xref: /openbmc/linux/drivers/cpufreq/Kconfig (revision 2d96b44f)
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
40config CPU_FREQ_STAT_DETAILS
41	bool "CPU frequency transition statistics details"
42	depends on CPU_FREQ_STAT
43	help
44	  Show detailed CPU frequency transition table in sysfs.
45
46	  If in doubt, say N.
47
48choice
49	prompt "Default CPUFreq governor"
50	default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1100_CPUFREQ || ARM_SA1110_CPUFREQ
51	default CPU_FREQ_DEFAULT_GOV_PERFORMANCE
52	help
53	  This option sets which CPUFreq governor shall be loaded at
54	  startup. If in doubt, select 'performance'.
55
56config CPU_FREQ_DEFAULT_GOV_PERFORMANCE
57	bool "performance"
58	select CPU_FREQ_GOV_PERFORMANCE
59	help
60	  Use the CPUFreq governor 'performance' as default. This sets
61	  the frequency statically to the highest frequency supported by
62	  the CPU.
63
64config CPU_FREQ_DEFAULT_GOV_POWERSAVE
65	bool "powersave"
66	select CPU_FREQ_GOV_POWERSAVE
67	help
68	  Use the CPUFreq governor 'powersave' as default. This sets
69	  the frequency statically to the lowest frequency supported by
70	  the CPU.
71
72config CPU_FREQ_DEFAULT_GOV_USERSPACE
73	bool "userspace"
74	select CPU_FREQ_GOV_USERSPACE
75	help
76	  Use the CPUFreq governor 'userspace' as default. This allows
77	  you to set the CPU frequency manually or when a userspace
78	  program shall be able to set the CPU dynamically without having
79	  to enable the userspace governor manually.
80
81config CPU_FREQ_DEFAULT_GOV_ONDEMAND
82	bool "ondemand"
83	select CPU_FREQ_GOV_ONDEMAND
84	select CPU_FREQ_GOV_PERFORMANCE
85	help
86	  Use the CPUFreq governor 'ondemand' as default. This allows
87	  you to get a full dynamic frequency capable system by simply
88	  loading your cpufreq low-level hardware driver.
89	  Be aware that not all cpufreq drivers support the ondemand
90	  governor. If unsure have a look at the help section of the
91	  driver. Fallback governor will be the performance governor.
92
93config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
94	bool "conservative"
95	select CPU_FREQ_GOV_CONSERVATIVE
96	select CPU_FREQ_GOV_PERFORMANCE
97	help
98	  Use the CPUFreq governor 'conservative' as default. This allows
99	  you to get a full dynamic frequency capable system by simply
100	  loading your cpufreq low-level hardware driver.
101	  Be aware that not all cpufreq drivers support the conservative
102	  governor. If unsure have a look at the help section of the
103	  driver. Fallback governor will be the performance governor.
104
105config CPU_FREQ_DEFAULT_GOV_SCHEDUTIL
106	bool "schedutil"
107	depends on SMP
108	select CPU_FREQ_GOV_SCHEDUTIL
109	select CPU_FREQ_GOV_PERFORMANCE
110	help
111	  Use the 'schedutil' CPUFreq governor by default. If unsure,
112	  have a look at the help section of that governor. The fallback
113	  governor will be 'performance'.
114
115endchoice
116
117config CPU_FREQ_GOV_PERFORMANCE
118	tristate "'performance' governor"
119	help
120	  This cpufreq governor sets the frequency statically to the
121	  highest available CPU frequency.
122
123	  To compile this driver as a module, choose M here: the
124	  module will be called cpufreq_performance.
125
126	  If in doubt, say Y.
127
128config CPU_FREQ_GOV_POWERSAVE
129	tristate "'powersave' governor"
130	help
131	  This cpufreq governor sets the frequency statically to the
132	  lowest available CPU frequency.
133
134	  To compile this driver as a module, choose M here: the
135	  module will be called cpufreq_powersave.
136
137	  If in doubt, say Y.
138
139config CPU_FREQ_GOV_USERSPACE
140	tristate "'userspace' governor for userspace frequency scaling"
141	help
142	  Enable this cpufreq governor when you either want to set the
143	  CPU frequency manually or when a userspace program shall
144	  be able to set the CPU dynamically, like on LART
145	  <http://www.lartmaker.nl/>.
146
147	  To compile this driver as a module, choose M here: the
148	  module will be called cpufreq_userspace.
149
150	  For details, take a look at <file:Documentation/cpu-freq/>.
151
152	  If in doubt, say Y.
153
154config CPU_FREQ_GOV_ONDEMAND
155	tristate "'ondemand' cpufreq policy governor"
156	select CPU_FREQ_GOV_COMMON
157	help
158	  'ondemand' - This driver adds a dynamic cpufreq policy governor.
159	  The governor does a periodic polling and
160	  changes frequency based on the CPU utilization.
161	  The support for this governor depends on CPU capability to
162	  do fast frequency switching (i.e, very low latency frequency
163	  transitions).
164
165	  To compile this driver as a module, choose M here: the
166	  module will be called cpufreq_ondemand.
167
168	  For details, take a look at linux/Documentation/cpu-freq.
169
170	  If in doubt, say N.
171
172config CPU_FREQ_GOV_CONSERVATIVE
173	tristate "'conservative' cpufreq governor"
174	depends on CPU_FREQ
175	select CPU_FREQ_GOV_COMMON
176	help
177	  'conservative' - this driver is rather similar to the 'ondemand'
178	  governor both in its source code and its purpose, the difference is
179	  its optimisation for better suitability in a battery powered
180	  environment.  The frequency is gracefully increased and decreased
181	  rather than jumping to 100% when speed is required.
182
183	  If you have a desktop machine then you should really be considering
184	  the 'ondemand' governor instead, however if you are using a laptop,
185	  PDA or even an AMD64 based computer (due to the unacceptable
186	  step-by-step latency issues between the minimum and maximum frequency
187	  transitions in the CPU) you will probably want to use this governor.
188
189	  To compile this driver as a module, choose M here: the
190	  module will be called cpufreq_conservative.
191
192	  For details, take a look at linux/Documentation/cpu-freq.
193
194	  If in doubt, say N.
195
196config CPU_FREQ_GOV_SCHEDUTIL
197	bool "'schedutil' cpufreq policy governor"
198	depends on CPU_FREQ && SMP
199	select CPU_FREQ_GOV_ATTR_SET
200	select IRQ_WORK
201	help
202	  This governor makes decisions based on the utilization data provided
203	  by the scheduler.  It sets the CPU frequency to be proportional to
204	  the utilization/capacity ratio coming from the scheduler.  If the
205	  utilization is frequency-invariant, the new frequency is also
206	  proportional to the maximum available frequency.  If that is not the
207	  case, it is proportional to the current frequency of the CPU.  The
208	  frequency tipping point is at utilization/capacity equal to 80% in
209	  both cases.
210
211	  If in doubt, say N.
212
213comment "CPU frequency scaling drivers"
214
215config CPUFREQ_DT
216	tristate "Generic DT based cpufreq driver"
217	depends on HAVE_CLK && OF
218	# if CPU_THERMAL is on and THERMAL=m, CPUFREQ_DT cannot be =y:
219	depends on !CPU_THERMAL || THERMAL
220	select CPUFREQ_DT_PLATDEV
221	select PM_OPP
222	help
223	  This adds a generic DT based cpufreq driver for frequency management.
224	  It supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
225	  systems.
226
227	  If in doubt, say N.
228
229config CPUFREQ_DT_PLATDEV
230	bool
231	help
232	  This adds a generic DT based cpufreq platdev driver for frequency
233	  management.  This creates a 'cpufreq-dt' platform device, on the
234	  supported platforms.
235
236	  If in doubt, say N.
237
238if X86
239source "drivers/cpufreq/Kconfig.x86"
240endif
241
242if ARM || ARM64
243source "drivers/cpufreq/Kconfig.arm"
244endif
245
246if PPC32 || PPC64
247source "drivers/cpufreq/Kconfig.powerpc"
248endif
249
250if AVR32
251config AVR32_AT32AP_CPUFREQ
252	bool "CPU frequency driver for AT32AP"
253	depends on PLATFORM_AT32AP
254	default n
255	help
256	  This enables the CPU frequency driver for AT32AP processors.
257	  If in doubt, say N.
258endif
259
260if IA64
261config IA64_ACPI_CPUFREQ
262	tristate "ACPI Processor P-States driver"
263	depends on ACPI_PROCESSOR
264	help
265	This driver adds a CPUFreq driver which utilizes the ACPI
266	Processor Performance States.
267
268	For details, take a look at <file:Documentation/cpu-freq/>.
269
270	If in doubt, say N.
271endif
272
273if MIPS
274config LOONGSON2_CPUFREQ
275	tristate "Loongson2 CPUFreq Driver"
276	help
277	  This option adds a CPUFreq driver for loongson processors which
278	  support software configurable cpu frequency.
279
280	  Loongson2F and it's successors support this feature.
281
282	  For details, take a look at <file:Documentation/cpu-freq/>.
283
284	  If in doubt, say N.
285
286config LOONGSON1_CPUFREQ
287	tristate "Loongson1 CPUFreq Driver"
288	help
289	  This option adds a CPUFreq driver for loongson1 processors which
290	  support software configurable cpu frequency.
291
292	  For details, take a look at <file:Documentation/cpu-freq/>.
293
294	  If in doubt, say N.
295endif
296
297if SPARC64
298config SPARC_US3_CPUFREQ
299	tristate "UltraSPARC-III CPU Frequency driver"
300	help
301	  This adds the CPUFreq driver for UltraSPARC-III processors.
302
303	  For details, take a look at <file:Documentation/cpu-freq>.
304
305	  If in doubt, say N.
306
307config SPARC_US2E_CPUFREQ
308	tristate "UltraSPARC-IIe CPU Frequency driver"
309	help
310	  This adds the CPUFreq driver for UltraSPARC-IIe processors.
311
312	  For details, take a look at <file:Documentation/cpu-freq>.
313
314	  If in doubt, say N.
315endif
316
317if SUPERH
318config SH_CPU_FREQ
319	tristate "SuperH CPU Frequency driver"
320	help
321	  This adds the cpufreq driver for SuperH. Any CPU that supports
322	  clock rate rounding through the clock framework can use this
323	  driver. While it will make the kernel slightly larger, this is
324	  harmless for CPUs that don't support rate rounding. The driver
325	  will also generate a notice in the boot log before disabling
326	  itself if the CPU in question is not capable of rate rounding.
327
328	  For details, take a look at <file:Documentation/cpu-freq>.
329
330	  If unsure, say N.
331endif
332
333config QORIQ_CPUFREQ
334	tristate "CPU frequency scaling driver for Freescale QorIQ SoCs"
335	depends on OF && COMMON_CLK && (PPC_E500MC || ARM)
336	depends on !CPU_THERMAL || THERMAL
337	select CLK_QORIQ
338	help
339	  This adds the CPUFreq driver support for Freescale QorIQ SoCs
340	  which are capable of changing the CPU's frequency dynamically.
341
342endif
343endmenu
344