Bug 83888 - Use nuclear page flip / atomic mode setting
Summary: Use nuclear page flip / atomic mode setting
Alias: None
Product: Wayland
Classification: Unclassified
Component: weston (show other bugs)
Version: unspecified
Hardware: All Linux (All)
: medium enhancement
Assignee: Wayland bug list
QA Contact:
Depends on:
Reported: 2014-09-15 13:29 UTC by Pekka Paalanen
Modified: 2018-02-07 12:52 UTC (History)
0 users

See Also:
i915 platform:
i915 features:


Description Pekka Paalanen 2014-09-15 13:29:19 UTC
Implement support for universal planes and atomic mode setting / nuclear page flip in Weston's DRM backend. This would finally make hardware overlays work properly, and they could be enabled by default.

There is some work already done:
contains lots of patches from the branching point up to the tip on implementing and fixing the support.

Outdated work is at:

The first thing is to extract all relevant patches from 'next', squash as appropriate, and rebase on Weston master.

Then the usage of the DRM atomic API needs to be rewritten: we need to use the test flag during assign_planes() to check what the kernel driver can handle, so that when the kernel says no, we automatically fall back to GL compositing rather than just fail to display.

Note, that this feature depends on the atomic commit API which is not in any libdrm release yet, and likely not yet in master either. I think we could still upstream this and put it behind a configure switch, so that kernel developers working on atomic/nuclear will have a complex and real test case at hand.
Comment 1 Pekka Paalanen 2015-05-21 08:36:55 UTC
The latest RFC.

git://git.collabora.com/git/user/daniels/weston wip/atomic-modeset

< daniels> pq: oh yeah, if you want to test on a real live system, 
git://git.collabora.com/git/user/daniels/linux.git, branch wip/4.1.x/blob-modes-i915
Comment 2 Pekka Paalanen 2015-06-23 08:51:49 UTC
A new revision of the series from Daniel:
Comment 3 Link Mauve 2018-02-07 12:52:29 UTC
This has been implemented in 598ee9ddf53f, closing as resolved.

Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.