximum number of CPUs (2-255)"
480 range 2 255
481 depends on SMP
482 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
483 default "8"
484 help
485 This allows you to specify the maximum number of CPUs which this
486 kernel will support. The maximum supported value is 255 and the
487 minimum value which makes sense is 2.
489 This is purely to save memory - each supported CPU adds
490 approximately eight kilobytes to the kernel image.
492 config SCHED_SMT
493 bool "SMT (Hyperthreading) scheduler support"
494 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
495 help
496 SMT scheduler support improves the CPU scheduler's decision making
497 when dealing with Intel Pentium 4 chips with HyperThreading at a
498 cost of slightly increased overhead in some places. If unsure say
499 N here.
501 config SCHED_MC
502 def_bool y
503 prompt "Multi-core scheduler support"
504 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
505 help
506 Multi-core scheduler support improves the CPU scheduler's decision
507 making when dealing with multi-core CPU chips at a cost of slightly
508 increased overhead in some places. If unsure say N here.
510 source "kernel/Kconfig.preempt"
512 config X86_UP_APIC
513 bool "Local APIC support on uniprocessors"
514 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
515 help
516 A local APIC (Advanced Programmable Interrupt Controller) is an
517 integrated interrupt controller in the CPU. If you have a single-CPU
518 system which has a processor with a local APIC, you can say Y here to
519 enable and use it. If you say Y here even though your machine doesn't
520 have a local APIC, then the kernel will still run with no slowdown at
521 all. The local APIC supports CPU-generated self-interrupts (timer,
522 performance counters), and the NMI watchdog which detects hard
523 lockups.
525 config X86_UP_IOAPIC
526 bool "IO-APIC support on uniprocessors"
527 depends on X86_UP_APIC
528 help
529 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
530 SMP-capable replacement for PC-style interrupt controllers. Most
531 SMP systems and many recent uniprocessor systems have one.
533 If you have a single-CPU system with an IO-APIC, you can say Y here
534 to use it. If you say Y here even though your machine doesn't have
535 an IO-APIC, then the kernel will still run with no slowdown at all.
537 config X86_LOCAL_APIC
538 def_bool y
539 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
541 config X86_IO_APIC
542 def_bool y
543 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
545 config X86_VISWS_APIC
546 def_bool y
547 depends on X86_32 && X86_VISWS
549 config X86_MCE
550 bool "Machine Check Exception"
551 depends on !X86_VOYAGER
552 ---help---
553 Machine Check Exception support allows the processor to notify the
554 kernel if it detects a problem (e.g. overheating, component failure).
555 The action the kernel takes depends on the severity of the problem,
556 ranging from a warning message on the console, to halting the machine.
557 Your processor must be a Pentium or newer to support this - check the
558 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
559 have a design flaw which leads to false MCE events - hence MCE is
560 disabled on all P5 processors, unless explicitly enabled with "mce"
561 as a boot argument. Similarly, if MCE is built in and creates a
562 problem on some new non-standard machine, you can boot with "nomce"
563 to disable it. MCE support simply ignores non-MCE processors like
564 the 386 and 486, so nearly everyone can say Y here.
566 config X86_MCE_INTEL
567 def_bool y
568 prompt "Intel MCE features"
569 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
570 help
571 Additional support for intel specific MCE features such as
572 the thermal monitor.
574 config X86_MCE_AMD
575 def_bool y
576 prompt "AMD MCE features"
577 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
578 help
579 Additional support for AMD specific MCE features such as
580 the DRAM Error Threshold.
582 config X86_MCE_NONFATAL
583 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
584 depends on X86_32 && X86_MCE
585 help
586 Enabling this feature starts a timer that triggers every 5 seconds which
587 will look at the machine check registers to see if anything happened.
588 Non-fatal problems automatically get corrected (but still logged).
589 Disable this if you don't want to see these messages.
590 Seeing the messages this option prints out may be indicative of dying
591 or out-of-spec (ie, overclocked) hardware.
592 This option only does something on certain CPUs.
593 (AMD Athlon/Duron and Intel Pentium 4)
595 config X86_MCE_P4THERMAL
596 bool "check for P4 thermal throttling interrupt."
597 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
598 help
599 Enabling this feature will cause a message to be printed when the P4
600 enters thermal throttling.
602 config VM86
603 bool "Enable VM86 support" if EMBEDDED
604 default y
605 depends on X86_32
606 help
607 This option is required by programs like DOSEMU to run 16-bit legacy
608 code on X86 processors. It also may be needed by software like
609 XFree86 to initialize some video cards via BIOS. Disabling this
610 option saves about 6k.
612 config TOSHIBA
613 tristate "Toshiba Laptop support"
614 depends on X86_32
615 ---help---
616 This adds a driver to safely access the System Management Mode of
617 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
618 not work on models with a Phoenix BIOS. The System Management Mode
619 is used to set the BIOS and power saving options on Toshiba portables.
621 For information on utilities to make use of this driver see the
622 Toshiba Linux utilities web site at:
623 <http://www.buzzard.org.uk/toshiba/>.
625 Say Y if you intend to run this kernel on a Toshiba portable.
626 Say N otherwise.
628 config I8K
629 tristate "Dell laptop support"
630 depends on X86_32
631 ---help---
632 This adds a driver to safely access the System Management Mode
633 of the CPU on the Dell Inspiron 8000. The System Management Mode
634 is used to read cpu temperature and cooling fan status and to
635 control the fans on the I8K portables.
637 This driver has been tested only on the Inspiron 8000 but it may
638 also work with other Dell laptops. You can force loading on other
639 models by passing the parameter `force=1' to the module. Use at
640 your own risk.
642 For information on utilities to make use of this driver see the
643 I8K Linux utilities web site at:
644 <http://people.debian.org/~dz/i8k/>
646 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
647 Say N otherwise.
649 config X86_REBOOTFIXUPS
650 def_bool n
651 prompt "Enable X86 board specific fixups for reboot"
652 depends on X86_32 && X86
653 ---help---
654 This enables chipset and/or board specific fixups to be done
655 in order to get reboot to work correctly. This is only needed on
656 some combinations of hardware and BIOS. The symptom, for which
657 this config is intended, is when reboot ends with a stalled/hung
658 system.
660 Currently, the only fixup is for the Geode machines using
661 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
663 Say Y if you want to enable the fixup. Currently, it's safe to
664 enable this option even if you don't need it.
665 Say N otherwise.
667 config MICROCODE
668 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
669 select FW_LOADER
670 ---help---
671 If you say Y here, you will be able to update the microcode on
672 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
673 Pentium III, Pentium 4, Xeon etc. You will obviously need the
674 actual microcode binary data itself which is not shipped with the
675 Linux kernel.
677 For latest news and information on obtaining all the required
678 ingredients for this driver, check:
679 <http://www.urbanmyth.org/microcode/>.
681 To compile this driver as a module, choose M here: the
682 module will be called microcode.
684 config MICROCODE_OLD_INTERFACE
685 def_bool y
686 depends on MICROCODE
688 config X86_MSR
689 tristate "/dev/cpu/*/msr - Model-specific register support"
690 help
691 This device gives privileged processes access to the x86
692 Model-Specific Registers (MSRs). It is a character device with
693 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
694 MSR accesses are directed to a specific CPU on multi-processor
695 systems.
697 config X86_CPUID
698 tristate "/dev/cpu/*/cpuid - CPU information support"
699 help
700 This device gives processes access to the x86 CPUID instruction to
701 be executed on a specific processor. It is a character device
702 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
703 /dev/cpu/31/cpuid.
705 choice
706 prompt "High Memory Support"
707 default HIGHMEM4G if !X86_NUMAQ
708 default HIGHMEM64G if X86_NUMAQ
709 depends on X86_32
711 config NOHIGHMEM
712 bool "off"
713 depends on !X86_NUMAQ
714 ---help---
715 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
716 However, the address space of 32-bit x86 processors is only 4
717 Gigabytes large. That means that, if you have a large amount of
718 physical memory, not all of it can be "permanently mapped" by the
719 kernel. The physical memory that's not permanently mapped is called
720 "high memory".
722 If you are compiling a kernel which will never run on a machine with
723 more than 1 Gigabyte total physical RAM, answer "off" here (default
724 choice and suitable for most users). This will result in a "3GB/1GB"
725 split: 3GB are mapped so that each process sees a 3GB virtual memory
726 space and the remaining part of the 4GB virtual memory space is used
727 by the kernel to permanently map as much physical memory as
728 possible.
730 If the machine has between 1 and 4 Gigabytes physical RAM, then
731 answer "4GB" here.
733 If more than 4 Gigabytes is used then answer "64GB" here. This
734 selection turns Intel PAE (Physical Address Extension) mode on.
735 PAE implements 3-level paging on IA32 processors. PAE is fully
736 supported by Linux, PAE mode is implemented on all recent Intel
737 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
738 then the kernel will not boot on CPUs that don't support PAE!
740 The actual amount of total physical memory will either be
741 auto detected or can be forced by using a kernel command line option
742 such as "mem=256M". (Try "man bootparam" or see the documentation of
743 your boot loader (lilo or loadlin) about how to pass options to the
744 kernel at boot time.)
746 If unsure, say "off".
748 config HIGHMEM4G
749 bool "4GB"
750 depends on !X86_NUMAQ
751 help
752 Select this if you have a 32-bit processor and between 1 and 4
753 gigabytes of physical RAM.
755 config HIGHMEM64G
756 bool "64GB"
757 depends on !M386 && !M486
758 select X86_PAE
759 help
760 Select this if you have a 32-bit processor and more than 4
761 gigabytes of physical RAM.
763 endchoice
765 choice
766 depends on EXPERIMENTAL
767 prompt "Memory split" if EMBEDDED
768 default VMSPLIT_3G
769 depends on X86_32
770 help
771 Select the desired split between kernel and user memory.
773 If the address range available to the kernel is less than the
774 physical memory installed, the remaining memory will be available
775 as "high memory". Accessing high memory is a little more costly
776 than low memory, as it needs to be mapped into the kernel first.
777 Note that increasing the kernel address space limits the range
778 available to user programs, making the address space there
779 tighter. Selecting anything other than the default 3G/1G split
780 will also likely make your kernel incompatible with binary-only
781 kernel modules.
783 If you are not absolutely sure what you are doing, leave this
784 option alone!
786 config VMSPLIT_3G
787 bool "3G/1G user/kernel split"
788 config VMSPLIT_3G_OPT
789 depends on !X86_PAE
790 bool "3G/1G user/kernel split (for full 1G low memory)"
791 config VMSPLIT_2G
792 bool "2G/2G user/kernel split"
793 config VMSPLIT_2G_OPT
794 depends on !X86_PAE
795 bool "2G/2G user/kernel split (for full 2G low memory)"
796 config VMSPLIT_1G
797 bool "1G/3G user/kernel split"
798 endchoice
800 config PAGE_OFFSET
801 hex
802 default 0xB0000000 if VMSPLIT_3G_OPT
803 default 0x80000000 if VMSPLIT_2G
804 default 0x78000000 if VMSPLIT_2G_OPT
805 default 0x40000000 if VMSPLIT_1G
806 default 0xC0000000
807 depends on X86_32
809 config HIGHMEM
810 def_bool y
811 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
813 config X86_PAE
814 def_bool n
815 prompt "PAE (Physical Address Extension) Support"
816 depends on X86_32 && !HIGHMEM4G
817 select RESOURCES_64BIT
818 help
819 PAE is required for NX support, and furthermore enables
820 larger swapspace support for non-overcommit purposes. It
821 has the cost of more pagetable lookup overhead, and also
822 consumes more pagetable space per process.
824 # Common NUMA Features
825 config NUMA
826 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
827 depends on SMP
828 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
829 default n if X86_PC
830 default y if (X86_NUMAQ || X86_SUMMIT)
831 help
832 Enable NUMA (Non Uniform Memory Access) support.
833 The kernel will try to allocate memory used by a CPU on the
834 local memory controller of the CPU and add some more
835 NUMA awareness to the kernel.
837 For i386 this is currently highly experimental and should be only
838 used for kernel development. It might also cause boot failures.
839 For x86_64 this is recommended on all multiprocessor Opteron systems.
840 If the system is EM64T, you should say N unless your system is
841 EM64T NUMA.
843 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
844 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
846 config K8_NUMA
847 def_bool y
848 prompt "Old style AMD Opteron NUMA detection"
849 depends on X86_64 && NUMA && PCI
850 help
851 Enable K8 NUMA node topology detection. You should say Y here if
852 you have a multi processor AMD K8 system. This uses an old
853 method to read the NUMA configuration directly from the builtin
854 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
855 instead, which also takes priority if both are compiled in.
857 config X86_64_ACPI_NUMA
858 def_bool y
859 prompt "ACPI NUMA detection"
860 depends on X86_64 && NUMA && ACPI && PCI
861 select ACPI_NUMA
862 help
863 Enable ACPI SRAT based node topology detection.
865 config NUMA_EMU
866 bool "NUMA emulation"
867 depends on X86_64 && NUMA
868 help
869 Enable NUMA emulation. A flat machine will be split
870 into virtual nodes when booted with "numa=fake=N", where N is the
871 number of nodes. This is only useful for debugging.
873 config NODES_SHIFT
874 int
875 range 1 15 if X86_64
876 default "6" if X86_64
877 default "4" if X86_NUMAQ
878 default "3"
879 depends on NEED_MULTIPLE_NODES
881 config HAVE_ARCH_BOOTMEM_NODE
882 def_bool y
883 depends on X86_32 && NUMA
885 config ARCH_HAVE_MEMORY_PRESENT
886 def_bool y
887 depends on X86_32 && DISCONTIGMEM
889 config NEED_NODE_MEMMAP_SIZE
890 def_bool y
891 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
893 config HAVE_ARCH_ALLOC_REMAP
894 def_bool y
895 depends on X86_32 && NUMA
897 config ARCH_FLATMEM_ENABLE
898 def_bool y
899 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
901 config ARCH_DISCONTIGMEM_ENABLE
902 def_bool y
903 depends on NUMA && X86_32
905 config ARCH_DISCONTIGMEM_DEFAULT
906 def_bool y
907 depends on NUMA && X86_32
909 config ARCH_SPARSEMEM_DEFAULT
910 def_bool y
911 depends on X86_64
913 config ARCH_SPARSEMEM_ENABLE
914 def_bool y
915 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
916 select SPARSEMEM_STATIC if X86_32
917 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
919 config ARCH_SELECT_MEMORY_MODEL
920 def_bool y
921 depends on ARCH_SPARSEMEM_ENABLE
923 config ARCH_MEMORY_PROBE
924 def_bool X86_64
925 depends on MEMORY_HOTPLUG
927 source "mm/Kconfig"
929 config HIGHPTE
930 bool "Allocate 3rd-level pagetables from highmem"
931 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
932 help
933 The VM uses one page table entry for each page of physical memory.
934 For systems with a lot of RAM, this can be wasteful of precious
935 low memory. Setting this option will put user-space page table
936 entries in high memory.
938 config MATH_EMULATION
939 bool
940 prompt "Math emulation" if X86_32
941 ---help---
942 Linux can emulate a math coprocessor (used for floating point
943 operations) if you don't have one. 486DX and Pentium processors have
944 a math coprocessor built in, 486SX and 386 do not, unless you added
945 a 487DX or 387, respectively. (The messages during boot time can
946 give you some hints here ["man dmesg"].) Everyone needs either a
947 coprocessor or this emulation.
949 If you don't have a math coprocessor, you need to say Y here; if you
950 say Y here even though you have a coprocessor, the coprocessor will
951 be used nevertheless. (This behavior can be changed with the kernel
952 command line option "no387", which comes handy if your coprocessor
953 is broken. Try "man bootparam" or see the documentation of your boot
954 loader (lilo or loadlin) about how to pass options to the kernel at
955 boot time.) This means that it is a good idea to say Y here if you
956 intend to use this kernel on different machines.
958 More information about the internals of the Linux math coprocessor
959 emulation can be found in <file:arch/x86/math-emu/README>.
961 If you are not sure, say Y; apart from resulting in a 66 KB bigger
962 kernel, it won't hurt.
964 config MTRR
965 bool "MTRR (Memory Type Range Register) support"
966 ---help---
967 On Intel P6 family processors (Pentium Pro, Pentium II and later)
968 the Memory Type Range Registers (MTRRs) may be used to control
969 processor access to memory ranges. This is most useful if you have
970 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
971 allows bus write transfers to be combined into a larger transfer
972 before bursting over the PCI/AGP bus. This can increase performance
973 of image write operations 2.5 times or more. Saying Y here creates a
974 /proc/mtrr file which may be used to manipulate your processor's
975 MTRRs. Typically the X server should use this.
977 This code has a reasonably generic interface so that similar
978 control registers on other processors can be easily supported
979 as well:
981 The Cyrix 6x86, 6x86MX and M II processors have Address Range
982 Registers (ARRs) which provide a similar functionality to MTRRs. For
983 these, the ARRs are used to emulate the MTRRs.
984 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
985 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
986 write-combining. All of these processors are supported by this code
987 and it makes sense to say Y here if you have one of them.
989 Saying Y here also fixes a problem with buggy SMP BIOSes which only
990 set the MTRRs for the boot CPU and not for the secondary CPUs. This
991 can lead to all sorts of problems, so it's good to say Y here.
993 You can safely say Y even if your machine doesn't have MTRRs, you'll
994 just add about 9 KB to your kernel.
996 See <file:Documentation/mtrr.txt> for more information.
998 config EFI
999 def_bool n
1000 prompt "EFI runtime service support"
1001 depends on ACPI
1002 ---help---
1003 This enables the kernel to use EFI runtime services that are
1004 available (such as the EFI variable services).
1006 This option is only useful on systems that have EFI firmware.
1007 In addition, you should use the latest ELILO loader available
1008 at <http://elilo.sourceforge.net> in order to take advantage
1009 of EFI runtime services. However, even with this option, the
1010 resultant kernel should continue to boot on existing non-EFI
1011 platforms.
1013 config IRQBALANCE
1014 def_bool y
1015 prompt "Enable kernel irq balancing"
1016 depends on X86_32 && SMP && X86_IO_APIC
1017 help
1018 The default yes will allow the kernel to do irq load balancing.
1019 Saying no will keep the kernel from doing irq load balancing.
1021 config SECCOMP
1022 def_bool y
1023 prompt "Enable seccomp to safely compute untrusted bytecode"
1024 depends on PROC_FS
1025 help
1026 This kernel feature is useful for number crunching applications
1027 that may need to compute untrusted bytecode during their
1028 execution. By using pipes or other transports made available to
1029 the process as file descriptors supporting the read/write
1030 syscalls, it's possible to isolate those applications in
1031 their own address space using seccomp. Once seccomp is
1032 enabled via /proc/<pid>/seccomp, it cannot be disabled
1033 and the task is only allowed to execute a few safe syscalls
1034 defined by each seccomp mode.
1036 If unsure, say Y. Only embedded should say N here.
1038 config CC_STACKPROTECTOR
1039 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1040 depends on X86_64 && EXPERIMENTAL
1041 help
1042 This option turns on the -fstack-protector GCC feature. This
1043 feature puts, at the beginning of critical functions, a canary
1044 value on the stack just before the return address, and validates
1045 the value just before actually returning. Stack based buffer
1046 overflows (that need to overwrite this return address) now also
1047 overwrite the canary, which gets detected and the attack is then
1048 neutralized via a kernel panic.
1050 This feature requires gcc version 4.2 or above, or a distribution
1051 gcc with the feature backported. Older versions are automatically
1052 detected and for those versions, this configuration option is ignored.
1054 config CC_STACKPROTECTOR_ALL
1055 bool "Use stack-protector for all functions"
1056 depends on CC_STACKPROTECTOR
1057 help
1058 Normally, GCC only inserts the canary value protection for
1059 functions that use large-ish on-stack buffers. By enabling
1060 this option, GCC will be asked to do this for ALL functions.
1062 source kernel/Kconfig.hz
1064 config KEXEC
1065 bool "kexec system call"
1066 help
1067 kexec is a system call that implements the ability to shutdown your
1068 current kernel, and to start another kernel. It is like a reboot
1069 but it is independent of the system firmware. And like a reboot
1070 you can start any kernel with it, not just Linux.
1072 The name comes from the similarity to the exec system call.
1074 It is an ongoing process to be certain the hardware in a machine
1075 is properly shutdown, so do not be surprised if this code does not
1076 initially work for you. It may help to enable device hotplugging
1077 support. As of this writing the exact hardware interface is
1078 strongly in flux, so no good recommendation can be made.
1080 config CRASH_DUMP
1081 bool "kernel crash dumps (EXPERIMENTAL)"
1082 depends on EXPERIMENTAL
1083 depends on X86_64 || (X86_32 && HIGHMEM)
1084 help
1085 Generate crash dump after being started by kexec.
1086 This should be normally only set in special crash dump kernels
1087 which are loaded in the main kernel with kexec-tools into
1088 a specially reserved region and then later executed after
1089 a crash by kdump/kexec. The crash dump kernel must be compiled
1090 to a memory address not used by the main kernel or BIOS using
1091 PHYSICAL_START, or it must be built as a relocatable image
1092 (CONFIG_RELOCATABLE=y).
1093 For more details see Documentation/kdump/kdump.txt
1095 config PHYSICAL_START
1096 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1097 default "0x1000000" if X86_NUMAQ
1098 default "0x200000" if X86_64
1099 default "0x100000"
1100 help
1101 This gives the physical address where the kernel is loaded.
1103 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1104 bzImage will decompress itself to above physical address and
1105 run from there. Otherwise, bzImage will run from the address where
1106 it has been loaded by the boot loader and will ignore above physical
1107 address.
1109 In normal kdump cases one does not have to set/change this option
1110 as now bzImage can be compiled as a completely relocatable image
1111 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1112 address. This option is mainly useful for the folks who don't want
1113 to use a bzImage for capturing the crash dump and want to use a
1114 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1115 to be specifically compiled to run from a specific memory area
1116 (normally a reserved region) and this option comes handy.
1118 So if you are using bzImage for capturing the crash dump, leave
1119 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1120 Otherwise if you plan to use vmlinux for capturing the crash dump
1121 change this value to start of the reserved region (Typically 16MB
1122 0x1000000). In other words, it can be set based on the "X" value as
1123 specified in the "crashkernel=YM@XM" command line boot parameter
1124 passed to the panic-ed kernel. Typically this parameter is set as
1125 crashkernel=64M@16M. Please take a look at
1126 Documentation/kdump/kdump.txt for more details about crash dumps.
1128 Usage of bzImage for capturing the crash dump is recommended as
1129 one does not have to build two kernels. Same kernel can be used
1130 as production kernel and capture kernel. Above option should have
1131 gone away after relocatable bzImage support is introduced. But it
1132 is present because there are users out there who continue to use
1133 vmlinux for dump capture. This option should go away down the
1134 line.
1136 Don't change this unless you know what you are doing.
1138 config RELOCATABLE
1139 bool "Build a relocatable kernel (EXPERIMENTAL)"
1140 depends on EXPERIMENTAL
1141 help
1142 This builds a kernel image that retains relocation information
1143 so it can be loaded someplace besides the default 1MB.
1144 The relocations tend to make the kernel binary about 10% larger,
1145 but are discarded at runtime.
1147 One use is for the kexec on panic case where the recovery kernel
1148 must live at a different physical address than the primary
1149 kernel.
1151 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1152 it has been loaded at and the compile time physical address
1153 (CONFIG_PHYSICAL_START) is ignored.
1155 config PHYSICAL_ALIGN
1156 hex
1157 prompt "Alignment value to which kernel should be aligned" if X86_32
1158 default "0x100000" if X86_32
1159 default "0x200000" if X86_64
1160 range 0x2000 0x400000
1161 help
1162 This value puts the alignment restrictions on physical address
1163 where kernel is loaded and run from. Kernel is compiled for an
1164 address which meets above alignment restriction.
1166 If bootloader loads the kernel at a non-aligned address and
1167 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1168 address aligned to above value and run from there.
1170 If bootloader loads the kernel at a non-aligned address and
1171 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1172 load address and decompress itself to the address it has been
1173 compiled for and run from there. The address for which kernel is
1174 compiled already meets above alignment restrictions. Hence the
1175 end result is that kernel runs from a physical address meeting
1176 above alignment restrictions.
1178 Don't change this unless you know what you are doing.
1180 config HOTPLUG_CPU
1181 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1182 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1183 ---help---
1184 Say Y here to experiment with turning CPUs off and on, and to
1185 enable suspend on SMP systems. CPUs can be controlled through
1186 /sys/devices/system/cpu.
1187 Say N if you want to disable CPU hotplug and don't need to
1188 suspend.
1190 config COMPAT_VDSO
1191 def_bool y
1192 prompt "Compat VDSO support"
1193 depends on X86_32 || IA32_EMULATION
1194 help
1195 Map the 32-bit VDSO to the predictable old-style address too.
1196 ---help---
1197 Say N here if you are running a sufficiently recent glibc
1198 version (2.3.3 or later), to remove the high-mapped
1199 VDSO mapping and to exclusively use the randomized VDSO.
1201 If unsure, say Y.
1203 endmenu
1205 config ARCH_ENABLE_MEMORY_HOTPLUG
1206 def_bool y
1207 depends on X86_64 || (X86_32 && HIGHMEM)
1209 config HAVE_ARCH_EARLY_PFN_TO_NID
1210 def_bool X86_64
1211 depends on NUMA
1213 menu "Power management options"
1214 depends on !X86_VOYAGER
1216 config ARCH_HIBERNATION_HEADER
1217 def_bool y
1218 depends on X86_64 && HIBERNATION
1220 source "kernel/power/Kconfig"
1222 source "drivers/acpi/Kconfig"
1224 config X86_APM_BOOT
1225 bool
1226 default y
1227 depends on APM || APM_MODULE
1229 menuconfig APM
1230 tristate "APM (Advanced Power Management) BIOS support"
1231 depends on X86_32 && PM_SLEEP && !X86_VISWS
1232 ---help---
1233 APM is a BIOS specification for saving power using several different
1234 techniques. This is mostly useful for battery powered laptops with
1235 APM compliant BIOSes. If you say Y here, the system time will be
1236 reset after a RESUME operation, the /proc/apm device will provide
1237 battery status information, and user-space programs will receive
1238 notification of APM "events" (e.g. battery status change).
1240 If you select "Y" here, you can disable actual use of the APM
1241 BIOS by passing the "apm=off" option to the kernel at boot time.
1243 Note that the APM support is almost completely disabled for
1244 machines with more than one CPU.
1246 In order to use APM, you will need supporting software. For location
1247 and more information, read <file:Documentation/pm.txt> and the
1248 Battery Powered Linux mini-HOWTO, available from
1249 <http://www.tldp.org/docs.html#howto>.
1251 This driver does not spin down disk drives (see the hdparm(8)
1252 manpage ("man 8 hdparm") for that), and it doesn't turn off
1253 VESA-compliant "green" monitors.
1255 This driver does not support the TI 4000M TravelMate and the ACER
1256 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1257 desktop machines also don't have compliant BIOSes, and this driver
1258 may cause those machines to panic during the boot phase.
1260 Generally, if you don't have a battery in your machine, there isn't
1261 much point in using this driver and you should say N. If you get
1262 random kernel OOPSes or reboots that don't seem to be related to
1263 anything, try disabling/enabling this option (or disabling/enabling
1264 APM in your BIOS).
1266 Some other things you should try when experiencing seemingly random,
1267 "weird" problems:
1269 1) make sure that you have enough swap space and that it is
1270 enabled.
1271 2) pass the "no-hlt" option to the kernel
1272 3) switch on floating point emulation in the kernel and pass
1273 the "no387" option to the kernel
1274 4) pass the "floppy=nodma" option to the kernel
1275 5) pass the "mem=4M" option to the kernel (thereby disabling
1276 all but the first 4 MB of RAM)
1277 6) make sure that the CPU is not over clocked.
1278 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1279 8) disable the cache from your BIOS settings
1280 9) install a fan for the video card or exchange video RAM
1281 10) install a better fan for the CPU
1282 11) exchange RAM chips
1283 12) exchange the motherboard.
1285 To compile this driver as a module, choose M here: the
1286 module will be called apm.
1288 if APM
1290 config APM_IGNORE_USER_SUSPEND
1291 bool "Ignore USER SUSPEND"
1292 help
1293 This option will ignore USER SUSPEND requests. On machines with a
1294 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1295 series notebooks, it is necessary to say Y because of a BIOS bug.
1297 config APM_DO_ENABLE
1298 bool "Enable PM at boot time"
1299 ---help---
1300 Enable APM features at boot time. From page 36 of the APM BIOS
1301 specification: "When disabled, the APM BIOS does not automatically
1302 power manage devices, enter the Standby State, enter the Suspend
1303 State, or take power saving steps in response to CPU Idle calls."
1304 This driver will make CPU Idle calls when Linux is idle (unless this
1305 feature is turned off -- see "Do CPU IDLE calls", below). This
1306 should always save battery power, but more complicated APM features
1307 will be dependent on your BIOS implementation. You may need to turn
1308 this option off if your computer hangs at boot time when using APM
1309 support, or if it beeps continuously instead of suspending. Turn
1310 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1311 T400CDT. This is off by default since most machines do fine without
1312 this feature.
1314 config APM_CPU_IDLE
1315 bool "Make CPU Idle calls when idle"
1316 help
1317 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1318 On some machines, this can activate improved power savings, such as
1319 a slowed CPU clock rate, when the machine is idle. These idle calls
1320 are made after the idle loop has run for some length of time (e.g.,
1321 333 mS). On some machines, this will cause a hang at boot time or
1322 whenever the CPU becomes idle. (On machines with more than one CPU,
1323 this option does nothing.)
1325 config APM_DISPLAY_BLANK
1326 bool "Enable console blanking using APM"
1327 help
1328 Enable console blanking using the APM. Some laptops can use this to
1329 turn off the LCD backlight when the screen blanker of the Linux
1330 virtual console blanks the screen. Note that this is only used by
1331 the virtual console screen blanker, and won't turn off the backlight
1332 when using the X Window system. This also doesn't have anything to
1333 do with your VESA-compliant power-saving monitor. Further, this
1334 option doesn't work for all laptops -- it might not turn off your
1335 backlight at all, or it might print a lot of errors to the console,
1336 especially if you are using gpm.
1338 config APM_ALLOW_INTS
1339 bool "Allow interrupts during APM BIOS calls"
1340 help
1341 Normally we disable external interrupts while we are making calls to
1342 the APM BIOS as a measure to lessen the effects of a badly behaving
1343 BIOS implementation. The BIOS should reenable interrupts if it
1344 needs to. Unfortunately, some BIOSes do not -- especially those in
1345 many of the newer IBM Thinkpads. If you experience hangs when you
1346 suspend, try setting this to Y. Otherwise, say N.
1348 config APM_REAL_MODE_POWER_OFF
1349 bool "Use real mode APM BIOS call to power off"
1350 help
1351 Use real mode APM BIOS calls to switch off the computer. This is
1352 a work-around for a number of buggy BIOSes. Switch this option on if
1353 your computer crashes instead of powering off properly.
1355 endif # APM
1357 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1359 source "drivers/cpuidle/Kconfig"
1361 endmenu
1364 menu "Bus options (PCI etc.)"
1366 config PCI
1367 bool "PCI support" if !X86_VISWS
1368 depends on !X86_VOYAGER
1369 default y
1370 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1371 help
1372 Find out whether you have a PCI motherboard. PCI is the name of a
1373 bus system, i.e. the way the CPU talks to the other stuff inside
1374 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1375 VESA. If you have PCI, say Y, otherwise N.
1377 choice
1378 prompt "PCI access mode"
1379 depends on X86_32 && PCI && !X86_VISWS
1380 default PCI_GOANY
1381 ---help---
1382 On PCI systems, the BIOS can be used to detect the PCI devices and
1383 determine their configuration. However, some old PCI motherboards
1384 have BIOS bugs and may crash if this is done. Also, some embedded
1385 PCI-based systems don't have any BIOS at all. Linux can also try to
1386 detect the PCI hardware directly without using the BIOS.
1388 With this option, you can specify how Linux should detect the
1389 PCI devices. If you choose "BIOS", the BIOS will be used,
1390 if you choose "Direct", the BIOS won't be used, and if you
1391 choose "MMConfig", then PCI Express MMCONFIG will be used.
1392 If you choose "Any", the kernel will try MMCONFIG, then the
1393 direct access method and falls back to the BIOS if that doesn't
1394 work. If unsure, go with the default, which is "Any".
1396 config PCI_GOBIOS
1397 bool "BIOS"
1399 config PCI_GOMMCONFIG
1400 bool "MMConfig"
1402 config PCI_GODIRECT
1403 bool "Direct"
1405 config PCI_GOANY
1406 bool "Any"
1408 endchoice
1410 config PCI_BIOS
1411 def_bool y
1412 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1414 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1415 config PCI_DIRECT
1416 def_bool y
1417 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1419 config PCI_MMCONFIG
1420 def_bool y
1421 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1423 config PCI_DOMAINS
1424 def_bool y
1425 depends on PCI
1427 config PCI_MMCONFIG
1428 bool "Support mmconfig PCI config space access"
1429 depends on X86_64 && PCI && ACPI
1431 config DMAR
1432 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1433 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1434 help
1435 DMA remapping (DMAR) devices support enables independent address
1436 translations for Direct Memory Access (DMA) from devices.
1437 These DMA remapping devices are reported via ACPI tables
1438 and include PCI device scope covered by these DMA
1439 remapping devices.
1441 config DMAR_GFX_WA
1442 def_bool y
1443 prompt "Support for Graphics workaround"
1444 depends on DMAR
1445 help
1446 Current Graphics drivers tend to use physical address
1447 for DMA and avoid using DMA APIs. Setting this config
1448 option permits the IOMMU driver to set a unity map for
1449 all the OS-visible memory. Hence the driver can continue
1450 to use physical addresses for DMA.
1452 config DMAR_FLOPPY_WA
1453 def_bool y
1454 depends on DMAR
1455 help
1456 Floppy disk drivers are know to bypass DMA API calls
1457 thereby failing to work when IOMMU is enabled. This
1458 workaround will setup a 1:1 mapping for the first
1459 16M to make floppy (an ISA device) work.
1461 source "drivers/pci/pcie/Kconfig"
1463 source "drivers/pci/Kconfig"
1465 # x86_64 have no ISA slots, but do have ISA-style DMA.
1466 config ISA_DMA_API
1467 def_bool y
1469 if X86_32
1471 config ISA
1472 bool "ISA support"
1473 depends on !(X86_VOYAGER || X86_VISWS)
1474 help
1475 Find out whether you have ISA slots on your motherboard. ISA is the
1476 name of a bus system, i.e. the way the CPU talks to the other stuff
1477 inside your box. Other bus systems are PCI, EISA, MicroChannel
1478 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1479 newer boards don't support it. If you have ISA, say Y, otherwise N.
1481 config EISA
1482 bool "EISA support"
1483 depends on ISA
1484 ---help---
1485 The Extended Industry Standard Architecture (EISA) bus was
1486 developed as an open alternative to the IBM MicroChannel bus.
1488 The EISA bus provided some of the features of the IBM MicroChannel
1489 bus while maintaining backward compatibility with cards made for
1490 the older ISA bus. The EISA bus saw limited use between 1988 and
1491 1995 when it was made obsolete by the PCI bus.
1493 Say Y here if you are building a kernel for an EISA-based machine.
1495 Otherwise, say N.
1497 source "drivers/eisa/Kconfig"
1499 config MCA
1500 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1501 default y if X86_VOYAGER
1502 help
1503 MicroChannel Architecture is found in some IBM PS/2 machines and
1504 laptops. It is a bus system similar to PCI or ISA. See
1505 <file:Documentation/mca.txt> (and especially the web page given
1506 there) before attempting to build an MCA bus kernel.
1508 source "drivers/mca/Kconfig"
1510 config SCx200
1511 tristate "NatSemi SCx200 support"
1512 depends on !X86_VOYAGER
1513 help
1514 This provides basic support for National Semiconductor's
1515 (now AMD's) Geode processors. The driver probes for the
1516 PCI-IDs of several on-chip devices, so its a good dependency
1517 for other scx200_* drivers.
1519 If compiled as a module, the driver is named scx200.
1521 config SCx200HR_TIMER
1522 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1523 depends on SCx200 && GENERIC_TIME
1524 default y
1525 help
1526 This driver provides a clocksource built upon the on-chip
1527 27MHz high-resolution timer. Its also a workaround for
1528 NSC Geode SC-1100's buggy TSC, which loses time when the
1529 processor goes idle (as is done by the scheduler). The
1530 other workaround is idle=poll boot option.
1532 config GEODE_MFGPT_TIMER
1533 def_bool y
1534 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1535 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1536 help
1537 This driver provides a clock event source based on the MFGPT
1538 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1539 MFGPTs have a better resolution and max interval than the
1540 generic PIT, and are suitable for use as high-res timers.
1542 endif # X86_32
1544 config K8_NB
1545 def_bool y
1546 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1548 source "drivers/pcmcia/Kconfig"
1550 source "drivers/pci/hotplug/Kconfig"
1552 endmenu
1555 menu "Executable file formats / Emulations"
1557 source "fs/Kconfig.binfmt"
1559 config IA32_EMULATION
1560 bool "IA32 Emulation"
1561 depends on X86_64
1562 select COMPAT_BINFMT_ELF
1563 help
1564 Include code to run 32-bit programs under a 64-bit kernel. You should
1565 likely turn this on, unless you're 100% sure that you don't have any
1566 32-bit programs left.
1568 config IA32_AOUT
1569 tristate "IA32 a.out support"
1570 depends on IA32_EMULATION
1571 help
1572 Support old a.out binaries in the 32bit emulation.
1574 config COMPAT
1575 def_bool y
1576 depends on IA32_EMULATION
1578 config COMPAT_FOR_U64_ALIGNMENT
1579 def_bool COMPAT
1580 depends on X86_64
1582 config SYSVIPC_COMPAT
1583 def_bool y
1584 depends on X86_64 && COMPAT && SYSVIPC
1586 endmenu
1589 source "net/Kconfig"
1591 source "drivers/Kconfig"
1593 source "drivers/firmware/Kconfig"
1595 source "fs/Kconfig"
1597 source "kernel/Kconfig.instrumentation"
1599 source "arch/x86/Kconfig.debug"
1601 source "security/Kconfig"
1603 source "crypto/Kconfig"
1605 source "arch/x86/kvm/Kconfig"
1607 source "lib/Kconfig"