[Mesa-dev] 10bit output via KMS

[Emil Velikov]

[dropping dri-devel, adding mesa-dev]

Hi Volker,

Thanks for giving this a stab.

Mesa it has it's own mailing list, take a look at the instruction for
more details [1].

On 24 July 2017 at 13:34, Volker Vogelhuber
<v.vogelhuber at digitalendoscopy.de> wrote:
> I have implemented a display manager application that takes DMB-BUF FDs
> from another process and presents them to a connected output display
> using the KMS infrastructure (drmModeAddFB, etc.). So far this works
> without problems for XRGB8888. Now I wanted to have 10bit color depth
> per channel. I created a FBO with 10bit (by patching the mesa and ex-
> ported it's texture as a file descriptor via eglExportDMABUFImageMESA,
> see attached patch).
> When I try to import that file descriptor via gbm_bo_import it fails
> because in gbm_bo_import, createImageFromFds is called which compares
> the format passed to gbm_bo_import with intel_image_formats. But this
> array does not seem to support 10bit formats. Now I wonder how one
> could output 10bit per color channel to an output connector?
>
>
> ---
>  include/EGL/eglext.h                     |  4 ++++
>  src/egl/drivers/dri2/egl_dri2.c          | 26 +++++++++++++++++++++++++-
>  src/gbm/backends/dri/gbm_dri.c           |  3 +++
>  src/mesa/drivers/dri/i965/intel_screen.c |  2 ++
>  4 files changed, 34 insertions(+), 1 deletion(-)
>
The patch seems to extend(?) existing EGL extension which, I believe,
is not allowed.

It also adds implementations in EGL, GBM and the i965 driver.
Ideally these would be separate patches, or at least the i965 vs rest.

Thanks
Emil

[1] https://www.mesa3d.org/submittingpatches.html