xref: /openbmc/linux/drivers/scsi/wd33c93.c (revision b7b3c35e)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 1996 John Shifflett, GeoLog Consulting
4  *    john@geolog.com
5  *    jshiffle@netcom.com
6  */
7 
8 /*
9  * Drew Eckhardt's excellent 'Generic NCR5380' sources from Linux-PC
10  * provided much of the inspiration and some of the code for this
11  * driver. Everything I know about Amiga DMA was gleaned from careful
12  * reading of Hamish Mcdonald's original wd33c93 driver; in fact, I
13  * borrowed shamelessly from all over that source. Thanks Hamish!
14  *
15  * _This_ driver is (I feel) an improvement over the old one in
16  * several respects:
17  *
18  *    -  Target Disconnection/Reconnection  is now supported. Any
19  *          system with more than one device active on the SCSI bus
20  *          will benefit from this. The driver defaults to what I
21  *          call 'adaptive disconnect' - meaning that each command
22  *          is evaluated individually as to whether or not it should
23  *          be run with the option to disconnect/reselect (if the
24  *          device chooses), or as a "SCSI-bus-hog".
25  *
26  *    -  Synchronous data transfers are now supported. Because of
27  *          a few devices that choke after telling the driver that
28  *          they can do sync transfers, we don't automatically use
29  *          this faster protocol - it can be enabled via the command-
30  *          line on a device-by-device basis.
31  *
32  *    -  Runtime operating parameters can now be specified through
33  *       the 'amiboot' or the 'insmod' command line. For amiboot do:
34  *          "amiboot [usual stuff] wd33c93=blah,blah,blah"
35  *       The defaults should be good for most people. See the comment
36  *       for 'setup_strings' below for more details.
37  *
38  *    -  The old driver relied exclusively on what the Western Digital
39  *          docs call "Combination Level 2 Commands", which are a great
40  *          idea in that the CPU is relieved of a lot of interrupt
41  *          overhead. However, by accepting a certain (user-settable)
42  *          amount of additional interrupts, this driver achieves
43  *          better control over the SCSI bus, and data transfers are
44  *          almost as fast while being much easier to define, track,
45  *          and debug.
46  *
47  *
48  * TODO:
49  *       more speed. linked commands.
50  *
51  *
52  * People with bug reports, wish-lists, complaints, comments,
53  * or improvements are asked to pah-leeez email me (John Shifflett)
54  * at john@geolog.com or jshiffle@netcom.com! I'm anxious to get
55  * this thing into as good a shape as possible, and I'm positive
56  * there are lots of lurking bugs and "Stupid Places".
57  *
58  * Updates:
59  *
60  * Added support for pre -A chips, which don't have advanced features
61  * and will generate CSR_RESEL rather than CSR_RESEL_AM.
62  *	Richard Hirst <richard@sleepie.demon.co.uk>  August 2000
63  *
64  * Added support for Burst Mode DMA and Fast SCSI. Enabled the use of
65  * default_sx_per for asynchronous data transfers. Added adjustment
66  * of transfer periods in sx_table to the actual input-clock.
67  *  peter fuerst <post@pfrst.de>  February 2007
68  */
69 
70 #include <linux/module.h>
71 
72 #include <linux/string.h>
73 #include <linux/delay.h>
74 #include <linux/init.h>
75 #include <linux/interrupt.h>
76 #include <linux/blkdev.h>
77 
78 #include <scsi/scsi.h>
79 #include <scsi/scsi_cmnd.h>
80 #include <scsi/scsi_device.h>
81 #include <scsi/scsi_host.h>
82 
83 #include <asm/irq.h>
84 
85 #include "wd33c93.h"
86 
87 #define optimum_sx_per(hostdata) (hostdata)->sx_table[1].period_ns
88 
89 
90 #define WD33C93_VERSION    "1.26++"
91 #define WD33C93_DATE       "10/Feb/2007"
92 
93 MODULE_AUTHOR("John Shifflett");
94 MODULE_DESCRIPTION("Generic WD33C93 SCSI driver");
95 MODULE_LICENSE("GPL");
96 
97 /*
98  * 'setup_strings' is a single string used to pass operating parameters and
99  * settings from the kernel/module command-line to the driver. 'setup_args[]'
100  * is an array of strings that define the compile-time default values for
101  * these settings. If Linux boots with an amiboot or insmod command-line,
102  * those settings are combined with 'setup_args[]'. Note that amiboot
103  * command-lines are prefixed with "wd33c93=" while insmod uses a
104  * "setup_strings=" prefix. The driver recognizes the following keywords
105  * (lower case required) and arguments:
106  *
107  * -  nosync:bitmask -bitmask is a byte where the 1st 7 bits correspond with
108  *                    the 7 possible SCSI devices. Set a bit to negotiate for
109  *                    asynchronous transfers on that device. To maintain
110  *                    backwards compatibility, a command-line such as
111  *                    "wd33c93=255" will be automatically translated to
112  *                    "wd33c93=nosync:0xff".
113  * -  nodma:x        -x = 1 to disable DMA, x = 0 to enable it. Argument is
114  *                    optional - if not present, same as "nodma:1".
115  * -  period:ns      -ns is the minimum # of nanoseconds in a SCSI data transfer
116  *                    period. Default is 500; acceptable values are 250 - 1000.
117  * -  disconnect:x   -x = 0 to never allow disconnects, 2 to always allow them.
118  *                    x = 1 does 'adaptive' disconnects, which is the default
119  *                    and generally the best choice.
120  * -  debug:x        -If 'DEBUGGING_ON' is defined, x is a bit mask that causes
121  *                    various types of debug output to printed - see the DB_xxx
122  *                    defines in wd33c93.h
123  * -  clock:x        -x = clock input in MHz for WD33c93 chip. Normal values
124  *                    would be from 8 through 20. Default is 8.
125  * -  burst:x        -x = 1 to use Burst Mode (or Demand-Mode) DMA, x = 0 to use
126  *                    Single Byte DMA, which is the default. Argument is
127  *                    optional - if not present, same as "burst:1".
128  * -  fast:x         -x = 1 to enable Fast SCSI, which is only effective with
129  *                    input-clock divisor 4 (WD33C93_FS_16_20), x = 0 to disable
130  *                    it, which is the default.  Argument is optional - if not
131  *                    present, same as "fast:1".
132  * -  next           -No argument. Used to separate blocks of keywords when
133  *                    there's more than one host adapter in the system.
134  *
135  * Syntax Notes:
136  * -  Numeric arguments can be decimal or the '0x' form of hex notation. There
137  *    _must_ be a colon between a keyword and its numeric argument, with no
138  *    spaces.
139  * -  Keywords are separated by commas, no spaces, in the standard kernel
140  *    command-line manner.
141  * -  A keyword in the 'nth' comma-separated command-line member will overwrite
142  *    the 'nth' element of setup_args[]. A blank command-line member (in
143  *    other words, a comma with no preceding keyword) will _not_ overwrite
144  *    the corresponding setup_args[] element.
145  * -  If a keyword is used more than once, the first one applies to the first
146  *    SCSI host found, the second to the second card, etc, unless the 'next'
147  *    keyword is used to change the order.
148  *
149  * Some amiboot examples (for insmod, use 'setup_strings' instead of 'wd33c93'):
150  * -  wd33c93=nosync:255
151  * -  wd33c93=nodma
152  * -  wd33c93=nodma:1
153  * -  wd33c93=disconnect:2,nosync:0x08,period:250
154  * -  wd33c93=debug:0x1c
155  */
156 
157 /* Normally, no defaults are specified */
158 static char *setup_args[] = { "", "", "", "", "", "", "", "", "", "" };
159 
160 static char *setup_strings;
161 module_param(setup_strings, charp, 0);
162 
163 static void wd33c93_execute(struct Scsi_Host *instance);
164 
165 #ifdef CONFIG_WD33C93_PIO
166 static inline uchar
167 read_wd33c93(const wd33c93_regs regs, uchar reg_num)
168 {
169 	uchar data;
170 
171 	outb(reg_num, regs.SASR);
172 	data = inb(regs.SCMD);
173 	return data;
174 }
175 
176 static inline unsigned long
177 read_wd33c93_count(const wd33c93_regs regs)
178 {
179 	unsigned long value;
180 
181 	outb(WD_TRANSFER_COUNT_MSB, regs.SASR);
182 	value = inb(regs.SCMD) << 16;
183 	value |= inb(regs.SCMD) << 8;
184 	value |= inb(regs.SCMD);
185 	return value;
186 }
187 
188 static inline uchar
189 read_aux_stat(const wd33c93_regs regs)
190 {
191 	return inb(regs.SASR);
192 }
193 
194 static inline void
195 write_wd33c93(const wd33c93_regs regs, uchar reg_num, uchar value)
196 {
197       outb(reg_num, regs.SASR);
198       outb(value, regs.SCMD);
199 }
200 
201 static inline void
202 write_wd33c93_count(const wd33c93_regs regs, unsigned long value)
203 {
204 	outb(WD_TRANSFER_COUNT_MSB, regs.SASR);
205 	outb((value >> 16) & 0xff, regs.SCMD);
206 	outb((value >> 8) & 0xff, regs.SCMD);
207 	outb( value & 0xff, regs.SCMD);
208 }
209 
210 #define write_wd33c93_cmd(regs, cmd) \
211 	write_wd33c93((regs), WD_COMMAND, (cmd))
212 
213 static inline void
214 write_wd33c93_cdb(const wd33c93_regs regs, uint len, uchar cmnd[])
215 {
216 	int i;
217 
218 	outb(WD_CDB_1, regs.SASR);
219 	for (i=0; i<len; i++)
220 		outb(cmnd[i], regs.SCMD);
221 }
222 
223 #else /* CONFIG_WD33C93_PIO */
224 static inline uchar
225 read_wd33c93(const wd33c93_regs regs, uchar reg_num)
226 {
227 	*regs.SASR = reg_num;
228 	mb();
229 	return (*regs.SCMD);
230 }
231 
232 static unsigned long
233 read_wd33c93_count(const wd33c93_regs regs)
234 {
235 	unsigned long value;
236 
237 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
238 	mb();
239 	value = *regs.SCMD << 16;
240 	value |= *regs.SCMD << 8;
241 	value |= *regs.SCMD;
242 	mb();
243 	return value;
244 }
245 
246 static inline uchar
247 read_aux_stat(const wd33c93_regs regs)
248 {
249 	return *regs.SASR;
250 }
251 
252 static inline void
253 write_wd33c93(const wd33c93_regs regs, uchar reg_num, uchar value)
254 {
255 	*regs.SASR = reg_num;
256 	mb();
257 	*regs.SCMD = value;
258 	mb();
259 }
260 
261 static void
262 write_wd33c93_count(const wd33c93_regs regs, unsigned long value)
263 {
264 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
265 	mb();
266 	*regs.SCMD = value >> 16;
267 	*regs.SCMD = value >> 8;
268 	*regs.SCMD = value;
269 	mb();
270 }
271 
272 static inline void
273 write_wd33c93_cmd(const wd33c93_regs regs, uchar cmd)
274 {
275 	*regs.SASR = WD_COMMAND;
276 	mb();
277 	*regs.SCMD = cmd;
278 	mb();
279 }
280 
281 static inline void
282 write_wd33c93_cdb(const wd33c93_regs regs, uint len, uchar cmnd[])
283 {
284 	int i;
285 
286 	*regs.SASR = WD_CDB_1;
287 	for (i = 0; i < len; i++)
288 		*regs.SCMD = cmnd[i];
289 }
290 #endif /* CONFIG_WD33C93_PIO */
291 
292 static inline uchar
293 read_1_byte(const wd33c93_regs regs)
294 {
295 	uchar asr;
296 	uchar x = 0;
297 
298 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
299 	write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO | 0x80);
300 	do {
301 		asr = read_aux_stat(regs);
302 		if (asr & ASR_DBR)
303 			x = read_wd33c93(regs, WD_DATA);
304 	} while (!(asr & ASR_INT));
305 	return x;
306 }
307 
308 static int
309 round_period(unsigned int period, const struct sx_period *sx_table)
310 {
311 	int x;
312 
313 	for (x = 1; sx_table[x].period_ns; x++) {
314 		if ((period <= sx_table[x - 0].period_ns) &&
315 		    (period > sx_table[x - 1].period_ns)) {
316 			return x;
317 		}
318 	}
319 	return 7;
320 }
321 
322 /*
323  * Calculate Synchronous Transfer Register value from SDTR code.
324  */
325 static uchar
326 calc_sync_xfer(unsigned int period, unsigned int offset, unsigned int fast,
327                const struct sx_period *sx_table)
328 {
329 	/* When doing Fast SCSI synchronous data transfers, the corresponding
330 	 * value in 'sx_table' is two times the actually used transfer period.
331 	 */
332 	uchar result;
333 
334 	if (offset && fast) {
335 		fast = STR_FSS;
336 		period *= 2;
337 	} else {
338 		fast = 0;
339 	}
340 	period *= 4;		/* convert SDTR code to ns */
341 	result = sx_table[round_period(period,sx_table)].reg_value;
342 	result |= (offset < OPTIMUM_SX_OFF) ? offset : OPTIMUM_SX_OFF;
343 	result |= fast;
344 	return result;
345 }
346 
347 /*
348  * Calculate SDTR code bytes [3],[4] from period and offset.
349  */
350 static inline void
351 calc_sync_msg(unsigned int period, unsigned int offset, unsigned int fast,
352                 uchar  msg[2])
353 {
354 	/* 'period' is a "normal"-mode value, like the ones in 'sx_table'. The
355 	 * actually used transfer period for Fast SCSI synchronous data
356 	 * transfers is half that value.
357 	 */
358 	period /= 4;
359 	if (offset && fast)
360 		period /= 2;
361 	msg[0] = period;
362 	msg[1] = offset;
363 }
364 
365 static int wd33c93_queuecommand_lck(struct scsi_cmnd *cmd)
366 {
367 	struct WD33C93_hostdata *hostdata;
368 	struct scsi_cmnd *tmp;
369 
370 	hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
371 
372 	DB(DB_QUEUE_COMMAND,
373 	   printk("Q-%d-%02x( ", cmd->device->id, cmd->cmnd[0]))
374 
375 /* Set up a few fields in the scsi_cmnd structure for our own use:
376  *  - host_scribble is the pointer to the next cmd in the input queue
377  *  - result is what you'd expect
378  */
379 	cmd->host_scribble = NULL;
380 	cmd->result = 0;
381 
382 /* We use the Scsi_Pointer structure that's included with each command
383  * as a scratchpad (as it's intended to be used!). The handy thing about
384  * the SCp.xxx fields is that they're always associated with a given
385  * cmd, and are preserved across disconnect-reselect. This means we
386  * can pretty much ignore SAVE_POINTERS and RESTORE_POINTERS messages
387  * if we keep all the critical pointers and counters in SCp:
388  *  - SCp.ptr is the pointer into the RAM buffer
389  *  - SCp.this_residual is the size of that buffer
390  *  - SCp.buffer points to the current scatter-gather buffer
391  *  - SCp.buffers_residual tells us how many S.G. buffers there are
392  *  - SCp.have_data_in is not used
393  *  - SCp.sent_command is not used
394  *  - SCp.phase records this command's SRCID_ER bit setting
395  */
396 
397 	if (scsi_bufflen(cmd)) {
398 		cmd->SCp.buffer = scsi_sglist(cmd);
399 		cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
400 		cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
401 		cmd->SCp.this_residual = cmd->SCp.buffer->length;
402 	} else {
403 		cmd->SCp.buffer = NULL;
404 		cmd->SCp.buffers_residual = 0;
405 		cmd->SCp.ptr = NULL;
406 		cmd->SCp.this_residual = 0;
407 	}
408 
409 /* WD docs state that at the conclusion of a "LEVEL2" command, the
410  * status byte can be retrieved from the LUN register. Apparently,
411  * this is the case only for *uninterrupted* LEVEL2 commands! If
412  * there are any unexpected phases entered, even if they are 100%
413  * legal (different devices may choose to do things differently),
414  * the LEVEL2 command sequence is exited. This often occurs prior
415  * to receiving the status byte, in which case the driver does a
416  * status phase interrupt and gets the status byte on its own.
417  * While such a command can then be "resumed" (ie restarted to
418  * finish up as a LEVEL2 command), the LUN register will NOT be
419  * a valid status byte at the command's conclusion, and we must
420  * use the byte obtained during the earlier interrupt. Here, we
421  * preset SCp.Status to an illegal value (0xff) so that when
422  * this command finally completes, we can tell where the actual
423  * status byte is stored.
424  */
425 
426 	cmd->SCp.Status = ILLEGAL_STATUS_BYTE;
427 
428 	/*
429 	 * Add the cmd to the end of 'input_Q'. Note that REQUEST SENSE
430 	 * commands are added to the head of the queue so that the desired
431 	 * sense data is not lost before REQUEST_SENSE executes.
432 	 */
433 
434 	spin_lock_irq(&hostdata->lock);
435 
436 	if (!(hostdata->input_Q) || (cmd->cmnd[0] == REQUEST_SENSE)) {
437 		cmd->host_scribble = (uchar *) hostdata->input_Q;
438 		hostdata->input_Q = cmd;
439 	} else {		/* find the end of the queue */
440 		for (tmp = (struct scsi_cmnd *) hostdata->input_Q;
441 		     tmp->host_scribble;
442 		     tmp = (struct scsi_cmnd *) tmp->host_scribble) ;
443 		tmp->host_scribble = (uchar *) cmd;
444 	}
445 
446 /* We know that there's at least one command in 'input_Q' now.
447  * Go see if any of them are runnable!
448  */
449 
450 	wd33c93_execute(cmd->device->host);
451 
452 	DB(DB_QUEUE_COMMAND, printk(")Q "))
453 
454 	spin_unlock_irq(&hostdata->lock);
455 	return 0;
456 }
457 
458 DEF_SCSI_QCMD(wd33c93_queuecommand)
459 
460 /*
461  * This routine attempts to start a scsi command. If the host_card is
462  * already connected, we give up immediately. Otherwise, look through
463  * the input_Q, using the first command we find that's intended
464  * for a currently non-busy target/lun.
465  *
466  * wd33c93_execute() is always called with interrupts disabled or from
467  * the wd33c93_intr itself, which means that a wd33c93 interrupt
468  * cannot occur while we are in here.
469  */
470 static void
471 wd33c93_execute(struct Scsi_Host *instance)
472 {
473 	struct WD33C93_hostdata *hostdata =
474 	    (struct WD33C93_hostdata *) instance->hostdata;
475 	const wd33c93_regs regs = hostdata->regs;
476 	struct scsi_cmnd *cmd, *prev;
477 
478 	DB(DB_EXECUTE, printk("EX("))
479 	if (hostdata->selecting || hostdata->connected) {
480 		DB(DB_EXECUTE, printk(")EX-0 "))
481 		return;
482 	}
483 
484 	/*
485 	 * Search through the input_Q for a command destined
486 	 * for an idle target/lun.
487 	 */
488 
489 	cmd = (struct scsi_cmnd *) hostdata->input_Q;
490 	prev = NULL;
491 	while (cmd) {
492 		if (!(hostdata->busy[cmd->device->id] &
493 		      (1 << (cmd->device->lun & 0xff))))
494 			break;
495 		prev = cmd;
496 		cmd = (struct scsi_cmnd *) cmd->host_scribble;
497 	}
498 
499 	/* quit if queue empty or all possible targets are busy */
500 
501 	if (!cmd) {
502 		DB(DB_EXECUTE, printk(")EX-1 "))
503 		return;
504 	}
505 
506 	/*  remove command from queue */
507 
508 	if (prev)
509 		prev->host_scribble = cmd->host_scribble;
510 	else
511 		hostdata->input_Q = (struct scsi_cmnd *) cmd->host_scribble;
512 
513 #ifdef PROC_STATISTICS
514 	hostdata->cmd_cnt[cmd->device->id]++;
515 #endif
516 
517 	/*
518 	 * Start the selection process
519 	 */
520 
521 	if (cmd->sc_data_direction == DMA_TO_DEVICE)
522 		write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
523 	else
524 		write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id | DSTID_DPD);
525 
526 /* Now we need to figure out whether or not this command is a good
527  * candidate for disconnect/reselect. We guess to the best of our
528  * ability, based on a set of hierarchical rules. When several
529  * devices are operating simultaneously, disconnects are usually
530  * an advantage. In a single device system, or if only 1 device
531  * is being accessed, transfers usually go faster if disconnects
532  * are not allowed:
533  *
534  * + Commands should NEVER disconnect if hostdata->disconnect =
535  *   DIS_NEVER (this holds for tape drives also), and ALWAYS
536  *   disconnect if hostdata->disconnect = DIS_ALWAYS.
537  * + Tape drive commands should always be allowed to disconnect.
538  * + Disconnect should be allowed if disconnected_Q isn't empty.
539  * + Commands should NOT disconnect if input_Q is empty.
540  * + Disconnect should be allowed if there are commands in input_Q
541  *   for a different target/lun. In this case, the other commands
542  *   should be made disconnect-able, if not already.
543  *
544  * I know, I know - this code would flunk me out of any
545  * "C Programming 101" class ever offered. But it's easy
546  * to change around and experiment with for now.
547  */
548 
549 	cmd->SCp.phase = 0;	/* assume no disconnect */
550 	if (hostdata->disconnect == DIS_NEVER)
551 		goto no;
552 	if (hostdata->disconnect == DIS_ALWAYS)
553 		goto yes;
554 	if (cmd->device->type == 1)	/* tape drive? */
555 		goto yes;
556 	if (hostdata->disconnected_Q)	/* other commands disconnected? */
557 		goto yes;
558 	if (!(hostdata->input_Q))	/* input_Q empty? */
559 		goto no;
560 	for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
561 	     prev = (struct scsi_cmnd *) prev->host_scribble) {
562 		if ((prev->device->id != cmd->device->id) ||
563 		    (prev->device->lun != cmd->device->lun)) {
564 			for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
565 			     prev = (struct scsi_cmnd *) prev->host_scribble)
566 				prev->SCp.phase = 1;
567 			goto yes;
568 		}
569 	}
570 
571 	goto no;
572 
573  yes:
574 	cmd->SCp.phase = 1;
575 
576 #ifdef PROC_STATISTICS
577 	hostdata->disc_allowed_cnt[cmd->device->id]++;
578 #endif
579 
580  no:
581 
582 	write_wd33c93(regs, WD_SOURCE_ID, ((cmd->SCp.phase) ? SRCID_ER : 0));
583 
584 	write_wd33c93(regs, WD_TARGET_LUN, (u8)cmd->device->lun);
585 	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
586 		      hostdata->sync_xfer[cmd->device->id]);
587 	hostdata->busy[cmd->device->id] |= (1 << (cmd->device->lun & 0xFF));
588 
589 	if ((hostdata->level2 == L2_NONE) ||
590 	    (hostdata->sync_stat[cmd->device->id] == SS_UNSET)) {
591 
592 		/*
593 		 * Do a 'Select-With-ATN' command. This will end with
594 		 * one of the following interrupts:
595 		 *    CSR_RESEL_AM:  failure - can try again later.
596 		 *    CSR_TIMEOUT:   failure - give up.
597 		 *    CSR_SELECT:    success - proceed.
598 		 */
599 
600 		hostdata->selecting = cmd;
601 
602 /* Every target has its own synchronous transfer setting, kept in the
603  * sync_xfer array, and a corresponding status byte in sync_stat[].
604  * Each target's sync_stat[] entry is initialized to SX_UNSET, and its
605  * sync_xfer[] entry is initialized to the default/safe value. SS_UNSET
606  * means that the parameters are undetermined as yet, and that we
607  * need to send an SDTR message to this device after selection is
608  * complete: We set SS_FIRST to tell the interrupt routine to do so.
609  * If we've been asked not to try synchronous transfers on this
610  * target (and _all_ luns within it), we'll still send the SDTR message
611  * later, but at that time we'll negotiate for async by specifying a
612  * sync fifo depth of 0.
613  */
614 		if (hostdata->sync_stat[cmd->device->id] == SS_UNSET)
615 			hostdata->sync_stat[cmd->device->id] = SS_FIRST;
616 		hostdata->state = S_SELECTING;
617 		write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
618 		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN);
619 	} else {
620 
621 		/*
622 		 * Do a 'Select-With-ATN-Xfer' command. This will end with
623 		 * one of the following interrupts:
624 		 *    CSR_RESEL_AM:  failure - can try again later.
625 		 *    CSR_TIMEOUT:   failure - give up.
626 		 *    anything else: success - proceed.
627 		 */
628 
629 		hostdata->connected = cmd;
630 		write_wd33c93(regs, WD_COMMAND_PHASE, 0);
631 
632 		/* copy command_descriptor_block into WD chip
633 		 * (take advantage of auto-incrementing)
634 		 */
635 
636 		write_wd33c93_cdb(regs, cmd->cmd_len, cmd->cmnd);
637 
638 		/* The wd33c93 only knows about Group 0, 1, and 5 commands when
639 		 * it's doing a 'select-and-transfer'. To be safe, we write the
640 		 * size of the CDB into the OWN_ID register for every case. This
641 		 * way there won't be problems with vendor-unique, audio, etc.
642 		 */
643 
644 		write_wd33c93(regs, WD_OWN_ID, cmd->cmd_len);
645 
646 		/* When doing a non-disconnect command with DMA, we can save
647 		 * ourselves a DATA phase interrupt later by setting everything
648 		 * up ahead of time.
649 		 */
650 
651 		if ((cmd->SCp.phase == 0) && (hostdata->no_dma == 0)) {
652 			if (hostdata->dma_setup(cmd,
653 			    (cmd->sc_data_direction == DMA_TO_DEVICE) ?
654 			     DATA_OUT_DIR : DATA_IN_DIR))
655 				write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
656 			else {
657 				write_wd33c93_count(regs,
658 						    cmd->SCp.this_residual);
659 				write_wd33c93(regs, WD_CONTROL,
660 					      CTRL_IDI | CTRL_EDI | hostdata->dma_mode);
661 				hostdata->dma = D_DMA_RUNNING;
662 			}
663 		} else
664 			write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
665 
666 		hostdata->state = S_RUNNING_LEVEL2;
667 		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
668 	}
669 
670 	/*
671 	 * Since the SCSI bus can handle only 1 connection at a time,
672 	 * we get out of here now. If the selection fails, or when
673 	 * the command disconnects, we'll come back to this routine
674 	 * to search the input_Q again...
675 	 */
676 
677 	DB(DB_EXECUTE,
678 	   printk("%s)EX-2 ", (cmd->SCp.phase) ? "d:" : ""))
679 }
680 
681 static void
682 transfer_pio(const wd33c93_regs regs, uchar * buf, int cnt,
683 	     int data_in_dir, struct WD33C93_hostdata *hostdata)
684 {
685 	uchar asr;
686 
687 	DB(DB_TRANSFER,
688 	   printk("(%p,%d,%s:", buf, cnt, data_in_dir ? "in" : "out"))
689 
690 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
691 	write_wd33c93_count(regs, cnt);
692 	write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
693 	if (data_in_dir) {
694 		do {
695 			asr = read_aux_stat(regs);
696 			if (asr & ASR_DBR)
697 				*buf++ = read_wd33c93(regs, WD_DATA);
698 		} while (!(asr & ASR_INT));
699 	} else {
700 		do {
701 			asr = read_aux_stat(regs);
702 			if (asr & ASR_DBR)
703 				write_wd33c93(regs, WD_DATA, *buf++);
704 		} while (!(asr & ASR_INT));
705 	}
706 
707 	/* Note: we are returning with the interrupt UN-cleared.
708 	 * Since (presumably) an entire I/O operation has
709 	 * completed, the bus phase is probably different, and
710 	 * the interrupt routine will discover this when it
711 	 * responds to the uncleared int.
712 	 */
713 
714 }
715 
716 static void
717 transfer_bytes(const wd33c93_regs regs, struct scsi_cmnd *cmd,
718 		int data_in_dir)
719 {
720 	struct WD33C93_hostdata *hostdata;
721 	unsigned long length;
722 
723 	hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
724 
725 /* Normally, you'd expect 'this_residual' to be non-zero here.
726  * In a series of scatter-gather transfers, however, this
727  * routine will usually be called with 'this_residual' equal
728  * to 0 and 'buffers_residual' non-zero. This means that a
729  * previous transfer completed, clearing 'this_residual', and
730  * now we need to setup the next scatter-gather buffer as the
731  * source or destination for THIS transfer.
732  */
733 	if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
734 		cmd->SCp.buffer = sg_next(cmd->SCp.buffer);
735 		--cmd->SCp.buffers_residual;
736 		cmd->SCp.this_residual = cmd->SCp.buffer->length;
737 		cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
738 	}
739 	if (!cmd->SCp.this_residual) /* avoid bogus setups */
740 		return;
741 
742 	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
743 		      hostdata->sync_xfer[cmd->device->id]);
744 
745 /* 'hostdata->no_dma' is TRUE if we don't even want to try DMA.
746  * Update 'this_residual' and 'ptr' after 'transfer_pio()' returns.
747  */
748 
749 	if (hostdata->no_dma || hostdata->dma_setup(cmd, data_in_dir)) {
750 #ifdef PROC_STATISTICS
751 		hostdata->pio_cnt++;
752 #endif
753 		transfer_pio(regs, (uchar *) cmd->SCp.ptr,
754 			     cmd->SCp.this_residual, data_in_dir, hostdata);
755 		length = cmd->SCp.this_residual;
756 		cmd->SCp.this_residual = read_wd33c93_count(regs);
757 		cmd->SCp.ptr += (length - cmd->SCp.this_residual);
758 	}
759 
760 /* We are able to do DMA (in fact, the Amiga hardware is
761  * already going!), so start up the wd33c93 in DMA mode.
762  * We set 'hostdata->dma' = D_DMA_RUNNING so that when the
763  * transfer completes and causes an interrupt, we're
764  * reminded to tell the Amiga to shut down its end. We'll
765  * postpone the updating of 'this_residual' and 'ptr'
766  * until then.
767  */
768 
769 	else {
770 #ifdef PROC_STATISTICS
771 		hostdata->dma_cnt++;
772 #endif
773 		write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | hostdata->dma_mode);
774 		write_wd33c93_count(regs, cmd->SCp.this_residual);
775 
776 		if ((hostdata->level2 >= L2_DATA) ||
777 		    (hostdata->level2 == L2_BASIC && cmd->SCp.phase == 0)) {
778 			write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
779 			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
780 			hostdata->state = S_RUNNING_LEVEL2;
781 		} else
782 			write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
783 
784 		hostdata->dma = D_DMA_RUNNING;
785 	}
786 }
787 
788 void
789 wd33c93_intr(struct Scsi_Host *instance)
790 {
791 	struct WD33C93_hostdata *hostdata =
792 	    (struct WD33C93_hostdata *) instance->hostdata;
793 	const wd33c93_regs regs = hostdata->regs;
794 	struct scsi_cmnd *patch, *cmd;
795 	uchar asr, sr, phs, id, lun, *ucp, msg;
796 	unsigned long length, flags;
797 
798 	asr = read_aux_stat(regs);
799 	if (!(asr & ASR_INT) || (asr & ASR_BSY))
800 		return;
801 
802 	spin_lock_irqsave(&hostdata->lock, flags);
803 
804 #ifdef PROC_STATISTICS
805 	hostdata->int_cnt++;
806 #endif
807 
808 	cmd = (struct scsi_cmnd *) hostdata->connected;	/* assume we're connected */
809 	sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear the interrupt */
810 	phs = read_wd33c93(regs, WD_COMMAND_PHASE);
811 
812 	DB(DB_INTR, printk("{%02x:%02x-", asr, sr))
813 
814 /* After starting a DMA transfer, the next interrupt
815  * is guaranteed to be in response to completion of
816  * the transfer. Since the Amiga DMA hardware runs in
817  * in an open-ended fashion, it needs to be told when
818  * to stop; do that here if D_DMA_RUNNING is true.
819  * Also, we have to update 'this_residual' and 'ptr'
820  * based on the contents of the TRANSFER_COUNT register,
821  * in case the device decided to do an intermediate
822  * disconnect (a device may do this if it has to do a
823  * seek, or just to be nice and let other devices have
824  * some bus time during long transfers). After doing
825  * whatever is needed, we go on and service the WD3393
826  * interrupt normally.
827  */
828 	    if (hostdata->dma == D_DMA_RUNNING) {
829 		DB(DB_TRANSFER,
830 		   printk("[%p/%d:", cmd->SCp.ptr, cmd->SCp.this_residual))
831 		    hostdata->dma_stop(cmd->device->host, cmd, 1);
832 		hostdata->dma = D_DMA_OFF;
833 		length = cmd->SCp.this_residual;
834 		cmd->SCp.this_residual = read_wd33c93_count(regs);
835 		cmd->SCp.ptr += (length - cmd->SCp.this_residual);
836 		DB(DB_TRANSFER,
837 		   printk("%p/%d]", cmd->SCp.ptr, cmd->SCp.this_residual))
838 	}
839 
840 /* Respond to the specific WD3393 interrupt - there are quite a few! */
841 	switch (sr) {
842 	case CSR_TIMEOUT:
843 		DB(DB_INTR, printk("TIMEOUT"))
844 
845 		    if (hostdata->state == S_RUNNING_LEVEL2)
846 			hostdata->connected = NULL;
847 		else {
848 			cmd = (struct scsi_cmnd *) hostdata->selecting;	/* get a valid cmd */
849 			hostdata->selecting = NULL;
850 		}
851 
852 		cmd->result = DID_NO_CONNECT << 16;
853 		hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
854 		hostdata->state = S_UNCONNECTED;
855 		scsi_done(cmd);
856 
857 		/* From esp.c:
858 		 * There is a window of time within the scsi_done() path
859 		 * of execution where interrupts are turned back on full
860 		 * blast and left that way.  During that time we could
861 		 * reconnect to a disconnected command, then we'd bomb
862 		 * out below.  We could also end up executing two commands
863 		 * at _once_.  ...just so you know why the restore_flags()
864 		 * is here...
865 		 */
866 
867 		spin_unlock_irqrestore(&hostdata->lock, flags);
868 
869 /* We are not connected to a target - check to see if there
870  * are commands waiting to be executed.
871  */
872 
873 		wd33c93_execute(instance);
874 		break;
875 
876 /* Note: this interrupt should not occur in a LEVEL2 command */
877 
878 	case CSR_SELECT:
879 		DB(DB_INTR, printk("SELECT"))
880 		    hostdata->connected = cmd =
881 		    (struct scsi_cmnd *) hostdata->selecting;
882 		hostdata->selecting = NULL;
883 
884 		/* construct an IDENTIFY message with correct disconnect bit */
885 
886 		hostdata->outgoing_msg[0] = IDENTIFY(0, cmd->device->lun);
887 		if (cmd->SCp.phase)
888 			hostdata->outgoing_msg[0] |= 0x40;
889 
890 		if (hostdata->sync_stat[cmd->device->id] == SS_FIRST) {
891 
892 			hostdata->sync_stat[cmd->device->id] = SS_WAITING;
893 
894 /* Tack on a 2nd message to ask about synchronous transfers. If we've
895  * been asked to do only asynchronous transfers on this device, we
896  * request a fifo depth of 0, which is equivalent to async - should
897  * solve the problems some people have had with GVP's Guru ROM.
898  */
899 
900 			hostdata->outgoing_msg[1] = EXTENDED_MESSAGE;
901 			hostdata->outgoing_msg[2] = 3;
902 			hostdata->outgoing_msg[3] = EXTENDED_SDTR;
903 			if (hostdata->no_sync & (1 << cmd->device->id)) {
904 				calc_sync_msg(hostdata->default_sx_per, 0,
905 						0, hostdata->outgoing_msg + 4);
906 			} else {
907 				calc_sync_msg(optimum_sx_per(hostdata),
908 						OPTIMUM_SX_OFF,
909 						hostdata->fast,
910 						hostdata->outgoing_msg + 4);
911 			}
912 			hostdata->outgoing_len = 6;
913 #ifdef SYNC_DEBUG
914 			ucp = hostdata->outgoing_msg + 1;
915 			printk(" sending SDTR %02x03%02x%02x%02x ",
916 				ucp[0], ucp[2], ucp[3], ucp[4]);
917 #endif
918 		} else
919 			hostdata->outgoing_len = 1;
920 
921 		hostdata->state = S_CONNECTED;
922 		spin_unlock_irqrestore(&hostdata->lock, flags);
923 		break;
924 
925 	case CSR_XFER_DONE | PHS_DATA_IN:
926 	case CSR_UNEXP | PHS_DATA_IN:
927 	case CSR_SRV_REQ | PHS_DATA_IN:
928 		DB(DB_INTR,
929 		   printk("IN-%d.%d", cmd->SCp.this_residual,
930 			  cmd->SCp.buffers_residual))
931 		    transfer_bytes(regs, cmd, DATA_IN_DIR);
932 		if (hostdata->state != S_RUNNING_LEVEL2)
933 			hostdata->state = S_CONNECTED;
934 		spin_unlock_irqrestore(&hostdata->lock, flags);
935 		break;
936 
937 	case CSR_XFER_DONE | PHS_DATA_OUT:
938 	case CSR_UNEXP | PHS_DATA_OUT:
939 	case CSR_SRV_REQ | PHS_DATA_OUT:
940 		DB(DB_INTR,
941 		   printk("OUT-%d.%d", cmd->SCp.this_residual,
942 			  cmd->SCp.buffers_residual))
943 		    transfer_bytes(regs, cmd, DATA_OUT_DIR);
944 		if (hostdata->state != S_RUNNING_LEVEL2)
945 			hostdata->state = S_CONNECTED;
946 		spin_unlock_irqrestore(&hostdata->lock, flags);
947 		break;
948 
949 /* Note: this interrupt should not occur in a LEVEL2 command */
950 
951 	case CSR_XFER_DONE | PHS_COMMAND:
952 	case CSR_UNEXP | PHS_COMMAND:
953 	case CSR_SRV_REQ | PHS_COMMAND:
954 		DB(DB_INTR, printk("CMND-%02x", cmd->cmnd[0]))
955 		    transfer_pio(regs, cmd->cmnd, cmd->cmd_len, DATA_OUT_DIR,
956 				 hostdata);
957 		hostdata->state = S_CONNECTED;
958 		spin_unlock_irqrestore(&hostdata->lock, flags);
959 		break;
960 
961 	case CSR_XFER_DONE | PHS_STATUS:
962 	case CSR_UNEXP | PHS_STATUS:
963 	case CSR_SRV_REQ | PHS_STATUS:
964 		DB(DB_INTR, printk("STATUS="))
965 		cmd->SCp.Status = read_1_byte(regs);
966 		DB(DB_INTR, printk("%02x", cmd->SCp.Status))
967 		    if (hostdata->level2 >= L2_BASIC) {
968 			sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear interrupt */
969 			udelay(7);
970 			hostdata->state = S_RUNNING_LEVEL2;
971 			write_wd33c93(regs, WD_COMMAND_PHASE, 0x50);
972 			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
973 		} else {
974 			hostdata->state = S_CONNECTED;
975 		}
976 		spin_unlock_irqrestore(&hostdata->lock, flags);
977 		break;
978 
979 	case CSR_XFER_DONE | PHS_MESS_IN:
980 	case CSR_UNEXP | PHS_MESS_IN:
981 	case CSR_SRV_REQ | PHS_MESS_IN:
982 		DB(DB_INTR, printk("MSG_IN="))
983 
984 		msg = read_1_byte(regs);
985 		sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear interrupt */
986 		udelay(7);
987 
988 		hostdata->incoming_msg[hostdata->incoming_ptr] = msg;
989 		if (hostdata->incoming_msg[0] == EXTENDED_MESSAGE)
990 			msg = EXTENDED_MESSAGE;
991 		else
992 			hostdata->incoming_ptr = 0;
993 
994 		cmd->SCp.Message = msg;
995 		switch (msg) {
996 
997 		case COMMAND_COMPLETE:
998 			DB(DB_INTR, printk("CCMP"))
999 			    write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1000 			hostdata->state = S_PRE_CMP_DISC;
1001 			break;
1002 
1003 		case SAVE_POINTERS:
1004 			DB(DB_INTR, printk("SDP"))
1005 			    write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1006 			hostdata->state = S_CONNECTED;
1007 			break;
1008 
1009 		case RESTORE_POINTERS:
1010 			DB(DB_INTR, printk("RDP"))
1011 			    if (hostdata->level2 >= L2_BASIC) {
1012 				write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
1013 				write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
1014 				hostdata->state = S_RUNNING_LEVEL2;
1015 			} else {
1016 				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1017 				hostdata->state = S_CONNECTED;
1018 			}
1019 			break;
1020 
1021 		case DISCONNECT:
1022 			DB(DB_INTR, printk("DIS"))
1023 			    cmd->device->disconnect = 1;
1024 			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1025 			hostdata->state = S_PRE_TMP_DISC;
1026 			break;
1027 
1028 		case MESSAGE_REJECT:
1029 			DB(DB_INTR, printk("REJ"))
1030 #ifdef SYNC_DEBUG
1031 			    printk("-REJ-");
1032 #endif
1033 			if (hostdata->sync_stat[cmd->device->id] == SS_WAITING) {
1034 				hostdata->sync_stat[cmd->device->id] = SS_SET;
1035 				/* we want default_sx_per, not DEFAULT_SX_PER */
1036 				hostdata->sync_xfer[cmd->device->id] =
1037 					calc_sync_xfer(hostdata->default_sx_per
1038 						/ 4, 0, 0, hostdata->sx_table);
1039 			}
1040 			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1041 			hostdata->state = S_CONNECTED;
1042 			break;
1043 
1044 		case EXTENDED_MESSAGE:
1045 			DB(DB_INTR, printk("EXT"))
1046 
1047 			    ucp = hostdata->incoming_msg;
1048 
1049 #ifdef SYNC_DEBUG
1050 			printk("%02x", ucp[hostdata->incoming_ptr]);
1051 #endif
1052 			/* Is this the last byte of the extended message? */
1053 
1054 			if ((hostdata->incoming_ptr >= 2) &&
1055 			    (hostdata->incoming_ptr == (ucp[1] + 1))) {
1056 
1057 				switch (ucp[2]) {	/* what's the EXTENDED code? */
1058 				case EXTENDED_SDTR:
1059 					/* default to default async period */
1060 					id = calc_sync_xfer(hostdata->
1061 							default_sx_per / 4, 0,
1062 							0, hostdata->sx_table);
1063 					if (hostdata->sync_stat[cmd->device->id] !=
1064 					    SS_WAITING) {
1065 
1066 /* A device has sent an unsolicited SDTR message; rather than go
1067  * through the effort of decoding it and then figuring out what
1068  * our reply should be, we're just gonna say that we have a
1069  * synchronous fifo depth of 0. This will result in asynchronous
1070  * transfers - not ideal but so much easier.
1071  * Actually, this is OK because it assures us that if we don't
1072  * specifically ask for sync transfers, we won't do any.
1073  */
1074 
1075 						write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1076 						hostdata->outgoing_msg[0] =
1077 						    EXTENDED_MESSAGE;
1078 						hostdata->outgoing_msg[1] = 3;
1079 						hostdata->outgoing_msg[2] =
1080 						    EXTENDED_SDTR;
1081 						calc_sync_msg(hostdata->
1082 							default_sx_per, 0,
1083 							0, hostdata->outgoing_msg + 3);
1084 						hostdata->outgoing_len = 5;
1085 					} else {
1086 						if (ucp[4]) /* well, sync transfer */
1087 							id = calc_sync_xfer(ucp[3], ucp[4],
1088 									hostdata->fast,
1089 									hostdata->sx_table);
1090 						else if (ucp[3]) /* very unlikely... */
1091 							id = calc_sync_xfer(ucp[3], ucp[4],
1092 									0, hostdata->sx_table);
1093 					}
1094 					hostdata->sync_xfer[cmd->device->id] = id;
1095 #ifdef SYNC_DEBUG
1096 					printk(" sync_xfer=%02x\n",
1097 					       hostdata->sync_xfer[cmd->device->id]);
1098 #endif
1099 					hostdata->sync_stat[cmd->device->id] =
1100 					    SS_SET;
1101 					write_wd33c93_cmd(regs,
1102 							  WD_CMD_NEGATE_ACK);
1103 					hostdata->state = S_CONNECTED;
1104 					break;
1105 				case EXTENDED_WDTR:
1106 					write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1107 					printk("sending WDTR ");
1108 					hostdata->outgoing_msg[0] =
1109 					    EXTENDED_MESSAGE;
1110 					hostdata->outgoing_msg[1] = 2;
1111 					hostdata->outgoing_msg[2] =
1112 					    EXTENDED_WDTR;
1113 					hostdata->outgoing_msg[3] = 0;	/* 8 bit transfer width */
1114 					hostdata->outgoing_len = 4;
1115 					write_wd33c93_cmd(regs,
1116 							  WD_CMD_NEGATE_ACK);
1117 					hostdata->state = S_CONNECTED;
1118 					break;
1119 				default:
1120 					write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1121 					printk
1122 					    ("Rejecting Unknown Extended Message(%02x). ",
1123 					     ucp[2]);
1124 					hostdata->outgoing_msg[0] =
1125 					    MESSAGE_REJECT;
1126 					hostdata->outgoing_len = 1;
1127 					write_wd33c93_cmd(regs,
1128 							  WD_CMD_NEGATE_ACK);
1129 					hostdata->state = S_CONNECTED;
1130 					break;
1131 				}
1132 				hostdata->incoming_ptr = 0;
1133 			}
1134 
1135 			/* We need to read more MESS_IN bytes for the extended message */
1136 
1137 			else {
1138 				hostdata->incoming_ptr++;
1139 				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1140 				hostdata->state = S_CONNECTED;
1141 			}
1142 			break;
1143 
1144 		default:
1145 			printk("Rejecting Unknown Message(%02x) ", msg);
1146 			write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1147 			hostdata->outgoing_msg[0] = MESSAGE_REJECT;
1148 			hostdata->outgoing_len = 1;
1149 			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1150 			hostdata->state = S_CONNECTED;
1151 		}
1152 		spin_unlock_irqrestore(&hostdata->lock, flags);
1153 		break;
1154 
1155 /* Note: this interrupt will occur only after a LEVEL2 command */
1156 
1157 	case CSR_SEL_XFER_DONE:
1158 
1159 /* Make sure that reselection is enabled at this point - it may
1160  * have been turned off for the command that just completed.
1161  */
1162 
1163 		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
1164 		if (phs == 0x60) {
1165 			DB(DB_INTR, printk("SX-DONE"))
1166 			    cmd->SCp.Message = COMMAND_COMPLETE;
1167 			lun = read_wd33c93(regs, WD_TARGET_LUN);
1168 			DB(DB_INTR, printk(":%d.%d", cmd->SCp.Status, lun))
1169 			    hostdata->connected = NULL;
1170 			hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1171 			hostdata->state = S_UNCONNECTED;
1172 			if (cmd->SCp.Status == ILLEGAL_STATUS_BYTE)
1173 				cmd->SCp.Status = lun;
1174 			if (cmd->cmnd[0] == REQUEST_SENSE
1175 			    && cmd->SCp.Status != SAM_STAT_GOOD) {
1176 				set_host_byte(cmd, DID_ERROR);
1177 			} else {
1178 				set_host_byte(cmd, DID_OK);
1179 				scsi_msg_to_host_byte(cmd, cmd->SCp.Message);
1180 				set_status_byte(cmd, cmd->SCp.Status);
1181 			}
1182 			scsi_done(cmd);
1183 
1184 /* We are no longer  connected to a target - check to see if
1185  * there are commands waiting to be executed.
1186  */
1187 			spin_unlock_irqrestore(&hostdata->lock, flags);
1188 			wd33c93_execute(instance);
1189 		} else {
1190 			printk
1191 			    ("%02x:%02x:%02x: Unknown SEL_XFER_DONE phase!!---",
1192 			     asr, sr, phs);
1193 			spin_unlock_irqrestore(&hostdata->lock, flags);
1194 		}
1195 		break;
1196 
1197 /* Note: this interrupt will occur only after a LEVEL2 command */
1198 
1199 	case CSR_SDP:
1200 		DB(DB_INTR, printk("SDP"))
1201 		    hostdata->state = S_RUNNING_LEVEL2;
1202 		write_wd33c93(regs, WD_COMMAND_PHASE, 0x41);
1203 		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
1204 		spin_unlock_irqrestore(&hostdata->lock, flags);
1205 		break;
1206 
1207 	case CSR_XFER_DONE | PHS_MESS_OUT:
1208 	case CSR_UNEXP | PHS_MESS_OUT:
1209 	case CSR_SRV_REQ | PHS_MESS_OUT:
1210 		DB(DB_INTR, printk("MSG_OUT="))
1211 
1212 /* To get here, we've probably requested MESSAGE_OUT and have
1213  * already put the correct bytes in outgoing_msg[] and filled
1214  * in outgoing_len. We simply send them out to the SCSI bus.
1215  * Sometimes we get MESSAGE_OUT phase when we're not expecting
1216  * it - like when our SDTR message is rejected by a target. Some
1217  * targets send the REJECT before receiving all of the extended
1218  * message, and then seem to go back to MESSAGE_OUT for a byte
1219  * or two. Not sure why, or if I'm doing something wrong to
1220  * cause this to happen. Regardless, it seems that sending
1221  * NOP messages in these situations results in no harm and
1222  * makes everyone happy.
1223  */
1224 		    if (hostdata->outgoing_len == 0) {
1225 			hostdata->outgoing_len = 1;
1226 			hostdata->outgoing_msg[0] = NOP;
1227 		}
1228 		transfer_pio(regs, hostdata->outgoing_msg,
1229 			     hostdata->outgoing_len, DATA_OUT_DIR, hostdata);
1230 		DB(DB_INTR, printk("%02x", hostdata->outgoing_msg[0]))
1231 		    hostdata->outgoing_len = 0;
1232 		hostdata->state = S_CONNECTED;
1233 		spin_unlock_irqrestore(&hostdata->lock, flags);
1234 		break;
1235 
1236 	case CSR_UNEXP_DISC:
1237 
1238 /* I think I've seen this after a request-sense that was in response
1239  * to an error condition, but not sure. We certainly need to do
1240  * something when we get this interrupt - the question is 'what?'.
1241  * Let's think positively, and assume some command has finished
1242  * in a legal manner (like a command that provokes a request-sense),
1243  * so we treat it as a normal command-complete-disconnect.
1244  */
1245 
1246 /* Make sure that reselection is enabled at this point - it may
1247  * have been turned off for the command that just completed.
1248  */
1249 
1250 		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
1251 		if (cmd == NULL) {
1252 			printk(" - Already disconnected! ");
1253 			hostdata->state = S_UNCONNECTED;
1254 			spin_unlock_irqrestore(&hostdata->lock, flags);
1255 			return;
1256 		}
1257 		DB(DB_INTR, printk("UNEXP_DISC"))
1258 		    hostdata->connected = NULL;
1259 		hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1260 		hostdata->state = S_UNCONNECTED;
1261 		if (cmd->cmnd[0] == REQUEST_SENSE &&
1262 		    cmd->SCp.Status != SAM_STAT_GOOD) {
1263 			set_host_byte(cmd, DID_ERROR);
1264 		} else {
1265 			set_host_byte(cmd, DID_OK);
1266 			scsi_msg_to_host_byte(cmd, cmd->SCp.Message);
1267 			set_status_byte(cmd, cmd->SCp.Status);
1268 		}
1269 		scsi_done(cmd);
1270 
1271 /* We are no longer connected to a target - check to see if
1272  * there are commands waiting to be executed.
1273  */
1274 		/* look above for comments on scsi_done() */
1275 		spin_unlock_irqrestore(&hostdata->lock, flags);
1276 		wd33c93_execute(instance);
1277 		break;
1278 
1279 	case CSR_DISC:
1280 
1281 /* Make sure that reselection is enabled at this point - it may
1282  * have been turned off for the command that just completed.
1283  */
1284 
1285 		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
1286 		DB(DB_INTR, printk("DISC"))
1287 		    if (cmd == NULL) {
1288 			printk(" - Already disconnected! ");
1289 			hostdata->state = S_UNCONNECTED;
1290 		}
1291 		switch (hostdata->state) {
1292 		case S_PRE_CMP_DISC:
1293 			hostdata->connected = NULL;
1294 			hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1295 			hostdata->state = S_UNCONNECTED;
1296 			DB(DB_INTR, printk(":%d", cmd->SCp.Status))
1297 			if (cmd->cmnd[0] == REQUEST_SENSE
1298 			    && cmd->SCp.Status != SAM_STAT_GOOD) {
1299 				set_host_byte(cmd, DID_ERROR);
1300 			} else {
1301 				set_host_byte(cmd, DID_OK);
1302 				scsi_msg_to_host_byte(cmd, cmd->SCp.Message);
1303 				set_status_byte(cmd, cmd->SCp.Status);
1304 			}
1305 			scsi_done(cmd);
1306 			break;
1307 		case S_PRE_TMP_DISC:
1308 		case S_RUNNING_LEVEL2:
1309 			cmd->host_scribble = (uchar *) hostdata->disconnected_Q;
1310 			hostdata->disconnected_Q = cmd;
1311 			hostdata->connected = NULL;
1312 			hostdata->state = S_UNCONNECTED;
1313 
1314 #ifdef PROC_STATISTICS
1315 			hostdata->disc_done_cnt[cmd->device->id]++;
1316 #endif
1317 
1318 			break;
1319 		default:
1320 			printk("*** Unexpected DISCONNECT interrupt! ***");
1321 			hostdata->state = S_UNCONNECTED;
1322 		}
1323 
1324 /* We are no longer connected to a target - check to see if
1325  * there are commands waiting to be executed.
1326  */
1327 		spin_unlock_irqrestore(&hostdata->lock, flags);
1328 		wd33c93_execute(instance);
1329 		break;
1330 
1331 	case CSR_RESEL_AM:
1332 	case CSR_RESEL:
1333 		DB(DB_INTR, printk("RESEL%s", sr == CSR_RESEL_AM ? "_AM" : ""))
1334 
1335 		    /* Old chips (pre -A ???) don't have advanced features and will
1336 		     * generate CSR_RESEL.  In that case we have to extract the LUN the
1337 		     * hard way (see below).
1338 		     * First we have to make sure this reselection didn't
1339 		     * happen during Arbitration/Selection of some other device.
1340 		     * If yes, put losing command back on top of input_Q.
1341 		     */
1342 		    if (hostdata->level2 <= L2_NONE) {
1343 
1344 			if (hostdata->selecting) {
1345 				cmd = (struct scsi_cmnd *) hostdata->selecting;
1346 				hostdata->selecting = NULL;
1347 				hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1348 				cmd->host_scribble =
1349 				    (uchar *) hostdata->input_Q;
1350 				hostdata->input_Q = cmd;
1351 			}
1352 		}
1353 
1354 		else {
1355 
1356 			if (cmd) {
1357 				if (phs == 0x00) {
1358 					hostdata->busy[cmd->device->id] &=
1359 						~(1 << (cmd->device->lun & 0xff));
1360 					cmd->host_scribble =
1361 					    (uchar *) hostdata->input_Q;
1362 					hostdata->input_Q = cmd;
1363 				} else {
1364 					printk
1365 					    ("---%02x:%02x:%02x-TROUBLE: Intrusive ReSelect!---",
1366 					     asr, sr, phs);
1367 					while (1)
1368 						printk("\r");
1369 				}
1370 			}
1371 
1372 		}
1373 
1374 		/* OK - find out which device reselected us. */
1375 
1376 		id = read_wd33c93(regs, WD_SOURCE_ID);
1377 		id &= SRCID_MASK;
1378 
1379 		/* and extract the lun from the ID message. (Note that we don't
1380 		 * bother to check for a valid message here - I guess this is
1381 		 * not the right way to go, but...)
1382 		 */
1383 
1384 		if (sr == CSR_RESEL_AM) {
1385 			lun = read_wd33c93(regs, WD_DATA);
1386 			if (hostdata->level2 < L2_RESELECT)
1387 				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1388 			lun &= 7;
1389 		} else {
1390 			/* Old chip; wait for msgin phase to pick up the LUN. */
1391 			for (lun = 255; lun; lun--) {
1392 				if ((asr = read_aux_stat(regs)) & ASR_INT)
1393 					break;
1394 				udelay(10);
1395 			}
1396 			if (!(asr & ASR_INT)) {
1397 				printk
1398 				    ("wd33c93: Reselected without IDENTIFY\n");
1399 				lun = 0;
1400 			} else {
1401 				/* Verify this is a change to MSG_IN and read the message */
1402 				sr = read_wd33c93(regs, WD_SCSI_STATUS);
1403 				udelay(7);
1404 				if (sr == (CSR_ABORT | PHS_MESS_IN) ||
1405 				    sr == (CSR_UNEXP | PHS_MESS_IN) ||
1406 				    sr == (CSR_SRV_REQ | PHS_MESS_IN)) {
1407 					/* Got MSG_IN, grab target LUN */
1408 					lun = read_1_byte(regs);
1409 					/* Now we expect a 'paused with ACK asserted' int.. */
1410 					asr = read_aux_stat(regs);
1411 					if (!(asr & ASR_INT)) {
1412 						udelay(10);
1413 						asr = read_aux_stat(regs);
1414 						if (!(asr & ASR_INT))
1415 							printk
1416 							    ("wd33c93: No int after LUN on RESEL (%02x)\n",
1417 							     asr);
1418 					}
1419 					sr = read_wd33c93(regs, WD_SCSI_STATUS);
1420 					udelay(7);
1421 					if (sr != CSR_MSGIN)
1422 						printk
1423 						    ("wd33c93: Not paused with ACK on RESEL (%02x)\n",
1424 						     sr);
1425 					lun &= 7;
1426 					write_wd33c93_cmd(regs,
1427 							  WD_CMD_NEGATE_ACK);
1428 				} else {
1429 					printk
1430 					    ("wd33c93: Not MSG_IN on reselect (%02x)\n",
1431 					     sr);
1432 					lun = 0;
1433 				}
1434 			}
1435 		}
1436 
1437 		/* Now we look for the command that's reconnecting. */
1438 
1439 		cmd = (struct scsi_cmnd *) hostdata->disconnected_Q;
1440 		patch = NULL;
1441 		while (cmd) {
1442 			if (id == cmd->device->id && lun == (u8)cmd->device->lun)
1443 				break;
1444 			patch = cmd;
1445 			cmd = (struct scsi_cmnd *) cmd->host_scribble;
1446 		}
1447 
1448 		/* Hmm. Couldn't find a valid command.... What to do? */
1449 
1450 		if (!cmd) {
1451 			printk
1452 			    ("---TROUBLE: target %d.%d not in disconnect queue---",
1453 			     id, (u8)lun);
1454 			spin_unlock_irqrestore(&hostdata->lock, flags);
1455 			return;
1456 		}
1457 
1458 		/* Ok, found the command - now start it up again. */
1459 
1460 		if (patch)
1461 			patch->host_scribble = cmd->host_scribble;
1462 		else
1463 			hostdata->disconnected_Q =
1464 			    (struct scsi_cmnd *) cmd->host_scribble;
1465 		hostdata->connected = cmd;
1466 
1467 		/* We don't need to worry about 'initialize_SCp()' or 'hostdata->busy[]'
1468 		 * because these things are preserved over a disconnect.
1469 		 * But we DO need to fix the DPD bit so it's correct for this command.
1470 		 */
1471 
1472 		if (cmd->sc_data_direction == DMA_TO_DEVICE)
1473 			write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
1474 		else
1475 			write_wd33c93(regs, WD_DESTINATION_ID,
1476 				      cmd->device->id | DSTID_DPD);
1477 		if (hostdata->level2 >= L2_RESELECT) {
1478 			write_wd33c93_count(regs, 0);	/* we want a DATA_PHASE interrupt */
1479 			write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
1480 			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
1481 			hostdata->state = S_RUNNING_LEVEL2;
1482 		} else
1483 			hostdata->state = S_CONNECTED;
1484 
1485 		    spin_unlock_irqrestore(&hostdata->lock, flags);
1486 		break;
1487 
1488 	default:
1489 		printk("--UNKNOWN INTERRUPT:%02x:%02x:%02x--", asr, sr, phs);
1490 		spin_unlock_irqrestore(&hostdata->lock, flags);
1491 	}
1492 
1493 	DB(DB_INTR, printk("} "))
1494 
1495 }
1496 
1497 static void
1498 reset_wd33c93(struct Scsi_Host *instance)
1499 {
1500 	struct WD33C93_hostdata *hostdata =
1501 	    (struct WD33C93_hostdata *) instance->hostdata;
1502 	const wd33c93_regs regs = hostdata->regs;
1503 	uchar sr;
1504 
1505 #ifdef CONFIG_SGI_IP22
1506 	{
1507 		int busycount = 0;
1508 		extern void sgiwd93_reset(unsigned long);
1509 		/* wait 'til the chip gets some time for us */
1510 		while ((read_aux_stat(regs) & ASR_BSY) && busycount++ < 100)
1511 			udelay (10);
1512 	/*
1513  	 * there are scsi devices out there, which manage to lock up
1514 	 * the wd33c93 in a busy condition. In this state it won't
1515 	 * accept the reset command. The only way to solve this is to
1516  	 * give the chip a hardware reset (if possible). The code below
1517 	 * does this for the SGI Indy, where this is possible
1518 	 */
1519 	/* still busy ? */
1520 	if (read_aux_stat(regs) & ASR_BSY)
1521 		sgiwd93_reset(instance->base); /* yeah, give it the hard one */
1522 	}
1523 #endif
1524 
1525 	write_wd33c93(regs, WD_OWN_ID, OWNID_EAF | OWNID_RAF |
1526 		      instance->this_id | hostdata->clock_freq);
1527 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
1528 	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
1529 		      calc_sync_xfer(hostdata->default_sx_per / 4,
1530 				     DEFAULT_SX_OFF, 0, hostdata->sx_table));
1531 	write_wd33c93(regs, WD_COMMAND, WD_CMD_RESET);
1532 
1533 
1534 #ifdef CONFIG_MVME147_SCSI
1535 	udelay(25);		/* The old wd33c93 on MVME147 needs this, at least */
1536 #endif
1537 
1538 	while (!(read_aux_stat(regs) & ASR_INT))
1539 		;
1540 	sr = read_wd33c93(regs, WD_SCSI_STATUS);
1541 
1542 	hostdata->microcode = read_wd33c93(regs, WD_CDB_1);
1543 	if (sr == 0x00)
1544 		hostdata->chip = C_WD33C93;
1545 	else if (sr == 0x01) {
1546 		write_wd33c93(regs, WD_QUEUE_TAG, 0xa5);	/* any random number */
1547 		sr = read_wd33c93(regs, WD_QUEUE_TAG);
1548 		if (sr == 0xa5) {
1549 			hostdata->chip = C_WD33C93B;
1550 			write_wd33c93(regs, WD_QUEUE_TAG, 0);
1551 		} else
1552 			hostdata->chip = C_WD33C93A;
1553 	} else
1554 		hostdata->chip = C_UNKNOWN_CHIP;
1555 
1556 	if (hostdata->chip != C_WD33C93B)	/* Fast SCSI unavailable */
1557 		hostdata->fast = 0;
1558 
1559 	write_wd33c93(regs, WD_TIMEOUT_PERIOD, TIMEOUT_PERIOD_VALUE);
1560 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
1561 }
1562 
1563 int
1564 wd33c93_host_reset(struct scsi_cmnd * SCpnt)
1565 {
1566 	struct Scsi_Host *instance;
1567 	struct WD33C93_hostdata *hostdata;
1568 	int i;
1569 
1570 	instance = SCpnt->device->host;
1571 	spin_lock_irq(instance->host_lock);
1572 	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1573 
1574 	printk("scsi%d: reset. ", instance->host_no);
1575 	disable_irq(instance->irq);
1576 
1577 	hostdata->dma_stop(instance, NULL, 0);
1578 	for (i = 0; i < 8; i++) {
1579 		hostdata->busy[i] = 0;
1580 		hostdata->sync_xfer[i] =
1581 			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
1582 					0, hostdata->sx_table);
1583 		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
1584 	}
1585 	hostdata->input_Q = NULL;
1586 	hostdata->selecting = NULL;
1587 	hostdata->connected = NULL;
1588 	hostdata->disconnected_Q = NULL;
1589 	hostdata->state = S_UNCONNECTED;
1590 	hostdata->dma = D_DMA_OFF;
1591 	hostdata->incoming_ptr = 0;
1592 	hostdata->outgoing_len = 0;
1593 
1594 	reset_wd33c93(instance);
1595 	SCpnt->result = DID_RESET << 16;
1596 	enable_irq(instance->irq);
1597 	spin_unlock_irq(instance->host_lock);
1598 	return SUCCESS;
1599 }
1600 
1601 int
1602 wd33c93_abort(struct scsi_cmnd * cmd)
1603 {
1604 	struct Scsi_Host *instance;
1605 	struct WD33C93_hostdata *hostdata;
1606 	wd33c93_regs regs;
1607 	struct scsi_cmnd *tmp, *prev;
1608 
1609 	disable_irq(cmd->device->host->irq);
1610 
1611 	instance = cmd->device->host;
1612 	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1613 	regs = hostdata->regs;
1614 
1615 /*
1616  * Case 1 : If the command hasn't been issued yet, we simply remove it
1617  *     from the input_Q.
1618  */
1619 
1620 	tmp = (struct scsi_cmnd *) hostdata->input_Q;
1621 	prev = NULL;
1622 	while (tmp) {
1623 		if (tmp == cmd) {
1624 			if (prev)
1625 				prev->host_scribble = cmd->host_scribble;
1626 			else
1627 				hostdata->input_Q =
1628 				    (struct scsi_cmnd *) cmd->host_scribble;
1629 			cmd->host_scribble = NULL;
1630 			cmd->result = DID_ABORT << 16;
1631 			printk
1632 			    ("scsi%d: Abort - removing command from input_Q. ",
1633 			     instance->host_no);
1634 			enable_irq(cmd->device->host->irq);
1635 			scsi_done(cmd);
1636 			return SUCCESS;
1637 		}
1638 		prev = tmp;
1639 		tmp = (struct scsi_cmnd *) tmp->host_scribble;
1640 	}
1641 
1642 /*
1643  * Case 2 : If the command is connected, we're going to fail the abort
1644  *     and let the high level SCSI driver retry at a later time or
1645  *     issue a reset.
1646  *
1647  *     Timeouts, and therefore aborted commands, will be highly unlikely
1648  *     and handling them cleanly in this situation would make the common
1649  *     case of noresets less efficient, and would pollute our code.  So,
1650  *     we fail.
1651  */
1652 
1653 	if (hostdata->connected == cmd) {
1654 		uchar sr, asr;
1655 		unsigned long timeout;
1656 
1657 		printk("scsi%d: Aborting connected command - ",
1658 		       instance->host_no);
1659 
1660 		printk("stopping DMA - ");
1661 		if (hostdata->dma == D_DMA_RUNNING) {
1662 			hostdata->dma_stop(instance, cmd, 0);
1663 			hostdata->dma = D_DMA_OFF;
1664 		}
1665 
1666 		printk("sending wd33c93 ABORT command - ");
1667 		write_wd33c93(regs, WD_CONTROL,
1668 			      CTRL_IDI | CTRL_EDI | CTRL_POLLED);
1669 		write_wd33c93_cmd(regs, WD_CMD_ABORT);
1670 
1671 /* Now we have to attempt to flush out the FIFO... */
1672 
1673 		printk("flushing fifo - ");
1674 		timeout = 1000000;
1675 		do {
1676 			asr = read_aux_stat(regs);
1677 			if (asr & ASR_DBR)
1678 				read_wd33c93(regs, WD_DATA);
1679 		} while (!(asr & ASR_INT) && timeout-- > 0);
1680 		sr = read_wd33c93(regs, WD_SCSI_STATUS);
1681 		printk
1682 		    ("asr=%02x, sr=%02x, %ld bytes un-transferred (timeout=%ld) - ",
1683 		     asr, sr, read_wd33c93_count(regs), timeout);
1684 
1685 		/*
1686 		 * Abort command processed.
1687 		 * Still connected.
1688 		 * We must disconnect.
1689 		 */
1690 
1691 		printk("sending wd33c93 DISCONNECT command - ");
1692 		write_wd33c93_cmd(regs, WD_CMD_DISCONNECT);
1693 
1694 		timeout = 1000000;
1695 		asr = read_aux_stat(regs);
1696 		while ((asr & ASR_CIP) && timeout-- > 0)
1697 			asr = read_aux_stat(regs);
1698 		sr = read_wd33c93(regs, WD_SCSI_STATUS);
1699 		printk("asr=%02x, sr=%02x.", asr, sr);
1700 
1701 		hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1702 		hostdata->connected = NULL;
1703 		hostdata->state = S_UNCONNECTED;
1704 		cmd->result = DID_ABORT << 16;
1705 
1706 /*      sti();*/
1707 		wd33c93_execute(instance);
1708 
1709 		enable_irq(cmd->device->host->irq);
1710 		scsi_done(cmd);
1711 		return SUCCESS;
1712 	}
1713 
1714 /*
1715  * Case 3: If the command is currently disconnected from the bus,
1716  * we're not going to expend much effort here: Let's just return
1717  * an ABORT_SNOOZE and hope for the best...
1718  */
1719 
1720 	tmp = (struct scsi_cmnd *) hostdata->disconnected_Q;
1721 	while (tmp) {
1722 		if (tmp == cmd) {
1723 			printk
1724 			    ("scsi%d: Abort - command found on disconnected_Q - ",
1725 			     instance->host_no);
1726 			printk("Abort SNOOZE. ");
1727 			enable_irq(cmd->device->host->irq);
1728 			return FAILED;
1729 		}
1730 		tmp = (struct scsi_cmnd *) tmp->host_scribble;
1731 	}
1732 
1733 /*
1734  * Case 4 : If we reached this point, the command was not found in any of
1735  *     the queues.
1736  *
1737  * We probably reached this point because of an unlikely race condition
1738  * between the command completing successfully and the abortion code,
1739  * so we won't panic, but we will notify the user in case something really
1740  * broke.
1741  */
1742 
1743 /*   sti();*/
1744 	wd33c93_execute(instance);
1745 
1746 	enable_irq(cmd->device->host->irq);
1747 	printk("scsi%d: warning : SCSI command probably completed successfully"
1748 	       "         before abortion. ", instance->host_no);
1749 	return FAILED;
1750 }
1751 
1752 #define MAX_WD33C93_HOSTS 4
1753 #define MAX_SETUP_ARGS ARRAY_SIZE(setup_args)
1754 #define SETUP_BUFFER_SIZE 200
1755 static char setup_buffer[SETUP_BUFFER_SIZE];
1756 static char setup_used[MAX_SETUP_ARGS];
1757 static int done_setup = 0;
1758 
1759 static int
1760 wd33c93_setup(char *str)
1761 {
1762 	int i;
1763 	char *p1, *p2;
1764 
1765 	/* The kernel does some processing of the command-line before calling
1766 	 * this function: If it begins with any decimal or hex number arguments,
1767 	 * ints[0] = how many numbers found and ints[1] through [n] are the values
1768 	 * themselves. str points to where the non-numeric arguments (if any)
1769 	 * start: We do our own parsing of those. We construct synthetic 'nosync'
1770 	 * keywords out of numeric args (to maintain compatibility with older
1771 	 * versions) and then add the rest of the arguments.
1772 	 */
1773 
1774 	p1 = setup_buffer;
1775 	*p1 = '\0';
1776 	if (str)
1777 		strncpy(p1, str, SETUP_BUFFER_SIZE - strlen(setup_buffer));
1778 	setup_buffer[SETUP_BUFFER_SIZE - 1] = '\0';
1779 	p1 = setup_buffer;
1780 	i = 0;
1781 	while (*p1 && (i < MAX_SETUP_ARGS)) {
1782 		p2 = strchr(p1, ',');
1783 		if (p2) {
1784 			*p2 = '\0';
1785 			if (p1 != p2)
1786 				setup_args[i] = p1;
1787 			p1 = p2 + 1;
1788 			i++;
1789 		} else {
1790 			setup_args[i] = p1;
1791 			break;
1792 		}
1793 	}
1794 	for (i = 0; i < MAX_SETUP_ARGS; i++)
1795 		setup_used[i] = 0;
1796 	done_setup = 1;
1797 
1798 	return 1;
1799 }
1800 __setup("wd33c93=", wd33c93_setup);
1801 
1802 /* check_setup_args() returns index if key found, 0 if not
1803  */
1804 static int
1805 check_setup_args(char *key, int *flags, int *val, char *buf)
1806 {
1807 	int x;
1808 	char *cp;
1809 
1810 	for (x = 0; x < MAX_SETUP_ARGS; x++) {
1811 		if (setup_used[x])
1812 			continue;
1813 		if (!strncmp(setup_args[x], key, strlen(key)))
1814 			break;
1815 		if (!strncmp(setup_args[x], "next", strlen("next")))
1816 			return 0;
1817 	}
1818 	if (x == MAX_SETUP_ARGS)
1819 		return 0;
1820 	setup_used[x] = 1;
1821 	cp = setup_args[x] + strlen(key);
1822 	*val = -1;
1823 	if (*cp != ':')
1824 		return ++x;
1825 	cp++;
1826 	if ((*cp >= '0') && (*cp <= '9')) {
1827 		*val = simple_strtoul(cp, NULL, 0);
1828 	}
1829 	return ++x;
1830 }
1831 
1832 /*
1833  * Calculate internal data-transfer-clock cycle from input-clock
1834  * frequency (/MHz) and fill 'sx_table'.
1835  *
1836  * The original driver used to rely on a fixed sx_table, containing periods
1837  * for (only) the lower limits of the respective input-clock-frequency ranges
1838  * (8-10/12-15/16-20 MHz). Although it seems, that no problems occurred with
1839  * this setting so far, it might be desirable to adjust the transfer periods
1840  * closer to the really attached, possibly 25% higher, input-clock, since
1841  * - the wd33c93 may really use a significant shorter period, than it has
1842  *   negotiated (eg. thrashing the target, which expects 4/8MHz, with 5/10MHz
1843  *   instead).
1844  * - the wd33c93 may ask the target for a lower transfer rate, than the target
1845  *   is capable of (eg. negotiating for an assumed minimum of 252ns instead of
1846  *   possible 200ns, which indeed shows up in tests as an approx. 10% lower
1847  *   transfer rate).
1848  */
1849 static inline unsigned int
1850 round_4(unsigned int x)
1851 {
1852 	switch (x & 3) {
1853 		case 1: --x;
1854 			break;
1855 		case 2: ++x;
1856 			fallthrough;
1857 		case 3: ++x;
1858 	}
1859 	return x;
1860 }
1861 
1862 static void
1863 calc_sx_table(unsigned int mhz, struct sx_period sx_table[9])
1864 {
1865 	unsigned int d, i;
1866 	if (mhz < 11)
1867 		d = 2;	/* divisor for  8-10 MHz input-clock */
1868 	else if (mhz < 16)
1869 		d = 3;	/* divisor for 12-15 MHz input-clock */
1870 	else
1871 		d = 4;	/* divisor for 16-20 MHz input-clock */
1872 
1873 	d = (100000 * d) / 2 / mhz; /* 100 x DTCC / nanosec */
1874 
1875 	sx_table[0].period_ns = 1;
1876 	sx_table[0].reg_value = 0x20;
1877 	for (i = 1; i < 8; i++) {
1878 		sx_table[i].period_ns = round_4((i+1)*d / 100);
1879 		sx_table[i].reg_value = (i+1)*0x10;
1880 	}
1881 	sx_table[7].reg_value = 0;
1882 	sx_table[8].period_ns = 0;
1883 	sx_table[8].reg_value = 0;
1884 }
1885 
1886 /*
1887  * check and, maybe, map an init- or "clock:"- argument.
1888  */
1889 static uchar
1890 set_clk_freq(int freq, int *mhz)
1891 {
1892 	int x = freq;
1893 	if (WD33C93_FS_8_10 == freq)
1894 		freq = 8;
1895 	else if (WD33C93_FS_12_15 == freq)
1896 		freq = 12;
1897 	else if (WD33C93_FS_16_20 == freq)
1898 		freq = 16;
1899 	else if (freq > 7 && freq < 11)
1900 		x = WD33C93_FS_8_10;
1901 		else if (freq > 11 && freq < 16)
1902 		x = WD33C93_FS_12_15;
1903 		else if (freq > 15 && freq < 21)
1904 		x = WD33C93_FS_16_20;
1905 	else {
1906 			/* Hmm, wouldn't it be safer to assume highest freq here? */
1907 		x = WD33C93_FS_8_10;
1908 		freq = 8;
1909 	}
1910 	*mhz = freq;
1911 	return x;
1912 }
1913 
1914 /*
1915  * to be used with the resync: fast: ... options
1916  */
1917 static inline void set_resync ( struct WD33C93_hostdata *hd, int mask )
1918 {
1919 	int i;
1920 	for (i = 0; i < 8; i++)
1921 		if (mask & (1 << i))
1922 			hd->sync_stat[i] = SS_UNSET;
1923 }
1924 
1925 void
1926 wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs,
1927 	     dma_setup_t setup, dma_stop_t stop, int clock_freq)
1928 {
1929 	struct WD33C93_hostdata *hostdata;
1930 	int i;
1931 	int flags;
1932 	int val;
1933 	char buf[32];
1934 
1935 	if (!done_setup && setup_strings)
1936 		wd33c93_setup(setup_strings);
1937 
1938 	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1939 
1940 	hostdata->regs = regs;
1941 	hostdata->clock_freq = set_clk_freq(clock_freq, &i);
1942 	calc_sx_table(i, hostdata->sx_table);
1943 	hostdata->dma_setup = setup;
1944 	hostdata->dma_stop = stop;
1945 	hostdata->dma_bounce_buffer = NULL;
1946 	hostdata->dma_bounce_len = 0;
1947 	for (i = 0; i < 8; i++) {
1948 		hostdata->busy[i] = 0;
1949 		hostdata->sync_xfer[i] =
1950 			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
1951 					0, hostdata->sx_table);
1952 		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
1953 #ifdef PROC_STATISTICS
1954 		hostdata->cmd_cnt[i] = 0;
1955 		hostdata->disc_allowed_cnt[i] = 0;
1956 		hostdata->disc_done_cnt[i] = 0;
1957 #endif
1958 	}
1959 	hostdata->input_Q = NULL;
1960 	hostdata->selecting = NULL;
1961 	hostdata->connected = NULL;
1962 	hostdata->disconnected_Q = NULL;
1963 	hostdata->state = S_UNCONNECTED;
1964 	hostdata->dma = D_DMA_OFF;
1965 	hostdata->level2 = L2_BASIC;
1966 	hostdata->disconnect = DIS_ADAPTIVE;
1967 	hostdata->args = DEBUG_DEFAULTS;
1968 	hostdata->incoming_ptr = 0;
1969 	hostdata->outgoing_len = 0;
1970 	hostdata->default_sx_per = DEFAULT_SX_PER;
1971 	hostdata->no_dma = 0;	/* default is DMA enabled */
1972 
1973 #ifdef PROC_INTERFACE
1974 	hostdata->proc = PR_VERSION | PR_INFO | PR_STATISTICS |
1975 	    PR_CONNECTED | PR_INPUTQ | PR_DISCQ | PR_STOP;
1976 #ifdef PROC_STATISTICS
1977 	hostdata->dma_cnt = 0;
1978 	hostdata->pio_cnt = 0;
1979 	hostdata->int_cnt = 0;
1980 #endif
1981 #endif
1982 
1983 	if (check_setup_args("clock", &flags, &val, buf)) {
1984 		hostdata->clock_freq = set_clk_freq(val, &val);
1985 		calc_sx_table(val, hostdata->sx_table);
1986 	}
1987 
1988 	if (check_setup_args("nosync", &flags, &val, buf))
1989 		hostdata->no_sync = val;
1990 
1991 	if (check_setup_args("nodma", &flags, &val, buf))
1992 		hostdata->no_dma = (val == -1) ? 1 : val;
1993 
1994 	if (check_setup_args("period", &flags, &val, buf))
1995 		hostdata->default_sx_per =
1996 		    hostdata->sx_table[round_period((unsigned int) val,
1997 		                                    hostdata->sx_table)].period_ns;
1998 
1999 	if (check_setup_args("disconnect", &flags, &val, buf)) {
2000 		if ((val >= DIS_NEVER) && (val <= DIS_ALWAYS))
2001 			hostdata->disconnect = val;
2002 		else
2003 			hostdata->disconnect = DIS_ADAPTIVE;
2004 	}
2005 
2006 	if (check_setup_args("level2", &flags, &val, buf))
2007 		hostdata->level2 = val;
2008 
2009 	if (check_setup_args("debug", &flags, &val, buf))
2010 		hostdata->args = val & DB_MASK;
2011 
2012 	if (check_setup_args("burst", &flags, &val, buf))
2013 		hostdata->dma_mode = val ? CTRL_BURST:CTRL_DMA;
2014 
2015 	if (WD33C93_FS_16_20 == hostdata->clock_freq /* divisor 4 */
2016 		&& check_setup_args("fast", &flags, &val, buf))
2017 		hostdata->fast = !!val;
2018 
2019 	if ((i = check_setup_args("next", &flags, &val, buf))) {
2020 		while (i)
2021 			setup_used[--i] = 1;
2022 	}
2023 #ifdef PROC_INTERFACE
2024 	if (check_setup_args("proc", &flags, &val, buf))
2025 		hostdata->proc = val;
2026 #endif
2027 
2028 	spin_lock_irq(&hostdata->lock);
2029 	reset_wd33c93(instance);
2030 	spin_unlock_irq(&hostdata->lock);
2031 
2032 	printk("wd33c93-%d: chip=%s/%d no_sync=0x%x no_dma=%d",
2033 	       instance->host_no,
2034 	       (hostdata->chip == C_WD33C93) ? "WD33c93" : (hostdata->chip ==
2035 							    C_WD33C93A) ?
2036 	       "WD33c93A" : (hostdata->chip ==
2037 			     C_WD33C93B) ? "WD33c93B" : "unknown",
2038 	       hostdata->microcode, hostdata->no_sync, hostdata->no_dma);
2039 #ifdef DEBUGGING_ON
2040 	printk(" debug_flags=0x%02x\n", hostdata->args);
2041 #else
2042 	printk(" debugging=OFF\n");
2043 #endif
2044 	printk("           setup_args=");
2045 	for (i = 0; i < MAX_SETUP_ARGS; i++)
2046 		printk("%s,", setup_args[i]);
2047 	printk("\n");
2048 	printk("           Version %s - %s\n", WD33C93_VERSION, WD33C93_DATE);
2049 }
2050 
2051 int wd33c93_write_info(struct Scsi_Host *instance, char *buf, int len)
2052 {
2053 #ifdef PROC_INTERFACE
2054 	char *bp;
2055 	struct WD33C93_hostdata *hd;
2056 	int x;
2057 
2058 	hd = (struct WD33C93_hostdata *) instance->hostdata;
2059 
2060 /* We accept the following
2061  * keywords (same format as command-line, but arguments are not optional):
2062  *    debug
2063  *    disconnect
2064  *    period
2065  *    resync
2066  *    proc
2067  *    nodma
2068  *    level2
2069  *    burst
2070  *    fast
2071  *    nosync
2072  */
2073 
2074 	buf[len] = '\0';
2075 	for (bp = buf; *bp; ) {
2076 		while (',' == *bp || ' ' == *bp)
2077 			++bp;
2078 	if (!strncmp(bp, "debug:", 6)) {
2079 			hd->args = simple_strtoul(bp+6, &bp, 0) & DB_MASK;
2080 	} else if (!strncmp(bp, "disconnect:", 11)) {
2081 			x = simple_strtoul(bp+11, &bp, 0);
2082 		if (x < DIS_NEVER || x > DIS_ALWAYS)
2083 			x = DIS_ADAPTIVE;
2084 		hd->disconnect = x;
2085 	} else if (!strncmp(bp, "period:", 7)) {
2086 		x = simple_strtoul(bp+7, &bp, 0);
2087 		hd->default_sx_per =
2088 			hd->sx_table[round_period((unsigned int) x,
2089 						  hd->sx_table)].period_ns;
2090 	} else if (!strncmp(bp, "resync:", 7)) {
2091 			set_resync(hd, (int)simple_strtoul(bp+7, &bp, 0));
2092 	} else if (!strncmp(bp, "proc:", 5)) {
2093 			hd->proc = simple_strtoul(bp+5, &bp, 0);
2094 	} else if (!strncmp(bp, "nodma:", 6)) {
2095 			hd->no_dma = simple_strtoul(bp+6, &bp, 0);
2096 	} else if (!strncmp(bp, "level2:", 7)) {
2097 			hd->level2 = simple_strtoul(bp+7, &bp, 0);
2098 		} else if (!strncmp(bp, "burst:", 6)) {
2099 			hd->dma_mode =
2100 				simple_strtol(bp+6, &bp, 0) ? CTRL_BURST:CTRL_DMA;
2101 		} else if (!strncmp(bp, "fast:", 5)) {
2102 			x = !!simple_strtol(bp+5, &bp, 0);
2103 			if (x != hd->fast)
2104 				set_resync(hd, 0xff);
2105 			hd->fast = x;
2106 		} else if (!strncmp(bp, "nosync:", 7)) {
2107 			x = simple_strtoul(bp+7, &bp, 0);
2108 			set_resync(hd, x ^ hd->no_sync);
2109 			hd->no_sync = x;
2110 		} else {
2111 			break; /* unknown keyword,syntax-error,... */
2112 		}
2113 	}
2114 	return len;
2115 #else
2116 	return 0;
2117 #endif
2118 }
2119 
2120 int
2121 wd33c93_show_info(struct seq_file *m, struct Scsi_Host *instance)
2122 {
2123 #ifdef PROC_INTERFACE
2124 	struct WD33C93_hostdata *hd;
2125 	struct scsi_cmnd *cmd;
2126 	int x;
2127 
2128 	hd = (struct WD33C93_hostdata *) instance->hostdata;
2129 
2130 	spin_lock_irq(&hd->lock);
2131 	if (hd->proc & PR_VERSION)
2132 		seq_printf(m, "\nVersion %s - %s.",
2133 			WD33C93_VERSION, WD33C93_DATE);
2134 
2135 	if (hd->proc & PR_INFO) {
2136 		seq_printf(m, "\nclock_freq=%02x no_sync=%02x no_dma=%d"
2137 			" dma_mode=%02x fast=%d",
2138 			hd->clock_freq, hd->no_sync, hd->no_dma, hd->dma_mode, hd->fast);
2139 		seq_puts(m, "\nsync_xfer[] =       ");
2140 		for (x = 0; x < 7; x++)
2141 			seq_printf(m, "\t%02x", hd->sync_xfer[x]);
2142 		seq_puts(m, "\nsync_stat[] =       ");
2143 		for (x = 0; x < 7; x++)
2144 			seq_printf(m, "\t%02x", hd->sync_stat[x]);
2145 	}
2146 #ifdef PROC_STATISTICS
2147 	if (hd->proc & PR_STATISTICS) {
2148 		seq_puts(m, "\ncommands issued:    ");
2149 		for (x = 0; x < 7; x++)
2150 			seq_printf(m, "\t%ld", hd->cmd_cnt[x]);
2151 		seq_puts(m, "\ndisconnects allowed:");
2152 		for (x = 0; x < 7; x++)
2153 			seq_printf(m, "\t%ld", hd->disc_allowed_cnt[x]);
2154 		seq_puts(m, "\ndisconnects done:   ");
2155 		for (x = 0; x < 7; x++)
2156 			seq_printf(m, "\t%ld", hd->disc_done_cnt[x]);
2157 		seq_printf(m,
2158 			"\ninterrupts: %ld, DATA_PHASE ints: %ld DMA, %ld PIO",
2159 			hd->int_cnt, hd->dma_cnt, hd->pio_cnt);
2160 	}
2161 #endif
2162 	if (hd->proc & PR_CONNECTED) {
2163 		seq_puts(m, "\nconnected:     ");
2164 		if (hd->connected) {
2165 			cmd = (struct scsi_cmnd *) hd->connected;
2166 			seq_printf(m, " %d:%llu(%02x)",
2167 				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2168 		}
2169 	}
2170 	if (hd->proc & PR_INPUTQ) {
2171 		seq_puts(m, "\ninput_Q:       ");
2172 		cmd = (struct scsi_cmnd *) hd->input_Q;
2173 		while (cmd) {
2174 			seq_printf(m, " %d:%llu(%02x)",
2175 				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2176 			cmd = (struct scsi_cmnd *) cmd->host_scribble;
2177 		}
2178 	}
2179 	if (hd->proc & PR_DISCQ) {
2180 		seq_puts(m, "\ndisconnected_Q:");
2181 		cmd = (struct scsi_cmnd *) hd->disconnected_Q;
2182 		while (cmd) {
2183 			seq_printf(m, " %d:%llu(%02x)",
2184 				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2185 			cmd = (struct scsi_cmnd *) cmd->host_scribble;
2186 		}
2187 	}
2188 	seq_putc(m, '\n');
2189 	spin_unlock_irq(&hd->lock);
2190 #endif				/* PROC_INTERFACE */
2191 	return 0;
2192 }
2193 
2194 EXPORT_SYMBOL(wd33c93_host_reset);
2195 EXPORT_SYMBOL(wd33c93_init);
2196 EXPORT_SYMBOL(wd33c93_abort);
2197 EXPORT_SYMBOL(wd33c93_queuecommand);
2198 EXPORT_SYMBOL(wd33c93_intr);
2199 EXPORT_SYMBOL(wd33c93_show_info);
2200 EXPORT_SYMBOL(wd33c93_write_info);
2201