xref: /linux-6.15/drivers/gpu/drm/drm_atomic.c (revision 78f73bf0)
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 <[email protected]>
25  * Daniel Vetter <[email protected]>
26  */
27 
28 
29 #include <drm/drmP.h>
30 #include <drm/drm_atomic.h>
31 #include <drm/drm_mode.h>
32 #include <drm/drm_plane_helper.h>
33 
34 #include "drm_crtc_internal.h"
35 
36 static void crtc_commit_free(struct kref *kref)
37 {
38 	struct drm_crtc_commit *commit =
39 		container_of(kref, struct drm_crtc_commit, ref);
40 
41 	kfree(commit);
42 }
43 
44 void drm_crtc_commit_put(struct drm_crtc_commit *commit)
45 {
46 	kref_put(&commit->ref, crtc_commit_free);
47 }
48 EXPORT_SYMBOL(drm_crtc_commit_put);
49 
50 /**
51  * drm_atomic_state_default_release -
52  * release memory initialized by drm_atomic_state_init
53  * @state: atomic state
54  *
55  * Free all the memory allocated by drm_atomic_state_init.
56  * This is useful for drivers that subclass the atomic state.
57  */
58 void drm_atomic_state_default_release(struct drm_atomic_state *state)
59 {
60 	kfree(state->connectors);
61 	kfree(state->crtcs);
62 	kfree(state->planes);
63 }
64 EXPORT_SYMBOL(drm_atomic_state_default_release);
65 
66 /**
67  * drm_atomic_state_init - init new atomic state
68  * @dev: DRM device
69  * @state: atomic state
70  *
71  * Default implementation for filling in a new atomic state.
72  * This is useful for drivers that subclass the atomic state.
73  */
74 int
75 drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
76 {
77 	/* TODO legacy paths should maybe do a better job about
78 	 * setting this appropriately?
79 	 */
80 	state->allow_modeset = true;
81 
82 	state->crtcs = kcalloc(dev->mode_config.num_crtc,
83 			       sizeof(*state->crtcs), GFP_KERNEL);
84 	if (!state->crtcs)
85 		goto fail;
86 	state->planes = kcalloc(dev->mode_config.num_total_plane,
87 				sizeof(*state->planes), GFP_KERNEL);
88 	if (!state->planes)
89 		goto fail;
90 
91 	state->dev = dev;
92 
93 	DRM_DEBUG_ATOMIC("Allocated atomic state %p\n", state);
94 
95 	return 0;
96 fail:
97 	drm_atomic_state_default_release(state);
98 	return -ENOMEM;
99 }
100 EXPORT_SYMBOL(drm_atomic_state_init);
101 
102 /**
103  * drm_atomic_state_alloc - allocate atomic state
104  * @dev: DRM device
105  *
106  * This allocates an empty atomic state to track updates.
107  */
108 struct drm_atomic_state *
109 drm_atomic_state_alloc(struct drm_device *dev)
110 {
111 	struct drm_mode_config *config = &dev->mode_config;
112 	struct drm_atomic_state *state;
113 
114 	if (!config->funcs->atomic_state_alloc) {
115 		state = kzalloc(sizeof(*state), GFP_KERNEL);
116 		if (!state)
117 			return NULL;
118 		if (drm_atomic_state_init(dev, state) < 0) {
119 			kfree(state);
120 			return NULL;
121 		}
122 		return state;
123 	}
124 
125 	return config->funcs->atomic_state_alloc(dev);
126 }
127 EXPORT_SYMBOL(drm_atomic_state_alloc);
128 
129 /**
130  * drm_atomic_state_default_clear - clear base atomic state
131  * @state: atomic state
132  *
133  * Default implementation for clearing atomic state.
134  * This is useful for drivers that subclass the atomic state.
135  */
136 void drm_atomic_state_default_clear(struct drm_atomic_state *state)
137 {
138 	struct drm_device *dev = state->dev;
139 	struct drm_mode_config *config = &dev->mode_config;
140 	int i;
141 
142 	DRM_DEBUG_ATOMIC("Clearing atomic state %p\n", state);
143 
144 	for (i = 0; i < state->num_connector; i++) {
145 		struct drm_connector *connector = state->connectors[i].ptr;
146 
147 		if (!connector)
148 			continue;
149 
150 		connector->funcs->atomic_destroy_state(connector,
151 						       state->connectors[i].state);
152 		state->connectors[i].ptr = NULL;
153 		state->connectors[i].state = NULL;
154 		drm_connector_unreference(connector);
155 	}
156 
157 	for (i = 0; i < config->num_crtc; i++) {
158 		struct drm_crtc *crtc = state->crtcs[i].ptr;
159 
160 		if (!crtc)
161 			continue;
162 
163 		crtc->funcs->atomic_destroy_state(crtc,
164 						  state->crtcs[i].state);
165 
166 		if (state->crtcs[i].commit) {
167 			kfree(state->crtcs[i].commit->event);
168 			state->crtcs[i].commit->event = NULL;
169 			drm_crtc_commit_put(state->crtcs[i].commit);
170 		}
171 
172 		state->crtcs[i].commit = NULL;
173 		state->crtcs[i].ptr = NULL;
174 		state->crtcs[i].state = NULL;
175 	}
176 
177 	for (i = 0; i < config->num_total_plane; i++) {
178 		struct drm_plane *plane = state->planes[i].ptr;
179 
180 		if (!plane)
181 			continue;
182 
183 		plane->funcs->atomic_destroy_state(plane,
184 						   state->planes[i].state);
185 		state->planes[i].ptr = NULL;
186 		state->planes[i].state = NULL;
187 	}
188 }
189 EXPORT_SYMBOL(drm_atomic_state_default_clear);
190 
191 /**
192  * drm_atomic_state_clear - clear state object
193  * @state: atomic state
194  *
195  * When the w/w mutex algorithm detects a deadlock we need to back off and drop
196  * all locks. So someone else could sneak in and change the current modeset
197  * configuration. Which means that all the state assembled in @state is no
198  * longer an atomic update to the current state, but to some arbitrary earlier
199  * state. Which could break assumptions the driver's ->atomic_check likely
200  * relies on.
201  *
202  * Hence we must clear all cached state and completely start over, using this
203  * function.
204  */
205 void drm_atomic_state_clear(struct drm_atomic_state *state)
206 {
207 	struct drm_device *dev = state->dev;
208 	struct drm_mode_config *config = &dev->mode_config;
209 
210 	if (config->funcs->atomic_state_clear)
211 		config->funcs->atomic_state_clear(state);
212 	else
213 		drm_atomic_state_default_clear(state);
214 }
215 EXPORT_SYMBOL(drm_atomic_state_clear);
216 
217 /**
218  * drm_atomic_state_free - free all memory for an atomic state
219  * @state: atomic state to deallocate
220  *
221  * This frees all memory associated with an atomic state, including all the
222  * per-object state for planes, crtcs and connectors.
223  */
224 void drm_atomic_state_free(struct drm_atomic_state *state)
225 {
226 	struct drm_device *dev;
227 	struct drm_mode_config *config;
228 
229 	if (!state)
230 		return;
231 
232 	dev = state->dev;
233 	config = &dev->mode_config;
234 
235 	drm_atomic_state_clear(state);
236 
237 	DRM_DEBUG_ATOMIC("Freeing atomic state %p\n", state);
238 
239 	if (config->funcs->atomic_state_free) {
240 		config->funcs->atomic_state_free(state);
241 	} else {
242 		drm_atomic_state_default_release(state);
243 		kfree(state);
244 	}
245 }
246 EXPORT_SYMBOL(drm_atomic_state_free);
247 
248 /**
249  * drm_atomic_get_crtc_state - get crtc state
250  * @state: global atomic state object
251  * @crtc: crtc to get state object for
252  *
253  * This function returns the crtc state for the given crtc, allocating it if
254  * needed. It will also grab the relevant crtc lock to make sure that the state
255  * is consistent.
256  *
257  * Returns:
258  *
259  * Either the allocated state or the error code encoded into the pointer. When
260  * the error is EDEADLK then the w/w mutex code has detected a deadlock and the
261  * entire atomic sequence must be restarted. All other errors are fatal.
262  */
263 struct drm_crtc_state *
264 drm_atomic_get_crtc_state(struct drm_atomic_state *state,
265 			  struct drm_crtc *crtc)
266 {
267 	int ret, index = drm_crtc_index(crtc);
268 	struct drm_crtc_state *crtc_state;
269 
270 	WARN_ON(!state->acquire_ctx);
271 
272 	crtc_state = drm_atomic_get_existing_crtc_state(state, crtc);
273 	if (crtc_state)
274 		return crtc_state;
275 
276 	ret = drm_modeset_lock(&crtc->mutex, state->acquire_ctx);
277 	if (ret)
278 		return ERR_PTR(ret);
279 
280 	crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
281 	if (!crtc_state)
282 		return ERR_PTR(-ENOMEM);
283 
284 	state->crtcs[index].state = crtc_state;
285 	state->crtcs[index].ptr = crtc;
286 	crtc_state->state = state;
287 
288 	DRM_DEBUG_ATOMIC("Added [CRTC:%d:%s] %p state to %p\n",
289 			 crtc->base.id, crtc->name, crtc_state, state);
290 
291 	return crtc_state;
292 }
293 EXPORT_SYMBOL(drm_atomic_get_crtc_state);
294 
295 /**
296  * drm_atomic_set_mode_for_crtc - set mode for CRTC
297  * @state: the CRTC whose incoming state to update
298  * @mode: kernel-internal mode to use for the CRTC, or NULL to disable
299  *
300  * Set a mode (originating from the kernel) on the desired CRTC state. Does
301  * not change any other state properties, including enable, active, or
302  * mode_changed.
303  *
304  * RETURNS:
305  * Zero on success, error code on failure. Cannot return -EDEADLK.
306  */
307 int drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
308 				 struct drm_display_mode *mode)
309 {
310 	struct drm_mode_modeinfo umode;
311 
312 	/* Early return for no change. */
313 	if (mode && memcmp(&state->mode, mode, sizeof(*mode)) == 0)
314 		return 0;
315 
316 	drm_property_unreference_blob(state->mode_blob);
317 	state->mode_blob = NULL;
318 
319 	if (mode) {
320 		drm_mode_convert_to_umode(&umode, mode);
321 		state->mode_blob =
322 			drm_property_create_blob(state->crtc->dev,
323 		                                 sizeof(umode),
324 		                                 &umode);
325 		if (IS_ERR(state->mode_blob))
326 			return PTR_ERR(state->mode_blob);
327 
328 		drm_mode_copy(&state->mode, mode);
329 		state->enable = true;
330 		DRM_DEBUG_ATOMIC("Set [MODE:%s] for CRTC state %p\n",
331 				 mode->name, state);
332 	} else {
333 		memset(&state->mode, 0, sizeof(state->mode));
334 		state->enable = false;
335 		DRM_DEBUG_ATOMIC("Set [NOMODE] for CRTC state %p\n",
336 				 state);
337 	}
338 
339 	return 0;
340 }
341 EXPORT_SYMBOL(drm_atomic_set_mode_for_crtc);
342 
343 /**
344  * drm_atomic_set_mode_prop_for_crtc - set mode for CRTC
345  * @state: the CRTC whose incoming state to update
346  * @blob: pointer to blob property to use for mode
347  *
348  * Set a mode (originating from a blob property) on the desired CRTC state.
349  * This function will take a reference on the blob property for the CRTC state,
350  * and release the reference held on the state's existing mode property, if any
351  * was set.
352  *
353  * RETURNS:
354  * Zero on success, error code on failure. Cannot return -EDEADLK.
355  */
356 int drm_atomic_set_mode_prop_for_crtc(struct drm_crtc_state *state,
357                                       struct drm_property_blob *blob)
358 {
359 	if (blob == state->mode_blob)
360 		return 0;
361 
362 	drm_property_unreference_blob(state->mode_blob);
363 	state->mode_blob = NULL;
364 
365 	memset(&state->mode, 0, sizeof(state->mode));
366 
367 	if (blob) {
368 		if (blob->length != sizeof(struct drm_mode_modeinfo) ||
369 		    drm_mode_convert_umode(&state->mode,
370 		                           (const struct drm_mode_modeinfo *)
371 		                            blob->data))
372 			return -EINVAL;
373 
374 		state->mode_blob = drm_property_reference_blob(blob);
375 		state->enable = true;
376 		DRM_DEBUG_ATOMIC("Set [MODE:%s] for CRTC state %p\n",
377 				 state->mode.name, state);
378 	} else {
379 		state->enable = false;
380 		DRM_DEBUG_ATOMIC("Set [NOMODE] for CRTC state %p\n",
381 				 state);
382 	}
383 
384 	return 0;
385 }
386 EXPORT_SYMBOL(drm_atomic_set_mode_prop_for_crtc);
387 
388 /**
389  * drm_atomic_replace_property_blob - replace a blob property
390  * @blob: a pointer to the member blob to be replaced
391  * @new_blob: the new blob to replace with
392  * @replaced: whether the blob has been replaced
393  *
394  * RETURNS:
395  * Zero on success, error code on failure
396  */
397 static void
398 drm_atomic_replace_property_blob(struct drm_property_blob **blob,
399 				 struct drm_property_blob *new_blob,
400 				 bool *replaced)
401 {
402 	struct drm_property_blob *old_blob = *blob;
403 
404 	if (old_blob == new_blob)
405 		return;
406 
407 	if (old_blob)
408 		drm_property_unreference_blob(old_blob);
409 	if (new_blob)
410 		drm_property_reference_blob(new_blob);
411 	*blob = new_blob;
412 	*replaced = true;
413 
414 	return;
415 }
416 
417 static int
418 drm_atomic_replace_property_blob_from_id(struct drm_crtc *crtc,
419 					 struct drm_property_blob **blob,
420 					 uint64_t blob_id,
421 					 ssize_t expected_size,
422 					 bool *replaced)
423 {
424 	struct drm_device *dev = crtc->dev;
425 	struct drm_property_blob *new_blob = NULL;
426 
427 	if (blob_id != 0) {
428 		new_blob = drm_property_lookup_blob(dev, blob_id);
429 		if (new_blob == NULL)
430 			return -EINVAL;
431 		if (expected_size > 0 && expected_size != new_blob->length)
432 			return -EINVAL;
433 	}
434 
435 	drm_atomic_replace_property_blob(blob, new_blob, replaced);
436 
437 	return 0;
438 }
439 
440 /**
441  * drm_atomic_crtc_set_property - set property on CRTC
442  * @crtc: the drm CRTC to set a property on
443  * @state: the state object to update with the new property value
444  * @property: the property to set
445  * @val: the new property value
446  *
447  * Use this instead of calling crtc->atomic_set_property directly.
448  * This function handles generic/core properties and calls out to
449  * driver's ->atomic_set_property() for driver properties.  To ensure
450  * consistent behavior you must call this function rather than the
451  * driver hook directly.
452  *
453  * RETURNS:
454  * Zero on success, error code on failure
455  */
456 int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
457 		struct drm_crtc_state *state, struct drm_property *property,
458 		uint64_t val)
459 {
460 	struct drm_device *dev = crtc->dev;
461 	struct drm_mode_config *config = &dev->mode_config;
462 	bool replaced = false;
463 	int ret;
464 
465 	if (property == config->prop_active)
466 		state->active = val;
467 	else if (property == config->prop_mode_id) {
468 		struct drm_property_blob *mode =
469 			drm_property_lookup_blob(dev, val);
470 		ret = drm_atomic_set_mode_prop_for_crtc(state, mode);
471 		drm_property_unreference_blob(mode);
472 		return ret;
473 	} else if (property == config->degamma_lut_property) {
474 		ret = drm_atomic_replace_property_blob_from_id(crtc,
475 					&state->degamma_lut,
476 					val,
477 					-1,
478 					&replaced);
479 		state->color_mgmt_changed = replaced;
480 		return ret;
481 	} else if (property == config->ctm_property) {
482 		ret = drm_atomic_replace_property_blob_from_id(crtc,
483 					&state->ctm,
484 					val,
485 					sizeof(struct drm_color_ctm),
486 					&replaced);
487 		state->color_mgmt_changed = replaced;
488 		return ret;
489 	} else if (property == config->gamma_lut_property) {
490 		ret = drm_atomic_replace_property_blob_from_id(crtc,
491 					&state->gamma_lut,
492 					val,
493 					-1,
494 					&replaced);
495 		state->color_mgmt_changed = replaced;
496 		return ret;
497 	} else if (crtc->funcs->atomic_set_property)
498 		return crtc->funcs->atomic_set_property(crtc, state, property, val);
499 	else
500 		return -EINVAL;
501 
502 	return 0;
503 }
504 EXPORT_SYMBOL(drm_atomic_crtc_set_property);
505 
506 /**
507  * drm_atomic_crtc_get_property - get property value from CRTC state
508  * @crtc: the drm CRTC to set a property on
509  * @state: the state object to get the property value from
510  * @property: the property to set
511  * @val: return location for the property value
512  *
513  * This function handles generic/core properties and calls out to
514  * driver's ->atomic_get_property() for driver properties.  To ensure
515  * consistent behavior you must call this function rather than the
516  * driver hook directly.
517  *
518  * RETURNS:
519  * Zero on success, error code on failure
520  */
521 static int
522 drm_atomic_crtc_get_property(struct drm_crtc *crtc,
523 		const struct drm_crtc_state *state,
524 		struct drm_property *property, uint64_t *val)
525 {
526 	struct drm_device *dev = crtc->dev;
527 	struct drm_mode_config *config = &dev->mode_config;
528 
529 	if (property == config->prop_active)
530 		*val = state->active;
531 	else if (property == config->prop_mode_id)
532 		*val = (state->mode_blob) ? state->mode_blob->base.id : 0;
533 	else if (property == config->degamma_lut_property)
534 		*val = (state->degamma_lut) ? state->degamma_lut->base.id : 0;
535 	else if (property == config->ctm_property)
536 		*val = (state->ctm) ? state->ctm->base.id : 0;
537 	else if (property == config->gamma_lut_property)
538 		*val = (state->gamma_lut) ? state->gamma_lut->base.id : 0;
539 	else if (crtc->funcs->atomic_get_property)
540 		return crtc->funcs->atomic_get_property(crtc, state, property, val);
541 	else
542 		return -EINVAL;
543 
544 	return 0;
545 }
546 
547 /**
548  * drm_atomic_crtc_check - check crtc state
549  * @crtc: crtc to check
550  * @state: crtc state to check
551  *
552  * Provides core sanity checks for crtc state.
553  *
554  * RETURNS:
555  * Zero on success, error code on failure
556  */
557 static int drm_atomic_crtc_check(struct drm_crtc *crtc,
558 		struct drm_crtc_state *state)
559 {
560 	/* NOTE: we explicitly don't enforce constraints such as primary
561 	 * layer covering entire screen, since that is something we want
562 	 * to allow (on hw that supports it).  For hw that does not, it
563 	 * should be checked in driver's crtc->atomic_check() vfunc.
564 	 *
565 	 * TODO: Add generic modeset state checks once we support those.
566 	 */
567 
568 	if (state->active && !state->enable) {
569 		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] active without enabled\n",
570 				 crtc->base.id, crtc->name);
571 		return -EINVAL;
572 	}
573 
574 	/* The state->enable vs. state->mode_blob checks can be WARN_ON,
575 	 * as this is a kernel-internal detail that userspace should never
576 	 * be able to trigger. */
577 	if (drm_core_check_feature(crtc->dev, DRIVER_ATOMIC) &&
578 	    WARN_ON(state->enable && !state->mode_blob)) {
579 		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] enabled without mode blob\n",
580 				 crtc->base.id, crtc->name);
581 		return -EINVAL;
582 	}
583 
584 	if (drm_core_check_feature(crtc->dev, DRIVER_ATOMIC) &&
585 	    WARN_ON(!state->enable && state->mode_blob)) {
586 		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] disabled with mode blob\n",
587 				 crtc->base.id, crtc->name);
588 		return -EINVAL;
589 	}
590 
591 	/*
592 	 * Reject event generation for when a CRTC is off and stays off.
593 	 * It wouldn't be hard to implement this, but userspace has a track
594 	 * record of happily burning through 100% cpu (or worse, crash) when the
595 	 * display pipe is suspended. To avoid all that fun just reject updates
596 	 * that ask for events since likely that indicates a bug in the
597 	 * compositor's drawing loop. This is consistent with the vblank IOCTL
598 	 * and legacy page_flip IOCTL which also reject service on a disabled
599 	 * pipe.
600 	 */
601 	if (state->event && !state->active && !crtc->state->active) {
602 		DRM_DEBUG_ATOMIC("[CRTC:%d] requesting event but off\n",
603 				 crtc->base.id);
604 		return -EINVAL;
605 	}
606 
607 	return 0;
608 }
609 
610 /**
611  * drm_atomic_get_plane_state - get plane state
612  * @state: global atomic state object
613  * @plane: plane to get state object for
614  *
615  * This function returns the plane state for the given plane, allocating it if
616  * needed. It will also grab the relevant plane lock to make sure that the state
617  * is consistent.
618  *
619  * Returns:
620  *
621  * Either the allocated state or the error code encoded into the pointer. When
622  * the error is EDEADLK then the w/w mutex code has detected a deadlock and the
623  * entire atomic sequence must be restarted. All other errors are fatal.
624  */
625 struct drm_plane_state *
626 drm_atomic_get_plane_state(struct drm_atomic_state *state,
627 			  struct drm_plane *plane)
628 {
629 	int ret, index = drm_plane_index(plane);
630 	struct drm_plane_state *plane_state;
631 
632 	WARN_ON(!state->acquire_ctx);
633 
634 	plane_state = drm_atomic_get_existing_plane_state(state, plane);
635 	if (plane_state)
636 		return plane_state;
637 
638 	ret = drm_modeset_lock(&plane->mutex, state->acquire_ctx);
639 	if (ret)
640 		return ERR_PTR(ret);
641 
642 	plane_state = plane->funcs->atomic_duplicate_state(plane);
643 	if (!plane_state)
644 		return ERR_PTR(-ENOMEM);
645 
646 	state->planes[index].state = plane_state;
647 	state->planes[index].ptr = plane;
648 	plane_state->state = state;
649 
650 	DRM_DEBUG_ATOMIC("Added [PLANE:%d:%s] %p state to %p\n",
651 			 plane->base.id, plane->name, plane_state, state);
652 
653 	if (plane_state->crtc) {
654 		struct drm_crtc_state *crtc_state;
655 
656 		crtc_state = drm_atomic_get_crtc_state(state,
657 						       plane_state->crtc);
658 		if (IS_ERR(crtc_state))
659 			return ERR_CAST(crtc_state);
660 	}
661 
662 	return plane_state;
663 }
664 EXPORT_SYMBOL(drm_atomic_get_plane_state);
665 
666 /**
667  * drm_atomic_plane_set_property - set property on plane
668  * @plane: the drm plane to set a property on
669  * @state: the state object to update with the new property value
670  * @property: the property to set
671  * @val: the new property value
672  *
673  * Use this instead of calling plane->atomic_set_property directly.
674  * This function handles generic/core properties and calls out to
675  * driver's ->atomic_set_property() for driver properties.  To ensure
676  * consistent behavior you must call this function rather than the
677  * driver hook directly.
678  *
679  * RETURNS:
680  * Zero on success, error code on failure
681  */
682 int drm_atomic_plane_set_property(struct drm_plane *plane,
683 		struct drm_plane_state *state, struct drm_property *property,
684 		uint64_t val)
685 {
686 	struct drm_device *dev = plane->dev;
687 	struct drm_mode_config *config = &dev->mode_config;
688 
689 	if (property == config->prop_fb_id) {
690 		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev, val);
691 		drm_atomic_set_fb_for_plane(state, fb);
692 		if (fb)
693 			drm_framebuffer_unreference(fb);
694 	} else if (property == config->prop_crtc_id) {
695 		struct drm_crtc *crtc = drm_crtc_find(dev, val);
696 		return drm_atomic_set_crtc_for_plane(state, crtc);
697 	} else if (property == config->prop_crtc_x) {
698 		state->crtc_x = U642I64(val);
699 	} else if (property == config->prop_crtc_y) {
700 		state->crtc_y = U642I64(val);
701 	} else if (property == config->prop_crtc_w) {
702 		state->crtc_w = val;
703 	} else if (property == config->prop_crtc_h) {
704 		state->crtc_h = val;
705 	} else if (property == config->prop_src_x) {
706 		state->src_x = val;
707 	} else if (property == config->prop_src_y) {
708 		state->src_y = val;
709 	} else if (property == config->prop_src_w) {
710 		state->src_w = val;
711 	} else if (property == config->prop_src_h) {
712 		state->src_h = val;
713 	} else if (property == config->rotation_property) {
714 		state->rotation = val;
715 	} else if (plane->funcs->atomic_set_property) {
716 		return plane->funcs->atomic_set_property(plane, state,
717 				property, val);
718 	} else {
719 		return -EINVAL;
720 	}
721 
722 	return 0;
723 }
724 EXPORT_SYMBOL(drm_atomic_plane_set_property);
725 
726 /**
727  * drm_atomic_plane_get_property - get property value from plane state
728  * @plane: the drm plane to set a property on
729  * @state: the state object to get the property value from
730  * @property: the property to set
731  * @val: return location for the property value
732  *
733  * This function handles generic/core properties and calls out to
734  * driver's ->atomic_get_property() for driver properties.  To ensure
735  * consistent behavior you must call this function rather than the
736  * driver hook directly.
737  *
738  * RETURNS:
739  * Zero on success, error code on failure
740  */
741 static int
742 drm_atomic_plane_get_property(struct drm_plane *plane,
743 		const struct drm_plane_state *state,
744 		struct drm_property *property, uint64_t *val)
745 {
746 	struct drm_device *dev = plane->dev;
747 	struct drm_mode_config *config = &dev->mode_config;
748 
749 	if (property == config->prop_fb_id) {
750 		*val = (state->fb) ? state->fb->base.id : 0;
751 	} else if (property == config->prop_crtc_id) {
752 		*val = (state->crtc) ? state->crtc->base.id : 0;
753 	} else if (property == config->prop_crtc_x) {
754 		*val = I642U64(state->crtc_x);
755 	} else if (property == config->prop_crtc_y) {
756 		*val = I642U64(state->crtc_y);
757 	} else if (property == config->prop_crtc_w) {
758 		*val = state->crtc_w;
759 	} else if (property == config->prop_crtc_h) {
760 		*val = state->crtc_h;
761 	} else if (property == config->prop_src_x) {
762 		*val = state->src_x;
763 	} else if (property == config->prop_src_y) {
764 		*val = state->src_y;
765 	} else if (property == config->prop_src_w) {
766 		*val = state->src_w;
767 	} else if (property == config->prop_src_h) {
768 		*val = state->src_h;
769 	} else if (property == config->rotation_property) {
770 		*val = state->rotation;
771 	} else if (plane->funcs->atomic_get_property) {
772 		return plane->funcs->atomic_get_property(plane, state, property, val);
773 	} else {
774 		return -EINVAL;
775 	}
776 
777 	return 0;
778 }
779 
780 static bool
781 plane_switching_crtc(struct drm_atomic_state *state,
782 		     struct drm_plane *plane,
783 		     struct drm_plane_state *plane_state)
784 {
785 	if (!plane->state->crtc || !plane_state->crtc)
786 		return false;
787 
788 	if (plane->state->crtc == plane_state->crtc)
789 		return false;
790 
791 	/* This could be refined, but currently there's no helper or driver code
792 	 * to implement direct switching of active planes nor userspace to take
793 	 * advantage of more direct plane switching without the intermediate
794 	 * full OFF state.
795 	 */
796 	return true;
797 }
798 
799 /**
800  * drm_atomic_plane_check - check plane state
801  * @plane: plane to check
802  * @state: plane state to check
803  *
804  * Provides core sanity checks for plane state.
805  *
806  * RETURNS:
807  * Zero on success, error code on failure
808  */
809 static int drm_atomic_plane_check(struct drm_plane *plane,
810 		struct drm_plane_state *state)
811 {
812 	unsigned int fb_width, fb_height;
813 	int ret;
814 
815 	/* either *both* CRTC and FB must be set, or neither */
816 	if (WARN_ON(state->crtc && !state->fb)) {
817 		DRM_DEBUG_ATOMIC("CRTC set but no FB\n");
818 		return -EINVAL;
819 	} else if (WARN_ON(state->fb && !state->crtc)) {
820 		DRM_DEBUG_ATOMIC("FB set but no CRTC\n");
821 		return -EINVAL;
822 	}
823 
824 	/* if disabled, we don't care about the rest of the state: */
825 	if (!state->crtc)
826 		return 0;
827 
828 	/* Check whether this plane is usable on this CRTC */
829 	if (!(plane->possible_crtcs & drm_crtc_mask(state->crtc))) {
830 		DRM_DEBUG_ATOMIC("Invalid crtc for plane\n");
831 		return -EINVAL;
832 	}
833 
834 	/* Check whether this plane supports the fb pixel format. */
835 	ret = drm_plane_check_pixel_format(plane, state->fb->pixel_format);
836 	if (ret) {
837 		DRM_DEBUG_ATOMIC("Invalid pixel format %s\n",
838 				 drm_get_format_name(state->fb->pixel_format));
839 		return ret;
840 	}
841 
842 	/* Give drivers some help against integer overflows */
843 	if (state->crtc_w > INT_MAX ||
844 	    state->crtc_x > INT_MAX - (int32_t) state->crtc_w ||
845 	    state->crtc_h > INT_MAX ||
846 	    state->crtc_y > INT_MAX - (int32_t) state->crtc_h) {
847 		DRM_DEBUG_ATOMIC("Invalid CRTC coordinates %ux%u+%d+%d\n",
848 				 state->crtc_w, state->crtc_h,
849 				 state->crtc_x, state->crtc_y);
850 		return -ERANGE;
851 	}
852 
853 	fb_width = state->fb->width << 16;
854 	fb_height = state->fb->height << 16;
855 
856 	/* Make sure source coordinates are inside the fb. */
857 	if (state->src_w > fb_width ||
858 	    state->src_x > fb_width - state->src_w ||
859 	    state->src_h > fb_height ||
860 	    state->src_y > fb_height - state->src_h) {
861 		DRM_DEBUG_ATOMIC("Invalid source coordinates "
862 				 "%u.%06ux%u.%06u+%u.%06u+%u.%06u\n",
863 				 state->src_w >> 16, ((state->src_w & 0xffff) * 15625) >> 10,
864 				 state->src_h >> 16, ((state->src_h & 0xffff) * 15625) >> 10,
865 				 state->src_x >> 16, ((state->src_x & 0xffff) * 15625) >> 10,
866 				 state->src_y >> 16, ((state->src_y & 0xffff) * 15625) >> 10);
867 		return -ENOSPC;
868 	}
869 
870 	if (plane_switching_crtc(state->state, plane, state)) {
871 		DRM_DEBUG_ATOMIC("[PLANE:%d:%s] switching CRTC directly\n",
872 				 plane->base.id, plane->name);
873 		return -EINVAL;
874 	}
875 
876 	return 0;
877 }
878 
879 /**
880  * drm_atomic_get_connector_state - get connector state
881  * @state: global atomic state object
882  * @connector: connector to get state object for
883  *
884  * This function returns the connector state for the given connector,
885  * allocating it if needed. It will also grab the relevant connector lock to
886  * make sure that the state is consistent.
887  *
888  * Returns:
889  *
890  * Either the allocated state or the error code encoded into the pointer. When
891  * the error is EDEADLK then the w/w mutex code has detected a deadlock and the
892  * entire atomic sequence must be restarted. All other errors are fatal.
893  */
894 struct drm_connector_state *
895 drm_atomic_get_connector_state(struct drm_atomic_state *state,
896 			  struct drm_connector *connector)
897 {
898 	int ret, index;
899 	struct drm_mode_config *config = &connector->dev->mode_config;
900 	struct drm_connector_state *connector_state;
901 
902 	WARN_ON(!state->acquire_ctx);
903 
904 	ret = drm_modeset_lock(&config->connection_mutex, state->acquire_ctx);
905 	if (ret)
906 		return ERR_PTR(ret);
907 
908 	index = drm_connector_index(connector);
909 
910 	if (index >= state->num_connector) {
911 		struct __drm_connnectors_state *c;
912 		int alloc = max(index + 1, config->num_connector);
913 
914 		c = krealloc(state->connectors, alloc * sizeof(*state->connectors), GFP_KERNEL);
915 		if (!c)
916 			return ERR_PTR(-ENOMEM);
917 
918 		state->connectors = c;
919 		memset(&state->connectors[state->num_connector], 0,
920 		       sizeof(*state->connectors) * (alloc - state->num_connector));
921 
922 		state->num_connector = alloc;
923 	}
924 
925 	if (state->connectors[index].state)
926 		return state->connectors[index].state;
927 
928 	connector_state = connector->funcs->atomic_duplicate_state(connector);
929 	if (!connector_state)
930 		return ERR_PTR(-ENOMEM);
931 
932 	drm_connector_reference(connector);
933 	state->connectors[index].state = connector_state;
934 	state->connectors[index].ptr = connector;
935 	connector_state->state = state;
936 
937 	DRM_DEBUG_ATOMIC("Added [CONNECTOR:%d] %p state to %p\n",
938 			 connector->base.id, connector_state, state);
939 
940 	if (connector_state->crtc) {
941 		struct drm_crtc_state *crtc_state;
942 
943 		crtc_state = drm_atomic_get_crtc_state(state,
944 						       connector_state->crtc);
945 		if (IS_ERR(crtc_state))
946 			return ERR_CAST(crtc_state);
947 	}
948 
949 	return connector_state;
950 }
951 EXPORT_SYMBOL(drm_atomic_get_connector_state);
952 
953 /**
954  * drm_atomic_connector_set_property - set property on connector.
955  * @connector: the drm connector to set a property on
956  * @state: the state object to update with the new property value
957  * @property: the property to set
958  * @val: the new property value
959  *
960  * Use this instead of calling connector->atomic_set_property directly.
961  * This function handles generic/core properties and calls out to
962  * driver's ->atomic_set_property() for driver properties.  To ensure
963  * consistent behavior you must call this function rather than the
964  * driver hook directly.
965  *
966  * RETURNS:
967  * Zero on success, error code on failure
968  */
969 int drm_atomic_connector_set_property(struct drm_connector *connector,
970 		struct drm_connector_state *state, struct drm_property *property,
971 		uint64_t val)
972 {
973 	struct drm_device *dev = connector->dev;
974 	struct drm_mode_config *config = &dev->mode_config;
975 
976 	if (property == config->prop_crtc_id) {
977 		struct drm_crtc *crtc = drm_crtc_find(dev, val);
978 		return drm_atomic_set_crtc_for_connector(state, crtc);
979 	} else if (property == config->dpms_property) {
980 		/* setting DPMS property requires special handling, which
981 		 * is done in legacy setprop path for us.  Disallow (for
982 		 * now?) atomic writes to DPMS property:
983 		 */
984 		return -EINVAL;
985 	} else if (connector->funcs->atomic_set_property) {
986 		return connector->funcs->atomic_set_property(connector,
987 				state, property, val);
988 	} else {
989 		return -EINVAL;
990 	}
991 }
992 EXPORT_SYMBOL(drm_atomic_connector_set_property);
993 
994 /**
995  * drm_atomic_connector_get_property - get property value from connector state
996  * @connector: the drm connector to set a property on
997  * @state: the state object to get the property value from
998  * @property: the property to set
999  * @val: return location for the property value
1000  *
1001  * This function handles generic/core properties and calls out to
1002  * driver's ->atomic_get_property() for driver properties.  To ensure
1003  * consistent behavior you must call this function rather than the
1004  * driver hook directly.
1005  *
1006  * RETURNS:
1007  * Zero on success, error code on failure
1008  */
1009 static int
1010 drm_atomic_connector_get_property(struct drm_connector *connector,
1011 		const struct drm_connector_state *state,
1012 		struct drm_property *property, uint64_t *val)
1013 {
1014 	struct drm_device *dev = connector->dev;
1015 	struct drm_mode_config *config = &dev->mode_config;
1016 
1017 	if (property == config->prop_crtc_id) {
1018 		*val = (state->crtc) ? state->crtc->base.id : 0;
1019 	} else if (property == config->dpms_property) {
1020 		*val = connector->dpms;
1021 	} else if (connector->funcs->atomic_get_property) {
1022 		return connector->funcs->atomic_get_property(connector,
1023 				state, property, val);
1024 	} else {
1025 		return -EINVAL;
1026 	}
1027 
1028 	return 0;
1029 }
1030 
1031 int drm_atomic_get_property(struct drm_mode_object *obj,
1032 		struct drm_property *property, uint64_t *val)
1033 {
1034 	struct drm_device *dev = property->dev;
1035 	int ret;
1036 
1037 	switch (obj->type) {
1038 	case DRM_MODE_OBJECT_CONNECTOR: {
1039 		struct drm_connector *connector = obj_to_connector(obj);
1040 		WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
1041 		ret = drm_atomic_connector_get_property(connector,
1042 				connector->state, property, val);
1043 		break;
1044 	}
1045 	case DRM_MODE_OBJECT_CRTC: {
1046 		struct drm_crtc *crtc = obj_to_crtc(obj);
1047 		WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
1048 		ret = drm_atomic_crtc_get_property(crtc,
1049 				crtc->state, property, val);
1050 		break;
1051 	}
1052 	case DRM_MODE_OBJECT_PLANE: {
1053 		struct drm_plane *plane = obj_to_plane(obj);
1054 		WARN_ON(!drm_modeset_is_locked(&plane->mutex));
1055 		ret = drm_atomic_plane_get_property(plane,
1056 				plane->state, property, val);
1057 		break;
1058 	}
1059 	default:
1060 		ret = -EINVAL;
1061 		break;
1062 	}
1063 
1064 	return ret;
1065 }
1066 
1067 /**
1068  * drm_atomic_set_crtc_for_plane - set crtc for plane
1069  * @plane_state: the plane whose incoming state to update
1070  * @crtc: crtc to use for the plane
1071  *
1072  * Changing the assigned crtc for a plane requires us to grab the lock and state
1073  * for the new crtc, as needed. This function takes care of all these details
1074  * besides updating the pointer in the state object itself.
1075  *
1076  * Returns:
1077  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1078  * then the w/w mutex code has detected a deadlock and the entire atomic
1079  * sequence must be restarted. All other errors are fatal.
1080  */
1081 int
1082 drm_atomic_set_crtc_for_plane(struct drm_plane_state *plane_state,
1083 			      struct drm_crtc *crtc)
1084 {
1085 	struct drm_plane *plane = plane_state->plane;
1086 	struct drm_crtc_state *crtc_state;
1087 
1088 	if (plane_state->crtc) {
1089 		crtc_state = drm_atomic_get_crtc_state(plane_state->state,
1090 						       plane_state->crtc);
1091 		if (WARN_ON(IS_ERR(crtc_state)))
1092 			return PTR_ERR(crtc_state);
1093 
1094 		crtc_state->plane_mask &= ~(1 << drm_plane_index(plane));
1095 	}
1096 
1097 	plane_state->crtc = crtc;
1098 
1099 	if (crtc) {
1100 		crtc_state = drm_atomic_get_crtc_state(plane_state->state,
1101 						       crtc);
1102 		if (IS_ERR(crtc_state))
1103 			return PTR_ERR(crtc_state);
1104 		crtc_state->plane_mask |= (1 << drm_plane_index(plane));
1105 	}
1106 
1107 	if (crtc)
1108 		DRM_DEBUG_ATOMIC("Link plane state %p to [CRTC:%d:%s]\n",
1109 				 plane_state, crtc->base.id, crtc->name);
1110 	else
1111 		DRM_DEBUG_ATOMIC("Link plane state %p to [NOCRTC]\n",
1112 				 plane_state);
1113 
1114 	return 0;
1115 }
1116 EXPORT_SYMBOL(drm_atomic_set_crtc_for_plane);
1117 
1118 /**
1119  * drm_atomic_set_fb_for_plane - set framebuffer for plane
1120  * @plane_state: atomic state object for the plane
1121  * @fb: fb to use for the plane
1122  *
1123  * Changing the assigned framebuffer for a plane requires us to grab a reference
1124  * to the new fb and drop the reference to the old fb, if there is one. This
1125  * function takes care of all these details besides updating the pointer in the
1126  * state object itself.
1127  */
1128 void
1129 drm_atomic_set_fb_for_plane(struct drm_plane_state *plane_state,
1130 			    struct drm_framebuffer *fb)
1131 {
1132 	if (plane_state->fb)
1133 		drm_framebuffer_unreference(plane_state->fb);
1134 	if (fb)
1135 		drm_framebuffer_reference(fb);
1136 	plane_state->fb = fb;
1137 
1138 	if (fb)
1139 		DRM_DEBUG_ATOMIC("Set [FB:%d] for plane state %p\n",
1140 				 fb->base.id, plane_state);
1141 	else
1142 		DRM_DEBUG_ATOMIC("Set [NOFB] for plane state %p\n",
1143 				 plane_state);
1144 }
1145 EXPORT_SYMBOL(drm_atomic_set_fb_for_plane);
1146 
1147 /**
1148  * drm_atomic_set_crtc_for_connector - set crtc for connector
1149  * @conn_state: atomic state object for the connector
1150  * @crtc: crtc to use for the connector
1151  *
1152  * Changing the assigned crtc for a connector requires us to grab the lock and
1153  * state for the new crtc, as needed. This function takes care of all these
1154  * details besides updating the pointer in the state object itself.
1155  *
1156  * Returns:
1157  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1158  * then the w/w mutex code has detected a deadlock and the entire atomic
1159  * sequence must be restarted. All other errors are fatal.
1160  */
1161 int
1162 drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state,
1163 				  struct drm_crtc *crtc)
1164 {
1165 	struct drm_crtc_state *crtc_state;
1166 
1167 	if (conn_state->crtc == crtc)
1168 		return 0;
1169 
1170 	if (conn_state->crtc) {
1171 		crtc_state = drm_atomic_get_existing_crtc_state(conn_state->state,
1172 								conn_state->crtc);
1173 
1174 		crtc_state->connector_mask &=
1175 			~(1 << drm_connector_index(conn_state->connector));
1176 
1177 		drm_connector_unreference(conn_state->connector);
1178 		conn_state->crtc = NULL;
1179 	}
1180 
1181 	if (crtc) {
1182 		crtc_state = drm_atomic_get_crtc_state(conn_state->state, crtc);
1183 		if (IS_ERR(crtc_state))
1184 			return PTR_ERR(crtc_state);
1185 
1186 		crtc_state->connector_mask |=
1187 			1 << drm_connector_index(conn_state->connector);
1188 
1189 		drm_connector_reference(conn_state->connector);
1190 		conn_state->crtc = crtc;
1191 
1192 		DRM_DEBUG_ATOMIC("Link connector state %p to [CRTC:%d:%s]\n",
1193 				 conn_state, crtc->base.id, crtc->name);
1194 	} else {
1195 		DRM_DEBUG_ATOMIC("Link connector state %p to [NOCRTC]\n",
1196 				 conn_state);
1197 	}
1198 
1199 	return 0;
1200 }
1201 EXPORT_SYMBOL(drm_atomic_set_crtc_for_connector);
1202 
1203 /**
1204  * drm_atomic_add_affected_connectors - add connectors for crtc
1205  * @state: atomic state
1206  * @crtc: DRM crtc
1207  *
1208  * This function walks the current configuration and adds all connectors
1209  * currently using @crtc to the atomic configuration @state. Note that this
1210  * function must acquire the connection mutex. This can potentially cause
1211  * unneeded seralization if the update is just for the planes on one crtc. Hence
1212  * drivers and helpers should only call this when really needed (e.g. when a
1213  * full modeset needs to happen due to some change).
1214  *
1215  * Returns:
1216  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1217  * then the w/w mutex code has detected a deadlock and the entire atomic
1218  * sequence must be restarted. All other errors are fatal.
1219  */
1220 int
1221 drm_atomic_add_affected_connectors(struct drm_atomic_state *state,
1222 				   struct drm_crtc *crtc)
1223 {
1224 	struct drm_mode_config *config = &state->dev->mode_config;
1225 	struct drm_connector *connector;
1226 	struct drm_connector_state *conn_state;
1227 	int ret;
1228 
1229 	ret = drm_modeset_lock(&config->connection_mutex, state->acquire_ctx);
1230 	if (ret)
1231 		return ret;
1232 
1233 	DRM_DEBUG_ATOMIC("Adding all current connectors for [CRTC:%d:%s] to %p\n",
1234 			 crtc->base.id, crtc->name, state);
1235 
1236 	/*
1237 	 * Changed connectors are already in @state, so only need to look at the
1238 	 * current configuration.
1239 	 */
1240 	drm_for_each_connector(connector, state->dev) {
1241 		if (connector->state->crtc != crtc)
1242 			continue;
1243 
1244 		conn_state = drm_atomic_get_connector_state(state, connector);
1245 		if (IS_ERR(conn_state))
1246 			return PTR_ERR(conn_state);
1247 	}
1248 
1249 	return 0;
1250 }
1251 EXPORT_SYMBOL(drm_atomic_add_affected_connectors);
1252 
1253 /**
1254  * drm_atomic_add_affected_planes - add planes for crtc
1255  * @state: atomic state
1256  * @crtc: DRM crtc
1257  *
1258  * This function walks the current configuration and adds all planes
1259  * currently used by @crtc to the atomic configuration @state. This is useful
1260  * when an atomic commit also needs to check all currently enabled plane on
1261  * @crtc, e.g. when changing the mode. It's also useful when re-enabling a CRTC
1262  * to avoid special code to force-enable all planes.
1263  *
1264  * Since acquiring a plane state will always also acquire the w/w mutex of the
1265  * current CRTC for that plane (if there is any) adding all the plane states for
1266  * a CRTC will not reduce parallism of atomic updates.
1267  *
1268  * Returns:
1269  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1270  * then the w/w mutex code has detected a deadlock and the entire atomic
1271  * sequence must be restarted. All other errors are fatal.
1272  */
1273 int
1274 drm_atomic_add_affected_planes(struct drm_atomic_state *state,
1275 			       struct drm_crtc *crtc)
1276 {
1277 	struct drm_plane *plane;
1278 
1279 	WARN_ON(!drm_atomic_get_existing_crtc_state(state, crtc));
1280 
1281 	drm_for_each_plane_mask(plane, state->dev, crtc->state->plane_mask) {
1282 		struct drm_plane_state *plane_state =
1283 			drm_atomic_get_plane_state(state, plane);
1284 
1285 		if (IS_ERR(plane_state))
1286 			return PTR_ERR(plane_state);
1287 	}
1288 	return 0;
1289 }
1290 EXPORT_SYMBOL(drm_atomic_add_affected_planes);
1291 
1292 /**
1293  * drm_atomic_legacy_backoff - locking backoff for legacy ioctls
1294  * @state: atomic state
1295  *
1296  * This function should be used by legacy entry points which don't understand
1297  * -EDEADLK semantics. For simplicity this one will grab all modeset locks after
1298  * the slowpath completed.
1299  */
1300 void drm_atomic_legacy_backoff(struct drm_atomic_state *state)
1301 {
1302 	struct drm_device *dev = state->dev;
1303 	unsigned crtc_mask = 0;
1304 	struct drm_crtc *crtc;
1305 	int ret;
1306 	bool global = false;
1307 
1308 	drm_for_each_crtc(crtc, dev) {
1309 		if (crtc->acquire_ctx != state->acquire_ctx)
1310 			continue;
1311 
1312 		crtc_mask |= drm_crtc_mask(crtc);
1313 		crtc->acquire_ctx = NULL;
1314 	}
1315 
1316 	if (WARN_ON(dev->mode_config.acquire_ctx == state->acquire_ctx)) {
1317 		global = true;
1318 
1319 		dev->mode_config.acquire_ctx = NULL;
1320 	}
1321 
1322 retry:
1323 	drm_modeset_backoff(state->acquire_ctx);
1324 
1325 	ret = drm_modeset_lock_all_ctx(dev, state->acquire_ctx);
1326 	if (ret)
1327 		goto retry;
1328 
1329 	drm_for_each_crtc(crtc, dev)
1330 		if (drm_crtc_mask(crtc) & crtc_mask)
1331 			crtc->acquire_ctx = state->acquire_ctx;
1332 
1333 	if (global)
1334 		dev->mode_config.acquire_ctx = state->acquire_ctx;
1335 }
1336 EXPORT_SYMBOL(drm_atomic_legacy_backoff);
1337 
1338 /**
1339  * drm_atomic_check_only - check whether a given config would work
1340  * @state: atomic configuration to check
1341  *
1342  * Note that this function can return -EDEADLK if the driver needed to acquire
1343  * more locks but encountered a deadlock. The caller must then do the usual w/w
1344  * backoff dance and restart. All other errors are fatal.
1345  *
1346  * Returns:
1347  * 0 on success, negative error code on failure.
1348  */
1349 int drm_atomic_check_only(struct drm_atomic_state *state)
1350 {
1351 	struct drm_device *dev = state->dev;
1352 	struct drm_mode_config *config = &dev->mode_config;
1353 	struct drm_plane *plane;
1354 	struct drm_plane_state *plane_state;
1355 	struct drm_crtc *crtc;
1356 	struct drm_crtc_state *crtc_state;
1357 	int i, ret = 0;
1358 
1359 	DRM_DEBUG_ATOMIC("checking %p\n", state);
1360 
1361 	for_each_plane_in_state(state, plane, plane_state, i) {
1362 		ret = drm_atomic_plane_check(plane, plane_state);
1363 		if (ret) {
1364 			DRM_DEBUG_ATOMIC("[PLANE:%d:%s] atomic core check failed\n",
1365 					 plane->base.id, plane->name);
1366 			return ret;
1367 		}
1368 	}
1369 
1370 	for_each_crtc_in_state(state, crtc, crtc_state, i) {
1371 		ret = drm_atomic_crtc_check(crtc, crtc_state);
1372 		if (ret) {
1373 			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] atomic core check failed\n",
1374 					 crtc->base.id, crtc->name);
1375 			return ret;
1376 		}
1377 	}
1378 
1379 	if (config->funcs->atomic_check)
1380 		ret = config->funcs->atomic_check(state->dev, state);
1381 
1382 	if (!state->allow_modeset) {
1383 		for_each_crtc_in_state(state, crtc, crtc_state, i) {
1384 			if (drm_atomic_crtc_needs_modeset(crtc_state)) {
1385 				DRM_DEBUG_ATOMIC("[CRTC:%d:%s] requires full modeset\n",
1386 						 crtc->base.id, crtc->name);
1387 				return -EINVAL;
1388 			}
1389 		}
1390 	}
1391 
1392 	return ret;
1393 }
1394 EXPORT_SYMBOL(drm_atomic_check_only);
1395 
1396 /**
1397  * drm_atomic_commit - commit configuration atomically
1398  * @state: atomic configuration to check
1399  *
1400  * Note that this function can return -EDEADLK if the driver needed to acquire
1401  * more locks but encountered a deadlock. The caller must then do the usual w/w
1402  * backoff dance and restart. All other errors are fatal.
1403  *
1404  * Also note that on successful execution ownership of @state is transferred
1405  * from the caller of this function to the function itself. The caller must not
1406  * free or in any other way access @state. If the function fails then the caller
1407  * must clean up @state itself.
1408  *
1409  * Returns:
1410  * 0 on success, negative error code on failure.
1411  */
1412 int drm_atomic_commit(struct drm_atomic_state *state)
1413 {
1414 	struct drm_mode_config *config = &state->dev->mode_config;
1415 	int ret;
1416 
1417 	ret = drm_atomic_check_only(state);
1418 	if (ret)
1419 		return ret;
1420 
1421 	DRM_DEBUG_ATOMIC("commiting %p\n", state);
1422 
1423 	return config->funcs->atomic_commit(state->dev, state, false);
1424 }
1425 EXPORT_SYMBOL(drm_atomic_commit);
1426 
1427 /**
1428  * drm_atomic_nonblocking_commit - atomic&nonblocking configuration commit
1429  * @state: atomic configuration to check
1430  *
1431  * Note that this function can return -EDEADLK if the driver needed to acquire
1432  * more locks but encountered a deadlock. The caller must then do the usual w/w
1433  * backoff dance and restart. All other errors are fatal.
1434  *
1435  * Also note that on successful execution ownership of @state is transferred
1436  * from the caller of this function to the function itself. The caller must not
1437  * free or in any other way access @state. If the function fails then the caller
1438  * must clean up @state itself.
1439  *
1440  * Returns:
1441  * 0 on success, negative error code on failure.
1442  */
1443 int drm_atomic_nonblocking_commit(struct drm_atomic_state *state)
1444 {
1445 	struct drm_mode_config *config = &state->dev->mode_config;
1446 	int ret;
1447 
1448 	ret = drm_atomic_check_only(state);
1449 	if (ret)
1450 		return ret;
1451 
1452 	DRM_DEBUG_ATOMIC("commiting %p nonblocking\n", state);
1453 
1454 	return config->funcs->atomic_commit(state->dev, state, true);
1455 }
1456 EXPORT_SYMBOL(drm_atomic_nonblocking_commit);
1457 
1458 /*
1459  * The big monstor ioctl
1460  */
1461 
1462 static struct drm_pending_vblank_event *create_vblank_event(
1463 		struct drm_device *dev, struct drm_file *file_priv,
1464 		struct fence *fence, uint64_t user_data)
1465 {
1466 	struct drm_pending_vblank_event *e = NULL;
1467 	int ret;
1468 
1469 	e = kzalloc(sizeof *e, GFP_KERNEL);
1470 	if (!e)
1471 		return NULL;
1472 
1473 	e->event.base.type = DRM_EVENT_FLIP_COMPLETE;
1474 	e->event.base.length = sizeof(e->event);
1475 	e->event.user_data = user_data;
1476 
1477 	if (file_priv) {
1478 		ret = drm_event_reserve_init(dev, file_priv, &e->base,
1479 					     &e->event.base);
1480 		if (ret) {
1481 			kfree(e);
1482 			return NULL;
1483 		}
1484 	}
1485 
1486 	e->base.fence = fence;
1487 
1488 	return e;
1489 }
1490 
1491 static int atomic_set_prop(struct drm_atomic_state *state,
1492 		struct drm_mode_object *obj, struct drm_property *prop,
1493 		uint64_t prop_value)
1494 {
1495 	struct drm_mode_object *ref;
1496 	int ret;
1497 
1498 	if (!drm_property_change_valid_get(prop, prop_value, &ref))
1499 		return -EINVAL;
1500 
1501 	switch (obj->type) {
1502 	case DRM_MODE_OBJECT_CONNECTOR: {
1503 		struct drm_connector *connector = obj_to_connector(obj);
1504 		struct drm_connector_state *connector_state;
1505 
1506 		connector_state = drm_atomic_get_connector_state(state, connector);
1507 		if (IS_ERR(connector_state)) {
1508 			ret = PTR_ERR(connector_state);
1509 			break;
1510 		}
1511 
1512 		ret = drm_atomic_connector_set_property(connector,
1513 				connector_state, prop, prop_value);
1514 		break;
1515 	}
1516 	case DRM_MODE_OBJECT_CRTC: {
1517 		struct drm_crtc *crtc = obj_to_crtc(obj);
1518 		struct drm_crtc_state *crtc_state;
1519 
1520 		crtc_state = drm_atomic_get_crtc_state(state, crtc);
1521 		if (IS_ERR(crtc_state)) {
1522 			ret = PTR_ERR(crtc_state);
1523 			break;
1524 		}
1525 
1526 		ret = drm_atomic_crtc_set_property(crtc,
1527 				crtc_state, prop, prop_value);
1528 		break;
1529 	}
1530 	case DRM_MODE_OBJECT_PLANE: {
1531 		struct drm_plane *plane = obj_to_plane(obj);
1532 		struct drm_plane_state *plane_state;
1533 
1534 		plane_state = drm_atomic_get_plane_state(state, plane);
1535 		if (IS_ERR(plane_state)) {
1536 			ret = PTR_ERR(plane_state);
1537 			break;
1538 		}
1539 
1540 		ret = drm_atomic_plane_set_property(plane,
1541 				plane_state, prop, prop_value);
1542 		break;
1543 	}
1544 	default:
1545 		ret = -EINVAL;
1546 		break;
1547 	}
1548 
1549 	drm_property_change_valid_put(prop, ref);
1550 	return ret;
1551 }
1552 
1553 /**
1554  * drm_atomic_clean_old_fb -- Unset old_fb pointers and set plane->fb pointers.
1555  *
1556  * @dev: drm device to check.
1557  * @plane_mask: plane mask for planes that were updated.
1558  * @ret: return value, can be -EDEADLK for a retry.
1559  *
1560  * Before doing an update plane->old_fb is set to plane->fb,
1561  * but before dropping the locks old_fb needs to be set to NULL
1562  * and plane->fb updated. This is a common operation for each
1563  * atomic update, so this call is split off as a helper.
1564  */
1565 void drm_atomic_clean_old_fb(struct drm_device *dev,
1566 			     unsigned plane_mask,
1567 			     int ret)
1568 {
1569 	struct drm_plane *plane;
1570 
1571 	/* if succeeded, fixup legacy plane crtc/fb ptrs before dropping
1572 	 * locks (ie. while it is still safe to deref plane->state).  We
1573 	 * need to do this here because the driver entry points cannot
1574 	 * distinguish between legacy and atomic ioctls.
1575 	 */
1576 	drm_for_each_plane_mask(plane, dev, plane_mask) {
1577 		if (ret == 0) {
1578 			struct drm_framebuffer *new_fb = plane->state->fb;
1579 			if (new_fb)
1580 				drm_framebuffer_reference(new_fb);
1581 			plane->fb = new_fb;
1582 			plane->crtc = plane->state->crtc;
1583 
1584 			if (plane->old_fb)
1585 				drm_framebuffer_unreference(plane->old_fb);
1586 		}
1587 		plane->old_fb = NULL;
1588 	}
1589 }
1590 EXPORT_SYMBOL(drm_atomic_clean_old_fb);
1591 
1592 int drm_mode_atomic_ioctl(struct drm_device *dev,
1593 			  void *data, struct drm_file *file_priv)
1594 {
1595 	struct drm_mode_atomic *arg = data;
1596 	uint32_t __user *objs_ptr = (uint32_t __user *)(unsigned long)(arg->objs_ptr);
1597 	uint32_t __user *count_props_ptr = (uint32_t __user *)(unsigned long)(arg->count_props_ptr);
1598 	uint32_t __user *props_ptr = (uint32_t __user *)(unsigned long)(arg->props_ptr);
1599 	uint64_t __user *prop_values_ptr = (uint64_t __user *)(unsigned long)(arg->prop_values_ptr);
1600 	unsigned int copied_objs, copied_props;
1601 	struct drm_atomic_state *state;
1602 	struct drm_modeset_acquire_ctx ctx;
1603 	struct drm_plane *plane;
1604 	struct drm_crtc *crtc;
1605 	struct drm_crtc_state *crtc_state;
1606 	unsigned plane_mask;
1607 	int ret = 0;
1608 	unsigned int i, j;
1609 
1610 	/* disallow for drivers not supporting atomic: */
1611 	if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
1612 		return -EINVAL;
1613 
1614 	/* disallow for userspace that has not enabled atomic cap (even
1615 	 * though this may be a bit overkill, since legacy userspace
1616 	 * wouldn't know how to call this ioctl)
1617 	 */
1618 	if (!file_priv->atomic)
1619 		return -EINVAL;
1620 
1621 	if (arg->flags & ~DRM_MODE_ATOMIC_FLAGS)
1622 		return -EINVAL;
1623 
1624 	if (arg->reserved)
1625 		return -EINVAL;
1626 
1627 	if ((arg->flags & DRM_MODE_PAGE_FLIP_ASYNC) &&
1628 			!dev->mode_config.async_page_flip)
1629 		return -EINVAL;
1630 
1631 	/* can't test and expect an event at the same time. */
1632 	if ((arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) &&
1633 			(arg->flags & DRM_MODE_PAGE_FLIP_EVENT))
1634 		return -EINVAL;
1635 
1636 	drm_modeset_acquire_init(&ctx, 0);
1637 
1638 	state = drm_atomic_state_alloc(dev);
1639 	if (!state)
1640 		return -ENOMEM;
1641 
1642 	state->acquire_ctx = &ctx;
1643 	state->allow_modeset = !!(arg->flags & DRM_MODE_ATOMIC_ALLOW_MODESET);
1644 
1645 retry:
1646 	plane_mask = 0;
1647 	copied_objs = 0;
1648 	copied_props = 0;
1649 
1650 	for (i = 0; i < arg->count_objs; i++) {
1651 		uint32_t obj_id, count_props;
1652 		struct drm_mode_object *obj;
1653 
1654 		if (get_user(obj_id, objs_ptr + copied_objs)) {
1655 			ret = -EFAULT;
1656 			goto out;
1657 		}
1658 
1659 		obj = drm_mode_object_find(dev, obj_id, DRM_MODE_OBJECT_ANY);
1660 		if (!obj) {
1661 			ret = -ENOENT;
1662 			goto out;
1663 		}
1664 
1665 		if (!obj->properties) {
1666 			drm_mode_object_unreference(obj);
1667 			ret = -ENOENT;
1668 			goto out;
1669 		}
1670 
1671 		if (get_user(count_props, count_props_ptr + copied_objs)) {
1672 			drm_mode_object_unreference(obj);
1673 			ret = -EFAULT;
1674 			goto out;
1675 		}
1676 
1677 		copied_objs++;
1678 
1679 		for (j = 0; j < count_props; j++) {
1680 			uint32_t prop_id;
1681 			uint64_t prop_value;
1682 			struct drm_property *prop;
1683 
1684 			if (get_user(prop_id, props_ptr + copied_props)) {
1685 				drm_mode_object_unreference(obj);
1686 				ret = -EFAULT;
1687 				goto out;
1688 			}
1689 
1690 			prop = drm_property_find(dev, prop_id);
1691 			if (!prop) {
1692 				drm_mode_object_unreference(obj);
1693 				ret = -ENOENT;
1694 				goto out;
1695 			}
1696 
1697 			if (copy_from_user(&prop_value,
1698 					   prop_values_ptr + copied_props,
1699 					   sizeof(prop_value))) {
1700 				drm_mode_object_unreference(obj);
1701 				ret = -EFAULT;
1702 				goto out;
1703 			}
1704 
1705 			ret = atomic_set_prop(state, obj, prop, prop_value);
1706 			if (ret) {
1707 				drm_mode_object_unreference(obj);
1708 				goto out;
1709 			}
1710 
1711 			copied_props++;
1712 		}
1713 
1714 		if (obj->type == DRM_MODE_OBJECT_PLANE && count_props &&
1715 		    !(arg->flags & DRM_MODE_ATOMIC_TEST_ONLY)) {
1716 			plane = obj_to_plane(obj);
1717 			plane_mask |= (1 << drm_plane_index(plane));
1718 			plane->old_fb = plane->fb;
1719 		}
1720 		drm_mode_object_unreference(obj);
1721 	}
1722 
1723 	if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
1724 		for_each_crtc_in_state(state, crtc, crtc_state, i) {
1725 			struct drm_pending_vblank_event *e;
1726 
1727 			e = create_vblank_event(dev, file_priv, NULL,
1728 						arg->user_data);
1729 			if (!e) {
1730 				ret = -ENOMEM;
1731 				goto out;
1732 			}
1733 
1734 			crtc_state->event = e;
1735 		}
1736 	}
1737 
1738 	if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
1739 		/*
1740 		 * Unlike commit, check_only does not clean up state.
1741 		 * Below we call drm_atomic_state_free for it.
1742 		 */
1743 		ret = drm_atomic_check_only(state);
1744 	} else if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) {
1745 		ret = drm_atomic_nonblocking_commit(state);
1746 	} else {
1747 		ret = drm_atomic_commit(state);
1748 	}
1749 
1750 out:
1751 	drm_atomic_clean_old_fb(dev, plane_mask, ret);
1752 
1753 	if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
1754 		/*
1755 		 * TEST_ONLY and PAGE_FLIP_EVENT are mutually exclusive,
1756 		 * if they weren't, this code should be called on success
1757 		 * for TEST_ONLY too.
1758 		 */
1759 
1760 		for_each_crtc_in_state(state, crtc, crtc_state, i) {
1761 			if (!crtc_state->event)
1762 				continue;
1763 
1764 			drm_event_cancel_free(dev, &crtc_state->event->base);
1765 		}
1766 	}
1767 
1768 	if (ret == -EDEADLK) {
1769 		drm_atomic_state_clear(state);
1770 		drm_modeset_backoff(&ctx);
1771 		goto retry;
1772 	}
1773 
1774 	if (ret || arg->flags & DRM_MODE_ATOMIC_TEST_ONLY)
1775 		drm_atomic_state_free(state);
1776 
1777 	drm_modeset_drop_locks(&ctx);
1778 	drm_modeset_acquire_fini(&ctx);
1779 
1780 	return ret;
1781 }
1782