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

[Jason-JH Lin (林睿祥)]

On Tue, 2024-10-01 at 08:55 +0000, CK Hu (胡俊光) wrote:
> Hi, Jason:
> 
> Would you clarify this problem?
> 

OK~

> Regards,
> CK
> 
> On Mon, 2024-09-30 at 12:48 -0500, Adam Thiede wrote:
> >  	 
> > External email : Please do not click links or open attachments
> > until you have verified the sender or the content.
> >  On 6/19/24 11:38, Hsiao Chien Sung via B4 Relay wrote:
> > > From: Hsiao Chien Sung <shawn.sung at mediatek.com>
> > > 
> > > Set the plane alpha according to DRM plane property.
> > > 
> > > Reviewed-by: CK Hu <ck.hu at mediatek.com>
> > > Reviewed-by: AngeloGioacchino Del Regno <
> > > angelogioacchino.delregno at collabora.com>
> > > Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek
> > > SoC MT8173.")
> > > Signed-off-by: Hsiao Chien Sung <shawn.sung at mediatek.com>
> > > ---
> > >   drivers/gpu/drm/mediatek/mtk_disp_ovl.c | 6 ++++--
> > >   1 file changed, 4 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> > > b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> > > index 943db4f1bd6b..4b370bc0746d 100644
> > > --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> > > +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
> > > @@ -458,8 +458,10 @@ void mtk_ovl_layer_config(struct device
> > > *dev, unsigned int idx,
> > >   }
> > >   
> > >   con = ovl_fmt_convert(ovl, fmt);
> > > -if (state->base.fb && state->base.fb->format->has_alpha)
> > > -con |= OVL_CON_AEN | OVL_CON_ALPHA;
> > > +if (state->base.fb) {
> > > +con |= OVL_CON_AEN;
> > > +con |= state->base.alpha & OVL_CON_ALPHA;

Hi Adam,

Could you print out the "fmt", "state->base.fb->format-
>has_alpha", "state->base.alpha" and "con" here?

pr_info("fmt:0x%x, has_alpha:0x%x, alpha:0x%x, con:0x%x \n",
        fmt, state->base.fb->format->has_alpha,
        state->base.alpha, con);

I'm not sure if it's the color format setting problem, maybe there is
something wire configuration here, such as XRGB8888 with alpha or
ARGB8888 without alpha.

So I want these information to compare with my MT8188. Thanks!

Regards,
Jason-JH.Lin

> > > +}
> > >   
> > >   /* CONST_BLD must be enabled for XRGB formats although the
> > > alpha channel
> > >    * can be ignored, or OVL will still read the value from
> > > memory.
> > > 
> > 
> > Hello, I believe that this commit has caused a problem for my
> > Lenovo 
> > C330 Chromebook running postmarketOS.
> > 
> > With kernel 6.11 this device didn't show any text on the tty or
> > splash 
> > screen during booting, but graphical environments (wayland, xorg)
> > do 
> > appear. With a few bisects I found it to be this commit. With it 
> > reverted I'm able to get text on the tty again.
> > 
> > The kernel config is here: 
> > 
https://gitlab.com/adamthiede/pmaports/-/tree/mt8173-611/device/community/linux-postmarketos-mediatek-mt8173/
> > To be perfectly clear, this device is not running Chrome OS.
> > 
> > I'm still rather new at this so it's also likely I got something
> > wrong 
> > or have a bad configuration option. If there is any more
> > information I 
> > can provide please let me know. Thank you.
> > 
> > - Adam Thiede