summaryrefslogtreecommitdiff
path: root/drivers/scsi/arm/acornscsi.c
blob: c454e44cf51c6653b8fd050c681ba64eea719b63 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
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
/*
 *  linux/drivers/acorn/scsi/acornscsi.c
 *
 *  Acorn SCSI 3 driver
 *  By R.M.King.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Abandoned using the Select and Transfer command since there were
 * some nasty races between our software and the target devices that
 * were not easy to solve, and the device errata had a lot of entries
 * for this command, some of them quite nasty...
 *
 * Changelog:
 *  26-Sep-1997	RMK	Re-jigged to use the queue module.
 *			Re-coded state machine to be based on driver
 *			state not scsi state.  Should be easier to debug.
 *			Added acornscsi_release to clean up properly.
 *			Updated proc/scsi reporting.
 *  05-Oct-1997	RMK	Implemented writing to SCSI devices.
 *  06-Oct-1997	RMK	Corrected small (non-serious) bug with the connect/
 *			reconnect race condition causing a warning message.
 *  12-Oct-1997	RMK	Added catch for re-entering interrupt routine.
 *  15-Oct-1997	RMK	Improved handling of commands.
 *  27-Jun-1998	RMK	Changed asm/delay.h to linux/delay.h.
 *  13-Dec-1998	RMK	Better abort code and command handling.  Extra state
 *			transitions added to allow dodgy devices to work.
 */
#define DEBUG_NO_WRITE	1
#define DEBUG_QUEUES	2
#define DEBUG_DMA	4
#define DEBUG_ABORT	8
#define DEBUG_DISCON	16
#define DEBUG_CONNECT	32
#define DEBUG_PHASES	64
#define DEBUG_WRITE	128
#define DEBUG_LINK	256
#define DEBUG_MESSAGES	512
#define DEBUG_RESET	1024
#define DEBUG_ALL	(DEBUG_RESET|DEBUG_MESSAGES|DEBUG_LINK|DEBUG_WRITE|\
			 DEBUG_PHASES|DEBUG_CONNECT|DEBUG_DISCON|DEBUG_ABORT|\
			 DEBUG_DMA|DEBUG_QUEUES)

/* DRIVER CONFIGURATION
 *
 * SCSI-II Tagged queue support.
 *
 * I don't have any SCSI devices that support it, so it is totally untested
 * (except to make sure that it doesn't interfere with any non-tagging
 * devices).  It is not fully implemented either - what happens when a
 * tagging device reconnects???
 *
 * You can tell if you have a device that supports tagged queueing my
 * cating (eg) /proc/scsi/acornscsi/0 and see if the SCSI revision is reported
 * as '2 TAG'.
 *
 * Also note that CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE is normally set in the config
 * scripts, but disabled here.  Once debugged, remove the #undef, otherwise to debug,
 * comment out the undef.
 */
#undef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
/*
 * SCSI-II Linked command support.
 *
 * The higher level code doesn't support linked commands yet, and so the option
 * is undef'd here.
 */
#undef CONFIG_SCSI_ACORNSCSI_LINK
/*
 * SCSI-II Synchronous transfer support.
 *
 * Tried and tested...
 *
 * SDTR_SIZE	  - maximum number of un-acknowledged bytes (0 = off, 12 = max)
 * SDTR_PERIOD	  - period of REQ signal (min=125, max=1020)
 * DEFAULT_PERIOD - default REQ period.
 */
#define SDTR_SIZE	12
#define SDTR_PERIOD	125
#define DEFAULT_PERIOD	500

/*
 * Debugging information
 *
 * DEBUG	  - bit mask from list above
 * DEBUG_TARGET   - is defined to the target number if you want to debug
 *		    a specific target. [only recon/write/dma].
 */
#define DEBUG (DEBUG_RESET|DEBUG_WRITE|DEBUG_NO_WRITE)
/* only allow writing to SCSI device 0 */
#define NO_WRITE 0xFE
/*#define DEBUG_TARGET 2*/
/*
 * Select timeout time (in 10ms units)
 *
 * This is the timeout used between the start of selection and the WD33C93
 * chip deciding that the device isn't responding.
 */
#define TIMEOUT_TIME 10
/*
 * Define this if you want to have verbose explanation of SCSI
 * status/messages.
 */
#undef CONFIG_ACORNSCSI_CONSTANTS
/*
 * Define this if you want to use the on board DMAC [don't remove this option]
 * If not set, then use PIO mode (not currently supported).
 */
#define USE_DMAC

/*
 * ====================================================================================
 */

#ifdef DEBUG_TARGET
#define DBG(cmd,xxx...) \
  if (cmd->device->id == DEBUG_TARGET) { \
    xxx; \
  }
#else
#define DBG(cmd,xxx...) xxx
#endif

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/signal.h>
#include <linux/errno.h>
#include <linux/proc_fs.h>
#include <linux/ioport.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/stringify.h>
#include <linux/io.h>

#include <asm/system.h>
#include <asm/ecard.h>

#include "../scsi.h"
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport_spi.h>
#include "acornscsi.h"
#include "msgqueue.h"
#include "scsi.h"

#include <scsi/scsicam.h>

#define VER_MAJOR 2
#define VER_MINOR 0
#define VER_PATCH 6

#ifndef ABORT_TAG
#define ABORT_TAG 0xd
#else
#error "Yippee!  ABORT TAG is now defined!  Remove this error!"
#endif

#ifdef CONFIG_SCSI_ACORNSCSI_LINK
#error SCSI2 LINKed commands not supported (yet)!
#endif

#ifdef USE_DMAC
/*
 * DMAC setup parameters
 */ 
#define INIT_DEVCON0	(DEVCON0_RQL|DEVCON0_EXW|DEVCON0_CMP)
#define INIT_DEVCON1	(DEVCON1_BHLD)
#define DMAC_READ	(MODECON_READ)
#define DMAC_WRITE	(MODECON_WRITE)
#define INIT_SBICDMA	(CTRL_DMABURST)

#define scsi_xferred	have_data_in

/*
 * Size of on-board DMA buffer
 */
#define DMAC_BUFFER_SIZE	65536
#endif

#define STATUS_BUFFER_TO_PRINT	24

unsigned int sdtr_period = SDTR_PERIOD;
unsigned int sdtr_size   = SDTR_SIZE;

static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
			   unsigned int result);
static int acornscsi_reconnect_finish(AS_Host *host);
static void acornscsi_dma_cleanup(AS_Host *host);
static void acornscsi_abortcmd(AS_Host *host, unsigned char tag);

/* ====================================================================================
 * Miscellaneous
 */

/* Offsets from MEMC base */
#define SBIC_REGIDX	0x2000
#define SBIC_REGVAL	0x2004
#define DMAC_OFFSET	0x3000

/* Offsets from FAST IOC base */
#define INT_REG		0x2000
#define PAGE_REG	0x3000

static inline void sbic_arm_write(AS_Host *host, unsigned int reg, unsigned int value)
{
    writeb(reg, host->base + SBIC_REGIDX);
    writeb(value, host->base + SBIC_REGVAL);
}

static inline int sbic_arm_read(AS_Host *host, unsigned int reg)
{
    if(reg == SBIC_ASR)
	   return readl(host->base + SBIC_REGIDX) & 255;
    writeb(reg, host->base + SBIC_REGIDX);
    return readl(host->base + SBIC_REGVAL) & 255;
}

#define sbic_arm_writenext(host, val)	writeb((val), (host)->base + SBIC_REGVAL)
#define sbic_arm_readnext(host) 	readb((host)->base + SBIC_REGVAL)

#ifdef USE_DMAC
#define dmac_read(host,reg) \
	readb((host)->base + DMAC_OFFSET + ((reg) << 2))

#define dmac_write(host,reg,value) \
	({ writeb((value), (host)->base + DMAC_OFFSET + ((reg) << 2)); })

#define dmac_clearintr(host) 	writeb(0, (host)->fast + INT_REG)

static inline unsigned int dmac_address(AS_Host *host)
{
    return dmac_read(host, DMAC_TXADRHI) << 16 |
	   dmac_read(host, DMAC_TXADRMD) << 8 |
	   dmac_read(host, DMAC_TXADRLO);
}

static
void acornscsi_dumpdma(AS_Host *host, char *where)
{
	unsigned int mode, addr, len;

	mode = dmac_read(host, DMAC_MODECON);
	addr = dmac_address(host);
	len  = dmac_read(host, DMAC_TXCNTHI) << 8 |
	       dmac_read(host, DMAC_TXCNTLO);

	printk("scsi%d: %s: DMAC %02x @%06x+%04x msk %02x, ",
		host->host->host_no, where,
		mode, addr, (len + 1) & 0xffff,
		dmac_read(host, DMAC_MASKREG));

	printk("DMA @%06x, ", host->dma.start_addr);
	printk("BH @%p +%04x, ", host->scsi.SCp.ptr,
		host->scsi.SCp.this_residual);
	printk("DT @+%04x ST @+%04x", host->dma.transferred,
		host->scsi.SCp.scsi_xferred);
	printk("\n");
}
#endif

static
unsigned long acornscsi_sbic_xfcount(AS_Host *host)
{
    unsigned long length;

    length = sbic_arm_read(host, SBIC_TRANSCNTH) << 16;
    length |= sbic_arm_readnext(host) << 8;
    length |= sbic_arm_readnext(host);

    return length;
}

static int
acornscsi_sbic_wait(AS_Host *host, int stat_mask, int stat, int timeout, char *msg)
{
	int asr;

	do {
		asr = sbic_arm_read(host, SBIC_ASR);

		if ((asr & stat_mask) == stat)
			return 0;

		udelay(1);
	} while (--timeout);

	printk("scsi%d: timeout while %s\n", host->host->host_no, msg);

	return -1;
}

static
int acornscsi_sbic_issuecmd(AS_Host *host, int command)
{
    if (acornscsi_sbic_wait(host, ASR_CIP, 0, 1000, "issuing command"))
	return -1;

    sbic_arm_write(host, SBIC_CMND, command);

    return 0;
}

static void
acornscsi_csdelay(unsigned int cs)
{
    unsigned long target_jiffies, flags;

    target_jiffies = jiffies + 1 + cs * HZ / 100;

    local_save_flags(flags);
    local_irq_enable();

    while (time_before(jiffies, target_jiffies)) barrier();

    local_irq_restore(flags);
}

static
void acornscsi_resetcard(AS_Host *host)
{
    unsigned int i, timeout;

    /* assert reset line */
    host->card.page_reg = 0x80;
    writeb(host->card.page_reg, host->fast + PAGE_REG);

    /* wait 3 cs.  SCSI standard says 25ms. */
    acornscsi_csdelay(3);

    host->card.page_reg = 0;
    writeb(host->card.page_reg, host->fast + PAGE_REG);

    /*
     * Should get a reset from the card
     */
    timeout = 1000;
    do {
	if (readb(host->fast + INT_REG) & 8)
	    break;
	udelay(1);
    } while (--timeout);

    if (timeout == 0)
	printk("scsi%d: timeout while resetting card\n",
		host->host->host_no);

    sbic_arm_read(host, SBIC_ASR);
    sbic_arm_read(host, SBIC_SSR);

    /* setup sbic - WD33C93A */
    sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
    sbic_arm_write(host, SBIC_CMND, CMND_RESET);

    /*
     * Command should cause a reset interrupt
     */
    timeout = 1000;
    do {
	if (readb(host->fast + INT_REG) & 8)
	    break;
	udelay(1);
    } while (--timeout);

    if (timeout == 0)
	printk("scsi%d: timeout while resetting card\n",
		host->host->host_no);

    sbic_arm_read(host, SBIC_ASR);
    if (sbic_arm_read(host, SBIC_SSR) != 0x01)
	printk(KERN_CRIT "scsi%d: WD33C93A didn't give enhanced reset interrupt\n",
		host->host->host_no);

    sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
    sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
    sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
    sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);

    host->card.page_reg = 0x40;
    writeb(host->card.page_reg, host->fast + PAGE_REG);

    /* setup dmac - uPC71071 */
    dmac_write(host, DMAC_INIT, 0);
#ifdef USE_DMAC
    dmac_write(host, DMAC_INIT, INIT_8BIT);
    dmac_write(host, DMAC_CHANNEL, CHANNEL_0);
    dmac_write(host, DMAC_DEVCON0, INIT_DEVCON0);
    dmac_write(host, DMAC_DEVCON1, INIT_DEVCON1);
#endif

    host->SCpnt = NULL;
    host->scsi.phase = PHASE_IDLE;
    host->scsi.disconnectable = 0;

    memset(host->busyluns, 0, sizeof(host->busyluns));

    for (i = 0; i < 8; i++) {
	host->device[i].sync_state = SYNC_NEGOCIATE;
	host->device[i].disconnect_ok = 1;
    }

    /* wait 25 cs.  SCSI standard says 250ms. */
    acornscsi_csdelay(25);
}

/*=============================================================================================
 * Utility routines (eg. debug)
 */
#ifdef CONFIG_ACORNSCSI_CONSTANTS
static char *acornscsi_interrupttype[] = {
  "rst",  "suc",  "p/a",  "3",
  "term", "5",	  "6",	  "7",
  "serv", "9",	  "a",	  "b",
  "c",	  "d",	  "e",	  "f"
};

static signed char acornscsi_map[] = {
  0,  1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1,  2, -1, -1,  -1, -1,  3, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 12, 13, 14, -1,  -1, -1, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 15, 16, 17, 18,  19, -1, -1, 20,   4,	5,  6,	7,   8,  9, 10, 11,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 21, 22, -1, -1,  -1, 23, -1, -1,   4,	5,  6,	7,   8,  9, 10, 11,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,
 -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1,  -1, -1, -1, -1
};      

static char *acornscsi_interruptcode[] = {
    /* 0 */
    "reset - normal mode",	/* 00 */
    "reset - advanced mode",	/* 01 */

    /* 2 */
    "sel",			/* 11 */
    "sel+xfer", 		/* 16 */
    "data-out", 		/* 18 */
    "data-in",			/* 19 */
    "cmd",			/* 1A */
    "stat",			/* 1B */
    "??-out",			/* 1C */
    "??-in",			/* 1D */
    "msg-out",			/* 1E */
    "msg-in",			/* 1F */

    /* 12 */
    "/ACK asserted",		/* 20 */
    "save-data-ptr",		/* 21 */
    "{re}sel",			/* 22 */

    /* 15 */
    "inv cmd",			/* 40 */
    "unexpected disconnect",	/* 41 */
    "sel timeout",		/* 42 */
    "P err",			/* 43 */
    "P err+ATN",		/* 44 */
    "bad status byte",		/* 47 */

    /* 21 */
    "resel, no id",		/* 80 */
    "resel",			/* 81 */
    "discon",			/* 85 */
};

static
void print_scsi_status(unsigned int ssr)
{
    if (acornscsi_map[ssr] != -1)
	printk("%s:%s",
		acornscsi_interrupttype[(ssr >> 4)],
		acornscsi_interruptcode[acornscsi_map[ssr]]);
    else
	printk("%X:%X", ssr >> 4, ssr & 0x0f);    
}    
#endif

static
void print_sbic_status(int asr, int ssr, int cmdphase)
{
#ifdef CONFIG_ACORNSCSI_CONSTANTS
    printk("sbic: %c%c%c%c%c%c ",
	    asr & ASR_INT ? 'I' : 'i',
	    asr & ASR_LCI ? 'L' : 'l',
	    asr & ASR_BSY ? 'B' : 'b',
	    asr & ASR_CIP ? 'C' : 'c',
	    asr & ASR_PE  ? 'P' : 'p',
	    asr & ASR_DBR ? 'D' : 'd');
    printk("scsi: ");
    print_scsi_status(ssr);
    printk(" ph %02X\n", cmdphase);
#else
    printk("sbic: %02X scsi: %X:%X ph: %02X\n",
	    asr, (ssr & 0xf0)>>4, ssr & 0x0f, cmdphase);
#endif
}

static void
acornscsi_dumplogline(AS_Host *host, int target, int line)
{
	unsigned long prev;
	signed int ptr;

	ptr = host->status_ptr[target] - STATUS_BUFFER_TO_PRINT;
	if (ptr < 0)
		ptr += STATUS_BUFFER_SIZE;

	printk("%c: %3s:", target == 8 ? 'H' : '0' + target,
		line == 0 ? "ph" : line == 1 ? "ssr" : "int");

	prev = host->status[target][ptr].when;

	for (; ptr != host->status_ptr[target]; ptr = (ptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
		unsigned long time_diff;

		if (!host->status[target][ptr].when)
			continue;

		switch (line) {
		case 0:
			printk("%c%02X", host->status[target][ptr].irq ? '-' : ' ',
					 host->status[target][ptr].ph);
			break;

		case 1:
			printk(" %02X", host->status[target][ptr].ssr);
			break;

		case 2:
			time_diff = host->status[target][ptr].when - prev;
			prev = host->status[target][ptr].when;
			if (time_diff == 0)
				printk("==^");
			else if (time_diff >= 100)
				printk("   ");
			else
				printk(" %02ld", time_diff);
			break;
		}
	}

	printk("\n");
}

static
void acornscsi_dumplog(AS_Host *host, int target)
{
    do {
	acornscsi_dumplogline(host, target, 0);
	acornscsi_dumplogline(host, target, 1);
	acornscsi_dumplogline(host, target, 2);

	if (target == 8)
	    break;

	target = 8;
    } while (1);
}

static
char acornscsi_target(AS_Host *host)
{
	if (host->SCpnt)
		return '0' + host->SCpnt->device->id;
	return 'H';
}

/*
 * Prototype: cmdtype_t acornscsi_cmdtype(int command)
 * Purpose  : differentiate READ from WRITE from other commands
 * Params   : command - command to interpret
 * Returns  : CMD_READ	- command reads data,
 *	      CMD_WRITE - command writes data,
 *	      CMD_MISC	- everything else
 */
static inline
cmdtype_t acornscsi_cmdtype(int command)
{
    switch (command) {
    case WRITE_6:  case WRITE_10:  case WRITE_12:
	return CMD_WRITE;
    case READ_6:   case READ_10:   case READ_12:
	return CMD_READ;
    default:
	return CMD_MISC;
    }
}

/*
 * Prototype: int acornscsi_datadirection(int command)
 * Purpose  : differentiate between commands that have a DATA IN phase
 *	      and a DATA OUT phase
 * Params   : command - command to interpret
 * Returns  : DATADIR_OUT - data out phase expected
 *	      DATADIR_IN  - data in phase expected
 */
static
datadir_t acornscsi_datadirection(int command)
{
    switch (command) {
    case CHANGE_DEFINITION:	case COMPARE:		case COPY:
    case COPY_VERIFY:		case LOG_SELECT:	case MODE_SELECT:
    case MODE_SELECT_10:	case SEND_DIAGNOSTIC:	case WRITE_BUFFER:
    case FORMAT_UNIT:		case REASSIGN_BLOCKS:	case RESERVE:
    case SEARCH_EQUAL:		case SEARCH_HIGH:	case SEARCH_LOW:
    case WRITE_6:		case WRITE_10:		case WRITE_VERIFY:
    case UPDATE_BLOCK:		case WRITE_LONG:	case WRITE_SAME:
    case SEARCH_HIGH_12:	case SEARCH_EQUAL_12:	case SEARCH_LOW_12:
    case WRITE_12:		case WRITE_VERIFY_12:	case SET_WINDOW:
    case MEDIUM_SCAN:		case SEND_VOLUME_TAG:	case 0xea:
	return DATADIR_OUT;
    default:
	return DATADIR_IN;
    }
}

/*
 * Purpose  : provide values for synchronous transfers with 33C93.
 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
 *	Modified by Russell King for 8MHz WD33C93A
 */
static struct sync_xfer_tbl {
    unsigned int period_ns;
    unsigned char reg_value;
} sync_xfer_table[] = {
    {	1, 0x20 },    { 249, 0x20 },	{ 374, 0x30 },
    { 499, 0x40 },    { 624, 0x50 },	{ 749, 0x60 },
    { 874, 0x70 },    { 999, 0x00 },	{   0,	  0 }
};

/*
 * Prototype: int acornscsi_getperiod(unsigned char syncxfer)
 * Purpose  : period for the synchronous transfer setting
 * Params   : syncxfer SYNCXFER register value
 * Returns  : period in ns.
 */
static
int acornscsi_getperiod(unsigned char syncxfer)
{
    int i;

    syncxfer &= 0xf0;
    if (syncxfer == 0x10)
	syncxfer = 0;

    for (i = 1; sync_xfer_table[i].period_ns; i++)
	if (syncxfer == sync_xfer_table[i].reg_value)
	    return sync_xfer_table[i].period_ns;
    return 0;
}

/*
 * Prototype: int round_period(unsigned int period)
 * Purpose  : return index into above table for a required REQ period
 * Params   : period - time (ns) for REQ
 * Returns  : table index
 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
 */
static inline
int round_period(unsigned int period)
{
    int i;

    for (i = 1; sync_xfer_table[i].period_ns; i++) {
	if ((period <= sync_xfer_table[i].period_ns) &&
	    (period > sync_xfer_table[i - 1].period_ns))
	    return i;
    }
    return 7;
}

/*
 * Prototype: unsigned char calc_sync_xfer(unsigned int period, unsigned int offset)
 * Purpose  : calculate value for 33c93s SYNC register
 * Params   : period - time (ns) for REQ
 *	      offset - offset in bytes between REQ/ACK
 * Returns  : value for SYNC register
 * Copyright: Copyright (c) 1996 John Shifflett, GeoLog Consulting
 */
static
unsigned char calc_sync_xfer(unsigned int period, unsigned int offset)
{
    return sync_xfer_table[round_period(period)].reg_value |
		((offset < SDTR_SIZE) ? offset : SDTR_SIZE);
}

/* ====================================================================================
 * Command functions
 */
/*
 * Function: acornscsi_kick(AS_Host *host)
 * Purpose : kick next command to interface
 * Params  : host - host to send command to
 * Returns : INTR_IDLE if idle, otherwise INTR_PROCESSING
 * Notes   : interrupts are always disabled!
 */
static
intr_ret_t acornscsi_kick(AS_Host *host)
{
    int from_queue = 0;
    struct scsi_cmnd *SCpnt;

    /* first check to see if a command is waiting to be executed */
    SCpnt = host->origSCpnt;
    host->origSCpnt = NULL;

    /* retrieve next command */
    if (!SCpnt) {
	SCpnt = queue_remove_exclude(&host->queues.issue, host->busyluns);
	if (!SCpnt)
	    return INTR_IDLE;

	from_queue = 1;
    }

    if (host->scsi.disconnectable && host->SCpnt) {
	queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
	host->scsi.disconnectable = 0;
#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
	DBG(host->SCpnt, printk("scsi%d.%c: moved command to disconnected queue\n",
		host->host->host_no, acornscsi_target(host)));
#endif
	host->SCpnt = NULL;
    }

    /*
     * If we have an interrupt pending, then we may have been reselected.
     * In this case, we don't want to write to the registers
     */
    if (!(sbic_arm_read(host, SBIC_ASR) & (ASR_INT|ASR_BSY|ASR_CIP))) {
	sbic_arm_write(host, SBIC_DESTID, SCpnt->device->id);
	sbic_arm_write(host, SBIC_CMND, CMND_SELWITHATN);
    }

    /*
     * claim host busy - all of these must happen atomically wrt
     * our interrupt routine.  Failure means command loss.
     */
    host->scsi.phase = PHASE_CONNECTING;
    host->SCpnt = SCpnt;
    host->scsi.SCp = SCpnt->SCp;
    host->dma.xfer_setup = 0;
    host->dma.xfer_required = 0;
    host->dma.xfer_done = 0;

#if (DEBUG & (DEBUG_ABORT|DEBUG_CONNECT))
    DBG(SCpnt,printk("scsi%d.%c: starting cmd %02X\n",
	    host->host->host_no, '0' + SCpnt->device->id,
	    SCpnt->cmnd[0]));
#endif

    if (from_queue) {
#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
	/*
	 * tagged queueing - allocate a new tag to this command
	 */
	if (SCpnt->device->simple_tags) {
	    SCpnt->device->current_tag += 1;
	    if (SCpnt->device->current_tag == 0)
		SCpnt->device->current_tag = 1;
	    SCpnt->tag = SCpnt->device->current_tag;
	} else
#endif
	    set_bit(SCpnt->device->id * 8 + SCpnt->device->lun, host->busyluns);

	host->stats.removes += 1;

	switch (acornscsi_cmdtype(SCpnt->cmnd[0])) {
	case CMD_WRITE:
	    host->stats.writes += 1;
	    break;
	case CMD_READ:
	    host->stats.reads += 1;
	    break;
	case CMD_MISC:
	    host->stats.miscs += 1;
	    break;
	}
    }

    return INTR_PROCESSING;
}    

/*
 * Function: void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp, unsigned int result)
 * Purpose : complete processing for command
 * Params  : host   - interface that completed
 *	     result - driver byte of result
 */
static void acornscsi_done(AS_Host *host, struct scsi_cmnd **SCpntp,
			   unsigned int result)
{
	struct scsi_cmnd *SCpnt = *SCpntp;

    /* clean up */
    sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);

    host->stats.fins += 1;

    if (SCpnt) {
	*SCpntp = NULL;

	acornscsi_dma_cleanup(host);

	SCpnt->result = result << 16 | host->scsi.SCp.Message << 8 | host->scsi.SCp.Status;

	/*
	 * In theory, this should not happen.  In practice, it seems to.
	 * Only trigger an error if the device attempts to report all happy
	 * but with untransferred buffers...  If we don't do something, then
	 * data loss will occur.  Should we check SCpnt->underflow here?
	 * It doesn't appear to be set to something meaningful by the higher
	 * levels all the time.
	 */
	if (result == DID_OK) {
		int xfer_warn = 0;

		if (SCpnt->underflow == 0) {
			if (host->scsi.SCp.ptr &&
			    acornscsi_cmdtype(SCpnt->cmnd[0]) != CMD_MISC)
				xfer_warn = 1;
		} else {
			if (host->scsi.SCp.scsi_xferred < SCpnt->underflow ||
			    host->scsi.SCp.scsi_xferred != host->dma.transferred)
				xfer_warn = 1;
		}

		/* ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.6)
		 *  Targets which break data transfers into multiple
		 *  connections shall end each successful connection
		 *  (except possibly the last) with a SAVE DATA
		 *  POINTER - DISCONNECT message sequence.
		 *
		 * This makes it difficult to ensure that a transfer has
		 * completed.  If we reach the end of a transfer during
		 * the command, then we can only have finished the transfer.
		 * therefore, if we seem to have some data remaining, this
		 * is not a problem.
		 */
		if (host->dma.xfer_done)
			xfer_warn = 0;

		if (xfer_warn) {
		    switch (status_byte(SCpnt->result)) {
		    case CHECK_CONDITION:
		    case COMMAND_TERMINATED:
		    case BUSY:
		    case QUEUE_FULL:
		    case RESERVATION_CONFLICT:
			break;

		    default:
			printk(KERN_ERR "scsi%d.H: incomplete data transfer detected: result=%08X command=",
				host->host->host_no, SCpnt->result);
			__scsi_print_command(SCpnt->cmnd);
			acornscsi_dumpdma(host, "done");
		 	acornscsi_dumplog(host, SCpnt->device->id);
			SCpnt->result &= 0xffff;
			SCpnt->result |= DID_ERROR << 16;
		    }
		}
	}

	if (!SCpnt->scsi_done)
	    panic("scsi%d.H: null scsi_done function in acornscsi_done", host->host->host_no);

	clear_bit(SCpnt->device->id * 8 + SCpnt->device->lun, host->busyluns);

	SCpnt->scsi_done(SCpnt);
    } else
	printk("scsi%d: null command in acornscsi_done", host->host->host_no);

    host->scsi.phase = PHASE_IDLE;
}

/* ====================================================================================
 * DMA routines
 */
/*
 * Purpose  : update SCSI Data Pointer
 * Notes    : this will only be one SG entry or less
 */
static
void acornscsi_data_updateptr(AS_Host *host, struct scsi_pointer *SCp, unsigned int length)
{
    SCp->ptr += length;
    SCp->this_residual -= length;

    if (SCp->this_residual == 0 && next_SCp(SCp) == 0)
	host->dma.xfer_done = 1;
}

/*
 * Prototype: void acornscsi_data_read(AS_Host *host, char *ptr,
 *				unsigned int start_addr, unsigned int length)
 * Purpose  : read data from DMA RAM
 * Params   : host - host to transfer from
 *	      ptr  - DRAM address
 *	      start_addr - host mem address
 *	      length - number of bytes to transfer
 * Notes    : this will only be one SG entry or less
 */
static
void acornscsi_data_read(AS_Host *host, char *ptr,
				 unsigned int start_addr, unsigned int length)
{
    extern void __acornscsi_in(void __iomem *, char *buf, int len);
    unsigned int page, offset, len = length;

    page = (start_addr >> 12);
    offset = start_addr & ((1 << 12) - 1);

    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);

    while (len > 0) {
	unsigned int this_len;

	if (len + offset > (1 << 12))
	    this_len = (1 << 12) - offset;
	else
	    this_len = len;

	__acornscsi_in(host->base + (offset << 1), ptr, this_len);

	offset += this_len;
	ptr += this_len;
	len -= this_len;

	if (offset == (1 << 12)) {
	    offset = 0;
	    page ++;
	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
	}
    }
    writeb(host->card.page_reg, host->fast + PAGE_REG);
}

/*
 * Prototype: void acornscsi_data_write(AS_Host *host, char *ptr,
 *				unsigned int start_addr, unsigned int length)
 * Purpose  : write data to DMA RAM
 * Params   : host - host to transfer from
 *	      ptr  - DRAM address
 *	      start_addr - host mem address
 *	      length - number of bytes to transfer
 * Notes    : this will only be one SG entry or less
 */
static
void acornscsi_data_write(AS_Host *host, char *ptr,
				 unsigned int start_addr, unsigned int length)
{
    extern void __acornscsi_out(void __iomem *, char *buf, int len);
    unsigned int page, offset, len = length;

    page = (start_addr >> 12);
    offset = start_addr & ((1 << 12) - 1);

    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);

    while (len > 0) {
	unsigned int this_len;

	if (len + offset > (1 << 12))
	    this_len = (1 << 12) - offset;
	else
	    this_len = len;

	__acornscsi_out(host->base + (offset << 1), ptr, this_len);

	offset += this_len;
	ptr += this_len;
	len -= this_len;

	if (offset == (1 << 12)) {
	    offset = 0;
	    page ++;
	    writeb((page & 0x3f) | host->card.page_reg, host->fast + PAGE_REG);
	}
    }
    writeb(host->card.page_reg, host->fast + PAGE_REG);
}

/* =========================================================================================
 * On-board DMA routines
 */
#ifdef USE_DMAC
/*
 * Prototype: void acornscsi_dmastop(AS_Host *host)
 * Purpose  : stop all DMA
 * Params   : host - host on which to stop DMA
 * Notes    : This is called when leaving DATA IN/OUT phase,
 *	      or when interface is RESET
 */
static inline
void acornscsi_dma_stop(AS_Host *host)
{
    dmac_write(host, DMAC_MASKREG, MASK_ON);
    dmac_clearintr(host);

#if (DEBUG & DEBUG_DMA)
    DBG(host->SCpnt, acornscsi_dumpdma(host, "stop"));
#endif
}

/*
 * Function: void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
 * Purpose : setup DMA controller for data transfer
 * Params  : host - host to setup
 *	     direction - data transfer direction
 * Notes   : This is called when entering DATA I/O phase, not
 *	     while we're in a DATA I/O phase
 */
static
void acornscsi_dma_setup(AS_Host *host, dmadir_t direction)
{
    unsigned int address, length, mode;

    host->dma.direction = direction;

    dmac_write(host, DMAC_MASKREG, MASK_ON);

    if (direction == DMA_OUT) {
#if (DEBUG & DEBUG_NO_WRITE)
	if (NO_WRITE & (1 << host->SCpnt->device->id)) {
	    printk(KERN_CRIT "scsi%d.%c: I can't handle DMA_OUT!\n",
		    host->host->host_no, acornscsi_target(host));
	    return;
	}
#endif
	mode = DMAC_WRITE;
    } else
	mode = DMAC_READ;

    /*
     * Allocate some buffer space, limited to half the buffer size
     */
    length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
    if (length) {
	host->dma.start_addr = address = host->dma.free_addr;
	host->dma.free_addr = (host->dma.free_addr + length) &
				(DMAC_BUFFER_SIZE - 1);

	/*
	 * Transfer data to DMA memory
	 */
	if (direction == DMA_OUT)
	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
				length);

	length -= 1;
	dmac_write(host, DMAC_TXCNTLO, length);
	dmac_write(host, DMAC_TXCNTHI, length >> 8);
	dmac_write(host, DMAC_TXADRLO, address);
	dmac_write(host, DMAC_TXADRMD, address >> 8);
	dmac_write(host, DMAC_TXADRHI, 0);
	dmac_write(host, DMAC_MODECON, mode);
	dmac_write(host, DMAC_MASKREG, MASK_OFF);

#if (DEBUG & DEBUG_DMA)
	DBG(host->SCpnt, acornscsi_dumpdma(host, "strt"));
#endif
	host->dma.xfer_setup = 1;
    }
}

/*
 * Function: void acornscsi_dma_cleanup(AS_Host *host)
 * Purpose : ensure that all DMA transfers are up-to-date & host->scsi.SCp is correct
 * Params  : host - host to finish
 * Notes   : This is called when a command is:
 *		terminating, RESTORE_POINTERS, SAVE_POINTERS, DISCONECT
 *	   : This must not return until all transfers are completed.
 */
static
void acornscsi_dma_cleanup(AS_Host *host)
{
    dmac_write(host, DMAC_MASKREG, MASK_ON);
    dmac_clearintr(host);

    /*
     * Check for a pending transfer
     */
    if (host->dma.xfer_required) {
	host->dma.xfer_required = 0;
	if (host->dma.direction == DMA_IN)
	    acornscsi_data_read(host, host->dma.xfer_ptr,
				 host->dma.xfer_start, host->dma.xfer_length);
    }

    /*
     * Has a transfer been setup?
     */
    if (host->dma.xfer_setup) {
	unsigned int transferred;

	host->dma.xfer_setup = 0;

#if (DEBUG & DEBUG_DMA)
	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupi"));
#endif

	/*
	 * Calculate number of bytes transferred from DMA.
	 */
	transferred = dmac_address(host) - host->dma.start_addr;
	host->dma.transferred += transferred;

	if (host->dma.direction == DMA_IN)
	    acornscsi_data_read(host, host->scsi.SCp.ptr,
				 host->dma.start_addr, transferred);

	/*
	 * Update SCSI pointers
	 */
	acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);
#if (DEBUG & DEBUG_DMA)
	DBG(host->SCpnt, acornscsi_dumpdma(host, "cupo"));
#endif
    }
}

/*
 * Function: void acornscsi_dmacintr(AS_Host *host)
 * Purpose : handle interrupts from DMAC device
 * Params  : host - host to process
 * Notes   : If reading, we schedule the read to main memory &
 *	     allow the transfer to continue.
 *	   : If writing, we fill the onboard DMA memory from main
 *	     memory.
 *	   : Called whenever DMAC finished it's current transfer.
 */
static
void acornscsi_dma_intr(AS_Host *host)
{
    unsigned int address, length, transferred;

#if (DEBUG & DEBUG_DMA)
    DBG(host->SCpnt, acornscsi_dumpdma(host, "inti"));
#endif

    dmac_write(host, DMAC_MASKREG, MASK_ON);
    dmac_clearintr(host);

    /*
     * Calculate amount transferred via DMA
     */
    transferred = dmac_address(host) - host->dma.start_addr;
    host->dma.transferred += transferred;

    /*
     * Schedule DMA transfer off board
     */
    if (host->dma.direction == DMA_IN) {
	host->dma.xfer_start = host->dma.start_addr;
	host->dma.xfer_length = transferred;
	host->dma.xfer_ptr = host->scsi.SCp.ptr;
	host->dma.xfer_required = 1;
    }

    acornscsi_data_updateptr(host, &host->scsi.SCp, transferred);

    /*
     * Allocate some buffer space, limited to half the on-board RAM size
     */
    length = min_t(unsigned int, host->scsi.SCp.this_residual, DMAC_BUFFER_SIZE / 2);
    if (length) {
	host->dma.start_addr = address = host->dma.free_addr;
	host->dma.free_addr = (host->dma.free_addr + length) &
				(DMAC_BUFFER_SIZE - 1);

	/*
	 * Transfer data to DMA memory
	 */
	if (host->dma.direction == DMA_OUT)
	    acornscsi_data_write(host, host->scsi.SCp.ptr, host->dma.start_addr,
				length);

	length -= 1;
	dmac_write(host, DMAC_TXCNTLO, length);
	dmac_write(host, DMAC_TXCNTHI, length >> 8);
	dmac_write(host, DMAC_TXADRLO, address);
	dmac_write(host, DMAC_TXADRMD, address >> 8);
	dmac_write(host, DMAC_TXADRHI, 0);
	dmac_write(host, DMAC_MASKREG, MASK_OFF);

#if (DEBUG & DEBUG_DMA)
	DBG(host->SCpnt, acornscsi_dumpdma(host, "into"));
#endif
    } else {
	host->dma.xfer_setup = 0;
#if 0
	/*
	 * If the interface still wants more, then this is an error.
	 * We give it another byte, but we also attempt to raise an
	 * attention condition.  We continue giving one byte until
	 * the device recognises the attention.
	 */
	if (dmac_read(host, DMAC_STATUS) & STATUS_RQ0) {
	    acornscsi_abortcmd(host, host->SCpnt->tag);

	    dmac_write(host, DMAC_TXCNTLO, 0);
	    dmac_write(host, DMAC_TXCNTHI, 0);
	    dmac_write(host, DMAC_TXADRLO, 0);
	    dmac_write(host, DMAC_TXADRMD, 0);
	    dmac_write(host, DMAC_TXADRHI, 0);
	    dmac_write(host, DMAC_MASKREG, MASK_OFF);
	}
#endif
    }
}

/*
 * Function: void acornscsi_dma_xfer(AS_Host *host)
 * Purpose : transfer data between AcornSCSI and memory
 * Params  : host - host to process
 */
static
void acornscsi_dma_xfer(AS_Host *host)
{
    host->dma.xfer_required = 0;

    if (host->dma.direction == DMA_IN)
	acornscsi_data_read(host, host->dma.xfer_ptr,
				host->dma.xfer_start, host->dma.xfer_length);
}

/*
 * Function: void acornscsi_dma_adjust(AS_Host *host)
 * Purpose : adjust DMA pointers & count for bytes transferred to
 *	     SBIC but not SCSI bus.
 * Params  : host - host to adjust DMA count for
 */
static
void acornscsi_dma_adjust(AS_Host *host)
{
    if (host->dma.xfer_setup) {
	signed long transferred;
#if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
	DBG(host->SCpnt, acornscsi_dumpdma(host, "adji"));
#endif
	/*
	 * Calculate correct DMA address - DMA is ahead of SCSI bus while
	 * writing.
	 *  host->scsi.SCp.scsi_xferred is the number of bytes
	 *  actually transferred to/from the SCSI bus.
	 *  host->dma.transferred is the number of bytes transferred
	 *  over DMA since host->dma.start_addr was last set.
	 *
	 * real_dma_addr = host->dma.start_addr + host->scsi.SCp.scsi_xferred
	 *		   - host->dma.transferred
	 */
	transferred = host->scsi.SCp.scsi_xferred - host->dma.transferred;
	if (transferred < 0)
	    printk("scsi%d.%c: Ack! DMA write correction %ld < 0!\n",
		    host->host->host_no, acornscsi_target(host), transferred);
	else if (transferred == 0)
	    host->dma.xfer_setup = 0;
	else {
	    transferred += host->dma.start_addr;
	    dmac_write(host, DMAC_TXADRLO, transferred);
	    dmac_write(host, DMAC_TXADRMD, transferred >> 8);
	    dmac_write(host, DMAC_TXADRHI, transferred >> 16);
#if (DEBUG & (DEBUG_DMA|DEBUG_WRITE))
	    DBG(host->SCpnt, acornscsi_dumpdma(host, "adjo"));
#endif
	}
    }
}
#endif

/* =========================================================================================
 * Data I/O
 */
static int
acornscsi_write_pio(AS_Host *host, char *bytes, int *ptr, int len, unsigned int max_timeout)
{
	unsigned int asr, timeout = max_timeout;
	int my_ptr = *ptr;

	while (my_ptr < len) {
		asr = sbic_arm_read(host, SBIC_ASR);

		if (asr & ASR_DBR) {
			timeout = max_timeout;

			sbic_arm_write(host, SBIC_DATA, bytes[my_ptr++]);
		} else if (asr & ASR_INT)
			break;
		else if (--timeout == 0)
			break;
		udelay(1);
	}

	*ptr = my_ptr;

	return (timeout == 0) ? -1 : 0;
}

/*
 * Function: void acornscsi_sendcommand(AS_Host *host)
 * Purpose : send a command to a target
 * Params  : host - host which is connected to target
 */
static void
acornscsi_sendcommand(AS_Host *host)
{
	struct scsi_cmnd *SCpnt = host->SCpnt;

    sbic_arm_write(host, SBIC_TRANSCNTH, 0);
    sbic_arm_writenext(host, 0);
    sbic_arm_writenext(host, SCpnt->cmd_len - host->scsi.SCp.sent_command);

    acornscsi_sbic_issuecmd(host, CMND_XFERINFO);

    if (acornscsi_write_pio(host, SCpnt->cmnd,
	(int *)&host->scsi.SCp.sent_command, SCpnt->cmd_len, 1000000))
	printk("scsi%d: timeout while sending command\n", host->host->host_no);

    host->scsi.phase = PHASE_COMMAND;
}

static
void acornscsi_sendmessage(AS_Host *host)
{
    unsigned int message_length = msgqueue_msglength(&host->scsi.msgs);
    unsigned int msgnr;
    struct message *msg;

#if (DEBUG & DEBUG_MESSAGES)
    printk("scsi%d.%c: sending message ",
	    host->host->host_no, acornscsi_target(host));
#endif

    switch (message_length) {
    case 0:
	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);

	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 1");

	sbic_arm_write(host, SBIC_DATA, NOP);

	host->scsi.last_message = NOP;
#if (DEBUG & DEBUG_MESSAGES)
	printk("NOP");
#endif
	break;

    case 1:
	acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);
	msg = msgqueue_getmsg(&host->scsi.msgs, 0);

	acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "sending message 2");

	sbic_arm_write(host, SBIC_DATA, msg->msg[0]);

	host->scsi.last_message = msg->msg[0];
#if (DEBUG & DEBUG_MESSAGES)
	spi_print_msg(msg->msg);
#endif
	break;

    default:
	/*
	 * ANSI standard says: (SCSI-2 Rev 10c Sect 5.6.14)
	 * 'When a target sends this (MESSAGE_REJECT) message, it
	 *  shall change to MESSAGE IN phase and send this message
	 *  prior to requesting additional message bytes from the
	 *  initiator.  This provides an interlock so that the
	 *  initiator can determine which message byte is rejected.
	 */
	sbic_arm_write(host, SBIC_TRANSCNTH, 0);
	sbic_arm_writenext(host, 0);
	sbic_arm_writenext(host, message_length);
	acornscsi_sbic_issuecmd(host, CMND_XFERINFO);

	msgnr = 0;
	while ((msg = msgqueue_getmsg(&host->scsi.msgs, msgnr++)) != NULL) {
	    unsigned int i;
#if (DEBUG & DEBUG_MESSAGES)
	    spi_print_msg(msg);
#endif
	    i = 0;
	    if (acornscsi_write_pio(host, msg->msg, &i, msg->length, 1000000))
		printk("scsi%d: timeout while sending message\n", host->host->host_no);

	    host->scsi.last_message = msg->msg[0];
	    if (msg->msg[0] == EXTENDED_MESSAGE)
		host->scsi.last_message |= msg->msg[2] << 8;

	    if (i != msg->length)
		break;
	}
	break;
    }
#if (DEBUG & DEBUG_MESSAGES)
    printk("\n");
#endif
}

/*
 * Function: void acornscsi_readstatusbyte(AS_Host *host)
 * Purpose : Read status byte from connected target
 * Params  : host - host connected to target
 */
static
void acornscsi_readstatusbyte(AS_Host *host)
{
    acornscsi_sbic_issuecmd(host, CMND_XFERINFO|CMND_SBT);
    acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "reading status byte");
    host->scsi.SCp.Status = sbic_arm_read(host, SBIC_DATA);
}

/*
 * Function: unsigned char acornscsi_readmessagebyte(AS_Host *host)
 * Purpose : Read one message byte from connected target
 * Params  : host - host connected to target
 */
static
unsigned char acornscsi_readmessagebyte(AS_Host *host)
{
    unsigned char message;

    acornscsi_sbic_issuecmd(host, CMND_XFERINFO | CMND_SBT);

    acornscsi_sbic_wait(host, ASR_DBR, ASR_DBR, 1000, "for message byte");

    message = sbic_arm_read(host, SBIC_DATA);

    /* wait for MSGIN-XFER-PAUSED */
    acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after message byte");

    sbic_arm_read(host, SBIC_SSR);

    return message;
}

/*
 * Function: void acornscsi_message(AS_Host *host)
 * Purpose : Read complete message from connected target & action message
 * Params  : host - host connected to target
 */
static
void acornscsi_message(AS_Host *host)
{
    unsigned char message[16];
    unsigned int msgidx = 0, msglen = 1;

    do {
	message[msgidx] = acornscsi_readmessagebyte(host);

	switch (msgidx) {
	case 0:
	    if (message[0] == EXTENDED_MESSAGE ||
		(message[0] >= 0x20 && message[0] <= 0x2f))
		msglen = 2;
	    break;

	case 1:
	    if (message[0] == EXTENDED_MESSAGE)
		msglen += message[msgidx];
	    break;
	}
	msgidx += 1;
	if (msgidx < msglen) {
	    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);

	    /* wait for next msg-in */
	    acornscsi_sbic_wait(host, ASR_INT, ASR_INT, 1000, "for interrupt after negate ack");
	    sbic_arm_read(host, SBIC_SSR);
	}
    } while (msgidx < msglen);

#if (DEBUG & DEBUG_MESSAGES)
    printk("scsi%d.%c: message in: ",
	    host->host->host_no, acornscsi_target(host));
    spi_print_msg(message);
    printk("\n");
#endif

    if (host->scsi.phase == PHASE_RECONNECTED) {
	/*
	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.17)
	 * 'Whenever a target reconnects to an initiator to continue
	 *  a tagged I/O process, the SIMPLE QUEUE TAG message shall
	 *  be sent immediately following the IDENTIFY message...'
	 */
	if (message[0] == SIMPLE_QUEUE_TAG)
	    host->scsi.reconnected.tag = message[1];
	if (acornscsi_reconnect_finish(host))
	    host->scsi.phase = PHASE_MSGIN;
    }

    switch (message[0]) {
    case ABORT:
    case ABORT_TAG:
    case COMMAND_COMPLETE:
	if (host->scsi.phase != PHASE_STATUSIN) {
	    printk(KERN_ERR "scsi%d.%c: command complete following non-status in phase?\n",
		    host->host->host_no, acornscsi_target(host));
	    acornscsi_dumplog(host, host->SCpnt->device->id);
	}
	host->scsi.phase = PHASE_DONE;
	host->scsi.SCp.Message = message[0];
	break;

    case SAVE_POINTERS:
	/*
	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.20)
	 * 'The SAVE DATA POINTER message is sent from a target to
	 *  direct the initiator to copy the active data pointer to
	 *  the saved data pointer for the current I/O process.
	 */
	acornscsi_dma_cleanup(host);
	host->SCpnt->SCp = host->scsi.SCp;
	host->SCpnt->SCp.sent_command = 0;
	host->scsi.phase = PHASE_MSGIN;
	break;

    case RESTORE_POINTERS:
	/*
	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.19)
	 * 'The RESTORE POINTERS message is sent from a target to
	 *  direct the initiator to copy the most recently saved
	 *  command, data, and status pointers for the I/O process
	 *  to the corresponding active pointers.  The command and
	 *  status pointers shall be restored to the beginning of
	 *  the present command and status areas.'
	 */
	acornscsi_dma_cleanup(host);
	host->scsi.SCp = host->SCpnt->SCp;
	host->scsi.phase = PHASE_MSGIN;
	break;

    case DISCONNECT:
	/*
	 * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 6.4.2)
	 * 'On those occasions when an error or exception condition occurs
	 *  and the target elects to repeat the information transfer, the
	 *  target may repeat the transfer either issuing a RESTORE POINTERS
	 *  message or by disconnecting without issuing a SAVE POINTERS
	 *  message.  When reconnection is completed, the most recent
	 *  saved pointer values are restored.'
	 */
	acornscsi_dma_cleanup(host);
	host->scsi.phase = PHASE_DISCONNECT;
	break;

    case MESSAGE_REJECT:
#if 0 /* this isn't needed any more */
	/*
	 * If we were negociating sync transfer, we don't yet know if
	 * this REJECT is for the sync transfer or for the tagged queue/wide
	 * transfer.  Re-initiate sync transfer negotiation now, and if
	 * we got a REJECT in response to SDTR, then it'll be set to DONE.
	 */
	if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST)
	    host->device[host->SCpnt->device->id].sync_state = SYNC_NEGOCIATE;
#endif

	/*
	 * If we have any messages waiting to go out, then assert ATN now
	 */
	if (msgqueue_msglength(&host->scsi.msgs))
	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);

	switch (host->scsi.last_message) {
#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
	case HEAD_OF_QUEUE_TAG:
	case ORDERED_QUEUE_TAG:
	case SIMPLE_QUEUE_TAG:
	    /*
	     * ANSI standard says: (Section SCSI-2 Rev. 10c Sect 5.6.17)
	     *  If a target does not implement tagged queuing and a queue tag
	     *  message is received, it shall respond with a MESSAGE REJECT
	     *  message and accept the I/O process as if it were untagged.
	     */
	    printk(KERN_NOTICE "scsi%d.%c: disabling tagged queueing\n",
		    host->host->host_no, acornscsi_target(host));
	    host->SCpnt->device->simple_tags = 0;
	    set_bit(host->SCpnt->device->id * 8 + host->SCpnt->device->lun, host->busyluns);
	    break;
#endif
	case EXTENDED_MESSAGE | (EXTENDED_SDTR << 8):
	    /*
	     * Target can't handle synchronous transfers
	     */
	    printk(KERN_NOTICE "scsi%d.%c: Using asynchronous transfer\n",
		    host->host->host_no, acornscsi_target(host));
	    host->device[host->SCpnt->device->id].sync_xfer = SYNCHTRANSFER_2DBA;
	    host->device[host->SCpnt->device->id].sync_state = SYNC_ASYNCHRONOUS;
	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
	    break;

	default:
	    break;
	}
	break;

    case QUEUE_FULL:
	/* TODO: target queue is full */
	break;

    case SIMPLE_QUEUE_TAG:
	/* tag queue reconnect... message[1] = queue tag.  Print something to indicate something happened! */
	printk("scsi%d.%c: reconnect queue tag %02X\n",
		host->host->host_no, acornscsi_target(host),
		message[1]);
	break;

    case EXTENDED_MESSAGE:
	switch (message[2]) {
#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
	case EXTENDED_SDTR:
	    if (host->device[host->SCpnt->device->id].sync_state == SYNC_SENT_REQUEST) {
		/*
		 * We requested synchronous transfers.  This isn't quite right...
		 * We can only say if this succeeded if we proceed on to execute the
		 * command from this message.  If we get a MESSAGE PARITY ERROR,
		 * and the target retries fail, then we fallback to asynchronous mode
		 */
		host->device[host->SCpnt->device->id].sync_state = SYNC_COMPLETED;
		printk(KERN_NOTICE "scsi%d.%c: Using synchronous transfer, offset %d, %d ns\n",
			host->host->host_no, acornscsi_target(host),
			message[4], message[3] * 4);
		host->device[host->SCpnt->device->id].sync_xfer =
			calc_sync_xfer(message[3] * 4, message[4]);
	    } else {
		unsigned char period, length;
		/*
		 * Target requested synchronous transfers.  The agreement is only
		 * to be in operation AFTER the target leaves message out phase.
		 */
		acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
		period = max_t(unsigned int, message[3], sdtr_period / 4);
		length = min_t(unsigned int, message[4], sdtr_size);
		msgqueue_addmsg(&host->scsi.msgs, 5, EXTENDED_MESSAGE, 3,
				 EXTENDED_SDTR, period, length);
		host->device[host->SCpnt->device->id].sync_xfer =
			calc_sync_xfer(period * 4, length);
	    }
	    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
	    break;
#else
	    /* We do not accept synchronous transfers.  Respond with a
	     * MESSAGE_REJECT.
	     */
#endif

	case EXTENDED_WDTR:
	    /* The WD33C93A is only 8-bit.  We respond with a MESSAGE_REJECT
	     * to a wide data transfer request.
	     */
	default:
	    acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
	    msgqueue_flush(&host->scsi.msgs);
	    msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
	    break;
	}
	break;

#ifdef CONFIG_SCSI_ACORNSCSI_LINK
    case LINKED_CMD_COMPLETE:
    case LINKED_FLG_CMD_COMPLETE:
	/*
	 * We don't support linked commands yet
	 */
	if (0) {
#if (DEBUG & DEBUG_LINK)
	    printk("scsi%d.%c: lun %d tag %d linked command complete\n",
		    host->host->host_no, acornscsi_target(host), host->SCpnt->tag);
#endif
	    /*
	     * A linked command should only terminate with one of these messages
	     * if there are more linked commands available.
	     */
	    if (!host->SCpnt->next_link) {
		printk(KERN_WARNING "scsi%d.%c: lun %d tag %d linked command complete, but no next_link\n",
			instance->host_no, acornscsi_target(host), host->SCpnt->tag);
		acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
		msgqueue_addmsg(&host->scsi.msgs, 1, ABORT);
	    } else {
		struct scsi_cmnd *SCpnt = host->SCpnt;

		acornscsi_dma_cleanup(host);

		host->SCpnt = host->SCpnt->next_link;
		host->SCpnt->tag = SCpnt->tag;
		SCpnt->result = DID_OK | host->scsi.SCp.Message << 8 | host->Scsi.SCp.Status;
		SCpnt->done(SCpnt);

		/* initialise host->SCpnt->SCp */
	    }
	    break;
	}
#endif

    default: /* reject message */
	printk(KERN_ERR "scsi%d.%c: unrecognised message %02X, rejecting\n",
		host->host->host_no, acornscsi_target(host),
		message[0]);
	acornscsi_sbic_issuecmd(host, CMND_ASSERTATN);
	msgqueue_flush(&host->scsi.msgs);
	msgqueue_addmsg(&host->scsi.msgs, 1, MESSAGE_REJECT);
	host->scsi.phase = PHASE_MSGIN;
	break;
    }
    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
}

/*
 * Function: int acornscsi_buildmessages(AS_Host *host)
 * Purpose : build the connection messages for a host
 * Params  : host - host to add messages to
 */
static
void acornscsi_buildmessages(AS_Host *host)
{
#if 0
    /* does the device need resetting? */
    if (cmd_reset) {
	msgqueue_addmsg(&host->scsi.msgs, 1, BUS_DEVICE_RESET);
	return;
    }
#endif

    msgqueue_addmsg(&host->scsi.msgs, 1,
		     IDENTIFY(host->device[host->SCpnt->device->id].disconnect_ok,
			     host->SCpnt->device->lun));

#if 0
    /* does the device need the current command aborted */
    if (cmd_aborted) {
	acornscsi_abortcmd(host->SCpnt->tag);
	return;
    }
#endif

#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
    if (host->SCpnt->tag) {
	unsigned int tag_type;

	if (host->SCpnt->cmnd[0] == REQUEST_SENSE ||
	    host->SCpnt->cmnd[0] == TEST_UNIT_READY ||
	    host->SCpnt->cmnd[0] == INQUIRY)
	    tag_type = HEAD_OF_QUEUE_TAG;
	else
	    tag_type = SIMPLE_QUEUE_TAG;
	msgqueue_addmsg(&host->scsi.msgs, 2, tag_type, host->SCpnt->tag);
    }
#endif

#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
    if (host->device[host->SCpnt->device->id].sync_state == SYNC_NEGOCIATE) {
	host->device[host->SCpnt->device->id].sync_state = SYNC_SENT_REQUEST;
	msgqueue_addmsg(&host->scsi.msgs, 5,
			 EXTENDED_MESSAGE, 3, EXTENDED_SDTR,
			 sdtr_period / 4, sdtr_size);
    }
#endif
}

/*
 * Function: int acornscsi_starttransfer(AS_Host *host)
 * Purpose : transfer data to/from connected target
 * Params  : host - host to which target is connected
 * Returns : 0 if failure
 */
static
int acornscsi_starttransfer(AS_Host *host)
{
    int residual;

    if (!host->scsi.SCp.ptr /*&& host->scsi.SCp.this_residual*/) {
	printk(KERN_ERR "scsi%d.%c: null buffer passed to acornscsi_starttransfer\n",
		host->host->host_no, acornscsi_target(host));
	return 0;
    }

    residual = scsi_bufflen(host->SCpnt) - host->scsi.SCp.scsi_xferred;

    sbic_arm_write(host, SBIC_SYNCHTRANSFER, host->device[host->SCpnt->device->id].sync_xfer);
    sbic_arm_writenext(host, residual >> 16);
    sbic_arm_writenext(host, residual >> 8);
    sbic_arm_writenext(host, residual);
    acornscsi_sbic_issuecmd(host, CMND_XFERINFO);
    return 1;
}

/* =========================================================================================
 * Connection & Disconnection
 */
/*
 * Function : acornscsi_reconnect(AS_Host *host)
 * Purpose  : reconnect a previously disconnected command
 * Params   : host - host specific data
 * Remarks  : SCSI spec says:
 *		'The set of active pointers is restored from the set
 *		 of saved pointers upon reconnection of the I/O process'
 */
static
int acornscsi_reconnect(AS_Host *host)
{
    unsigned int target, lun, ok = 0;

    target = sbic_arm_read(host, SBIC_SOURCEID);

    if (!(target & 8))
	printk(KERN_ERR "scsi%d: invalid source id after reselection "
		"- device fault?\n",
		host->host->host_no);

    target &= 7;

    if (host->SCpnt && !host->scsi.disconnectable) {
	printk(KERN_ERR "scsi%d.%d: reconnected while command in "
		"progress to target %d?\n",
		host->host->host_no, target, host->SCpnt->device->id);
	host->SCpnt = NULL;
    }

    lun = sbic_arm_read(host, SBIC_DATA) & 7;

    host->scsi.reconnected.target = target;
    host->scsi.reconnected.lun = lun;
    host->scsi.reconnected.tag = 0;

    if (host->scsi.disconnectable && host->SCpnt &&
	host->SCpnt->device->id == target && host->SCpnt->device->lun == lun)
	ok = 1;

    if (!ok && queue_probetgtlun(&host->queues.disconnected, target, lun))
	ok = 1;

    ADD_STATUS(target, 0x81, host->scsi.phase, 0);

    if (ok) {
	host->scsi.phase = PHASE_RECONNECTED;
    } else {
	/* this doesn't seem to work */
	printk(KERN_ERR "scsi%d.%c: reselected with no command "
		"to reconnect with\n",
		host->host->host_no, '0' + target);
	acornscsi_dumplog(host, target);
	acornscsi_abortcmd(host, 0);
	if (host->SCpnt) {
	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
	    host->SCpnt = NULL;
	}
    }
    acornscsi_sbic_issuecmd(host, CMND_NEGATEACK);
    return !ok;
}

/*
 * Function: int acornscsi_reconect_finish(AS_Host *host)
 * Purpose : finish reconnecting a command
 * Params  : host - host to complete
 * Returns : 0 if failed
 */
static
int acornscsi_reconnect_finish(AS_Host *host)
{
    if (host->scsi.disconnectable && host->SCpnt) {
	host->scsi.disconnectable = 0;
	if (host->SCpnt->device->id  == host->scsi.reconnected.target &&
	    host->SCpnt->device->lun == host->scsi.reconnected.lun &&
	    host->SCpnt->tag         == host->scsi.reconnected.tag) {
#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
	    DBG(host->SCpnt, printk("scsi%d.%c: reconnected",
		    host->host->host_no, acornscsi_target(host)));
#endif
	} else {
	    queue_add_cmd_tail(&host->queues.disconnected, host->SCpnt);
#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
	    DBG(host->SCpnt, printk("scsi%d.%c: had to move command "
		    "to disconnected queue\n",
		    host->host->host_no, acornscsi_target(host)));
#endif
	    host->SCpnt = NULL;
	}
    }
    if (!host->SCpnt) {
	host->SCpnt = queue_remove_tgtluntag(&host->queues.disconnected,
				host->scsi.reconnected.target,
				host->scsi.reconnected.lun,
				host->scsi.reconnected.tag);
#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
	DBG(host->SCpnt, printk("scsi%d.%c: had to get command",
		host->host->host_no, acornscsi_target(host)));
#endif
    }

    if (!host->SCpnt)
	acornscsi_abortcmd(host, host->scsi.reconnected.tag);
    else {
	/*
	 * Restore data pointer from SAVED pointers.
	 */
	host->scsi.SCp = host->SCpnt->SCp;
#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
	printk(", data pointers: [%p, %X]",
		host->scsi.SCp.ptr, host->scsi.SCp.this_residual);
#endif
    }
#if (DEBUG & (DEBUG_QUEUES|DEBUG_DISCON))
    printk("\n");
#endif

    host->dma.transferred = host->scsi.SCp.scsi_xferred;

    return host->SCpnt != NULL;
}

/*
 * Function: void acornscsi_disconnect_unexpected(AS_Host *host)
 * Purpose : handle an unexpected disconnect
 * Params  : host - host on which disconnect occurred
 */
static
void acornscsi_disconnect_unexpected(AS_Host *host)
{
    printk(KERN_ERR "scsi%d.%c: unexpected disconnect\n",
	    host->host->host_no, acornscsi_target(host));
#if (DEBUG & DEBUG_ABORT)
    acornscsi_dumplog(host, 8);
#endif

    acornscsi_done(host, &host->SCpnt, DID_ERROR);
}

/*
 * Function: void acornscsi_abortcmd(AS_host *host, unsigned char tag)
 * Purpose : abort a currently executing command
 * Params  : host - host with connected command to abort
 *	     tag  - tag to abort
 */
static
void acornscsi_abortcmd(AS_Host *host, unsigned char tag)
{
    host->scsi.phase = PHASE_ABORTED;
    sbic_arm_write(host, SBIC_CMND, CMND_ASSERTATN);

    msgqueue_flush(&host->scsi.msgs);
#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
    if (tag)
	msgqueue_addmsg(&host->scsi.msgs, 2, ABORT_TAG, tag);
    else
#endif
	msgqueue_addmsg(&host->scsi.msgs, 1, ABORT);
}

/* ==========================================================================================
 * Interrupt routines.
 */
/*
 * Function: int acornscsi_sbicintr(AS_Host *host)
 * Purpose : handle interrupts from SCSI device
 * Params  : host - host to process
 * Returns : INTR_PROCESS if expecting another SBIC interrupt
 *	     INTR_IDLE if no interrupt
 *	     INTR_NEXT_COMMAND if we have finished processing the command
 */
static
intr_ret_t acornscsi_sbicintr(AS_Host *host, int in_irq)
{
    unsigned int asr, ssr;

    asr = sbic_arm_read(host, SBIC_ASR);
    if (!(asr & ASR_INT))
	return INTR_IDLE;

    ssr = sbic_arm_read(host, SBIC_SSR);

#if (DEBUG & DEBUG_PHASES)
    print_sbic_status(asr, ssr, host->scsi.phase);
#endif

    ADD_STATUS(8, ssr, host->scsi.phase, in_irq);

    if (host->SCpnt && !host->scsi.disconnectable)
	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);

    switch (ssr) {
    case 0x00:				/* reset state - not advanced			*/
	printk(KERN_ERR "scsi%d: reset in standard mode but wanted advanced mode.\n",
		host->host->host_no);
	/* setup sbic - WD33C93A */
	sbic_arm_write(host, SBIC_OWNID, OWNID_EAF | host->host->this_id);
	sbic_arm_write(host, SBIC_CMND, CMND_RESET);
	return INTR_IDLE;

    case 0x01:				/* reset state - advanced			*/
	sbic_arm_write(host, SBIC_CTRL, INIT_SBICDMA | CTRL_IDI);
	sbic_arm_write(host, SBIC_TIMEOUT, TIMEOUT_TIME);
	sbic_arm_write(host, SBIC_SYNCHTRANSFER, SYNCHTRANSFER_2DBA);
	sbic_arm_write(host, SBIC_SOURCEID, SOURCEID_ER | SOURCEID_DSP);
	msgqueue_flush(&host->scsi.msgs);
	return INTR_IDLE;

    case 0x41:				/* unexpected disconnect aborted command	*/
	acornscsi_disconnect_unexpected(host);
	return INTR_NEXT_COMMAND;
    }

    switch (host->scsi.phase) {
    case PHASE_CONNECTING:		/* STATE: command removed from issue queue	*/
	switch (ssr) {
	case 0x11:			/* -> PHASE_CONNECTED				*/
	    /* BUS FREE -> SELECTION */
	    host->scsi.phase = PHASE_CONNECTED;
	    msgqueue_flush(&host->scsi.msgs);
	    host->dma.transferred = host->scsi.SCp.scsi_xferred;
	    /* 33C93 gives next interrupt indicating bus phase */
	    asr = sbic_arm_read(host, SBIC_ASR);
	    if (!(asr & ASR_INT))
		break;
	    ssr = sbic_arm_read(host, SBIC_SSR);
	    ADD_STATUS(8, ssr, host->scsi.phase, 1);
	    ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, 1);
	    goto connected;
	    
	case 0x42:			/* select timed out				*/
					/* -> PHASE_IDLE				*/
	    acornscsi_done(host, &host->SCpnt, DID_NO_CONNECT);
	    return INTR_NEXT_COMMAND;

	case 0x81:			/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
	    /* BUS FREE -> RESELECTION */
	    host->origSCpnt = host->SCpnt;
	    host->SCpnt = NULL;
	    msgqueue_flush(&host->scsi.msgs);
	    acornscsi_reconnect(host);
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTING, SSR %02X?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	    acornscsi_abortcmd(host, host->SCpnt->tag);
	}
	return INTR_PROCESSING;

    connected:
    case PHASE_CONNECTED:		/* STATE: device selected ok			*/
	switch (ssr) {
#ifdef NONSTANDARD
	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
	    /* SELECTION -> COMMAND */
	    acornscsi_sendcommand(host);
	    break;

	case 0x8b:			/* -> PHASE_STATUS				*/
	    /* SELECTION -> STATUS */
	    acornscsi_readstatusbyte(host);
	    host->scsi.phase = PHASE_STATUSIN;
	    break;
#endif

	case 0x8e:			/* -> PHASE_MSGOUT				*/
	    /* SELECTION ->MESSAGE OUT */
	    host->scsi.phase = PHASE_MSGOUT;
	    acornscsi_buildmessages(host);
	    acornscsi_sendmessage(host);
	    break;

	/* these should not happen */
	case 0x85:			/* target disconnected				*/
	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_CONNECTED, SSR %02X?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	    acornscsi_abortcmd(host, host->SCpnt->tag);
	}
	return INTR_PROCESSING;

    case PHASE_MSGOUT:			/* STATE: connected & sent IDENTIFY message	*/
	/*
	 * SCSI standard says that MESSAGE OUT phases can be followed by a
	 * DATA phase, STATUS phase, MESSAGE IN phase or COMMAND phase
	 */
	switch (ssr) {
	case 0x8a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
	case 0x1a:			/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
	    /* MESSAGE OUT -> COMMAND */
	    acornscsi_sendcommand(host);
	    break;

	case 0x8b:			/* -> PHASE_STATUS				*/
	case 0x1b:			/* -> PHASE_STATUS				*/
	    /* MESSAGE OUT -> STATUS */
	    acornscsi_readstatusbyte(host);
	    host->scsi.phase = PHASE_STATUSIN;
	    break;

	case 0x8e:			/* -> PHASE_MSGOUT				*/
	    /* MESSAGE_OUT(MESSAGE_IN) ->MESSAGE OUT */
	    acornscsi_sendmessage(host);
	    break;

	case 0x4f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
	    /* MESSAGE OUT -> MESSAGE IN */
	    acornscsi_message(host);
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGOUT, SSR %02X?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    case PHASE_COMMAND: 		/* STATE: connected & command sent		*/
	switch (ssr) {
	case 0x18:			/* -> PHASE_DATAOUT				*/
	    /* COMMAND -> DATA OUT */
	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
		acornscsi_abortcmd(host, host->SCpnt->tag);
	    acornscsi_dma_setup(host, DMA_OUT);
	    if (!acornscsi_starttransfer(host))
		acornscsi_abortcmd(host, host->SCpnt->tag);
	    host->scsi.phase = PHASE_DATAOUT;
	    return INTR_IDLE;

	case 0x19:			/* -> PHASE_DATAIN				*/
	    /* COMMAND -> DATA IN */
	    if (host->scsi.SCp.sent_command != host->SCpnt->cmd_len)
		acornscsi_abortcmd(host, host->SCpnt->tag);
	    acornscsi_dma_setup(host, DMA_IN);
	    if (!acornscsi_starttransfer(host))
		acornscsi_abortcmd(host, host->SCpnt->tag);
	    host->scsi.phase = PHASE_DATAIN;
	    return INTR_IDLE;

	case 0x1b:			/* -> PHASE_STATUS				*/
	    /* COMMAND -> STATUS */
	    acornscsi_readstatusbyte(host);
	    host->scsi.phase = PHASE_STATUSIN;
	    break;

	case 0x1e:			/* -> PHASE_MSGOUT				*/
	    /* COMMAND -> MESSAGE OUT */
	    acornscsi_sendmessage(host);
	    break;

	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
	    /* COMMAND -> MESSAGE IN */
	    acornscsi_message(host);
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_COMMAND, SSR %02X?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    case PHASE_DISCONNECT:		/* STATE: connected, received DISCONNECT msg	*/
	if (ssr == 0x85) {		/* -> PHASE_IDLE				*/
	    host->scsi.disconnectable = 1;
	    host->scsi.reconnected.tag = 0;
	    host->scsi.phase = PHASE_IDLE;
	    host->stats.disconnects += 1;
	} else {
	    printk(KERN_ERR "scsi%d.%c: PHASE_DISCONNECT, SSR %02X instead of disconnect?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_NEXT_COMMAND;

    case PHASE_IDLE:			/* STATE: disconnected				*/
	if (ssr == 0x81)		/* -> PHASE_RECONNECTED or PHASE_ABORTED	*/
	    acornscsi_reconnect(host);
	else {
	    printk(KERN_ERR "scsi%d.%c: PHASE_IDLE, SSR %02X while idle?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    case PHASE_RECONNECTED:		/* STATE: device reconnected to initiator	*/
	/*
	 * Command reconnected - if MESGIN, get message - it may be
	 * the tag.  If not, get command out of disconnected queue
	 */
	/*
	 * If we reconnected and we're not in MESSAGE IN phase after IDENTIFY,
	 * reconnect I_T_L command
	 */
	if (ssr != 0x8f && !acornscsi_reconnect_finish(host))
	    return INTR_IDLE;
	ADD_STATUS(host->SCpnt->device->id, ssr, host->scsi.phase, in_irq);
	switch (ssr) {
	case 0x88:			/* data out phase				*/
					/* -> PHASE_DATAOUT				*/
	    /* MESSAGE IN -> DATA OUT */
	    acornscsi_dma_setup(host, DMA_OUT);
	    if (!acornscsi_starttransfer(host))
		acornscsi_abortcmd(host, host->SCpnt->tag);
	    host->scsi.phase = PHASE_DATAOUT;
	    return INTR_IDLE;

	case 0x89:			/* data in phase				*/
					/* -> PHASE_DATAIN				*/
	    /* MESSAGE IN -> DATA IN */
	    acornscsi_dma_setup(host, DMA_IN);
	    if (!acornscsi_starttransfer(host))
		acornscsi_abortcmd(host, host->SCpnt->tag);
	    host->scsi.phase = PHASE_DATAIN;
	    return INTR_IDLE;

	case 0x8a:			/* command out					*/
	    /* MESSAGE IN -> COMMAND */
	    acornscsi_sendcommand(host);/* -> PHASE_COMMAND, PHASE_COMMANDPAUSED	*/
	    break;

	case 0x8b:			/* status in					*/
					/* -> PHASE_STATUSIN				*/
	    /* MESSAGE IN -> STATUS */
	    acornscsi_readstatusbyte(host);
	    host->scsi.phase = PHASE_STATUSIN;
	    break;

	case 0x8e:			/* message out					*/
					/* -> PHASE_MSGOUT				*/
	    /* MESSAGE IN -> MESSAGE OUT */
	    acornscsi_sendmessage(host);
	    break;

	case 0x8f:			/* message in					*/
	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_RECONNECTED, SSR %02X after reconnect?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    case PHASE_DATAIN:			/* STATE: transferred data in			*/
	/*
	 * This is simple - if we disconnect then the DMA address & count is
	 * correct.
	 */
	switch (ssr) {
	case 0x19:			/* -> PHASE_DATAIN				*/
	case 0x89:			/* -> PHASE_DATAIN				*/
	    acornscsi_abortcmd(host, host->SCpnt->tag);
	    return INTR_IDLE;

	case 0x1b:			/* -> PHASE_STATUSIN				*/
	case 0x4b:			/* -> PHASE_STATUSIN				*/
	case 0x8b:			/* -> PHASE_STATUSIN				*/
	    /* DATA IN -> STATUS */
	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
					  acornscsi_sbic_xfcount(host);
	    acornscsi_dma_stop(host);
	    acornscsi_readstatusbyte(host);
	    host->scsi.phase = PHASE_STATUSIN;
	    break;

	case 0x1e:			/* -> PHASE_MSGOUT				*/
	case 0x4e:			/* -> PHASE_MSGOUT				*/
	case 0x8e:			/* -> PHASE_MSGOUT				*/
	    /* DATA IN -> MESSAGE OUT */
	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
					  acornscsi_sbic_xfcount(host);
	    acornscsi_dma_stop(host);
	    acornscsi_sendmessage(host);
	    break;

	case 0x1f:			/* message in					*/
	case 0x4f:			/* message in					*/
	case 0x8f:			/* message in					*/
	    /* DATA IN -> MESSAGE IN */
	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
					  acornscsi_sbic_xfcount(host);
	    acornscsi_dma_stop(host);
	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAIN, SSR %02X?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    case PHASE_DATAOUT: 		/* STATE: transferred data out			*/
	/*
	 * This is more complicated - if we disconnect, the DMA could be 12
	 * bytes ahead of us.  We need to correct this.
	 */
	switch (ssr) {
	case 0x18:			/* -> PHASE_DATAOUT				*/
	case 0x88:			/* -> PHASE_DATAOUT				*/
	    acornscsi_abortcmd(host, host->SCpnt->tag);
	    return INTR_IDLE;

	case 0x1b:			/* -> PHASE_STATUSIN				*/
	case 0x4b:			/* -> PHASE_STATUSIN				*/
	case 0x8b:			/* -> PHASE_STATUSIN				*/
	    /* DATA OUT -> STATUS */
	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
					  acornscsi_sbic_xfcount(host);
	    acornscsi_dma_stop(host);
	    acornscsi_dma_adjust(host);
	    acornscsi_readstatusbyte(host);
	    host->scsi.phase = PHASE_STATUSIN;
	    break;

	case 0x1e:			/* -> PHASE_MSGOUT				*/
	case 0x4e:			/* -> PHASE_MSGOUT				*/
	case 0x8e:			/* -> PHASE_MSGOUT				*/
	    /* DATA OUT -> MESSAGE OUT */
	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
					  acornscsi_sbic_xfcount(host);
	    acornscsi_dma_stop(host);
	    acornscsi_dma_adjust(host);
	    acornscsi_sendmessage(host);
	    break;

	case 0x1f:			/* message in					*/
	case 0x4f:			/* message in					*/
	case 0x8f:			/* message in					*/
	    /* DATA OUT -> MESSAGE IN */
	    host->scsi.SCp.scsi_xferred = scsi_bufflen(host->SCpnt) -
					  acornscsi_sbic_xfcount(host);
	    acornscsi_dma_stop(host);
	    acornscsi_dma_adjust(host);
	    acornscsi_message(host);	/* -> PHASE_MSGIN, PHASE_DISCONNECT		*/
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_DATAOUT, SSR %02X?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    case PHASE_STATUSIN:		/* STATE: status in complete			*/
	switch (ssr) {
	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
	case 0x8f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
	    /* STATUS -> MESSAGE IN */
	    acornscsi_message(host);
	    break;

	case 0x1e:			/* -> PHASE_MSGOUT				*/
	case 0x8e:			/* -> PHASE_MSGOUT				*/
	    /* STATUS -> MESSAGE OUT */
	    acornscsi_sendmessage(host);
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_STATUSIN, SSR %02X instead of MESSAGE_IN?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    case PHASE_MSGIN:			/* STATE: message in				*/
	switch (ssr) {
	case 0x1e:			/* -> PHASE_MSGOUT				*/
	case 0x4e:			/* -> PHASE_MSGOUT				*/
	case 0x8e:			/* -> PHASE_MSGOUT				*/
	    /* MESSAGE IN -> MESSAGE OUT */
	    acornscsi_sendmessage(host);
	    break;

	case 0x1f:			/* -> PHASE_MSGIN, PHASE_DONE, PHASE_DISCONNECT */
	case 0x2f:
	case 0x4f:
	case 0x8f:
	    acornscsi_message(host);
	    break;

	case 0x85:
	    printk("scsi%d.%c: strange message in disconnection\n",
		host->host->host_no, acornscsi_target(host));
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	    acornscsi_done(host, &host->SCpnt, DID_ERROR);
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_MSGIN, SSR %02X after message in?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    case PHASE_DONE:			/* STATE: received status & message		*/
	switch (ssr) {
	case 0x85:			/* -> PHASE_IDLE				*/
	    acornscsi_done(host, &host->SCpnt, DID_OK);
	    return INTR_NEXT_COMMAND;

	case 0x1e:
	case 0x8e:
	    acornscsi_sendmessage(host);
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_DONE, SSR %02X instead of disconnect?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    case PHASE_ABORTED:
	switch (ssr) {
	case 0x85:
	    if (host->SCpnt)
		acornscsi_done(host, &host->SCpnt, DID_ABORT);
	    else {
		clear_bit(host->scsi.reconnected.target * 8 + host->scsi.reconnected.lun,
			  host->busyluns);
		host->scsi.phase = PHASE_IDLE;
	    }
	    return INTR_NEXT_COMMAND;

	case 0x1e:
	case 0x2e:
	case 0x4e:
	case 0x8e:
	    acornscsi_sendmessage(host);
	    break;

	default:
	    printk(KERN_ERR "scsi%d.%c: PHASE_ABORTED, SSR %02X?\n",
		    host->host->host_no, acornscsi_target(host), ssr);
	    acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
	}
	return INTR_PROCESSING;

    default:
	printk(KERN_ERR "scsi%d.%c: unknown driver phase %d\n",
		host->host->host_no, acornscsi_target(host), ssr);
	acornscsi_dumplog(host, host->SCpnt ? host->SCpnt->device->id : 8);
    }
    return INTR_PROCESSING;
}

/*
 * Prototype: void acornscsi_intr(int irq, void *dev_id)
 * Purpose  : handle interrupts from Acorn SCSI card
 * Params   : irq    - interrupt number
 *	      dev_id - device specific data (AS_Host structure)
 */
static irqreturn_t
acornscsi_intr(int irq, void *dev_id)
{
    AS_Host *host = (AS_Host *)dev_id;
    intr_ret_t ret;
    int iostatus;
    int in_irq = 0;

    do {
	ret = INTR_IDLE;

	iostatus = readb(host->fast + INT_REG);

	if (iostatus & 2) {
	    acornscsi_dma_intr(host);
	    iostatus = readb(host->fast + INT_REG);
	}

	if (iostatus & 8)
	    ret = acornscsi_sbicintr(host, in_irq);

	/*
	 * If we have a transfer pending, start it.
	 * Only start it if the interface has already started transferring
	 * it's data
	 */
	if (host->dma.xfer_required)
	    acornscsi_dma_xfer(host);

	if (ret == INTR_NEXT_COMMAND)
	    ret = acornscsi_kick(host);

	in_irq = 1;
    } while (ret != INTR_IDLE);

    return IRQ_HANDLED;
}

/*=============================================================================================
 * Interfaces between interrupt handler and rest of scsi code
 */

/*
 * Function : acornscsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
 * Purpose  : queues a SCSI command
 * Params   : cmd  - SCSI command
 *	      done - function called on completion, with pointer to command descriptor
 * Returns  : 0, or < 0 on error.
 */
static int acornscsi_queuecmd_lck(struct scsi_cmnd *SCpnt,
		       void (*done)(struct scsi_cmnd *))
{
    AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;

    if (!done) {
	/* there should be some way of rejecting errors like this without panicing... */
	panic("scsi%d: queuecommand called with NULL done function [cmd=%p]",
		host->host->host_no, SCpnt);
	return -EINVAL;
    }

#if (DEBUG & DEBUG_NO_WRITE)
    if (acornscsi_cmdtype(SCpnt->cmnd[0]) == CMD_WRITE && (NO_WRITE & (1 << SCpnt->device->id))) {
	printk(KERN_CRIT "scsi%d.%c: WRITE attempted with NO_WRITE flag set\n",
	    host->host->host_no, '0' + SCpnt->device->id);
	SCpnt->result = DID_NO_CONNECT << 16;
	done(SCpnt);
	return 0;
    }
#endif

    SCpnt->scsi_done = done;
    SCpnt->host_scribble = NULL;
    SCpnt->result = 0;
    SCpnt->tag = 0;
    SCpnt->SCp.phase = (int)acornscsi_datadirection(SCpnt->cmnd[0]);
    SCpnt->SCp.sent_command = 0;
    SCpnt->SCp.scsi_xferred = 0;

    init_SCp(SCpnt);

    host->stats.queues += 1;

    {
	unsigned long flags;

	if (!queue_add_cmd_ordered(&host->queues.issue, SCpnt)) {
	    SCpnt->result = DID_ERROR << 16;
	    done(SCpnt);
	    return 0;
	}
	local_irq_save(flags);
	if (host->scsi.phase == PHASE_IDLE)
	    acornscsi_kick(host);
	local_irq_restore(flags);
    }
    return 0;
}

DEF_SCSI_QCMD(acornscsi_queuecmd)

/*
 * Prototype: void acornscsi_reportstatus(struct scsi_cmnd **SCpntp1, struct scsi_cmnd **SCpntp2, int result)
 * Purpose  : pass a result to *SCpntp1, and check if *SCpntp1 = *SCpntp2
 * Params   : SCpntp1 - pointer to command to return
 *	      SCpntp2 - pointer to command to check
 *	      result  - result to pass back to mid-level done function
 * Returns  : *SCpntp2 = NULL if *SCpntp1 is the same command structure as *SCpntp2.
 */
static inline void acornscsi_reportstatus(struct scsi_cmnd **SCpntp1,
					  struct scsi_cmnd **SCpntp2,
					  int result)
{
	struct scsi_cmnd *SCpnt = *SCpntp1;

    if (SCpnt) {
	*SCpntp1 = NULL;

	SCpnt->result = result;
	SCpnt->scsi_done(SCpnt);
    }

    if (SCpnt == *SCpntp2)
	*SCpntp2 = NULL;
}

enum res_abort { res_not_running, res_success, res_success_clear, res_snooze };

/*
 * Prototype: enum res acornscsi_do_abort(struct scsi_cmnd *SCpnt)
 * Purpose  : abort a command on this host
 * Params   : SCpnt - command to abort
 * Returns  : our abort status
 */
static enum res_abort acornscsi_do_abort(AS_Host *host, struct scsi_cmnd *SCpnt)
{
	enum res_abort res = res_not_running;

	if (queue_remove_cmd(&host->queues.issue, SCpnt)) {
		/*
		 * The command was on the issue queue, and has not been
		 * issued yet.  We can remove the command from the queue,
		 * and acknowledge the abort.  Neither the devices nor the
		 * interface know about the command.
		 */
//#if (DEBUG & DEBUG_ABORT)
		printk("on issue queue ");
//#endif
		res = res_success;
	} else if (queue_remove_cmd(&host->queues.disconnected, SCpnt)) {
		/*
		 * The command was on the disconnected queue.  Simply
		 * acknowledge the abort condition, and when the target
		 * reconnects, we will give it an ABORT message.  The
		 * target should then disconnect, and we will clear
		 * the busylun bit.
		 */
//#if (DEBUG & DEBUG_ABORT)
		printk("on disconnected queue ");
//#endif
		res = res_success;
	} else if (host->SCpnt == SCpnt) {
		unsigned long flags;

//#if (DEBUG & DEBUG_ABORT)
		printk("executing ");
//#endif

		local_irq_save(flags);
		switch (host->scsi.phase) {
		/*
		 * If the interface is idle, and the command is 'disconnectable',
		 * then it is the same as on the disconnected queue.  We simply
		 * remove all traces of the command.  When the target reconnects,
		 * we will give it an ABORT message since the command could not
		 * be found.  When the target finally disconnects, we will clear
		 * the busylun bit.
		 */
		case PHASE_IDLE:
			if (host->scsi.disconnectable) {
				host->scsi.disconnectable = 0;
				host->SCpnt = NULL;
				res = res_success;
			}
			break;

		/*
		 * If the command has connected and done nothing further,
		 * simply force a disconnect.  We also need to clear the
		 * busylun bit.
		 */
		case PHASE_CONNECTED:
			sbic_arm_write(host, SBIC_CMND, CMND_DISCONNECT);
			host->SCpnt = NULL;
			res = res_success_clear;
			break;

		default:
			acornscsi_abortcmd(host, host->SCpnt->tag);
			res = res_snooze;
		}
		local_irq_restore(flags);
	} else if (host->origSCpnt == SCpnt) {
		/*
		 * The command will be executed next, but a command
		 * is currently using the interface.  This is similar to
		 * being on the issue queue, except the busylun bit has
		 * been set.
		 */
		host->origSCpnt = NULL;
//#if (DEBUG & DEBUG_ABORT)
		printk("waiting for execution ");
//#endif
		res = res_success_clear;
	} else
		printk("unknown ");

	return res;
}

/*
 * Prototype: int acornscsi_abort(struct scsi_cmnd *SCpnt)
 * Purpose  : abort a command on this host
 * Params   : SCpnt - command to abort
 * Returns  : one of SCSI_ABORT_ macros
 */
int acornscsi_abort(struct scsi_cmnd *SCpnt)
{
	AS_Host *host = (AS_Host *) SCpnt->device->host->hostdata;
	int result;

	host->stats.aborts += 1;

#if (DEBUG & DEBUG_ABORT)
	{
		int asr, ssr;
		asr = sbic_arm_read(host, SBIC_ASR);
		ssr = sbic_arm_read(host, SBIC_SSR);

		printk(KERN_WARNING "acornscsi_abort: ");
		print_sbic_status(asr, ssr, host->scsi.phase);
		acornscsi_dumplog(host, SCpnt->device->id);
	}
#endif

	printk("scsi%d: ", host->host->host_no);

	switch (acornscsi_do_abort(host, SCpnt)) {
	/*
	 * We managed to find the command and cleared it out.
	 * We do not expect the command to be executing on the
	 * target, but we have set the busylun bit.
	 */
	case res_success_clear:
//#if (DEBUG & DEBUG_ABORT)
		printk("clear ");
//#endif
		clear_bit(SCpnt->device->id * 8 + SCpnt->device->lun, host->busyluns);

	/*
	 * We found the command, and cleared it out.  Either
	 * the command is still known to be executing on the
	 * target, or the busylun bit is not set.
	 */
	case res_success:
//#if (DEBUG & DEBUG_ABORT)
		printk("success\n");
//#endif
		result = SUCCESS;
		break;

	/*
	 * We did find the command, but unfortunately we couldn't
	 * unhook it from ourselves.  Wait some more, and if it
	 * still doesn't complete, reset the interface.
	 */
	case res_snooze:
//#if (DEBUG & DEBUG_ABORT)
		printk("snooze\n");
//#endif
		result = FAILED;
		break;

	/*
	 * The command could not be found (either because it completed,
	 * or it got dropped.
	 */
	default:
	case res_not_running:
		acornscsi_dumplog(host, SCpnt->device->id);
		result = FAILED;
//#if (DEBUG & DEBUG_ABORT)
		printk("not running\n");
//#endif
		break;
	}

	return result;
}

/*
 * Prototype: int acornscsi_reset(struct scsi_cmnd *SCpnt)
 * Purpose  : reset a command on this host/reset this host
 * Params   : SCpnt  - command causing reset
 * Returns  : one of SCSI_RESET_ macros
 */
int acornscsi_bus_reset(struct scsi_cmnd *SCpnt)
{
	AS_Host *host = (AS_Host *)SCpnt->device->host->hostdata;
	struct scsi_cmnd *SCptr;
    
    host->stats.resets += 1;

#if (DEBUG & DEBUG_RESET)
    {
	int asr, ssr;

	asr = sbic_arm_read(host, SBIC_ASR);
	ssr = sbic_arm_read(host, SBIC_SSR);

	printk(KERN_WARNING "acornscsi_reset: ");
	print_sbic_status(asr, ssr, host->scsi.phase);
	acornscsi_dumplog(host, SCpnt->device->id);
    }
#endif

    acornscsi_dma_stop(host);

    /*
     * do hard reset.  This resets all devices on this host, and so we
     * must set the reset status on all commands.
     */
    acornscsi_resetcard(host);

    while ((SCptr = queue_remove(&host->queues.disconnected)) != NULL)
	;

    return SUCCESS;
}

/*==============================================================================================
 * initialisation & miscellaneous support
 */

/*
 * Function: char *acornscsi_info(struct Scsi_Host *host)
 * Purpose : return a string describing this interface
 * Params  : host - host to give information on
 * Returns : a constant string
 */
const
char *acornscsi_info(struct Scsi_Host *host)
{
    static char string[100], *p;

    p = string;
    
    p += sprintf(string, "%s at port %08lX irq %d v%d.%d.%d"
#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
    " SYNC"
#endif
#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
    " TAG"
#endif
#ifdef CONFIG_SCSI_ACORNSCSI_LINK
    " LINK"
#endif
#if (DEBUG & DEBUG_NO_WRITE)
    " NOWRITE (" __stringify(NO_WRITE) ")"
#endif
		, host->hostt->name, host->io_port, host->irq,
		VER_MAJOR, VER_MINOR, VER_PATCH);
    return string;
}

int acornscsi_proc_info(struct Scsi_Host *instance, char *buffer, char **start, off_t offset,
			int length, int inout)
{
    int pos, begin = 0, devidx;
    struct scsi_device *scd;
    AS_Host *host;
    char *p = buffer;

    if (inout == 1)
	return -EINVAL;

    host  = (AS_Host *)instance->hostdata;
    
    p += sprintf(p, "AcornSCSI driver v%d.%d.%d"
#ifdef CONFIG_SCSI_ACORNSCSI_SYNC
    " SYNC"
#endif
#ifdef CONFIG_SCSI_ACORNSCSI_TAGGED_QUEUE
    " TAG"
#endif
#ifdef CONFIG_SCSI_ACORNSCSI_LINK
    " LINK"
#endif
#if (DEBUG & DEBUG_NO_WRITE)
    " NOWRITE (" __stringify(NO_WRITE) ")"
#endif
		"\n\n", VER_MAJOR, VER_MINOR, VER_PATCH);

    p += sprintf(p,	"SBIC: WD33C93A  Address: %p    IRQ : %d\n",
			host->base + SBIC_REGIDX, host->scsi.irq);
#ifdef USE_DMAC
    p += sprintf(p,	"DMAC: uPC71071  Address: %p  IRQ : %d\n\n",
			host->base + DMAC_OFFSET, host->scsi.irq);
#endif

    p += sprintf(p,	"Statistics:\n"
			"Queued commands: %-10u    Issued commands: %-10u\n"
			"Done commands  : %-10u    Reads          : %-10u\n"
			"Writes         : %-10u    Others         : %-10u\n"
			"Disconnects    : %-10u    Aborts         : %-10u\n"
			"Resets         : %-10u\n\nLast phases:",
			host->stats.queues,		host->stats.removes,
			host->stats.fins,		host->stats.reads,
			host->stats.writes,		host->stats.miscs,
			host->stats.disconnects,	host->stats.aborts,
			host->stats.resets);

    for (devidx = 0; devidx < 9; devidx ++) {
	unsigned int statptr, prev;

	p += sprintf(p, "\n%c:", devidx == 8 ? 'H' : ('0' + devidx));
	statptr = host->status_ptr[devidx] - 10;

	if ((signed int)statptr < 0)
	    statptr += STATUS_BUFFER_SIZE;

	prev = host->status[devidx][statptr].when;

	for (; statptr != host->status_ptr[devidx]; statptr = (statptr + 1) & (STATUS_BUFFER_SIZE - 1)) {
	    if (host->status[devidx][statptr].when) {
		p += sprintf(p, "%c%02X:%02X+%2ld",
			host->status[devidx][statptr].irq ? '-' : ' ',
			host->status[devidx][statptr].ph,
			host->status[devidx][statptr].ssr,
			(host->status[devidx][statptr].when - prev) < 100 ?
				(host->status[devidx][statptr].when - prev) : 99);
		prev = host->status[devidx][statptr].when;
	    }
	}
    }

    p += sprintf(p, "\nAttached devices:\n");

    shost_for_each_device(scd, instance) {
	p += sprintf(p, "Device/Lun TaggedQ      Sync\n");
	p += sprintf(p, "     %d/%d   ", scd->id, scd->lun);
	if (scd->tagged_supported)
		p += sprintf(p, "%3sabled(%3d) ",
			     scd->simple_tags ? "en" : "dis",
			     scd->current_tag);
	else
		p += sprintf(p, "unsupported  ");

	if (host->device[scd->id].sync_xfer & 15)
		p += sprintf(p, "offset %d, %d ns\n",
			     host->device[scd->id].sync_xfer & 15,
			     acornscsi_getperiod(host->device[scd->id].sync_xfer));
	else
		p += sprintf(p, "async\n");

	pos = p - buffer;
	if (pos + begin < offset) {
	    begin += pos;
	    p = buffer;
	}
	pos = p - buffer;
	if (pos + begin > offset + length) {
	    scsi_device_put(scd);
	    break;
	}
    }

    pos = p - buffer;

    *start = buffer + (offset - begin);
    pos -= offset - begin;

    if (pos > length)
	pos = length;

    return pos;
}

static struct scsi_host_template acornscsi_template = {
	.module			= THIS_MODULE,
	.proc_info		= acornscsi_proc_info,
	.name			= "AcornSCSI",
	.info			= acornscsi_info,
	.queuecommand		= acornscsi_queuecmd,
	.eh_abort_handler	= acornscsi_abort,
	.eh_bus_reset_handler	= acornscsi_bus_reset,
	.can_queue		= 16,
	.this_id		= 7,
	.sg_tablesize		= SG_ALL,
	.cmd_per_lun		= 2,
	.use_clustering		= DISABLE_CLUSTERING,
	.proc_name		= "acornscsi",
};

static int __devinit
acornscsi_probe(struct expansion_card *ec, const struct ecard_id *id)
{
	struct Scsi_Host *host;
	AS_Host *ashost;
	int ret;

	ret = ecard_request_resources(ec);
	if (ret)
		goto out;

	host = scsi_host_alloc(&acornscsi_template, sizeof(AS_Host));
	if (!host) {
		ret = -ENOMEM;
		goto out_release;
	}

	ashost = (AS_Host *)host->hostdata;

	ashost->base = ecardm_iomap(ec, ECARD_RES_MEMC, 0, 0);
	ashost->fast = ecardm_iomap(ec, ECARD_RES_IOCFAST, 0, 0);
	if (!ashost->base || !ashost->fast)
		goto out_put;

	host->irq = ec->irq;
	ashost->host = host;
	ashost->scsi.irq = host->irq;

	ec->irqaddr	= ashost->fast + INT_REG;
	ec->irqmask	= 0x0a;

	ret = request_irq(host->irq, acornscsi_intr, IRQF_DISABLED, "acornscsi", ashost);
	if (ret) {
		printk(KERN_CRIT "scsi%d: IRQ%d not free: %d\n",
			host->host_no, ashost->scsi.irq, ret);
		goto out_put;
	}

	memset(&ashost->stats, 0, sizeof (ashost->stats));
	queue_initialise(&ashost->queues.issue);
	queue_initialise(&ashost->queues.disconnected);
	msgqueue_initialise(&ashost->scsi.msgs);

	acornscsi_resetcard(ashost);

	ret = scsi_add_host(host, &ec->dev);
	if (ret)
		goto out_irq;

	scsi_scan_host(host);
	goto out;

 out_irq:
	free_irq(host->irq, ashost);
	msgqueue_free(&ashost->scsi.msgs);
	queue_free(&ashost->queues.disconnected);
	queue_free(&ashost->queues.issue);
 out_put:
	ecardm_iounmap(ec, ashost->fast);
	ecardm_iounmap(ec, ashost->base);
	scsi_host_put(host);
 out_release:
	ecard_release_resources(ec);
 out:
	return ret;
}

static void __devexit acornscsi_remove(struct expansion_card *ec)
{
	struct Scsi_Host *host = ecard_get_drvdata(ec);
	AS_Host *ashost = (AS_Host *)host->hostdata;

	ecard_set_drvdata(ec, NULL);
	scsi_remove_host(host);

	/*
	 * Put card into RESET state
	 */
	writeb(0x80, ashost->fast + PAGE_REG);

	free_irq(host->irq, ashost);

	msgqueue_free(&ashost->scsi.msgs);
	queue_free(&ashost->queues.disconnected);
	queue_free(&ashost->queues.issue);
	ecardm_iounmap(ec, ashost->fast);
	ecardm_iounmap(ec, ashost->base);
	scsi_host_put(host);
	ecard_release_resources(ec);
}

static const struct ecard_id acornscsi_cids[] = {
	{ MANU_ACORN, PROD_ACORN_SCSI },
	{ 0xffff, 0xffff },
};

static struct ecard_driver acornscsi_driver = {
	.probe		= acornscsi_probe,
	.remove		= __devexit_p(acornscsi_remove),
	.id_table	= acornscsi_cids,
	.drv = {
		.name		= "acornscsi",
	},
};

static int __init acornscsi_init(void)
{
	return ecard_register_driver(&acornscsi_driver);
}

static void __exit acornscsi_exit(void)
{
	ecard_remove_driver(&acornscsi_driver);
}

module_init(acornscsi_init);
module_exit(acornscsi_exit);

MODULE_AUTHOR("Russell King");
MODULE_DESCRIPTION("AcornSCSI driver");
MODULE_LICENSE("GPL");