[PATCH 4.14 46/64] drm/vc4: Fix the "no scaling" case on multi-planar YUV formats

From: Greg Kroah-Hartman
Date: Thu Sep 27 2018 - 05:22:08 EST


4.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Boris Brezillon <boris.brezillon@xxxxxxxxxxx>

commit 658d8cbd07dae22ccecf49399e18c609c4e85c53 upstream.

When there's no scaling requested ->is_unity should be true no matter
the format.

Also, when no scaling is requested and we have a multi-planar YUV
format, we should leave ->y_scaling[0] to VC4_SCALING_NONE and only
set ->x_scaling[0] to VC4_SCALING_PPF.

Doing this fixes an hardly visible artifact (seen when using modetest
and a rather big overlay plane in YUV420).

Fixes: fc04023fafec ("drm/vc4: Add support for YUV planes.")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx>
Reviewed-by: Eric Anholt <eric@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20180725122907.13702-1-boris.brezillon@xxxxxxxxxxx
Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/vc4/vc4_plane.c | 25 ++++++++++++-------------
1 file changed, 12 insertions(+), 13 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_plane.c
+++ b/drivers/gpu/drm/vc4/vc4_plane.c
@@ -329,6 +329,9 @@ static int vc4_plane_setup_clipping_and_
vc4_state->y_scaling[0] = vc4_get_scaling_mode(vc4_state->src_h[0],
vc4_state->crtc_h);

+ vc4_state->is_unity = (vc4_state->x_scaling[0] == VC4_SCALING_NONE &&
+ vc4_state->y_scaling[0] == VC4_SCALING_NONE);
+
if (num_planes > 1) {
vc4_state->is_yuv = true;

@@ -344,24 +347,17 @@ static int vc4_plane_setup_clipping_and_
vc4_get_scaling_mode(vc4_state->src_h[1],
vc4_state->crtc_h);

- /* YUV conversion requires that scaling be enabled,
- * even on a plane that's otherwise 1:1. Choose TPZ
- * for simplicity.
+ /* YUV conversion requires that horizontal scaling be enabled,
+ * even on a plane that's otherwise 1:1. Looks like only PPF
+ * works in that case, so let's pick that one.
*/
- if (vc4_state->x_scaling[0] == VC4_SCALING_NONE)
- vc4_state->x_scaling[0] = VC4_SCALING_TPZ;
- if (vc4_state->y_scaling[0] == VC4_SCALING_NONE)
- vc4_state->y_scaling[0] = VC4_SCALING_TPZ;
+ if (vc4_state->is_unity)
+ vc4_state->x_scaling[0] = VC4_SCALING_PPF;
} else {
vc4_state->x_scaling[1] = VC4_SCALING_NONE;
vc4_state->y_scaling[1] = VC4_SCALING_NONE;
}

- vc4_state->is_unity = (vc4_state->x_scaling[0] == VC4_SCALING_NONE &&
- vc4_state->y_scaling[0] == VC4_SCALING_NONE &&
- vc4_state->x_scaling[1] == VC4_SCALING_NONE &&
- vc4_state->y_scaling[1] == VC4_SCALING_NONE);
-
/* No configuring scaling on the cursor plane, since it gets
non-vblank-synced updates, and scaling requires requires
LBM changes which have to be vblank-synced.
@@ -639,7 +635,10 @@ static int vc4_plane_mode_set(struct drm
vc4_dlist_write(vc4_state, SCALER_CSC2_ITR_R_601_5);
}

- if (!vc4_state->is_unity) {
+ if (vc4_state->x_scaling[0] != VC4_SCALING_NONE ||
+ vc4_state->x_scaling[1] != VC4_SCALING_NONE ||
+ vc4_state->y_scaling[0] != VC4_SCALING_NONE ||
+ vc4_state->y_scaling[1] != VC4_SCALING_NONE) {
/* LBM Base Address. */
if (vc4_state->y_scaling[0] != VC4_SCALING_NONE ||
vc4_state->y_scaling[1] != VC4_SCALING_NONE) {