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 ACPI && 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
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_TABLE
132 bool "Built-in tables for Banias CPUs"
133 depends on X86_SPEEDSTEP_CENTRINO
136 Use built-in tables for Banias CPUs if ACPI encoding
141 config X86_SPEEDSTEP_ICH
142 tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
143 select CPU_FREQ_TABLE
145 This adds the CPUFreq driver for certain mobile Intel Pentium III
146 (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
147 mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
148 ICH3 or ICH4 southbridge.
150 For details, take a look at <file:Documentation/cpu-freq/>.
154 config X86_SPEEDSTEP_SMI
155 tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
156 select CPU_FREQ_TABLE
157 depends on EXPERIMENTAL
159 This adds the CPUFreq driver for certain mobile Intel Pentium III
160 (Coppermine), all mobile Intel Pentium III-M (Tualatin)
161 on systems which have an Intel 440BX/ZX/MX southbridge.
163 For details, take a look at <file:Documentation/cpu-freq/>.
167 config X86_P4_CLOCKMOD
168 tristate "Intel Pentium 4 clock modulation"
169 select CPU_FREQ_TABLE
171 This adds the CPUFreq driver for Intel Pentium 4 / XEON
174 For details, take a look at <file:Documentation/cpu-freq/>.
178 config X86_CPUFREQ_NFORCE2
179 tristate "nVidia nForce2 FSB changing"
180 depends on EXPERIMENTAL
182 This adds the CPUFreq driver for FSB changing on nVidia nForce2
185 For details, take a look at <file:Documentation/cpu-freq/>.
190 tristate "Transmeta LongRun"
192 This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
193 which support LongRun.
195 For details, take a look at <file:Documentation/cpu-freq/>.
200 tristate "VIA Cyrix III Longhaul"
201 select CPU_FREQ_TABLE
202 depends on ACPI_PROCESSOR
204 This adds the CPUFreq driver for VIA Samuel/CyrixIII,
205 VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
208 For details, take a look at <file:Documentation/cpu-freq/>.
212 config X86_E_POWERSAVER
213 tristate "VIA C7 Enhanced PowerSaver (EXPERIMENTAL)"
214 select CPU_FREQ_TABLE
215 depends on EXPERIMENTAL
217 This adds the CPUFreq driver for VIA C7 processors.
221 comment "shared options"
223 config X86_ACPI_CPUFREQ_PROC_INTF
224 bool "/proc/acpi/processor/../performance interface (deprecated)"
226 depends on X86_ACPI_CPUFREQ || X86_POWERNOW_K7_ACPI || X86_POWERNOW_K8_ACPI
228 This enables the deprecated /proc/acpi/processor/../performance
229 interface. While it is helpful for debugging, the generic,
230 cross-architecture cpufreq interfaces should be used.
234 config X86_SPEEDSTEP_LIB
236 default X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD
238 config X86_SPEEDSTEP_RELAXED_CAP_CHECK
239 bool "Relaxed speedstep capability checks"
240 depends on (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
242 Don't perform all checks for a speedstep capable system which would
243 normally be done. Some ancient or strange systems, though speedstep
244 capable, don't always indicate that they are speedstep capable. This
245 option lets the probing code bypass some of those checks if the
246 parameter "relaxed_check=1" is passed to the module.