xref: /openbmc/linux/drivers/cpufreq/Kconfig.x86 (revision 9cfc5c90) 
1#
2# x86 CPU Frequency scaling drivers
3#
4
5config X86_INTEL_PSTATE
6       bool "Intel P state control"
7       depends on X86
8       select ACPI_PROCESSOR if ACPI
9       help
10          This driver provides a P state for Intel core processors.
11	  The driver implements an internal governor and will become
12          the scaling driver and governor for Sandy bridge processors.
13
14	  When this driver is enabled it will become the preferred
15          scaling driver for Sandy bridge processors.
16
17	  If in doubt, say N.
18
19config X86_PCC_CPUFREQ
20	tristate "Processor Clocking Control interface driver"
21	depends on ACPI && ACPI_PROCESSOR
22	help
23	  This driver adds support for the PCC interface.
24
25	  For details, take a look at:
26	  <file:Documentation/cpu-freq/pcc-cpufreq.txt>.
27
28	  To compile this driver as a module, choose M here: the
29	  module will be called pcc-cpufreq.
30
31	  If in doubt, say N.
32
33config X86_ACPI_CPUFREQ
34	tristate "ACPI Processor P-States driver"
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56	  file has now been superseded by the more generic "boost" entry.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 X86_SFI_CPUFREQ
62	tristate "SFI Performance-States driver"
63	depends on X86_INTEL_MID && SFI
64	help
65	  This adds a CPUFreq driver for some Silvermont based Intel Atom
66	  architectures like Z34xx and Z35xx which enumerate processor
67	  performance states through SFI.
68
69	  If in doubt, say N.
70
71config ELAN_CPUFREQ
72	tristate "AMD Elan SC400 and SC410"
73	depends on MELAN
74	---help---
75	  This adds the CPUFreq driver for AMD Elan SC400 and SC410
76	  processors.
77
78	  You need to specify the processor maximum speed as boot
79	  parameter: elanfreq=maxspeed (in kHz) or as module
80	  parameter "max_freq".
81
82	  For details, take a look at <file:Documentation/cpu-freq/>.
83
84	  If in doubt, say N.
85
86config SC520_CPUFREQ
87	tristate "AMD Elan SC520"
88	depends on MELAN
89	---help---
90	  This adds the CPUFreq driver for AMD Elan SC520 processor.
91
92	  For details, take a look at <file:Documentation/cpu-freq/>.
93
94	  If in doubt, say N.
95
96
97config X86_POWERNOW_K6
98	tristate "AMD Mobile K6-2/K6-3 PowerNow!"
99	depends on X86_32
100	help
101	  This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
102	  AMD K6-3+ processors.
103
104	  For details, take a look at <file:Documentation/cpu-freq/>.
105
106	  If in doubt, say N.
107
108config X86_POWERNOW_K7
109	tristate "AMD Mobile Athlon/Duron PowerNow!"
110	depends on X86_32
111	help
112	  This adds the CPUFreq driver for mobile AMD K7 mobile processors.
113
114	  For details, take a look at <file:Documentation/cpu-freq/>.
115
116	  If in doubt, say N.
117
118config X86_POWERNOW_K7_ACPI
119	bool
120	depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
121	depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
122	depends on X86_32
123	default y
124
125config X86_POWERNOW_K8
126	tristate "AMD Opteron/Athlon64 PowerNow!"
127	depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
128	help
129	  This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
130	  Support for K10 and newer processors is now in acpi-cpufreq.
131
132	  To compile this driver as a module, choose M here: the
133	  module will be called powernow-k8.
134
135	  For details, take a look at <file:Documentation/cpu-freq/>.
136
137config X86_AMD_FREQ_SENSITIVITY
138	tristate "AMD frequency sensitivity feedback powersave bias"
139	depends on CPU_FREQ_GOV_ONDEMAND && X86_ACPI_CPUFREQ && CPU_SUP_AMD
140	help
141	  This adds AMD-specific powersave bias function to the ondemand
142	  governor, which allows it to make more power-conscious frequency
143	  change decisions based on feedback from hardware (available on AMD
144	  Family 16h and above).
145
146	  Hardware feedback tells software how "sensitive" to frequency changes
147	  the CPUs' workloads are. CPU-bound workloads will be more sensitive
148	  -- they will perform better as frequency increases. Memory/IO-bound
149	  workloads will be less sensitive -- they will not necessarily perform
150	  better as frequency increases.
151
152	  If in doubt, say N.
153
154config X86_GX_SUSPMOD
155	tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
156	depends on X86_32 && PCI
157	help
158	 This add the CPUFreq driver for NatSemi Geode processors which
159	 support suspend modulation.
160
161	 For details, take a look at <file:Documentation/cpu-freq/>.
162
163	 If in doubt, say N.
164
165config X86_SPEEDSTEP_CENTRINO
166	tristate "Intel Enhanced SpeedStep (deprecated)"
167	select X86_SPEEDSTEP_CENTRINO_TABLE if X86_32
168	depends on X86_32 || (X86_64 && ACPI_PROCESSOR)
169	help
170	  This is deprecated and this functionality is now merged into
171	  acpi_cpufreq (X86_ACPI_CPUFREQ). Use that driver instead of
172	  speedstep_centrino.
173	  This adds the CPUFreq driver for Enhanced SpeedStep enabled
174	  mobile CPUs.  This means Intel Pentium M (Centrino) CPUs
175	  or 64bit enabled Intel Xeons.
176
177	  To compile this driver as a module, choose M here: the
178	  module will be called speedstep-centrino.
179
180	  For details, take a look at <file:Documentation/cpu-freq/>.
181
182	  If in doubt, say N.
183
184config X86_SPEEDSTEP_CENTRINO_TABLE
185	bool "Built-in tables for Banias CPUs"
186	depends on X86_32 && X86_SPEEDSTEP_CENTRINO
187	default y
188	help
189	  Use built-in tables for Banias CPUs if ACPI encoding
190	  is not available.
191
192	  If in doubt, say N.
193
194config X86_SPEEDSTEP_ICH
195	tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
196	depends on X86_32
197	help
198	  This adds the CPUFreq driver for certain mobile Intel Pentium III
199	  (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
200	  mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
201	  ICH3 or ICH4 southbridge.
202
203	  For details, take a look at <file:Documentation/cpu-freq/>.
204
205	  If in doubt, say N.
206
207config X86_SPEEDSTEP_SMI
208	tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
209	depends on X86_32
210	help
211	  This adds the CPUFreq driver for certain mobile Intel Pentium III
212	  (Coppermine), all mobile Intel Pentium III-M (Tualatin)
213	  on systems which have an Intel 440BX/ZX/MX southbridge.
214
215	  For details, take a look at <file:Documentation/cpu-freq/>.
216
217	  If in doubt, say N.
218
219config X86_P4_CLOCKMOD
220	tristate "Intel Pentium 4 clock modulation"
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	depends on X86_32 && ACPI_PROCESSOR
263	help
264	  This adds the CPUFreq driver for VIA Samuel/CyrixIII,
265	  VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
266	  processors.
267
268	  For details, take a look at <file:Documentation/cpu-freq/>.
269
270	  If in doubt, say N.
271
272config X86_E_POWERSAVER
273	tristate "VIA C7 Enhanced PowerSaver (DANGEROUS)"
274	depends on X86_32 && ACPI_PROCESSOR
275	help
276	  This adds the CPUFreq driver for VIA C7 processors.  However, this driver
277	  does not have any safeguards to prevent operating the CPU out of spec
278	  and is thus considered dangerous.  Please use the regular ACPI cpufreq
279	  driver, enabled by CONFIG_X86_ACPI_CPUFREQ.
280
281	  If in doubt, say N.
282
283comment "shared options"
284
285config X86_SPEEDSTEP_LIB
286	tristate
287	default (X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD)
288
289config X86_SPEEDSTEP_RELAXED_CAP_CHECK
290	bool "Relaxed speedstep capability checks"
291	depends on X86_32 && (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
292	help
293	  Don't perform all checks for a speedstep capable system which would
294	  normally be done. Some ancient or strange systems, though speedstep
295	  capable, don't always indicate that they are speedstep capable. This
296	  option lets the probing code bypass some of those checks if the
297	  parameter "relaxed_check=1" is passed to the module.
298
299