@@ -22,6 +22,12 @@
#define POC_BUFFER_SIZE 34
#define SCALING_LIST_SIZE (6 * 16 + 2 * 64)
+/*
+ * For valid and long term reference marking, index are reversed, so bit 31
+ * indicates the status of the picture 0.
+ */
+#define REF_BIT(i) BIT(32 - 1 - (i))
+
/* Data structure describing auxiliary buffer format. */
struct hantro_h264_dec_priv_tbl {
u32 cabac_table[CABAC_INIT_BUFFER_SIZE];
@@ -227,6 +233,7 @@ static void prepare_table(struct hantro_ctx *ctx)
{
const struct hantro_h264_dec_ctrls *ctrls = &ctx->h264_dec.ctrls;
const struct v4l2_ctrl_h264_decode_params *dec_param = ctrls->decode;
+ const struct v4l2_ctrl_h264_sps *sps = ctrls->sps;
struct hantro_h264_dec_priv_tbl *tbl = ctx->h264_dec.priv.cpu;
const struct v4l2_h264_dpb_entry *dpb = ctx->h264_dec.dpb;
u32 dpb_longterm = 0;
@@ -237,20 +244,45 @@ static void prepare_table(struct hantro_ctx *ctx)
tbl->poc[i * 2] = dpb[i].top_field_order_cnt;
tbl->poc[i * 2 + 1] = dpb[i].bottom_field_order_cnt;
+ if (!(dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_VALID))
+ continue;
+
/*
* Set up bit maps of valid and long term DPBs.
- * NOTE: The bits are reversed, i.e. MSb is DPB 0.
+ * NOTE: The bits are reversed, i.e. MSb is DPB 0. For frame
+ * decoding, bit 31 to 15 are used, while for field decoding,
+ * all bits are used, with bit 31 being a top field, 30 a bottom
+ * field and so on.
*/
- if (dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE)
- dpb_valid |= BIT(HANTRO_H264_DPB_SIZE - 1 - i);
- if (dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM)
- dpb_longterm |= BIT(HANTRO_H264_DPB_SIZE - 1 - i);
+ if (dec_param->flags & V4L2_H264_DECODE_PARAM_FLAG_FIELD_PIC) {
+ if (dpb[i].fields & V4L2_H264_TOP_FIELD_REF)
+ dpb_valid |= REF_BIT(i * 2);
+
+ if (dpb[i].fields & V4L2_H264_BOTTOM_FIELD_REF)
+ dpb_valid |= REF_BIT(i * 2 + 1);
+
+ if (dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM) {
+ dpb_longterm |= REF_BIT(i * 2);
+ dpb_longterm |= REF_BIT(i * 2 + 1);
+ }
+ } else {
+ dpb_valid |= REF_BIT(i);
+
+ if (dpb[i].flags & V4L2_H264_DPB_ENTRY_FLAG_LONG_TERM)
+ dpb_longterm |= REF_BIT(i);
+ }
+ }
+ ctx->h264_dec.dpb_valid = dpb_valid;
+ ctx->h264_dec.dpb_longterm = dpb_longterm;
+
+ if ((dec_param->flags & V4L2_H264_DECODE_PARAM_FLAG_FIELD_PIC) ||
+ !(sps->flags & V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD)) {
+ tbl->poc[32] = ctx->h264_dec.cur_poc;
+ tbl->poc[33] = 0;
+ } else {
+ tbl->poc[32] = dec_param->top_field_order_cnt;
+ tbl->poc[33] = dec_param->bottom_field_order_cnt;
}
- ctx->h264_dec.dpb_valid = dpb_valid << 16;
- ctx->h264_dec.dpb_longterm = dpb_longterm << 16;
-
- tbl->poc[32] = dec_param->top_field_order_cnt;
- tbl->poc[33] = dec_param->bottom_field_order_cnt;
assemble_scaling_list(ctx);
}
@@ -326,6 +358,8 @@ dma_addr_t hantro_h264_get_ref_buf(struct hantro_ctx *ctx,
{
struct v4l2_h264_dpb_entry *dpb = ctx->h264_dec.dpb;
dma_addr_t dma_addr = 0;
+ s32 cur_poc = ctx->h264_dec.cur_poc;
+ u32 flags;
if (dpb[dpb_idx].flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE)
dma_addr = hantro_get_ref(ctx, dpb[dpb_idx].reference_ts);
@@ -343,7 +377,12 @@ dma_addr_t hantro_h264_get_ref_buf(struct hantro_ctx *ctx,
dma_addr = hantro_get_dec_buf_addr(ctx, buf);
}
- return dma_addr;
+ flags = dpb[dpb_idx].flags & V4L2_H264_DPB_ENTRY_FLAG_FIELD ? 0x2 : 0;
+ flags |= abs(dpb[dpb_idx].top_field_order_cnt - cur_poc) <
+ abs(dpb[dpb_idx].bottom_field_order_cnt - cur_poc) ?
+ 0x1 : 0;
+
+ return dma_addr | flags;
}
u16 hantro_h264_get_ref_nbr(struct hantro_ctx *ctx, unsigned int dpb_idx)
@@ -355,6 +394,47 @@ u16 hantro_h264_get_ref_nbr(struct hantro_ctx *ctx, unsigned int dpb_idx)
return dpb->frame_num;
}
+/*
+ * Removes all references with the same parity as the current picture from the
+ * reference list. The remaining list will have references with the opposite
+ * parity. This is effectively a deduplication of references since each buffer
+ * stores two fields. For this reason, each buffer is found twice in the
+ * reference list.
+ *
+ * This technique has been chosen through trial and error. This simple approach
+ * resulted in the highest conformance score. Note that this method may suffer
+ * worse quality in the case an opposite reference frame has been lost. If this
+ * becomes a problem in the future, it should be possible to add a preprocessing
+ * to identify un-paired fields and avoid removing them.
+ */
+static void deduplicate_reflist(struct v4l2_h264_reflist_builder *b,
+ struct v4l2_h264_reference *reflist)
+{
+ int write_idx = 0;
+ int i;
+
+ if (b->cur_pic_fields == V4L2_H264_FRAME_REF) {
+ write_idx = b->num_valid;
+ goto done;
+ }
+
+ for (i = 0; i < b->num_valid; i++) {
+ if (!(b->cur_pic_fields == reflist[i].fields)) {
+ reflist[write_idx++] = reflist[i];
+ continue;
+ }
+ }
+
+done:
+ /* Should not happen unless we have a bug in the reflist builder. */
+ if (WARN_ON(write_idx > 16))
+ write_idx = 16;
+
+ /* Clear the remaining, some streams fails otherwise */
+ for (; write_idx < 16; write_idx++)
+ reflist[write_idx].index = 15;
+}
+
int hantro_h264_dec_prepare_run(struct hantro_ctx *ctx)
{
struct hantro_h264_dec_hw_ctx *h264_ctx = &ctx->h264_dec;
@@ -386,15 +466,29 @@ int hantro_h264_dec_prepare_run(struct hantro_ctx *ctx)
/* Update the DPB with new refs. */
update_dpb(ctx);
- /* Prepare data in memory. */
- prepare_table(ctx);
-
/* Build the P/B{0,1} ref lists. */
v4l2_h264_init_reflist_builder(&reflist_builder, ctrls->decode,
ctrls->sps, ctx->h264_dec.dpb);
+ h264_ctx->cur_poc = reflist_builder.cur_pic_order_count;
+
+ /* Prepare data in memory. */
+ prepare_table(ctx);
+
v4l2_h264_build_p_ref_list(&reflist_builder, h264_ctx->reflists.p);
v4l2_h264_build_b_ref_lists(&reflist_builder, h264_ctx->reflists.b0,
h264_ctx->reflists.b1);
+
+ /*
+ * Reduce ref lists to at most 16 entries, Hantro hardware will deduce
+ * the actual picture lists in field through the dpb_valid,
+ * dpb_longterm bitmap along with the current frame parity.
+ */
+ if (reflist_builder.cur_pic_fields != V4L2_H264_FRAME_REF) {
+ deduplicate_reflist(&reflist_builder, h264_ctx->reflists.p);
+ deduplicate_reflist(&reflist_builder, h264_ctx->reflists.b0);
+ deduplicate_reflist(&reflist_builder, h264_ctx->reflists.b1);
+ }
+
return 0;
}
@@ -83,6 +83,7 @@ struct hantro_h264_dec_reflists {
* @ctrls: V4L2 controls attached to a run
* @dpb_longterm: DPB long-term
* @dpb_valid: DPB valid
+ * @cur_poc: Current picture order count
*/
struct hantro_h264_dec_hw_ctx {
struct hantro_aux_buf priv;
@@ -91,6 +92,7 @@ struct hantro_h264_dec_hw_ctx {
struct hantro_h264_dec_ctrls ctrls;
u32 dpb_longterm;
u32 dpb_valid;
+ s32 cur_poc;
};
/**