treewide: replace '---help---' in Kconfig files with 'help'
[linux-block.git] / arch / x86 / Kconfig.cpu
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b2441318 1# SPDX-License-Identifier: GPL-2.0
96d55b88 2# Put here option for CPU selection and depending optimization
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3choice
4 prompt "Processor family"
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5 default M686 if X86_32
6 default GENERIC_CPU if X86_64
a7f7f624 7 help
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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,
11af32b6 15 UMC 486SX-S and the NexGen Nx586.
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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:
96d55b88 22 - "486" for the AMD/Cyrix/IBM/Intel 486DX/DX2/DX4 or
221836e9 23 SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or U5S.
96d55b88 24 - "586" for generic Pentium CPUs lacking the TSC
221836e9 25 (time stamp counter) register.
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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).
221836e9 34 - "Opteron/Athlon64/Hammer/K8" for all K8 and newer AMD CPUs.
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35 - "Crusoe" for the Transmeta Crusoe series.
36 - "Efficeon" for the Transmeta Efficeon series.
37 - "Winchip-C6" for original IDT Winchip.
69d45dd1 38 - "Winchip-2" for IDT Winchips with 3dNow! capabilities.
221836e9 39 - "AMD Elan" for the 32-bit AMD Elan embedded CPU.
96d55b88 40 - "GeodeGX1" for Geode GX1 (Cyrix MediaGX).
f90b8116 41 - "Geode GX/LX" For AMD Geode GX and LX processors.
96d55b88 42 - "CyrixIII/VIA C3" for VIA Cyrix III or VIA C3.
48a1204c 43 - "VIA C3-2" for VIA C3-2 "Nehemiah" (model 9 and above).
0949be35 44 - "VIA C7" for VIA C7.
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45 - "Intel P4" for the Pentium 4/Netburst microarchitecture.
46 - "Core 2/newer Xeon" for all core2 and newer Intel CPUs.
47 - "Intel Atom" for the Atom-microarchitecture CPUs.
48 - "Generic-x86-64" for a kernel which runs on any x86-64 CPU.
49
50 See each option's help text for additional details. If you don't know
51 what to do, choose "486".
96d55b88 52
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53config M486SX
54 bool "486SX"
55 depends on X86_32
a7f7f624 56 help
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57 Select this for an 486-class CPU without an FPU such as
58 AMD/Cyrix/IBM/Intel SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5S.
59
221836e9 60config M486
87d6021b 61 bool "486DX"
221836e9 62 depends on X86_32
a7f7f624 63 help
221836e9 64 Select this for an 486-class CPU such as AMD/Cyrix/IBM/Intel
87d6021b 65 486DX/DX2/DX4 and UMC U5D.
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66
67config M586
68 bool "586/K5/5x86/6x86/6x86MX"
1032c0ba 69 depends on X86_32
a7f7f624 70 help
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71 Select this for an 586 or 686 series processor such as the AMD K5,
72 the Cyrix 5x86, 6x86 and 6x86MX. This choice does not
73 assume the RDTSC (Read Time Stamp Counter) instruction.
74
75config M586TSC
76 bool "Pentium-Classic"
1032c0ba 77 depends on X86_32
a7f7f624 78 help
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79 Select this for a Pentium Classic processor with the RDTSC (Read
80 Time Stamp Counter) instruction for benchmarking.
81
82config M586MMX
83 bool "Pentium-MMX"
1032c0ba 84 depends on X86_32
a7f7f624 85 help
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86 Select this for a Pentium with the MMX graphics/multimedia
87 extended instructions.
88
89config M686
90 bool "Pentium-Pro"
1032c0ba 91 depends on X86_32
a7f7f624 92 help
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93 Select this for Intel Pentium Pro chips. This enables the use of
94 Pentium Pro extended instructions, and disables the init-time guard
95 against the f00f bug found in earlier Pentiums.
96
97config MPENTIUMII
98 bool "Pentium-II/Celeron(pre-Coppermine)"
1032c0ba 99 depends on X86_32
a7f7f624 100 help
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101 Select this for Intel chips based on the Pentium-II and
102 pre-Coppermine Celeron core. This option enables an unaligned
103 copy optimization, compiles the kernel with optimization flags
104 tailored for the chip, and applies any applicable Pentium Pro
105 optimizations.
106
107config MPENTIUMIII
108 bool "Pentium-III/Celeron(Coppermine)/Pentium-III Xeon"
1032c0ba 109 depends on X86_32
a7f7f624 110 help
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111 Select this for Intel chips based on the Pentium-III and
112 Celeron-Coppermine core. This option enables use of some
113 extended prefetch instructions in addition to the Pentium II
114 extensions.
115
116config MPENTIUMM
117 bool "Pentium M"
1032c0ba 118 depends on X86_32
a7f7f624 119 help
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120 Select this for Intel Pentium M (not Pentium-4 M)
121 notebook chips.
122
123config MPENTIUM4
c55d92d1 124 bool "Pentium-4/Celeron(P4-based)/Pentium-4 M/older Xeon"
1032c0ba 125 depends on X86_32
a7f7f624 126 help
96d55b88 127 Select this for Intel Pentium 4 chips. This includes the
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128 Pentium 4, Pentium D, P4-based Celeron and Xeon, and
129 Pentium-4 M (not Pentium M) chips. This option enables compile
130 flags optimized for the chip, uses the correct cache line size, and
131 applies any applicable optimizations.
132
133 CPUIDs: F[0-6][1-A] (in /proc/cpuinfo show = cpu family : 15 )
134
135 Select this for:
136 Pentiums (Pentium 4, Pentium D, Celeron, Celeron D) corename:
137 -Willamette
138 -Northwood
139 -Mobile Pentium 4
140 -Mobile Pentium 4 M
141 -Extreme Edition (Gallatin)
142 -Prescott
143 -Prescott 2M
144 -Cedar Mill
145 -Presler
146 -Smithfiled
147 Xeons (Intel Xeon, Xeon MP, Xeon LV, Xeon MV) corename:
148 -Foster
149 -Prestonia
150 -Gallatin
151 -Nocona
152 -Irwindale
153 -Cranford
154 -Potomac
155 -Paxville
156 -Dempsey
157
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158
159config MK6
160 bool "K6/K6-II/K6-III"
1032c0ba 161 depends on X86_32
a7f7f624 162 help
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163 Select this for an AMD K6-family processor. Enables use of
164 some extended instructions, and passes appropriate optimization
165 flags to GCC.
166
167config MK7
168 bool "Athlon/Duron/K7"
1032c0ba 169 depends on X86_32
a7f7f624 170 help
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171 Select this for an AMD Athlon K7-family processor. Enables use of
172 some extended instructions, and passes appropriate optimization
173 flags to GCC.
174
175config MK8
176 bool "Opteron/Athlon64/Hammer/K8"
a7f7f624 177 help
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178 Select this for an AMD Opteron or Athlon64 Hammer-family processor.
179 Enables use of some extended instructions, and passes appropriate
180 optimization flags to GCC.
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181
182config MCRUSOE
183 bool "Crusoe"
1032c0ba 184 depends on X86_32
a7f7f624 185 help
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186 Select this for a Transmeta Crusoe processor. Treats the processor
187 like a 586 with TSC, and sets some GCC optimization flags (like a
188 Pentium Pro with no alignment requirements).
189
190config MEFFICEON
191 bool "Efficeon"
1032c0ba 192 depends on X86_32
a7f7f624 193 help
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194 Select this for a Transmeta Efficeon processor.
195
196config MWINCHIPC6
197 bool "Winchip-C6"
1032c0ba 198 depends on X86_32
a7f7f624 199 help
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200 Select this for an IDT Winchip C6 chip. Linux and GCC
201 treat this chip as a 586TSC with some extended instructions
202 and alignment requirements.
203
96d55b88 204config MWINCHIP3D
69d45dd1 205 bool "Winchip-2/Winchip-2A/Winchip-3"
1032c0ba 206 depends on X86_32
a7f7f624 207 help
69d45dd1 208 Select this for an IDT Winchip-2, 2A or 3. Linux and GCC
96d55b88 209 treat this chip as a 586TSC with some extended instructions
3dde6ad8 210 and alignment requirements. Also enable out of order memory
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211 stores for this CPU, which can increase performance of some
212 operations.
213
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214config MELAN
215 bool "AMD Elan"
216 depends on X86_32
a7f7f624 217 help
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218 Select this for an AMD Elan processor.
219
220 Do not use this option for K6/Athlon/Opteron processors!
221
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222config MGEODEGX1
223 bool "GeodeGX1"
1032c0ba 224 depends on X86_32
a7f7f624 225 help
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226 Select this for a Geode GX1 (Cyrix MediaGX) chip.
227
f90b8116 228config MGEODE_LX
96daa8cd 229 bool "Geode GX/LX"
1032c0ba 230 depends on X86_32
a7f7f624 231 help
96daa8cd 232 Select this for AMD Geode GX and LX processors.
f90b8116 233
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234config MCYRIXIII
235 bool "CyrixIII/VIA-C3"
1032c0ba 236 depends on X86_32
a7f7f624 237 help
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238 Select this for a Cyrix III or C3 chip. Presently Linux and GCC
239 treat this chip as a generic 586. Whilst the CPU is 686 class,
240 it lacks the cmov extension which gcc assumes is present when
241 generating 686 code.
242 Note that Nehemiah (Model 9) and above will not boot with this
243 kernel due to them lacking the 3DNow! instructions used in earlier
244 incarnations of the CPU.
245
246config MVIAC3_2
247 bool "VIA C3-2 (Nehemiah)"
1032c0ba 248 depends on X86_32
a7f7f624 249 help
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250 Select this for a VIA C3 "Nehemiah". Selecting this enables usage
251 of SSE and tells gcc to treat the CPU as a 686.
252 Note, this kernel will not boot on older (pre model 9) C3s.
253
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254config MVIAC7
255 bool "VIA C7"
1032c0ba 256 depends on X86_32
a7f7f624 257 help
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258 Select this for a VIA C7. Selecting this uses the correct cache
259 shift and tells gcc to treat the CPU as a 686.
260
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261config MPSC
262 bool "Intel P4 / older Netburst based Xeon"
263 depends on X86_64
a7f7f624 264 help
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265 Optimize for Intel Pentium 4, Pentium D and older Nocona/Dempsey
266 Xeon CPUs with Intel 64bit which is compatible with x86-64.
267 Note that the latest Xeons (Xeon 51xx and 53xx) are not based on the
96daa8cd 268 Netburst core and shouldn't use this option. You can distinguish them
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269 using the cpu family field
270 in /proc/cpuinfo. Family 15 is an older Xeon, Family 6 a newer one.
271
272config MCORE2
273 bool "Core 2/newer Xeon"
a7f7f624 274 help
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275
276 Select this for Intel Core 2 and newer Core 2 Xeons (Xeon 51xx and
277 53xx) CPUs. You can distinguish newer from older Xeons by the CPU
278 family in /proc/cpuinfo. Newer ones have 6 and older ones 15
279 (not a typo)
1032c0ba 280
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281config MATOM
282 bool "Intel Atom"
a7f7f624 283 help
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284
285 Select this for the Intel Atom platform. Intel Atom CPUs have an
286 in-order pipelining architecture and thus can benefit from
287 accordingly optimized code. Use a recent GCC with specific Atom
288 support in order to fully benefit from selecting this option.
289
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290config GENERIC_CPU
291 bool "Generic-x86-64"
292 depends on X86_64
a7f7f624 293 help
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294 Generic x86-64 CPU.
295 Run equally well on all x86-64 CPUs.
296
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297endchoice
298
299config X86_GENERIC
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300 bool "Generic x86 support"
301 depends on X86_32
a7f7f624 302 help
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303 Instead of just including optimizations for the selected
304 x86 variant (e.g. PII, Crusoe or Athlon), include some more
305 generic optimizations as well. This will make the kernel
306 perform better on x86 CPUs other than that selected.
307
308 This is really intended for distributors who need more
309 generic optimizations.
310
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311#
312# Define implied options from the CPU selection here
350f8f56 313config X86_INTERNODE_CACHE_SHIFT
1032c0ba 314 int
350f8f56 315 default "12" if X86_VSMP
350f8f56 316 default X86_L1_CACHE_SHIFT
1032c0ba 317
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318config X86_L1_CACHE_SHIFT
319 int
0a2a18b7 320 default "7" if MPENTIUM4 || MPSC
350f8f56 321 default "6" if MK7 || MK8 || MPENTIUMM || MCORE2 || MATOM || MVIAC7 || X86_GENERIC || GENERIC_CPU
87d6021b 322 default "4" if MELAN || M486SX || M486 || MGEODEGX1
69d45dd1 323 default "5" if MWINCHIP3D || MWINCHIPC6 || MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODE_LX
96d55b88 324
96d55b88 325config X86_F00F_BUG
96daa8cd 326 def_bool y
87d6021b 327 depends on M586MMX || M586TSC || M586 || M486SX || M486
96d55b88 328
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329config X86_INVD_BUG
330 def_bool y
87d6021b 331 depends on M486SX || M486
40d2e763 332
96d55b88 333config X86_ALIGNMENT_16
96daa8cd 334 def_bool y
87d6021b 335 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MELAN || MK6 || M586MMX || M586TSC || M586 || M486SX || M486 || MVIAC3_2 || MGEODEGX1
96d55b88 336
96d55b88 337config X86_INTEL_USERCOPY
96daa8cd 338 def_bool y
c55d92d1 339 depends on MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M586MMX || X86_GENERIC || MK8 || MK7 || MEFFICEON || MCORE2
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340
341config X86_USE_PPRO_CHECKSUM
96daa8cd 342 def_bool y
1eda75c1 343 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2 || MVIAC7 || MEFFICEON || MGEODE_LX || MCORE2 || MATOM
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344
345config X86_USE_3DNOW
96daa8cd 346 def_bool y
1b4ad242 347 depends on (MCYRIXIII || MK7 || MGEODE_LX) && !UML
96d55b88 348
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349#
350# P6_NOPs are a relatively minor optimization that require a family >=
351# 6 processor, except that it is broken on certain VIA chips.
352# Furthermore, AMD chips prefer a totally different sequence of NOPs
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353# (which work on all CPUs). In addition, it looks like Virtual PC
354# does not understand them.
355#
356# As a result, disallow these if we're not compiling for X86_64 (these
357# NOPs do work on all x86-64 capable chips); the list of processors in
358# the right-hand clause are the cores that benefit from this optimization.
959b3be6 359#
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360config X86_P6_NOP
361 def_bool y
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362 depends on X86_64
363 depends on (MCORE2 || MPENTIUM4 || MPSC)
7343b3b3 364
96d55b88 365config X86_TSC
96daa8cd 366 def_bool y
b5660ba7 367 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
c7f81c94 368
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369config X86_CMPXCHG64
370 def_bool y
f960cfd1 371 depends on X86_PAE || X86_64 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || M586TSC || M586MMX || MATOM || MGEODE_LX || MGEODEGX1 || MK6 || MK7 || MK8
f8096f92 372
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373# this should be set for all -march=.. options where the compiler
374# generates cmov.
375config X86_CMOV
96daa8cd 376 def_bool y
98059e34 377 depends on (MK8 || MK7 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM || MGEODE_LX)
c7f81c94 378
de32e041 379config X86_MINIMUM_CPU_FAMILY
c7f81c94 380 int
1032c0ba 381 default "64" if X86_64
25d76ac8 382 default "6" if X86_32 && (MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MEFFICEON || MATOM || MCRUSOE || MCORE2 || MK7 || MK8)
982d007a 383 default "5" if X86_32 && X86_CMPXCHG64
eb068e78 384 default "4"
c7f81c94 385
0a049bb0 386config X86_DEBUGCTLMSR
96daa8cd 387 def_bool y
87d6021b 388 depends on !(MK6 || MWINCHIPC6 || MWINCHIP3D || MCYRIXIII || M586MMX || M586TSC || M586 || M486SX || M486) && !UML
8d02c211 389
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390config IA32_FEAT_CTL
391 def_bool y
7d37953b 392 depends on CPU_SUP_INTEL || CPU_SUP_CENTAUR || CPU_SUP_ZHAOXIN
1db2a6e1 393
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394config X86_VMX_FEATURE_NAMES
395 def_bool y
396 depends on IA32_FEAT_CTL && X86_FEATURE_NAMES
397
8d02c211 398menuconfig PROCESSOR_SELECT
6a108a14 399 bool "Supported processor vendors" if EXPERT
a7f7f624 400 help
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401 This lets you choose what x86 vendor support code your kernel
402 will include.
403
879d792b 404config CPU_SUP_INTEL
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405 default y
406 bool "Support Intel processors" if PROCESSOR_SELECT
a7f7f624 407 help
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408 This enables detection, tunings and quirks for Intel processors
409
410 You need this enabled if you want your kernel to run on an
411 Intel CPU. Disabling this option on other types of CPUs
412 makes the kernel a tiny bit smaller. Disabling it on an Intel
413 CPU might render the kernel unbootable.
414
415 If unsure, say N.
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416
417config CPU_SUP_CYRIX_32
418 default y
419 bool "Support Cyrix processors" if PROCESSOR_SELECT
87d6021b 420 depends on M486SX || M486 || M586 || M586TSC || M586MMX || (EXPERT && !64BIT)
a7f7f624 421 help
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422 This enables detection, tunings and quirks for Cyrix processors
423
424 You need this enabled if you want your kernel to run on a
425 Cyrix CPU. Disabling this option on other types of CPUs
426 makes the kernel a tiny bit smaller. Disabling it on a Cyrix
427 CPU might render the kernel unbootable.
428
429 If unsure, say N.
8d02c211 430
ff73152c 431config CPU_SUP_AMD
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432 default y
433 bool "Support AMD processors" if PROCESSOR_SELECT
a7f7f624 434 help
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435 This enables detection, tunings and quirks for AMD processors
436
437 You need this enabled if you want your kernel to run on an
438 AMD CPU. Disabling this option on other types of CPUs
439 makes the kernel a tiny bit smaller. Disabling it on an AMD
440 CPU might render the kernel unbootable.
441
442 If unsure, say N.
8d02c211 443
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444config CPU_SUP_HYGON
445 default y
446 bool "Support Hygon processors" if PROCESSOR_SELECT
447 select CPU_SUP_AMD
448 help
449 This enables detection, tunings and quirks for Hygon processors
450
451 You need this enabled if you want your kernel to run on an
452 Hygon CPU. Disabling this option on other types of CPUs
453 makes the kernel a tiny bit smaller. Disabling it on an Hygon
454 CPU might render the kernel unbootable.
455
456 If unsure, say N.
457
48f4c485 458config CPU_SUP_CENTAUR
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459 default y
460 bool "Support Centaur processors" if PROCESSOR_SELECT
a7f7f624 461 help
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462 This enables detection, tunings and quirks for Centaur processors
463
464 You need this enabled if you want your kernel to run on a
465 Centaur CPU. Disabling this option on other types of CPUs
466 makes the kernel a tiny bit smaller. Disabling it on a Centaur
467 CPU might render the kernel unbootable.
468
469 If unsure, say N.
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470
471config CPU_SUP_TRANSMETA_32
472 default y
473 bool "Support Transmeta processors" if PROCESSOR_SELECT
474 depends on !64BIT
a7f7f624 475 help
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476 This enables detection, tunings and quirks for Transmeta processors
477
478 You need this enabled if you want your kernel to run on a
479 Transmeta CPU. Disabling this option on other types of CPUs
480 makes the kernel a tiny bit smaller. Disabling it on a Transmeta
481 CPU might render the kernel unbootable.
482
483 If unsure, say N.
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484
485config CPU_SUP_UMC_32
486 default y
487 bool "Support UMC processors" if PROCESSOR_SELECT
87d6021b 488 depends on M486SX || M486 || (EXPERT && !64BIT)
a7f7f624 489 help
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490 This enables detection, tunings and quirks for UMC processors
491
492 You need this enabled if you want your kernel to run on a
493 UMC CPU. Disabling this option on other types of CPUs
494 makes the kernel a tiny bit smaller. Disabling it on a UMC
495 CPU might render the kernel unbootable.
496
497 If unsure, say N.
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498
499config CPU_SUP_ZHAOXIN
500 default y
501 bool "Support Zhaoxin processors" if PROCESSOR_SELECT
502 help
503 This enables detection, tunings and quirks for Zhaoxin processors
504
505 You need this enabled if you want your kernel to run on a
506 Zhaoxin CPU. Disabling this option on other types of CPUs
507 makes the kernel a tiny bit smaller. Disabling it on a Zhaoxin
508 CPU might render the kernel unbootable.
509
510 If unsure, say N.