When the driver prefered format is not picked by downstream, the
decoders needs to select another format from the list. The selection
was currently unsorted, resulting in 10bit data often being stripped
to 8bit.
To solve this, reorder the formats in an HW preference order. This order
deviates slightly from the preferred order in libgstvideo. This is to
prefer bandwidth saving over better CPU alignment. As an example NV15 is
prefered over P010. We also prefer tiled over linear.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/8522>
V4L2 and DRM choose different, incompatible ways to represent
tiled/compressed etc. formats. While the later uses combinations of
format fourccs and opaque, vendor/hardware specific modifiers, for the
later every such combination is a distinct new format.
Traditionally Gst implemented each of the V4L2 formats if needed.
Given the large number of tiling and compression modes, this is
quite work intensive - and often actually not needed.
In many situations Gst just needs to pass buffers from V4L2 to DRM in
the form of EGL, VK, Wayland or KMS.
Thus implement a direct translation for some V4L2 formats to DRM ones,
limited to the DMA_DRM API, allowing much quicker enablement of formats
while requiring peers to use external implementations (usually Mesa or
KMS) for tiling etc.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/7355>
Copy V4L2_PIX_FMT_P010 define from linux header.
V4L2_PIX_FMT_P010 is the little endian definition of P010 so map
it GST_VIDEO_FORMAT_P010_10LE.
Add it v4l2 default video formats to allows v4l2 decoders to
enumerate and use it.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/2590>
