-
Notifications
You must be signed in to change notification settings - Fork 53.3k
/
wd33c93.c
2077 lines (1815 loc) · 60.8 KB
/
wd33c93.c
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
/*
* Copyright (c) 1996 John Shifflett, GeoLog Consulting
* john@geolog.com
* jshiffle@netcom.com
*
* 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.
*/
/*
* Drew Eckhardt's excellent 'Generic NCR5380' sources from Linux-PC
* provided much of the inspiration and some of the code for this
* driver. Everything I know about Amiga DMA was gleaned from careful
* reading of Hamish Mcdonald's original wd33c93 driver; in fact, I
* borrowed shamelessly from all over that source. Thanks Hamish!
*
* _This_ driver is (I feel) an improvement over the old one in
* several respects:
*
* - Target Disconnection/Reconnection is now supported. Any
* system with more than one device active on the SCSI bus
* will benefit from this. The driver defaults to what I
* call 'adaptive disconnect' - meaning that each command
* is evaluated individually as to whether or not it should
* be run with the option to disconnect/reselect (if the
* device chooses), or as a "SCSI-bus-hog".
*
* - Synchronous data transfers are now supported. Because of
* a few devices that choke after telling the driver that
* they can do sync transfers, we don't automatically use
* this faster protocol - it can be enabled via the command-
* line on a device-by-device basis.
*
* - Runtime operating parameters can now be specified through
* the 'amiboot' or the 'insmod' command line. For amiboot do:
* "amiboot [usual stuff] wd33c93=blah,blah,blah"
* The defaults should be good for most people. See the comment
* for 'setup_strings' below for more details.
*
* - The old driver relied exclusively on what the Western Digital
* docs call "Combination Level 2 Commands", which are a great
* idea in that the CPU is relieved of a lot of interrupt
* overhead. However, by accepting a certain (user-settable)
* amount of additional interrupts, this driver achieves
* better control over the SCSI bus, and data transfers are
* almost as fast while being much easier to define, track,
* and debug.
*
*
* TODO:
* more speed. linked commands.
*
*
* People with bug reports, wish-lists, complaints, comments,
* or improvements are asked to pah-leeez email me (John Shifflett)
* at john@geolog.com or jshiffle@netcom.com! I'm anxious to get
* this thing into as good a shape as possible, and I'm positive
* there are lots of lurking bugs and "Stupid Places".
*
* Updates:
*
* Added support for pre -A chips, which don't have advanced features
* and will generate CSR_RESEL rather than CSR_RESEL_AM.
* Richard Hirst <richard@sleepie.demon.co.uk> August 2000
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/version.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <asm/irq.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include "wd33c93.h"
#define WD33C93_VERSION "1.26"
#define WD33C93_DATE "22/Feb/2003"
MODULE_AUTHOR("John Shifflett");
MODULE_DESCRIPTION("Generic WD33C93 SCSI driver");
MODULE_LICENSE("GPL");
/*
* 'setup_strings' is a single string used to pass operating parameters and
* settings from the kernel/module command-line to the driver. 'setup_args[]'
* is an array of strings that define the compile-time default values for
* these settings. If Linux boots with an amiboot or insmod command-line,
* those settings are combined with 'setup_args[]'. Note that amiboot
* command-lines are prefixed with "wd33c93=" while insmod uses a
* "setup_strings=" prefix. The driver recognizes the following keywords
* (lower case required) and arguments:
*
* - nosync:bitmask -bitmask is a byte where the 1st 7 bits correspond with
* the 7 possible SCSI devices. Set a bit to negotiate for
* asynchronous transfers on that device. To maintain
* backwards compatibility, a command-line such as
* "wd33c93=255" will be automatically translated to
* "wd33c93=nosync:0xff".
* - nodma:x -x = 1 to disable DMA, x = 0 to enable it. Argument is
* optional - if not present, same as "nodma:1".
* - period:ns -ns is the minimum # of nanoseconds in a SCSI data transfer
* period. Default is 500; acceptable values are 250 - 1000.
* - disconnect:x -x = 0 to never allow disconnects, 2 to always allow them.
* x = 1 does 'adaptive' disconnects, which is the default
* and generally the best choice.
* - debug:x -If 'DEBUGGING_ON' is defined, x is a bit mask that causes
* various types of debug output to printed - see the DB_xxx
* defines in wd33c93.h
* - clock:x -x = clock input in MHz for WD33c93 chip. Normal values
* would be from 8 through 20. Default is 8.
* - next -No argument. Used to separate blocks of keywords when
* there's more than one host adapter in the system.
*
* Syntax Notes:
* - Numeric arguments can be decimal or the '0x' form of hex notation. There
* _must_ be a colon between a keyword and its numeric argument, with no
* spaces.
* - Keywords are separated by commas, no spaces, in the standard kernel
* command-line manner.
* - A keyword in the 'nth' comma-separated command-line member will overwrite
* the 'nth' element of setup_args[]. A blank command-line member (in
* other words, a comma with no preceding keyword) will _not_ overwrite
* the corresponding setup_args[] element.
* - If a keyword is used more than once, the first one applies to the first
* SCSI host found, the second to the second card, etc, unless the 'next'
* keyword is used to change the order.
*
* Some amiboot examples (for insmod, use 'setup_strings' instead of 'wd33c93'):
* - wd33c93=nosync:255
* - wd33c93=nodma
* - wd33c93=nodma:1
* - wd33c93=disconnect:2,nosync:0x08,period:250
* - wd33c93=debug:0x1c
*/
/* Normally, no defaults are specified */
static char *setup_args[] = { "", "", "", "", "", "", "", "", "" };
static char *setup_strings;
module_param(setup_strings, charp, 0);
static void wd33c93_execute(struct Scsi_Host *instance);
#ifdef CONFIG_WD33C93_PIO
static inline uchar
read_wd33c93(const wd33c93_regs regs, uchar reg_num)
{
uchar data;
outb(reg_num, regs.SASR);
data = inb(regs.SCMD);
return data;
}
static inline unsigned long
read_wd33c93_count(const wd33c93_regs regs)
{
unsigned long value;
outb(WD_TRANSFER_COUNT_MSB, regs.SASR);
value = inb(regs.SCMD) << 16;
value |= inb(regs.SCMD) << 8;
value |= inb(regs.SCMD);
return value;
}
static inline uchar
read_aux_stat(const wd33c93_regs regs)
{
return inb(regs.SASR);
}
static inline void
write_wd33c93(const wd33c93_regs regs, uchar reg_num, uchar value)
{
outb(reg_num, regs.SASR);
outb(value, regs.SCMD);
}
static inline void
write_wd33c93_count(const wd33c93_regs regs, unsigned long value)
{
outb(WD_TRANSFER_COUNT_MSB, regs.SASR);
outb((value >> 16) & 0xff, regs.SCMD);
outb((value >> 8) & 0xff, regs.SCMD);
outb( value & 0xff, regs.SCMD);
}
#define write_wd33c93_cmd(regs, cmd) \
write_wd33c93((regs), WD_COMMAND, (cmd))
static inline void
write_wd33c93_cdb(const wd33c93_regs regs, uint len, uchar cmnd[])
{
int i;
outb(WD_CDB_1, regs.SASR);
for (i=0; i<len; i++)
outb(cmnd[i], regs.SCMD);
}
#else /* CONFIG_WD33C93_PIO */
static inline uchar
read_wd33c93(const wd33c93_regs regs, uchar reg_num)
{
*regs.SASR = reg_num;
mb();
return (*regs.SCMD);
}
static unsigned long
read_wd33c93_count(const wd33c93_regs regs)
{
unsigned long value;
*regs.SASR = WD_TRANSFER_COUNT_MSB;
mb();
value = *regs.SCMD << 16;
value |= *regs.SCMD << 8;
value |= *regs.SCMD;
mb();
return value;
}
static inline uchar
read_aux_stat(const wd33c93_regs regs)
{
return *regs.SASR;
}
static inline void
write_wd33c93(const wd33c93_regs regs, uchar reg_num, uchar value)
{
*regs.SASR = reg_num;
mb();
*regs.SCMD = value;
mb();
}
static void
write_wd33c93_count(const wd33c93_regs regs, unsigned long value)
{
*regs.SASR = WD_TRANSFER_COUNT_MSB;
mb();
*regs.SCMD = value >> 16;
*regs.SCMD = value >> 8;
*regs.SCMD = value;
mb();
}
static inline void
write_wd33c93_cmd(const wd33c93_regs regs, uchar cmd)
{
*regs.SASR = WD_COMMAND;
mb();
*regs.SCMD = cmd;
mb();
}
static inline void
write_wd33c93_cdb(const wd33c93_regs regs, uint len, uchar cmnd[])
{
int i;
*regs.SASR = WD_CDB_1;
for (i = 0; i < len; i++)
*regs.SCMD = cmnd[i];
}
#endif /* CONFIG_WD33C93_PIO */
static inline uchar
read_1_byte(const wd33c93_regs regs)
{
uchar asr;
uchar x = 0;
write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO | 0x80);
do {
asr = read_aux_stat(regs);
if (asr & ASR_DBR)
x = read_wd33c93(regs, WD_DATA);
} while (!(asr & ASR_INT));
return x;
}
static struct sx_period sx_table[] = {
{1, 0x20},
{252, 0x20},
{376, 0x30},
{500, 0x40},
{624, 0x50},
{752, 0x60},
{876, 0x70},
{1000, 0x00},
{0, 0}
};
static int
round_period(unsigned int period)
{
int x;
for (x = 1; sx_table[x].period_ns; x++) {
if ((period <= sx_table[x - 0].period_ns) &&
(period > sx_table[x - 1].period_ns)) {
return x;
}
}
return 7;
}
static uchar
calc_sync_xfer(unsigned int period, unsigned int offset)
{
uchar result;
period *= 4; /* convert SDTR code to ns */
result = sx_table[round_period(period)].reg_value;
result |= (offset < OPTIMUM_SX_OFF) ? offset : OPTIMUM_SX_OFF;
return result;
}
int
wd33c93_queuecommand(struct scsi_cmnd *cmd,
void (*done)(struct scsi_cmnd *))
{
struct WD33C93_hostdata *hostdata;
struct scsi_cmnd *tmp;
hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
DB(DB_QUEUE_COMMAND,
printk("Q-%d-%02x-%ld( ", cmd->device->id, cmd->cmnd[0], cmd->pid))
/* Set up a few fields in the scsi_cmnd structure for our own use:
* - host_scribble is the pointer to the next cmd in the input queue
* - scsi_done points to the routine we call when a cmd is finished
* - result is what you'd expect
*/
cmd->host_scribble = NULL;
cmd->scsi_done = done;
cmd->result = 0;
/* We use the Scsi_Pointer structure that's included with each command
* as a scratchpad (as it's intended to be used!). The handy thing about
* the SCp.xxx fields is that they're always associated with a given
* cmd, and are preserved across disconnect-reselect. This means we
* can pretty much ignore SAVE_POINTERS and RESTORE_POINTERS messages
* if we keep all the critical pointers and counters in SCp:
* - SCp.ptr is the pointer into the RAM buffer
* - SCp.this_residual is the size of that buffer
* - SCp.buffer points to the current scatter-gather buffer
* - SCp.buffers_residual tells us how many S.G. buffers there are
* - SCp.have_data_in is not used
* - SCp.sent_command is not used
* - SCp.phase records this command's SRCID_ER bit setting
*/
if (cmd->use_sg) {
cmd->SCp.buffer = (struct scatterlist *) cmd->buffer;
cmd->SCp.buffers_residual = cmd->use_sg - 1;
cmd->SCp.ptr = page_address(cmd->SCp.buffer->page) +
cmd->SCp.buffer->offset;
cmd->SCp.this_residual = cmd->SCp.buffer->length;
} else {
cmd->SCp.buffer = NULL;
cmd->SCp.buffers_residual = 0;
cmd->SCp.ptr = (char *) cmd->request_buffer;
cmd->SCp.this_residual = cmd->request_bufflen;
}
/* WD docs state that at the conclusion of a "LEVEL2" command, the
* status byte can be retrieved from the LUN register. Apparently,
* this is the case only for *uninterrupted* LEVEL2 commands! If
* there are any unexpected phases entered, even if they are 100%
* legal (different devices may choose to do things differently),
* the LEVEL2 command sequence is exited. This often occurs prior
* to receiving the status byte, in which case the driver does a
* status phase interrupt and gets the status byte on its own.
* While such a command can then be "resumed" (ie restarted to
* finish up as a LEVEL2 command), the LUN register will NOT be
* a valid status byte at the command's conclusion, and we must
* use the byte obtained during the earlier interrupt. Here, we
* preset SCp.Status to an illegal value (0xff) so that when
* this command finally completes, we can tell where the actual
* status byte is stored.
*/
cmd->SCp.Status = ILLEGAL_STATUS_BYTE;
/*
* Add the cmd to the end of 'input_Q'. Note that REQUEST SENSE
* commands are added to the head of the queue so that the desired
* sense data is not lost before REQUEST_SENSE executes.
*/
spin_lock_irq(&hostdata->lock);
if (!(hostdata->input_Q) || (cmd->cmnd[0] == REQUEST_SENSE)) {
cmd->host_scribble = (uchar *) hostdata->input_Q;
hostdata->input_Q = cmd;
} else { /* find the end of the queue */
for (tmp = (struct scsi_cmnd *) hostdata->input_Q;
tmp->host_scribble;
tmp = (struct scsi_cmnd *) tmp->host_scribble) ;
tmp->host_scribble = (uchar *) cmd;
}
/* We know that there's at least one command in 'input_Q' now.
* Go see if any of them are runnable!
*/
wd33c93_execute(cmd->device->host);
DB(DB_QUEUE_COMMAND, printk(")Q-%ld ", cmd->pid))
spin_unlock_irq(&hostdata->lock);
return 0;
}
/*
* This routine attempts to start a scsi command. If the host_card is
* already connected, we give up immediately. Otherwise, look through
* the input_Q, using the first command we find that's intended
* for a currently non-busy target/lun.
*
* wd33c93_execute() is always called with interrupts disabled or from
* the wd33c93_intr itself, which means that a wd33c93 interrupt
* cannot occur while we are in here.
*/
static void
wd33c93_execute(struct Scsi_Host *instance)
{
struct WD33C93_hostdata *hostdata =
(struct WD33C93_hostdata *) instance->hostdata;
const wd33c93_regs regs = hostdata->regs;
struct scsi_cmnd *cmd, *prev;
DB(DB_EXECUTE, printk("EX("))
if (hostdata->selecting || hostdata->connected) {
DB(DB_EXECUTE, printk(")EX-0 "))
return;
}
/*
* Search through the input_Q for a command destined
* for an idle target/lun.
*/
cmd = (struct scsi_cmnd *) hostdata->input_Q;
prev = 0;
while (cmd) {
if (!(hostdata->busy[cmd->device->id] & (1 << cmd->device->lun)))
break;
prev = cmd;
cmd = (struct scsi_cmnd *) cmd->host_scribble;
}
/* quit if queue empty or all possible targets are busy */
if (!cmd) {
DB(DB_EXECUTE, printk(")EX-1 "))
return;
}
/* remove command from queue */
if (prev)
prev->host_scribble = cmd->host_scribble;
else
hostdata->input_Q = (struct scsi_cmnd *) cmd->host_scribble;
#ifdef PROC_STATISTICS
hostdata->cmd_cnt[cmd->device->id]++;
#endif
/*
* Start the selection process
*/
if (cmd->sc_data_direction == DMA_TO_DEVICE)
write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
else
write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id | DSTID_DPD);
/* Now we need to figure out whether or not this command is a good
* candidate for disconnect/reselect. We guess to the best of our
* ability, based on a set of hierarchical rules. When several
* devices are operating simultaneously, disconnects are usually
* an advantage. In a single device system, or if only 1 device
* is being accessed, transfers usually go faster if disconnects
* are not allowed:
*
* + Commands should NEVER disconnect if hostdata->disconnect =
* DIS_NEVER (this holds for tape drives also), and ALWAYS
* disconnect if hostdata->disconnect = DIS_ALWAYS.
* + Tape drive commands should always be allowed to disconnect.
* + Disconnect should be allowed if disconnected_Q isn't empty.
* + Commands should NOT disconnect if input_Q is empty.
* + Disconnect should be allowed if there are commands in input_Q
* for a different target/lun. In this case, the other commands
* should be made disconnect-able, if not already.
*
* I know, I know - this code would flunk me out of any
* "C Programming 101" class ever offered. But it's easy
* to change around and experiment with for now.
*/
cmd->SCp.phase = 0; /* assume no disconnect */
if (hostdata->disconnect == DIS_NEVER)
goto no;
if (hostdata->disconnect == DIS_ALWAYS)
goto yes;
if (cmd->device->type == 1) /* tape drive? */
goto yes;
if (hostdata->disconnected_Q) /* other commands disconnected? */
goto yes;
if (!(hostdata->input_Q)) /* input_Q empty? */
goto no;
for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
prev = (struct scsi_cmnd *) prev->host_scribble) {
if ((prev->device->id != cmd->device->id) ||
(prev->device->lun != cmd->device->lun)) {
for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
prev = (struct scsi_cmnd *) prev->host_scribble)
prev->SCp.phase = 1;
goto yes;
}
}
goto no;
yes:
cmd->SCp.phase = 1;
#ifdef PROC_STATISTICS
hostdata->disc_allowed_cnt[cmd->device->id]++;
#endif
no:
write_wd33c93(regs, WD_SOURCE_ID, ((cmd->SCp.phase) ? SRCID_ER : 0));
write_wd33c93(regs, WD_TARGET_LUN, cmd->device->lun);
write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
hostdata->sync_xfer[cmd->device->id]);
hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
if ((hostdata->level2 == L2_NONE) ||
(hostdata->sync_stat[cmd->device->id] == SS_UNSET)) {
/*
* Do a 'Select-With-ATN' command. This will end with
* one of the following interrupts:
* CSR_RESEL_AM: failure - can try again later.
* CSR_TIMEOUT: failure - give up.
* CSR_SELECT: success - proceed.
*/
hostdata->selecting = cmd;
/* Every target has its own synchronous transfer setting, kept in the
* sync_xfer array, and a corresponding status byte in sync_stat[].
* Each target's sync_stat[] entry is initialized to SX_UNSET, and its
* sync_xfer[] entry is initialized to the default/safe value. SS_UNSET
* means that the parameters are undetermined as yet, and that we
* need to send an SDTR message to this device after selection is
* complete: We set SS_FIRST to tell the interrupt routine to do so.
* If we've been asked not to try synchronous transfers on this
* target (and _all_ luns within it), we'll still send the SDTR message
* later, but at that time we'll negotiate for async by specifying a
* sync fifo depth of 0.
*/
if (hostdata->sync_stat[cmd->device->id] == SS_UNSET)
hostdata->sync_stat[cmd->device->id] = SS_FIRST;
hostdata->state = S_SELECTING;
write_wd33c93_count(regs, 0); /* guarantee a DATA_PHASE interrupt */
write_wd33c93_cmd(regs, WD_CMD_SEL_ATN);
} else {
/*
* Do a 'Select-With-ATN-Xfer' command. This will end with
* one of the following interrupts:
* CSR_RESEL_AM: failure - can try again later.
* CSR_TIMEOUT: failure - give up.
* anything else: success - proceed.
*/
hostdata->connected = cmd;
write_wd33c93(regs, WD_COMMAND_PHASE, 0);
/* copy command_descriptor_block into WD chip
* (take advantage of auto-incrementing)
*/
write_wd33c93_cdb(regs, cmd->cmd_len, cmd->cmnd);
/* The wd33c93 only knows about Group 0, 1, and 5 commands when
* it's doing a 'select-and-transfer'. To be safe, we write the
* size of the CDB into the OWN_ID register for every case. This
* way there won't be problems with vendor-unique, audio, etc.
*/
write_wd33c93(regs, WD_OWN_ID, cmd->cmd_len);
/* When doing a non-disconnect command with DMA, we can save
* ourselves a DATA phase interrupt later by setting everything
* up ahead of time.
*/
if ((cmd->SCp.phase == 0) && (hostdata->no_dma == 0)) {
if (hostdata->dma_setup(cmd,
(cmd->sc_data_direction == DMA_TO_DEVICE) ?
DATA_OUT_DIR : DATA_IN_DIR))
write_wd33c93_count(regs, 0); /* guarantee a DATA_PHASE interrupt */
else {
write_wd33c93_count(regs,
cmd->SCp.this_residual);
write_wd33c93(regs, WD_CONTROL,
CTRL_IDI | CTRL_EDI | CTRL_DMA);
hostdata->dma = D_DMA_RUNNING;
}
} else
write_wd33c93_count(regs, 0); /* guarantee a DATA_PHASE interrupt */
hostdata->state = S_RUNNING_LEVEL2;
write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
}
/*
* Since the SCSI bus can handle only 1 connection at a time,
* we get out of here now. If the selection fails, or when
* the command disconnects, we'll come back to this routine
* to search the input_Q again...
*/
DB(DB_EXECUTE,
printk("%s%ld)EX-2 ", (cmd->SCp.phase) ? "d:" : "", cmd->pid))
}
static void
transfer_pio(const wd33c93_regs regs, uchar * buf, int cnt,
int data_in_dir, struct WD33C93_hostdata *hostdata)
{
uchar asr;
DB(DB_TRANSFER,
printk("(%p,%d,%s:", buf, cnt, data_in_dir ? "in" : "out"))
write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
write_wd33c93_count(regs, cnt);
write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
if (data_in_dir) {
do {
asr = read_aux_stat(regs);
if (asr & ASR_DBR)
*buf++ = read_wd33c93(regs, WD_DATA);
} while (!(asr & ASR_INT));
} else {
do {
asr = read_aux_stat(regs);
if (asr & ASR_DBR)
write_wd33c93(regs, WD_DATA, *buf++);
} while (!(asr & ASR_INT));
}
/* Note: we are returning with the interrupt UN-cleared.
* Since (presumably) an entire I/O operation has
* completed, the bus phase is probably different, and
* the interrupt routine will discover this when it
* responds to the uncleared int.
*/
}
static void
transfer_bytes(const wd33c93_regs regs, struct scsi_cmnd *cmd,
int data_in_dir)
{
struct WD33C93_hostdata *hostdata;
unsigned long length;
hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
/* Normally, you'd expect 'this_residual' to be non-zero here.
* In a series of scatter-gather transfers, however, this
* routine will usually be called with 'this_residual' equal
* to 0 and 'buffers_residual' non-zero. This means that a
* previous transfer completed, clearing 'this_residual', and
* now we need to setup the next scatter-gather buffer as the
* source or destination for THIS transfer.
*/
if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
++cmd->SCp.buffer;
--cmd->SCp.buffers_residual;
cmd->SCp.this_residual = cmd->SCp.buffer->length;
cmd->SCp.ptr = page_address(cmd->SCp.buffer->page) +
cmd->SCp.buffer->offset;
}
write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
hostdata->sync_xfer[cmd->device->id]);
/* 'hostdata->no_dma' is TRUE if we don't even want to try DMA.
* Update 'this_residual' and 'ptr' after 'transfer_pio()' returns.
*/
if (hostdata->no_dma || hostdata->dma_setup(cmd, data_in_dir)) {
#ifdef PROC_STATISTICS
hostdata->pio_cnt++;
#endif
transfer_pio(regs, (uchar *) cmd->SCp.ptr,
cmd->SCp.this_residual, data_in_dir, hostdata);
length = cmd->SCp.this_residual;
cmd->SCp.this_residual = read_wd33c93_count(regs);
cmd->SCp.ptr += (length - cmd->SCp.this_residual);
}
/* We are able to do DMA (in fact, the Amiga hardware is
* already going!), so start up the wd33c93 in DMA mode.
* We set 'hostdata->dma' = D_DMA_RUNNING so that when the
* transfer completes and causes an interrupt, we're
* reminded to tell the Amiga to shut down its end. We'll
* postpone the updating of 'this_residual' and 'ptr'
* until then.
*/
else {
#ifdef PROC_STATISTICS
hostdata->dma_cnt++;
#endif
write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_DMA);
write_wd33c93_count(regs, cmd->SCp.this_residual);
if ((hostdata->level2 >= L2_DATA) ||
(hostdata->level2 == L2_BASIC && cmd->SCp.phase == 0)) {
write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
hostdata->state = S_RUNNING_LEVEL2;
} else
write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
hostdata->dma = D_DMA_RUNNING;
}
}
void
wd33c93_intr(struct Scsi_Host *instance)
{
struct WD33C93_hostdata *hostdata =
(struct WD33C93_hostdata *) instance->hostdata;
const wd33c93_regs regs = hostdata->regs;
struct scsi_cmnd *patch, *cmd;
uchar asr, sr, phs, id, lun, *ucp, msg;
unsigned long length, flags;
asr = read_aux_stat(regs);
if (!(asr & ASR_INT) || (asr & ASR_BSY))
return;
spin_lock_irqsave(&hostdata->lock, flags);
#ifdef PROC_STATISTICS
hostdata->int_cnt++;
#endif
cmd = (struct scsi_cmnd *) hostdata->connected; /* assume we're connected */
sr = read_wd33c93(regs, WD_SCSI_STATUS); /* clear the interrupt */
phs = read_wd33c93(regs, WD_COMMAND_PHASE);
DB(DB_INTR, printk("{%02x:%02x-", asr, sr))
/* After starting a DMA transfer, the next interrupt
* is guaranteed to be in response to completion of
* the transfer. Since the Amiga DMA hardware runs in
* in an open-ended fashion, it needs to be told when
* to stop; do that here if D_DMA_RUNNING is true.
* Also, we have to update 'this_residual' and 'ptr'
* based on the contents of the TRANSFER_COUNT register,
* in case the device decided to do an intermediate
* disconnect (a device may do this if it has to do a
* seek, or just to be nice and let other devices have
* some bus time during long transfers). After doing
* whatever is needed, we go on and service the WD3393
* interrupt normally.
*/
if (hostdata->dma == D_DMA_RUNNING) {
DB(DB_TRANSFER,
printk("[%p/%d:", cmd->SCp.ptr, cmd->SCp.this_residual))
hostdata->dma_stop(cmd->device->host, cmd, 1);
hostdata->dma = D_DMA_OFF;
length = cmd->SCp.this_residual;
cmd->SCp.this_residual = read_wd33c93_count(regs);
cmd->SCp.ptr += (length - cmd->SCp.this_residual);
DB(DB_TRANSFER,
printk("%p/%d]", cmd->SCp.ptr, cmd->SCp.this_residual))
}
/* Respond to the specific WD3393 interrupt - there are quite a few! */
switch (sr) {
case CSR_TIMEOUT:
DB(DB_INTR, printk("TIMEOUT"))
if (hostdata->state == S_RUNNING_LEVEL2)
hostdata->connected = NULL;
else {
cmd = (struct scsi_cmnd *) hostdata->selecting; /* get a valid cmd */
hostdata->selecting = NULL;
}
cmd->result = DID_NO_CONNECT << 16;
hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
hostdata->state = S_UNCONNECTED;
cmd->scsi_done(cmd);
/* From esp.c:
* There is a window of time within the scsi_done() path
* of execution where interrupts are turned back on full
* blast and left that way. During that time we could
* reconnect to a disconnected command, then we'd bomb
* out below. We could also end up executing two commands
* at _once_. ...just so you know why the restore_flags()
* is here...
*/
spin_unlock_irqrestore(&hostdata->lock, flags);
/* We are not connected to a target - check to see if there
* are commands waiting to be executed.
*/
wd33c93_execute(instance);
break;
/* Note: this interrupt should not occur in a LEVEL2 command */
case CSR_SELECT:
DB(DB_INTR, printk("SELECT"))
hostdata->connected = cmd =
(struct scsi_cmnd *) hostdata->selecting;
hostdata->selecting = NULL;
/* construct an IDENTIFY message with correct disconnect bit */
hostdata->outgoing_msg[0] = (0x80 | 0x00 | cmd->device->lun);
if (cmd->SCp.phase)
hostdata->outgoing_msg[0] |= 0x40;
if (hostdata->sync_stat[cmd->device->id] == SS_FIRST) {
#ifdef SYNC_DEBUG
printk(" sending SDTR ");
#endif
hostdata->sync_stat[cmd->device->id] = SS_WAITING;
/* Tack on a 2nd message to ask about synchronous transfers. If we've
* been asked to do only asynchronous transfers on this device, we
* request a fifo depth of 0, which is equivalent to async - should
* solve the problems some people have had with GVP's Guru ROM.
*/
hostdata->outgoing_msg[1] = EXTENDED_MESSAGE;
hostdata->outgoing_msg[2] = 3;
hostdata->outgoing_msg[3] = EXTENDED_SDTR;
if (hostdata->no_sync & (1 << cmd->device->id)) {
hostdata->outgoing_msg[4] =
hostdata->default_sx_per / 4;
hostdata->outgoing_msg[5] = 0;
} else {
hostdata->outgoing_msg[4] = OPTIMUM_SX_PER / 4;
hostdata->outgoing_msg[5] = OPTIMUM_SX_OFF;
}
hostdata->outgoing_len = 6;
} else
hostdata->outgoing_len = 1;
hostdata->state = S_CONNECTED;
spin_unlock_irqrestore(&hostdata->lock, flags);
break;
case CSR_XFER_DONE | PHS_DATA_IN:
case CSR_UNEXP | PHS_DATA_IN:
case CSR_SRV_REQ | PHS_DATA_IN:
DB(DB_INTR,
printk("IN-%d.%d", cmd->SCp.this_residual,
cmd->SCp.buffers_residual))
transfer_bytes(regs, cmd, DATA_IN_DIR);
if (hostdata->state != S_RUNNING_LEVEL2)
hostdata->state = S_CONNECTED;
spin_unlock_irqrestore(&hostdata->lock, flags);
break;
case CSR_XFER_DONE | PHS_DATA_OUT:
case CSR_UNEXP | PHS_DATA_OUT:
case CSR_SRV_REQ | PHS_DATA_OUT:
DB(DB_INTR,
printk("OUT-%d.%d", cmd->SCp.this_residual,
cmd->SCp.buffers_residual))
transfer_bytes(regs, cmd, DATA_OUT_DIR);
if (hostdata->state != S_RUNNING_LEVEL2)
hostdata->state = S_CONNECTED;
spin_unlock_irqrestore(&hostdata->lock, flags);
break;
/* Note: this interrupt should not occur in a LEVEL2 command */
case CSR_XFER_DONE | PHS_COMMAND:
case CSR_UNEXP | PHS_COMMAND:
case CSR_SRV_REQ | PHS_COMMAND:
DB(DB_INTR, printk("CMND-%02x,%ld", cmd->cmnd[0], cmd->pid))
transfer_pio(regs, cmd->cmnd, cmd->cmd_len, DATA_OUT_DIR,
hostdata);
hostdata->state = S_CONNECTED;
spin_unlock_irqrestore(&hostdata->lock, flags);
break;
case CSR_XFER_DONE | PHS_STATUS:
case CSR_UNEXP | PHS_STATUS:
case CSR_SRV_REQ | PHS_STATUS:
DB(DB_INTR, printk("STATUS="))
cmd->SCp.Status = read_1_byte(regs);
DB(DB_INTR, printk("%02x", cmd->SCp.Status))
if (hostdata->level2 >= L2_BASIC) {
sr = read_wd33c93(regs, WD_SCSI_STATUS); /* clear interrupt */
hostdata->state = S_RUNNING_LEVEL2;
write_wd33c93(regs, WD_COMMAND_PHASE, 0x50);
write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
} else {
hostdata->state = S_CONNECTED;
}
spin_unlock_irqrestore(&hostdata->lock, flags);
break;
case CSR_XFER_DONE | PHS_MESS_IN:
case CSR_UNEXP | PHS_MESS_IN:
case CSR_SRV_REQ | PHS_MESS_IN:
DB(DB_INTR, printk("MSG_IN="))
msg = read_1_byte(regs);
sr = read_wd33c93(regs, WD_SCSI_STATUS); /* clear interrupt */
hostdata->incoming_msg[hostdata->incoming_ptr] = msg;
if (hostdata->incoming_msg[0] == EXTENDED_MESSAGE)
msg = EXTENDED_MESSAGE;
else
hostdata->incoming_ptr = 0;
cmd->SCp.Message = msg;
switch (msg) {
case COMMAND_COMPLETE:
DB(DB_INTR, printk("CCMP-%ld", cmd->pid))
write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
hostdata->state = S_PRE_CMP_DISC;
break;
case SAVE_POINTERS:
DB(DB_INTR, printk("SDP"))
write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
hostdata->state = S_CONNECTED;
break;
case RESTORE_POINTERS:
DB(DB_INTR, printk("RDP"))
if (hostdata->level2 >= L2_BASIC) {
write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
hostdata->state = S_RUNNING_LEVEL2;
} else {
write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
hostdata->state = S_CONNECTED;
}
break;
case DISCONNECT:
DB(DB_INTR, printk("DIS"))
cmd->device->disconnect = 1;
write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
hostdata->state = S_PRE_TMP_DISC;
break;
case MESSAGE_REJECT: