[PATCH] drm/mediatek: Add spinlock for setting vblank event in atomic_begin

[Fei Shao]

On Thu, Aug 31, 2023 at 3:12 PM Fei Shao <fshao at chromium.org> wrote:
>
> On Tue, Aug 22, 2023 at 10:27 PM Jason-JH.Lin <jason-jh.lin at mediatek.com> wrote:
> >
> > Add spinlock protection to avoid race condition on vblank event
> > between mtk_drm_crtc_atomic_begin() and mtk_drm_finish_page_flip().
> >
> > Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC MT8173.")
> > Signed-off-by: Jason-JH.Lin <jason-jh.lin at mediatek.com>
>
> Reviewed-by: Fei Shao <fshao at chromium.org>

Also, I verified that this fixes a real world system hang issue on the
MT8195 Chromebook.

Tested-by: Fei Shao <fshao at chromium.org>