thermal: introduce the Power Allocator governor
authorJavi Merino <javi.merino@arm.com>
Mon, 2 Mar 2015 17:17:19 +0000 (17:17 +0000)
committerEduardo Valentin <edubezval@gmail.com>
Tue, 5 May 2015 04:27:52 +0000 (21:27 -0700)
commit6b775e870c56c59c3e16531ea2307b797395f9f7
tree40cceadc9fd3cfc6f30efe8b90db92c703ea7e00
parentc36cf07176316fbe6a4bdbc23afcb0cbf7822bf2
thermal: introduce the Power Allocator governor

The power allocator governor is a thermal governor that controls system
and device power allocation to control temperature.  Conceptually, the
implementation divides the sustainable power of a thermal zone among
all the heat sources in that zone.

This governor relies on "power actors", entities that represent heat
sources.  They can report current and maximum power consumption and
can set a given maximum power consumption, usually via a cooling
device.

The governor uses a Proportional Integral Derivative (PID) controller
driven by the temperature of the thermal zone.  The output of the
controller is a power budget that is then allocated to each power
actor that can have bearing on the temperature we are trying to
control.  It decides how much power to give each cooling device based
on the performance they are requesting.  The PID controller ensures
that the total power budget does not exceed the control temperature.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Documentation/thermal/power_allocator.txt [new file with mode: 0644]
drivers/thermal/Kconfig
drivers/thermal/Makefile
drivers/thermal/power_allocator.c [new file with mode: 0644]
drivers/thermal/thermal_core.c
drivers/thermal/thermal_core.h
include/linux/thermal.h