xref: /linux/drivers/scsi/wd33c93.c (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
1 /*
2  * Copyright (c) 1996 John Shifflett, GeoLog Consulting
3  *    john@geolog.com
4  *    jshiffle@netcom.com
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2, or (at your option)
9  * any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 /*
18  * Drew Eckhardt's excellent 'Generic NCR5380' sources from Linux-PC
19  * provided much of the inspiration and some of the code for this
20  * driver. Everything I know about Amiga DMA was gleaned from careful
21  * reading of Hamish Mcdonald's original wd33c93 driver; in fact, I
22  * borrowed shamelessly from all over that source. Thanks Hamish!
23  *
24  * _This_ driver is (I feel) an improvement over the old one in
25  * several respects:
26  *
27  *    -  Target Disconnection/Reconnection  is now supported. Any
28  *          system with more than one device active on the SCSI bus
29  *          will benefit from this. The driver defaults to what I
30  *          call 'adaptive disconnect' - meaning that each command
31  *          is evaluated individually as to whether or not it should
32  *          be run with the option to disconnect/reselect (if the
33  *          device chooses), or as a "SCSI-bus-hog".
34  *
35  *    -  Synchronous data transfers are now supported. Because of
36  *          a few devices that choke after telling the driver that
37  *          they can do sync transfers, we don't automatically use
38  *          this faster protocol - it can be enabled via the command-
39  *          line on a device-by-device basis.
40  *
41  *    -  Runtime operating parameters can now be specified through
42  *       the 'amiboot' or the 'insmod' command line. For amiboot do:
43  *          "amiboot [usual stuff] wd33c93=blah,blah,blah"
44  *       The defaults should be good for most people. See the comment
45  *       for 'setup_strings' below for more details.
46  *
47  *    -  The old driver relied exclusively on what the Western Digital
48  *          docs call "Combination Level 2 Commands", which are a great
49  *          idea in that the CPU is relieved of a lot of interrupt
50  *          overhead. However, by accepting a certain (user-settable)
51  *          amount of additional interrupts, this driver achieves
52  *          better control over the SCSI bus, and data transfers are
53  *          almost as fast while being much easier to define, track,
54  *          and debug.
55  *
56  *
57  * TODO:
58  *       more speed. linked commands.
59  *
60  *
61  * People with bug reports, wish-lists, complaints, comments,
62  * or improvements are asked to pah-leeez email me (John Shifflett)
63  * at john@geolog.com or jshiffle@netcom.com! I'm anxious to get
64  * this thing into as good a shape as possible, and I'm positive
65  * there are lots of lurking bugs and "Stupid Places".
66  *
67  * Updates:
68  *
69  * Added support for pre -A chips, which don't have advanced features
70  * and will generate CSR_RESEL rather than CSR_RESEL_AM.
71  *	Richard Hirst <richard@sleepie.demon.co.uk>  August 2000
72  *
73  * Added support for Burst Mode DMA and Fast SCSI. Enabled the use of
74  * default_sx_per for asynchronous data transfers. Added adjustment
75  * of transfer periods in sx_table to the actual input-clock.
76  *  peter fuerst <post@pfrst.de>  February 2007
77  */
78 
79 #include <linux/module.h>
80 
81 #include <linux/string.h>
82 #include <linux/delay.h>
83 #include <linux/init.h>
84 #include <linux/interrupt.h>
85 #include <linux/blkdev.h>
86 
87 #include <scsi/scsi.h>
88 #include <scsi/scsi_cmnd.h>
89 #include <scsi/scsi_device.h>
90 #include <scsi/scsi_host.h>
91 
92 #include <asm/irq.h>
93 
94 #include "wd33c93.h"
95 
96 #define optimum_sx_per(hostdata) (hostdata)->sx_table[1].period_ns
97 
98 
99 #define WD33C93_VERSION    "1.26++"
100 #define WD33C93_DATE       "10/Feb/2007"
101 
102 MODULE_AUTHOR("John Shifflett");
103 MODULE_DESCRIPTION("Generic WD33C93 SCSI driver");
104 MODULE_LICENSE("GPL");
105 
106 /*
107  * 'setup_strings' is a single string used to pass operating parameters and
108  * settings from the kernel/module command-line to the driver. 'setup_args[]'
109  * is an array of strings that define the compile-time default values for
110  * these settings. If Linux boots with an amiboot or insmod command-line,
111  * those settings are combined with 'setup_args[]'. Note that amiboot
112  * command-lines are prefixed with "wd33c93=" while insmod uses a
113  * "setup_strings=" prefix. The driver recognizes the following keywords
114  * (lower case required) and arguments:
115  *
116  * -  nosync:bitmask -bitmask is a byte where the 1st 7 bits correspond with
117  *                    the 7 possible SCSI devices. Set a bit to negotiate for
118  *                    asynchronous transfers on that device. To maintain
119  *                    backwards compatibility, a command-line such as
120  *                    "wd33c93=255" will be automatically translated to
121  *                    "wd33c93=nosync:0xff".
122  * -  nodma:x        -x = 1 to disable DMA, x = 0 to enable it. Argument is
123  *                    optional - if not present, same as "nodma:1".
124  * -  period:ns      -ns is the minimum # of nanoseconds in a SCSI data transfer
125  *                    period. Default is 500; acceptable values are 250 - 1000.
126  * -  disconnect:x   -x = 0 to never allow disconnects, 2 to always allow them.
127  *                    x = 1 does 'adaptive' disconnects, which is the default
128  *                    and generally the best choice.
129  * -  debug:x        -If 'DEBUGGING_ON' is defined, x is a bit mask that causes
130  *                    various types of debug output to printed - see the DB_xxx
131  *                    defines in wd33c93.h
132  * -  clock:x        -x = clock input in MHz for WD33c93 chip. Normal values
133  *                    would be from 8 through 20. Default is 8.
134  * -  burst:x        -x = 1 to use Burst Mode (or Demand-Mode) DMA, x = 0 to use
135  *                    Single Byte DMA, which is the default. Argument is
136  *                    optional - if not present, same as "burst:1".
137  * -  fast:x         -x = 1 to enable Fast SCSI, which is only effective with
138  *                    input-clock divisor 4 (WD33C93_FS_16_20), x = 0 to disable
139  *                    it, which is the default.  Argument is optional - if not
140  *                    present, same as "fast:1".
141  * -  next           -No argument. Used to separate blocks of keywords when
142  *                    there's more than one host adapter in the system.
143  *
144  * Syntax Notes:
145  * -  Numeric arguments can be decimal or the '0x' form of hex notation. There
146  *    _must_ be a colon between a keyword and its numeric argument, with no
147  *    spaces.
148  * -  Keywords are separated by commas, no spaces, in the standard kernel
149  *    command-line manner.
150  * -  A keyword in the 'nth' comma-separated command-line member will overwrite
151  *    the 'nth' element of setup_args[]. A blank command-line member (in
152  *    other words, a comma with no preceding keyword) will _not_ overwrite
153  *    the corresponding setup_args[] element.
154  * -  If a keyword is used more than once, the first one applies to the first
155  *    SCSI host found, the second to the second card, etc, unless the 'next'
156  *    keyword is used to change the order.
157  *
158  * Some amiboot examples (for insmod, use 'setup_strings' instead of 'wd33c93'):
159  * -  wd33c93=nosync:255
160  * -  wd33c93=nodma
161  * -  wd33c93=nodma:1
162  * -  wd33c93=disconnect:2,nosync:0x08,period:250
163  * -  wd33c93=debug:0x1c
164  */
165 
166 /* Normally, no defaults are specified */
167 static char *setup_args[] = { "", "", "", "", "", "", "", "", "", "" };
168 
169 static char *setup_strings;
170 module_param(setup_strings, charp, 0);
171 
172 static void wd33c93_execute(struct Scsi_Host *instance);
173 
174 #ifdef CONFIG_WD33C93_PIO
175 static inline uchar
176 read_wd33c93(const wd33c93_regs regs, uchar reg_num)
177 {
178 	uchar data;
179 
180 	outb(reg_num, regs.SASR);
181 	data = inb(regs.SCMD);
182 	return data;
183 }
184 
185 static inline unsigned long
186 read_wd33c93_count(const wd33c93_regs regs)
187 {
188 	unsigned long value;
189 
190 	outb(WD_TRANSFER_COUNT_MSB, regs.SASR);
191 	value = inb(regs.SCMD) << 16;
192 	value |= inb(regs.SCMD) << 8;
193 	value |= inb(regs.SCMD);
194 	return value;
195 }
196 
197 static inline uchar
198 read_aux_stat(const wd33c93_regs regs)
199 {
200 	return inb(regs.SASR);
201 }
202 
203 static inline void
204 write_wd33c93(const wd33c93_regs regs, uchar reg_num, uchar value)
205 {
206       outb(reg_num, regs.SASR);
207       outb(value, regs.SCMD);
208 }
209 
210 static inline void
211 write_wd33c93_count(const wd33c93_regs regs, unsigned long value)
212 {
213 	outb(WD_TRANSFER_COUNT_MSB, regs.SASR);
214 	outb((value >> 16) & 0xff, regs.SCMD);
215 	outb((value >> 8) & 0xff, regs.SCMD);
216 	outb( value & 0xff, regs.SCMD);
217 }
218 
219 #define write_wd33c93_cmd(regs, cmd) \
220 	write_wd33c93((regs), WD_COMMAND, (cmd))
221 
222 static inline void
223 write_wd33c93_cdb(const wd33c93_regs regs, uint len, uchar cmnd[])
224 {
225 	int i;
226 
227 	outb(WD_CDB_1, regs.SASR);
228 	for (i=0; i<len; i++)
229 		outb(cmnd[i], regs.SCMD);
230 }
231 
232 #else /* CONFIG_WD33C93_PIO */
233 static inline uchar
234 read_wd33c93(const wd33c93_regs regs, uchar reg_num)
235 {
236 	*regs.SASR = reg_num;
237 	mb();
238 	return (*regs.SCMD);
239 }
240 
241 static unsigned long
242 read_wd33c93_count(const wd33c93_regs regs)
243 {
244 	unsigned long value;
245 
246 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
247 	mb();
248 	value = *regs.SCMD << 16;
249 	value |= *regs.SCMD << 8;
250 	value |= *regs.SCMD;
251 	mb();
252 	return value;
253 }
254 
255 static inline uchar
256 read_aux_stat(const wd33c93_regs regs)
257 {
258 	return *regs.SASR;
259 }
260 
261 static inline void
262 write_wd33c93(const wd33c93_regs regs, uchar reg_num, uchar value)
263 {
264 	*regs.SASR = reg_num;
265 	mb();
266 	*regs.SCMD = value;
267 	mb();
268 }
269 
270 static void
271 write_wd33c93_count(const wd33c93_regs regs, unsigned long value)
272 {
273 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
274 	mb();
275 	*regs.SCMD = value >> 16;
276 	*regs.SCMD = value >> 8;
277 	*regs.SCMD = value;
278 	mb();
279 }
280 
281 static inline void
282 write_wd33c93_cmd(const wd33c93_regs regs, uchar cmd)
283 {
284 	*regs.SASR = WD_COMMAND;
285 	mb();
286 	*regs.SCMD = cmd;
287 	mb();
288 }
289 
290 static inline void
291 write_wd33c93_cdb(const wd33c93_regs regs, uint len, uchar cmnd[])
292 {
293 	int i;
294 
295 	*regs.SASR = WD_CDB_1;
296 	for (i = 0; i < len; i++)
297 		*regs.SCMD = cmnd[i];
298 }
299 #endif /* CONFIG_WD33C93_PIO */
300 
301 static inline uchar
302 read_1_byte(const wd33c93_regs regs)
303 {
304 	uchar asr;
305 	uchar x = 0;
306 
307 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
308 	write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO | 0x80);
309 	do {
310 		asr = read_aux_stat(regs);
311 		if (asr & ASR_DBR)
312 			x = read_wd33c93(regs, WD_DATA);
313 	} while (!(asr & ASR_INT));
314 	return x;
315 }
316 
317 static int
318 round_period(unsigned int period, const struct sx_period *sx_table)
319 {
320 	int x;
321 
322 	for (x = 1; sx_table[x].period_ns; x++) {
323 		if ((period <= sx_table[x - 0].period_ns) &&
324 		    (period > sx_table[x - 1].period_ns)) {
325 			return x;
326 		}
327 	}
328 	return 7;
329 }
330 
331 /*
332  * Calculate Synchronous Transfer Register value from SDTR code.
333  */
334 static uchar
335 calc_sync_xfer(unsigned int period, unsigned int offset, unsigned int fast,
336                const struct sx_period *sx_table)
337 {
338 	/* When doing Fast SCSI synchronous data transfers, the corresponding
339 	 * value in 'sx_table' is two times the actually used transfer period.
340 	 */
341 	uchar result;
342 
343 	if (offset && fast) {
344 		fast = STR_FSS;
345 		period *= 2;
346 	} else {
347 		fast = 0;
348 	}
349 	period *= 4;		/* convert SDTR code to ns */
350 	result = sx_table[round_period(period,sx_table)].reg_value;
351 	result |= (offset < OPTIMUM_SX_OFF) ? offset : OPTIMUM_SX_OFF;
352 	result |= fast;
353 	return result;
354 }
355 
356 /*
357  * Calculate SDTR code bytes [3],[4] from period and offset.
358  */
359 static inline void
360 calc_sync_msg(unsigned int period, unsigned int offset, unsigned int fast,
361                 uchar  msg[2])
362 {
363 	/* 'period' is a "normal"-mode value, like the ones in 'sx_table'. The
364 	 * actually used transfer period for Fast SCSI synchronous data
365 	 * transfers is half that value.
366 	 */
367 	period /= 4;
368 	if (offset && fast)
369 		period /= 2;
370 	msg[0] = period;
371 	msg[1] = offset;
372 }
373 
374 int
375 wd33c93_queuecommand(struct scsi_cmnd *cmd,
376 		void (*done)(struct scsi_cmnd *))
377 {
378 	struct WD33C93_hostdata *hostdata;
379 	struct scsi_cmnd *tmp;
380 
381 	hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
382 
383 	DB(DB_QUEUE_COMMAND,
384 	   printk("Q-%d-%02x-%ld( ", cmd->device->id, cmd->cmnd[0], cmd->serial_number))
385 
386 /* Set up a few fields in the scsi_cmnd structure for our own use:
387  *  - host_scribble is the pointer to the next cmd in the input queue
388  *  - scsi_done points to the routine we call when a cmd is finished
389  *  - result is what you'd expect
390  */
391 	cmd->host_scribble = NULL;
392 	cmd->scsi_done = done;
393 	cmd->result = 0;
394 
395 /* We use the Scsi_Pointer structure that's included with each command
396  * as a scratchpad (as it's intended to be used!). The handy thing about
397  * the SCp.xxx fields is that they're always associated with a given
398  * cmd, and are preserved across disconnect-reselect. This means we
399  * can pretty much ignore SAVE_POINTERS and RESTORE_POINTERS messages
400  * if we keep all the critical pointers and counters in SCp:
401  *  - SCp.ptr is the pointer into the RAM buffer
402  *  - SCp.this_residual is the size of that buffer
403  *  - SCp.buffer points to the current scatter-gather buffer
404  *  - SCp.buffers_residual tells us how many S.G. buffers there are
405  *  - SCp.have_data_in is not used
406  *  - SCp.sent_command is not used
407  *  - SCp.phase records this command's SRCID_ER bit setting
408  */
409 
410 	if (scsi_bufflen(cmd)) {
411 		cmd->SCp.buffer = scsi_sglist(cmd);
412 		cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
413 		cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
414 		cmd->SCp.this_residual = cmd->SCp.buffer->length;
415 	} else {
416 		cmd->SCp.buffer = NULL;
417 		cmd->SCp.buffers_residual = 0;
418 		cmd->SCp.ptr = NULL;
419 		cmd->SCp.this_residual = 0;
420 	}
421 
422 /* WD docs state that at the conclusion of a "LEVEL2" command, the
423  * status byte can be retrieved from the LUN register. Apparently,
424  * this is the case only for *uninterrupted* LEVEL2 commands! If
425  * there are any unexpected phases entered, even if they are 100%
426  * legal (different devices may choose to do things differently),
427  * the LEVEL2 command sequence is exited. This often occurs prior
428  * to receiving the status byte, in which case the driver does a
429  * status phase interrupt and gets the status byte on its own.
430  * While such a command can then be "resumed" (ie restarted to
431  * finish up as a LEVEL2 command), the LUN register will NOT be
432  * a valid status byte at the command's conclusion, and we must
433  * use the byte obtained during the earlier interrupt. Here, we
434  * preset SCp.Status to an illegal value (0xff) so that when
435  * this command finally completes, we can tell where the actual
436  * status byte is stored.
437  */
438 
439 	cmd->SCp.Status = ILLEGAL_STATUS_BYTE;
440 
441 	/*
442 	 * Add the cmd to the end of 'input_Q'. Note that REQUEST SENSE
443 	 * commands are added to the head of the queue so that the desired
444 	 * sense data is not lost before REQUEST_SENSE executes.
445 	 */
446 
447 	spin_lock_irq(&hostdata->lock);
448 
449 	if (!(hostdata->input_Q) || (cmd->cmnd[0] == REQUEST_SENSE)) {
450 		cmd->host_scribble = (uchar *) hostdata->input_Q;
451 		hostdata->input_Q = cmd;
452 	} else {		/* find the end of the queue */
453 		for (tmp = (struct scsi_cmnd *) hostdata->input_Q;
454 		     tmp->host_scribble;
455 		     tmp = (struct scsi_cmnd *) tmp->host_scribble) ;
456 		tmp->host_scribble = (uchar *) cmd;
457 	}
458 
459 /* We know that there's at least one command in 'input_Q' now.
460  * Go see if any of them are runnable!
461  */
462 
463 	wd33c93_execute(cmd->device->host);
464 
465 	DB(DB_QUEUE_COMMAND, printk(")Q-%ld ", cmd->serial_number))
466 
467 	spin_unlock_irq(&hostdata->lock);
468 	return 0;
469 }
470 
471 /*
472  * This routine attempts to start a scsi command. If the host_card is
473  * already connected, we give up immediately. Otherwise, look through
474  * the input_Q, using the first command we find that's intended
475  * for a currently non-busy target/lun.
476  *
477  * wd33c93_execute() is always called with interrupts disabled or from
478  * the wd33c93_intr itself, which means that a wd33c93 interrupt
479  * cannot occur while we are in here.
480  */
481 static void
482 wd33c93_execute(struct Scsi_Host *instance)
483 {
484 	struct WD33C93_hostdata *hostdata =
485 	    (struct WD33C93_hostdata *) instance->hostdata;
486 	const wd33c93_regs regs = hostdata->regs;
487 	struct scsi_cmnd *cmd, *prev;
488 
489 	DB(DB_EXECUTE, printk("EX("))
490 	if (hostdata->selecting || hostdata->connected) {
491 		DB(DB_EXECUTE, printk(")EX-0 "))
492 		return;
493 	}
494 
495 	/*
496 	 * Search through the input_Q for a command destined
497 	 * for an idle target/lun.
498 	 */
499 
500 	cmd = (struct scsi_cmnd *) hostdata->input_Q;
501 	prev = NULL;
502 	while (cmd) {
503 		if (!(hostdata->busy[cmd->device->id] & (1 << cmd->device->lun)))
504 			break;
505 		prev = cmd;
506 		cmd = (struct scsi_cmnd *) cmd->host_scribble;
507 	}
508 
509 	/* quit if queue empty or all possible targets are busy */
510 
511 	if (!cmd) {
512 		DB(DB_EXECUTE, printk(")EX-1 "))
513 		return;
514 	}
515 
516 	/*  remove command from queue */
517 
518 	if (prev)
519 		prev->host_scribble = cmd->host_scribble;
520 	else
521 		hostdata->input_Q = (struct scsi_cmnd *) cmd->host_scribble;
522 
523 #ifdef PROC_STATISTICS
524 	hostdata->cmd_cnt[cmd->device->id]++;
525 #endif
526 
527 	/*
528 	 * Start the selection process
529 	 */
530 
531 	if (cmd->sc_data_direction == DMA_TO_DEVICE)
532 		write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
533 	else
534 		write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id | DSTID_DPD);
535 
536 /* Now we need to figure out whether or not this command is a good
537  * candidate for disconnect/reselect. We guess to the best of our
538  * ability, based on a set of hierarchical rules. When several
539  * devices are operating simultaneously, disconnects are usually
540  * an advantage. In a single device system, or if only 1 device
541  * is being accessed, transfers usually go faster if disconnects
542  * are not allowed:
543  *
544  * + Commands should NEVER disconnect if hostdata->disconnect =
545  *   DIS_NEVER (this holds for tape drives also), and ALWAYS
546  *   disconnect if hostdata->disconnect = DIS_ALWAYS.
547  * + Tape drive commands should always be allowed to disconnect.
548  * + Disconnect should be allowed if disconnected_Q isn't empty.
549  * + Commands should NOT disconnect if input_Q is empty.
550  * + Disconnect should be allowed if there are commands in input_Q
551  *   for a different target/lun. In this case, the other commands
552  *   should be made disconnect-able, if not already.
553  *
554  * I know, I know - this code would flunk me out of any
555  * "C Programming 101" class ever offered. But it's easy
556  * to change around and experiment with for now.
557  */
558 
559 	cmd->SCp.phase = 0;	/* assume no disconnect */
560 	if (hostdata->disconnect == DIS_NEVER)
561 		goto no;
562 	if (hostdata->disconnect == DIS_ALWAYS)
563 		goto yes;
564 	if (cmd->device->type == 1)	/* tape drive? */
565 		goto yes;
566 	if (hostdata->disconnected_Q)	/* other commands disconnected? */
567 		goto yes;
568 	if (!(hostdata->input_Q))	/* input_Q empty? */
569 		goto no;
570 	for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
571 	     prev = (struct scsi_cmnd *) prev->host_scribble) {
572 		if ((prev->device->id != cmd->device->id) ||
573 		    (prev->device->lun != cmd->device->lun)) {
574 			for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
575 			     prev = (struct scsi_cmnd *) prev->host_scribble)
576 				prev->SCp.phase = 1;
577 			goto yes;
578 		}
579 	}
580 
581 	goto no;
582 
583  yes:
584 	cmd->SCp.phase = 1;
585 
586 #ifdef PROC_STATISTICS
587 	hostdata->disc_allowed_cnt[cmd->device->id]++;
588 #endif
589 
590  no:
591 
592 	write_wd33c93(regs, WD_SOURCE_ID, ((cmd->SCp.phase) ? SRCID_ER : 0));
593 
594 	write_wd33c93(regs, WD_TARGET_LUN, cmd->device->lun);
595 	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
596 		      hostdata->sync_xfer[cmd->device->id]);
597 	hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
598 
599 	if ((hostdata->level2 == L2_NONE) ||
600 	    (hostdata->sync_stat[cmd->device->id] == SS_UNSET)) {
601 
602 		/*
603 		 * Do a 'Select-With-ATN' command. This will end with
604 		 * one of the following interrupts:
605 		 *    CSR_RESEL_AM:  failure - can try again later.
606 		 *    CSR_TIMEOUT:   failure - give up.
607 		 *    CSR_SELECT:    success - proceed.
608 		 */
609 
610 		hostdata->selecting = cmd;
611 
612 /* Every target has its own synchronous transfer setting, kept in the
613  * sync_xfer array, and a corresponding status byte in sync_stat[].
614  * Each target's sync_stat[] entry is initialized to SX_UNSET, and its
615  * sync_xfer[] entry is initialized to the default/safe value. SS_UNSET
616  * means that the parameters are undetermined as yet, and that we
617  * need to send an SDTR message to this device after selection is
618  * complete: We set SS_FIRST to tell the interrupt routine to do so.
619  * If we've been asked not to try synchronous transfers on this
620  * target (and _all_ luns within it), we'll still send the SDTR message
621  * later, but at that time we'll negotiate for async by specifying a
622  * sync fifo depth of 0.
623  */
624 		if (hostdata->sync_stat[cmd->device->id] == SS_UNSET)
625 			hostdata->sync_stat[cmd->device->id] = SS_FIRST;
626 		hostdata->state = S_SELECTING;
627 		write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
628 		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN);
629 	} else {
630 
631 		/*
632 		 * Do a 'Select-With-ATN-Xfer' command. This will end with
633 		 * one of the following interrupts:
634 		 *    CSR_RESEL_AM:  failure - can try again later.
635 		 *    CSR_TIMEOUT:   failure - give up.
636 		 *    anything else: success - proceed.
637 		 */
638 
639 		hostdata->connected = cmd;
640 		write_wd33c93(regs, WD_COMMAND_PHASE, 0);
641 
642 		/* copy command_descriptor_block into WD chip
643 		 * (take advantage of auto-incrementing)
644 		 */
645 
646 		write_wd33c93_cdb(regs, cmd->cmd_len, cmd->cmnd);
647 
648 		/* The wd33c93 only knows about Group 0, 1, and 5 commands when
649 		 * it's doing a 'select-and-transfer'. To be safe, we write the
650 		 * size of the CDB into the OWN_ID register for every case. This
651 		 * way there won't be problems with vendor-unique, audio, etc.
652 		 */
653 
654 		write_wd33c93(regs, WD_OWN_ID, cmd->cmd_len);
655 
656 		/* When doing a non-disconnect command with DMA, we can save
657 		 * ourselves a DATA phase interrupt later by setting everything
658 		 * up ahead of time.
659 		 */
660 
661 		if ((cmd->SCp.phase == 0) && (hostdata->no_dma == 0)) {
662 			if (hostdata->dma_setup(cmd,
663 			    (cmd->sc_data_direction == DMA_TO_DEVICE) ?
664 			     DATA_OUT_DIR : DATA_IN_DIR))
665 				write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
666 			else {
667 				write_wd33c93_count(regs,
668 						    cmd->SCp.this_residual);
669 				write_wd33c93(regs, WD_CONTROL,
670 					      CTRL_IDI | CTRL_EDI | hostdata->dma_mode);
671 				hostdata->dma = D_DMA_RUNNING;
672 			}
673 		} else
674 			write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
675 
676 		hostdata->state = S_RUNNING_LEVEL2;
677 		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
678 	}
679 
680 	/*
681 	 * Since the SCSI bus can handle only 1 connection at a time,
682 	 * we get out of here now. If the selection fails, or when
683 	 * the command disconnects, we'll come back to this routine
684 	 * to search the input_Q again...
685 	 */
686 
687 	DB(DB_EXECUTE,
688 	   printk("%s%ld)EX-2 ", (cmd->SCp.phase) ? "d:" : "", cmd->serial_number))
689 }
690 
691 static void
692 transfer_pio(const wd33c93_regs regs, uchar * buf, int cnt,
693 	     int data_in_dir, struct WD33C93_hostdata *hostdata)
694 {
695 	uchar asr;
696 
697 	DB(DB_TRANSFER,
698 	   printk("(%p,%d,%s:", buf, cnt, data_in_dir ? "in" : "out"))
699 
700 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
701 	write_wd33c93_count(regs, cnt);
702 	write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
703 	if (data_in_dir) {
704 		do {
705 			asr = read_aux_stat(regs);
706 			if (asr & ASR_DBR)
707 				*buf++ = read_wd33c93(regs, WD_DATA);
708 		} while (!(asr & ASR_INT));
709 	} else {
710 		do {
711 			asr = read_aux_stat(regs);
712 			if (asr & ASR_DBR)
713 				write_wd33c93(regs, WD_DATA, *buf++);
714 		} while (!(asr & ASR_INT));
715 	}
716 
717 	/* Note: we are returning with the interrupt UN-cleared.
718 	 * Since (presumably) an entire I/O operation has
719 	 * completed, the bus phase is probably different, and
720 	 * the interrupt routine will discover this when it
721 	 * responds to the uncleared int.
722 	 */
723 
724 }
725 
726 static void
727 transfer_bytes(const wd33c93_regs regs, struct scsi_cmnd *cmd,
728 		int data_in_dir)
729 {
730 	struct WD33C93_hostdata *hostdata;
731 	unsigned long length;
732 
733 	hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
734 
735 /* Normally, you'd expect 'this_residual' to be non-zero here.
736  * In a series of scatter-gather transfers, however, this
737  * routine will usually be called with 'this_residual' equal
738  * to 0 and 'buffers_residual' non-zero. This means that a
739  * previous transfer completed, clearing 'this_residual', and
740  * now we need to setup the next scatter-gather buffer as the
741  * source or destination for THIS transfer.
742  */
743 	if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
744 		++cmd->SCp.buffer;
745 		--cmd->SCp.buffers_residual;
746 		cmd->SCp.this_residual = cmd->SCp.buffer->length;
747 		cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
748 	}
749 	if (!cmd->SCp.this_residual) /* avoid bogus setups */
750 		return;
751 
752 	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
753 		      hostdata->sync_xfer[cmd->device->id]);
754 
755 /* 'hostdata->no_dma' is TRUE if we don't even want to try DMA.
756  * Update 'this_residual' and 'ptr' after 'transfer_pio()' returns.
757  */
758 
759 	if (hostdata->no_dma || hostdata->dma_setup(cmd, data_in_dir)) {
760 #ifdef PROC_STATISTICS
761 		hostdata->pio_cnt++;
762 #endif
763 		transfer_pio(regs, (uchar *) cmd->SCp.ptr,
764 			     cmd->SCp.this_residual, data_in_dir, hostdata);
765 		length = cmd->SCp.this_residual;
766 		cmd->SCp.this_residual = read_wd33c93_count(regs);
767 		cmd->SCp.ptr += (length - cmd->SCp.this_residual);
768 	}
769 
770 /* We are able to do DMA (in fact, the Amiga hardware is
771  * already going!), so start up the wd33c93 in DMA mode.
772  * We set 'hostdata->dma' = D_DMA_RUNNING so that when the
773  * transfer completes and causes an interrupt, we're
774  * reminded to tell the Amiga to shut down its end. We'll
775  * postpone the updating of 'this_residual' and 'ptr'
776  * until then.
777  */
778 
779 	else {
780 #ifdef PROC_STATISTICS
781 		hostdata->dma_cnt++;
782 #endif
783 		write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | hostdata->dma_mode);
784 		write_wd33c93_count(regs, cmd->SCp.this_residual);
785 
786 		if ((hostdata->level2 >= L2_DATA) ||
787 		    (hostdata->level2 == L2_BASIC && cmd->SCp.phase == 0)) {
788 			write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
789 			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
790 			hostdata->state = S_RUNNING_LEVEL2;
791 		} else
792 			write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
793 
794 		hostdata->dma = D_DMA_RUNNING;
795 	}
796 }
797 
798 void
799 wd33c93_intr(struct Scsi_Host *instance)
800 {
801 	struct WD33C93_hostdata *hostdata =
802 	    (struct WD33C93_hostdata *) instance->hostdata;
803 	const wd33c93_regs regs = hostdata->regs;
804 	struct scsi_cmnd *patch, *cmd;
805 	uchar asr, sr, phs, id, lun, *ucp, msg;
806 	unsigned long length, flags;
807 
808 	asr = read_aux_stat(regs);
809 	if (!(asr & ASR_INT) || (asr & ASR_BSY))
810 		return;
811 
812 	spin_lock_irqsave(&hostdata->lock, flags);
813 
814 #ifdef PROC_STATISTICS
815 	hostdata->int_cnt++;
816 #endif
817 
818 	cmd = (struct scsi_cmnd *) hostdata->connected;	/* assume we're connected */
819 	sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear the interrupt */
820 	phs = read_wd33c93(regs, WD_COMMAND_PHASE);
821 
822 	DB(DB_INTR, printk("{%02x:%02x-", asr, sr))
823 
824 /* After starting a DMA transfer, the next interrupt
825  * is guaranteed to be in response to completion of
826  * the transfer. Since the Amiga DMA hardware runs in
827  * in an open-ended fashion, it needs to be told when
828  * to stop; do that here if D_DMA_RUNNING is true.
829  * Also, we have to update 'this_residual' and 'ptr'
830  * based on the contents of the TRANSFER_COUNT register,
831  * in case the device decided to do an intermediate
832  * disconnect (a device may do this if it has to do a
833  * seek, or just to be nice and let other devices have
834  * some bus time during long transfers). After doing
835  * whatever is needed, we go on and service the WD3393
836  * interrupt normally.
837  */
838 	    if (hostdata->dma == D_DMA_RUNNING) {
839 		DB(DB_TRANSFER,
840 		   printk("[%p/%d:", cmd->SCp.ptr, cmd->SCp.this_residual))
841 		    hostdata->dma_stop(cmd->device->host, cmd, 1);
842 		hostdata->dma = D_DMA_OFF;
843 		length = cmd->SCp.this_residual;
844 		cmd->SCp.this_residual = read_wd33c93_count(regs);
845 		cmd->SCp.ptr += (length - cmd->SCp.this_residual);
846 		DB(DB_TRANSFER,
847 		   printk("%p/%d]", cmd->SCp.ptr, cmd->SCp.this_residual))
848 	}
849 
850 /* Respond to the specific WD3393 interrupt - there are quite a few! */
851 	switch (sr) {
852 	case CSR_TIMEOUT:
853 		DB(DB_INTR, printk("TIMEOUT"))
854 
855 		    if (hostdata->state == S_RUNNING_LEVEL2)
856 			hostdata->connected = NULL;
857 		else {
858 			cmd = (struct scsi_cmnd *) hostdata->selecting;	/* get a valid cmd */
859 			hostdata->selecting = NULL;
860 		}
861 
862 		cmd->result = DID_NO_CONNECT << 16;
863 		hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
864 		hostdata->state = S_UNCONNECTED;
865 		cmd->scsi_done(cmd);
866 
867 		/* From esp.c:
868 		 * There is a window of time within the scsi_done() path
869 		 * of execution where interrupts are turned back on full
870 		 * blast and left that way.  During that time we could
871 		 * reconnect to a disconnected command, then we'd bomb
872 		 * out below.  We could also end up executing two commands
873 		 * at _once_.  ...just so you know why the restore_flags()
874 		 * is here...
875 		 */
876 
877 		spin_unlock_irqrestore(&hostdata->lock, flags);
878 
879 /* We are not connected to a target - check to see if there
880  * are commands waiting to be executed.
881  */
882 
883 		wd33c93_execute(instance);
884 		break;
885 
886 /* Note: this interrupt should not occur in a LEVEL2 command */
887 
888 	case CSR_SELECT:
889 		DB(DB_INTR, printk("SELECT"))
890 		    hostdata->connected = cmd =
891 		    (struct scsi_cmnd *) hostdata->selecting;
892 		hostdata->selecting = NULL;
893 
894 		/* construct an IDENTIFY message with correct disconnect bit */
895 
896 		hostdata->outgoing_msg[0] = (0x80 | 0x00 | cmd->device->lun);
897 		if (cmd->SCp.phase)
898 			hostdata->outgoing_msg[0] |= 0x40;
899 
900 		if (hostdata->sync_stat[cmd->device->id] == SS_FIRST) {
901 
902 			hostdata->sync_stat[cmd->device->id] = SS_WAITING;
903 
904 /* Tack on a 2nd message to ask about synchronous transfers. If we've
905  * been asked to do only asynchronous transfers on this device, we
906  * request a fifo depth of 0, which is equivalent to async - should
907  * solve the problems some people have had with GVP's Guru ROM.
908  */
909 
910 			hostdata->outgoing_msg[1] = EXTENDED_MESSAGE;
911 			hostdata->outgoing_msg[2] = 3;
912 			hostdata->outgoing_msg[3] = EXTENDED_SDTR;
913 			if (hostdata->no_sync & (1 << cmd->device->id)) {
914 				calc_sync_msg(hostdata->default_sx_per, 0,
915 						0, hostdata->outgoing_msg + 4);
916 			} else {
917 				calc_sync_msg(optimum_sx_per(hostdata),
918 						OPTIMUM_SX_OFF,
919 						hostdata->fast,
920 						hostdata->outgoing_msg + 4);
921 			}
922 			hostdata->outgoing_len = 6;
923 #ifdef SYNC_DEBUG
924 			ucp = hostdata->outgoing_msg + 1;
925 			printk(" sending SDTR %02x03%02x%02x%02x ",
926 				ucp[0], ucp[2], ucp[3], ucp[4]);
927 #endif
928 		} else
929 			hostdata->outgoing_len = 1;
930 
931 		hostdata->state = S_CONNECTED;
932 		spin_unlock_irqrestore(&hostdata->lock, flags);
933 		break;
934 
935 	case CSR_XFER_DONE | PHS_DATA_IN:
936 	case CSR_UNEXP | PHS_DATA_IN:
937 	case CSR_SRV_REQ | PHS_DATA_IN:
938 		DB(DB_INTR,
939 		   printk("IN-%d.%d", cmd->SCp.this_residual,
940 			  cmd->SCp.buffers_residual))
941 		    transfer_bytes(regs, cmd, DATA_IN_DIR);
942 		if (hostdata->state != S_RUNNING_LEVEL2)
943 			hostdata->state = S_CONNECTED;
944 		spin_unlock_irqrestore(&hostdata->lock, flags);
945 		break;
946 
947 	case CSR_XFER_DONE | PHS_DATA_OUT:
948 	case CSR_UNEXP | PHS_DATA_OUT:
949 	case CSR_SRV_REQ | PHS_DATA_OUT:
950 		DB(DB_INTR,
951 		   printk("OUT-%d.%d", cmd->SCp.this_residual,
952 			  cmd->SCp.buffers_residual))
953 		    transfer_bytes(regs, cmd, DATA_OUT_DIR);
954 		if (hostdata->state != S_RUNNING_LEVEL2)
955 			hostdata->state = S_CONNECTED;
956 		spin_unlock_irqrestore(&hostdata->lock, flags);
957 		break;
958 
959 /* Note: this interrupt should not occur in a LEVEL2 command */
960 
961 	case CSR_XFER_DONE | PHS_COMMAND:
962 	case CSR_UNEXP | PHS_COMMAND:
963 	case CSR_SRV_REQ | PHS_COMMAND:
964 		DB(DB_INTR, printk("CMND-%02x,%ld", cmd->cmnd[0], cmd->serial_number))
965 		    transfer_pio(regs, cmd->cmnd, cmd->cmd_len, DATA_OUT_DIR,
966 				 hostdata);
967 		hostdata->state = S_CONNECTED;
968 		spin_unlock_irqrestore(&hostdata->lock, flags);
969 		break;
970 
971 	case CSR_XFER_DONE | PHS_STATUS:
972 	case CSR_UNEXP | PHS_STATUS:
973 	case CSR_SRV_REQ | PHS_STATUS:
974 		DB(DB_INTR, printk("STATUS="))
975 		cmd->SCp.Status = read_1_byte(regs);
976 		DB(DB_INTR, printk("%02x", cmd->SCp.Status))
977 		    if (hostdata->level2 >= L2_BASIC) {
978 			sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear interrupt */
979 			udelay(7);
980 			hostdata->state = S_RUNNING_LEVEL2;
981 			write_wd33c93(regs, WD_COMMAND_PHASE, 0x50);
982 			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
983 		} else {
984 			hostdata->state = S_CONNECTED;
985 		}
986 		spin_unlock_irqrestore(&hostdata->lock, flags);
987 		break;
988 
989 	case CSR_XFER_DONE | PHS_MESS_IN:
990 	case CSR_UNEXP | PHS_MESS_IN:
991 	case CSR_SRV_REQ | PHS_MESS_IN:
992 		DB(DB_INTR, printk("MSG_IN="))
993 
994 		msg = read_1_byte(regs);
995 		sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear interrupt */
996 		udelay(7);
997 
998 		hostdata->incoming_msg[hostdata->incoming_ptr] = msg;
999 		if (hostdata->incoming_msg[0] == EXTENDED_MESSAGE)
1000 			msg = EXTENDED_MESSAGE;
1001 		else
1002 			hostdata->incoming_ptr = 0;
1003 
1004 		cmd->SCp.Message = msg;
1005 		switch (msg) {
1006 
1007 		case COMMAND_COMPLETE:
1008 			DB(DB_INTR, printk("CCMP-%ld", cmd->serial_number))
1009 			    write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1010 			hostdata->state = S_PRE_CMP_DISC;
1011 			break;
1012 
1013 		case SAVE_POINTERS:
1014 			DB(DB_INTR, printk("SDP"))
1015 			    write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1016 			hostdata->state = S_CONNECTED;
1017 			break;
1018 
1019 		case RESTORE_POINTERS:
1020 			DB(DB_INTR, printk("RDP"))
1021 			    if (hostdata->level2 >= L2_BASIC) {
1022 				write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
1023 				write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
1024 				hostdata->state = S_RUNNING_LEVEL2;
1025 			} else {
1026 				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1027 				hostdata->state = S_CONNECTED;
1028 			}
1029 			break;
1030 
1031 		case DISCONNECT:
1032 			DB(DB_INTR, printk("DIS"))
1033 			    cmd->device->disconnect = 1;
1034 			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1035 			hostdata->state = S_PRE_TMP_DISC;
1036 			break;
1037 
1038 		case MESSAGE_REJECT:
1039 			DB(DB_INTR, printk("REJ"))
1040 #ifdef SYNC_DEBUG
1041 			    printk("-REJ-");
1042 #endif
1043 			if (hostdata->sync_stat[cmd->device->id] == SS_WAITING) {
1044 				hostdata->sync_stat[cmd->device->id] = SS_SET;
1045 				/* we want default_sx_per, not DEFAULT_SX_PER */
1046 				hostdata->sync_xfer[cmd->device->id] =
1047 					calc_sync_xfer(hostdata->default_sx_per
1048 						/ 4, 0, 0, hostdata->sx_table);
1049 			}
1050 			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1051 			hostdata->state = S_CONNECTED;
1052 			break;
1053 
1054 		case EXTENDED_MESSAGE:
1055 			DB(DB_INTR, printk("EXT"))
1056 
1057 			    ucp = hostdata->incoming_msg;
1058 
1059 #ifdef SYNC_DEBUG
1060 			printk("%02x", ucp[hostdata->incoming_ptr]);
1061 #endif
1062 			/* Is this the last byte of the extended message? */
1063 
1064 			if ((hostdata->incoming_ptr >= 2) &&
1065 			    (hostdata->incoming_ptr == (ucp[1] + 1))) {
1066 
1067 				switch (ucp[2]) {	/* what's the EXTENDED code? */
1068 				case EXTENDED_SDTR:
1069 					/* default to default async period */
1070 					id = calc_sync_xfer(hostdata->
1071 							default_sx_per / 4, 0,
1072 							0, hostdata->sx_table);
1073 					if (hostdata->sync_stat[cmd->device->id] !=
1074 					    SS_WAITING) {
1075 
1076 /* A device has sent an unsolicited SDTR message; rather than go
1077  * through the effort of decoding it and then figuring out what
1078  * our reply should be, we're just gonna say that we have a
1079  * synchronous fifo depth of 0. This will result in asynchronous
1080  * transfers - not ideal but so much easier.
1081  * Actually, this is OK because it assures us that if we don't
1082  * specifically ask for sync transfers, we won't do any.
1083  */
1084 
1085 						write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1086 						hostdata->outgoing_msg[0] =
1087 						    EXTENDED_MESSAGE;
1088 						hostdata->outgoing_msg[1] = 3;
1089 						hostdata->outgoing_msg[2] =
1090 						    EXTENDED_SDTR;
1091 						calc_sync_msg(hostdata->
1092 							default_sx_per, 0,
1093 							0, hostdata->outgoing_msg + 3);
1094 						hostdata->outgoing_len = 5;
1095 					} else {
1096 						if (ucp[4]) /* well, sync transfer */
1097 							id = calc_sync_xfer(ucp[3], ucp[4],
1098 									hostdata->fast,
1099 									hostdata->sx_table);
1100 						else if (ucp[3]) /* very unlikely... */
1101 							id = calc_sync_xfer(ucp[3], ucp[4],
1102 									0, hostdata->sx_table);
1103 					}
1104 					hostdata->sync_xfer[cmd->device->id] = id;
1105 #ifdef SYNC_DEBUG
1106 					printk(" sync_xfer=%02x\n",
1107 					       hostdata->sync_xfer[cmd->device->id]);
1108 #endif
1109 					hostdata->sync_stat[cmd->device->id] =
1110 					    SS_SET;
1111 					write_wd33c93_cmd(regs,
1112 							  WD_CMD_NEGATE_ACK);
1113 					hostdata->state = S_CONNECTED;
1114 					break;
1115 				case EXTENDED_WDTR:
1116 					write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1117 					printk("sending WDTR ");
1118 					hostdata->outgoing_msg[0] =
1119 					    EXTENDED_MESSAGE;
1120 					hostdata->outgoing_msg[1] = 2;
1121 					hostdata->outgoing_msg[2] =
1122 					    EXTENDED_WDTR;
1123 					hostdata->outgoing_msg[3] = 0;	/* 8 bit transfer width */
1124 					hostdata->outgoing_len = 4;
1125 					write_wd33c93_cmd(regs,
1126 							  WD_CMD_NEGATE_ACK);
1127 					hostdata->state = S_CONNECTED;
1128 					break;
1129 				default:
1130 					write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1131 					printk
1132 					    ("Rejecting Unknown Extended Message(%02x). ",
1133 					     ucp[2]);
1134 					hostdata->outgoing_msg[0] =
1135 					    MESSAGE_REJECT;
1136 					hostdata->outgoing_len = 1;
1137 					write_wd33c93_cmd(regs,
1138 							  WD_CMD_NEGATE_ACK);
1139 					hostdata->state = S_CONNECTED;
1140 					break;
1141 				}
1142 				hostdata->incoming_ptr = 0;
1143 			}
1144 
1145 			/* We need to read more MESS_IN bytes for the extended message */
1146 
1147 			else {
1148 				hostdata->incoming_ptr++;
1149 				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1150 				hostdata->state = S_CONNECTED;
1151 			}
1152 			break;
1153 
1154 		default:
1155 			printk("Rejecting Unknown Message(%02x) ", msg);
1156 			write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1157 			hostdata->outgoing_msg[0] = MESSAGE_REJECT;
1158 			hostdata->outgoing_len = 1;
1159 			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1160 			hostdata->state = S_CONNECTED;
1161 		}
1162 		spin_unlock_irqrestore(&hostdata->lock, flags);
1163 		break;
1164 
1165 /* Note: this interrupt will occur only after a LEVEL2 command */
1166 
1167 	case CSR_SEL_XFER_DONE:
1168 
1169 /* Make sure that reselection is enabled at this point - it may
1170  * have been turned off for the command that just completed.
1171  */
1172 
1173 		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
1174 		if (phs == 0x60) {
1175 			DB(DB_INTR, printk("SX-DONE-%ld", cmd->serial_number))
1176 			    cmd->SCp.Message = COMMAND_COMPLETE;
1177 			lun = read_wd33c93(regs, WD_TARGET_LUN);
1178 			DB(DB_INTR, printk(":%d.%d", cmd->SCp.Status, lun))
1179 			    hostdata->connected = NULL;
1180 			hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
1181 			hostdata->state = S_UNCONNECTED;
1182 			if (cmd->SCp.Status == ILLEGAL_STATUS_BYTE)
1183 				cmd->SCp.Status = lun;
1184 			if (cmd->cmnd[0] == REQUEST_SENSE
1185 			    && cmd->SCp.Status != GOOD)
1186 				cmd->result =
1187 				    (cmd->
1188 				     result & 0x00ffff) | (DID_ERROR << 16);
1189 			else
1190 				cmd->result =
1191 				    cmd->SCp.Status | (cmd->SCp.Message << 8);
1192 			cmd->scsi_done(cmd);
1193 
1194 /* We are no longer  connected to a target - check to see if
1195  * there are commands waiting to be executed.
1196  */
1197 			spin_unlock_irqrestore(&hostdata->lock, flags);
1198 			wd33c93_execute(instance);
1199 		} else {
1200 			printk
1201 			    ("%02x:%02x:%02x-%ld: Unknown SEL_XFER_DONE phase!!---",
1202 			     asr, sr, phs, cmd->serial_number);
1203 			spin_unlock_irqrestore(&hostdata->lock, flags);
1204 		}
1205 		break;
1206 
1207 /* Note: this interrupt will occur only after a LEVEL2 command */
1208 
1209 	case CSR_SDP:
1210 		DB(DB_INTR, printk("SDP"))
1211 		    hostdata->state = S_RUNNING_LEVEL2;
1212 		write_wd33c93(regs, WD_COMMAND_PHASE, 0x41);
1213 		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
1214 		spin_unlock_irqrestore(&hostdata->lock, flags);
1215 		break;
1216 
1217 	case CSR_XFER_DONE | PHS_MESS_OUT:
1218 	case CSR_UNEXP | PHS_MESS_OUT:
1219 	case CSR_SRV_REQ | PHS_MESS_OUT:
1220 		DB(DB_INTR, printk("MSG_OUT="))
1221 
1222 /* To get here, we've probably requested MESSAGE_OUT and have
1223  * already put the correct bytes in outgoing_msg[] and filled
1224  * in outgoing_len. We simply send them out to the SCSI bus.
1225  * Sometimes we get MESSAGE_OUT phase when we're not expecting
1226  * it - like when our SDTR message is rejected by a target. Some
1227  * targets send the REJECT before receiving all of the extended
1228  * message, and then seem to go back to MESSAGE_OUT for a byte
1229  * or two. Not sure why, or if I'm doing something wrong to
1230  * cause this to happen. Regardless, it seems that sending
1231  * NOP messages in these situations results in no harm and
1232  * makes everyone happy.
1233  */
1234 		    if (hostdata->outgoing_len == 0) {
1235 			hostdata->outgoing_len = 1;
1236 			hostdata->outgoing_msg[0] = NOP;
1237 		}
1238 		transfer_pio(regs, hostdata->outgoing_msg,
1239 			     hostdata->outgoing_len, DATA_OUT_DIR, hostdata);
1240 		DB(DB_INTR, printk("%02x", hostdata->outgoing_msg[0]))
1241 		    hostdata->outgoing_len = 0;
1242 		hostdata->state = S_CONNECTED;
1243 		spin_unlock_irqrestore(&hostdata->lock, flags);
1244 		break;
1245 
1246 	case CSR_UNEXP_DISC:
1247 
1248 /* I think I've seen this after a request-sense that was in response
1249  * to an error condition, but not sure. We certainly need to do
1250  * something when we get this interrupt - the question is 'what?'.
1251  * Let's think positively, and assume some command has finished
1252  * in a legal manner (like a command that provokes a request-sense),
1253  * so we treat it as a normal command-complete-disconnect.
1254  */
1255 
1256 /* Make sure that reselection is enabled at this point - it may
1257  * have been turned off for the command that just completed.
1258  */
1259 
1260 		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
1261 		if (cmd == NULL) {
1262 			printk(" - Already disconnected! ");
1263 			hostdata->state = S_UNCONNECTED;
1264 			spin_unlock_irqrestore(&hostdata->lock, flags);
1265 			return;
1266 		}
1267 		DB(DB_INTR, printk("UNEXP_DISC-%ld", cmd->serial_number))
1268 		    hostdata->connected = NULL;
1269 		hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
1270 		hostdata->state = S_UNCONNECTED;
1271 		if (cmd->cmnd[0] == REQUEST_SENSE && cmd->SCp.Status != GOOD)
1272 			cmd->result =
1273 			    (cmd->result & 0x00ffff) | (DID_ERROR << 16);
1274 		else
1275 			cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
1276 		cmd->scsi_done(cmd);
1277 
1278 /* We are no longer connected to a target - check to see if
1279  * there are commands waiting to be executed.
1280  */
1281 		/* look above for comments on scsi_done() */
1282 		spin_unlock_irqrestore(&hostdata->lock, flags);
1283 		wd33c93_execute(instance);
1284 		break;
1285 
1286 	case CSR_DISC:
1287 
1288 /* Make sure that reselection is enabled at this point - it may
1289  * have been turned off for the command that just completed.
1290  */
1291 
1292 		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
1293 		DB(DB_INTR, printk("DISC-%ld", cmd->serial_number))
1294 		    if (cmd == NULL) {
1295 			printk(" - Already disconnected! ");
1296 			hostdata->state = S_UNCONNECTED;
1297 		}
1298 		switch (hostdata->state) {
1299 		case S_PRE_CMP_DISC:
1300 			hostdata->connected = NULL;
1301 			hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
1302 			hostdata->state = S_UNCONNECTED;
1303 			DB(DB_INTR, printk(":%d", cmd->SCp.Status))
1304 			    if (cmd->cmnd[0] == REQUEST_SENSE
1305 				&& cmd->SCp.Status != GOOD)
1306 				cmd->result =
1307 				    (cmd->
1308 				     result & 0x00ffff) | (DID_ERROR << 16);
1309 			else
1310 				cmd->result =
1311 				    cmd->SCp.Status | (cmd->SCp.Message << 8);
1312 			cmd->scsi_done(cmd);
1313 			break;
1314 		case S_PRE_TMP_DISC:
1315 		case S_RUNNING_LEVEL2:
1316 			cmd->host_scribble = (uchar *) hostdata->disconnected_Q;
1317 			hostdata->disconnected_Q = cmd;
1318 			hostdata->connected = NULL;
1319 			hostdata->state = S_UNCONNECTED;
1320 
1321 #ifdef PROC_STATISTICS
1322 			hostdata->disc_done_cnt[cmd->device->id]++;
1323 #endif
1324 
1325 			break;
1326 		default:
1327 			printk("*** Unexpected DISCONNECT interrupt! ***");
1328 			hostdata->state = S_UNCONNECTED;
1329 		}
1330 
1331 /* We are no longer connected to a target - check to see if
1332  * there are commands waiting to be executed.
1333  */
1334 		spin_unlock_irqrestore(&hostdata->lock, flags);
1335 		wd33c93_execute(instance);
1336 		break;
1337 
1338 	case CSR_RESEL_AM:
1339 	case CSR_RESEL:
1340 		DB(DB_INTR, printk("RESEL%s", sr == CSR_RESEL_AM ? "_AM" : ""))
1341 
1342 		    /* Old chips (pre -A ???) don't have advanced features and will
1343 		     * generate CSR_RESEL.  In that case we have to extract the LUN the
1344 		     * hard way (see below).
1345 		     * First we have to make sure this reselection didn't
1346 		     * happen during Arbitration/Selection of some other device.
1347 		     * If yes, put losing command back on top of input_Q.
1348 		     */
1349 		    if (hostdata->level2 <= L2_NONE) {
1350 
1351 			if (hostdata->selecting) {
1352 				cmd = (struct scsi_cmnd *) hostdata->selecting;
1353 				hostdata->selecting = NULL;
1354 				hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
1355 				cmd->host_scribble =
1356 				    (uchar *) hostdata->input_Q;
1357 				hostdata->input_Q = cmd;
1358 			}
1359 		}
1360 
1361 		else {
1362 
1363 			if (cmd) {
1364 				if (phs == 0x00) {
1365 					hostdata->busy[cmd->device->id] &=
1366 					    ~(1 << cmd->device->lun);
1367 					cmd->host_scribble =
1368 					    (uchar *) hostdata->input_Q;
1369 					hostdata->input_Q = cmd;
1370 				} else {
1371 					printk
1372 					    ("---%02x:%02x:%02x-TROUBLE: Intrusive ReSelect!---",
1373 					     asr, sr, phs);
1374 					while (1)
1375 						printk("\r");
1376 				}
1377 			}
1378 
1379 		}
1380 
1381 		/* OK - find out which device reselected us. */
1382 
1383 		id = read_wd33c93(regs, WD_SOURCE_ID);
1384 		id &= SRCID_MASK;
1385 
1386 		/* and extract the lun from the ID message. (Note that we don't
1387 		 * bother to check for a valid message here - I guess this is
1388 		 * not the right way to go, but...)
1389 		 */
1390 
1391 		if (sr == CSR_RESEL_AM) {
1392 			lun = read_wd33c93(regs, WD_DATA);
1393 			if (hostdata->level2 < L2_RESELECT)
1394 				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1395 			lun &= 7;
1396 		} else {
1397 			/* Old chip; wait for msgin phase to pick up the LUN. */
1398 			for (lun = 255; lun; lun--) {
1399 				if ((asr = read_aux_stat(regs)) & ASR_INT)
1400 					break;
1401 				udelay(10);
1402 			}
1403 			if (!(asr & ASR_INT)) {
1404 				printk
1405 				    ("wd33c93: Reselected without IDENTIFY\n");
1406 				lun = 0;
1407 			} else {
1408 				/* Verify this is a change to MSG_IN and read the message */
1409 				sr = read_wd33c93(regs, WD_SCSI_STATUS);
1410 				udelay(7);
1411 				if (sr == (CSR_ABORT | PHS_MESS_IN) ||
1412 				    sr == (CSR_UNEXP | PHS_MESS_IN) ||
1413 				    sr == (CSR_SRV_REQ | PHS_MESS_IN)) {
1414 					/* Got MSG_IN, grab target LUN */
1415 					lun = read_1_byte(regs);
1416 					/* Now we expect a 'paused with ACK asserted' int.. */
1417 					asr = read_aux_stat(regs);
1418 					if (!(asr & ASR_INT)) {
1419 						udelay(10);
1420 						asr = read_aux_stat(regs);
1421 						if (!(asr & ASR_INT))
1422 							printk
1423 							    ("wd33c93: No int after LUN on RESEL (%02x)\n",
1424 							     asr);
1425 					}
1426 					sr = read_wd33c93(regs, WD_SCSI_STATUS);
1427 					udelay(7);
1428 					if (sr != CSR_MSGIN)
1429 						printk
1430 						    ("wd33c93: Not paused with ACK on RESEL (%02x)\n",
1431 						     sr);
1432 					lun &= 7;
1433 					write_wd33c93_cmd(regs,
1434 							  WD_CMD_NEGATE_ACK);
1435 				} else {
1436 					printk
1437 					    ("wd33c93: Not MSG_IN on reselect (%02x)\n",
1438 					     sr);
1439 					lun = 0;
1440 				}
1441 			}
1442 		}
1443 
1444 		/* Now we look for the command that's reconnecting. */
1445 
1446 		cmd = (struct scsi_cmnd *) hostdata->disconnected_Q;
1447 		patch = NULL;
1448 		while (cmd) {
1449 			if (id == cmd->device->id && lun == cmd->device->lun)
1450 				break;
1451 			patch = cmd;
1452 			cmd = (struct scsi_cmnd *) cmd->host_scribble;
1453 		}
1454 
1455 		/* Hmm. Couldn't find a valid command.... What to do? */
1456 
1457 		if (!cmd) {
1458 			printk
1459 			    ("---TROUBLE: target %d.%d not in disconnect queue---",
1460 			     id, lun);
1461 			spin_unlock_irqrestore(&hostdata->lock, flags);
1462 			return;
1463 		}
1464 
1465 		/* Ok, found the command - now start it up again. */
1466 
1467 		if (patch)
1468 			patch->host_scribble = cmd->host_scribble;
1469 		else
1470 			hostdata->disconnected_Q =
1471 			    (struct scsi_cmnd *) cmd->host_scribble;
1472 		hostdata->connected = cmd;
1473 
1474 		/* We don't need to worry about 'initialize_SCp()' or 'hostdata->busy[]'
1475 		 * because these things are preserved over a disconnect.
1476 		 * But we DO need to fix the DPD bit so it's correct for this command.
1477 		 */
1478 
1479 		if (cmd->sc_data_direction == DMA_TO_DEVICE)
1480 			write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
1481 		else
1482 			write_wd33c93(regs, WD_DESTINATION_ID,
1483 				      cmd->device->id | DSTID_DPD);
1484 		if (hostdata->level2 >= L2_RESELECT) {
1485 			write_wd33c93_count(regs, 0);	/* we want a DATA_PHASE interrupt */
1486 			write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
1487 			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
1488 			hostdata->state = S_RUNNING_LEVEL2;
1489 		} else
1490 			hostdata->state = S_CONNECTED;
1491 
1492 		DB(DB_INTR, printk("-%ld", cmd->serial_number))
1493 		    spin_unlock_irqrestore(&hostdata->lock, flags);
1494 		break;
1495 
1496 	default:
1497 		printk("--UNKNOWN INTERRUPT:%02x:%02x:%02x--", asr, sr, phs);
1498 		spin_unlock_irqrestore(&hostdata->lock, flags);
1499 	}
1500 
1501 	DB(DB_INTR, printk("} "))
1502 
1503 }
1504 
1505 static void
1506 reset_wd33c93(struct Scsi_Host *instance)
1507 {
1508 	struct WD33C93_hostdata *hostdata =
1509 	    (struct WD33C93_hostdata *) instance->hostdata;
1510 	const wd33c93_regs regs = hostdata->regs;
1511 	uchar sr;
1512 
1513 #ifdef CONFIG_SGI_IP22
1514 	{
1515 		int busycount = 0;
1516 		extern void sgiwd93_reset(unsigned long);
1517 		/* wait 'til the chip gets some time for us */
1518 		while ((read_aux_stat(regs) & ASR_BSY) && busycount++ < 100)
1519 			udelay (10);
1520 	/*
1521  	 * there are scsi devices out there, which manage to lock up
1522 	 * the wd33c93 in a busy condition. In this state it won't
1523 	 * accept the reset command. The only way to solve this is to
1524  	 * give the chip a hardware reset (if possible). The code below
1525 	 * does this for the SGI Indy, where this is possible
1526 	 */
1527 	/* still busy ? */
1528 	if (read_aux_stat(regs) & ASR_BSY)
1529 		sgiwd93_reset(instance->base); /* yeah, give it the hard one */
1530 	}
1531 #endif
1532 
1533 	write_wd33c93(regs, WD_OWN_ID, OWNID_EAF | OWNID_RAF |
1534 		      instance->this_id | hostdata->clock_freq);
1535 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
1536 	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
1537 		      calc_sync_xfer(hostdata->default_sx_per / 4,
1538 				     DEFAULT_SX_OFF, 0, hostdata->sx_table));
1539 	write_wd33c93(regs, WD_COMMAND, WD_CMD_RESET);
1540 
1541 
1542 #ifdef CONFIG_MVME147_SCSI
1543 	udelay(25);		/* The old wd33c93 on MVME147 needs this, at least */
1544 #endif
1545 
1546 	while (!(read_aux_stat(regs) & ASR_INT))
1547 		;
1548 	sr = read_wd33c93(regs, WD_SCSI_STATUS);
1549 
1550 	hostdata->microcode = read_wd33c93(regs, WD_CDB_1);
1551 	if (sr == 0x00)
1552 		hostdata->chip = C_WD33C93;
1553 	else if (sr == 0x01) {
1554 		write_wd33c93(regs, WD_QUEUE_TAG, 0xa5);	/* any random number */
1555 		sr = read_wd33c93(regs, WD_QUEUE_TAG);
1556 		if (sr == 0xa5) {
1557 			hostdata->chip = C_WD33C93B;
1558 			write_wd33c93(regs, WD_QUEUE_TAG, 0);
1559 		} else
1560 			hostdata->chip = C_WD33C93A;
1561 	} else
1562 		hostdata->chip = C_UNKNOWN_CHIP;
1563 
1564 	if (hostdata->chip != C_WD33C93B)	/* Fast SCSI unavailable */
1565 		hostdata->fast = 0;
1566 
1567 	write_wd33c93(regs, WD_TIMEOUT_PERIOD, TIMEOUT_PERIOD_VALUE);
1568 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
1569 }
1570 
1571 int
1572 wd33c93_host_reset(struct scsi_cmnd * SCpnt)
1573 {
1574 	struct Scsi_Host *instance;
1575 	struct WD33C93_hostdata *hostdata;
1576 	int i;
1577 
1578 	instance = SCpnt->device->host;
1579 	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1580 
1581 	printk("scsi%d: reset. ", instance->host_no);
1582 	disable_irq(instance->irq);
1583 
1584 	hostdata->dma_stop(instance, NULL, 0);
1585 	for (i = 0; i < 8; i++) {
1586 		hostdata->busy[i] = 0;
1587 		hostdata->sync_xfer[i] =
1588 			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
1589 					0, hostdata->sx_table);
1590 		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
1591 	}
1592 	hostdata->input_Q = NULL;
1593 	hostdata->selecting = NULL;
1594 	hostdata->connected = NULL;
1595 	hostdata->disconnected_Q = NULL;
1596 	hostdata->state = S_UNCONNECTED;
1597 	hostdata->dma = D_DMA_OFF;
1598 	hostdata->incoming_ptr = 0;
1599 	hostdata->outgoing_len = 0;
1600 
1601 	reset_wd33c93(instance);
1602 	SCpnt->result = DID_RESET << 16;
1603 	enable_irq(instance->irq);
1604 	return SUCCESS;
1605 }
1606 
1607 int
1608 wd33c93_abort(struct scsi_cmnd * cmd)
1609 {
1610 	struct Scsi_Host *instance;
1611 	struct WD33C93_hostdata *hostdata;
1612 	wd33c93_regs regs;
1613 	struct scsi_cmnd *tmp, *prev;
1614 
1615 	disable_irq(cmd->device->host->irq);
1616 
1617 	instance = cmd->device->host;
1618 	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1619 	regs = hostdata->regs;
1620 
1621 /*
1622  * Case 1 : If the command hasn't been issued yet, we simply remove it
1623  *     from the input_Q.
1624  */
1625 
1626 	tmp = (struct scsi_cmnd *) hostdata->input_Q;
1627 	prev = NULL;
1628 	while (tmp) {
1629 		if (tmp == cmd) {
1630 			if (prev)
1631 				prev->host_scribble = cmd->host_scribble;
1632 			else
1633 				hostdata->input_Q =
1634 				    (struct scsi_cmnd *) cmd->host_scribble;
1635 			cmd->host_scribble = NULL;
1636 			cmd->result = DID_ABORT << 16;
1637 			printk
1638 			    ("scsi%d: Abort - removing command %ld from input_Q. ",
1639 			     instance->host_no, cmd->serial_number);
1640 			enable_irq(cmd->device->host->irq);
1641 			cmd->scsi_done(cmd);
1642 			return SUCCESS;
1643 		}
1644 		prev = tmp;
1645 		tmp = (struct scsi_cmnd *) tmp->host_scribble;
1646 	}
1647 
1648 /*
1649  * Case 2 : If the command is connected, we're going to fail the abort
1650  *     and let the high level SCSI driver retry at a later time or
1651  *     issue a reset.
1652  *
1653  *     Timeouts, and therefore aborted commands, will be highly unlikely
1654  *     and handling them cleanly in this situation would make the common
1655  *     case of noresets less efficient, and would pollute our code.  So,
1656  *     we fail.
1657  */
1658 
1659 	if (hostdata->connected == cmd) {
1660 		uchar sr, asr;
1661 		unsigned long timeout;
1662 
1663 		printk("scsi%d: Aborting connected command %ld - ",
1664 		       instance->host_no, cmd->serial_number);
1665 
1666 		printk("stopping DMA - ");
1667 		if (hostdata->dma == D_DMA_RUNNING) {
1668 			hostdata->dma_stop(instance, cmd, 0);
1669 			hostdata->dma = D_DMA_OFF;
1670 		}
1671 
1672 		printk("sending wd33c93 ABORT command - ");
1673 		write_wd33c93(regs, WD_CONTROL,
1674 			      CTRL_IDI | CTRL_EDI | CTRL_POLLED);
1675 		write_wd33c93_cmd(regs, WD_CMD_ABORT);
1676 
1677 /* Now we have to attempt to flush out the FIFO... */
1678 
1679 		printk("flushing fifo - ");
1680 		timeout = 1000000;
1681 		do {
1682 			asr = read_aux_stat(regs);
1683 			if (asr & ASR_DBR)
1684 				read_wd33c93(regs, WD_DATA);
1685 		} while (!(asr & ASR_INT) && timeout-- > 0);
1686 		sr = read_wd33c93(regs, WD_SCSI_STATUS);
1687 		printk
1688 		    ("asr=%02x, sr=%02x, %ld bytes un-transferred (timeout=%ld) - ",
1689 		     asr, sr, read_wd33c93_count(regs), timeout);
1690 
1691 		/*
1692 		 * Abort command processed.
1693 		 * Still connected.
1694 		 * We must disconnect.
1695 		 */
1696 
1697 		printk("sending wd33c93 DISCONNECT command - ");
1698 		write_wd33c93_cmd(regs, WD_CMD_DISCONNECT);
1699 
1700 		timeout = 1000000;
1701 		asr = read_aux_stat(regs);
1702 		while ((asr & ASR_CIP) && timeout-- > 0)
1703 			asr = read_aux_stat(regs);
1704 		sr = read_wd33c93(regs, WD_SCSI_STATUS);
1705 		printk("asr=%02x, sr=%02x.", asr, sr);
1706 
1707 		hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
1708 		hostdata->connected = NULL;
1709 		hostdata->state = S_UNCONNECTED;
1710 		cmd->result = DID_ABORT << 16;
1711 
1712 /*      sti();*/
1713 		wd33c93_execute(instance);
1714 
1715 		enable_irq(cmd->device->host->irq);
1716 		cmd->scsi_done(cmd);
1717 		return SUCCESS;
1718 	}
1719 
1720 /*
1721  * Case 3: If the command is currently disconnected from the bus,
1722  * we're not going to expend much effort here: Let's just return
1723  * an ABORT_SNOOZE and hope for the best...
1724  */
1725 
1726 	tmp = (struct scsi_cmnd *) hostdata->disconnected_Q;
1727 	while (tmp) {
1728 		if (tmp == cmd) {
1729 			printk
1730 			    ("scsi%d: Abort - command %ld found on disconnected_Q - ",
1731 			     instance->host_no, cmd->serial_number);
1732 			printk("Abort SNOOZE. ");
1733 			enable_irq(cmd->device->host->irq);
1734 			return FAILED;
1735 		}
1736 		tmp = (struct scsi_cmnd *) tmp->host_scribble;
1737 	}
1738 
1739 /*
1740  * Case 4 : If we reached this point, the command was not found in any of
1741  *     the queues.
1742  *
1743  * We probably reached this point because of an unlikely race condition
1744  * between the command completing successfully and the abortion code,
1745  * so we won't panic, but we will notify the user in case something really
1746  * broke.
1747  */
1748 
1749 /*   sti();*/
1750 	wd33c93_execute(instance);
1751 
1752 	enable_irq(cmd->device->host->irq);
1753 	printk("scsi%d: warning : SCSI command probably completed successfully"
1754 	       "         before abortion. ", instance->host_no);
1755 	return FAILED;
1756 }
1757 
1758 #define MAX_WD33C93_HOSTS 4
1759 #define MAX_SETUP_ARGS ARRAY_SIZE(setup_args)
1760 #define SETUP_BUFFER_SIZE 200
1761 static char setup_buffer[SETUP_BUFFER_SIZE];
1762 static char setup_used[MAX_SETUP_ARGS];
1763 static int done_setup = 0;
1764 
1765 static int
1766 wd33c93_setup(char *str)
1767 {
1768 	int i;
1769 	char *p1, *p2;
1770 
1771 	/* The kernel does some processing of the command-line before calling
1772 	 * this function: If it begins with any decimal or hex number arguments,
1773 	 * ints[0] = how many numbers found and ints[1] through [n] are the values
1774 	 * themselves. str points to where the non-numeric arguments (if any)
1775 	 * start: We do our own parsing of those. We construct synthetic 'nosync'
1776 	 * keywords out of numeric args (to maintain compatibility with older
1777 	 * versions) and then add the rest of the arguments.
1778 	 */
1779 
1780 	p1 = setup_buffer;
1781 	*p1 = '\0';
1782 	if (str)
1783 		strncpy(p1, str, SETUP_BUFFER_SIZE - strlen(setup_buffer));
1784 	setup_buffer[SETUP_BUFFER_SIZE - 1] = '\0';
1785 	p1 = setup_buffer;
1786 	i = 0;
1787 	while (*p1 && (i < MAX_SETUP_ARGS)) {
1788 		p2 = strchr(p1, ',');
1789 		if (p2) {
1790 			*p2 = '\0';
1791 			if (p1 != p2)
1792 				setup_args[i] = p1;
1793 			p1 = p2 + 1;
1794 			i++;
1795 		} else {
1796 			setup_args[i] = p1;
1797 			break;
1798 		}
1799 	}
1800 	for (i = 0; i < MAX_SETUP_ARGS; i++)
1801 		setup_used[i] = 0;
1802 	done_setup = 1;
1803 
1804 	return 1;
1805 }
1806 __setup("wd33c93=", wd33c93_setup);
1807 
1808 /* check_setup_args() returns index if key found, 0 if not
1809  */
1810 static int
1811 check_setup_args(char *key, int *flags, int *val, char *buf)
1812 {
1813 	int x;
1814 	char *cp;
1815 
1816 	for (x = 0; x < MAX_SETUP_ARGS; x++) {
1817 		if (setup_used[x])
1818 			continue;
1819 		if (!strncmp(setup_args[x], key, strlen(key)))
1820 			break;
1821 		if (!strncmp(setup_args[x], "next", strlen("next")))
1822 			return 0;
1823 	}
1824 	if (x == MAX_SETUP_ARGS)
1825 		return 0;
1826 	setup_used[x] = 1;
1827 	cp = setup_args[x] + strlen(key);
1828 	*val = -1;
1829 	if (*cp != ':')
1830 		return ++x;
1831 	cp++;
1832 	if ((*cp >= '0') && (*cp <= '9')) {
1833 		*val = simple_strtoul(cp, NULL, 0);
1834 	}
1835 	return ++x;
1836 }
1837 
1838 /*
1839  * Calculate internal data-transfer-clock cycle from input-clock
1840  * frequency (/MHz) and fill 'sx_table'.
1841  *
1842  * The original driver used to rely on a fixed sx_table, containing periods
1843  * for (only) the lower limits of the respective input-clock-frequency ranges
1844  * (8-10/12-15/16-20 MHz). Although it seems, that no problems ocurred with
1845  * this setting so far, it might be desirable to adjust the transfer periods
1846  * closer to the really attached, possibly 25% higher, input-clock, since
1847  * - the wd33c93 may really use a significant shorter period, than it has
1848  *   negotiated (eg. thrashing the target, which expects 4/8MHz, with 5/10MHz
1849  *   instead).
1850  * - the wd33c93 may ask the target for a lower transfer rate, than the target
1851  *   is capable of (eg. negotiating for an assumed minimum of 252ns instead of
1852  *   possible 200ns, which indeed shows up in tests as an approx. 10% lower
1853  *   transfer rate).
1854  */
1855 static inline unsigned int
1856 round_4(unsigned int x)
1857 {
1858 	switch (x & 3) {
1859 		case 1: --x;
1860 			break;
1861 		case 2: ++x;
1862 		case 3: ++x;
1863 	}
1864 	return x;
1865 }
1866 
1867 static void
1868 calc_sx_table(unsigned int mhz, struct sx_period sx_table[9])
1869 {
1870 	unsigned int d, i;
1871 	if (mhz < 11)
1872 		d = 2;	/* divisor for  8-10 MHz input-clock */
1873 	else if (mhz < 16)
1874 		d = 3;	/* divisor for 12-15 MHz input-clock */
1875 	else
1876 		d = 4;	/* divisor for 16-20 MHz input-clock */
1877 
1878 	d = (100000 * d) / 2 / mhz; /* 100 x DTCC / nanosec */
1879 
1880 	sx_table[0].period_ns = 1;
1881 	sx_table[0].reg_value = 0x20;
1882 	for (i = 1; i < 8; i++) {
1883 		sx_table[i].period_ns = round_4((i+1)*d / 100);
1884 		sx_table[i].reg_value = (i+1)*0x10;
1885 	}
1886 	sx_table[7].reg_value = 0;
1887 	sx_table[8].period_ns = 0;
1888 	sx_table[8].reg_value = 0;
1889 }
1890 
1891 /*
1892  * check and, maybe, map an init- or "clock:"- argument.
1893  */
1894 static uchar
1895 set_clk_freq(int freq, int *mhz)
1896 {
1897 	int x = freq;
1898 	if (WD33C93_FS_8_10 == freq)
1899 		freq = 8;
1900 	else if (WD33C93_FS_12_15 == freq)
1901 		freq = 12;
1902 	else if (WD33C93_FS_16_20 == freq)
1903 		freq = 16;
1904 	else if (freq > 7 && freq < 11)
1905 		x = WD33C93_FS_8_10;
1906 		else if (freq > 11 && freq < 16)
1907 		x = WD33C93_FS_12_15;
1908 		else if (freq > 15 && freq < 21)
1909 		x = WD33C93_FS_16_20;
1910 	else {
1911 			/* Hmm, wouldn't it be safer to assume highest freq here? */
1912 		x = WD33C93_FS_8_10;
1913 		freq = 8;
1914 	}
1915 	*mhz = freq;
1916 	return x;
1917 }
1918 
1919 /*
1920  * to be used with the resync: fast: ... options
1921  */
1922 static inline void set_resync ( struct WD33C93_hostdata *hd, int mask )
1923 {
1924 	int i;
1925 	for (i = 0; i < 8; i++)
1926 		if (mask & (1 << i))
1927 			hd->sync_stat[i] = SS_UNSET;
1928 }
1929 
1930 void
1931 wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs,
1932 	     dma_setup_t setup, dma_stop_t stop, int clock_freq)
1933 {
1934 	struct WD33C93_hostdata *hostdata;
1935 	int i;
1936 	int flags;
1937 	int val;
1938 	char buf[32];
1939 
1940 	if (!done_setup && setup_strings)
1941 		wd33c93_setup(setup_strings);
1942 
1943 	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1944 
1945 	hostdata->regs = regs;
1946 	hostdata->clock_freq = set_clk_freq(clock_freq, &i);
1947 	calc_sx_table(i, hostdata->sx_table);
1948 	hostdata->dma_setup = setup;
1949 	hostdata->dma_stop = stop;
1950 	hostdata->dma_bounce_buffer = NULL;
1951 	hostdata->dma_bounce_len = 0;
1952 	for (i = 0; i < 8; i++) {
1953 		hostdata->busy[i] = 0;
1954 		hostdata->sync_xfer[i] =
1955 			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
1956 					0, hostdata->sx_table);
1957 		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
1958 #ifdef PROC_STATISTICS
1959 		hostdata->cmd_cnt[i] = 0;
1960 		hostdata->disc_allowed_cnt[i] = 0;
1961 		hostdata->disc_done_cnt[i] = 0;
1962 #endif
1963 	}
1964 	hostdata->input_Q = NULL;
1965 	hostdata->selecting = NULL;
1966 	hostdata->connected = NULL;
1967 	hostdata->disconnected_Q = NULL;
1968 	hostdata->state = S_UNCONNECTED;
1969 	hostdata->dma = D_DMA_OFF;
1970 	hostdata->level2 = L2_BASIC;
1971 	hostdata->disconnect = DIS_ADAPTIVE;
1972 	hostdata->args = DEBUG_DEFAULTS;
1973 	hostdata->incoming_ptr = 0;
1974 	hostdata->outgoing_len = 0;
1975 	hostdata->default_sx_per = DEFAULT_SX_PER;
1976 	hostdata->no_dma = 0;	/* default is DMA enabled */
1977 
1978 #ifdef PROC_INTERFACE
1979 	hostdata->proc = PR_VERSION | PR_INFO | PR_STATISTICS |
1980 	    PR_CONNECTED | PR_INPUTQ | PR_DISCQ | PR_STOP;
1981 #ifdef PROC_STATISTICS
1982 	hostdata->dma_cnt = 0;
1983 	hostdata->pio_cnt = 0;
1984 	hostdata->int_cnt = 0;
1985 #endif
1986 #endif
1987 
1988 	if (check_setup_args("clock", &flags, &val, buf)) {
1989 		hostdata->clock_freq = set_clk_freq(val, &val);
1990 		calc_sx_table(val, hostdata->sx_table);
1991 	}
1992 
1993 	if (check_setup_args("nosync", &flags, &val, buf))
1994 		hostdata->no_sync = val;
1995 
1996 	if (check_setup_args("nodma", &flags, &val, buf))
1997 		hostdata->no_dma = (val == -1) ? 1 : val;
1998 
1999 	if (check_setup_args("period", &flags, &val, buf))
2000 		hostdata->default_sx_per =
2001 		    hostdata->sx_table[round_period((unsigned int) val,
2002 		                                    hostdata->sx_table)].period_ns;
2003 
2004 	if (check_setup_args("disconnect", &flags, &val, buf)) {
2005 		if ((val >= DIS_NEVER) && (val <= DIS_ALWAYS))
2006 			hostdata->disconnect = val;
2007 		else
2008 			hostdata->disconnect = DIS_ADAPTIVE;
2009 	}
2010 
2011 	if (check_setup_args("level2", &flags, &val, buf))
2012 		hostdata->level2 = val;
2013 
2014 	if (check_setup_args("debug", &flags, &val, buf))
2015 		hostdata->args = val & DB_MASK;
2016 
2017 	if (check_setup_args("burst", &flags, &val, buf))
2018 		hostdata->dma_mode = val ? CTRL_BURST:CTRL_DMA;
2019 
2020 	if (WD33C93_FS_16_20 == hostdata->clock_freq /* divisor 4 */
2021 		&& check_setup_args("fast", &flags, &val, buf))
2022 		hostdata->fast = !!val;
2023 
2024 	if ((i = check_setup_args("next", &flags, &val, buf))) {
2025 		while (i)
2026 			setup_used[--i] = 1;
2027 	}
2028 #ifdef PROC_INTERFACE
2029 	if (check_setup_args("proc", &flags, &val, buf))
2030 		hostdata->proc = val;
2031 #endif
2032 
2033 	spin_lock_irq(&hostdata->lock);
2034 	reset_wd33c93(instance);
2035 	spin_unlock_irq(&hostdata->lock);
2036 
2037 	printk("wd33c93-%d: chip=%s/%d no_sync=0x%x no_dma=%d",
2038 	       instance->host_no,
2039 	       (hostdata->chip == C_WD33C93) ? "WD33c93" : (hostdata->chip ==
2040 							    C_WD33C93A) ?
2041 	       "WD33c93A" : (hostdata->chip ==
2042 			     C_WD33C93B) ? "WD33c93B" : "unknown",
2043 	       hostdata->microcode, hostdata->no_sync, hostdata->no_dma);
2044 #ifdef DEBUGGING_ON
2045 	printk(" debug_flags=0x%02x\n", hostdata->args);
2046 #else
2047 	printk(" debugging=OFF\n");
2048 #endif
2049 	printk("           setup_args=");
2050 	for (i = 0; i < MAX_SETUP_ARGS; i++)
2051 		printk("%s,", setup_args[i]);
2052 	printk("\n");
2053 	printk("           Version %s - %s, Compiled %s at %s\n",
2054 	       WD33C93_VERSION, WD33C93_DATE, __DATE__, __TIME__);
2055 }
2056 
2057 int
2058 wd33c93_proc_info(struct Scsi_Host *instance, char *buf, char **start, off_t off, int len, int in)
2059 {
2060 
2061 #ifdef PROC_INTERFACE
2062 
2063 	char *bp;
2064 	char tbuf[128];
2065 	struct WD33C93_hostdata *hd;
2066 	struct scsi_cmnd *cmd;
2067 	int x;
2068 	static int stop = 0;
2069 
2070 	hd = (struct WD33C93_hostdata *) instance->hostdata;
2071 
2072 /* If 'in' is TRUE we need to _read_ the proc file. We accept the following
2073  * keywords (same format as command-line, but arguments are not optional):
2074  *    debug
2075  *    disconnect
2076  *    period
2077  *    resync
2078  *    proc
2079  *    nodma
2080  *    level2
2081  *    burst
2082  *    fast
2083  *    nosync
2084  */
2085 
2086 	if (in) {
2087 		buf[len] = '\0';
2088 		for (bp = buf; *bp; ) {
2089 			while (',' == *bp || ' ' == *bp)
2090 				++bp;
2091 		if (!strncmp(bp, "debug:", 6)) {
2092 				hd->args = simple_strtoul(bp+6, &bp, 0) & DB_MASK;
2093 		} else if (!strncmp(bp, "disconnect:", 11)) {
2094 				x = simple_strtoul(bp+11, &bp, 0);
2095 			if (x < DIS_NEVER || x > DIS_ALWAYS)
2096 				x = DIS_ADAPTIVE;
2097 			hd->disconnect = x;
2098 		} else if (!strncmp(bp, "period:", 7)) {
2099 			x = simple_strtoul(bp+7, &bp, 0);
2100 			hd->default_sx_per =
2101 				hd->sx_table[round_period((unsigned int) x,
2102 							  hd->sx_table)].period_ns;
2103 		} else if (!strncmp(bp, "resync:", 7)) {
2104 				set_resync(hd, (int)simple_strtoul(bp+7, &bp, 0));
2105 		} else if (!strncmp(bp, "proc:", 5)) {
2106 				hd->proc = simple_strtoul(bp+5, &bp, 0);
2107 		} else if (!strncmp(bp, "nodma:", 6)) {
2108 				hd->no_dma = simple_strtoul(bp+6, &bp, 0);
2109 		} else if (!strncmp(bp, "level2:", 7)) {
2110 				hd->level2 = simple_strtoul(bp+7, &bp, 0);
2111 			} else if (!strncmp(bp, "burst:", 6)) {
2112 				hd->dma_mode =
2113 					simple_strtol(bp+6, &bp, 0) ? CTRL_BURST:CTRL_DMA;
2114 			} else if (!strncmp(bp, "fast:", 5)) {
2115 				x = !!simple_strtol(bp+5, &bp, 0);
2116 				if (x != hd->fast)
2117 					set_resync(hd, 0xff);
2118 				hd->fast = x;
2119 			} else if (!strncmp(bp, "nosync:", 7)) {
2120 				x = simple_strtoul(bp+7, &bp, 0);
2121 				set_resync(hd, x ^ hd->no_sync);
2122 				hd->no_sync = x;
2123 			} else {
2124 				break; /* unknown keyword,syntax-error,... */
2125 			}
2126 		}
2127 		return len;
2128 	}
2129 
2130 	spin_lock_irq(&hd->lock);
2131 	bp = buf;
2132 	*bp = '\0';
2133 	if (hd->proc & PR_VERSION) {
2134 		sprintf(tbuf, "\nVersion %s - %s. Compiled %s %s",
2135 			WD33C93_VERSION, WD33C93_DATE, __DATE__, __TIME__);
2136 		strcat(bp, tbuf);
2137 	}
2138 	if (hd->proc & PR_INFO) {
2139 		sprintf(tbuf, "\nclock_freq=%02x no_sync=%02x no_dma=%d"
2140 			" dma_mode=%02x fast=%d",
2141 			hd->clock_freq, hd->no_sync, hd->no_dma, hd->dma_mode, hd->fast);
2142 		strcat(bp, tbuf);
2143 		strcat(bp, "\nsync_xfer[] =       ");
2144 		for (x = 0; x < 7; x++) {
2145 			sprintf(tbuf, "\t%02x", hd->sync_xfer[x]);
2146 			strcat(bp, tbuf);
2147 		}
2148 		strcat(bp, "\nsync_stat[] =       ");
2149 		for (x = 0; x < 7; x++) {
2150 			sprintf(tbuf, "\t%02x", hd->sync_stat[x]);
2151 			strcat(bp, tbuf);
2152 		}
2153 	}
2154 #ifdef PROC_STATISTICS
2155 	if (hd->proc & PR_STATISTICS) {
2156 		strcat(bp, "\ncommands issued:    ");
2157 		for (x = 0; x < 7; x++) {
2158 			sprintf(tbuf, "\t%ld", hd->cmd_cnt[x]);
2159 			strcat(bp, tbuf);
2160 		}
2161 		strcat(bp, "\ndisconnects allowed:");
2162 		for (x = 0; x < 7; x++) {
2163 			sprintf(tbuf, "\t%ld", hd->disc_allowed_cnt[x]);
2164 			strcat(bp, tbuf);
2165 		}
2166 		strcat(bp, "\ndisconnects done:   ");
2167 		for (x = 0; x < 7; x++) {
2168 			sprintf(tbuf, "\t%ld", hd->disc_done_cnt[x]);
2169 			strcat(bp, tbuf);
2170 		}
2171 		sprintf(tbuf,
2172 			"\ninterrupts: %ld, DATA_PHASE ints: %ld DMA, %ld PIO",
2173 			hd->int_cnt, hd->dma_cnt, hd->pio_cnt);
2174 		strcat(bp, tbuf);
2175 	}
2176 #endif
2177 	if (hd->proc & PR_CONNECTED) {
2178 		strcat(bp, "\nconnected:     ");
2179 		if (hd->connected) {
2180 			cmd = (struct scsi_cmnd *) hd->connected;
2181 			sprintf(tbuf, " %ld-%d:%d(%02x)",
2182 				cmd->serial_number, cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2183 			strcat(bp, tbuf);
2184 		}
2185 	}
2186 	if (hd->proc & PR_INPUTQ) {
2187 		strcat(bp, "\ninput_Q:       ");
2188 		cmd = (struct scsi_cmnd *) hd->input_Q;
2189 		while (cmd) {
2190 			sprintf(tbuf, " %ld-%d:%d(%02x)",
2191 				cmd->serial_number, cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2192 			strcat(bp, tbuf);
2193 			cmd = (struct scsi_cmnd *) cmd->host_scribble;
2194 		}
2195 	}
2196 	if (hd->proc & PR_DISCQ) {
2197 		strcat(bp, "\ndisconnected_Q:");
2198 		cmd = (struct scsi_cmnd *) hd->disconnected_Q;
2199 		while (cmd) {
2200 			sprintf(tbuf, " %ld-%d:%d(%02x)",
2201 				cmd->serial_number, cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2202 			strcat(bp, tbuf);
2203 			cmd = (struct scsi_cmnd *) cmd->host_scribble;
2204 		}
2205 	}
2206 	strcat(bp, "\n");
2207 	spin_unlock_irq(&hd->lock);
2208 	*start = buf;
2209 	if (stop) {
2210 		stop = 0;
2211 		return 0;
2212 	}
2213 	if (off > 0x40000)	/* ALWAYS stop after 256k bytes have been read */
2214 		stop = 1;
2215 	if (hd->proc & PR_STOP)	/* stop every other time */
2216 		stop = 1;
2217 	return strlen(bp);
2218 
2219 #else				/* PROC_INTERFACE */
2220 
2221 	return 0;
2222 
2223 #endif				/* PROC_INTERFACE */
2224 
2225 }
2226 
2227 void
2228 wd33c93_release(void)
2229 {
2230 }
2231 
2232 EXPORT_SYMBOL(wd33c93_host_reset);
2233 EXPORT_SYMBOL(wd33c93_init);
2234 EXPORT_SYMBOL(wd33c93_release);
2235 EXPORT_SYMBOL(wd33c93_abort);
2236 EXPORT_SYMBOL(wd33c93_queuecommand);
2237 EXPORT_SYMBOL(wd33c93_intr);
2238 EXPORT_SYMBOL(wd33c93_proc_info);
2239