summaryrefslogtreecommitdiffstats
path: root/drivers/scsi/seagate.c
blob: e8f146d361c6ce7906e6f93fca70cdddbcc30931 (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
/*
 *    seagate.c Copyright (C) 1992, 1993 Drew Eckhardt
 *      low level scsi driver for ST01/ST02, Future Domain TMC-885,
 *      TMC-950 by Drew Eckhardt <drew@colorado.edu>
 *
 *      Note : TMC-880 boards don't work because they have two bits in
 *              the status register flipped, I'll fix this "RSN"
 *	[why do I have strong feeling that above message is from 1993? :-)
 *	        pavel@ucw.cz]
 *
 *      This card does all the I/O via memory mapped I/O, so there is no need
 *      to check or allocate a region of the I/O address space.
 */

/* 1996 - to use new read{b,w,l}, write{b,w,l}, and phys_to_virt
 * macros, replaced assembler routines with C. There's probably a
 * performance hit, but I only have a cdrom and can't tell. Define
 * SEAGATE_USE_ASM if you want the old assembler code -- SJT
 *
 * 1998-jul-29 - created DPRINTK macros and made it work under 
 * linux 2.1.112, simplified some #defines etc. <pavel@ucw.cz>
 *
 * Aug 2000 - aeb - deleted seagate_st0x_biosparam(). It would try to
 * read the physical disk geometry, a bad mistake. Of course it doesn't
 * matter much what geometry one invents, but on large disks it
 * returned 256 (or more) heads, causing all kind of failures.
 * Of course this means that people might see a different geometry now,
 * so boot parameters may be necessary in some cases.
 */

/*
 * Configuration :
 * To use without BIOS -DOVERRIDE=base_address -DCONTROLLER=FD or SEAGATE
 * -DIRQ will override the default of 5.
 * Note: You can now set these options from the kernel's "command line".
 * The syntax is:
 *
 *     st0x=ADDRESS,IRQ                (for a Seagate controller)
 * or:
 *     tmc8xx=ADDRESS,IRQ              (for a TMC-8xx or TMC-950 controller)
 * eg:
 *     tmc8xx=0xC8000,15
 *
 * will configure the driver for a TMC-8xx style controller using IRQ 15
 * with a base address of 0xC8000.
 *
 * -DARBITRATE 
 *      Will cause the host adapter to arbitrate for the
 *      bus for better SCSI-II compatibility, rather than just
 *      waiting for BUS FREE and then doing its thing.  Should
 *      let us do one command per Lun when I integrate my
 *      reorganization changes into the distribution sources.
 *
 * -DDEBUG=65535
 *      Will activate debug code.
 *
 * -DFAST or -DFAST32 
 *      Will use blind transfers where possible
 *
 * -DPARITY  
 *      This will enable parity.
 *
 * -DSEAGATE_USE_ASM
 *      Will use older seagate assembly code. should be (very small amount)
 *      Faster.
 *
 * -DSLOW_RATE=50
 *      Will allow compatibility with broken devices that don't
 *      handshake fast enough (ie, some CD ROM's) for the Seagate
 *      code.
 *
 *      50 is some number, It will let you specify a default
 *      transfer rate if handshaking isn't working correctly.
 *
 * -DOLDCNTDATASCEME  There is a new sceme to set the CONTROL
 *                    and DATA reigsters which complies more closely
 *                    with the SCSI2 standard. This hopefully eliminates
 *                    the need to swap the order these registers are
 *                    'messed' with. It makes the following two options
 *                    obsolete. To reenable the old sceme define this.
 *
 * The following to options are patches from the SCSI.HOWTO
 *
 * -DSWAPSTAT  This will swap the definitions for STAT_MSG and STAT_CD.
 *
 * -DSWAPCNTDATA  This will swap the order that seagate.c messes with
 *                the CONTROL an DATA registers.
 */

#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/signal.h>
#include <linux/string.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/blkdev.h>
#include <linux/stat.h>
#include <linux/delay.h>

#include <asm/io.h>
#include <asm/system.h>
#include <asm/uaccess.h>

#include "scsi.h"
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_host.h>

#include <scsi/scsi_ioctl.h>

#ifdef DEBUG
#define DPRINTK( when, msg... ) do { if ( (DEBUG & (when)) == (when) ) printk( msg ); } while (0)
#else
#define DPRINTK( when, msg... ) do { } while (0)
#endif
#define DANY( msg... ) DPRINTK( 0xffff, msg );

#ifndef IRQ
#define IRQ 5
#endif

#ifdef FAST32
#define FAST
#endif

#undef LINKED			/* Linked commands are currently broken! */

#if defined(OVERRIDE) && !defined(CONTROLLER)
#error Please use -DCONTROLLER=SEAGATE or -DCONTROLLER=FD to override controller type
#endif

#ifndef __i386__
#undef SEAGATE_USE_ASM
#endif

/*
	Thanks to Brian Antoine for the example code in his Messy-Loss ST-01
		driver, and Mitsugu Suzuki for information on the ST-01
		SCSI host.
*/

/*
	CONTROL defines
*/

#define CMD_RST 		0x01
#define CMD_SEL 		0x02
#define CMD_BSY 		0x04
#define CMD_ATTN    		0x08
#define CMD_START_ARB		0x10
#define CMD_EN_PARITY		0x20
#define CMD_INTR		0x40
#define CMD_DRVR_ENABLE		0x80

/*
	STATUS
*/
#ifdef SWAPSTAT
#define STAT_MSG		0x08
#define STAT_CD			0x02
#else
#define STAT_MSG		0x02
#define STAT_CD			0x08
#endif

#define STAT_BSY		0x01
#define STAT_IO			0x04
#define STAT_REQ		0x10
#define STAT_SEL		0x20
#define STAT_PARITY		0x40
#define STAT_ARB_CMPL		0x80

/* 
	REQUESTS
*/

#define REQ_MASK (STAT_CD |  STAT_IO | STAT_MSG)
#define REQ_DATAOUT 0
#define REQ_DATAIN STAT_IO
#define REQ_CMDOUT STAT_CD
#define REQ_STATIN (STAT_CD | STAT_IO)
#define REQ_MSGOUT (STAT_MSG | STAT_CD)
#define REQ_MSGIN (STAT_MSG | STAT_CD | STAT_IO)

extern volatile int seagate_st0x_timeout;

#ifdef PARITY
#define BASE_CMD CMD_EN_PARITY
#else
#define BASE_CMD  0
#endif

/*
	Debugging code
*/

#define PHASE_BUS_FREE 1
#define PHASE_ARBITRATION 2
#define PHASE_SELECTION 4
#define PHASE_DATAIN 8
#define PHASE_DATAOUT 0x10
#define PHASE_CMDOUT 0x20
#define PHASE_MSGIN 0x40
#define PHASE_MSGOUT 0x80
#define PHASE_STATUSIN 0x100
#define PHASE_ETC (PHASE_DATAIN | PHASE_DATAOUT | PHASE_CMDOUT | PHASE_MSGIN | PHASE_MSGOUT | PHASE_STATUSIN)
#define PRINT_COMMAND 0x200
#define PHASE_EXIT 0x400
#define PHASE_RESELECT 0x800
#define DEBUG_FAST 0x1000
#define DEBUG_SG   0x2000
#define DEBUG_LINKED	0x4000
#define DEBUG_BORKEN	0x8000

/* 
 *	Control options - these are timeouts specified in .01 seconds.
 */

/* 30, 20 work */
#define ST0X_BUS_FREE_DELAY 25
#define ST0X_SELECTION_DELAY 25

#define SEAGATE 1		/* these determine the type of the controller */
#define FD	2

#define ST0X_ID_STR	"Seagate ST-01/ST-02"
#define FD_ID_STR	"TMC-8XX/TMC-950"

static int internal_command (unsigned char target, unsigned char lun,
			     const void *cmnd,
			     void *buff, int bufflen, int reselect);

static int incommand;		/* set if arbitration has finished
				   and we are in some command phase. */

static unsigned int base_address = 0;	/* Where the card ROM starts, used to 
					   calculate memory mapped register
					   location.  */

static void __iomem *st0x_cr_sr;	/* control register write, status
					   register read.  256 bytes in
					   length.
					   Read is status of SCSI BUS, as per 
					   STAT masks.  */

static void __iomem *st0x_dr;	/* data register, read write 256
				   bytes in length.  */

static volatile int st0x_aborted = 0;	/* set when we are aborted, ie by a
					   time out, etc.  */

static unsigned char controller_type = 0;	/* set to SEAGATE for ST0x
						   boards or FD for TMC-8xx
						   boards */
static int irq = IRQ;

module_param(base_address, uint, 0);
module_param(controller_type, byte, 0);
module_param(irq, int, 0);
MODULE_LICENSE("GPL");


#define retcode(result) (((result) << 16) | (message << 8) | status)
#define STATUS ((u8) readb(st0x_cr_sr))
#define DATA ((u8) readb(st0x_dr))
#define WRITE_CONTROL(d) { writeb((d), st0x_cr_sr); }
#define WRITE_DATA(d) { writeb((d), st0x_dr); }

#ifndef OVERRIDE
static unsigned int seagate_bases[] = {
	0xc8000, 0xca000, 0xcc000,
	0xce000, 0xdc000, 0xde000
};

typedef struct {
	const unsigned char *signature;
	unsigned offset;
	unsigned length;
	unsigned char type;
} Signature;

static Signature __initdata signatures[] = {
	{"ST01 v1.7  (C) Copyright 1987 Seagate", 15, 37, SEAGATE},
	{"SCSI BIOS 2.00  (C) Copyright 1987 Seagate", 15, 40, SEAGATE},

/*
 * The following two lines are NOT mistakes.  One detects ROM revision
 * 3.0.0, the other 3.2.  Since seagate has only one type of SCSI adapter,
 * and this is not going to change, the "SEAGATE" and "SCSI" together
 * are probably "good enough"
 */

	{"SEAGATE SCSI BIOS ", 16, 17, SEAGATE},
	{"SEAGATE SCSI BIOS ", 17, 17, SEAGATE},

/*
 * However, future domain makes several incompatible SCSI boards, so specific
 * signatures must be used.
 */

	{"FUTURE DOMAIN CORP. (C) 1986-1989 V5.0C2/14/89", 5, 46, FD},
	{"FUTURE DOMAIN CORP. (C) 1986-1989 V6.0A7/28/89", 5, 46, FD},
	{"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0105/31/90", 5, 47, FD},
	{"FUTURE DOMAIN CORP. (C) 1986-1990 V6.0209/18/90", 5, 47, FD},
	{"FUTURE DOMAIN CORP. (C) 1986-1990 V7.009/18/90", 5, 46, FD},
	{"FUTURE DOMAIN CORP. (C) 1992 V8.00.004/02/92", 5, 44, FD},
	{"IBM F1 BIOS V1.1004/30/92", 5, 25, FD},
	{"FUTURE DOMAIN TMC-950", 5, 21, FD},
	/* Added for 2.2.16 by Matthias_Heidbrink@b.maus.de */
	{"IBM F1 V1.2009/22/93", 5, 25, FD},
};

#define NUM_SIGNATURES ARRAY_SIZE(signatures)
#endif				/* n OVERRIDE */

/*
 * hostno stores the hostnumber, as told to us by the init routine.
 */

static int hostno = -1;
static void seagate_reconnect_intr (int, void *, struct pt_regs *);
static irqreturn_t do_seagate_reconnect_intr (int, void *, struct pt_regs *);
static int seagate_st0x_bus_reset(struct scsi_cmnd *);

#ifdef FAST
static int fast = 1;
#else
#define fast 0
#endif

#ifdef SLOW_RATE
/*
 * Support for broken devices :
 * The Seagate board has a handshaking problem.  Namely, a lack
 * thereof for slow devices.  You can blast 600K/second through
 * it if you are polling for each byte, more if you do a blind
 * transfer.  In the first case, with a fast device, REQ will
 * transition high-low or high-low-high before your loop restarts
 * and you'll have no problems.  In the second case, the board
 * will insert wait states for up to 13.2 usecs for REQ to
 * transition low->high, and everything will work.
 *
 * However, there's nothing in the state machine that says
 * you *HAVE* to see a high-low-high set of transitions before
 * sending the next byte, and slow things like the Trantor CD ROMS
 * will break because of this.
 *
 * So, we need to slow things down, which isn't as simple as it
 * seems.  We can't slow things down period, because then people
 * who don't recompile their kernels will shoot me for ruining
 * their performance.  We need to do it on a case per case basis.
 *
 * The best for performance will be to, only for borken devices
 * (this is stored on a per-target basis in the scsi_devices array)
 *
 * Wait for a low->high transition before continuing with that
 * transfer.  If we timeout, continue anyways.  We don't need
 * a long timeout, because REQ should only be asserted until the
 * corresponding ACK is received and processed.
 *
 * Note that we can't use the system timer for this, because of
 * resolution, and we *really* can't use the timer chip since
 * gettimeofday() and the beeper routines use that.  So,
 * the best thing for us to do will be to calibrate a timing
 * loop in the initialization code using the timer chip before
 * gettimeofday() can screw with it.
 *
 * FIXME: this is broken (not borken :-). Empty loop costs less than
 * loop with ISA access in it! -- pavel@ucw.cz
 */

static int borken_calibration = 0;

static void __init borken_init (void)
{
	register int count = 0, start = jiffies + 1, stop = start + 25;

	/* FIXME: There may be a better approach, this is a straight port for
	   now */
	preempt_disable();
	while (time_before (jiffies, start))
		cpu_relax();
	for (; time_before (jiffies, stop); ++count)
		cpu_relax();
	preempt_enable();

/*
 * Ok, we now have a count for .25 seconds.  Convert to a
 * count per second and divide by transfer rate in K.  */

	borken_calibration = (count * 4) / (SLOW_RATE * 1024);

	if (borken_calibration < 1)
		borken_calibration = 1;
}

static inline void borken_wait (void)
{
	register int count;

	for (count = borken_calibration; count && (STATUS & STAT_REQ); --count)
		cpu_relax();
	     	
#if (DEBUG & DEBUG_BORKEN)
	if (count)
		printk ("scsi%d : borken timeout\n", hostno);
#endif
}

#endif				/* def SLOW_RATE */

/* These beasts only live on ISA, and ISA means 8MHz. Each ULOOP()
 * contains at least one ISA access, which takes more than 0.125
 * usec. So if we loop 8 times time in usec, we are safe.
 */

#define ULOOP( i ) for (clock = i*8;;)
#define TIMEOUT (!(clock--))

int __init seagate_st0x_detect (struct scsi_host_template * tpnt)
{
	struct Scsi_Host *instance;
	int i, j;
	unsigned long cr, dr;

	tpnt->proc_name = "seagate";
/*
 *	First, we try for the manual override.
 */
	DANY ("Autodetecting ST0x / TMC-8xx\n");

	if (hostno != -1) {
		printk (KERN_ERR "seagate_st0x_detect() called twice?!\n");
		return 0;
	}

/* If the user specified the controller type from the command line,
   controller_type will be non-zero, so don't try to detect one */

	if (!controller_type) {
#ifdef OVERRIDE
		base_address = OVERRIDE;
		controller_type = CONTROLLER;

		DANY ("Base address overridden to %x, controller type is %s\n",
		      base_address,
		      controller_type == SEAGATE ? "SEAGATE" : "FD");
#else				/* OVERRIDE */
/*
 * 	To detect this card, we simply look for the signature
 *      from the BIOS version notice in all the possible locations
 *      of the ROM's.  This has a nice side effect of not trashing
 *      any register locations that might be used by something else.
 *
 * XXX - note that we probably should be probing the address
 * space for the on-board RAM instead.
 */

		for (i = 0; i < ARRAY_SIZE(seagate_bases); ++i) {
			void __iomem *p = ioremap(seagate_bases[i], 0x2000);
			if (!p)
				continue;
			for (j = 0; j < NUM_SIGNATURES; ++j)
				if (check_signature(p + signatures[j].offset, signatures[j].signature, signatures[j].length)) {
					base_address = seagate_bases[i];
					controller_type = signatures[j].type;
					break;
				}
			iounmap(p);
		}
#endif				/* OVERRIDE */
	}
	/* (! controller_type) */
	tpnt->this_id = (controller_type == SEAGATE) ? 7 : 6;
	tpnt->name = (controller_type == SEAGATE) ? ST0X_ID_STR : FD_ID_STR;

	if (!base_address) {
		printk(KERN_INFO "seagate: ST0x/TMC-8xx not detected.\n");
		return 0;
	}

	cr = base_address + (controller_type == SEAGATE ? 0x1a00 : 0x1c00);
	dr = cr + 0x200;
	st0x_cr_sr = ioremap(cr, 0x100);
	st0x_dr = ioremap(dr, 0x100);

	DANY("%s detected. Base address = %x, cr = %x, dr = %x\n",
	      tpnt->name, base_address, cr, dr);

	/*
	 *	At all times, we will use IRQ 5.  Should also check for IRQ3
	 *	if we lose our first interrupt.
	 */
	instance = scsi_register (tpnt, 0);
	if (instance == NULL)
		return 0;

	hostno = instance->host_no;
	if (request_irq (irq, do_seagate_reconnect_intr, IRQF_DISABLED, (controller_type == SEAGATE) ? "seagate" : "tmc-8xx", instance)) {
		printk(KERN_ERR "scsi%d : unable to allocate IRQ%d\n", hostno, irq);
		return 0;
	}
	instance->irq = irq;
	instance->io_port = base_address;
#ifdef SLOW_RATE
	printk(KERN_INFO "Calibrating borken timer... ");
	borken_init();
	printk(" %d cycles per transfer\n", borken_calibration);
#endif
	printk (KERN_INFO "This is one second... ");
	{
		int clock;
		ULOOP (1 * 1000 * 1000) {
			STATUS;
			if (TIMEOUT)
				break;
		}
	}

	printk ("done, %s options:"
#ifdef ARBITRATE
		" ARBITRATE"
#endif
#ifdef DEBUG
		" DEBUG"
#endif
#ifdef FAST
		" FAST"
#ifdef FAST32
		"32"
#endif
#endif
#ifdef LINKED
		" LINKED"
#endif
#ifdef PARITY
		" PARITY"
#endif
#ifdef SEAGATE_USE_ASM
		" SEAGATE_USE_ASM"
#endif
#ifdef SLOW_RATE
		" SLOW_RATE"
#endif
#ifdef SWAPSTAT
		" SWAPSTAT"
#endif
#ifdef SWAPCNTDATA
		" SWAPCNTDATA"
#endif
		"\n", tpnt->name);
	return 1;
}

static const char *seagate_st0x_info (struct Scsi_Host *shpnt)
{
	static char buffer[64];

	snprintf(buffer, 64, "%s at irq %d, address 0x%05X",
		 (controller_type == SEAGATE) ? ST0X_ID_STR : FD_ID_STR,
		 irq, base_address);
	return buffer;
}

/*
 * These are our saved pointers for the outstanding command that is
 * waiting for a reconnect
 */

static unsigned char current_target, current_lun;
static unsigned char *current_cmnd, *current_data;
static int current_nobuffs;
static struct scatterlist *current_buffer;
static int current_bufflen;

#ifdef LINKED
/*
 * linked_connected indicates whether or not we are currently connected to
 * linked_target, linked_lun and in an INFORMATION TRANSFER phase,
 * using linked commands.
 */

static int linked_connected = 0;
static unsigned char linked_target, linked_lun;
#endif

static void (*done_fn) (struct scsi_cmnd *) = NULL;
static struct scsi_cmnd *SCint = NULL;

/*
 * These control whether or not disconnect / reconnect will be attempted,
 * or are being attempted.
 */

#define NO_RECONNECT    0
#define RECONNECT_NOW   1
#define CAN_RECONNECT   2

/*
 * LINKED_RIGHT indicates that we are currently connected to the correct target
 * for this command, LINKED_WRONG indicates that we are connected to the wrong
 * target. Note that these imply CAN_RECONNECT and require defined(LINKED).
 */

#define LINKED_RIGHT    3
#define LINKED_WRONG    4

/*
 * This determines if we are expecting to reconnect or not.
 */

static int should_reconnect = 0;

/*
 * The seagate_reconnect_intr routine is called when a target reselects the
 * host adapter.  This occurs on the interrupt triggered by the target
 * asserting SEL.
 */

static irqreturn_t do_seagate_reconnect_intr(int irq, void *dev_id,
						struct pt_regs *regs)
{
	unsigned long flags;
	struct Scsi_Host *dev = dev_id;
	
	spin_lock_irqsave (dev->host_lock, flags);
	seagate_reconnect_intr (irq, dev_id, regs);
	spin_unlock_irqrestore (dev->host_lock, flags);
	return IRQ_HANDLED;
}

static void seagate_reconnect_intr (int irq, void *dev_id, struct pt_regs *regs)
{
	int temp;
	struct scsi_cmnd *SCtmp;

	DPRINTK (PHASE_RESELECT, "scsi%d : seagate_reconnect_intr() called\n", hostno);

	if (!should_reconnect)
		printk(KERN_WARNING "scsi%d: unexpected interrupt.\n", hostno);
	else {
		should_reconnect = 0;

		DPRINTK (PHASE_RESELECT, "scsi%d : internal_command(%d, %08x, %08x, RECONNECT_NOW\n", 
			hostno, current_target, current_data, current_bufflen);

		temp = internal_command (current_target, current_lun, current_cmnd, current_data, current_bufflen, RECONNECT_NOW);

		if (msg_byte(temp) != DISCONNECT) {
			if (done_fn) {
				DPRINTK(PHASE_RESELECT, "scsi%d : done_fn(%d,%08x)", hostno, hostno, temp);
				if (!SCint)
					panic ("SCint == NULL in seagate");
				SCtmp = SCint;
				SCint = NULL;
				SCtmp->result = temp;
				done_fn(SCtmp);
			} else
				printk(KERN_ERR "done_fn() not defined.\n");
		}
	}
}

/*
 * The seagate_st0x_queue_command() function provides a queued interface
 * to the seagate SCSI driver.  Basically, it just passes control onto the
 * seagate_command() function, after fixing it so that the done_fn()
 * is set to the one passed to the function.  We have to be very careful,
 * because there are some commands on some devices that do not disconnect,
 * and if we simply call the done_fn when the command is done then another
 * command is started and queue_command is called again...  We end up
 * overflowing the kernel stack, and this tends not to be such a good idea.
 */

static int recursion_depth = 0;

static int seagate_st0x_queue_command(struct scsi_cmnd * SCpnt,
				      void (*done) (struct scsi_cmnd *))
{
	int result, reconnect;
	struct scsi_cmnd *SCtmp;

	DANY ("seagate: que_command");
	done_fn = done;
	current_target = SCpnt->device->id;
	current_lun = SCpnt->device->lun;
	current_cmnd = SCpnt->cmnd;
	current_data = (unsigned char *) SCpnt->request_buffer;
	current_bufflen = SCpnt->request_bufflen;
	SCint = SCpnt;
	if (recursion_depth)
		return 1;
	recursion_depth++;
	do {
#ifdef LINKED
		/*
		 * Set linked command bit in control field of SCSI command.
		 */

		current_cmnd[SCpnt->cmd_len] |= 0x01;
		if (linked_connected) {
			DPRINTK (DEBUG_LINKED, "scsi%d : using linked commands, current I_T_L nexus is ", hostno);
			if (linked_target == current_target && linked_lun == current_lun) 
			{
				DPRINTK(DEBUG_LINKED, "correct\n");
				reconnect = LINKED_RIGHT;
			} else {
				DPRINTK(DEBUG_LINKED, "incorrect\n");
				reconnect = LINKED_WRONG;
			}
		} else
#endif				/* LINKED */
			reconnect = CAN_RECONNECT;

		result = internal_command(SCint->device->id, SCint->device->lun, SCint->cmnd,
				      SCint->request_buffer, SCint->request_bufflen, reconnect);
		if (msg_byte(result) == DISCONNECT)
			break;
		SCtmp = SCint;
		SCint = NULL;
		SCtmp->result = result;
		done_fn(SCtmp);
	}
	while (SCint);
	recursion_depth--;
	return 0;
}

static int internal_command (unsigned char target, unsigned char lun,
		  const void *cmnd, void *buff, int bufflen, int reselect)
{
	unsigned char *data = NULL;
	struct scatterlist *buffer = NULL;
	int clock, temp, nobuffs = 0, done = 0, len = 0;
#ifdef DEBUG
	int transfered = 0, phase = 0, newphase;
#endif
	register unsigned char status_read;
	unsigned char tmp_data, tmp_control, status = 0, message = 0;
	unsigned transfersize = 0, underflow = 0;
#ifdef SLOW_RATE
	int borken = (int) SCint->device->borken;	/* Does the current target require
							   Very Slow I/O ?  */
#endif

	incommand = 0;
	st0x_aborted = 0;

#if (DEBUG & PRINT_COMMAND)
	printk("scsi%d : target = %d, command = ", hostno, target);
	__scsi_print_command((unsigned char *) cmnd);
#endif

#if (DEBUG & PHASE_RESELECT)
	switch (reselect) {
	case RECONNECT_NOW:
		printk("scsi%d : reconnecting\n", hostno);
		break;
#ifdef LINKED
	case LINKED_RIGHT:
		printk("scsi%d : connected, can reconnect\n", hostno);
		break;
	case LINKED_WRONG:
		printk("scsi%d : connected to wrong target, can reconnect\n",
			hostno);
		break;
#endif
	case CAN_RECONNECT:
		printk("scsi%d : allowed to reconnect\n", hostno);
		break;
	default:
		printk("scsi%d : not allowed to reconnect\n", hostno);
	}
#endif

	if (target == (controller_type == SEAGATE ? 7 : 6))
		return DID_BAD_TARGET;

	/*
	 *	We work it differently depending on if this is is "the first time,"
	 *      or a reconnect.  If this is a reselect phase, then SEL will
	 *      be asserted, and we must skip selection / arbitration phases.
	 */

	switch (reselect) {
	case RECONNECT_NOW:
		DPRINTK (PHASE_RESELECT, "scsi%d : phase RESELECT \n", hostno);
		/*
		 *	At this point, we should find the logical or of our ID
		 *	and the original target's ID on the BUS, with BSY, SEL,
		 *	and I/O signals asserted.
		 *
		 *      After ARBITRATION phase is completed, only SEL, BSY,
		 *	and the target ID are asserted.  A valid initiator ID
		 *	is not on the bus until IO is asserted, so we must wait
		 *	for that.
		 */
		ULOOP (100 * 1000) {
			temp = STATUS;
			if ((temp & STAT_IO) && !(temp & STAT_BSY))
				break;
			if (TIMEOUT) {
				DPRINTK (PHASE_RESELECT, "scsi%d : RESELECT timed out while waiting for IO .\n", hostno);
				return (DID_BAD_INTR << 16);
			}
		}

		/*
		 *	After I/O is asserted by the target, we can read our ID
		 *	and its ID off of the BUS.
		 */

		if (!((temp = DATA) & (controller_type == SEAGATE ? 0x80 : 0x40))) {
			DPRINTK (PHASE_RESELECT, "scsi%d : detected reconnect request to different target.\n\tData bus = %d\n", hostno, temp);
			return (DID_BAD_INTR << 16);
		}

		if (!(temp & (1 << current_target))) {
			printk(KERN_WARNING "scsi%d : Unexpected reselect interrupt.  Data bus = %d\n", hostno, temp);
			return (DID_BAD_INTR << 16);
		}

		buffer = current_buffer;
		cmnd = current_cmnd;	/* WDE add */
		data = current_data;	/* WDE add */
		len = current_bufflen;	/* WDE add */
		nobuffs = current_nobuffs;

		/*
		 *	We have determined that we have been selected.  At this
		 *	point, we must respond to the reselection by asserting
		 *	BSY ourselves
		 */

#if 1
		WRITE_CONTROL (BASE_CMD | CMD_DRVR_ENABLE | CMD_BSY);
#else
		WRITE_CONTROL (BASE_CMD | CMD_BSY);
#endif

		/*
		 *	The target will drop SEL, and raise BSY, at which time
		 *	we must drop BSY.
		 */

		ULOOP (100 * 1000) {
			if (!(STATUS & STAT_SEL))
				break;
			if (TIMEOUT) {
				WRITE_CONTROL (BASE_CMD | CMD_INTR);
				DPRINTK (PHASE_RESELECT, "scsi%d : RESELECT timed out while waiting for SEL.\n", hostno);
				return (DID_BAD_INTR << 16);
			}
		}
		WRITE_CONTROL (BASE_CMD);
		/*
		 *	At this point, we have connected with the target
		 *	and can get on with our lives.
		 */
		break;
	case CAN_RECONNECT:
#ifdef LINKED
		/*
		 * This is a bletcherous hack, just as bad as the Unix #!
		 * interpreter stuff. If it turns out we are using the wrong
		 * I_T_L nexus, the easiest way to deal with it is to go into
		 *  our INFORMATION TRANSFER PHASE code, send a ABORT
		 * message on MESSAGE OUT phase, and then loop back to here.
		 */
connect_loop:
#endif
		DPRINTK (PHASE_BUS_FREE, "scsi%d : phase = BUS FREE \n", hostno);

		/*
		 *    BUS FREE PHASE
		 *
		 *      On entry, we make sure that the BUS is in a BUS FREE
		 *      phase, by insuring that both BSY and SEL are low for
		 *      at least one bus settle delay.  Several reads help
		 *      eliminate wire glitch.
		 */

#ifndef ARBITRATE
#error FIXME: this is broken: we may not use jiffies here - we are under cli(). It will hardlock.
		clock = jiffies + ST0X_BUS_FREE_DELAY;

		while (((STATUS | STATUS | STATUS) & (STAT_BSY | STAT_SEL)) && (!st0x_aborted) && time_before (jiffies, clock))
			cpu_relax();

		if (time_after (jiffies, clock))
			return retcode (DID_BUS_BUSY);
		else if (st0x_aborted)
			return retcode (st0x_aborted);
#endif
		DPRINTK (PHASE_SELECTION, "scsi%d : phase = SELECTION\n", hostno);

		clock = jiffies + ST0X_SELECTION_DELAY;

		/*
		 * Arbitration/selection procedure :
		 * 1.  Disable drivers
		 * 2.  Write HOST adapter address bit
		 * 3.  Set start arbitration.
		 * 4.  We get either ARBITRATION COMPLETE or SELECT at this
		 *     point.
		 * 5.  OR our ID and targets on bus.
		 * 6.  Enable SCSI drivers and asserted SEL and ATTN
		 */

#ifdef ARBITRATE
		/* FIXME: verify host lock is always held here */
		WRITE_CONTROL(0);
		WRITE_DATA((controller_type == SEAGATE) ? 0x80 : 0x40);
		WRITE_CONTROL(CMD_START_ARB);

		ULOOP (ST0X_SELECTION_DELAY * 10000) {
			status_read = STATUS;
			if (status_read & STAT_ARB_CMPL)
				break;
			if (st0x_aborted)	/* FIXME: What? We are going to do something even after abort? */
				break;
			if (TIMEOUT || (status_read & STAT_SEL)) {
				printk(KERN_WARNING "scsi%d : arbitration lost or timeout.\n", hostno);
				WRITE_CONTROL (BASE_CMD);
				return retcode (DID_NO_CONNECT);
			}
		}
		DPRINTK (PHASE_SELECTION, "scsi%d : arbitration complete\n", hostno);
#endif

		/*
		 *    When the SCSI device decides that we're gawking at it, 
		 *    it will respond by asserting BUSY on the bus.
		 *
		 *    Note : the Seagate ST-01/02 product manual says that we
		 *    should twiddle the DATA register before the control
		 *    register. However, this does not work reliably so we do
		 *    it the other way around.
		 *
		 *    Probably could be a problem with arbitration too, we
		 *    really should try this with a SCSI protocol or logic 
		 *    analyzer to see what is going on.
		 */
		tmp_data = (unsigned char) ((1 << target) | (controller_type == SEAGATE ? 0x80 : 0x40));
		tmp_control = BASE_CMD | CMD_DRVR_ENABLE | CMD_SEL | (reselect ? CMD_ATTN : 0);

		/* FIXME: verify host lock is always held here */
#ifdef OLDCNTDATASCEME
#ifdef SWAPCNTDATA
		WRITE_CONTROL (tmp_control);
		WRITE_DATA (tmp_data);
#else
		WRITE_DATA (tmp_data);
		WRITE_CONTROL (tmp_control);
#endif
#else
		tmp_control ^= CMD_BSY;	/* This is guesswork. What used to be in driver    */
		WRITE_CONTROL (tmp_control);	/* could never work: it sent data into control     */
		WRITE_DATA (tmp_data);	/* register and control info into data. Hopefully  */
		tmp_control ^= CMD_BSY;	/* fixed, but order of first two may be wrong.     */
		WRITE_CONTROL (tmp_control);	/* -- pavel@ucw.cz   */
#endif

		ULOOP (250 * 1000) {
			if (st0x_aborted) {
				/*
				 *	If we have been aborted, and we have a
				 *	command in progress, IE the target 
				 *	still has BSY asserted, then we will
				 *	reset the bus, and notify the midlevel
				 *	driver to expect sense.
				 */

				WRITE_CONTROL (BASE_CMD);
				if (STATUS & STAT_BSY) {
					printk(KERN_WARNING "scsi%d : BST asserted after we've been aborted.\n", hostno);
					seagate_st0x_bus_reset(NULL);
					return retcode (DID_RESET);
				}
				return retcode (st0x_aborted);
			}
			if (STATUS & STAT_BSY)
				break;
			if (TIMEOUT) {
				DPRINTK (PHASE_SELECTION, "scsi%d : NO CONNECT with target %d, stat = %x \n", hostno, target, STATUS);
				return retcode (DID_NO_CONNECT);
			}
		}

		/* Establish current pointers.  Take into account scatter / gather */

		if ((nobuffs = SCint->use_sg)) {
#if (DEBUG & DEBUG_SG)
			{
				int i;
				printk("scsi%d : scatter gather requested, using %d buffers.\n", hostno, nobuffs);
				for (i = 0; i < nobuffs; ++i)
					printk("scsi%d : buffer %d address = %p length = %d\n",
					     hostno, i,
					     page_address(buffer[i].page) + buffer[i].offset,
					     buffer[i].length);
			}
#endif

			buffer = (struct scatterlist *) SCint->request_buffer;
			len = buffer->length;
			data = page_address(buffer->page) + buffer->offset;
		} else {
			DPRINTK (DEBUG_SG, "scsi%d : scatter gather not requested.\n", hostno);
			buffer = NULL;
			len = SCint->request_bufflen;
			data = (unsigned char *) SCint->request_buffer;
		}

		DPRINTK (PHASE_DATAIN | PHASE_DATAOUT, "scsi%d : len = %d\n",
			 hostno, len);

		break;
#ifdef LINKED
	case LINKED_RIGHT:
		break;
	case LINKED_WRONG:
		break;
#endif
	}			/* end of switch(reselect) */

	/*
	 *    There are several conditions under which we wish to send a message :
	 *      1.  When we are allowing disconnect / reconnect, and need to
	 *	establish the I_T_L nexus via an IDENTIFY with the DiscPriv bit
	 *	set.
	 *
	 *      2.  When we are doing linked commands, are have the wrong I_T_L
	 *	nexus established and want to send an ABORT message.
	 */

	/* GCC does not like an ifdef inside a macro, so do it the hard way. */
#ifdef LINKED
	WRITE_CONTROL (BASE_CMD | CMD_DRVR_ENABLE | (((reselect == CAN_RECONNECT)|| (reselect == LINKED_WRONG))? CMD_ATTN : 0));
#else
	WRITE_CONTROL (BASE_CMD | CMD_DRVR_ENABLE | (((reselect == CAN_RECONNECT))? CMD_ATTN : 0));
#endif

	/*
	 *    INFORMATION TRANSFER PHASE
	 *
	 *      The nasty looking read / write inline assembler loops we use for
	 *      DATAIN and DATAOUT phases are approximately 4-5 times as fast as
	 *      the 'C' versions - since we're moving 1024 bytes of data, this
	 *      really adds up.
	 *
	 *      SJT: The nasty-looking assembler is gone, so it's slower.
	 *
	 */

	DPRINTK (PHASE_ETC, "scsi%d : phase = INFORMATION TRANSFER\n", hostno);

	incommand = 1;
	transfersize = SCint->transfersize;
	underflow = SCint->underflow;

	/*
	 *	Now, we poll the device for status information,
	 *      and handle any requests it makes.  Note that since we are unsure
	 *	of how much data will be flowing across the system, etc and
	 *	cannot make reasonable timeouts, that we will instead have the
	 *	midlevel driver handle any timeouts that occur in this phase.
	 */

	while (((status_read = STATUS) & STAT_BSY) && !st0x_aborted && !done) {
#ifdef PARITY
		if (status_read & STAT_PARITY) {
			printk(KERN_ERR "scsi%d : got parity error\n", hostno);
			st0x_aborted = DID_PARITY;
		}
#endif
		if (status_read & STAT_REQ) {
#if ((DEBUG & PHASE_ETC) == PHASE_ETC)
			if ((newphase = (status_read & REQ_MASK)) != phase) {
				phase = newphase;
				switch (phase) {
				case REQ_DATAOUT:
					printk ("scsi%d : phase = DATA OUT\n", hostno);
					break;
				case REQ_DATAIN:
					printk ("scsi%d : phase = DATA IN\n", hostno);
					break;
				case REQ_CMDOUT:
					printk
					    ("scsi%d : phase = COMMAND OUT\n", hostno);
					break;
				case REQ_STATIN:
					printk ("scsi%d : phase = STATUS IN\n",	hostno);
					break;
				case REQ_MSGOUT:
					printk
					    ("scsi%d : phase = MESSAGE OUT\n", hostno);
					break;
				case REQ_MSGIN:
					printk ("scsi%d : phase = MESSAGE IN\n", hostno);
					break;
				default:
					printk ("scsi%d : phase = UNKNOWN\n", hostno);
					st0x_aborted = DID_ERROR;
				}
			}
#endif
			switch (status_read & REQ_MASK) {
			case REQ_DATAOUT:
				/*
				 * If we are in fast mode, then we simply splat
				 * the data out in word-sized chunks as fast as
				 * we can.
				 */

				if (!len) {
#if 0
					printk("scsi%d: underflow to target %d lun %d \n", hostno, target, lun);
					st0x_aborted = DID_ERROR;
					fast = 0;
#endif
					break;
				}

				if (fast && transfersize
				    && !(len % transfersize)
				    && (len >= transfersize)
#ifdef FAST32
				    && !(transfersize % 4)
#endif
				    ) {
					DPRINTK (DEBUG_FAST,
						 "scsi%d : FAST transfer, underflow = %d, transfersize = %d\n"
						 "         len = %d, data = %08x\n",
						 hostno, SCint->underflow,
						 SCint->transfersize, len,
						 data);

			/* SJT: Start. Fast Write */
#ifdef SEAGATE_USE_ASM
					__asm__ ("cld\n\t"
#ifdef FAST32
						 "shr $2, %%ecx\n\t"
						 "1:\t"
						 "lodsl\n\t"
						 "movl %%eax, (%%edi)\n\t"
#else
						 "1:\t"
						 "lodsb\n\t"
						 "movb %%al, (%%edi)\n\t"
#endif
						 "loop 1b;"
				      /* output */ :
				      /* input */ :"D" (st0x_dr),
						 "S"
						 (data),
						 "c" (SCint->transfersize)
/* clobbered */
				      :	 "eax", "ecx",
						 "esi");
#else				/* SEAGATE_USE_ASM */
					memcpy_toio(st0x_dr, data, transfersize);
#endif				/* SEAGATE_USE_ASM */
/* SJT: End */
					len -= transfersize;
					data += transfersize;
					DPRINTK (DEBUG_FAST, "scsi%d : FAST transfer complete len = %d data = %08x\n", hostno, len, data);
				} else {
					/*
					 *    We loop as long as we are in a 
					 *    data out phase, there is data to
					 *    send, and BSY is still active.
					 */

/* SJT: Start. Slow Write. */
#ifdef SEAGATE_USE_ASM

					int __dummy_1, __dummy_2;

/*
 *      We loop as long as we are in a data out phase, there is data to send, 
 *      and BSY is still active.
 */
/* Local variables : len = ecx , data = esi, 
                     st0x_cr_sr = ebx, st0x_dr =  edi
*/
					__asm__ (
							/* Test for any data here at all. */
							"orl %%ecx, %%ecx\n\t"
							"jz 2f\n\t" "cld\n\t"
/*                    "movl st0x_cr_sr, %%ebx\n\t"  */
/*                    "movl st0x_dr, %%edi\n\t"  */
							"1:\t"
							"movb (%%ebx), %%al\n\t"
							/* Test for BSY */
							"test $1, %%al\n\t"
							"jz 2f\n\t"
							/* Test for data out phase - STATUS & REQ_MASK should be 
							   REQ_DATAOUT, which is 0. */
							"test $0xe, %%al\n\t"
							"jnz 2f\n\t"
							/* Test for REQ */
							"test $0x10, %%al\n\t"
							"jz 1b\n\t"
							"lodsb\n\t"
							"movb %%al, (%%edi)\n\t"
							"loop 1b\n\t" "2:\n"
				      /* output */ :"=S" (data), "=c" (len),
							"=b"
							(__dummy_1),
							"=D" (__dummy_2)
/* input */
				      :		"0" (data), "1" (len),
							"2" (st0x_cr_sr),
							"3" (st0x_dr)
/* clobbered */
				      :		"eax");
#else				/* SEAGATE_USE_ASM */
					while (len) {
						unsigned char stat;

						stat = STATUS;
						if (!(stat & STAT_BSY)
						    || ((stat & REQ_MASK) !=
							REQ_DATAOUT))
							break;
						if (stat & STAT_REQ) {
							WRITE_DATA (*data++);
							--len;
						}
					}
#endif				/* SEAGATE_USE_ASM */
/* SJT: End. */
				}

				if (!len && nobuffs) {
					--nobuffs;
					++buffer;
					len = buffer->length;
					data = page_address(buffer->page) + buffer->offset;
					DPRINTK (DEBUG_SG,
						 "scsi%d : next scatter-gather buffer len = %d address = %08x\n",
						 hostno, len, data);
				}
				break;

			case REQ_DATAIN:
#ifdef SLOW_RATE
				if (borken) {
#if (DEBUG & (PHASE_DATAIN))
					transfered += len;
#endif
					for (; len && (STATUS & (REQ_MASK | STAT_REQ)) == (REQ_DATAIN | STAT_REQ); --len) {
						*data++ = DATA;
						borken_wait();
					}
#if (DEBUG & (PHASE_DATAIN))
					transfered -= len;
#endif
				} else
#endif

					if (fast && transfersize
					    && !(len % transfersize)
					    && (len >= transfersize)
#ifdef FAST32
					    && !(transfersize % 4)
#endif
				    ) {
					DPRINTK (DEBUG_FAST,
						 "scsi%d : FAST transfer, underflow = %d, transfersize = %d\n"
						 "         len = %d, data = %08x\n",
						 hostno, SCint->underflow,
						 SCint->transfersize, len,
						 data);

/* SJT: Start. Fast Read */
#ifdef SEAGATE_USE_ASM
					__asm__ ("cld\n\t"
#ifdef FAST32
						 "shr $2, %%ecx\n\t"
						 "1:\t"
						 "movl (%%esi), %%eax\n\t"
						 "stosl\n\t"
#else
						 "1:\t"
						 "movb (%%esi), %%al\n\t"
						 "stosb\n\t"
#endif
						 "loop 1b\n\t"
				      /* output */ :
				      /* input */ :"S" (st0x_dr),
						 "D"
						 (data),
						 "c" (SCint->transfersize)
/* clobbered */
				      :	 "eax", "ecx",
						 "edi");
#else				/* SEAGATE_USE_ASM */
					memcpy_fromio(data, st0x_dr, len);
#endif				/* SEAGATE_USE_ASM */
/* SJT: End */
					len -= transfersize;
					data += transfersize;
#if (DEBUG & PHASE_DATAIN)
					printk ("scsi%d: transfered += %d\n", hostno, transfersize);
					transfered += transfersize;
#endif

					DPRINTK (DEBUG_FAST, "scsi%d : FAST transfer complete len = %d data = %08x\n", hostno, len, data);
				} else {

#if (DEBUG & PHASE_DATAIN)
					printk ("scsi%d: transfered += %d\n", hostno, len);
					transfered += len;	/* Assume we'll transfer it all, then
								   subtract what we *didn't* transfer */
#endif

/*
 *	We loop as long as we are in a data in phase, there is room to read,
 *      and BSY is still active
 */

/* SJT: Start. */
#ifdef SEAGATE_USE_ASM

					int __dummy_3, __dummy_4;

/* Dummy clobbering variables for the new gcc-2.95 */

/*
 *      We loop as long as we are in a data in phase, there is room to read, 
 *      and BSY is still active
 */
					/* Local variables : ecx = len, edi = data
					   esi = st0x_cr_sr, ebx = st0x_dr */
					__asm__ (
							/* Test for room to read */
							"orl %%ecx, %%ecx\n\t"
							"jz 2f\n\t" "cld\n\t"
/*                "movl st0x_cr_sr, %%esi\n\t"  */
/*                "movl st0x_dr, %%ebx\n\t"  */
							"1:\t"
							"movb (%%esi), %%al\n\t"
							/* Test for BSY */
							"test $1, %%al\n\t"
							"jz 2f\n\t"
							/* Test for data in phase - STATUS & REQ_MASK should be REQ_DATAIN, 
							   = STAT_IO, which is 4. */
							"movb $0xe, %%ah\n\t"
							"andb %%al, %%ah\n\t"
							"cmpb $0x04, %%ah\n\t"
							"jne 2f\n\t"
							/* Test for REQ */
							"test $0x10, %%al\n\t"
							"jz 1b\n\t"
							"movb (%%ebx), %%al\n\t"
							"stosb\n\t"
							"loop 1b\n\t" "2:\n"
				      /* output */ :"=D" (data), "=c" (len),
							"=S"
							(__dummy_3),
							"=b" (__dummy_4)
/* input */
				      :		"0" (data), "1" (len),
							"2" (st0x_cr_sr),
							"3" (st0x_dr)
/* clobbered */
				      :		"eax");
#else				/* SEAGATE_USE_ASM */
					while (len) {
						unsigned char stat;

						stat = STATUS;
						if (!(stat & STAT_BSY)
						    || ((stat & REQ_MASK) !=
							REQ_DATAIN))
							break;
						if (stat & STAT_REQ) {
							*data++ = DATA;
							--len;
						}
					}
#endif				/* SEAGATE_USE_ASM */
/* SJT: End. */
#if (DEBUG & PHASE_DATAIN)
					printk ("scsi%d: transfered -= %d\n", hostno, len);
					transfered -= len;	/* Since we assumed all of Len got  *
								   transfered, correct our mistake */
#endif
				}

				if (!len && nobuffs) {
					--nobuffs;
					++buffer;
					len = buffer->length;
					data = page_address(buffer->page) + buffer->offset;
					DPRINTK (DEBUG_SG, "scsi%d : next scatter-gather buffer len = %d address = %08x\n", hostno, len, data);
				}
				break;

			case REQ_CMDOUT:
				while (((status_read = STATUS) & STAT_BSY) &&
				       ((status_read & REQ_MASK) == REQ_CMDOUT))
					if (status_read & STAT_REQ) {
						WRITE_DATA (*(const unsigned char *) cmnd);
						cmnd = 1 + (const unsigned char *)cmnd;
#ifdef SLOW_RATE
						if (borken)
							borken_wait ();
#endif
					}
				break;

			case REQ_STATIN:
				status = DATA;
				break;

			case REQ_MSGOUT:
				/*
				 *	We can only have sent a MSG OUT if we
				 *	requested to do this by raising ATTN.
				 *	So, we must drop ATTN.
				 */
				WRITE_CONTROL (BASE_CMD | CMD_DRVR_ENABLE);
				/*
				 *	If we are reconnecting, then we must 
				 *	send an IDENTIFY message in response
				 *	to MSGOUT.
				 */
				switch (reselect) {
				case CAN_RECONNECT:
					WRITE_DATA (IDENTIFY (1, lun));
					DPRINTK (PHASE_RESELECT | PHASE_MSGOUT, "scsi%d : sent IDENTIFY message.\n", hostno);
					break;
#ifdef LINKED
				case LINKED_WRONG:
					WRITE_DATA (ABORT);
					linked_connected = 0;
					reselect = CAN_RECONNECT;
					goto connect_loop;
					DPRINTK (PHASE_MSGOUT | DEBUG_LINKED, "scsi%d : sent ABORT message to cancel incorrect I_T_L nexus.\n", hostno);
#endif					/* LINKED */
					DPRINTK (DEBUG_LINKED, "correct\n");
				default:
					WRITE_DATA (NOP);
					printk("scsi%d : target %d requested MSGOUT, sent NOP message.\n", hostno, target);
				}
				break;

			case REQ_MSGIN:
				switch (message = DATA) {
				case DISCONNECT:
					DANY("seagate: deciding to disconnect\n");
					should_reconnect = 1;
					current_data = data;	/* WDE add */
					current_buffer = buffer;
					current_bufflen = len;	/* WDE add */
					current_nobuffs = nobuffs;
#ifdef LINKED
					linked_connected = 0;
#endif
					done = 1;
					DPRINTK ((PHASE_RESELECT | PHASE_MSGIN), "scsi%d : disconnected.\n", hostno);
					break;

#ifdef LINKED
				case LINKED_CMD_COMPLETE:
				case LINKED_FLG_CMD_COMPLETE:
#endif
				case COMMAND_COMPLETE:
					/*
					 * Note : we should check for underflow here.
					 */
					DPRINTK(PHASE_MSGIN, "scsi%d : command complete.\n", hostno);
					done = 1;
					break;
				case ABORT:
					DPRINTK(PHASE_MSGIN, "scsi%d : abort message.\n", hostno);
					done = 1;
					break;
				case SAVE_POINTERS:
					current_buffer = buffer;
					current_bufflen = len;	/* WDE add */
					current_data = data;	/* WDE mod */
					current_nobuffs = nobuffs;
					DPRINTK (PHASE_MSGIN, "scsi%d : pointers saved.\n", hostno);
					break;
				case RESTORE_POINTERS:
					buffer = current_buffer;
					cmnd = current_cmnd;
					data = current_data;	/* WDE mod */
					len = current_bufflen;
					nobuffs = current_nobuffs;
					DPRINTK(PHASE_MSGIN, "scsi%d : pointers restored.\n", hostno);
					break;
				default:

					/*
					 *	IDENTIFY distinguishes itself
					 *	from the other messages by 
					 *	setting the high bit.
					 *
					 *      Note : we need to handle at 
					 *	least one outstanding command
					 *	per LUN, and need to hash the 
					 *	SCSI command for that I_T_L
					 *	nexus based on the known ID 
					 *	(at this point) and LUN.
					 */

					if (message & 0x80) {
						DPRINTK (PHASE_MSGIN, "scsi%d : IDENTIFY message received from id %d, lun %d.\n", hostno, target, message & 7);
					} else {
						/*
						 *      We should go into a
						 *	MESSAGE OUT phase, and
						 *	send  a MESSAGE_REJECT
						 *      if we run into a message 
						 *	that we don't like.  The
						 *	seagate driver needs 
						 *	some serious 
						 *	restructuring first
						 *	though.
						 */
						DPRINTK (PHASE_MSGIN, "scsi%d : unknown message %d from target %d.\n", hostno, message, target);
					}
				}
				break;
			default:
				printk(KERN_ERR "scsi%d : unknown phase.\n", hostno);
				st0x_aborted = DID_ERROR;
			}	/* end of switch (status_read &  REQ_MASK) */
#ifdef SLOW_RATE
			/*
			 * I really don't care to deal with borken devices in
			 * each single byte transfer case (ie, message in,
			 * message out, status), so I'll do the wait here if 
			 * necessary.
			 */
			if(borken)
				borken_wait();
#endif

		}		/* if(status_read & STAT_REQ) ends */
	}			/* while(((status_read = STATUS)...) ends */

	DPRINTK(PHASE_DATAIN | PHASE_DATAOUT | PHASE_EXIT, "scsi%d : Transfered %d bytes\n", hostno, transfered);

#if (DEBUG & PHASE_EXIT)
#if 0				/* Doesn't work for scatter/gather */
	printk("Buffer : \n");
	for(i = 0; i < 20; ++i)
		printk("%02x  ", ((unsigned char *) data)[i]);	/* WDE mod */
	printk("\n");
#endif
	printk("scsi%d : status = ", hostno);
	scsi_print_status(status);
	printk(" message = %02x\n", message);
#endif

	/* We shouldn't reach this until *after* BSY has been deasserted */

#ifdef LINKED
	else
	{
		/*
		 * Fix the message byte so that unsuspecting high level drivers
		 * don't puke when they see a LINKED COMMAND message in place of
		 * the COMMAND COMPLETE they may be expecting.  Shouldn't be
		 * necessary, but it's better to be on the safe side.
		 *
		 * A non LINKED* message byte will indicate that the command
		 * completed, and we are now disconnected.
		 */

		switch (message) {
		case LINKED_CMD_COMPLETE:
		case LINKED_FLG_CMD_COMPLETE:
			message = COMMAND_COMPLETE;
			linked_target = current_target;
			linked_lun = current_lun;
			linked_connected = 1;
			DPRINTK (DEBUG_LINKED, "scsi%d : keeping I_T_L nexus established for linked command.\n", hostno);
			/* We also will need to adjust status to accommodate intermediate
			   conditions. */
			if ((status == INTERMEDIATE_GOOD) || (status == INTERMEDIATE_C_GOOD))
				status = GOOD;
			break;
			/*
			 * We should also handle what are "normal" termination
			 * messages here (ABORT, BUS_DEVICE_RESET?, and
			 * COMMAND_COMPLETE individually, and flake if things
			 * aren't right.
			 */
		default:
			DPRINTK (DEBUG_LINKED, "scsi%d : closing I_T_L nexus.\n", hostno);
			linked_connected = 0;
		}
	}
#endif	/* LINKED */

	if (should_reconnect) {
		DPRINTK (PHASE_RESELECT, "scsi%d : exiting seagate_st0x_queue_command() with reconnect enabled.\n", hostno);
		WRITE_CONTROL (BASE_CMD | CMD_INTR);
	} else
		WRITE_CONTROL (BASE_CMD);

	return retcode (st0x_aborted);
}				/* end of internal_command */

static int seagate_st0x_abort(struct scsi_cmnd * SCpnt)
{
	st0x_aborted = DID_ABORT;
	return SUCCESS;
}

#undef ULOOP
#undef TIMEOUT

/*
 * the seagate_st0x_reset function resets the SCSI bus 
 *
 * May be called with SCpnt = NULL
 */

static int seagate_st0x_bus_reset(struct scsi_cmnd * SCpnt)
{
	/* No timeouts - this command is going to fail because it was reset. */
	DANY ("scsi%d: Reseting bus... ", hostno);

	/* assert  RESET signal on SCSI bus.  */
	WRITE_CONTROL (BASE_CMD | CMD_RST);

	mdelay (20);

	WRITE_CONTROL (BASE_CMD);
	st0x_aborted = DID_RESET;

	DANY ("done.\n");
	return SUCCESS;
}

static int seagate_st0x_release(struct Scsi_Host *shost)
{
	if (shost->irq)
		free_irq(shost->irq, shost);
	release_region(shost->io_port, shost->n_io_port);
	return 0;
}

static struct scsi_host_template driver_template = {
	.detect         	= seagate_st0x_detect,
	.release        	= seagate_st0x_release,
	.info           	= seagate_st0x_info,
	.queuecommand   	= seagate_st0x_queue_command,
	.eh_abort_handler	= seagate_st0x_abort,
	.eh_bus_reset_handler	= seagate_st0x_bus_reset,
	.can_queue      	= 1,
	.this_id        	= 7,
	.sg_tablesize   	= SG_ALL,
	.cmd_per_lun    	= 1,
	.use_clustering		= DISABLE_CLUSTERING,
};
#include "scsi_module.c"