Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

# 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

        bool

        default y

config GENERIC_TIME

        bool

        default y

config GENERIC_CMOS_UPDATE

        bool

        default y

config CLOCKSOURCE_WATCHDOG

        bool

        default y

config GENERIC_CLOCKEVENTS

        bool

        default y

config GENERIC_CLOCKEVENTS_BROADCAST

        bool

        default y

        depends on X86_64 || (X86_32 && X86_LOCAL_APIC)

config LOCKDEP_SUPPORT

        bool

        default y

config STACKTRACE_SUPPORT

        bool

        default y

config SEMAPHORE_SLEEPERS

        bool

        default y

config MMU

        bool

        default y

config ZONE_DMA

        bool

        default y

config QUICKLIST

        bool

        default X86_32

config SBUS

        bool

config GENERIC_ISA_DMA

        bool

        default y

config GENERIC_IOMAP

        bool

        default y

config GENERIC_BUG

        bool

        default y

        depends on BUG

config GENERIC_HWEIGHT

        bool

        default y

config ARCH_MAY_HAVE_PC_FDC

        bool

        default y

config DMI

        bool

        default y

config RWSEM_GENERIC_SPINLOCK

        def_bool !X86_XADD

config RWSEM_XCHGADD_ALGORITHM

        def_bool X86_XADD

config ARCH_HAS_ILOG2_U32

        def_bool n

config ARCH_HAS_ILOG2_U64

        def_bool n

config GENERIC_CALIBRATE_DELAY

        def_bool y

config GENERIC_TIME_VSYSCALL

        bool

        default X86_64

config ARCH_SUPPORTS_OPROFILE

        bool

        default y

config ZONE_DMA32

        bool

        default X86_64

config ARCH_POPULATES_NODE_MAP

        def_bool y

config AUDIT_ARCH

        bool

        default X86_64

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

config GENERIC_HARDIRQS

        bool

        default y

config GENERIC_IRQ_PROBE

        bool

        default y

config GENERIC_PENDING_IRQ

        bool

        depends on GENERIC_HARDIRQS && SMP

        default y

config X86_SMP

        bool

        depends on X86_32 && SMP && !X86_VOYAGER

        default y

config X86_HT

        bool

        depends on SMP

        depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || (X86_64 && !MK8)

        default y

config X86_BIOS_REBOOT

        bool

        depends on X86_32 && !(X86_VISWS || X86_VOYAGER)

        default y

config X86_TRAMPOLINE

        bool

        depends on X86_SMP || (X86_VOYAGER && SMP)

        default y

config KTIME_SCALAR

        def_bool X86_32

source "init/Kconfig"

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 the ,

          ,

           and the SMP-HOWTO available at

          .

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

choice

        prompt "Subarchitecture Type"

        default X86_PC

config X86_PC

        bool "PC-compatible"

        help

          Choose this option if your computer is a standard PC or compatible.

config X86_ELAN

        bool "AMD Elan"

        depends on X86_32

        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_VOYAGER

        bool "Voyager (NCR)"

        depends on X86_32

        select SMP if !BROKEN

        help

          Voyager is an MCA-based 32-way capable SMP architecture proprietary

          to NCR Corp.  Machine classes 345x/35xx/4100/51xx are Voyager-based.

          *** WARNING ***

          If you do not specifically know you have a Voyager based machine,

          say N here, otherwise the kernel you build will not be bootable.

config X86_NUMAQ

        bool "NUMAQ (IBM/Sequent)"

        select SMP

        select NUMA

        depends on X86_32

        help

          This option is used for getting Linux to run on a (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 .

config X86_SUMMIT

        bool "Summit/EXA (IBM x440)"

        depends on X86_32 && SMP

        help

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

          In particular, it is needed for the x440.

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

          If you want to build a NUMA kernel, you must select ACPI.

config X86_BIGSMP

        bool "Support for other sub-arch 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

          and if the system is not of any sub-arch type above.

          If you don't have such a system, you should say N here.

config X86_VISWS

        bool "SGI 320/540 (Visual Workstation)"

        depends on X86_32

        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 not run on PCs

          and vice versa. See  for details.

config X86_GENERICARCH

       bool "Generic architecture (Summit, bigsmp, ES7000, default)"

        depends on X86_32

       help

          This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.

          It is intended for a generic binary kernel.

          If you want a NUMA kernel, select ACPI.   We need SRAT for NUMA.

config X86_ES7000

        bool "Support for Unisys ES7000 IA32 series"

        depends on X86_32 && SMP

        help

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

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

          Only choose this option if you have such a system, otherwise you

          should say N here.

config X86_VSMP

        bool "Support for ScaleMP vSMP"

        depends on X86_64 && PCI

         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.

endchoice

config SCHED_NO_NO_OMIT_FRAME_POINTER

        bool "Single-depth WCHAN output"

        default y

        depends on X86_32

        help

          Calculate simpler /proc//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".

config PARAVIRT

        bool

        depends on X86_32 && !(X86_VISWS || X86_VOYAGER)

        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.

menuconfig PARAVIRT_GUEST

        bool "Paravirtualized guest support"

        depends on X86_32

        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"

        select PARAVIRT

        depends on !(X86_VISWS || X86_VOYAGER)

        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.

source "arch/x86/lguest/Kconfig"

endif

config ACPI_SRAT

        bool

        default y

        depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)

        select ACPI_NUMA

config HAVE_ARCH_PARSE_SRAT

       bool

       default y

       depends on ACPI_SRAT

config X86_SUMMIT_NUMA

        bool

        default y

        depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)

config X86_CYCLONE_TIMER

        bool

        default y

        depends on X86_32 && X86_SUMMIT || X86_GENERICARCH

config ES7000_CLUSTERED_APIC

        bool

        default y

        depends on SMP && X86_ES7000 && MPENTIUMIII

source "arch/x86/Kconfig.cpu"

config HPET_TIMER

        bool

        prompt "HPET Timer Support" if X86_32

        default X86_64

        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

         .

         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

        bool

        depends on HPET_TIMER && RTC=y

        default y

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

# The code disables itself when not needed.

config GART_IOMMU

        bool "GART IOMMU support" if EMBEDDED

        default y

        select SWIOTLB

        select AGP

        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

        bool "Should Calgary be enabled by default?"

        default y

        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.

# need this always selected by IOMMU for the VIA workaround

config SWIOTLB

        bool

        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 NR_CPUS

        int "Maximum number of CPUs (2-255)"

        range 2 255

        depends on SMP

        default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000

        default "8"

        help

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

          kernel will support.  The maximum supported value is 255 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_64 && SMP) || (X86_32 && 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

        bool "Multi-core scheduler support"

        depends on (X86_64 && SMP) || (X86_32 && X86_HT)

        default y

        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_VISWS || X86_VOYAGER || X86_GENERICARCH)

        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

        bool

        depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))

        default y

config X86_IO_APIC

        bool

        depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))

        default y

config X86_VISWS_APIC

        bool

        depends on X86_32 && X86_VISWS

        default y

config X86_MCE

        bool "Machine Check Exception"

        depends on !X86_VOYAGER

        ---help---

          Machine Check Exception support allows the processor to notify the

          kernel if it detects a problem (e.g. overheating, component failure).

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

          ranging from a warning message on the console, to halting the machine.

          Your processor must be a Pentium or newer to support this - check the

          flags in /proc/cpuinfo for mce.  Note that some older Pentium systems

          have a design flaw which leads to false MCE events - hence MCE is

          disabled on all P5 processors, unless explicitly enabled with "mce"

          as a boot argument.  Similarly, if MCE is built in and creates a

          problem on some new non-standard machine, you can boot with "nomce"

          to disable it.  MCE support simply ignores non-MCE processors like

          the 386 and 486, so nearly everyone can say Y here.

config X86_MCE_INTEL

        bool "Intel MCE features"

        depends on X86_64 && X86_MCE && X86_LOCAL_APIC

        default y

        help

           Additional support for intel specific MCE features such as

           the thermal monitor.

config X86_MCE_AMD

        bool "AMD MCE features"

        depends on X86_64 && X86_MCE && X86_LOCAL_APIC

        default y

        help

           Additional support for AMD specific MCE features such as

           the DRAM Error Threshold.

config X86_MCE_NONFATAL

        tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"

        depends on X86_32 && X86_MCE

        help

          Enabling this feature starts a timer that triggers every 5 seconds which

          will look at the machine check registers to see if anything happened.

          Non-fatal problems automatically get corrected (but still logged).

          Disable this if you don't want to see these messages.

          Seeing the messages this option prints out may be indicative of dying

          or out-of-spec (ie, overclocked) hardware.

          This option only does something on certain CPUs.

          (AMD Athlon/Duron and Intel Pentium 4)

config X86_MCE_P4THERMAL

        bool "check for P4 thermal throttling interrupt."

        depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS

        help

          Enabling this feature will cause a message to be printed when the P4

          enters thermal throttling.

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:

          .

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

          Say N otherwise.

config I8K

        tristate "Dell laptop support"

        depends on X86_32

        ---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:

          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 && X86

        default n

        ---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.

          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 - Intel IA32 CPU microcode support"

        select FW_LOADER

        ---help---

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

          Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,

          Pentium III, Pentium 4, Xeon etc.  You will obviously need the

          actual microcode binary data itself which is not shipped with the

          Linux kernel.

          For latest news and information on obtaining all the required

          ingredients for this driver, check:

          .

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

          module will be called microcode.

config MICROCODE_OLD_INTERFACE

        bool

        depends on MICROCODE

        default y

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.

choice

        prompt "High Memory Support"

        default HIGHMEM4G if !X86_NUMAQ

        default HIGHMEM64G if X86_NUMAQ

        depends on X86_32

config NOHIGHMEM

        bool "off"

        depends on !X86_NUMAQ

        ---help---

          Linux can use up to 64 Gigabytes of physical memory on x86 systems.

          However, the address space of 32-bit x86 processors is only 4

          Gigabytes large. That means that, if you have a large amount of

          physical memory, not all of it can be "permanently mapped" by the

          kernel. The physical memory that's not permanently mapped is called

          "high memory".

          If you are compiling a kernel which will never run on a machine with

          more than 1 Gigabyte total physical RAM, answer "off" here (default

          choice and suitable for most users). This will result in a "3GB/1GB"

          split: 3GB are mapped so that each process sees a 3GB virtual memory

          space and the remaining part of the 4GB virtual memory space is used

          by the kernel to permanently map as much physical memory as

          possible.

          If the machine has between 1 and 4 Gigabytes physical RAM, then

          answer "4GB" here.

          If more than 4 Gigabytes is used then answer "64GB" here. This

          selection turns Intel PAE (Physical Address Extension) mode on.

          PAE implements 3-level paging on IA32 processors. PAE is fully

          supported by Linux, PAE mode is implemented on all recent Intel

          processors (Pentium Pro and better). NOTE: If you say "64GB" here,

          then the kernel will not boot on CPUs that don't support PAE!

          The actual amount of total physical memory will either be

          auto detected or can be forced by using a kernel command line option

          such as "mem=256M". (Try "man bootparam" or see the documentation of

          your boot loader (lilo or loadlin) about how to pass options to the

          kernel at boot time.)

          If unsure, say "off".

config HIGHMEM4G

        bool "4GB"

        depends on !X86_NUMAQ

        help

          Select this if you have a 32-bit processor and between 1 and 4

          gigabytes of physical RAM.

config HIGHMEM64G

        bool "64GB"

        depends on !M386 && !M486

        select X86_PAE

        help

          Select this if you have a 32-bit processor and more than 4

          gigabytes of physical RAM.

endchoice

choice

        depends on EXPERIMENTAL

        prompt "Memory split" if EMBEDDED

        default VMSPLIT_3G

        depends on X86_32

        help

          Select the desired split between kernel and user memory.

          If the address range available to the kernel is less than the

          physical memory installed, the remaining memory will be available

          as "high memory". Accessing high memory is a little more costly

          than low memory, as it needs to be mapped into the kernel first.

          Note that increasing the kernel address space limits the range

          available to user programs, making the address space there

          tighter.  Selecting anything other than the default 3G/1G split

          will also likely make your kernel incompatible with binary-only

          kernel modules.

          If you are not absolutely sure what you are doing, leave this

          option alone!

        config VMSPLIT_3G

                bool "3G/1G user/kernel split"

        config VMSPLIT_3G_OPT

                depends on !X86_PAE

                bool "3G/1G user/kernel split (for full 1G low memory)"

        config VMSPLIT_2G

                bool "2G/2G user/kernel split"

        config VMSPLIT_2G_OPT

                depends on !X86_PAE

                bool "2G/2G user/kernel split (for full 2G low memory)"

        config VMSPLIT_1G

                bool "1G/3G user/kernel split"

endchoice

config PAGE_OFFSET

        hex

        default 0xB0000000 if VMSPLIT_3G_OPT

        default 0x80000000 if VMSPLIT_2G

        default 0x78000000 if VMSPLIT_2G_OPT

        default 0x40000000 if VMSPLIT_1G

        default 0xC0000000

        depends on X86_32

config HIGHMEM

        bool

        depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)

        default y

config X86_PAE

        bool "PAE (Physical Address Extension) Support"

        default n

        depends on X86_32 && !HIGHMEM4G

        select RESOURCES_64BIT

        help

          PAE is required for NX support, and furthermore enables

          larger swapspace support for non-overcommit purposes. It

          has the cost of more pagetable lookup overhead, and also

          consumes more pagetable space per process.

# Common NUMA Features

config NUMA

        bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"

        depends on SMP

        depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)

        default n if X86_PC

        default y if (X86_NUMAQ || X86_SUMMIT)

        help

          Enable NUMA (Non Uniform Memory Access) support.

          The kernel will try to allocate memory used by a CPU on the

          local memory controller of the CPU and add some more

          NUMA awareness to the kernel.

          For i386 this is currently highly experimental and should be only

          used for kernel development. It might also cause boot failures.

          For x86_64 this is recommended on all multiprocessor Opteron systems.

          If the system is EM64T, you should say N unless your system is

          EM64T NUMA.

comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"

        depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)

config K8_NUMA

       bool "Old style AMD Opteron NUMA detection"

       depends on X86_64 && NUMA && PCI

       default y

       help

         Enable K8 NUMA node topology detection.  You should say Y here if

         you have a multi processor AMD K8 system. This uses an old

         method to read the NUMA configuration directly from the builtin

         Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA

         instead, which also takes priority if both are compiled in.

config X86_64_ACPI_NUMA

        bool "ACPI NUMA detection"

        depends on X86_64 && NUMA && ACPI && PCI

        select ACPI_NUMA

        default y

        help

          Enable ACPI SRAT based node topology detection.

config NUMA_EMU

        bool "NUMA emulation"

        depends on X86_64 && NUMA

        help

          Enable NUMA emulation. A flat machine will be split

          into virtual nodes when booted with "numa=fake=N", where N is the

          number of nodes. This is only useful for debugging.

config NODES_SHIFT

        int

        default "6" if X86_64

        default "4" if X86_NUMAQ

        default "3"

        depends on NEED_MULTIPLE_NODES

config HAVE_ARCH_BOOTMEM_NODE

        bool

        depends on X86_32 && NUMA

        default y

config ARCH_HAVE_MEMORY_PRESENT

        bool

        depends on X86_32 && DISCONTIGMEM

        default y

config NEED_NODE_MEMMAP_SIZE

        bool

        depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)

        default y

config HAVE_ARCH_ALLOC_REMAP

        bool

        depends on X86_32 && NUMA

        default y

config ARCH_FLATMEM_ENABLE

        def_bool y

        depends on (X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC) || (X86_64 && !NUMA)

config ARCH_DISCONTIGMEM_ENABLE

        def_bool y

        depends on NUMA

config ARCH_DISCONTIGMEM_DEFAULT

        def_bool y

        depends on NUMA

config ARCH_SPARSEMEM_ENABLE

        def_bool y

        depends on NUMA || (EXPERIMENTAL && (X86_PC || X86_64))

        select SPARSEMEM_STATIC if X86_32

        select SPARSEMEM_VMEMMAP_ENABLE if X86_64

config ARCH_SELECT_MEMORY_MODEL

        def_bool y

        depends on X86_32 && ARCH_SPARSEMEM_ENABLE

config ARCH_MEMORY_PROBE

        def_bool X86_64

        depends on MEMORY_HOTPLUG

source "mm/Kconfig"

config HIGHPTE

        bool "Allocate 3rd-level pagetables from highmem"

        depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)

        help

          The VM uses one page table entry for each page of physical memory.

          For systems with a lot of RAM, this can be wasteful of precious

          low memory.  Setting this option will put user-space page table

          entries in high memory.

config MATH_EMULATION

        bool

        prompt "Math emulation" if X86_32

        ---help---

          Linux can emulate a math coprocessor (used for floating point

          operations) if you don't have one. 486DX and Pentium processors have

          a math coprocessor built in, 486SX and 386 do not, unless you added

          a 487DX or 387, respectively. (The messages during boot time can

          give you some hints here ["man dmesg"].) Everyone needs either a

          coprocessor or this emulation.