[SCSI] NCR5380 family: convert to accessors & !use_sg cleanup
[linux-2.6.git] / drivers / scsi / NCR5380.c
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@redhat.com)
34  * Fixed up the timer lockups reported so far. Things still suck. Looking 
35  * forward to 2.3 and per device request queues. Then it'll be possible to
36  * SMP thread this beast and improve life no end.
37  
38  * Revision 1.9  1997/7/27      Ronald van Cuijlenborg
39  *                              (ronald.van.cuijlenborg@tip.nl or nutty@dds.nl)
40  * (hopefully) fixed and enhanced USLEEP
41  * added support for DTC3181E card (for Mustek scanner)
42  *
43
44  * Revision 1.8                 Ingmar Baumgart
45  *                              (ingmar@gonzo.schwaben.de)
46  * added support for NCR53C400a card
47  *
48
49  * Revision 1.7  1996/3/2       Ray Van Tassle (rayvt@comm.mot.com)
50  * added proc_info
51  * added support needed for DTC 3180/3280
52  * fixed a couple of bugs
53  *
54
55  * Revision 1.5  1994/01/19  09:14:57  drew
56  * Fixed udelay() hack that was being used on DATAOUT phases
57  * instead of a proper wait for the final handshake.
58  *
59  * Revision 1.4  1994/01/19  06:44:25  drew
60  * *** empty log message ***
61  *
62  * Revision 1.3  1994/01/19  05:24:40  drew
63  * Added support for TCR LAST_BYTE_SENT bit.
64  *
65  * Revision 1.2  1994/01/15  06:14:11  drew
66  * REAL DMA support, bug fixes.
67  *
68  * Revision 1.1  1994/01/15  06:00:54  drew
69  * Initial revision
70  *
71  */
72
73 /*
74  * Further development / testing that should be done : 
75  * 1.  Cleanup the NCR5380_transfer_dma function and DMA operation complete
76  *     code so that everything does the same thing that's done at the 
77  *     end of a pseudo-DMA read operation.
78  *
79  * 2.  Fix REAL_DMA (interrupt driven, polled works fine) -
80  *     basically, transfer size needs to be reduced by one 
81  *     and the last byte read as is done with PSEUDO_DMA.
82  * 
83  * 4.  Test SCSI-II tagged queueing (I have no devices which support 
84  *      tagged queueing)
85  *
86  * 5.  Test linked command handling code after Eric is ready with 
87  *      the high level code.
88  */
89 #include <scsi/scsi_dbg.h>
90 #include <scsi/scsi_transport_spi.h>
91
92 #ifndef NDEBUG
93 #define NDEBUG 0
94 #endif
95 #ifndef NDEBUG_ABORT
96 #define NDEBUG_ABORT 0
97 #endif
98
99 #if (NDEBUG & NDEBUG_LISTS)
100 #define LIST(x,y) {printk("LINE:%d   Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); if ((x)==(y)) udelay(5); }
101 #define REMOVE(w,x,y,z) {printk("LINE:%d   Removing: %p->%p  %p->%p \n", __LINE__, (void*)(w), (void*)(x), (void*)(y), (void*)(z)); if ((x)==(y)) udelay(5); }
102 #else
103 #define LIST(x,y)
104 #define REMOVE(w,x,y,z)
105 #endif
106
107 #ifndef notyet
108 #undef LINKED
109 #undef REAL_DMA
110 #endif
111
112 #ifdef REAL_DMA_POLL
113 #undef READ_OVERRUNS
114 #define READ_OVERRUNS
115 #endif
116
117 #ifdef BOARD_REQUIRES_NO_DELAY
118 #define io_recovery_delay(x)
119 #else
120 #define io_recovery_delay(x)    udelay(x)
121 #endif
122
123 /*
124  * Design
125  *
126  * This is a generic 5380 driver.  To use it on a different platform, 
127  * one simply writes appropriate system specific macros (ie, data
128  * transfer - some PC's will use the I/O bus, 68K's must use 
129  * memory mapped) and drops this file in their 'C' wrapper.
130  *
131  * (Note from hch:  unfortunately it was not enough for the different
132  * m68k folks and instead of improving this driver they copied it
133  * and hacked it up for their needs.  As a consequence they lost
134  * most updates to this driver.  Maybe someone will fix all these
135  * drivers to use a common core one day..)
136  *
137  * As far as command queueing, two queues are maintained for 
138  * each 5380 in the system - commands that haven't been issued yet,
139  * and commands that are currently executing.  This means that an 
140  * unlimited number of commands may be queued, letting 
141  * more commands propagate from the higher driver levels giving higher 
142  * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported, 
143  * allowing multiple commands to propagate all the way to a SCSI-II device 
144  * while a command is already executing.
145  *
146  *
147  * Issues specific to the NCR5380 : 
148  *
149  * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 
150  * piece of hardware that requires you to sit in a loop polling for 
151  * the REQ signal as long as you are connected.  Some devices are 
152  * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 
153  * while doing long seek operations.
154  * 
155  * The workaround for this is to keep track of devices that have
156  * disconnected.  If the device hasn't disconnected, for commands that
157  * should disconnect, we do something like 
158  *
159  * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
160  * 
161  * Some tweaking of N and M needs to be done.  An algorithm based 
162  * on "time to data" would give the best results as long as short time
163  * to datas (ie, on the same track) were considered, however these 
164  * broken devices are the exception rather than the rule and I'd rather
165  * spend my time optimizing for the normal case.
166  *
167  * Architecture :
168  *
169  * At the heart of the design is a coroutine, NCR5380_main,
170  * which is started from a workqueue for each NCR5380 host in the
171  * system.  It attempts to establish I_T_L or I_T_L_Q nexuses by
172  * removing the commands from the issue queue and calling
173  * NCR5380_select() if a nexus is not established. 
174  *
175  * Once a nexus is established, the NCR5380_information_transfer()
176  * phase goes through the various phases as instructed by the target.
177  * if the target goes into MSG IN and sends a DISCONNECT message,
178  * the command structure is placed into the per instance disconnected
179  * queue, and NCR5380_main tries to find more work.  If the target is 
180  * idle for too long, the system will try to sleep.
181  *
182  * If a command has disconnected, eventually an interrupt will trigger,
183  * calling NCR5380_intr()  which will in turn call NCR5380_reselect
184  * to reestablish a nexus.  This will run main if necessary.
185  *
186  * On command termination, the done function will be called as 
187  * appropriate.
188  *
189  * SCSI pointers are maintained in the SCp field of SCSI command 
190  * structures, being initialized after the command is connected
191  * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
192  * Note that in violation of the standard, an implicit SAVE POINTERS operation
193  * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
194  */
195
196 /*
197  * Using this file :
198  * This file a skeleton Linux SCSI driver for the NCR 5380 series
199  * of chips.  To use it, you write an architecture specific functions 
200  * and macros and include this file in your driver.
201  *
202  * These macros control options : 
203  * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be 
204  *      defined.
205  * 
206  * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
207  *      for commands that return with a CHECK CONDITION status. 
208  *
209  * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
210  *      transceivers. 
211  *
212  * DONT_USE_INTR - if defined, never use interrupts, even if we probe or
213  *      override-configure an IRQ.
214  *
215  * LIMIT_TRANSFERSIZE - if defined, limit the pseudo-dma transfers to 512
216  *      bytes at a time.  Since interrupts are disabled by default during
217  *      these transfers, we might need this to give reasonable interrupt
218  *      service time if the transfer size gets too large.
219  *
220  * LINKED - if defined, linked commands are supported.
221  *
222  * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
223  *
224  * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
225  *
226  * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't
227  *      rely on phase mismatch and EOP interrupts to determine end 
228  *      of phase.
229  *
230  * UNSAFE - leave interrupts enabled during pseudo-DMA transfers.  You
231  *          only really want to use this if you're having a problem with
232  *          dropped characters during high speed communications, and even
233  *          then, you're going to be better off twiddling with transfersize
234  *          in the high level code.
235  *
236  * Defaults for these will be provided although the user may want to adjust 
237  * these to allocate CPU resources to the SCSI driver or "real" code.
238  * 
239  * USLEEP_SLEEP - amount of time, in jiffies, to sleep
240  *
241  * USLEEP_POLL - amount of time, in jiffies, to poll
242  *
243  * These macros MUST be defined :
244  * NCR5380_local_declare() - declare any local variables needed for your
245  *      transfer routines.
246  *
247  * NCR5380_setup(instance) - initialize any local variables needed from a given
248  *      instance of the host adapter for NCR5380_{read,write,pread,pwrite}
249  * 
250  * NCR5380_read(register)  - read from the specified register
251  *
252  * NCR5380_write(register, value) - write to the specific register 
253  *
254  * NCR5380_implementation_fields  - additional fields needed for this 
255  *      specific implementation of the NCR5380
256  *
257  * Either real DMA *or* pseudo DMA may be implemented
258  * REAL functions : 
259  * NCR5380_REAL_DMA should be defined if real DMA is to be used.
260  * Note that the DMA setup functions should return the number of bytes 
261  *      that they were able to program the controller for.
262  *
263  * Also note that generic i386/PC versions of these macros are 
264  *      available as NCR5380_i386_dma_write_setup,
265  *      NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
266  *
267  * NCR5380_dma_write_setup(instance, src, count) - initialize
268  * NCR5380_dma_read_setup(instance, dst, count) - initialize
269  * NCR5380_dma_residual(instance); - residual count
270  *
271  * PSEUDO functions :
272  * NCR5380_pwrite(instance, src, count)
273  * NCR5380_pread(instance, dst, count);
274  *
275  * The generic driver is initialized by calling NCR5380_init(instance),
276  * after setting the appropriate host specific fields and ID.  If the 
277  * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
278  * possible) function may be used.
279  */
280
281 static int do_abort(struct Scsi_Host *host);
282 static void do_reset(struct Scsi_Host *host);
283
284 /*
285  *      initialize_SCp          -       init the scsi pointer field
286  *      @cmd: command block to set up
287  *
288  *      Set up the internal fields in the SCSI command.
289  */
290
291 static __inline__ void initialize_SCp(Scsi_Cmnd * cmd)
292 {
293         /* 
294          * Initialize the Scsi Pointer field so that all of the commands in the 
295          * various queues are valid.
296          */
297
298         if (scsi_bufflen(cmd)) {
299                 cmd->SCp.buffer = scsi_sglist(cmd);
300                 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
301                 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
302                 cmd->SCp.this_residual = cmd->SCp.buffer->length;
303         } else {
304                 cmd->SCp.buffer = NULL;
305                 cmd->SCp.buffers_residual = 0;
306                 cmd->SCp.ptr = NULL;
307                 cmd->SCp.this_residual = 0;
308         }
309 }
310
311 /**
312  *      NCR5380_poll_politely   -       wait for NCR5380 status bits
313  *      @instance: controller to poll
314  *      @reg: 5380 register to poll
315  *      @bit: Bitmask to check
316  *      @val: Value required to exit
317  *
318  *      Polls the NCR5380 in a reasonably efficient manner waiting for
319  *      an event to occur, after a short quick poll we begin giving the
320  *      CPU back in non IRQ contexts
321  *
322  *      Returns the value of the register or a negative error code.
323  */
324  
325 static int NCR5380_poll_politely(struct Scsi_Host *instance, int reg, int bit, int val, int t)
326 {
327         NCR5380_local_declare();
328         int n = 500;            /* At about 8uS a cycle for the cpu access */
329         unsigned long end = jiffies + t;
330         int r;
331         
332         NCR5380_setup(instance);
333
334         while( n-- > 0)
335         {
336                 r = NCR5380_read(reg);
337                 if((r & bit) == val)
338                         return 0;
339                 cpu_relax();
340         }
341         
342         /* t time yet ? */
343         while(time_before(jiffies, end))
344         {
345                 r = NCR5380_read(reg);
346                 if((r & bit) == val)
347                         return 0;
348                 if(!in_interrupt())
349                         cond_resched();
350                 else
351                         cpu_relax();
352         }
353         return -ETIMEDOUT;
354 }
355
356 static struct {
357         unsigned char value;
358         const char *name;
359 } phases[] __maybe_unused = {
360         {PHASE_DATAOUT, "DATAOUT"}, 
361         {PHASE_DATAIN, "DATAIN"}, 
362         {PHASE_CMDOUT, "CMDOUT"}, 
363         {PHASE_STATIN, "STATIN"}, 
364         {PHASE_MSGOUT, "MSGOUT"}, 
365         {PHASE_MSGIN, "MSGIN"}, 
366         {PHASE_UNKNOWN, "UNKNOWN"}
367 };
368
369 #if NDEBUG
370 static struct {
371         unsigned char mask;
372         const char *name;
373 } signals[] = { 
374         {SR_DBP, "PARITY"}, 
375         {SR_RST, "RST"}, 
376         {SR_BSY, "BSY"}, 
377         {SR_REQ, "REQ"}, 
378         {SR_MSG, "MSG"}, 
379         {SR_CD, "CD"}, 
380         {SR_IO, "IO"}, 
381         {SR_SEL, "SEL"}, 
382         {0, NULL}
383 }, 
384 basrs[] = {
385         {BASR_ATN, "ATN"}, 
386         {BASR_ACK, "ACK"}, 
387         {0, NULL}
388 }, 
389 icrs[] = { 
390         {ICR_ASSERT_RST, "ASSERT RST"}, 
391         {ICR_ASSERT_ACK, "ASSERT ACK"}, 
392         {ICR_ASSERT_BSY, "ASSERT BSY"}, 
393         {ICR_ASSERT_SEL, "ASSERT SEL"}, 
394         {ICR_ASSERT_ATN, "ASSERT ATN"}, 
395         {ICR_ASSERT_DATA, "ASSERT DATA"}, 
396         {0, NULL}
397 }, 
398 mrs[] = { 
399         {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, 
400         {MR_TARGET, "MODE TARGET"}, 
401         {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, 
402         {MR_ENABLE_PAR_INTR, "MODE PARITY INTR"}, 
403         {MR_MONITOR_BSY, "MODE MONITOR BSY"}, 
404         {MR_DMA_MODE, "MODE DMA"}, 
405         {MR_ARBITRATE, "MODE ARBITRATION"}, 
406         {0, NULL}
407 };
408
409 /**
410  *      NCR5380_print   -       print scsi bus signals
411  *      @instance:      adapter state to dump
412  *
413  *      Print the SCSI bus signals for debugging purposes
414  *
415  *      Locks: caller holds hostdata lock (not essential)
416  */
417
418 static void NCR5380_print(struct Scsi_Host *instance)
419 {
420         NCR5380_local_declare();
421         unsigned char status, data, basr, mr, icr, i;
422         NCR5380_setup(instance);
423
424         data = NCR5380_read(CURRENT_SCSI_DATA_REG);
425         status = NCR5380_read(STATUS_REG);
426         mr = NCR5380_read(MODE_REG);
427         icr = NCR5380_read(INITIATOR_COMMAND_REG);
428         basr = NCR5380_read(BUS_AND_STATUS_REG);
429
430         printk("STATUS_REG: %02x ", status);
431         for (i = 0; signals[i].mask; ++i)
432                 if (status & signals[i].mask)
433                         printk(",%s", signals[i].name);
434         printk("\nBASR: %02x ", basr);
435         for (i = 0; basrs[i].mask; ++i)
436                 if (basr & basrs[i].mask)
437                         printk(",%s", basrs[i].name);
438         printk("\nICR: %02x ", icr);
439         for (i = 0; icrs[i].mask; ++i)
440                 if (icr & icrs[i].mask)
441                         printk(",%s", icrs[i].name);
442         printk("\nMODE: %02x ", mr);
443         for (i = 0; mrs[i].mask; ++i)
444                 if (mr & mrs[i].mask)
445                         printk(",%s", mrs[i].name);
446         printk("\n");
447 }
448
449
450 /* 
451  *      NCR5380_print_phase     -       show SCSI phase
452  *      @instance: adapter to dump
453  *
454  *      Print the current SCSI phase for debugging purposes
455  *
456  *      Locks: none
457  */
458
459 static void NCR5380_print_phase(struct Scsi_Host *instance)
460 {
461         NCR5380_local_declare();
462         unsigned char status;
463         int i;
464         NCR5380_setup(instance);
465
466         status = NCR5380_read(STATUS_REG);
467         if (!(status & SR_REQ))
468                 printk("scsi%d : REQ not asserted, phase unknown.\n", instance->host_no);
469         else {
470                 for (i = 0; (phases[i].value != PHASE_UNKNOWN) && (phases[i].value != (status & PHASE_MASK)); ++i);
471                 printk("scsi%d : phase %s\n", instance->host_no, phases[i].name);
472         }
473 }
474 #endif
475
476 /*
477  * These need tweaking, and would probably work best as per-device 
478  * flags initialized differently for disk, tape, cd, etc devices.
479  * People with broken devices are free to experiment as to what gives
480  * the best results for them.
481  *
482  * USLEEP_SLEEP should be a minimum seek time.
483  *
484  * USLEEP_POLL should be a maximum rotational latency.
485  */
486 #ifndef USLEEP_SLEEP
487 /* 20 ms (reasonable hard disk speed) */
488 #define USLEEP_SLEEP (20*HZ/1000)
489 #endif
490 /* 300 RPM (floppy speed) */
491 #ifndef USLEEP_POLL
492 #define USLEEP_POLL (200*HZ/1000)
493 #endif
494 #ifndef USLEEP_WAITLONG
495 /* RvC: (reasonable time to wait on select error) */
496 #define USLEEP_WAITLONG USLEEP_SLEEP
497 #endif
498
499 /* 
500  * Function : int should_disconnect (unsigned char cmd)
501  *
502  * Purpose : decide whether a command would normally disconnect or 
503  *      not, since if it won't disconnect we should go to sleep.
504  *
505  * Input : cmd - opcode of SCSI command
506  *
507  * Returns : DISCONNECT_LONG if we should disconnect for a really long 
508  *      time (ie always, sleep, look for REQ active, sleep), 
509  *      DISCONNECT_TIME_TO_DATA if we would only disconnect for a normal
510  *      time-to-data delay, DISCONNECT_NONE if this command would return
511  *      immediately.
512  *
513  *      Future sleep algorithms based on time to data can exploit 
514  *      something like this so they can differentiate between "normal" 
515  *      (ie, read, write, seek) and unusual commands (ie, * format).
516  *
517  * Note : We don't deal with commands that handle an immediate disconnect,
518  *        
519  */
520
521 static int should_disconnect(unsigned char cmd)
522 {
523         switch (cmd) {
524         case READ_6:
525         case WRITE_6:
526         case SEEK_6:
527         case READ_10:
528         case WRITE_10:
529         case SEEK_10:
530                 return DISCONNECT_TIME_TO_DATA;
531         case FORMAT_UNIT:
532         case SEARCH_HIGH:
533         case SEARCH_LOW:
534         case SEARCH_EQUAL:
535                 return DISCONNECT_LONG;
536         default:
537                 return DISCONNECT_NONE;
538         }
539 }
540
541 static void NCR5380_set_timer(struct NCR5380_hostdata *hostdata, unsigned long timeout)
542 {
543         hostdata->time_expires = jiffies + timeout;
544         schedule_delayed_work(&hostdata->coroutine, timeout);
545 }
546
547
548 static int probe_irq __initdata = 0;
549
550 /**
551  *      probe_intr      -       helper for IRQ autoprobe
552  *      @irq: interrupt number
553  *      @dev_id: unused
554  *      @regs: unused
555  *
556  *      Set a flag to indicate the IRQ in question was received. This is
557  *      used by the IRQ probe code.
558  */
559  
560 static irqreturn_t __init probe_intr(int irq, void *dev_id)
561 {
562         probe_irq = irq;
563         return IRQ_HANDLED;
564 }
565
566 /**
567  *      NCR5380_probe_irq       -       find the IRQ of an NCR5380
568  *      @instance: NCR5380 controller
569  *      @possible: bitmask of ISA IRQ lines
570  *
571  *      Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ
572  *      and then looking to see what interrupt actually turned up.
573  *
574  *      Locks: none, irqs must be enabled on entry
575  */
576
577 static int __init __maybe_unused NCR5380_probe_irq(struct Scsi_Host *instance,
578                                                 int possible)
579 {
580         NCR5380_local_declare();
581         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
582         unsigned long timeout;
583         int trying_irqs, i, mask;
584         NCR5380_setup(instance);
585
586         for (trying_irqs = i = 0, mask = 1; i < 16; ++i, mask <<= 1)
587                 if ((mask & possible) && (request_irq(i, &probe_intr, IRQF_DISABLED, "NCR-probe", NULL) == 0))
588                         trying_irqs |= mask;
589
590         timeout = jiffies + (250 * HZ / 1000);
591         probe_irq = SCSI_IRQ_NONE;
592
593         /*
594          * A interrupt is triggered whenever BSY = false, SEL = true
595          * and a bit set in the SELECT_ENABLE_REG is asserted on the 
596          * SCSI bus.
597          *
598          * Note that the bus is only driven when the phase control signals
599          * (I/O, C/D, and MSG) match those in the TCR, so we must reset that
600          * to zero.
601          */
602
603         NCR5380_write(TARGET_COMMAND_REG, 0);
604         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
605         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
606         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL);
607
608         while (probe_irq == SCSI_IRQ_NONE && time_before(jiffies, timeout))
609                 schedule_timeout_uninterruptible(1);
610         
611         NCR5380_write(SELECT_ENABLE_REG, 0);
612         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
613
614         for (i = 0, mask = 1; i < 16; ++i, mask <<= 1)
615                 if (trying_irqs & mask)
616                         free_irq(i, NULL);
617
618         return probe_irq;
619 }
620
621 /**
622  *      NCR58380_print_options  -       show options
623  *      @instance: unused for now
624  *
625  *      Called by probe code indicating the NCR5380 driver options that 
626  *      were selected. At some point this will switch to runtime options
627  *      read from the adapter in question
628  *
629  *      Locks: none
630  */
631
632 static void __init __maybe_unused
633 NCR5380_print_options(struct Scsi_Host *instance)
634 {
635         printk(" generic options"
636 #ifdef AUTOPROBE_IRQ
637                " AUTOPROBE_IRQ"
638 #endif
639 #ifdef AUTOSENSE
640                " AUTOSENSE"
641 #endif
642 #ifdef DIFFERENTIAL
643                " DIFFERENTIAL"
644 #endif
645 #ifdef REAL_DMA
646                " REAL DMA"
647 #endif
648 #ifdef REAL_DMA_POLL
649                " REAL DMA POLL"
650 #endif
651 #ifdef PARITY
652                " PARITY"
653 #endif
654 #ifdef PSEUDO_DMA
655                " PSEUDO DMA"
656 #endif
657 #ifdef UNSAFE
658                " UNSAFE "
659 #endif
660             );
661         printk(" USLEEP, USLEEP_POLL=%d USLEEP_SLEEP=%d", USLEEP_POLL, USLEEP_SLEEP);
662         printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
663         if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) {
664                 printk(" ncr53c400 release=%d", NCR53C400_PUBLIC_RELEASE);
665         }
666 }
667
668 /**
669  *      NCR5380_print_status    -       dump controller info
670  *      @instance: controller to dump
671  *
672  *      Print commands in the various queues, called from NCR5380_abort 
673  *      and NCR5380_debug to aid debugging.
674  *
675  *      Locks: called functions disable irqs
676  */
677
678 static void NCR5380_print_status(struct Scsi_Host *instance)
679 {
680         NCR5380_dprint(NDEBUG_ANY, instance);
681         NCR5380_dprint_phase(NDEBUG_ANY, instance);
682 }
683
684 /******************************************/
685 /*
686  * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
687  *
688  * *buffer: I/O buffer
689  * **start: if inout == FALSE pointer into buffer where user read should start
690  * offset: current offset
691  * length: length of buffer
692  * hostno: Scsi_Host host_no
693  * inout: TRUE - user is writing; FALSE - user is reading
694  *
695  * Return the number of bytes read from or written
696  */
697
698 #undef SPRINTF
699 #define SPRINTF(args...) do { if(pos < buffer + length-80) pos += sprintf(pos, ## args); } while(0)
700 static
701 char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length);
702 static
703 char *lprint_command(unsigned char *cmd, char *pos, char *buffer, int len);
704 static
705 char *lprint_opcode(int opcode, char *pos, char *buffer, int length);
706
707 static int __maybe_unused NCR5380_proc_info(struct Scsi_Host *instance,
708         char *buffer, char **start, off_t offset, int length, int inout)
709 {
710         char *pos = buffer;
711         struct NCR5380_hostdata *hostdata;
712         Scsi_Cmnd *ptr;
713
714         hostdata = (struct NCR5380_hostdata *) instance->hostdata;
715
716         if (inout) {            /* Has data been written to the file ? */
717 #ifdef DTC_PUBLIC_RELEASE
718                 dtc_wmaxi = dtc_maxi = 0;
719 #endif
720 #ifdef PAS16_PUBLIC_RELEASE
721                 pas_wmaxi = pas_maxi = 0;
722 #endif
723                 return (-ENOSYS);       /* Currently this is a no-op */
724         }
725         SPRINTF("NCR5380 core release=%d.   ", NCR5380_PUBLIC_RELEASE);
726         if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400)
727                 SPRINTF("ncr53c400 release=%d.  ", NCR53C400_PUBLIC_RELEASE);
728 #ifdef DTC_PUBLIC_RELEASE
729         SPRINTF("DTC 3180/3280 release %d", DTC_PUBLIC_RELEASE);
730 #endif
731 #ifdef T128_PUBLIC_RELEASE
732         SPRINTF("T128 release %d", T128_PUBLIC_RELEASE);
733 #endif
734 #ifdef GENERIC_NCR5380_PUBLIC_RELEASE
735         SPRINTF("Generic5380 release %d", GENERIC_NCR5380_PUBLIC_RELEASE);
736 #endif
737 #ifdef PAS16_PUBLIC_RELEASE
738         SPRINTF("PAS16 release=%d", PAS16_PUBLIC_RELEASE);
739 #endif
740
741         SPRINTF("\nBase Addr: 0x%05lX    ", (long) instance->base);
742         SPRINTF("io_port: %04x      ", (int) instance->io_port);
743         if (instance->irq == SCSI_IRQ_NONE)
744                 SPRINTF("IRQ: None.\n");
745         else
746                 SPRINTF("IRQ: %d.\n", instance->irq);
747
748 #ifdef DTC_PUBLIC_RELEASE
749         SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", dtc_wmaxi, dtc_maxi);
750 #endif
751 #ifdef PAS16_PUBLIC_RELEASE
752         SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", pas_wmaxi, pas_maxi);
753 #endif
754         spin_lock_irq(instance->host_lock);
755         if (!hostdata->connected)
756                 SPRINTF("scsi%d: no currently connected command\n", instance->host_no);
757         else
758                 pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, pos, buffer, length);
759         SPRINTF("scsi%d: issue_queue\n", instance->host_no);
760         for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
761                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
762
763         SPRINTF("scsi%d: disconnected_queue\n", instance->host_no);
764         for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
765                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
766         spin_unlock_irq(instance->host_lock);
767         
768         *start = buffer;
769         if (pos - buffer < offset)
770                 return 0;
771         else if (pos - buffer - offset < length)
772                 return pos - buffer - offset;
773         return length;
774 }
775
776 static char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length)
777 {
778         SPRINTF("scsi%d : destination target %d, lun %d\n", cmd->device->host->host_no, cmd->device->id, cmd->device->lun);
779         SPRINTF("        command = ");
780         pos = lprint_command(cmd->cmnd, pos, buffer, length);
781         return (pos);
782 }
783
784 static char *lprint_command(unsigned char *command, char *pos, char *buffer, int length)
785 {
786         int i, s;
787         pos = lprint_opcode(command[0], pos, buffer, length);
788         for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
789                 SPRINTF("%02x ", command[i]);
790         SPRINTF("\n");
791         return (pos);
792 }
793
794 static char *lprint_opcode(int opcode, char *pos, char *buffer, int length)
795 {
796         SPRINTF("%2d (0x%02x)", opcode, opcode);
797         return (pos);
798 }
799
800
801 /**
802  *      NCR5380_init    -       initialise an NCR5380
803  *      @instance: adapter to configure
804  *      @flags: control flags
805  *
806  *      Initializes *instance and corresponding 5380 chip,
807  *      with flags OR'd into the initial flags value.
808  *
809  *      Notes : I assume that the host, hostno, and id bits have been
810  *      set correctly.  I don't care about the irq and other fields. 
811  *
812  *      Returns 0 for success
813  *
814  *      Locks: interrupts must be enabled when we are called 
815  */
816
817 static int __devinit NCR5380_init(struct Scsi_Host *instance, int flags)
818 {
819         NCR5380_local_declare();
820         int i, pass;
821         unsigned long timeout;
822         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
823
824         if(in_interrupt())
825                 printk(KERN_ERR "NCR5380_init called with interrupts off!\n");
826         /* 
827          * On NCR53C400 boards, NCR5380 registers are mapped 8 past 
828          * the base address.
829          */
830
831 #ifdef NCR53C400
832         if (flags & FLAG_NCR53C400)
833                 instance->NCR5380_instance_name += NCR53C400_address_adjust;
834 #endif
835
836         NCR5380_setup(instance);
837
838         hostdata->aborted = 0;
839         hostdata->id_mask = 1 << instance->this_id;
840         for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
841                 if (i > hostdata->id_mask)
842                         hostdata->id_higher_mask |= i;
843         for (i = 0; i < 8; ++i)
844                 hostdata->busy[i] = 0;
845 #ifdef REAL_DMA
846         hostdata->dmalen = 0;
847 #endif
848         hostdata->targets_present = 0;
849         hostdata->connected = NULL;
850         hostdata->issue_queue = NULL;
851         hostdata->disconnected_queue = NULL;
852         
853         INIT_DELAYED_WORK(&hostdata->coroutine, NCR5380_main);
854         
855 #ifdef NCR5380_STATS
856         for (i = 0; i < 8; ++i) {
857                 hostdata->time_read[i] = 0;
858                 hostdata->time_write[i] = 0;
859                 hostdata->bytes_read[i] = 0;
860                 hostdata->bytes_write[i] = 0;
861         }
862         hostdata->timebase = 0;
863         hostdata->pendingw = 0;
864         hostdata->pendingr = 0;
865 #endif
866
867         /* The CHECK code seems to break the 53C400. Will check it later maybe */
868         if (flags & FLAG_NCR53C400)
869                 hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags;
870         else
871                 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags;
872
873         hostdata->host = instance;
874         hostdata->time_expires = 0;
875
876 #ifndef AUTOSENSE
877         if ((instance->cmd_per_lun > 1) || instance->can_queue > 1)
878                     printk(KERN_WARNING "scsi%d : WARNING : support for multiple outstanding commands enabled\n" "         without AUTOSENSE option, contingent allegiance conditions may\n"
879                            "         be incorrectly cleared.\n", instance->host_no);
880 #endif                          /* def AUTOSENSE */
881
882         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
883         NCR5380_write(MODE_REG, MR_BASE);
884         NCR5380_write(TARGET_COMMAND_REG, 0);
885         NCR5380_write(SELECT_ENABLE_REG, 0);
886
887 #ifdef NCR53C400
888         if (hostdata->flags & FLAG_NCR53C400) {
889                 NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE);
890         }
891 #endif
892
893         /* 
894          * Detect and correct bus wedge problems.
895          *
896          * If the system crashed, it may have crashed in a state 
897          * where a SCSI command was still executing, and the 
898          * SCSI bus is not in a BUS FREE STATE.
899          *
900          * If this is the case, we'll try to abort the currently
901          * established nexus which we know nothing about, and that
902          * failing, do a hard reset of the SCSI bus 
903          */
904
905         for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
906                 switch (pass) {
907                 case 1:
908                 case 3:
909                 case 5:
910                         printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no);
911                         timeout = jiffies + 5 * HZ;
912                         NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ);
913                         break;
914                 case 2:
915                         printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no);
916                         do_abort(instance);
917                         break;
918                 case 4:
919                         printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no);
920                         do_reset(instance);
921                         break;
922                 case 6:
923                         printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no);
924                         return -ENXIO;
925                 }
926         }
927         return 0;
928 }
929
930 /**
931  *      NCR5380_exit    -       remove an NCR5380
932  *      @instance: adapter to remove
933  */
934
935 static void __devexit NCR5380_exit(struct Scsi_Host *instance)
936 {
937         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
938
939         cancel_delayed_work(&hostdata->coroutine);
940         flush_scheduled_work();
941 }
942
943 /**
944  *      NCR5380_queue_command           -       queue a command
945  *      @cmd: SCSI command
946  *      @done: completion handler
947  *
948  *      cmd is added to the per instance issue_queue, with minor 
949  *      twiddling done to the host specific fields of cmd.  If the 
950  *      main coroutine is not running, it is restarted.
951  *
952  *      Locks: host lock taken by caller
953  */
954
955 static int NCR5380_queue_command(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *)) 
956 {
957         struct Scsi_Host *instance = cmd->device->host;
958         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
959         Scsi_Cmnd *tmp;
960
961 #if (NDEBUG & NDEBUG_NO_WRITE)
962         switch (cmd->cmnd[0]) {
963         case WRITE_6:
964         case WRITE_10:
965                 printk("scsi%d : WRITE attempted with NO_WRITE debugging flag set\n", instance->host_no);
966                 cmd->result = (DID_ERROR << 16);
967                 done(cmd);
968                 return 0;
969         }
970 #endif                          /* (NDEBUG & NDEBUG_NO_WRITE) */
971
972 #ifdef NCR5380_STATS
973         switch (cmd->cmnd[0]) {
974                 case WRITE:
975                 case WRITE_6:
976                 case WRITE_10:
977                         hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
978                         hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);
979                         hostdata->pendingw++;
980                         break;
981                 case READ:
982                 case READ_6:
983                 case READ_10:
984                         hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
985                         hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);
986                         hostdata->pendingr++;
987                         break;
988         }
989 #endif
990
991         /* 
992          * We use the host_scribble field as a pointer to the next command  
993          * in a queue 
994          */
995
996         cmd->host_scribble = NULL;
997         cmd->scsi_done = done;
998         cmd->result = 0;
999
1000         /* 
1001          * Insert the cmd into the issue queue. Note that REQUEST SENSE 
1002          * commands are added to the head of the queue since any command will
1003          * clear the contingent allegiance condition that exists and the 
1004          * sense data is only guaranteed to be valid while the condition exists.
1005          */
1006
1007         if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
1008                 LIST(cmd, hostdata->issue_queue);
1009                 cmd->host_scribble = (unsigned char *) hostdata->issue_queue;
1010                 hostdata->issue_queue = cmd;
1011         } else {
1012                 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp->host_scribble; tmp = (Scsi_Cmnd *) tmp->host_scribble);
1013                 LIST(cmd, tmp);
1014                 tmp->host_scribble = (unsigned char *) cmd;
1015         }
1016         dprintk(NDEBUG_QUEUES, ("scsi%d : command added to %s of queue\n", instance->host_no, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"));
1017
1018         /* Run the coroutine if it isn't already running. */
1019         /* Kick off command processing */
1020         schedule_delayed_work(&hostdata->coroutine, 0);
1021         return 0;
1022 }
1023
1024
1025 /**
1026  *      NCR5380_main    -       NCR state machines
1027  *
1028  *      NCR5380_main is a coroutine that runs as long as more work can 
1029  *      be done on the NCR5380 host adapters in a system.  Both 
1030  *      NCR5380_queue_command() and NCR5380_intr() will try to start it 
1031  *      in case it is not running.
1032  * 
1033  *      Locks: called as its own thread with no locks held. Takes the
1034  *      host lock and called routines may take the isa dma lock.
1035  */
1036
1037 static void NCR5380_main(struct work_struct *work)
1038 {
1039         struct NCR5380_hostdata *hostdata =
1040                 container_of(work, struct NCR5380_hostdata, coroutine.work);
1041         struct Scsi_Host *instance = hostdata->host;
1042         Scsi_Cmnd *tmp, *prev;
1043         int done;
1044         
1045         spin_lock_irq(instance->host_lock);
1046         do {
1047                 /* Lock held here */
1048                 done = 1;
1049                 if (!hostdata->connected && !hostdata->selecting) {
1050                         dprintk(NDEBUG_MAIN, ("scsi%d : not connected\n", instance->host_no));
1051                         /*
1052                          * Search through the issue_queue for a command destined
1053                          * for a target that's not busy.
1054                          */
1055                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble) 
1056                         {
1057                                 if (prev != tmp)
1058                                         dprintk(NDEBUG_LISTS, ("MAIN tmp=%p   target=%d   busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun));
1059                                 /*  When we find one, remove it from the issue queue. */
1060                                 if (!(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))) {
1061                                         if (prev) {
1062                                                 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
1063                                                 prev->host_scribble = tmp->host_scribble;
1064                                         } else {
1065                                                 REMOVE(-1, hostdata->issue_queue, tmp, tmp->host_scribble);
1066                                                 hostdata->issue_queue = (Scsi_Cmnd *) tmp->host_scribble;
1067                                         }
1068                                         tmp->host_scribble = NULL;
1069
1070                                         /* 
1071                                          * Attempt to establish an I_T_L nexus here. 
1072                                          * On success, instance->hostdata->connected is set.
1073                                          * On failure, we must add the command back to the
1074                                          *   issue queue so we can keep trying. 
1075                                          */
1076                                         dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main() : command for target %d lun %d removed from issue_queue\n", instance->host_no, tmp->target, tmp->lun));
1077         
1078                                         /*
1079                                          * A successful selection is defined as one that 
1080                                          * leaves us with the command connected and 
1081                                          * in hostdata->connected, OR has terminated the
1082                                          * command.
1083                                          *
1084                                          * With successful commands, we fall through
1085                                          * and see if we can do an information transfer,
1086                                          * with failures we will restart.
1087                                          */
1088                                         hostdata->selecting = NULL;
1089                                         /* RvC: have to preset this to indicate a new command is being performed */
1090
1091                                         if (!NCR5380_select(instance, tmp,
1092                                                             /* 
1093                                                              * REQUEST SENSE commands are issued without tagged
1094                                                              * queueing, even on SCSI-II devices because the 
1095                                                              * contingent allegiance condition exists for the 
1096                                                              * entire unit.
1097                                                              */
1098                                                             (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1099                                                 break;
1100                                         } else {
1101                                                 LIST(tmp, hostdata->issue_queue);
1102                                                 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1103                                                 hostdata->issue_queue = tmp;
1104                                                 done = 0;
1105                                                 dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main(): select() failed, returned to issue_queue\n", instance->host_no));
1106                                         }
1107                                         /* lock held here still */
1108                                 }       /* if target/lun is not busy */
1109                         }       /* for */
1110                         /* exited locked */
1111                 }       /* if (!hostdata->connected) */
1112                 if (hostdata->selecting) {
1113                         tmp = (Scsi_Cmnd *) hostdata->selecting;
1114                         /* Selection will drop and retake the lock */
1115                         if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1116                                 /* Ok ?? */
1117                         } else {
1118                                 /* RvC: device failed, so we wait a long time
1119                                    this is needed for Mustek scanners, that
1120                                    do not respond to commands immediately
1121                                    after a scan */
1122                                 printk(KERN_DEBUG "scsi%d: device %d did not respond in time\n", instance->host_no, tmp->device->id);
1123                                 LIST(tmp, hostdata->issue_queue);
1124                                 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1125                                 hostdata->issue_queue = tmp;
1126                                 NCR5380_set_timer(hostdata, USLEEP_WAITLONG);
1127                         }
1128                 }       /* if hostdata->selecting */
1129                 if (hostdata->connected
1130 #ifdef REAL_DMA
1131                     && !hostdata->dmalen
1132 #endif
1133                     && (!hostdata->time_expires || time_before_eq(hostdata->time_expires, jiffies))
1134                     ) {
1135                         dprintk(NDEBUG_MAIN, ("scsi%d : main() : performing information transfer\n", instance->host_no));
1136                         NCR5380_information_transfer(instance);
1137                         dprintk(NDEBUG_MAIN, ("scsi%d : main() : done set false\n", instance->host_no));
1138                         done = 0;
1139                 } else
1140                         break;
1141         } while (!done);
1142         
1143         spin_unlock_irq(instance->host_lock);
1144 }
1145
1146 #ifndef DONT_USE_INTR
1147
1148 /**
1149  *      NCR5380_intr    -       generic NCR5380 irq handler
1150  *      @irq: interrupt number
1151  *      @dev_id: device info
1152  *
1153  *      Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1154  *      from the disconnected queue, and restarting NCR5380_main() 
1155  *      as required.
1156  *
1157  *      Locks: takes the needed instance locks
1158  */
1159
1160 static irqreturn_t NCR5380_intr(int irq, void *dev_id) 
1161 {
1162         NCR5380_local_declare();
1163         struct Scsi_Host *instance = (struct Scsi_Host *)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", irq));
1170
1171         do {
1172                 done = 1;
1173                 spin_lock_irqsave(instance->host_lock, flags);
1174                 /* Look for pending interrupts */
1175                 NCR5380_setup(instance);
1176                 basr = NCR5380_read(BUS_AND_STATUS_REG);
1177                 /* XXX dispatch to appropriate routine if found and done=0 */
1178                 if (basr & BASR_IRQ) {
1179                         NCR5380_dprint(NDEBUG_INTR, instance);
1180                         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1181                                 done = 0;
1182                                 dprintk(NDEBUG_INTR, ("scsi%d : SEL interrupt\n", instance->host_no));
1183                                 NCR5380_reselect(instance);
1184                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1185                         } else if (basr & BASR_PARITY_ERROR) {
1186                                 dprintk(NDEBUG_INTR, ("scsi%d : PARITY interrupt\n", instance->host_no));
1187                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1188                         } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1189                                 dprintk(NDEBUG_INTR, ("scsi%d : RESET interrupt\n", instance->host_no));
1190                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1191                         } else {
1192 #if defined(REAL_DMA)
1193                                 /*
1194                                  * We should only get PHASE MISMATCH and EOP interrupts
1195                                  * if we have DMA enabled, so do a sanity check based on
1196                                  * the current setting of the MODE register.
1197                                  */
1198
1199                                 if ((NCR5380_read(MODE_REG) & MR_DMA) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) {
1200                                         int transfered;
1201
1202                                         if (!hostdata->connected)
1203                                                 panic("scsi%d : received end of DMA interrupt with no connected cmd\n", instance->hostno);
1204
1205                                         transfered = (hostdata->dmalen - NCR5380_dma_residual(instance));
1206                                         hostdata->connected->SCp.this_residual -= transferred;
1207                                         hostdata->connected->SCp.ptr += transferred;
1208                                         hostdata->dmalen = 0;
1209
1210                                         (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1211                                                         
1212                                         /* FIXME: we need to poll briefly then defer a workqueue task ! */
1213                                         NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2*HZ);
1214
1215                                         NCR5380_write(MODE_REG, MR_BASE);
1216                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1217                                 }
1218 #else
1219                                 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)));
1220                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1221 #endif
1222                         }
1223                 }       /* if BASR_IRQ */
1224                 spin_unlock_irqrestore(instance->host_lock, flags);
1225                 if(!done)
1226                         schedule_delayed_work(&hostdata->coroutine, 0);
1227         } while (!done);
1228         return IRQ_HANDLED;
1229 }
1230
1231 #endif 
1232
1233 /**
1234  *      collect_stats           -       collect stats on a scsi command
1235  *      @hostdata: adapter 
1236  *      @cmd: command being issued
1237  *
1238  *      Update the statistical data by parsing the command in question
1239  */
1240  
1241 static void collect_stats(struct NCR5380_hostdata *hostdata, Scsi_Cmnd * cmd) 
1242 {
1243 #ifdef NCR5380_STATS
1244         switch (cmd->cmnd[0]) {
1245         case WRITE:
1246         case WRITE_6:
1247         case WRITE_10:
1248                 hostdata->time_write[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1249                 hostdata->pendingw--;
1250                 break;
1251         case READ:
1252         case READ_6:
1253         case READ_10:
1254                 hostdata->time_read[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1255                 hostdata->pendingr--;
1256                 break;
1257         }
1258 #endif
1259 }
1260
1261
1262 /* 
1263  * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, 
1264  *      int tag);
1265  *
1266  * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1267  *      including ARBITRATION, SELECTION, and initial message out for 
1268  *      IDENTIFY and queue messages. 
1269  *
1270  * Inputs : instance - instantiation of the 5380 driver on which this 
1271  *      target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for 
1272  *      new tag, TAG_NONE for untagged queueing, otherwise set to the tag for 
1273  *      the command that is presently connected.
1274  * 
1275  * Returns : -1 if selection could not execute for some reason,
1276  *      0 if selection succeeded or failed because the target 
1277  *      did not respond.
1278  *
1279  * Side effects : 
1280  *      If bus busy, arbitration failed, etc, NCR5380_select() will exit 
1281  *              with registers as they should have been on entry - ie
1282  *              SELECT_ENABLE will be set appropriately, the NCR5380
1283  *              will cease to drive any SCSI bus signals.
1284  *
1285  *      If successful : I_T_L or I_T_L_Q nexus will be established, 
1286  *              instance->connected will be set to cmd.  
1287  *              SELECT interrupt will be disabled.
1288  *
1289  *      If failed (no target) : cmd->scsi_done() will be called, and the 
1290  *              cmd->result host byte set to DID_BAD_TARGET.
1291  *
1292  *      Locks: caller holds hostdata lock in IRQ mode
1293  */
1294  
1295 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag) 
1296 {
1297         NCR5380_local_declare();
1298         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1299         unsigned char tmp[3], phase;
1300         unsigned char *data;
1301         int len;
1302         unsigned long timeout;
1303         unsigned char value;
1304         int err;
1305         NCR5380_setup(instance);
1306
1307         if (hostdata->selecting)
1308                 goto part2;
1309
1310         hostdata->restart_select = 0;
1311
1312         NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1313         dprintk(NDEBUG_ARBITRATION, ("scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id));
1314
1315         /* 
1316          * Set the phase bits to 0, otherwise the NCR5380 won't drive the 
1317          * data bus during SELECTION.
1318          */
1319
1320         NCR5380_write(TARGET_COMMAND_REG, 0);
1321
1322         /* 
1323          * Start arbitration.
1324          */
1325
1326         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1327         NCR5380_write(MODE_REG, MR_ARBITRATE);
1328
1329
1330         /* We can be relaxed here, interrupts are on, we are
1331            in workqueue context, the birds are singing in the trees */
1332         spin_unlock_irq(instance->host_lock);
1333         err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ);
1334         spin_lock_irq(instance->host_lock);
1335         if (err < 0) {
1336                 printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__);
1337                 NCR5380_write(MODE_REG, MR_BASE);
1338                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1339                 goto failed;
1340         }
1341
1342         dprintk(NDEBUG_ARBITRATION, ("scsi%d : arbitration complete\n", instance->host_no));
1343
1344         /* 
1345          * The arbitration delay is 2.2us, but this is a minimum and there is 
1346          * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1347          * the integral nature of udelay().
1348          *
1349          */
1350
1351         udelay(3);
1352
1353         /* Check for lost arbitration */
1354         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)) {
1355                 NCR5380_write(MODE_REG, MR_BASE);
1356                 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no));
1357                 goto failed;
1358         }
1359         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL);
1360
1361         if (!(hostdata->flags & FLAG_DTC3181E) &&
1362             /* RvC: DTC3181E has some trouble with this
1363              *      so we simply removed it. Seems to work with
1364              *      only Mustek scanner attached
1365              */
1366             (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1367                 NCR5380_write(MODE_REG, MR_BASE);
1368                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1369                 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no));
1370                 goto failed;
1371         }
1372         /* 
1373          * Again, bus clear + bus settle time is 1.2us, however, this is 
1374          * a minimum so we'll udelay ceil(1.2)
1375          */
1376
1377         udelay(2);
1378
1379         dprintk(NDEBUG_ARBITRATION, ("scsi%d : won arbitration\n", instance->host_no));
1380
1381         /* 
1382          * Now that we have won arbitration, start Selection process, asserting 
1383          * the host and target ID's on the SCSI bus.
1384          */
1385
1386         NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << scmd_id(cmd))));
1387
1388         /* 
1389          * Raise ATN while SEL is true before BSY goes false from arbitration,
1390          * since this is the only way to guarantee that we'll get a MESSAGE OUT
1391          * phase immediately after selection.
1392          */
1393
1394         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1395         NCR5380_write(MODE_REG, MR_BASE);
1396
1397         /* 
1398          * Reselect interrupts must be turned off prior to the dropping of BSY,
1399          * otherwise we will trigger an interrupt.
1400          */
1401         NCR5380_write(SELECT_ENABLE_REG, 0);
1402
1403         /*
1404          * The initiator shall then wait at least two deskew delays and release 
1405          * the BSY signal.
1406          */
1407         udelay(1);              /* wingel -- wait two bus deskew delay >2*45ns */
1408
1409         /* Reset BSY */
1410         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1411
1412         /* 
1413          * Something weird happens when we cease to drive BSY - looks
1414          * like the board/chip is letting us do another read before the 
1415          * appropriate propagation delay has expired, and we're confusing
1416          * a BSY signal from ourselves as the target's response to SELECTION.
1417          *
1418          * A small delay (the 'C++' frontend breaks the pipeline with an
1419          * unnecessary jump, making it work on my 386-33/Trantor T128, the
1420          * tighter 'C' code breaks and requires this) solves the problem - 
1421          * the 1 us delay is arbitrary, and only used because this delay will 
1422          * be the same on other platforms and since it works here, it should 
1423          * work there.
1424          *
1425          * wingel suggests that this could be due to failing to wait
1426          * one deskew delay.
1427          */
1428
1429         udelay(1);
1430
1431         dprintk(NDEBUG_SELECTION, ("scsi%d : selecting target %d\n", instance->host_no, scmd_id(cmd)));
1432
1433         /* 
1434          * The SCSI specification calls for a 250 ms timeout for the actual 
1435          * selection.
1436          */
1437
1438         timeout = jiffies + (250 * HZ / 1000);
1439
1440         /* 
1441          * XXX very interesting - we're seeing a bounce where the BSY we 
1442          * asserted is being reflected / still asserted (propagation delay?)
1443          * and it's detecting as true.  Sigh.
1444          */
1445
1446         hostdata->select_time = 0;      /* we count the clock ticks at which we polled */
1447         hostdata->selecting = cmd;
1448
1449 part2:
1450         /* RvC: here we enter after a sleeping period, or immediately after
1451            execution of part 1
1452            we poll only once ech clock tick */
1453         value = NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO);
1454
1455         if (!value && (hostdata->select_time < HZ/4)) {
1456                 /* RvC: we still must wait for a device response */
1457                 hostdata->select_time++;        /* after 25 ticks the device has failed */
1458                 NCR5380_set_timer(hostdata, 1);
1459                 return 0;       /* RvC: we return here with hostdata->selecting set,
1460                                    to go to sleep */
1461         }
1462
1463         hostdata->selecting = NULL;/* clear this pointer, because we passed the
1464                                            waiting period */
1465         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1466                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1467                 NCR5380_reselect(instance);
1468                 printk("scsi%d : reselection after won arbitration?\n", instance->host_no);
1469                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1470                 return -1;
1471         }
1472         /* 
1473          * No less than two deskew delays after the initiator detects the 
1474          * BSY signal is true, it shall release the SEL signal and may 
1475          * change the DATA BUS.                                     -wingel
1476          */
1477
1478         udelay(1);
1479
1480         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1481
1482         if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1483                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1484                 if (hostdata->targets_present & (1 << scmd_id(cmd))) {
1485                         printk(KERN_DEBUG "scsi%d : weirdness\n", instance->host_no);
1486                         if (hostdata->restart_select)
1487                                 printk(KERN_DEBUG "\trestart select\n");
1488                         NCR5380_dprint(NDEBUG_SELECTION, instance);
1489                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1490                         return -1;
1491                 }
1492                 cmd->result = DID_BAD_TARGET << 16;
1493                 collect_stats(hostdata, cmd);
1494                 cmd->scsi_done(cmd);
1495                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1496                 dprintk(NDEBUG_SELECTION, ("scsi%d : target did not respond within 250ms\n", instance->host_no));
1497                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1498                 return 0;
1499         }
1500         hostdata->targets_present |= (1 << scmd_id(cmd));
1501
1502         /*
1503          * Since we followed the SCSI spec, and raised ATN while SEL 
1504          * was true but before BSY was false during selection, the information
1505          * transfer phase should be a MESSAGE OUT phase so that we can send the
1506          * IDENTIFY message.
1507          * 
1508          * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1509          * message (2 bytes) with a tag ID that we increment with every command
1510          * until it wraps back to 0.
1511          *
1512          * XXX - it turns out that there are some broken SCSI-II devices,
1513          *       which claim to support tagged queuing but fail when more than
1514          *       some number of commands are issued at once.
1515          */
1516
1517         /* Wait for start of REQ/ACK handshake */
1518
1519         spin_unlock_irq(instance->host_lock);
1520         err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
1521         spin_lock_irq(instance->host_lock);
1522         
1523         if(err) {
1524                 printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__);
1525                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1526                 goto failed;
1527         }
1528
1529         dprintk(NDEBUG_SELECTION, ("scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id));
1530         tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun);
1531
1532         len = 1;
1533         cmd->tag = 0;
1534
1535         /* Send message(s) */
1536         data = tmp;
1537         phase = PHASE_MSGOUT;
1538         NCR5380_transfer_pio(instance, &phase, &len, &data);
1539         dprintk(NDEBUG_SELECTION, ("scsi%d : nexus established.\n", instance->host_no));
1540         /* XXX need to handle errors here */
1541         hostdata->connected = cmd;
1542         hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1543
1544         initialize_SCp(cmd);
1545
1546         return 0;
1547
1548         /* Selection failed */
1549 failed:
1550         return -1;
1551
1552 }
1553
1554 /* 
1555  * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, 
1556  *      unsigned char *phase, int *count, unsigned char **data)
1557  *
1558  * Purpose : transfers data in given phase using polled I/O
1559  *
1560  * Inputs : instance - instance of driver, *phase - pointer to 
1561  *      what phase is expected, *count - pointer to number of 
1562  *      bytes to transfer, **data - pointer to data pointer.
1563  * 
1564  * Returns : -1 when different phase is entered without transferring
1565  *      maximum number of bytes, 0 if all bytes or transfered or exit
1566  *      is in same phase.
1567  *
1568  *      Also, *phase, *count, *data are modified in place.
1569  *
1570  * XXX Note : handling for bus free may be useful.
1571  */
1572
1573 /*
1574  * Note : this code is not as quick as it could be, however it 
1575  * IS 100% reliable, and for the actual data transfer where speed
1576  * counts, we will always do a pseudo DMA or DMA transfer.
1577  */
1578
1579 static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1580         NCR5380_local_declare();
1581         unsigned char p = *phase, tmp;
1582         int c = *count;
1583         unsigned char *d = *data;
1584         /*
1585          *      RvC: some administrative data to process polling time
1586          */
1587         int break_allowed = 0;
1588         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1589         NCR5380_setup(instance);
1590
1591         if (!(p & SR_IO))
1592                 dprintk(NDEBUG_PIO, ("scsi%d : pio write %d bytes\n", instance->host_no, c));
1593         else
1594                 dprintk(NDEBUG_PIO, ("scsi%d : pio read %d bytes\n", instance->host_no, c));
1595
1596         /* 
1597          * The NCR5380 chip will only drive the SCSI bus when the 
1598          * phase specified in the appropriate bits of the TARGET COMMAND
1599          * REGISTER match the STATUS REGISTER
1600          */
1601
1602          NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1603
1604         /* RvC: don't know if this is necessary, but other SCSI I/O is short
1605          *      so breaks are not necessary there
1606          */
1607         if ((p == PHASE_DATAIN) || (p == PHASE_DATAOUT)) {
1608                 break_allowed = 1;
1609         }
1610         do {
1611                 /* 
1612                  * Wait for assertion of REQ, after which the phase bits will be 
1613                  * valid 
1614                  */
1615
1616                 /* RvC: we simply poll once, after that we stop temporarily
1617                  *      and let the device buffer fill up
1618                  *      if breaking is not allowed, we keep polling as long as needed
1619                  */
1620
1621                 /* FIXME */
1622                 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ) && !break_allowed);
1623                 if (!(tmp & SR_REQ)) {
1624                         /* timeout condition */
1625                         NCR5380_set_timer(hostdata, USLEEP_SLEEP);
1626                         break;
1627                 }
1628
1629                 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : REQ detected\n", instance->host_no));
1630
1631                 /* Check for phase mismatch */
1632                 if ((tmp & PHASE_MASK) != p) {
1633                         dprintk(NDEBUG_HANDSHAKE, ("scsi%d : phase mismatch\n", instance->host_no));
1634                         NCR5380_dprint_phase(NDEBUG_HANDSHAKE, instance);
1635                         break;
1636                 }
1637                 /* Do actual transfer from SCSI bus to / from memory */
1638                 if (!(p & SR_IO))
1639                         NCR5380_write(OUTPUT_DATA_REG, *d);
1640                 else
1641                         *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1642
1643                 ++d;
1644
1645                 /* 
1646                  * The SCSI standard suggests that in MSGOUT phase, the initiator
1647                  * should drop ATN on the last byte of the message phase
1648                  * after REQ has been asserted for the handshake but before
1649                  * the initiator raises ACK.
1650                  */
1651
1652                 if (!(p & SR_IO)) {
1653                         if (!((p & SR_MSG) && c > 1)) {
1654                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1655                                 NCR5380_dprint(NDEBUG_PIO, instance);
1656                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1657                         } else {
1658                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1659                                 NCR5380_dprint(NDEBUG_PIO, instance);
1660                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1661                         }
1662                 } else {
1663                         NCR5380_dprint(NDEBUG_PIO, instance);
1664                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1665                 }
1666
1667                 /* FIXME - if this fails bus reset ?? */
1668                 NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 5*HZ);
1669                 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : req false, handshake complete\n", instance->host_no));
1670
1671 /*
1672  * We have several special cases to consider during REQ/ACK handshaking : 
1673  * 1.  We were in MSGOUT phase, and we are on the last byte of the 
1674  *      message.  ATN must be dropped as ACK is dropped.
1675  *
1676  * 2.  We are in a MSGIN phase, and we are on the last byte of the  
1677  *      message.  We must exit with ACK asserted, so that the calling
1678  *      code may raise ATN before dropping ACK to reject the message.
1679  *
1680  * 3.  ACK and ATN are clear and the target may proceed as normal.
1681  */
1682                 if (!(p == PHASE_MSGIN && c == 1)) {
1683                         if (p == PHASE_MSGOUT && c > 1)
1684                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1685                         else
1686                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1687                 }
1688         } while (--c);
1689
1690         dprintk(NDEBUG_PIO, ("scsi%d : residual %d\n", instance->host_no, c));
1691
1692         *count = c;
1693         *data = d;
1694         tmp = NCR5380_read(STATUS_REG);
1695         if (tmp & SR_REQ)
1696                 *phase = tmp & PHASE_MASK;
1697         else
1698                 *phase = PHASE_UNKNOWN;
1699
1700         if (!c || (*phase == p))
1701                 return 0;
1702         else
1703                 return -1;
1704 }
1705
1706 /**
1707  *      do_reset        -       issue a reset command
1708  *      @host: adapter to reset
1709  *
1710  *      Issue a reset sequence to the NCR5380 and try and get the bus
1711  *      back into sane shape.
1712  *
1713  *      Locks: caller holds queue lock
1714  */
1715  
1716 static void do_reset(struct Scsi_Host *host) {
1717         NCR5380_local_declare();
1718         NCR5380_setup(host);
1719
1720         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
1721         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
1722         udelay(25);
1723         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1724 }
1725
1726 /*
1727  * Function : do_abort (Scsi_Host *host)
1728  * 
1729  * Purpose : abort the currently established nexus.  Should only be 
1730  *      called from a routine which can drop into a 
1731  * 
1732  * Returns : 0 on success, -1 on failure.
1733  *
1734  * Locks: queue lock held by caller
1735  *      FIXME: sort this out and get new_eh running
1736  */
1737
1738 static int do_abort(struct Scsi_Host *host) {
1739         NCR5380_local_declare();
1740         unsigned char *msgptr, phase, tmp;
1741         int len;
1742         int rc;
1743         NCR5380_setup(host);
1744
1745
1746         /* Request message out phase */
1747         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1748
1749         /* 
1750          * Wait for the target to indicate a valid phase by asserting 
1751          * REQ.  Once this happens, we'll have either a MSGOUT phase 
1752          * and can immediately send the ABORT message, or we'll have some 
1753          * other phase and will have to source/sink data.
1754          * 
1755          * We really don't care what value was on the bus or what value
1756          * the target sees, so we just handshake.
1757          */
1758
1759         rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, SR_REQ, 60 * HZ);
1760         
1761         if(rc < 0)
1762                 return -1;
1763
1764         tmp = (unsigned char)rc;
1765         
1766         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1767
1768         if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1769                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1770                 rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, 0, 3*HZ);
1771                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1772                 if(rc == -1)
1773                         return -1;
1774         }
1775         tmp = ABORT;
1776         msgptr = &tmp;
1777         len = 1;
1778         phase = PHASE_MSGOUT;
1779         NCR5380_transfer_pio(host, &phase, &len, &msgptr);
1780
1781         /*
1782          * If we got here, and the command completed successfully,
1783          * we're about to go into bus free state.
1784          */
1785
1786         return len ? -1 : 0;
1787 }
1788
1789 #if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL)
1790 /* 
1791  * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, 
1792  *      unsigned char *phase, int *count, unsigned char **data)
1793  *
1794  * Purpose : transfers data in given phase using either real
1795  *      or pseudo DMA.
1796  *
1797  * Inputs : instance - instance of driver, *phase - pointer to 
1798  *      what phase is expected, *count - pointer to number of 
1799  *      bytes to transfer, **data - pointer to data pointer.
1800  * 
1801  * Returns : -1 when different phase is entered without transferring
1802  *      maximum number of bytes, 0 if all bytes or transfered or exit
1803  *      is in same phase.
1804  *
1805  *      Also, *phase, *count, *data are modified in place.
1806  *
1807  *      Locks: io_request lock held by caller
1808  */
1809
1810
1811 static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1812         NCR5380_local_declare();
1813         register int c = *count;
1814         register unsigned char p = *phase;
1815         register unsigned char *d = *data;
1816         unsigned char tmp;
1817         int foo;
1818 #if defined(REAL_DMA_POLL)
1819         int cnt, toPIO;
1820         unsigned char saved_data = 0, overrun = 0, residue;
1821 #endif
1822
1823         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1824
1825         NCR5380_setup(instance);
1826
1827         if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1828                 *phase = tmp;
1829                 return -1;
1830         }
1831 #if defined(REAL_DMA) || defined(REAL_DMA_POLL)
1832 #ifdef READ_OVERRUNS
1833         if (p & SR_IO) {
1834                 c -= 2;
1835         }
1836 #endif
1837         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));
1838         hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c);
1839 #endif
1840
1841         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1842
1843 #ifdef REAL_DMA
1844         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1845 #elif defined(REAL_DMA_POLL)
1846         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1847 #else
1848         /*
1849          * Note : on my sample board, watch-dog timeouts occurred when interrupts
1850          * were not disabled for the duration of a single DMA transfer, from 
1851          * before the setting of DMA mode to after transfer of the last byte.
1852          */
1853
1854 #if defined(PSEUDO_DMA) && defined(UNSAFE)
1855         spin_unlock_irq(instance->host_lock);
1856 #endif
1857         /* KLL May need eop and parity in 53c400 */
1858         if (hostdata->flags & FLAG_NCR53C400)
1859                 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_PAR_CHECK | MR_ENABLE_PAR_INTR | MR_ENABLE_EOP_INTR | MR_DMA_MODE | MR_MONITOR_BSY);
1860         else
1861                 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1862 #endif                          /* def REAL_DMA */
1863
1864         dprintk(NDEBUG_DMA, ("scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG)));
1865
1866         /* 
1867          *      On the PAS16 at least I/O recovery delays are not needed here.
1868          *      Everyone else seems to want them.
1869          */
1870
1871         if (p & SR_IO) {
1872                 io_recovery_delay(1);
1873                 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1874         } else {
1875                 io_recovery_delay(1);
1876                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1877                 io_recovery_delay(1);
1878                 NCR5380_write(START_DMA_SEND_REG, 0);
1879                 io_recovery_delay(1);
1880         }
1881
1882 #if defined(REAL_DMA_POLL)
1883         do {
1884                 tmp = NCR5380_read(BUS_AND_STATUS_REG);
1885         } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER)));
1886
1887 /*
1888    At this point, either we've completed DMA, or we have a phase mismatch,
1889    or we've unexpectedly lost BUSY (which is a real error).
1890
1891    For write DMAs, we want to wait until the last byte has been
1892    transferred out over the bus before we turn off DMA mode.  Alas, there
1893    seems to be no terribly good way of doing this on a 5380 under all
1894    conditions.  For non-scatter-gather operations, we can wait until REQ
1895    and ACK both go false, or until a phase mismatch occurs.  Gather-writes
1896    are nastier, since the device will be expecting more data than we
1897    are prepared to send it, and REQ will remain asserted.  On a 53C8[01] we
1898    could test LAST BIT SENT to assure transfer (I imagine this is precisely
1899    why this signal was added to the newer chips) but on the older 538[01]
1900    this signal does not exist.  The workaround for this lack is a watchdog;
1901    we bail out of the wait-loop after a modest amount of wait-time if
1902    the usual exit conditions are not met.  Not a terribly clean or
1903    correct solution :-%
1904
1905    Reads are equally tricky due to a nasty characteristic of the NCR5380.
1906    If the chip is in DMA mode for an READ, it will respond to a target's
1907    REQ by latching the SCSI data into the INPUT DATA register and asserting
1908    ACK, even if it has _already_ been notified by the DMA controller that
1909    the current DMA transfer has completed!  If the NCR5380 is then taken
1910    out of DMA mode, this already-acknowledged byte is lost.
1911
1912    This is not a problem for "one DMA transfer per command" reads, because
1913    the situation will never arise... either all of the data is DMA'ed
1914    properly, or the target switches to MESSAGE IN phase to signal a
1915    disconnection (either operation bringing the DMA to a clean halt).
1916    However, in order to handle scatter-reads, we must work around the
1917    problem.  The chosen fix is to DMA N-2 bytes, then check for the
1918    condition before taking the NCR5380 out of DMA mode.  One or two extra
1919    bytes are transferred via PIO as necessary to fill out the original
1920    request.
1921  */
1922
1923         if (p & SR_IO) {
1924 #ifdef READ_OVERRUNS
1925                 udelay(10);
1926                 if (((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == (BASR_PHASE_MATCH | BASR_ACK))) {
1927                         saved_data = NCR5380_read(INPUT_DATA_REGISTER);
1928                         overrun = 1;
1929                 }
1930 #endif
1931         } else {
1932                 int limit = 100;
1933                 while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) {
1934                         if (!(tmp & BASR_PHASE_MATCH))
1935                                 break;
1936                         if (--limit < 0)
1937                                 break;
1938                 }
1939         }
1940
1941         dprintk(NDEBUG_DMA, ("scsi%d : polled DMA transfer complete, basr 0x%X, sr 0x%X\n", instance->host_no, tmp, NCR5380_read(STATUS_REG)));
1942
1943         NCR5380_write(MODE_REG, MR_BASE);
1944         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1945
1946         residue = NCR5380_dma_residual(instance);
1947         c -= residue;
1948         *count -= c;
1949         *data += c;
1950         *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
1951
1952 #ifdef READ_OVERRUNS
1953         if (*phase == p && (p & SR_IO) && residue == 0) {
1954                 if (overrun) {
1955                         dprintk(NDEBUG_DMA, ("Got an input overrun, using saved byte\n"));
1956                         **data = saved_data;
1957                         *data += 1;
1958                         *count -= 1;
1959                         cnt = toPIO = 1;
1960                 } else {
1961                         printk("No overrun??\n");
1962                         cnt = toPIO = 2;
1963                 }
1964                 dprintk(NDEBUG_DMA, ("Doing %d-byte PIO to 0x%X\n", cnt, *data));
1965                 NCR5380_transfer_pio(instance, phase, &cnt, data);
1966                 *count -= toPIO - cnt;
1967         }
1968 #endif
1969
1970         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)));
1971         return 0;
1972
1973 #elif defined(REAL_DMA)
1974         return 0;
1975 #else                           /* defined(REAL_DMA_POLL) */
1976         if (p & SR_IO) {
1977 #ifdef DMA_WORKS_RIGHT
1978                 foo = NCR5380_pread(instance, d, c);
1979 #else
1980                 int diff = 1;
1981                 if (hostdata->flags & FLAG_NCR53C400) {
1982                         diff = 0;
1983                 }
1984                 if (!(foo = NCR5380_pread(instance, d, c - diff))) {
1985                         /*
1986                          * We can't disable DMA mode after successfully transferring 
1987                          * what we plan to be the last byte, since that would open up
1988                          * a race condition where if the target asserted REQ before 
1989                          * we got the DMA mode reset, the NCR5380 would have latched
1990                          * an additional byte into the INPUT DATA register and we'd
1991                          * have dropped it.
1992                          * 
1993                          * The workaround was to transfer one fewer bytes than we 
1994                          * intended to with the pseudo-DMA read function, wait for 
1995                          * the chip to latch the last byte, read it, and then disable
1996                          * pseudo-DMA mode.
1997                          * 
1998                          * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
1999                          * REQ is deasserted when ACK is asserted, and not reasserted
2000                          * until ACK goes false.  Since the NCR5380 won't lower ACK
2001                          * until DACK is asserted, which won't happen unless we twiddle
2002                          * the DMA port or we take the NCR5380 out of DMA mode, we 
2003                          * can guarantee that we won't handshake another extra 
2004                          * byte.
2005                          */
2006
2007                         if (!(hostdata->flags & FLAG_NCR53C400)) {
2008                                 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ));
2009                                 /* Wait for clean handshake */
2010                                 while (NCR5380_read(STATUS_REG) & SR_REQ);
2011                                 d[c - 1] = NCR5380_read(INPUT_DATA_REG);
2012                         }
2013                 }
2014 #endif
2015         } else {
2016 #ifdef DMA_WORKS_RIGHT
2017                 foo = NCR5380_pwrite(instance, d, c);
2018 #else
2019                 int timeout;
2020                 dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c));
2021                 if (!(foo = NCR5380_pwrite(instance, d, c))) {
2022                         /*
2023                          * Wait for the last byte to be sent.  If REQ is being asserted for 
2024                          * the byte we're interested, we'll ACK it and it will go false.  
2025                          */
2026                         if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) {
2027                                 timeout = 20000;
2028                                 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH));
2029
2030                                 if (!timeout)
2031                                         dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no));
2032
2033                                 if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) {
2034                                         hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT;
2035                                         if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) {
2036                                                 hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT;
2037                                                 dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no));
2038                                         }
2039                                 }
2040                         } else {
2041                                 dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n"));
2042                                 while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT));
2043                                 dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n"));
2044                         }
2045                 }
2046 #endif
2047         }
2048         NCR5380_write(MODE_REG, MR_BASE);
2049         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2050
2051         if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) {
2052                 dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n"));
2053                 if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) {
2054                         dprintk(NDEBUG_C400_PWRITE, ("53C400w:    got it, reading reset interrupt reg\n"));
2055                         NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2056                 } else {
2057                         printk("53C400w:    IRQ NOT THERE!\n");
2058                 }
2059         }
2060         *data = d + c;
2061         *count = 0;
2062         *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
2063 #if defined(PSEUDO_DMA) && defined(UNSAFE)
2064         spin_lock_irq(instance->host_lock);
2065 #endif                          /* defined(REAL_DMA_POLL) */
2066         return foo;
2067 #endif                          /* def REAL_DMA */
2068 }
2069 #endif                          /* defined(REAL_DMA) | defined(PSEUDO_DMA) */
2070
2071 /*
2072  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
2073  *
2074  * Purpose : run through the various SCSI phases and do as the target 
2075  *      directs us to.  Operates on the currently connected command, 
2076  *      instance->connected.
2077  *
2078  * Inputs : instance, instance for which we are doing commands
2079  *
2080  * Side effects : SCSI things happen, the disconnected queue will be 
2081  *      modified if a command disconnects, *instance->connected will
2082  *      change.
2083  *
2084  * XXX Note : we need to watch for bus free or a reset condition here 
2085  *      to recover from an unexpected bus free condition.
2086  *
2087  * Locks: io_request_lock held by caller in IRQ mode
2088  */
2089
2090 static void NCR5380_information_transfer(struct Scsi_Host *instance) {
2091         NCR5380_local_declare();
2092         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata;
2093         unsigned char msgout = NOP;
2094         int sink = 0;
2095         int len;
2096 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2097         int transfersize;
2098 #endif
2099         unsigned char *data;
2100         unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2101         Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2102         /* RvC: we need to set the end of the polling time */
2103         unsigned long poll_time = jiffies + USLEEP_POLL;
2104
2105         NCR5380_setup(instance);
2106
2107         while (1) {
2108                 tmp = NCR5380_read(STATUS_REG);
2109                 /* We only have a valid SCSI phase when REQ is asserted */
2110                 if (tmp & SR_REQ) {
2111                         phase = (tmp & PHASE_MASK);
2112                         if (phase != old_phase) {
2113                                 old_phase = phase;
2114                                 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
2115                         }
2116                         if (sink && (phase != PHASE_MSGOUT)) {
2117                                 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2118
2119                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
2120                                 while (NCR5380_read(STATUS_REG) & SR_REQ);
2121                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2122                                 sink = 0;
2123                                 continue;
2124                         }
2125                         switch (phase) {
2126                         case PHASE_DATAIN:
2127                         case PHASE_DATAOUT:
2128 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2129                                 printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no);
2130                                 sink = 1;
2131                                 do_abort(instance);
2132                                 cmd->result = DID_ERROR << 16;
2133                                 cmd->scsi_done(cmd);
2134                                 return;
2135 #endif
2136                                 /* 
2137                                  * If there is no room left in the current buffer in the
2138                                  * scatter-gather list, move onto the next one.
2139                                  */
2140
2141                                 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2142                                         ++cmd->SCp.buffer;
2143                                         --cmd->SCp.buffers_residual;
2144                                         cmd->SCp.this_residual = cmd->SCp.buffer->length;
2145                                         cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2146                                         dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual));
2147                                 }
2148                                 /*
2149                                  * The preferred transfer method is going to be 
2150                                  * PSEUDO-DMA for systems that are strictly PIO,
2151                                  * since we can let the hardware do the handshaking.
2152                                  *
2153                                  * For this to work, we need to know the transfersize
2154                                  * ahead of time, since the pseudo-DMA code will sit
2155                                  * in an unconditional loop.
2156                                  */
2157
2158 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2159                                 /* KLL
2160                                  * PSEUDO_DMA is defined here. If this is the g_NCR5380
2161                                  * driver then it will always be defined, so the
2162                                  * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base
2163                                  * NCR5380 case.  I think this is a fairly clean solution.
2164                                  * We supplement these 2 if's with the flag.
2165                                  */
2166 #ifdef NCR5380_dma_xfer_len
2167                                 if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) {
2168 #else
2169                                 transfersize = cmd->transfersize;
2170
2171 #ifdef LIMIT_TRANSFERSIZE       /* If we have problems with interrupt service */
2172                                 if (transfersize > 512)
2173                                         transfersize = 512;
2174 #endif                          /* LIMIT_TRANSFERSIZE */
2175
2176                                 if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) {
2177                                         /* Limit transfers to 32K, for xx400 & xx406
2178                                          * pseudoDMA that transfers in 128 bytes blocks. */
2179                                         if (transfersize > 32 * 1024)
2180                                                 transfersize = 32 * 1024;
2181 #endif
2182                                         len = transfersize;
2183                                         if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) {
2184                                                 /*
2185                                                  * If the watchdog timer fires, all future accesses to this
2186                                                  * device will use the polled-IO.
2187                                                  */
2188                                                 scmd_printk(KERN_INFO, cmd,
2189                                                             "switching to slow handshake\n");
2190                                                 cmd->device->borken = 1;
2191                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2192                                                 sink = 1;
2193                                                 do_abort(instance);
2194                                                 cmd->result = DID_ERROR << 16;
2195                                                 cmd->scsi_done(cmd);
2196                                                 /* XXX - need to source or sink data here, as appropriate */
2197                                         } else
2198                                                 cmd->SCp.this_residual -= transfersize - len;
2199                                 } else
2200 #endif                          /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */
2201                                         NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **)
2202                                                              &cmd->SCp.ptr);
2203                                 break;
2204                         case PHASE_MSGIN:
2205                                 len = 1;
2206                                 data = &tmp;
2207                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2208                                 cmd->SCp.Message = tmp;
2209
2210                                 switch (tmp) {
2211                                         /*
2212                                          * Linking lets us reduce the time required to get the 
2213                                          * next command out to the device, hopefully this will
2214                                          * mean we don't waste another revolution due to the delays
2215                                          * required by ARBITRATION and another SELECTION.
2216                                          *
2217                                          * In the current implementation proposal, low level drivers
2218                                          * merely have to start the next command, pointed to by 
2219                                          * next_link, done() is called as with unlinked commands.
2220                                          */
2221 #ifdef LINKED
2222                                 case LINKED_CMD_COMPLETE:
2223                                 case LINKED_FLG_CMD_COMPLETE:
2224                                         /* Accept message by clearing ACK */
2225                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2226                                         dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun));
2227                                         /* 
2228                                          * Sanity check : A linked command should only terminate with
2229                                          * one of these messages if there are more linked commands
2230                                          * available.
2231                                          */
2232                                         if (!cmd->next_link) {
2233                                                 printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun);
2234                                                 sink = 1;
2235                                                 do_abort(instance);
2236                                                 return;
2237                                         }
2238                                         initialize_SCp(cmd->next_link);
2239                                         /* The next command is still part of this process */
2240                                         cmd->next_link->tag = cmd->tag;
2241                                         cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2242                                         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));
2243                                         collect_stats(hostdata, cmd);
2244                                         cmd->scsi_done(cmd);
2245                                         cmd = hostdata->connected;
2246                                         break;
2247 #endif                          /* def LINKED */
2248                                 case ABORT:
2249                                 case COMMAND_COMPLETE:
2250                                         /* Accept message by clearing ACK */
2251                                         sink = 1;
2252                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2253                                         hostdata->connected = NULL;
2254                                         dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun));
2255                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2256
2257                                         /* 
2258                                          * I'm not sure what the correct thing to do here is : 
2259                                          * 
2260                                          * If the command that just executed is NOT a request 
2261                                          * sense, the obvious thing to do is to set the result
2262                                          * code to the values of the stored parameters.
2263                                          * 
2264                                          * If it was a REQUEST SENSE command, we need some way 
2265                                          * to differentiate between the failure code of the original
2266                                          * and the failure code of the REQUEST sense - the obvious
2267                                          * case is success, where we fall through and leave the result
2268                                          * code unchanged.
2269                                          * 
2270                                          * The non-obvious place is where the REQUEST SENSE failed 
2271                                          */
2272
2273                                         if (cmd->cmnd[0] != REQUEST_SENSE)
2274                                                 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2275                                         else if (status_byte(cmd->SCp.Status) != GOOD)
2276                                                 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2277
2278 #ifdef AUTOSENSE
2279                                         if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2280                                                 hostdata->ses.cmd_len) {
2281                                                 scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2282                                                 hostdata->ses.cmd_len = 0 ;
2283                                         }
2284
2285                                         if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2286                                                 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2287
2288                                                 dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no));
2289
2290                                                 LIST(cmd, hostdata->issue_queue);
2291                                                 cmd->host_scribble = (unsigned char *)
2292                                                     hostdata->issue_queue;
2293                                                 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2294                                                 dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no));
2295                                         } else
2296 #endif                          /* def AUTOSENSE */
2297                                         {
2298                                                 collect_stats(hostdata, cmd);
2299                                                 cmd->scsi_done(cmd);
2300                                         }
2301
2302                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2303                                         /* 
2304                                          * Restore phase bits to 0 so an interrupted selection, 
2305                                          * arbitration can resume.
2306                                          */
2307                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2308
2309                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2310                                                 barrier();
2311                                         return;
2312                                 case MESSAGE_REJECT:
2313                                         /* Accept message by clearing ACK */
2314                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2315                                         switch (hostdata->last_message) {
2316                                         case HEAD_OF_QUEUE_TAG:
2317                                         case ORDERED_QUEUE_TAG:
2318                                         case SIMPLE_QUEUE_TAG:
2319                                                 cmd->device->simple_tags = 0;
2320                                                 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2321                                                 break;
2322                                         default:
2323                                                 break;
2324                                         }
2325                                 case DISCONNECT:{
2326                                                 /* Accept message by clearing ACK */
2327                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2328                                                 cmd->device->disconnect = 1;
2329                                                 LIST(cmd, hostdata->disconnected_queue);
2330                                                 cmd->host_scribble = (unsigned char *)
2331                                                     hostdata->disconnected_queue;
2332                                                 hostdata->connected = NULL;
2333                                                 hostdata->disconnected_queue = cmd;
2334                                                 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));
2335                                                 /* 
2336                                                  * Restore phase bits to 0 so an interrupted selection, 
2337                                                  * arbitration can resume.
2338                                                  */
2339                                                 NCR5380_write(TARGET_COMMAND_REG, 0);
2340
2341                                                 /* Enable reselect interrupts */
2342                                                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2343                                                 /* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/
2344                                                 /* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */
2345                                                 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2346                                                         barrier();
2347                                                 return;
2348                                         }
2349                                         /* 
2350                                          * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2351                                          * operation, in violation of the SCSI spec so we can safely 
2352                                          * ignore SAVE/RESTORE pointers calls.
2353                                          *
2354                                          * Unfortunately, some disks violate the SCSI spec and 
2355                                          * don't issue the required SAVE_POINTERS message before
2356                                          * disconnecting, and we have to break spec to remain 
2357                                          * compatible.
2358                                          */
2359                                 case SAVE_POINTERS:
2360                                 case RESTORE_POINTERS:
2361                                         /* Accept message by clearing ACK */
2362                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2363                                         break;
2364                                 case EXTENDED_MESSAGE:
2365 /* 
2366  * Extended messages are sent in the following format :
2367  * Byte         
2368  * 0            EXTENDED_MESSAGE == 1
2369  * 1            length (includes one byte for code, doesn't 
2370  *              include first two bytes)
2371  * 2            code
2372  * 3..length+1  arguments
2373  *
2374  * Start the extended message buffer with the EXTENDED_MESSAGE
2375  * byte, since spi_print_msg() wants the whole thing.  
2376  */
2377                                         extended_msg[0] = EXTENDED_MESSAGE;
2378                                         /* Accept first byte by clearing ACK */
2379                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2380                                         dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no));
2381
2382                                         len = 2;
2383                                         data = extended_msg + 1;
2384                                         phase = PHASE_MSGIN;
2385                                         NCR5380_transfer_pio(instance, &phase, &len, &data);
2386
2387                                         dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2]));
2388
2389                                         if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) {
2390                                                 /* Accept third byte by clearing ACK */
2391                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2392                                                 len = extended_msg[1] - 1;
2393                                                 data = extended_msg + 3;
2394                                                 phase = PHASE_MSGIN;
2395
2396                                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2397                                                 dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len));
2398
2399                                                 switch (extended_msg[2]) {
2400                                                 case EXTENDED_SDTR:
2401                                                 case EXTENDED_WDTR:
2402                                                 case EXTENDED_MODIFY_DATA_POINTER:
2403                                                 case EXTENDED_EXTENDED_IDENTIFY:
2404                                                         tmp = 0;
2405                                                 }
2406                                         } else if (len) {
2407                                                 printk("scsi%d: error receiving extended message\n", instance->host_no);
2408                                                 tmp = 0;
2409                                         } else {
2410                                                 printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]);
2411                                                 tmp = 0;
2412                                         }
2413                                         /* Fall through to reject message */
2414
2415                                         /* 
2416                                          * If we get something weird that we aren't expecting, 
2417                                          * reject it.
2418                                          */
2419                                 default:
2420                                         if (!tmp) {
2421                                                 printk("scsi%d: rejecting message ", instance->host_no);
2422                                                 spi_print_msg(extended_msg);
2423                                                 printk("\n");
2424                                         } else if (tmp != EXTENDED_MESSAGE)
2425                                                 scmd_printk(KERN_INFO, cmd,
2426                                                         "rejecting unknown message %02x\n",tmp);
2427                                         else
2428                                                 scmd_printk(KERN_INFO, cmd,
2429                                                         "rejecting unknown extended message code %02x, length %d\n", extended_msg[1], extended_msg[0]);
2430
2431                                         msgout = MESSAGE_REJECT;
2432                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2433                                         break;
2434                                 }       /* switch (tmp) */
2435                                 break;
2436                         case PHASE_MSGOUT:
2437                                 len = 1;
2438                                 data = &msgout;
2439                                 hostdata->last_message = msgout;
2440                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2441                                 if (msgout == ABORT) {
2442                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2443                                         hostdata->connected = NULL;
2444                                         cmd->result = DID_ERROR << 16;
2445                                         collect_stats(hostdata, cmd);
2446                                         cmd->scsi_done(cmd);
2447                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2448                                         return;
2449                                 }
2450                                 msgout = NOP;
2451                                 break;
2452                         case PHASE_CMDOUT:
2453                                 len = cmd->cmd_len;
2454                                 data = cmd->cmnd;
2455                                 /* 
2456                                  * XXX for performance reasons, on machines with a 
2457                                  * PSEUDO-DMA architecture we should probably 
2458                                  * use the dma transfer function.  
2459                                  */
2460                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2461                                 if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) {
2462                                         NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2463                                         dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2464                                         return;
2465                                 }
2466                                 break;
2467                         case PHASE_STATIN:
2468                                 len = 1;
2469                                 data = &tmp;
2470                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2471                                 cmd->SCp.Status = tmp;
2472                                 break;
2473                         default:
2474                                 printk("scsi%d : unknown phase\n", instance->host_no);
2475                                 NCR5380_dprint(NDEBUG_ALL, instance);
2476                         }       /* switch(phase) */
2477                 }               /* if (tmp * SR_REQ) */
2478                 else {
2479                         /* RvC: go to sleep if polling time expired
2480                          */
2481                         if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) {
2482                                 NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2483                                 dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2484                                 return;
2485                         }
2486                 }
2487         }                       /* while (1) */
2488 }
2489
2490 /*
2491  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2492  *
2493  * Purpose : does reselection, initializing the instance->connected 
2494  *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q 
2495  *      nexus has been reestablished,
2496  *      
2497  * Inputs : instance - this instance of the NCR5380.
2498  *
2499  * Locks: io_request_lock held by caller if IRQ driven
2500  */
2501
2502 static void NCR5380_reselect(struct Scsi_Host *instance) {
2503         NCR5380_local_declare();
2504         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)
2505          instance->hostdata;
2506         unsigned char target_mask;
2507         unsigned char lun, phase;
2508         int len;
2509         unsigned char msg[3];
2510         unsigned char *data;
2511         Scsi_Cmnd *tmp = NULL, *prev;
2512         int abort = 0;
2513         NCR5380_setup(instance);
2514
2515         /*
2516          * Disable arbitration, etc. since the host adapter obviously
2517          * lost, and tell an interrupted NCR5380_select() to restart.
2518          */
2519
2520         NCR5380_write(MODE_REG, MR_BASE);
2521         hostdata->restart_select = 1;
2522
2523         target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2524         dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no));
2525
2526         /* 
2527          * At this point, we have detected that our SCSI ID is on the bus,
2528          * SEL is true and BSY was false for at least one bus settle delay
2529          * (400 ns).
2530          *
2531          * We must assert BSY ourselves, until the target drops the SEL
2532          * signal.
2533          */
2534
2535         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2536
2537         /* FIXME: timeout too long, must fail to workqueue */   
2538         if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0)
2539                 abort = 1;
2540                 
2541         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2542
2543         /*
2544          * Wait for target to go into MSGIN.
2545          * FIXME: timeout needed and fail to work queeu
2546          */
2547
2548         if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ))
2549                 abort = 1;
2550
2551         len = 1;
2552         data = msg;
2553         phase = PHASE_MSGIN;
2554         NCR5380_transfer_pio(instance, &phase, &len, &data);
2555
2556         if (!(msg[0] & 0x80)) {
2557                 printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no);
2558                 spi_print_msg(msg);
2559                 abort = 1;
2560         } else {
2561                 /* Accept message by clearing ACK */
2562                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2563                 lun = (msg[0] & 0x07);
2564
2565                 /* 
2566                  * We need to add code for SCSI-II to track which devices have
2567                  * I_T_L_Q nexuses established, and which have simple I_T_L
2568                  * nexuses so we can chose to do additional data transfer.
2569                  */
2570
2571                 /* 
2572                  * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we 
2573                  * just reestablished, and remove it from the disconnected queue.
2574                  */
2575
2576
2577                 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
2578                         if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2579                             ) {
2580                                 if (prev) {
2581                                         REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
2582                                         prev->host_scribble = tmp->host_scribble;
2583                                 } else {
2584                                         REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble);
2585                                         hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble;
2586                                 }
2587                                 tmp->host_scribble = NULL;
2588                                 break;
2589                         }
2590                 if (!tmp) {
2591                         printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun);
2592                         /* 
2593                          * Since we have an established nexus that we can't do anything with,
2594                          * we must abort it.  
2595                          */
2596                         abort = 1;
2597                 }
2598         }
2599
2600         if (abort) {
2601                 do_abort(instance);
2602         } else {
2603                 hostdata->connected = tmp;
2604                 dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag));
2605         }
2606 }
2607
2608 /*
2609  * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
2610  *
2611  * Purpose : called by interrupt handler when DMA finishes or a phase
2612  *      mismatch occurs (which would finish the DMA transfer).  
2613  *
2614  * Inputs : instance - this instance of the NCR5380.
2615  *
2616  * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L
2617  *      nexus has been reestablished, on failure NULL is returned.
2618  */
2619
2620 #ifdef REAL_DMA
2621 static void NCR5380_dma_complete(NCR5380_instance * instance) {
2622         NCR5380_local_declare();
2623         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2624         int transferred;
2625         NCR5380_setup(instance);
2626
2627         /*
2628          * XXX this might not be right.
2629          *
2630          * Wait for final byte to transfer, ie wait for ACK to go false.
2631          *
2632          * We should use the Last Byte Sent bit, unfortunately this is 
2633          * not available on the 5380/5381 (only the various CMOS chips)
2634          *
2635          * FIXME: timeout, and need to handle long timeout/irq case
2636          */
2637
2638         NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ);
2639
2640         NCR5380_write(MODE_REG, MR_BASE);
2641         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2642
2643         /*
2644          * The only places we should see a phase mismatch and have to send
2645          * data from the same set of pointers will be the data transfer
2646          * phases.  So, residual, requested length are only important here.
2647          */
2648
2649         if (!(hostdata->connected->SCp.phase & SR_CD)) {
2650                 transferred = instance->dmalen - NCR5380_dma_residual();
2651                 hostdata->connected->SCp.this_residual -= transferred;
2652                 hostdata->connected->SCp.ptr += transferred;
2653         }
2654 }
2655 #endif                          /* def REAL_DMA */
2656
2657 /*
2658  * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2659  *
2660  * Purpose : abort a command
2661  *
2662  * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the 
2663  *      host byte of the result field to, if zero DID_ABORTED is 
2664  *      used.
2665  *
2666  * Returns : 0 - success, -1 on failure.
2667  *
2668  *      XXX - there is no way to abort the command that is currently 
2669  *      connected, you have to wait for it to complete.  If this is 
2670  *      a problem, we could implement longjmp() / setjmp(), setjmp()
2671  *      called where the loop started in NCR5380_main().
2672  *
2673  * Locks: host lock taken by caller
2674  */
2675
2676 static int NCR5380_abort(Scsi_Cmnd * cmd) {
2677         NCR5380_local_declare();
2678         struct Scsi_Host *instance = cmd->device->host;
2679         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2680         Scsi_Cmnd *tmp, **prev;
2681         
2682         printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no);
2683         scsi_print_command(cmd);
2684
2685         NCR5380_print_status(instance);
2686
2687         NCR5380_setup(instance);
2688
2689         dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no));
2690         dprintk(NDEBUG_ABORT, ("        basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)));
2691
2692 #if 0
2693 /*
2694  * Case 1 : If the command is the currently executing command, 
2695  * we'll set the aborted flag and return control so that 
2696  * information transfer routine can exit cleanly.
2697  */
2698
2699         if (hostdata->connected == cmd) {
2700                 dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no));
2701                 hostdata->aborted = 1;
2702 /*
2703  * We should perform BSY checking, and make sure we haven't slipped
2704  * into BUS FREE.
2705  */
2706
2707                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN);
2708 /* 
2709  * Since we can't change phases until we've completed the current 
2710  * handshake, we have to source or sink a byte of data if the current
2711  * phase is not MSGOUT.
2712  */
2713
2714 /* 
2715  * Return control to the executing NCR drive so we can clear the
2716  * aborted flag and get back into our main loop.
2717  */
2718
2719                 return 0;
2720         }
2721 #endif
2722
2723 /* 
2724  * Case 2 : If the command hasn't been issued yet, we simply remove it 
2725  *          from the issue queue.
2726  */
2727  
2728         dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no));
2729         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)
2730                 if (cmd == tmp) {
2731                         REMOVE(5, *prev, tmp, tmp->host_scribble);
2732                         (*prev) = (Scsi_Cmnd *) tmp->host_scribble;
2733                         tmp->host_scribble = NULL;
2734                         tmp->result = DID_ABORT << 16;
2735                         dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no));
2736                         tmp->scsi_done(tmp);
2737                         return SUCCESS;
2738                 }
2739 #if (NDEBUG  & NDEBUG_ABORT)
2740         /* KLL */
2741                 else if (prev == tmp)
2742                         printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no);
2743 #endif
2744
2745 /* 
2746  * Case 3 : If any commands are connected, we're going to fail the abort
2747  *          and let the high level SCSI driver retry at a later time or 
2748  *          issue a reset.
2749  *
2750  *          Timeouts, and therefore aborted commands, will be highly unlikely
2751  *          and handling them cleanly in this situation would make the common
2752  *          case of noresets less efficient, and would pollute our code.  So,
2753  *          we fail.
2754  */
2755
2756         if (hostdata->connected) {
2757                 dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no));
2758                 return FAILED;
2759         }
2760 /*
2761  * Case 4: If the command is currently disconnected from the bus, and 
2762  *      there are no connected commands, we reconnect the I_T_L or 
2763  *      I_T_L_Q nexus associated with it, go into message out, and send 
2764  *      an abort message.
2765  *
2766  * This case is especially ugly. In order to reestablish the nexus, we
2767  * need to call NCR5380_select().  The easiest way to implement this 
2768  * function was to abort if the bus was busy, and let the interrupt
2769  * handler triggered on the SEL for reselect take care of lost arbitrations
2770  * where necessary, meaning interrupts need to be enabled.
2771  *
2772  * When interrupts are enabled, the queues may change - so we 
2773  * can't remove it from the disconnected queue before selecting it
2774  * because that could cause a failure in hashing the nexus if that 
2775  * device reselected.
2776  * 
2777  * Since the queues may change, we can't use the pointers from when we
2778  * first locate it.
2779  *
2780  * So, we must first locate the command, and if NCR5380_select()
2781  * succeeds, then issue the abort, relocate the command and remove
2782  * it from the disconnected queue.
2783  */
2784
2785         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble)
2786                 if (cmd == tmp) {
2787                         dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no));
2788
2789                         if (NCR5380_select(instance, cmd, (int) cmd->tag))
2790                                 return FAILED;
2791                         dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no));
2792
2793                         do_abort(instance);
2794
2795                         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)
2796                                 if (cmd == tmp) {
2797                                         REMOVE(5, *prev, tmp, tmp->host_scribble);
2798                                         *prev = (Scsi_Cmnd *) tmp->host_scribble;
2799                                         tmp->host_scribble = NULL;
2800                                         tmp->result = DID_ABORT << 16;
2801                                         tmp->scsi_done(tmp);
2802                                         return SUCCESS;
2803                                 }
2804                 }
2805 /*
2806  * Case 5 : If we reached this point, the command was not found in any of 
2807  *          the queues.
2808  *
2809  * We probably reached this point because of an unlikely race condition
2810  * between the command completing successfully and the abortion code,
2811  * so we won't panic, but we will notify the user in case something really
2812  * broke.
2813  */
2814         printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n"
2815                         "         before abortion\n", instance->host_no);
2816         return FAILED;
2817 }
2818
2819
2820 /* 
2821  * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd)
2822  * 
2823  * Purpose : reset the SCSI bus.
2824  *
2825  * Returns : SUCCESS
2826  *
2827  * Locks: host lock taken by caller
2828  */
2829
2830 static int NCR5380_bus_reset(Scsi_Cmnd * cmd)
2831 {
2832         struct Scsi_Host *instance = cmd->device->host;
2833
2834         NCR5380_local_declare();
2835         NCR5380_setup(instance);
2836         NCR5380_print_status(instance);
2837
2838         spin_lock_irq(instance->host_lock);
2839         do_reset(instance);
2840         spin_unlock_irq(instance->host_lock);
2841
2842         return SUCCESS;
2843 }