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.
540 # need this always selected by IOMMU for the VIA workaround
544 Support for software bounce buffers used on x86-64 systems
545 which don't have a hardware IOMMU (e.g. the current generation
546 of Intel's x86-64 CPUs). Using this PCI devices which can only
547 access 32-bits of memory can be used on systems with more than
548 3 GB of memory. If unsure, say Y.
551 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
554 int "Maximum number of CPUs (2-255)"
557 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
560 This allows you to specify the maximum number of CPUs which this
561 kernel will support. The maximum supported value is 255 and the
562 minimum value which makes sense is 2.
564 This is purely to save memory - each supported CPU adds
565 approximately eight kilobytes to the kernel image.
568 bool "SMT (Hyperthreading) scheduler support"
571 SMT scheduler support improves the CPU scheduler's decision making
572 when dealing with Intel Pentium 4 chips with HyperThreading at a
573 cost of slightly increased overhead in some places. If unsure say
578 prompt "Multi-core scheduler support"
581 Multi-core scheduler support improves the CPU scheduler's decision
582 making when dealing with multi-core CPU chips at a cost of slightly
583 increased overhead in some places. If unsure say N here.
585 source "kernel/Kconfig.preempt"
588 bool "Local APIC support on uniprocessors"
589 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
591 A local APIC (Advanced Programmable Interrupt Controller) is an
592 integrated interrupt controller in the CPU. If you have a single-CPU
593 system which has a processor with a local APIC, you can say Y here to
594 enable and use it. If you say Y here even though your machine doesn't
595 have a local APIC, then the kernel will still run with no slowdown at
596 all. The local APIC supports CPU-generated self-interrupts (timer,
597 performance counters), and the NMI watchdog which detects hard
601 bool "IO-APIC support on uniprocessors"
602 depends on X86_UP_APIC
604 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
605 SMP-capable replacement for PC-style interrupt controllers. Most
606 SMP systems and many recent uniprocessor systems have one.
608 If you have a single-CPU system with an IO-APIC, you can say Y here
609 to use it. If you say Y here even though your machine doesn't have
610 an IO-APIC, then the kernel will still run with no slowdown at all.
612 config X86_LOCAL_APIC
614 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
618 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
620 config X86_VISWS_APIC
622 depends on X86_32 && X86_VISWS
625 bool "Machine Check Exception"
626 depends on !X86_VOYAGER
628 Machine Check Exception support allows the processor to notify the
629 kernel if it detects a problem (e.g. overheating, component failure).
630 The action the kernel takes depends on the severity of the problem,
631 ranging from a warning message on the console, to halting the machine.
632 Your processor must be a Pentium or newer to support this - check the
633 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
634 have a design flaw which leads to false MCE events - hence MCE is
635 disabled on all P5 processors, unless explicitly enabled with "mce"
636 as a boot argument. Similarly, if MCE is built in and creates a
637 problem on some new non-standard machine, you can boot with "nomce"
638 to disable it. MCE support simply ignores non-MCE processors like
639 the 386 and 486, so nearly everyone can say Y here.
643 prompt "Intel MCE features"
644 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
646 Additional support for intel specific MCE features such as
651 prompt "AMD MCE features"
652 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
654 Additional support for AMD specific MCE features such as
655 the DRAM Error Threshold.
657 config X86_MCE_NONFATAL
658 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
659 depends on X86_32 && X86_MCE
661 Enabling this feature starts a timer that triggers every 5 seconds which
662 will look at the machine check registers to see if anything happened.
663 Non-fatal problems automatically get corrected (but still logged).
664 Disable this if you don't want to see these messages.
665 Seeing the messages this option prints out may be indicative of dying
666 or out-of-spec (ie, overclocked) hardware.
667 This option only does something on certain CPUs.
668 (AMD Athlon/Duron and Intel Pentium 4)
670 config X86_MCE_P4THERMAL
671 bool "check for P4 thermal throttling interrupt."
672 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
674 Enabling this feature will cause a message to be printed when the P4
675 enters thermal throttling.
678 bool "Enable VM86 support" if EMBEDDED
682 This option is required by programs like DOSEMU to run 16-bit legacy
683 code on X86 processors. It also may be needed by software like
684 XFree86 to initialize some video cards via BIOS. Disabling this
685 option saves about 6k.
688 tristate "Toshiba Laptop support"
691 This adds a driver to safely access the System Management Mode of
692 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
693 not work on models with a Phoenix BIOS. The System Management Mode
694 is used to set the BIOS and power saving options on Toshiba portables.
696 For information on utilities to make use of this driver see the
697 Toshiba Linux utilities web site at:
698 <http://www.buzzard.org.uk/toshiba/>.
700 Say Y if you intend to run this kernel on a Toshiba portable.
704 tristate "Dell laptop support"
706 This adds a driver to safely access the System Management Mode
707 of the CPU on the Dell Inspiron 8000. The System Management Mode
708 is used to read cpu temperature and cooling fan status and to
709 control the fans on the I8K portables.
711 This driver has been tested only on the Inspiron 8000 but it may
712 also work with other Dell laptops. You can force loading on other
713 models by passing the parameter `force=1' to the module. Use at
716 For information on utilities to make use of this driver see the
717 I8K Linux utilities web site at:
718 <http://people.debian.org/~dz/i8k/>
720 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
723 config X86_REBOOTFIXUPS
725 prompt "Enable X86 board specific fixups for reboot"
726 depends on X86_32 && X86
728 This enables chipset and/or board specific fixups to be done
729 in order to get reboot to work correctly. This is only needed on
730 some combinations of hardware and BIOS. The symptom, for which
731 this config is intended, is when reboot ends with a stalled/hung
734 Currently, the only fixup is for the Geode machines using
735 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
737 Say Y if you want to enable the fixup. Currently, it's safe to
738 enable this option even if you don't need it.
742 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
745 If you say Y here, you will be able to update the microcode on
746 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
747 Pentium III, Pentium 4, Xeon etc. You will obviously need the
748 actual microcode binary data itself which is not shipped with the
751 For latest news and information on obtaining all the required
752 ingredients for this driver, check:
753 <http://www.urbanmyth.org/microcode/>.
755 To compile this driver as a module, choose M here: the
756 module will be called microcode.
758 config MICROCODE_OLD_INTERFACE
763 tristate "/dev/cpu/*/msr - Model-specific register support"
765 This device gives privileged processes access to the x86
766 Model-Specific Registers (MSRs). It is a character device with
767 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
768 MSR accesses are directed to a specific CPU on multi-processor
772 tristate "/dev/cpu/*/cpuid - CPU information support"
774 This device gives processes access to the x86 CPUID instruction to
775 be executed on a specific processor. It is a character device
776 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
780 prompt "High Memory Support"
781 default HIGHMEM4G if !X86_NUMAQ
782 default HIGHMEM64G if X86_NUMAQ
787 depends on !X86_NUMAQ
789 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
790 However, the address space of 32-bit x86 processors is only 4
791 Gigabytes large. That means that, if you have a large amount of
792 physical memory, not all of it can be "permanently mapped" by the
793 kernel. The physical memory that's not permanently mapped is called
796 If you are compiling a kernel which will never run on a machine with
797 more than 1 Gigabyte total physical RAM, answer "off" here (default
798 choice and suitable for most users). This will result in a "3GB/1GB"
799 split: 3GB are mapped so that each process sees a 3GB virtual memory
800 space and the remaining part of the 4GB virtual memory space is used
801 by the kernel to permanently map as much physical memory as
804 If the machine has between 1 and 4 Gigabytes physical RAM, then
807 If more than 4 Gigabytes is used then answer "64GB" here. This
808 selection turns Intel PAE (Physical Address Extension) mode on.
809 PAE implements 3-level paging on IA32 processors. PAE is fully
810 supported by Linux, PAE mode is implemented on all recent Intel
811 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
812 then the kernel will not boot on CPUs that don't support PAE!
814 The actual amount of total physical memory will either be
815 auto detected or can be forced by using a kernel command line option
816 such as "mem=256M". (Try "man bootparam" or see the documentation of
817 your boot loader (lilo or loadlin) about how to pass options to the
818 kernel at boot time.)
820 If unsure, say "off".
824 depends on !X86_NUMAQ
826 Select this if you have a 32-bit processor and between 1 and 4
827 gigabytes of physical RAM.
831 depends on !M386 && !M486
834 Select this if you have a 32-bit processor and more than 4
835 gigabytes of physical RAM.
840 depends on EXPERIMENTAL
841 prompt "Memory split" if EMBEDDED
845 Select the desired split between kernel and user memory.
847 If the address range available to the kernel is less than the
848 physical memory installed, the remaining memory will be available
849 as "high memory". Accessing high memory is a little more costly
850 than low memory, as it needs to be mapped into the kernel first.
851 Note that increasing the kernel address space limits the range
852 available to user programs, making the address space there
853 tighter. Selecting anything other than the default 3G/1G split
854 will also likely make your kernel incompatible with binary-only
857 If you are not absolutely sure what you are doing, leave this
861 bool "3G/1G user/kernel split"
862 config VMSPLIT_3G_OPT
864 bool "3G/1G user/kernel split (for full 1G low memory)"
866 bool "2G/2G user/kernel split"
867 config VMSPLIT_2G_OPT
869 bool "2G/2G user/kernel split (for full 2G low memory)"
871 bool "1G/3G user/kernel split"
876 default 0xB0000000 if VMSPLIT_3G_OPT
877 default 0x80000000 if VMSPLIT_2G
878 default 0x78000000 if VMSPLIT_2G_OPT
879 default 0x40000000 if VMSPLIT_1G
885 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
889 prompt "PAE (Physical Address Extension) Support"
890 depends on X86_32 && !HIGHMEM4G
891 select RESOURCES_64BIT
893 PAE is required for NX support, and furthermore enables
894 larger swapspace support for non-overcommit purposes. It
895 has the cost of more pagetable lookup overhead, and also
896 consumes more pagetable space per process.
898 # Common NUMA Features
900 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
902 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
904 default y if (X86_NUMAQ || X86_SUMMIT)
906 Enable NUMA (Non Uniform Memory Access) support.
907 The kernel will try to allocate memory used by a CPU on the
908 local memory controller of the CPU and add some more
909 NUMA awareness to the kernel.
911 For i386 this is currently highly experimental and should be only
912 used for kernel development. It might also cause boot failures.
913 For x86_64 this is recommended on all multiprocessor Opteron systems.
914 If the system is EM64T, you should say N unless your system is
917 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
918 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
922 prompt "Old style AMD Opteron NUMA detection"
923 depends on X86_64 && NUMA && PCI
925 Enable K8 NUMA node topology detection. You should say Y here if
926 you have a multi processor AMD K8 system. This uses an old
927 method to read the NUMA configuration directly from the builtin
928 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
929 instead, which also takes priority if both are compiled in.
931 config X86_64_ACPI_NUMA
933 prompt "ACPI NUMA detection"
934 depends on X86_64 && NUMA && ACPI && PCI
937 Enable ACPI SRAT based node topology detection.
939 # Some NUMA nodes have memory ranges that span
940 # other nodes. Even though a pfn is valid and
941 # between a node's start and end pfns, it may not
942 # reside on that node. See memmap_init_zone()
944 config NODES_SPAN_OTHER_NODES
946 depends on X86_64_ACPI_NUMA
949 bool "NUMA emulation"
950 depends on X86_64 && NUMA
952 Enable NUMA emulation. A flat machine will be split
953 into virtual nodes when booted with "numa=fake=N", where N is the
954 number of nodes. This is only useful for debugging.
957 int "Max num nodes shift(1-15)"
959 default "6" if X86_64
960 default "4" if X86_NUMAQ
962 depends on NEED_MULTIPLE_NODES
964 config HAVE_ARCH_BOOTMEM_NODE
966 depends on X86_32 && NUMA
968 config ARCH_HAVE_MEMORY_PRESENT
970 depends on X86_32 && DISCONTIGMEM
972 config NEED_NODE_MEMMAP_SIZE
974 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
976 config HAVE_ARCH_ALLOC_REMAP
978 depends on X86_32 && NUMA
980 config ARCH_FLATMEM_ENABLE
982 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
984 config ARCH_DISCONTIGMEM_ENABLE
986 depends on NUMA && X86_32
988 config ARCH_DISCONTIGMEM_DEFAULT
990 depends on NUMA && X86_32
992 config ARCH_SPARSEMEM_DEFAULT
996 config ARCH_SPARSEMEM_ENABLE
998 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
999 select SPARSEMEM_STATIC if X86_32
1000 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1002 config ARCH_SELECT_MEMORY_MODEL
1004 depends on ARCH_SPARSEMEM_ENABLE
1006 config ARCH_MEMORY_PROBE
1008 depends on MEMORY_HOTPLUG
1013 bool "Allocate 3rd-level pagetables from highmem"
1014 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1016 The VM uses one page table entry for each page of physical memory.
1017 For systems with a lot of RAM, this can be wasteful of precious
1018 low memory. Setting this option will put user-space page table
1019 entries in high memory.
1021 config MATH_EMULATION
1023 prompt "Math emulation" if X86_32
1025 Linux can emulate a math coprocessor (used for floating point
1026 operations) if you don't have one. 486DX and Pentium processors have
1027 a math coprocessor built in, 486SX and 386 do not, unless you added
1028 a 487DX or 387, respectively. (The messages during boot time can
1029 give you some hints here ["man dmesg"].) Everyone needs either a
1030 coprocessor or this emulation.
1032 If you don't have a math coprocessor, you need to say Y here; if you
1033 say Y here even though you have a coprocessor, the coprocessor will
1034 be used nevertheless. (This behavior can be changed with the kernel
1035 command line option "no387", which comes handy if your coprocessor
1036 is broken. Try "man bootparam" or see the documentation of your boot
1037 loader (lilo or loadlin) about how to pass options to the kernel at
1038 boot time.) This means that it is a good idea to say Y here if you
1039 intend to use this kernel on different machines.
1041 More information about the internals of the Linux math coprocessor
1042 emulation can be found in <file:arch/x86/math-emu/README>.
1044 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1045 kernel, it won't hurt.
1048 bool "MTRR (Memory Type Range Register) support"
1050 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1051 the Memory Type Range Registers (MTRRs) may be used to control
1052 processor access to memory ranges. This is most useful if you have
1053 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1054 allows bus write transfers to be combined into a larger transfer
1055 before bursting over the PCI/AGP bus. This can increase performance
1056 of image write operations 2.5 times or more. Saying Y here creates a
1057 /proc/mtrr file which may be used to manipulate your processor's
1058 MTRRs. Typically the X server should use this.
1060 This code has a reasonably generic interface so that similar
1061 control registers on other processors can be easily supported
1064 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1065 Registers (ARRs) which provide a similar functionality to MTRRs. For
1066 these, the ARRs are used to emulate the MTRRs.
1067 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1068 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1069 write-combining. All of these processors are supported by this code
1070 and it makes sense to say Y here if you have one of them.
1072 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1073 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1074 can lead to all sorts of problems, so it's good to say Y here.
1076 You can safely say Y even if your machine doesn't have MTRRs, you'll
1077 just add about 9 KB to your kernel.
1079 See <file:Documentation/mtrr.txt> for more information.
1083 prompt "x86 PAT support"
1086 Use PAT attributes to setup page level cache control.
1088 PATs are the modern equivalents of MTRRs and are much more
1089 flexible than MTRRs.
1091 Say N here if you see bootup problems (boot crash, boot hang,
1092 spontaneous reboots) or a non-working video driver.
1098 prompt "EFI runtime service support"
1101 This enables the kernel to use EFI runtime services that are
1102 available (such as the EFI variable services).
1104 This option is only useful on systems that have EFI firmware.
1105 In addition, you should use the latest ELILO loader available
1106 at <http://elilo.sourceforge.net> in order to take advantage
1107 of EFI runtime services. However, even with this option, the
1108 resultant kernel should continue to boot on existing non-EFI
1113 prompt "Enable kernel irq balancing"
1114 depends on X86_32 && SMP && X86_IO_APIC
1116 The default yes will allow the kernel to do irq load balancing.
1117 Saying no will keep the kernel from doing irq load balancing.
1121 prompt "Enable seccomp to safely compute untrusted bytecode"
1124 This kernel feature is useful for number crunching applications
1125 that may need to compute untrusted bytecode during their
1126 execution. By using pipes or other transports made available to
1127 the process as file descriptors supporting the read/write
1128 syscalls, it's possible to isolate those applications in
1129 their own address space using seccomp. Once seccomp is
1130 enabled via /proc/<pid>/seccomp, it cannot be disabled
1131 and the task is only allowed to execute a few safe syscalls
1132 defined by each seccomp mode.
1134 If unsure, say Y. Only embedded should say N here.
1136 config CC_STACKPROTECTOR
1137 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1138 depends on X86_64 && EXPERIMENTAL && BROKEN
1140 This option turns on the -fstack-protector GCC feature. This
1141 feature puts, at the beginning of critical functions, a canary
1142 value on the stack just before the return address, and validates
1143 the value just before actually returning. Stack based buffer
1144 overflows (that need to overwrite this return address) now also
1145 overwrite the canary, which gets detected and the attack is then
1146 neutralized via a kernel panic.
1148 This feature requires gcc version 4.2 or above, or a distribution
1149 gcc with the feature backported. Older versions are automatically
1150 detected and for those versions, this configuration option is ignored.
1152 config CC_STACKPROTECTOR_ALL
1153 bool "Use stack-protector for all functions"
1154 depends on CC_STACKPROTECTOR
1156 Normally, GCC only inserts the canary value protection for
1157 functions that use large-ish on-stack buffers. By enabling
1158 this option, GCC will be asked to do this for ALL functions.
1160 source kernel/Kconfig.hz
1163 bool "kexec system call"
1164 depends on X86_64 || X86_BIOS_REBOOT
1166 kexec is a system call that implements the ability to shutdown your
1167 current kernel, and to start another kernel. It is like a reboot
1168 but it is independent of the system firmware. And like a reboot
1169 you can start any kernel with it, not just Linux.
1171 The name comes from the similarity to the exec system call.
1173 It is an ongoing process to be certain the hardware in a machine
1174 is properly shutdown, so do not be surprised if this code does not
1175 initially work for you. It may help to enable device hotplugging
1176 support. As of this writing the exact hardware interface is
1177 strongly in flux, so no good recommendation can be made.
1180 bool "kernel crash dumps (EXPERIMENTAL)"
1181 depends on EXPERIMENTAL
1182 depends on X86_64 || (X86_32 && HIGHMEM)
1184 Generate crash dump after being started by kexec.
1185 This should be normally only set in special crash dump kernels
1186 which are loaded in the main kernel with kexec-tools into
1187 a specially reserved region and then later executed after
1188 a crash by kdump/kexec. The crash dump kernel must be compiled
1189 to a memory address not used by the main kernel or BIOS using
1190 PHYSICAL_START, or it must be built as a relocatable image
1191 (CONFIG_RELOCATABLE=y).
1192 For more details see Documentation/kdump/kdump.txt
1194 config PHYSICAL_START
1195 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1196 default "0x1000000" if X86_NUMAQ
1197 default "0x200000" if X86_64
1200 This gives the physical address where the kernel is loaded.
1202 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1203 bzImage will decompress itself to above physical address and
1204 run from there. Otherwise, bzImage will run from the address where
1205 it has been loaded by the boot loader and will ignore above physical
1208 In normal kdump cases one does not have to set/change this option
1209 as now bzImage can be compiled as a completely relocatable image
1210 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1211 address. This option is mainly useful for the folks who don't want
1212 to use a bzImage for capturing the crash dump and want to use a
1213 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1214 to be specifically compiled to run from a specific memory area
1215 (normally a reserved region) and this option comes handy.
1217 So if you are using bzImage for capturing the crash dump, leave
1218 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1219 Otherwise if you plan to use vmlinux for capturing the crash dump
1220 change this value to start of the reserved region (Typically 16MB
1221 0x1000000). In other words, it can be set based on the "X" value as
1222 specified in the "crashkernel=YM@XM" command line boot parameter
1223 passed to the panic-ed kernel. Typically this parameter is set as
1224 crashkernel=64M@16M. Please take a look at
1225 Documentation/kdump/kdump.txt for more details about crash dumps.
1227 Usage of bzImage for capturing the crash dump is recommended as
1228 one does not have to build two kernels. Same kernel can be used
1229 as production kernel and capture kernel. Above option should have
1230 gone away after relocatable bzImage support is introduced. But it
1231 is present because there are users out there who continue to use
1232 vmlinux for dump capture. This option should go away down the
1235 Don't change this unless you know what you are doing.
1238 bool "Build a relocatable kernel (EXPERIMENTAL)"
1239 depends on EXPERIMENTAL
1241 This builds a kernel image that retains relocation information
1242 so it can be loaded someplace besides the default 1MB.
1243 The relocations tend to make the kernel binary about 10% larger,
1244 but are discarded at runtime.
1246 One use is for the kexec on panic case where the recovery kernel
1247 must live at a different physical address than the primary
1250 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1251 it has been loaded at and the compile time physical address
1252 (CONFIG_PHYSICAL_START) is ignored.
1254 config PHYSICAL_ALIGN
1256 prompt "Alignment value to which kernel should be aligned" if X86_32
1257 default "0x100000" if X86_32
1258 default "0x200000" if X86_64
1259 range 0x2000 0x400000
1261 This value puts the alignment restrictions on physical address
1262 where kernel is loaded and run from. Kernel is compiled for an
1263 address which meets above alignment restriction.
1265 If bootloader loads the kernel at a non-aligned address and
1266 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1267 address aligned to above value and run from there.
1269 If bootloader loads the kernel at a non-aligned address and
1270 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1271 load address and decompress itself to the address it has been
1272 compiled for and run from there. The address for which kernel is
1273 compiled already meets above alignment restrictions. Hence the
1274 end result is that kernel runs from a physical address meeting
1275 above alignment restrictions.
1277 Don't change this unless you know what you are doing.
1280 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1281 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1283 Say Y here to experiment with turning CPUs off and on, and to
1284 enable suspend on SMP systems. CPUs can be controlled through
1285 /sys/devices/system/cpu.
1286 Say N if you want to disable CPU hotplug and don't need to
1291 prompt "Compat VDSO support"
1292 depends on X86_32 || IA32_EMULATION
1294 Map the 32-bit VDSO to the predictable old-style address too.
1296 Say N here if you are running a sufficiently recent glibc
1297 version (2.3.3 or later), to remove the high-mapped
1298 VDSO mapping and to exclusively use the randomized VDSO.
1304 config ARCH_ENABLE_MEMORY_HOTPLUG
1306 depends on X86_64 || (X86_32 && HIGHMEM)
1308 config HAVE_ARCH_EARLY_PFN_TO_NID
1312 menu "Power management options"
1313 depends on !X86_VOYAGER
1315 config ARCH_HIBERNATION_HEADER
1317 depends on X86_64 && HIBERNATION
1319 source "kernel/power/Kconfig"
1321 source "drivers/acpi/Kconfig"
1326 depends on APM || APM_MODULE
1329 tristate "APM (Advanced Power Management) BIOS support"
1330 depends on X86_32 && PM_SLEEP && !X86_VISWS
1332 APM is a BIOS specification for saving power using several different
1333 techniques. This is mostly useful for battery powered laptops with
1334 APM compliant BIOSes. If you say Y here, the system time will be
1335 reset after a RESUME operation, the /proc/apm device will provide
1336 battery status information, and user-space programs will receive
1337 notification of APM "events" (e.g. battery status change).
1339 If you select "Y" here, you can disable actual use of the APM
1340 BIOS by passing the "apm=off" option to the kernel at boot time.
1342 Note that the APM support is almost completely disabled for
1343 machines with more than one CPU.
1345 In order to use APM, you will need supporting software. For location
1346 and more information, read <file:Documentation/power/pm.txt> and the
1347 Battery Powered Linux mini-HOWTO, available from
1348 <http://www.tldp.org/docs.html#howto>.
1350 This driver does not spin down disk drives (see the hdparm(8)
1351 manpage ("man 8 hdparm") for that), and it doesn't turn off
1352 VESA-compliant "green" monitors.
1354 This driver does not support the TI 4000M TravelMate and the ACER
1355 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1356 desktop machines also don't have compliant BIOSes, and this driver
1357 may cause those machines to panic during the boot phase.
1359 Generally, if you don't have a battery in your machine, there isn't
1360 much point in using this driver and you should say N. If you get
1361 random kernel OOPSes or reboots that don't seem to be related to
1362 anything, try disabling/enabling this option (or disabling/enabling
1365 Some other things you should try when experiencing seemingly random,
1368 1) make sure that you have enough swap space and that it is
1370 2) pass the "no-hlt" option to the kernel
1371 3) switch on floating point emulation in the kernel and pass
1372 the "no387" option to the kernel
1373 4) pass the "floppy=nodma" option to the kernel
1374 5) pass the "mem=4M" option to the kernel (thereby disabling
1375 all but the first 4 MB of RAM)
1376 6) make sure that the CPU is not over clocked.
1377 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1378 8) disable the cache from your BIOS settings
1379 9) install a fan for the video card or exchange video RAM
1380 10) install a better fan for the CPU
1381 11) exchange RAM chips
1382 12) exchange the motherboard.
1384 To compile this driver as a module, choose M here: the
1385 module will be called apm.
1389 config APM_IGNORE_USER_SUSPEND
1390 bool "Ignore USER SUSPEND"
1392 This option will ignore USER SUSPEND requests. On machines with a
1393 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1394 series notebooks, it is necessary to say Y because of a BIOS bug.
1396 config APM_DO_ENABLE
1397 bool "Enable PM at boot time"
1399 Enable APM features at boot time. From page 36 of the APM BIOS
1400 specification: "When disabled, the APM BIOS does not automatically
1401 power manage devices, enter the Standby State, enter the Suspend
1402 State, or take power saving steps in response to CPU Idle calls."
1403 This driver will make CPU Idle calls when Linux is idle (unless this
1404 feature is turned off -- see "Do CPU IDLE calls", below). This
1405 should always save battery power, but more complicated APM features
1406 will be dependent on your BIOS implementation. You may need to turn
1407 this option off if your computer hangs at boot time when using APM
1408 support, or if it beeps continuously instead of suspending. Turn
1409 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1410 T400CDT. This is off by default since most machines do fine without
1414 bool "Make CPU Idle calls when idle"
1416 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1417 On some machines, this can activate improved power savings, such as
1418 a slowed CPU clock rate, when the machine is idle. These idle calls
1419 are made after the idle loop has run for some length of time (e.g.,
1420 333 mS). On some machines, this will cause a hang at boot time or
1421 whenever the CPU becomes idle. (On machines with more than one CPU,
1422 this option does nothing.)
1424 config APM_DISPLAY_BLANK
1425 bool "Enable console blanking using APM"
1427 Enable console blanking using the APM. Some laptops can use this to
1428 turn off the LCD backlight when the screen blanker of the Linux
1429 virtual console blanks the screen. Note that this is only used by
1430 the virtual console screen blanker, and won't turn off the backlight
1431 when using the X Window system. This also doesn't have anything to
1432 do with your VESA-compliant power-saving monitor. Further, this
1433 option doesn't work for all laptops -- it might not turn off your
1434 backlight at all, or it might print a lot of errors to the console,
1435 especially if you are using gpm.
1437 config APM_ALLOW_INTS
1438 bool "Allow interrupts during APM BIOS calls"
1440 Normally we disable external interrupts while we are making calls to
1441 the APM BIOS as a measure to lessen the effects of a badly behaving
1442 BIOS implementation. The BIOS should reenable interrupts if it
1443 needs to. Unfortunately, some BIOSes do not -- especially those in
1444 many of the newer IBM Thinkpads. If you experience hangs when you
1445 suspend, try setting this to Y. Otherwise, say N.
1447 config APM_REAL_MODE_POWER_OFF
1448 bool "Use real mode APM BIOS call to power off"
1450 Use real mode APM BIOS calls to switch off the computer. This is
1451 a work-around for a number of buggy BIOSes. Switch this option on if
1452 your computer crashes instead of powering off properly.
1456 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1458 source "drivers/cpuidle/Kconfig"
1463 menu "Bus options (PCI etc.)"
1466 bool "PCI support" if !X86_VISWS && !X86_VSMP
1467 depends on !X86_VOYAGER
1469 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1471 Find out whether you have a PCI motherboard. PCI is the name of a
1472 bus system, i.e. the way the CPU talks to the other stuff inside
1473 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1474 VESA. If you have PCI, say Y, otherwise N.
1477 prompt "PCI access mode"
1478 depends on X86_32 && PCI && !X86_VISWS
1481 On PCI systems, the BIOS can be used to detect the PCI devices and
1482 determine their configuration. However, some old PCI motherboards
1483 have BIOS bugs and may crash if this is done. Also, some embedded
1484 PCI-based systems don't have any BIOS at all. Linux can also try to
1485 detect the PCI hardware directly without using the BIOS.
1487 With this option, you can specify how Linux should detect the
1488 PCI devices. If you choose "BIOS", the BIOS will be used,
1489 if you choose "Direct", the BIOS won't be used, and if you
1490 choose "MMConfig", then PCI Express MMCONFIG will be used.
1491 If you choose "Any", the kernel will try MMCONFIG, then the
1492 direct access method and falls back to the BIOS if that doesn't
1493 work. If unsure, go with the default, which is "Any".
1498 config PCI_GOMMCONFIG
1515 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1517 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1520 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
1524 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1528 depends on PCI && PCI_GOOLPC
1536 bool "Support mmconfig PCI config space access"
1537 depends on X86_64 && PCI && ACPI
1540 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1541 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1543 DMA remapping (DMAR) devices support enables independent address
1544 translations for Direct Memory Access (DMA) from devices.
1545 These DMA remapping devices are reported via ACPI tables
1546 and include PCI device scope covered by these DMA
1551 prompt "Support for Graphics workaround"
1554 Current Graphics drivers tend to use physical address
1555 for DMA and avoid using DMA APIs. Setting this config
1556 option permits the IOMMU driver to set a unity map for
1557 all the OS-visible memory. Hence the driver can continue
1558 to use physical addresses for DMA.
1560 config DMAR_FLOPPY_WA
1564 Floppy disk drivers are know to bypass DMA API calls
1565 thereby failing to work when IOMMU is enabled. This
1566 workaround will setup a 1:1 mapping for the first
1567 16M to make floppy (an ISA device) work.
1569 source "drivers/pci/pcie/Kconfig"
1571 source "drivers/pci/Kconfig"
1573 # x86_64 have no ISA slots, but do have ISA-style DMA.
1581 depends on !(X86_VOYAGER || X86_VISWS)
1583 Find out whether you have ISA slots on your motherboard. ISA is the
1584 name of a bus system, i.e. the way the CPU talks to the other stuff
1585 inside your box. Other bus systems are PCI, EISA, MicroChannel
1586 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1587 newer boards don't support it. If you have ISA, say Y, otherwise N.
1593 The Extended Industry Standard Architecture (EISA) bus was
1594 developed as an open alternative to the IBM MicroChannel bus.
1596 The EISA bus provided some of the features of the IBM MicroChannel
1597 bus while maintaining backward compatibility with cards made for
1598 the older ISA bus. The EISA bus saw limited use between 1988 and
1599 1995 when it was made obsolete by the PCI bus.
1601 Say Y here if you are building a kernel for an EISA-based machine.
1605 source "drivers/eisa/Kconfig"
1608 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1609 default y if X86_VOYAGER
1611 MicroChannel Architecture is found in some IBM PS/2 machines and
1612 laptops. It is a bus system similar to PCI or ISA. See
1613 <file:Documentation/mca.txt> (and especially the web page given
1614 there) before attempting to build an MCA bus kernel.
1616 source "drivers/mca/Kconfig"
1619 tristate "NatSemi SCx200 support"
1620 depends on !X86_VOYAGER
1622 This provides basic support for National Semiconductor's
1623 (now AMD's) Geode processors. The driver probes for the
1624 PCI-IDs of several on-chip devices, so its a good dependency
1625 for other scx200_* drivers.
1627 If compiled as a module, the driver is named scx200.
1629 config SCx200HR_TIMER
1630 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1631 depends on SCx200 && GENERIC_TIME
1634 This driver provides a clocksource built upon the on-chip
1635 27MHz high-resolution timer. Its also a workaround for
1636 NSC Geode SC-1100's buggy TSC, which loses time when the
1637 processor goes idle (as is done by the scheduler). The
1638 other workaround is idle=poll boot option.
1640 config GEODE_MFGPT_TIMER
1642 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1643 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1645 This driver provides a clock event source based on the MFGPT
1646 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1647 MFGPTs have a better resolution and max interval than the
1648 generic PIT, and are suitable for use as high-res timers.
1651 bool "One Laptop Per Child support"
1654 Add support for detecting the unique features of the OLPC
1661 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1663 source "drivers/pcmcia/Kconfig"
1665 source "drivers/pci/hotplug/Kconfig"
1670 menu "Executable file formats / Emulations"
1672 source "fs/Kconfig.binfmt"
1674 config IA32_EMULATION
1675 bool "IA32 Emulation"
1677 select COMPAT_BINFMT_ELF
1679 Include code to run 32-bit programs under a 64-bit kernel. You should
1680 likely turn this on, unless you're 100% sure that you don't have any
1681 32-bit programs left.
1684 tristate "IA32 a.out support"
1685 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1687 Support old a.out binaries in the 32bit emulation.
1691 depends on IA32_EMULATION
1693 config COMPAT_FOR_U64_ALIGNMENT
1697 config SYSVIPC_COMPAT
1699 depends on X86_64 && COMPAT && SYSVIPC
1704 source "net/Kconfig"
1706 source "drivers/Kconfig"
1708 source "drivers/firmware/Kconfig"
1712 source "arch/x86/Kconfig.debug"
1714 source "security/Kconfig"
1716 source "crypto/Kconfig"
1718 source "arch/x86/kvm/Kconfig"
1720 source "lib/Kconfig"
projects / linux-2.6 / blob