Free Electrons

Embedded Linux Experts

   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
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
/******************************************************************************
 *
 * COPYRIGHT © 2014-2015 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_kms.h"
#include "device_include/svga3d_surfacedefs.h"
#include <drm/drm_plane_helper.h>

#define vmw_crtc_to_stdu(x) \
	container_of(x, struct vmw_screen_target_display_unit, base.crtc)
#define vmw_encoder_to_stdu(x) \
	container_of(x, struct vmw_screen_target_display_unit, base.encoder)
#define vmw_connector_to_stdu(x) \
	container_of(x, struct vmw_screen_target_display_unit, base.connector)



enum stdu_content_type {
	SAME_AS_DISPLAY = 0,
	SEPARATE_SURFACE,
	SEPARATE_DMA
};

/**
 * struct vmw_stdu_dirty - closure structure for the update functions
 *
 * @base: The base type we derive from. Used by vmw_kms_helper_dirty().
 * @transfer: Transfer direction for DMA command.
 * @left: Left side of bounding box.
 * @right: Right side of bounding box.
 * @top: Top side of bounding box.
 * @bottom: Bottom side of bounding box.
 * @buf: DMA buffer when DMA-ing between buffer and screen targets.
 * @sid: Surface ID when copying between surface and screen targets.
 */
struct vmw_stdu_dirty {
	struct vmw_kms_dirty base;
	SVGA3dTransferType  transfer;
	s32 left, right, top, bottom;
	u32 pitch;
	union {
		struct vmw_dma_buffer *buf;
		u32 sid;
	};
};

/*
 * SVGA commands that are used by this code. Please see the device headers
 * for explanation.
 */
struct vmw_stdu_update {
	SVGA3dCmdHeader header;
	SVGA3dCmdUpdateGBScreenTarget body;
};

struct vmw_stdu_dma {
	SVGA3dCmdHeader     header;
	SVGA3dCmdSurfaceDMA body;
};

struct vmw_stdu_surface_copy {
	SVGA3dCmdHeader      header;
	SVGA3dCmdSurfaceCopy body;
};


/**
 * struct vmw_screen_target_display_unit
 *
 * @base: VMW specific DU structure
 * @display_srf: surface to be displayed.  The dimension of this will always
 *               match the display mode.  If the display mode matches
 *               content_vfbs dimensions, then this is a pointer into the
 *               corresponding field in content_vfbs.  If not, then this
 *               is a separate buffer to which content_vfbs will blit to.
 * @content_fb: holds the rendered content, can be a surface or DMA buffer
 * @content_type:  content_fb type
 * @defined:  true if the current display unit has been initialized
 */
struct vmw_screen_target_display_unit {
	struct vmw_display_unit base;

	struct vmw_surface     *display_srf;
	struct drm_framebuffer *content_fb;

	enum stdu_content_type content_fb_type;

	bool defined;
};



static void vmw_stdu_destroy(struct vmw_screen_target_display_unit *stdu);



/******************************************************************************
 * Screen Target Display Unit helper Functions
 *****************************************************************************/

/**
 * vmw_stdu_pin_display - pins the resource associated with the display surface
 *
 * @stdu: contains the display surface
 *
 * Since the display surface can either be a private surface allocated by us,
 * or it can point to the content surface, we use this function to not pin the
 * same resource twice.
 */
static int vmw_stdu_pin_display(struct vmw_screen_target_display_unit *stdu)
{
	return vmw_resource_pin(&stdu->display_srf->res, false);
}



/**
 * vmw_stdu_unpin_display - unpins the resource associated with display surface
 *
 * @stdu: contains the display surface
 *
 * If the display surface was privatedly allocated by
 * vmw_surface_gb_priv_define() and not registered as a framebuffer, then it
 * won't be automatically cleaned up when all the framebuffers are freed.  As
 * such, we have to explicitly call vmw_resource_unreference() to get it freed.
 */
static void vmw_stdu_unpin_display(struct vmw_screen_target_display_unit *stdu)
{
	if (stdu->display_srf) {
		struct vmw_resource *res = &stdu->display_srf->res;

		vmw_resource_unpin(res);

		if (stdu->content_fb_type != SAME_AS_DISPLAY) {
			vmw_resource_unreference(&res);
			stdu->content_fb_type = SAME_AS_DISPLAY;
		}

		stdu->display_srf = NULL;
	}
}



/******************************************************************************
 * Screen Target Display Unit CRTC Functions
 *****************************************************************************/


/**
 * vmw_stdu_crtc_destroy - cleans up the STDU
 *
 * @crtc: used to get a reference to the containing STDU
 */
static void vmw_stdu_crtc_destroy(struct drm_crtc *crtc)
{
	vmw_stdu_destroy(vmw_crtc_to_stdu(crtc));
}

/**
 * vmw_stdu_define_st - Defines a Screen Target
 *
 * @dev_priv:  VMW DRM device
 * @stdu: display unit to create a Screen Target for
 *
 * Creates a STDU that we can used later.  This function is called whenever the
 * framebuffer size changes.
 *
 * RETURNs:
 * 0 on success, error code on failure
 */
static int vmw_stdu_define_st(struct vmw_private *dev_priv,
			      struct vmw_screen_target_display_unit *stdu)
{
	struct {
		SVGA3dCmdHeader header;
		SVGA3dCmdDefineGBScreenTarget body;
	} *cmd;

	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));

	if (unlikely(cmd == NULL)) {
		DRM_ERROR("Out of FIFO space defining Screen Target\n");
		return -ENOMEM;
	}

	cmd->header.id   = SVGA_3D_CMD_DEFINE_GB_SCREENTARGET;
	cmd->header.size = sizeof(cmd->body);

	cmd->body.stid   = stdu->base.unit;
	cmd->body.width  = stdu->display_srf->base_size.width;
	cmd->body.height = stdu->display_srf->base_size.height;
	cmd->body.flags  = (0 == cmd->body.stid) ? SVGA_STFLAG_PRIMARY : 0;
	cmd->body.dpi    = 0;
	cmd->body.xRoot  = stdu->base.crtc.x;
	cmd->body.yRoot  = stdu->base.crtc.y;

	if (!stdu->base.is_implicit) {
		cmd->body.xRoot  = stdu->base.gui_x;
		cmd->body.yRoot  = stdu->base.gui_y;
	}

	vmw_fifo_commit(dev_priv, sizeof(*cmd));

	stdu->defined = true;

	return 0;
}



/**
 * vmw_stdu_bind_st - Binds a surface to a Screen Target
 *
 * @dev_priv: VMW DRM device
 * @stdu: display unit affected
 * @res: Buffer to bind to the screen target.  Set to NULL to blank screen.
 *
 * Binding a surface to a Screen Target the same as flipping
 */
static int vmw_stdu_bind_st(struct vmw_private *dev_priv,
			    struct vmw_screen_target_display_unit *stdu,
			    struct vmw_resource *res)
{
	SVGA3dSurfaceImageId image;

	struct {
		SVGA3dCmdHeader header;
		SVGA3dCmdBindGBScreenTarget body;
	} *cmd;


	if (!stdu->defined) {
		DRM_ERROR("No screen target defined\n");
		return -EINVAL;
	}

	/* Set up image using information in vfb */
	memset(&image, 0, sizeof(image));
	image.sid = res ? res->id : SVGA3D_INVALID_ID;

	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));

	if (unlikely(cmd == NULL)) {
		DRM_ERROR("Out of FIFO space binding a screen target\n");
		return -ENOMEM;
	}

	cmd->header.id   = SVGA_3D_CMD_BIND_GB_SCREENTARGET;
	cmd->header.size = sizeof(cmd->body);

	cmd->body.stid   = stdu->base.unit;
	cmd->body.image  = image;

	vmw_fifo_commit(dev_priv, sizeof(*cmd));

	return 0;
}

/**
 * vmw_stdu_populate_update - populate an UPDATE_GB_SCREENTARGET command with a
 * bounding box.
 *
 * @cmd: Pointer to command stream.
 * @unit: Screen target unit.
 * @left: Left side of bounding box.
 * @right: Right side of bounding box.
 * @top: Top side of bounding box.
 * @bottom: Bottom side of bounding box.
 */
static void vmw_stdu_populate_update(void *cmd, int unit,
				     s32 left, s32 right, s32 top, s32 bottom)
{
	struct vmw_stdu_update *update = cmd;

	update->header.id   = SVGA_3D_CMD_UPDATE_GB_SCREENTARGET;
	update->header.size = sizeof(update->body);

	update->body.stid   = unit;
	update->body.rect.x = left;
	update->body.rect.y = top;
	update->body.rect.w = right - left;
	update->body.rect.h = bottom - top;
}

/**
 * vmw_stdu_update_st - Full update of a Screen Target
 *
 * @dev_priv: VMW DRM device
 * @stdu: display unit affected
 *
 * This function needs to be called whenever the content of a screen
 * target has changed completely. Typically as a result of a backing
 * surface change.
 *
 * RETURNS:
 * 0 on success, error code on failure
 */
static int vmw_stdu_update_st(struct vmw_private *dev_priv,
			      struct vmw_screen_target_display_unit *stdu)
{
	struct vmw_stdu_update *cmd;
	struct drm_crtc *crtc = &stdu->base.crtc;

	if (!stdu->defined) {
		DRM_ERROR("No screen target defined");
		return -EINVAL;
	}

	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));

	if (unlikely(cmd == NULL)) {
		DRM_ERROR("Out of FIFO space updating a Screen Target\n");
		return -ENOMEM;
	}

	vmw_stdu_populate_update(cmd, stdu->base.unit, 0, crtc->mode.hdisplay,
				 0, crtc->mode.vdisplay);

	vmw_fifo_commit(dev_priv, sizeof(*cmd));

	return 0;
}



/**
 * vmw_stdu_destroy_st - Destroy a Screen Target
 *
 * @dev_priv:  VMW DRM device
 * @stdu: display unit to destroy
 */
static int vmw_stdu_destroy_st(struct vmw_private *dev_priv,
			       struct vmw_screen_target_display_unit *stdu)
{
	int    ret;

	struct {
		SVGA3dCmdHeader header;
		SVGA3dCmdDestroyGBScreenTarget body;
	} *cmd;


	/* Nothing to do if not successfully defined */
	if (unlikely(!stdu->defined))
		return 0;

	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));

	if (unlikely(cmd == NULL)) {
		DRM_ERROR("Out of FIFO space, screen target not destroyed\n");
		return -ENOMEM;
	}

	cmd->header.id   = SVGA_3D_CMD_DESTROY_GB_SCREENTARGET;
	cmd->header.size = sizeof(cmd->body);

	cmd->body.stid   = stdu->base.unit;

	vmw_fifo_commit(dev_priv, sizeof(*cmd));

	/* Force sync */
	ret = vmw_fallback_wait(dev_priv, false, true, 0, false, 3*HZ);
	if (unlikely(ret != 0))
		DRM_ERROR("Failed to sync with HW");

	stdu->defined = false;

	return ret;
}



/**
 * vmw_stdu_crtc_set_config - Sets a mode
 *
 * @set:  mode parameters
 *
 * This function is the device-specific portion of the DRM CRTC mode set.
 * For the SVGA device, we do this by defining a Screen Target, binding a
 * GB Surface to that target, and finally update the screen target.
 *
 * RETURNS:
 * 0 on success, error code otherwise
 */
static int vmw_stdu_crtc_set_config(struct drm_mode_set *set)
{
	struct vmw_private *dev_priv;
	struct vmw_screen_target_display_unit *stdu;
	struct vmw_framebuffer *vfb;
	struct vmw_framebuffer_surface *new_vfbs;
	struct drm_display_mode *mode;
	struct drm_framebuffer  *new_fb;
	struct drm_crtc      *crtc;
	struct drm_encoder   *encoder;
	struct drm_connector *connector;
	int    ret;


	if (!set || !set->crtc)
		return -EINVAL;

	crtc     = set->crtc;
	crtc->x  = set->x;
	crtc->y  = set->y;
	stdu     = vmw_crtc_to_stdu(crtc);
	mode     = set->mode;
	new_fb   = set->fb;
	dev_priv = vmw_priv(crtc->dev);


	if (set->num_connectors > 1) {
		DRM_ERROR("Too many connectors\n");
		return -EINVAL;
	}

	if (set->num_connectors == 1 &&
	    set->connectors[0] != &stdu->base.connector) {
		DRM_ERROR("Connectors don't match %p %p\n",
			set->connectors[0], &stdu->base.connector);
		return -EINVAL;
	}


	/* Since they always map one to one these are safe */
	connector = &stdu->base.connector;
	encoder   = &stdu->base.encoder;


	/*
	 * After this point the CRTC will be considered off unless a new fb
	 * is bound
	 */
	if (stdu->defined) {
		/* Unbind current surface by binding an invalid one */
		ret = vmw_stdu_bind_st(dev_priv, stdu, NULL);
		if (unlikely(ret != 0))
			return ret;

		/* Update Screen Target, display will now be blank */
		if (crtc->primary->fb) {
			vmw_stdu_update_st(dev_priv, stdu);
			if (unlikely(ret != 0))
				return ret;
		}

		crtc->primary->fb  = NULL;
		crtc->enabled      = false;
		encoder->crtc      = NULL;
		connector->encoder = NULL;

		vmw_stdu_unpin_display(stdu);
		stdu->content_fb      = NULL;
		stdu->content_fb_type = SAME_AS_DISPLAY;

		ret = vmw_stdu_destroy_st(dev_priv, stdu);
		/* The hardware is hung, give up */
		if (unlikely(ret != 0))
			return ret;
	}


	/* Any of these conditions means the caller wants CRTC off */
	if (set->num_connectors == 0 || !mode || !new_fb)
		return 0;


	if (set->x + mode->hdisplay > new_fb->width ||
	    set->y + mode->vdisplay > new_fb->height) {
		DRM_ERROR("Set outside of framebuffer\n");
		return -EINVAL;
	}

	stdu->content_fb = new_fb;
	vfb = vmw_framebuffer_to_vfb(stdu->content_fb);

	if (vfb->dmabuf)
		stdu->content_fb_type = SEPARATE_DMA;

	/*
	 * If the requested mode is different than the width and height
	 * of the FB or if the content buffer is a DMA buf, then allocate
	 * a display FB that matches the dimension of the mode
	 */
	if (mode->hdisplay != new_fb->width  ||
	    mode->vdisplay != new_fb->height ||
	    stdu->content_fb_type != SAME_AS_DISPLAY) {
		struct vmw_surface content_srf;
		struct drm_vmw_size display_base_size = {0};
		struct vmw_surface *display_srf;


		display_base_size.width  = mode->hdisplay;
		display_base_size.height = mode->vdisplay;
		display_base_size.depth  = 1;

		/*
		 * If content buffer is a DMA buf, then we have to construct
		 * surface info
		 */
		if (stdu->content_fb_type == SEPARATE_DMA) {

			switch (new_fb->bits_per_pixel) {
			case 32:
				content_srf.format = SVGA3D_X8R8G8B8;
				break;

			case 16:
				content_srf.format = SVGA3D_R5G6B5;
				break;

			case 8:
				content_srf.format = SVGA3D_P8;
				break;

			default:
				DRM_ERROR("Invalid format\n");
				ret = -EINVAL;
				goto err_unref_content;
			}

			content_srf.flags             = 0;
			content_srf.mip_levels[0]     = 1;
			content_srf.multisample_count = 0;
		} else {

			stdu->content_fb_type = SEPARATE_SURFACE;

			new_vfbs = vmw_framebuffer_to_vfbs(new_fb);
			content_srf = *new_vfbs->surface;
		}


		ret = vmw_surface_gb_priv_define(crtc->dev,
				0, /* because kernel visible only */
				content_srf.flags,
				content_srf.format,
				true, /* a scanout buffer */
				content_srf.mip_levels[0],
				content_srf.multisample_count,
				0,
				display_base_size,
				&display_srf);
		if (unlikely(ret != 0)) {
			DRM_ERROR("Cannot allocate a display FB.\n");
			goto err_unref_content;
		}

		stdu->display_srf = display_srf;
	} else {
		new_vfbs = vmw_framebuffer_to_vfbs(new_fb);
		stdu->display_srf = new_vfbs->surface;
	}


	ret = vmw_stdu_pin_display(stdu);
	if (unlikely(ret != 0)) {
		stdu->display_srf = NULL;
		goto err_unref_content;
	}

	vmw_svga_enable(dev_priv);

	/*
	 * Steps to displaying a surface, assume surface is already
	 * bound:
	 *   1.  define a screen target
	 *   2.  bind a fb to the screen target
	 *   3.  update that screen target (this is done later by
	 *       vmw_kms_stdu_do_surface_dirty_or_present)
	 */
	ret = vmw_stdu_define_st(dev_priv, stdu);
	if (unlikely(ret != 0))
		goto err_unpin_display_and_content;

	ret = vmw_stdu_bind_st(dev_priv, stdu, &stdu->display_srf->res);
	if (unlikely(ret != 0))
		goto err_unpin_destroy_st;


	connector->encoder = encoder;
	encoder->crtc      = crtc;

	crtc->mode    = *mode;
	crtc->primary->fb = new_fb;
	crtc->enabled = true;

	return ret;

err_unpin_destroy_st:
	vmw_stdu_destroy_st(dev_priv, stdu);
err_unpin_display_and_content:
	vmw_stdu_unpin_display(stdu);
err_unref_content:
	stdu->content_fb = NULL;
	return ret;
}



/**
 * vmw_stdu_crtc_page_flip - Binds a buffer to a screen target
 *
 * @crtc: CRTC to attach FB to
 * @fb: FB to attach
 * @event: Event to be posted. This event should've been alloced
 *         using k[mz]alloc, and should've been completely initialized.
 * @page_flip_flags: Input flags.
 *
 * If the STDU uses the same display and content buffers, i.e. a true flip,
 * this function will replace the existing display buffer with the new content
 * buffer.
 *
 * If the STDU uses different display and content buffers, i.e. a blit, then
 * only the content buffer will be updated.
 *
 * RETURNS:
 * 0 on success, error code on failure
 */
static int vmw_stdu_crtc_page_flip(struct drm_crtc *crtc,
				   struct drm_framebuffer *new_fb,
				   struct drm_pending_vblank_event *event,
				   uint32_t flags)

{
	struct vmw_private *dev_priv = vmw_priv(crtc->dev);
	struct vmw_screen_target_display_unit *stdu;
	int ret;

	if (crtc == NULL)
		return -EINVAL;

	dev_priv          = vmw_priv(crtc->dev);
	stdu              = vmw_crtc_to_stdu(crtc);
	crtc->primary->fb = new_fb;
	stdu->content_fb  = new_fb;

	if (stdu->display_srf) {
		/*
		 * If the display surface is the same as the content surface
		 * then remove the reference
		 */
		if (stdu->content_fb_type == SAME_AS_DISPLAY) {
			if (stdu->defined) {
				/* Unbind the current surface */
				ret = vmw_stdu_bind_st(dev_priv, stdu, NULL);
				if (unlikely(ret != 0))
					goto err_out;
			}
			vmw_stdu_unpin_display(stdu);
			stdu->display_srf = NULL;
		}
	}


	if (!new_fb) {
		/* Blanks the display */
		(void) vmw_stdu_update_st(dev_priv, stdu);

		return 0;
	}


	if (stdu->content_fb_type == SAME_AS_DISPLAY) {
		stdu->display_srf = vmw_framebuffer_to_vfbs(new_fb)->surface;
		ret = vmw_stdu_pin_display(stdu);
		if (ret) {
			stdu->display_srf = NULL;
			goto err_out;
		}

		/* Bind display surface */
		ret = vmw_stdu_bind_st(dev_priv, stdu, &stdu->display_srf->res);
		if (unlikely(ret != 0))
			goto err_unpin_display_and_content;
	}

	/* Update display surface: after this point everything is bound */
	ret = vmw_stdu_update_st(dev_priv, stdu);
	if (unlikely(ret != 0))
		return ret;

	if (event) {
		struct vmw_fence_obj *fence = NULL;
		struct drm_file *file_priv = event->base.file_priv;

		vmw_execbuf_fence_commands(NULL, dev_priv, &fence, NULL);
		if (!fence)
			return -ENOMEM;

		ret = vmw_event_fence_action_queue(file_priv, fence,
						   &event->base,
						   &event->event.tv_sec,
						   &event->event.tv_usec,
						   true);
		vmw_fence_obj_unreference(&fence);
	} else {
		vmw_fifo_flush(dev_priv, false);
	}

	return ret;

err_unpin_display_and_content:
	vmw_stdu_unpin_display(stdu);
err_out:
	crtc->primary->fb = NULL;
	stdu->content_fb = NULL;
	return ret;
}


/**
 * vmw_stdu_dmabuf_clip - Callback to encode a suface DMA command cliprect
 *
 * @dirty: The closure structure.
 *
 * Encodes a surface DMA command cliprect and updates the bounding box
 * for the DMA.
 */
static void vmw_stdu_dmabuf_clip(struct vmw_kms_dirty *dirty)
{
	struct vmw_stdu_dirty *ddirty =
		container_of(dirty, struct vmw_stdu_dirty, base);
	struct vmw_stdu_dma *cmd = dirty->cmd;
	struct SVGA3dCopyBox *blit = (struct SVGA3dCopyBox *) &cmd[1];

	blit += dirty->num_hits;
	blit->srcx = dirty->fb_x;
	blit->srcy = dirty->fb_y;
	blit->x = dirty->unit_x1;
	blit->y = dirty->unit_y1;
	blit->d = 1;
	blit->w = dirty->unit_x2 - dirty->unit_x1;
	blit->h = dirty->unit_y2 - dirty->unit_y1;
	dirty->num_hits++;

	if (ddirty->transfer != SVGA3D_WRITE_HOST_VRAM)
		return;

	/* Destination bounding box */
	ddirty->left = min_t(s32, ddirty->left, dirty->unit_x1);
	ddirty->top = min_t(s32, ddirty->top, dirty->unit_y1);
	ddirty->right = max_t(s32, ddirty->right, dirty->unit_x2);
	ddirty->bottom = max_t(s32, ddirty->bottom, dirty->unit_y2);
}

/**
 * vmw_stdu_dmabuf_fifo_commit - Callback to fill in and submit a DMA command.
 *
 * @dirty: The closure structure.
 *
 * Fills in the missing fields in a DMA command, and optionally encodes
 * a screen target update command, depending on transfer direction.
 */
static void vmw_stdu_dmabuf_fifo_commit(struct vmw_kms_dirty *dirty)
{
	struct vmw_stdu_dirty *ddirty =
		container_of(dirty, struct vmw_stdu_dirty, base);
	struct vmw_screen_target_display_unit *stdu =
		container_of(dirty->unit, typeof(*stdu), base);
	struct vmw_stdu_dma *cmd = dirty->cmd;
	struct SVGA3dCopyBox *blit = (struct SVGA3dCopyBox *) &cmd[1];
	SVGA3dCmdSurfaceDMASuffix *suffix =
		(SVGA3dCmdSurfaceDMASuffix *) &blit[dirty->num_hits];
	size_t blit_size = sizeof(*blit) * dirty->num_hits + sizeof(*suffix);

	if (!dirty->num_hits) {
		vmw_fifo_commit(dirty->dev_priv, 0);
		return;
	}

	cmd->header.id = SVGA_3D_CMD_SURFACE_DMA;
	cmd->header.size = sizeof(cmd->body) + blit_size;
	vmw_bo_get_guest_ptr(&ddirty->buf->base, &cmd->body.guest.ptr);
	cmd->body.guest.pitch = ddirty->pitch;
	cmd->body.host.sid = stdu->display_srf->res.id;
	cmd->body.host.face = 0;
	cmd->body.host.mipmap = 0;
	cmd->body.transfer = ddirty->transfer;
	suffix->suffixSize = sizeof(*suffix);
	suffix->maximumOffset = ddirty->buf->base.num_pages * PAGE_SIZE;

	if (ddirty->transfer == SVGA3D_WRITE_HOST_VRAM) {
		blit_size += sizeof(struct vmw_stdu_update);

		vmw_stdu_populate_update(&suffix[1], stdu->base.unit,
					 ddirty->left, ddirty->right,
					 ddirty->top, ddirty->bottom);
	}

	vmw_fifo_commit(dirty->dev_priv, sizeof(*cmd) + blit_size);

	ddirty->left = ddirty->top = S32_MAX;
	ddirty->right = ddirty->bottom = S32_MIN;
}

/**
 * vmw_kms_stdu_dma - Perform a DMA transfer between a dma-buffer backed
 * framebuffer and the screen target system.
 *
 * @dev_priv: Pointer to the device private structure.
 * @file_priv: Pointer to a struct drm-file identifying the caller. May be
 * set to NULL, but then @user_fence_rep must also be set to NULL.
 * @vfb: Pointer to the dma-buffer backed framebuffer.
 * @clips: Array of clip rects. Either @clips or @vclips must be NULL.
 * @vclips: Alternate array of clip rects. Either @clips or @vclips must
 * be NULL.
 * @num_clips: Number of clip rects in @clips or @vclips.
 * @increment: Increment to use when looping over @clips or @vclips.
 * @to_surface: Whether to DMA to the screen target system as opposed to
 * from the screen target system.
 * @interruptible: Whether to perform waits interruptible if possible.
 *
 * If DMA-ing till the screen target system, the function will also notify
 * the screen target system that a bounding box of the cliprects has been
 * updated.
 * Returns 0 on success, negative error code on failure. -ERESTARTSYS if
 * interrupted.
 */
int vmw_kms_stdu_dma(struct vmw_private *dev_priv,
		     struct drm_file *file_priv,
		     struct vmw_framebuffer *vfb,
		     struct drm_vmw_fence_rep __user *user_fence_rep,
		     struct drm_clip_rect *clips,
		     struct drm_vmw_rect *vclips,
		     uint32_t num_clips,
		     int increment,
		     bool to_surface,
		     bool interruptible)
{
	struct vmw_dma_buffer *buf =
		container_of(vfb, struct vmw_framebuffer_dmabuf, base)->buffer;
	struct vmw_stdu_dirty ddirty;
	int ret;

	ret = vmw_kms_helper_buffer_prepare(dev_priv, buf, interruptible,
					    false);
	if (ret)
		return ret;

	ddirty.transfer = (to_surface) ? SVGA3D_WRITE_HOST_VRAM :
		SVGA3D_READ_HOST_VRAM;
	ddirty.left = ddirty.top = S32_MAX;
	ddirty.right = ddirty.bottom = S32_MIN;
	ddirty.pitch = vfb->base.pitches[0];
	ddirty.buf = buf;
	ddirty.base.fifo_commit = vmw_stdu_dmabuf_fifo_commit;
	ddirty.base.clip = vmw_stdu_dmabuf_clip;
	ddirty.base.fifo_reserve_size = sizeof(struct vmw_stdu_dma) +
		num_clips * sizeof(SVGA3dCopyBox) +
		sizeof(SVGA3dCmdSurfaceDMASuffix);
	if (to_surface)
		ddirty.base.fifo_reserve_size += sizeof(struct vmw_stdu_update);

	ret = vmw_kms_helper_dirty(dev_priv, vfb, clips, vclips,
				   0, 0, num_clips, increment, &ddirty.base);
	vmw_kms_helper_buffer_finish(dev_priv, file_priv, buf, NULL,
				     user_fence_rep);

	return ret;
}

/**
 * vmw_stdu_surface_clip - Callback to encode a surface copy command cliprect
 *
 * @dirty: The closure structure.
 *
 * Encodes a surface copy command cliprect and updates the bounding box
 * for the copy.
 */
static void vmw_kms_stdu_surface_clip(struct vmw_kms_dirty *dirty)
{
	struct vmw_stdu_dirty *sdirty =
		container_of(dirty, struct vmw_stdu_dirty, base);
	struct vmw_stdu_surface_copy *cmd = dirty->cmd;
	struct vmw_screen_target_display_unit *stdu =
		container_of(dirty->unit, typeof(*stdu), base);

	if (sdirty->sid != stdu->display_srf->res.id) {
		struct SVGA3dCopyBox *blit = (struct SVGA3dCopyBox *) &cmd[1];

		blit += dirty->num_hits;
		blit->srcx = dirty->fb_x;
		blit->srcy = dirty->fb_y;
		blit->x = dirty->unit_x1;
		blit->y = dirty->unit_y1;
		blit->d = 1;
		blit->w = dirty->unit_x2 - dirty->unit_x1;
		blit->h = dirty->unit_y2 - dirty->unit_y1;
	}

	dirty->num_hits++;

	/* Destination bounding box */
	sdirty->left = min_t(s32, sdirty->left, dirty->unit_x1);
	sdirty->top = min_t(s32, sdirty->top, dirty->unit_y1);
	sdirty->right = max_t(s32, sdirty->right, dirty->unit_x2);
	sdirty->bottom = max_t(s32, sdirty->bottom, dirty->unit_y2);
}

/**
 * vmw_stdu_surface_fifo_commit - Callback to fill in and submit a surface
 * copy command.
 *
 * @dirty: The closure structure.
 *
 * Fills in the missing fields in a surface copy command, and encodes a screen
 * target update command.
 */
static void vmw_kms_stdu_surface_fifo_commit(struct vmw_kms_dirty *dirty)
{
	struct vmw_stdu_dirty *sdirty =
		container_of(dirty, struct vmw_stdu_dirty, base);
	struct vmw_screen_target_display_unit *stdu =
		container_of(dirty->unit, typeof(*stdu), base);
	struct vmw_stdu_surface_copy *cmd = dirty->cmd;
	struct vmw_stdu_update *update;
	size_t blit_size = sizeof(SVGA3dCopyBox) * dirty->num_hits;
	size_t commit_size;

	if (!dirty->num_hits) {
		vmw_fifo_commit(dirty->dev_priv, 0);
		return;
	}

	if (sdirty->sid != stdu->display_srf->res.id) {
		struct SVGA3dCopyBox *blit = (struct SVGA3dCopyBox *) &cmd[1];

		cmd->header.id = SVGA_3D_CMD_SURFACE_COPY;
		cmd->header.size = sizeof(cmd->body) + blit_size;
		cmd->body.src.sid = sdirty->sid;
		cmd->body.dest.sid = stdu->display_srf->res.id;
		update = (struct vmw_stdu_update *) &blit[dirty->num_hits];
		commit_size = sizeof(*cmd) + blit_size + sizeof(*update);
	} else {
		update = dirty->cmd;
		commit_size = sizeof(*update);
	}

	vmw_stdu_populate_update(update, stdu->base.unit, sdirty->left,
				 sdirty->right, sdirty->top, sdirty->bottom);

	vmw_fifo_commit(dirty->dev_priv, commit_size);

	sdirty->left = sdirty->top = S32_MAX;
	sdirty->right = sdirty->bottom = S32_MIN;
}

/**
 * vmw_kms_stdu_surface_dirty - Dirty part of a surface backed framebuffer
 *
 * @dev_priv: Pointer to the device private structure.
 * @framebuffer: Pointer to the surface-buffer backed framebuffer.
 * @clips: Array of clip rects. Either @clips or @vclips must be NULL.
 * @vclips: Alternate array of clip rects. Either @clips or @vclips must
 * be NULL.
 * @srf: Pointer to surface to blit from. If NULL, the surface attached
 * to @framebuffer will be used.
 * @dest_x: X coordinate offset to align @srf with framebuffer coordinates.
 * @dest_y: Y coordinate offset to align @srf with framebuffer coordinates.
 * @num_clips: Number of clip rects in @clips.
 * @inc: Increment to use when looping over @clips.
 * @out_fence: If non-NULL, will return a ref-counted pointer to a
 * struct vmw_fence_obj. The returned fence pointer may be NULL in which
 * case the device has already synchronized.
 *
 * Returns 0 on success, negative error code on failure. -ERESTARTSYS if
 * interrupted.
 */
int vmw_kms_stdu_surface_dirty(struct vmw_private *dev_priv,
			       struct vmw_framebuffer *framebuffer,
			       struct drm_clip_rect *clips,
			       struct drm_vmw_rect *vclips,
			       struct vmw_resource *srf,
			       s32 dest_x,
			       s32 dest_y,
			       unsigned num_clips, int inc,
			       struct vmw_fence_obj **out_fence)
{
	struct vmw_framebuffer_surface *vfbs =
		container_of(framebuffer, typeof(*vfbs), base);
	struct vmw_stdu_dirty sdirty;
	int ret;

	if (!srf)
		srf = &vfbs->surface->res;

	ret = vmw_kms_helper_resource_prepare(srf, true);
	if (ret)
		return ret;

	if (vfbs->is_dmabuf_proxy) {
		ret = vmw_kms_update_proxy(srf, clips, num_clips, inc);
		if (ret)
			goto out_finish;
	}

	sdirty.base.fifo_commit = vmw_kms_stdu_surface_fifo_commit;
	sdirty.base.clip = vmw_kms_stdu_surface_clip;
	sdirty.base.fifo_reserve_size = sizeof(struct vmw_stdu_surface_copy) +
		sizeof(SVGA3dCopyBox) * num_clips +
		sizeof(struct vmw_stdu_update);
	sdirty.sid = srf->id;
	sdirty.left = sdirty.top = S32_MAX;
	sdirty.right = sdirty.bottom = S32_MIN;

	ret = vmw_kms_helper_dirty(dev_priv, framebuffer, clips, vclips,
				   dest_x, dest_y, num_clips, inc,
				   &sdirty.base);
out_finish:
	vmw_kms_helper_resource_finish(srf, out_fence);

	return ret;
}


/*
 *  Screen Target CRTC dispatch table
 */
static struct drm_crtc_funcs vmw_stdu_crtc_funcs = {
	.save = vmw_du_crtc_save,
	.restore = vmw_du_crtc_restore,
	.cursor_set2 = vmw_du_crtc_cursor_set2,
	.cursor_move = vmw_du_crtc_cursor_move,
	.gamma_set = vmw_du_crtc_gamma_set,
	.destroy = vmw_stdu_crtc_destroy,
	.set_config = vmw_stdu_crtc_set_config,
	.page_flip = vmw_stdu_crtc_page_flip,
};



/******************************************************************************
 * Screen Target Display Unit Encoder Functions
 *****************************************************************************/

/**
 * vmw_stdu_encoder_destroy - cleans up the STDU
 *
 * @encoder: used the get the containing STDU
 *
 * vmwgfx cleans up crtc/encoder/connector all at the same time so technically
 * this can be a no-op.  Nevertheless, it doesn't hurt of have this in case
 * the common KMS code changes and somehow vmw_stdu_crtc_destroy() doesn't
 * get called.
 */
static void vmw_stdu_encoder_destroy(struct drm_encoder *encoder)
{
	vmw_stdu_destroy(vmw_encoder_to_stdu(encoder));
}

static struct drm_encoder_funcs vmw_stdu_encoder_funcs = {
	.destroy = vmw_stdu_encoder_destroy,
};



/******************************************************************************
 * Screen Target Display Unit Connector Functions
 *****************************************************************************/

/**
 * vmw_stdu_connector_destroy - cleans up the STDU
 *
 * @connector: used to get the containing STDU
 *
 * vmwgfx cleans up crtc/encoder/connector all at the same time so technically
 * this can be a no-op.  Nevertheless, it doesn't hurt of have this in case
 * the common KMS code changes and somehow vmw_stdu_crtc_destroy() doesn't
 * get called.
 */
static void vmw_stdu_connector_destroy(struct drm_connector *connector)
{
	vmw_stdu_destroy(vmw_connector_to_stdu(connector));
}



static struct drm_connector_funcs vmw_stdu_connector_funcs = {
	.dpms = vmw_du_connector_dpms,
	.save = vmw_du_connector_save,
	.restore = vmw_du_connector_restore,
	.detect = vmw_du_connector_detect,
	.fill_modes = vmw_du_connector_fill_modes,
	.set_property = vmw_du_connector_set_property,
	.destroy = vmw_stdu_connector_destroy,
};



/**
 * vmw_stdu_init - Sets up a Screen Target Display Unit
 *
 * @dev_priv: VMW DRM device
 * @unit: unit number range from 0 to VMWGFX_NUM_DISPLAY_UNITS
 *
 * This function is called once per CRTC, and allocates one Screen Target
 * display unit to represent that CRTC.  Since the SVGA device does not separate
 * out encoder and connector, they are represented as part of the STDU as well.
 */
static int vmw_stdu_init(struct vmw_private *dev_priv, unsigned unit)
{
	struct vmw_screen_target_display_unit *stdu;
	struct drm_device *dev = dev_priv->dev;
	struct drm_connector *connector;
	struct drm_encoder *encoder;
	struct drm_crtc *crtc;


	stdu = kzalloc(sizeof(*stdu), GFP_KERNEL);
	if (!stdu)
		return -ENOMEM;

	stdu->base.unit = unit;
	crtc = &stdu->base.crtc;
	encoder = &stdu->base.encoder;
	connector = &stdu->base.connector;

	stdu->base.pref_active = (unit == 0);
	stdu->base.pref_width  = dev_priv->initial_width;
	stdu->base.pref_height = dev_priv->initial_height;
	stdu->base.is_implicit = true;

	drm_connector_init(dev, connector, &vmw_stdu_connector_funcs,
			   DRM_MODE_CONNECTOR_VIRTUAL);
	connector->status = vmw_du_connector_detect(connector, false);

	drm_encoder_init(dev, encoder, &vmw_stdu_encoder_funcs,
			 DRM_MODE_ENCODER_VIRTUAL);
	drm_mode_connector_attach_encoder(connector, encoder);
	encoder->possible_crtcs = (1 << unit);
	encoder->possible_clones = 0;

	(void) drm_connector_register(connector);

	drm_crtc_init(dev, crtc, &vmw_stdu_crtc_funcs);

	drm_mode_crtc_set_gamma_size(crtc, 256);

	drm_object_attach_property(&connector->base,
				   dev->mode_config.dirty_info_property,
				   1);

	return 0;
}



/**
 *  vmw_stdu_destroy - Cleans up a vmw_screen_target_display_unit
 *
 *  @stdu:  Screen Target Display Unit to be destroyed
 *
 *  Clean up after vmw_stdu_init
 */
static void vmw_stdu_destroy(struct vmw_screen_target_display_unit *stdu)
{
	vmw_stdu_unpin_display(stdu);

	vmw_du_cleanup(&stdu->base);
	kfree(stdu);
}



/******************************************************************************
 * Screen Target Display KMS Functions
 *
 * These functions are called by the common KMS code in vmwgfx_kms.c
 *****************************************************************************/

/**
 * vmw_kms_stdu_init_display - Initializes a Screen Target based display
 *
 * @dev_priv: VMW DRM device
 *
 * This function initialize a Screen Target based display device.  It checks
 * the capability bits to make sure the underlying hardware can support
 * screen targets, and then creates the maximum number of CRTCs, a.k.a Display
 * Units, as supported by the display hardware.
 *
 * RETURNS:
 * 0 on success, error code otherwise
 */
int vmw_kms_stdu_init_display(struct vmw_private *dev_priv)
{
	struct drm_device *dev = dev_priv->dev;
	int i, ret;


	/* Do nothing if Screen Target support is turned off */
	if (!VMWGFX_ENABLE_SCREEN_TARGET_OTABLE)
		return -ENOSYS;

	if (!(dev_priv->capabilities & SVGA_CAP_GBOBJECTS))
		return -ENOSYS;

	ret = drm_vblank_init(dev, VMWGFX_NUM_DISPLAY_UNITS);
	if (unlikely(ret != 0))
		return ret;

	ret = drm_mode_create_dirty_info_property(dev);
	if (unlikely(ret != 0))
		goto err_vblank_cleanup;

	dev_priv->active_display_unit = vmw_du_screen_target;

	for (i = 0; i < VMWGFX_NUM_DISPLAY_UNITS; ++i) {
		ret = vmw_stdu_init(dev_priv, i);

		if (unlikely(ret != 0)) {
			DRM_ERROR("Failed to initialize STDU %d", i);
			goto err_vblank_cleanup;
		}
	}

	DRM_INFO("Screen Target Display device initialized\n");

	return 0;

err_vblank_cleanup:
	drm_vblank_cleanup(dev);
	return ret;
}



/**
 * vmw_kms_stdu_close_display - Cleans up after vmw_kms_stdu_init_display
 *
 * @dev_priv: VMW DRM device
 *
 * Frees up any resources allocated by vmw_kms_stdu_init_display
 *
 * RETURNS:
 * 0 on success
 */
int vmw_kms_stdu_close_display(struct vmw_private *dev_priv)
{
	struct drm_device *dev = dev_priv->dev;

	drm_vblank_cleanup(dev);

	return 0;
}