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From:   cong yang <yangcong5@huaqin.corp-partner.google.com>
Date:   Wed, 28 Jun 2023 09:47:09 +0800
Message-ID: <CAHwB_NLDFqDEQ14cTAo3z1pvXvCZXhMeRbTXM3u93hVtpjE52w@mail.gmail.com>
Subject: Re: [v2] drm/panel: Fine tune Starry-ili9882t panel HFP and HBP
To:     Doug Anderson <dianders@google.com>
Cc:     sam@ravnborg.org, neil.armstrong@linaro.org, daniel@ffwll.ch,
        airlied@gmail.com, hsinyi@google.com,
        dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
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Hi, Doug


On Wed, Jun 28, 2023 at 5:17=E2=80=AFAM Doug Anderson <dianders@google.com>=
 wrote:
>
> Hi,
>
> On Mon, Jun 26, 2023 at 10:01=E2=80=AFPM Cong Yang
> <yangcong5@huaqin.corp-partner.google.com> 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 60H=
z
>
> 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@chromium.org>