Instead of only allowing the current format, send the default tranches modified
to only contain formats and modifiers suitable for scanout.
In order to not fail when we can't do direct scanout with a given format
(because that may require a modeset, which we don't allow), keep a blacklist
of attempted formats and modifiers for the current client.
This commit makes 10 bits per color channel the default color depth, which
should reduce banding on outputs that support color formats with more than
8 bits per color channel. In order to support this the commit also removes
the dependency of the EglGbmBackend on a specific format and EglConfig and
instead makes those per-Output properties.
Currently, if you move the cursor really fast between two outputs, there
may be stuck cursor on the previous output.
We need to query the old cursor visibility status before updating the
cursor position, otherwise the drm backend may not schedule an update to
move the cursor offscreen.
This commit does away with the special handling of the legacy cursor and
makes it be applied directly in DrmPipeline, using the same state as the
atomic cursor and without dirty flags.
The cursor being set out-of-band with atomic commits creates problems
because it can create false positive for atomic tests, if the cursor
state gets changed in between an atomic test and its matching commit.
This commit also ports the cursor to a swapchain instead of only one
image. This is not strictly required but may prevent artifacts and
will be needed for future optimisations.
If eglSwapBuffers() fails, there won't be a buffer and so we need to
mark the frame as failed. Otherwise, the screen can be frozen.
eglSwapBuffers() can fail if some effect calls makeOpenGLContext()
between RenderBackend::beginFrame() and RenderBackend::endFrame(), which
is the case with the zoom effect. It can set wrong draw surface in
ZoomEffect::recreateTexture()
BUG: 445412
While it could be useful with tiled displays, the isFormatSupported and
supportedModifier functions can be called before prepareModeset, so where
m_formats is still empty. Additionally they're neither in a hot path nor
performance critical.
In case a modeset needs to be performed, the drm backend will test all
pipelines to ensure that new mode won't cause any bandwidth issues on
other outputs, etc.
To do that, it may delay presenting frames. If the new configuration
doesn't work, it needs to notify about failed frames.
However, the relevant code that notifies the RenderLoop about failed
atomic commits doesn't check if there's actually a pending modeset
present.
When switching between VTs, systemd can revoke master permissions from
kwin. To make things even more trickier, kwin can try to present a frame
in that short time span.
The ifdefs for have_gbm obfuscate the code unnecessarily - the drm backend
is not a great experience with qpainter, so in practice noone should ship
it without gbm anyways.
The proprietary NVidia driver now supports gbm, which vastly improves the
user experience. For older devices that will not get gbm support dropping
EglStreams will likely not have a big impact as it has several session breaking
issues anyways.
By removing the backend a lot of logic can be simplified, most notably multi-gpu.
The main motivation behind this change is to move management of drm
blobs out of property wrappers in specialized wrappers to simplify state
management with blobs.
Connector mode blobs are created on demand.
When we switch CRTCs it can happen that a CRTC would stay enabled yet has
no connectors anymore. In this case the kernel may reject our atomic commit,
which would cause the modeset to fail. To counteract that, properly disable
unused drm objects
Currently KWin is combining modesets with presentation, which causes problems
when multiple monitors are used and crtcs need to be switched around, because
taking away a CRTC from another output causes the driver to disable the
other output. In order to avoid such problems, delay presentation until
all pipelines are ready to present and then do a modeset with a single atomic
commit. To process the resulting page flip events properly this commit also
ports KWin to page_flip_handler2 and changes how the pageFlipped and
notifyFrameFailed signals are processed.
Hardware constraints limit the number of crtcs and which connector + crtc
combinations can work together. The current code is searching for working
combinations when a hotplug happens but that's not enough, it also needs
to happen when the user enables or disables outputs and when modesets are
done, and the configuration change needs to be applied with a single atomic
commit.
This commit removes the hard dependency of DrmPipeline on crtcs by moving
the pending state of outputs from the drm objects to DrmPipeline itself,
which ensures that it's independent from the set of drm objects currently
used. It also changes requests from KScreen to be applied truly atomically.
This improves file organization in kwin by putting backends in a single
directory.
It also makes easier to discover kwin's low level components for new
contributors because the plugins directory may come as the last place to
look for. When one hears "plugin", the first thing that comes to mind is
regular plugins, not low level backends.
2021-11-02 09:02:41 +00:00
Renamed from src/plugins/platforms/drm/drm_pipeline.cpp (Browse further)
