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Subject[PATCH v2 03/10] media: hantro: Fix picture order count table enable
Date
From: Francois Buergisser <fbuergisser@chromium.org>

The picture order count table only makes sense for profiles
higher than Baseline. This is confirmed by the H.264 specification
(See 8.2.1 Decoding process for picture order count), which
clarifies how POC are used for features not present in Baseline.

"""
Picture order counts are used to determine initial picture orderings
for reference pictures in the decoding of B slices, to represent picture
order differences between frames or fields for motion vector derivation
in temporal direct mode, for implicit mode weighted prediction in B slices,
and for decoder conformance checking.
"""

As a side note, this change matches various vendors downstream codebases,
including ChromiumOS and IMX VPU libraries.

Fixes: dea0a82f3d22 ("media: hantro: Add support for H264 decoding on G1")
Signed-off-by: Francois Buergisser <fbuergisser@chromium.org>
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
---
drivers/staging/media/hantro/hantro_g1_h264_dec.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/media/hantro/hantro_g1_h264_dec.c b/drivers/staging/media/hantro/hantro_g1_h264_dec.c
index a1cb18680200..70a6b5b26477 100644
--- a/drivers/staging/media/hantro/hantro_g1_h264_dec.c
+++ b/drivers/staging/media/hantro/hantro_g1_h264_dec.c
@@ -34,9 +34,11 @@ static void set_params(struct hantro_ctx *ctx)
reg = G1_REG_DEC_CTRL0_DEC_AXI_WR_ID(0x0);
if (sps->flags & V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD)
reg |= G1_REG_DEC_CTRL0_SEQ_MBAFF_E;
- reg |= G1_REG_DEC_CTRL0_PICORD_COUNT_E;
- if (sps->profile_idc > 66 && dec_param->nal_ref_idc)
- reg |= G1_REG_DEC_CTRL0_WRITE_MVS_E;
+ if (sps->profile_idc > 66) {
+ reg |= G1_REG_DEC_CTRL0_PICORD_COUNT_E;
+ if (dec_param->nal_ref_idc)
+ reg |= G1_REG_DEC_CTRL0_WRITE_MVS_E;
+ }

if (!(sps->flags & V4L2_H264_SPS_FLAG_FRAME_MBS_ONLY) &&
(sps->flags & V4L2_H264_SPS_FLAG_MB_ADAPTIVE_FRAME_FIELD ||
--
2.17.1
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