xref: /openbmc/linux/drivers/cpufreq/Kconfig.x86 (revision 77d84ff8) 
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	depends on ACPI_PROCESSOR
35	help
36	  This driver adds a CPUFreq driver which utilizes the ACPI
37	  Processor Performance States.
38	  This driver also supports Intel Enhanced Speedstep and newer
39	  AMD CPUs.
40
41	  To compile this driver as a module, choose M here: the
42	  module will be called acpi-cpufreq.
43
44	  For details, take a look at <file:Documentation/cpu-freq/>.
45
46	  If in doubt, say N.
47
48config X86_ACPI_CPUFREQ_CPB
49	default y
50	bool "Legacy cpb sysfs knob support for AMD CPUs"
51	depends on X86_ACPI_CPUFREQ && CPU_SUP_AMD
52	help
53	  The powernow-k8 driver used to provide a sysfs knob called "cpb"
54	  to disable the Core Performance Boosting feature of AMD CPUs. This
55	  file has now been superseeded by the more generic "boost" entry.
56
57	  By enabling this option the acpi_cpufreq driver provides the old
58	  entry in addition to the new boost ones, for compatibility reasons.
59
60config ELAN_CPUFREQ
61	tristate "AMD Elan SC400 and SC410"
62	depends on MELAN
63	---help---
64	  This adds the CPUFreq driver for AMD Elan SC400 and SC410
65	  processors.
66
67	  You need to specify the processor maximum speed as boot
68	  parameter: elanfreq=maxspeed (in kHz) or as module
69	  parameter "max_freq".
70
71	  For details, take a look at <file:Documentation/cpu-freq/>.
72
73	  If in doubt, say N.
74
75config SC520_CPUFREQ
76	tristate "AMD Elan SC520"
77	depends on MELAN
78	---help---
79	  This adds the CPUFreq driver for AMD Elan SC520 processor.
80
81	  For details, take a look at <file:Documentation/cpu-freq/>.
82
83	  If in doubt, say N.
84
85
86config X86_POWERNOW_K6
87	tristate "AMD Mobile K6-2/K6-3 PowerNow!"
88	depends on X86_32
89	help
90	  This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
91	  AMD K6-3+ processors.
92
93	  For details, take a look at <file:Documentation/cpu-freq/>.
94
95	  If in doubt, say N.
96
97config X86_POWERNOW_K7
98	tristate "AMD Mobile Athlon/Duron PowerNow!"
99	depends on X86_32
100	help
101	  This adds the CPUFreq driver for mobile AMD K7 mobile processors.
102
103	  For details, take a look at <file:Documentation/cpu-freq/>.
104
105	  If in doubt, say N.
106
107config X86_POWERNOW_K7_ACPI
108	bool
109	depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
110	depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
111	depends on X86_32
112	default y
113
114config X86_POWERNOW_K8
115	tristate "AMD Opteron/Athlon64 PowerNow!"
116	depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
117	help
118	  This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
119	  Support for K10 and newer processors is now in acpi-cpufreq.
120
121	  To compile this driver as a module, choose M here: the
122	  module will be called powernow-k8.
123
124	  For details, take a look at <file:Documentation/cpu-freq/>.
125
126config X86_AMD_FREQ_SENSITIVITY
127	tristate "AMD frequency sensitivity feedback powersave bias"
128	depends on CPU_FREQ_GOV_ONDEMAND && X86_ACPI_CPUFREQ && CPU_SUP_AMD
129	help
130	  This adds AMD-specific powersave bias function to the ondemand
131	  governor, which allows it to make more power-conscious frequency
132	  change decisions based on feedback from hardware (available on AMD
133	  Family 16h and above).
134
135	  Hardware feedback tells software how "sensitive" to frequency changes
136	  the CPUs' workloads are. CPU-bound workloads will be more sensitive
137	  -- they will perform better as frequency increases. Memory/IO-bound
138	  workloads will be less sensitive -- they will not necessarily perform
139	  better as frequency increases.
140
141	  If in doubt, say N.
142
143config X86_GX_SUSPMOD
144	tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
145	depends on X86_32 && PCI
146	help
147	 This add the CPUFreq driver for NatSemi Geode processors which
148	 support suspend modulation.
149
150	 For details, take a look at <file:Documentation/cpu-freq/>.
151
152	 If in doubt, say N.
153
154config X86_SPEEDSTEP_CENTRINO
155	tristate "Intel Enhanced SpeedStep (deprecated)"
156	select X86_SPEEDSTEP_CENTRINO_TABLE if X86_32
157	depends on X86_32 || (X86_64 && ACPI_PROCESSOR)
158	help
159	  This is deprecated and this functionality is now merged into
160	  acpi_cpufreq (X86_ACPI_CPUFREQ). Use that driver instead of
161	  speedstep_centrino.
162	  This adds the CPUFreq driver for Enhanced SpeedStep enabled
163	  mobile CPUs.  This means Intel Pentium M (Centrino) CPUs
164	  or 64bit enabled Intel Xeons.
165
166	  To compile this driver as a module, choose M here: the
167	  module will be called speedstep-centrino.
168
169	  For details, take a look at <file:Documentation/cpu-freq/>.
170
171	  If in doubt, say N.
172
173config X86_SPEEDSTEP_CENTRINO_TABLE
174	bool "Built-in tables for Banias CPUs"
175	depends on X86_32 && X86_SPEEDSTEP_CENTRINO
176	default y
177	help
178	  Use built-in tables for Banias CPUs if ACPI encoding
179	  is not available.
180
181	  If in doubt, say N.
182
183config X86_SPEEDSTEP_ICH
184	tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
185	depends on X86_32
186	help
187	  This adds the CPUFreq driver for certain mobile Intel Pentium III
188	  (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
189	  mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
190	  ICH3 or ICH4 southbridge.
191
192	  For details, take a look at <file:Documentation/cpu-freq/>.
193
194	  If in doubt, say N.
195
196config X86_SPEEDSTEP_SMI
197	tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
198	depends on X86_32
199	help
200	  This adds the CPUFreq driver for certain mobile Intel Pentium III
201	  (Coppermine), all mobile Intel Pentium III-M (Tualatin)
202	  on systems which have an Intel 440BX/ZX/MX southbridge.
203
204	  For details, take a look at <file:Documentation/cpu-freq/>.
205
206	  If in doubt, say N.
207
208config X86_P4_CLOCKMOD
209	tristate "Intel Pentium 4 clock modulation"
210	help
211	  This adds the CPUFreq driver for Intel Pentium 4 / XEON
212	  processors.  When enabled it will lower CPU temperature by skipping
213	  clocks.
214
215	  This driver should be only used in exceptional
216	  circumstances when very low power is needed because it causes severe
217	  slowdowns and noticeable latencies.  Normally Speedstep should be used
218	  instead.
219
220	  To compile this driver as a module, choose M here: the
221	  module will be called p4-clockmod.
222
223	  For details, take a look at <file:Documentation/cpu-freq/>.
224
225	  Unless you are absolutely sure say N.
226
227config X86_CPUFREQ_NFORCE2
228	tristate "nVidia nForce2 FSB changing"
229	depends on X86_32
230	help
231	  This adds the CPUFreq driver for FSB changing on nVidia nForce2
232	  platforms.
233
234	  For details, take a look at <file:Documentation/cpu-freq/>.
235
236	  If in doubt, say N.
237
238config X86_LONGRUN
239	tristate "Transmeta LongRun"
240	depends on X86_32
241	help
242	  This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
243	  which support LongRun.
244
245	  For details, take a look at <file:Documentation/cpu-freq/>.
246
247	  If in doubt, say N.
248
249config X86_LONGHAUL
250	tristate "VIA Cyrix III Longhaul"
251	depends on X86_32 && ACPI_PROCESSOR
252	help
253	  This adds the CPUFreq driver for VIA Samuel/CyrixIII,
254	  VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
255	  processors.
256
257	  For details, take a look at <file:Documentation/cpu-freq/>.
258
259	  If in doubt, say N.
260
261config X86_E_POWERSAVER
262	tristate "VIA C7 Enhanced PowerSaver (DANGEROUS)"
263	depends on X86_32 && ACPI_PROCESSOR
264	help
265	  This adds the CPUFreq driver for VIA C7 processors.  However, this driver
266	  does not have any safeguards to prevent operating the CPU out of spec
267	  and is thus considered dangerous.  Please use the regular ACPI cpufreq
268	  driver, enabled by CONFIG_X86_ACPI_CPUFREQ.
269
270	  If in doubt, say N.
271
272comment "shared options"
273
274config X86_SPEEDSTEP_LIB
275	tristate
276	default (X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD)
277
278config X86_SPEEDSTEP_RELAXED_CAP_CHECK
279	bool "Relaxed speedstep capability checks"
280	depends on X86_32 && (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
281	help
282	  Don't perform all checks for a speedstep capable system which would
283	  normally be done. Some ancient or strange systems, though speedstep
284	  capable, don't always indicate that they are speedstep capable. This
285	  option lets the probing code bypass some of those checks if the
286	  parameter "relaxed_check=1" is passed to the module.
287
288