2 # x86 CPU Frequency scaling drivers
5 config X86_INTEL_PSTATE
6 bool "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.
18 config X86_PCC_CPUFREQ
19 tristate "Processor Clocking Control interface driver"
20 depends on ACPI && ACPI_PROCESSOR
22 This driver adds support for the PCC interface.
24 For details, take a look at:
25 <file:Documentation/cpu-freq/pcc-cpufreq.txt>.
27 To compile this driver as a module, choose M here: the
28 module will be called pcc-cpufreq.
32 config X86_ACPI_CPUFREQ
33 tristate "ACPI Processor P-States driver"
35 depends on ACPI_PROCESSOR
37 This driver adds a CPUFreq driver which utilizes the ACPI
38 Processor Performance States.
39 This driver also supports Intel Enhanced Speedstep and newer
42 To compile this driver as a module, choose M here: the
43 module will be called acpi-cpufreq.
45 For details, take a look at <file:Documentation/cpu-freq/>.
49 config X86_ACPI_CPUFREQ_CPB
51 bool "Legacy cpb sysfs knob support for AMD CPUs"
52 depends on X86_ACPI_CPUFREQ && CPU_SUP_AMD
54 The powernow-k8 driver used to provide a sysfs knob called "cpb"
55 to disable the Core Performance Boosting feature of AMD CPUs. This
56 file has now been superseeded by the more generic "boost" entry.
58 By enabling this option the acpi_cpufreq driver provides the old
59 entry in addition to the new boost ones, for compatibility reasons.
62 tristate "AMD Elan SC400 and SC410"
66 This adds the CPUFreq driver for AMD Elan SC400 and SC410
69 You need to specify the processor maximum speed as boot
70 parameter: elanfreq=maxspeed (in kHz) or as module
73 For details, take a look at <file:Documentation/cpu-freq/>.
78 tristate "AMD Elan SC520"
82 This adds the CPUFreq driver for AMD Elan SC520 processor.
84 For details, take a look at <file:Documentation/cpu-freq/>.
89 config X86_POWERNOW_K6
90 tristate "AMD Mobile K6-2/K6-3 PowerNow!"
94 This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
97 For details, take a look at <file:Documentation/cpu-freq/>.
101 config X86_POWERNOW_K7
102 tristate "AMD Mobile Athlon/Duron PowerNow!"
103 select CPU_FREQ_TABLE
106 This adds the CPUFreq driver for mobile AMD K7 mobile processors.
108 For details, take a look at <file:Documentation/cpu-freq/>.
112 config X86_POWERNOW_K7_ACPI
114 depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
115 depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
119 config X86_POWERNOW_K8
120 tristate "AMD Opteron/Athlon64 PowerNow!"
121 select CPU_FREQ_TABLE
122 depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
124 This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
125 Support for K10 and newer processors is now in acpi-cpufreq.
127 To compile this driver as a module, choose M here: the
128 module will be called powernow-k8.
130 For details, take a look at <file:Documentation/cpu-freq/>.
132 config X86_GX_SUSPMOD
133 tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
134 depends on X86_32 && PCI
136 This add the CPUFreq driver for NatSemi Geode processors which
137 support suspend modulation.
139 For details, take a look at <file:Documentation/cpu-freq/>.
143 config X86_SPEEDSTEP_CENTRINO
144 tristate "Intel Enhanced SpeedStep (deprecated)"
145 select CPU_FREQ_TABLE
146 select X86_SPEEDSTEP_CENTRINO_TABLE if X86_32
147 depends on X86_32 || (X86_64 && ACPI_PROCESSOR)
149 This is deprecated and this functionality is now merged into
150 acpi_cpufreq (X86_ACPI_CPUFREQ). Use that driver instead of
152 This adds the CPUFreq driver for Enhanced SpeedStep enabled
153 mobile CPUs. This means Intel Pentium M (Centrino) CPUs
154 or 64bit enabled Intel Xeons.
156 To compile this driver as a module, choose M here: the
157 module will be called speedstep-centrino.
159 For details, take a look at <file:Documentation/cpu-freq/>.
163 config X86_SPEEDSTEP_CENTRINO_TABLE
164 bool "Built-in tables for Banias CPUs"
165 depends on X86_32 && X86_SPEEDSTEP_CENTRINO
168 Use built-in tables for Banias CPUs if ACPI encoding
173 config X86_SPEEDSTEP_ICH
174 tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
175 select CPU_FREQ_TABLE
178 This adds the CPUFreq driver for certain mobile Intel Pentium III
179 (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
180 mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
181 ICH3 or ICH4 southbridge.
183 For details, take a look at <file:Documentation/cpu-freq/>.
187 config X86_SPEEDSTEP_SMI
188 tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
189 select CPU_FREQ_TABLE
190 depends on X86_32 && EXPERIMENTAL
192 This adds the CPUFreq driver for certain mobile Intel Pentium III
193 (Coppermine), all mobile Intel Pentium III-M (Tualatin)
194 on systems which have an Intel 440BX/ZX/MX southbridge.
196 For details, take a look at <file:Documentation/cpu-freq/>.
200 config X86_P4_CLOCKMOD
201 tristate "Intel Pentium 4 clock modulation"
202 select CPU_FREQ_TABLE
204 This adds the CPUFreq driver for Intel Pentium 4 / XEON
205 processors. When enabled it will lower CPU temperature by skipping
208 This driver should be only used in exceptional
209 circumstances when very low power is needed because it causes severe
210 slowdowns and noticeable latencies. Normally Speedstep should be used
213 To compile this driver as a module, choose M here: the
214 module will be called p4-clockmod.
216 For details, take a look at <file:Documentation/cpu-freq/>.
218 Unless you are absolutely sure say N.
220 config X86_CPUFREQ_NFORCE2
221 tristate "nVidia nForce2 FSB changing"
222 depends on X86_32 && EXPERIMENTAL
224 This adds the CPUFreq driver for FSB changing on nVidia nForce2
227 For details, take a look at <file:Documentation/cpu-freq/>.
232 tristate "Transmeta LongRun"
235 This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
236 which support LongRun.
238 For details, take a look at <file:Documentation/cpu-freq/>.
243 tristate "VIA Cyrix III Longhaul"
244 select CPU_FREQ_TABLE
245 depends on X86_32 && ACPI_PROCESSOR
247 This adds the CPUFreq driver for VIA Samuel/CyrixIII,
248 VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
251 For details, take a look at <file:Documentation/cpu-freq/>.
255 config X86_E_POWERSAVER
256 tristate "VIA C7 Enhanced PowerSaver (DANGEROUS)"
257 select CPU_FREQ_TABLE
258 depends on X86_32 && EXPERIMENTAL
260 This adds the CPUFreq driver for VIA C7 processors. However, this driver
261 does not have any safeguards to prevent operating the CPU out of spec
262 and is thus considered dangerous. Please use the regular ACPI cpufreq
263 driver, enabled by CONFIG_X86_ACPI_CPUFREQ.
267 comment "shared options"
269 config X86_SPEEDSTEP_LIB
271 default (X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD)
273 config X86_SPEEDSTEP_RELAXED_CAP_CHECK
274 bool "Relaxed speedstep capability checks"
275 depends on X86_32 && (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
277 Don't perform all checks for a speedstep capable system which would
278 normally be done. Some ancient or strange systems, though speedstep
279 capable, don't always indicate that they are speedstep capable. This
280 option lets the probing code bypass some of those checks if the
281 parameter "relaxed_check=1" is passed to the module.