summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/vmwgfx/vmwgfx_mob.c
blob: c5897cb4e4d51d9e3803e36905e5dc0fdbac1657 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
/**************************************************************************
 *
 * Copyright © 2012 VMware, Inc., Palo Alto, CA., USA
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 **************************************************************************/

#include "vmwgfx_drv.h"

/*
 * If we set up the screen target otable, screen objects stop working.
 */

#define VMW_OTABLE_SETUP_SUB ((VMWGFX_ENABLE_SCREEN_TARGET_OTABLE ? 0 : 1))

#ifdef CONFIG_64BIT
#define VMW_PPN_SIZE 8
#define VMW_MOBFMT_PTDEPTH_0 SVGA3D_MOBFMT_PTDEPTH64_0
#define VMW_MOBFMT_PTDEPTH_1 SVGA3D_MOBFMT_PTDEPTH64_1
#define VMW_MOBFMT_PTDEPTH_2 SVGA3D_MOBFMT_PTDEPTH64_2
#else
#define VMW_PPN_SIZE 4
#define VMW_MOBFMT_PTDEPTH_0 SVGA3D_MOBFMT_PTDEPTH_0
#define VMW_MOBFMT_PTDEPTH_1 SVGA3D_MOBFMT_PTDEPTH_1
#define VMW_MOBFMT_PTDEPTH_2 SVGA3D_MOBFMT_PTDEPTH_2
#endif

/*
 * struct vmw_mob - Structure containing page table and metadata for a
 * Guest Memory OBject.
 *
 * @num_pages       Number of pages that make up the page table.
 * @pt_level        The indirection level of the page table. 0-2.
 * @pt_root_page    DMA address of the level 0 page of the page table.
 */
struct vmw_mob {
	struct ttm_buffer_object *pt_bo;
	unsigned long num_pages;
	unsigned pt_level;
	dma_addr_t pt_root_page;
	uint32_t id;
};

/*
 * struct vmw_otable - Guest Memory OBject table metadata
 *
 * @size:           Size of the table (page-aligned).
 * @page_table:     Pointer to a struct vmw_mob holding the page table.
 */
struct vmw_otable {
	unsigned long size;
	struct vmw_mob *page_table;
};

static int vmw_mob_pt_populate(struct vmw_private *dev_priv,
			       struct vmw_mob *mob);
static void vmw_mob_pt_setup(struct vmw_mob *mob,
			     struct vmw_piter data_iter,
			     unsigned long num_data_pages);

/*
 * vmw_setup_otable_base - Issue an object table base setup command to
 * the device
 *
 * @dev_priv:       Pointer to a device private structure
 * @type:           Type of object table base
 * @offset          Start of table offset into dev_priv::otable_bo
 * @otable          Pointer to otable metadata;
 *
 * This function returns -ENOMEM if it fails to reserve fifo space,
 * and may block waiting for fifo space.
 */
static int vmw_setup_otable_base(struct vmw_private *dev_priv,
				 SVGAOTableType type,
				 unsigned long offset,
				 struct vmw_otable *otable)
{
	struct {
		SVGA3dCmdHeader header;
		SVGA3dCmdSetOTableBase64 body;
	} *cmd;
	struct vmw_mob *mob;
	const struct vmw_sg_table *vsgt;
	struct vmw_piter iter;
	int ret;

	BUG_ON(otable->page_table != NULL);

	vsgt = vmw_bo_sg_table(dev_priv->otable_bo);
	vmw_piter_start(&iter, vsgt, offset >> PAGE_SHIFT);
	WARN_ON(!vmw_piter_next(&iter));

	mob = vmw_mob_create(otable->size >> PAGE_SHIFT);
	if (unlikely(mob == NULL)) {
		DRM_ERROR("Failed creating OTable page table.\n");
		return -ENOMEM;
	}

	if (otable->size <= PAGE_SIZE) {
		mob->pt_level = VMW_MOBFMT_PTDEPTH_0;
		mob->pt_root_page = vmw_piter_dma_addr(&iter);
	} else if (vsgt->num_regions == 1) {
		mob->pt_level = SVGA3D_MOBFMT_RANGE;
		mob->pt_root_page = vmw_piter_dma_addr(&iter);
	} else {
		ret = vmw_mob_pt_populate(dev_priv, mob);
		if (unlikely(ret != 0))
			goto out_no_populate;

		vmw_mob_pt_setup(mob, iter, otable->size >> PAGE_SHIFT);
		mob->pt_level += VMW_MOBFMT_PTDEPTH_1 - SVGA3D_MOBFMT_PTDEPTH_1;
	}

	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
	if (unlikely(cmd == NULL)) {
		DRM_ERROR("Failed reserving FIFO space for OTable setup.\n");
		ret = -ENOMEM;
		goto out_no_fifo;
	}

	memset(cmd, 0, sizeof(*cmd));
	cmd->header.id = SVGA_3D_CMD_SET_OTABLE_BASE64;
	cmd->header.size = sizeof(cmd->body);
	cmd->body.type = type;
	cmd->body.baseAddress = mob->pt_root_page >> PAGE_SHIFT;
	cmd->body.sizeInBytes = otable->size;
	cmd->body.validSizeInBytes = 0;
	cmd->body.ptDepth = mob->pt_level;

	/*
	 * The device doesn't support this, But the otable size is
	 * determined at compile-time, so this BUG shouldn't trigger
	 * randomly.
	 */
	BUG_ON(mob->pt_level == VMW_MOBFMT_PTDEPTH_2);

	vmw_fifo_commit(dev_priv, sizeof(*cmd));
	otable->page_table = mob;

	return 0;

out_no_fifo:
out_no_populate:
	vmw_mob_destroy(mob);
	return ret;
}

/*
 * vmw_takedown_otable_base - Issue an object table base takedown command
 * to the device
 *
 * @dev_priv:       Pointer to a device private structure
 * @type:           Type of object table base
 *
 */
static void vmw_takedown_otable_base(struct vmw_private *dev_priv,
				     SVGAOTableType type,
				     struct vmw_otable *otable)
{
	struct {
		SVGA3dCmdHeader header;
		SVGA3dCmdSetOTableBase body;
	} *cmd;
	struct ttm_buffer_object *bo;

	if (otable->page_table == NULL)
		return;

	bo = otable->page_table->pt_bo;
	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
	if (unlikely(cmd == NULL)) {
		DRM_ERROR("Failed reserving FIFO space for OTable "
			  "takedown.\n");
		return;
	}
 
	memset(cmd, 0, sizeof(*cmd));
	cmd->header.id = SVGA_3D_CMD_SET_OTABLE_BASE;
	cmd->header.size = sizeof(cmd->body);
	cmd->body.type = type;
	cmd->body.baseAddress = 0;
	cmd->body.sizeInBytes = 0;
	cmd->body.validSizeInBytes = 0;
	cmd->body.ptDepth = SVGA3D_MOBFMT_INVALID;
	vmw_fifo_commit(dev_priv, sizeof(*cmd));

	if (bo) {
		int ret;

		ret = ttm_bo_reserve(bo, false, true, false, NULL);
		BUG_ON(ret != 0);

		vmw_fence_single_bo(bo, NULL);
		ttm_bo_unreserve(bo);
	}

	vmw_mob_destroy(otable->page_table);
	otable->page_table = NULL;
}

/*
 * vmw_otables_setup - Set up guest backed memory object tables
 *
 * @dev_priv:       Pointer to a device private structure
 *
 * Takes care of the device guest backed surface
 * initialization, by setting up the guest backed memory object tables.
 * Returns 0 on success and various error codes on failure. A succesful return
 * means the object tables can be taken down using the vmw_otables_takedown
 * function.
 */
int vmw_otables_setup(struct vmw_private *dev_priv)
{
	unsigned long offset;
	unsigned long bo_size;
	struct vmw_otable *otables;
	SVGAOTableType i;
	int ret;

	otables = kzalloc(SVGA_OTABLE_DX9_MAX * sizeof(*otables),
			  GFP_KERNEL);
	if (unlikely(otables == NULL)) {
		DRM_ERROR("Failed to allocate space for otable "
			  "metadata.\n");
		return -ENOMEM;
	}

	otables[SVGA_OTABLE_MOB].size =
		VMWGFX_NUM_MOB * SVGA3D_OTABLE_MOB_ENTRY_SIZE;
	otables[SVGA_OTABLE_SURFACE].size =
		VMWGFX_NUM_GB_SURFACE * SVGA3D_OTABLE_SURFACE_ENTRY_SIZE;
	otables[SVGA_OTABLE_CONTEXT].size =
		VMWGFX_NUM_GB_CONTEXT * SVGA3D_OTABLE_CONTEXT_ENTRY_SIZE;
	otables[SVGA_OTABLE_SHADER].size =
		VMWGFX_NUM_GB_SHADER * SVGA3D_OTABLE_SHADER_ENTRY_SIZE;
	otables[SVGA_OTABLE_SCREEN_TARGET].size =
		VMWGFX_NUM_GB_SCREEN_TARGET *
		SVGA3D_OTABLE_SCREEN_TARGET_ENTRY_SIZE;

	bo_size = 0;
	for (i = 0; i < SVGA_OTABLE_DX9_MAX; ++i) {
		otables[i].size =
			(otables[i].size + PAGE_SIZE - 1) & PAGE_MASK;
		bo_size += otables[i].size;
	}

	ret = ttm_bo_create(&dev_priv->bdev, bo_size,
			    ttm_bo_type_device,
			    &vmw_sys_ne_placement,
			    0, false, NULL,
			    &dev_priv->otable_bo);

	if (unlikely(ret != 0))
		goto out_no_bo;

	ret = ttm_bo_reserve(dev_priv->otable_bo, false, true, false, NULL);
	BUG_ON(ret != 0);
	ret = vmw_bo_driver.ttm_tt_populate(dev_priv->otable_bo->ttm);
	if (unlikely(ret != 0))
		goto out_unreserve;
	ret = vmw_bo_map_dma(dev_priv->otable_bo);
	if (unlikely(ret != 0))
		goto out_unreserve;

	ttm_bo_unreserve(dev_priv->otable_bo);

	offset = 0;
	for (i = 0; i < SVGA_OTABLE_DX9_MAX - VMW_OTABLE_SETUP_SUB; ++i) {
		ret = vmw_setup_otable_base(dev_priv, i, offset,
					    &otables[i]);
		if (unlikely(ret != 0))
			goto out_no_setup;
		offset += otables[i].size;
	}

	dev_priv->otables = otables;
	return 0;

out_unreserve:
	ttm_bo_unreserve(dev_priv->otable_bo);
out_no_setup:
	for (i = 0; i < SVGA_OTABLE_DX9_MAX - VMW_OTABLE_SETUP_SUB; ++i)
		vmw_takedown_otable_base(dev_priv, i, &otables[i]);

	ttm_bo_unref(&dev_priv->otable_bo);
out_no_bo:
	kfree(otables);
	return ret;
}


/*
 * vmw_otables_takedown - Take down guest backed memory object tables
 *
 * @dev_priv:       Pointer to a device private structure
 *
 * Take down the Guest Memory Object tables.
 */
void vmw_otables_takedown(struct vmw_private *dev_priv)
{
	SVGAOTableType i;
	struct ttm_buffer_object *bo = dev_priv->otable_bo;
	int ret;

	for (i = 0; i < SVGA_OTABLE_DX9_MAX - VMW_OTABLE_SETUP_SUB; ++i)
		vmw_takedown_otable_base(dev_priv, i,
					 &dev_priv->otables[i]);

	ret = ttm_bo_reserve(bo, false, true, false, NULL);
	BUG_ON(ret != 0);

	vmw_fence_single_bo(bo, NULL);
	ttm_bo_unreserve(bo);

	ttm_bo_unref(&dev_priv->otable_bo);
	kfree(dev_priv->otables);
	dev_priv->otables = NULL;
}


/*
 * vmw_mob_calculate_pt_pages - Calculate the number of page table pages
 * needed for a guest backed memory object.
 *
 * @data_pages:  Number of data pages in the memory object buffer.
 */
static unsigned long vmw_mob_calculate_pt_pages(unsigned long data_pages)
{
	unsigned long data_size = data_pages * PAGE_SIZE;
	unsigned long tot_size = 0;

	while (likely(data_size > PAGE_SIZE)) {
		data_size = DIV_ROUND_UP(data_size, PAGE_SIZE);
		data_size *= VMW_PPN_SIZE;
		tot_size += (data_size + PAGE_SIZE - 1) & PAGE_MASK;
	}

	return tot_size >> PAGE_SHIFT;
}

/*
 * vmw_mob_create - Create a mob, but don't populate it.
 *
 * @data_pages:  Number of data pages of the underlying buffer object.
 */
struct vmw_mob *vmw_mob_create(unsigned long data_pages)
{
	struct vmw_mob *mob = kzalloc(sizeof(*mob), GFP_KERNEL);

	if (unlikely(mob == NULL))
		return NULL;

	mob->num_pages = vmw_mob_calculate_pt_pages(data_pages);

	return mob;
}

/*
 * vmw_mob_pt_populate - Populate the mob pagetable
 *
 * @mob:         Pointer to the mob the pagetable of which we want to
 *               populate.
 *
 * This function allocates memory to be used for the pagetable, and
 * adjusts TTM memory accounting accordingly. Returns ENOMEM if
 * memory resources aren't sufficient and may cause TTM buffer objects
 * to be swapped out by using the TTM memory accounting function.
 */
static int vmw_mob_pt_populate(struct vmw_private *dev_priv,
			       struct vmw_mob *mob)
{
	int ret;
	BUG_ON(mob->pt_bo != NULL);

	ret = ttm_bo_create(&dev_priv->bdev, mob->num_pages * PAGE_SIZE,
			    ttm_bo_type_device,
			    &vmw_sys_ne_placement,
			    0, false, NULL, &mob->pt_bo);
	if (unlikely(ret != 0))
		return ret;

	ret = ttm_bo_reserve(mob->pt_bo, false, true, false, NULL);

	BUG_ON(ret != 0);
	ret = vmw_bo_driver.ttm_tt_populate(mob->pt_bo->ttm);
	if (unlikely(ret != 0))
		goto out_unreserve;
	ret = vmw_bo_map_dma(mob->pt_bo);
	if (unlikely(ret != 0))
		goto out_unreserve;

	ttm_bo_unreserve(mob->pt_bo);
	
	return 0;

out_unreserve:
	ttm_bo_unreserve(mob->pt_bo);
	ttm_bo_unref(&mob->pt_bo);

	return ret;
}

/**
 * vmw_mob_assign_ppn - Assign a value to a page table entry
 *
 * @addr: Pointer to pointer to page table entry.
 * @val: The page table entry
 *
 * Assigns a value to a page table entry pointed to by *@addr and increments
 * *@addr according to the page table entry size.
 */
#if (VMW_PPN_SIZE == 8)
static void vmw_mob_assign_ppn(u32 **addr, dma_addr_t val)
{
	*((u64 *) *addr) = val >> PAGE_SHIFT;
	*addr += 2;
}
#else
static void vmw_mob_assign_ppn(u32 **addr, dma_addr_t val)
{
	*(*addr)++ = val >> PAGE_SHIFT;
}
#endif

/*
 * vmw_mob_build_pt - Build a pagetable
 *
 * @data_addr:      Array of DMA addresses to the underlying buffer
 *                  object's data pages.
 * @num_data_pages: Number of buffer object data pages.
 * @pt_pages:       Array of page pointers to the page table pages.
 *
 * Returns the number of page table pages actually used.
 * Uses atomic kmaps of highmem pages to avoid TLB thrashing.
 */
static unsigned long vmw_mob_build_pt(struct vmw_piter *data_iter,
				      unsigned long num_data_pages,
				      struct vmw_piter *pt_iter)
{
	unsigned long pt_size = num_data_pages * VMW_PPN_SIZE;
	unsigned long num_pt_pages = DIV_ROUND_UP(pt_size, PAGE_SIZE);
	unsigned long pt_page;
	u32 *addr, *save_addr;
	unsigned long i;
	struct page *page;

	for (pt_page = 0; pt_page < num_pt_pages; ++pt_page) {
		page = vmw_piter_page(pt_iter);

		save_addr = addr = kmap_atomic(page);

		for (i = 0; i < PAGE_SIZE / VMW_PPN_SIZE; ++i) {
			vmw_mob_assign_ppn(&addr,
					   vmw_piter_dma_addr(data_iter));
			if (unlikely(--num_data_pages == 0))
				break;
			WARN_ON(!vmw_piter_next(data_iter));
		}
		kunmap_atomic(save_addr);
		vmw_piter_next(pt_iter);
	}

	return num_pt_pages;
}

/*
 * vmw_mob_build_pt - Set up a multilevel mob pagetable
 *
 * @mob:            Pointer to a mob whose page table needs setting up.
 * @data_addr       Array of DMA addresses to the buffer object's data
 *                  pages.
 * @num_data_pages: Number of buffer object data pages.
 *
 * Uses tail recursion to set up a multilevel mob page table.
 */
static void vmw_mob_pt_setup(struct vmw_mob *mob,
			     struct vmw_piter data_iter,
			     unsigned long num_data_pages)
{
	unsigned long num_pt_pages = 0;
	struct ttm_buffer_object *bo = mob->pt_bo;
	struct vmw_piter save_pt_iter;
	struct vmw_piter pt_iter;
	const struct vmw_sg_table *vsgt;
	int ret;

	ret = ttm_bo_reserve(bo, false, true, false, NULL);
	BUG_ON(ret != 0);

	vsgt = vmw_bo_sg_table(bo);
	vmw_piter_start(&pt_iter, vsgt, 0);
	BUG_ON(!vmw_piter_next(&pt_iter));
	mob->pt_level = 0;
	while (likely(num_data_pages > 1)) {
		++mob->pt_level;
		BUG_ON(mob->pt_level > 2);
		save_pt_iter = pt_iter;
		num_pt_pages = vmw_mob_build_pt(&data_iter, num_data_pages,
						&pt_iter);
		data_iter = save_pt_iter;
		num_data_pages = num_pt_pages;
	}

	mob->pt_root_page = vmw_piter_dma_addr(&save_pt_iter);
	ttm_bo_unreserve(bo);
}

/*
 * vmw_mob_destroy - Destroy a mob, unpopulating first if necessary.
 *
 * @mob:            Pointer to a mob to destroy.
 */
void vmw_mob_destroy(struct vmw_mob *mob)
{
	if (mob->pt_bo)
		ttm_bo_unref(&mob->pt_bo);
	kfree(mob);
}

/*
 * vmw_mob_unbind - Hide a mob from the device.
 *
 * @dev_priv:       Pointer to a device private.
 * @mob_id:         Device id of the mob to unbind.
 */
void vmw_mob_unbind(struct vmw_private *dev_priv,
		    struct vmw_mob *mob)
{
	struct {
		SVGA3dCmdHeader header;
		SVGA3dCmdDestroyGBMob body;
	} *cmd;
	int ret;
	struct ttm_buffer_object *bo = mob->pt_bo;

	if (bo) {
		ret = ttm_bo_reserve(bo, false, true, false, NULL);
		/*
		 * Noone else should be using this buffer.
		 */
		BUG_ON(ret != 0);
	}

	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
	if (unlikely(cmd == NULL)) {
		DRM_ERROR("Failed reserving FIFO space for Memory "
			  "Object unbinding.\n");
	} else {
		cmd->header.id = SVGA_3D_CMD_DESTROY_GB_MOB;
		cmd->header.size = sizeof(cmd->body);
		cmd->body.mobid = mob->id;
		vmw_fifo_commit(dev_priv, sizeof(*cmd));
	}
	if (bo) {
		vmw_fence_single_bo(bo, NULL);
		ttm_bo_unreserve(bo);
	}
	vmw_fifo_resource_dec(dev_priv);
}

/*
 * vmw_mob_bind - Make a mob visible to the device after first
 *                populating it if necessary.
 *
 * @dev_priv:       Pointer to a device private.
 * @mob:            Pointer to the mob we're making visible.
 * @data_addr:      Array of DMA addresses to the data pages of the underlying
 *                  buffer object.
 * @num_data_pages: Number of data pages of the underlying buffer
 *                  object.
 * @mob_id:         Device id of the mob to bind
 *
 * This function is intended to be interfaced with the ttm_tt backend
 * code.
 */
int vmw_mob_bind(struct vmw_private *dev_priv,
		 struct vmw_mob *mob,
		 const struct vmw_sg_table *vsgt,
		 unsigned long num_data_pages,
		 int32_t mob_id)
{
	int ret;
	bool pt_set_up = false;
	struct vmw_piter data_iter;
	struct {
		SVGA3dCmdHeader header;
		SVGA3dCmdDefineGBMob64 body;
	} *cmd;

	mob->id = mob_id;
	vmw_piter_start(&data_iter, vsgt, 0);
	if (unlikely(!vmw_piter_next(&data_iter)))
		return 0;

	if (likely(num_data_pages == 1)) {
		mob->pt_level = VMW_MOBFMT_PTDEPTH_0;
		mob->pt_root_page = vmw_piter_dma_addr(&data_iter);
	} else if (vsgt->num_regions == 1) {
		mob->pt_level = SVGA3D_MOBFMT_RANGE;
		mob->pt_root_page = vmw_piter_dma_addr(&data_iter);
	} else if (unlikely(mob->pt_bo == NULL)) {
		ret = vmw_mob_pt_populate(dev_priv, mob);
		if (unlikely(ret != 0))
			return ret;

		vmw_mob_pt_setup(mob, data_iter, num_data_pages);
		pt_set_up = true;
		mob->pt_level += VMW_MOBFMT_PTDEPTH_1 - SVGA3D_MOBFMT_PTDEPTH_1;
	}

	vmw_fifo_resource_inc(dev_priv);

	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
	if (unlikely(cmd == NULL)) {
		DRM_ERROR("Failed reserving FIFO space for Memory "
			  "Object binding.\n");
		goto out_no_cmd_space;
	}

	cmd->header.id = SVGA_3D_CMD_DEFINE_GB_MOB64;
	cmd->header.size = sizeof(cmd->body);
	cmd->body.mobid = mob_id;
	cmd->body.ptDepth = mob->pt_level;
	cmd->body.base = mob->pt_root_page >> PAGE_SHIFT;
	cmd->body.sizeInBytes = num_data_pages * PAGE_SIZE;

	vmw_fifo_commit(dev_priv, sizeof(*cmd));

	return 0;

out_no_cmd_space:
	vmw_fifo_resource_dec(dev_priv);
	if (pt_set_up)
		ttm_bo_unref(&mob->pt_bo);

	return -ENOMEM;
}