Re: [PATCH] drm/pl111: Advertise no pixel blending

[Linus Walleij]

On Fri, Sep 11, 2026 at 3:24 PM Linus Walleij <linusw@xxxxxxxxxx> wrote:
> On Wed, Sep 9, 2026 at 10:16 AM Thomas Zimmermann <tzimmermann@xxxxxxx> wrote:
>
> > > The PL110/PL111 controller scans out a single framebuffer and does not
> > > blend its alpha channel with a background. Advertise
> > > DRM_MODE_BLEND_PIXEL_NONE to match the existing hardware behavior.
> >
> > Why does the driver report ARGB formats in the first place. I'm looking
> > at the code at [1] and I don't see any difference to XRGB. Unless I'm
> > missing something, please remove ARGB formats from this driver instead.
> > Drivers should not report formats they don't support.
>
> This should be the TRM for PL111:
> https://support.arm.com/documentation/ddi0293/c/?lang=en
>
> I checked it and indeed the ARGB* should be search/replaced with
> XRGB everywhere.
>
> Shall I propose a patch?
>
> I also have the actual hardware so I can test it properly.

Ah I see Roshan has already sent a patch (sorry for the confusion).

I will review/test that patch.

Yours,
Linus Walleij