media: h264: Store all fields into the unordered list

When the current picture is a field, store each field into the
unordered_list and preserve both top and bottom picture order
count.

Signed-off-by: Nicolas Dufresne <[e-mail]>
Reviewed-by: Sebastian Fricke <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/platform/nvidia/tegra-vde/h264.c

···
 		if (err)
 			return err;
 
-		if (b.refs[dpb_idx].pic_order_count < b.cur_pic_order_count)
+		if (b.refs[dpb_idx].top_field_order_cnt < b.cur_pic_order_count)
 			h264->dpb_ref_frames_with_earlier_poc_nb++;
 	}
 

drivers/media/v4l2-core/v4l2-h264.c

···
 	}
 
 	for (i = 0; i < V4L2_H264_NUM_DPB_ENTRIES; i++) {
-		u32 pic_order_count;
-
 		if (!(dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE))
 			continue;
 
···
 		/*
 		 * Handle frame_num wraparound as described in section
 		 * '8.2.4.1 Decoding process for picture numbers' of the spec.
-		 * TODO: This logic will have to be adjusted when we start
-		 * supporting interlaced content.
 		 * For long term references, frame_num is set to
 		 * long_term_frame_idx which requires no wrapping.
 		 */
···
 		else
 			b->refs[i].frame_num = dpb[i].frame_num;
 
-		if (dpb[i].fields == V4L2_H264_FRAME_REF)
-			pic_order_count = min(dpb[i].top_field_order_cnt,
-					      dpb[i].bottom_field_order_cnt);
-		else if (dpb[i].fields & V4L2_H264_BOTTOM_FIELD_REF)
-			pic_order_count = dpb[i].bottom_field_order_cnt;
-		else
-			pic_order_count = dpb[i].top_field_order_cnt;
+		b->refs[i].top_field_order_cnt = dpb[i].top_field_order_cnt;
+		b->refs[i].bottom_field_order_cnt = dpb[i].bottom_field_order_cnt;
 
-		b->refs[i].pic_order_count = pic_order_count;
-		b->unordered_reflist[b->num_valid].index = i;
-		b->num_valid++;
+		if (b->cur_pic_fields == V4L2_H264_FRAME_REF) {
+			u8 fields = V4L2_H264_FRAME_REF;
+
+			b->unordered_reflist[b->num_valid].index = i;
+			b->unordered_reflist[b->num_valid].fields = fields;
+			b->num_valid++;
+			continue;
+		}
+
+		if (dpb[i].fields & V4L2_H264_TOP_FIELD_REF) {
+			u8 fields = V4L2_H264_TOP_FIELD_REF;
+
+			b->unordered_reflist[b->num_valid].index = i;
+			b->unordered_reflist[b->num_valid].fields = fields;
+			b->num_valid++;
+		}
+
+		if (dpb[i].fields & V4L2_H264_BOTTOM_FIELD_REF) {
+			u8 fields = V4L2_H264_BOTTOM_FIELD_REF;
+
+			b->unordered_reflist[b->num_valid].index = i;
+			b->unordered_reflist[b->num_valid].fields = fields;
+			b->num_valid++;
+		}
 	}
 
 	for (i = b->num_valid; i < ARRAY_SIZE(b->unordered_reflist); i++)
 		b->unordered_reflist[i].index = i;
 }
 EXPORT_SYMBOL_GPL(v4l2_h264_init_reflist_builder);
+
+static s32 v4l2_h264_get_poc(const struct v4l2_h264_reflist_builder *b,
+			     const struct v4l2_h264_reference *ref)
+{
+	switch (ref->fields) {
+	case V4L2_H264_FRAME_REF:
+		return min(b->refs[ref->index].top_field_order_cnt,
+				b->refs[ref->index].bottom_field_order_cnt);
+	case V4L2_H264_TOP_FIELD_REF:
+		return b->refs[ref->index].top_field_order_cnt;
+	case V4L2_H264_BOTTOM_FIELD_REF:
+		return b->refs[ref->index].bottom_field_order_cnt;
+	}
+
+	/* not reached */
+	return 0;
+}
 
 static int v4l2_h264_p_ref_list_cmp(const void *ptra, const void *ptrb,
 				    const void *data)
···
 		       builder->refs[idxb].pic_num ?
 		       -1 : 1;
 
-	poca = builder->refs[idxa].pic_order_count;
-	pocb = builder->refs[idxb].pic_order_count;
+	poca = v4l2_h264_get_poc(builder, ptra);
+	pocb = v4l2_h264_get_poc(builder, ptrb);
 
 	/*
 	 * Short term pics with POC < cur POC first in POC descending order
···
 		       builder->refs[idxb].pic_num ?
 		       -1 : 1;
 
-	poca = builder->refs[idxa].pic_order_count;
-	pocb = builder->refs[idxb].pic_order_count;
+	poca = v4l2_h264_get_poc(builder, ptra);
+	pocb = v4l2_h264_get_poc(builder, ptrb);
 
 	/*
 	 * Short term pics with POC > cur POC first in POC ascending order

include/media/v4l2-h264.h

···
 /**
  * struct v4l2_h264_reflist_builder - Reference list builder object
  *
- * @refs.pic_order_count: reference picture order count
+ * @refs.top_field_order_cnt: top field order count
+ * @refs.bottom_field_order_cnt: bottom field order count
  * @refs.frame_num: reference frame number
  * @refs.pic_num: reference picture number
  * @refs.longterm: set to true for a long term reference
···
  */
 struct v4l2_h264_reflist_builder {
 	struct {
-		s32 pic_order_count;
+		s32 top_field_order_cnt;
+		s32 bottom_field_order_cnt;
 		int frame_num;
 		u32 pic_num;
 		u16 longterm : 1;