[PATCH v2 22/23] media: hantro: h264: Make dpb entry management more robust

Nicolas Dufresne
2022-03-31T19:38:12Z

From: Jonas Karlman <jonas@kwiboo.se>

The driver maintains stable slot locations for reference pictures. This
change makes the code more robust by using the reference_ts as key and
by marking all entries invalid right from the start.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
---
drivers/staging/media/hantro/hantro_h264.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/media/hantro/hantro_h264.c b/drivers/staging/media/hantro/hantro_h264.c
index 228629fb3cdf..7377fc26f780 100644
--- a/drivers/staging/media/hantro/hantro_h264.c
+++ b/drivers/staging/media/hantro/hantro_h264.c
@@ -258,8 +258,7 @@ static void prepare_table(struct hantro_ctx *ctx)
static bool dpb_entry_match(const struct v4l2_h264_dpb_entry *a,
const struct v4l2_h264_dpb_entry *b)
{
- return a->top_field_order_cnt == b->top_field_order_cnt &&
- a->bottom_field_order_cnt == b->bottom_field_order_cnt;
+ return a->reference_ts == b->reference_ts;
}

static void update_dpb(struct hantro_ctx *ctx)
@@ -273,13 +272,13 @@ static void update_dpb(struct hantro_ctx *ctx)

/* Disable all entries by default. */
for (i = 0; i < ARRAY_SIZE(ctx->h264_dec.dpb); i++)
- ctx->h264_dec.dpb[i].flags &= ~V4L2_H264_DPB_ENTRY_FLAG_ACTIVE;
+ ctx->h264_dec.dpb[i].flags = 0;

/* Try to match new DPB entries with existing ones by their POCs. */
for (i = 0; i < ARRAY_SIZE(dec_param->dpb); i++) {
const struct v4l2_h264_dpb_entry *ndpb = &dec_param->dpb[i];

- if (!(ndpb->flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE))
+ if (!(ndpb->flags & V4L2_H264_DPB_ENTRY_FLAG_VALID))
continue;

/*
@@ -290,8 +289,7 @@ static void update_dpb(struct hantro_ctx *ctx)
struct v4l2_h264_dpb_entry *cdpb;

cdpb = &ctx->h264_dec.dpb[j];
- if (cdpb->flags & V4L2_H264_DPB_ENTRY_FLAG_ACTIVE ||
- !dpb_entry_match(cdpb, ndpb))
+ if (!dpb_entry_match(cdpb, ndpb))
continue;

*cdpb = *ndpb;
--
2.34.1