1 /*
2  * Copyright 2009 Jerome Glisse.
3  * All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the
7  * "Software"), to deal in the Software without restriction, including
8  * without limitation the rights to use, copy, modify, merge, publish,
9  * distribute, sub license, and/or sell copies of the Software, and to
10  * permit persons to whom the Software is furnished to do so, subject to
11  * the following conditions:
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
16  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
17  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
18  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
19  * USE OR OTHER DEALINGS IN THE SOFTWARE.
20  *
21  * The above copyright notice and this permission notice (including the
22  * next paragraph) shall be included in all copies or substantial portions
23  * of the Software.
24  *
25  */
26 /*
27  * Authors:
28  *    Jerome Glisse <glisse@freedesktop.org>
29  *    Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
30  *    Dave Airlie
31  */
32 #include <ttm/ttm_bo_api.h>
33 #include <ttm/ttm_bo_driver.h>
34 #include <ttm/ttm_placement.h>
35 #include <ttm/ttm_module.h>
36 #include <drm/drmP.h>
37 #include <drm/radeon_drm.h>
38 #include "radeon_reg.h"
39 #include "radeon.h"
40 
41 #define DRM_FILE_PAGE_OFFSET (0x100000000ULL >> PAGE_SHIFT)
42 
43 static struct radeon_device *radeon_get_rdev(struct ttm_bo_device *bdev)
44 {
45 	struct radeon_mman *mman;
46 	struct radeon_device *rdev;
47 
48 	mman = container_of(bdev, struct radeon_mman, bdev);
49 	rdev = container_of(mman, struct radeon_device, mman);
50 	return rdev;
51 }
52 
53 
54 /*
55  * Global memory.
56  */
57 static int radeon_ttm_mem_global_init(struct ttm_global_reference *ref)
58 {
59 	return ttm_mem_global_init(ref->object);
60 }
61 
62 static void radeon_ttm_mem_global_release(struct ttm_global_reference *ref)
63 {
64 	ttm_mem_global_release(ref->object);
65 }
66 
67 static int radeon_ttm_global_init(struct radeon_device *rdev)
68 {
69 	struct ttm_global_reference *global_ref;
70 	int r;
71 
72 	rdev->mman.mem_global_referenced = false;
73 	global_ref = &rdev->mman.mem_global_ref;
74 	global_ref->global_type = TTM_GLOBAL_TTM_MEM;
75 	global_ref->size = sizeof(struct ttm_mem_global);
76 	global_ref->init = &radeon_ttm_mem_global_init;
77 	global_ref->release = &radeon_ttm_mem_global_release;
78 	r = ttm_global_item_ref(global_ref);
79 	if (r != 0) {
80 		DRM_ERROR("Failed referencing a global TTM memory object.\n");
81 		return r;
82 	}
83 	rdev->mman.mem_global_referenced = true;
84 	return 0;
85 }
86 
87 static void radeon_ttm_global_fini(struct radeon_device *rdev)
88 {
89 	if (rdev->mman.mem_global_referenced) {
90 		ttm_global_item_unref(&rdev->mman.mem_global_ref);
91 		rdev->mman.mem_global_referenced = false;
92 	}
93 }
94 
95 struct ttm_backend *radeon_ttm_backend_create(struct radeon_device *rdev);
96 
97 static struct ttm_backend*
98 radeon_create_ttm_backend_entry(struct ttm_bo_device *bdev)
99 {
100 	struct radeon_device *rdev;
101 
102 	rdev = radeon_get_rdev(bdev);
103 #if __OS_HAS_AGP
104 	if (rdev->flags & RADEON_IS_AGP) {
105 		return ttm_agp_backend_init(bdev, rdev->ddev->agp->bridge);
106 	} else
107 #endif
108 	{
109 		return radeon_ttm_backend_create(rdev);
110 	}
111 }
112 
113 static int radeon_invalidate_caches(struct ttm_bo_device *bdev, uint32_t flags)
114 {
115 	return 0;
116 }
117 
118 static int radeon_init_mem_type(struct ttm_bo_device *bdev, uint32_t type,
119 				struct ttm_mem_type_manager *man)
120 {
121 	struct radeon_device *rdev;
122 
123 	rdev = radeon_get_rdev(bdev);
124 
125 	switch (type) {
126 	case TTM_PL_SYSTEM:
127 		/* System memory */
128 		man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
129 		man->available_caching = TTM_PL_MASK_CACHING;
130 		man->default_caching = TTM_PL_FLAG_CACHED;
131 		break;
132 	case TTM_PL_TT:
133 		man->gpu_offset = 0;
134 		man->available_caching = TTM_PL_MASK_CACHING;
135 		man->default_caching = TTM_PL_FLAG_CACHED;
136 		man->flags = TTM_MEMTYPE_FLAG_MAPPABLE | TTM_MEMTYPE_FLAG_CMA;
137 #if __OS_HAS_AGP
138 		if (rdev->flags & RADEON_IS_AGP) {
139 			if (!(drm_core_has_AGP(rdev->ddev) && rdev->ddev->agp)) {
140 				DRM_ERROR("AGP is not enabled for memory type %u\n",
141 					  (unsigned)type);
142 				return -EINVAL;
143 			}
144 			man->io_offset = rdev->mc.agp_base;
145 			man->io_size = rdev->mc.gtt_size;
146 			man->io_addr = NULL;
147 			if (!rdev->ddev->agp->cant_use_aperture)
148 				man->flags = TTM_MEMTYPE_FLAG_NEEDS_IOREMAP |
149 					     TTM_MEMTYPE_FLAG_MAPPABLE;
150 			man->available_caching = TTM_PL_FLAG_UNCACHED |
151 						 TTM_PL_FLAG_WC;
152 			man->default_caching = TTM_PL_FLAG_WC;
153 		} else
154 #endif
155 		{
156 			man->io_offset = 0;
157 			man->io_size = 0;
158 			man->io_addr = NULL;
159 		}
160 		break;
161 	case TTM_PL_VRAM:
162 		/* "On-card" video ram */
163 		man->gpu_offset = 0;
164 		man->flags = TTM_MEMTYPE_FLAG_FIXED |
165 			     TTM_MEMTYPE_FLAG_NEEDS_IOREMAP |
166 			     TTM_MEMTYPE_FLAG_MAPPABLE;
167 		man->available_caching = TTM_PL_FLAG_UNCACHED | TTM_PL_FLAG_WC;
168 		man->default_caching = TTM_PL_FLAG_WC;
169 		man->io_addr = NULL;
170 		man->io_offset = rdev->mc.aper_base;
171 		man->io_size = rdev->mc.aper_size;
172 		break;
173 	default:
174 		DRM_ERROR("Unsupported memory type %u\n", (unsigned)type);
175 		return -EINVAL;
176 	}
177 	return 0;
178 }
179 
180 static uint32_t radeon_evict_flags(struct ttm_buffer_object *bo)
181 {
182 	uint32_t cur_placement = bo->mem.placement & ~TTM_PL_MASK_MEMTYPE;
183 
184 	switch (bo->mem.mem_type) {
185 	default:
186 		return (cur_placement & ~TTM_PL_MASK_CACHING) |
187 			TTM_PL_FLAG_SYSTEM |
188 			TTM_PL_FLAG_CACHED;
189 	}
190 }
191 
192 static int radeon_verify_access(struct ttm_buffer_object *bo, struct file *filp)
193 {
194 	return 0;
195 }
196 
197 static void radeon_move_null(struct ttm_buffer_object *bo,
198 			     struct ttm_mem_reg *new_mem)
199 {
200 	struct ttm_mem_reg *old_mem = &bo->mem;
201 
202 	BUG_ON(old_mem->mm_node != NULL);
203 	*old_mem = *new_mem;
204 	new_mem->mm_node = NULL;
205 }
206 
207 static int radeon_move_blit(struct ttm_buffer_object *bo,
208 			    bool evict, int no_wait,
209 			    struct ttm_mem_reg *new_mem,
210 			    struct ttm_mem_reg *old_mem)
211 {
212 	struct radeon_device *rdev;
213 	uint64_t old_start, new_start;
214 	struct radeon_fence *fence;
215 	int r;
216 
217 	rdev = radeon_get_rdev(bo->bdev);
218 	r = radeon_fence_create(rdev, &fence);
219 	if (unlikely(r)) {
220 		return r;
221 	}
222 	old_start = old_mem->mm_node->start << PAGE_SHIFT;
223 	new_start = new_mem->mm_node->start << PAGE_SHIFT;
224 
225 	switch (old_mem->mem_type) {
226 	case TTM_PL_VRAM:
227 		old_start += rdev->mc.vram_location;
228 		break;
229 	case TTM_PL_TT:
230 		old_start += rdev->mc.gtt_location;
231 		break;
232 	default:
233 		DRM_ERROR("Unknown placement %d\n", old_mem->mem_type);
234 		return -EINVAL;
235 	}
236 	switch (new_mem->mem_type) {
237 	case TTM_PL_VRAM:
238 		new_start += rdev->mc.vram_location;
239 		break;
240 	case TTM_PL_TT:
241 		new_start += rdev->mc.gtt_location;
242 		break;
243 	default:
244 		DRM_ERROR("Unknown placement %d\n", old_mem->mem_type);
245 		return -EINVAL;
246 	}
247 	if (!rdev->cp.ready) {
248 		DRM_ERROR("Trying to move memory with CP turned off.\n");
249 		return -EINVAL;
250 	}
251 	r = radeon_copy(rdev, old_start, new_start, new_mem->num_pages, fence);
252 	/* FIXME: handle copy error */
253 	r = ttm_bo_move_accel_cleanup(bo, (void *)fence, NULL,
254 				      evict, no_wait, new_mem);
255 	radeon_fence_unref(&fence);
256 	return r;
257 }
258 
259 static int radeon_move_vram_ram(struct ttm_buffer_object *bo,
260 				bool evict, bool interruptible, bool no_wait,
261 				struct ttm_mem_reg *new_mem)
262 {
263 	struct radeon_device *rdev;
264 	struct ttm_mem_reg *old_mem = &bo->mem;
265 	struct ttm_mem_reg tmp_mem;
266 	uint32_t proposed_placement;
267 	int r;
268 
269 	rdev = radeon_get_rdev(bo->bdev);
270 	tmp_mem = *new_mem;
271 	tmp_mem.mm_node = NULL;
272 	proposed_placement = TTM_PL_FLAG_TT | TTM_PL_MASK_CACHING;
273 	r = ttm_bo_mem_space(bo, proposed_placement, &tmp_mem,
274 			     interruptible, no_wait);
275 	if (unlikely(r)) {
276 		return r;
277 	}
278 	r = ttm_tt_bind(bo->ttm, &tmp_mem);
279 	if (unlikely(r)) {
280 		goto out_cleanup;
281 	}
282 	r = radeon_move_blit(bo, true, no_wait, &tmp_mem, old_mem);
283 	if (unlikely(r)) {
284 		goto out_cleanup;
285 	}
286 	r = ttm_bo_move_ttm(bo, true, no_wait, new_mem);
287 out_cleanup:
288 	if (tmp_mem.mm_node) {
289 		spin_lock(&rdev->mman.bdev.lru_lock);
290 		drm_mm_put_block(tmp_mem.mm_node);
291 		spin_unlock(&rdev->mman.bdev.lru_lock);
292 		return r;
293 	}
294 	return r;
295 }
296 
297 static int radeon_move_ram_vram(struct ttm_buffer_object *bo,
298 				bool evict, bool interruptible, bool no_wait,
299 				struct ttm_mem_reg *new_mem)
300 {
301 	struct radeon_device *rdev;
302 	struct ttm_mem_reg *old_mem = &bo->mem;
303 	struct ttm_mem_reg tmp_mem;
304 	uint32_t proposed_flags;
305 	int r;
306 
307 	rdev = radeon_get_rdev(bo->bdev);
308 	tmp_mem = *new_mem;
309 	tmp_mem.mm_node = NULL;
310 	proposed_flags = TTM_PL_FLAG_TT | TTM_PL_MASK_CACHING;
311 	r = ttm_bo_mem_space(bo, proposed_flags, &tmp_mem,
312 			     interruptible, no_wait);
313 	if (unlikely(r)) {
314 		return r;
315 	}
316 	r = ttm_bo_move_ttm(bo, true, no_wait, &tmp_mem);
317 	if (unlikely(r)) {
318 		goto out_cleanup;
319 	}
320 	r = radeon_move_blit(bo, true, no_wait, new_mem, old_mem);
321 	if (unlikely(r)) {
322 		goto out_cleanup;
323 	}
324 out_cleanup:
325 	if (tmp_mem.mm_node) {
326 		spin_lock(&rdev->mman.bdev.lru_lock);
327 		drm_mm_put_block(tmp_mem.mm_node);
328 		spin_unlock(&rdev->mman.bdev.lru_lock);
329 		return r;
330 	}
331 	return r;
332 }
333 
334 static int radeon_bo_move(struct ttm_buffer_object *bo,
335 			  bool evict, bool interruptible, bool no_wait,
336 			  struct ttm_mem_reg *new_mem)
337 {
338 	struct radeon_device *rdev;
339 	struct ttm_mem_reg *old_mem = &bo->mem;
340 	int r;
341 
342 	rdev = radeon_get_rdev(bo->bdev);
343 	if (old_mem->mem_type == TTM_PL_SYSTEM && bo->ttm == NULL) {
344 		radeon_move_null(bo, new_mem);
345 		return 0;
346 	}
347 	if ((old_mem->mem_type == TTM_PL_TT &&
348 	     new_mem->mem_type == TTM_PL_SYSTEM) ||
349 	    (old_mem->mem_type == TTM_PL_SYSTEM &&
350 	     new_mem->mem_type == TTM_PL_TT)) {
351 		/* bind is enought */
352 		radeon_move_null(bo, new_mem);
353 		return 0;
354 	}
355 	if (!rdev->cp.ready) {
356 		/* use memcpy */
357 		DRM_ERROR("CP is not ready use memcpy.\n");
358 		goto memcpy;
359 	}
360 
361 	if (old_mem->mem_type == TTM_PL_VRAM &&
362 	    new_mem->mem_type == TTM_PL_SYSTEM) {
363 		r = radeon_move_vram_ram(bo, evict, interruptible,
364 					    no_wait, new_mem);
365 	} else if (old_mem->mem_type == TTM_PL_SYSTEM &&
366 		   new_mem->mem_type == TTM_PL_VRAM) {
367 		r = radeon_move_ram_vram(bo, evict, interruptible,
368 					    no_wait, new_mem);
369 	} else {
370 		r = radeon_move_blit(bo, evict, no_wait, new_mem, old_mem);
371 	}
372 
373 	if (r) {
374 memcpy:
375 		r = ttm_bo_move_memcpy(bo, evict, no_wait, new_mem);
376 	}
377 
378 	return r;
379 }
380 
381 const uint32_t radeon_mem_prios[] = {
382 	TTM_PL_VRAM,
383 	TTM_PL_TT,
384 	TTM_PL_SYSTEM,
385 };
386 
387 const uint32_t radeon_busy_prios[] = {
388 	TTM_PL_TT,
389 	TTM_PL_VRAM,
390 	TTM_PL_SYSTEM,
391 };
392 
393 static int radeon_sync_obj_wait(void *sync_obj, void *sync_arg,
394 				bool lazy, bool interruptible)
395 {
396 	return radeon_fence_wait((struct radeon_fence *)sync_obj, interruptible);
397 }
398 
399 static int radeon_sync_obj_flush(void *sync_obj, void *sync_arg)
400 {
401 	return 0;
402 }
403 
404 static void radeon_sync_obj_unref(void **sync_obj)
405 {
406 	radeon_fence_unref((struct radeon_fence **)sync_obj);
407 }
408 
409 static void *radeon_sync_obj_ref(void *sync_obj)
410 {
411 	return radeon_fence_ref((struct radeon_fence *)sync_obj);
412 }
413 
414 static bool radeon_sync_obj_signaled(void *sync_obj, void *sync_arg)
415 {
416 	return radeon_fence_signaled((struct radeon_fence *)sync_obj);
417 }
418 
419 static struct ttm_bo_driver radeon_bo_driver = {
420 	.mem_type_prio = radeon_mem_prios,
421 	.mem_busy_prio = radeon_busy_prios,
422 	.num_mem_type_prio = ARRAY_SIZE(radeon_mem_prios),
423 	.num_mem_busy_prio = ARRAY_SIZE(radeon_busy_prios),
424 	.create_ttm_backend_entry = &radeon_create_ttm_backend_entry,
425 	.invalidate_caches = &radeon_invalidate_caches,
426 	.init_mem_type = &radeon_init_mem_type,
427 	.evict_flags = &radeon_evict_flags,
428 	.move = &radeon_bo_move,
429 	.verify_access = &radeon_verify_access,
430 	.sync_obj_signaled = &radeon_sync_obj_signaled,
431 	.sync_obj_wait = &radeon_sync_obj_wait,
432 	.sync_obj_flush = &radeon_sync_obj_flush,
433 	.sync_obj_unref = &radeon_sync_obj_unref,
434 	.sync_obj_ref = &radeon_sync_obj_ref,
435 	.move_notify = &radeon_bo_move_notify,
436 	.fault_reserve_notify = &radeon_bo_fault_reserve_notify,
437 };
438 
439 int radeon_ttm_init(struct radeon_device *rdev)
440 {
441 	int r;
442 
443 	r = radeon_ttm_global_init(rdev);
444 	if (r) {
445 		return r;
446 	}
447 	/* No others user of address space so set it to 0 */
448 	r = ttm_bo_device_init(&rdev->mman.bdev,
449 			       rdev->mman.mem_global_ref.object,
450 			       &radeon_bo_driver, DRM_FILE_PAGE_OFFSET,
451 			       rdev->need_dma32);
452 	if (r) {
453 		DRM_ERROR("failed initializing buffer object driver(%d).\n", r);
454 		return r;
455 	}
456 	r = ttm_bo_init_mm(&rdev->mman.bdev, TTM_PL_VRAM, 0,
457 			   ((rdev->mc.real_vram_size) >> PAGE_SHIFT));
458 	if (r) {
459 		DRM_ERROR("Failed initializing VRAM heap.\n");
460 		return r;
461 	}
462 	r = radeon_object_create(rdev, NULL, 256 * 1024, true,
463 				 RADEON_GEM_DOMAIN_VRAM, false,
464 				 &rdev->stollen_vga_memory);
465 	if (r) {
466 		return r;
467 	}
468 	r = radeon_object_pin(rdev->stollen_vga_memory, RADEON_GEM_DOMAIN_VRAM, NULL);
469 	if (r) {
470 		radeon_object_unref(&rdev->stollen_vga_memory);
471 		return r;
472 	}
473 	DRM_INFO("radeon: %uM of VRAM memory ready\n",
474 		 rdev->mc.real_vram_size / (1024 * 1024));
475 	r = ttm_bo_init_mm(&rdev->mman.bdev, TTM_PL_TT, 0,
476 			   ((rdev->mc.gtt_size) >> PAGE_SHIFT));
477 	if (r) {
478 		DRM_ERROR("Failed initializing GTT heap.\n");
479 		return r;
480 	}
481 	DRM_INFO("radeon: %uM of GTT memory ready.\n",
482 		 rdev->mc.gtt_size / (1024 * 1024));
483 	if (unlikely(rdev->mman.bdev.dev_mapping == NULL)) {
484 		rdev->mman.bdev.dev_mapping = rdev->ddev->dev_mapping;
485 	}
486 	return 0;
487 }
488 
489 void radeon_ttm_fini(struct radeon_device *rdev)
490 {
491 	if (rdev->stollen_vga_memory) {
492 		radeon_object_unpin(rdev->stollen_vga_memory);
493 		radeon_object_unref(&rdev->stollen_vga_memory);
494 	}
495 	ttm_bo_clean_mm(&rdev->mman.bdev, TTM_PL_VRAM);
496 	ttm_bo_clean_mm(&rdev->mman.bdev, TTM_PL_TT);
497 	ttm_bo_device_release(&rdev->mman.bdev);
498 	radeon_gart_fini(rdev);
499 	radeon_ttm_global_fini(rdev);
500 	DRM_INFO("radeon: ttm finalized\n");
501 }
502 
503 static struct vm_operations_struct radeon_ttm_vm_ops;
504 static struct vm_operations_struct *ttm_vm_ops = NULL;
505 
506 static int radeon_ttm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
507 {
508 	struct ttm_buffer_object *bo;
509 	int r;
510 
511 	bo = (struct ttm_buffer_object *)vma->vm_private_data;
512 	if (bo == NULL) {
513 		return VM_FAULT_NOPAGE;
514 	}
515 	r = ttm_vm_ops->fault(vma, vmf);
516 	return r;
517 }
518 
519 int radeon_mmap(struct file *filp, struct vm_area_struct *vma)
520 {
521 	struct drm_file *file_priv;
522 	struct radeon_device *rdev;
523 	int r;
524 
525 	if (unlikely(vma->vm_pgoff < DRM_FILE_PAGE_OFFSET)) {
526 		return drm_mmap(filp, vma);
527 	}
528 
529 	file_priv = (struct drm_file *)filp->private_data;
530 	rdev = file_priv->minor->dev->dev_private;
531 	if (rdev == NULL) {
532 		return -EINVAL;
533 	}
534 	r = ttm_bo_mmap(filp, vma, &rdev->mman.bdev);
535 	if (unlikely(r != 0)) {
536 		return r;
537 	}
538 	if (unlikely(ttm_vm_ops == NULL)) {
539 		ttm_vm_ops = vma->vm_ops;
540 		radeon_ttm_vm_ops = *ttm_vm_ops;
541 		radeon_ttm_vm_ops.fault = &radeon_ttm_fault;
542 	}
543 	vma->vm_ops = &radeon_ttm_vm_ops;
544 	return 0;
545 }
546 
547 
548 /*
549  * TTM backend functions.
550  */
551 struct radeon_ttm_backend {
552 	struct ttm_backend		backend;
553 	struct radeon_device		*rdev;
554 	unsigned long			num_pages;
555 	struct page			**pages;
556 	struct page			*dummy_read_page;
557 	bool				populated;
558 	bool				bound;
559 	unsigned			offset;
560 };
561 
562 static int radeon_ttm_backend_populate(struct ttm_backend *backend,
563 				       unsigned long num_pages,
564 				       struct page **pages,
565 				       struct page *dummy_read_page)
566 {
567 	struct radeon_ttm_backend *gtt;
568 
569 	gtt = container_of(backend, struct radeon_ttm_backend, backend);
570 	gtt->pages = pages;
571 	gtt->num_pages = num_pages;
572 	gtt->dummy_read_page = dummy_read_page;
573 	gtt->populated = true;
574 	return 0;
575 }
576 
577 static void radeon_ttm_backend_clear(struct ttm_backend *backend)
578 {
579 	struct radeon_ttm_backend *gtt;
580 
581 	gtt = container_of(backend, struct radeon_ttm_backend, backend);
582 	gtt->pages = NULL;
583 	gtt->num_pages = 0;
584 	gtt->dummy_read_page = NULL;
585 	gtt->populated = false;
586 	gtt->bound = false;
587 }
588 
589 
590 static int radeon_ttm_backend_bind(struct ttm_backend *backend,
591 				   struct ttm_mem_reg *bo_mem)
592 {
593 	struct radeon_ttm_backend *gtt;
594 	int r;
595 
596 	gtt = container_of(backend, struct radeon_ttm_backend, backend);
597 	gtt->offset = bo_mem->mm_node->start << PAGE_SHIFT;
598 	if (!gtt->num_pages) {
599 		WARN(1, "nothing to bind %lu pages for mreg %p back %p!\n", gtt->num_pages, bo_mem, backend);
600 	}
601 	r = radeon_gart_bind(gtt->rdev, gtt->offset,
602 			     gtt->num_pages, gtt->pages);
603 	if (r) {
604 		DRM_ERROR("failed to bind %lu pages at 0x%08X\n",
605 			  gtt->num_pages, gtt->offset);
606 		return r;
607 	}
608 	gtt->bound = true;
609 	return 0;
610 }
611 
612 static int radeon_ttm_backend_unbind(struct ttm_backend *backend)
613 {
614 	struct radeon_ttm_backend *gtt;
615 
616 	gtt = container_of(backend, struct radeon_ttm_backend, backend);
617 	radeon_gart_unbind(gtt->rdev, gtt->offset, gtt->num_pages);
618 	gtt->bound = false;
619 	return 0;
620 }
621 
622 static void radeon_ttm_backend_destroy(struct ttm_backend *backend)
623 {
624 	struct radeon_ttm_backend *gtt;
625 
626 	gtt = container_of(backend, struct radeon_ttm_backend, backend);
627 	if (gtt->bound) {
628 		radeon_ttm_backend_unbind(backend);
629 	}
630 	kfree(gtt);
631 }
632 
633 static struct ttm_backend_func radeon_backend_func = {
634 	.populate = &radeon_ttm_backend_populate,
635 	.clear = &radeon_ttm_backend_clear,
636 	.bind = &radeon_ttm_backend_bind,
637 	.unbind = &radeon_ttm_backend_unbind,
638 	.destroy = &radeon_ttm_backend_destroy,
639 };
640 
641 struct ttm_backend *radeon_ttm_backend_create(struct radeon_device *rdev)
642 {
643 	struct radeon_ttm_backend *gtt;
644 
645 	gtt = kzalloc(sizeof(struct radeon_ttm_backend), GFP_KERNEL);
646 	if (gtt == NULL) {
647 		return NULL;
648 	}
649 	gtt->backend.bdev = &rdev->mman.bdev;
650 	gtt->backend.flags = 0;
651 	gtt->backend.func = &radeon_backend_func;
652 	gtt->rdev = rdev;
653 	gtt->pages = NULL;
654 	gtt->num_pages = 0;
655 	gtt->dummy_read_page = NULL;
656 	gtt->populated = false;
657 	gtt->bound = false;
658 	return &gtt->backend;
659 }
660