1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /**************************************************************************
3 *
4 * Copyright (c) 2018 VMware, Inc., Palo Alto, CA., USA
5 * All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
17 * of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
25 * USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 * Authors:
28 * Deepak Rawat <drawat@vmware.com>
29 * Rob Clark <robdclark@gmail.com>
30 *
31 **************************************************************************/
32
33 #include <drm/drm_atomic.h>
34 #include <drm/drm_damage_helper.h>
35 #include <drm/drm_device.h>
36
37 /**
38 * DOC: overview
39 *
40 * FB_DAMAGE_CLIPS is an optional plane property which provides a means to
41 * specify a list of damage rectangles on a plane in framebuffer coordinates of
42 * the framebuffer attached to the plane. In current context damage is the area
43 * of plane framebuffer that has changed since last plane update (also called
44 * page-flip), irrespective of whether currently attached framebuffer is same as
45 * framebuffer attached during last plane update or not.
46 *
47 * FB_DAMAGE_CLIPS is a hint to kernel which could be helpful for some drivers
48 * to optimize internally especially for virtual devices where each framebuffer
49 * change needs to be transmitted over network, usb, etc.
50 *
51 * Since FB_DAMAGE_CLIPS is a hint so it is an optional property. User-space can
52 * ignore damage clips property and in that case driver will do a full plane
53 * update. In case damage clips are provided then it is guaranteed that the area
54 * inside damage clips will be updated to plane. For efficiency driver can do
55 * full update or can update more than specified in damage clips. Since driver
56 * is free to read more, user-space must always render the entire visible
57 * framebuffer. Otherwise there can be corruptions. Also, if a user-space
58 * provides damage clips which doesn't encompass the actual damage to
59 * framebuffer (since last plane update) can result in incorrect rendering.
60 *
61 * FB_DAMAGE_CLIPS is a blob property with the layout of blob data is simply an
62 * array of &drm_mode_rect. Unlike plane &drm_plane_state.src coordinates,
63 * damage clips are not in 16.16 fixed point. Similar to plane src in
64 * framebuffer, damage clips cannot be negative. In damage clip, x1/y1 are
65 * inclusive and x2/y2 are exclusive. While kernel does not error for overlapped
66 * damage clips, it is strongly discouraged.
67 *
68 * Drivers that are interested in damage interface for plane should enable
69 * FB_DAMAGE_CLIPS property by calling drm_plane_enable_fb_damage_clips().
70 * Drivers implementing damage can use drm_atomic_helper_damage_iter_init() and
71 * drm_atomic_helper_damage_iter_next() helper iterator function to get damage
72 * rectangles clipped to &drm_plane_state.src.
73 */
74
75 static void convert_clip_rect_to_rect(const struct drm_clip_rect *src,
76 struct drm_mode_rect *dest,
77 uint32_t num_clips, uint32_t src_inc)
78 {
79 while (num_clips > 0) {
80 dest->x1 = src->x1;
81 dest->y1 = src->y1;
82 dest->x2 = src->x2;
83 dest->y2 = src->y2;
84 src += src_inc;
85 dest++;
86 num_clips--;
87 }
88 }
89
90 /**
91 * drm_plane_enable_fb_damage_clips - Enables plane fb damage clips property.
92 * @plane: Plane on which to enable damage clips property.
93 *
94 * This function lets driver to enable the damage clips property on a plane.
95 */
96 void drm_plane_enable_fb_damage_clips(struct drm_plane *plane)
97 {
98 struct drm_device *dev = plane->dev;
99 struct drm_mode_config *config = &dev->mode_config;
100
101 drm_object_attach_property(&plane->base, config->prop_fb_damage_clips,
102 0);
103 }
104 EXPORT_SYMBOL(drm_plane_enable_fb_damage_clips);
105
106 /**
107 * drm_atomic_helper_check_plane_damage - Verify plane damage on atomic_check.
108 * @state: The driver state object.
109 * @plane_state: Plane state for which to verify damage.
110 *
111 * This helper function makes sure that damage from plane state is discarded
112 * for full modeset. If there are more reasons a driver would want to do a full
113 * plane update rather than processing individual damage regions, then those
114 * cases should be taken care of here.
115 *
116 * Note that &drm_plane_state.fb_damage_clips == NULL in plane state means that
117 * full plane update should happen. It also ensure helper iterator will return
118 * &drm_plane_state.src as damage.
119 */
120 void drm_atomic_helper_check_plane_damage(struct drm_atomic_state *state,
121 struct drm_plane_state *plane_state)
122 {
123 struct drm_crtc_state *crtc_state;
124
125 if (plane_state->crtc) {
126 crtc_state = drm_atomic_get_new_crtc_state(state,
127 plane_state->crtc);
128
129 if (WARN_ON(!crtc_state))
130 return;
131
132 if (drm_atomic_crtc_needs_modeset(crtc_state)) {
133 drm_property_blob_put(plane_state->fb_damage_clips);
134 plane_state->fb_damage_clips = NULL;
135 }
136 }
137 }
138 EXPORT_SYMBOL(drm_atomic_helper_check_plane_damage);
139
140 /**
141 * drm_atomic_helper_dirtyfb - Helper for dirtyfb.
142 * @fb: DRM framebuffer.
143 * @file_priv: Drm file for the ioctl call.
144 * @flags: Dirty fb annotate flags.
145 * @color: Color for annotate fill.
146 * @clips: Dirty region.
147 * @num_clips: Count of clip in clips.
148 *
149 * A helper to implement &drm_framebuffer_funcs.dirty using damage interface
150 * during plane update. If num_clips is 0 then this helper will do a full plane
151 * update. This is the same behaviour expected by DIRTFB IOCTL.
152 *
153 * Note that this helper is blocking implementation. This is what current
154 * drivers and userspace expect in their DIRTYFB IOCTL implementation, as a way
155 * to rate-limit userspace and make sure its rendering doesn't get ahead of
156 * uploading new data too much.
157 *
158 * Return: Zero on success, negative errno on failure.
159 */
160 int drm_atomic_helper_dirtyfb(struct drm_framebuffer *fb,
161 struct drm_file *file_priv, unsigned int flags,
162 unsigned int color, struct drm_clip_rect *clips,
163 unsigned int num_clips)
164 {
165 struct drm_modeset_acquire_ctx ctx;
166 struct drm_property_blob *damage = NULL;
167 struct drm_mode_rect *rects = NULL;
168 struct drm_atomic_state *state;
169 struct drm_plane *plane;
170 int ret = 0;
171
172 /*
173 * When called from ioctl, we are interruptable, but not when called
174 * internally (ie. defio worker)
175 */
176 drm_modeset_acquire_init(&ctx,
177 file_priv ? DRM_MODESET_ACQUIRE_INTERRUPTIBLE : 0);
178
179 state = drm_atomic_state_alloc(fb->dev);
180 if (!state) {
181 ret = -ENOMEM;
182 goto out_drop_locks;
183 }
184 state->acquire_ctx = &ctx;
185
186 if (clips) {
187 uint32_t inc = 1;
188
189 if (flags & DRM_MODE_FB_DIRTY_ANNOTATE_COPY) {
190 inc = 2;
191 num_clips /= 2;
192 }
193
194 rects = kcalloc(num_clips, sizeof(*rects), GFP_KERNEL);
195 if (!rects) {
196 ret = -ENOMEM;
197 goto out;
198 }
199
200 convert_clip_rect_to_rect(clips, rects, num_clips, inc);
201 damage = drm_property_create_blob(fb->dev,
202 num_clips * sizeof(*rects),
203 rects);
204 if (IS_ERR(damage)) {
205 ret = PTR_ERR(damage);
206 damage = NULL;
207 goto out;
208 }
209 }
210
211 retry:
212 drm_for_each_plane(plane, fb->dev) {
213 struct drm_plane_state *plane_state;
214
215 ret = drm_modeset_lock(&plane->mutex, state->acquire_ctx);
216 if (ret)
217 goto out;
218
219 if (plane->state->fb != fb) {
220 drm_modeset_unlock(&plane->mutex);
221 continue;
222 }
223
224 plane_state = drm_atomic_get_plane_state(state, plane);
225 if (IS_ERR(plane_state)) {
226 ret = PTR_ERR(plane_state);
227 goto out;
228 }
229
230 drm_property_replace_blob(&plane_state->fb_damage_clips,
231 damage);
232 }
233
234 ret = drm_atomic_commit(state);
235
236 out:
237 if (ret == -EDEADLK) {
238 drm_atomic_state_clear(state);
239 ret = drm_modeset_backoff(&ctx);
240 if (!ret)
241 goto retry;
242 }
243
244 drm_property_blob_put(damage);
245 kfree(rects);
246 drm_atomic_state_put(state);
247
248 out_drop_locks:
249 drm_modeset_drop_locks(&ctx);
250 drm_modeset_acquire_fini(&ctx);
251
252 return ret;
253
254 }
255 EXPORT_SYMBOL(drm_atomic_helper_dirtyfb);
256
257 /**
258 * drm_atomic_helper_damage_iter_init - Initialize the damage iterator.
259 * @iter: The iterator to initialize.
260 * @old_state: Old plane state for validation.
261 * @state: Plane state from which to iterate the damage clips.
262 *
263 * Initialize an iterator, which clips plane damage
264 * &drm_plane_state.fb_damage_clips to plane &drm_plane_state.src. This iterator
265 * returns full plane src in case damage is not present because either
266 * user-space didn't sent or driver discarded it (it want to do full plane
267 * update). Currently this iterator returns full plane src in case plane src
268 * changed but that can be changed in future to return damage.
269 *
270 * For the case when plane is not visible or plane update should not happen the
271 * first call to iter_next will return false. Note that this helper use clipped
272 * &drm_plane_state.src, so driver calling this helper should have called
273 * drm_atomic_helper_check_plane_state() earlier.
274 */
275 void
276 drm_atomic_helper_damage_iter_init(struct drm_atomic_helper_damage_iter *iter,
277 const struct drm_plane_state *old_state,
278 const struct drm_plane_state *state)
279 {
280 memset(iter, 0, sizeof(*iter));
281
282 if (!state || !state->crtc || !state->fb || !state->visible)
283 return;
284
285 iter->clips = drm_helper_get_plane_damage_clips(state);
286 iter->num_clips = drm_plane_get_damage_clips_count(state);
287
288 /* Round down for x1/y1 and round up for x2/y2 to catch all pixels */
289 iter->plane_src.x1 = state->src.x1 >> 16;
290 iter->plane_src.y1 = state->src.y1 >> 16;
291 iter->plane_src.x2 = (state->src.x2 >> 16) + !!(state->src.x2 & 0xFFFF);
292 iter->plane_src.y2 = (state->src.y2 >> 16) + !!(state->src.y2 & 0xFFFF);
293
294 if (!iter->clips || !drm_rect_equals(&state->src, &old_state->src)) {
295 iter->clips = NULL;
296 iter->num_clips = 0;
297 iter->full_update = true;
298 }
299 }
300 EXPORT_SYMBOL(drm_atomic_helper_damage_iter_init);
301
302 /**
303 * drm_atomic_helper_damage_iter_next - Advance the damage iterator.
304 * @iter: The iterator to advance.
305 * @rect: Return a rectangle in fb coordinate clipped to plane src.
306 *
307 * Since plane src is in 16.16 fixed point and damage clips are whole number,
308 * this iterator round off clips that intersect with plane src. Round down for
309 * x1/y1 and round up for x2/y2 for the intersected coordinate. Similar rounding
310 * off for full plane src, in case it's returned as damage. This iterator will
311 * skip damage clips outside of plane src.
312 *
313 * Return: True if the output is valid, false if reached the end.
314 *
315 * If the first call to iterator next returns false then it means no need to
316 * update the plane.
317 */
318 bool
319 drm_atomic_helper_damage_iter_next(struct drm_atomic_helper_damage_iter *iter,
320 struct drm_rect *rect)
321 {
322 bool ret = false;
323
324 if (iter->full_update) {
325 *rect = iter->plane_src;
326 iter->full_update = false;
327 return true;
328 }
329
330 while (iter->curr_clip < iter->num_clips) {
331 *rect = iter->clips[iter->curr_clip];
332 iter->curr_clip++;
333
334 if (drm_rect_intersect(rect, &iter->plane_src)) {
335 ret = true;
336 break;
337 }
338 }
339
340 return ret;
341 }
342 EXPORT_SYMBOL(drm_atomic_helper_damage_iter_next);
343
344 /**
345 * drm_atomic_helper_damage_merged - Merged plane damage
346 * @old_state: Old plane state for validation.
347 * @state: Plane state from which to iterate the damage clips.
348 * @rect: Returns the merged damage rectangle
349 *
350 * This function merges any valid plane damage clips into one rectangle and
351 * returns it in @rect.
352 *
353 * For details see: drm_atomic_helper_damage_iter_init() and
354 * drm_atomic_helper_damage_iter_next().
355 *
356 * Returns:
357 * True if there is valid plane damage otherwise false.
358 */
359 bool drm_atomic_helper_damage_merged(const struct drm_plane_state *old_state,
360 struct drm_plane_state *state,
361 struct drm_rect *rect)
362 {
363 struct drm_atomic_helper_damage_iter iter;
364 struct drm_rect clip;
365 bool valid = false;
366
367 rect->x1 = INT_MAX;
368 rect->y1 = INT_MAX;
369 rect->x2 = 0;
370 rect->y2 = 0;
371
372 drm_atomic_helper_damage_iter_init(&iter, old_state, state);
373 drm_atomic_for_each_plane_damage(&iter, &clip) {
374 rect->x1 = min(rect->x1, clip.x1);
375 rect->y1 = min(rect->y1, clip.y1);
376 rect->x2 = max(rect->x2, clip.x2);
377 rect->y2 = max(rect->y2, clip.y2);
378 valid = true;
379 }
380
381 return valid;
382 }
383 EXPORT_SYMBOL(drm_atomic_helper_damage_merged);