Re: [PATCH v8 22/24] drm: rockchip: Add VOP2 driver

[Daniel Stone <daniel@fooishbar.org>]

Hi Andy,

On Tue, 15 Mar 2022 at 06:46, Andy Yan <andy.yan@rock-chips.com> wrote:
> On 3/11/22 16:33, Sascha Hauer wrote:
> > The driver is tested with HDMI and MIPI-DSI display on a RK3568-EVB
> > board. Overlay support is tested with the modetest utility. AFBC support
> > on the cluster windows is tested with weston-simple-dmabuf-egl on
> > weston using the (yet to be upstreamed) panfrost driver support.
>
> Do we need some modification to test AFBC by weston-simple-dma-egl ?
>
> I have a buildroot system with weston-10.0.9 and mesa 21.3.5.
>
> After launch weston, I run weston-simple-dmabuf-egl, but from the output
>
> of sys/kernel/debug/dri/0/state, the weston is still use Smart0-win0,
> which is
>
> a non-AFBC window.
>
> Do i need to modify the vop2 driver to set one Cluster window as primary
> plane?

Are you using the open-source Panfrost driver, or the proprietary Arm
DDK? The DDK was previously using some non-standard modifier tokens
which have since been corrected upstream.

You can see from running `weston-debug drm-backend` (if you start
Weston with `--debug`) the output as it tries to put client surfaces
on to overlay planes, and why it can or cannot.

For Weston's own composited output (used when it cannot place client
surfaces on to planes), it will just use whatever the KMS driver
declares as the primary plane. Weston does not have any logic to say
'oh, this plane is AFBC and AFBC is better, so I will use this as my
primary plane': we just follow what the kernel tells us.

Cheers,
Daniel