diff options
| -rw-r--r-- | drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c index e6a32c4e4040..a40085806f5b 100644 --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c @@ -398,6 +398,19 @@ static void rcar_du_crtc_stop(struct rcar_du_crtc *rcrtc) if (!rcrtc->started) return; + /* Disable all planes and wait for the change to take effect. This is + * required as the DSnPR registers are updated on vblank, and no vblank + * will occur once the CRTC is stopped. Disabling planes when starting + * the CRTC thus wouldn't be enough as it would start scanning out + * immediately from old frame buffers until the next vblank. + * + * This increases the CRTC stop delay, especially when multiple CRTCs + * are stopped in one operation as we now wait for one vblank per CRTC. + * Whether this can be improved needs to be researched. + */ + rcar_du_group_write(rcrtc->group, rcrtc->index % 2 ? DS2PR : DS1PR, 0); + drm_crtc_wait_one_vblank(crtc); + /* Disable vertical blanking interrupt reporting. We first need to wait * for page flip completion before stopping the CRTC as userspace * expects page flips to eventually complete. |