Until now, neither drm-intel-fixes nor drm-intel-next branch supports deep color 12bpc.
You have a 12bpc monitor? The patches look like they should be able to utilise such a link, but it will be quite a while before you have a full 64-bpp pipeline to take advantage of undithered 12bpc output.
Maybe we should just track 10 bpc now, and it works.
If we only concerned with 10bpc until we have something to test 12bpc with, we may as well close this report...
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