drm: rcar-du: Split planes pre-association 4/4 between CRTCs

If we have more than one CRTCs in a group pre-associate planes 0-3 with
CRTC 0 and planes 4-7 with CRTC 1 to minimize flicker occurring when the
association is changed. The pre-association could be controlled by a
module parameter if needed.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
This commit is contained in:
Laurent Pinchart 2015-04-28 22:00:28 +03:00
parent fe6fbe9a02
commit 2610abfb3a
2 changed files with 4 additions and 6 deletions

View File

@ -257,9 +257,6 @@ static void rcar_du_crtc_update_planes(struct rcar_du_crtc *rcrtc)
* resulting in visible flicker. To mitigate the issue only update the
* association if needed by enabled planes. Planes being disabled will
* keep their current association.
*
* To mitigate the issue further we could pre-associate planes with
* CRTCs, either with a fixed 4/4 split, or through a module parameter.
*/
mutex_lock(&rcrtc->group->lock);

View File

@ -765,10 +765,11 @@ int rcar_du_modeset_init(struct rcar_du_device *rcdu)
rgrp->index = i;
rgrp->num_crtcs = min(rcdu->num_crtcs - 2 * i, 2U);
/* Pre-associate all hardware planes with the first CRTC in the
* group.
/* If we have more than one CRTCs in this group pre-associate
* planes 0-3 with CRTC 0 and planes 4-7 with CRTC 1 to minimize
* flicker occurring when the association is changed.
*/
rgrp->dptsr_planes = 0;
rgrp->dptsr_planes = rgrp->num_crtcs > 1 ? 0xf0 : 0;
ret = rcar_du_planes_init(rgrp);
if (ret < 0)