Missing mali regulator in Amlogic dts

[Martin Blumenstingl]

Hi Heiner,

On Tue, Mar 8, 2022 at 7:24 PM Heiner Kallweit <hkallweit1 at gmail.com> wrote:
>
> I get following error on a  S905W-based system.
> lima d00c0000.gpu: dev_pm_opp_set_regulators: no regulator (mali) found: -19
This warning is harmless (see below)

> I see mali-supply in the DTS of few other vendors, but in no Amlogic DTS.
> Is it missing, or are Amlogic SoCs different here?
As far as I understand, on GXBB and GXL SoCs the VDDEE regulator is
managed by the firmware (which is unfortunately closed-source).
IIRC on the hardware side VDDEE is just another PWM regulator, just
like with the 32-bit SoCs or with G12A (and later) SoCs.

> In the latter case supposedly drivers/gpu/drm/lima/lima_devfreq.c would
> have to be changed to check for the optional regulator and not call
> devm_pm_opp_set_regulators() if it's missing.
I think I just copied the logic from panfrost
(drivers/gpu/drm/panfrost/panfrost_devfreq.c) to lima.
So GXM boards (using panfrost) will probably report a similar warning.
That said, I don't know enough to judge whether your approach makes sense.


Best regards,
Martin