drivers/cpufreq/Kconfig.x86 - linux - Git at Google

 #
 # x86 CPU Frequency scaling drivers
 #

 config X86_INTEL_PSTATE
        bool "Intel P state control"
        depends on X86
        help
           This driver provides a P state for Intel core processors.
 	  The driver implements an internal governor and will become
           the scaling driver and governor for Sandy bridge processors.

 	  When this driver is enabled it will become the perferred
           scaling driver for Sandy bridge processors.

 	  If in doubt, say N.

 config X86_PCC_CPUFREQ
 	tristate "Processor Clocking Control interface driver"
 	depends on ACPI && ACPI_PROCESSOR
 	help
 	  This driver adds support for the PCC interface.

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

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

 	  If in doubt, say N.

 config X86_ACPI_CPUFREQ
 	tristate "ACPI Processor P-States driver"
 	select CPU_FREQ_TABLE
 	depends on ACPI_PROCESSOR
 	help
 	  This driver adds a CPUFreq driver which utilizes the ACPI
 	  Processor Performance States.
 	  This driver also supports Intel Enhanced Speedstep and newer
 	  AMD CPUs.

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

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

 	  If in doubt, say N.

 config X86_ACPI_CPUFREQ_CPB
 	default y
 	bool "Legacy cpb sysfs knob support for AMD CPUs"
 	depends on X86_ACPI_CPUFREQ && CPU_SUP_AMD
 	help
 	  The powernow-k8 driver used to provide a sysfs knob called "cpb"
 	  to disable the Core Performance Boosting feature of AMD CPUs. This
 	  file has now been superseeded by the more generic "boost" entry.

 	  By enabling this option the acpi_cpufreq driver provides the old
 	  entry in addition to the new boost ones, for compatibility reasons.

 config ELAN_CPUFREQ
 	tristate "AMD Elan SC400 and SC410"
 	select CPU_FREQ_TABLE
 	depends on MELAN
 	---help---
 	  This adds the CPUFreq driver for AMD Elan SC400 and SC410
 	  processors.

 	  You need to specify the processor maximum speed as boot
 	  parameter: elanfreq=maxspeed (in kHz) or as module
 	  parameter "max_freq".

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

 	  If in doubt, say N.

 config SC520_CPUFREQ
 	tristate "AMD Elan SC520"
 	select CPU_FREQ_TABLE
 	depends on MELAN
 	---help---
 	  This adds the CPUFreq driver for AMD Elan SC520 processor.

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

 	  If in doubt, say N.


 config X86_POWERNOW_K6
 	tristate "AMD Mobile K6-2/K6-3 PowerNow!"
 	select CPU_FREQ_TABLE
 	depends on X86_32
 	help
 	  This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
 	  AMD K6-3+ processors.

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

 	  If in doubt, say N.

 config X86_POWERNOW_K7
 	tristate "AMD Mobile Athlon/Duron PowerNow!"
 	select CPU_FREQ_TABLE
 	depends on X86_32
 	help
 	  This adds the CPUFreq driver for mobile AMD K7 mobile processors.

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

 	  If in doubt, say N.

 config X86_POWERNOW_K7_ACPI
 	bool
 	depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
 	depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
 	depends on X86_32
 	default y

 config X86_POWERNOW_K8
 	tristate "AMD Opteron/Athlon64 PowerNow!"
 	select CPU_FREQ_TABLE
 	depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
 	help
 	  This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
 	  Support for K10 and newer processors is now in acpi-cpufreq.

 	  To compile this driver as a module, choose M here: the
 	  module will be called powernow-k8.

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

 config X86_GX_SUSPMOD
 	tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
 	depends on X86_32 && PCI
 	help
 	 This add the CPUFreq driver for NatSemi Geode processors which
 	 support suspend modulation.

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

 	 If in doubt, say N.

 config X86_SPEEDSTEP_CENTRINO
 	tristate "Intel Enhanced SpeedStep (deprecated)"
 	select CPU_FREQ_TABLE
 	select X86_SPEEDSTEP_CENTRINO_TABLE if X86_32
 	depends on X86_32 || (X86_64 && ACPI_PROCESSOR)
 	help
 	  This is deprecated and this functionality is now merged into
 	  acpi_cpufreq (X86_ACPI_CPUFREQ). Use that driver instead of
 	  speedstep_centrino.
 	  This adds the CPUFreq driver for Enhanced SpeedStep enabled
 	  mobile CPUs.  This means Intel Pentium M (Centrino) CPUs
 	  or 64bit enabled Intel Xeons.

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

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

 	  If in doubt, say N.

 config X86_SPEEDSTEP_CENTRINO_TABLE
 	bool "Built-in tables for Banias CPUs"
 	depends on X86_32 && X86_SPEEDSTEP_CENTRINO
 	default y
 	help
 	  Use built-in tables for Banias CPUs if ACPI encoding
 	  is not available.

 	  If in doubt, say N.

 config X86_SPEEDSTEP_ICH
 	tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
 	select CPU_FREQ_TABLE
 	depends on X86_32
 	help
 	  This adds the CPUFreq driver for certain mobile Intel Pentium III
 	  (Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
 	  mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
 	  ICH3 or ICH4 southbridge.

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

 	  If in doubt, say N.

 config X86_SPEEDSTEP_SMI
 	tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
 	select CPU_FREQ_TABLE
 	depends on X86_32 && EXPERIMENTAL
 	help
 	  This adds the CPUFreq driver for certain mobile Intel Pentium III
 	  (Coppermine), all mobile Intel Pentium III-M (Tualatin)
 	  on systems which have an Intel 440BX/ZX/MX southbridge.

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

 	  If in doubt, say N.

 config X86_P4_CLOCKMOD
 	tristate "Intel Pentium 4 clock modulation"
 	select CPU_FREQ_TABLE
 	help
 	  This adds the CPUFreq driver for Intel Pentium 4 / XEON
 	  processors.  When enabled it will lower CPU temperature by skipping
 	  clocks.

 	  This driver should be only used in exceptional
 	  circumstances when very low power is needed because it causes severe
 	  slowdowns and noticeable latencies.  Normally Speedstep should be used
 	  instead.

 	  To compile this driver as a module, choose M here: the
 	  module will be called p4-clockmod.

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

 	  Unless you are absolutely sure say N.

 config X86_CPUFREQ_NFORCE2
 	tristate "nVidia nForce2 FSB changing"
 	depends on X86_32 && EXPERIMENTAL
 	help
 	  This adds the CPUFreq driver for FSB changing on nVidia nForce2
 	  platforms.

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

 	  If in doubt, say N.

 config X86_LONGRUN
 	tristate "Transmeta LongRun"
 	depends on X86_32
 	help
 	  This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
 	  which support LongRun.

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

 	  If in doubt, say N.

 config X86_LONGHAUL
 	tristate "VIA Cyrix III Longhaul"
 	select CPU_FREQ_TABLE
 	depends on X86_32 && ACPI_PROCESSOR
 	help
 	  This adds the CPUFreq driver for VIA Samuel/CyrixIII,
 	  VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
 	  processors.

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

 	  If in doubt, say N.

 config X86_E_POWERSAVER
 	tristate "VIA C7 Enhanced PowerSaver (DANGEROUS)"
 	select CPU_FREQ_TABLE
 	depends on X86_32 && EXPERIMENTAL
 	help
 	  This adds the CPUFreq driver for VIA C7 processors.  However, this driver
 	  does not have any safeguards to prevent operating the CPU out of spec
 	  and is thus considered dangerous.  Please use the regular ACPI cpufreq
 	  driver, enabled by CONFIG_X86_ACPI_CPUFREQ.

 	  If in doubt, say N.

 comment "shared options"

 config X86_SPEEDSTEP_LIB
 	tristate
 	default (X86_SPEEDSTEP_ICH || X86_SPEEDSTEP_SMI || X86_P4_CLOCKMOD)

 config X86_SPEEDSTEP_RELAXED_CAP_CHECK
 	bool "Relaxed speedstep capability checks"
 	depends on X86_32 && (X86_SPEEDSTEP_SMI || X86_SPEEDSTEP_ICH)
 	help
 	  Don't perform all checks for a speedstep capable system which would
 	  normally be done. Some ancient or strange systems, though speedstep
 	  capable, don't always indicate that they are speedstep capable. This
 	  option lets the probing code bypass some of those checks if the
 	  parameter "relaxed_check=1" is passed to the module.
	#
	# x86 CPU Frequency scaling drivers
	#

	config X86_INTEL_PSTATE
	bool "Intel P state control"
	depends on X86
	help
	This driver provides a P state for Intel core processors.
	The driver implements an internal governor and will become
	the scaling driver and governor for Sandy bridge processors.

	When this driver is enabled it will become the perferred
	scaling driver for Sandy bridge processors.

	If in doubt, say N.

	config X86_PCC_CPUFREQ
	tristate "Processor Clocking Control interface driver"
	depends on ACPI && ACPI_PROCESSOR
	help
	This driver adds support for the PCC interface.

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

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

	If in doubt, say N.

	config X86_ACPI_CPUFREQ
	tristate "ACPI Processor P-States driver"
	select CPU_FREQ_TABLE
	depends on ACPI_PROCESSOR
	help
	This driver adds a CPUFreq driver which utilizes the ACPI
	Processor Performance States.
	This driver also supports Intel Enhanced Speedstep and newer
	AMD CPUs.

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

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

	If in doubt, say N.

	config X86_ACPI_CPUFREQ_CPB
	default y
	bool "Legacy cpb sysfs knob support for AMD CPUs"
	depends on X86_ACPI_CPUFREQ && CPU_SUP_AMD
	help
	The powernow-k8 driver used to provide a sysfs knob called "cpb"
	to disable the Core Performance Boosting feature of AMD CPUs. This
	file has now been superseeded by the more generic "boost" entry.

	By enabling this option the acpi_cpufreq driver provides the old
	entry in addition to the new boost ones, for compatibility reasons.

	config ELAN_CPUFREQ
	tristate "AMD Elan SC400 and SC410"
	select CPU_FREQ_TABLE
	depends on MELAN
	---help---
	This adds the CPUFreq driver for AMD Elan SC400 and SC410
	processors.

	You need to specify the processor maximum speed as boot
	parameter: elanfreq=maxspeed (in kHz) or as module
	parameter "max_freq".

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

	If in doubt, say N.

	config SC520_CPUFREQ
	tristate "AMD Elan SC520"
	select CPU_FREQ_TABLE
	depends on MELAN
	---help---
	This adds the CPUFreq driver for AMD Elan SC520 processor.

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

	If in doubt, say N.


	config X86_POWERNOW_K6
	tristate "AMD Mobile K6-2/K6-3 PowerNow!"
	select CPU_FREQ_TABLE
	depends on X86_32
	help
	This adds the CPUFreq driver for mobile AMD K6-2+ and mobile
	AMD K6-3+ processors.

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

	If in doubt, say N.

	config X86_POWERNOW_K7
	tristate "AMD Mobile Athlon/Duron PowerNow!"
	select CPU_FREQ_TABLE
	depends on X86_32
	help
	This adds the CPUFreq driver for mobile AMD K7 mobile processors.

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

	If in doubt, say N.

	config X86_POWERNOW_K7_ACPI
	bool
	depends on X86_POWERNOW_K7 && ACPI_PROCESSOR
	depends on !(X86_POWERNOW_K7 = y && ACPI_PROCESSOR = m)
	depends on X86_32
	default y

	config X86_POWERNOW_K8
	tristate "AMD Opteron/Athlon64 PowerNow!"
	select CPU_FREQ_TABLE
	depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ
	help
	This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors.
	Support for K10 and newer processors is now in acpi-cpufreq.

	To compile this driver as a module, choose M here: the
	module will be called powernow-k8.

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

	config X86_GX_SUSPMOD
	tristate "Cyrix MediaGX/NatSemi Geode Suspend Modulation"
	depends on X86_32 && PCI
	help
	This add the CPUFreq driver for NatSemi Geode processors which
	support suspend modulation.

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

	If in doubt, say N.

	config X86_SPEEDSTEP_CENTRINO
	tristate "Intel Enhanced SpeedStep (deprecated)"
	select CPU_FREQ_TABLE
	select X86_SPEEDSTEP_CENTRINO_TABLE if X86_32
	depends on X86_32 \|\| (X86_64 && ACPI_PROCESSOR)
	help
	This is deprecated and this functionality is now merged into
	acpi_cpufreq (X86_ACPI_CPUFREQ). Use that driver instead of
	speedstep_centrino.
	This adds the CPUFreq driver for Enhanced SpeedStep enabled
	mobile CPUs. This means Intel Pentium M (Centrino) CPUs
	or 64bit enabled Intel Xeons.

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

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

	If in doubt, say N.

	config X86_SPEEDSTEP_CENTRINO_TABLE
	bool "Built-in tables for Banias CPUs"
	depends on X86_32 && X86_SPEEDSTEP_CENTRINO
	default y
	help
	Use built-in tables for Banias CPUs if ACPI encoding
	is not available.

	If in doubt, say N.

	config X86_SPEEDSTEP_ICH
	tristate "Intel Speedstep on ICH-M chipsets (ioport interface)"
	select CPU_FREQ_TABLE
	depends on X86_32
	help
	This adds the CPUFreq driver for certain mobile Intel Pentium III
	(Coppermine), all mobile Intel Pentium III-M (Tualatin) and all
	mobile Intel Pentium 4 P4-M on systems which have an Intel ICH2,
	ICH3 or ICH4 southbridge.

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

	If in doubt, say N.

	config X86_SPEEDSTEP_SMI
	tristate "Intel SpeedStep on 440BX/ZX/MX chipsets (SMI interface)"
	select CPU_FREQ_TABLE
	depends on X86_32 && EXPERIMENTAL
	help
	This adds the CPUFreq driver for certain mobile Intel Pentium III
	(Coppermine), all mobile Intel Pentium III-M (Tualatin)
	on systems which have an Intel 440BX/ZX/MX southbridge.

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

	If in doubt, say N.

	config X86_P4_CLOCKMOD
	tristate "Intel Pentium 4 clock modulation"
	select CPU_FREQ_TABLE
	help
	This adds the CPUFreq driver for Intel Pentium 4 / XEON
	processors. When enabled it will lower CPU temperature by skipping
	clocks.

	This driver should be only used in exceptional
	circumstances when very low power is needed because it causes severe
	slowdowns and noticeable latencies. Normally Speedstep should be used
	instead.

	To compile this driver as a module, choose M here: the
	module will be called p4-clockmod.

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

	Unless you are absolutely sure say N.

	config X86_CPUFREQ_NFORCE2
	tristate "nVidia nForce2 FSB changing"
	depends on X86_32 && EXPERIMENTAL
	help
	This adds the CPUFreq driver for FSB changing on nVidia nForce2
	platforms.

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

	If in doubt, say N.

	config X86_LONGRUN
	tristate "Transmeta LongRun"
	depends on X86_32
	help
	This adds the CPUFreq driver for Transmeta Crusoe and Efficeon processors
	which support LongRun.

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

	If in doubt, say N.

	config X86_LONGHAUL
	tristate "VIA Cyrix III Longhaul"
	select CPU_FREQ_TABLE
	depends on X86_32 && ACPI_PROCESSOR
	help
	This adds the CPUFreq driver for VIA Samuel/CyrixIII,
	VIA Cyrix Samuel/C3, VIA Cyrix Ezra and VIA Cyrix Ezra-T
	processors.

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

	If in doubt, say N.

	config X86_E_POWERSAVER
	tristate "VIA C7 Enhanced PowerSaver (DANGEROUS)"
	select CPU_FREQ_TABLE
	depends on X86_32 && EXPERIMENTAL
	help
	This adds the CPUFreq driver for VIA C7 processors. However, this driver
	does not have any safeguards to prevent operating the CPU out of spec
	and is thus considered dangerous. Please use the regular ACPI cpufreq
	driver, enabled by CONFIG_X86_ACPI_CPUFREQ.

	If in doubt, say N.

	comment "shared options"

	config X86_SPEEDSTEP_LIB
	tristate
	default (X86_SPEEDSTEP_ICH \|\| X86_SPEEDSTEP_SMI \|\| X86_P4_CLOCKMOD)

	config X86_SPEEDSTEP_RELAXED_CAP_CHECK
	bool "Relaxed speedstep capability checks"
	depends on X86_32 && (X86_SPEEDSTEP_SMI \|\| X86_SPEEDSTEP_ICH)
	help
	Don't perform all checks for a speedstep capable system which would
	normally be done. Some ancient or strange systems, though speedstep
	capable, don't always indicate that they are speedstep capable. This
	option lets the probing code bypass some of those checks if the
	parameter "relaxed_check=1" is passed to the module.