Linux kernel mirror (for testing)
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linux
1# SPDX-License-Identifier: GPL-2.0
2# Put here option for CPU selection and depending optimization
3choice
4 prompt "x86-32 Processor family"
5 depends on X86_32
6 default M686
7 help
8 This is the processor type of your CPU. This information is
9 used for optimizing purposes. In order to compile a kernel
10 that can run on all supported x86 CPU types (albeit not
11 optimally fast), you can specify "486" here.
12
13 Note that the 386 is no longer supported, this includes
14 AMD/Cyrix/Intel 386DX/DXL/SL/SLC/SX, Cyrix/TI 486DLC/DLC2,
15 UMC 486SX-S and the NexGen Nx586.
16
17 The kernel will not necessarily run on earlier architectures than
18 the one you have chosen, e.g. a Pentium optimized kernel will run on
19 a PPro, but not necessarily on a i486.
20
21 Here are the settings recommended for greatest speed:
22 - "486" for the AMD/Cyrix/IBM/Intel 486DX/DX2/DX4 or
23 SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or U5S.
24 - "586" for generic Pentium CPUs lacking the TSC
25 (time stamp counter) register.
26 - "Pentium-Classic" for the Intel Pentium.
27 - "Pentium-MMX" for the Intel Pentium MMX.
28 - "Pentium-Pro" for the Intel Pentium Pro.
29 - "Pentium-II" for the Intel Pentium II or pre-Coppermine Celeron.
30 - "Pentium-III" for the Intel Pentium III or Coppermine Celeron.
31 - "Pentium-4" for the Intel Pentium 4 or P4-based Celeron.
32 - "K6" for the AMD K6, K6-II and K6-III (aka K6-3D).
33 - "Athlon" for the AMD K7 family (Athlon/Duron/Thunderbird).
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 Atom" for the Atom-microarchitecture CPUs.
45
46 See each option's help text for additional details. If you don't know
47 what to do, choose "Pentium-Pro".
48
49config M486SX
50 bool "486SX"
51 depends on X86_32
52 help
53 Select this for an 486-class CPU without an FPU such as
54 AMD/Cyrix/IBM/Intel SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5S.
55
56config M486
57 bool "486DX"
58 depends on X86_32
59 help
60 Select this for an 486-class CPU such as AMD/Cyrix/IBM/Intel
61 486DX/DX2/DX4 and UMC U5D.
62
63config M586
64 bool "586/K5/5x86/6x86/6x86MX"
65 depends on X86_32
66 help
67 Select this for an 586 or 686 series processor such as the AMD K5,
68 the Cyrix 5x86, 6x86 and 6x86MX. This choice does not
69 assume the RDTSC (Read Time Stamp Counter) instruction.
70
71config M586TSC
72 bool "Pentium-Classic"
73 depends on X86_32
74 help
75 Select this for a Pentium Classic processor with the RDTSC (Read
76 Time Stamp Counter) instruction for benchmarking.
77
78config M586MMX
79 bool "Pentium-MMX"
80 depends on X86_32
81 help
82 Select this for a Pentium with the MMX graphics/multimedia
83 extended instructions.
84
85config M686
86 bool "Pentium-Pro"
87 depends on X86_32
88 help
89 Select this for Intel Pentium Pro chips. This enables the use of
90 Pentium Pro extended instructions, and disables the init-time guard
91 against the f00f bug found in earlier Pentiums.
92
93config MPENTIUMII
94 bool "Pentium-II/Celeron(pre-Coppermine)"
95 depends on X86_32
96 help
97 Select this for Intel chips based on the Pentium-II and
98 pre-Coppermine Celeron core. This option enables an unaligned
99 copy optimization, compiles the kernel with optimization flags
100 tailored for the chip, and applies any applicable Pentium Pro
101 optimizations.
102
103config MPENTIUMIII
104 bool "Pentium-III/Celeron(Coppermine)/Pentium-III Xeon"
105 depends on X86_32
106 help
107 Select this for Intel chips based on the Pentium-III and
108 Celeron-Coppermine core. This option enables use of some
109 extended prefetch instructions in addition to the Pentium II
110 extensions.
111
112config MPENTIUMM
113 bool "Pentium M/Pentium Dual Core/Core Solo/Core Duo"
114 depends on X86_32
115 help
116 Select this for Intel Pentium M (not Pentium-4 M)
117 "Merom" Core Solo/Duo notebook chips
118
119config MPENTIUM4
120 bool "Pentium-4/Celeron(P4-based)/Pentium-4 M/older Xeon"
121 depends on X86_32
122 help
123 Select this for Intel Pentium 4 chips. This includes the
124 Pentium 4, Pentium D, P4-based Celeron and Xeon, and
125 Pentium-4 M (not Pentium M) chips. This option enables compile
126 flags optimized for the chip, uses the correct cache line size, and
127 applies any applicable optimizations.
128
129 CPUIDs: F[0-6][1-A] (in /proc/cpuinfo show = cpu family : 15 )
130
131 Select this for:
132 Pentiums (Pentium 4, Pentium D, Celeron, Celeron D) corename:
133 -Willamette
134 -Northwood
135 -Mobile Pentium 4
136 -Mobile Pentium 4 M
137 -Extreme Edition (Gallatin)
138 Xeons (Intel Xeon, Xeon MP, Xeon LV, Xeon MV) corename:
139 -Foster
140 -Prestonia
141 -Gallatin
142
143config MK6
144 bool "K6/K6-II/K6-III"
145 depends on X86_32
146 help
147 Select this for an AMD K6-family processor. Enables use of
148 some extended instructions, and passes appropriate optimization
149 flags to GCC.
150
151config MK7
152 bool "Athlon/Duron/K7"
153 depends on X86_32
154 help
155 Select this for an AMD Athlon K7-family processor. Enables use of
156 some extended instructions, and passes appropriate optimization
157 flags to GCC.
158
159config MCRUSOE
160 bool "Crusoe"
161 depends on X86_32
162 help
163 Select this for a Transmeta Crusoe processor. Treats the processor
164 like a 586 with TSC, and sets some GCC optimization flags (like a
165 Pentium Pro with no alignment requirements).
166
167config MEFFICEON
168 bool "Efficeon"
169 depends on X86_32
170 help
171 Select this for a Transmeta Efficeon processor.
172
173config MWINCHIPC6
174 bool "Winchip-C6"
175 depends on X86_32
176 help
177 Select this for an IDT Winchip C6 chip. Linux and GCC
178 treat this chip as a 586TSC with some extended instructions
179 and alignment requirements.
180
181config MWINCHIP3D
182 bool "Winchip-2/Winchip-2A/Winchip-3"
183 depends on X86_32
184 help
185 Select this for an IDT Winchip-2, 2A or 3. Linux and GCC
186 treat this chip as a 586TSC with some extended instructions
187 and alignment requirements. Also enable out of order memory
188 stores for this CPU, which can increase performance of some
189 operations.
190
191config MELAN
192 bool "AMD Elan"
193 depends on X86_32
194 help
195 Select this for an AMD Elan processor.
196
197 Do not use this option for K6/Athlon/Opteron processors!
198
199config MGEODEGX1
200 bool "GeodeGX1"
201 depends on X86_32
202 help
203 Select this for a Geode GX1 (Cyrix MediaGX) chip.
204
205config MGEODE_LX
206 bool "Geode GX/LX"
207 depends on X86_32
208 help
209 Select this for AMD Geode GX and LX processors.
210
211config MCYRIXIII
212 bool "CyrixIII/VIA-C3"
213 depends on X86_32
214 help
215 Select this for a Cyrix III or C3 chip. Presently Linux and GCC
216 treat this chip as a generic 586. Whilst the CPU is 686 class,
217 it lacks the cmov extension which gcc assumes is present when
218 generating 686 code.
219 Note that Nehemiah (Model 9) and above will not boot with this
220 kernel due to them lacking the 3DNow! instructions used in earlier
221 incarnations of the CPU.
222
223config MVIAC3_2
224 bool "VIA C3-2 (Nehemiah)"
225 depends on X86_32
226 help
227 Select this for a VIA C3 "Nehemiah". Selecting this enables usage
228 of SSE and tells gcc to treat the CPU as a 686.
229 Note, this kernel will not boot on older (pre model 9) C3s.
230
231config MVIAC7
232 bool "VIA C7"
233 depends on X86_32
234 help
235 Select this for a VIA C7. Selecting this uses the correct cache
236 shift and tells gcc to treat the CPU as a 686.
237
238config MATOM
239 bool "Intel Atom"
240 help
241 Select this for the Intel Atom platform. Intel Atom CPUs have an
242 in-order pipelining architecture and thus can benefit from
243 accordingly optimized code. Use a recent GCC with specific Atom
244 support in order to fully benefit from selecting this option.
245
246endchoice
247
248config CC_HAS_MARCH_NATIVE
249 # This flag might not be available in cross-compilers:
250 def_bool $(cc-option, -march=native)
251 # LLVM 18 has an easily triggered internal compiler error in core
252 # networking code with '-march=native' on certain systems:
253 # https://github.com/llvm/llvm-project/issues/72026
254 # LLVM 19 introduces an optimization that resolves some high stack
255 # usage warnings that only appear wth '-march=native'.
256 depends on CC_IS_GCC || CLANG_VERSION >= 190100
257
258config X86_NATIVE_CPU
259 bool "Build and optimize for local/native CPU"
260 depends on X86_64
261 depends on CC_HAS_MARCH_NATIVE
262 help
263 Optimize for the current CPU used to compile the kernel.
264 Use this option if you intend to build the kernel for your
265 local machine.
266
267 Note that such a kernel might not work optimally on a
268 different x86 machine.
269
270 If unsure, say N.
271
272config X86_GENERIC
273 bool "Generic x86 support"
274 depends on X86_32
275 help
276 Instead of just including optimizations for the selected
277 x86 variant (e.g. PII, Crusoe or Athlon), include some more
278 generic optimizations as well. This will make the kernel
279 perform better on x86 CPUs other than that selected.
280
281 This is really intended for distributors who need more
282 generic optimizations.
283
284#
285# Define implied options from the CPU selection here
286config X86_INTERNODE_CACHE_SHIFT
287 int
288 default "12" if X86_VSMP
289 default X86_L1_CACHE_SHIFT
290
291config X86_L1_CACHE_SHIFT
292 int
293 default "7" if MPENTIUM4
294 default "6" if MK7 || MPENTIUMM || MATOM || MVIAC7 || X86_GENERIC || X86_64
295 default "4" if MELAN || M486SX || M486 || MGEODEGX1
296 default "5" if MWINCHIP3D || MWINCHIPC6 || MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODE_LX
297
298config X86_F00F_BUG
299 def_bool y
300 depends on M586MMX || M586TSC || M586 || M486SX || M486
301
302config X86_INVD_BUG
303 def_bool y
304 depends on M486SX || M486
305
306config X86_ALIGNMENT_16
307 def_bool y
308 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MELAN || MK6 || M586MMX || M586TSC || M586 || M486SX || M486 || MVIAC3_2 || MGEODEGX1
309
310config X86_INTEL_USERCOPY
311 def_bool y
312 depends on MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M586MMX || X86_GENERIC || MK7 || MEFFICEON
313
314config X86_USE_PPRO_CHECKSUM
315 def_bool y
316 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MEFFICEON || MGEODE_LX || MATOM
317
318config X86_TSC
319 def_bool y
320 depends on (MWINCHIP3D || MCRUSOE || MEFFICEON || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || MVIAC3_2 || MVIAC7 || MGEODEGX1 || MGEODE_LX || MATOM) || X86_64
321
322config X86_HAVE_PAE
323 def_bool y
324 depends on MCRUSOE || MEFFICEON || MCYRIXIII || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC7 || MATOM || X86_64
325
326config X86_CX8
327 def_bool y
328 depends on X86_HAVE_PAE || M586TSC || M586MMX || MK6 || MK7 || MGEODEGX1 || MGEODE_LX
329
330# this should be set for all -march=.. options where the compiler
331# generates cmov.
332config X86_CMOV
333 def_bool y
334 depends on (MK7 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || MATOM || MGEODE_LX || X86_64)
335
336config X86_MINIMUM_CPU_FAMILY
337 int
338 default "64" if X86_64
339 default "6" if X86_32 && (MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MEFFICEON || MATOM || MK7)
340 default "5" if X86_32 && X86_CX8
341 default "4"
342
343config X86_DEBUGCTLMSR
344 def_bool y
345 depends on !(MK6 || MWINCHIPC6 || MWINCHIP3D || MCYRIXIII || M586MMX || M586TSC || M586 || M486SX || M486) && !UML
346
347config IA32_FEAT_CTL
348 def_bool y
349 depends on CPU_SUP_INTEL || CPU_SUP_CENTAUR || CPU_SUP_ZHAOXIN
350
351config X86_VMX_FEATURE_NAMES
352 def_bool y
353 depends on IA32_FEAT_CTL
354
355menuconfig PROCESSOR_SELECT
356 bool "Supported processor vendors" if EXPERT
357 help
358 This lets you choose what x86 vendor support code your kernel
359 will include.
360
361config BROADCAST_TLB_FLUSH
362 def_bool y
363 depends on CPU_SUP_AMD && 64BIT
364
365config CPU_SUP_INTEL
366 default y
367 bool "Support Intel processors" if PROCESSOR_SELECT
368 help
369 This enables detection, tunings and quirks for Intel processors
370
371 You need this enabled if you want your kernel to run on an
372 Intel CPU. Disabling this option on other types of CPUs
373 makes the kernel a tiny bit smaller. Disabling it on an Intel
374 CPU might render the kernel unbootable.
375
376 If unsure, say N.
377
378config CPU_SUP_CYRIX_32
379 default y
380 bool "Support Cyrix processors" if PROCESSOR_SELECT
381 depends on M486SX || M486 || M586 || M586TSC || M586MMX || (EXPERT && !64BIT)
382 help
383 This enables detection, tunings and quirks for Cyrix processors
384
385 You need this enabled if you want your kernel to run on a
386 Cyrix CPU. Disabling this option on other types of CPUs
387 makes the kernel a tiny bit smaller. Disabling it on a Cyrix
388 CPU might render the kernel unbootable.
389
390 If unsure, say N.
391
392config CPU_SUP_AMD
393 default y
394 bool "Support AMD processors" if PROCESSOR_SELECT
395 help
396 This enables detection, tunings and quirks for AMD processors
397
398 You need this enabled if you want your kernel to run on an
399 AMD CPU. Disabling this option on other types of CPUs
400 makes the kernel a tiny bit smaller. Disabling it on an AMD
401 CPU might render the kernel unbootable.
402
403 If unsure, say N.
404
405config CPU_SUP_HYGON
406 default y
407 bool "Support Hygon processors" if PROCESSOR_SELECT
408 select CPU_SUP_AMD
409 help
410 This enables detection, tunings and quirks for Hygon processors
411
412 You need this enabled if you want your kernel to run on an
413 Hygon CPU. Disabling this option on other types of CPUs
414 makes the kernel a tiny bit smaller. Disabling it on an Hygon
415 CPU might render the kernel unbootable.
416
417 If unsure, say N.
418
419config CPU_SUP_CENTAUR
420 default y
421 bool "Support Centaur processors" if PROCESSOR_SELECT
422 help
423 This enables detection, tunings and quirks for Centaur processors
424
425 You need this enabled if you want your kernel to run on a
426 Centaur CPU. Disabling this option on other types of CPUs
427 makes the kernel a tiny bit smaller. Disabling it on a Centaur
428 CPU might render the kernel unbootable.
429
430 If unsure, say N.
431
432config CPU_SUP_TRANSMETA_32
433 default y
434 bool "Support Transmeta processors" if PROCESSOR_SELECT
435 depends on !64BIT
436 help
437 This enables detection, tunings and quirks for Transmeta processors
438
439 You need this enabled if you want your kernel to run on a
440 Transmeta CPU. Disabling this option on other types of CPUs
441 makes the kernel a tiny bit smaller. Disabling it on a Transmeta
442 CPU might render the kernel unbootable.
443
444 If unsure, say N.
445
446config CPU_SUP_UMC_32
447 default y
448 bool "Support UMC processors" if PROCESSOR_SELECT
449 depends on M486SX || M486 || (EXPERT && !64BIT)
450 help
451 This enables detection, tunings and quirks for UMC processors
452
453 You need this enabled if you want your kernel to run on a
454 UMC CPU. Disabling this option on other types of CPUs
455 makes the kernel a tiny bit smaller. Disabling it on a UMC
456 CPU might render the kernel unbootable.
457
458 If unsure, say N.
459
460config CPU_SUP_ZHAOXIN
461 default y
462 bool "Support Zhaoxin processors" if PROCESSOR_SELECT
463 help
464 This enables detection, tunings and quirks for Zhaoxin processors
465
466 You need this enabled if you want your kernel to run on a
467 Zhaoxin CPU. Disabling this option on other types of CPUs
468 makes the kernel a tiny bit smaller. Disabling it on a Zhaoxin
469 CPU might render the kernel unbootable.
470
471 If unsure, say N.
472
473config CPU_SUP_VORTEX_32
474 default y
475 bool "Support Vortex processors" if PROCESSOR_SELECT
476 depends on X86_32
477 help
478 This enables detection, tunings and quirks for Vortex processors
479
480 You need this enabled if you want your kernel to run on a
481 Vortex CPU. Disabling this option on other types of CPUs
482 makes the kernel a tiny bit smaller.
483
484 If unsure, say N.