[PATCH 0/2] media: amphion: copy timestamp from output to capture

Ming Qian ming.qian at nxp.com
Thu Mar 10 23:06:49 PST 2022


There is a timestamp manager in firmware,
so in previous, driver will pass the timestamp to firmware,
and when a frame is decoded or encoded,
firmware will pass the timestamp to driver,
then driver set the timestamp to the capture vb2_buffer.

But there is problem that the timestamp manager will ensure that the
timestamps are monotonically increasing.
So if there are reorder frames, the capture buffer's timestamp is
inconsistent with the timestamp of the corresponding output buffer.

It goes against the description of V4L2_BUF_FLAG_TIMESTAMP_COPY in the
specification

In order to comply with the specification, driver should copy timestamp
from output buffer to capture buffer, and there is an helper function
v4l2_m2m_buf_copy_metadata to handle it.

Ming Qian (2):
  media: amphion: decoder copy timestamp from output to capture
  media: amphion: encoder copy timestamp from output to capture

 drivers/media/platform/amphion/vdec.c     | 89 ++++++++++-------------
 drivers/media/platform/amphion/venc.c     | 47 ++++--------
 drivers/media/platform/amphion/vpu_v4l2.c | 13 ++++
 drivers/media/platform/amphion/vpu_v4l2.h |  1 +
 4 files changed, 70 insertions(+), 80 deletions(-)

-- 
2.33.0




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