@@ -252,8 +252,6 @@ static void rcar_du_crtc_update_planes(struct rcar_du_crtc *rcrtc)
* with superposition controller 2.
*/
if (rcrtc->index % 2) {
- u32 value = rcar_du_group_read(rcrtc->group, DPTSR);
-
/* The DPTSR register is updated when the display controller is
* stopped. We thus need to restart the DU. Once again, sorry
* for the flicker. One way to mitigate the issue would be to
@@ -261,11 +259,13 @@ static void rcar_du_crtc_update_planes(struct rcar_du_crtc *rcrtc)
* split, or through a module parameter). Flicker would then
* occur only if we need to break the pre-association.
*/
- if (value != dptsr) {
+ mutex_lock(&rcrtc->group->planes.lock);
+ if (rcar_du_group_read(rcrtc->group, DPTSR) != dptsr) {
rcar_du_group_write(rcrtc->group, DPTSR, dptsr);
if (rcrtc->group->used_crtcs)
rcar_du_group_restart(rcrtc->group);
}
+ mutex_unlock(&rcrtc->group->planes.lock);
}
rcar_du_group_write(rcrtc->group, rcrtc->index % 2 ? DS2PR : DS1PR,
@@ -435,9 +435,7 @@ void rcar_du_crtc_resume(struct rcar_du_crtc *rcrtc)
rcar_du_plane_setup(plane);
}
- mutex_lock(&rcrtc->group->planes.lock);
rcar_du_crtc_update_planes(rcrtc);
- mutex_unlock(&rcrtc->group->planes.lock);
}
/* -----------------------------------------------------------------------------
@@ -501,9 +499,7 @@ static void rcar_du_crtc_atomic_flush(struct drm_crtc *crtc)
{
struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
- mutex_lock(&rcrtc->group->planes.lock);
rcar_du_crtc_update_planes(rcrtc);
- mutex_unlock(&rcrtc->group->planes.lock);
}
static const struct drm_crtc_helper_funcs crtc_helper_funcs = {
Only the planes to CRTCs association control register DPTSR needs to be protected by custom locking, don't hold the mutex around the whole code. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> --- drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-)