On 14/04/2024 15:52, Jagadeesh Kona wrote:
On 4/14/2024 6:09 PM, Bryan O'Donoghue wrote:
On 13/04/2024 16:20, Jagadeesh Kona wrote:
The Venus driver requires vcodec GDSC to be ON in SW mode for clock
operations and move it back to HW mode to gain power benefits. Earlier,
as there is no interface to switch the GDSC mode from GenPD framework,
the GDSC is moved to HW control mode as part of GDSC enable callback and
venus driver is writing to its POWER_CONTROL register to keep the
GDSC ON
from SW whereever required. But the POWER_CONTROL register addresses
are not constant and can vary across the variants.
Also as per the HW recommendation, the GDSC mode switching needs to be
controlled from respective GDSC register and this is a uniform approach
across all the targets. Hence use dev_pm_genpd_set_hwmode() API which
controls GDSC mode switching using its respective GDSC register.
In venus V6 variants, the vcodec gdsc gets enabled in SW mode by default
with new HW_CTRL_TRIGGER flag and there is no need to switch it to SW
mode again after enable, hence add check to avoid switching gdsc to
SW mode
again after gdsc enable. Similarly add check to avoid switching GDSC
to HW
mode before disabling the GDSC, so GDSC gets enabled in SW mode in
the next
enable.
Signed-off-by: Jagadeesh Kona <quic_jkona@xxxxxxxxxxx>
Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx>
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When I tested this out on sm8250 a few months ago it was broken.
I don't quite see in your commit logs, how the breakage was addressed.
Can you provide some details ?
Thanks Bryan for your review!
In earlier series, venus driver is switching the vcodec GDSC to HW
control mode before disabling the GDSC by invoking
vcodec_control_v4(..., false) in poweroff_coreid(). Due to this, the
subsequent GDSC enable from venus driver is failing while polling for
GDSC power ON status, since GDSC is under HW control mode and HW can
keep the GDSC in disabled state.
Now a check is added in poweroff_coreid() to avoid switching the GDSC to
HW control mode before disabling the GDSC for Venus V6 variants that use
this new API. Hence during the next GDSC enable, GDSC will be in SW mode
and GDSC will powerup properly.
Right so the intention is to have HW GDSC control during playback only -
and then revert to SW control when no stream is active, right ?
I tried your series on today's -next.
Here is -next without your changes
https://drive.google.com/file/d/1PFuLOlEp582rBQUvuwc9PNZUBxn1ioYf/view?usp=sharing
and here is -next with your changes
https://drive.google.com/file/d/1PHR4rZnWUH9Wp2B-itT5yCUXIMOMZrwM/view?usp=sharing
The first time I tried that test the stopping/stuttering was worse.
So yes the original crash was fixed but, this looks like a performance
regression to me.
Here's the tree I tested with.
https://git.codelinaro.org/bryan.odonoghue/kernel/-/tree/linux-next-24-05-23-review?ref_type=heads
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bod
