Re: [v2] drm/panel: Fine tune Starry-ili9882t panel HFP and HBP

From: cong yang
Date: Tue Jun 27 2023 - 21:47:25 EST


Hi, Doug


On Wed, Jun 28, 2023 at 5:17 AM Doug Anderson <dianders@xxxxxxxxxx> wrote:
>
> Hi,
>
> On Mon, Jun 26, 2023 at 10:01 PM Cong Yang
> <yangcong5@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> >
> > Because the setting of hproch is too small, there will be warning in
> > kernel log[1]. After fine tune the HFP and HBP, this warning can be
> > solved. The actual measurement frame rate is 60.1Hz.
> >
> > [1]: WARNING kernel:[drm] HFP + HBP less than d-phy, FPS will under 60Hz
>
> Thanks for including the warming. This looks like something that's
> only printed on Mediatek display controllers. Just out of curiosity:
> is that because Mediatek controllers have special requirements, or is
> this something generic and the Mediatek controller is the only one
> that warns about it?

It seems to be a generic calculation formula for MTK controllers.
At least I have see this warning in both MT8186 and MT8188.
By the way, the same warning will also appear under coreboot.

>
>
> > Fixes: 8716a6473e6c ("drm/panel: Support for Starry-ili9882t TDDI
> > MIPI-DSI panel")
>
> Ideally the tool you have to send mail wouldn't wrap the Fixes line.
> Probably not worth resending just for this, but see if there's
> something you can do to fix this in the future.
>
> Since this is a tiny fix, I don't think we need to wait too long. I'll
> plan to land it on Thursday unless Neil wants to land it himself
> sooner.

Thank you, Doug.

>
> Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>