1 # Put here option for CPU selection and depending optimization
3 prompt "Processor family"
5 default GENERIC_CPU if X86_64
11 This is the processor type of your CPU. This information is
12 used for optimizing purposes. In order to compile a kernel
13 that can run on all supported x86 CPU types (albeit not
14 optimally fast), you can specify "486" here.
16 Note that the 386 is no longer supported, this includes
17 AMD/Cyrix/Intel 386DX/DXL/SL/SLC/SX, Cyrix/TI 486DLC/DLC2,
18 UMC 486SX-S and the NexGen Nx586.
20 The kernel will not necessarily run on earlier architectures than
21 the one you have chosen, e.g. a Pentium optimized kernel will run on
22 a PPro, but not necessarily on a i486.
24 Here are the settings recommended for greatest speed:
25 - "486" for the AMD/Cyrix/IBM/Intel 486DX/DX2/DX4 or
26 SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or U5S.
27 - "586" for generic Pentium CPUs lacking the TSC
28 (time stamp counter) register.
29 - "Pentium-Classic" for the Intel Pentium.
30 - "Pentium-MMX" for the Intel Pentium MMX.
31 - "Pentium-Pro" for the Intel Pentium Pro.
32 - "Pentium-II" for the Intel Pentium II or pre-Coppermine Celeron.
33 - "Pentium-III" for the Intel Pentium III or Coppermine Celeron.
34 - "Pentium-4" for the Intel Pentium 4 or P4-based Celeron.
35 - "K6" for the AMD K6, K6-II and K6-III (aka K6-3D).
36 - "Athlon" for the AMD K7 family (Athlon/Duron/Thunderbird).
37 - "Crusoe" for the Transmeta Crusoe series.
38 - "Efficeon" for the Transmeta Efficeon series.
39 - "Winchip-C6" for original IDT Winchip.
40 - "Winchip-2" for IDT Winchips with 3dNow! capabilities.
41 - "GeodeGX1" for Geode GX1 (Cyrix MediaGX).
42 - "Geode GX/LX" For AMD Geode GX and LX processors.
43 - "CyrixIII/VIA C3" for VIA Cyrix III or VIA C3.
44 - "VIA C3-2" for VIA C3-2 "Nehemiah" (model 9 and above).
45 - "VIA C7" for VIA C7.
47 If you don't know what to do, choose "486".
50 bool "586/K5/5x86/6x86/6x86MX"
53 Select this for an 586 or 686 series processor such as the AMD K5,
54 the Cyrix 5x86, 6x86 and 6x86MX. This choice does not
55 assume the RDTSC (Read Time Stamp Counter) instruction.
58 bool "Pentium-Classic"
61 Select this for a Pentium Classic processor with the RDTSC (Read
62 Time Stamp Counter) instruction for benchmarking.
68 Select this for a Pentium with the MMX graphics/multimedia
69 extended instructions.
75 Select this for Intel Pentium Pro chips. This enables the use of
76 Pentium Pro extended instructions, and disables the init-time guard
77 against the f00f bug found in earlier Pentiums.
80 bool "Pentium-II/Celeron(pre-Coppermine)"
83 Select this for Intel chips based on the Pentium-II and
84 pre-Coppermine Celeron core. This option enables an unaligned
85 copy optimization, compiles the kernel with optimization flags
86 tailored for the chip, and applies any applicable Pentium Pro
90 bool "Pentium-III/Celeron(Coppermine)/Pentium-III Xeon"
93 Select this for Intel chips based on the Pentium-III and
94 Celeron-Coppermine core. This option enables use of some
95 extended prefetch instructions in addition to the Pentium II
102 Select this for Intel Pentium M (not Pentium-4 M)
106 bool "Pentium-4/Celeron(P4-based)/Pentium-4 M/older Xeon"
109 Select this for Intel Pentium 4 chips. This includes the
110 Pentium 4, Pentium D, P4-based Celeron and Xeon, and
111 Pentium-4 M (not Pentium M) chips. This option enables compile
112 flags optimized for the chip, uses the correct cache line size, and
113 applies any applicable optimizations.
115 CPUIDs: F[0-6][1-A] (in /proc/cpuinfo show = cpu family : 15 )
118 Pentiums (Pentium 4, Pentium D, Celeron, Celeron D) corename:
123 -Extreme Edition (Gallatin)
129 Xeons (Intel Xeon, Xeon MP, Xeon LV, Xeon MV) corename:
142 bool "K6/K6-II/K6-III"
145 Select this for an AMD K6-family processor. Enables use of
146 some extended instructions, and passes appropriate optimization
150 bool "Athlon/Duron/K7"
153 Select this for an AMD Athlon K7-family processor. Enables use of
154 some extended instructions, and passes appropriate optimization
158 bool "Opteron/Athlon64/Hammer/K8"
160 Select this for an AMD Opteron or Athlon64 Hammer-family processor.
161 Enables use of some extended instructions, and passes appropriate
162 optimization flags to GCC.
168 Select this for a Transmeta Crusoe processor. Treats the processor
169 like a 586 with TSC, and sets some GCC optimization flags (like a
170 Pentium Pro with no alignment requirements).
176 Select this for a Transmeta Efficeon processor.
182 Select this for an IDT Winchip C6 chip. Linux and GCC
183 treat this chip as a 586TSC with some extended instructions
184 and alignment requirements.
187 bool "Winchip-2/Winchip-2A/Winchip-3"
190 Select this for an IDT Winchip-2, 2A or 3. Linux and GCC
191 treat this chip as a 586TSC with some extended instructions
192 and alignment requirements. Also enable out of order memory
193 stores for this CPU, which can increase performance of some
200 Select this for an AMD Elan processor.
202 Do not use this option for K6/Athlon/Opteron processors!
208 Select this for a Geode GX1 (Cyrix MediaGX) chip.
214 Select this for AMD Geode GX and LX processors.
217 bool "CyrixIII/VIA-C3"
220 Select this for a Cyrix III or C3 chip. Presently Linux and GCC
221 treat this chip as a generic 586. Whilst the CPU is 686 class,
222 it lacks the cmov extension which gcc assumes is present when
224 Note that Nehemiah (Model 9) and above will not boot with this
225 kernel due to them lacking the 3DNow! instructions used in earlier
226 incarnations of the CPU.
229 bool "VIA C3-2 (Nehemiah)"
232 Select this for a VIA C3 "Nehemiah". Selecting this enables usage
233 of SSE and tells gcc to treat the CPU as a 686.
234 Note, this kernel will not boot on older (pre model 9) C3s.
240 Select this for a VIA C7. Selecting this uses the correct cache
241 shift and tells gcc to treat the CPU as a 686.
244 bool "Intel P4 / older Netburst based Xeon"
247 Optimize for Intel Pentium 4, Pentium D and older Nocona/Dempsey
248 Xeon CPUs with Intel 64bit which is compatible with x86-64.
249 Note that the latest Xeons (Xeon 51xx and 53xx) are not based on the
250 Netburst core and shouldn't use this option. You can distinguish them
251 using the cpu family field
252 in /proc/cpuinfo. Family 15 is an older Xeon, Family 6 a newer one.
255 bool "Core 2/newer Xeon"
258 Select this for Intel Core 2 and newer Core 2 Xeons (Xeon 51xx and
259 53xx) CPUs. You can distinguish newer from older Xeons by the CPU
260 family in /proc/cpuinfo. Newer ones have 6 and older ones 15
267 Select this for the Intel Atom platform. Intel Atom CPUs have an
268 in-order pipelining architecture and thus can benefit from
269 accordingly optimized code. Use a recent GCC with specific Atom
270 support in order to fully benefit from selecting this option.
273 bool "Generic-x86-64"
277 Run equally well on all x86-64 CPUs.
282 bool "Generic x86 support"
285 Instead of just including optimizations for the selected
286 x86 variant (e.g. PII, Crusoe or Athlon), include some more
287 generic optimizations as well. This will make the kernel
288 perform better on x86 CPUs other than that selected.
290 This is really intended for distributors who need more
291 generic optimizations.
294 # Define implied options from the CPU selection here
295 config X86_INTERNODE_CACHE_SHIFT
297 default "12" if X86_VSMP
298 default X86_L1_CACHE_SHIFT
300 config X86_L1_CACHE_SHIFT
302 default "7" if MPENTIUM4 || MPSC
303 default "6" if MK7 || MK8 || MPENTIUMM || MCORE2 || MATOM || MVIAC7 || X86_GENERIC || GENERIC_CPU
304 default "4" if MELAN || M486 || MGEODEGX1
305 default "5" if MWINCHIP3D || MWINCHIPC6 || MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODE_LX
307 config X86_PPRO_FENCE
308 bool "PentiumPro memory ordering errata workaround"
309 depends on M686 || M586MMX || M586TSC || M586 || M486 || MGEODEGX1
311 Old PentiumPro multiprocessor systems had errata that could cause
312 memory operations to violate the x86 ordering standard in rare cases.
313 Enabling this option will attempt to work around some (but not all)
314 occurrences of this problem, at the cost of much heavier spinlock and
315 memory barrier operations.
317 If unsure, say n here. Even distro kernels should think twice before
318 enabling this: there are few systems, and an unlikely bug.
322 depends on M586MMX || M586TSC || M586 || M486
328 config X86_ALIGNMENT_16
330 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MELAN || MK6 || M586MMX || M586TSC || M586 || M486 || MVIAC3_2 || MGEODEGX1
332 config X86_INTEL_USERCOPY
334 depends on MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M586MMX || X86_GENERIC || MK8 || MK7 || MEFFICEON || MCORE2
336 config X86_USE_PPRO_CHECKSUM
338 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2 || MVIAC7 || MEFFICEON || MGEODE_LX || MCORE2 || MATOM
342 depends on (MCYRIXIII || MK7 || MGEODE_LX) && !UML
346 depends on (MWINCHIP3D || MWINCHIPC6) && MTRR
349 # P6_NOPs are a relatively minor optimization that require a family >=
350 # 6 processor, except that it is broken on certain VIA chips.
351 # Furthermore, AMD chips prefer a totally different sequence of NOPs
352 # (which work on all CPUs). In addition, it looks like Virtual PC
353 # does not understand them.
355 # As a result, disallow these if we're not compiling for X86_64 (these
356 # NOPs do work on all x86-64 capable chips); the list of processors in
357 # the right-hand clause are the cores that benefit from this optimization.
362 depends on (MCORE2 || MPENTIUM4 || MPSC)
366 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_NUMAQ) || X86_64
370 depends on X86_PAE || X86_64 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MATOM
372 # this should be set for all -march=.. options where the compiler
376 depends on (MK8 || MK7 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM || MGEODE_LX)
378 config X86_MINIMUM_CPU_FAMILY
380 default "64" if X86_64
381 default "6" if X86_32 && X86_P6_NOP
382 default "5" if X86_32 && X86_CMPXCHG64
385 config X86_DEBUGCTLMSR
387 depends on !(MK6 || MWINCHIPC6 || MWINCHIP3D || MCYRIXIII || M586MMX || M586TSC || M586 || M486) && !UML
389 menuconfig PROCESSOR_SELECT
390 bool "Supported processor vendors" if EXPERT
392 This lets you choose what x86 vendor support code your kernel
397 bool "Support Intel processors" if PROCESSOR_SELECT
399 This enables detection, tunings and quirks for Intel processors
401 You need this enabled if you want your kernel to run on an
402 Intel CPU. Disabling this option on other types of CPUs
403 makes the kernel a tiny bit smaller. Disabling it on an Intel
404 CPU might render the kernel unbootable.
408 config CPU_SUP_CYRIX_32
410 bool "Support Cyrix processors" if PROCESSOR_SELECT
411 depends on M486 || M586 || M586TSC || M586MMX || (EXPERT && !64BIT)
413 This enables detection, tunings and quirks for Cyrix processors
415 You need this enabled if you want your kernel to run on a
416 Cyrix CPU. Disabling this option on other types of CPUs
417 makes the kernel a tiny bit smaller. Disabling it on a Cyrix
418 CPU might render the kernel unbootable.
424 bool "Support AMD processors" if PROCESSOR_SELECT
426 This enables detection, tunings and quirks for AMD processors
428 You need this enabled if you want your kernel to run on an
429 AMD CPU. Disabling this option on other types of CPUs
430 makes the kernel a tiny bit smaller. Disabling it on an AMD
431 CPU might render the kernel unbootable.
435 config CPU_SUP_CENTAUR
437 bool "Support Centaur processors" if PROCESSOR_SELECT
439 This enables detection, tunings and quirks for Centaur processors
441 You need this enabled if you want your kernel to run on a
442 Centaur CPU. Disabling this option on other types of CPUs
443 makes the kernel a tiny bit smaller. Disabling it on a Centaur
444 CPU might render the kernel unbootable.
448 config CPU_SUP_TRANSMETA_32
450 bool "Support Transmeta processors" if PROCESSOR_SELECT
453 This enables detection, tunings and quirks for Transmeta processors
455 You need this enabled if you want your kernel to run on a
456 Transmeta CPU. Disabling this option on other types of CPUs
457 makes the kernel a tiny bit smaller. Disabling it on a Transmeta
458 CPU might render the kernel unbootable.
462 config CPU_SUP_UMC_32
464 bool "Support UMC processors" if PROCESSOR_SELECT
465 depends on M486 || (EXPERT && !64BIT)
467 This enables detection, tunings and quirks for UMC processors
469 You need this enabled if you want your kernel to run on a
470 UMC CPU. Disabling this option on other types of CPUs
471 makes the kernel a tiny bit smaller. Disabling it on a UMC
472 CPU might render the kernel unbootable.