[PATCH v4 0/4] Update Energy Model after chip binning adjusted voltages

Lukasz Luba lukasz.luba at arm.com
Tue Apr 2 08:58:18 PDT 2024


Hi all,

This is a follow-up patch aiming to add EM modification due to chip binning.
The first RFC and the discussion can be found here [1].

It uses Exynos chip driver code as a 1st user. The EM framework has been
extended to handle this use case easily, when the voltage has been changed
after setup. On my Odroid-xu4 in some OPPs I can observe ~20% power difference.
According to that data in driver tables it could be up to ~29%.

This chip binning is applicable to a lot of SoCs, so the EM framework should
make it easy to update. It uses the existing OPP and DT information to
re-calculate the new power values.

It has dependency on Exynos SoC driver tree.

Changes:
v4:
- added asterisk in the comment section (test robot)
- change the patch 2/4 header name and use 'Refactor'
v3:
- updated header description patch 2/4 (Dietmar)
- removed 2 sentences from comment and adjusted in patch 3/4 (Dietmar)
- patch 4/4 re-phrased code comment (Dietmar)
- collected tags (Krzysztof, Viresh)
v2:
- removed 'ret' from error message which wasn't initialized (Christian)
v1:
- exported the OPP calculation function from the OPP/OF so it can be
  used from EM fwk (Viresh)
- refactored EM updating function to re-use common code
- added new EM function which can be used by chip device drivers which
  modify the voltage in OPPs
RFC is at [1]

Regards,
Lukasz Luba

[1] https://lore.kernel.org/lkml/20231220110339.1065505-1-lukasz.luba@arm.com/

Lukasz Luba (4):
  OPP: OF: Export dev_opp_pm_calc_power() for usage from EM
  PM: EM: Refactor em_adjust_new_capacity()
  PM: EM: Add em_dev_update_chip_binning()
  soc: samsung: exynos-asv: Update Energy Model after adjusting voltage

 drivers/opp/of.c                 |  17 +++--
 drivers/soc/samsung/exynos-asv.c |  11 +++-
 include/linux/energy_model.h     |   5 ++
 include/linux/pm_opp.h           |   8 +++
 kernel/power/energy_model.c      | 106 +++++++++++++++++++++++++------
 5 files changed, 122 insertions(+), 25 deletions(-)

-- 
2.25.1




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