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_SMP || (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.
233 config X86_FIND_SMP_CONFIG
235 depends on X86_MPPARSE || X86_VOYAGER || X86_VISWS
240 bool "Enable MPS table"
241 depends on X86_LOCAL_APIC && !X86_VISWS
243 For old smp systems that do not have proper acpi support. Newer systems
244 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
250 depends on X86_LOCAL_APIC && !X86_VISWS
254 prompt "Subarchitecture Type"
260 Choose this option if your computer is a standard PC or compatible.
266 Select this for an AMD Elan processor.
268 Do not use this option for K6/Athlon/Opteron processors!
270 If unsure, choose "PC-compatible" instead.
274 depends on X86_32 && (SMP || BROKEN) && !PCI
276 Voyager is an MCA-based 32-way capable SMP architecture proprietary
277 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
281 If you do not specifically know you have a Voyager based machine,
282 say N here, otherwise the kernel you build will not be bootable.
285 bool "SGI 320/540 (Visual Workstation)"
286 depends on X86_32 && !PCI
288 The SGI Visual Workstation series is an IA32-based workstation
289 based on SGI systems chips with some legacy PC hardware attached.
291 Say Y here to create a kernel to run on the SGI 320 or 540.
293 A kernel compiled for the Visual Workstation will not run on PCs
294 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
296 config X86_GENERICARCH
297 bool "Generic architecture"
300 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
301 subarchitectures. It is intended for a generic binary kernel.
302 if you select them all, kernel will probe it one by one. and will
308 bool "NUMAQ (IBM/Sequent)"
309 depends on SMP && X86_32 && PCI && X86_MPPARSE
312 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
313 NUMA multiquad box. This changes the way that processors are
314 bootstrapped, and uses Clustered Logical APIC addressing mode instead
315 of Flat Logical. You will need a new lynxer.elf file to flash your
316 firmware with - send email to <Martin.Bligh@us.ibm.com>.
319 bool "Summit/EXA (IBM x440)"
320 depends on X86_32 && SMP
322 This option is needed for IBM systems that use the Summit/EXA chipset.
323 In particular, it is needed for the x440.
326 bool "Support for Unisys ES7000 IA32 series"
327 depends on X86_32 && SMP
329 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
330 supposed to run on an IA32-based Unisys ES7000 system.
333 bool "Support for big SMP systems with more than 8 CPUs"
334 depends on X86_32 && SMP
336 This option is needed for the systems that have more than 8 CPUs
337 and if the system is not of any sub-arch type above.
342 bool "RDC R-321x SoC"
345 select X86_REBOOTFIXUPS
351 This option is needed for RDC R-321x system-on-chip, also known
353 If you don't have one of these chips, you should say N here.
356 bool "Support for ScaleMP vSMP"
358 depends on X86_64 && !PCI
360 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
361 supposed to run on these EM64T-based machines. Only choose this option
362 if you have one of these machines.
366 config SCHED_NO_NO_OMIT_FRAME_POINTER
368 prompt "Single-depth WCHAN output"
371 Calculate simpler /proc/<PID>/wchan values. If this option
372 is disabled then wchan values will recurse back to the
373 caller function. This provides more accurate wchan values,
374 at the expense of slightly more scheduling overhead.
376 If in doubt, say "Y".
378 menuconfig PARAVIRT_GUEST
379 bool "Paravirtualized guest support"
381 Say Y here to get to see options related to running Linux under
382 various hypervisors. This option alone does not add any kernel code.
384 If you say N, all options in this submenu will be skipped and disabled.
388 source "arch/x86/xen/Kconfig"
391 bool "VMI Guest support"
394 depends on !(X86_VISWS || X86_VOYAGER)
396 VMI provides a paravirtualized interface to the VMware ESX server
397 (it could be used by other hypervisors in theory too, but is not
398 at the moment), by linking the kernel to a GPL-ed ROM module
399 provided by the hypervisor.
402 bool "KVM paravirtualized clock"
404 select PARAVIRT_CLOCK
405 depends on !(X86_VISWS || X86_VOYAGER)
407 Turning on this option will allow you to run a paravirtualized clock
408 when running over the KVM hypervisor. Instead of relying on a PIT
409 (or probably other) emulation by the underlying device model, the host
410 provides the guest with timing infrastructure such as time of day, and
414 bool "KVM Guest support"
416 depends on !(X86_VISWS || X86_VOYAGER)
418 This option enables various optimizations for running under the KVM
421 source "arch/x86/lguest/Kconfig"
424 bool "Enable paravirtualization code"
425 depends on !(X86_VISWS || X86_VOYAGER)
427 This changes the kernel so it can modify itself when it is run
428 under a hypervisor, potentially improving performance significantly
429 over full virtualization. However, when run without a hypervisor
430 the kernel is theoretically slower and slightly larger.
432 config PARAVIRT_CLOCK
438 config PARAVIRT_DEBUG
439 bool "paravirt-ops debugging"
440 depends on PARAVIRT && DEBUG_KERNEL
442 Enable to debug paravirt_ops internals. Specifically, BUG if
443 a paravirt_op is missing when it is called.
450 This option adds a kernel parameter 'memtest', which allows memtest
452 memtest=0, mean disabled; -- default
453 memtest=1, mean do 1 test pattern;
455 memtest=4, mean do 4 test patterns.
456 If you are unsure how to answer this question, answer Y.
460 depends on X86_32 && ACPI && NUMA && X86_GENERICARCH
463 config HAVE_ARCH_PARSE_SRAT
467 config X86_SUMMIT_NUMA
469 depends on X86_32 && NUMA && X86_GENERICARCH
471 config X86_CYCLONE_TIMER
473 depends on X86_GENERICARCH
475 config ES7000_CLUSTERED_APIC
477 depends on SMP && X86_ES7000 && MPENTIUMIII
479 source "arch/x86/Kconfig.cpu"
483 prompt "HPET Timer Support" if X86_32
485 Use the IA-PC HPET (High Precision Event Timer) to manage
486 time in preference to the PIT and RTC, if a HPET is
488 HPET is the next generation timer replacing legacy 8254s.
489 The HPET provides a stable time base on SMP
490 systems, unlike the TSC, but it is more expensive to access,
491 as it is off-chip. You can find the HPET spec at
492 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
494 You can safely choose Y here. However, HPET will only be
495 activated if the platform and the BIOS support this feature.
496 Otherwise the 8254 will be used for timing services.
498 Choose N to continue using the legacy 8254 timer.
500 config HPET_EMULATE_RTC
502 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
504 # Mark as embedded because too many people got it wrong.
505 # The code disables itself when not needed.
508 bool "Enable DMI scanning" if EMBEDDED
510 Enabled scanning of DMI to identify machine quirks. Say Y
511 here unless you have verified that your setup is not
512 affected by entries in the DMI blacklist. Required by PNP
516 bool "GART IOMMU support" if EMBEDDED
520 depends on X86_64 && PCI
522 Support for full DMA access of devices with 32bit memory access only
523 on systems with more than 3GB. This is usually needed for USB,
524 sound, many IDE/SATA chipsets and some other devices.
525 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
526 based hardware IOMMU and a software bounce buffer based IOMMU used
527 on Intel systems and as fallback.
528 The code is only active when needed (enough memory and limited
529 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
533 bool "IBM Calgary IOMMU support"
535 depends on X86_64 && PCI && EXPERIMENTAL
537 Support for hardware IOMMUs in IBM's xSeries x366 and x460
538 systems. Needed to run systems with more than 3GB of memory
539 properly with 32-bit PCI devices that do not support DAC
540 (Double Address Cycle). Calgary also supports bus level
541 isolation, where all DMAs pass through the IOMMU. This
542 prevents them from going anywhere except their intended
543 destination. This catches hard-to-find kernel bugs and
544 mis-behaving drivers and devices that do not use the DMA-API
545 properly to set up their DMA buffers. The IOMMU can be
546 turned off at boot time with the iommu=off parameter.
547 Normally the kernel will make the right choice by itself.
550 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
552 prompt "Should Calgary be enabled by default?"
553 depends on CALGARY_IOMMU
555 Should Calgary be enabled by default? if you choose 'y', Calgary
556 will be used (if it exists). If you choose 'n', Calgary will not be
557 used even if it exists. If you choose 'n' and would like to use
558 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
562 bool "AMD IOMMU support"
564 depends on X86_64 && PCI && ACPI
566 With this option you can enable support for AMD IOMMU hardware in
567 your system. An IOMMU is a hardware component which provides
568 remapping of DMA memory accesses from devices. With an AMD IOMMU you
569 can isolate the the DMA memory of different devices and protect the
570 system from misbehaving device drivers or hardware.
572 You can find out if your system has an AMD IOMMU if you look into
573 your BIOS for an option to enable it or if you have an IVRS ACPI
576 # need this always selected by IOMMU for the VIA workaround
580 Support for software bounce buffers used on x86-64 systems
581 which don't have a hardware IOMMU (e.g. the current generation
582 of Intel's x86-64 CPUs). Using this PCI devices which can only
583 access 32-bits of memory can be used on systems with more than
584 3 GB of memory. If unsure, say Y.
587 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
589 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
590 depends on X86_64 && SMP
593 Configure maximum number of CPUS and NUMA Nodes for this architecture.
604 int "Maximum number of CPUs (2-4096)"
607 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
610 This allows you to specify the maximum number of CPUs which this
611 kernel will support. The maximum supported value is 4096 and the
612 minimum value which makes sense is 2.
614 This is purely to save memory - each supported CPU adds
615 approximately eight kilobytes to the kernel image.
619 bool "SMT (Hyperthreading) scheduler support"
622 SMT scheduler support improves the CPU scheduler's decision making
623 when dealing with Intel Pentium 4 chips with HyperThreading at a
624 cost of slightly increased overhead in some places. If unsure say
629 prompt "Multi-core scheduler support"
632 Multi-core scheduler support improves the CPU scheduler's decision
633 making when dealing with multi-core CPU chips at a cost of slightly
634 increased overhead in some places. If unsure say N here.
636 source "kernel/Kconfig.preempt"
639 bool "Local APIC support on uniprocessors"
640 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
642 A local APIC (Advanced Programmable Interrupt Controller) is an
643 integrated interrupt controller in the CPU. If you have a single-CPU
644 system which has a processor with a local APIC, you can say Y here to
645 enable and use it. If you say Y here even though your machine doesn't
646 have a local APIC, then the kernel will still run with no slowdown at
647 all. The local APIC supports CPU-generated self-interrupts (timer,
648 performance counters), and the NMI watchdog which detects hard
652 bool "IO-APIC support on uniprocessors"
653 depends on X86_UP_APIC
655 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
656 SMP-capable replacement for PC-style interrupt controllers. Most
657 SMP systems and many recent uniprocessor systems have one.
659 If you have a single-CPU system with an IO-APIC, you can say Y here
660 to use it. If you say Y here even though your machine doesn't have
661 an IO-APIC, then the kernel will still run with no slowdown at all.
663 config X86_LOCAL_APIC
665 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
669 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
671 config X86_VISWS_APIC
673 depends on X86_32 && X86_VISWS
676 bool "Machine Check Exception"
677 depends on !X86_VOYAGER
679 Machine Check Exception support allows the processor to notify the
680 kernel if it detects a problem (e.g. overheating, component failure).
681 The action the kernel takes depends on the severity of the problem,
682 ranging from a warning message on the console, to halting the machine.
683 Your processor must be a Pentium or newer to support this - check the
684 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
685 have a design flaw which leads to false MCE events - hence MCE is
686 disabled on all P5 processors, unless explicitly enabled with "mce"
687 as a boot argument. Similarly, if MCE is built in and creates a
688 problem on some new non-standard machine, you can boot with "nomce"
689 to disable it. MCE support simply ignores non-MCE processors like
690 the 386 and 486, so nearly everyone can say Y here.
694 prompt "Intel MCE features"
695 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
697 Additional support for intel specific MCE features such as
702 prompt "AMD MCE features"
703 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
705 Additional support for AMD specific MCE features such as
706 the DRAM Error Threshold.
708 config X86_MCE_NONFATAL
709 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
710 depends on X86_32 && X86_MCE
712 Enabling this feature starts a timer that triggers every 5 seconds which
713 will look at the machine check registers to see if anything happened.
714 Non-fatal problems automatically get corrected (but still logged).
715 Disable this if you don't want to see these messages.
716 Seeing the messages this option prints out may be indicative of dying
717 or out-of-spec (ie, overclocked) hardware.
718 This option only does something on certain CPUs.
719 (AMD Athlon/Duron and Intel Pentium 4)
721 config X86_MCE_P4THERMAL
722 bool "check for P4 thermal throttling interrupt."
723 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
725 Enabling this feature will cause a message to be printed when the P4
726 enters thermal throttling.
729 bool "Enable VM86 support" if EMBEDDED
733 This option is required by programs like DOSEMU to run 16-bit legacy
734 code on X86 processors. It also may be needed by software like
735 XFree86 to initialize some video cards via BIOS. Disabling this
736 option saves about 6k.
739 tristate "Toshiba Laptop support"
742 This adds a driver to safely access the System Management Mode of
743 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
744 not work on models with a Phoenix BIOS. The System Management Mode
745 is used to set the BIOS and power saving options on Toshiba portables.
747 For information on utilities to make use of this driver see the
748 Toshiba Linux utilities web site at:
749 <http://www.buzzard.org.uk/toshiba/>.
751 Say Y if you intend to run this kernel on a Toshiba portable.
755 tristate "Dell laptop support"
757 This adds a driver to safely access the System Management Mode
758 of the CPU on the Dell Inspiron 8000. The System Management Mode
759 is used to read cpu temperature and cooling fan status and to
760 control the fans on the I8K portables.
762 This driver has been tested only on the Inspiron 8000 but it may
763 also work with other Dell laptops. You can force loading on other
764 models by passing the parameter `force=1' to the module. Use at
767 For information on utilities to make use of this driver see the
768 I8K Linux utilities web site at:
769 <http://people.debian.org/~dz/i8k/>
771 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
774 config X86_REBOOTFIXUPS
776 prompt "Enable X86 board specific fixups for reboot"
777 depends on X86_32 && X86
779 This enables chipset and/or board specific fixups to be done
780 in order to get reboot to work correctly. This is only needed on
781 some combinations of hardware and BIOS. The symptom, for which
782 this config is intended, is when reboot ends with a stalled/hung
785 Currently, the only fixup is for the Geode machines using
786 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
788 Say Y if you want to enable the fixup. Currently, it's safe to
789 enable this option even if you don't need it.
793 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
796 If you say Y here, you will be able to update the microcode on
797 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
798 Pentium III, Pentium 4, Xeon etc. You will obviously need the
799 actual microcode binary data itself which is not shipped with the
802 For latest news and information on obtaining all the required
803 ingredients for this driver, check:
804 <http://www.urbanmyth.org/microcode/>.
806 To compile this driver as a module, choose M here: the
807 module will be called microcode.
809 config MICROCODE_OLD_INTERFACE
814 tristate "/dev/cpu/*/msr - Model-specific register support"
816 This device gives privileged processes access to the x86
817 Model-Specific Registers (MSRs). It is a character device with
818 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
819 MSR accesses are directed to a specific CPU on multi-processor
823 tristate "/dev/cpu/*/cpuid - CPU information support"
825 This device gives processes access to the x86 CPUID instruction to
826 be executed on a specific processor. It is a character device
827 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
831 prompt "High Memory Support"
832 default HIGHMEM4G if !X86_NUMAQ
833 default HIGHMEM64G if X86_NUMAQ
838 depends on !X86_NUMAQ
840 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
841 However, the address space of 32-bit x86 processors is only 4
842 Gigabytes large. That means that, if you have a large amount of
843 physical memory, not all of it can be "permanently mapped" by the
844 kernel. The physical memory that's not permanently mapped is called
847 If you are compiling a kernel which will never run on a machine with
848 more than 1 Gigabyte total physical RAM, answer "off" here (default
849 choice and suitable for most users). This will result in a "3GB/1GB"
850 split: 3GB are mapped so that each process sees a 3GB virtual memory
851 space and the remaining part of the 4GB virtual memory space is used
852 by the kernel to permanently map as much physical memory as
855 If the machine has between 1 and 4 Gigabytes physical RAM, then
858 If more than 4 Gigabytes is used then answer "64GB" here. This
859 selection turns Intel PAE (Physical Address Extension) mode on.
860 PAE implements 3-level paging on IA32 processors. PAE is fully
861 supported by Linux, PAE mode is implemented on all recent Intel
862 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
863 then the kernel will not boot on CPUs that don't support PAE!
865 The actual amount of total physical memory will either be
866 auto detected or can be forced by using a kernel command line option
867 such as "mem=256M". (Try "man bootparam" or see the documentation of
868 your boot loader (lilo or loadlin) about how to pass options to the
869 kernel at boot time.)
871 If unsure, say "off".
875 depends on !X86_NUMAQ
877 Select this if you have a 32-bit processor and between 1 and 4
878 gigabytes of physical RAM.
882 depends on !M386 && !M486
885 Select this if you have a 32-bit processor and more than 4
886 gigabytes of physical RAM.
891 depends on EXPERIMENTAL
892 prompt "Memory split" if EMBEDDED
896 Select the desired split between kernel and user memory.
898 If the address range available to the kernel is less than the
899 physical memory installed, the remaining memory will be available
900 as "high memory". Accessing high memory is a little more costly
901 than low memory, as it needs to be mapped into the kernel first.
902 Note that increasing the kernel address space limits the range
903 available to user programs, making the address space there
904 tighter. Selecting anything other than the default 3G/1G split
905 will also likely make your kernel incompatible with binary-only
908 If you are not absolutely sure what you are doing, leave this
912 bool "3G/1G user/kernel split"
913 config VMSPLIT_3G_OPT
915 bool "3G/1G user/kernel split (for full 1G low memory)"
917 bool "2G/2G user/kernel split"
918 config VMSPLIT_2G_OPT
920 bool "2G/2G user/kernel split (for full 2G low memory)"
922 bool "1G/3G user/kernel split"
927 default 0xB0000000 if VMSPLIT_3G_OPT
928 default 0x80000000 if VMSPLIT_2G
929 default 0x78000000 if VMSPLIT_2G_OPT
930 default 0x40000000 if VMSPLIT_1G
936 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
940 prompt "PAE (Physical Address Extension) Support"
941 depends on X86_32 && !HIGHMEM4G
942 select RESOURCES_64BIT
944 PAE is required for NX support, and furthermore enables
945 larger swapspace support for non-overcommit purposes. It
946 has the cost of more pagetable lookup overhead, and also
947 consumes more pagetable space per process.
949 # Common NUMA Features
951 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
953 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
955 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
957 Enable NUMA (Non Uniform Memory Access) support.
958 The kernel will try to allocate memory used by a CPU on the
959 local memory controller of the CPU and add some more
960 NUMA awareness to the kernel.
962 For i386 this is currently highly experimental and should be only
963 used for kernel development. It might also cause boot failures.
964 For x86_64 this is recommended on all multiprocessor Opteron systems.
965 If the system is EM64T, you should say N unless your system is
968 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
969 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
973 prompt "Old style AMD Opteron NUMA detection"
974 depends on X86_64 && NUMA && PCI
976 Enable K8 NUMA node topology detection. You should say Y here if
977 you have a multi processor AMD K8 system. This uses an old
978 method to read the NUMA configuration directly from the builtin
979 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
980 instead, which also takes priority if both are compiled in.
982 config X86_64_ACPI_NUMA
984 prompt "ACPI NUMA detection"
985 depends on X86_64 && NUMA && ACPI && PCI
988 Enable ACPI SRAT based node topology detection.
990 # Some NUMA nodes have memory ranges that span
991 # other nodes. Even though a pfn is valid and
992 # between a node's start and end pfns, it may not
993 # reside on that node. See memmap_init_zone()
995 config NODES_SPAN_OTHER_NODES
997 depends on X86_64_ACPI_NUMA
1000 bool "NUMA emulation"
1001 depends on X86_64 && NUMA
1003 Enable NUMA emulation. A flat machine will be split
1004 into virtual nodes when booted with "numa=fake=N", where N is the
1005 number of nodes. This is only useful for debugging.
1016 int "Maximum NUMA Nodes (as a power of 2)"
1018 default "6" if X86_64
1019 default "4" if X86_NUMAQ
1021 depends on NEED_MULTIPLE_NODES
1023 Specify the maximum number of NUMA Nodes available on the target
1024 system. Increases memory reserved to accomodate various tables.
1027 config HAVE_ARCH_BOOTMEM_NODE
1029 depends on X86_32 && NUMA
1031 config ARCH_HAVE_MEMORY_PRESENT
1033 depends on X86_32 && DISCONTIGMEM
1035 config NEED_NODE_MEMMAP_SIZE
1037 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1039 config HAVE_ARCH_ALLOC_REMAP
1041 depends on X86_32 && NUMA
1043 config ARCH_FLATMEM_ENABLE
1045 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
1047 config ARCH_DISCONTIGMEM_ENABLE
1049 depends on NUMA && X86_32
1051 config ARCH_DISCONTIGMEM_DEFAULT
1053 depends on NUMA && X86_32
1055 config ARCH_SPARSEMEM_DEFAULT
1059 config ARCH_SPARSEMEM_ENABLE
1061 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1062 select SPARSEMEM_STATIC if X86_32
1063 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1065 config ARCH_SELECT_MEMORY_MODEL
1067 depends on ARCH_SPARSEMEM_ENABLE
1069 config ARCH_MEMORY_PROBE
1071 depends on MEMORY_HOTPLUG
1076 bool "Allocate 3rd-level pagetables from highmem"
1077 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1079 The VM uses one page table entry for each page of physical memory.
1080 For systems with a lot of RAM, this can be wasteful of precious
1081 low memory. Setting this option will put user-space page table
1082 entries in high memory.
1084 config MATH_EMULATION
1086 prompt "Math emulation" if X86_32
1088 Linux can emulate a math coprocessor (used for floating point
1089 operations) if you don't have one. 486DX and Pentium processors have
1090 a math coprocessor built in, 486SX and 386 do not, unless you added
1091 a 487DX or 387, respectively. (The messages during boot time can
1092 give you some hints here ["man dmesg"].) Everyone needs either a
1093 coprocessor or this emulation.
1095 If you don't have a math coprocessor, you need to say Y here; if you
1096 say Y here even though you have a coprocessor, the coprocessor will
1097 be used nevertheless. (This behavior can be changed with the kernel
1098 command line option "no387", which comes handy if your coprocessor
1099 is broken. Try "man bootparam" or see the documentation of your boot
1100 loader (lilo or loadlin) about how to pass options to the kernel at
1101 boot time.) This means that it is a good idea to say Y here if you
1102 intend to use this kernel on different machines.
1104 More information about the internals of the Linux math coprocessor
1105 emulation can be found in <file:arch/x86/math-emu/README>.
1107 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1108 kernel, it won't hurt.
1111 bool "MTRR (Memory Type Range Register) support"
1113 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1114 the Memory Type Range Registers (MTRRs) may be used to control
1115 processor access to memory ranges. This is most useful if you have
1116 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1117 allows bus write transfers to be combined into a larger transfer
1118 before bursting over the PCI/AGP bus. This can increase performance
1119 of image write operations 2.5 times or more. Saying Y here creates a
1120 /proc/mtrr file which may be used to manipulate your processor's
1121 MTRRs. Typically the X server should use this.
1123 This code has a reasonably generic interface so that similar
1124 control registers on other processors can be easily supported
1127 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1128 Registers (ARRs) which provide a similar functionality to MTRRs. For
1129 these, the ARRs are used to emulate the MTRRs.
1130 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1131 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1132 write-combining. All of these processors are supported by this code
1133 and it makes sense to say Y here if you have one of them.
1135 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1136 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1137 can lead to all sorts of problems, so it's good to say Y here.
1139 You can safely say Y even if your machine doesn't have MTRRs, you'll
1140 just add about 9 KB to your kernel.
1142 See <file:Documentation/mtrr.txt> for more information.
1144 config MTRR_SANITIZER
1146 prompt "MTRR cleanup support"
1149 Convert MTRR layout from continuous to discrete, so some X driver
1150 could add WB entries.
1152 Say N here if you see bootup problems (boot crash, boot hang,
1153 spontaneous reboots).
1155 Could be disabled with disable_mtrr_cleanup. Also mtrr_chunk_size
1156 could be used to send largest mtrr entry size for continuous block
1157 to hold holes (aka. UC entries)
1161 config MTRR_SANITIZER_ENABLE_DEFAULT
1162 int "MTRR cleanup enable value (0-1)"
1165 depends on MTRR_SANITIZER
1167 Enable mtrr cleanup default value
1169 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1170 int "MTRR cleanup spare reg num (0-7)"
1173 depends on MTRR_SANITIZER
1175 mtrr cleanup spare entries default, it can be changed via
1180 prompt "x86 PAT support"
1183 Use PAT attributes to setup page level cache control.
1185 PATs are the modern equivalents of MTRRs and are much more
1186 flexible than MTRRs.
1188 Say N here if you see bootup problems (boot crash, boot hang,
1189 spontaneous reboots) or a non-working video driver.
1195 prompt "EFI runtime service support"
1198 This enables the kernel to use EFI runtime services that are
1199 available (such as the EFI variable services).
1201 This option is only useful on systems that have EFI firmware.
1202 In addition, you should use the latest ELILO loader available
1203 at <http://elilo.sourceforge.net> in order to take advantage
1204 of EFI runtime services. However, even with this option, the
1205 resultant kernel should continue to boot on existing non-EFI
1210 prompt "Enable kernel irq balancing"
1211 depends on X86_32 && SMP && X86_IO_APIC
1213 The default yes will allow the kernel to do irq load balancing.
1214 Saying no will keep the kernel from doing irq load balancing.
1218 prompt "Enable seccomp to safely compute untrusted bytecode"
1221 This kernel feature is useful for number crunching applications
1222 that may need to compute untrusted bytecode during their
1223 execution. By using pipes or other transports made available to
1224 the process as file descriptors supporting the read/write
1225 syscalls, it's possible to isolate those applications in
1226 their own address space using seccomp. Once seccomp is
1227 enabled via /proc/<pid>/seccomp, it cannot be disabled
1228 and the task is only allowed to execute a few safe syscalls
1229 defined by each seccomp mode.
1231 If unsure, say Y. Only embedded should say N here.
1233 config CC_STACKPROTECTOR
1234 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1235 depends on X86_64 && EXPERIMENTAL && BROKEN
1237 This option turns on the -fstack-protector GCC feature. This
1238 feature puts, at the beginning of critical functions, a canary
1239 value on the stack just before the return address, and validates
1240 the value just before actually returning. Stack based buffer
1241 overflows (that need to overwrite this return address) now also
1242 overwrite the canary, which gets detected and the attack is then
1243 neutralized via a kernel panic.
1245 This feature requires gcc version 4.2 or above, or a distribution
1246 gcc with the feature backported. Older versions are automatically
1247 detected and for those versions, this configuration option is ignored.
1249 config CC_STACKPROTECTOR_ALL
1250 bool "Use stack-protector for all functions"
1251 depends on CC_STACKPROTECTOR
1253 Normally, GCC only inserts the canary value protection for
1254 functions that use large-ish on-stack buffers. By enabling
1255 this option, GCC will be asked to do this for ALL functions.
1257 source kernel/Kconfig.hz
1260 bool "kexec system call"
1261 depends on X86_BIOS_REBOOT
1263 kexec is a system call that implements the ability to shutdown your
1264 current kernel, and to start another kernel. It is like a reboot
1265 but it is independent of the system firmware. And like a reboot
1266 you can start any kernel with it, not just Linux.
1268 The name comes from the similarity to the exec system call.
1270 It is an ongoing process to be certain the hardware in a machine
1271 is properly shutdown, so do not be surprised if this code does not
1272 initially work for you. It may help to enable device hotplugging
1273 support. As of this writing the exact hardware interface is
1274 strongly in flux, so no good recommendation can be made.
1277 bool "kernel crash dumps (EXPERIMENTAL)"
1278 depends on X86_64 || (X86_32 && HIGHMEM)
1280 Generate crash dump after being started by kexec.
1281 This should be normally only set in special crash dump kernels
1282 which are loaded in the main kernel with kexec-tools into
1283 a specially reserved region and then later executed after
1284 a crash by kdump/kexec. The crash dump kernel must be compiled
1285 to a memory address not used by the main kernel or BIOS using
1286 PHYSICAL_START, or it must be built as a relocatable image
1287 (CONFIG_RELOCATABLE=y).
1288 For more details see Documentation/kdump/kdump.txt
1290 config PHYSICAL_START
1291 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1292 default "0x1000000" if X86_NUMAQ
1293 default "0x200000" if X86_64
1296 This gives the physical address where the kernel is loaded.
1298 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1299 bzImage will decompress itself to above physical address and
1300 run from there. Otherwise, bzImage will run from the address where
1301 it has been loaded by the boot loader and will ignore above physical
1304 In normal kdump cases one does not have to set/change this option
1305 as now bzImage can be compiled as a completely relocatable image
1306 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1307 address. This option is mainly useful for the folks who don't want
1308 to use a bzImage for capturing the crash dump and want to use a
1309 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1310 to be specifically compiled to run from a specific memory area
1311 (normally a reserved region) and this option comes handy.
1313 So if you are using bzImage for capturing the crash dump, leave
1314 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1315 Otherwise if you plan to use vmlinux for capturing the crash dump
1316 change this value to start of the reserved region (Typically 16MB
1317 0x1000000). In other words, it can be set based on the "X" value as
1318 specified in the "crashkernel=YM@XM" command line boot parameter
1319 passed to the panic-ed kernel. Typically this parameter is set as
1320 crashkernel=64M@16M. Please take a look at
1321 Documentation/kdump/kdump.txt for more details about crash dumps.
1323 Usage of bzImage for capturing the crash dump is recommended as
1324 one does not have to build two kernels. Same kernel can be used
1325 as production kernel and capture kernel. Above option should have
1326 gone away after relocatable bzImage support is introduced. But it
1327 is present because there are users out there who continue to use
1328 vmlinux for dump capture. This option should go away down the
1331 Don't change this unless you know what you are doing.
1334 bool "Build a relocatable kernel (EXPERIMENTAL)"
1335 depends on EXPERIMENTAL
1337 This builds a kernel image that retains relocation information
1338 so it can be loaded someplace besides the default 1MB.
1339 The relocations tend to make the kernel binary about 10% larger,
1340 but are discarded at runtime.
1342 One use is for the kexec on panic case where the recovery kernel
1343 must live at a different physical address than the primary
1346 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1347 it has been loaded at and the compile time physical address
1348 (CONFIG_PHYSICAL_START) is ignored.
1350 config PHYSICAL_ALIGN
1352 prompt "Alignment value to which kernel should be aligned" if X86_32
1353 default "0x100000" if X86_32
1354 default "0x200000" if X86_64
1355 range 0x2000 0x400000
1357 This value puts the alignment restrictions on physical address
1358 where kernel is loaded and run from. Kernel is compiled for an
1359 address which meets above alignment restriction.
1361 If bootloader loads the kernel at a non-aligned address and
1362 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1363 address aligned to above value and run from there.
1365 If bootloader loads the kernel at a non-aligned address and
1366 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1367 load address and decompress itself to the address it has been
1368 compiled for and run from there. The address for which kernel is
1369 compiled already meets above alignment restrictions. Hence the
1370 end result is that kernel runs from a physical address meeting
1371 above alignment restrictions.
1373 Don't change this unless you know what you are doing.
1376 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1377 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1379 Say Y here to experiment with turning CPUs off and on, and to
1380 enable suspend on SMP systems. CPUs can be controlled through
1381 /sys/devices/system/cpu.
1382 Say N if you want to disable CPU hotplug and don't need to
1387 prompt "Compat VDSO support"
1388 depends on X86_32 || IA32_EMULATION
1390 Map the 32-bit VDSO to the predictable old-style address too.
1392 Say N here if you are running a sufficiently recent glibc
1393 version (2.3.3 or later), to remove the high-mapped
1394 VDSO mapping and to exclusively use the randomized VDSO.
1400 config ARCH_ENABLE_MEMORY_HOTPLUG
1402 depends on X86_64 || (X86_32 && HIGHMEM)
1404 config HAVE_ARCH_EARLY_PFN_TO_NID
1408 menu "Power management options"
1409 depends on !X86_VOYAGER
1411 config ARCH_HIBERNATION_HEADER
1413 depends on X86_64 && HIBERNATION
1415 source "kernel/power/Kconfig"
1417 source "drivers/acpi/Kconfig"
1422 depends on APM || APM_MODULE
1425 tristate "APM (Advanced Power Management) BIOS support"
1426 depends on X86_32 && PM_SLEEP && !X86_VISWS
1428 APM is a BIOS specification for saving power using several different
1429 techniques. This is mostly useful for battery powered laptops with
1430 APM compliant BIOSes. If you say Y here, the system time will be
1431 reset after a RESUME operation, the /proc/apm device will provide
1432 battery status information, and user-space programs will receive
1433 notification of APM "events" (e.g. battery status change).
1435 If you select "Y" here, you can disable actual use of the APM
1436 BIOS by passing the "apm=off" option to the kernel at boot time.
1438 Note that the APM support is almost completely disabled for
1439 machines with more than one CPU.
1441 In order to use APM, you will need supporting software. For location
1442 and more information, read <file:Documentation/power/pm.txt> and the
1443 Battery Powered Linux mini-HOWTO, available from
1444 <http://www.tldp.org/docs.html#howto>.
1446 This driver does not spin down disk drives (see the hdparm(8)
1447 manpage ("man 8 hdparm") for that), and it doesn't turn off
1448 VESA-compliant "green" monitors.
1450 This driver does not support the TI 4000M TravelMate and the ACER
1451 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1452 desktop machines also don't have compliant BIOSes, and this driver
1453 may cause those machines to panic during the boot phase.
1455 Generally, if you don't have a battery in your machine, there isn't
1456 much point in using this driver and you should say N. If you get
1457 random kernel OOPSes or reboots that don't seem to be related to
1458 anything, try disabling/enabling this option (or disabling/enabling
1461 Some other things you should try when experiencing seemingly random,
1464 1) make sure that you have enough swap space and that it is
1466 2) pass the "no-hlt" option to the kernel
1467 3) switch on floating point emulation in the kernel and pass
1468 the "no387" option to the kernel
1469 4) pass the "floppy=nodma" option to the kernel
1470 5) pass the "mem=4M" option to the kernel (thereby disabling
1471 all but the first 4 MB of RAM)
1472 6) make sure that the CPU is not over clocked.
1473 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1474 8) disable the cache from your BIOS settings
1475 9) install a fan for the video card or exchange video RAM
1476 10) install a better fan for the CPU
1477 11) exchange RAM chips
1478 12) exchange the motherboard.
1480 To compile this driver as a module, choose M here: the
1481 module will be called apm.
1485 config APM_IGNORE_USER_SUSPEND
1486 bool "Ignore USER SUSPEND"
1488 This option will ignore USER SUSPEND requests. On machines with a
1489 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1490 series notebooks, it is necessary to say Y because of a BIOS bug.
1492 config APM_DO_ENABLE
1493 bool "Enable PM at boot time"
1495 Enable APM features at boot time. From page 36 of the APM BIOS
1496 specification: "When disabled, the APM BIOS does not automatically
1497 power manage devices, enter the Standby State, enter the Suspend
1498 State, or take power saving steps in response to CPU Idle calls."
1499 This driver will make CPU Idle calls when Linux is idle (unless this
1500 feature is turned off -- see "Do CPU IDLE calls", below). This
1501 should always save battery power, but more complicated APM features
1502 will be dependent on your BIOS implementation. You may need to turn
1503 this option off if your computer hangs at boot time when using APM
1504 support, or if it beeps continuously instead of suspending. Turn
1505 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1506 T400CDT. This is off by default since most machines do fine without
1510 bool "Make CPU Idle calls when idle"
1512 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1513 On some machines, this can activate improved power savings, such as
1514 a slowed CPU clock rate, when the machine is idle. These idle calls
1515 are made after the idle loop has run for some length of time (e.g.,
1516 333 mS). On some machines, this will cause a hang at boot time or
1517 whenever the CPU becomes idle. (On machines with more than one CPU,
1518 this option does nothing.)
1520 config APM_DISPLAY_BLANK
1521 bool "Enable console blanking using APM"
1523 Enable console blanking using the APM. Some laptops can use this to
1524 turn off the LCD backlight when the screen blanker of the Linux
1525 virtual console blanks the screen. Note that this is only used by
1526 the virtual console screen blanker, and won't turn off the backlight
1527 when using the X Window system. This also doesn't have anything to
1528 do with your VESA-compliant power-saving monitor. Further, this
1529 option doesn't work for all laptops -- it might not turn off your
1530 backlight at all, or it might print a lot of errors to the console,
1531 especially if you are using gpm.
1533 config APM_ALLOW_INTS
1534 bool "Allow interrupts during APM BIOS calls"
1536 Normally we disable external interrupts while we are making calls to
1537 the APM BIOS as a measure to lessen the effects of a badly behaving
1538 BIOS implementation. The BIOS should reenable interrupts if it
1539 needs to. Unfortunately, some BIOSes do not -- especially those in
1540 many of the newer IBM Thinkpads. If you experience hangs when you
1541 suspend, try setting this to Y. Otherwise, say N.
1543 config APM_REAL_MODE_POWER_OFF
1544 bool "Use real mode APM BIOS call to power off"
1546 Use real mode APM BIOS calls to switch off the computer. This is
1547 a work-around for a number of buggy BIOSes. Switch this option on if
1548 your computer crashes instead of powering off properly.
1552 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1554 source "drivers/cpuidle/Kconfig"
1559 menu "Bus options (PCI etc.)"
1564 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1566 Find out whether you have a PCI motherboard. PCI is the name of a
1567 bus system, i.e. the way the CPU talks to the other stuff inside
1568 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1569 VESA. If you have PCI, say Y, otherwise N.
1572 prompt "PCI access mode"
1573 depends on X86_32 && PCI && !X86_VISWS
1576 On PCI systems, the BIOS can be used to detect the PCI devices and
1577 determine their configuration. However, some old PCI motherboards
1578 have BIOS bugs and may crash if this is done. Also, some embedded
1579 PCI-based systems don't have any BIOS at all. Linux can also try to
1580 detect the PCI hardware directly without using the BIOS.
1582 With this option, you can specify how Linux should detect the
1583 PCI devices. If you choose "BIOS", the BIOS will be used,
1584 if you choose "Direct", the BIOS won't be used, and if you
1585 choose "MMConfig", then PCI Express MMCONFIG will be used.
1586 If you choose "Any", the kernel will try MMCONFIG, then the
1587 direct access method and falls back to the BIOS if that doesn't
1588 work. If unsure, go with the default, which is "Any".
1593 config PCI_GOMMCONFIG
1610 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1612 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1615 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
1619 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1623 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1630 bool "Support mmconfig PCI config space access"
1631 depends on X86_64 && PCI && ACPI
1634 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1635 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1637 DMA remapping (DMAR) devices support enables independent address
1638 translations for Direct Memory Access (DMA) from devices.
1639 These DMA remapping devices are reported via ACPI tables
1640 and include PCI device scope covered by these DMA
1645 prompt "Support for Graphics workaround"
1648 Current Graphics drivers tend to use physical address
1649 for DMA and avoid using DMA APIs. Setting this config
1650 option permits the IOMMU driver to set a unity map for
1651 all the OS-visible memory. Hence the driver can continue
1652 to use physical addresses for DMA.
1654 config DMAR_FLOPPY_WA
1658 Floppy disk drivers are know to bypass DMA API calls
1659 thereby failing to work when IOMMU is enabled. This
1660 workaround will setup a 1:1 mapping for the first
1661 16M to make floppy (an ISA device) work.
1663 source "drivers/pci/pcie/Kconfig"
1665 source "drivers/pci/Kconfig"
1667 # x86_64 have no ISA slots, but do have ISA-style DMA.
1675 depends on !(X86_VOYAGER || X86_VISWS)
1677 Find out whether you have ISA slots on your motherboard. ISA is the
1678 name of a bus system, i.e. the way the CPU talks to the other stuff
1679 inside your box. Other bus systems are PCI, EISA, MicroChannel
1680 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1681 newer boards don't support it. If you have ISA, say Y, otherwise N.
1687 The Extended Industry Standard Architecture (EISA) bus was
1688 developed as an open alternative to the IBM MicroChannel bus.
1690 The EISA bus provided some of the features of the IBM MicroChannel
1691 bus while maintaining backward compatibility with cards made for
1692 the older ISA bus. The EISA bus saw limited use between 1988 and
1693 1995 when it was made obsolete by the PCI bus.
1695 Say Y here if you are building a kernel for an EISA-based machine.
1699 source "drivers/eisa/Kconfig"
1702 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1703 default y if X86_VOYAGER
1705 MicroChannel Architecture is found in some IBM PS/2 machines and
1706 laptops. It is a bus system similar to PCI or ISA. See
1707 <file:Documentation/mca.txt> (and especially the web page given
1708 there) before attempting to build an MCA bus kernel.
1710 source "drivers/mca/Kconfig"
1713 tristate "NatSemi SCx200 support"
1714 depends on !X86_VOYAGER
1716 This provides basic support for National Semiconductor's
1717 (now AMD's) Geode processors. The driver probes for the
1718 PCI-IDs of several on-chip devices, so its a good dependency
1719 for other scx200_* drivers.
1721 If compiled as a module, the driver is named scx200.
1723 config SCx200HR_TIMER
1724 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1725 depends on SCx200 && GENERIC_TIME
1728 This driver provides a clocksource built upon the on-chip
1729 27MHz high-resolution timer. Its also a workaround for
1730 NSC Geode SC-1100's buggy TSC, which loses time when the
1731 processor goes idle (as is done by the scheduler). The
1732 other workaround is idle=poll boot option.
1734 config GEODE_MFGPT_TIMER
1736 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1737 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1739 This driver provides a clock event source based on the MFGPT
1740 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1741 MFGPTs have a better resolution and max interval than the
1742 generic PIT, and are suitable for use as high-res timers.
1745 bool "One Laptop Per Child support"
1748 Add support for detecting the unique features of the OLPC
1755 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1757 source "drivers/pcmcia/Kconfig"
1759 source "drivers/pci/hotplug/Kconfig"
1764 menu "Executable file formats / Emulations"
1766 source "fs/Kconfig.binfmt"
1768 config IA32_EMULATION
1769 bool "IA32 Emulation"
1771 select COMPAT_BINFMT_ELF
1773 Include code to run 32-bit programs under a 64-bit kernel. You should
1774 likely turn this on, unless you're 100% sure that you don't have any
1775 32-bit programs left.
1778 tristate "IA32 a.out support"
1779 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1781 Support old a.out binaries in the 32bit emulation.
1785 depends on IA32_EMULATION
1787 config COMPAT_FOR_U64_ALIGNMENT
1791 config SYSVIPC_COMPAT
1793 depends on X86_64 && COMPAT && SYSVIPC
1798 source "net/Kconfig"
1800 source "drivers/Kconfig"
1802 source "drivers/firmware/Kconfig"
1806 source "arch/x86/Kconfig.debug"
1808 source "security/Kconfig"
1810 source "crypto/Kconfig"
1812 source "arch/x86/kvm/Kconfig"
1814 source "lib/Kconfig"
projects / linux-2.6 / blob