2 mainmenu "Linux Kernel Configuration for x86"
6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
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
21 select HAVE_UNSTABLE_SCHED_CLOCK
25 select HAVE_KRETPROBES
27 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
28 select HAVE_ARCH_KGDB if !X86_VOYAGER
34 default "arch/x86/configs/i386_defconfig"
40 default "arch/x86/configs/x86_64_defconfig"
43 config GENERIC_LOCKBREAK
49 config GENERIC_CMOS_UPDATE
52 config CLOCKSOURCE_WATCHDOG
55 config GENERIC_CLOCKEVENTS
58 config GENERIC_CLOCKEVENTS_BROADCAST
60 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
62 config LOCKDEP_SUPPORT
65 config STACKTRACE_SUPPORT
68 config HAVE_LATENCYTOP_SUPPORT
71 config FAST_CMPXCHG_LOCAL
84 config GENERIC_ISA_DMA
94 config GENERIC_HWEIGHT
100 config ARCH_MAY_HAVE_PC_FDC
103 config RWSEM_GENERIC_SPINLOCK
106 config RWSEM_XCHGADD_ALGORITHM
109 config ARCH_HAS_ILOG2_U32
112 config ARCH_HAS_ILOG2_U64
115 config ARCH_HAS_CPU_IDLE_WAIT
118 config GENERIC_CALIBRATE_DELAY
121 config GENERIC_TIME_VSYSCALL
125 config ARCH_HAS_CPU_RELAX
128 config ARCH_HAS_CACHE_LINE_SIZE
131 config HAVE_SETUP_PER_CPU_AREA
132 def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
134 config HAVE_CPUMASK_OF_CPU_MAP
137 config ARCH_HIBERNATION_POSSIBLE
139 depends on !SMP || !X86_VOYAGER
141 config ARCH_SUSPEND_POSSIBLE
143 depends on !X86_VOYAGER
149 config ARCH_POPULATES_NODE_MAP
156 config ARCH_SUPPORTS_AOUT
159 config ARCH_SUPPORTS_OPTIMIZED_INLINING
162 # Use the generic interrupt handling code in kernel/irq/:
163 config GENERIC_HARDIRQS
167 config GENERIC_IRQ_PROBE
171 config GENERIC_PENDING_IRQ
173 depends on GENERIC_HARDIRQS && SMP
178 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
183 depends on X86_32 && SMP
187 depends on X86_64 && SMP
192 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
195 config X86_BIOS_REBOOT
197 depends on !X86_VISWS && !X86_VOYAGER
200 config X86_TRAMPOLINE
202 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
207 source "init/Kconfig"
209 menu "Processor type and features"
211 source "kernel/time/Kconfig"
214 bool "Symmetric multi-processing support"
216 This enables support for systems with more than one CPU. If you have
217 a system with only one CPU, like most personal computers, say N. If
218 you have a system with more than one CPU, say Y.
220 If you say N here, the kernel will run on single and multiprocessor
221 machines, but will use only one CPU of a multiprocessor machine. If
222 you say Y here, the kernel will run on many, but not all,
223 singleprocessor machines. On a singleprocessor machine, the kernel
224 will run faster if you say N here.
226 Note that if you say Y here and choose architecture "586" or
227 "Pentium" under "Processor family", the kernel will not work on 486
228 architectures. Similarly, multiprocessor kernels for the "PPro"
229 architecture may not work on all Pentium based boards.
231 People using multiprocessor machines who say Y here should also say
232 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
233 Management" code will be disabled if you say Y here.
235 See also <file:Documentation/i386/IO-APIC.txt>,
236 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
237 <http://www.tldp.org/docs.html#howto>.
239 If you don't know what to do here, say N.
242 prompt "Subarchitecture Type"
248 Choose this option if your computer is a standard PC or compatible.
254 Select this for an AMD Elan processor.
256 Do not use this option for K6/Athlon/Opteron processors!
258 If unsure, choose "PC-compatible" instead.
262 depends on X86_32 && (SMP || BROKEN)
264 Voyager is an MCA-based 32-way capable SMP architecture proprietary
265 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
269 If you do not specifically know you have a Voyager based machine,
270 say N here, otherwise the kernel you build will not be bootable.
273 bool "NUMAQ (IBM/Sequent)"
274 depends on SMP && X86_32
277 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
278 multiquad box. This changes the way that processors are bootstrapped,
279 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
280 You will need a new lynxer.elf file to flash your firmware with - send
281 email to <Martin.Bligh@us.ibm.com>.
284 bool "Summit/EXA (IBM x440)"
285 depends on X86_32 && SMP
287 This option is needed for IBM systems that use the Summit/EXA chipset.
288 In particular, it is needed for the x440.
290 If you don't have one of these computers, you should say N here.
291 If you want to build a NUMA kernel, you must select ACPI.
294 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
295 depends on X86_32 && SMP
297 This option is needed for the systems that have more than 8 CPUs
298 and if the system is not of any sub-arch type above.
300 If you don't have such a system, you should say N here.
303 bool "SGI 320/540 (Visual Workstation)"
306 The SGI Visual Workstation series is an IA32-based workstation
307 based on SGI systems chips with some legacy PC hardware attached.
309 Say Y here to create a kernel to run on the SGI 320 or 540.
311 A kernel compiled for the Visual Workstation will not run on PCs
312 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
314 config X86_GENERICARCH
315 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
318 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
319 It is intended for a generic binary kernel.
320 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
323 bool "Support for Unisys ES7000 IA32 series"
324 depends on X86_32 && SMP
326 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
327 supposed to run on an IA32-based Unisys ES7000 system.
328 Only choose this option if you have such a system, otherwise you
332 bool "RDC R-321x SoC"
335 select X86_REBOOTFIXUPS
341 This option is needed for RDC R-321x system-on-chip, also known
343 If you don't have one of these chips, you should say N here.
346 bool "Support for ScaleMP vSMP"
350 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
351 supposed to run on these EM64T-based machines. Only choose this option
352 if you have one of these machines.
356 config SCHED_NO_NO_OMIT_FRAME_POINTER
358 prompt "Single-depth WCHAN output"
361 Calculate simpler /proc/<PID>/wchan values. If this option
362 is disabled then wchan values will recurse back to the
363 caller function. This provides more accurate wchan values,
364 at the expense of slightly more scheduling overhead.
366 If in doubt, say "Y".
368 menuconfig PARAVIRT_GUEST
369 bool "Paravirtualized guest support"
371 Say Y here to get to see options related to running Linux under
372 various hypervisors. This option alone does not add any kernel code.
374 If you say N, all options in this submenu will be skipped and disabled.
378 source "arch/x86/xen/Kconfig"
381 bool "VMI Guest support"
384 depends on !(X86_VISWS || X86_VOYAGER)
386 VMI provides a paravirtualized interface to the VMware ESX server
387 (it could be used by other hypervisors in theory too, but is not
388 at the moment), by linking the kernel to a GPL-ed ROM module
389 provided by the hypervisor.
392 bool "KVM paravirtualized clock"
394 depends on !(X86_VISWS || X86_VOYAGER)
396 Turning on this option will allow you to run a paravirtualized clock
397 when running over the KVM hypervisor. Instead of relying on a PIT
398 (or probably other) emulation by the underlying device model, the host
399 provides the guest with timing infrastructure such as time of day, and
403 bool "KVM Guest support"
405 depends on !(X86_VISWS || X86_VOYAGER)
407 This option enables various optimizations for running under the KVM
410 source "arch/x86/lguest/Kconfig"
413 bool "Enable paravirtualization code"
414 depends on !(X86_VISWS || X86_VOYAGER)
416 This changes the kernel so it can modify itself when it is run
417 under a hypervisor, potentially improving performance significantly
418 over full virtualization. However, when run without a hypervisor
419 the kernel is theoretically slower and slightly larger.
423 config MEMTEST_BOOTPARAM
424 bool "Memtest boot parameter"
428 This option adds a kernel parameter 'memtest', which allows memtest
429 to be disabled at boot. If this option is selected, memtest
430 functionality can be disabled with memtest=0 on the kernel
431 command line. The purpose of this option is to allow a single
432 kernel image to be distributed with memtest built in, but not
435 If you are unsure how to answer this question, answer Y.
437 config MEMTEST_BOOTPARAM_VALUE
438 int "Memtest boot parameter default value (0-4)"
439 depends on MEMTEST_BOOTPARAM
443 This option sets the default value for the kernel parameter
444 'memtest', which allows memtest to be disabled at boot. If this
445 option is set to 0 (zero), the memtest kernel parameter will
446 default to 0, disabling memtest at bootup. If this option is
447 set to 4, the memtest kernel parameter will default to 4,
448 enabling memtest at bootup, and use that as pattern number.
450 If you are unsure how to answer this question, answer 0.
454 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
457 config HAVE_ARCH_PARSE_SRAT
461 config X86_SUMMIT_NUMA
463 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
465 config X86_CYCLONE_TIMER
467 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
469 config ES7000_CLUSTERED_APIC
471 depends on SMP && X86_ES7000 && MPENTIUMIII
473 source "arch/x86/Kconfig.cpu"
477 prompt "HPET Timer Support" if X86_32
479 Use the IA-PC HPET (High Precision Event Timer) to manage
480 time in preference to the PIT and RTC, if a HPET is
482 HPET is the next generation timer replacing legacy 8254s.
483 The HPET provides a stable time base on SMP
484 systems, unlike the TSC, but it is more expensive to access,
485 as it is off-chip. You can find the HPET spec at
486 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
488 You can safely choose Y here. However, HPET will only be
489 activated if the platform and the BIOS support this feature.
490 Otherwise the 8254 will be used for timing services.
492 Choose N to continue using the legacy 8254 timer.
494 config HPET_EMULATE_RTC
496 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
498 # Mark as embedded because too many people got it wrong.
499 # The code disables itself when not needed.
502 bool "Enable DMI scanning" if EMBEDDED
504 Enabled scanning of DMI to identify machine quirks. Say Y
505 here unless you have verified that your setup is not
506 affected by entries in the DMI blacklist. Required by PNP
510 bool "GART IOMMU support" if EMBEDDED
514 depends on X86_64 && PCI
516 Support for full DMA access of devices with 32bit memory access only
517 on systems with more than 3GB. This is usually needed for USB,
518 sound, many IDE/SATA chipsets and some other devices.
519 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
520 based hardware IOMMU and a software bounce buffer based IOMMU used
521 on Intel systems and as fallback.
522 The code is only active when needed (enough memory and limited
523 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
527 bool "IBM Calgary IOMMU support"
529 depends on X86_64 && PCI && EXPERIMENTAL
531 Support for hardware IOMMUs in IBM's xSeries x366 and x460
532 systems. Needed to run systems with more than 3GB of memory
533 properly with 32-bit PCI devices that do not support DAC
534 (Double Address Cycle). Calgary also supports bus level
535 isolation, where all DMAs pass through the IOMMU. This
536 prevents them from going anywhere except their intended
537 destination. This catches hard-to-find kernel bugs and
538 mis-behaving drivers and devices that do not use the DMA-API
539 properly to set up their DMA buffers. The IOMMU can be
540 turned off at boot time with the iommu=off parameter.
541 Normally the kernel will make the right choice by itself.
544 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
546 prompt "Should Calgary be enabled by default?"
547 depends on CALGARY_IOMMU
549 Should Calgary be enabled by default? if you choose 'y', Calgary
550 will be used (if it exists). If you choose 'n', Calgary will not be
551 used even if it exists. If you choose 'n' and would like to use
552 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
555 # need this always selected by IOMMU for the VIA workaround
559 Support for software bounce buffers used on x86-64 systems
560 which don't have a hardware IOMMU (e.g. the current generation
561 of Intel's x86-64 CPUs). Using this PCI devices which can only
562 access 32-bits of memory can be used on systems with more than
563 3 GB of memory. If unsure, say Y.
566 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
569 int "Maximum number of CPUs (2-255)"
572 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
575 This allows you to specify the maximum number of CPUs which this
576 kernel will support. The maximum supported value is 255 and the
577 minimum value which makes sense is 2.
579 This is purely to save memory - each supported CPU adds
580 approximately eight kilobytes to the kernel image.
583 bool "SMT (Hyperthreading) scheduler support"
586 SMT scheduler support improves the CPU scheduler's decision making
587 when dealing with Intel Pentium 4 chips with HyperThreading at a
588 cost of slightly increased overhead in some places. If unsure say
593 prompt "Multi-core scheduler support"
596 Multi-core scheduler support improves the CPU scheduler's decision
597 making when dealing with multi-core CPU chips at a cost of slightly
598 increased overhead in some places. If unsure say N here.
600 source "kernel/Kconfig.preempt"
603 bool "Local APIC support on uniprocessors"
604 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
606 A local APIC (Advanced Programmable Interrupt Controller) is an
607 integrated interrupt controller in the CPU. If you have a single-CPU
608 system which has a processor with a local APIC, you can say Y here to
609 enable and use it. If you say Y here even though your machine doesn't
610 have a local APIC, then the kernel will still run with no slowdown at
611 all. The local APIC supports CPU-generated self-interrupts (timer,
612 performance counters), and the NMI watchdog which detects hard
616 bool "IO-APIC support on uniprocessors"
617 depends on X86_UP_APIC
619 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
620 SMP-capable replacement for PC-style interrupt controllers. Most
621 SMP systems and many recent uniprocessor systems have one.
623 If you have a single-CPU system with an IO-APIC, you can say Y here
624 to use it. If you say Y here even though your machine doesn't have
625 an IO-APIC, then the kernel will still run with no slowdown at all.
627 config X86_LOCAL_APIC
629 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
633 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
635 config X86_VISWS_APIC
637 depends on X86_32 && X86_VISWS
640 bool "Machine Check Exception"
641 depends on !X86_VOYAGER
643 Machine Check Exception support allows the processor to notify the
644 kernel if it detects a problem (e.g. overheating, component failure).
645 The action the kernel takes depends on the severity of the problem,
646 ranging from a warning message on the console, to halting the machine.
647 Your processor must be a Pentium or newer to support this - check the
648 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
649 have a design flaw which leads to false MCE events - hence MCE is
650 disabled on all P5 processors, unless explicitly enabled with "mce"
651 as a boot argument. Similarly, if MCE is built in and creates a
652 problem on some new non-standard machine, you can boot with "nomce"
653 to disable it. MCE support simply ignores non-MCE processors like
654 the 386 and 486, so nearly everyone can say Y here.
658 prompt "Intel MCE features"
659 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
661 Additional support for intel specific MCE features such as
666 prompt "AMD MCE features"
667 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
669 Additional support for AMD specific MCE features such as
670 the DRAM Error Threshold.
672 config X86_MCE_NONFATAL
673 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
674 depends on X86_32 && X86_MCE
676 Enabling this feature starts a timer that triggers every 5 seconds which
677 will look at the machine check registers to see if anything happened.
678 Non-fatal problems automatically get corrected (but still logged).
679 Disable this if you don't want to see these messages.
680 Seeing the messages this option prints out may be indicative of dying
681 or out-of-spec (ie, overclocked) hardware.
682 This option only does something on certain CPUs.
683 (AMD Athlon/Duron and Intel Pentium 4)
685 config X86_MCE_P4THERMAL
686 bool "check for P4 thermal throttling interrupt."
687 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
689 Enabling this feature will cause a message to be printed when the P4
690 enters thermal throttling.
693 bool "Enable VM86 support" if EMBEDDED
697 This option is required by programs like DOSEMU to run 16-bit legacy
698 code on X86 processors. It also may be needed by software like
699 XFree86 to initialize some video cards via BIOS. Disabling this
700 option saves about 6k.
703 tristate "Toshiba Laptop support"
706 This adds a driver to safely access the System Management Mode of
707 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
708 not work on models with a Phoenix BIOS. The System Management Mode
709 is used to set the BIOS and power saving options on Toshiba portables.
711 For information on utilities to make use of this driver see the
712 Toshiba Linux utilities web site at:
713 <http://www.buzzard.org.uk/toshiba/>.
715 Say Y if you intend to run this kernel on a Toshiba portable.
719 tristate "Dell laptop support"
721 This adds a driver to safely access the System Management Mode
722 of the CPU on the Dell Inspiron 8000. The System Management Mode
723 is used to read cpu temperature and cooling fan status and to
724 control the fans on the I8K portables.
726 This driver has been tested only on the Inspiron 8000 but it may
727 also work with other Dell laptops. You can force loading on other
728 models by passing the parameter `force=1' to the module. Use at
731 For information on utilities to make use of this driver see the
732 I8K Linux utilities web site at:
733 <http://people.debian.org/~dz/i8k/>
735 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
738 config X86_REBOOTFIXUPS
740 prompt "Enable X86 board specific fixups for reboot"
741 depends on X86_32 && X86
743 This enables chipset and/or board specific fixups to be done
744 in order to get reboot to work correctly. This is only needed on
745 some combinations of hardware and BIOS. The symptom, for which
746 this config is intended, is when reboot ends with a stalled/hung
749 Currently, the only fixup is for the Geode machines using
750 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
752 Say Y if you want to enable the fixup. Currently, it's safe to
753 enable this option even if you don't need it.
757 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
760 If you say Y here, you will be able to update the microcode on
761 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
762 Pentium III, Pentium 4, Xeon etc. You will obviously need the
763 actual microcode binary data itself which is not shipped with the
766 For latest news and information on obtaining all the required
767 ingredients for this driver, check:
768 <http://www.urbanmyth.org/microcode/>.
770 To compile this driver as a module, choose M here: the
771 module will be called microcode.
773 config MICROCODE_OLD_INTERFACE
778 tristate "/dev/cpu/*/msr - Model-specific register support"
780 This device gives privileged processes access to the x86
781 Model-Specific Registers (MSRs). It is a character device with
782 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
783 MSR accesses are directed to a specific CPU on multi-processor
787 tristate "/dev/cpu/*/cpuid - CPU information support"
789 This device gives processes access to the x86 CPUID instruction to
790 be executed on a specific processor. It is a character device
791 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
795 prompt "High Memory Support"
796 default HIGHMEM4G if !X86_NUMAQ
797 default HIGHMEM64G if X86_NUMAQ
802 depends on !X86_NUMAQ
804 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
805 However, the address space of 32-bit x86 processors is only 4
806 Gigabytes large. That means that, if you have a large amount of
807 physical memory, not all of it can be "permanently mapped" by the
808 kernel. The physical memory that's not permanently mapped is called
811 If you are compiling a kernel which will never run on a machine with
812 more than 1 Gigabyte total physical RAM, answer "off" here (default
813 choice and suitable for most users). This will result in a "3GB/1GB"
814 split: 3GB are mapped so that each process sees a 3GB virtual memory
815 space and the remaining part of the 4GB virtual memory space is used
816 by the kernel to permanently map as much physical memory as
819 If the machine has between 1 and 4 Gigabytes physical RAM, then
822 If more than 4 Gigabytes is used then answer "64GB" here. This
823 selection turns Intel PAE (Physical Address Extension) mode on.
824 PAE implements 3-level paging on IA32 processors. PAE is fully
825 supported by Linux, PAE mode is implemented on all recent Intel
826 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
827 then the kernel will not boot on CPUs that don't support PAE!
829 The actual amount of total physical memory will either be
830 auto detected or can be forced by using a kernel command line option
831 such as "mem=256M". (Try "man bootparam" or see the documentation of
832 your boot loader (lilo or loadlin) about how to pass options to the
833 kernel at boot time.)
835 If unsure, say "off".
839 depends on !X86_NUMAQ
841 Select this if you have a 32-bit processor and between 1 and 4
842 gigabytes of physical RAM.
846 depends on !M386 && !M486
849 Select this if you have a 32-bit processor and more than 4
850 gigabytes of physical RAM.
855 depends on EXPERIMENTAL
856 prompt "Memory split" if EMBEDDED
860 Select the desired split between kernel and user memory.
862 If the address range available to the kernel is less than the
863 physical memory installed, the remaining memory will be available
864 as "high memory". Accessing high memory is a little more costly
865 than low memory, as it needs to be mapped into the kernel first.
866 Note that increasing the kernel address space limits the range
867 available to user programs, making the address space there
868 tighter. Selecting anything other than the default 3G/1G split
869 will also likely make your kernel incompatible with binary-only
872 If you are not absolutely sure what you are doing, leave this
876 bool "3G/1G user/kernel split"
877 config VMSPLIT_3G_OPT
879 bool "3G/1G user/kernel split (for full 1G low memory)"
881 bool "2G/2G user/kernel split"
882 config VMSPLIT_2G_OPT
884 bool "2G/2G user/kernel split (for full 2G low memory)"
886 bool "1G/3G user/kernel split"
891 default 0xB0000000 if VMSPLIT_3G_OPT
892 default 0x80000000 if VMSPLIT_2G
893 default 0x78000000 if VMSPLIT_2G_OPT
894 default 0x40000000 if VMSPLIT_1G
900 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
904 prompt "PAE (Physical Address Extension) Support"
905 depends on X86_32 && !HIGHMEM4G
906 select RESOURCES_64BIT
908 PAE is required for NX support, and furthermore enables
909 larger swapspace support for non-overcommit purposes. It
910 has the cost of more pagetable lookup overhead, and also
911 consumes more pagetable space per process.
913 # Common NUMA Features
915 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
917 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
919 default y if (X86_NUMAQ || X86_SUMMIT)
921 Enable NUMA (Non Uniform Memory Access) support.
922 The kernel will try to allocate memory used by a CPU on the
923 local memory controller of the CPU and add some more
924 NUMA awareness to the kernel.
926 For i386 this is currently highly experimental and should be only
927 used for kernel development. It might also cause boot failures.
928 For x86_64 this is recommended on all multiprocessor Opteron systems.
929 If the system is EM64T, you should say N unless your system is
932 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
933 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
937 prompt "Old style AMD Opteron NUMA detection"
938 depends on X86_64 && NUMA && PCI
940 Enable K8 NUMA node topology detection. You should say Y here if
941 you have a multi processor AMD K8 system. This uses an old
942 method to read the NUMA configuration directly from the builtin
943 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
944 instead, which also takes priority if both are compiled in.
946 config X86_64_ACPI_NUMA
948 prompt "ACPI NUMA detection"
949 depends on X86_64 && NUMA && ACPI && PCI
952 Enable ACPI SRAT based node topology detection.
954 # Some NUMA nodes have memory ranges that span
955 # other nodes. Even though a pfn is valid and
956 # between a node's start and end pfns, it may not
957 # reside on that node. See memmap_init_zone()
959 config NODES_SPAN_OTHER_NODES
961 depends on X86_64_ACPI_NUMA
964 bool "NUMA emulation"
965 depends on X86_64 && NUMA
967 Enable NUMA emulation. A flat machine will be split
968 into virtual nodes when booted with "numa=fake=N", where N is the
969 number of nodes. This is only useful for debugging.
972 int "Max num nodes shift(1-15)"
974 default "6" if X86_64
975 default "4" if X86_NUMAQ
977 depends on NEED_MULTIPLE_NODES
979 config HAVE_ARCH_BOOTMEM_NODE
981 depends on X86_32 && NUMA
983 config ARCH_HAVE_MEMORY_PRESENT
985 depends on X86_32 && DISCONTIGMEM
987 config NEED_NODE_MEMMAP_SIZE
989 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
991 config HAVE_ARCH_ALLOC_REMAP
993 depends on X86_32 && NUMA
995 config ARCH_FLATMEM_ENABLE
997 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
999 config ARCH_DISCONTIGMEM_ENABLE
1001 depends on NUMA && X86_32
1003 config ARCH_DISCONTIGMEM_DEFAULT
1005 depends on NUMA && X86_32
1007 config ARCH_SPARSEMEM_DEFAULT
1011 config ARCH_SPARSEMEM_ENABLE
1013 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1014 select SPARSEMEM_STATIC if X86_32
1015 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1017 config ARCH_SELECT_MEMORY_MODEL
1019 depends on ARCH_SPARSEMEM_ENABLE
1021 config ARCH_MEMORY_PROBE
1023 depends on MEMORY_HOTPLUG
1028 bool "Allocate 3rd-level pagetables from highmem"
1029 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1031 The VM uses one page table entry for each page of physical memory.
1032 For systems with a lot of RAM, this can be wasteful of precious
1033 low memory. Setting this option will put user-space page table
1034 entries in high memory.
1036 config MATH_EMULATION
1038 prompt "Math emulation" if X86_32
1040 Linux can emulate a math coprocessor (used for floating point
1041 operations) if you don't have one. 486DX and Pentium processors have
1042 a math coprocessor built in, 486SX and 386 do not, unless you added
1043 a 487DX or 387, respectively. (The messages during boot time can
1044 give you some hints here ["man dmesg"].) Everyone needs either a
1045 coprocessor or this emulation.
1047 If you don't have a math coprocessor, you need to say Y here; if you
1048 say Y here even though you have a coprocessor, the coprocessor will
1049 be used nevertheless. (This behavior can be changed with the kernel
1050 command line option "no387", which comes handy if your coprocessor
1051 is broken. Try "man bootparam" or see the documentation of your boot
1052 loader (lilo or loadlin) about how to pass options to the kernel at
1053 boot time.) This means that it is a good idea to say Y here if you
1054 intend to use this kernel on different machines.
1056 More information about the internals of the Linux math coprocessor
1057 emulation can be found in <file:arch/x86/math-emu/README>.
1059 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1060 kernel, it won't hurt.
1063 bool "MTRR (Memory Type Range Register) support"
1065 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1066 the Memory Type Range Registers (MTRRs) may be used to control
1067 processor access to memory ranges. This is most useful if you have
1068 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1069 allows bus write transfers to be combined into a larger transfer
1070 before bursting over the PCI/AGP bus. This can increase performance
1071 of image write operations 2.5 times or more. Saying Y here creates a
1072 /proc/mtrr file which may be used to manipulate your processor's
1073 MTRRs. Typically the X server should use this.
1075 This code has a reasonably generic interface so that similar
1076 control registers on other processors can be easily supported
1079 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1080 Registers (ARRs) which provide a similar functionality to MTRRs. For
1081 these, the ARRs are used to emulate the MTRRs.
1082 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1083 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1084 write-combining. All of these processors are supported by this code
1085 and it makes sense to say Y here if you have one of them.
1087 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1088 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1089 can lead to all sorts of problems, so it's good to say Y here.
1091 You can safely say Y even if your machine doesn't have MTRRs, you'll
1092 just add about 9 KB to your kernel.
1094 See <file:Documentation/mtrr.txt> for more information.
1098 prompt "x86 PAT support"
1101 Use PAT attributes to setup page level cache control.
1103 PATs are the modern equivalents of MTRRs and are much more
1104 flexible than MTRRs.
1106 Say N here if you see bootup problems (boot crash, boot hang,
1107 spontaneous reboots) or a non-working video driver.
1113 prompt "EFI runtime service support"
1116 This enables the kernel to use EFI runtime services that are
1117 available (such as the EFI variable services).
1119 This option is only useful on systems that have EFI firmware.
1120 In addition, you should use the latest ELILO loader available
1121 at <http://elilo.sourceforge.net> in order to take advantage
1122 of EFI runtime services. However, even with this option, the
1123 resultant kernel should continue to boot on existing non-EFI
1128 prompt "Enable kernel irq balancing"
1129 depends on X86_32 && SMP && X86_IO_APIC
1131 The default yes will allow the kernel to do irq load balancing.
1132 Saying no will keep the kernel from doing irq load balancing.
1136 prompt "Enable seccomp to safely compute untrusted bytecode"
1139 This kernel feature is useful for number crunching applications
1140 that may need to compute untrusted bytecode during their
1141 execution. By using pipes or other transports made available to
1142 the process as file descriptors supporting the read/write
1143 syscalls, it's possible to isolate those applications in
1144 their own address space using seccomp. Once seccomp is
1145 enabled via /proc/<pid>/seccomp, it cannot be disabled
1146 and the task is only allowed to execute a few safe syscalls
1147 defined by each seccomp mode.
1149 If unsure, say Y. Only embedded should say N here.
1151 config CC_STACKPROTECTOR
1152 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1153 depends on X86_64 && EXPERIMENTAL && BROKEN
1155 This option turns on the -fstack-protector GCC feature. This
1156 feature puts, at the beginning of critical functions, a canary
1157 value on the stack just before the return address, and validates
1158 the value just before actually returning. Stack based buffer
1159 overflows (that need to overwrite this return address) now also
1160 overwrite the canary, which gets detected and the attack is then
1161 neutralized via a kernel panic.
1163 This feature requires gcc version 4.2 or above, or a distribution
1164 gcc with the feature backported. Older versions are automatically
1165 detected and for those versions, this configuration option is ignored.
1167 config CC_STACKPROTECTOR_ALL
1168 bool "Use stack-protector for all functions"
1169 depends on CC_STACKPROTECTOR
1171 Normally, GCC only inserts the canary value protection for
1172 functions that use large-ish on-stack buffers. By enabling
1173 this option, GCC will be asked to do this for ALL functions.
1175 source kernel/Kconfig.hz
1178 bool "kexec system call"
1179 depends on X86_BIOS_REBOOT
1181 kexec is a system call that implements the ability to shutdown your
1182 current kernel, and to start another kernel. It is like a reboot
1183 but it is independent of the system firmware. And like a reboot
1184 you can start any kernel with it, not just Linux.
1186 The name comes from the similarity to the exec system call.
1188 It is an ongoing process to be certain the hardware in a machine
1189 is properly shutdown, so do not be surprised if this code does not
1190 initially work for you. It may help to enable device hotplugging
1191 support. As of this writing the exact hardware interface is
1192 strongly in flux, so no good recommendation can be made.
1195 bool "kernel crash dumps (EXPERIMENTAL)"
1196 depends on EXPERIMENTAL
1197 depends on X86_64 || (X86_32 && HIGHMEM)
1199 Generate crash dump after being started by kexec.
1200 This should be normally only set in special crash dump kernels
1201 which are loaded in the main kernel with kexec-tools into
1202 a specially reserved region and then later executed after
1203 a crash by kdump/kexec. The crash dump kernel must be compiled
1204 to a memory address not used by the main kernel or BIOS using
1205 PHYSICAL_START, or it must be built as a relocatable image
1206 (CONFIG_RELOCATABLE=y).
1207 For more details see Documentation/kdump/kdump.txt
1209 config PHYSICAL_START
1210 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1211 default "0x1000000" if X86_NUMAQ
1212 default "0x200000" if X86_64
1215 This gives the physical address where the kernel is loaded.
1217 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1218 bzImage will decompress itself to above physical address and
1219 run from there. Otherwise, bzImage will run from the address where
1220 it has been loaded by the boot loader and will ignore above physical
1223 In normal kdump cases one does not have to set/change this option
1224 as now bzImage can be compiled as a completely relocatable image
1225 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1226 address. This option is mainly useful for the folks who don't want
1227 to use a bzImage for capturing the crash dump and want to use a
1228 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1229 to be specifically compiled to run from a specific memory area
1230 (normally a reserved region) and this option comes handy.
1232 So if you are using bzImage for capturing the crash dump, leave
1233 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1234 Otherwise if you plan to use vmlinux for capturing the crash dump
1235 change this value to start of the reserved region (Typically 16MB
1236 0x1000000). In other words, it can be set based on the "X" value as
1237 specified in the "crashkernel=YM@XM" command line boot parameter
1238 passed to the panic-ed kernel. Typically this parameter is set as
1239 crashkernel=64M@16M. Please take a look at
1240 Documentation/kdump/kdump.txt for more details about crash dumps.
1242 Usage of bzImage for capturing the crash dump is recommended as
1243 one does not have to build two kernels. Same kernel can be used
1244 as production kernel and capture kernel. Above option should have
1245 gone away after relocatable bzImage support is introduced. But it
1246 is present because there are users out there who continue to use
1247 vmlinux for dump capture. This option should go away down the
1250 Don't change this unless you know what you are doing.
1253 bool "Build a relocatable kernel (EXPERIMENTAL)"
1254 depends on EXPERIMENTAL
1256 This builds a kernel image that retains relocation information
1257 so it can be loaded someplace besides the default 1MB.
1258 The relocations tend to make the kernel binary about 10% larger,
1259 but are discarded at runtime.
1261 One use is for the kexec on panic case where the recovery kernel
1262 must live at a different physical address than the primary
1265 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1266 it has been loaded at and the compile time physical address
1267 (CONFIG_PHYSICAL_START) is ignored.
1269 config PHYSICAL_ALIGN
1271 prompt "Alignment value to which kernel should be aligned" if X86_32
1272 default "0x100000" if X86_32
1273 default "0x200000" if X86_64
1274 range 0x2000 0x400000
1276 This value puts the alignment restrictions on physical address
1277 where kernel is loaded and run from. Kernel is compiled for an
1278 address which meets above alignment restriction.
1280 If bootloader loads the kernel at a non-aligned address and
1281 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1282 address aligned to above value and run from there.
1284 If bootloader loads the kernel at a non-aligned address and
1285 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1286 load address and decompress itself to the address it has been
1287 compiled for and run from there. The address for which kernel is
1288 compiled already meets above alignment restrictions. Hence the
1289 end result is that kernel runs from a physical address meeting
1290 above alignment restrictions.
1292 Don't change this unless you know what you are doing.
1295 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1296 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1298 Say Y here to experiment with turning CPUs off and on, and to
1299 enable suspend on SMP systems. CPUs can be controlled through
1300 /sys/devices/system/cpu.
1301 Say N if you want to disable CPU hotplug and don't need to
1306 prompt "Compat VDSO support"
1307 depends on X86_32 || IA32_EMULATION
1309 Map the 32-bit VDSO to the predictable old-style address too.
1311 Say N here if you are running a sufficiently recent glibc
1312 version (2.3.3 or later), to remove the high-mapped
1313 VDSO mapping and to exclusively use the randomized VDSO.
1319 config ARCH_ENABLE_MEMORY_HOTPLUG
1321 depends on X86_64 || (X86_32 && HIGHMEM)
1323 config HAVE_ARCH_EARLY_PFN_TO_NID
1327 menu "Power management options"
1328 depends on !X86_VOYAGER
1330 config ARCH_HIBERNATION_HEADER
1332 depends on X86_64 && HIBERNATION
1334 source "kernel/power/Kconfig"
1336 source "drivers/acpi/Kconfig"
1341 depends on APM || APM_MODULE
1344 tristate "APM (Advanced Power Management) BIOS support"
1345 depends on X86_32 && PM_SLEEP && !X86_VISWS
1347 APM is a BIOS specification for saving power using several different
1348 techniques. This is mostly useful for battery powered laptops with
1349 APM compliant BIOSes. If you say Y here, the system time will be
1350 reset after a RESUME operation, the /proc/apm device will provide
1351 battery status information, and user-space programs will receive
1352 notification of APM "events" (e.g. battery status change).
1354 If you select "Y" here, you can disable actual use of the APM
1355 BIOS by passing the "apm=off" option to the kernel at boot time.
1357 Note that the APM support is almost completely disabled for
1358 machines with more than one CPU.
1360 In order to use APM, you will need supporting software. For location
1361 and more information, read <file:Documentation/power/pm.txt> and the
1362 Battery Powered Linux mini-HOWTO, available from
1363 <http://www.tldp.org/docs.html#howto>.
1365 This driver does not spin down disk drives (see the hdparm(8)
1366 manpage ("man 8 hdparm") for that), and it doesn't turn off
1367 VESA-compliant "green" monitors.
1369 This driver does not support the TI 4000M TravelMate and the ACER
1370 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1371 desktop machines also don't have compliant BIOSes, and this driver
1372 may cause those machines to panic during the boot phase.
1374 Generally, if you don't have a battery in your machine, there isn't
1375 much point in using this driver and you should say N. If you get
1376 random kernel OOPSes or reboots that don't seem to be related to
1377 anything, try disabling/enabling this option (or disabling/enabling
1380 Some other things you should try when experiencing seemingly random,
1383 1) make sure that you have enough swap space and that it is
1385 2) pass the "no-hlt" option to the kernel
1386 3) switch on floating point emulation in the kernel and pass
1387 the "no387" option to the kernel
1388 4) pass the "floppy=nodma" option to the kernel
1389 5) pass the "mem=4M" option to the kernel (thereby disabling
1390 all but the first 4 MB of RAM)
1391 6) make sure that the CPU is not over clocked.
1392 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1393 8) disable the cache from your BIOS settings
1394 9) install a fan for the video card or exchange video RAM
1395 10) install a better fan for the CPU
1396 11) exchange RAM chips
1397 12) exchange the motherboard.
1399 To compile this driver as a module, choose M here: the
1400 module will be called apm.
1404 config APM_IGNORE_USER_SUSPEND
1405 bool "Ignore USER SUSPEND"
1407 This option will ignore USER SUSPEND requests. On machines with a
1408 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1409 series notebooks, it is necessary to say Y because of a BIOS bug.
1411 config APM_DO_ENABLE
1412 bool "Enable PM at boot time"
1414 Enable APM features at boot time. From page 36 of the APM BIOS
1415 specification: "When disabled, the APM BIOS does not automatically
1416 power manage devices, enter the Standby State, enter the Suspend
1417 State, or take power saving steps in response to CPU Idle calls."
1418 This driver will make CPU Idle calls when Linux is idle (unless this
1419 feature is turned off -- see "Do CPU IDLE calls", below). This
1420 should always save battery power, but more complicated APM features
1421 will be dependent on your BIOS implementation. You may need to turn
1422 this option off if your computer hangs at boot time when using APM
1423 support, or if it beeps continuously instead of suspending. Turn
1424 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1425 T400CDT. This is off by default since most machines do fine without
1429 bool "Make CPU Idle calls when idle"
1431 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1432 On some machines, this can activate improved power savings, such as
1433 a slowed CPU clock rate, when the machine is idle. These idle calls
1434 are made after the idle loop has run for some length of time (e.g.,
1435 333 mS). On some machines, this will cause a hang at boot time or
1436 whenever the CPU becomes idle. (On machines with more than one CPU,
1437 this option does nothing.)
1439 config APM_DISPLAY_BLANK
1440 bool "Enable console blanking using APM"
1442 Enable console blanking using the APM. Some laptops can use this to
1443 turn off the LCD backlight when the screen blanker of the Linux
1444 virtual console blanks the screen. Note that this is only used by
1445 the virtual console screen blanker, and won't turn off the backlight
1446 when using the X Window system. This also doesn't have anything to
1447 do with your VESA-compliant power-saving monitor. Further, this
1448 option doesn't work for all laptops -- it might not turn off your
1449 backlight at all, or it might print a lot of errors to the console,
1450 especially if you are using gpm.
1452 config APM_ALLOW_INTS
1453 bool "Allow interrupts during APM BIOS calls"
1455 Normally we disable external interrupts while we are making calls to
1456 the APM BIOS as a measure to lessen the effects of a badly behaving
1457 BIOS implementation. The BIOS should reenable interrupts if it
1458 needs to. Unfortunately, some BIOSes do not -- especially those in
1459 many of the newer IBM Thinkpads. If you experience hangs when you
1460 suspend, try setting this to Y. Otherwise, say N.
1462 config APM_REAL_MODE_POWER_OFF
1463 bool "Use real mode APM BIOS call to power off"
1465 Use real mode APM BIOS calls to switch off the computer. This is
1466 a work-around for a number of buggy BIOSes. Switch this option on if
1467 your computer crashes instead of powering off properly.
1471 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1473 source "drivers/cpuidle/Kconfig"
1478 menu "Bus options (PCI etc.)"
1481 bool "PCI support" if !X86_VISWS && !X86_VSMP
1482 depends on !X86_VOYAGER
1484 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1486 Find out whether you have a PCI motherboard. PCI is the name of a
1487 bus system, i.e. the way the CPU talks to the other stuff inside
1488 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1489 VESA. If you have PCI, say Y, otherwise N.
1492 prompt "PCI access mode"
1493 depends on X86_32 && PCI && !X86_VISWS
1496 On PCI systems, the BIOS can be used to detect the PCI devices and
1497 determine their configuration. However, some old PCI motherboards
1498 have BIOS bugs and may crash if this is done. Also, some embedded
1499 PCI-based systems don't have any BIOS at all. Linux can also try to
1500 detect the PCI hardware directly without using the BIOS.
1502 With this option, you can specify how Linux should detect the
1503 PCI devices. If you choose "BIOS", the BIOS will be used,
1504 if you choose "Direct", the BIOS won't be used, and if you
1505 choose "MMConfig", then PCI Express MMCONFIG will be used.
1506 If you choose "Any", the kernel will try MMCONFIG, then the
1507 direct access method and falls back to the BIOS if that doesn't
1508 work. If unsure, go with the default, which is "Any".
1513 config PCI_GOMMCONFIG
1530 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1532 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1535 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
1539 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1543 depends on PCI && PCI_GOOLPC
1551 bool "Support mmconfig PCI config space access"
1552 depends on X86_64 && PCI && ACPI
1555 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1556 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1558 DMA remapping (DMAR) devices support enables independent address
1559 translations for Direct Memory Access (DMA) from devices.
1560 These DMA remapping devices are reported via ACPI tables
1561 and include PCI device scope covered by these DMA
1566 prompt "Support for Graphics workaround"
1569 Current Graphics drivers tend to use physical address
1570 for DMA and avoid using DMA APIs. Setting this config
1571 option permits the IOMMU driver to set a unity map for
1572 all the OS-visible memory. Hence the driver can continue
1573 to use physical addresses for DMA.
1575 config DMAR_FLOPPY_WA
1579 Floppy disk drivers are know to bypass DMA API calls
1580 thereby failing to work when IOMMU is enabled. This
1581 workaround will setup a 1:1 mapping for the first
1582 16M to make floppy (an ISA device) work.
1584 source "drivers/pci/pcie/Kconfig"
1586 source "drivers/pci/Kconfig"
1588 # x86_64 have no ISA slots, but do have ISA-style DMA.
1596 depends on !(X86_VOYAGER || X86_VISWS)
1598 Find out whether you have ISA slots on your motherboard. ISA is the
1599 name of a bus system, i.e. the way the CPU talks to the other stuff
1600 inside your box. Other bus systems are PCI, EISA, MicroChannel
1601 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1602 newer boards don't support it. If you have ISA, say Y, otherwise N.
1608 The Extended Industry Standard Architecture (EISA) bus was
1609 developed as an open alternative to the IBM MicroChannel bus.
1611 The EISA bus provided some of the features of the IBM MicroChannel
1612 bus while maintaining backward compatibility with cards made for
1613 the older ISA bus. The EISA bus saw limited use between 1988 and
1614 1995 when it was made obsolete by the PCI bus.
1616 Say Y here if you are building a kernel for an EISA-based machine.
1620 source "drivers/eisa/Kconfig"
1623 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1624 default y if X86_VOYAGER
1626 MicroChannel Architecture is found in some IBM PS/2 machines and
1627 laptops. It is a bus system similar to PCI or ISA. See
1628 <file:Documentation/mca.txt> (and especially the web page given
1629 there) before attempting to build an MCA bus kernel.
1631 source "drivers/mca/Kconfig"
1634 tristate "NatSemi SCx200 support"
1635 depends on !X86_VOYAGER
1637 This provides basic support for National Semiconductor's
1638 (now AMD's) Geode processors. The driver probes for the
1639 PCI-IDs of several on-chip devices, so its a good dependency
1640 for other scx200_* drivers.
1642 If compiled as a module, the driver is named scx200.
1644 config SCx200HR_TIMER
1645 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1646 depends on SCx200 && GENERIC_TIME
1649 This driver provides a clocksource built upon the on-chip
1650 27MHz high-resolution timer. Its also a workaround for
1651 NSC Geode SC-1100's buggy TSC, which loses time when the
1652 processor goes idle (as is done by the scheduler). The
1653 other workaround is idle=poll boot option.
1655 config GEODE_MFGPT_TIMER
1657 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1658 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1660 This driver provides a clock event source based on the MFGPT
1661 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1662 MFGPTs have a better resolution and max interval than the
1663 generic PIT, and are suitable for use as high-res timers.
1666 bool "One Laptop Per Child support"
1669 Add support for detecting the unique features of the OLPC
1676 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1678 source "drivers/pcmcia/Kconfig"
1680 source "drivers/pci/hotplug/Kconfig"
1685 menu "Executable file formats / Emulations"
1687 source "fs/Kconfig.binfmt"
1689 config IA32_EMULATION
1690 bool "IA32 Emulation"
1692 select COMPAT_BINFMT_ELF
1694 Include code to run 32-bit programs under a 64-bit kernel. You should
1695 likely turn this on, unless you're 100% sure that you don't have any
1696 32-bit programs left.
1699 tristate "IA32 a.out support"
1700 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1702 Support old a.out binaries in the 32bit emulation.
1706 depends on IA32_EMULATION
1708 config COMPAT_FOR_U64_ALIGNMENT
1712 config SYSVIPC_COMPAT
1714 depends on X86_64 && COMPAT && SYSVIPC
1719 source "net/Kconfig"
1721 source "drivers/Kconfig"
1723 source "drivers/firmware/Kconfig"
1727 source "arch/x86/Kconfig.debug"
1729 source "security/Kconfig"
1731 source "crypto/Kconfig"
1733 source "arch/x86/kvm/Kconfig"
1735 source "lib/Kconfig"