xref: /linux/include/drm/drm_atomic.h (revision 50f0033d1a0f3a8e9eed09ab68067fbb57b0669d)
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 
33 /**
34  * struct drm_crtc_commit - track modeset commits on a CRTC
35  *
36  * This structure is used to track pending modeset changes and atomic commit on
37  * a per-CRTC basis. Since updating the list should never block this structure
38  * is reference counted to allow waiters to safely wait on an event to complete,
39  * without holding any locks.
40  *
41  * It has 3 different events in total to allow a fine-grained synchronization
42  * between outstanding updates::
43  *
44  *	atomic commit thread			hardware
45  *
46  * 	write new state into hardware	---->	...
47  * 	signal hw_done
48  * 						switch to new state on next
49  * 	...					v/hblank
50  *
51  *	wait for buffers to show up		...
52  *
53  *	...					send completion irq
54  *						irq handler signals flip_done
55  *	cleanup old buffers
56  *
57  * 	signal cleanup_done
58  *
59  * 	wait for flip_done		<----
60  * 	clean up atomic state
61  *
62  * The important bit to know is that cleanup_done is the terminal event, but the
63  * ordering between flip_done and hw_done is entirely up to the specific driver
64  * and modeset state change.
65  *
66  * For an implementation of how to use this look at
67  * drm_atomic_helper_setup_commit() from the atomic helper library.
68  */
69 struct drm_crtc_commit {
70 	/**
71 	 * @crtc:
72 	 *
73 	 * DRM CRTC for this commit.
74 	 */
75 	struct drm_crtc *crtc;
76 
77 	/**
78 	 * @ref:
79 	 *
80 	 * Reference count for this structure. Needed to allow blocking on
81 	 * completions without the risk of the completion disappearing
82 	 * meanwhile.
83 	 */
84 	struct kref ref;
85 
86 	/**
87 	 * @flip_done:
88 	 *
89 	 * Will be signaled when the hardware has flipped to the new set of
90 	 * buffers. Signals at the same time as when the drm event for this
91 	 * commit is sent to userspace, or when an out-fence is singalled. Note
92 	 * that for most hardware, in most cases this happens after @hw_done is
93 	 * signalled.
94 	 */
95 	struct completion flip_done;
96 
97 	/**
98 	 * @hw_done:
99 	 *
100 	 * Will be signalled when all hw register changes for this commit have
101 	 * been written out. Especially when disabling a pipe this can be much
102 	 * later than than @flip_done, since that can signal already when the
103 	 * screen goes black, whereas to fully shut down a pipe more register
104 	 * I/O is required.
105 	 *
106 	 * Note that this does not need to include separately reference-counted
107 	 * resources like backing storage buffer pinning, or runtime pm
108 	 * management.
109 	 */
110 	struct completion hw_done;
111 
112 	/**
113 	 * @cleanup_done:
114 	 *
115 	 * Will be signalled after old buffers have been cleaned up by calling
116 	 * drm_atomic_helper_cleanup_planes(). Since this can only happen after
117 	 * a vblank wait completed it might be a bit later. This completion is
118 	 * useful to throttle updates and avoid hardware updates getting ahead
119 	 * of the buffer cleanup too much.
120 	 */
121 	struct completion cleanup_done;
122 
123 	/**
124 	 * @commit_entry:
125 	 *
126 	 * Entry on the per-CRTC commit_list. Protected by crtc->commit_lock.
127 	 */
128 	struct list_head commit_entry;
129 
130 	/**
131 	 * @event:
132 	 *
133 	 * &drm_pending_vblank_event pointer to clean up private events.
134 	 */
135 	struct drm_pending_vblank_event *event;
136 };
137 
138 struct __drm_planes_state {
139 	struct drm_plane *ptr;
140 	struct drm_plane_state *state;
141 };
142 
143 struct __drm_crtcs_state {
144 	struct drm_crtc *ptr;
145 	struct drm_crtc_state *state;
146 	struct drm_crtc_commit *commit;
147 	s64 __user *out_fence_ptr;
148 	unsigned last_vblank_count;
149 };
150 
151 struct __drm_connnectors_state {
152 	struct drm_connector *ptr;
153 	struct drm_connector_state *state;
154 };
155 
156 /**
157  * struct drm_atomic_state - the global state object for atomic updates
158  * @ref: count of all references to this state (will not be freed until zero)
159  * @dev: parent DRM device
160  * @allow_modeset: allow full modeset
161  * @legacy_cursor_update: hint to enforce legacy cursor IOCTL semantics
162  * @legacy_set_config: Disable conflicting encoders instead of failing with -EINVAL.
163  * @planes: pointer to array of structures with per-plane data
164  * @crtcs: pointer to array of CRTC pointers
165  * @num_connector: size of the @connectors and @connector_states arrays
166  * @connectors: pointer to array of structures with per-connector data
167  * @acquire_ctx: acquire context for this atomic modeset state update
168  */
169 struct drm_atomic_state {
170 	struct kref ref;
171 
172 	struct drm_device *dev;
173 	bool allow_modeset : 1;
174 	bool legacy_cursor_update : 1;
175 	bool legacy_set_config : 1;
176 	struct __drm_planes_state *planes;
177 	struct __drm_crtcs_state *crtcs;
178 	int num_connector;
179 	struct __drm_connnectors_state *connectors;
180 
181 	struct drm_modeset_acquire_ctx *acquire_ctx;
182 
183 	/**
184 	 * @commit_work:
185 	 *
186 	 * Work item which can be used by the driver or helpers to execute the
187 	 * commit without blocking.
188 	 */
189 	struct work_struct commit_work;
190 };
191 
192 void drm_crtc_commit_put(struct drm_crtc_commit *commit);
193 static inline void drm_crtc_commit_get(struct drm_crtc_commit *commit)
194 {
195 	kref_get(&commit->ref);
196 }
197 
198 struct drm_atomic_state * __must_check
199 drm_atomic_state_alloc(struct drm_device *dev);
200 void drm_atomic_state_clear(struct drm_atomic_state *state);
201 
202 /**
203  * drm_atomic_state_get - acquire a reference to the atomic state
204  * @state: The atomic state
205  *
206  * Returns a new reference to the @state
207  */
208 static inline struct drm_atomic_state *
209 drm_atomic_state_get(struct drm_atomic_state *state)
210 {
211 	kref_get(&state->ref);
212 	return state;
213 }
214 
215 void __drm_atomic_state_free(struct kref *ref);
216 
217 /**
218  * drm_atomic_state_put - release a reference to the atomic state
219  * @state: The atomic state
220  *
221  * This releases a reference to @state which is freed after removing the
222  * final reference. No locking required and callable from any context.
223  */
224 static inline void drm_atomic_state_put(struct drm_atomic_state *state)
225 {
226 	kref_put(&state->ref, __drm_atomic_state_free);
227 }
228 
229 int  __must_check
230 drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state);
231 void drm_atomic_state_default_clear(struct drm_atomic_state *state);
232 void drm_atomic_state_default_release(struct drm_atomic_state *state);
233 
234 struct drm_crtc_state * __must_check
235 drm_atomic_get_crtc_state(struct drm_atomic_state *state,
236 			  struct drm_crtc *crtc);
237 int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
238 		struct drm_crtc_state *state, struct drm_property *property,
239 		uint64_t val);
240 struct drm_plane_state * __must_check
241 drm_atomic_get_plane_state(struct drm_atomic_state *state,
242 			   struct drm_plane *plane);
243 int drm_atomic_plane_set_property(struct drm_plane *plane,
244 		struct drm_plane_state *state, struct drm_property *property,
245 		uint64_t val);
246 struct drm_connector_state * __must_check
247 drm_atomic_get_connector_state(struct drm_atomic_state *state,
248 			       struct drm_connector *connector);
249 int drm_atomic_connector_set_property(struct drm_connector *connector,
250 		struct drm_connector_state *state, struct drm_property *property,
251 		uint64_t val);
252 
253 /**
254  * drm_atomic_get_existing_crtc_state - get crtc state, if it exists
255  * @state: global atomic state object
256  * @crtc: crtc to grab
257  *
258  * This function returns the crtc state for the given crtc, or NULL
259  * if the crtc is not part of the global atomic state.
260  */
261 static inline struct drm_crtc_state *
262 drm_atomic_get_existing_crtc_state(struct drm_atomic_state *state,
263 				   struct drm_crtc *crtc)
264 {
265 	return state->crtcs[drm_crtc_index(crtc)].state;
266 }
267 
268 /**
269  * drm_atomic_get_existing_plane_state - get plane state, if it exists
270  * @state: global atomic state object
271  * @plane: plane to grab
272  *
273  * This function returns the plane state for the given plane, or NULL
274  * if the plane is not part of the global atomic state.
275  */
276 static inline struct drm_plane_state *
277 drm_atomic_get_existing_plane_state(struct drm_atomic_state *state,
278 				    struct drm_plane *plane)
279 {
280 	return state->planes[drm_plane_index(plane)].state;
281 }
282 
283 /**
284  * drm_atomic_get_existing_connector_state - get connector state, if it exists
285  * @state: global atomic state object
286  * @connector: connector to grab
287  *
288  * This function returns the connector state for the given connector,
289  * or NULL if the connector is not part of the global atomic state.
290  */
291 static inline struct drm_connector_state *
292 drm_atomic_get_existing_connector_state(struct drm_atomic_state *state,
293 					struct drm_connector *connector)
294 {
295 	int index = drm_connector_index(connector);
296 
297 	if (index >= state->num_connector)
298 		return NULL;
299 
300 	return state->connectors[index].state;
301 }
302 
303 /**
304  * __drm_atomic_get_current_plane_state - get current plane state
305  * @state: global atomic state object
306  * @plane: plane to grab
307  *
308  * This function returns the plane state for the given plane, either from
309  * @state, or if the plane isn't part of the atomic state update, from @plane.
310  * This is useful in atomic check callbacks, when drivers need to peek at, but
311  * not change, state of other planes, since it avoids threading an error code
312  * back up the call chain.
313  *
314  * WARNING:
315  *
316  * Note that this function is in general unsafe since it doesn't check for the
317  * required locking for access state structures. Drivers must ensure that it is
318  * safe to access the returned state structure through other means. One common
319  * example is when planes are fixed to a single CRTC, and the driver knows that
320  * the CRTC lock is held already. In that case holding the CRTC lock gives a
321  * read-lock on all planes connected to that CRTC. But if planes can be
322  * reassigned things get more tricky. In that case it's better to use
323  * drm_atomic_get_plane_state and wire up full error handling.
324  *
325  * Returns:
326  *
327  * Read-only pointer to the current plane state.
328  */
329 static inline const struct drm_plane_state *
330 __drm_atomic_get_current_plane_state(struct drm_atomic_state *state,
331 				     struct drm_plane *plane)
332 {
333 	if (state->planes[drm_plane_index(plane)].state)
334 		return state->planes[drm_plane_index(plane)].state;
335 
336 	return plane->state;
337 }
338 
339 int __must_check
340 drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
341 			     struct drm_display_mode *mode);
342 int __must_check
343 drm_atomic_set_mode_prop_for_crtc(struct drm_crtc_state *state,
344 				  struct drm_property_blob *blob);
345 int __must_check
346 drm_atomic_set_crtc_for_plane(struct drm_plane_state *plane_state,
347 			      struct drm_crtc *crtc);
348 void drm_atomic_set_fb_for_plane(struct drm_plane_state *plane_state,
349 				 struct drm_framebuffer *fb);
350 void drm_atomic_set_fence_for_plane(struct drm_plane_state *plane_state,
351 				    struct dma_fence *fence);
352 int __must_check
353 drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state,
354 				  struct drm_crtc *crtc);
355 int __must_check
356 drm_atomic_add_affected_connectors(struct drm_atomic_state *state,
357 				   struct drm_crtc *crtc);
358 int __must_check
359 drm_atomic_add_affected_planes(struct drm_atomic_state *state,
360 			       struct drm_crtc *crtc);
361 
362 void drm_atomic_legacy_backoff(struct drm_atomic_state *state);
363 
364 void
365 drm_atomic_clean_old_fb(struct drm_device *dev, unsigned plane_mask, int ret);
366 
367 int __must_check drm_atomic_check_only(struct drm_atomic_state *state);
368 int __must_check drm_atomic_commit(struct drm_atomic_state *state);
369 int __must_check drm_atomic_nonblocking_commit(struct drm_atomic_state *state);
370 
371 void drm_state_dump(struct drm_device *dev, struct drm_printer *p);
372 
373 #define for_each_connector_in_state(__state, connector, connector_state, __i) \
374 	for ((__i) = 0;							\
375 	     (__i) < (__state)->num_connector &&				\
376 	     ((connector) = (__state)->connectors[__i].ptr,			\
377 	     (connector_state) = (__state)->connectors[__i].state, 1); 	\
378 	     (__i)++)							\
379 		for_each_if (connector)
380 
381 #define for_each_crtc_in_state(__state, crtc, crtc_state, __i)	\
382 	for ((__i) = 0;						\
383 	     (__i) < (__state)->dev->mode_config.num_crtc &&	\
384 	     ((crtc) = (__state)->crtcs[__i].ptr,			\
385 	     (crtc_state) = (__state)->crtcs[__i].state, 1);	\
386 	     (__i)++)						\
387 		for_each_if (crtc_state)
388 
389 #define for_each_plane_in_state(__state, plane, plane_state, __i)		\
390 	for ((__i) = 0;							\
391 	     (__i) < (__state)->dev->mode_config.num_total_plane &&	\
392 	     ((plane) = (__state)->planes[__i].ptr,				\
393 	     (plane_state) = (__state)->planes[__i].state, 1);		\
394 	     (__i)++)							\
395 		for_each_if (plane_state)
396 
397 /**
398  * drm_atomic_crtc_needs_modeset - compute combined modeset need
399  * @state: &drm_crtc_state for the CRTC
400  *
401  * To give drivers flexibility struct &drm_crtc_state has 3 booleans to track
402  * whether the state CRTC changed enough to need a full modeset cycle:
403  * connectors_changed, mode_changed and active_changed. This helper simply
404  * combines these three to compute the overall need for a modeset for @state.
405  *
406  * The atomic helper code sets these booleans, but drivers can and should
407  * change them appropriately to accurately represent whether a modeset is
408  * really needed. In general, drivers should avoid full modesets whenever
409  * possible.
410  *
411  * For example if the CRTC mode has changed, and the hardware is able to enact
412  * the requested mode change without going through a full modeset, the driver
413  * should clear mode_changed during its ->atomic_check.
414  */
415 static inline bool
416 drm_atomic_crtc_needs_modeset(const struct drm_crtc_state *state)
417 {
418 	return state->mode_changed || state->active_changed ||
419 	       state->connectors_changed;
420 }
421 
422 #endif /* DRM_ATOMIC_H_ */
423