path: root/arch/x86_64/Kconfig

#
# For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt.
#
# Note: ISA is disabled and will hopefully never be enabled.
# If you managed to buy an ISA x86-64 box you'll have to fix all the
# ISA drivers you need yourself.
#

mainmenu "Linux Kernel Configuration"

config X86_64
	bool
	default y
	help
	  Port to the x86-64 architecture. x86-64 is a 64-bit extension to the
	  classical 32-bit x86 architecture. For details see
	  <http://www.x86-64.org/>.

config 64BIT
	def_bool y

config X86
	bool
	default y

config ZONE_DMA32
	bool
	default y

config LOCKDEP_SUPPORT
	bool
	default y

config STACKTRACE_SUPPORT
	bool
	default y

config SEMAPHORE_SLEEPERS
	bool
	default y

config MMU
	bool
	default y

config ISA
	bool

config SBUS
	bool

config RWSEM_GENERIC_SPINLOCK
	bool
	default y

config RWSEM_XCHGADD_ALGORITHM
	bool

config GENERIC_HWEIGHT
	bool
	default y

config GENERIC_CALIBRATE_DELAY
	bool
	default y

config X86_CMPXCHG
	bool
	default y

config EARLY_PRINTK
	bool
	default y

config GENERIC_ISA_DMA
	bool
	default y

config GENERIC_IOMAP
	bool
	default y

config ARCH_MAY_HAVE_PC_FDC
	bool
	default y

config ARCH_POPULATES_NODE_MAP
	def_bool y

config DMI
	bool
	default y

config AUDIT_ARCH
	bool
	default y

source "init/Kconfig"


menu "Processor type and features"

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_VSMP
	bool "Support for ScaleMP vSMP"
	depends on 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

choice
	prompt "Processor family"
	default MK8

config MK8
	bool "AMD-Opteron/Athlon64"
	help
	  Optimize for AMD Opteron/Athlon64/Hammer/K8 CPUs.

config MPSC
       bool "Intel EM64T"
       help
	  Optimize for Intel Pentium 4 and Xeon CPUs with Intel
	  Extended Memory 64 Technology(EM64T). For details see
	  <http://www.intel.com/technology/64bitextensions/>.

config GENERIC_CPU
	bool "Generic-x86-64"
	help
	  Generic x86-64 CPU.

endchoice

#
# Define implied options from the CPU selection here
#
config X86_L1_CACHE_BYTES
	int
	default "128" if GENERIC_CPU || MPSC
	default "64" if MK8

config X86_L1_CACHE_SHIFT
	int
	default "7" if GENERIC_CPU || MPSC
	default "6" if MK8

config X86_INTERNODE_CACHE_BYTES
	int
	default "4096" if X86_VSMP
	default X86_L1_CACHE_BYTES if !X86_VSMP

config X86_TSC
	bool
	default y

config X86_GOOD_APIC
	bool
	default y

config MICROCODE
	tristate "/dev/cpu/microcode - Intel CPU microcode support"
	select FW_LOADER
	---help---
	  If you say Y here the 'File systems' section, you will be
	  able to update the microcode on Intel processors. 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:
	  <http://www.urbanmyth.org/microcode/>.

	  To compile this driver as a module, choose M here: the
	  module will be called microcode.
	  If you use modprobe or kmod you may also want to add the line
	  'alias char-major-10-184 microcode' to your /etc/modules.conf file.

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.

config X86_HT
	bool
	depends on SMP && !MK8
	default y

config MATH_EMULATION
	bool

config MCA
	bool

config EISA
	bool

config X86_IO_APIC
	bool
	default y

config X86_LOCAL_APIC
	bool
	default y

config MTRR
	bool "MTRR (Memory Type Range Register) support"
	---help---
	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
	  the Memory Type Range Registers (MTRRs) may be used to control
	  processor access to memory ranges. This is most useful if you have
	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
	  allows bus write transfers to be combined into a larger transfer
	  before bursting over the PCI/AGP bus. This can increase performance
	  of image write operations 2.5 times or more. Saying Y here creates a
	  /proc/mtrr file which may be used to manipulate your processor's
	  MTRRs. Typically the X server should use this.

	  This code has a reasonably generic interface so that similar
	  control registers on other processors can be easily supported
	  as well.

	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
	  can lead to all sorts of problems, so it's good to say Y here.

	  Just say Y here, all x86-64 machines support MTRRs.

	  See <file:Documentation/mtrr.txt> for more information.

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.

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

config SCHED_SMT
	bool "SMT (Hyperthreading) scheduler support"
	depends on SMP
	default n
	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 SMP
	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 NUMA
       bool "Non Uniform Memory Access (NUMA) Support"
       depends on SMP
       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.
	 This code is recommended on all multiprocessor Opteron systems.
	 If the system is EM64T, you should say N unless your system is EM64T 
	 NUMA. 

config K8_NUMA
       bool "Old style AMD Opteron NUMA detection"
       depends on 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 configurtion 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 NODES_SHIFT
	int
	default "6"
	depends on NEED_MULTIPLE_NODES

# Dummy CONFIG option to select ACPI_NUMA from drivers/acpi/Kconfig.

config X86_64_ACPI_NUMA
       bool "ACPI NUMA detection"
       depends on NUMA
       select ACPI 
	select PCI
       select ACPI_NUMA
       default y
       help
	 Enable ACPI SRAT based node topology detection.

config NUMA_EMU
	bool "NUMA emulation"
	depends on 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 ARCH_DISCONTIGMEM_ENABLE
       bool
       depends on NUMA
       default y


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)

config ARCH_MEMORY_PROBE
	def_bool y
	depends on MEMORY_HOTPLUG

config ARCH_FLATMEM_ENABLE
	def_bool y
	depends on !NUMA

source "mm/Kconfig"

config MEMORY_HOTPLUG_RESERVE
	def_bool y
	depends on (MEMORY_HOTPLUG && DISCONTIGMEM)

config HAVE_ARCH_EARLY_PFN_TO_NID
	def_bool y
	depends on NUMA

config OUT_OF_LINE_PFN_TO_PAGE
	def_bool y
	depends on DISCONTIGMEM

config NR_CPUS
	int "Maximum number of CPUs (2-256)"
	range 2 255
	depends on SMP
	default "8"
	help
	  This allows you to specify the maximum number of CPUs which this
	  kernel will support. Current maximum is 256 CPUs due to
	  APIC addressing limits. Less depending on the hardware.

	  This is purely to save memory - each supported CPU requires
	  memory in the static kernel configuration.

config HOTPLUG_CPU
	bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
	depends on SMP && HOTPLUG && EXPERIMENTAL
	help
		Say Y here to experiment with turning CPUs off and on.  CPUs
		can be controlled through /sys/devices/system/cpu/cpu#.
		Say N if you want to disable CPU hotplug.

config ARCH_ENABLE_MEMORY_HOTPLUG
	def_bool y

config HPET_TIMER
	bool
	default y
	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.  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.htm>.

config HPET_EMULATE_RTC
	bool "Provide RTC interrupt"
	depends on HPET_TIMER && RTC=y

# Mark as embedded because too many people got it wrong.
# The code disables itself when not needed.
config IOMMU
	bool "IOMMU support" if EMBEDDED
	default y
	select SWIOTLB
	select AGP
	depends on 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 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 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.

# need this always selected by IOMMU for the VIA workaround
config SWIOTLB
	bool

config X86_MCE
	bool "Machine check support" if EMBEDDED
	default y
	help
	   Include a machine check error handler to report hardware errors.
	   This version will require the mcelog utility to decode some
	   machine check error logs. See
	   ftp://ftp.x86-64.org/pub/linux/tools/mcelog

config X86_MCE_INTEL
	bool "Intel MCE features"
	depends on 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_MCE && X86_LOCAL_APIC
	default y
	help
	   Additional support for AMD specific MCE features such as
	   the DRAM Error Threshold.

config KEXEC
	bool "kexec system call"
	help
	  kexec is a system call that implem