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*/
1 /*
2 * @(#)aha274x.c 1.29 94/10/29 jda
3 *
4 * Adaptec 274x device driver for Linux.
5 * Copyright (c) 1994 The University of Calgary Department of Computer Science.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 *
21 * Sources include the Adaptec 1740 driver (aha1740.c), the
22 * Ultrastor 24F driver (ultrastor.c), various Linux kernel
23 * source, the Adaptec EISA config file (!adp7771.cfg), the
24 * Adaptec AHA-2740A Series User's Guide, the Linux Kernel
25 * Hacker's Guide, Writing a SCSI Device Driver for Linux,
26 * the Adaptec 1542 driver (aha1542.c), the Adaptec EISA
27 * overlay file (adp7770.ovl), the Adaptec AHA-2740 Series
28 * Technical Reference Manual, the Adaptec AIC-7770 Data
29 * Book, the ANSI SCSI specification, the ANSI SCSI-2
30 * specification (draft 10c), ...
31 *
32 * On a twin-bus adapter card, channel B is ignored. Rationale:
33 * it would greatly complicate the sequencer and host driver code,
34 * and both busses are multiplexed on to the EISA bus anyway. So
35 * I don't really see any technical advantage to supporting both.
36 *
37 * As well, multiple adapter card using the same IRQ level are
38 * not supported. It doesn't make sense to configure the cards
39 * this way from a performance standpoint. Not to mention that
40 * the kernel would have to support two devices per registered IRQ.
41 */
42
43 #include <stdarg.h>
44 #include <asm/io.h>
45 #include <linux/string.h>
46 #include <linux/kernel.h>
47 #include <linux/ioport.h>
48 #include <linux/delay.h>
49
50 #include "../block/blk.h"
51 #include "sd.h"
52 #include "scsi.h"
53 #include "hosts.h"
54 #include "aha274x.h"
55
56 /*
57 * There should be a specific return value for this in scsi.h, but
58 * it seems that most drivers ignore it.
59 */
60 #define DID_UNDERFLOW DID_ERROR
61
62 /* EISA stuff */
63
64 #define MINEISA 1
65 #define MAXEISA 15
66 #define SLOTBASE(x) ((x) << 12)
67
68 #define MAXIRQ 15
69
70 /* AIC-7770 offset definitions */
71
72 #define O_MINREG(x) ((x) + 0xc00) /* i/o range to reserve */
73 #define O_MAXREG(x) ((x) + 0xcbf)
74
75 #define O_SCSISEQ(x) ((x) + 0xc00) /* scsi sequence control */
76 #define O_SCSISIGI(x) ((x) + 0xc03) /* scsi control signal read */
77 #define O_SCSISIGO(x) ((x) + 0xc03) /* scsi control signal write */
78 #define O_SCSIID(x) ((x) + 0xc05) /* scsi id */
79 #define O_SSTAT0(x) ((x) + 0xc0b) /* scsi status register 0 */
80 #define O_CLRSINT1(x) ((x) + 0xc0c) /* clear scsi interrupt 1 */
81 #define O_SSTAT1(x) ((x) + 0xc0c) /* scsi status register 1 */
82 #define O_SELID(x) ((x) + 0xc19) /* [re]selection id */
83 #define O_SBLKCTL(x) ((x) + 0xc1f) /* scsi block control */
84 #define O_SEQCTL(x) ((x) + 0xc60) /* sequencer control */
85 #define O_SEQRAM(x) ((x) + 0xc61) /* sequencer ram data */
86 #define O_SEQADDR(x) ((x) + 0xc62) /* sequencer address (W) */
87 #define O_BIDx(x) ((x) + 0xc80) /* board id */
88 #define O_BCTL(x) ((x) + 0xc84) /* board control */
89 #define O_HCNTRL(x) ((x) + 0xc87) /* host control */
90 #define O_SCBPTR(x) ((x) + 0xc90) /* scb pointer */
91 #define O_INTSTAT(x) ((x) + 0xc91) /* interrupt status */
92 #define O_ERROR(x) ((x) + 0xc92) /* hard error */
93 #define O_CLRINT(x) ((x) + 0xc92) /* clear interrupt status */
94 #define O_SCBCNT(x) ((x) + 0xc9a) /* scb auto increment */
95 #define O_QINFIFO(x) ((x) + 0xc9b) /* queue in fifo */
96 #define O_QINCNT(x) ((x) + 0xc9c) /* queue in count */
97 #define O_QOUTFIFO(x) ((x) + 0xc9d) /* queue out fifo */
98 #define O_QOUTCNT(x) ((x) + 0xc9e) /* queue out count */
99 #define O_SCBARRAY(x) ((x) + 0xca0) /* scb array start */
100
101 /* host adapter offset definitions */
102
103 #define HA_REJBYTE(x) ((x) + 0xc31) /* 1st message in byte */
104 #define HA_MSG_FLAGS(x) ((x) + 0xc35) /* outgoing message flag */
105 #define HA_MSG_LEN(x) ((x) + 0xc36) /* outgoing message length */
106 #define HA_MSG_START(x) ((x) + 0xc37) /* outgoing message body */
107 #define HA_ARG_1(x) ((x) + 0xc4c) /* sdtr <-> rate parameters */
108 #define HA_ARG_2(x) ((x) + 0xc4d)
109 #define HA_RETURN_1(x) ((x) + 0xc4c)
110 #define HA_RETURN_2(x) ((x) + 0xc4d)
111 #define HA_SIGSTATE(x) ((x) + 0xc4e) /* value in SCSISIGO */
112 #define HA_NEEDSDTR(x) ((x) + 0xc4f) /* synchronous negotiation? */
113
114 #define HA_SCSICONF(x) ((x) + 0xc5a) /* SCSI config register */
115 #define HA_INTDEF(x) ((x) + 0xc5c) /* interrupt def'n register */
116 #define HA_HOSTCONF(x) ((x) + 0xc5d) /* host config def'n register */
117
118 /* debugging code */
119
120 #define AHA274X_DEBUG
121
122 /*
123 * If a parity error occurs during a data transfer phase, run the
124 * command to completion - it's easier that way - making a note
125 * of the error condition in this location. This then will modify
126 * a DID_OK status into a DID_PARITY one for the higher-level SCSI
127 * code.
128 */
129 #define aha274x_parity(cmd) ((cmd)->SCp.Status)
130
131 /*
132 * Since the sequencer code DMAs the scatter-gather structures
133 * directly from memory, we use this macro to assert that the
134 * kernel structure hasn't changed.
135 */
136 #define SG_STRUCT_CHECK(sg) \
137 ((char *)&(sg).address - (char *)&(sg) != 0 || \
138 (char *)&(sg).length - (char *)&(sg) != 8 || \
139 sizeof((sg).address) != 4 || \
140 sizeof((sg).length) != 4 || \
141 sizeof(sg) != 12)
142
143 /*
144 * "Static" structures. Note that these are NOT initialized
145 * to zero inside the kernel - we have to initialize them all
146 * explicitly.
147 *
148 * We support a maximum of one adapter card per IRQ level (see the
149 * rationale for this above). On an interrupt, use the IRQ as an
150 * index into aha274x_boards[] to locate the card information.
151 */
152 static struct Scsi_Host *aha274x_boards[MAXIRQ + 1];
153
154 struct aha274x_host {
155 int base; /* card base address */
156 int startup; /* intr type check */
157 volatile int unpause; /* value for HCNTRL */
158 volatile Scsi_Cmnd *SCB_array[AHA274X_MAXSCB]; /* active commands */
159 };
160
161 struct aha274x_scb {
162 unsigned char control;
163 unsigned char target_channel_lun; /* 4/1/3 bits */
164 unsigned char SG_segment_count;
165 unsigned char SG_list_pointer[4];
166 unsigned char SCSI_cmd_pointer[4];
167 unsigned char SCSI_cmd_length;
168 unsigned char RESERVED[2]; /* must be zero */
169 unsigned char target_status;
170 unsigned char residual_data_count[3];
171 unsigned char residual_SG_segment_count;
172 unsigned char data_pointer[4];
173 unsigned char data_count[3];
174 #if 0
175 /*
176 * No real point in transferring this to the
177 * SCB registers.
178 */
179 unsigned char RESERVED[6];
180 #endif
181 };
182
183 /*
184 * NB. This table MUST be ordered shortest period first.
185 */
186 static struct {
187 short period;
188 short rate;
189 char *english;
190 } aha274x_synctab[] = {
191 100, 0, "10.0",
192 125, 1, "8.0",
193 150, 2, "6.67",
194 175, 3, "5.7",
195 200, 4, "5.0",
196 225, 5, "4.4",
197 250, 6, "4.0",
198 275, 7, "3.6"
199 };
200
201 static int aha274x_synctab_max =
202 sizeof(aha274x_synctab) / sizeof(aha274x_synctab[0]);
203
204 enum aha_type {
205 T_NONE,
206 T_274X,
207 T_284X,
208 T_MAX
209 };
210
211 #ifdef AHA274X_DEBUG
212
213 extern int vsprintf(char *, const char *, va_list);
214
215 static
216 void debug(const char *fmt, ...)
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217 {
218 va_list ap;
219 char buf[256];
220
221 va_start(ap, fmt);
222 vsprintf(buf, fmt, ap);
223 printk(buf);
224 va_end(ap);
225 }
226
227 static
228 void debug_config(enum aha_type type, int base)
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*/
229 {
230 int ioport2, ioport3, ioport4;
231
232 static char *BRT[T_MAX][16] = {
233 { }, /* T_NONE */
234 {
235 "2", "???", "???", "12", /* T_274X */
236 "???", "???", "???", "28",
237 "???", "???", "???", "44",
238 "???", "???", "???", "60"
239 },
240 {
241 "2", "4", "8", "12", /* T_284X */
242 "16", "20", "24", "28",
243 "32", "36", "40", "44",
244 "48", "52", "56", "60"
245 }
246 };
247 static int DFT[4] = {
248 0, 50, 75, 100
249 };
250 static int SST[4] = {
251 256, 128, 64, 32
252 };
253
254 ioport2 = inb(HA_HOSTCONF(base));
255 ioport3 = inb(HA_SCSICONF(base));
256 ioport4 = inb(HA_INTDEF(base));
257
258 if (type == T_284X)
259 printk("AHA284X AT SLOT %d:\n", base >> 12);
260 else
261 printk("AHA274X AT EISA SLOT %d:\n", base >> 12);
262
263 printk(" irq %d\n"
264 " bus release time %s bclks\n"
265 " data fifo threshold %d%%\n",
266 ioport4 & 0xf,
267 BRT[type][(ioport2 >> 2) & 0xf],
268 DFT[(ioport2 >> 6) & 0x3]);
269
270 printk(" SCSI CHANNEL A:\n"
271 " scsi id %d\n"
272 " scsi bus parity check %sabled\n"
273 " scsi selection timeout %d ms\n"
274 " scsi bus reset at power-on %sabled\n",
275 ioport3 & 0x7,
276 (ioport3 & 0x20) ? "en" : "dis",
277 SST[(ioport3 >> 3) & 0x3],
278 (ioport3 & 0x40) ? "en" : "dis");
279
280 if (type == T_274X) {
281 printk(" scsi bus termination %sabled\n",
282 (ioport3 & 0x80) ? "en" : "dis");
283 }
284 }
285
286 static
287 void debug_rate(int base, int rate)
/* */
288 {
289 int target = inb(O_SCSIID(base)) >> 4;
290
291 if (rate) {
292 printk("aha274x: target %d now synchronous at %sMb/s\n",
293 target,
294 aha274x_synctab[(rate >> 4) & 0x7].english);
295 } else {
296 printk("aha274x: target %d using asynchronous mode\n",
297 target);
298 }
299 }
300
301 #else
302
303 # define debug(fmt, args...)
304 # define debug_config(x)
305 # define debug_rate(x,y)
306
307 #endif AHA274X_DEBUG
308
309 /*
310 * XXX - these options apply unilaterally to _all_ 274x/284x
311 * cards in the system. This should be fixed, but then,
312 * does anyone really have more than one in a machine?
313 */
314 static int aha274x_extended = 0; /* extended translation on? */
315
316 void aha274x_setup(char *s, int *dummy)
/* */
317 {
318 int i;
319 char *p;
320
321 static struct {
322 char *name;
323 int *flag;
324 } options[] = {
325 "extended", &aha274x_extended,
326 NULL
327 };
328
329 for (p = strtok(s, ","); p; p = strtok(NULL, ",")) {
330 for (i = 0; options[i].name; i++)
331 if (!strcmp(options[i].name, p))
332 *(options[i].flag) = !0;
333 }
334 }
335
336 static
337 void aha274x_getscb(int base, struct aha274x_scb *scb)
/* */
338 {
339 /*
340 * This is almost identical to aha274x_putscb().
341 */
342 outb(0x80, O_SCBCNT(base)); /* SCBAUTO */
343
344 asm volatile("cld\n\t"
345 "rep\n\t"
346 "insb"
347 : /* no output */
348 :"D" (scb), "c" (sizeof(*scb)), "d" (O_SCBARRAY(base))
349 :"di", "cx", "dx");
350
351 outb(0, O_SCBCNT(base));
352 }
353
354 /*
355 * How much data should be transferred for this SCSI command? Stop
356 * at segment sg_last if it's a scatter-gather command so we can
357 * compute underflow easily.
358 */
359 static
360 unsigned aha274x_length(Scsi_Cmnd *cmd, int sg_last)
/* */
361 {
362 int i, segments;
363 unsigned length;
364 struct scatterlist *sg;
365
366 segments = cmd->use_sg - sg_last;
367 sg = (struct scatterlist *)cmd->buffer;
368
369 if (cmd->use_sg) {
370 for (i = length = 0;
371 i < cmd->use_sg && i < segments;
372 i++)
373 {
374 length += sg[i].length;
375 }
376 } else
377 length = cmd->request_bufflen;
378
379 return(length);
380 }
381
382 static
383 void aha274x_sg_check(Scsi_Cmnd *cmd)
/* */
384 {
385 int i;
386 struct scatterlist *sg = (struct scatterlist *)cmd->buffer;
387
388 if (cmd->use_sg) {
389 for (i = 0; i < cmd->use_sg; i++)
390 if ((unsigned)sg[i].length > 0xffff)
391 panic("aha274x_sg_check: s/g segment > 64k\n");
392 }
393 }
394
395 static
396 void aha274x_to_scsirate(unsigned char *rate,
/* */
397 unsigned char transfer,
398 unsigned char offset)
399 {
400 int i;
401
402 transfer *= 4;
403
404 for (i = 0; i < aha274x_synctab_max-1; i++) {
405
406 if (transfer == aha274x_synctab[i].period) {
407 *rate = (aha274x_synctab[i].rate << 4) | (offset & 0xf);
408 return;
409 }
410
411 if (transfer > aha274x_synctab[i].period &&
412 transfer < aha274x_synctab[i+1].period)
413 {
414 *rate = (aha274x_synctab[i+1].rate << 4) |
415 (offset & 0xf);
416 return;
417 }
418 }
419 *rate = 0;
420 }
421
422 /*
423 * Pause the sequencer and wait for it to actually stop - this
424 * is important since the sequencer can disable pausing for critical
425 * sections.
426 */
427 #define PAUSE_SEQUENCER(p) \
428 do { \
429 outb(0xe, O_HCNTRL(p->base)); /* IRQMS|PAUSE|INTEN */ \
430 \
431 while ((inb(O_HCNTRL(p->base)) & 0x4) == 0) \
432 ; \
433 } while (0)
434
435 /*
436 * Unpause the sequencer. Unremarkable, yet done often enough to
437 * warrant an easy way to do it.
438 */
439 #define UNPAUSE_SEQUENCER(p) \
440 outb(p->unpause, O_HCNTRL(p->base)) /* IRQMS|INTEN */
441
442 /*
443 * See comments in aha274x_loadram() wrt this.
444 */
445 #define RESTART_SEQUENCER(p) \
446 do { \
447 do { \
448 outb(0x2, O_SEQCTL(p->base)); \
449 } while (inw(O_SEQADDR(p->base)) != 0); \
450 \
451 UNPAUSE_SEQUENCER(p); \
452 } while (0)
453
454 /*
455 * Since we declared this using SA_INTERRUPT, interrupts should
456 * be disabled all through this function unless we say otherwise.
457 */
458 static
459 void aha274x_isr(int irq)
/* */
460 {
461 int base, intstat;
462 struct aha274x_host *p;
463
464 p = (struct aha274x_host *)aha274x_boards[irq]->hostdata;
465 base = p->base;
466
467 /*
468 * Check the startup flag - if no commands have been queued,
469 * we probably have the interrupt type set wrong. Reverse
470 * the stored value and the active one in the host control
471 * register.
472 */
473 if (p->startup) {
474 p->unpause ^= 0x8;
475 outb(inb(O_HCNTRL(p->base)) ^ 0x8, O_HCNTRL(p->base));
476 return;
477 }
478
479 /*
480 * Handle all the interrupt sources - especially for SCSI
481 * interrupts, we won't get a second chance at them.
482 */
483 intstat = inb(O_INTSTAT(base));
484
485 if (intstat & 0x8) { /* BRKADRINT */
486
487 panic("aha274x_isr: brkadrint, error = 0x%x, seqaddr = 0x%x\n",
488 inb(O_ERROR(base)), inw(O_SEQADDR(base)));
489 }
490
491 if (intstat & 0x4) { /* SCSIINT */
492
493 int scbptr = inb(O_SCBPTR(base));
494 int status = inb(O_SSTAT1(base));
495 Scsi_Cmnd *cmd;
496
497 cmd = (Scsi_Cmnd *)p->SCB_array[scbptr];
498 if (!cmd) {
499 printk("aha274x_isr: no command for scb (scsiint)\n");
500 /*
501 * Turn off the interrupt and set status
502 * to zero, so that it falls through the
503 * reset of the SCSIINT code.
504 */
505 outb(status, O_CLRSINT1(base));
506 UNPAUSE_SEQUENCER(p);
507 outb(0x4, O_CLRINT(base)); /* undocumented */
508 status = 0;
509 }
510 p->SCB_array[scbptr] = NULL;
511
512 /*
513 * Only the SCSI Status 1 register has information
514 * about exceptional conditions that we'd have a
515 * SCSIINT about; anything in SSTAT0 will be handled
516 * by the sequencer. Note that there can be multiple
517 * bits set.
518 */
519 if (status & 0x80) { /* SELTO */
520 /*
521 * Hardware selection timer has expired. Turn
522 * off SCSI selection sequence.
523 */
524 outb(0, O_SCSISEQ(base));
525 cmd->result = DID_TIME_OUT << 16;
526
527 /*
528 * If there's an active message, it belongs to the
529 * command that is getting punted - remove it.
530 */
531 outb(0, HA_MSG_FLAGS(base));
532
533 /*
534 * Shut off the offending interrupt sources, reset
535 * the sequencer address to zero and unpause it,
536 * then call the high-level SCSI completion routine.
537 *
538 * WARNING! This is a magic sequence! After many
539 * hours of guesswork, turning off the SCSI interrupts
540 * in CLRSINT? does NOT clear the SCSIINT bit in
541 * INTSTAT. By writing to the (undocumented, unused
542 * according to the AIC-7770 manual) third bit of
543 * CLRINT, you can clear INTSTAT. But, if you do it
544 * while the sequencer is paused, you get a BRKADRINT
545 * with an Illegal Host Address status, so the
546 * sequencer has to be restarted first.
547 */
548 outb(0x80, O_CLRSINT1(base)); /* CLRSELTIMO */
549 RESTART_SEQUENCER(p);
550
551 outb(0x4, O_CLRINT(base)); /* undocumented */
552 cmd->scsi_done(cmd);
553 }
554
555 if (status & 0x4) { /* SCSIPERR */
556 /*
557 * A parity error has occurred during a data
558 * transfer phase. Flag it and continue.
559 */
560 printk("aha274x: parity error on target %d, lun %d\n",
561 cmd->target,
562 cmd->lun);
563 aha274x_parity(cmd) = DID_PARITY;
564
565 /*
566 * Clear interrupt and resume as above.
567 */
568 outb(0x4, O_CLRSINT1(base)); /* CLRSCSIPERR */
569 UNPAUSE_SEQUENCER(p);
570
571 outb(0x4, O_CLRINT(base)); /* undocumented */
572 }
573
574 if ((status & (0x8|0x4)) == 0 && status) {
575 /*
576 * We don't know what's going on. Turn off the
577 * interrupt source and try to continue.
578 */
579 printk("aha274x_isr: sstat1 = 0x%x\n", status);
580 outb(status, O_CLRSINT1(base));
581 UNPAUSE_SEQUENCER(p);
582 outb(0x4, O_CLRINT(base)); /* undocumented */
583 }
584 }
585
586 if (intstat & 0x2) { /* CMDCMPLT */
587
588 int complete, old_scbptr;
589 struct aha274x_scb scb;
590 unsigned actual;
591 Scsi_Cmnd *cmd;
592
593 /*
594 * The sequencer will continue running when it
595 * issues this interrupt. There may be >1 commands
596 * finished, so loop until we've processed them all.
597 */
598 do {
599 complete = inb(O_QOUTFIFO(base));
600
601 cmd = (Scsi_Cmnd *)p->SCB_array[complete];
602 if (!cmd) {
603 printk("aha274x warning: "
604 "no command for scb (cmdcmplt)\n");
605 continue;
606 }
607 p->SCB_array[complete] = NULL;
608
609 PAUSE_SEQUENCER(p);
610
611 /*
612 * After pausing the sequencer (and waiting
613 * for it to stop), save its SCB pointer, then
614 * write in our completed one and read the SCB
615 * registers. Afterwards, restore the saved
616 * pointer, unpause the sequencer and call the
617 * higher-level completion function - unpause
618 * first since we have no idea how long done()
619 * will take.
620 */
621 old_scbptr = inb(O_SCBPTR(base));
622 outb(complete, O_SCBPTR(base));
623
624 aha274x_getscb(base, &scb);
625 outb(old_scbptr, O_SCBPTR(base));
626
627 UNPAUSE_SEQUENCER(p);
628
629 cmd->result = scb.target_status |
630 (aha274x_parity(cmd) << 16);
631
632 /*
633 * Did we underflow? At this time, there's only
634 * one other driver that bothers to check for this,
635 * and cmd->underflow seems to be set rather half-
636 * heartedly in the higher-level SCSI code.
637 */
638 actual = aha274x_length(cmd,
639 scb.residual_SG_segment_count);
640
641 actual -= ((scb.residual_data_count[2] << 16) |
642 (scb.residual_data_count[1] << 8) |
643 (scb.residual_data_count[0]));
644
645 if (actual < cmd->underflow) {
646 printk("aha274x: target %d underflow - "
647 "wanted (at least) %u, got %u\n",
648 cmd->target, cmd->underflow, actual);
649
650 cmd->result = scb.target_status |
651 (DID_UNDERFLOW << 16);
652 }
653
654 cmd->scsi_done(cmd);
655
656 /*
657 * Clear interrupt status before checking
658 * the output queue again. This eliminates
659 * a race condition whereby a command could
660 * complete between the queue poll and the
661 * interrupt clearing, so notification of the
662 * command being complete never made it back
663 * up to the kernel.
664 */
665 outb(0x2, O_CLRINT(base)); /* CLRCMDINT */
666
667 } while (inb(O_QOUTCNT(base)));
668 }
669
670 if (intstat & 0x1) { /* SEQINT */
671
672 unsigned char transfer, offset, rate;
673
674 /*
675 * Although the sequencer is paused immediately on
676 * a SEQINT, an interrupt for a SCSIINT or a CMDCMPLT
677 * condition will have unpaused the sequencer before
678 * this point.
679 */
680 PAUSE_SEQUENCER(p);
681
682 switch (intstat & 0xf0) {
683 case 0x00:
684 panic("aha274x_isr: unknown scsi bus phase\n");
685 case 0x10:
686 debug("aha274x_isr warning: "
687 "issuing message reject, 1st byte 0x%x\n",
688 inb(HA_REJBYTE(base)));
689 break;
690 case 0x20:
691 panic("aha274x_isr: reconnecting target %d "
692 "didn't issue IDENTIFY message\n",
693 (inb(O_SELID(base)) >> 4) & 0xf);
694 case 0x30:
695 debug("aha274x_isr: sequencer couldn't find match "
696 "for reconnecting target %d - issuing ABORT\n",
697 (inb(O_SELID(base)) >> 4) & 0xf);
698 break;
699 case 0x40:
700 transfer = inb(HA_ARG_1(base));
701 offset = inb(HA_ARG_2(base));
702 aha274x_to_scsirate(&rate, transfer, offset);
703 outb(rate, HA_RETURN_1(base));
704 debug_rate(base, rate);
705 break;
706 default:
707 debug("aha274x_isr: seqint, "
708 "intstat = 0x%x, scsisigi = 0x%x\n",
709 intstat, inb(O_SCSISIGI(base)));
710 break;
711 }
712
713 outb(0x1, O_CLRINT(base)); /* CLRSEQINT */
714 UNPAUSE_SEQUENCER(p);
715 }
716 }
717
718 /*
719 * Probing for EISA boards: it looks like the first two bytes
720 * are a manufacturer code - three characters, five bits each:
721 *
722 * BYTE 0 BYTE 1 BYTE 2 BYTE 3
723 * ?1111122 22233333 PPPPPPPP RRRRRRRR
724 *
725 * The characters are baselined off ASCII '@', so add that value
726 * to each to get the real ASCII code for it. The next two bytes
727 * appear to be a product and revision number, probably vendor-
728 * specific. This is what is being searched for at each port,
729 * and what should probably correspond to the ID= field in the
730 * ECU's .cfg file for the card - if your card is not detected,
731 * make sure your signature is listed in the array.
732 *
733 * The fourth byte's lowest bit seems to be an enabled/disabled
734 * flag (rest of the bits are reserved?).
735 */
736
737 static
738 enum aha_type aha274x_probe(int slot, int s_base)
/* */
739 {
740 int i;
741 unsigned char buf[4];
742
743 static struct {
744 int n;
745 unsigned char signature[sizeof(buf)];
746 enum aha_type type;
747 } S[] = {
748 4, { 0x04, 0x90, 0x77, 0x71 }, T_274X, /* host adapter 274x */
749 4, { 0x04, 0x90, 0x77, 0x70 }, T_274X, /* motherboard 274x */
750 4, { 0x04, 0x90, 0x77, 0x56 }, T_284X, /* 284x, BIOS enabled */
751 };
752
753 for (i = 0; i < sizeof(buf); i++) {
754 /*
755 * The VL-bus cards need to be primed by
756 * writing before a signature check.
757 */
758 outb(0x80 + i, s_base);
759 buf[i] = inb(s_base + i);
760 }
761
762 for (i = 0; i < sizeof(S)/sizeof(S[0]); i++) {
763 if (!memcmp(buf, S[i].signature, S[i].n)) {
764 /*
765 * Signature match on enabled card?
766 */
767 if (inb(s_base + 4) & 1)
768 return(S[i].type);
769 printk("aha274x disabled at slot %d, ignored\n", slot);
770 }
771 }
772 return(T_NONE);
773 }
774
775 /*
776 * Return ' ' for plain 274x, 'T' for twin-channel, 'W' for
777 * wide channel, '?' for anything else.
778 */
779
780 static
781 char aha274x_type(int base)
/* */
782 {
783 /*
784 * The AIC-7770 can be wired so that, on chip reset,
785 * the SCSI Block Control register indicates how many
786 * busses the chip is configured for.
787 */
788 switch (inb(O_SBLKCTL(base))) {
789 case 0:
790 return(' ');
791 case 2:
792 return('W');
793 case 8:
794 return('T');
795 default:
796 printk("aha274x has unknown bus configuration\n");
797 return('?');
798 }
799 }
800
801 static
802 void aha274x_loadram(int base)
/* */
803 {
804 static unsigned char seqprog[] = {
805 /*
806 * Each sequencer instruction is 29 bits
807 * long (fill in the excess with zeroes)
808 * and has to be loaded from least -> most
809 * significant byte, so this table has the
810 * byte ordering reversed.
811 */
812 # include "aha274x_seq.h"
813 };
814
815 /*
816 * When the AIC-7770 is paused (as on chip reset), the
817 * sequencer address can be altered and a sequencer
818 * program can be loaded by writing it, byte by byte, to
819 * the sequencer RAM port - the Adaptec documentation
820 * recommends using REP OUTSB to do this, hence the inline
821 * assembly. Since the address autoincrements as we load
822 * the program, reset it back to zero afterward. Disable
823 * sequencer RAM parity error detection while loading, and
824 * make sure the LOADRAM bit is enabled for loading.
825 */
826 outb(0x83, O_SEQCTL(base)); /* PERRORDIS|SEQRESET|LOADRAM */
827
828 asm volatile("cld\n\t"
829 "rep\n\t"
830 "outsb"
831 : /* no output */
832 :"S" (seqprog), "c" (sizeof(seqprog)), "d" (O_SEQRAM(base))
833 :"si", "cx", "dx");
834
835 /*
836 * WARNING! This is a magic sequence! After extensive
837 * experimentation, it seems that you MUST turn off the
838 * LOADRAM bit before you play with SEQADDR again, else
839 * you will end up with parity errors being flagged on
840 * your sequencer program. (You would also think that
841 * turning off LOADRAM and setting SEQRESET to reset the
842 * address to zero would work, but you need to do it twice
843 * for it to take effect on the address. Timing problem?)
844 */
845 outb(0, O_SEQCTL(base));
846 do {
847 /*
848 * Actually, reset it until
849 * the address shows up as
850 * zero just to be safe..
851 */
852 outb(0x2, O_SEQCTL(base)); /* SEQRESET */
853
854 } while (inw(O_SEQADDR(base)) != 0);
855 }
856
857 static
858 int aha274x_register(Scsi_Host_Template *template,
/* */
859 enum aha_type type,
860 int base)
861 {
862 int i, irq, scsi_id;
863 struct Scsi_Host *host;
864 struct aha274x_host *p;
865
866 /*
867 * Give the AIC-7770 a reset - reading the 274x's registers
868 * returns zeroes unless you do. This forces a pause of the
869 * Sequencer.
870 */
871 outb(1, O_HCNTRL(base)); /* CHIPRST */
872
873 /*
874 * The IRQ level in i/o port 4 maps directly onto the real
875 * IRQ number. If it's ok, register it with the kernel.
876 *
877 * NB. the Adaptec documentation says the IRQ number is only
878 * in the lower four bits; the ECU information shows the
879 * high bit being used as well. Which is correct?
880 */
881 irq = inb(HA_INTDEF(base)) & 0xf;
882 if (irq < 9 || irq > 15) {
883 printk("aha274x uses unsupported IRQ level, ignoring\n");
884 return(0);
885 }
886
887 /*
888 * Lock out other contenders for our i/o space.
889 */
890 snarf_region(O_MINREG(base), O_MAXREG(base)-O_MINREG(base));
891
892 /*
893 * Any card-type-specific adjustments before we register
894 * the scsi host(s).
895 */
896
897 scsi_id = inb(HA_SCSICONF(base)) & 0x7;
898
899 switch (aha274x_type(base)) {
900 case 'T':
901 printk("aha274x warning: ignoring channel B of 274x-twin\n");
902 break;
903 case ' ':
904 break;
905 default:
906 printk("aha274x is an unsupported type, ignoring\n");
907 return(0);
908 }
909
910 /*
911 * Before registry, make sure that the offsets of the
912 * struct scatterlist are what the sequencer will expect,
913 * otherwise disable scatter-gather altogether until someone
914 * can fix it. This is important since the sequencer will
915 * DMA elements of the SG array in while executing commands.
916 */
917 if (template->sg_tablesize != SG_NONE) {
918 struct scatterlist sg;
919
920 if (SG_STRUCT_CHECK(sg)) {
921 printk("aha274x warning: kernel scatter-gather "
922 "structures changed, disabling it\n");
923 template->sg_tablesize = SG_NONE;
924 }
925 }
926
927 /*
928 * Register each "host" and fill in the returned Scsi_Host
929 * structure as best we can. Some of the parameters aren't
930 * really relevant for EISA, and none of the high-level SCSI
931 * code looks at it anyway.. why are the fields there? Also
932 * save the pointer so that we can find the information when
933 * an IRQ is triggered.
934 */
935 host = scsi_register(template, sizeof(struct aha274x_host));
936 host->this_id = scsi_id;
937 host->irq = irq;
938
939 aha274x_boards[irq] = host;
940
941 p = (struct aha274x_host *)host->hostdata;
942 for (i = 0; i < AHA274X_MAXSCB; i++)
943 p->SCB_array[i] = NULL;
944 p->base = base;
945
946 /*
947 * The interrupt trigger is different depending
948 * on whether the card is EISA or VL-bus - sometimes.
949 * The startup variable will be cleared once the first
950 * command is queued, and is checked in the isr to
951 * try and detect when the interrupt type is set
952 * incorrectly, triggering an interrupt immediately.
953 */
954 p->unpause = (type != T_274X ? 0x2 : 0xa);
955 p->startup = !0;
956
957 /*
958 * Register IRQ with the kernel _after_ the host information
959 * is set up, in case we take an interrupt right away, due to
960 * the interrupt type being set wrong.
961 */
962 if (request_irq(irq, aha274x_isr, SA_INTERRUPT, "AHA274x/284x")) {
963 printk("aha274x couldn't register irq %d, ignoring\n", irq);
964 return(0);
965 }
966
967 /*
968 * A reminder until this can be detected automatically.
969 */
970 printk("aha274x: extended translation %sabled\n",
971 aha274x_extended ? "en" : "dis");
972
973 /*
974 * Print out debugging information before re-enabling
975 * the card - a lot of registers on it can't be read
976 * when the sequencer is active.
977 */
978 debug_config(type, base);
979
980 /*
981 * Load the sequencer program, then re-enable the board -
982 * resetting the AIC-7770 disables it, leaving the lights
983 * on with nobody home.
984 */
985 aha274x_loadram(base);
986 outb(1, O_BCTL(base)); /* ENABLE */
987
988 /*
989 * Set the host adapter registers to indicate that synchronous
990 * negotiation should be attempted the first time the targets
991 * are communicated with. Also initialize the active message
992 * flag to indicate that there is no message.
993 */
994 outb(0xff, HA_NEEDSDTR(base));
995 outb(0, HA_MSG_FLAGS(base));
996
997 /*
998 * Unpause the sequencer before returning and enable
999 * interrupts - we shouldn't get any until the first
1000 * command is sent to us by the high-level SCSI code.
1001 */
1002 UNPAUSE_SEQUENCER(p);
1003 return(1);
1004 }
1005
1006 int aha274x_detect(Scsi_Host_Template *template)
/* */
1007 {
1008 enum aha_type type;
1009 int found = 0, slot, base;
1010
1011 for (slot = MINEISA; slot <= MAXEISA; slot++) {
1012
1013 base = SLOTBASE(slot);
1014
1015 if (check_region(O_MINREG(base),
1016 O_MAXREG(base)-O_MINREG(base)))
1017 {
1018 /*
1019 * Some other driver has staked a
1020 * claim to this i/o region already.
1021 */
1022 continue;
1023 }
1024
1025 type = aha274x_probe(slot, O_BIDx(base));
1026
1027 if (type != T_NONE) {
1028 /*
1029 * We "find" a 274x if we locate the card
1030 * signature and we can set it up and register
1031 * it with the kernel without incident.
1032 */
1033 found += aha274x_register(template, type, base);
1034 }
1035 }
1036 template->name = (char *)aha274x_info(NULL);
1037 return(found);
1038 }
1039
1040 const char *aha274x_info(struct Scsi_Host * shost)
/* */
1041 {
1042 return("Adaptec AHA274x/284x (EISA/VL-bus -> Fast SCSI) "
1043 AHA274X_SEQ_VERSION "/"
1044 AHA274X_H_VERSION "/"
1045 "1.29");
1046 }
1047
1048 int aha274x_command(Scsi_Cmnd *cmd)
/* */
1049 {
1050 /*
1051 * This is a relic of non-interrupt-driven SCSI
1052 * drivers. With the can_queue variable set, this
1053 * should never be called.
1054 */
1055 panic("aha274x_command was called\n");
1056 }
1057
1058 static
1059 void aha274x_buildscb(struct aha274x_host *p,
/* */
1060 Scsi_Cmnd *cmd,
1061 struct aha274x_scb *scb)
1062 {
1063 void *addr;
1064 unsigned length;
1065
1066 memset(scb, 0, sizeof(*scb));
1067
1068 /*
1069 * NB. channel selection (bit 3) is always zero.
1070 */
1071 scb->target_channel_lun = ((cmd->target << 4) & 0xf0) |
1072 (cmd->lun & 0x7);
1073
1074 /*
1075 * The interpretation of request_buffer and request_bufflen
1076 * changes depending on whether or not use_sg is zero; a
1077 * non-zero use_sg indicates the number of elements in the
1078 * scatter-gather array.
1079 *
1080 * The AIC-7770 can't support transfers of any sort larger
1081 * than 2^24 (three-byte count) without backflips. For what
1082 * the kernel is doing, this shouldn't occur. I hope.
1083 */
1084 length = aha274x_length(cmd, 0);
1085
1086 /*
1087 * The sequencer code cannot yet handle scatter-gather segments
1088 * larger than 64k (two-byte length). The 1.1.x kernels, however,
1089 * have a four-byte length field in the struct scatterlist, so
1090 * make sure we don't exceed 64k on these kernels for now.
1091 */
1092 aha274x_sg_check(cmd);
1093
1094 if (length > 0xffffff) {
1095 panic("aha274x_buildscb: can't transfer > 2^24 - 1 bytes\n");
1096 }
1097
1098 /*
1099 * XXX - this relies on the host data being stored in a
1100 * little-endian format.
1101 */
1102 addr = cmd->cmnd;
1103 scb->SCSI_cmd_length = cmd->cmd_len;
1104 memcpy(scb->SCSI_cmd_pointer, &addr, sizeof(scb->SCSI_cmd_pointer));
1105
1106 if (cmd->use_sg) {
1107 #if 0
1108 debug("aha274x_buildscb: SG used, %d segments, length %u\n",
1109 cmd->use_sg,
1110 length);
1111 #endif
1112 scb->SG_segment_count = cmd->use_sg;
1113 memcpy(scb->SG_list_pointer,
1114 &cmd->request_buffer,
1115 sizeof(scb->SG_list_pointer));
1116 } else {
1117 scb->SG_segment_count = 0;
1118 memcpy(scb->data_pointer,
1119 &cmd->request_buffer,
1120 sizeof(scb->data_pointer));
1121 memcpy(scb->data_count,
1122 &cmd->request_bufflen,
1123 sizeof(scb->data_count));
1124 }
1125 }
1126
1127 static
1128 void aha274x_putscb(int base, struct aha274x_scb *scb)
/* */
1129 {
1130 /*
1131 * By turning on the SCB auto increment, any reference
1132 * to the SCB I/O space postincrements the SCB address
1133 * we're looking at. So turn this on and dump the relevant
1134 * portion of the SCB to the card.
1135 */
1136 outb(0x80, O_SCBCNT(base)); /* SCBAUTO */
1137
1138 asm volatile("cld\n\t"
1139 "rep\n\t"
1140 "outsb"
1141 : /* no output */
1142 :"S" (scb), "c" (sizeof(*scb)), "d" (O_SCBARRAY(base))
1143 :"si", "cx", "dx");
1144
1145 outb(0, O_SCBCNT(base));
1146 }
1147
1148 int aha274x_queue(Scsi_Cmnd *cmd, void (*fn)(Scsi_Cmnd *))
/* */
1149 {
1150 long flags;
1151 int empty, old_scbptr;
1152 struct aha274x_host *p;
1153 struct aha274x_scb scb;
1154
1155 #if 0
1156 debug("aha274x_queue: cmd 0x%x (size %u), target %d, lun %d\n",
1157 cmd->cmnd[0],
1158 cmd->cmd_len,
1159 cmd->target,
1160 cmd->lun);
1161 #endif
1162
1163 p = (struct aha274x_host *)cmd->host->hostdata;
1164
1165 /*
1166 * Construct the SCB beforehand, so the sequencer is
1167 * paused a minimal amount of time.
1168 */
1169 aha274x_buildscb(p, cmd, &scb);
1170
1171 /*
1172 * Clear the startup flag - we can now legitimately
1173 * expect interrupts.
1174 */
1175 p->startup = 0;
1176
1177 /*
1178 * This is a critical section, since we don't want the
1179 * interrupt routine mucking with the host data or the
1180 * card. Since the kernel documentation is vague on
1181 * whether or not we are in a cli/sti pair already, save
1182 * the flags to be on the safe side.
1183 */
1184 save_flags(flags);
1185 cli();
1186
1187 /*
1188 * Find a free slot in the SCB array to load this command
1189 * into. Since can_queue is set to AHA274X_MAXSCB, we
1190 * should always find one.
1191 */
1192 for (empty = 0; empty < AHA274X_MAXSCB; empty++)
1193 if (!p->SCB_array[empty])
1194 break;
1195 if (empty == AHA274X_MAXSCB)
1196 panic("aha274x_queue: couldn't find a free scb\n");
1197
1198 /*
1199 * Pause the sequencer so we can play with its registers -
1200 * wait for it to acknowledge the pause.
1201 *
1202 * XXX - should the interrupts be left on while doing this?
1203 */
1204 PAUSE_SEQUENCER(p);
1205
1206 /*
1207 * Save the SCB pointer and put our own pointer in - this
1208 * selects one of the four banks of SCB registers. Load
1209 * the SCB, then write its pointer into the queue in FIFO
1210 * and restore the saved SCB pointer.
1211 */
1212 old_scbptr = inb(O_SCBPTR(p->base));
1213 outb(empty, O_SCBPTR(p->base));
1214
1215 aha274x_putscb(p->base, &scb);
1216
1217 outb(empty, O_QINFIFO(p->base));
1218 outb(old_scbptr, O_SCBPTR(p->base));
1219
1220 /*
1221 * Make sure the Scsi_Cmnd pointer is saved, the struct it
1222 * points to is set up properly, and the parity error flag
1223 * is reset, then unpause the sequencer and watch the fun
1224 * begin.
1225 */
1226 cmd->scsi_done = fn;
1227 p->SCB_array[empty] = cmd;
1228 aha274x_parity(cmd) = DID_OK;
1229
1230 UNPAUSE_SEQUENCER(p);
1231
1232 restore_flags(flags);
1233 return(0);
1234 }
1235
1236 /* return values from aha274x_kill */
1237
1238 enum k_state {
1239 k_ok, /* scb found and message sent */
1240 k_busy, /* message already present */
1241 k_absent, /* couldn't locate scb */
1242 k_disconnect, /* scb found, but disconnected */
1243 };
1244
1245 /*
1246 * This must be called with interrupts disabled - it's going to
1247 * be messing around with the host data, and an interrupt being
1248 * fielded in the middle could get ugly.
1249 *
1250 * Since so much of the abort and reset code is shared, this
1251 * function performs more magic than it really should. If the
1252 * command completes ok, then it will call scsi_done with the
1253 * result code passed in. The unpause parameter controls whether
1254 * or not the sequencer gets unpaused - the reset function, for
1255 * instance, may want to do something more aggressive.
1256 *
1257 * Note that the command is checked for in our SCB_array first
1258 * before the sequencer is paused, so if k_absent is returned,
1259 * then the sequencer is NOT paused.
1260 */
1261
1262 static
1263 enum k_state aha274x_kill(Scsi_Cmnd *cmd, unsigned char message,
/* */
1264 unsigned int result, int unpause)
1265 {
1266 struct aha274x_host *p;
1267 int i, scb, found, queued;
1268 unsigned char scbsave[AHA274X_MAXSCB];
1269
1270 p = (struct aha274x_host *)cmd->host->hostdata;
1271
1272 /*
1273 * If we can't find the command, assume it just completed
1274 * and shrug it away.
1275 */
1276 for (scb = 0; scb < AHA274X_MAXSCB; scb++)
1277 if (p->SCB_array[scb] == cmd)
1278 break;
1279
1280 if (scb == AHA274X_MAXSCB)
1281 return(k_absent);
1282
1283 PAUSE_SEQUENCER(p);
1284
1285 /*
1286 * This is the best case, really. Check to see if the
1287 * command is still in the sequencer's input queue. If
1288 * so, simply remove it. Reload the queue afterward.
1289 */
1290 queued = inb(O_QINCNT(p->base));
1291
1292 for (i = found = 0; i < queued; i++) {
1293 scbsave[i] = inb(O_QINFIFO(p->base));
1294
1295 if (scbsave[i] == scb) {
1296 found = 1;
1297 i -= 1;
1298 }
1299 }
1300
1301 queued -= found;
1302 for (i = 0; i < queued; i++)
1303 outb(scbsave[i], O_QINFIFO(p->base));
1304
1305 if (found)
1306 goto complete;
1307
1308 /*
1309 * Check the current SCB bank. If it's not the one belonging
1310 * to the command we want to kill, assume that the command
1311 * is disconnected. It's rather a pain to force a reconnect
1312 * and send a message to the target, so we abdicate responsibility
1313 * in this case.
1314 */
1315 if (inb(O_SCBPTR(p->base)) != scb) {
1316 if (unpause)
1317 UNPAUSE_SEQUENCER(p);
1318 return(k_disconnect);
1319 }
1320
1321 /*
1322 * Presumably at this point our target command is active. Check
1323 * to see if there's a message already in effect. If not, place
1324 * our message in and assert ATN so the target goes into MESSAGE
1325 * OUT phase.
1326 */
1327 if (inb(HA_MSG_FLAGS(p->base)) & 0x80) {
1328 if (unpause)
1329 UNPAUSE_SEQUENCER(p);
1330 return(k_busy);
1331 }
1332
1333 outb(0x80, HA_MSG_FLAGS(p->base)); /* active message */
1334 outb(1, HA_MSG_LEN(p->base)); /* length = 1 */
1335 outb(message, HA_MSG_START(p->base)); /* message body */
1336
1337 /*
1338 * Assert ATN. Use the value of SCSISIGO saved by the
1339 * sequencer code so we don't alter its contents radically
1340 * in the middle of something critical.
1341 */
1342 outb(inb(HA_SIGSTATE(p->base)) | 0x10, O_SCSISIGO(p->base));
1343
1344 /*
1345 * The command has been killed. Do the bookkeeping, unpause
1346 * the sequencer, and notify the higher-level SCSI code.
1347 */
1348 complete:
1349 p->SCB_array[scb] = NULL;
1350 if (unpause)
1351 UNPAUSE_SEQUENCER(p);
1352
1353 cmd->result = result << 16;
1354 cmd->scsi_done(cmd);
1355 return(k_ok);
1356 }
1357
1358 int aha274x_abort(Scsi_Cmnd *cmd)
/* */
1359 {
1360 int rv;
1361 long flags;
1362
1363 save_flags(flags);
1364 cli();
1365
1366 switch (aha274x_kill(cmd, ABORT, DID_ABORT, !0)) {
1367 case k_ok: rv = SCSI_ABORT_SUCCESS; break;
1368 case k_busy: rv = SCSI_ABORT_BUSY; break;
1369 case k_absent: rv = SCSI_ABORT_NOT_RUNNING; break;
1370 case k_disconnect: rv = SCSI_ABORT_SNOOZE; break;
1371 default:
1372 panic("aha274x_do_abort: internal error\n");
1373 }
1374
1375 restore_flags(flags);
1376 return(rv);
1377 }
1378
1379 /*
1380 * Resetting the bus always succeeds - is has to, otherwise the
1381 * kernel will panic! Try a surgical technique - sending a BUS
1382 * DEVICE RESET message - on the offending target before pulling
1383 * the SCSI bus reset line.
1384 */
1385
1386 int aha274x_reset(Scsi_Cmnd *cmd)
/* */
1387 {
1388 int i;
1389 long flags;
1390 Scsi_Cmnd *reset;
1391 struct aha274x_host *p;
1392
1393 p = (struct aha274x_host *)cmd->host->hostdata;
1394 save_flags(flags);
1395 cli();
1396
1397 switch (aha274x_kill(cmd, BUS_DEVICE_RESET, DID_RESET, 0)) {
1398
1399 case k_ok:
1400 /*
1401 * The RESET message was sent to the target
1402 * with no problems. Flag that target as
1403 * needing a SDTR negotiation on the next
1404 * connection and restart the sequencer.
1405 */
1406 outb((1 << cmd->target), HA_NEEDSDTR(p->base));
1407 UNPAUSE_SEQUENCER(p);
1408 break;
1409
1410 case k_absent:
1411 /*
1412 * The sequencer will not be paused if aha274x_kill()
1413 * couldn't find the command.
1414 */
1415 PAUSE_SEQUENCER(p);
1416 /* falls through */
1417
1418 case k_busy:
1419 case k_disconnect:
1420 /*
1421 * Do a hard reset of the SCSI bus. According to the
1422 * SCSI-2 draft specification, reset has to be asserted
1423 * for at least 25us. I'm invoking the kernel delay
1424 * function for 30us since I'm not totally trusting of
1425 * the busy loop timing.
1426 *
1427 * XXX - I'm not convinced this works. I tried resetting
1428 * the bus before, trying to get the devices on the
1429 * bus to revert to asynchronous transfer, and it
1430 * never seemed to work.
1431 */
1432 debug("aha274x: attempting to reset scsi bus and card\n");
1433
1434 outb(1, O_SCSISEQ(p->base)); /* SCSIRSTO */
1435 udelay(30);
1436 outb(0, O_SCSISEQ(p->base)); /* !SCSIRSTO */
1437
1438 outb(0xff, HA_NEEDSDTR(p->base));
1439 UNPAUSE_SEQUENCER(p);
1440
1441 /*
1442 * Locate the command and return a "reset" status
1443 * for it. This is not completely correct and will
1444 * probably return to haunt me later.
1445 */
1446 for (i = 0; i < AHA274X_MAXSCB; i++) {
1447 if (cmd == p->SCB_array[i]) {
1448 reset = (Scsi_Cmnd *)p->SCB_array[i];
1449 p->SCB_array[i] = NULL;
1450 reset->result = DID_RESET << 16;
1451 reset->scsi_done(reset);
1452 break;
1453 }
1454 }
1455 break;
1456
1457 default:
1458 panic("aha274x_reset: internal error\n");
1459 }
1460
1461 restore_flags(flags);
1462 return(SCSI_RESET_SUCCESS);
1463 }
1464
1465 int aha274x_biosparam(Disk *disk, int devno, int geom[])
/* ![[last]](../icons/n_last.png)
*/
1466 {
1467 int heads, sectors, cylinders;
1468
1469 /*
1470 * XXX - if I could portably find the card's configuration
1471 * information, then this could be autodetected instead
1472 * of left to a boot-time switch.
1473 */
1474 heads = 64;
1475 sectors = 32;
1476 cylinders = disk->capacity / (heads * sectors);
1477
1478 if (aha274x_extended && cylinders > 1024) {
1479 heads = 255;
1480 sectors = 63;
1481 cylinders = disk->capacity / (255 * 63);
1482 }
1483
1484 geom[0] = heads;
1485 geom[1] = sectors;
1486 geom[2] = cylinders;
1487
1488 return(0);
1489 }
1490
![[bottom]](../icons/n_bottom.png){kind=icon}
*/