[PATCH wayland-protocols v5] unstable/drm-lease: DRM lease protocol support
Marius Vlad
marius-cristian.vlad at nxp.com
Tue Sep 4 14:39:02 UTC 2018
Simple protocol extension to manage DRM lease. Based on the work by Keith
Packard in [1], respectively [2].
[1] https://cgit.freedesktop.org/mesa/drm/commit/?id=c4171535389d72e9135c9615cecd07b346fd6d7e
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v4.15-rc9&id=62884cd386b876638720ef88374b31a84ca7ee5f
Changes since v4:
- send also information (gratuitously) about the connector once the client has it
a zwp_kms_lease_connector_v1 object (Philipp Zabel)
- use the destructor of zwp_kms_lease_v1 to revoke the lease,
and remove the zwp_kms_lease_request_v1::revoke request, as this
will no longer be necessary (Philipp Zabel)
- once the client obtains a zwp_kms_lease_v1 object, using the temporary
zwp_kms_lease_request_v1 object is no longer necessary so the client
can freely call its destructor (Philipp Zabel)
- polished the main commentary to reflect these changes and fixed some
minor typos (Philipp Zabel)
- removed 'revoked' event entirely as it adds complexity without adding
too much benefit.
Changes since v3:
- instead of advertising all leasable connectors at once, advertise each
connector for each leasable output. Use an object to represent a
leasable connector and provide a request to add that leasable connector
when creating the lease (Philipp Zabel)
- add two events to handle add_connector request
- add some comments in manager interface to explain how the protocol
is designed to work
Changes since v2:
- advertise connectors when creating a lease request object (Pekka Paalanen)
- when revoking the lease use the lease object instead of lessee id (Pekka Paalanen)
- various grammar/spelling fixes (Pekka Paalanen)
Changes since v1:
- added manager: advertise lease capability and manage the lease (Daniel Stone)
- add request(s) for adding connector/crtc/plane to behave more like dmabuf (Daniel Stone)
Signed-off-by: Marius Vlad <marius-cristian.vlad at nxp.com>
---
An implementation for this version can be found at
https://gitlab.freedesktop.org/marius.vlad0/weston/commits/drm-lease-advertise-each-connnector-object-fixes
Makefile.am | 1 +
unstable/drm-lease/README | 4 +
unstable/drm-lease/drm-lease-unstable-v1.xml | 226 +++++++++++++++++++++++++++
3 files changed, 231 insertions(+)
create mode 100644 unstable/drm-lease/README
create mode 100644 unstable/drm-lease/drm-lease-unstable-v1.xml
diff --git a/Makefile.am b/Makefile.am
index 6394e26..5d13dca 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -4,6 +4,7 @@ unstable_protocols = \
unstable/pointer-gestures/pointer-gestures-unstable-v1.xml \
unstable/fullscreen-shell/fullscreen-shell-unstable-v1.xml \
unstable/linux-dmabuf/linux-dmabuf-unstable-v1.xml \
+ unstable/drm-lease/drm-lease-unstable-v1.xml \
unstable/text-input/text-input-unstable-v1.xml \
unstable/text-input/text-input-unstable-v3.xml \
unstable/input-method/input-method-unstable-v1.xml \
diff --git a/unstable/drm-lease/README b/unstable/drm-lease/README
new file mode 100644
index 0000000..a25600c
--- /dev/null
+++ b/unstable/drm-lease/README
@@ -0,0 +1,4 @@
+Linux DRM lease
+
+Maintainers:
+Marius Vlad <marius-cristian.vlad at nxp.com>
diff --git a/unstable/drm-lease/drm-lease-unstable-v1.xml b/unstable/drm-lease/drm-lease-unstable-v1.xml
new file mode 100644
index 0000000..9fcaea5
--- /dev/null
+++ b/unstable/drm-lease/drm-lease-unstable-v1.xml
@@ -0,0 +1,226 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="drm_lease_unstable_v1">
+
+<copyright>
+ Copyright 2018 NXP
+
+ 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.
+</copyright>
+
+ <interface name="zwp_kms_lease_manager_v1" version="1">
+ <description summary="lease manager">
+ This interface makes use of DRM lease written by Keith Packard.
+
+ A DRM master can create another DRM master and ``lease'' resources it has
+ control over to the new DRM master. Once leased, resources can not be
+ controlled by the owner unless the owner cancels (revokes) the lease, or
+ the new DRM master is closed.
+
+ A lease is a contract between the Lessor (DRM master which has leased out
+ resources to one or more other DRM masters) and a Lessee
+ (DRM master which controls resources leased from another DRM master). This
+ contract specifies which resources may be controlled by the Lessee.
+
+ The Lessee can issue modesetting/page-flipping atomic operations etc.,
+ just like a Lessor using the leased file-descriptor passed by the Lessor.
+
+ Besides the leased file-descriptor, an integer is used to uniquely
+ identify a Lessee within the tree of DRM masters descending from a single
+ Owner. Once the Lessee has finished with the resources it had used, the
+ Lessee ID can be used to revoke that lease.
+
+ Upon connecting to the compositor all leasable connectors will be
+ advertised to the client. These connectors are represented by
+ zwp_kms_lease_connector_v1 interface, and have to be "added" to a lease
+ request object before creating a lease object. This instructs the
+ compositor to use that connector when creating a lease. The client can
+ receive multiple events for multiple leasable connectors and needs a way
+ to discern between various leasable connectors. When receiving this
+ connector object, events will be sent gratuitously so that the
+ client can properly choose which connector wants to use.
+
+ A lease request object is represented by zwp_kms_lease_request_v1
+ interface and is used temporarily as a storage place for objects
+ IDs. Once the client has a lease object it can freely call its
+ destructor, zwp_kms_lease_request_v1::destroy.
+
+ zwp_kms_lease_request_v1::created event will provide a lease object
+ represented by zwp_kms_lease_v1 interface. The client will then use
+ this lease object to retrieve the file-descriptor (leased fd) and
+ use it to perform mode-setting/atomic operations.
+
+ Whilst the operation to revoke a lease requires a lesse id, in our case,
+ calling the destructor for the lease object will cause the lease to be
+ revoked.
+
+ 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.
+ Backward incompatible changes are done by bumping the version number in
+ the protocol and interface names and resetting the interface version.
+ Once the protocol is to be declared stable, the 'z' prefix and the
+ version number in the protocol and interface names are removed and the
+ interface version number is reset.
+ </description>
+
+ <request name="destroy" type="destructor">
+ <description summary="destroys the manager">
+ Destroys the manager object and should be called last.
+ </description>
+ </request>
+
+ <request name="create_lease_req">
+ <description summary="create a temporary object for managing the lease">
+ Create an object for temporarily storing all the KMS resources to be leased.
+ </description>
+ <arg name="params_id" type="new_id" interface="zwp_kms_lease_request_v1"
+ summary="the new temporary"/>
+ </request>
+
+ <event name="connector">
+ <description summary="advertise which connector can be used to request a lease">
+ This event advertises a leasable connector object. When creating a
+ lease pass this object to zwp_kms_lease_request_v1::add_connector. As
+ multiple connectors can be leasable (based on compositor policy),
+ zwp_kms_lease_connector_v1 will send gratuitously events in order
+ to distinguish between different leasable connectors.
+ After the client has added (using
+ zwp_kms_lease_request_v1::add_connector) a leasable
+ connector object, zwp_kms_lease_request_v1::create request should be
+ called for creating a zwp_kms_lease_v1 lease object.
+ </description>
+ <arg name="conn_obj" type="new_id" interface="zwp_kms_lease_connector_v1"
+ summary="the new temporary" />
+ </event>
+
+ </interface>
+
+ <interface name="zwp_kms_lease_v1" version="1">
+ <description summary="the lease object itself">
+ This interface represents the lease object and encapsulates the lease
+ properties. This objected is sent by zwp_kms_lease_request_v1::created
+ event. Use this object to retrieve lease properties.
+ </description>
+
+ <request name="destroy" type="destructor">
+ <description summary="destroys the temporary lease request object">
+ This request ask the compositor to revoke the lease, destroy the lease
+ object and free temporary storage.
+ </description>
+ </request>
+
+ <request name="retrieve_leased_fd">
+ <description summary="request to retrieve info about the lease">
+ Request to retrieve the leased file-descriptor.
+ </description>
+ </request>
+
+ <event name="leased_fd">
+ <description summary="returns information about the lease">
+ This event returns the leased fd which is required for modesetting
+ or querying page flips/atomic modesetting.
+ The client can use the leased fd to find out DRM-related information
+ like connector ID, CRTC ID, and plane ID using drmModeGetLease().
+ Using that information it can derive a suitable mode useful
+ when performing a modeset.
+ </description>
+ <arg name="leased_fd" type="fd" summary="leased fd" />
+ </event>
+
+ </interface>
+
+ <interface name="zwp_kms_lease_connector_v1" version="1">
+ <description summary="zwp_kms_lease_connector_v1">
+ This interface describes a connector object advertised by
+ zwp_kms_lease_manager_v1::connector.
+ </description>
+
+ <event name="name">
+ <description summary="name">
+ Event sent gratuitously to the client representing the connector name.
+ </description>
+ <arg name="conn_name" type="string" summary="connector name" />
+ </event>
+
+ </interface>
+
+ <interface name="zwp_kms_lease_request_v1" version="1">
+ <description summary="lease request object">
+ This interface is used for managing zwp_kms_lease_v1 object. It is used
+ to create a zwp_kms_lease_v1 object (the actual lease object), to revoke
+ it, and to specify from which connector the lease should be created.
+ </description>
+
+ <request name="destroy" type="destructor">
+ <description summary="destroys the lease request object">
+ This destroys the lease request interface, and can be called once
+ the client obtained a zwp_kms_lease_v1 object.
+ </description>
+ </request>
+
+ <request name="add_connector">
+ <description summary="add a leasable connector object">
+ This request is used to create the lease object using the leasable
+ connector object, and must be called before zwp_kms_lease_request_v1::create.
+ </description>
+ <arg name="conn_obj" type="object" interface="zwp_kms_lease_connector_v1"
+ summary="a leasable connector added to the lease"/>
+ </request>
+
+ <request name="create">
+ <description summary="create the lease">
+ This request will create a zwp_kms_lease_v1 object based on
+ zwp_kms_lease_connector_v1 that was added using
+ zwp_kms_lease_request_v1::add_connector.
+ </description>
+ </request>
+
+ <event name="created">
+ <description summary="lease created successfully">
+ This event indicates that the lease has been created. It provides a
+ zwp_kms_lease_v1 object used for retrieving the file-descriptor
+ representing the lease.
+ </description>
+ <arg name="lease_obj" type="new_id" interface="zwp_kms_lease_v1"
+ summary="the lease obj"/>
+ </event>
+
+ <event name="failed">
+ <description summary="lease could not be created">
+ This event indicates that the lease could not be created.
+ </description>
+ </event>
+
+ <event name="connector_add_failed">
+ <description summary="failed to add connector">
+ This event indicates that the leasable connector object specified in
+ zwp_kms_lease_request_v1::add_connector couldn't be added.
+ </description>
+ </event>
+
+ <event name="connector_added">
+ <description summary="connector was added successfully">
+ This event indicates that the leasable connector object specified in
+ zwp_kms_lease_request_v1::add_connector has been added successfully.
+ </description>
+ </event>
+
+ </interface>
+</protocol>
--
2.9.3
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