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 if !X86_RDC321X
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_EFFICIENT_UNALIGNED_ACCESS
36 default "arch/x86/configs/i386_defconfig" if X86_32
37 default "arch/x86/configs/x86_64_defconfig" if X86_64
40 config GENERIC_LOCKBREAK
46 config GENERIC_CMOS_UPDATE
49 config CLOCKSOURCE_WATCHDOG
52 config GENERIC_CLOCKEVENTS
55 config GENERIC_CLOCKEVENTS_BROADCAST
57 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
59 config LOCKDEP_SUPPORT
62 config STACKTRACE_SUPPORT
65 config HAVE_LATENCYTOP_SUPPORT
68 config FAST_CMPXCHG_LOCAL
81 config GENERIC_ISA_DMA
91 config GENERIC_HWEIGHT
97 config ARCH_MAY_HAVE_PC_FDC
100 config RWSEM_GENERIC_SPINLOCK
103 config RWSEM_XCHGADD_ALGORITHM
106 config ARCH_HAS_ILOG2_U32
109 config ARCH_HAS_ILOG2_U64
112 config ARCH_HAS_CPU_IDLE_WAIT
115 config GENERIC_CALIBRATE_DELAY
118 config GENERIC_TIME_VSYSCALL
122 config ARCH_HAS_CPU_RELAX
125 config ARCH_HAS_CACHE_LINE_SIZE
128 config HAVE_SETUP_PER_CPU_AREA
129 def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER)
131 config HAVE_CPUMASK_OF_CPU_MAP
134 config ARCH_HIBERNATION_POSSIBLE
136 depends on !SMP || !X86_VOYAGER
138 config ARCH_SUSPEND_POSSIBLE
140 depends on !X86_VOYAGER
146 config ARCH_POPULATES_NODE_MAP
153 config ARCH_SUPPORTS_AOUT
156 config ARCH_SUPPORTS_OPTIMIZED_INLINING
159 # Use the generic interrupt handling code in kernel/irq/:
160 config GENERIC_HARDIRQS
164 config GENERIC_IRQ_PROBE
168 config GENERIC_PENDING_IRQ
170 depends on GENERIC_HARDIRQS && SMP
175 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
176 select USE_GENERIC_SMP_HELPERS
181 depends on X86_32 && SMP
185 depends on X86_64 && SMP
190 depends on (X86_32 && !X86_VOYAGER) || X86_64
193 config X86_BIOS_REBOOT
195 depends on !X86_VOYAGER
198 config X86_TRAMPOLINE
200 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
205 source "init/Kconfig"
207 menu "Processor type and features"
209 source "kernel/time/Kconfig"
212 bool "Symmetric multi-processing support"
214 This enables support for systems with more than one CPU. If you have
215 a system with only one CPU, like most personal computers, say N. If
216 you have a system with more than one CPU, say Y.
218 If you say N here, the kernel will run on single and multiprocessor
219 machines, but will use only one CPU of a multiprocessor machine. If
220 you say Y here, the kernel will run on many, but not all,
221 singleprocessor machines. On a singleprocessor machine, the kernel
222 will run faster if you say N here.
224 Note that if you say Y here and choose architecture "586" or
225 "Pentium" under "Processor family", the kernel will not work on 486
226 architectures. Similarly, multiprocessor kernels for the "PPro"
227 architecture may not work on all Pentium based boards.
229 People using multiprocessor machines who say Y here should also say
230 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
231 Management" code will be disabled if you say Y here.
233 See also <file:Documentation/i386/IO-APIC.txt>,
234 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
235 <http://www.tldp.org/docs.html#howto>.
237 If you don't know what to do here, say N.
239 config X86_FIND_SMP_CONFIG
241 depends on X86_MPPARSE || X86_VOYAGER
246 bool "Enable MPS table"
247 depends on X86_LOCAL_APIC
249 For old smp systems that do not have proper acpi support. Newer systems
250 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
256 depends on X86_LOCAL_APIC
260 prompt "Subarchitecture Type"
266 Choose this option if your computer is a standard PC or compatible.
272 Select this for an AMD Elan processor.
274 Do not use this option for K6/Athlon/Opteron processors!
276 If unsure, choose "PC-compatible" instead.
280 depends on X86_32 && (SMP || BROKEN) && !PCI
282 Voyager is an MCA-based 32-way capable SMP architecture proprietary
283 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
287 If you do not specifically know you have a Voyager based machine,
288 say N here, otherwise the kernel you build will not be bootable.
290 config X86_GENERICARCH
291 bool "Generic architecture"
294 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
295 subarchitectures. It is intended for a generic binary kernel.
296 if you select them all, kernel will probe it one by one. and will
302 bool "NUMAQ (IBM/Sequent)"
303 depends on SMP && X86_32 && PCI && X86_MPPARSE
306 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
307 NUMA multiquad box. This changes the way that processors are
308 bootstrapped, and uses Clustered Logical APIC addressing mode instead
309 of Flat Logical. You will need a new lynxer.elf file to flash your
310 firmware with - send email to <Martin.Bligh@us.ibm.com>.
313 bool "Summit/EXA (IBM x440)"
314 depends on X86_32 && SMP
316 This option is needed for IBM systems that use the Summit/EXA chipset.
317 In particular, it is needed for the x440.
320 bool "Support for Unisys ES7000 IA32 series"
321 depends on X86_32 && SMP
323 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
324 supposed to run on an IA32-based Unisys ES7000 system.
327 bool "Support for big SMP systems with more than 8 CPUs"
328 depends on X86_32 && SMP
330 This option is needed for the systems that have more than 8 CPUs
331 and if the system is not of any sub-arch type above.
336 bool "RDC R-321x SoC"
339 select X86_REBOOTFIXUPS
345 This option is needed for RDC R-321x system-on-chip, also known
347 If you don't have one of these chips, you should say N here.
350 bool "Support for ScaleMP vSMP"
352 depends on X86_64 && PCI
354 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
355 supposed to run on these EM64T-based machines. Only choose this option
356 if you have one of these machines.
361 bool "SGI 320/540 (Visual Workstation)"
362 depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT
364 The SGI Visual Workstation series is an IA32-based workstation
365 based on SGI systems chips with some legacy PC hardware attached.
367 Say Y here to create a kernel to run on the SGI 320 or 540.
369 A kernel compiled for the Visual Workstation will run on general
370 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
372 config SCHED_NO_NO_OMIT_FRAME_POINTER
374 prompt "Single-depth WCHAN output"
377 Calculate simpler /proc/<PID>/wchan values. If this option
378 is disabled then wchan values will recurse back to the
379 caller function. This provides more accurate wchan values,
380 at the expense of slightly more scheduling overhead.
382 If in doubt, say "Y".
384 menuconfig PARAVIRT_GUEST
385 bool "Paravirtualized guest support"
387 Say Y here to get to see options related to running Linux under
388 various hypervisors. This option alone does not add any kernel code.
390 If you say N, all options in this submenu will be skipped and disabled.
394 source "arch/x86/xen/Kconfig"
397 bool "VMI Guest support"
400 depends on !X86_VOYAGER
402 VMI provides a paravirtualized interface to the VMware ESX server
403 (it could be used by other hypervisors in theory too, but is not
404 at the moment), by linking the kernel to a GPL-ed ROM module
405 provided by the hypervisor.
408 bool "KVM paravirtualized clock"
410 select PARAVIRT_CLOCK
411 depends on !X86_VOYAGER
413 Turning on this option will allow you to run a paravirtualized clock
414 when running over the KVM hypervisor. Instead of relying on a PIT
415 (or probably other) emulation by the underlying device model, the host
416 provides the guest with timing infrastructure such as time of day, and
420 bool "KVM Guest support"
422 depends on !X86_VOYAGER
424 This option enables various optimizations for running under the KVM
427 source "arch/x86/lguest/Kconfig"
430 bool "Enable paravirtualization code"
431 depends on !X86_VOYAGER
433 This changes the kernel so it can modify itself when it is run
434 under a hypervisor, potentially improving performance significantly
435 over full virtualization. However, when run without a hypervisor
436 the kernel is theoretically slower and slightly larger.
438 config PARAVIRT_CLOCK
444 config PARAVIRT_DEBUG
445 bool "paravirt-ops debugging"
446 depends on PARAVIRT && DEBUG_KERNEL
448 Enable to debug paravirt_ops internals. Specifically, BUG if
449 a paravirt_op is missing when it is called.
454 This option adds a kernel parameter 'memtest', which allows memtest
456 memtest=0, mean disabled; -- default
457 memtest=1, mean do 1 test pattern;
459 memtest=4, mean do 4 test patterns.
460 If you are unsure how to answer this question, answer N.
462 config X86_SUMMIT_NUMA
464 depends on X86_32 && NUMA && X86_GENERICARCH
466 config X86_CYCLONE_TIMER
468 depends on X86_GENERICARCH
470 config ES7000_CLUSTERED_APIC
472 depends on SMP && X86_ES7000 && MPENTIUMIII
474 source "arch/x86/Kconfig.cpu"
478 prompt "HPET Timer Support" if X86_32
480 Use the IA-PC HPET (High Precision Event Timer) to manage
481 time in preference to the PIT and RTC, if a HPET is
483 HPET is the next generation timer replacing legacy 8254s.
484 The HPET provides a stable time base on SMP
485 systems, unlike the TSC, but it is more expensive to access,
486 as it is off-chip. You can find the HPET spec at
487 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
489 You can safely choose Y here. However, HPET will only be
490 activated if the platform and the BIOS support this feature.
491 Otherwise the 8254 will be used for timing services.
493 Choose N to continue using the legacy 8254 timer.
495 config HPET_EMULATE_RTC
497 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
499 # Mark as embedded because too many people got it wrong.
500 # The code disables itself when not needed.
503 bool "Enable DMI scanning" if EMBEDDED
505 Enabled scanning of DMI to identify machine quirks. Say Y
506 here unless you have verified that your setup is not
507 affected by entries in the DMI blacklist. Required by PNP
511 bool "GART IOMMU support" if EMBEDDED
515 depends on X86_64 && PCI
517 Support for full DMA access of devices with 32bit memory access only
518 on systems with more than 3GB. This is usually needed for USB,
519 sound, many IDE/SATA chipsets and some other devices.
520 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
521 based hardware IOMMU and a software bounce buffer based IOMMU used
522 on Intel systems and as fallback.
523 The code is only active when needed (enough memory and limited
524 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
528 bool "IBM Calgary IOMMU support"
530 depends on X86_64 && PCI && EXPERIMENTAL
532 Support for hardware IOMMUs in IBM's xSeries x366 and x460
533 systems. Needed to run systems with more than 3GB of memory
534 properly with 32-bit PCI devices that do not support DAC
535 (Double Address Cycle). Calgary also supports bus level
536 isolation, where all DMAs pass through the IOMMU. This
537 prevents them from going anywhere except their intended
538 destination. This catches hard-to-find kernel bugs and
539 mis-behaving drivers and devices that do not use the DMA-API
540 properly to set up their DMA buffers. The IOMMU can be
541 turned off at boot time with the iommu=off parameter.
542 Normally the kernel will make the right choice by itself.
545 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
547 prompt "Should Calgary be enabled by default?"
548 depends on CALGARY_IOMMU
550 Should Calgary be enabled by default? if you choose 'y', Calgary
551 will be used (if it exists). If you choose 'n', Calgary will not be
552 used even if it exists. If you choose 'n' and would like to use
553 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
557 bool "AMD IOMMU support"
559 depends on X86_64 && PCI && ACPI
561 With this option you can enable support for AMD IOMMU hardware in
562 your system. An IOMMU is a hardware component which provides
563 remapping of DMA memory accesses from devices. With an AMD IOMMU you
564 can isolate the the DMA memory of different devices and protect the
565 system from misbehaving device drivers or hardware.
567 You can find out if your system has an AMD IOMMU if you look into
568 your BIOS for an option to enable it or if you have an IVRS ACPI
571 # need this always selected by IOMMU for the VIA workaround
575 Support for software bounce buffers used on x86-64 systems
576 which don't have a hardware IOMMU (e.g. the current generation
577 of Intel's x86-64 CPUs). Using this PCI devices which can only
578 access 32-bits of memory can be used on systems with more than
579 3 GB of memory. If unsure, say Y.
582 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
584 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
585 depends on X86_64 && SMP
588 Configure maximum number of CPUS and NUMA Nodes for this architecture.
599 int "Maximum number of CPUs (2-4096)"
602 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
605 This allows you to specify the maximum number of CPUs which this
606 kernel will support. The maximum supported value is 4096 and the
607 minimum value which makes sense is 2.
609 This is purely to save memory - each supported CPU adds
610 approximately eight kilobytes to the kernel image.
614 bool "SMT (Hyperthreading) scheduler support"
617 SMT scheduler support improves the CPU scheduler's decision making
618 when dealing with Intel Pentium 4 chips with HyperThreading at a
619 cost of slightly increased overhead in some places. If unsure say
624 prompt "Multi-core scheduler support"
627 Multi-core scheduler support improves the CPU scheduler's decision
628 making when dealing with multi-core CPU chips at a cost of slightly
629 increased overhead in some places. If unsure say N here.
631 source "kernel/Kconfig.preempt"
634 bool "Local APIC support on uniprocessors"
635 depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH)
637 A local APIC (Advanced Programmable Interrupt Controller) is an
638 integrated interrupt controller in the CPU. If you have a single-CPU
639 system which has a processor with a local APIC, you can say Y here to
640 enable and use it. If you say Y here even though your machine doesn't
641 have a local APIC, then the kernel will still run with no slowdown at
642 all. The local APIC supports CPU-generated self-interrupts (timer,
643 performance counters), and the NMI watchdog which detects hard
647 bool "IO-APIC support on uniprocessors"
648 depends on X86_UP_APIC
650 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
651 SMP-capable replacement for PC-style interrupt controllers. Most
652 SMP systems and many recent uniprocessor systems have one.
654 If you have a single-CPU system with an IO-APIC, you can say Y here
655 to use it. If you say Y here even though your machine doesn't have
656 an IO-APIC, then the kernel will still run with no slowdown at all.
658 config X86_LOCAL_APIC
660 depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
664 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
666 config X86_VISWS_APIC
668 depends on X86_32 && X86_VISWS
671 bool "Machine Check Exception"
672 depends on !X86_VOYAGER
674 Machine Check Exception support allows the processor to notify the
675 kernel if it detects a problem (e.g. overheating, component failure).
676 The action the kernel takes depends on the severity of the problem,
677 ranging from a warning message on the console, to halting the machine.
678 Your processor must be a Pentium or newer to support this - check the
679 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
680 have a design flaw which leads to false MCE events - hence MCE is
681 disabled on all P5 processors, unless explicitly enabled with "mce"
682 as a boot argument. Similarly, if MCE is built in and creates a
683 problem on some new non-standard machine, you can boot with "nomce"
684 to disable it. MCE support simply ignores non-MCE processors like
685 the 386 and 486, so nearly everyone can say Y here.
689 prompt "Intel MCE features"
690 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
692 Additional support for intel specific MCE features such as
697 prompt "AMD MCE features"
698 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
700 Additional support for AMD specific MCE features such as
701 the DRAM Error Threshold.
703 config X86_MCE_NONFATAL
704 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
705 depends on X86_32 && X86_MCE
707 Enabling this feature starts a timer that triggers every 5 seconds which
708 will look at the machine check registers to see if anything happened.
709 Non-fatal problems automatically get corrected (but still logged).
710 Disable this if you don't want to see these messages.
711 Seeing the messages this option prints out may be indicative of dying
712 or out-of-spec (ie, overclocked) hardware.
713 This option only does something on certain CPUs.
714 (AMD Athlon/Duron and Intel Pentium 4)
716 config X86_MCE_P4THERMAL
717 bool "check for P4 thermal throttling interrupt."
718 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
720 Enabling this feature will cause a message to be printed when the P4
721 enters thermal throttling.
724 bool "Enable VM86 support" if EMBEDDED
728 This option is required by programs like DOSEMU to run 16-bit legacy
729 code on X86 processors. It also may be needed by software like
730 XFree86 to initialize some video cards via BIOS. Disabling this
731 option saves about 6k.
734 tristate "Toshiba Laptop support"
737 This adds a driver to safely access the System Management Mode of
738 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
739 not work on models with a Phoenix BIOS. The System Management Mode
740 is used to set the BIOS and power saving options on Toshiba portables.
742 For information on utilities to make use of this driver see the
743 Toshiba Linux utilities web site at:
744 <http://www.buzzard.org.uk/toshiba/>.
746 Say Y if you intend to run this kernel on a Toshiba portable.
750 tristate "Dell laptop support"
752 This adds a driver to safely access the System Management Mode
753 of the CPU on the Dell Inspiron 8000. The System Management Mode
754 is used to read cpu temperature and cooling fan status and to
755 control the fans on the I8K portables.
757 This driver has been tested only on the Inspiron 8000 but it may
758 also work with other Dell laptops. You can force loading on other
759 models by passing the parameter `force=1' to the module. Use at
762 For information on utilities to make use of this driver see the
763 I8K Linux utilities web site at:
764 <http://people.debian.org/~dz/i8k/>
766 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
769 config X86_REBOOTFIXUPS
771 prompt "Enable X86 board specific fixups for reboot"
772 depends on X86_32 && X86
774 This enables chipset and/or board specific fixups to be done
775 in order to get reboot to work correctly. This is only needed on
776 some combinations of hardware and BIOS. The symptom, for which
777 this config is intended, is when reboot ends with a stalled/hung
780 Currently, the only fixup is for the Geode machines using
781 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
783 Say Y if you want to enable the fixup. Currently, it's safe to
784 enable this option even if you don't need it.
788 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
791 If you say Y here, you will be able to update the microcode on
792 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
793 Pentium III, Pentium 4, Xeon etc. You will obviously need the
794 actual microcode binary data itself which is not shipped with the
797 For latest news and information on obtaining all the required
798 ingredients for this driver, check:
799 <http://www.urbanmyth.org/microcode/>.
801 To compile this driver as a module, choose M here: the
802 module will be called microcode.
804 config MICROCODE_OLD_INTERFACE
809 tristate "/dev/cpu/*/msr - Model-specific register support"
811 This device gives privileged processes access to the x86
812 Model-Specific Registers (MSRs). It is a character device with
813 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
814 MSR accesses are directed to a specific CPU on multi-processor
818 tristate "/dev/cpu/*/cpuid - CPU information support"
820 This device gives processes access to the x86 CPUID instruction to
821 be executed on a specific processor. It is a character device
822 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
826 prompt "High Memory Support"
827 default HIGHMEM4G if !X86_NUMAQ
828 default HIGHMEM64G if X86_NUMAQ
833 depends on !X86_NUMAQ
835 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
836 However, the address space of 32-bit x86 processors is only 4
837 Gigabytes large. That means that, if you have a large amount of
838 physical memory, not all of it can be "permanently mapped" by the
839 kernel. The physical memory that's not permanently mapped is called
842 If you are compiling a kernel which will never run on a machine with
843 more than 1 Gigabyte total physical RAM, answer "off" here (default
844 choice and suitable for most users). This will result in a "3GB/1GB"
845 split: 3GB are mapped so that each process sees a 3GB virtual memory
846 space and the remaining part of the 4GB virtual memory space is used
847 by the kernel to permanently map as much physical memory as
850 If the machine has between 1 and 4 Gigabytes physical RAM, then
853 If more than 4 Gigabytes is used then answer "64GB" here. This
854 selection turns Intel PAE (Physical Address Extension) mode on.
855 PAE implements 3-level paging on IA32 processors. PAE is fully
856 supported by Linux, PAE mode is implemented on all recent Intel
857 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
858 then the kernel will not boot on CPUs that don't support PAE!
860 The actual amount of total physical memory will either be
861 auto detected or can be forced by using a kernel command line option
862 such as "mem=256M". (Try "man bootparam" or see the documentation of
863 your boot loader (lilo or loadlin) about how to pass options to the
864 kernel at boot time.)
866 If unsure, say "off".
870 depends on !X86_NUMAQ
872 Select this if you have a 32-bit processor and between 1 and 4
873 gigabytes of physical RAM.
877 depends on !M386 && !M486
880 Select this if you have a 32-bit processor and more than 4
881 gigabytes of physical RAM.
886 depends on EXPERIMENTAL
887 prompt "Memory split" if EMBEDDED
891 Select the desired split between kernel and user memory.
893 If the address range available to the kernel is less than the
894 physical memory installed, the remaining memory will be available
895 as "high memory". Accessing high memory is a little more costly
896 than low memory, as it needs to be mapped into the kernel first.
897 Note that increasing the kernel address space limits the range
898 available to user programs, making the address space there
899 tighter. Selecting anything other than the default 3G/1G split
900 will also likely make your kernel incompatible with binary-only
903 If you are not absolutely sure what you are doing, leave this
907 bool "3G/1G user/kernel split"
908 config VMSPLIT_3G_OPT
910 bool "3G/1G user/kernel split (for full 1G low memory)"
912 bool "2G/2G user/kernel split"
913 config VMSPLIT_2G_OPT
915 bool "2G/2G user/kernel split (for full 2G low memory)"
917 bool "1G/3G user/kernel split"
922 default 0xB0000000 if VMSPLIT_3G_OPT
923 default 0x80000000 if VMSPLIT_2G
924 default 0x78000000 if VMSPLIT_2G_OPT
925 default 0x40000000 if VMSPLIT_1G
931 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
935 prompt "PAE (Physical Address Extension) Support"
936 depends on X86_32 && !HIGHMEM4G
937 select RESOURCES_64BIT
939 PAE is required for NX support, and furthermore enables
940 larger swapspace support for non-overcommit purposes. It
941 has the cost of more pagetable lookup overhead, and also
942 consumes more pagetable space per process.
944 # Common NUMA Features
946 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
948 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
950 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
952 Enable NUMA (Non Uniform Memory Access) support.
953 The kernel will try to allocate memory used by a CPU on the
954 local memory controller of the CPU and add some more
955 NUMA awareness to the kernel.
957 For i386 this is currently highly experimental and should be only
958 used for kernel development. It might also cause boot failures.
959 For x86_64 this is recommended on all multiprocessor Opteron systems.
960 If the system is EM64T, you should say N unless your system is
963 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
964 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
968 prompt "Old style AMD Opteron NUMA detection"
969 depends on X86_64 && NUMA && PCI
971 Enable K8 NUMA node topology detection. You should say Y here if
972 you have a multi processor AMD K8 system. This uses an old
973 method to read the NUMA configuration directly from the builtin
974 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
975 instead, which also takes priority if both are compiled in.
977 config X86_64_ACPI_NUMA
979 prompt "ACPI NUMA detection"
980 depends on X86_64 && NUMA && ACPI && PCI
983 Enable ACPI SRAT based node topology detection.
985 # Some NUMA nodes have memory ranges that span
986 # other nodes. Even though a pfn is valid and
987 # between a node's start and end pfns, it may not
988 # reside on that node. See memmap_init_zone()
990 config NODES_SPAN_OTHER_NODES
992 depends on X86_64_ACPI_NUMA
995 bool "NUMA emulation"
996 depends on X86_64 && NUMA
998 Enable NUMA emulation. A flat machine will be split
999 into virtual nodes when booted with "numa=fake=N", where N is the
1000 number of nodes. This is only useful for debugging.
1011 int "Maximum NUMA Nodes (as a power of 2)"
1013 default "6" if X86_64
1014 default "4" if X86_NUMAQ
1016 depends on NEED_MULTIPLE_NODES
1018 Specify the maximum number of NUMA Nodes available on the target
1019 system. Increases memory reserved to accomodate various tables.
1022 config HAVE_ARCH_BOOTMEM_NODE
1024 depends on X86_32 && NUMA
1026 config ARCH_HAVE_MEMORY_PRESENT
1028 depends on X86_32 && DISCONTIGMEM
1030 config NEED_NODE_MEMMAP_SIZE
1032 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1034 config HAVE_ARCH_ALLOC_REMAP
1036 depends on X86_32 && NUMA
1038 config ARCH_FLATMEM_ENABLE
1040 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
1042 config ARCH_DISCONTIGMEM_ENABLE
1044 depends on NUMA && X86_32
1046 config ARCH_DISCONTIGMEM_DEFAULT
1048 depends on NUMA && X86_32
1050 config ARCH_SPARSEMEM_DEFAULT
1054 config ARCH_SPARSEMEM_ENABLE
1056 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1057 select SPARSEMEM_STATIC if X86_32
1058 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1060 config ARCH_SELECT_MEMORY_MODEL
1062 depends on ARCH_SPARSEMEM_ENABLE
1064 config ARCH_MEMORY_PROBE
1066 depends on MEMORY_HOTPLUG
1071 bool "Allocate 3rd-level pagetables from highmem"
1072 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1074 The VM uses one page table entry for each page of physical memory.
1075 For systems with a lot of RAM, this can be wasteful of precious
1076 low memory. Setting this option will put user-space page table
1077 entries in high memory.
1079 config MATH_EMULATION
1081 prompt "Math emulation" if X86_32
1083 Linux can emulate a math coprocessor (used for floating point
1084 operations) if you don't have one. 486DX and Pentium processors have
1085 a math coprocessor built in, 486SX and 386 do not, unless you added
1086 a 487DX or 387, respectively. (The messages during boot time can
1087 give you some hints here ["man dmesg"].) Everyone needs either a
1088 coprocessor or this emulation.
1090 If you don't have a math coprocessor, you need to say Y here; if you
1091 say Y here even though you have a coprocessor, the coprocessor will
1092 be used nevertheless. (This behavior can be changed with the kernel
1093 command line option "no387", which comes handy if your coprocessor
1094 is broken. Try "man bootparam" or see the documentation of your boot
1095 loader (lilo or loadlin) about how to pass options to the kernel at
1096 boot time.) This means that it is a good idea to say Y here if you
1097 intend to use this kernel on different machines.
1099 More information about the internals of the Linux math coprocessor
1100 emulation can be found in <file:arch/x86/math-emu/README>.
1102 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1103 kernel, it won't hurt.
1106 bool "MTRR (Memory Type Range Register) support"
1108 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1109 the Memory Type Range Registers (MTRRs) may be used to control
1110 processor access to memory ranges. This is most useful if you have
1111 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1112 allows bus write transfers to be combined into a larger transfer
1113 before bursting over the PCI/AGP bus. This can increase performance
1114 of image write operations 2.5 times or more. Saying Y here creates a
1115 /proc/mtrr file which may be used to manipulate your processor's
1116 MTRRs. Typically the X server should use this.
1118 This code has a reasonably generic interface so that similar
1119 control registers on other processors can be easily supported
1122 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1123 Registers (ARRs) which provide a similar functionality to MTRRs. For
1124 these, the ARRs are used to emulate the MTRRs.
1125 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1126 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1127 write-combining. All of these processors are supported by this code
1128 and it makes sense to say Y here if you have one of them.
1130 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1131 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1132 can lead to all sorts of problems, so it's good to say Y here.
1134 You can safely say Y even if your machine doesn't have MTRRs, you'll
1135 just add about 9 KB to your kernel.
1137 See <file:Documentation/mtrr.txt> for more information.
1139 config MTRR_SANITIZER
1141 prompt "MTRR cleanup support"
1144 Convert MTRR layout from continuous to discrete, so X drivers can
1145 add writeback entries.
1147 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1148 The largest mtrr entry size for a continous block can be set with
1153 config MTRR_SANITIZER_ENABLE_DEFAULT
1154 int "MTRR cleanup enable value (0-1)"
1157 depends on MTRR_SANITIZER
1159 Enable mtrr cleanup default value
1161 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1162 int "MTRR cleanup spare reg num (0-7)"
1165 depends on MTRR_SANITIZER
1167 mtrr cleanup spare entries default, it can be changed via
1168 mtrr_spare_reg_nr=N on the kernel command line.
1172 prompt "x86 PAT support"
1175 Use PAT attributes to setup page level cache control.
1177 PATs are the modern equivalents of MTRRs and are much more
1178 flexible than MTRRs.
1180 Say N here if you see bootup problems (boot crash, boot hang,
1181 spontaneous reboots) or a non-working video driver.
1187 prompt "EFI runtime service support"
1190 This enables the kernel to use EFI runtime services that are
1191 available (such as the EFI variable services).
1193 This option is only useful on systems that have EFI firmware.
1194 In addition, you should use the latest ELILO loader available
1195 at <http://elilo.sourceforge.net> in order to take advantage
1196 of EFI runtime services. However, even with this option, the
1197 resultant kernel should continue to boot on existing non-EFI
1202 prompt "Enable kernel irq balancing"
1203 depends on X86_32 && SMP && X86_IO_APIC
1205 The default yes will allow the kernel to do irq load balancing.
1206 Saying no will keep the kernel from doing irq load balancing.
1210 prompt "Enable seccomp to safely compute untrusted bytecode"
1213 This kernel feature is useful for number crunching applications
1214 that may need to compute untrusted bytecode during their
1215 execution. By using pipes or other transports made available to
1216 the process as file descriptors supporting the read/write
1217 syscalls, it's possible to isolate those applications in
1218 their own address space using seccomp. Once seccomp is
1219 enabled via /proc/<pid>/seccomp, it cannot be disabled
1220 and the task is only allowed to execute a few safe syscalls
1221 defined by each seccomp mode.
1223 If unsure, say Y. Only embedded should say N here.
1225 config CC_STACKPROTECTOR
1226 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1227 depends on X86_64 && EXPERIMENTAL && BROKEN
1229 This option turns on the -fstack-protector GCC feature. This
1230 feature puts, at the beginning of critical functions, a canary
1231 value on the stack just before the return address, and validates
1232 the value just before actually returning. Stack based buffer
1233 overflows (that need to overwrite this return address) now also
1234 overwrite the canary, which gets detected and the attack is then
1235 neutralized via a kernel panic.
1237 This feature requires gcc version 4.2 or above, or a distribution
1238 gcc with the feature backported. Older versions are automatically
1239 detected and for those versions, this configuration option is ignored.
1241 config CC_STACKPROTECTOR_ALL
1242 bool "Use stack-protector for all functions"
1243 depends on CC_STACKPROTECTOR
1245 Normally, GCC only inserts the canary value protection for
1246 functions that use large-ish on-stack buffers. By enabling
1247 this option, GCC will be asked to do this for ALL functions.
1249 source kernel/Kconfig.hz
1252 bool "kexec system call"
1253 depends on X86_BIOS_REBOOT
1255 kexec is a system call that implements the ability to shutdown your
1256 current kernel, and to start another kernel. It is like a reboot
1257 but it is independent of the system firmware. And like a reboot
1258 you can start any kernel with it, not just Linux.
1260 The name comes from the similarity to the exec system call.
1262 It is an ongoing process to be certain the hardware in a machine
1263 is properly shutdown, so do not be surprised if this code does not
1264 initially work for you. It may help to enable device hotplugging
1265 support. As of this writing the exact hardware interface is
1266 strongly in flux, so no good recommendation can be made.
1269 bool "kernel crash dumps (EXPERIMENTAL)"
1270 depends on X86_64 || (X86_32 && HIGHMEM)
1272 Generate crash dump after being started by kexec.
1273 This should be normally only set in special crash dump kernels
1274 which are loaded in the main kernel with kexec-tools into
1275 a specially reserved region and then later executed after
1276 a crash by kdump/kexec. The crash dump kernel must be compiled
1277 to a memory address not used by the main kernel or BIOS using
1278 PHYSICAL_START, or it must be built as a relocatable image
1279 (CONFIG_RELOCATABLE=y).
1280 For more details see Documentation/kdump/kdump.txt
1282 config PHYSICAL_START
1283 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1284 default "0x1000000" if X86_NUMAQ
1285 default "0x200000" if X86_64
1288 This gives the physical address where the kernel is loaded.
1290 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1291 bzImage will decompress itself to above physical address and
1292 run from there. Otherwise, bzImage will run from the address where
1293 it has been loaded by the boot loader and will ignore above physical
1296 In normal kdump cases one does not have to set/change this option
1297 as now bzImage can be compiled as a completely relocatable image
1298 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1299 address. This option is mainly useful for the folks who don't want
1300 to use a bzImage for capturing the crash dump and want to use a
1301 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1302 to be specifically compiled to run from a specific memory area
1303 (normally a reserved region) and this option comes handy.
1305 So if you are using bzImage for capturing the crash dump, leave
1306 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1307 Otherwise if you plan to use vmlinux for capturing the crash dump
1308 change this value to start of the reserved region (Typically 16MB
1309 0x1000000). In other words, it can be set based on the "X" value as
1310 specified in the "crashkernel=YM@XM" command line boot parameter
1311 passed to the panic-ed kernel. Typically this parameter is set as
1312 crashkernel=64M@16M. Please take a look at
1313 Documentation/kdump/kdump.txt for more details about crash dumps.
1315 Usage of bzImage for capturing the crash dump is recommended as
1316 one does not have to build two kernels. Same kernel can be used
1317 as production kernel and capture kernel. Above option should have
1318 gone away after relocatable bzImage support is introduced. But it
1319 is present because there are users out there who continue to use
1320 vmlinux for dump capture. This option should go away down the
1323 Don't change this unless you know what you are doing.
1326 bool "Build a relocatable kernel (EXPERIMENTAL)"
1327 depends on EXPERIMENTAL
1329 This builds a kernel image that retains relocation information
1330 so it can be loaded someplace besides the default 1MB.
1331 The relocations tend to make the kernel binary about 10% larger,
1332 but are discarded at runtime.
1334 One use is for the kexec on panic case where the recovery kernel
1335 must live at a different physical address than the primary
1338 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1339 it has been loaded at and the compile time physical address
1340 (CONFIG_PHYSICAL_START) is ignored.
1342 config PHYSICAL_ALIGN
1344 prompt "Alignment value to which kernel should be aligned" if X86_32
1345 default "0x100000" if X86_32
1346 default "0x200000" if X86_64
1347 range 0x2000 0x400000
1349 This value puts the alignment restrictions on physical address
1350 where kernel is loaded and run from. Kernel is compiled for an
1351 address which meets above alignment restriction.
1353 If bootloader loads the kernel at a non-aligned address and
1354 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1355 address aligned to above value and run from there.
1357 If bootloader loads the kernel at a non-aligned address and
1358 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1359 load address and decompress itself to the address it has been
1360 compiled for and run from there. The address for which kernel is
1361 compiled already meets above alignment restrictions. Hence the
1362 end result is that kernel runs from a physical address meeting
1363 above alignment restrictions.
1365 Don't change this unless you know what you are doing.
1368 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1369 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1371 Say Y here to experiment with turning CPUs off and on, and to
1372 enable suspend on SMP systems. CPUs can be controlled through
1373 /sys/devices/system/cpu.
1374 Say N if you want to disable CPU hotplug and don't need to
1379 prompt "Compat VDSO support"
1380 depends on X86_32 || IA32_EMULATION
1382 Map the 32-bit VDSO to the predictable old-style address too.
1384 Say N here if you are running a sufficiently recent glibc
1385 version (2.3.3 or later), to remove the high-mapped
1386 VDSO mapping and to exclusively use the randomized VDSO.
1392 config ARCH_ENABLE_MEMORY_HOTPLUG
1394 depends on X86_64 || (X86_32 && HIGHMEM)
1396 config HAVE_ARCH_EARLY_PFN_TO_NID
1400 menu "Power management options"
1401 depends on !X86_VOYAGER
1403 config ARCH_HIBERNATION_HEADER
1405 depends on X86_64 && HIBERNATION
1407 source "kernel/power/Kconfig"
1409 source "drivers/acpi/Kconfig"
1414 depends on APM || APM_MODULE
1417 tristate "APM (Advanced Power Management) BIOS support"
1418 depends on X86_32 && PM_SLEEP
1420 APM is a BIOS specification for saving power using several different
1421 techniques. This is mostly useful for battery powered laptops with
1422 APM compliant BIOSes. If you say Y here, the system time will be
1423 reset after a RESUME operation, the /proc/apm device will provide
1424 battery status information, and user-space programs will receive
1425 notification of APM "events" (e.g. battery status change).
1427 If you select "Y" here, you can disable actual use of the APM
1428 BIOS by passing the "apm=off" option to the kernel at boot time.
1430 Note that the APM support is almost completely disabled for
1431 machines with more than one CPU.
1433 In order to use APM, you will need supporting software. For location
1434 and more information, read <file:Documentation/power/pm.txt> and the
1435 Battery Powered Linux mini-HOWTO, available from
1436 <http://www.tldp.org/docs.html#howto>.
1438 This driver does not spin down disk drives (see the hdparm(8)
1439 manpage ("man 8 hdparm") for that), and it doesn't turn off
1440 VESA-compliant "green" monitors.
1442 This driver does not support the TI 4000M TravelMate and the ACER
1443 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1444 desktop machines also don't have compliant BIOSes, and this driver
1445 may cause those machines to panic during the boot phase.
1447 Generally, if you don't have a battery in your machine, there isn't
1448 much point in using this driver and you should say N. If you get
1449 random kernel OOPSes or reboots that don't seem to be related to
1450 anything, try disabling/enabling this option (or disabling/enabling
1453 Some other things you should try when experiencing seemingly random,
1456 1) make sure that you have enough swap space and that it is
1458 2) pass the "no-hlt" option to the kernel
1459 3) switch on floating point emulation in the kernel and pass
1460 the "no387" option to the kernel
1461 4) pass the "floppy=nodma" option to the kernel
1462 5) pass the "mem=4M" option to the kernel (thereby disabling
1463 all but the first 4 MB of RAM)
1464 6) make sure that the CPU is not over clocked.
1465 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1466 8) disable the cache from your BIOS settings
1467 9) install a fan for the video card or exchange video RAM
1468 10) install a better fan for the CPU
1469 11) exchange RAM chips
1470 12) exchange the motherboard.
1472 To compile this driver as a module, choose M here: the
1473 module will be called apm.
1477 config APM_IGNORE_USER_SUSPEND
1478 bool "Ignore USER SUSPEND"
1480 This option will ignore USER SUSPEND requests. On machines with a
1481 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1482 series notebooks, it is necessary to say Y because of a BIOS bug.
1484 config APM_DO_ENABLE
1485 bool "Enable PM at boot time"
1487 Enable APM features at boot time. From page 36 of the APM BIOS
1488 specification: "When disabled, the APM BIOS does not automatically
1489 power manage devices, enter the Standby State, enter the Suspend
1490 State, or take power saving steps in response to CPU Idle calls."
1491 This driver will make CPU Idle calls when Linux is idle (unless this
1492 feature is turned off -- see "Do CPU IDLE calls", below). This
1493 should always save battery power, but more complicated APM features
1494 will be dependent on your BIOS implementation. You may need to turn
1495 this option off if your computer hangs at boot time when using APM
1496 support, or if it beeps continuously instead of suspending. Turn
1497 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1498 T400CDT. This is off by default since most machines do fine without
1502 bool "Make CPU Idle calls when idle"
1504 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1505 On some machines, this can activate improved power savings, such as
1506 a slowed CPU clock rate, when the machine is idle. These idle calls
1507 are made after the idle loop has run for some length of time (e.g.,
1508 333 mS). On some machines, this will cause a hang at boot time or
1509 whenever the CPU becomes idle. (On machines with more than one CPU,
1510 this option does nothing.)
1512 config APM_DISPLAY_BLANK
1513 bool "Enable console blanking using APM"
1515 Enable console blanking using the APM. Some laptops can use this to
1516 turn off the LCD backlight when the screen blanker of the Linux
1517 virtual console blanks the screen. Note that this is only used by
1518 the virtual console screen blanker, and won't turn off the backlight
1519 when using the X Window system. This also doesn't have anything to
1520 do with your VESA-compliant power-saving monitor. Further, this
1521 option doesn't work for all laptops -- it might not turn off your
1522 backlight at all, or it might print a lot of errors to the console,
1523 especially if you are using gpm.
1525 config APM_ALLOW_INTS
1526 bool "Allow interrupts during APM BIOS calls"
1528 Normally we disable external interrupts while we are making calls to
1529 the APM BIOS as a measure to lessen the effects of a badly behaving
1530 BIOS implementation. The BIOS should reenable interrupts if it
1531 needs to. Unfortunately, some BIOSes do not -- especially those in
1532 many of the newer IBM Thinkpads. If you experience hangs when you
1533 suspend, try setting this to Y. Otherwise, say N.
1535 config APM_REAL_MODE_POWER_OFF
1536 bool "Use real mode APM BIOS call to power off"
1538 Use real mode APM BIOS calls to switch off the computer. This is
1539 a work-around for a number of buggy BIOSes. Switch this option on if
1540 your computer crashes instead of powering off properly.
1544 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1546 source "drivers/cpuidle/Kconfig"
1551 menu "Bus options (PCI etc.)"
1556 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1558 Find out whether you have a PCI motherboard. PCI is the name of a
1559 bus system, i.e. the way the CPU talks to the other stuff inside
1560 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1561 VESA. If you have PCI, say Y, otherwise N.
1564 prompt "PCI access mode"
1565 depends on X86_32 && PCI
1568 On PCI systems, the BIOS can be used to detect the PCI devices and
1569 determine their configuration. However, some old PCI motherboards
1570 have BIOS bugs and may crash if this is done. Also, some embedded
1571 PCI-based systems don't have any BIOS at all. Linux can also try to
1572 detect the PCI hardware directly without using the BIOS.
1574 With this option, you can specify how Linux should detect the
1575 PCI devices. If you choose "BIOS", the BIOS will be used,
1576 if you choose "Direct", the BIOS won't be used, and if you
1577 choose "MMConfig", then PCI Express MMCONFIG will be used.
1578 If you choose "Any", the kernel will try MMCONFIG, then the
1579 direct access method and falls back to the BIOS if that doesn't
1580 work. If unsure, go with the default, which is "Any".
1585 config PCI_GOMMCONFIG
1602 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1604 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1607 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1611 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1615 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1622 bool "Support mmconfig PCI config space access"
1623 depends on X86_64 && PCI && ACPI
1626 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1627 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1629 DMA remapping (DMAR) devices support enables independent address
1630 translations for Direct Memory Access (DMA) from devices.
1631 These DMA remapping devices are reported via ACPI tables
1632 and include PCI device scope covered by these DMA
1637 prompt "Support for Graphics workaround"
1640 Current Graphics drivers tend to use physical address
1641 for DMA and avoid using DMA APIs. Setting this config
1642 option permits the IOMMU driver to set a unity map for
1643 all the OS-visible memory. Hence the driver can continue
1644 to use physical addresses for DMA.
1646 config DMAR_FLOPPY_WA
1650 Floppy disk drivers are know to bypass DMA API calls
1651 thereby failing to work when IOMMU is enabled. This
1652 workaround will setup a 1:1 mapping for the first
1653 16M to make floppy (an ISA device) work.
1656 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1657 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1659 Supports Interrupt remapping for IO-APIC and MSI devices.
1660 To use x2apic mode in the CPU's which support x2APIC enhancements or
1661 to support platforms with CPU's having > 8 bit APIC ID, say Y.
1663 source "drivers/pci/pcie/Kconfig"
1665 source "drivers/pci/Kconfig"
1667 # x86_64 have no ISA slots, but do have ISA-style DMA.
1675 depends on !X86_VOYAGER
1677 Find out whether you have ISA slots on your motherboard. ISA is the
1678 name of a bus system, i.e. the way the CPU talks to the other stuff
1679 inside your box. Other bus systems are PCI, EISA, MicroChannel
1680 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1681 newer boards don't support it. If you have ISA, say Y, otherwise N.
1687 The Extended Industry Standard Architecture (EISA) bus was
1688 developed as an open alternative to the IBM MicroChannel bus.
1690 The EISA bus provided some of the features of the IBM MicroChannel
1691 bus while maintaining backward compatibility with cards made for
1692 the older ISA bus. The EISA bus saw limited use between 1988 and
1693 1995 when it was made obsolete by the PCI bus.
1695 Say Y here if you are building a kernel for an EISA-based machine.
1699 source "drivers/eisa/Kconfig"
1702 bool "MCA support" if !X86_VOYAGER
1703 default y if X86_VOYAGER
1705 MicroChannel Architecture is found in some IBM PS/2 machines and
1706 laptops. It is a bus system similar to PCI or ISA. See
1707 <file:Documentation/mca.txt> (and especially the web page given
1708 there) before attempting to build an MCA bus kernel.
1710 source "drivers/mca/Kconfig"
1713 tristate "NatSemi SCx200 support"
1714 depends on !X86_VOYAGER
1716 This provides basic support for National Semiconductor's
1717 (now AMD's) Geode processors. The driver probes for the
1718 PCI-IDs of several on-chip devices, so its a good dependency
1719 for other scx200_* drivers.
1721 If compiled as a module, the driver is named scx200.
1723 config SCx200HR_TIMER
1724 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1725 depends on SCx200 && GENERIC_TIME
1728 This driver provides a clocksource built upon the on-chip
1729 27MHz high-resolution timer. Its also a workaround for
1730 NSC Geode SC-1100's buggy TSC, which loses time when the
1731 processor goes idle (as is done by the scheduler). The
1732 other workaround is idle=poll boot option.
1734 config GEODE_MFGPT_TIMER
1736 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1737 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1739 This driver provides a clock event source based on the MFGPT
1740 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1741 MFGPTs have a better resolution and max interval than the
1742 generic PIT, and are suitable for use as high-res timers.
1745 bool "One Laptop Per Child support"
1748 Add support for detecting the unique features of the OLPC
1755 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1757 source "drivers/pcmcia/Kconfig"
1759 source "drivers/pci/hotplug/Kconfig"
1764 menu "Executable file formats / Emulations"
1766 source "fs/Kconfig.binfmt"
1768 config IA32_EMULATION
1769 bool "IA32 Emulation"
1771 select COMPAT_BINFMT_ELF
1773 Include code to run 32-bit programs under a 64-bit kernel. You should
1774 likely turn this on, unless you're 100% sure that you don't have any
1775 32-bit programs left.
1778 tristate "IA32 a.out support"
1779 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1781 Support old a.out binaries in the 32bit emulation.
1785 depends on IA32_EMULATION
1787 config COMPAT_FOR_U64_ALIGNMENT
1791 config SYSVIPC_COMPAT
1793 depends on X86_64 && COMPAT && SYSVIPC
1798 source "net/Kconfig"
1800 source "drivers/Kconfig"
1802 source "drivers/firmware/Kconfig"
1806 source "arch/x86/Kconfig.debug"
1808 source "security/Kconfig"
1810 source "crypto/Kconfig"
1812 source "arch/x86/kvm/Kconfig"
1814 source "lib/Kconfig"
projects / linux-2.6 / blob