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@xxxxxxxxxxxxxxxx> --- drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c index 29bbb44eecc9..8459aaee8add 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c @@ -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 = { -- 2.0.5 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel