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
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Driver for OHCI 1394 controllers
 *
 * Copyright (C) 2003-2006 Kristian Hoegsberg <krh@bitplanet.net>
 */

#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/compiler.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/firewire.h>
#include <linux/firewire-constants.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/mutex.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/time.h>
#include <linux/vmalloc.h>
#include <linux/workqueue.h>

#include <asm/byteorder.h>
#include <asm/page.h>

#ifdef CONFIG_PPC_PMAC
#include <asm/pmac_feature.h>
#endif

#include "core.h"
#include "ohci.h"

#define ohci_info(ohci, f, args...)	dev_info(ohci->card.device, f, ##args)
#define ohci_notice(ohci, f, args...)	dev_notice(ohci->card.device, f, ##args)
#define ohci_err(ohci, f, args...)	dev_err(ohci->card.device, f, ##args)

#define DESCRIPTOR_OUTPUT_MORE		0
#define DESCRIPTOR_OUTPUT_LAST		(1 << 12)
#define DESCRIPTOR_INPUT_MORE		(2 << 12)
#define DESCRIPTOR_INPUT_LAST		(3 << 12)
#define DESCRIPTOR_STATUS		(1 << 11)
#define DESCRIPTOR_KEY_IMMEDIATE	(2 << 8)
#define DESCRIPTOR_PING			(1 << 7)
#define DESCRIPTOR_YY			(1 << 6)
#define DESCRIPTOR_NO_IRQ		(0 << 4)
#define DESCRIPTOR_IRQ_ERROR		(1 << 4)
#define DESCRIPTOR_IRQ_ALWAYS		(3 << 4)
#define DESCRIPTOR_BRANCH_ALWAYS	(3 << 2)
#define DESCRIPTOR_WAIT			(3 << 0)

#define DESCRIPTOR_CMD			(0xf << 12)

struct descriptor {
	__le16 req_count;
	__le16 control;
	__le32 data_address;
	__le32 branch_address;
	__le16 res_count;
	__le16 transfer_status;
} __attribute__((aligned(16)));

#define CONTROL_SET(regs)	(regs)
#define CONTROL_CLEAR(regs)	((regs) + 4)
#define COMMAND_PTR(regs)	((regs) + 12)
#define CONTEXT_MATCH(regs)	((regs) + 16)

#define AR_BUFFER_SIZE	(32*1024)
#define AR_BUFFERS_MIN	DIV_ROUND_UP(AR_BUFFER_SIZE, PAGE_SIZE)
/* we need at least two pages for proper list management */
#define AR_BUFFERS	(AR_BUFFERS_MIN >= 2 ? AR_BUFFERS_MIN : 2)

#define MAX_ASYNC_PAYLOAD	4096
#define MAX_AR_PACKET_SIZE	(16 + MAX_ASYNC_PAYLOAD + 4)
#define AR_WRAPAROUND_PAGES	DIV_ROUND_UP(MAX_AR_PACKET_SIZE, PAGE_SIZE)

struct ar_context {
	struct fw_ohci *ohci;
	struct page *pages[AR_BUFFERS];
	void *buffer;
	struct descriptor *descriptors;
	dma_addr_t descriptors_bus;
	void *pointer;
	unsigned int last_buffer_index;
	u32 regs;
	struct tasklet_struct tasklet;
};

struct context;

typedef int (*descriptor_callback_t)(struct context *ctx,
				     struct descriptor *d,
				     struct descriptor *last);

/*
 * A buffer that contains a block of DMA-able coherent memory used for
 * storing a portion of a DMA descriptor program.
 */
struct descriptor_buffer {
	struct list_head list;
	dma_addr_t buffer_bus;
	size_t buffer_size;
	size_t used;
	struct descriptor buffer[];
};

struct context {
	struct fw_ohci *ohci;
	u32 regs;
	int total_allocation;
	u32 current_bus;
	bool running;
	bool flushing;

	/*
	 * List of page-sized buffers for storing DMA descriptors.
	 * Head of list contains buffers in use and tail of list contains
	 * free buffers.
	 */
	struct list_head buffer_list;

	/*
	 * Pointer to a buffer inside buffer_list that contains the tail
	 * end of the current DMA program.
	 */
	struct descriptor_buffer *buffer_tail;

	/*
	 * The descriptor containing the branch address of the first
	 * descriptor that has not yet been filled by the device.
	 */
	struct descriptor *last;

	/*
	 * The last descriptor block in the DMA program. It contains the branch
	 * address that must be updated upon appending a new descriptor.
	 */
	struct descriptor *prev;
	int prev_z;

	descriptor_callback_t callback;

	struct tasklet_struct tasklet;
};

#define IT_HEADER_SY(v)          ((v) <<  0)
#define IT_HEADER_TCODE(v)       ((v) <<  4)
#define IT_HEADER_CHANNEL(v)     ((v) <<  8)
#define IT_HEADER_TAG(v)         ((v) << 14)
#define IT_HEADER_SPEED(v)       ((v) << 16)
#define IT_HEADER_DATA_LENGTH(v) ((v) << 16)

struct iso_context {
	struct fw_iso_context base;
	struct context context;
	void *header;
	size_t header_length;
	unsigned long flushing_completions;
	u32 mc_buffer_bus;
	u16 mc_completed;
	u16 last_timestamp;
	u8 sync;
	u8 tags;
};

#define CONFIG_ROM_SIZE 1024

struct fw_ohci {
	struct fw_card card;

	__iomem char *registers;
	int node_id;
	int generation;
	int request_generation;	/* for timestamping incoming requests */
	unsigned quirks;
	unsigned int pri_req_max;
	u32 bus_time;
	bool bus_time_running;
	bool is_root;
	bool csr_state_setclear_abdicate;
	int n_ir;
	int n_it;
	/*
	 * Spinlock for accessing fw_ohci data.  Never call out of
	 * this driver with this lock held.
	 */
	spinlock_t lock;

	struct mutex phy_reg_mutex;

	void *misc_buffer;
	dma_addr_t misc_buffer_bus;

	struct ar_context ar_request_ctx;
	struct ar_context ar_response_ctx;
	struct context at_request_ctx;
	struct context at_response_ctx;

	u32 it_context_support;
	u32 it_context_mask;     /* unoccupied IT contexts */
	struct iso_context *it_context_list;
	u64 ir_context_channels; /* unoccupied channels */
	u32 ir_context_support;
	u32 ir_context_mask;     /* unoccupied IR contexts */
	struct iso_context *ir_context_list;
	u64 mc_channels; /* channels in use by the multichannel IR context */
	bool mc_allocated;

	__be32    *config_rom;
	dma_addr_t config_rom_bus;
	__be32    *next_config_rom;
	dma_addr_t next_config_rom_bus;
	__be32     next_header;

	__le32    *self_id;
	dma_addr_t self_id_bus;
	struct work_struct bus_reset_work;

	u32 self_id_buffer[512];
};

static struct workqueue_struct *selfid_workqueue;

static inline struct fw_ohci *fw_ohci(struct fw_card *card)
{
	return container_of(card, struct fw_ohci, card);
}

#define IT_CONTEXT_CYCLE_MATCH_ENABLE	0x80000000
#define IR_CONTEXT_BUFFER_FILL		0x80000000
#define IR_CONTEXT_ISOCH_HEADER		0x40000000
#define IR_CONTEXT_CYCLE_MATCH_ENABLE	0x20000000
#define IR_CONTEXT_MULTI_CHANNEL_MODE	0x10000000
#define IR_CONTEXT_DUAL_BUFFER_MODE	0x08000000

#define CONTEXT_RUN	0x8000
#define CONTEXT_WAKE	0x1000
#define CONTEXT_DEAD	0x0800
#define CONTEXT_ACTIVE	0x0400

#define OHCI1394_MAX_AT_REQ_RETRIES	0xf
#define OHCI1394_MAX_AT_RESP_RETRIES	0x2
#define OHCI1394_MAX_PHYS_RESP_RETRIES	0x8

#define OHCI1394_REGISTER_SIZE		0x800
#define OHCI1394_PCI_HCI_Control	0x40
#define SELF_ID_BUF_SIZE		0x800
#define OHCI_TCODE_PHY_PACKET		0x0e
#define OHCI_VERSION_1_1		0x010010

static char ohci_driver_name[] = KBUILD_MODNAME;

#define PCI_VENDOR_ID_PINNACLE_SYSTEMS	0x11bd
#define PCI_DEVICE_ID_AGERE_FW643	0x5901
#define PCI_DEVICE_ID_CREATIVE_SB1394	0x4001
#define PCI_DEVICE_ID_JMICRON_JMB38X_FW	0x2380
#define PCI_DEVICE_ID_TI_TSB12LV22	0x8009
#define PCI_DEVICE_ID_TI_TSB12LV26	0x8020
#define PCI_DEVICE_ID_TI_TSB82AA2	0x8025
#define PCI_DEVICE_ID_VIA_VT630X	0x3044
#define PCI_REV_ID_VIA_VT6306		0x46
#define PCI_DEVICE_ID_VIA_VT6315	0x3403

#define QUIRK_CYCLE_TIMER		0x1
#define QUIRK_RESET_PACKET		0x2
#define QUIRK_BE_HEADERS		0x4
#define QUIRK_NO_1394A			0x8
#define QUIRK_NO_MSI			0x10
#define QUIRK_TI_SLLZ059		0x20
#define QUIRK_IR_WAKE			0x40

// On PCI Express Root Complex in any type of AMD Ryzen machine, VIA VT6306/6307/6308 with Asmedia
// ASM1083/1085 brings an inconvenience that the read accesses to 'Isochronous Cycle Timer' register
// (at offset 0xf0 in PCI I/O space) often causes unexpected system reboot. The mechanism is not
// clear, since the read access to the other registers is enough safe; e.g. 'Node ID' register,
// while it is probable due to detection of any type of PCIe error.
#define QUIRK_REBOOT_BY_CYCLE_TIMER_READ	0x80000000

#if IS_ENABLED(CONFIG_X86)

static bool has_reboot_by_cycle_timer_read_quirk(const struct fw_ohci *ohci)
{
	return !!(ohci->quirks & QUIRK_REBOOT_BY_CYCLE_TIMER_READ);
}

#define PCI_DEVICE_ID_ASMEDIA_ASM108X	0x1080

static bool detect_vt630x_with_asm1083_on_amd_ryzen_machine(const struct pci_dev *pdev)
{
	const struct pci_dev *pcie_to_pci_bridge;

	// Detect any type of AMD Ryzen machine.
	if (!static_cpu_has(X86_FEATURE_ZEN))
		return false;

	// Detect VIA VT6306/6307/6308.
	if (pdev->vendor != PCI_VENDOR_ID_VIA)
		return false;
	if (pdev->device != PCI_DEVICE_ID_VIA_VT630X)
		return false;

	// Detect Asmedia ASM1083/1085.
	pcie_to_pci_bridge = pdev->bus->self;
	if (pcie_to_pci_bridge->vendor != PCI_VENDOR_ID_ASMEDIA)
		return false;
	if (pcie_to_pci_bridge->device != PCI_DEVICE_ID_ASMEDIA_ASM108X)
		return false;

	return true;
}

#else
#define has_reboot_by_cycle_timer_read_quirk(ohci) false
#define detect_vt630x_with_asm1083_on_amd_ryzen_machine(pdev)	false
#endif

/* In case of multiple matches in ohci_quirks[], only the first one is used. */
static const struct {
	unsigned short vendor, device, revision, flags;
} ohci_quirks[] = {
	{PCI_VENDOR_ID_AL, PCI_ANY_ID, PCI_ANY_ID,
		QUIRK_CYCLE_TIMER},

	{PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_FW, PCI_ANY_ID,
		QUIRK_BE_HEADERS},

	{PCI_VENDOR_ID_ATT, PCI_DEVICE_ID_AGERE_FW643, 6,
		QUIRK_NO_MSI},

	{PCI_VENDOR_ID_CREATIVE, PCI_DEVICE_ID_CREATIVE_SB1394, PCI_ANY_ID,
		QUIRK_RESET_PACKET},

	{PCI_VENDOR_ID_JMICRON, PCI_DEVICE_ID_JMICRON_JMB38X_FW, PCI_ANY_ID,
		QUIRK_NO_MSI},

	{PCI_VENDOR_ID_NEC, PCI_ANY_ID, PCI_ANY_ID,
		QUIRK_CYCLE_TIMER},

	{PCI_VENDOR_ID_O2, PCI_ANY_ID, PCI_ANY_ID,
		QUIRK_NO_MSI},

	{PCI_VENDOR_ID_RICOH, PCI_ANY_ID, PCI_ANY_ID,
		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},

	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV22, PCI_ANY_ID,
		QUIRK_CYCLE_TIMER | QUIRK_RESET_PACKET | QUIRK_NO_1394A},

	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB12LV26, PCI_ANY_ID,
		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},

	{PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_TSB82AA2, PCI_ANY_ID,
		QUIRK_RESET_PACKET | QUIRK_TI_SLLZ059},

	{PCI_VENDOR_ID_TI, PCI_ANY_ID, PCI_ANY_ID,
		QUIRK_RESET_PACKET},

	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT630X, PCI_REV_ID_VIA_VT6306,
		QUIRK_CYCLE_TIMER | QUIRK_IR_WAKE},

	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT6315, 0,
		QUIRK_CYCLE_TIMER /* FIXME: necessary? */ | QUIRK_NO_MSI},

	{PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VT6315, PCI_ANY_ID,
		QUIRK_NO_MSI},

	{PCI_VENDOR_ID_VIA, PCI_ANY_ID, PCI_ANY_ID,
		QUIRK_CYCLE_TIMER | QUIRK_NO_MSI},
};

/* This overrides anything that was found in ohci_quirks[]. */
static int param_quirks;
module_param_named(quirks, param_quirks, int, 0644);
MODULE_PARM_DESC(quirks, "Chip quirks (default = 0"
	", nonatomic cycle timer = "	__stringify(QUIRK_CYCLE_TIMER)
	", reset packet generation = "	__stringify(QUIRK_RESET_PACKET)
	", AR/selfID endianness = "	__stringify(QUIRK_BE_HEADERS)
	", no 1394a enhancements = "	__stringify(QUIRK_NO_1394A)
	", disable MSI = "		__stringify(QUIRK_NO_MSI)
	", TI SLLZ059 erratum = "	__stringify(QUIRK_TI_SLLZ059)
	", IR wake unreliable = "	__stringify(QUIRK_IR_WAKE)
	")");

#define OHCI_PARAM_DEBUG_AT_AR		1
#define OHCI_PARAM_DEBUG_SELFIDS	2
#define OHCI_PARAM_DEBUG_IRQS		4
#define OHCI_PARAM_DEBUG_BUSRESETS	8 /* only effective before chip init */

static int param_debug;
module_param_named(debug, param_debug, int, 0644);
MODULE_PARM_DESC(debug, "Verbose logging (default = 0"
	", AT/AR events = "	__stringify(OHCI_PARAM_DEBUG_AT_AR)
	", self-IDs = "		__stringify(OHCI_PARAM_DEBUG_SELFIDS)
	", IRQs = "		__stringify(OHCI_PARAM_DEBUG_IRQS)
	", busReset events = "	__stringify(OHCI_PARAM_DEBUG_BUSRESETS)
	", or a combination, or all = -1)");

static bool param_remote_dma;
module_param_named(remote_dma, param_remote_dma, bool, 0444);
MODULE_PARM_DESC(remote_dma, "Enable unfiltered remote DMA (default = N)");

static void log_irqs(struct fw_ohci *ohci, u32 evt)
{
	if (likely(!(param_debug &
			(OHCI_PARAM_DEBUG_IRQS | OHCI_PARAM_DEBUG_BUSRESETS))))
		return;

	if (!(param_debug & OHCI_PARAM_DEBUG_IRQS) &&
	    !(evt & OHCI1394_busReset))
		return;

	ohci_notice(ohci, "IRQ %08x%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s\n", evt,
	    evt & OHCI1394_selfIDComplete	? " selfID"		: "",
	    evt & OHCI1394_RQPkt		? " AR_req"		: "",
	    evt & OHCI1394_RSPkt		? " AR_resp"		: "",
	    evt & OHCI1394_reqTxComplete	? " AT_req"		: "",
	    evt & OHCI1394_respTxComplete	? " AT_resp"		: "",
	    evt & OHCI1394_isochRx		? " IR"			: "",
	    evt & OHCI1394_isochTx		? " IT"			: "",
	    evt & OHCI1394_postedWriteErr	? " postedWriteErr"	: "",
	    evt & OHCI1394_cycleTooLong		? " cycleTooLong"	: "",
	    evt & OHCI1394_cycle64Seconds	? " cycle64Seconds"	: "",
	    evt & OHCI1394_cycleInconsistent	? " cycleInconsistent"	: "",
	    evt & OHCI1394_regAccessFail	? " regAccessFail"	: "",
	    evt & OHCI1394_unrecoverableError	? " unrecoverableError"	: "",
	    evt & OHCI1394_busReset		? " busReset"		: "",
	    evt & ~(OHCI1394_selfIDComplete | OHCI1394_RQPkt |
		    OHCI1394_RSPkt | OHCI1394_reqTxComplete |
		    OHCI1394_respTxComplete | OHCI1394_isochRx |
		    OHCI1394_isochTx | OHCI1394_postedWriteErr |
		    OHCI1394_cycleTooLong | OHCI1394_cycle64Seconds |
		    OHCI1394_cycleInconsistent |
		    OHCI1394_regAccessFail | OHCI1394_busReset)
						? " ?"			: "");
}

static const char *speed[] = {
	[0] = "S100", [1] = "S200", [2] = "S400",    [3] = "beta",
};
static const char *power[] = {
	[0] = "+0W",  [1] = "+15W", [2] = "+30W",    [3] = "+45W",
	[4] = "-3W",  [5] = " ?W",  [6] = "-3..-6W", [7] = "-3..-10W",
};
static const char port[] = { '.', '-', 'p', 'c', };

static char _p(u32 *s, int shift)
{
	return port[*s >> shift & 3];
}

static void log_selfids(struct fw_ohci *ohci, int generation, int self_id_count)
{
	u32 *s;

	if (likely(!(param_debug & OHCI_PARAM_DEBUG_SELFIDS)))
		return;

	ohci_notice(ohci, "%d selfIDs, generation %d, local node ID %04x\n",
		    self_id_count, generation, ohci->node_id);

	for (s = ohci->self_id_buffer; self_id_count--; ++s)
		if ((*s & 1 << 23) == 0)
			ohci_notice(ohci,
			    "selfID 0: %08x, phy %d [%c%c%c] %s gc=%d %s %s%s%s\n",
			    *s, *s >> 24 & 63, _p(s, 6), _p(s, 4), _p(s, 2),
			    speed[*s >> 14 & 3], *s >> 16 & 63,
			    power[*s >> 8 & 7], *s >> 22 & 1 ? "L" : "",
			    *s >> 11 & 1 ? "c" : "", *s & 2 ? "i" : "");
		else
			ohci_notice(ohci,
			    "selfID n: %08x, phy %d [%c%c%c%c%c%c%c%c]\n",
			    *s, *s >> 24 & 63,
			    _p(s, 16), _p(s, 14), _p(s, 12), _p(s, 10),
			    _p(s,  8), _p(s,  6), _p(s,  4), _p(s,  2));
}

static const char *evts[] = {
	[0x00] = "evt_no_status",	[0x01] = "-reserved-",
	[0x02] = "evt_long_packet",	[0x03] = "evt_missing_ack",
	[0x04] = "evt_underrun",	[0x05] = "evt_overrun",
	[0x06] = "evt_descriptor_read",	[0x07] = "evt_data_read",
	[0x08] = "evt_data_write",	[0x09] = "evt_bus_reset",
	[0x0a] = "evt_timeout",		[0x0b] = "evt_tcode_err",
	[0x0c] = "-reserved-",		[0x0d] = "-reserved-",
	[0x0e] = "evt_unknown",		[0x0f] = "evt_flushed",
	[0x10] = "-reserved-",		[0x11] = "ack_complete",
	[0x12] = "ack_pending ",	[0x13] = "-reserved-",
	[0x14] = "ack_busy_X",		[0x15] = "ack_busy_A",
	[0x16] = "ack_busy_B",		[0x17] = "-reserved-",
	[0x18] = "-reserved-",		[0x19] = "-reserved-",
	[0x1a] = "-reserved-",		[0x1b] = "ack_tardy",
	[0x1c] = "-reserved-",		[0x1d] = "ack_data_error",
	[0x1e] = "ack_type_error",	[0x1f] = "-reserved-",
	[0x20] = "pending/cancelled",
};
static const char *tcodes[] = {
	[0x0] = "QW req",		[0x1] = "BW req",
	[0x2] = "W resp",		[0x3] = "-reserved-",
	[0x4] = "QR req",		[0x5] = "BR req",
	[0x6] = "QR resp",		[0x7] = "BR resp",
	[0x8] = "cycle start",		[0x9] = "Lk req",
	[0xa] = "async stream packet",	[0xb] = "Lk resp",
	[0xc] = "-reserved-",		[0xd] = "-reserved-",
	[0xe] = "link internal",	[0xf] = "-reserved-",
};

static void log_ar_at_event(struct fw_ohci *ohci,
			    char dir, int speed, u32 *header, int evt)
{
	int tcode = header[0] >> 4 & 0xf;
	char specific[12];

	if (likely(!(param_debug & OHCI_PARAM_DEBUG_AT_AR)))
		return;

	if (unlikely(evt >= ARRAY_SIZE(evts)))
			evt = 0x1f;

	if (evt == OHCI1394_evt_bus_reset) {
		ohci_notice(ohci, "A%c evt_bus_reset, generation %d\n",
			    dir, (header[2] >> 16) & 0xff);
		return;
	}

	switch (tcode) {
	case 0x0: case 0x6: case 0x8:
		snprintf(specific, sizeof(specific), " = %08x",
			 be32_to_cpu((__force __be32)header[3]));
		break;
	case 0x1: case 0x5: case 0x7: case 0x9: case 0xb:
		snprintf(specific, sizeof(specific), " %x,%x",
			 header[3] >> 16, header[3] & 0xffff);
		break;
	default:
		specific[0] = '\0';
	}

	switch (tcode) {
	case 0xa:
		ohci_notice(ohci, "A%c %s, %s\n",
			    dir, evts[evt], tcodes[tcode]);
		break;
	case 0xe:
		ohci_notice(ohci, "A%c %s, PHY %08x %08x\n",
			    dir, evts[evt], header[1], header[2]);
		break;
	case 0x0: case 0x1: case 0x4: case 0x5: case 0x9:
		ohci_notice(ohci,
			    "A%c spd %x tl %02x, %04x -> %04x, %s, %s, %04x%08x%s\n",
			    dir, speed, header[0] >> 10 & 0x3f,
			    header[1] >> 16, header[0] >> 16, evts[evt],
			    tcodes[tcode], header[1] & 0xffff, header[2], specific);
		break;
	default:
		ohci_notice(ohci,
			    "A%c spd %x tl %02x, %04x -> %04x, %s, %s%s\n",
			    dir, speed, header[0] >> 10 & 0x3f,
			    header[1] >> 16, header[0] >> 16, evts[evt],
			    tcodes[tcode], specific);
	}
}

static inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
{
	writel(data, ohci->registers + offset);
}

static inline u32 reg_read(const struct fw_ohci *ohci, int offset)
{
	return readl(ohci->registers + offset);
}

static inline void flush_writes(const struct fw_ohci *ohci)
{
	/* Do a dummy read to flush writes. */
	reg_read(ohci, OHCI1394_Version);
}

/*
 * Beware!  read_phy_reg(), write_phy_reg(), update_phy_reg(), and
 * read_paged_phy_reg() require the caller to hold ohci->phy_reg_mutex.
 * In other words, only use ohci_read_phy_reg() and ohci_update_phy_reg()
 * directly.  Exceptions are intrinsically serialized contexts like pci_probe.
 */
static int read_phy_reg(struct fw_ohci *ohci, int addr)
{
	u32 val;
	int i;

	reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
	for (i = 0; i < 3 + 100; i++) {
		val = reg_read(ohci, OHCI1394_PhyControl);
		if (!~val)
			return -ENODEV; /* Card was ejected. */

		if (val & OHCI1394_PhyControl_ReadDone)
			return OHCI1394_PhyControl_ReadData(val);

		/*
		 * Try a few times without waiting.  Sleeping is necessary
		 * only when the link/PHY interface is busy.
		 */
		if (i >= 3)
			msleep(1);
	}
	ohci_err(ohci, "failed to read phy reg %d\n", addr);
	dump_stack();

	return -EBUSY;
}

static int write_phy_reg(const struct fw_ohci *ohci, int addr, u32 val)
{
	int i;

	reg_write(ohci, OHCI1394_PhyControl,
		  OHCI1394_PhyControl_Write(addr, val));
	for (i = 0; i < 3 + 100; i++) {
		val = reg_read(ohci, OHCI1394_PhyControl);
		if (!~val)
			return -ENODEV; /* Card was ejected. */

		if (!(val & OHCI1394_PhyControl_WritePending))
			return 0;

		if (i >= 3)
			msleep(1);
	}
	ohci_err(ohci, "failed to write phy reg %d, val %u\n", addr, val);
	dump_stack();

	return -EBUSY;
}

static int update_phy_reg(struct fw_ohci *ohci, int addr,
			  int clear_bits, int set_bits)
{
	int ret = read_phy_reg(ohci, addr);
	if (ret < 0)
		return ret;

	/*
	 * The interrupt status bits are cleared by writing a one bit.
	 * Avoid clearing them unless explicitly requested in set_bits.
	 */
	if (addr == 5)
		clear_bits |= PHY_INT_STATUS_BITS;

	return write_phy_reg(ohci, addr, (ret & ~clear_bits) | set_bits);
}

static int read_paged_phy_reg(struct fw_ohci *ohci, int page, int addr)
{
	int ret;

	ret = update_phy_reg(ohci, 7, PHY_PAGE_SELECT, page << 5);
	if (ret < 0)
		return ret;

	return read_phy_reg(ohci, addr);
}

static int ohci_read_phy_reg(struct fw_card *card, int addr)
{
	struct fw_ohci *ohci = fw_ohci(card);
	int ret;

	mutex_lock(&ohci->phy_reg_mutex);
	ret = read_phy_reg(ohci, addr);
	mutex_unlock(&ohci->phy_reg_mutex);

	return ret;
}

static int ohci_update_phy_reg(struct fw_card *card, int addr,
			       int clear_bits, int set_bits)
{
	struct fw_ohci *ohci = fw_ohci(card);
	int ret;

	mutex_lock(&ohci->phy_reg_mutex);
	ret = update_phy_reg(ohci, addr, clear_bits, set_bits);
	mutex_unlock(&ohci->phy_reg_mutex);

	return ret;
}

static inline dma_addr_t ar_buffer_bus(struct ar_context *ctx, unsigned int i)
{
	return page_private(ctx->pages[i]);
}

static void ar_context_link_page(struct ar_context *ctx, unsigned int index)
{
	struct descriptor *d;

	d = &ctx->descriptors[index];
	d->branch_address  &= cpu_to_le32(~0xf);
	d->res_count       =  cpu_to_le16(PAGE_SIZE);
	d->transfer_status =  0;

	wmb(); /* finish init of new descriptors before branch_address update */
	d = &ctx->descriptors[ctx->last_buffer_index];
	d->branch_address  |= cpu_to_le32(1);

	ctx->last_buffer_index = index;

	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
}

static void ar_context_release(struct ar_context *ctx)
{
	struct device *dev = ctx->ohci->card.device;
	unsigned int i;

	if (!ctx->buffer)
		return;

	vunmap(ctx->buffer);

	for (i = 0; i < AR_BUFFERS; i++) {
		if (ctx->pages[i])
			dma_free_pages(dev, PAGE_SIZE, ctx->pages[i],
				       ar_buffer_bus(ctx, i), DMA_FROM_DEVICE);
	}
}

static void ar_context_abort(struct ar_context *ctx, const char *error_msg)
{
	struct fw_ohci *ohci = ctx->ohci;

	if (reg_read(ohci, CONTROL_CLEAR(ctx->regs)) & CONTEXT_RUN) {
		reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
		flush_writes(ohci);

		ohci_err(ohci, "AR error: %s; DMA stopped\n", error_msg);
	}
	/* FIXME: restart? */
}

static inline unsigned int ar_next_buffer_index(unsigned int index)
{
	return (index + 1) % AR_BUFFERS;
}

static inline unsigned int ar_first_buffer_index(struct ar_context *ctx)
{
	return ar_next_buffer_index(ctx->last_buffer_index);
}

/*
 * We search for the buffer that contains the last AR packet DMA data written
 * by the controller.
 */
static unsigned int ar_search_last_active_buffer(struct ar_context *ctx,
						 unsigned int *buffer_offset)
{
	unsigned int i, next_i, last = ctx->last_buffer_index;
	__le16 res_count, next_res_count;

	i = ar_first_buffer_index(ctx);
	res_count = READ_ONCE(ctx->descriptors[i].res_count);

	/* A buffer that is not yet completely filled must be the last one. */
	while (i != last && res_count == 0) {

		/* Peek at the next descriptor. */
		next_i = ar_next_buffer_index(i);
		rmb(); /* read descriptors in order */
		next_res_count = READ_ONCE(ctx->descriptors[next_i].res_count);
		/*
		 * If the next descriptor is still empty, we must stop at this
		 * descriptor.
		 */
		if (next_res_count == cpu_to_le16(PAGE_SIZE)) {
			/*
			 * The exception is when the DMA data for one packet is
			 * split over three buffers; in this case, the middle
			 * buffer's descriptor might be never updated by the
			 * controller and look still empty, and we have to peek
			 * at the third one.
			 */
			if (MAX_AR_PACKET_SIZE > PAGE_SIZE && i != last) {
				next_i = ar_next_buffer_index(next_i);
				rmb();
				next_res_count = READ_ONCE(ctx->descriptors[next_i].res_count);
				if (next_res_count != cpu_to_le16(PAGE_SIZE))
					goto next_buffer_is_active;
			}

			break;
		}

next_buffer_is_active:
		i = next_i;
		res_count = next_res_count;
	}

	rmb(); /* read res_count before the DMA data */

	*buffer_offset = PAGE_SIZE - le16_to_cpu(res_count);
	if (*buffer_offset > PAGE_SIZE) {
		*buffer_offset = 0;
		ar_context_abort(ctx, "corrupted descriptor");
	}

	return i;
}

static void ar_sync_buffers_for_cpu(struct ar_context *ctx,
				    unsigned int end_buffer_index,
				    unsigned int end_buffer_offset)
{
	unsigned int i;

	i = ar_first_buffer_index(ctx);
	while (i != end_buffer_index) {
		dma_sync_single_for_cpu(ctx->ohci->card.device,
					ar_buffer_bus(ctx, i),
					PAGE_SIZE, DMA_FROM_DEVICE);
		i = ar_next_buffer_index(i);
	}
	if (end_buffer_offset > 0)
		dma_sync_single_for_cpu(ctx->ohci->card.device,
					ar_buffer_bus(ctx, i),
					end_buffer_offset, DMA_FROM_DEVICE);
}

#if defined(CONFIG_PPC_PMAC) && defined(CONFIG_PPC32)
#define cond_le32_to_cpu(v) \
	(ohci->quirks & QUIRK_BE_HEADERS ? (__force __u32)(v) : le32_to_cpu(v))
#else
#define cond_le32_to_cpu(v) le32_to_cpu(v)
#endif

static __le32 *handle_ar_packet(struct ar_context *ctx, __le32 *buffer)
{
	struct fw_ohci *ohci = ctx->ohci;
	struct fw_packet p;
	u32 status, length, tcode;
	int evt;

	p.header[0] = cond_le32_to_cpu(buffer[0]);
	p.header[1] = cond_le32_to_cpu(buffer[1]);
	p.header[2] = cond_le32_to_cpu(buffer[2]);

	tcode = (p.header[0] >> 4) & 0x0f;
	switch (tcode) {
	case TCODE_WRITE_QUADLET_REQUEST:
	case TCODE_READ_QUADLET_RESPONSE:
		p.header[3] = (__force __u32) buffer[3];
		p.header_length = 16;
		p.payload_length = 0;
		break;

	case TCODE_READ_BLOCK_REQUEST :
		p.header[3] = cond_le32_to_cpu(buffer[3]);
		p.header_length = 16;
		p.payload_length = 0;
		break;

	case TCODE_WRITE_BLOCK_REQUEST:
	case TCODE_READ_BLOCK_RESPONSE:
	case TCODE_LOCK_REQUEST:
	case TCODE_LOCK_RESPONSE:
		p.header[3] = cond_le32_to_cpu(buffer[3]);
		p.header_length = 16;
		p.payload_length = p.header[3] >> 16;
		if (p.payload_length > MAX_ASYNC_PAYLOAD) {
			ar_context_abort(ctx, "invalid packet length");
			return NULL;
		}
		break;

	case TCODE_WRITE_RESPONSE:
	case TCODE_READ_QUADLET_REQUEST:
	case OHCI_TCODE_PHY_PACKET:
		p.header_length = 12;
		p.payload_length = 0;
		break;

	default:
		ar_context_abort(ctx, "invalid tcode");
		return NULL;
	}

	p.payload = (void *) buffer + p.header_length;

	/* FIXME: What to do about evt_* errors? */
	length = (p.header_length + p.payload_length + 3) / 4;
	status = cond_le32_to_cpu(buffer[length]);
	evt    = (status >> 16) & 0x1f;

	p.ack        = evt - 16;
	p.speed      = (status >> 21) & 0x7;
	p.timestamp  = status & 0xffff;
	p.generation = ohci->request_generation;

	log_ar_at_event(ohci, 'R', p.speed, p.header, evt);

	/*
	 * Several controllers, notably from NEC and VIA, forget to
	 * write ack_complete status at PHY packet reception.
	 */
	if (evt == OHCI1394_evt_no_status &&
	    (p.header[0] & 0xff) == (OHCI1394_phy_tcode << 4))
		p.ack = ACK_COMPLETE;

	/*
	 * The OHCI bus reset handler synthesizes a PHY packet with
	 * the new generation number when a bus reset happens (see
	 * section 8.4.2.3).  This helps us determine when a request
	 * was received and make sure we send the response in the same
	 * generation.  We only need this for requests; for responses
	 * we use the unique tlabel for finding the matching
	 * request.
	 *
	 * Alas some chips sometimes emit bus reset packets with a
	 * wrong generation.  We set the correct generation for these
	 * at a slightly incorrect time (in bus_reset_work).
	 */
	if (evt == OHCI1394_evt_bus_reset) {
		if (!(ohci->quirks & QUIRK_RESET_PACKET))
			ohci->request_generation = (p.header[2] >> 16) & 0xff;
	} else if (ctx == &ohci->ar_request_ctx) {
		fw_core_handle_request(&ohci->card, &p);
	} else {
		fw_core_handle_response(&ohci->card, &p);
	}

	return buffer + length + 1;
}

static void *handle_ar_packets(struct ar_context *ctx, void *p, void *end)
{
	void *next;

	while (p < end) {
		next = handle_ar_packet(ctx, p);
		if (!next)
			return p;
		p = next;
	}

	return p;
}

static void ar_recycle_buffers(struct ar_context *ctx, unsigned int end_buffer)
{
	unsigned int i;

	i = ar_first_buffer_index(ctx);
	while (i != end_buffer) {
		dma_sync_single_for_device(ctx->ohci->card.device,
					   ar_buffer_bus(ctx, i),
					   PAGE_SIZE, DMA_FROM_DEVICE);
		ar_context_link_page(ctx, i);
		i = ar_next_buffer_index(i);
	}
}

static void ar_context_tasklet(unsigned long data)
{
	struct ar_context *ctx = (struct ar_context *)data;
	unsigned int end_buffer_index, end_buffer_offset;
	void *p, *end;

	p = ctx->pointer;
	if (!p)
		return;

	end_buffer_index = ar_search_last_active_buffer(ctx,
							&end_buffer_offset);
	ar_sync_buffers_for_cpu(ctx, end_buffer_index, end_buffer_offset);
	end = ctx->buffer + end_buffer_index * PAGE_SIZE + end_buffer_offset;

	if (end_buffer_index < ar_first_buffer_index(ctx)) {
		/*
		 * The filled part of the overall buffer wraps around; handle
		 * all packets up to the buffer end here.  If the last packet
		 * wraps around, its tail will be visible after the buffer end
		 * because the buffer start pages are mapped there again.
		 */
		void *buffer_end = ctx->buffer + AR_BUFFERS * PAGE_SIZE;
		p = handle_ar_packets(ctx, p, buffer_end);
		if (p < buffer_end)
			goto error;
		/* adjust p to point back into the actual buffer */
		p -= AR_BUFFERS * PAGE_SIZE;
	}

	p = handle_ar_packets(ctx, p, end);
	if (p != end) {
		if (p > end)
			ar_context_abort(ctx, "inconsistent descriptor");
		goto error;
	}

	ctx->pointer = p;
	ar_recycle_buffers(ctx, end_buffer_index);

	return;

error:
	ctx->pointer = NULL;
}

static int ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci,
			   unsigned int descriptors_offset, u32 regs)
{
	struct device *dev = ohci->card.device;
	unsigned int i;
	dma_addr_t dma_addr;
	struct page *pages[AR_BUFFERS + AR_WRAPAROUND_PAGES];
	struct descriptor *d;

	ctx->regs        = regs;
	ctx->ohci        = ohci;
	tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);

	for (i = 0; i < AR_BUFFERS; i++) {
		ctx->pages[i] = dma_alloc_pages(dev, PAGE_SIZE, &dma_addr,
						DMA_FROM_DEVICE, GFP_KERNEL);
		if (!ctx->pages[i])
			goto out_of_memory;
		set_page_private(ctx->pages[i], dma_addr);
		dma_sync_single_for_device(dev, dma_addr, PAGE_SIZE,
					   DMA_FROM_DEVICE);
	}

	for (i = 0; i < AR_BUFFERS; i++)
		pages[i]              = ctx->pages[i];
	for (i = 0; i < AR_WRAPAROUND_PAGES; i++)
		pages[AR_BUFFERS + i] = ctx->pages[i];
	ctx->buffer = vmap(pages, ARRAY_SIZE(pages), VM_MAP, PAGE_KERNEL);
	if (!ctx->buffer)
		goto out_of_memory;

	ctx->descriptors     = ohci->misc_buffer     + descriptors_offset;
	ctx->descriptors_bus = ohci->misc_buffer_bus + descriptors_offset;

	for (i = 0; i < AR_BUFFERS; i++) {
		d = &ctx->descriptors[i];
		d->req_count      = cpu_to_le16(PAGE_SIZE);
		d->control        = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
						DESCRIPTOR_STATUS |
						DESCRIPTOR_BRANCH_ALWAYS);
		d->data_address   = cpu_to_le32(ar_buffer_bus(ctx, i));
		d->branch_address = cpu_to_le32(ctx->descriptors_bus +
			ar_next_buffer_index(i) * sizeof(struct descriptor));
	}

	return 0;

out_of_memory:
	ar_context_release(ctx);

	return -ENOMEM;
}

static void ar_context_run(struct ar_context *ctx)
{
	unsigned int i;

	for (i = 0; i < AR_BUFFERS; i++)
		ar_context_link_page(ctx, i);

	ctx->pointer = ctx->buffer;

	reg_write(ctx->ohci, COMMAND_PTR(ctx->regs), ctx->descriptors_bus | 1);
	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN);
}

static struct descriptor *find_branch_descriptor(struct descriptor *d, int z)
{
	__le16 branch;

	branch = d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS);

	/* figure out which descriptor the branch address goes in */
	if (z == 2 && branch == cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
		return d;
	else
		return d + z - 1;
}

static void context_tasklet(unsigned long data)
{
	struct context *ctx = (struct context *) data;
	struct descriptor *d, *last;
	u32 address;
	int z;
	struct descriptor_buffer *desc;

	desc = list_entry(ctx->buffer_list.next,
			struct descriptor_buffer, list);
	last = ctx->last;
	while (last->branch_address != 0) {
		struct descriptor_buffer *old_desc = desc;
		address = le32_to_cpu(last->branch_address);
		z = address & 0xf;
		address &= ~0xf;
		ctx->current_bus = address;

		/* If the branch address points to a buffer outside of the
		 * current buffer, advance to the next buffer. */
		if (address < desc->buffer_bus ||
				address >= desc->buffer_bus + desc->used)
			desc = list_entry(desc->list.next,
					struct descriptor_buffer, list);
		d = desc->buffer + (address - desc->buffer_bus) / sizeof(*d);
		last = find_branch_descriptor(d, z);

		if (!ctx->callback(ctx, d, last))
			break;

		if (old_desc != desc) {
			/* If we've advanced to the next buffer, move the
			 * previous buffer to the free list. */
			unsigned long flags;
			old_desc->used = 0;
			spin_lock_irqsave(&ctx->ohci->lock, flags);
			list_move_tail(&old_desc->list, &ctx->buffer_list);
			spin_unlock_irqrestore(&ctx->ohci->lock, flags);
		}
		ctx->last = last;
	}
}

/*
 * Allocate a new buffer and add it to the list of free buffers for this
 * context.  Must be called with ohci->lock held.
 */
static int context_add_buffer(struct context *ctx)
{
	struct descriptor_buffer *desc;
	dma_addr_t bus_addr;
	int offset;

	/*
	 * 16MB of descriptors should be far more than enough for any DMA
	 * program.  This will catch run-away userspace or DoS attacks.
	 */
	if (ctx->total_allocation >= 16*1024*1024)
		return -ENOMEM;

	desc = dmam_alloc_coherent(ctx->ohci->card.device, PAGE_SIZE, &bus_addr, GFP_ATOMIC);
	if (!desc)
		return -ENOMEM;

	offset = (void *)&desc->buffer - (void *)desc;
	/*
	 * Some controllers, like JMicron ones, always issue 0x20-byte DMA reads
	 * for descriptors, even 0x10-byte ones. This can cause page faults when
	 * an IOMMU is in use and the oversized read crosses a page boundary.
	 * Work around this by always leaving at least 0x10 bytes of padding.
	 */
	desc->buffer_size = PAGE_SIZE - offset - 0x10;
	desc->buffer_bus = bus_addr + offset;
	desc->used = 0;

	list_add_tail(&desc->list, &ctx->buffer_list);
	ctx->total_allocation += PAGE_SIZE;

	return 0;
}

static int context_init(struct context *ctx, struct fw_ohci *ohci,
			u32 regs, descriptor_callback_t callback)
{
	ctx->ohci = ohci;
	ctx->regs = regs;
	ctx->total_allocation = 0;

	INIT_LIST_HEAD(&ctx->buffer_list);
	if (context_add_buffer(ctx) < 0)
		return -ENOMEM;

	ctx->buffer_tail = list_entry(ctx->buffer_list.next,
			struct descriptor_buffer, list);

	tasklet_init(&ctx->tasklet, context_tasklet, (unsigned long)ctx);
	ctx->callback = callback;

	/*
	 * We put a dummy descriptor in the buffer that has a NULL
	 * branch address and looks like it's been sent.  That way we
	 * have a descriptor to append DMA programs to.
	 */
	memset(ctx->buffer_tail->buffer, 0, sizeof(*ctx->buffer_tail->buffer));
	ctx->buffer_tail->buffer->control = cpu_to_le16(DESCRIPTOR_OUTPUT_LAST);
	ctx->buffer_tail->buffer->transfer_status = cpu_to_le16(0x8011);
	ctx->buffer_tail->used += sizeof(*ctx->buffer_tail->buffer);
	ctx->last = ctx->buffer_tail->buffer;
	ctx->prev = ctx->buffer_tail->buffer;
	ctx->prev_z = 1;

	return 0;
}

static void context_release(struct context *ctx)
{
	struct fw_card *card = &ctx->ohci->card;
	struct descriptor_buffer *desc, *tmp;

	list_for_each_entry_safe(desc, tmp, &ctx->buffer_list, list) {
		dmam_free_coherent(card->device, PAGE_SIZE, desc,
				   desc->buffer_bus - ((void *)&desc->buffer - (void *)desc));
	}
}

/* Must be called with ohci->lock held */
static struct descriptor *context_get_descriptors(struct context *ctx,
						  int z, dma_addr_t *d_bus)
{
	struct descriptor *d = NULL;
	struct descriptor_buffer *desc = ctx->buffer_tail;

	if (z * sizeof(*d) > desc->buffer_size)
		return NULL;

	if (z * sizeof(*d) > desc->buffer_size - desc->used) {
		/* No room for the descriptor in this buffer, so advance to the
		 * next one. */

		if (desc->list.next == &ctx->buffer_list) {
			/* If there is no free buffer next in the list,
			 * allocate one. */
			if (context_add_buffer(ctx) < 0)
				return NULL;
		}
		desc = list_entry(desc->list.next,
				struct descriptor_buffer, list);
		ctx->buffer_tail = desc;
	}

	d = desc->buffer + desc->used / sizeof(*d);
	memset(d, 0, z * sizeof(*d));
	*d_bus = desc->buffer_bus + desc->used;

	return d;
}

static void context_run(struct context *ctx, u32 extra)
{
	struct fw_ohci *ohci = ctx->ohci;

	reg_write(ohci, COMMAND_PTR(ctx->regs),
		  le32_to_cpu(ctx->last->branch_address));
	reg_write(ohci, CONTROL_CLEAR(ctx->regs), ~0);
	reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_RUN | extra);
	ctx->running = true;
	flush_writes(ohci);
}

static void context_append(struct context *ctx,
			   struct descriptor *d, int z, int extra)
{
	dma_addr_t d_bus;
	struct descriptor_buffer *desc = ctx->buffer_tail;
	struct descriptor *d_branch;

	d_bus = desc->buffer_bus + (d - desc->buffer) * sizeof(*d);

	desc->used += (z + extra) * sizeof(*d);

	wmb(); /* finish init of new descriptors before branch_address update */

	d_branch = find_branch_descriptor(ctx->prev, ctx->prev_z);
	d_branch->branch_address = cpu_to_le32(d_bus | z);

	/*
	 * VT6306 incorrectly checks only the single descriptor at the
	 * CommandPtr when the wake bit is written, so if it's a
	 * multi-descriptor block starting with an INPUT_MORE, put a copy of
	 * the branch address in the first descriptor.
	 *
	 * Not doing this for transmit contexts since not sure how it interacts
	 * with skip addresses.
	 */
	if (unlikely(ctx->ohci->quirks & QUIRK_IR_WAKE) &&
	    d_branch != ctx->prev &&
	    (ctx->prev->control & cpu_to_le16(DESCRIPTOR_CMD)) ==
	     cpu_to_le16(DESCRIPTOR_INPUT_MORE)) {
		ctx->prev->branch_address = cpu_to_le32(d_bus | z);
	}

	ctx->prev = d;
	ctx->prev_z = z;
}

static void context_stop(struct context *ctx)
{
	struct fw_ohci *ohci = ctx->ohci;
	u32 reg;
	int i;

	reg_write(ohci, CONTROL_CLEAR(ctx->regs), CONTEXT_RUN);
	ctx->running = false;

	for (i = 0; i < 1000; i++) {
		reg = reg_read(ohci, CONTROL_SET(ctx->regs));
		if ((reg & CONTEXT_ACTIVE) == 0)
			return;

		if (i)
			udelay(10);
	}
	ohci_err(ohci, "DMA context still active (0x%08x)\n", reg);
}

struct driver_data {
	u8 inline_data[8];
	struct fw_packet *packet;
};

/*
 * This function apppends a packet to the DMA queue for transmission.
 * Must always be called with the ochi->lock held to ensure proper
 * generation handling and locking around packet queue manipulation.
 */
static int at_context_queue_packet(struct context *ctx,
				   struct fw_packet *packet)
{
	struct fw_ohci *ohci = ctx->ohci;
	dma_addr_t d_bus, payload_bus;
	struct driver_data *driver_data;
	struct descriptor *d, *last;
	__le32 *header;
	int z, tcode;

	d = context_get_descriptors(ctx, 4, &d_bus);
	if (d == NULL) {
		packet->ack = RCODE_SEND_ERROR;
		return -1;
	}

	d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
	d[0].res_count = cpu_to_le16(packet->timestamp);

	/*
	 * The DMA format for asynchronous link packets is different
	 * from the IEEE1394 layout, so shift the fields around
	 * accordingly.
	 */

	tcode = (packet->header[0] >> 4) & 0x0f;
	header = (__le32 *) &d[1];
	switch (tcode) {
	case TCODE_WRITE_QUADLET_REQUEST:
	case TCODE_WRITE_BLOCK_REQUEST:
	case TCODE_WRITE_RESPONSE:
	case TCODE_READ_QUADLET_REQUEST:
	case TCODE_READ_BLOCK_REQUEST:
	case TCODE_READ_QUADLET_RESPONSE:
	case TCODE_READ_BLOCK_RESPONSE:
	case TCODE_LOCK_REQUEST:
	case TCODE_LOCK_RESPONSE:
		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
					(packet->speed << 16));
		header[1] = cpu_to_le32((packet->header[1] & 0xffff) |
					(packet->header[0] & 0xffff0000));
		header[2] = cpu_to_le32(packet->header[2]);

		if (TCODE_IS_BLOCK_PACKET(tcode))
			header[3] = cpu_to_le32(packet->header[3]);
		else
			header[3] = (__force __le32) packet->header[3];

		d[0].req_count = cpu_to_le16(packet->header_length);
		break;

	case TCODE_LINK_INTERNAL:
		header[0] = cpu_to_le32((OHCI1394_phy_tcode << 4) |
					(packet->speed << 16));
		header[1] = cpu_to_le32(packet->header[1]);
		header[2] = cpu_to_le32(packet->header[2]);
		d[0].req_count = cpu_to_le16(12);

		if (is_ping_packet(&packet->header[1]))
			d[0].control |= cpu_to_le16(DESCRIPTOR_PING);
		break;

	case TCODE_STREAM_DATA:
		header[0] = cpu_to_le32((packet->header[0] & 0xffff) |
					(packet->speed << 16));
		header[1] = cpu_to_le32(packet->header[0] & 0xffff0000);
		d[0].req_count = cpu_to_le16(8);
		break;

	default:
		/* BUG(); */
		packet->ack = RCODE_SEND_ERROR;
		return -1;
	}

	BUILD_BUG_ON(sizeof(struct driver_data) > sizeof(struct descriptor));
	driver_data = (struct driver_data *) &d[3];
	driver_data->packet = packet;
	packet->driver_data = driver_data;

	if (packet->payload_length > 0) {
		if (packet->payload_length > sizeof(driver_data->inline_data)) {
			payload_bus = dma_map_single(ohci->card.device,
						     packet->payload,
						     packet->payload_length,
						     DMA_TO_DEVICE);
			if (dma_mapping_error(ohci->card.device, payload_bus)) {
				packet->ack = RCODE_SEND_ERROR;
				return -1;
			}
			packet->payload_bus	= payload_bus;
			packet->payload_mapped	= true;
		} else {
			memcpy(driver_data->inline_data, packet->payload,
			       packet->payload_length);
			payload_bus = d_bus + 3 * sizeof(*d);
		}

		d[2].req_count    = cpu_to_le16(packet->payload_length);
		d[2].data_address = cpu_to_le32(payload_bus);
		last = &d[2];
		z = 3;
	} else {
		last = &d[0];
		z = 2;
	}

	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
				     DESCRIPTOR_IRQ_ALWAYS |
				     DESCRIPTOR_BRANCH_ALWAYS);

	/* FIXME: Document how the locking works. */
	if (ohci->generation != packet->generation) {
		if (packet->payload_mapped)
			dma_unmap_single(ohci->card.device, payload_bus,
					 packet->payload_length, DMA_TO_DEVICE);
		packet->ack = RCODE_GENERATION;
		return -1;
	}

	context_append(ctx, d, z, 4 - z);

	if (ctx->running)
		reg_write(ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
	else
		context_run(ctx, 0);

	return 0;
}

static void at_context_flush(struct context *ctx)
{
	tasklet_disable(&ctx->tasklet);

	ctx->flushing = true;
	context_tasklet((unsigned long)ctx);
	ctx->flushing = false;

	tasklet_enable(&ctx->tasklet);
}

static int handle_at_packet(struct context *context,
			    struct descriptor *d,
			    struct descriptor *last)
{
	struct driver_data *driver_data;
	struct fw_packet *packet;
	struct fw_ohci *ohci = context->ohci;
	int evt;

	if (last->transfer_status == 0 && !context->flushing)
		/* This descriptor isn't done yet, stop iteration. */
		return 0;

	driver_data = (struct driver_data *) &d[3];
	packet = driver_data->packet;
	if (packet == NULL)
		/* This packet was cancelled, just continue. */
		return 1;

	if (packet->payload_mapped)
		dma_unmap_single(ohci->card.device, packet->payload_bus,
				 packet->payload_length, DMA_TO_DEVICE);

	evt = le16_to_cpu(last->transfer_status) & 0x1f;
	packet->timestamp = le16_to_cpu(last->res_count);

	log_ar_at_event(ohci, 'T', packet->speed, packet->header, evt);

	switch (evt) {
	case OHCI1394_evt_timeout:
		/* Async response transmit timed out. */
		packet->ack = RCODE_CANCELLED;
		break;

	case OHCI1394_evt_flushed:
		/*
		 * The packet was flushed should give same error as
		 * when we try to use a stale generation count.
		 */
		packet->ack = RCODE_GENERATION;
		break;

	case OHCI1394_evt_missing_ack:
		if (context->flushing)
			packet->ack = RCODE_GENERATION;
		else {
			/*
			 * Using a valid (current) generation count, but the
			 * node is not on the bus or not sending acks.
			 */
			packet->ack = RCODE_NO_ACK;
		}
		break;

	case ACK_COMPLETE + 0x10:
	case ACK_PENDING + 0x10:
	case ACK_BUSY_X + 0x10:
	case ACK_BUSY_A + 0x10:
	case ACK_BUSY_B + 0x10:
	case ACK_DATA_ERROR + 0x10:
	case ACK_TYPE_ERROR + 0x10:
		packet->ack = evt - 0x10;
		break;

	case OHCI1394_evt_no_status:
		if (context->flushing) {
			packet->ack = RCODE_GENERATION;
			break;
		}
		fallthrough;

	default:
		packet->ack = RCODE_SEND_ERROR;
		break;
	}

	packet->callback(packet, &ohci->card, packet->ack);

	return 1;
}

#define HEADER_GET_DESTINATION(q)	(((q) >> 16) & 0xffff)
#define HEADER_GET_TCODE(q)		(((q) >> 4) & 0x0f)
#define HEADER_GET_OFFSET_HIGH(q)	(((q) >> 0) & 0xffff)
#define HEADER_GET_DATA_LENGTH(q)	(((q) >> 16) & 0xffff)
#define HEADER_GET_EXTENDED_TCODE(q)	(((q) >> 0) & 0xffff)

static u32 get_cycle_time(struct fw_ohci *ohci);

static void handle_local_rom(struct fw_ohci *ohci,
			     struct fw_packet *packet, u32 csr)
{
	struct fw_packet response;
	int tcode, length, i;

	tcode = HEADER_GET_TCODE(packet->header[0]);
	if (TCODE_IS_BLOCK_PACKET(tcode))
		length = HEADER_GET_DATA_LENGTH(packet->header[3]);
	else
		length = 4;

	i = csr - CSR_CONFIG_ROM;
	if (i + length > CONFIG_ROM_SIZE) {
		fw_fill_response(&response, packet->header,
				 RCODE_ADDRESS_ERROR, NULL, 0);
	} else if (!TCODE_IS_READ_REQUEST(tcode)) {
		fw_fill_response(&response, packet->header,
				 RCODE_TYPE_ERROR, NULL, 0);
	} else {
		fw_fill_response(&response, packet->header, RCODE_COMPLETE,
				 (void *) ohci->config_rom + i, length);
	}

	// Timestamping on behalf of the hardware.
	response.timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ohci));
	fw_core_handle_response(&ohci->card, &response);
}

static void handle_local_lock(struct fw_ohci *ohci,
			      struct fw_packet *packet, u32 csr)
{
	struct fw_packet response;
	int tcode, length, ext_tcode, sel, try;
	__be32 *payload, lock_old;
	u32 lock_arg, lock_data;

	tcode = HEADER_GET_TCODE(packet->header[0]);
	length = HEADER_GET_DATA_LENGTH(packet->header[3]);
	payload = packet->payload;
	ext_tcode = HEADER_GET_EXTENDED_TCODE(packet->header[3]);

	if (tcode == TCODE_LOCK_REQUEST &&
	    ext_tcode == EXTCODE_COMPARE_SWAP && length == 8) {
		lock_arg = be32_to_cpu(payload[0]);
		lock_data = be32_to_cpu(payload[1]);
	} else if (tcode == TCODE_READ_QUADLET_REQUEST) {
		lock_arg = 0;
		lock_data = 0;
	} else {
		fw_fill_response(&response, packet->header,
				 RCODE_TYPE_ERROR, NULL, 0);
		goto out;
	}

	sel = (csr - CSR_BUS_MANAGER_ID) / 4;
	reg_write(ohci, OHCI1394_CSRData, lock_data);
	reg_write(ohci, OHCI1394_CSRCompareData, lock_arg);
	reg_write(ohci, OHCI1394_CSRControl, sel);

	for (try = 0; try < 20; try++)
		if (reg_read(ohci, OHCI1394_CSRControl) & 0x80000000) {
			lock_old = cpu_to_be32(reg_read(ohci,
							OHCI1394_CSRData));
			fw_fill_response(&response, packet->header,
					 RCODE_COMPLETE,
					 &lock_old, sizeof(lock_old));
			goto out;
		}

	ohci_err(ohci, "swap not done (CSR lock timeout)\n");
	fw_fill_response(&response, packet->header, RCODE_BUSY, NULL, 0);

 out:
	// Timestamping on behalf of the hardware.
	response.timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ohci));
	fw_core_handle_response(&ohci->card, &response);
}

static void handle_local_request(struct context *ctx, struct fw_packet *packet)
{
	u64 offset, csr;

	if (ctx == &ctx->ohci->at_request_ctx) {
		packet->ack = ACK_PENDING;
		packet->callback(packet, &ctx->ohci->card, packet->ack);
	}

	offset =
		((unsigned long long)
		 HEADER_GET_OFFSET_HIGH(packet->header[1]) << 32) |
		packet->header[2];
	csr = offset - CSR_REGISTER_BASE;

	/* Handle config rom reads. */
	if (csr >= CSR_CONFIG_ROM && csr < CSR_CONFIG_ROM_END)
		handle_local_rom(ctx->ohci, packet, csr);
	else switch (csr) {
	case CSR_BUS_MANAGER_ID:
	case CSR_BANDWIDTH_AVAILABLE:
	case CSR_CHANNELS_AVAILABLE_HI:
	case CSR_CHANNELS_AVAILABLE_LO:
		handle_local_lock(ctx->ohci, packet, csr);
		break;
	default:
		if (ctx == &ctx->ohci->at_request_ctx)
			fw_core_handle_request(&ctx->ohci->card, packet);
		else
			fw_core_handle_response(&ctx->ohci->card, packet);
		break;
	}

	if (ctx == &ctx->ohci->at_response_ctx) {
		packet->ack = ACK_COMPLETE;
		packet->callback(packet, &ctx->ohci->card, packet->ack);
	}
}

static void at_context_transmit(struct context *ctx, struct fw_packet *packet)
{
	unsigned long flags;
	int ret;

	spin_lock_irqsave(&ctx->ohci->lock, flags);

	if (HEADER_GET_DESTINATION(packet->header[0]) == ctx->ohci->node_id &&
	    ctx->ohci->generation == packet->generation) {
		spin_unlock_irqrestore(&ctx->ohci->lock, flags);

		// Timestamping on behalf of the hardware.
		packet->timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ctx->ohci));

		handle_local_request(ctx, packet);
		return;
	}

	ret = at_context_queue_packet(ctx, packet);
	spin_unlock_irqrestore(&ctx->ohci->lock, flags);

	if (ret < 0) {
		// Timestamping on behalf of the hardware.
		packet->timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ctx->ohci));

		packet->callback(packet, &ctx->ohci->card, packet->ack);
	}
}

static void detect_dead_context(struct fw_ohci *ohci,
				const char *name, unsigned int regs)
{
	u32 ctl;

	ctl = reg_read(ohci, CONTROL_SET(regs));
	if (ctl & CONTEXT_DEAD)
		ohci_err(ohci, "DMA context %s has stopped, error code: %s\n",
			name, evts[ctl & 0x1f]);
}

static void handle_dead_contexts(struct fw_ohci *ohci)
{
	unsigned int i;
	char name[8];

	detect_dead_context(ohci, "ATReq", OHCI1394_AsReqTrContextBase);
	detect_dead_context(ohci, "ATRsp", OHCI1394_AsRspTrContextBase);
	detect_dead_context(ohci, "ARReq", OHCI1394_AsReqRcvContextBase);
	detect_dead_context(ohci, "ARRsp", OHCI1394_AsRspRcvContextBase);
	for (i = 0; i < 32; ++i) {
		if (!(ohci->it_context_support & (1 << i)))
			continue;
		sprintf(name, "IT%u", i);
		detect_dead_context(ohci, name, OHCI1394_IsoXmitContextBase(i));
	}
	for (i = 0; i < 32; ++i) {
		if (!(ohci->ir_context_support & (1 << i)))
			continue;
		sprintf(name, "IR%u", i);
		detect_dead_context(ohci, name, OHCI1394_IsoRcvContextBase(i));
	}
	/* TODO: maybe try to flush and restart the dead contexts */
}

static u32 cycle_timer_ticks(u32 cycle_timer)
{
	u32 ticks;

	ticks = cycle_timer & 0xfff;
	ticks += 3072 * ((cycle_timer >> 12) & 0x1fff);
	ticks += (3072 * 8000) * (cycle_timer >> 25);

	return ticks;
}

/*
 * Some controllers exhibit one or more of the following bugs when updating the
 * iso cycle timer register:
 *  - When the lowest six bits are wrapping around to zero, a read that happens
 *    at the same time will return garbage in the lowest ten bits.
 *  - When the cycleOffset field wraps around to zero, the cycleCount field is
 *    not incremented for about 60 ns.
 *  - Occasionally, the entire register reads zero.
 *
 * To catch these, we read the register three times and ensure that the
 * difference between each two consecutive reads is approximately the same, i.e.
 * less than twice the other.  Furthermore, any negative difference indicates an
 * error.  (A PCI read should take at least 20 ticks of the 24.576 MHz timer to
 * execute, so we have enough precision to compute the ratio of the differences.)
 */
static u32 get_cycle_time(struct fw_ohci *ohci)
{
	u32 c0, c1, c2;
	u32 t0, t1, t2;
	s32 diff01, diff12;
	int i;

	if (has_reboot_by_cycle_timer_read_quirk(ohci))
		return 0;

	c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);

	if (ohci->quirks & QUIRK_CYCLE_TIMER) {
		i = 0;
		c1 = c2;
		c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
		do {
			c0 = c1;
			c1 = c2;
			c2 = reg_read(ohci, OHCI1394_IsochronousCycleTimer);
			t0 = cycle_timer_ticks(c0);
			t1 = cycle_timer_ticks(c1);
			t2 = cycle_timer_ticks(c2);
			diff01 = t1 - t0;
			diff12 = t2 - t1;
		} while ((diff01 <= 0 || diff12 <= 0 ||
			  diff01 / diff12 >= 2 || diff12 / diff01 >= 2)
			 && i++ < 20);
	}

	return c2;
}

/*
 * This function has to be called at least every 64 seconds.  The bus_time
 * field stores not only the upper 25 bits of the BUS_TIME register but also
 * the most significant bit of the cycle timer in bit 6 so that we can detect
 * changes in this bit.
 */
static u32 update_bus_time(struct fw_ohci *ohci)
{
	u32 cycle_time_seconds = get_cycle_time(ohci) >> 25;

	if (unlikely(!ohci->bus_time_running)) {
		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_cycle64Seconds);
		ohci->bus_time = (lower_32_bits(ktime_get_seconds()) & ~0x7f) |
		                 (cycle_time_seconds & 0x40);
		ohci->bus_time_running = true;
	}

	if ((ohci->bus_time & 0x40) != (cycle_time_seconds & 0x40))
		ohci->bus_time += 0x40;

	return ohci->bus_time | cycle_time_seconds;
}

static int get_status_for_port(struct fw_ohci *ohci, int port_index)
{
	int reg;

	mutex_lock(&ohci->phy_reg_mutex);
	reg = write_phy_reg(ohci, 7, port_index);
	if (reg >= 0)
		reg = read_phy_reg(ohci, 8);
	mutex_unlock(&ohci->phy_reg_mutex);
	if (reg < 0)
		return reg;

	switch (reg & 0x0f) {
	case 0x06:
		return 2;	/* is child node (connected to parent node) */
	case 0x0e:
		return 3;	/* is parent node (connected to child node) */
	}
	return 1;		/* not connected */
}

static int get_self_id_pos(struct fw_ohci *ohci, u32 self_id,
	int self_id_count)
{
	int i;
	u32 entry;

	for (i = 0; i < self_id_count; i++) {
		entry = ohci->self_id_buffer[i];
		if ((self_id & 0xff000000) == (entry & 0xff000000))
			return -1;
		if ((self_id & 0xff000000) < (entry & 0xff000000))
			return i;
	}
	return i;
}

static int initiated_reset(struct fw_ohci *ohci)
{
	int reg;
	int ret = 0;

	mutex_lock(&ohci->phy_reg_mutex);
	reg = write_phy_reg(ohci, 7, 0xe0); /* Select page 7 */
	if (reg >= 0) {
		reg = read_phy_reg(ohci, 8);
		reg |= 0x40;
		reg = write_phy_reg(ohci, 8, reg); /* set PMODE bit */
		if (reg >= 0) {
			reg = read_phy_reg(ohci, 12); /* read register 12 */
			if (reg >= 0) {
				if ((reg & 0x08) == 0x08) {
					/* bit 3 indicates "initiated reset" */
					ret = 0x2;
				}
			}
		}
	}
	mutex_unlock(&ohci->phy_reg_mutex);
	return ret;
}

/*
 * TI TSB82AA2B and TSB12LV26 do not receive the selfID of a locally
 * attached TSB41BA3D phy; see http://www.ti.com/litv/pdf/sllz059.
 * Construct the selfID from phy register contents.
 */
static int find_and_insert_self_id(struct fw_ohci *ohci, int self_id_count)
{
	int reg, i, pos, status;
	/* link active 1, speed 3, bridge 0, contender 1, more packets 0 */
	u32 self_id = 0x8040c800;

	reg = reg_read(ohci, OHCI1394_NodeID);
	if (!(reg & OHCI1394_NodeID_idValid)) {
		ohci_notice(ohci,
			    "node ID not valid, new bus reset in progress\n");
		return -EBUSY;
	}
	self_id |= ((reg & 0x3f) << 24); /* phy ID */

	reg = ohci_read_phy_reg(&ohci->card, 4);
	if (reg < 0)
		return reg;
	self_id |= ((reg & 0x07) << 8); /* power class */

	reg = ohci_read_phy_reg(&ohci->card, 1);
	if (reg < 0)
		return reg;
	self_id |= ((reg & 0x3f) << 16); /* gap count */

	for (i = 0; i < 3; i++) {
		status = get_status_for_port(ohci, i);
		if (status < 0)
			return status;
		self_id |= ((status & 0x3) << (6 - (i * 2)));
	}

	self_id |= initiated_reset(ohci);

	pos = get_self_id_pos(ohci, self_id, self_id_count);
	if (pos >= 0) {
		memmove(&(ohci->self_id_buffer[pos+1]),
			&(ohci->self_id_buffer[pos]),
			(self_id_count - pos) * sizeof(*ohci->self_id_buffer));
		ohci->self_id_buffer[pos] = self_id;
		self_id_count++;
	}
	return self_id_count;
}

static void bus_reset_work(struct work_struct *work)
{
	struct fw_ohci *ohci =
		container_of(work, struct fw_ohci, bus_reset_work);
	int self_id_count, generation, new_generation, i, j;
	u32 reg;
	void *free_rom = NULL;
	dma_addr_t free_rom_bus = 0;
	bool is_new_root;

	reg = reg_read(ohci, OHCI1394_NodeID);
	if (!(reg & OHCI1394_NodeID_idValid)) {
		ohci_notice(ohci,
			    "node ID not valid, new bus reset in progress\n");
		return;
	}
	if ((reg & OHCI1394_NodeID_nodeNumber) == 63) {
		ohci_notice(ohci, "malconfigured bus\n");
		return;
	}
	ohci->node_id = reg & (OHCI1394_NodeID_busNumber |
			       OHCI1394_NodeID_nodeNumber);

	is_new_root = (reg & OHCI1394_NodeID_root) != 0;
	if (!(ohci->is_root && is_new_root))
		reg_write(ohci, OHCI1394_LinkControlSet,
			  OHCI1394_LinkControl_cycleMaster);
	ohci->is_root = is_new_root;

	reg = reg_read(ohci, OHCI1394_SelfIDCount);
	if (reg & OHCI1394_SelfIDCount_selfIDError) {
		ohci_notice(ohci, "self ID receive error\n");
		return;
	}
	/*
	 * The count in the SelfIDCount register is the number of
	 * bytes in the self ID receive buffer.  Since we also receive
	 * the inverted quadlets and a header quadlet, we shift one
	 * bit extra to get the actual number of self IDs.
	 */
	self_id_count = (reg >> 3) & 0xff;

	if (self_id_count > 252) {
		ohci_notice(ohci, "bad selfIDSize (%08x)\n", reg);
		return;
	}

	generation = (cond_le32_to_cpu(ohci->self_id[0]) >> 16) & 0xff;
	rmb();

	for (i = 1, j = 0; j < self_id_count; i += 2, j++) {
		u32 id  = cond_le32_to_cpu(ohci->self_id[i]);
		u32 id2 = cond_le32_to_cpu(ohci->self_id[i + 1]);

		if (id != ~id2) {
			/*
			 * If the invalid data looks like a cycle start packet,
			 * it's likely to be the result of the cycle master
			 * having a wrong gap count.  In this case, the self IDs
			 * so far are valid and should be processed so that the
			 * bus manager can then correct the gap count.
			 */
			if (id == 0xffff008f) {
				ohci_notice(ohci, "ignoring spurious self IDs\n");
				self_id_count = j;
				break;
			}

			ohci_notice(ohci, "bad self ID %d/%d (%08x != ~%08x)\n",
				    j, self_id_count, id, id2);
			return;
		}
		ohci->self_id_buffer[j] = id;
	}

	if (ohci->quirks & QUIRK_TI_SLLZ059) {
		self_id_count = find_and_insert_self_id(ohci, self_id_count);
		if (self_id_count < 0) {
			ohci_notice(ohci,
				    "could not construct local self ID\n");
			return;
		}
	}

	if (self_id_count == 0) {
		ohci_notice(ohci, "no self IDs\n");
		return;
	}
	rmb();

	/*
	 * Check the consistency of the self IDs we just read.  The
	 * problem we face is that a new bus reset can start while we
	 * read out the self IDs from the DMA buffer. If this happens,
	 * the DMA buffer will be overwritten with new self IDs and we
	 * will read out inconsistent data.  The OHCI specification
	 * (section 11.2) recommends a technique similar to
	 * linux/seqlock.h, where we remember the generation of the
	 * self IDs in the buffer before reading them out and compare
	 * it to the current generation after reading them out.  If
	 * the two generations match we know we have a consistent set
	 * of self IDs.
	 */

	new_generation = (reg_read(ohci, OHCI1394_SelfIDCount) >> 16) & 0xff;
	if (new_generation != generation) {
		ohci_notice(ohci, "new bus reset, discarding self ids\n");
		return;
	}

	/* FIXME: Document how the locking works. */
	spin_lock_irq(&ohci->lock);

	ohci->generation = -1; /* prevent AT packet queueing */
	context_stop(&ohci->at_request_ctx);
	context_stop(&ohci->at_response_ctx);

	spin_unlock_irq(&ohci->lock);

	/*
	 * Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
	 * packets in the AT queues and software needs to drain them.
	 * Some OHCI 1.1 controllers (JMicron) apparently require this too.
	 */
	at_context_flush(&ohci->at_request_ctx);
	at_context_flush(&ohci->at_response_ctx);

	spin_lock_irq(&ohci->lock);

	ohci->generation = generation;
	reg_write(ohci, OHCI1394_IntEventClear, OHCI1394_busReset);
	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
		reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_busReset);

	if (ohci->quirks & QUIRK_RESET_PACKET)
		ohci->request_generation = generation;

	/*
	 * This next bit is unrelated to the AT context stuff but we
	 * have to do it under the spinlock also.  If a new config rom
	 * was set up before this reset, the old one is now no longer
	 * in use and we can free it. Update the config rom pointers
	 * to point to the current config rom and clear the
	 * next_config_rom pointer so a new update can take place.
	 */

	if (ohci->next_config_rom != NULL) {
		if (ohci->next_config_rom != ohci->config_rom) {
			free_rom      = ohci->config_rom;
			free_rom_bus  = ohci->config_rom_bus;
		}
		ohci->config_rom      = ohci->next_config_rom;
		ohci->config_rom_bus  = ohci->next_config_rom_bus;
		ohci->next_config_rom = NULL;

		/*
		 * Restore config_rom image and manually update
		 * config_rom registers.  Writing the header quadlet
		 * will indicate that the config rom is ready, so we
		 * do that last.
		 */
		reg_write(ohci, OHCI1394_BusOptions,
			  be32_to_cpu(ohci->config_rom[2]));
		ohci->config_rom[0] = ohci->next_header;
		reg_write(ohci, OHCI1394_ConfigROMhdr,
			  be32_to_cpu(ohci->next_header));
	}

	if (param_remote_dma) {
		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, ~0);
		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, ~0);
	}

	spin_unlock_irq(&ohci->lock);

	if (free_rom)
		dmam_free_coherent(ohci->card.device, CONFIG_ROM_SIZE, free_rom, free_rom_bus);

	log_selfids(ohci, generation, self_id_count);

	fw_core_handle_bus_reset(&ohci->card, ohci->node_id, generation,
				 self_id_count, ohci->self_id_buffer,
				 ohci->csr_state_setclear_abdicate);
	ohci->csr_state_setclear_abdicate = false;
}

static irqreturn_t irq_handler(int irq, void *data)
{
	struct fw_ohci *ohci = data;
	u32 event, iso_event;
	int i;

	event = reg_read(ohci, OHCI1394_IntEventClear);

	if (!event || !~event)
		return IRQ_NONE;

	/*
	 * busReset and postedWriteErr events must not be cleared yet
	 * (OHCI 1.1 clauses 7.2.3.2 and 13.2.8.1)
	 */
	reg_write(ohci, OHCI1394_IntEventClear,
		  event & ~(OHCI1394_busReset | OHCI1394_postedWriteErr));
	log_irqs(ohci, event);
	if (event & OHCI1394_busReset)
		reg_write(ohci, OHCI1394_IntMaskClear, OHCI1394_busReset);

	if (event & OHCI1394_selfIDComplete)
		queue_work(selfid_workqueue, &ohci->bus_reset_work);

	if (event & OHCI1394_RQPkt)
		tasklet_schedule(&ohci->ar_request_ctx.tasklet);

	if (event & OHCI1394_RSPkt)
		tasklet_schedule(&ohci->ar_response_ctx.tasklet);

	if (event & OHCI1394_reqTxComplete)
		tasklet_schedule(&ohci->at_request_ctx.tasklet);

	if (event & OHCI1394_respTxComplete)
		tasklet_schedule(&ohci->at_response_ctx.tasklet);

	if (event & OHCI1394_isochRx) {
		iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventClear);
		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);

		while (iso_event) {
			i = ffs(iso_event) - 1;
			tasklet_schedule(
				&ohci->ir_context_list[i].context.tasklet);
			iso_event &= ~(1 << i);
		}
	}

	if (event & OHCI1394_isochTx) {
		iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventClear);
		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);

		while (iso_event) {
			i = ffs(iso_event) - 1;
			tasklet_schedule(
				&ohci->it_context_list[i].context.tasklet);
			iso_event &= ~(1 << i);
		}
	}

	if (unlikely(event & OHCI1394_regAccessFail))
		ohci_err(ohci, "register access failure\n");

	if (unlikely(event & OHCI1394_postedWriteErr)) {
		reg_read(ohci, OHCI1394_PostedWriteAddressHi);
		reg_read(ohci, OHCI1394_PostedWriteAddressLo);
		reg_write(ohci, OHCI1394_IntEventClear,
			  OHCI1394_postedWriteErr);
		if (printk_ratelimit())
			ohci_err(ohci, "PCI posted write error\n");
	}

	if (unlikely(event & OHCI1394_cycleTooLong)) {
		if (printk_ratelimit())
			ohci_notice(ohci, "isochronous cycle too long\n");
		reg_write(ohci, OHCI1394_LinkControlSet,
			  OHCI1394_LinkControl_cycleMaster);
	}

	if (unlikely(event & OHCI1394_cycleInconsistent)) {
		/*
		 * We need to clear this event bit in order to make
		 * cycleMatch isochronous I/O work.  In theory we should
		 * stop active cycleMatch iso contexts now and restart
		 * them at least two cycles later.  (FIXME?)
		 */
		if (printk_ratelimit())
			ohci_notice(ohci, "isochronous cycle inconsistent\n");
	}

	if (unlikely(event & OHCI1394_unrecoverableError))
		handle_dead_contexts(ohci);

	if (event & OHCI1394_cycle64Seconds) {
		spin_lock(&ohci->lock);
		update_bus_time(ohci);
		spin_unlock(&ohci->lock);
	} else
		flush_writes(ohci);

	return IRQ_HANDLED;
}

static int software_reset(struct fw_ohci *ohci)
{
	u32 val;
	int i;

	reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
	for (i = 0; i < 500; i++) {
		val = reg_read(ohci, OHCI1394_HCControlSet);
		if (!~val)
			return -ENODEV; /* Card was ejected. */

		if (!(val & OHCI1394_HCControl_softReset))
			return 0;

		msleep(1);
	}

	return -EBUSY;
}

static void copy_config_rom(__be32 *dest, const __be32 *src, size_t length)
{
	size_t size = length * 4;

	memcpy(dest, src, size);
	if (size < CONFIG_ROM_SIZE)
		memset(&dest[length], 0, CONFIG_ROM_SIZE - size);
}

static int configure_1394a_enhancements(struct fw_ohci *ohci)
{
	bool enable_1394a;
	int ret, clear, set, offset;

	/* Check if the driver should configure link and PHY. */
	if (!(reg_read(ohci, OHCI1394_HCControlSet) &
	      OHCI1394_HCControl_programPhyEnable))
		return 0;

	/* Paranoia: check whether the PHY supports 1394a, too. */
	enable_1394a = false;
	ret = read_phy_reg(ohci, 2);
	if (ret < 0)
		return ret;
	if ((ret & PHY_EXTENDED_REGISTERS) == PHY_EXTENDED_REGISTERS) {
		ret = read_paged_phy_reg(ohci, 1, 8);
		if (ret < 0)
			return ret;
		if (ret >= 1)
			enable_1394a = true;
	}

	if (ohci->quirks & QUIRK_NO_1394A)
		enable_1394a = false;

	/* Configure PHY and link consistently. */
	if (enable_1394a) {
		clear = 0;
		set = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
	} else {
		clear = PHY_ENABLE_ACCEL | PHY_ENABLE_MULTI;
		set = 0;
	}
	ret = update_phy_reg(ohci, 5, clear, set);
	if (ret < 0)
		return ret;

	if (enable_1394a)
		offset = OHCI1394_HCControlSet;
	else
		offset = OHCI1394_HCControlClear;
	reg_write(ohci, offset, OHCI1394_HCControl_aPhyEnhanceEnable);

	/* Clean up: configuration has been taken care of. */
	reg_write(ohci, OHCI1394_HCControlClear,
		  OHCI1394_HCControl_programPhyEnable);

	return 0;
}

static int probe_tsb41ba3d(struct fw_ohci *ohci)
{
	/* TI vendor ID = 0x080028, TSB41BA3D product ID = 0x833005 (sic) */
	static const u8 id[] = { 0x08, 0x00, 0x28, 0x83, 0x30, 0x05, };
	int reg, i;

	reg = read_phy_reg(ohci, 2);
	if (reg < 0)
		return reg;
	if ((reg & PHY_EXTENDED_REGISTERS) != PHY_EXTENDED_REGISTERS)
		return 0;

	for (i = ARRAY_SIZE(id) - 1; i >= 0; i--) {
		reg = read_paged_phy_reg(ohci, 1, i + 10);
		if (reg < 0)
			return reg;
		if (reg != id[i])
			return 0;
	}
	return 1;
}

static int ohci_enable(struct fw_card *card,
		       const __be32 *config_rom, size_t length)
{
	struct fw_ohci *ohci = fw_ohci(card);
	u32 lps, version, irqs;
	int i, ret;

	ret = software_reset(ohci);
	if (ret < 0) {
		ohci_err(ohci, "failed to reset ohci card\n");
		return ret;
	}

	/*
	 * Now enable LPS, which we need in order to start accessing
	 * most of the registers.  In fact, on some cards (ALI M5251),
	 * accessing registers in the SClk domain without LPS enabled
	 * will lock up the machine.  Wait 50msec to make sure we have
	 * full link enabled.  However, with some cards (well, at least
	 * a JMicron PCIe card), we have to try again sometimes.
	 *
	 * TI TSB82AA2 + TSB81BA3(A) cards signal LPS enabled early but
	 * cannot actually use the phy at that time.  These need tens of
	 * millisecods pause between LPS write and first phy access too.
	 */

	reg_write(ohci, OHCI1394_HCControlSet,
		  OHCI1394_HCControl_LPS |
		  OHCI1394_HCControl_postedWriteEnable);
	flush_writes(ohci);

	for (lps = 0, i = 0; !lps && i < 3; i++) {
		msleep(50);
		lps = reg_read(ohci, OHCI1394_HCControlSet) &
		      OHCI1394_HCControl_LPS;
	}

	if (!lps) {
		ohci_err(ohci, "failed to set Link Power Status\n");
		return -EIO;
	}

	if (ohci->quirks & QUIRK_TI_SLLZ059) {
		ret = probe_tsb41ba3d(ohci);
		if (ret < 0)
			return ret;
		if (ret)
			ohci_notice(ohci, "local TSB41BA3D phy\n");
		else
			ohci->quirks &= ~QUIRK_TI_SLLZ059;
	}

	reg_write(ohci, OHCI1394_HCControlClear,
		  OHCI1394_HCControl_noByteSwapData);

	reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
	reg_write(ohci, OHCI1394_LinkControlSet,
		  OHCI1394_LinkControl_cycleTimerEnable |
		  OHCI1394_LinkControl_cycleMaster);

	reg_write(ohci, OHCI1394_ATRetries,
		  OHCI1394_MAX_AT_REQ_RETRIES |
		  (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
		  (OHCI1394_MAX_PHYS_RESP_RETRIES << 8) |
		  (200 << 16));

	ohci->bus_time_running = false;

	for (i = 0; i < 32; i++)
		if (ohci->ir_context_support & (1 << i))
			reg_write(ohci, OHCI1394_IsoRcvContextControlClear(i),
				  IR_CONTEXT_MULTI_CHANNEL_MODE);

	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
	if (version >= OHCI_VERSION_1_1) {
		reg_write(ohci, OHCI1394_InitialChannelsAvailableHi,
			  0xfffffffe);
		card->broadcast_channel_auto_allocated = true;
	}

	/* Get implemented bits of the priority arbitration request counter. */
	reg_write(ohci, OHCI1394_FairnessControl, 0x3f);
	ohci->pri_req_max = reg_read(ohci, OHCI1394_FairnessControl) & 0x3f;
	reg_write(ohci, OHCI1394_FairnessControl, 0);
	card->priority_budget_implemented = ohci->pri_req_max != 0;

	reg_write(ohci, OHCI1394_PhyUpperBound, FW_MAX_PHYSICAL_RANGE >> 16);
	reg_write(ohci, OHCI1394_IntEventClear, ~0);
	reg_write(ohci, OHCI1394_IntMaskClear, ~0);

	ret = configure_1394a_enhancements(ohci);
	if (ret < 0)
		return ret;

	/* Activate link_on bit and contender bit in our self ID packets.*/
	ret = ohci_update_phy_reg(card, 4, 0, PHY_LINK_ACTIVE | PHY_CONTENDER);
	if (ret < 0)
		return ret;

	/*
	 * When the link is not yet enabled, the atomic config rom
	 * update mechanism described below in ohci_set_config_rom()
	 * is not active.  We have to update ConfigRomHeader and
	 * BusOptions manually, and the write to ConfigROMmap takes
	 * effect immediately.  We tie this to the enabling of the
	 * link, so we have a valid config rom before enabling - the
	 * OHCI requires that ConfigROMhdr and BusOptions have valid
	 * values before enabling.
	 *
	 * However, when the ConfigROMmap is written, some controllers
	 * always read back quadlets 0 and 2 from the config rom to
	 * the ConfigRomHeader and BusOptions registers on bus reset.
	 * They shouldn't do that in this initial case where the link
	 * isn't enabled.  This means we have to use the same
	 * workaround here, setting the bus header to 0 and then write
	 * the right values in the bus reset tasklet.
	 */

	if (config_rom) {
		ohci->next_config_rom = dmam_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
							    &ohci->next_config_rom_bus, GFP_KERNEL);
		if (ohci->next_config_rom == NULL)
			return -ENOMEM;

		copy_config_rom(ohci->next_config_rom, config_rom, length);
	} else {
		/*
		 * In the suspend case, config_rom is NULL, which
		 * means that we just reuse the old config rom.
		 */
		ohci->next_config_rom = ohci->config_rom;
		ohci->next_config_rom_bus = ohci->config_rom_bus;
	}

	ohci->next_header = ohci->next_config_rom[0];
	ohci->next_config_rom[0] = 0;
	reg_write(ohci, OHCI1394_ConfigROMhdr, 0);
	reg_write(ohci, OHCI1394_BusOptions,
		  be32_to_cpu(ohci->next_config_rom[2]));
	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);

	reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);

	irqs =	OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
		OHCI1394_RQPkt | OHCI1394_RSPkt |
		OHCI1394_isochTx | OHCI1394_isochRx |
		OHCI1394_postedWriteErr |
		OHCI1394_selfIDComplete |
		OHCI1394_regAccessFail |
		OHCI1394_cycleInconsistent |
		OHCI1394_unrecoverableError |
		OHCI1394_cycleTooLong |
		OHCI1394_masterIntEnable;
	if (param_debug & OHCI_PARAM_DEBUG_BUSRESETS)
		irqs |= OHCI1394_busReset;
	reg_write(ohci, OHCI1394_IntMaskSet, irqs);

	reg_write(ohci, OHCI1394_HCControlSet,
		  OHCI1394_HCControl_linkEnable |
		  OHCI1394_HCControl_BIBimageValid);

	reg_write(ohci, OHCI1394_LinkControlSet,
		  OHCI1394_LinkControl_rcvSelfID |
		  OHCI1394_LinkControl_rcvPhyPkt);

	ar_context_run(&ohci->ar_request_ctx);
	ar_context_run(&ohci->ar_response_ctx);

	flush_writes(ohci);

	/* We are ready to go, reset bus to finish initialization. */
	fw_schedule_bus_reset(&ohci->card, false, true);

	return 0;
}

static int ohci_set_config_rom(struct fw_card *card,
			       const __be32 *config_rom, size_t length)
{
	struct fw_ohci *ohci;
	__be32 *next_config_rom;
	dma_addr_t next_config_rom_bus;

	ohci = fw_ohci(card);

	/*
	 * When the OHCI controller is enabled, the config rom update
	 * mechanism is a bit tricky, but easy enough to use.  See
	 * section 5.5.6 in the OHCI specification.
	 *
	 * The OHCI controller caches the new config rom address in a
	 * shadow register (ConfigROMmapNext) and needs a bus reset
	 * for the changes to take place.  When the bus reset is
	 * detected, the controller loads the new values for the
	 * ConfigRomHeader and BusOptions registers from the specified
	 * config rom and loads ConfigROMmap from the ConfigROMmapNext
	 * shadow register. All automatically and atomically.
	 *
	 * Now, there's a twist to this story.  The automatic load of
	 * ConfigRomHeader and BusOptions doesn't honor the
	 * noByteSwapData bit, so with a be32 config rom, the
	 * controller will load be32 values in to these registers
	 * during the atomic update, even on litte endian
	 * architectures.  The workaround we use is to put a 0 in the
	 * header quadlet; 0 is endian agnostic and means that the
	 * config rom isn't ready yet.  In the bus reset tasklet we
	 * then set up the real values for the two registers.
	 *
	 * We use ohci->lock to avoid racing with the code that sets
	 * ohci->next_config_rom to NULL (see bus_reset_work).
	 */

	next_config_rom = dmam_alloc_coherent(ohci->card.device, CONFIG_ROM_SIZE,
					      &next_config_rom_bus, GFP_KERNEL);
	if (next_config_rom == NULL)
		return -ENOMEM;

	spin_lock_irq(&ohci->lock);

	/*
	 * If there is not an already pending config_rom update,
	 * push our new allocation into the ohci->next_config_rom
	 * and then mark the local variable as null so that we
	 * won't deallocate the new buffer.
	 *
	 * OTOH, if there is a pending config_rom update, just
	 * use that buffer with the new config_rom data, and
	 * let this routine free the unused DMA allocation.
	 */

	if (ohci->next_config_rom == NULL) {
		ohci->next_config_rom = next_config_rom;
		ohci->next_config_rom_bus = next_config_rom_bus;
		next_config_rom = NULL;
	}

	copy_config_rom(ohci->next_config_rom, config_rom, length);

	ohci->next_header = config_rom[0];
	ohci->next_config_rom[0] = 0;

	reg_write(ohci, OHCI1394_ConfigROMmap, ohci->next_config_rom_bus);

	spin_unlock_irq(&ohci->lock);

	/* If we didn't use the DMA allocation, delete it. */
	if (next_config_rom != NULL) {
		dmam_free_coherent(ohci->card.device, CONFIG_ROM_SIZE, next_config_rom,
				   next_config_rom_bus);
	}

	/*
	 * Now initiate a bus reset to have the changes take
	 * effect. We clean up the old config rom memory and DMA
	 * mappings in the bus reset tasklet, since the OHCI
	 * controller could need to access it before the bus reset
	 * takes effect.
	 */

	fw_schedule_bus_reset(&ohci->card, true, true);

	return 0;
}

static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
{
	struct fw_ohci *ohci = fw_ohci(card);

	at_context_transmit(&ohci->at_request_ctx, packet);
}

static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
{
	struct fw_ohci *ohci = fw_ohci(card);

	at_context_transmit(&ohci->at_response_ctx, packet);
}

static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
{
	struct fw_ohci *ohci = fw_ohci(card);
	struct context *ctx = &ohci->at_request_ctx;
	struct driver_data *driver_data = packet->driver_data;
	int ret = -ENOENT;

	tasklet_disable_in_atomic(&ctx->tasklet);

	if (packet->ack != 0)
		goto out;

	if (packet->payload_mapped)
		dma_unmap_single(ohci->card.device, packet->payload_bus,
				 packet->payload_length, DMA_TO_DEVICE);

	log_ar_at_event(ohci, 'T', packet->speed, packet->header, 0x20);
	driver_data->packet = NULL;
	packet->ack = RCODE_CANCELLED;

	// Timestamping on behalf of the hardware.
	packet->timestamp = cycle_time_to_ohci_tstamp(get_cycle_time(ohci));

	packet->callback(packet, &ohci->card, packet->ack);
	ret = 0;
 out:
	tasklet_enable(&ctx->tasklet);

	return ret;
}

static int ohci_enable_phys_dma(struct fw_card *card,
				int node_id, int generation)
{
	struct fw_ohci *ohci = fw_ohci(card);
	unsigned long flags;
	int n, ret = 0;

	if (param_remote_dma)
		return 0;

	/*
	 * FIXME:  Make sure this bitmask is cleared when we clear the busReset
	 * interrupt bit.  Clear physReqResourceAllBuses on bus reset.
	 */

	spin_lock_irqsave(&ohci->lock, flags);

	if (ohci->generation != generation) {
		ret = -ESTALE;
		goto out;
	}

	/*
	 * Note, if the node ID contains a non-local bus ID, physical DMA is
	 * enabled for _all_ nodes on remote buses.
	 */

	n = (node_id & 0xffc0) == LOCAL_BUS ? node_id & 0x3f : 63;
	if (n < 32)
		reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << n);
	else
		reg_write(ohci, OHCI1394_PhyReqFilterHiSet, 1 << (n - 32));

	flush_writes(ohci);
 out:
	spin_unlock_irqrestore(&ohci->lock, flags);

	return ret;
}

static u32 ohci_read_csr(struct fw_card *card, int csr_offset)
{
	struct fw_ohci *ohci = fw_ohci(card);
	unsigned long flags;
	u32 value;

	switch (csr_offset) {
	case CSR_STATE_CLEAR:
	case CSR_STATE_SET:
		if (ohci->is_root &&
		    (reg_read(ohci, OHCI1394_LinkControlSet) &
		     OHCI1394_LinkControl_cycleMaster))
			value = CSR_STATE_BIT_CMSTR;
		else
			value = 0;
		if (ohci->csr_state_setclear_abdicate)
			value |= CSR_STATE_BIT_ABDICATE;

		return value;

	case CSR_NODE_IDS:
		return reg_read(ohci, OHCI1394_NodeID) << 16;

	case CSR_CYCLE_TIME:
		return get_cycle_time(ohci);

	case CSR_BUS_TIME:
		/*
		 * We might be called just after the cycle timer has wrapped
		 * around but just before the cycle64Seconds handler, so we
		 * better check here, too, if the bus time needs to be updated.
		 */
		spin_lock_irqsave(&ohci->lock, flags);
		value = update_bus_time(ohci);
		spin_unlock_irqrestore(&ohci->lock, flags);
		return value;

	case CSR_BUSY_TIMEOUT:
		value = reg_read(ohci, OHCI1394_ATRetries);
		return (value >> 4) & 0x0ffff00f;

	case CSR_PRIORITY_BUDGET:
		return (reg_read(ohci, OHCI1394_FairnessControl) & 0x3f) |
			(ohci->pri_req_max << 8);

	default:
		WARN_ON(1);
		return 0;
	}
}

static void ohci_write_csr(struct fw_card *card, int csr_offset, u32 value)
{
	struct fw_ohci *ohci = fw_ohci(card);
	unsigned long flags;

	switch (csr_offset) {
	case CSR_STATE_CLEAR:
		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
			reg_write(ohci, OHCI1394_LinkControlClear,
				  OHCI1394_LinkControl_cycleMaster);
			flush_writes(ohci);
		}
		if (value & CSR_STATE_BIT_ABDICATE)
			ohci->csr_state_setclear_abdicate = false;
		break;

	case CSR_STATE_SET:
		if ((value & CSR_STATE_BIT_CMSTR) && ohci->is_root) {
			reg_write(ohci, OHCI1394_LinkControlSet,
				  OHCI1394_LinkControl_cycleMaster);
			flush_writes(ohci);
		}
		if (value & CSR_STATE_BIT_ABDICATE)
			ohci->csr_state_setclear_abdicate = true;
		break;

	case CSR_NODE_IDS:
		reg_write(ohci, OHCI1394_NodeID, value >> 16);
		flush_writes(ohci);
		break;

	case CSR_CYCLE_TIME:
		reg_write(ohci, OHCI1394_IsochronousCycleTimer, value);
		reg_write(ohci, OHCI1394_IntEventSet,
			  OHCI1394_cycleInconsistent);
		flush_writes(ohci);
		break;

	case CSR_BUS_TIME:
		spin_lock_irqsave(&ohci->lock, flags);
		ohci->bus_time = (update_bus_time(ohci) & 0x40) |
		                 (value & ~0x7f);
		spin_unlock_irqrestore(&ohci->lock, flags);
		break;

	case CSR_BUSY_TIMEOUT:
		value = (value & 0xf) | ((value & 0xf) << 4) |
			((value & 0xf) << 8) | ((value & 0x0ffff000) << 4);
		reg_write(ohci, OHCI1394_ATRetries, value);
		flush_writes(ohci);
		break;

	case CSR_PRIORITY_BUDGET:
		reg_write(ohci, OHCI1394_FairnessControl, value & 0x3f);
		flush_writes(ohci);
		break;

	default:
		WARN_ON(1);
		break;
	}
}

static void flush_iso_completions(struct iso_context *ctx)
{
	ctx->base.callback.sc(&ctx->base, ctx->last_timestamp,
			      ctx->header_length, ctx->header,
			      ctx->base.callback_data);
	ctx->header_length = 0;
}

static void copy_iso_headers(struct iso_context *ctx, const u32 *dma_hdr)
{
	u32 *ctx_hdr;

	if (ctx->header_length + ctx->base.header_size > PAGE_SIZE) {
		if (ctx->base.drop_overflow_headers)
			return;
		flush_iso_completions(ctx);
	}

	ctx_hdr = ctx->header + ctx->header_length;
	ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);

	/*
	 * The two iso header quadlets are byteswapped to little
	 * endian by the controller, but we want to present them
	 * as big endian for consistency with the bus endianness.
	 */
	if (ctx->base.header_size > 0)
		ctx_hdr[0] = swab32(dma_hdr[1]); /* iso packet header */
	if (ctx->base.header_size > 4)
		ctx_hdr[1] = swab32(dma_hdr[0]); /* timestamp */
	if (ctx->base.header_size > 8)
		memcpy(&ctx_hdr[2], &dma_hdr[2], ctx->base.header_size - 8);
	ctx->header_length += ctx->base.header_size;
}

static int handle_ir_packet_per_buffer(struct context *context,
				       struct descriptor *d,
				       struct descriptor *last)
{
	struct iso_context *ctx =
		container_of(context, struct iso_context, context);
	struct descriptor *pd;
	u32 buffer_dma;

	for (pd = d; pd <= last; pd++)
		if (pd->transfer_status)
			break;
	if (pd > last)
		/* Descriptor(s) not done yet, stop iteration */
		return 0;

	while (!(d->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))) {
		d++;
		buffer_dma = le32_to_cpu(d->data_address);
		dma_sync_single_range_for_cpu(context->ohci->card.device,
					      buffer_dma & PAGE_MASK,
					      buffer_dma & ~PAGE_MASK,
					      le16_to_cpu(d->req_count),
					      DMA_FROM_DEVICE);
	}

	copy_iso_headers(ctx, (u32 *) (last + 1));

	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
		flush_iso_completions(ctx);

	return 1;
}

/* d == last because each descriptor block is only a single descriptor. */
static int handle_ir_buffer_fill(struct context *context,
				 struct descriptor *d,
				 struct descriptor *last)
{
	struct iso_context *ctx =
		container_of(context, struct iso_context, context);
	unsigned int req_count, res_count, completed;
	u32 buffer_dma;

	req_count = le16_to_cpu(last->req_count);
	res_count = le16_to_cpu(READ_ONCE(last->res_count));
	completed = req_count - res_count;
	buffer_dma = le32_to_cpu(last->data_address);

	if (completed > 0) {
		ctx->mc_buffer_bus = buffer_dma;
		ctx->mc_completed = completed;
	}

	if (res_count != 0)
		/* Descriptor(s) not done yet, stop iteration */
		return 0;

	dma_sync_single_range_for_cpu(context->ohci->card.device,
				      buffer_dma & PAGE_MASK,
				      buffer_dma & ~PAGE_MASK,
				      completed, DMA_FROM_DEVICE);

	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS)) {
		ctx->base.callback.mc(&ctx->base,
				      buffer_dma + completed,
				      ctx->base.callback_data);
		ctx->mc_completed = 0;
	}

	return 1;
}

static void flush_ir_buffer_fill(struct iso_context *ctx)
{
	dma_sync_single_range_for_cpu(ctx->context.ohci->card.device,
				      ctx->mc_buffer_bus & PAGE_MASK,
				      ctx->mc_buffer_bus & ~PAGE_MASK,
				      ctx->mc_completed, DMA_FROM_DEVICE);

	ctx->base.callback.mc(&ctx->base,
			      ctx->mc_buffer_bus + ctx->mc_completed,
			      ctx->base.callback_data);
	ctx->mc_completed = 0;
}

static inline void sync_it_packet_for_cpu(struct context *context,
					  struct descriptor *pd)
{
	__le16 control;
	u32 buffer_dma;

	/* only packets beginning with OUTPUT_MORE* have data buffers */
	if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
		return;

	/* skip over the OUTPUT_MORE_IMMEDIATE descriptor */
	pd += 2;

	/*
	 * If the packet has a header, the first OUTPUT_MORE/LAST descriptor's
	 * data buffer is in the context program's coherent page and must not
	 * be synced.
	 */
	if ((le32_to_cpu(pd->data_address) & PAGE_MASK) ==
	    (context->current_bus          & PAGE_MASK)) {
		if (pd->control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS))
			return;
		pd++;
	}

	do {
		buffer_dma = le32_to_cpu(pd->data_address);
		dma_sync_single_range_for_cpu(context->ohci->card.device,
					      buffer_dma & PAGE_MASK,
					      buffer_dma & ~PAGE_MASK,
					      le16_to_cpu(pd->req_count),
					      DMA_TO_DEVICE);
		control = pd->control;
		pd++;
	} while (!(control & cpu_to_le16(DESCRIPTOR_BRANCH_ALWAYS)));
}

static int handle_it_packet(struct context *context,
			    struct descriptor *d,
			    struct descriptor *last)
{
	struct iso_context *ctx =
		container_of(context, struct iso_context, context);
	struct descriptor *pd;
	__be32 *ctx_hdr;

	for (pd = d; pd <= last; pd++)
		if (pd->transfer_status)
			break;
	if (pd > last)
		/* Descriptor(s) not done yet, stop iteration */
		return 0;

	sync_it_packet_for_cpu(context, d);

	if (ctx->header_length + 4 > PAGE_SIZE) {
		if (ctx->base.drop_overflow_headers)
			return 1;
		flush_iso_completions(ctx);
	}

	ctx_hdr = ctx->header + ctx->header_length;
	ctx->last_timestamp = le16_to_cpu(last->res_count);
	/* Present this value as big-endian to match the receive code */
	*ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
			       le16_to_cpu(pd->res_count));
	ctx->header_length += 4;

	if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
		flush_iso_completions(ctx);

	return 1;
}

static void set_multichannel_mask(struct fw_ohci *ohci, u64 channels)
{
	u32 hi = channels >> 32, lo = channels;

	reg_write(ohci, OHCI1394_IRMultiChanMaskHiClear, ~hi);
	reg_write(ohci, OHCI1394_IRMultiChanMaskLoClear, ~lo);
	reg_write(ohci, OHCI1394_IRMultiChanMaskHiSet, hi);
	reg_write(ohci, OHCI1394_IRMultiChanMaskLoSet, lo);
	ohci->mc_channels = channels;
}

static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
				int type, int channel, size_t header_size)
{
	struct fw_ohci *ohci = fw_ohci(card);
	struct iso_context *ctx;
	descriptor_callback_t callback;
	u64 *channels;
	u32 *mask, regs;
	int index, ret = -EBUSY;

	spin_lock_irq(&ohci->lock);

	switch (type) {
	case FW_ISO_CONTEXT_TRANSMIT:
		mask     = &ohci->it_context_mask;
		callback = handle_it_packet;
		index    = ffs(*mask) - 1;
		if (index >= 0) {
			*mask &= ~(1 << index);
			regs = OHCI1394_IsoXmitContextBase(index);
			ctx  = &ohci->it_context_list[index];
		}
		break;

	case FW_ISO_CONTEXT_RECEIVE:
		channels = &ohci->ir_context_channels;
		mask     = &ohci->ir_context_mask;
		callback = handle_ir_packet_per_buffer;
		index    = *channels & 1ULL << channel ? ffs(*mask) - 1 : -1;
		if (index >= 0) {
			*channels &= ~(1ULL << channel);
			*mask     &= ~(1 << index);
			regs = OHCI1394_IsoRcvContextBase(index);
			ctx  = &ohci->ir_context_list[index];
		}
		break;

	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
		mask     = &ohci->ir_context_mask;
		callback = handle_ir_buffer_fill;
		index    = !ohci->mc_allocated ? ffs(*mask) - 1 : -1;
		if (index >= 0) {
			ohci->mc_allocated = true;
			*mask &= ~(1 << index);
			regs = OHCI1394_IsoRcvContextBase(index);
			ctx  = &ohci->ir_context_list[index];
		}
		break;

	default:
		index = -1;
		ret = -ENOSYS;
	}

	spin_unlock_irq(&ohci->lock);

	if (index < 0)
		return ERR_PTR(ret);

	memset(ctx, 0, sizeof(*ctx));
	ctx->header_length = 0;
	ctx->header = (void *) __get_free_page(GFP_KERNEL);
	if (ctx->header == NULL) {
		ret = -ENOMEM;
		goto out;
	}
	ret = context_init(&ctx->context, ohci, regs, callback);
	if (ret < 0)
		goto out_with_header;

	if (type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL) {
		set_multichannel_mask(ohci, 0);
		ctx->mc_completed = 0;
	}

	return &ctx->base;

 out_with_header:
	free_page((unsigned long)ctx->header);
 out:
	spin_lock_irq(&ohci->lock);

	switch (type) {
	case FW_ISO_CONTEXT_RECEIVE:
		*channels |= 1ULL << channel;
		break;

	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
		ohci->mc_allocated = false;
		break;
	}
	*mask |= 1 << index;

	spin_unlock_irq(&ohci->lock);

	return ERR_PTR(ret);
}

static int ohci_start_iso(struct fw_iso_context *base,
			  s32 cycle, u32 sync, u32 tags)
{
	struct iso_context *ctx = container_of(base, struct iso_context, base);
	struct fw_ohci *ohci = ctx->context.ohci;
	u32 control = IR_CONTEXT_ISOCH_HEADER, match;
	int index;

	/* the controller cannot start without any queued packets */
	if (ctx->context.last->branch_address == 0)
		return -ENODATA;

	switch (ctx->base.type) {
	case FW_ISO_CONTEXT_TRANSMIT:
		index = ctx - ohci->it_context_list;
		match = 0;
		if (cycle >= 0)
			match = IT_CONTEXT_CYCLE_MATCH_ENABLE |
				(cycle & 0x7fff) << 16;

		reg_write(ohci, OHCI1394_IsoXmitIntEventClear, 1 << index);
		reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
		context_run(&ctx->context, match);
		break;

	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
		control |= IR_CONTEXT_BUFFER_FILL|IR_CONTEXT_MULTI_CHANNEL_MODE;
		fallthrough;
	case FW_ISO_CONTEXT_RECEIVE:
		index = ctx - ohci->ir_context_list;
		match = (tags << 28) | (sync << 8) | ctx->base.channel;
		if (cycle >= 0) {
			match |= (cycle & 0x07fff) << 12;
			control |= IR_CONTEXT_CYCLE_MATCH_ENABLE;
		}

		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
		reg_write(ohci, CONTEXT_MATCH(ctx->context.regs), match);
		context_run(&ctx->context, control);

		ctx->sync = sync;
		ctx->tags = tags;

		break;
	}

	return 0;
}

static int ohci_stop_iso(struct fw_iso_context *base)
{
	struct fw_ohci *ohci = fw_ohci(base->card);
	struct iso_context *ctx = container_of(base, struct iso_context, base);
	int index;

	switch (ctx->base.type) {
	case FW_ISO_CONTEXT_TRANSMIT:
		index = ctx - ohci->it_context_list;
		reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
		break;

	case FW_ISO_CONTEXT_RECEIVE:
	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
		index = ctx - ohci->ir_context_list;
		reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
		break;
	}
	flush_writes(ohci);
	context_stop(&ctx->context);
	tasklet_kill(&ctx->context.tasklet);

	return 0;
}

static void ohci_free_iso_context(struct fw_iso_context *base)
{
	struct fw_ohci *ohci = fw_ohci(base->card);
	struct iso_context *ctx = container_of(base, struct iso_context, base);
	unsigned long flags;
	int index;

	ohci_stop_iso(base);
	context_release(&ctx->context);
	free_page((unsigned long)ctx->header);

	spin_lock_irqsave(&ohci->lock, flags);

	switch (base->type) {
	case FW_ISO_CONTEXT_TRANSMIT:
		index = ctx - ohci->it_context_list;
		ohci->it_context_mask |= 1 << index;
		break;

	case FW_ISO_CONTEXT_RECEIVE:
		index = ctx - ohci->ir_context_list;
		ohci->ir_context_mask |= 1 << index;
		ohci->ir_context_channels |= 1ULL << base->channel;
		break;

	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
		index = ctx - ohci->ir_context_list;
		ohci->ir_context_mask |= 1 << index;
		ohci->ir_context_channels |= ohci->mc_channels;
		ohci->mc_channels = 0;
		ohci->mc_allocated = false;
		break;
	}

	spin_unlock_irqrestore(&ohci->lock, flags);
}

static int ohci_set_iso_channels(struct fw_iso_context *base, u64 *channels)
{
	struct fw_ohci *ohci = fw_ohci(base->card);
	unsigned long flags;
	int ret;

	switch (base->type) {
	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:

		spin_lock_irqsave(&ohci->lock, flags);

		/* Don't allow multichannel to grab other contexts' channels. */
		if (~ohci->ir_context_channels & ~ohci->mc_channels & *channels) {
			*channels = ohci->ir_context_channels;
			ret = -EBUSY;
		} else {
			set_multichannel_mask(ohci, *channels);
			ret = 0;
		}

		spin_unlock_irqrestore(&ohci->lock, flags);

		break;
	default:
		ret = -EINVAL;
	}

	return ret;
}

#ifdef CONFIG_PM
static void ohci_resume_iso_dma(struct fw_ohci *ohci)
{
	int i;
	struct iso_context *ctx;

	for (i = 0 ; i < ohci->n_ir ; i++) {
		ctx = &ohci->ir_context_list[i];
		if (ctx->context.running)
			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
	}

	for (i = 0 ; i < ohci->n_it ; i++) {
		ctx = &ohci->it_context_list[i];
		if (ctx->context.running)
			ohci_start_iso(&ctx->base, 0, ctx->sync, ctx->tags);
	}
}
#endif

static int queue_iso_transmit(struct iso_context *ctx,
			      struct fw_iso_packet *packet,
			      struct fw_iso_buffer *buffer,
			      unsigned long payload)
{
	struct descriptor *d, *last, *pd;
	struct fw_iso_packet *p;
	__le32 *header;
	dma_addr_t d_bus, page_bus;
	u32 z, header_z, payload_z, irq;
	u32 payload_index, payload_end_index, next_page_index;
	int page, end_page, i, length, offset;

	p = packet;
	payload_index = payload;

	if (p->skip)
		z = 1;
	else
		z = 2;
	if (p->header_length > 0)
		z++;

	/* Determine the first page the payload isn't contained in. */
	end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
	if (p->payload_length > 0)
		payload_z = end_page - (payload_index >> PAGE_SHIFT);
	else
		payload_z = 0;

	z += payload_z;

	/* Get header size in number of descriptors. */
	header_z = DIV_ROUND_UP(p->header_length, sizeof(*d));

	d = context_get_descriptors(&ctx->context, z + header_z, &d_bus);
	if (d == NULL)
		return -ENOMEM;

	if (!p->skip) {
		d[0].control   = cpu_to_le16(DESCRIPTOR_KEY_IMMEDIATE);
		d[0].req_count = cpu_to_le16(8);
		/*
		 * Link the skip address to this descriptor itself.  This causes
		 * a context to skip a cycle whenever lost cycles or FIFO
		 * overruns occur, without dropping the data.  The application
		 * should then decide whether this is an error condition or not.
		 * FIXME:  Make the context's cycle-lost behaviour configurable?
		 */
		d[0].branch_address = cpu_to_le32(d_bus | z);

		header = (__le32 *) &d[1];
		header[0] = cpu_to_le32(IT_HEADER_SY(p->sy) |
					IT_HEADER_TAG(p->tag) |
					IT_HEADER_TCODE(TCODE_STREAM_DATA) |
					IT_HEADER_CHANNEL(ctx->base.channel) |
					IT_HEADER_SPEED(ctx->base.speed));
		header[1] =
			cpu_to_le32(IT_HEADER_DATA_LENGTH(p->header_length +
							  p->payload_length));
	}

	if (p->header_length > 0) {
		d[2].req_count    = cpu_to_le16(p->header_length);
		d[2].data_address = cpu_to_le32(d_bus + z * sizeof(*d));
		memcpy(&d[z], p->header, p->header_length);
	}

	pd = d + z - payload_z;
	payload_end_index = payload_index + p->payload_length;
	for (i = 0; i < payload_z; i++) {
		page               = payload_index >> PAGE_SHIFT;
		offset             = payload_index & ~PAGE_MASK;
		next_page_index    = (page + 1) << PAGE_SHIFT;
		length             =
			min(next_page_index, payload_end_index) - payload_index;
		pd[i].req_count    = cpu_to_le16(length);

		page_bus = page_private(buffer->pages[page]);
		pd[i].data_address = cpu_to_le32(page_bus + offset);

		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
						 page_bus, offset, length,
						 DMA_TO_DEVICE);

		payload_index += length;
	}

	if (p->interrupt)
		irq = DESCRIPTOR_IRQ_ALWAYS;
	else
		irq = DESCRIPTOR_NO_IRQ;

	last = z == 2 ? d : d + z - 1;
	last->control |= cpu_to_le16(DESCRIPTOR_OUTPUT_LAST |
				     DESCRIPTOR_STATUS |
				     DESCRIPTOR_BRANCH_ALWAYS |
				     irq);

	context_append(&ctx->context, d, z, header_z);

	return 0;
}

static int queue_iso_packet_per_buffer(struct iso_context *ctx,
				       struct fw_iso_packet *packet,
				       struct fw_iso_buffer *buffer,
				       unsigned long payload)
{
	struct device *device = ctx->context.ohci->card.device;
	struct descriptor *d, *pd;
	dma_addr_t d_bus, page_bus;
	u32 z, header_z, rest;
	int i, j, length;
	int page, offset, packet_count, header_size, payload_per_buffer;

	/*
	 * The OHCI controller puts the isochronous header and trailer in the
	 * buffer, so we need at least 8 bytes.
	 */
	packet_count = packet->header_length / ctx->base.header_size;
	header_size  = max(ctx->base.header_size, (size_t)8);

	/* Get header size in number of descriptors. */
	header_z = DIV_ROUND_UP(header_size, sizeof(*d));
	page     = payload >> PAGE_SHIFT;
	offset   = payload & ~PAGE_MASK;
	payload_per_buffer = packet->payload_length / packet_count;

	for (i = 0; i < packet_count; i++) {
		/* d points to the header descriptor */
		z = DIV_ROUND_UP(payload_per_buffer + offset, PAGE_SIZE) + 1;
		d = context_get_descriptors(&ctx->context,
				z + header_z, &d_bus);
		if (d == NULL)
			return -ENOMEM;

		d->control      = cpu_to_le16(DESCRIPTOR_STATUS |
					      DESCRIPTOR_INPUT_MORE);
		if (packet->skip && i == 0)
			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
		d->req_count    = cpu_to_le16(header_size);
		d->res_count    = d->req_count;
		d->transfer_status = 0;
		d->data_address = cpu_to_le32(d_bus + (z * sizeof(*d)));

		rest = payload_per_buffer;
		pd = d;
		for (j = 1; j < z; j++) {
			pd++;
			pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
						  DESCRIPTOR_INPUT_MORE);

			if (offset + rest < PAGE_SIZE)
				length = rest;
			else
				length = PAGE_SIZE - offset;
			pd->req_count = cpu_to_le16(length);
			pd->res_count = pd->req_count;
			pd->transfer_status = 0;

			page_bus = page_private(buffer->pages[page]);
			pd->data_address = cpu_to_le32(page_bus + offset);

			dma_sync_single_range_for_device(device, page_bus,
							 offset, length,
							 DMA_FROM_DEVICE);

			offset = (offset + length) & ~PAGE_MASK;
			rest -= length;
			if (offset == 0)
				page++;
		}
		pd->control = cpu_to_le16(DESCRIPTOR_STATUS |
					  DESCRIPTOR_INPUT_LAST |
					  DESCRIPTOR_BRANCH_ALWAYS);
		if (packet->interrupt && i == packet_count - 1)
			pd->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);

		context_append(&ctx->context, d, z, header_z);
	}

	return 0;
}

static int queue_iso_buffer_fill(struct iso_context *ctx,
				 struct fw_iso_packet *packet,
				 struct fw_iso_buffer *buffer,
				 unsigned long payload)
{
	struct descriptor *d;
	dma_addr_t d_bus, page_bus;
	int page, offset, rest, z, i, length;

	page   = payload >> PAGE_SHIFT;
	offset = payload & ~PAGE_MASK;
	rest   = packet->payload_length;

	/* We need one descriptor for each page in the buffer. */
	z = DIV_ROUND_UP(offset + rest, PAGE_SIZE);

	if (WARN_ON(offset & 3 || rest & 3 || page + z > buffer->page_count))
		return -EFAULT;

	for (i = 0; i < z; i++) {
		d = context_get_descriptors(&ctx->context, 1, &d_bus);
		if (d == NULL)
			return -ENOMEM;

		d->control = cpu_to_le16(DESCRIPTOR_INPUT_MORE |
					 DESCRIPTOR_BRANCH_ALWAYS);
		if (packet->skip && i == 0)
			d->control |= cpu_to_le16(DESCRIPTOR_WAIT);
		if (packet->interrupt && i == z - 1)
			d->control |= cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS);

		if (offset + rest < PAGE_SIZE)
			length = rest;
		else
			length = PAGE_SIZE - offset;
		d->req_count = cpu_to_le16(length);
		d->res_count = d->req_count;
		d->transfer_status = 0;

		page_bus = page_private(buffer->pages[page]);
		d->data_address = cpu_to_le32(page_bus + offset);

		dma_sync_single_range_for_device(ctx->context.ohci->card.device,
						 page_bus, offset, length,
						 DMA_FROM_DEVICE);

		rest -= length;
		offset = 0;
		page++;

		context_append(&ctx->context, d, 1, 0);
	}

	return 0;
}

static int ohci_queue_iso(struct fw_iso_context *base,
			  struct fw_iso_packet *packet,
			  struct fw_iso_buffer *buffer,
			  unsigned long payload)
{
	struct iso_context *ctx = container_of(base, struct iso_context, base);
	unsigned long flags;
	int ret = -ENOSYS;

	spin_lock_irqsave(&ctx->context.ohci->lock, flags);
	switch (base->type) {
	case FW_ISO_CONTEXT_TRANSMIT:
		ret = queue_iso_transmit(ctx, packet, buffer, payload);
		break;
	case FW_ISO_CONTEXT_RECEIVE:
		ret = queue_iso_packet_per_buffer(ctx, packet, buffer, payload);
		break;
	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
		ret = queue_iso_buffer_fill(ctx, packet, buffer, payload);
		break;
	}
	spin_unlock_irqrestore(&ctx->context.ohci->lock, flags);

	return ret;
}

static void ohci_flush_queue_iso(struct fw_iso_context *base)
{
	struct context *ctx =
			&container_of(base, struct iso_context, base)->context;

	reg_write(ctx->ohci, CONTROL_SET(ctx->regs), CONTEXT_WAKE);
}

static int ohci_flush_iso_completions(struct fw_iso_context *base)
{
	struct iso_context *ctx = container_of(base, struct iso_context, base);
	int ret = 0;

	tasklet_disable_in_atomic(&ctx->context.tasklet);

	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
		context_tasklet((unsigned long)&ctx->context);

		switch (base->type) {
		case FW_ISO_CONTEXT_TRANSMIT:
		case FW_ISO_CONTEXT_RECEIVE:
			if (ctx->header_length != 0)
				flush_iso_completions(ctx);
			break;
		case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
			if (ctx->mc_completed != 0)
				flush_ir_buffer_fill(ctx);
			break;
		default:
			ret = -ENOSYS;
		}

		clear_bit_unlock(0, &ctx->flushing_completions);
		smp_mb__after_atomic();
	}

	tasklet_enable(&ctx->context.tasklet);

	return ret;
}

static const struct fw_card_driver ohci_driver = {
	.enable			= ohci_enable,
	.read_phy_reg		= ohci_read_phy_reg,
	.update_phy_reg		= ohci_update_phy_reg,
	.set_config_rom		= ohci_set_config_rom,
	.send_request		= ohci_send_request,
	.send_response		= ohci_send_response,
	.cancel_packet		= ohci_cancel_packet,
	.enable_phys_dma	= ohci_enable_phys_dma,
	.read_csr		= ohci_read_csr,
	.write_csr		= ohci_write_csr,

	.allocate_iso_context	= ohci_allocate_iso_context,
	.free_iso_context	= ohci_free_iso_context,
	.set_iso_channels	= ohci_set_iso_channels,
	.queue_iso		= ohci_queue_iso,
	.flush_queue_iso	= ohci_flush_queue_iso,
	.flush_iso_completions	= ohci_flush_iso_completions,
	.start_iso		= ohci_start_iso,
	.stop_iso		= ohci_stop_iso,
};

#ifdef CONFIG_PPC_PMAC
static void pmac_ohci_on(struct pci_dev *dev)
{
	if (machine_is(powermac)) {
		struct device_node *ofn = pci_device_to_OF_node(dev);

		if (ofn) {
			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 1);
			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 1);
		}
	}
}

static void pmac_ohci_off(struct pci_dev *dev)
{
	if (machine_is(powermac)) {
		struct device_node *ofn = pci_device_to_OF_node(dev);

		if (ofn) {
			pmac_call_feature(PMAC_FTR_1394_ENABLE, ofn, 0, 0);
			pmac_call_feature(PMAC_FTR_1394_CABLE_POWER, ofn, 0, 0);
		}
	}
}
#else
static inline void pmac_ohci_on(struct pci_dev *dev) {}
static inline void pmac_ohci_off(struct pci_dev *dev) {}
#endif /* CONFIG_PPC_PMAC */

static void release_ohci(struct device *dev, void *data)
{
	struct pci_dev *pdev = to_pci_dev(dev);
	struct fw_ohci *ohci = pci_get_drvdata(pdev);

	pmac_ohci_off(pdev);

	ar_context_release(&ohci->ar_response_ctx);
	ar_context_release(&ohci->ar_request_ctx);

	dev_notice(dev, "removed fw-ohci device\n");
}

static int pci_probe(struct pci_dev *dev,
			       const struct pci_device_id *ent)
{
	struct fw_ohci *ohci;
	u32 bus_options, max_receive, link_speed, version;
	u64 guid;
	int i, err;
	size_t size;

	if (dev->vendor == PCI_VENDOR_ID_PINNACLE_SYSTEMS) {
		dev_err(&dev->dev, "Pinnacle MovieBoard is not yet supported\n");
		return -ENOSYS;
	}

	ohci = devres_alloc(release_ohci, sizeof(*ohci), GFP_KERNEL);
	if (ohci == NULL)
		return -ENOMEM;
	fw_card_initialize(&ohci->card, &ohci_driver, &dev->dev);
	pci_set_drvdata(dev, ohci);
	pmac_ohci_on(dev);
	devres_add(&dev->dev, ohci);

	err = pcim_enable_device(dev);
	if (err) {
		dev_err(&dev->dev, "failed to enable OHCI hardware\n");
		return err;
	}

	pci_set_master(dev);
	pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);

	spin_lock_init(&ohci->lock);
	mutex_init(&ohci->phy_reg_mutex);

	INIT_WORK(&ohci->bus_reset_work, bus_reset_work);

	if (!(pci_resource_flags(dev, 0) & IORESOURCE_MEM) ||
	    pci_resource_len(dev, 0) < OHCI1394_REGISTER_SIZE) {
		ohci_err(ohci, "invalid MMIO resource\n");
		return -ENXIO;
	}

	err = pcim_iomap_regions(dev, 1 << 0, ohci_driver_name);
	if (err) {
		ohci_err(ohci, "request and map MMIO resource unavailable\n");
		return -ENXIO;
	}
	ohci->registers = pcim_iomap_table(dev)[0];

	for (i = 0; i < ARRAY_SIZE(ohci_quirks); i++)
		if ((ohci_quirks[i].vendor == dev->vendor) &&
		    (ohci_quirks[i].device == (unsigned short)PCI_ANY_ID ||
		     ohci_quirks[i].device == dev->device) &&
		    (ohci_quirks[i].revision == (unsigned short)PCI_ANY_ID ||
		     ohci_quirks[i].revision >= dev->revision)) {
			ohci->quirks = ohci_quirks[i].flags;
			break;
		}
	if (param_quirks)
		ohci->quirks = param_quirks;

	if (detect_vt630x_with_asm1083_on_amd_ryzen_machine(dev))
		ohci->quirks |= QUIRK_REBOOT_BY_CYCLE_TIMER_READ;

	/*
	 * Because dma_alloc_coherent() allocates at least one page,
	 * we save space by using a common buffer for the AR request/
	 * response descriptors and the self IDs buffer.
	 */
	BUILD_BUG_ON(AR_BUFFERS * sizeof(struct descriptor) > PAGE_SIZE/4);
	BUILD_BUG_ON(SELF_ID_BUF_SIZE > PAGE_SIZE/2);
	ohci->misc_buffer = dmam_alloc_coherent(&dev->dev, PAGE_SIZE, &ohci->misc_buffer_bus,
						GFP_KERNEL);
	if (!ohci->misc_buffer)
		return -ENOMEM;

	err = ar_context_init(&ohci->ar_request_ctx, ohci, 0,
			      OHCI1394_AsReqRcvContextControlSet);
	if (err < 0)
		return err;

	err = ar_context_init(&ohci->ar_response_ctx, ohci, PAGE_SIZE/4,
			      OHCI1394_AsRspRcvContextControlSet);
	if (err < 0)
		return err;

	err = context_init(&ohci->at_request_ctx, ohci,
			   OHCI1394_AsReqTrContextControlSet, handle_at_packet);
	if (err < 0)
		return err;

	err = context_init(&ohci->at_response_ctx, ohci,
			   OHCI1394_AsRspTrContextControlSet, handle_at_packet);
	if (err < 0)
		return err;

	reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
	ohci->ir_context_channels = ~0ULL;
	ohci->ir_context_support = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
	reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
	ohci->ir_context_mask = ohci->ir_context_support;
	ohci->n_ir = hweight32(ohci->ir_context_mask);
	size = sizeof(struct iso_context) * ohci->n_ir;
	ohci->ir_context_list = devm_kzalloc(&dev->dev, size, GFP_KERNEL);
	if (!ohci->ir_context_list)
		return -ENOMEM;

	reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
	ohci->it_context_support = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
	/* JMicron JMB38x often shows 0 at first read, just ignore it */
	if (!ohci->it_context_support) {
		ohci_notice(ohci, "overriding IsoXmitIntMask\n");
		ohci->it_context_support = 0xf;
	}
	reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
	ohci->it_context_mask = ohci->it_context_support;
	ohci->n_it = hweight32(ohci->it_context_mask);
	size = sizeof(struct iso_context) * ohci->n_it;
	ohci->it_context_list = devm_kzalloc(&dev->dev, size, GFP_KERNEL);
	if (!ohci->it_context_list)
		return -ENOMEM;

	ohci->self_id     = ohci->misc_buffer     + PAGE_SIZE/2;
	ohci->self_id_bus = ohci->misc_buffer_bus + PAGE_SIZE/2;

	bus_options = reg_read(ohci, OHCI1394_BusOptions);
	max_receive = (bus_options >> 12) & 0xf;
	link_speed = bus_options & 0x7;
	guid = ((u64) reg_read(ohci, OHCI1394_GUIDHi) << 32) |
		reg_read(ohci, OHCI1394_GUIDLo);

	if (!(ohci->quirks & QUIRK_NO_MSI))
		pci_enable_msi(dev);
	err = devm_request_irq(&dev->dev, dev->irq, irq_handler,
			       pci_dev_msi_enabled(dev) ? 0 : IRQF_SHARED, ohci_driver_name, ohci);
	if (err < 0) {
		ohci_err(ohci, "failed to allocate interrupt %d\n", dev->irq);
		goto fail_msi;
	}

	err = fw_card_add(&ohci->card, max_receive, link_speed, guid);
	if (err)
		goto fail_msi;

	version = reg_read(ohci, OHCI1394_Version) & 0x00ff00ff;
	ohci_notice(ohci,
		    "added OHCI v%x.%x device as card %d, "
		    "%d IR + %d IT contexts, quirks 0x%x%s\n",
		    version >> 16, version & 0xff, ohci->card.index,
		    ohci->n_ir, ohci->n_it, ohci->quirks,
		    reg_read(ohci, OHCI1394_PhyUpperBound) ?
			", physUB" : "");

	return 0;

 fail_msi:
	devm_free_irq(&dev->dev, dev->irq, ohci);
	pci_disable_msi(dev);

	return err;
}

static void pci_remove(struct pci_dev *dev)
{
	struct fw_ohci *ohci = pci_get_drvdata(dev);

	/*
	 * If the removal is happening from the suspend state, LPS won't be
	 * enabled and host registers (eg., IntMaskClear) won't be accessible.
	 */
	if (reg_read(ohci, OHCI1394_HCControlSet) & OHCI1394_HCControl_LPS) {
		reg_write(ohci, OHCI1394_IntMaskClear, ~0);
		flush_writes(ohci);
	}
	cancel_work_sync(&ohci->bus_reset_work);
	fw_core_remove_card(&ohci->card);

	/*
	 * FIXME: Fail all pending packets here, now that the upper
	 * layers can't queue any more.
	 */

	software_reset(ohci);

	devm_free_irq(&dev->dev, dev->irq, ohci);
	pci_disable_msi(dev);

	dev_notice(&dev->dev, "removing fw-ohci device\n");
}

#ifdef CONFIG_PM
static int pci_suspend(struct pci_dev *dev, pm_message_t state)
{
	struct fw_ohci *ohci = pci_get_drvdata(dev);
	int err;

	software_reset(ohci);
	err = pci_save_state(dev);
	if (err) {
		ohci_err(ohci, "pci_save_state failed\n");
		return err;
	}
	err = pci_set_power_state(dev, pci_choose_state(dev, state));
	if (err)
		ohci_err(ohci, "pci_set_power_state failed with %d\n", err);
	pmac_ohci_off(dev);

	return 0;
}

static int pci_resume(struct pci_dev *dev)
{
	struct fw_ohci *ohci = pci_get_drvdata(dev);
	int err;

	pmac_ohci_on(dev);
	pci_set_power_state(dev, PCI_D0);
	pci_restore_state(dev);
	err = pci_enable_device(dev);
	if (err) {
		ohci_err(ohci, "pci_enable_device failed\n");
		return err;
	}

	/* Some systems don't setup GUID register on resume from ram  */
	if (!reg_read(ohci, OHCI1394_GUIDLo) &&
					!reg_read(ohci, OHCI1394_GUIDHi)) {
		reg_write(ohci, OHCI1394_GUIDLo, (u32)ohci->card.guid);
		reg_write(ohci, OHCI1394_GUIDHi, (u32)(ohci->card.guid >> 32));
	}

	err = ohci_enable(&ohci->card, NULL, 0);
	if (err)
		return err;

	ohci_resume_iso_dma(ohci);

	return 0;
}
#endif

static const struct pci_device_id pci_table[] = {
	{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_FIREWIRE_OHCI, ~0) },
	{ }
};

MODULE_DEVICE_TABLE(pci, pci_table);

static struct pci_driver fw_ohci_pci_driver = {
	.name		= ohci_driver_name,
	.id_table	= pci_table,
	.probe		= pci_probe,
	.remove		= pci_remove,
#ifdef CONFIG_PM
	.resume		= pci_resume,
	.suspend	= pci_suspend,
#endif
};

static int __init fw_ohci_init(void)
{
	selfid_workqueue = alloc_workqueue(KBUILD_MODNAME, WQ_MEM_RECLAIM, 0);
	if (!selfid_workqueue)
		return -ENOMEM;

	return pci_register_driver(&fw_ohci_pci_driver);
}

static void __exit fw_ohci_cleanup(void)
{
	pci_unregister_driver(&fw_ohci_pci_driver);
	destroy_workqueue(selfid_workqueue);
}

module_init(fw_ohci_init);
module_exit(fw_ohci_cleanup);

MODULE_AUTHOR("Kristian Hoegsberg <krh@bitplanet.net>");
MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
MODULE_LICENSE("GPL");

/* Provide a module alias so root-on-sbp2 initrds don't break. */
MODULE_ALIAS("ohci1394");