Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
   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
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
/*
 * drivers/ata/sata_dwc_460ex.c
 *
 * Synopsys DesignWare Cores (DWC) SATA host driver
 *
 * Author: Mark Miesfeld <mmiesfeld@amcc.com>
 *
 * Ported from 2.6.19.2 to 2.6.25/26 by Stefan Roese <sr@denx.de>
 * Copyright 2008 DENX Software Engineering
 *
 * Based on versions provided by AMCC and Synopsys which are:
 *          Copyright 2006 Applied Micro Circuits Corporation
 *          COPYRIGHT (C) 2005  SYNOPSYS, INC.  ALL RIGHTS RESERVED
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */

#ifdef CONFIG_SATA_DWC_DEBUG
#define DEBUG
#endif

#ifdef CONFIG_SATA_DWC_VDEBUG
#define VERBOSE_DEBUG
#define DEBUG_NCQ
#endif

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/libata.h>
#include <linux/slab.h>
#include "libata.h"

#include <scsi/scsi_host.h>
#include <scsi/scsi_cmnd.h>

/* These two are defined in "libata.h" */
#undef	DRV_NAME
#undef	DRV_VERSION

#define DRV_NAME        "sata-dwc"
#define DRV_VERSION     "1.3"

/* SATA DMA driver Globals */
#define DMA_NUM_CHANS		1
#define DMA_NUM_CHAN_REGS	8

/* SATA DMA Register definitions */
#define AHB_DMA_BRST_DFLT	64	/* 16 data items burst length*/

struct dmareg {
	u32 low;		/* Low bits 0-31 */
	u32 high;		/* High bits 32-63 */
};

/* DMA Per Channel registers */
struct dma_chan_regs {
	struct dmareg sar;	/* Source Address */
	struct dmareg dar;	/* Destination address */
	struct dmareg llp;	/* Linked List Pointer */
	struct dmareg ctl;	/* Control */
	struct dmareg sstat;	/* Source Status not implemented in core */
	struct dmareg dstat;	/* Destination Status not implemented in core*/
	struct dmareg sstatar;	/* Source Status Address not impl in core */
	struct dmareg dstatar;	/* Destination Status Address not implemente */
	struct dmareg cfg;	/* Config */
	struct dmareg sgr;	/* Source Gather */
	struct dmareg dsr;	/* Destination Scatter */
};

/* Generic Interrupt Registers */
struct dma_interrupt_regs {
	struct dmareg tfr;	/* Transfer Interrupt */
	struct dmareg block;	/* Block Interrupt */
	struct dmareg srctran;	/* Source Transfer Interrupt */
	struct dmareg dsttran;	/* Dest Transfer Interrupt */
	struct dmareg error;	/* Error */
};

struct ahb_dma_regs {
	struct dma_chan_regs	chan_regs[DMA_NUM_CHAN_REGS];
	struct dma_interrupt_regs interrupt_raw;	/* Raw Interrupt */
	struct dma_interrupt_regs interrupt_status;	/* Interrupt Status */
	struct dma_interrupt_regs interrupt_mask;	/* Interrupt Mask */
	struct dma_interrupt_regs interrupt_clear;	/* Interrupt Clear */
	struct dmareg		statusInt;	/* Interrupt combined*/
	struct dmareg		rq_srcreg;	/* Src Trans Req */
	struct dmareg		rq_dstreg;	/* Dst Trans Req */
	struct dmareg		rq_sgl_srcreg;	/* Sngl Src Trans Req*/
	struct dmareg		rq_sgl_dstreg;	/* Sngl Dst Trans Req*/
	struct dmareg		rq_lst_srcreg;	/* Last Src Trans Req*/
	struct dmareg		rq_lst_dstreg;	/* Last Dst Trans Req*/
	struct dmareg		dma_cfg;		/* DMA Config */
	struct dmareg		dma_chan_en;		/* DMA Channel Enable*/
	struct dmareg		dma_id;			/* DMA ID */
	struct dmareg		dma_test;		/* DMA Test */
	struct dmareg		res1;			/* reserved */
	struct dmareg		res2;			/* reserved */
	/*
	 * DMA Comp Params
	 * Param 6 = dma_param[0], Param 5 = dma_param[1],
	 * Param 4 = dma_param[2] ...
	 */
	struct dmareg		dma_params[6];
};

/* Data structure for linked list item */
struct lli {
	u32		sar;		/* Source Address */
	u32		dar;		/* Destination address */
	u32		llp;		/* Linked List Pointer */
	struct dmareg	ctl;		/* Control */
	struct dmareg	dstat;		/* Destination Status */
};

enum {
	SATA_DWC_DMAC_LLI_SZ =	(sizeof(struct lli)),
	SATA_DWC_DMAC_LLI_NUM =	256,
	SATA_DWC_DMAC_LLI_TBL_SZ = (SATA_DWC_DMAC_LLI_SZ * \
					SATA_DWC_DMAC_LLI_NUM),
	SATA_DWC_DMAC_TWIDTH_BYTES = 4,
	SATA_DWC_DMAC_CTRL_TSIZE_MAX = (0x00000800 * \
						SATA_DWC_DMAC_TWIDTH_BYTES),
};

/* DMA Register Operation Bits */
enum {
	DMA_EN	=		0x00000001, /* Enable AHB DMA */
	DMA_CTL_LLP_SRCEN =	0x10000000, /* Blk chain enable Src */
	DMA_CTL_LLP_DSTEN =	0x08000000, /* Blk chain enable Dst */
};

#define	DMA_CTL_BLK_TS(size)	((size) & 0x000000FFF)	/* Blk Transfer size */
#define DMA_CHANNEL(ch)		(0x00000001 << (ch))	/* Select channel */
	/* Enable channel */
#define	DMA_ENABLE_CHAN(ch)	((0x00000001 << (ch)) |			\
				 ((0x000000001 << (ch)) << 8))
	/* Disable channel */
#define	DMA_DISABLE_CHAN(ch)	(0x00000000 | ((0x000000001 << (ch)) << 8))
	/* Transfer Type & Flow Controller */
#define	DMA_CTL_TTFC(type)	(((type) & 0x7) << 20)
#define	DMA_CTL_SMS(num)	(((num) & 0x3) << 25) /* Src Master Select */
#define	DMA_CTL_DMS(num)	(((num) & 0x3) << 23)/* Dst Master Select */
	/* Src Burst Transaction Length */
#define DMA_CTL_SRC_MSIZE(size) (((size) & 0x7) << 14)
	/* Dst Burst Transaction Length */
#define	DMA_CTL_DST_MSIZE(size) (((size) & 0x7) << 11)
	/* Source Transfer Width */
#define	DMA_CTL_SRC_TRWID(size) (((size) & 0x7) << 4)
	/* Destination Transfer Width */
#define	DMA_CTL_DST_TRWID(size) (((size) & 0x7) << 1)

/* Assign HW handshaking interface (x) to destination / source peripheral */
#define	DMA_CFG_HW_HS_DEST(int_num) (((int_num) & 0xF) << 11)
#define	DMA_CFG_HW_HS_SRC(int_num) (((int_num) & 0xF) << 7)
#define	DMA_CFG_HW_CH_PRIOR(int_num) (((int_num) & 0xF) << 5)
#define	DMA_LLP_LMS(addr, master) (((addr) & 0xfffffffc) | (master))

/*
 * This define is used to set block chaining disabled in the control low
 * register.  It is already in little endian format so it can be &'d dirctly.
 * It is essentially: cpu_to_le32(~(DMA_CTL_LLP_SRCEN | DMA_CTL_LLP_DSTEN))
 */
enum {
	DMA_CTL_LLP_DISABLE_LE32 = 0xffffffe7,
	DMA_CTL_TTFC_P2M_DMAC =	0x00000002, /* Per to mem, DMAC cntr */
	DMA_CTL_TTFC_M2P_PER =	0x00000003, /* Mem to per, peripheral cntr */
	DMA_CTL_SINC_INC =	0x00000000, /* Source Address Increment */
	DMA_CTL_SINC_DEC =	0x00000200,
	DMA_CTL_SINC_NOCHANGE =	0x00000400,
	DMA_CTL_DINC_INC =	0x00000000, /* Destination Address Increment */
	DMA_CTL_DINC_DEC =	0x00000080,
	DMA_CTL_DINC_NOCHANGE =	0x00000100,
	DMA_CTL_INT_EN =	0x00000001, /* Interrupt Enable */

/* Channel Configuration Register high bits */
	DMA_CFG_FCMOD_REQ =	0x00000001, /* Flow Control - request based */
	DMA_CFG_PROTCTL	=	(0x00000003 << 2),/* Protection Control */

/* Channel Configuration Register low bits */
	DMA_CFG_RELD_DST =	0x80000000, /* Reload Dest / Src Addr */
	DMA_CFG_RELD_SRC =	0x40000000,
	DMA_CFG_HS_SELSRC =	0x00000800, /* Software handshake Src/ Dest */
	DMA_CFG_HS_SELDST =	0x00000400,
	DMA_CFG_FIFOEMPTY =     (0x00000001 << 9), /* FIFO Empty bit */

/* Channel Linked List Pointer Register */
	DMA_LLP_AHBMASTER1 =	0,	/* List Master Select */
	DMA_LLP_AHBMASTER2 =	1,

	SATA_DWC_MAX_PORTS = 1,

	SATA_DWC_SCR_OFFSET = 0x24,
	SATA_DWC_REG_OFFSET = 0x64,
};

/* DWC SATA Registers */
struct sata_dwc_regs {
	u32 fptagr;		/* 1st party DMA tag */
	u32 fpbor;		/* 1st party DMA buffer offset */
	u32 fptcr;		/* 1st party DMA Xfr count */
	u32 dmacr;		/* DMA Control */
	u32 dbtsr;		/* DMA Burst Transac size */
	u32 intpr;		/* Interrupt Pending */
	u32 intmr;		/* Interrupt Mask */
	u32 errmr;		/* Error Mask */
	u32 llcr;		/* Link Layer Control */
	u32 phycr;		/* PHY Control */
	u32 physr;		/* PHY Status */
	u32 rxbistpd;		/* Recvd BIST pattern def register */
	u32 rxbistpd1;		/* Recvd BIST data dword1 */
	u32 rxbistpd2;		/* Recvd BIST pattern data dword2 */
	u32 txbistpd;		/* Trans BIST pattern def register */
	u32 txbistpd1;		/* Trans BIST data dword1 */
	u32 txbistpd2;		/* Trans BIST data dword2 */
	u32 bistcr;		/* BIST Control Register */
	u32 bistfctr;		/* BIST FIS Count Register */
	u32 bistsr;		/* BIST Status Register */
	u32 bistdecr;		/* BIST Dword Error count register */
	u32 res[15];		/* Reserved locations */
	u32 testr;		/* Test Register */
	u32 versionr;		/* Version Register */
	u32 idr;		/* ID Register */
	u32 unimpl[192];	/* Unimplemented */
	u32 dmadr[256];	/* FIFO Locations in DMA Mode */
};

enum {
	SCR_SCONTROL_DET_ENABLE	=	0x00000001,
	SCR_SSTATUS_DET_PRESENT	=	0x00000001,
	SCR_SERROR_DIAG_X	=	0x04000000,
/* DWC SATA Register Operations */
	SATA_DWC_TXFIFO_DEPTH	=	0x01FF,
	SATA_DWC_RXFIFO_DEPTH	=	0x01FF,
	SATA_DWC_DMACR_TMOD_TXCHEN =	0x00000004,
	SATA_DWC_DMACR_TXCHEN	= (0x00000001 | SATA_DWC_DMACR_TMOD_TXCHEN),
	SATA_DWC_DMACR_RXCHEN	= (0x00000002 | SATA_DWC_DMACR_TMOD_TXCHEN),
	SATA_DWC_DMACR_TXRXCH_CLEAR =	SATA_DWC_DMACR_TMOD_TXCHEN,
	SATA_DWC_INTPR_DMAT	=	0x00000001,
	SATA_DWC_INTPR_NEWFP	=	0x00000002,
	SATA_DWC_INTPR_PMABRT	=	0x00000004,
	SATA_DWC_INTPR_ERR	=	0x00000008,
	SATA_DWC_INTPR_NEWBIST	=	0x00000010,
	SATA_DWC_INTPR_IPF	=	0x10000000,
	SATA_DWC_INTMR_DMATM	=	0x00000001,
	SATA_DWC_INTMR_NEWFPM	=	0x00000002,
	SATA_DWC_INTMR_PMABRTM	=	0x00000004,
	SATA_DWC_INTMR_ERRM	=	0x00000008,
	SATA_DWC_INTMR_NEWBISTM	=	0x00000010,
	SATA_DWC_LLCR_SCRAMEN	=	0x00000001,
	SATA_DWC_LLCR_DESCRAMEN	=	0x00000002,
	SATA_DWC_LLCR_RPDEN	=	0x00000004,
/* This is all error bits, zero's are reserved fields. */
	SATA_DWC_SERROR_ERR_BITS =	0x0FFF0F03
};

#define SATA_DWC_SCR0_SPD_GET(v)	(((v) >> 4) & 0x0000000F)
#define SATA_DWC_DMACR_TX_CLEAR(v)	(((v) & ~SATA_DWC_DMACR_TXCHEN) |\
						 SATA_DWC_DMACR_TMOD_TXCHEN)
#define SATA_DWC_DMACR_RX_CLEAR(v)	(((v) & ~SATA_DWC_DMACR_RXCHEN) |\
						 SATA_DWC_DMACR_TMOD_TXCHEN)
#define SATA_DWC_DBTSR_MWR(size)	(((size)/4) & SATA_DWC_TXFIFO_DEPTH)
#define SATA_DWC_DBTSR_MRD(size)	((((size)/4) & SATA_DWC_RXFIFO_DEPTH)\
						 << 16)
struct sata_dwc_device {
	struct device		*dev;		/* generic device struct */
	struct ata_probe_ent	*pe;		/* ptr to probe-ent */
	struct ata_host		*host;
	u8			*reg_base;
	struct sata_dwc_regs	*sata_dwc_regs;	/* DW Synopsys SATA specific */
	int			irq_dma;
};

#define SATA_DWC_QCMD_MAX	32

struct sata_dwc_device_port {
	struct sata_dwc_device	*hsdev;
	int			cmd_issued[SATA_DWC_QCMD_MAX];
	struct lli		*llit[SATA_DWC_QCMD_MAX];  /* DMA LLI table */
	dma_addr_t		llit_dma[SATA_DWC_QCMD_MAX];
	u32			dma_chan[SATA_DWC_QCMD_MAX];
	int			dma_pending[SATA_DWC_QCMD_MAX];
};

/*
 * Commonly used DWC SATA driver Macros
 */
#define HSDEV_FROM_HOST(host)  ((struct sata_dwc_device *)\
					(host)->private_data)
#define HSDEV_FROM_AP(ap)  ((struct sata_dwc_device *)\
					(ap)->host->private_data)
#define HSDEVP_FROM_AP(ap)   ((struct sata_dwc_device_port *)\
					(ap)->private_data)
#define HSDEV_FROM_QC(qc)	((struct sata_dwc_device *)\
					(qc)->ap->host->private_data)
#define HSDEV_FROM_HSDEVP(p)	((struct sata_dwc_device *)\
						(hsdevp)->hsdev)

enum {
	SATA_DWC_CMD_ISSUED_NOT		= 0,
	SATA_DWC_CMD_ISSUED_PEND	= 1,
	SATA_DWC_CMD_ISSUED_EXEC	= 2,
	SATA_DWC_CMD_ISSUED_NODATA	= 3,

	SATA_DWC_DMA_PENDING_NONE	= 0,
	SATA_DWC_DMA_PENDING_TX		= 1,
	SATA_DWC_DMA_PENDING_RX		= 2,
};

struct sata_dwc_host_priv {
	void	__iomem	 *scr_addr_sstatus;
	u32	sata_dwc_sactive_issued ;
	u32	sata_dwc_sactive_queued ;
	u32	dma_interrupt_count;
	struct	ahb_dma_regs	*sata_dma_regs;
	struct	device	*dwc_dev;
	int	dma_channel;
};
struct sata_dwc_host_priv host_pvt;
/*
 * Prototypes
 */
static void sata_dwc_bmdma_start_by_tag(struct ata_queued_cmd *qc, u8 tag);
static int sata_dwc_qc_complete(struct ata_port *ap, struct ata_queued_cmd *qc,
				u32 check_status);
static void sata_dwc_dma_xfer_complete(struct ata_port *ap, u32 check_status);
static void sata_dwc_port_stop(struct ata_port *ap);
static void sata_dwc_clear_dmacr(struct sata_dwc_device_port *hsdevp, u8 tag);
static int dma_dwc_init(struct sata_dwc_device *hsdev, int irq);
static void dma_dwc_exit(struct sata_dwc_device *hsdev);
static int dma_dwc_xfer_setup(struct scatterlist *sg, int num_elems,
			      struct lli *lli, dma_addr_t dma_lli,
			      void __iomem *addr, int dir);
static void dma_dwc_xfer_start(int dma_ch);

static const char *get_prot_descript(u8 protocol)
{
	switch ((enum ata_tf_protocols)protocol) {
	case ATA_PROT_NODATA:
		return "ATA no data";
	case ATA_PROT_PIO:
		return "ATA PIO";
	case ATA_PROT_DMA:
		return "ATA DMA";
	case ATA_PROT_NCQ:
		return "ATA NCQ";
	case ATAPI_PROT_NODATA:
		return "ATAPI no data";
	case ATAPI_PROT_PIO:
		return "ATAPI PIO";
	case ATAPI_PROT_DMA:
		return "ATAPI DMA";
	default:
		return "unknown";
	}
}

static const char *get_dma_dir_descript(int dma_dir)
{
	switch ((enum dma_data_direction)dma_dir) {
	case DMA_BIDIRECTIONAL:
		return "bidirectional";
	case DMA_TO_DEVICE:
		return "to device";
	case DMA_FROM_DEVICE:
		return "from device";
	default:
		return "none";
	}
}

static void sata_dwc_tf_dump(struct ata_taskfile *tf)
{
	dev_vdbg(host_pvt.dwc_dev, "taskfile cmd: 0x%02x protocol: %s flags:"
		"0x%lx device: %x\n", tf->command,
		get_prot_descript(tf->protocol), tf->flags, tf->device);
	dev_vdbg(host_pvt.dwc_dev, "feature: 0x%02x nsect: 0x%x lbal: 0x%x "
		"lbam: 0x%x lbah: 0x%x\n", tf->feature, tf->nsect, tf->lbal,
		 tf->lbam, tf->lbah);
	dev_vdbg(host_pvt.dwc_dev, "hob_feature: 0x%02x hob_nsect: 0x%x "
		"hob_lbal: 0x%x hob_lbam: 0x%x hob_lbah: 0x%x\n",
		tf->hob_feature, tf->hob_nsect, tf->hob_lbal, tf->hob_lbam,
		tf->hob_lbah);
}

/*
 * Function: get_burst_length_encode
 * arguments: datalength: length in bytes of data
 * returns value to be programmed in register corresponding to data length
 * This value is effectively the log(base 2) of the length
 */
static  int get_burst_length_encode(int datalength)
{
	int items = datalength >> 2;	/* div by 4 to get lword count */

	if (items >= 64)
		return 5;

	if (items >= 32)
		return 4;

	if (items >= 16)
		return 3;

	if (items >= 8)
		return 2;

	if (items >= 4)
		return 1;

	return 0;
}

static  void clear_chan_interrupts(int c)
{
	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.tfr.low),
		 DMA_CHANNEL(c));
	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.block.low),
		 DMA_CHANNEL(c));
	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.srctran.low),
		 DMA_CHANNEL(c));
	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.dsttran.low),
		 DMA_CHANNEL(c));
	out_le32(&(host_pvt.sata_dma_regs->interrupt_clear.error.low),
		 DMA_CHANNEL(c));
}

/*
 * Function: dma_request_channel
 * arguments: None
 * returns channel number if available else -1
 * This function assigns the next available DMA channel from the list to the
 * requester
 */
static int dma_request_channel(void)
{
	/* Check if the channel is not currently in use */
	if (!(in_le32(&(host_pvt.sata_dma_regs->dma_chan_en.low)) &
		DMA_CHANNEL(host_pvt.dma_channel)))
		return host_pvt.dma_channel;
	dev_err(host_pvt.dwc_dev, "%s Channel %d is currently in use\n",
		__func__, host_pvt.dma_channel);
	return -1;
}

/*
 * Function: dma_dwc_interrupt
 * arguments: irq, dev_id, pt_regs
 * returns channel number if available else -1
 * Interrupt Handler for DW AHB SATA DMA
 */
static irqreturn_t dma_dwc_interrupt(int irq, void *hsdev_instance)
{
	int chan;
	u32 tfr_reg, err_reg;
	unsigned long flags;
	struct sata_dwc_device *hsdev =
		(struct sata_dwc_device *)hsdev_instance;
	struct ata_host *host = (struct ata_host *)hsdev->host;
	struct ata_port *ap;
	struct sata_dwc_device_port *hsdevp;
	u8 tag = 0;
	unsigned int port = 0;

	spin_lock_irqsave(&host->lock, flags);
	ap = host->ports[port];
	hsdevp = HSDEVP_FROM_AP(ap);
	tag = ap->link.active_tag;

	tfr_reg = in_le32(&(host_pvt.sata_dma_regs->interrupt_status.tfr\
			.low));
	err_reg = in_le32(&(host_pvt.sata_dma_regs->interrupt_status.error\
			.low));

	dev_dbg(ap->dev, "eot=0x%08x err=0x%08x pending=%d active port=%d\n",
		tfr_reg, err_reg, hsdevp->dma_pending[tag], port);

	chan = host_pvt.dma_channel;
	if (chan >= 0) {
		/* Check for end-of-transfer interrupt. */
		if (tfr_reg & DMA_CHANNEL(chan)) {
			/*
			 * Each DMA command produces 2 interrupts.  Only
			 * complete the command after both interrupts have been
			 * seen. (See sata_dwc_isr())
			 */
			host_pvt.dma_interrupt_count++;
			sata_dwc_clear_dmacr(hsdevp, tag);

			if (hsdevp->dma_pending[tag] ==
			    SATA_DWC_DMA_PENDING_NONE) {
				dev_err(ap->dev, "DMA not pending eot=0x%08x "
					"err=0x%08x tag=0x%02x pending=%d\n",
					tfr_reg, err_reg, tag,
					hsdevp->dma_pending[tag]);
			}

			if ((host_pvt.dma_interrupt_count % 2) == 0)
				sata_dwc_dma_xfer_complete(ap, 1);

			/* Clear the interrupt */
			out_le32(&(host_pvt.sata_dma_regs->interrupt_clear\
				.tfr.low),
				 DMA_CHANNEL(chan));
		}

		/* Check for error interrupt. */
		if (err_reg & DMA_CHANNEL(chan)) {
			/* TODO Need error handler ! */
			dev_err(ap->dev, "error interrupt err_reg=0x%08x\n",
				err_reg);

			/* Clear the interrupt. */
			out_le32(&(host_pvt.sata_dma_regs->interrupt_clear\
				.error.low),
				 DMA_CHANNEL(chan));
		}
	}
	spin_unlock_irqrestore(&host->lock, flags);
	return IRQ_HANDLED;
}

/*
 * Function: dma_request_interrupts
 * arguments: hsdev
 * returns status
 * This function registers ISR for a particular DMA channel interrupt
 */
static int dma_request_interrupts(struct sata_dwc_device *hsdev, int irq)
{
	int retval = 0;
	int chan = host_pvt.dma_channel;

	if (chan >= 0) {
		/* Unmask error interrupt */
		out_le32(&(host_pvt.sata_dma_regs)->interrupt_mask.error.low,
			 DMA_ENABLE_CHAN(chan));

		/* Unmask end-of-transfer interrupt */
		out_le32(&(host_pvt.sata_dma_regs)->interrupt_mask.tfr.low,
			 DMA_ENABLE_CHAN(chan));
	}

	retval = request_irq(irq, dma_dwc_interrupt, 0, "SATA DMA", hsdev);
	if (retval) {
		dev_err(host_pvt.dwc_dev, "%s: could not get IRQ %d\n",
		__func__, irq);
		return -ENODEV;
	}

	/* Mark this interrupt as requested */
	hsdev->irq_dma = irq;
	return 0;
}

/*
 * Function: map_sg_to_lli
 * The Synopsis driver has a comment proposing that better performance
 * is possible by only enabling interrupts on the last item in the linked list.
 * However, it seems that could be a problem if an error happened on one of the
 * first items.  The transfer would halt, but no error interrupt would occur.
 * Currently this function sets interrupts enabled for each linked list item:
 * DMA_CTL_INT_EN.
 */
static int map_sg_to_lli(struct scatterlist *sg, int num_elems,
			struct lli *lli, dma_addr_t dma_lli,
			void __iomem *dmadr_addr, int dir)
{
	int i, idx = 0;
	int fis_len = 0;
	dma_addr_t next_llp;
	int bl;
	int sms_val, dms_val;

	sms_val = 0;
	dms_val = 1 + host_pvt.dma_channel;
	dev_dbg(host_pvt.dwc_dev, "%s: sg=%p nelem=%d lli=%p dma_lli=0x%08x"
		" dmadr=0x%08x\n", __func__, sg, num_elems, lli, (u32)dma_lli,
		(u32)dmadr_addr);

	bl = get_burst_length_encode(AHB_DMA_BRST_DFLT);

	for (i = 0; i < num_elems; i++, sg++) {
		u32 addr, offset;
		u32 sg_len, len;

		addr = (u32) sg_dma_address(sg);
		sg_len = sg_dma_len(sg);

		dev_dbg(host_pvt.dwc_dev, "%s: elem=%d sg_addr=0x%x sg_len"
			"=%d\n", __func__, i, addr, sg_len);

		while (sg_len) {
			if (idx >= SATA_DWC_DMAC_LLI_NUM) {
				/* The LLI table is not large enough. */
				dev_err(host_pvt.dwc_dev, "LLI table overrun "
				"(idx=%d)\n", idx);
				break;
			}
			len = (sg_len > SATA_DWC_DMAC_CTRL_TSIZE_MAX) ?
				SATA_DWC_DMAC_CTRL_TSIZE_MAX : sg_len;

			offset = addr & 0xffff;
			if ((offset + sg_len) > 0x10000)
				len = 0x10000 - offset;

			/*
			 * Make sure a LLI block is not created that will span
			 * 8K max FIS boundary.  If the block spans such a FIS
			 * boundary, there is a chance that a DMA burst will
			 * cross that boundary -- this results in an error in
			 * the host controller.
			 */
			if (fis_len + len > 8192) {
				dev_dbg(host_pvt.dwc_dev, "SPLITTING: fis_len="
					"%d(0x%x) len=%d(0x%x)\n", fis_len,
					 fis_len, len, len);
				len = 8192 - fis_len;
				fis_len = 0;
			} else {
				fis_len += len;
			}
			if (fis_len == 8192)
				fis_len = 0;

			/*
			 * Set DMA addresses and lower half of control register
			 * based on direction.
			 */
			if (dir == DMA_FROM_DEVICE) {
				lli[idx].dar = cpu_to_le32(addr);
				lli[idx].sar = cpu_to_le32((u32)dmadr_addr);

				lli[idx].ctl.low = cpu_to_le32(
					DMA_CTL_TTFC(DMA_CTL_TTFC_P2M_DMAC) |
					DMA_CTL_SMS(sms_val) |
					DMA_CTL_DMS(dms_val) |
					DMA_CTL_SRC_MSIZE(bl) |
					DMA_CTL_DST_MSIZE(bl) |
					DMA_CTL_SINC_NOCHANGE |
					DMA_CTL_SRC_TRWID(2) |
					DMA_CTL_DST_TRWID(2) |
					DMA_CTL_INT_EN |
					DMA_CTL_LLP_SRCEN |
					DMA_CTL_LLP_DSTEN);
			} else {	/* DMA_TO_DEVICE */
				lli[idx].sar = cpu_to_le32(addr);
				lli[idx].dar = cpu_to_le32((u32)dmadr_addr);

				lli[idx].ctl.low = cpu_to_le32(
					DMA_CTL_TTFC(DMA_CTL_TTFC_M2P_PER) |
					DMA_CTL_SMS(dms_val) |
					DMA_CTL_DMS(sms_val) |
					DMA_CTL_SRC_MSIZE(bl) |
					DMA_CTL_DST_MSIZE(bl) |
					DMA_CTL_DINC_NOCHANGE |
					DMA_CTL_SRC_TRWID(2) |
					DMA_CTL_DST_TRWID(2) |
					DMA_CTL_INT_EN |
					DMA_CTL_LLP_SRCEN |
					DMA_CTL_LLP_DSTEN);
			}

			dev_dbg(host_pvt.dwc_dev, "%s setting ctl.high len: "
				"0x%08x val: 0x%08x\n", __func__,
				len, DMA_CTL_BLK_TS(len / 4));

			/* Program the LLI CTL high register */
			lli[idx].ctl.high = cpu_to_le32(DMA_CTL_BLK_TS\
						(len / 4));

			/* Program the next pointer.  The next pointer must be
			 * the physical address, not the virtual address.
			 */
			next_llp = (dma_lli + ((idx + 1) * sizeof(struct \
							lli)));

			/* The last 2 bits encode the list master select. */
			next_llp = DMA_LLP_LMS(next_llp, DMA_LLP_AHBMASTER2);

			lli[idx].llp = cpu_to_le32(next_llp);
			idx++;
			sg_len -= len;
			addr += len;
		}
	}

	/*
	 * The last next ptr has to be zero and the last control low register
	 * has to have LLP_SRC_EN and LLP_DST_EN (linked list pointer source
	 * and destination enable) set back to 0 (disabled.) This is what tells
	 * the core that this is the last item in the linked list.
	 */
	if (idx) {
		lli[idx-1].llp = 0x00000000;
		lli[idx-1].ctl.low &= DMA_CTL_LLP_DISABLE_LE32;

		/* Flush cache to memory */
		dma_cache_sync(NULL, lli, (sizeof(struct lli) * idx),
			       DMA_BIDIRECTIONAL);
	}

	return idx;
}

/*
 * Function: dma_dwc_xfer_start
 * arguments: Channel number
 * Return : None
 * Enables the DMA channel
 */
static void dma_dwc_xfer_start(int dma_ch)
{
	/* Enable the DMA channel */
	out_le32(&(host_pvt.sata_dma_regs->dma_chan_en.low),
		 in_le32(&(host_pvt.sata_dma_regs->dma_chan_en.low)) |
		 DMA_ENABLE_CHAN(dma_ch));
}

static int dma_dwc_xfer_setup(struct scatterlist *sg, int num_elems,
			      struct lli *lli, dma_addr_t dma_lli,
			      void __iomem *addr, int dir)
{
	int dma_ch;
	int num_lli;
	/* Acquire DMA channel */
	dma_ch = dma_request_channel();
	if (dma_ch == -1) {
		dev_err(host_pvt.dwc_dev, "%s: dma channel unavailable\n",
			 __func__);
		return -EAGAIN;
	}

	/* Convert SG list to linked list of items (LLIs) for AHB DMA */
	num_lli = map_sg_to_lli(sg, num_elems, lli, dma_lli, addr, dir);

	dev_dbg(host_pvt.dwc_dev, "%s sg: 0x%p, count: %d lli: %p dma_lli:"
		" 0x%0xlx addr: %p lli count: %d\n", __func__, sg, num_elems,
		 lli, (u32)dma_lli, addr, num_lli);

	clear_chan_interrupts(dma_ch);

	/* Program the CFG register. */
	out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].cfg.high),
		 DMA_CFG_HW_HS_SRC(dma_ch) | DMA_CFG_HW_HS_DEST(dma_ch) |
		 DMA_CFG_PROTCTL | DMA_CFG_FCMOD_REQ);
	out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].cfg.low),
		 DMA_CFG_HW_CH_PRIOR(dma_ch));

	/* Program the address of the linked list */
	out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].llp.low),
		 DMA_LLP_LMS(dma_lli, DMA_LLP_AHBMASTER2));

	/* Program the CTL register with src enable / dst enable */
	out_le32(&(host_pvt.sata_dma_regs->chan_regs[dma_ch].ctl.low),
		 DMA_CTL_LLP_SRCEN | DMA_CTL_LLP_DSTEN);
	return dma_ch;
}

/*
 * Function: dma_dwc_exit
 * arguments: None
 * returns status
 * This function exits the SATA DMA driver
 */
static void dma_dwc_exit(struct sata_dwc_device *hsdev)
{
	dev_dbg(host_pvt.dwc_dev, "%s:\n", __func__);
	if (host_pvt.sata_dma_regs) {
		iounmap(host_pvt.sata_dma_regs);
		host_pvt.sata_dma_regs = NULL;
	}

	if (hsdev->irq_dma) {
		free_irq(hsdev->irq_dma, hsdev);
		hsdev->irq_dma = 0;
	}
}

/*
 * Function: dma_dwc_init
 * arguments: hsdev
 * returns status
 * This function initializes the SATA DMA driver
 */
static int dma_dwc_init(struct sata_dwc_device *hsdev, int irq)
{
	int err;

	err = dma_request_interrupts(hsdev, irq);
	if (err) {
		dev_err(host_pvt.dwc_dev, "%s: dma_request_interrupts returns"
			" %d\n", __func__, err);
		goto error_out;
	}

	/* Enabe DMA */
	out_le32(&(host_pvt.sata_dma_regs->dma_cfg.low), DMA_EN);

	dev_notice(host_pvt.dwc_dev, "DMA initialized\n");
	dev_dbg(host_pvt.dwc_dev, "SATA DMA registers=0x%p\n", host_pvt.\
		sata_dma_regs);

	return 0;

error_out:
	dma_dwc_exit(hsdev);

	return err;
}

static int sata_dwc_scr_read(struct ata_link *link, unsigned int scr, u32 *val)
{
	if (scr > SCR_NOTIFICATION) {
		dev_err(link->ap->dev, "%s: Incorrect SCR offset 0x%02x\n",
			__func__, scr);
		return -EINVAL;
	}

	*val = in_le32((void *)link->ap->ioaddr.scr_addr + (scr * 4));
	dev_dbg(link->ap->dev, "%s: id=%d reg=%d val=val=0x%08x\n",
		__func__, link->ap->print_id, scr, *val);

	return 0;
}

static int sata_dwc_scr_write(struct ata_link *link, unsigned int scr, u32 val)
{
	dev_dbg(link->ap->dev, "%s: id=%d reg=%d val=val=0x%08x\n",
		__func__, link->ap->print_id, scr, val);
	if (scr > SCR_NOTIFICATION) {
		dev_err(link->ap->dev, "%s: Incorrect SCR offset 0x%02x\n",
			 __func__, scr);
		return -EINVAL;
	}
	out_le32((void *)link->ap->ioaddr.scr_addr + (scr * 4), val);

	return 0;
}

static u32 core_scr_read(unsigned int scr)
{
	return in_le32((void __iomem *)(host_pvt.scr_addr_sstatus) +\
			(scr * 4));
}

static void core_scr_write(unsigned int scr, u32 val)
{
	out_le32((void __iomem *)(host_pvt.scr_addr_sstatus) + (scr * 4),
		val);
}

static void clear_serror(void)
{
	u32 val;
	val = core_scr_read(SCR_ERROR);
	core_scr_write(SCR_ERROR, val);

}

static void clear_interrupt_bit(struct sata_dwc_device *hsdev, u32 bit)
{
	out_le32(&hsdev->sata_dwc_regs->intpr,
		 in_le32(&hsdev->sata_dwc_regs->intpr));
}

static u32 qcmd_tag_to_mask(u8 tag)
{
	return 0x00000001 << (tag & 0x1f);
}

/* See ahci.c */
static void sata_dwc_error_intr(struct ata_port *ap,
				struct sata_dwc_device *hsdev, uint intpr)
{
	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
	struct ata_eh_info *ehi = &ap->link.eh_info;
	unsigned int err_mask = 0, action = 0;
	struct ata_queued_cmd *qc;
	u32 serror;
	u8 status, tag;
	u32 err_reg;

	ata_ehi_clear_desc(ehi);

	serror = core_scr_read(SCR_ERROR);
	status = ap->ops->sff_check_status(ap);

	err_reg = in_le32(&(host_pvt.sata_dma_regs->interrupt_status.error.\
			low));
	tag = ap->link.active_tag;

	dev_err(ap->dev, "%s SCR_ERROR=0x%08x intpr=0x%08x status=0x%08x "
		"dma_intp=%d pending=%d issued=%d dma_err_status=0x%08x\n",
		__func__, serror, intpr, status, host_pvt.dma_interrupt_count,
		hsdevp->dma_pending[tag], hsdevp->cmd_issued[tag], err_reg);

	/* Clear error register and interrupt bit */
	clear_serror();
	clear_interrupt_bit(hsdev, SATA_DWC_INTPR_ERR);

	/* This is the only error happening now.  TODO check for exact error */

	err_mask |= AC_ERR_HOST_BUS;
	action |= ATA_EH_RESET;

	/* Pass this on to EH */
	ehi->serror |= serror;
	ehi->action |= action;

	qc = ata_qc_from_tag(ap, tag);
	if (qc)
		qc->err_mask |= err_mask;
	else
		ehi->err_mask |= err_mask;

	ata_port_abort(ap);
}

/*
 * Function : sata_dwc_isr
 * arguments : irq, void *dev_instance, struct pt_regs *regs
 * Return value : irqreturn_t - status of IRQ
 * This Interrupt handler called via port ops registered function.
 * .irq_handler = sata_dwc_isr
 */
static irqreturn_t sata_dwc_isr(int irq, void *dev_instance)
{
	struct ata_host *host = (struct ata_host *)dev_instance;
	struct sata_dwc_device *hsdev = HSDEV_FROM_HOST(host);
	struct ata_port *ap;
	struct ata_queued_cmd *qc;
	unsigned long flags;
	u8 status, tag;
	int handled, num_processed, port = 0;
	uint intpr, sactive, sactive2, tag_mask;
	struct sata_dwc_device_port *hsdevp;
	host_pvt.sata_dwc_sactive_issued = 0;

	spin_lock_irqsave(&host->lock, flags);

	/* Read the interrupt register */
	intpr = in_le32(&hsdev->sata_dwc_regs->intpr);

	ap = host->ports[port];
	hsdevp = HSDEVP_FROM_AP(ap);

	dev_dbg(ap->dev, "%s intpr=0x%08x active_tag=%d\n", __func__, intpr,
		ap->link.active_tag);

	/* Check for error interrupt */
	if (intpr & SATA_DWC_INTPR_ERR) {
		sata_dwc_error_intr(ap, hsdev, intpr);
		handled = 1;
		goto DONE;
	}

	/* Check for DMA SETUP FIS (FP DMA) interrupt */
	if (intpr & SATA_DWC_INTPR_NEWFP) {
		clear_interrupt_bit(hsdev, SATA_DWC_INTPR_NEWFP);

		tag = (u8)(in_le32(&hsdev->sata_dwc_regs->fptagr));
		dev_dbg(ap->dev, "%s: NEWFP tag=%d\n", __func__, tag);
		if (hsdevp->cmd_issued[tag] != SATA_DWC_CMD_ISSUED_PEND)
			dev_warn(ap->dev, "CMD tag=%d not pending?\n", tag);

		host_pvt.sata_dwc_sactive_issued |= qcmd_tag_to_mask(tag);

		qc = ata_qc_from_tag(ap, tag);
		/*
		 * Start FP DMA for NCQ command.  At this point the tag is the
		 * active tag.  It is the tag that matches the command about to
		 * be completed.
		 */
		qc->ap->link.active_tag = tag;
		sata_dwc_bmdma_start_by_tag(qc, tag);

		handled = 1;
		goto DONE;
	}
	sactive = core_scr_read(SCR_ACTIVE);
	tag_mask = (host_pvt.sata_dwc_sactive_issued | sactive) ^ sactive;

	/* If no sactive issued and tag_mask is zero then this is not NCQ */
	if (host_pvt.sata_dwc_sactive_issued == 0 && tag_mask == 0) {
		if (ap->link.active_tag == ATA_TAG_POISON)
			tag = 0;
		else
			tag = ap->link.active_tag;
		qc = ata_qc_from_tag(ap, tag);

		/* DEV interrupt w/ no active qc? */
		if (unlikely(!qc || (qc->tf.flags & ATA_TFLAG_POLLING))) {
			dev_err(ap->dev, "%s interrupt with no active qc "
				"qc=%p\n", __func__, qc);
			ap->ops->sff_check_status(ap);
			handled = 1;
			goto DONE;
		}
		status = ap->ops->sff_check_status(ap);

		qc->ap->link.active_tag = tag;
		hsdevp->cmd_issued[tag] = SATA_DWC_CMD_ISSUED_NOT;

		if (status & ATA_ERR) {
			dev_dbg(ap->dev, "interrupt ATA_ERR (0x%x)\n", status);
			sata_dwc_qc_complete(ap, qc, 1);
			handled = 1;
			goto DONE;
		}

		dev_dbg(ap->dev, "%s non-NCQ cmd interrupt, protocol: %s\n",
			__func__, get_prot_descript(qc->tf.protocol));
DRVSTILLBUSY:
		if (ata_is_dma(qc->tf.protocol)) {
			/*
			 * Each DMA transaction produces 2 interrupts. The DMAC
			 * transfer complete interrupt and the SATA controller
			 * operation done interrupt. The command should be
			 * completed only after both interrupts are seen.
			 */
			host_pvt.dma_interrupt_count++;
			if (hsdevp->dma_pending[tag] == \
					SATA_DWC_DMA_PENDING_NONE) {
				dev_err(ap->dev, "%s: DMA not pending "
					"intpr=0x%08x status=0x%08x pending"
					"=%d\n", __func__, intpr, status,
					hsdevp->dma_pending[tag]);
			}

			if ((host_pvt.dma_interrupt_count % 2) == 0)
				sata_dwc_dma_xfer_complete(ap, 1);
		} else if (ata_is_pio(qc->tf.protocol)) {
			ata_sff_hsm_move(ap, qc, status, 0);
			handled = 1;
			goto DONE;
		} else {
			if (unlikely(sata_dwc_qc_complete(ap, qc, 1)))
				goto DRVSTILLBUSY;
		}

		handled = 1;
		goto DONE;
	}

	/*
	 * This is a NCQ command. At this point we need to figure out for which
	 * tags we have gotten a completion interrupt.  One interrupt may serve
	 * as completion for more than one operation when commands are queued
	 * (NCQ).  We need to process each completed command.
	 */

	 /* process completed commands */
	sactive = core_scr_read(SCR_ACTIVE);
	tag_mask = (host_pvt.sata_dwc_sactive_issued | sactive) ^ sactive;

	if (sactive != 0 || (host_pvt.sata_dwc_sactive_issued) > 1 || \
							tag_mask > 1) {
		dev_dbg(ap->dev, "%s NCQ:sactive=0x%08x  sactive_issued=0x%08x"
			"tag_mask=0x%08x\n", __func__, sactive,
			host_pvt.sata_dwc_sactive_issued, tag_mask);
	}

	if ((tag_mask | (host_pvt.sata_dwc_sactive_issued)) != \
					(host_pvt.sata_dwc_sactive_issued)) {
		dev_warn(ap->dev, "Bad tag mask?  sactive=0x%08x "
			 "(host_pvt.sata_dwc_sactive_issued)=0x%08x  tag_mask"
			 "=0x%08x\n", sactive, host_pvt.sata_dwc_sactive_issued,
			  tag_mask);
	}

	/* read just to clear ... not bad if currently still busy */
	status = ap->ops->sff_check_status(ap);
	dev_dbg(ap->dev, "%s ATA status register=0x%x\n", __func__, status);

	tag = 0;
	num_processed = 0;
	while (tag_mask) {
		num_processed++;
		while (!(tag_mask & 0x00000001)) {
			tag++;
			tag_mask <<= 1;
		}

		tag_mask &= (~0x00000001);
		qc = ata_qc_from_tag(ap, tag);

		/* To be picked up by completion functions */
		qc->ap->link.active_tag = tag;
		hsdevp->cmd_issued[tag] = SATA_DWC_CMD_ISSUED_NOT;

		/* Let libata/scsi layers handle error */
		if (status & ATA_ERR) {
			dev_dbg(ap->dev, "%s ATA_ERR (0x%x)\n", __func__,
				status);
			sata_dwc_qc_complete(ap, qc, 1);
			handled = 1;
			goto DONE;
		}

		/* Process completed command */
		dev_dbg(ap->dev, "%s NCQ command, protocol: %s\n", __func__,
			get_prot_descript(qc->tf.protocol));
		if (ata_is_dma(qc->tf.protocol)) {
			host_pvt.dma_interrupt_count++;
			if (hsdevp->dma_pending[tag] == \
					SATA_DWC_DMA_PENDING_NONE)
				dev_warn(ap->dev, "%s: DMA not pending?\n",
					__func__);
			if ((host_pvt.dma_interrupt_count % 2) == 0)
				sata_dwc_dma_xfer_complete(ap, 1);
		} else {
			if (unlikely(sata_dwc_qc_complete(ap, qc, 1)))
				goto STILLBUSY;
		}
		continue;

STILLBUSY:
		ap->stats.idle_irq++;
		dev_warn(ap->dev, "STILL BUSY IRQ ata%d: irq trap\n",
			ap->print_id);
	} /* while tag_mask */

	/*
	 * Check to see if any commands completed while we were processing our
	 * initial set of completed commands (read status clears interrupts,
	 * so we might miss a completed command interrupt if one came in while
	 * we were processing --we read status as part of processing a completed
	 * command).
	 */
	sactive2 = core_scr_read(SCR_ACTIVE);
	if (sactive2 != sactive) {
		dev_dbg(ap->dev, "More completed - sactive=0x%x sactive2"
			"=0x%x\n", sactive, sactive2);
	}
	handled = 1;

DONE:
	spin_unlock_irqrestore(&host->lock, flags);
	return IRQ_RETVAL(handled);
}

static void sata_dwc_clear_dmacr(struct sata_dwc_device_port *hsdevp, u8 tag)
{
	struct sata_dwc_device *hsdev = HSDEV_FROM_HSDEVP(hsdevp);

	if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_RX) {
		out_le32(&(hsdev->sata_dwc_regs->dmacr),
			 SATA_DWC_DMACR_RX_CLEAR(
				 in_le32(&(hsdev->sata_dwc_regs->dmacr))));
	} else if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_TX) {
		out_le32(&(hsdev->sata_dwc_regs->dmacr),
			 SATA_DWC_DMACR_TX_CLEAR(
				 in_le32(&(hsdev->sata_dwc_regs->dmacr))));
	} else {
		/*
		 * This should not happen, it indicates the driver is out of
		 * sync.  If it does happen, clear dmacr anyway.
		 */
		dev_err(host_pvt.dwc_dev, "%s DMA protocol RX and"
			"TX DMA not pending tag=0x%02x pending=%d"
			" dmacr: 0x%08x\n", __func__, tag,
			hsdevp->dma_pending[tag],
			in_le32(&(hsdev->sata_dwc_regs->dmacr)));
		out_le32(&(hsdev->sata_dwc_regs->dmacr),
			SATA_DWC_DMACR_TXRXCH_CLEAR);
	}
}

static void sata_dwc_dma_xfer_complete(struct ata_port *ap, u32 check_status)
{
	struct ata_queued_cmd *qc;
	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
	u8 tag = 0;

	tag = ap->link.active_tag;
	qc = ata_qc_from_tag(ap, tag);
	if (!qc) {
		dev_err(ap->dev, "failed to get qc");
		return;
	}

#ifdef DEBUG_NCQ
	if (tag > 0) {
		dev_info(ap->dev, "%s tag=%u cmd=0x%02x dma dir=%s proto=%s "
			 "dmacr=0x%08x\n", __func__, qc->tag, qc->tf.command,
			 get_dma_dir_descript(qc->dma_dir),
			 get_prot_descript(qc->tf.protocol),
			 in_le32(&(hsdev->sata_dwc_regs->dmacr)));
	}
#endif

	if (ata_is_dma(qc->tf.protocol)) {
		if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_NONE) {
			dev_err(ap->dev, "%s DMA protocol RX and TX DMA not "
				"pending dmacr: 0x%08x\n", __func__,
				in_le32(&(hsdev->sata_dwc_regs->dmacr)));
		}

		hsdevp->dma_pending[tag] = SATA_DWC_DMA_PENDING_NONE;
		sata_dwc_qc_complete(ap, qc, check_status);
		ap->link.active_tag = ATA_TAG_POISON;
	} else {
		sata_dwc_qc_complete(ap, qc, check_status);
	}
}

static int sata_dwc_qc_complete(struct ata_port *ap, struct ata_queued_cmd *qc,
				u32 check_status)
{
	u8 status = 0;
	u32 mask = 0x0;
	u8 tag = qc->tag;
	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
	host_pvt.sata_dwc_sactive_queued = 0;
	dev_dbg(ap->dev, "%s checkstatus? %x\n", __func__, check_status);

	if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_TX)
		dev_err(ap->dev, "TX DMA PENDING\n");
	else if (hsdevp->dma_pending[tag] == SATA_DWC_DMA_PENDING_RX)
		dev_err(ap->dev, "RX DMA PENDING\n");
	dev_dbg(ap->dev, "QC complete cmd=0x%02x status=0x%02x ata%u:"
		" protocol=%d\n", qc->tf.command, status, ap->print_id,
		 qc->tf.protocol);

	/* clear active bit */
	mask = (~(qcmd_tag_to_mask(tag)));
	host_pvt.sata_dwc_sactive_queued = (host_pvt.sata_dwc_sactive_queued) \
						& mask;
	host_pvt.sata_dwc_sactive_issued = (host_pvt.sata_dwc_sactive_issued) \
						& mask;
	ata_qc_complete(qc);
	return 0;
}

static void sata_dwc_enable_interrupts(struct sata_dwc_device *hsdev)
{
	/* Enable selective interrupts by setting the interrupt maskregister*/
	out_le32(&hsdev->sata_dwc_regs->intmr,
		 SATA_DWC_INTMR_ERRM |
		 SATA_DWC_INTMR_NEWFPM |
		 SATA_DWC_INTMR_PMABRTM |
		 SATA_DWC_INTMR_DMATM);
	/*
	 * Unmask the error bits that should trigger an error interrupt by
	 * setting the error mask register.
	 */
	out_le32(&hsdev->sata_dwc_regs->errmr, SATA_DWC_SERROR_ERR_BITS);

	dev_dbg(host_pvt.dwc_dev, "%s: INTMR = 0x%08x, ERRMR = 0x%08x\n",
		 __func__, in_le32(&hsdev->sata_dwc_regs->intmr),
		in_le32(&hsdev->sata_dwc_regs->errmr));
}

static void sata_dwc_setup_port(struct ata_ioports *port, unsigned long base)
{
	port->cmd_addr = (void *)base + 0x00;
	port->data_addr = (void *)base + 0x00;

	port->error_addr = (void *)base + 0x04;
	port->feature_addr = (void *)base + 0x04;

	port->nsect_addr = (void *)base + 0x08;

	port->lbal_addr = (void *)base + 0x0c;
	port->lbam_addr = (void *)base + 0x10;
	port->lbah_addr = (void *)base + 0x14;

	port->device_addr = (void *)base + 0x18;
	port->command_addr = (void *)base + 0x1c;
	port->status_addr = (void *)base + 0x1c;

	port->altstatus_addr = (void *)base + 0x20;
	port->ctl_addr = (void *)base + 0x20;
}

/*
 * Function : sata_dwc_port_start
 * arguments : struct ata_ioports *port
 * Return value : returns 0 if success, error code otherwise
 * This function allocates the scatter gather LLI table for AHB DMA
 */
static int sata_dwc_port_start(struct ata_port *ap)
{
	int err = 0;
	struct sata_dwc_device *hsdev;
	struct sata_dwc_device_port *hsdevp = NULL;
	struct device *pdev;
	int i;

	hsdev = HSDEV_FROM_AP(ap);

	dev_dbg(ap->dev, "%s: port_no=%d\n", __func__, ap->port_no);

	hsdev->host = ap->host;
	pdev = ap->host->dev;
	if (!pdev) {
		dev_err(ap->dev, "%s: no ap->host->dev\n", __func__);
		err = -ENODEV;
		goto CLEANUP;
	}

	/* Allocate Port Struct */
	hsdevp = kzalloc(sizeof(*hsdevp), GFP_KERNEL);
	if (!hsdevp) {
		dev_err(ap->dev, "%s: kmalloc failed for hsdevp\n", __func__);
		err = -ENOMEM;
		goto CLEANUP;
	}
	hsdevp->hsdev = hsdev;

	for (i = 0; i < SATA_DWC_QCMD_MAX; i++)
		hsdevp->cmd_issued[i] = SATA_DWC_CMD_ISSUED_NOT;

	ap->bmdma_prd = 0;	/* set these so libata doesn't use them */
	ap->bmdma_prd_dma = 0;

	/*
	 * DMA - Assign scatter gather LLI table. We can't use the libata
	 * version since it's PRD is IDE PCI specific.
	 */
	for (i = 0; i < SATA_DWC_QCMD_MAX; i++) {
		hsdevp->llit[i] = dma_alloc_coherent(pdev,
						     SATA_DWC_DMAC_LLI_TBL_SZ,
						     &(hsdevp->llit_dma[i]),
						     GFP_ATOMIC);
		if (!hsdevp->llit[i]) {
			dev_err(ap->dev, "%s: dma_alloc_coherent failed\n",
				 __func__);
			err = -ENOMEM;
			goto CLEANUP_ALLOC;
		}
	}

	if (ap->port_no == 0)  {
		dev_dbg(ap->dev, "%s: clearing TXCHEN, RXCHEN in DMAC\n",
			__func__);
		out_le32(&hsdev->sata_dwc_regs->dmacr,
			 SATA_DWC_DMACR_TXRXCH_CLEAR);

		dev_dbg(ap->dev, "%s: setting burst size in DBTSR\n",
			 __func__);
		out_le32(&hsdev->sata_dwc_regs->dbtsr,
			 (SATA_DWC_DBTSR_MWR(AHB_DMA_BRST_DFLT) |
			  SATA_DWC_DBTSR_MRD(AHB_DMA_BRST_DFLT)));
	}

	/* Clear any error bits before libata starts issuing commands */
	clear_serror();
	ap->private_data = hsdevp;
	dev_dbg(ap->dev, "%s: done\n", __func__);
	return 0;

CLEANUP_ALLOC:
	kfree(hsdevp);
CLEANUP:
	dev_dbg(ap->dev, "%s: fail. ap->id = %d\n", __func__, ap->print_id);
	return err;
}

static void sata_dwc_port_stop(struct ata_port *ap)
{
	int i;
	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);

	dev_dbg(ap->dev, "%s: ap->id = %d\n", __func__, ap->print_id);

	if (hsdevp && hsdev) {
		/* deallocate LLI table */
		for (i = 0; i < SATA_DWC_QCMD_MAX; i++) {
			dma_free_coherent(ap->host->dev,
					  SATA_DWC_DMAC_LLI_TBL_SZ,
					 hsdevp->llit[i], hsdevp->llit_dma[i]);
		}

		kfree(hsdevp);
	}
	ap->private_data = NULL;
}

/*
 * Function : sata_dwc_exec_command_by_tag
 * arguments : ata_port *ap, ata_taskfile *tf, u8 tag, u32 cmd_issued
 * Return value : None
 * This function keeps track of individual command tag ids and calls
 * ata_exec_command in libata
 */
static void sata_dwc_exec_command_by_tag(struct ata_port *ap,
					 struct ata_taskfile *tf,
					 u8 tag, u32 cmd_issued)
{
	unsigned long flags;
	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);

	dev_dbg(ap->dev, "%s cmd(0x%02x): %s tag=%d\n", __func__, tf->command,
		ata_get_cmd_descript(tf->command), tag);

	spin_lock_irqsave(&ap->host->lock, flags);
	hsdevp->cmd_issued[tag] = cmd_issued;
	spin_unlock_irqrestore(&ap->host->lock, flags);
	/*
	 * Clear SError before executing a new command.
	 * sata_dwc_scr_write and read can not be used here. Clearing the PM
	 * managed SError register for the disk needs to be done before the
	 * task file is loaded.
	 */
	clear_serror();
	ata_sff_exec_command(ap, tf);
}

static void sata_dwc_bmdma_setup_by_tag(struct ata_queued_cmd *qc, u8 tag)
{
	sata_dwc_exec_command_by_tag(qc->ap, &qc->tf, tag,
				     SATA_DWC_CMD_ISSUED_PEND);
}

static void sata_dwc_bmdma_setup(struct ata_queued_cmd *qc)
{
	u8 tag = qc->tag;

	if (ata_is_ncq(qc->tf.protocol)) {
		dev_dbg(qc->ap->dev, "%s: ap->link.sactive=0x%08x tag=%d\n",
			__func__, qc->ap->link.sactive, tag);
	} else {
		tag = 0;
	}
	sata_dwc_bmdma_setup_by_tag(qc, tag);
}

static void sata_dwc_bmdma_start_by_tag(struct ata_queued_cmd *qc, u8 tag)
{
	int start_dma;
	u32 reg, dma_chan;
	struct sata_dwc_device *hsdev = HSDEV_FROM_QC(qc);
	struct ata_port *ap = qc->ap;
	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);
	int dir = qc->dma_dir;
	dma_chan = hsdevp->dma_chan[tag];

	if (hsdevp->cmd_issued[tag] != SATA_DWC_CMD_ISSUED_NOT) {
		start_dma = 1;
		if (dir == DMA_TO_DEVICE)
			hsdevp->dma_pending[tag] = SATA_DWC_DMA_PENDING_TX;
		else
			hsdevp->dma_pending[tag] = SATA_DWC_DMA_PENDING_RX;
	} else {
		dev_err(ap->dev, "%s: Command not pending cmd_issued=%d "
			"(tag=%d) DMA NOT started\n", __func__,
			hsdevp->cmd_issued[tag], tag);
		start_dma = 0;
	}

	dev_dbg(ap->dev, "%s qc=%p tag: %x cmd: 0x%02x dma_dir: %s "
		"start_dma? %x\n", __func__, qc, tag, qc->tf.command,
		get_dma_dir_descript(qc->dma_dir), start_dma);
	sata_dwc_tf_dump(&(qc->tf));

	if (start_dma) {
		reg = core_scr_read(SCR_ERROR);
		if (reg & SATA_DWC_SERROR_ERR_BITS) {
			dev_err(ap->dev, "%s: ****** SError=0x%08x ******\n",
				__func__, reg);
		}

		if (dir == DMA_TO_DEVICE)
			out_le32(&hsdev->sata_dwc_regs->dmacr,
				SATA_DWC_DMACR_TXCHEN);
		else
			out_le32(&hsdev->sata_dwc_regs->dmacr,
				SATA_DWC_DMACR_RXCHEN);

		/* Enable AHB DMA transfer on the specified channel */
		dma_dwc_xfer_start(dma_chan);
	}
}

static void sata_dwc_bmdma_start(struct ata_queued_cmd *qc)
{
	u8 tag = qc->tag;

	if (ata_is_ncq(qc->tf.protocol)) {
		dev_dbg(qc->ap->dev, "%s: ap->link.sactive=0x%08x tag=%d\n",
			__func__, qc->ap->link.sactive, tag);
	} else {
		tag = 0;
	}
	dev_dbg(qc->ap->dev, "%s\n", __func__);
	sata_dwc_bmdma_start_by_tag(qc, tag);
}

/*
 * Function : sata_dwc_qc_prep_by_tag
 * arguments : ata_queued_cmd *qc, u8 tag
 * Return value : None
 * qc_prep for a particular queued command based on tag
 */
static void sata_dwc_qc_prep_by_tag(struct ata_queued_cmd *qc, u8 tag)
{
	struct scatterlist *sg = qc->sg;
	struct ata_port *ap = qc->ap;
	int dma_chan;
	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(ap);
	struct sata_dwc_device_port *hsdevp = HSDEVP_FROM_AP(ap);

	dev_dbg(ap->dev, "%s: port=%d dma dir=%s n_elem=%d\n",
		__func__, ap->port_no, get_dma_dir_descript(qc->dma_dir),
		 qc->n_elem);

	dma_chan = dma_dwc_xfer_setup(sg, qc->n_elem, hsdevp->llit[tag],
				      hsdevp->llit_dma[tag],
				      (void *__iomem)(&hsdev->sata_dwc_regs->\
				      dmadr), qc->dma_dir);
	if (dma_chan < 0) {
		dev_err(ap->dev, "%s: dma_dwc_xfer_setup returns err %d\n",
			__func__, dma_chan);
		return;
	}
	hsdevp->dma_chan[tag] = dma_chan;
}

static unsigned int sata_dwc_qc_issue(struct ata_queued_cmd *qc)
{
	u32 sactive;
	u8 tag = qc->tag;
	struct ata_port *ap = qc->ap;

#ifdef DEBUG_NCQ
	if (qc->tag > 0 || ap->link.sactive > 1)
		dev_info(ap->dev, "%s ap id=%d cmd(0x%02x)=%s qc tag=%d "
			 "prot=%s ap active_tag=0x%08x ap sactive=0x%08x\n",
			 __func__, ap->print_id, qc->tf.command,
			 ata_get_cmd_descript(qc->tf.command),
			 qc->tag, get_prot_descript(qc->tf.protocol),
			 ap->link.active_tag, ap->link.sactive);
#endif

	if (!ata_is_ncq(qc->tf.protocol))
		tag = 0;
	sata_dwc_qc_prep_by_tag(qc, tag);

	if (ata_is_ncq(qc->tf.protocol)) {
		sactive = core_scr_read(SCR_ACTIVE);
		sactive |= (0x00000001 << tag);
		core_scr_write(SCR_ACTIVE, sactive);

		dev_dbg(qc->ap->dev, "%s: tag=%d ap->link.sactive = 0x%08x "
			"sactive=0x%08x\n", __func__, tag, qc->ap->link.sactive,
			sactive);

		ap->ops->sff_tf_load(ap, &qc->tf);
		sata_dwc_exec_command_by_tag(ap, &qc->tf, qc->tag,
					     SATA_DWC_CMD_ISSUED_PEND);
	} else {
		ata_sff_qc_issue(qc);
	}
	return 0;
}

/*
 * Function : sata_dwc_qc_prep
 * arguments : ata_queued_cmd *qc
 * Return value : None
 * qc_prep for a particular queued command
 */

static void sata_dwc_qc_prep(struct ata_queued_cmd *qc)
{
	if ((qc->dma_dir == DMA_NONE) || (qc->tf.protocol == ATA_PROT_PIO))
		return;

#ifdef DEBUG_NCQ
	if (qc->tag > 0)
		dev_info(qc->ap->dev, "%s: qc->tag=%d ap->active_tag=0x%08x\n",
			 __func__, qc->tag, qc->ap->link.active_tag);

	return ;
#endif
}

static void sata_dwc_error_handler(struct ata_port *ap)
{
	ata_sff_error_handler(ap);
}

int sata_dwc_hardreset(struct ata_link *link, unsigned int *class,
			unsigned long deadline)
{
	struct sata_dwc_device *hsdev = HSDEV_FROM_AP(link->ap);
	int ret;

	ret = sata_sff_hardreset(link, class, deadline);

	sata_dwc_enable_interrupts(hsdev);

	/* Reconfigure the DMA control register */
	out_le32(&hsdev->sata_dwc_regs->dmacr,
		 SATA_DWC_DMACR_TXRXCH_CLEAR);

	/* Reconfigure the DMA Burst Transaction Size register */
	out_le32(&hsdev->sata_dwc_regs->dbtsr,
		 SATA_DWC_DBTSR_MWR(AHB_DMA_BRST_DFLT) |
		 SATA_DWC_DBTSR_MRD(AHB_DMA_BRST_DFLT));

	return ret;
}

/*
 * scsi mid-layer and libata interface structures
 */
static struct scsi_host_template sata_dwc_sht = {
	ATA_NCQ_SHT(DRV_NAME),
	/*
	 * test-only: Currently this driver doesn't handle NCQ
	 * correctly. We enable NCQ but set the queue depth to a
	 * max of 1. This will get fixed in in a future release.
	 */
	.sg_tablesize		= LIBATA_MAX_PRD,
	.can_queue		= ATA_DEF_QUEUE,	/* ATA_MAX_QUEUE */
	.dma_boundary		= ATA_DMA_BOUNDARY,
};

static struct ata_port_operations sata_dwc_ops = {
	.inherits		= &ata_sff_port_ops,

	.error_handler		= sata_dwc_error_handler,
	.hardreset		= sata_dwc_hardreset,

	.qc_prep		= sata_dwc_qc_prep,
	.qc_issue		= sata_dwc_qc_issue,

	.scr_read		= sata_dwc_scr_read,
	.scr_write		= sata_dwc_scr_write,

	.port_start		= sata_dwc_port_start,
	.port_stop		= sata_dwc_port_stop,

	.bmdma_setup		= sata_dwc_bmdma_setup,
	.bmdma_start		= sata_dwc_bmdma_start,
};

static const struct ata_port_info sata_dwc_port_info[] = {
	{
		.flags		= ATA_FLAG_SATA | ATA_FLAG_NCQ,
		.pio_mask	= ATA_PIO4,
		.udma_mask	= ATA_UDMA6,
		.port_ops	= &sata_dwc_ops,
	},
};

static int sata_dwc_probe(struct platform_device *ofdev)
{
	struct sata_dwc_device *hsdev;
	u32 idr, versionr;
	char *ver = (char *)&versionr;
	u8 *base = NULL;
	int err = 0;
	int irq, rc;
	struct ata_host *host;
	struct ata_port_info pi = sata_dwc_port_info[0];
	const struct ata_port_info *ppi[] = { &pi, NULL };
	struct device_node *np = ofdev->dev.of_node;
	u32 dma_chan;

	/* Allocate DWC SATA device */
	hsdev = kzalloc(sizeof(*hsdev), GFP_KERNEL);
	if (hsdev == NULL) {
		dev_err(&ofdev->dev, "kmalloc failed for hsdev\n");
		err = -ENOMEM;
		goto error;
	}

	if (of_property_read_u32(np, "dma-channel", &dma_chan)) {
		dev_warn(&ofdev->dev, "no dma-channel property set."
			 " Use channel 0\n");
		dma_chan = 0;
	}
	host_pvt.dma_channel = dma_chan;

	/* Ioremap SATA registers */
	base = of_iomap(ofdev->dev.of_node, 0);
	if (!base) {
		dev_err(&ofdev->dev, "ioremap failed for SATA register"
			" address\n");
		err = -ENODEV;
		goto error_kmalloc;
	}
	hsdev->reg_base = base;
	dev_dbg(&ofdev->dev, "ioremap done for SATA register address\n");

	/* Synopsys DWC SATA specific Registers */
	hsdev->sata_dwc_regs = (void *__iomem)(base + SATA_DWC_REG_OFFSET);

	/* Allocate and fill host */
	host = ata_host_alloc_pinfo(&ofdev->dev, ppi, SATA_DWC_MAX_PORTS);
	if (!host) {
		dev_err(&ofdev->dev, "ata_host_alloc_pinfo failed\n");
		err = -ENOMEM;
		goto error_iomap;
	}

	host->private_data = hsdev;

	/* Setup port */
	host->ports[0]->ioaddr.cmd_addr = base;
	host->ports[0]->ioaddr.scr_addr = base + SATA_DWC_SCR_OFFSET;
	host_pvt.scr_addr_sstatus = base + SATA_DWC_SCR_OFFSET;
	sata_dwc_setup_port(&host->ports[0]->ioaddr, (unsigned long)base);

	/* Read the ID and Version Registers */
	idr = in_le32(&hsdev->sata_dwc_regs->idr);
	versionr = in_le32(&hsdev->sata_dwc_regs->versionr);
	dev_notice(&ofdev->dev, "id %d, controller version %c.%c%c\n",
		   idr, ver[0], ver[1], ver[2]);

	/* Get SATA DMA interrupt number */
	irq = irq_of_parse_and_map(ofdev->dev.of_node, 1);
	if (irq == NO_IRQ) {
		dev_err(&ofdev->dev, "no SATA DMA irq\n");
		err = -ENODEV;
		goto error_out;
	}

	/* Get physical SATA DMA register base address */
	host_pvt.sata_dma_regs = of_iomap(ofdev->dev.of_node, 1);
	if (!(host_pvt.sata_dma_regs)) {
		dev_err(&ofdev->dev, "ioremap failed for AHBDMA register"
			" address\n");
		err = -ENODEV;
		goto error_out;
	}

	/* Save dev for later use in dev_xxx() routines */
	host_pvt.dwc_dev = &ofdev->dev;

	/* Initialize AHB DMAC */
	dma_dwc_init(hsdev, irq);

	/* Enable SATA Interrupts */
	sata_dwc_enable_interrupts(hsdev);

	/* Get SATA interrupt number */
	irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
	if (irq == NO_IRQ) {
		dev_err(&ofdev->dev, "no SATA DMA irq\n");
		err = -ENODEV;
		goto error_out;
	}

	/*
	 * Now, register with libATA core, this will also initiate the
	 * device discovery process, invoking our port_start() handler &
	 * error_handler() to execute a dummy Softreset EH session
	 */
	rc = ata_host_activate(host, irq, sata_dwc_isr, 0, &sata_dwc_sht);

	if (rc != 0)
		dev_err(&ofdev->dev, "failed to activate host");

	dev_set_drvdata(&ofdev->dev, host);
	return 0;

error_out:
	/* Free SATA DMA resources */
	dma_dwc_exit(hsdev);

error_iomap:
	iounmap(base);
error_kmalloc:
	kfree(hsdev);
error:
	return err;
}

static int sata_dwc_remove(struct platform_device *ofdev)
{
	struct device *dev = &ofdev->dev;
	struct ata_host *host = dev_get_drvdata(dev);
	struct sata_dwc_device *hsdev = host->private_data;

	ata_host_detach(host);
	dev_set_drvdata(dev, NULL);

	/* Free SATA DMA resources */
	dma_dwc_exit(hsdev);

	iounmap(hsdev->reg_base);
	kfree(hsdev);
	kfree(host);
	dev_dbg(&ofdev->dev, "done\n");
	return 0;
}

static const struct of_device_id sata_dwc_match[] = {
	{ .compatible = "amcc,sata-460ex", },
	{}
};
MODULE_DEVICE_TABLE(of, sata_dwc_match);

static struct platform_driver sata_dwc_driver = {
	.driver = {
		.name = DRV_NAME,
		.owner = THIS_MODULE,
		.of_match_table = sata_dwc_match,
	},
	.probe = sata_dwc_probe,
	.remove = sata_dwc_remove,
};

module_platform_driver(sata_dwc_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mark Miesfeld <mmiesfeld@amcc.com>");
MODULE_DESCRIPTION("DesignWare Cores SATA controller low lever driver");
MODULE_VERSION(DRV_VERSION);