Hi, Here is a preliminary version of the H264 decoding support in the cedrus driver. 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: https://github.com/linux-sunxi/libvdpau-sunxi/ This driver is based on the last version of the cedrus driver sent by Paul, based on Request API v13 sent by Hans: https://lkml.org/lkml/2018/5/7/316 This driver has been tested only with baseline profile videos, and is missing a few key features to decode videos with higher profiles. This has been tested using our cedrus-frame-test tool, which should be a quite generic v4l2-to-drm decoder using the request API to demonstrate the video decoding: https://github.com/free-electrons/cedrus-frame-test/, branch h264 However, sending this preliminary version, I'd really like to start a discussion and get some feedback on the user-space API for the H264 controls exposed through the request API. I've been using the controls currently integrated into ChromeOS that have a working version of this particular setup. However, these controls have a number of shortcomings and inconsistencies with other decoding API. I've worked with libva so far, but I've noticed already that: - The kernel UAPI expects to have the nal_ref_idc variable, while libva only exposes whether that frame is a reference frame or not. I've looked at the rockchip driver in the ChromeOS tree, and our own driver, and they both need only the information about whether the frame is a reference one or not, so maybe we should change this? - The H264 bitstream exposes the picture default reference list (for both list 0 and list 1), the slice reference list and an override flag. The libva will only pass the reference list to be used (so either the picture default's or the slice's) depending on the override flag. The kernel UAPI wants the picture default reference list and the slice reference list, but doesn't expose the override flag, which prevents us from configuring properly the hardware. Our video decoding engine needs the three information, but we can easily adapt to having only one. However, having two doesn't really work for us. It's pretty much the only one I've noticed so far, but we should probably fix them already. And there's probably other, feel free to step in. Maxime Ripard (8): media: cedrus: Add wrappers around container_of for our buffers media: cedrus: Add a macro to check for the validity of a control media: cedrus: make engine type more generic media: cedrus: Remove MPEG1 support media: cedrus: Add ops structure media: cedrus: Move IRQ maintainance to cedrus_dec_ops media: cedrus: Add start and stop decoder operations media: cedrus: Add H264 decoding support Pawel Osciak (1): CHROMIUM: v4l: Add H264 low-level decoder API compound controls. drivers/media/platform/sunxi/cedrus/Makefile | 2 +- .../platform/sunxi/cedrus/sunxi_cedrus.c | 23 + .../sunxi/cedrus/sunxi_cedrus_common.h | 81 +++- .../platform/sunxi/cedrus/sunxi_cedrus_dec.c | 38 +- .../platform/sunxi/cedrus/sunxi_cedrus_h264.c | 443 ++++++++++++++++++ .../platform/sunxi/cedrus/sunxi_cedrus_hw.c | 35 +- .../platform/sunxi/cedrus/sunxi_cedrus_hw.h | 6 +- .../sunxi/cedrus/sunxi_cedrus_mpeg2.c | 52 +- .../sunxi/cedrus/sunxi_cedrus_mpeg2.h | 33 -- .../platform/sunxi/cedrus/sunxi_cedrus_regs.h | 22 +- .../sunxi/cedrus/sunxi_cedrus_video.c | 37 +- drivers/media/v4l2-core/v4l2-ctrls.c | 42 ++ include/media/v4l2-ctrls.h | 10 + include/uapi/linux/v4l2-controls.h | 164 +++++++ include/uapi/linux/videodev2.h | 11 + 15 files changed, 912 insertions(+), 87 deletions(-) create mode 100644 drivers/media/platform/sunxi/cedrus/sunxi_cedrus_h264.c delete mode 100644 drivers/media/platform/sunxi/cedrus/sunxi_cedrus_mpeg2.h -- 2.17.0
