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)
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
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)"
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"
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 depends on !(X86_VISWS || X86_VOYAGER)
388 Turning on this option will allow you to run a paravirtualized clock
389 when running over the KVM hypervisor. Instead of relying on a PIT
390 (or probably other) emulation by the underlying device model, the host
391 provides the guest with timing infrastructure such as time of day, and
395 bool "KVM Guest support"
397 depends on !(X86_VISWS || X86_VOYAGER)
399 This option enables various optimizations for running under the KVM
402 source "arch/x86/lguest/Kconfig"
405 bool "Enable paravirtualization code"
406 depends on !(X86_VISWS || X86_VOYAGER)
408 This changes the kernel so it can modify itself when it is run
409 under a hypervisor, potentially improving performance significantly
410 over full virtualization. However, when run without a hypervisor
411 the kernel is theoretically slower and slightly larger.
415 config MEMTEST_BOOTPARAM
416 bool "Memtest boot parameter"
420 This option adds a kernel parameter 'memtest', which allows memtest
421 to be disabled at boot. If this option is selected, memtest
422 functionality can be disabled with memtest=0 on the kernel
423 command line. The purpose of this option is to allow a single
424 kernel image to be distributed with memtest built in, but not
427 If you are unsure how to answer this question, answer Y.
429 config MEMTEST_BOOTPARAM_VALUE
430 int "Memtest boot parameter default value (0-4)"
431 depends on MEMTEST_BOOTPARAM
435 This option sets the default value for the kernel parameter
436 'memtest', which allows memtest to be disabled at boot. If this
437 option is set to 0 (zero), the memtest kernel parameter will
438 default to 0, disabling memtest at bootup. If this option is
439 set to 4, the memtest kernel parameter will default to 4,
440 enabling memtest at bootup, and use that as pattern number.
442 If you are unsure how to answer this question, answer 0.
446 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
449 config HAVE_ARCH_PARSE_SRAT
453 config X86_SUMMIT_NUMA
455 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
457 config X86_CYCLONE_TIMER
459 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
461 config ES7000_CLUSTERED_APIC
463 depends on SMP && X86_ES7000 && MPENTIUMIII
465 source "arch/x86/Kconfig.cpu"
469 prompt "HPET Timer Support" if X86_32
471 Use the IA-PC HPET (High Precision Event Timer) to manage
472 time in preference to the PIT and RTC, if a HPET is
474 HPET is the next generation timer replacing legacy 8254s.
475 The HPET provides a stable time base on SMP
476 systems, unlike the TSC, but it is more expensive to access,
477 as it is off-chip. You can find the HPET spec at
478 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
480 You can safely choose Y here. However, HPET will only be
481 activated if the platform and the BIOS support this feature.
482 Otherwise the 8254 will be used for timing services.
484 Choose N to continue using the legacy 8254 timer.
486 config HPET_EMULATE_RTC
488 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
490 # Mark as embedded because too many people got it wrong.
491 # The code disables itself when not needed.
494 bool "Enable DMI scanning" if EMBEDDED
496 Enabled scanning of DMI to identify machine quirks. Say Y
497 here unless you have verified that your setup is not
498 affected by entries in the DMI blacklist. Required by PNP
502 bool "GART IOMMU support" if EMBEDDED
506 depends on X86_64 && PCI
508 Support for full DMA access of devices with 32bit memory access only
509 on systems with more than 3GB. This is usually needed for USB,
510 sound, many IDE/SATA chipsets and some other devices.
511 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
512 based hardware IOMMU and a software bounce buffer based IOMMU used
513 on Intel systems and as fallback.
514 The code is only active when needed (enough memory and limited
515 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
519 bool "IBM Calgary IOMMU support"
521 depends on X86_64 && PCI && EXPERIMENTAL
523 Support for hardware IOMMUs in IBM's xSeries x366 and x460
524 systems. Needed to run systems with more than 3GB of memory
525 properly with 32-bit PCI devices that do not support DAC
526 (Double Address Cycle). Calgary also supports bus level
527 isolation, where all DMAs pass through the IOMMU. This
528 prevents them from going anywhere except their intended
529 destination. This catches hard-to-find kernel bugs and
530 mis-behaving drivers and devices that do not use the DMA-API
531 properly to set up their DMA buffers. The IOMMU can be
532 turned off at boot time with the iommu=off parameter.
533 Normally the kernel will make the right choice by itself.
536 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
538 prompt "Should Calgary be enabled by default?"
539 depends on CALGARY_IOMMU
541 Should Calgary be enabled by default? if you choose 'y', Calgary
542 will be used (if it exists). If you choose 'n', Calgary will not be
543 used even if it exists. If you choose 'n' and would like to use
544 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
547 # need this always selected by IOMMU for the VIA workaround
551 Support for software bounce buffers used on x86-64 systems
552 which don't have a hardware IOMMU (e.g. the current generation
553 of Intel's x86-64 CPUs). Using this PCI devices which can only
554 access 32-bits of memory can be used on systems with more than
555 3 GB of memory. If unsure, say Y.
558 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
561 int "Maximum number of CPUs (2-255)"
564 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
567 This allows you to specify the maximum number of CPUs which this
568 kernel will support. The maximum supported value is 255 and the
569 minimum value which makes sense is 2.
571 This is purely to save memory - each supported CPU adds
572 approximately eight kilobytes to the kernel image.
575 bool "SMT (Hyperthreading) scheduler support"
578 SMT scheduler support improves the CPU scheduler's decision making
579 when dealing with Intel Pentium 4 chips with HyperThreading at a
580 cost of slightly increased overhead in some places. If unsure say
585 prompt "Multi-core scheduler support"
588 Multi-core scheduler support improves the CPU scheduler's decision
589 making when dealing with multi-core CPU chips at a cost of slightly
590 increased overhead in some places. If unsure say N here.
592 source "kernel/Kconfig.preempt"
595 bool "Local APIC support on uniprocessors"
596 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
598 A local APIC (Advanced Programmable Interrupt Controller) is an
599 integrated interrupt controller in the CPU. If you have a single-CPU
600 system which has a processor with a local APIC, you can say Y here to
601 enable and use it. If you say Y here even though your machine doesn't
602 have a local APIC, then the kernel will still run with no slowdown at
603 all. The local APIC supports CPU-generated self-interrupts (timer,
604 performance counters), and the NMI watchdog which detects hard
608 bool "IO-APIC support on uniprocessors"
609 depends on X86_UP_APIC
611 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
612 SMP-capable replacement for PC-style interrupt controllers. Most
613 SMP systems and many recent uniprocessor systems have one.
615 If you have a single-CPU system with an IO-APIC, you can say Y here
616 to use it. If you say Y here even though your machine doesn't have
617 an IO-APIC, then the kernel will still run with no slowdown at all.
619 config X86_LOCAL_APIC
621 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
625 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
627 config X86_VISWS_APIC
629 depends on X86_32 && X86_VISWS
632 bool "Machine Check Exception"
633 depends on !X86_VOYAGER
635 Machine Check Exception support allows the processor to notify the
636 kernel if it detects a problem (e.g. overheating, component failure).
637 The action the kernel takes depends on the severity of the problem,
638 ranging from a warning message on the console, to halting the machine.
639 Your processor must be a Pentium or newer to support this - check the
640 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
641 have a design flaw which leads to false MCE events - hence MCE is
642 disabled on all P5 processors, unless explicitly enabled with "mce"
643 as a boot argument. Similarly, if MCE is built in and creates a
644 problem on some new non-standard machine, you can boot with "nomce"
645 to disable it. MCE support simply ignores non-MCE processors like
646 the 386 and 486, so nearly everyone can say Y here.
650 prompt "Intel MCE features"
651 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
653 Additional support for intel specific MCE features such as
658 prompt "AMD MCE features"
659 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
661 Additional support for AMD specific MCE features such as
662 the DRAM Error Threshold.
664 config X86_MCE_NONFATAL
665 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
666 depends on X86_32 && X86_MCE
668 Enabling this feature starts a timer that triggers every 5 seconds which
669 will look at the machine check registers to see if anything happened.
670 Non-fatal problems automatically get corrected (but still logged).
671 Disable this if you don't want to see these messages.
672 Seeing the messages this option prints out may be indicative of dying
673 or out-of-spec (ie, overclocked) hardware.
674 This option only does something on certain CPUs.
675 (AMD Athlon/Duron and Intel Pentium 4)
677 config X86_MCE_P4THERMAL
678 bool "check for P4 thermal throttling interrupt."
679 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
681 Enabling this feature will cause a message to be printed when the P4
682 enters thermal throttling.
685 bool "Enable VM86 support" if EMBEDDED
689 This option is required by programs like DOSEMU to run 16-bit legacy
690 code on X86 processors. It also may be needed by software like
691 XFree86 to initialize some video cards via BIOS. Disabling this
692 option saves about 6k.
695 tristate "Toshiba Laptop support"
698 This adds a driver to safely access the System Management Mode of
699 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
700 not work on models with a Phoenix BIOS. The System Management Mode
701 is used to set the BIOS and power saving options on Toshiba portables.
703 For information on utilities to make use of this driver see the
704 Toshiba Linux utilities web site at:
705 <http://www.buzzard.org.uk/toshiba/>.
707 Say Y if you intend to run this kernel on a Toshiba portable.
711 tristate "Dell laptop support"
713 This adds a driver to safely access the System Management Mode
714 of the CPU on the Dell Inspiron 8000. The System Management Mode
715 is used to read cpu temperature and cooling fan status and to
716 control the fans on the I8K portables.
718 This driver has been tested only on the Inspiron 8000 but it may
719 also work with other Dell laptops. You can force loading on other
720 models by passing the parameter `force=1' to the module. Use at
723 For information on utilities to make use of this driver see the
724 I8K Linux utilities web site at:
725 <http://people.debian.org/~dz/i8k/>
727 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
730 config X86_REBOOTFIXUPS
732 prompt "Enable X86 board specific fixups for reboot"
733 depends on X86_32 && X86
735 This enables chipset and/or board specific fixups to be done
736 in order to get reboot to work correctly. This is only needed on
737 some combinations of hardware and BIOS. The symptom, for which
738 this config is intended, is when reboot ends with a stalled/hung
741 Currently, the only fixup is for the Geode machines using
742 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
744 Say Y if you want to enable the fixup. Currently, it's safe to
745 enable this option even if you don't need it.
749 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
752 If you say Y here, you will be able to update the microcode on
753 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
754 Pentium III, Pentium 4, Xeon etc. You will obviously need the
755 actual microcode binary data itself which is not shipped with the
758 For latest news and information on obtaining all the required
759 ingredients for this driver, check:
760 <http://www.urbanmyth.org/microcode/>.
762 To compile this driver as a module, choose M here: the
763 module will be called microcode.
765 config MICROCODE_OLD_INTERFACE
770 tristate "/dev/cpu/*/msr - Model-specific register support"
772 This device gives privileged processes access to the x86
773 Model-Specific Registers (MSRs). It is a character device with
774 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
775 MSR accesses are directed to a specific CPU on multi-processor
779 tristate "/dev/cpu/*/cpuid - CPU information support"
781 This device gives processes access to the x86 CPUID instruction to
782 be executed on a specific processor. It is a character device
783 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
787 prompt "High Memory Support"
788 default HIGHMEM4G if !X86_NUMAQ
789 default HIGHMEM64G if X86_NUMAQ
794 depends on !X86_NUMAQ
796 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
797 However, the address space of 32-bit x86 processors is only 4
798 Gigabytes large. That means that, if you have a large amount of
799 physical memory, not all of it can be "permanently mapped" by the
800 kernel. The physical memory that's not permanently mapped is called
803 If you are compiling a kernel which will never run on a machine with
804 more than 1 Gigabyte total physical RAM, answer "off" here (default
805 choice and suitable for most users). This will result in a "3GB/1GB"
806 split: 3GB are mapped so that each process sees a 3GB virtual memory
807 space and the remaining part of the 4GB virtual memory space is used
808 by the kernel to permanently map as much physical memory as
811 If the machine has between 1 and 4 Gigabytes physical RAM, then
814 If more than 4 Gigabytes is used then answer "64GB" here. This
815 selection turns Intel PAE (Physical Address Extension) mode on.
816 PAE implements 3-level paging on IA32 processors. PAE is fully
817 supported by Linux, PAE mode is implemented on all recent Intel
818 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
819 then the kernel will not boot on CPUs that don't support PAE!
821 The actual amount of total physical memory will either be
822 auto detected or can be forced by using a kernel command line option
823 such as "mem=256M". (Try "man bootparam" or see the documentation of
824 your boot loader (lilo or loadlin) about how to pass options to the
825 kernel at boot time.)
827 If unsure, say "off".
831 depends on !X86_NUMAQ
833 Select this if you have a 32-bit processor and between 1 and 4
834 gigabytes of physical RAM.
838 depends on !M386 && !M486
841 Select this if you have a 32-bit processor and more than 4
842 gigabytes of physical RAM.
847 depends on EXPERIMENTAL
848 prompt "Memory split" if EMBEDDED
852 Select the desired split between kernel and user memory.
854 If the address range available to the kernel is less than the
855 physical memory installed, the remaining memory will be available
856 as "high memory". Accessing high memory is a little more costly
857 than low memory, as it needs to be mapped into the kernel first.
858 Note that increasing the kernel address space limits the range
859 available to user programs, making the address space there
860 tighter. Selecting anything other than the default 3G/1G split
861 will also likely make your kernel incompatible with binary-only
864 If you are not absolutely sure what you are doing, leave this
868 bool "3G/1G user/kernel split"
869 config VMSPLIT_3G_OPT
871 bool "3G/1G user/kernel split (for full 1G low memory)"
873 bool "2G/2G user/kernel split"
874 config VMSPLIT_2G_OPT
876 bool "2G/2G user/kernel split (for full 2G low memory)"
878 bool "1G/3G user/kernel split"
883 default 0xB0000000 if VMSPLIT_3G_OPT
884 default 0x80000000 if VMSPLIT_2G
885 default 0x78000000 if VMSPLIT_2G_OPT
886 default 0x40000000 if VMSPLIT_1G
892 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
896 prompt "PAE (Physical Address Extension) Support"
897 depends on X86_32 && !HIGHMEM4G
898 select RESOURCES_64BIT
900 PAE is required for NX support, and furthermore enables
901 larger swapspace support for non-overcommit purposes. It
902 has the cost of more pagetable lookup overhead, and also
903 consumes more pagetable space per process.
905 # Common NUMA Features
907 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
909 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
911 default y if (X86_NUMAQ || X86_SUMMIT)
913 Enable NUMA (Non Uniform Memory Access) support.
914 The kernel will try to allocate memory used by a CPU on the
915 local memory controller of the CPU and add some more
916 NUMA awareness to the kernel.
918 For i386 this is currently highly experimental and should be only
919 used for kernel development. It might also cause boot failures.
920 For x86_64 this is recommended on all multiprocessor Opteron systems.
921 If the system is EM64T, you should say N unless your system is
924 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
925 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
929 prompt "Old style AMD Opteron NUMA detection"
930 depends on X86_64 && NUMA && PCI
932 Enable K8 NUMA node topology detection. You should say Y here if
933 you have a multi processor AMD K8 system. This uses an old
934 method to read the NUMA configuration directly from the builtin
935 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
936 instead, which also takes priority if both are compiled in.
938 config X86_64_ACPI_NUMA
940 prompt "ACPI NUMA detection"
941 depends on X86_64 && NUMA && ACPI && PCI
944 Enable ACPI SRAT based node topology detection.
946 # Some NUMA nodes have memory ranges that span
947 # other nodes. Even though a pfn is valid and
948 # between a node's start and end pfns, it may not
949 # reside on that node. See memmap_init_zone()
951 config NODES_SPAN_OTHER_NODES
953 depends on X86_64_ACPI_NUMA
956 bool "NUMA emulation"
957 depends on X86_64 && NUMA
959 Enable NUMA emulation. A flat machine will be split
960 into virtual nodes when booted with "numa=fake=N", where N is the
961 number of nodes. This is only useful for debugging.
964 int "Max num nodes shift(1-15)"
966 default "6" if X86_64
967 default "4" if X86_NUMAQ
969 depends on NEED_MULTIPLE_NODES
971 config HAVE_ARCH_BOOTMEM_NODE
973 depends on X86_32 && NUMA
975 config ARCH_HAVE_MEMORY_PRESENT
977 depends on X86_32 && DISCONTIGMEM
979 config NEED_NODE_MEMMAP_SIZE
981 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
983 config HAVE_ARCH_ALLOC_REMAP
985 depends on X86_32 && NUMA
987 config ARCH_FLATMEM_ENABLE
989 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
991 config ARCH_DISCONTIGMEM_ENABLE
993 depends on NUMA && X86_32
995 config ARCH_DISCONTIGMEM_DEFAULT
997 depends on NUMA && X86_32
999 config ARCH_SPARSEMEM_DEFAULT
1003 config ARCH_SPARSEMEM_ENABLE
1005 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1006 select SPARSEMEM_STATIC if X86_32
1007 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1009 config ARCH_SELECT_MEMORY_MODEL
1011 depends on ARCH_SPARSEMEM_ENABLE
1013 config ARCH_MEMORY_PROBE
1015 depends on MEMORY_HOTPLUG
1020 bool "Allocate 3rd-level pagetables from highmem"
1021 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1023 The VM uses one page table entry for each page of physical memory.
1024 For systems with a lot of RAM, this can be wasteful of precious
1025 low memory. Setting this option will put user-space page table
1026 entries in high memory.
1028 config MATH_EMULATION
1030 prompt "Math emulation" if X86_32
1032 Linux can emulate a math coprocessor (used for floating point
1033 operations) if you don't have one. 486DX and Pentium processors have
1034 a math coprocessor built in, 486SX and 386 do not, unless you added
1035 a 487DX or 387, respectively. (The messages during boot time can
1036 give you some hints here ["man dmesg"].) Everyone needs either a
1037 coprocessor or this emulation.
1039 If you don't have a math coprocessor, you need to say Y here; if you
1040 say Y here even though you have a coprocessor, the coprocessor will
1041 be used nevertheless. (This behavior can be changed with the kernel
1042 command line option "no387", which comes handy if your coprocessor
1043 is broken. Try "man bootparam" or see the documentation of your boot
1044 loader (lilo or loadlin) about how to pass options to the kernel at
1045 boot time.) This means that it is a good idea to say Y here if you
1046 intend to use this kernel on different machines.
1048 More information about the internals of the Linux math coprocessor
1049 emulation can be found in <file:arch/x86/math-emu/README>.
1051 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1052 kernel, it won't hurt.
1055 bool "MTRR (Memory Type Range Register) support"
1057 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1058 the Memory Type Range Registers (MTRRs) may be used to control
1059 processor access to memory ranges. This is most useful if you have
1060 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1061 allows bus write transfers to be combined into a larger transfer
1062 before bursting over the PCI/AGP bus. This can increase performance
1063 of image write operations 2.5 times or more. Saying Y here creates a
1064 /proc/mtrr file which may be used to manipulate your processor's
1065 MTRRs. Typically the X server should use this.
1067 This code has a reasonably generic interface so that similar
1068 control registers on other processors can be easily supported
1071 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1072 Registers (ARRs) which provide a similar functionality to MTRRs. For
1073 these, the ARRs are used to emulate the MTRRs.
1074 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1075 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1076 write-combining. All of these processors are supported by this code
1077 and it makes sense to say Y here if you have one of them.
1079 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1080 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1081 can lead to all sorts of problems, so it's good to say Y here.
1083 You can safely say Y even if your machine doesn't have MTRRs, you'll
1084 just add about 9 KB to your kernel.
1086 See <file:Documentation/mtrr.txt> for more information.
1090 prompt "x86 PAT support"
1093 Use PAT attributes to setup page level cache control.
1095 PATs are the modern equivalents of MTRRs and are much more
1096 flexible than MTRRs.
1098 Say N here if you see bootup problems (boot crash, boot hang,
1099 spontaneous reboots) or a non-working video driver.
1105 prompt "EFI runtime service support"
1108 This enables the kernel to use EFI runtime services that are
1109 available (such as the EFI variable services).
1111 This option is only useful on systems that have EFI firmware.
1112 In addition, you should use the latest ELILO loader available
1113 at <http://elilo.sourceforge.net> in order to take advantage
1114 of EFI runtime services. However, even with this option, the
1115 resultant kernel should continue to boot on existing non-EFI
1120 prompt "Enable kernel irq balancing"
1121 depends on X86_32 && SMP && X86_IO_APIC
1123 The default yes will allow the kernel to do irq load balancing.
1124 Saying no will keep the kernel from doing irq load balancing.
1128 prompt "Enable seccomp to safely compute untrusted bytecode"
1131 This kernel feature is useful for number crunching applications
1132 that may need to compute untrusted bytecode during their
1133 execution. By using pipes or other transports made available to
1134 the process as file descriptors supporting the read/write
1135 syscalls, it's possible to isolate those applications in
1136 their own address space using seccomp. Once seccomp is
1137 enabled via /proc/<pid>/seccomp, it cannot be disabled
1138 and the task is only allowed to execute a few safe syscalls
1139 defined by each seccomp mode.
1141 If unsure, say Y. Only embedded should say N here.
1143 config CC_STACKPROTECTOR
1144 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1145 depends on X86_64 && EXPERIMENTAL && BROKEN
1147 This option turns on the -fstack-protector GCC feature. This
1148 feature puts, at the beginning of critical functions, a canary
1149 value on the stack just before the return address, and validates
1150 the value just before actually returning. Stack based buffer
1151 overflows (that need to overwrite this return address) now also
1152 overwrite the canary, which gets detected and the attack is then
1153 neutralized via a kernel panic.
1155 This feature requires gcc version 4.2 or above, or a distribution
1156 gcc with the feature backported. Older versions are automatically
1157 detected and for those versions, this configuration option is ignored.
1159 config CC_STACKPROTECTOR_ALL
1160 bool "Use stack-protector for all functions"
1161 depends on CC_STACKPROTECTOR
1163 Normally, GCC only inserts the canary value protection for
1164 functions that use large-ish on-stack buffers. By enabling
1165 this option, GCC will be asked to do this for ALL functions.
1167 source kernel/Kconfig.hz
1170 bool "kexec system call"
1171 depends on X86_BIOS_REBOOT
1173 kexec is a system call that implements the ability to shutdown your
1174 current kernel, and to start another kernel. It is like a reboot
1175 but it is independent of the system firmware. And like a reboot
1176 you can start any kernel with it, not just Linux.
1178 The name comes from the similarity to the exec system call.
1180 It is an ongoing process to be certain the hardware in a machine
1181 is properly shutdown, so do not be surprised if this code does not
1182 initially work for you. It may help to enable device hotplugging
1183 support. As of this writing the exact hardware interface is
1184 strongly in flux, so no good recommendation can be made.
1187 bool "kernel crash dumps (EXPERIMENTAL)"
1188 depends on EXPERIMENTAL
1189 depends on X86_64 || (X86_32 && HIGHMEM)
1191 Generate crash dump after being started by kexec.
1192 This should be normally only set in special crash dump kernels
1193 which are loaded in the main kernel with kexec-tools into
1194 a specially reserved region and then later executed after
1195 a crash by kdump/kexec. The crash dump kernel must be compiled
1196 to a memory address not used by the main kernel or BIOS using
1197 PHYSICAL_START, or it must be built as a relocatable image
1198 (CONFIG_RELOCATABLE=y).
1199 For more details see Documentation/kdump/kdump.txt
1201 config PHYSICAL_START
1202 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1203 default "0x1000000" if X86_NUMAQ
1204 default "0x200000" if X86_64
1207 This gives the physical address where the kernel is loaded.
1209 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1210 bzImage will decompress itself to above physical address and
1211 run from there. Otherwise, bzImage will run from the address where
1212 it has been loaded by the boot loader and will ignore above physical
1215 In normal kdump cases one does not have to set/change this option
1216 as now bzImage can be compiled as a completely relocatable image
1217 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1218 address. This option is mainly useful for the folks who don't want
1219 to use a bzImage for capturing the crash dump and want to use a
1220 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1221 to be specifically compiled to run from a specific memory area
1222 (normally a reserved region) and this option comes handy.
1224 So if you are using bzImage for capturing the crash dump, leave
1225 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1226 Otherwise if you plan to use vmlinux for capturing the crash dump
1227 change this value to start of the reserved region (Typically 16MB
1228 0x1000000). In other words, it can be set based on the "X" value as
1229 specified in the "crashkernel=YM@XM" command line boot parameter
1230 passed to the panic-ed kernel. Typically this parameter is set as
1231 crashkernel=64M@16M. Please take a look at
1232 Documentation/kdump/kdump.txt for more details about crash dumps.
1234 Usage of bzImage for capturing the crash dump is recommended as
1235 one does not have to build two kernels. Same kernel can be used
1236 as production kernel and capture kernel. Above option should have
1237 gone away after relocatable bzImage support is introduced. But it
1238 is present because there are users out there who continue to use
1239 vmlinux for dump capture. This option should go away down the
1242 Don't change this unless you know what you are doing.
1245 bool "Build a relocatable kernel (EXPERIMENTAL)"
1246 depends on EXPERIMENTAL
1248 This builds a kernel image that retains relocation information
1249 so it can be loaded someplace besides the default 1MB.
1250 The relocations tend to make the kernel binary about 10% larger,
1251 but are discarded at runtime.
1253 One use is for the kexec on panic case where the recovery kernel
1254 must live at a different physical address than the primary
1257 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1258 it has been loaded at and the compile time physical address
1259 (CONFIG_PHYSICAL_START) is ignored.
1261 config PHYSICAL_ALIGN
1263 prompt "Alignment value to which kernel should be aligned" if X86_32
1264 default "0x100000" if X86_32
1265 default "0x200000" if X86_64
1266 range 0x2000 0x400000
1268 This value puts the alignment restrictions on physical address
1269 where kernel is loaded and run from. Kernel is compiled for an
1270 address which meets above alignment restriction.
1272 If bootloader loads the kernel at a non-aligned address and
1273 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1274 address aligned to above value and run from there.
1276 If bootloader loads the kernel at a non-aligned address and
1277 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1278 load address and decompress itself to the address it has been
1279 compiled for and run from there. The address for which kernel is
1280 compiled already meets above alignment restrictions. Hence the
1281 end result is that kernel runs from a physical address meeting
1282 above alignment restrictions.
1284 Don't change this unless you know what you are doing.
1287 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1288 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1290 Say Y here to experiment with turning CPUs off and on, and to
1291 enable suspend on SMP systems. CPUs can be controlled through
1292 /sys/devices/system/cpu.
1293 Say N if you want to disable CPU hotplug and don't need to
1298 prompt "Compat VDSO support"
1299 depends on X86_32 || IA32_EMULATION
1301 Map the 32-bit VDSO to the predictable old-style address too.
1303 Say N here if you are running a sufficiently recent glibc
1304 version (2.3.3 or later), to remove the high-mapped
1305 VDSO mapping and to exclusively use the randomized VDSO.
1311 config ARCH_ENABLE_MEMORY_HOTPLUG
1313 depends on X86_64 || (X86_32 && HIGHMEM)
1315 config HAVE_ARCH_EARLY_PFN_TO_NID
1319 menu "Power management options"
1320 depends on !X86_VOYAGER
1322 config ARCH_HIBERNATION_HEADER
1324 depends on X86_64 && HIBERNATION
1326 source "kernel/power/Kconfig"
1328 source "drivers/acpi/Kconfig"
1333 depends on APM || APM_MODULE
1336 tristate "APM (Advanced Power Management) BIOS support"
1337 depends on X86_32 && PM_SLEEP && !X86_VISWS
1339 APM is a BIOS specification for saving power using several different
1340 techniques. This is mostly useful for battery powered laptops with
1341 APM compliant BIOSes. If you say Y here, the system time will be
1342 reset after a RESUME operation, the /proc/apm device will provide
1343 battery status information, and user-space programs will receive
1344 notification of APM "events" (e.g. battery status change).
1346 If you select "Y" here, you can disable actual use of the APM
1347 BIOS by passing the "apm=off" option to the kernel at boot time.
1349 Note that the APM support is almost completely disabled for
1350 machines with more than one CPU.
1352 In order to use APM, you will need supporting software. For location
1353 and more information, read <file:Documentation/power/pm.txt> and the
1354 Battery Powered Linux mini-HOWTO, available from
1355 <http://www.tldp.org/docs.html#howto>.
1357 This driver does not spin down disk drives (see the hdparm(8)
1358 manpage ("man 8 hdparm") for that), and it doesn't turn off
1359 VESA-compliant "green" monitors.
1361 This driver does not support the TI 4000M TravelMate and the ACER
1362 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1363 desktop machines also don't have compliant BIOSes, and this driver
1364 may cause those machines to panic during the boot phase.
1366 Generally, if you don't have a battery in your machine, there isn't
1367 much point in using this driver and you should say N. If you get
1368 random kernel OOPSes or reboots that don't seem to be related to
1369 anything, try disabling/enabling this option (or disabling/enabling
1372 Some other things you should try when experiencing seemingly random,
1375 1) make sure that you have enough swap space and that it is
1377 2) pass the "no-hlt" option to the kernel
1378 3) switch on floating point emulation in the kernel and pass
1379 the "no387" option to the kernel
1380 4) pass the "floppy=nodma" option to the kernel
1381 5) pass the "mem=4M" option to the kernel (thereby disabling
1382 all but the first 4 MB of RAM)
1383 6) make sure that the CPU is not over clocked.
1384 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1385 8) disable the cache from your BIOS settings
1386 9) install a fan for the video card or exchange video RAM
1387 10) install a better fan for the CPU
1388 11) exchange RAM chips
1389 12) exchange the motherboard.
1391 To compile this driver as a module, choose M here: the
1392 module will be called apm.
1396 config APM_IGNORE_USER_SUSPEND
1397 bool "Ignore USER SUSPEND"
1399 This option will ignore USER SUSPEND requests. On machines with a
1400 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1401 series notebooks, it is necessary to say Y because of a BIOS bug.
1403 config APM_DO_ENABLE
1404 bool "Enable PM at boot time"
1406 Enable APM features at boot time. From page 36 of the APM BIOS
1407 specification: "When disabled, the APM BIOS does not automatically
1408 power manage devices, enter the Standby State, enter the Suspend
1409 State, or take power saving steps in response to CPU Idle calls."
1410 This driver will make CPU Idle calls when Linux is idle (unless this
1411 feature is turned off -- see "Do CPU IDLE calls", below). This
1412 should always save battery power, but more complicated APM features
1413 will be dependent on your BIOS implementation. You may need to turn
1414 this option off if your computer hangs at boot time when using APM
1415 support, or if it beeps continuously instead of suspending. Turn
1416 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1417 T400CDT. This is off by default since most machines do fine without
1421 bool "Make CPU Idle calls when idle"
1423 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1424 On some machines, this can activate improved power savings, such as
1425 a slowed CPU clock rate, when the machine is idle. These idle calls
1426 are made after the idle loop has run for some length of time (e.g.,
1427 333 mS). On some machines, this will cause a hang at boot time or
1428 whenever the CPU becomes idle. (On machines with more than one CPU,
1429 this option does nothing.)
1431 config APM_DISPLAY_BLANK
1432 bool "Enable console blanking using APM"
1434 Enable console blanking using the APM. Some laptops can use this to
1435 turn off the LCD backlight when the screen blanker of the Linux
1436 virtual console blanks the screen. Note that this is only used by
1437 the virtual console screen blanker, and won't turn off the backlight
1438 when using the X Window system. This also doesn't have anything to
1439 do with your VESA-compliant power-saving monitor. Further, this
1440 option doesn't work for all laptops -- it might not turn off your
1441 backlight at all, or it might print a lot of errors to the console,
1442 especially if you are using gpm.
1444 config APM_ALLOW_INTS
1445 bool "Allow interrupts during APM BIOS calls"
1447 Normally we disable external interrupts while we are making calls to
1448 the APM BIOS as a measure to lessen the effects of a badly behaving
1449 BIOS implementation. The BIOS should reenable interrupts if it
1450 needs to. Unfortunately, some BIOSes do not -- especially those in
1451 many of the newer IBM Thinkpads. If you experience hangs when you
1452 suspend, try setting this to Y. Otherwise, say N.
1454 config APM_REAL_MODE_POWER_OFF
1455 bool "Use real mode APM BIOS call to power off"
1457 Use real mode APM BIOS calls to switch off the computer. This is
1458 a work-around for a number of buggy BIOSes. Switch this option on if
1459 your computer crashes instead of powering off properly.
1463 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1465 source "drivers/cpuidle/Kconfig"
1470 menu "Bus options (PCI etc.)"
1473 bool "PCI support" if !X86_VISWS && !X86_VSMP
1474 depends on !X86_VOYAGER
1476 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1478 Find out whether you have a PCI motherboard. PCI is the name of a
1479 bus system, i.e. the way the CPU talks to the other stuff inside
1480 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1481 VESA. If you have PCI, say Y, otherwise N.
1484 prompt "PCI access mode"
1485 depends on X86_32 && PCI && !X86_VISWS
1488 On PCI systems, the BIOS can be used to detect the PCI devices and
1489 determine their configuration. However, some old PCI motherboards
1490 have BIOS bugs and may crash if this is done. Also, some embedded
1491 PCI-based systems don't have any BIOS at all. Linux can also try to
1492 detect the PCI hardware directly without using the BIOS.
1494 With this option, you can specify how Linux should detect the
1495 PCI devices. If you choose "BIOS", the BIOS will be used,
1496 if you choose "Direct", the BIOS won't be used, and if you
1497 choose "MMConfig", then PCI Express MMCONFIG will be used.
1498 If you choose "Any", the kernel will try MMCONFIG, then the
1499 direct access method and falls back to the BIOS if that doesn't
1500 work. If unsure, go with the default, which is "Any".
1505 config PCI_GOMMCONFIG
1522 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1524 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1527 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
1531 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1535 depends on PCI && PCI_GOOLPC
1543 bool "Support mmconfig PCI config space access"
1544 depends on X86_64 && PCI && ACPI
1547 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1548 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1550 DMA remapping (DMAR) devices support enables independent address
1551 translations for Direct Memory Access (DMA) from devices.
1552 These DMA remapping devices are reported via ACPI tables
1553 and include PCI device scope covered by these DMA
1558 prompt "Support for Graphics workaround"
1561 Current Graphics drivers tend to use physical address
1562 for DMA and avoid using DMA APIs. Setting this config
1563 option permits the IOMMU driver to set a unity map for
1564 all the OS-visible memory. Hence the driver can continue
1565 to use physical addresses for DMA.
1567 config DMAR_FLOPPY_WA
1571 Floppy disk drivers are know to bypass DMA API calls
1572 thereby failing to work when IOMMU is enabled. This
1573 workaround will setup a 1:1 mapping for the first
1574 16M to make floppy (an ISA device) work.
1576 source "drivers/pci/pcie/Kconfig"
1578 source "drivers/pci/Kconfig"
1580 # x86_64 have no ISA slots, but do have ISA-style DMA.
1588 depends on !(X86_VOYAGER || X86_VISWS)
1590 Find out whether you have ISA slots on your motherboard. ISA is the
1591 name of a bus system, i.e. the way the CPU talks to the other stuff
1592 inside your box. Other bus systems are PCI, EISA, MicroChannel
1593 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1594 newer boards don't support it. If you have ISA, say Y, otherwise N.
1600 The Extended Industry Standard Architecture (EISA) bus was
1601 developed as an open alternative to the IBM MicroChannel bus.
1603 The EISA bus provided some of the features of the IBM MicroChannel
1604 bus while maintaining backward compatibility with cards made for
1605 the older ISA bus. The EISA bus saw limited use between 1988 and
1606 1995 when it was made obsolete by the PCI bus.
1608 Say Y here if you are building a kernel for an EISA-based machine.
1612 source "drivers/eisa/Kconfig"
1615 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1616 default y if X86_VOYAGER
1618 MicroChannel Architecture is found in some IBM PS/2 machines and
1619 laptops. It is a bus system similar to PCI or ISA. See
1620 <file:Documentation/mca.txt> (and especially the web page given
1621 there) before attempting to build an MCA bus kernel.
1623 source "drivers/mca/Kconfig"
1626 tristate "NatSemi SCx200 support"
1627 depends on !X86_VOYAGER
1629 This provides basic support for National Semiconductor's
1630 (now AMD's) Geode processors. The driver probes for the
1631 PCI-IDs of several on-chip devices, so its a good dependency
1632 for other scx200_* drivers.
1634 If compiled as a module, the driver is named scx200.
1636 config SCx200HR_TIMER
1637 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1638 depends on SCx200 && GENERIC_TIME
1641 This driver provides a clocksource built upon the on-chip
1642 27MHz high-resolution timer. Its also a workaround for
1643 NSC Geode SC-1100's buggy TSC, which loses time when the
1644 processor goes idle (as is done by the scheduler). The
1645 other workaround is idle=poll boot option.
1647 config GEODE_MFGPT_TIMER
1649 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1650 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1652 This driver provides a clock event source based on the MFGPT
1653 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1654 MFGPTs have a better resolution and max interval than the
1655 generic PIT, and are suitable for use as high-res timers.
1658 bool "One Laptop Per Child support"
1661 Add support for detecting the unique features of the OLPC
1668 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1670 source "drivers/pcmcia/Kconfig"
1672 source "drivers/pci/hotplug/Kconfig"
1677 menu "Executable file formats / Emulations"
1679 source "fs/Kconfig.binfmt"
1681 config IA32_EMULATION
1682 bool "IA32 Emulation"
1684 select COMPAT_BINFMT_ELF
1686 Include code to run 32-bit programs under a 64-bit kernel. You should
1687 likely turn this on, unless you're 100% sure that you don't have any
1688 32-bit programs left.
1691 tristate "IA32 a.out support"
1692 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1694 Support old a.out binaries in the 32bit emulation.
1698 depends on IA32_EMULATION
1700 config COMPAT_FOR_U64_ALIGNMENT
1704 config SYSVIPC_COMPAT
1706 depends on X86_64 && COMPAT && SYSVIPC
1711 source "net/Kconfig"
1713 source "drivers/Kconfig"
1715 source "drivers/firmware/Kconfig"
1719 source "arch/x86/Kconfig.debug"
1721 source "security/Kconfig"
1723 source "crypto/Kconfig"
1725 source "arch/x86/kvm/Kconfig"
1727 source "lib/Kconfig"