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
26 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
27 select HAVE_ARCH_KGDB if !X86_VOYAGER
31 default "arch/x86/configs/i386_defconfig" if X86_32
32 default "arch/x86/configs/x86_64_defconfig" if X86_64
35 config GENERIC_LOCKBREAK
41 config GENERIC_CMOS_UPDATE
44 config CLOCKSOURCE_WATCHDOG
47 config GENERIC_CLOCKEVENTS
50 config GENERIC_CLOCKEVENTS_BROADCAST
52 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
54 config LOCKDEP_SUPPORT
57 config STACKTRACE_SUPPORT
60 config HAVE_LATENCYTOP_SUPPORT
63 config FAST_CMPXCHG_LOCAL
76 config GENERIC_ISA_DMA
86 config GENERIC_HWEIGHT
92 config ARCH_MAY_HAVE_PC_FDC
95 config RWSEM_GENERIC_SPINLOCK
98 config RWSEM_XCHGADD_ALGORITHM
101 config ARCH_HAS_ILOG2_U32
104 config ARCH_HAS_ILOG2_U64
107 config ARCH_HAS_CPU_IDLE_WAIT
110 config GENERIC_CALIBRATE_DELAY
113 config GENERIC_TIME_VSYSCALL
117 config ARCH_HAS_CPU_RELAX
120 config ARCH_HAS_CACHE_LINE_SIZE
123 config HAVE_SETUP_PER_CPU_AREA
124 def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
126 config HAVE_CPUMASK_OF_CPU_MAP
129 config ARCH_HIBERNATION_POSSIBLE
131 depends on !SMP || !X86_VOYAGER
133 config ARCH_SUSPEND_POSSIBLE
135 depends on !X86_VOYAGER
141 config ARCH_POPULATES_NODE_MAP
148 config ARCH_SUPPORTS_AOUT
151 config ARCH_SUPPORTS_OPTIMIZED_INLINING
154 # Use the generic interrupt handling code in kernel/irq/:
155 config GENERIC_HARDIRQS
159 config GENERIC_IRQ_PROBE
163 config GENERIC_PENDING_IRQ
165 depends on GENERIC_HARDIRQS && SMP
170 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
175 depends on X86_32 && SMP
179 depends on X86_64 && SMP
184 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
187 config X86_BIOS_REBOOT
189 depends on !X86_VISWS && !X86_VOYAGER
192 config X86_TRAMPOLINE
194 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
199 source "init/Kconfig"
201 menu "Processor type and features"
203 source "kernel/time/Kconfig"
206 bool "Symmetric multi-processing support"
208 This enables support for systems with more than one CPU. If you have
209 a system with only one CPU, like most personal computers, say N. If
210 you have a system with more than one CPU, say Y.
212 If you say N here, the kernel will run on single and multiprocessor
213 machines, but will use only one CPU of a multiprocessor machine. If
214 you say Y here, the kernel will run on many, but not all,
215 singleprocessor machines. On a singleprocessor machine, the kernel
216 will run faster if you say N here.
218 Note that if you say Y here and choose architecture "586" or
219 "Pentium" under "Processor family", the kernel will not work on 486
220 architectures. Similarly, multiprocessor kernels for the "PPro"
221 architecture may not work on all Pentium based boards.
223 People using multiprocessor machines who say Y here should also say
224 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
225 Management" code will be disabled if you say Y here.
227 See also <file:Documentation/i386/IO-APIC.txt>,
228 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
229 <http://www.tldp.org/docs.html#howto>.
231 If you don't know what to do here, say N.
234 prompt "Subarchitecture Type"
240 Choose this option if your computer is a standard PC or compatible.
246 Select this for an AMD Elan processor.
248 Do not use this option for K6/Athlon/Opteron processors!
250 If unsure, choose "PC-compatible" instead.
254 depends on X86_32 && (SMP || BROKEN) && !PCI
256 Voyager is an MCA-based 32-way capable SMP architecture proprietary
257 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
261 If you do not specifically know you have a Voyager based machine,
262 say N here, otherwise the kernel you build will not be bootable.
265 bool "NUMAQ (IBM/Sequent)"
266 depends on SMP && X86_32 && PCI
269 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
270 multiquad box. This changes the way that processors are bootstrapped,
271 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
272 You will need a new lynxer.elf file to flash your firmware with - send
273 email to <Martin.Bligh@us.ibm.com>.
276 bool "Summit/EXA (IBM x440)"
277 depends on X86_32 && SMP
279 This option is needed for IBM systems that use the Summit/EXA chipset.
280 In particular, it is needed for the x440.
282 If you don't have one of these computers, you should say N here.
283 If you want to build a NUMA kernel, you must select ACPI.
286 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
287 depends on X86_32 && SMP
289 This option is needed for the systems that have more than 8 CPUs
290 and if the system is not of any sub-arch type above.
292 If you don't have such a system, you should say N here.
295 bool "SGI 320/540 (Visual Workstation)"
296 depends on X86_32 && !PCI
298 The SGI Visual Workstation series is an IA32-based workstation
299 based on SGI systems chips with some legacy PC hardware attached.
301 Say Y here to create a kernel to run on the SGI 320 or 540.
303 A kernel compiled for the Visual Workstation will not run on PCs
304 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
306 config X86_GENERICARCH
307 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
310 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
311 It is intended for a generic binary kernel.
312 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
315 bool "Support for Unisys ES7000 IA32 series"
316 depends on X86_32 && SMP
318 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
319 supposed to run on an IA32-based Unisys ES7000 system.
320 Only choose this option if you have such a system, otherwise you
324 bool "RDC R-321x SoC"
327 select X86_REBOOTFIXUPS
333 This option is needed for RDC R-321x system-on-chip, also known
335 If you don't have one of these chips, you should say N here.
338 bool "Support for ScaleMP vSMP"
340 depends on X86_64 && !PCI
342 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
343 supposed to run on these EM64T-based machines. Only choose this option
344 if you have one of these machines.
348 config SCHED_NO_NO_OMIT_FRAME_POINTER
350 prompt "Single-depth WCHAN output"
353 Calculate simpler /proc/<PID>/wchan values. If this option
354 is disabled then wchan values will recurse back to the
355 caller function. This provides more accurate wchan values,
356 at the expense of slightly more scheduling overhead.
358 If in doubt, say "Y".
360 menuconfig PARAVIRT_GUEST
361 bool "Paravirtualized guest support"
363 Say Y here to get to see options related to running Linux under
364 various hypervisors. This option alone does not add any kernel code.
366 If you say N, all options in this submenu will be skipped and disabled.
370 source "arch/x86/xen/Kconfig"
373 bool "VMI Guest support"
376 depends on !(X86_VISWS || X86_VOYAGER)
378 VMI provides a paravirtualized interface to the VMware ESX server
379 (it could be used by other hypervisors in theory too, but is not
380 at the moment), by linking the kernel to a GPL-ed ROM module
381 provided by the hypervisor.
384 bool "KVM paravirtualized clock"
386 select PARAVIRT_CLOCK
387 depends on !(X86_VISWS || X86_VOYAGER)
389 Turning on this option will allow you to run a paravirtualized clock
390 when running over the KVM hypervisor. Instead of relying on a PIT
391 (or probably other) emulation by the underlying device model, the host
392 provides the guest with timing infrastructure such as time of day, and
396 bool "KVM Guest support"
398 depends on !(X86_VISWS || X86_VOYAGER)
400 This option enables various optimizations for running under the KVM
403 source "arch/x86/lguest/Kconfig"
406 bool "Enable paravirtualization code"
407 depends on !(X86_VISWS || X86_VOYAGER)
409 This changes the kernel so it can modify itself when it is run
410 under a hypervisor, potentially improving performance significantly
411 over full virtualization. However, when run without a hypervisor
412 the kernel is theoretically slower and slightly larger.
414 config PARAVIRT_CLOCK
425 This option adds a kernel parameter 'memtest', which allows memtest
427 memtest=0, mean disabled; -- default
428 memtest=1, mean do 1 test pattern;
430 memtest=4, mean do 4 test patterns.
431 If you are unsure how to answer this question, answer Y.
435 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
438 config HAVE_ARCH_PARSE_SRAT
442 config X86_SUMMIT_NUMA
444 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
446 config X86_CYCLONE_TIMER
448 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
450 config ES7000_CLUSTERED_APIC
452 depends on SMP && X86_ES7000 && MPENTIUMIII
454 source "arch/x86/Kconfig.cpu"
458 prompt "HPET Timer Support" if X86_32
460 Use the IA-PC HPET (High Precision Event Timer) to manage
461 time in preference to the PIT and RTC, if a HPET is
463 HPET is the next generation timer replacing legacy 8254s.
464 The HPET provides a stable time base on SMP
465 systems, unlike the TSC, but it is more expensive to access,
466 as it is off-chip. You can find the HPET spec at
467 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
469 You can safely choose Y here. However, HPET will only be
470 activated if the platform and the BIOS support this feature.
471 Otherwise the 8254 will be used for timing services.
473 Choose N to continue using the legacy 8254 timer.
475 config HPET_EMULATE_RTC
477 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
479 # Mark as embedded because too many people got it wrong.
480 # The code disables itself when not needed.
483 bool "Enable DMI scanning" if EMBEDDED
485 Enabled scanning of DMI to identify machine quirks. Say Y
486 here unless you have verified that your setup is not
487 affected by entries in the DMI blacklist. Required by PNP
491 bool "GART IOMMU support" if EMBEDDED
495 depends on X86_64 && PCI
497 Support for full DMA access of devices with 32bit memory access only
498 on systems with more than 3GB. This is usually needed for USB,
499 sound, many IDE/SATA chipsets and some other devices.
500 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
501 based hardware IOMMU and a software bounce buffer based IOMMU used
502 on Intel systems and as fallback.
503 The code is only active when needed (enough memory and limited
504 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
508 bool "IBM Calgary IOMMU support"
510 depends on X86_64 && PCI && EXPERIMENTAL
512 Support for hardware IOMMUs in IBM's xSeries x366 and x460
513 systems. Needed to run systems with more than 3GB of memory
514 properly with 32-bit PCI devices that do not support DAC
515 (Double Address Cycle). Calgary also supports bus level
516 isolation, where all DMAs pass through the IOMMU. This
517 prevents them from going anywhere except their intended
518 destination. This catches hard-to-find kernel bugs and
519 mis-behaving drivers and devices that do not use the DMA-API
520 properly to set up their DMA buffers. The IOMMU can be
521 turned off at boot time with the iommu=off parameter.
522 Normally the kernel will make the right choice by itself.
525 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
527 prompt "Should Calgary be enabled by default?"
528 depends on CALGARY_IOMMU
530 Should Calgary be enabled by default? if you choose 'y', Calgary
531 will be used (if it exists). If you choose 'n', Calgary will not be
532 used even if it exists. If you choose 'n' and would like to use
533 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
537 bool "AMD IOMMU support"
539 depends on X86_64 && PCI && ACPI
541 With this option you can enable support for AMD IOMMU hardware in
542 your system. An IOMMU is a hardware component which provides
543 remapping of DMA memory accesses from devices. With an AMD IOMMU you
544 can isolate the the DMA memory of different devices and protect the
545 system from misbehaving device drivers or hardware.
547 You can find out if your system has an AMD IOMMU if you look into
548 your BIOS for an option to enable it or if you have an IVRS ACPI
551 # need this always selected by IOMMU for the VIA workaround
555 Support for software bounce buffers used on x86-64 systems
556 which don't have a hardware IOMMU (e.g. the current generation
557 of Intel's x86-64 CPUs). Using this PCI devices which can only
558 access 32-bits of memory can be used on systems with more than
559 3 GB of memory. If unsure, say Y.
562 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
565 int "Maximum number of CPUs (2-4096)"
568 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
571 This allows you to specify the maximum number of CPUs which this
572 kernel will support. The maximum supported value is 4096 and the
573 minimum value which makes sense is 2.
575 This is purely to save memory - each supported CPU adds
576 approximately one kilobyte to the kernel image.
579 bool "SMT (Hyperthreading) scheduler support"
582 SMT scheduler support improves the CPU scheduler's decision making
583 when dealing with Intel Pentium 4 chips with HyperThreading at a
584 cost of slightly increased overhead in some places. If unsure say
589 prompt "Multi-core scheduler support"
592 Multi-core scheduler support improves the CPU scheduler's decision
593 making when dealing with multi-core CPU chips at a cost of slightly
594 increased overhead in some places. If unsure say N here.
596 source "kernel/Kconfig.preempt"
599 bool "Local APIC support on uniprocessors"
600 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
602 A local APIC (Advanced Programmable Interrupt Controller) is an
603 integrated interrupt controller in the CPU. If you have a single-CPU
604 system which has a processor with a local APIC, you can say Y here to
605 enable and use it. If you say Y here even though your machine doesn't
606 have a local APIC, then the kernel will still run with no slowdown at
607 all. The local APIC supports CPU-generated self-interrupts (timer,
608 performance counters), and the NMI watchdog which detects hard
612 bool "IO-APIC support on uniprocessors"
613 depends on X86_UP_APIC
615 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
616 SMP-capable replacement for PC-style interrupt controllers. Most
617 SMP systems and many recent uniprocessor systems have one.
619 If you have a single-CPU system with an IO-APIC, you can say Y here
620 to use it. If you say Y here even though your machine doesn't have
621 an IO-APIC, then the kernel will still run with no slowdown at all.
623 config X86_LOCAL_APIC
625 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
629 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
631 config X86_VISWS_APIC
633 depends on X86_32 && X86_VISWS
636 bool "Machine Check Exception"
637 depends on !X86_VOYAGER
639 Machine Check Exception support allows the processor to notify the
640 kernel if it detects a problem (e.g. overheating, component failure).
641 The action the kernel takes depends on the severity of the problem,
642 ranging from a warning message on the console, to halting the machine.
643 Your processor must be a Pentium or newer to support this - check the
644 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
645 have a design flaw which leads to false MCE events - hence MCE is
646 disabled on all P5 processors, unless explicitly enabled with "mce"
647 as a boot argument. Similarly, if MCE is built in and creates a
648 problem on some new non-standard machine, you can boot with "nomce"
649 to disable it. MCE support simply ignores non-MCE processors like
650 the 386 and 486, so nearly everyone can say Y here.
654 prompt "Intel MCE features"
655 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
657 Additional support for intel specific MCE features such as
662 prompt "AMD MCE features"
663 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
665 Additional support for AMD specific MCE features such as
666 the DRAM Error Threshold.
668 config X86_MCE_NONFATAL
669 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
670 depends on X86_32 && X86_MCE
672 Enabling this feature starts a timer that triggers every 5 seconds which
673 will look at the machine check registers to see if anything happened.
674 Non-fatal problems automatically get corrected (but still logged).
675 Disable this if you don't want to see these messages.
676 Seeing the messages this option prints out may be indicative of dying
677 or out-of-spec (ie, overclocked) hardware.
678 This option only does something on certain CPUs.
679 (AMD Athlon/Duron and Intel Pentium 4)
681 config X86_MCE_P4THERMAL
682 bool "check for P4 thermal throttling interrupt."
683 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
685 Enabling this feature will cause a message to be printed when the P4
686 enters thermal throttling.
689 bool "Enable VM86 support" if EMBEDDED
693 This option is required by programs like DOSEMU to run 16-bit legacy
694 code on X86 processors. It also may be needed by software like
695 XFree86 to initialize some video cards via BIOS. Disabling this
696 option saves about 6k.
699 tristate "Toshiba Laptop support"
702 This adds a driver to safely access the System Management Mode of
703 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
704 not work on models with a Phoenix BIOS. The System Management Mode
705 is used to set the BIOS and power saving options on Toshiba portables.
707 For information on utilities to make use of this driver see the
708 Toshiba Linux utilities web site at:
709 <http://www.buzzard.org.uk/toshiba/>.
711 Say Y if you intend to run this kernel on a Toshiba portable.
715 tristate "Dell laptop support"
717 This adds a driver to safely access the System Management Mode
718 of the CPU on the Dell Inspiron 8000. The System Management Mode
719 is used to read cpu temperature and cooling fan status and to
720 control the fans on the I8K portables.
722 This driver has been tested only on the Inspiron 8000 but it may
723 also work with other Dell laptops. You can force loading on other
724 models by passing the parameter `force=1' to the module. Use at
727 For information on utilities to make use of this driver see the
728 I8K Linux utilities web site at:
729 <http://people.debian.org/~dz/i8k/>
731 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
734 config X86_REBOOTFIXUPS
736 prompt "Enable X86 board specific fixups for reboot"
737 depends on X86_32 && X86
739 This enables chipset and/or board specific fixups to be done
740 in order to get reboot to work correctly. This is only needed on
741 some combinations of hardware and BIOS. The symptom, for which
742 this config is intended, is when reboot ends with a stalled/hung
745 Currently, the only fixup is for the Geode machines using
746 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
748 Say Y if you want to enable the fixup. Currently, it's safe to
749 enable this option even if you don't need it.
753 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
756 If you say Y here, you will be able to update the microcode on
757 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
758 Pentium III, Pentium 4, Xeon etc. You will obviously need the
759 actual microcode binary data itself which is not shipped with the
762 For latest news and information on obtaining all the required
763 ingredients for this driver, check:
764 <http://www.urbanmyth.org/microcode/>.
766 To compile this driver as a module, choose M here: the
767 module will be called microcode.
769 config MICROCODE_OLD_INTERFACE
774 tristate "/dev/cpu/*/msr - Model-specific register support"
776 This device gives privileged processes access to the x86
777 Model-Specific Registers (MSRs). It is a character device with
778 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
779 MSR accesses are directed to a specific CPU on multi-processor
783 tristate "/dev/cpu/*/cpuid - CPU information support"
785 This device gives processes access to the x86 CPUID instruction to
786 be executed on a specific processor. It is a character device
787 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
791 prompt "High Memory Support"
792 default HIGHMEM4G if !X86_NUMAQ
793 default HIGHMEM64G if X86_NUMAQ
798 depends on !X86_NUMAQ
800 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
801 However, the address space of 32-bit x86 processors is only 4
802 Gigabytes large. That means that, if you have a large amount of
803 physical memory, not all of it can be "permanently mapped" by the
804 kernel. The physical memory that's not permanently mapped is called
807 If you are compiling a kernel which will never run on a machine with
808 more than 1 Gigabyte total physical RAM, answer "off" here (default
809 choice and suitable for most users). This will result in a "3GB/1GB"
810 split: 3GB are mapped so that each process sees a 3GB virtual memory
811 space and the remaining part of the 4GB virtual memory space is used
812 by the kernel to permanently map as much physical memory as
815 If the machine has between 1 and 4 Gigabytes physical RAM, then
818 If more than 4 Gigabytes is used then answer "64GB" here. This
819 selection turns Intel PAE (Physical Address Extension) mode on.
820 PAE implements 3-level paging on IA32 processors. PAE is fully
821 supported by Linux, PAE mode is implemented on all recent Intel
822 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
823 then the kernel will not boot on CPUs that don't support PAE!
825 The actual amount of total physical memory will either be
826 auto detected or can be forced by using a kernel command line option
827 such as "mem=256M". (Try "man bootparam" or see the documentation of
828 your boot loader (lilo or loadlin) about how to pass options to the
829 kernel at boot time.)
831 If unsure, say "off".
835 depends on !X86_NUMAQ
837 Select this if you have a 32-bit processor and between 1 and 4
838 gigabytes of physical RAM.
842 depends on !M386 && !M486
845 Select this if you have a 32-bit processor and more than 4
846 gigabytes of physical RAM.
851 depends on EXPERIMENTAL
852 prompt "Memory split" if EMBEDDED
856 Select the desired split between kernel and user memory.
858 If the address range available to the kernel is less than the
859 physical memory installed, the remaining memory will be available
860 as "high memory". Accessing high memory is a little more costly
861 than low memory, as it needs to be mapped into the kernel first.
862 Note that increasing the kernel address space limits the range
863 available to user programs, making the address space there
864 tighter. Selecting anything other than the default 3G/1G split
865 will also likely make your kernel incompatible with binary-only
868 If you are not absolutely sure what you are doing, leave this
872 bool "3G/1G user/kernel split"
873 config VMSPLIT_3G_OPT
875 bool "3G/1G user/kernel split (for full 1G low memory)"
877 bool "2G/2G user/kernel split"
878 config VMSPLIT_2G_OPT
880 bool "2G/2G user/kernel split (for full 2G low memory)"
882 bool "1G/3G user/kernel split"
887 default 0xB0000000 if VMSPLIT_3G_OPT
888 default 0x80000000 if VMSPLIT_2G
889 default 0x78000000 if VMSPLIT_2G_OPT
890 default 0x40000000 if VMSPLIT_1G
896 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
900 prompt "PAE (Physical Address Extension) Support"
901 depends on X86_32 && !HIGHMEM4G
902 select RESOURCES_64BIT
904 PAE is required for NX support, and furthermore enables
905 larger swapspace support for non-overcommit purposes. It
906 has the cost of more pagetable lookup overhead, and also
907 consumes more pagetable space per process.
909 # Common NUMA Features
911 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
913 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
915 default y if (X86_NUMAQ || X86_SUMMIT)
917 Enable NUMA (Non Uniform Memory Access) support.
918 The kernel will try to allocate memory used by a CPU on the
919 local memory controller of the CPU and add some more
920 NUMA awareness to the kernel.
922 For i386 this is currently highly experimental and should be only
923 used for kernel development. It might also cause boot failures.
924 For x86_64 this is recommended on all multiprocessor Opteron systems.
925 If the system is EM64T, you should say N unless your system is
928 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
929 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
933 prompt "Old style AMD Opteron NUMA detection"
934 depends on X86_64 && NUMA && PCI
936 Enable K8 NUMA node topology detection. You should say Y here if
937 you have a multi processor AMD K8 system. This uses an old
938 method to read the NUMA configuration directly from the builtin
939 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
940 instead, which also takes priority if both are compiled in.
942 config X86_64_ACPI_NUMA
944 prompt "ACPI NUMA detection"
945 depends on X86_64 && NUMA && ACPI && PCI
948 Enable ACPI SRAT based node topology detection.
950 # Some NUMA nodes have memory ranges that span
951 # other nodes. Even though a pfn is valid and
952 # between a node's start and end pfns, it may not
953 # reside on that node. See memmap_init_zone()
955 config NODES_SPAN_OTHER_NODES
957 depends on X86_64_ACPI_NUMA
960 bool "NUMA emulation"
961 depends on X86_64 && NUMA
963 Enable NUMA emulation. A flat machine will be split
964 into virtual nodes when booted with "numa=fake=N", where N is the
965 number of nodes. This is only useful for debugging.
968 int "Max num nodes shift(1-9)"
970 default "6" if X86_64
971 default "4" if X86_NUMAQ
973 depends on NEED_MULTIPLE_NODES
975 config HAVE_ARCH_BOOTMEM_NODE
977 depends on X86_32 && NUMA
979 config ARCH_HAVE_MEMORY_PRESENT
981 depends on X86_32 && DISCONTIGMEM
983 config NEED_NODE_MEMMAP_SIZE
985 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
987 config HAVE_ARCH_ALLOC_REMAP
989 depends on X86_32 && NUMA
991 config ARCH_FLATMEM_ENABLE
993 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
995 config ARCH_DISCONTIGMEM_ENABLE
997 depends on NUMA && X86_32
999 config ARCH_DISCONTIGMEM_DEFAULT
1001 depends on NUMA && X86_32
1003 config ARCH_SPARSEMEM_DEFAULT
1007 config ARCH_SPARSEMEM_ENABLE
1009 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1010 select SPARSEMEM_STATIC if X86_32
1011 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1013 config ARCH_SELECT_MEMORY_MODEL
1015 depends on ARCH_SPARSEMEM_ENABLE
1017 config ARCH_MEMORY_PROBE
1019 depends on MEMORY_HOTPLUG
1024 bool "Allocate 3rd-level pagetables from highmem"
1025 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1027 The VM uses one page table entry for each page of physical memory.
1028 For systems with a lot of RAM, this can be wasteful of precious
1029 low memory. Setting this option will put user-space page table
1030 entries in high memory.
1032 config MATH_EMULATION
1034 prompt "Math emulation" if X86_32
1036 Linux can emulate a math coprocessor (used for floating point
1037 operations) if you don't have one. 486DX and Pentium processors have
1038 a math coprocessor built in, 486SX and 386 do not, unless you added
1039 a 487DX or 387, respectively. (The messages during boot time can
1040 give you some hints here ["man dmesg"].) Everyone needs either a
1041 coprocessor or this emulation.
1043 If you don't have a math coprocessor, you need to say Y here; if you
1044 say Y here even though you have a coprocessor, the coprocessor will
1045 be used nevertheless. (This behavior can be changed with the kernel
1046 command line option "no387", which comes handy if your coprocessor
1047 is broken. Try "man bootparam" or see the documentation of your boot
1048 loader (lilo or loadlin) about how to pass options to the kernel at
1049 boot time.) This means that it is a good idea to say Y here if you
1050 intend to use this kernel on different machines.
1052 More information about the internals of the Linux math coprocessor
1053 emulation can be found in <file:arch/x86/math-emu/README>.
1055 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1056 kernel, it won't hurt.
1059 bool "MTRR (Memory Type Range Register) support"
1061 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1062 the Memory Type Range Registers (MTRRs) may be used to control
1063 processor access to memory ranges. This is most useful if you have
1064 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1065 allows bus write transfers to be combined into a larger transfer
1066 before bursting over the PCI/AGP bus. This can increase performance
1067 of image write operations 2.5 times or more. Saying Y here creates a
1068 /proc/mtrr file which may be used to manipulate your processor's
1069 MTRRs. Typically the X server should use this.
1071 This code has a reasonably generic interface so that similar
1072 control registers on other processors can be easily supported
1075 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1076 Registers (ARRs) which provide a similar functionality to MTRRs. For
1077 these, the ARRs are used to emulate the MTRRs.
1078 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1079 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1080 write-combining. All of these processors are supported by this code
1081 and it makes sense to say Y here if you have one of them.
1083 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1084 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1085 can lead to all sorts of problems, so it's good to say Y here.
1087 You can safely say Y even if your machine doesn't have MTRRs, you'll
1088 just add about 9 KB to your kernel.
1090 See <file:Documentation/mtrr.txt> for more information.
1094 prompt "x86 PAT support"
1097 Use PAT attributes to setup page level cache control.
1099 PATs are the modern equivalents of MTRRs and are much more
1100 flexible than MTRRs.
1102 Say N here if you see bootup problems (boot crash, boot hang,
1103 spontaneous reboots) or a non-working video driver.
1109 prompt "EFI runtime service support"
1112 This enables the kernel to use EFI runtime services that are
1113 available (such as the EFI variable services).
1115 This option is only useful on systems that have EFI firmware.
1116 In addition, you should use the latest ELILO loader available
1117 at <http://elilo.sourceforge.net> in order to take advantage
1118 of EFI runtime services. However, even with this option, the
1119 resultant kernel should continue to boot on existing non-EFI
1124 prompt "Enable kernel irq balancing"
1125 depends on X86_32 && SMP && X86_IO_APIC
1127 The default yes will allow the kernel to do irq load balancing.
1128 Saying no will keep the kernel from doing irq load balancing.
1132 prompt "Enable seccomp to safely compute untrusted bytecode"
1135 This kernel feature is useful for number crunching applications
1136 that may need to compute untrusted bytecode during their
1137 execution. By using pipes or other transports made available to
1138 the process as file descriptors supporting the read/write
1139 syscalls, it's possible to isolate those applications in
1140 their own address space using seccomp. Once seccomp is
1141 enabled via /proc/<pid>/seccomp, it cannot be disabled
1142 and the task is only allowed to execute a few safe syscalls
1143 defined by each seccomp mode.
1145 If unsure, say Y. Only embedded should say N here.
1147 config CC_STACKPROTECTOR
1148 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1149 depends on X86_64 && EXPERIMENTAL && BROKEN
1151 This option turns on the -fstack-protector GCC feature. This
1152 feature puts, at the beginning of critical functions, a canary
1153 value on the stack just before the return address, and validates
1154 the value just before actually returning. Stack based buffer
1155 overflows (that need to overwrite this return address) now also
1156 overwrite the canary, which gets detected and the attack is then
1157 neutralized via a kernel panic.
1159 This feature requires gcc version 4.2 or above, or a distribution
1160 gcc with the feature backported. Older versions are automatically
1161 detected and for those versions, this configuration option is ignored.
1163 config CC_STACKPROTECTOR_ALL
1164 bool "Use stack-protector for all functions"
1165 depends on CC_STACKPROTECTOR
1167 Normally, GCC only inserts the canary value protection for
1168 functions that use large-ish on-stack buffers. By enabling
1169 this option, GCC will be asked to do this for ALL functions.
1171 source kernel/Kconfig.hz
1174 bool "kexec system call"
1175 depends on X86_BIOS_REBOOT
1177 kexec is a system call that implements the ability to shutdown your
1178 current kernel, and to start another kernel. It is like a reboot
1179 but it is independent of the system firmware. And like a reboot
1180 you can start any kernel with it, not just Linux.
1182 The name comes from the similarity to the exec system call.
1184 It is an ongoing process to be certain the hardware in a machine
1185 is properly shutdown, so do not be surprised if this code does not
1186 initially work for you. It may help to enable device hotplugging
1187 support. As of this writing the exact hardware interface is
1188 strongly in flux, so no good recommendation can be made.
1191 bool "kernel crash dumps (EXPERIMENTAL)"
1192 depends on EXPERIMENTAL
1193 depends on X86_64 || (X86_32 && HIGHMEM)
1195 Generate crash dump after being started by kexec.
1196 This should be normally only set in special crash dump kernels
1197 which are loaded in the main kernel with kexec-tools into
1198 a specially reserved region and then later executed after
1199 a crash by kdump/kexec. The crash dump kernel must be compiled
1200 to a memory address not used by the main kernel or BIOS using
1201 PHYSICAL_START, or it must be built as a relocatable image
1202 (CONFIG_RELOCATABLE=y).
1203 For more details see Documentation/kdump/kdump.txt
1205 config PHYSICAL_START
1206 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1207 default "0x1000000" if X86_NUMAQ
1208 default "0x200000" if X86_64
1211 This gives the physical address where the kernel is loaded.
1213 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1214 bzImage will decompress itself to above physical address and
1215 run from there. Otherwise, bzImage will run from the address where
1216 it has been loaded by the boot loader and will ignore above physical
1219 In normal kdump cases one does not have to set/change this option
1220 as now bzImage can be compiled as a completely relocatable image
1221 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1222 address. This option is mainly useful for the folks who don't want
1223 to use a bzImage for capturing the crash dump and want to use a
1224 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1225 to be specifically compiled to run from a specific memory area
1226 (normally a reserved region) and this option comes handy.
1228 So if you are using bzImage for capturing the crash dump, leave
1229 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1230 Otherwise if you plan to use vmlinux for capturing the crash dump
1231 change this value to start of the reserved region (Typically 16MB
1232 0x1000000). In other words, it can be set based on the "X" value as
1233 specified in the "crashkernel=YM@XM" command line boot parameter
1234 passed to the panic-ed kernel. Typically this parameter is set as
1235 crashkernel=64M@16M. Please take a look at
1236 Documentation/kdump/kdump.txt for more details about crash dumps.
1238 Usage of bzImage for capturing the crash dump is recommended as
1239 one does not have to build two kernels. Same kernel can be used
1240 as production kernel and capture kernel. Above option should have
1241 gone away after relocatable bzImage support is introduced. But it
1242 is present because there are users out there who continue to use
1243 vmlinux for dump capture. This option should go away down the
1246 Don't change this unless you know what you are doing.
1249 bool "Build a relocatable kernel (EXPERIMENTAL)"
1250 depends on EXPERIMENTAL
1252 This builds a kernel image that retains relocation information
1253 so it can be loaded someplace besides the default 1MB.
1254 The relocations tend to make the kernel binary about 10% larger,
1255 but are discarded at runtime.
1257 One use is for the kexec on panic case where the recovery kernel
1258 must live at a different physical address than the primary
1261 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1262 it has been loaded at and the compile time physical address
1263 (CONFIG_PHYSICAL_START) is ignored.
1265 config PHYSICAL_ALIGN
1267 prompt "Alignment value to which kernel should be aligned" if X86_32
1268 default "0x100000" if X86_32
1269 default "0x200000" if X86_64
1270 range 0x2000 0x400000
1272 This value puts the alignment restrictions on physical address
1273 where kernel is loaded and run from. Kernel is compiled for an
1274 address which meets above alignment restriction.
1276 If bootloader loads the kernel at a non-aligned address and
1277 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1278 address aligned to above value and run from there.
1280 If bootloader loads the kernel at a non-aligned address and
1281 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1282 load address and decompress itself to the address it has been
1283 compiled for and run from there. The address for which kernel is
1284 compiled already meets above alignment restrictions. Hence the
1285 end result is that kernel runs from a physical address meeting
1286 above alignment restrictions.
1288 Don't change this unless you know what you are doing.
1291 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1292 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1294 Say Y here to experiment with turning CPUs off and on, and to
1295 enable suspend on SMP systems. CPUs can be controlled through
1296 /sys/devices/system/cpu.
1297 Say N if you want to disable CPU hotplug and don't need to
1302 prompt "Compat VDSO support"
1303 depends on X86_32 || IA32_EMULATION
1305 Map the 32-bit VDSO to the predictable old-style address too.
1307 Say N here if you are running a sufficiently recent glibc
1308 version (2.3.3 or later), to remove the high-mapped
1309 VDSO mapping and to exclusively use the randomized VDSO.
1315 config ARCH_ENABLE_MEMORY_HOTPLUG
1317 depends on X86_64 || (X86_32 && HIGHMEM)
1319 config HAVE_ARCH_EARLY_PFN_TO_NID
1323 menu "Power management options"
1324 depends on !X86_VOYAGER
1326 config ARCH_HIBERNATION_HEADER
1328 depends on X86_64 && HIBERNATION
1330 source "kernel/power/Kconfig"
1332 source "drivers/acpi/Kconfig"
1337 depends on APM || APM_MODULE
1340 tristate "APM (Advanced Power Management) BIOS support"
1341 depends on X86_32 && PM_SLEEP && !X86_VISWS
1343 APM is a BIOS specification for saving power using several different
1344 techniques. This is mostly useful for battery powered laptops with
1345 APM compliant BIOSes. If you say Y here, the system time will be
1346 reset after a RESUME operation, the /proc/apm device will provide
1347 battery status information, and user-space programs will receive
1348 notification of APM "events" (e.g. battery status change).
1350 If you select "Y" here, you can disable actual use of the APM
1351 BIOS by passing the "apm=off" option to the kernel at boot time.
1353 Note that the APM support is almost completely disabled for
1354 machines with more than one CPU.
1356 In order to use APM, you will need supporting software. For location
1357 and more information, read <file:Documentation/power/pm.txt> and the
1358 Battery Powered Linux mini-HOWTO, available from
1359 <http://www.tldp.org/docs.html#howto>.
1361 This driver does not spin down disk drives (see the hdparm(8)
1362 manpage ("man 8 hdparm") for that), and it doesn't turn off
1363 VESA-compliant "green" monitors.
1365 This driver does not support the TI 4000M TravelMate and the ACER
1366 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1367 desktop machines also don't have compliant BIOSes, and this driver
1368 may cause those machines to panic during the boot phase.
1370 Generally, if you don't have a battery in your machine, there isn't
1371 much point in using this driver and you should say N. If you get
1372 random kernel OOPSes or reboots that don't seem to be related to
1373 anything, try disabling/enabling this option (or disabling/enabling
1376 Some other things you should try when experiencing seemingly random,
1379 1) make sure that you have enough swap space and that it is
1381 2) pass the "no-hlt" option to the kernel
1382 3) switch on floating point emulation in the kernel and pass
1383 the "no387" option to the kernel
1384 4) pass the "floppy=nodma" option to the kernel
1385 5) pass the "mem=4M" option to the kernel (thereby disabling
1386 all but the first 4 MB of RAM)
1387 6) make sure that the CPU is not over clocked.
1388 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1389 8) disable the cache from your BIOS settings
1390 9) install a fan for the video card or exchange video RAM
1391 10) install a better fan for the CPU
1392 11) exchange RAM chips
1393 12) exchange the motherboard.
1395 To compile this driver as a module, choose M here: the
1396 module will be called apm.
1400 config APM_IGNORE_USER_SUSPEND
1401 bool "Ignore USER SUSPEND"
1403 This option will ignore USER SUSPEND requests. On machines with a
1404 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1405 series notebooks, it is necessary to say Y because of a BIOS bug.
1407 config APM_DO_ENABLE
1408 bool "Enable PM at boot time"
1410 Enable APM features at boot time. From page 36 of the APM BIOS
1411 specification: "When disabled, the APM BIOS does not automatically
1412 power manage devices, enter the Standby State, enter the Suspend
1413 State, or take power saving steps in response to CPU Idle calls."
1414 This driver will make CPU Idle calls when Linux is idle (unless this
1415 feature is turned off -- see "Do CPU IDLE calls", below). This
1416 should always save battery power, but more complicated APM features
1417 will be dependent on your BIOS implementation. You may need to turn
1418 this option off if your computer hangs at boot time when using APM
1419 support, or if it beeps continuously instead of suspending. Turn
1420 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1421 T400CDT. This is off by default since most machines do fine without
1425 bool "Make CPU Idle calls when idle"
1427 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1428 On some machines, this can activate improved power savings, such as
1429 a slowed CPU clock rate, when the machine is idle. These idle calls
1430 are made after the idle loop has run for some length of time (e.g.,
1431 333 mS). On some machines, this will cause a hang at boot time or
1432 whenever the CPU becomes idle. (On machines with more than one CPU,
1433 this option does nothing.)
1435 config APM_DISPLAY_BLANK
1436 bool "Enable console blanking using APM"
1438 Enable console blanking using the APM. Some laptops can use this to
1439 turn off the LCD backlight when the screen blanker of the Linux
1440 virtual console blanks the screen. Note that this is only used by
1441 the virtual console screen blanker, and won't turn off the backlight
1442 when using the X Window system. This also doesn't have anything to
1443 do with your VESA-compliant power-saving monitor. Further, this
1444 option doesn't work for all laptops -- it might not turn off your
1445 backlight at all, or it might print a lot of errors to the console,
1446 especially if you are using gpm.
1448 config APM_ALLOW_INTS
1449 bool "Allow interrupts during APM BIOS calls"
1451 Normally we disable external interrupts while we are making calls to
1452 the APM BIOS as a measure to lessen the effects of a badly behaving
1453 BIOS implementation. The BIOS should reenable interrupts if it
1454 needs to. Unfortunately, some BIOSes do not -- especially those in
1455 many of the newer IBM Thinkpads. If you experience hangs when you
1456 suspend, try setting this to Y. Otherwise, say N.
1458 config APM_REAL_MODE_POWER_OFF
1459 bool "Use real mode APM BIOS call to power off"
1461 Use real mode APM BIOS calls to switch off the computer. This is
1462 a work-around for a number of buggy BIOSes. Switch this option on if
1463 your computer crashes instead of powering off properly.
1467 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1469 source "drivers/cpuidle/Kconfig"
1474 menu "Bus options (PCI etc.)"
1479 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1481 Find out whether you have a PCI motherboard. PCI is the name of a
1482 bus system, i.e. the way the CPU talks to the other stuff inside
1483 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1484 VESA. If you have PCI, say Y, otherwise N.
1487 prompt "PCI access mode"
1488 depends on X86_32 && PCI && !X86_VISWS
1491 On PCI systems, the BIOS can be used to detect the PCI devices and
1492 determine their configuration. However, some old PCI motherboards
1493 have BIOS bugs and may crash if this is done. Also, some embedded
1494 PCI-based systems don't have any BIOS at all. Linux can also try to
1495 detect the PCI hardware directly without using the BIOS.
1497 With this option, you can specify how Linux should detect the
1498 PCI devices. If you choose "BIOS", the BIOS will be used,
1499 if you choose "Direct", the BIOS won't be used, and if you
1500 choose "MMConfig", then PCI Express MMCONFIG will be used.
1501 If you choose "Any", the kernel will try MMCONFIG, then the
1502 direct access method and falls back to the BIOS if that doesn't
1503 work. If unsure, go with the default, which is "Any".
1508 config PCI_GOMMCONFIG
1525 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1527 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1530 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
1534 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1538 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1545 bool "Support mmconfig PCI config space access"
1546 depends on X86_64 && PCI && ACPI
1549 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1550 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1552 DMA remapping (DMAR) devices support enables independent address
1553 translations for Direct Memory Access (DMA) from devices.
1554 These DMA remapping devices are reported via ACPI tables
1555 and include PCI device scope covered by these DMA
1560 prompt "Support for Graphics workaround"
1563 Current Graphics drivers tend to use physical address
1564 for DMA and avoid using DMA APIs. Setting this config
1565 option permits the IOMMU driver to set a unity map for
1566 all the OS-visible memory. Hence the driver can continue
1567 to use physical addresses for DMA.
1569 config DMAR_FLOPPY_WA
1573 Floppy disk drivers are know to bypass DMA API calls
1574 thereby failing to work when IOMMU is enabled. This
1575 workaround will setup a 1:1 mapping for the first
1576 16M to make floppy (an ISA device) work.
1578 source "drivers/pci/pcie/Kconfig"
1580 source "drivers/pci/Kconfig"
1582 # x86_64 have no ISA slots, but do have ISA-style DMA.
1590 depends on !(X86_VOYAGER || X86_VISWS)
1592 Find out whether you have ISA slots on your motherboard. ISA is the
1593 name of a bus system, i.e. the way the CPU talks to the other stuff
1594 inside your box. Other bus systems are PCI, EISA, MicroChannel
1595 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1596 newer boards don't support it. If you have ISA, say Y, otherwise N.
1602 The Extended Industry Standard Architecture (EISA) bus was
1603 developed as an open alternative to the IBM MicroChannel bus.
1605 The EISA bus provided some of the features of the IBM MicroChannel
1606 bus while maintaining backward compatibility with cards made for
1607 the older ISA bus. The EISA bus saw limited use between 1988 and
1608 1995 when it was made obsolete by the PCI bus.
1610 Say Y here if you are building a kernel for an EISA-based machine.
1614 source "drivers/eisa/Kconfig"
1617 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1618 default y if X86_VOYAGER
1620 MicroChannel Architecture is found in some IBM PS/2 machines and
1621 laptops. It is a bus system similar to PCI or ISA. See
1622 <file:Documentation/mca.txt> (and especially the web page given
1623 there) before attempting to build an MCA bus kernel.
1625 source "drivers/mca/Kconfig"
1628 tristate "NatSemi SCx200 support"
1629 depends on !X86_VOYAGER
1631 This provides basic support for National Semiconductor's
1632 (now AMD's) Geode processors. The driver probes for the
1633 PCI-IDs of several on-chip devices, so its a good dependency
1634 for other scx200_* drivers.
1636 If compiled as a module, the driver is named scx200.
1638 config SCx200HR_TIMER
1639 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1640 depends on SCx200 && GENERIC_TIME
1643 This driver provides a clocksource built upon the on-chip
1644 27MHz high-resolution timer. Its also a workaround for
1645 NSC Geode SC-1100's buggy TSC, which loses time when the
1646 processor goes idle (as is done by the scheduler). The
1647 other workaround is idle=poll boot option.
1649 config GEODE_MFGPT_TIMER
1651 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1652 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1654 This driver provides a clock event source based on the MFGPT
1655 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1656 MFGPTs have a better resolution and max interval than the
1657 generic PIT, and are suitable for use as high-res timers.
1660 bool "One Laptop Per Child support"
1663 Add support for detecting the unique features of the OLPC
1670 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1672 source "drivers/pcmcia/Kconfig"
1674 source "drivers/pci/hotplug/Kconfig"
1679 menu "Executable file formats / Emulations"
1681 source "fs/Kconfig.binfmt"
1683 config IA32_EMULATION
1684 bool "IA32 Emulation"
1686 select COMPAT_BINFMT_ELF
1688 Include code to run 32-bit programs under a 64-bit kernel. You should
1689 likely turn this on, unless you're 100% sure that you don't have any
1690 32-bit programs left.
1693 tristate "IA32 a.out support"
1694 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1696 Support old a.out binaries in the 32bit emulation.
1700 depends on IA32_EMULATION
1702 config COMPAT_FOR_U64_ALIGNMENT
1706 config SYSVIPC_COMPAT
1708 depends on X86_64 && COMPAT && SYSVIPC
1713 source "net/Kconfig"
1715 source "drivers/Kconfig"
1717 source "drivers/firmware/Kconfig"
1721 source "arch/x86/Kconfig.debug"
1723 source "security/Kconfig"
1725 source "crypto/Kconfig"
1727 source "arch/x86/kvm/Kconfig"
1729 source "lib/Kconfig"
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