Also cc Sean, who reviewed the msm patch to double down on the not-so-awesome async solution (I think at least, I'm still not entirely sure what's all going on there):
commit 2d99ced787e3d0f251fa370d2aae83cf2085a8d9 Author: Rob Clark robdclark@chromium.org Date: Thu Aug 29 09:45:16 2019 -0700
drm/msm: async commit support
On Tue, Oct 20, 2020 at 4:39 PM Daniel Vetter daniel.vetter@ffwll.ch wrote:
It's the horror and shouldn't be used. Realized we're not clear on this in a discussion with Rob about what msm is doing to better support async commits.
Cc: Rob Clark robdclark@gmail.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Maxime Ripard mripard@kernel.org Cc: Thomas Zimmermann tzimmermann@suse.de Cc: David Airlie airlied@linux.ie Cc: Daniel Vetter daniel@ffwll.ch
include/drm/drm_atomic.h | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h index d07c851d255b..413fd0ca56a8 100644 --- a/include/drm/drm_atomic.h +++ b/include/drm/drm_atomic.h @@ -308,7 +308,6 @@ struct __drm_private_objs_state {
- struct drm_atomic_state - the global state object for atomic updates
- @ref: count of all references to this state (will not be freed until zero)
- @dev: parent DRM device
- @legacy_cursor_update: hint to enforce legacy cursor IOCTL semantics
- @async_update: hint for asynchronous plane update
- @planes: pointer to array of structures with per-plane data
- @crtcs: pointer to array of CRTC pointers
@@ -336,6 +335,17 @@ struct drm_atomic_state { * drm_atomic_crtc_needs_modeset(). */ bool allow_modeset : 1;
/*** @legacy_cursor_update:** Hint to enforce legacy cursor IOCTL semantics.** WARNING: This is thoroughly broken and pretty much impossible to* implement correctly. Drivers must ignore this and should instead* implement &drm_plane_helper_funcs.atomic_async_check and* &drm_plane_helper_funcs.atomic_async_commit hooks. New users of this* flag are not allowed.*/ bool legacy_cursor_update : 1; bool async_update : 1; /**-- 2.28.0