1 # Put here option for CPU selection and depending optimization
3 prompt "Processor family"
5 default GENERIC_CPU if X86_64
7 This is the processor type of your CPU. This information is
8 used for optimizing purposes. In order to compile a kernel
9 that can run on all supported x86 CPU types (albeit not
10 optimally fast), you can specify "486" here.
12 Note that the 386 is no longer supported, this includes
13 AMD/Cyrix/Intel 386DX/DXL/SL/SLC/SX, Cyrix/TI 486DLC/DLC2,
14 UMC 486SX-S and the NexGen Nx586.
16 The kernel will not necessarily run on earlier architectures than
17 the one you have chosen, e.g. a Pentium optimized kernel will run on
18 a PPro, but not necessarily on a i486.
20 Here are the settings recommended for greatest speed:
21 - "486" for the AMD/Cyrix/IBM/Intel 486DX/DX2/DX4 or
22 SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or U5S.
23 - "586" for generic Pentium CPUs lacking the TSC
24 (time stamp counter) register.
25 - "Pentium-Classic" for the Intel Pentium.
26 - "Pentium-MMX" for the Intel Pentium MMX.
27 - "Pentium-Pro" for the Intel Pentium Pro.
28 - "Pentium-II" for the Intel Pentium II or pre-Coppermine Celeron.
29 - "Pentium-III" for the Intel Pentium III or Coppermine Celeron.
30 - "Pentium-4" for the Intel Pentium 4 or P4-based Celeron.
31 - "K6" for the AMD K6, K6-II and K6-III (aka K6-3D).
32 - "Athlon" for the AMD K7 family (Athlon/Duron/Thunderbird).
33 - "Opteron/Athlon64/Hammer/K8" for all K8 and newer AMD CPUs.
34 - "Crusoe" for the Transmeta Crusoe series.
35 - "Efficeon" for the Transmeta Efficeon series.
36 - "Winchip-C6" for original IDT Winchip.
37 - "Winchip-2" for IDT Winchips with 3dNow! capabilities.
38 - "AMD Elan" for the 32-bit AMD Elan embedded CPU.
39 - "GeodeGX1" for Geode GX1 (Cyrix MediaGX).
40 - "Geode GX/LX" For AMD Geode GX and LX processors.
41 - "CyrixIII/VIA C3" for VIA Cyrix III or VIA C3.
42 - "VIA C3-2" for VIA C3-2 "Nehemiah" (model 9 and above).
43 - "VIA C7" for VIA C7.
44 - "Intel P4" for the Pentium 4/Netburst microarchitecture.
45 - "Core 2/newer Xeon" for all core2 and newer Intel CPUs.
46 - "Intel Atom" for the Atom-microarchitecture CPUs.
47 - "Generic-x86-64" for a kernel which runs on any x86-64 CPU.
49 See each option's help text for additional details. If you don't know
50 what to do, choose "486".
56 Select this for an 486-class CPU such as AMD/Cyrix/IBM/Intel
57 486DX/DX2/DX4 or SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or U5S.
60 bool "586/K5/5x86/6x86/6x86MX"
63 Select this for an 586 or 686 series processor such as the AMD K5,
64 the Cyrix 5x86, 6x86 and 6x86MX. This choice does not
65 assume the RDTSC (Read Time Stamp Counter) instruction.
68 bool "Pentium-Classic"
71 Select this for a Pentium Classic processor with the RDTSC (Read
72 Time Stamp Counter) instruction for benchmarking.
78 Select this for a Pentium with the MMX graphics/multimedia
79 extended instructions.
85 Select this for Intel Pentium Pro chips. This enables the use of
86 Pentium Pro extended instructions, and disables the init-time guard
87 against the f00f bug found in earlier Pentiums.
90 bool "Pentium-II/Celeron(pre-Coppermine)"
93 Select this for Intel chips based on the Pentium-II and
94 pre-Coppermine Celeron core. This option enables an unaligned
95 copy optimization, compiles the kernel with optimization flags
96 tailored for the chip, and applies any applicable Pentium Pro
100 bool "Pentium-III/Celeron(Coppermine)/Pentium-III Xeon"
103 Select this for Intel chips based on the Pentium-III and
104 Celeron-Coppermine core. This option enables use of some
105 extended prefetch instructions in addition to the Pentium II
112 Select this for Intel Pentium M (not Pentium-4 M)
116 bool "Pentium-4/Celeron(P4-based)/Pentium-4 M/older Xeon"
119 Select this for Intel Pentium 4 chips. This includes the
120 Pentium 4, Pentium D, P4-based Celeron and Xeon, and
121 Pentium-4 M (not Pentium M) chips. This option enables compile
122 flags optimized for the chip, uses the correct cache line size, and
123 applies any applicable optimizations.
125 CPUIDs: F[0-6][1-A] (in /proc/cpuinfo show = cpu family : 15 )
128 Pentiums (Pentium 4, Pentium D, Celeron, Celeron D) corename:
133 -Extreme Edition (Gallatin)
139 Xeons (Intel Xeon, Xeon MP, Xeon LV, Xeon MV) corename:
152 bool "K6/K6-II/K6-III"
155 Select this for an AMD K6-family processor. Enables use of
156 some extended instructions, and passes appropriate optimization
160 bool "Athlon/Duron/K7"
163 Select this for an AMD Athlon K7-family processor. Enables use of
164 some extended instructions, and passes appropriate optimization
168 bool "Opteron/Athlon64/Hammer/K8"
170 Select this for an AMD Opteron or Athlon64 Hammer-family processor.
171 Enables use of some extended instructions, and passes appropriate
172 optimization flags to GCC.
178 Select this for a Transmeta Crusoe processor. Treats the processor
179 like a 586 with TSC, and sets some GCC optimization flags (like a
180 Pentium Pro with no alignment requirements).
186 Select this for a Transmeta Efficeon processor.
192 Select this for an IDT Winchip C6 chip. Linux and GCC
193 treat this chip as a 586TSC with some extended instructions
194 and alignment requirements.
197 bool "Winchip-2/Winchip-2A/Winchip-3"
200 Select this for an IDT Winchip-2, 2A or 3. Linux and GCC
201 treat this chip as a 586TSC with some extended instructions
202 and alignment requirements. Also enable out of order memory
203 stores for this CPU, which can increase performance of some
210 Select this for an AMD Elan processor.
212 Do not use this option for K6/Athlon/Opteron processors!
218 Select this for a Geode GX1 (Cyrix MediaGX) chip.
224 Select this for AMD Geode GX and LX processors.
227 bool "CyrixIII/VIA-C3"
230 Select this for a Cyrix III or C3 chip. Presently Linux and GCC
231 treat this chip as a generic 586. Whilst the CPU is 686 class,
232 it lacks the cmov extension which gcc assumes is present when
234 Note that Nehemiah (Model 9) and above will not boot with this
235 kernel due to them lacking the 3DNow! instructions used in earlier
236 incarnations of the CPU.
239 bool "VIA C3-2 (Nehemiah)"
242 Select this for a VIA C3 "Nehemiah". Selecting this enables usage
243 of SSE and tells gcc to treat the CPU as a 686.
244 Note, this kernel will not boot on older (pre model 9) C3s.
250 Select this for a VIA C7. Selecting this uses the correct cache
251 shift and tells gcc to treat the CPU as a 686.
254 bool "Intel P4 / older Netburst based Xeon"
257 Optimize for Intel Pentium 4, Pentium D and older Nocona/Dempsey
258 Xeon CPUs with Intel 64bit which is compatible with x86-64.
259 Note that the latest Xeons (Xeon 51xx and 53xx) are not based on the
260 Netburst core and shouldn't use this option. You can distinguish them
261 using the cpu family field
262 in /proc/cpuinfo. Family 15 is an older Xeon, Family 6 a newer one.
265 bool "Core 2/newer Xeon"
268 Select this for Intel Core 2 and newer Core 2 Xeons (Xeon 51xx and
269 53xx) CPUs. You can distinguish newer from older Xeons by the CPU
270 family in /proc/cpuinfo. Newer ones have 6 and older ones 15
277 Select this for the Intel Atom platform. Intel Atom CPUs have an
278 in-order pipelining architecture and thus can benefit from
279 accordingly optimized code. Use a recent GCC with specific Atom
280 support in order to fully benefit from selecting this option.
283 bool "Generic-x86-64"
287 Run equally well on all x86-64 CPUs.
292 bool "Generic x86 support"
295 Instead of just including optimizations for the selected
296 x86 variant (e.g. PII, Crusoe or Athlon), include some more
297 generic optimizations as well. This will make the kernel
298 perform better on x86 CPUs other than that selected.
300 This is really intended for distributors who need more
301 generic optimizations.
304 # Define implied options from the CPU selection here
305 config X86_INTERNODE_CACHE_SHIFT
307 default "12" if X86_VSMP
308 default X86_L1_CACHE_SHIFT
310 config X86_L1_CACHE_SHIFT
312 default "7" if MPENTIUM4 || MPSC
313 default "6" if MK7 || MK8 || MPENTIUMM || MCORE2 || MATOM || MVIAC7 || X86_GENERIC || GENERIC_CPU
314 default "4" if MELAN || M486 || MGEODEGX1
315 default "5" if MWINCHIP3D || MWINCHIPC6 || MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODE_LX
317 config X86_PPRO_FENCE
318 bool "PentiumPro memory ordering errata workaround"
319 depends on M686 || M586MMX || M586TSC || M586 || M486 || MGEODEGX1
321 Old PentiumPro multiprocessor systems had errata that could cause
322 memory operations to violate the x86 ordering standard in rare cases.
323 Enabling this option will attempt to work around some (but not all)
324 occurrences of this problem, at the cost of much heavier spinlock and
325 memory barrier operations.
327 If unsure, say n here. Even distro kernels should think twice before
328 enabling this: there are few systems, and an unlikely bug.
332 depends on M586MMX || M586TSC || M586 || M486
338 config X86_ALIGNMENT_16
340 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MELAN || MK6 || M586MMX || M586TSC || M586 || M486 || MVIAC3_2 || MGEODEGX1
342 config X86_INTEL_USERCOPY
344 depends on MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M586MMX || X86_GENERIC || MK8 || MK7 || MEFFICEON || MCORE2
346 config X86_USE_PPRO_CHECKSUM
348 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2 || MVIAC7 || MEFFICEON || MGEODE_LX || MCORE2 || MATOM
352 depends on (MCYRIXIII || MK7 || MGEODE_LX) && !UML
355 # P6_NOPs are a relatively minor optimization that require a family >=
356 # 6 processor, except that it is broken on certain VIA chips.
357 # Furthermore, AMD chips prefer a totally different sequence of NOPs
358 # (which work on all CPUs). In addition, it looks like Virtual PC
359 # does not understand them.
361 # As a result, disallow these if we're not compiling for X86_64 (these
362 # NOPs do work on all x86-64 capable chips); the list of processors in
363 # the right-hand clause are the cores that benefit from this optimization.
368 depends on (MCORE2 || MPENTIUM4 || MPSC)
372 depends on (MWINCHIP3D || MCRUSOE || MEFFICEON || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MK8 || MVIAC3_2 || MVIAC7 || MGEODEGX1 || MGEODE_LX || MCORE2 || MATOM) || X86_64
376 depends on X86_PAE || X86_64 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MATOM
378 # this should be set for all -march=.. options where the compiler
382 depends on (MK8 || MK7 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM || MGEODE_LX)
384 config X86_MINIMUM_CPU_FAMILY
386 default "64" if X86_64
387 default "6" if X86_32 && X86_P6_NOP
388 default "5" if X86_32 && X86_CMPXCHG64
391 config X86_DEBUGCTLMSR
393 depends on !(MK6 || MWINCHIPC6 || MWINCHIP3D || MCYRIXIII || M586MMX || M586TSC || M586 || M486) && !UML
395 menuconfig PROCESSOR_SELECT
396 bool "Supported processor vendors" if EXPERT
398 This lets you choose what x86 vendor support code your kernel
403 bool "Support Intel processors" if PROCESSOR_SELECT
405 This enables detection, tunings and quirks for Intel processors
407 You need this enabled if you want your kernel to run on an
408 Intel CPU. Disabling this option on other types of CPUs
409 makes the kernel a tiny bit smaller. Disabling it on an Intel
410 CPU might render the kernel unbootable.
414 config CPU_SUP_CYRIX_32
416 bool "Support Cyrix processors" if PROCESSOR_SELECT
417 depends on M486 || M586 || M586TSC || M586MMX || (EXPERT && !64BIT)
419 This enables detection, tunings and quirks for Cyrix processors
421 You need this enabled if you want your kernel to run on a
422 Cyrix CPU. Disabling this option on other types of CPUs
423 makes the kernel a tiny bit smaller. Disabling it on a Cyrix
424 CPU might render the kernel unbootable.
430 bool "Support AMD processors" if PROCESSOR_SELECT
432 This enables detection, tunings and quirks for AMD processors
434 You need this enabled if you want your kernel to run on an
435 AMD CPU. Disabling this option on other types of CPUs
436 makes the kernel a tiny bit smaller. Disabling it on an AMD
437 CPU might render the kernel unbootable.
441 config CPU_SUP_CENTAUR
443 bool "Support Centaur processors" if PROCESSOR_SELECT
445 This enables detection, tunings and quirks for Centaur processors
447 You need this enabled if you want your kernel to run on a
448 Centaur CPU. Disabling this option on other types of CPUs
449 makes the kernel a tiny bit smaller. Disabling it on a Centaur
450 CPU might render the kernel unbootable.
454 config CPU_SUP_TRANSMETA_32
456 bool "Support Transmeta processors" if PROCESSOR_SELECT
459 This enables detection, tunings and quirks for Transmeta processors
461 You need this enabled if you want your kernel to run on a
462 Transmeta CPU. Disabling this option on other types of CPUs
463 makes the kernel a tiny bit smaller. Disabling it on a Transmeta
464 CPU might render the kernel unbootable.
468 config CPU_SUP_UMC_32
470 bool "Support UMC processors" if PROCESSOR_SELECT
471 depends on M486 || (EXPERT && !64BIT)
473 This enables detection, tunings and quirks for UMC processors
475 You need this enabled if you want your kernel to run on a
476 UMC CPU. Disabling this option on other types of CPUs
477 makes the kernel a tiny bit smaller. Disabling it on a UMC
478 CPU might render the kernel unbootable.