xref: /openbmc/linux/include/drm/drm_atomic.h (revision 9aa2cba7)
1 /*
2  * Copyright (C) 2014 Red Hat
3  * Copyright (C) 2014 Intel Corp.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  *
23  * Authors:
24  * Rob Clark <robdclark@gmail.com>
25  * Daniel Vetter <daniel.vetter@ffwll.ch>
26  */
27 
28 #ifndef DRM_ATOMIC_H_
29 #define DRM_ATOMIC_H_
30 
31 #include <drm/drm_crtc.h>
32 #include <drm/drm_util.h>
33 
34 /**
35  * struct drm_crtc_commit - track modeset commits on a CRTC
36  *
37  * This structure is used to track pending modeset changes and atomic commit on
38  * a per-CRTC basis. Since updating the list should never block, this structure
39  * is reference counted to allow waiters to safely wait on an event to complete,
40  * without holding any locks.
41  *
42  * It has 3 different events in total to allow a fine-grained synchronization
43  * between outstanding updates::
44  *
45  *	atomic commit thread			hardware
46  *
47  * 	write new state into hardware	---->	...
48  * 	signal hw_done
49  * 						switch to new state on next
50  * 	...					v/hblank
51  *
52  *	wait for buffers to show up		...
53  *
54  *	...					send completion irq
55  *						irq handler signals flip_done
56  *	cleanup old buffers
57  *
58  * 	signal cleanup_done
59  *
60  * 	wait for flip_done		<----
61  * 	clean up atomic state
62  *
63  * The important bit to know is that &cleanup_done is the terminal event, but the
64  * ordering between &flip_done and &hw_done is entirely up to the specific driver
65  * and modeset state change.
66  *
67  * For an implementation of how to use this look at
68  * drm_atomic_helper_setup_commit() from the atomic helper library.
69  *
70  * See also drm_crtc_commit_wait().
71  */
72 struct drm_crtc_commit {
73 	/**
74 	 * @crtc:
75 	 *
76 	 * DRM CRTC for this commit.
77 	 */
78 	struct drm_crtc *crtc;
79 
80 	/**
81 	 * @ref:
82 	 *
83 	 * Reference count for this structure. Needed to allow blocking on
84 	 * completions without the risk of the completion disappearing
85 	 * meanwhile.
86 	 */
87 	struct kref ref;
88 
89 	/**
90 	 * @flip_done:
91 	 *
92 	 * Will be signaled when the hardware has flipped to the new set of
93 	 * buffers. Signals at the same time as when the drm event for this
94 	 * commit is sent to userspace, or when an out-fence is singalled. Note
95 	 * that for most hardware, in most cases this happens after @hw_done is
96 	 * signalled.
97 	 *
98 	 * Completion of this stage is signalled implicitly by calling
99 	 * drm_crtc_send_vblank_event() on &drm_crtc_state.event.
100 	 */
101 	struct completion flip_done;
102 
103 	/**
104 	 * @hw_done:
105 	 *
106 	 * Will be signalled when all hw register changes for this commit have
107 	 * been written out. Especially when disabling a pipe this can be much
108 	 * later than @flip_done, since that can signal already when the
109 	 * screen goes black, whereas to fully shut down a pipe more register
110 	 * I/O is required.
111 	 *
112 	 * Note that this does not need to include separately reference-counted
113 	 * resources like backing storage buffer pinning, or runtime pm
114 	 * management.
115 	 *
116 	 * Drivers should call drm_atomic_helper_commit_hw_done() to signal
117 	 * completion of this stage.
118 	 */
119 	struct completion hw_done;
120 
121 	/**
122 	 * @cleanup_done:
123 	 *
124 	 * Will be signalled after old buffers have been cleaned up by calling
125 	 * drm_atomic_helper_cleanup_planes(). Since this can only happen after
126 	 * a vblank wait completed it might be a bit later. This completion is
127 	 * useful to throttle updates and avoid hardware updates getting ahead
128 	 * of the buffer cleanup too much.
129 	 *
130 	 * Drivers should call drm_atomic_helper_commit_cleanup_done() to signal
131 	 * completion of this stage.
132 	 */
133 	struct completion cleanup_done;
134 
135 	/**
136 	 * @commit_entry:
137 	 *
138 	 * Entry on the per-CRTC &drm_crtc.commit_list. Protected by
139 	 * $drm_crtc.commit_lock.
140 	 */
141 	struct list_head commit_entry;
142 
143 	/**
144 	 * @event:
145 	 *
146 	 * &drm_pending_vblank_event pointer to clean up private events.
147 	 */
148 	struct drm_pending_vblank_event *event;
149 
150 	/**
151 	 * @abort_completion:
152 	 *
153 	 * A flag that's set after drm_atomic_helper_setup_commit() takes a
154 	 * second reference for the completion of $drm_crtc_state.event. It's
155 	 * used by the free code to remove the second reference if commit fails.
156 	 */
157 	bool abort_completion;
158 };
159 
160 struct __drm_planes_state {
161 	struct drm_plane *ptr;
162 	struct drm_plane_state *state, *old_state, *new_state;
163 };
164 
165 struct __drm_crtcs_state {
166 	struct drm_crtc *ptr;
167 	struct drm_crtc_state *state, *old_state, *new_state;
168 
169 	/**
170 	 * @commit:
171 	 *
172 	 * A reference to the CRTC commit object that is kept for use by
173 	 * drm_atomic_helper_wait_for_flip_done() after
174 	 * drm_atomic_helper_commit_hw_done() is called. This ensures that a
175 	 * concurrent commit won't free a commit object that is still in use.
176 	 */
177 	struct drm_crtc_commit *commit;
178 
179 	s32 __user *out_fence_ptr;
180 	u64 last_vblank_count;
181 };
182 
183 struct __drm_connnectors_state {
184 	struct drm_connector *ptr;
185 	struct drm_connector_state *state, *old_state, *new_state;
186 	/**
187 	 * @out_fence_ptr:
188 	 *
189 	 * User-provided pointer which the kernel uses to return a sync_file
190 	 * file descriptor. Used by writeback connectors to signal completion of
191 	 * the writeback.
192 	 */
193 	s32 __user *out_fence_ptr;
194 };
195 
196 struct drm_private_obj;
197 struct drm_private_state;
198 
199 /**
200  * struct drm_private_state_funcs - atomic state functions for private objects
201  *
202  * These hooks are used by atomic helpers to create, swap and destroy states of
203  * private objects. The structure itself is used as a vtable to identify the
204  * associated private object type. Each private object type that needs to be
205  * added to the atomic states is expected to have an implementation of these
206  * hooks and pass a pointer to its drm_private_state_funcs struct to
207  * drm_atomic_get_private_obj_state().
208  */
209 struct drm_private_state_funcs {
210 	/**
211 	 * @atomic_duplicate_state:
212 	 *
213 	 * Duplicate the current state of the private object and return it. It
214 	 * is an error to call this before obj->state has been initialized.
215 	 *
216 	 * RETURNS:
217 	 *
218 	 * Duplicated atomic state or NULL when obj->state is not
219 	 * initialized or allocation failed.
220 	 */
221 	struct drm_private_state *(*atomic_duplicate_state)(struct drm_private_obj *obj);
222 
223 	/**
224 	 * @atomic_destroy_state:
225 	 *
226 	 * Frees the private object state created with @atomic_duplicate_state.
227 	 */
228 	void (*atomic_destroy_state)(struct drm_private_obj *obj,
229 				     struct drm_private_state *state);
230 
231 	/**
232 	 * @atomic_print_state:
233 	 *
234 	 * If driver subclasses &struct drm_private_state, it should implement
235 	 * this optional hook for printing additional driver specific state.
236 	 *
237 	 * Do not call this directly, use drm_atomic_private_obj_print_state()
238 	 * instead.
239 	 */
240 	void (*atomic_print_state)(struct drm_printer *p,
241 				   const struct drm_private_state *state);
242 };
243 
244 /**
245  * struct drm_private_obj - base struct for driver private atomic object
246  *
247  * A driver private object is initialized by calling
248  * drm_atomic_private_obj_init() and cleaned up by calling
249  * drm_atomic_private_obj_fini().
250  *
251  * Currently only tracks the state update functions and the opaque driver
252  * private state itself, but in the future might also track which
253  * &drm_modeset_lock is required to duplicate and update this object's state.
254  *
255  * All private objects must be initialized before the DRM device they are
256  * attached to is registered to the DRM subsystem (call to drm_dev_register())
257  * and should stay around until this DRM device is unregistered (call to
258  * drm_dev_unregister()). In other words, private objects lifetime is tied
259  * to the DRM device lifetime. This implies that:
260  *
261  * 1/ all calls to drm_atomic_private_obj_init() must be done before calling
262  *    drm_dev_register()
263  * 2/ all calls to drm_atomic_private_obj_fini() must be done after calling
264  *    drm_dev_unregister()
265  *
266  * If that private object is used to store a state shared by multiple
267  * CRTCs, proper care must be taken to ensure that non-blocking commits are
268  * properly ordered to avoid a use-after-free issue.
269  *
270  * Indeed, assuming a sequence of two non-blocking &drm_atomic_commit on two
271  * different &drm_crtc using different &drm_plane and &drm_connector, so with no
272  * resources shared, there's no guarantee on which commit is going to happen
273  * first. However, the second &drm_atomic_commit will consider the first
274  * &drm_private_obj its old state, and will be in charge of freeing it whenever
275  * the second &drm_atomic_commit is done.
276  *
277  * If the first &drm_atomic_commit happens after it, it will consider its
278  * &drm_private_obj the new state and will be likely to access it, resulting in
279  * an access to a freed memory region. Drivers should store (and get a reference
280  * to) the &drm_crtc_commit structure in our private state in
281  * &drm_mode_config_helper_funcs.atomic_commit_setup, and then wait for that
282  * commit to complete as the first step of
283  * &drm_mode_config_helper_funcs.atomic_commit_tail, similar to
284  * drm_atomic_helper_wait_for_dependencies().
285  */
286 struct drm_private_obj {
287 	/**
288 	 * @head: List entry used to attach a private object to a &drm_device
289 	 * (queued to &drm_mode_config.privobj_list).
290 	 */
291 	struct list_head head;
292 
293 	/**
294 	 * @lock: Modeset lock to protect the state object.
295 	 */
296 	struct drm_modeset_lock lock;
297 
298 	/**
299 	 * @state: Current atomic state for this driver private object.
300 	 */
301 	struct drm_private_state *state;
302 
303 	/**
304 	 * @funcs:
305 	 *
306 	 * Functions to manipulate the state of this driver private object, see
307 	 * &drm_private_state_funcs.
308 	 */
309 	const struct drm_private_state_funcs *funcs;
310 };
311 
312 /**
313  * drm_for_each_privobj() - private object iterator
314  *
315  * @privobj: pointer to the current private object. Updated after each
316  *	     iteration
317  * @dev: the DRM device we want get private objects from
318  *
319  * Allows one to iterate over all private objects attached to @dev
320  */
321 #define drm_for_each_privobj(privobj, dev) \
322 	list_for_each_entry(privobj, &(dev)->mode_config.privobj_list, head)
323 
324 /**
325  * struct drm_private_state - base struct for driver private object state
326  *
327  * Currently only contains a backpointer to the overall atomic update,
328  * and the relevant private object but in the future also might hold
329  * synchronization information similar to e.g. &drm_crtc.commit.
330  */
331 struct drm_private_state {
332 	/**
333 	 * @state: backpointer to global drm_atomic_state
334 	 */
335 	struct drm_atomic_state *state;
336 
337 	/**
338 	 * @obj: backpointer to the private object
339 	 */
340 	struct drm_private_obj *obj;
341 };
342 
343 struct __drm_private_objs_state {
344 	struct drm_private_obj *ptr;
345 	struct drm_private_state *state, *old_state, *new_state;
346 };
347 
348 /**
349  * struct drm_atomic_state - the global state object for atomic updates
350  * @ref: count of all references to this state (will not be freed until zero)
351  * @dev: parent DRM device
352  * @async_update: hint for asynchronous plane update
353  * @planes: pointer to array of structures with per-plane data
354  * @crtcs: pointer to array of CRTC pointers
355  * @num_connector: size of the @connectors and @connector_states arrays
356  * @connectors: pointer to array of structures with per-connector data
357  * @num_private_objs: size of the @private_objs array
358  * @private_objs: pointer to array of private object pointers
359  * @acquire_ctx: acquire context for this atomic modeset state update
360  *
361  * States are added to an atomic update by calling drm_atomic_get_crtc_state(),
362  * drm_atomic_get_plane_state(), drm_atomic_get_connector_state(), or for
363  * private state structures, drm_atomic_get_private_obj_state().
364  */
365 struct drm_atomic_state {
366 	struct kref ref;
367 
368 	struct drm_device *dev;
369 
370 	/**
371 	 * @allow_modeset:
372 	 *
373 	 * Allow full modeset. This is used by the ATOMIC IOCTL handler to
374 	 * implement the DRM_MODE_ATOMIC_ALLOW_MODESET flag. Drivers should
375 	 * never consult this flag, instead looking at the output of
376 	 * drm_atomic_crtc_needs_modeset().
377 	 */
378 	bool allow_modeset : 1;
379 	/**
380 	 * @legacy_cursor_update:
381 	 *
382 	 * Hint to enforce legacy cursor IOCTL semantics.
383 	 *
384 	 * WARNING: This is thoroughly broken and pretty much impossible to
385 	 * implement correctly. Drivers must ignore this and should instead
386 	 * implement &drm_plane_helper_funcs.atomic_async_check and
387 	 * &drm_plane_helper_funcs.atomic_async_commit hooks. New users of this
388 	 * flag are not allowed.
389 	 */
390 	bool legacy_cursor_update : 1;
391 	bool async_update : 1;
392 	/**
393 	 * @duplicated:
394 	 *
395 	 * Indicates whether or not this atomic state was duplicated using
396 	 * drm_atomic_helper_duplicate_state(). Drivers and atomic helpers
397 	 * should use this to fixup normal  inconsistencies in duplicated
398 	 * states.
399 	 */
400 	bool duplicated : 1;
401 	struct __drm_planes_state *planes;
402 	struct __drm_crtcs_state *crtcs;
403 	int num_connector;
404 	struct __drm_connnectors_state *connectors;
405 	int num_private_objs;
406 	struct __drm_private_objs_state *private_objs;
407 
408 	struct drm_modeset_acquire_ctx *acquire_ctx;
409 
410 	/**
411 	 * @fake_commit:
412 	 *
413 	 * Used for signaling unbound planes/connectors.
414 	 * When a connector or plane is not bound to any CRTC, it's still important
415 	 * to preserve linearity to prevent the atomic states from being freed to early.
416 	 *
417 	 * This commit (if set) is not bound to any CRTC, but will be completed when
418 	 * drm_atomic_helper_commit_hw_done() is called.
419 	 */
420 	struct drm_crtc_commit *fake_commit;
421 
422 	/**
423 	 * @commit_work:
424 	 *
425 	 * Work item which can be used by the driver or helpers to execute the
426 	 * commit without blocking.
427 	 */
428 	struct work_struct commit_work;
429 };
430 
431 void __drm_crtc_commit_free(struct kref *kref);
432 
433 /**
434  * drm_crtc_commit_get - acquire a reference to the CRTC commit
435  * @commit: CRTC commit
436  *
437  * Increases the reference of @commit.
438  *
439  * Returns:
440  * The pointer to @commit, with reference increased.
441  */
442 static inline struct drm_crtc_commit *drm_crtc_commit_get(struct drm_crtc_commit *commit)
443 {
444 	kref_get(&commit->ref);
445 	return commit;
446 }
447 
448 /**
449  * drm_crtc_commit_put - release a reference to the CRTC commmit
450  * @commit: CRTC commit
451  *
452  * This releases a reference to @commit which is freed after removing the
453  * final reference. No locking required and callable from any context.
454  */
455 static inline void drm_crtc_commit_put(struct drm_crtc_commit *commit)
456 {
457 	kref_put(&commit->ref, __drm_crtc_commit_free);
458 }
459 
460 int drm_crtc_commit_wait(struct drm_crtc_commit *commit);
461 
462 struct drm_atomic_state * __must_check
463 drm_atomic_state_alloc(struct drm_device *dev);
464 void drm_atomic_state_clear(struct drm_atomic_state *state);
465 
466 /**
467  * drm_atomic_state_get - acquire a reference to the atomic state
468  * @state: The atomic state
469  *
470  * Returns a new reference to the @state
471  */
472 static inline struct drm_atomic_state *
473 drm_atomic_state_get(struct drm_atomic_state *state)
474 {
475 	kref_get(&state->ref);
476 	return state;
477 }
478 
479 void __drm_atomic_state_free(struct kref *ref);
480 
481 /**
482  * drm_atomic_state_put - release a reference to the atomic state
483  * @state: The atomic state
484  *
485  * This releases a reference to @state which is freed after removing the
486  * final reference. No locking required and callable from any context.
487  */
488 static inline void drm_atomic_state_put(struct drm_atomic_state *state)
489 {
490 	kref_put(&state->ref, __drm_atomic_state_free);
491 }
492 
493 int  __must_check
494 drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state);
495 void drm_atomic_state_default_clear(struct drm_atomic_state *state);
496 void drm_atomic_state_default_release(struct drm_atomic_state *state);
497 
498 struct drm_crtc_state * __must_check
499 drm_atomic_get_crtc_state(struct drm_atomic_state *state,
500 			  struct drm_crtc *crtc);
501 struct drm_plane_state * __must_check
502 drm_atomic_get_plane_state(struct drm_atomic_state *state,
503 			   struct drm_plane *plane);
504 struct drm_connector_state * __must_check
505 drm_atomic_get_connector_state(struct drm_atomic_state *state,
506 			       struct drm_connector *connector);
507 
508 void drm_atomic_private_obj_init(struct drm_device *dev,
509 				 struct drm_private_obj *obj,
510 				 struct drm_private_state *state,
511 				 const struct drm_private_state_funcs *funcs);
512 void drm_atomic_private_obj_fini(struct drm_private_obj *obj);
513 
514 struct drm_private_state * __must_check
515 drm_atomic_get_private_obj_state(struct drm_atomic_state *state,
516 				 struct drm_private_obj *obj);
517 struct drm_private_state *
518 drm_atomic_get_old_private_obj_state(const struct drm_atomic_state *state,
519 				     struct drm_private_obj *obj);
520 struct drm_private_state *
521 drm_atomic_get_new_private_obj_state(const struct drm_atomic_state *state,
522 				     struct drm_private_obj *obj);
523 
524 struct drm_connector *
525 drm_atomic_get_old_connector_for_encoder(const struct drm_atomic_state *state,
526 					 struct drm_encoder *encoder);
527 struct drm_connector *
528 drm_atomic_get_new_connector_for_encoder(const struct drm_atomic_state *state,
529 					 struct drm_encoder *encoder);
530 
531 struct drm_crtc *
532 drm_atomic_get_old_crtc_for_encoder(struct drm_atomic_state *state,
533 					 struct drm_encoder *encoder);
534 struct drm_crtc *
535 drm_atomic_get_new_crtc_for_encoder(struct drm_atomic_state *state,
536 					 struct drm_encoder *encoder);
537 
538 /**
539  * drm_atomic_get_existing_crtc_state - get CRTC state, if it exists
540  * @state: global atomic state object
541  * @crtc: CRTC to grab
542  *
543  * This function returns the CRTC state for the given CRTC, or NULL
544  * if the CRTC is not part of the global atomic state.
545  *
546  * This function is deprecated, @drm_atomic_get_old_crtc_state or
547  * @drm_atomic_get_new_crtc_state should be used instead.
548  */
549 static inline struct drm_crtc_state *
550 drm_atomic_get_existing_crtc_state(const struct drm_atomic_state *state,
551 				   struct drm_crtc *crtc)
552 {
553 	return state->crtcs[drm_crtc_index(crtc)].state;
554 }
555 
556 /**
557  * drm_atomic_get_old_crtc_state - get old CRTC state, if it exists
558  * @state: global atomic state object
559  * @crtc: CRTC to grab
560  *
561  * This function returns the old CRTC state for the given CRTC, or
562  * NULL if the CRTC is not part of the global atomic state.
563  */
564 static inline struct drm_crtc_state *
565 drm_atomic_get_old_crtc_state(const struct drm_atomic_state *state,
566 			      struct drm_crtc *crtc)
567 {
568 	return state->crtcs[drm_crtc_index(crtc)].old_state;
569 }
570 /**
571  * drm_atomic_get_new_crtc_state - get new CRTC state, if it exists
572  * @state: global atomic state object
573  * @crtc: CRTC to grab
574  *
575  * This function returns the new CRTC state for the given CRTC, or
576  * NULL if the CRTC is not part of the global atomic state.
577  */
578 static inline struct drm_crtc_state *
579 drm_atomic_get_new_crtc_state(const struct drm_atomic_state *state,
580 			      struct drm_crtc *crtc)
581 {
582 	return state->crtcs[drm_crtc_index(crtc)].new_state;
583 }
584 
585 /**
586  * drm_atomic_get_existing_plane_state - get plane state, if it exists
587  * @state: global atomic state object
588  * @plane: plane to grab
589  *
590  * This function returns the plane state for the given plane, or NULL
591  * if the plane is not part of the global atomic state.
592  *
593  * This function is deprecated, @drm_atomic_get_old_plane_state or
594  * @drm_atomic_get_new_plane_state should be used instead.
595  */
596 static inline struct drm_plane_state *
597 drm_atomic_get_existing_plane_state(const struct drm_atomic_state *state,
598 				    struct drm_plane *plane)
599 {
600 	return state->planes[drm_plane_index(plane)].state;
601 }
602 
603 /**
604  * drm_atomic_get_old_plane_state - get plane state, if it exists
605  * @state: global atomic state object
606  * @plane: plane to grab
607  *
608  * This function returns the old plane state for the given plane, or
609  * NULL if the plane is not part of the global atomic state.
610  */
611 static inline struct drm_plane_state *
612 drm_atomic_get_old_plane_state(const struct drm_atomic_state *state,
613 			       struct drm_plane *plane)
614 {
615 	return state->planes[drm_plane_index(plane)].old_state;
616 }
617 
618 /**
619  * drm_atomic_get_new_plane_state - get plane state, if it exists
620  * @state: global atomic state object
621  * @plane: plane to grab
622  *
623  * This function returns the new plane state for the given plane, or
624  * NULL if the plane is not part of the global atomic state.
625  */
626 static inline struct drm_plane_state *
627 drm_atomic_get_new_plane_state(const struct drm_atomic_state *state,
628 			       struct drm_plane *plane)
629 {
630 	return state->planes[drm_plane_index(plane)].new_state;
631 }
632 
633 /**
634  * drm_atomic_get_existing_connector_state - get connector state, if it exists
635  * @state: global atomic state object
636  * @connector: connector to grab
637  *
638  * This function returns the connector state for the given connector,
639  * or NULL if the connector is not part of the global atomic state.
640  *
641  * This function is deprecated, @drm_atomic_get_old_connector_state or
642  * @drm_atomic_get_new_connector_state should be used instead.
643  */
644 static inline struct drm_connector_state *
645 drm_atomic_get_existing_connector_state(const struct drm_atomic_state *state,
646 					struct drm_connector *connector)
647 {
648 	int index = drm_connector_index(connector);
649 
650 	if (index >= state->num_connector)
651 		return NULL;
652 
653 	return state->connectors[index].state;
654 }
655 
656 /**
657  * drm_atomic_get_old_connector_state - get connector state, if it exists
658  * @state: global atomic state object
659  * @connector: connector to grab
660  *
661  * This function returns the old connector state for the given connector,
662  * or NULL if the connector is not part of the global atomic state.
663  */
664 static inline struct drm_connector_state *
665 drm_atomic_get_old_connector_state(const struct drm_atomic_state *state,
666 				   struct drm_connector *connector)
667 {
668 	int index = drm_connector_index(connector);
669 
670 	if (index >= state->num_connector)
671 		return NULL;
672 
673 	return state->connectors[index].old_state;
674 }
675 
676 /**
677  * drm_atomic_get_new_connector_state - get connector state, if it exists
678  * @state: global atomic state object
679  * @connector: connector to grab
680  *
681  * This function returns the new connector state for the given connector,
682  * or NULL if the connector is not part of the global atomic state.
683  */
684 static inline struct drm_connector_state *
685 drm_atomic_get_new_connector_state(const struct drm_atomic_state *state,
686 				   struct drm_connector *connector)
687 {
688 	int index = drm_connector_index(connector);
689 
690 	if (index >= state->num_connector)
691 		return NULL;
692 
693 	return state->connectors[index].new_state;
694 }
695 
696 /**
697  * __drm_atomic_get_current_plane_state - get current plane state
698  * @state: global atomic state object
699  * @plane: plane to grab
700  *
701  * This function returns the plane state for the given plane, either from
702  * @state, or if the plane isn't part of the atomic state update, from @plane.
703  * This is useful in atomic check callbacks, when drivers need to peek at, but
704  * not change, state of other planes, since it avoids threading an error code
705  * back up the call chain.
706  *
707  * WARNING:
708  *
709  * Note that this function is in general unsafe since it doesn't check for the
710  * required locking for access state structures. Drivers must ensure that it is
711  * safe to access the returned state structure through other means. One common
712  * example is when planes are fixed to a single CRTC, and the driver knows that
713  * the CRTC lock is held already. In that case holding the CRTC lock gives a
714  * read-lock on all planes connected to that CRTC. But if planes can be
715  * reassigned things get more tricky. In that case it's better to use
716  * drm_atomic_get_plane_state and wire up full error handling.
717  *
718  * Returns:
719  *
720  * Read-only pointer to the current plane state.
721  */
722 static inline const struct drm_plane_state *
723 __drm_atomic_get_current_plane_state(const struct drm_atomic_state *state,
724 				     struct drm_plane *plane)
725 {
726 	if (state->planes[drm_plane_index(plane)].state)
727 		return state->planes[drm_plane_index(plane)].state;
728 
729 	return plane->state;
730 }
731 
732 int __must_check
733 drm_atomic_add_encoder_bridges(struct drm_atomic_state *state,
734 			       struct drm_encoder *encoder);
735 int __must_check
736 drm_atomic_add_affected_connectors(struct drm_atomic_state *state,
737 				   struct drm_crtc *crtc);
738 int __must_check
739 drm_atomic_add_affected_planes(struct drm_atomic_state *state,
740 			       struct drm_crtc *crtc);
741 
742 int __must_check drm_atomic_check_only(struct drm_atomic_state *state);
743 int __must_check drm_atomic_commit(struct drm_atomic_state *state);
744 int __must_check drm_atomic_nonblocking_commit(struct drm_atomic_state *state);
745 
746 void drm_state_dump(struct drm_device *dev, struct drm_printer *p);
747 
748 /**
749  * for_each_oldnew_connector_in_state - iterate over all connectors in an atomic update
750  * @__state: &struct drm_atomic_state pointer
751  * @connector: &struct drm_connector iteration cursor
752  * @old_connector_state: &struct drm_connector_state iteration cursor for the
753  * 	old state
754  * @new_connector_state: &struct drm_connector_state iteration cursor for the
755  * 	new state
756  * @__i: int iteration cursor, for macro-internal use
757  *
758  * This iterates over all connectors in an atomic update, tracking both old and
759  * new state. This is useful in places where the state delta needs to be
760  * considered, for example in atomic check functions.
761  */
762 #define for_each_oldnew_connector_in_state(__state, connector, old_connector_state, new_connector_state, __i) \
763 	for ((__i) = 0;								\
764 	     (__i) < (__state)->num_connector;					\
765 	     (__i)++)								\
766 		for_each_if ((__state)->connectors[__i].ptr &&			\
767 			     ((connector) = (__state)->connectors[__i].ptr,	\
768 			     (void)(connector) /* Only to avoid unused-but-set-variable warning */, \
769 			     (old_connector_state) = (__state)->connectors[__i].old_state,	\
770 			     (new_connector_state) = (__state)->connectors[__i].new_state, 1))
771 
772 /**
773  * for_each_old_connector_in_state - iterate over all connectors in an atomic update
774  * @__state: &struct drm_atomic_state pointer
775  * @connector: &struct drm_connector iteration cursor
776  * @old_connector_state: &struct drm_connector_state iteration cursor for the
777  * 	old state
778  * @__i: int iteration cursor, for macro-internal use
779  *
780  * This iterates over all connectors in an atomic update, tracking only the old
781  * state. This is useful in disable functions, where we need the old state the
782  * hardware is still in.
783  */
784 #define for_each_old_connector_in_state(__state, connector, old_connector_state, __i) \
785 	for ((__i) = 0;								\
786 	     (__i) < (__state)->num_connector;					\
787 	     (__i)++)								\
788 		for_each_if ((__state)->connectors[__i].ptr &&			\
789 			     ((connector) = (__state)->connectors[__i].ptr,	\
790 			     (void)(connector) /* Only to avoid unused-but-set-variable warning */, \
791 			     (old_connector_state) = (__state)->connectors[__i].old_state, 1))
792 
793 /**
794  * for_each_new_connector_in_state - iterate over all connectors in an atomic update
795  * @__state: &struct drm_atomic_state pointer
796  * @connector: &struct drm_connector iteration cursor
797  * @new_connector_state: &struct drm_connector_state iteration cursor for the
798  * 	new state
799  * @__i: int iteration cursor, for macro-internal use
800  *
801  * This iterates over all connectors in an atomic update, tracking only the new
802  * state. This is useful in enable functions, where we need the new state the
803  * hardware should be in when the atomic commit operation has completed.
804  */
805 #define for_each_new_connector_in_state(__state, connector, new_connector_state, __i) \
806 	for ((__i) = 0;								\
807 	     (__i) < (__state)->num_connector;					\
808 	     (__i)++)								\
809 		for_each_if ((__state)->connectors[__i].ptr &&			\
810 			     ((connector) = (__state)->connectors[__i].ptr,	\
811 			     (void)(connector) /* Only to avoid unused-but-set-variable warning */, \
812 			     (new_connector_state) = (__state)->connectors[__i].new_state, \
813 			     (void)(new_connector_state) /* Only to avoid unused-but-set-variable warning */, 1))
814 
815 /**
816  * for_each_oldnew_crtc_in_state - iterate over all CRTCs in an atomic update
817  * @__state: &struct drm_atomic_state pointer
818  * @crtc: &struct drm_crtc iteration cursor
819  * @old_crtc_state: &struct drm_crtc_state iteration cursor for the old state
820  * @new_crtc_state: &struct drm_crtc_state iteration cursor for the new state
821  * @__i: int iteration cursor, for macro-internal use
822  *
823  * This iterates over all CRTCs in an atomic update, tracking both old and
824  * new state. This is useful in places where the state delta needs to be
825  * considered, for example in atomic check functions.
826  */
827 #define for_each_oldnew_crtc_in_state(__state, crtc, old_crtc_state, new_crtc_state, __i) \
828 	for ((__i) = 0;							\
829 	     (__i) < (__state)->dev->mode_config.num_crtc;		\
830 	     (__i)++)							\
831 		for_each_if ((__state)->crtcs[__i].ptr &&		\
832 			     ((crtc) = (__state)->crtcs[__i].ptr,	\
833 			      (void)(crtc) /* Only to avoid unused-but-set-variable warning */, \
834 			     (old_crtc_state) = (__state)->crtcs[__i].old_state, \
835 			     (void)(old_crtc_state) /* Only to avoid unused-but-set-variable warning */, \
836 			     (new_crtc_state) = (__state)->crtcs[__i].new_state, \
837 			     (void)(new_crtc_state) /* Only to avoid unused-but-set-variable warning */, 1))
838 
839 /**
840  * for_each_old_crtc_in_state - iterate over all CRTCs in an atomic update
841  * @__state: &struct drm_atomic_state pointer
842  * @crtc: &struct drm_crtc iteration cursor
843  * @old_crtc_state: &struct drm_crtc_state iteration cursor for the old state
844  * @__i: int iteration cursor, for macro-internal use
845  *
846  * This iterates over all CRTCs in an atomic update, tracking only the old
847  * state. This is useful in disable functions, where we need the old state the
848  * hardware is still in.
849  */
850 #define for_each_old_crtc_in_state(__state, crtc, old_crtc_state, __i)	\
851 	for ((__i) = 0;							\
852 	     (__i) < (__state)->dev->mode_config.num_crtc;		\
853 	     (__i)++)							\
854 		for_each_if ((__state)->crtcs[__i].ptr &&		\
855 			     ((crtc) = (__state)->crtcs[__i].ptr,	\
856 			     (void)(crtc) /* Only to avoid unused-but-set-variable warning */, \
857 			     (old_crtc_state) = (__state)->crtcs[__i].old_state, 1))
858 
859 /**
860  * for_each_new_crtc_in_state - iterate over all CRTCs in an atomic update
861  * @__state: &struct drm_atomic_state pointer
862  * @crtc: &struct drm_crtc iteration cursor
863  * @new_crtc_state: &struct drm_crtc_state iteration cursor for the new state
864  * @__i: int iteration cursor, for macro-internal use
865  *
866  * This iterates over all CRTCs in an atomic update, tracking only the new
867  * state. This is useful in enable functions, where we need the new state the
868  * hardware should be in when the atomic commit operation has completed.
869  */
870 #define for_each_new_crtc_in_state(__state, crtc, new_crtc_state, __i)	\
871 	for ((__i) = 0;							\
872 	     (__i) < (__state)->dev->mode_config.num_crtc;		\
873 	     (__i)++)							\
874 		for_each_if ((__state)->crtcs[__i].ptr &&		\
875 			     ((crtc) = (__state)->crtcs[__i].ptr,	\
876 			     (void)(crtc) /* Only to avoid unused-but-set-variable warning */, \
877 			     (new_crtc_state) = (__state)->crtcs[__i].new_state, \
878 			     (void)(new_crtc_state) /* Only to avoid unused-but-set-variable warning */, 1))
879 
880 /**
881  * for_each_oldnew_plane_in_state - iterate over all planes in an atomic update
882  * @__state: &struct drm_atomic_state pointer
883  * @plane: &struct drm_plane iteration cursor
884  * @old_plane_state: &struct drm_plane_state iteration cursor for the old state
885  * @new_plane_state: &struct drm_plane_state iteration cursor for the new state
886  * @__i: int iteration cursor, for macro-internal use
887  *
888  * This iterates over all planes in an atomic update, tracking both old and
889  * new state. This is useful in places where the state delta needs to be
890  * considered, for example in atomic check functions.
891  */
892 #define for_each_oldnew_plane_in_state(__state, plane, old_plane_state, new_plane_state, __i) \
893 	for ((__i) = 0;							\
894 	     (__i) < (__state)->dev->mode_config.num_total_plane;	\
895 	     (__i)++)							\
896 		for_each_if ((__state)->planes[__i].ptr &&		\
897 			     ((plane) = (__state)->planes[__i].ptr,	\
898 			      (void)(plane) /* Only to avoid unused-but-set-variable warning */, \
899 			      (old_plane_state) = (__state)->planes[__i].old_state,\
900 			      (new_plane_state) = (__state)->planes[__i].new_state, 1))
901 
902 /**
903  * for_each_oldnew_plane_in_state_reverse - iterate over all planes in an atomic
904  * update in reverse order
905  * @__state: &struct drm_atomic_state pointer
906  * @plane: &struct drm_plane iteration cursor
907  * @old_plane_state: &struct drm_plane_state iteration cursor for the old state
908  * @new_plane_state: &struct drm_plane_state iteration cursor for the new state
909  * @__i: int iteration cursor, for macro-internal use
910  *
911  * This iterates over all planes in an atomic update in reverse order,
912  * tracking both old and  new state. This is useful in places where the
913  * state delta needs to be considered, for example in atomic check functions.
914  */
915 #define for_each_oldnew_plane_in_state_reverse(__state, plane, old_plane_state, new_plane_state, __i) \
916 	for ((__i) = ((__state)->dev->mode_config.num_total_plane - 1);	\
917 	     (__i) >= 0;						\
918 	     (__i)--)							\
919 		for_each_if ((__state)->planes[__i].ptr &&		\
920 			     ((plane) = (__state)->planes[__i].ptr,	\
921 			      (old_plane_state) = (__state)->planes[__i].old_state,\
922 			      (new_plane_state) = (__state)->planes[__i].new_state, 1))
923 
924 /**
925  * for_each_new_plane_in_state_reverse - other than only tracking new state,
926  * it's the same as for_each_oldnew_plane_in_state_reverse
927  * @__state: &struct drm_atomic_state pointer
928  * @plane: &struct drm_plane iteration cursor
929  * @new_plane_state: &struct drm_plane_state iteration cursor for the new state
930  * @__i: int iteration cursor, for macro-internal use
931  */
932 #define for_each_new_plane_in_state_reverse(__state, plane, new_plane_state, __i) \
933 	for ((__i) = ((__state)->dev->mode_config.num_total_plane - 1);	\
934 	     (__i) >= 0;						\
935 	     (__i)--)							\
936 		for_each_if ((__state)->planes[__i].ptr &&		\
937 			     ((plane) = (__state)->planes[__i].ptr,	\
938 			      (new_plane_state) = (__state)->planes[__i].new_state, 1))
939 
940 /**
941  * for_each_old_plane_in_state - iterate over all planes in an atomic update
942  * @__state: &struct drm_atomic_state pointer
943  * @plane: &struct drm_plane iteration cursor
944  * @old_plane_state: &struct drm_plane_state iteration cursor for the old state
945  * @__i: int iteration cursor, for macro-internal use
946  *
947  * This iterates over all planes in an atomic update, tracking only the old
948  * state. This is useful in disable functions, where we need the old state the
949  * hardware is still in.
950  */
951 #define for_each_old_plane_in_state(__state, plane, old_plane_state, __i) \
952 	for ((__i) = 0;							\
953 	     (__i) < (__state)->dev->mode_config.num_total_plane;	\
954 	     (__i)++)							\
955 		for_each_if ((__state)->planes[__i].ptr &&		\
956 			     ((plane) = (__state)->planes[__i].ptr,	\
957 			      (old_plane_state) = (__state)->planes[__i].old_state, 1))
958 /**
959  * for_each_new_plane_in_state - iterate over all planes in an atomic update
960  * @__state: &struct drm_atomic_state pointer
961  * @plane: &struct drm_plane iteration cursor
962  * @new_plane_state: &struct drm_plane_state iteration cursor for the new state
963  * @__i: int iteration cursor, for macro-internal use
964  *
965  * This iterates over all planes in an atomic update, tracking only the new
966  * state. This is useful in enable functions, where we need the new state the
967  * hardware should be in when the atomic commit operation has completed.
968  */
969 #define for_each_new_plane_in_state(__state, plane, new_plane_state, __i) \
970 	for ((__i) = 0;							\
971 	     (__i) < (__state)->dev->mode_config.num_total_plane;	\
972 	     (__i)++)							\
973 		for_each_if ((__state)->planes[__i].ptr &&		\
974 			     ((plane) = (__state)->planes[__i].ptr,	\
975 			      (void)(plane) /* Only to avoid unused-but-set-variable warning */, \
976 			      (new_plane_state) = (__state)->planes[__i].new_state, \
977 			      (void)(new_plane_state) /* Only to avoid unused-but-set-variable warning */, 1))
978 
979 /**
980  * for_each_oldnew_private_obj_in_state - iterate over all private objects in an atomic update
981  * @__state: &struct drm_atomic_state pointer
982  * @obj: &struct drm_private_obj iteration cursor
983  * @old_obj_state: &struct drm_private_state iteration cursor for the old state
984  * @new_obj_state: &struct drm_private_state iteration cursor for the new state
985  * @__i: int iteration cursor, for macro-internal use
986  *
987  * This iterates over all private objects in an atomic update, tracking both
988  * old and new state. This is useful in places where the state delta needs
989  * to be considered, for example in atomic check functions.
990  */
991 #define for_each_oldnew_private_obj_in_state(__state, obj, old_obj_state, new_obj_state, __i) \
992 	for ((__i) = 0; \
993 	     (__i) < (__state)->num_private_objs && \
994 		     ((obj) = (__state)->private_objs[__i].ptr, \
995 		      (old_obj_state) = (__state)->private_objs[__i].old_state,	\
996 		      (new_obj_state) = (__state)->private_objs[__i].new_state, 1); \
997 	     (__i)++)
998 
999 /**
1000  * for_each_old_private_obj_in_state - iterate over all private objects in an atomic update
1001  * @__state: &struct drm_atomic_state pointer
1002  * @obj: &struct drm_private_obj iteration cursor
1003  * @old_obj_state: &struct drm_private_state iteration cursor for the old state
1004  * @__i: int iteration cursor, for macro-internal use
1005  *
1006  * This iterates over all private objects in an atomic update, tracking only
1007  * the old state. This is useful in disable functions, where we need the old
1008  * state the hardware is still in.
1009  */
1010 #define for_each_old_private_obj_in_state(__state, obj, old_obj_state, __i) \
1011 	for ((__i) = 0; \
1012 	     (__i) < (__state)->num_private_objs && \
1013 		     ((obj) = (__state)->private_objs[__i].ptr, \
1014 		      (old_obj_state) = (__state)->private_objs[__i].old_state, 1); \
1015 	     (__i)++)
1016 
1017 /**
1018  * for_each_new_private_obj_in_state - iterate over all private objects in an atomic update
1019  * @__state: &struct drm_atomic_state pointer
1020  * @obj: &struct drm_private_obj iteration cursor
1021  * @new_obj_state: &struct drm_private_state iteration cursor for the new state
1022  * @__i: int iteration cursor, for macro-internal use
1023  *
1024  * This iterates over all private objects in an atomic update, tracking only
1025  * the new state. This is useful in enable functions, where we need the new state the
1026  * hardware should be in when the atomic commit operation has completed.
1027  */
1028 #define for_each_new_private_obj_in_state(__state, obj, new_obj_state, __i) \
1029 	for ((__i) = 0; \
1030 	     (__i) < (__state)->num_private_objs && \
1031 		     ((obj) = (__state)->private_objs[__i].ptr, \
1032 		      (void)(obj) /* Only to avoid unused-but-set-variable warning */, \
1033 		      (new_obj_state) = (__state)->private_objs[__i].new_state, 1); \
1034 	     (__i)++)
1035 
1036 /**
1037  * drm_atomic_crtc_needs_modeset - compute combined modeset need
1038  * @state: &drm_crtc_state for the CRTC
1039  *
1040  * To give drivers flexibility &struct drm_crtc_state has 3 booleans to track
1041  * whether the state CRTC changed enough to need a full modeset cycle:
1042  * mode_changed, active_changed and connectors_changed. This helper simply
1043  * combines these three to compute the overall need for a modeset for @state.
1044  *
1045  * The atomic helper code sets these booleans, but drivers can and should
1046  * change them appropriately to accurately represent whether a modeset is
1047  * really needed. In general, drivers should avoid full modesets whenever
1048  * possible.
1049  *
1050  * For example if the CRTC mode has changed, and the hardware is able to enact
1051  * the requested mode change without going through a full modeset, the driver
1052  * should clear mode_changed in its &drm_mode_config_funcs.atomic_check
1053  * implementation.
1054  */
1055 static inline bool
1056 drm_atomic_crtc_needs_modeset(const struct drm_crtc_state *state)
1057 {
1058 	return state->mode_changed || state->active_changed ||
1059 	       state->connectors_changed;
1060 }
1061 
1062 /**
1063  * drm_atomic_crtc_effectively_active - compute whether CRTC is actually active
1064  * @state: &drm_crtc_state for the CRTC
1065  *
1066  * When in self refresh mode, the crtc_state->active value will be false, since
1067  * the CRTC is off. However in some cases we're interested in whether the CRTC
1068  * is active, or effectively active (ie: it's connected to an active display).
1069  * In these cases, use this function instead of just checking active.
1070  */
1071 static inline bool
1072 drm_atomic_crtc_effectively_active(const struct drm_crtc_state *state)
1073 {
1074 	return state->active || state->self_refresh_active;
1075 }
1076 
1077 /**
1078  * struct drm_bus_cfg - bus configuration
1079  *
1080  * This structure stores the configuration of a physical bus between two
1081  * components in an output pipeline, usually between two bridges, an encoder
1082  * and a bridge, or a bridge and a connector.
1083  *
1084  * The bus configuration is stored in &drm_bridge_state separately for the
1085  * input and output buses, as seen from the point of view of each bridge. The
1086  * bus configuration of a bridge output is usually identical to the
1087  * configuration of the next bridge's input, but may differ if the signals are
1088  * modified between the two bridges, for instance by an inverter on the board.
1089  * The input and output configurations of a bridge may differ if the bridge
1090  * modifies the signals internally, for instance by performing format
1091  * conversion, or modifying signals polarities.
1092  */
1093 struct drm_bus_cfg {
1094 	/**
1095 	 * @format: format used on this bus (one of the MEDIA_BUS_FMT_* format)
1096 	 *
1097 	 * This field should not be directly modified by drivers
1098 	 * (drm_atomic_bridge_chain_select_bus_fmts() takes care of the bus
1099 	 * format negotiation).
1100 	 */
1101 	u32 format;
1102 
1103 	/**
1104 	 * @flags: DRM_BUS_* flags used on this bus
1105 	 */
1106 	u32 flags;
1107 };
1108 
1109 /**
1110  * struct drm_bridge_state - Atomic bridge state object
1111  */
1112 struct drm_bridge_state {
1113 	/**
1114 	 * @base: inherit from &drm_private_state
1115 	 */
1116 	struct drm_private_state base;
1117 
1118 	/**
1119 	 * @bridge: the bridge this state refers to
1120 	 */
1121 	struct drm_bridge *bridge;
1122 
1123 	/**
1124 	 * @input_bus_cfg: input bus configuration
1125 	 */
1126 	struct drm_bus_cfg input_bus_cfg;
1127 
1128 	/**
1129 	 * @output_bus_cfg: input bus configuration
1130 	 */
1131 	struct drm_bus_cfg output_bus_cfg;
1132 };
1133 
1134 static inline struct drm_bridge_state *
1135 drm_priv_to_bridge_state(struct drm_private_state *priv)
1136 {
1137 	return container_of(priv, struct drm_bridge_state, base);
1138 }
1139 
1140 struct drm_bridge_state *
1141 drm_atomic_get_bridge_state(struct drm_atomic_state *state,
1142 			    struct drm_bridge *bridge);
1143 struct drm_bridge_state *
1144 drm_atomic_get_old_bridge_state(const struct drm_atomic_state *state,
1145 				struct drm_bridge *bridge);
1146 struct drm_bridge_state *
1147 drm_atomic_get_new_bridge_state(const struct drm_atomic_state *state,
1148 				struct drm_bridge *bridge);
1149 
1150 #endif /* DRM_ATOMIC_H_ */
1151