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_put(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_put; 186 } 187 188 min_size = (height - 1) * mode_cmd->pitches[i] 189 + drm_format_info_min_pitch(info, i, width) 190 + mode_cmd->offsets[i]; 191 192 if (objs[i]->size < min_size) { 193 drm_dbg_kms(dev, 194 "GEM object size (%zu) smaller than minimum size (%u) for plane %d\n", 195 objs[i]->size, min_size, i); 196 drm_gem_object_put(objs[i]); 197 ret = -EINVAL; 198 goto err_gem_object_put; 199 } 200 } 201 202 ret = drm_gem_fb_init(dev, fb, mode_cmd, objs, i, funcs); 203 if (ret) 204 goto err_gem_object_put; 205 206 return 0; 207 208 err_gem_object_put: 209 while (i > 0) { 210 --i; 211 drm_gem_object_put(objs[i]); 212 } 213 return ret; 214 } 215 EXPORT_SYMBOL_GPL(drm_gem_fb_init_with_funcs); 216 217 /** 218 * drm_gem_fb_create_with_funcs() - Helper function for the 219 * &drm_mode_config_funcs.fb_create 220 * callback 221 * @dev: DRM device 222 * @file: DRM file that holds the GEM handle(s) backing the framebuffer 223 * @mode_cmd: Metadata from the userspace framebuffer creation request 224 * @funcs: vtable to be used for the new framebuffer object 225 * 226 * This function can be used to set &drm_framebuffer_funcs for drivers that need 227 * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to 228 * change &drm_framebuffer_funcs. The function does buffer size validation. 229 * 230 * Returns: 231 * Pointer to a &drm_framebuffer on success or an error pointer on failure. 232 */ 233 struct drm_framebuffer * 234 drm_gem_fb_create_with_funcs(struct drm_device *dev, struct drm_file *file, 235 const struct drm_mode_fb_cmd2 *mode_cmd, 236 const struct drm_framebuffer_funcs *funcs) 237 { 238 struct drm_framebuffer *fb; 239 int ret; 240 241 fb = kzalloc(sizeof(*fb), GFP_KERNEL); 242 if (!fb) 243 return ERR_PTR(-ENOMEM); 244 245 ret = drm_gem_fb_init_with_funcs(dev, fb, file, mode_cmd, funcs); 246 if (ret) { 247 kfree(fb); 248 return ERR_PTR(ret); 249 } 250 251 return fb; 252 } 253 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_funcs); 254 255 static const struct drm_framebuffer_funcs drm_gem_fb_funcs = { 256 .destroy = drm_gem_fb_destroy, 257 .create_handle = drm_gem_fb_create_handle, 258 }; 259 260 /** 261 * drm_gem_fb_create() - Helper function for the 262 * &drm_mode_config_funcs.fb_create callback 263 * @dev: DRM device 264 * @file: DRM file that holds the GEM handle(s) backing the framebuffer 265 * @mode_cmd: Metadata from the userspace framebuffer creation request 266 * 267 * This function creates a new framebuffer object described by 268 * &drm_mode_fb_cmd2. This description includes handles for the buffer(s) 269 * backing the framebuffer. 270 * 271 * If your hardware has special alignment or pitch requirements these should be 272 * checked before calling this function. The function does buffer size 273 * validation. Use drm_gem_fb_create_with_dirty() if you need framebuffer 274 * flushing. 275 * 276 * Drivers can use this as their &drm_mode_config_funcs.fb_create callback. 277 * The ADDFB2 IOCTL calls into this callback. 278 * 279 * Returns: 280 * Pointer to a &drm_framebuffer on success or an error pointer on failure. 281 */ 282 struct drm_framebuffer * 283 drm_gem_fb_create(struct drm_device *dev, struct drm_file *file, 284 const struct drm_mode_fb_cmd2 *mode_cmd) 285 { 286 return drm_gem_fb_create_with_funcs(dev, file, mode_cmd, 287 &drm_gem_fb_funcs); 288 } 289 EXPORT_SYMBOL_GPL(drm_gem_fb_create); 290 291 static const struct drm_framebuffer_funcs drm_gem_fb_funcs_dirtyfb = { 292 .destroy = drm_gem_fb_destroy, 293 .create_handle = drm_gem_fb_create_handle, 294 .dirty = drm_atomic_helper_dirtyfb, 295 }; 296 297 /** 298 * drm_gem_fb_create_with_dirty() - Helper function for the 299 * &drm_mode_config_funcs.fb_create callback 300 * @dev: DRM device 301 * @file: DRM file that holds the GEM handle(s) backing the framebuffer 302 * @mode_cmd: Metadata from the userspace framebuffer creation request 303 * 304 * This function creates a new framebuffer object described by 305 * &drm_mode_fb_cmd2. This description includes handles for the buffer(s) 306 * backing the framebuffer. drm_atomic_helper_dirtyfb() is used for the dirty 307 * callback giving framebuffer flushing through the atomic machinery. Use 308 * drm_gem_fb_create() if you don't need the dirty callback. 309 * The function does buffer size validation. 310 * 311 * Drivers should also call drm_plane_enable_fb_damage_clips() on all planes 312 * to enable userspace to use damage clips also with the ATOMIC IOCTL. 313 * 314 * Drivers can use this as their &drm_mode_config_funcs.fb_create callback. 315 * The ADDFB2 IOCTL calls into this callback. 316 * 317 * Returns: 318 * Pointer to a &drm_framebuffer on success or an error pointer on failure. 319 */ 320 struct drm_framebuffer * 321 drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file, 322 const struct drm_mode_fb_cmd2 *mode_cmd) 323 { 324 return drm_gem_fb_create_with_funcs(dev, file, mode_cmd, 325 &drm_gem_fb_funcs_dirtyfb); 326 } 327 EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty); 328 329 /** 330 * drm_gem_fb_vmap - maps all framebuffer BOs into kernel address space 331 * @fb: the framebuffer 332 * @map: returns the mapping's address for each BO 333 * @data: returns the data address for each BO, can be NULL 334 * 335 * This function maps all buffer objects of the given framebuffer into 336 * kernel address space and stores them in struct iosys_map. If the 337 * mapping operation fails for one of the BOs, the function unmaps the 338 * already established mappings automatically. 339 * 340 * Callers that want to access a BO's stored data should pass @data. 341 * The argument returns the addresses of the data stored in each BO. This 342 * is different from @map if the framebuffer's offsets field is non-zero. 343 * 344 * Both, @map and @data, must each refer to arrays with at least 345 * fb->format->num_planes elements. 346 * 347 * See drm_gem_fb_vunmap() for unmapping. 348 * 349 * Returns: 350 * 0 on success, or a negative errno code otherwise. 351 */ 352 int drm_gem_fb_vmap(struct drm_framebuffer *fb, struct iosys_map *map, 353 struct iosys_map *data) 354 { 355 struct drm_gem_object *obj; 356 unsigned int i; 357 int ret; 358 359 for (i = 0; i < fb->format->num_planes; ++i) { 360 obj = drm_gem_fb_get_obj(fb, i); 361 if (!obj) { 362 ret = -EINVAL; 363 goto err_drm_gem_vunmap; 364 } 365 ret = drm_gem_vmap_unlocked(obj, &map[i]); 366 if (ret) 367 goto err_drm_gem_vunmap; 368 } 369 370 if (data) { 371 for (i = 0; i < fb->format->num_planes; ++i) { 372 memcpy(&data[i], &map[i], sizeof(data[i])); 373 if (iosys_map_is_null(&data[i])) 374 continue; 375 iosys_map_incr(&data[i], fb->offsets[i]); 376 } 377 } 378 379 return 0; 380 381 err_drm_gem_vunmap: 382 while (i) { 383 --i; 384 obj = drm_gem_fb_get_obj(fb, i); 385 if (!obj) 386 continue; 387 drm_gem_vunmap_unlocked(obj, &map[i]); 388 } 389 return ret; 390 } 391 EXPORT_SYMBOL(drm_gem_fb_vmap); 392 393 /** 394 * drm_gem_fb_vunmap - unmaps framebuffer BOs from kernel address space 395 * @fb: the framebuffer 396 * @map: mapping addresses as returned by drm_gem_fb_vmap() 397 * 398 * This function unmaps all buffer objects of the given framebuffer. 399 * 400 * See drm_gem_fb_vmap() for more information. 401 */ 402 void drm_gem_fb_vunmap(struct drm_framebuffer *fb, struct iosys_map *map) 403 { 404 unsigned int i = fb->format->num_planes; 405 struct drm_gem_object *obj; 406 407 while (i) { 408 --i; 409 obj = drm_gem_fb_get_obj(fb, i); 410 if (!obj) 411 continue; 412 if (iosys_map_is_null(&map[i])) 413 continue; 414 drm_gem_vunmap_unlocked(obj, &map[i]); 415 } 416 } 417 EXPORT_SYMBOL(drm_gem_fb_vunmap); 418 419 static void __drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir, 420 unsigned int num_planes) 421 { 422 struct dma_buf_attachment *import_attach; 423 struct drm_gem_object *obj; 424 int ret; 425 426 while (num_planes) { 427 --num_planes; 428 obj = drm_gem_fb_get_obj(fb, num_planes); 429 if (!obj) 430 continue; 431 import_attach = obj->import_attach; 432 if (!import_attach) 433 continue; 434 ret = dma_buf_end_cpu_access(import_attach->dmabuf, 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 dma_buf_attachment *import_attach; 458 struct drm_gem_object *obj; 459 unsigned int i; 460 int ret; 461 462 for (i = 0; i < fb->format->num_planes; ++i) { 463 obj = drm_gem_fb_get_obj(fb, i); 464 if (!obj) { 465 ret = -EINVAL; 466 goto err___drm_gem_fb_end_cpu_access; 467 } 468 import_attach = obj->import_attach; 469 if (!import_attach) 470 continue; 471 ret = dma_buf_begin_cpu_access(import_attach->dmabuf, dir); 472 if (ret) 473 goto err___drm_gem_fb_end_cpu_access; 474 } 475 476 return 0; 477 478 err___drm_gem_fb_end_cpu_access: 479 __drm_gem_fb_end_cpu_access(fb, dir, i); 480 return ret; 481 } 482 EXPORT_SYMBOL(drm_gem_fb_begin_cpu_access); 483 484 /** 485 * drm_gem_fb_end_cpu_access - signals end of CPU access to GEM buffer objects 486 * @fb: the framebuffer 487 * @dir: access mode 488 * 489 * Signals the end of CPU access to the given framebuffer's GEM buffer objects. This 490 * function must be paired with a corresponding call to drm_gem_fb_begin_cpu_access(). 491 * For imported BOs, the function calls dma_buf_end_cpu_access(). 492 * 493 * See also drm_gem_fb_begin_cpu_access(). 494 */ 495 void drm_gem_fb_end_cpu_access(struct drm_framebuffer *fb, enum dma_data_direction dir) 496 { 497 __drm_gem_fb_end_cpu_access(fb, dir, fb->format->num_planes); 498 } 499 EXPORT_SYMBOL(drm_gem_fb_end_cpu_access); 500 501 // TODO Drop this function and replace by drm_format_info_bpp() once all 502 // DRM_FORMAT_* provide proper block info in drivers/gpu/drm/drm_fourcc.c 503 static __u32 drm_gem_afbc_get_bpp(struct drm_device *dev, 504 const struct drm_mode_fb_cmd2 *mode_cmd) 505 { 506 const struct drm_format_info *info; 507 508 info = drm_get_format_info(dev, mode_cmd); 509 510 switch (info->format) { 511 case DRM_FORMAT_YUV420_8BIT: 512 return 12; 513 case DRM_FORMAT_YUV420_10BIT: 514 return 15; 515 case DRM_FORMAT_VUY101010: 516 return 30; 517 default: 518 return drm_format_info_bpp(info, 0); 519 } 520 } 521 522 static int drm_gem_afbc_min_size(struct drm_device *dev, 523 const struct drm_mode_fb_cmd2 *mode_cmd, 524 struct drm_afbc_framebuffer *afbc_fb) 525 { 526 __u32 n_blocks, w_alignment, h_alignment, hdr_alignment; 527 /* remove bpp when all users properly encode cpp in drm_format_info */ 528 __u32 bpp; 529 530 switch (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK) { 531 case AFBC_FORMAT_MOD_BLOCK_SIZE_16x16: 532 afbc_fb->block_width = 16; 533 afbc_fb->block_height = 16; 534 break; 535 case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8: 536 afbc_fb->block_width = 32; 537 afbc_fb->block_height = 8; 538 break; 539 /* no user exists yet - fall through */ 540 case AFBC_FORMAT_MOD_BLOCK_SIZE_64x4: 541 case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8_64x4: 542 default: 543 drm_dbg_kms(dev, "Invalid AFBC_FORMAT_MOD_BLOCK_SIZE: %lld.\n", 544 mode_cmd->modifier[0] 545 & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK); 546 return -EINVAL; 547 } 548 549 /* tiled header afbc */ 550 w_alignment = afbc_fb->block_width; 551 h_alignment = afbc_fb->block_height; 552 hdr_alignment = AFBC_HDR_ALIGN; 553 if (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_TILED) { 554 w_alignment *= AFBC_TH_LAYOUT_ALIGNMENT; 555 h_alignment *= AFBC_TH_LAYOUT_ALIGNMENT; 556 hdr_alignment = AFBC_TH_BODY_START_ALIGNMENT; 557 } 558 559 afbc_fb->aligned_width = ALIGN(mode_cmd->width, w_alignment); 560 afbc_fb->aligned_height = ALIGN(mode_cmd->height, h_alignment); 561 afbc_fb->offset = mode_cmd->offsets[0]; 562 563 bpp = drm_gem_afbc_get_bpp(dev, mode_cmd); 564 if (!bpp) { 565 drm_dbg_kms(dev, "Invalid AFBC bpp value: %d\n", bpp); 566 return -EINVAL; 567 } 568 569 n_blocks = (afbc_fb->aligned_width * afbc_fb->aligned_height) 570 / AFBC_SUPERBLOCK_PIXELS; 571 afbc_fb->afbc_size = ALIGN(n_blocks * AFBC_HEADER_SIZE, hdr_alignment); 572 afbc_fb->afbc_size += n_blocks * ALIGN(bpp * AFBC_SUPERBLOCK_PIXELS / 8, 573 AFBC_SUPERBLOCK_ALIGNMENT); 574 575 return 0; 576 } 577 578 /** 579 * drm_gem_fb_afbc_init() - Helper function for drivers using afbc to 580 * fill and validate all the afbc-specific 581 * struct drm_afbc_framebuffer members 582 * 583 * @dev: DRM device 584 * @afbc_fb: afbc-specific framebuffer 585 * @mode_cmd: Metadata from the userspace framebuffer creation request 586 * @afbc_fb: afbc framebuffer 587 * 588 * This function can be used by drivers which support afbc to complete 589 * the preparation of struct drm_afbc_framebuffer. It must be called after 590 * allocating the said struct and calling drm_gem_fb_init_with_funcs(). 591 * It is caller's responsibility to put afbc_fb->base.obj objects in case 592 * the call is unsuccessful. 593 * 594 * Returns: 595 * Zero on success or a negative error value on failure. 596 */ 597 int drm_gem_fb_afbc_init(struct drm_device *dev, 598 const struct drm_mode_fb_cmd2 *mode_cmd, 599 struct drm_afbc_framebuffer *afbc_fb) 600 { 601 const struct drm_format_info *info; 602 struct drm_gem_object **objs; 603 int ret; 604 605 objs = afbc_fb->base.obj; 606 info = drm_get_format_info(dev, mode_cmd); 607 if (!info) 608 return -EINVAL; 609 610 ret = drm_gem_afbc_min_size(dev, mode_cmd, afbc_fb); 611 if (ret < 0) 612 return ret; 613 614 if (objs[0]->size < afbc_fb->afbc_size) 615 return -EINVAL; 616 617 return 0; 618 } 619 EXPORT_SYMBOL_GPL(drm_gem_fb_afbc_init); 620