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
24 select HAVE_IOREMAP_PROT
26 select ARCH_WANT_OPTIONAL_GPIOLIB
27 select HAVE_KRETPROBES
28 select HAVE_DYNAMIC_FTRACE
30 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
31 select HAVE_ARCH_KGDB if !X86_VOYAGER
32 select HAVE_GENERIC_DMA_COHERENT if X86_32
33 select HAVE_EFFICIENT_UNALIGNED_ACCESS
37 default "arch/x86/configs/i386_defconfig" if X86_32
38 default "arch/x86/configs/x86_64_defconfig" if X86_64
41 config GENERIC_LOCKBREAK
47 config GENERIC_CMOS_UPDATE
50 config CLOCKSOURCE_WATCHDOG
53 config GENERIC_CLOCKEVENTS
56 config GENERIC_CLOCKEVENTS_BROADCAST
58 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
60 config LOCKDEP_SUPPORT
63 config STACKTRACE_SUPPORT
66 config HAVE_LATENCYTOP_SUPPORT
69 config FAST_CMPXCHG_LOCAL
82 config GENERIC_ISA_DMA
92 config GENERIC_HWEIGHT
98 config ARCH_MAY_HAVE_PC_FDC
101 config RWSEM_GENERIC_SPINLOCK
104 config RWSEM_XCHGADD_ALGORITHM
107 config ARCH_HAS_ILOG2_U32
110 config ARCH_HAS_ILOG2_U64
113 config ARCH_HAS_CPU_IDLE_WAIT
116 config GENERIC_CALIBRATE_DELAY
119 config GENERIC_TIME_VSYSCALL
123 config ARCH_HAS_CPU_RELAX
126 config ARCH_HAS_CACHE_LINE_SIZE
129 config HAVE_SETUP_PER_CPU_AREA
130 def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER)
132 config HAVE_CPUMASK_OF_CPU_MAP
135 config ARCH_HIBERNATION_POSSIBLE
137 depends on !SMP || !X86_VOYAGER
139 config ARCH_SUSPEND_POSSIBLE
141 depends on !X86_VOYAGER
147 config ARCH_POPULATES_NODE_MAP
154 config ARCH_SUPPORTS_AOUT
157 config ARCH_SUPPORTS_OPTIMIZED_INLINING
160 # Use the generic interrupt handling code in kernel/irq/:
161 config GENERIC_HARDIRQS
165 config GENERIC_IRQ_PROBE
169 config GENERIC_PENDING_IRQ
171 depends on GENERIC_HARDIRQS && SMP
176 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
177 select USE_GENERIC_SMP_HELPERS
182 depends on X86_32 && SMP
186 depends on X86_64 && SMP
191 depends on (X86_32 && !X86_VOYAGER) || X86_64
194 config X86_BIOS_REBOOT
196 depends on !X86_VOYAGER
199 config X86_TRAMPOLINE
201 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
206 source "init/Kconfig"
208 menu "Processor type and features"
210 source "kernel/time/Kconfig"
213 bool "Symmetric multi-processing support"
215 This enables support for systems with more than one CPU. If you have
216 a system with only one CPU, like most personal computers, say N. If
217 you have a system with more than one CPU, say Y.
219 If you say N here, the kernel will run on single and multiprocessor
220 machines, but will use only one CPU of a multiprocessor machine. If
221 you say Y here, the kernel will run on many, but not all,
222 singleprocessor machines. On a singleprocessor machine, the kernel
223 will run faster if you say N here.
225 Note that if you say Y here and choose architecture "586" or
226 "Pentium" under "Processor family", the kernel will not work on 486
227 architectures. Similarly, multiprocessor kernels for the "PPro"
228 architecture may not work on all Pentium based boards.
230 People using multiprocessor machines who say Y here should also say
231 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
232 Management" code will be disabled if you say Y here.
234 See also <file:Documentation/i386/IO-APIC.txt>,
235 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
236 <http://www.tldp.org/docs.html#howto>.
238 If you don't know what to do here, say N.
240 config X86_FIND_SMP_CONFIG
242 depends on X86_MPPARSE || X86_VOYAGER
247 bool "Enable MPS table"
248 depends on X86_LOCAL_APIC
250 For old smp systems that do not have proper acpi support. Newer systems
251 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
257 depends on X86_LOCAL_APIC
261 prompt "Subarchitecture Type"
267 Choose this option if your computer is a standard PC or compatible.
273 Select this for an AMD Elan processor.
275 Do not use this option for K6/Athlon/Opteron processors!
277 If unsure, choose "PC-compatible" instead.
281 depends on X86_32 && (SMP || BROKEN) && !PCI
283 Voyager is an MCA-based 32-way capable SMP architecture proprietary
284 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
288 If you do not specifically know you have a Voyager based machine,
289 say N here, otherwise the kernel you build will not be bootable.
291 config X86_GENERICARCH
292 bool "Generic architecture"
295 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
296 subarchitectures. It is intended for a generic binary kernel.
297 if you select them all, kernel will probe it one by one. and will
303 bool "NUMAQ (IBM/Sequent)"
304 depends on SMP && X86_32 && PCI && X86_MPPARSE
307 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
308 NUMA multiquad box. This changes the way that processors are
309 bootstrapped, and uses Clustered Logical APIC addressing mode instead
310 of Flat Logical. You will need a new lynxer.elf file to flash your
311 firmware with - send email to <Martin.Bligh@us.ibm.com>.
314 bool "Summit/EXA (IBM x440)"
315 depends on X86_32 && SMP
317 This option is needed for IBM systems that use the Summit/EXA chipset.
318 In particular, it is needed for the x440.
321 bool "Support for Unisys ES7000 IA32 series"
322 depends on X86_32 && SMP
324 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
325 supposed to run on an IA32-based Unisys ES7000 system.
328 bool "Support for big SMP systems with more than 8 CPUs"
329 depends on X86_32 && SMP
331 This option is needed for the systems that have more than 8 CPUs
332 and if the system is not of any sub-arch type above.
337 bool "Support for ScaleMP vSMP"
339 depends on X86_64 && PCI
341 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
342 supposed to run on these EM64T-based machines. Only choose this option
343 if you have one of these machines.
348 bool "SGI 320/540 (Visual Workstation)"
349 depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT
351 The SGI Visual Workstation series is an IA32-based workstation
352 based on SGI systems chips with some legacy PC hardware attached.
354 Say Y here to create a kernel to run on the SGI 320 or 540.
356 A kernel compiled for the Visual Workstation will run on general
357 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
360 bool "RDC R-321x SoC"
363 select X86_REBOOTFIXUPS
365 This option is needed for RDC R-321x system-on-chip, also known
367 If you don't have one of these chips, you should say N here.
369 config SCHED_NO_NO_OMIT_FRAME_POINTER
371 prompt "Single-depth WCHAN output"
374 Calculate simpler /proc/<PID>/wchan values. If this option
375 is disabled then wchan values will recurse back to the
376 caller function. This provides more accurate wchan values,
377 at the expense of slightly more scheduling overhead.
379 If in doubt, say "Y".
381 menuconfig PARAVIRT_GUEST
382 bool "Paravirtualized guest support"
384 Say Y here to get to see options related to running Linux under
385 various hypervisors. This option alone does not add any kernel code.
387 If you say N, all options in this submenu will be skipped and disabled.
391 source "arch/x86/xen/Kconfig"
394 bool "VMI Guest support"
397 depends on !X86_VOYAGER
399 VMI provides a paravirtualized interface to the VMware ESX server
400 (it could be used by other hypervisors in theory too, but is not
401 at the moment), by linking the kernel to a GPL-ed ROM module
402 provided by the hypervisor.
405 bool "KVM paravirtualized clock"
407 select PARAVIRT_CLOCK
408 depends on !X86_VOYAGER
410 Turning on this option will allow you to run a paravirtualized clock
411 when running over the KVM hypervisor. Instead of relying on a PIT
412 (or probably other) emulation by the underlying device model, the host
413 provides the guest with timing infrastructure such as time of day, and
417 bool "KVM Guest support"
419 depends on !X86_VOYAGER
421 This option enables various optimizations for running under the KVM
424 source "arch/x86/lguest/Kconfig"
427 bool "Enable paravirtualization code"
428 depends on !X86_VOYAGER
430 This changes the kernel so it can modify itself when it is run
431 under a hypervisor, potentially improving performance significantly
432 over full virtualization. However, when run without a hypervisor
433 the kernel is theoretically slower and slightly larger.
435 config PARAVIRT_CLOCK
441 config PARAVIRT_DEBUG
442 bool "paravirt-ops debugging"
443 depends on PARAVIRT && DEBUG_KERNEL
445 Enable to debug paravirt_ops internals. Specifically, BUG if
446 a paravirt_op is missing when it is called.
451 This option adds a kernel parameter 'memtest', which allows memtest
453 memtest=0, mean disabled; -- default
454 memtest=1, mean do 1 test pattern;
456 memtest=4, mean do 4 test patterns.
457 If you are unsure how to answer this question, answer N.
459 config X86_SUMMIT_NUMA
461 depends on X86_32 && NUMA && X86_GENERICARCH
463 config X86_CYCLONE_TIMER
465 depends on X86_GENERICARCH
467 config ES7000_CLUSTERED_APIC
469 depends on SMP && X86_ES7000 && MPENTIUMIII
471 source "arch/x86/Kconfig.cpu"
475 prompt "HPET Timer Support" if X86_32
477 Use the IA-PC HPET (High Precision Event Timer) to manage
478 time in preference to the PIT and RTC, if a HPET is
480 HPET is the next generation timer replacing legacy 8254s.
481 The HPET provides a stable time base on SMP
482 systems, unlike the TSC, but it is more expensive to access,
483 as it is off-chip. You can find the HPET spec at
484 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
486 You can safely choose Y here. However, HPET will only be
487 activated if the platform and the BIOS support this feature.
488 Otherwise the 8254 will be used for timing services.
490 Choose N to continue using the legacy 8254 timer.
492 config HPET_EMULATE_RTC
494 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
496 # Mark as embedded because too many people got it wrong.
497 # The code disables itself when not needed.
500 bool "Enable DMI scanning" if EMBEDDED
502 Enabled scanning of DMI to identify machine quirks. Say Y
503 here unless you have verified that your setup is not
504 affected by entries in the DMI blacklist. Required by PNP
508 bool "GART IOMMU support" if EMBEDDED
512 depends on X86_64 && PCI
514 Support for full DMA access of devices with 32bit memory access only
515 on systems with more than 3GB. This is usually needed for USB,
516 sound, many IDE/SATA chipsets and some other devices.
517 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
518 based hardware IOMMU and a software bounce buffer based IOMMU used
519 on Intel systems and as fallback.
520 The code is only active when needed (enough memory and limited
521 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
525 bool "IBM Calgary IOMMU support"
527 depends on X86_64 && PCI && EXPERIMENTAL
529 Support for hardware IOMMUs in IBM's xSeries x366 and x460
530 systems. Needed to run systems with more than 3GB of memory
531 properly with 32-bit PCI devices that do not support DAC
532 (Double Address Cycle). Calgary also supports bus level
533 isolation, where all DMAs pass through the IOMMU. This
534 prevents them from going anywhere except their intended
535 destination. This catches hard-to-find kernel bugs and
536 mis-behaving drivers and devices that do not use the DMA-API
537 properly to set up their DMA buffers. The IOMMU can be
538 turned off at boot time with the iommu=off parameter.
539 Normally the kernel will make the right choice by itself.
542 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
544 prompt "Should Calgary be enabled by default?"
545 depends on CALGARY_IOMMU
547 Should Calgary be enabled by default? if you choose 'y', Calgary
548 will be used (if it exists). If you choose 'n', Calgary will not be
549 used even if it exists. If you choose 'n' and would like to use
550 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
554 bool "AMD IOMMU support"
556 depends on X86_64 && PCI && ACPI
558 With this option you can enable support for AMD IOMMU hardware in
559 your system. An IOMMU is a hardware component which provides
560 remapping of DMA memory accesses from devices. With an AMD IOMMU you
561 can isolate the the DMA memory of different devices and protect the
562 system from misbehaving device drivers or hardware.
564 You can find out if your system has an AMD IOMMU if you look into
565 your BIOS for an option to enable it or if you have an IVRS ACPI
568 # need this always selected by IOMMU for the VIA workaround
572 Support for software bounce buffers used on x86-64 systems
573 which don't have a hardware IOMMU (e.g. the current generation
574 of Intel's x86-64 CPUs). Using this PCI devices which can only
575 access 32-bits of memory can be used on systems with more than
576 3 GB of memory. If unsure, say Y.
579 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
582 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
583 depends on X86_64 && SMP && BROKEN
586 Configure maximum number of CPUS and NUMA Nodes for this architecture.
590 int "Maximum number of CPUs (2-512)" if !MAXSMP
593 default "4096" if MAXSMP
594 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
597 This allows you to specify the maximum number of CPUs which this
598 kernel will support. The maximum supported value is 512 and the
599 minimum value which makes sense is 2.
601 This is purely to save memory - each supported CPU adds
602 approximately eight kilobytes to the kernel image.
605 bool "SMT (Hyperthreading) scheduler support"
608 SMT scheduler support improves the CPU scheduler's decision making
609 when dealing with Intel Pentium 4 chips with HyperThreading at a
610 cost of slightly increased overhead in some places. If unsure say
615 prompt "Multi-core scheduler support"
618 Multi-core scheduler support improves the CPU scheduler's decision
619 making when dealing with multi-core CPU chips at a cost of slightly
620 increased overhead in some places. If unsure say N here.
622 source "kernel/Kconfig.preempt"
625 bool "Local APIC support on uniprocessors"
626 depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH)
628 A local APIC (Advanced Programmable Interrupt Controller) is an
629 integrated interrupt controller in the CPU. If you have a single-CPU
630 system which has a processor with a local APIC, you can say Y here to
631 enable and use it. If you say Y here even though your machine doesn't
632 have a local APIC, then the kernel will still run with no slowdown at
633 all. The local APIC supports CPU-generated self-interrupts (timer,
634 performance counters), and the NMI watchdog which detects hard
638 bool "IO-APIC support on uniprocessors"
639 depends on X86_UP_APIC
641 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
642 SMP-capable replacement for PC-style interrupt controllers. Most
643 SMP systems and many recent uniprocessor systems have one.
645 If you have a single-CPU system with an IO-APIC, you can say Y here
646 to use it. If you say Y here even though your machine doesn't have
647 an IO-APIC, then the kernel will still run with no slowdown at all.
649 config X86_LOCAL_APIC
651 depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
655 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
657 config X86_VISWS_APIC
659 depends on X86_32 && X86_VISWS
662 bool "Machine Check Exception"
663 depends on !X86_VOYAGER
665 Machine Check Exception support allows the processor to notify the
666 kernel if it detects a problem (e.g. overheating, component failure).
667 The action the kernel takes depends on the severity of the problem,
668 ranging from a warning message on the console, to halting the machine.
669 Your processor must be a Pentium or newer to support this - check the
670 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
671 have a design flaw which leads to false MCE events - hence MCE is
672 disabled on all P5 processors, unless explicitly enabled with "mce"
673 as a boot argument. Similarly, if MCE is built in and creates a
674 problem on some new non-standard machine, you can boot with "nomce"
675 to disable it. MCE support simply ignores non-MCE processors like
676 the 386 and 486, so nearly everyone can say Y here.
680 prompt "Intel MCE features"
681 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
683 Additional support for intel specific MCE features such as
688 prompt "AMD MCE features"
689 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
691 Additional support for AMD specific MCE features such as
692 the DRAM Error Threshold.
694 config X86_MCE_NONFATAL
695 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
696 depends on X86_32 && X86_MCE
698 Enabling this feature starts a timer that triggers every 5 seconds which
699 will look at the machine check registers to see if anything happened.
700 Non-fatal problems automatically get corrected (but still logged).
701 Disable this if you don't want to see these messages.
702 Seeing the messages this option prints out may be indicative of dying
703 or out-of-spec (ie, overclocked) hardware.
704 This option only does something on certain CPUs.
705 (AMD Athlon/Duron and Intel Pentium 4)
707 config X86_MCE_P4THERMAL
708 bool "check for P4 thermal throttling interrupt."
709 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
711 Enabling this feature will cause a message to be printed when the P4
712 enters thermal throttling.
715 bool "Enable VM86 support" if EMBEDDED
719 This option is required by programs like DOSEMU to run 16-bit legacy
720 code on X86 processors. It also may be needed by software like
721 XFree86 to initialize some video cards via BIOS. Disabling this
722 option saves about 6k.
725 tristate "Toshiba Laptop support"
728 This adds a driver to safely access the System Management Mode of
729 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
730 not work on models with a Phoenix BIOS. The System Management Mode
731 is used to set the BIOS and power saving options on Toshiba portables.
733 For information on utilities to make use of this driver see the
734 Toshiba Linux utilities web site at:
735 <http://www.buzzard.org.uk/toshiba/>.
737 Say Y if you intend to run this kernel on a Toshiba portable.
741 tristate "Dell laptop support"
743 This adds a driver to safely access the System Management Mode
744 of the CPU on the Dell Inspiron 8000. The System Management Mode
745 is used to read cpu temperature and cooling fan status and to
746 control the fans on the I8K portables.
748 This driver has been tested only on the Inspiron 8000 but it may
749 also work with other Dell laptops. You can force loading on other
750 models by passing the parameter `force=1' to the module. Use at
753 For information on utilities to make use of this driver see the
754 I8K Linux utilities web site at:
755 <http://people.debian.org/~dz/i8k/>
757 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
760 config X86_REBOOTFIXUPS
762 prompt "Enable X86 board specific fixups for reboot"
763 depends on X86_32 && X86
765 This enables chipset and/or board specific fixups to be done
766 in order to get reboot to work correctly. This is only needed on
767 some combinations of hardware and BIOS. The symptom, for which
768 this config is intended, is when reboot ends with a stalled/hung
771 Currently, the only fixup is for the Geode machines using
772 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
774 Say Y if you want to enable the fixup. Currently, it's safe to
775 enable this option even if you don't need it.
779 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
782 If you say Y here, you will be able to update the microcode on
783 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
784 Pentium III, Pentium 4, Xeon etc. You will obviously need the
785 actual microcode binary data itself which is not shipped with the
788 For latest news and information on obtaining all the required
789 ingredients for this driver, check:
790 <http://www.urbanmyth.org/microcode/>.
792 To compile this driver as a module, choose M here: the
793 module will be called microcode.
795 config MICROCODE_OLD_INTERFACE
800 tristate "/dev/cpu/*/msr - Model-specific register support"
802 This device gives privileged processes access to the x86
803 Model-Specific Registers (MSRs). It is a character device with
804 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
805 MSR accesses are directed to a specific CPU on multi-processor
809 tristate "/dev/cpu/*/cpuid - CPU information support"
811 This device gives processes access to the x86 CPUID instruction to
812 be executed on a specific processor. It is a character device
813 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
817 prompt "High Memory Support"
818 default HIGHMEM4G if !X86_NUMAQ
819 default HIGHMEM64G if X86_NUMAQ
824 depends on !X86_NUMAQ
826 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
827 However, the address space of 32-bit x86 processors is only 4
828 Gigabytes large. That means that, if you have a large amount of
829 physical memory, not all of it can be "permanently mapped" by the
830 kernel. The physical memory that's not permanently mapped is called
833 If you are compiling a kernel which will never run on a machine with
834 more than 1 Gigabyte total physical RAM, answer "off" here (default
835 choice and suitable for most users). This will result in a "3GB/1GB"
836 split: 3GB are mapped so that each process sees a 3GB virtual memory
837 space and the remaining part of the 4GB virtual memory space is used
838 by the kernel to permanently map as much physical memory as
841 If the machine has between 1 and 4 Gigabytes physical RAM, then
844 If more than 4 Gigabytes is used then answer "64GB" here. This
845 selection turns Intel PAE (Physical Address Extension) mode on.
846 PAE implements 3-level paging on IA32 processors. PAE is fully
847 supported by Linux, PAE mode is implemented on all recent Intel
848 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
849 then the kernel will not boot on CPUs that don't support PAE!
851 The actual amount of total physical memory will either be
852 auto detected or can be forced by using a kernel command line option
853 such as "mem=256M". (Try "man bootparam" or see the documentation of
854 your boot loader (lilo or loadlin) about how to pass options to the
855 kernel at boot time.)
857 If unsure, say "off".
861 depends on !X86_NUMAQ
863 Select this if you have a 32-bit processor and between 1 and 4
864 gigabytes of physical RAM.
868 depends on !M386 && !M486
871 Select this if you have a 32-bit processor and more than 4
872 gigabytes of physical RAM.
877 depends on EXPERIMENTAL
878 prompt "Memory split" if EMBEDDED
882 Select the desired split between kernel and user memory.
884 If the address range available to the kernel is less than the
885 physical memory installed, the remaining memory will be available
886 as "high memory". Accessing high memory is a little more costly
887 than low memory, as it needs to be mapped into the kernel first.
888 Note that increasing the kernel address space limits the range
889 available to user programs, making the address space there
890 tighter. Selecting anything other than the default 3G/1G split
891 will also likely make your kernel incompatible with binary-only
894 If you are not absolutely sure what you are doing, leave this
898 bool "3G/1G user/kernel split"
899 config VMSPLIT_3G_OPT
901 bool "3G/1G user/kernel split (for full 1G low memory)"
903 bool "2G/2G user/kernel split"
904 config VMSPLIT_2G_OPT
906 bool "2G/2G user/kernel split (for full 2G low memory)"
908 bool "1G/3G user/kernel split"
913 default 0xB0000000 if VMSPLIT_3G_OPT
914 default 0x80000000 if VMSPLIT_2G
915 default 0x78000000 if VMSPLIT_2G_OPT
916 default 0x40000000 if VMSPLIT_1G
922 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
926 prompt "PAE (Physical Address Extension) Support"
927 depends on X86_32 && !HIGHMEM4G
928 select RESOURCES_64BIT
930 PAE is required for NX support, and furthermore enables
931 larger swapspace support for non-overcommit purposes. It
932 has the cost of more pagetable lookup overhead, and also
933 consumes more pagetable space per process.
935 # Common NUMA Features
937 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
939 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
941 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
943 Enable NUMA (Non Uniform Memory Access) support.
944 The kernel will try to allocate memory used by a CPU on the
945 local memory controller of the CPU and add some more
946 NUMA awareness to the kernel.
948 For 32-bit this is currently highly experimental and should be only
949 used for kernel development. It might also cause boot failures.
950 For 64-bit this is recommended on all multiprocessor Opteron systems.
951 If the system is EM64T, you should say N unless your system is
954 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
955 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
959 prompt "Old style AMD Opteron NUMA detection"
960 depends on X86_64 && NUMA && PCI
962 Enable K8 NUMA node topology detection. You should say Y here if
963 you have a multi processor AMD K8 system. This uses an old
964 method to read the NUMA configuration directly from the builtin
965 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
966 instead, which also takes priority if both are compiled in.
968 config X86_64_ACPI_NUMA
970 prompt "ACPI NUMA detection"
971 depends on X86_64 && NUMA && ACPI && PCI
974 Enable ACPI SRAT based node topology detection.
976 # Some NUMA nodes have memory ranges that span
977 # other nodes. Even though a pfn is valid and
978 # between a node's start and end pfns, it may not
979 # reside on that node. See memmap_init_zone()
981 config NODES_SPAN_OTHER_NODES
983 depends on X86_64_ACPI_NUMA
986 bool "NUMA emulation"
987 depends on X86_64 && NUMA
989 Enable NUMA emulation. A flat machine will be split
990 into virtual nodes when booted with "numa=fake=N", where N is the
991 number of nodes. This is only useful for debugging.
994 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
996 default "9" if MAXSMP
997 default "6" if X86_64
998 default "4" if X86_NUMAQ
1000 depends on NEED_MULTIPLE_NODES
1002 Specify the maximum number of NUMA Nodes available on the target
1003 system. Increases memory reserved to accomodate various tables.
1005 config HAVE_ARCH_BOOTMEM_NODE
1007 depends on X86_32 && NUMA
1009 config ARCH_HAVE_MEMORY_PRESENT
1011 depends on X86_32 && DISCONTIGMEM
1013 config NEED_NODE_MEMMAP_SIZE
1015 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1017 config HAVE_ARCH_ALLOC_REMAP
1019 depends on X86_32 && NUMA
1021 config ARCH_FLATMEM_ENABLE
1023 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
1025 config ARCH_DISCONTIGMEM_ENABLE
1027 depends on NUMA && X86_32
1029 config ARCH_DISCONTIGMEM_DEFAULT
1031 depends on NUMA && X86_32
1033 config ARCH_SPARSEMEM_DEFAULT
1037 config ARCH_SPARSEMEM_ENABLE
1039 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1040 select SPARSEMEM_STATIC if X86_32
1041 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1043 config ARCH_SELECT_MEMORY_MODEL
1045 depends on ARCH_SPARSEMEM_ENABLE
1047 config ARCH_MEMORY_PROBE
1049 depends on MEMORY_HOTPLUG
1054 bool "Allocate 3rd-level pagetables from highmem"
1055 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1057 The VM uses one page table entry for each page of physical memory.
1058 For systems with a lot of RAM, this can be wasteful of precious
1059 low memory. Setting this option will put user-space page table
1060 entries in high memory.
1062 config X86_CHECK_BIOS_CORRUPTION
1063 bool "Check for low memory corruption"
1065 Periodically check for memory corruption in low memory, which
1066 is suspected to be caused by BIOS. Even when enabled in the
1067 configuration, it is disabled at runtime. Enable it by
1068 setting "memory_corruption_check=1" on the kernel command
1069 line. By default it scans the low 64k of memory every 60
1070 seconds; see the memory_corruption_check_size and
1071 memory_corruption_check_period parameters in
1072 Documentation/kernel-parameters.txt to adjust this.
1074 When enabled with the default parameters, this option has
1075 almost no overhead, as it reserves a relatively small amount
1076 of memory and scans it infrequently. It both detects corruption
1077 and prevents it from affecting the running system.
1079 It is, however, intended as a diagnostic tool; if repeatable
1080 BIOS-originated corruption always affects the same memory,
1081 you can use memmap= to prevent the kernel from using that
1084 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1085 bool "Set the default setting of memory_corruption_check"
1086 depends on X86_CHECK_BIOS_CORRUPTION
1089 Set whether the default state of memory_corruption_check is
1092 config MATH_EMULATION
1094 prompt "Math emulation" if X86_32
1096 Linux can emulate a math coprocessor (used for floating point
1097 operations) if you don't have one. 486DX and Pentium processors have
1098 a math coprocessor built in, 486SX and 386 do not, unless you added
1099 a 487DX or 387, respectively. (The messages during boot time can
1100 give you some hints here ["man dmesg"].) Everyone needs either a
1101 coprocessor or this emulation.
1103 If you don't have a math coprocessor, you need to say Y here; if you
1104 say Y here even though you have a coprocessor, the coprocessor will
1105 be used nevertheless. (This behavior can be changed with the kernel
1106 command line option "no387", which comes handy if your coprocessor
1107 is broken. Try "man bootparam" or see the documentation of your boot
1108 loader (lilo or loadlin) about how to pass options to the kernel at
1109 boot time.) This means that it is a good idea to say Y here if you
1110 intend to use this kernel on different machines.
1112 More information about the internals of the Linux math coprocessor
1113 emulation can be found in <file:arch/x86/math-emu/README>.
1115 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1116 kernel, it won't hurt.
1119 bool "MTRR (Memory Type Range Register) support"
1121 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1122 the Memory Type Range Registers (MTRRs) may be used to control
1123 processor access to memory ranges. This is most useful if you have
1124 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1125 allows bus write transfers to be combined into a larger transfer
1126 before bursting over the PCI/AGP bus. This can increase performance
1127 of image write operations 2.5 times or more. Saying Y here creates a
1128 /proc/mtrr file which may be used to manipulate your processor's
1129 MTRRs. Typically the X server should use this.
1131 This code has a reasonably generic interface so that similar
1132 control registers on other processors can be easily supported
1135 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1136 Registers (ARRs) which provide a similar functionality to MTRRs. For
1137 these, the ARRs are used to emulate the MTRRs.
1138 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1139 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1140 write-combining. All of these processors are supported by this code
1141 and it makes sense to say Y here if you have one of them.
1143 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1144 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1145 can lead to all sorts of problems, so it's good to say Y here.
1147 You can safely say Y even if your machine doesn't have MTRRs, you'll
1148 just add about 9 KB to your kernel.
1150 See <file:Documentation/mtrr.txt> for more information.
1152 config MTRR_SANITIZER
1154 prompt "MTRR cleanup support"
1157 Convert MTRR layout from continuous to discrete, so X drivers can
1158 add writeback entries.
1160 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1161 The largest mtrr entry size for a continous block can be set with
1166 config MTRR_SANITIZER_ENABLE_DEFAULT
1167 int "MTRR cleanup enable value (0-1)"
1170 depends on MTRR_SANITIZER
1172 Enable mtrr cleanup default value
1174 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1175 int "MTRR cleanup spare reg num (0-7)"
1178 depends on MTRR_SANITIZER
1180 mtrr cleanup spare entries default, it can be changed via
1181 mtrr_spare_reg_nr=N on the kernel command line.
1185 prompt "x86 PAT support"
1188 Use PAT attributes to setup page level cache control.
1190 PATs are the modern equivalents of MTRRs and are much more
1191 flexible than MTRRs.
1193 Say N here if you see bootup problems (boot crash, boot hang,
1194 spontaneous reboots) or a non-working video driver.
1200 prompt "EFI runtime service support"
1203 This enables the kernel to use EFI runtime services that are
1204 available (such as the EFI variable services).
1206 This option is only useful on systems that have EFI firmware.
1207 In addition, you should use the latest ELILO loader available
1208 at <http://elilo.sourceforge.net> in order to take advantage
1209 of EFI runtime services. However, even with this option, the
1210 resultant kernel should continue to boot on existing non-EFI
1215 prompt "Enable kernel irq balancing"
1216 depends on X86_32 && SMP && X86_IO_APIC
1218 The default yes will allow the kernel to do irq load balancing.
1219 Saying no will keep the kernel from doing irq load balancing.
1223 prompt "Enable seccomp to safely compute untrusted bytecode"
1226 This kernel feature is useful for number crunching applications
1227 that may need to compute untrusted bytecode during their
1228 execution. By using pipes or other transports made available to
1229 the process as file descriptors supporting the read/write
1230 syscalls, it's possible to isolate those applications in
1231 their own address space using seccomp. Once seccomp is
1232 enabled via /proc/<pid>/seccomp, it cannot be disabled
1233 and the task is only allowed to execute a few safe syscalls
1234 defined by each seccomp mode.
1236 If unsure, say Y. Only embedded should say N here.
1238 config CC_STACKPROTECTOR
1239 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1240 depends on X86_64 && EXPERIMENTAL && BROKEN
1242 This option turns on the -fstack-protector GCC feature. This
1243 feature puts, at the beginning of critical functions, a canary
1244 value on the stack just before the return address, and validates
1245 the value just before actually returning. Stack based buffer
1246 overflows (that need to overwrite this return address) now also
1247 overwrite the canary, which gets detected and the attack is then
1248 neutralized via a kernel panic.
1250 This feature requires gcc version 4.2 or above, or a distribution
1251 gcc with the feature backported. Older versions are automatically
1252 detected and for those versions, this configuration option is ignored.
1254 config CC_STACKPROTECTOR_ALL
1255 bool "Use stack-protector for all functions"
1256 depends on CC_STACKPROTECTOR
1258 Normally, GCC only inserts the canary value protection for
1259 functions that use large-ish on-stack buffers. By enabling
1260 this option, GCC will be asked to do this for ALL functions.
1262 source kernel/Kconfig.hz
1265 bool "kexec system call"
1266 depends on X86_BIOS_REBOOT
1268 kexec is a system call that implements the ability to shutdown your
1269 current kernel, and to start another kernel. It is like a reboot
1270 but it is independent of the system firmware. And like a reboot
1271 you can start any kernel with it, not just Linux.
1273 The name comes from the similarity to the exec system call.
1275 It is an ongoing process to be certain the hardware in a machine
1276 is properly shutdown, so do not be surprised if this code does not
1277 initially work for you. It may help to enable device hotplugging
1278 support. As of this writing the exact hardware interface is
1279 strongly in flux, so no good recommendation can be made.
1282 bool "kernel crash dumps"
1283 depends on X86_64 || (X86_32 && HIGHMEM)
1285 Generate crash dump after being started by kexec.
1286 This should be normally only set in special crash dump kernels
1287 which are loaded in the main kernel with kexec-tools into
1288 a specially reserved region and then later executed after
1289 a crash by kdump/kexec. The crash dump kernel must be compiled
1290 to a memory address not used by the main kernel or BIOS using
1291 PHYSICAL_START, or it must be built as a relocatable image
1292 (CONFIG_RELOCATABLE=y).
1293 For more details see Documentation/kdump/kdump.txt
1296 bool "kexec jump (EXPERIMENTAL)"
1297 depends on EXPERIMENTAL
1298 depends on KEXEC && HIBERNATION && X86_32
1300 Jump between original kernel and kexeced kernel and invoke
1301 code in physical address mode via KEXEC
1303 config PHYSICAL_START
1304 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1305 default "0x1000000" if X86_NUMAQ
1306 default "0x200000" if X86_64
1309 This gives the physical address where the kernel is loaded.
1311 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1312 bzImage will decompress itself to above physical address and
1313 run from there. Otherwise, bzImage will run from the address where
1314 it has been loaded by the boot loader and will ignore above physical
1317 In normal kdump cases one does not have to set/change this option
1318 as now bzImage can be compiled as a completely relocatable image
1319 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1320 address. This option is mainly useful for the folks who don't want
1321 to use a bzImage for capturing the crash dump and want to use a
1322 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1323 to be specifically compiled to run from a specific memory area
1324 (normally a reserved region) and this option comes handy.
1326 So if you are using bzImage for capturing the crash dump, leave
1327 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1328 Otherwise if you plan to use vmlinux for capturing the crash dump
1329 change this value to start of the reserved region (Typically 16MB
1330 0x1000000). In other words, it can be set based on the "X" value as
1331 specified in the "crashkernel=YM@XM" command line boot parameter
1332 passed to the panic-ed kernel. Typically this parameter is set as
1333 crashkernel=64M@16M. Please take a look at
1334 Documentation/kdump/kdump.txt for more details about crash dumps.
1336 Usage of bzImage for capturing the crash dump is recommended as
1337 one does not have to build two kernels. Same kernel can be used
1338 as production kernel and capture kernel. Above option should have
1339 gone away after relocatable bzImage support is introduced. But it
1340 is present because there are users out there who continue to use
1341 vmlinux for dump capture. This option should go away down the
1344 Don't change this unless you know what you are doing.
1347 bool "Build a relocatable kernel (EXPERIMENTAL)"
1348 depends on EXPERIMENTAL
1350 This builds a kernel image that retains relocation information
1351 so it can be loaded someplace besides the default 1MB.
1352 The relocations tend to make the kernel binary about 10% larger,
1353 but are discarded at runtime.
1355 One use is for the kexec on panic case where the recovery kernel
1356 must live at a different physical address than the primary
1359 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1360 it has been loaded at and the compile time physical address
1361 (CONFIG_PHYSICAL_START) is ignored.
1363 config PHYSICAL_ALIGN
1365 prompt "Alignment value to which kernel should be aligned" if X86_32
1366 default "0x100000" if X86_32
1367 default "0x200000" if X86_64
1368 range 0x2000 0x400000
1370 This value puts the alignment restrictions on physical address
1371 where kernel is loaded and run from. Kernel is compiled for an
1372 address which meets above alignment restriction.
1374 If bootloader loads the kernel at a non-aligned address and
1375 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1376 address aligned to above value and run from there.
1378 If bootloader loads the kernel at a non-aligned address and
1379 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1380 load address and decompress itself to the address it has been
1381 compiled for and run from there. The address for which kernel is
1382 compiled already meets above alignment restrictions. Hence the
1383 end result is that kernel runs from a physical address meeting
1384 above alignment restrictions.
1386 Don't change this unless you know what you are doing.
1389 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1390 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1392 Say Y here to experiment with turning CPUs off and on, and to
1393 enable suspend on SMP systems. CPUs can be controlled through
1394 /sys/devices/system/cpu.
1395 Say N if you want to disable CPU hotplug and don't need to
1400 prompt "Compat VDSO support"
1401 depends on X86_32 || IA32_EMULATION
1403 Map the 32-bit VDSO to the predictable old-style address too.
1405 Say N here if you are running a sufficiently recent glibc
1406 version (2.3.3 or later), to remove the high-mapped
1407 VDSO mapping and to exclusively use the randomized VDSO.
1413 config ARCH_ENABLE_MEMORY_HOTPLUG
1415 depends on X86_64 || (X86_32 && HIGHMEM)
1417 config HAVE_ARCH_EARLY_PFN_TO_NID
1421 menu "Power management options"
1422 depends on !X86_VOYAGER
1424 config ARCH_HIBERNATION_HEADER
1426 depends on X86_64 && HIBERNATION
1428 source "kernel/power/Kconfig"
1430 source "drivers/acpi/Kconfig"
1435 depends on APM || APM_MODULE
1438 tristate "APM (Advanced Power Management) BIOS support"
1439 depends on X86_32 && PM_SLEEP
1441 APM is a BIOS specification for saving power using several different
1442 techniques. This is mostly useful for battery powered laptops with
1443 APM compliant BIOSes. If you say Y here, the system time will be
1444 reset after a RESUME operation, the /proc/apm device will provide
1445 battery status information, and user-space programs will receive
1446 notification of APM "events" (e.g. battery status change).
1448 If you select "Y" here, you can disable actual use of the APM
1449 BIOS by passing the "apm=off" option to the kernel at boot time.
1451 Note that the APM support is almost completely disabled for
1452 machines with more than one CPU.
1454 In order to use APM, you will need supporting software. For location
1455 and more information, read <file:Documentation/power/pm.txt> and the
1456 Battery Powered Linux mini-HOWTO, available from
1457 <http://www.tldp.org/docs.html#howto>.
1459 This driver does not spin down disk drives (see the hdparm(8)
1460 manpage ("man 8 hdparm") for that), and it doesn't turn off
1461 VESA-compliant "green" monitors.
1463 This driver does not support the TI 4000M TravelMate and the ACER
1464 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1465 desktop machines also don't have compliant BIOSes, and this driver
1466 may cause those machines to panic during the boot phase.
1468 Generally, if you don't have a battery in your machine, there isn't
1469 much point in using this driver and you should say N. If you get
1470 random kernel OOPSes or reboots that don't seem to be related to
1471 anything, try disabling/enabling this option (or disabling/enabling
1474 Some other things you should try when experiencing seemingly random,
1477 1) make sure that you have enough swap space and that it is
1479 2) pass the "no-hlt" option to the kernel
1480 3) switch on floating point emulation in the kernel and pass
1481 the "no387" option to the kernel
1482 4) pass the "floppy=nodma" option to the kernel
1483 5) pass the "mem=4M" option to the kernel (thereby disabling
1484 all but the first 4 MB of RAM)
1485 6) make sure that the CPU is not over clocked.
1486 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1487 8) disable the cache from your BIOS settings
1488 9) install a fan for the video card or exchange video RAM
1489 10) install a better fan for the CPU
1490 11) exchange RAM chips
1491 12) exchange the motherboard.
1493 To compile this driver as a module, choose M here: the
1494 module will be called apm.
1498 config APM_IGNORE_USER_SUSPEND
1499 bool "Ignore USER SUSPEND"
1501 This option will ignore USER SUSPEND requests. On machines with a
1502 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1503 series notebooks, it is necessary to say Y because of a BIOS bug.
1505 config APM_DO_ENABLE
1506 bool "Enable PM at boot time"
1508 Enable APM features at boot time. From page 36 of the APM BIOS
1509 specification: "When disabled, the APM BIOS does not automatically
1510 power manage devices, enter the Standby State, enter the Suspend
1511 State, or take power saving steps in response to CPU Idle calls."
1512 This driver will make CPU Idle calls when Linux is idle (unless this
1513 feature is turned off -- see "Do CPU IDLE calls", below). This
1514 should always save battery power, but more complicated APM features
1515 will be dependent on your BIOS implementation. You may need to turn
1516 this option off if your computer hangs at boot time when using APM
1517 support, or if it beeps continuously instead of suspending. Turn
1518 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1519 T400CDT. This is off by default since most machines do fine without
1523 bool "Make CPU Idle calls when idle"
1525 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1526 On some machines, this can activate improved power savings, such as
1527 a slowed CPU clock rate, when the machine is idle. These idle calls
1528 are made after the idle loop has run for some length of time (e.g.,
1529 333 mS). On some machines, this will cause a hang at boot time or
1530 whenever the CPU becomes idle. (On machines with more than one CPU,
1531 this option does nothing.)
1533 config APM_DISPLAY_BLANK
1534 bool "Enable console blanking using APM"
1536 Enable console blanking using the APM. Some laptops can use this to
1537 turn off the LCD backlight when the screen blanker of the Linux
1538 virtual console blanks the screen. Note that this is only used by
1539 the virtual console screen blanker, and won't turn off the backlight
1540 when using the X Window system. This also doesn't have anything to
1541 do with your VESA-compliant power-saving monitor. Further, this
1542 option doesn't work for all laptops -- it might not turn off your
1543 backlight at all, or it might print a lot of errors to the console,
1544 especially if you are using gpm.
1546 config APM_ALLOW_INTS
1547 bool "Allow interrupts during APM BIOS calls"
1549 Normally we disable external interrupts while we are making calls to
1550 the APM BIOS as a measure to lessen the effects of a badly behaving
1551 BIOS implementation. The BIOS should reenable interrupts if it
1552 needs to. Unfortunately, some BIOSes do not -- especially those in
1553 many of the newer IBM Thinkpads. If you experience hangs when you
1554 suspend, try setting this to Y. Otherwise, say N.
1556 config APM_REAL_MODE_POWER_OFF
1557 bool "Use real mode APM BIOS call to power off"
1559 Use real mode APM BIOS calls to switch off the computer. This is
1560 a work-around for a number of buggy BIOSes. Switch this option on if
1561 your computer crashes instead of powering off properly.
1565 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1567 source "drivers/cpuidle/Kconfig"
1572 menu "Bus options (PCI etc.)"
1577 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1579 Find out whether you have a PCI motherboard. PCI is the name of a
1580 bus system, i.e. the way the CPU talks to the other stuff inside
1581 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1582 VESA. If you have PCI, say Y, otherwise N.
1585 prompt "PCI access mode"
1586 depends on X86_32 && PCI
1589 On PCI systems, the BIOS can be used to detect the PCI devices and
1590 determine their configuration. However, some old PCI motherboards
1591 have BIOS bugs and may crash if this is done. Also, some embedded
1592 PCI-based systems don't have any BIOS at all. Linux can also try to
1593 detect the PCI hardware directly without using the BIOS.
1595 With this option, you can specify how Linux should detect the
1596 PCI devices. If you choose "BIOS", the BIOS will be used,
1597 if you choose "Direct", the BIOS won't be used, and if you
1598 choose "MMConfig", then PCI Express MMCONFIG will be used.
1599 If you choose "Any", the kernel will try MMCONFIG, then the
1600 direct access method and falls back to the BIOS if that doesn't
1601 work. If unsure, go with the default, which is "Any".
1606 config PCI_GOMMCONFIG
1623 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1625 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1628 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1632 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1636 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1643 bool "Support mmconfig PCI config space access"
1644 depends on X86_64 && PCI && ACPI
1647 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1648 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1650 DMA remapping (DMAR) devices support enables independent address
1651 translations for Direct Memory Access (DMA) from devices.
1652 These DMA remapping devices are reported via ACPI tables
1653 and include PCI device scope covered by these DMA
1658 prompt "Support for Graphics workaround"
1661 Current Graphics drivers tend to use physical address
1662 for DMA and avoid using DMA APIs. Setting this config
1663 option permits the IOMMU driver to set a unity map for
1664 all the OS-visible memory. Hence the driver can continue
1665 to use physical addresses for DMA.
1667 config DMAR_FLOPPY_WA
1671 Floppy disk drivers are know to bypass DMA API calls
1672 thereby failing to work when IOMMU is enabled. This
1673 workaround will setup a 1:1 mapping for the first
1674 16M to make floppy (an ISA device) work.
1676 source "drivers/pci/pcie/Kconfig"
1678 source "drivers/pci/Kconfig"
1680 # x86_64 have no ISA slots, but do have ISA-style DMA.
1688 depends on !X86_VOYAGER
1690 Find out whether you have ISA slots on your motherboard. ISA is the
1691 name of a bus system, i.e. the way the CPU talks to the other stuff
1692 inside your box. Other bus systems are PCI, EISA, MicroChannel
1693 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1694 newer boards don't support it. If you have ISA, say Y, otherwise N.
1700 The Extended Industry Standard Architecture (EISA) bus was
1701 developed as an open alternative to the IBM MicroChannel bus.
1703 The EISA bus provided some of the features of the IBM MicroChannel
1704 bus while maintaining backward compatibility with cards made for
1705 the older ISA bus. The EISA bus saw limited use between 1988 and
1706 1995 when it was made obsolete by the PCI bus.
1708 Say Y here if you are building a kernel for an EISA-based machine.
1712 source "drivers/eisa/Kconfig"
1715 bool "MCA support" if !X86_VOYAGER
1716 default y if X86_VOYAGER
1718 MicroChannel Architecture is found in some IBM PS/2 machines and
1719 laptops. It is a bus system similar to PCI or ISA. See
1720 <file:Documentation/mca.txt> (and especially the web page given
1721 there) before attempting to build an MCA bus kernel.
1723 source "drivers/mca/Kconfig"
1726 tristate "NatSemi SCx200 support"
1727 depends on !X86_VOYAGER
1729 This provides basic support for National Semiconductor's
1730 (now AMD's) Geode processors. The driver probes for the
1731 PCI-IDs of several on-chip devices, so its a good dependency
1732 for other scx200_* drivers.
1734 If compiled as a module, the driver is named scx200.
1736 config SCx200HR_TIMER
1737 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1738 depends on SCx200 && GENERIC_TIME
1741 This driver provides a clocksource built upon the on-chip
1742 27MHz high-resolution timer. Its also a workaround for
1743 NSC Geode SC-1100's buggy TSC, which loses time when the
1744 processor goes idle (as is done by the scheduler). The
1745 other workaround is idle=poll boot option.
1747 config GEODE_MFGPT_TIMER
1749 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1750 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1752 This driver provides a clock event source based on the MFGPT
1753 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1754 MFGPTs have a better resolution and max interval than the
1755 generic PIT, and are suitable for use as high-res timers.
1758 bool "One Laptop Per Child support"
1761 Add support for detecting the unique features of the OLPC
1768 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1770 source "drivers/pcmcia/Kconfig"
1772 source "drivers/pci/hotplug/Kconfig"
1777 menu "Executable file formats / Emulations"
1779 source "fs/Kconfig.binfmt"
1781 config IA32_EMULATION
1782 bool "IA32 Emulation"
1784 select COMPAT_BINFMT_ELF
1786 Include code to run 32-bit programs under a 64-bit kernel. You should
1787 likely turn this on, unless you're 100% sure that you don't have any
1788 32-bit programs left.
1791 tristate "IA32 a.out support"
1792 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1794 Support old a.out binaries in the 32bit emulation.
1798 depends on IA32_EMULATION
1800 config COMPAT_FOR_U64_ALIGNMENT
1804 config SYSVIPC_COMPAT
1806 depends on X86_64 && COMPAT && SYSVIPC
1811 source "net/Kconfig"
1813 source "drivers/Kconfig"
1815 source "drivers/firmware/Kconfig"
1819 source "arch/x86/Kconfig.debug"
1821 source "security/Kconfig"
1823 source "crypto/Kconfig"
1825 source "arch/x86/kvm/Kconfig"
1827 source "lib/Kconfig"
projects / linux-2.6 / blob