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
24 select HAVE_KRETPROBES
25 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
26 select HAVE_ARCH_KGDB if !X86_VOYAGER
29 config GENERIC_LOCKBREAK
35 config GENERIC_CMOS_UPDATE
38 config CLOCKSOURCE_WATCHDOG
41 config GENERIC_CLOCKEVENTS
44 config GENERIC_CLOCKEVENTS_BROADCAST
46 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
48 config LOCKDEP_SUPPORT
51 config STACKTRACE_SUPPORT
54 config HAVE_LATENCYTOP_SUPPORT
57 config FAST_CMPXCHG_LOCAL
70 config GENERIC_ISA_DMA
80 config GENERIC_HWEIGHT
86 config ARCH_MAY_HAVE_PC_FDC
89 config RWSEM_GENERIC_SPINLOCK
92 config RWSEM_XCHGADD_ALGORITHM
95 config ARCH_HAS_ILOG2_U32
98 config ARCH_HAS_ILOG2_U64
101 config ARCH_HAS_CPU_IDLE_WAIT
104 config GENERIC_CALIBRATE_DELAY
107 config GENERIC_TIME_VSYSCALL
111 config ARCH_HAS_CPU_RELAX
114 config ARCH_HAS_CACHE_LINE_SIZE
117 config HAVE_SETUP_PER_CPU_AREA
118 def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
120 config HAVE_CPUMASK_OF_CPU_MAP
123 config ARCH_HIBERNATION_POSSIBLE
125 depends on !SMP || !X86_VOYAGER
127 config ARCH_SUSPEND_POSSIBLE
129 depends on !X86_VOYAGER
135 config ARCH_POPULATES_NODE_MAP
142 config ARCH_SUPPORTS_AOUT
145 config ARCH_SUPPORTS_OPTIMIZED_INLINING
148 # Use the generic interrupt handling code in kernel/irq/:
149 config GENERIC_HARDIRQS
153 config GENERIC_IRQ_PROBE
157 config GENERIC_PENDING_IRQ
159 depends on GENERIC_HARDIRQS && SMP
164 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
169 depends on X86_32 && SMP
173 depends on X86_64 && SMP
178 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
181 config X86_BIOS_REBOOT
183 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
186 config X86_TRAMPOLINE
188 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
193 source "init/Kconfig"
195 menu "Processor type and features"
197 source "kernel/time/Kconfig"
200 bool "Symmetric multi-processing support"
202 This enables support for systems with more than one CPU. If you have
203 a system with only one CPU, like most personal computers, say N. If
204 you have a system with more than one CPU, say Y.
206 If you say N here, the kernel will run on single and multiprocessor
207 machines, but will use only one CPU of a multiprocessor machine. If
208 you say Y here, the kernel will run on many, but not all,
209 singleprocessor machines. On a singleprocessor machine, the kernel
210 will run faster if you say N here.
212 Note that if you say Y here and choose architecture "586" or
213 "Pentium" under "Processor family", the kernel will not work on 486
214 architectures. Similarly, multiprocessor kernels for the "PPro"
215 architecture may not work on all Pentium based boards.
217 People using multiprocessor machines who say Y here should also say
218 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
219 Management" code will be disabled if you say Y here.
221 See also <file:Documentation/i386/IO-APIC.txt>,
222 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
223 <http://www.tldp.org/docs.html#howto>.
225 If you don't know what to do here, say N.
228 prompt "Subarchitecture Type"
234 Choose this option if your computer is a standard PC or compatible.
240 Select this for an AMD Elan processor.
242 Do not use this option for K6/Athlon/Opteron processors!
244 If unsure, choose "PC-compatible" instead.
248 depends on X86_32 && (SMP || BROKEN)
250 Voyager is an MCA-based 32-way capable SMP architecture proprietary
251 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
255 If you do not specifically know you have a Voyager based machine,
256 say N here, otherwise the kernel you build will not be bootable.
259 bool "NUMAQ (IBM/Sequent)"
260 depends on SMP && X86_32
263 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
264 multiquad box. This changes the way that processors are bootstrapped,
265 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
266 You will need a new lynxer.elf file to flash your firmware with - send
267 email to <Martin.Bligh@us.ibm.com>.
270 bool "Summit/EXA (IBM x440)"
271 depends on X86_32 && SMP
273 This option is needed for IBM systems that use the Summit/EXA chipset.
274 In particular, it is needed for the x440.
276 If you don't have one of these computers, you should say N here.
277 If you want to build a NUMA kernel, you must select ACPI.
280 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
281 depends on X86_32 && SMP
283 This option is needed for the systems that have more than 8 CPUs
284 and if the system is not of any sub-arch type above.
286 If you don't have such a system, you should say N here.
289 bool "SGI 320/540 (Visual Workstation)"
292 The SGI Visual Workstation series is an IA32-based workstation
293 based on SGI systems chips with some legacy PC hardware attached.
295 Say Y here to create a kernel to run on the SGI 320 or 540.
297 A kernel compiled for the Visual Workstation will not run on PCs
298 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
300 config X86_GENERICARCH
301 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
304 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
305 It is intended for a generic binary kernel.
306 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
309 bool "Support for Unisys ES7000 IA32 series"
310 depends on X86_32 && SMP
312 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
313 supposed to run on an IA32-based Unisys ES7000 system.
314 Only choose this option if you have such a system, otherwise you
318 bool "RDC R-321x SoC"
321 select X86_REBOOTFIXUPS
326 This option is needed for RDC R-321x system-on-chip, also known
328 If you don't have one of these chips, you should say N here.
331 bool "Support for ScaleMP vSMP"
335 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
336 supposed to run on these EM64T-based machines. Only choose this option
337 if you have one of these machines.
341 config SCHED_NO_NO_OMIT_FRAME_POINTER
343 prompt "Single-depth WCHAN output"
346 Calculate simpler /proc/<PID>/wchan values. If this option
347 is disabled then wchan values will recurse back to the
348 caller function. This provides more accurate wchan values,
349 at the expense of slightly more scheduling overhead.
351 If in doubt, say "Y".
353 menuconfig PARAVIRT_GUEST
354 bool "Paravirtualized guest support"
356 Say Y here to get to see options related to running Linux under
357 various hypervisors. This option alone does not add any kernel code.
359 If you say N, all options in this submenu will be skipped and disabled.
363 source "arch/x86/xen/Kconfig"
366 bool "VMI Guest support"
369 depends on !(X86_VISWS || X86_VOYAGER)
371 VMI provides a paravirtualized interface to the VMware ESX server
372 (it could be used by other hypervisors in theory too, but is not
373 at the moment), by linking the kernel to a GPL-ed ROM module
374 provided by the hypervisor.
377 bool "KVM paravirtualized clock"
379 depends on !(X86_VISWS || X86_VOYAGER)
381 Turning on this option will allow you to run a paravirtualized clock
382 when running over the KVM hypervisor. Instead of relying on a PIT
383 (or probably other) emulation by the underlying device model, the host
384 provides the guest with timing infrastructure such as time of day, and
388 bool "KVM Guest support"
390 depends on !(X86_VISWS || X86_VOYAGER)
392 This option enables various optimizations for running under the KVM
395 source "arch/x86/lguest/Kconfig"
398 bool "Enable paravirtualization code"
399 depends on !(X86_VISWS || X86_VOYAGER)
401 This changes the kernel so it can modify itself when it is run
402 under a hypervisor, potentially improving performance significantly
403 over full virtualization. However, when run without a hypervisor
404 the kernel is theoretically slower and slightly larger.
408 config MEMTEST_BOOTPARAM
409 bool "Memtest boot parameter"
413 This option adds a kernel parameter 'memtest', which allows memtest
414 to be disabled at boot. If this option is selected, memtest
415 functionality can be disabled with memtest=0 on the kernel
416 command line. The purpose of this option is to allow a single
417 kernel image to be distributed with memtest built in, but not
420 If you are unsure how to answer this question, answer Y.
422 config MEMTEST_BOOTPARAM_VALUE
423 int "Memtest boot parameter default value (0-4)"
424 depends on MEMTEST_BOOTPARAM
428 This option sets the default value for the kernel parameter
429 'memtest', which allows memtest to be disabled at boot. If this
430 option is set to 0 (zero), the memtest kernel parameter will
431 default to 0, disabling memtest at bootup. If this option is
432 set to 4, the memtest kernel parameter will default to 4,
433 enabling memtest at bootup, and use that as pattern number.
435 If you are unsure how to answer this question, answer 0.
439 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
442 config HAVE_ARCH_PARSE_SRAT
446 config X86_SUMMIT_NUMA
448 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
450 config X86_CYCLONE_TIMER
452 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
454 config ES7000_CLUSTERED_APIC
456 depends on SMP && X86_ES7000 && MPENTIUMIII
458 source "arch/x86/Kconfig.cpu"
462 prompt "HPET Timer Support" if X86_32
464 Use the IA-PC HPET (High Precision Event Timer) to manage
465 time in preference to the PIT and RTC, if a HPET is
467 HPET is the next generation timer replacing legacy 8254s.
468 The HPET provides a stable time base on SMP
469 systems, unlike the TSC, but it is more expensive to access,
470 as it is off-chip. You can find the HPET spec at
471 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
473 You can safely choose Y here. However, HPET will only be
474 activated if the platform and the BIOS support this feature.
475 Otherwise the 8254 will be used for timing services.
477 Choose N to continue using the legacy 8254 timer.
479 config HPET_EMULATE_RTC
481 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
483 # Mark as embedded because too many people got it wrong.
484 # The code disables itself when not needed.
487 bool "Enable DMI scanning" if EMBEDDED
489 Enabled scanning of DMI to identify machine quirks. Say Y
490 here unless you have verified that your setup is not
491 affected by entries in the DMI blacklist. Required by PNP
495 bool "GART IOMMU support" if EMBEDDED
499 depends on X86_64 && PCI
501 Support for full DMA access of devices with 32bit memory access only
502 on systems with more than 3GB. This is usually needed for USB,
503 sound, many IDE/SATA chipsets and some other devices.
504 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
505 based hardware IOMMU and a software bounce buffer based IOMMU used
506 on Intel systems and as fallback.
507 The code is only active when needed (enough memory and limited
508 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
512 bool "IBM Calgary IOMMU support"
514 depends on X86_64 && PCI && EXPERIMENTAL
516 Support for hardware IOMMUs in IBM's xSeries x366 and x460
517 systems. Needed to run systems with more than 3GB of memory
518 properly with 32-bit PCI devices that do not support DAC
519 (Double Address Cycle). Calgary also supports bus level
520 isolation, where all DMAs pass through the IOMMU. This
521 prevents them from going anywhere except their intended
522 destination. This catches hard-to-find kernel bugs and
523 mis-behaving drivers and devices that do not use the DMA-API
524 properly to set up their DMA buffers. The IOMMU can be
525 turned off at boot time with the iommu=off parameter.
526 Normally the kernel will make the right choice by itself.
529 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
531 prompt "Should Calgary be enabled by default?"
532 depends on CALGARY_IOMMU
534 Should Calgary be enabled by default? if you choose 'y', Calgary
535 will be used (if it exists). If you choose 'n', Calgary will not be
536 used even if it exists. If you choose 'n' and would like to use
537 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
541 def_bool (CALGARY_IOMMU || GART_IOMMU)
543 # need this always selected by IOMMU for the VIA workaround
547 Support for software bounce buffers used on x86-64 systems
548 which don't have a hardware IOMMU (e.g. the current generation
549 of Intel's x86-64 CPUs). Using this PCI devices which can only
550 access 32-bits of memory can be used on systems with more than
551 3 GB of memory. If unsure, say Y.
555 int "Maximum number of CPUs (2-255)"
558 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
561 This allows you to specify the maximum number of CPUs which this
562 kernel will support. The maximum supported value is 255 and the
563 minimum value which makes sense is 2.
565 This is purely to save memory - each supported CPU adds
566 approximately eight kilobytes to the kernel image.
569 bool "SMT (Hyperthreading) scheduler support"
572 SMT scheduler support improves the CPU scheduler's decision making
573 when dealing with Intel Pentium 4 chips with HyperThreading at a
574 cost of slightly increased overhead in some places. If unsure say
579 prompt "Multi-core scheduler support"
582 Multi-core scheduler support improves the CPU scheduler's decision
583 making when dealing with multi-core CPU chips at a cost of slightly
584 increased overhead in some places. If unsure say N here.
586 source "kernel/Kconfig.preempt"
589 bool "Local APIC support on uniprocessors"
590 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
592 A local APIC (Advanced Programmable Interrupt Controller) is an
593 integrated interrupt controller in the CPU. If you have a single-CPU
594 system which has a processor with a local APIC, you can say Y here to
595 enable and use it. If you say Y here even though your machine doesn't
596 have a local APIC, then the kernel will still run with no slowdown at
597 all. The local APIC supports CPU-generated self-interrupts (timer,
598 performance counters), and the NMI watchdog which detects hard
602 bool "IO-APIC support on uniprocessors"
603 depends on X86_UP_APIC
605 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
606 SMP-capable replacement for PC-style interrupt controllers. Most
607 SMP systems and many recent uniprocessor systems have one.
609 If you have a single-CPU system with an IO-APIC, you can say Y here
610 to use it. If you say Y here even though your machine doesn't have
611 an IO-APIC, then the kernel will still run with no slowdown at all.
613 config X86_LOCAL_APIC
615 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
619 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
621 config X86_VISWS_APIC
623 depends on X86_32 && X86_VISWS
626 bool "Machine Check Exception"
627 depends on !X86_VOYAGER
629 Machine Check Exception support allows the processor to notify the
630 kernel if it detects a problem (e.g. overheating, component failure).
631 The action the kernel takes depends on the severity of the problem,
632 ranging from a warning message on the console, to halting the machine.
633 Your processor must be a Pentium or newer to support this - check the
634 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
635 have a design flaw which leads to false MCE events - hence MCE is
636 disabled on all P5 processors, unless explicitly enabled with "mce"
637 as a boot argument. Similarly, if MCE is built in and creates a
638 problem on some new non-standard machine, you can boot with "nomce"
639 to disable it. MCE support simply ignores non-MCE processors like
640 the 386 and 486, so nearly everyone can say Y here.
644 prompt "Intel MCE features"
645 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
647 Additional support for intel specific MCE features such as
652 prompt "AMD MCE features"
653 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
655 Additional support for AMD specific MCE features such as
656 the DRAM Error Threshold.
658 config X86_MCE_NONFATAL
659 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
660 depends on X86_32 && X86_MCE
662 Enabling this feature starts a timer that triggers every 5 seconds which
663 will look at the machine check registers to see if anything happened.
664 Non-fatal problems automatically get corrected (but still logged).
665 Disable this if you don't want to see these messages.
666 Seeing the messages this option prints out may be indicative of dying
667 or out-of-spec (ie, overclocked) hardware.
668 This option only does something on certain CPUs.
669 (AMD Athlon/Duron and Intel Pentium 4)
671 config X86_MCE_P4THERMAL
672 bool "check for P4 thermal throttling interrupt."
673 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
675 Enabling this feature will cause a message to be printed when the P4
676 enters thermal throttling.
679 bool "Enable VM86 support" if EMBEDDED
683 This option is required by programs like DOSEMU to run 16-bit legacy
684 code on X86 processors. It also may be needed by software like
685 XFree86 to initialize some video cards via BIOS. Disabling this
686 option saves about 6k.
689 tristate "Toshiba Laptop support"
692 This adds a driver to safely access the System Management Mode of
693 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
694 not work on models with a Phoenix BIOS. The System Management Mode
695 is used to set the BIOS and power saving options on Toshiba portables.
697 For information on utilities to make use of this driver see the
698 Toshiba Linux utilities web site at:
699 <http://www.buzzard.org.uk/toshiba/>.
701 Say Y if you intend to run this kernel on a Toshiba portable.
705 tristate "Dell laptop support"
707 This adds a driver to safely access the System Management Mode
708 of the CPU on the Dell Inspiron 8000. The System Management Mode
709 is used to read cpu temperature and cooling fan status and to
710 control the fans on the I8K portables.
712 This driver has been tested only on the Inspiron 8000 but it may
713 also work with other Dell laptops. You can force loading on other
714 models by passing the parameter `force=1' to the module. Use at
717 For information on utilities to make use of this driver see the
718 I8K Linux utilities web site at:
719 <http://people.debian.org/~dz/i8k/>
721 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
724 config X86_REBOOTFIXUPS
726 prompt "Enable X86 board specific fixups for reboot"
727 depends on X86_32 && X86
729 This enables chipset and/or board specific fixups to be done
730 in order to get reboot to work correctly. This is only needed on
731 some combinations of hardware and BIOS. The symptom, for which
732 this config is intended, is when reboot ends with a stalled/hung
735 Currently, the only fixup is for the Geode machines using
736 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
738 Say Y if you want to enable the fixup. Currently, it's safe to
739 enable this option even if you don't need it.
743 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
746 If you say Y here, you will be able to update the microcode on
747 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
748 Pentium III, Pentium 4, Xeon etc. You will obviously need the
749 actual microcode binary data itself which is not shipped with the
752 For latest news and information on obtaining all the required
753 ingredients for this driver, check:
754 <http://www.urbanmyth.org/microcode/>.
756 To compile this driver as a module, choose M here: the
757 module will be called microcode.
759 config MICROCODE_OLD_INTERFACE
764 tristate "/dev/cpu/*/msr - Model-specific register support"
766 This device gives privileged processes access to the x86
767 Model-Specific Registers (MSRs). It is a character device with
768 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
769 MSR accesses are directed to a specific CPU on multi-processor
773 tristate "/dev/cpu/*/cpuid - CPU information support"
775 This device gives processes access to the x86 CPUID instruction to
776 be executed on a specific processor. It is a character device
777 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
781 prompt "High Memory Support"
782 default HIGHMEM4G if !X86_NUMAQ
783 default HIGHMEM64G if X86_NUMAQ
788 depends on !X86_NUMAQ
790 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
791 However, the address space of 32-bit x86 processors is only 4
792 Gigabytes large. That means that, if you have a large amount of
793 physical memory, not all of it can be "permanently mapped" by the
794 kernel. The physical memory that's not permanently mapped is called
797 If you are compiling a kernel which will never run on a machine with
798 more than 1 Gigabyte total physical RAM, answer "off" here (default
799 choice and suitable for most users). This will result in a "3GB/1GB"
800 split: 3GB are mapped so that each process sees a 3GB virtual memory
801 space and the remaining part of the 4GB virtual memory space is used
802 by the kernel to permanently map as much physical memory as
805 If the machine has between 1 and 4 Gigabytes physical RAM, then
808 If more than 4 Gigabytes is used then answer "64GB" here. This
809 selection turns Intel PAE (Physical Address Extension) mode on.
810 PAE implements 3-level paging on IA32 processors. PAE is fully
811 supported by Linux, PAE mode is implemented on all recent Intel
812 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
813 then the kernel will not boot on CPUs that don't support PAE!
815 The actual amount of total physical memory will either be
816 auto detected or can be forced by using a kernel command line option
817 such as "mem=256M". (Try "man bootparam" or see the documentation of
818 your boot loader (lilo or loadlin) about how to pass options to the
819 kernel at boot time.)
821 If unsure, say "off".
825 depends on !X86_NUMAQ
827 Select this if you have a 32-bit processor and between 1 and 4
828 gigabytes of physical RAM.
832 depends on !M386 && !M486
835 Select this if you have a 32-bit processor and more than 4
836 gigabytes of physical RAM.
841 depends on EXPERIMENTAL
842 prompt "Memory split" if EMBEDDED
846 Select the desired split between kernel and user memory.
848 If the address range available to the kernel is less than the
849 physical memory installed, the remaining memory will be available
850 as "high memory". Accessing high memory is a little more costly
851 than low memory, as it needs to be mapped into the kernel first.
852 Note that increasing the kernel address space limits the range
853 available to user programs, making the address space there
854 tighter. Selecting anything other than the default 3G/1G split
855 will also likely make your kernel incompatible with binary-only
858 If you are not absolutely sure what you are doing, leave this
862 bool "3G/1G user/kernel split"
863 config VMSPLIT_3G_OPT
865 bool "3G/1G user/kernel split (for full 1G low memory)"
867 bool "2G/2G user/kernel split"
868 config VMSPLIT_2G_OPT
870 bool "2G/2G user/kernel split (for full 2G low memory)"
872 bool "1G/3G user/kernel split"
877 default 0xB0000000 if VMSPLIT_3G_OPT
878 default 0x80000000 if VMSPLIT_2G
879 default 0x78000000 if VMSPLIT_2G_OPT
880 default 0x40000000 if VMSPLIT_1G
886 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
890 prompt "PAE (Physical Address Extension) Support"
891 depends on X86_32 && !HIGHMEM4G
892 select RESOURCES_64BIT
894 PAE is required for NX support, and furthermore enables
895 larger swapspace support for non-overcommit purposes. It
896 has the cost of more pagetable lookup overhead, and also
897 consumes more pagetable space per process.
899 # Common NUMA Features
901 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
903 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
905 default y if (X86_NUMAQ || X86_SUMMIT)
907 Enable NUMA (Non Uniform Memory Access) support.
908 The kernel will try to allocate memory used by a CPU on the
909 local memory controller of the CPU and add some more
910 NUMA awareness to the kernel.
912 For i386 this is currently highly experimental and should be only
913 used for kernel development. It might also cause boot failures.
914 For x86_64 this is recommended on all multiprocessor Opteron systems.
915 If the system is EM64T, you should say N unless your system is
918 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
919 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
923 prompt "Old style AMD Opteron NUMA detection"
924 depends on X86_64 && NUMA && PCI
926 Enable K8 NUMA node topology detection. You should say Y here if
927 you have a multi processor AMD K8 system. This uses an old
928 method to read the NUMA configuration directly from the builtin
929 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
930 instead, which also takes priority if both are compiled in.
932 config X86_64_ACPI_NUMA
934 prompt "ACPI NUMA detection"
935 depends on X86_64 && NUMA && ACPI && PCI
938 Enable ACPI SRAT based node topology detection.
940 # Some NUMA nodes have memory ranges that span
941 # other nodes. Even though a pfn is valid and
942 # between a node's start and end pfns, it may not
943 # reside on that node. See memmap_init_zone()
945 config NODES_SPAN_OTHER_NODES
947 depends on X86_64_ACPI_NUMA
950 bool "NUMA emulation"
951 depends on X86_64 && NUMA
953 Enable NUMA emulation. A flat machine will be split
954 into virtual nodes when booted with "numa=fake=N", where N is the
955 number of nodes. This is only useful for debugging.
958 int "Max num nodes shift(1-15)"
960 default "6" if X86_64
961 default "4" if X86_NUMAQ
963 depends on NEED_MULTIPLE_NODES
965 config HAVE_ARCH_BOOTMEM_NODE
967 depends on X86_32 && NUMA
969 config ARCH_HAVE_MEMORY_PRESENT
971 depends on X86_32 && DISCONTIGMEM
973 config NEED_NODE_MEMMAP_SIZE
975 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
977 config HAVE_ARCH_ALLOC_REMAP
979 depends on X86_32 && NUMA
981 config ARCH_FLATMEM_ENABLE
983 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
985 config ARCH_DISCONTIGMEM_ENABLE
987 depends on NUMA && X86_32
989 config ARCH_DISCONTIGMEM_DEFAULT
991 depends on NUMA && X86_32
993 config ARCH_SPARSEMEM_DEFAULT
997 config ARCH_SPARSEMEM_ENABLE
999 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1000 select SPARSEMEM_STATIC if X86_32
1001 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1003 config ARCH_SELECT_MEMORY_MODEL
1005 depends on ARCH_SPARSEMEM_ENABLE
1007 config ARCH_MEMORY_PROBE
1009 depends on MEMORY_HOTPLUG
1014 bool "Allocate 3rd-level pagetables from highmem"
1015 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1017 The VM uses one page table entry for each page of physical memory.
1018 For systems with a lot of RAM, this can be wasteful of precious
1019 low memory. Setting this option will put user-space page table
1020 entries in high memory.
1022 config MATH_EMULATION
1024 prompt "Math emulation" if X86_32
1026 Linux can emulate a math coprocessor (used for floating point
1027 operations) if you don't have one. 486DX and Pentium processors have
1028 a math coprocessor built in, 486SX and 386 do not, unless you added
1029 a 487DX or 387, respectively. (The messages during boot time can
1030 give you some hints here ["man dmesg"].) Everyone needs either a
1031 coprocessor or this emulation.
1033 If you don't have a math coprocessor, you need to say Y here; if you
1034 say Y here even though you have a coprocessor, the coprocessor will
1035 be used nevertheless. (This behavior can be changed with the kernel
1036 command line option "no387", which comes handy if your coprocessor
1037 is broken. Try "man bootparam" or see the documentation of your boot
1038 loader (lilo or loadlin) about how to pass options to the kernel at
1039 boot time.) This means that it is a good idea to say Y here if you
1040 intend to use this kernel on different machines.
1042 More information about the internals of the Linux math coprocessor
1043 emulation can be found in <file:arch/x86/math-emu/README>.
1045 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1046 kernel, it won't hurt.
1049 bool "MTRR (Memory Type Range Register) support"
1051 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1052 the Memory Type Range Registers (MTRRs) may be used to control
1053 processor access to memory ranges. This is most useful if you have
1054 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1055 allows bus write transfers to be combined into a larger transfer
1056 before bursting over the PCI/AGP bus. This can increase performance
1057 of image write operations 2.5 times or more. Saying Y here creates a
1058 /proc/mtrr file which may be used to manipulate your processor's
1059 MTRRs. Typically the X server should use this.
1061 This code has a reasonably generic interface so that similar
1062 control registers on other processors can be easily supported
1065 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1066 Registers (ARRs) which provide a similar functionality to MTRRs. For
1067 these, the ARRs are used to emulate the MTRRs.
1068 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1069 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1070 write-combining. All of these processors are supported by this code
1071 and it makes sense to say Y here if you have one of them.
1073 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1074 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1075 can lead to all sorts of problems, so it's good to say Y here.
1077 You can safely say Y even if your machine doesn't have MTRRs, you'll
1078 just add about 9 KB to your kernel.
1080 See <file:Documentation/mtrr.txt> for more information.
1084 prompt "x86 PAT support"
1087 Use PAT attributes to setup page level cache control.
1089 PATs are the modern equivalents of MTRRs and are much more
1090 flexible than MTRRs.
1092 Say N here if you see bootup problems (boot crash, boot hang,
1093 spontaneous reboots) or a non-working video driver.
1099 prompt "EFI runtime service support"
1102 This enables the kernel to use EFI runtime services that are
1103 available (such as the EFI variable services).
1105 This option is only useful on systems that have EFI firmware.
1106 In addition, you should use the latest ELILO loader available
1107 at <http://elilo.sourceforge.net> in order to take advantage
1108 of EFI runtime services. However, even with this option, the
1109 resultant kernel should continue to boot on existing non-EFI
1114 prompt "Enable kernel irq balancing"
1115 depends on X86_32 && SMP && X86_IO_APIC
1117 The default yes will allow the kernel to do irq load balancing.
1118 Saying no will keep the kernel from doing irq load balancing.
1122 prompt "Enable seccomp to safely compute untrusted bytecode"
1125 This kernel feature is useful for number crunching applications
1126 that may need to compute untrusted bytecode during their
1127 execution. By using pipes or other transports made available to
1128 the process as file descriptors supporting the read/write
1129 syscalls, it's possible to isolate those applications in
1130 their own address space using seccomp. Once seccomp is
1131 enabled via /proc/<pid>/seccomp, it cannot be disabled
1132 and the task is only allowed to execute a few safe syscalls
1133 defined by each seccomp mode.
1135 If unsure, say Y. Only embedded should say N here.
1137 config CC_STACKPROTECTOR
1138 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1139 depends on X86_64 && EXPERIMENTAL && BROKEN
1141 This option turns on the -fstack-protector GCC feature. This
1142 feature puts, at the beginning of critical functions, a canary
1143 value on the stack just before the return address, and validates
1144 the value just before actually returning. Stack based buffer
1145 overflows (that need to overwrite this return address) now also
1146 overwrite the canary, which gets detected and the attack is then
1147 neutralized via a kernel panic.
1149 This feature requires gcc version 4.2 or above, or a distribution
1150 gcc with the feature backported. Older versions are automatically
1151 detected and for those versions, this configuration option is ignored.
1153 config CC_STACKPROTECTOR_ALL
1154 bool "Use stack-protector for all functions"
1155 depends on CC_STACKPROTECTOR
1157 Normally, GCC only inserts the canary value protection for
1158 functions that use large-ish on-stack buffers. By enabling
1159 this option, GCC will be asked to do this for ALL functions.
1161 source kernel/Kconfig.hz
1164 bool "kexec system call"
1165 depends on X86_64 || X86_BIOS_REBOOT
1167 kexec is a system call that implements the ability to shutdown your
1168 current kernel, and to start another kernel. It is like a reboot
1169 but it is independent of the system firmware. And like a reboot
1170 you can start any kernel with it, not just Linux.
1172 The name comes from the similarity to the exec system call.
1174 It is an ongoing process to be certain the hardware in a machine
1175 is properly shutdown, so do not be surprised if this code does not
1176 initially work for you. It may help to enable device hotplugging
1177 support. As of this writing the exact hardware interface is
1178 strongly in flux, so no good recommendation can be made.
1181 bool "kernel crash dumps (EXPERIMENTAL)"
1182 depends on EXPERIMENTAL
1183 depends on X86_64 || (X86_32 && HIGHMEM)
1185 Generate crash dump after being started by kexec.
1186 This should be normally only set in special crash dump kernels
1187 which are loaded in the main kernel with kexec-tools into
1188 a specially reserved region and then later executed after
1189 a crash by kdump/kexec. The crash dump kernel must be compiled
1190 to a memory address not used by the main kernel or BIOS using
1191 PHYSICAL_START, or it must be built as a relocatable image
1192 (CONFIG_RELOCATABLE=y).
1193 For more details see Documentation/kdump/kdump.txt
1195 config PHYSICAL_START
1196 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1197 default "0x1000000" if X86_NUMAQ
1198 default "0x200000" if X86_64
1201 This gives the physical address where the kernel is loaded.
1203 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1204 bzImage will decompress itself to above physical address and
1205 run from there. Otherwise, bzImage will run from the address where
1206 it has been loaded by the boot loader and will ignore above physical
1209 In normal kdump cases one does not have to set/change this option
1210 as now bzImage can be compiled as a completely relocatable image
1211 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1212 address. This option is mainly useful for the folks who don't want
1213 to use a bzImage for capturing the crash dump and want to use a
1214 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1215 to be specifically compiled to run from a specific memory area
1216 (normally a reserved region) and this option comes handy.
1218 So if you are using bzImage for capturing the crash dump, leave
1219 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1220 Otherwise if you plan to use vmlinux for capturing the crash dump
1221 change this value to start of the reserved region (Typically 16MB
1222 0x1000000). In other words, it can be set based on the "X" value as
1223 specified in the "crashkernel=YM@XM" command line boot parameter
1224 passed to the panic-ed kernel. Typically this parameter is set as
1225 crashkernel=64M@16M. Please take a look at
1226 Documentation/kdump/kdump.txt for more details about crash dumps.
1228 Usage of bzImage for capturing the crash dump is recommended as
1229 one does not have to build two kernels. Same kernel can be used
1230 as production kernel and capture kernel. Above option should have
1231 gone away after relocatable bzImage support is introduced. But it
1232 is present because there are users out there who continue to use
1233 vmlinux for dump capture. This option should go away down the
1236 Don't change this unless you know what you are doing.
1239 bool "Build a relocatable kernel (EXPERIMENTAL)"
1240 depends on EXPERIMENTAL
1242 This builds a kernel image that retains relocation information
1243 so it can be loaded someplace besides the default 1MB.
1244 The relocations tend to make the kernel binary about 10% larger,
1245 but are discarded at runtime.
1247 One use is for the kexec on panic case where the recovery kernel
1248 must live at a different physical address than the primary
1251 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1252 it has been loaded at and the compile time physical address
1253 (CONFIG_PHYSICAL_START) is ignored.
1255 config PHYSICAL_ALIGN
1257 prompt "Alignment value to which kernel should be aligned" if X86_32
1258 default "0x100000" if X86_32
1259 default "0x200000" if X86_64
1260 range 0x2000 0x400000
1262 This value puts the alignment restrictions on physical address
1263 where kernel is loaded and run from. Kernel is compiled for an
1264 address which meets above alignment restriction.
1266 If bootloader loads the kernel at a non-aligned address and
1267 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1268 address aligned to above value and run from there.
1270 If bootloader loads the kernel at a non-aligned address and
1271 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1272 load address and decompress itself to the address it has been
1273 compiled for and run from there. The address for which kernel is
1274 compiled already meets above alignment restrictions. Hence the
1275 end result is that kernel runs from a physical address meeting
1276 above alignment restrictions.
1278 Don't change this unless you know what you are doing.
1281 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1282 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1284 Say Y here to experiment with turning CPUs off and on, and to
1285 enable suspend on SMP systems. CPUs can be controlled through
1286 /sys/devices/system/cpu.
1287 Say N if you want to disable CPU hotplug and don't need to
1292 prompt "Compat VDSO support"
1293 depends on X86_32 || IA32_EMULATION
1295 Map the 32-bit VDSO to the predictable old-style address too.
1297 Say N here if you are running a sufficiently recent glibc
1298 version (2.3.3 or later), to remove the high-mapped
1299 VDSO mapping and to exclusively use the randomized VDSO.
1305 config ARCH_ENABLE_MEMORY_HOTPLUG
1307 depends on X86_64 || (X86_32 && HIGHMEM)
1309 config HAVE_ARCH_EARLY_PFN_TO_NID
1313 menu "Power management options"
1314 depends on !X86_VOYAGER
1316 config ARCH_HIBERNATION_HEADER
1318 depends on X86_64 && HIBERNATION
1320 source "kernel/power/Kconfig"
1322 source "drivers/acpi/Kconfig"
1327 depends on APM || APM_MODULE
1330 tristate "APM (Advanced Power Management) BIOS support"
1331 depends on X86_32 && PM_SLEEP && !X86_VISWS
1333 APM is a BIOS specification for saving power using several different
1334 techniques. This is mostly useful for battery powered laptops with
1335 APM compliant BIOSes. If you say Y here, the system time will be
1336 reset after a RESUME operation, the /proc/apm device will provide
1337 battery status information, and user-space programs will receive
1338 notification of APM "events" (e.g. battery status change).
1340 If you select "Y" here, you can disable actual use of the APM
1341 BIOS by passing the "apm=off" option to the kernel at boot time.
1343 Note that the APM support is almost completely disabled for
1344 machines with more than one CPU.
1346 In order to use APM, you will need supporting software. For location
1347 and more information, read <file:Documentation/power/pm.txt> and the
1348 Battery Powered Linux mini-HOWTO, available from
1349 <http://www.tldp.org/docs.html#howto>.
1351 This driver does not spin down disk drives (see the hdparm(8)
1352 manpage ("man 8 hdparm") for that), and it doesn't turn off
1353 VESA-compliant "green" monitors.
1355 This driver does not support the TI 4000M TravelMate and the ACER
1356 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1357 desktop machines also don't have compliant BIOSes, and this driver
1358 may cause those machines to panic during the boot phase.
1360 Generally, if you don't have a battery in your machine, there isn't
1361 much point in using this driver and you should say N. If you get
1362 random kernel OOPSes or reboots that don't seem to be related to
1363 anything, try disabling/enabling this option (or disabling/enabling
1366 Some other things you should try when experiencing seemingly random,
1369 1) make sure that you have enough swap space and that it is
1371 2) pass the "no-hlt" option to the kernel
1372 3) switch on floating point emulation in the kernel and pass
1373 the "no387" option to the kernel
1374 4) pass the "floppy=nodma" option to the kernel
1375 5) pass the "mem=4M" option to the kernel (thereby disabling
1376 all but the first 4 MB of RAM)
1377 6) make sure that the CPU is not over clocked.
1378 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1379 8) disable the cache from your BIOS settings
1380 9) install a fan for the video card or exchange video RAM
1381 10) install a better fan for the CPU
1382 11) exchange RAM chips
1383 12) exchange the motherboard.
1385 To compile this driver as a module, choose M here: the
1386 module will be called apm.
1390 config APM_IGNORE_USER_SUSPEND
1391 bool "Ignore USER SUSPEND"
1393 This option will ignore USER SUSPEND requests. On machines with a
1394 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1395 series notebooks, it is necessary to say Y because of a BIOS bug.
1397 config APM_DO_ENABLE
1398 bool "Enable PM at boot time"
1400 Enable APM features at boot time. From page 36 of the APM BIOS
1401 specification: "When disabled, the APM BIOS does not automatically
1402 power manage devices, enter the Standby State, enter the Suspend
1403 State, or take power saving steps in response to CPU Idle calls."
1404 This driver will make CPU Idle calls when Linux is idle (unless this
1405 feature is turned off -- see "Do CPU IDLE calls", below). This
1406 should always save battery power, but more complicated APM features
1407 will be dependent on your BIOS implementation. You may need to turn
1408 this option off if your computer hangs at boot time when using APM
1409 support, or if it beeps continuously instead of suspending. Turn
1410 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1411 T400CDT. This is off by default since most machines do fine without
1415 bool "Make CPU Idle calls when idle"
1417 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1418 On some machines, this can activate improved power savings, such as
1419 a slowed CPU clock rate, when the machine is idle. These idle calls
1420 are made after the idle loop has run for some length of time (e.g.,
1421 333 mS). On some machines, this will cause a hang at boot time or
1422 whenever the CPU becomes idle. (On machines with more than one CPU,
1423 this option does nothing.)
1425 config APM_DISPLAY_BLANK
1426 bool "Enable console blanking using APM"
1428 Enable console blanking using the APM. Some laptops can use this to
1429 turn off the LCD backlight when the screen blanker of the Linux
1430 virtual console blanks the screen. Note that this is only used by
1431 the virtual console screen blanker, and won't turn off the backlight
1432 when using the X Window system. This also doesn't have anything to
1433 do with your VESA-compliant power-saving monitor. Further, this
1434 option doesn't work for all laptops -- it might not turn off your
1435 backlight at all, or it might print a lot of errors to the console,
1436 especially if you are using gpm.
1438 config APM_ALLOW_INTS
1439 bool "Allow interrupts during APM BIOS calls"
1441 Normally we disable external interrupts while we are making calls to
1442 the APM BIOS as a measure to lessen the effects of a badly behaving
1443 BIOS implementation. The BIOS should reenable interrupts if it
1444 needs to. Unfortunately, some BIOSes do not -- especially those in
1445 many of the newer IBM Thinkpads. If you experience hangs when you
1446 suspend, try setting this to Y. Otherwise, say N.
1448 config APM_REAL_MODE_POWER_OFF
1449 bool "Use real mode APM BIOS call to power off"
1451 Use real mode APM BIOS calls to switch off the computer. This is
1452 a work-around for a number of buggy BIOSes. Switch this option on if
1453 your computer crashes instead of powering off properly.
1457 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1459 source "drivers/cpuidle/Kconfig"
1464 menu "Bus options (PCI etc.)"
1467 bool "PCI support" if !X86_VISWS && !X86_VSMP
1468 depends on !X86_VOYAGER
1470 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1472 Find out whether you have a PCI motherboard. PCI is the name of a
1473 bus system, i.e. the way the CPU talks to the other stuff inside
1474 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1475 VESA. If you have PCI, say Y, otherwise N.
1478 prompt "PCI access mode"
1479 depends on X86_32 && PCI && !X86_VISWS
1482 On PCI systems, the BIOS can be used to detect the PCI devices and
1483 determine their configuration. However, some old PCI motherboards
1484 have BIOS bugs and may crash if this is done. Also, some embedded
1485 PCI-based systems don't have any BIOS at all. Linux can also try to
1486 detect the PCI hardware directly without using the BIOS.
1488 With this option, you can specify how Linux should detect the
1489 PCI devices. If you choose "BIOS", the BIOS will be used,
1490 if you choose "Direct", the BIOS won't be used, and if you
1491 choose "MMConfig", then PCI Express MMCONFIG will be used.
1492 If you choose "Any", the kernel will try MMCONFIG, then the
1493 direct access method and falls back to the BIOS if that doesn't
1494 work. If unsure, go with the default, which is "Any".
1499 config PCI_GOMMCONFIG
1512 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1514 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1517 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1521 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1528 bool "Support mmconfig PCI config space access"
1529 depends on X86_64 && PCI && ACPI
1532 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1533 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1535 DMA remapping (DMAR) devices support enables independent address
1536 translations for Direct Memory Access (DMA) from devices.
1537 These DMA remapping devices are reported via ACPI tables
1538 and include PCI device scope covered by these DMA
1543 prompt "Support for Graphics workaround"
1546 Current Graphics drivers tend to use physical address
1547 for DMA and avoid using DMA APIs. Setting this config
1548 option permits the IOMMU driver to set a unity map for
1549 all the OS-visible memory. Hence the driver can continue
1550 to use physical addresses for DMA.
1552 config DMAR_FLOPPY_WA
1556 Floppy disk drivers are know to bypass DMA API calls
1557 thereby failing to work when IOMMU is enabled. This
1558 workaround will setup a 1:1 mapping for the first
1559 16M to make floppy (an ISA device) work.
1561 source "drivers/pci/pcie/Kconfig"
1563 source "drivers/pci/Kconfig"
1565 # x86_64 have no ISA slots, but do have ISA-style DMA.
1573 depends on !(X86_VOYAGER || X86_VISWS)
1575 Find out whether you have ISA slots on your motherboard. ISA is the
1576 name of a bus system, i.e. the way the CPU talks to the other stuff
1577 inside your box. Other bus systems are PCI, EISA, MicroChannel
1578 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1579 newer boards don't support it. If you have ISA, say Y, otherwise N.
1585 The Extended Industry Standard Architecture (EISA) bus was
1586 developed as an open alternative to the IBM MicroChannel bus.
1588 The EISA bus provided some of the features of the IBM MicroChannel
1589 bus while maintaining backward compatibility with cards made for
1590 the older ISA bus. The EISA bus saw limited use between 1988 and
1591 1995 when it was made obsolete by the PCI bus.
1593 Say Y here if you are building a kernel for an EISA-based machine.
1597 source "drivers/eisa/Kconfig"
1600 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1601 default y if X86_VOYAGER
1603 MicroChannel Architecture is found in some IBM PS/2 machines and
1604 laptops. It is a bus system similar to PCI or ISA. See
1605 <file:Documentation/mca.txt> (and especially the web page given
1606 there) before attempting to build an MCA bus kernel.
1608 source "drivers/mca/Kconfig"
1611 tristate "NatSemi SCx200 support"
1612 depends on !X86_VOYAGER
1614 This provides basic support for National Semiconductor's
1615 (now AMD's) Geode processors. The driver probes for the
1616 PCI-IDs of several on-chip devices, so its a good dependency
1617 for other scx200_* drivers.
1619 If compiled as a module, the driver is named scx200.
1621 config SCx200HR_TIMER
1622 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1623 depends on SCx200 && GENERIC_TIME
1626 This driver provides a clocksource built upon the on-chip
1627 27MHz high-resolution timer. Its also a workaround for
1628 NSC Geode SC-1100's buggy TSC, which loses time when the
1629 processor goes idle (as is done by the scheduler). The
1630 other workaround is idle=poll boot option.
1632 config GEODE_MFGPT_TIMER
1634 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1635 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1637 This driver provides a clock event source based on the MFGPT
1638 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1639 MFGPTs have a better resolution and max interval than the
1640 generic PIT, and are suitable for use as high-res timers.
1646 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1648 source "drivers/pcmcia/Kconfig"
1650 source "drivers/pci/hotplug/Kconfig"
1655 menu "Executable file formats / Emulations"
1657 source "fs/Kconfig.binfmt"
1659 config IA32_EMULATION
1660 bool "IA32 Emulation"
1662 select COMPAT_BINFMT_ELF
1664 Include code to run 32-bit programs under a 64-bit kernel. You should
1665 likely turn this on, unless you're 100% sure that you don't have any
1666 32-bit programs left.
1669 tristate "IA32 a.out support"
1670 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1672 Support old a.out binaries in the 32bit emulation.
1676 depends on IA32_EMULATION
1678 config COMPAT_FOR_U64_ALIGNMENT
1682 config SYSVIPC_COMPAT
1684 depends on X86_64 && COMPAT && SYSVIPC
1689 source "net/Kconfig"
1691 source "drivers/Kconfig"
1693 source "drivers/firmware/Kconfig"
1697 source "arch/x86/Kconfig.debug"
1699 source "security/Kconfig"
1701 source "crypto/Kconfig"
1703 source "arch/x86/kvm/Kconfig"
1705 source "lib/Kconfig"
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