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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 performance 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 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)