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HWPSTATE_INTEL(4)      FreeBSD Kernel Interfaces Manual	     HWPSTATE_INTEL(4)

NAME
     hwpstate_intel -- Intel Speed Shift Technology driver

SYNOPSIS
     To	compile	this driver into your kernel place the following line in your
     kernel configuration file:

	   device cpufreq

DESCRIPTION
     The hwpstate_intel	driver provides	support	for hardware-controlled	per-
     formance states on	Intel platforms, also known as Intel Speed Shift Tech-
     nology.

LOADER TUNABLES
     hint.hwpstate_intel.0.disabled
	     Can be used to disable hwpstate_intel, allowing other compatible
	     drivers to	manage performance states, like	est(4).	 Defaults to
	     "0" (enabled).

     machdep.hwpstate_pkg_ctrl
	     Selects between package-level control (the	default) and per-core
	     control.  "1" selects package-level control and "0" selects core-
	     level control.

SYSCTL VARIABLES
     The following sysctl(8) values are	available

     dev.hwpstate_intel.%d.%desc
	     Describes the attached driver

     dev.hwpstate_intel.0.%desc: Intel Speed Shift

     dev.hwpstate_intel.%d.%driver
	     Driver in use, always hwpstate_intel.

     dev.hwpstate_intel.0.%driver: hwpstate_intel

     dev.hwpstate_intel.%d.%parent
	     The CPU that is exposing these frequencies.  For example cpu0.

     dev.hwpstate_intel.0.%parent: cpu0

     dev.hwpstate_intel.%d.epp
	     Energy/Performance	Preference.  Valid values range	from 0 to 100.
	     Setting this field	conveys	a hint to the hardware regarding a
	     preference	towards	performance (at	value 0), energy efficiency
	     (at value 100), or	somewhere in between.

     dev.hwpstate_intel.0.epp: 0

COMPATIBILITY
     hwpstate_intel is only found on supported Intel CPUs.

SEE ALSO
     cpufreq(4)

     Intel 64 and IA-32	Architectures Software Developer Manuals,
     http://www.intel.com/content/www/us/en/processors/architectures-software-
     developer-manuals.html.

AUTHORS
     This manual page was written by D Scott Phillips <scottph@FreeBSD.org>.

FreeBSD	13.0			April 21, 2020			  FreeBSD 13.0

NAME | SYNOPSIS | DESCRIPTION | LOADER TUNABLES | SYSCTL VARIABLES | COMPATIBILITY | SEE ALSO | AUTHORS

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