arch/x86_64/Kconfig - kernel/msm - Gitiles

 #
 # 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 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 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"
 	 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"
 	---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 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
        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 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"
 	default y
 	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 (EXPERIMENTAL)"
 	depends on EXPERIMENTAL
 	help
 	  kexec is a system call that implements the ability to shutdown your
 	  current kernel, and to start another kernel.  It is like a reboot
 	  but it is independent of the system firmware.   And like a reboot
 	  you can start any kernel with it, not just Linux.

 	  The name comes from the similarity to the exec system call.

 	  It is an ongoing process to be certain the hardware in a machine
 	  is properly shutdown, so do not be surprised if this code does not
 	  initially work for you.  It may help to enable device hotplugging
 	  support.  As of this writing the exact hardware interface is
 	  strongly in flux, so no good recommendation can be made.

 config CRASH_DUMP
 	bool "kernel crash dumps (EXPERIMENTAL)"
 	depends on EXPERIMENTAL
 	help
 		Generate crash dump after being started by kexec.

 config PHYSICAL_START
 	hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
 	default "0x1000000" if CRASH_DUMP
 	default "0x200000"
 	help
 	  This gives the physical address where the kernel is loaded. Normally
 	  for regular kernels this value is 0x200000 (2MB). But in the case
 	  of kexec on panic the fail safe kernel needs to run at a different
 	  address than the panic-ed kernel. This option is used to set the load
 	  address for kernels used to capture crash dump on being kexec'ed
 	  after panic. The default value for crash dump kernels is
 	  0x1000000 (16MB). This can also be set based on the "X" value as
 	  specified in the "crashkernel=YM@XM" command line boot parameter
 	  passed to the panic-ed kernel. Typically this parameter is set as
 	  crashkernel=64M@16M. Please take a look at
 	  Documentation/kdump/kdump.txt for more details about crash dumps.

 	  Don't change this unless you know what you are doing.

 config SECCOMP
 	bool "Enable seccomp to safely compute untrusted bytecode"
 	depends on PROC_FS
 	default y
 	help
 	  This kernel feature is useful for number crunching applications
 	  that may need to compute untrusted bytecode during their
 	  execution. By using pipes or other transports made available to
 	  the process as file descriptors supporting the read/write
 	  syscalls, it's possible to isolate those applications in
 	  their own address space using seccomp. Once seccomp is
 	  enabled via /proc/<pid>/seccomp, it cannot be disabled
 	  and the task is only allowed to execute a few safe syscalls
 	  defined by each seccomp mode.

 	  If unsure, say Y. Only embedded should say N here.

 source kernel/Kconfig.hz

 config REORDER
 	bool "Function reordering"
 	default n
 	help
          This option enables the toolchain to reorder functions for a more
          optimal TLB usage. If you have pretty much any version of binutils,
 	 this can increase your kernel build time by roughly one minute.

 config K8_NB
 	def_bool y
 	depends on AGP_AMD64 || IOMMU || (PCI && NUMA)

 endmenu

 #
 # Use the generic interrupt handling code in kernel/irq/:
 #
 config GENERIC_HARDIRQS
 	bool
 	default y

 config GENERIC_IRQ_PROBE
 	bool
 	default y

 # we have no ISA slots, but we do have ISA-style DMA.
 config ISA_DMA_API
 	bool
 	default y

 config GENERIC_PENDING_IRQ
 	bool
 	depends on GENERIC_HARDIRQS && SMP
 	default y

 menu "Power management options"

 source kernel/power/Kconfig

 source "drivers/acpi/Kconfig"

 source "arch/x86_64/kernel/cpufreq/Kconfig"

 endmenu

 menu "Bus options (PCI etc.)"

 config PCI
 	bool "PCI support"

 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
 config PCI_DIRECT
 	bool
 	depends on PCI
 	default y

 config PCI_MMCONFIG
 	bool "Support mmconfig PCI config space access"
 	depends on PCI && ACPI

 source "drivers/pci/pcie/Kconfig"

 source "drivers/pci/Kconfig"

 source "drivers/pcmcia/Kconfig"

 source "drivers/pci/hotplug/Kconfig"

 endmenu


 menu "Executable file formats / Emulations"

 source "fs/Kconfig.binfmt"

 config IA32_EMULATION
 	bool "IA32 Emulation"
 	help
 	  Include code to run 32-bit programs under a 64-bit kernel. You should likely
 	  turn this on, unless you're 100% sure that you don't have any 32-bit programs
 	  left.

 config IA32_AOUT
        tristate "IA32 a.out support"
        depends on IA32_EMULATION
        help
          Support old a.out binaries in the 32bit emulation.

 config COMPAT
 	bool
 	depends on IA32_EMULATION
 	default y

 config SYSVIPC_COMPAT
 	bool
 	depends on COMPAT && SYSVIPC
 	default y

 endmenu

 source "net/Kconfig"

 source drivers/Kconfig

 source "drivers/firmware/Kconfig"

 source fs/Kconfig

 menu "Instrumentation Support"
         depends on EXPERIMENTAL

 source "arch/x86_64/oprofile/Kconfig"

 config KPROBES
 	bool "Kprobes (EXPERIMENTAL)"
 	depends on EXPERIMENTAL && MODULES
 	help
 	  Kprobes allows you to trap at almost any kernel address and
 	  execute a callback function.  register_kprobe() establishes
 	  a probepoint and specifies the callback.  Kprobes is useful
 	  for kernel debugging, non-intrusive instrumentation and testing.
 	  If in doubt, say "N".
 endmenu

 source "arch/x86_64/Kconfig.debug"

 source "security/Kconfig"

 source "crypto/Kconfig"

 source "lib/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 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 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"
	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"
	---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 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
	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 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"
	default y
	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 (EXPERIMENTAL)"
	depends on EXPERIMENTAL
	help
	kexec is a system call that implements the ability to shutdown your
	current kernel, and to start another kernel. It is like a reboot
	but it is independent of the system firmware. And like a reboot
	you can start any kernel with it, not just Linux.

	The name comes from the similarity to the exec system call.

	It is an ongoing process to be certain the hardware in a machine
	is properly shutdown, so do not be surprised if this code does not
	initially work for you. It may help to enable device hotplugging
	support. As of this writing the exact hardware interface is
	strongly in flux, so no good recommendation can be made.

	config CRASH_DUMP
	bool "kernel crash dumps (EXPERIMENTAL)"
	depends on EXPERIMENTAL
	help
	Generate crash dump after being started by kexec.

	config PHYSICAL_START
	hex "Physical address where the kernel is loaded" if (EMBEDDED \|\| CRASH_DUMP)
	default "0x1000000" if CRASH_DUMP
	default "0x200000"
	help
	This gives the physical address where the kernel is loaded. Normally
	for regular kernels this value is 0x200000 (2MB). But in the case
	of kexec on panic the fail safe kernel needs to run at a different
	address than the panic-ed kernel. This option is used to set the load
	address for kernels used to capture crash dump on being kexec'ed
	after panic. The default value for crash dump kernels is
	0x1000000 (16MB). This can also be set based on the "X" value as
	specified in the "crashkernel=YM@XM" command line boot parameter
	passed to the panic-ed kernel. Typically this parameter is set as
	crashkernel=64M@16M. Please take a look at
	Documentation/kdump/kdump.txt for more details about crash dumps.

	Don't change this unless you know what you are doing.

	config SECCOMP
	bool "Enable seccomp to safely compute untrusted bytecode"
	depends on PROC_FS
	default y
	help
	This kernel feature is useful for number crunching applications
	that may need to compute untrusted bytecode during their
	execution. By using pipes or other transports made available to
	the process as file descriptors supporting the read/write
	syscalls, it's possible to isolate those applications in
	their own address space using seccomp. Once seccomp is
	enabled via /proc/<pid>/seccomp, it cannot be disabled
	and the task is only allowed to execute a few safe syscalls
	defined by each seccomp mode.

	If unsure, say Y. Only embedded should say N here.

	source kernel/Kconfig.hz

	config REORDER
	bool "Function reordering"
	default n
	help
	This option enables the toolchain to reorder functions for a more
	optimal TLB usage. If you have pretty much any version of binutils,
	this can increase your kernel build time by roughly one minute.

	config K8_NB
	def_bool y
	depends on AGP_AMD64 \|\| IOMMU \|\| (PCI && NUMA)

	endmenu

	#
	# Use the generic interrupt handling code in kernel/irq/:
	#
	config GENERIC_HARDIRQS
	bool
	default y

	config GENERIC_IRQ_PROBE
	bool
	default y

	# we have no ISA slots, but we do have ISA-style DMA.
	config ISA_DMA_API
	bool
	default y

	config GENERIC_PENDING_IRQ
	bool
	depends on GENERIC_HARDIRQS && SMP
	default y

	menu "Power management options"

	source kernel/power/Kconfig

	source "drivers/acpi/Kconfig"

	source "arch/x86_64/kernel/cpufreq/Kconfig"

	endmenu

	menu "Bus options (PCI etc.)"

	config PCI
	bool "PCI support"

	# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
	config PCI_DIRECT
	bool
	depends on PCI
	default y

	config PCI_MMCONFIG
	bool "Support mmconfig PCI config space access"
	depends on PCI && ACPI

	source "drivers/pci/pcie/Kconfig"

	source "drivers/pci/Kconfig"

	source "drivers/pcmcia/Kconfig"

	source "drivers/pci/hotplug/Kconfig"

	endmenu


	menu "Executable file formats / Emulations"

	source "fs/Kconfig.binfmt"

	config IA32_EMULATION
	bool "IA32 Emulation"
	help
	Include code to run 32-bit programs under a 64-bit kernel. You should likely
	turn this on, unless you're 100% sure that you don't have any 32-bit programs
	left.

	config IA32_AOUT
	tristate "IA32 a.out support"
	depends on IA32_EMULATION
	help
	Support old a.out binaries in the 32bit emulation.

	config COMPAT
	bool
	depends on IA32_EMULATION
	default y

	config SYSVIPC_COMPAT
	bool
	depends on COMPAT && SYSVIPC
	default y

	endmenu

	source "net/Kconfig"

	source drivers/Kconfig

	source "drivers/firmware/Kconfig"

	source fs/Kconfig

	menu "Instrumentation Support"
	depends on EXPERIMENTAL

	source "arch/x86_64/oprofile/Kconfig"

	config KPROBES
	bool "Kprobes (EXPERIMENTAL)"
	depends on EXPERIMENTAL && MODULES
	help
	Kprobes allows you to trap at almost any kernel address and
	execute a callback function. register_kprobe() establishes
	a probepoint and specifies the callback. Kprobes is useful
	for kernel debugging, non-intrusive instrumentation and testing.
	If in doubt, say "N".
	endmenu

	source "arch/x86_64/Kconfig.debug"

	source "security/Kconfig"

	source "crypto/Kconfig"

	source "lib/Kconfig"