xref: /linux/drivers/scsi/wd33c93.c (revision 7234e2ea0edd00bfb6bb2159e55878c19885ce68)
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 static inline uchar
read_wd33c93(const wd33c93_regs regs,uchar reg_num)166 read_wd33c93(const wd33c93_regs regs, uchar reg_num)
167 {
168 	*regs.SASR = reg_num;
169 	mb();
170 	return (*regs.SCMD);
171 }
172 
173 static unsigned long
read_wd33c93_count(const wd33c93_regs regs)174 read_wd33c93_count(const wd33c93_regs regs)
175 {
176 	unsigned long value;
177 
178 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
179 	mb();
180 	value = *regs.SCMD << 16;
181 	value |= *regs.SCMD << 8;
182 	value |= *regs.SCMD;
183 	mb();
184 	return value;
185 }
186 
187 static inline uchar
read_aux_stat(const wd33c93_regs regs)188 read_aux_stat(const wd33c93_regs regs)
189 {
190 	return *regs.SASR;
191 }
192 
193 static inline void
write_wd33c93(const wd33c93_regs regs,uchar reg_num,uchar value)194 write_wd33c93(const wd33c93_regs regs, uchar reg_num, uchar value)
195 {
196 	*regs.SASR = reg_num;
197 	mb();
198 	*regs.SCMD = value;
199 	mb();
200 }
201 
202 static void
write_wd33c93_count(const wd33c93_regs regs,unsigned long value)203 write_wd33c93_count(const wd33c93_regs regs, unsigned long value)
204 {
205 	*regs.SASR = WD_TRANSFER_COUNT_MSB;
206 	mb();
207 	*regs.SCMD = value >> 16;
208 	*regs.SCMD = value >> 8;
209 	*regs.SCMD = value;
210 	mb();
211 }
212 
213 static inline void
write_wd33c93_cmd(const wd33c93_regs regs,uchar cmd)214 write_wd33c93_cmd(const wd33c93_regs regs, uchar cmd)
215 {
216 	*regs.SASR = WD_COMMAND;
217 	mb();
218 	*regs.SCMD = cmd;
219 	mb();
220 }
221 
222 static inline void
write_wd33c93_cdb(const wd33c93_regs regs,uint len,uchar cmnd[])223 write_wd33c93_cdb(const wd33c93_regs regs, uint len, uchar cmnd[])
224 {
225 	int i;
226 
227 	*regs.SASR = WD_CDB_1;
228 	for (i = 0; i < len; i++)
229 		*regs.SCMD = cmnd[i];
230 }
231 
232 static inline uchar
read_1_byte(const wd33c93_regs regs)233 read_1_byte(const wd33c93_regs regs)
234 {
235 	uchar asr;
236 	uchar x = 0;
237 
238 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
239 	write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO | 0x80);
240 	do {
241 		asr = read_aux_stat(regs);
242 		if (asr & ASR_DBR)
243 			x = read_wd33c93(regs, WD_DATA);
244 	} while (!(asr & ASR_INT));
245 	return x;
246 }
247 
248 static int
round_period(unsigned int period,const struct sx_period * sx_table)249 round_period(unsigned int period, const struct sx_period *sx_table)
250 {
251 	int x;
252 
253 	for (x = 1; sx_table[x].period_ns; x++) {
254 		if ((period <= sx_table[x - 0].period_ns) &&
255 		    (period > sx_table[x - 1].period_ns)) {
256 			return x;
257 		}
258 	}
259 	return 7;
260 }
261 
262 /*
263  * Calculate Synchronous Transfer Register value from SDTR code.
264  */
265 static uchar
calc_sync_xfer(unsigned int period,unsigned int offset,unsigned int fast,const struct sx_period * sx_table)266 calc_sync_xfer(unsigned int period, unsigned int offset, unsigned int fast,
267                const struct sx_period *sx_table)
268 {
269 	/* When doing Fast SCSI synchronous data transfers, the corresponding
270 	 * value in 'sx_table' is two times the actually used transfer period.
271 	 */
272 	uchar result;
273 
274 	if (offset && fast) {
275 		fast = STR_FSS;
276 		period *= 2;
277 	} else {
278 		fast = 0;
279 	}
280 	period *= 4;		/* convert SDTR code to ns */
281 	result = sx_table[round_period(period,sx_table)].reg_value;
282 	result |= (offset < OPTIMUM_SX_OFF) ? offset : OPTIMUM_SX_OFF;
283 	result |= fast;
284 	return result;
285 }
286 
287 /*
288  * Calculate SDTR code bytes [3],[4] from period and offset.
289  */
290 static inline void
calc_sync_msg(unsigned int period,unsigned int offset,unsigned int fast,uchar msg[2])291 calc_sync_msg(unsigned int period, unsigned int offset, unsigned int fast,
292                 uchar  msg[2])
293 {
294 	/* 'period' is a "normal"-mode value, like the ones in 'sx_table'. The
295 	 * actually used transfer period for Fast SCSI synchronous data
296 	 * transfers is half that value.
297 	 */
298 	period /= 4;
299 	if (offset && fast)
300 		period /= 2;
301 	msg[0] = period;
302 	msg[1] = offset;
303 }
304 
wd33c93_queuecommand_lck(struct scsi_cmnd * cmd)305 static int wd33c93_queuecommand_lck(struct scsi_cmnd *cmd)
306 {
307 	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
308 	struct WD33C93_hostdata *hostdata;
309 	struct scsi_cmnd *tmp;
310 
311 	hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
312 
313 	DB(DB_QUEUE_COMMAND,
314 	   printk("Q-%d-%02x( ", cmd->device->id, cmd->cmnd[0]))
315 
316 /* Set up a few fields in the scsi_cmnd structure for our own use:
317  *  - host_scribble is the pointer to the next cmd in the input queue
318  *  - result is what you'd expect
319  */
320 	cmd->host_scribble = NULL;
321 	cmd->result = 0;
322 
323 /* We use the Scsi_Pointer structure that's included with each command
324  * as a scratchpad (as it's intended to be used!). The handy thing about
325  * the SCp.xxx fields is that they're always associated with a given
326  * cmd, and are preserved across disconnect-reselect. This means we
327  * can pretty much ignore SAVE_POINTERS and RESTORE_POINTERS messages
328  * if we keep all the critical pointers and counters in SCp:
329  *  - SCp.ptr is the pointer into the RAM buffer
330  *  - SCp.this_residual is the size of that buffer
331  *  - SCp.buffer points to the current scatter-gather buffer
332  *  - SCp.buffers_residual tells us how many S.G. buffers there are
333  *  - SCp.have_data_in is not used
334  *  - SCp.sent_command is not used
335  *  - SCp.phase records this command's SRCID_ER bit setting
336  */
337 
338 	if (scsi_bufflen(cmd)) {
339 		scsi_pointer->buffer = scsi_sglist(cmd);
340 		scsi_pointer->buffers_residual = scsi_sg_count(cmd) - 1;
341 		scsi_pointer->ptr = sg_virt(scsi_pointer->buffer);
342 		scsi_pointer->this_residual = scsi_pointer->buffer->length;
343 	} else {
344 		scsi_pointer->buffer = NULL;
345 		scsi_pointer->buffers_residual = 0;
346 		scsi_pointer->ptr = NULL;
347 		scsi_pointer->this_residual = 0;
348 	}
349 
350 /* WD docs state that at the conclusion of a "LEVEL2" command, the
351  * status byte can be retrieved from the LUN register. Apparently,
352  * this is the case only for *uninterrupted* LEVEL2 commands! If
353  * there are any unexpected phases entered, even if they are 100%
354  * legal (different devices may choose to do things differently),
355  * the LEVEL2 command sequence is exited. This often occurs prior
356  * to receiving the status byte, in which case the driver does a
357  * status phase interrupt and gets the status byte on its own.
358  * While such a command can then be "resumed" (ie restarted to
359  * finish up as a LEVEL2 command), the LUN register will NOT be
360  * a valid status byte at the command's conclusion, and we must
361  * use the byte obtained during the earlier interrupt. Here, we
362  * preset SCp.Status to an illegal value (0xff) so that when
363  * this command finally completes, we can tell where the actual
364  * status byte is stored.
365  */
366 
367 	scsi_pointer->Status = ILLEGAL_STATUS_BYTE;
368 
369 	/*
370 	 * Add the cmd to the end of 'input_Q'. Note that REQUEST SENSE
371 	 * commands are added to the head of the queue so that the desired
372 	 * sense data is not lost before REQUEST_SENSE executes.
373 	 */
374 
375 	spin_lock_irq(&hostdata->lock);
376 
377 	if (!(hostdata->input_Q) || (cmd->cmnd[0] == REQUEST_SENSE)) {
378 		cmd->host_scribble = (uchar *) hostdata->input_Q;
379 		hostdata->input_Q = cmd;
380 	} else {		/* find the end of the queue */
381 		for (tmp = (struct scsi_cmnd *) hostdata->input_Q;
382 		     tmp->host_scribble;
383 		     tmp = (struct scsi_cmnd *) tmp->host_scribble) ;
384 		tmp->host_scribble = (uchar *) cmd;
385 	}
386 
387 /* We know that there's at least one command in 'input_Q' now.
388  * Go see if any of them are runnable!
389  */
390 
391 	wd33c93_execute(cmd->device->host);
392 
393 	DB(DB_QUEUE_COMMAND, printk(")Q "))
394 
395 	spin_unlock_irq(&hostdata->lock);
396 	return 0;
397 }
398 
DEF_SCSI_QCMD(wd33c93_queuecommand)399 DEF_SCSI_QCMD(wd33c93_queuecommand)
400 
401 /*
402  * This routine attempts to start a scsi command. If the host_card is
403  * already connected, we give up immediately. Otherwise, look through
404  * the input_Q, using the first command we find that's intended
405  * for a currently non-busy target/lun.
406  *
407  * wd33c93_execute() is always called with interrupts disabled or from
408  * the wd33c93_intr itself, which means that a wd33c93 interrupt
409  * cannot occur while we are in here.
410  */
411 static void
412 wd33c93_execute(struct Scsi_Host *instance)
413 {
414 	struct scsi_pointer *scsi_pointer;
415 	struct WD33C93_hostdata *hostdata =
416 	    (struct WD33C93_hostdata *) instance->hostdata;
417 	const wd33c93_regs regs = hostdata->regs;
418 	struct scsi_cmnd *cmd, *prev;
419 
420 	DB(DB_EXECUTE, printk("EX("))
421 	if (hostdata->selecting || hostdata->connected) {
422 		DB(DB_EXECUTE, printk(")EX-0 "))
423 		return;
424 	}
425 
426 	/*
427 	 * Search through the input_Q for a command destined
428 	 * for an idle target/lun.
429 	 */
430 
431 	cmd = (struct scsi_cmnd *) hostdata->input_Q;
432 	prev = NULL;
433 	while (cmd) {
434 		if (!(hostdata->busy[cmd->device->id] &
435 		      (1 << (cmd->device->lun & 0xff))))
436 			break;
437 		prev = cmd;
438 		cmd = (struct scsi_cmnd *) cmd->host_scribble;
439 	}
440 
441 	/* quit if queue empty or all possible targets are busy */
442 
443 	if (!cmd) {
444 		DB(DB_EXECUTE, printk(")EX-1 "))
445 		return;
446 	}
447 
448 	/*  remove command from queue */
449 
450 	if (prev)
451 		prev->host_scribble = cmd->host_scribble;
452 	else
453 		hostdata->input_Q = (struct scsi_cmnd *) cmd->host_scribble;
454 
455 #ifdef PROC_STATISTICS
456 	hostdata->cmd_cnt[cmd->device->id]++;
457 #endif
458 
459 	/*
460 	 * Start the selection process
461 	 */
462 
463 	if (cmd->sc_data_direction == DMA_TO_DEVICE)
464 		write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
465 	else
466 		write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id | DSTID_DPD);
467 
468 /* Now we need to figure out whether or not this command is a good
469  * candidate for disconnect/reselect. We guess to the best of our
470  * ability, based on a set of hierarchical rules. When several
471  * devices are operating simultaneously, disconnects are usually
472  * an advantage. In a single device system, or if only 1 device
473  * is being accessed, transfers usually go faster if disconnects
474  * are not allowed:
475  *
476  * + Commands should NEVER disconnect if hostdata->disconnect =
477  *   DIS_NEVER (this holds for tape drives also), and ALWAYS
478  *   disconnect if hostdata->disconnect = DIS_ALWAYS.
479  * + Tape drive commands should always be allowed to disconnect.
480  * + Disconnect should be allowed if disconnected_Q isn't empty.
481  * + Commands should NOT disconnect if input_Q is empty.
482  * + Disconnect should be allowed if there are commands in input_Q
483  *   for a different target/lun. In this case, the other commands
484  *   should be made disconnect-able, if not already.
485  *
486  * I know, I know - this code would flunk me out of any
487  * "C Programming 101" class ever offered. But it's easy
488  * to change around and experiment with for now.
489  */
490 
491 	scsi_pointer = WD33C93_scsi_pointer(cmd);
492 	scsi_pointer->phase = 0;	/* assume no disconnect */
493 	if (hostdata->disconnect == DIS_NEVER)
494 		goto no;
495 	if (hostdata->disconnect == DIS_ALWAYS)
496 		goto yes;
497 	if (cmd->device->type == 1)	/* tape drive? */
498 		goto yes;
499 	if (hostdata->disconnected_Q)	/* other commands disconnected? */
500 		goto yes;
501 	if (!(hostdata->input_Q))	/* input_Q empty? */
502 		goto no;
503 	for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
504 	     prev = (struct scsi_cmnd *) prev->host_scribble) {
505 		if ((prev->device->id != cmd->device->id) ||
506 		    (prev->device->lun != cmd->device->lun)) {
507 			for (prev = (struct scsi_cmnd *) hostdata->input_Q; prev;
508 			     prev = (struct scsi_cmnd *) prev->host_scribble)
509 				WD33C93_scsi_pointer(prev)->phase = 1;
510 			goto yes;
511 		}
512 	}
513 
514 	goto no;
515 
516  yes:
517 	scsi_pointer->phase = 1;
518 
519 #ifdef PROC_STATISTICS
520 	hostdata->disc_allowed_cnt[cmd->device->id]++;
521 #endif
522 
523  no:
524 
525 	write_wd33c93(regs, WD_SOURCE_ID, scsi_pointer->phase ? SRCID_ER : 0);
526 
527 	write_wd33c93(regs, WD_TARGET_LUN, (u8)cmd->device->lun);
528 	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
529 		      hostdata->sync_xfer[cmd->device->id]);
530 	hostdata->busy[cmd->device->id] |= (1 << (cmd->device->lun & 0xFF));
531 
532 	if ((hostdata->level2 == L2_NONE) ||
533 	    (hostdata->sync_stat[cmd->device->id] == SS_UNSET)) {
534 
535 		/*
536 		 * Do a 'Select-With-ATN' command. This will end with
537 		 * one of the following interrupts:
538 		 *    CSR_RESEL_AM:  failure - can try again later.
539 		 *    CSR_TIMEOUT:   failure - give up.
540 		 *    CSR_SELECT:    success - proceed.
541 		 */
542 
543 		hostdata->selecting = cmd;
544 
545 /* Every target has its own synchronous transfer setting, kept in the
546  * sync_xfer array, and a corresponding status byte in sync_stat[].
547  * Each target's sync_stat[] entry is initialized to SX_UNSET, and its
548  * sync_xfer[] entry is initialized to the default/safe value. SS_UNSET
549  * means that the parameters are undetermined as yet, and that we
550  * need to send an SDTR message to this device after selection is
551  * complete: We set SS_FIRST to tell the interrupt routine to do so.
552  * If we've been asked not to try synchronous transfers on this
553  * target (and _all_ luns within it), we'll still send the SDTR message
554  * later, but at that time we'll negotiate for async by specifying a
555  * sync fifo depth of 0.
556  */
557 		if (hostdata->sync_stat[cmd->device->id] == SS_UNSET)
558 			hostdata->sync_stat[cmd->device->id] = SS_FIRST;
559 		hostdata->state = S_SELECTING;
560 		write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
561 		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN);
562 	} else {
563 
564 		/*
565 		 * Do a 'Select-With-ATN-Xfer' command. This will end with
566 		 * one of the following interrupts:
567 		 *    CSR_RESEL_AM:  failure - can try again later.
568 		 *    CSR_TIMEOUT:   failure - give up.
569 		 *    anything else: success - proceed.
570 		 */
571 
572 		hostdata->connected = cmd;
573 		write_wd33c93(regs, WD_COMMAND_PHASE, 0);
574 
575 		/* copy command_descriptor_block into WD chip
576 		 * (take advantage of auto-incrementing)
577 		 */
578 
579 		write_wd33c93_cdb(regs, cmd->cmd_len, cmd->cmnd);
580 
581 		/* The wd33c93 only knows about Group 0, 1, and 5 commands when
582 		 * it's doing a 'select-and-transfer'. To be safe, we write the
583 		 * size of the CDB into the OWN_ID register for every case. This
584 		 * way there won't be problems with vendor-unique, audio, etc.
585 		 */
586 
587 		write_wd33c93(regs, WD_OWN_ID, cmd->cmd_len);
588 
589 		/* When doing a non-disconnect command with DMA, we can save
590 		 * ourselves a DATA phase interrupt later by setting everything
591 		 * up ahead of time.
592 		 */
593 
594 		if (scsi_pointer->phase == 0 && hostdata->no_dma == 0) {
595 			if (hostdata->dma_setup(cmd,
596 			    (cmd->sc_data_direction == DMA_TO_DEVICE) ?
597 			     DATA_OUT_DIR : DATA_IN_DIR))
598 				write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
599 			else {
600 				write_wd33c93_count(regs,
601 						scsi_pointer->this_residual);
602 				write_wd33c93(regs, WD_CONTROL,
603 					      CTRL_IDI | CTRL_EDI | hostdata->dma_mode);
604 				hostdata->dma = D_DMA_RUNNING;
605 			}
606 		} else
607 			write_wd33c93_count(regs, 0);	/* guarantee a DATA_PHASE interrupt */
608 
609 		hostdata->state = S_RUNNING_LEVEL2;
610 		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
611 	}
612 
613 	/*
614 	 * Since the SCSI bus can handle only 1 connection at a time,
615 	 * we get out of here now. If the selection fails, or when
616 	 * the command disconnects, we'll come back to this routine
617 	 * to search the input_Q again...
618 	 */
619 
620 	DB(DB_EXECUTE,
621 	   printk("%s)EX-2 ", scsi_pointer->phase ? "d:" : ""))
622 }
623 
624 static void
transfer_pio(const wd33c93_regs regs,uchar * buf,int cnt,int data_in_dir,struct WD33C93_hostdata * hostdata)625 transfer_pio(const wd33c93_regs regs, uchar * buf, int cnt,
626 	     int data_in_dir, struct WD33C93_hostdata *hostdata)
627 {
628 	uchar asr;
629 
630 	DB(DB_TRANSFER,
631 	   printk("(%p,%d,%s:", buf, cnt, data_in_dir ? "in" : "out"))
632 
633 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
634 	write_wd33c93_count(regs, cnt);
635 	write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
636 	if (data_in_dir) {
637 		do {
638 			asr = read_aux_stat(regs);
639 			if (asr & ASR_DBR)
640 				*buf++ = read_wd33c93(regs, WD_DATA);
641 		} while (!(asr & ASR_INT));
642 	} else {
643 		do {
644 			asr = read_aux_stat(regs);
645 			if (asr & ASR_DBR)
646 				write_wd33c93(regs, WD_DATA, *buf++);
647 		} while (!(asr & ASR_INT));
648 	}
649 
650 	/* Note: we are returning with the interrupt UN-cleared.
651 	 * Since (presumably) an entire I/O operation has
652 	 * completed, the bus phase is probably different, and
653 	 * the interrupt routine will discover this when it
654 	 * responds to the uncleared int.
655 	 */
656 
657 }
658 
659 static void
transfer_bytes(const wd33c93_regs regs,struct scsi_cmnd * cmd,int data_in_dir)660 transfer_bytes(const wd33c93_regs regs, struct scsi_cmnd *cmd,
661 		int data_in_dir)
662 {
663 	struct scsi_pointer *scsi_pointer = WD33C93_scsi_pointer(cmd);
664 	struct WD33C93_hostdata *hostdata;
665 	unsigned long length;
666 
667 	hostdata = (struct WD33C93_hostdata *) cmd->device->host->hostdata;
668 
669 /* Normally, you'd expect 'this_residual' to be non-zero here.
670  * In a series of scatter-gather transfers, however, this
671  * routine will usually be called with 'this_residual' equal
672  * to 0 and 'buffers_residual' non-zero. This means that a
673  * previous transfer completed, clearing 'this_residual', and
674  * now we need to setup the next scatter-gather buffer as the
675  * source or destination for THIS transfer.
676  */
677 	if (!scsi_pointer->this_residual && scsi_pointer->buffers_residual) {
678 		scsi_pointer->buffer = sg_next(scsi_pointer->buffer);
679 		--scsi_pointer->buffers_residual;
680 		scsi_pointer->this_residual = scsi_pointer->buffer->length;
681 		scsi_pointer->ptr = sg_virt(scsi_pointer->buffer);
682 	}
683 	if (!scsi_pointer->this_residual) /* avoid bogus setups */
684 		return;
685 
686 	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
687 		      hostdata->sync_xfer[cmd->device->id]);
688 
689 /* 'hostdata->no_dma' is TRUE if we don't even want to try DMA.
690  * Update 'this_residual' and 'ptr' after 'transfer_pio()' returns.
691  */
692 
693 	if (hostdata->no_dma || hostdata->dma_setup(cmd, data_in_dir)) {
694 #ifdef PROC_STATISTICS
695 		hostdata->pio_cnt++;
696 #endif
697 		transfer_pio(regs, (uchar *) scsi_pointer->ptr,
698 			     scsi_pointer->this_residual, data_in_dir,
699 			     hostdata);
700 		length = scsi_pointer->this_residual;
701 		scsi_pointer->this_residual = read_wd33c93_count(regs);
702 		scsi_pointer->ptr += length - scsi_pointer->this_residual;
703 	}
704 
705 /* We are able to do DMA (in fact, the Amiga hardware is
706  * already going!), so start up the wd33c93 in DMA mode.
707  * We set 'hostdata->dma' = D_DMA_RUNNING so that when the
708  * transfer completes and causes an interrupt, we're
709  * reminded to tell the Amiga to shut down its end. We'll
710  * postpone the updating of 'this_residual' and 'ptr'
711  * until then.
712  */
713 
714 	else {
715 #ifdef PROC_STATISTICS
716 		hostdata->dma_cnt++;
717 #endif
718 		write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | hostdata->dma_mode);
719 		write_wd33c93_count(regs, scsi_pointer->this_residual);
720 
721 		if ((hostdata->level2 >= L2_DATA) ||
722 		    (hostdata->level2 == L2_BASIC && scsi_pointer->phase == 0)) {
723 			write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
724 			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
725 			hostdata->state = S_RUNNING_LEVEL2;
726 		} else
727 			write_wd33c93_cmd(regs, WD_CMD_TRANS_INFO);
728 
729 		hostdata->dma = D_DMA_RUNNING;
730 	}
731 }
732 
733 void
wd33c93_intr(struct Scsi_Host * instance)734 wd33c93_intr(struct Scsi_Host *instance)
735 {
736 	struct scsi_pointer *scsi_pointer;
737 	struct WD33C93_hostdata *hostdata =
738 	    (struct WD33C93_hostdata *) instance->hostdata;
739 	const wd33c93_regs regs = hostdata->regs;
740 	struct scsi_cmnd *patch, *cmd;
741 	uchar asr, sr, phs, id, lun, *ucp, msg;
742 	unsigned long length, flags;
743 
744 	asr = read_aux_stat(regs);
745 	if (!(asr & ASR_INT) || (asr & ASR_BSY))
746 		return;
747 
748 	spin_lock_irqsave(&hostdata->lock, flags);
749 
750 #ifdef PROC_STATISTICS
751 	hostdata->int_cnt++;
752 #endif
753 
754 	cmd = (struct scsi_cmnd *) hostdata->connected;	/* assume we're connected */
755 	scsi_pointer = WD33C93_scsi_pointer(cmd);
756 	sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear the interrupt */
757 	phs = read_wd33c93(regs, WD_COMMAND_PHASE);
758 
759 	DB(DB_INTR, printk("{%02x:%02x-", asr, sr))
760 
761 /* After starting a DMA transfer, the next interrupt
762  * is guaranteed to be in response to completion of
763  * the transfer. Since the Amiga DMA hardware runs in
764  * in an open-ended fashion, it needs to be told when
765  * to stop; do that here if D_DMA_RUNNING is true.
766  * Also, we have to update 'this_residual' and 'ptr'
767  * based on the contents of the TRANSFER_COUNT register,
768  * in case the device decided to do an intermediate
769  * disconnect (a device may do this if it has to do a
770  * seek, or just to be nice and let other devices have
771  * some bus time during long transfers). After doing
772  * whatever is needed, we go on and service the WD3393
773  * interrupt normally.
774  */
775 	    if (hostdata->dma == D_DMA_RUNNING) {
776 		DB(DB_TRANSFER,
777 		   printk("[%p/%d:", scsi_pointer->ptr, scsi_pointer->this_residual))
778 		    hostdata->dma_stop(cmd->device->host, cmd, 1);
779 		hostdata->dma = D_DMA_OFF;
780 		length = scsi_pointer->this_residual;
781 		scsi_pointer->this_residual = read_wd33c93_count(regs);
782 		scsi_pointer->ptr += length - scsi_pointer->this_residual;
783 		DB(DB_TRANSFER,
784 		   printk("%p/%d]", scsi_pointer->ptr, scsi_pointer->this_residual))
785 	}
786 
787 /* Respond to the specific WD3393 interrupt - there are quite a few! */
788 	switch (sr) {
789 	case CSR_TIMEOUT:
790 		DB(DB_INTR, printk("TIMEOUT"))
791 
792 		    if (hostdata->state == S_RUNNING_LEVEL2)
793 			hostdata->connected = NULL;
794 		else {
795 			cmd = (struct scsi_cmnd *) hostdata->selecting;	/* get a valid cmd */
796 			hostdata->selecting = NULL;
797 		}
798 
799 		cmd->result = DID_NO_CONNECT << 16;
800 		hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
801 		hostdata->state = S_UNCONNECTED;
802 		scsi_done(cmd);
803 
804 		/* From esp.c:
805 		 * There is a window of time within the scsi_done() path
806 		 * of execution where interrupts are turned back on full
807 		 * blast and left that way.  During that time we could
808 		 * reconnect to a disconnected command, then we'd bomb
809 		 * out below.  We could also end up executing two commands
810 		 * at _once_.  ...just so you know why the restore_flags()
811 		 * is here...
812 		 */
813 
814 		spin_unlock_irqrestore(&hostdata->lock, flags);
815 
816 /* We are not connected to a target - check to see if there
817  * are commands waiting to be executed.
818  */
819 
820 		wd33c93_execute(instance);
821 		break;
822 
823 /* Note: this interrupt should not occur in a LEVEL2 command */
824 
825 	case CSR_SELECT:
826 		DB(DB_INTR, printk("SELECT"))
827 		    hostdata->connected = cmd =
828 		    (struct scsi_cmnd *) hostdata->selecting;
829 		hostdata->selecting = NULL;
830 
831 		/* construct an IDENTIFY message with correct disconnect bit */
832 
833 		hostdata->outgoing_msg[0] = IDENTIFY(0, cmd->device->lun);
834 		if (WD33C93_scsi_pointer(cmd)->phase)
835 			hostdata->outgoing_msg[0] |= 0x40;
836 
837 		if (hostdata->sync_stat[cmd->device->id] == SS_FIRST) {
838 
839 			hostdata->sync_stat[cmd->device->id] = SS_WAITING;
840 
841 /* Tack on a 2nd message to ask about synchronous transfers. If we've
842  * been asked to do only asynchronous transfers on this device, we
843  * request a fifo depth of 0, which is equivalent to async - should
844  * solve the problems some people have had with GVP's Guru ROM.
845  */
846 
847 			hostdata->outgoing_msg[1] = EXTENDED_MESSAGE;
848 			hostdata->outgoing_msg[2] = 3;
849 			hostdata->outgoing_msg[3] = EXTENDED_SDTR;
850 			if (hostdata->no_sync & (1 << cmd->device->id)) {
851 				calc_sync_msg(hostdata->default_sx_per, 0,
852 						0, hostdata->outgoing_msg + 4);
853 			} else {
854 				calc_sync_msg(optimum_sx_per(hostdata),
855 						OPTIMUM_SX_OFF,
856 						hostdata->fast,
857 						hostdata->outgoing_msg + 4);
858 			}
859 			hostdata->outgoing_len = 6;
860 #ifdef SYNC_DEBUG
861 			ucp = hostdata->outgoing_msg + 1;
862 			printk(" sending SDTR %02x03%02x%02x%02x ",
863 				ucp[0], ucp[2], ucp[3], ucp[4]);
864 #endif
865 		} else
866 			hostdata->outgoing_len = 1;
867 
868 		hostdata->state = S_CONNECTED;
869 		spin_unlock_irqrestore(&hostdata->lock, flags);
870 		break;
871 
872 	case CSR_XFER_DONE | PHS_DATA_IN:
873 	case CSR_UNEXP | PHS_DATA_IN:
874 	case CSR_SRV_REQ | PHS_DATA_IN:
875 		DB(DB_INTR,
876 		   printk("IN-%d.%d", scsi_pointer->this_residual,
877 			  scsi_pointer->buffers_residual))
878 		    transfer_bytes(regs, cmd, DATA_IN_DIR);
879 		if (hostdata->state != S_RUNNING_LEVEL2)
880 			hostdata->state = S_CONNECTED;
881 		spin_unlock_irqrestore(&hostdata->lock, flags);
882 		break;
883 
884 	case CSR_XFER_DONE | PHS_DATA_OUT:
885 	case CSR_UNEXP | PHS_DATA_OUT:
886 	case CSR_SRV_REQ | PHS_DATA_OUT:
887 		DB(DB_INTR,
888 		   printk("OUT-%d.%d", scsi_pointer->this_residual,
889 			  scsi_pointer->buffers_residual))
890 		    transfer_bytes(regs, cmd, DATA_OUT_DIR);
891 		if (hostdata->state != S_RUNNING_LEVEL2)
892 			hostdata->state = S_CONNECTED;
893 		spin_unlock_irqrestore(&hostdata->lock, flags);
894 		break;
895 
896 /* Note: this interrupt should not occur in a LEVEL2 command */
897 
898 	case CSR_XFER_DONE | PHS_COMMAND:
899 	case CSR_UNEXP | PHS_COMMAND:
900 	case CSR_SRV_REQ | PHS_COMMAND:
901 		DB(DB_INTR, printk("CMND-%02x", cmd->cmnd[0]))
902 		    transfer_pio(regs, cmd->cmnd, cmd->cmd_len, DATA_OUT_DIR,
903 				 hostdata);
904 		hostdata->state = S_CONNECTED;
905 		spin_unlock_irqrestore(&hostdata->lock, flags);
906 		break;
907 
908 	case CSR_XFER_DONE | PHS_STATUS:
909 	case CSR_UNEXP | PHS_STATUS:
910 	case CSR_SRV_REQ | PHS_STATUS:
911 		DB(DB_INTR, printk("STATUS="))
912 		scsi_pointer->Status = read_1_byte(regs);
913 		DB(DB_INTR, printk("%02x", scsi_pointer->Status))
914 		    if (hostdata->level2 >= L2_BASIC) {
915 			sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear interrupt */
916 			udelay(7);
917 			hostdata->state = S_RUNNING_LEVEL2;
918 			write_wd33c93(regs, WD_COMMAND_PHASE, 0x50);
919 			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
920 		} else {
921 			hostdata->state = S_CONNECTED;
922 		}
923 		spin_unlock_irqrestore(&hostdata->lock, flags);
924 		break;
925 
926 	case CSR_XFER_DONE | PHS_MESS_IN:
927 	case CSR_UNEXP | PHS_MESS_IN:
928 	case CSR_SRV_REQ | PHS_MESS_IN:
929 		DB(DB_INTR, printk("MSG_IN="))
930 
931 		msg = read_1_byte(regs);
932 		sr = read_wd33c93(regs, WD_SCSI_STATUS);	/* clear interrupt */
933 		udelay(7);
934 
935 		hostdata->incoming_msg[hostdata->incoming_ptr] = msg;
936 		if (hostdata->incoming_msg[0] == EXTENDED_MESSAGE)
937 			msg = EXTENDED_MESSAGE;
938 		else
939 			hostdata->incoming_ptr = 0;
940 
941 		scsi_pointer->Message = msg;
942 		switch (msg) {
943 
944 		case COMMAND_COMPLETE:
945 			DB(DB_INTR, printk("CCMP"))
946 			    write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
947 			hostdata->state = S_PRE_CMP_DISC;
948 			break;
949 
950 		case SAVE_POINTERS:
951 			DB(DB_INTR, printk("SDP"))
952 			    write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
953 			hostdata->state = S_CONNECTED;
954 			break;
955 
956 		case RESTORE_POINTERS:
957 			DB(DB_INTR, printk("RDP"))
958 			    if (hostdata->level2 >= L2_BASIC) {
959 				write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
960 				write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
961 				hostdata->state = S_RUNNING_LEVEL2;
962 			} else {
963 				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
964 				hostdata->state = S_CONNECTED;
965 			}
966 			break;
967 
968 		case DISCONNECT:
969 			DB(DB_INTR, printk("DIS"))
970 			    cmd->device->disconnect = 1;
971 			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
972 			hostdata->state = S_PRE_TMP_DISC;
973 			break;
974 
975 		case MESSAGE_REJECT:
976 			DB(DB_INTR, printk("REJ"))
977 #ifdef SYNC_DEBUG
978 			    printk("-REJ-");
979 #endif
980 			if (hostdata->sync_stat[cmd->device->id] == SS_WAITING) {
981 				hostdata->sync_stat[cmd->device->id] = SS_SET;
982 				/* we want default_sx_per, not DEFAULT_SX_PER */
983 				hostdata->sync_xfer[cmd->device->id] =
984 					calc_sync_xfer(hostdata->default_sx_per
985 						/ 4, 0, 0, hostdata->sx_table);
986 			}
987 			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
988 			hostdata->state = S_CONNECTED;
989 			break;
990 
991 		case EXTENDED_MESSAGE:
992 			DB(DB_INTR, printk("EXT"))
993 
994 			    ucp = hostdata->incoming_msg;
995 
996 #ifdef SYNC_DEBUG
997 			printk("%02x", ucp[hostdata->incoming_ptr]);
998 #endif
999 			/* Is this the last byte of the extended message? */
1000 
1001 			if ((hostdata->incoming_ptr >= 2) &&
1002 			    (hostdata->incoming_ptr == (ucp[1] + 1))) {
1003 
1004 				switch (ucp[2]) {	/* what's the EXTENDED code? */
1005 				case EXTENDED_SDTR:
1006 					/* default to default async period */
1007 					id = calc_sync_xfer(hostdata->
1008 							default_sx_per / 4, 0,
1009 							0, hostdata->sx_table);
1010 					if (hostdata->sync_stat[cmd->device->id] !=
1011 					    SS_WAITING) {
1012 
1013 /* A device has sent an unsolicited SDTR message; rather than go
1014  * through the effort of decoding it and then figuring out what
1015  * our reply should be, we're just gonna say that we have a
1016  * synchronous fifo depth of 0. This will result in asynchronous
1017  * transfers - not ideal but so much easier.
1018  * Actually, this is OK because it assures us that if we don't
1019  * specifically ask for sync transfers, we won't do any.
1020  */
1021 
1022 						write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1023 						hostdata->outgoing_msg[0] =
1024 						    EXTENDED_MESSAGE;
1025 						hostdata->outgoing_msg[1] = 3;
1026 						hostdata->outgoing_msg[2] =
1027 						    EXTENDED_SDTR;
1028 						calc_sync_msg(hostdata->
1029 							default_sx_per, 0,
1030 							0, hostdata->outgoing_msg + 3);
1031 						hostdata->outgoing_len = 5;
1032 					} else {
1033 						if (ucp[4]) /* well, sync transfer */
1034 							id = calc_sync_xfer(ucp[3], ucp[4],
1035 									hostdata->fast,
1036 									hostdata->sx_table);
1037 						else if (ucp[3]) /* very unlikely... */
1038 							id = calc_sync_xfer(ucp[3], ucp[4],
1039 									0, hostdata->sx_table);
1040 					}
1041 					hostdata->sync_xfer[cmd->device->id] = id;
1042 #ifdef SYNC_DEBUG
1043 					printk(" sync_xfer=%02x\n",
1044 					       hostdata->sync_xfer[cmd->device->id]);
1045 #endif
1046 					hostdata->sync_stat[cmd->device->id] =
1047 					    SS_SET;
1048 					write_wd33c93_cmd(regs,
1049 							  WD_CMD_NEGATE_ACK);
1050 					hostdata->state = S_CONNECTED;
1051 					break;
1052 				case EXTENDED_WDTR:
1053 					write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1054 					printk("sending WDTR ");
1055 					hostdata->outgoing_msg[0] =
1056 					    EXTENDED_MESSAGE;
1057 					hostdata->outgoing_msg[1] = 2;
1058 					hostdata->outgoing_msg[2] =
1059 					    EXTENDED_WDTR;
1060 					hostdata->outgoing_msg[3] = 0;	/* 8 bit transfer width */
1061 					hostdata->outgoing_len = 4;
1062 					write_wd33c93_cmd(regs,
1063 							  WD_CMD_NEGATE_ACK);
1064 					hostdata->state = S_CONNECTED;
1065 					break;
1066 				default:
1067 					write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1068 					printk
1069 					    ("Rejecting Unknown Extended Message(%02x). ",
1070 					     ucp[2]);
1071 					hostdata->outgoing_msg[0] =
1072 					    MESSAGE_REJECT;
1073 					hostdata->outgoing_len = 1;
1074 					write_wd33c93_cmd(regs,
1075 							  WD_CMD_NEGATE_ACK);
1076 					hostdata->state = S_CONNECTED;
1077 					break;
1078 				}
1079 				hostdata->incoming_ptr = 0;
1080 			}
1081 
1082 			/* We need to read more MESS_IN bytes for the extended message */
1083 
1084 			else {
1085 				hostdata->incoming_ptr++;
1086 				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1087 				hostdata->state = S_CONNECTED;
1088 			}
1089 			break;
1090 
1091 		default:
1092 			printk("Rejecting Unknown Message(%02x) ", msg);
1093 			write_wd33c93_cmd(regs, WD_CMD_ASSERT_ATN);	/* want MESS_OUT */
1094 			hostdata->outgoing_msg[0] = MESSAGE_REJECT;
1095 			hostdata->outgoing_len = 1;
1096 			write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1097 			hostdata->state = S_CONNECTED;
1098 		}
1099 		spin_unlock_irqrestore(&hostdata->lock, flags);
1100 		break;
1101 
1102 /* Note: this interrupt will occur only after a LEVEL2 command */
1103 
1104 	case CSR_SEL_XFER_DONE:
1105 
1106 /* Make sure that reselection is enabled at this point - it may
1107  * have been turned off for the command that just completed.
1108  */
1109 
1110 		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
1111 		if (phs == 0x60) {
1112 			DB(DB_INTR, printk("SX-DONE"))
1113 			    scsi_pointer->Message = COMMAND_COMPLETE;
1114 			lun = read_wd33c93(regs, WD_TARGET_LUN);
1115 			DB(DB_INTR, printk(":%d.%d", scsi_pointer->Status, lun))
1116 			    hostdata->connected = NULL;
1117 			hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1118 			hostdata->state = S_UNCONNECTED;
1119 			if (scsi_pointer->Status == ILLEGAL_STATUS_BYTE)
1120 				scsi_pointer->Status = lun;
1121 			if (cmd->cmnd[0] == REQUEST_SENSE
1122 			    && scsi_pointer->Status != SAM_STAT_GOOD) {
1123 				set_host_byte(cmd, DID_ERROR);
1124 			} else {
1125 				set_host_byte(cmd, DID_OK);
1126 				scsi_msg_to_host_byte(cmd, scsi_pointer->Message);
1127 				set_status_byte(cmd, scsi_pointer->Status);
1128 			}
1129 			scsi_done(cmd);
1130 
1131 /* We are no longer  connected to a target - check to see if
1132  * there are commands waiting to be executed.
1133  */
1134 			spin_unlock_irqrestore(&hostdata->lock, flags);
1135 			wd33c93_execute(instance);
1136 		} else {
1137 			printk
1138 			    ("%02x:%02x:%02x: Unknown SEL_XFER_DONE phase!!---",
1139 			     asr, sr, phs);
1140 			spin_unlock_irqrestore(&hostdata->lock, flags);
1141 		}
1142 		break;
1143 
1144 /* Note: this interrupt will occur only after a LEVEL2 command */
1145 
1146 	case CSR_SDP:
1147 		DB(DB_INTR, printk("SDP"))
1148 		    hostdata->state = S_RUNNING_LEVEL2;
1149 		write_wd33c93(regs, WD_COMMAND_PHASE, 0x41);
1150 		write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
1151 		spin_unlock_irqrestore(&hostdata->lock, flags);
1152 		break;
1153 
1154 	case CSR_XFER_DONE | PHS_MESS_OUT:
1155 	case CSR_UNEXP | PHS_MESS_OUT:
1156 	case CSR_SRV_REQ | PHS_MESS_OUT:
1157 		DB(DB_INTR, printk("MSG_OUT="))
1158 
1159 /* To get here, we've probably requested MESSAGE_OUT and have
1160  * already put the correct bytes in outgoing_msg[] and filled
1161  * in outgoing_len. We simply send them out to the SCSI bus.
1162  * Sometimes we get MESSAGE_OUT phase when we're not expecting
1163  * it - like when our SDTR message is rejected by a target. Some
1164  * targets send the REJECT before receiving all of the extended
1165  * message, and then seem to go back to MESSAGE_OUT for a byte
1166  * or two. Not sure why, or if I'm doing something wrong to
1167  * cause this to happen. Regardless, it seems that sending
1168  * NOP messages in these situations results in no harm and
1169  * makes everyone happy.
1170  */
1171 		    if (hostdata->outgoing_len == 0) {
1172 			hostdata->outgoing_len = 1;
1173 			hostdata->outgoing_msg[0] = NOP;
1174 		}
1175 		transfer_pio(regs, hostdata->outgoing_msg,
1176 			     hostdata->outgoing_len, DATA_OUT_DIR, hostdata);
1177 		DB(DB_INTR, printk("%02x", hostdata->outgoing_msg[0]))
1178 		    hostdata->outgoing_len = 0;
1179 		hostdata->state = S_CONNECTED;
1180 		spin_unlock_irqrestore(&hostdata->lock, flags);
1181 		break;
1182 
1183 	case CSR_UNEXP_DISC:
1184 
1185 /* I think I've seen this after a request-sense that was in response
1186  * to an error condition, but not sure. We certainly need to do
1187  * something when we get this interrupt - the question is 'what?'.
1188  * Let's think positively, and assume some command has finished
1189  * in a legal manner (like a command that provokes a request-sense),
1190  * so we treat it as a normal command-complete-disconnect.
1191  */
1192 
1193 /* Make sure that reselection is enabled at this point - it may
1194  * have been turned off for the command that just completed.
1195  */
1196 
1197 		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
1198 		if (cmd == NULL) {
1199 			printk(" - Already disconnected! ");
1200 			hostdata->state = S_UNCONNECTED;
1201 			spin_unlock_irqrestore(&hostdata->lock, flags);
1202 			return;
1203 		}
1204 		DB(DB_INTR, printk("UNEXP_DISC"))
1205 		    hostdata->connected = NULL;
1206 		hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1207 		hostdata->state = S_UNCONNECTED;
1208 		if (cmd->cmnd[0] == REQUEST_SENSE &&
1209 		    scsi_pointer->Status != SAM_STAT_GOOD) {
1210 			set_host_byte(cmd, DID_ERROR);
1211 		} else {
1212 			set_host_byte(cmd, DID_OK);
1213 			scsi_msg_to_host_byte(cmd, scsi_pointer->Message);
1214 			set_status_byte(cmd, scsi_pointer->Status);
1215 		}
1216 		scsi_done(cmd);
1217 
1218 /* We are no longer connected to a target - check to see if
1219  * there are commands waiting to be executed.
1220  */
1221 		/* look above for comments on scsi_done() */
1222 		spin_unlock_irqrestore(&hostdata->lock, flags);
1223 		wd33c93_execute(instance);
1224 		break;
1225 
1226 	case CSR_DISC:
1227 
1228 /* Make sure that reselection is enabled at this point - it may
1229  * have been turned off for the command that just completed.
1230  */
1231 
1232 		write_wd33c93(regs, WD_SOURCE_ID, SRCID_ER);
1233 		DB(DB_INTR, printk("DISC"))
1234 		    if (cmd == NULL) {
1235 			printk(" - Already disconnected! ");
1236 			hostdata->state = S_UNCONNECTED;
1237 		}
1238 		switch (hostdata->state) {
1239 		case S_PRE_CMP_DISC:
1240 			hostdata->connected = NULL;
1241 			hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1242 			hostdata->state = S_UNCONNECTED;
1243 			DB(DB_INTR, printk(":%d", scsi_pointer->Status))
1244 			if (cmd->cmnd[0] == REQUEST_SENSE
1245 			    && scsi_pointer->Status != SAM_STAT_GOOD) {
1246 				set_host_byte(cmd, DID_ERROR);
1247 			} else {
1248 				set_host_byte(cmd, DID_OK);
1249 				scsi_msg_to_host_byte(cmd, scsi_pointer->Message);
1250 				set_status_byte(cmd, scsi_pointer->Status);
1251 			}
1252 			scsi_done(cmd);
1253 			break;
1254 		case S_PRE_TMP_DISC:
1255 		case S_RUNNING_LEVEL2:
1256 			cmd->host_scribble = (uchar *) hostdata->disconnected_Q;
1257 			hostdata->disconnected_Q = cmd;
1258 			hostdata->connected = NULL;
1259 			hostdata->state = S_UNCONNECTED;
1260 
1261 #ifdef PROC_STATISTICS
1262 			hostdata->disc_done_cnt[cmd->device->id]++;
1263 #endif
1264 
1265 			break;
1266 		default:
1267 			printk("*** Unexpected DISCONNECT interrupt! ***");
1268 			hostdata->state = S_UNCONNECTED;
1269 		}
1270 
1271 /* We are no longer connected to a target - check to see if
1272  * there are commands waiting to be executed.
1273  */
1274 		spin_unlock_irqrestore(&hostdata->lock, flags);
1275 		wd33c93_execute(instance);
1276 		break;
1277 
1278 	case CSR_RESEL_AM:
1279 	case CSR_RESEL:
1280 		DB(DB_INTR, printk("RESEL%s", sr == CSR_RESEL_AM ? "_AM" : ""))
1281 
1282 		    /* Old chips (pre -A ???) don't have advanced features and will
1283 		     * generate CSR_RESEL.  In that case we have to extract the LUN the
1284 		     * hard way (see below).
1285 		     * First we have to make sure this reselection didn't
1286 		     * happen during Arbitration/Selection of some other device.
1287 		     * If yes, put losing command back on top of input_Q.
1288 		     */
1289 		    if (hostdata->level2 <= L2_NONE) {
1290 
1291 			if (hostdata->selecting) {
1292 				cmd = (struct scsi_cmnd *) hostdata->selecting;
1293 				hostdata->selecting = NULL;
1294 				hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1295 				cmd->host_scribble =
1296 				    (uchar *) hostdata->input_Q;
1297 				hostdata->input_Q = cmd;
1298 			}
1299 		}
1300 
1301 		else {
1302 
1303 			if (cmd) {
1304 				if (phs == 0x00) {
1305 					hostdata->busy[cmd->device->id] &=
1306 						~(1 << (cmd->device->lun & 0xff));
1307 					cmd->host_scribble =
1308 					    (uchar *) hostdata->input_Q;
1309 					hostdata->input_Q = cmd;
1310 				} else {
1311 					printk
1312 					    ("---%02x:%02x:%02x-TROUBLE: Intrusive ReSelect!---",
1313 					     asr, sr, phs);
1314 					while (1)
1315 						printk("\r");
1316 				}
1317 			}
1318 
1319 		}
1320 
1321 		/* OK - find out which device reselected us. */
1322 
1323 		id = read_wd33c93(regs, WD_SOURCE_ID);
1324 		id &= SRCID_MASK;
1325 
1326 		/* and extract the lun from the ID message. (Note that we don't
1327 		 * bother to check for a valid message here - I guess this is
1328 		 * not the right way to go, but...)
1329 		 */
1330 
1331 		if (sr == CSR_RESEL_AM) {
1332 			lun = read_wd33c93(regs, WD_DATA);
1333 			if (hostdata->level2 < L2_RESELECT)
1334 				write_wd33c93_cmd(regs, WD_CMD_NEGATE_ACK);
1335 			lun &= 7;
1336 		} else {
1337 			/* Old chip; wait for msgin phase to pick up the LUN. */
1338 			for (lun = 255; lun; lun--) {
1339 				if ((asr = read_aux_stat(regs)) & ASR_INT)
1340 					break;
1341 				udelay(10);
1342 			}
1343 			if (!(asr & ASR_INT)) {
1344 				printk
1345 				    ("wd33c93: Reselected without IDENTIFY\n");
1346 				lun = 0;
1347 			} else {
1348 				/* Verify this is a change to MSG_IN and read the message */
1349 				sr = read_wd33c93(regs, WD_SCSI_STATUS);
1350 				udelay(7);
1351 				if (sr == (CSR_ABORT | PHS_MESS_IN) ||
1352 				    sr == (CSR_UNEXP | PHS_MESS_IN) ||
1353 				    sr == (CSR_SRV_REQ | PHS_MESS_IN)) {
1354 					/* Got MSG_IN, grab target LUN */
1355 					lun = read_1_byte(regs);
1356 					/* Now we expect a 'paused with ACK asserted' int.. */
1357 					asr = read_aux_stat(regs);
1358 					if (!(asr & ASR_INT)) {
1359 						udelay(10);
1360 						asr = read_aux_stat(regs);
1361 						if (!(asr & ASR_INT))
1362 							printk
1363 							    ("wd33c93: No int after LUN on RESEL (%02x)\n",
1364 							     asr);
1365 					}
1366 					sr = read_wd33c93(regs, WD_SCSI_STATUS);
1367 					udelay(7);
1368 					if (sr != CSR_MSGIN)
1369 						printk
1370 						    ("wd33c93: Not paused with ACK on RESEL (%02x)\n",
1371 						     sr);
1372 					lun &= 7;
1373 					write_wd33c93_cmd(regs,
1374 							  WD_CMD_NEGATE_ACK);
1375 				} else {
1376 					printk
1377 					    ("wd33c93: Not MSG_IN on reselect (%02x)\n",
1378 					     sr);
1379 					lun = 0;
1380 				}
1381 			}
1382 		}
1383 
1384 		/* Now we look for the command that's reconnecting. */
1385 
1386 		cmd = (struct scsi_cmnd *) hostdata->disconnected_Q;
1387 		patch = NULL;
1388 		while (cmd) {
1389 			if (id == cmd->device->id && lun == (u8)cmd->device->lun)
1390 				break;
1391 			patch = cmd;
1392 			cmd = (struct scsi_cmnd *) cmd->host_scribble;
1393 		}
1394 
1395 		/* Hmm. Couldn't find a valid command.... What to do? */
1396 
1397 		if (!cmd) {
1398 			printk
1399 			    ("---TROUBLE: target %d.%d not in disconnect queue---",
1400 			     id, (u8)lun);
1401 			spin_unlock_irqrestore(&hostdata->lock, flags);
1402 			return;
1403 		}
1404 
1405 		/* Ok, found the command - now start it up again. */
1406 
1407 		if (patch)
1408 			patch->host_scribble = cmd->host_scribble;
1409 		else
1410 			hostdata->disconnected_Q =
1411 			    (struct scsi_cmnd *) cmd->host_scribble;
1412 		hostdata->connected = cmd;
1413 
1414 		/* We don't need to worry about 'initialize_SCp()' or 'hostdata->busy[]'
1415 		 * because these things are preserved over a disconnect.
1416 		 * But we DO need to fix the DPD bit so it's correct for this command.
1417 		 */
1418 
1419 		if (cmd->sc_data_direction == DMA_TO_DEVICE)
1420 			write_wd33c93(regs, WD_DESTINATION_ID, cmd->device->id);
1421 		else
1422 			write_wd33c93(regs, WD_DESTINATION_ID,
1423 				      cmd->device->id | DSTID_DPD);
1424 		if (hostdata->level2 >= L2_RESELECT) {
1425 			write_wd33c93_count(regs, 0);	/* we want a DATA_PHASE interrupt */
1426 			write_wd33c93(regs, WD_COMMAND_PHASE, 0x45);
1427 			write_wd33c93_cmd(regs, WD_CMD_SEL_ATN_XFER);
1428 			hostdata->state = S_RUNNING_LEVEL2;
1429 		} else
1430 			hostdata->state = S_CONNECTED;
1431 
1432 		    spin_unlock_irqrestore(&hostdata->lock, flags);
1433 		break;
1434 
1435 	default:
1436 		printk("--UNKNOWN INTERRUPT:%02x:%02x:%02x--", asr, sr, phs);
1437 		spin_unlock_irqrestore(&hostdata->lock, flags);
1438 	}
1439 
1440 	DB(DB_INTR, printk("} "))
1441 
1442 }
1443 
1444 static void
reset_wd33c93(struct Scsi_Host * instance)1445 reset_wd33c93(struct Scsi_Host *instance)
1446 {
1447 	struct WD33C93_hostdata *hostdata =
1448 	    (struct WD33C93_hostdata *) instance->hostdata;
1449 	const wd33c93_regs regs = hostdata->regs;
1450 	uchar sr;
1451 
1452 #ifdef CONFIG_SGI_IP22
1453 	{
1454 		int busycount = 0;
1455 		extern void sgiwd93_reset(unsigned long);
1456 		/* wait 'til the chip gets some time for us */
1457 		while ((read_aux_stat(regs) & ASR_BSY) && busycount++ < 100)
1458 			udelay (10);
1459 	/*
1460  	 * there are scsi devices out there, which manage to lock up
1461 	 * the wd33c93 in a busy condition. In this state it won't
1462 	 * accept the reset command. The only way to solve this is to
1463  	 * give the chip a hardware reset (if possible). The code below
1464 	 * does this for the SGI Indy, where this is possible
1465 	 */
1466 	/* still busy ? */
1467 	if (read_aux_stat(regs) & ASR_BSY)
1468 		sgiwd93_reset(instance->base); /* yeah, give it the hard one */
1469 	}
1470 #endif
1471 
1472 	write_wd33c93(regs, WD_OWN_ID, OWNID_EAF | OWNID_RAF |
1473 		      instance->this_id | hostdata->clock_freq);
1474 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
1475 	write_wd33c93(regs, WD_SYNCHRONOUS_TRANSFER,
1476 		      calc_sync_xfer(hostdata->default_sx_per / 4,
1477 				     DEFAULT_SX_OFF, 0, hostdata->sx_table));
1478 	write_wd33c93(regs, WD_COMMAND, WD_CMD_RESET);
1479 
1480 
1481 #ifdef CONFIG_MVME147_SCSI
1482 	udelay(25);		/* The old wd33c93 on MVME147 needs this, at least */
1483 #endif
1484 
1485 	while (!(read_aux_stat(regs) & ASR_INT))
1486 		;
1487 	sr = read_wd33c93(regs, WD_SCSI_STATUS);
1488 
1489 	hostdata->microcode = read_wd33c93(regs, WD_CDB_1);
1490 	if (sr == 0x00)
1491 		hostdata->chip = C_WD33C93;
1492 	else if (sr == 0x01) {
1493 		write_wd33c93(regs, WD_QUEUE_TAG, 0xa5);	/* any random number */
1494 		sr = read_wd33c93(regs, WD_QUEUE_TAG);
1495 		if (sr == 0xa5) {
1496 			hostdata->chip = C_WD33C93B;
1497 			write_wd33c93(regs, WD_QUEUE_TAG, 0);
1498 		} else
1499 			hostdata->chip = C_WD33C93A;
1500 	} else
1501 		hostdata->chip = C_UNKNOWN_CHIP;
1502 
1503 	if (hostdata->chip != C_WD33C93B)	/* Fast SCSI unavailable */
1504 		hostdata->fast = 0;
1505 
1506 	write_wd33c93(regs, WD_TIMEOUT_PERIOD, TIMEOUT_PERIOD_VALUE);
1507 	write_wd33c93(regs, WD_CONTROL, CTRL_IDI | CTRL_EDI | CTRL_POLLED);
1508 }
1509 
1510 int
wd33c93_host_reset(struct scsi_cmnd * SCpnt)1511 wd33c93_host_reset(struct scsi_cmnd * SCpnt)
1512 {
1513 	struct Scsi_Host *instance;
1514 	struct WD33C93_hostdata *hostdata;
1515 	int i;
1516 
1517 	instance = SCpnt->device->host;
1518 	spin_lock_irq(instance->host_lock);
1519 	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1520 
1521 	printk("scsi%d: reset. ", instance->host_no);
1522 	disable_irq(instance->irq);
1523 
1524 	hostdata->dma_stop(instance, NULL, 0);
1525 	for (i = 0; i < 8; i++) {
1526 		hostdata->busy[i] = 0;
1527 		hostdata->sync_xfer[i] =
1528 			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
1529 					0, hostdata->sx_table);
1530 		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
1531 	}
1532 	hostdata->input_Q = NULL;
1533 	hostdata->selecting = NULL;
1534 	hostdata->connected = NULL;
1535 	hostdata->disconnected_Q = NULL;
1536 	hostdata->state = S_UNCONNECTED;
1537 	hostdata->dma = D_DMA_OFF;
1538 	hostdata->incoming_ptr = 0;
1539 	hostdata->outgoing_len = 0;
1540 
1541 	reset_wd33c93(instance);
1542 	SCpnt->result = DID_RESET << 16;
1543 	enable_irq(instance->irq);
1544 	spin_unlock_irq(instance->host_lock);
1545 	return SUCCESS;
1546 }
1547 
1548 int
wd33c93_abort(struct scsi_cmnd * cmd)1549 wd33c93_abort(struct scsi_cmnd * cmd)
1550 {
1551 	struct Scsi_Host *instance;
1552 	struct WD33C93_hostdata *hostdata;
1553 	wd33c93_regs regs;
1554 	struct scsi_cmnd *tmp, *prev;
1555 
1556 	disable_irq(cmd->device->host->irq);
1557 
1558 	instance = cmd->device->host;
1559 	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1560 	regs = hostdata->regs;
1561 
1562 /*
1563  * Case 1 : If the command hasn't been issued yet, we simply remove it
1564  *     from the input_Q.
1565  */
1566 
1567 	tmp = (struct scsi_cmnd *) hostdata->input_Q;
1568 	prev = NULL;
1569 	while (tmp) {
1570 		if (tmp == cmd) {
1571 			if (prev)
1572 				prev->host_scribble = cmd->host_scribble;
1573 			else
1574 				hostdata->input_Q =
1575 				    (struct scsi_cmnd *) cmd->host_scribble;
1576 			cmd->host_scribble = NULL;
1577 			cmd->result = DID_ABORT << 16;
1578 			printk
1579 			    ("scsi%d: Abort - removing command from input_Q. ",
1580 			     instance->host_no);
1581 			enable_irq(cmd->device->host->irq);
1582 			scsi_done(cmd);
1583 			return SUCCESS;
1584 		}
1585 		prev = tmp;
1586 		tmp = (struct scsi_cmnd *) tmp->host_scribble;
1587 	}
1588 
1589 /*
1590  * Case 2 : If the command is connected, we're going to fail the abort
1591  *     and let the high level SCSI driver retry at a later time or
1592  *     issue a reset.
1593  *
1594  *     Timeouts, and therefore aborted commands, will be highly unlikely
1595  *     and handling them cleanly in this situation would make the common
1596  *     case of noresets less efficient, and would pollute our code.  So,
1597  *     we fail.
1598  */
1599 
1600 	if (hostdata->connected == cmd) {
1601 		uchar sr, asr;
1602 		unsigned long timeout;
1603 
1604 		printk("scsi%d: Aborting connected command - ",
1605 		       instance->host_no);
1606 
1607 		printk("stopping DMA - ");
1608 		if (hostdata->dma == D_DMA_RUNNING) {
1609 			hostdata->dma_stop(instance, cmd, 0);
1610 			hostdata->dma = D_DMA_OFF;
1611 		}
1612 
1613 		printk("sending wd33c93 ABORT command - ");
1614 		write_wd33c93(regs, WD_CONTROL,
1615 			      CTRL_IDI | CTRL_EDI | CTRL_POLLED);
1616 		write_wd33c93_cmd(regs, WD_CMD_ABORT);
1617 
1618 /* Now we have to attempt to flush out the FIFO... */
1619 
1620 		printk("flushing fifo - ");
1621 		timeout = 1000000;
1622 		do {
1623 			asr = read_aux_stat(regs);
1624 			if (asr & ASR_DBR)
1625 				read_wd33c93(regs, WD_DATA);
1626 		} while (!(asr & ASR_INT) && timeout-- > 0);
1627 		sr = read_wd33c93(regs, WD_SCSI_STATUS);
1628 		printk
1629 		    ("asr=%02x, sr=%02x, %ld bytes un-transferred (timeout=%ld) - ",
1630 		     asr, sr, read_wd33c93_count(regs), timeout);
1631 
1632 		/*
1633 		 * Abort command processed.
1634 		 * Still connected.
1635 		 * We must disconnect.
1636 		 */
1637 
1638 		printk("sending wd33c93 DISCONNECT command - ");
1639 		write_wd33c93_cmd(regs, WD_CMD_DISCONNECT);
1640 
1641 		timeout = 1000000;
1642 		asr = read_aux_stat(regs);
1643 		while ((asr & ASR_CIP) && timeout-- > 0)
1644 			asr = read_aux_stat(regs);
1645 		sr = read_wd33c93(regs, WD_SCSI_STATUS);
1646 		printk("asr=%02x, sr=%02x.", asr, sr);
1647 
1648 		hostdata->busy[cmd->device->id] &= ~(1 << (cmd->device->lun & 0xff));
1649 		hostdata->connected = NULL;
1650 		hostdata->state = S_UNCONNECTED;
1651 		cmd->result = DID_ABORT << 16;
1652 
1653 /*      sti();*/
1654 		wd33c93_execute(instance);
1655 
1656 		enable_irq(cmd->device->host->irq);
1657 		scsi_done(cmd);
1658 		return SUCCESS;
1659 	}
1660 
1661 /*
1662  * Case 3: If the command is currently disconnected from the bus,
1663  * we're not going to expend much effort here: Let's just return
1664  * an ABORT_SNOOZE and hope for the best...
1665  */
1666 
1667 	tmp = (struct scsi_cmnd *) hostdata->disconnected_Q;
1668 	while (tmp) {
1669 		if (tmp == cmd) {
1670 			printk
1671 			    ("scsi%d: Abort - command found on disconnected_Q - ",
1672 			     instance->host_no);
1673 			printk("Abort SNOOZE. ");
1674 			enable_irq(cmd->device->host->irq);
1675 			return FAILED;
1676 		}
1677 		tmp = (struct scsi_cmnd *) tmp->host_scribble;
1678 	}
1679 
1680 /*
1681  * Case 4 : If we reached this point, the command was not found in any of
1682  *     the queues.
1683  *
1684  * We probably reached this point because of an unlikely race condition
1685  * between the command completing successfully and the abortion code,
1686  * so we won't panic, but we will notify the user in case something really
1687  * broke.
1688  */
1689 
1690 /*   sti();*/
1691 	wd33c93_execute(instance);
1692 
1693 	enable_irq(cmd->device->host->irq);
1694 	printk("scsi%d: warning : SCSI command probably completed successfully"
1695 	       "         before abortion. ", instance->host_no);
1696 	return FAILED;
1697 }
1698 
1699 #define MAX_WD33C93_HOSTS 4
1700 #define MAX_SETUP_ARGS ARRAY_SIZE(setup_args)
1701 #define SETUP_BUFFER_SIZE 200
1702 static char setup_buffer[SETUP_BUFFER_SIZE];
1703 static char setup_used[MAX_SETUP_ARGS];
1704 static int done_setup = 0;
1705 
1706 static int
wd33c93_setup(char * str)1707 wd33c93_setup(char *str)
1708 {
1709 	int i;
1710 	char *p1, *p2;
1711 
1712 	/* The kernel does some processing of the command-line before calling
1713 	 * this function: If it begins with any decimal or hex number arguments,
1714 	 * ints[0] = how many numbers found and ints[1] through [n] are the values
1715 	 * themselves. str points to where the non-numeric arguments (if any)
1716 	 * start: We do our own parsing of those. We construct synthetic 'nosync'
1717 	 * keywords out of numeric args (to maintain compatibility with older
1718 	 * versions) and then add the rest of the arguments.
1719 	 */
1720 
1721 	p1 = setup_buffer;
1722 	*p1 = '\0';
1723 	if (str)
1724 		strscpy(p1, str, SETUP_BUFFER_SIZE);
1725 	i = 0;
1726 	while (*p1 && (i < MAX_SETUP_ARGS)) {
1727 		p2 = strchr(p1, ',');
1728 		if (p2) {
1729 			*p2 = '\0';
1730 			if (p1 != p2)
1731 				setup_args[i] = p1;
1732 			p1 = p2 + 1;
1733 			i++;
1734 		} else {
1735 			setup_args[i] = p1;
1736 			break;
1737 		}
1738 	}
1739 	for (i = 0; i < MAX_SETUP_ARGS; i++)
1740 		setup_used[i] = 0;
1741 	done_setup = 1;
1742 
1743 	return 1;
1744 }
1745 __setup("wd33c93=", wd33c93_setup);
1746 
1747 /* check_setup_args() returns index if key found, 0 if not
1748  */
1749 static int
check_setup_args(char * key,int * flags,int * val,char * buf)1750 check_setup_args(char *key, int *flags, int *val, char *buf)
1751 {
1752 	int x;
1753 	char *cp;
1754 
1755 	for (x = 0; x < MAX_SETUP_ARGS; x++) {
1756 		if (setup_used[x])
1757 			continue;
1758 		if (!strncmp(setup_args[x], key, strlen(key)))
1759 			break;
1760 		if (!strncmp(setup_args[x], "next", strlen("next")))
1761 			return 0;
1762 	}
1763 	if (x == MAX_SETUP_ARGS)
1764 		return 0;
1765 	setup_used[x] = 1;
1766 	cp = setup_args[x] + strlen(key);
1767 	*val = -1;
1768 	if (*cp != ':')
1769 		return ++x;
1770 	cp++;
1771 	if ((*cp >= '0') && (*cp <= '9')) {
1772 		*val = simple_strtoul(cp, NULL, 0);
1773 	}
1774 	return ++x;
1775 }
1776 
1777 /*
1778  * Calculate internal data-transfer-clock cycle from input-clock
1779  * frequency (/MHz) and fill 'sx_table'.
1780  *
1781  * The original driver used to rely on a fixed sx_table, containing periods
1782  * for (only) the lower limits of the respective input-clock-frequency ranges
1783  * (8-10/12-15/16-20 MHz). Although it seems, that no problems occurred with
1784  * this setting so far, it might be desirable to adjust the transfer periods
1785  * closer to the really attached, possibly 25% higher, input-clock, since
1786  * - the wd33c93 may really use a significant shorter period, than it has
1787  *   negotiated (eg. thrashing the target, which expects 4/8MHz, with 5/10MHz
1788  *   instead).
1789  * - the wd33c93 may ask the target for a lower transfer rate, than the target
1790  *   is capable of (eg. negotiating for an assumed minimum of 252ns instead of
1791  *   possible 200ns, which indeed shows up in tests as an approx. 10% lower
1792  *   transfer rate).
1793  */
1794 static inline unsigned int
round_4(unsigned int x)1795 round_4(unsigned int x)
1796 {
1797 	switch (x & 3) {
1798 		case 1: --x;
1799 			break;
1800 		case 2: ++x;
1801 			fallthrough;
1802 		case 3: ++x;
1803 	}
1804 	return x;
1805 }
1806 
1807 static void
calc_sx_table(unsigned int mhz,struct sx_period sx_table[9])1808 calc_sx_table(unsigned int mhz, struct sx_period sx_table[9])
1809 {
1810 	unsigned int d, i;
1811 	if (mhz < 11)
1812 		d = 2;	/* divisor for  8-10 MHz input-clock */
1813 	else if (mhz < 16)
1814 		d = 3;	/* divisor for 12-15 MHz input-clock */
1815 	else
1816 		d = 4;	/* divisor for 16-20 MHz input-clock */
1817 
1818 	d = (100000 * d) / 2 / mhz; /* 100 x DTCC / nanosec */
1819 
1820 	sx_table[0].period_ns = 1;
1821 	sx_table[0].reg_value = 0x20;
1822 	for (i = 1; i < 8; i++) {
1823 		sx_table[i].period_ns = round_4((i+1)*d / 100);
1824 		sx_table[i].reg_value = (i+1)*0x10;
1825 	}
1826 	sx_table[7].reg_value = 0;
1827 	sx_table[8].period_ns = 0;
1828 	sx_table[8].reg_value = 0;
1829 }
1830 
1831 /*
1832  * check and, maybe, map an init- or "clock:"- argument.
1833  */
1834 static uchar
set_clk_freq(int freq,int * mhz)1835 set_clk_freq(int freq, int *mhz)
1836 {
1837 	int x = freq;
1838 	if (WD33C93_FS_8_10 == freq)
1839 		freq = 8;
1840 	else if (WD33C93_FS_12_15 == freq)
1841 		freq = 12;
1842 	else if (WD33C93_FS_16_20 == freq)
1843 		freq = 16;
1844 	else if (freq > 7 && freq < 11)
1845 		x = WD33C93_FS_8_10;
1846 		else if (freq > 11 && freq < 16)
1847 		x = WD33C93_FS_12_15;
1848 		else if (freq > 15 && freq < 21)
1849 		x = WD33C93_FS_16_20;
1850 	else {
1851 			/* Hmm, wouldn't it be safer to assume highest freq here? */
1852 		x = WD33C93_FS_8_10;
1853 		freq = 8;
1854 	}
1855 	*mhz = freq;
1856 	return x;
1857 }
1858 
1859 /*
1860  * to be used with the resync: fast: ... options
1861  */
set_resync(struct WD33C93_hostdata * hd,int mask)1862 static inline void set_resync ( struct WD33C93_hostdata *hd, int mask )
1863 {
1864 	int i;
1865 	for (i = 0; i < 8; i++)
1866 		if (mask & (1 << i))
1867 			hd->sync_stat[i] = SS_UNSET;
1868 }
1869 
1870 void
wd33c93_init(struct Scsi_Host * instance,const wd33c93_regs regs,dma_setup_t setup,dma_stop_t stop,int clock_freq)1871 wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs,
1872 	     dma_setup_t setup, dma_stop_t stop, int clock_freq)
1873 {
1874 	struct WD33C93_hostdata *hostdata;
1875 	int i;
1876 	int flags;
1877 	int val;
1878 	char buf[32];
1879 
1880 	if (!done_setup && setup_strings)
1881 		wd33c93_setup(setup_strings);
1882 
1883 	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1884 
1885 	hostdata->regs = regs;
1886 	hostdata->clock_freq = set_clk_freq(clock_freq, &i);
1887 	calc_sx_table(i, hostdata->sx_table);
1888 	hostdata->dma_setup = setup;
1889 	hostdata->dma_stop = stop;
1890 	hostdata->dma_bounce_buffer = NULL;
1891 	hostdata->dma_bounce_len = 0;
1892 	for (i = 0; i < 8; i++) {
1893 		hostdata->busy[i] = 0;
1894 		hostdata->sync_xfer[i] =
1895 			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
1896 					0, hostdata->sx_table);
1897 		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
1898 #ifdef PROC_STATISTICS
1899 		hostdata->cmd_cnt[i] = 0;
1900 		hostdata->disc_allowed_cnt[i] = 0;
1901 		hostdata->disc_done_cnt[i] = 0;
1902 #endif
1903 	}
1904 	hostdata->input_Q = NULL;
1905 	hostdata->selecting = NULL;
1906 	hostdata->connected = NULL;
1907 	hostdata->disconnected_Q = NULL;
1908 	hostdata->state = S_UNCONNECTED;
1909 	hostdata->dma = D_DMA_OFF;
1910 	hostdata->level2 = L2_BASIC;
1911 	hostdata->disconnect = DIS_ADAPTIVE;
1912 	hostdata->args = DEBUG_DEFAULTS;
1913 	hostdata->incoming_ptr = 0;
1914 	hostdata->outgoing_len = 0;
1915 	hostdata->default_sx_per = DEFAULT_SX_PER;
1916 	hostdata->no_dma = 0;	/* default is DMA enabled */
1917 
1918 #ifdef PROC_INTERFACE
1919 	hostdata->proc = PR_VERSION | PR_INFO | PR_STATISTICS |
1920 	    PR_CONNECTED | PR_INPUTQ | PR_DISCQ | PR_STOP;
1921 #ifdef PROC_STATISTICS
1922 	hostdata->dma_cnt = 0;
1923 	hostdata->pio_cnt = 0;
1924 	hostdata->int_cnt = 0;
1925 #endif
1926 #endif
1927 
1928 	if (check_setup_args("clock", &flags, &val, buf)) {
1929 		hostdata->clock_freq = set_clk_freq(val, &val);
1930 		calc_sx_table(val, hostdata->sx_table);
1931 	}
1932 
1933 	if (check_setup_args("nosync", &flags, &val, buf))
1934 		hostdata->no_sync = val;
1935 
1936 	if (check_setup_args("nodma", &flags, &val, buf))
1937 		hostdata->no_dma = (val == -1) ? 1 : val;
1938 
1939 	if (check_setup_args("period", &flags, &val, buf))
1940 		hostdata->default_sx_per =
1941 		    hostdata->sx_table[round_period((unsigned int) val,
1942 		                                    hostdata->sx_table)].period_ns;
1943 
1944 	if (check_setup_args("disconnect", &flags, &val, buf)) {
1945 		if ((val >= DIS_NEVER) && (val <= DIS_ALWAYS))
1946 			hostdata->disconnect = val;
1947 		else
1948 			hostdata->disconnect = DIS_ADAPTIVE;
1949 	}
1950 
1951 	if (check_setup_args("level2", &flags, &val, buf))
1952 		hostdata->level2 = val;
1953 
1954 	if (check_setup_args("debug", &flags, &val, buf))
1955 		hostdata->args = val & DB_MASK;
1956 
1957 	if (check_setup_args("burst", &flags, &val, buf))
1958 		hostdata->dma_mode = val ? CTRL_BURST:CTRL_DMA;
1959 
1960 	if (WD33C93_FS_16_20 == hostdata->clock_freq /* divisor 4 */
1961 		&& check_setup_args("fast", &flags, &val, buf))
1962 		hostdata->fast = !!val;
1963 
1964 	if ((i = check_setup_args("next", &flags, &val, buf))) {
1965 		while (i)
1966 			setup_used[--i] = 1;
1967 	}
1968 #ifdef PROC_INTERFACE
1969 	if (check_setup_args("proc", &flags, &val, buf))
1970 		hostdata->proc = val;
1971 #endif
1972 
1973 	spin_lock_irq(&hostdata->lock);
1974 	reset_wd33c93(instance);
1975 	spin_unlock_irq(&hostdata->lock);
1976 
1977 	printk("wd33c93-%d: chip=%s/%d no_sync=0x%x no_dma=%d",
1978 	       instance->host_no,
1979 	       (hostdata->chip == C_WD33C93) ? "WD33c93" : (hostdata->chip ==
1980 							    C_WD33C93A) ?
1981 	       "WD33c93A" : (hostdata->chip ==
1982 			     C_WD33C93B) ? "WD33c93B" : "unknown",
1983 	       hostdata->microcode, hostdata->no_sync, hostdata->no_dma);
1984 #ifdef DEBUGGING_ON
1985 	printk(" debug_flags=0x%02x\n", hostdata->args);
1986 #else
1987 	printk(" debugging=OFF\n");
1988 #endif
1989 	printk("           setup_args=");
1990 	for (i = 0; i < MAX_SETUP_ARGS; i++)
1991 		printk("%s,", setup_args[i]);
1992 	printk("\n");
1993 	printk("           Version %s - %s\n", WD33C93_VERSION, WD33C93_DATE);
1994 }
1995 
wd33c93_write_info(struct Scsi_Host * instance,char * buf,int len)1996 int wd33c93_write_info(struct Scsi_Host *instance, char *buf, int len)
1997 {
1998 #ifdef PROC_INTERFACE
1999 	char *bp;
2000 	struct WD33C93_hostdata *hd;
2001 	int x;
2002 
2003 	hd = (struct WD33C93_hostdata *) instance->hostdata;
2004 
2005 /* We accept the following
2006  * keywords (same format as command-line, but arguments are not optional):
2007  *    debug
2008  *    disconnect
2009  *    period
2010  *    resync
2011  *    proc
2012  *    nodma
2013  *    level2
2014  *    burst
2015  *    fast
2016  *    nosync
2017  */
2018 
2019 	buf[len] = '\0';
2020 	for (bp = buf; *bp; ) {
2021 		while (',' == *bp || ' ' == *bp)
2022 			++bp;
2023 	if (!strncmp(bp, "debug:", 6)) {
2024 			hd->args = simple_strtoul(bp+6, &bp, 0) & DB_MASK;
2025 	} else if (!strncmp(bp, "disconnect:", 11)) {
2026 			x = simple_strtoul(bp+11, &bp, 0);
2027 		if (x < DIS_NEVER || x > DIS_ALWAYS)
2028 			x = DIS_ADAPTIVE;
2029 		hd->disconnect = x;
2030 	} else if (!strncmp(bp, "period:", 7)) {
2031 		x = simple_strtoul(bp+7, &bp, 0);
2032 		hd->default_sx_per =
2033 			hd->sx_table[round_period((unsigned int) x,
2034 						  hd->sx_table)].period_ns;
2035 	} else if (!strncmp(bp, "resync:", 7)) {
2036 			set_resync(hd, (int)simple_strtoul(bp+7, &bp, 0));
2037 	} else if (!strncmp(bp, "proc:", 5)) {
2038 			hd->proc = simple_strtoul(bp+5, &bp, 0);
2039 	} else if (!strncmp(bp, "nodma:", 6)) {
2040 			hd->no_dma = simple_strtoul(bp+6, &bp, 0);
2041 	} else if (!strncmp(bp, "level2:", 7)) {
2042 			hd->level2 = simple_strtoul(bp+7, &bp, 0);
2043 		} else if (!strncmp(bp, "burst:", 6)) {
2044 			hd->dma_mode =
2045 				simple_strtol(bp+6, &bp, 0) ? CTRL_BURST:CTRL_DMA;
2046 		} else if (!strncmp(bp, "fast:", 5)) {
2047 			x = !!simple_strtol(bp+5, &bp, 0);
2048 			if (x != hd->fast)
2049 				set_resync(hd, 0xff);
2050 			hd->fast = x;
2051 		} else if (!strncmp(bp, "nosync:", 7)) {
2052 			x = simple_strtoul(bp+7, &bp, 0);
2053 			set_resync(hd, x ^ hd->no_sync);
2054 			hd->no_sync = x;
2055 		} else {
2056 			break; /* unknown keyword,syntax-error,... */
2057 		}
2058 	}
2059 	return len;
2060 #else
2061 	return 0;
2062 #endif
2063 }
2064 
2065 int
wd33c93_show_info(struct seq_file * m,struct Scsi_Host * instance)2066 wd33c93_show_info(struct seq_file *m, struct Scsi_Host *instance)
2067 {
2068 #ifdef PROC_INTERFACE
2069 	struct WD33C93_hostdata *hd;
2070 	struct scsi_cmnd *cmd;
2071 	int x;
2072 
2073 	hd = (struct WD33C93_hostdata *) instance->hostdata;
2074 
2075 	spin_lock_irq(&hd->lock);
2076 	if (hd->proc & PR_VERSION)
2077 		seq_printf(m, "\nVersion %s - %s.",
2078 			WD33C93_VERSION, WD33C93_DATE);
2079 
2080 	if (hd->proc & PR_INFO) {
2081 		seq_printf(m, "\nclock_freq=%02x no_sync=%02x no_dma=%d"
2082 			" dma_mode=%02x fast=%d",
2083 			hd->clock_freq, hd->no_sync, hd->no_dma, hd->dma_mode, hd->fast);
2084 		seq_puts(m, "\nsync_xfer[] =       ");
2085 		for (x = 0; x < 7; x++)
2086 			seq_printf(m, "\t%02x", hd->sync_xfer[x]);
2087 		seq_puts(m, "\nsync_stat[] =       ");
2088 		for (x = 0; x < 7; x++)
2089 			seq_printf(m, "\t%02x", hd->sync_stat[x]);
2090 	}
2091 #ifdef PROC_STATISTICS
2092 	if (hd->proc & PR_STATISTICS) {
2093 		seq_puts(m, "\ncommands issued:    ");
2094 		for (x = 0; x < 7; x++)
2095 			seq_printf(m, "\t%ld", hd->cmd_cnt[x]);
2096 		seq_puts(m, "\ndisconnects allowed:");
2097 		for (x = 0; x < 7; x++)
2098 			seq_printf(m, "\t%ld", hd->disc_allowed_cnt[x]);
2099 		seq_puts(m, "\ndisconnects done:   ");
2100 		for (x = 0; x < 7; x++)
2101 			seq_printf(m, "\t%ld", hd->disc_done_cnt[x]);
2102 		seq_printf(m,
2103 			"\ninterrupts: %ld, DATA_PHASE ints: %ld DMA, %ld PIO",
2104 			hd->int_cnt, hd->dma_cnt, hd->pio_cnt);
2105 	}
2106 #endif
2107 	if (hd->proc & PR_CONNECTED) {
2108 		seq_puts(m, "\nconnected:     ");
2109 		if (hd->connected) {
2110 			cmd = (struct scsi_cmnd *) hd->connected;
2111 			seq_printf(m, " %d:%llu(%02x)",
2112 				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2113 		}
2114 	}
2115 	if (hd->proc & PR_INPUTQ) {
2116 		seq_puts(m, "\ninput_Q:       ");
2117 		cmd = (struct scsi_cmnd *) hd->input_Q;
2118 		while (cmd) {
2119 			seq_printf(m, " %d:%llu(%02x)",
2120 				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2121 			cmd = (struct scsi_cmnd *) cmd->host_scribble;
2122 		}
2123 	}
2124 	if (hd->proc & PR_DISCQ) {
2125 		seq_puts(m, "\ndisconnected_Q:");
2126 		cmd = (struct scsi_cmnd *) hd->disconnected_Q;
2127 		while (cmd) {
2128 			seq_printf(m, " %d:%llu(%02x)",
2129 				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2130 			cmd = (struct scsi_cmnd *) cmd->host_scribble;
2131 		}
2132 	}
2133 	seq_putc(m, '\n');
2134 	spin_unlock_irq(&hd->lock);
2135 #endif				/* PROC_INTERFACE */
2136 	return 0;
2137 }
2138 
2139 EXPORT_SYMBOL(wd33c93_host_reset);
2140 EXPORT_SYMBOL(wd33c93_init);
2141 EXPORT_SYMBOL(wd33c93_abort);
2142 EXPORT_SYMBOL(wd33c93_queuecommand);
2143 EXPORT_SYMBOL(wd33c93_intr);
2144 EXPORT_SYMBOL(wd33c93_show_info);
2145 EXPORT_SYMBOL(wd33c93_write_info);
2146