Re: [PATCH v3 13/14] drm/mediatek: Support DRM plane alpha in OVL

[Yassine Oudjana]

On 03/10/2024 8:17 am, Jason-JH Lin (林睿祥) wrote:
> > Jason:
> > That is a lot of information, and quite above my head! Thank you
> > though.
> >
> > I should note that the log items I sent you are from the "good"
> > kernel -
> > 6.11 with the commit reverted. Here is a much longer set of logs:
> > https://termbin.com/co6v
> >
> > I've rebuild 6.11 with the log statement enabled and the "bad"
> > behavior.
> > Here is a dmesg from that: https://termbin.com/xiev
> Hi Adam,
>
> I think something wrong with your dmesg links, both logs look the same.
> We should see this log in the "bad" one:
> fmt:0x34325258, has_alpha:0x0, alpha:0xffff, con:0x2000
>
> But anyway, I think the reason for the downgrade is clear enough to me.
> So let's try to figure out the solution.
>
> > These logs are both from `dmesg`.
> >
> > I'm fairly certain I've built with the patch you referenced enabled.
> > The
> > kernels I run are just release kernels, not RCs or git branches or
> > anything. The mainline v6.11 kernel is the one that has this problem.
> > If
> > that patch has been merged into 6.11 (which, looks like it has) then
> > it's in the kernel I'm building.
>
> Got it.
> Then OVL_CONST_BLEND might be the unsupported configuration in MT8173,
> I think we should remove the XRGB8888 format for MT8173.
>
> Could you please try this modification and see if it'll change to use
> others supported format to show the text?
>
> --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> @@ -102,12 +102,9 @@ static inline bool is_10bit_rgb(u32 fmt)
>   }
>
>   static const u32 mt8173_formats[] = {
> -       DRM_FORMAT_XRGB8888,
>          DRM_FORMAT_ARGB8888,
> -       DRM_FORMAT_BGRX8888,
>          DRM_FORMAT_BGRA8888,
>          DRM_FORMAT_ABGR8888,
> -       DRM_FORMAT_XBGR8888,
>          DRM_FORMAT_RGB888,
>          DRM_FORMAT_BGR888,
>          DRM_FORMAT_RGB565,

This is what I get on MT6735:

[    1.729467] mediatek-drm mediatek-drm.1.auto: [drm] bpp/depth value 
of 32/24 not supported
[    1.737777] mediatek-drm mediatek-drm.1.auto: [drm] No compatible 
format found
[    1.745943] mediatek-drm mediatek-drm.1.auto: [drm] *ERROR* 
fbdev-dma: Failed to setup generic emulation (ret=-22)

> Regards,
> Jason-JH.Lin
>
> > - Adam Thiede