At least MediaTek platforms are able to get the GPU clocks and regulators
completely off during system suspend, allowing to save a bit of power.
Panfrost is used on more than just MediaTek SoCs and the benefits of this
can be variable across different SoC models and/or different SoCs from
different manufacturers: this means that just adding this ability for all
could result in unexpected issues and breakages on untested SoCs.
For the aforemenetioned reasons, turning off the clocks and/or regulators
was implemented inside of a capabilities barrier that shall be enabled on
a per-SoC basis (in the panfrost_compatible platform data) after testing
of both benefits and feasibility.
In this series, I am adding the ability to switch on/off clocks and
regulators and enabling that on all MediaTek platforms, as I was able
to successfully test that on multiple Chromebooks featuring different
MediaTek SoCs; specifically, I've manually tested on MT8186, MT8192 and
MT8195, while MT8183 got tested only by KernelCI.
Cheers!
AngeloGioacchino Del Regno (4):
drm/panfrost: Implement ability to turn on/off GPU clocks in suspend
drm/panfrost: Set clocks on/off during system sleep on MediaTek SoCs
drm/panfrost: Implement ability to turn on/off regulators in suspend
drm/panfrost: Set regulators on/off during system sleep on MediaTek
SoCs
drivers/gpu/drm/panfrost/panfrost_device.c | 78 ++++++++++++++++++++--
drivers/gpu/drm/panfrost/panfrost_device.h | 13 ++++
drivers/gpu/drm/panfrost/panfrost_drv.c | 3 +
3 files changed, 90 insertions(+), 4 deletions(-)
--
2.42.0
