1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * drm gem framebuffer helper functions 4 * 5 * Copyright (C) 2017 Noralf Trønnes 6 */ 7 8 #include <linux/export.h> 9 #include <linux/slab.h> 10 #include <linux/module.h> 11 12 #include <drm/drm_damage_helper.h> 13 #include <drm/drm_drv.h> 14 #include <drm/drm_fourcc.h> 15 #include <drm/drm_framebuffer.h> 16 #include <drm/drm_gem.h> 17 #include <drm/drm_gem_framebuffer_helper.h> 18 #include <drm/drm_modeset_helper.h> 19 20 #include "drm_internal.h" 21 22 MODULE_IMPORT_NS("DMA_BUF"); 23 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 31 /** 32 * DOC: overview 33 * 34 * This library provides helpers for drivers that don't subclass 35 * &drm_framebuffer and use &drm_gem_object for their backing storage. 36 * 37 * Drivers without additional needs to validate framebuffers can simply use 38 * drm_gem_fb_create() and everything is wired up automatically. Other drivers 39 * can use all parts independently. 40 */ 41 42 /** 43 * drm_gem_fb_get_obj() - Get GEM object backing the framebuffer 44 * @fb: Framebuffer 45 * @plane: Plane index 46 * 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. 53 */ 54 struct drm_gem_object *drm_gem_fb_get_obj(struct drm_framebuffer *fb, 55 unsigned int plane) 56 { 57 struct drm_device *dev = fb->dev; 58 59 if (drm_WARN_ON_ONCE(dev, plane >= ARRAY_SIZE(fb->obj))) 60 return NULL; 61 else if (drm_WARN_ON_ONCE(dev, !fb->obj[plane])) 62 return NULL; 63 64 return fb->obj[plane]; 65 } 66 EXPORT_SYMBOL_GPL(drm_gem_fb_get_obj); 67 68 static int 69 drm_gem_fb_init(struct drm_device *dev, 70 struct drm_framebuffer *fb, 71 const struct drm_mode_fb_cmd2 *mode_cmd, 72 struct drm_gem_object **obj, unsigned int num_planes, 73 const struct drm_framebuffer_funcs *funcs) 74 { 75 unsigned int i; 76 int ret; 77 78 drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd); 79 80 for (i = 0; i < num_planes; i++) 81 fb->obj[i] = obj[i]; 82 83 ret = drm_framebuffer_init(dev, fb, funcs); 84 if (ret) 85 drm_err(dev, "Failed to init framebuffer: %d\n", ret); 86 87 return ret; 88 } 89 90 /** 91 * drm_gem_fb_destroy - Free GEM backed framebuffer 92 * @fb: Framebuffer 93 * 94 * Frees a GEM backed framebuffer with its backing buffer(s) and the structure 95 * itself. Drivers can use this as their &drm_framebuffer_funcs->destroy 96 * callback. 97 */ 98 void drm_gem_fb_destroy(struct drm_framebuffer *fb) 99 { 100 unsigned int i; 101 102 for (i = 0; i < fb->format->num_planes; i++) 103 drm_gem_object_put(fb->obj[i]); 104 105 drm_framebuffer_cleanup(fb); 106 kfree(fb); 107 } 108 EXPORT_SYMBOL(drm_gem_fb_destroy); 109 110 /** 111 * drm_gem_fb_create_handle - Create handle for GEM backed framebuffer 112 * @fb: Framebuffer 113 * @file: DRM file to register the handle for 114 * @handle: Pointer to return the created handle 115 * 116 * This function creates a handle for the GEM object backing the framebuffer. 117 * Drivers can use this as their &drm_framebuffer_funcs->create_handle 118 * callback. The GETFB IOCTL calls into this callback. 119 * 120 * Returns: 121 * 0 on success or a negative error code on failure. 122 */ 123 int drm_gem_fb_create_handle(struct drm_framebuffer *fb, struct drm_file *file, 124 unsigned int *handle) 125 { 126 return drm_gem_handle_create(file, fb->obj[0], handle); 127 } 128 EXPORT_SYMBOL(drm_gem_fb_create_handle); 129 130 /** 131 * drm_gem_fb_init_with_funcs() - Helper function for implementing 132 * &drm_mode_config_funcs.fb_create 133 * callback in cases when the driver 134 * allocates a subclass of 135 * struct drm_framebuffer 136 * @dev: DRM device 137 * @fb: framebuffer object 138 * @file: DRM file that holds the GEM handle(s) backing the framebuffer 139 * @mode_cmd: Metadata from the userspace framebuffer creation request 140 * @funcs: vtable to be used for the new framebuffer object 141 * 142 * This function can be used to set &drm_framebuffer_funcs for drivers that need 143 * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to 144 * change &drm_framebuffer_funcs. The function does buffer size validation. 145 * The buffer size validation is for a general case, though, so users should 146 * pay attention to the checks being appropriate for them or, at least, 147 * non-conflicting. 148 * 149 * Returns: 150 * Zero or a negative error code. 151 */ 152 int drm_gem_fb_init_with_funcs(struct drm_device *dev, 153 struct drm_framebuffer *fb, 154 struct drm_file *file, 155 const struct drm_mode_fb_cmd2 *mode_cmd, 156 const struct drm_framebuffer_funcs *funcs) 157 { 158 const struct drm_format_info *info; 159 struct drm_gem_object *objs[DRM_FORMAT_MAX_PLANES]; 160 unsigned int i; 161 int ret; 162 163 info = drm_get_format_info(dev, mode_cmd->pixel_format, 164 mode_cmd->modifier[0]); 165 if (!info) { 166 drm_dbg_kms(dev, "Failed to get FB format info\n"); 167 return -EINVAL; 168 } 169 170 if (drm_drv_uses_atomic_modeset(dev) && 171 !drm_any_plane_has_format(dev, mode_cmd->pixel_format, 172 mode_cmd->modifier[0])) { 173 drm_dbg_kms(dev, "Unsupported pixel format %p4cc / modifier 0x%llx\n", 174 &mode_cmd->pixel_format, mode_cmd->modifier[0]); 175 return -EINVAL; 176 } 177 178 for (i = 0; i < info->num_planes; i++) { 179 unsigned int width = mode_cmd->width / (i ? info->hsub : 1); 180 unsigned int height = mode_cmd->height / (i ? info->vsub : 1); 181 unsigned int min_size; 182 183 objs[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]); 184 if (!objs[i]) { 185 drm_dbg_kms(dev, "Failed to lookup GEM object\n"); 186 ret = -ENOENT; 187 goto err_gem_object_put; 188 } 189 190 min_size = (height - 1) * mode_cmd->pitches[i] 191 + drm_format_info_min_pitch(info, i, width) 192 + mode_cmd->offsets[i]; 193 194 if (objs[i]->size < min_size) { 195 drm_dbg_kms(dev, 196 "GEM object size (%zu) smaller than minimum size (%u) for plane %d\n", 197 objs[i]->size, min_size, i); 198 drm_gem_object_put(objs[i]); 199 ret = -EINVAL; 200 goto err_gem_object_put; 201 } 202 } 203 204 ret = drm_gem_fb_init(dev, fb, mode_cmd, objs, i, funcs); 205 if (ret) 206 goto err_gem_object_put; 207 208 return 0; 209 210 err_gem_object_put: 211 while (i > 0) { 212 --i; 213 drm_gem_object_put(objs[i]); 214 } 215 return ret; 216 } 217 EXPORT_SYMBOL_GPL(drm_gem_fb_init_with_funcs); 218 219 /** 220 * drm_gem_fb_create_with_funcs() - Helper function for the 221 * &drm_mode_config_funcs.fb_create 222 * callback 223 * @dev: DRM device 224 * @file: DRM file that holds the GEM handle(s) backing the framebuffer 225 * @mode_cmd: Metadata from the userspace framebuffer creation request 226 * @funcs: vtable to be used for the new framebuffer object 227 * 228 * This function can be used to set &drm_framebuffer_funcs for drivers that need 229 * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to 230 * change &drm_framebuffer_funcs. The function does buffer size validation. 231 * 232 * Returns: 233 * Pointer to a &drm_framebuffer on success or an error pointer on failure. 234 */ 235 struct drm_framebuffer * 236 drm_gem_fb_create_with_funcs(struct drm_device *dev, struct drm_file *file, 237 const struct drm_mode_fb_cmd2 *mode_cmd, 238 const struct drm_framebuffer_funcs *funcs) 239 { 240 struct drm_framebuffer *fb; 241 int ret; 242 243 fb = kzalloc(sizeof(*fb), GFP_KERNEL); 244 if (!fb) 245 return ERR_PTR(-ENOMEM); 246 247 ret = drm_gem_fb_init_with_funcs(dev, fb, file, mode_cmd, funcs); 248 if (ret) { 249 kfree(fb); 250 return ERR_PTR(ret); 251 } 252 253 return fb; 254 } 255 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_funcs); 256 257 static const struct drm_framebuffer_funcs drm_gem_fb_funcs = { 258 .destroy = drm_gem_fb_destroy, 259 .create_handle = drm_gem_fb_create_handle, 260 }; 261 262 /** 263 * drm_gem_fb_create() - Helper function for the 264 * &drm_mode_config_funcs.fb_create callback 265 * @dev: DRM device 266 * @file: DRM file that holds the GEM handle(s) backing the framebuffer 267 * @info: pixel format information 268 * @mode_cmd: Metadata from the userspace framebuffer creation request 269 * 270 * This function creates a new framebuffer object described by 271 * &drm_mode_fb_cmd2. This description includes handles for the buffer(s) 272 * backing the framebuffer. 273 * 274 * If your hardware has special alignment or pitch requirements these should be 275 * checked before calling this function. The function does buffer size 276 * validation. Use drm_gem_fb_create_with_dirty() if you need framebuffer 277 * flushing. 278 * 279 * Drivers can use this as their &drm_mode_config_funcs.fb_create callback. 280 * The ADDFB2 IOCTL calls into this callback. 281 * 282 * Returns: 283 * Pointer to a &drm_framebuffer on success or an error pointer on failure. 284 */ 285 struct drm_framebuffer * 286 drm_gem_fb_create(struct drm_device *dev, struct drm_file *file, 287 const struct drm_format_info *info, 288 const struct drm_mode_fb_cmd2 *mode_cmd) 289 { 290 return drm_gem_fb_create_with_funcs(dev, file, mode_cmd, 291 &drm_gem_fb_funcs); 292 } 293 EXPORT_SYMBOL_GPL(drm_gem_fb_create); 294 295 static const struct drm_framebuffer_funcs drm_gem_fb_funcs_dirtyfb = { 296 .destroy = drm_gem_fb_destroy, 297 .create_handle = drm_gem_fb_create_handle, 298 .dirty = drm_atomic_helper_dirtyfb, 299 }; 300 301 /** 302 * drm_gem_fb_create_with_dirty() - Helper function for the 303 * &drm_mode_config_funcs.fb_create callback 304 * @dev: DRM device 305 * @file: DRM file that holds the GEM handle(s) backing the framebuffer 306 * @info: pixel format information 307 * @mode_cmd: Metadata from the userspace framebuffer creation request 308 * 309 * This function creates a new framebuffer object described by 310 * &drm_mode_fb_cmd2. This description includes handles for the buffer(s) 311 * backing the framebuffer. drm_atomic_helper_dirtyfb() is used for the dirty 312 * callback giving framebuffer flushing through the atomic machinery. Use 313 * drm_gem_fb_create() if you don't need the dirty callback. 314 * The function does buffer size validation. 315 * 316 * Drivers should also call drm_plane_enable_fb_damage_clips() on all planes 317 * to enable userspace to use damage clips also with the ATOMIC IOCTL. 318 * 319 * Drivers can use this as their &drm_mode_config_funcs.fb_create callback. 320 * The ADDFB2 IOCTL calls into this callback. 321 * 322 * Returns: 323 * Pointer to a &drm_framebuffer on success or an error pointer on failure. 324 */ 325 struct drm_framebuffer * 326 drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file, 327 const struct drm_format_info *info, 328 const struct drm_mode_fb_cmd2 *mode_cmd) 329 { 330 return drm_gem_fb_create_with_funcs(dev, file, mode_cmd, 331 &drm_gem_fb_funcs_dirtyfb); 332 } 333 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty); 334 335 /** 336 * drm_gem_fb_vmap - maps all framebuffer BOs into kernel address space 337 * @fb: the framebuffer 338 * @map: returns the mapping's address for each BO 339 * @data: returns the data address for each BO, can be NULL 340 * 341 * This function maps all buffer objects of the given framebuffer into 342 * kernel address space and stores them in struct iosys_map. If the 343 * mapping operation fails for one of the BOs, the function unmaps the 344 * already established mappings automatically. 345 * 346 * Callers that want to access a BO's stored data should pass @data. 347 * The argument returns the addresses of the data stored in each BO. This 348 * is different from @map if the framebuffer's offsets field is non-zero. 349 * 350 * Both, @map and @data, must each refer to arrays with at least 351 * fb->format->num_planes elements. 352 * 353 * See drm_gem_fb_vunmap() for unmapping. 354 * 355 * Returns: 356 * 0 on success, or a negative errno code otherwise. 357 */ 358 int drm_gem_fb_vmap(struct drm_framebuffer *fb, struct iosys_map *map, 359 struct iosys_map *data) 360 { 361 struct drm_gem_object *obj; 362 unsigned int i; 363 int ret; 364 365 for (i = 0; i < fb->format->num_planes; ++i) { 366 obj = drm_gem_fb_get_obj(fb, i); 367 if (!obj) { 368 ret = -EINVAL; 369 goto err_drm_gem_vunmap; 370 } 371 ret = drm_gem_vmap(obj, &map[i]); 372 if (ret) 373 goto err_drm_gem_vunmap; 374 } 375 376 if (data) { 377 for (i = 0; i < fb->format->num_planes; ++i) { 378 memcpy(&data[i], &map[i], sizeof(data[i])); 379 if (iosys_map_is_null(&data[i])) 380 continue; 381 iosys_map_incr(&data[i], fb->offsets[i]); 382 } 383 } 384 385 return 0; 386 387 err_drm_gem_vunmap: 388 while (i) { 389 --i; 390 obj = drm_gem_fb_get_obj(fb, i); 391 if (!obj) 392 continue; 393 drm_gem_vunmap(obj, &map[i]); 394 } 395 return ret; 396 } 397 EXPORT_SYMBOL(drm_gem_fb_vmap); 398 399 /** 400 * drm_gem_fb_vunmap - unmaps framebuffer BOs from kernel address space 401 * @fb: the framebuffer 402 * @map: mapping addresses as returned by drm_gem_fb_vmap() 403 * 404 * This function unmaps all buffer objects of the given framebuffer. 405 * 406 * See drm_gem_fb_vmap() for more information. 407 */ 408 void drm_gem_fb_vunmap(struct drm_framebuffer *fb, struct iosys_map *map) 409 { 410 unsigned int i = fb->format->num_planes; 411 struct drm_gem_object *obj; 412 413 while (i) { 414 --i; 415 obj = drm_gem_fb_get_obj(fb, i); 416 if (!obj) 417 continue; 418 if (iosys_map_is_null(&map[i])) 419 continue; 420 drm_gem_vunmap(obj, &map[i]); 421 } 422 } 423 EXPORT_SYMBOL(drm_gem_fb_vunmap); 424 425 static void __drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir, 426 unsigned int num_planes) 427 { 428 struct drm_gem_object *obj; 429 int ret; 430 431 while (num_planes) { 432 --num_planes; 433 obj = drm_gem_fb_get_obj(fb, num_planes); 434 if (!obj) 435 continue; 436 if (!drm_gem_is_imported(obj)) 437 continue; 438 ret = dma_buf_end_cpu_access(obj->dma_buf, dir); 439 if (ret) 440 drm_err(fb->dev, "dma_buf_end_cpu_access(%u, %d) failed: %d\n", 441 ret, num_planes, dir); 442 } 443 } 444 445 /** 446 * drm_gem_fb_begin_cpu_access - prepares GEM buffer objects for CPU access 447 * @fb: the framebuffer 448 * @dir: access mode 449 * 450 * Prepares a framebuffer's GEM buffer objects for CPU access. This function 451 * must be called before accessing the BO data within the kernel. For imported 452 * BOs, the function calls dma_buf_begin_cpu_access(). 453 * 454 * See drm_gem_fb_end_cpu_access() for signalling the end of CPU access. 455 * 456 * Returns: 457 * 0 on success, or a negative errno code otherwise. 458 */ 459 int drm_gem_fb_begin_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir) 460 { 461 struct drm_gem_object *obj; 462 unsigned int i; 463 int ret; 464 465 for (i = 0; i < fb->format->num_planes; ++i) { 466 obj = drm_gem_fb_get_obj(fb, i); 467 if (!obj) { 468 ret = -EINVAL; 469 goto err___drm_gem_fb_end_cpu_access; 470 } 471 if (!drm_gem_is_imported(obj)) 472 continue; 473 ret = dma_buf_begin_cpu_access(obj->dma_buf, dir); 474 if (ret) 475 goto err___drm_gem_fb_end_cpu_access; 476 } 477 478 return 0; 479 480 err___drm_gem_fb_end_cpu_access: 481 __drm_gem_fb_end_cpu_access(fb, dir, i); 482 return ret; 483 } 484 EXPORT_SYMBOL(drm_gem_fb_begin_cpu_access); 485 486 /** 487 * drm_gem_fb_end_cpu_access - signals end of CPU access to GEM buffer objects 488 * @fb: the framebuffer 489 * @dir: access mode 490 * 491 * Signals the end of CPU access to the given framebuffer's GEM buffer objects. This 492 * function must be paired with a corresponding call to drm_gem_fb_begin_cpu_access(). 493 * For imported BOs, the function calls dma_buf_end_cpu_access(). 494 * 495 * See also drm_gem_fb_begin_cpu_access(). 496 */ 497 void drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir) 498 { 499 __drm_gem_fb_end_cpu_access(fb, dir, fb->format->num_planes); 500 } 501 EXPORT_SYMBOL(drm_gem_fb_end_cpu_access); 502 503 // TODO Drop this function and replace by drm_format_info_bpp() once all 504 // DRM_FORMAT_* provide proper block info in drivers/gpu/drm/drm_fourcc.c 505 static __u32 drm_gem_afbc_get_bpp(struct drm_device *dev, 506 const struct drm_mode_fb_cmd2 *mode_cmd) 507 { 508 const struct drm_format_info *info; 509 510 info = drm_get_format_info(dev, mode_cmd->pixel_format, 511 mode_cmd->modifier[0]); 512 513 switch (info->format) { 514 case DRM_FORMAT_YUV420_8BIT: 515 return 12; 516 case DRM_FORMAT_YUV420_10BIT: 517 return 15; 518 case DRM_FORMAT_VUY101010: 519 return 30; 520 default: 521 return drm_format_info_bpp(info, 0); 522 } 523 } 524 525 static int drm_gem_afbc_min_size(struct drm_device *dev, 526 const struct drm_mode_fb_cmd2 *mode_cmd, 527 struct drm_afbc_framebuffer *afbc_fb) 528 { 529 __u32 n_blocks, w_alignment, h_alignment, hdr_alignment; 530 /* remove bpp when all users properly encode cpp in drm_format_info */ 531 __u32 bpp; 532 533 switch (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK) { 534 case AFBC_FORMAT_MOD_BLOCK_SIZE_16x16: 535 afbc_fb->block_width = 16; 536 afbc_fb->block_height = 16; 537 break; 538 case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8: 539 afbc_fb->block_width = 32; 540 afbc_fb->block_height = 8; 541 break; 542 /* no user exists yet - fall through */ 543 case AFBC_FORMAT_MOD_BLOCK_SIZE_64x4: 544 case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8_64x4: 545 default: 546 drm_dbg_kms(dev, "Invalid AFBC_FORMAT_MOD_BLOCK_SIZE: %lld.\n", 547 mode_cmd->modifier[0] 548 & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK); 549 return -EINVAL; 550 } 551 552 /* tiled header afbc */ 553 w_alignment = afbc_fb->block_width; 554 h_alignment = afbc_fb->block_height; 555 hdr_alignment = AFBC_HDR_ALIGN; 556 if (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_TILED) { 557 w_alignment *= AFBC_TH_LAYOUT_ALIGNMENT; 558 h_alignment *= AFBC_TH_LAYOUT_ALIGNMENT; 559 hdr_alignment = AFBC_TH_BODY_START_ALIGNMENT; 560 } 561 562 afbc_fb->aligned_width = ALIGN(mode_cmd->width, w_alignment); 563 afbc_fb->aligned_height = ALIGN(mode_cmd->height, h_alignment); 564 afbc_fb->offset = mode_cmd->offsets[0]; 565 566 bpp = drm_gem_afbc_get_bpp(dev, mode_cmd); 567 if (!bpp) { 568 drm_dbg_kms(dev, "Invalid AFBC bpp value: %d\n", bpp); 569 return -EINVAL; 570 } 571 572 n_blocks = (afbc_fb->aligned_width * afbc_fb->aligned_height) 573 / AFBC_SUPERBLOCK_PIXELS; 574 afbc_fb->afbc_size = ALIGN(n_blocks * AFBC_HEADER_SIZE, hdr_alignment); 575 afbc_fb->afbc_size += n_blocks * ALIGN(bpp * AFBC_SUPERBLOCK_PIXELS / 8, 576 AFBC_SUPERBLOCK_ALIGNMENT); 577 578 return 0; 579 } 580 581 /** 582 * drm_gem_fb_afbc_init() - Helper function for drivers using afbc to 583 * fill and validate all the afbc-specific 584 * struct drm_afbc_framebuffer members 585 * 586 * @dev: DRM device 587 * @afbc_fb: afbc-specific framebuffer 588 * @mode_cmd: Metadata from the userspace framebuffer creation request 589 * @afbc_fb: afbc framebuffer 590 * 591 * This function can be used by drivers which support afbc to complete 592 * the preparation of struct drm_afbc_framebuffer. It must be called after 593 * allocating the said struct and calling drm_gem_fb_init_with_funcs(). 594 * It is caller's responsibility to put afbc_fb->base.obj objects in case 595 * the call is unsuccessful. 596 * 597 * Returns: 598 * Zero on success or a negative error value on failure. 599 */ 600 int drm_gem_fb_afbc_init(struct drm_device *dev, 601 const struct drm_mode_fb_cmd2 *mode_cmd, 602 struct drm_afbc_framebuffer *afbc_fb) 603 { 604 const struct drm_format_info *info; 605 struct drm_gem_object **objs; 606 int ret; 607 608 objs = afbc_fb->base.obj; 609 info = drm_get_format_info(dev, mode_cmd->pixel_format, 610 mode_cmd->modifier[0]); 611 if (!info) 612 return -EINVAL; 613 614 ret = drm_gem_afbc_min_size(dev, mode_cmd, afbc_fb); 615 if (ret < 0) 616 return ret; 617 618 if (objs[0]->size < afbc_fb->afbc_size) { 619 drm_dbg_kms(dev, "GEM object size (%zu) smaller than minimum afbc size (%u)\n", 620 objs[0]->size, afbc_fb->afbc_size); 621 return -EINVAL; 622 } 623 624 return 0; 625 } 626 EXPORT_SYMBOL_GPL(drm_gem_fb_afbc_init); 627