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HWPSTATE_INTEL(4)	     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 perfor-
     mance states on Intel platforms, also known as Intel Speed  Shift	Technol-
     ogy.

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 pref-
	     erence  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.in-
     tel.com/content/www/us/en/processors/architectures-software-developer-manu-
     als.html.

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

FreeBSD ports 15.1		 April 21, 2020 	       HWPSTATE_INTEL(4)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=hwpstate_intel&manpath=FreeBSD+15.1-RELEASE+and+Ports>

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