[linux-2.6-block.git] / drivers / cpufreq / Kconfig

menu "CPU Frequency scaling"

config CPU_FREQ
	bool "CPU Frequency scaling"
	select SRCU
	help
	  CPU Frequency scaling allows you to change the clock speed of 
	  CPUs on the fly. This is a nice method to save power, because 
	  the lower the CPU clock speed, the less power the CPU consumes.

	  Note that this driver doesn't automatically change the CPU
	  clock speed, you need to either enable a dynamic cpufreq governor
	  (see below) after boot, or use a userspace tool.

	  For details, take a look at <file:Documentation/cpu-freq>.

	  If in doubt, say N.

if CPU_FREQ

config CPU_FREQ_GOV_COMMON
	select IRQ_WORK
	bool

config CPU_FREQ_BOOST_SW
	bool
	depends on THERMAL

config CPU_FREQ_STAT
	tristate "CPU frequency translation statistics"
	default y
	help
	  This driver exports CPU frequency statistics information through sysfs
	  file system.

	  To compile this driver as a module, choose M here: the
	  module will be called cpufreq_stats.

	  If in doubt, say N.

config CPU_FREQ_STAT_DETAILS
	bool "CPU frequency translation statistics details"
	depends on CPU_FREQ_STAT
	help
	  This will show detail CPU frequency translation table in sysfs file
	  system.

	  If in doubt, say N.

choice
	prompt "Default CPUFreq governor"
	default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1100_CPUFREQ || ARM_SA1110_CPUFREQ
	default CPU_FREQ_DEFAULT_GOV_PERFORMANCE
	help
	  This option sets which CPUFreq governor shall be loaded at
	  startup. If in doubt, select 'performance'.

config CPU_FREQ_DEFAULT_GOV_PERFORMANCE
	bool "performance"
	select CPU_FREQ_GOV_PERFORMANCE
	help
	  Use the CPUFreq governor 'performance' as default. This sets
	  the frequency statically to the highest frequency supported by
	  the CPU.

config CPU_FREQ_DEFAULT_GOV_POWERSAVE
	bool "powersave"
	select CPU_FREQ_GOV_POWERSAVE
	help
	  Use the CPUFreq governor 'powersave' as default. This sets
	  the frequency statically to the lowest frequency supported by
	  the CPU.

config CPU_FREQ_DEFAULT_GOV_USERSPACE
	bool "userspace"
	select CPU_FREQ_GOV_USERSPACE
	help
	  Use the CPUFreq governor 'userspace' as default. This allows
	  you to set the CPU frequency manually or when a userspace 
	  program shall be able to set the CPU dynamically without having
	  to enable the userspace governor manually.

config CPU_FREQ_DEFAULT_GOV_ONDEMAND
	bool "ondemand"
	select CPU_FREQ_GOV_ONDEMAND
	select CPU_FREQ_GOV_PERFORMANCE
	help
	  Use the CPUFreq governor 'ondemand' as default. This allows
	  you to get a full dynamic frequency capable system by simply
	  loading your cpufreq low-level hardware driver.
	  Be aware that not all cpufreq drivers support the ondemand
	  governor. If unsure have a look at the help section of the
	  driver. Fallback governor will be the performance governor.

config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
	bool "conservative"
	select CPU_FREQ_GOV_CONSERVATIVE
	select CPU_FREQ_GOV_PERFORMANCE
	help
	  Use the CPUFreq governor 'conservative' as default. This allows
	  you to get a full dynamic frequency capable system by simply
	  loading your cpufreq low-level hardware driver.
	  Be aware that not all cpufreq drivers support the conservative
	  governor. If unsure have a look at the help section of the
	  driver. Fallback governor will be the performance governor.
endchoice

config CPU_FREQ_GOV_PERFORMANCE
	tristate "'performance' governor"
	help
	  This cpufreq governor sets the frequency statically to the
	  highest available CPU frequency.

	  To compile this driver as a module, choose M here: the
	  module will be called cpufreq_performance.

	  If in doubt, say Y.

config CPU_FREQ_GOV_POWERSAVE
	tristate "'powersave' governor"
	help
	  This cpufreq governor sets the frequency statically to the
	  lowest available CPU frequency.

	  To compile this driver as a module, choose M here: the
	  module will be called cpufreq_powersave.

	  If in doubt, say Y.

config CPU_FREQ_GOV_USERSPACE
	tristate "'userspace' governor for userspace frequency scaling"
	help
	  Enable this cpufreq governor when you either want to set the
	  CPU frequency manually or when a userspace program shall
	  be able to set the CPU dynamically, like on LART 
	  <http://www.lartmaker.nl/>.

	  To compile this driver as a module, choose M here: the
	  module will be called cpufreq_userspace.

	  For details, take a look at <file:Documentation/cpu-freq/>.

	  If in doubt, say Y.

config CPU_FREQ_GOV_ONDEMAND
	tristate "'ondemand' cpufreq policy governor"
	select CPU_FREQ_GOV_COMMON
	help
	  'ondemand' - This driver adds a dynamic cpufreq policy governor.
	  The governor does a periodic polling and 
	  changes frequency based on the CPU utilization.
	  The support for this governor depends on CPU capability to
	  do fast frequency switching (i.e, very low latency frequency
	  transitions). 

	  To compile this driver as a module, choose M here: the
	  module will be called cpufreq_ondemand.

	  For details, take a look at linux/Documentation/cpu-freq.

	  If in doubt, say N.

config CPU_FREQ_GOV_CONSERVATIVE
	tristate "'conservative' cpufreq governor"
	depends on CPU_FREQ
	select CPU_FREQ_GOV_COMMON
	help
	  'conservative' - this driver is rather similar to the 'ondemand'
	  governor both in its source code and its purpose, the difference is
	  its optimisation for better suitability in a battery powered
	  environment.  The frequency is gracefully increased and decreased
	  rather than jumping to 100% when speed is required.

	  If you have a desktop machine then you should really be considering
	  the 'ondemand' governor instead, however if you are using a laptop,
	  PDA or even an AMD64 based computer (due to the unacceptable
	  step-by-step latency issues between the minimum and maximum frequency
	  transitions in the CPU) you will probably want to use this governor.

	  To compile this driver as a module, choose M here: the
	  module will be called cpufreq_conservative.

	  For details, take a look at linux/Documentation/cpu-freq.

	  If in doubt, say N.

comment "CPU frequency scaling drivers"

config CPUFREQ_DT
	tristate "Generic DT based cpufreq driver"
	depends on HAVE_CLK && OF
	# if CPU_THERMAL is on and THERMAL=m, CPUFREQ_DT cannot be =y:
	depends on !CPU_THERMAL || THERMAL
	select PM_OPP
	help
	  This adds a generic DT based cpufreq driver for frequency management.
	  It supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
	  systems which share clock and voltage across all CPUs.

	  If in doubt, say N.

if X86
source "drivers/cpufreq/Kconfig.x86"
endif

if ARM || ARM64
source "drivers/cpufreq/Kconfig.arm"
endif

if PPC32 || PPC64
source "drivers/cpufreq/Kconfig.powerpc"
endif

if AVR32
config AVR32_AT32AP_CPUFREQ
	bool "CPU frequency driver for AT32AP"
	depends on PLATFORM_AT32AP
	default n
	help
	  This enables the CPU frequency driver for AT32AP processors.
	  If in doubt, say N.
endif

if IA64
config IA64_ACPI_CPUFREQ
	tristate "ACPI Processor P-States driver"
	depends on ACPI_PROCESSOR
	help
	This driver adds a CPUFreq driver which utilizes the ACPI
	Processor Performance States.

	For details, take a look at <file:Documentation/cpu-freq/>.

	If in doubt, say N.
endif

if MIPS
config LOONGSON2_CPUFREQ
	tristate "Loongson2 CPUFreq Driver"
	help
	  This option adds a CPUFreq driver for loongson processors which
	  support software configurable cpu frequency.

	  Loongson2F and it's successors support this feature.

	  For details, take a look at <file:Documentation/cpu-freq/>.

	  If in doubt, say N.

config LOONGSON1_CPUFREQ
	tristate "Loongson1 CPUFreq Driver"
	help
	  This option adds a CPUFreq driver for loongson1 processors which
	  support software configurable cpu frequency.

	  For details, take a look at <file:Documentation/cpu-freq/>.

	  If in doubt, say N.
endif

if SPARC64
config SPARC_US3_CPUFREQ
	tristate "UltraSPARC-III CPU Frequency driver"
	help
	  This adds the CPUFreq driver for UltraSPARC-III processors.

	  For details, take a look at <file:Documentation/cpu-freq>.

	  If in doubt, say N.

config SPARC_US2E_CPUFREQ
	tristate "UltraSPARC-IIe CPU Frequency driver"
	help
	  This adds the CPUFreq driver for UltraSPARC-IIe processors.

	  For details, take a look at <file:Documentation/cpu-freq>.

	  If in doubt, say N.
endif

if SUPERH
config SH_CPU_FREQ
	tristate "SuperH CPU Frequency driver"
	help
	  This adds the cpufreq driver for SuperH. Any CPU that supports
	  clock rate rounding through the clock framework can use this
	  driver. While it will make the kernel slightly larger, this is
	  harmless for CPUs that don't support rate rounding. The driver
	  will also generate a notice in the boot log before disabling
	  itself if the CPU in question is not capable of rate rounding.

	  For details, take a look at <file:Documentation/cpu-freq>.

	  If unsure, say N.
endif

config QORIQ_CPUFREQ
	tristate "CPU frequency scaling driver for Freescale QorIQ SoCs"
	depends on OF && COMMON_CLK && (PPC_E500MC || ARM)
	depends on !CPU_THERMAL || THERMAL
	select CLK_QORIQ
	help
	  This adds the CPUFreq driver support for Freescale QorIQ SoCs
	  which are capable of changing the CPU's frequency dynamically.

endif
endmenu
Commit	Line	Data
	1	menu "CPU Frequency scaling"
	2
	3	config 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
	19	if CPU_FREQ
	20
	21	config CPU_FREQ_GOV_COMMON
	22	select IRQ_WORK
	23	bool
	24
	25	config CPU_FREQ_BOOST_SW
	26	bool
	27	depends on THERMAL
	28
	29	config CPU_FREQ_STAT
	30	tristate "CPU frequency translation statistics"
	31	default y
	32	help
	33	This driver exports CPU frequency statistics information through sysfs
	34	file system.
	35
	36	To compile this driver as a module, choose M here: the
	37	module will be called cpufreq_stats.
	38
	39	If in doubt, say N.
	40
	41	config CPU_FREQ_STAT_DETAILS
	42	bool "CPU frequency translation statistics details"
	43	depends on CPU_FREQ_STAT
	44	help
	45	This will show detail CPU frequency translation table in sysfs file
	46	system.
	47
	48	If in doubt, say N.
	49
	50	choice
	51	prompt "Default CPUFreq governor"
	52	default CPU_FREQ_DEFAULT_GOV_USERSPACE if ARM_SA1100_CPUFREQ \|\| ARM_SA1110_CPUFREQ
	53	default CPU_FREQ_DEFAULT_GOV_PERFORMANCE
	54	help
	55	This option sets which CPUFreq governor shall be loaded at
	56	startup. If in doubt, select 'performance'.
	57
	58	config CPU_FREQ_DEFAULT_GOV_PERFORMANCE
	59	bool "performance"
	60	select CPU_FREQ_GOV_PERFORMANCE
	61	help
	62	Use the CPUFreq governor 'performance' as default. This sets
	63	the frequency statically to the highest frequency supported by
	64	the CPU.
	65
	66	config CPU_FREQ_DEFAULT_GOV_POWERSAVE
	67	bool "powersave"
	68	select CPU_FREQ_GOV_POWERSAVE
	69	help
	70	Use the CPUFreq governor 'powersave' as default. This sets
	71	the frequency statically to the lowest frequency supported by
	72	the CPU.
	73
	74	config CPU_FREQ_DEFAULT_GOV_USERSPACE
	75	bool "userspace"
	76	select CPU_FREQ_GOV_USERSPACE
	77	help
	78	Use the CPUFreq governor 'userspace' as default. This allows
	79	you to set the CPU frequency manually or when a userspace
	80	program shall be able to set the CPU dynamically without having
	81	to enable the userspace governor manually.
	82
	83	config CPU_FREQ_DEFAULT_GOV_ONDEMAND
	84	bool "ondemand"
	85	select CPU_FREQ_GOV_ONDEMAND
	86	select CPU_FREQ_GOV_PERFORMANCE
	87	help
	88	Use the CPUFreq governor 'ondemand' as default. This allows
	89	you to get a full dynamic frequency capable system by simply
	90	loading your cpufreq low-level hardware driver.
	91	Be aware that not all cpufreq drivers support the ondemand
	92	governor. If unsure have a look at the help section of the
	93	driver. Fallback governor will be the performance governor.
	94
	95	config CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
	96	bool "conservative"
	97	select CPU_FREQ_GOV_CONSERVATIVE
	98	select CPU_FREQ_GOV_PERFORMANCE
	99	help
	100	Use the CPUFreq governor 'conservative' as default. This allows
	101	you to get a full dynamic frequency capable system by simply
	102	loading your cpufreq low-level hardware driver.
	103	Be aware that not all cpufreq drivers support the conservative
	104	governor. If unsure have a look at the help section of the
	105	driver. Fallback governor will be the performance governor.
	106	endchoice
	107
	108	config CPU_FREQ_GOV_PERFORMANCE
	109	tristate "'performance' governor"
	110	help
	111	This cpufreq governor sets the frequency statically to the
	112	highest available CPU frequency.
	113
	114	To compile this driver as a module, choose M here: the
	115	module will be called cpufreq_performance.
	116
	117	If in doubt, say Y.
	118
	119	config CPU_FREQ_GOV_POWERSAVE
	120	tristate "'powersave' governor"
	121	help
	122	This cpufreq governor sets the frequency statically to the
	123	lowest available CPU frequency.
	124
	125	To compile this driver as a module, choose M here: the
	126	module will be called cpufreq_powersave.
	127
	128	If in doubt, say Y.
	129
	130	config CPU_FREQ_GOV_USERSPACE
	131	tristate "'userspace' governor for userspace frequency scaling"
	132	help
	133	Enable this cpufreq governor when you either want to set the
	134	CPU frequency manually or when a userspace program shall
	135	be able to set the CPU dynamically, like on LART
	136	<http://www.lartmaker.nl/>.
	137
	138	To compile this driver as a module, choose M here: the
	139	module will be called cpufreq_userspace.
	140
	141	For details, take a look at <file:Documentation/cpu-freq/>.
	142
	143	If in doubt, say Y.
	144
	145	config CPU_FREQ_GOV_ONDEMAND
	146	tristate "'ondemand' cpufreq policy governor"
	147	select CPU_FREQ_GOV_COMMON
	148	help
	149	'ondemand' - This driver adds a dynamic cpufreq policy governor.
	150	The governor does a periodic polling and
	151	changes frequency based on the CPU utilization.
	152	The support for this governor depends on CPU capability to
	153	do fast frequency switching (i.e, very low latency frequency
	154	transitions).
	155
	156	To compile this driver as a module, choose M here: the
	157	module will be called cpufreq_ondemand.
	158
	159	For details, take a look at linux/Documentation/cpu-freq.
	160
	161	If in doubt, say N.
	162
	163	config CPU_FREQ_GOV_CONSERVATIVE
	164	tristate "'conservative' cpufreq governor"
	165	depends on CPU_FREQ
	166	select CPU_FREQ_GOV_COMMON
	167	help
	168	'conservative' - this driver is rather similar to the 'ondemand'
	169	governor both in its source code and its purpose, the difference is
	170	its optimisation for better suitability in a battery powered
	171	environment. The frequency is gracefully increased and decreased
	172	rather than jumping to 100% when speed is required.
	173
	174	If you have a desktop machine then you should really be considering
	175	the 'ondemand' governor instead, however if you are using a laptop,
	176	PDA or even an AMD64 based computer (due to the unacceptable
	177	step-by-step latency issues between the minimum and maximum frequency
	178	transitions in the CPU) you will probably want to use this governor.
	179
	180	To compile this driver as a module, choose M here: the
	181	module will be called cpufreq_conservative.
	182
	183	For details, take a look at linux/Documentation/cpu-freq.
	184
	185	If in doubt, say N.
	186
	187	comment "CPU frequency scaling drivers"
	188
	189	config CPUFREQ_DT
	190	tristate "Generic DT based cpufreq driver"
	191	depends on HAVE_CLK && OF
	192	# if CPU_THERMAL is on and THERMAL=m, CPUFREQ_DT cannot be =y:
	193	depends on !CPU_THERMAL \|\| THERMAL
	194	select PM_OPP
	195	help
	196	This adds a generic DT based cpufreq driver for frequency management.
	197	It supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
	198	systems which share clock and voltage across all CPUs.
	199
	200	If in doubt, say N.
	201
	202	if X86
	203	source "drivers/cpufreq/Kconfig.x86"
	204	endif
	205
	206	if ARM \|\| ARM64
	207	source "drivers/cpufreq/Kconfig.arm"
	208	endif
	209
	210	if PPC32 \|\| PPC64
	211	source "drivers/cpufreq/Kconfig.powerpc"
	212	endif
	213
	214	if AVR32
	215	config AVR32_AT32AP_CPUFREQ
	216	bool "CPU frequency driver for AT32AP"
	217	depends on PLATFORM_AT32AP
	218	default n
	219	help
	220	This enables the CPU frequency driver for AT32AP processors.
	221	If in doubt, say N.
	222	endif
	223
	224	if IA64
	225	config IA64_ACPI_CPUFREQ
	226	tristate "ACPI Processor P-States driver"
	227	depends on ACPI_PROCESSOR
	228	help
	229	This driver adds a CPUFreq driver which utilizes the ACPI
	230	Processor Performance States.
	231
	232	For details, take a look at <file:Documentation/cpu-freq/>.
	233
	234	If in doubt, say N.
	235	endif
	236
	237	if MIPS
	238	config LOONGSON2_CPUFREQ
	239	tristate "Loongson2 CPUFreq Driver"
	240	help
	241	This option adds a CPUFreq driver for loongson processors which
	242	support software configurable cpu frequency.
	243
	244	Loongson2F and it's successors support this feature.
	245
	246	For details, take a look at <file:Documentation/cpu-freq/>.
	247
	248	If in doubt, say N.
	249
	250	config LOONGSON1_CPUFREQ
	251	tristate "Loongson1 CPUFreq Driver"
	252	help
	253	This option adds a CPUFreq driver for loongson1 processors which
	254	support software configurable cpu frequency.
	255
	256	For details, take a look at <file:Documentation/cpu-freq/>.
	257
	258	If in doubt, say N.
	259	endif
	260
	261	if SPARC64
	262	config SPARC_US3_CPUFREQ
	263	tristate "UltraSPARC-III CPU Frequency driver"
	264	help
	265	This adds the CPUFreq driver for UltraSPARC-III processors.
	266
	267	For details, take a look at <file:Documentation/cpu-freq>.
	268
	269	If in doubt, say N.
	270
	271	config SPARC_US2E_CPUFREQ
	272	tristate "UltraSPARC-IIe CPU Frequency driver"
	273	help
	274	This adds the CPUFreq driver for UltraSPARC-IIe processors.
	275
	276	For details, take a look at <file:Documentation/cpu-freq>.
	277
	278	If in doubt, say N.
	279	endif
	280
	281	if SUPERH
	282	config SH_CPU_FREQ
	283	tristate "SuperH CPU Frequency driver"
	284	help
	285	This adds the cpufreq driver for SuperH. Any CPU that supports
	286	clock rate rounding through the clock framework can use this
	287	driver. While it will make the kernel slightly larger, this is
	288	harmless for CPUs that don't support rate rounding. The driver
	289	will also generate a notice in the boot log before disabling
	290	itself if the CPU in question is not capable of rate rounding.
	291
	292	For details, take a look at <file:Documentation/cpu-freq>.
	293
	294	If unsure, say N.
	295	endif
	296
	297	config QORIQ_CPUFREQ
	298	tristate "CPU frequency scaling driver for Freescale QorIQ SoCs"
	299	depends on OF && COMMON_CLK && (PPC_E500MC \|\| ARM)
	300	depends on !CPU_THERMAL \|\| THERMAL
	301	select CLK_QORIQ
	302	help
	303	This adds the CPUFreq driver support for Freescale QorIQ SoCs
	304	which are capable of changing the CPU's frequency dynamically.
	305
	306	endif
	307	endmenu