From 30d4706ead1da137b2bf6e42e78d583e4e468fb3 Mon Sep 17 00:00:00 2001 From: Simon Ser Date: Wed, 12 May 2021 12:08:24 +0200 Subject: [PATCH 1/2] linux-drm-syncobj-v1: new protocol This is a new Linux explicit synchronization protocol based on DRM synchronization objects [1]. [1]: https://dri.freedesktop.org/docs/drm/gpu/drm-mm.html#drm-sync-objects Signed-off-by: Simon Ser --- meson.build | 1 + staging/linux-drm-syncobj/README | 4 + .../linux-drm-syncobj-v1.xml | 228 ++++++++++++++++++ 3 files changed, 233 insertions(+) create mode 100644 staging/linux-drm-syncobj/README create mode 100644 staging/linux-drm-syncobj/linux-drm-syncobj-v1.xml diff --git a/meson.build b/meson.build index a477e098..1a0d05d6 100644 --- a/meson.build +++ b/meson.build @@ -44,6 +44,7 @@ staging_protocols = { 'ext-idle-notify': ['v1'], 'ext-session-lock': ['v1'], 'fractional-scale': ['v1'], + 'linux-drm-syncobj': ['v1'], 'security-context': ['v1'], 'single-pixel-buffer': ['v1'], 'tearing-control': ['v1'], diff --git a/staging/linux-drm-syncobj/README b/staging/linux-drm-syncobj/README new file mode 100644 index 00000000..a380b314 --- /dev/null +++ b/staging/linux-drm-syncobj/README @@ -0,0 +1,4 @@ +Linux DRM syncobj protocol + +Maintainers: +Simon Ser diff --git a/staging/linux-drm-syncobj/linux-drm-syncobj-v1.xml b/staging/linux-drm-syncobj/linux-drm-syncobj-v1.xml new file mode 100644 index 00000000..31112c24 --- /dev/null +++ b/staging/linux-drm-syncobj/linux-drm-syncobj-v1.xml @@ -0,0 +1,228 @@ + + + + Copyright 2016 The Chromium Authors. + Copyright 2017 Intel Corporation + Copyright 2018 Collabora, Ltd + Copyright 2021 Simon Ser + + Permission is hereby granted, free of charge, to any person obtaining a + copy of this software and associated documentation files (the "Software"), + to deal in the Software without restriction, including without limitation + the rights to use, copy, modify, merge, publish, distribute, sublicense, + and/or sell copies of the Software, and to permit persons to whom the + Software is furnished to do so, subject to the following conditions: + + The above copyright notice and this permission notice (including the next + paragraph) shall be included in all copies or substantial portions of the + Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + DEALINGS IN THE SOFTWARE. + + + + This protocol allows clients to request explicit synchronization for + buffers. It is tied to the Linux DRM synchronization object framework. + + Synchronization refers to co-ordination of pipelined operations performed + on buffers. Most GPU clients will schedule an asynchronous operation to + render to the buffer, then immediately send the buffer to the compositor + to be attached to a surface. + + With implicit synchronization, ensuring that the rendering operation is + complete before the compositor displays the buffer is an implementation + detail handled by either the kernel or userspace graphics driver. + + By contrast, with explicit synchronization, DRM synchronization object + timeline points mark when the asynchronous operations are complete. When + submitting a buffer, the client provides a timeline point which will be + waited on before the compositor accesses the buffer. The client can also + provide a timeline point that the compositor will signal when it no longer + needs to access the buffer contents for the purposes of the surface commit. + + Linux DRM synchronization objects are documented at: + https://dri.freedesktop.org/docs/drm/gpu/drm-mm.html#drm-sync-objects + + Warning! The protocol described in this file is currently in the testing + phase. Backward compatible changes may be added together with the + corresponding interface version bump. Backward incompatible changes can + only be done by creating a new major version of the extension. + + + + + This global is a factory interface, allowing clients to request + explicit synchronization for buffers on a per-surface basis. + + See wp_linux_drm_syncobj_surface_v1 for more information. + + + + + Destroy this explicit synchronization factory object. Other objects + shall not be affected by this request. + + + + + + + + + + + Instantiate an interface extension for the given wl_surface to provide + explicit synchronization. + + If the given wl_surface already has an explicit synchronization object + associated, the surface_exists protocol error is raised. + + Graphics APIs, like EGL or Vulkan, that manage the buffer queue and + commits of a wl_surface themselves, are likely to be using this + extension internally. If a client is using such an API for a + wl_surface, it should not directly use this extension on that surface, + to avoid raising a surface_exists protocol error. + + + + + + + + Import a DRM synchronization object timeline. + + If the FD cannot be imported, the invalid_timeline error is raised. + + + + + + + + + This object represents an explicit synchronization object timeline + imported by the client to the compositor. + + + + + Destroy the synchronization object timeline. Other objects are not + affected by this request, in particular timeline points set by + set_acquire_point and set_release_point are not unset. + + + + + + + This object is an add-on interface for wl_surface to enable explicit + synchronization. + + Each surface can be associated with only one object of this interface at + any time. + + Explicit synchronization is guaranteed to be supported for buffers + created with any version of the linux-dmabuf protocol. Compositors are + free to support explicit synchronization for additional buffer types. + + As long as the wp_linux_drm_syncobj_surface_v1 object is alive, the + compositor may ignore implicit synchronization for buffers attached and + committed to the wl_surface. + + + + + Destroy this surface synchronization object. + + Any timeline point set by this object with set_acquire_point or + set_release_point since the last commit will be discarded by the + compositor. Any timeline point set by this object before the last + commit will not be affected. + + + + + + + + + + + + Set the timeline point that must be signalled before the compositor may + sample from the buffer attached with wl_surface.attach. + + The 64-bit unsigned value combined from point_hi and point_lo is the + point value. + + The acquire point is double-buffered state, and will be applied on the + next wl_surface.commit request for the associated surface. Thus, it + applies only to the buffer that is attached to the surface at commit + time. + + If an acquire point has already been attached during the same commit + cycle, the new point replaces the old one. + + If the associated wl_surface was destroyed, a no_surface error is + raised. + + If at surface commit time the attached buffer does not support explicit + synchronization, an unsupported_buffer error is raised. + + If at surface commit time there is no buffer attached, a no_buffer + error is raised. + + + + + + + + + Set the timeline point that must be signalled by the compositor when it + has finished its usage of the buffer attached with wl_surface.attach + for the relevant commit. + + Once the timeline point is signaled, and assuming the associated buffer + is not pending release from other wl_surface.commit requests on other + surfaces, no additional explicit or implicit synchronization is + required to safely re-use the buffer. + + The 64-bit unsigned value combined from point_hi and point_lo is the + point value. + + The release point is double-buffered state, and will be applied on the + next wl_surface.commit request for the associated surface. Thus, it + applies only to the buffer that is attached to the surface at commit + time. + + If a release point has already been attached during the same commit + cycle, the new point replaces the old one. + + If the associated wl_surface was destroyed, a no_surface error is + raised. + + If at surface commit time the attached buffer does not support explicit + synchronization, an unsupported_buffer error is raised. + + If at surface commit time there is no buffer attached, a no_buffer + error is raised. + + + + + + + -- GitLab From c3457d52718738bc9bf5464ba32a77e62fd8ad81 Mon Sep 17 00:00:00 2001 From: Simon Ser Date: Mon, 16 Oct 2023 10:47:28 +0200 Subject: [PATCH 2/2] linux-explicit-synchronization-v1: add linux-drm-syncobj note The new protocol supersedes this one. Signed-off-by: Simon Ser --- .../linux-explicit-synchronization-unstable-v1.xml | 2 ++ 1 file changed, 2 insertions(+) diff --git a/unstable/linux-explicit-synchronization/linux-explicit-synchronization-unstable-v1.xml b/unstable/linux-explicit-synchronization/linux-explicit-synchronization-unstable-v1.xml index ac916418..35a97353 100644 --- a/unstable/linux-explicit-synchronization/linux-explicit-synchronization-unstable-v1.xml +++ b/unstable/linux-explicit-synchronization/linux-explicit-synchronization-unstable-v1.xml @@ -36,6 +36,8 @@ This interface is derived from Chromium's zcr_linux_explicit_synchronization_v1. + Note: this protocol is superseded by linux-drm-syncobj. + Warning! The protocol described in this file is experimental and backward incompatible changes may be made. Backward compatible changes may be added together with the corresponding interface version bump. -- GitLab