xref: /openbmc/linux/drivers/cpufreq/Kconfig.x86 (revision bb0eb050)
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       select ACPI_CPPC_LIB if X86_64 && ACPI && SCHED_MC_PRIO
10       help
11          This driver provides a P state for Intel core processors.
12	  The driver implements an internal governor and will become
13          the scaling driver and governor for Sandy bridge processors.
14
15	  When this driver is enabled it will become the preferred
16          scaling driver for Sandy bridge processors.
17
18	  If in doubt, say N.
19
20config X86_PCC_CPUFREQ
21	tristate "Processor Clocking Control interface driver"
22	depends on ACPI && ACPI_PROCESSOR
23	help
24	  This driver adds support for the PCC interface.
25
26	  For details, take a look at:
27	  <file:Documentation/cpu-freq/pcc-cpufreq.txt>.
28
29	  To compile this driver as a module, choose M here: the
30	  module will be called pcc-cpufreq.
31
32	  If in doubt, say N.
33
34config X86_ACPI_CPUFREQ
35	tristate "ACPI Processor P-States driver"
36	depends on ACPI_PROCESSOR
37	help
38	  This driver adds a CPUFreq driver which utilizes the ACPI
39	  Processor Performance States.
40	  This driver also supports Intel Enhanced Speedstep and newer
41	  AMD CPUs.
42
43	  To compile this driver as a module, choose M here: the
44	  module will be called acpi-cpufreq.
45
46	  For details, take a look at <file:Documentation/cpu-freq/>.
47
48	  If in doubt, say N.
49
50config X86_ACPI_CPUFREQ_CPB
51	default y
52	bool "Legacy cpb sysfs knob support for AMD CPUs"
53	depends on X86_ACPI_CPUFREQ && CPU_SUP_AMD
54	help
55	  The powernow-k8 driver used to provide a sysfs knob called "cpb"
56	  to disable the Core Performance Boosting feature of AMD CPUs. This
57	  file has now been superseded by the more generic "boost" entry.
58
59	  By enabling this option the acpi_cpufreq driver provides the old
60	  entry in addition to the new boost ones, for compatibility reasons.
61
62config X86_SFI_CPUFREQ
63	tristate "SFI Performance-States driver"
64	depends on X86_INTEL_MID && SFI
65	help
66	  This adds a CPUFreq driver for some Silvermont based Intel Atom
67	  architectures like Z34xx and Z35xx which enumerate processor
68	  performance states through SFI.
69
70	  If in doubt, say N.
71
72config ELAN_CPUFREQ
73	tristate "AMD Elan SC400 and SC410"
74	depends on MELAN
75	---help---
76	  This adds the CPUFreq driver for AMD Elan SC400 and SC410
77	  processors.
78
79	  You need to specify the processor maximum speed as boot
80	  parameter: elanfreq=maxspeed (in kHz) or as module
81	  parameter "max_freq".
82
83	  For details, take a look at <file:Documentation/cpu-freq/>.
84
85	  If in doubt, say N.
86
87config SC520_CPUFREQ
88	tristate "AMD Elan SC520"
89	depends on MELAN
90	---help---
91	  This adds the CPUFreq driver for AMD Elan SC520 processor.
92
93	  For details, take a look at <file:Documentation/cpu-freq/>.
94
95	  If in doubt, say N.
96
97
98config X86_POWERNOW_K6
99	tristate "AMD Mobile K6-2/K6-3 PowerNow!"
100	depends on X86_32
101	help
102	  This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
103	  AMD K6-3+ processors.
104
105	  For details, take a look at <file:Documentation/cpu-freq/>.
106
107	  If in doubt, say N.
108
109config X86_POWERNOW_K7
110	tristate "AMD Mobile Athlon/Duron PowerNow!"
111	depends on X86_32
112	help
113	  This adds the CPUFreq driver for mobile AMD K7 mobile processors.
114
115	  For details, take a look at <file:Documentation/cpu-freq/>.
116
117	  If in doubt, say N.
118
119config X86_POWERNOW_K7_ACPI
120	bool
121	depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
122	depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
123	depends on X86_32
124	default y
125
126config X86_POWERNOW_K8
127	tristate "AMD Opteron/Athlon64 PowerNow!"
128	depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
129	help
130	  This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
131	  Support for K10 and newer processors is now in acpi-cpufreq.
132
133	  To compile this driver as a module, choose M here: the
134	  module will be called powernow-k8.
135
136	  For details, take a look at <file:Documentation/cpu-freq/>.
137
138config X86_AMD_FREQ_SENSITIVITY
139	tristate "AMD frequency sensitivity feedback powersave bias"
140	depends on CPU_FREQ_GOV_ONDEMAND && X86_ACPI_CPUFREQ && CPU_SUP_AMD
141	help
142	  This adds AMD-specific powersave bias function to the ondemand
143	  governor, which allows it to make more power-conscious frequency
144	  change decisions based on feedback from hardware (available on AMD
145	  Family 16h and above).
146
147	  Hardware feedback tells software how "sensitive" to frequency changes
148	  the CPUs' workloads are. CPU-bound workloads will be more sensitive
149	  -- they will perform better as frequency increases. Memory/IO-bound
150	  workloads will be less sensitive -- they will not necessarily perform
151	  better as frequency increases.
152
153	  If in doubt, say N.
154
155config X86_GX_SUSPMOD
156	tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
157	depends on X86_32 && PCI
158	help
159	 This add the CPUFreq driver for NatSemi Geode processors which
160	 support suspend modulation.
161
162	 For details, take a look at <file:Documentation/cpu-freq/>.
163
164	 If in doubt, say N.
165
166config X86_SPEEDSTEP_CENTRINO
167	tristate "Intel Enhanced SpeedStep (deprecated)"
168	select X86_SPEEDSTEP_CENTRINO_TABLE if X86_32
169	depends on X86_32 || (X86_64 && ACPI_PROCESSOR)
170	help
171	  This is deprecated and this functionality is now merged into
172	  acpi_cpufreq (X86_ACPI_CPUFREQ). Use that driver instead of
173	  speedstep_centrino.
174	  This adds the CPUFreq driver for Enhanced SpeedStep enabled
175	  mobile CPUs.  This means Intel Pentium M (Centrino) CPUs
176	  or 64bit enabled Intel Xeons.
177
178	  To compile this driver as a module, choose M here: the
179	  module will be called speedstep-centrino.
180
181	  For details, take a look at <file:Documentation/cpu-freq/>.
182
183	  If in doubt, say N.
184
185config X86_SPEEDSTEP_CENTRINO_TABLE
186	bool "Built-in tables for Banias CPUs"
187	depends on X86_32 && X86_SPEEDSTEP_CENTRINO
188	default y
189	help
190	  Use built-in tables for Banias CPUs if ACPI encoding
191	  is not available.
192
193	  If in doubt, say N.
194
195config X86_SPEEDSTEP_ICH
196	tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
197	depends on X86_32
198	help
199	  This adds the CPUFreq driver for certain mobile Intel Pentium III
200	  (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
201	  mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
202	  ICH3 or ICH4 southbridge.
203
204	  For details, take a look at <file:Documentation/cpu-freq/>.
205
206	  If in doubt, say N.
207
208config X86_SPEEDSTEP_SMI
209	tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
210	depends on X86_32
211	help
212	  This adds the CPUFreq driver for certain mobile Intel Pentium III
213	  (Coppermine), all mobile Intel Pentium III-M (Tualatin)
214	  on systems which have an Intel 440BX/ZX/MX southbridge.
215
216	  For details, take a look at <file:Documentation/cpu-freq/>.
217
218	  If in doubt, say N.
219
220config X86_P4_CLOCKMOD
221	tristate "Intel Pentium 4 clock modulation"
222	help
223	  This adds the CPUFreq driver for Intel Pentium 4 / XEON
224	  processors.  When enabled it will lower CPU temperature by skipping
225	  clocks.
226
227	  This driver should be only used in exceptional
228	  circumstances when very low power is needed because it causes severe
229	  slowdowns and noticeable latencies.  Normally Speedstep should be used
230	  instead.
231
232	  To compile this driver as a module, choose M here: the
233	  module will be called p4-clockmod.
234
235	  For details, take a look at <file:Documentation/cpu-freq/>.
236
237	  Unless you are absolutely sure say N.
238
239config X86_CPUFREQ_NFORCE2
240	tristate "nVidia nForce2 FSB changing"
241	depends on X86_32
242	help
243	  This adds the CPUFreq driver for FSB changing on nVidia nForce2
244	  platforms.
245
246	  For details, take a look at <file:Documentation/cpu-freq/>.
247
248	  If in doubt, say N.
249
250config X86_LONGRUN
251	tristate "Transmeta LongRun"
252	depends on X86_32
253	help
254	  This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
255	  which support LongRun.
256
257	  For details, take a look at <file:Documentation/cpu-freq/>.
258
259	  If in doubt, say N.
260
261config X86_LONGHAUL
262	tristate "VIA Cyrix III Longhaul"
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	depends on X86_32 && ACPI_PROCESSOR
276	help
277	  This adds the CPUFreq driver for VIA C7 processors.  However, this driver
278	  does not have any safeguards to prevent operating the CPU out of spec
279	  and is thus considered dangerous.  Please use the regular ACPI cpufreq
280	  driver, enabled by CONFIG_X86_ACPI_CPUFREQ.
281
282	  If in doubt, say N.
283
284comment "shared options"
285
286config X86_SPEEDSTEP_LIB
287	tristate
288	default (X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD)
289
290config X86_SPEEDSTEP_RELAXED_CAP_CHECK
291	bool "Relaxed speedstep capability checks"
292	depends on X86_32 && (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
293	help
294	  Don't perform all checks for a speedstep capable system which would
295	  normally be done. Some ancient or strange systems, though speedstep
296	  capable, don't always indicate that they are speedstep capable. This
297	  option lets the probing code bypass some of those checks if the
298	  parameter "relaxed_check=1" is passed to the module.
299
300