2 # x86 CPU Frequency scaling drivers
5 config X86_INTEL_PSTATE
6 tristate "Intel P state control"
9 This driver provides a P state for Intel core processors.
10 The driver implements an internal governor and will become
11 the scaling driver and governor for Sandy bridge processors.
13 When this driver is enabled it will become the perferred
14 scaling driver for Sandy bridge processors.
16 Note: This driver should be built with the same settings as
17 the other scaling drivers configured into the system
18 (module/built-in) in order for the driver to register itself
19 as the scaling driver on the system.
23 config X86_PCC_CPUFREQ
24 tristate "Processor Clocking Control interface driver"
25 depends on ACPI && ACPI_PROCESSOR
27 This driver adds support for the PCC interface.
29 For details, take a look at:
30 <file:Documentation/cpu-freq/pcc-cpufreq.txt>.
32 To compile this driver as a module, choose M here: the
33 module will be called pcc-cpufreq.
37 config X86_ACPI_CPUFREQ
38 tristate "ACPI Processor P-States driver"
40 depends on ACPI_PROCESSOR
42 This driver adds a CPUFreq driver which utilizes the ACPI
43 Processor Performance States.
44 This driver also supports Intel Enhanced Speedstep and newer
47 To compile this driver as a module, choose M here: the
48 module will be called acpi-cpufreq.
50 For details, take a look at <file:Documentation/cpu-freq/>.
54 config X86_ACPI_CPUFREQ_CPB
56 bool "Legacy cpb sysfs knob support for AMD CPUs"
57 depends on X86_ACPI_CPUFREQ && CPU_SUP_AMD
59 The powernow-k8 driver used to provide a sysfs knob called "cpb"
60 to disable the Core Performance Boosting feature of AMD CPUs. This
61 file has now been superseeded by the more generic "boost" entry.
63 By enabling this option the acpi_cpufreq driver provides the old
64 entry in addition to the new boost ones, for compatibility reasons.
67 tristate "AMD Elan SC400 and SC410"
71 This adds the CPUFreq driver for AMD Elan SC400 and SC410
74 You need to specify the processor maximum speed as boot
75 parameter: elanfreq=maxspeed (in kHz) or as module
78 For details, take a look at <file:Documentation/cpu-freq/>.
83 tristate "AMD Elan SC520"
87 This adds the CPUFreq driver for AMD Elan SC520 processor.
89 For details, take a look at <file:Documentation/cpu-freq/>.
94 config X86_POWERNOW_K6
95 tristate "AMD Mobile K6-2/K6-3 PowerNow!"
99 This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
100 AMD K6-3+ processors.
102 For details, take a look at <file:Documentation/cpu-freq/>.
106 config X86_POWERNOW_K7
107 tristate "AMD Mobile Athlon/Duron PowerNow!"
108 select CPU_FREQ_TABLE
111 This adds the CPUFreq driver for mobile AMD K7 mobile processors.
113 For details, take a look at <file:Documentation/cpu-freq/>.
117 config X86_POWERNOW_K7_ACPI
119 depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
120 depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
124 config X86_POWERNOW_K8
125 tristate "AMD Opteron/Athlon64 PowerNow!"
126 select CPU_FREQ_TABLE
127 depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
129 This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
130 Support for K10 and newer processors is now in acpi-cpufreq.
132 To compile this driver as a module, choose M here: the
133 module will be called powernow-k8.
135 For details, take a look at <file:Documentation/cpu-freq/>.
137 config X86_GX_SUSPMOD
138 tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
139 depends on X86_32 && PCI
141 This add the CPUFreq driver for NatSemi Geode processors which
142 support suspend modulation.
144 For details, take a look at <file:Documentation/cpu-freq/>.
148 config X86_SPEEDSTEP_CENTRINO
149 tristate "Intel Enhanced SpeedStep (deprecated)"
150 select CPU_FREQ_TABLE
151 select X86_SPEEDSTEP_CENTRINO_TABLE if X86_32
152 depends on X86_32 || (X86_64 && ACPI_PROCESSOR)
154 This is deprecated and this functionality is now merged into
155 acpi_cpufreq (X86_ACPI_CPUFREQ). Use that driver instead of
157 This adds the CPUFreq driver for Enhanced SpeedStep enabled
158 mobile CPUs. This means Intel Pentium M (Centrino) CPUs
159 or 64bit enabled Intel Xeons.
161 To compile this driver as a module, choose M here: the
162 module will be called speedstep-centrino.
164 For details, take a look at <file:Documentation/cpu-freq/>.
168 config X86_SPEEDSTEP_CENTRINO_TABLE
169 bool "Built-in tables for Banias CPUs"
170 depends on X86_32 && X86_SPEEDSTEP_CENTRINO
173 Use built-in tables for Banias CPUs if ACPI encoding
178 config X86_SPEEDSTEP_ICH
179 tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
180 select CPU_FREQ_TABLE
183 This adds the CPUFreq driver for certain mobile Intel Pentium III
184 (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
185 mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
186 ICH3 or ICH4 southbridge.
188 For details, take a look at <file:Documentation/cpu-freq/>.
192 config X86_SPEEDSTEP_SMI
193 tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
194 select CPU_FREQ_TABLE
195 depends on X86_32 && EXPERIMENTAL
197 This adds the CPUFreq driver for certain mobile Intel Pentium III
198 (Coppermine), all mobile Intel Pentium III-M (Tualatin)
199 on systems which have an Intel 440BX/ZX/MX southbridge.
201 For details, take a look at <file:Documentation/cpu-freq/>.
205 config X86_P4_CLOCKMOD
206 tristate "Intel Pentium 4 clock modulation"
207 select CPU_FREQ_TABLE
209 This adds the CPUFreq driver for Intel Pentium 4 / XEON
210 processors. When enabled it will lower CPU temperature by skipping
213 This driver should be only used in exceptional
214 circumstances when very low power is needed because it causes severe
215 slowdowns and noticeable latencies. Normally Speedstep should be used
218 To compile this driver as a module, choose M here: the
219 module will be called p4-clockmod.
221 For details, take a look at <file:Documentation/cpu-freq/>.
223 Unless you are absolutely sure say N.
225 config X86_CPUFREQ_NFORCE2
226 tristate "nVidia nForce2 FSB changing"
227 depends on X86_32 && EXPERIMENTAL
229 This adds the CPUFreq driver for FSB changing on nVidia nForce2
232 For details, take a look at <file:Documentation/cpu-freq/>.
237 tristate "Transmeta LongRun"
240 This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
241 which support LongRun.
243 For details, take a look at <file:Documentation/cpu-freq/>.
248 tristate "VIA Cyrix III Longhaul"
249 select CPU_FREQ_TABLE
250 depends on X86_32 && ACPI_PROCESSOR
252 This adds the CPUFreq driver for VIA Samuel/CyrixIII,
253 VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
256 For details, take a look at <file:Documentation/cpu-freq/>.
260 config X86_E_POWERSAVER
261 tristate "VIA C7 Enhanced PowerSaver (DANGEROUS)"
262 select CPU_FREQ_TABLE
263 depends on X86_32 && EXPERIMENTAL
265 This adds the CPUFreq driver for VIA C7 processors. However, this driver
266 does not have any safeguards to prevent operating the CPU out of spec
267 and is thus considered dangerous. Please use the regular ACPI cpufreq
268 driver, enabled by CONFIG_X86_ACPI_CPUFREQ.
272 comment "shared options"
274 config X86_SPEEDSTEP_LIB
276 default (X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD)
278 config X86_SPEEDSTEP_RELAXED_CAP_CHECK
279 bool "Relaxed speedstep capability checks"
280 depends on X86_32 && (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
282 Don't perform all checks for a speedstep capable system which would
283 normally be done. Some ancient or strange systems, though speedstep
284 capable, don't always indicate that they are speedstep capable. This
285 option lets the probing code bypass some of those checks if the
286 parameter "relaxed_check=1" is passed to the module.