2 mainmenu "Linux Kernel Configuration for x86"
6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
9 Say yes to build a 64-bit kernel - formerly known as x86_64
10 Say no to build a 32-bit kernel - formerly known as i386
21 select HAVE_UNSTABLE_SCHED_CLOCK
25 select HAVE_KRETPROBES
26 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
27 select HAVE_ARCH_KGDB if !X86_VOYAGER
31 default "arch/x86/configs/i386_defconfig" if X86_32
32 default "arch/x86/configs/x86_64_defconfig" if X86_64
35 config GENERIC_LOCKBREAK
41 config GENERIC_CMOS_UPDATE
44 config CLOCKSOURCE_WATCHDOG
47 config GENERIC_CLOCKEVENTS
50 config GENERIC_CLOCKEVENTS_BROADCAST
52 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
54 config LOCKDEP_SUPPORT
57 config STACKTRACE_SUPPORT
60 config HAVE_LATENCYTOP_SUPPORT
63 config FAST_CMPXCHG_LOCAL
76 config GENERIC_ISA_DMA
86 config GENERIC_HWEIGHT
92 config ARCH_MAY_HAVE_PC_FDC
95 config RWSEM_GENERIC_SPINLOCK
98 config RWSEM_XCHGADD_ALGORITHM
101 config ARCH_HAS_ILOG2_U32
104 config ARCH_HAS_ILOG2_U64
107 config ARCH_HAS_CPU_IDLE_WAIT
110 config GENERIC_CALIBRATE_DELAY
113 config GENERIC_TIME_VSYSCALL
117 config ARCH_HAS_CPU_RELAX
120 config ARCH_HAS_CACHE_LINE_SIZE
123 config HAVE_SETUP_PER_CPU_AREA
124 def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
126 config HAVE_CPUMASK_OF_CPU_MAP
129 config ARCH_HIBERNATION_POSSIBLE
131 depends on !SMP || !X86_VOYAGER
133 config ARCH_SUSPEND_POSSIBLE
135 depends on !X86_VOYAGER
141 config ARCH_POPULATES_NODE_MAP
148 config ARCH_SUPPORTS_AOUT
151 config ARCH_SUPPORTS_OPTIMIZED_INLINING
154 # Use the generic interrupt handling code in kernel/irq/:
155 config GENERIC_HARDIRQS
159 config GENERIC_IRQ_PROBE
163 config GENERIC_PENDING_IRQ
165 depends on GENERIC_HARDIRQS && SMP
170 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
175 depends on X86_32 && SMP
179 depends on X86_64 && SMP
184 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
187 config X86_BIOS_REBOOT
189 depends on !X86_VISWS && !X86_VOYAGER
192 config X86_TRAMPOLINE
194 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
199 source "init/Kconfig"
201 menu "Processor type and features"
203 source "kernel/time/Kconfig"
206 bool "Symmetric multi-processing support"
208 This enables support for systems with more than one CPU. If you have
209 a system with only one CPU, like most personal computers, say N. If
210 you have a system with more than one CPU, say Y.
212 If you say N here, the kernel will run on single and multiprocessor
213 machines, but will use only one CPU of a multiprocessor machine. If
214 you say Y here, the kernel will run on many, but not all,
215 singleprocessor machines. On a singleprocessor machine, the kernel
216 will run faster if you say N here.
218 Note that if you say Y here and choose architecture "586" or
219 "Pentium" under "Processor family", the kernel will not work on 486
220 architectures. Similarly, multiprocessor kernels for the "PPro"
221 architecture may not work on all Pentium based boards.
223 People using multiprocessor machines who say Y here should also say
224 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
225 Management" code will be disabled if you say Y here.
227 See also <file:Documentation/i386/IO-APIC.txt>,
228 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
229 <http://www.tldp.org/docs.html#howto>.
231 If you don't know what to do here, say N.
233 config X86_FIND_SMP_CONFIG
235 depends on X86_MPPARSE || X86_VOYAGER || X86_VISWS
241 bool "Enable MPS table"
242 depends on X86_LOCAL_APIC && !X86_VISWS
244 For old smp systems that do not have proper acpi support. Newer systems
245 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
251 depends on X86_LOCAL_APIC && !X86_VISWS
255 prompt "Subarchitecture Type"
261 Choose this option if your computer is a standard PC or compatible.
267 Select this for an AMD Elan processor.
269 Do not use this option for K6/Athlon/Opteron processors!
271 If unsure, choose "PC-compatible" instead.
275 depends on X86_32 && (SMP || BROKEN) && !PCI
277 Voyager is an MCA-based 32-way capable SMP architecture proprietary
278 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
282 If you do not specifically know you have a Voyager based machine,
283 say N here, otherwise the kernel you build will not be bootable.
286 bool "SGI 320/540 (Visual Workstation)"
287 depends on X86_32 && !PCI
289 The SGI Visual Workstation series is an IA32-based workstation
290 based on SGI systems chips with some legacy PC hardware attached.
292 Say Y here to create a kernel to run on the SGI 320 or 540.
294 A kernel compiled for the Visual Workstation will not run on PCs
295 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
297 config X86_GENERICARCH
298 bool "Generic architecture"
301 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
302 subarchitectures. It is intended for a generic binary kernel.
303 if you select them all, kernel will probe it one by one. and will
309 bool "NUMAQ (IBM/Sequent)"
310 depends on SMP && X86_32 && PCI && X86_MPPARSE
313 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
314 NUMA multiquad box. This changes the way that processors are
315 bootstrapped, and uses Clustered Logical APIC addressing mode instead
316 of Flat Logical. You will need a new lynxer.elf file to flash your
317 firmware with - send email to <Martin.Bligh@us.ibm.com>.
320 bool "Summit/EXA (IBM x440)"
321 depends on X86_32 && SMP
323 This option is needed for IBM systems that use the Summit/EXA chipset.
324 In particular, it is needed for the x440.
327 bool "Support for Unisys ES7000 IA32 series"
328 depends on X86_32 && SMP
330 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
331 supposed to run on an IA32-based Unisys ES7000 system.
334 bool "Support for big SMP systems with more than 8 CPUs"
335 depends on X86_32 && SMP
337 This option is needed for the systems that have more than 8 CPUs
338 and if the system is not of any sub-arch type above.
343 bool "RDC R-321x SoC"
346 select X86_REBOOTFIXUPS
352 This option is needed for RDC R-321x system-on-chip, also known
354 If you don't have one of these chips, you should say N here.
357 bool "Support for ScaleMP vSMP"
359 depends on X86_64 && !PCI
361 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
362 supposed to run on these EM64T-based machines. Only choose this option
363 if you have one of these machines.
367 config SCHED_NO_NO_OMIT_FRAME_POINTER
369 prompt "Single-depth WCHAN output"
372 Calculate simpler /proc/<PID>/wchan values. If this option
373 is disabled then wchan values will recurse back to the
374 caller function. This provides more accurate wchan values,
375 at the expense of slightly more scheduling overhead.
377 If in doubt, say "Y".
379 menuconfig PARAVIRT_GUEST
380 bool "Paravirtualized guest support"
382 Say Y here to get to see options related to running Linux under
383 various hypervisors. This option alone does not add any kernel code.
385 If you say N, all options in this submenu will be skipped and disabled.
389 source "arch/x86/xen/Kconfig"
392 bool "VMI Guest support"
395 depends on !(X86_VISWS || X86_VOYAGER)
397 VMI provides a paravirtualized interface to the VMware ESX server
398 (it could be used by other hypervisors in theory too, but is not
399 at the moment), by linking the kernel to a GPL-ed ROM module
400 provided by the hypervisor.
403 bool "KVM paravirtualized clock"
405 select PARAVIRT_CLOCK
406 depends on !(X86_VISWS || X86_VOYAGER)
408 Turning on this option will allow you to run a paravirtualized clock
409 when running over the KVM hypervisor. Instead of relying on a PIT
410 (or probably other) emulation by the underlying device model, the host
411 provides the guest with timing infrastructure such as time of day, and
415 bool "KVM Guest support"
417 depends on !(X86_VISWS || X86_VOYAGER)
419 This option enables various optimizations for running under the KVM
422 source "arch/x86/lguest/Kconfig"
425 bool "Enable paravirtualization code"
426 depends on !(X86_VISWS || X86_VOYAGER)
428 This changes the kernel so it can modify itself when it is run
429 under a hypervisor, potentially improving performance significantly
430 over full virtualization. However, when run without a hypervisor
431 the kernel is theoretically slower and slightly larger.
433 config PARAVIRT_CLOCK
444 This option adds a kernel parameter 'memtest', which allows memtest
446 memtest=0, mean disabled; -- default
447 memtest=1, mean do 1 test pattern;
449 memtest=4, mean do 4 test patterns.
450 If you are unsure how to answer this question, answer Y.
454 depends on X86_32 && ACPI && NUMA && X86_GENERICARCH
457 config HAVE_ARCH_PARSE_SRAT
461 config X86_SUMMIT_NUMA
463 depends on X86_32 && NUMA && X86_GENERICARCH
465 config X86_CYCLONE_TIMER
467 depends on X86_GENERICARCH
469 config ES7000_CLUSTERED_APIC
471 depends on SMP && X86_ES7000 && MPENTIUMIII
473 source "arch/x86/Kconfig.cpu"
477 prompt "HPET Timer Support" if X86_32
479 Use the IA-PC HPET (High Precision Event Timer) to manage
480 time in preference to the PIT and RTC, if a HPET is
482 HPET is the next generation timer replacing legacy 8254s.
483 The HPET provides a stable time base on SMP
484 systems, unlike the TSC, but it is more expensive to access,
485 as it is off-chip. You can find the HPET spec at
486 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
488 You can safely choose Y here. However, HPET will only be
489 activated if the platform and the BIOS support this feature.
490 Otherwise the 8254 will be used for timing services.
492 Choose N to continue using the legacy 8254 timer.
494 config HPET_EMULATE_RTC
496 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
498 # Mark as embedded because too many people got it wrong.
499 # The code disables itself when not needed.
502 bool "Enable DMI scanning" if EMBEDDED
504 Enabled scanning of DMI to identify machine quirks. Say Y
505 here unless you have verified that your setup is not
506 affected by entries in the DMI blacklist. Required by PNP
510 bool "GART IOMMU support" if EMBEDDED
514 depends on X86_64 && PCI
516 Support for full DMA access of devices with 32bit memory access only
517 on systems with more than 3GB. This is usually needed for USB,
518 sound, many IDE/SATA chipsets and some other devices.
519 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
520 based hardware IOMMU and a software bounce buffer based IOMMU used
521 on Intel systems and as fallback.
522 The code is only active when needed (enough memory and limited
523 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
527 bool "IBM Calgary IOMMU support"
529 depends on X86_64 && PCI && EXPERIMENTAL
531 Support for hardware IOMMUs in IBM's xSeries x366 and x460
532 systems. Needed to run systems with more than 3GB of memory
533 properly with 32-bit PCI devices that do not support DAC
534 (Double Address Cycle). Calgary also supports bus level
535 isolation, where all DMAs pass through the IOMMU. This
536 prevents them from going anywhere except their intended
537 destination. This catches hard-to-find kernel bugs and
538 mis-behaving drivers and devices that do not use the DMA-API
539 properly to set up their DMA buffers. The IOMMU can be
540 turned off at boot time with the iommu=off parameter.
541 Normally the kernel will make the right choice by itself.
544 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
546 prompt "Should Calgary be enabled by default?"
547 depends on CALGARY_IOMMU
549 Should Calgary be enabled by default? if you choose 'y', Calgary
550 will be used (if it exists). If you choose 'n', Calgary will not be
551 used even if it exists. If you choose 'n' and would like to use
552 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
556 bool "AMD IOMMU support"
558 depends on X86_64 && PCI && ACPI
560 With this option you can enable support for AMD IOMMU hardware in
561 your system. An IOMMU is a hardware component which provides
562 remapping of DMA memory accesses from devices. With an AMD IOMMU you
563 can isolate the the DMA memory of different devices and protect the
564 system from misbehaving device drivers or hardware.
566 You can find out if your system has an AMD IOMMU if you look into
567 your BIOS for an option to enable it or if you have an IVRS ACPI
570 # need this always selected by IOMMU for the VIA workaround
574 Support for software bounce buffers used on x86-64 systems
575 which don't have a hardware IOMMU (e.g. the current generation
576 of Intel's x86-64 CPUs). Using this PCI devices which can only
577 access 32-bits of memory can be used on systems with more than
578 3 GB of memory. If unsure, say Y.
581 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
584 int "Maximum number of CPUs (2-4096)"
587 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
590 This allows you to specify the maximum number of CPUs which this
591 kernel will support. The maximum supported value is 4096 and the
592 minimum value which makes sense is 2.
594 This is purely to save memory - each supported CPU adds
595 approximately one kilobyte to the kernel image.
598 bool "SMT (Hyperthreading) scheduler support"
601 SMT scheduler support improves the CPU scheduler's decision making
602 when dealing with Intel Pentium 4 chips with HyperThreading at a
603 cost of slightly increased overhead in some places. If unsure say
608 prompt "Multi-core scheduler support"
611 Multi-core scheduler support improves the CPU scheduler's decision
612 making when dealing with multi-core CPU chips at a cost of slightly
613 increased overhead in some places. If unsure say N here.
615 source "kernel/Kconfig.preempt"
618 bool "Local APIC support on uniprocessors"
619 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
621 A local APIC (Advanced Programmable Interrupt Controller) is an
622 integrated interrupt controller in the CPU. If you have a single-CPU
623 system which has a processor with a local APIC, you can say Y here to
624 enable and use it. If you say Y here even though your machine doesn't
625 have a local APIC, then the kernel will still run with no slowdown at
626 all. The local APIC supports CPU-generated self-interrupts (timer,
627 performance counters), and the NMI watchdog which detects hard
631 bool "IO-APIC support on uniprocessors"
632 depends on X86_UP_APIC
634 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
635 SMP-capable replacement for PC-style interrupt controllers. Most
636 SMP systems and many recent uniprocessor systems have one.
638 If you have a single-CPU system with an IO-APIC, you can say Y here
639 to use it. If you say Y here even though your machine doesn't have
640 an IO-APIC, then the kernel will still run with no slowdown at all.
642 config X86_LOCAL_APIC
644 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
648 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
650 config X86_VISWS_APIC
652 depends on X86_32 && X86_VISWS
655 bool "Machine Check Exception"
656 depends on !X86_VOYAGER
658 Machine Check Exception support allows the processor to notify the
659 kernel if it detects a problem (e.g. overheating, component failure).
660 The action the kernel takes depends on the severity of the problem,
661 ranging from a warning message on the console, to halting the machine.
662 Your processor must be a Pentium or newer to support this - check the
663 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
664 have a design flaw which leads to false MCE events - hence MCE is
665 disabled on all P5 processors, unless explicitly enabled with "mce"
666 as a boot argument. Similarly, if MCE is built in and creates a
667 problem on some new non-standard machine, you can boot with "nomce"
668 to disable it. MCE support simply ignores non-MCE processors like
669 the 386 and 486, so nearly everyone can say Y here.
673 prompt "Intel MCE features"
674 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
676 Additional support for intel specific MCE features such as
681 prompt "AMD MCE features"
682 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
684 Additional support for AMD specific MCE features such as
685 the DRAM Error Threshold.
687 config X86_MCE_NONFATAL
688 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
689 depends on X86_32 && X86_MCE
691 Enabling this feature starts a timer that triggers every 5 seconds which
692 will look at the machine check registers to see if anything happened.
693 Non-fatal problems automatically get corrected (but still logged).
694 Disable this if you don't want to see these messages.
695 Seeing the messages this option prints out may be indicative of dying
696 or out-of-spec (ie, overclocked) hardware.
697 This option only does something on certain CPUs.
698 (AMD Athlon/Duron and Intel Pentium 4)
700 config X86_MCE_P4THERMAL
701 bool "check for P4 thermal throttling interrupt."
702 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
704 Enabling this feature will cause a message to be printed when the P4
705 enters thermal throttling.
708 bool "Enable VM86 support" if EMBEDDED
712 This option is required by programs like DOSEMU to run 16-bit legacy
713 code on X86 processors. It also may be needed by software like
714 XFree86 to initialize some video cards via BIOS. Disabling this
715 option saves about 6k.
718 tristate "Toshiba Laptop support"
721 This adds a driver to safely access the System Management Mode of
722 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
723 not work on models with a Phoenix BIOS. The System Management Mode
724 is used to set the BIOS and power saving options on Toshiba portables.
726 For information on utilities to make use of this driver see the
727 Toshiba Linux utilities web site at:
728 <http://www.buzzard.org.uk/toshiba/>.
730 Say Y if you intend to run this kernel on a Toshiba portable.
734 tristate "Dell laptop support"
736 This adds a driver to safely access the System Management Mode
737 of the CPU on the Dell Inspiron 8000. The System Management Mode
738 is used to read cpu temperature and cooling fan status and to
739 control the fans on the I8K portables.
741 This driver has been tested only on the Inspiron 8000 but it may
742 also work with other Dell laptops. You can force loading on other
743 models by passing the parameter `force=1' to the module. Use at
746 For information on utilities to make use of this driver see the
747 I8K Linux utilities web site at:
748 <http://people.debian.org/~dz/i8k/>
750 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
753 config X86_REBOOTFIXUPS
755 prompt "Enable X86 board specific fixups for reboot"
756 depends on X86_32 && X86
758 This enables chipset and/or board specific fixups to be done
759 in order to get reboot to work correctly. This is only needed on
760 some combinations of hardware and BIOS. The symptom, for which
761 this config is intended, is when reboot ends with a stalled/hung
764 Currently, the only fixup is for the Geode machines using
765 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
767 Say Y if you want to enable the fixup. Currently, it's safe to
768 enable this option even if you don't need it.
772 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
775 If you say Y here, you will be able to update the microcode on
776 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
777 Pentium III, Pentium 4, Xeon etc. You will obviously need the
778 actual microcode binary data itself which is not shipped with the
781 For latest news and information on obtaining all the required
782 ingredients for this driver, check:
783 <http://www.urbanmyth.org/microcode/>.
785 To compile this driver as a module, choose M here: the
786 module will be called microcode.
788 config MICROCODE_OLD_INTERFACE
793 tristate "/dev/cpu/*/msr - Model-specific register support"
795 This device gives privileged processes access to the x86
796 Model-Specific Registers (MSRs). It is a character device with
797 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
798 MSR accesses are directed to a specific CPU on multi-processor
802 tristate "/dev/cpu/*/cpuid - CPU information support"
804 This device gives processes access to the x86 CPUID instruction to
805 be executed on a specific processor. It is a character device
806 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
810 prompt "High Memory Support"
811 default HIGHMEM4G if !X86_NUMAQ
812 default HIGHMEM64G if X86_NUMAQ
817 depends on !X86_NUMAQ
819 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
820 However, the address space of 32-bit x86 processors is only 4
821 Gigabytes large. That means that, if you have a large amount of
822 physical memory, not all of it can be "permanently mapped" by the
823 kernel. The physical memory that's not permanently mapped is called
826 If you are compiling a kernel which will never run on a machine with
827 more than 1 Gigabyte total physical RAM, answer "off" here (default
828 choice and suitable for most users). This will result in a "3GB/1GB"
829 split: 3GB are mapped so that each process sees a 3GB virtual memory
830 space and the remaining part of the 4GB virtual memory space is used
831 by the kernel to permanently map as much physical memory as
834 If the machine has between 1 and 4 Gigabytes physical RAM, then
837 If more than 4 Gigabytes is used then answer "64GB" here. This
838 selection turns Intel PAE (Physical Address Extension) mode on.
839 PAE implements 3-level paging on IA32 processors. PAE is fully
840 supported by Linux, PAE mode is implemented on all recent Intel
841 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
842 then the kernel will not boot on CPUs that don't support PAE!
844 The actual amount of total physical memory will either be
845 auto detected or can be forced by using a kernel command line option
846 such as "mem=256M". (Try "man bootparam" or see the documentation of
847 your boot loader (lilo or loadlin) about how to pass options to the
848 kernel at boot time.)
850 If unsure, say "off".
854 depends on !X86_NUMAQ
856 Select this if you have a 32-bit processor and between 1 and 4
857 gigabytes of physical RAM.
861 depends on !M386 && !M486
864 Select this if you have a 32-bit processor and more than 4
865 gigabytes of physical RAM.
870 depends on EXPERIMENTAL
871 prompt "Memory split" if EMBEDDED
875 Select the desired split between kernel and user memory.
877 If the address range available to the kernel is less than the
878 physical memory installed, the remaining memory will be available
879 as "high memory". Accessing high memory is a little more costly
880 than low memory, as it needs to be mapped into the kernel first.
881 Note that increasing the kernel address space limits the range
882 available to user programs, making the address space there
883 tighter. Selecting anything other than the default 3G/1G split
884 will also likely make your kernel incompatible with binary-only
887 If you are not absolutely sure what you are doing, leave this
891 bool "3G/1G user/kernel split"
892 config VMSPLIT_3G_OPT
894 bool "3G/1G user/kernel split (for full 1G low memory)"
896 bool "2G/2G user/kernel split"
897 config VMSPLIT_2G_OPT
899 bool "2G/2G user/kernel split (for full 2G low memory)"
901 bool "1G/3G user/kernel split"
906 default 0xB0000000 if VMSPLIT_3G_OPT
907 default 0x80000000 if VMSPLIT_2G
908 default 0x78000000 if VMSPLIT_2G_OPT
909 default 0x40000000 if VMSPLIT_1G
915 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
919 prompt "PAE (Physical Address Extension) Support"
920 depends on X86_32 && !HIGHMEM4G
921 select RESOURCES_64BIT
923 PAE is required for NX support, and furthermore enables
924 larger swapspace support for non-overcommit purposes. It
925 has the cost of more pagetable lookup overhead, and also
926 consumes more pagetable space per process.
928 # Common NUMA Features
930 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
932 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
934 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
936 Enable NUMA (Non Uniform Memory Access) support.
937 The kernel will try to allocate memory used by a CPU on the
938 local memory controller of the CPU and add some more
939 NUMA awareness to the kernel.
941 For i386 this is currently highly experimental and should be only
942 used for kernel development. It might also cause boot failures.
943 For x86_64 this is recommended on all multiprocessor Opteron systems.
944 If the system is EM64T, you should say N unless your system is
947 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
948 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
952 prompt "Old style AMD Opteron NUMA detection"
953 depends on X86_64 && NUMA && PCI
955 Enable K8 NUMA node topology detection. You should say Y here if
956 you have a multi processor AMD K8 system. This uses an old
957 method to read the NUMA configuration directly from the builtin
958 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
959 instead, which also takes priority if both are compiled in.
961 config X86_64_ACPI_NUMA
963 prompt "ACPI NUMA detection"
964 depends on X86_64 && NUMA && ACPI && PCI
967 Enable ACPI SRAT based node topology detection.
969 # Some NUMA nodes have memory ranges that span
970 # other nodes. Even though a pfn is valid and
971 # between a node's start and end pfns, it may not
972 # reside on that node. See memmap_init_zone()
974 config NODES_SPAN_OTHER_NODES
976 depends on X86_64_ACPI_NUMA
979 bool "NUMA emulation"
980 depends on X86_64 && NUMA
982 Enable NUMA emulation. A flat machine will be split
983 into virtual nodes when booted with "numa=fake=N", where N is the
984 number of nodes. This is only useful for debugging.
987 int "Max num nodes shift(1-9)"
989 default "6" if X86_64
990 default "4" if X86_NUMAQ
992 depends on NEED_MULTIPLE_NODES
994 config HAVE_ARCH_BOOTMEM_NODE
996 depends on X86_32 && NUMA
998 config ARCH_HAVE_MEMORY_PRESENT
1000 depends on X86_32 && DISCONTIGMEM
1002 config NEED_NODE_MEMMAP_SIZE
1004 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1006 config HAVE_ARCH_ALLOC_REMAP
1008 depends on X86_32 && NUMA
1010 config ARCH_FLATMEM_ENABLE
1012 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
1014 config ARCH_DISCONTIGMEM_ENABLE
1016 depends on NUMA && X86_32
1018 config ARCH_DISCONTIGMEM_DEFAULT
1020 depends on NUMA && X86_32
1022 config ARCH_SPARSEMEM_DEFAULT
1026 config ARCH_SPARSEMEM_ENABLE
1028 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1029 select SPARSEMEM_STATIC if X86_32
1030 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1032 config ARCH_SELECT_MEMORY_MODEL
1034 depends on ARCH_SPARSEMEM_ENABLE
1036 config ARCH_MEMORY_PROBE
1038 depends on MEMORY_HOTPLUG
1043 bool "Allocate 3rd-level pagetables from highmem"
1044 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1046 The VM uses one page table entry for each page of physical memory.
1047 For systems with a lot of RAM, this can be wasteful of precious
1048 low memory. Setting this option will put user-space page table
1049 entries in high memory.
1051 config MATH_EMULATION
1053 prompt "Math emulation" if X86_32
1055 Linux can emulate a math coprocessor (used for floating point
1056 operations) if you don't have one. 486DX and Pentium processors have
1057 a math coprocessor built in, 486SX and 386 do not, unless you added
1058 a 487DX or 387, respectively. (The messages during boot time can
1059 give you some hints here ["man dmesg"].) Everyone needs either a
1060 coprocessor or this emulation.
1062 If you don't have a math coprocessor, you need to say Y here; if you
1063 say Y here even though you have a coprocessor, the coprocessor will
1064 be used nevertheless. (This behavior can be changed with the kernel
1065 command line option "no387", which comes handy if your coprocessor
1066 is broken. Try "man bootparam" or see the documentation of your boot
1067 loader (lilo or loadlin) about how to pass options to the kernel at
1068 boot time.) This means that it is a good idea to say Y here if you
1069 intend to use this kernel on different machines.
1071 More information about the internals of the Linux math coprocessor
1072 emulation can be found in <file:arch/x86/math-emu/README>.
1074 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1075 kernel, it won't hurt.
1078 bool "MTRR (Memory Type Range Register) support"
1080 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1081 the Memory Type Range Registers (MTRRs) may be used to control
1082 processor access to memory ranges. This is most useful if you have
1083 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1084 allows bus write transfers to be combined into a larger transfer
1085 before bursting over the PCI/AGP bus. This can increase performance
1086 of image write operations 2.5 times or more. Saying Y here creates a
1087 /proc/mtrr file which may be used to manipulate your processor's
1088 MTRRs. Typically the X server should use this.
1090 This code has a reasonably generic interface so that similar
1091 control registers on other processors can be easily supported
1094 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1095 Registers (ARRs) which provide a similar functionality to MTRRs. For
1096 these, the ARRs are used to emulate the MTRRs.
1097 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1098 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1099 write-combining. All of these processors are supported by this code
1100 and it makes sense to say Y here if you have one of them.
1102 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1103 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1104 can lead to all sorts of problems, so it's good to say Y here.
1106 You can safely say Y even if your machine doesn't have MTRRs, you'll
1107 just add about 9 KB to your kernel.
1109 See <file:Documentation/mtrr.txt> for more information.
1111 config MTRR_SANITIZER
1113 prompt "MTRR cleanup support"
1116 Convert MTRR layout from continuous to discrete, so some X driver
1117 could add WB entries.
1119 Say N here if you see bootup problems (boot crash, boot hang,
1120 spontaneous reboots).
1122 Could be disabled with disable_mtrr_cleanup. Also mtrr_chunk_size
1123 could be used to send largest mtrr entry size for continuous block
1124 to hold holes (aka. UC entries)
1128 config MTRR_SANITIZER_ENABLE_DEFAULT
1129 int "MTRR cleanup enable value (0-1)"
1132 depends on MTRR_SANITIZER
1134 Enable mtrr cleanup default value
1136 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1137 int "MTRR cleanup spare reg num (0-7)"
1140 depends on MTRR_SANITIZER
1142 mtrr cleanup spare entries default, it can be changed via
1147 prompt "x86 PAT support"
1150 Use PAT attributes to setup page level cache control.
1152 PATs are the modern equivalents of MTRRs and are much more
1153 flexible than MTRRs.
1155 Say N here if you see bootup problems (boot crash, boot hang,
1156 spontaneous reboots) or a non-working video driver.
1162 prompt "EFI runtime service support"
1165 This enables the kernel to use EFI runtime services that are
1166 available (such as the EFI variable services).
1168 This option is only useful on systems that have EFI firmware.
1169 In addition, you should use the latest ELILO loader available
1170 at <http://elilo.sourceforge.net> in order to take advantage
1171 of EFI runtime services. However, even with this option, the
1172 resultant kernel should continue to boot on existing non-EFI
1177 prompt "Enable kernel irq balancing"
1178 depends on X86_32 && SMP && X86_IO_APIC
1180 The default yes will allow the kernel to do irq load balancing.
1181 Saying no will keep the kernel from doing irq load balancing.
1185 prompt "Enable seccomp to safely compute untrusted bytecode"
1188 This kernel feature is useful for number crunching applications
1189 that may need to compute untrusted bytecode during their
1190 execution. By using pipes or other transports made available to
1191 the process as file descriptors supporting the read/write
1192 syscalls, it's possible to isolate those applications in
1193 their own address space using seccomp. Once seccomp is
1194 enabled via /proc/<pid>/seccomp, it cannot be disabled
1195 and the task is only allowed to execute a few safe syscalls
1196 defined by each seccomp mode.
1198 If unsure, say Y. Only embedded should say N here.
1200 config CC_STACKPROTECTOR
1201 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1202 depends on X86_64 && EXPERIMENTAL && BROKEN
1204 This option turns on the -fstack-protector GCC feature. This
1205 feature puts, at the beginning of critical functions, a canary
1206 value on the stack just before the return address, and validates
1207 the value just before actually returning. Stack based buffer
1208 overflows (that need to overwrite this return address) now also
1209 overwrite the canary, which gets detected and the attack is then
1210 neutralized via a kernel panic.
1212 This feature requires gcc version 4.2 or above, or a distribution
1213 gcc with the feature backported. Older versions are automatically
1214 detected and for those versions, this configuration option is ignored.
1216 config CC_STACKPROTECTOR_ALL
1217 bool "Use stack-protector for all functions"
1218 depends on CC_STACKPROTECTOR
1220 Normally, GCC only inserts the canary value protection for
1221 functions that use large-ish on-stack buffers. By enabling
1222 this option, GCC will be asked to do this for ALL functions.
1224 source kernel/Kconfig.hz
1227 bool "kexec system call"
1228 depends on X86_BIOS_REBOOT
1230 kexec is a system call that implements the ability to shutdown your
1231 current kernel, and to start another kernel. It is like a reboot
1232 but it is independent of the system firmware. And like a reboot
1233 you can start any kernel with it, not just Linux.
1235 The name comes from the similarity to the exec system call.
1237 It is an ongoing process to be certain the hardware in a machine
1238 is properly shutdown, so do not be surprised if this code does not
1239 initially work for you. It may help to enable device hotplugging
1240 support. As of this writing the exact hardware interface is
1241 strongly in flux, so no good recommendation can be made.
1244 bool "kernel crash dumps (EXPERIMENTAL)"
1245 depends on EXPERIMENTAL
1246 depends on X86_64 || (X86_32 && HIGHMEM)
1248 Generate crash dump after being started by kexec.
1249 This should be normally only set in special crash dump kernels
1250 which are loaded in the main kernel with kexec-tools into
1251 a specially reserved region and then later executed after
1252 a crash by kdump/kexec. The crash dump kernel must be compiled
1253 to a memory address not used by the main kernel or BIOS using
1254 PHYSICAL_START, or it must be built as a relocatable image
1255 (CONFIG_RELOCATABLE=y).
1256 For more details see Documentation/kdump/kdump.txt
1258 config PHYSICAL_START
1259 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1260 default "0x1000000" if X86_NUMAQ
1261 default "0x200000" if X86_64
1264 This gives the physical address where the kernel is loaded.
1266 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1267 bzImage will decompress itself to above physical address and
1268 run from there. Otherwise, bzImage will run from the address where
1269 it has been loaded by the boot loader and will ignore above physical
1272 In normal kdump cases one does not have to set/change this option
1273 as now bzImage can be compiled as a completely relocatable image
1274 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1275 address. This option is mainly useful for the folks who don't want
1276 to use a bzImage for capturing the crash dump and want to use a
1277 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1278 to be specifically compiled to run from a specific memory area
1279 (normally a reserved region) and this option comes handy.
1281 So if you are using bzImage for capturing the crash dump, leave
1282 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1283 Otherwise if you plan to use vmlinux for capturing the crash dump
1284 change this value to start of the reserved region (Typically 16MB
1285 0x1000000). In other words, it can be set based on the "X" value as
1286 specified in the "crashkernel=YM@XM" command line boot parameter
1287 passed to the panic-ed kernel. Typically this parameter is set as
1288 crashkernel=64M@16M. Please take a look at
1289 Documentation/kdump/kdump.txt for more details about crash dumps.
1291 Usage of bzImage for capturing the crash dump is recommended as
1292 one does not have to build two kernels. Same kernel can be used
1293 as production kernel and capture kernel. Above option should have
1294 gone away after relocatable bzImage support is introduced. But it
1295 is present because there are users out there who continue to use
1296 vmlinux for dump capture. This option should go away down the
1299 Don't change this unless you know what you are doing.
1302 bool "Build a relocatable kernel (EXPERIMENTAL)"
1303 depends on EXPERIMENTAL
1305 This builds a kernel image that retains relocation information
1306 so it can be loaded someplace besides the default 1MB.
1307 The relocations tend to make the kernel binary about 10% larger,
1308 but are discarded at runtime.
1310 One use is for the kexec on panic case where the recovery kernel
1311 must live at a different physical address than the primary
1314 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1315 it has been loaded at and the compile time physical address
1316 (CONFIG_PHYSICAL_START) is ignored.
1318 config PHYSICAL_ALIGN
1320 prompt "Alignment value to which kernel should be aligned" if X86_32
1321 default "0x100000" if X86_32
1322 default "0x200000" if X86_64
1323 range 0x2000 0x400000
1325 This value puts the alignment restrictions on physical address
1326 where kernel is loaded and run from. Kernel is compiled for an
1327 address which meets above alignment restriction.
1329 If bootloader loads the kernel at a non-aligned address and
1330 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1331 address aligned to above value and run from there.
1333 If bootloader loads the kernel at a non-aligned address and
1334 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1335 load address and decompress itself to the address it has been
1336 compiled for and run from there. The address for which kernel is
1337 compiled already meets above alignment restrictions. Hence the
1338 end result is that kernel runs from a physical address meeting
1339 above alignment restrictions.
1341 Don't change this unless you know what you are doing.
1344 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1345 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1347 Say Y here to experiment with turning CPUs off and on, and to
1348 enable suspend on SMP systems. CPUs can be controlled through
1349 /sys/devices/system/cpu.
1350 Say N if you want to disable CPU hotplug and don't need to
1355 prompt "Compat VDSO support"
1356 depends on X86_32 || IA32_EMULATION
1358 Map the 32-bit VDSO to the predictable old-style address too.
1360 Say N here if you are running a sufficiently recent glibc
1361 version (2.3.3 or later), to remove the high-mapped
1362 VDSO mapping and to exclusively use the randomized VDSO.
1368 config ARCH_ENABLE_MEMORY_HOTPLUG
1370 depends on X86_64 || (X86_32 && HIGHMEM)
1372 config HAVE_ARCH_EARLY_PFN_TO_NID
1376 menu "Power management options"
1377 depends on !X86_VOYAGER
1379 config ARCH_HIBERNATION_HEADER
1381 depends on X86_64 && HIBERNATION
1383 source "kernel/power/Kconfig"
1385 source "drivers/acpi/Kconfig"
1390 depends on APM || APM_MODULE
1393 tristate "APM (Advanced Power Management) BIOS support"
1394 depends on X86_32 && PM_SLEEP && !X86_VISWS
1396 APM is a BIOS specification for saving power using several different
1397 techniques. This is mostly useful for battery powered laptops with
1398 APM compliant BIOSes. If you say Y here, the system time will be
1399 reset after a RESUME operation, the /proc/apm device will provide
1400 battery status information, and user-space programs will receive
1401 notification of APM "events" (e.g. battery status change).
1403 If you select "Y" here, you can disable actual use of the APM
1404 BIOS by passing the "apm=off" option to the kernel at boot time.
1406 Note that the APM support is almost completely disabled for
1407 machines with more than one CPU.
1409 In order to use APM, you will need supporting software. For location
1410 and more information, read <file:Documentation/power/pm.txt> and the
1411 Battery Powered Linux mini-HOWTO, available from
1412 <http://www.tldp.org/docs.html#howto>.
1414 This driver does not spin down disk drives (see the hdparm(8)
1415 manpage ("man 8 hdparm") for that), and it doesn't turn off
1416 VESA-compliant "green" monitors.
1418 This driver does not support the TI 4000M TravelMate and the ACER
1419 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1420 desktop machines also don't have compliant BIOSes, and this driver
1421 may cause those machines to panic during the boot phase.
1423 Generally, if you don't have a battery in your machine, there isn't
1424 much point in using this driver and you should say N. If you get
1425 random kernel OOPSes or reboots that don't seem to be related to
1426 anything, try disabling/enabling this option (or disabling/enabling
1429 Some other things you should try when experiencing seemingly random,
1432 1) make sure that you have enough swap space and that it is
1434 2) pass the "no-hlt" option to the kernel
1435 3) switch on floating point emulation in the kernel and pass
1436 the "no387" option to the kernel
1437 4) pass the "floppy=nodma" option to the kernel
1438 5) pass the "mem=4M" option to the kernel (thereby disabling
1439 all but the first 4 MB of RAM)
1440 6) make sure that the CPU is not over clocked.
1441 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1442 8) disable the cache from your BIOS settings
1443 9) install a fan for the video card or exchange video RAM
1444 10) install a better fan for the CPU
1445 11) exchange RAM chips
1446 12) exchange the motherboard.
1448 To compile this driver as a module, choose M here: the
1449 module will be called apm.
1453 config APM_IGNORE_USER_SUSPEND
1454 bool "Ignore USER SUSPEND"
1456 This option will ignore USER SUSPEND requests. On machines with a
1457 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1458 series notebooks, it is necessary to say Y because of a BIOS bug.
1460 config APM_DO_ENABLE
1461 bool "Enable PM at boot time"
1463 Enable APM features at boot time. From page 36 of the APM BIOS
1464 specification: "When disabled, the APM BIOS does not automatically
1465 power manage devices, enter the Standby State, enter the Suspend
1466 State, or take power saving steps in response to CPU Idle calls."
1467 This driver will make CPU Idle calls when Linux is idle (unless this
1468 feature is turned off -- see "Do CPU IDLE calls", below). This
1469 should always save battery power, but more complicated APM features
1470 will be dependent on your BIOS implementation. You may need to turn
1471 this option off if your computer hangs at boot time when using APM
1472 support, or if it beeps continuously instead of suspending. Turn
1473 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1474 T400CDT. This is off by default since most machines do fine without
1478 bool "Make CPU Idle calls when idle"
1480 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1481 On some machines, this can activate improved power savings, such as
1482 a slowed CPU clock rate, when the machine is idle. These idle calls
1483 are made after the idle loop has run for some length of time (e.g.,
1484 333 mS). On some machines, this will cause a hang at boot time or
1485 whenever the CPU becomes idle. (On machines with more than one CPU,
1486 this option does nothing.)
1488 config APM_DISPLAY_BLANK
1489 bool "Enable console blanking using APM"
1491 Enable console blanking using the APM. Some laptops can use this to
1492 turn off the LCD backlight when the screen blanker of the Linux
1493 virtual console blanks the screen. Note that this is only used by
1494 the virtual console screen blanker, and won't turn off the backlight
1495 when using the X Window system. This also doesn't have anything to
1496 do with your VESA-compliant power-saving monitor. Further, this
1497 option doesn't work for all laptops -- it might not turn off your
1498 backlight at all, or it might print a lot of errors to the console,
1499 especially if you are using gpm.
1501 config APM_ALLOW_INTS
1502 bool "Allow interrupts during APM BIOS calls"
1504 Normally we disable external interrupts while we are making calls to
1505 the APM BIOS as a measure to lessen the effects of a badly behaving
1506 BIOS implementation. The BIOS should reenable interrupts if it
1507 needs to. Unfortunately, some BIOSes do not -- especially those in
1508 many of the newer IBM Thinkpads. If you experience hangs when you
1509 suspend, try setting this to Y. Otherwise, say N.
1511 config APM_REAL_MODE_POWER_OFF
1512 bool "Use real mode APM BIOS call to power off"
1514 Use real mode APM BIOS calls to switch off the computer. This is
1515 a work-around for a number of buggy BIOSes. Switch this option on if
1516 your computer crashes instead of powering off properly.
1520 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1522 source "drivers/cpuidle/Kconfig"
1527 menu "Bus options (PCI etc.)"
1532 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1534 Find out whether you have a PCI motherboard. PCI is the name of a
1535 bus system, i.e. the way the CPU talks to the other stuff inside
1536 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1537 VESA. If you have PCI, say Y, otherwise N.
1540 prompt "PCI access mode"
1541 depends on X86_32 && PCI && !X86_VISWS
1544 On PCI systems, the BIOS can be used to detect the PCI devices and
1545 determine their configuration. However, some old PCI motherboards
1546 have BIOS bugs and may crash if this is done. Also, some embedded
1547 PCI-based systems don't have any BIOS at all. Linux can also try to
1548 detect the PCI hardware directly without using the BIOS.
1550 With this option, you can specify how Linux should detect the
1551 PCI devices. If you choose "BIOS", the BIOS will be used,
1552 if you choose "Direct", the BIOS won't be used, and if you
1553 choose "MMConfig", then PCI Express MMCONFIG will be used.
1554 If you choose "Any", the kernel will try MMCONFIG, then the
1555 direct access method and falls back to the BIOS if that doesn't
1556 work. If unsure, go with the default, which is "Any".
1561 config PCI_GOMMCONFIG
1578 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1580 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1583 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
1587 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1591 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1598 bool "Support mmconfig PCI config space access"
1599 depends on X86_64 && PCI && ACPI
1602 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1603 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1605 DMA remapping (DMAR) devices support enables independent address
1606 translations for Direct Memory Access (DMA) from devices.
1607 These DMA remapping devices are reported via ACPI tables
1608 and include PCI device scope covered by these DMA
1613 prompt "Support for Graphics workaround"
1616 Current Graphics drivers tend to use physical address
1617 for DMA and avoid using DMA APIs. Setting this config
1618 option permits the IOMMU driver to set a unity map for
1619 all the OS-visible memory. Hence the driver can continue
1620 to use physical addresses for DMA.
1622 config DMAR_FLOPPY_WA
1626 Floppy disk drivers are know to bypass DMA API calls
1627 thereby failing to work when IOMMU is enabled. This
1628 workaround will setup a 1:1 mapping for the first
1629 16M to make floppy (an ISA device) work.
1631 source "drivers/pci/pcie/Kconfig"
1633 source "drivers/pci/Kconfig"
1635 # x86_64 have no ISA slots, but do have ISA-style DMA.
1643 depends on !(X86_VOYAGER || X86_VISWS)
1645 Find out whether you have ISA slots on your motherboard. ISA is the
1646 name of a bus system, i.e. the way the CPU talks to the other stuff
1647 inside your box. Other bus systems are PCI, EISA, MicroChannel
1648 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1649 newer boards don't support it. If you have ISA, say Y, otherwise N.
1655 The Extended Industry Standard Architecture (EISA) bus was
1656 developed as an open alternative to the IBM MicroChannel bus.
1658 The EISA bus provided some of the features of the IBM MicroChannel
1659 bus while maintaining backward compatibility with cards made for
1660 the older ISA bus. The EISA bus saw limited use between 1988 and
1661 1995 when it was made obsolete by the PCI bus.
1663 Say Y here if you are building a kernel for an EISA-based machine.
1667 source "drivers/eisa/Kconfig"
1670 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1671 default y if X86_VOYAGER
1673 MicroChannel Architecture is found in some IBM PS/2 machines and
1674 laptops. It is a bus system similar to PCI or ISA. See
1675 <file:Documentation/mca.txt> (and especially the web page given
1676 there) before attempting to build an MCA bus kernel.
1678 source "drivers/mca/Kconfig"
1681 tristate "NatSemi SCx200 support"
1682 depends on !X86_VOYAGER
1684 This provides basic support for National Semiconductor's
1685 (now AMD's) Geode processors. The driver probes for the
1686 PCI-IDs of several on-chip devices, so its a good dependency
1687 for other scx200_* drivers.
1689 If compiled as a module, the driver is named scx200.
1691 config SCx200HR_TIMER
1692 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1693 depends on SCx200 && GENERIC_TIME
1696 This driver provides a clocksource built upon the on-chip
1697 27MHz high-resolution timer. Its also a workaround for
1698 NSC Geode SC-1100's buggy TSC, which loses time when the
1699 processor goes idle (as is done by the scheduler). The
1700 other workaround is idle=poll boot option.
1702 config GEODE_MFGPT_TIMER
1704 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1705 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1707 This driver provides a clock event source based on the MFGPT
1708 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1709 MFGPTs have a better resolution and max interval than the
1710 generic PIT, and are suitable for use as high-res timers.
1713 bool "One Laptop Per Child support"
1716 Add support for detecting the unique features of the OLPC
1723 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1725 source "drivers/pcmcia/Kconfig"
1727 source "drivers/pci/hotplug/Kconfig"
1732 menu "Executable file formats / Emulations"
1734 source "fs/Kconfig.binfmt"
1736 config IA32_EMULATION
1737 bool "IA32 Emulation"
1739 select COMPAT_BINFMT_ELF
1741 Include code to run 32-bit programs under a 64-bit kernel. You should
1742 likely turn this on, unless you're 100% sure that you don't have any
1743 32-bit programs left.
1746 tristate "IA32 a.out support"
1747 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1749 Support old a.out binaries in the 32bit emulation.
1753 depends on IA32_EMULATION
1755 config COMPAT_FOR_U64_ALIGNMENT
1759 config SYSVIPC_COMPAT
1761 depends on X86_64 && COMPAT && SYSVIPC
1766 source "net/Kconfig"
1768 source "drivers/Kconfig"
1770 source "drivers/firmware/Kconfig"
1774 source "arch/x86/Kconfig.debug"
1776 source "security/Kconfig"
1778 source "crypto/Kconfig"
1780 source "arch/x86/kvm/Kconfig"
1782 source "lib/Kconfig"
projects / deliverable / linux.git / blob