xref: /linux/drivers/cpufreq/Kconfig.x86 (revision 1e1159bb97cf4191849b4b03f77ab32977c2ece6)
1#
2# x86 CPU Frequency scaling drivers
3#
4
5config X86_INTEL_PSTATE
6       bool "Intel P state control"
7       depends on X86
8       help
9          This driver provides a P state for Intel core processors.
10	  The driver implements an internal governor and will become
11          the scaling driver and governor for Sandy bridge processors.
12
13	  When this driver is enabled it will become the perferred
14          scaling driver for Sandy bridge processors.
15
16	  If in doubt, say N.
17
18config X86_PCC_CPUFREQ
19	tristate "Processor Clocking Control interface driver"
20	depends on ACPI && ACPI_PROCESSOR
21	help
22	  This driver adds support for the PCC interface.
23
24	  For details, take a look at:
25	  <file:Documentation/cpu-freq/pcc-cpufreq.txt>.
26
27	  To compile this driver as a module, choose M here: the
28	  module will be called pcc-cpufreq.
29
30	  If in doubt, say N.
31
32config X86_ACPI_CPUFREQ
33	tristate "ACPI Processor P-States driver"
34	select CPU_FREQ_TABLE
35	depends on ACPI_PROCESSOR
36	help
37	  This driver adds a CPUFreq driver which utilizes the ACPI
38	  Processor Performance States.
39	  This driver also supports Intel Enhanced Speedstep and newer
40	  AMD CPUs.
41
42	  To compile this driver as a module, choose M here: the
43	  module will be called acpi-cpufreq.
44
45	  For details, take a look at <file:Documentation/cpu-freq/>.
46
47	  If in doubt, say N.
48
49config X86_ACPI_CPUFREQ_CPB
50	default y
51	bool "Legacy cpb sysfs knob support for AMD CPUs"
52	depends on X86_ACPI_CPUFREQ && CPU_SUP_AMD
53	help
54	  The powernow-k8 driver used to provide a sysfs knob called "cpb"
55	  to disable the Core Performance Boosting feature of AMD CPUs. This
56	  file has now been superseeded by the more generic "boost" entry.
57
58	  By enabling this option the acpi_cpufreq driver provides the old
59	  entry in addition to the new boost ones, for compatibility reasons.
60
61config ELAN_CPUFREQ
62	tristate "AMD Elan SC400 and SC410"
63	select CPU_FREQ_TABLE
64	depends on MELAN
65	---help---
66	  This adds the CPUFreq driver for AMD Elan SC400 and SC410
67	  processors.
68
69	  You need to specify the processor maximum speed as boot
70	  parameter: elanfreq=maxspeed (in kHz) or as module
71	  parameter "max_freq".
72
73	  For details, take a look at <file:Documentation/cpu-freq/>.
74
75	  If in doubt, say N.
76
77config SC520_CPUFREQ
78	tristate "AMD Elan SC520"
79	select CPU_FREQ_TABLE
80	depends on MELAN
81	---help---
82	  This adds the CPUFreq driver for AMD Elan SC520 processor.
83
84	  For details, take a look at <file:Documentation/cpu-freq/>.
85
86	  If in doubt, say N.
87
88
89config X86_POWERNOW_K6
90	tristate "AMD Mobile K6-2/K6-3 PowerNow!"
91	select CPU_FREQ_TABLE
92	depends on X86_32
93	help
94	  This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
95	  AMD K6-3+ processors.
96
97	  For details, take a look at <file:Documentation/cpu-freq/>.
98
99	  If in doubt, say N.
100
101config X86_POWERNOW_K7
102	tristate "AMD Mobile Athlon/Duron PowerNow!"
103	select CPU_FREQ_TABLE
104	depends on X86_32
105	help
106	  This adds the CPUFreq driver for mobile AMD K7 mobile processors.
107
108	  For details, take a look at <file:Documentation/cpu-freq/>.
109
110	  If in doubt, say N.
111
112config X86_POWERNOW_K7_ACPI
113	bool
114	depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
115	depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
116	depends on X86_32
117	default y
118
119config X86_POWERNOW_K8
120	tristate "AMD Opteron/Athlon64 PowerNow!"
121	select CPU_FREQ_TABLE
122	depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
123	help
124	  This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
125	  Support for K10 and newer processors is now in acpi-cpufreq.
126
127	  To compile this driver as a module, choose M here: the
128	  module will be called powernow-k8.
129
130	  For details, take a look at <file:Documentation/cpu-freq/>.
131
132config X86_AMD_FREQ_SENSITIVITY
133	tristate "AMD frequency sensitivity feedback powersave bias"
134	depends on CPU_FREQ_GOV_ONDEMAND && X86_ACPI_CPUFREQ && CPU_SUP_AMD
135	select CPU_FREQ_TABLE
136	help
137	  This adds AMD-specific powersave bias function to the ondemand
138	  governor, which allows it to make more power-conscious frequency
139	  change decisions based on feedback from hardware (availble on AMD
140	  Family 16h and above).
141
142	  Hardware feedback tells software how "sensitive" to frequency changes
143	  the CPUs' workloads are. CPU-bound workloads will be more sensitive
144	  -- they will perform better as frequency increases. Memory/IO-bound
145	  workloads will be less sensitive -- they will not necessarily perform
146	  better as frequency increases.
147
148	  If in doubt, say N.
149
150config X86_GX_SUSPMOD
151	tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
152	depends on X86_32 && PCI
153	help
154	 This add the CPUFreq driver for NatSemi Geode processors which
155	 support suspend modulation.
156
157	 For details, take a look at <file:Documentation/cpu-freq/>.
158
159	 If in doubt, say N.
160
161config X86_SPEEDSTEP_CENTRINO
162	tristate "Intel Enhanced SpeedStep (deprecated)"
163	select CPU_FREQ_TABLE
164	select X86_SPEEDSTEP_CENTRINO_TABLE if X86_32
165	depends on X86_32 || (X86_64 && ACPI_PROCESSOR)
166	help
167	  This is deprecated and this functionality is now merged into
168	  acpi_cpufreq (X86_ACPI_CPUFREQ). Use that driver instead of
169	  speedstep_centrino.
170	  This adds the CPUFreq driver for Enhanced SpeedStep enabled
171	  mobile CPUs.  This means Intel Pentium M (Centrino) CPUs
172	  or 64bit enabled Intel Xeons.
173
174	  To compile this driver as a module, choose M here: the
175	  module will be called speedstep-centrino.
176
177	  For details, take a look at <file:Documentation/cpu-freq/>.
178
179	  If in doubt, say N.
180
181config X86_SPEEDSTEP_CENTRINO_TABLE
182	bool "Built-in tables for Banias CPUs"
183	depends on X86_32 && X86_SPEEDSTEP_CENTRINO
184	default y
185	help
186	  Use built-in tables for Banias CPUs if ACPI encoding
187	  is not available.
188
189	  If in doubt, say N.
190
191config X86_SPEEDSTEP_ICH
192	tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
193	select CPU_FREQ_TABLE
194	depends on X86_32
195	help
196	  This adds the CPUFreq driver for certain mobile Intel Pentium III
197	  (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
198	  mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
199	  ICH3 or ICH4 southbridge.
200
201	  For details, take a look at <file:Documentation/cpu-freq/>.
202
203	  If in doubt, say N.
204
205config X86_SPEEDSTEP_SMI
206	tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
207	select CPU_FREQ_TABLE
208	depends on X86_32
209	help
210	  This adds the CPUFreq driver for certain mobile Intel Pentium III
211	  (Coppermine), all mobile Intel Pentium III-M (Tualatin)
212	  on systems which have an Intel 440BX/ZX/MX southbridge.
213
214	  For details, take a look at <file:Documentation/cpu-freq/>.
215
216	  If in doubt, say N.
217
218config X86_P4_CLOCKMOD
219	tristate "Intel Pentium 4 clock modulation"
220	select CPU_FREQ_TABLE
221	help
222	  This adds the CPUFreq driver for Intel Pentium 4 / XEON
223	  processors.  When enabled it will lower CPU temperature by skipping
224	  clocks.
225
226	  This driver should be only used in exceptional
227	  circumstances when very low power is needed because it causes severe
228	  slowdowns and noticeable latencies.  Normally Speedstep should be used
229	  instead.
230
231	  To compile this driver as a module, choose M here: the
232	  module will be called p4-clockmod.
233
234	  For details, take a look at <file:Documentation/cpu-freq/>.
235
236	  Unless you are absolutely sure say N.
237
238config X86_CPUFREQ_NFORCE2
239	tristate "nVidia nForce2 FSB changing"
240	depends on X86_32
241	help
242	  This adds the CPUFreq driver for FSB changing on nVidia nForce2
243	  platforms.
244
245	  For details, take a look at <file:Documentation/cpu-freq/>.
246
247	  If in doubt, say N.
248
249config X86_LONGRUN
250	tristate "Transmeta LongRun"
251	depends on X86_32
252	help
253	  This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
254	  which support LongRun.
255
256	  For details, take a look at <file:Documentation/cpu-freq/>.
257
258	  If in doubt, say N.
259
260config X86_LONGHAUL
261	tristate "VIA Cyrix III Longhaul"
262	select CPU_FREQ_TABLE
263	depends on X86_32 && ACPI_PROCESSOR
264	help
265	  This adds the CPUFreq driver for VIA Samuel/CyrixIII,
266	  VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
267	  processors.
268
269	  For details, take a look at <file:Documentation/cpu-freq/>.
270
271	  If in doubt, say N.
272
273config X86_E_POWERSAVER
274	tristate "VIA C7 Enhanced PowerSaver (DANGEROUS)"
275	select CPU_FREQ_TABLE
276	depends on X86_32 && ACPI_PROCESSOR
277	help
278	  This adds the CPUFreq driver for VIA C7 processors.  However, this driver
279	  does not have any safeguards to prevent operating the CPU out of spec
280	  and is thus considered dangerous.  Please use the regular ACPI cpufreq
281	  driver, enabled by CONFIG_X86_ACPI_CPUFREQ.
282
283	  If in doubt, say N.
284
285comment "shared options"
286
287config X86_SPEEDSTEP_LIB
288	tristate
289	default (X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD)
290
291config X86_SPEEDSTEP_RELAXED_CAP_CHECK
292	bool "Relaxed speedstep capability checks"
293	depends on X86_32 && (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
294	help
295	  Don't perform all checks for a speedstep capable system which would
296	  normally be done. Some ancient or strange systems, though speedstep
297	  capable, don't always indicate that they are speedstep capable. This
298	  option lets the probing code bypass some of those checks if the
299	  parameter "relaxed_check=1" is passed to the module.
300
301