[PATCH v11 0/4] media: cedrus: Add H264 decoding support

Paul Kocialkowski paul.kocialkowski at bootlin.com
Fri May 24 09:20:27 UTC 2019


Here is a new version of the H264 decoding support in the cedrus

As you might already know, the cedrus driver relies on the Request
API, and is a reverse engineered driver for the video decoding engine
found on the Allwinner SoCs.

This work has been possible thanks to the work done by the people
behind libvdpau-sunxi found here:

I've tested the various ABI using this gdb script:

And this test script:

The application compiled is quite trivial:

The output is:
arm64:  builds/arm64-test-v4l2-h264-structures
        SHA1: 1c48d3868ac9049c6b5efed43a74bf97af710aba
x86:    builds/x86-test-v4l2-h264-structures
        SHA1: 1c48d3868ac9049c6b5efed43a74bf97af710aba
arm:    builds/arm-test-v4l2-h264-structures
        SHA1: 1c48d3868ac9049c6b5efed43a74bf97af710aba
x64:    builds/x64-test-v4l2-h264-structures
        SHA1: 1c48d3868ac9049c6b5efed43a74bf97af710aba

Let me know if there's any flaw using that test setup, or if you have
any comments on the patches.

Maxime and Paul

Changes from v10:
  - Rebased atop the latest next media tree and Jernej's cedrus clock patch.

Changes from v9:
  - Fixed spare warnings about endianness for le32 types in the driver
  - Rebased on next

Changes from v8:
  - Moved the format into a private header and split the controls, format
    and format doc into three commits
  - Changed the name of the variables in v4l2_ctrl_ptr
  - Added a note in the format documentation to mention that the format is
    not stable yet
  - Fixed the label of the format documentation
  - Fixed a reference in the format documentation
  - Added tags
  - Rebase on current next

Changes from v7:
  - Changed the _slice_param and _decode_param to _params

Changes from v6:
  - Rebased on next
  - Renamed the timestamp DPB field to reference_ts
  - Fixed the collision of control type values
  - Removed unused fields
  - Fixed the structure layout that was broken on x86 by reducing the
    num_slices and nal_ref_idc to 16 bits instead of 32

Changes from v5:
  - Made the references to the H264 spec more explicit
  - Added a flag for the IDR pic
  - Fixed typos
  - Rebased on v5.1-rc1

Changes from v4:
  - Changed the luma and chroma weight and offset from s8 to s16
  - Adjusted chroma and luma denominators masks in the driver
  - Casted the luma and chroma offset to prevent an overflow
  - ALways write the interrupt status register
  - Fix a bug in the sram write routine that would write something even if
    the length was 0
  - Make the scaling lists mandatory
  - Made the reference list order explicit in the documentation
  - Made the fact that the slice structure can be an array
  - Renamed the slice format to V4L2_PIX_FMT_H264_SLICE_RAW
  - Rebased on Hans' tag br-v5.1s

Changes from v3:
  - Reintroduced long term reference flag and documented it
  - Reintroduced ref_pic_list_p0/b0/b1 and documented it
  - Documented the DPB flags
  - Treat the scaling matrix as optional in the driver, as documented
  - Free the neighbor buffer
  - Increase the control IDs by a large margin to be safe of collisions
  - Reorder the fields documentation according to the structure layout
  - Change the tag documentation by the timestamp
  - Convert the sram array to size_t
  - Simplify the buffer retrieval from timestamp
  - Rebase

Changes from v2:
  - Simplified _cedrus_write_ref_list as suggested by Jernej
  - Set whether the frame is used as reference using nal_ref_idc
  - Respect chroma_format_idc
  - Fixes for the scaling list and prediction tables
  - Wrote the documentation for the flags
  - Added a bunch of defines to the driver bit fields
  - Reworded the controls and data format descriptions as suggested
    by Hans
  - Reworked the controls' structure field size to avoid padding
  - Removed the long term reference flag
  - Reintroduced the neighbor info buffer
  - Removed the ref_pic_list_p0/b0/b1 arrays that are redundant with the
    one in the DPB
  - used the timestamps instead of tags
  - Rebased on 5.0-rc1

Changes from v1:
  - Rebased on 4.20
  - Did the documentation for the userspace API
  - Used the tags instead of buffer IDs
  - Added a comment to explain why we still needed the swdec trigger
  - Reworked the MV col buffer in order to have one slot per frame
  - Removed the unused neighbor info buffer
  - Made sure to have the same structure offset and alignments across
    32 bits and 64 bits architecture

Maxime Ripard (3):
  media: pixfmt: Add H264 Slice format
  media: pixfmt: Add H264_SLICE_RAW format documentation
  media: cedrus: Add H264 decoding support

Pawel Osciak (1):
  media: uapi: Add H264 low-level decoder API compound controls.

 Documentation/media/uapi/v4l/biblio.rst       |   9 +
 .../media/uapi/v4l/ext-ctrls-codec.rst        | 569 +++++++++++++++++
 .../media/uapi/v4l/pixfmt-compressed.rst      |  25 +
 .../media/uapi/v4l/vidioc-queryctrl.rst       |  30 +
 .../media/videodev2.h.rst.exceptions          |   5 +
 drivers/media/v4l2-core/v4l2-ctrls.c          |  42 ++
 drivers/media/v4l2-core/v4l2-ioctl.c          |   1 +
 drivers/staging/media/sunxi/cedrus/Makefile   |   3 +-
 drivers/staging/media/sunxi/cedrus/cedrus.c   |  31 +
 drivers/staging/media/sunxi/cedrus/cedrus.h   |  38 +-
 .../staging/media/sunxi/cedrus/cedrus_dec.c   |  13 +
 .../staging/media/sunxi/cedrus/cedrus_h264.c  | 576 ++++++++++++++++++
 .../staging/media/sunxi/cedrus/cedrus_hw.c    |   4 +
 .../staging/media/sunxi/cedrus/cedrus_regs.h  |  91 +++
 .../staging/media/sunxi/cedrus/cedrus_video.c |   9 +
 include/media/h264-ctrls.h                    | 197 ++++++
 include/media/v4l2-ctrls.h                    |  13 +-
 17 files changed, 1653 insertions(+), 3 deletions(-)
 create mode 100644 drivers/staging/media/sunxi/cedrus/cedrus_h264.c
 create mode 100644 include/media/h264-ctrls.h


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