This is Milestone 1 of full support of Atomic Mode Setting (AMS) and
Universal Planes in the KWin DRM backend.
With Milestone 1 we can use the primary plane of a DRM output and do an
AMS commit (this means mode setting aswell as page flipping), if the
driver supports it. Until now the functionality is only tested on Intel
graphics. You need the drm-next kernel for most recent DRM kernel
developments. As boot option set "i915.nuclear_pageflip". Additionally
at the moment AMS is still hidden behind the environment variable
KWIN_DRM_AMS. Set it, if you want to try out AMS.
What needs to be done next: Make it possible to transfer EGL buffers
directly to planes and implement logic for deciding about using a plane
or not for a specific buffer.
You can read more about it on LWN:
https://lwn.net/Articles/653071
And on Martin's blog:
https://blog.martin-graesslin.com/blog/2015/08/layered-compositing/
I used as model previous work by Daniel Stone for Weston:
https://git.collabora.com/cgit/user/daniels/weston.git
Reviewed-by: mgraesslin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D2370
Just like 4e7392b907:
the ownership of the gbm_device must be passed to the Platform as
the ownership of the EGLDisplay is also passed to the Platform and
we may not destroy the gbm_device for an EGLDisplay we are still using.
With this change I could restart the OpenGL compositor successfully
and switch from OpenGL 3.1 to OpenGL 2 without a crash or rendering
issues.
Summary:
KWin needs to support restarting the OpenGL compositor in case of a
graphics reset event.
On Wayland the tricky part is that the applications should not notice
this. Most importantly KWin cannot just destroy the EGLDisplay and create
a new one. But this is how a restart works: the complete compositor gets
torn down and recreated - including the EGLDisplay.
This change moves ownership of the EGLDisplay to the Platform.
The AbstractEglBackend subclasses query the Platform whether there is
already an EGLDisplay. Only if there is no EGLDisplay the EGLDisplay is
created and only if no EGLDisplay is registered with Wayland the bind
is performed.
Another change is regarding the destruction: the AbstractEglDisplay does
no longer unbind the Wayland display and does no longer destroy the
EGLDisplay. The EGLDisplay is destroyed by the Platform - so very late
on application exit. The Wayland display is unbound when the Compositor
terminates.
Test Plan:
Limited testing with the added auto-test. This one needs to
be extended to fully verify that OpenGL applications continue to work.
But this requires build.kde.org to support OpenGL on Wayland.
Reviewers: #kwin, #plasma_on_wayland
Subscribers: plasma-devel, kwin
Tags: #plasma_on_wayland, #kwin
Differential Revision: https://phabricator.kde.org/D2202
Summary:
Source code reorganization:
The base class AbstractBackend got renamed to Platform, thus the
"backends" are "platforms" now. As they are plugins they should go
together with other KWin plugins which are nowadays in the folder
plugins.
So new location is plugins/platforms/
Reviewers: #plasma, sebas
Subscribers: plasma-devel
Projects: #plasma
Differential Revision: https://phabricator.kde.org/D1353
2016-04-12 08:01:27 +02:00
Renamed from backends/drm/egl_gbm_backend.cpp (Browse further)
