[PATCH 01/14] media: h264: Add a more generic reflist builder init

[Paul Kocialkowski <paulk@sys-base.io>]

This should become part of a larger reflist builder rework.

Signed-off-by: Paul Kocialkowski <paulk@sys-base.io>
---
 drivers/media/v4l2-core/v4l2-h264.c | 69 +++++++++++++++++++++++++++++
 include/media/v4l2-h264.h           |  7 +++
 2 files changed, 76 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-h264.c b/drivers/media/v4l2-core/v4l2-h264.c
index c00197d095e7..4e5a177ca2c7 100644
--- a/drivers/media/v4l2-core/v4l2-h264.c
+++ b/drivers/media/v4l2-core/v4l2-h264.c
@@ -105,6 +105,75 @@ v4l2_h264_init_reflist_builder(struct v4l2_h264_reflist_builder *b,
 }
 EXPORT_SYMBOL_GPL(v4l2_h264_init_reflist_builder);
 
+void
+v4l2_h264_init_reflist_builder_gen(struct v4l2_h264_reflist_builder *b,
+		const struct v4l2_ctrl_h264_sps *sps,
+		const struct v4l2_h264_dpb_entry dpb[V4L2_H264_NUM_DPB_ENTRIES],
+		unsigned int pic_order_count, unsigned int frame_num, unsigned int fields)
+{
+	int cur_frame_num, max_frame_num;
+	unsigned int i;
+
+	max_frame_num = 1 << (sps->log2_max_frame_num_minus4 + 4);
+	cur_frame_num = frame_num;
+
+	memset(b, 0, sizeof(*b));
+	b->cur_pic_order_count = pic_order_count;
+	b->cur_pic_fields = fields;
+
+	for (i = 0; i < V4L2_H264_NUM_DPB_ENTRIES; i++) {
+		if (!(dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE))
+			continue;
+
+		if (dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM)
+			b->refs[i].longterm = true;
+
+		/*
+		 * Handle frame_num wraparound as described in section
+		 * '8.2.4.1 Decoding process for picture numbers' of the spec.
+		 * For long term references, frame_num is set to
+		 * long_term_frame_idx which requires no wrapping.
+		 */
+		if (!b->refs[i].longterm && dpb[i].frame_num > cur_frame_num)
+			b->refs[i].frame_num = (int)dpb[i].frame_num -
+					       max_frame_num;
+		else
+			b->refs[i].frame_num = dpb[i].frame_num;
+
+		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;
+
+		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_gen);
+
 static s32 v4l2_h264_get_poc(const struct v4l2_h264_reflist_builder *b,
 			     const struct v4l2_h264_reference *ref)
 {
diff --git a/include/media/v4l2-h264.h b/include/media/v4l2-h264.h
index 0d9eaa956123..1833c0556963 100644
--- a/include/media/v4l2-h264.h
+++ b/include/media/v4l2-h264.h
@@ -42,6 +42,7 @@ struct v4l2_h264_reflist_builder {
 	u8 cur_pic_fields;
 
 	struct v4l2_h264_reference unordered_reflist[V4L2_H264_REF_LIST_LEN];
+	/* FIXME: confusing with valid flag (active is checked). Proper terminology is "used" */
 	u8 num_valid;
 };
 
@@ -51,6 +52,12 @@ v4l2_h264_init_reflist_builder(struct v4l2_h264_reflist_builder *b,
 		const struct v4l2_ctrl_h264_sps *sps,
 		const struct v4l2_h264_dpb_entry dpb[V4L2_H264_NUM_DPB_ENTRIES]);
 
+void
+v4l2_h264_init_reflist_builder_gen(struct v4l2_h264_reflist_builder *b,
+		const struct v4l2_ctrl_h264_sps *sps,
+		const struct v4l2_h264_dpb_entry dpb[V4L2_H264_NUM_DPB_ENTRIES],
+		unsigned int pic_order_count, unsigned int frame_num, unsigned int fields);
+
 /**
  * v4l2_h264_build_b_ref_lists() - Build the B0/B1 reference lists
  *
-- 
2.53.0