[PATCH weston 3/4] simple-dmabuf-drm: use GBM generic calls

[Emilio Pozuelo Monfort]

On 11/07/18 13:55, Daniel Stone wrote:
> Hi Emilio,
> 
> On Wed, 11 Jul 2018 at 12:53, Emilio Pozuelo Monfort <pochu27 at gmail.com> wrote:
>> As for NV12 support: I tried to make gbm support that in
>> backends/dri/gbm_dri.c by adding a mapping to gbm_dri_visuals_table
>> from GBM_FORMAT_NV12 to __DRI_IMAGE_FOURCC_NV12 or DRM_FORMAT_NV12,
>> but that didn't work. I'm not sure what we can do here. Does anybody
>> who know the stack better have any pointers?
> 
> There is no native NV12 support, apart form some special-case handling
> when using them as textures. For NV12, you would want to create two
> separate BOs - one with GBM_FORMAT_R8 (luma/Y), and one with
> GBM_FORMAT_RG88 (chroma/UV), and fill those like you would fill the
> two planes of a native NV12 surface. They can then be combined and
> sent to the compositor as two planes of a single NV12 image.

Aha, thanks! v4 now has working NV12 support.

Emilio