Re: drm warning with mainline due to 467e30171b5b ("drm/vc4: hdmi: Move HDMI reset to pm_resume")

From: Sudip Mukherjee
Date: Thu Aug 18 2022 - 16:37:17 EST


On Wed, Aug 17, 2022 at 8:10 AM Maxime Ripard <maxime@xxxxxxxxxx> wrote:
>
> Hi,
>
> On Tue, Aug 16, 2022 at 05:34:51PM +0100, Sudip Mukherjee (Codethink) wrote:
> > Not sure if it has been reported but the mainline kernel shows a drm warning
> > on RPI4B.
> >
> > [ 14.821276] WARNING: CPU: 3 PID: 187 at drivers/gpu/drm/vc4/vc4_hdmi_regs.h:487 vc5_hdmi_reset+0x1f8/0x240 [vc4]

<snip>

> >
> > git bisect pointed to 467e30171b5b ("drm/vc4: hdmi: Move HDMI reset to pm_resume")
> > and reverting this commit has fixed the warning.
> >
> > I will be happy to test any patch or provide any extra log if needed.
>
> We have fixes for this in drm-misc-next that have missed the cut for the
> merge window:
>
> https://lore.kernel.org/all/20220629123510.1915022-38-maxime@xxxxxxxxxx/
> https://lore.kernel.org/all/20220629123510.1915022-39-maxime@xxxxxxxxxx/
>
> If it fixes it for you, I'll apply it to drm-misc-fixes

Thanks. With these two patches applied on top of the latest mainline,
I don't see the warning anymore.

Tested-by: Sudip Mukherjee <sudip.mukherjee@xxxxxxxxxxxxxxx>


--
Regards
Sudip