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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 per-
       formance	states on Intel	platforms, also	known  as  Intel  Speed	 Shift
       Technology.

LOADER TUNABLES
       hint.hwpstate_intel.0.disabled
	       Can  be used to disable hwpstate_intel, allowing	other compati-
	       ble drivers to manage performance  states,  like	 est(4).   De-
	       faults 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"  se-
	       lects 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 regard-
	       ing a preference	towards	performance (at	value 0), energy effi-
	       ciency (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	13.2			April 21, 2020		     HWPSTATE_INTEL(4)

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

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=hwpstate_intel&manpath=FreeBSD+14.0-RELEASE+and+Ports>

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