# Put here option for CPU selection and depending optimization
if !X86_ELAN
choice
prompt "Processor family"
default M686 if X86_32
default GENERIC_CPU if X86_64
config M386
bool "386"
depends on X86_32 && !UML
---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 x86 CPU types (albeit not optimally fast), you can specify
"386" here.
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:
- "386" for the AMD/Cyrix/Intel 386DX/DXL/SL/SLC/SX, Cyrix/TI
486DLC/DLC2, and UMC 486SX-S. Only "386" kernels will run on a 386
class machine.
- "486" for the AMD/Cyrix/IBM/Intel 486DX/DX2/DX4 or
SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or U5S.
- "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.
- "Winchip-C6" for original IDT Winchip.
- "Winchip-2" for IDT Winchip 2.
- "Winchip-2A" for IDT Winchips with 3dNow! capabilities.
- "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.
If you don't know what to do, choose "386".
config M486
bool "486"
depends on X86_32
help
Select this for a 486 series processor, either Intel or one of the
compatible processors from AMD, Cyrix, IBM, or Intel. Includes DX,
DX2, and DX4 variants; also SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or
U5S.
config M586
bool "586/K5/5x86/6x86/6x86MX"
depends on X86_32
help
Select this for an 586 or 686 series processor such as the AMD K5,
the Cyrix 5x86, 6x86 and 6x86MX. This choice does not
assume the RDTSC (Read Time Stamp Counter) instruction.
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"
depends on X86_32
help
Select this for Intel Pentium M (not Pentium-4 M)
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)
-Prescott
-Prescott 2M
-Cedar Mill
-Presler
-Smithfiled
Xeons (Intel Xeon, Xeon MP, Xeon LV, Xeon MV) corename:
-Foster
-Prestonia
-Gallatin
-Nocona
-Irwindale
-Cranford
-Potomac
-Paxville
-Dempsey
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 MK8
bool "Opteron/Athlon64/Hammer/K8"
help
Select this for an AMD Opteron or Athlon64 Hammer-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 MWINCHIPC6
bool "Winchip-C6"
depends on X86_32
help
Select this for an IDT Winchip C6 chip. Linux and GCC
treat this chip as a 586TSC with some extended instructions
and alignment requirements.
config MWINCHIP2
bool "Winchip-2"
depends on X86_32
help
Select this for an IDT Winchip-2. Linux and GCC
treat this chip as a 586TSC with some extended instructions
and alignment requirements.
config MWINCHIP3D
bool "Winchip-2A/Winchip-3"
depends on X86_32
help
Select this for an IDT Winchip-2A or 3. Linux and GCC
treat this chip as a 586TSC with some extended instructions
and alignment requirements. Also enable out of order memory
stores for this CPU, which can increase performance of some
operations.
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 MPSC
bool "Intel P4 / older Netburst based Xeon"
depends on X86_64
help
Optimize for Intel Pentium 4, Pentium D and older Nocona/Dempsey
Xeon CPUs with Intel 64bit which is compatible with x86-64.
Note that the latest Xeons (Xeon 51xx and 53xx) are not based on the
Netburst core and shouldn't use this option. You can distinguish them
using the cpu family field
in /proc/cpuinfo. Family 15 is an older Xeon, Family 6 a newer one.
config MCORE2
bool "Core 2/newer Xeon"
help
Select this for Intel Core 2 and newer Core 2 Xeons (Xeon 51xx and 53xx)
CPUs. You can distinguish newer from older Xeons by the CPU family
in /proc/cpuinfo. Newer ones have 6 and older ones 15 (not a typo)
config GENERIC_CPU
bool "Generic-x86-64"
depends on X86_64
help
Generic x86-64 CPU.
Run equally well on all x86-64 CPUs.
endchoice
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.
endif
config X86_CPU
def_bool y
select GENERIC_FIND_FIRST_BIT
select GENERIC_FIND_NEXT_BIT
#
# Define implied options from the CPU selection here
config X86_L1_CACHE_BYTES
int
default "128" if GENERIC_CPU || MPSC
default "64" if MK8 || MCORE2
depends on X86_64
config X86_INTERNODE_CACHE_BYTES
int
default "4096" if X86_VSMP
default X86_L1_CACHE_BYTES if !X86_VSMP
depends on X86_64
config X86_CMPXCHG
def_bool X86_64 || (X86_32 && !M386)
config X86_L1_CACHE_SHIFT
int
default "7" if MPENTIUM4 || X86_GENERIC || GENERIC_CPU || MPSC
default "4" if X86_ELAN || M486 || M386 || MGEODEGX1
default "5" if MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODE_LX
default "6" if MK7 || MK8 || MPENTIUMM || MCORE2 || MVIAC7
config X86_XADD
def_bool y
depends on X86_32 && !M386
config X86_PPRO_FENCE
bool "PentiumPro memory ordering errata workaround"
depends on M686 || M586MMX || M586TSC || M586 || M486 || M386 || MGEODEGX1
help
Old PentiumPro multiprocessor systems had errata that could cause memory
operations to violate the x86 ordering standard in rare cases. Enabling this
option will attempt to work around some (but not all) occurances of
this problem, at the cost of much heavier spinlock and memory barrier
operations.
If unsure, say n here. Even distro kernels should think twice before enabling
this: there are few systems, and an unlikely bug.
config X86_F00F_BUG
def_bool y
depends on M586MMX || M586TSC || M586 || M486 || M386
config X86_WP_WORKS_OK
def_bool y
depends on !M386
config X86_INVLPG
def_bool y
depends on X86_32 && !M386
config X86_BSWAP
def_bool y
depends on X86_32 && !M386
config X86_POPAD_OK
def_bool y
depends on X86_32 && !M386
config X86_ALIGNMENT_16
def_bool y
depends on MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCYRIXIII || X86_ELAN || MK6 || M586MMX || M586TSC || M586 || M486 || MVIAC3_2 || MGEODEGX1
config X86_INTEL_USERCOPY
def_bool y
depends on MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M586MMX || X86_GENERIC || MK8 || MK7 || MEFFICEON || MCORE2
config X86_USE_PPRO_CHECKSUM
def_bool y
depends on MWINCHIP3D || MWINCHIP2 || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2 || MEFFICEON || MGEODE_LX || MCORE2
config X86_USE_3DNOW
def_bool y
depends on (MCYRIXIII || MK7 || MGEODE_LX) && !UML
config X86_OOSTORE
def_bool y
depends on (MWINCHIP3D || MWINCHIP2 || MWINCHIPC6) && MTRR
#
# P6_NOPs are a relatively minor optimization that require a family >=
# 6 processor, except that it is broken on certain VIA chips.
# Furthermore, AMD chips prefer a totally different sequence of NOPs
# (which work on all CPUs). As a result, disallow these if we're
# compiling X86_GENERIC but not X86_64 (these NOPs do work on all
# x86-64 capable chips); the list of processors in the right-hand clause
# are the cores that benefit from this optimization.
#
config X86_P6_NOP
def_bool y
depends on (X86_64 || !X86_GENERIC) && (M686 || MPENTIUMII || MPENTIUMIII || MPENTIUMM || MCORE2 || MPENTIUM4 || MPSC)
config X86_TSC
def_bool y
depends on ((MWINCHIP3D || MWINCHIP2 || MCRUSOE || MEFFICEON || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MK8 || MVIAC3_2 || MVIAC7 || MGEODEGX1 || MGEODE_LX || MCORE2) && !X86_NUMAQ) || X86_64
config X86_CMPXCHG64
def_bool y
depends on X86_PAE || X86_64
# 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 || X86_64)
config X86_MINIMUM_CPU_FAMILY
int
default "64" if X86_64
default "6" if X86_32 && X86_P6_NOP
default "4" if X86_32 && (X86_XADD || X86_CMPXCHG || X86_BSWAP || X86_WP_WORKS_OK)
default "3"
config X86_DEBUGCTLMSR
def_bool y
depends on !(M586MMX || M586TSC || M586 || M486 || M386)
