Re: [PATCH v2 2/5] drm/mediatek: fix boot up for 720 and 480 but 1080

From: Chun-Kuang Hu
Date: Sun Aug 02 2020 - 19:41:56 EST

Hi, Frank:

Frank Wunderlich <frank-w@xxxxxxxxxxxxxxx> æ 2020å8æ2æ éæ äå12:44åéï
> Hi,
> Am 2. August 2020 02:08:44 MESZ schrieb Chun-Kuang Hu <>:
> >Hi, Frank:
> >> - disable tmds on phy on mt2701
> >> - support other resolutions like 1280x1024
> >
> >If this patch does two things, it should be broken into two patches.
> As far as i see,it only disable tmds and so fix specific resolutions like the the one below.some other (like 1080p) does not have this Problem.

OK, this is one thing, "disable tmds on phy on mt2701 to support other
resolutions like 1280x1024"

> > I think every pll is default off, so you should turn on pll rather
> > than disable tmds
> Is disabling tmds wrong here? Which pll is needed here? What does tmds? I got only the Patches for testing....

I don't know how does this pll and tmds work. I think you and me are
both not familiar with this hdmi phy. I agree this modification could
fix some problem, but does this patch have side effect which trigger
another problem? I need some reasonable description so I could have
confidence on this patch. tmds is a function in mt2701 but you disable
it. This mean you disable some function of this hardware. Why mt2701
does not need it?


> >> without this Patch i see flickering on my TFT (1280x1024),
> >> so i guess clock is wrong.
> regards Frank