arch/x86/Kconfig.cpu - linux/kernel/git/dhowells/linux-fs - Git at Google


            
            # SPDX-License-Identifier: GPL-2.0

            
            # Put here option for CPU selection and depending optimization

            
            choice

            
            	prompt "x86-32 Processor family"

            
            	depends on X86_32

            
            	default M686

            
            	help

            
            	  This is the processor type of your CPU. This information is

            
            	  used for optimizing purposes. In order to compile a kernel

            
            	  that can run on all supported x86 CPU types (albeit not

            
            	  optimally fast), you can specify "586" here.


            	  Note that the 386 and 486 is no longer supported, this includes

            
            	  AMD/Cyrix/Intel 386DX/DXL/SL/SLC/SX, Cyrix/TI 486DLC/DLC2,

            
            	  UMC 486SX-S and the NexGen Nx586, AMD ELAN and all 486 based

            
            	  CPUs.


            	  The kernel will not necessarily run on earlier architectures than

            
            	  the one you have chosen, e.g. a Pentium optimized kernel will run on

            
            	  a PPro, but not necessarily on a i486.


            	  Here are the settings recommended for greatest speed:

            
            	  - "586" for generic Pentium CPUs lacking the TSC

            
            	    (time stamp counter) register.

            
            	  - "Pentium-Classic" for the Intel Pentium.

            
            	  - "Pentium-MMX" for the Intel Pentium MMX.

            
            	  - "Pentium-Pro" for the Intel Pentium Pro.

            
            	  - "Pentium-II" for the Intel Pentium II or pre-Coppermine Celeron.

            
            	  - "Pentium-III" for the Intel Pentium III or Coppermine Celeron.

            
            	  - "Pentium-4" for the Intel Pentium 4 or P4-based Celeron.

            
            	  - "K6" for the AMD K6, K6-II and K6-III (aka K6-3D).

            
            	  - "Athlon" for the AMD K7 family (Athlon/Duron/Thunderbird).

            
            	  - "Crusoe" for the Transmeta Crusoe series.

            
            	  - "Efficeon" for the Transmeta Efficeon series.

            
            	  - "AMD Elan" for the 32-bit AMD Elan embedded CPU.

            
            	  - "GeodeGX1" for Geode GX1 (Cyrix MediaGX).

            
            	  - "Geode GX/LX" For AMD Geode GX and LX processors.

            
            	  - "CyrixIII/VIA C3" for VIA Cyrix III or VIA C3.

            
            	  - "VIA C3-2" for VIA C3-2 "Nehemiah" (model 9 and above).

            
            	  - "VIA C7" for VIA C7.

            
            	  - "Intel Atom" for the Atom-microarchitecture CPUs.


            	  See each option's help text for additional details. If you don't know

            
            	  what to do, choose "Pentium-Pro".


            config M586TSC

            
            	bool "Pentium-Classic"

            
            	depends on X86_32

            
            	help

            
            	  Select this for a Pentium Classic processor with the RDTSC (Read

            
            	  Time Stamp Counter) instruction for benchmarking.


            config M586MMX

            
            	bool "Pentium-MMX"

            
            	depends on X86_32

            
            	help

            
            	  Select this for a Pentium with the MMX graphics/multimedia

            
            	  extended instructions.


            config M686

            
            	bool "Pentium-Pro"

            
            	depends on X86_32

            
            	help

            
            	  Select this for Intel Pentium Pro chips.  This enables the use of

            
            	  Pentium Pro extended instructions, and disables the init-time guard

            
            	  against the f00f bug found in earlier Pentiums.


            config MPENTIUMII

            
            	bool "Pentium-II/Celeron(pre-Coppermine)"

            
            	depends on X86_32

            
            	help

            
            	  Select this for Intel chips based on the Pentium-II and

            
            	  pre-Coppermine Celeron core.  This option enables an unaligned

            
            	  copy optimization, compiles the kernel with optimization flags

            
            	  tailored for the chip, and applies any applicable Pentium Pro

            
            	  optimizations.


            config MPENTIUMIII

            
            	bool "Pentium-III/Celeron(Coppermine)/Pentium-III Xeon"

            
            	depends on X86_32

            
            	help

            
            	  Select this for Intel chips based on the Pentium-III and

            
            	  Celeron-Coppermine core.  This option enables use of some

            
            	  extended prefetch instructions in addition to the Pentium II

            
            	  extensions.


            config MPENTIUMM

            
            	bool "Pentium M/Pentium Dual Core/Core Solo/Core Duo"

            
            	depends on X86_32

            
            	help

            
            	  Select this for Intel Pentium M (not Pentium-4 M)

            
            	  "Merom" Core Solo/Duo notebook chips


            config MPENTIUM4

            
            	bool "Pentium-4/Celeron(P4-based)/Pentium-4 M/older Xeon"

            
            	depends on X86_32

            
            	help

            
            	  Select this for Intel Pentium 4 chips.  This includes the

            
            	  Pentium 4, Pentium D, P4-based Celeron and Xeon, and

            
            	  Pentium-4 M (not Pentium M) chips.  This option enables compile

            
            	  flags optimized for the chip, uses the correct cache line size, and

            
            	  applies any applicable optimizations.


            	  CPUIDs: F[0-6][1-A] (in /proc/cpuinfo show = cpu family : 15 )


            	  Select this for:

            
            	    Pentiums (Pentium 4, Pentium D, Celeron, Celeron D) corename:

            
            		-Willamette

            
            		-Northwood

            
            		-Mobile Pentium 4

            
            		-Mobile Pentium 4 M

            
            		-Extreme Edition (Gallatin)

            
            	    Xeons (Intel Xeon, Xeon MP, Xeon LV, Xeon MV) corename:

            
            		-Foster

            
            		-Prestonia

            
            		-Gallatin


            config MK6

            
            	bool "K6/K6-II/K6-III"

            
            	depends on X86_32

            
            	help

            
            	  Select this for an AMD K6-family processor.  Enables use of

            
            	  some extended instructions, and passes appropriate optimization

            
            	  flags to GCC.


            config MK7

            
            	bool "Athlon/Duron/K7"

            
            	depends on X86_32

            
            	help

            
            	  Select this for an AMD Athlon K7-family processor.  Enables use of

            
            	  some extended instructions, and passes appropriate optimization

            
            	  flags to GCC.


            config MCRUSOE

            
            	bool "Crusoe"

            
            	depends on X86_32

            
            	help

            
            	  Select this for a Transmeta Crusoe processor.  Treats the processor

            
            	  like a 586 with TSC, and sets some GCC optimization flags (like a

            
            	  Pentium Pro with no alignment requirements).


            config MEFFICEON

            
            	bool "Efficeon"

            
            	depends on X86_32

            
            	help

            
            	  Select this for a Transmeta Efficeon processor.


            config MGEODEGX1

            
            	bool "GeodeGX1"

            
            	depends on X86_32

            
            	help

            
            	  Select this for a Geode GX1 (Cyrix MediaGX) chip.


            config MGEODE_LX

            
            	bool "Geode GX/LX"

            
            	depends on X86_32

            
            	help

            
            	  Select this for AMD Geode GX and LX processors.


            config MCYRIXIII

            
            	bool "CyrixIII/VIA-C3"

            
            	depends on X86_32

            
            	help

            
            	  Select this for a Cyrix III or C3 chip.  Presently Linux and GCC

            
            	  treat this chip as a generic 586. Whilst the CPU is 686 class,

            
            	  it lacks the cmov extension which gcc assumes is present when

            
            	  generating 686 code.

            
            	  Note that Nehemiah (Model 9) and above will not boot with this

            
            	  kernel due to them lacking the 3DNow! instructions used in earlier

            
            	  incarnations of the CPU.


            config MVIAC3_2

            
            	bool "VIA C3-2 (Nehemiah)"

            
            	depends on X86_32

            
            	help

            
            	  Select this for a VIA C3 "Nehemiah". Selecting this enables usage

            
            	  of SSE and tells gcc to treat the CPU as a 686.

            
            	  Note, this kernel will not boot on older (pre model 9) C3s.


            config MVIAC7

            
            	bool "VIA C7"

            
            	depends on X86_32

            
            	help

            
            	  Select this for a VIA C7.  Selecting this uses the correct cache

            
            	  shift and tells gcc to treat the CPU as a 686.


            config MATOM

            
            	bool "Intel Atom"

            
            	help

            
            	  Select this for the Intel Atom platform. Intel Atom CPUs have an

            
            	  in-order pipelining architecture and thus can benefit from

            
            	  accordingly optimized code. Use a recent GCC with specific Atom

            
            	  support in order to fully benefit from selecting this option.


            endchoice


            config CC_HAS_MARCH_NATIVE

            
            	# This flag might not be available in cross-compilers:

            
            	def_bool $(cc-option, -march=native)

            
            	# LLVM 18 has an easily triggered internal compiler error in core

            
            	# networking code with '-march=native' on certain systems:

            
            	# https://github.com/llvm/llvm-project/issues/72026

            
            	# LLVM 19 introduces an optimization that resolves some high stack

            
            	# usage warnings that only appear wth '-march=native'.

            
            	depends on CC_IS_GCC || CLANG_VERSION >= 190100


            config RUSTC_HAS_APXF

            
            	# The kernel isn't ready for in-kernel APX instructions. Without

            
            	# explicit frontend gating of APX, the backend may emit those

            
            	# instructions in native builds.

            
            	#

            
            	# Rust 1.88 added the `apxf` feature option, but versions before 1.93

            
            	# emit an `apxf` target attribute that only LLVM 23+ can interpret.

            
            	def_bool (RUSTC_VERSION >= 108800 && RUSTC_LLVM_MAJOR_VERSION >= 23) || \

            
            		 RUSTC_VERSION >= 109300


            config X86_NATIVE_CPU

            
            	bool "Build and optimize for local/native CPU"

            
            	depends on X86_64

            
            	depends on CC_HAS_MARCH_NATIVE

            
            	depends on !RUST || RUSTC_HAS_APXF

            
            	help

            
            	  Optimize for the current CPU used to compile the kernel.

            
            	  Use this option if you intend to build the kernel for your

            
            	  local machine.


            	  Note that such a kernel might not work optimally on a

            
            	  different x86 machine.


            	  If unsure, say N.


            config X86_GENERIC

            
            	bool "Generic x86 support"

            
            	depends on X86_32

            
            	help

            
            	  Instead of just including optimizations for the selected

            
            	  x86 variant (e.g. PII, Crusoe or Athlon), include some more

            
            	  generic optimizations as well. This will make the kernel

            
            	  perform better on x86 CPUs other than that selected.


            	  This is really intended for distributors who need more

            
            	  generic optimizations.


            #

            
            # Define implied options from the CPU selection here

            
            config X86_INTERNODE_CACHE_SHIFT

            
            	int

            
            	default "12" if X86_VSMP

            
            	default X86_L1_CACHE_SHIFT


            config X86_L1_CACHE_SHIFT

            
            	int

            
            	default "7" if MPENTIUM4

            
            	default "6" if MK7 || MPENTIUMM || MATOM || MVIAC7 || X86_GENERIC || X86_64

            
            	default "4" if MGEODEGX1

            
            	default "5" if MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MVIAC3_2 || MGEODE_LX


            config X86_F00F_BUG

            
            	def_bool y

            
            	depends on M586MMX || M586TSC || M586


            config X86_ALIGNMENT_16

            
            	def_bool y

            
            	depends on MCYRIXIII || MK6 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODEGX1


            config X86_INTEL_USERCOPY

            
            	def_bool y

            
            	depends on MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M586MMX || X86_GENERIC || MK7 || MEFFICEON


            config X86_USE_PPRO_CHECKSUM

            
            	def_bool y

            
            	depends on MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MEFFICEON || MGEODE_LX || MATOM


            config X86_TSC

            
            	def_bool y


            config X86_HAVE_PAE

            
            	def_bool y

            
            	depends on MCRUSOE || MEFFICEON || MCYRIXIII || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC7 || MATOM || X86_64


            config X86_CX8

            
            	def_bool y


            # this should be set for all -march=.. options where the compiler

            
            # generates cmov.

            
            config X86_CMOV

            
            	def_bool y

            
            	depends on (MK7 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || MATOM || MGEODE_LX || X86_64)


            config X86_MINIMUM_CPU_FAMILY

            
            	int

            
            	default "64" if X86_64

            
            	default "6" if X86_32 && (MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MEFFICEON || MATOM || MK7)

            
            	default "5"


            config X86_DEBUGCTLMSR

            
            	def_bool y

            
            	depends on !(MK6 || MCYRIXIII || M586MMX || M586TSC || M586) && !UML


            config IA32_FEAT_CTL

            
            	def_bool y

            
            	depends on CPU_SUP_INTEL || CPU_SUP_CENTAUR || CPU_SUP_ZHAOXIN


            config X86_VMX_FEATURE_NAMES

            
            	def_bool y

            
            	depends on IA32_FEAT_CTL


            menuconfig PROCESSOR_SELECT

            
            	bool "Supported processor vendors" if EXPERT

            
            	help

            
            	  This lets you choose what x86 vendor support code your kernel

            
            	  will include.


            config CPU_SUP_INTEL

            
            	default y

            
            	bool "Support Intel processors" if PROCESSOR_SELECT

            
            	help

            
            	  This enables detection, tunings and quirks for Intel processors


            	  You need this enabled if you want your kernel to run on an

            
            	  Intel CPU. Disabling this option on other types of CPUs

            
            	  makes the kernel a tiny bit smaller. Disabling it on an Intel

            
            	  CPU might render the kernel unbootable.


            	  If unsure, say N.


            config CPU_SUP_CYRIX_32

            
            	default y

            
            	bool "Support Cyrix processors" if PROCESSOR_SELECT

            
            	depends on M586 || M586TSC || M586MMX || (EXPERT && !64BIT)

            
            	help

            
            	  This enables detection, tunings and quirks for Cyrix processors


            	  You need this enabled if you want your kernel to run on a

            
            	  Cyrix CPU. Disabling this option on other types of CPUs

            
            	  makes the kernel a tiny bit smaller. Disabling it on a Cyrix

            
            	  CPU might render the kernel unbootable.


            	  If unsure, say N.


            config CPU_SUP_AMD

            
            	default y

            
            	bool "Support AMD processors" if PROCESSOR_SELECT

            
            	help

            
            	  This enables detection, tunings and quirks for AMD processors


            	  You need this enabled if you want your kernel to run on an

            
            	  AMD CPU. Disabling this option on other types of CPUs

            
            	  makes the kernel a tiny bit smaller. Disabling it on an AMD

            
            	  CPU might render the kernel unbootable.


            	  If unsure, say N.


            config CPU_SUP_HYGON

            
            	default y

            
            	bool "Support Hygon processors" if PROCESSOR_SELECT

            
            	select CPU_SUP_AMD

            
            	help

            
            	  This enables detection, tunings and quirks for Hygon processors


            	  You need this enabled if you want your kernel to run on an

            
            	  Hygon CPU. Disabling this option on other types of CPUs

            
            	  makes the kernel a tiny bit smaller. Disabling it on an Hygon

            
            	  CPU might render the kernel unbootable.


            	  If unsure, say N.


            config CPU_SUP_CENTAUR

            
            	default y

            
            	bool "Support Centaur processors" if PROCESSOR_SELECT

            
            	help

            
            	  This enables detection, tunings and quirks for Centaur processors


            	  You need this enabled if you want your kernel to run on a

            
            	  Centaur CPU. Disabling this option on other types of CPUs

            
            	  makes the kernel a tiny bit smaller. Disabling it on a Centaur

            
            	  CPU might render the kernel unbootable.


            	  If unsure, say N.


            config CPU_SUP_TRANSMETA_32

            
            	default y

            
            	bool "Support Transmeta processors" if PROCESSOR_SELECT

            
            	depends on !64BIT

            
            	help

            
            	  This enables detection, tunings and quirks for Transmeta processors


            	  You need this enabled if you want your kernel to run on a

            
            	  Transmeta CPU. Disabling this option on other types of CPUs

            
            	  makes the kernel a tiny bit smaller. Disabling it on a Transmeta

            
            	  CPU might render the kernel unbootable.


            	  If unsure, say N.


            config CPU_SUP_ZHAOXIN

            
            	default y

            
            	bool "Support Zhaoxin processors" if PROCESSOR_SELECT

            
            	help

            
            	  This enables detection, tunings and quirks for Zhaoxin processors


            	  You need this enabled if you want your kernel to run on a

            
            	  Zhaoxin CPU. Disabling this option on other types of CPUs

            
            	  makes the kernel a tiny bit smaller. Disabling it on a Zhaoxin

            
            	  CPU might render the kernel unbootable.


            	  If unsure, say N.


            config CPU_SUP_VORTEX_32

            
            	default y

            
            	bool "Support Vortex processors" if PROCESSOR_SELECT

            
            	depends on X86_32

            
            	help

            
            	  This enables detection, tunings and quirks for Vortex processors


            	  You need this enabled if you want your kernel to run on a

            
            	  Vortex CPU. Disabling this option on other types of CPUs

            
            	  makes the kernel a tiny bit smaller.


            	  If unsure, say N.


            config BROADCAST_TLB_FLUSH

            
            	def_bool y

            
            	depends on CPU_SUP_AMD && 64BIT
	# SPDX-License-Identifier: GPL-2.0
	# Put here option for CPU selection and depending optimization
	choice
	prompt "x86-32 Processor family"
	depends on X86_32
	default M686
	help
	This is the processor type of your CPU. This information is
	used for optimizing purposes. In order to compile a kernel
	that can run on all supported x86 CPU types (albeit not
	optimally fast), you can specify "586" here.

	Note that the 386 and 486 is no longer supported, this includes
	AMD/Cyrix/Intel 386DX/DXL/SL/SLC/SX, Cyrix/TI 486DLC/DLC2,
	UMC 486SX-S and the NexGen Nx586, AMD ELAN and all 486 based
	CPUs.

	The kernel will not necessarily run on earlier architectures than
	the one you have chosen, e.g. a Pentium optimized kernel will run on
	a PPro, but not necessarily on a i486.

	Here are the settings recommended for greatest speed:
	- "586" for generic Pentium CPUs lacking the TSC
	(time stamp counter) register.
	- "Pentium-Classic" for the Intel Pentium.
	- "Pentium-MMX" for the Intel Pentium MMX.
	- "Pentium-Pro" for the Intel Pentium Pro.
	- "Pentium-II" for the Intel Pentium II or pre-Coppermine Celeron.
	- "Pentium-III" for the Intel Pentium III or Coppermine Celeron.
	- "Pentium-4" for the Intel Pentium 4 or P4-based Celeron.
	- "K6" for the AMD K6, K6-II and K6-III (aka K6-3D).
	- "Athlon" for the AMD K7 family (Athlon/Duron/Thunderbird).
	- "Crusoe" for the Transmeta Crusoe series.
	- "Efficeon" for the Transmeta Efficeon series.
	- "AMD Elan" for the 32-bit AMD Elan embedded CPU.
	- "GeodeGX1" for Geode GX1 (Cyrix MediaGX).
	- "Geode GX/LX" For AMD Geode GX and LX processors.
	- "CyrixIII/VIA C3" for VIA Cyrix III or VIA C3.
	- "VIA C3-2" for VIA C3-2 "Nehemiah" (model 9 and above).
	- "VIA C7" for VIA C7.
	- "Intel Atom" for the Atom-microarchitecture CPUs.

	See each option's help text for additional details. If you don't know
	what to do, choose "Pentium-Pro".

	config M586TSC
	bool "Pentium-Classic"
	depends on X86_32
	help
	Select this for a Pentium Classic processor with the RDTSC (Read
	Time Stamp Counter) instruction for benchmarking.

	config M586MMX
	bool "Pentium-MMX"
	depends on X86_32
	help
	Select this for a Pentium with the MMX graphics/multimedia
	extended instructions.

	config M686
	bool "Pentium-Pro"
	depends on X86_32
	help
	Select this for Intel Pentium Pro chips. This enables the use of
	Pentium Pro extended instructions, and disables the init-time guard
	against the f00f bug found in earlier Pentiums.

	config MPENTIUMII
	bool "Pentium-II/Celeron(pre-Coppermine)"
	depends on X86_32
	help
	Select this for Intel chips based on the Pentium-II and
	pre-Coppermine Celeron core. This option enables an unaligned
	copy optimization, compiles the kernel with optimization flags
	tailored for the chip, and applies any applicable Pentium Pro
	optimizations.

	config MPENTIUMIII
	bool "Pentium-III/Celeron(Coppermine)/Pentium-III Xeon"
	depends on X86_32
	help
	Select this for Intel chips based on the Pentium-III and
	Celeron-Coppermine core. This option enables use of some
	extended prefetch instructions in addition to the Pentium II
	extensions.

	config MPENTIUMM
	bool "Pentium M/Pentium Dual Core/Core Solo/Core Duo"
	depends on X86_32
	help
	Select this for Intel Pentium M (not Pentium-4 M)
	"Merom" Core Solo/Duo notebook chips

	config MPENTIUM4
	bool "Pentium-4/Celeron(P4-based)/Pentium-4 M/older Xeon"
	depends on X86_32
	help
	Select this for Intel Pentium 4 chips. This includes the
	Pentium 4, Pentium D, P4-based Celeron and Xeon, and
	Pentium-4 M (not Pentium M) chips. This option enables compile
	flags optimized for the chip, uses the correct cache line size, and
	applies any applicable optimizations.

	CPUIDs: F[0-6][1-A] (in /proc/cpuinfo show = cpu family : 15 )

	Select this for:
	Pentiums (Pentium 4, Pentium D, Celeron, Celeron D) corename:
	-Willamette
	-Northwood
	-Mobile Pentium 4
	-Mobile Pentium 4 M
	-Extreme Edition (Gallatin)
	Xeons (Intel Xeon, Xeon MP, Xeon LV, Xeon MV) corename:
	-Foster
	-Prestonia
	-Gallatin

	config MK6
	bool "K6/K6-II/K6-III"
	depends on X86_32
	help
	Select this for an AMD K6-family processor. Enables use of
	some extended instructions, and passes appropriate optimization
	flags to GCC.

	config MK7
	bool "Athlon/Duron/K7"
	depends on X86_32
	help
	Select this for an AMD Athlon K7-family processor. Enables use of
	some extended instructions, and passes appropriate optimization
	flags to GCC.

	config MCRUSOE
	bool "Crusoe"
	depends on X86_32
	help
	Select this for a Transmeta Crusoe processor. Treats the processor
	like a 586 with TSC, and sets some GCC optimization flags (like a
	Pentium Pro with no alignment requirements).

	config MEFFICEON
	bool "Efficeon"
	depends on X86_32
	help
	Select this for a Transmeta Efficeon processor.

	config MGEODEGX1
	bool "GeodeGX1"
	depends on X86_32
	help
	Select this for a Geode GX1 (Cyrix MediaGX) chip.

	config MGEODE_LX
	bool "Geode GX/LX"
	depends on X86_32
	help
	Select this for AMD Geode GX and LX processors.

	config MCYRIXIII
	bool "CyrixIII/VIA-C3"
	depends on X86_32
	help
	Select this for a Cyrix III or C3 chip. Presently Linux and GCC
	treat this chip as a generic 586. Whilst the CPU is 686 class,
	it lacks the cmov extension which gcc assumes is present when
	generating 686 code.
	Note that Nehemiah (Model 9) and above will not boot with this
	kernel due to them lacking the 3DNow! instructions used in earlier
	incarnations of the CPU.

	config MVIAC3_2
	bool "VIA C3-2 (Nehemiah)"
	depends on X86_32
	help
	Select this for a VIA C3 "Nehemiah". Selecting this enables usage
	of SSE and tells gcc to treat the CPU as a 686.
	Note, this kernel will not boot on older (pre model 9) C3s.

	config MVIAC7
	bool "VIA C7"
	depends on X86_32
	help
	Select this for a VIA C7. Selecting this uses the correct cache
	shift and tells gcc to treat the CPU as a 686.

	config MATOM
	bool "Intel Atom"
	help
	Select this for the Intel Atom platform. Intel Atom CPUs have an
	in-order pipelining architecture and thus can benefit from
	accordingly optimized code. Use a recent GCC with specific Atom
	support in order to fully benefit from selecting this option.

	endchoice

	config CC_HAS_MARCH_NATIVE
	# This flag might not be available in cross-compilers:
	def_bool $(cc-option, -march=native)
	# LLVM 18 has an easily triggered internal compiler error in core
	# networking code with '-march=native' on certain systems:
	# https://github.com/llvm/llvm-project/issues/72026
	# LLVM 19 introduces an optimization that resolves some high stack
	# usage warnings that only appear wth '-march=native'.
	depends on CC_IS_GCC \|\| CLANG_VERSION >= 190100

	config RUSTC_HAS_APXF
	# The kernel isn't ready for in-kernel APX instructions. Without
	# explicit frontend gating of APX, the backend may emit those
	# instructions in native builds.
	#
	# Rust 1.88 added the `apxf` feature option, but versions before 1.93
	# emit an `apxf` target attribute that only LLVM 23+ can interpret.
	def_bool (RUSTC_VERSION >= 108800 && RUSTC_LLVM_MAJOR_VERSION >= 23) \|\| \
	RUSTC_VERSION >= 109300

	config X86_NATIVE_CPU
	bool "Build and optimize for local/native CPU"
	depends on X86_64
	depends on CC_HAS_MARCH_NATIVE
	depends on !RUST \|\| RUSTC_HAS_APXF
	help
	Optimize for the current CPU used to compile the kernel.
	Use this option if you intend to build the kernel for your
	local machine.

	Note that such a kernel might not work optimally on a
	different x86 machine.

	If unsure, say N.

	config X86_GENERIC
	bool "Generic x86 support"
	depends on X86_32
	help
	Instead of just including optimizations for the selected
	x86 variant (e.g. PII, Crusoe or Athlon), include some more
	generic optimizations as well. This will make the kernel
	perform better on x86 CPUs other than that selected.

	This is really intended for distributors who need more
	generic optimizations.

	#
	# Define implied options from the CPU selection here
	config X86_INTERNODE_CACHE_SHIFT
	int
	default "12" if X86_VSMP
	default X86_L1_CACHE_SHIFT

	config X86_L1_CACHE_SHIFT
	int
	default "7" if MPENTIUM4
	default "6" if MK7 \|\| MPENTIUMM \|\| MATOM \|\| MVIAC7 \|\| X86_GENERIC \|\| X86_64
	default "4" if MGEODEGX1
	default "5" if MCRUSOE \|\| MEFFICEON \|\| MCYRIXIII \|\| MK6 \|\| MPENTIUMIII \|\| MPENTIUMII \|\| M686 \|\| M586MMX \|\| M586TSC \|\| MVIAC3_2 \|\| MGEODE_LX

	config X86_F00F_BUG
	def_bool y
	depends on M586MMX \|\| M586TSC \|\| M586

	config X86_ALIGNMENT_16
	def_bool y
	depends on MCYRIXIII \|\| MK6 \|\| M586MMX \|\| M586TSC \|\| M586 \|\| MVIAC3_2 \|\| MGEODEGX1

	config X86_INTEL_USERCOPY
	def_bool y
	depends on MPENTIUM4 \|\| MPENTIUMM \|\| MPENTIUMIII \|\| MPENTIUMII \|\| M586MMX \|\| X86_GENERIC \|\| MK7 \|\| MEFFICEON

	config X86_USE_PPRO_CHECKSUM
	def_bool y
	depends on MCYRIXIII \|\| MK7 \|\| MK6 \|\| MPENTIUM4 \|\| MPENTIUMM \|\| MPENTIUMIII \|\| MPENTIUMII \|\| M686 \|\| MVIAC3_2 \|\| MVIAC7 \|\| MEFFICEON \|\| MGEODE_LX \|\| MATOM

	config X86_TSC
	def_bool y

	config X86_HAVE_PAE
	def_bool y
	depends on MCRUSOE \|\| MEFFICEON \|\| MCYRIXIII \|\| MPENTIUM4 \|\| MPENTIUMM \|\| MPENTIUMIII \|\| MPENTIUMII \|\| M686 \|\| MVIAC7 \|\| MATOM \|\| X86_64

	config X86_CX8
	def_bool y

	# this should be set for all -march=.. options where the compiler
	# generates cmov.
	config X86_CMOV
	def_bool y
	depends on (MK7 \|\| MPENTIUM4 \|\| MPENTIUMM \|\| MPENTIUMIII \|\| MPENTIUMII \|\| M686 \|\| MVIAC3_2 \|\| MVIAC7 \|\| MCRUSOE \|\| MEFFICEON \|\| MATOM \|\| MGEODE_LX \|\| X86_64)

	config X86_MINIMUM_CPU_FAMILY
	int
	default "64" if X86_64
	default "6" if X86_32 && (MPENTIUM4 \|\| MPENTIUMM \|\| MPENTIUMIII \|\| MPENTIUMII \|\| M686 \|\| MVIAC3_2 \|\| MVIAC7 \|\| MEFFICEON \|\| MATOM \|\| MK7)
	default "5"

	config X86_DEBUGCTLMSR
	def_bool y
	depends on !(MK6 \|\| MCYRIXIII \|\| M586MMX \|\| M586TSC \|\| M586) && !UML

	config IA32_FEAT_CTL
	def_bool y
	depends on CPU_SUP_INTEL \|\| CPU_SUP_CENTAUR \|\| CPU_SUP_ZHAOXIN

	config X86_VMX_FEATURE_NAMES
	def_bool y
	depends on IA32_FEAT_CTL

	menuconfig PROCESSOR_SELECT
	bool "Supported processor vendors" if EXPERT
	help
	This lets you choose what x86 vendor support code your kernel
	will include.

	config CPU_SUP_INTEL
	default y
	bool "Support Intel processors" if PROCESSOR_SELECT
	help
	This enables detection, tunings and quirks for Intel processors

	You need this enabled if you want your kernel to run on an
	Intel CPU. Disabling this option on other types of CPUs
	makes the kernel a tiny bit smaller. Disabling it on an Intel
	CPU might render the kernel unbootable.

	If unsure, say N.

	config CPU_SUP_CYRIX_32
	default y
	bool "Support Cyrix processors" if PROCESSOR_SELECT
	depends on M586 \|\| M586TSC \|\| M586MMX \|\| (EXPERT && !64BIT)
	help
	This enables detection, tunings and quirks for Cyrix processors

	You need this enabled if you want your kernel to run on a
	Cyrix CPU. Disabling this option on other types of CPUs
	makes the kernel a tiny bit smaller. Disabling it on a Cyrix
	CPU might render the kernel unbootable.

	If unsure, say N.

	config CPU_SUP_AMD
	default y
	bool "Support AMD processors" if PROCESSOR_SELECT
	help
	This enables detection, tunings and quirks for AMD processors

	You need this enabled if you want your kernel to run on an
	AMD CPU. Disabling this option on other types of CPUs
	makes the kernel a tiny bit smaller. Disabling it on an AMD
	CPU might render the kernel unbootable.

	If unsure, say N.

	config CPU_SUP_HYGON
	default y
	bool "Support Hygon processors" if PROCESSOR_SELECT
	select CPU_SUP_AMD
	help
	This enables detection, tunings and quirks for Hygon processors

	You need this enabled if you want your kernel to run on an
	Hygon CPU. Disabling this option on other types of CPUs
	makes the kernel a tiny bit smaller. Disabling it on an Hygon
	CPU might render the kernel unbootable.

	If unsure, say N.

	config CPU_SUP_CENTAUR
	default y
	bool "Support Centaur processors" if PROCESSOR_SELECT
	help
	This enables detection, tunings and quirks for Centaur processors

	You need this enabled if you want your kernel to run on a
	Centaur CPU. Disabling this option on other types of CPUs
	makes the kernel a tiny bit smaller. Disabling it on a Centaur
	CPU might render the kernel unbootable.

	If unsure, say N.

	config CPU_SUP_TRANSMETA_32
	default y
	bool "Support Transmeta processors" if PROCESSOR_SELECT
	depends on !64BIT
	help
	This enables detection, tunings and quirks for Transmeta processors

	You need this enabled if you want your kernel to run on a
	Transmeta CPU. Disabling this option on other types of CPUs
	makes the kernel a tiny bit smaller. Disabling it on a Transmeta
	CPU might render the kernel unbootable.

	If unsure, say N.

	config CPU_SUP_ZHAOXIN
	default y
	bool "Support Zhaoxin processors" if PROCESSOR_SELECT
	help
	This enables detection, tunings and quirks for Zhaoxin processors

	You need this enabled if you want your kernel to run on a
	Zhaoxin CPU. Disabling this option on other types of CPUs
	makes the kernel a tiny bit smaller. Disabling it on a Zhaoxin
	CPU might render the kernel unbootable.

	If unsure, say N.

	config CPU_SUP_VORTEX_32
	default y
	bool "Support Vortex processors" if PROCESSOR_SELECT
	depends on X86_32
	help
	This enables detection, tunings and quirks for Vortex processors

	You need this enabled if you want your kernel to run on a
	Vortex CPU. Disabling this option on other types of CPUs
	makes the kernel a tiny bit smaller.

	If unsure, say N.

	config BROADCAST_TLB_FLUSH
	def_bool y
	depends on CPU_SUP_AMD && 64BIT