[PATCH v3 16/24] media: rkvdec: h264: Validate and use pic width and height in mbs

[Nicolas Dufresne]

From: Jonas Karlman <jonas@xxxxxxxxx>

The width and height in macroblocks is currently configured based on OUTPUT
buffer resolution, this works for frame pictures but can cause issues for
field pictures.

When frame_mbs_only_flag is 0 the height in mbs should be height of
the field instead of height of frame.

Validate pic_width_in_mbs_minus1 and pic_height_in_map_units_minus1
against OUTPUT buffer resolution and use these values to configure HW.
The validation is happening in both try_ctrt() and start() since it is
otherwise possible to trick the driver during initialization by changing
the OUTPUT format after having set a valid control.

Signed-off-by: Jonas Karlman <jonas@xxxxxxxxx>
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@xxxxxxxxxxxxx>
---
 drivers/staging/media/rkvdec/rkvdec-h264.c | 78 ++++++++++++++++------
 1 file changed, 59 insertions(+), 19 deletions(-)

diff --git a/drivers/staging/media/rkvdec/rkvdec-h264.c b/drivers/staging/media/rkvdec/rkvdec-h264.c
index 0dcbcb1bac80..f081b476340f 100644
--- a/drivers/staging/media/rkvdec/rkvdec-h264.c
+++ b/drivers/staging/media/rkvdec/rkvdec-h264.c
@@ -672,8 +672,16 @@ static void assemble_hw_pps(struct rkvdec_ctx *ctx,
 		  LOG2_MAX_PIC_ORDER_CNT_LSB_MINUS4);
 	WRITE_PPS(!!(sps->flags & V4L2_H264_SPS_FLAG_DELTA_PIC_ORDER_ALWAYS_ZERO),
 		  DELTA_PIC_ORDER_ALWAYS_ZERO_FLAG);
-	WRITE_PPS(DIV_ROUND_UP(ctx->coded_fmt.fmt.pix_mp.width, 16), PIC_WIDTH_IN_MBS);
-	WRITE_PPS(DIV_ROUND_UP(ctx->coded_fmt.fmt.pix_mp.height, 16), PIC_HEIGHT_IN_MBS);
+
+	/* Use the SPS values since they are already in macroblocks
+	 * dimensions, height can be field height (halved) if
+	 * V4L2_H264_SPS_FLAG_FRAME_MBS_ONLY is not set and also it allows
+	 * decoding smaller images into larger allocation which can be used
+	 * to implementing SVC spatial layer support.
+	 */
+	WRITE_PPS(sps->pic_width_in_mbs_minus1 + 1, PIC_WIDTH_IN_MBS);
+	WRITE_PPS(sps->pic_height_in_map_units_minus1 + 1, PIC_HEIGHT_IN_MBS);
+
 	WRITE_PPS(!!(sps->flags & V4L2_H264_SPS_FLAG_FRAME_MBS_ONLY),
 		  FRAME_MBS_ONLY_FLAG);
 	WRITE_PPS(!!(sps->flags & V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD),
@@ -1035,13 +1043,59 @@ static int rkvdec_h264_adjust_fmt(struct rkvdec_ctx *ctx,
 	return 0;
 }
 
+static int rkvdec_h264_validate_sps(struct rkvdec_ctx *ctx,
+				    const struct v4l2_ctrl_h264_sps *sps)
+{
+	unsigned int width, height;
+	/*
+	 * TODO: The hardware supports 10-bit and 4:2:2 profiles,
+	 * but it's currently broken in the driver.
+	 * Reject them for now, until it's fixed.
+	 */
+	if (sps->chroma_format_idc > 1)
+		/* Only 4:0:0 and 4:2:0 are supported */
+		return -EINVAL;
+	if (sps->bit_depth_luma_minus8 != sps->bit_depth_chroma_minus8)
+		/* Luma and chroma bit depth mismatch */
+		return -EINVAL;
+	if (sps->bit_depth_luma_minus8 != 0)
+		/* Only 8-bit is supported */
+		return -EINVAL;
+
+	width = (sps->pic_width_in_mbs_minus1 + 1) * 16;
+	height = (sps->pic_height_in_map_units_minus1 + 1) * 16;
+
+	/* when frame_mbs_only_flag is not set, this is field height,
+	 * which is half the final height (see (7-18) in the
+	 * specification)
+	 */
+	if (!(sps->flags & V4L2_H264_SPS_FLAG_FRAME_MBS_ONLY))
+		height *= 2;
+
+	if (width > ctx->coded_fmt.fmt.pix_mp.width ||
+	    height > ctx->coded_fmt.fmt.pix_mp.height)
+		return -EINVAL;
+
+	return 0;
+}
+
 static int rkvdec_h264_start(struct rkvdec_ctx *ctx)
 {
 	struct rkvdec_dev *rkvdec = ctx->dev;
 	struct rkvdec_h264_priv_tbl *priv_tbl;
 	struct rkvdec_h264_ctx *h264_ctx;
+	struct v4l2_ctrl *ctrl;
 	int ret;
 
+	ctrl = v4l2_ctrl_find(&ctx->ctrl_hdl,
+			      V4L2_CID_STATELESS_H264_SPS);
+	if (!ctrl)
+		return -EINVAL;
+
+	ret = rkvdec_h264_validate_sps(ctx, ctrl->p_new.p_h264_sps);
+	if (ret)
+		return ret;
+
 	h264_ctx = kzalloc(sizeof(*h264_ctx), GFP_KERNEL);
 	if (!h264_ctx)
 		return -ENOMEM;
@@ -1139,23 +1193,9 @@ static int rkvdec_h264_run(struct rkvdec_ctx *ctx)
 
 static int rkvdec_h264_try_ctrl(struct rkvdec_ctx *ctx, struct v4l2_ctrl *ctrl)
 {
-	if (ctrl->id == V4L2_CID_STATELESS_H264_SPS) {
-		const struct v4l2_ctrl_h264_sps *sps = ctrl->p_new.p_h264_sps;
-		/*
-		 * TODO: The hardware supports 10-bit and 4:2:2 profiles,
-		 * but it's currently broken in the driver.
-		 * Reject them for now, until it's fixed.
-		 */
-		if (sps->chroma_format_idc > 1)
-			/* Only 4:0:0 and 4:2:0 are supported */
-			return -EINVAL;
-		if (sps->bit_depth_luma_minus8 != sps->bit_depth_chroma_minus8)
-			/* Luma and chroma bit depth mismatch */
-			return -EINVAL;
-		if (sps->bit_depth_luma_minus8 != 0)
-			/* Only 8-bit is supported */
-			return -EINVAL;
-	}
+	if (ctrl->id == V4L2_CID_STATELESS_H264_SPS)
+		return rkvdec_h264_validate_sps(ctx, ctrl->p_new.p_h264_sps);
+
 	return 0;
 }
 
-- 
2.34.1