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/slab.h> 9 #include <linux/module.h> 10 11 #include <drm/drm_damage_helper.h> 12 #include <drm/drm_drv.h> 13 #include <drm/drm_fourcc.h> 14 #include <drm/drm_framebuffer.h> 15 #include <drm/drm_gem.h> 16 #include <drm/drm_gem_framebuffer_helper.h> 17 #include <drm/drm_modeset_helper.h> 18 19 #include "drm_internal.h" 20 21 MODULE_IMPORT_NS("DMA_BUF"); 22 23 #define AFBC_HEADER_SIZE 16 24 #define AFBC_TH_LAYOUT_ALIGNMENT 8 25 #define AFBC_HDR_ALIGN 64 26 #define AFBC_SUPERBLOCK_PIXELS 256 27 #define AFBC_SUPERBLOCK_ALIGNMENT 128 28 #define AFBC_TH_BODY_START_ALIGNMENT 4096 29 30 /** 31 * DOC: overview 32 * 33 * This library provides helpers for drivers that don't subclass 34 * &drm_framebuffer and use &drm_gem_object for their backing storage. 35 * 36 * Drivers without additional needs to validate framebuffers can simply use 37 * drm_gem_fb_create() and everything is wired up automatically. Other drivers 38 * can use all parts independently. 39 */ 40 41 /** 42 * drm_gem_fb_get_obj() - Get GEM object backing the framebuffer 43 * @fb: Framebuffer 44 * @plane: Plane index 45 * 46 * No additional reference is taken beyond the one that the &drm_frambuffer 47 * already holds. 48 * 49 * Returns: 50 * Pointer to &drm_gem_object for the given framebuffer and plane index or NULL 51 * if it does not exist. 52 */ 53 struct drm_gem_object *drm_gem_fb_get_obj(struct drm_framebuffer *fb, 54 unsigned int plane) 55 { 56 struct drm_device *dev = fb->dev; 57 58 if (drm_WARN_ON_ONCE(dev, plane >= ARRAY_SIZE(fb->obj))) 59 return NULL; 60 else if (drm_WARN_ON_ONCE(dev, !fb->obj[plane])) 61 return NULL; 62 63 return fb->obj[plane]; 64 } 65 EXPORT_SYMBOL_GPL(drm_gem_fb_get_obj); 66 67 static int 68 drm_gem_fb_init(struct drm_device *dev, 69 struct drm_framebuffer *fb, 70 const struct drm_mode_fb_cmd2 *mode_cmd, 71 struct drm_gem_object **obj, unsigned int num_planes, 72 const struct drm_framebuffer_funcs *funcs) 73 { 74 unsigned int i; 75 int ret; 76 77 drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd); 78 79 for (i = 0; i < num_planes; i++) 80 fb->obj[i] = obj[i]; 81 82 ret = drm_framebuffer_init(dev, fb, funcs); 83 if (ret) 84 drm_err(dev, "Failed to init framebuffer: %d\n", ret); 85 86 return ret; 87 } 88 89 /** 90 * drm_gem_fb_destroy - Free GEM backed framebuffer 91 * @fb: Framebuffer 92 * 93 * Frees a GEM backed framebuffer with its backing buffer(s) and the structure 94 * itself. Drivers can use this as their &drm_framebuffer_funcs->destroy 95 * callback. 96 */ 97 void drm_gem_fb_destroy(struct drm_framebuffer *fb) 98 { 99 unsigned int i; 100 101 for (i = 0; i < fb->format->num_planes; i++) 102 drm_gem_object_handle_put_unlocked(fb->obj[i]); 103 104 drm_framebuffer_cleanup(fb); 105 kfree(fb); 106 } 107 EXPORT_SYMBOL(drm_gem_fb_destroy); 108 109 /** 110 * drm_gem_fb_create_handle - Create handle for GEM backed framebuffer 111 * @fb: Framebuffer 112 * @file: DRM file to register the handle for 113 * @handle: Pointer to return the created handle 114 * 115 * This function creates a handle for the GEM object backing the framebuffer. 116 * Drivers can use this as their &drm_framebuffer_funcs->create_handle 117 * callback. The GETFB IOCTL calls into this callback. 118 * 119 * Returns: 120 * 0 on success or a negative error code on failure. 121 */ 122 int drm_gem_fb_create_handle(struct drm_framebuffer *fb, struct drm_file *file, 123 unsigned int *handle) 124 { 125 return drm_gem_handle_create(file, fb->obj[0], handle); 126 } 127 EXPORT_SYMBOL(drm_gem_fb_create_handle); 128 129 /** 130 * drm_gem_fb_init_with_funcs() - Helper function for implementing 131 * &drm_mode_config_funcs.fb_create 132 * callback in cases when the driver 133 * allocates a subclass of 134 * struct drm_framebuffer 135 * @dev: DRM device 136 * @fb: framebuffer object 137 * @file: DRM file that holds the GEM handle(s) backing the framebuffer 138 * @mode_cmd: Metadata from the userspace framebuffer creation request 139 * @funcs: vtable to be used for the new framebuffer object 140 * 141 * This function can be used to set &drm_framebuffer_funcs for drivers that need 142 * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to 143 * change &drm_framebuffer_funcs. The function does buffer size validation. 144 * The buffer size validation is for a general case, though, so users should 145 * pay attention to the checks being appropriate for them or, at least, 146 * non-conflicting. 147 * 148 * Returns: 149 * Zero or a negative error code. 150 */ 151 int drm_gem_fb_init_with_funcs(struct drm_device *dev, 152 struct drm_framebuffer *fb, 153 struct drm_file *file, 154 const struct drm_mode_fb_cmd2 *mode_cmd, 155 const struct drm_framebuffer_funcs *funcs) 156 { 157 const struct drm_format_info *info; 158 struct drm_gem_object *objs[DRM_FORMAT_MAX_PLANES]; 159 unsigned int i; 160 int ret; 161 162 info = drm_get_format_info(dev, mode_cmd); 163 if (!info) { 164 drm_dbg_kms(dev, "Failed to get FB format info\n"); 165 return -EINVAL; 166 } 167 168 if (drm_drv_uses_atomic_modeset(dev) && 169 !drm_any_plane_has_format(dev, mode_cmd->pixel_format, 170 mode_cmd->modifier[0])) { 171 drm_dbg_kms(dev, "Unsupported pixel format %p4cc / modifier 0x%llx\n", 172 &mode_cmd->pixel_format, mode_cmd->modifier[0]); 173 return -EINVAL; 174 } 175 176 for (i = 0; i < info->num_planes; i++) { 177 unsigned int width = mode_cmd->width / (i ? info->hsub : 1); 178 unsigned int height = mode_cmd->height / (i ? info->vsub : 1); 179 unsigned int min_size; 180 181 objs[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]); 182 if (!objs[i]) { 183 drm_dbg_kms(dev, "Failed to lookup GEM object\n"); 184 ret = -ENOENT; 185 goto err_gem_object_handle_put_unlocked; 186 } 187 drm_gem_object_handle_get_unlocked(objs[i]); 188 drm_gem_object_put(objs[i]); 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_handle_put_unlocked(objs[i]); 199 ret = -EINVAL; 200 goto err_gem_object_handle_put_unlocked; 201 } 202 } 203 204 ret = drm_gem_fb_init(dev, fb, mode_cmd, objs, i, funcs); 205 if (ret) 206 goto err_gem_object_handle_put_unlocked; 207 208 return 0; 209 210 err_gem_object_handle_put_unlocked: 211 while (i > 0) { 212 --i; 213 drm_gem_object_handle_put_unlocked(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 * @mode_cmd: Metadata from the userspace framebuffer creation request 268 * 269 * This function creates a new framebuffer object described by 270 * &drm_mode_fb_cmd2. This description includes handles for the buffer(s) 271 * backing the framebuffer. 272 * 273 * If your hardware has special alignment or pitch requirements these should be 274 * checked before calling this function. The function does buffer size 275 * validation. Use drm_gem_fb_create_with_dirty() if you need framebuffer 276 * flushing. 277 * 278 * Drivers can use this as their &drm_mode_config_funcs.fb_create callback. 279 * The ADDFB2 IOCTL calls into this callback. 280 * 281 * Returns: 282 * Pointer to a &drm_framebuffer on success or an error pointer on failure. 283 */ 284 struct drm_framebuffer * 285 drm_gem_fb_create(struct drm_device *dev, struct drm_file *file, 286 const struct drm_mode_fb_cmd2 *mode_cmd) 287 { 288 return drm_gem_fb_create_with_funcs(dev, file, mode_cmd, 289 &drm_gem_fb_funcs); 290 } 291 EXPORT_SYMBOL_GPL(drm_gem_fb_create); 292 293 static const struct drm_framebuffer_funcs drm_gem_fb_funcs_dirtyfb = { 294 .destroy = drm_gem_fb_destroy, 295 .create_handle = drm_gem_fb_create_handle, 296 .dirty = drm_atomic_helper_dirtyfb, 297 }; 298 299 /** 300 * drm_gem_fb_create_with_dirty() - Helper function for the 301 * &drm_mode_config_funcs.fb_create callback 302 * @dev: DRM device 303 * @file: DRM file that holds the GEM handle(s) backing the framebuffer 304 * @mode_cmd: Metadata from the userspace framebuffer creation request 305 * 306 * This function creates a new framebuffer object described by 307 * &drm_mode_fb_cmd2. This description includes handles for the buffer(s) 308 * backing the framebuffer. drm_atomic_helper_dirtyfb() is used for the dirty 309 * callback giving framebuffer flushing through the atomic machinery. Use 310 * drm_gem_fb_create() if you don't need the dirty callback. 311 * The function does buffer size validation. 312 * 313 * Drivers should also call drm_plane_enable_fb_damage_clips() on all planes 314 * to enable userspace to use damage clips also with the ATOMIC IOCTL. 315 * 316 * Drivers can use this as their &drm_mode_config_funcs.fb_create callback. 317 * The ADDFB2 IOCTL calls into this callback. 318 * 319 * Returns: 320 * Pointer to a &drm_framebuffer on success or an error pointer on failure. 321 */ 322 struct drm_framebuffer * 323 drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file, 324 const struct drm_mode_fb_cmd2 *mode_cmd) 325 { 326 return drm_gem_fb_create_with_funcs(dev, file, mode_cmd, 327 &drm_gem_fb_funcs_dirtyfb); 328 } 329 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty); 330 331 /** 332 * drm_gem_fb_vmap - maps all framebuffer BOs into kernel address space 333 * @fb: the framebuffer 334 * @map: returns the mapping's address for each BO 335 * @data: returns the data address for each BO, can be NULL 336 * 337 * This function maps all buffer objects of the given framebuffer into 338 * kernel address space and stores them in struct iosys_map. If the 339 * mapping operation fails for one of the BOs, the function unmaps the 340 * already established mappings automatically. 341 * 342 * Callers that want to access a BO's stored data should pass @data. 343 * The argument returns the addresses of the data stored in each BO. This 344 * is different from @map if the framebuffer's offsets field is non-zero. 345 * 346 * Both, @map and @data, must each refer to arrays with at least 347 * fb->format->num_planes elements. 348 * 349 * See drm_gem_fb_vunmap() for unmapping. 350 * 351 * Returns: 352 * 0 on success, or a negative errno code otherwise. 353 */ 354 int drm_gem_fb_vmap(struct drm_framebuffer *fb, struct iosys_map *map, 355 struct iosys_map *data) 356 { 357 struct drm_gem_object *obj; 358 unsigned int i; 359 int ret; 360 361 for (i = 0; i < fb->format->num_planes; ++i) { 362 obj = drm_gem_fb_get_obj(fb, i); 363 if (!obj) { 364 ret = -EINVAL; 365 goto err_drm_gem_vunmap; 366 } 367 ret = drm_gem_vmap(obj, &map[i]); 368 if (ret) 369 goto err_drm_gem_vunmap; 370 } 371 372 if (data) { 373 for (i = 0; i < fb->format->num_planes; ++i) { 374 memcpy(&data[i], &map[i], sizeof(data[i])); 375 if (iosys_map_is_null(&data[i])) 376 continue; 377 iosys_map_incr(&data[i], fb->offsets[i]); 378 } 379 } 380 381 return 0; 382 383 err_drm_gem_vunmap: 384 while (i) { 385 --i; 386 obj = drm_gem_fb_get_obj(fb, i); 387 if (!obj) 388 continue; 389 drm_gem_vunmap(obj, &map[i]); 390 } 391 return ret; 392 } 393 EXPORT_SYMBOL(drm_gem_fb_vmap); 394 395 /** 396 * drm_gem_fb_vunmap - unmaps framebuffer BOs from kernel address space 397 * @fb: the framebuffer 398 * @map: mapping addresses as returned by drm_gem_fb_vmap() 399 * 400 * This function unmaps all buffer objects of the given framebuffer. 401 * 402 * See drm_gem_fb_vmap() for more information. 403 */ 404 void drm_gem_fb_vunmap(struct drm_framebuffer *fb, struct iosys_map *map) 405 { 406 unsigned int i = fb->format->num_planes; 407 struct drm_gem_object *obj; 408 409 while (i) { 410 --i; 411 obj = drm_gem_fb_get_obj(fb, i); 412 if (!obj) 413 continue; 414 if (iosys_map_is_null(&map[i])) 415 continue; 416 drm_gem_vunmap(obj, &map[i]); 417 } 418 } 419 EXPORT_SYMBOL(drm_gem_fb_vunmap); 420 421 static void __drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir, 422 unsigned int num_planes) 423 { 424 struct drm_gem_object *obj; 425 int ret; 426 427 while (num_planes) { 428 --num_planes; 429 obj = drm_gem_fb_get_obj(fb, num_planes); 430 if (!obj) 431 continue; 432 if (!drm_gem_is_imported(obj)) 433 continue; 434 ret = dma_buf_end_cpu_access(obj->dma_buf, dir); 435 if (ret) 436 drm_err(fb->dev, "dma_buf_end_cpu_access(%u, %d) failed: %d\n", 437 ret, num_planes, dir); 438 } 439 } 440 441 /** 442 * drm_gem_fb_begin_cpu_access - prepares GEM buffer objects for CPU access 443 * @fb: the framebuffer 444 * @dir: access mode 445 * 446 * Prepares a framebuffer's GEM buffer objects for CPU access. This function 447 * must be called before accessing the BO data within the kernel. For imported 448 * BOs, the function calls dma_buf_begin_cpu_access(). 449 * 450 * See drm_gem_fb_end_cpu_access() for signalling the end of CPU access. 451 * 452 * Returns: 453 * 0 on success, or a negative errno code otherwise. 454 */ 455 int drm_gem_fb_begin_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir) 456 { 457 struct drm_gem_object *obj; 458 unsigned int i; 459 int ret; 460 461 for (i = 0; i < fb->format->num_planes; ++i) { 462 obj = drm_gem_fb_get_obj(fb, i); 463 if (!obj) { 464 ret = -EINVAL; 465 goto err___drm_gem_fb_end_cpu_access; 466 } 467 if (!drm_gem_is_imported(obj)) 468 continue; 469 ret = dma_buf_begin_cpu_access(obj->dma_buf, dir); 470 if (ret) 471 goto err___drm_gem_fb_end_cpu_access; 472 } 473 474 return 0; 475 476 err___drm_gem_fb_end_cpu_access: 477 __drm_gem_fb_end_cpu_access(fb, dir, i); 478 return ret; 479 } 480 EXPORT_SYMBOL(drm_gem_fb_begin_cpu_access); 481 482 /** 483 * drm_gem_fb_end_cpu_access - signals end of CPU access to GEM buffer objects 484 * @fb: the framebuffer 485 * @dir: access mode 486 * 487 * Signals the end of CPU access to the given framebuffer's GEM buffer objects. This 488 * function must be paired with a corresponding call to drm_gem_fb_begin_cpu_access(). 489 * For imported BOs, the function calls dma_buf_end_cpu_access(). 490 * 491 * See also drm_gem_fb_begin_cpu_access(). 492 */ 493 void drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir) 494 { 495 __drm_gem_fb_end_cpu_access(fb, dir, fb->format->num_planes); 496 } 497 EXPORT_SYMBOL(drm_gem_fb_end_cpu_access); 498 499 // TODO Drop this function and replace by drm_format_info_bpp() once all 500 // DRM_FORMAT_* provide proper block info in drivers/gpu/drm/drm_fourcc.c 501 static __u32 drm_gem_afbc_get_bpp(struct drm_device *dev, 502 const struct drm_mode_fb_cmd2 *mode_cmd) 503 { 504 const struct drm_format_info *info; 505 506 info = drm_get_format_info(dev, mode_cmd); 507 508 switch (info->format) { 509 case DRM_FORMAT_YUV420_8BIT: 510 return 12; 511 case DRM_FORMAT_YUV420_10BIT: 512 return 15; 513 case DRM_FORMAT_VUY101010: 514 return 30; 515 default: 516 return drm_format_info_bpp(info, 0); 517 } 518 } 519 520 static int drm_gem_afbc_min_size(struct drm_device *dev, 521 const struct drm_mode_fb_cmd2 *mode_cmd, 522 struct drm_afbc_framebuffer *afbc_fb) 523 { 524 __u32 n_blocks, w_alignment, h_alignment, hdr_alignment; 525 /* remove bpp when all users properly encode cpp in drm_format_info */ 526 __u32 bpp; 527 528 switch (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK) { 529 case AFBC_FORMAT_MOD_BLOCK_SIZE_16x16: 530 afbc_fb->block_width = 16; 531 afbc_fb->block_height = 16; 532 break; 533 case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8: 534 afbc_fb->block_width = 32; 535 afbc_fb->block_height = 8; 536 break; 537 /* no user exists yet - fall through */ 538 case AFBC_FORMAT_MOD_BLOCK_SIZE_64x4: 539 case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8_64x4: 540 default: 541 drm_dbg_kms(dev, "Invalid AFBC_FORMAT_MOD_BLOCK_SIZE: %lld.\n", 542 mode_cmd->modifier[0] 543 & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK); 544 return -EINVAL; 545 } 546 547 /* tiled header afbc */ 548 w_alignment = afbc_fb->block_width; 549 h_alignment = afbc_fb->block_height; 550 hdr_alignment = AFBC_HDR_ALIGN; 551 if (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_TILED) { 552 w_alignment *= AFBC_TH_LAYOUT_ALIGNMENT; 553 h_alignment *= AFBC_TH_LAYOUT_ALIGNMENT; 554 hdr_alignment = AFBC_TH_BODY_START_ALIGNMENT; 555 } 556 557 afbc_fb->aligned_width = ALIGN(mode_cmd->width, w_alignment); 558 afbc_fb->aligned_height = ALIGN(mode_cmd->height, h_alignment); 559 afbc_fb->offset = mode_cmd->offsets[0]; 560 561 bpp = drm_gem_afbc_get_bpp(dev, mode_cmd); 562 if (!bpp) { 563 drm_dbg_kms(dev, "Invalid AFBC bpp value: %d\n", bpp); 564 return -EINVAL; 565 } 566 567 n_blocks = (afbc_fb->aligned_width * afbc_fb->aligned_height) 568 / AFBC_SUPERBLOCK_PIXELS; 569 afbc_fb->afbc_size = ALIGN(n_blocks * AFBC_HEADER_SIZE, hdr_alignment); 570 afbc_fb->afbc_size += n_blocks * ALIGN(bpp * AFBC_SUPERBLOCK_PIXELS / 8, 571 AFBC_SUPERBLOCK_ALIGNMENT); 572 573 return 0; 574 } 575 576 /** 577 * drm_gem_fb_afbc_init() - Helper function for drivers using afbc to 578 * fill and validate all the afbc-specific 579 * struct drm_afbc_framebuffer members 580 * 581 * @dev: DRM device 582 * @afbc_fb: afbc-specific framebuffer 583 * @mode_cmd: Metadata from the userspace framebuffer creation request 584 * @afbc_fb: afbc framebuffer 585 * 586 * This function can be used by drivers which support afbc to complete 587 * the preparation of struct drm_afbc_framebuffer. It must be called after 588 * allocating the said struct and calling drm_gem_fb_init_with_funcs(). 589 * It is caller's responsibility to put afbc_fb->base.obj objects in case 590 * the call is unsuccessful. 591 * 592 * Returns: 593 * Zero on success or a negative error value on failure. 594 */ 595 int drm_gem_fb_afbc_init(struct drm_device *dev, 596 const struct drm_mode_fb_cmd2 *mode_cmd, 597 struct drm_afbc_framebuffer *afbc_fb) 598 { 599 const struct drm_format_info *info; 600 struct drm_gem_object **objs; 601 int ret; 602 603 objs = afbc_fb->base.obj; 604 info = drm_get_format_info(dev, mode_cmd); 605 if (!info) 606 return -EINVAL; 607 608 ret = drm_gem_afbc_min_size(dev, mode_cmd, afbc_fb); 609 if (ret < 0) 610 return ret; 611 612 if (objs[0]->size < afbc_fb->afbc_size) 613 return -EINVAL; 614 615 return 0; 616 } 617 EXPORT_SYMBOL_GPL(drm_gem_fb_afbc_init); 618