1 # Put here option for CPU selection and depending optimization
5 prompt "Processor family"
7 default GENERIC_CPU if X86_64
11 depends on X86_32 && !UML
13 This is the processor type of your CPU. This information is used for
14 optimizing purposes. In order to compile a kernel that can run on
15 all x86 CPU types (albeit not optimally fast), you can specify
18 The kernel will not necessarily run on earlier architectures than
19 the one you have chosen, e.g. a Pentium optimized kernel will run on
20 a PPro, but not necessarily on a i486.
22 Here are the settings recommended for greatest speed:
23 - "386" for the AMD/Cyrix/Intel 386DX/DXL/SL/SLC/SX, Cyrix/TI
24 486DLC/DLC2, and UMC 486SX-S. Only "386" kernels will run on a 386
26 - "486" for the AMD/Cyrix/IBM/Intel 486DX/DX2/DX4 or
27 SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or U5S.
28 - "586" for generic Pentium CPUs lacking the TSC
29 (time stamp counter) register.
30 - "Pentium-Classic" for the Intel Pentium.
31 - "Pentium-MMX" for the Intel Pentium MMX.
32 - "Pentium-Pro" for the Intel Pentium Pro.
33 - "Pentium-II" for the Intel Pentium II or pre-Coppermine Celeron.
34 - "Pentium-III" for the Intel Pentium III or Coppermine Celeron.
35 - "Pentium-4" for the Intel Pentium 4 or P4-based Celeron.
36 - "K6" for the AMD K6, K6-II and K6-III (aka K6-3D).
37 - "Athlon" for the AMD K7 family (Athlon/Duron/Thunderbird).
38 - "Crusoe" for the Transmeta Crusoe series.
39 - "Efficeon" for the Transmeta Efficeon series.
40 - "Winchip-C6" for original IDT Winchip.
41 - "Winchip-2" for IDT Winchips with 3dNow! capabilities.
42 - "GeodeGX1" for Geode GX1 (Cyrix MediaGX).
43 - "Geode GX/LX" For AMD Geode GX and LX processors.
44 - "CyrixIII/VIA C3" for VIA Cyrix III or VIA C3.
45 - "VIA C3-2" for VIA C3-2 "Nehemiah" (model 9 and above).
46 - "VIA C7" for VIA C7.
48 If you don't know what to do, choose "386".
54 Select this for a 486 series processor, either Intel or one of the
55 compatible processors from AMD, Cyrix, IBM, or Intel. Includes DX,
56 DX2, and DX4 variants; also SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or
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 a Geode GX1 (Cyrix MediaGX) chip.
216 Select this for AMD Geode GX and LX processors.
219 bool "CyrixIII/VIA-C3"
222 Select this for a Cyrix III or C3 chip. Presently Linux and GCC
223 treat this chip as a generic 586. Whilst the CPU is 686 class,
224 it lacks the cmov extension which gcc assumes is present when
226 Note that Nehemiah (Model 9) and above will not boot with this
227 kernel due to them lacking the 3DNow! instructions used in earlier
228 incarnations of the CPU.
231 bool "VIA C3-2 (Nehemiah)"
234 Select this for a VIA C3 "Nehemiah". Selecting this enables usage
235 of SSE and tells gcc to treat the CPU as a 686.
236 Note, this kernel will not boot on older (pre model 9) C3s.
242 Select this for a VIA C7. Selecting this uses the correct cache
243 shift and tells gcc to treat the CPU as a 686.
246 bool "Intel P4 / older Netburst based Xeon"
249 Optimize for Intel Pentium 4, Pentium D and older Nocona/Dempsey
250 Xeon CPUs with Intel 64bit which is compatible with x86-64.
251 Note that the latest Xeons (Xeon 51xx and 53xx) are not based on the
252 Netburst core and shouldn't use this option. You can distinguish them
253 using the cpu family field
254 in /proc/cpuinfo. Family 15 is an older Xeon, Family 6 a newer one.
257 bool "Core 2/newer Xeon"
260 Select this for Intel Core 2 and newer Core 2 Xeons (Xeon 51xx and
261 53xx) CPUs. You can distinguish newer from older Xeons by the CPU
262 family in /proc/cpuinfo. Newer ones have 6 and older ones 15
269 Select this for the Intel Atom platform. Intel Atom CPUs have an
270 in-order pipelining architecture and thus can benefit from
271 accordingly optimized code. Use a recent GCC with specific Atom
272 support in order to fully benefit from selecting this option.
275 bool "Generic-x86-64"
279 Run equally well on all x86-64 CPUs.
284 bool "Generic x86 support"
287 Instead of just including optimizations for the selected
288 x86 variant (e.g. PII, Crusoe or Athlon), include some more
289 generic optimizations as well. This will make the kernel
290 perform better on x86 CPUs other than that selected.
292 This is really intended for distributors who need more
293 generic optimizations.
299 select GENERIC_FIND_FIRST_BIT
300 select GENERIC_FIND_NEXT_BIT
303 # Define implied options from the CPU selection here
304 config X86_L1_CACHE_BYTES
306 default "128" if MPSC
307 default "64" if GENERIC_CPU || MK8 || MCORE2 || MATOM || X86_32
309 config X86_INTERNODE_CACHE_BYTES
311 default "4096" if X86_VSMP
312 default X86_L1_CACHE_BYTES if !X86_VSMP
315 def_bool X86_64 || (X86_32 && !M386)
317 config X86_L1_CACHE_SHIFT
319 default "7" if MPENTIUM4 || MPSC
320 default "4" if X86_ELAN || M486 || M386 || MGEODEGX1
321 default "5" if MWINCHIP3D || MWINCHIPC6 || MCRUSOE || MEFFICEON || MCYRIXIII || MK6 || MPENTIUMIII || MPENTIUMII || M686 || M586MMX || M586TSC || M586 || MVIAC3_2 || MGEODE_LX
322 default "6" if MK7 || MK8 || MPENTIUMM || MCORE2 || MATOM || MVIAC7 || X86_GENERIC || GENERIC_CPU
326 depends on X86_32 && !M386
328 config X86_PPRO_FENCE
329 bool "PentiumPro memory ordering errata workaround"
330 depends on M686 || M586MMX || M586TSC || M586 || M486 || M386 || MGEODEGX1
332 Old PentiumPro multiprocessor systems had errata that could cause
333 memory operations to violate the x86 ordering standard in rare cases.
334 Enabling this option will attempt to work around some (but not all)
335 occurances of this problem, at the cost of much heavier spinlock and
336 memory barrier operations.
338 If unsure, say n here. Even distro kernels should think twice before
339 enabling this: there are few systems, and an unlikely bug.
343 depends on M586MMX || M586TSC || M586 || M486 || M386
345 config X86_WP_WORKS_OK
351 depends on X86_32 && !M386
355 depends on X86_32 && !M386
359 depends on X86_32 && !M386
361 config X86_ALIGNMENT_16
363 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || X86_ELAN || MK6 || M586MMX || M586TSC || M586 || M486 || MVIAC3_2 || MGEODEGX1
365 config X86_INTEL_USERCOPY
367 depends on MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M586MMX || X86_GENERIC || MK8 || MK7 || MEFFICEON || MCORE2
369 config X86_USE_PPRO_CHECKSUM
371 depends on MWINCHIP3D || MWINCHIPC6 || MCYRIXIII || MK7 || MK6 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MK8 || MVIAC3_2 || MEFFICEON || MGEODE_LX || MCORE2 || MATOM
375 depends on (MCYRIXIII || MK7 || MGEODE_LX) && !UML
379 depends on (MWINCHIP3D || MWINCHIPC6) && MTRR
382 # P6_NOPs are a relatively minor optimization that require a family >=
383 # 6 processor, except that it is broken on certain VIA chips.
384 # Furthermore, AMD chips prefer a totally different sequence of NOPs
385 # (which work on all CPUs). In addition, it looks like Virtual PC
386 # does not understand them.
388 # As a result, disallow these if we're not compiling for X86_64 (these
389 # NOPs do work on all x86-64 capable chips); the list of processors in
390 # the right-hand clause are the cores that benefit from this optimization.
395 depends on (MCORE2 || MPENTIUM4 || MPSC)
399 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
403 depends on X86_PAE || X86_64
405 # this should be set for all -march=.. options where the compiler
409 depends on (MK8 || MK7 || MCORE2 || MPENTIUM4 || MPENTIUMM || MPENTIUMIII || MPENTIUMII || M686 || MVIAC3_2 || MVIAC7 || MCRUSOE || MEFFICEON || X86_64 || MATOM)
411 config X86_MINIMUM_CPU_FAMILY
413 default "64" if X86_64
414 default "6" if X86_32 && X86_P6_NOP
415 default "4" if X86_32 && (X86_XADD || X86_CMPXCHG || X86_BSWAP || X86_WP_WORKS_OK)
418 config X86_DEBUGCTLMSR
420 depends on !(MK6 || MWINCHIPC6 || MWINCHIP3D || MCYRIXIII || M586MMX || M586TSC || M586 || M486 || M386) && !UML
422 menuconfig PROCESSOR_SELECT
423 bool "Supported processor vendors" if EMBEDDED
425 This lets you choose what x86 vendor support code your kernel
430 bool "Support Intel processors" if PROCESSOR_SELECT
432 This enables detection, tunings and quirks for Intel processors
434 You need this enabled if you want your kernel to run on an
435 Intel CPU. Disabling this option on other types of CPUs
436 makes the kernel a tiny bit smaller. Disabling it on an Intel
437 CPU might render the kernel unbootable.
441 config CPU_SUP_CYRIX_32
443 bool "Support Cyrix processors" if PROCESSOR_SELECT
446 This enables detection, tunings and quirks for Cyrix processors
448 You need this enabled if you want your kernel to run on a
449 Cyrix CPU. Disabling this option on other types of CPUs
450 makes the kernel a tiny bit smaller. Disabling it on a Cyrix
451 CPU might render the kernel unbootable.
457 bool "Support AMD processors" if PROCESSOR_SELECT
459 This enables detection, tunings and quirks for AMD processors
461 You need this enabled if you want your kernel to run on an
462 AMD CPU. Disabling this option on other types of CPUs
463 makes the kernel a tiny bit smaller. Disabling it on an AMD
464 CPU might render the kernel unbootable.
468 config CPU_SUP_CENTAUR
470 bool "Support Centaur processors" if PROCESSOR_SELECT
472 This enables detection, tunings and quirks for Centaur processors
474 You need this enabled if you want your kernel to run on a
475 Centaur CPU. Disabling this option on other types of CPUs
476 makes the kernel a tiny bit smaller. Disabling it on a Centaur
477 CPU might render the kernel unbootable.
481 config CPU_SUP_TRANSMETA_32
483 bool "Support Transmeta processors" if PROCESSOR_SELECT
486 This enables detection, tunings and quirks for Transmeta processors
488 You need this enabled if you want your kernel to run on a
489 Transmeta CPU. Disabling this option on other types of CPUs
490 makes the kernel a tiny bit smaller. Disabling it on a Transmeta
491 CPU might render the kernel unbootable.
495 config CPU_SUP_UMC_32
497 bool "Support UMC processors" if PROCESSOR_SELECT
500 This enables detection, tunings and quirks for UMC processors
502 You need this enabled if you want your kernel to run on a
503 UMC CPU. Disabling this option on other types of CPUs
504 makes the kernel a tiny bit smaller. Disabling it on a UMC
505 CPU might render the kernel unbootable.
510 def_bool X86_PTRACE_BTS
511 depends on X86_DEBUGCTLMSR
512 select HAVE_HW_BRANCH_TRACER
514 config X86_PTRACE_BTS
515 bool "Branch Trace Store"
517 depends on X86_DEBUGCTLMSR
520 This adds a ptrace interface to the hardware's branch trace store.
522 Debuggers may use it to collect an execution trace of the debugged
523 application in order to answer the question 'how did I get here?'.
524 Debuggers may trace user mode as well as kernel mode.
526 Say Y unless there is no application development on this machine
527 and you want to save a small amount of code size.