[PATCH v4 0/5] Register an Energy Model for Arm reference platforms

From: Quentin Perret
Date: Mon Feb 04 2019 - 06:10:02 EST

The Energy Model (EM) framework feeds interested subsystems (the
scheduler/EAS as of now) with power costs provided by drivers. Yet, no
driver is actually doing that upstream yet. This series updates a set of
CPUFreq drivers in order to register power costs in the EM framework for
some of the Arm reference platforms for EAS: Hikey960, Juno and TC2.

The series is split as follows:
- Patch 01 introduces in PM_OPP a helper function which estimates the
CPU power using the P=CVÂf equation also used by IPA. It should be
noted that this introduces duplicate code with IPA, which will
eventually be fixed by migrating IPA to using PM_EM. The ideal plan
would be to do so later, in a separate patch series. I would indeed
prefer to keep the thermal and CPUFreq discussion separate at this
stage, if deemed acceptable.
- Patches 02-04 make use of that PM_OPP helper function from the
following CPUFreq drivers: cpufreq-dt, scpi-cpufreq and
- Patch 05 modifies the SCMI cpufreq driver to pass the power costs
obtained from firmware to PM_EM. This patch is independent from the
rest of the series.

Changes since v3 (20190201093101.31869-1-quentin.perret@xxxxxxx)
- Moved the OPP count inside dev_pm_opp_of_register_em() (Matthias,

Changes since v2 (20190130170506.20450-1-quentin.perret@xxxxxxx)
- Added comment to explain why we check only the dynamic-power-coeff
property and not voltages in dev_pm_opp_of_register_em() (Viresh)
- Fixed comments/docstrings of new functions in opp/of.c (Matthias)
- Added Matthias' Tested-by to patch 01

Changes since v1 (20190128165522.31749-1-quentin.perret@xxxxxxx):
- Dropped the DT patches that have been queued by Sudeep
- Introduced dev_pm_opp_of_register_em() helper to check the presence
of the DT coeff before calling PM_EM (Viresh, Matthias)
- Coding-style improvements (Viresh, Matthias)


Dietmar Eggemann (1):
cpufreq: arm_big_little: Register an Energy Model

Quentin Perret (4):
PM / OPP: Introduce a power estimation helper
cpufreq: dt: Register an Energy Model
cpufreq: scpi: Register an Energy Model
cpufreq: scmi: Register an Energy Model

drivers/cpufreq/arm_big_little.c | 2 +
drivers/cpufreq/cpufreq-dt.c | 2 +
drivers/cpufreq/scmi-cpufreq.c | 39 ++++++++++++-
drivers/cpufreq/scpi-cpufreq.c | 3 +
drivers/opp/of.c | 99 ++++++++++++++++++++++++++++++++
include/linux/pm_opp.h | 6 ++
6 files changed, 148 insertions(+), 3 deletions(-)