tree 4f713a464f066752b8f190fafe1d23bc37118d59
parent 77873887729aaddec5cd27203a6ce8c4987733e4
author Dirk Brandewie <dirk.j.brandewie@intel.com> 1415295647 -0800
committer Rafael J. Wysocki <rafael.j.wysocki@intel.com> 1415747078 +0100

intel_pstate: Add support for HWP

Add support of Hardware Managed Performance States (HWP) described in Volume 3
section 14.4 of the SDM.

With HWP enbaled intel_pstate will no longer be responsible for selecting P
states for the processor. intel_pstate will continue to register to
the cpufreq core as the scaling driver for CPUs implementing
HWP. In HWP mode intel_pstate provides three functions reporting
frequency to the cpufreq core, support for the set_policy() interface
from the core and maintaining the intel_pstate sysfs interface in
/sys/devices/system/cpu/intel_pstate.  User preferences expressed via
the set_policy() interface or the sysfs interface are forwared to the
CPU via the HWP MSR interface.

Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>