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_ARCH_TRACEHOOK
33 select HAVE_GENERIC_DMA_COHERENT if X86_32
34 select HAVE_EFFICIENT_UNALIGNED_ACCESS
38 default "arch/x86/configs/i386_defconfig" if X86_32
39 default "arch/x86/configs/x86_64_defconfig" if X86_64
42 config GENERIC_LOCKBREAK
48 config GENERIC_CMOS_UPDATE
51 config CLOCKSOURCE_WATCHDOG
54 config GENERIC_CLOCKEVENTS
57 config GENERIC_CLOCKEVENTS_BROADCAST
59 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
61 config LOCKDEP_SUPPORT
64 config STACKTRACE_SUPPORT
67 config HAVE_LATENCYTOP_SUPPORT
70 config FAST_CMPXCHG_LOCAL
83 config GENERIC_ISA_DMA
93 config GENERIC_HWEIGHT
99 config ARCH_MAY_HAVE_PC_FDC
102 config RWSEM_GENERIC_SPINLOCK
105 config RWSEM_XCHGADD_ALGORITHM
108 config ARCH_HAS_ILOG2_U32
111 config ARCH_HAS_ILOG2_U64
114 config ARCH_HAS_CPU_IDLE_WAIT
117 config GENERIC_CALIBRATE_DELAY
120 config GENERIC_TIME_VSYSCALL
124 config ARCH_HAS_CPU_RELAX
127 config ARCH_HAS_CACHE_LINE_SIZE
130 config HAVE_SETUP_PER_CPU_AREA
131 def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER)
133 config HAVE_CPUMASK_OF_CPU_MAP
136 config ARCH_HIBERNATION_POSSIBLE
138 depends on !SMP || !X86_VOYAGER
140 config ARCH_SUSPEND_POSSIBLE
142 depends on !X86_VOYAGER
148 config ARCH_POPULATES_NODE_MAP
155 config ARCH_SUPPORTS_AOUT
158 config ARCH_SUPPORTS_OPTIMIZED_INLINING
161 # Use the generic interrupt handling code in kernel/irq/:
162 config GENERIC_HARDIRQS
166 config GENERIC_IRQ_PROBE
170 config GENERIC_PENDING_IRQ
172 depends on GENERIC_HARDIRQS && SMP
177 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
178 select USE_GENERIC_SMP_HELPERS
183 depends on X86_32 && SMP
187 depends on X86_64 && SMP
192 depends on (X86_32 && !X86_VOYAGER) || X86_64
195 config X86_BIOS_REBOOT
197 depends on !X86_VOYAGER
200 config X86_TRAMPOLINE
202 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
207 source "init/Kconfig"
209 menu "Processor type and features"
211 source "kernel/time/Kconfig"
214 bool "Symmetric multi-processing support"
216 This enables support for systems with more than one CPU. If you have
217 a system with only one CPU, like most personal computers, say N. If
218 you have a system with more than one CPU, say Y.
220 If you say N here, the kernel will run on single and multiprocessor
221 machines, but will use only one CPU of a multiprocessor machine. If
222 you say Y here, the kernel will run on many, but not all,
223 singleprocessor machines. On a singleprocessor machine, the kernel
224 will run faster if you say N here.
226 Note that if you say Y here and choose architecture "586" or
227 "Pentium" under "Processor family", the kernel will not work on 486
228 architectures. Similarly, multiprocessor kernels for the "PPro"
229 architecture may not work on all Pentium based boards.
231 People using multiprocessor machines who say Y here should also say
232 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
233 Management" code will be disabled if you say Y here.
235 See also <file:Documentation/i386/IO-APIC.txt>,
236 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
237 <http://www.tldp.org/docs.html#howto>.
239 If you don't know what to do here, say N.
241 config X86_FIND_SMP_CONFIG
243 depends on X86_MPPARSE || X86_VOYAGER
248 bool "Enable MPS table"
249 depends on X86_LOCAL_APIC
251 For old smp systems that do not have proper acpi support. Newer systems
252 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
258 depends on X86_LOCAL_APIC
262 prompt "Subarchitecture Type"
268 Choose this option if your computer is a standard PC or compatible.
274 Select this for an AMD Elan processor.
276 Do not use this option for K6/Athlon/Opteron processors!
278 If unsure, choose "PC-compatible" instead.
282 depends on X86_32 && (SMP || BROKEN) && !PCI
284 Voyager is an MCA-based 32-way capable SMP architecture proprietary
285 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
289 If you do not specifically know you have a Voyager based machine,
290 say N here, otherwise the kernel you build will not be bootable.
292 config X86_GENERICARCH
293 bool "Generic architecture"
296 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
297 subarchitectures. It is intended for a generic binary kernel.
298 if you select them all, kernel will probe it one by one. and will
304 bool "NUMAQ (IBM/Sequent)"
305 depends on SMP && X86_32 && PCI && X86_MPPARSE
308 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
309 NUMA multiquad box. This changes the way that processors are
310 bootstrapped, and uses Clustered Logical APIC addressing mode instead
311 of Flat Logical. You will need a new lynxer.elf file to flash your
312 firmware with - send email to <Martin.Bligh@us.ibm.com>.
315 bool "Summit/EXA (IBM x440)"
316 depends on X86_32 && SMP
318 This option is needed for IBM systems that use the Summit/EXA chipset.
319 In particular, it is needed for the x440.
322 bool "Support for Unisys ES7000 IA32 series"
323 depends on X86_32 && SMP
325 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
326 supposed to run on an IA32-based Unisys ES7000 system.
329 bool "Support for big SMP systems with more than 8 CPUs"
330 depends on X86_32 && SMP
332 This option is needed for the systems that have more than 8 CPUs
333 and if the system is not of any sub-arch type above.
338 bool "Support for ScaleMP vSMP"
340 depends on X86_64 && PCI
342 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
343 supposed to run on these EM64T-based machines. Only choose this option
344 if you have one of these machines.
349 bool "SGI 320/540 (Visual Workstation)"
350 depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT
352 The SGI Visual Workstation series is an IA32-based workstation
353 based on SGI systems chips with some legacy PC hardware attached.
355 Say Y here to create a kernel to run on the SGI 320 or 540.
357 A kernel compiled for the Visual Workstation will run on general
358 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
361 bool "RDC R-321x SoC"
364 select X86_REBOOTFIXUPS
366 This option is needed for RDC R-321x system-on-chip, also known
368 If you don't have one of these chips, you should say N here.
370 config SCHED_NO_NO_OMIT_FRAME_POINTER
372 prompt "Single-depth WCHAN output"
375 Calculate simpler /proc/<PID>/wchan values. If this option
376 is disabled then wchan values will recurse back to the
377 caller function. This provides more accurate wchan values,
378 at the expense of slightly more scheduling overhead.
380 If in doubt, say "Y".
382 menuconfig PARAVIRT_GUEST
383 bool "Paravirtualized guest support"
385 Say Y here to get to see options related to running Linux under
386 various hypervisors. This option alone does not add any kernel code.
388 If you say N, all options in this submenu will be skipped and disabled.
392 source "arch/x86/xen/Kconfig"
395 bool "VMI Guest support"
398 depends on !X86_VOYAGER
400 VMI provides a paravirtualized interface to the VMware ESX server
401 (it could be used by other hypervisors in theory too, but is not
402 at the moment), by linking the kernel to a GPL-ed ROM module
403 provided by the hypervisor.
406 bool "KVM paravirtualized clock"
408 select PARAVIRT_CLOCK
409 depends on !X86_VOYAGER
411 Turning on this option will allow you to run a paravirtualized clock
412 when running over the KVM hypervisor. Instead of relying on a PIT
413 (or probably other) emulation by the underlying device model, the host
414 provides the guest with timing infrastructure such as time of day, and
418 bool "KVM Guest support"
420 depends on !X86_VOYAGER
422 This option enables various optimizations for running under the KVM
425 source "arch/x86/lguest/Kconfig"
428 bool "Enable paravirtualization code"
429 depends on !X86_VOYAGER
431 This changes the kernel so it can modify itself when it is run
432 under a hypervisor, potentially improving performance significantly
433 over full virtualization. However, when run without a hypervisor
434 the kernel is theoretically slower and slightly larger.
436 config PARAVIRT_CLOCK
442 config PARAVIRT_DEBUG
443 bool "paravirt-ops debugging"
444 depends on PARAVIRT && DEBUG_KERNEL
446 Enable to debug paravirt_ops internals. Specifically, BUG if
447 a paravirt_op is missing when it is called.
452 This option adds a kernel parameter 'memtest', which allows memtest
454 memtest=0, mean disabled; -- default
455 memtest=1, mean do 1 test pattern;
457 memtest=4, mean do 4 test patterns.
458 If you are unsure how to answer this question, answer N.
460 config X86_SUMMIT_NUMA
462 depends on X86_32 && NUMA && X86_GENERICARCH
464 config X86_CYCLONE_TIMER
466 depends on X86_GENERICARCH
468 config ES7000_CLUSTERED_APIC
470 depends on SMP && X86_ES7000 && MPENTIUMIII
472 source "arch/x86/Kconfig.cpu"
476 prompt "HPET Timer Support" if X86_32
478 Use the IA-PC HPET (High Precision Event Timer) to manage
479 time in preference to the PIT and RTC, if a HPET is
481 HPET is the next generation timer replacing legacy 8254s.
482 The HPET provides a stable time base on SMP
483 systems, unlike the TSC, but it is more expensive to access,
484 as it is off-chip. You can find the HPET spec at
485 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
487 You can safely choose Y here. However, HPET will only be
488 activated if the platform and the BIOS support this feature.
489 Otherwise the 8254 will be used for timing services.
491 Choose N to continue using the legacy 8254 timer.
493 config HPET_EMULATE_RTC
495 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
497 # Mark as embedded because too many people got it wrong.
498 # The code disables itself when not needed.
501 bool "Enable DMI scanning" if EMBEDDED
503 Enabled scanning of DMI to identify machine quirks. Say Y
504 here unless you have verified that your setup is not
505 affected by entries in the DMI blacklist. Required by PNP
509 bool "GART IOMMU support" if EMBEDDED
513 depends on X86_64 && PCI
515 Support for full DMA access of devices with 32bit memory access only
516 on systems with more than 3GB. This is usually needed for USB,
517 sound, many IDE/SATA chipsets and some other devices.
518 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
519 based hardware IOMMU and a software bounce buffer based IOMMU used
520 on Intel systems and as fallback.
521 The code is only active when needed (enough memory and limited
522 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
526 bool "IBM Calgary IOMMU support"
528 depends on X86_64 && PCI && EXPERIMENTAL
530 Support for hardware IOMMUs in IBM's xSeries x366 and x460
531 systems. Needed to run systems with more than 3GB of memory
532 properly with 32-bit PCI devices that do not support DAC
533 (Double Address Cycle). Calgary also supports bus level
534 isolation, where all DMAs pass through the IOMMU. This
535 prevents them from going anywhere except their intended
536 destination. This catches hard-to-find kernel bugs and
537 mis-behaving drivers and devices that do not use the DMA-API
538 properly to set up their DMA buffers. The IOMMU can be
539 turned off at boot time with the iommu=off parameter.
540 Normally the kernel will make the right choice by itself.
543 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
545 prompt "Should Calgary be enabled by default?"
546 depends on CALGARY_IOMMU
548 Should Calgary be enabled by default? if you choose 'y', Calgary
549 will be used (if it exists). If you choose 'n', Calgary will not be
550 used even if it exists. If you choose 'n' and would like to use
551 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
555 bool "AMD IOMMU support"
557 depends on X86_64 && PCI && ACPI
559 With this option you can enable support for AMD IOMMU hardware in
560 your system. An IOMMU is a hardware component which provides
561 remapping of DMA memory accesses from devices. With an AMD IOMMU you
562 can isolate the the DMA memory of different devices and protect the
563 system from misbehaving device drivers or hardware.
565 You can find out if your system has an AMD IOMMU if you look into
566 your BIOS for an option to enable it or if you have an IVRS ACPI
569 # need this always selected by IOMMU for the VIA workaround
573 Support for software bounce buffers used on x86-64 systems
574 which don't have a hardware IOMMU (e.g. the current generation
575 of Intel's x86-64 CPUs). Using this PCI devices which can only
576 access 32-bits of memory can be used on systems with more than
577 3 GB of memory. If unsure, say Y.
580 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
583 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
584 depends on X86_64 && SMP && BROKEN
587 Configure maximum number of CPUS and NUMA Nodes for this architecture.
591 int "Maximum number of CPUs (2-512)" if !MAXSMP
594 default "4096" if MAXSMP
595 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
598 This allows you to specify the maximum number of CPUs which this
599 kernel will support. The maximum supported value is 512 and the
600 minimum value which makes sense is 2.
602 This is purely to save memory - each supported CPU adds
603 approximately eight kilobytes to the kernel image.
606 bool "SMT (Hyperthreading) scheduler support"
609 SMT scheduler support improves the CPU scheduler's decision making
610 when dealing with Intel Pentium 4 chips with HyperThreading at a
611 cost of slightly increased overhead in some places. If unsure say
616 prompt "Multi-core scheduler support"
619 Multi-core scheduler support improves the CPU scheduler's decision
620 making when dealing with multi-core CPU chips at a cost of slightly
621 increased overhead in some places. If unsure say N here.
623 source "kernel/Kconfig.preempt"
626 bool "Local APIC support on uniprocessors"
627 depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH)
629 A local APIC (Advanced Programmable Interrupt Controller) is an
630 integrated interrupt controller in the CPU. If you have a single-CPU
631 system which has a processor with a local APIC, you can say Y here to
632 enable and use it. If you say Y here even though your machine doesn't
633 have a local APIC, then the kernel will still run with no slowdown at
634 all. The local APIC supports CPU-generated self-interrupts (timer,
635 performance counters), and the NMI watchdog which detects hard
639 bool "IO-APIC support on uniprocessors"
640 depends on X86_UP_APIC
642 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
643 SMP-capable replacement for PC-style interrupt controllers. Most
644 SMP systems and many recent uniprocessor systems have one.
646 If you have a single-CPU system with an IO-APIC, you can say Y here
647 to use it. If you say Y here even though your machine doesn't have
648 an IO-APIC, then the kernel will still run with no slowdown at all.
650 config X86_LOCAL_APIC
652 depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
656 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
658 config X86_VISWS_APIC
660 depends on X86_32 && X86_VISWS
663 bool "Machine Check Exception"
664 depends on !X86_VOYAGER
666 Machine Check Exception support allows the processor to notify the
667 kernel if it detects a problem (e.g. overheating, component failure).
668 The action the kernel takes depends on the severity of the problem,
669 ranging from a warning message on the console, to halting the machine.
670 Your processor must be a Pentium or newer to support this - check the
671 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
672 have a design flaw which leads to false MCE events - hence MCE is
673 disabled on all P5 processors, unless explicitly enabled with "mce"
674 as a boot argument. Similarly, if MCE is built in and creates a
675 problem on some new non-standard machine, you can boot with "nomce"
676 to disable it. MCE support simply ignores non-MCE processors like
677 the 386 and 486, so nearly everyone can say Y here.
681 prompt "Intel MCE features"
682 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
684 Additional support for intel specific MCE features such as
689 prompt "AMD MCE features"
690 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
692 Additional support for AMD specific MCE features such as
693 the DRAM Error Threshold.
695 config X86_MCE_NONFATAL
696 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
697 depends on X86_32 && X86_MCE
699 Enabling this feature starts a timer that triggers every 5 seconds which
700 will look at the machine check registers to see if anything happened.
701 Non-fatal problems automatically get corrected (but still logged).
702 Disable this if you don't want to see these messages.
703 Seeing the messages this option prints out may be indicative of dying
704 or out-of-spec (ie, overclocked) hardware.
705 This option only does something on certain CPUs.
706 (AMD Athlon/Duron and Intel Pentium 4)
708 config X86_MCE_P4THERMAL
709 bool "check for P4 thermal throttling interrupt."
710 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
712 Enabling this feature will cause a message to be printed when the P4
713 enters thermal throttling.
716 bool "Enable VM86 support" if EMBEDDED
720 This option is required by programs like DOSEMU to run 16-bit legacy
721 code on X86 processors. It also may be needed by software like
722 XFree86 to initialize some video cards via BIOS. Disabling this
723 option saves about 6k.
726 tristate "Toshiba Laptop support"
729 This adds a driver to safely access the System Management Mode of
730 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
731 not work on models with a Phoenix BIOS. The System Management Mode
732 is used to set the BIOS and power saving options on Toshiba portables.
734 For information on utilities to make use of this driver see the
735 Toshiba Linux utilities web site at:
736 <http://www.buzzard.org.uk/toshiba/>.
738 Say Y if you intend to run this kernel on a Toshiba portable.
742 tristate "Dell laptop support"
744 This adds a driver to safely access the System Management Mode
745 of the CPU on the Dell Inspiron 8000. The System Management Mode
746 is used to read cpu temperature and cooling fan status and to
747 control the fans on the I8K portables.
749 This driver has been tested only on the Inspiron 8000 but it may
750 also work with other Dell laptops. You can force loading on other
751 models by passing the parameter `force=1' to the module. Use at
754 For information on utilities to make use of this driver see the
755 I8K Linux utilities web site at:
756 <http://people.debian.org/~dz/i8k/>
758 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
761 config X86_REBOOTFIXUPS
763 prompt "Enable X86 board specific fixups for reboot"
764 depends on X86_32 && X86
766 This enables chipset and/or board specific fixups to be done
767 in order to get reboot to work correctly. This is only needed on
768 some combinations of hardware and BIOS. The symptom, for which
769 this config is intended, is when reboot ends with a stalled/hung
772 Currently, the only fixup is for the Geode machines using
773 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
775 Say Y if you want to enable the fixup. Currently, it's safe to
776 enable this option even if you don't need it.
780 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
783 If you say Y here, you will be able to update the microcode on
784 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
785 Pentium III, Pentium 4, Xeon etc. You will obviously need the
786 actual microcode binary data itself which is not shipped with the
789 For latest news and information on obtaining all the required
790 ingredients for this driver, check:
791 <http://www.urbanmyth.org/microcode/>.
793 To compile this driver as a module, choose M here: the
794 module will be called microcode.
796 config MICROCODE_OLD_INTERFACE
801 tristate "/dev/cpu/*/msr - Model-specific register support"
803 This device gives privileged processes access to the x86
804 Model-Specific Registers (MSRs). It is a character device with
805 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
806 MSR accesses are directed to a specific CPU on multi-processor
810 tristate "/dev/cpu/*/cpuid - CPU information support"
812 This device gives processes access to the x86 CPUID instruction to
813 be executed on a specific processor. It is a character device
814 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
818 prompt "High Memory Support"
819 default HIGHMEM4G if !X86_NUMAQ
820 default HIGHMEM64G if X86_NUMAQ
825 depends on !X86_NUMAQ
827 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
828 However, the address space of 32-bit x86 processors is only 4
829 Gigabytes large. That means that, if you have a large amount of
830 physical memory, not all of it can be "permanently mapped" by the
831 kernel. The physical memory that's not permanently mapped is called
834 If you are compiling a kernel which will never run on a machine with
835 more than 1 Gigabyte total physical RAM, answer "off" here (default
836 choice and suitable for most users). This will result in a "3GB/1GB"
837 split: 3GB are mapped so that each process sees a 3GB virtual memory
838 space and the remaining part of the 4GB virtual memory space is used
839 by the kernel to permanently map as much physical memory as
842 If the machine has between 1 and 4 Gigabytes physical RAM, then
845 If more than 4 Gigabytes is used then answer "64GB" here. This
846 selection turns Intel PAE (Physical Address Extension) mode on.
847 PAE implements 3-level paging on IA32 processors. PAE is fully
848 supported by Linux, PAE mode is implemented on all recent Intel
849 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
850 then the kernel will not boot on CPUs that don't support PAE!
852 The actual amount of total physical memory will either be
853 auto detected or can be forced by using a kernel command line option
854 such as "mem=256M". (Try "man bootparam" or see the documentation of
855 your boot loader (lilo or loadlin) about how to pass options to the
856 kernel at boot time.)
858 If unsure, say "off".
862 depends on !X86_NUMAQ
864 Select this if you have a 32-bit processor and between 1 and 4
865 gigabytes of physical RAM.
869 depends on !M386 && !M486
872 Select this if you have a 32-bit processor and more than 4
873 gigabytes of physical RAM.
878 depends on EXPERIMENTAL
879 prompt "Memory split" if EMBEDDED
883 Select the desired split between kernel and user memory.
885 If the address range available to the kernel is less than the
886 physical memory installed, the remaining memory will be available
887 as "high memory". Accessing high memory is a little more costly
888 than low memory, as it needs to be mapped into the kernel first.
889 Note that increasing the kernel address space limits the range
890 available to user programs, making the address space there
891 tighter. Selecting anything other than the default 3G/1G split
892 will also likely make your kernel incompatible with binary-only
895 If you are not absolutely sure what you are doing, leave this
899 bool "3G/1G user/kernel split"
900 config VMSPLIT_3G_OPT
902 bool "3G/1G user/kernel split (for full 1G low memory)"
904 bool "2G/2G user/kernel split"
905 config VMSPLIT_2G_OPT
907 bool "2G/2G user/kernel split (for full 2G low memory)"
909 bool "1G/3G user/kernel split"
914 default 0xB0000000 if VMSPLIT_3G_OPT
915 default 0x80000000 if VMSPLIT_2G
916 default 0x78000000 if VMSPLIT_2G_OPT
917 default 0x40000000 if VMSPLIT_1G
923 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
927 prompt "PAE (Physical Address Extension) Support"
928 depends on X86_32 && !HIGHMEM4G
929 select RESOURCES_64BIT
931 PAE is required for NX support, and furthermore enables
932 larger swapspace support for non-overcommit purposes. It
933 has the cost of more pagetable lookup overhead, and also
934 consumes more pagetable space per process.
936 # Common NUMA Features
938 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
940 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
942 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
944 Enable NUMA (Non Uniform Memory Access) support.
945 The kernel will try to allocate memory used by a CPU on the
946 local memory controller of the CPU and add some more
947 NUMA awareness to the kernel.
949 For 32-bit this is currently highly experimental and should be only
950 used for kernel development. It might also cause boot failures.
951 For 64-bit this is recommended on all multiprocessor Opteron systems.
952 If the system is EM64T, you should say N unless your system is
955 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
956 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
960 prompt "Old style AMD Opteron NUMA detection"
961 depends on X86_64 && NUMA && PCI
963 Enable K8 NUMA node topology detection. You should say Y here if
964 you have a multi processor AMD K8 system. This uses an old
965 method to read the NUMA configuration directly from the builtin
966 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
967 instead, which also takes priority if both are compiled in.
969 config X86_64_ACPI_NUMA
971 prompt "ACPI NUMA detection"
972 depends on X86_64 && NUMA && ACPI && PCI
975 Enable ACPI SRAT based node topology detection.
977 # Some NUMA nodes have memory ranges that span
978 # other nodes. Even though a pfn is valid and
979 # between a node's start and end pfns, it may not
980 # reside on that node. See memmap_init_zone()
982 config NODES_SPAN_OTHER_NODES
984 depends on X86_64_ACPI_NUMA
987 bool "NUMA emulation"
988 depends on X86_64 && NUMA
990 Enable NUMA emulation. A flat machine will be split
991 into virtual nodes when booted with "numa=fake=N", where N is the
992 number of nodes. This is only useful for debugging.
995 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
997 default "9" if MAXSMP
998 default "6" if X86_64
999 default "4" if X86_NUMAQ
1001 depends on NEED_MULTIPLE_NODES
1003 Specify the maximum number of NUMA Nodes available on the target
1004 system. Increases memory reserved to accomodate various tables.
1006 config HAVE_ARCH_BOOTMEM_NODE
1008 depends on X86_32 && NUMA
1010 config ARCH_HAVE_MEMORY_PRESENT
1012 depends on X86_32 && DISCONTIGMEM
1014 config NEED_NODE_MEMMAP_SIZE
1016 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1018 config HAVE_ARCH_ALLOC_REMAP
1020 depends on X86_32 && NUMA
1022 config ARCH_FLATMEM_ENABLE
1024 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1026 config ARCH_DISCONTIGMEM_ENABLE
1028 depends on NUMA && X86_32
1030 config ARCH_DISCONTIGMEM_DEFAULT
1032 depends on NUMA && X86_32
1034 config ARCH_SPARSEMEM_DEFAULT
1038 config ARCH_SPARSEMEM_ENABLE
1040 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC) || X86_GENERICARCH
1041 select SPARSEMEM_STATIC if X86_32
1042 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1044 config ARCH_SELECT_MEMORY_MODEL
1046 depends on ARCH_SPARSEMEM_ENABLE
1048 config ARCH_MEMORY_PROBE
1050 depends on MEMORY_HOTPLUG
1055 bool "Allocate 3rd-level pagetables from highmem"
1056 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1058 The VM uses one page table entry for each page of physical memory.
1059 For systems with a lot of RAM, this can be wasteful of precious
1060 low memory. Setting this option will put user-space page table
1061 entries in high memory.
1063 config MATH_EMULATION
1065 prompt "Math emulation" if X86_32
1067 Linux can emulate a math coprocessor (used for floating point
1068 operations) if you don't have one. 486DX and Pentium processors have
1069 a math coprocessor built in, 486SX and 386 do not, unless you added
1070 a 487DX or 387, respectively. (The messages during boot time can
1071 give you some hints here ["man dmesg"].) Everyone needs either a
1072 coprocessor or this emulation.
1074 If you don't have a math coprocessor, you need to say Y here; if you
1075 say Y here even though you have a coprocessor, the coprocessor will
1076 be used nevertheless. (This behavior can be changed with the kernel
1077 command line option "no387", which comes handy if your coprocessor
1078 is broken. Try "man bootparam" or see the documentation of your boot
1079 loader (lilo or loadlin) about how to pass options to the kernel at
1080 boot time.) This means that it is a good idea to say Y here if you
1081 intend to use this kernel on different machines.
1083 More information about the internals of the Linux math coprocessor
1084 emulation can be found in <file:arch/x86/math-emu/README>.
1086 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1087 kernel, it won't hurt.
1090 bool "MTRR (Memory Type Range Register) support"
1092 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1093 the Memory Type Range Registers (MTRRs) may be used to control
1094 processor access to memory ranges. This is most useful if you have
1095 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1096 allows bus write transfers to be combined into a larger transfer
1097 before bursting over the PCI/AGP bus. This can increase performance
1098 of image write operations 2.5 times or more. Saying Y here creates a
1099 /proc/mtrr file which may be used to manipulate your processor's
1100 MTRRs. Typically the X server should use this.
1102 This code has a reasonably generic interface so that similar
1103 control registers on other processors can be easily supported
1106 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1107 Registers (ARRs) which provide a similar functionality to MTRRs. For
1108 these, the ARRs are used to emulate the MTRRs.
1109 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1110 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1111 write-combining. All of these processors are supported by this code
1112 and it makes sense to say Y here if you have one of them.
1114 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1115 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1116 can lead to all sorts of problems, so it's good to say Y here.
1118 You can safely say Y even if your machine doesn't have MTRRs, you'll
1119 just add about 9 KB to your kernel.
1121 See <file:Documentation/x86/mtrr.txt> for more information.
1123 config MTRR_SANITIZER
1125 prompt "MTRR cleanup support"
1128 Convert MTRR layout from continuous to discrete, so X drivers can
1129 add writeback entries.
1131 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1132 The largest mtrr entry size for a continous block can be set with
1137 config MTRR_SANITIZER_ENABLE_DEFAULT
1138 int "MTRR cleanup enable value (0-1)"
1141 depends on MTRR_SANITIZER
1143 Enable mtrr cleanup default value
1145 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1146 int "MTRR cleanup spare reg num (0-7)"
1149 depends on MTRR_SANITIZER
1151 mtrr cleanup spare entries default, it can be changed via
1152 mtrr_spare_reg_nr=N on the kernel command line.
1156 prompt "x86 PAT support"
1159 Use PAT attributes to setup page level cache control.
1161 PATs are the modern equivalents of MTRRs and are much more
1162 flexible than MTRRs.
1164 Say N here if you see bootup problems (boot crash, boot hang,
1165 spontaneous reboots) or a non-working video driver.
1171 prompt "EFI runtime service support"
1174 This enables the kernel to use EFI runtime services that are
1175 available (such as the EFI variable services).
1177 This option is only useful on systems that have EFI firmware.
1178 In addition, you should use the latest ELILO loader available
1179 at <http://elilo.sourceforge.net> in order to take advantage
1180 of EFI runtime services. However, even with this option, the
1181 resultant kernel should continue to boot on existing non-EFI
1186 prompt "Enable kernel irq balancing"
1187 depends on X86_32 && SMP && X86_IO_APIC
1189 The default yes will allow the kernel to do irq load balancing.
1190 Saying no will keep the kernel from doing irq load balancing.
1194 prompt "Enable seccomp to safely compute untrusted bytecode"
1196 This kernel feature is useful for number crunching applications
1197 that may need to compute untrusted bytecode during their
1198 execution. By using pipes or other transports made available to
1199 the process as file descriptors supporting the read/write
1200 syscalls, it's possible to isolate those applications in
1201 their own address space using seccomp. Once seccomp is
1202 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1203 and the task is only allowed to execute a few safe syscalls
1204 defined by each seccomp mode.
1206 If unsure, say Y. Only embedded should say N here.
1208 config CC_STACKPROTECTOR
1209 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1210 depends on X86_64 && EXPERIMENTAL && BROKEN
1212 This option turns on the -fstack-protector GCC feature. This
1213 feature puts, at the beginning of critical functions, a canary
1214 value on the stack just before the return address, and validates
1215 the value just before actually returning. Stack based buffer
1216 overflows (that need to overwrite this return address) now also
1217 overwrite the canary, which gets detected and the attack is then
1218 neutralized via a kernel panic.
1220 This feature requires gcc version 4.2 or above, or a distribution
1221 gcc with the feature backported. Older versions are automatically
1222 detected and for those versions, this configuration option is ignored.
1224 config CC_STACKPROTECTOR_ALL
1225 bool "Use stack-protector for all functions"
1226 depends on CC_STACKPROTECTOR
1228 Normally, GCC only inserts the canary value protection for
1229 functions that use large-ish on-stack buffers. By enabling
1230 this option, GCC will be asked to do this for ALL functions.
1232 source kernel/Kconfig.hz
1235 bool "kexec system call"
1236 depends on X86_BIOS_REBOOT
1238 kexec is a system call that implements the ability to shutdown your
1239 current kernel, and to start another kernel. It is like a reboot
1240 but it is independent of the system firmware. And like a reboot
1241 you can start any kernel with it, not just Linux.
1243 The name comes from the similarity to the exec system call.
1245 It is an ongoing process to be certain the hardware in a machine
1246 is properly shutdown, so do not be surprised if this code does not
1247 initially work for you. It may help to enable device hotplugging
1248 support. As of this writing the exact hardware interface is
1249 strongly in flux, so no good recommendation can be made.
1252 bool "kernel crash dumps"
1253 depends on X86_64 || (X86_32 && HIGHMEM)
1255 Generate crash dump after being started by kexec.
1256 This should be normally only set in special crash dump kernels
1257 which are loaded in the main kernel with kexec-tools into
1258 a specially reserved region and then later executed after
1259 a crash by kdump/kexec. The crash dump kernel must be compiled
1260 to a memory address not used by the main kernel or BIOS using
1261 PHYSICAL_START, or it must be built as a relocatable image
1262 (CONFIG_RELOCATABLE=y).
1263 For more details see Documentation/kdump/kdump.txt
1266 bool "kexec jump (EXPERIMENTAL)"
1267 depends on EXPERIMENTAL
1268 depends on KEXEC && HIBERNATION && X86_32
1270 Jump between original kernel and kexeced kernel and invoke
1271 code in physical address mode via KEXEC
1273 config PHYSICAL_START
1274 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1275 default "0x1000000" if X86_NUMAQ
1276 default "0x200000" if X86_64
1279 This gives the physical address where the kernel is loaded.
1281 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1282 bzImage will decompress itself to above physical address and
1283 run from there. Otherwise, bzImage will run from the address where
1284 it has been loaded by the boot loader and will ignore above physical
1287 In normal kdump cases one does not have to set/change this option
1288 as now bzImage can be compiled as a completely relocatable image
1289 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1290 address. This option is mainly useful for the folks who don't want
1291 to use a bzImage for capturing the crash dump and want to use a
1292 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1293 to be specifically compiled to run from a specific memory area
1294 (normally a reserved region) and this option comes handy.
1296 So if you are using bzImage for capturing the crash dump, leave
1297 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1298 Otherwise if you plan to use vmlinux for capturing the crash dump
1299 change this value to start of the reserved region (Typically 16MB
1300 0x1000000). In other words, it can be set based on the "X" value as
1301 specified in the "crashkernel=YM@XM" command line boot parameter
1302 passed to the panic-ed kernel. Typically this parameter is set as
1303 crashkernel=64M@16M. Please take a look at
1304 Documentation/kdump/kdump.txt for more details about crash dumps.
1306 Usage of bzImage for capturing the crash dump is recommended as
1307 one does not have to build two kernels. Same kernel can be used
1308 as production kernel and capture kernel. Above option should have
1309 gone away after relocatable bzImage support is introduced. But it
1310 is present because there are users out there who continue to use
1311 vmlinux for dump capture. This option should go away down the
1314 Don't change this unless you know what you are doing.
1317 bool "Build a relocatable kernel (EXPERIMENTAL)"
1318 depends on EXPERIMENTAL
1320 This builds a kernel image that retains relocation information
1321 so it can be loaded someplace besides the default 1MB.
1322 The relocations tend to make the kernel binary about 10% larger,
1323 but are discarded at runtime.
1325 One use is for the kexec on panic case where the recovery kernel
1326 must live at a different physical address than the primary
1329 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1330 it has been loaded at and the compile time physical address
1331 (CONFIG_PHYSICAL_START) is ignored.
1333 config PHYSICAL_ALIGN
1335 prompt "Alignment value to which kernel should be aligned" if X86_32
1336 default "0x100000" if X86_32
1337 default "0x200000" if X86_64
1338 range 0x2000 0x400000
1340 This value puts the alignment restrictions on physical address
1341 where kernel is loaded and run from. Kernel is compiled for an
1342 address which meets above alignment restriction.
1344 If bootloader loads the kernel at a non-aligned address and
1345 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1346 address aligned to above value and run from there.
1348 If bootloader loads the kernel at a non-aligned address and
1349 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1350 load address and decompress itself to the address it has been
1351 compiled for and run from there. The address for which kernel is
1352 compiled already meets above alignment restrictions. Hence the
1353 end result is that kernel runs from a physical address meeting
1354 above alignment restrictions.
1356 Don't change this unless you know what you are doing.
1359 bool "Support for hot-pluggable CPUs"
1360 depends on SMP && HOTPLUG && !X86_VOYAGER
1362 Say Y here to allow turning CPUs off and on. CPUs can be
1363 controlled through /sys/devices/system/cpu.
1364 ( Note: power management support will enable this option
1365 automatically on SMP systems. )
1366 Say N if you want to disable CPU hotplug.
1370 prompt "Compat VDSO support"
1371 depends on X86_32 || IA32_EMULATION
1373 Map the 32-bit VDSO to the predictable old-style address too.
1375 Say N here if you are running a sufficiently recent glibc
1376 version (2.3.3 or later), to remove the high-mapped
1377 VDSO mapping and to exclusively use the randomized VDSO.
1382 bool "Built-in kernel command line"
1385 Allow for specifying boot arguments to the kernel at
1386 build time. On some systems (e.g. embedded ones), it is
1387 necessary or convenient to provide some or all of the
1388 kernel boot arguments with the kernel itself (that is,
1389 to not rely on the boot loader to provide them.)
1391 To compile command line arguments into the kernel,
1392 set this option to 'Y', then fill in the
1393 the boot arguments in CONFIG_CMDLINE.
1395 Systems with fully functional boot loaders (i.e. non-embedded)
1396 should leave this option set to 'N'.
1399 string "Built-in kernel command string"
1400 depends on CMDLINE_BOOL
1403 Enter arguments here that should be compiled into the kernel
1404 image and used at boot time. If the boot loader provides a
1405 command line at boot time, it is appended to this string to
1406 form the full kernel command line, when the system boots.
1408 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1409 change this behavior.
1411 In most cases, the command line (whether built-in or provided
1412 by the boot loader) should specify the device for the root
1415 config CMDLINE_OVERRIDE
1416 bool "Built-in command line overrides boot loader arguments"
1418 depends on CMDLINE_BOOL
1420 Set this option to 'Y' to have the kernel ignore the boot loader
1421 command line, and use ONLY the built-in command line.
1423 This is used to work around broken boot loaders. This should
1424 be set to 'N' under normal conditions.
1428 config ARCH_ENABLE_MEMORY_HOTPLUG
1430 depends on X86_64 || (X86_32 && HIGHMEM)
1432 config HAVE_ARCH_EARLY_PFN_TO_NID
1436 menu "Power management options"
1437 depends on !X86_VOYAGER
1439 config ARCH_HIBERNATION_HEADER
1441 depends on X86_64 && HIBERNATION
1443 source "kernel/power/Kconfig"
1445 source "drivers/acpi/Kconfig"
1450 depends on APM || APM_MODULE
1453 tristate "APM (Advanced Power Management) BIOS support"
1454 depends on X86_32 && PM_SLEEP
1456 APM is a BIOS specification for saving power using several different
1457 techniques. This is mostly useful for battery powered laptops with
1458 APM compliant BIOSes. If you say Y here, the system time will be
1459 reset after a RESUME operation, the /proc/apm device will provide
1460 battery status information, and user-space programs will receive
1461 notification of APM "events" (e.g. battery status change).
1463 If you select "Y" here, you can disable actual use of the APM
1464 BIOS by passing the "apm=off" option to the kernel at boot time.
1466 Note that the APM support is almost completely disabled for
1467 machines with more than one CPU.
1469 In order to use APM, you will need supporting software. For location
1470 and more information, read <file:Documentation/power/pm.txt> and the
1471 Battery Powered Linux mini-HOWTO, available from
1472 <http://www.tldp.org/docs.html#howto>.
1474 This driver does not spin down disk drives (see the hdparm(8)
1475 manpage ("man 8 hdparm") for that), and it doesn't turn off
1476 VESA-compliant "green" monitors.
1478 This driver does not support the TI 4000M TravelMate and the ACER
1479 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1480 desktop machines also don't have compliant BIOSes, and this driver
1481 may cause those machines to panic during the boot phase.
1483 Generally, if you don't have a battery in your machine, there isn't
1484 much point in using this driver and you should say N. If you get
1485 random kernel OOPSes or reboots that don't seem to be related to
1486 anything, try disabling/enabling this option (or disabling/enabling
1489 Some other things you should try when experiencing seemingly random,
1492 1) make sure that you have enough swap space and that it is
1494 2) pass the "no-hlt" option to the kernel
1495 3) switch on floating point emulation in the kernel and pass
1496 the "no387" option to the kernel
1497 4) pass the "floppy=nodma" option to the kernel
1498 5) pass the "mem=4M" option to the kernel (thereby disabling
1499 all but the first 4 MB of RAM)
1500 6) make sure that the CPU is not over clocked.
1501 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1502 8) disable the cache from your BIOS settings
1503 9) install a fan for the video card or exchange video RAM
1504 10) install a better fan for the CPU
1505 11) exchange RAM chips
1506 12) exchange the motherboard.
1508 To compile this driver as a module, choose M here: the
1509 module will be called apm.
1513 config APM_IGNORE_USER_SUSPEND
1514 bool "Ignore USER SUSPEND"
1516 This option will ignore USER SUSPEND requests. On machines with a
1517 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1518 series notebooks, it is necessary to say Y because of a BIOS bug.
1520 config APM_DO_ENABLE
1521 bool "Enable PM at boot time"
1523 Enable APM features at boot time. From page 36 of the APM BIOS
1524 specification: "When disabled, the APM BIOS does not automatically
1525 power manage devices, enter the Standby State, enter the Suspend
1526 State, or take power saving steps in response to CPU Idle calls."
1527 This driver will make CPU Idle calls when Linux is idle (unless this
1528 feature is turned off -- see "Do CPU IDLE calls", below). This
1529 should always save battery power, but more complicated APM features
1530 will be dependent on your BIOS implementation. You may need to turn
1531 this option off if your computer hangs at boot time when using APM
1532 support, or if it beeps continuously instead of suspending. Turn
1533 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1534 T400CDT. This is off by default since most machines do fine without
1538 bool "Make CPU Idle calls when idle"
1540 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1541 On some machines, this can activate improved power savings, such as
1542 a slowed CPU clock rate, when the machine is idle. These idle calls
1543 are made after the idle loop has run for some length of time (e.g.,
1544 333 mS). On some machines, this will cause a hang at boot time or
1545 whenever the CPU becomes idle. (On machines with more than one CPU,
1546 this option does nothing.)
1548 config APM_DISPLAY_BLANK
1549 bool "Enable console blanking using APM"
1551 Enable console blanking using the APM. Some laptops can use this to
1552 turn off the LCD backlight when the screen blanker of the Linux
1553 virtual console blanks the screen. Note that this is only used by
1554 the virtual console screen blanker, and won't turn off the backlight
1555 when using the X Window system. This also doesn't have anything to
1556 do with your VESA-compliant power-saving monitor. Further, this
1557 option doesn't work for all laptops -- it might not turn off your
1558 backlight at all, or it might print a lot of errors to the console,
1559 especially if you are using gpm.
1561 config APM_ALLOW_INTS
1562 bool "Allow interrupts during APM BIOS calls"
1564 Normally we disable external interrupts while we are making calls to
1565 the APM BIOS as a measure to lessen the effects of a badly behaving
1566 BIOS implementation. The BIOS should reenable interrupts if it
1567 needs to. Unfortunately, some BIOSes do not -- especially those in
1568 many of the newer IBM Thinkpads. If you experience hangs when you
1569 suspend, try setting this to Y. Otherwise, say N.
1571 config APM_REAL_MODE_POWER_OFF
1572 bool "Use real mode APM BIOS call to power off"
1574 Use real mode APM BIOS calls to switch off the computer. This is
1575 a work-around for a number of buggy BIOSes. Switch this option on if
1576 your computer crashes instead of powering off properly.
1580 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1582 source "drivers/cpuidle/Kconfig"
1587 menu "Bus options (PCI etc.)"
1592 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1594 Find out whether you have a PCI motherboard. PCI is the name of a
1595 bus system, i.e. the way the CPU talks to the other stuff inside
1596 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1597 VESA. If you have PCI, say Y, otherwise N.
1600 prompt "PCI access mode"
1601 depends on X86_32 && PCI
1604 On PCI systems, the BIOS can be used to detect the PCI devices and
1605 determine their configuration. However, some old PCI motherboards
1606 have BIOS bugs and may crash if this is done. Also, some embedded
1607 PCI-based systems don't have any BIOS at all. Linux can also try to
1608 detect the PCI hardware directly without using the BIOS.
1610 With this option, you can specify how Linux should detect the
1611 PCI devices. If you choose "BIOS", the BIOS will be used,
1612 if you choose "Direct", the BIOS won't be used, and if you
1613 choose "MMConfig", then PCI Express MMCONFIG will be used.
1614 If you choose "Any", the kernel will try MMCONFIG, then the
1615 direct access method and falls back to the BIOS if that doesn't
1616 work. If unsure, go with the default, which is "Any".
1621 config PCI_GOMMCONFIG
1638 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1640 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1643 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1647 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1651 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1658 bool "Support mmconfig PCI config space access"
1659 depends on X86_64 && PCI && ACPI
1662 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1663 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1665 DMA remapping (DMAR) devices support enables independent address
1666 translations for Direct Memory Access (DMA) from devices.
1667 These DMA remapping devices are reported via ACPI tables
1668 and include PCI device scope covered by these DMA
1673 prompt "Support for Graphics workaround"
1676 Current Graphics drivers tend to use physical address
1677 for DMA and avoid using DMA APIs. Setting this config
1678 option permits the IOMMU driver to set a unity map for
1679 all the OS-visible memory. Hence the driver can continue
1680 to use physical addresses for DMA.
1682 config DMAR_FLOPPY_WA
1686 Floppy disk drivers are know to bypass DMA API calls
1687 thereby failing to work when IOMMU is enabled. This
1688 workaround will setup a 1:1 mapping for the first
1689 16M to make floppy (an ISA device) work.
1691 source "drivers/pci/pcie/Kconfig"
1693 source "drivers/pci/Kconfig"
1695 # x86_64 have no ISA slots, but do have ISA-style DMA.
1703 depends on !X86_VOYAGER
1705 Find out whether you have ISA slots on your motherboard. ISA is the
1706 name of a bus system, i.e. the way the CPU talks to the other stuff
1707 inside your box. Other bus systems are PCI, EISA, MicroChannel
1708 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1709 newer boards don't support it. If you have ISA, say Y, otherwise N.
1715 The Extended Industry Standard Architecture (EISA) bus was
1716 developed as an open alternative to the IBM MicroChannel bus.
1718 The EISA bus provided some of the features of the IBM MicroChannel
1719 bus while maintaining backward compatibility with cards made for
1720 the older ISA bus. The EISA bus saw limited use between 1988 and
1721 1995 when it was made obsolete by the PCI bus.
1723 Say Y here if you are building a kernel for an EISA-based machine.
1727 source "drivers/eisa/Kconfig"
1730 bool "MCA support" if !X86_VOYAGER
1731 default y if X86_VOYAGER
1733 MicroChannel Architecture is found in some IBM PS/2 machines and
1734 laptops. It is a bus system similar to PCI or ISA. See
1735 <file:Documentation/mca.txt> (and especially the web page given
1736 there) before attempting to build an MCA bus kernel.
1738 source "drivers/mca/Kconfig"
1741 tristate "NatSemi SCx200 support"
1742 depends on !X86_VOYAGER
1744 This provides basic support for National Semiconductor's
1745 (now AMD's) Geode processors. The driver probes for the
1746 PCI-IDs of several on-chip devices, so its a good dependency
1747 for other scx200_* drivers.
1749 If compiled as a module, the driver is named scx200.
1751 config SCx200HR_TIMER
1752 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1753 depends on SCx200 && GENERIC_TIME
1756 This driver provides a clocksource built upon the on-chip
1757 27MHz high-resolution timer. Its also a workaround for
1758 NSC Geode SC-1100's buggy TSC, which loses time when the
1759 processor goes idle (as is done by the scheduler). The
1760 other workaround is idle=poll boot option.
1762 config GEODE_MFGPT_TIMER
1764 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1765 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1767 This driver provides a clock event source based on the MFGPT
1768 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1769 MFGPTs have a better resolution and max interval than the
1770 generic PIT, and are suitable for use as high-res timers.
1773 bool "One Laptop Per Child support"
1776 Add support for detecting the unique features of the OLPC
1783 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1785 source "drivers/pcmcia/Kconfig"
1787 source "drivers/pci/hotplug/Kconfig"
1792 menu "Executable file formats / Emulations"
1794 source "fs/Kconfig.binfmt"
1796 config IA32_EMULATION
1797 bool "IA32 Emulation"
1799 select COMPAT_BINFMT_ELF
1801 Include code to run 32-bit programs under a 64-bit kernel. You should
1802 likely turn this on, unless you're 100% sure that you don't have any
1803 32-bit programs left.
1806 tristate "IA32 a.out support"
1807 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1809 Support old a.out binaries in the 32bit emulation.
1813 depends on IA32_EMULATION
1815 config COMPAT_FOR_U64_ALIGNMENT
1819 config SYSVIPC_COMPAT
1821 depends on COMPAT && SYSVIPC
1826 source "net/Kconfig"
1828 source "drivers/Kconfig"
1830 source "drivers/firmware/Kconfig"
1834 source "arch/x86/Kconfig.debug"
1836 source "security/Kconfig"
1838 source "crypto/Kconfig"
1840 source "arch/x86/kvm/Kconfig"
1842 source "lib/Kconfig"
projects / deliverable / linux.git / blob