# x86 configuration

mainmenu "Linux Kernel Configuration for x86"

# Select 32 or 64 bit

config 64BIT

bool "64-bit kernel" if ARCH = "x86"

default ARCH = "x86_64"

---help---

Say yes to build a 64-bit kernel - formerly known as x86_64

Say no to build a 32-bit kernel - formerly known as i386

config X86_32

def_bool !64BIT

config X86_64

def_bool 64BIT

### Arch settings

config X86

def_bool y

select HAVE_AOUT if X86_32

select HAVE_READQ

select HAVE_WRITEQ

select HAVE_UNSTABLE_SCHED_CLOCK

select HAVE_IDE

select HAVE_OPROFILE

select HAVE_PERF_EVENTS if (!M386 && !M486)

select HAVE_IOREMAP_PROT

select HAVE_KPROBES

select ARCH_WANT_OPTIONAL_GPIOLIB

select ARCH_WANT_FRAME_POINTERS

select HAVE_DMA_ATTRS

select HAVE_KRETPROBES

select HAVE_FTRACE_MCOUNT_RECORD

select HAVE_DYNAMIC_FTRACE

select HAVE_FUNCTION_TRACER

select HAVE_FUNCTION_GRAPH_TRACER

select HAVE_FUNCTION_GRAPH_FP_TEST

select HAVE_FUNCTION_TRACE_MCOUNT_TEST

select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE

select HAVE_SYSCALL_TRACEPOINTS

select HAVE_KVM

select HAVE_ARCH_KGDB

select HAVE_ARCH_TRACEHOOK

select HAVE_GENERIC_DMA_COHERENT if X86_32

select HAVE_EFFICIENT_UNALIGNED_ACCESS

select USER_STACKTRACE_SUPPORT

select HAVE_DMA_API_DEBUG

select HAVE_KERNEL_GZIP

select HAVE_KERNEL_BZIP2

select HAVE_KERNEL_LZMA

select HAVE_HW_BREAKPOINT

select PERF_EVENTS

select ANON_INODES

select HAVE_ARCH_KMEMCHECK

select HAVE_USER_RETURN_NOTIFIER

config OUTPUT_FORMAT

string

default "elf32-i386" if X86_32

default "elf64-x86-64" if X86_64

config ARCH_DEFCONFIG

string

default "arch/x86/configs/i386_defconfig" if X86_32

default "arch/x86/configs/x86_64_defconfig" if X86_64

config GENERIC_TIME

def_bool y

config GENERIC_CMOS_UPDATE

def_bool y

config CLOCKSOURCE_WATCHDOG

def_bool y

config GENERIC_CLOCKEVENTS

def_bool y

config GENERIC_CLOCKEVENTS_BROADCAST

def_bool y

depends on X86_64 || (X86_32 && X86_LOCAL_APIC)

config LOCKDEP_SUPPORT

def_bool y

config STACKTRACE_SUPPORT

def_bool y

config HAVE_LATENCYTOP_SUPPORT

def_bool y

config MMU

def_bool y

config ZONE_DMA

def_bool y

config SBUS

bool

config GENERIC_ISA_DMA

def_bool y

config GENERIC_IOMAP

def_bool y

config GENERIC_BUG

def_bool y

depends on BUG

select GENERIC_BUG_RELATIVE_POINTERS if X86_64

config GENERIC_BUG_RELATIVE_POINTERS

bool

config GENERIC_HWEIGHT

def_bool y

config GENERIC_GPIO

bool

config ARCH_MAY_HAVE_PC_FDC

def_bool y

config RWSEM_GENERIC_SPINLOCK

def_bool !X86_XADD

config RWSEM_XCHGADD_ALGORITHM

def_bool X86_XADD

config ARCH_HAS_CPU_IDLE_WAIT

def_bool y

config GENERIC_CALIBRATE_DELAY

def_bool y

config GENERIC_TIME_VSYSCALL

bool

default X86_64

config ARCH_HAS_CPU_RELAX

def_bool y

config ARCH_HAS_DEFAULT_IDLE

def_bool y

config ARCH_HAS_CACHE_LINE_SIZE

def_bool y

config HAVE_SETUP_PER_CPU_AREA

def_bool y

config NEED_PER_CPU_EMBED_FIRST_CHUNK

def_bool y

config NEED_PER_CPU_PAGE_FIRST_CHUNK

def_bool y

config HAVE_CPUMASK_OF_CPU_MAP

def_bool X86_64_SMP

config ARCH_HIBERNATION_POSSIBLE

def_bool y

config ARCH_SUSPEND_POSSIBLE

def_bool y

config ZONE_DMA32

bool

default X86_64

config ARCH_POPULATES_NODE_MAP

def_bool y

config AUDIT_ARCH

bool

default X86_64

config ARCH_SUPPORTS_OPTIMIZED_INLINING

def_bool y

config ARCH_SUPPORTS_DEBUG_PAGEALLOC

def_bool y

config HAVE_INTEL_TXT

def_bool y

depends on EXPERIMENTAL && DMAR && ACPI

# Use the generic interrupt handling code in kernel/irq/:

config GENERIC_HARDIRQS

bool

default y

config GENERIC_HARDIRQS_NO__DO_IRQ

def_bool y

config GENERIC_IRQ_PROBE

bool

default y

config GENERIC_PENDING_IRQ

bool

depends on GENERIC_HARDIRQS && SMP

default y

config USE_GENERIC_SMP_HELPERS

def_bool y

depends on SMP

config X86_32_SMP

def_bool y

depends on X86_32 && SMP

config X86_64_SMP

def_bool y

depends on X86_64 && SMP

config X86_HT

bool

depends on SMP

default y

config X86_TRAMPOLINE

bool

depends on SMP || (64BIT && ACPI_SLEEP)

default y

config X86_32_LAZY_GS

def_bool y

depends on X86_32 && !CC_STACKPROTECTOR

config KTIME_SCALAR

def_bool X86_32

source "init/Kconfig"

source "kernel/Kconfig.freezer"

menu "Processor type and features"

source "kernel/time/Kconfig"

config SMP

bool "Symmetric multi-processing support"

---help---

This enables support for systems with more than one CPU. If you have

a system with only one CPU, like most personal computers, say N. If

you have a system with more than one CPU, say Y.

If you say N here, the kernel will run on single and multiprocessor

machines, but will use only one CPU of a multiprocessor machine. If

you say Y here, the kernel will run on many, but not all,

singleprocessor machines. On a singleprocessor machine, the kernel

will run faster if you say N here.

Note that if you say Y here and choose architecture "586" or

"Pentium" under "Processor family", the kernel will not work on 486

architectures. Similarly, multiprocessor kernels for the "PPro"

architecture may not work on all Pentium based boards.

People using multiprocessor machines who say Y here should also say

Y to "Enhanced Real Time Clock Support", below. The "Advanced Power

Management" code will be disabled if you say Y here.

See also <file:Documentation/i386/IO-APIC.txt>,

<file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at

<http://www.tldp.org/docs.html#howto>.

If you don't know what to do here, say N.

config X86_X2APIC

bool "Support x2apic"

depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP

---help---

This enables x2apic support on CPUs that have this feature.

This allows 32-bit apic IDs (so it can support very large systems),

and accesses the local apic via MSRs not via mmio.

If you don't know what to do here, say N.

config SPARSE_IRQ

bool "Support sparse irq numbering"

depends on PCI_MSI || HT_IRQ

---help---

This enables support for sparse irqs. This is useful for distro

kernels that want to define a high CONFIG_NR_CPUS value but still

want to have low kernel memory footprint on smaller machines.

( Sparse IRQs can also be beneficial on NUMA boxes, as they spread

out the irq_desc[] array in a more NUMA-friendly way. )

If you don't know what to do here, say N.

config NUMA_IRQ_DESC

def_bool y

depends on SPARSE_IRQ && NUMA

config X86_MPPARSE

bool "Enable MPS table" if ACPI

default y

depends on X86_LOCAL_APIC

---help---

For old smp systems that do not have proper acpi support. Newer systems

(esp with 64bit cpus) with acpi support, MADT and DSDT will override it

config X86_BIGSMP

bool "Support for big SMP systems with more than 8 CPUs"

depends on X86_32 && SMP

---help---

This option is needed for the systems that have more than 8 CPUs

if X86_32

config X86_EXTENDED_PLATFORM

bool "Support for extended (non-PC) x86 platforms"

default y

---help---

If you disable this option then the kernel will only support

standard PC platforms. (which covers the vast majority of

systems out there.)

If you enable this option then you'll be able to select support

for the following (non-PC) 32 bit x86 platforms:

AMD Elan

NUMAQ (IBM/Sequent)

RDC R-321x SoC

SGI 320/540 (Visual Workstation)

Summit/EXA (IBM x440)

Unisys ES7000 IA32 series

Moorestown MID devices

If you have one of these systems, or if you want to build a

generic distribution kernel, say Y here - otherwise say N.

endif

if X86_64

config X86_EXTENDED_PLATFORM

bool "Support for extended (non-PC) x86 platforms"

default y

---help---

If you disable this option then the kernel will only support

standard PC platforms. (which covers the vast majority of

systems out there.)

If you enable this option then you'll be able to select support

for the following (non-PC) 64 bit x86 platforms:

ScaleMP vSMP

SGI Ultraviolet

If you have one of these systems, or if you want to build a

generic distribution kernel, say Y here - otherwise say N.

endif

# This is an alphabetically sorted list of 64 bit extended platforms

# Please maintain the alphabetic order if and when there are additions

config X86_VSMP

bool "ScaleMP vSMP"

select PARAVIRT

depends on X86_64 && PCI

depends on X86_EXTENDED_PLATFORM

---help---

Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is

supposed to run on these EM64T-based machines. Only choose this option

if you have one of these machines.

config X86_UV

bool "SGI Ultraviolet"

depends on X86_64

depends on X86_EXTENDED_PLATFORM

depends on NUMA

depends on X86_X2APIC

---help---

This option is needed in order to support SGI Ultraviolet systems.

If you don't have one of these, you should say N here.

# Following is an alphabetically sorted list of 32 bit extended platforms

# Please maintain the alphabetic order if and when there are additions

config X86_ELAN

bool "AMD Elan"

depends on X86_32

depends on X86_EXTENDED_PLATFORM

---help---

Select this for an AMD Elan processor.

Do not use this option for K6/Athlon/Opteron processors!

If unsure, choose "PC-compatible" instead.

config X86_MRST

bool "Moorestown MID platform"

depends on X86_32

depends on X86_EXTENDED_PLATFORM

---help---

Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin

Internet Device(MID) platform. Moorestown consists of two chips:

Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.

Unlike standard x86 PCs, Moorestown does not have many legacy devices

nor standard legacy replacement devices/features. e.g. Moorestown does

not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.

config X86_RDC321X

bool "RDC R-321x SoC"

depends on X86_32

depends on X86_EXTENDED_PLATFORM

select M486

select X86_REBOOTFIXUPS

---help---

This option is needed for RDC R-321x system-on-chip, also known

as R-8610-(G).

If you don't have one of these chips, you should say N here.

config X86_32_NON_STANDARD

bool "Support non-standard 32-bit SMP architectures"

depends on X86_32 && SMP

depends on X86_EXTENDED_PLATFORM

---help---

This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default

subarchitectures. It is intended for a generic binary kernel.

if you select them all, kernel will probe it one by one. and will

fallback to default.

# Alphabetically sorted list of Non standard 32 bit platforms

config X86_NUMAQ

bool "NUMAQ (IBM/Sequent)"

depends on X86_32_NON_STANDARD

select NUMA

select X86_MPPARSE

---help---

This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)

NUMA multiquad box. This changes the way that processors are

bootstrapped, and uses Clustered Logical APIC addressing mode instead

of Flat Logical. You will need a new lynxer.elf file to flash your

firmware with - send email to <Martin.Bligh@us.ibm.com>.

config X86_SUPPORTS_MEMORY_FAILURE

bool

# MCE code calls memory_failure():

depends on X86_MCE

# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:

depends on !X86_NUMAQ

# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:

depends on X86_64 || !SPARSEMEM

select ARCH_SUPPORTS_MEMORY_FAILURE

default y

config X86_VISWS

bool "SGI 320/540 (Visual Workstation)"

depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT

depends on X86_32_NON_STANDARD

---help---

The SGI Visual Workstation series is an IA32-based workstation

based on SGI systems chips with some legacy PC hardware attached.

Say Y here to create a kernel to run on the SGI 320 or 540.

A kernel compiled for the Visual Workstation will run on general

PCs as well. See <file:Documentation/sgi-visws.txt> for details.

config X86_SUMMIT

bool "Summit/EXA (IBM x440)"

depends on X86_32_NON_STANDARD

---help---

This option is needed for IBM systems that use the Summit/EXA chipset.

In particular, it is needed for the x440.

config X86_ES7000

bool "Unisys ES7000 IA32 series"

depends on X86_32_NON_STANDARD && X86_BIGSMP

---help---

Support for Unisys ES7000 systems. Say 'Y' here if this kernel is

supposed to run on an IA32-based Unisys ES7000 system.

config SCHED_OMIT_FRAME_POINTER

def_bool y

prompt "Single-depth WCHAN output"

depends on X86

---help---

Calculate simpler /proc/<PID>/wchan values. If this option

is disabled then wchan values will recurse back to the

caller function. This provides more accurate wchan values,

at the expense of slightly more scheduling overhead.

If in doubt, say "Y".

menuconfig PARAVIRT_GUEST

bool "Paravirtualized guest support"

---help---

Say Y here to get to see options related to running Linux under

various hypervisors. This option alone does not add any kernel code.

If you say N, all options in this submenu will be skipped and disabled.

if PARAVIRT_GUEST

source "arch/x86/xen/Kconfig"

config VMI

bool "VMI Guest support (DEPRECATED)"

select PARAVIRT

depends on X86_32

---help---

VMI provides a paravirtualized interface to the VMware ESX server

(it could be used by other hypervisors in theory too, but is not

at the moment), by linking the kernel to a GPL-ed ROM module

provided by the hypervisor.

As of September 2009, VMware has started a phased retirement

of this feature from VMware's products. Please see

feature-removal-schedule.txt for details. If you are

planning to enable this option, please note that you cannot

live migrate a VMI enabled VM to a future VMware product,

which doesn't support VMI. So if you expect your kernel to

seamlessly migrate to newer VMware products, keep this

disabled.

config KVM_CLOCK

bool "KVM paravirtualized clock"

select PARAVIRT

select PARAVIRT_CLOCK

---help---

Turning on this option will allow you to run a paravirtualized clock

when running over the KVM hypervisor. Instead of relying on a PIT

(or probably other) emulation by the underlying device model, the host

provides the guest with timing infrastructure such as time of day, and

system time

config KVM_GUEST

bool "KVM Guest support"

select PARAVIRT

---help---

This option enables various optimizations for running under the KVM

hypervisor.

source "arch/x86/lguest/Kconfig"

config PARAVIRT

bool "Enable paravirtualization code"

---help---

This changes the kernel so it can modify itself when it is run

under a hypervisor, potentially improving performance significantly

over full virtualization. However, when run without a hypervisor

the kernel is theoretically slower and slightly larger.

config PARAVIRT_SPINLOCKS

bool "Paravirtualization layer for spinlocks"

depends on PARAVIRT && SMP && EXPERIMENTAL

---help---

Paravirtualized spinlocks allow a pvops backend to replace the

spinlock implementation with something virtualization-friendly

(for example, block the virtual CPU rather than spinning).

Unfortunately the downside is an up to 5% performance hit on

native kernels, with various workloads.

If you are unsure how to answer this question, answer N.

config PARAVIRT_CLOCK

bool

default n

endif

config PARAVIRT_DEBUG

bool "paravirt-ops debugging"

depends on PARAVIRT && DEBUG_KERNEL

---help---

Enable to debug paravirt_ops internals. Specifically, BUG if

a paravirt_op is missing when it is called.

config MEMTEST

bool "Memtest"

---help---

This option adds a kernel parameter 'memtest', which allows memtest

to be set.

memtest=0, mean disabled; -- default

memtest=1, mean do 1 test pattern;

...

memtest=4, mean do 4 test patterns.

If you are unsure how to answer this question, answer N.

config X86_SUMMIT_NUMA

def_bool y

depends on X86_32 && NUMA && X86_32_NON_STANDARD

config X86_CYCLONE_TIMER

def_bool y

depends on X86_32_NON_STANDARD

source "arch/x86/Kconfig.cpu"

config HPET_TIMER

def_bool X86_64

prompt "HPET Timer Support" if X86_32

---help---

Use the IA-PC HPET (High Precision Event Timer) to manage

time in preference to the PIT and RTC, if a HPET is

present.

HPET is the next generation timer replacing legacy 8254s.

The HPET provides a stable time base on SMP

systems, unlike the TSC, but it is more expensive to access,

as it is off-chip. You can find the HPET spec at

<http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.

You can safely choose Y here. However, HPET will only be

activated if the platform and the BIOS support this feature.

Otherwise the 8254 will be used for timing services.

Choose N to continue using the legacy 8254 timer.

config HPET_EMULATE_RTC

def_bool y

depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)

# Mark as embedded because too many people got it wrong.

# The code disables itself when not needed.

config DMI

default y

bool "Enable DMI scanning" if EMBEDDED

---help---

Enabled scanning of DMI to identify machine quirks. Say Y

here unless you have verified that your setup is not

affected by entries in the DMI blacklist. Required by PNP

BIOS code.

config GART_IOMMU

bool "GART IOMMU support" if EMBEDDED

default y

select SWIOTLB

depends on X86_64 && PCI

---help---

Support for full DMA access of devices with 32bit memory access only

on systems with more than 3GB. This is usually needed for USB,

sound, many IDE/SATA chipsets and some other devices.

Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART

based hardware IOMMU and a software bounce buffer based IOMMU used

on Intel systems and as fallback.

The code is only active when needed (enough memory and limited

device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified

too.

config CALGARY_IOMMU

bool "IBM Calgary IOMMU support"

select SWIOTLB

depends on X86_64 && PCI && EXPERIMENTAL

---help---

Support for hardware IOMMUs in IBM's xSeries x366 and x460

systems. Needed to run systems with more than 3GB of memory

properly with 32-bit PCI devices that do not support DAC

(Double Address Cycle). Calgary also supports bus level

isolation, where all DMAs pass through the IOMMU. This

prevents them from going anywhere except their intended

destination. This catches hard-to-find kernel bugs and

mis-behaving drivers and devices that do not use the DMA-API

properly to set up their DMA buffers. The IOMMU can be

turned off at boot time with the iommu=off parameter.

Normally the kernel will make the right choice by itself.

If unsure, say Y.

config CALGARY_IOMMU_ENABLED_BY_DEFAULT

def_bool y

prompt "Should Calgary be enabled by default?"

depends on CALGARY_IOMMU

---help---

Should Calgary be enabled by default? if you choose 'y', Calgary

will be used (if it exists). If you choose 'n', Calgary will not be

used even if it exists. If you choose 'n' and would like to use

Calgary anyway, pass 'iommu=calgary' on the kernel command line.

If unsure, say Y.

config AMD_IOMMU

bool "AMD IOMMU support"

select SWIOTLB

select PCI_MSI

depends on X86_64 && PCI && ACPI

---help---

With this option you can enable support for AMD IOMMU hardware in

your system. An IOMMU is a hardware component which provides

remapping of DMA memory accesses from devices. With an AMD IOMMU you

can isolate the the DMA memory of different devices and protect the

system from misbehaving device drivers or hardware.

You can find out if your system has an AMD IOMMU if you look into

your BIOS for an option to enable it or if you have an IVRS ACPI

table.

config AMD_IOMMU_STATS

bool "Export AMD IOMMU statistics to debugfs"

depends on AMD_IOMMU

select DEBUG_FS

---help---

This option enables code in the AMD IOMMU driver to collect various

statistics about whats happening in the driver and exports that

information to userspace via debugfs.

If unsure, say N.

# need this always selected by IOMMU for the VIA workaround

config SWIOTLB

def_bool y if X86_64

---help---

Support for software bounce buffers used on x86-64 systems

which don't have a hardware IOMMU (e.g. the current generation

of Intel's x86-64 CPUs). Using this PCI devices which can only

access 32-bits of memory can be used on systems with more than

3 GB of memory. If unsure, say Y.

config IOMMU_HELPER

def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)

config IOMMU_API

def_bool (AMD_IOMMU || DMAR)

config MAXSMP

bool "Configure Maximum number of SMP Processors and NUMA Nodes"

depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL

select CPUMASK_OFFSTACK

default n

---help---

Configure maximum number of CPUS and NUMA Nodes for this architecture.

If unsure, say N.

config NR_CPUS

int "Maximum number of CPUs" if SMP && !MAXSMP

range 2 8 if SMP && X86_32 && !X86_BIGSMP

range 2 512 if SMP && !MAXSMP

default "1" if !SMP

default "4096" if MAXSMP

default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)

default "8" if SMP

---help---

This allows you to specify the maximum number of CPUs which this

kernel will support. The maximum supported value is 512 and the

minimum value which makes sense is 2.

This is purely to save memory - each supported CPU adds

approximately eight kilobytes to the kernel image.

config SCHED_SMT

bool "SMT (Hyperthreading) scheduler support"

depends on X86_HT

---help---

SMT scheduler support improves the CPU scheduler's decision making

when dealing with Intel Pentium 4 chips with HyperThreading at a

cost of slightly increased overhead in some places. If unsure say

N here.

config SCHED_MC

def_bool y

prompt "Multi-core scheduler support"

depends on X86_HT

---help---

Multi-core scheduler support improves the CPU scheduler's decision

making when dealing with multi-core CPU chips at a cost of slightly

increased overhead in some places. If unsure say N here.

source "kernel/Kconfig.preempt"

config X86_UP_APIC

bool "Local APIC support on uniprocessors"

depends on X86_32 && !SMP && !X86_32_NON_STANDARD

---help---

A local APIC (Advanced Programmable Interrupt Controller) is an

integrated interrupt controller in the CPU. If you have a single-CPU

system which has a processor with a local APIC, you can say Y here to

enable and use it. If you say Y here even though your machine doesn't

have a local APIC, then the kernel will still run with no slowdown at

all. The local APIC supports CPU-generated self-interrupts (timer,

performance counters), and the NMI watchdog which detects hard

lockups.

config X86_UP_IOAPIC

bool "IO-APIC support on uniprocessors"

depends on X86_UP_APIC

---help---

An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an

SMP-capable replacement for PC-style interrupt controllers. Most

SMP systems and many recent uniprocessor systems have one.

If you have a single-CPU system with an IO-APIC, you can say Y here

to use it. If you say Y here even though your machine doesn't have

an IO-APIC, then the kernel will still run with no slowdown at all.

config X86_LOCAL_APIC

def_bool y

depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC

config X86_IO_APIC

def_bool y

depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC

config X86_VISWS_APIC

def_bool y

depends on X86_32 && X86_VISWS

config X86_REROUTE_FOR_BROKEN_BOOT_IRQS

bool "Reroute for broken boot IRQs"

default n

depends on X86_IO_APIC

---help---

This option enables a workaround that fixes a source of

spurious interrupts. This is recommended when threaded

interrupt handling is used on systems where the generation of

superfluous "boot interrupts" cannot be disabled.

Some chipsets generate a legacy INTx "boot IRQ" when the IRQ

entry in the chipset's IO-APIC is masked (as, e.g. the RT

kernel does during interrupt handling). On chipsets where this

boot IRQ generation cannot be disabled, this workaround keeps

the original IRQ line masked so that only the equivalent "boot

IRQ" is delivered to the CPUs. The workaround also tells the

kernel to set up the IRQ handler on the boot IRQ line. In this

way only one interrupt is delivered to the kernel. Otherwise

the spurious second interrupt may cause the kernel to bring

down (vital) interrupt lines.

Only affects "broken" chipsets. Interrupt sharing may be

increased on these systems.

config X86_MCE

bool "Machine Check / overheating reporting"

---help---

Machine Check support allows the processor to notify the

kernel if it detects a problem (e.g. overheating, data corruption).

The action the kernel takes depends on the severity of the problem,

ranging from warning messages to halting the machine.

config X86_MCE_INTEL

def_bool y

prompt "Intel MCE features"

depends on X86_MCE && X86_LOCAL_APIC

---help---

Additional support for intel specific MCE features such as

the thermal monitor.

config X86_MCE_AMD

def_bool y

prompt "AMD MCE features"

depends on X86_MCE && X86_LOCAL_APIC

---help---

Additional support for AMD specific MCE features such as

the DRAM Error Threshold.

config X86_ANCIENT_MCE

def_bool n

depends on X86_32 && X86_MCE

prompt "Support for old Pentium 5 / WinChip machine checks"

---help---

Include support for machine check handling on old Pentium 5 or WinChip

systems. These typically need to be enabled explicitely on the command

line.

config X86_MCE_THRESHOLD

depends on X86_MCE_AMD || X86_MCE_INTEL

bool

default y

config X86_MCE_INJECT

depends on X86_MCE

tristate "Machine check injector support"

---help---

Provide support for injecting machine checks for testing purposes.

If you don't know what a machine check is and you don't do kernel

QA it is safe to say n.

config X86_THERMAL_VECTOR

def_bool y

depends on X86_MCE_INTEL

config VM86

bool "Enable VM86 support" if EMBEDDED

default y

depends on X86_32

---help---

This option is required by programs like DOSEMU to run 16-bit legacy

code on X86 processors. It also may be needed by software like

XFree86 to initialize some video cards via BIOS. Disabling this

option saves about 6k.

config TOSHIBA

tristate "Toshiba Laptop support"

depends on X86_32

---help---

This adds a driver to safely access the System Management Mode of

the CPU on Toshiba portables with a genuine Toshiba BIOS. It does

not work on models with a Phoenix BIOS. The System Management Mode

is used to set the BIOS and power saving options on Toshiba portables.

For information on utilities to make use of this driver see the

Toshiba Linux utilities web site at:

<http://www.buzzard.org.uk/toshiba/>.

Say Y if you intend to run this kernel on a Toshiba portable.

Say N otherwise.

config I8K

tristate "Dell laptop support"

---help---

This adds a driver to safely access the System Management Mode

of the CPU on the Dell Inspiron 8000. The System Management Mode

is used to read cpu temperature and cooling fan status and to

control the fans on the I8K portables.

This driver has been tested only on the Inspiron 8000 but it may

also work with other Dell laptops. You can force loading on other

models by passing the parameter `force=1' to the module. Use at

your own risk.

For information on utilities to make use of this driver see the

I8K Linux utilities web site at:

<http://people.debian.org/~dz/i8k/>

Say Y if you intend to run this kernel on a Dell Inspiron 8000.

Say N otherwise.

config X86_REBOOTFIXUPS

bool "Enable X86 board specific fixups for reboot"

depends on X86_32

---help---

This enables chipset and/or board specific fixups to be done

in order to get reboot to work correctly. This is only needed on

some combinations of hardware and BIOS. The symptom, for which

this config is intended, is when reboot ends with a stalled/hung

system.

Currently, the only fixup is for the Geode machines using

CS5530A and CS5536 chipsets and the RDC R-321x SoC.

Say Y if you want to enable the fixup. Currently, it's safe to

enable this option even if you don't need it.

Say N otherwise.

config MICROCODE

tristate "/dev/cpu/microcode - microcode support"

select FW_LOADER

---help---

If you say Y here, you will be able to update the microcode on

certain Intel and AMD processors. The Intel support is for the

IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,

Pentium 4, Xeon etc. The AMD support is for family 0x10 and

0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.

You will obviously need the actual microcode binary data itself

which is not shipped with the Linux kernel.

This option selects the general module only, you need to select

at least one vendor specific module as well.

To compile this driver as a module, choose M here: the

module will be called microcode.

config MICROCODE_INTEL

bool "Intel microcode patch loading support"

depends on MICROCODE

default MICROCODE

select FW_LOADER

---help---

This options enables microcode patch loading support for Intel

processors.

For latest news and information on obtaining all the required

Intel ingredients for this driver, check:

<http://www.urbanmyth.org/microcode/>.

config MICROCODE_AMD

bool "AMD microcode patch loading support"

depends on MICROCODE

select FW_LOADER

---help---

If you select this option, microcode patch loading support for AMD

processors will be enabled.

config MICROCODE_OLD_INTERFACE

def_bool y

depends on MICROCODE

config X86_MSR

tristate "/dev/cpu/*/msr - Model-specific register support"

---help---

This device gives privileged processes access to the x86

Model-Specific Registers (MSRs). It is a character device with

major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.

MSR accesses are directed to a specific CPU on multi-processor

systems.

config X86_CPUID

tristate "/dev/cpu/*/cpuid - CPU information support"

---help---

This device gives processes access to the x86 CPUID instruction to

be executed on a specific processor. It is a character device

with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to

/dev/cpu/31/cpuid.

config X86_CPU_DEBUG

tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"

---help---

If you select this option, this will provide various x86 CPUs

information through debugfs.

choice

prompt "High Memory Support"

default HIGHMEM4G if !X86_NUMAQ

default HIGHMEM64G if X86_NUMAQ