[PATCH v2] drm/fourcc: add ARM GPU tile format

[Qiang Yu]

On Sun, Mar 10, 2019 at 10:53 AM Alyssa Rosenzweig <alyssa at rosenzweig.io> wrote:
>
> > If you think Midgard/Bifrost is compatible with AFBC and don't have it's
> > own format, and name "device" is improper,  I can rename
> > DRM_FORMAT_MOD_ARM_DEVICE_AFBC to DRM_FORMAT_MOD_ARM_TYPE_AFBC
> > DRM_FORMAT_MOD_ARM_DEVICE_GPU to DRM_FORMAT_MOD_ARM_TYPE_UTGARD
>
> That name is misleading, too. Midgard/Bifrost is compatible with *both*
> AFBC *and* tiled formats.

Then DRM_FORMAT_MOD_ARM_TYPE_GPU? I really don't know what's the
official name for this kind of format, so have to name it with the
device. Any better
suggestion?

>
> > Yes, lima need this when xserver/client share window buffer. Client may
> > render into a tiled window buffer to be presented to xserver, so need a
> > modifier to describe the buffer format. And Utgard can render into both
> > tiled and linear buffers.
>
> I see. I didn't realize Utgard could render into tiled formats; that's
> nice :)

Is tiled buffer rendering not reverse engineered yet or confirmed to be
not supported by Midgard/Bifrost?

Regards,
Qiang