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
93MODULE_AUTHOR("John Shifflett");
94MODULE_DESCRIPTION("Generic WD33C93 SCSI driver");
95MODULE_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 */
158static char *setup_args[] = { "", "", "", "", "", "", "", "", "", "" };
159
160static char *setup_strings;
161module_param(setup_strings, charp, 0);
162
163static void wd33c93_execute(struct Scsi_Host *instance);
164
165static inline uchar
166read_wd33c93(const wd33c93_regs regs, uchar reg_num)
167{
168	*regs.SASR = reg_num;
169	mb();
170	return (*regs.SCMD);
171}
172
173static unsigned long
174read_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
187static inline uchar
188read_aux_stat(const wd33c93_regs regs)
189{
190	return *regs.SASR;
191}
192
193static inline void
194write_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
202static void
203write_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
213static inline void
214write_wd33c93_cmd(const wd33c93_regs regs, uchar cmd)
215{
216	*regs.SASR = WD_COMMAND;
217	mb();
218	*regs.SCMD = cmd;
219	mb();
220}
221
222static inline void
223write_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
232static inline uchar
233read_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
248static int
249round_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 */
265static uchar
266calc_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 */
290static inline void
291calc_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
305static 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
399DEF_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 */
411static void
412wd33c93_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
624static void
625transfer_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
659static void
660transfer_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
733void
734wd33c93_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 (scsi_pointer->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
1444static void
1445reset_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
1510int
1511wd33c93_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
1548int
1549wd33c93_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
1702static char setup_buffer[SETUP_BUFFER_SIZE];
1703static char setup_used[MAX_SETUP_ARGS];
1704static int done_setup = 0;
1705
1706static int
1707wd33c93_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		strncpy(p1, str, SETUP_BUFFER_SIZE - strlen(setup_buffer));
1725	setup_buffer[SETUP_BUFFER_SIZE - 1] = '\0';
1726	p1 = setup_buffer;
1727	i = 0;
1728	while (*p1 && (i < MAX_SETUP_ARGS)) {
1729		p2 = strchr(p1, ',');
1730		if (p2) {
1731			*p2 = '\0';
1732			if (p1 != p2)
1733				setup_args[i] = p1;
1734			p1 = p2 + 1;
1735			i++;
1736		} else {
1737			setup_args[i] = p1;
1738			break;
1739		}
1740	}
1741	for (i = 0; i < MAX_SETUP_ARGS; i++)
1742		setup_used[i] = 0;
1743	done_setup = 1;
1744
1745	return 1;
1746}
1747__setup("wd33c93=", wd33c93_setup);
1748
1749/* check_setup_args() returns index if key found, 0 if not
1750 */
1751static int
1752check_setup_args(char *key, int *flags, int *val, char *buf)
1753{
1754	int x;
1755	char *cp;
1756
1757	for (x = 0; x < MAX_SETUP_ARGS; x++) {
1758		if (setup_used[x])
1759			continue;
1760		if (!strncmp(setup_args[x], key, strlen(key)))
1761			break;
1762		if (!strncmp(setup_args[x], "next", strlen("next")))
1763			return 0;
1764	}
1765	if (x == MAX_SETUP_ARGS)
1766		return 0;
1767	setup_used[x] = 1;
1768	cp = setup_args[x] + strlen(key);
1769	*val = -1;
1770	if (*cp != ':')
1771		return ++x;
1772	cp++;
1773	if ((*cp >= '0') && (*cp <= '9')) {
1774		*val = simple_strtoul(cp, NULL, 0);
1775	}
1776	return ++x;
1777}
1778
1779/*
1780 * Calculate internal data-transfer-clock cycle from input-clock
1781 * frequency (/MHz) and fill 'sx_table'.
1782 *
1783 * The original driver used to rely on a fixed sx_table, containing periods
1784 * for (only) the lower limits of the respective input-clock-frequency ranges
1785 * (8-10/12-15/16-20 MHz). Although it seems, that no problems occurred with
1786 * this setting so far, it might be desirable to adjust the transfer periods
1787 * closer to the really attached, possibly 25% higher, input-clock, since
1788 * - the wd33c93 may really use a significant shorter period, than it has
1789 *   negotiated (eg. thrashing the target, which expects 4/8MHz, with 5/10MHz
1790 *   instead).
1791 * - the wd33c93 may ask the target for a lower transfer rate, than the target
1792 *   is capable of (eg. negotiating for an assumed minimum of 252ns instead of
1793 *   possible 200ns, which indeed shows up in tests as an approx. 10% lower
1794 *   transfer rate).
1795 */
1796static inline unsigned int
1797round_4(unsigned int x)
1798{
1799	switch (x & 3) {
1800		case 1: --x;
1801			break;
1802		case 2: ++x;
1803			fallthrough;
1804		case 3: ++x;
1805	}
1806	return x;
1807}
1808
1809static void
1810calc_sx_table(unsigned int mhz, struct sx_period sx_table[9])
1811{
1812	unsigned int d, i;
1813	if (mhz < 11)
1814		d = 2;	/* divisor for  8-10 MHz input-clock */
1815	else if (mhz < 16)
1816		d = 3;	/* divisor for 12-15 MHz input-clock */
1817	else
1818		d = 4;	/* divisor for 16-20 MHz input-clock */
1819
1820	d = (100000 * d) / 2 / mhz; /* 100 x DTCC / nanosec */
1821
1822	sx_table[0].period_ns = 1;
1823	sx_table[0].reg_value = 0x20;
1824	for (i = 1; i < 8; i++) {
1825		sx_table[i].period_ns = round_4((i+1)*d / 100);
1826		sx_table[i].reg_value = (i+1)*0x10;
1827	}
1828	sx_table[7].reg_value = 0;
1829	sx_table[8].period_ns = 0;
1830	sx_table[8].reg_value = 0;
1831}
1832
1833/*
1834 * check and, maybe, map an init- or "clock:"- argument.
1835 */
1836static uchar
1837set_clk_freq(int freq, int *mhz)
1838{
1839	int x = freq;
1840	if (WD33C93_FS_8_10 == freq)
1841		freq = 8;
1842	else if (WD33C93_FS_12_15 == freq)
1843		freq = 12;
1844	else if (WD33C93_FS_16_20 == freq)
1845		freq = 16;
1846	else if (freq > 7 && freq < 11)
1847		x = WD33C93_FS_8_10;
1848		else if (freq > 11 && freq < 16)
1849		x = WD33C93_FS_12_15;
1850		else if (freq > 15 && freq < 21)
1851		x = WD33C93_FS_16_20;
1852	else {
1853			/* Hmm, wouldn't it be safer to assume highest freq here? */
1854		x = WD33C93_FS_8_10;
1855		freq = 8;
1856	}
1857	*mhz = freq;
1858	return x;
1859}
1860
1861/*
1862 * to be used with the resync: fast: ... options
1863 */
1864static inline void set_resync ( struct WD33C93_hostdata *hd, int mask )
1865{
1866	int i;
1867	for (i = 0; i < 8; i++)
1868		if (mask & (1 << i))
1869			hd->sync_stat[i] = SS_UNSET;
1870}
1871
1872void
1873wd33c93_init(struct Scsi_Host *instance, const wd33c93_regs regs,
1874	     dma_setup_t setup, dma_stop_t stop, int clock_freq)
1875{
1876	struct WD33C93_hostdata *hostdata;
1877	int i;
1878	int flags;
1879	int val;
1880	char buf[32];
1881
1882	if (!done_setup && setup_strings)
1883		wd33c93_setup(setup_strings);
1884
1885	hostdata = (struct WD33C93_hostdata *) instance->hostdata;
1886
1887	hostdata->regs = regs;
1888	hostdata->clock_freq = set_clk_freq(clock_freq, &i);
1889	calc_sx_table(i, hostdata->sx_table);
1890	hostdata->dma_setup = setup;
1891	hostdata->dma_stop = stop;
1892	hostdata->dma_bounce_buffer = NULL;
1893	hostdata->dma_bounce_len = 0;
1894	for (i = 0; i < 8; i++) {
1895		hostdata->busy[i] = 0;
1896		hostdata->sync_xfer[i] =
1897			calc_sync_xfer(DEFAULT_SX_PER / 4, DEFAULT_SX_OFF,
1898					0, hostdata->sx_table);
1899		hostdata->sync_stat[i] = SS_UNSET;	/* using default sync values */
1900#ifdef PROC_STATISTICS
1901		hostdata->cmd_cnt[i] = 0;
1902		hostdata->disc_allowed_cnt[i] = 0;
1903		hostdata->disc_done_cnt[i] = 0;
1904#endif
1905	}
1906	hostdata->input_Q = NULL;
1907	hostdata->selecting = NULL;
1908	hostdata->connected = NULL;
1909	hostdata->disconnected_Q = NULL;
1910	hostdata->state = S_UNCONNECTED;
1911	hostdata->dma = D_DMA_OFF;
1912	hostdata->level2 = L2_BASIC;
1913	hostdata->disconnect = DIS_ADAPTIVE;
1914	hostdata->args = DEBUG_DEFAULTS;
1915	hostdata->incoming_ptr = 0;
1916	hostdata->outgoing_len = 0;
1917	hostdata->default_sx_per = DEFAULT_SX_PER;
1918	hostdata->no_dma = 0;	/* default is DMA enabled */
1919
1920#ifdef PROC_INTERFACE
1921	hostdata->proc = PR_VERSION | PR_INFO | PR_STATISTICS |
1922	    PR_CONNECTED | PR_INPUTQ | PR_DISCQ | PR_STOP;
1923#ifdef PROC_STATISTICS
1924	hostdata->dma_cnt = 0;
1925	hostdata->pio_cnt = 0;
1926	hostdata->int_cnt = 0;
1927#endif
1928#endif
1929
1930	if (check_setup_args("clock", &flags, &val, buf)) {
1931		hostdata->clock_freq = set_clk_freq(val, &val);
1932		calc_sx_table(val, hostdata->sx_table);
1933	}
1934
1935	if (check_setup_args("nosync", &flags, &val, buf))
1936		hostdata->no_sync = val;
1937
1938	if (check_setup_args("nodma", &flags, &val, buf))
1939		hostdata->no_dma = (val == -1) ? 1 : val;
1940
1941	if (check_setup_args("period", &flags, &val, buf))
1942		hostdata->default_sx_per =
1943		    hostdata->sx_table[round_period((unsigned int) val,
1944		                                    hostdata->sx_table)].period_ns;
1945
1946	if (check_setup_args("disconnect", &flags, &val, buf)) {
1947		if ((val >= DIS_NEVER) && (val <= DIS_ALWAYS))
1948			hostdata->disconnect = val;
1949		else
1950			hostdata->disconnect = DIS_ADAPTIVE;
1951	}
1952
1953	if (check_setup_args("level2", &flags, &val, buf))
1954		hostdata->level2 = val;
1955
1956	if (check_setup_args("debug", &flags, &val, buf))
1957		hostdata->args = val & DB_MASK;
1958
1959	if (check_setup_args("burst", &flags, &val, buf))
1960		hostdata->dma_mode = val ? CTRL_BURST:CTRL_DMA;
1961
1962	if (WD33C93_FS_16_20 == hostdata->clock_freq /* divisor 4 */
1963		&& check_setup_args("fast", &flags, &val, buf))
1964		hostdata->fast = !!val;
1965
1966	if ((i = check_setup_args("next", &flags, &val, buf))) {
1967		while (i)
1968			setup_used[--i] = 1;
1969	}
1970#ifdef PROC_INTERFACE
1971	if (check_setup_args("proc", &flags, &val, buf))
1972		hostdata->proc = val;
1973#endif
1974
1975	spin_lock_irq(&hostdata->lock);
1976	reset_wd33c93(instance);
1977	spin_unlock_irq(&hostdata->lock);
1978
1979	printk("wd33c93-%d: chip=%s/%d no_sync=0x%x no_dma=%d",
1980	       instance->host_no,
1981	       (hostdata->chip == C_WD33C93) ? "WD33c93" : (hostdata->chip ==
1982							    C_WD33C93A) ?
1983	       "WD33c93A" : (hostdata->chip ==
1984			     C_WD33C93B) ? "WD33c93B" : "unknown",
1985	       hostdata->microcode, hostdata->no_sync, hostdata->no_dma);
1986#ifdef DEBUGGING_ON
1987	printk(" debug_flags=0x%02x\n", hostdata->args);
1988#else
1989	printk(" debugging=OFF\n");
1990#endif
1991	printk("           setup_args=");
1992	for (i = 0; i < MAX_SETUP_ARGS; i++)
1993		printk("%s,", setup_args[i]);
1994	printk("\n");
1995	printk("           Version %s - %s\n", WD33C93_VERSION, WD33C93_DATE);
1996}
1997
1998int wd33c93_write_info(struct Scsi_Host *instance, char *buf, int len)
1999{
2000#ifdef PROC_INTERFACE
2001	char *bp;
2002	struct WD33C93_hostdata *hd;
2003	int x;
2004
2005	hd = (struct WD33C93_hostdata *) instance->hostdata;
2006
2007/* We accept the following
2008 * keywords (same format as command-line, but arguments are not optional):
2009 *    debug
2010 *    disconnect
2011 *    period
2012 *    resync
2013 *    proc
2014 *    nodma
2015 *    level2
2016 *    burst
2017 *    fast
2018 *    nosync
2019 */
2020
2021	buf[len] = '\0';
2022	for (bp = buf; *bp; ) {
2023		while (',' == *bp || ' ' == *bp)
2024			++bp;
2025	if (!strncmp(bp, "debug:", 6)) {
2026			hd->args = simple_strtoul(bp+6, &bp, 0) & DB_MASK;
2027	} else if (!strncmp(bp, "disconnect:", 11)) {
2028			x = simple_strtoul(bp+11, &bp, 0);
2029		if (x < DIS_NEVER || x > DIS_ALWAYS)
2030			x = DIS_ADAPTIVE;
2031		hd->disconnect = x;
2032	} else if (!strncmp(bp, "period:", 7)) {
2033		x = simple_strtoul(bp+7, &bp, 0);
2034		hd->default_sx_per =
2035			hd->sx_table[round_period((unsigned int) x,
2036						  hd->sx_table)].period_ns;
2037	} else if (!strncmp(bp, "resync:", 7)) {
2038			set_resync(hd, (int)simple_strtoul(bp+7, &bp, 0));
2039	} else if (!strncmp(bp, "proc:", 5)) {
2040			hd->proc = simple_strtoul(bp+5, &bp, 0);
2041	} else if (!strncmp(bp, "nodma:", 6)) {
2042			hd->no_dma = simple_strtoul(bp+6, &bp, 0);
2043	} else if (!strncmp(bp, "level2:", 7)) {
2044			hd->level2 = simple_strtoul(bp+7, &bp, 0);
2045		} else if (!strncmp(bp, "burst:", 6)) {
2046			hd->dma_mode =
2047				simple_strtol(bp+6, &bp, 0) ? CTRL_BURST:CTRL_DMA;
2048		} else if (!strncmp(bp, "fast:", 5)) {
2049			x = !!simple_strtol(bp+5, &bp, 0);
2050			if (x != hd->fast)
2051				set_resync(hd, 0xff);
2052			hd->fast = x;
2053		} else if (!strncmp(bp, "nosync:", 7)) {
2054			x = simple_strtoul(bp+7, &bp, 0);
2055			set_resync(hd, x ^ hd->no_sync);
2056			hd->no_sync = x;
2057		} else {
2058			break; /* unknown keyword,syntax-error,... */
2059		}
2060	}
2061	return len;
2062#else
2063	return 0;
2064#endif
2065}
2066
2067int
2068wd33c93_show_info(struct seq_file *m, struct Scsi_Host *instance)
2069{
2070#ifdef PROC_INTERFACE
2071	struct WD33C93_hostdata *hd;
2072	struct scsi_cmnd *cmd;
2073	int x;
2074
2075	hd = (struct WD33C93_hostdata *) instance->hostdata;
2076
2077	spin_lock_irq(&hd->lock);
2078	if (hd->proc & PR_VERSION)
2079		seq_printf(m, "\nVersion %s - %s.",
2080			WD33C93_VERSION, WD33C93_DATE);
2081
2082	if (hd->proc & PR_INFO) {
2083		seq_printf(m, "\nclock_freq=%02x no_sync=%02x no_dma=%d"
2084			" dma_mode=%02x fast=%d",
2085			hd->clock_freq, hd->no_sync, hd->no_dma, hd->dma_mode, hd->fast);
2086		seq_puts(m, "\nsync_xfer[] =       ");
2087		for (x = 0; x < 7; x++)
2088			seq_printf(m, "\t%02x", hd->sync_xfer[x]);
2089		seq_puts(m, "\nsync_stat[] =       ");
2090		for (x = 0; x < 7; x++)
2091			seq_printf(m, "\t%02x", hd->sync_stat[x]);
2092	}
2093#ifdef PROC_STATISTICS
2094	if (hd->proc & PR_STATISTICS) {
2095		seq_puts(m, "\ncommands issued:    ");
2096		for (x = 0; x < 7; x++)
2097			seq_printf(m, "\t%ld", hd->cmd_cnt[x]);
2098		seq_puts(m, "\ndisconnects allowed:");
2099		for (x = 0; x < 7; x++)
2100			seq_printf(m, "\t%ld", hd->disc_allowed_cnt[x]);
2101		seq_puts(m, "\ndisconnects done:   ");
2102		for (x = 0; x < 7; x++)
2103			seq_printf(m, "\t%ld", hd->disc_done_cnt[x]);
2104		seq_printf(m,
2105			"\ninterrupts: %ld, DATA_PHASE ints: %ld DMA, %ld PIO",
2106			hd->int_cnt, hd->dma_cnt, hd->pio_cnt);
2107	}
2108#endif
2109	if (hd->proc & PR_CONNECTED) {
2110		seq_puts(m, "\nconnected:     ");
2111		if (hd->connected) {
2112			cmd = (struct scsi_cmnd *) hd->connected;
2113			seq_printf(m, " %d:%llu(%02x)",
2114				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2115		}
2116	}
2117	if (hd->proc & PR_INPUTQ) {
2118		seq_puts(m, "\ninput_Q:       ");
2119		cmd = (struct scsi_cmnd *) hd->input_Q;
2120		while (cmd) {
2121			seq_printf(m, " %d:%llu(%02x)",
2122				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2123			cmd = (struct scsi_cmnd *) cmd->host_scribble;
2124		}
2125	}
2126	if (hd->proc & PR_DISCQ) {
2127		seq_puts(m, "\ndisconnected_Q:");
2128		cmd = (struct scsi_cmnd *) hd->disconnected_Q;
2129		while (cmd) {
2130			seq_printf(m, " %d:%llu(%02x)",
2131				cmd->device->id, cmd->device->lun, cmd->cmnd[0]);
2132			cmd = (struct scsi_cmnd *) cmd->host_scribble;
2133		}
2134	}
2135	seq_putc(m, '\n');
2136	spin_unlock_irq(&hd->lock);
2137#endif				/* PROC_INTERFACE */
2138	return 0;
2139}
2140
2141EXPORT_SYMBOL(wd33c93_host_reset);
2142EXPORT_SYMBOL(wd33c93_init);
2143EXPORT_SYMBOL(wd33c93_abort);
2144EXPORT_SYMBOL(wd33c93_queuecommand);
2145EXPORT_SYMBOL(wd33c93_intr);
2146EXPORT_SYMBOL(wd33c93_show_info);
2147EXPORT_SYMBOL(wd33c93_write_info);
2148