2 # CPU Frequency scaling
5 menu "CPU Frequency scaling"
7 source "drivers/cpufreq/Kconfig"
11 comment "CPUFreq processor drivers"
13 config X86_ACPI_CPUFREQ
14 tristate "ACPI Processor P-States driver"
16 depends on ACPI_PROCESSOR
18 This driver adds a CPUFreq driver which utilizes the ACPI
19 Processor Performance States.
20 This driver also supports Intel Enhanced Speedstep.
22 For details, take a look at <file:Documentation/cpu-freq/>.
27 tristate "AMD Elan SC400 and SC410"
31 This adds the CPUFreq driver for AMD Elan SC400 and SC410
34 You need to specify the processor maximum speed as boot
35 parameter: elanfreq=maxspeed (in kHz) or as module
38 For details, take a look at <file:Documentation/cpu-freq/>.
43 tristate "AMD Elan SC520"
47 This adds the CPUFreq driver for AMD Elan SC520 processor.
49 For details, take a look at <file:Documentation/cpu-freq/>.
54 config X86_POWERNOW_K6
55 tristate "AMD Mobile K6-2/K6-3 PowerNow!"
58 This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
61 For details, take a look at <file:Documentation/cpu-freq/>.
65 config X86_POWERNOW_K7
66 tristate "AMD Mobile Athlon/Duron PowerNow!"
69 This adds the CPUFreq driver for mobile AMD K7 mobile processors.
71 For details, take a look at <file:Documentation/cpu-freq/>.
75 config X86_POWERNOW_K7_ACPI
77 depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
78 depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
81 config X86_POWERNOW_K8
82 tristate "AMD Opteron/Athlon64 PowerNow!"
84 depends on EXPERIMENTAL
86 This adds the CPUFreq driver for mobile AMD Opteron/Athlon64 processors.
88 For details, take a look at <file:Documentation/cpu-freq/>.
92 config X86_POWERNOW_K8_ACPI
95 depends on X86_POWERNOW_K8
98 This provides access to the K8s Processor Performance States via ACPI.
99 This driver is probably required for CPUFreq to work with multi-socket and
100 SMP systems. It is not required on at least some single-socket yet
101 multi-core systems, even if SMP is enabled.
103 It is safe to say Y here.
105 config X86_GX_SUSPMOD
106 tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
109 This add the CPUFreq driver for NatSemi Geode processors which
110 support suspend modulation.
112 For details, take a look at <file:Documentation/cpu-freq/>.
116 config X86_SPEEDSTEP_CENTRINO
117 tristate "Intel Enhanced SpeedStep"
118 select CPU_FREQ_TABLE
119 select X86_SPEEDSTEP_CENTRINO_TABLE if (!X86_SPEEDSTEP_CENTRINO_ACPI)
121 This adds the CPUFreq driver for Enhanced SpeedStep enabled
122 mobile CPUs. This means Intel Pentium M (Centrino) CPUs. However,
123 you also need to say Y to "Use ACPI tables to decode..." below
124 [which might imply enabling ACPI] if you want to use this driver
127 For details, take a look at <file:Documentation/cpu-freq/>.
131 config X86_SPEEDSTEP_CENTRINO_ACPI
132 bool "Use ACPI tables to decode valid frequency/voltage (deprecated)"
133 depends on X86_SPEEDSTEP_CENTRINO && ACPI_PROCESSOR
134 depends on !(X86_SPEEDSTEP_CENTRINO = y && ACPI_PROCESSOR = m)
136 This is deprecated and this functionality is now merged into
137 acpi_cpufreq (X86_ACPI_CPUFREQ). Use that driver instead of
139 Use primarily the information provided in the BIOS ACPI tables
140 to determine valid CPU frequency and voltage pairings. It is
141 required for the driver to work on non-Banias CPUs.
145 config X86_SPEEDSTEP_CENTRINO_TABLE
146 bool "Built-in tables for Banias CPUs"
147 depends on X86_SPEEDSTEP_CENTRINO
150 Use built-in tables for Banias CPUs if ACPI encoding
155 config X86_SPEEDSTEP_ICH
156 tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
157 select CPU_FREQ_TABLE
159 This adds the CPUFreq driver for certain mobile Intel Pentium III
160 (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
161 mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
162 ICH3 or ICH4 southbridge.
164 For details, take a look at <file:Documentation/cpu-freq/>.
168 config X86_SPEEDSTEP_SMI
169 tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
170 select CPU_FREQ_TABLE
171 depends on EXPERIMENTAL
173 This adds the CPUFreq driver for certain mobile Intel Pentium III
174 (Coppermine), all mobile Intel Pentium III-M (Tualatin)
175 on systems which have an Intel 440BX/ZX/MX southbridge.
177 For details, take a look at <file:Documentation/cpu-freq/>.
181 config X86_P4_CLOCKMOD
182 tristate "Intel Pentium 4 clock modulation"
183 select CPU_FREQ_TABLE
185 This adds the CPUFreq driver for Intel Pentium 4 / XEON
188 For details, take a look at <file:Documentation/cpu-freq/>.
192 config X86_CPUFREQ_NFORCE2
193 tristate "nVidia nForce2 FSB changing"
194 depends on EXPERIMENTAL
196 This adds the CPUFreq driver for FSB changing on nVidia nForce2
199 For details, take a look at <file:Documentation/cpu-freq/>.
204 tristate "Transmeta LongRun"
206 This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
207 which support LongRun.
209 For details, take a look at <file:Documentation/cpu-freq/>.
214 tristate "VIA Cyrix III Longhaul"
215 select CPU_FREQ_TABLE
216 depends on ACPI_PROCESSOR
218 This adds the CPUFreq driver for VIA Samuel/CyrixIII,
219 VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
222 For details, take a look at <file:Documentation/cpu-freq/>.
226 config X86_E_POWERSAVER
227 tristate "VIA C7 Enhanced PowerSaver (EXPERIMENTAL)"
228 select CPU_FREQ_TABLE
229 depends on EXPERIMENTAL
231 This adds the CPUFreq driver for VIA C7 processors.
235 comment "shared options"
237 config X86_ACPI_CPUFREQ_PROC_INTF
238 bool "/proc/acpi/processor/../performance interface (deprecated)"
240 depends on X86_ACPI_CPUFREQ || X86_SPEEDSTEP_CENTRINO_ACPI || X86_POWERNOW_K7_ACPI || X86_POWERNOW_K8_ACPI
242 This enables the deprecated /proc/acpi/processor/../performance
243 interface. While it is helpful for debugging, the generic,
244 cross-architecture cpufreq interfaces should be used.
248 config X86_SPEEDSTEP_LIB
250 default X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD
252 config X86_SPEEDSTEP_RELAXED_CAP_CHECK
253 bool "Relaxed speedstep capability checks"
254 depends on (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
256 Don't perform all checks for a speedstep capable system which would
257 normally be done. Some ancient or strange systems, though speedstep
258 capable, don't always indicate that they are speedstep capable. This
259 option lets the probing code bypass some of those checks if the
260 parameter "relaxed_check=1" is passed to the module.