xref: /openbmc/linux/drivers/scsi/arm/fas216.c (revision 9a29f5fc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/acorn/scsi/fas216.c
4  *
5  *  Copyright (C) 1997-2003 Russell King
6  *
7  * Based on information in qlogicfas.c by Tom Zerucha, Michael Griffith, and
8  * other sources, including:
9  *   the AMD Am53CF94 data sheet
10  *   the AMD Am53C94 data sheet
11  *
12  * This is a generic driver.  To use it, have a look at cumana_2.c.  You
13  * should define your own structure that overlays FAS216_Info, eg:
14  * struct my_host_data {
15  *    FAS216_Info info;
16  *    ... my host specific data ...
17  * };
18  *
19  * Changelog:
20  *  30-08-1997	RMK	Created
21  *  14-09-1997	RMK	Started disconnect support
22  *  08-02-1998	RMK	Corrected real DMA support
23  *  15-02-1998	RMK	Started sync xfer support
24  *  06-04-1998	RMK	Tightened conditions for printing incomplete
25  *			transfers
26  *  02-05-1998	RMK	Added extra checks in fas216_reset
27  *  24-05-1998	RMK	Fixed synchronous transfers with period >= 200ns
28  *  27-06-1998	RMK	Changed asm/delay.h to linux/delay.h
29  *  26-08-1998	RMK	Improved message support wrt MESSAGE_REJECT
30  *  02-04-2000	RMK	Converted to use the new error handling, and
31  *			automatically request sense data upon check
32  *			condition status from targets.
33  */
34 #include <linux/module.h>
35 #include <linux/blkdev.h>
36 #include <linux/kernel.h>
37 #include <linux/string.h>
38 #include <linux/ioport.h>
39 #include <linux/proc_fs.h>
40 #include <linux/delay.h>
41 #include <linux/bitops.h>
42 #include <linux/init.h>
43 #include <linux/interrupt.h>
44 
45 #include <asm/dma.h>
46 #include <asm/io.h>
47 #include <asm/irq.h>
48 #include <asm/ecard.h>
49 
50 #include <scsi/scsi.h>
51 #include <scsi/scsi_cmnd.h>
52 #include <scsi/scsi_dbg.h>
53 #include <scsi/scsi_device.h>
54 #include <scsi/scsi_eh.h>
55 #include <scsi/scsi_host.h>
56 #include <scsi/scsi_tcq.h>
57 #include "fas216.h"
58 #include "arm_scsi.h"
59 
60 /* NOTE: SCSI2 Synchronous transfers *require* DMA according to
61  *  the data sheet.  This restriction is crazy, especially when
62  *  you only want to send 16 bytes!  What were the guys who
63  *  designed this chip on at that time?  Did they read the SCSI2
64  *  spec at all?  The following sections are taken from the SCSI2
65  *  standard (s2r10) concerning this:
66  *
67  * > IMPLEMENTORS NOTES:
68  * >   (1)  Re-negotiation at every selection is not recommended, since a
69  * >   significant performance impact is likely.
70  *
71  * >  The implied synchronous agreement shall remain in effect until a BUS DEVICE
72  * >  RESET message is received, until a hard reset condition occurs, or until one
73  * >  of the two SCSI devices elects to modify the agreement.  The default data
74  * >  transfer mode is asynchronous data transfer mode.  The default data transfer
75  * >  mode is entered at power on, after a BUS DEVICE RESET message, or after a hard
76  * >  reset condition.
77  *
78  *  In total, this means that once you have elected to use synchronous
79  *  transfers, you must always use DMA.
80  *
81  *  I was thinking that this was a good chip until I found this restriction ;(
82  */
83 #define SCSI2_SYNC
84 
85 #undef DEBUG_CONNECT
86 #undef DEBUG_MESSAGES
87 
88 #undef CHECK_STRUCTURE
89 
90 #define LOG_CONNECT		(1 << 0)
91 #define LOG_BUSSERVICE		(1 << 1)
92 #define LOG_FUNCTIONDONE	(1 << 2)
93 #define LOG_MESSAGES		(1 << 3)
94 #define LOG_BUFFER		(1 << 4)
95 #define LOG_ERROR		(1 << 8)
96 
97 static int level_mask = LOG_ERROR;
98 
99 module_param(level_mask, int, 0644);
100 
101 #ifndef MODULE
102 static int __init fas216_log_setup(char *str)
103 {
104 	char *s;
105 
106 	level_mask = 0;
107 
108 	while ((s = strsep(&str, ",")) != NULL) {
109 		switch (s[0]) {
110 		case 'a':
111 			if (strcmp(s, "all") == 0)
112 				level_mask |= -1;
113 			break;
114 		case 'b':
115 			if (strncmp(s, "bus", 3) == 0)
116 				level_mask |= LOG_BUSSERVICE;
117 			if (strncmp(s, "buf", 3) == 0)
118 				level_mask |= LOG_BUFFER;
119 			break;
120 		case 'c':
121 			level_mask |= LOG_CONNECT;
122 			break;
123 		case 'e':
124 			level_mask |= LOG_ERROR;
125 			break;
126 		case 'm':
127 			level_mask |= LOG_MESSAGES;
128 			break;
129 		case 'n':
130 			if (strcmp(s, "none") == 0)
131 				level_mask = 0;
132 			break;
133 		case 's':
134 			level_mask |= LOG_FUNCTIONDONE;
135 			break;
136 		}
137 	}
138 	return 1;
139 }
140 
141 __setup("fas216_logging=", fas216_log_setup);
142 #endif
143 
144 static inline unsigned char fas216_readb(FAS216_Info *info, unsigned int reg)
145 {
146 	unsigned int off = reg << info->scsi.io_shift;
147 	return readb(info->scsi.io_base + off);
148 }
149 
150 static inline void fas216_writeb(FAS216_Info *info, unsigned int reg, unsigned int val)
151 {
152 	unsigned int off = reg << info->scsi.io_shift;
153 	writeb(val, info->scsi.io_base + off);
154 }
155 
156 static void fas216_dumpstate(FAS216_Info *info)
157 {
158 	unsigned char is, stat, inst;
159 
160 	is   = fas216_readb(info, REG_IS);
161 	stat = fas216_readb(info, REG_STAT);
162 	inst = fas216_readb(info, REG_INST);
163 
164 	printk("FAS216: CTCL=%02X CTCM=%02X CMD=%02X STAT=%02X"
165 	       " INST=%02X IS=%02X CFIS=%02X",
166 		fas216_readb(info, REG_CTCL),
167 		fas216_readb(info, REG_CTCM),
168 		fas216_readb(info, REG_CMD),  stat, inst, is,
169 		fas216_readb(info, REG_CFIS));
170 	printk(" CNTL1=%02X CNTL2=%02X CNTL3=%02X CTCH=%02X\n",
171 		fas216_readb(info, REG_CNTL1),
172 		fas216_readb(info, REG_CNTL2),
173 		fas216_readb(info, REG_CNTL3),
174 		fas216_readb(info, REG_CTCH));
175 }
176 
177 static void print_SCp(struct scsi_pointer *SCp, const char *prefix, const char *suffix)
178 {
179 	printk("%sptr %p this_residual 0x%x buffer %p buffers_residual 0x%x%s",
180 		prefix, SCp->ptr, SCp->this_residual, SCp->buffer,
181 		SCp->buffers_residual, suffix);
182 }
183 
184 #ifdef CHECK_STRUCTURE
185 static void fas216_dumpinfo(FAS216_Info *info)
186 {
187 	static int used = 0;
188 	int i;
189 
190 	if (used++)
191 		return;
192 
193 	printk("FAS216_Info=\n");
194 	printk("  { magic_start=%lX host=%p SCpnt=%p origSCpnt=%p\n",
195 		info->magic_start, info->host, info->SCpnt,
196 		info->origSCpnt);
197 	printk("    scsi={ io_shift=%X irq=%X cfg={ %X %X %X %X }\n",
198 		info->scsi.io_shift, info->scsi.irq,
199 		info->scsi.cfg[0], info->scsi.cfg[1], info->scsi.cfg[2],
200 		info->scsi.cfg[3]);
201 	printk("           type=%p phase=%X\n",
202 		info->scsi.type, info->scsi.phase);
203 	print_SCp(&info->scsi.SCp, "           SCp={ ", " }\n");
204 	printk("      msgs async_stp=%X disconnectable=%d aborting=%d }\n",
205 		info->scsi.async_stp,
206 		info->scsi.disconnectable, info->scsi.aborting);
207 	printk("    stats={ queues=%X removes=%X fins=%X reads=%X writes=%X miscs=%X\n"
208 	       "            disconnects=%X aborts=%X bus_resets=%X host_resets=%X}\n",
209 		info->stats.queues, info->stats.removes, info->stats.fins,
210 		info->stats.reads, info->stats.writes, info->stats.miscs,
211 		info->stats.disconnects, info->stats.aborts, info->stats.bus_resets,
212 		info->stats.host_resets);
213 	printk("    ifcfg={ clockrate=%X select_timeout=%X asyncperiod=%X sync_max_depth=%X }\n",
214 		info->ifcfg.clockrate, info->ifcfg.select_timeout,
215 		info->ifcfg.asyncperiod, info->ifcfg.sync_max_depth);
216 	for (i = 0; i < 8; i++) {
217 		printk("    busyluns[%d]=%08lx dev[%d]={ disconnect_ok=%d stp=%X sof=%X sync_state=%X }\n",
218 			i, info->busyluns[i], i,
219 			info->device[i].disconnect_ok, info->device[i].stp,
220 			info->device[i].sof, info->device[i].sync_state);
221 	}
222 	printk("    dma={ transfer_type=%X setup=%p pseudo=%p stop=%p }\n",
223 		info->dma.transfer_type, info->dma.setup,
224 		info->dma.pseudo, info->dma.stop);
225 	printk("    internal_done=%X magic_end=%lX }\n",
226 		info->internal_done, info->magic_end);
227 }
228 
229 static void __fas216_checkmagic(FAS216_Info *info, const char *func)
230 {
231 	int corruption = 0;
232 	if (info->magic_start != MAGIC) {
233 		printk(KERN_CRIT "FAS216 Error: magic at start corrupted\n");
234 		corruption++;
235 	}
236 	if (info->magic_end != MAGIC) {
237 		printk(KERN_CRIT "FAS216 Error: magic at end corrupted\n");
238 		corruption++;
239 	}
240 	if (corruption) {
241 		fas216_dumpinfo(info);
242 		panic("scsi memory space corrupted in %s", func);
243 	}
244 }
245 #define fas216_checkmagic(info) __fas216_checkmagic((info), __func__)
246 #else
247 #define fas216_checkmagic(info)
248 #endif
249 
250 static const char *fas216_bus_phase(int stat)
251 {
252 	static const char *phases[] = {
253 		"DATA OUT", "DATA IN",
254 		"COMMAND", "STATUS",
255 		"MISC OUT", "MISC IN",
256 		"MESG OUT", "MESG IN"
257 	};
258 
259 	return phases[stat & STAT_BUSMASK];
260 }
261 
262 static const char *fas216_drv_phase(FAS216_Info *info)
263 {
264 	static const char *phases[] = {
265 		[PHASE_IDLE]		= "idle",
266 		[PHASE_SELECTION]	= "selection",
267 		[PHASE_COMMAND]		= "command",
268 		[PHASE_DATAOUT]		= "data out",
269 		[PHASE_DATAIN]		= "data in",
270 		[PHASE_MSGIN]		= "message in",
271 		[PHASE_MSGIN_DISCONNECT]= "disconnect",
272 		[PHASE_MSGOUT_EXPECT]	= "expect message out",
273 		[PHASE_MSGOUT]		= "message out",
274 		[PHASE_STATUS]		= "status",
275 		[PHASE_DONE]		= "done",
276 	};
277 
278 	if (info->scsi.phase < ARRAY_SIZE(phases) &&
279 	    phases[info->scsi.phase])
280 		return phases[info->scsi.phase];
281 	return "???";
282 }
283 
284 static char fas216_target(FAS216_Info *info)
285 {
286 	if (info->SCpnt)
287 		return '0' + info->SCpnt->device->id;
288 	else
289 		return 'H';
290 }
291 
292 static void
293 fas216_do_log(FAS216_Info *info, char target, char *fmt, va_list ap)
294 {
295 	static char buf[1024];
296 
297 	vsnprintf(buf, sizeof(buf), fmt, ap);
298 	printk("scsi%d.%c: %s", info->host->host_no, target, buf);
299 }
300 
301 static void fas216_log_command(FAS216_Info *info, int level,
302 			       struct scsi_cmnd *SCpnt, char *fmt, ...)
303 {
304 	va_list args;
305 
306 	if (level != 0 && !(level & level_mask))
307 		return;
308 
309 	va_start(args, fmt);
310 	fas216_do_log(info, '0' + SCpnt->device->id, fmt, args);
311 	va_end(args);
312 
313 	scsi_print_command(SCpnt);
314 }
315 
316 static void
317 fas216_log_target(FAS216_Info *info, int level, int target, char *fmt, ...)
318 {
319 	va_list args;
320 
321 	if (level != 0 && !(level & level_mask))
322 		return;
323 
324 	if (target < 0)
325 		target = 'H';
326 	else
327 		target += '0';
328 
329 	va_start(args, fmt);
330 	fas216_do_log(info, target, fmt, args);
331 	va_end(args);
332 
333 	printk("\n");
334 }
335 
336 static void fas216_log(FAS216_Info *info, int level, char *fmt, ...)
337 {
338 	va_list args;
339 
340 	if (level != 0 && !(level & level_mask))
341 		return;
342 
343 	va_start(args, fmt);
344 	fas216_do_log(info, fas216_target(info), fmt, args);
345 	va_end(args);
346 
347 	printk("\n");
348 }
349 
350 #define PH_SIZE	32
351 
352 static struct { int stat, ssr, isr, ph; } ph_list[PH_SIZE];
353 static int ph_ptr;
354 
355 static void add_debug_list(int stat, int ssr, int isr, int ph)
356 {
357 	ph_list[ph_ptr].stat = stat;
358 	ph_list[ph_ptr].ssr = ssr;
359 	ph_list[ph_ptr].isr = isr;
360 	ph_list[ph_ptr].ph = ph;
361 
362 	ph_ptr = (ph_ptr + 1) & (PH_SIZE-1);
363 }
364 
365 static struct { int command; void *from; } cmd_list[8];
366 static int cmd_ptr;
367 
368 static void fas216_cmd(FAS216_Info *info, unsigned int command)
369 {
370 	cmd_list[cmd_ptr].command = command;
371 	cmd_list[cmd_ptr].from = __builtin_return_address(0);
372 
373 	cmd_ptr = (cmd_ptr + 1) & 7;
374 
375 	fas216_writeb(info, REG_CMD, command);
376 }
377 
378 static void print_debug_list(void)
379 {
380 	int i;
381 
382 	i = ph_ptr;
383 
384 	printk(KERN_ERR "SCSI IRQ trail\n");
385 	do {
386 		printk(" %02x:%02x:%02x:%1x",
387 			ph_list[i].stat, ph_list[i].ssr,
388 			ph_list[i].isr, ph_list[i].ph);
389 		i = (i + 1) & (PH_SIZE - 1);
390 		if (((i ^ ph_ptr) & 7) == 0)
391 			printk("\n");
392 	} while (i != ph_ptr);
393 	if ((i ^ ph_ptr) & 7)
394 		printk("\n");
395 
396 	i = cmd_ptr;
397 	printk(KERN_ERR "FAS216 commands: ");
398 	do {
399 		printk("%02x:%p ", cmd_list[i].command, cmd_list[i].from);
400 		i = (i + 1) & 7;
401 	} while (i != cmd_ptr);
402 	printk("\n");
403 }
404 
405 static void fas216_done(FAS216_Info *info, unsigned int result);
406 
407 /**
408  * fas216_get_last_msg - retrive last message from the list
409  * @info: interface to search
410  * @pos: current fifo position
411  *
412  * Retrieve a last message from the list, using position in fifo.
413  */
414 static inline unsigned short
415 fas216_get_last_msg(FAS216_Info *info, int pos)
416 {
417 	unsigned short packed_msg = NOP;
418 	struct message *msg;
419 	int msgnr = 0;
420 
421 	while ((msg = msgqueue_getmsg(&info->scsi.msgs, msgnr++)) != NULL) {
422 		if (pos >= msg->fifo)
423 			break;
424 	}
425 
426 	if (msg) {
427 		if (msg->msg[0] == EXTENDED_MESSAGE)
428 			packed_msg = EXTENDED_MESSAGE | msg->msg[2] << 8;
429 		else
430 			packed_msg = msg->msg[0];
431 	}
432 
433 	fas216_log(info, LOG_MESSAGES,
434 		"Message: %04x found at position %02x\n", packed_msg, pos);
435 
436 	return packed_msg;
437 }
438 
439 /**
440  * fas216_syncperiod - calculate STP register value
441  * @info: state structure for interface connected to device
442  * @ns: period in ns (between subsequent bytes)
443  *
444  * Calculate value to be loaded into the STP register for a given period
445  * in ns. Returns a value suitable for REG_STP.
446  */
447 static int fas216_syncperiod(FAS216_Info *info, int ns)
448 {
449 	int value = (info->ifcfg.clockrate * ns) / 1000;
450 
451 	fas216_checkmagic(info);
452 
453 	if (value < 4)
454 		value = 4;
455 	else if (value > 35)
456 		value = 35;
457 
458 	return value & 31;
459 }
460 
461 /**
462  * fas216_set_sync - setup FAS216 chip for specified transfer period.
463  * @info: state structure for interface connected to device
464  * @target: target
465  *
466  * Correctly setup FAS216 chip for specified transfer period.
467  * Notes   : we need to switch the chip out of FASTSCSI mode if we have
468  *           a transfer period >= 200ns - otherwise the chip will violate
469  *           the SCSI timings.
470  */
471 static void fas216_set_sync(FAS216_Info *info, int target)
472 {
473 	unsigned int cntl3;
474 
475 	fas216_writeb(info, REG_SOF, info->device[target].sof);
476 	fas216_writeb(info, REG_STP, info->device[target].stp);
477 
478 	cntl3 = info->scsi.cfg[2];
479 	if (info->device[target].period >= (200 / 4))
480 		cntl3 = cntl3 & ~CNTL3_FASTSCSI;
481 
482 	fas216_writeb(info, REG_CNTL3, cntl3);
483 }
484 
485 /* Synchronous transfer support
486  *
487  * Note: The SCSI II r10 spec says (5.6.12):
488  *
489  *  (2)  Due to historical problems with early host adapters that could
490  *  not accept an SDTR message, some targets may not initiate synchronous
491  *  negotiation after a power cycle as required by this standard.  Host
492  *  adapters that support synchronous mode may avoid the ensuing failure
493  *  modes when the target is independently power cycled by initiating a
494  *  synchronous negotiation on each REQUEST SENSE and INQUIRY command.
495  *  This approach increases the SCSI bus overhead and is not recommended
496  *  for new implementations.  The correct method is to respond to an
497  *  SDTR message with a MESSAGE REJECT message if the either the
498  *  initiator or target devices does not support synchronous transfers
499  *  or does not want to negotiate for synchronous transfers at the time.
500  *  Using the correct method assures compatibility with wide data
501  *  transfers and future enhancements.
502  *
503  * We will always initiate a synchronous transfer negotiation request on
504  * every INQUIRY or REQUEST SENSE message, unless the target itself has
505  * at some point performed a synchronous transfer negotiation request, or
506  * we have synchronous transfers disabled for this device.
507  */
508 
509 /**
510  * fas216_handlesync - Handle a synchronous transfer message
511  * @info: state structure for interface
512  * @msg: message from target
513  *
514  * Handle a synchronous transfer message from the target
515  */
516 static void fas216_handlesync(FAS216_Info *info, char *msg)
517 {
518 	struct fas216_device *dev = &info->device[info->SCpnt->device->id];
519 	enum { sync, async, none, reject } res = none;
520 
521 #ifdef SCSI2_SYNC
522 	switch (msg[0]) {
523 	case MESSAGE_REJECT:
524 		/* Synchronous transfer request failed.
525 		 * Note: SCSI II r10:
526 		 *
527 		 *  SCSI devices that are capable of synchronous
528 		 *  data transfers shall not respond to an SDTR
529 		 *  message with a MESSAGE REJECT message.
530 		 *
531 		 * Hence, if we get this condition, we disable
532 		 * negotiation for this device.
533 		 */
534 		if (dev->sync_state == neg_inprogress) {
535 			dev->sync_state = neg_invalid;
536 			res = async;
537 		}
538 		break;
539 
540 	case EXTENDED_MESSAGE:
541 		switch (dev->sync_state) {
542 		/* We don't accept synchronous transfer requests.
543 		 * Respond with a MESSAGE_REJECT to prevent a
544 		 * synchronous transfer agreement from being reached.
545 		 */
546 		case neg_invalid:
547 			res = reject;
548 			break;
549 
550 		/* We were not negotiating a synchronous transfer,
551 		 * but the device sent us a negotiation request.
552 		 * Honour the request by sending back a SDTR
553 		 * message containing our capability, limited by
554 		 * the targets capability.
555 		 */
556 		default:
557 			fas216_cmd(info, CMD_SETATN);
558 			if (msg[4] > info->ifcfg.sync_max_depth)
559 				msg[4] = info->ifcfg.sync_max_depth;
560 			if (msg[3] < 1000 / info->ifcfg.clockrate)
561 				msg[3] = 1000 / info->ifcfg.clockrate;
562 
563 			msgqueue_flush(&info->scsi.msgs);
564 			msgqueue_addmsg(&info->scsi.msgs, 5,
565 					EXTENDED_MESSAGE, 3, EXTENDED_SDTR,
566 					msg[3], msg[4]);
567 			info->scsi.phase = PHASE_MSGOUT_EXPECT;
568 
569 			/* This is wrong.  The agreement is not in effect
570 			 * until this message is accepted by the device
571 			 */
572 			dev->sync_state = neg_targcomplete;
573 			res = sync;
574 			break;
575 
576 		/* We initiated the synchronous transfer negotiation,
577 		 * and have successfully received a response from the
578 		 * target.  The synchronous transfer agreement has been
579 		 * reached.  Note: if the values returned are out of our
580 		 * bounds, we must reject the message.
581 		 */
582 		case neg_inprogress:
583 			res = reject;
584 			if (msg[4] <= info->ifcfg.sync_max_depth &&
585 			    msg[3] >= 1000 / info->ifcfg.clockrate) {
586 				dev->sync_state = neg_complete;
587 				res = sync;
588 			}
589 			break;
590 		}
591 	}
592 #else
593 	res = reject;
594 #endif
595 
596 	switch (res) {
597 	case sync:
598 		dev->period = msg[3];
599 		dev->sof    = msg[4];
600 		dev->stp    = fas216_syncperiod(info, msg[3] * 4);
601 		fas216_set_sync(info, info->SCpnt->device->id);
602 		break;
603 
604 	case reject:
605 		fas216_cmd(info, CMD_SETATN);
606 		msgqueue_flush(&info->scsi.msgs);
607 		msgqueue_addmsg(&info->scsi.msgs, 1, MESSAGE_REJECT);
608 		info->scsi.phase = PHASE_MSGOUT_EXPECT;
609 		fallthrough;
610 
611 	case async:
612 		dev->period = info->ifcfg.asyncperiod / 4;
613 		dev->sof    = 0;
614 		dev->stp    = info->scsi.async_stp;
615 		fas216_set_sync(info, info->SCpnt->device->id);
616 		break;
617 
618 	case none:
619 		break;
620 	}
621 }
622 
623 /**
624  * fas216_updateptrs - update data pointers after transfer suspended/paused
625  * @info: interface's local pointer to update
626  * @bytes_transferred: number of bytes transferred
627  *
628  * Update data pointers after transfer suspended/paused
629  */
630 static void fas216_updateptrs(FAS216_Info *info, int bytes_transferred)
631 {
632 	struct scsi_pointer *SCp = &info->scsi.SCp;
633 
634 	fas216_checkmagic(info);
635 
636 	BUG_ON(bytes_transferred < 0);
637 
638 	SCp->phase -= bytes_transferred;
639 
640 	while (bytes_transferred != 0) {
641 		if (SCp->this_residual > bytes_transferred)
642 			break;
643 		/*
644 		 * We have used up this buffer.  Move on to the
645 		 * next buffer.
646 		 */
647 		bytes_transferred -= SCp->this_residual;
648 		if (!next_SCp(SCp) && bytes_transferred) {
649 			printk(KERN_WARNING "scsi%d.%c: out of buffers\n",
650 				info->host->host_no, '0' + info->SCpnt->device->id);
651 			return;
652 		}
653 	}
654 
655 	SCp->this_residual -= bytes_transferred;
656 	if (SCp->this_residual)
657 		SCp->ptr += bytes_transferred;
658 	else
659 		SCp->ptr = NULL;
660 }
661 
662 /**
663  * fas216_pio - transfer data off of/on to card using programmed IO
664  * @info: interface to transfer data to/from
665  * @direction: direction to transfer data (DMA_OUT/DMA_IN)
666  *
667  * Transfer data off of/on to card using programmed IO.
668  * Notes: this is incredibly slow.
669  */
670 static void fas216_pio(FAS216_Info *info, fasdmadir_t direction)
671 {
672 	struct scsi_pointer *SCp = &info->scsi.SCp;
673 
674 	fas216_checkmagic(info);
675 
676 	if (direction == DMA_OUT)
677 		fas216_writeb(info, REG_FF, get_next_SCp_byte(SCp));
678 	else
679 		put_next_SCp_byte(SCp, fas216_readb(info, REG_FF));
680 
681 	if (SCp->this_residual == 0)
682 		next_SCp(SCp);
683 }
684 
685 static void fas216_set_stc(FAS216_Info *info, unsigned int length)
686 {
687 	fas216_writeb(info, REG_STCL, length);
688 	fas216_writeb(info, REG_STCM, length >> 8);
689 	fas216_writeb(info, REG_STCH, length >> 16);
690 }
691 
692 static unsigned int fas216_get_ctc(FAS216_Info *info)
693 {
694 	return fas216_readb(info, REG_CTCL) +
695 	       (fas216_readb(info, REG_CTCM) << 8) +
696 	       (fas216_readb(info, REG_CTCH) << 16);
697 }
698 
699 /**
700  * fas216_cleanuptransfer - clean up after a transfer has completed.
701  * @info: interface to clean up
702  *
703  * Update the data pointers according to the number of bytes transferred
704  * on the SCSI bus.
705  */
706 static void fas216_cleanuptransfer(FAS216_Info *info)
707 {
708 	unsigned long total, residual, fifo;
709 	fasdmatype_t dmatype = info->dma.transfer_type;
710 
711 	info->dma.transfer_type = fasdma_none;
712 
713 	/*
714 	 * PIO transfers do not need to be cleaned up.
715 	 */
716 	if (dmatype == fasdma_pio || dmatype == fasdma_none)
717 		return;
718 
719 	if (dmatype == fasdma_real_all)
720 		total = info->scsi.SCp.phase;
721 	else
722 		total = info->scsi.SCp.this_residual;
723 
724 	residual = fas216_get_ctc(info);
725 
726 	fifo = fas216_readb(info, REG_CFIS) & CFIS_CF;
727 
728 	fas216_log(info, LOG_BUFFER, "cleaning up from previous "
729 		   "transfer: length 0x%06x, residual 0x%x, fifo %d",
730 		   total, residual, fifo);
731 
732 	/*
733 	 * If we were performing Data-Out, the transfer counter
734 	 * counts down each time a byte is transferred by the
735 	 * host to the FIFO.  This means we must include the
736 	 * bytes left in the FIFO from the transfer counter.
737 	 */
738 	if (info->scsi.phase == PHASE_DATAOUT)
739 		residual += fifo;
740 
741 	fas216_updateptrs(info, total - residual);
742 }
743 
744 /**
745  * fas216_transfer - Perform a DMA/PIO transfer off of/on to card
746  * @info: interface from which device disconnected from
747  *
748  * Start a DMA/PIO transfer off of/on to card
749  */
750 static void fas216_transfer(FAS216_Info *info)
751 {
752 	fasdmadir_t direction;
753 	fasdmatype_t dmatype;
754 
755 	fas216_log(info, LOG_BUFFER,
756 		   "starttransfer: buffer %p length 0x%06x reqlen 0x%06x",
757 		   info->scsi.SCp.ptr, info->scsi.SCp.this_residual,
758 		   info->scsi.SCp.phase);
759 
760 	if (!info->scsi.SCp.ptr) {
761 		fas216_log(info, LOG_ERROR, "null buffer passed to "
762 			   "fas216_starttransfer");
763 		print_SCp(&info->scsi.SCp, "SCp: ", "\n");
764 		print_SCp(arm_scsi_pointer(info->SCpnt), "Cmnd SCp: ", "\n");
765 		return;
766 	}
767 
768 	/*
769 	 * If we have a synchronous transfer agreement in effect, we must
770 	 * use DMA mode.  If we are using asynchronous transfers, we may
771 	 * use DMA mode or PIO mode.
772 	 */
773 	if (info->device[info->SCpnt->device->id].sof)
774 		dmatype = fasdma_real_all;
775 	else
776 		dmatype = fasdma_pio;
777 
778 	if (info->scsi.phase == PHASE_DATAOUT)
779 		direction = DMA_OUT;
780 	else
781 		direction = DMA_IN;
782 
783 	if (info->dma.setup)
784 		dmatype = info->dma.setup(info->host, &info->scsi.SCp,
785 					  direction, dmatype);
786 	info->dma.transfer_type = dmatype;
787 
788 	if (dmatype == fasdma_real_all)
789 		fas216_set_stc(info, info->scsi.SCp.phase);
790 	else
791 		fas216_set_stc(info, info->scsi.SCp.this_residual);
792 
793 	switch (dmatype) {
794 	case fasdma_pio:
795 		fas216_log(info, LOG_BUFFER, "PIO transfer");
796 		fas216_writeb(info, REG_SOF, 0);
797 		fas216_writeb(info, REG_STP, info->scsi.async_stp);
798 		fas216_cmd(info, CMD_TRANSFERINFO);
799 		fas216_pio(info, direction);
800 		break;
801 
802 	case fasdma_pseudo:
803 		fas216_log(info, LOG_BUFFER, "pseudo transfer");
804 		fas216_cmd(info, CMD_TRANSFERINFO | CMD_WITHDMA);
805 		info->dma.pseudo(info->host, &info->scsi.SCp,
806 				 direction, info->SCpnt->transfersize);
807 		break;
808 
809 	case fasdma_real_block:
810 		fas216_log(info, LOG_BUFFER, "block dma transfer");
811 		fas216_cmd(info, CMD_TRANSFERINFO | CMD_WITHDMA);
812 		break;
813 
814 	case fasdma_real_all:
815 		fas216_log(info, LOG_BUFFER, "total dma transfer");
816 		fas216_cmd(info, CMD_TRANSFERINFO | CMD_WITHDMA);
817 		break;
818 
819 	default:
820 		fas216_log(info, LOG_BUFFER | LOG_ERROR,
821 			   "invalid FAS216 DMA type");
822 		break;
823 	}
824 }
825 
826 /**
827  * fas216_stoptransfer - Stop a DMA transfer onto / off of the card
828  * @info: interface from which device disconnected from
829  *
830  * Called when we switch away from DATA IN or DATA OUT phases.
831  */
832 static void fas216_stoptransfer(FAS216_Info *info)
833 {
834 	fas216_checkmagic(info);
835 
836 	if (info->dma.transfer_type == fasdma_real_all ||
837 	    info->dma.transfer_type == fasdma_real_block)
838 		info->dma.stop(info->host, &info->scsi.SCp);
839 
840 	fas216_cleanuptransfer(info);
841 
842 	if (info->scsi.phase == PHASE_DATAIN) {
843 		unsigned int fifo;
844 
845 		/*
846 		 * If we were performing Data-In, then the FIFO counter
847 		 * contains the number of bytes not transferred via DMA
848 		 * from the on-board FIFO.  Read them manually.
849 		 */
850 		fifo = fas216_readb(info, REG_CFIS) & CFIS_CF;
851 		while (fifo && info->scsi.SCp.ptr) {
852 			*info->scsi.SCp.ptr = fas216_readb(info, REG_FF);
853 			fas216_updateptrs(info, 1);
854 			fifo--;
855 		}
856 	} else {
857 		/*
858 		 * After a Data-Out phase, there may be unsent
859 		 * bytes left in the FIFO.  Flush them out.
860 		 */
861 		fas216_cmd(info, CMD_FLUSHFIFO);
862 	}
863 }
864 
865 static void fas216_aborttransfer(FAS216_Info *info)
866 {
867 	fas216_checkmagic(info);
868 
869 	if (info->dma.transfer_type == fasdma_real_all ||
870 	    info->dma.transfer_type == fasdma_real_block)
871 		info->dma.stop(info->host, &info->scsi.SCp);
872 
873 	info->dma.transfer_type = fasdma_none;
874 	fas216_cmd(info, CMD_FLUSHFIFO);
875 }
876 
877 static void fas216_kick(FAS216_Info *info);
878 
879 /**
880  * fas216_disconnected_intr - handle device disconnection
881  * @info: interface from which device disconnected from
882  *
883  * Handle device disconnection
884  */
885 static void fas216_disconnect_intr(FAS216_Info *info)
886 {
887 	unsigned long flags;
888 
889 	fas216_checkmagic(info);
890 
891 	fas216_log(info, LOG_CONNECT, "disconnect phase=%02x",
892 		   info->scsi.phase);
893 
894 	msgqueue_flush(&info->scsi.msgs);
895 
896 	switch (info->scsi.phase) {
897 	case PHASE_SELECTION:			/* while selecting - no target		*/
898 	case PHASE_SELSTEPS:
899 		fas216_done(info, DID_NO_CONNECT);
900 		break;
901 
902 	case PHASE_MSGIN_DISCONNECT:		/* message in - disconnecting		*/
903 		info->scsi.disconnectable = 1;
904 		info->scsi.phase = PHASE_IDLE;
905 		info->stats.disconnects += 1;
906 		spin_lock_irqsave(&info->host_lock, flags);
907 		if (info->scsi.phase == PHASE_IDLE)
908 			fas216_kick(info);
909 		spin_unlock_irqrestore(&info->host_lock, flags);
910 		break;
911 
912 	case PHASE_DONE:			/* at end of command - complete		*/
913 		fas216_done(info, DID_OK);
914 		break;
915 
916 	case PHASE_MSGOUT:			/* message out - possible ABORT message	*/
917 		if (fas216_get_last_msg(info, info->scsi.msgin_fifo) == ABORT) {
918 			info->scsi.aborting = 0;
919 			fas216_done(info, DID_ABORT);
920 			break;
921 		}
922 		fallthrough;
923 
924 	default:				/* huh?					*/
925 		printk(KERN_ERR "scsi%d.%c: unexpected disconnect in phase %s\n",
926 			info->host->host_no, fas216_target(info), fas216_drv_phase(info));
927 		print_debug_list();
928 		fas216_stoptransfer(info);
929 		fas216_done(info, DID_ERROR);
930 		break;
931 	}
932 }
933 
934 /**
935  * fas216_reselected_intr - start reconnection of a device
936  * @info: interface which was reselected
937  *
938  * Start reconnection of a device
939  */
940 static void
941 fas216_reselected_intr(FAS216_Info *info)
942 {
943 	unsigned int cfis, i;
944 	unsigned char msg[4];
945 	unsigned char target, lun, tag;
946 
947 	fas216_checkmagic(info);
948 
949 	WARN_ON(info->scsi.phase == PHASE_SELECTION ||
950 		info->scsi.phase == PHASE_SELSTEPS);
951 
952 	cfis = fas216_readb(info, REG_CFIS);
953 
954 	fas216_log(info, LOG_CONNECT, "reconnect phase=%02x cfis=%02x",
955 		   info->scsi.phase, cfis);
956 
957 	cfis &= CFIS_CF;
958 
959 	if (cfis < 2 || cfis > 4) {
960 		printk(KERN_ERR "scsi%d.H: incorrect number of bytes after reselect\n",
961 			info->host->host_no);
962 		goto bad_message;
963 	}
964 
965 	for (i = 0; i < cfis; i++)
966 		msg[i] = fas216_readb(info, REG_FF);
967 
968 	if (!(msg[0] & (1 << info->host->this_id)) ||
969 	    !(msg[1] & 0x80))
970 		goto initiator_error;
971 
972 	target = msg[0] & ~(1 << info->host->this_id);
973 	target = ffs(target) - 1;
974 	lun = msg[1] & 7;
975 	tag = 0;
976 
977 	if (cfis >= 3) {
978 		if (msg[2] != SIMPLE_QUEUE_TAG)
979 			goto initiator_error;
980 
981 		tag = msg[3];
982 	}
983 
984 	/* set up for synchronous transfers */
985 	fas216_writeb(info, REG_SDID, target);
986 	fas216_set_sync(info, target);
987 	msgqueue_flush(&info->scsi.msgs);
988 
989 	fas216_log(info, LOG_CONNECT, "Reconnected: target %1x lun %1x tag %02x",
990 		   target, lun, tag);
991 
992 	if (info->scsi.disconnectable && info->SCpnt) {
993 		info->scsi.disconnectable = 0;
994 		if (info->SCpnt->device->id  == target &&
995 		    info->SCpnt->device->lun == lun &&
996 		    scsi_cmd_to_rq(info->SCpnt)->tag == tag) {
997 			fas216_log(info, LOG_CONNECT, "reconnected previously executing command");
998 		} else {
999 			queue_add_cmd_tail(&info->queues.disconnected, info->SCpnt);
1000 			fas216_log(info, LOG_CONNECT, "had to move command to disconnected queue");
1001 			info->SCpnt = NULL;
1002 		}
1003 	}
1004 	if (!info->SCpnt) {
1005 		info->SCpnt = queue_remove_tgtluntag(&info->queues.disconnected,
1006 					target, lun, tag);
1007 		fas216_log(info, LOG_CONNECT, "had to get command");
1008 	}
1009 
1010 	if (info->SCpnt) {
1011 		/*
1012 		 * Restore data pointer from SAVED data pointer
1013 		 */
1014 		info->scsi.SCp = *arm_scsi_pointer(info->SCpnt);
1015 
1016 		fas216_log(info, LOG_CONNECT, "data pointers: [%p, %X]",
1017 			info->scsi.SCp.ptr, info->scsi.SCp.this_residual);
1018 		info->scsi.phase = PHASE_MSGIN;
1019 	} else {
1020 		/*
1021 		 * Our command structure not found - abort the
1022 		 * command on the target.  Since we have no
1023 		 * record of this command, we can't send
1024 		 * an INITIATOR DETECTED ERROR message.
1025 		 */
1026 		fas216_cmd(info, CMD_SETATN);
1027 
1028 #if 0
1029 		if (tag)
1030 			msgqueue_addmsg(&info->scsi.msgs, 2, ABORT_TAG, tag);
1031 		else
1032 #endif
1033 			msgqueue_addmsg(&info->scsi.msgs, 1, ABORT);
1034 		info->scsi.phase = PHASE_MSGOUT_EXPECT;
1035 		info->scsi.aborting = 1;
1036 	}
1037 
1038 	fas216_cmd(info, CMD_MSGACCEPTED);
1039 	return;
1040 
1041  initiator_error:
1042 	printk(KERN_ERR "scsi%d.H: error during reselection: bytes",
1043 		info->host->host_no);
1044 	for (i = 0; i < cfis; i++)
1045 		printk(" %02x", msg[i]);
1046 	printk("\n");
1047  bad_message:
1048 	fas216_cmd(info, CMD_SETATN);
1049 	msgqueue_flush(&info->scsi.msgs);
1050 	msgqueue_addmsg(&info->scsi.msgs, 1, INITIATOR_ERROR);
1051 	info->scsi.phase = PHASE_MSGOUT_EXPECT;
1052 	fas216_cmd(info, CMD_MSGACCEPTED);
1053 }
1054 
1055 static void fas216_parse_message(FAS216_Info *info, unsigned char *message, int msglen)
1056 {
1057 	struct scsi_pointer *scsi_pointer;
1058 	int i;
1059 
1060 	switch (message[0]) {
1061 	case COMMAND_COMPLETE:
1062 		if (msglen != 1)
1063 			goto unrecognised;
1064 
1065 		printk(KERN_ERR "scsi%d.%c: command complete with no "
1066 			"status in MESSAGE_IN?\n",
1067 			info->host->host_no, fas216_target(info));
1068 		break;
1069 
1070 	case SAVE_POINTERS:
1071 		if (msglen != 1)
1072 			goto unrecognised;
1073 
1074 		/*
1075 		 * Save current data pointer to SAVED data pointer
1076 		 * SCSI II standard says that we must not acknowledge
1077 		 * this until we have really saved pointers.
1078 		 * NOTE: we DO NOT save the command nor status pointers
1079 		 * as required by the SCSI II standard.  These always
1080 		 * point to the start of their respective areas.
1081 		 */
1082 		scsi_pointer = arm_scsi_pointer(info->SCpnt);
1083 		*scsi_pointer = info->scsi.SCp;
1084 		scsi_pointer->sent_command = 0;
1085 		fas216_log(info, LOG_CONNECT | LOG_MESSAGES | LOG_BUFFER,
1086 			"save data pointers: [%p, %X]",
1087 			info->scsi.SCp.ptr, info->scsi.SCp.this_residual);
1088 		break;
1089 
1090 	case RESTORE_POINTERS:
1091 		if (msglen != 1)
1092 			goto unrecognised;
1093 
1094 		/*
1095 		 * Restore current data pointer from SAVED data pointer
1096 		 */
1097 		info->scsi.SCp = *arm_scsi_pointer(info->SCpnt);
1098 		fas216_log(info, LOG_CONNECT | LOG_MESSAGES | LOG_BUFFER,
1099 			"restore data pointers: [%p, 0x%x]",
1100 			info->scsi.SCp.ptr, info->scsi.SCp.this_residual);
1101 		break;
1102 
1103 	case DISCONNECT:
1104 		if (msglen != 1)
1105 			goto unrecognised;
1106 
1107 		info->scsi.phase = PHASE_MSGIN_DISCONNECT;
1108 		break;
1109 
1110 	case MESSAGE_REJECT:
1111 		if (msglen != 1)
1112 			goto unrecognised;
1113 
1114 		switch (fas216_get_last_msg(info, info->scsi.msgin_fifo)) {
1115 		case EXTENDED_MESSAGE | EXTENDED_SDTR << 8:
1116 			fas216_handlesync(info, message);
1117 			break;
1118 
1119 		default:
1120 			fas216_log(info, 0, "reject, last message 0x%04x",
1121 				fas216_get_last_msg(info, info->scsi.msgin_fifo));
1122 		}
1123 		break;
1124 
1125 	case NOP:
1126 		break;
1127 
1128 	case EXTENDED_MESSAGE:
1129 		if (msglen < 3)
1130 			goto unrecognised;
1131 
1132 		switch (message[2]) {
1133 		case EXTENDED_SDTR:	/* Sync transfer negotiation request/reply */
1134 			fas216_handlesync(info, message);
1135 			break;
1136 
1137 		default:
1138 			goto unrecognised;
1139 		}
1140 		break;
1141 
1142 	default:
1143 		goto unrecognised;
1144 	}
1145 	return;
1146 
1147 unrecognised:
1148 	fas216_log(info, 0, "unrecognised message, rejecting");
1149 	printk("scsi%d.%c: message was", info->host->host_no, fas216_target(info));
1150 	for (i = 0; i < msglen; i++)
1151 		printk("%s%02X", i & 31 ? " " : "\n  ", message[i]);
1152 	printk("\n");
1153 
1154 	/*
1155 	 * Something strange seems to be happening here -
1156 	 * I can't use SETATN since the chip gives me an
1157 	 * invalid command interrupt when I do.  Weird.
1158 	 */
1159 fas216_cmd(info, CMD_NOP);
1160 fas216_dumpstate(info);
1161 	fas216_cmd(info, CMD_SETATN);
1162 	msgqueue_flush(&info->scsi.msgs);
1163 	msgqueue_addmsg(&info->scsi.msgs, 1, MESSAGE_REJECT);
1164 	info->scsi.phase = PHASE_MSGOUT_EXPECT;
1165 fas216_dumpstate(info);
1166 }
1167 
1168 static int fas216_wait_cmd(FAS216_Info *info, int cmd)
1169 {
1170 	int tout;
1171 	int stat;
1172 
1173 	fas216_cmd(info, cmd);
1174 
1175 	for (tout = 1000; tout; tout -= 1) {
1176 		stat = fas216_readb(info, REG_STAT);
1177 		if (stat & (STAT_INT|STAT_PARITYERROR))
1178 			break;
1179 		udelay(1);
1180 	}
1181 
1182 	return stat;
1183 }
1184 
1185 static int fas216_get_msg_byte(FAS216_Info *info)
1186 {
1187 	unsigned int stat = fas216_wait_cmd(info, CMD_MSGACCEPTED);
1188 
1189 	if ((stat & STAT_INT) == 0)
1190 		goto timedout;
1191 
1192 	if ((stat & STAT_BUSMASK) != STAT_MESGIN)
1193 		goto unexpected_phase_change;
1194 
1195 	fas216_readb(info, REG_INST);
1196 
1197 	stat = fas216_wait_cmd(info, CMD_TRANSFERINFO);
1198 
1199 	if ((stat & STAT_INT) == 0)
1200 		goto timedout;
1201 
1202 	if (stat & STAT_PARITYERROR)
1203 		goto parity_error;
1204 
1205 	if ((stat & STAT_BUSMASK) != STAT_MESGIN)
1206 		goto unexpected_phase_change;
1207 
1208 	fas216_readb(info, REG_INST);
1209 
1210 	return fas216_readb(info, REG_FF);
1211 
1212 timedout:
1213 	fas216_log(info, LOG_ERROR, "timed out waiting for message byte");
1214 	return -1;
1215 
1216 unexpected_phase_change:
1217 	fas216_log(info, LOG_ERROR, "unexpected phase change: status = %02x", stat);
1218 	return -2;
1219 
1220 parity_error:
1221 	fas216_log(info, LOG_ERROR, "parity error during message in phase");
1222 	return -3;
1223 }
1224 
1225 /**
1226  * fas216_message - handle a function done interrupt from FAS216 chip
1227  * @info: interface which caused function done interrupt
1228  *
1229  * Handle a function done interrupt from FAS216 chip
1230  */
1231 static void fas216_message(FAS216_Info *info)
1232 {
1233 	unsigned char *message = info->scsi.message;
1234 	unsigned int msglen = 1;
1235 	int msgbyte = 0;
1236 
1237 	fas216_checkmagic(info);
1238 
1239 	message[0] = fas216_readb(info, REG_FF);
1240 
1241 	if (message[0] == EXTENDED_MESSAGE) {
1242 		msgbyte = fas216_get_msg_byte(info);
1243 
1244 		if (msgbyte >= 0) {
1245 			message[1] = msgbyte;
1246 
1247 			for (msglen = 2; msglen < message[1] + 2; msglen++) {
1248 				msgbyte = fas216_get_msg_byte(info);
1249 
1250 				if (msgbyte >= 0)
1251 					message[msglen] = msgbyte;
1252 				else
1253 					break;
1254 			}
1255 		}
1256 	}
1257 
1258 	if (msgbyte == -3)
1259 		goto parity_error;
1260 
1261 #ifdef DEBUG_MESSAGES
1262 	{
1263 		int i;
1264 
1265 		printk("scsi%d.%c: message in: ",
1266 			info->host->host_no, fas216_target(info));
1267 		for (i = 0; i < msglen; i++)
1268 			printk("%02X ", message[i]);
1269 		printk("\n");
1270 	}
1271 #endif
1272 
1273 	fas216_parse_message(info, message, msglen);
1274 	fas216_cmd(info, CMD_MSGACCEPTED);
1275 	return;
1276 
1277 parity_error:
1278 	fas216_cmd(info, CMD_SETATN);
1279 	msgqueue_flush(&info->scsi.msgs);
1280 	msgqueue_addmsg(&info->scsi.msgs, 1, MSG_PARITY_ERROR);
1281 	info->scsi.phase = PHASE_MSGOUT_EXPECT;
1282 	fas216_cmd(info, CMD_MSGACCEPTED);
1283 	return;
1284 }
1285 
1286 /**
1287  * fas216_send_command - send command after all message bytes have been sent
1288  * @info: interface which caused bus service
1289  *
1290  * Send a command to a target after all message bytes have been sent
1291  */
1292 static void fas216_send_command(FAS216_Info *info)
1293 {
1294 	int i;
1295 
1296 	fas216_checkmagic(info);
1297 
1298 	fas216_cmd(info, CMD_NOP|CMD_WITHDMA);
1299 	fas216_cmd(info, CMD_FLUSHFIFO);
1300 
1301 	/* load command */
1302 	for (i = info->scsi.SCp.sent_command; i < info->SCpnt->cmd_len; i++)
1303 		fas216_writeb(info, REG_FF, info->SCpnt->cmnd[i]);
1304 
1305 	fas216_cmd(info, CMD_TRANSFERINFO);
1306 
1307 	info->scsi.phase = PHASE_COMMAND;
1308 }
1309 
1310 /**
1311  * fas216_send_messageout - handle bus service to send a message
1312  * @info: interface which caused bus service
1313  *
1314  * Handle bus service to send a message.
1315  * Note: We do not allow the device to change the data direction!
1316  */
1317 static void fas216_send_messageout(FAS216_Info *info, int start)
1318 {
1319 	unsigned int tot_msglen = msgqueue_msglength(&info->scsi.msgs);
1320 
1321 	fas216_checkmagic(info);
1322 
1323 	fas216_cmd(info, CMD_FLUSHFIFO);
1324 
1325 	if (tot_msglen) {
1326 		struct message *msg;
1327 		int msgnr = 0;
1328 
1329 		while ((msg = msgqueue_getmsg(&info->scsi.msgs, msgnr++)) != NULL) {
1330 			int i;
1331 
1332 			for (i = start; i < msg->length; i++)
1333 				fas216_writeb(info, REG_FF, msg->msg[i]);
1334 
1335 			msg->fifo = tot_msglen - (fas216_readb(info, REG_CFIS) & CFIS_CF);
1336 			start = 0;
1337 		}
1338 	} else
1339 		fas216_writeb(info, REG_FF, NOP);
1340 
1341 	fas216_cmd(info, CMD_TRANSFERINFO);
1342 
1343 	info->scsi.phase = PHASE_MSGOUT;
1344 }
1345 
1346 /**
1347  * fas216_busservice_intr - handle bus service interrupt from FAS216 chip
1348  * @info: interface which caused bus service interrupt
1349  * @stat: Status register contents
1350  * @is: SCSI Status register contents
1351  *
1352  * Handle a bus service interrupt from FAS216 chip
1353  */
1354 static void fas216_busservice_intr(FAS216_Info *info, unsigned int stat, unsigned int is)
1355 {
1356 	fas216_checkmagic(info);
1357 
1358 	fas216_log(info, LOG_BUSSERVICE,
1359 		   "bus service: stat=%02x is=%02x phase=%02x",
1360 		   stat, is, info->scsi.phase);
1361 
1362 	switch (info->scsi.phase) {
1363 	case PHASE_SELECTION:
1364 		if ((is & IS_BITS) != IS_MSGBYTESENT)
1365 			goto bad_is;
1366 		break;
1367 
1368 	case PHASE_SELSTEPS:
1369 		switch (is & IS_BITS) {
1370 		case IS_SELARB:
1371 		case IS_MSGBYTESENT:
1372 			goto bad_is;
1373 
1374 		case IS_NOTCOMMAND:
1375 		case IS_EARLYPHASE:
1376 			if ((stat & STAT_BUSMASK) == STAT_MESGIN)
1377 				break;
1378 			goto bad_is;
1379 
1380 		case IS_COMPLETE:
1381 			break;
1382 		}
1383 		break;
1384 
1385 	default:
1386 		break;
1387 	}
1388 
1389 	fas216_cmd(info, CMD_NOP);
1390 
1391 #define STATE(st,ph) ((ph) << 3 | (st))
1392 	/* This table describes the legal SCSI state transitions,
1393 	 * as described by the SCSI II spec.
1394 	 */
1395 	switch (STATE(stat & STAT_BUSMASK, info->scsi.phase)) {
1396 	case STATE(STAT_DATAIN, PHASE_SELSTEPS):/* Sel w/ steps -> Data In      */
1397 	case STATE(STAT_DATAIN, PHASE_MSGOUT):  /* Message Out  -> Data In      */
1398 	case STATE(STAT_DATAIN, PHASE_COMMAND): /* Command      -> Data In      */
1399 	case STATE(STAT_DATAIN, PHASE_MSGIN):   /* Message In   -> Data In      */
1400 		info->scsi.phase = PHASE_DATAIN;
1401 		fas216_transfer(info);
1402 		return;
1403 
1404 	case STATE(STAT_DATAIN, PHASE_DATAIN):  /* Data In      -> Data In      */
1405 	case STATE(STAT_DATAOUT, PHASE_DATAOUT):/* Data Out     -> Data Out     */
1406 		fas216_cleanuptransfer(info);
1407 		fas216_transfer(info);
1408 		return;
1409 
1410 	case STATE(STAT_DATAOUT, PHASE_SELSTEPS):/* Sel w/ steps-> Data Out     */
1411 	case STATE(STAT_DATAOUT, PHASE_MSGOUT): /* Message Out  -> Data Out     */
1412 	case STATE(STAT_DATAOUT, PHASE_COMMAND):/* Command      -> Data Out     */
1413 	case STATE(STAT_DATAOUT, PHASE_MSGIN):  /* Message In   -> Data Out     */
1414 		fas216_cmd(info, CMD_FLUSHFIFO);
1415 		info->scsi.phase = PHASE_DATAOUT;
1416 		fas216_transfer(info);
1417 		return;
1418 
1419 	case STATE(STAT_STATUS, PHASE_DATAOUT): /* Data Out     -> Status       */
1420 	case STATE(STAT_STATUS, PHASE_DATAIN):  /* Data In      -> Status       */
1421 		fas216_stoptransfer(info);
1422 		fallthrough;
1423 
1424 	case STATE(STAT_STATUS, PHASE_SELSTEPS):/* Sel w/ steps -> Status       */
1425 	case STATE(STAT_STATUS, PHASE_MSGOUT):  /* Message Out  -> Status       */
1426 	case STATE(STAT_STATUS, PHASE_COMMAND): /* Command      -> Status       */
1427 	case STATE(STAT_STATUS, PHASE_MSGIN):   /* Message In   -> Status       */
1428 		fas216_cmd(info, CMD_INITCMDCOMPLETE);
1429 		info->scsi.phase = PHASE_STATUS;
1430 		return;
1431 
1432 	case STATE(STAT_MESGIN, PHASE_DATAOUT): /* Data Out     -> Message In   */
1433 	case STATE(STAT_MESGIN, PHASE_DATAIN):  /* Data In      -> Message In   */
1434 		fas216_stoptransfer(info);
1435 		fallthrough;
1436 
1437 	case STATE(STAT_MESGIN, PHASE_COMMAND):	/* Command	-> Message In	*/
1438 	case STATE(STAT_MESGIN, PHASE_SELSTEPS):/* Sel w/ steps -> Message In   */
1439 	case STATE(STAT_MESGIN, PHASE_MSGOUT):  /* Message Out  -> Message In   */
1440 		info->scsi.msgin_fifo = fas216_readb(info, REG_CFIS) & CFIS_CF;
1441 		fas216_cmd(info, CMD_FLUSHFIFO);
1442 		fas216_cmd(info, CMD_TRANSFERINFO);
1443 		info->scsi.phase = PHASE_MSGIN;
1444 		return;
1445 
1446 	case STATE(STAT_MESGIN, PHASE_MSGIN):
1447 		info->scsi.msgin_fifo = fas216_readb(info, REG_CFIS) & CFIS_CF;
1448 		fas216_cmd(info, CMD_TRANSFERINFO);
1449 		return;
1450 
1451 	case STATE(STAT_COMMAND, PHASE_MSGOUT): /* Message Out  -> Command      */
1452 	case STATE(STAT_COMMAND, PHASE_MSGIN):  /* Message In   -> Command      */
1453 		fas216_send_command(info);
1454 		info->scsi.phase = PHASE_COMMAND;
1455 		return;
1456 
1457 
1458 	/*
1459 	 * Selection    -> Message Out
1460 	 */
1461 	case STATE(STAT_MESGOUT, PHASE_SELECTION):
1462 		fas216_send_messageout(info, 1);
1463 		return;
1464 
1465 	/*
1466 	 * Message Out  -> Message Out
1467 	 */
1468 	case STATE(STAT_MESGOUT, PHASE_SELSTEPS):
1469 	case STATE(STAT_MESGOUT, PHASE_MSGOUT):
1470 		/*
1471 		 * If we get another message out phase, this usually
1472 		 * means some parity error occurred.  Resend complete
1473 		 * set of messages.  If we have more than one byte to
1474 		 * send, we need to assert ATN again.
1475 		 */
1476 		if (info->device[info->SCpnt->device->id].parity_check) {
1477 			/*
1478 			 * We were testing... good, the device
1479 			 * supports parity checking.
1480 			 */
1481 			info->device[info->SCpnt->device->id].parity_check = 0;
1482 			info->device[info->SCpnt->device->id].parity_enabled = 1;
1483 			fas216_writeb(info, REG_CNTL1, info->scsi.cfg[0]);
1484 		}
1485 
1486 		if (msgqueue_msglength(&info->scsi.msgs) > 1)
1487 			fas216_cmd(info, CMD_SETATN);
1488 		fallthrough;
1489 
1490 	/*
1491 	 * Any          -> Message Out
1492 	 */
1493 	case STATE(STAT_MESGOUT, PHASE_MSGOUT_EXPECT):
1494 		fas216_send_messageout(info, 0);
1495 		return;
1496 
1497 	/* Error recovery rules.
1498 	 *   These either attempt to abort or retry the operation.
1499 	 * TODO: we need more of these
1500 	 */
1501 	case STATE(STAT_COMMAND, PHASE_COMMAND):/* Command      -> Command      */
1502 		/* error - we've sent out all the command bytes
1503 		 * we have.
1504 		 * NOTE: we need SAVE DATA POINTERS/RESTORE DATA POINTERS
1505 		 * to include the command bytes sent for this to work
1506 		 * correctly.
1507 		 */
1508 		printk(KERN_ERR "scsi%d.%c: "
1509 			"target trying to receive more command bytes\n",
1510 			info->host->host_no, fas216_target(info));
1511 		fas216_cmd(info, CMD_SETATN);
1512 		fas216_set_stc(info, 15);
1513 		fas216_cmd(info, CMD_PADBYTES | CMD_WITHDMA);
1514 		msgqueue_flush(&info->scsi.msgs);
1515 		msgqueue_addmsg(&info->scsi.msgs, 1, INITIATOR_ERROR);
1516 		info->scsi.phase = PHASE_MSGOUT_EXPECT;
1517 		return;
1518 	}
1519 
1520 	if (info->scsi.phase == PHASE_MSGIN_DISCONNECT) {
1521 		printk(KERN_ERR "scsi%d.%c: disconnect message received, but bus service %s?\n",
1522 			info->host->host_no, fas216_target(info),
1523 			fas216_bus_phase(stat));
1524 		msgqueue_flush(&info->scsi.msgs);
1525 		fas216_cmd(info, CMD_SETATN);
1526 		msgqueue_addmsg(&info->scsi.msgs, 1, INITIATOR_ERROR);
1527 		info->scsi.phase = PHASE_MSGOUT_EXPECT;
1528 		info->scsi.aborting = 1;
1529 		fas216_cmd(info, CMD_TRANSFERINFO);
1530 		return;
1531 	}
1532 	printk(KERN_ERR "scsi%d.%c: bus phase %s after %s?\n",
1533 		info->host->host_no, fas216_target(info),
1534 		fas216_bus_phase(stat),
1535 		fas216_drv_phase(info));
1536 	print_debug_list();
1537 	return;
1538 
1539 bad_is:
1540 	fas216_log(info, 0, "bus service at step %d?", is & IS_BITS);
1541 	fas216_dumpstate(info);
1542 	print_debug_list();
1543 
1544 	fas216_done(info, DID_ERROR);
1545 }
1546 
1547 /**
1548  * fas216_funcdone_intr - handle a function done interrupt from FAS216 chip
1549  * @info: interface which caused function done interrupt
1550  * @stat: Status register contents
1551  * @is: SCSI Status register contents
1552  *
1553  * Handle a function done interrupt from FAS216 chip
1554  */
1555 static void fas216_funcdone_intr(FAS216_Info *info, unsigned int stat, unsigned int is)
1556 {
1557 	unsigned int fifo_len = fas216_readb(info, REG_CFIS) & CFIS_CF;
1558 
1559 	fas216_checkmagic(info);
1560 
1561 	fas216_log(info, LOG_FUNCTIONDONE,
1562 		   "function done: stat=%02x is=%02x phase=%02x",
1563 		   stat, is, info->scsi.phase);
1564 
1565 	switch (info->scsi.phase) {
1566 	case PHASE_STATUS:			/* status phase - read status and msg	*/
1567 		if (fifo_len != 2) {
1568 			fas216_log(info, 0, "odd number of bytes in FIFO: %d", fifo_len);
1569 		}
1570 		/*
1571 		 * Read status then message byte.
1572 		 */
1573 		info->scsi.SCp.Status = fas216_readb(info, REG_FF);
1574 		info->scsi.SCp.Message = fas216_readb(info, REG_FF);
1575 		info->scsi.phase = PHASE_DONE;
1576 		fas216_cmd(info, CMD_MSGACCEPTED);
1577 		break;
1578 
1579 	case PHASE_IDLE:
1580 	case PHASE_SELECTION:
1581 	case PHASE_SELSTEPS:
1582 		break;
1583 
1584 	case PHASE_MSGIN:			/* message in phase			*/
1585 		if ((stat & STAT_BUSMASK) == STAT_MESGIN) {
1586 			info->scsi.msgin_fifo = fifo_len;
1587 			fas216_message(info);
1588 			break;
1589 		}
1590 		fallthrough;
1591 
1592 	default:
1593 		fas216_log(info, 0, "internal phase %s for function done?"
1594 			"  What do I do with this?",
1595 			fas216_target(info), fas216_drv_phase(info));
1596 	}
1597 }
1598 
1599 static void fas216_bus_reset(FAS216_Info *info)
1600 {
1601 	neg_t sync_state;
1602 	int i;
1603 
1604 	msgqueue_flush(&info->scsi.msgs);
1605 
1606 	sync_state = neg_invalid;
1607 
1608 #ifdef SCSI2_SYNC
1609 	if (info->ifcfg.capabilities & (FASCAP_DMA|FASCAP_PSEUDODMA))
1610 		sync_state = neg_wait;
1611 #endif
1612 
1613 	info->scsi.phase = PHASE_IDLE;
1614 	info->SCpnt = NULL; /* bug! */
1615 	memset(&info->scsi.SCp, 0, sizeof(info->scsi.SCp));
1616 
1617 	for (i = 0; i < 8; i++) {
1618 		info->device[i].disconnect_ok	= info->ifcfg.disconnect_ok;
1619 		info->device[i].sync_state	= sync_state;
1620 		info->device[i].period		= info->ifcfg.asyncperiod / 4;
1621 		info->device[i].stp		= info->scsi.async_stp;
1622 		info->device[i].sof		= 0;
1623 		info->device[i].wide_xfer	= 0;
1624 	}
1625 
1626 	info->rst_bus_status = 1;
1627 	wake_up(&info->eh_wait);
1628 }
1629 
1630 /**
1631  * fas216_intr - handle interrupts to progress a command
1632  * @info: interface to service
1633  *
1634  * Handle interrupts from the interface to progress a command
1635  */
1636 irqreturn_t fas216_intr(FAS216_Info *info)
1637 {
1638 	unsigned char inst, is, stat;
1639 	int handled = IRQ_NONE;
1640 
1641 	fas216_checkmagic(info);
1642 
1643 	stat = fas216_readb(info, REG_STAT);
1644 	is = fas216_readb(info, REG_IS);
1645 	inst = fas216_readb(info, REG_INST);
1646 
1647 	add_debug_list(stat, is, inst, info->scsi.phase);
1648 
1649 	if (stat & STAT_INT) {
1650 		if (inst & INST_BUSRESET) {
1651 			fas216_log(info, 0, "bus reset detected");
1652 			fas216_bus_reset(info);
1653 			scsi_report_bus_reset(info->host, 0);
1654 		} else if (inst & INST_ILLEGALCMD) {
1655 			fas216_log(info, LOG_ERROR, "illegal command given\n");
1656 			fas216_dumpstate(info);
1657 			print_debug_list();
1658 		} else if (inst & INST_DISCONNECT)
1659 			fas216_disconnect_intr(info);
1660 		else if (inst & INST_RESELECTED)	/* reselected			*/
1661 			fas216_reselected_intr(info);
1662 		else if (inst & INST_BUSSERVICE)	/* bus service request		*/
1663 			fas216_busservice_intr(info, stat, is);
1664 		else if (inst & INST_FUNCDONE)		/* function done		*/
1665 			fas216_funcdone_intr(info, stat, is);
1666 		else
1667 		    	fas216_log(info, 0, "unknown interrupt received:"
1668 				" phase %s inst %02X is %02X stat %02X",
1669 				fas216_drv_phase(info), inst, is, stat);
1670 		handled = IRQ_HANDLED;
1671 	}
1672 	return handled;
1673 }
1674 
1675 static void __fas216_start_command(FAS216_Info *info, struct scsi_cmnd *SCpnt)
1676 {
1677 	int tot_msglen;
1678 
1679 	/* following what the ESP driver says */
1680 	fas216_set_stc(info, 0);
1681 	fas216_cmd(info, CMD_NOP | CMD_WITHDMA);
1682 
1683 	/* flush FIFO */
1684 	fas216_cmd(info, CMD_FLUSHFIFO);
1685 
1686 	/* load bus-id and timeout */
1687 	fas216_writeb(info, REG_SDID, BUSID(SCpnt->device->id));
1688 	fas216_writeb(info, REG_STIM, info->ifcfg.select_timeout);
1689 
1690 	/* synchronous transfers */
1691 	fas216_set_sync(info, SCpnt->device->id);
1692 
1693 	tot_msglen = msgqueue_msglength(&info->scsi.msgs);
1694 
1695 #ifdef DEBUG_MESSAGES
1696 	{
1697 		struct message *msg;
1698 		int msgnr = 0, i;
1699 
1700 		printk("scsi%d.%c: message out: ",
1701 			info->host->host_no, '0' + SCpnt->device->id);
1702 		while ((msg = msgqueue_getmsg(&info->scsi.msgs, msgnr++)) != NULL) {
1703 			printk("{ ");
1704 			for (i = 0; i < msg->length; i++)
1705 				printk("%02x ", msg->msg[i]);
1706 			printk("} ");
1707 		}
1708 		printk("\n");
1709 	}
1710 #endif
1711 
1712 	if (tot_msglen == 1 || tot_msglen == 3) {
1713 		/*
1714 		 * We have an easy message length to send...
1715 		 */
1716 		struct message *msg;
1717 		int msgnr = 0, i;
1718 
1719 		info->scsi.phase = PHASE_SELSTEPS;
1720 
1721 		/* load message bytes */
1722 		while ((msg = msgqueue_getmsg(&info->scsi.msgs, msgnr++)) != NULL) {
1723 			for (i = 0; i < msg->length; i++)
1724 				fas216_writeb(info, REG_FF, msg->msg[i]);
1725 			msg->fifo = tot_msglen - (fas216_readb(info, REG_CFIS) & CFIS_CF);
1726 		}
1727 
1728 		/* load command */
1729 		for (i = 0; i < SCpnt->cmd_len; i++)
1730 			fas216_writeb(info, REG_FF, SCpnt->cmnd[i]);
1731 
1732 		if (tot_msglen == 1)
1733 			fas216_cmd(info, CMD_SELECTATN);
1734 		else
1735 			fas216_cmd(info, CMD_SELECTATN3);
1736 	} else {
1737 		/*
1738 		 * We have an unusual number of message bytes to send.
1739 		 *  Load first byte into fifo, and issue SELECT with ATN and
1740 		 *  stop steps.
1741 		 */
1742 		struct message *msg = msgqueue_getmsg(&info->scsi.msgs, 0);
1743 
1744 		fas216_writeb(info, REG_FF, msg->msg[0]);
1745 		msg->fifo = 1;
1746 
1747 		fas216_cmd(info, CMD_SELECTATNSTOP);
1748 	}
1749 }
1750 
1751 /*
1752  * Decide whether we need to perform a parity test on this device.
1753  * Can also be used to force parity error conditions during initial
1754  * information transfer phase (message out) for test purposes.
1755  */
1756 static int parity_test(FAS216_Info *info, int target)
1757 {
1758 #if 0
1759 	if (target == 3) {
1760 		info->device[target].parity_check = 0;
1761 		return 1;
1762 	}
1763 #endif
1764 	return info->device[target].parity_check;
1765 }
1766 
1767 static void fas216_start_command(FAS216_Info *info, struct scsi_cmnd *SCpnt)
1768 {
1769 	int disconnect_ok;
1770 
1771 	/*
1772 	 * claim host busy
1773 	 */
1774 	info->scsi.phase = PHASE_SELECTION;
1775 	info->scsi.SCp = *arm_scsi_pointer(SCpnt);
1776 	info->SCpnt = SCpnt;
1777 	info->dma.transfer_type = fasdma_none;
1778 
1779 	if (parity_test(info, SCpnt->device->id))
1780 		fas216_writeb(info, REG_CNTL1, info->scsi.cfg[0] | CNTL1_PTE);
1781 	else
1782 		fas216_writeb(info, REG_CNTL1, info->scsi.cfg[0]);
1783 
1784 	/*
1785 	 * Don't allow request sense commands to disconnect.
1786 	 */
1787 	disconnect_ok = SCpnt->cmnd[0] != REQUEST_SENSE &&
1788 			info->device[SCpnt->device->id].disconnect_ok;
1789 
1790 	/*
1791 	 * build outgoing message bytes
1792 	 */
1793 	msgqueue_flush(&info->scsi.msgs);
1794 	msgqueue_addmsg(&info->scsi.msgs, 1, IDENTIFY(disconnect_ok, SCpnt->device->lun));
1795 
1796 	/*
1797 	 * add tag message if required
1798 	 */
1799 	if (SCpnt->device->simple_tags)
1800 		msgqueue_addmsg(&info->scsi.msgs, 2, SIMPLE_QUEUE_TAG,
1801 				scsi_cmd_to_rq(SCpnt)->tag);
1802 
1803 	do {
1804 #ifdef SCSI2_SYNC
1805 		if ((info->device[SCpnt->device->id].sync_state == neg_wait ||
1806 		     info->device[SCpnt->device->id].sync_state == neg_complete) &&
1807 		    (SCpnt->cmnd[0] == REQUEST_SENSE ||
1808 		     SCpnt->cmnd[0] == INQUIRY)) {
1809 			info->device[SCpnt->device->id].sync_state = neg_inprogress;
1810 			msgqueue_addmsg(&info->scsi.msgs, 5,
1811 					EXTENDED_MESSAGE, 3, EXTENDED_SDTR,
1812 					1000 / info->ifcfg.clockrate,
1813 					info->ifcfg.sync_max_depth);
1814 			break;
1815 		}
1816 #endif
1817 	} while (0);
1818 
1819 	__fas216_start_command(info, SCpnt);
1820 }
1821 
1822 static void fas216_allocate_tag(FAS216_Info *info, struct scsi_cmnd *SCpnt)
1823 {
1824 	set_bit(SCpnt->device->id * 8 +
1825 		(u8)(SCpnt->device->lun & 0x7), info->busyluns);
1826 
1827 	info->stats.removes += 1;
1828 	switch (SCpnt->cmnd[0]) {
1829 	case WRITE_6:
1830 	case WRITE_10:
1831 	case WRITE_12:
1832 		info->stats.writes += 1;
1833 		break;
1834 	case READ_6:
1835 	case READ_10:
1836 	case READ_12:
1837 		info->stats.reads += 1;
1838 		break;
1839 	default:
1840 		info->stats.miscs += 1;
1841 		break;
1842 	}
1843 }
1844 
1845 static void fas216_do_bus_device_reset(FAS216_Info *info,
1846 				       struct scsi_cmnd *SCpnt)
1847 {
1848 	struct message *msg;
1849 
1850 	/*
1851 	 * claim host busy
1852 	 */
1853 	info->scsi.phase = PHASE_SELECTION;
1854 	info->scsi.SCp = *arm_scsi_pointer(SCpnt);
1855 	info->SCpnt = SCpnt;
1856 	info->dma.transfer_type = fasdma_none;
1857 
1858 	fas216_log(info, LOG_ERROR, "sending bus device reset");
1859 
1860 	msgqueue_flush(&info->scsi.msgs);
1861 	msgqueue_addmsg(&info->scsi.msgs, 1, BUS_DEVICE_RESET);
1862 
1863 	/* following what the ESP driver says */
1864 	fas216_set_stc(info, 0);
1865 	fas216_cmd(info, CMD_NOP | CMD_WITHDMA);
1866 
1867 	/* flush FIFO */
1868 	fas216_cmd(info, CMD_FLUSHFIFO);
1869 
1870 	/* load bus-id and timeout */
1871 	fas216_writeb(info, REG_SDID, BUSID(SCpnt->device->id));
1872 	fas216_writeb(info, REG_STIM, info->ifcfg.select_timeout);
1873 
1874 	/* synchronous transfers */
1875 	fas216_set_sync(info, SCpnt->device->id);
1876 
1877 	msg = msgqueue_getmsg(&info->scsi.msgs, 0);
1878 
1879 	fas216_writeb(info, REG_FF, BUS_DEVICE_RESET);
1880 	msg->fifo = 1;
1881 
1882 	fas216_cmd(info, CMD_SELECTATNSTOP);
1883 }
1884 
1885 /**
1886  * fas216_kick - kick a command to the interface
1887  * @info: our host interface to kick
1888  *
1889  * Kick a command to the interface, interface should be idle.
1890  * Notes: Interrupts are always disabled!
1891  */
1892 static void fas216_kick(FAS216_Info *info)
1893 {
1894 	struct scsi_cmnd *SCpnt = NULL;
1895 #define TYPE_OTHER	0
1896 #define TYPE_RESET	1
1897 #define TYPE_QUEUE	2
1898 	int where_from = TYPE_OTHER;
1899 
1900 	fas216_checkmagic(info);
1901 
1902 	/*
1903 	 * Obtain the next command to process.
1904 	 */
1905 	do {
1906 		if (info->rstSCpnt) {
1907 			SCpnt = info->rstSCpnt;
1908 			/* don't remove it */
1909 			where_from = TYPE_RESET;
1910 			break;
1911 		}
1912 
1913 		if (info->reqSCpnt) {
1914 			SCpnt = info->reqSCpnt;
1915 			info->reqSCpnt = NULL;
1916 			break;
1917 		}
1918 
1919 		if (info->origSCpnt) {
1920 			SCpnt = info->origSCpnt;
1921 			info->origSCpnt = NULL;
1922 			break;
1923 		}
1924 
1925 		/* retrieve next command */
1926 		if (!SCpnt) {
1927 			SCpnt = queue_remove_exclude(&info->queues.issue,
1928 						     info->busyluns);
1929 			where_from = TYPE_QUEUE;
1930 			break;
1931 		}
1932 	} while (0);
1933 
1934 	if (!SCpnt) {
1935 		/*
1936 		 * no command pending, so enable reselection.
1937 		 */
1938 		fas216_cmd(info, CMD_ENABLESEL);
1939 		return;
1940 	}
1941 
1942 	/*
1943 	 * We're going to start a command, so disable reselection
1944 	 */
1945 	fas216_cmd(info, CMD_DISABLESEL);
1946 
1947 	if (info->scsi.disconnectable && info->SCpnt) {
1948 		fas216_log(info, LOG_CONNECT,
1949 			"moved command for %d to disconnected queue",
1950 			info->SCpnt->device->id);
1951 		queue_add_cmd_tail(&info->queues.disconnected, info->SCpnt);
1952 		info->scsi.disconnectable = 0;
1953 		info->SCpnt = NULL;
1954 	}
1955 
1956 	fas216_log_command(info, LOG_CONNECT | LOG_MESSAGES, SCpnt,
1957 			   "starting");
1958 
1959 	switch (where_from) {
1960 	case TYPE_QUEUE:
1961 		fas216_allocate_tag(info, SCpnt);
1962 		fallthrough;
1963 	case TYPE_OTHER:
1964 		fas216_start_command(info, SCpnt);
1965 		break;
1966 	case TYPE_RESET:
1967 		fas216_do_bus_device_reset(info, SCpnt);
1968 		break;
1969 	}
1970 
1971 	fas216_log(info, LOG_CONNECT, "select: data pointers [%p, %X]",
1972 		info->scsi.SCp.ptr, info->scsi.SCp.this_residual);
1973 
1974 	/*
1975 	 * should now get either DISCONNECT or
1976 	 * (FUNCTION DONE with BUS SERVICE) interrupt
1977 	 */
1978 }
1979 
1980 /*
1981  * Clean up from issuing a BUS DEVICE RESET message to a device.
1982  */
1983 static void fas216_devicereset_done(FAS216_Info *info, struct scsi_cmnd *SCpnt,
1984 				    unsigned int result)
1985 {
1986 	fas216_log(info, LOG_ERROR, "fas216 device reset complete");
1987 
1988 	info->rstSCpnt = NULL;
1989 	info->rst_dev_status = 1;
1990 	wake_up(&info->eh_wait);
1991 }
1992 
1993 /**
1994  * fas216_rq_sns_done - Finish processing automatic request sense command
1995  * @info: interface that completed
1996  * @SCpnt: command that completed
1997  * @result: driver byte of result
1998  *
1999  * Finish processing automatic request sense command
2000  */
2001 static void fas216_rq_sns_done(FAS216_Info *info, struct scsi_cmnd *SCpnt,
2002 			       unsigned int result)
2003 {
2004 	struct scsi_pointer *scsi_pointer = arm_scsi_pointer(SCpnt);
2005 
2006 	fas216_log_target(info, LOG_CONNECT, SCpnt->device->id,
2007 		   "request sense complete, result=0x%04x%02x%02x",
2008 		   result, scsi_pointer->Message, scsi_pointer->Status);
2009 
2010 	if (result != DID_OK || scsi_pointer->Status != SAM_STAT_GOOD)
2011 		/*
2012 		 * Something went wrong.  Make sure that we don't
2013 		 * have valid data in the sense buffer that could
2014 		 * confuse the higher levels.
2015 		 */
2016 		memset(SCpnt->sense_buffer, 0, SCSI_SENSE_BUFFERSIZE);
2017 //printk("scsi%d.%c: sense buffer: ", info->host->host_no, '0' + SCpnt->device->id);
2018 //{ int i; for (i = 0; i < 32; i++) printk("%02x ", SCpnt->sense_buffer[i]); printk("\n"); }
2019 	/*
2020 	 * Note that we don't set SCpnt->result, since that should
2021 	 * reflect the status of the command that we were asked by
2022 	 * the upper layers to process.  This would have been set
2023 	 * correctly by fas216_std_done.
2024 	 */
2025 	scsi_eh_restore_cmnd(SCpnt, &info->ses);
2026 	fas216_cmd_priv(SCpnt)->scsi_done(SCpnt);
2027 }
2028 
2029 /**
2030  * fas216_std_done - finish processing of standard command
2031  * @info: interface that completed
2032  * @SCpnt: command that completed
2033  * @result: driver byte of result
2034  *
2035  * Finish processing of standard command
2036  */
2037 static void
2038 fas216_std_done(FAS216_Info *info, struct scsi_cmnd *SCpnt, unsigned int result)
2039 {
2040 	struct scsi_pointer *scsi_pointer = arm_scsi_pointer(SCpnt);
2041 
2042 	info->stats.fins += 1;
2043 
2044 	set_host_byte(SCpnt, result);
2045 	if (result == DID_OK)
2046 		scsi_msg_to_host_byte(SCpnt, info->scsi.SCp.Message);
2047 	set_status_byte(SCpnt, info->scsi.SCp.Status);
2048 
2049 	fas216_log_command(info, LOG_CONNECT, SCpnt,
2050 		"command complete, result=0x%08x", SCpnt->result);
2051 
2052 	/*
2053 	 * If the driver detected an error, we're all done.
2054 	 */
2055 	if (get_host_byte(SCpnt) != DID_OK)
2056 		goto done;
2057 
2058 	/*
2059 	 * If the command returned CHECK_CONDITION or COMMAND_TERMINATED
2060 	 * status, request the sense information.
2061 	 */
2062 	if (get_status_byte(SCpnt) == SAM_STAT_CHECK_CONDITION ||
2063 	    get_status_byte(SCpnt) == SAM_STAT_COMMAND_TERMINATED)
2064 		goto request_sense;
2065 
2066 	/*
2067 	 * If the command did not complete with GOOD status,
2068 	 * we are all done here.
2069 	 */
2070 	if (get_status_byte(SCpnt) != SAM_STAT_GOOD)
2071 		goto done;
2072 
2073 	/*
2074 	 * We have successfully completed a command.  Make sure that
2075 	 * we do not have any buffers left to transfer.  The world
2076 	 * is not perfect, and we seem to occasionally hit this.
2077 	 * It can be indicative of a buggy driver, target or the upper
2078 	 * levels of the SCSI code.
2079 	 */
2080 	if (info->scsi.SCp.ptr) {
2081 		switch (SCpnt->cmnd[0]) {
2082 		case INQUIRY:
2083 		case START_STOP:
2084 		case MODE_SENSE:
2085 			break;
2086 
2087 		default:
2088 			scmd_printk(KERN_ERR, SCpnt,
2089 				    "incomplete data transfer detected: res=%08X ptr=%p len=%X\n",
2090 				    SCpnt->result, info->scsi.SCp.ptr,
2091 				    info->scsi.SCp.this_residual);
2092 			scsi_print_command(SCpnt);
2093 			set_host_byte(SCpnt, DID_ERROR);
2094 			goto request_sense;
2095 		}
2096 	}
2097 
2098 done:
2099 	if (fas216_cmd_priv(SCpnt)->scsi_done) {
2100 		fas216_cmd_priv(SCpnt)->scsi_done(SCpnt);
2101 		return;
2102 	}
2103 
2104 	panic("scsi%d.H: null scsi_done function in fas216_done",
2105 		info->host->host_no);
2106 
2107 
2108 request_sense:
2109 	if (SCpnt->cmnd[0] == REQUEST_SENSE)
2110 		goto done;
2111 
2112 	scsi_eh_prep_cmnd(SCpnt, &info->ses, NULL, 0, ~0);
2113 	fas216_log_target(info, LOG_CONNECT, SCpnt->device->id,
2114 			  "requesting sense");
2115 	init_SCp(SCpnt);
2116 	scsi_pointer->Message = 0;
2117 	scsi_pointer->Status = 0;
2118 	SCpnt->host_scribble = (void *)fas216_rq_sns_done;
2119 
2120 	/*
2121 	 * Place this command into the high priority "request
2122 	 * sense" slot.  This will be the very next command
2123 	 * executed, unless a target connects to us.
2124 	 */
2125 	if (info->reqSCpnt)
2126 		printk(KERN_WARNING "scsi%d.%c: losing request command\n",
2127 			info->host->host_no, '0' + SCpnt->device->id);
2128 	info->reqSCpnt = SCpnt;
2129 }
2130 
2131 /**
2132  * fas216_done - complete processing for current command
2133  * @info: interface that completed
2134  * @result: driver byte of result
2135  *
2136  * Complete processing for current command
2137  */
2138 static void fas216_done(FAS216_Info *info, unsigned int result)
2139 {
2140 	void (*fn)(FAS216_Info *, struct scsi_cmnd *, unsigned int);
2141 	struct scsi_cmnd *SCpnt;
2142 	unsigned long flags;
2143 
2144 	fas216_checkmagic(info);
2145 
2146 	if (!info->SCpnt)
2147 		goto no_command;
2148 
2149 	SCpnt = info->SCpnt;
2150 	info->SCpnt = NULL;
2151     	info->scsi.phase = PHASE_IDLE;
2152 
2153 	if (info->scsi.aborting) {
2154 		fas216_log(info, 0, "uncaught abort - returning DID_ABORT");
2155 		result = DID_ABORT;
2156 		info->scsi.aborting = 0;
2157 	}
2158 
2159 	/*
2160 	 * Sanity check the completion - if we have zero bytes left
2161 	 * to transfer, we should not have a valid pointer.
2162 	 */
2163 	if (info->scsi.SCp.ptr && info->scsi.SCp.this_residual == 0) {
2164 		scmd_printk(KERN_INFO, SCpnt,
2165 			    "zero bytes left to transfer, but buffer pointer still valid: ptr=%p len=%08x\n",
2166 			    info->scsi.SCp.ptr, info->scsi.SCp.this_residual);
2167 		info->scsi.SCp.ptr = NULL;
2168 		scsi_print_command(SCpnt);
2169 	}
2170 
2171 	/*
2172 	 * Clear down this command as completed.  If we need to request
2173 	 * the sense information, fas216_kick will re-assert the busy
2174 	 * status.
2175 	 */
2176 	info->device[SCpnt->device->id].parity_check = 0;
2177 	clear_bit(SCpnt->device->id * 8 +
2178 		  (u8)(SCpnt->device->lun & 0x7), info->busyluns);
2179 
2180 	fn = (void (*)(FAS216_Info *, struct scsi_cmnd *, unsigned int))SCpnt->host_scribble;
2181 	fn(info, SCpnt, result);
2182 
2183 	if (info->scsi.irq) {
2184 		spin_lock_irqsave(&info->host_lock, flags);
2185 		if (info->scsi.phase == PHASE_IDLE)
2186 			fas216_kick(info);
2187 		spin_unlock_irqrestore(&info->host_lock, flags);
2188 	}
2189 	return;
2190 
2191 no_command:
2192 	panic("scsi%d.H: null command in fas216_done",
2193 		info->host->host_no);
2194 }
2195 
2196 /**
2197  * fas216_queue_command_internal - queue a command for the adapter to process
2198  * @SCpnt: Command to queue
2199  * @done: done function to call once command is complete
2200  *
2201  * Queue a command for adapter to process.
2202  * Returns: 0 on success, else error.
2203  * Notes: io_request_lock is held, interrupts are disabled.
2204  */
2205 static int fas216_queue_command_internal(struct scsi_cmnd *SCpnt,
2206 					 void (*done)(struct scsi_cmnd *))
2207 {
2208 	FAS216_Info *info = (FAS216_Info *)SCpnt->device->host->hostdata;
2209 	int result;
2210 
2211 	fas216_checkmagic(info);
2212 
2213 	fas216_log_command(info, LOG_CONNECT, SCpnt,
2214 			   "received command (%p)", SCpnt);
2215 
2216 	fas216_cmd_priv(SCpnt)->scsi_done = done;
2217 	SCpnt->host_scribble = (void *)fas216_std_done;
2218 	SCpnt->result = 0;
2219 
2220 	init_SCp(SCpnt);
2221 
2222 	info->stats.queues += 1;
2223 
2224 	spin_lock(&info->host_lock);
2225 
2226 	/*
2227 	 * Add command into execute queue and let it complete under
2228 	 * whatever scheme we're using.
2229 	 */
2230 	result = !queue_add_cmd_ordered(&info->queues.issue, SCpnt);
2231 
2232 	/*
2233 	 * If we successfully added the command,
2234 	 * kick the interface to get it moving.
2235 	 */
2236 	if (result == 0 && info->scsi.phase == PHASE_IDLE)
2237 		fas216_kick(info);
2238 	spin_unlock(&info->host_lock);
2239 
2240 	fas216_log_target(info, LOG_CONNECT, -1, "queue %s",
2241 		result ? "failure" : "success");
2242 
2243 	return result;
2244 }
2245 
2246 static int fas216_queue_command_lck(struct scsi_cmnd *SCpnt)
2247 {
2248 	return fas216_queue_command_internal(SCpnt, scsi_done);
2249 }
2250 
2251 DEF_SCSI_QCMD(fas216_queue_command)
2252 
2253 /**
2254  * fas216_internal_done - trigger restart of a waiting thread in fas216_noqueue_command
2255  * @SCpnt: Command to wake
2256  *
2257  * Trigger restart of a waiting thread in fas216_command
2258  */
2259 static void fas216_internal_done(struct scsi_cmnd *SCpnt)
2260 {
2261 	FAS216_Info *info = (FAS216_Info *)SCpnt->device->host->hostdata;
2262 
2263 	fas216_checkmagic(info);
2264 
2265 	info->internal_done = 1;
2266 }
2267 
2268 /**
2269  * fas216_noqueue_command - process a command for the adapter.
2270  * @SCpnt: Command to queue
2271  *
2272  * Queue a command for adapter to process.
2273  * Returns: scsi result code.
2274  * Notes: io_request_lock is held, interrupts are disabled.
2275  */
2276 static int fas216_noqueue_command_lck(struct scsi_cmnd *SCpnt)
2277 {
2278 	FAS216_Info *info = (FAS216_Info *)SCpnt->device->host->hostdata;
2279 
2280 	fas216_checkmagic(info);
2281 
2282 	/*
2283 	 * We should only be using this if we don't have an interrupt.
2284 	 * Provide some "incentive" to use the queueing code.
2285 	 */
2286 	BUG_ON(info->scsi.irq);
2287 
2288 	info->internal_done = 0;
2289 	fas216_queue_command_internal(SCpnt, fas216_internal_done);
2290 
2291 	/*
2292 	 * This wastes time, since we can't return until the command is
2293 	 * complete. We can't sleep either since we may get re-entered!
2294 	 * However, we must re-enable interrupts, or else we'll be
2295 	 * waiting forever.
2296 	 */
2297 	spin_unlock_irq(info->host->host_lock);
2298 
2299 	while (!info->internal_done) {
2300 		/*
2301 		 * If we don't have an IRQ, then we must poll the card for
2302 		 * it's interrupt, and use that to call this driver's
2303 		 * interrupt routine.  That way, we keep the command
2304 		 * progressing.  Maybe we can add some intelligence here
2305 		 * and go to sleep if we know that the device is going
2306 		 * to be some time (eg, disconnected).
2307 		 */
2308 		if (fas216_readb(info, REG_STAT) & STAT_INT) {
2309 			spin_lock_irq(info->host->host_lock);
2310 			fas216_intr(info);
2311 			spin_unlock_irq(info->host->host_lock);
2312 		}
2313 	}
2314 
2315 	spin_lock_irq(info->host->host_lock);
2316 
2317 	scsi_done(SCpnt);
2318 
2319 	return 0;
2320 }
2321 
2322 DEF_SCSI_QCMD(fas216_noqueue_command)
2323 
2324 /*
2325  * Error handler timeout function.  Indicate that we timed out,
2326  * and wake up any error handler process so it can continue.
2327  */
2328 static void fas216_eh_timer(struct timer_list *t)
2329 {
2330 	FAS216_Info *info = from_timer(info, t, eh_timer);
2331 
2332 	fas216_log(info, LOG_ERROR, "error handling timed out\n");
2333 
2334 	del_timer(&info->eh_timer);
2335 
2336 	if (info->rst_bus_status == 0)
2337 		info->rst_bus_status = -1;
2338 	if (info->rst_dev_status == 0)
2339 		info->rst_dev_status = -1;
2340 
2341 	wake_up(&info->eh_wait);
2342 }
2343 
2344 enum res_find {
2345 	res_failed,		/* not found			*/
2346 	res_success,		/* command on issue queue	*/
2347 	res_hw_abort		/* command on disconnected dev	*/
2348 };
2349 
2350 /**
2351  * fas216_do_abort - decide how to abort a command
2352  * @SCpnt: command to abort
2353  *
2354  * Decide how to abort a command.
2355  * Returns: abort status
2356  */
2357 static enum res_find fas216_find_command(FAS216_Info *info,
2358 					 struct scsi_cmnd *SCpnt)
2359 {
2360 	enum res_find res = res_failed;
2361 
2362 	if (queue_remove_cmd(&info->queues.issue, SCpnt)) {
2363 		/*
2364 		 * The command was on the issue queue, and has not been
2365 		 * issued yet.  We can remove the command from the queue,
2366 		 * and acknowledge the abort.  Neither the device nor the
2367 		 * interface know about the command.
2368 		 */
2369 		printk("on issue queue ");
2370 
2371 		res = res_success;
2372 	} else if (queue_remove_cmd(&info->queues.disconnected, SCpnt)) {
2373 		/*
2374 		 * The command was on the disconnected queue.  We must
2375 		 * reconnect with the device if possible, and send it
2376 		 * an abort message.
2377 		 */
2378 		printk("on disconnected queue ");
2379 
2380 		res = res_hw_abort;
2381 	} else if (info->SCpnt == SCpnt) {
2382 		printk("executing ");
2383 
2384 		switch (info->scsi.phase) {
2385 		/*
2386 		 * If the interface is idle, and the command is 'disconnectable',
2387 		 * then it is the same as on the disconnected queue.
2388 		 */
2389 		case PHASE_IDLE:
2390 			if (info->scsi.disconnectable) {
2391 				info->scsi.disconnectable = 0;
2392 				info->SCpnt = NULL;
2393 				res = res_hw_abort;
2394 			}
2395 			break;
2396 
2397 		default:
2398 			break;
2399 		}
2400 	} else if (info->origSCpnt == SCpnt) {
2401 		/*
2402 		 * The command will be executed next, but a command
2403 		 * is currently using the interface.  This is similar to
2404 		 * being on the issue queue, except the busylun bit has
2405 		 * been set.
2406 		 */
2407 		info->origSCpnt = NULL;
2408 		clear_bit(SCpnt->device->id * 8 +
2409 			  (u8)(SCpnt->device->lun & 0x7), info->busyluns);
2410 		printk("waiting for execution ");
2411 		res = res_success;
2412 	} else
2413 		printk("unknown ");
2414 
2415 	return res;
2416 }
2417 
2418 /**
2419  * fas216_eh_abort - abort this command
2420  * @SCpnt: command to abort
2421  *
2422  * Abort this command.
2423  * Returns: FAILED if unable to abort
2424  * Notes: io_request_lock is taken, and irqs are disabled
2425  */
2426 int fas216_eh_abort(struct scsi_cmnd *SCpnt)
2427 {
2428 	FAS216_Info *info = (FAS216_Info *)SCpnt->device->host->hostdata;
2429 	int result = FAILED;
2430 
2431 	fas216_checkmagic(info);
2432 
2433 	info->stats.aborts += 1;
2434 
2435 	scmd_printk(KERN_WARNING, SCpnt, "abort command\n");
2436 
2437 	print_debug_list();
2438 	fas216_dumpstate(info);
2439 
2440 	switch (fas216_find_command(info, SCpnt)) {
2441 	/*
2442 	 * We found the command, and cleared it out.  Either
2443 	 * the command is still known to be executing on the
2444 	 * target, or the busylun bit is not set.
2445 	 */
2446 	case res_success:
2447 		scmd_printk(KERN_WARNING, SCpnt, "abort %p success\n", SCpnt);
2448 		result = SUCCESS;
2449 		break;
2450 
2451 	/*
2452 	 * We need to reconnect to the target and send it an
2453 	 * ABORT or ABORT_TAG message.  We can only do this
2454 	 * if the bus is free.
2455 	 */
2456 	case res_hw_abort:
2457 
2458 	/*
2459 	 * We are unable to abort the command for some reason.
2460 	 */
2461 	default:
2462 	case res_failed:
2463 		scmd_printk(KERN_WARNING, SCpnt, "abort %p failed\n", SCpnt);
2464 		break;
2465 	}
2466 
2467 	return result;
2468 }
2469 
2470 /**
2471  * fas216_eh_device_reset - Reset the device associated with this command
2472  * @SCpnt: command specifing device to reset
2473  *
2474  * Reset the device associated with this command.
2475  * Returns: FAILED if unable to reset.
2476  * Notes: We won't be re-entered, so we'll only have one device
2477  * reset on the go at one time.
2478  */
2479 int fas216_eh_device_reset(struct scsi_cmnd *SCpnt)
2480 {
2481 	FAS216_Info *info = (FAS216_Info *)SCpnt->device->host->hostdata;
2482 	unsigned long flags;
2483 	int i, res = FAILED, target = SCpnt->device->id;
2484 
2485 	fas216_log(info, LOG_ERROR, "device reset for target %d", target);
2486 
2487 	spin_lock_irqsave(&info->host_lock, flags);
2488 
2489 	do {
2490 		/*
2491 		 * If we are currently connected to a device, and
2492 		 * it is the device we want to reset, there is
2493 		 * nothing we can do here.  Chances are it is stuck,
2494 		 * and we need a bus reset.
2495 		 */
2496 		if (info->SCpnt && !info->scsi.disconnectable &&
2497 		    info->SCpnt->device->id == SCpnt->device->id)
2498 			break;
2499 
2500 		/*
2501 		 * We're going to be resetting this device.  Remove
2502 		 * all pending commands from the driver.  By doing
2503 		 * so, we guarantee that we won't touch the command
2504 		 * structures except to process the reset request.
2505 		 */
2506 		queue_remove_all_target(&info->queues.issue, target);
2507 		queue_remove_all_target(&info->queues.disconnected, target);
2508 		if (info->origSCpnt && info->origSCpnt->device->id == target)
2509 			info->origSCpnt = NULL;
2510 		if (info->reqSCpnt && info->reqSCpnt->device->id == target)
2511 			info->reqSCpnt = NULL;
2512 		for (i = 0; i < 8; i++)
2513 			clear_bit(target * 8 + i, info->busyluns);
2514 
2515 		/*
2516 		 * Hijack this SCSI command structure to send
2517 		 * a bus device reset message to this device.
2518 		 */
2519 		SCpnt->host_scribble = (void *)fas216_devicereset_done;
2520 
2521 		info->rst_dev_status = 0;
2522 		info->rstSCpnt = SCpnt;
2523 
2524 		if (info->scsi.phase == PHASE_IDLE)
2525 			fas216_kick(info);
2526 
2527 		mod_timer(&info->eh_timer, jiffies + 30 * HZ);
2528 		spin_unlock_irqrestore(&info->host_lock, flags);
2529 
2530 		/*
2531 		 * Wait up to 30 seconds for the reset to complete.
2532 		 */
2533 		wait_event(info->eh_wait, info->rst_dev_status);
2534 
2535 		del_timer_sync(&info->eh_timer);
2536 		spin_lock_irqsave(&info->host_lock, flags);
2537 		info->rstSCpnt = NULL;
2538 
2539 		if (info->rst_dev_status == 1)
2540 			res = SUCCESS;
2541 	} while (0);
2542 
2543 	SCpnt->host_scribble = NULL;
2544 	spin_unlock_irqrestore(&info->host_lock, flags);
2545 
2546 	fas216_log(info, LOG_ERROR, "device reset complete: %s\n",
2547 		   res == SUCCESS ? "success" : "failed");
2548 
2549 	return res;
2550 }
2551 
2552 /**
2553  * fas216_eh_bus_reset - Reset the bus associated with the command
2554  * @SCpnt: command specifing bus to reset
2555  *
2556  * Reset the bus associated with the command.
2557  * Returns: FAILED if unable to reset.
2558  * Notes: Further commands are blocked.
2559  */
2560 int fas216_eh_bus_reset(struct scsi_cmnd *SCpnt)
2561 {
2562 	FAS216_Info *info = (FAS216_Info *)SCpnt->device->host->hostdata;
2563 	unsigned long flags;
2564 	struct scsi_device *SDpnt;
2565 
2566 	fas216_checkmagic(info);
2567 	fas216_log(info, LOG_ERROR, "resetting bus");
2568 
2569 	info->stats.bus_resets += 1;
2570 
2571 	spin_lock_irqsave(&info->host_lock, flags);
2572 
2573 	/*
2574 	 * Stop all activity on this interface.
2575 	 */
2576 	fas216_aborttransfer(info);
2577 	fas216_writeb(info, REG_CNTL3, info->scsi.cfg[2]);
2578 
2579 	/*
2580 	 * Clear any pending interrupts.
2581 	 */
2582 	while (fas216_readb(info, REG_STAT) & STAT_INT)
2583 		fas216_readb(info, REG_INST);
2584 
2585 	info->rst_bus_status = 0;
2586 
2587 	/*
2588 	 * For each attached hard-reset device, clear out
2589 	 * all command structures.  Leave the running
2590 	 * command in place.
2591 	 */
2592 	shost_for_each_device(SDpnt, info->host) {
2593 		int i;
2594 
2595 		if (SDpnt->soft_reset)
2596 			continue;
2597 
2598 		queue_remove_all_target(&info->queues.issue, SDpnt->id);
2599 		queue_remove_all_target(&info->queues.disconnected, SDpnt->id);
2600 		if (info->origSCpnt && info->origSCpnt->device->id == SDpnt->id)
2601 			info->origSCpnt = NULL;
2602 		if (info->reqSCpnt && info->reqSCpnt->device->id == SDpnt->id)
2603 			info->reqSCpnt = NULL;
2604 		info->SCpnt = NULL;
2605 
2606 		for (i = 0; i < 8; i++)
2607 			clear_bit(SDpnt->id * 8 + i, info->busyluns);
2608 	}
2609 
2610 	info->scsi.phase = PHASE_IDLE;
2611 
2612 	/*
2613 	 * Reset the SCSI bus.  Device cleanup happens in
2614 	 * the interrupt handler.
2615 	 */
2616 	fas216_cmd(info, CMD_RESETSCSI);
2617 
2618 	mod_timer(&info->eh_timer, jiffies + HZ);
2619 	spin_unlock_irqrestore(&info->host_lock, flags);
2620 
2621 	/*
2622 	 * Wait one second for the interrupt.
2623 	 */
2624 	wait_event(info->eh_wait, info->rst_bus_status);
2625 	del_timer_sync(&info->eh_timer);
2626 
2627 	fas216_log(info, LOG_ERROR, "bus reset complete: %s\n",
2628 		   info->rst_bus_status == 1 ? "success" : "failed");
2629 
2630 	return info->rst_bus_status == 1 ? SUCCESS : FAILED;
2631 }
2632 
2633 /**
2634  * fas216_init_chip - Initialise FAS216 state after reset
2635  * @info: state structure for interface
2636  *
2637  * Initialise FAS216 state after reset
2638  */
2639 static void fas216_init_chip(FAS216_Info *info)
2640 {
2641 	unsigned int clock = ((info->ifcfg.clockrate - 1) / 5 + 1) & 7;
2642 	fas216_writeb(info, REG_CLKF, clock);
2643 	fas216_writeb(info, REG_CNTL1, info->scsi.cfg[0]);
2644 	fas216_writeb(info, REG_CNTL2, info->scsi.cfg[1]);
2645 	fas216_writeb(info, REG_CNTL3, info->scsi.cfg[2]);
2646 	fas216_writeb(info, REG_STIM, info->ifcfg.select_timeout);
2647 	fas216_writeb(info, REG_SOF, 0);
2648 	fas216_writeb(info, REG_STP, info->scsi.async_stp);
2649 	fas216_writeb(info, REG_CNTL1, info->scsi.cfg[0]);
2650 }
2651 
2652 /**
2653  * fas216_eh_host_reset - Reset the host associated with this command
2654  * @SCpnt: command specifing host to reset
2655  *
2656  * Reset the host associated with this command.
2657  * Returns: FAILED if unable to reset.
2658  * Notes: io_request_lock is taken, and irqs are disabled
2659  */
2660 int fas216_eh_host_reset(struct scsi_cmnd *SCpnt)
2661 {
2662 	FAS216_Info *info = (FAS216_Info *)SCpnt->device->host->hostdata;
2663 
2664 	spin_lock_irq(info->host->host_lock);
2665 
2666 	fas216_checkmagic(info);
2667 
2668 	fas216_log(info, LOG_ERROR, "resetting host");
2669 
2670 	/*
2671 	 * Reset the SCSI chip.
2672 	 */
2673 	fas216_cmd(info, CMD_RESETCHIP);
2674 
2675 	/*
2676 	 * Ugly ugly ugly!
2677 	 * We need to release the host_lock and enable
2678 	 * IRQs if we sleep, but we must relock and disable
2679 	 * IRQs after the sleep.
2680 	 */
2681 	spin_unlock_irq(info->host->host_lock);
2682 	msleep(50 * 1000/100);
2683 	spin_lock_irq(info->host->host_lock);
2684 
2685 	/*
2686 	 * Release the SCSI reset.
2687 	 */
2688 	fas216_cmd(info, CMD_NOP);
2689 
2690 	fas216_init_chip(info);
2691 
2692 	spin_unlock_irq(info->host->host_lock);
2693 	return SUCCESS;
2694 }
2695 
2696 #define TYPE_UNKNOWN	0
2697 #define TYPE_NCR53C90	1
2698 #define TYPE_NCR53C90A	2
2699 #define TYPE_NCR53C9x	3
2700 #define TYPE_Am53CF94	4
2701 #define TYPE_EmFAS216	5
2702 #define TYPE_QLFAS216	6
2703 
2704 static char *chip_types[] = {
2705 	"unknown",
2706 	"NS NCR53C90",
2707 	"NS NCR53C90A",
2708 	"NS NCR53C9x",
2709 	"AMD Am53CF94",
2710 	"Emulex FAS216",
2711 	"QLogic FAS216"
2712 };
2713 
2714 static int fas216_detect_type(FAS216_Info *info)
2715 {
2716 	int family, rev;
2717 
2718 	/*
2719 	 * Reset the chip.
2720 	 */
2721 	fas216_writeb(info, REG_CMD, CMD_RESETCHIP);
2722 	udelay(50);
2723 	fas216_writeb(info, REG_CMD, CMD_NOP);
2724 
2725 	/*
2726 	 * Check to see if control reg 2 is present.
2727 	 */
2728 	fas216_writeb(info, REG_CNTL3, 0);
2729 	fas216_writeb(info, REG_CNTL2, CNTL2_S2FE);
2730 
2731 	/*
2732 	 * If we are unable to read back control reg 2
2733 	 * correctly, it is not present, and we have a
2734 	 * NCR53C90.
2735 	 */
2736 	if ((fas216_readb(info, REG_CNTL2) & (~0xe0)) != CNTL2_S2FE)
2737 		return TYPE_NCR53C90;
2738 
2739 	/*
2740 	 * Now, check control register 3
2741 	 */
2742 	fas216_writeb(info, REG_CNTL2, 0);
2743 	fas216_writeb(info, REG_CNTL3, 0);
2744 	fas216_writeb(info, REG_CNTL3, 5);
2745 
2746 	/*
2747 	 * If we are unable to read the register back
2748 	 * correctly, we have a NCR53C90A
2749 	 */
2750 	if (fas216_readb(info, REG_CNTL3) != 5)
2751 		return TYPE_NCR53C90A;
2752 
2753 	/*
2754 	 * Now read the ID from the chip.
2755 	 */
2756 	fas216_writeb(info, REG_CNTL3, 0);
2757 
2758 	fas216_writeb(info, REG_CNTL3, CNTL3_ADIDCHK);
2759 	fas216_writeb(info, REG_CNTL3, 0);
2760 
2761 	fas216_writeb(info, REG_CMD, CMD_RESETCHIP);
2762 	udelay(50);
2763 	fas216_writeb(info, REG_CMD, CMD_WITHDMA | CMD_NOP);
2764 
2765 	fas216_writeb(info, REG_CNTL2, CNTL2_ENF);
2766 	fas216_writeb(info, REG_CMD, CMD_RESETCHIP);
2767 	udelay(50);
2768 	fas216_writeb(info, REG_CMD, CMD_NOP);
2769 
2770 	rev     = fas216_readb(info, REG_ID);
2771 	family  = rev >> 3;
2772 	rev    &= 7;
2773 
2774 	switch (family) {
2775 	case 0x01:
2776 		if (rev == 4)
2777 			return TYPE_Am53CF94;
2778 		break;
2779 
2780 	case 0x02:
2781 		switch (rev) {
2782 		case 2:
2783 			return TYPE_EmFAS216;
2784 		case 3:
2785 			return TYPE_QLFAS216;
2786 		}
2787 		break;
2788 
2789 	default:
2790 		break;
2791 	}
2792 	printk("family %x rev %x\n", family, rev);
2793 	return TYPE_NCR53C9x;
2794 }
2795 
2796 /**
2797  * fas216_reset_state - Initialise driver internal state
2798  * @info: state to initialise
2799  *
2800  * Initialise driver internal state
2801  */
2802 static void fas216_reset_state(FAS216_Info *info)
2803 {
2804 	int i;
2805 
2806 	fas216_checkmagic(info);
2807 
2808 	fas216_bus_reset(info);
2809 
2810 	/*
2811 	 * Clear out all stale info in our state structure
2812 	 */
2813 	memset(info->busyluns, 0, sizeof(info->busyluns));
2814 	info->scsi.disconnectable = 0;
2815 	info->scsi.aborting = 0;
2816 
2817 	for (i = 0; i < 8; i++) {
2818 		info->device[i].parity_enabled	= 0;
2819 		info->device[i].parity_check	= 1;
2820 	}
2821 
2822 	/*
2823 	 * Drain all commands on disconnected queue
2824 	 */
2825 	while (queue_remove(&info->queues.disconnected) != NULL);
2826 
2827 	/*
2828 	 * Remove executing commands.
2829 	 */
2830 	info->SCpnt     = NULL;
2831 	info->reqSCpnt  = NULL;
2832 	info->rstSCpnt  = NULL;
2833 	info->origSCpnt = NULL;
2834 }
2835 
2836 /**
2837  * fas216_init - initialise FAS/NCR/AMD SCSI structures.
2838  * @host: a driver-specific filled-out structure
2839  *
2840  * Initialise FAS/NCR/AMD SCSI structures.
2841  * Returns: 0 on success
2842  */
2843 int fas216_init(struct Scsi_Host *host)
2844 {
2845 	FAS216_Info *info = (FAS216_Info *)host->hostdata;
2846 
2847 	info->magic_start    = MAGIC;
2848 	info->magic_end      = MAGIC;
2849 	info->host           = host;
2850 	info->scsi.cfg[0]    = host->this_id | CNTL1_PERE;
2851 	info->scsi.cfg[1]    = CNTL2_ENF | CNTL2_S2FE;
2852 	info->scsi.cfg[2]    = info->ifcfg.cntl3 |
2853 			       CNTL3_ADIDCHK | CNTL3_QTAG | CNTL3_G2CB | CNTL3_LBTM;
2854 	info->scsi.async_stp = fas216_syncperiod(info, info->ifcfg.asyncperiod);
2855 
2856 	info->rst_dev_status = -1;
2857 	info->rst_bus_status = -1;
2858 	init_waitqueue_head(&info->eh_wait);
2859 	timer_setup(&info->eh_timer, fas216_eh_timer, 0);
2860 
2861 	spin_lock_init(&info->host_lock);
2862 
2863 	memset(&info->stats, 0, sizeof(info->stats));
2864 
2865 	msgqueue_initialise(&info->scsi.msgs);
2866 
2867 	if (!queue_initialise(&info->queues.issue))
2868 		return -ENOMEM;
2869 
2870 	if (!queue_initialise(&info->queues.disconnected)) {
2871 		queue_free(&info->queues.issue);
2872 		return -ENOMEM;
2873 	}
2874 
2875 	return 0;
2876 }
2877 
2878 /**
2879  * fas216_add - initialise FAS/NCR/AMD SCSI ic.
2880  * @host: a driver-specific filled-out structure
2881  * @dev: parent device
2882  *
2883  * Initialise FAS/NCR/AMD SCSI ic.
2884  * Returns: 0 on success
2885  */
2886 int fas216_add(struct Scsi_Host *host, struct device *dev)
2887 {
2888 	FAS216_Info *info = (FAS216_Info *)host->hostdata;
2889 	int type, ret;
2890 
2891 	if (info->ifcfg.clockrate <= 10 || info->ifcfg.clockrate > 40) {
2892 		printk(KERN_CRIT "fas216: invalid clock rate %u MHz\n",
2893 			info->ifcfg.clockrate);
2894 		return -EINVAL;
2895 	}
2896 
2897 	fas216_reset_state(info);
2898 	type = fas216_detect_type(info);
2899 	info->scsi.type = chip_types[type];
2900 
2901 	udelay(300);
2902 
2903 	/*
2904 	 * Initialise the chip correctly.
2905 	 */
2906 	fas216_init_chip(info);
2907 
2908 	/*
2909 	 * Reset the SCSI bus.  We don't want to see
2910 	 * the resulting reset interrupt, so mask it
2911 	 * out.
2912 	 */
2913 	fas216_writeb(info, REG_CNTL1, info->scsi.cfg[0] | CNTL1_DISR);
2914 	fas216_writeb(info, REG_CMD, CMD_RESETSCSI);
2915 
2916 	/*
2917 	 * scsi standard says wait 250ms
2918 	 */
2919 	spin_unlock_irq(info->host->host_lock);
2920 	msleep(100*1000/100);
2921 	spin_lock_irq(info->host->host_lock);
2922 
2923 	fas216_writeb(info, REG_CNTL1, info->scsi.cfg[0]);
2924 	fas216_readb(info, REG_INST);
2925 
2926 	fas216_checkmagic(info);
2927 
2928 	ret = scsi_add_host(host, dev);
2929 	if (ret)
2930 		fas216_writeb(info, REG_CMD, CMD_RESETCHIP);
2931 	else
2932 		scsi_scan_host(host);
2933 
2934 	return ret;
2935 }
2936 
2937 void fas216_remove(struct Scsi_Host *host)
2938 {
2939 	FAS216_Info *info = (FAS216_Info *)host->hostdata;
2940 
2941 	fas216_checkmagic(info);
2942 	scsi_remove_host(host);
2943 
2944 	fas216_writeb(info, REG_CMD, CMD_RESETCHIP);
2945 	scsi_host_put(host);
2946 }
2947 
2948 /**
2949  * fas216_release - release all resources for FAS/NCR/AMD SCSI ic.
2950  * @host: a driver-specific filled-out structure
2951  *
2952  * release all resources and put everything to bed for FAS/NCR/AMD SCSI ic.
2953  */
2954 void fas216_release(struct Scsi_Host *host)
2955 {
2956 	FAS216_Info *info = (FAS216_Info *)host->hostdata;
2957 
2958 	queue_free(&info->queues.disconnected);
2959 	queue_free(&info->queues.issue);
2960 }
2961 
2962 void fas216_print_host(FAS216_Info *info, struct seq_file *m)
2963 {
2964 	seq_printf(m,
2965 			"\n"
2966 			"Chip    : %s\n"
2967 			" Address: 0x%p\n"
2968 			" IRQ    : %d\n"
2969 			" DMA    : %d\n",
2970 			info->scsi.type, info->scsi.io_base,
2971 			info->scsi.irq, info->scsi.dma);
2972 }
2973 
2974 void fas216_print_stats(FAS216_Info *info, struct seq_file *m)
2975 {
2976 	seq_printf(m, "\n"
2977 			"Command Statistics:\n"
2978 			" Queued     : %u\n"
2979 			" Issued     : %u\n"
2980 			" Completed  : %u\n"
2981 			" Reads      : %u\n"
2982 			" Writes     : %u\n"
2983 			" Others     : %u\n"
2984 			" Disconnects: %u\n"
2985 			" Aborts     : %u\n"
2986 			" Bus resets : %u\n"
2987 			" Host resets: %u\n",
2988 			info->stats.queues,	 info->stats.removes,
2989 			info->stats.fins,	 info->stats.reads,
2990 			info->stats.writes,	 info->stats.miscs,
2991 			info->stats.disconnects, info->stats.aborts,
2992 			info->stats.bus_resets,	 info->stats.host_resets);
2993 }
2994 
2995 void fas216_print_devices(FAS216_Info *info, struct seq_file *m)
2996 {
2997 	struct fas216_device *dev;
2998 	struct scsi_device *scd;
2999 
3000 	seq_puts(m, "Device/Lun TaggedQ       Parity   Sync\n");
3001 
3002 	shost_for_each_device(scd, info->host) {
3003 		dev = &info->device[scd->id];
3004 		seq_printf(m, "     %d/%llu   ", scd->id, scd->lun);
3005 		if (scd->tagged_supported)
3006 			seq_printf(m, "%3sabled ",
3007 				     scd->simple_tags ? "en" : "dis");
3008 		else
3009 			seq_puts(m, "unsupported   ");
3010 
3011 		seq_printf(m, "%3sabled ", dev->parity_enabled ? "en" : "dis");
3012 
3013 		if (dev->sof)
3014 			seq_printf(m, "offset %d, %d ns\n",
3015 				     dev->sof, dev->period * 4);
3016 		else
3017 			seq_puts(m, "async\n");
3018 	}
3019 }
3020 
3021 EXPORT_SYMBOL(fas216_init);
3022 EXPORT_SYMBOL(fas216_add);
3023 EXPORT_SYMBOL(fas216_queue_command);
3024 EXPORT_SYMBOL(fas216_noqueue_command);
3025 EXPORT_SYMBOL(fas216_intr);
3026 EXPORT_SYMBOL(fas216_remove);
3027 EXPORT_SYMBOL(fas216_release);
3028 EXPORT_SYMBOL(fas216_eh_abort);
3029 EXPORT_SYMBOL(fas216_eh_device_reset);
3030 EXPORT_SYMBOL(fas216_eh_bus_reset);
3031 EXPORT_SYMBOL(fas216_eh_host_reset);
3032 EXPORT_SYMBOL(fas216_print_host);
3033 EXPORT_SYMBOL(fas216_print_stats);
3034 EXPORT_SYMBOL(fas216_print_devices);
3035 
3036 MODULE_AUTHOR("Russell King");
3037 MODULE_DESCRIPTION("Generic FAS216/NCR53C9x driver core");
3038 MODULE_LICENSE("GPL");
3039