Empty IN_FORMATS in sun4i-drm

[Jernej Škrabec]

Dne torek, 14. december 2021 ob 13:02:48 CET je Emmanuel Gil Peyrot 
napisal(a):
> Hi,
> 
> After updating Weston from 9f8561e9 to 07326040 (latest master), it
> fails to run on my PinePhone saying “format 0x34325258 not supported by
> output DSI-1” and then exiting.
> 
> This format is XR24, which would be extremely surprising not to be
> present, and drm_info[1] says it is present.  Looking into Weston’s
> code, I found that drm_plane_populate_formats()’s docstring says it uses
> “either the IN_FORMATS blob property (if available), or the plane's
> format list if not.”  Looking back at drm_info, I saw said IN_FORMATS
> blob being empty of formats (while the format list is fully populated):
> "IN_FORMATS" (immutable): blob = 32
> └───DRM_FORMAT_MOD_LINEAR (0x0)

Does this solve your issue? http://ix.io/3Ipo

Best regards,
Jernej

> 
> This makes me think the kernel should populate IN_FORMATS with at least
> the same formats as the format list when supported, or stop advertising
> this property altogether.
> 
> Other compositors (such as phoc) still run file, probably because they
> use the format list exclusively, without consideration for modifiers.
> 
> Besides fixing this driver, would it make sense to also make Weston
> ignore an empty IN_FORMATS and fall back to the format list?
> 
> Thanks,
> 
> [1] https://github.com/ascent12/drm_info
> 
> -- 
> Emmanuel Gil Peyrot
>