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_DYNAMIC_FTRACE
28 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
29 select HAVE_ARCH_KGDB if !X86_VOYAGER
33 default "arch/x86/configs/i386_defconfig" if X86_32
34 default "arch/x86/configs/x86_64_defconfig" if X86_64
37 config GENERIC_LOCKBREAK
43 config GENERIC_CMOS_UPDATE
46 config CLOCKSOURCE_WATCHDOG
49 config GENERIC_CLOCKEVENTS
52 config GENERIC_CLOCKEVENTS_BROADCAST
54 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
56 config LOCKDEP_SUPPORT
59 config STACKTRACE_SUPPORT
62 config HAVE_LATENCYTOP_SUPPORT
65 config FAST_CMPXCHG_LOCAL
78 config GENERIC_ISA_DMA
88 config GENERIC_HWEIGHT
94 config ARCH_MAY_HAVE_PC_FDC
97 config RWSEM_GENERIC_SPINLOCK
100 config RWSEM_XCHGADD_ALGORITHM
103 config ARCH_HAS_ILOG2_U32
106 config ARCH_HAS_ILOG2_U64
109 config ARCH_HAS_CPU_IDLE_WAIT
112 config GENERIC_CALIBRATE_DELAY
115 config GENERIC_TIME_VSYSCALL
119 config ARCH_HAS_CPU_RELAX
122 config ARCH_HAS_CACHE_LINE_SIZE
125 config HAVE_SETUP_PER_CPU_AREA
126 def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER)
128 config HAVE_CPUMASK_OF_CPU_MAP
131 config ARCH_HIBERNATION_POSSIBLE
133 depends on !SMP || !X86_VOYAGER
135 config ARCH_SUSPEND_POSSIBLE
137 depends on !X86_VOYAGER
143 config ARCH_POPULATES_NODE_MAP
150 config ARCH_SUPPORTS_AOUT
153 config ARCH_SUPPORTS_OPTIMIZED_INLINING
156 # Use the generic interrupt handling code in kernel/irq/:
157 config GENERIC_HARDIRQS
161 config GENERIC_IRQ_PROBE
165 config GENERIC_PENDING_IRQ
167 depends on GENERIC_HARDIRQS && SMP
172 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
177 depends on X86_32 && SMP
181 depends on X86_64 && SMP
186 depends on (X86_32 && !X86_VOYAGER) || X86_64
189 config X86_BIOS_REBOOT
191 depends on !X86_VOYAGER
194 config X86_TRAMPOLINE
196 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
201 source "init/Kconfig"
203 menu "Processor type and features"
205 source "kernel/time/Kconfig"
208 bool "Symmetric multi-processing support"
210 This enables support for systems with more than one CPU. If you have
211 a system with only one CPU, like most personal computers, say N. If
212 you have a system with more than one CPU, say Y.
214 If you say N here, the kernel will run on single and multiprocessor
215 machines, but will use only one CPU of a multiprocessor machine. If
216 you say Y here, the kernel will run on many, but not all,
217 singleprocessor machines. On a singleprocessor machine, the kernel
218 will run faster if you say N here.
220 Note that if you say Y here and choose architecture "586" or
221 "Pentium" under "Processor family", the kernel will not work on 486
222 architectures. Similarly, multiprocessor kernels for the "PPro"
223 architecture may not work on all Pentium based boards.
225 People using multiprocessor machines who say Y here should also say
226 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
227 Management" code will be disabled if you say Y here.
229 See also <file:Documentation/i386/IO-APIC.txt>,
230 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
231 <http://www.tldp.org/docs.html#howto>.
233 If you don't know what to do here, say N.
235 config X86_FIND_SMP_CONFIG
237 depends on X86_MPPARSE || X86_VOYAGER
242 bool "Enable MPS table"
243 depends on X86_LOCAL_APIC
245 For old smp systems that do not have proper acpi support. Newer systems
246 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
252 depends on X86_LOCAL_APIC
256 prompt "Subarchitecture Type"
262 Choose this option if your computer is a standard PC or compatible.
268 Select this for an AMD Elan processor.
270 Do not use this option for K6/Athlon/Opteron processors!
272 If unsure, choose "PC-compatible" instead.
276 depends on X86_32 && (SMP || BROKEN) && !PCI
278 Voyager is an MCA-based 32-way capable SMP architecture proprietary
279 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
283 If you do not specifically know you have a Voyager based machine,
284 say N here, otherwise the kernel you build will not be bootable.
286 config X86_GENERICARCH
287 bool "Generic architecture"
290 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
291 subarchitectures. It is intended for a generic binary kernel.
292 if you select them all, kernel will probe it one by one. and will
298 bool "NUMAQ (IBM/Sequent)"
299 depends on SMP && X86_32 && PCI && X86_MPPARSE
302 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
303 NUMA multiquad box. This changes the way that processors are
304 bootstrapped, and uses Clustered Logical APIC addressing mode instead
305 of Flat Logical. You will need a new lynxer.elf file to flash your
306 firmware with - send email to <Martin.Bligh@us.ibm.com>.
309 bool "Summit/EXA (IBM x440)"
310 depends on X86_32 && SMP
312 This option is needed for IBM systems that use the Summit/EXA chipset.
313 In particular, it is needed for the x440.
316 bool "Support for Unisys ES7000 IA32 series"
317 depends on X86_32 && SMP
319 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
320 supposed to run on an IA32-based Unisys ES7000 system.
323 bool "Support for big SMP systems with more than 8 CPUs"
324 depends on X86_32 && SMP
326 This option is needed for the systems that have more than 8 CPUs
327 and if the system is not of any sub-arch type above.
332 bool "RDC R-321x SoC"
335 select X86_REBOOTFIXUPS
341 This option is needed for RDC R-321x system-on-chip, also known
343 If you don't have one of these chips, you should say N here.
346 bool "Support for ScaleMP vSMP"
348 depends on X86_64 && PCI
350 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
351 supposed to run on these EM64T-based machines. Only choose this option
352 if you have one of these machines.
357 bool "SGI 320/540 (Visual Workstation)"
358 depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT
360 The SGI Visual Workstation series is an IA32-based workstation
361 based on SGI systems chips with some legacy PC hardware attached.
363 Say Y here to create a kernel to run on the SGI 320 or 540.
365 A kernel compiled for the Visual Workstation will run on general
366 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
368 config SCHED_NO_NO_OMIT_FRAME_POINTER
370 prompt "Single-depth WCHAN output"
373 Calculate simpler /proc/<PID>/wchan values. If this option
374 is disabled then wchan values will recurse back to the
375 caller function. This provides more accurate wchan values,
376 at the expense of slightly more scheduling overhead.
378 If in doubt, say "Y".
380 menuconfig PARAVIRT_GUEST
381 bool "Paravirtualized guest support"
383 Say Y here to get to see options related to running Linux under
384 various hypervisors. This option alone does not add any kernel code.
386 If you say N, all options in this submenu will be skipped and disabled.
390 source "arch/x86/xen/Kconfig"
393 bool "VMI Guest support"
396 depends on !X86_VOYAGER
398 VMI provides a paravirtualized interface to the VMware ESX server
399 (it could be used by other hypervisors in theory too, but is not
400 at the moment), by linking the kernel to a GPL-ed ROM module
401 provided by the hypervisor.
404 bool "KVM paravirtualized clock"
406 select PARAVIRT_CLOCK
407 depends on !X86_VOYAGER
409 Turning on this option will allow you to run a paravirtualized clock
410 when running over the KVM hypervisor. Instead of relying on a PIT
411 (or probably other) emulation by the underlying device model, the host
412 provides the guest with timing infrastructure such as time of day, and
416 bool "KVM Guest support"
418 depends on !X86_VOYAGER
420 This option enables various optimizations for running under the KVM
423 source "arch/x86/lguest/Kconfig"
426 bool "Enable paravirtualization code"
427 depends on !X86_VOYAGER
429 This changes the kernel so it can modify itself when it is run
430 under a hypervisor, potentially improving performance significantly
431 over full virtualization. However, when run without a hypervisor
432 the kernel is theoretically slower and slightly larger.
434 config PARAVIRT_CLOCK
440 config PARAVIRT_DEBUG
441 bool "paravirt-ops debugging"
442 depends on PARAVIRT && DEBUG_KERNEL
444 Enable to debug paravirt_ops internals. Specifically, BUG if
445 a paravirt_op is missing when it is called.
451 This option adds a kernel parameter 'memtest', which allows memtest
453 memtest=0, mean disabled; -- default
454 memtest=1, mean do 1 test pattern;
456 memtest=4, mean do 4 test patterns.
457 If you are unsure how to answer this question, answer N.
459 config X86_SUMMIT_NUMA
461 depends on X86_32 && NUMA && X86_GENERICARCH
463 config X86_CYCLONE_TIMER
465 depends on X86_GENERICARCH
467 config ES7000_CLUSTERED_APIC
469 depends on SMP && X86_ES7000 && MPENTIUMIII
471 source "arch/x86/Kconfig.cpu"
475 prompt "HPET Timer Support" if X86_32
477 Use the IA-PC HPET (High Precision Event Timer) to manage
478 time in preference to the PIT and RTC, if a HPET is
480 HPET is the next generation timer replacing legacy 8254s.
481 The HPET provides a stable time base on SMP
482 systems, unlike the TSC, but it is more expensive to access,
483 as it is off-chip. You can find the HPET spec at
484 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
486 You can safely choose Y here. However, HPET will only be
487 activated if the platform and the BIOS support this feature.
488 Otherwise the 8254 will be used for timing services.
490 Choose N to continue using the legacy 8254 timer.
492 config HPET_EMULATE_RTC
494 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
496 # Mark as embedded because too many people got it wrong.
497 # The code disables itself when not needed.
500 bool "Enable DMI scanning" if EMBEDDED
502 Enabled scanning of DMI to identify machine quirks. Say Y
503 here unless you have verified that your setup is not
504 affected by entries in the DMI blacklist. Required by PNP
508 bool "GART IOMMU support" if EMBEDDED
512 depends on X86_64 && PCI
514 Support for full DMA access of devices with 32bit memory access only
515 on systems with more than 3GB. This is usually needed for USB,
516 sound, many IDE/SATA chipsets and some other devices.
517 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
518 based hardware IOMMU and a software bounce buffer based IOMMU used
519 on Intel systems and as fallback.
520 The code is only active when needed (enough memory and limited
521 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
525 bool "IBM Calgary IOMMU support"
527 depends on X86_64 && PCI && EXPERIMENTAL
529 Support for hardware IOMMUs in IBM's xSeries x366 and x460
530 systems. Needed to run systems with more than 3GB of memory
531 properly with 32-bit PCI devices that do not support DAC
532 (Double Address Cycle). Calgary also supports bus level
533 isolation, where all DMAs pass through the IOMMU. This
534 prevents them from going anywhere except their intended
535 destination. This catches hard-to-find kernel bugs and
536 mis-behaving drivers and devices that do not use the DMA-API
537 properly to set up their DMA buffers. The IOMMU can be
538 turned off at boot time with the iommu=off parameter.
539 Normally the kernel will make the right choice by itself.
542 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
544 prompt "Should Calgary be enabled by default?"
545 depends on CALGARY_IOMMU
547 Should Calgary be enabled by default? if you choose 'y', Calgary
548 will be used (if it exists). If you choose 'n', Calgary will not be
549 used even if it exists. If you choose 'n' and would like to use
550 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
554 bool "AMD IOMMU support"
556 depends on X86_64 && PCI && ACPI
558 With this option you can enable support for AMD IOMMU hardware in
559 your system. An IOMMU is a hardware component which provides
560 remapping of DMA memory accesses from devices. With an AMD IOMMU you
561 can isolate the the DMA memory of different devices and protect the
562 system from misbehaving device drivers or hardware.
564 You can find out if your system has an AMD IOMMU if you look into
565 your BIOS for an option to enable it or if you have an IVRS ACPI
568 # need this always selected by IOMMU for the VIA workaround
572 Support for software bounce buffers used on x86-64 systems
573 which don't have a hardware IOMMU (e.g. the current generation
574 of Intel's x86-64 CPUs). Using this PCI devices which can only
575 access 32-bits of memory can be used on systems with more than
576 3 GB of memory. If unsure, say Y.
579 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
581 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
582 depends on X86_64 && SMP
585 Configure maximum number of CPUS and NUMA Nodes for this architecture.
596 int "Maximum number of CPUs (2-4096)"
599 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
602 This allows you to specify the maximum number of CPUs which this
603 kernel will support. The maximum supported value is 4096 and the
604 minimum value which makes sense is 2.
606 This is purely to save memory - each supported CPU adds
607 approximately eight kilobytes to the kernel image.
611 bool "SMT (Hyperthreading) scheduler support"
614 SMT scheduler support improves the CPU scheduler's decision making
615 when dealing with Intel Pentium 4 chips with HyperThreading at a
616 cost of slightly increased overhead in some places. If unsure say
621 prompt "Multi-core scheduler support"
624 Multi-core scheduler support improves the CPU scheduler's decision
625 making when dealing with multi-core CPU chips at a cost of slightly
626 increased overhead in some places. If unsure say N here.
628 source "kernel/Kconfig.preempt"
631 bool "Local APIC support on uniprocessors"
632 depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH)
634 A local APIC (Advanced Programmable Interrupt Controller) is an
635 integrated interrupt controller in the CPU. If you have a single-CPU
636 system which has a processor with a local APIC, you can say Y here to
637 enable and use it. If you say Y here even though your machine doesn't
638 have a local APIC, then the kernel will still run with no slowdown at
639 all. The local APIC supports CPU-generated self-interrupts (timer,
640 performance counters), and the NMI watchdog which detects hard
644 bool "IO-APIC support on uniprocessors"
645 depends on X86_UP_APIC
647 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
648 SMP-capable replacement for PC-style interrupt controllers. Most
649 SMP systems and many recent uniprocessor systems have one.
651 If you have a single-CPU system with an IO-APIC, you can say Y here
652 to use it. If you say Y here even though your machine doesn't have
653 an IO-APIC, then the kernel will still run with no slowdown at all.
655 config X86_LOCAL_APIC
657 depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
661 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
663 config X86_VISWS_APIC
665 depends on X86_32 && X86_VISWS
668 bool "Machine Check Exception"
669 depends on !X86_VOYAGER
671 Machine Check Exception support allows the processor to notify the
672 kernel if it detects a problem (e.g. overheating, component failure).
673 The action the kernel takes depends on the severity of the problem,
674 ranging from a warning message on the console, to halting the machine.
675 Your processor must be a Pentium or newer to support this - check the
676 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
677 have a design flaw which leads to false MCE events - hence MCE is
678 disabled on all P5 processors, unless explicitly enabled with "mce"
679 as a boot argument. Similarly, if MCE is built in and creates a
680 problem on some new non-standard machine, you can boot with "nomce"
681 to disable it. MCE support simply ignores non-MCE processors like
682 the 386 and 486, so nearly everyone can say Y here.
686 prompt "Intel MCE features"
687 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
689 Additional support for intel specific MCE features such as
694 prompt "AMD MCE features"
695 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
697 Additional support for AMD specific MCE features such as
698 the DRAM Error Threshold.
700 config X86_MCE_NONFATAL
701 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
702 depends on X86_32 && X86_MCE
704 Enabling this feature starts a timer that triggers every 5 seconds which
705 will look at the machine check registers to see if anything happened.
706 Non-fatal problems automatically get corrected (but still logged).
707 Disable this if you don't want to see these messages.
708 Seeing the messages this option prints out may be indicative of dying
709 or out-of-spec (ie, overclocked) hardware.
710 This option only does something on certain CPUs.
711 (AMD Athlon/Duron and Intel Pentium 4)
713 config X86_MCE_P4THERMAL
714 bool "check for P4 thermal throttling interrupt."
715 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
717 Enabling this feature will cause a message to be printed when the P4
718 enters thermal throttling.
721 bool "Enable VM86 support" if EMBEDDED
725 This option is required by programs like DOSEMU to run 16-bit legacy
726 code on X86 processors. It also may be needed by software like
727 XFree86 to initialize some video cards via BIOS. Disabling this
728 option saves about 6k.
731 tristate "Toshiba Laptop support"
734 This adds a driver to safely access the System Management Mode of
735 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
736 not work on models with a Phoenix BIOS. The System Management Mode
737 is used to set the BIOS and power saving options on Toshiba portables.
739 For information on utilities to make use of this driver see the
740 Toshiba Linux utilities web site at:
741 <http://www.buzzard.org.uk/toshiba/>.
743 Say Y if you intend to run this kernel on a Toshiba portable.
747 tristate "Dell laptop support"
749 This adds a driver to safely access the System Management Mode
750 of the CPU on the Dell Inspiron 8000. The System Management Mode
751 is used to read cpu temperature and cooling fan status and to
752 control the fans on the I8K portables.
754 This driver has been tested only on the Inspiron 8000 but it may
755 also work with other Dell laptops. You can force loading on other
756 models by passing the parameter `force=1' to the module. Use at
759 For information on utilities to make use of this driver see the
760 I8K Linux utilities web site at:
761 <http://people.debian.org/~dz/i8k/>
763 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
766 config X86_REBOOTFIXUPS
768 prompt "Enable X86 board specific fixups for reboot"
769 depends on X86_32 && X86
771 This enables chipset and/or board specific fixups to be done
772 in order to get reboot to work correctly. This is only needed on
773 some combinations of hardware and BIOS. The symptom, for which
774 this config is intended, is when reboot ends with a stalled/hung
777 Currently, the only fixup is for the Geode machines using
778 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
780 Say Y if you want to enable the fixup. Currently, it's safe to
781 enable this option even if you don't need it.
785 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
788 If you say Y here, you will be able to update the microcode on
789 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
790 Pentium III, Pentium 4, Xeon etc. You will obviously need the
791 actual microcode binary data itself which is not shipped with the
794 For latest news and information on obtaining all the required
795 ingredients for this driver, check:
796 <http://www.urbanmyth.org/microcode/>.
798 To compile this driver as a module, choose M here: the
799 module will be called microcode.
801 config MICROCODE_OLD_INTERFACE
806 tristate "/dev/cpu/*/msr - Model-specific register support"
808 This device gives privileged processes access to the x86
809 Model-Specific Registers (MSRs). It is a character device with
810 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
811 MSR accesses are directed to a specific CPU on multi-processor
815 tristate "/dev/cpu/*/cpuid - CPU information support"
817 This device gives processes access to the x86 CPUID instruction to
818 be executed on a specific processor. It is a character device
819 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
823 prompt "High Memory Support"
824 default HIGHMEM4G if !X86_NUMAQ
825 default HIGHMEM64G if X86_NUMAQ
830 depends on !X86_NUMAQ
832 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
833 However, the address space of 32-bit x86 processors is only 4
834 Gigabytes large. That means that, if you have a large amount of
835 physical memory, not all of it can be "permanently mapped" by the
836 kernel. The physical memory that's not permanently mapped is called
839 If you are compiling a kernel which will never run on a machine with
840 more than 1 Gigabyte total physical RAM, answer "off" here (default
841 choice and suitable for most users). This will result in a "3GB/1GB"
842 split: 3GB are mapped so that each process sees a 3GB virtual memory
843 space and the remaining part of the 4GB virtual memory space is used
844 by the kernel to permanently map as much physical memory as
847 If the machine has between 1 and 4 Gigabytes physical RAM, then
850 If more than 4 Gigabytes is used then answer "64GB" here. This
851 selection turns Intel PAE (Physical Address Extension) mode on.
852 PAE implements 3-level paging on IA32 processors. PAE is fully
853 supported by Linux, PAE mode is implemented on all recent Intel
854 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
855 then the kernel will not boot on CPUs that don't support PAE!
857 The actual amount of total physical memory will either be
858 auto detected or can be forced by using a kernel command line option
859 such as "mem=256M". (Try "man bootparam" or see the documentation of
860 your boot loader (lilo or loadlin) about how to pass options to the
861 kernel at boot time.)
863 If unsure, say "off".
867 depends on !X86_NUMAQ
869 Select this if you have a 32-bit processor and between 1 and 4
870 gigabytes of physical RAM.
874 depends on !M386 && !M486
877 Select this if you have a 32-bit processor and more than 4
878 gigabytes of physical RAM.
883 depends on EXPERIMENTAL
884 prompt "Memory split" if EMBEDDED
888 Select the desired split between kernel and user memory.
890 If the address range available to the kernel is less than the
891 physical memory installed, the remaining memory will be available
892 as "high memory". Accessing high memory is a little more costly
893 than low memory, as it needs to be mapped into the kernel first.
894 Note that increasing the kernel address space limits the range
895 available to user programs, making the address space there
896 tighter. Selecting anything other than the default 3G/1G split
897 will also likely make your kernel incompatible with binary-only
900 If you are not absolutely sure what you are doing, leave this
904 bool "3G/1G user/kernel split"
905 config VMSPLIT_3G_OPT
907 bool "3G/1G user/kernel split (for full 1G low memory)"
909 bool "2G/2G user/kernel split"
910 config VMSPLIT_2G_OPT
912 bool "2G/2G user/kernel split (for full 2G low memory)"
914 bool "1G/3G user/kernel split"
919 default 0xB0000000 if VMSPLIT_3G_OPT
920 default 0x80000000 if VMSPLIT_2G
921 default 0x78000000 if VMSPLIT_2G_OPT
922 default 0x40000000 if VMSPLIT_1G
928 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
932 prompt "PAE (Physical Address Extension) Support"
933 depends on X86_32 && !HIGHMEM4G
934 select RESOURCES_64BIT
936 PAE is required for NX support, and furthermore enables
937 larger swapspace support for non-overcommit purposes. It
938 has the cost of more pagetable lookup overhead, and also
939 consumes more pagetable space per process.
941 # Common NUMA Features
943 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
945 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
947 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
949 Enable NUMA (Non Uniform Memory Access) support.
950 The kernel will try to allocate memory used by a CPU on the
951 local memory controller of the CPU and add some more
952 NUMA awareness to the kernel.
954 For i386 this is currently highly experimental and should be only
955 used for kernel development. It might also cause boot failures.
956 For x86_64 this is recommended on all multiprocessor Opteron systems.
957 If the system is EM64T, you should say N unless your system is
960 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
961 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
965 prompt "Old style AMD Opteron NUMA detection"
966 depends on X86_64 && NUMA && PCI
968 Enable K8 NUMA node topology detection. You should say Y here if
969 you have a multi processor AMD K8 system. This uses an old
970 method to read the NUMA configuration directly from the builtin
971 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
972 instead, which also takes priority if both are compiled in.
974 config X86_64_ACPI_NUMA
976 prompt "ACPI NUMA detection"
977 depends on X86_64 && NUMA && ACPI && PCI
980 Enable ACPI SRAT based node topology detection.
982 # Some NUMA nodes have memory ranges that span
983 # other nodes. Even though a pfn is valid and
984 # between a node's start and end pfns, it may not
985 # reside on that node. See memmap_init_zone()
987 config NODES_SPAN_OTHER_NODES
989 depends on X86_64_ACPI_NUMA
992 bool "NUMA emulation"
993 depends on X86_64 && NUMA
995 Enable NUMA emulation. A flat machine will be split
996 into virtual nodes when booted with "numa=fake=N", where N is the
997 number of nodes. This is only useful for debugging.
1008 int "Maximum NUMA Nodes (as a power of 2)"
1010 default "6" if X86_64
1011 default "4" if X86_NUMAQ
1013 depends on NEED_MULTIPLE_NODES
1015 Specify the maximum number of NUMA Nodes available on the target
1016 system. Increases memory reserved to accomodate various tables.
1019 config HAVE_ARCH_BOOTMEM_NODE
1021 depends on X86_32 && NUMA
1023 config ARCH_HAVE_MEMORY_PRESENT
1025 depends on X86_32 && DISCONTIGMEM
1027 config NEED_NODE_MEMMAP_SIZE
1029 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1031 config HAVE_ARCH_ALLOC_REMAP
1033 depends on X86_32 && NUMA
1035 config ARCH_FLATMEM_ENABLE
1037 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
1039 config ARCH_DISCONTIGMEM_ENABLE
1041 depends on NUMA && X86_32
1043 config ARCH_DISCONTIGMEM_DEFAULT
1045 depends on NUMA && X86_32
1047 config ARCH_SPARSEMEM_DEFAULT
1051 config ARCH_SPARSEMEM_ENABLE
1053 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1054 select SPARSEMEM_STATIC if X86_32
1055 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1057 config ARCH_SELECT_MEMORY_MODEL
1059 depends on ARCH_SPARSEMEM_ENABLE
1061 config ARCH_MEMORY_PROBE
1063 depends on MEMORY_HOTPLUG
1068 bool "Allocate 3rd-level pagetables from highmem"
1069 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1071 The VM uses one page table entry for each page of physical memory.
1072 For systems with a lot of RAM, this can be wasteful of precious
1073 low memory. Setting this option will put user-space page table
1074 entries in high memory.
1076 config MATH_EMULATION
1078 prompt "Math emulation" if X86_32
1080 Linux can emulate a math coprocessor (used for floating point
1081 operations) if you don't have one. 486DX and Pentium processors have
1082 a math coprocessor built in, 486SX and 386 do not, unless you added
1083 a 487DX or 387, respectively. (The messages during boot time can
1084 give you some hints here ["man dmesg"].) Everyone needs either a
1085 coprocessor or this emulation.
1087 If you don't have a math coprocessor, you need to say Y here; if you
1088 say Y here even though you have a coprocessor, the coprocessor will
1089 be used nevertheless. (This behavior can be changed with the kernel
1090 command line option "no387", which comes handy if your coprocessor
1091 is broken. Try "man bootparam" or see the documentation of your boot
1092 loader (lilo or loadlin) about how to pass options to the kernel at
1093 boot time.) This means that it is a good idea to say Y here if you
1094 intend to use this kernel on different machines.
1096 More information about the internals of the Linux math coprocessor
1097 emulation can be found in <file:arch/x86/math-emu/README>.
1099 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1100 kernel, it won't hurt.
1103 bool "MTRR (Memory Type Range Register) support"
1105 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1106 the Memory Type Range Registers (MTRRs) may be used to control
1107 processor access to memory ranges. This is most useful if you have
1108 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1109 allows bus write transfers to be combined into a larger transfer
1110 before bursting over the PCI/AGP bus. This can increase performance
1111 of image write operations 2.5 times or more. Saying Y here creates a
1112 /proc/mtrr file which may be used to manipulate your processor's
1113 MTRRs. Typically the X server should use this.
1115 This code has a reasonably generic interface so that similar
1116 control registers on other processors can be easily supported
1119 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1120 Registers (ARRs) which provide a similar functionality to MTRRs. For
1121 these, the ARRs are used to emulate the MTRRs.
1122 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1123 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1124 write-combining. All of these processors are supported by this code
1125 and it makes sense to say Y here if you have one of them.
1127 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1128 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1129 can lead to all sorts of problems, so it's good to say Y here.
1131 You can safely say Y even if your machine doesn't have MTRRs, you'll
1132 just add about 9 KB to your kernel.
1134 See <file:Documentation/mtrr.txt> for more information.
1136 config MTRR_SANITIZER
1138 prompt "MTRR cleanup support"
1141 Convert MTRR layout from continuous to discrete, so X drivers can
1142 add writeback entries.
1144 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1145 The largest mtrr entry size for a continous block can be set with
1150 config MTRR_SANITIZER_ENABLE_DEFAULT
1151 int "MTRR cleanup enable value (0-1)"
1154 depends on MTRR_SANITIZER
1156 Enable mtrr cleanup default value
1158 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1159 int "MTRR cleanup spare reg num (0-7)"
1162 depends on MTRR_SANITIZER
1164 mtrr cleanup spare entries default, it can be changed via
1165 mtrr_spare_reg_nr=N on the kernel command line.
1169 prompt "x86 PAT support"
1172 Use PAT attributes to setup page level cache control.
1174 PATs are the modern equivalents of MTRRs and are much more
1175 flexible than MTRRs.
1177 Say N here if you see bootup problems (boot crash, boot hang,
1178 spontaneous reboots) or a non-working video driver.
1184 prompt "EFI runtime service support"
1187 This enables the kernel to use EFI runtime services that are
1188 available (such as the EFI variable services).
1190 This option is only useful on systems that have EFI firmware.
1191 In addition, you should use the latest ELILO loader available
1192 at <http://elilo.sourceforge.net> in order to take advantage
1193 of EFI runtime services. However, even with this option, the
1194 resultant kernel should continue to boot on existing non-EFI
1199 prompt "Enable kernel irq balancing"
1200 depends on X86_32 && SMP && X86_IO_APIC
1202 The default yes will allow the kernel to do irq load balancing.
1203 Saying no will keep the kernel from doing irq load balancing.
1207 prompt "Enable seccomp to safely compute untrusted bytecode"
1210 This kernel feature is useful for number crunching applications
1211 that may need to compute untrusted bytecode during their
1212 execution. By using pipes or other transports made available to
1213 the process as file descriptors supporting the read/write
1214 syscalls, it's possible to isolate those applications in
1215 their own address space using seccomp. Once seccomp is
1216 enabled via /proc/<pid>/seccomp, it cannot be disabled
1217 and the task is only allowed to execute a few safe syscalls
1218 defined by each seccomp mode.
1220 If unsure, say Y. Only embedded should say N here.
1222 config CC_STACKPROTECTOR
1223 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1224 depends on X86_64 && EXPERIMENTAL && BROKEN
1226 This option turns on the -fstack-protector GCC feature. This
1227 feature puts, at the beginning of critical functions, a canary
1228 value on the stack just before the return address, and validates
1229 the value just before actually returning. Stack based buffer
1230 overflows (that need to overwrite this return address) now also
1231 overwrite the canary, which gets detected and the attack is then
1232 neutralized via a kernel panic.
1234 This feature requires gcc version 4.2 or above, or a distribution
1235 gcc with the feature backported. Older versions are automatically
1236 detected and for those versions, this configuration option is ignored.
1238 config CC_STACKPROTECTOR_ALL
1239 bool "Use stack-protector for all functions"
1240 depends on CC_STACKPROTECTOR
1242 Normally, GCC only inserts the canary value protection for
1243 functions that use large-ish on-stack buffers. By enabling
1244 this option, GCC will be asked to do this for ALL functions.
1246 source kernel/Kconfig.hz
1249 bool "kexec system call"
1250 depends on X86_BIOS_REBOOT
1252 kexec is a system call that implements the ability to shutdown your
1253 current kernel, and to start another kernel. It is like a reboot
1254 but it is independent of the system firmware. And like a reboot
1255 you can start any kernel with it, not just Linux.
1257 The name comes from the similarity to the exec system call.
1259 It is an ongoing process to be certain the hardware in a machine
1260 is properly shutdown, so do not be surprised if this code does not
1261 initially work for you. It may help to enable device hotplugging
1262 support. As of this writing the exact hardware interface is
1263 strongly in flux, so no good recommendation can be made.
1266 bool "kernel crash dumps (EXPERIMENTAL)"
1267 depends on X86_64 || (X86_32 && HIGHMEM)
1269 Generate crash dump after being started by kexec.
1270 This should be normally only set in special crash dump kernels
1271 which are loaded in the main kernel with kexec-tools into
1272 a specially reserved region and then later executed after
1273 a crash by kdump/kexec. The crash dump kernel must be compiled
1274 to a memory address not used by the main kernel or BIOS using
1275 PHYSICAL_START, or it must be built as a relocatable image
1276 (CONFIG_RELOCATABLE=y).
1277 For more details see Documentation/kdump/kdump.txt
1279 config PHYSICAL_START
1280 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1281 default "0x1000000" if X86_NUMAQ
1282 default "0x200000" if X86_64
1285 This gives the physical address where the kernel is loaded.
1287 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1288 bzImage will decompress itself to above physical address and
1289 run from there. Otherwise, bzImage will run from the address where
1290 it has been loaded by the boot loader and will ignore above physical
1293 In normal kdump cases one does not have to set/change this option
1294 as now bzImage can be compiled as a completely relocatable image
1295 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1296 address. This option is mainly useful for the folks who don't want
1297 to use a bzImage for capturing the crash dump and want to use a
1298 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1299 to be specifically compiled to run from a specific memory area
1300 (normally a reserved region) and this option comes handy.
1302 So if you are using bzImage for capturing the crash dump, leave
1303 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1304 Otherwise if you plan to use vmlinux for capturing the crash dump
1305 change this value to start of the reserved region (Typically 16MB
1306 0x1000000). In other words, it can be set based on the "X" value as
1307 specified in the "crashkernel=YM@XM" command line boot parameter
1308 passed to the panic-ed kernel. Typically this parameter is set as
1309 crashkernel=64M@16M. Please take a look at
1310 Documentation/kdump/kdump.txt for more details about crash dumps.
1312 Usage of bzImage for capturing the crash dump is recommended as
1313 one does not have to build two kernels. Same kernel can be used
1314 as production kernel and capture kernel. Above option should have
1315 gone away after relocatable bzImage support is introduced. But it
1316 is present because there are users out there who continue to use
1317 vmlinux for dump capture. This option should go away down the
1320 Don't change this unless you know what you are doing.
1323 bool "Build a relocatable kernel (EXPERIMENTAL)"
1324 depends on EXPERIMENTAL
1326 This builds a kernel image that retains relocation information
1327 so it can be loaded someplace besides the default 1MB.
1328 The relocations tend to make the kernel binary about 10% larger,
1329 but are discarded at runtime.
1331 One use is for the kexec on panic case where the recovery kernel
1332 must live at a different physical address than the primary
1335 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1336 it has been loaded at and the compile time physical address
1337 (CONFIG_PHYSICAL_START) is ignored.
1339 config PHYSICAL_ALIGN
1341 prompt "Alignment value to which kernel should be aligned" if X86_32
1342 default "0x100000" if X86_32
1343 default "0x200000" if X86_64
1344 range 0x2000 0x400000
1346 This value puts the alignment restrictions on physical address
1347 where kernel is loaded and run from. Kernel is compiled for an
1348 address which meets above alignment restriction.
1350 If bootloader loads the kernel at a non-aligned address and
1351 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1352 address aligned to above value and run from there.
1354 If bootloader loads the kernel at a non-aligned address and
1355 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1356 load address and decompress itself to the address it has been
1357 compiled for and run from there. The address for which kernel is
1358 compiled already meets above alignment restrictions. Hence the
1359 end result is that kernel runs from a physical address meeting
1360 above alignment restrictions.
1362 Don't change this unless you know what you are doing.
1365 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1366 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1368 Say Y here to experiment with turning CPUs off and on, and to
1369 enable suspend on SMP systems. CPUs can be controlled through
1370 /sys/devices/system/cpu.
1371 Say N if you want to disable CPU hotplug and don't need to
1376 prompt "Compat VDSO support"
1377 depends on X86_32 || IA32_EMULATION
1379 Map the 32-bit VDSO to the predictable old-style address too.
1381 Say N here if you are running a sufficiently recent glibc
1382 version (2.3.3 or later), to remove the high-mapped
1383 VDSO mapping and to exclusively use the randomized VDSO.
1389 config ARCH_ENABLE_MEMORY_HOTPLUG
1391 depends on X86_64 || (X86_32 && HIGHMEM)
1393 config HAVE_ARCH_EARLY_PFN_TO_NID
1397 menu "Power management options"
1398 depends on !X86_VOYAGER
1400 config ARCH_HIBERNATION_HEADER
1402 depends on X86_64 && HIBERNATION
1404 source "kernel/power/Kconfig"
1406 source "drivers/acpi/Kconfig"
1411 depends on APM || APM_MODULE
1414 tristate "APM (Advanced Power Management) BIOS support"
1415 depends on X86_32 && PM_SLEEP
1417 APM is a BIOS specification for saving power using several different
1418 techniques. This is mostly useful for battery powered laptops with
1419 APM compliant BIOSes. If you say Y here, the system time will be
1420 reset after a RESUME operation, the /proc/apm device will provide
1421 battery status information, and user-space programs will receive
1422 notification of APM "events" (e.g. battery status change).
1424 If you select "Y" here, you can disable actual use of the APM
1425 BIOS by passing the "apm=off" option to the kernel at boot time.
1427 Note that the APM support is almost completely disabled for
1428 machines with more than one CPU.
1430 In order to use APM, you will need supporting software. For location
1431 and more information, read <file:Documentation/power/pm.txt> and the
1432 Battery Powered Linux mini-HOWTO, available from
1433 <http://www.tldp.org/docs.html#howto>.
1435 This driver does not spin down disk drives (see the hdparm(8)
1436 manpage ("man 8 hdparm") for that), and it doesn't turn off
1437 VESA-compliant "green" monitors.
1439 This driver does not support the TI 4000M TravelMate and the ACER
1440 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1441 desktop machines also don't have compliant BIOSes, and this driver
1442 may cause those machines to panic during the boot phase.
1444 Generally, if you don't have a battery in your machine, there isn't
1445 much point in using this driver and you should say N. If you get
1446 random kernel OOPSes or reboots that don't seem to be related to
1447 anything, try disabling/enabling this option (or disabling/enabling
1450 Some other things you should try when experiencing seemingly random,
1453 1) make sure that you have enough swap space and that it is
1455 2) pass the "no-hlt" option to the kernel
1456 3) switch on floating point emulation in the kernel and pass
1457 the "no387" option to the kernel
1458 4) pass the "floppy=nodma" option to the kernel
1459 5) pass the "mem=4M" option to the kernel (thereby disabling
1460 all but the first 4 MB of RAM)
1461 6) make sure that the CPU is not over clocked.
1462 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1463 8) disable the cache from your BIOS settings
1464 9) install a fan for the video card or exchange video RAM
1465 10) install a better fan for the CPU
1466 11) exchange RAM chips
1467 12) exchange the motherboard.
1469 To compile this driver as a module, choose M here: the
1470 module will be called apm.
1474 config APM_IGNORE_USER_SUSPEND
1475 bool "Ignore USER SUSPEND"
1477 This option will ignore USER SUSPEND requests. On machines with a
1478 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1479 series notebooks, it is necessary to say Y because of a BIOS bug.
1481 config APM_DO_ENABLE
1482 bool "Enable PM at boot time"
1484 Enable APM features at boot time. From page 36 of the APM BIOS
1485 specification: "When disabled, the APM BIOS does not automatically
1486 power manage devices, enter the Standby State, enter the Suspend
1487 State, or take power saving steps in response to CPU Idle calls."
1488 This driver will make CPU Idle calls when Linux is idle (unless this
1489 feature is turned off -- see "Do CPU IDLE calls", below). This
1490 should always save battery power, but more complicated APM features
1491 will be dependent on your BIOS implementation. You may need to turn
1492 this option off if your computer hangs at boot time when using APM
1493 support, or if it beeps continuously instead of suspending. Turn
1494 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1495 T400CDT. This is off by default since most machines do fine without
1499 bool "Make CPU Idle calls when idle"
1501 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1502 On some machines, this can activate improved power savings, such as
1503 a slowed CPU clock rate, when the machine is idle. These idle calls
1504 are made after the idle loop has run for some length of time (e.g.,
1505 333 mS). On some machines, this will cause a hang at boot time or
1506 whenever the CPU becomes idle. (On machines with more than one CPU,
1507 this option does nothing.)
1509 config APM_DISPLAY_BLANK
1510 bool "Enable console blanking using APM"
1512 Enable console blanking using the APM. Some laptops can use this to
1513 turn off the LCD backlight when the screen blanker of the Linux
1514 virtual console blanks the screen. Note that this is only used by
1515 the virtual console screen blanker, and won't turn off the backlight
1516 when using the X Window system. This also doesn't have anything to
1517 do with your VESA-compliant power-saving monitor. Further, this
1518 option doesn't work for all laptops -- it might not turn off your
1519 backlight at all, or it might print a lot of errors to the console,
1520 especially if you are using gpm.
1522 config APM_ALLOW_INTS
1523 bool "Allow interrupts during APM BIOS calls"
1525 Normally we disable external interrupts while we are making calls to
1526 the APM BIOS as a measure to lessen the effects of a badly behaving
1527 BIOS implementation. The BIOS should reenable interrupts if it
1528 needs to. Unfortunately, some BIOSes do not -- especially those in
1529 many of the newer IBM Thinkpads. If you experience hangs when you
1530 suspend, try setting this to Y. Otherwise, say N.
1532 config APM_REAL_MODE_POWER_OFF
1533 bool "Use real mode APM BIOS call to power off"
1535 Use real mode APM BIOS calls to switch off the computer. This is
1536 a work-around for a number of buggy BIOSes. Switch this option on if
1537 your computer crashes instead of powering off properly.
1541 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1543 source "drivers/cpuidle/Kconfig"
1548 menu "Bus options (PCI etc.)"
1553 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1555 Find out whether you have a PCI motherboard. PCI is the name of a
1556 bus system, i.e. the way the CPU talks to the other stuff inside
1557 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1558 VESA. If you have PCI, say Y, otherwise N.
1561 prompt "PCI access mode"
1562 depends on X86_32 && PCI
1565 On PCI systems, the BIOS can be used to detect the PCI devices and
1566 determine their configuration. However, some old PCI motherboards
1567 have BIOS bugs and may crash if this is done. Also, some embedded
1568 PCI-based systems don't have any BIOS at all. Linux can also try to
1569 detect the PCI hardware directly without using the BIOS.
1571 With this option, you can specify how Linux should detect the
1572 PCI devices. If you choose "BIOS", the BIOS will be used,
1573 if you choose "Direct", the BIOS won't be used, and if you
1574 choose "MMConfig", then PCI Express MMCONFIG will be used.
1575 If you choose "Any", the kernel will try MMCONFIG, then the
1576 direct access method and falls back to the BIOS if that doesn't
1577 work. If unsure, go with the default, which is "Any".
1582 config PCI_GOMMCONFIG
1599 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1601 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1604 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1608 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1612 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1619 bool "Support mmconfig PCI config space access"
1620 depends on X86_64 && PCI && ACPI
1623 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1624 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1626 DMA remapping (DMAR) devices support enables independent address
1627 translations for Direct Memory Access (DMA) from devices.
1628 These DMA remapping devices are reported via ACPI tables
1629 and include PCI device scope covered by these DMA
1634 prompt "Support for Graphics workaround"
1637 Current Graphics drivers tend to use physical address
1638 for DMA and avoid using DMA APIs. Setting this config
1639 option permits the IOMMU driver to set a unity map for
1640 all the OS-visible memory. Hence the driver can continue
1641 to use physical addresses for DMA.
1643 config DMAR_FLOPPY_WA
1647 Floppy disk drivers are know to bypass DMA API calls
1648 thereby failing to work when IOMMU is enabled. This
1649 workaround will setup a 1:1 mapping for the first
1650 16M to make floppy (an ISA device) work.
1652 source "drivers/pci/pcie/Kconfig"
1654 source "drivers/pci/Kconfig"
1656 # x86_64 have no ISA slots, but do have ISA-style DMA.
1664 depends on !X86_VOYAGER
1666 Find out whether you have ISA slots on your motherboard. ISA is the
1667 name of a bus system, i.e. the way the CPU talks to the other stuff
1668 inside your box. Other bus systems are PCI, EISA, MicroChannel
1669 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1670 newer boards don't support it. If you have ISA, say Y, otherwise N.
1676 The Extended Industry Standard Architecture (EISA) bus was
1677 developed as an open alternative to the IBM MicroChannel bus.
1679 The EISA bus provided some of the features of the IBM MicroChannel
1680 bus while maintaining backward compatibility with cards made for
1681 the older ISA bus. The EISA bus saw limited use between 1988 and
1682 1995 when it was made obsolete by the PCI bus.
1684 Say Y here if you are building a kernel for an EISA-based machine.
1688 source "drivers/eisa/Kconfig"
1691 bool "MCA support" if !X86_VOYAGER
1692 default y if X86_VOYAGER
1694 MicroChannel Architecture is found in some IBM PS/2 machines and
1695 laptops. It is a bus system similar to PCI or ISA. See
1696 <file:Documentation/mca.txt> (and especially the web page given
1697 there) before attempting to build an MCA bus kernel.
1699 source "drivers/mca/Kconfig"
1702 tristate "NatSemi SCx200 support"
1703 depends on !X86_VOYAGER
1705 This provides basic support for National Semiconductor's
1706 (now AMD's) Geode processors. The driver probes for the
1707 PCI-IDs of several on-chip devices, so its a good dependency
1708 for other scx200_* drivers.
1710 If compiled as a module, the driver is named scx200.
1712 config SCx200HR_TIMER
1713 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1714 depends on SCx200 && GENERIC_TIME
1717 This driver provides a clocksource built upon the on-chip
1718 27MHz high-resolution timer. Its also a workaround for
1719 NSC Geode SC-1100's buggy TSC, which loses time when the
1720 processor goes idle (as is done by the scheduler). The
1721 other workaround is idle=poll boot option.
1723 config GEODE_MFGPT_TIMER
1725 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1726 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1728 This driver provides a clock event source based on the MFGPT
1729 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1730 MFGPTs have a better resolution and max interval than the
1731 generic PIT, and are suitable for use as high-res timers.
1734 bool "One Laptop Per Child support"
1737 Add support for detecting the unique features of the OLPC
1744 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1746 source "drivers/pcmcia/Kconfig"
1748 source "drivers/pci/hotplug/Kconfig"
1753 menu "Executable file formats / Emulations"
1755 source "fs/Kconfig.binfmt"
1757 config IA32_EMULATION
1758 bool "IA32 Emulation"
1760 select COMPAT_BINFMT_ELF
1762 Include code to run 32-bit programs under a 64-bit kernel. You should
1763 likely turn this on, unless you're 100% sure that you don't have any
1764 32-bit programs left.
1767 tristate "IA32 a.out support"
1768 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1770 Support old a.out binaries in the 32bit emulation.
1774 depends on IA32_EMULATION
1776 config COMPAT_FOR_U64_ALIGNMENT
1780 config SYSVIPC_COMPAT
1782 depends on X86_64 && COMPAT && SYSVIPC
1787 source "net/Kconfig"
1789 source "drivers/Kconfig"
1791 source "drivers/firmware/Kconfig"
1795 source "arch/x86/Kconfig.debug"
1797 source "security/Kconfig"
1799 source "crypto/Kconfig"
1801 source "arch/x86/kvm/Kconfig"
1803 source "lib/Kconfig"
projects / mirror_ubuntu-hirsute-kernel.git / blob