xref: /openbmc/linux/drivers/scsi/NCR5380.c (revision 95e9fd10)
1 /*
2  * NCR 5380 generic driver routines.  These should make it *trivial*
3  *      to implement 5380 SCSI drivers under Linux with a non-trantor
4  *      architecture.
5  *
6  *      Note that these routines also work with NR53c400 family chips.
7  *
8  * Copyright 1993, Drew Eckhardt
9  *      Visionary Computing
10  *      (Unix and Linux consulting and custom programming)
11  *      drew@colorado.edu
12  *      +1 (303) 666-5836
13  *
14  * DISTRIBUTION RELEASE 6.
15  *
16  * For more information, please consult
17  *
18  * NCR 5380 Family
19  * SCSI Protocol Controller
20  * Databook
21  *
22  * NCR Microelectronics
23  * 1635 Aeroplaza Drive
24  * Colorado Springs, CO 80916
25  * 1+ (719) 578-3400
26  * 1+ (800) 334-5454
27  */
28 
29 /*
30  * $Log: NCR5380.c,v $
31 
32  * Revision 1.10 1998/9/2	Alan Cox
33  *				(alan@lxorguk.ukuu.org.uk)
34  * Fixed up the timer lockups reported so far. Things still suck. Looking
35  * forward to 2.3 and per device request queues. Then it'll be possible to
36  * SMP thread this beast and improve life no end.
37 
38  * Revision 1.9  1997/7/27	Ronald van Cuijlenborg
39  *				(ronald.van.cuijlenborg@tip.nl or nutty@dds.nl)
40  * (hopefully) fixed and enhanced USLEEP
41  * added support for DTC3181E card (for Mustek scanner)
42  *
43 
44  * Revision 1.8			Ingmar Baumgart
45  *				(ingmar@gonzo.schwaben.de)
46  * added support for NCR53C400a card
47  *
48 
49  * Revision 1.7  1996/3/2       Ray Van Tassle (rayvt@comm.mot.com)
50  * added proc_info
51  * added support needed for DTC 3180/3280
52  * fixed a couple of bugs
53  *
54 
55  * Revision 1.5  1994/01/19  09:14:57  drew
56  * Fixed udelay() hack that was being used on DATAOUT phases
57  * instead of a proper wait for the final handshake.
58  *
59  * Revision 1.4  1994/01/19  06:44:25  drew
60  * *** empty log message ***
61  *
62  * Revision 1.3  1994/01/19  05:24:40  drew
63  * Added support for TCR LAST_BYTE_SENT bit.
64  *
65  * Revision 1.2  1994/01/15  06:14:11  drew
66  * REAL DMA support, bug fixes.
67  *
68  * Revision 1.1  1994/01/15  06:00:54  drew
69  * Initial revision
70  *
71  */
72 
73 /*
74  * Further development / testing that should be done :
75  * 1.  Cleanup the NCR5380_transfer_dma function and DMA operation complete
76  *     code so that everything does the same thing that's done at the
77  *     end of a pseudo-DMA read operation.
78  *
79  * 2.  Fix REAL_DMA (interrupt driven, polled works fine) -
80  *     basically, transfer size needs to be reduced by one
81  *     and the last byte read as is done with PSEUDO_DMA.
82  *
83  * 4.  Test SCSI-II tagged queueing (I have no devices which support
84  *      tagged queueing)
85  *
86  * 5.  Test linked command handling code after Eric is ready with
87  *      the high level code.
88  */
89 #include <scsi/scsi_dbg.h>
90 #include <scsi/scsi_transport_spi.h>
91 
92 #ifndef NDEBUG
93 #define NDEBUG 0
94 #endif
95 #ifndef NDEBUG_ABORT
96 #define NDEBUG_ABORT 0
97 #endif
98 
99 #if (NDEBUG & NDEBUG_LISTS)
100 #define LIST(x,y) {printk("LINE:%d   Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); if ((x)==(y)) udelay(5); }
101 #define REMOVE(w,x,y,z) {printk("LINE:%d   Removing: %p->%p  %p->%p \n", __LINE__, (void*)(w), (void*)(x), (void*)(y), (void*)(z)); if ((x)==(y)) udelay(5); }
102 #else
103 #define LIST(x,y)
104 #define REMOVE(w,x,y,z)
105 #endif
106 
107 #ifndef notyet
108 #undef LINKED
109 #undef REAL_DMA
110 #endif
111 
112 #ifdef REAL_DMA_POLL
113 #undef READ_OVERRUNS
114 #define READ_OVERRUNS
115 #endif
116 
117 #ifdef BOARD_REQUIRES_NO_DELAY
118 #define io_recovery_delay(x)
119 #else
120 #define io_recovery_delay(x)	udelay(x)
121 #endif
122 
123 /*
124  * Design
125  *
126  * This is a generic 5380 driver.  To use it on a different platform,
127  * one simply writes appropriate system specific macros (ie, data
128  * transfer - some PC's will use the I/O bus, 68K's must use
129  * memory mapped) and drops this file in their 'C' wrapper.
130  *
131  * (Note from hch:  unfortunately it was not enough for the different
132  * m68k folks and instead of improving this driver they copied it
133  * and hacked it up for their needs.  As a consequence they lost
134  * most updates to this driver.  Maybe someone will fix all these
135  * drivers to use a common core one day..)
136  *
137  * As far as command queueing, two queues are maintained for
138  * each 5380 in the system - commands that haven't been issued yet,
139  * and commands that are currently executing.  This means that an
140  * unlimited number of commands may be queued, letting
141  * more commands propagate from the higher driver levels giving higher
142  * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported,
143  * allowing multiple commands to propagate all the way to a SCSI-II device
144  * while a command is already executing.
145  *
146  *
147  * Issues specific to the NCR5380 :
148  *
149  * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
150  * piece of hardware that requires you to sit in a loop polling for
151  * the REQ signal as long as you are connected.  Some devices are
152  * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
153  * while doing long seek operations.
154  *
155  * The workaround for this is to keep track of devices that have
156  * disconnected.  If the device hasn't disconnected, for commands that
157  * should disconnect, we do something like
158  *
159  * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
160  *
161  * Some tweaking of N and M needs to be done.  An algorithm based
162  * on "time to data" would give the best results as long as short time
163  * to datas (ie, on the same track) were considered, however these
164  * broken devices are the exception rather than the rule and I'd rather
165  * spend my time optimizing for the normal case.
166  *
167  * Architecture :
168  *
169  * At the heart of the design is a coroutine, NCR5380_main,
170  * which is started from a workqueue for each NCR5380 host in the
171  * system.  It attempts to establish I_T_L or I_T_L_Q nexuses by
172  * removing the commands from the issue queue and calling
173  * NCR5380_select() if a nexus is not established.
174  *
175  * Once a nexus is established, the NCR5380_information_transfer()
176  * phase goes through the various phases as instructed by the target.
177  * if the target goes into MSG IN and sends a DISCONNECT message,
178  * the command structure is placed into the per instance disconnected
179  * queue, and NCR5380_main tries to find more work.  If the target is
180  * idle for too long, the system will try to sleep.
181  *
182  * If a command has disconnected, eventually an interrupt will trigger,
183  * calling NCR5380_intr()  which will in turn call NCR5380_reselect
184  * to reestablish a nexus.  This will run main if necessary.
185  *
186  * On command termination, the done function will be called as
187  * appropriate.
188  *
189  * SCSI pointers are maintained in the SCp field of SCSI command
190  * structures, being initialized after the command is connected
191  * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
192  * Note that in violation of the standard, an implicit SAVE POINTERS operation
193  * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
194  */
195 
196 /*
197  * Using this file :
198  * This file a skeleton Linux SCSI driver for the NCR 5380 series
199  * of chips.  To use it, you write an architecture specific functions
200  * and macros and include this file in your driver.
201  *
202  * These macros control options :
203  * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be
204  *      defined.
205  *
206  * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
207  *      for commands that return with a CHECK CONDITION status.
208  *
209  * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
210  *      transceivers.
211  *
212  * DONT_USE_INTR - if defined, never use interrupts, even if we probe or
213  *      override-configure an IRQ.
214  *
215  * LIMIT_TRANSFERSIZE - if defined, limit the pseudo-dma transfers to 512
216  *      bytes at a time.  Since interrupts are disabled by default during
217  *      these transfers, we might need this to give reasonable interrupt
218  *      service time if the transfer size gets too large.
219  *
220  * LINKED - if defined, linked commands are supported.
221  *
222  * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
223  *
224  * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
225  *
226  * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't
227  *      rely on phase mismatch and EOP interrupts to determine end
228  *      of phase.
229  *
230  * UNSAFE - leave interrupts enabled during pseudo-DMA transfers.  You
231  *          only really want to use this if you're having a problem with
232  *          dropped characters during high speed communications, and even
233  *          then, you're going to be better off twiddling with transfersize
234  *          in the high level code.
235  *
236  * Defaults for these will be provided although the user may want to adjust
237  * these to allocate CPU resources to the SCSI driver or "real" code.
238  *
239  * USLEEP_SLEEP - amount of time, in jiffies, to sleep
240  *
241  * USLEEP_POLL - amount of time, in jiffies, to poll
242  *
243  * These macros MUST be defined :
244  * NCR5380_local_declare() - declare any local variables needed for your
245  *      transfer routines.
246  *
247  * NCR5380_setup(instance) - initialize any local variables needed from a given
248  *      instance of the host adapter for NCR5380_{read,write,pread,pwrite}
249  *
250  * NCR5380_read(register)  - read from the specified register
251  *
252  * NCR5380_write(register, value) - write to the specific register
253  *
254  * NCR5380_implementation_fields  - additional fields needed for this
255  *      specific implementation of the NCR5380
256  *
257  * Either real DMA *or* pseudo DMA may be implemented
258  * REAL functions :
259  * NCR5380_REAL_DMA should be defined if real DMA is to be used.
260  * Note that the DMA setup functions should return the number of bytes
261  *      that they were able to program the controller for.
262  *
263  * Also note that generic i386/PC versions of these macros are
264  *      available as NCR5380_i386_dma_write_setup,
265  *      NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
266  *
267  * NCR5380_dma_write_setup(instance, src, count) - initialize
268  * NCR5380_dma_read_setup(instance, dst, count) - initialize
269  * NCR5380_dma_residual(instance); - residual count
270  *
271  * PSEUDO functions :
272  * NCR5380_pwrite(instance, src, count)
273  * NCR5380_pread(instance, dst, count);
274  *
275  * The generic driver is initialized by calling NCR5380_init(instance),
276  * after setting the appropriate host specific fields and ID.  If the
277  * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
278  * possible) function may be used.
279  */
280 
281 static int do_abort(struct Scsi_Host *host);
282 static void do_reset(struct Scsi_Host *host);
283 
284 /*
285  *	initialize_SCp		-	init the scsi pointer field
286  *	@cmd: command block to set up
287  *
288  *	Set up the internal fields in the SCSI command.
289  */
290 
291 static __inline__ void initialize_SCp(Scsi_Cmnd * cmd)
292 {
293 	/*
294 	 * Initialize the Scsi Pointer field so that all of the commands in the
295 	 * various queues are valid.
296 	 */
297 
298 	if (scsi_bufflen(cmd)) {
299 		cmd->SCp.buffer = scsi_sglist(cmd);
300 		cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
301 		cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
302 		cmd->SCp.this_residual = cmd->SCp.buffer->length;
303 	} else {
304 		cmd->SCp.buffer = NULL;
305 		cmd->SCp.buffers_residual = 0;
306 		cmd->SCp.ptr = NULL;
307 		cmd->SCp.this_residual = 0;
308 	}
309 }
310 
311 /**
312  *	NCR5380_poll_politely	-	wait for NCR5380 status bits
313  *	@instance: controller to poll
314  *	@reg: 5380 register to poll
315  *	@bit: Bitmask to check
316  *	@val: Value required to exit
317  *
318  *	Polls the NCR5380 in a reasonably efficient manner waiting for
319  *	an event to occur, after a short quick poll we begin giving the
320  *	CPU back in non IRQ contexts
321  *
322  *	Returns the value of the register or a negative error code.
323  */
324 
325 static int NCR5380_poll_politely(struct Scsi_Host *instance, int reg, int bit, int val, int t)
326 {
327 	NCR5380_local_declare();
328 	int n = 500;		/* At about 8uS a cycle for the cpu access */
329 	unsigned long end = jiffies + t;
330 	int r;
331 
332 	NCR5380_setup(instance);
333 
334 	while( n-- > 0)
335 	{
336 		r = NCR5380_read(reg);
337 		if((r & bit) == val)
338 			return 0;
339 		cpu_relax();
340 	}
341 
342 	/* t time yet ? */
343 	while(time_before(jiffies, end))
344 	{
345 		r = NCR5380_read(reg);
346 		if((r & bit) == val)
347 			return 0;
348 		if(!in_interrupt())
349 			cond_resched();
350 		else
351 			cpu_relax();
352 	}
353 	return -ETIMEDOUT;
354 }
355 
356 static struct {
357 	unsigned char value;
358 	const char *name;
359 } phases[] __maybe_unused = {
360 	{PHASE_DATAOUT, "DATAOUT"},
361 	{PHASE_DATAIN, "DATAIN"},
362 	{PHASE_CMDOUT, "CMDOUT"},
363 	{PHASE_STATIN, "STATIN"},
364 	{PHASE_MSGOUT, "MSGOUT"},
365 	{PHASE_MSGIN, "MSGIN"},
366 	{PHASE_UNKNOWN, "UNKNOWN"}
367 };
368 
369 #if NDEBUG
370 static struct {
371 	unsigned char mask;
372 	const char *name;
373 } signals[] = {
374 	{SR_DBP, "PARITY"},
375 	{SR_RST, "RST"},
376 	{SR_BSY, "BSY"},
377 	{SR_REQ, "REQ"},
378 	{SR_MSG, "MSG"},
379 	{SR_CD, "CD"},
380 	{SR_IO, "IO"},
381 	{SR_SEL, "SEL"},
382 	{0, NULL}
383 },
384 basrs[] = {
385 	{BASR_ATN, "ATN"},
386 	{BASR_ACK, "ACK"},
387 	{0, NULL}
388 },
389 icrs[] = {
390 	{ICR_ASSERT_RST, "ASSERT RST"},
391 	{ICR_ASSERT_ACK, "ASSERT ACK"},
392 	{ICR_ASSERT_BSY, "ASSERT BSY"},
393 	{ICR_ASSERT_SEL, "ASSERT SEL"},
394 	{ICR_ASSERT_ATN, "ASSERT ATN"},
395 	{ICR_ASSERT_DATA, "ASSERT DATA"},
396 	{0, NULL}
397 },
398 mrs[] = {
399 	{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"},
400 	{MR_TARGET, "MODE TARGET"},
401 	{MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"},
402 	{MR_ENABLE_PAR_INTR, "MODE PARITY INTR"},
403 	{MR_MONITOR_BSY, "MODE MONITOR BSY"},
404 	{MR_DMA_MODE, "MODE DMA"},
405 	{MR_ARBITRATE, "MODE ARBITRATION"},
406 	{0, NULL}
407 };
408 
409 /**
410  *	NCR5380_print	-	print scsi bus signals
411  *	@instance:	adapter state to dump
412  *
413  *	Print the SCSI bus signals for debugging purposes
414  *
415  *	Locks: caller holds hostdata lock (not essential)
416  */
417 
418 static void NCR5380_print(struct Scsi_Host *instance)
419 {
420 	NCR5380_local_declare();
421 	unsigned char status, data, basr, mr, icr, i;
422 	NCR5380_setup(instance);
423 
424 	data = NCR5380_read(CURRENT_SCSI_DATA_REG);
425 	status = NCR5380_read(STATUS_REG);
426 	mr = NCR5380_read(MODE_REG);
427 	icr = NCR5380_read(INITIATOR_COMMAND_REG);
428 	basr = NCR5380_read(BUS_AND_STATUS_REG);
429 
430 	printk("STATUS_REG: %02x ", status);
431 	for (i = 0; signals[i].mask; ++i)
432 		if (status & signals[i].mask)
433 			printk(",%s", signals[i].name);
434 	printk("\nBASR: %02x ", basr);
435 	for (i = 0; basrs[i].mask; ++i)
436 		if (basr & basrs[i].mask)
437 			printk(",%s", basrs[i].name);
438 	printk("\nICR: %02x ", icr);
439 	for (i = 0; icrs[i].mask; ++i)
440 		if (icr & icrs[i].mask)
441 			printk(",%s", icrs[i].name);
442 	printk("\nMODE: %02x ", mr);
443 	for (i = 0; mrs[i].mask; ++i)
444 		if (mr & mrs[i].mask)
445 			printk(",%s", mrs[i].name);
446 	printk("\n");
447 }
448 
449 
450 /*
451  *	NCR5380_print_phase	-	show SCSI phase
452  *	@instance: adapter to dump
453  *
454  * 	Print the current SCSI phase for debugging purposes
455  *
456  *	Locks: none
457  */
458 
459 static void NCR5380_print_phase(struct Scsi_Host *instance)
460 {
461 	NCR5380_local_declare();
462 	unsigned char status;
463 	int i;
464 	NCR5380_setup(instance);
465 
466 	status = NCR5380_read(STATUS_REG);
467 	if (!(status & SR_REQ))
468 		printk("scsi%d : REQ not asserted, phase unknown.\n", instance->host_no);
469 	else {
470 		for (i = 0; (phases[i].value != PHASE_UNKNOWN) && (phases[i].value != (status & PHASE_MASK)); ++i);
471 		printk("scsi%d : phase %s\n", instance->host_no, phases[i].name);
472 	}
473 }
474 #endif
475 
476 /*
477  * These need tweaking, and would probably work best as per-device
478  * flags initialized differently for disk, tape, cd, etc devices.
479  * People with broken devices are free to experiment as to what gives
480  * the best results for them.
481  *
482  * USLEEP_SLEEP should be a minimum seek time.
483  *
484  * USLEEP_POLL should be a maximum rotational latency.
485  */
486 #ifndef USLEEP_SLEEP
487 /* 20 ms (reasonable hard disk speed) */
488 #define USLEEP_SLEEP (20*HZ/1000)
489 #endif
490 /* 300 RPM (floppy speed) */
491 #ifndef USLEEP_POLL
492 #define USLEEP_POLL (200*HZ/1000)
493 #endif
494 #ifndef USLEEP_WAITLONG
495 /* RvC: (reasonable time to wait on select error) */
496 #define USLEEP_WAITLONG USLEEP_SLEEP
497 #endif
498 
499 /*
500  * Function : int should_disconnect (unsigned char cmd)
501  *
502  * Purpose : decide whether a command would normally disconnect or
503  *      not, since if it won't disconnect we should go to sleep.
504  *
505  * Input : cmd - opcode of SCSI command
506  *
507  * Returns : DISCONNECT_LONG if we should disconnect for a really long
508  *      time (ie always, sleep, look for REQ active, sleep),
509  *      DISCONNECT_TIME_TO_DATA if we would only disconnect for a normal
510  *      time-to-data delay, DISCONNECT_NONE if this command would return
511  *      immediately.
512  *
513  *      Future sleep algorithms based on time to data can exploit
514  *      something like this so they can differentiate between "normal"
515  *      (ie, read, write, seek) and unusual commands (ie, * format).
516  *
517  * Note : We don't deal with commands that handle an immediate disconnect,
518  *
519  */
520 
521 static int should_disconnect(unsigned char cmd)
522 {
523 	switch (cmd) {
524 	case READ_6:
525 	case WRITE_6:
526 	case SEEK_6:
527 	case READ_10:
528 	case WRITE_10:
529 	case SEEK_10:
530 		return DISCONNECT_TIME_TO_DATA;
531 	case FORMAT_UNIT:
532 	case SEARCH_HIGH:
533 	case SEARCH_LOW:
534 	case SEARCH_EQUAL:
535 		return DISCONNECT_LONG;
536 	default:
537 		return DISCONNECT_NONE;
538 	}
539 }
540 
541 static void NCR5380_set_timer(struct NCR5380_hostdata *hostdata, unsigned long timeout)
542 {
543 	hostdata->time_expires = jiffies + timeout;
544 	schedule_delayed_work(&hostdata->coroutine, timeout);
545 }
546 
547 
548 static int probe_irq __initdata = 0;
549 
550 /**
551  *	probe_intr	-	helper for IRQ autoprobe
552  *	@irq: interrupt number
553  *	@dev_id: unused
554  *	@regs: unused
555  *
556  *	Set a flag to indicate the IRQ in question was received. This is
557  *	used by the IRQ probe code.
558  */
559 
560 static irqreturn_t __init probe_intr(int irq, void *dev_id)
561 {
562 	probe_irq = irq;
563 	return IRQ_HANDLED;
564 }
565 
566 /**
567  *	NCR5380_probe_irq	-	find the IRQ of an NCR5380
568  *	@instance: NCR5380 controller
569  *	@possible: bitmask of ISA IRQ lines
570  *
571  *	Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ
572  *	and then looking to see what interrupt actually turned up.
573  *
574  *	Locks: none, irqs must be enabled on entry
575  */
576 
577 static int __init __maybe_unused NCR5380_probe_irq(struct Scsi_Host *instance,
578 						int possible)
579 {
580 	NCR5380_local_declare();
581 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
582 	unsigned long timeout;
583 	int trying_irqs, i, mask;
584 	NCR5380_setup(instance);
585 
586 	for (trying_irqs = i = 0, mask = 1; i < 16; ++i, mask <<= 1)
587 		if ((mask & possible) && (request_irq(i, &probe_intr, IRQF_DISABLED, "NCR-probe", NULL) == 0))
588 			trying_irqs |= mask;
589 
590 	timeout = jiffies + (250 * HZ / 1000);
591 	probe_irq = SCSI_IRQ_NONE;
592 
593 	/*
594 	 * A interrupt is triggered whenever BSY = false, SEL = true
595 	 * and a bit set in the SELECT_ENABLE_REG is asserted on the
596 	 * SCSI bus.
597 	 *
598 	 * Note that the bus is only driven when the phase control signals
599 	 * (I/O, C/D, and MSG) match those in the TCR, so we must reset that
600 	 * to zero.
601 	 */
602 
603 	NCR5380_write(TARGET_COMMAND_REG, 0);
604 	NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
605 	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
606 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL);
607 
608 	while (probe_irq == SCSI_IRQ_NONE && time_before(jiffies, timeout))
609 		schedule_timeout_uninterruptible(1);
610 
611 	NCR5380_write(SELECT_ENABLE_REG, 0);
612 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
613 
614 	for (i = 0, mask = 1; i < 16; ++i, mask <<= 1)
615 		if (trying_irqs & mask)
616 			free_irq(i, NULL);
617 
618 	return probe_irq;
619 }
620 
621 /**
622  *	NCR58380_print_options	-	show options
623  *	@instance: unused for now
624  *
625  *	Called by probe code indicating the NCR5380 driver options that
626  *	were selected. At some point this will switch to runtime options
627  *	read from the adapter in question
628  *
629  *	Locks: none
630  */
631 
632 static void __init __maybe_unused
633 NCR5380_print_options(struct Scsi_Host *instance)
634 {
635 	printk(" generic options"
636 #ifdef AUTOPROBE_IRQ
637 	       " AUTOPROBE_IRQ"
638 #endif
639 #ifdef AUTOSENSE
640 	       " AUTOSENSE"
641 #endif
642 #ifdef DIFFERENTIAL
643 	       " DIFFERENTIAL"
644 #endif
645 #ifdef REAL_DMA
646 	       " REAL DMA"
647 #endif
648 #ifdef REAL_DMA_POLL
649 	       " REAL DMA POLL"
650 #endif
651 #ifdef PARITY
652 	       " PARITY"
653 #endif
654 #ifdef PSEUDO_DMA
655 	       " PSEUDO DMA"
656 #endif
657 #ifdef UNSAFE
658 	       " UNSAFE "
659 #endif
660 	    );
661 	printk(" USLEEP, USLEEP_POLL=%d USLEEP_SLEEP=%d", USLEEP_POLL, USLEEP_SLEEP);
662 	printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
663 	if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) {
664 		printk(" ncr53c400 release=%d", NCR53C400_PUBLIC_RELEASE);
665 	}
666 }
667 
668 /**
669  *	NCR5380_print_status 	-	dump controller info
670  *	@instance: controller to dump
671  *
672  *	Print commands in the various queues, called from NCR5380_abort
673  *	and NCR5380_debug to aid debugging.
674  *
675  *	Locks: called functions disable irqs
676  */
677 
678 static void NCR5380_print_status(struct Scsi_Host *instance)
679 {
680 	NCR5380_dprint(NDEBUG_ANY, instance);
681 	NCR5380_dprint_phase(NDEBUG_ANY, instance);
682 }
683 
684 /******************************************/
685 /*
686  * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
687  *
688  * *buffer: I/O buffer
689  * **start: if inout == FALSE pointer into buffer where user read should start
690  * offset: current offset
691  * length: length of buffer
692  * hostno: Scsi_Host host_no
693  * inout: TRUE - user is writing; FALSE - user is reading
694  *
695  * Return the number of bytes read from or written
696  */
697 
698 #undef SPRINTF
699 #define SPRINTF(args...) do { if(pos < buffer + length-80) pos += sprintf(pos, ## args); } while(0)
700 static
701 char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length);
702 static
703 char *lprint_command(unsigned char *cmd, char *pos, char *buffer, int len);
704 static
705 char *lprint_opcode(int opcode, char *pos, char *buffer, int length);
706 
707 static int __maybe_unused NCR5380_proc_info(struct Scsi_Host *instance,
708 	char *buffer, char **start, off_t offset, int length, int inout)
709 {
710 	char *pos = buffer;
711 	struct NCR5380_hostdata *hostdata;
712 	Scsi_Cmnd *ptr;
713 
714 	hostdata = (struct NCR5380_hostdata *) instance->hostdata;
715 
716 	if (inout) {		/* Has data been written to the file ? */
717 #ifdef DTC_PUBLIC_RELEASE
718 		dtc_wmaxi = dtc_maxi = 0;
719 #endif
720 #ifdef PAS16_PUBLIC_RELEASE
721 		pas_wmaxi = pas_maxi = 0;
722 #endif
723 		return (-ENOSYS);	/* Currently this is a no-op */
724 	}
725 	SPRINTF("NCR5380 core release=%d.   ", NCR5380_PUBLIC_RELEASE);
726 	if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400)
727 		SPRINTF("ncr53c400 release=%d.  ", NCR53C400_PUBLIC_RELEASE);
728 #ifdef DTC_PUBLIC_RELEASE
729 	SPRINTF("DTC 3180/3280 release %d", DTC_PUBLIC_RELEASE);
730 #endif
731 #ifdef T128_PUBLIC_RELEASE
732 	SPRINTF("T128 release %d", T128_PUBLIC_RELEASE);
733 #endif
734 #ifdef GENERIC_NCR5380_PUBLIC_RELEASE
735 	SPRINTF("Generic5380 release %d", GENERIC_NCR5380_PUBLIC_RELEASE);
736 #endif
737 #ifdef PAS16_PUBLIC_RELEASE
738 	SPRINTF("PAS16 release=%d", PAS16_PUBLIC_RELEASE);
739 #endif
740 
741 	SPRINTF("\nBase Addr: 0x%05lX    ", (long) instance->base);
742 	SPRINTF("io_port: %04x      ", (int) instance->io_port);
743 	if (instance->irq == SCSI_IRQ_NONE)
744 		SPRINTF("IRQ: None.\n");
745 	else
746 		SPRINTF("IRQ: %d.\n", instance->irq);
747 
748 #ifdef DTC_PUBLIC_RELEASE
749 	SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", dtc_wmaxi, dtc_maxi);
750 #endif
751 #ifdef PAS16_PUBLIC_RELEASE
752 	SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", pas_wmaxi, pas_maxi);
753 #endif
754 	spin_lock_irq(instance->host_lock);
755 	if (!hostdata->connected)
756 		SPRINTF("scsi%d: no currently connected command\n", instance->host_no);
757 	else
758 		pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, pos, buffer, length);
759 	SPRINTF("scsi%d: issue_queue\n", instance->host_no);
760 	for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
761 		pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
762 
763 	SPRINTF("scsi%d: disconnected_queue\n", instance->host_no);
764 	for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
765 		pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
766 	spin_unlock_irq(instance->host_lock);
767 
768 	*start = buffer;
769 	if (pos - buffer < offset)
770 		return 0;
771 	else if (pos - buffer - offset < length)
772 		return pos - buffer - offset;
773 	return length;
774 }
775 
776 static char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length)
777 {
778 	SPRINTF("scsi%d : destination target %d, lun %d\n", cmd->device->host->host_no, cmd->device->id, cmd->device->lun);
779 	SPRINTF("        command = ");
780 	pos = lprint_command(cmd->cmnd, pos, buffer, length);
781 	return (pos);
782 }
783 
784 static char *lprint_command(unsigned char *command, char *pos, char *buffer, int length)
785 {
786 	int i, s;
787 	pos = lprint_opcode(command[0], pos, buffer, length);
788 	for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
789 		SPRINTF("%02x ", command[i]);
790 	SPRINTF("\n");
791 	return (pos);
792 }
793 
794 static char *lprint_opcode(int opcode, char *pos, char *buffer, int length)
795 {
796 	SPRINTF("%2d (0x%02x)", opcode, opcode);
797 	return (pos);
798 }
799 
800 
801 /**
802  *	NCR5380_init	-	initialise an NCR5380
803  *	@instance: adapter to configure
804  *	@flags: control flags
805  *
806  *	Initializes *instance and corresponding 5380 chip,
807  *      with flags OR'd into the initial flags value.
808  *
809  *	Notes : I assume that the host, hostno, and id bits have been
810  *      set correctly.  I don't care about the irq and other fields.
811  *
812  *	Returns 0 for success
813  *
814  *	Locks: interrupts must be enabled when we are called
815  */
816 
817 static int __devinit NCR5380_init(struct Scsi_Host *instance, int flags)
818 {
819 	NCR5380_local_declare();
820 	int i, pass;
821 	unsigned long timeout;
822 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
823 
824 	if(in_interrupt())
825 		printk(KERN_ERR "NCR5380_init called with interrupts off!\n");
826 	/*
827 	 * On NCR53C400 boards, NCR5380 registers are mapped 8 past
828 	 * the base address.
829 	 */
830 
831 #ifdef NCR53C400
832 	if (flags & FLAG_NCR53C400)
833 		instance->NCR5380_instance_name += NCR53C400_address_adjust;
834 #endif
835 
836 	NCR5380_setup(instance);
837 
838 	hostdata->aborted = 0;
839 	hostdata->id_mask = 1 << instance->this_id;
840 	for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
841 		if (i > hostdata->id_mask)
842 			hostdata->id_higher_mask |= i;
843 	for (i = 0; i < 8; ++i)
844 		hostdata->busy[i] = 0;
845 #ifdef REAL_DMA
846 	hostdata->dmalen = 0;
847 #endif
848 	hostdata->targets_present = 0;
849 	hostdata->connected = NULL;
850 	hostdata->issue_queue = NULL;
851 	hostdata->disconnected_queue = NULL;
852 
853 	INIT_DELAYED_WORK(&hostdata->coroutine, NCR5380_main);
854 
855 #ifdef NCR5380_STATS
856 	for (i = 0; i < 8; ++i) {
857 		hostdata->time_read[i] = 0;
858 		hostdata->time_write[i] = 0;
859 		hostdata->bytes_read[i] = 0;
860 		hostdata->bytes_write[i] = 0;
861 	}
862 	hostdata->timebase = 0;
863 	hostdata->pendingw = 0;
864 	hostdata->pendingr = 0;
865 #endif
866 
867 	/* The CHECK code seems to break the 53C400. Will check it later maybe */
868 	if (flags & FLAG_NCR53C400)
869 		hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags;
870 	else
871 		hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags;
872 
873 	hostdata->host = instance;
874 	hostdata->time_expires = 0;
875 
876 #ifndef AUTOSENSE
877 	if ((instance->cmd_per_lun > 1) || instance->can_queue > 1)
878 		    printk(KERN_WARNING "scsi%d : WARNING : support for multiple outstanding commands enabled\n" "         without AUTOSENSE option, contingent allegiance conditions may\n"
879 		    	   "         be incorrectly cleared.\n", instance->host_no);
880 #endif				/* def AUTOSENSE */
881 
882 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
883 	NCR5380_write(MODE_REG, MR_BASE);
884 	NCR5380_write(TARGET_COMMAND_REG, 0);
885 	NCR5380_write(SELECT_ENABLE_REG, 0);
886 
887 #ifdef NCR53C400
888 	if (hostdata->flags & FLAG_NCR53C400) {
889 		NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE);
890 	}
891 #endif
892 
893 	/*
894 	 * Detect and correct bus wedge problems.
895 	 *
896 	 * If the system crashed, it may have crashed in a state
897 	 * where a SCSI command was still executing, and the
898 	 * SCSI bus is not in a BUS FREE STATE.
899 	 *
900 	 * If this is the case, we'll try to abort the currently
901 	 * established nexus which we know nothing about, and that
902 	 * failing, do a hard reset of the SCSI bus
903 	 */
904 
905 	for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
906 		switch (pass) {
907 		case 1:
908 		case 3:
909 		case 5:
910 			printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no);
911 			timeout = jiffies + 5 * HZ;
912 			NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ);
913 			break;
914 		case 2:
915 			printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no);
916 			do_abort(instance);
917 			break;
918 		case 4:
919 			printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no);
920 			do_reset(instance);
921 			break;
922 		case 6:
923 			printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no);
924 			return -ENXIO;
925 		}
926 	}
927 	return 0;
928 }
929 
930 /**
931  *	NCR5380_exit	-	remove an NCR5380
932  *	@instance: adapter to remove
933  */
934 
935 static void NCR5380_exit(struct Scsi_Host *instance)
936 {
937 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
938 
939 	cancel_delayed_work_sync(&hostdata->coroutine);
940 }
941 
942 /**
943  *	NCR5380_queue_command 		-	queue a command
944  *	@cmd: SCSI command
945  *	@done: completion handler
946  *
947  *      cmd is added to the per instance issue_queue, with minor
948  *      twiddling done to the host specific fields of cmd.  If the
949  *      main coroutine is not running, it is restarted.
950  *
951  *	Locks: host lock taken by caller
952  */
953 
954 static int NCR5380_queue_command_lck(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *))
955 {
956 	struct Scsi_Host *instance = cmd->device->host;
957 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
958 	Scsi_Cmnd *tmp;
959 
960 #if (NDEBUG & NDEBUG_NO_WRITE)
961 	switch (cmd->cmnd[0]) {
962 	case WRITE_6:
963 	case WRITE_10:
964 		printk("scsi%d : WRITE attempted with NO_WRITE debugging flag set\n", instance->host_no);
965 		cmd->result = (DID_ERROR << 16);
966 		done(cmd);
967 		return 0;
968 	}
969 #endif				/* (NDEBUG & NDEBUG_NO_WRITE) */
970 
971 #ifdef NCR5380_STATS
972 	switch (cmd->cmnd[0]) {
973 		case WRITE:
974 		case WRITE_6:
975 		case WRITE_10:
976 			hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
977 			hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);
978 			hostdata->pendingw++;
979 			break;
980 		case READ:
981 		case READ_6:
982 		case READ_10:
983 			hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
984 			hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);
985 			hostdata->pendingr++;
986 			break;
987 	}
988 #endif
989 
990 	/*
991 	 * We use the host_scribble field as a pointer to the next command
992 	 * in a queue
993 	 */
994 
995 	cmd->host_scribble = NULL;
996 	cmd->scsi_done = done;
997 	cmd->result = 0;
998 
999 	/*
1000 	 * Insert the cmd into the issue queue. Note that REQUEST SENSE
1001 	 * commands are added to the head of the queue since any command will
1002 	 * clear the contingent allegiance condition that exists and the
1003 	 * sense data is only guaranteed to be valid while the condition exists.
1004 	 */
1005 
1006 	if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
1007 		LIST(cmd, hostdata->issue_queue);
1008 		cmd->host_scribble = (unsigned char *) hostdata->issue_queue;
1009 		hostdata->issue_queue = cmd;
1010 	} else {
1011 		for (tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp->host_scribble; tmp = (Scsi_Cmnd *) tmp->host_scribble);
1012 		LIST(cmd, tmp);
1013 		tmp->host_scribble = (unsigned char *) cmd;
1014 	}
1015 	dprintk(NDEBUG_QUEUES, ("scsi%d : command added to %s of queue\n", instance->host_no, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"));
1016 
1017 	/* Run the coroutine if it isn't already running. */
1018 	/* Kick off command processing */
1019 	schedule_delayed_work(&hostdata->coroutine, 0);
1020 	return 0;
1021 }
1022 
1023 static DEF_SCSI_QCMD(NCR5380_queue_command)
1024 
1025 /**
1026  *	NCR5380_main	-	NCR state machines
1027  *
1028  *	NCR5380_main is a coroutine that runs as long as more work can
1029  *      be done on the NCR5380 host adapters in a system.  Both
1030  *      NCR5380_queue_command() and NCR5380_intr() will try to start it
1031  *      in case it is not running.
1032  *
1033  *	Locks: called as its own thread with no locks held. Takes the
1034  *	host lock and called routines may take the isa dma lock.
1035  */
1036 
1037 static void NCR5380_main(struct work_struct *work)
1038 {
1039 	struct NCR5380_hostdata *hostdata =
1040 		container_of(work, struct NCR5380_hostdata, coroutine.work);
1041 	struct Scsi_Host *instance = hostdata->host;
1042 	Scsi_Cmnd *tmp, *prev;
1043 	int done;
1044 
1045 	spin_lock_irq(instance->host_lock);
1046 	do {
1047 		/* Lock held here */
1048 		done = 1;
1049 		if (!hostdata->connected && !hostdata->selecting) {
1050 			dprintk(NDEBUG_MAIN, ("scsi%d : not connected\n", instance->host_no));
1051 			/*
1052 			 * Search through the issue_queue for a command destined
1053 			 * for a target that's not busy.
1054 			 */
1055 			for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
1056 			{
1057 				if (prev != tmp)
1058 					dprintk(NDEBUG_LISTS, ("MAIN tmp=%p   target=%d   busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun));
1059 				/*  When we find one, remove it from the issue queue. */
1060 				if (!(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))) {
1061 					if (prev) {
1062 						REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
1063 						prev->host_scribble = tmp->host_scribble;
1064 					} else {
1065 						REMOVE(-1, hostdata->issue_queue, tmp, tmp->host_scribble);
1066 						hostdata->issue_queue = (Scsi_Cmnd *) tmp->host_scribble;
1067 					}
1068 					tmp->host_scribble = NULL;
1069 
1070 					/*
1071 					 * Attempt to establish an I_T_L nexus here.
1072 					 * On success, instance->hostdata->connected is set.
1073 					 * On failure, we must add the command back to the
1074 					 *   issue queue so we can keep trying.
1075 					 */
1076 					dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main() : command for target %d lun %d removed from issue_queue\n", instance->host_no, tmp->target, tmp->lun));
1077 
1078 					/*
1079 					 * A successful selection is defined as one that
1080 					 * leaves us with the command connected and
1081 					 * in hostdata->connected, OR has terminated the
1082 					 * command.
1083 					 *
1084 					 * With successful commands, we fall through
1085 					 * and see if we can do an information transfer,
1086 					 * with failures we will restart.
1087 					 */
1088 					hostdata->selecting = NULL;
1089 					/* RvC: have to preset this to indicate a new command is being performed */
1090 
1091 					if (!NCR5380_select(instance, tmp,
1092 							    /*
1093 							     * REQUEST SENSE commands are issued without tagged
1094 							     * queueing, even on SCSI-II devices because the
1095 							     * contingent allegiance condition exists for the
1096 							     * entire unit.
1097 							     */
1098 							    (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1099 						break;
1100 					} else {
1101 						LIST(tmp, hostdata->issue_queue);
1102 						tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1103 						hostdata->issue_queue = tmp;
1104 						done = 0;
1105 						dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main(): select() failed, returned to issue_queue\n", instance->host_no));
1106 					}
1107 					/* lock held here still */
1108 				}	/* if target/lun is not busy */
1109 			}	/* for */
1110 			/* exited locked */
1111 		}	/* if (!hostdata->connected) */
1112 		if (hostdata->selecting) {
1113 			tmp = (Scsi_Cmnd *) hostdata->selecting;
1114 			/* Selection will drop and retake the lock */
1115 			if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1116 				/* Ok ?? */
1117 			} else {
1118 				/* RvC: device failed, so we wait a long time
1119 				   this is needed for Mustek scanners, that
1120 				   do not respond to commands immediately
1121 				   after a scan */
1122 				printk(KERN_DEBUG "scsi%d: device %d did not respond in time\n", instance->host_no, tmp->device->id);
1123 				LIST(tmp, hostdata->issue_queue);
1124 				tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1125 				hostdata->issue_queue = tmp;
1126 				NCR5380_set_timer(hostdata, USLEEP_WAITLONG);
1127 			}
1128 		}	/* if hostdata->selecting */
1129 		if (hostdata->connected
1130 #ifdef REAL_DMA
1131 		    && !hostdata->dmalen
1132 #endif
1133 		    && (!hostdata->time_expires || time_before_eq(hostdata->time_expires, jiffies))
1134 		    ) {
1135 			dprintk(NDEBUG_MAIN, ("scsi%d : main() : performing information transfer\n", instance->host_no));
1136 			NCR5380_information_transfer(instance);
1137 			dprintk(NDEBUG_MAIN, ("scsi%d : main() : done set false\n", instance->host_no));
1138 			done = 0;
1139 		} else
1140 			break;
1141 	} while (!done);
1142 
1143 	spin_unlock_irq(instance->host_lock);
1144 }
1145 
1146 #ifndef DONT_USE_INTR
1147 
1148 /**
1149  * 	NCR5380_intr	-	generic NCR5380 irq handler
1150  *	@irq: interrupt number
1151  *	@dev_id: device info
1152  *
1153  *	Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1154  *      from the disconnected queue, and restarting NCR5380_main()
1155  *      as required.
1156  *
1157  *	Locks: takes the needed instance locks
1158  */
1159 
1160 static irqreturn_t NCR5380_intr(int dummy, void *dev_id)
1161 {
1162 	NCR5380_local_declare();
1163 	struct Scsi_Host *instance = dev_id;
1164 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1165 	int done;
1166 	unsigned char basr;
1167 	unsigned long flags;
1168 
1169 	dprintk(NDEBUG_INTR, ("scsi : NCR5380 irq %d triggered\n",
1170 		instance->irq));
1171 
1172 	do {
1173 		done = 1;
1174 		spin_lock_irqsave(instance->host_lock, flags);
1175 		/* Look for pending interrupts */
1176 		NCR5380_setup(instance);
1177 		basr = NCR5380_read(BUS_AND_STATUS_REG);
1178 		/* XXX dispatch to appropriate routine if found and done=0 */
1179 		if (basr & BASR_IRQ) {
1180 			NCR5380_dprint(NDEBUG_INTR, instance);
1181 			if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1182 				done = 0;
1183 				dprintk(NDEBUG_INTR, ("scsi%d : SEL interrupt\n", instance->host_no));
1184 				NCR5380_reselect(instance);
1185 				(void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1186 			} else if (basr & BASR_PARITY_ERROR) {
1187 				dprintk(NDEBUG_INTR, ("scsi%d : PARITY interrupt\n", instance->host_no));
1188 				(void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1189 			} else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1190 				dprintk(NDEBUG_INTR, ("scsi%d : RESET interrupt\n", instance->host_no));
1191 				(void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1192 			} else {
1193 #if defined(REAL_DMA)
1194 				/*
1195 				 * We should only get PHASE MISMATCH and EOP interrupts
1196 				 * if we have DMA enabled, so do a sanity check based on
1197 				 * the current setting of the MODE register.
1198 				 */
1199 
1200 				if ((NCR5380_read(MODE_REG) & MR_DMA) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) {
1201 					int transferred;
1202 
1203 					if (!hostdata->connected)
1204 						panic("scsi%d : received end of DMA interrupt with no connected cmd\n", instance->hostno);
1205 
1206 					transferred = (hostdata->dmalen - NCR5380_dma_residual(instance));
1207 					hostdata->connected->SCp.this_residual -= transferred;
1208 					hostdata->connected->SCp.ptr += transferred;
1209 					hostdata->dmalen = 0;
1210 
1211 					(void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1212 
1213 					/* FIXME: we need to poll briefly then defer a workqueue task ! */
1214 					NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2*HZ);
1215 
1216 					NCR5380_write(MODE_REG, MR_BASE);
1217 					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1218 				}
1219 #else
1220 				dprintk(NDEBUG_INTR, ("scsi : unknown interrupt, BASR 0x%X, MR 0x%X, SR 0x%x\n", basr, NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)));
1221 				(void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1222 #endif
1223 			}
1224 		}	/* if BASR_IRQ */
1225 		spin_unlock_irqrestore(instance->host_lock, flags);
1226 		if(!done)
1227 			schedule_delayed_work(&hostdata->coroutine, 0);
1228 	} while (!done);
1229 	return IRQ_HANDLED;
1230 }
1231 
1232 #endif
1233 
1234 /**
1235  *	collect_stats		-	collect stats on a scsi command
1236  *	@hostdata: adapter
1237  *	@cmd: command being issued
1238  *
1239  *	Update the statistical data by parsing the command in question
1240  */
1241 
1242 static void collect_stats(struct NCR5380_hostdata *hostdata, Scsi_Cmnd * cmd)
1243 {
1244 #ifdef NCR5380_STATS
1245 	switch (cmd->cmnd[0]) {
1246 	case WRITE:
1247 	case WRITE_6:
1248 	case WRITE_10:
1249 		hostdata->time_write[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1250 		hostdata->pendingw--;
1251 		break;
1252 	case READ:
1253 	case READ_6:
1254 	case READ_10:
1255 		hostdata->time_read[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1256 		hostdata->pendingr--;
1257 		break;
1258 	}
1259 #endif
1260 }
1261 
1262 
1263 /*
1264  * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1265  *      int tag);
1266  *
1267  * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1268  *      including ARBITRATION, SELECTION, and initial message out for
1269  *      IDENTIFY and queue messages.
1270  *
1271  * Inputs : instance - instantiation of the 5380 driver on which this
1272  *      target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1273  *      new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1274  *      the command that is presently connected.
1275  *
1276  * Returns : -1 if selection could not execute for some reason,
1277  *      0 if selection succeeded or failed because the target
1278  *      did not respond.
1279  *
1280  * Side effects :
1281  *      If bus busy, arbitration failed, etc, NCR5380_select() will exit
1282  *              with registers as they should have been on entry - ie
1283  *              SELECT_ENABLE will be set appropriately, the NCR5380
1284  *              will cease to drive any SCSI bus signals.
1285  *
1286  *      If successful : I_T_L or I_T_L_Q nexus will be established,
1287  *              instance->connected will be set to cmd.
1288  *              SELECT interrupt will be disabled.
1289  *
1290  *      If failed (no target) : cmd->scsi_done() will be called, and the
1291  *              cmd->result host byte set to DID_BAD_TARGET.
1292  *
1293  *	Locks: caller holds hostdata lock in IRQ mode
1294  */
1295 
1296 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag)
1297 {
1298 	NCR5380_local_declare();
1299 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1300 	unsigned char tmp[3], phase;
1301 	unsigned char *data;
1302 	int len;
1303 	unsigned long timeout;
1304 	unsigned char value;
1305 	int err;
1306 	NCR5380_setup(instance);
1307 
1308 	if (hostdata->selecting)
1309 		goto part2;
1310 
1311 	hostdata->restart_select = 0;
1312 
1313 	NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1314 	dprintk(NDEBUG_ARBITRATION, ("scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id));
1315 
1316 	/*
1317 	 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1318 	 * data bus during SELECTION.
1319 	 */
1320 
1321 	NCR5380_write(TARGET_COMMAND_REG, 0);
1322 
1323 	/*
1324 	 * Start arbitration.
1325 	 */
1326 
1327 	NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1328 	NCR5380_write(MODE_REG, MR_ARBITRATE);
1329 
1330 
1331 	/* We can be relaxed here, interrupts are on, we are
1332 	   in workqueue context, the birds are singing in the trees */
1333 	spin_unlock_irq(instance->host_lock);
1334 	err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ);
1335 	spin_lock_irq(instance->host_lock);
1336 	if (err < 0) {
1337 		printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__);
1338 		NCR5380_write(MODE_REG, MR_BASE);
1339 		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1340 		goto failed;
1341 	}
1342 
1343 	dprintk(NDEBUG_ARBITRATION, ("scsi%d : arbitration complete\n", instance->host_no));
1344 
1345 	/*
1346 	 * The arbitration delay is 2.2us, but this is a minimum and there is
1347 	 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1348 	 * the integral nature of udelay().
1349 	 *
1350 	 */
1351 
1352 	udelay(3);
1353 
1354 	/* Check for lost arbitration */
1355 	if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1356 		NCR5380_write(MODE_REG, MR_BASE);
1357 		dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no));
1358 		goto failed;
1359 	}
1360 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL);
1361 
1362 	if (!(hostdata->flags & FLAG_DTC3181E) &&
1363 	    /* RvC: DTC3181E has some trouble with this
1364 	     *      so we simply removed it. Seems to work with
1365 	     *      only Mustek scanner attached
1366 	     */
1367 	    (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1368 		NCR5380_write(MODE_REG, MR_BASE);
1369 		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1370 		dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no));
1371 		goto failed;
1372 	}
1373 	/*
1374 	 * Again, bus clear + bus settle time is 1.2us, however, this is
1375 	 * a minimum so we'll udelay ceil(1.2)
1376 	 */
1377 
1378 	udelay(2);
1379 
1380 	dprintk(NDEBUG_ARBITRATION, ("scsi%d : won arbitration\n", instance->host_no));
1381 
1382 	/*
1383 	 * Now that we have won arbitration, start Selection process, asserting
1384 	 * the host and target ID's on the SCSI bus.
1385 	 */
1386 
1387 	NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << scmd_id(cmd))));
1388 
1389 	/*
1390 	 * Raise ATN while SEL is true before BSY goes false from arbitration,
1391 	 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1392 	 * phase immediately after selection.
1393 	 */
1394 
1395 	NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1396 	NCR5380_write(MODE_REG, MR_BASE);
1397 
1398 	/*
1399 	 * Reselect interrupts must be turned off prior to the dropping of BSY,
1400 	 * otherwise we will trigger an interrupt.
1401 	 */
1402 	NCR5380_write(SELECT_ENABLE_REG, 0);
1403 
1404 	/*
1405 	 * The initiator shall then wait at least two deskew delays and release
1406 	 * the BSY signal.
1407 	 */
1408 	udelay(1);		/* wingel -- wait two bus deskew delay >2*45ns */
1409 
1410 	/* Reset BSY */
1411 	NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1412 
1413 	/*
1414 	 * Something weird happens when we cease to drive BSY - looks
1415 	 * like the board/chip is letting us do another read before the
1416 	 * appropriate propagation delay has expired, and we're confusing
1417 	 * a BSY signal from ourselves as the target's response to SELECTION.
1418 	 *
1419 	 * A small delay (the 'C++' frontend breaks the pipeline with an
1420 	 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1421 	 * tighter 'C' code breaks and requires this) solves the problem -
1422 	 * the 1 us delay is arbitrary, and only used because this delay will
1423 	 * be the same on other platforms and since it works here, it should
1424 	 * work there.
1425 	 *
1426 	 * wingel suggests that this could be due to failing to wait
1427 	 * one deskew delay.
1428 	 */
1429 
1430 	udelay(1);
1431 
1432 	dprintk(NDEBUG_SELECTION, ("scsi%d : selecting target %d\n", instance->host_no, scmd_id(cmd)));
1433 
1434 	/*
1435 	 * The SCSI specification calls for a 250 ms timeout for the actual
1436 	 * selection.
1437 	 */
1438 
1439 	timeout = jiffies + (250 * HZ / 1000);
1440 
1441 	/*
1442 	 * XXX very interesting - we're seeing a bounce where the BSY we
1443 	 * asserted is being reflected / still asserted (propagation delay?)
1444 	 * and it's detecting as true.  Sigh.
1445 	 */
1446 
1447 	hostdata->select_time = 0;	/* we count the clock ticks at which we polled */
1448 	hostdata->selecting = cmd;
1449 
1450 part2:
1451 	/* RvC: here we enter after a sleeping period, or immediately after
1452 	   execution of part 1
1453 	   we poll only once ech clock tick */
1454 	value = NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO);
1455 
1456 	if (!value && (hostdata->select_time < HZ/4)) {
1457 		/* RvC: we still must wait for a device response */
1458 		hostdata->select_time++;	/* after 25 ticks the device has failed */
1459 		NCR5380_set_timer(hostdata, 1);
1460 		return 0;	/* RvC: we return here with hostdata->selecting set,
1461 				   to go to sleep */
1462 	}
1463 
1464 	hostdata->selecting = NULL;/* clear this pointer, because we passed the
1465 					   waiting period */
1466 	if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1467 		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1468 		NCR5380_reselect(instance);
1469 		printk("scsi%d : reselection after won arbitration?\n", instance->host_no);
1470 		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1471 		return -1;
1472 	}
1473 	/*
1474 	 * No less than two deskew delays after the initiator detects the
1475 	 * BSY signal is true, it shall release the SEL signal and may
1476 	 * change the DATA BUS.                                     -wingel
1477 	 */
1478 
1479 	udelay(1);
1480 
1481 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1482 
1483 	if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1484 		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1485 		if (hostdata->targets_present & (1 << scmd_id(cmd))) {
1486 			printk(KERN_DEBUG "scsi%d : weirdness\n", instance->host_no);
1487 			if (hostdata->restart_select)
1488 				printk(KERN_DEBUG "\trestart select\n");
1489 			NCR5380_dprint(NDEBUG_SELECTION, instance);
1490 			NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1491 			return -1;
1492 		}
1493 		cmd->result = DID_BAD_TARGET << 16;
1494 		collect_stats(hostdata, cmd);
1495 		cmd->scsi_done(cmd);
1496 		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1497 		dprintk(NDEBUG_SELECTION, ("scsi%d : target did not respond within 250ms\n", instance->host_no));
1498 		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1499 		return 0;
1500 	}
1501 	hostdata->targets_present |= (1 << scmd_id(cmd));
1502 
1503 	/*
1504 	 * Since we followed the SCSI spec, and raised ATN while SEL
1505 	 * was true but before BSY was false during selection, the information
1506 	 * transfer phase should be a MESSAGE OUT phase so that we can send the
1507 	 * IDENTIFY message.
1508 	 *
1509 	 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1510 	 * message (2 bytes) with a tag ID that we increment with every command
1511 	 * until it wraps back to 0.
1512 	 *
1513 	 * XXX - it turns out that there are some broken SCSI-II devices,
1514 	 *       which claim to support tagged queuing but fail when more than
1515 	 *       some number of commands are issued at once.
1516 	 */
1517 
1518 	/* Wait for start of REQ/ACK handshake */
1519 
1520 	spin_unlock_irq(instance->host_lock);
1521 	err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
1522 	spin_lock_irq(instance->host_lock);
1523 
1524 	if(err) {
1525 		printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__);
1526 		NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1527 		goto failed;
1528 	}
1529 
1530 	dprintk(NDEBUG_SELECTION, ("scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id));
1531 	tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun);
1532 
1533 	len = 1;
1534 	cmd->tag = 0;
1535 
1536 	/* Send message(s) */
1537 	data = tmp;
1538 	phase = PHASE_MSGOUT;
1539 	NCR5380_transfer_pio(instance, &phase, &len, &data);
1540 	dprintk(NDEBUG_SELECTION, ("scsi%d : nexus established.\n", instance->host_no));
1541 	/* XXX need to handle errors here */
1542 	hostdata->connected = cmd;
1543 	hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1544 
1545 	initialize_SCp(cmd);
1546 
1547 	return 0;
1548 
1549 	/* Selection failed */
1550 failed:
1551 	return -1;
1552 
1553 }
1554 
1555 /*
1556  * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1557  *      unsigned char *phase, int *count, unsigned char **data)
1558  *
1559  * Purpose : transfers data in given phase using polled I/O
1560  *
1561  * Inputs : instance - instance of driver, *phase - pointer to
1562  *      what phase is expected, *count - pointer to number of
1563  *      bytes to transfer, **data - pointer to data pointer.
1564  *
1565  * Returns : -1 when different phase is entered without transferring
1566  *      maximum number of bytes, 0 if all bytes or transferred or exit
1567  *      is in same phase.
1568  *
1569  *      Also, *phase, *count, *data are modified in place.
1570  *
1571  * XXX Note : handling for bus free may be useful.
1572  */
1573 
1574 /*
1575  * Note : this code is not as quick as it could be, however it
1576  * IS 100% reliable, and for the actual data transfer where speed
1577  * counts, we will always do a pseudo DMA or DMA transfer.
1578  */
1579 
1580 static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1581 	NCR5380_local_declare();
1582 	unsigned char p = *phase, tmp;
1583 	int c = *count;
1584 	unsigned char *d = *data;
1585 	/*
1586 	 *      RvC: some administrative data to process polling time
1587 	 */
1588 	int break_allowed = 0;
1589 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1590 	NCR5380_setup(instance);
1591 
1592 	if (!(p & SR_IO))
1593 		dprintk(NDEBUG_PIO, ("scsi%d : pio write %d bytes\n", instance->host_no, c));
1594 	else
1595 		dprintk(NDEBUG_PIO, ("scsi%d : pio read %d bytes\n", instance->host_no, c));
1596 
1597 	/*
1598 	 * The NCR5380 chip will only drive the SCSI bus when the
1599 	 * phase specified in the appropriate bits of the TARGET COMMAND
1600 	 * REGISTER match the STATUS REGISTER
1601 	 */
1602 
1603 	 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1604 
1605 	/* RvC: don't know if this is necessary, but other SCSI I/O is short
1606 	 *      so breaks are not necessary there
1607 	 */
1608 	if ((p == PHASE_DATAIN) || (p == PHASE_DATAOUT)) {
1609 		break_allowed = 1;
1610 	}
1611 	do {
1612 		/*
1613 		 * Wait for assertion of REQ, after which the phase bits will be
1614 		 * valid
1615 		 */
1616 
1617 		/* RvC: we simply poll once, after that we stop temporarily
1618 		 *      and let the device buffer fill up
1619 		 *      if breaking is not allowed, we keep polling as long as needed
1620 		 */
1621 
1622 		/* FIXME */
1623 		while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ) && !break_allowed);
1624 		if (!(tmp & SR_REQ)) {
1625 			/* timeout condition */
1626 			NCR5380_set_timer(hostdata, USLEEP_SLEEP);
1627 			break;
1628 		}
1629 
1630 		dprintk(NDEBUG_HANDSHAKE, ("scsi%d : REQ detected\n", instance->host_no));
1631 
1632 		/* Check for phase mismatch */
1633 		if ((tmp & PHASE_MASK) != p) {
1634 			dprintk(NDEBUG_HANDSHAKE, ("scsi%d : phase mismatch\n", instance->host_no));
1635 			NCR5380_dprint_phase(NDEBUG_HANDSHAKE, instance);
1636 			break;
1637 		}
1638 		/* Do actual transfer from SCSI bus to / from memory */
1639 		if (!(p & SR_IO))
1640 			NCR5380_write(OUTPUT_DATA_REG, *d);
1641 		else
1642 			*d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1643 
1644 		++d;
1645 
1646 		/*
1647 		 * The SCSI standard suggests that in MSGOUT phase, the initiator
1648 		 * should drop ATN on the last byte of the message phase
1649 		 * after REQ has been asserted for the handshake but before
1650 		 * the initiator raises ACK.
1651 		 */
1652 
1653 		if (!(p & SR_IO)) {
1654 			if (!((p & SR_MSG) && c > 1)) {
1655 				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1656 				NCR5380_dprint(NDEBUG_PIO, instance);
1657 				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1658 			} else {
1659 				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1660 				NCR5380_dprint(NDEBUG_PIO, instance);
1661 				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1662 			}
1663 		} else {
1664 			NCR5380_dprint(NDEBUG_PIO, instance);
1665 			NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1666 		}
1667 
1668 		/* FIXME - if this fails bus reset ?? */
1669 		NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 5*HZ);
1670 		dprintk(NDEBUG_HANDSHAKE, ("scsi%d : req false, handshake complete\n", instance->host_no));
1671 
1672 /*
1673  * We have several special cases to consider during REQ/ACK handshaking :
1674  * 1.  We were in MSGOUT phase, and we are on the last byte of the
1675  *      message.  ATN must be dropped as ACK is dropped.
1676  *
1677  * 2.  We are in a MSGIN phase, and we are on the last byte of the
1678  *      message.  We must exit with ACK asserted, so that the calling
1679  *      code may raise ATN before dropping ACK to reject the message.
1680  *
1681  * 3.  ACK and ATN are clear and the target may proceed as normal.
1682  */
1683 		if (!(p == PHASE_MSGIN && c == 1)) {
1684 			if (p == PHASE_MSGOUT && c > 1)
1685 				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1686 			else
1687 				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1688 		}
1689 	} while (--c);
1690 
1691 	dprintk(NDEBUG_PIO, ("scsi%d : residual %d\n", instance->host_no, c));
1692 
1693 	*count = c;
1694 	*data = d;
1695 	tmp = NCR5380_read(STATUS_REG);
1696 	if (tmp & SR_REQ)
1697 		*phase = tmp & PHASE_MASK;
1698 	else
1699 		*phase = PHASE_UNKNOWN;
1700 
1701 	if (!c || (*phase == p))
1702 		return 0;
1703 	else
1704 		return -1;
1705 }
1706 
1707 /**
1708  *	do_reset	-	issue a reset command
1709  *	@host: adapter to reset
1710  *
1711  *	Issue a reset sequence to the NCR5380 and try and get the bus
1712  *	back into sane shape.
1713  *
1714  *	Locks: caller holds queue lock
1715  */
1716 
1717 static void do_reset(struct Scsi_Host *host) {
1718 	NCR5380_local_declare();
1719 	NCR5380_setup(host);
1720 
1721 	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
1722 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
1723 	udelay(25);
1724 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1725 }
1726 
1727 /*
1728  * Function : do_abort (Scsi_Host *host)
1729  *
1730  * Purpose : abort the currently established nexus.  Should only be
1731  *      called from a routine which can drop into a
1732  *
1733  * Returns : 0 on success, -1 on failure.
1734  *
1735  * Locks: queue lock held by caller
1736  *	FIXME: sort this out and get new_eh running
1737  */
1738 
1739 static int do_abort(struct Scsi_Host *host) {
1740 	NCR5380_local_declare();
1741 	unsigned char *msgptr, phase, tmp;
1742 	int len;
1743 	int rc;
1744 	NCR5380_setup(host);
1745 
1746 
1747 	/* Request message out phase */
1748 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1749 
1750 	/*
1751 	 * Wait for the target to indicate a valid phase by asserting
1752 	 * REQ.  Once this happens, we'll have either a MSGOUT phase
1753 	 * and can immediately send the ABORT message, or we'll have some
1754 	 * other phase and will have to source/sink data.
1755 	 *
1756 	 * We really don't care what value was on the bus or what value
1757 	 * the target sees, so we just handshake.
1758 	 */
1759 
1760 	rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, SR_REQ, 60 * HZ);
1761 
1762 	if(rc < 0)
1763 		return -1;
1764 
1765 	tmp = (unsigned char)rc;
1766 
1767 	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1768 
1769 	if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1770 		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1771 		rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, 0, 3*HZ);
1772 		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1773 		if(rc == -1)
1774 			return -1;
1775 	}
1776 	tmp = ABORT;
1777 	msgptr = &tmp;
1778 	len = 1;
1779 	phase = PHASE_MSGOUT;
1780 	NCR5380_transfer_pio(host, &phase, &len, &msgptr);
1781 
1782 	/*
1783 	 * If we got here, and the command completed successfully,
1784 	 * we're about to go into bus free state.
1785 	 */
1786 
1787 	return len ? -1 : 0;
1788 }
1789 
1790 #if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL)
1791 /*
1792  * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1793  *      unsigned char *phase, int *count, unsigned char **data)
1794  *
1795  * Purpose : transfers data in given phase using either real
1796  *      or pseudo DMA.
1797  *
1798  * Inputs : instance - instance of driver, *phase - pointer to
1799  *      what phase is expected, *count - pointer to number of
1800  *      bytes to transfer, **data - pointer to data pointer.
1801  *
1802  * Returns : -1 when different phase is entered without transferring
1803  *      maximum number of bytes, 0 if all bytes or transferred or exit
1804  *      is in same phase.
1805  *
1806  *      Also, *phase, *count, *data are modified in place.
1807  *
1808  *	Locks: io_request lock held by caller
1809  */
1810 
1811 
1812 static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1813 	NCR5380_local_declare();
1814 	register int c = *count;
1815 	register unsigned char p = *phase;
1816 	register unsigned char *d = *data;
1817 	unsigned char tmp;
1818 	int foo;
1819 #if defined(REAL_DMA_POLL)
1820 	int cnt, toPIO;
1821 	unsigned char saved_data = 0, overrun = 0, residue;
1822 #endif
1823 
1824 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1825 
1826 	NCR5380_setup(instance);
1827 
1828 	if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1829 		*phase = tmp;
1830 		return -1;
1831 	}
1832 #if defined(REAL_DMA) || defined(REAL_DMA_POLL)
1833 #ifdef READ_OVERRUNS
1834 	if (p & SR_IO) {
1835 		c -= 2;
1836 	}
1837 #endif
1838 	dprintk(NDEBUG_DMA, ("scsi%d : initializing DMA channel %d for %s, %d bytes %s %0x\n", instance->host_no, instance->dma_channel, (p & SR_IO) ? "reading" : "writing", c, (p & SR_IO) ? "to" : "from", (unsigned) d));
1839 	hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c);
1840 #endif
1841 
1842 	NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1843 
1844 #ifdef REAL_DMA
1845 	NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1846 #elif defined(REAL_DMA_POLL)
1847 	NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1848 #else
1849 	/*
1850 	 * Note : on my sample board, watch-dog timeouts occurred when interrupts
1851 	 * were not disabled for the duration of a single DMA transfer, from
1852 	 * before the setting of DMA mode to after transfer of the last byte.
1853 	 */
1854 
1855 #if defined(PSEUDO_DMA) && defined(UNSAFE)
1856 	spin_unlock_irq(instance->host_lock);
1857 #endif
1858 	/* KLL May need eop and parity in 53c400 */
1859 	if (hostdata->flags & FLAG_NCR53C400)
1860 		NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE |
1861 				MR_ENABLE_PAR_CHECK | MR_ENABLE_PAR_INTR |
1862 				MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1863 	else
1864 		NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1865 #endif				/* def REAL_DMA */
1866 
1867 	dprintk(NDEBUG_DMA, ("scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG)));
1868 
1869 	/*
1870 	 *	On the PAS16 at least I/O recovery delays are not needed here.
1871 	 *	Everyone else seems to want them.
1872 	 */
1873 
1874 	if (p & SR_IO) {
1875 		io_recovery_delay(1);
1876 		NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1877 	} else {
1878 		io_recovery_delay(1);
1879 		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1880 		io_recovery_delay(1);
1881 		NCR5380_write(START_DMA_SEND_REG, 0);
1882 		io_recovery_delay(1);
1883 	}
1884 
1885 #if defined(REAL_DMA_POLL)
1886 	do {
1887 		tmp = NCR5380_read(BUS_AND_STATUS_REG);
1888 	} while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER)));
1889 
1890 /*
1891    At this point, either we've completed DMA, or we have a phase mismatch,
1892    or we've unexpectedly lost BUSY (which is a real error).
1893 
1894    For write DMAs, we want to wait until the last byte has been
1895    transferred out over the bus before we turn off DMA mode.  Alas, there
1896    seems to be no terribly good way of doing this on a 5380 under all
1897    conditions.  For non-scatter-gather operations, we can wait until REQ
1898    and ACK both go false, or until a phase mismatch occurs.  Gather-writes
1899    are nastier, since the device will be expecting more data than we
1900    are prepared to send it, and REQ will remain asserted.  On a 53C8[01] we
1901    could test LAST BIT SENT to assure transfer (I imagine this is precisely
1902    why this signal was added to the newer chips) but on the older 538[01]
1903    this signal does not exist.  The workaround for this lack is a watchdog;
1904    we bail out of the wait-loop after a modest amount of wait-time if
1905    the usual exit conditions are not met.  Not a terribly clean or
1906    correct solution :-%
1907 
1908    Reads are equally tricky due to a nasty characteristic of the NCR5380.
1909    If the chip is in DMA mode for an READ, it will respond to a target's
1910    REQ by latching the SCSI data into the INPUT DATA register and asserting
1911    ACK, even if it has _already_ been notified by the DMA controller that
1912    the current DMA transfer has completed!  If the NCR5380 is then taken
1913    out of DMA mode, this already-acknowledged byte is lost.
1914 
1915    This is not a problem for "one DMA transfer per command" reads, because
1916    the situation will never arise... either all of the data is DMA'ed
1917    properly, or the target switches to MESSAGE IN phase to signal a
1918    disconnection (either operation bringing the DMA to a clean halt).
1919    However, in order to handle scatter-reads, we must work around the
1920    problem.  The chosen fix is to DMA N-2 bytes, then check for the
1921    condition before taking the NCR5380 out of DMA mode.  One or two extra
1922    bytes are transferred via PIO as necessary to fill out the original
1923    request.
1924  */
1925 
1926 	if (p & SR_IO) {
1927 #ifdef READ_OVERRUNS
1928 		udelay(10);
1929 		if (((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == (BASR_PHASE_MATCH | BASR_ACK))) {
1930 			saved_data = NCR5380_read(INPUT_DATA_REGISTER);
1931 			overrun = 1;
1932 		}
1933 #endif
1934 	} else {
1935 		int limit = 100;
1936 		while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) {
1937 			if (!(tmp & BASR_PHASE_MATCH))
1938 				break;
1939 			if (--limit < 0)
1940 				break;
1941 		}
1942 	}
1943 
1944 	dprintk(NDEBUG_DMA, ("scsi%d : polled DMA transfer complete, basr 0x%X, sr 0x%X\n", instance->host_no, tmp, NCR5380_read(STATUS_REG)));
1945 
1946 	NCR5380_write(MODE_REG, MR_BASE);
1947 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1948 
1949 	residue = NCR5380_dma_residual(instance);
1950 	c -= residue;
1951 	*count -= c;
1952 	*data += c;
1953 	*phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
1954 
1955 #ifdef READ_OVERRUNS
1956 	if (*phase == p && (p & SR_IO) && residue == 0) {
1957 		if (overrun) {
1958 			dprintk(NDEBUG_DMA, ("Got an input overrun, using saved byte\n"));
1959 			**data = saved_data;
1960 			*data += 1;
1961 			*count -= 1;
1962 			cnt = toPIO = 1;
1963 		} else {
1964 			printk("No overrun??\n");
1965 			cnt = toPIO = 2;
1966 		}
1967 		dprintk(NDEBUG_DMA, ("Doing %d-byte PIO to 0x%X\n", cnt, *data));
1968 		NCR5380_transfer_pio(instance, phase, &cnt, data);
1969 		*count -= toPIO - cnt;
1970 	}
1971 #endif
1972 
1973 	dprintk(NDEBUG_DMA, ("Return with data ptr = 0x%X, count %d, last 0x%X, next 0x%X\n", *data, *count, *(*data + *count - 1), *(*data + *count)));
1974 	return 0;
1975 
1976 #elif defined(REAL_DMA)
1977 	return 0;
1978 #else				/* defined(REAL_DMA_POLL) */
1979 	if (p & SR_IO) {
1980 #ifdef DMA_WORKS_RIGHT
1981 		foo = NCR5380_pread(instance, d, c);
1982 #else
1983 		int diff = 1;
1984 		if (hostdata->flags & FLAG_NCR53C400) {
1985 			diff = 0;
1986 		}
1987 		if (!(foo = NCR5380_pread(instance, d, c - diff))) {
1988 			/*
1989 			 * We can't disable DMA mode after successfully transferring
1990 			 * what we plan to be the last byte, since that would open up
1991 			 * a race condition where if the target asserted REQ before
1992 			 * we got the DMA mode reset, the NCR5380 would have latched
1993 			 * an additional byte into the INPUT DATA register and we'd
1994 			 * have dropped it.
1995 			 *
1996 			 * The workaround was to transfer one fewer bytes than we
1997 			 * intended to with the pseudo-DMA read function, wait for
1998 			 * the chip to latch the last byte, read it, and then disable
1999 			 * pseudo-DMA mode.
2000 			 *
2001 			 * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
2002 			 * REQ is deasserted when ACK is asserted, and not reasserted
2003 			 * until ACK goes false.  Since the NCR5380 won't lower ACK
2004 			 * until DACK is asserted, which won't happen unless we twiddle
2005 			 * the DMA port or we take the NCR5380 out of DMA mode, we
2006 			 * can guarantee that we won't handshake another extra
2007 			 * byte.
2008 			 */
2009 
2010 			if (!(hostdata->flags & FLAG_NCR53C400)) {
2011 				while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ));
2012 				/* Wait for clean handshake */
2013 				while (NCR5380_read(STATUS_REG) & SR_REQ);
2014 				d[c - 1] = NCR5380_read(INPUT_DATA_REG);
2015 			}
2016 		}
2017 #endif
2018 	} else {
2019 #ifdef DMA_WORKS_RIGHT
2020 		foo = NCR5380_pwrite(instance, d, c);
2021 #else
2022 		int timeout;
2023 		dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c));
2024 		if (!(foo = NCR5380_pwrite(instance, d, c))) {
2025 			/*
2026 			 * Wait for the last byte to be sent.  If REQ is being asserted for
2027 			 * the byte we're interested, we'll ACK it and it will go false.
2028 			 */
2029 			if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) {
2030 				timeout = 20000;
2031 				while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH));
2032 
2033 				if (!timeout)
2034 					dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no));
2035 
2036 				if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) {
2037 					hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT;
2038 					if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) {
2039 						hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT;
2040 						dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no));
2041 					}
2042 				}
2043 			} else {
2044 				dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n"));
2045 				while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT));
2046 				dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n"));
2047 			}
2048 		}
2049 #endif
2050 	}
2051 	NCR5380_write(MODE_REG, MR_BASE);
2052 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2053 
2054 	if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) {
2055 		dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n"));
2056 		if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) {
2057 			dprintk(NDEBUG_C400_PWRITE, ("53C400w:    got it, reading reset interrupt reg\n"));
2058 			NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2059 		} else {
2060 			printk("53C400w:    IRQ NOT THERE!\n");
2061 		}
2062 	}
2063 	*data = d + c;
2064 	*count = 0;
2065 	*phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
2066 #if defined(PSEUDO_DMA) && defined(UNSAFE)
2067 	spin_lock_irq(instance->host_lock);
2068 #endif				/* defined(REAL_DMA_POLL) */
2069 	return foo;
2070 #endif				/* def REAL_DMA */
2071 }
2072 #endif				/* defined(REAL_DMA) | defined(PSEUDO_DMA) */
2073 
2074 /*
2075  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
2076  *
2077  * Purpose : run through the various SCSI phases and do as the target
2078  *      directs us to.  Operates on the currently connected command,
2079  *      instance->connected.
2080  *
2081  * Inputs : instance, instance for which we are doing commands
2082  *
2083  * Side effects : SCSI things happen, the disconnected queue will be
2084  *      modified if a command disconnects, *instance->connected will
2085  *      change.
2086  *
2087  * XXX Note : we need to watch for bus free or a reset condition here
2088  *      to recover from an unexpected bus free condition.
2089  *
2090  * Locks: io_request_lock held by caller in IRQ mode
2091  */
2092 
2093 static void NCR5380_information_transfer(struct Scsi_Host *instance) {
2094 	NCR5380_local_declare();
2095 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata;
2096 	unsigned char msgout = NOP;
2097 	int sink = 0;
2098 	int len;
2099 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2100 	int transfersize;
2101 #endif
2102 	unsigned char *data;
2103 	unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2104 	Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2105 	/* RvC: we need to set the end of the polling time */
2106 	unsigned long poll_time = jiffies + USLEEP_POLL;
2107 
2108 	NCR5380_setup(instance);
2109 
2110 	while (1) {
2111 		tmp = NCR5380_read(STATUS_REG);
2112 		/* We only have a valid SCSI phase when REQ is asserted */
2113 		if (tmp & SR_REQ) {
2114 			phase = (tmp & PHASE_MASK);
2115 			if (phase != old_phase) {
2116 				old_phase = phase;
2117 				NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
2118 			}
2119 			if (sink && (phase != PHASE_MSGOUT)) {
2120 				NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2121 
2122 				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
2123 				while (NCR5380_read(STATUS_REG) & SR_REQ);
2124 				NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2125 				sink = 0;
2126 				continue;
2127 			}
2128 			switch (phase) {
2129 			case PHASE_DATAIN:
2130 			case PHASE_DATAOUT:
2131 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2132 				printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no);
2133 				sink = 1;
2134 				do_abort(instance);
2135 				cmd->result = DID_ERROR << 16;
2136 				cmd->scsi_done(cmd);
2137 				return;
2138 #endif
2139 				/*
2140 				 * If there is no room left in the current buffer in the
2141 				 * scatter-gather list, move onto the next one.
2142 				 */
2143 
2144 				if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2145 					++cmd->SCp.buffer;
2146 					--cmd->SCp.buffers_residual;
2147 					cmd->SCp.this_residual = cmd->SCp.buffer->length;
2148 					cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2149 					dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual));
2150 				}
2151 				/*
2152 				 * The preferred transfer method is going to be
2153 				 * PSEUDO-DMA for systems that are strictly PIO,
2154 				 * since we can let the hardware do the handshaking.
2155 				 *
2156 				 * For this to work, we need to know the transfersize
2157 				 * ahead of time, since the pseudo-DMA code will sit
2158 				 * in an unconditional loop.
2159 				 */
2160 
2161 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2162 				/* KLL
2163 				 * PSEUDO_DMA is defined here. If this is the g_NCR5380
2164 				 * driver then it will always be defined, so the
2165 				 * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base
2166 				 * NCR5380 case.  I think this is a fairly clean solution.
2167 				 * We supplement these 2 if's with the flag.
2168 				 */
2169 #ifdef NCR5380_dma_xfer_len
2170 				if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) {
2171 #else
2172 				transfersize = cmd->transfersize;
2173 
2174 #ifdef LIMIT_TRANSFERSIZE	/* If we have problems with interrupt service */
2175 				if (transfersize > 512)
2176 					transfersize = 512;
2177 #endif				/* LIMIT_TRANSFERSIZE */
2178 
2179 				if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) {
2180 					/* Limit transfers to 32K, for xx400 & xx406
2181 					 * pseudoDMA that transfers in 128 bytes blocks. */
2182 					if (transfersize > 32 * 1024)
2183 						transfersize = 32 * 1024;
2184 #endif
2185 					len = transfersize;
2186 					if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) {
2187 						/*
2188 						 * If the watchdog timer fires, all future accesses to this
2189 						 * device will use the polled-IO.
2190 						 */
2191 						scmd_printk(KERN_INFO, cmd,
2192 							    "switching to slow handshake\n");
2193 						cmd->device->borken = 1;
2194 						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2195 						sink = 1;
2196 						do_abort(instance);
2197 						cmd->result = DID_ERROR << 16;
2198 						cmd->scsi_done(cmd);
2199 						/* XXX - need to source or sink data here, as appropriate */
2200 					} else
2201 						cmd->SCp.this_residual -= transfersize - len;
2202 				} else
2203 #endif				/* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */
2204 					NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **)
2205 							     &cmd->SCp.ptr);
2206 				break;
2207 			case PHASE_MSGIN:
2208 				len = 1;
2209 				data = &tmp;
2210 				NCR5380_transfer_pio(instance, &phase, &len, &data);
2211 				cmd->SCp.Message = tmp;
2212 
2213 				switch (tmp) {
2214 					/*
2215 					 * Linking lets us reduce the time required to get the
2216 					 * next command out to the device, hopefully this will
2217 					 * mean we don't waste another revolution due to the delays
2218 					 * required by ARBITRATION and another SELECTION.
2219 					 *
2220 					 * In the current implementation proposal, low level drivers
2221 					 * merely have to start the next command, pointed to by
2222 					 * next_link, done() is called as with unlinked commands.
2223 					 */
2224 #ifdef LINKED
2225 				case LINKED_CMD_COMPLETE:
2226 				case LINKED_FLG_CMD_COMPLETE:
2227 					/* Accept message by clearing ACK */
2228 					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2229 					dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun));
2230 					/*
2231 					 * Sanity check : A linked command should only terminate with
2232 					 * one of these messages if there are more linked commands
2233 					 * available.
2234 					 */
2235 					if (!cmd->next_link) {
2236 						printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun);
2237 						sink = 1;
2238 						do_abort(instance);
2239 						return;
2240 					}
2241 					initialize_SCp(cmd->next_link);
2242 					/* The next command is still part of this process */
2243 					cmd->next_link->tag = cmd->tag;
2244 					cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2245 					dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked request done, calling scsi_done().\n", instance->host_no, cmd->device->id, cmd->device->lun));
2246 					collect_stats(hostdata, cmd);
2247 					cmd->scsi_done(cmd);
2248 					cmd = hostdata->connected;
2249 					break;
2250 #endif				/* def LINKED */
2251 				case ABORT:
2252 				case COMMAND_COMPLETE:
2253 					/* Accept message by clearing ACK */
2254 					sink = 1;
2255 					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2256 					hostdata->connected = NULL;
2257 					dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun));
2258 					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2259 
2260 					/*
2261 					 * I'm not sure what the correct thing to do here is :
2262 					 *
2263 					 * If the command that just executed is NOT a request
2264 					 * sense, the obvious thing to do is to set the result
2265 					 * code to the values of the stored parameters.
2266 					 *
2267 					 * If it was a REQUEST SENSE command, we need some way
2268 					 * to differentiate between the failure code of the original
2269 					 * and the failure code of the REQUEST sense - the obvious
2270 					 * case is success, where we fall through and leave the result
2271 					 * code unchanged.
2272 					 *
2273 					 * The non-obvious place is where the REQUEST SENSE failed
2274 					 */
2275 
2276 					if (cmd->cmnd[0] != REQUEST_SENSE)
2277 						cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2278 					else if (status_byte(cmd->SCp.Status) != GOOD)
2279 						cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2280 
2281 #ifdef AUTOSENSE
2282 					if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2283 						hostdata->ses.cmd_len) {
2284 						scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2285 						hostdata->ses.cmd_len = 0 ;
2286 					}
2287 
2288 					if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2289 						scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2290 
2291 						dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no));
2292 
2293 						LIST(cmd, hostdata->issue_queue);
2294 						cmd->host_scribble = (unsigned char *)
2295 						    hostdata->issue_queue;
2296 						hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2297 						dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no));
2298 					} else
2299 #endif				/* def AUTOSENSE */
2300 					{
2301 						collect_stats(hostdata, cmd);
2302 						cmd->scsi_done(cmd);
2303 					}
2304 
2305 					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2306 					/*
2307 					 * Restore phase bits to 0 so an interrupted selection,
2308 					 * arbitration can resume.
2309 					 */
2310 					NCR5380_write(TARGET_COMMAND_REG, 0);
2311 
2312 					while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2313 						barrier();
2314 					return;
2315 				case MESSAGE_REJECT:
2316 					/* Accept message by clearing ACK */
2317 					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2318 					switch (hostdata->last_message) {
2319 					case HEAD_OF_QUEUE_TAG:
2320 					case ORDERED_QUEUE_TAG:
2321 					case SIMPLE_QUEUE_TAG:
2322 						cmd->device->simple_tags = 0;
2323 						hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2324 						break;
2325 					default:
2326 						break;
2327 					}
2328 				case DISCONNECT:{
2329 						/* Accept message by clearing ACK */
2330 						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2331 						cmd->device->disconnect = 1;
2332 						LIST(cmd, hostdata->disconnected_queue);
2333 						cmd->host_scribble = (unsigned char *)
2334 						    hostdata->disconnected_queue;
2335 						hostdata->connected = NULL;
2336 						hostdata->disconnected_queue = cmd;
2337 						dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d lun %d was moved from connected to" "  the disconnected_queue\n", instance->host_no, cmd->device->id, cmd->device->lun));
2338 						/*
2339 						 * Restore phase bits to 0 so an interrupted selection,
2340 						 * arbitration can resume.
2341 						 */
2342 						NCR5380_write(TARGET_COMMAND_REG, 0);
2343 
2344 						/* Enable reselect interrupts */
2345 						NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2346 						/* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/
2347 						/* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */
2348 						while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2349 							barrier();
2350 						return;
2351 					}
2352 					/*
2353 					 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2354 					 * operation, in violation of the SCSI spec so we can safely
2355 					 * ignore SAVE/RESTORE pointers calls.
2356 					 *
2357 					 * Unfortunately, some disks violate the SCSI spec and
2358 					 * don't issue the required SAVE_POINTERS message before
2359 					 * disconnecting, and we have to break spec to remain
2360 					 * compatible.
2361 					 */
2362 				case SAVE_POINTERS:
2363 				case RESTORE_POINTERS:
2364 					/* Accept message by clearing ACK */
2365 					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2366 					break;
2367 				case EXTENDED_MESSAGE:
2368 /*
2369  * Extended messages are sent in the following format :
2370  * Byte
2371  * 0            EXTENDED_MESSAGE == 1
2372  * 1            length (includes one byte for code, doesn't
2373  *              include first two bytes)
2374  * 2            code
2375  * 3..length+1  arguments
2376  *
2377  * Start the extended message buffer with the EXTENDED_MESSAGE
2378  * byte, since spi_print_msg() wants the whole thing.
2379  */
2380 					extended_msg[0] = EXTENDED_MESSAGE;
2381 					/* Accept first byte by clearing ACK */
2382 					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2383 					dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no));
2384 
2385 					len = 2;
2386 					data = extended_msg + 1;
2387 					phase = PHASE_MSGIN;
2388 					NCR5380_transfer_pio(instance, &phase, &len, &data);
2389 
2390 					dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2]));
2391 
2392 					if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) {
2393 						/* Accept third byte by clearing ACK */
2394 						NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2395 						len = extended_msg[1] - 1;
2396 						data = extended_msg + 3;
2397 						phase = PHASE_MSGIN;
2398 
2399 						NCR5380_transfer_pio(instance, &phase, &len, &data);
2400 						dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len));
2401 
2402 						switch (extended_msg[2]) {
2403 						case EXTENDED_SDTR:
2404 						case EXTENDED_WDTR:
2405 						case EXTENDED_MODIFY_DATA_POINTER:
2406 						case EXTENDED_EXTENDED_IDENTIFY:
2407 							tmp = 0;
2408 						}
2409 					} else if (len) {
2410 						printk("scsi%d: error receiving extended message\n", instance->host_no);
2411 						tmp = 0;
2412 					} else {
2413 						printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]);
2414 						tmp = 0;
2415 					}
2416 					/* Fall through to reject message */
2417 
2418 					/*
2419 					 * If we get something weird that we aren't expecting,
2420 					 * reject it.
2421 					 */
2422 				default:
2423 					if (!tmp) {
2424 						printk("scsi%d: rejecting message ", instance->host_no);
2425 						spi_print_msg(extended_msg);
2426 						printk("\n");
2427 					} else if (tmp != EXTENDED_MESSAGE)
2428 						scmd_printk(KERN_INFO, cmd,
2429 							"rejecting unknown message %02x\n",tmp);
2430 					else
2431 						scmd_printk(KERN_INFO, cmd,
2432 							"rejecting unknown extended message code %02x, length %d\n", extended_msg[1], extended_msg[0]);
2433 
2434 					msgout = MESSAGE_REJECT;
2435 					NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2436 					break;
2437 				}	/* switch (tmp) */
2438 				break;
2439 			case PHASE_MSGOUT:
2440 				len = 1;
2441 				data = &msgout;
2442 				hostdata->last_message = msgout;
2443 				NCR5380_transfer_pio(instance, &phase, &len, &data);
2444 				if (msgout == ABORT) {
2445 					hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2446 					hostdata->connected = NULL;
2447 					cmd->result = DID_ERROR << 16;
2448 					collect_stats(hostdata, cmd);
2449 					cmd->scsi_done(cmd);
2450 					NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2451 					return;
2452 				}
2453 				msgout = NOP;
2454 				break;
2455 			case PHASE_CMDOUT:
2456 				len = cmd->cmd_len;
2457 				data = cmd->cmnd;
2458 				/*
2459 				 * XXX for performance reasons, on machines with a
2460 				 * PSEUDO-DMA architecture we should probably
2461 				 * use the dma transfer function.
2462 				 */
2463 				NCR5380_transfer_pio(instance, &phase, &len, &data);
2464 				if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) {
2465 					NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2466 					dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2467 					return;
2468 				}
2469 				break;
2470 			case PHASE_STATIN:
2471 				len = 1;
2472 				data = &tmp;
2473 				NCR5380_transfer_pio(instance, &phase, &len, &data);
2474 				cmd->SCp.Status = tmp;
2475 				break;
2476 			default:
2477 				printk("scsi%d : unknown phase\n", instance->host_no);
2478 				NCR5380_dprint(NDEBUG_ALL, instance);
2479 			}	/* switch(phase) */
2480 		}		/* if (tmp * SR_REQ) */
2481 		else {
2482 			/* RvC: go to sleep if polling time expired
2483 			 */
2484 			if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) {
2485 				NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2486 				dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2487 				return;
2488 			}
2489 		}
2490 	}			/* while (1) */
2491 }
2492 
2493 /*
2494  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2495  *
2496  * Purpose : does reselection, initializing the instance->connected
2497  *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2498  *      nexus has been reestablished,
2499  *
2500  * Inputs : instance - this instance of the NCR5380.
2501  *
2502  * Locks: io_request_lock held by caller if IRQ driven
2503  */
2504 
2505 static void NCR5380_reselect(struct Scsi_Host *instance) {
2506 	NCR5380_local_declare();
2507 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)
2508 	 instance->hostdata;
2509 	unsigned char target_mask;
2510 	unsigned char lun, phase;
2511 	int len;
2512 	unsigned char msg[3];
2513 	unsigned char *data;
2514 	Scsi_Cmnd *tmp = NULL, *prev;
2515 	int abort = 0;
2516 	NCR5380_setup(instance);
2517 
2518 	/*
2519 	 * Disable arbitration, etc. since the host adapter obviously
2520 	 * lost, and tell an interrupted NCR5380_select() to restart.
2521 	 */
2522 
2523 	NCR5380_write(MODE_REG, MR_BASE);
2524 	hostdata->restart_select = 1;
2525 
2526 	target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2527 	dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no));
2528 
2529 	/*
2530 	 * At this point, we have detected that our SCSI ID is on the bus,
2531 	 * SEL is true and BSY was false for at least one bus settle delay
2532 	 * (400 ns).
2533 	 *
2534 	 * We must assert BSY ourselves, until the target drops the SEL
2535 	 * signal.
2536 	 */
2537 
2538 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2539 
2540 	/* FIXME: timeout too long, must fail to workqueue */
2541 	if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0)
2542 		abort = 1;
2543 
2544 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2545 
2546 	/*
2547 	 * Wait for target to go into MSGIN.
2548 	 * FIXME: timeout needed and fail to work queeu
2549 	 */
2550 
2551 	if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ))
2552 		abort = 1;
2553 
2554 	len = 1;
2555 	data = msg;
2556 	phase = PHASE_MSGIN;
2557 	NCR5380_transfer_pio(instance, &phase, &len, &data);
2558 
2559 	if (!(msg[0] & 0x80)) {
2560 		printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no);
2561 		spi_print_msg(msg);
2562 		abort = 1;
2563 	} else {
2564 		/* Accept message by clearing ACK */
2565 		NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2566 		lun = (msg[0] & 0x07);
2567 
2568 		/*
2569 		 * We need to add code for SCSI-II to track which devices have
2570 		 * I_T_L_Q nexuses established, and which have simple I_T_L
2571 		 * nexuses so we can chose to do additional data transfer.
2572 		 */
2573 
2574 		/*
2575 		 * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we
2576 		 * just reestablished, and remove it from the disconnected queue.
2577 		 */
2578 
2579 
2580 		for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
2581 			if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2582 			    ) {
2583 				if (prev) {
2584 					REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
2585 					prev->host_scribble = tmp->host_scribble;
2586 				} else {
2587 					REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble);
2588 					hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble;
2589 				}
2590 				tmp->host_scribble = NULL;
2591 				break;
2592 			}
2593 		if (!tmp) {
2594 			printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun);
2595 			/*
2596 			 * Since we have an established nexus that we can't do anything with,
2597 			 * we must abort it.
2598 			 */
2599 			abort = 1;
2600 		}
2601 	}
2602 
2603 	if (abort) {
2604 		do_abort(instance);
2605 	} else {
2606 		hostdata->connected = tmp;
2607 		dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag));
2608 	}
2609 }
2610 
2611 /*
2612  * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
2613  *
2614  * Purpose : called by interrupt handler when DMA finishes or a phase
2615  *      mismatch occurs (which would finish the DMA transfer).
2616  *
2617  * Inputs : instance - this instance of the NCR5380.
2618  *
2619  * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L
2620  *      nexus has been reestablished, on failure NULL is returned.
2621  */
2622 
2623 #ifdef REAL_DMA
2624 static void NCR5380_dma_complete(NCR5380_instance * instance) {
2625 	NCR5380_local_declare();
2626 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2627 	int transferred;
2628 	NCR5380_setup(instance);
2629 
2630 	/*
2631 	 * XXX this might not be right.
2632 	 *
2633 	 * Wait for final byte to transfer, ie wait for ACK to go false.
2634 	 *
2635 	 * We should use the Last Byte Sent bit, unfortunately this is
2636 	 * not available on the 5380/5381 (only the various CMOS chips)
2637 	 *
2638 	 * FIXME: timeout, and need to handle long timeout/irq case
2639 	 */
2640 
2641 	NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ);
2642 
2643 	NCR5380_write(MODE_REG, MR_BASE);
2644 	NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2645 
2646 	/*
2647 	 * The only places we should see a phase mismatch and have to send
2648 	 * data from the same set of pointers will be the data transfer
2649 	 * phases.  So, residual, requested length are only important here.
2650 	 */
2651 
2652 	if (!(hostdata->connected->SCp.phase & SR_CD)) {
2653 		transferred = instance->dmalen - NCR5380_dma_residual();
2654 		hostdata->connected->SCp.this_residual -= transferred;
2655 		hostdata->connected->SCp.ptr += transferred;
2656 	}
2657 }
2658 #endif				/* def REAL_DMA */
2659 
2660 /*
2661  * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2662  *
2663  * Purpose : abort a command
2664  *
2665  * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2666  *      host byte of the result field to, if zero DID_ABORTED is
2667  *      used.
2668  *
2669  * Returns : 0 - success, -1 on failure.
2670  *
2671  *	XXX - there is no way to abort the command that is currently
2672  *	connected, you have to wait for it to complete.  If this is
2673  *	a problem, we could implement longjmp() / setjmp(), setjmp()
2674  *	called where the loop started in NCR5380_main().
2675  *
2676  * Locks: host lock taken by caller
2677  */
2678 
2679 static int NCR5380_abort(Scsi_Cmnd * cmd) {
2680 	NCR5380_local_declare();
2681 	struct Scsi_Host *instance = cmd->device->host;
2682 	struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2683 	Scsi_Cmnd *tmp, **prev;
2684 
2685 	printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no);
2686 	scsi_print_command(cmd);
2687 
2688 	NCR5380_print_status(instance);
2689 
2690 	NCR5380_setup(instance);
2691 
2692 	dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no));
2693 	dprintk(NDEBUG_ABORT, ("        basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)));
2694 
2695 #if 0
2696 /*
2697  * Case 1 : If the command is the currently executing command,
2698  * we'll set the aborted flag and return control so that
2699  * information transfer routine can exit cleanly.
2700  */
2701 
2702 	if (hostdata->connected == cmd) {
2703 		dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no));
2704 		hostdata->aborted = 1;
2705 /*
2706  * We should perform BSY checking, and make sure we haven't slipped
2707  * into BUS FREE.
2708  */
2709 
2710 		NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN);
2711 /*
2712  * Since we can't change phases until we've completed the current
2713  * handshake, we have to source or sink a byte of data if the current
2714  * phase is not MSGOUT.
2715  */
2716 
2717 /*
2718  * Return control to the executing NCR drive so we can clear the
2719  * aborted flag and get back into our main loop.
2720  */
2721 
2722 		return 0;
2723 	}
2724 #endif
2725 
2726 /*
2727  * Case 2 : If the command hasn't been issued yet, we simply remove it
2728  *          from the issue queue.
2729  */
2730 
2731 	dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no));
2732 	for (prev = (Scsi_Cmnd **) & (hostdata->issue_queue), tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
2733 		if (cmd == tmp) {
2734 			REMOVE(5, *prev, tmp, tmp->host_scribble);
2735 			(*prev) = (Scsi_Cmnd *) tmp->host_scribble;
2736 			tmp->host_scribble = NULL;
2737 			tmp->result = DID_ABORT << 16;
2738 			dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no));
2739 			tmp->scsi_done(tmp);
2740 			return SUCCESS;
2741 		}
2742 #if (NDEBUG  & NDEBUG_ABORT)
2743 	/* KLL */
2744 		else if (prev == tmp)
2745 			printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no);
2746 #endif
2747 
2748 /*
2749  * Case 3 : If any commands are connected, we're going to fail the abort
2750  *          and let the high level SCSI driver retry at a later time or
2751  *          issue a reset.
2752  *
2753  *          Timeouts, and therefore aborted commands, will be highly unlikely
2754  *          and handling them cleanly in this situation would make the common
2755  *          case of noresets less efficient, and would pollute our code.  So,
2756  *          we fail.
2757  */
2758 
2759 	if (hostdata->connected) {
2760 		dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no));
2761 		return FAILED;
2762 	}
2763 /*
2764  * Case 4: If the command is currently disconnected from the bus, and
2765  *      there are no connected commands, we reconnect the I_T_L or
2766  *      I_T_L_Q nexus associated with it, go into message out, and send
2767  *      an abort message.
2768  *
2769  * This case is especially ugly. In order to reestablish the nexus, we
2770  * need to call NCR5380_select().  The easiest way to implement this
2771  * function was to abort if the bus was busy, and let the interrupt
2772  * handler triggered on the SEL for reselect take care of lost arbitrations
2773  * where necessary, meaning interrupts need to be enabled.
2774  *
2775  * When interrupts are enabled, the queues may change - so we
2776  * can't remove it from the disconnected queue before selecting it
2777  * because that could cause a failure in hashing the nexus if that
2778  * device reselected.
2779  *
2780  * Since the queues may change, we can't use the pointers from when we
2781  * first locate it.
2782  *
2783  * So, we must first locate the command, and if NCR5380_select()
2784  * succeeds, then issue the abort, relocate the command and remove
2785  * it from the disconnected queue.
2786  */
2787 
2788 	for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble)
2789 		if (cmd == tmp) {
2790 			dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no));
2791 
2792 			if (NCR5380_select(instance, cmd, (int) cmd->tag))
2793 				return FAILED;
2794 			dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no));
2795 
2796 			do_abort(instance);
2797 
2798 			for (prev = (Scsi_Cmnd **) & (hostdata->disconnected_queue), tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
2799 				if (cmd == tmp) {
2800 					REMOVE(5, *prev, tmp, tmp->host_scribble);
2801 					*prev = (Scsi_Cmnd *) tmp->host_scribble;
2802 					tmp->host_scribble = NULL;
2803 					tmp->result = DID_ABORT << 16;
2804 					tmp->scsi_done(tmp);
2805 					return SUCCESS;
2806 				}
2807 		}
2808 /*
2809  * Case 5 : If we reached this point, the command was not found in any of
2810  *          the queues.
2811  *
2812  * We probably reached this point because of an unlikely race condition
2813  * between the command completing successfully and the abortion code,
2814  * so we won't panic, but we will notify the user in case something really
2815  * broke.
2816  */
2817 	printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n"
2818 			"         before abortion\n", instance->host_no);
2819 	return FAILED;
2820 }
2821 
2822 
2823 /*
2824  * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd)
2825  *
2826  * Purpose : reset the SCSI bus.
2827  *
2828  * Returns : SUCCESS
2829  *
2830  * Locks: host lock taken by caller
2831  */
2832 
2833 static int NCR5380_bus_reset(Scsi_Cmnd * cmd)
2834 {
2835 	struct Scsi_Host *instance = cmd->device->host;
2836 
2837 	NCR5380_local_declare();
2838 	NCR5380_setup(instance);
2839 	NCR5380_print_status(instance);
2840 
2841 	spin_lock_irq(instance->host_lock);
2842 	do_reset(instance);
2843 	spin_unlock_irq(instance->host_lock);
2844 
2845 	return SUCCESS;
2846 }
2847