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 HAVE_KRETPROBES
27 select HAVE_DYNAMIC_FTRACE
29 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
30 select HAVE_ARCH_KGDB if !X86_VOYAGER
34 default "arch/x86/configs/i386_defconfig" if X86_32
35 default "arch/x86/configs/x86_64_defconfig" if X86_64
38 config GENERIC_LOCKBREAK
44 config GENERIC_CMOS_UPDATE
47 config CLOCKSOURCE_WATCHDOG
50 config GENERIC_CLOCKEVENTS
53 config GENERIC_CLOCKEVENTS_BROADCAST
55 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
57 config LOCKDEP_SUPPORT
60 config STACKTRACE_SUPPORT
63 config HAVE_LATENCYTOP_SUPPORT
66 config FAST_CMPXCHG_LOCAL
79 config GENERIC_ISA_DMA
89 config GENERIC_HWEIGHT
95 config ARCH_MAY_HAVE_PC_FDC
98 config RWSEM_GENERIC_SPINLOCK
101 config RWSEM_XCHGADD_ALGORITHM
104 config ARCH_HAS_ILOG2_U32
107 config ARCH_HAS_ILOG2_U64
110 config ARCH_HAS_CPU_IDLE_WAIT
113 config GENERIC_CALIBRATE_DELAY
116 config GENERIC_TIME_VSYSCALL
120 config ARCH_HAS_CPU_RELAX
123 config ARCH_HAS_CACHE_LINE_SIZE
126 config HAVE_SETUP_PER_CPU_AREA
127 def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER)
129 config HAVE_CPUMASK_OF_CPU_MAP
132 config ARCH_HIBERNATION_POSSIBLE
134 depends on !SMP || !X86_VOYAGER
136 config ARCH_SUSPEND_POSSIBLE
138 depends on !X86_VOYAGER
144 config ARCH_POPULATES_NODE_MAP
151 config ARCH_SUPPORTS_AOUT
154 config ARCH_SUPPORTS_OPTIMIZED_INLINING
157 # Use the generic interrupt handling code in kernel/irq/:
158 config GENERIC_HARDIRQS
162 config GENERIC_IRQ_PROBE
166 config GENERIC_PENDING_IRQ
168 depends on GENERIC_HARDIRQS && SMP
173 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
174 select USE_GENERIC_SMP_HELPERS
179 depends on X86_32 && SMP
183 depends on X86_64 && SMP
188 depends on (X86_32 && !X86_VOYAGER) || X86_64
191 config X86_BIOS_REBOOT
193 depends on !X86_VOYAGER
196 config X86_TRAMPOLINE
198 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
203 source "init/Kconfig"
205 menu "Processor type and features"
207 source "kernel/time/Kconfig"
210 bool "Symmetric multi-processing support"
212 This enables support for systems with more than one CPU. If you have
213 a system with only one CPU, like most personal computers, say N. If
214 you have a system with more than one CPU, say Y.
216 If you say N here, the kernel will run on single and multiprocessor
217 machines, but will use only one CPU of a multiprocessor machine. If
218 you say Y here, the kernel will run on many, but not all,
219 singleprocessor machines. On a singleprocessor machine, the kernel
220 will run faster if you say N here.
222 Note that if you say Y here and choose architecture "586" or
223 "Pentium" under "Processor family", the kernel will not work on 486
224 architectures. Similarly, multiprocessor kernels for the "PPro"
225 architecture may not work on all Pentium based boards.
227 People using multiprocessor machines who say Y here should also say
228 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
229 Management" code will be disabled if you say Y here.
231 See also <file:Documentation/i386/IO-APIC.txt>,
232 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
233 <http://www.tldp.org/docs.html#howto>.
235 If you don't know what to do here, say N.
237 config X86_FIND_SMP_CONFIG
239 depends on X86_MPPARSE || X86_VOYAGER
244 bool "Enable MPS table"
245 depends on X86_LOCAL_APIC
247 For old smp systems that do not have proper acpi support. Newer systems
248 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
254 depends on X86_LOCAL_APIC
258 prompt "Subarchitecture Type"
264 Choose this option if your computer is a standard PC or compatible.
270 Select this for an AMD Elan processor.
272 Do not use this option for K6/Athlon/Opteron processors!
274 If unsure, choose "PC-compatible" instead.
278 depends on X86_32 && (SMP || BROKEN) && !PCI
280 Voyager is an MCA-based 32-way capable SMP architecture proprietary
281 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
285 If you do not specifically know you have a Voyager based machine,
286 say N here, otherwise the kernel you build will not be bootable.
288 config X86_GENERICARCH
289 bool "Generic architecture"
292 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
293 subarchitectures. It is intended for a generic binary kernel.
294 if you select them all, kernel will probe it one by one. and will
300 bool "NUMAQ (IBM/Sequent)"
301 depends on SMP && X86_32 && PCI && X86_MPPARSE
304 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
305 NUMA multiquad box. This changes the way that processors are
306 bootstrapped, and uses Clustered Logical APIC addressing mode instead
307 of Flat Logical. You will need a new lynxer.elf file to flash your
308 firmware with - send email to <Martin.Bligh@us.ibm.com>.
311 bool "Summit/EXA (IBM x440)"
312 depends on X86_32 && SMP
314 This option is needed for IBM systems that use the Summit/EXA chipset.
315 In particular, it is needed for the x440.
318 bool "Support for Unisys ES7000 IA32 series"
319 depends on X86_32 && SMP
321 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
322 supposed to run on an IA32-based Unisys ES7000 system.
325 bool "Support for big SMP systems with more than 8 CPUs"
326 depends on X86_32 && SMP
328 This option is needed for the systems that have more than 8 CPUs
329 and if the system is not of any sub-arch type above.
334 bool "RDC R-321x SoC"
337 select X86_REBOOTFIXUPS
343 This option is needed for RDC R-321x system-on-chip, also known
345 If you don't have one of these chips, you should say N here.
348 bool "Support for ScaleMP vSMP"
350 depends on X86_64 && PCI
352 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
353 supposed to run on these EM64T-based machines. Only choose this option
354 if you have one of these machines.
359 bool "SGI 320/540 (Visual Workstation)"
360 depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT
362 The SGI Visual Workstation series is an IA32-based workstation
363 based on SGI systems chips with some legacy PC hardware attached.
365 Say Y here to create a kernel to run on the SGI 320 or 540.
367 A kernel compiled for the Visual Workstation will run on general
368 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
370 config SCHED_NO_NO_OMIT_FRAME_POINTER
372 prompt "Single-depth WCHAN output"
375 Calculate simpler /proc/<PID>/wchan values. If this option
376 is disabled then wchan values will recurse back to the
377 caller function. This provides more accurate wchan values,
378 at the expense of slightly more scheduling overhead.
380 If in doubt, say "Y".
382 menuconfig PARAVIRT_GUEST
383 bool "Paravirtualized guest support"
385 Say Y here to get to see options related to running Linux under
386 various hypervisors. This option alone does not add any kernel code.
388 If you say N, all options in this submenu will be skipped and disabled.
392 source "arch/x86/xen/Kconfig"
395 bool "VMI Guest support"
398 depends on !X86_VOYAGER
400 VMI provides a paravirtualized interface to the VMware ESX server
401 (it could be used by other hypervisors in theory too, but is not
402 at the moment), by linking the kernel to a GPL-ed ROM module
403 provided by the hypervisor.
406 bool "KVM paravirtualized clock"
408 select PARAVIRT_CLOCK
409 depends on !X86_VOYAGER
411 Turning on this option will allow you to run a paravirtualized clock
412 when running over the KVM hypervisor. Instead of relying on a PIT
413 (or probably other) emulation by the underlying device model, the host
414 provides the guest with timing infrastructure such as time of day, and
418 bool "KVM Guest support"
420 depends on !X86_VOYAGER
422 This option enables various optimizations for running under the KVM
425 source "arch/x86/lguest/Kconfig"
428 bool "Enable paravirtualization code"
429 depends on !X86_VOYAGER
431 This changes the kernel so it can modify itself when it is run
432 under a hypervisor, potentially improving performance significantly
433 over full virtualization. However, when run without a hypervisor
434 the kernel is theoretically slower and slightly larger.
436 config PARAVIRT_CLOCK
442 config PARAVIRT_DEBUG
443 bool "paravirt-ops debugging"
444 depends on PARAVIRT && DEBUG_KERNEL
446 Enable to debug paravirt_ops internals. Specifically, BUG if
447 a paravirt_op is missing when it is called.
452 This option adds a kernel parameter 'memtest', which allows memtest
454 memtest=0, mean disabled; -- default
455 memtest=1, mean do 1 test pattern;
457 memtest=4, mean do 4 test patterns.
458 If you are unsure how to answer this question, answer N.
460 config X86_SUMMIT_NUMA
462 depends on X86_32 && NUMA && X86_GENERICARCH
464 config X86_CYCLONE_TIMER
466 depends on X86_GENERICARCH
468 config ES7000_CLUSTERED_APIC
470 depends on SMP && X86_ES7000 && MPENTIUMIII
472 source "arch/x86/Kconfig.cpu"
476 prompt "HPET Timer Support" if X86_32
478 Use the IA-PC HPET (High Precision Event Timer) to manage
479 time in preference to the PIT and RTC, if a HPET is
481 HPET is the next generation timer replacing legacy 8254s.
482 The HPET provides a stable time base on SMP
483 systems, unlike the TSC, but it is more expensive to access,
484 as it is off-chip. You can find the HPET spec at
485 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
487 You can safely choose Y here. However, HPET will only be
488 activated if the platform and the BIOS support this feature.
489 Otherwise the 8254 will be used for timing services.
491 Choose N to continue using the legacy 8254 timer.
493 config HPET_EMULATE_RTC
495 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
497 # Mark as embedded because too many people got it wrong.
498 # The code disables itself when not needed.
501 bool "Enable DMI scanning" if EMBEDDED
503 Enabled scanning of DMI to identify machine quirks. Say Y
504 here unless you have verified that your setup is not
505 affected by entries in the DMI blacklist. Required by PNP
509 bool "GART IOMMU support" if EMBEDDED
513 depends on X86_64 && PCI
515 Support for full DMA access of devices with 32bit memory access only
516 on systems with more than 3GB. This is usually needed for USB,
517 sound, many IDE/SATA chipsets and some other devices.
518 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
519 based hardware IOMMU and a software bounce buffer based IOMMU used
520 on Intel systems and as fallback.
521 The code is only active when needed (enough memory and limited
522 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
526 bool "IBM Calgary IOMMU support"
528 depends on X86_64 && PCI && EXPERIMENTAL
530 Support for hardware IOMMUs in IBM's xSeries x366 and x460
531 systems. Needed to run systems with more than 3GB of memory
532 properly with 32-bit PCI devices that do not support DAC
533 (Double Address Cycle). Calgary also supports bus level
534 isolation, where all DMAs pass through the IOMMU. This
535 prevents them from going anywhere except their intended
536 destination. This catches hard-to-find kernel bugs and
537 mis-behaving drivers and devices that do not use the DMA-API
538 properly to set up their DMA buffers. The IOMMU can be
539 turned off at boot time with the iommu=off parameter.
540 Normally the kernel will make the right choice by itself.
543 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
545 prompt "Should Calgary be enabled by default?"
546 depends on CALGARY_IOMMU
548 Should Calgary be enabled by default? if you choose 'y', Calgary
549 will be used (if it exists). If you choose 'n', Calgary will not be
550 used even if it exists. If you choose 'n' and would like to use
551 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
555 bool "AMD IOMMU support"
557 depends on X86_64 && PCI && ACPI
559 With this option you can enable support for AMD IOMMU hardware in
560 your system. An IOMMU is a hardware component which provides
561 remapping of DMA memory accesses from devices. With an AMD IOMMU you
562 can isolate the the DMA memory of different devices and protect the
563 system from misbehaving device drivers or hardware.
565 You can find out if your system has an AMD IOMMU if you look into
566 your BIOS for an option to enable it or if you have an IVRS ACPI
569 # need this always selected by IOMMU for the VIA workaround
573 Support for software bounce buffers used on x86-64 systems
574 which don't have a hardware IOMMU (e.g. the current generation
575 of Intel's x86-64 CPUs). Using this PCI devices which can only
576 access 32-bits of memory can be used on systems with more than
577 3 GB of memory. If unsure, say Y.
580 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
582 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
583 depends on X86_64 && SMP
586 Configure maximum number of CPUS and NUMA Nodes for this architecture.
597 int "Maximum number of CPUs (2-4096)"
600 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
603 This allows you to specify the maximum number of CPUs which this
604 kernel will support. The maximum supported value is 4096 and the
605 minimum value which makes sense is 2.
607 This is purely to save memory - each supported CPU adds
608 approximately eight kilobytes to the kernel image.
612 bool "SMT (Hyperthreading) scheduler support"
615 SMT scheduler support improves the CPU scheduler's decision making
616 when dealing with Intel Pentium 4 chips with HyperThreading at a
617 cost of slightly increased overhead in some places. If unsure say
622 prompt "Multi-core scheduler support"
625 Multi-core scheduler support improves the CPU scheduler's decision
626 making when dealing with multi-core CPU chips at a cost of slightly
627 increased overhead in some places. If unsure say N here.
629 source "kernel/Kconfig.preempt"
632 bool "Local APIC support on uniprocessors"
633 depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH)
635 A local APIC (Advanced Programmable Interrupt Controller) is an
636 integrated interrupt controller in the CPU. If you have a single-CPU
637 system which has a processor with a local APIC, you can say Y here to
638 enable and use it. If you say Y here even though your machine doesn't
639 have a local APIC, then the kernel will still run with no slowdown at
640 all. The local APIC supports CPU-generated self-interrupts (timer,
641 performance counters), and the NMI watchdog which detects hard
645 bool "IO-APIC support on uniprocessors"
646 depends on X86_UP_APIC
648 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
649 SMP-capable replacement for PC-style interrupt controllers. Most
650 SMP systems and many recent uniprocessor systems have one.
652 If you have a single-CPU system with an IO-APIC, you can say Y here
653 to use it. If you say Y here even though your machine doesn't have
654 an IO-APIC, then the kernel will still run with no slowdown at all.
656 config X86_LOCAL_APIC
658 depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
662 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
664 config X86_VISWS_APIC
666 depends on X86_32 && X86_VISWS
669 bool "Machine Check Exception"
670 depends on !X86_VOYAGER
672 Machine Check Exception support allows the processor to notify the
673 kernel if it detects a problem (e.g. overheating, component failure).
674 The action the kernel takes depends on the severity of the problem,
675 ranging from a warning message on the console, to halting the machine.
676 Your processor must be a Pentium or newer to support this - check the
677 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
678 have a design flaw which leads to false MCE events - hence MCE is
679 disabled on all P5 processors, unless explicitly enabled with "mce"
680 as a boot argument. Similarly, if MCE is built in and creates a
681 problem on some new non-standard machine, you can boot with "nomce"
682 to disable it. MCE support simply ignores non-MCE processors like
683 the 386 and 486, so nearly everyone can say Y here.
687 prompt "Intel MCE features"
688 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
690 Additional support for intel specific MCE features such as
695 prompt "AMD MCE features"
696 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
698 Additional support for AMD specific MCE features such as
699 the DRAM Error Threshold.
701 config X86_MCE_NONFATAL
702 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
703 depends on X86_32 && X86_MCE
705 Enabling this feature starts a timer that triggers every 5 seconds which
706 will look at the machine check registers to see if anything happened.
707 Non-fatal problems automatically get corrected (but still logged).
708 Disable this if you don't want to see these messages.
709 Seeing the messages this option prints out may be indicative of dying
710 or out-of-spec (ie, overclocked) hardware.
711 This option only does something on certain CPUs.
712 (AMD Athlon/Duron and Intel Pentium 4)
714 config X86_MCE_P4THERMAL
715 bool "check for P4 thermal throttling interrupt."
716 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
718 Enabling this feature will cause a message to be printed when the P4
719 enters thermal throttling.
722 bool "Enable VM86 support" if EMBEDDED
726 This option is required by programs like DOSEMU to run 16-bit legacy
727 code on X86 processors. It also may be needed by software like
728 XFree86 to initialize some video cards via BIOS. Disabling this
729 option saves about 6k.
732 tristate "Toshiba Laptop support"
735 This adds a driver to safely access the System Management Mode of
736 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
737 not work on models with a Phoenix BIOS. The System Management Mode
738 is used to set the BIOS and power saving options on Toshiba portables.
740 For information on utilities to make use of this driver see the
741 Toshiba Linux utilities web site at:
742 <http://www.buzzard.org.uk/toshiba/>.
744 Say Y if you intend to run this kernel on a Toshiba portable.
748 tristate "Dell laptop support"
750 This adds a driver to safely access the System Management Mode
751 of the CPU on the Dell Inspiron 8000. The System Management Mode
752 is used to read cpu temperature and cooling fan status and to
753 control the fans on the I8K portables.
755 This driver has been tested only on the Inspiron 8000 but it may
756 also work with other Dell laptops. You can force loading on other
757 models by passing the parameter `force=1' to the module. Use at
760 For information on utilities to make use of this driver see the
761 I8K Linux utilities web site at:
762 <http://people.debian.org/~dz/i8k/>
764 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
767 config X86_REBOOTFIXUPS
769 prompt "Enable X86 board specific fixups for reboot"
770 depends on X86_32 && X86
772 This enables chipset and/or board specific fixups to be done
773 in order to get reboot to work correctly. This is only needed on
774 some combinations of hardware and BIOS. The symptom, for which
775 this config is intended, is when reboot ends with a stalled/hung
778 Currently, the only fixup is for the Geode machines using
779 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
781 Say Y if you want to enable the fixup. Currently, it's safe to
782 enable this option even if you don't need it.
786 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
789 If you say Y here, you will be able to update the microcode on
790 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
791 Pentium III, Pentium 4, Xeon etc. You will obviously need the
792 actual microcode binary data itself which is not shipped with the
795 For latest news and information on obtaining all the required
796 ingredients for this driver, check:
797 <http://www.urbanmyth.org/microcode/>.
799 To compile this driver as a module, choose M here: the
800 module will be called microcode.
802 config MICROCODE_OLD_INTERFACE
807 tristate "/dev/cpu/*/msr - Model-specific register support"
809 This device gives privileged processes access to the x86
810 Model-Specific Registers (MSRs). It is a character device with
811 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
812 MSR accesses are directed to a specific CPU on multi-processor
816 tristate "/dev/cpu/*/cpuid - CPU information support"
818 This device gives processes access to the x86 CPUID instruction to
819 be executed on a specific processor. It is a character device
820 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
824 prompt "High Memory Support"
825 default HIGHMEM4G if !X86_NUMAQ
826 default HIGHMEM64G if X86_NUMAQ
831 depends on !X86_NUMAQ
833 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
834 However, the address space of 32-bit x86 processors is only 4
835 Gigabytes large. That means that, if you have a large amount of
836 physical memory, not all of it can be "permanently mapped" by the
837 kernel. The physical memory that's not permanently mapped is called
840 If you are compiling a kernel which will never run on a machine with
841 more than 1 Gigabyte total physical RAM, answer "off" here (default
842 choice and suitable for most users). This will result in a "3GB/1GB"
843 split: 3GB are mapped so that each process sees a 3GB virtual memory
844 space and the remaining part of the 4GB virtual memory space is used
845 by the kernel to permanently map as much physical memory as
848 If the machine has between 1 and 4 Gigabytes physical RAM, then
851 If more than 4 Gigabytes is used then answer "64GB" here. This
852 selection turns Intel PAE (Physical Address Extension) mode on.
853 PAE implements 3-level paging on IA32 processors. PAE is fully
854 supported by Linux, PAE mode is implemented on all recent Intel
855 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
856 then the kernel will not boot on CPUs that don't support PAE!
858 The actual amount of total physical memory will either be
859 auto detected or can be forced by using a kernel command line option
860 such as "mem=256M". (Try "man bootparam" or see the documentation of
861 your boot loader (lilo or loadlin) about how to pass options to the
862 kernel at boot time.)
864 If unsure, say "off".
868 depends on !X86_NUMAQ
870 Select this if you have a 32-bit processor and between 1 and 4
871 gigabytes of physical RAM.
875 depends on !M386 && !M486
878 Select this if you have a 32-bit processor and more than 4
879 gigabytes of physical RAM.
884 depends on EXPERIMENTAL
885 prompt "Memory split" if EMBEDDED
889 Select the desired split between kernel and user memory.
891 If the address range available to the kernel is less than the
892 physical memory installed, the remaining memory will be available
893 as "high memory". Accessing high memory is a little more costly
894 than low memory, as it needs to be mapped into the kernel first.
895 Note that increasing the kernel address space limits the range
896 available to user programs, making the address space there
897 tighter. Selecting anything other than the default 3G/1G split
898 will also likely make your kernel incompatible with binary-only
901 If you are not absolutely sure what you are doing, leave this
905 bool "3G/1G user/kernel split"
906 config VMSPLIT_3G_OPT
908 bool "3G/1G user/kernel split (for full 1G low memory)"
910 bool "2G/2G user/kernel split"
911 config VMSPLIT_2G_OPT
913 bool "2G/2G user/kernel split (for full 2G low memory)"
915 bool "1G/3G user/kernel split"
920 default 0xB0000000 if VMSPLIT_3G_OPT
921 default 0x80000000 if VMSPLIT_2G
922 default 0x78000000 if VMSPLIT_2G_OPT
923 default 0x40000000 if VMSPLIT_1G
929 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
933 prompt "PAE (Physical Address Extension) Support"
934 depends on X86_32 && !HIGHMEM4G
935 select RESOURCES_64BIT
937 PAE is required for NX support, and furthermore enables
938 larger swapspace support for non-overcommit purposes. It
939 has the cost of more pagetable lookup overhead, and also
940 consumes more pagetable space per process.
942 # Common NUMA Features
944 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
946 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
948 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
950 Enable NUMA (Non Uniform Memory Access) support.
951 The kernel will try to allocate memory used by a CPU on the
952 local memory controller of the CPU and add some more
953 NUMA awareness to the kernel.
955 For i386 this is currently highly experimental and should be only
956 used for kernel development. It might also cause boot failures.
957 For x86_64 this is recommended on all multiprocessor Opteron systems.
958 If the system is EM64T, you should say N unless your system is
961 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
962 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
966 prompt "Old style AMD Opteron NUMA detection"
967 depends on X86_64 && NUMA && PCI
969 Enable K8 NUMA node topology detection. You should say Y here if
970 you have a multi processor AMD K8 system. This uses an old
971 method to read the NUMA configuration directly from the builtin
972 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
973 instead, which also takes priority if both are compiled in.
975 config X86_64_ACPI_NUMA
977 prompt "ACPI NUMA detection"
978 depends on X86_64 && NUMA && ACPI && PCI
981 Enable ACPI SRAT based node topology detection.
983 # Some NUMA nodes have memory ranges that span
984 # other nodes. Even though a pfn is valid and
985 # between a node's start and end pfns, it may not
986 # reside on that node. See memmap_init_zone()
988 config NODES_SPAN_OTHER_NODES
990 depends on X86_64_ACPI_NUMA
993 bool "NUMA emulation"
994 depends on X86_64 && NUMA
996 Enable NUMA emulation. A flat machine will be split
997 into virtual nodes when booted with "numa=fake=N", where N is the
998 number of nodes. This is only useful for debugging.
1009 int "Maximum NUMA Nodes (as a power of 2)"
1011 default "6" if X86_64
1012 default "4" if X86_NUMAQ
1014 depends on NEED_MULTIPLE_NODES
1016 Specify the maximum number of NUMA Nodes available on the target
1017 system. Increases memory reserved to accomodate various tables.
1020 config HAVE_ARCH_BOOTMEM_NODE
1022 depends on X86_32 && NUMA
1024 config ARCH_HAVE_MEMORY_PRESENT
1026 depends on X86_32 && DISCONTIGMEM
1028 config NEED_NODE_MEMMAP_SIZE
1030 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1032 config HAVE_ARCH_ALLOC_REMAP
1034 depends on X86_32 && NUMA
1036 config ARCH_FLATMEM_ENABLE
1038 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
1040 config ARCH_DISCONTIGMEM_ENABLE
1042 depends on NUMA && X86_32
1044 config ARCH_DISCONTIGMEM_DEFAULT
1046 depends on NUMA && X86_32
1048 config ARCH_SPARSEMEM_DEFAULT
1052 config ARCH_SPARSEMEM_ENABLE
1054 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1055 select SPARSEMEM_STATIC if X86_32
1056 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1058 config ARCH_SELECT_MEMORY_MODEL
1060 depends on ARCH_SPARSEMEM_ENABLE
1062 config ARCH_MEMORY_PROBE
1064 depends on MEMORY_HOTPLUG
1069 bool "Allocate 3rd-level pagetables from highmem"
1070 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1072 The VM uses one page table entry for each page of physical memory.
1073 For systems with a lot of RAM, this can be wasteful of precious
1074 low memory. Setting this option will put user-space page table
1075 entries in high memory.
1077 config MATH_EMULATION
1079 prompt "Math emulation" if X86_32
1081 Linux can emulate a math coprocessor (used for floating point
1082 operations) if you don't have one. 486DX and Pentium processors have
1083 a math coprocessor built in, 486SX and 386 do not, unless you added
1084 a 487DX or 387, respectively. (The messages during boot time can
1085 give you some hints here ["man dmesg"].) Everyone needs either a
1086 coprocessor or this emulation.
1088 If you don't have a math coprocessor, you need to say Y here; if you
1089 say Y here even though you have a coprocessor, the coprocessor will
1090 be used nevertheless. (This behavior can be changed with the kernel
1091 command line option "no387", which comes handy if your coprocessor
1092 is broken. Try "man bootparam" or see the documentation of your boot
1093 loader (lilo or loadlin) about how to pass options to the kernel at
1094 boot time.) This means that it is a good idea to say Y here if you
1095 intend to use this kernel on different machines.
1097 More information about the internals of the Linux math coprocessor
1098 emulation can be found in <file:arch/x86/math-emu/README>.
1100 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1101 kernel, it won't hurt.
1104 bool "MTRR (Memory Type Range Register) support"
1106 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1107 the Memory Type Range Registers (MTRRs) may be used to control
1108 processor access to memory ranges. This is most useful if you have
1109 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1110 allows bus write transfers to be combined into a larger transfer
1111 before bursting over the PCI/AGP bus. This can increase performance
1112 of image write operations 2.5 times or more. Saying Y here creates a
1113 /proc/mtrr file which may be used to manipulate your processor's
1114 MTRRs. Typically the X server should use this.
1116 This code has a reasonably generic interface so that similar
1117 control registers on other processors can be easily supported
1120 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1121 Registers (ARRs) which provide a similar functionality to MTRRs. For
1122 these, the ARRs are used to emulate the MTRRs.
1123 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1124 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1125 write-combining. All of these processors are supported by this code
1126 and it makes sense to say Y here if you have one of them.
1128 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1129 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1130 can lead to all sorts of problems, so it's good to say Y here.
1132 You can safely say Y even if your machine doesn't have MTRRs, you'll
1133 just add about 9 KB to your kernel.
1135 See <file:Documentation/mtrr.txt> for more information.
1137 config MTRR_SANITIZER
1139 prompt "MTRR cleanup support"
1142 Convert MTRR layout from continuous to discrete, so X drivers can
1143 add writeback entries.
1145 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1146 The largest mtrr entry size for a continous block can be set with
1151 config MTRR_SANITIZER_ENABLE_DEFAULT
1152 int "MTRR cleanup enable value (0-1)"
1155 depends on MTRR_SANITIZER
1157 Enable mtrr cleanup default value
1159 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1160 int "MTRR cleanup spare reg num (0-7)"
1163 depends on MTRR_SANITIZER
1165 mtrr cleanup spare entries default, it can be changed via
1166 mtrr_spare_reg_nr=N on the kernel command line.
1170 prompt "x86 PAT support"
1173 Use PAT attributes to setup page level cache control.
1175 PATs are the modern equivalents of MTRRs and are much more
1176 flexible than MTRRs.
1178 Say N here if you see bootup problems (boot crash, boot hang,
1179 spontaneous reboots) or a non-working video driver.
1185 prompt "EFI runtime service support"
1188 This enables the kernel to use EFI runtime services that are
1189 available (such as the EFI variable services).
1191 This option is only useful on systems that have EFI firmware.
1192 In addition, you should use the latest ELILO loader available
1193 at <http://elilo.sourceforge.net> in order to take advantage
1194 of EFI runtime services. However, even with this option, the
1195 resultant kernel should continue to boot on existing non-EFI
1200 prompt "Enable kernel irq balancing"
1201 depends on X86_32 && SMP && X86_IO_APIC
1203 The default yes will allow the kernel to do irq load balancing.
1204 Saying no will keep the kernel from doing irq load balancing.
1208 prompt "Enable seccomp to safely compute untrusted bytecode"
1211 This kernel feature is useful for number crunching applications
1212 that may need to compute untrusted bytecode during their
1213 execution. By using pipes or other transports made available to
1214 the process as file descriptors supporting the read/write
1215 syscalls, it's possible to isolate those applications in
1216 their own address space using seccomp. Once seccomp is
1217 enabled via /proc/<pid>/seccomp, it cannot be disabled
1218 and the task is only allowed to execute a few safe syscalls
1219 defined by each seccomp mode.
1221 If unsure, say Y. Only embedded should say N here.
1223 config CC_STACKPROTECTOR
1224 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1225 depends on X86_64 && EXPERIMENTAL && BROKEN
1227 This option turns on the -fstack-protector GCC feature. This
1228 feature puts, at the beginning of critical functions, a canary
1229 value on the stack just before the return address, and validates
1230 the value just before actually returning. Stack based buffer
1231 overflows (that need to overwrite this return address) now also
1232 overwrite the canary, which gets detected and the attack is then
1233 neutralized via a kernel panic.
1235 This feature requires gcc version 4.2 or above, or a distribution
1236 gcc with the feature backported. Older versions are automatically
1237 detected and for those versions, this configuration option is ignored.
1239 config CC_STACKPROTECTOR_ALL
1240 bool "Use stack-protector for all functions"
1241 depends on CC_STACKPROTECTOR
1243 Normally, GCC only inserts the canary value protection for
1244 functions that use large-ish on-stack buffers. By enabling
1245 this option, GCC will be asked to do this for ALL functions.
1247 source kernel/Kconfig.hz
1250 bool "kexec system call"
1251 depends on X86_BIOS_REBOOT
1253 kexec is a system call that implements the ability to shutdown your
1254 current kernel, and to start another kernel. It is like a reboot
1255 but it is independent of the system firmware. And like a reboot
1256 you can start any kernel with it, not just Linux.
1258 The name comes from the similarity to the exec system call.
1260 It is an ongoing process to be certain the hardware in a machine
1261 is properly shutdown, so do not be surprised if this code does not
1262 initially work for you. It may help to enable device hotplugging
1263 support. As of this writing the exact hardware interface is
1264 strongly in flux, so no good recommendation can be made.
1267 bool "kernel crash dumps (EXPERIMENTAL)"
1268 depends on X86_64 || (X86_32 && HIGHMEM)
1270 Generate crash dump after being started by kexec.
1271 This should be normally only set in special crash dump kernels
1272 which are loaded in the main kernel with kexec-tools into
1273 a specially reserved region and then later executed after
1274 a crash by kdump/kexec. The crash dump kernel must be compiled
1275 to a memory address not used by the main kernel or BIOS using
1276 PHYSICAL_START, or it must be built as a relocatable image
1277 (CONFIG_RELOCATABLE=y).
1278 For more details see Documentation/kdump/kdump.txt
1280 config PHYSICAL_START
1281 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1282 default "0x1000000" if X86_NUMAQ
1283 default "0x200000" if X86_64
1286 This gives the physical address where the kernel is loaded.
1288 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1289 bzImage will decompress itself to above physical address and
1290 run from there. Otherwise, bzImage will run from the address where
1291 it has been loaded by the boot loader and will ignore above physical
1294 In normal kdump cases one does not have to set/change this option
1295 as now bzImage can be compiled as a completely relocatable image
1296 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1297 address. This option is mainly useful for the folks who don't want
1298 to use a bzImage for capturing the crash dump and want to use a
1299 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1300 to be specifically compiled to run from a specific memory area
1301 (normally a reserved region) and this option comes handy.
1303 So if you are using bzImage for capturing the crash dump, leave
1304 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1305 Otherwise if you plan to use vmlinux for capturing the crash dump
1306 change this value to start of the reserved region (Typically 16MB
1307 0x1000000). In other words, it can be set based on the "X" value as
1308 specified in the "crashkernel=YM@XM" command line boot parameter
1309 passed to the panic-ed kernel. Typically this parameter is set as
1310 crashkernel=64M@16M. Please take a look at
1311 Documentation/kdump/kdump.txt for more details about crash dumps.
1313 Usage of bzImage for capturing the crash dump is recommended as
1314 one does not have to build two kernels. Same kernel can be used
1315 as production kernel and capture kernel. Above option should have
1316 gone away after relocatable bzImage support is introduced. But it
1317 is present because there are users out there who continue to use
1318 vmlinux for dump capture. This option should go away down the
1321 Don't change this unless you know what you are doing.
1324 bool "Build a relocatable kernel (EXPERIMENTAL)"
1325 depends on EXPERIMENTAL
1327 This builds a kernel image that retains relocation information
1328 so it can be loaded someplace besides the default 1MB.
1329 The relocations tend to make the kernel binary about 10% larger,
1330 but are discarded at runtime.
1332 One use is for the kexec on panic case where the recovery kernel
1333 must live at a different physical address than the primary
1336 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1337 it has been loaded at and the compile time physical address
1338 (CONFIG_PHYSICAL_START) is ignored.
1340 config PHYSICAL_ALIGN
1342 prompt "Alignment value to which kernel should be aligned" if X86_32
1343 default "0x100000" if X86_32
1344 default "0x200000" if X86_64
1345 range 0x2000 0x400000
1347 This value puts the alignment restrictions on physical address
1348 where kernel is loaded and run from. Kernel is compiled for an
1349 address which meets above alignment restriction.
1351 If bootloader loads the kernel at a non-aligned address and
1352 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1353 address aligned to above value and run from there.
1355 If bootloader loads the kernel at a non-aligned address and
1356 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1357 load address and decompress itself to the address it has been
1358 compiled for and run from there. The address for which kernel is
1359 compiled already meets above alignment restrictions. Hence the
1360 end result is that kernel runs from a physical address meeting
1361 above alignment restrictions.
1363 Don't change this unless you know what you are doing.
1366 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1367 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1369 Say Y here to experiment with turning CPUs off and on, and to
1370 enable suspend on SMP systems. CPUs can be controlled through
1371 /sys/devices/system/cpu.
1372 Say N if you want to disable CPU hotplug and don't need to
1377 prompt "Compat VDSO support"
1378 depends on X86_32 || IA32_EMULATION
1380 Map the 32-bit VDSO to the predictable old-style address too.
1382 Say N here if you are running a sufficiently recent glibc
1383 version (2.3.3 or later), to remove the high-mapped
1384 VDSO mapping and to exclusively use the randomized VDSO.
1390 config ARCH_ENABLE_MEMORY_HOTPLUG
1392 depends on X86_64 || (X86_32 && HIGHMEM)
1394 config HAVE_ARCH_EARLY_PFN_TO_NID
1398 menu "Power management options"
1399 depends on !X86_VOYAGER
1401 config ARCH_HIBERNATION_HEADER
1403 depends on X86_64 && HIBERNATION
1405 source "kernel/power/Kconfig"
1407 source "drivers/acpi/Kconfig"
1412 depends on APM || APM_MODULE
1415 tristate "APM (Advanced Power Management) BIOS support"
1416 depends on X86_32 && PM_SLEEP
1418 APM is a BIOS specification for saving power using several different
1419 techniques. This is mostly useful for battery powered laptops with
1420 APM compliant BIOSes. If you say Y here, the system time will be
1421 reset after a RESUME operation, the /proc/apm device will provide
1422 battery status information, and user-space programs will receive
1423 notification of APM "events" (e.g. battery status change).
1425 If you select "Y" here, you can disable actual use of the APM
1426 BIOS by passing the "apm=off" option to the kernel at boot time.
1428 Note that the APM support is almost completely disabled for
1429 machines with more than one CPU.
1431 In order to use APM, you will need supporting software. For location
1432 and more information, read <file:Documentation/power/pm.txt> and the
1433 Battery Powered Linux mini-HOWTO, available from
1434 <http://www.tldp.org/docs.html#howto>.
1436 This driver does not spin down disk drives (see the hdparm(8)
1437 manpage ("man 8 hdparm") for that), and it doesn't turn off
1438 VESA-compliant "green" monitors.
1440 This driver does not support the TI 4000M TravelMate and the ACER
1441 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1442 desktop machines also don't have compliant BIOSes, and this driver
1443 may cause those machines to panic during the boot phase.
1445 Generally, if you don't have a battery in your machine, there isn't
1446 much point in using this driver and you should say N. If you get
1447 random kernel OOPSes or reboots that don't seem to be related to
1448 anything, try disabling/enabling this option (or disabling/enabling
1451 Some other things you should try when experiencing seemingly random,
1454 1) make sure that you have enough swap space and that it is
1456 2) pass the "no-hlt" option to the kernel
1457 3) switch on floating point emulation in the kernel and pass
1458 the "no387" option to the kernel
1459 4) pass the "floppy=nodma" option to the kernel
1460 5) pass the "mem=4M" option to the kernel (thereby disabling
1461 all but the first 4 MB of RAM)
1462 6) make sure that the CPU is not over clocked.
1463 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1464 8) disable the cache from your BIOS settings
1465 9) install a fan for the video card or exchange video RAM
1466 10) install a better fan for the CPU
1467 11) exchange RAM chips
1468 12) exchange the motherboard.
1470 To compile this driver as a module, choose M here: the
1471 module will be called apm.
1475 config APM_IGNORE_USER_SUSPEND
1476 bool "Ignore USER SUSPEND"
1478 This option will ignore USER SUSPEND requests. On machines with a
1479 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1480 series notebooks, it is necessary to say Y because of a BIOS bug.
1482 config APM_DO_ENABLE
1483 bool "Enable PM at boot time"
1485 Enable APM features at boot time. From page 36 of the APM BIOS
1486 specification: "When disabled, the APM BIOS does not automatically
1487 power manage devices, enter the Standby State, enter the Suspend
1488 State, or take power saving steps in response to CPU Idle calls."
1489 This driver will make CPU Idle calls when Linux is idle (unless this
1490 feature is turned off -- see "Do CPU IDLE calls", below). This
1491 should always save battery power, but more complicated APM features
1492 will be dependent on your BIOS implementation. You may need to turn
1493 this option off if your computer hangs at boot time when using APM
1494 support, or if it beeps continuously instead of suspending. Turn
1495 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1496 T400CDT. This is off by default since most machines do fine without
1500 bool "Make CPU Idle calls when idle"
1502 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1503 On some machines, this can activate improved power savings, such as
1504 a slowed CPU clock rate, when the machine is idle. These idle calls
1505 are made after the idle loop has run for some length of time (e.g.,
1506 333 mS). On some machines, this will cause a hang at boot time or
1507 whenever the CPU becomes idle. (On machines with more than one CPU,
1508 this option does nothing.)
1510 config APM_DISPLAY_BLANK
1511 bool "Enable console blanking using APM"
1513 Enable console blanking using the APM. Some laptops can use this to
1514 turn off the LCD backlight when the screen blanker of the Linux
1515 virtual console blanks the screen. Note that this is only used by
1516 the virtual console screen blanker, and won't turn off the backlight
1517 when using the X Window system. This also doesn't have anything to
1518 do with your VESA-compliant power-saving monitor. Further, this
1519 option doesn't work for all laptops -- it might not turn off your
1520 backlight at all, or it might print a lot of errors to the console,
1521 especially if you are using gpm.
1523 config APM_ALLOW_INTS
1524 bool "Allow interrupts during APM BIOS calls"
1526 Normally we disable external interrupts while we are making calls to
1527 the APM BIOS as a measure to lessen the effects of a badly behaving
1528 BIOS implementation. The BIOS should reenable interrupts if it
1529 needs to. Unfortunately, some BIOSes do not -- especially those in
1530 many of the newer IBM Thinkpads. If you experience hangs when you
1531 suspend, try setting this to Y. Otherwise, say N.
1533 config APM_REAL_MODE_POWER_OFF
1534 bool "Use real mode APM BIOS call to power off"
1536 Use real mode APM BIOS calls to switch off the computer. This is
1537 a work-around for a number of buggy BIOSes. Switch this option on if
1538 your computer crashes instead of powering off properly.
1542 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1544 source "drivers/cpuidle/Kconfig"
1549 menu "Bus options (PCI etc.)"
1554 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1556 Find out whether you have a PCI motherboard. PCI is the name of a
1557 bus system, i.e. the way the CPU talks to the other stuff inside
1558 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1559 VESA. If you have PCI, say Y, otherwise N.
1562 prompt "PCI access mode"
1563 depends on X86_32 && PCI
1566 On PCI systems, the BIOS can be used to detect the PCI devices and
1567 determine their configuration. However, some old PCI motherboards
1568 have BIOS bugs and may crash if this is done. Also, some embedded
1569 PCI-based systems don't have any BIOS at all. Linux can also try to
1570 detect the PCI hardware directly without using the BIOS.
1572 With this option, you can specify how Linux should detect the
1573 PCI devices. If you choose "BIOS", the BIOS will be used,
1574 if you choose "Direct", the BIOS won't be used, and if you
1575 choose "MMConfig", then PCI Express MMCONFIG will be used.
1576 If you choose "Any", the kernel will try MMCONFIG, then the
1577 direct access method and falls back to the BIOS if that doesn't
1578 work. If unsure, go with the default, which is "Any".
1583 config PCI_GOMMCONFIG
1600 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1602 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1605 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1609 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1613 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1620 bool "Support mmconfig PCI config space access"
1621 depends on X86_64 && PCI && ACPI
1624 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1625 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1627 DMA remapping (DMAR) devices support enables independent address
1628 translations for Direct Memory Access (DMA) from devices.
1629 These DMA remapping devices are reported via ACPI tables
1630 and include PCI device scope covered by these DMA
1635 prompt "Support for Graphics workaround"
1638 Current Graphics drivers tend to use physical address
1639 for DMA and avoid using DMA APIs. Setting this config
1640 option permits the IOMMU driver to set a unity map for
1641 all the OS-visible memory. Hence the driver can continue
1642 to use physical addresses for DMA.
1644 config DMAR_FLOPPY_WA
1648 Floppy disk drivers are know to bypass DMA API calls
1649 thereby failing to work when IOMMU is enabled. This
1650 workaround will setup a 1:1 mapping for the first
1651 16M to make floppy (an ISA device) work.
1653 source "drivers/pci/pcie/Kconfig"
1655 source "drivers/pci/Kconfig"
1657 # x86_64 have no ISA slots, but do have ISA-style DMA.
1665 depends on !X86_VOYAGER
1667 Find out whether you have ISA slots on your motherboard. ISA is the
1668 name of a bus system, i.e. the way the CPU talks to the other stuff
1669 inside your box. Other bus systems are PCI, EISA, MicroChannel
1670 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1671 newer boards don't support it. If you have ISA, say Y, otherwise N.
1677 The Extended Industry Standard Architecture (EISA) bus was
1678 developed as an open alternative to the IBM MicroChannel bus.
1680 The EISA bus provided some of the features of the IBM MicroChannel
1681 bus while maintaining backward compatibility with cards made for
1682 the older ISA bus. The EISA bus saw limited use between 1988 and
1683 1995 when it was made obsolete by the PCI bus.
1685 Say Y here if you are building a kernel for an EISA-based machine.
1689 source "drivers/eisa/Kconfig"
1692 bool "MCA support" if !X86_VOYAGER
1693 default y if X86_VOYAGER
1695 MicroChannel Architecture is found in some IBM PS/2 machines and
1696 laptops. It is a bus system similar to PCI or ISA. See
1697 <file:Documentation/mca.txt> (and especially the web page given
1698 there) before attempting to build an MCA bus kernel.
1700 source "drivers/mca/Kconfig"
1703 tristate "NatSemi SCx200 support"
1704 depends on !X86_VOYAGER
1706 This provides basic support for National Semiconductor's
1707 (now AMD's) Geode processors. The driver probes for the
1708 PCI-IDs of several on-chip devices, so its a good dependency
1709 for other scx200_* drivers.
1711 If compiled as a module, the driver is named scx200.
1713 config SCx200HR_TIMER
1714 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1715 depends on SCx200 && GENERIC_TIME
1718 This driver provides a clocksource built upon the on-chip
1719 27MHz high-resolution timer. Its also a workaround for
1720 NSC Geode SC-1100's buggy TSC, which loses time when the
1721 processor goes idle (as is done by the scheduler). The
1722 other workaround is idle=poll boot option.
1724 config GEODE_MFGPT_TIMER
1726 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1727 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1729 This driver provides a clock event source based on the MFGPT
1730 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1731 MFGPTs have a better resolution and max interval than the
1732 generic PIT, and are suitable for use as high-res timers.
1735 bool "One Laptop Per Child support"
1738 Add support for detecting the unique features of the OLPC
1745 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1747 source "drivers/pcmcia/Kconfig"
1749 source "drivers/pci/hotplug/Kconfig"
1754 menu "Executable file formats / Emulations"
1756 source "fs/Kconfig.binfmt"
1758 config IA32_EMULATION
1759 bool "IA32 Emulation"
1761 select COMPAT_BINFMT_ELF
1763 Include code to run 32-bit programs under a 64-bit kernel. You should
1764 likely turn this on, unless you're 100% sure that you don't have any
1765 32-bit programs left.
1768 tristate "IA32 a.out support"
1769 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1771 Support old a.out binaries in the 32bit emulation.
1775 depends on IA32_EMULATION
1777 config COMPAT_FOR_U64_ALIGNMENT
1781 config SYSVIPC_COMPAT
1783 depends on X86_64 && COMPAT && SYSVIPC
1788 source "net/Kconfig"
1790 source "drivers/Kconfig"
1792 source "drivers/firmware/Kconfig"
1796 source "arch/x86/Kconfig.debug"
1798 source "security/Kconfig"
1800 source "crypto/Kconfig"
1802 source "arch/x86/kvm/Kconfig"
1804 source "lib/Kconfig"
projects / linux-2.6 / blob