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

Message

Quentin Perret Feb. 4, 2019, 11:09 a.m. UTC

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=CV²f 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
   arm_big_little.
 - 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 ([e-mail])
 - Moved the OPP count inside dev_pm_opp_of_register_em() (Matthias,
   Sudeep)

Changes since v2 ([e-mail])
 - 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 ([e-mail]):
 - 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)

Thanks,
Quentin

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(-)

Comments

Viresh Kumar Feb. 5, 2019, 4:55 a.m. UTC | #1

On 04-02-19, 11:09, Quentin Perret wrote:
> 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=CV²f 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
>    arm_big_little.
>  - 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 ([e-mail])
>  - Moved the OPP count inside dev_pm_opp_of_register_em() (Matthias,
>    Sudeep)

Applied. Thanks.