2 mainmenu "Linux Kernel Configuration for x86"
6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
9 Say yes to build a 64-bit kernel - formerly known as x86_64
10 Say no to build a 32-bit kernel - formerly known as i386
21 select HAVE_UNSTABLE_SCHED_CLOCK
25 select HAVE_KRETPROBES
26 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
27 select HAVE_ARCH_KGDB if !X86_VOYAGER
31 default "arch/x86/configs/i386_defconfig" if X86_32
32 default "arch/x86/configs/x86_64_defconfig" if X86_64
35 config GENERIC_LOCKBREAK
41 config GENERIC_CMOS_UPDATE
44 config CLOCKSOURCE_WATCHDOG
47 config GENERIC_CLOCKEVENTS
50 config GENERIC_CLOCKEVENTS_BROADCAST
52 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
54 config LOCKDEP_SUPPORT
57 config STACKTRACE_SUPPORT
60 config HAVE_LATENCYTOP_SUPPORT
63 config FAST_CMPXCHG_LOCAL
76 config GENERIC_ISA_DMA
86 config GENERIC_HWEIGHT
92 config ARCH_MAY_HAVE_PC_FDC
95 config RWSEM_GENERIC_SPINLOCK
98 config RWSEM_XCHGADD_ALGORITHM
101 config ARCH_HAS_ILOG2_U32
104 config ARCH_HAS_ILOG2_U64
107 config ARCH_HAS_CPU_IDLE_WAIT
110 config GENERIC_CALIBRATE_DELAY
113 config GENERIC_TIME_VSYSCALL
117 config ARCH_HAS_CPU_RELAX
120 config ARCH_HAS_CACHE_LINE_SIZE
123 config HAVE_SETUP_PER_CPU_AREA
124 def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
126 config HAVE_CPUMASK_OF_CPU_MAP
129 config ARCH_HIBERNATION_POSSIBLE
131 depends on !SMP || !X86_VOYAGER
133 config ARCH_SUSPEND_POSSIBLE
135 depends on !X86_VOYAGER
141 config ARCH_POPULATES_NODE_MAP
148 config ARCH_SUPPORTS_AOUT
151 config ARCH_SUPPORTS_OPTIMIZED_INLINING
154 # Use the generic interrupt handling code in kernel/irq/:
155 config GENERIC_HARDIRQS
159 config GENERIC_IRQ_PROBE
163 config GENERIC_PENDING_IRQ
165 depends on GENERIC_HARDIRQS && SMP
170 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
175 depends on X86_32 && SMP
179 depends on X86_64 && SMP
184 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
187 config X86_BIOS_REBOOT
189 depends on !X86_VISWS && !X86_VOYAGER
192 config X86_TRAMPOLINE
194 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
199 source "init/Kconfig"
201 menu "Processor type and features"
203 source "kernel/time/Kconfig"
206 bool "Symmetric multi-processing support"
208 This enables support for systems with more than one CPU. If you have
209 a system with only one CPU, like most personal computers, say N. If
210 you have a system with more than one CPU, say Y.
212 If you say N here, the kernel will run on single and multiprocessor
213 machines, but will use only one CPU of a multiprocessor machine. If
214 you say Y here, the kernel will run on many, but not all,
215 singleprocessor machines. On a singleprocessor machine, the kernel
216 will run faster if you say N here.
218 Note that if you say Y here and choose architecture "586" or
219 "Pentium" under "Processor family", the kernel will not work on 486
220 architectures. Similarly, multiprocessor kernels for the "PPro"
221 architecture may not work on all Pentium based boards.
223 People using multiprocessor machines who say Y here should also say
224 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
225 Management" code will be disabled if you say Y here.
227 See also <file:Documentation/i386/IO-APIC.txt>,
228 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
229 <http://www.tldp.org/docs.html#howto>.
231 If you don't know what to do here, say N.
234 prompt "Subarchitecture Type"
240 Choose this option if your computer is a standard PC or compatible.
246 Select this for an AMD Elan processor.
248 Do not use this option for K6/Athlon/Opteron processors!
250 If unsure, choose "PC-compatible" instead.
254 depends on X86_32 && (SMP || BROKEN)
256 Voyager is an MCA-based 32-way capable SMP architecture proprietary
257 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
261 If you do not specifically know you have a Voyager based machine,
262 say N here, otherwise the kernel you build will not be bootable.
265 bool "NUMAQ (IBM/Sequent)"
266 depends on SMP && X86_32
269 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
270 multiquad box. This changes the way that processors are bootstrapped,
271 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
272 You will need a new lynxer.elf file to flash your firmware with - send
273 email to <Martin.Bligh@us.ibm.com>.
276 bool "Summit/EXA (IBM x440)"
277 depends on X86_32 && SMP
279 This option is needed for IBM systems that use the Summit/EXA chipset.
280 In particular, it is needed for the x440.
282 If you don't have one of these computers, you should say N here.
283 If you want to build a NUMA kernel, you must select ACPI.
286 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
287 depends on X86_32 && SMP
289 This option is needed for the systems that have more than 8 CPUs
290 and if the system is not of any sub-arch type above.
292 If you don't have such a system, you should say N here.
295 bool "SGI 320/540 (Visual Workstation)"
298 The SGI Visual Workstation series is an IA32-based workstation
299 based on SGI systems chips with some legacy PC hardware attached.
301 Say Y here to create a kernel to run on the SGI 320 or 540.
303 A kernel compiled for the Visual Workstation will not run on PCs
304 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
306 config X86_GENERICARCH
307 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
310 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
311 It is intended for a generic binary kernel.
312 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
315 bool "Support for Unisys ES7000 IA32 series"
316 depends on X86_32 && SMP
318 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
319 supposed to run on an IA32-based Unisys ES7000 system.
320 Only choose this option if you have such a system, otherwise you
324 bool "RDC R-321x SoC"
327 select X86_REBOOTFIXUPS
333 This option is needed for RDC R-321x system-on-chip, also known
335 If you don't have one of these chips, you should say N here.
338 bool "Support for ScaleMP vSMP"
342 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
343 supposed to run on these EM64T-based machines. Only choose this option
344 if you have one of these machines.
348 config SCHED_NO_NO_OMIT_FRAME_POINTER
350 prompt "Single-depth WCHAN output"
353 Calculate simpler /proc/<PID>/wchan values. If this option
354 is disabled then wchan values will recurse back to the
355 caller function. This provides more accurate wchan values,
356 at the expense of slightly more scheduling overhead.
358 If in doubt, say "Y".
360 menuconfig PARAVIRT_GUEST
361 bool "Paravirtualized guest support"
363 Say Y here to get to see options related to running Linux under
364 various hypervisors. This option alone does not add any kernel code.
366 If you say N, all options in this submenu will be skipped and disabled.
370 source "arch/x86/xen/Kconfig"
373 bool "VMI Guest support"
376 depends on !(X86_VISWS || X86_VOYAGER)
378 VMI provides a paravirtualized interface to the VMware ESX server
379 (it could be used by other hypervisors in theory too, but is not
380 at the moment), by linking the kernel to a GPL-ed ROM module
381 provided by the hypervisor.
384 bool "KVM paravirtualized clock"
386 select PARAVIRT_CLOCK
387 depends on !(X86_VISWS || X86_VOYAGER)
389 Turning on this option will allow you to run a paravirtualized clock
390 when running over the KVM hypervisor. Instead of relying on a PIT
391 (or probably other) emulation by the underlying device model, the host
392 provides the guest with timing infrastructure such as time of day, and
396 bool "KVM Guest support"
398 depends on !(X86_VISWS || X86_VOYAGER)
400 This option enables various optimizations for running under the KVM
403 source "arch/x86/lguest/Kconfig"
406 bool "Enable paravirtualization code"
407 depends on !(X86_VISWS || X86_VOYAGER)
409 This changes the kernel so it can modify itself when it is run
410 under a hypervisor, potentially improving performance significantly
411 over full virtualization. However, when run without a hypervisor
412 the kernel is theoretically slower and slightly larger.
414 config PARAVIRT_CLOCK
420 config MEMTEST_BOOTPARAM
421 bool "Memtest boot parameter"
425 This option adds a kernel parameter 'memtest', which allows memtest
426 to be disabled at boot. If this option is selected, memtest
427 functionality can be disabled with memtest=0 on the kernel
428 command line. The purpose of this option is to allow a single
429 kernel image to be distributed with memtest built in, but not
432 If you are unsure how to answer this question, answer Y.
434 config MEMTEST_BOOTPARAM_VALUE
435 int "Memtest boot parameter default value (0-4)"
436 depends on MEMTEST_BOOTPARAM
440 This option sets the default value for the kernel parameter
441 'memtest', which allows memtest to be disabled at boot. If this
442 option is set to 0 (zero), the memtest kernel parameter will
443 default to 0, disabling memtest at bootup. If this option is
444 set to 4, the memtest kernel parameter will default to 4,
445 enabling memtest at bootup, and use that as pattern number.
447 If you are unsure how to answer this question, answer 0.
451 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
454 config HAVE_ARCH_PARSE_SRAT
458 config X86_SUMMIT_NUMA
460 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
462 config X86_CYCLONE_TIMER
464 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
466 config ES7000_CLUSTERED_APIC
468 depends on SMP && X86_ES7000 && MPENTIUMIII
470 source "arch/x86/Kconfig.cpu"
474 prompt "HPET Timer Support" if X86_32
476 Use the IA-PC HPET (High Precision Event Timer) to manage
477 time in preference to the PIT and RTC, if a HPET is
479 HPET is the next generation timer replacing legacy 8254s.
480 The HPET provides a stable time base on SMP
481 systems, unlike the TSC, but it is more expensive to access,
482 as it is off-chip. You can find the HPET spec at
483 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
485 You can safely choose Y here. However, HPET will only be
486 activated if the platform and the BIOS support this feature.
487 Otherwise the 8254 will be used for timing services.
489 Choose N to continue using the legacy 8254 timer.
491 config HPET_EMULATE_RTC
493 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
495 # Mark as embedded because too many people got it wrong.
496 # The code disables itself when not needed.
499 bool "Enable DMI scanning" if EMBEDDED
501 Enabled scanning of DMI to identify machine quirks. Say Y
502 here unless you have verified that your setup is not
503 affected by entries in the DMI blacklist. Required by PNP
507 bool "GART IOMMU support" if EMBEDDED
511 depends on X86_64 && PCI
513 Support for full DMA access of devices with 32bit memory access only
514 on systems with more than 3GB. This is usually needed for USB,
515 sound, many IDE/SATA chipsets and some other devices.
516 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
517 based hardware IOMMU and a software bounce buffer based IOMMU used
518 on Intel systems and as fallback.
519 The code is only active when needed (enough memory and limited
520 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
524 bool "IBM Calgary IOMMU support"
526 depends on X86_64 && PCI && EXPERIMENTAL
528 Support for hardware IOMMUs in IBM's xSeries x366 and x460
529 systems. Needed to run systems with more than 3GB of memory
530 properly with 32-bit PCI devices that do not support DAC
531 (Double Address Cycle). Calgary also supports bus level
532 isolation, where all DMAs pass through the IOMMU. This
533 prevents them from going anywhere except their intended
534 destination. This catches hard-to-find kernel bugs and
535 mis-behaving drivers and devices that do not use the DMA-API
536 properly to set up their DMA buffers. The IOMMU can be
537 turned off at boot time with the iommu=off parameter.
538 Normally the kernel will make the right choice by itself.
541 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
543 prompt "Should Calgary be enabled by default?"
544 depends on CALGARY_IOMMU
546 Should Calgary be enabled by default? if you choose 'y', Calgary
547 will be used (if it exists). If you choose 'n', Calgary will not be
548 used even if it exists. If you choose 'n' and would like to use
549 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
553 bool "AMD IOMMU support"
555 depends on X86_64 && PCI && ACPI
557 Select this to get support for AMD IOMMU hardware in your system.
559 # need this always selected by IOMMU for the VIA workaround
563 Support for software bounce buffers used on x86-64 systems
564 which don't have a hardware IOMMU (e.g. the current generation
565 of Intel's x86-64 CPUs). Using this PCI devices which can only
566 access 32-bits of memory can be used on systems with more than
567 3 GB of memory. If unsure, say Y.
570 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
573 int "Maximum number of CPUs (2-255)"
576 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
579 This allows you to specify the maximum number of CPUs which this
580 kernel will support. The maximum supported value is 255 and the
581 minimum value which makes sense is 2.
583 This is purely to save memory - each supported CPU adds
584 approximately eight kilobytes to the kernel image.
587 bool "SMT (Hyperthreading) scheduler support"
590 SMT scheduler support improves the CPU scheduler's decision making
591 when dealing with Intel Pentium 4 chips with HyperThreading at a
592 cost of slightly increased overhead in some places. If unsure say
597 prompt "Multi-core scheduler support"
600 Multi-core scheduler support improves the CPU scheduler's decision
601 making when dealing with multi-core CPU chips at a cost of slightly
602 increased overhead in some places. If unsure say N here.
604 source "kernel/Kconfig.preempt"
607 bool "Local APIC support on uniprocessors"
608 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
610 A local APIC (Advanced Programmable Interrupt Controller) is an
611 integrated interrupt controller in the CPU. If you have a single-CPU
612 system which has a processor with a local APIC, you can say Y here to
613 enable and use it. If you say Y here even though your machine doesn't
614 have a local APIC, then the kernel will still run with no slowdown at
615 all. The local APIC supports CPU-generated self-interrupts (timer,
616 performance counters), and the NMI watchdog which detects hard
620 bool "IO-APIC support on uniprocessors"
621 depends on X86_UP_APIC
623 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
624 SMP-capable replacement for PC-style interrupt controllers. Most
625 SMP systems and many recent uniprocessor systems have one.
627 If you have a single-CPU system with an IO-APIC, you can say Y here
628 to use it. If you say Y here even though your machine doesn't have
629 an IO-APIC, then the kernel will still run with no slowdown at all.
631 config X86_LOCAL_APIC
633 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
637 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
639 config X86_VISWS_APIC
641 depends on X86_32 && X86_VISWS
644 bool "Machine Check Exception"
645 depends on !X86_VOYAGER
647 Machine Check Exception support allows the processor to notify the
648 kernel if it detects a problem (e.g. overheating, component failure).
649 The action the kernel takes depends on the severity of the problem,
650 ranging from a warning message on the console, to halting the machine.
651 Your processor must be a Pentium or newer to support this - check the
652 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
653 have a design flaw which leads to false MCE events - hence MCE is
654 disabled on all P5 processors, unless explicitly enabled with "mce"
655 as a boot argument. Similarly, if MCE is built in and creates a
656 problem on some new non-standard machine, you can boot with "nomce"
657 to disable it. MCE support simply ignores non-MCE processors like
658 the 386 and 486, so nearly everyone can say Y here.
662 prompt "Intel MCE features"
663 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
665 Additional support for intel specific MCE features such as
670 prompt "AMD MCE features"
671 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
673 Additional support for AMD specific MCE features such as
674 the DRAM Error Threshold.
676 config X86_MCE_NONFATAL
677 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
678 depends on X86_32 && X86_MCE
680 Enabling this feature starts a timer that triggers every 5 seconds which
681 will look at the machine check registers to see if anything happened.
682 Non-fatal problems automatically get corrected (but still logged).
683 Disable this if you don't want to see these messages.
684 Seeing the messages this option prints out may be indicative of dying
685 or out-of-spec (ie, overclocked) hardware.
686 This option only does something on certain CPUs.
687 (AMD Athlon/Duron and Intel Pentium 4)
689 config X86_MCE_P4THERMAL
690 bool "check for P4 thermal throttling interrupt."
691 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
693 Enabling this feature will cause a message to be printed when the P4
694 enters thermal throttling.
697 bool "Enable VM86 support" if EMBEDDED
701 This option is required by programs like DOSEMU to run 16-bit legacy
702 code on X86 processors. It also may be needed by software like
703 XFree86 to initialize some video cards via BIOS. Disabling this
704 option saves about 6k.
707 tristate "Toshiba Laptop support"
710 This adds a driver to safely access the System Management Mode of
711 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
712 not work on models with a Phoenix BIOS. The System Management Mode
713 is used to set the BIOS and power saving options on Toshiba portables.
715 For information on utilities to make use of this driver see the
716 Toshiba Linux utilities web site at:
717 <http://www.buzzard.org.uk/toshiba/>.
719 Say Y if you intend to run this kernel on a Toshiba portable.
723 tristate "Dell laptop support"
725 This adds a driver to safely access the System Management Mode
726 of the CPU on the Dell Inspiron 8000. The System Management Mode
727 is used to read cpu temperature and cooling fan status and to
728 control the fans on the I8K portables.
730 This driver has been tested only on the Inspiron 8000 but it may
731 also work with other Dell laptops. You can force loading on other
732 models by passing the parameter `force=1' to the module. Use at
735 For information on utilities to make use of this driver see the
736 I8K Linux utilities web site at:
737 <http://people.debian.org/~dz/i8k/>
739 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
742 config X86_REBOOTFIXUPS
744 prompt "Enable X86 board specific fixups for reboot"
745 depends on X86_32 && X86
747 This enables chipset and/or board specific fixups to be done
748 in order to get reboot to work correctly. This is only needed on
749 some combinations of hardware and BIOS. The symptom, for which
750 this config is intended, is when reboot ends with a stalled/hung
753 Currently, the only fixup is for the Geode machines using
754 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
756 Say Y if you want to enable the fixup. Currently, it's safe to
757 enable this option even if you don't need it.
761 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
764 If you say Y here, you will be able to update the microcode on
765 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
766 Pentium III, Pentium 4, Xeon etc. You will obviously need the
767 actual microcode binary data itself which is not shipped with the
770 For latest news and information on obtaining all the required
771 ingredients for this driver, check:
772 <http://www.urbanmyth.org/microcode/>.
774 To compile this driver as a module, choose M here: the
775 module will be called microcode.
777 config MICROCODE_OLD_INTERFACE
782 tristate "/dev/cpu/*/msr - Model-specific register support"
784 This device gives privileged processes access to the x86
785 Model-Specific Registers (MSRs). It is a character device with
786 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
787 MSR accesses are directed to a specific CPU on multi-processor
791 tristate "/dev/cpu/*/cpuid - CPU information support"
793 This device gives processes access to the x86 CPUID instruction to
794 be executed on a specific processor. It is a character device
795 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
799 prompt "High Memory Support"
800 default HIGHMEM4G if !X86_NUMAQ
801 default HIGHMEM64G if X86_NUMAQ
806 depends on !X86_NUMAQ
808 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
809 However, the address space of 32-bit x86 processors is only 4
810 Gigabytes large. That means that, if you have a large amount of
811 physical memory, not all of it can be "permanently mapped" by the
812 kernel. The physical memory that's not permanently mapped is called
815 If you are compiling a kernel which will never run on a machine with
816 more than 1 Gigabyte total physical RAM, answer "off" here (default
817 choice and suitable for most users). This will result in a "3GB/1GB"
818 split: 3GB are mapped so that each process sees a 3GB virtual memory
819 space and the remaining part of the 4GB virtual memory space is used
820 by the kernel to permanently map as much physical memory as
823 If the machine has between 1 and 4 Gigabytes physical RAM, then
826 If more than 4 Gigabytes is used then answer "64GB" here. This
827 selection turns Intel PAE (Physical Address Extension) mode on.
828 PAE implements 3-level paging on IA32 processors. PAE is fully
829 supported by Linux, PAE mode is implemented on all recent Intel
830 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
831 then the kernel will not boot on CPUs that don't support PAE!
833 The actual amount of total physical memory will either be
834 auto detected or can be forced by using a kernel command line option
835 such as "mem=256M". (Try "man bootparam" or see the documentation of
836 your boot loader (lilo or loadlin) about how to pass options to the
837 kernel at boot time.)
839 If unsure, say "off".
843 depends on !X86_NUMAQ
845 Select this if you have a 32-bit processor and between 1 and 4
846 gigabytes of physical RAM.
850 depends on !M386 && !M486
853 Select this if you have a 32-bit processor and more than 4
854 gigabytes of physical RAM.
859 depends on EXPERIMENTAL
860 prompt "Memory split" if EMBEDDED
864 Select the desired split between kernel and user memory.
866 If the address range available to the kernel is less than the
867 physical memory installed, the remaining memory will be available
868 as "high memory". Accessing high memory is a little more costly
869 than low memory, as it needs to be mapped into the kernel first.
870 Note that increasing the kernel address space limits the range
871 available to user programs, making the address space there
872 tighter. Selecting anything other than the default 3G/1G split
873 will also likely make your kernel incompatible with binary-only
876 If you are not absolutely sure what you are doing, leave this
880 bool "3G/1G user/kernel split"
881 config VMSPLIT_3G_OPT
883 bool "3G/1G user/kernel split (for full 1G low memory)"
885 bool "2G/2G user/kernel split"
886 config VMSPLIT_2G_OPT
888 bool "2G/2G user/kernel split (for full 2G low memory)"
890 bool "1G/3G user/kernel split"
895 default 0xB0000000 if VMSPLIT_3G_OPT
896 default 0x80000000 if VMSPLIT_2G
897 default 0x78000000 if VMSPLIT_2G_OPT
898 default 0x40000000 if VMSPLIT_1G
904 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
908 prompt "PAE (Physical Address Extension) Support"
909 depends on X86_32 && !HIGHMEM4G
910 select RESOURCES_64BIT
912 PAE is required for NX support, and furthermore enables
913 larger swapspace support for non-overcommit purposes. It
914 has the cost of more pagetable lookup overhead, and also
915 consumes more pagetable space per process.
917 # Common NUMA Features
919 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
921 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
923 default y if (X86_NUMAQ || X86_SUMMIT)
925 Enable NUMA (Non Uniform Memory Access) support.
926 The kernel will try to allocate memory used by a CPU on the
927 local memory controller of the CPU and add some more
928 NUMA awareness to the kernel.
930 For i386 this is currently highly experimental and should be only
931 used for kernel development. It might also cause boot failures.
932 For x86_64 this is recommended on all multiprocessor Opteron systems.
933 If the system is EM64T, you should say N unless your system is
936 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
937 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
941 prompt "Old style AMD Opteron NUMA detection"
942 depends on X86_64 && NUMA && PCI
944 Enable K8 NUMA node topology detection. You should say Y here if
945 you have a multi processor AMD K8 system. This uses an old
946 method to read the NUMA configuration directly from the builtin
947 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
948 instead, which also takes priority if both are compiled in.
950 config X86_64_ACPI_NUMA
952 prompt "ACPI NUMA detection"
953 depends on X86_64 && NUMA && ACPI && PCI
956 Enable ACPI SRAT based node topology detection.
958 # Some NUMA nodes have memory ranges that span
959 # other nodes. Even though a pfn is valid and
960 # between a node's start and end pfns, it may not
961 # reside on that node. See memmap_init_zone()
963 config NODES_SPAN_OTHER_NODES
965 depends on X86_64_ACPI_NUMA
968 bool "NUMA emulation"
969 depends on X86_64 && NUMA
971 Enable NUMA emulation. A flat machine will be split
972 into virtual nodes when booted with "numa=fake=N", where N is the
973 number of nodes. This is only useful for debugging.
976 int "Max num nodes shift(1-15)"
978 default "6" if X86_64
979 default "4" if X86_NUMAQ
981 depends on NEED_MULTIPLE_NODES
983 config HAVE_ARCH_BOOTMEM_NODE
985 depends on X86_32 && NUMA
987 config ARCH_HAVE_MEMORY_PRESENT
989 depends on X86_32 && DISCONTIGMEM
991 config NEED_NODE_MEMMAP_SIZE
993 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
995 config HAVE_ARCH_ALLOC_REMAP
997 depends on X86_32 && NUMA
999 config ARCH_FLATMEM_ENABLE
1001 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
1003 config ARCH_DISCONTIGMEM_ENABLE
1005 depends on NUMA && X86_32
1007 config ARCH_DISCONTIGMEM_DEFAULT
1009 depends on NUMA && X86_32
1011 config ARCH_SPARSEMEM_DEFAULT
1015 config ARCH_SPARSEMEM_ENABLE
1017 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1018 select SPARSEMEM_STATIC if X86_32
1019 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1021 config ARCH_SELECT_MEMORY_MODEL
1023 depends on ARCH_SPARSEMEM_ENABLE
1025 config ARCH_MEMORY_PROBE
1027 depends on MEMORY_HOTPLUG
1032 bool "Allocate 3rd-level pagetables from highmem"
1033 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1035 The VM uses one page table entry for each page of physical memory.
1036 For systems with a lot of RAM, this can be wasteful of precious
1037 low memory. Setting this option will put user-space page table
1038 entries in high memory.
1040 config MATH_EMULATION
1042 prompt "Math emulation" if X86_32
1044 Linux can emulate a math coprocessor (used for floating point
1045 operations) if you don't have one. 486DX and Pentium processors have
1046 a math coprocessor built in, 486SX and 386 do not, unless you added
1047 a 487DX or 387, respectively. (The messages during boot time can
1048 give you some hints here ["man dmesg"].) Everyone needs either a
1049 coprocessor or this emulation.
1051 If you don't have a math coprocessor, you need to say Y here; if you
1052 say Y here even though you have a coprocessor, the coprocessor will
1053 be used nevertheless. (This behavior can be changed with the kernel
1054 command line option "no387", which comes handy if your coprocessor
1055 is broken. Try "man bootparam" or see the documentation of your boot
1056 loader (lilo or loadlin) about how to pass options to the kernel at
1057 boot time.) This means that it is a good idea to say Y here if you
1058 intend to use this kernel on different machines.
1060 More information about the internals of the Linux math coprocessor
1061 emulation can be found in <file:arch/x86/math-emu/README>.
1063 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1064 kernel, it won't hurt.
1067 bool "MTRR (Memory Type Range Register) support"
1069 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1070 the Memory Type Range Registers (MTRRs) may be used to control
1071 processor access to memory ranges. This is most useful if you have
1072 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1073 allows bus write transfers to be combined into a larger transfer
1074 before bursting over the PCI/AGP bus. This can increase performance
1075 of image write operations 2.5 times or more. Saying Y here creates a
1076 /proc/mtrr file which may be used to manipulate your processor's
1077 MTRRs. Typically the X server should use this.
1079 This code has a reasonably generic interface so that similar
1080 control registers on other processors can be easily supported
1083 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1084 Registers (ARRs) which provide a similar functionality to MTRRs. For
1085 these, the ARRs are used to emulate the MTRRs.
1086 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1087 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1088 write-combining. All of these processors are supported by this code
1089 and it makes sense to say Y here if you have one of them.
1091 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1092 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1093 can lead to all sorts of problems, so it's good to say Y here.
1095 You can safely say Y even if your machine doesn't have MTRRs, you'll
1096 just add about 9 KB to your kernel.
1098 See <file:Documentation/mtrr.txt> for more information.
1102 prompt "x86 PAT support"
1105 Use PAT attributes to setup page level cache control.
1107 PATs are the modern equivalents of MTRRs and are much more
1108 flexible than MTRRs.
1110 Say N here if you see bootup problems (boot crash, boot hang,
1111 spontaneous reboots) or a non-working video driver.
1117 prompt "EFI runtime service support"
1120 This enables the kernel to use EFI runtime services that are
1121 available (such as the EFI variable services).
1123 This option is only useful on systems that have EFI firmware.
1124 In addition, you should use the latest ELILO loader available
1125 at <http://elilo.sourceforge.net> in order to take advantage
1126 of EFI runtime services. However, even with this option, the
1127 resultant kernel should continue to boot on existing non-EFI
1132 prompt "Enable kernel irq balancing"
1133 depends on X86_32 && SMP && X86_IO_APIC
1135 The default yes will allow the kernel to do irq load balancing.
1136 Saying no will keep the kernel from doing irq load balancing.
1140 prompt "Enable seccomp to safely compute untrusted bytecode"
1143 This kernel feature is useful for number crunching applications
1144 that may need to compute untrusted bytecode during their
1145 execution. By using pipes or other transports made available to
1146 the process as file descriptors supporting the read/write
1147 syscalls, it's possible to isolate those applications in
1148 their own address space using seccomp. Once seccomp is
1149 enabled via /proc/<pid>/seccomp, it cannot be disabled
1150 and the task is only allowed to execute a few safe syscalls
1151 defined by each seccomp mode.
1153 If unsure, say Y. Only embedded should say N here.
1155 config CC_STACKPROTECTOR
1156 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1157 depends on X86_64 && EXPERIMENTAL && BROKEN
1159 This option turns on the -fstack-protector GCC feature. This
1160 feature puts, at the beginning of critical functions, a canary
1161 value on the stack just before the return address, and validates
1162 the value just before actually returning. Stack based buffer
1163 overflows (that need to overwrite this return address) now also
1164 overwrite the canary, which gets detected and the attack is then
1165 neutralized via a kernel panic.
1167 This feature requires gcc version 4.2 or above, or a distribution
1168 gcc with the feature backported. Older versions are automatically
1169 detected and for those versions, this configuration option is ignored.
1171 config CC_STACKPROTECTOR_ALL
1172 bool "Use stack-protector for all functions"
1173 depends on CC_STACKPROTECTOR
1175 Normally, GCC only inserts the canary value protection for
1176 functions that use large-ish on-stack buffers. By enabling
1177 this option, GCC will be asked to do this for ALL functions.
1179 source kernel/Kconfig.hz
1182 bool "kexec system call"
1183 depends on X86_BIOS_REBOOT
1185 kexec is a system call that implements the ability to shutdown your
1186 current kernel, and to start another kernel. It is like a reboot
1187 but it is independent of the system firmware. And like a reboot
1188 you can start any kernel with it, not just Linux.
1190 The name comes from the similarity to the exec system call.
1192 It is an ongoing process to be certain the hardware in a machine
1193 is properly shutdown, so do not be surprised if this code does not
1194 initially work for you. It may help to enable device hotplugging
1195 support. As of this writing the exact hardware interface is
1196 strongly in flux, so no good recommendation can be made.
1199 bool "kernel crash dumps (EXPERIMENTAL)"
1200 depends on EXPERIMENTAL
1201 depends on X86_64 || (X86_32 && HIGHMEM)
1203 Generate crash dump after being started by kexec.
1204 This should be normally only set in special crash dump kernels
1205 which are loaded in the main kernel with kexec-tools into
1206 a specially reserved region and then later executed after
1207 a crash by kdump/kexec. The crash dump kernel must be compiled
1208 to a memory address not used by the main kernel or BIOS using
1209 PHYSICAL_START, or it must be built as a relocatable image
1210 (CONFIG_RELOCATABLE=y).
1211 For more details see Documentation/kdump/kdump.txt
1213 config PHYSICAL_START
1214 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1215 default "0x1000000" if X86_NUMAQ
1216 default "0x200000" if X86_64
1219 This gives the physical address where the kernel is loaded.
1221 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1222 bzImage will decompress itself to above physical address and
1223 run from there. Otherwise, bzImage will run from the address where
1224 it has been loaded by the boot loader and will ignore above physical
1227 In normal kdump cases one does not have to set/change this option
1228 as now bzImage can be compiled as a completely relocatable image
1229 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1230 address. This option is mainly useful for the folks who don't want
1231 to use a bzImage for capturing the crash dump and want to use a
1232 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1233 to be specifically compiled to run from a specific memory area
1234 (normally a reserved region) and this option comes handy.
1236 So if you are using bzImage for capturing the crash dump, leave
1237 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1238 Otherwise if you plan to use vmlinux for capturing the crash dump
1239 change this value to start of the reserved region (Typically 16MB
1240 0x1000000). In other words, it can be set based on the "X" value as
1241 specified in the "crashkernel=YM@XM" command line boot parameter
1242 passed to the panic-ed kernel. Typically this parameter is set as
1243 crashkernel=64M@16M. Please take a look at
1244 Documentation/kdump/kdump.txt for more details about crash dumps.
1246 Usage of bzImage for capturing the crash dump is recommended as
1247 one does not have to build two kernels. Same kernel can be used
1248 as production kernel and capture kernel. Above option should have
1249 gone away after relocatable bzImage support is introduced. But it
1250 is present because there are users out there who continue to use
1251 vmlinux for dump capture. This option should go away down the
1254 Don't change this unless you know what you are doing.
1257 bool "Build a relocatable kernel (EXPERIMENTAL)"
1258 depends on EXPERIMENTAL
1260 This builds a kernel image that retains relocation information
1261 so it can be loaded someplace besides the default 1MB.
1262 The relocations tend to make the kernel binary about 10% larger,
1263 but are discarded at runtime.
1265 One use is for the kexec on panic case where the recovery kernel
1266 must live at a different physical address than the primary
1269 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1270 it has been loaded at and the compile time physical address
1271 (CONFIG_PHYSICAL_START) is ignored.
1273 config PHYSICAL_ALIGN
1275 prompt "Alignment value to which kernel should be aligned" if X86_32
1276 default "0x100000" if X86_32
1277 default "0x200000" if X86_64
1278 range 0x2000 0x400000
1280 This value puts the alignment restrictions on physical address
1281 where kernel is loaded and run from. Kernel is compiled for an
1282 address which meets above alignment restriction.
1284 If bootloader loads the kernel at a non-aligned address and
1285 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1286 address aligned to above value and run from there.
1288 If bootloader loads the kernel at a non-aligned address and
1289 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1290 load address and decompress itself to the address it has been
1291 compiled for and run from there. The address for which kernel is
1292 compiled already meets above alignment restrictions. Hence the
1293 end result is that kernel runs from a physical address meeting
1294 above alignment restrictions.
1296 Don't change this unless you know what you are doing.
1299 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1300 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1302 Say Y here to experiment with turning CPUs off and on, and to
1303 enable suspend on SMP systems. CPUs can be controlled through
1304 /sys/devices/system/cpu.
1305 Say N if you want to disable CPU hotplug and don't need to
1310 prompt "Compat VDSO support"
1311 depends on X86_32 || IA32_EMULATION
1313 Map the 32-bit VDSO to the predictable old-style address too.
1315 Say N here if you are running a sufficiently recent glibc
1316 version (2.3.3 or later), to remove the high-mapped
1317 VDSO mapping and to exclusively use the randomized VDSO.
1323 config ARCH_ENABLE_MEMORY_HOTPLUG
1325 depends on X86_64 || (X86_32 && HIGHMEM)
1327 config HAVE_ARCH_EARLY_PFN_TO_NID
1331 menu "Power management options"
1332 depends on !X86_VOYAGER
1334 config ARCH_HIBERNATION_HEADER
1336 depends on X86_64 && HIBERNATION
1338 source "kernel/power/Kconfig"
1340 source "drivers/acpi/Kconfig"
1345 depends on APM || APM_MODULE
1348 tristate "APM (Advanced Power Management) BIOS support"
1349 depends on X86_32 && PM_SLEEP && !X86_VISWS
1351 APM is a BIOS specification for saving power using several different
1352 techniques. This is mostly useful for battery powered laptops with
1353 APM compliant BIOSes. If you say Y here, the system time will be
1354 reset after a RESUME operation, the /proc/apm device will provide
1355 battery status information, and user-space programs will receive
1356 notification of APM "events" (e.g. battery status change).
1358 If you select "Y" here, you can disable actual use of the APM
1359 BIOS by passing the "apm=off" option to the kernel at boot time.
1361 Note that the APM support is almost completely disabled for
1362 machines with more than one CPU.
1364 In order to use APM, you will need supporting software. For location
1365 and more information, read <file:Documentation/power/pm.txt> and the
1366 Battery Powered Linux mini-HOWTO, available from
1367 <http://www.tldp.org/docs.html#howto>.
1369 This driver does not spin down disk drives (see the hdparm(8)
1370 manpage ("man 8 hdparm") for that), and it doesn't turn off
1371 VESA-compliant "green" monitors.
1373 This driver does not support the TI 4000M TravelMate and the ACER
1374 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1375 desktop machines also don't have compliant BIOSes, and this driver
1376 may cause those machines to panic during the boot phase.
1378 Generally, if you don't have a battery in your machine, there isn't
1379 much point in using this driver and you should say N. If you get
1380 random kernel OOPSes or reboots that don't seem to be related to
1381 anything, try disabling/enabling this option (or disabling/enabling
1384 Some other things you should try when experiencing seemingly random,
1387 1) make sure that you have enough swap space and that it is
1389 2) pass the "no-hlt" option to the kernel
1390 3) switch on floating point emulation in the kernel and pass
1391 the "no387" option to the kernel
1392 4) pass the "floppy=nodma" option to the kernel
1393 5) pass the "mem=4M" option to the kernel (thereby disabling
1394 all but the first 4 MB of RAM)
1395 6) make sure that the CPU is not over clocked.
1396 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1397 8) disable the cache from your BIOS settings
1398 9) install a fan for the video card or exchange video RAM
1399 10) install a better fan for the CPU
1400 11) exchange RAM chips
1401 12) exchange the motherboard.
1403 To compile this driver as a module, choose M here: the
1404 module will be called apm.
1408 config APM_IGNORE_USER_SUSPEND
1409 bool "Ignore USER SUSPEND"
1411 This option will ignore USER SUSPEND requests. On machines with a
1412 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1413 series notebooks, it is necessary to say Y because of a BIOS bug.
1415 config APM_DO_ENABLE
1416 bool "Enable PM at boot time"
1418 Enable APM features at boot time. From page 36 of the APM BIOS
1419 specification: "When disabled, the APM BIOS does not automatically
1420 power manage devices, enter the Standby State, enter the Suspend
1421 State, or take power saving steps in response to CPU Idle calls."
1422 This driver will make CPU Idle calls when Linux is idle (unless this
1423 feature is turned off -- see "Do CPU IDLE calls", below). This
1424 should always save battery power, but more complicated APM features
1425 will be dependent on your BIOS implementation. You may need to turn
1426 this option off if your computer hangs at boot time when using APM
1427 support, or if it beeps continuously instead of suspending. Turn
1428 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1429 T400CDT. This is off by default since most machines do fine without
1433 bool "Make CPU Idle calls when idle"
1435 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1436 On some machines, this can activate improved power savings, such as
1437 a slowed CPU clock rate, when the machine is idle. These idle calls
1438 are made after the idle loop has run for some length of time (e.g.,
1439 333 mS). On some machines, this will cause a hang at boot time or
1440 whenever the CPU becomes idle. (On machines with more than one CPU,
1441 this option does nothing.)
1443 config APM_DISPLAY_BLANK
1444 bool "Enable console blanking using APM"
1446 Enable console blanking using the APM. Some laptops can use this to
1447 turn off the LCD backlight when the screen blanker of the Linux
1448 virtual console blanks the screen. Note that this is only used by
1449 the virtual console screen blanker, and won't turn off the backlight
1450 when using the X Window system. This also doesn't have anything to
1451 do with your VESA-compliant power-saving monitor. Further, this
1452 option doesn't work for all laptops -- it might not turn off your
1453 backlight at all, or it might print a lot of errors to the console,
1454 especially if you are using gpm.
1456 config APM_ALLOW_INTS
1457 bool "Allow interrupts during APM BIOS calls"
1459 Normally we disable external interrupts while we are making calls to
1460 the APM BIOS as a measure to lessen the effects of a badly behaving
1461 BIOS implementation. The BIOS should reenable interrupts if it
1462 needs to. Unfortunately, some BIOSes do not -- especially those in
1463 many of the newer IBM Thinkpads. If you experience hangs when you
1464 suspend, try setting this to Y. Otherwise, say N.
1466 config APM_REAL_MODE_POWER_OFF
1467 bool "Use real mode APM BIOS call to power off"
1469 Use real mode APM BIOS calls to switch off the computer. This is
1470 a work-around for a number of buggy BIOSes. Switch this option on if
1471 your computer crashes instead of powering off properly.
1475 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1477 source "drivers/cpuidle/Kconfig"
1482 menu "Bus options (PCI etc.)"
1485 bool "PCI support" if !X86_VISWS && !X86_VSMP
1486 depends on !X86_VOYAGER
1488 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1490 Find out whether you have a PCI motherboard. PCI is the name of a
1491 bus system, i.e. the way the CPU talks to the other stuff inside
1492 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1493 VESA. If you have PCI, say Y, otherwise N.
1496 prompt "PCI access mode"
1497 depends on X86_32 && PCI && !X86_VISWS
1500 On PCI systems, the BIOS can be used to detect the PCI devices and
1501 determine their configuration. However, some old PCI motherboards
1502 have BIOS bugs and may crash if this is done. Also, some embedded
1503 PCI-based systems don't have any BIOS at all. Linux can also try to
1504 detect the PCI hardware directly without using the BIOS.
1506 With this option, you can specify how Linux should detect the
1507 PCI devices. If you choose "BIOS", the BIOS will be used,
1508 if you choose "Direct", the BIOS won't be used, and if you
1509 choose "MMConfig", then PCI Express MMCONFIG will be used.
1510 If you choose "Any", the kernel will try MMCONFIG, then the
1511 direct access method and falls back to the BIOS if that doesn't
1512 work. If unsure, go with the default, which is "Any".
1517 config PCI_GOMMCONFIG
1534 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1536 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1539 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
1543 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1547 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1554 bool "Support mmconfig PCI config space access"
1555 depends on X86_64 && PCI && ACPI
1558 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1559 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1561 DMA remapping (DMAR) devices support enables independent address
1562 translations for Direct Memory Access (DMA) from devices.
1563 These DMA remapping devices are reported via ACPI tables
1564 and include PCI device scope covered by these DMA
1569 prompt "Support for Graphics workaround"
1572 Current Graphics drivers tend to use physical address
1573 for DMA and avoid using DMA APIs. Setting this config
1574 option permits the IOMMU driver to set a unity map for
1575 all the OS-visible memory. Hence the driver can continue
1576 to use physical addresses for DMA.
1578 config DMAR_FLOPPY_WA
1582 Floppy disk drivers are know to bypass DMA API calls
1583 thereby failing to work when IOMMU is enabled. This
1584 workaround will setup a 1:1 mapping for the first
1585 16M to make floppy (an ISA device) work.
1587 source "drivers/pci/pcie/Kconfig"
1589 source "drivers/pci/Kconfig"
1591 # x86_64 have no ISA slots, but do have ISA-style DMA.
1599 depends on !(X86_VOYAGER || X86_VISWS)
1601 Find out whether you have ISA slots on your motherboard. ISA is the
1602 name of a bus system, i.e. the way the CPU talks to the other stuff
1603 inside your box. Other bus systems are PCI, EISA, MicroChannel
1604 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1605 newer boards don't support it. If you have ISA, say Y, otherwise N.
1611 The Extended Industry Standard Architecture (EISA) bus was
1612 developed as an open alternative to the IBM MicroChannel bus.
1614 The EISA bus provided some of the features of the IBM MicroChannel
1615 bus while maintaining backward compatibility with cards made for
1616 the older ISA bus. The EISA bus saw limited use between 1988 and
1617 1995 when it was made obsolete by the PCI bus.
1619 Say Y here if you are building a kernel for an EISA-based machine.
1623 source "drivers/eisa/Kconfig"
1626 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1627 default y if X86_VOYAGER
1629 MicroChannel Architecture is found in some IBM PS/2 machines and
1630 laptops. It is a bus system similar to PCI or ISA. See
1631 <file:Documentation/mca.txt> (and especially the web page given
1632 there) before attempting to build an MCA bus kernel.
1634 source "drivers/mca/Kconfig"
1637 tristate "NatSemi SCx200 support"
1638 depends on !X86_VOYAGER
1640 This provides basic support for National Semiconductor's
1641 (now AMD's) Geode processors. The driver probes for the
1642 PCI-IDs of several on-chip devices, so its a good dependency
1643 for other scx200_* drivers.
1645 If compiled as a module, the driver is named scx200.
1647 config SCx200HR_TIMER
1648 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1649 depends on SCx200 && GENERIC_TIME
1652 This driver provides a clocksource built upon the on-chip
1653 27MHz high-resolution timer. Its also a workaround for
1654 NSC Geode SC-1100's buggy TSC, which loses time when the
1655 processor goes idle (as is done by the scheduler). The
1656 other workaround is idle=poll boot option.
1658 config GEODE_MFGPT_TIMER
1660 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1661 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1663 This driver provides a clock event source based on the MFGPT
1664 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1665 MFGPTs have a better resolution and max interval than the
1666 generic PIT, and are suitable for use as high-res timers.
1669 bool "One Laptop Per Child support"
1672 Add support for detecting the unique features of the OLPC
1679 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1681 source "drivers/pcmcia/Kconfig"
1683 source "drivers/pci/hotplug/Kconfig"
1688 menu "Executable file formats / Emulations"
1690 source "fs/Kconfig.binfmt"
1692 config IA32_EMULATION
1693 bool "IA32 Emulation"
1695 select COMPAT_BINFMT_ELF
1697 Include code to run 32-bit programs under a 64-bit kernel. You should
1698 likely turn this on, unless you're 100% sure that you don't have any
1699 32-bit programs left.
1702 tristate "IA32 a.out support"
1703 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1705 Support old a.out binaries in the 32bit emulation.
1709 depends on IA32_EMULATION
1711 config COMPAT_FOR_U64_ALIGNMENT
1715 config SYSVIPC_COMPAT
1717 depends on X86_64 && COMPAT && SYSVIPC
1722 source "net/Kconfig"
1724 source "drivers/Kconfig"
1726 source "drivers/firmware/Kconfig"
1730 source "arch/x86/Kconfig.debug"
1732 source "security/Kconfig"
1734 source "crypto/Kconfig"
1736 source "arch/x86/kvm/Kconfig"
1738 source "lib/Kconfig"