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1menu "CPU Frequency scaling"
2
3config CPU_FREQ
4 bool "CPU Frequency scaling"
5 help
6 CPU Frequency scaling allows you to change the clock speed of
7 CPUs on the fly. This is a nice method to save power, because
8 the lower the CPU clock speed, the less power the CPU consumes.
9
10 Note that this driver doesn't automatically change the CPU
11 clock speed, you need to either enable a dynamic cpufreq governor
12 (see below) after boot, or use a userspace tool.
13
14 For details, take a look at <file:Documentation/cpu-freq>.
15
16 If in doubt, say N.
17
18if CPU_FREQ
19
20config CPU_FREQ_TABLE
21 tristate
22
23config CPU_FREQ_STAT
24 tristate "CPU frequency translation statistics"
25 select CPU_FREQ_TABLE
26 default y
27 help
28 This driver exports CPU frequency statistics information through sysfs
29 file system.
30
31 To compile this driver as a module, choose M here: the
32 module will be called cpufreq_stats.
33
34 If in doubt, say N.
35
36config CPU_FREQ_STAT_DETAILS
37 bool "CPU frequency translation statistics details"
38 depends on CPU_FREQ_STAT
39 help
40 This will show detail CPU frequency translation table in sysfs file
41 system.
42
43 If in doubt, say N.
44
45choice
46 prompt "Default CPUFreq governor"
47 default CPU_FREQ_DEFAULT_GOV_USERSPACE if CPU_FREQ_SA1100 || CPU_FREQ_SA1110
48 default CPU_FREQ_DEFAULT_GOV_PERFORMANCE
49 help
50 This option sets which CPUFreq governor shall be loaded at
51 startup. If in doubt, select 'performance'.
52
53config CPU_FREQ_DEFAULT_GOV_PERFORMANCE
54 bool "performance"
55 select CPU_FREQ_GOV_PERFORMANCE
56 help
57 Use the CPUFreq governor 'performance' as default. This sets
58 the frequency statically to the highest frequency supported by
59 the CPU.
60
61config CPU_FREQ_DEFAULT_GOV_POWERSAVE
62 bool "powersave"
63 depends on EXPERT
64 select CPU_FREQ_GOV_POWERSAVE
65 help
66 Use the CPUFreq governor 'powersave' as default. This sets
67 the frequency statically to the lowest frequency supported by
68 the CPU.
69
70config CPU_FREQ_DEFAULT_GOV_USERSPACE
71 bool "userspace"
72 select CPU_FREQ_GOV_USERSPACE
73 help
74 Use the CPUFreq governor 'userspace' as default. This allows
75 you to set the CPU frequency manually or when a userspace
76 program shall be able to set the CPU dynamically without having
77 to enable the userspace governor manually.
78
79config CPU_FREQ_DEFAULT_GOV_ONDEMAND
80 bool "ondemand"
81 select CPU_FREQ_GOV_ONDEMAND
82 select CPU_FREQ_GOV_PERFORMANCE
83 help
84 Use the CPUFreq governor 'ondemand' as default. This allows
85 you to get a full dynamic frequency capable system by simply
86 loading your cpufreq low-level hardware driver.
87 Be aware that not all cpufreq drivers support the ondemand
88 governor. If unsure have a look at the help section of the
89 driver. Fallback governor will be the performance governor.
90
91config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
92 bool "conservative"
93 select CPU_FREQ_GOV_CONSERVATIVE
94 select CPU_FREQ_GOV_PERFORMANCE
95 help
96 Use the CPUFreq governor 'conservative' as default. This allows
97 you to get a full dynamic frequency capable system by simply
98 loading your cpufreq low-level hardware driver.
99 Be aware that not all cpufreq drivers support the conservative
100 governor. If unsure have a look at the help section of the
101 driver. Fallback governor will be the performance governor.
102endchoice
103
104config CPU_FREQ_GOV_PERFORMANCE
105 tristate "'performance' governor"
106 help
107 This cpufreq governor sets the frequency statically to the
108 highest available CPU frequency.
109
110 To compile this driver as a module, choose M here: the
111 module will be called cpufreq_performance.
112
113 If in doubt, say Y.
114
115config CPU_FREQ_GOV_POWERSAVE
116 tristate "'powersave' governor"
117 help
118 This cpufreq governor sets the frequency statically to the
119 lowest available CPU frequency.
120
121 To compile this driver as a module, choose M here: the
122 module will be called cpufreq_powersave.
123
124 If in doubt, say Y.
125
126config CPU_FREQ_GOV_USERSPACE
127 tristate "'userspace' governor for userspace frequency scaling"
128 help
129 Enable this cpufreq governor when you either want to set the
130 CPU frequency manually or when a userspace program shall
131 be able to set the CPU dynamically, like on LART
132 <http://www.lartmaker.nl/>.
133
134 To compile this driver as a module, choose M here: the
135 module will be called cpufreq_userspace.
136
137 For details, take a look at <file:Documentation/cpu-freq/>.
138
139 If in doubt, say Y.
140
141config CPU_FREQ_GOV_ONDEMAND
142 tristate "'ondemand' cpufreq policy governor"
143 select CPU_FREQ_TABLE
144 help
145 'ondemand' - This driver adds a dynamic cpufreq policy governor.
146 The governor does a periodic polling and
147 changes frequency based on the CPU utilization.
148 The support for this governor depends on CPU capability to
149 do fast frequency switching (i.e, very low latency frequency
150 transitions).
151
152 To compile this driver as a module, choose M here: the
153 module will be called cpufreq_ondemand.
154
155 For details, take a look at linux/Documentation/cpu-freq.
156
157 If in doubt, say N.
158
159config CPU_FREQ_GOV_CONSERVATIVE
160 tristate "'conservative' cpufreq governor"
161 depends on CPU_FREQ
162 help
163 'conservative' - this driver is rather similar to the 'ondemand'
164 governor both in its source code and its purpose, the difference is
165 its optimisation for better suitability in a battery powered
166 environment. The frequency is gracefully increased and decreased
167 rather than jumping to 100% when speed is required.
168
169 If you have a desktop machine then you should really be considering
170 the 'ondemand' governor instead, however if you are using a laptop,
171 PDA or even an AMD64 based computer (due to the unacceptable
172 step-by-step latency issues between the minimum and maximum frequency
173 transitions in the CPU) you will probably want to use this governor.
174
175 To compile this driver as a module, choose M here: the
176 module will be called cpufreq_conservative.
177
178 For details, take a look at linux/Documentation/cpu-freq.
179
180 If in doubt, say N.
181
182menu "x86 CPU frequency scaling drivers"
183depends on X86
184source "drivers/cpufreq/Kconfig.x86"
185endmenu
186
187menu "ARM CPU frequency scaling drivers"
188depends on ARM
189source "drivers/cpufreq/Kconfig.arm"
190endmenu
191
192menu "PowerPC CPU frequency scaling drivers"
193depends on PPC32 || PPC64
194source "drivers/cpufreq/Kconfig.powerpc"
195endmenu
196
197endif
198endmenu
1menu "CPU Frequency scaling"
2
3config CPU_FREQ
4 bool "CPU Frequency scaling"
5 select SRCU
6 help
7 CPU Frequency scaling allows you to change the clock speed of
8 CPUs on the fly. This is a nice method to save power, because
9 the lower the CPU clock speed, the less power the CPU consumes.
10
11 Note that this driver doesn't automatically change the CPU
12 clock speed, you need to either enable a dynamic cpufreq governor
13 (see below) after boot, or use a userspace tool.
14
15 For details, take a look at <file:Documentation/cpu-freq>.
16
17 If in doubt, say N.
18
19if CPU_FREQ
20
21config CPU_FREQ_GOV_ATTR_SET
22 bool
23
24config CPU_FREQ_GOV_COMMON
25 select CPU_FREQ_GOV_ATTR_SET
26 select IRQ_WORK
27 bool
28
29config CPU_FREQ_BOOST_SW
30 bool
31 depends on THERMAL
32
33config CPU_FREQ_STAT
34 bool "CPU frequency transition statistics"
35 help
36 Export CPU frequency statistics information through sysfs.
37
38 If in doubt, say N.
39
40choice
41 prompt "Default CPUFreq governor"
42 default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1100_CPUFREQ || ARM_SA1110_CPUFREQ
43 default CPU_FREQ_DEFAULT_GOV_PERFORMANCE
44 help
45 This option sets which CPUFreq governor shall be loaded at
46 startup. If in doubt, select 'performance'.
47
48config CPU_FREQ_DEFAULT_GOV_PERFORMANCE
49 bool "performance"
50 select CPU_FREQ_GOV_PERFORMANCE
51 help
52 Use the CPUFreq governor 'performance' as default. This sets
53 the frequency statically to the highest frequency supported by
54 the CPU.
55
56config CPU_FREQ_DEFAULT_GOV_POWERSAVE
57 bool "powersave"
58 select CPU_FREQ_GOV_POWERSAVE
59 help
60 Use the CPUFreq governor 'powersave' as default. This sets
61 the frequency statically to the lowest frequency supported by
62 the CPU.
63
64config CPU_FREQ_DEFAULT_GOV_USERSPACE
65 bool "userspace"
66 select CPU_FREQ_GOV_USERSPACE
67 help
68 Use the CPUFreq governor 'userspace' as default. This allows
69 you to set the CPU frequency manually or when a userspace
70 program shall be able to set the CPU dynamically without having
71 to enable the userspace governor manually.
72
73config CPU_FREQ_DEFAULT_GOV_ONDEMAND
74 bool "ondemand"
75 select CPU_FREQ_GOV_ONDEMAND
76 select CPU_FREQ_GOV_PERFORMANCE
77 help
78 Use the CPUFreq governor 'ondemand' as default. This allows
79 you to get a full dynamic frequency capable system by simply
80 loading your cpufreq low-level hardware driver.
81 Be aware that not all cpufreq drivers support the ondemand
82 governor. If unsure have a look at the help section of the
83 driver. Fallback governor will be the performance governor.
84
85config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
86 bool "conservative"
87 select CPU_FREQ_GOV_CONSERVATIVE
88 select CPU_FREQ_GOV_PERFORMANCE
89 help
90 Use the CPUFreq governor 'conservative' as default. This allows
91 you to get a full dynamic frequency capable system by simply
92 loading your cpufreq low-level hardware driver.
93 Be aware that not all cpufreq drivers support the conservative
94 governor. If unsure have a look at the help section of the
95 driver. Fallback governor will be the performance governor.
96
97config CPU_FREQ_DEFAULT_GOV_SCHEDUTIL
98 bool "schedutil"
99 depends on SMP
100 select CPU_FREQ_GOV_SCHEDUTIL
101 select CPU_FREQ_GOV_PERFORMANCE
102 help
103 Use the 'schedutil' CPUFreq governor by default. If unsure,
104 have a look at the help section of that governor. The fallback
105 governor will be 'performance'.
106
107endchoice
108
109config CPU_FREQ_GOV_PERFORMANCE
110 tristate "'performance' governor"
111 help
112 This cpufreq governor sets the frequency statically to the
113 highest available CPU frequency.
114
115 To compile this driver as a module, choose M here: the
116 module will be called cpufreq_performance.
117
118 If in doubt, say Y.
119
120config CPU_FREQ_GOV_POWERSAVE
121 tristate "'powersave' governor"
122 help
123 This cpufreq governor sets the frequency statically to the
124 lowest available CPU frequency.
125
126 To compile this driver as a module, choose M here: the
127 module will be called cpufreq_powersave.
128
129 If in doubt, say Y.
130
131config CPU_FREQ_GOV_USERSPACE
132 tristate "'userspace' governor for userspace frequency scaling"
133 help
134 Enable this cpufreq governor when you either want to set the
135 CPU frequency manually or when a userspace program shall
136 be able to set the CPU dynamically, like on LART
137 <http://www.lartmaker.nl/>.
138
139 To compile this driver as a module, choose M here: the
140 module will be called cpufreq_userspace.
141
142 For details, take a look at <file:Documentation/cpu-freq/>.
143
144 If in doubt, say Y.
145
146config CPU_FREQ_GOV_ONDEMAND
147 tristate "'ondemand' cpufreq policy governor"
148 select CPU_FREQ_GOV_COMMON
149 help
150 'ondemand' - This driver adds a dynamic cpufreq policy governor.
151 The governor does a periodic polling and
152 changes frequency based on the CPU utilization.
153 The support for this governor depends on CPU capability to
154 do fast frequency switching (i.e, very low latency frequency
155 transitions).
156
157 To compile this driver as a module, choose M here: the
158 module will be called cpufreq_ondemand.
159
160 For details, take a look at linux/Documentation/cpu-freq.
161
162 If in doubt, say N.
163
164config CPU_FREQ_GOV_CONSERVATIVE
165 tristate "'conservative' cpufreq governor"
166 depends on CPU_FREQ
167 select CPU_FREQ_GOV_COMMON
168 help
169 'conservative' - this driver is rather similar to the 'ondemand'
170 governor both in its source code and its purpose, the difference is
171 its optimisation for better suitability in a battery powered
172 environment. The frequency is gracefully increased and decreased
173 rather than jumping to 100% when speed is required.
174
175 If you have a desktop machine then you should really be considering
176 the 'ondemand' governor instead, however if you are using a laptop,
177 PDA or even an AMD64 based computer (due to the unacceptable
178 step-by-step latency issues between the minimum and maximum frequency
179 transitions in the CPU) you will probably want to use this governor.
180
181 To compile this driver as a module, choose M here: the
182 module will be called cpufreq_conservative.
183
184 For details, take a look at linux/Documentation/cpu-freq.
185
186 If in doubt, say N.
187
188config CPU_FREQ_GOV_SCHEDUTIL
189 bool "'schedutil' cpufreq policy governor"
190 depends on CPU_FREQ && SMP
191 select CPU_FREQ_GOV_ATTR_SET
192 select IRQ_WORK
193 help
194 This governor makes decisions based on the utilization data provided
195 by the scheduler. It sets the CPU frequency to be proportional to
196 the utilization/capacity ratio coming from the scheduler. If the
197 utilization is frequency-invariant, the new frequency is also
198 proportional to the maximum available frequency. If that is not the
199 case, it is proportional to the current frequency of the CPU. The
200 frequency tipping point is at utilization/capacity equal to 80% in
201 both cases.
202
203 If in doubt, say N.
204
205comment "CPU frequency scaling drivers"
206
207config CPUFREQ_DT
208 tristate "Generic DT based cpufreq driver"
209 depends on HAVE_CLK && OF
210 # if CPU_THERMAL is on and THERMAL=m, CPUFREQ_DT cannot be =y:
211 depends on !CPU_THERMAL || THERMAL
212 select CPUFREQ_DT_PLATDEV
213 select PM_OPP
214 help
215 This adds a generic DT based cpufreq driver for frequency management.
216 It supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
217 systems.
218
219 If in doubt, say N.
220
221config CPUFREQ_DT_PLATDEV
222 bool
223 help
224 This adds a generic DT based cpufreq platdev driver for frequency
225 management. This creates a 'cpufreq-dt' platform device, on the
226 supported platforms.
227
228 If in doubt, say N.
229
230if X86
231source "drivers/cpufreq/Kconfig.x86"
232endif
233
234if ARM || ARM64
235source "drivers/cpufreq/Kconfig.arm"
236endif
237
238if PPC32 || PPC64
239source "drivers/cpufreq/Kconfig.powerpc"
240endif
241
242if IA64
243config IA64_ACPI_CPUFREQ
244 tristate "ACPI Processor P-States driver"
245 depends on ACPI_PROCESSOR
246 help
247 This driver adds a CPUFreq driver which utilizes the ACPI
248 Processor Performance States.
249
250 For details, take a look at <file:Documentation/cpu-freq/>.
251
252 If in doubt, say N.
253endif
254
255if MIPS
256config BMIPS_CPUFREQ
257 tristate "BMIPS CPUfreq Driver"
258 help
259 This option adds a CPUfreq driver for BMIPS processors with
260 support for configurable CPU frequency.
261
262 For now, BMIPS5 chips are supported (such as the Broadcom 7425).
263
264 If in doubt, say N.
265
266config LOONGSON2_CPUFREQ
267 tristate "Loongson2 CPUFreq Driver"
268 depends on LEMOTE_MACH2F
269 help
270 This option adds a CPUFreq driver for loongson processors which
271 support software configurable cpu frequency.
272
273 Loongson2F and it's successors support this feature.
274
275 For details, take a look at <file:Documentation/cpu-freq/>.
276
277 If in doubt, say N.
278
279config LOONGSON1_CPUFREQ
280 tristate "Loongson1 CPUFreq Driver"
281 depends on LOONGSON1_LS1B
282 help
283 This option adds a CPUFreq driver for loongson1 processors which
284 support software configurable cpu frequency.
285
286 For details, take a look at <file:Documentation/cpu-freq/>.
287
288 If in doubt, say N.
289endif
290
291if SPARC64
292config SPARC_US3_CPUFREQ
293 tristate "UltraSPARC-III CPU Frequency driver"
294 help
295 This adds the CPUFreq driver for UltraSPARC-III processors.
296
297 For details, take a look at <file:Documentation/cpu-freq>.
298
299 If in doubt, say N.
300
301config SPARC_US2E_CPUFREQ
302 tristate "UltraSPARC-IIe CPU Frequency driver"
303 help
304 This adds the CPUFreq driver for UltraSPARC-IIe processors.
305
306 For details, take a look at <file:Documentation/cpu-freq>.
307
308 If in doubt, say N.
309endif
310
311if SUPERH
312config SH_CPU_FREQ
313 tristate "SuperH CPU Frequency driver"
314 help
315 This adds the cpufreq driver for SuperH. Any CPU that supports
316 clock rate rounding through the clock framework can use this
317 driver. While it will make the kernel slightly larger, this is
318 harmless for CPUs that don't support rate rounding. The driver
319 will also generate a notice in the boot log before disabling
320 itself if the CPU in question is not capable of rate rounding.
321
322 For details, take a look at <file:Documentation/cpu-freq>.
323
324 If unsure, say N.
325endif
326
327config QORIQ_CPUFREQ
328 tristate "CPU frequency scaling driver for Freescale QorIQ SoCs"
329 depends on OF && COMMON_CLK && (PPC_E500MC || ARM || ARM64)
330 depends on !CPU_THERMAL || THERMAL
331 select CLK_QORIQ
332 help
333 This adds the CPUFreq driver support for Freescale QorIQ SoCs
334 which are capable of changing the CPU's frequency dynamically.
335
336endif
337endmenu