summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/drm_plane_helper.c
blob: f88f681615193040e5375ecaca9c05c4590267d0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
/*
 * Copyright (C) 2014 Intel Corporation
 *
 * DRM universal plane helper functions
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <linux/list.h>
#include <drm/drmP.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_rect.h>
#include <drm/drm_atomic.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_encoder.h>
#include <drm/drm_atomic_helper.h>

#define SUBPIXEL_MASK 0xffff

/**
 * DOC: overview
 *
 * This helper library has two parts. The first part has support to implement
 * primary plane support on top of the normal CRTC configuration interface.
 * Since the legacy &drm_mode_config_funcs.set_config interface ties the primary
 * plane together with the CRTC state this does not allow userspace to disable
 * the primary plane itself.  To avoid too much duplicated code use
 * drm_plane_helper_check_update() which can be used to enforce the same
 * restrictions as primary planes had thus. The default primary plane only
 * expose XRBG8888 and ARGB8888 as valid pixel formats for the attached
 * framebuffer.
 *
 * Drivers are highly recommended to implement proper support for primary
 * planes, and newly merged drivers must not rely upon these transitional
 * helpers.
 *
 * The second part also implements transitional helpers which allow drivers to
 * gradually switch to the atomic helper infrastructure for plane updates. Once
 * that switch is complete drivers shouldn't use these any longer, instead using
 * the proper legacy implementations for update and disable plane hooks provided
 * by the atomic helpers.
 *
 * Again drivers are strongly urged to switch to the new interfaces.
 *
 * The plane helpers share the function table structures with other helpers,
 * specifically also the atomic helpers. See &struct drm_plane_helper_funcs for
 * the details.
 */

/*
 * Returns the connectors currently associated with a CRTC.  This function
 * should be called twice:  once with a NULL connector list to retrieve
 * the list size, and once with the properly allocated list to be filled in.
 */
static int get_connectors_for_crtc(struct drm_crtc *crtc,
				   struct drm_connector **connector_list,
				   int num_connectors)
{
	struct drm_device *dev = crtc->dev;
	struct drm_connector *connector;
	struct drm_connector_list_iter conn_iter;
	int count = 0;

	/*
	 * Note: Once we change the plane hooks to more fine-grained locking we
	 * need to grab the connection_mutex here to be able to make these
	 * checks.
	 */
	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));

	drm_connector_list_iter_begin(dev, &conn_iter);
	drm_for_each_connector_iter(connector, &conn_iter) {
		if (connector->encoder && connector->encoder->crtc == crtc) {
			if (connector_list != NULL && count < num_connectors)
				*(connector_list++) = connector;

			count++;
		}
	}
	drm_connector_list_iter_end(&conn_iter);

	return count;
}

/**
 * drm_plane_helper_check_update() - Check plane update for validity
 * @plane: plane object to update
 * @crtc: owning CRTC of owning plane
 * @fb: framebuffer to flip onto plane
 * @src: source coordinates in 16.16 fixed point
 * @dst: integer destination coordinates
 * @rotation: plane rotation
 * @min_scale: minimum @src:@dest scaling factor in 16.16 fixed point
 * @max_scale: maximum @src:@dest scaling factor in 16.16 fixed point
 * @can_position: is it legal to position the plane such that it
 *                doesn't cover the entire crtc?  This will generally
 *                only be false for primary planes.
 * @can_update_disabled: can the plane be updated while the crtc
 *                       is disabled?
 * @visible: output parameter indicating whether plane is still visible after
 *           clipping
 *
 * Checks that a desired plane update is valid.  Drivers that provide
 * their own plane handling rather than helper-provided implementations may
 * still wish to call this function to avoid duplication of error checking
 * code.
 *
 * RETURNS:
 * Zero if update appears valid, error code on failure
 */
int drm_plane_helper_check_update(struct drm_plane *plane,
				  struct drm_crtc *crtc,
				  struct drm_framebuffer *fb,
				  struct drm_rect *src,
				  struct drm_rect *dst,
				  unsigned int rotation,
				  int min_scale,
				  int max_scale,
				  bool can_position,
				  bool can_update_disabled,
				  bool *visible)
{
	struct drm_plane_state plane_state = {
		.plane = plane,
		.crtc = crtc,
		.fb = fb,
		.src_x = src->x1,
		.src_y = src->y1,
		.src_w = drm_rect_width(src),
		.src_h = drm_rect_height(src),
		.crtc_x = dst->x1,
		.crtc_y = dst->y1,
		.crtc_w = drm_rect_width(dst),
		.crtc_h = drm_rect_height(dst),
		.rotation = rotation,
		.visible = *visible,
	};
	struct drm_crtc_state crtc_state = {
		.crtc = crtc,
		.enable = crtc->enabled,
		.mode = crtc->mode,
	};
	int ret;

	ret = drm_atomic_helper_check_plane_state(&plane_state, &crtc_state,
						  min_scale, max_scale,
						  can_position,
						  can_update_disabled);
	if (ret)
		return ret;

	*src = plane_state.src;
	*dst = plane_state.dst;
	*visible = plane_state.visible;

	return 0;
}
EXPORT_SYMBOL(drm_plane_helper_check_update);

/**
 * drm_primary_helper_update() - Helper for primary plane update
 * @plane: plane object to update
 * @crtc: owning CRTC of owning plane
 * @fb: framebuffer to flip onto plane
 * @crtc_x: x offset of primary plane on crtc
 * @crtc_y: y offset of primary plane on crtc
 * @crtc_w: width of primary plane rectangle on crtc
 * @crtc_h: height of primary plane rectangle on crtc
 * @src_x: x offset of @fb for panning
 * @src_y: y offset of @fb for panning
 * @src_w: width of source rectangle in @fb
 * @src_h: height of source rectangle in @fb
 * @ctx: lock acquire context, not used here
 *
 * Provides a default plane update handler for primary planes.  This is handler
 * is called in response to a userspace SetPlane operation on the plane with a
 * non-NULL framebuffer.  We call the driver's modeset handler to update the
 * framebuffer.
 *
 * SetPlane() on a primary plane of a disabled CRTC is not supported, and will
 * return an error.
 *
 * Note that we make some assumptions about hardware limitations that may not be
 * true for all hardware --
 *
 * 1. Primary plane cannot be repositioned.
 * 2. Primary plane cannot be scaled.
 * 3. Primary plane must cover the entire CRTC.
 * 4. Subpixel positioning is not supported.
 *
 * Drivers for hardware that don't have these restrictions can provide their
 * own implementation rather than using this helper.
 *
 * RETURNS:
 * Zero on success, error code on failure
 */
int drm_primary_helper_update(struct drm_plane *plane, struct drm_crtc *crtc,
			      struct drm_framebuffer *fb,
			      int crtc_x, int crtc_y,
			      unsigned int crtc_w, unsigned int crtc_h,
			      uint32_t src_x, uint32_t src_y,
			      uint32_t src_w, uint32_t src_h,
			      struct drm_modeset_acquire_ctx *ctx)
{
	struct drm_mode_set set = {
		.crtc = crtc,
		.fb = fb,
		.mode = &crtc->mode,
		.x = src_x >> 16,
		.y = src_y >> 16,
	};
	struct drm_rect src = {
		.x1 = src_x,
		.y1 = src_y,
		.x2 = src_x + src_w,
		.y2 = src_y + src_h,
	};
	struct drm_rect dest = {
		.x1 = crtc_x,
		.y1 = crtc_y,
		.x2 = crtc_x + crtc_w,
		.y2 = crtc_y + crtc_h,
	};
	struct drm_connector **connector_list;
	int num_connectors, ret;
	bool visible;

	ret = drm_plane_helper_check_update(plane, crtc, fb,
					    &src, &dest,
					    DRM_MODE_ROTATE_0,
					    DRM_PLANE_HELPER_NO_SCALING,
					    DRM_PLANE_HELPER_NO_SCALING,
					    false, false, &visible);
	if (ret)
		return ret;

	if (!visible)
		/*
		 * Primary plane isn't visible.  Note that unless a driver
		 * provides their own disable function, this will just
		 * wind up returning -EINVAL to userspace.
		 */
		return plane->funcs->disable_plane(plane, ctx);

	/* Find current connectors for CRTC */
	num_connectors = get_connectors_for_crtc(crtc, NULL, 0);
	BUG_ON(num_connectors == 0);
	connector_list = kcalloc(num_connectors, sizeof(*connector_list),
				 GFP_KERNEL);
	if (!connector_list)
		return -ENOMEM;
	get_connectors_for_crtc(crtc, connector_list, num_connectors);

	set.connectors = connector_list;
	set.num_connectors = num_connectors;

	/*
	 * We call set_config() directly here rather than using
	 * drm_mode_set_config_internal.  We're reprogramming the same
	 * connectors that were already in use, so we shouldn't need the extra
	 * cross-CRTC fb refcounting to accomodate stealing connectors.
	 * drm_mode_setplane() already handles the basic refcounting for the
	 * framebuffers involved in this operation.
	 */
	ret = crtc->funcs->set_config(&set, ctx);

	kfree(connector_list);
	return ret;
}
EXPORT_SYMBOL(drm_primary_helper_update);

/**
 * drm_primary_helper_disable() - Helper for primary plane disable
 * @plane: plane to disable
 * @ctx: lock acquire context, not used here
 *
 * Provides a default plane disable handler for primary planes.  This is handler
 * is called in response to a userspace SetPlane operation on the plane with a
 * NULL framebuffer parameter.  It unconditionally fails the disable call with
 * -EINVAL the only way to disable the primary plane without driver support is
 * to disable the entire CRTC. Which does not match the plane
 * &drm_plane_funcs.disable_plane hook.
 *
 * Note that some hardware may be able to disable the primary plane without
 * disabling the whole CRTC.  Drivers for such hardware should provide their
 * own disable handler that disables just the primary plane (and they'll likely
 * need to provide their own update handler as well to properly re-enable a
 * disabled primary plane).
 *
 * RETURNS:
 * Unconditionally returns -EINVAL.
 */
int drm_primary_helper_disable(struct drm_plane *plane,
			       struct drm_modeset_acquire_ctx *ctx)
{
	return -EINVAL;
}
EXPORT_SYMBOL(drm_primary_helper_disable);

/**
 * drm_primary_helper_destroy() - Helper for primary plane destruction
 * @plane: plane to destroy
 *
 * Provides a default plane destroy handler for primary planes.  This handler
 * is called during CRTC destruction.  We disable the primary plane, remove
 * it from the DRM plane list, and deallocate the plane structure.
 */
void drm_primary_helper_destroy(struct drm_plane *plane)
{
	drm_plane_cleanup(plane);
	kfree(plane);
}
EXPORT_SYMBOL(drm_primary_helper_destroy);

const struct drm_plane_funcs drm_primary_helper_funcs = {
	.update_plane = drm_primary_helper_update,
	.disable_plane = drm_primary_helper_disable,
	.destroy = drm_primary_helper_destroy,
};
EXPORT_SYMBOL(drm_primary_helper_funcs);

int drm_plane_helper_commit(struct drm_plane *plane,
			    struct drm_plane_state *plane_state,
			    struct drm_framebuffer *old_fb)
{
	const struct drm_plane_helper_funcs *plane_funcs;
	struct drm_crtc *crtc[2];
	const struct drm_crtc_helper_funcs *crtc_funcs[2];
	int i, ret = 0;

	plane_funcs = plane->helper_private;

	/* Since this is a transitional helper we can't assume that plane->state
	 * is always valid. Hence we need to use plane->crtc instead of
	 * plane->state->crtc as the old crtc. */
	crtc[0] = plane->crtc;
	crtc[1] = crtc[0] != plane_state->crtc ? plane_state->crtc : NULL;

	for (i = 0; i < 2; i++)
		crtc_funcs[i] = crtc[i] ? crtc[i]->helper_private : NULL;

	if (plane_funcs->atomic_check) {
		ret = plane_funcs->atomic_check(plane, plane_state);
		if (ret)
			goto out;
	}

	if (plane_funcs->prepare_fb && plane_state->fb != old_fb) {
		ret = plane_funcs->prepare_fb(plane,
					      plane_state);
		if (ret)
			goto out;
	}

	/* Point of no return, commit sw state. */
	swap(plane->state, plane_state);

	for (i = 0; i < 2; i++) {
		if (crtc_funcs[i] && crtc_funcs[i]->atomic_begin)
			crtc_funcs[i]->atomic_begin(crtc[i], crtc[i]->state);
	}

	/*
	 * Drivers may optionally implement the ->atomic_disable callback, so
	 * special-case that here.
	 */
	if (drm_atomic_plane_disabling(plane_state, plane->state) &&
	    plane_funcs->atomic_disable)
		plane_funcs->atomic_disable(plane, plane_state);
	else
		plane_funcs->atomic_update(plane, plane_state);

	for (i = 0; i < 2; i++) {
		if (crtc_funcs[i] && crtc_funcs[i]->atomic_flush)
			crtc_funcs[i]->atomic_flush(crtc[i], crtc[i]->state);
	}

	/*
	 * If we only moved the plane and didn't change fb's, there's no need to
	 * wait for vblank.
	 */
	if (plane->state->fb == old_fb)
		goto out;

	for (i = 0; i < 2; i++) {
		if (!crtc[i])
			continue;

		if (crtc[i]->cursor == plane)
			continue;

		/* There's no other way to figure out whether the crtc is running. */
		ret = drm_crtc_vblank_get(crtc[i]);
		if (ret == 0) {
			drm_crtc_wait_one_vblank(crtc[i]);
			drm_crtc_vblank_put(crtc[i]);
		}

		ret = 0;
	}

	if (plane_funcs->cleanup_fb)
		plane_funcs->cleanup_fb(plane, plane_state);
out:
	if (plane->funcs->atomic_destroy_state)
		plane->funcs->atomic_destroy_state(plane, plane_state);
	else
		drm_atomic_helper_plane_destroy_state(plane, plane_state);

	return ret;
}

/**
 * drm_plane_helper_update() - Transitional helper for plane update
 * @plane: plane object to update
 * @crtc: owning CRTC of owning plane
 * @fb: framebuffer to flip onto plane
 * @crtc_x: x offset of primary plane on crtc
 * @crtc_y: y offset of primary plane on crtc
 * @crtc_w: width of primary plane rectangle on crtc
 * @crtc_h: height of primary plane rectangle on crtc
 * @src_x: x offset of @fb for panning
 * @src_y: y offset of @fb for panning
 * @src_w: width of source rectangle in @fb
 * @src_h: height of source rectangle in @fb
 *
 * Provides a default plane update handler using the atomic plane update
 * functions. It is fully left to the driver to check plane constraints and
 * handle corner-cases like a fully occluded or otherwise invisible plane.
 *
 * This is useful for piecewise transitioning of a driver to the atomic helpers.
 *
 * RETURNS:
 * Zero on success, error code on failure
 */
int drm_plane_helper_update(struct drm_plane *plane, struct drm_crtc *crtc,
			    struct drm_framebuffer *fb,
			    int crtc_x, int crtc_y,
			    unsigned int crtc_w, unsigned int crtc_h,
			    uint32_t src_x, uint32_t src_y,
			    uint32_t src_w, uint32_t src_h)
{
	struct drm_plane_state *plane_state;

	if (plane->funcs->atomic_duplicate_state)
		plane_state = plane->funcs->atomic_duplicate_state(plane);
	else {
		if (!plane->state)
			drm_atomic_helper_plane_reset(plane);

		plane_state = drm_atomic_helper_plane_duplicate_state(plane);
	}
	if (!plane_state)
		return -ENOMEM;
	plane_state->plane = plane;

	plane_state->crtc = crtc;
	drm_atomic_set_fb_for_plane(plane_state, fb);
	plane_state->crtc_x = crtc_x;
	plane_state->crtc_y = crtc_y;
	plane_state->crtc_h = crtc_h;
	plane_state->crtc_w = crtc_w;
	plane_state->src_x = src_x;
	plane_state->src_y = src_y;
	plane_state->src_h = src_h;
	plane_state->src_w = src_w;

	return drm_plane_helper_commit(plane, plane_state, plane->fb);
}
EXPORT_SYMBOL(drm_plane_helper_update);

/**
 * drm_plane_helper_disable() - Transitional helper for plane disable
 * @plane: plane to disable
 *
 * Provides a default plane disable handler using the atomic plane update
 * functions. It is fully left to the driver to check plane constraints and
 * handle corner-cases like a fully occluded or otherwise invisible plane.
 *
 * This is useful for piecewise transitioning of a driver to the atomic helpers.
 *
 * RETURNS:
 * Zero on success, error code on failure
 */
int drm_plane_helper_disable(struct drm_plane *plane)
{
	struct drm_plane_state *plane_state;

	/* crtc helpers love to call disable functions for already disabled hw
	 * functions. So cope with that. */
	if (!plane->crtc)
		return 0;

	if (plane->funcs->atomic_duplicate_state)
		plane_state = plane->funcs->atomic_duplicate_state(plane);
	else {
		if (!plane->state)
			drm_atomic_helper_plane_reset(plane);

		plane_state = drm_atomic_helper_plane_duplicate_state(plane);
	}
	if (!plane_state)
		return -ENOMEM;
	plane_state->plane = plane;

	plane_state->crtc = NULL;
	drm_atomic_set_fb_for_plane(plane_state, NULL);

	return drm_plane_helper_commit(plane, plane_state, plane->fb);
}
EXPORT_SYMBOL(drm_plane_helper_disable);