Commit | Line | Data |
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2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
4c3dbb2c NT |
2 | /* |
3 | * drm gem framebuffer helper functions | |
4 | * | |
5 | * Copyright (C) 2017 Noralf Trønnes | |
4c3dbb2c NT |
6 | */ |
7 | ||
8 | #include <linux/dma-buf.h> | |
9 | #include <linux/dma-fence.h> | |
52791eee | 10 | #include <linux/dma-resv.h> |
4c3dbb2c NT |
11 | #include <linux/slab.h> |
12 | ||
4c3dbb2c | 13 | #include <drm/drm_atomic.h> |
72fdb40c | 14 | #include <drm/drm_atomic_uapi.h> |
dbd62e16 | 15 | #include <drm/drm_damage_helper.h> |
4c3dbb2c NT |
16 | #include <drm/drm_fb_helper.h> |
17 | #include <drm/drm_fourcc.h> | |
18 | #include <drm/drm_framebuffer.h> | |
19 | #include <drm/drm_gem.h> | |
20 | #include <drm/drm_gem_framebuffer_helper.h> | |
21 | #include <drm/drm_modeset_helper.h> | |
ccc3b2b3 | 22 | #include <drm/drm_simple_kms_helper.h> |
4c3dbb2c | 23 | |
55f7f727 AP |
24 | #define AFBC_HEADER_SIZE 16 |
25 | #define AFBC_TH_LAYOUT_ALIGNMENT 8 | |
26 | #define AFBC_HDR_ALIGN 64 | |
27 | #define AFBC_SUPERBLOCK_PIXELS 256 | |
28 | #define AFBC_SUPERBLOCK_ALIGNMENT 128 | |
29 | #define AFBC_TH_BODY_START_ALIGNMENT 4096 | |
30 | ||
4c3dbb2c NT |
31 | /** |
32 | * DOC: overview | |
33 | * | |
34 | * This library provides helpers for drivers that don't subclass | |
2e187b20 | 35 | * &drm_framebuffer and use &drm_gem_object for their backing storage. |
4c3dbb2c NT |
36 | * |
37 | * Drivers without additional needs to validate framebuffers can simply use | |
2e187b20 NT |
38 | * drm_gem_fb_create() and everything is wired up automatically. Other drivers |
39 | * can use all parts independently. | |
4c3dbb2c NT |
40 | */ |
41 | ||
42 | /** | |
2e187b20 NT |
43 | * drm_gem_fb_get_obj() - Get GEM object backing the framebuffer |
44 | * @fb: Framebuffer | |
45 | * @plane: Plane index | |
4c3dbb2c | 46 | * |
2e187b20 NT |
47 | * No additional reference is taken beyond the one that the &drm_frambuffer |
48 | * already holds. | |
49 | * | |
50 | * Returns: | |
51 | * Pointer to &drm_gem_object for the given framebuffer and plane index or NULL | |
52 | * if it does not exist. | |
4c3dbb2c NT |
53 | */ |
54 | struct drm_gem_object *drm_gem_fb_get_obj(struct drm_framebuffer *fb, | |
55 | unsigned int plane) | |
56 | { | |
57 | if (plane >= 4) | |
58 | return NULL; | |
59 | ||
60 | return fb->obj[plane]; | |
61 | } | |
62 | EXPORT_SYMBOL_GPL(drm_gem_fb_get_obj); | |
63 | ||
f2b816d7 AP |
64 | static int |
65 | drm_gem_fb_init(struct drm_device *dev, | |
66 | struct drm_framebuffer *fb, | |
4c3dbb2c NT |
67 | const struct drm_mode_fb_cmd2 *mode_cmd, |
68 | struct drm_gem_object **obj, unsigned int num_planes, | |
69 | const struct drm_framebuffer_funcs *funcs) | |
70 | { | |
4c3dbb2c NT |
71 | int ret, i; |
72 | ||
4c3dbb2c NT |
73 | drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd); |
74 | ||
75 | for (i = 0; i < num_planes; i++) | |
76 | fb->obj[i] = obj[i]; | |
77 | ||
78 | ret = drm_framebuffer_init(dev, fb, funcs); | |
13e3d941 | 79 | if (ret) |
24f03be4 | 80 | drm_err(dev, "Failed to init framebuffer: %d\n", ret); |
4c3dbb2c | 81 | |
f2b816d7 | 82 | return ret; |
4c3dbb2c NT |
83 | } |
84 | ||
85 | /** | |
86 | * drm_gem_fb_destroy - Free GEM backed framebuffer | |
2e187b20 | 87 | * @fb: Framebuffer |
4c3dbb2c NT |
88 | * |
89 | * Frees a GEM backed framebuffer with its backing buffer(s) and the structure | |
90 | * itself. Drivers can use this as their &drm_framebuffer_funcs->destroy | |
91 | * callback. | |
92 | */ | |
93 | void drm_gem_fb_destroy(struct drm_framebuffer *fb) | |
94 | { | |
95 | int i; | |
96 | ||
97 | for (i = 0; i < 4; i++) | |
98 | drm_gem_object_put_unlocked(fb->obj[i]); | |
99 | ||
100 | drm_framebuffer_cleanup(fb); | |
101 | kfree(fb); | |
102 | } | |
103 | EXPORT_SYMBOL(drm_gem_fb_destroy); | |
104 | ||
105 | /** | |
106 | * drm_gem_fb_create_handle - Create handle for GEM backed framebuffer | |
2e187b20 NT |
107 | * @fb: Framebuffer |
108 | * @file: DRM file to register the handle for | |
109 | * @handle: Pointer to return the created handle | |
4c3dbb2c | 110 | * |
2e187b20 | 111 | * This function creates a handle for the GEM object backing the framebuffer. |
4c3dbb2c | 112 | * Drivers can use this as their &drm_framebuffer_funcs->create_handle |
2e187b20 | 113 | * callback. The GETFB IOCTL calls into this callback. |
4c3dbb2c NT |
114 | * |
115 | * Returns: | |
116 | * 0 on success or a negative error code on failure. | |
117 | */ | |
118 | int drm_gem_fb_create_handle(struct drm_framebuffer *fb, struct drm_file *file, | |
119 | unsigned int *handle) | |
120 | { | |
121 | return drm_gem_handle_create(file, fb->obj[0], handle); | |
122 | } | |
123 | EXPORT_SYMBOL(drm_gem_fb_create_handle); | |
124 | ||
125 | /** | |
f2b816d7 AP |
126 | * drm_gem_fb_init_with_funcs() - Helper function for implementing |
127 | * &drm_mode_config_funcs.fb_create | |
128 | * callback in cases when the driver | |
129 | * allocates a subclass of | |
130 | * struct drm_framebuffer | |
4c3dbb2c | 131 | * @dev: DRM device |
f2b816d7 | 132 | * @fb: framebuffer object |
2e187b20 NT |
133 | * @file: DRM file that holds the GEM handle(s) backing the framebuffer |
134 | * @mode_cmd: Metadata from the userspace framebuffer creation request | |
4c3dbb2c NT |
135 | * @funcs: vtable to be used for the new framebuffer object |
136 | * | |
dbd62e16 NT |
137 | * This function can be used to set &drm_framebuffer_funcs for drivers that need |
138 | * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to | |
139 | * change &drm_framebuffer_funcs. The function does buffer size validation. | |
f2b816d7 AP |
140 | * The buffer size validation is for a general case, though, so users should |
141 | * pay attention to the checks being appropriate for them or, at least, | |
142 | * non-conflicting. | |
2e187b20 NT |
143 | * |
144 | * Returns: | |
f2b816d7 | 145 | * Zero or a negative error code. |
4c3dbb2c | 146 | */ |
f2b816d7 AP |
147 | int drm_gem_fb_init_with_funcs(struct drm_device *dev, |
148 | struct drm_framebuffer *fb, | |
149 | struct drm_file *file, | |
150 | const struct drm_mode_fb_cmd2 *mode_cmd, | |
151 | const struct drm_framebuffer_funcs *funcs) | |
4c3dbb2c NT |
152 | { |
153 | const struct drm_format_info *info; | |
154 | struct drm_gem_object *objs[4]; | |
4c3dbb2c NT |
155 | int ret, i; |
156 | ||
157 | info = drm_get_format_info(dev, mode_cmd); | |
158 | if (!info) | |
f2b816d7 | 159 | return -EINVAL; |
4c3dbb2c NT |
160 | |
161 | for (i = 0; i < info->num_planes; i++) { | |
162 | unsigned int width = mode_cmd->width / (i ? info->hsub : 1); | |
163 | unsigned int height = mode_cmd->height / (i ? info->vsub : 1); | |
164 | unsigned int min_size; | |
165 | ||
166 | objs[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]); | |
167 | if (!objs[i]) { | |
24f03be4 | 168 | drm_dbg_kms(dev, "Failed to lookup GEM object\n"); |
4c3dbb2c NT |
169 | ret = -ENOENT; |
170 | goto err_gem_object_put; | |
171 | } | |
172 | ||
173 | min_size = (height - 1) * mode_cmd->pitches[i] | |
042bf753 | 174 | + drm_format_info_min_pitch(info, i, width) |
4c3dbb2c NT |
175 | + mode_cmd->offsets[i]; |
176 | ||
177 | if (objs[i]->size < min_size) { | |
178 | drm_gem_object_put_unlocked(objs[i]); | |
179 | ret = -EINVAL; | |
180 | goto err_gem_object_put; | |
181 | } | |
182 | } | |
183 | ||
f2b816d7 AP |
184 | ret = drm_gem_fb_init(dev, fb, mode_cmd, objs, i, funcs); |
185 | if (ret) | |
4c3dbb2c | 186 | goto err_gem_object_put; |
4c3dbb2c | 187 | |
f2b816d7 | 188 | return 0; |
4c3dbb2c NT |
189 | |
190 | err_gem_object_put: | |
191 | for (i--; i >= 0; i--) | |
192 | drm_gem_object_put_unlocked(objs[i]); | |
193 | ||
f2b816d7 AP |
194 | return ret; |
195 | } | |
196 | EXPORT_SYMBOL_GPL(drm_gem_fb_init_with_funcs); | |
197 | ||
198 | /** | |
199 | * drm_gem_fb_create_with_funcs() - Helper function for the | |
200 | * &drm_mode_config_funcs.fb_create | |
201 | * callback | |
202 | * @dev: DRM device | |
203 | * @file: DRM file that holds the GEM handle(s) backing the framebuffer | |
204 | * @mode_cmd: Metadata from the userspace framebuffer creation request | |
205 | * @funcs: vtable to be used for the new framebuffer object | |
206 | * | |
207 | * This function can be used to set &drm_framebuffer_funcs for drivers that need | |
208 | * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to | |
209 | * change &drm_framebuffer_funcs. The function does buffer size validation. | |
210 | * | |
211 | * Returns: | |
212 | * Pointer to a &drm_framebuffer on success or an error pointer on failure. | |
213 | */ | |
214 | struct drm_framebuffer * | |
215 | drm_gem_fb_create_with_funcs(struct drm_device *dev, struct drm_file *file, | |
216 | const struct drm_mode_fb_cmd2 *mode_cmd, | |
217 | const struct drm_framebuffer_funcs *funcs) | |
218 | { | |
219 | struct drm_framebuffer *fb; | |
220 | int ret; | |
221 | ||
222 | fb = kzalloc(sizeof(*fb), GFP_KERNEL); | |
223 | if (!fb) | |
224 | return ERR_PTR(-ENOMEM); | |
225 | ||
226 | ret = drm_gem_fb_init_with_funcs(dev, fb, file, mode_cmd, funcs); | |
227 | if (ret) { | |
228 | kfree(fb); | |
229 | return ERR_PTR(ret); | |
230 | } | |
231 | ||
232 | return fb; | |
4c3dbb2c NT |
233 | } |
234 | EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_funcs); | |
235 | ||
236 | static const struct drm_framebuffer_funcs drm_gem_fb_funcs = { | |
237 | .destroy = drm_gem_fb_destroy, | |
238 | .create_handle = drm_gem_fb_create_handle, | |
239 | }; | |
240 | ||
241 | /** | |
2e187b20 NT |
242 | * drm_gem_fb_create() - Helper function for the |
243 | * &drm_mode_config_funcs.fb_create callback | |
4c3dbb2c | 244 | * @dev: DRM device |
2e187b20 NT |
245 | * @file: DRM file that holds the GEM handle(s) backing the framebuffer |
246 | * @mode_cmd: Metadata from the userspace framebuffer creation request | |
247 | * | |
248 | * This function creates a new framebuffer object described by | |
249 | * &drm_mode_fb_cmd2. This description includes handles for the buffer(s) | |
250 | * backing the framebuffer. | |
4c3dbb2c NT |
251 | * |
252 | * If your hardware has special alignment or pitch requirements these should be | |
253 | * checked before calling this function. The function does buffer size | |
dbd62e16 NT |
254 | * validation. Use drm_gem_fb_create_with_dirty() if you need framebuffer |
255 | * flushing. | |
2e187b20 NT |
256 | * |
257 | * Drivers can use this as their &drm_mode_config_funcs.fb_create callback. | |
258 | * The ADDFB2 IOCTL calls into this callback. | |
259 | * | |
260 | * Returns: | |
261 | * Pointer to a &drm_framebuffer on success or an error pointer on failure. | |
4c3dbb2c NT |
262 | */ |
263 | struct drm_framebuffer * | |
264 | drm_gem_fb_create(struct drm_device *dev, struct drm_file *file, | |
265 | const struct drm_mode_fb_cmd2 *mode_cmd) | |
266 | { | |
267 | return drm_gem_fb_create_with_funcs(dev, file, mode_cmd, | |
268 | &drm_gem_fb_funcs); | |
269 | } | |
270 | EXPORT_SYMBOL_GPL(drm_gem_fb_create); | |
271 | ||
dbd62e16 NT |
272 | static const struct drm_framebuffer_funcs drm_gem_fb_funcs_dirtyfb = { |
273 | .destroy = drm_gem_fb_destroy, | |
274 | .create_handle = drm_gem_fb_create_handle, | |
275 | .dirty = drm_atomic_helper_dirtyfb, | |
276 | }; | |
277 | ||
278 | /** | |
279 | * drm_gem_fb_create_with_dirty() - Helper function for the | |
280 | * &drm_mode_config_funcs.fb_create callback | |
281 | * @dev: DRM device | |
282 | * @file: DRM file that holds the GEM handle(s) backing the framebuffer | |
283 | * @mode_cmd: Metadata from the userspace framebuffer creation request | |
284 | * | |
285 | * This function creates a new framebuffer object described by | |
286 | * &drm_mode_fb_cmd2. This description includes handles for the buffer(s) | |
287 | * backing the framebuffer. drm_atomic_helper_dirtyfb() is used for the dirty | |
288 | * callback giving framebuffer flushing through the atomic machinery. Use | |
289 | * drm_gem_fb_create() if you don't need the dirty callback. | |
290 | * The function does buffer size validation. | |
291 | * | |
292 | * Drivers should also call drm_plane_enable_fb_damage_clips() on all planes | |
293 | * to enable userspace to use damage clips also with the ATOMIC IOCTL. | |
294 | * | |
295 | * Drivers can use this as their &drm_mode_config_funcs.fb_create callback. | |
296 | * The ADDFB2 IOCTL calls into this callback. | |
297 | * | |
298 | * Returns: | |
299 | * Pointer to a &drm_framebuffer on success or an error pointer on failure. | |
300 | */ | |
301 | struct drm_framebuffer * | |
302 | drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file, | |
303 | const struct drm_mode_fb_cmd2 *mode_cmd) | |
304 | { | |
305 | return drm_gem_fb_create_with_funcs(dev, file, mode_cmd, | |
306 | &drm_gem_fb_funcs_dirtyfb); | |
307 | } | |
308 | EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty); | |
309 | ||
bcf6293d AP |
310 | static __u32 drm_gem_afbc_get_bpp(struct drm_device *dev, |
311 | const struct drm_mode_fb_cmd2 *mode_cmd) | |
312 | { | |
313 | const struct drm_format_info *info; | |
314 | ||
315 | info = drm_get_format_info(dev, mode_cmd); | |
316 | ||
317 | /* use whatever a driver has set */ | |
318 | if (info->cpp[0]) | |
319 | return info->cpp[0] * 8; | |
320 | ||
321 | /* guess otherwise */ | |
322 | switch (info->format) { | |
323 | case DRM_FORMAT_YUV420_8BIT: | |
324 | return 12; | |
325 | case DRM_FORMAT_YUV420_10BIT: | |
326 | return 15; | |
327 | case DRM_FORMAT_VUY101010: | |
328 | return 30; | |
329 | default: | |
330 | break; | |
331 | } | |
332 | ||
333 | /* all attempts failed */ | |
334 | return 0; | |
335 | } | |
336 | ||
55f7f727 AP |
337 | static int drm_gem_afbc_min_size(struct drm_device *dev, |
338 | const struct drm_mode_fb_cmd2 *mode_cmd, | |
339 | struct drm_afbc_framebuffer *afbc_fb) | |
340 | { | |
55f7f727 AP |
341 | __u32 n_blocks, w_alignment, h_alignment, hdr_alignment; |
342 | /* remove bpp when all users properly encode cpp in drm_format_info */ | |
343 | __u32 bpp; | |
344 | ||
345 | switch (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK) { | |
346 | case AFBC_FORMAT_MOD_BLOCK_SIZE_16x16: | |
347 | afbc_fb->block_width = 16; | |
348 | afbc_fb->block_height = 16; | |
349 | break; | |
350 | case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8: | |
351 | afbc_fb->block_width = 32; | |
352 | afbc_fb->block_height = 8; | |
353 | break; | |
354 | /* no user exists yet - fall through */ | |
355 | case AFBC_FORMAT_MOD_BLOCK_SIZE_64x4: | |
356 | case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8_64x4: | |
357 | default: | |
88f1b29a AP |
358 | drm_dbg_kms(dev, "Invalid AFBC_FORMAT_MOD_BLOCK_SIZE: %lld.\n", |
359 | mode_cmd->modifier[0] | |
360 | & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK); | |
55f7f727 AP |
361 | return -EINVAL; |
362 | } | |
363 | ||
364 | /* tiled header afbc */ | |
365 | w_alignment = afbc_fb->block_width; | |
366 | h_alignment = afbc_fb->block_height; | |
367 | hdr_alignment = AFBC_HDR_ALIGN; | |
368 | if (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_TILED) { | |
369 | w_alignment *= AFBC_TH_LAYOUT_ALIGNMENT; | |
370 | h_alignment *= AFBC_TH_LAYOUT_ALIGNMENT; | |
371 | hdr_alignment = AFBC_TH_BODY_START_ALIGNMENT; | |
372 | } | |
373 | ||
374 | afbc_fb->aligned_width = ALIGN(mode_cmd->width, w_alignment); | |
375 | afbc_fb->aligned_height = ALIGN(mode_cmd->height, h_alignment); | |
376 | afbc_fb->offset = mode_cmd->offsets[0]; | |
377 | ||
bcf6293d AP |
378 | bpp = drm_gem_afbc_get_bpp(dev, mode_cmd); |
379 | if (!bpp) { | |
380 | drm_dbg_kms(dev, "Invalid AFBC bpp value: %d\n", bpp); | |
381 | return -EINVAL; | |
382 | } | |
55f7f727 AP |
383 | |
384 | n_blocks = (afbc_fb->aligned_width * afbc_fb->aligned_height) | |
385 | / AFBC_SUPERBLOCK_PIXELS; | |
386 | afbc_fb->afbc_size = ALIGN(n_blocks * AFBC_HEADER_SIZE, hdr_alignment); | |
387 | afbc_fb->afbc_size += n_blocks * ALIGN(bpp * AFBC_SUPERBLOCK_PIXELS / 8, | |
388 | AFBC_SUPERBLOCK_ALIGNMENT); | |
389 | ||
390 | return 0; | |
391 | } | |
392 | ||
393 | /** | |
394 | * drm_gem_fb_afbc_init() - Helper function for drivers using afbc to | |
395 | * fill and validate all the afbc-specific | |
396 | * struct drm_afbc_framebuffer members | |
397 | * | |
398 | * @dev: DRM device | |
399 | * @afbc_fb: afbc-specific framebuffer | |
400 | * @mode_cmd: Metadata from the userspace framebuffer creation request | |
401 | * @afbc_fb: afbc framebuffer | |
402 | * | |
403 | * This function can be used by drivers which support afbc to complete | |
404 | * the preparation of struct drm_afbc_framebuffer. It must be called after | |
405 | * allocating the said struct and calling drm_gem_fb_init_with_funcs(). | |
406 | * It is caller's responsibility to put afbc_fb->base.obj objects in case | |
407 | * the call is unsuccessful. | |
408 | * | |
409 | * Returns: | |
410 | * Zero on success or a negative error value on failure. | |
411 | */ | |
412 | int drm_gem_fb_afbc_init(struct drm_device *dev, | |
413 | const struct drm_mode_fb_cmd2 *mode_cmd, | |
414 | struct drm_afbc_framebuffer *afbc_fb) | |
415 | { | |
416 | const struct drm_format_info *info; | |
417 | struct drm_gem_object **objs; | |
418 | int ret; | |
419 | ||
420 | objs = afbc_fb->base.obj; | |
421 | info = drm_get_format_info(dev, mode_cmd); | |
422 | if (!info) | |
423 | return -EINVAL; | |
424 | ||
425 | ret = drm_gem_afbc_min_size(dev, mode_cmd, afbc_fb); | |
426 | if (ret < 0) | |
427 | return ret; | |
428 | ||
429 | if (objs[0]->size < afbc_fb->afbc_size) | |
430 | return -EINVAL; | |
431 | ||
432 | return 0; | |
433 | } | |
434 | EXPORT_SYMBOL_GPL(drm_gem_fb_afbc_init); | |
435 | ||
4c3dbb2c | 436 | /** |
2e187b20 NT |
437 | * drm_gem_fb_prepare_fb() - Prepare a GEM backed framebuffer |
438 | * @plane: Plane | |
439 | * @state: Plane state the fence will be attached to | |
4c3dbb2c | 440 | * |
bd630a86 DV |
441 | * This function extracts the exclusive fence from &drm_gem_object.resv and |
442 | * attaches it to plane state for the atomic helper to wait on. This is | |
443 | * necessary to correctly implement implicit synchronization for any buffers | |
444 | * shared as a struct &dma_buf. This function can be used as the | |
445 | * &drm_plane_helper_funcs.prepare_fb callback. | |
4c3dbb2c NT |
446 | * |
447 | * There is no need for &drm_plane_helper_funcs.cleanup_fb hook for simple | |
448 | * gem based framebuffer drivers which have their buffers always pinned in | |
449 | * memory. | |
1b94f477 DV |
450 | * |
451 | * See drm_atomic_set_fence_for_plane() for a discussion of implicit and | |
452 | * explicit fencing in atomic modeset updates. | |
4c3dbb2c NT |
453 | */ |
454 | int drm_gem_fb_prepare_fb(struct drm_plane *plane, | |
455 | struct drm_plane_state *state) | |
456 | { | |
bd630a86 | 457 | struct drm_gem_object *obj; |
4c3dbb2c NT |
458 | struct dma_fence *fence; |
459 | ||
9d54fcd5 | 460 | if (!state->fb) |
4c3dbb2c NT |
461 | return 0; |
462 | ||
bd630a86 | 463 | obj = drm_gem_fb_get_obj(state->fb, 0); |
52791eee | 464 | fence = dma_resv_get_excl_rcu(obj->resv); |
bd630a86 | 465 | drm_atomic_set_fence_for_plane(state, fence); |
4c3dbb2c NT |
466 | |
467 | return 0; | |
468 | } | |
469 | EXPORT_SYMBOL_GPL(drm_gem_fb_prepare_fb); | |
470 | ||
ccc3b2b3 DV |
471 | /** |
472 | * drm_gem_fb_simple_display_pipe_prepare_fb - prepare_fb helper for | |
473 | * &drm_simple_display_pipe | |
474 | * @pipe: Simple display pipe | |
475 | * @plane_state: Plane state | |
476 | * | |
bd630a86 DV |
477 | * This function uses drm_gem_fb_prepare_fb() to extract the exclusive fence |
478 | * from &drm_gem_object.resv and attaches it to plane state for the atomic | |
479 | * helper to wait on. This is necessary to correctly implement implicit | |
480 | * synchronization for any buffers shared as a struct &dma_buf. Drivers can use | |
481 | * this as their &drm_simple_display_pipe_funcs.prepare_fb callback. | |
1b94f477 DV |
482 | * |
483 | * See drm_atomic_set_fence_for_plane() for a discussion of implicit and | |
484 | * explicit fencing in atomic modeset updates. | |
ccc3b2b3 DV |
485 | */ |
486 | int drm_gem_fb_simple_display_pipe_prepare_fb(struct drm_simple_display_pipe *pipe, | |
487 | struct drm_plane_state *plane_state) | |
488 | { | |
489 | return drm_gem_fb_prepare_fb(&pipe->plane, plane_state); | |
490 | } | |
491 | EXPORT_SYMBOL(drm_gem_fb_simple_display_pipe_prepare_fb); |