Loading...
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
281static int do_abort(struct Scsi_Host *host);
282static 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
291static __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
325static 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
356static 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
370static 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},
384basrs[] = {
385 {BASR_ATN, "ATN"},
386 {BASR_ACK, "ACK"},
387 {0, NULL}
388},
389icrs[] = {
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},
398mrs[] = {
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
418static 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
459static 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
521static 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
541static 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
548static 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
560static 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
577static 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, 0, "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
632static void __init __maybe_unused
633NCR5380_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
678static 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
698static int __maybe_unused NCR5380_write_info(struct Scsi_Host *instance,
699 char *buffer, int length)
700{
701#ifdef DTC_PUBLIC_RELEASE
702 dtc_wmaxi = dtc_maxi = 0;
703#endif
704#ifdef PAS16_PUBLIC_RELEASE
705 pas_wmaxi = pas_maxi = 0;
706#endif
707 return (-ENOSYS); /* Currently this is a no-op */
708}
709
710#undef SPRINTF
711#define SPRINTF(args...) seq_printf(m, ## args)
712static
713void lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, struct seq_file *m);
714static
715void lprint_command(unsigned char *cmd, struct seq_file *m);
716static
717void lprint_opcode(int opcode, struct seq_file *m);
718
719static int __maybe_unused NCR5380_show_info(struct seq_file *m,
720 struct Scsi_Host *instance)
721{
722 struct NCR5380_hostdata *hostdata;
723 Scsi_Cmnd *ptr;
724
725 hostdata = (struct NCR5380_hostdata *) instance->hostdata;
726
727 SPRINTF("NCR5380 core release=%d. ", NCR5380_PUBLIC_RELEASE);
728 if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400)
729 SPRINTF("ncr53c400 release=%d. ", NCR53C400_PUBLIC_RELEASE);
730#ifdef DTC_PUBLIC_RELEASE
731 SPRINTF("DTC 3180/3280 release %d", DTC_PUBLIC_RELEASE);
732#endif
733#ifdef T128_PUBLIC_RELEASE
734 SPRINTF("T128 release %d", T128_PUBLIC_RELEASE);
735#endif
736#ifdef GENERIC_NCR5380_PUBLIC_RELEASE
737 SPRINTF("Generic5380 release %d", GENERIC_NCR5380_PUBLIC_RELEASE);
738#endif
739#ifdef PAS16_PUBLIC_RELEASE
740 SPRINTF("PAS16 release=%d", PAS16_PUBLIC_RELEASE);
741#endif
742
743 SPRINTF("\nBase Addr: 0x%05lX ", (long) instance->base);
744 SPRINTF("io_port: %04x ", (int) instance->io_port);
745 if (instance->irq == SCSI_IRQ_NONE)
746 SPRINTF("IRQ: None.\n");
747 else
748 SPRINTF("IRQ: %d.\n", instance->irq);
749
750#ifdef DTC_PUBLIC_RELEASE
751 SPRINTF("Highwater I/O busy_spin_counts -- write: %d read: %d\n", dtc_wmaxi, dtc_maxi);
752#endif
753#ifdef PAS16_PUBLIC_RELEASE
754 SPRINTF("Highwater I/O busy_spin_counts -- write: %d read: %d\n", pas_wmaxi, pas_maxi);
755#endif
756 spin_lock_irq(instance->host_lock);
757 if (!hostdata->connected)
758 SPRINTF("scsi%d: no currently connected command\n", instance->host_no);
759 else
760 lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, m);
761 SPRINTF("scsi%d: issue_queue\n", instance->host_no);
762 for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
763 lprint_Scsi_Cmnd(ptr, m);
764
765 SPRINTF("scsi%d: disconnected_queue\n", instance->host_no);
766 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
767 lprint_Scsi_Cmnd(ptr, m);
768 spin_unlock_irq(instance->host_lock);
769 return 0;
770}
771
772static void lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, struct seq_file *m)
773{
774 SPRINTF("scsi%d : destination target %d, lun %d\n", cmd->device->host->host_no, cmd->device->id, cmd->device->lun);
775 SPRINTF(" command = ");
776 lprint_command(cmd->cmnd, m);
777}
778
779static void lprint_command(unsigned char *command, struct seq_file *m)
780{
781 int i, s;
782 lprint_opcode(command[0], m);
783 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
784 SPRINTF("%02x ", command[i]);
785 SPRINTF("\n");
786}
787
788static void lprint_opcode(int opcode, struct seq_file *m)
789{
790 SPRINTF("%2d (0x%02x)", opcode, opcode);
791}
792
793
794/**
795 * NCR5380_init - initialise an NCR5380
796 * @instance: adapter to configure
797 * @flags: control flags
798 *
799 * Initializes *instance and corresponding 5380 chip,
800 * with flags OR'd into the initial flags value.
801 *
802 * Notes : I assume that the host, hostno, and id bits have been
803 * set correctly. I don't care about the irq and other fields.
804 *
805 * Returns 0 for success
806 *
807 * Locks: interrupts must be enabled when we are called
808 */
809
810static int NCR5380_init(struct Scsi_Host *instance, int flags)
811{
812 NCR5380_local_declare();
813 int i, pass;
814 unsigned long timeout;
815 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
816
817 if(in_interrupt())
818 printk(KERN_ERR "NCR5380_init called with interrupts off!\n");
819 /*
820 * On NCR53C400 boards, NCR5380 registers are mapped 8 past
821 * the base address.
822 */
823
824#ifdef NCR53C400
825 if (flags & FLAG_NCR53C400)
826 instance->NCR5380_instance_name += NCR53C400_address_adjust;
827#endif
828
829 NCR5380_setup(instance);
830
831 hostdata->aborted = 0;
832 hostdata->id_mask = 1 << instance->this_id;
833 for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
834 if (i > hostdata->id_mask)
835 hostdata->id_higher_mask |= i;
836 for (i = 0; i < 8; ++i)
837 hostdata->busy[i] = 0;
838#ifdef REAL_DMA
839 hostdata->dmalen = 0;
840#endif
841 hostdata->targets_present = 0;
842 hostdata->connected = NULL;
843 hostdata->issue_queue = NULL;
844 hostdata->disconnected_queue = NULL;
845
846 INIT_DELAYED_WORK(&hostdata->coroutine, NCR5380_main);
847
848#ifdef NCR5380_STATS
849 for (i = 0; i < 8; ++i) {
850 hostdata->time_read[i] = 0;
851 hostdata->time_write[i] = 0;
852 hostdata->bytes_read[i] = 0;
853 hostdata->bytes_write[i] = 0;
854 }
855 hostdata->timebase = 0;
856 hostdata->pendingw = 0;
857 hostdata->pendingr = 0;
858#endif
859
860 /* The CHECK code seems to break the 53C400. Will check it later maybe */
861 if (flags & FLAG_NCR53C400)
862 hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags;
863 else
864 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags;
865
866 hostdata->host = instance;
867 hostdata->time_expires = 0;
868
869#ifndef AUTOSENSE
870 if ((instance->cmd_per_lun > 1) || instance->can_queue > 1)
871 printk(KERN_WARNING "scsi%d : WARNING : support for multiple outstanding commands enabled\n" " without AUTOSENSE option, contingent allegiance conditions may\n"
872 " be incorrectly cleared.\n", instance->host_no);
873#endif /* def AUTOSENSE */
874
875 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
876 NCR5380_write(MODE_REG, MR_BASE);
877 NCR5380_write(TARGET_COMMAND_REG, 0);
878 NCR5380_write(SELECT_ENABLE_REG, 0);
879
880#ifdef NCR53C400
881 if (hostdata->flags & FLAG_NCR53C400) {
882 NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE);
883 }
884#endif
885
886 /*
887 * Detect and correct bus wedge problems.
888 *
889 * If the system crashed, it may have crashed in a state
890 * where a SCSI command was still executing, and the
891 * SCSI bus is not in a BUS FREE STATE.
892 *
893 * If this is the case, we'll try to abort the currently
894 * established nexus which we know nothing about, and that
895 * failing, do a hard reset of the SCSI bus
896 */
897
898 for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
899 switch (pass) {
900 case 1:
901 case 3:
902 case 5:
903 printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no);
904 timeout = jiffies + 5 * HZ;
905 NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ);
906 break;
907 case 2:
908 printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no);
909 do_abort(instance);
910 break;
911 case 4:
912 printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no);
913 do_reset(instance);
914 break;
915 case 6:
916 printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no);
917 return -ENXIO;
918 }
919 }
920 return 0;
921}
922
923/**
924 * NCR5380_exit - remove an NCR5380
925 * @instance: adapter to remove
926 */
927
928static void NCR5380_exit(struct Scsi_Host *instance)
929{
930 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
931
932 cancel_delayed_work_sync(&hostdata->coroutine);
933}
934
935/**
936 * NCR5380_queue_command - queue a command
937 * @cmd: SCSI command
938 * @done: completion handler
939 *
940 * cmd is added to the per instance issue_queue, with minor
941 * twiddling done to the host specific fields of cmd. If the
942 * main coroutine is not running, it is restarted.
943 *
944 * Locks: host lock taken by caller
945 */
946
947static int NCR5380_queue_command_lck(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *))
948{
949 struct Scsi_Host *instance = cmd->device->host;
950 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
951 Scsi_Cmnd *tmp;
952
953#if (NDEBUG & NDEBUG_NO_WRITE)
954 switch (cmd->cmnd[0]) {
955 case WRITE_6:
956 case WRITE_10:
957 printk("scsi%d : WRITE attempted with NO_WRITE debugging flag set\n", instance->host_no);
958 cmd->result = (DID_ERROR << 16);
959 done(cmd);
960 return 0;
961 }
962#endif /* (NDEBUG & NDEBUG_NO_WRITE) */
963
964#ifdef NCR5380_STATS
965 switch (cmd->cmnd[0]) {
966 case WRITE:
967 case WRITE_6:
968 case WRITE_10:
969 hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
970 hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);
971 hostdata->pendingw++;
972 break;
973 case READ:
974 case READ_6:
975 case READ_10:
976 hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
977 hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);
978 hostdata->pendingr++;
979 break;
980 }
981#endif
982
983 /*
984 * We use the host_scribble field as a pointer to the next command
985 * in a queue
986 */
987
988 cmd->host_scribble = NULL;
989 cmd->scsi_done = done;
990 cmd->result = 0;
991
992 /*
993 * Insert the cmd into the issue queue. Note that REQUEST SENSE
994 * commands are added to the head of the queue since any command will
995 * clear the contingent allegiance condition that exists and the
996 * sense data is only guaranteed to be valid while the condition exists.
997 */
998
999 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
1000 LIST(cmd, hostdata->issue_queue);
1001 cmd->host_scribble = (unsigned char *) hostdata->issue_queue;
1002 hostdata->issue_queue = cmd;
1003 } else {
1004 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp->host_scribble; tmp = (Scsi_Cmnd *) tmp->host_scribble);
1005 LIST(cmd, tmp);
1006 tmp->host_scribble = (unsigned char *) cmd;
1007 }
1008 dprintk(NDEBUG_QUEUES, ("scsi%d : command added to %s of queue\n", instance->host_no, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"));
1009
1010 /* Run the coroutine if it isn't already running. */
1011 /* Kick off command processing */
1012 schedule_delayed_work(&hostdata->coroutine, 0);
1013 return 0;
1014}
1015
1016static DEF_SCSI_QCMD(NCR5380_queue_command)
1017
1018/**
1019 * NCR5380_main - NCR state machines
1020 *
1021 * NCR5380_main is a coroutine that runs as long as more work can
1022 * be done on the NCR5380 host adapters in a system. Both
1023 * NCR5380_queue_command() and NCR5380_intr() will try to start it
1024 * in case it is not running.
1025 *
1026 * Locks: called as its own thread with no locks held. Takes the
1027 * host lock and called routines may take the isa dma lock.
1028 */
1029
1030static void NCR5380_main(struct work_struct *work)
1031{
1032 struct NCR5380_hostdata *hostdata =
1033 container_of(work, struct NCR5380_hostdata, coroutine.work);
1034 struct Scsi_Host *instance = hostdata->host;
1035 Scsi_Cmnd *tmp, *prev;
1036 int done;
1037
1038 spin_lock_irq(instance->host_lock);
1039 do {
1040 /* Lock held here */
1041 done = 1;
1042 if (!hostdata->connected && !hostdata->selecting) {
1043 dprintk(NDEBUG_MAIN, ("scsi%d : not connected\n", instance->host_no));
1044 /*
1045 * Search through the issue_queue for a command destined
1046 * for a target that's not busy.
1047 */
1048 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
1049 {
1050 if (prev != tmp)
1051 dprintk(NDEBUG_LISTS, ("MAIN tmp=%p target=%d busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun));
1052 /* When we find one, remove it from the issue queue. */
1053 if (!(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))) {
1054 if (prev) {
1055 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
1056 prev->host_scribble = tmp->host_scribble;
1057 } else {
1058 REMOVE(-1, hostdata->issue_queue, tmp, tmp->host_scribble);
1059 hostdata->issue_queue = (Scsi_Cmnd *) tmp->host_scribble;
1060 }
1061 tmp->host_scribble = NULL;
1062
1063 /*
1064 * Attempt to establish an I_T_L nexus here.
1065 * On success, instance->hostdata->connected is set.
1066 * On failure, we must add the command back to the
1067 * issue queue so we can keep trying.
1068 */
1069 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));
1070
1071 /*
1072 * A successful selection is defined as one that
1073 * leaves us with the command connected and
1074 * in hostdata->connected, OR has terminated the
1075 * command.
1076 *
1077 * With successful commands, we fall through
1078 * and see if we can do an information transfer,
1079 * with failures we will restart.
1080 */
1081 hostdata->selecting = NULL;
1082 /* RvC: have to preset this to indicate a new command is being performed */
1083
1084 if (!NCR5380_select(instance, tmp,
1085 /*
1086 * REQUEST SENSE commands are issued without tagged
1087 * queueing, even on SCSI-II devices because the
1088 * contingent allegiance condition exists for the
1089 * entire unit.
1090 */
1091 (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1092 break;
1093 } else {
1094 LIST(tmp, hostdata->issue_queue);
1095 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1096 hostdata->issue_queue = tmp;
1097 done = 0;
1098 dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main(): select() failed, returned to issue_queue\n", instance->host_no));
1099 }
1100 /* lock held here still */
1101 } /* if target/lun is not busy */
1102 } /* for */
1103 /* exited locked */
1104 } /* if (!hostdata->connected) */
1105 if (hostdata->selecting) {
1106 tmp = (Scsi_Cmnd *) hostdata->selecting;
1107 /* Selection will drop and retake the lock */
1108 if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1109 /* Ok ?? */
1110 } else {
1111 /* RvC: device failed, so we wait a long time
1112 this is needed for Mustek scanners, that
1113 do not respond to commands immediately
1114 after a scan */
1115 printk(KERN_DEBUG "scsi%d: device %d did not respond in time\n", instance->host_no, tmp->device->id);
1116 LIST(tmp, hostdata->issue_queue);
1117 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1118 hostdata->issue_queue = tmp;
1119 NCR5380_set_timer(hostdata, USLEEP_WAITLONG);
1120 }
1121 } /* if hostdata->selecting */
1122 if (hostdata->connected
1123#ifdef REAL_DMA
1124 && !hostdata->dmalen
1125#endif
1126 && (!hostdata->time_expires || time_before_eq(hostdata->time_expires, jiffies))
1127 ) {
1128 dprintk(NDEBUG_MAIN, ("scsi%d : main() : performing information transfer\n", instance->host_no));
1129 NCR5380_information_transfer(instance);
1130 dprintk(NDEBUG_MAIN, ("scsi%d : main() : done set false\n", instance->host_no));
1131 done = 0;
1132 } else
1133 break;
1134 } while (!done);
1135
1136 spin_unlock_irq(instance->host_lock);
1137}
1138
1139#ifndef DONT_USE_INTR
1140
1141/**
1142 * NCR5380_intr - generic NCR5380 irq handler
1143 * @irq: interrupt number
1144 * @dev_id: device info
1145 *
1146 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1147 * from the disconnected queue, and restarting NCR5380_main()
1148 * as required.
1149 *
1150 * Locks: takes the needed instance locks
1151 */
1152
1153static irqreturn_t NCR5380_intr(int dummy, void *dev_id)
1154{
1155 NCR5380_local_declare();
1156 struct Scsi_Host *instance = dev_id;
1157 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1158 int done;
1159 unsigned char basr;
1160 unsigned long flags;
1161
1162 dprintk(NDEBUG_INTR, ("scsi : NCR5380 irq %d triggered\n",
1163 instance->irq));
1164
1165 do {
1166 done = 1;
1167 spin_lock_irqsave(instance->host_lock, flags);
1168 /* Look for pending interrupts */
1169 NCR5380_setup(instance);
1170 basr = NCR5380_read(BUS_AND_STATUS_REG);
1171 /* XXX dispatch to appropriate routine if found and done=0 */
1172 if (basr & BASR_IRQ) {
1173 NCR5380_dprint(NDEBUG_INTR, instance);
1174 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1175 done = 0;
1176 dprintk(NDEBUG_INTR, ("scsi%d : SEL interrupt\n", instance->host_no));
1177 NCR5380_reselect(instance);
1178 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1179 } else if (basr & BASR_PARITY_ERROR) {
1180 dprintk(NDEBUG_INTR, ("scsi%d : PARITY interrupt\n", instance->host_no));
1181 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1182 } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1183 dprintk(NDEBUG_INTR, ("scsi%d : RESET interrupt\n", instance->host_no));
1184 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1185 } else {
1186#if defined(REAL_DMA)
1187 /*
1188 * We should only get PHASE MISMATCH and EOP interrupts
1189 * if we have DMA enabled, so do a sanity check based on
1190 * the current setting of the MODE register.
1191 */
1192
1193 if ((NCR5380_read(MODE_REG) & MR_DMA) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) {
1194 int transferred;
1195
1196 if (!hostdata->connected)
1197 panic("scsi%d : received end of DMA interrupt with no connected cmd\n", instance->hostno);
1198
1199 transferred = (hostdata->dmalen - NCR5380_dma_residual(instance));
1200 hostdata->connected->SCp.this_residual -= transferred;
1201 hostdata->connected->SCp.ptr += transferred;
1202 hostdata->dmalen = 0;
1203
1204 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1205
1206 /* FIXME: we need to poll briefly then defer a workqueue task ! */
1207 NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2*HZ);
1208
1209 NCR5380_write(MODE_REG, MR_BASE);
1210 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1211 }
1212#else
1213 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)));
1214 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1215#endif
1216 }
1217 } /* if BASR_IRQ */
1218 spin_unlock_irqrestore(instance->host_lock, flags);
1219 if(!done)
1220 schedule_delayed_work(&hostdata->coroutine, 0);
1221 } while (!done);
1222 return IRQ_HANDLED;
1223}
1224
1225#endif
1226
1227/**
1228 * collect_stats - collect stats on a scsi command
1229 * @hostdata: adapter
1230 * @cmd: command being issued
1231 *
1232 * Update the statistical data by parsing the command in question
1233 */
1234
1235static void collect_stats(struct NCR5380_hostdata *hostdata, Scsi_Cmnd * cmd)
1236{
1237#ifdef NCR5380_STATS
1238 switch (cmd->cmnd[0]) {
1239 case WRITE:
1240 case WRITE_6:
1241 case WRITE_10:
1242 hostdata->time_write[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1243 hostdata->pendingw--;
1244 break;
1245 case READ:
1246 case READ_6:
1247 case READ_10:
1248 hostdata->time_read[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1249 hostdata->pendingr--;
1250 break;
1251 }
1252#endif
1253}
1254
1255
1256/*
1257 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1258 * int tag);
1259 *
1260 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1261 * including ARBITRATION, SELECTION, and initial message out for
1262 * IDENTIFY and queue messages.
1263 *
1264 * Inputs : instance - instantiation of the 5380 driver on which this
1265 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1266 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1267 * the command that is presently connected.
1268 *
1269 * Returns : -1 if selection could not execute for some reason,
1270 * 0 if selection succeeded or failed because the target
1271 * did not respond.
1272 *
1273 * Side effects :
1274 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1275 * with registers as they should have been on entry - ie
1276 * SELECT_ENABLE will be set appropriately, the NCR5380
1277 * will cease to drive any SCSI bus signals.
1278 *
1279 * If successful : I_T_L or I_T_L_Q nexus will be established,
1280 * instance->connected will be set to cmd.
1281 * SELECT interrupt will be disabled.
1282 *
1283 * If failed (no target) : cmd->scsi_done() will be called, and the
1284 * cmd->result host byte set to DID_BAD_TARGET.
1285 *
1286 * Locks: caller holds hostdata lock in IRQ mode
1287 */
1288
1289static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag)
1290{
1291 NCR5380_local_declare();
1292 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1293 unsigned char tmp[3], phase;
1294 unsigned char *data;
1295 int len;
1296 unsigned long timeout;
1297 unsigned char value;
1298 int err;
1299 NCR5380_setup(instance);
1300
1301 if (hostdata->selecting)
1302 goto part2;
1303
1304 hostdata->restart_select = 0;
1305
1306 NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1307 dprintk(NDEBUG_ARBITRATION, ("scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id));
1308
1309 /*
1310 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1311 * data bus during SELECTION.
1312 */
1313
1314 NCR5380_write(TARGET_COMMAND_REG, 0);
1315
1316 /*
1317 * Start arbitration.
1318 */
1319
1320 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1321 NCR5380_write(MODE_REG, MR_ARBITRATE);
1322
1323
1324 /* We can be relaxed here, interrupts are on, we are
1325 in workqueue context, the birds are singing in the trees */
1326 spin_unlock_irq(instance->host_lock);
1327 err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ);
1328 spin_lock_irq(instance->host_lock);
1329 if (err < 0) {
1330 printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__);
1331 NCR5380_write(MODE_REG, MR_BASE);
1332 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1333 goto failed;
1334 }
1335
1336 dprintk(NDEBUG_ARBITRATION, ("scsi%d : arbitration complete\n", instance->host_no));
1337
1338 /*
1339 * The arbitration delay is 2.2us, but this is a minimum and there is
1340 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1341 * the integral nature of udelay().
1342 *
1343 */
1344
1345 udelay(3);
1346
1347 /* Check for lost arbitration */
1348 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)) {
1349 NCR5380_write(MODE_REG, MR_BASE);
1350 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no));
1351 goto failed;
1352 }
1353 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL);
1354
1355 if (!(hostdata->flags & FLAG_DTC3181E) &&
1356 /* RvC: DTC3181E has some trouble with this
1357 * so we simply removed it. Seems to work with
1358 * only Mustek scanner attached
1359 */
1360 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1361 NCR5380_write(MODE_REG, MR_BASE);
1362 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1363 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no));
1364 goto failed;
1365 }
1366 /*
1367 * Again, bus clear + bus settle time is 1.2us, however, this is
1368 * a minimum so we'll udelay ceil(1.2)
1369 */
1370
1371 udelay(2);
1372
1373 dprintk(NDEBUG_ARBITRATION, ("scsi%d : won arbitration\n", instance->host_no));
1374
1375 /*
1376 * Now that we have won arbitration, start Selection process, asserting
1377 * the host and target ID's on the SCSI bus.
1378 */
1379
1380 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << scmd_id(cmd))));
1381
1382 /*
1383 * Raise ATN while SEL is true before BSY goes false from arbitration,
1384 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1385 * phase immediately after selection.
1386 */
1387
1388 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1389 NCR5380_write(MODE_REG, MR_BASE);
1390
1391 /*
1392 * Reselect interrupts must be turned off prior to the dropping of BSY,
1393 * otherwise we will trigger an interrupt.
1394 */
1395 NCR5380_write(SELECT_ENABLE_REG, 0);
1396
1397 /*
1398 * The initiator shall then wait at least two deskew delays and release
1399 * the BSY signal.
1400 */
1401 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1402
1403 /* Reset BSY */
1404 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1405
1406 /*
1407 * Something weird happens when we cease to drive BSY - looks
1408 * like the board/chip is letting us do another read before the
1409 * appropriate propagation delay has expired, and we're confusing
1410 * a BSY signal from ourselves as the target's response to SELECTION.
1411 *
1412 * A small delay (the 'C++' frontend breaks the pipeline with an
1413 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1414 * tighter 'C' code breaks and requires this) solves the problem -
1415 * the 1 us delay is arbitrary, and only used because this delay will
1416 * be the same on other platforms and since it works here, it should
1417 * work there.
1418 *
1419 * wingel suggests that this could be due to failing to wait
1420 * one deskew delay.
1421 */
1422
1423 udelay(1);
1424
1425 dprintk(NDEBUG_SELECTION, ("scsi%d : selecting target %d\n", instance->host_no, scmd_id(cmd)));
1426
1427 /*
1428 * The SCSI specification calls for a 250 ms timeout for the actual
1429 * selection.
1430 */
1431
1432 timeout = jiffies + (250 * HZ / 1000);
1433
1434 /*
1435 * XXX very interesting - we're seeing a bounce where the BSY we
1436 * asserted is being reflected / still asserted (propagation delay?)
1437 * and it's detecting as true. Sigh.
1438 */
1439
1440 hostdata->select_time = 0; /* we count the clock ticks at which we polled */
1441 hostdata->selecting = cmd;
1442
1443part2:
1444 /* RvC: here we enter after a sleeping period, or immediately after
1445 execution of part 1
1446 we poll only once ech clock tick */
1447 value = NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO);
1448
1449 if (!value && (hostdata->select_time < HZ/4)) {
1450 /* RvC: we still must wait for a device response */
1451 hostdata->select_time++; /* after 25 ticks the device has failed */
1452 NCR5380_set_timer(hostdata, 1);
1453 return 0; /* RvC: we return here with hostdata->selecting set,
1454 to go to sleep */
1455 }
1456
1457 hostdata->selecting = NULL;/* clear this pointer, because we passed the
1458 waiting period */
1459 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1460 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1461 NCR5380_reselect(instance);
1462 printk("scsi%d : reselection after won arbitration?\n", instance->host_no);
1463 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1464 return -1;
1465 }
1466 /*
1467 * No less than two deskew delays after the initiator detects the
1468 * BSY signal is true, it shall release the SEL signal and may
1469 * change the DATA BUS. -wingel
1470 */
1471
1472 udelay(1);
1473
1474 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1475
1476 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1477 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1478 if (hostdata->targets_present & (1 << scmd_id(cmd))) {
1479 printk(KERN_DEBUG "scsi%d : weirdness\n", instance->host_no);
1480 if (hostdata->restart_select)
1481 printk(KERN_DEBUG "\trestart select\n");
1482 NCR5380_dprint(NDEBUG_SELECTION, instance);
1483 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1484 return -1;
1485 }
1486 cmd->result = DID_BAD_TARGET << 16;
1487 collect_stats(hostdata, cmd);
1488 cmd->scsi_done(cmd);
1489 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1490 dprintk(NDEBUG_SELECTION, ("scsi%d : target did not respond within 250ms\n", instance->host_no));
1491 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1492 return 0;
1493 }
1494 hostdata->targets_present |= (1 << scmd_id(cmd));
1495
1496 /*
1497 * Since we followed the SCSI spec, and raised ATN while SEL
1498 * was true but before BSY was false during selection, the information
1499 * transfer phase should be a MESSAGE OUT phase so that we can send the
1500 * IDENTIFY message.
1501 *
1502 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1503 * message (2 bytes) with a tag ID that we increment with every command
1504 * until it wraps back to 0.
1505 *
1506 * XXX - it turns out that there are some broken SCSI-II devices,
1507 * which claim to support tagged queuing but fail when more than
1508 * some number of commands are issued at once.
1509 */
1510
1511 /* Wait for start of REQ/ACK handshake */
1512
1513 spin_unlock_irq(instance->host_lock);
1514 err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
1515 spin_lock_irq(instance->host_lock);
1516
1517 if(err) {
1518 printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__);
1519 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1520 goto failed;
1521 }
1522
1523 dprintk(NDEBUG_SELECTION, ("scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id));
1524 tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun);
1525
1526 len = 1;
1527 cmd->tag = 0;
1528
1529 /* Send message(s) */
1530 data = tmp;
1531 phase = PHASE_MSGOUT;
1532 NCR5380_transfer_pio(instance, &phase, &len, &data);
1533 dprintk(NDEBUG_SELECTION, ("scsi%d : nexus established.\n", instance->host_no));
1534 /* XXX need to handle errors here */
1535 hostdata->connected = cmd;
1536 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1537
1538 initialize_SCp(cmd);
1539
1540 return 0;
1541
1542 /* Selection failed */
1543failed:
1544 return -1;
1545
1546}
1547
1548/*
1549 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1550 * unsigned char *phase, int *count, unsigned char **data)
1551 *
1552 * Purpose : transfers data in given phase using polled I/O
1553 *
1554 * Inputs : instance - instance of driver, *phase - pointer to
1555 * what phase is expected, *count - pointer to number of
1556 * bytes to transfer, **data - pointer to data pointer.
1557 *
1558 * Returns : -1 when different phase is entered without transferring
1559 * maximum number of bytes, 0 if all bytes or transferred or exit
1560 * is in same phase.
1561 *
1562 * Also, *phase, *count, *data are modified in place.
1563 *
1564 * XXX Note : handling for bus free may be useful.
1565 */
1566
1567/*
1568 * Note : this code is not as quick as it could be, however it
1569 * IS 100% reliable, and for the actual data transfer where speed
1570 * counts, we will always do a pseudo DMA or DMA transfer.
1571 */
1572
1573static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1574 NCR5380_local_declare();
1575 unsigned char p = *phase, tmp;
1576 int c = *count;
1577 unsigned char *d = *data;
1578 /*
1579 * RvC: some administrative data to process polling time
1580 */
1581 int break_allowed = 0;
1582 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1583 NCR5380_setup(instance);
1584
1585 if (!(p & SR_IO))
1586 dprintk(NDEBUG_PIO, ("scsi%d : pio write %d bytes\n", instance->host_no, c));
1587 else
1588 dprintk(NDEBUG_PIO, ("scsi%d : pio read %d bytes\n", instance->host_no, c));
1589
1590 /*
1591 * The NCR5380 chip will only drive the SCSI bus when the
1592 * phase specified in the appropriate bits of the TARGET COMMAND
1593 * REGISTER match the STATUS REGISTER
1594 */
1595
1596 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1597
1598 /* RvC: don't know if this is necessary, but other SCSI I/O is short
1599 * so breaks are not necessary there
1600 */
1601 if ((p == PHASE_DATAIN) || (p == PHASE_DATAOUT)) {
1602 break_allowed = 1;
1603 }
1604 do {
1605 /*
1606 * Wait for assertion of REQ, after which the phase bits will be
1607 * valid
1608 */
1609
1610 /* RvC: we simply poll once, after that we stop temporarily
1611 * and let the device buffer fill up
1612 * if breaking is not allowed, we keep polling as long as needed
1613 */
1614
1615 /* FIXME */
1616 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ) && !break_allowed);
1617 if (!(tmp & SR_REQ)) {
1618 /* timeout condition */
1619 NCR5380_set_timer(hostdata, USLEEP_SLEEP);
1620 break;
1621 }
1622
1623 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : REQ detected\n", instance->host_no));
1624
1625 /* Check for phase mismatch */
1626 if ((tmp & PHASE_MASK) != p) {
1627 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : phase mismatch\n", instance->host_no));
1628 NCR5380_dprint_phase(NDEBUG_HANDSHAKE, instance);
1629 break;
1630 }
1631 /* Do actual transfer from SCSI bus to / from memory */
1632 if (!(p & SR_IO))
1633 NCR5380_write(OUTPUT_DATA_REG, *d);
1634 else
1635 *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1636
1637 ++d;
1638
1639 /*
1640 * The SCSI standard suggests that in MSGOUT phase, the initiator
1641 * should drop ATN on the last byte of the message phase
1642 * after REQ has been asserted for the handshake but before
1643 * the initiator raises ACK.
1644 */
1645
1646 if (!(p & SR_IO)) {
1647 if (!((p & SR_MSG) && c > 1)) {
1648 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1649 NCR5380_dprint(NDEBUG_PIO, instance);
1650 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1651 } else {
1652 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1653 NCR5380_dprint(NDEBUG_PIO, instance);
1654 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1655 }
1656 } else {
1657 NCR5380_dprint(NDEBUG_PIO, instance);
1658 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1659 }
1660
1661 /* FIXME - if this fails bus reset ?? */
1662 NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 5*HZ);
1663 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : req false, handshake complete\n", instance->host_no));
1664
1665/*
1666 * We have several special cases to consider during REQ/ACK handshaking :
1667 * 1. We were in MSGOUT phase, and we are on the last byte of the
1668 * message. ATN must be dropped as ACK is dropped.
1669 *
1670 * 2. We are in a MSGIN phase, and we are on the last byte of the
1671 * message. We must exit with ACK asserted, so that the calling
1672 * code may raise ATN before dropping ACK to reject the message.
1673 *
1674 * 3. ACK and ATN are clear and the target may proceed as normal.
1675 */
1676 if (!(p == PHASE_MSGIN && c == 1)) {
1677 if (p == PHASE_MSGOUT && c > 1)
1678 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1679 else
1680 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1681 }
1682 } while (--c);
1683
1684 dprintk(NDEBUG_PIO, ("scsi%d : residual %d\n", instance->host_no, c));
1685
1686 *count = c;
1687 *data = d;
1688 tmp = NCR5380_read(STATUS_REG);
1689 if (tmp & SR_REQ)
1690 *phase = tmp & PHASE_MASK;
1691 else
1692 *phase = PHASE_UNKNOWN;
1693
1694 if (!c || (*phase == p))
1695 return 0;
1696 else
1697 return -1;
1698}
1699
1700/**
1701 * do_reset - issue a reset command
1702 * @host: adapter to reset
1703 *
1704 * Issue a reset sequence to the NCR5380 and try and get the bus
1705 * back into sane shape.
1706 *
1707 * Locks: caller holds queue lock
1708 */
1709
1710static void do_reset(struct Scsi_Host *host) {
1711 NCR5380_local_declare();
1712 NCR5380_setup(host);
1713
1714 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
1715 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
1716 udelay(25);
1717 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1718}
1719
1720/*
1721 * Function : do_abort (Scsi_Host *host)
1722 *
1723 * Purpose : abort the currently established nexus. Should only be
1724 * called from a routine which can drop into a
1725 *
1726 * Returns : 0 on success, -1 on failure.
1727 *
1728 * Locks: queue lock held by caller
1729 * FIXME: sort this out and get new_eh running
1730 */
1731
1732static int do_abort(struct Scsi_Host *host) {
1733 NCR5380_local_declare();
1734 unsigned char *msgptr, phase, tmp;
1735 int len;
1736 int rc;
1737 NCR5380_setup(host);
1738
1739
1740 /* Request message out phase */
1741 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1742
1743 /*
1744 * Wait for the target to indicate a valid phase by asserting
1745 * REQ. Once this happens, we'll have either a MSGOUT phase
1746 * and can immediately send the ABORT message, or we'll have some
1747 * other phase and will have to source/sink data.
1748 *
1749 * We really don't care what value was on the bus or what value
1750 * the target sees, so we just handshake.
1751 */
1752
1753 rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, SR_REQ, 60 * HZ);
1754
1755 if(rc < 0)
1756 return -1;
1757
1758 tmp = (unsigned char)rc;
1759
1760 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1761
1762 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1763 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1764 rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, 0, 3*HZ);
1765 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1766 if(rc == -1)
1767 return -1;
1768 }
1769 tmp = ABORT;
1770 msgptr = &tmp;
1771 len = 1;
1772 phase = PHASE_MSGOUT;
1773 NCR5380_transfer_pio(host, &phase, &len, &msgptr);
1774
1775 /*
1776 * If we got here, and the command completed successfully,
1777 * we're about to go into bus free state.
1778 */
1779
1780 return len ? -1 : 0;
1781}
1782
1783#if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL)
1784/*
1785 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1786 * unsigned char *phase, int *count, unsigned char **data)
1787 *
1788 * Purpose : transfers data in given phase using either real
1789 * or pseudo DMA.
1790 *
1791 * Inputs : instance - instance of driver, *phase - pointer to
1792 * what phase is expected, *count - pointer to number of
1793 * bytes to transfer, **data - pointer to data pointer.
1794 *
1795 * Returns : -1 when different phase is entered without transferring
1796 * maximum number of bytes, 0 if all bytes or transferred or exit
1797 * is in same phase.
1798 *
1799 * Also, *phase, *count, *data are modified in place.
1800 *
1801 * Locks: io_request lock held by caller
1802 */
1803
1804
1805static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1806 NCR5380_local_declare();
1807 register int c = *count;
1808 register unsigned char p = *phase;
1809 register unsigned char *d = *data;
1810 unsigned char tmp;
1811 int foo;
1812#if defined(REAL_DMA_POLL)
1813 int cnt, toPIO;
1814 unsigned char saved_data = 0, overrun = 0, residue;
1815#endif
1816
1817 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1818
1819 NCR5380_setup(instance);
1820
1821 if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1822 *phase = tmp;
1823 return -1;
1824 }
1825#if defined(REAL_DMA) || defined(REAL_DMA_POLL)
1826#ifdef READ_OVERRUNS
1827 if (p & SR_IO) {
1828 c -= 2;
1829 }
1830#endif
1831 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));
1832 hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c);
1833#endif
1834
1835 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1836
1837#ifdef REAL_DMA
1838 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1839#elif defined(REAL_DMA_POLL)
1840 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1841#else
1842 /*
1843 * Note : on my sample board, watch-dog timeouts occurred when interrupts
1844 * were not disabled for the duration of a single DMA transfer, from
1845 * before the setting of DMA mode to after transfer of the last byte.
1846 */
1847
1848#if defined(PSEUDO_DMA) && defined(UNSAFE)
1849 spin_unlock_irq(instance->host_lock);
1850#endif
1851 /* KLL May need eop and parity in 53c400 */
1852 if (hostdata->flags & FLAG_NCR53C400)
1853 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE |
1854 MR_ENABLE_PAR_CHECK | MR_ENABLE_PAR_INTR |
1855 MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1856 else
1857 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1858#endif /* def REAL_DMA */
1859
1860 dprintk(NDEBUG_DMA, ("scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG)));
1861
1862 /*
1863 * On the PAS16 at least I/O recovery delays are not needed here.
1864 * Everyone else seems to want them.
1865 */
1866
1867 if (p & SR_IO) {
1868 io_recovery_delay(1);
1869 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1870 } else {
1871 io_recovery_delay(1);
1872 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1873 io_recovery_delay(1);
1874 NCR5380_write(START_DMA_SEND_REG, 0);
1875 io_recovery_delay(1);
1876 }
1877
1878#if defined(REAL_DMA_POLL)
1879 do {
1880 tmp = NCR5380_read(BUS_AND_STATUS_REG);
1881 } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER)));
1882
1883/*
1884 At this point, either we've completed DMA, or we have a phase mismatch,
1885 or we've unexpectedly lost BUSY (which is a real error).
1886
1887 For write DMAs, we want to wait until the last byte has been
1888 transferred out over the bus before we turn off DMA mode. Alas, there
1889 seems to be no terribly good way of doing this on a 5380 under all
1890 conditions. For non-scatter-gather operations, we can wait until REQ
1891 and ACK both go false, or until a phase mismatch occurs. Gather-writes
1892 are nastier, since the device will be expecting more data than we
1893 are prepared to send it, and REQ will remain asserted. On a 53C8[01] we
1894 could test LAST BIT SENT to assure transfer (I imagine this is precisely
1895 why this signal was added to the newer chips) but on the older 538[01]
1896 this signal does not exist. The workaround for this lack is a watchdog;
1897 we bail out of the wait-loop after a modest amount of wait-time if
1898 the usual exit conditions are not met. Not a terribly clean or
1899 correct solution :-%
1900
1901 Reads are equally tricky due to a nasty characteristic of the NCR5380.
1902 If the chip is in DMA mode for an READ, it will respond to a target's
1903 REQ by latching the SCSI data into the INPUT DATA register and asserting
1904 ACK, even if it has _already_ been notified by the DMA controller that
1905 the current DMA transfer has completed! If the NCR5380 is then taken
1906 out of DMA mode, this already-acknowledged byte is lost.
1907
1908 This is not a problem for "one DMA transfer per command" reads, because
1909 the situation will never arise... either all of the data is DMA'ed
1910 properly, or the target switches to MESSAGE IN phase to signal a
1911 disconnection (either operation bringing the DMA to a clean halt).
1912 However, in order to handle scatter-reads, we must work around the
1913 problem. The chosen fix is to DMA N-2 bytes, then check for the
1914 condition before taking the NCR5380 out of DMA mode. One or two extra
1915 bytes are transferred via PIO as necessary to fill out the original
1916 request.
1917 */
1918
1919 if (p & SR_IO) {
1920#ifdef READ_OVERRUNS
1921 udelay(10);
1922 if (((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == (BASR_PHASE_MATCH | BASR_ACK))) {
1923 saved_data = NCR5380_read(INPUT_DATA_REGISTER);
1924 overrun = 1;
1925 }
1926#endif
1927 } else {
1928 int limit = 100;
1929 while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) {
1930 if (!(tmp & BASR_PHASE_MATCH))
1931 break;
1932 if (--limit < 0)
1933 break;
1934 }
1935 }
1936
1937 dprintk(NDEBUG_DMA, ("scsi%d : polled DMA transfer complete, basr 0x%X, sr 0x%X\n", instance->host_no, tmp, NCR5380_read(STATUS_REG)));
1938
1939 NCR5380_write(MODE_REG, MR_BASE);
1940 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1941
1942 residue = NCR5380_dma_residual(instance);
1943 c -= residue;
1944 *count -= c;
1945 *data += c;
1946 *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
1947
1948#ifdef READ_OVERRUNS
1949 if (*phase == p && (p & SR_IO) && residue == 0) {
1950 if (overrun) {
1951 dprintk(NDEBUG_DMA, ("Got an input overrun, using saved byte\n"));
1952 **data = saved_data;
1953 *data += 1;
1954 *count -= 1;
1955 cnt = toPIO = 1;
1956 } else {
1957 printk("No overrun??\n");
1958 cnt = toPIO = 2;
1959 }
1960 dprintk(NDEBUG_DMA, ("Doing %d-byte PIO to 0x%X\n", cnt, *data));
1961 NCR5380_transfer_pio(instance, phase, &cnt, data);
1962 *count -= toPIO - cnt;
1963 }
1964#endif
1965
1966 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)));
1967 return 0;
1968
1969#elif defined(REAL_DMA)
1970 return 0;
1971#else /* defined(REAL_DMA_POLL) */
1972 if (p & SR_IO) {
1973#ifdef DMA_WORKS_RIGHT
1974 foo = NCR5380_pread(instance, d, c);
1975#else
1976 int diff = 1;
1977 if (hostdata->flags & FLAG_NCR53C400) {
1978 diff = 0;
1979 }
1980 if (!(foo = NCR5380_pread(instance, d, c - diff))) {
1981 /*
1982 * We can't disable DMA mode after successfully transferring
1983 * what we plan to be the last byte, since that would open up
1984 * a race condition where if the target asserted REQ before
1985 * we got the DMA mode reset, the NCR5380 would have latched
1986 * an additional byte into the INPUT DATA register and we'd
1987 * have dropped it.
1988 *
1989 * The workaround was to transfer one fewer bytes than we
1990 * intended to with the pseudo-DMA read function, wait for
1991 * the chip to latch the last byte, read it, and then disable
1992 * pseudo-DMA mode.
1993 *
1994 * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
1995 * REQ is deasserted when ACK is asserted, and not reasserted
1996 * until ACK goes false. Since the NCR5380 won't lower ACK
1997 * until DACK is asserted, which won't happen unless we twiddle
1998 * the DMA port or we take the NCR5380 out of DMA mode, we
1999 * can guarantee that we won't handshake another extra
2000 * byte.
2001 */
2002
2003 if (!(hostdata->flags & FLAG_NCR53C400)) {
2004 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ));
2005 /* Wait for clean handshake */
2006 while (NCR5380_read(STATUS_REG) & SR_REQ);
2007 d[c - 1] = NCR5380_read(INPUT_DATA_REG);
2008 }
2009 }
2010#endif
2011 } else {
2012#ifdef DMA_WORKS_RIGHT
2013 foo = NCR5380_pwrite(instance, d, c);
2014#else
2015 int timeout;
2016 dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c));
2017 if (!(foo = NCR5380_pwrite(instance, d, c))) {
2018 /*
2019 * Wait for the last byte to be sent. If REQ is being asserted for
2020 * the byte we're interested, we'll ACK it and it will go false.
2021 */
2022 if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) {
2023 timeout = 20000;
2024 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH));
2025
2026 if (!timeout)
2027 dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no));
2028
2029 if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) {
2030 hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT;
2031 if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) {
2032 hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT;
2033 dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no));
2034 }
2035 }
2036 } else {
2037 dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n"));
2038 while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT));
2039 dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n"));
2040 }
2041 }
2042#endif
2043 }
2044 NCR5380_write(MODE_REG, MR_BASE);
2045 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2046
2047 if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) {
2048 dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n"));
2049 if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) {
2050 dprintk(NDEBUG_C400_PWRITE, ("53C400w: got it, reading reset interrupt reg\n"));
2051 NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2052 } else {
2053 printk("53C400w: IRQ NOT THERE!\n");
2054 }
2055 }
2056 *data = d + c;
2057 *count = 0;
2058 *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
2059#if defined(PSEUDO_DMA) && defined(UNSAFE)
2060 spin_lock_irq(instance->host_lock);
2061#endif /* defined(REAL_DMA_POLL) */
2062 return foo;
2063#endif /* def REAL_DMA */
2064}
2065#endif /* defined(REAL_DMA) | defined(PSEUDO_DMA) */
2066
2067/*
2068 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
2069 *
2070 * Purpose : run through the various SCSI phases and do as the target
2071 * directs us to. Operates on the currently connected command,
2072 * instance->connected.
2073 *
2074 * Inputs : instance, instance for which we are doing commands
2075 *
2076 * Side effects : SCSI things happen, the disconnected queue will be
2077 * modified if a command disconnects, *instance->connected will
2078 * change.
2079 *
2080 * XXX Note : we need to watch for bus free or a reset condition here
2081 * to recover from an unexpected bus free condition.
2082 *
2083 * Locks: io_request_lock held by caller in IRQ mode
2084 */
2085
2086static void NCR5380_information_transfer(struct Scsi_Host *instance) {
2087 NCR5380_local_declare();
2088 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata;
2089 unsigned char msgout = NOP;
2090 int sink = 0;
2091 int len;
2092#if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2093 int transfersize;
2094#endif
2095 unsigned char *data;
2096 unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2097 Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2098 /* RvC: we need to set the end of the polling time */
2099 unsigned long poll_time = jiffies + USLEEP_POLL;
2100
2101 NCR5380_setup(instance);
2102
2103 while (1) {
2104 tmp = NCR5380_read(STATUS_REG);
2105 /* We only have a valid SCSI phase when REQ is asserted */
2106 if (tmp & SR_REQ) {
2107 phase = (tmp & PHASE_MASK);
2108 if (phase != old_phase) {
2109 old_phase = phase;
2110 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
2111 }
2112 if (sink && (phase != PHASE_MSGOUT)) {
2113 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2114
2115 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
2116 while (NCR5380_read(STATUS_REG) & SR_REQ);
2117 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2118 sink = 0;
2119 continue;
2120 }
2121 switch (phase) {
2122 case PHASE_DATAIN:
2123 case PHASE_DATAOUT:
2124#if (NDEBUG & NDEBUG_NO_DATAOUT)
2125 printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no);
2126 sink = 1;
2127 do_abort(instance);
2128 cmd->result = DID_ERROR << 16;
2129 cmd->scsi_done(cmd);
2130 return;
2131#endif
2132 /*
2133 * If there is no room left in the current buffer in the
2134 * scatter-gather list, move onto the next one.
2135 */
2136
2137 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2138 ++cmd->SCp.buffer;
2139 --cmd->SCp.buffers_residual;
2140 cmd->SCp.this_residual = cmd->SCp.buffer->length;
2141 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2142 dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual));
2143 }
2144 /*
2145 * The preferred transfer method is going to be
2146 * PSEUDO-DMA for systems that are strictly PIO,
2147 * since we can let the hardware do the handshaking.
2148 *
2149 * For this to work, we need to know the transfersize
2150 * ahead of time, since the pseudo-DMA code will sit
2151 * in an unconditional loop.
2152 */
2153
2154#if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2155 /* KLL
2156 * PSEUDO_DMA is defined here. If this is the g_NCR5380
2157 * driver then it will always be defined, so the
2158 * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base
2159 * NCR5380 case. I think this is a fairly clean solution.
2160 * We supplement these 2 if's with the flag.
2161 */
2162#ifdef NCR5380_dma_xfer_len
2163 if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) {
2164#else
2165 transfersize = cmd->transfersize;
2166
2167#ifdef LIMIT_TRANSFERSIZE /* If we have problems with interrupt service */
2168 if (transfersize > 512)
2169 transfersize = 512;
2170#endif /* LIMIT_TRANSFERSIZE */
2171
2172 if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) {
2173 /* Limit transfers to 32K, for xx400 & xx406
2174 * pseudoDMA that transfers in 128 bytes blocks. */
2175 if (transfersize > 32 * 1024)
2176 transfersize = 32 * 1024;
2177#endif
2178 len = transfersize;
2179 if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) {
2180 /*
2181 * If the watchdog timer fires, all future accesses to this
2182 * device will use the polled-IO.
2183 */
2184 scmd_printk(KERN_INFO, cmd,
2185 "switching to slow handshake\n");
2186 cmd->device->borken = 1;
2187 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2188 sink = 1;
2189 do_abort(instance);
2190 cmd->result = DID_ERROR << 16;
2191 cmd->scsi_done(cmd);
2192 /* XXX - need to source or sink data here, as appropriate */
2193 } else
2194 cmd->SCp.this_residual -= transfersize - len;
2195 } else
2196#endif /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */
2197 NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **)
2198 &cmd->SCp.ptr);
2199 break;
2200 case PHASE_MSGIN:
2201 len = 1;
2202 data = &tmp;
2203 NCR5380_transfer_pio(instance, &phase, &len, &data);
2204 cmd->SCp.Message = tmp;
2205
2206 switch (tmp) {
2207 /*
2208 * Linking lets us reduce the time required to get the
2209 * next command out to the device, hopefully this will
2210 * mean we don't waste another revolution due to the delays
2211 * required by ARBITRATION and another SELECTION.
2212 *
2213 * In the current implementation proposal, low level drivers
2214 * merely have to start the next command, pointed to by
2215 * next_link, done() is called as with unlinked commands.
2216 */
2217#ifdef LINKED
2218 case LINKED_CMD_COMPLETE:
2219 case LINKED_FLG_CMD_COMPLETE:
2220 /* Accept message by clearing ACK */
2221 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2222 dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun));
2223 /*
2224 * Sanity check : A linked command should only terminate with
2225 * one of these messages if there are more linked commands
2226 * available.
2227 */
2228 if (!cmd->next_link) {
2229 printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun);
2230 sink = 1;
2231 do_abort(instance);
2232 return;
2233 }
2234 initialize_SCp(cmd->next_link);
2235 /* The next command is still part of this process */
2236 cmd->next_link->tag = cmd->tag;
2237 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2238 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));
2239 collect_stats(hostdata, cmd);
2240 cmd->scsi_done(cmd);
2241 cmd = hostdata->connected;
2242 break;
2243#endif /* def LINKED */
2244 case ABORT:
2245 case COMMAND_COMPLETE:
2246 /* Accept message by clearing ACK */
2247 sink = 1;
2248 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2249 hostdata->connected = NULL;
2250 dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun));
2251 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2252
2253 /*
2254 * I'm not sure what the correct thing to do here is :
2255 *
2256 * If the command that just executed is NOT a request
2257 * sense, the obvious thing to do is to set the result
2258 * code to the values of the stored parameters.
2259 *
2260 * If it was a REQUEST SENSE command, we need some way
2261 * to differentiate between the failure code of the original
2262 * and the failure code of the REQUEST sense - the obvious
2263 * case is success, where we fall through and leave the result
2264 * code unchanged.
2265 *
2266 * The non-obvious place is where the REQUEST SENSE failed
2267 */
2268
2269 if (cmd->cmnd[0] != REQUEST_SENSE)
2270 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2271 else if (status_byte(cmd->SCp.Status) != GOOD)
2272 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2273
2274#ifdef AUTOSENSE
2275 if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2276 hostdata->ses.cmd_len) {
2277 scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2278 hostdata->ses.cmd_len = 0 ;
2279 }
2280
2281 if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2282 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2283
2284 dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no));
2285
2286 LIST(cmd, hostdata->issue_queue);
2287 cmd->host_scribble = (unsigned char *)
2288 hostdata->issue_queue;
2289 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2290 dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no));
2291 } else
2292#endif /* def AUTOSENSE */
2293 {
2294 collect_stats(hostdata, cmd);
2295 cmd->scsi_done(cmd);
2296 }
2297
2298 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2299 /*
2300 * Restore phase bits to 0 so an interrupted selection,
2301 * arbitration can resume.
2302 */
2303 NCR5380_write(TARGET_COMMAND_REG, 0);
2304
2305 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2306 barrier();
2307 return;
2308 case MESSAGE_REJECT:
2309 /* Accept message by clearing ACK */
2310 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2311 switch (hostdata->last_message) {
2312 case HEAD_OF_QUEUE_TAG:
2313 case ORDERED_QUEUE_TAG:
2314 case SIMPLE_QUEUE_TAG:
2315 cmd->device->simple_tags = 0;
2316 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2317 break;
2318 default:
2319 break;
2320 }
2321 case DISCONNECT:{
2322 /* Accept message by clearing ACK */
2323 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2324 cmd->device->disconnect = 1;
2325 LIST(cmd, hostdata->disconnected_queue);
2326 cmd->host_scribble = (unsigned char *)
2327 hostdata->disconnected_queue;
2328 hostdata->connected = NULL;
2329 hostdata->disconnected_queue = cmd;
2330 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));
2331 /*
2332 * Restore phase bits to 0 so an interrupted selection,
2333 * arbitration can resume.
2334 */
2335 NCR5380_write(TARGET_COMMAND_REG, 0);
2336
2337 /* Enable reselect interrupts */
2338 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2339 /* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/
2340 /* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */
2341 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2342 barrier();
2343 return;
2344 }
2345 /*
2346 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2347 * operation, in violation of the SCSI spec so we can safely
2348 * ignore SAVE/RESTORE pointers calls.
2349 *
2350 * Unfortunately, some disks violate the SCSI spec and
2351 * don't issue the required SAVE_POINTERS message before
2352 * disconnecting, and we have to break spec to remain
2353 * compatible.
2354 */
2355 case SAVE_POINTERS:
2356 case RESTORE_POINTERS:
2357 /* Accept message by clearing ACK */
2358 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2359 break;
2360 case EXTENDED_MESSAGE:
2361/*
2362 * Extended messages are sent in the following format :
2363 * Byte
2364 * 0 EXTENDED_MESSAGE == 1
2365 * 1 length (includes one byte for code, doesn't
2366 * include first two bytes)
2367 * 2 code
2368 * 3..length+1 arguments
2369 *
2370 * Start the extended message buffer with the EXTENDED_MESSAGE
2371 * byte, since spi_print_msg() wants the whole thing.
2372 */
2373 extended_msg[0] = EXTENDED_MESSAGE;
2374 /* Accept first byte by clearing ACK */
2375 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2376 dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no));
2377
2378 len = 2;
2379 data = extended_msg + 1;
2380 phase = PHASE_MSGIN;
2381 NCR5380_transfer_pio(instance, &phase, &len, &data);
2382
2383 dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2]));
2384
2385 if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) {
2386 /* Accept third byte by clearing ACK */
2387 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2388 len = extended_msg[1] - 1;
2389 data = extended_msg + 3;
2390 phase = PHASE_MSGIN;
2391
2392 NCR5380_transfer_pio(instance, &phase, &len, &data);
2393 dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len));
2394
2395 switch (extended_msg[2]) {
2396 case EXTENDED_SDTR:
2397 case EXTENDED_WDTR:
2398 case EXTENDED_MODIFY_DATA_POINTER:
2399 case EXTENDED_EXTENDED_IDENTIFY:
2400 tmp = 0;
2401 }
2402 } else if (len) {
2403 printk("scsi%d: error receiving extended message\n", instance->host_no);
2404 tmp = 0;
2405 } else {
2406 printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]);
2407 tmp = 0;
2408 }
2409 /* Fall through to reject message */
2410
2411 /*
2412 * If we get something weird that we aren't expecting,
2413 * reject it.
2414 */
2415 default:
2416 if (!tmp) {
2417 printk("scsi%d: rejecting message ", instance->host_no);
2418 spi_print_msg(extended_msg);
2419 printk("\n");
2420 } else if (tmp != EXTENDED_MESSAGE)
2421 scmd_printk(KERN_INFO, cmd,
2422 "rejecting unknown message %02x\n",tmp);
2423 else
2424 scmd_printk(KERN_INFO, cmd,
2425 "rejecting unknown extended message code %02x, length %d\n", extended_msg[1], extended_msg[0]);
2426
2427 msgout = MESSAGE_REJECT;
2428 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2429 break;
2430 } /* switch (tmp) */
2431 break;
2432 case PHASE_MSGOUT:
2433 len = 1;
2434 data = &msgout;
2435 hostdata->last_message = msgout;
2436 NCR5380_transfer_pio(instance, &phase, &len, &data);
2437 if (msgout == ABORT) {
2438 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2439 hostdata->connected = NULL;
2440 cmd->result = DID_ERROR << 16;
2441 collect_stats(hostdata, cmd);
2442 cmd->scsi_done(cmd);
2443 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2444 return;
2445 }
2446 msgout = NOP;
2447 break;
2448 case PHASE_CMDOUT:
2449 len = cmd->cmd_len;
2450 data = cmd->cmnd;
2451 /*
2452 * XXX for performance reasons, on machines with a
2453 * PSEUDO-DMA architecture we should probably
2454 * use the dma transfer function.
2455 */
2456 NCR5380_transfer_pio(instance, &phase, &len, &data);
2457 if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) {
2458 NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2459 dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2460 return;
2461 }
2462 break;
2463 case PHASE_STATIN:
2464 len = 1;
2465 data = &tmp;
2466 NCR5380_transfer_pio(instance, &phase, &len, &data);
2467 cmd->SCp.Status = tmp;
2468 break;
2469 default:
2470 printk("scsi%d : unknown phase\n", instance->host_no);
2471 NCR5380_dprint(NDEBUG_ALL, instance);
2472 } /* switch(phase) */
2473 } /* if (tmp * SR_REQ) */
2474 else {
2475 /* RvC: go to sleep if polling time expired
2476 */
2477 if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) {
2478 NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2479 dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2480 return;
2481 }
2482 }
2483 } /* while (1) */
2484}
2485
2486/*
2487 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2488 *
2489 * Purpose : does reselection, initializing the instance->connected
2490 * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2491 * nexus has been reestablished,
2492 *
2493 * Inputs : instance - this instance of the NCR5380.
2494 *
2495 * Locks: io_request_lock held by caller if IRQ driven
2496 */
2497
2498static void NCR5380_reselect(struct Scsi_Host *instance) {
2499 NCR5380_local_declare();
2500 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)
2501 instance->hostdata;
2502 unsigned char target_mask;
2503 unsigned char lun, phase;
2504 int len;
2505 unsigned char msg[3];
2506 unsigned char *data;
2507 Scsi_Cmnd *tmp = NULL, *prev;
2508 int abort = 0;
2509 NCR5380_setup(instance);
2510
2511 /*
2512 * Disable arbitration, etc. since the host adapter obviously
2513 * lost, and tell an interrupted NCR5380_select() to restart.
2514 */
2515
2516 NCR5380_write(MODE_REG, MR_BASE);
2517 hostdata->restart_select = 1;
2518
2519 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2520 dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no));
2521
2522 /*
2523 * At this point, we have detected that our SCSI ID is on the bus,
2524 * SEL is true and BSY was false for at least one bus settle delay
2525 * (400 ns).
2526 *
2527 * We must assert BSY ourselves, until the target drops the SEL
2528 * signal.
2529 */
2530
2531 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2532
2533 /* FIXME: timeout too long, must fail to workqueue */
2534 if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0)
2535 abort = 1;
2536
2537 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2538
2539 /*
2540 * Wait for target to go into MSGIN.
2541 * FIXME: timeout needed and fail to work queeu
2542 */
2543
2544 if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ))
2545 abort = 1;
2546
2547 len = 1;
2548 data = msg;
2549 phase = PHASE_MSGIN;
2550 NCR5380_transfer_pio(instance, &phase, &len, &data);
2551
2552 if (!(msg[0] & 0x80)) {
2553 printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no);
2554 spi_print_msg(msg);
2555 abort = 1;
2556 } else {
2557 /* Accept message by clearing ACK */
2558 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2559 lun = (msg[0] & 0x07);
2560
2561 /*
2562 * We need to add code for SCSI-II to track which devices have
2563 * I_T_L_Q nexuses established, and which have simple I_T_L
2564 * nexuses so we can chose to do additional data transfer.
2565 */
2566
2567 /*
2568 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2569 * just reestablished, and remove it from the disconnected queue.
2570 */
2571
2572
2573 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
2574 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2575 ) {
2576 if (prev) {
2577 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
2578 prev->host_scribble = tmp->host_scribble;
2579 } else {
2580 REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble);
2581 hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble;
2582 }
2583 tmp->host_scribble = NULL;
2584 break;
2585 }
2586 if (!tmp) {
2587 printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun);
2588 /*
2589 * Since we have an established nexus that we can't do anything with,
2590 * we must abort it.
2591 */
2592 abort = 1;
2593 }
2594 }
2595
2596 if (abort) {
2597 do_abort(instance);
2598 } else {
2599 hostdata->connected = tmp;
2600 dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag));
2601 }
2602}
2603
2604/*
2605 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
2606 *
2607 * Purpose : called by interrupt handler when DMA finishes or a phase
2608 * mismatch occurs (which would finish the DMA transfer).
2609 *
2610 * Inputs : instance - this instance of the NCR5380.
2611 *
2612 * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L
2613 * nexus has been reestablished, on failure NULL is returned.
2614 */
2615
2616#ifdef REAL_DMA
2617static void NCR5380_dma_complete(NCR5380_instance * instance) {
2618 NCR5380_local_declare();
2619 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2620 int transferred;
2621 NCR5380_setup(instance);
2622
2623 /*
2624 * XXX this might not be right.
2625 *
2626 * Wait for final byte to transfer, ie wait for ACK to go false.
2627 *
2628 * We should use the Last Byte Sent bit, unfortunately this is
2629 * not available on the 5380/5381 (only the various CMOS chips)
2630 *
2631 * FIXME: timeout, and need to handle long timeout/irq case
2632 */
2633
2634 NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ);
2635
2636 NCR5380_write(MODE_REG, MR_BASE);
2637 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2638
2639 /*
2640 * The only places we should see a phase mismatch and have to send
2641 * data from the same set of pointers will be the data transfer
2642 * phases. So, residual, requested length are only important here.
2643 */
2644
2645 if (!(hostdata->connected->SCp.phase & SR_CD)) {
2646 transferred = instance->dmalen - NCR5380_dma_residual();
2647 hostdata->connected->SCp.this_residual -= transferred;
2648 hostdata->connected->SCp.ptr += transferred;
2649 }
2650}
2651#endif /* def REAL_DMA */
2652
2653/*
2654 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2655 *
2656 * Purpose : abort a command
2657 *
2658 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2659 * host byte of the result field to, if zero DID_ABORTED is
2660 * used.
2661 *
2662 * Returns : 0 - success, -1 on failure.
2663 *
2664 * XXX - there is no way to abort the command that is currently
2665 * connected, you have to wait for it to complete. If this is
2666 * a problem, we could implement longjmp() / setjmp(), setjmp()
2667 * called where the loop started in NCR5380_main().
2668 *
2669 * Locks: host lock taken by caller
2670 */
2671
2672static int NCR5380_abort(Scsi_Cmnd * cmd) {
2673 NCR5380_local_declare();
2674 struct Scsi_Host *instance = cmd->device->host;
2675 struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2676 Scsi_Cmnd *tmp, **prev;
2677
2678 printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no);
2679 scsi_print_command(cmd);
2680
2681 NCR5380_print_status(instance);
2682
2683 NCR5380_setup(instance);
2684
2685 dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no));
2686 dprintk(NDEBUG_ABORT, (" basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)));
2687
2688#if 0
2689/*
2690 * Case 1 : If the command is the currently executing command,
2691 * we'll set the aborted flag and return control so that
2692 * information transfer routine can exit cleanly.
2693 */
2694
2695 if (hostdata->connected == cmd) {
2696 dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no));
2697 hostdata->aborted = 1;
2698/*
2699 * We should perform BSY checking, and make sure we haven't slipped
2700 * into BUS FREE.
2701 */
2702
2703 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN);
2704/*
2705 * Since we can't change phases until we've completed the current
2706 * handshake, we have to source or sink a byte of data if the current
2707 * phase is not MSGOUT.
2708 */
2709
2710/*
2711 * Return control to the executing NCR drive so we can clear the
2712 * aborted flag and get back into our main loop.
2713 */
2714
2715 return 0;
2716 }
2717#endif
2718
2719/*
2720 * Case 2 : If the command hasn't been issued yet, we simply remove it
2721 * from the issue queue.
2722 */
2723
2724 dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no));
2725 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)
2726 if (cmd == tmp) {
2727 REMOVE(5, *prev, tmp, tmp->host_scribble);
2728 (*prev) = (Scsi_Cmnd *) tmp->host_scribble;
2729 tmp->host_scribble = NULL;
2730 tmp->result = DID_ABORT << 16;
2731 dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no));
2732 tmp->scsi_done(tmp);
2733 return SUCCESS;
2734 }
2735#if (NDEBUG & NDEBUG_ABORT)
2736 /* KLL */
2737 else if (prev == tmp)
2738 printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no);
2739#endif
2740
2741/*
2742 * Case 3 : If any commands are connected, we're going to fail the abort
2743 * and let the high level SCSI driver retry at a later time or
2744 * issue a reset.
2745 *
2746 * Timeouts, and therefore aborted commands, will be highly unlikely
2747 * and handling them cleanly in this situation would make the common
2748 * case of noresets less efficient, and would pollute our code. So,
2749 * we fail.
2750 */
2751
2752 if (hostdata->connected) {
2753 dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no));
2754 return FAILED;
2755 }
2756/*
2757 * Case 4: If the command is currently disconnected from the bus, and
2758 * there are no connected commands, we reconnect the I_T_L or
2759 * I_T_L_Q nexus associated with it, go into message out, and send
2760 * an abort message.
2761 *
2762 * This case is especially ugly. In order to reestablish the nexus, we
2763 * need to call NCR5380_select(). The easiest way to implement this
2764 * function was to abort if the bus was busy, and let the interrupt
2765 * handler triggered on the SEL for reselect take care of lost arbitrations
2766 * where necessary, meaning interrupts need to be enabled.
2767 *
2768 * When interrupts are enabled, the queues may change - so we
2769 * can't remove it from the disconnected queue before selecting it
2770 * because that could cause a failure in hashing the nexus if that
2771 * device reselected.
2772 *
2773 * Since the queues may change, we can't use the pointers from when we
2774 * first locate it.
2775 *
2776 * So, we must first locate the command, and if NCR5380_select()
2777 * succeeds, then issue the abort, relocate the command and remove
2778 * it from the disconnected queue.
2779 */
2780
2781 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble)
2782 if (cmd == tmp) {
2783 dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no));
2784
2785 if (NCR5380_select(instance, cmd, (int) cmd->tag))
2786 return FAILED;
2787 dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no));
2788
2789 do_abort(instance);
2790
2791 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)
2792 if (cmd == tmp) {
2793 REMOVE(5, *prev, tmp, tmp->host_scribble);
2794 *prev = (Scsi_Cmnd *) tmp->host_scribble;
2795 tmp->host_scribble = NULL;
2796 tmp->result = DID_ABORT << 16;
2797 tmp->scsi_done(tmp);
2798 return SUCCESS;
2799 }
2800 }
2801/*
2802 * Case 5 : If we reached this point, the command was not found in any of
2803 * the queues.
2804 *
2805 * We probably reached this point because of an unlikely race condition
2806 * between the command completing successfully and the abortion code,
2807 * so we won't panic, but we will notify the user in case something really
2808 * broke.
2809 */
2810 printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n"
2811 " before abortion\n", instance->host_no);
2812 return FAILED;
2813}
2814
2815
2816/*
2817 * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd)
2818 *
2819 * Purpose : reset the SCSI bus.
2820 *
2821 * Returns : SUCCESS
2822 *
2823 * Locks: host lock taken by caller
2824 */
2825
2826static int NCR5380_bus_reset(Scsi_Cmnd * cmd)
2827{
2828 struct Scsi_Host *instance = cmd->device->host;
2829
2830 NCR5380_local_declare();
2831 NCR5380_setup(instance);
2832 NCR5380_print_status(instance);
2833
2834 spin_lock_irq(instance->host_lock);
2835 do_reset(instance);
2836 spin_unlock_irq(instance->host_lock);
2837
2838 return SUCCESS;
2839}
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
281static int do_abort(struct Scsi_Host *host);
282static 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
291static __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
325static 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
356static 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
370static 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},
384basrs[] = {
385 {BASR_ATN, "ATN"},
386 {BASR_ACK, "ACK"},
387 {0, NULL}
388},
389icrs[] = {
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},
398mrs[] = {
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
418static 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
459static 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
521static 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
541static 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
548static 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
560static 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
577static 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
632static void __init __maybe_unused
633NCR5380_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
678static 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)
700static
701char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length);
702static
703char *lprint_command(unsigned char *cmd, char *pos, char *buffer, int len);
704static
705char *lprint_opcode(int opcode, char *pos, char *buffer, int length);
706
707static 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
776static 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
784static 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
794static 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
817static 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
935static 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
954static 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
1023static 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
1037static 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
1160static 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
1242static 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
1296static 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
1450part2:
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 */
1550failed:
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
1580static 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
1717static 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
1739static 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
1812static 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
2093static 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
2505static 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
2624static 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
2679static 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
2833static 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}