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.
21 For details, take a look at <file:Documentation/cpu-freq/>.
26 tristate "AMD Elan SC400 and SC410"
30 This adds the CPUFreq driver for AMD Elan SC400 and SC410
33 You need to specify the processor maximum speed as boot
34 parameter: elanfreq=maxspeed (in kHz) or as module
37 For details, take a look at <file:Documentation/cpu-freq/>.
42 tristate "AMD Elan SC520"
46 This adds the CPUFreq driver for AMD Elan SC520 processor.
48 For details, take a look at <file:Documentation/cpu-freq/>.
53 config X86_POWERNOW_K6
54 tristate "AMD Mobile K6-2/K6-3 PowerNow!"
57 This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
60 For details, take a look at <file:Documentation/cpu-freq/>.
64 config X86_POWERNOW_K7
65 tristate "AMD Mobile Athlon/Duron PowerNow!"
68 This adds the CPUFreq driver for mobile AMD K7 mobile processors.
70 For details, take a look at <file:Documentation/cpu-freq/>.
74 config X86_POWERNOW_K7_ACPI
76 depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
77 depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
80 config X86_POWERNOW_K8
81 tristate "AMD Opteron/Athlon64 PowerNow!"
83 depends on EXPERIMENTAL
85 This adds the CPUFreq driver for mobile AMD Opteron/Athlon64 processors.
87 For details, take a look at <file:Documentation/cpu-freq/>.
91 config X86_POWERNOW_K8_ACPI
93 depends on X86_POWERNOW_K8 && ACPI_PROCESSOR
94 depends on !(X86_POWERNOW_K8 = y && ACPI_PROCESSOR = m)
98 tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
101 This add the CPUFreq driver for NatSemi Geode processors which
102 support suspend modulation.
104 For details, take a look at <file:Documentation/cpu-freq/>.
108 config X86_SPEEDSTEP_CENTRINO
109 tristate "Intel Enhanced SpeedStep"
110 select CPU_FREQ_TABLE
111 select X86_SPEEDSTEP_CENTRINO_TABLE if (!X86_SPEEDSTEP_CENTRINO_ACPI)
113 This adds the CPUFreq driver for Enhanced SpeedStep enabled
114 mobile CPUs. This means Intel Pentium M (Centrino) CPUs. However,
115 you also need to say Y to "Use ACPI tables to decode..." below
116 [which might imply enabling ACPI] if you want to use this driver
119 For details, take a look at <file:Documentation/cpu-freq/>.
123 config X86_SPEEDSTEP_CENTRINO_ACPI
124 bool "Use ACPI tables to decode valid frequency/voltage pairs"
125 depends on X86_SPEEDSTEP_CENTRINO && ACPI_PROCESSOR
126 depends on !(X86_SPEEDSTEP_CENTRINO = y && ACPI_PROCESSOR = m)
129 Use primarily the information provided in the BIOS ACPI tables
130 to determine valid CPU frequency and voltage pairings. It is
131 required for the driver to work on non-Banias CPUs.
135 config X86_SPEEDSTEP_CENTRINO_TABLE
136 bool "Built-in tables for Banias CPUs"
137 depends on X86_SPEEDSTEP_CENTRINO
140 Use built-in tables for Banias CPUs if ACPI encoding
145 config X86_SPEEDSTEP_ICH
146 tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
147 select CPU_FREQ_TABLE
149 This adds the CPUFreq driver for certain mobile Intel Pentium III
150 (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
151 mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
152 ICH3 or ICH4 southbridge.
154 For details, take a look at <file:Documentation/cpu-freq/>.
158 config X86_SPEEDSTEP_SMI
159 tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
160 select CPU_FREQ_TABLE
161 depends on EXPERIMENTAL
163 This adds the CPUFreq driver for certain mobile Intel Pentium III
164 (Coppermine), all mobile Intel Pentium III-M (Tualatin)
165 on systems which have an Intel 440BX/ZX/MX southbridge.
167 For details, take a look at <file:Documentation/cpu-freq/>.
171 config X86_P4_CLOCKMOD
172 tristate "Intel Pentium 4 clock modulation"
173 select CPU_FREQ_TABLE
175 This adds the CPUFreq driver for Intel Pentium 4 / XEON
178 For details, take a look at <file:Documentation/cpu-freq/>.
182 config X86_CPUFREQ_NFORCE2
183 tristate "nVidia nForce2 FSB changing"
184 depends on EXPERIMENTAL
186 This adds the CPUFreq driver for FSB changing on nVidia nForce2
189 For details, take a look at <file:Documentation/cpu-freq/>.
194 tristate "Transmeta LongRun"
196 This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
197 which support LongRun.
199 For details, take a look at <file:Documentation/cpu-freq/>.
204 tristate "VIA Cyrix III Longhaul"
205 select CPU_FREQ_TABLE
206 depends on ACPI_PROCESSOR
208 This adds the CPUFreq driver for VIA Samuel/CyrixIII,
209 VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
212 For details, take a look at <file:Documentation/cpu-freq/>.
216 comment "shared options"
218 config X86_ACPI_CPUFREQ_PROC_INTF
219 bool "/proc/acpi/processor/../performance interface (deprecated)"
221 depends on X86_ACPI_CPUFREQ || X86_SPEEDSTEP_CENTRINO_ACPI || X86_POWERNOW_K7_ACPI || X86_POWERNOW_K8_ACPI
223 This enables the deprecated /proc/acpi/processor/../performance
224 interface. While it is helpful for debugging, the generic,
225 cross-architecture cpufreq interfaces should be used.
229 config X86_SPEEDSTEP_LIB
231 default X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD
233 config X86_SPEEDSTEP_RELAXED_CAP_CHECK
234 bool "Relaxed speedstep capability checks"
235 depends on (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
237 Don't perform all checks for a speedstep capable system which would
238 normally be done. Some ancient or strange systems, though speedstep
239 capable, don't always indicate that they are speedstep capable. This
240 option lets the probing code bypass some of those checks if the
241 parameter "relaxed_check=1" is passed to the module.