2 mainmenu "Linux Kernel Configuration for x86"
6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
9 Say yes to build a 64-bit kernel - formerly known as x86_64
10 Say no to build a 32-bit kernel - formerly known as i386
21 select HAVE_UNSTABLE_SCHED_CLOCK
25 select HAVE_KRETPROBES
26 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
27 select HAVE_ARCH_KGDB if !X86_VOYAGER
33 default "arch/x86/configs/i386_defconfig"
39 default "arch/x86/configs/x86_64_defconfig"
42 config GENERIC_LOCKBREAK
48 config GENERIC_CMOS_UPDATE
51 config CLOCKSOURCE_WATCHDOG
54 config GENERIC_CLOCKEVENTS
57 config GENERIC_CLOCKEVENTS_BROADCAST
59 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
61 config LOCKDEP_SUPPORT
64 config STACKTRACE_SUPPORT
67 config HAVE_LATENCYTOP_SUPPORT
70 config FAST_CMPXCHG_LOCAL
83 config GENERIC_ISA_DMA
93 config GENERIC_HWEIGHT
99 config ARCH_MAY_HAVE_PC_FDC
102 config RWSEM_GENERIC_SPINLOCK
105 config RWSEM_XCHGADD_ALGORITHM
108 config ARCH_HAS_ILOG2_U32
111 config ARCH_HAS_ILOG2_U64
114 config ARCH_HAS_CPU_IDLE_WAIT
117 config GENERIC_CALIBRATE_DELAY
120 config GENERIC_TIME_VSYSCALL
124 config ARCH_HAS_CPU_RELAX
127 config ARCH_HAS_CACHE_LINE_SIZE
130 config HAVE_SETUP_PER_CPU_AREA
131 def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
133 config HAVE_CPUMASK_OF_CPU_MAP
136 config ARCH_HIBERNATION_POSSIBLE
138 depends on !SMP || !X86_VOYAGER
140 config ARCH_SUSPEND_POSSIBLE
142 depends on !X86_VOYAGER
148 config ARCH_POPULATES_NODE_MAP
155 config ARCH_SUPPORTS_AOUT
158 config ARCH_SUPPORTS_OPTIMIZED_INLINING
161 # Use the generic interrupt handling code in kernel/irq/:
162 config GENERIC_HARDIRQS
166 config GENERIC_IRQ_PROBE
170 config GENERIC_PENDING_IRQ
172 depends on GENERIC_HARDIRQS && SMP
177 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
182 depends on X86_32 && SMP
186 depends on X86_64 && SMP
191 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
194 config X86_BIOS_REBOOT
196 depends on !X86_VISWS && !X86_VOYAGER
199 config X86_TRAMPOLINE
201 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
206 source "init/Kconfig"
208 menu "Processor type and features"
210 source "kernel/time/Kconfig"
213 bool "Symmetric multi-processing support"
215 This enables support for systems with more than one CPU. If you have
216 a system with only one CPU, like most personal computers, say N. If
217 you have a system with more than one CPU, say Y.
219 If you say N here, the kernel will run on single and multiprocessor
220 machines, but will use only one CPU of a multiprocessor machine. If
221 you say Y here, the kernel will run on many, but not all,
222 singleprocessor machines. On a singleprocessor machine, the kernel
223 will run faster if you say N here.
225 Note that if you say Y here and choose architecture "586" or
226 "Pentium" under "Processor family", the kernel will not work on 486
227 architectures. Similarly, multiprocessor kernels for the "PPro"
228 architecture may not work on all Pentium based boards.
230 People using multiprocessor machines who say Y here should also say
231 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
232 Management" code will be disabled if you say Y here.
234 See also <file:Documentation/i386/IO-APIC.txt>,
235 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
236 <http://www.tldp.org/docs.html#howto>.
238 If you don't know what to do here, say N.
241 prompt "Subarchitecture Type"
247 Choose this option if your computer is a standard PC or compatible.
253 Select this for an AMD Elan processor.
255 Do not use this option for K6/Athlon/Opteron processors!
257 If unsure, choose "PC-compatible" instead.
261 depends on X86_32 && (SMP || BROKEN)
263 Voyager is an MCA-based 32-way capable SMP architecture proprietary
264 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
268 If you do not specifically know you have a Voyager based machine,
269 say N here, otherwise the kernel you build will not be bootable.
272 bool "NUMAQ (IBM/Sequent)"
273 depends on SMP && X86_32
276 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
277 multiquad box. This changes the way that processors are bootstrapped,
278 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
279 You will need a new lynxer.elf file to flash your firmware with - send
280 email to <Martin.Bligh@us.ibm.com>.
283 bool "Summit/EXA (IBM x440)"
284 depends on X86_32 && SMP
286 This option is needed for IBM systems that use the Summit/EXA chipset.
287 In particular, it is needed for the x440.
289 If you don't have one of these computers, you should say N here.
290 If you want to build a NUMA kernel, you must select ACPI.
293 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
294 depends on X86_32 && SMP
296 This option is needed for the systems that have more than 8 CPUs
297 and if the system is not of any sub-arch type above.
299 If you don't have such a system, you should say N here.
302 bool "SGI 320/540 (Visual Workstation)"
305 The SGI Visual Workstation series is an IA32-based workstation
306 based on SGI systems chips with some legacy PC hardware attached.
308 Say Y here to create a kernel to run on the SGI 320 or 540.
310 A kernel compiled for the Visual Workstation will not run on PCs
311 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
313 config X86_GENERICARCH
314 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
317 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
318 It is intended for a generic binary kernel.
319 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
322 bool "Support for Unisys ES7000 IA32 series"
323 depends on X86_32 && SMP
325 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
326 supposed to run on an IA32-based Unisys ES7000 system.
327 Only choose this option if you have such a system, otherwise you
331 bool "RDC R-321x SoC"
334 select X86_REBOOTFIXUPS
340 This option is needed for RDC R-321x system-on-chip, also known
342 If you don't have one of these chips, you should say N here.
345 bool "Support for ScaleMP vSMP"
349 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
350 supposed to run on these EM64T-based machines. Only choose this option
351 if you have one of these machines.
355 config SCHED_NO_NO_OMIT_FRAME_POINTER
357 prompt "Single-depth WCHAN output"
360 Calculate simpler /proc/<PID>/wchan values. If this option
361 is disabled then wchan values will recurse back to the
362 caller function. This provides more accurate wchan values,
363 at the expense of slightly more scheduling overhead.
365 If in doubt, say "Y".
367 menuconfig PARAVIRT_GUEST
368 bool "Paravirtualized guest support"
370 Say Y here to get to see options related to running Linux under
371 various hypervisors. This option alone does not add any kernel code.
373 If you say N, all options in this submenu will be skipped and disabled.
377 source "arch/x86/xen/Kconfig"
380 bool "VMI Guest support"
383 depends on !(X86_VISWS || X86_VOYAGER)
385 VMI provides a paravirtualized interface to the VMware ESX server
386 (it could be used by other hypervisors in theory too, but is not
387 at the moment), by linking the kernel to a GPL-ed ROM module
388 provided by the hypervisor.
391 bool "KVM paravirtualized clock"
393 depends on !(X86_VISWS || X86_VOYAGER)
395 Turning on this option will allow you to run a paravirtualized clock
396 when running over the KVM hypervisor. Instead of relying on a PIT
397 (or probably other) emulation by the underlying device model, the host
398 provides the guest with timing infrastructure such as time of day, and
402 bool "KVM Guest support"
404 depends on !(X86_VISWS || X86_VOYAGER)
406 This option enables various optimizations for running under the KVM
409 source "arch/x86/lguest/Kconfig"
412 bool "Enable paravirtualization code"
413 depends on !(X86_VISWS || X86_VOYAGER)
415 This changes the kernel so it can modify itself when it is run
416 under a hypervisor, potentially improving performance significantly
417 over full virtualization. However, when run without a hypervisor
418 the kernel is theoretically slower and slightly larger.
422 config MEMTEST_BOOTPARAM
423 bool "Memtest boot parameter"
427 This option adds a kernel parameter 'memtest', which allows memtest
428 to be disabled at boot. If this option is selected, memtest
429 functionality can be disabled with memtest=0 on the kernel
430 command line. The purpose of this option is to allow a single
431 kernel image to be distributed with memtest built in, but not
434 If you are unsure how to answer this question, answer Y.
436 config MEMTEST_BOOTPARAM_VALUE
437 int "Memtest boot parameter default value (0-4)"
438 depends on MEMTEST_BOOTPARAM
442 This option sets the default value for the kernel parameter
443 'memtest', which allows memtest to be disabled at boot. If this
444 option is set to 0 (zero), the memtest kernel parameter will
445 default to 0, disabling memtest at bootup. If this option is
446 set to 4, the memtest kernel parameter will default to 4,
447 enabling memtest at bootup, and use that as pattern number.
449 If you are unsure how to answer this question, answer 0.
453 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
456 config HAVE_ARCH_PARSE_SRAT
460 config X86_SUMMIT_NUMA
462 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
464 config X86_CYCLONE_TIMER
466 depends on X86_32 && X86_SUMMIT || 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.
554 # need this always selected by IOMMU for the VIA workaround
558 Support for software bounce buffers used on x86-64 systems
559 which don't have a hardware IOMMU (e.g. the current generation
560 of Intel's x86-64 CPUs). Using this PCI devices which can only
561 access 32-bits of memory can be used on systems with more than
562 3 GB of memory. If unsure, say Y.
565 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
568 int "Maximum number of CPUs (2-255)"
571 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
574 This allows you to specify the maximum number of CPUs which this
575 kernel will support. The maximum supported value is 255 and the
576 minimum value which makes sense is 2.
578 This is purely to save memory - each supported CPU adds
579 approximately eight kilobytes to the kernel image.
582 bool "SMT (Hyperthreading) scheduler support"
585 SMT scheduler support improves the CPU scheduler's decision making
586 when dealing with Intel Pentium 4 chips with HyperThreading at a
587 cost of slightly increased overhead in some places. If unsure say
592 prompt "Multi-core scheduler support"
595 Multi-core scheduler support improves the CPU scheduler's decision
596 making when dealing with multi-core CPU chips at a cost of slightly
597 increased overhead in some places. If unsure say N here.
599 source "kernel/Kconfig.preempt"
602 bool "Local APIC support on uniprocessors"
603 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
605 A local APIC (Advanced Programmable Interrupt Controller) is an
606 integrated interrupt controller in the CPU. If you have a single-CPU
607 system which has a processor with a local APIC, you can say Y here to
608 enable and use it. If you say Y here even though your machine doesn't
609 have a local APIC, then the kernel will still run with no slowdown at
610 all. The local APIC supports CPU-generated self-interrupts (timer,
611 performance counters), and the NMI watchdog which detects hard
615 bool "IO-APIC support on uniprocessors"
616 depends on X86_UP_APIC
618 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
619 SMP-capable replacement for PC-style interrupt controllers. Most
620 SMP systems and many recent uniprocessor systems have one.
622 If you have a single-CPU system with an IO-APIC, you can say Y here
623 to use it. If you say Y here even though your machine doesn't have
624 an IO-APIC, then the kernel will still run with no slowdown at all.
626 config X86_LOCAL_APIC
628 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
632 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
634 config X86_VISWS_APIC
636 depends on X86_32 && X86_VISWS
639 bool "Machine Check Exception"
640 depends on !X86_VOYAGER
642 Machine Check Exception support allows the processor to notify the
643 kernel if it detects a problem (e.g. overheating, component failure).
644 The action the kernel takes depends on the severity of the problem,
645 ranging from a warning message on the console, to halting the machine.
646 Your processor must be a Pentium or newer to support this - check the
647 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
648 have a design flaw which leads to false MCE events - hence MCE is
649 disabled on all P5 processors, unless explicitly enabled with "mce"
650 as a boot argument. Similarly, if MCE is built in and creates a
651 problem on some new non-standard machine, you can boot with "nomce"
652 to disable it. MCE support simply ignores non-MCE processors like
653 the 386 and 486, so nearly everyone can say Y here.
657 prompt "Intel MCE features"
658 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
660 Additional support for intel specific MCE features such as
665 prompt "AMD MCE features"
666 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
668 Additional support for AMD specific MCE features such as
669 the DRAM Error Threshold.
671 config X86_MCE_NONFATAL
672 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
673 depends on X86_32 && X86_MCE
675 Enabling this feature starts a timer that triggers every 5 seconds which
676 will look at the machine check registers to see if anything happened.
677 Non-fatal problems automatically get corrected (but still logged).
678 Disable this if you don't want to see these messages.
679 Seeing the messages this option prints out may be indicative of dying
680 or out-of-spec (ie, overclocked) hardware.
681 This option only does something on certain CPUs.
682 (AMD Athlon/Duron and Intel Pentium 4)
684 config X86_MCE_P4THERMAL
685 bool "check for P4 thermal throttling interrupt."
686 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
688 Enabling this feature will cause a message to be printed when the P4
689 enters thermal throttling.
692 bool "Enable VM86 support" if EMBEDDED
696 This option is required by programs like DOSEMU to run 16-bit legacy
697 code on X86 processors. It also may be needed by software like
698 XFree86 to initialize some video cards via BIOS. Disabling this
699 option saves about 6k.
702 tristate "Toshiba Laptop support"
705 This adds a driver to safely access the System Management Mode of
706 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
707 not work on models with a Phoenix BIOS. The System Management Mode
708 is used to set the BIOS and power saving options on Toshiba portables.
710 For information on utilities to make use of this driver see the
711 Toshiba Linux utilities web site at:
712 <http://www.buzzard.org.uk/toshiba/>.
714 Say Y if you intend to run this kernel on a Toshiba portable.
718 tristate "Dell laptop support"
720 This adds a driver to safely access the System Management Mode
721 of the CPU on the Dell Inspiron 8000. The System Management Mode
722 is used to read cpu temperature and cooling fan status and to
723 control the fans on the I8K portables.
725 This driver has been tested only on the Inspiron 8000 but it may
726 also work with other Dell laptops. You can force loading on other
727 models by passing the parameter `force=1' to the module. Use at
730 For information on utilities to make use of this driver see the
731 I8K Linux utilities web site at:
732 <http://people.debian.org/~dz/i8k/>
734 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
737 config X86_REBOOTFIXUPS
739 prompt "Enable X86 board specific fixups for reboot"
740 depends on X86_32 && X86
742 This enables chipset and/or board specific fixups to be done
743 in order to get reboot to work correctly. This is only needed on
744 some combinations of hardware and BIOS. The symptom, for which
745 this config is intended, is when reboot ends with a stalled/hung
748 Currently, the only fixup is for the Geode machines using
749 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
751 Say Y if you want to enable the fixup. Currently, it's safe to
752 enable this option even if you don't need it.
756 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
759 If you say Y here, you will be able to update the microcode on
760 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
761 Pentium III, Pentium 4, Xeon etc. You will obviously need the
762 actual microcode binary data itself which is not shipped with the
765 For latest news and information on obtaining all the required
766 ingredients for this driver, check:
767 <http://www.urbanmyth.org/microcode/>.
769 To compile this driver as a module, choose M here: the
770 module will be called microcode.
772 config MICROCODE_OLD_INTERFACE
777 tristate "/dev/cpu/*/msr - Model-specific register support"
779 This device gives privileged processes access to the x86
780 Model-Specific Registers (MSRs). It is a character device with
781 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
782 MSR accesses are directed to a specific CPU on multi-processor
786 tristate "/dev/cpu/*/cpuid - CPU information support"
788 This device gives processes access to the x86 CPUID instruction to
789 be executed on a specific processor. It is a character device
790 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
794 prompt "High Memory Support"
795 default HIGHMEM4G if !X86_NUMAQ
796 default HIGHMEM64G if X86_NUMAQ
801 depends on !X86_NUMAQ
803 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
804 However, the address space of 32-bit x86 processors is only 4
805 Gigabytes large. That means that, if you have a large amount of
806 physical memory, not all of it can be "permanently mapped" by the
807 kernel. The physical memory that's not permanently mapped is called
810 If you are compiling a kernel which will never run on a machine with
811 more than 1 Gigabyte total physical RAM, answer "off" here (default
812 choice and suitable for most users). This will result in a "3GB/1GB"
813 split: 3GB are mapped so that each process sees a 3GB virtual memory
814 space and the remaining part of the 4GB virtual memory space is used
815 by the kernel to permanently map as much physical memory as
818 If the machine has between 1 and 4 Gigabytes physical RAM, then
821 If more than 4 Gigabytes is used then answer "64GB" here. This
822 selection turns Intel PAE (Physical Address Extension) mode on.
823 PAE implements 3-level paging on IA32 processors. PAE is fully
824 supported by Linux, PAE mode is implemented on all recent Intel
825 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
826 then the kernel will not boot on CPUs that don't support PAE!
828 The actual amount of total physical memory will either be
829 auto detected or can be forced by using a kernel command line option
830 such as "mem=256M". (Try "man bootparam" or see the documentation of
831 your boot loader (lilo or loadlin) about how to pass options to the
832 kernel at boot time.)
834 If unsure, say "off".
838 depends on !X86_NUMAQ
840 Select this if you have a 32-bit processor and between 1 and 4
841 gigabytes of physical RAM.
845 depends on !M386 && !M486
848 Select this if you have a 32-bit processor and more than 4
849 gigabytes of physical RAM.
854 depends on EXPERIMENTAL
855 prompt "Memory split" if EMBEDDED
859 Select the desired split between kernel and user memory.
861 If the address range available to the kernel is less than the
862 physical memory installed, the remaining memory will be available
863 as "high memory". Accessing high memory is a little more costly
864 than low memory, as it needs to be mapped into the kernel first.
865 Note that increasing the kernel address space limits the range
866 available to user programs, making the address space there
867 tighter. Selecting anything other than the default 3G/1G split
868 will also likely make your kernel incompatible with binary-only
871 If you are not absolutely sure what you are doing, leave this
875 bool "3G/1G user/kernel split"
876 config VMSPLIT_3G_OPT
878 bool "3G/1G user/kernel split (for full 1G low memory)"
880 bool "2G/2G user/kernel split"
881 config VMSPLIT_2G_OPT
883 bool "2G/2G user/kernel split (for full 2G low memory)"
885 bool "1G/3G user/kernel split"
890 default 0xB0000000 if VMSPLIT_3G_OPT
891 default 0x80000000 if VMSPLIT_2G
892 default 0x78000000 if VMSPLIT_2G_OPT
893 default 0x40000000 if VMSPLIT_1G
899 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
903 prompt "PAE (Physical Address Extension) Support"
904 depends on X86_32 && !HIGHMEM4G
905 select RESOURCES_64BIT
907 PAE is required for NX support, and furthermore enables
908 larger swapspace support for non-overcommit purposes. It
909 has the cost of more pagetable lookup overhead, and also
910 consumes more pagetable space per process.
912 # Common NUMA Features
914 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
916 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
918 default y if (X86_NUMAQ || X86_SUMMIT)
920 Enable NUMA (Non Uniform Memory Access) support.
921 The kernel will try to allocate memory used by a CPU on the
922 local memory controller of the CPU and add some more
923 NUMA awareness to the kernel.
925 For i386 this is currently highly experimental and should be only
926 used for kernel development. It might also cause boot failures.
927 For x86_64 this is recommended on all multiprocessor Opteron systems.
928 If the system is EM64T, you should say N unless your system is
931 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
932 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
936 prompt "Old style AMD Opteron NUMA detection"
937 depends on X86_64 && NUMA && PCI
939 Enable K8 NUMA node topology detection. You should say Y here if
940 you have a multi processor AMD K8 system. This uses an old
941 method to read the NUMA configuration directly from the builtin
942 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
943 instead, which also takes priority if both are compiled in.
945 config X86_64_ACPI_NUMA
947 prompt "ACPI NUMA detection"
948 depends on X86_64 && NUMA && ACPI && PCI
951 Enable ACPI SRAT based node topology detection.
953 # Some NUMA nodes have memory ranges that span
954 # other nodes. Even though a pfn is valid and
955 # between a node's start and end pfns, it may not
956 # reside on that node. See memmap_init_zone()
958 config NODES_SPAN_OTHER_NODES
960 depends on X86_64_ACPI_NUMA
963 bool "NUMA emulation"
964 depends on X86_64 && NUMA
966 Enable NUMA emulation. A flat machine will be split
967 into virtual nodes when booted with "numa=fake=N", where N is the
968 number of nodes. This is only useful for debugging.
971 int "Max num nodes shift(1-15)"
973 default "6" if X86_64
974 default "4" if X86_NUMAQ
976 depends on NEED_MULTIPLE_NODES
978 config HAVE_ARCH_BOOTMEM_NODE
980 depends on X86_32 && NUMA
982 config ARCH_HAVE_MEMORY_PRESENT
984 depends on X86_32 && DISCONTIGMEM
986 config NEED_NODE_MEMMAP_SIZE
988 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
990 config HAVE_ARCH_ALLOC_REMAP
992 depends on X86_32 && NUMA
994 config ARCH_FLATMEM_ENABLE
996 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
998 config ARCH_DISCONTIGMEM_ENABLE
1000 depends on NUMA && X86_32
1002 config ARCH_DISCONTIGMEM_DEFAULT
1004 depends on NUMA && X86_32
1006 config ARCH_SPARSEMEM_DEFAULT
1010 config ARCH_SPARSEMEM_ENABLE
1012 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1013 select SPARSEMEM_STATIC if X86_32
1014 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1016 config ARCH_SELECT_MEMORY_MODEL
1018 depends on ARCH_SPARSEMEM_ENABLE
1020 config ARCH_MEMORY_PROBE
1022 depends on MEMORY_HOTPLUG
1027 bool "Allocate 3rd-level pagetables from highmem"
1028 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1030 The VM uses one page table entry for each page of physical memory.
1031 For systems with a lot of RAM, this can be wasteful of precious
1032 low memory. Setting this option will put user-space page table
1033 entries in high memory.
1035 config MATH_EMULATION
1037 prompt "Math emulation" if X86_32
1039 Linux can emulate a math coprocessor (used for floating point
1040 operations) if you don't have one. 486DX and Pentium processors have
1041 a math coprocessor built in, 486SX and 386 do not, unless you added
1042 a 487DX or 387, respectively. (The messages during boot time can
1043 give you some hints here ["man dmesg"].) Everyone needs either a
1044 coprocessor or this emulation.
1046 If you don't have a math coprocessor, you need to say Y here; if you
1047 say Y here even though you have a coprocessor, the coprocessor will
1048 be used nevertheless. (This behavior can be changed with the kernel
1049 command line option "no387", which comes handy if your coprocessor
1050 is broken. Try "man bootparam" or see the documentation of your boot
1051 loader (lilo or loadlin) about how to pass options to the kernel at
1052 boot time.) This means that it is a good idea to say Y here if you
1053 intend to use this kernel on different machines.
1055 More information about the internals of the Linux math coprocessor
1056 emulation can be found in <file:arch/x86/math-emu/README>.
1058 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1059 kernel, it won't hurt.
1062 bool "MTRR (Memory Type Range Register) support"
1064 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1065 the Memory Type Range Registers (MTRRs) may be used to control
1066 processor access to memory ranges. This is most useful if you have
1067 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1068 allows bus write transfers to be combined into a larger transfer
1069 before bursting over the PCI/AGP bus. This can increase performance
1070 of image write operations 2.5 times or more. Saying Y here creates a
1071 /proc/mtrr file which may be used to manipulate your processor's
1072 MTRRs. Typically the X server should use this.
1074 This code has a reasonably generic interface so that similar
1075 control registers on other processors can be easily supported
1078 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1079 Registers (ARRs) which provide a similar functionality to MTRRs. For
1080 these, the ARRs are used to emulate the MTRRs.
1081 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1082 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1083 write-combining. All of these processors are supported by this code
1084 and it makes sense to say Y here if you have one of them.
1086 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1087 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1088 can lead to all sorts of problems, so it's good to say Y here.
1090 You can safely say Y even if your machine doesn't have MTRRs, you'll
1091 just add about 9 KB to your kernel.
1093 See <file:Documentation/mtrr.txt> for more information.
1095 config MTRR_SANITIZER
1097 prompt "MTRR cleanup support"
1100 Convert MTRR layout from continuous to discrete, so some X driver
1101 could add WB entries.
1103 Say N here if you see bootup problems (boot crash, boot hang,
1104 spontaneous reboots).
1106 Could be disabled with disable_mtrr_cleanup. Also mtrr_chunk_size
1107 could be used to send largest mtrr entry size for continuous block
1108 to hold holes (aka. UC entries)
1112 config MTRR_SANITIZER_ENABLE_DEFAULT
1113 int "MTRR cleanup enable value (0-1)"
1116 depends on MTRR_SANITIZER
1118 Enable mtrr cleanup default value
1120 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1121 int "MTRR cleanup spare reg num (0-7)"
1124 depends on MTRR_SANITIZER
1126 mtrr cleanup spare entries default, it can be changed via
1131 prompt "x86 PAT support"
1134 Use PAT attributes to setup page level cache control.
1136 PATs are the modern equivalents of MTRRs and are much more
1137 flexible than MTRRs.
1139 Say N here if you see bootup problems (boot crash, boot hang,
1140 spontaneous reboots) or a non-working video driver.
1146 prompt "EFI runtime service support"
1149 This enables the kernel to use EFI runtime services that are
1150 available (such as the EFI variable services).
1152 This option is only useful on systems that have EFI firmware.
1153 In addition, you should use the latest ELILO loader available
1154 at <http://elilo.sourceforge.net> in order to take advantage
1155 of EFI runtime services. However, even with this option, the
1156 resultant kernel should continue to boot on existing non-EFI
1161 prompt "Enable kernel irq balancing"
1162 depends on X86_32 && SMP && X86_IO_APIC
1164 The default yes will allow the kernel to do irq load balancing.
1165 Saying no will keep the kernel from doing irq load balancing.
1169 prompt "Enable seccomp to safely compute untrusted bytecode"
1172 This kernel feature is useful for number crunching applications
1173 that may need to compute untrusted bytecode during their
1174 execution. By using pipes or other transports made available to
1175 the process as file descriptors supporting the read/write
1176 syscalls, it's possible to isolate those applications in
1177 their own address space using seccomp. Once seccomp is
1178 enabled via /proc/<pid>/seccomp, it cannot be disabled
1179 and the task is only allowed to execute a few safe syscalls
1180 defined by each seccomp mode.
1182 If unsure, say Y. Only embedded should say N here.
1184 config CC_STACKPROTECTOR
1185 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1186 depends on X86_64 && EXPERIMENTAL && BROKEN
1188 This option turns on the -fstack-protector GCC feature. This
1189 feature puts, at the beginning of critical functions, a canary
1190 value on the stack just before the return address, and validates
1191 the value just before actually returning. Stack based buffer
1192 overflows (that need to overwrite this return address) now also
1193 overwrite the canary, which gets detected and the attack is then
1194 neutralized via a kernel panic.
1196 This feature requires gcc version 4.2 or above, or a distribution
1197 gcc with the feature backported. Older versions are automatically
1198 detected and for those versions, this configuration option is ignored.
1200 config CC_STACKPROTECTOR_ALL
1201 bool "Use stack-protector for all functions"
1202 depends on CC_STACKPROTECTOR
1204 Normally, GCC only inserts the canary value protection for
1205 functions that use large-ish on-stack buffers. By enabling
1206 this option, GCC will be asked to do this for ALL functions.
1208 source kernel/Kconfig.hz
1211 bool "kexec system call"
1212 depends on X86_BIOS_REBOOT
1214 kexec is a system call that implements the ability to shutdown your
1215 current kernel, and to start another kernel. It is like a reboot
1216 but it is independent of the system firmware. And like a reboot
1217 you can start any kernel with it, not just Linux.
1219 The name comes from the similarity to the exec system call.
1221 It is an ongoing process to be certain the hardware in a machine
1222 is properly shutdown, so do not be surprised if this code does not
1223 initially work for you. It may help to enable device hotplugging
1224 support. As of this writing the exact hardware interface is
1225 strongly in flux, so no good recommendation can be made.
1228 bool "kernel crash dumps (EXPERIMENTAL)"
1229 depends on EXPERIMENTAL
1230 depends on X86_64 || (X86_32 && HIGHMEM)
1232 Generate crash dump after being started by kexec.
1233 This should be normally only set in special crash dump kernels
1234 which are loaded in the main kernel with kexec-tools into
1235 a specially reserved region and then later executed after
1236 a crash by kdump/kexec. The crash dump kernel must be compiled
1237 to a memory address not used by the main kernel or BIOS using
1238 PHYSICAL_START, or it must be built as a relocatable image
1239 (CONFIG_RELOCATABLE=y).
1240 For more details see Documentation/kdump/kdump.txt
1242 config PHYSICAL_START
1243 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1244 default "0x1000000" if X86_NUMAQ
1245 default "0x200000" if X86_64
1248 This gives the physical address where the kernel is loaded.
1250 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1251 bzImage will decompress itself to above physical address and
1252 run from there. Otherwise, bzImage will run from the address where
1253 it has been loaded by the boot loader and will ignore above physical
1256 In normal kdump cases one does not have to set/change this option
1257 as now bzImage can be compiled as a completely relocatable image
1258 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1259 address. This option is mainly useful for the folks who don't want
1260 to use a bzImage for capturing the crash dump and want to use a
1261 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1262 to be specifically compiled to run from a specific memory area
1263 (normally a reserved region) and this option comes handy.
1265 So if you are using bzImage for capturing the crash dump, leave
1266 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1267 Otherwise if you plan to use vmlinux for capturing the crash dump
1268 change this value to start of the reserved region (Typically 16MB
1269 0x1000000). In other words, it can be set based on the "X" value as
1270 specified in the "crashkernel=YM@XM" command line boot parameter
1271 passed to the panic-ed kernel. Typically this parameter is set as
1272 crashkernel=64M@16M. Please take a look at
1273 Documentation/kdump/kdump.txt for more details about crash dumps.
1275 Usage of bzImage for capturing the crash dump is recommended as
1276 one does not have to build two kernels. Same kernel can be used
1277 as production kernel and capture kernel. Above option should have
1278 gone away after relocatable bzImage support is introduced. But it
1279 is present because there are users out there who continue to use
1280 vmlinux for dump capture. This option should go away down the
1283 Don't change this unless you know what you are doing.
1286 bool "Build a relocatable kernel (EXPERIMENTAL)"
1287 depends on EXPERIMENTAL
1289 This builds a kernel image that retains relocation information
1290 so it can be loaded someplace besides the default 1MB.
1291 The relocations tend to make the kernel binary about 10% larger,
1292 but are discarded at runtime.
1294 One use is for the kexec on panic case where the recovery kernel
1295 must live at a different physical address than the primary
1298 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1299 it has been loaded at and the compile time physical address
1300 (CONFIG_PHYSICAL_START) is ignored.
1302 config PHYSICAL_ALIGN
1304 prompt "Alignment value to which kernel should be aligned" if X86_32
1305 default "0x100000" if X86_32
1306 default "0x200000" if X86_64
1307 range 0x2000 0x400000
1309 This value puts the alignment restrictions on physical address
1310 where kernel is loaded and run from. Kernel is compiled for an
1311 address which meets above alignment restriction.
1313 If bootloader loads the kernel at a non-aligned address and
1314 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1315 address aligned to above value and run from there.
1317 If bootloader loads the kernel at a non-aligned address and
1318 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1319 load address and decompress itself to the address it has been
1320 compiled for and run from there. The address for which kernel is
1321 compiled already meets above alignment restrictions. Hence the
1322 end result is that kernel runs from a physical address meeting
1323 above alignment restrictions.
1325 Don't change this unless you know what you are doing.
1328 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1329 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1331 Say Y here to experiment with turning CPUs off and on, and to
1332 enable suspend on SMP systems. CPUs can be controlled through
1333 /sys/devices/system/cpu.
1334 Say N if you want to disable CPU hotplug and don't need to
1339 prompt "Compat VDSO support"
1340 depends on X86_32 || IA32_EMULATION
1342 Map the 32-bit VDSO to the predictable old-style address too.
1344 Say N here if you are running a sufficiently recent glibc
1345 version (2.3.3 or later), to remove the high-mapped
1346 VDSO mapping and to exclusively use the randomized VDSO.
1352 config ARCH_ENABLE_MEMORY_HOTPLUG
1354 depends on X86_64 || (X86_32 && HIGHMEM)
1356 config HAVE_ARCH_EARLY_PFN_TO_NID
1360 menu "Power management options"
1361 depends on !X86_VOYAGER
1363 config ARCH_HIBERNATION_HEADER
1365 depends on X86_64 && HIBERNATION
1367 source "kernel/power/Kconfig"
1369 source "drivers/acpi/Kconfig"
1374 depends on APM || APM_MODULE
1377 tristate "APM (Advanced Power Management) BIOS support"
1378 depends on X86_32 && PM_SLEEP && !X86_VISWS
1380 APM is a BIOS specification for saving power using several different
1381 techniques. This is mostly useful for battery powered laptops with
1382 APM compliant BIOSes. If you say Y here, the system time will be
1383 reset after a RESUME operation, the /proc/apm device will provide
1384 battery status information, and user-space programs will receive
1385 notification of APM "events" (e.g. battery status change).
1387 If you select "Y" here, you can disable actual use of the APM
1388 BIOS by passing the "apm=off" option to the kernel at boot time.
1390 Note that the APM support is almost completely disabled for
1391 machines with more than one CPU.
1393 In order to use APM, you will need supporting software. For location
1394 and more information, read <file:Documentation/power/pm.txt> and the
1395 Battery Powered Linux mini-HOWTO, available from
1396 <http://www.tldp.org/docs.html#howto>.
1398 This driver does not spin down disk drives (see the hdparm(8)
1399 manpage ("man 8 hdparm") for that), and it doesn't turn off
1400 VESA-compliant "green" monitors.
1402 This driver does not support the TI 4000M TravelMate and the ACER
1403 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1404 desktop machines also don't have compliant BIOSes, and this driver
1405 may cause those machines to panic during the boot phase.
1407 Generally, if you don't have a battery in your machine, there isn't
1408 much point in using this driver and you should say N. If you get
1409 random kernel OOPSes or reboots that don't seem to be related to
1410 anything, try disabling/enabling this option (or disabling/enabling
1413 Some other things you should try when experiencing seemingly random,
1416 1) make sure that you have enough swap space and that it is
1418 2) pass the "no-hlt" option to the kernel
1419 3) switch on floating point emulation in the kernel and pass
1420 the "no387" option to the kernel
1421 4) pass the "floppy=nodma" option to the kernel
1422 5) pass the "mem=4M" option to the kernel (thereby disabling
1423 all but the first 4 MB of RAM)
1424 6) make sure that the CPU is not over clocked.
1425 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1426 8) disable the cache from your BIOS settings
1427 9) install a fan for the video card or exchange video RAM
1428 10) install a better fan for the CPU
1429 11) exchange RAM chips
1430 12) exchange the motherboard.
1432 To compile this driver as a module, choose M here: the
1433 module will be called apm.
1437 config APM_IGNORE_USER_SUSPEND
1438 bool "Ignore USER SUSPEND"
1440 This option will ignore USER SUSPEND requests. On machines with a
1441 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1442 series notebooks, it is necessary to say Y because of a BIOS bug.
1444 config APM_DO_ENABLE
1445 bool "Enable PM at boot time"
1447 Enable APM features at boot time. From page 36 of the APM BIOS
1448 specification: "When disabled, the APM BIOS does not automatically
1449 power manage devices, enter the Standby State, enter the Suspend
1450 State, or take power saving steps in response to CPU Idle calls."
1451 This driver will make CPU Idle calls when Linux is idle (unless this
1452 feature is turned off -- see "Do CPU IDLE calls", below). This
1453 should always save battery power, but more complicated APM features
1454 will be dependent on your BIOS implementation. You may need to turn
1455 this option off if your computer hangs at boot time when using APM
1456 support, or if it beeps continuously instead of suspending. Turn
1457 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1458 T400CDT. This is off by default since most machines do fine without
1462 bool "Make CPU Idle calls when idle"
1464 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1465 On some machines, this can activate improved power savings, such as
1466 a slowed CPU clock rate, when the machine is idle. These idle calls
1467 are made after the idle loop has run for some length of time (e.g.,
1468 333 mS). On some machines, this will cause a hang at boot time or
1469 whenever the CPU becomes idle. (On machines with more than one CPU,
1470 this option does nothing.)
1472 config APM_DISPLAY_BLANK
1473 bool "Enable console blanking using APM"
1475 Enable console blanking using the APM. Some laptops can use this to
1476 turn off the LCD backlight when the screen blanker of the Linux
1477 virtual console blanks the screen. Note that this is only used by
1478 the virtual console screen blanker, and won't turn off the backlight
1479 when using the X Window system. This also doesn't have anything to
1480 do with your VESA-compliant power-saving monitor. Further, this
1481 option doesn't work for all laptops -- it might not turn off your
1482 backlight at all, or it might print a lot of errors to the console,
1483 especially if you are using gpm.
1485 config APM_ALLOW_INTS
1486 bool "Allow interrupts during APM BIOS calls"
1488 Normally we disable external interrupts while we are making calls to
1489 the APM BIOS as a measure to lessen the effects of a badly behaving
1490 BIOS implementation. The BIOS should reenable interrupts if it
1491 needs to. Unfortunately, some BIOSes do not -- especially those in
1492 many of the newer IBM Thinkpads. If you experience hangs when you
1493 suspend, try setting this to Y. Otherwise, say N.
1495 config APM_REAL_MODE_POWER_OFF
1496 bool "Use real mode APM BIOS call to power off"
1498 Use real mode APM BIOS calls to switch off the computer. This is
1499 a work-around for a number of buggy BIOSes. Switch this option on if
1500 your computer crashes instead of powering off properly.
1504 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1506 source "drivers/cpuidle/Kconfig"
1511 menu "Bus options (PCI etc.)"
1514 bool "PCI support" if !X86_VISWS && !X86_VSMP
1515 depends on !X86_VOYAGER
1517 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1519 Find out whether you have a PCI motherboard. PCI is the name of a
1520 bus system, i.e. the way the CPU talks to the other stuff inside
1521 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1522 VESA. If you have PCI, say Y, otherwise N.
1525 prompt "PCI access mode"
1526 depends on X86_32 && PCI && !X86_VISWS
1529 On PCI systems, the BIOS can be used to detect the PCI devices and
1530 determine their configuration. However, some old PCI motherboards
1531 have BIOS bugs and may crash if this is done. Also, some embedded
1532 PCI-based systems don't have any BIOS at all. Linux can also try to
1533 detect the PCI hardware directly without using the BIOS.
1535 With this option, you can specify how Linux should detect the
1536 PCI devices. If you choose "BIOS", the BIOS will be used,
1537 if you choose "Direct", the BIOS won't be used, and if you
1538 choose "MMConfig", then PCI Express MMCONFIG will be used.
1539 If you choose "Any", the kernel will try MMCONFIG, then the
1540 direct access method and falls back to the BIOS if that doesn't
1541 work. If unsure, go with the default, which is "Any".
1546 config PCI_GOMMCONFIG
1563 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1565 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1568 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
1572 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1576 depends on PCI && PCI_GOOLPC
1584 bool "Support mmconfig PCI config space access"
1585 depends on X86_64 && PCI && ACPI
1588 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1589 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1591 DMA remapping (DMAR) devices support enables independent address
1592 translations for Direct Memory Access (DMA) from devices.
1593 These DMA remapping devices are reported via ACPI tables
1594 and include PCI device scope covered by these DMA
1599 prompt "Support for Graphics workaround"
1602 Current Graphics drivers tend to use physical address
1603 for DMA and avoid using DMA APIs. Setting this config
1604 option permits the IOMMU driver to set a unity map for
1605 all the OS-visible memory. Hence the driver can continue
1606 to use physical addresses for DMA.
1608 config DMAR_FLOPPY_WA
1612 Floppy disk drivers are know to bypass DMA API calls
1613 thereby failing to work when IOMMU is enabled. This
1614 workaround will setup a 1:1 mapping for the first
1615 16M to make floppy (an ISA device) work.
1617 source "drivers/pci/pcie/Kconfig"
1619 source "drivers/pci/Kconfig"
1621 # x86_64 have no ISA slots, but do have ISA-style DMA.
1629 depends on !(X86_VOYAGER || X86_VISWS)
1631 Find out whether you have ISA slots on your motherboard. ISA is the
1632 name of a bus system, i.e. the way the CPU talks to the other stuff
1633 inside your box. Other bus systems are PCI, EISA, MicroChannel
1634 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1635 newer boards don't support it. If you have ISA, say Y, otherwise N.
1641 The Extended Industry Standard Architecture (EISA) bus was
1642 developed as an open alternative to the IBM MicroChannel bus.
1644 The EISA bus provided some of the features of the IBM MicroChannel
1645 bus while maintaining backward compatibility with cards made for
1646 the older ISA bus. The EISA bus saw limited use between 1988 and
1647 1995 when it was made obsolete by the PCI bus.
1649 Say Y here if you are building a kernel for an EISA-based machine.
1653 source "drivers/eisa/Kconfig"
1656 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1657 default y if X86_VOYAGER
1659 MicroChannel Architecture is found in some IBM PS/2 machines and
1660 laptops. It is a bus system similar to PCI or ISA. See
1661 <file:Documentation/mca.txt> (and especially the web page given
1662 there) before attempting to build an MCA bus kernel.
1664 source "drivers/mca/Kconfig"
1667 tristate "NatSemi SCx200 support"
1668 depends on !X86_VOYAGER
1670 This provides basic support for National Semiconductor's
1671 (now AMD's) Geode processors. The driver probes for the
1672 PCI-IDs of several on-chip devices, so its a good dependency
1673 for other scx200_* drivers.
1675 If compiled as a module, the driver is named scx200.
1677 config SCx200HR_TIMER
1678 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1679 depends on SCx200 && GENERIC_TIME
1682 This driver provides a clocksource built upon the on-chip
1683 27MHz high-resolution timer. Its also a workaround for
1684 NSC Geode SC-1100's buggy TSC, which loses time when the
1685 processor goes idle (as is done by the scheduler). The
1686 other workaround is idle=poll boot option.
1688 config GEODE_MFGPT_TIMER
1690 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1691 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1693 This driver provides a clock event source based on the MFGPT
1694 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1695 MFGPTs have a better resolution and max interval than the
1696 generic PIT, and are suitable for use as high-res timers.
1699 bool "One Laptop Per Child support"
1702 Add support for detecting the unique features of the OLPC
1709 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1711 source "drivers/pcmcia/Kconfig"
1713 source "drivers/pci/hotplug/Kconfig"
1718 menu "Executable file formats / Emulations"
1720 source "fs/Kconfig.binfmt"
1722 config IA32_EMULATION
1723 bool "IA32 Emulation"
1725 select COMPAT_BINFMT_ELF
1727 Include code to run 32-bit programs under a 64-bit kernel. You should
1728 likely turn this on, unless you're 100% sure that you don't have any
1729 32-bit programs left.
1732 tristate "IA32 a.out support"
1733 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1735 Support old a.out binaries in the 32bit emulation.
1739 depends on IA32_EMULATION
1741 config COMPAT_FOR_U64_ALIGNMENT
1745 config SYSVIPC_COMPAT
1747 depends on X86_64 && COMPAT && SYSVIPC
1752 source "net/Kconfig"
1754 source "drivers/Kconfig"
1756 source "drivers/firmware/Kconfig"
1760 source "arch/x86/Kconfig.debug"
1762 source "security/Kconfig"
1764 source "crypto/Kconfig"
1766 source "arch/x86/kvm/Kconfig"
1768 source "lib/Kconfig"
git.openpandora.org / pandora-kernel.git / blob