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"
100 This add the CPUFreq driver for NatSemi Geode processors which
101 support suspend modulation.
103 For details, take a look at <file:Documentation/cpu-freq/>.
107 config X86_SPEEDSTEP_CENTRINO
108 tristate "Intel Enhanced SpeedStep"
109 select CPU_FREQ_TABLE
110 select X86_SPEEDSTEP_CENTRINO_TABLE if (!X86_SPEEDSTEP_CENTRINO_ACPI)
112 This adds the CPUFreq driver for Enhanced SpeedStep enabled
113 mobile CPUs. This means Intel Pentium M (Centrino) CPUs. However,
114 you also need to say Y to "Use ACPI tables to decode..." below
115 [which might imply enabling ACPI] if you want to use this driver
118 For details, take a look at <file:Documentation/cpu-freq/>.
122 config X86_SPEEDSTEP_CENTRINO_ACPI
123 bool "Use ACPI tables to decode valid frequency/voltage pairs"
124 depends on X86_SPEEDSTEP_CENTRINO && ACPI_PROCESSOR
125 depends on !(X86_SPEEDSTEP_CENTRINO = y && ACPI_PROCESSOR = m)
128 Use primarily the information provided in the BIOS ACPI tables
129 to determine valid CPU frequency and voltage pairings. It is
130 required for the driver to work on non-Banias CPUs.
134 config X86_SPEEDSTEP_CENTRINO_TABLE
135 bool "Built-in tables for Banias CPUs"
136 depends on X86_SPEEDSTEP_CENTRINO
139 Use built-in tables for Banias CPUs if ACPI encoding
144 config X86_SPEEDSTEP_ICH
145 tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
146 select CPU_FREQ_TABLE
148 This adds the CPUFreq driver for certain mobile Intel Pentium III
149 (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
150 mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
151 ICH3 or ICH4 southbridge.
153 For details, take a look at <file:Documentation/cpu-freq/>.
157 config X86_SPEEDSTEP_SMI
158 tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
159 select CPU_FREQ_TABLE
160 depends on EXPERIMENTAL
162 This adds the CPUFreq driver for certain mobile Intel Pentium III
163 (Coppermine), all mobile Intel Pentium III-M (Tualatin)
164 on systems which have an Intel 440BX/ZX/MX southbridge.
166 For details, take a look at <file:Documentation/cpu-freq/>.
170 config X86_P4_CLOCKMOD
171 tristate "Intel Pentium 4 clock modulation"
172 select CPU_FREQ_TABLE
174 This adds the CPUFreq driver for Intel Pentium 4 / XEON
177 For details, take a look at <file:Documentation/cpu-freq/>.
181 config X86_CPUFREQ_NFORCE2
182 tristate "nVidia nForce2 FSB changing"
183 depends on EXPERIMENTAL
185 This adds the CPUFreq driver for FSB changing on nVidia nForce2
188 For details, take a look at <file:Documentation/cpu-freq/>.
193 tristate "Transmeta LongRun"
195 This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
196 which support LongRun.
198 For details, take a look at <file:Documentation/cpu-freq/>.
203 tristate "VIA Cyrix III Longhaul"
204 select CPU_FREQ_TABLE
206 This adds the CPUFreq driver for VIA Samuel/CyrixIII,
207 VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
210 For details, take a look at <file:Documentation/cpu-freq/>.
214 comment "shared options"
216 config X86_ACPI_CPUFREQ_PROC_INTF
217 bool "/proc/acpi/processor/../performance interface (deprecated)"
219 depends on X86_ACPI_CPUFREQ || X86_SPEEDSTEP_CENTRINO_ACPI || X86_POWERNOW_K7_ACPI || X86_POWERNOW_K8_ACPI
221 This enables the deprecated /proc/acpi/processor/../performance
222 interface. While it is helpful for debugging, the generic,
223 cross-architecture cpufreq interfaces should be used.
227 config X86_SPEEDSTEP_LIB
229 default X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD
231 config X86_SPEEDSTEP_RELAXED_CAP_CHECK
232 bool "Relaxed speedstep capability checks"
233 depends on (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
235 Don't perform all checks for a speedstep capable system which would
236 normally be done. Some ancient or strange systems, though speedstep
237 capable, don't always indicate that they are speedstep capable. This
238 option lets the probing code bypass some of those checks if the
239 parameter "relaxed_check=1" is passed to the module.