The wlr_output API requires compositors to wait for wlr_output.frame
before submitting a new buffer. However, compositors can perform a
commit which doesn't involve a buffer anytime.
If the commit is a modeset, we set DRM_MODE_ATOMIC_ALLOW_MODESET and
block until the commit is done. If it isn't, we currently always
perform a non-blocking commit. This is an issue because a previous
page-flip might still be in flight kernel-side, returning EBUSY.
Fix this by using blocking commits when a buffer isn't submitted by
the compositor.
Closes: https://github.com/swaywm/sway/issues/6962
References: https://gitlab.freedesktop.org/wlroots/wlroots/-/issues/2239
Previously, we were copying wlr_output_state on the stack and
patching it up to be guaranteed to have a proper drmModeModeInfo
stored in it (and not a custom mode). Also, we had a bunch of
helpers deriving DRM-specific information from the generic
wlr_output_state.
Copying the wlr_output_state worked fine so far, but with output
layers we'll be getting a wl_list in there. An empty wl_list stores
two pointers to itself, copying it on the stack blindly results in
infinite loops in wl_list_for_each.
To fix this, rework our DRM backend to stop copying wlr_output_state,
instead add a new struct wlr_drm_connector_state which holds both
the wlr_output_state and additional DRM-specific information.
Using GBM to import DRM dumb buffers tends to not work well. By
using GBM we're calling some driver-specific functions in Mesa.
These functions check whether Mesa can work with the buffer.
Sometimes Mesa has requirements which differ from DRM dumb buffers
and the GBM import will fail (e.g. on amdgpu).
Instead, drop GBM and use drmPrimeFDToHandle directly. But there's
a twist: BO handles are not ref'counted by the kernel and need to
be ref'counted in user-space [1]. libdrm usually performs this
bookkeeping and is used under-the-hood by Mesa.
We can't re-use libdrm for this task without using driver-specific
APIs. So let's just re-implement the ref'counting logic in wlroots.
The wlroots implementation is inspired from amdgpu's in libdrm [2].
Closes: https://github.com/swaywm/wlroots/issues/2916
[1]: https://gitlab.freedesktop.org/mesa/drm/-/merge_requests/110
[2]: 1a4c0ec9ae/amdgpu/handle_table.c
This allows the kernel to access our buffer damage. Some drivers
can take advantage of this, e.g. for PSR2 panels (Panel Self
Refresh) or for transfer over USB.
Closes: https://github.com/swaywm/wlroots/issues/1267
Right now callers of drm_crtc_commit need to check whether the
interface is legacy or atomic before passing the TEST_ONLY flag.
Additionally, the fallbacks for legacy are in-place in the common
code.
Add a test_only arg to the crtc_commit hook. This way, there's no
risk to pass atomic-only flags to the legacy function (add an assert
to ensure this) and all of the legacy-specific logic can be put back
into legacy.c (done in next commit).
Replace it with a new drm_connector_state_is_modeset function that
decides whether a modeset is necessary directly from the
wlr_output_state which is going to be applied.
Stop assuming that the state to be applied is in output->pending in
crtc_commit. This will allow us to remove ephemeral fields in
wlr_drm_crtc, which are used scratch fields to stash temporary
per-commit data.
Stop using wlr_drm_surface.{width,height} to figure out the size of a
gbm_bo. In the future we'll stop using wlr_drm_plane.surf, so these will
be zero. Instead, rely on gbm_bo_get_{width,height}.
The DRM backend is a little special when it comes to wlr_outputs: the
wlr_drm_connectors are long-lived and are created even when no screen is
connected.
A wlr_drm_connector only advertises a wlr_output to the compositor when
a screen is connected. As such, most of wlr_output's state is invalid
when the connector is disconnected.
We want to stop using wlr_output state on disconnected connectors.
Introduce wlr_drm_connector.name which is always valid regardless of the
connector status to avoid reading wlr_output.name when disconnected.
Previously, we only had the pending state (crtc->pending, crtc->mode and
crtc->active). This causes issues when a commit fails: the pending state
is left as-is, and the next commit may read stale data from it.
This will also cause issues when implementing test-only commits: we need
to rollback the pending CRTC state after a test-only commit.
Introduce separate pending and current CRTC states. Properly update the
current state after a commit.
If the atomic commit fails or is test-only, rollback
wlr_drm_crtc.{mode_id,gamma_lut} blob IDs to their previous value. This
prevents the next commits from failing or applying test-only state.
We already have the logic to fallback to the legacy interface above. We
just need to avoid calling atomic_add with a zero prop ID.
Closes: https://github.com/swaywm/wlroots/issues/2187
We don't need a per-CRTC atomic request anymore. Let's make the request
per-commit so that it's easier to debug.
This is also groundwork for supporting wlr_output_test properly.
GAMMA_LUT_SIZE isn't an atomic property. It can be used with the legacy
interface too. So we can unify both codepaths and remove
wlr_drm_interface.crtc_get_gamma_size.
It's no guaranteed to exist though, so we still need to keep the
fallback.
This is a type which manages gbm_surfaces and imported dmabufs in the
same place, and makes the lifetime management between the two shared. It
should lead to easier to understand code, and fewer special cases.
This also contains a fair bit of refactoring to start using this new
type.
Co-authored-by: Simon Ser <contact@emersion.fr>
This requires functions without a prototype definition to be static.
This allows to detect dead code, export less symbols and put shared
functions in headers.
atomic and legacy now both pass the backend as the user data for the
pageflip event. We than retrieve the correct connector by matching on
the crtc_id passed to the page_flip_handler2.
Wlroots also requires the DRM_CRTC_IN_VBLANK_EVENT capability now.
Fixes#1297
We create the EGL config with GBM_FORMAT_ARGB8888, but then initialize GBM BOs
with GBM_FORMAT_XRGB8888. This mismatch confuses Mesa.
Instead, we can always use GBM_FORMAT_ARGB8888, and use DRM_FORMAT_XRGB8888
when calling drmModeAddFB2.
Fixes https://github.com/swaywm/wlroots/issues/1438
This allows the legacy interface to be used instead of atomic if needed. This
is a workaround to make some Intel GPUs work (if this variable is unset) as
well as to make some AMD GPUs work (if this variable is set).
This commit allows outputs that need a CRTC to steal it from
user-disabled outputs. Note that in the case there are enough
CRTCs, disabled outputs don't loose it (so there's no modeset
and plane initialization needed after DPMS). CRTC allocation
still prefers to keep the old configuration, even if that means
allocating an extra CRTC to a disabled output.
CRTC reallocation now happen when enabling/disabling an output as
well as when trying to modeset. When enabling an output without a
CRTC, we realloc to try to steal a CRTC from a disabled output
(that doesn't really need the CRTC). When disabling an output, we
try to give our CRTC to an output that needs one. Modesetting is
similar to enabling.
A new DRM connector field has been added: `desired_enabled`.
Outputs without CRTCs get automatically disabled. This field keeps
track of the state desired by the user, allowing to automatically
re-enable outputs when a CRTC becomes free.
This required some changes to the allocation algorithm. Previously,
the algorithm tried to keep the previous configuration even if a
new configuration with a better score was possible (it only changed
configuration when the old one didn't work anymore). This is now
changed and the old configuration (still preferred) is only
retained without considering new possibilities when it's perfect
(all outputs have CRTCs).
User-disabled outputs now have `possible_crtcs` set to 0, meaning
they can only retain a previous CRTC (not acquire a new one). The
allocation algorithm has been updated to do not bump the score
when assigning a CRTC to a disabled output.
