summaryrefslogtreecommitdiff
path: root/drivers/scsi/aic7xxx/aic7xxx_osm.c
blob: 2e9c38f2e8a68d1065be272baa7174fa2eb06e90 (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
/*
 * Adaptec AIC7xxx device driver for Linux.
 *
 * $Id: //depot/aic7xxx/linux/drivers/scsi/aic7xxx/aic7xxx_osm.c#235 $
 *
 * Copyright (c) 1994 John Aycock
 *   The University of Calgary Department of Computer Science.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Sources include the Adaptec 1740 driver (aha1740.c), the Ultrastor 24F
 * driver (ultrastor.c), various Linux kernel source, the Adaptec EISA
 * config file (!adp7771.cfg), the Adaptec AHA-2740A Series User's Guide,
 * the Linux Kernel Hacker's Guide, Writing a SCSI Device Driver for Linux,
 * the Adaptec 1542 driver (aha1542.c), the Adaptec EISA overlay file
 * (adp7770.ovl), the Adaptec AHA-2740 Series Technical Reference Manual,
 * the Adaptec AIC-7770 Data Book, the ANSI SCSI specification, the
 * ANSI SCSI-2 specification (draft 10c), ...
 *
 * --------------------------------------------------------------------------
 *
 *  Modifications by Daniel M. Eischen (deischen@iworks.InterWorks.org):
 *
 *  Substantially modified to include support for wide and twin bus
 *  adapters, DMAing of SCBs, tagged queueing, IRQ sharing, bug fixes,
 *  SCB paging, and other rework of the code.
 *
 * --------------------------------------------------------------------------
 * Copyright (c) 1994-2000 Justin T. Gibbs.
 * Copyright (c) 2000-2001 Adaptec Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 *
 *---------------------------------------------------------------------------
 *
 *  Thanks also go to (in alphabetical order) the following:
 *
 *    Rory Bolt     - Sequencer bug fixes
 *    Jay Estabrook - Initial DEC Alpha support
 *    Doug Ledford  - Much needed abort/reset bug fixes
 *    Kai Makisara  - DMAing of SCBs
 *
 *  A Boot time option was also added for not resetting the scsi bus.
 *
 *    Form:  aic7xxx=extended
 *           aic7xxx=no_reset
 *           aic7xxx=verbose
 *
 *  Daniel M. Eischen, deischen@iworks.InterWorks.org, 1/23/97
 *
 *  Id: aic7xxx.c,v 4.1 1997/06/12 08:23:42 deang Exp
 */

/*
 * Further driver modifications made by Doug Ledford <dledford@redhat.com>
 *
 * Copyright (c) 1997-1999 Doug Ledford
 *
 * These changes are released under the same licensing terms as the FreeBSD
 * driver written by Justin Gibbs.  Please see his Copyright notice above
 * for the exact terms and conditions covering my changes as well as the
 * warranty statement.
 *
 * Modifications made to the aic7xxx.c,v 4.1 driver from Dan Eischen include
 * but are not limited to:
 *
 *  1: Import of the latest FreeBSD sequencer code for this driver
 *  2: Modification of kernel code to accommodate different sequencer semantics
 *  3: Extensive changes throughout kernel portion of driver to improve
 *     abort/reset processing and error hanndling
 *  4: Other work contributed by various people on the Internet
 *  5: Changes to printk information and verbosity selection code
 *  6: General reliability related changes, especially in IRQ management
 *  7: Modifications to the default probe/attach order for supported cards
 *  8: SMP friendliness has been improved
 *
 */

#include "aic7xxx_osm.h"
#include "aic7xxx_inline.h"
#include <scsi/scsicam.h>

static struct scsi_transport_template *ahc_linux_transport_template = NULL;

#include <linux/init.h>		/* __setup */
#include <linux/mm.h>		/* For fetching system memory size */
#include <linux/blkdev.h>		/* For block_size() */
#include <linux/delay.h>	/* For ssleep/msleep */


/*
 * Set this to the delay in seconds after SCSI bus reset.
 * Note, we honor this only for the initial bus reset.
 * The scsi error recovery code performs its own bus settle
 * delay handling for error recovery actions.
 */
#ifdef CONFIG_AIC7XXX_RESET_DELAY_MS
#define AIC7XXX_RESET_DELAY CONFIG_AIC7XXX_RESET_DELAY_MS
#else
#define AIC7XXX_RESET_DELAY 5000
#endif

/*
 * Control collection of SCSI transfer statistics for the /proc filesystem.
 *
 * NOTE: Do NOT enable this when running on kernels version 1.2.x and below.
 * NOTE: This does affect performance since it has to maintain statistics.
 */
#ifdef CONFIG_AIC7XXX_PROC_STATS
#define AIC7XXX_PROC_STATS
#endif

/*
 * To change the default number of tagged transactions allowed per-device,
 * add a line to the lilo.conf file like:
 * append="aic7xxx=verbose,tag_info:{{32,32,32,32},{32,32,32,32}}"
 * which will result in the first four devices on the first two
 * controllers being set to a tagged queue depth of 32.
 *
 * The tag_commands is an array of 16 to allow for wide and twin adapters.
 * Twin adapters will use indexes 0-7 for channel 0, and indexes 8-15
 * for channel 1.
 */
typedef struct {
	uint8_t tag_commands[16];	/* Allow for wide/twin adapters. */
} adapter_tag_info_t;

/*
 * Modify this as you see fit for your system.
 *
 * 0			tagged queuing disabled
 * 1 <= n <= 253	n == max tags ever dispatched.
 *
 * The driver will throttle the number of commands dispatched to a
 * device if it returns queue full.  For devices with a fixed maximum
 * queue depth, the driver will eventually determine this depth and
 * lock it in (a console message is printed to indicate that a lock
 * has occurred).  On some devices, queue full is returned for a temporary
 * resource shortage.  These devices will return queue full at varying
 * depths.  The driver will throttle back when the queue fulls occur and
 * attempt to slowly increase the depth over time as the device recovers
 * from the resource shortage.
 *
 * In this example, the first line will disable tagged queueing for all
 * the devices on the first probed aic7xxx adapter.
 *
 * The second line enables tagged queueing with 4 commands/LUN for IDs
 * (0, 2-11, 13-15), disables tagged queueing for ID 12, and tells the
 * driver to attempt to use up to 64 tags for ID 1.
 *
 * The third line is the same as the first line.
 *
 * The fourth line disables tagged queueing for devices 0 and 3.  It
 * enables tagged queueing for the other IDs, with 16 commands/LUN
 * for IDs 1 and 4, 127 commands/LUN for ID 8, and 4 commands/LUN for
 * IDs 2, 5-7, and 9-15.
 */

/*
 * NOTE: The below structure is for reference only, the actual structure
 *       to modify in order to change things is just below this comment block.
adapter_tag_info_t aic7xxx_tag_info[] =
{
	{{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
	{{4, 64, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 0, 4, 4, 4}},
	{{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
	{{0, 16, 4, 0, 16, 4, 4, 4, 127, 4, 4, 4, 4, 4, 4, 4}}
};
*/

#ifdef CONFIG_AIC7XXX_CMDS_PER_DEVICE
#define AIC7XXX_CMDS_PER_DEVICE CONFIG_AIC7XXX_CMDS_PER_DEVICE
#else
#define AIC7XXX_CMDS_PER_DEVICE AHC_MAX_QUEUE
#endif

#define AIC7XXX_CONFIGED_TAG_COMMANDS {					\
	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,		\
	AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE		\
}

/*
 * By default, use the number of commands specified by
 * the users kernel configuration.
 */
static adapter_tag_info_t aic7xxx_tag_info[] =
{
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS},
	{AIC7XXX_CONFIGED_TAG_COMMANDS}
};

/*
 * There should be a specific return value for this in scsi.h, but
 * it seems that most drivers ignore it.
 */
#define DID_UNDERFLOW   DID_ERROR

void
ahc_print_path(struct ahc_softc *ahc, struct scb *scb)
{
	printk("(scsi%d:%c:%d:%d): ",
	       ahc->platform_data->host->host_no,
	       scb != NULL ? SCB_GET_CHANNEL(ahc, scb) : 'X',
	       scb != NULL ? SCB_GET_TARGET(ahc, scb) : -1,
	       scb != NULL ? SCB_GET_LUN(scb) : -1);
}

/*
 * XXX - these options apply unilaterally to _all_ 274x/284x/294x
 *       cards in the system.  This should be fixed.  Exceptions to this
 *       rule are noted in the comments.
 */

/*
 * Skip the scsi bus reset.  Non 0 make us skip the reset at startup.  This
 * has no effect on any later resets that might occur due to things like
 * SCSI bus timeouts.
 */
static uint32_t aic7xxx_no_reset;

/*
 * Should we force EXTENDED translation on a controller.
 *     0 == Use whatever is in the SEEPROM or default to off
 *     1 == Use whatever is in the SEEPROM or default to on
 */
static uint32_t aic7xxx_extended;

/*
 * PCI bus parity checking of the Adaptec controllers.  This is somewhat
 * dubious at best.  To my knowledge, this option has never actually
 * solved a PCI parity problem, but on certain machines with broken PCI
 * chipset configurations where stray PCI transactions with bad parity are
 * the norm rather than the exception, the error messages can be overwelming.
 * It's included in the driver for completeness.
 *   0	   = Shut off PCI parity check
 *   non-0 = reverse polarity pci parity checking
 */
static uint32_t aic7xxx_pci_parity = ~0;

/*
 * There are lots of broken chipsets in the world.  Some of them will
 * violate the PCI spec when we issue byte sized memory writes to our
 * controller.  I/O mapped register access, if allowed by the given
 * platform, will work in almost all cases.
 */
uint32_t aic7xxx_allow_memio = ~0;

/*
 * So that we can set how long each device is given as a selection timeout.
 * The table of values goes like this:
 *   0 - 256ms
 *   1 - 128ms
 *   2 - 64ms
 *   3 - 32ms
 * We default to 256ms because some older devices need a longer time
 * to respond to initial selection.
 */
static uint32_t aic7xxx_seltime;

/*
 * Certain devices do not perform any aging on commands.  Should the
 * device be saturated by commands in one portion of the disk, it is
 * possible for transactions on far away sectors to never be serviced.
 * To handle these devices, we can periodically send an ordered tag to
 * force all outstanding transactions to be serviced prior to a new
 * transaction.
 */
static uint32_t aic7xxx_periodic_otag;

/*
 * Module information and settable options.
 */
static char *aic7xxx = NULL;

MODULE_AUTHOR("Maintainer: Justin T. Gibbs <gibbs@scsiguy.com>");
MODULE_DESCRIPTION("Adaptec Aic77XX/78XX SCSI Host Bus Adapter driver");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_VERSION(AIC7XXX_DRIVER_VERSION);
module_param(aic7xxx, charp, 0444);
MODULE_PARM_DESC(aic7xxx,
"period-delimited options string:\n"
"	verbose			Enable verbose/diagnostic logging\n"
"	allow_memio		Allow device registers to be memory mapped\n"
"	debug			Bitmask of debug values to enable\n"
"	no_probe		Toggle EISA/VLB controller probing\n"
"	probe_eisa_vl		Toggle EISA/VLB controller probing\n"
"	no_reset		Supress initial bus resets\n"
"	extended		Enable extended geometry on all controllers\n"
"	periodic_otag		Send an ordered tagged transaction\n"
"				periodically to prevent tag starvation.\n"
"				This may be required by some older disk\n"
"				drives or RAID arrays.\n"
"	tag_info:<tag_str>	Set per-target tag depth\n"
"	global_tag_depth:<int>	Global tag depth for every target\n"
"				on every bus\n"
"	seltime:<int>		Selection Timeout\n"
"				(0/256ms,1/128ms,2/64ms,3/32ms)\n"
"\n"
"	Sample /etc/modprobe.conf line:\n"
"		Toggle EISA/VLB probing\n"
"		Set tag depth on Controller 1/Target 1 to 10 tags\n"
"		Shorten the selection timeout to 128ms\n"
"\n"
"	options aic7xxx 'aic7xxx=probe_eisa_vl.tag_info:{{}.{.10}}.seltime:1'\n"
);

static void ahc_linux_handle_scsi_status(struct ahc_softc *,
					 struct scsi_device *,
					 struct scb *);
static void ahc_linux_queue_cmd_complete(struct ahc_softc *ahc,
					 struct scsi_cmnd *cmd);
static void ahc_linux_freeze_simq(struct ahc_softc *ahc);
static void ahc_linux_release_simq(struct ahc_softc *ahc);
static int  ahc_linux_queue_recovery_cmd(struct scsi_cmnd *cmd, scb_flag flag);
static void ahc_linux_initialize_scsi_bus(struct ahc_softc *ahc);
static u_int ahc_linux_user_tagdepth(struct ahc_softc *ahc,
				     struct ahc_devinfo *devinfo);
static void ahc_linux_device_queue_depth(struct scsi_device *);
static int ahc_linux_run_command(struct ahc_softc*,
				 struct ahc_linux_device *,
				 struct scsi_cmnd *);
static void ahc_linux_setup_tag_info_global(char *p);
static int  aic7xxx_setup(char *s);

static int ahc_linux_unit;


/********************************* Inlines ************************************/
static __inline void ahc_linux_unmap_scb(struct ahc_softc*, struct scb*);

static __inline int ahc_linux_map_seg(struct ahc_softc *ahc, struct scb *scb,
		 		      struct ahc_dma_seg *sg,
				      dma_addr_t addr, bus_size_t len);

static __inline void
ahc_linux_unmap_scb(struct ahc_softc *ahc, struct scb *scb)
{
	struct scsi_cmnd *cmd;

	cmd = scb->io_ctx;
	ahc_sync_sglist(ahc, scb, BUS_DMASYNC_POSTWRITE);

	scsi_dma_unmap(cmd);
}

static __inline int
ahc_linux_map_seg(struct ahc_softc *ahc, struct scb *scb,
		  struct ahc_dma_seg *sg, dma_addr_t addr, bus_size_t len)
{
	int	 consumed;

	if ((scb->sg_count + 1) > AHC_NSEG)
		panic("Too few segs for dma mapping.  "
		      "Increase AHC_NSEG\n");

	consumed = 1;
	sg->addr = ahc_htole32(addr & 0xFFFFFFFF);
	scb->platform_data->xfer_len += len;

	if (sizeof(dma_addr_t) > 4
	 && (ahc->flags & AHC_39BIT_ADDRESSING) != 0)
		len |= (addr >> 8) & AHC_SG_HIGH_ADDR_MASK;

	sg->len = ahc_htole32(len);
	return (consumed);
}

/*
 * Return a string describing the driver.
 */
static const char *
ahc_linux_info(struct Scsi_Host *host)
{
	static char buffer[512];
	char	ahc_info[256];
	char   *bp;
	struct ahc_softc *ahc;

	bp = &buffer[0];
	ahc = *(struct ahc_softc **)host->hostdata;
	memset(bp, 0, sizeof(buffer));
	strcpy(bp, "Adaptec AIC7XXX EISA/VLB/PCI SCSI HBA DRIVER, Rev ");
	strcat(bp, AIC7XXX_DRIVER_VERSION);
	strcat(bp, "\n");
	strcat(bp, "        <");
	strcat(bp, ahc->description);
	strcat(bp, ">\n");
	strcat(bp, "        ");
	ahc_controller_info(ahc, ahc_info);
	strcat(bp, ahc_info);
	strcat(bp, "\n");

	return (bp);
}

/*
 * Queue an SCB to the controller.
 */
static int
ahc_linux_queue(struct scsi_cmnd * cmd, void (*scsi_done) (struct scsi_cmnd *))
{
	struct	 ahc_softc *ahc;
	struct	 ahc_linux_device *dev = scsi_transport_device_data(cmd->device);
	int rtn = SCSI_MLQUEUE_HOST_BUSY;
	unsigned long flags;

	ahc = *(struct ahc_softc **)cmd->device->host->hostdata;

	ahc_lock(ahc, &flags);
	if (ahc->platform_data->qfrozen == 0) {
		cmd->scsi_done = scsi_done;
		cmd->result = CAM_REQ_INPROG << 16;
		rtn = ahc_linux_run_command(ahc, dev, cmd);
	}
	ahc_unlock(ahc, &flags);

	return rtn;
}

static inline struct scsi_target **
ahc_linux_target_in_softc(struct scsi_target *starget)
{
	struct	ahc_softc *ahc =
		*((struct ahc_softc **)dev_to_shost(&starget->dev)->hostdata);
	unsigned int target_offset;

	target_offset = starget->id;
	if (starget->channel != 0)
		target_offset += 8;

	return &ahc->platform_data->starget[target_offset];
}

static int
ahc_linux_target_alloc(struct scsi_target *starget)
{
	struct	ahc_softc *ahc =
		*((struct ahc_softc **)dev_to_shost(&starget->dev)->hostdata);
	struct seeprom_config *sc = ahc->seep_config;
	unsigned long flags;
	struct scsi_target **ahc_targp = ahc_linux_target_in_softc(starget);
	unsigned short scsirate;
	struct ahc_devinfo devinfo;
	struct ahc_initiator_tinfo *tinfo;
	struct ahc_tmode_tstate *tstate;
	char channel = starget->channel + 'A';
	unsigned int our_id = ahc->our_id;
	unsigned int target_offset;

	target_offset = starget->id;
	if (starget->channel != 0)
		target_offset += 8;
	  
	if (starget->channel)
		our_id = ahc->our_id_b;

	ahc_lock(ahc, &flags);

	BUG_ON(*ahc_targp != NULL);

	*ahc_targp = starget;

	if (sc) {
		int maxsync = AHC_SYNCRATE_DT;
		int ultra = 0;
		int flags = sc->device_flags[target_offset];

		if (ahc->flags & AHC_NEWEEPROM_FMT) {
		    if (flags & CFSYNCHISULTRA)
			ultra = 1;
		} else if (flags & CFULTRAEN)
			ultra = 1;
		/* AIC nutcase; 10MHz appears as ultra = 1, CFXFER = 0x04
		 * change it to ultra=0, CFXFER = 0 */
		if(ultra && (flags & CFXFER) == 0x04) {
			ultra = 0;
			flags &= ~CFXFER;
		}
	    
		if ((ahc->features & AHC_ULTRA2) != 0) {
			scsirate = (flags & CFXFER) | (ultra ? 0x8 : 0);
		} else {
			scsirate = (flags & CFXFER) << 4;
			maxsync = ultra ? AHC_SYNCRATE_ULTRA : 
				AHC_SYNCRATE_FAST;
		}
		spi_max_width(starget) = (flags & CFWIDEB) ? 1 : 0;
		if (!(flags & CFSYNCH))
			spi_max_offset(starget) = 0;
		spi_min_period(starget) = 
			ahc_find_period(ahc, scsirate, maxsync);

		tinfo = ahc_fetch_transinfo(ahc, channel, ahc->our_id,
					    starget->id, &tstate);
	}
	ahc_compile_devinfo(&devinfo, our_id, starget->id,
			    CAM_LUN_WILDCARD, channel,
			    ROLE_INITIATOR);
	ahc_set_syncrate(ahc, &devinfo, NULL, 0, 0, 0,
			 AHC_TRANS_GOAL, /*paused*/FALSE);
	ahc_set_width(ahc, &devinfo, MSG_EXT_WDTR_BUS_8_BIT,
		      AHC_TRANS_GOAL, /*paused*/FALSE);
	ahc_unlock(ahc, &flags);

	return 0;
}

static void
ahc_linux_target_destroy(struct scsi_target *starget)
{
	struct scsi_target **ahc_targp = ahc_linux_target_in_softc(starget);

	*ahc_targp = NULL;
}

static int
ahc_linux_slave_alloc(struct scsi_device *sdev)
{
	struct	ahc_softc *ahc =
		*((struct ahc_softc **)sdev->host->hostdata);
	struct scsi_target *starget = sdev->sdev_target;
	struct ahc_linux_device *dev;

	if (bootverbose)
		printf("%s: Slave Alloc %d\n", ahc_name(ahc), sdev->id);

	dev = scsi_transport_device_data(sdev);
	memset(dev, 0, sizeof(*dev));

	/*
	 * We start out life using untagged
	 * transactions of which we allow one.
	 */
	dev->openings = 1;

	/*
	 * Set maxtags to 0.  This will be changed if we
	 * later determine that we are dealing with
	 * a tagged queuing capable device.
	 */
	dev->maxtags = 0;
	
	spi_period(starget) = 0;

	return 0;
}

static int
ahc_linux_slave_configure(struct scsi_device *sdev)
{
	struct	ahc_softc *ahc;

	ahc = *((struct ahc_softc **)sdev->host->hostdata);

	if (bootverbose)
		sdev_printk(KERN_INFO, sdev, "Slave Configure\n");

	ahc_linux_device_queue_depth(sdev);

	/* Initial Domain Validation */
	if (!spi_initial_dv(sdev->sdev_target))
		spi_dv_device(sdev);

	return 0;
}

#if defined(__i386__)
/*
 * Return the disk geometry for the given SCSI device.
 */
static int
ahc_linux_biosparam(struct scsi_device *sdev, struct block_device *bdev,
		    sector_t capacity, int geom[])
{
	uint8_t *bh;
	int	 heads;
	int	 sectors;
	int	 cylinders;
	int	 ret;
	int	 extended;
	struct	 ahc_softc *ahc;
	u_int	 channel;

	ahc = *((struct ahc_softc **)sdev->host->hostdata);
	channel = sdev_channel(sdev);

	bh = scsi_bios_ptable(bdev);
	if (bh) {
		ret = scsi_partsize(bh, capacity,
				    &geom[2], &geom[0], &geom[1]);
		kfree(bh);
		if (ret != -1)
			return (ret);
	}
	heads = 64;
	sectors = 32;
	cylinders = aic_sector_div(capacity, heads, sectors);

	if (aic7xxx_extended != 0)
		extended = 1;
	else if (channel == 0)
		extended = (ahc->flags & AHC_EXTENDED_TRANS_A) != 0;
	else
		extended = (ahc->flags & AHC_EXTENDED_TRANS_B) != 0;
	if (extended && cylinders >= 1024) {
		heads = 255;
		sectors = 63;
		cylinders = aic_sector_div(capacity, heads, sectors);
	}
	geom[0] = heads;
	geom[1] = sectors;
	geom[2] = cylinders;
	return (0);
}
#endif

/*
 * Abort the current SCSI command(s).
 */
static int
ahc_linux_abort(struct scsi_cmnd *cmd)
{
	int error;

	error = ahc_linux_queue_recovery_cmd(cmd, SCB_ABORT);
	if (error != 0)
		printf("aic7xxx_abort returns 0x%x\n", error);
	return (error);
}

/*
 * Attempt to send a target reset message to the device that timed out.
 */
static int
ahc_linux_dev_reset(struct scsi_cmnd *cmd)
{
	int error;

	error = ahc_linux_queue_recovery_cmd(cmd, SCB_DEVICE_RESET);
	if (error != 0)
		printf("aic7xxx_dev_reset returns 0x%x\n", error);
	return (error);
}

/*
 * Reset the SCSI bus.
 */
static int
ahc_linux_bus_reset(struct scsi_cmnd *cmd)
{
	struct ahc_softc *ahc;
	int    found;
	unsigned long flags;

	ahc = *(struct ahc_softc **)cmd->device->host->hostdata;

	ahc_lock(ahc, &flags);
	found = ahc_reset_channel(ahc, scmd_channel(cmd) + 'A',
				  /*initiate reset*/TRUE);
	ahc_unlock(ahc, &flags);

	if (bootverbose)
		printf("%s: SCSI bus reset delivered. "
		       "%d SCBs aborted.\n", ahc_name(ahc), found);

	return SUCCESS;
}

struct scsi_host_template aic7xxx_driver_template = {
	.module			= THIS_MODULE,
	.name			= "aic7xxx",
	.proc_name		= "aic7xxx",
	.proc_info		= ahc_linux_proc_info,
	.info			= ahc_linux_info,
	.queuecommand		= ahc_linux_queue,
	.eh_abort_handler	= ahc_linux_abort,
	.eh_device_reset_handler = ahc_linux_dev_reset,
	.eh_bus_reset_handler	= ahc_linux_bus_reset,
#if defined(__i386__)
	.bios_param		= ahc_linux_biosparam,
#endif
	.can_queue		= AHC_MAX_QUEUE,
	.this_id		= -1,
	.max_sectors		= 8192,
	.cmd_per_lun		= 2,
	.use_clustering		= ENABLE_CLUSTERING,
	.slave_alloc		= ahc_linux_slave_alloc,
	.slave_configure	= ahc_linux_slave_configure,
	.target_alloc		= ahc_linux_target_alloc,
	.target_destroy		= ahc_linux_target_destroy,
};

/**************************** Tasklet Handler *********************************/

/******************************** Macros **************************************/
#define BUILD_SCSIID(ahc, cmd)						    \
	((((cmd)->device->id << TID_SHIFT) & TID)			    \
	| (((cmd)->device->channel == 0) ? (ahc)->our_id : (ahc)->our_id_b) \
	| (((cmd)->device->channel == 0) ? 0 : TWIN_CHNLB))

/******************************** Bus DMA *************************************/
int
ahc_dma_tag_create(struct ahc_softc *ahc, bus_dma_tag_t parent,
		   bus_size_t alignment, bus_size_t boundary,
		   dma_addr_t lowaddr, dma_addr_t highaddr,
		   bus_dma_filter_t *filter, void *filterarg,
		   bus_size_t maxsize, int nsegments,
		   bus_size_t maxsegsz, int flags, bus_dma_tag_t *ret_tag)
{
	bus_dma_tag_t dmat;

	dmat = malloc(sizeof(*dmat), M_DEVBUF, M_NOWAIT);
	if (dmat == NULL)
		return (ENOMEM);

	/*
	 * Linux is very simplistic about DMA memory.  For now don't
	 * maintain all specification information.  Once Linux supplies
	 * better facilities for doing these operations, or the
	 * needs of this particular driver change, we might need to do
	 * more here.
	 */
	dmat->alignment = alignment;
	dmat->boundary = boundary;
	dmat->maxsize = maxsize;
	*ret_tag = dmat;
	return (0);
}

void
ahc_dma_tag_destroy(struct ahc_softc *ahc, bus_dma_tag_t dmat)
{
	free(dmat, M_DEVBUF);
}

int
ahc_dmamem_alloc(struct ahc_softc *ahc, bus_dma_tag_t dmat, void** vaddr,
		 int flags, bus_dmamap_t *mapp)
{
	*vaddr = pci_alloc_consistent(ahc->dev_softc,
				      dmat->maxsize, mapp);
	if (*vaddr == NULL)
		return ENOMEM;
	return 0;
}

void
ahc_dmamem_free(struct ahc_softc *ahc, bus_dma_tag_t dmat,
		void* vaddr, bus_dmamap_t map)
{
	pci_free_consistent(ahc->dev_softc, dmat->maxsize,
			    vaddr, map);
}

int
ahc_dmamap_load(struct ahc_softc *ahc, bus_dma_tag_t dmat, bus_dmamap_t map,
		void *buf, bus_size_t buflen, bus_dmamap_callback_t *cb,
		void *cb_arg, int flags)
{
	/*
	 * Assume for now that this will only be used during
	 * initialization and not for per-transaction buffer mapping.
	 */
	bus_dma_segment_t stack_sg;

	stack_sg.ds_addr = map;
	stack_sg.ds_len = dmat->maxsize;
	cb(cb_arg, &stack_sg, /*nseg*/1, /*error*/0);
	return (0);
}

void
ahc_dmamap_destroy(struct ahc_softc *ahc, bus_dma_tag_t dmat, bus_dmamap_t map)
{
}

int
ahc_dmamap_unload(struct ahc_softc *ahc, bus_dma_tag_t dmat, bus_dmamap_t map)
{
	/* Nothing to do */
	return (0);
}

static void
ahc_linux_setup_tag_info_global(char *p)
{
	int tags, i, j;

	tags = simple_strtoul(p + 1, NULL, 0) & 0xff;
	printf("Setting Global Tags= %d\n", tags);

	for (i = 0; i < ARRAY_SIZE(aic7xxx_tag_info); i++) {
		for (j = 0; j < AHC_NUM_TARGETS; j++) {
			aic7xxx_tag_info[i].tag_commands[j] = tags;
		}
	}
}

static void
ahc_linux_setup_tag_info(u_long arg, int instance, int targ, int32_t value)
{

	if ((instance >= 0) && (targ >= 0)
	 && (instance < ARRAY_SIZE(aic7xxx_tag_info))
	 && (targ < AHC_NUM_TARGETS)) {
		aic7xxx_tag_info[instance].tag_commands[targ] = value & 0xff;
		if (bootverbose)
			printf("tag_info[%d:%d] = %d\n", instance, targ, value);
	}
}

static char *
ahc_parse_brace_option(char *opt_name, char *opt_arg, char *end, int depth,
		       void (*callback)(u_long, int, int, int32_t),
		       u_long callback_arg)
{
	char	*tok_end;
	char	*tok_end2;
	int      i;
	int      instance;
	int	 targ;
	int	 done;
	char	 tok_list[] = {'.', ',', '{', '}', '\0'};

	/* All options use a ':' name/arg separator */
	if (*opt_arg != ':')
		return (opt_arg);
	opt_arg++;
	instance = -1;
	targ = -1;
	done = FALSE;
	/*
	 * Restore separator that may be in
	 * the middle of our option argument.
	 */
	tok_end = strchr(opt_arg, '\0');
	if (tok_end < end)
		*tok_end = ',';
	while (!done) {
		switch (*opt_arg) {
		case '{':
			if (instance == -1) {
				instance = 0;
			} else {
				if (depth > 1) {
					if (targ == -1)
						targ = 0;
				} else {
					printf("Malformed Option %s\n",
					       opt_name);
					done = TRUE;
				}
			}
			opt_arg++;
			break;
		case '}':
			if (targ != -1)
				targ = -1;
			else if (instance != -1)
				instance = -1;
			opt_arg++;
			break;
		case ',':
		case '.':
			if (instance == -1)
				done = TRUE;
			else if (targ >= 0)
				targ++;
			else if (instance >= 0)
				instance++;
			opt_arg++;
			break;
		case '\0':
			done = TRUE;
			break;
		default:
			tok_end = end;
			for (i = 0; tok_list[i]; i++) {
				tok_end2 = strchr(opt_arg, tok_list[i]);
				if ((tok_end2) && (tok_end2 < tok_end))
					tok_end = tok_end2;
			}
			callback(callback_arg, instance, targ,
				 simple_strtol(opt_arg, NULL, 0));
			opt_arg = tok_end;
			break;
		}
	}
	return (opt_arg);
}

/*
 * Handle Linux boot parameters. This routine allows for assigning a value
 * to a parameter with a ':' between the parameter and the value.
 * ie. aic7xxx=stpwlev:1,extended
 */
static int
aic7xxx_setup(char *s)
{
	int	i, n;
	char   *p;
	char   *end;

	static struct {
		const char *name;
		uint32_t *flag;
	} options[] = {
		{ "extended", &aic7xxx_extended },
		{ "no_reset", &aic7xxx_no_reset },
		{ "verbose", &aic7xxx_verbose },
		{ "allow_memio", &aic7xxx_allow_memio},
#ifdef AHC_DEBUG
		{ "debug", &ahc_debug },
#endif
		{ "periodic_otag", &aic7xxx_periodic_otag },
		{ "pci_parity", &aic7xxx_pci_parity },
		{ "seltime", &aic7xxx_seltime },
		{ "tag_info", NULL },
		{ "global_tag_depth", NULL },
		{ "dv", NULL }
	};

	end = strchr(s, '\0');

	/*
	 * XXX ia64 gcc isn't smart enough to know that ARRAY_SIZE
	 * will never be 0 in this case.
	 */
	n = 0;

	while ((p = strsep(&s, ",.")) != NULL) {
		if (*p == '\0')
			continue;
		for (i = 0; i < ARRAY_SIZE(options); i++) {

			n = strlen(options[i].name);
			if (strncmp(options[i].name, p, n) == 0)
				break;
		}
		if (i == ARRAY_SIZE(options))
			continue;

		if (strncmp(p, "global_tag_depth", n) == 0) {
			ahc_linux_setup_tag_info_global(p + n);
		} else if (strncmp(p, "tag_info", n) == 0) {
			s = ahc_parse_brace_option("tag_info", p + n, end,
			    2, ahc_linux_setup_tag_info, 0);
		} else if (p[n] == ':') {
			*(options[i].flag) = simple_strtoul(p + n + 1, NULL, 0);
		} else if (strncmp(p, "verbose", n) == 0) {
			*(options[i].flag) = 1;
		} else {
			*(options[i].flag) ^= 0xFFFFFFFF;
		}
	}
	return 1;
}

__setup("aic7xxx=", aic7xxx_setup);

uint32_t aic7xxx_verbose;

int
ahc_linux_register_host(struct ahc_softc *ahc, struct scsi_host_template *template)
{
	char	buf[80];
	struct	Scsi_Host *host;
	char	*new_name;
	u_long	s;
	int	retval;

	template->name = ahc->description;
	host = scsi_host_alloc(template, sizeof(struct ahc_softc *));
	if (host == NULL)
		return (ENOMEM);

	*((struct ahc_softc **)host->hostdata) = ahc;
	ahc->platform_data->host = host;
	host->can_queue = AHC_MAX_QUEUE;
	host->cmd_per_lun = 2;
	/* XXX No way to communicate the ID for multiple channels */
	host->this_id = ahc->our_id;
	host->irq = ahc->platform_data->irq;
	host->max_id = (ahc->features & AHC_WIDE) ? 16 : 8;
	host->max_lun = AHC_NUM_LUNS;
	host->max_channel = (ahc->features & AHC_TWIN) ? 1 : 0;
	host->sg_tablesize = AHC_NSEG;
	ahc_lock(ahc, &s);
	ahc_set_unit(ahc, ahc_linux_unit++);
	ahc_unlock(ahc, &s);
	sprintf(buf, "scsi%d", host->host_no);
	new_name = malloc(strlen(buf) + 1, M_DEVBUF, M_NOWAIT);
	if (new_name != NULL) {
		strcpy(new_name, buf);
		ahc_set_name(ahc, new_name);
	}
	host->unique_id = ahc->unit;
	ahc_linux_initialize_scsi_bus(ahc);
	ahc_intr_enable(ahc, TRUE);

	host->transportt = ahc_linux_transport_template;

	retval = scsi_add_host(host,
			(ahc->dev_softc ? &ahc->dev_softc->dev : NULL));
	if (retval) {
		printk(KERN_WARNING "aic7xxx: scsi_add_host failed\n");
		scsi_host_put(host);
		return retval;
	}

	scsi_scan_host(host);
	return 0;
}

/*
 * Place the SCSI bus into a known state by either resetting it,
 * or forcing transfer negotiations on the next command to any
 * target.
 */
void
ahc_linux_initialize_scsi_bus(struct ahc_softc *ahc)
{
	int i;
	int numtarg;
	unsigned long s;

	i = 0;
	numtarg = 0;

	ahc_lock(ahc, &s);

	if (aic7xxx_no_reset != 0)
		ahc->flags &= ~(AHC_RESET_BUS_A|AHC_RESET_BUS_B);

	if ((ahc->flags & AHC_RESET_BUS_A) != 0)
		ahc_reset_channel(ahc, 'A', /*initiate_reset*/TRUE);
	else
		numtarg = (ahc->features & AHC_WIDE) ? 16 : 8;

	if ((ahc->features & AHC_TWIN) != 0) {

		if ((ahc->flags & AHC_RESET_BUS_B) != 0) {
			ahc_reset_channel(ahc, 'B', /*initiate_reset*/TRUE);
		} else {
			if (numtarg == 0)
				i = 8;
			numtarg += 8;
		}
	}

	/*
	 * Force negotiation to async for all targets that
	 * will not see an initial bus reset.
	 */
	for (; i < numtarg; i++) {
		struct ahc_devinfo devinfo;
		struct ahc_initiator_tinfo *tinfo;
		struct ahc_tmode_tstate *tstate;
		u_int our_id;
		u_int target_id;
		char channel;

		channel = 'A';
		our_id = ahc->our_id;
		target_id = i;
		if (i > 7 && (ahc->features & AHC_TWIN) != 0) {
			channel = 'B';
			our_id = ahc->our_id_b;
			target_id = i % 8;
		}
		tinfo = ahc_fetch_transinfo(ahc, channel, our_id,
					    target_id, &tstate);
		ahc_compile_devinfo(&devinfo, our_id, target_id,
				    CAM_LUN_WILDCARD, channel, ROLE_INITIATOR);
		ahc_update_neg_request(ahc, &devinfo, tstate,
				       tinfo, AHC_NEG_ALWAYS);
	}
	ahc_unlock(ahc, &s);
	/* Give the bus some time to recover */
	if ((ahc->flags & (AHC_RESET_BUS_A|AHC_RESET_BUS_B)) != 0) {
		ahc_linux_freeze_simq(ahc);
		msleep(AIC7XXX_RESET_DELAY);
		ahc_linux_release_simq(ahc);
	}
}

int
ahc_platform_alloc(struct ahc_softc *ahc, void *platform_arg)
{

	ahc->platform_data =
	    malloc(sizeof(struct ahc_platform_data), M_DEVBUF, M_NOWAIT);
	if (ahc->platform_data == NULL)
		return (ENOMEM);
	memset(ahc->platform_data, 0, sizeof(struct ahc_platform_data));
	ahc->platform_data->irq = AHC_LINUX_NOIRQ;
	ahc_lockinit(ahc);
	ahc->seltime = (aic7xxx_seltime & 0x3) << 4;
	ahc->seltime_b = (aic7xxx_seltime & 0x3) << 4;
	if (aic7xxx_pci_parity == 0)
		ahc->flags |= AHC_DISABLE_PCI_PERR;

	return (0);
}

void
ahc_platform_free(struct ahc_softc *ahc)
{
	struct scsi_target *starget;
	int i;

	if (ahc->platform_data != NULL) {
		/* destroy all of the device and target objects */
		for (i = 0; i < AHC_NUM_TARGETS; i++) {
			starget = ahc->platform_data->starget[i];
			if (starget != NULL) {
				ahc->platform_data->starget[i] = NULL;
 			}
 		}

		if (ahc->platform_data->irq != AHC_LINUX_NOIRQ)
			free_irq(ahc->platform_data->irq, ahc);
		if (ahc->tag == BUS_SPACE_PIO
		 && ahc->bsh.ioport != 0)
			release_region(ahc->bsh.ioport, 256);
		if (ahc->tag == BUS_SPACE_MEMIO
		 && ahc->bsh.maddr != NULL) {
			iounmap(ahc->bsh.maddr);
			release_mem_region(ahc->platform_data->mem_busaddr,
					   0x1000);
		}

		if (ahc->platform_data->host)
			scsi_host_put(ahc->platform_data->host);

		free(ahc->platform_data, M_DEVBUF);
	}
}

void
ahc_platform_freeze_devq(struct ahc_softc *ahc, struct scb *scb)
{
	ahc_platform_abort_scbs(ahc, SCB_GET_TARGET(ahc, scb),
				SCB_GET_CHANNEL(ahc, scb),
				SCB_GET_LUN(scb), SCB_LIST_NULL,
				ROLE_UNKNOWN, CAM_REQUEUE_REQ);
}

void
ahc_platform_set_tags(struct ahc_softc *ahc, struct scsi_device *sdev,
		      struct ahc_devinfo *devinfo, ahc_queue_alg alg)
{
	struct ahc_linux_device *dev;
	int was_queuing;
	int now_queuing;

	if (sdev == NULL)
		return;
	dev = scsi_transport_device_data(sdev);

	was_queuing = dev->flags & (AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED);
	switch (alg) {
	default:
	case AHC_QUEUE_NONE:
		now_queuing = 0;
		break; 
	case AHC_QUEUE_BASIC:
		now_queuing = AHC_DEV_Q_BASIC;
		break;
	case AHC_QUEUE_TAGGED:
		now_queuing = AHC_DEV_Q_TAGGED;
		break;
	}
	if ((dev->flags & AHC_DEV_FREEZE_TIL_EMPTY) == 0
	 && (was_queuing != now_queuing)
	 && (dev->active != 0)) {
		dev->flags |= AHC_DEV_FREEZE_TIL_EMPTY;
		dev->qfrozen++;
	}

	dev->flags &= ~(AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED|AHC_DEV_PERIODIC_OTAG);
	if (now_queuing) {
		u_int usertags;

		usertags = ahc_linux_user_tagdepth(ahc, devinfo);
		if (!was_queuing) {
			/*
			 * Start out agressively and allow our
			 * dynamic queue depth algorithm to take
			 * care of the rest.
			 */
			dev->maxtags = usertags;
			dev->openings = dev->maxtags - dev->active;
		}
		if (dev->maxtags == 0) {
			/*
			 * Queueing is disabled by the user.
			 */
			dev->openings = 1;
		} else if (alg == AHC_QUEUE_TAGGED) {
			dev->flags |= AHC_DEV_Q_TAGGED;
			if (aic7xxx_periodic_otag != 0)
				dev->flags |= AHC_DEV_PERIODIC_OTAG;
		} else
			dev->flags |= AHC_DEV_Q_BASIC;
	} else {
		/* We can only have one opening. */
		dev->maxtags = 0;
		dev->openings =  1 - dev->active;
	}
	switch ((dev->flags & (AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED))) {
	case AHC_DEV_Q_BASIC:
		scsi_set_tag_type(sdev, MSG_SIMPLE_TAG);
		scsi_activate_tcq(sdev, dev->openings + dev->active);
		break;
	case AHC_DEV_Q_TAGGED:
		scsi_set_tag_type(sdev, MSG_ORDERED_TAG);
		scsi_activate_tcq(sdev, dev->openings + dev->active);
		break;
	default:
		/*
		 * We allow the OS to queue 2 untagged transactions to
		 * us at any time even though we can only execute them
		 * serially on the controller/device.  This should
		 * remove some latency.
		 */
		scsi_deactivate_tcq(sdev, 2);
		break;
	}
}

int
ahc_platform_abort_scbs(struct ahc_softc *ahc, int target, char channel,
			int lun, u_int tag, role_t role, uint32_t status)
{
	return 0;
}

static u_int
ahc_linux_user_tagdepth(struct ahc_softc *ahc, struct ahc_devinfo *devinfo)
{
	static int warned_user;
	u_int tags;

	tags = 0;
	if ((ahc->user_discenable & devinfo->target_mask) != 0) {
		if (ahc->unit >= ARRAY_SIZE(aic7xxx_tag_info)) {
			if (warned_user == 0) {

				printf(KERN_WARNING
"aic7xxx: WARNING: Insufficient tag_info instances\n"
"aic7xxx: for installed controllers. Using defaults\n"
"aic7xxx: Please update the aic7xxx_tag_info array in\n"
"aic7xxx: the aic7xxx_osm..c source file.\n");
				warned_user++;
			}
			tags = AHC_MAX_QUEUE;
		} else {
			adapter_tag_info_t *tag_info;

			tag_info = &aic7xxx_tag_info[ahc->unit];
			tags = tag_info->tag_commands[devinfo->target_offset];
			if (tags > AHC_MAX_QUEUE)
				tags = AHC_MAX_QUEUE;
		}
	}
	return (tags);
}

/*
 * Determines the queue depth for a given device.
 */
static void
ahc_linux_device_queue_depth(struct scsi_device *sdev)
{
	struct	ahc_devinfo devinfo;
	u_int	tags;
	struct ahc_softc *ahc = *((struct ahc_softc **)sdev->host->hostdata);

	ahc_compile_devinfo(&devinfo,
			    sdev->sdev_target->channel == 0
			  ? ahc->our_id : ahc->our_id_b,
			    sdev->sdev_target->id, sdev->lun,
			    sdev->sdev_target->channel == 0 ? 'A' : 'B',
			    ROLE_INITIATOR);
	tags = ahc_linux_user_tagdepth(ahc, &devinfo);
	if (tags != 0 && sdev->tagged_supported != 0) {

		ahc_platform_set_tags(ahc, sdev, &devinfo, AHC_QUEUE_TAGGED);
		ahc_send_async(ahc, devinfo.channel, devinfo.target,
			       devinfo.lun, AC_TRANSFER_NEG);
		ahc_print_devinfo(ahc, &devinfo);
		printf("Tagged Queuing enabled.  Depth %d\n", tags);
	} else {
		ahc_platform_set_tags(ahc, sdev, &devinfo, AHC_QUEUE_NONE);
		ahc_send_async(ahc, devinfo.channel, devinfo.target,
			       devinfo.lun, AC_TRANSFER_NEG);
	}
}

static int
ahc_linux_run_command(struct ahc_softc *ahc, struct ahc_linux_device *dev,
		      struct scsi_cmnd *cmd)
{
	struct	 scb *scb;
	struct	 hardware_scb *hscb;
	struct	 ahc_initiator_tinfo *tinfo;
	struct	 ahc_tmode_tstate *tstate;
	uint16_t mask;
	struct scb_tailq *untagged_q = NULL;
	int nseg;

	/*
	 * Schedule us to run later.  The only reason we are not
	 * running is because the whole controller Q is frozen.
	 */
	if (ahc->platform_data->qfrozen != 0)
		return SCSI_MLQUEUE_HOST_BUSY;

	/*
	 * We only allow one untagged transaction
	 * per target in the initiator role unless
	 * we are storing a full busy target *lun*
	 * table in SCB space.
	 */
	if (!blk_rq_tagged(cmd->request)
	    && (ahc->features & AHC_SCB_BTT) == 0) {
		int target_offset;

		target_offset = cmd->device->id + cmd->device->channel * 8;
		untagged_q = &(ahc->untagged_queues[target_offset]);
		if (!TAILQ_EMPTY(untagged_q))
			/* if we're already executing an untagged command
			 * we're busy to another */
			return SCSI_MLQUEUE_DEVICE_BUSY;
	}

	/*
	 * Get an scb to use.
	 */
	scb = ahc_get_scb(ahc);
	if (!scb)
		return SCSI_MLQUEUE_HOST_BUSY;

	scb->io_ctx = cmd;
	scb->platform_data->dev = dev;
	hscb = scb->hscb;
	cmd->host_scribble = (char *)scb;

	/*
	 * Fill out basics of the HSCB.
	 */
	hscb->control = 0;
	hscb->scsiid = BUILD_SCSIID(ahc, cmd);
	hscb->lun = cmd->device->lun;
	mask = SCB_GET_TARGET_MASK(ahc, scb);
	tinfo = ahc_fetch_transinfo(ahc, SCB_GET_CHANNEL(ahc, scb),
				    SCB_GET_OUR_ID(scb),
				    SCB_GET_TARGET(ahc, scb), &tstate);
	hscb->scsirate = tinfo->scsirate;
	hscb->scsioffset = tinfo->curr.offset;
	if ((tstate->ultraenb & mask) != 0)
		hscb->control |= ULTRAENB;
	
	if ((ahc->user_discenable & mask) != 0)
		hscb->control |= DISCENB;
	
	if ((tstate->auto_negotiate & mask) != 0) {
		scb->flags |= SCB_AUTO_NEGOTIATE;
		scb->hscb->control |= MK_MESSAGE;
	}

	if ((dev->flags & (AHC_DEV_Q_TAGGED|AHC_DEV_Q_BASIC)) != 0) {
		int	msg_bytes;
		uint8_t tag_msgs[2];
		
		msg_bytes = scsi_populate_tag_msg(cmd, tag_msgs);
		if (msg_bytes && tag_msgs[0] != MSG_SIMPLE_TASK) {
			hscb->control |= tag_msgs[0];
			if (tag_msgs[0] == MSG_ORDERED_TASK)
				dev->commands_since_idle_or_otag = 0;
		} else if (dev->commands_since_idle_or_otag == AHC_OTAG_THRESH
				&& (dev->flags & AHC_DEV_Q_TAGGED) != 0) {
			hscb->control |= MSG_ORDERED_TASK;
			dev->commands_since_idle_or_otag = 0;
		} else {
			hscb->control |= MSG_SIMPLE_TASK;
		}
	}

	hscb->cdb_len = cmd->cmd_len;
	if (hscb->cdb_len <= 12) {
		memcpy(hscb->shared_data.cdb, cmd->cmnd, hscb->cdb_len);
	} else {
		memcpy(hscb->cdb32, cmd->cmnd, hscb->cdb_len);
		scb->flags |= SCB_CDB32_PTR;
	}

	scb->platform_data->xfer_len = 0;
	ahc_set_residual(scb, 0);
	ahc_set_sense_residual(scb, 0);
	scb->sg_count = 0;

	nseg = scsi_dma_map(cmd);
	BUG_ON(nseg < 0);
	if (nseg > 0) {
		struct	ahc_dma_seg *sg;
		struct	scatterlist *cur_seg;
		int i;

		/* Copy the segments into the SG list. */
		sg = scb->sg_list;
		/*
		 * The sg_count may be larger than nseg if
		 * a transfer crosses a 32bit page.
		 */
		scsi_for_each_sg(cmd, cur_seg, nseg, i) {
			dma_addr_t addr;
			bus_size_t len;
			int consumed;

			addr = sg_dma_address(cur_seg);
			len = sg_dma_len(cur_seg);
			consumed = ahc_linux_map_seg(ahc, scb,
						     sg, addr, len);
			sg += consumed;
			scb->sg_count += consumed;
		}
		sg--;
		sg->len |= ahc_htole32(AHC_DMA_LAST_SEG);

		/*
		 * Reset the sg list pointer.
		 */
		scb->hscb->sgptr =
			ahc_htole32(scb->sg_list_phys | SG_FULL_RESID);
		
		/*
		 * Copy the first SG into the "current"
		 * data pointer area.
		 */
		scb->hscb->dataptr = scb->sg_list->addr;
		scb->hscb->datacnt = scb->sg_list->len;
	} else {
		scb->hscb->sgptr = ahc_htole32(SG_LIST_NULL);
		scb->hscb->dataptr = 0;
		scb->hscb->datacnt = 0;
		scb->sg_count = 0;
	}

	LIST_INSERT_HEAD(&ahc->pending_scbs, scb, pending_links);
	dev->openings--;
	dev->active++;
	dev->commands_issued++;
	if ((dev->flags & AHC_DEV_PERIODIC_OTAG) != 0)
		dev->commands_since_idle_or_otag++;
	
	scb->flags |= SCB_ACTIVE;
	if (untagged_q) {
		TAILQ_INSERT_TAIL(untagged_q, scb, links.tqe);
		scb->flags |= SCB_UNTAGGEDQ;
	}
	ahc_queue_scb(ahc, scb);
	return 0;
}

/*
 * SCSI controller interrupt handler.
 */
irqreturn_t
ahc_linux_isr(int irq, void *dev_id)
{
	struct	ahc_softc *ahc;
	u_long	flags;
	int	ours;

	ahc = (struct ahc_softc *) dev_id;
	ahc_lock(ahc, &flags); 
	ours = ahc_intr(ahc);
	ahc_unlock(ahc, &flags);
	return IRQ_RETVAL(ours);
}

void
ahc_platform_flushwork(struct ahc_softc *ahc)
{

}

void
ahc_send_async(struct ahc_softc *ahc, char channel,
	       u_int target, u_int lun, ac_code code)
{
	switch (code) {
	case AC_TRANSFER_NEG:
	{
		char	buf[80];
		struct	scsi_target *starget;
		struct	ahc_linux_target *targ;
		struct	info_str info;
		struct	ahc_initiator_tinfo *tinfo;
		struct	ahc_tmode_tstate *tstate;
		int	target_offset;
		unsigned int target_ppr_options;

		BUG_ON(target == CAM_TARGET_WILDCARD);

		info.buffer = buf;
		info.length = sizeof(buf);
		info.offset = 0;
		info.pos = 0;
		tinfo = ahc_fetch_transinfo(ahc, channel,
						channel == 'A' ? ahc->our_id
							       : ahc->our_id_b,
						target, &tstate);

		/*
		 * Don't bother reporting results while
		 * negotiations are still pending.
		 */
		if (tinfo->curr.period != tinfo->goal.period
		 || tinfo->curr.width != tinfo->goal.width
		 || tinfo->curr.offset != tinfo->goal.offset
		 || tinfo->curr.ppr_options != tinfo->goal.ppr_options)
			if (bootverbose == 0)
				break;

		/*
		 * Don't bother reporting results that
		 * are identical to those last reported.
		 */
		target_offset = target;
		if (channel == 'B')
			target_offset += 8;
		starget = ahc->platform_data->starget[target_offset];
		if (starget == NULL)
			break;
		targ = scsi_transport_target_data(starget);

		target_ppr_options =
			(spi_dt(starget) ? MSG_EXT_PPR_DT_REQ : 0)
			+ (spi_qas(starget) ? MSG_EXT_PPR_QAS_REQ : 0)
			+ (spi_iu(starget) ?  MSG_EXT_PPR_IU_REQ : 0);

		if (tinfo->curr.period == spi_period(starget)
		    && tinfo->curr.width == spi_width(starget)
		    && tinfo->curr.offset == spi_offset(starget)
		 && tinfo->curr.ppr_options == target_ppr_options)
			if (bootverbose == 0)
				break;

		spi_period(starget) = tinfo->curr.period;
		spi_width(starget) = tinfo->curr.width;
		spi_offset(starget) = tinfo->curr.offset;
		spi_dt(starget) = tinfo->curr.ppr_options & MSG_EXT_PPR_DT_REQ ? 1 : 0;
		spi_qas(starget) = tinfo->curr.ppr_options & MSG_EXT_PPR_QAS_REQ ? 1 : 0;
		spi_iu(starget) = tinfo->curr.ppr_options & MSG_EXT_PPR_IU_REQ ? 1 : 0;
		spi_display_xfer_agreement(starget);
		break;
	}
        case AC_SENT_BDR:
	{
		WARN_ON(lun != CAM_LUN_WILDCARD);
		scsi_report_device_reset(ahc->platform_data->host,
					 channel - 'A', target);
		break;
	}
        case AC_BUS_RESET:
		if (ahc->platform_data->host != NULL) {
			scsi_report_bus_reset(ahc->platform_data->host,
					      channel - 'A');
		}
                break;
        default:
                panic("ahc_send_async: Unexpected async event");
        }
}

/*
 * Calls the higher level scsi done function and frees the scb.
 */
void
ahc_done(struct ahc_softc *ahc, struct scb *scb)
{
	struct scsi_cmnd *cmd;
	struct	   ahc_linux_device *dev;

	LIST_REMOVE(scb, pending_links);
	if ((scb->flags & SCB_UNTAGGEDQ) != 0) {
		struct scb_tailq *untagged_q;
		int target_offset;

		target_offset = SCB_GET_TARGET_OFFSET(ahc, scb);
		untagged_q = &(ahc->untagged_queues[target_offset]);
		TAILQ_REMOVE(untagged_q, scb, links.tqe);
		BUG_ON(!TAILQ_EMPTY(untagged_q));
	}

	if ((scb->flags & SCB_ACTIVE) == 0) {
		printf("SCB %d done'd twice\n", scb->hscb->tag);
		ahc_dump_card_state(ahc);
		panic("Stopping for safety");
	}
	cmd = scb->io_ctx;
	dev = scb->platform_data->dev;
	dev->active--;
	dev->openings++;
	if ((cmd->result & (CAM_DEV_QFRZN << 16)) != 0) {
		cmd->result &= ~(CAM_DEV_QFRZN << 16);
		dev->qfrozen--;
	}
	ahc_linux_unmap_scb(ahc, scb);

	/*
	 * Guard against stale sense data.
	 * The Linux mid-layer assumes that sense
	 * was retrieved anytime the first byte of
	 * the sense buffer looks "sane".
	 */
	cmd->sense_buffer[0] = 0;
	if (ahc_get_transaction_status(scb) == CAM_REQ_INPROG) {
		uint32_t amount_xferred;

		amount_xferred =
		    ahc_get_transfer_length(scb) - ahc_get_residual(scb);
		if ((scb->flags & SCB_TRANSMISSION_ERROR) != 0) {
#ifdef AHC_DEBUG
			if ((ahc_debug & AHC_SHOW_MISC) != 0) {
				ahc_print_path(ahc, scb);
				printf("Set CAM_UNCOR_PARITY\n");
			}
#endif
			ahc_set_transaction_status(scb, CAM_UNCOR_PARITY);
#ifdef AHC_REPORT_UNDERFLOWS
		/*
		 * This code is disabled by default as some
		 * clients of the SCSI system do not properly
		 * initialize the underflow parameter.  This
		 * results in spurious termination of commands
		 * that complete as expected (e.g. underflow is
		 * allowed as command can return variable amounts
		 * of data.
		 */
		} else if (amount_xferred < scb->io_ctx->underflow) {
			u_int i;

			ahc_print_path(ahc, scb);
			printf("CDB:");
			for (i = 0; i < scb->io_ctx->cmd_len; i++)
				printf(" 0x%x", scb->io_ctx->cmnd[i]);
			printf("\n");
			ahc_print_path(ahc, scb);
			printf("Saw underflow (%ld of %ld bytes). "
			       "Treated as error\n",
				ahc_get_residual(scb),
				ahc_get_transfer_length(scb));
			ahc_set_transaction_status(scb, CAM_DATA_RUN_ERR);
#endif
		} else {
			ahc_set_transaction_status(scb, CAM_REQ_CMP);
		}
	} else if (ahc_get_transaction_status(scb) == CAM_SCSI_STATUS_ERROR) {
		ahc_linux_handle_scsi_status(ahc, cmd->device, scb);
	}

	if (dev->openings == 1
	 && ahc_get_transaction_status(scb) == CAM_REQ_CMP
	 && ahc_get_scsi_status(scb) != SCSI_STATUS_QUEUE_FULL)
		dev->tag_success_count++;
	/*
	 * Some devices deal with temporary internal resource
	 * shortages by returning queue full.  When the queue
	 * full occurrs, we throttle back.  Slowly try to get
	 * back to our previous queue depth.
	 */
	if ((dev->openings + dev->active) < dev->maxtags
	 && dev->tag_success_count > AHC_TAG_SUCCESS_INTERVAL) {
		dev->tag_success_count = 0;
		dev->openings++;
	}

	if (dev->active == 0)
		dev->commands_since_idle_or_otag = 0;

	if ((scb->flags & SCB_RECOVERY_SCB) != 0) {
		printf("Recovery SCB completes\n");
		if (ahc_get_transaction_status(scb) == CAM_BDR_SENT
		 || ahc_get_transaction_status(scb) == CAM_REQ_ABORTED)
			ahc_set_transaction_status(scb, CAM_CMD_TIMEOUT);

		if (ahc->platform_data->eh_done)
			complete(ahc->platform_data->eh_done);
	}

	ahc_free_scb(ahc, scb);
	ahc_linux_queue_cmd_complete(ahc, cmd);
}

static void
ahc_linux_handle_scsi_status(struct ahc_softc *ahc,
			     struct scsi_device *sdev, struct scb *scb)
{
	struct	ahc_devinfo devinfo;
	struct ahc_linux_device *dev = scsi_transport_device_data(sdev);

	ahc_compile_devinfo(&devinfo,
			    ahc->our_id,
			    sdev->sdev_target->id, sdev->lun,
			    sdev->sdev_target->channel == 0 ? 'A' : 'B',
			    ROLE_INITIATOR);
	
	/*
	 * We don't currently trust the mid-layer to
	 * properly deal with queue full or busy.  So,
	 * when one occurs, we tell the mid-layer to
	 * unconditionally requeue the command to us
	 * so that we can retry it ourselves.  We also
	 * implement our own throttling mechanism so
	 * we don't clobber the device with too many
	 * commands.
	 */
	switch (ahc_get_scsi_status(scb)) {
	default:
		break;
	case SCSI_STATUS_CHECK_COND:
	case SCSI_STATUS_CMD_TERMINATED:
	{
		struct scsi_cmnd *cmd;

		/*
		 * Copy sense information to the OS's cmd
		 * structure if it is available.
		 */
		cmd = scb->io_ctx;
		if (scb->flags & SCB_SENSE) {
			u_int sense_size;

			sense_size = min(sizeof(struct scsi_sense_data)
				       - ahc_get_sense_residual(scb),
					 (u_long)sizeof(cmd->sense_buffer));
			memcpy(cmd->sense_buffer,
			       ahc_get_sense_buf(ahc, scb), sense_size);
			if (sense_size < sizeof(cmd->sense_buffer))
				memset(&cmd->sense_buffer[sense_size], 0,
				       sizeof(cmd->sense_buffer) - sense_size);
			cmd->result |= (DRIVER_SENSE << 24);
#ifdef AHC_DEBUG
			if (ahc_debug & AHC_SHOW_SENSE) {
				int i;

				printf("Copied %d bytes of sense data:",
				       sense_size);
				for (i = 0; i < sense_size; i++) {
					if ((i & 0xF) == 0)
						printf("\n");
					printf("0x%x ", cmd->sense_buffer[i]);
				}
				printf("\n");
			}
#endif
		}
		break;
	}
	case SCSI_STATUS_QUEUE_FULL:
	{
		/*
		 * By the time the core driver has returned this
		 * command, all other commands that were queued
		 * to us but not the device have been returned.
		 * This ensures that dev->active is equal to
		 * the number of commands actually queued to
		 * the device.
		 */
		dev->tag_success_count = 0;
		if (dev->active != 0) {
			/*
			 * Drop our opening count to the number
			 * of commands currently outstanding.
			 */
			dev->openings = 0;
/*
			ahc_print_path(ahc, scb);
			printf("Dropping tag count to %d\n", dev->active);
 */
			if (dev->active == dev->tags_on_last_queuefull) {

				dev->last_queuefull_same_count++;
				/*
				 * If we repeatedly see a queue full
				 * at the same queue depth, this
				 * device has a fixed number of tag
				 * slots.  Lock in this tag depth
				 * so we stop seeing queue fulls from
				 * this device.
				 */
				if (dev->last_queuefull_same_count
				 == AHC_LOCK_TAGS_COUNT) {
					dev->maxtags = dev->active;
					ahc_print_path(ahc, scb);
					printf("Locking max tag count at %d\n",
					       dev->active);
				}
			} else {
				dev->tags_on_last_queuefull = dev->active;
				dev->last_queuefull_same_count = 0;
			}
			ahc_set_transaction_status(scb, CAM_REQUEUE_REQ);
			ahc_set_scsi_status(scb, SCSI_STATUS_OK);
			ahc_platform_set_tags(ahc, sdev, &devinfo,
				     (dev->flags & AHC_DEV_Q_BASIC)
				   ? AHC_QUEUE_BASIC : AHC_QUEUE_TAGGED);
			break;
		}
		/*
		 * Drop down to a single opening, and treat this
		 * as if the target returned BUSY SCSI status.
		 */
		dev->openings = 1;
		ahc_set_scsi_status(scb, SCSI_STATUS_BUSY);
		ahc_platform_set_tags(ahc, sdev, &devinfo,
			     (dev->flags & AHC_DEV_Q_BASIC)
			   ? AHC_QUEUE_BASIC : AHC_QUEUE_TAGGED);
		break;
	}
	}
}

static void
ahc_linux_queue_cmd_complete(struct ahc_softc *ahc, struct scsi_cmnd *cmd)
{
	/*
	 * Map CAM error codes into Linux Error codes.  We
	 * avoid the conversion so that the DV code has the
	 * full error information available when making
	 * state change decisions.
	 */
	{
		u_int new_status;

		switch (ahc_cmd_get_transaction_status(cmd)) {
		case CAM_REQ_INPROG:
		case CAM_REQ_CMP:
		case CAM_SCSI_STATUS_ERROR:
			new_status = DID_OK;
			break;
		case CAM_REQ_ABORTED:
			new_status = DID_ABORT;
			break;
		case CAM_BUSY:
			new_status = DID_BUS_BUSY;
			break;
		case CAM_REQ_INVALID:
		case CAM_PATH_INVALID:
			new_status = DID_BAD_TARGET;
			break;
		case CAM_SEL_TIMEOUT:
			new_status = DID_NO_CONNECT;
			break;
		case CAM_SCSI_BUS_RESET:
		case CAM_BDR_SENT:
			new_status = DID_RESET;
			break;
		case CAM_UNCOR_PARITY:
			new_status = DID_PARITY;
			break;
		case CAM_CMD_TIMEOUT:
			new_status = DID_TIME_OUT;
			break;
		case CAM_UA_ABORT:
		case CAM_REQ_CMP_ERR:
		case CAM_AUTOSENSE_FAIL:
		case CAM_NO_HBA:
		case CAM_DATA_RUN_ERR:
		case CAM_UNEXP_BUSFREE:
		case CAM_SEQUENCE_FAIL:
		case CAM_CCB_LEN_ERR:
		case CAM_PROVIDE_FAIL:
		case CAM_REQ_TERMIO:
		case CAM_UNREC_HBA_ERROR:
		case CAM_REQ_TOO_BIG:
			new_status = DID_ERROR;
			break;
		case CAM_REQUEUE_REQ:
			new_status = DID_REQUEUE;
			break;
		default:
			/* We should never get here */
			new_status = DID_ERROR;
			break;
		}

		ahc_cmd_set_transaction_status(cmd, new_status);
	}

	cmd->scsi_done(cmd);
}

static void
ahc_linux_freeze_simq(struct ahc_softc *ahc)
{
	unsigned long s;

	ahc_lock(ahc, &s);
	ahc->platform_data->qfrozen++;
	if (ahc->platform_data->qfrozen == 1) {
		scsi_block_requests(ahc->platform_data->host);

		/* XXX What about Twin channels? */
		ahc_platform_abort_scbs(ahc, CAM_TARGET_WILDCARD, ALL_CHANNELS,
					CAM_LUN_WILDCARD, SCB_LIST_NULL,
					ROLE_INITIATOR, CAM_REQUEUE_REQ);
	}
	ahc_unlock(ahc, &s);
}

static void
ahc_linux_release_simq(struct ahc_softc *ahc)
{
	u_long s;
	int    unblock_reqs;

	unblock_reqs = 0;
	ahc_lock(ahc, &s);
	if (ahc->platform_data->qfrozen > 0)
		ahc->platform_data->qfrozen--;
	if (ahc->platform_data->qfrozen == 0)
		unblock_reqs = 1;
	ahc_unlock(ahc, &s);
	/*
	 * There is still a race here.  The mid-layer
	 * should keep its own freeze count and use
	 * a bottom half handler to run the queues
	 * so we can unblock with our own lock held.
	 */
	if (unblock_reqs)
		scsi_unblock_requests(ahc->platform_data->host);
}

static int
ahc_linux_queue_recovery_cmd(struct scsi_cmnd *cmd, scb_flag flag)
{
	struct ahc_softc *ahc;
	struct ahc_linux_device *dev;
	struct scb *pending_scb;
	u_int  saved_scbptr;
	u_int  active_scb_index;
	u_int  last_phase;
	u_int  saved_scsiid;
	u_int  cdb_byte;
	int    retval;
	int    was_paused;
	int    paused;
	int    wait;
	int    disconnected;
	unsigned long flags;

	pending_scb = NULL;
	paused = FALSE;
	wait = FALSE;
	ahc = *(struct ahc_softc **)cmd->device->host->hostdata;

	scmd_printk(KERN_INFO, cmd, "Attempting to queue a%s message\n",
	       flag == SCB_ABORT ? "n ABORT" : " TARGET RESET");

	printf("CDB:");
	for (cdb_byte = 0; cdb_byte < cmd->cmd_len; cdb_byte++)
		printf(" 0x%x", cmd->cmnd[cdb_byte]);
	printf("\n");

	ahc_lock(ahc, &flags);

	/*
	 * First determine if we currently own this command.
	 * Start by searching the device queue.  If not found
	 * there, check the pending_scb list.  If not found
	 * at all, and the system wanted us to just abort the
	 * command, return success.
	 */
	dev = scsi_transport_device_data(cmd->device);

	if (dev == NULL) {
		/*
		 * No target device for this command exists,
		 * so we must not still own the command.
		 */
		printf("%s:%d:%d:%d: Is not an active device\n",
		       ahc_name(ahc), cmd->device->channel, cmd->device->id,
		       cmd->device->lun);
		retval = SUCCESS;
		goto no_cmd;
	}

	if ((dev->flags & (AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED)) == 0
	 && ahc_search_untagged_queues(ahc, cmd, cmd->device->id,
				       cmd->device->channel + 'A',
				       cmd->device->lun,
				       CAM_REQ_ABORTED, SEARCH_COMPLETE) != 0) {
		printf("%s:%d:%d:%d: Command found on untagged queue\n",
		       ahc_name(ahc), cmd->device->channel, cmd->device->id,
		       cmd->device->lun);
		retval = SUCCESS;
		goto done;
	}

	/*
	 * See if we can find a matching cmd in the pending list.
	 */
	LIST_FOREACH(pending_scb, &ahc->pending_scbs, pending_links) {
		if (pending_scb->io_ctx == cmd)
			break;
	}

	if (pending_scb == NULL && flag == SCB_DEVICE_RESET) {

		/* Any SCB for this device will do for a target reset */
		LIST_FOREACH(pending_scb, &ahc->pending_scbs, pending_links) {
		  	if (ahc_match_scb(ahc, pending_scb, scmd_id(cmd),
					  scmd_channel(cmd) + 'A',
					  CAM_LUN_WILDCARD,
					  SCB_LIST_NULL, ROLE_INITIATOR))
				break;
		}
	}

	if (pending_scb == NULL) {
		scmd_printk(KERN_INFO, cmd, "Command not found\n");
		goto no_cmd;
	}

	if ((pending_scb->flags & SCB_RECOVERY_SCB) != 0) {
		/*
		 * We can't queue two recovery actions using the same SCB
		 */
		retval = FAILED;
		goto  done;
	}

	/*
	 * Ensure that the card doesn't do anything
	 * behind our back and that we didn't "just" miss
	 * an interrupt that would affect this cmd.
	 */
	was_paused = ahc_is_paused(ahc);
	ahc_pause_and_flushwork(ahc);
	paused = TRUE;

	if ((pending_scb->flags & SCB_ACTIVE) == 0) {
		scmd_printk(KERN_INFO, cmd, "Command already completed\n");
		goto no_cmd;
	}

	printf("%s: At time of recovery, card was %spaused\n",
	       ahc_name(ahc), was_paused ? "" : "not ");
	ahc_dump_card_state(ahc);

	disconnected = TRUE;
	if (flag == SCB_ABORT) {
		if (ahc_search_qinfifo(ahc, cmd->device->id,
				       cmd->device->channel + 'A',
				       cmd->device->lun,
				       pending_scb->hscb->tag,
				       ROLE_INITIATOR, CAM_REQ_ABORTED,
				       SEARCH_COMPLETE) > 0) {
			printf("%s:%d:%d:%d: Cmd aborted from QINFIFO\n",
			       ahc_name(ahc), cmd->device->channel,
					cmd->device->id, cmd->device->lun);
			retval = SUCCESS;
			goto done;
		}
	} else if (ahc_search_qinfifo(ahc, cmd->device->id,
				      cmd->device->channel + 'A',
				      cmd->device->lun, pending_scb->hscb->tag,
				      ROLE_INITIATOR, /*status*/0,
				      SEARCH_COUNT) > 0) {
		disconnected = FALSE;
	}

	if (disconnected && (ahc_inb(ahc, SEQ_FLAGS) & NOT_IDENTIFIED) == 0) {
		struct scb *bus_scb;

		bus_scb = ahc_lookup_scb(ahc, ahc_inb(ahc, SCB_TAG));
		if (bus_scb == pending_scb)
			disconnected = FALSE;
		else if (flag != SCB_ABORT
		      && ahc_inb(ahc, SAVED_SCSIID) == pending_scb->hscb->scsiid
		      && ahc_inb(ahc, SAVED_LUN) == SCB_GET_LUN(pending_scb))
			disconnected = FALSE;
	}

	/*
	 * At this point, pending_scb is the scb associated with the
	 * passed in command.  That command is currently active on the
	 * bus, is in the disconnected state, or we're hoping to find
	 * a command for the same target active on the bus to abuse to
	 * send a BDR.  Queue the appropriate message based on which of
	 * these states we are in.
	 */
	last_phase = ahc_inb(ahc, LASTPHASE);
	saved_scbptr = ahc_inb(ahc, SCBPTR);
	active_scb_index = ahc_inb(ahc, SCB_TAG);
	saved_scsiid = ahc_inb(ahc, SAVED_SCSIID);
	if (last_phase != P_BUSFREE
	 && (pending_scb->hscb->tag == active_scb_index
	  || (flag == SCB_DEVICE_RESET
	   && SCSIID_TARGET(ahc, saved_scsiid) == scmd_id(cmd)))) {

		/*
		 * We're active on the bus, so assert ATN
		 * and hope that the target responds.
		 */
		pending_scb = ahc_lookup_scb(ahc, active_scb_index);
		pending_scb->flags |= SCB_RECOVERY_SCB|flag;
		ahc_outb(ahc, MSG_OUT, HOST_MSG);
		ahc_outb(ahc, SCSISIGO, last_phase|ATNO);
		scmd_printk(KERN_INFO, cmd, "Device is active, asserting ATN\n");
		wait = TRUE;
	} else if (disconnected) {

		/*
		 * Actually re-queue this SCB in an attempt
		 * to select the device before it reconnects.
		 * In either case (selection or reselection),
		 * we will now issue the approprate message
		 * to the timed-out device.
		 *
		 * Set the MK_MESSAGE control bit indicating
		 * that we desire to send a message.  We
		 * also set the disconnected flag since
		 * in the paging case there is no guarantee
		 * that our SCB control byte matches the
		 * version on the card.  We don't want the
		 * sequencer to abort the command thinking
		 * an unsolicited reselection occurred.
		 */
		pending_scb->hscb->control |= MK_MESSAGE|DISCONNECTED;
		pending_scb->flags |= SCB_RECOVERY_SCB|flag;

		/*
		 * Remove any cached copy of this SCB in the
		 * disconnected list in preparation for the
		 * queuing of our abort SCB.  We use the
		 * same element in the SCB, SCB_NEXT, for
		 * both the qinfifo and the disconnected list.
		 */
		ahc_search_disc_list(ahc, cmd->device->id,
				     cmd->device->channel + 'A',
				     cmd->device->lun, pending_scb->hscb->tag,
				     /*stop_on_first*/TRUE,
				     /*remove*/TRUE,
				     /*save_state*/FALSE);

		/*
		 * In the non-paging case, the sequencer will
		 * never re-reference the in-core SCB.
		 * To make sure we are notified during
		 * reslection, set the MK_MESSAGE flag in
		 * the card's copy of the SCB.
		 */
		if ((ahc->flags & AHC_PAGESCBS) == 0) {
			ahc_outb(ahc, SCBPTR, pending_scb->hscb->tag);
			ahc_outb(ahc, SCB_CONTROL,
				 ahc_inb(ahc, SCB_CONTROL)|MK_MESSAGE);
		}

		/*
		 * Clear out any entries in the QINFIFO first
		 * so we are the next SCB for this target
		 * to run.
		 */
		ahc_search_qinfifo(ahc, cmd->device->id,
				   cmd->device->channel + 'A',
				   cmd->device->lun, SCB_LIST_NULL,
				   ROLE_INITIATOR, CAM_REQUEUE_REQ,
				   SEARCH_COMPLETE);
		ahc_qinfifo_requeue_tail(ahc, pending_scb);
		ahc_outb(ahc, SCBPTR, saved_scbptr);
		ahc_print_path(ahc, pending_scb);
		printf("Device is disconnected, re-queuing SCB\n");
		wait = TRUE;
	} else {
		scmd_printk(KERN_INFO, cmd, "Unable to deliver message\n");
		retval = FAILED;
		goto done;
	}

no_cmd:
	/*
	 * Our assumption is that if we don't have the command, no
	 * recovery action was required, so we return success.  Again,
	 * the semantics of the mid-layer recovery engine are not
	 * well defined, so this may change in time.
	 */
	retval = SUCCESS;
done:
	if (paused)
		ahc_unpause(ahc);
	if (wait) {
		DECLARE_COMPLETION_ONSTACK(done);

		ahc->platform_data->eh_done = &done;
		ahc_unlock(ahc, &flags);

		printf("Recovery code sleeping\n");
		if (!wait_for_completion_timeout(&done, 5 * HZ)) {
			ahc_lock(ahc, &flags);
			ahc->platform_data->eh_done = NULL;
			ahc_unlock(ahc, &flags);

			printf("Timer Expired\n");
			retval = FAILED;
		}
		printf("Recovery code awake\n");
	} else
		ahc_unlock(ahc, &flags);
	return (retval);
}

void
ahc_platform_dump_card_state(struct ahc_softc *ahc)
{
}

static void ahc_linux_set_width(struct scsi_target *starget, int width)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct ahc_softc *ahc = *((struct ahc_softc **)shost->hostdata);
	struct ahc_devinfo devinfo;
	unsigned long flags;

	ahc_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
			    starget->channel + 'A', ROLE_INITIATOR);
	ahc_lock(ahc, &flags);
	ahc_set_width(ahc, &devinfo, width, AHC_TRANS_GOAL, FALSE);
	ahc_unlock(ahc, &flags);
}

static void ahc_linux_set_period(struct scsi_target *starget, int period)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct ahc_softc *ahc = *((struct ahc_softc **)shost->hostdata);
	struct ahc_tmode_tstate *tstate;
	struct ahc_initiator_tinfo *tinfo 
		= ahc_fetch_transinfo(ahc,
				      starget->channel + 'A',
				      shost->this_id, starget->id, &tstate);
	struct ahc_devinfo devinfo;
	unsigned int ppr_options = tinfo->goal.ppr_options;
	unsigned long flags;
	unsigned long offset = tinfo->goal.offset;
	struct ahc_syncrate *syncrate;

	if (offset == 0)
		offset = MAX_OFFSET;

	if (period < 9)
		period = 9;	/* 12.5ns is our minimum */
	if (period == 9) {
		if (spi_max_width(starget))
			ppr_options |= MSG_EXT_PPR_DT_REQ;
		else
			/* need wide for DT and need DT for 12.5 ns */
			period = 10;
	}

	ahc_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
			    starget->channel + 'A', ROLE_INITIATOR);

	/* all PPR requests apart from QAS require wide transfers */
	if (ppr_options & ~MSG_EXT_PPR_QAS_REQ) {
		if (spi_width(starget) == 0)
			ppr_options &= MSG_EXT_PPR_QAS_REQ;
	}

	syncrate = ahc_find_syncrate(ahc, &period, &ppr_options, AHC_SYNCRATE_DT);
	ahc_lock(ahc, &flags);
	ahc_set_syncrate(ahc, &devinfo, syncrate, period, offset,
			 ppr_options, AHC_TRANS_GOAL, FALSE);
	ahc_unlock(ahc, &flags);
}

static void ahc_linux_set_offset(struct scsi_target *starget, int offset)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct ahc_softc *ahc = *((struct ahc_softc **)shost->hostdata);
	struct ahc_tmode_tstate *tstate;
	struct ahc_initiator_tinfo *tinfo 
		= ahc_fetch_transinfo(ahc,
				      starget->channel + 'A',
				      shost->this_id, starget->id, &tstate);
	struct ahc_devinfo devinfo;
	unsigned int ppr_options = 0;
	unsigned int period = 0;
	unsigned long flags;
	struct ahc_syncrate *syncrate = NULL;

	ahc_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
			    starget->channel + 'A', ROLE_INITIATOR);
	if (offset != 0) {
		syncrate = ahc_find_syncrate(ahc, &period, &ppr_options, AHC_SYNCRATE_DT);
		period = tinfo->goal.period;
		ppr_options = tinfo->goal.ppr_options;
	}
	ahc_lock(ahc, &flags);
	ahc_set_syncrate(ahc, &devinfo, syncrate, period, offset,
			 ppr_options, AHC_TRANS_GOAL, FALSE);
	ahc_unlock(ahc, &flags);
}

static void ahc_linux_set_dt(struct scsi_target *starget, int dt)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct ahc_softc *ahc = *((struct ahc_softc **)shost->hostdata);
	struct ahc_tmode_tstate *tstate;
	struct ahc_initiator_tinfo *tinfo 
		= ahc_fetch_transinfo(ahc,
				      starget->channel + 'A',
				      shost->this_id, starget->id, &tstate);
	struct ahc_devinfo devinfo;
	unsigned int ppr_options = tinfo->goal.ppr_options
		& ~MSG_EXT_PPR_DT_REQ;
	unsigned int period = tinfo->goal.period;
	unsigned int width = tinfo->goal.width;
	unsigned long flags;
	struct ahc_syncrate *syncrate;

	if (dt && spi_max_width(starget)) {
		ppr_options |= MSG_EXT_PPR_DT_REQ;
		if (!width)
			ahc_linux_set_width(starget, 1);
	} else if (period == 9)
		period = 10;	/* if resetting DT, period must be >= 25ns */

	ahc_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
			    starget->channel + 'A', ROLE_INITIATOR);
	syncrate = ahc_find_syncrate(ahc, &period, &ppr_options,AHC_SYNCRATE_DT);
	ahc_lock(ahc, &flags);
	ahc_set_syncrate(ahc, &devinfo, syncrate, period, tinfo->goal.offset,
			 ppr_options, AHC_TRANS_GOAL, FALSE);
	ahc_unlock(ahc, &flags);
}

#if 0
/* FIXME: This code claims to support IU and QAS.  However, the actual
 * sequencer code and aic7xxx_core have no support for these parameters and
 * will get into a bad state if they're negotiated.  Do not enable this
 * unless you know what you're doing */
static void ahc_linux_set_qas(struct scsi_target *starget, int qas)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct ahc_softc *ahc = *((struct ahc_softc **)shost->hostdata);
	struct ahc_tmode_tstate *tstate;
	struct ahc_initiator_tinfo *tinfo 
		= ahc_fetch_transinfo(ahc,
				      starget->channel + 'A',
				      shost->this_id, starget->id, &tstate);
	struct ahc_devinfo devinfo;
	unsigned int ppr_options = tinfo->goal.ppr_options
		& ~MSG_EXT_PPR_QAS_REQ;
	unsigned int period = tinfo->goal.period;
	unsigned long flags;
	struct ahc_syncrate *syncrate;

	if (qas)
		ppr_options |= MSG_EXT_PPR_QAS_REQ;

	ahc_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
			    starget->channel + 'A', ROLE_INITIATOR);
	syncrate = ahc_find_syncrate(ahc, &period, &ppr_options, AHC_SYNCRATE_DT);
	ahc_lock(ahc, &flags);
	ahc_set_syncrate(ahc, &devinfo, syncrate, period, tinfo->goal.offset,
			 ppr_options, AHC_TRANS_GOAL, FALSE);
	ahc_unlock(ahc, &flags);
}

static void ahc_linux_set_iu(struct scsi_target *starget, int iu)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct ahc_softc *ahc = *((struct ahc_softc **)shost->hostdata);
	struct ahc_tmode_tstate *tstate;
	struct ahc_initiator_tinfo *tinfo 
		= ahc_fetch_transinfo(ahc,
				      starget->channel + 'A',
				      shost->this_id, starget->id, &tstate);
	struct ahc_devinfo devinfo;
	unsigned int ppr_options = tinfo->goal.ppr_options
		& ~MSG_EXT_PPR_IU_REQ;
	unsigned int period = tinfo->goal.period;
	unsigned long flags;
	struct ahc_syncrate *syncrate;

	if (iu)
		ppr_options |= MSG_EXT_PPR_IU_REQ;

	ahc_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
			    starget->channel + 'A', ROLE_INITIATOR);
	syncrate = ahc_find_syncrate(ahc, &period, &ppr_options, AHC_SYNCRATE_DT);
	ahc_lock(ahc, &flags);
	ahc_set_syncrate(ahc, &devinfo, syncrate, period, tinfo->goal.offset,
			 ppr_options, AHC_TRANS_GOAL, FALSE);
	ahc_unlock(ahc, &flags);
}
#endif

static void ahc_linux_get_signalling(struct Scsi_Host *shost)
{
	struct ahc_softc *ahc = *(struct ahc_softc **)shost->hostdata;
	unsigned long flags;
	u8 mode;

	if (!(ahc->features & AHC_ULTRA2)) {
		/* non-LVD chipset, may not have SBLKCTL reg */
		spi_signalling(shost) = 
			ahc->features & AHC_HVD ?
			SPI_SIGNAL_HVD :
			SPI_SIGNAL_SE;
		return;
	}

	ahc_lock(ahc, &flags);
	ahc_pause(ahc);
	mode = ahc_inb(ahc, SBLKCTL);
	ahc_unpause(ahc);
	ahc_unlock(ahc, &flags);

	if (mode & ENAB40)
		spi_signalling(shost) = SPI_SIGNAL_LVD;
	else if (mode & ENAB20)
		spi_signalling(shost) = SPI_SIGNAL_SE;
	else
		spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
}

static struct spi_function_template ahc_linux_transport_functions = {
	.set_offset	= ahc_linux_set_offset,
	.show_offset	= 1,
	.set_period	= ahc_linux_set_period,
	.show_period	= 1,
	.set_width	= ahc_linux_set_width,
	.show_width	= 1,
	.set_dt		= ahc_linux_set_dt,
	.show_dt	= 1,
#if 0
	.set_iu		= ahc_linux_set_iu,
	.show_iu	= 1,
	.set_qas	= ahc_linux_set_qas,
	.show_qas	= 1,
#endif
	.get_signalling	= ahc_linux_get_signalling,
};



static int __init
ahc_linux_init(void)
{
	/*
	 * If we've been passed any parameters, process them now.
	 */
	if (aic7xxx)
		aic7xxx_setup(aic7xxx);

	ahc_linux_transport_template =
		spi_attach_transport(&ahc_linux_transport_functions);
	if (!ahc_linux_transport_template)
		return -ENODEV;

	scsi_transport_reserve_device(ahc_linux_transport_template,
				      sizeof(struct ahc_linux_device));

	ahc_linux_pci_init();
	ahc_linux_eisa_init();
	return 0;
}

static void
ahc_linux_exit(void)
{
	ahc_linux_pci_exit();
	ahc_linux_eisa_exit();
	spi_release_transport(ahc_linux_transport_template);
}

module_init(ahc_linux_init);
module_exit(ahc_linux_exit);