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/*
* Copyright (C) 2014 Red Hat
* Copyright (C) 2014 Intel Corp.
*
* 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 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 COPYRIGHT HOLDER(S) OR AUTHOR(S) 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.
*
* Authors:
* Rob Clark <robdclark@gmail.com>
* Daniel Vetter <daniel.vetter@ffwll.ch>
*/
#ifndef DRM_ATOMIC_H_
#define DRM_ATOMIC_H_
#include <drm/drm_crtc.h>
#include <drm/drm_util.h>
/**
* struct drm_crtc_commit - track modeset commits on a CRTC
*
* This structure is used to track pending modeset changes and atomic commit on
* a per-CRTC basis. Since updating the list should never block this structure
* is reference counted to allow waiters to safely wait on an event to complete,
* without holding any locks.
*
* It has 3 different events in total to allow a fine-grained synchronization
* between outstanding updates::
*
* atomic commit thread hardware
*
* write new state into hardware ----> ...
* signal hw_done
* switch to new state on next
* ... v/hblank
*
* wait for buffers to show up ...
*
* ... send completion irq
* irq handler signals flip_done
* cleanup old buffers
*
* signal cleanup_done
*
* wait for flip_done <----
* clean up atomic state
*
* The important bit to know is that cleanup_done is the terminal event, but the
* ordering between flip_done and hw_done is entirely up to the specific driver
* and modeset state change.
*
* For an implementation of how to use this look at
* drm_atomic_helper_setup_commit() from the atomic helper library.
*/
struct drm_crtc_commit {
/**
* @crtc:
*
* DRM CRTC for this commit.
*/
struct drm_crtc *crtc;
/**
* @ref:
*
* Reference count for this structure. Needed to allow blocking on
* completions without the risk of the completion disappearing
* meanwhile.
*/
struct kref ref;
/**
* @flip_done:
*
* Will be signaled when the hardware has flipped to the new set of
* buffers. Signals at the same time as when the drm event for this
* commit is sent to userspace, or when an out-fence is singalled. Note
* that for most hardware, in most cases this happens after @hw_done is
* signalled.
*/
struct completion flip_done;
/**
* @hw_done:
*
* Will be signalled when all hw register changes for this commit have
* been written out. Especially when disabling a pipe this can be much
* later than than @flip_done, since that can signal already when the
* screen goes black, whereas to fully shut down a pipe more register
* I/O is required.
*
* Note that this does not need to include separately reference-counted
* resources like backing storage buffer pinning, or runtime pm
* management.
*/
struct completion hw_done;
/**
* @cleanup_done:
*
* Will be signalled after old buffers have been cleaned up by calling
* drm_atomic_helper_cleanup_planes(). Since this can only happen after
* a vblank wait completed it might be a bit later. This completion is
* useful to throttle updates and avoid hardware updates getting ahead
* of the buffer cleanup too much.
*/
struct completion cleanup_done;
/**
* @commit_entry:
*
* Entry on the per-CRTC &drm_crtc.commit_list. Protected by
* $drm_crtc.commit_lock.
*/
struct list_head commit_entry;
/**
* @event:
*
* &drm_pending_vblank_event pointer to clean up private events.
*/
struct drm_pending_vblank_event *event;
/**
* @abort_completion:
*
* A flag that's set after drm_atomic_helper_setup_commit() takes a
* second reference for the completion of $drm_crtc_state.event. It's
* used by the free code to remove the second reference if commit fails.
*/
bool abort_completion;
};
struct __drm_planes_state {
struct drm_plane *ptr;
struct drm_plane_state *state, *old_state, *new_state;
};
struct __drm_crtcs_state {
struct drm_crtc *ptr;
struct drm_crtc_state *state, *old_state, *new_state;
/**
* @commit:
*
* A reference to the CRTC commit object that is kept for use by
* drm_atomic_helper_wait_for_flip_done() after
* drm_atomic_helper_commit_hw_done() is called. This ensures that a
* concurrent commit won't free a commit object that is still in use.
*/
struct drm_crtc_commit *commit;
s32 __user *out_fence_ptr;
u64 last_vblank_count;
};
struct __drm_connnectors_state {
struct drm_connector *ptr;
struct drm_connector_state *state, *old_state, *new_state;
/**
* @out_fence_ptr:
*
* User-provided pointer which the kernel uses to return a sync_file
* file descriptor. Used by writeback connectors to signal completion of
* the writeback.
*/
s32 __user *out_fence_ptr;
};
struct drm_private_obj;
struct drm_private_state;
/**
* struct drm_private_state_funcs - atomic state functions for private objects
*
* These hooks are used by atomic helpers to create, swap and destroy states of
* private objects. The structure itself is used as a vtable to identify the
* associated private object type. Each private object type that needs to be
* added to the atomic states is expected to have an implementation of these
* hooks and pass a pointer to its drm_private_state_funcs struct to
* drm_atomic_get_private_obj_state().
*/
struct drm_private_state_funcs {
/**
* @atomic_duplicate_state:
*
* Duplicate the current state of the private object and return it. It
* is an error to call this before obj->state has been initialized.
*
* RETURNS:
*
* Duplicated atomic state or NULL when obj->state is not
* initialized or allocation failed.
*/
struct drm_private_state *(*atomic_duplicate_state)(struct drm_private_obj *obj);
/**
* @atomic_destroy_state:
*
* Frees the private object state created with @atomic_duplicate_state.
*/
void (*atomic_destroy_state)(struct drm_private_obj *obj,
struct drm_private_state *state);
};
/**
* struct drm_private_obj - base struct for driver private atomic object
*
* A driver private object is initialized by calling
* drm_atomic_private_obj_init() and cleaned up by calling
* drm_atomic_private_obj_fini().
*
* Currently only tracks the state update functions and the opaque driver
* private state itself, but in the future might also track which
* &drm_modeset_lock is required to duplicate and update this object's state.
*
* All private objects must be initialized before the DRM device they are
* attached to is registered to the DRM subsystem (call to drm_dev_register())
* and should stay around until this DRM device is unregistered (call to
* drm_dev_unregister()). In other words, private objects lifetime is tied
* to the DRM device lifetime. This implies that:
*
* 1/ all calls to drm_atomic_private_obj_init() must be done before calling
* drm_dev_register()
* 2/ all calls to drm_atomic_private_obj_fini() must be done after calling
* drm_dev_unregister()
*/
struct drm_private_obj {
/**
* @head: List entry used to attach a private object to a &drm_device
* (queued to &drm_mode_config.privobj_list).
*/
struct list_head head;
/**
* @lock: Modeset lock to protect the state object.
*/
struct drm_modeset_lock lock;
/**
* @state: Current atomic state for this driver private object.
*/
struct drm_private_state *state;
/**
* @funcs:
*
* Functions to manipulate the state of this driver private object, see
* &drm_private_state_funcs.
*/
const struct drm_private_state_funcs *funcs;
};
/**
* drm_for_each_privobj() - private object iterator
*
* @privobj: pointer to the current private object. Updated after each
* iteration
* @dev: the DRM device we want get private objects from
*
* Allows one to iterate over all private objects attached to @dev
*/
#define drm_for_each_privobj(privobj, dev) \
list_for_each_entry(privobj, &(dev)->mode_config.privobj_list, head)
/**
* struct drm_private_state - base struct for driver private object state
* @state: backpointer to global drm_atomic_state
*
* Currently only contains a backpointer to the overall atomic update, but in
* the future also might hold synchronization information similar to e.g.
* &drm_crtc.commit.
*/
struct drm_private_state {
struct drm_atomic_state *state;
};
struct __drm_private_objs_state {
struct drm_private_obj *ptr;
struct drm_private_state *state, *old_state, *new_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
* @num_connector: size of the @connectors and @connector_states arrays
* @connectors: pointer to array of structures with per-connector data
* @num_private_objs: size of the @private_objs array
* @private_objs: pointer to array of private object pointers
* @acquire_ctx: acquire context for this atomic modeset state update
*
* States are added to an atomic update by calling drm_atomic_get_crtc_state(),
* drm_atomic_get_plane_state(), drm_atomic_get_connector_state(), or for
* private state structures, drm_atomic_get_private_obj_state().
*/
struct drm_atomic_state {
struct kref ref;
struct drm_device *dev;
/**
* @allow_modeset:
*
* Allow full modeset. This is used by the ATOMIC IOCTL handler to<
|