Re: [PATCH v2, 3/5] Revert "dt-bindings: mailbox: mtk-gce: fix incorrect mbox-cells value"

[Yongqiang Niu <yongqiang.niu@mediatek.com>]

On Wed, 2021-04-14 at 07:38 +0800, Chun-Kuang Hu wrote:
> Hi, Yongqiang:
> 
> Yongqiang Niu <yongqiang.niu@mediatek.com> 於 2021年4月12日 週一 下午7:19寫道：
> >
> > This reverts commit f83b03fc727ab56a77e68713d6e40299698f3c9f.
> >
> > Signed-off-by: Yongqiang Niu <yongqiang.niu@mediatek.com>
> > ---
> >  Documentation/devicetree/bindings/mailbox/mtk-gce.txt | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/Documentation/devicetree/bindings/mailbox/mtk-gce.txt b/Documentation/devicetree/bindings/mailbox/mtk-gce.txt
> > index 7771eca..cf48cd8 100644
> > --- a/Documentation/devicetree/bindings/mailbox/mtk-gce.txt
> > +++ b/Documentation/devicetree/bindings/mailbox/mtk-gce.txt
> > @@ -47,7 +47,7 @@ Example:
> >                 interrupts = <GIC_SPI 135 IRQ_TYPE_LEVEL_LOW>;
> >                 clocks = <&infracfg CLK_INFRA_GCE>;
> >                 clock-names = "gce";
> > -               #mbox-cells = <2>;
> > +               #mbox-cells = <3>;
> 
> I think we should not change the binding just to fix software bug.
> I think there are many temporary solution to fix drm bug. If drm bug
> is caused by cursor plane, you could temporarily let drm not support
> cursor plane to fix it (in [1], do not return DRM_PLANE_TYPE_CURSOR).
> But I would like you to find out the correct solution rather than a
> temporary solution because this bug is not so urgent. (For me, bug of
> build fail, boot fail, black screen is urgent).
> 
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/drm/mediatek/mtk_drm_crtc.c?h=v5.12-rc7#n699
> 
> Regards,
> Chun-Kuang.

this not drm bug, but caused by cmdq patch
https://patchwork.kernel.org/project/linux-mediatek/patch/20200214043325.16618-3-bibby.hsieh@mediatek.com/
before this patch, drm cursor and ui works well
after this patch, ui will flash when move cursor

this is critical issue,

> 
> >         };
> >
> >  Example for a client device:
> > --
> > 1.8.1.1.dirty
> >