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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
21MODULE_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 */
53struct 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}
65EXPORT_SYMBOL_GPL(drm_gem_fb_get_obj);
66
67static int
68drm_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 */
97void 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}
107EXPORT_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 */
122int 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}
127EXPORT_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 */
151int 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
208err_gem_object_put:
209 while (i > 0) {
210 --i;
211 drm_gem_object_put(objs[i]);
212 }
213 return ret;
214}
215EXPORT_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 */
233struct drm_framebuffer *
234drm_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}
253EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_funcs);
254
255static 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 */
282struct drm_framebuffer *
283drm_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}
289EXPORT_SYMBOL_GPL(drm_gem_fb_create);
290
291static 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 */
320struct drm_framebuffer *
321drm_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}
327EXPORT_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 */
352int 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
381err_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}
391EXPORT_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 */
402void 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}
417EXPORT_SYMBOL(drm_gem_fb_vunmap);
418
419static 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 */
455int 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
478err___drm_gem_fb_end_cpu_access:
479 __drm_gem_fb_end_cpu_access(fb, dir, i);
480 return ret;
481}
482EXPORT_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 */
495void 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}
499EXPORT_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
503static __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
522static 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 */
597int 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}
619EXPORT_SYMBOL_GPL(drm_gem_fb_afbc_init);
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
10#include <drm/drm_damage_helper.h>
11#include <drm/drm_fb_helper.h>
12#include <drm/drm_fourcc.h>
13#include <drm/drm_framebuffer.h>
14#include <drm/drm_gem.h>
15#include <drm/drm_gem_framebuffer_helper.h>
16#include <drm/drm_modeset_helper.h>
17
18#define AFBC_HEADER_SIZE 16
19#define AFBC_TH_LAYOUT_ALIGNMENT 8
20#define AFBC_HDR_ALIGN 64
21#define AFBC_SUPERBLOCK_PIXELS 256
22#define AFBC_SUPERBLOCK_ALIGNMENT 128
23#define AFBC_TH_BODY_START_ALIGNMENT 4096
24
25/**
26 * DOC: overview
27 *
28 * This library provides helpers for drivers that don't subclass
29 * &drm_framebuffer and use &drm_gem_object for their backing storage.
30 *
31 * Drivers without additional needs to validate framebuffers can simply use
32 * drm_gem_fb_create() and everything is wired up automatically. Other drivers
33 * can use all parts independently.
34 */
35
36/**
37 * drm_gem_fb_get_obj() - Get GEM object backing the framebuffer
38 * @fb: Framebuffer
39 * @plane: Plane index
40 *
41 * No additional reference is taken beyond the one that the &drm_frambuffer
42 * already holds.
43 *
44 * Returns:
45 * Pointer to &drm_gem_object for the given framebuffer and plane index or NULL
46 * if it does not exist.
47 */
48struct drm_gem_object *drm_gem_fb_get_obj(struct drm_framebuffer *fb,
49 unsigned int plane)
50{
51 if (plane >= 4)
52 return NULL;
53
54 return fb->obj[plane];
55}
56EXPORT_SYMBOL_GPL(drm_gem_fb_get_obj);
57
58static int
59drm_gem_fb_init(struct drm_device *dev,
60 struct drm_framebuffer *fb,
61 const struct drm_mode_fb_cmd2 *mode_cmd,
62 struct drm_gem_object **obj, unsigned int num_planes,
63 const struct drm_framebuffer_funcs *funcs)
64{
65 int ret, i;
66
67 drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd);
68
69 for (i = 0; i < num_planes; i++)
70 fb->obj[i] = obj[i];
71
72 ret = drm_framebuffer_init(dev, fb, funcs);
73 if (ret)
74 drm_err(dev, "Failed to init framebuffer: %d\n", ret);
75
76 return ret;
77}
78
79/**
80 * drm_gem_fb_destroy - Free GEM backed framebuffer
81 * @fb: Framebuffer
82 *
83 * Frees a GEM backed framebuffer with its backing buffer(s) and the structure
84 * itself. Drivers can use this as their &drm_framebuffer_funcs->destroy
85 * callback.
86 */
87void drm_gem_fb_destroy(struct drm_framebuffer *fb)
88{
89 int i;
90
91 for (i = 0; i < 4; i++)
92 drm_gem_object_put(fb->obj[i]);
93
94 drm_framebuffer_cleanup(fb);
95 kfree(fb);
96}
97EXPORT_SYMBOL(drm_gem_fb_destroy);
98
99/**
100 * drm_gem_fb_create_handle - Create handle for GEM backed framebuffer
101 * @fb: Framebuffer
102 * @file: DRM file to register the handle for
103 * @handle: Pointer to return the created handle
104 *
105 * This function creates a handle for the GEM object backing the framebuffer.
106 * Drivers can use this as their &drm_framebuffer_funcs->create_handle
107 * callback. The GETFB IOCTL calls into this callback.
108 *
109 * Returns:
110 * 0 on success or a negative error code on failure.
111 */
112int drm_gem_fb_create_handle(struct drm_framebuffer *fb, struct drm_file *file,
113 unsigned int *handle)
114{
115 return drm_gem_handle_create(file, fb->obj[0], handle);
116}
117EXPORT_SYMBOL(drm_gem_fb_create_handle);
118
119/**
120 * drm_gem_fb_init_with_funcs() - Helper function for implementing
121 * &drm_mode_config_funcs.fb_create
122 * callback in cases when the driver
123 * allocates a subclass of
124 * struct drm_framebuffer
125 * @dev: DRM device
126 * @fb: framebuffer object
127 * @file: DRM file that holds the GEM handle(s) backing the framebuffer
128 * @mode_cmd: Metadata from the userspace framebuffer creation request
129 * @funcs: vtable to be used for the new framebuffer object
130 *
131 * This function can be used to set &drm_framebuffer_funcs for drivers that need
132 * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to
133 * change &drm_framebuffer_funcs. The function does buffer size validation.
134 * The buffer size validation is for a general case, though, so users should
135 * pay attention to the checks being appropriate for them or, at least,
136 * non-conflicting.
137 *
138 * Returns:
139 * Zero or a negative error code.
140 */
141int drm_gem_fb_init_with_funcs(struct drm_device *dev,
142 struct drm_framebuffer *fb,
143 struct drm_file *file,
144 const struct drm_mode_fb_cmd2 *mode_cmd,
145 const struct drm_framebuffer_funcs *funcs)
146{
147 const struct drm_format_info *info;
148 struct drm_gem_object *objs[4];
149 int ret, i;
150
151 info = drm_get_format_info(dev, mode_cmd);
152 if (!info) {
153 drm_dbg_kms(dev, "Failed to get FB format info\n");
154 return -EINVAL;
155 }
156
157 for (i = 0; i < info->num_planes; i++) {
158 unsigned int width = mode_cmd->width / (i ? info->hsub : 1);
159 unsigned int height = mode_cmd->height / (i ? info->vsub : 1);
160 unsigned int min_size;
161
162 objs[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]);
163 if (!objs[i]) {
164 drm_dbg_kms(dev, "Failed to lookup GEM object\n");
165 ret = -ENOENT;
166 goto err_gem_object_put;
167 }
168
169 min_size = (height - 1) * mode_cmd->pitches[i]
170 + drm_format_info_min_pitch(info, i, width)
171 + mode_cmd->offsets[i];
172
173 if (objs[i]->size < min_size) {
174 drm_dbg_kms(dev,
175 "GEM object size (%zu) smaller than minimum size (%u) for plane %d\n",
176 objs[i]->size, min_size, i);
177 drm_gem_object_put(objs[i]);
178 ret = -EINVAL;
179 goto err_gem_object_put;
180 }
181 }
182
183 ret = drm_gem_fb_init(dev, fb, mode_cmd, objs, i, funcs);
184 if (ret)
185 goto err_gem_object_put;
186
187 return 0;
188
189err_gem_object_put:
190 for (i--; i >= 0; i--)
191 drm_gem_object_put(objs[i]);
192
193 return ret;
194}
195EXPORT_SYMBOL_GPL(drm_gem_fb_init_with_funcs);
196
197/**
198 * drm_gem_fb_create_with_funcs() - Helper function for the
199 * &drm_mode_config_funcs.fb_create
200 * callback
201 * @dev: DRM device
202 * @file: DRM file that holds the GEM handle(s) backing the framebuffer
203 * @mode_cmd: Metadata from the userspace framebuffer creation request
204 * @funcs: vtable to be used for the new framebuffer object
205 *
206 * This function can be used to set &drm_framebuffer_funcs for drivers that need
207 * custom framebuffer callbacks. Use drm_gem_fb_create() if you don't need to
208 * change &drm_framebuffer_funcs. The function does buffer size validation.
209 *
210 * Returns:
211 * Pointer to a &drm_framebuffer on success or an error pointer on failure.
212 */
213struct drm_framebuffer *
214drm_gem_fb_create_with_funcs(struct drm_device *dev, struct drm_file *file,
215 const struct drm_mode_fb_cmd2 *mode_cmd,
216 const struct drm_framebuffer_funcs *funcs)
217{
218 struct drm_framebuffer *fb;
219 int ret;
220
221 fb = kzalloc(sizeof(*fb), GFP_KERNEL);
222 if (!fb)
223 return ERR_PTR(-ENOMEM);
224
225 ret = drm_gem_fb_init_with_funcs(dev, fb, file, mode_cmd, funcs);
226 if (ret) {
227 kfree(fb);
228 return ERR_PTR(ret);
229 }
230
231 return fb;
232}
233EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_funcs);
234
235static const struct drm_framebuffer_funcs drm_gem_fb_funcs = {
236 .destroy = drm_gem_fb_destroy,
237 .create_handle = drm_gem_fb_create_handle,
238};
239
240/**
241 * drm_gem_fb_create() - Helper function for the
242 * &drm_mode_config_funcs.fb_create callback
243 * @dev: DRM device
244 * @file: DRM file that holds the GEM handle(s) backing the framebuffer
245 * @mode_cmd: Metadata from the userspace framebuffer creation request
246 *
247 * This function creates a new framebuffer object described by
248 * &drm_mode_fb_cmd2. This description includes handles for the buffer(s)
249 * backing the framebuffer.
250 *
251 * If your hardware has special alignment or pitch requirements these should be
252 * checked before calling this function. The function does buffer size
253 * validation. Use drm_gem_fb_create_with_dirty() if you need framebuffer
254 * flushing.
255 *
256 * Drivers can use this as their &drm_mode_config_funcs.fb_create callback.
257 * The ADDFB2 IOCTL calls into this callback.
258 *
259 * Returns:
260 * Pointer to a &drm_framebuffer on success or an error pointer on failure.
261 */
262struct drm_framebuffer *
263drm_gem_fb_create(struct drm_device *dev, struct drm_file *file,
264 const struct drm_mode_fb_cmd2 *mode_cmd)
265{
266 return drm_gem_fb_create_with_funcs(dev, file, mode_cmd,
267 &drm_gem_fb_funcs);
268}
269EXPORT_SYMBOL_GPL(drm_gem_fb_create);
270
271static const struct drm_framebuffer_funcs drm_gem_fb_funcs_dirtyfb = {
272 .destroy = drm_gem_fb_destroy,
273 .create_handle = drm_gem_fb_create_handle,
274 .dirty = drm_atomic_helper_dirtyfb,
275};
276
277/**
278 * drm_gem_fb_create_with_dirty() - Helper function for the
279 * &drm_mode_config_funcs.fb_create callback
280 * @dev: DRM device
281 * @file: DRM file that holds the GEM handle(s) backing the framebuffer
282 * @mode_cmd: Metadata from the userspace framebuffer creation request
283 *
284 * This function creates a new framebuffer object described by
285 * &drm_mode_fb_cmd2. This description includes handles for the buffer(s)
286 * backing the framebuffer. drm_atomic_helper_dirtyfb() is used for the dirty
287 * callback giving framebuffer flushing through the atomic machinery. Use
288 * drm_gem_fb_create() if you don't need the dirty callback.
289 * The function does buffer size validation.
290 *
291 * Drivers should also call drm_plane_enable_fb_damage_clips() on all planes
292 * to enable userspace to use damage clips also with the ATOMIC IOCTL.
293 *
294 * Drivers can use this as their &drm_mode_config_funcs.fb_create callback.
295 * The ADDFB2 IOCTL calls into this callback.
296 *
297 * Returns:
298 * Pointer to a &drm_framebuffer on success or an error pointer on failure.
299 */
300struct drm_framebuffer *
301drm_gem_fb_create_with_dirty(struct drm_device *dev, struct drm_file *file,
302 const struct drm_mode_fb_cmd2 *mode_cmd)
303{
304 return drm_gem_fb_create_with_funcs(dev, file, mode_cmd,
305 &drm_gem_fb_funcs_dirtyfb);
306}
307EXPORT_SYMBOL_GPL(drm_gem_fb_create_with_dirty);
308
309static __u32 drm_gem_afbc_get_bpp(struct drm_device *dev,
310 const struct drm_mode_fb_cmd2 *mode_cmd)
311{
312 const struct drm_format_info *info;
313
314 info = drm_get_format_info(dev, mode_cmd);
315
316 /* use whatever a driver has set */
317 if (info->cpp[0])
318 return info->cpp[0] * 8;
319
320 /* guess otherwise */
321 switch (info->format) {
322 case DRM_FORMAT_YUV420_8BIT:
323 return 12;
324 case DRM_FORMAT_YUV420_10BIT:
325 return 15;
326 case DRM_FORMAT_VUY101010:
327 return 30;
328 default:
329 break;
330 }
331
332 /* all attempts failed */
333 return 0;
334}
335
336static int drm_gem_afbc_min_size(struct drm_device *dev,
337 const struct drm_mode_fb_cmd2 *mode_cmd,
338 struct drm_afbc_framebuffer *afbc_fb)
339{
340 __u32 n_blocks, w_alignment, h_alignment, hdr_alignment;
341 /* remove bpp when all users properly encode cpp in drm_format_info */
342 __u32 bpp;
343
344 switch (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK) {
345 case AFBC_FORMAT_MOD_BLOCK_SIZE_16x16:
346 afbc_fb->block_width = 16;
347 afbc_fb->block_height = 16;
348 break;
349 case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8:
350 afbc_fb->block_width = 32;
351 afbc_fb->block_height = 8;
352 break;
353 /* no user exists yet - fall through */
354 case AFBC_FORMAT_MOD_BLOCK_SIZE_64x4:
355 case AFBC_FORMAT_MOD_BLOCK_SIZE_32x8_64x4:
356 default:
357 drm_dbg_kms(dev, "Invalid AFBC_FORMAT_MOD_BLOCK_SIZE: %lld.\n",
358 mode_cmd->modifier[0]
359 & AFBC_FORMAT_MOD_BLOCK_SIZE_MASK);
360 return -EINVAL;
361 }
362
363 /* tiled header afbc */
364 w_alignment = afbc_fb->block_width;
365 h_alignment = afbc_fb->block_height;
366 hdr_alignment = AFBC_HDR_ALIGN;
367 if (mode_cmd->modifier[0] & AFBC_FORMAT_MOD_TILED) {
368 w_alignment *= AFBC_TH_LAYOUT_ALIGNMENT;
369 h_alignment *= AFBC_TH_LAYOUT_ALIGNMENT;
370 hdr_alignment = AFBC_TH_BODY_START_ALIGNMENT;
371 }
372
373 afbc_fb->aligned_width = ALIGN(mode_cmd->width, w_alignment);
374 afbc_fb->aligned_height = ALIGN(mode_cmd->height, h_alignment);
375 afbc_fb->offset = mode_cmd->offsets[0];
376
377 bpp = drm_gem_afbc_get_bpp(dev, mode_cmd);
378 if (!bpp) {
379 drm_dbg_kms(dev, "Invalid AFBC bpp value: %d\n", bpp);
380 return -EINVAL;
381 }
382
383 n_blocks = (afbc_fb->aligned_width * afbc_fb->aligned_height)
384 / AFBC_SUPERBLOCK_PIXELS;
385 afbc_fb->afbc_size = ALIGN(n_blocks * AFBC_HEADER_SIZE, hdr_alignment);
386 afbc_fb->afbc_size += n_blocks * ALIGN(bpp * AFBC_SUPERBLOCK_PIXELS / 8,
387 AFBC_SUPERBLOCK_ALIGNMENT);
388
389 return 0;
390}
391
392/**
393 * drm_gem_fb_afbc_init() - Helper function for drivers using afbc to
394 * fill and validate all the afbc-specific
395 * struct drm_afbc_framebuffer members
396 *
397 * @dev: DRM device
398 * @afbc_fb: afbc-specific framebuffer
399 * @mode_cmd: Metadata from the userspace framebuffer creation request
400 * @afbc_fb: afbc framebuffer
401 *
402 * This function can be used by drivers which support afbc to complete
403 * the preparation of struct drm_afbc_framebuffer. It must be called after
404 * allocating the said struct and calling drm_gem_fb_init_with_funcs().
405 * It is caller's responsibility to put afbc_fb->base.obj objects in case
406 * the call is unsuccessful.
407 *
408 * Returns:
409 * Zero on success or a negative error value on failure.
410 */
411int drm_gem_fb_afbc_init(struct drm_device *dev,
412 const struct drm_mode_fb_cmd2 *mode_cmd,
413 struct drm_afbc_framebuffer *afbc_fb)
414{
415 const struct drm_format_info *info;
416 struct drm_gem_object **objs;
417 int ret;
418
419 objs = afbc_fb->base.obj;
420 info = drm_get_format_info(dev, mode_cmd);
421 if (!info)
422 return -EINVAL;
423
424 ret = drm_gem_afbc_min_size(dev, mode_cmd, afbc_fb);
425 if (ret < 0)
426 return ret;
427
428 if (objs[0]->size < afbc_fb->afbc_size)
429 return -EINVAL;
430
431 return 0;
432}
433EXPORT_SYMBOL_GPL(drm_gem_fb_afbc_init);