[QUESTION] drm/meson: Hardware cursor plane for Amlogic/meson

[Jian-Hong Pan]

We have a khadas VIM2 board equipped with Amlogic S912 chip. We found
it shows multiple cursors at the same screen which is more like
afterimages. This bug is filed as the ticket [1] and exists until X
uses software cursor with the commit ("modesetting: Disable
pageflipping when using a swcursor") [2]. Meson drm does not support
hardware cursors and current versions of X will disable pageflipping
when using software cursor, which is a big performance hit.

We also learned there is the hardware cursor plane supported by
Amlogic chips from the slide "Mainline Linux on AmLogic SoCs" [3]. Is
it possible to have the hardware cursor available over the drm
interface?

[1] https://gitlab.freedesktop.org/mesa/mesa/-/issues/3143
[2] https://gitlab.freedesktop.org/xorg/xserver/-/commit/0aaac8d783e78c040a70a55ba8d67809abd7e625
[3] https://people.freedesktop.org/~narmstrong/lca2018-amlogic/#/section

Thanks,
Jian-Hong Pan