[SCSI] NCR5380: fix undefined preprocessor identifier
[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
91 #ifndef NDEBUG
92 #define NDEBUG 0
93 #endif
94 #ifndef NDEBUG_ABORT
95 #define NDEBUG_ABORT 0
96 #endif
97
98 #if (NDEBUG & NDEBUG_LISTS)
99 #define LIST(x,y) {printk("LINE:%d   Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); if ((x)==(y)) udelay(5); }
100 #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); }
101 #else
102 #define LIST(x,y)
103 #define REMOVE(w,x,y,z)
104 #endif
105
106 #ifndef notyet
107 #undef LINKED
108 #undef REAL_DMA
109 #endif
110
111 #ifdef REAL_DMA_POLL
112 #undef READ_OVERRUNS
113 #define READ_OVERRUNS
114 #endif
115
116 #ifdef BOARD_REQUIRES_NO_DELAY
117 #define io_recovery_delay(x)
118 #else
119 #define io_recovery_delay(x)    udelay(x)
120 #endif
121
122 /*
123  * Design
124  *
125  * This is a generic 5380 driver.  To use it on a different platform, 
126  * one simply writes appropriate system specific macros (ie, data
127  * transfer - some PC's will use the I/O bus, 68K's must use 
128  * memory mapped) and drops this file in their 'C' wrapper.
129  *
130  * (Note from hch:  unfortunately it was not enough for the different
131  * m68k folks and instead of improving this driver they copied it
132  * and hacked it up for their needs.  As a consequence they lost
133  * most updates to this driver.  Maybe someone will fix all these
134  * drivers to use a common core one day..)
135  *
136  * As far as command queueing, two queues are maintained for 
137  * each 5380 in the system - commands that haven't been issued yet,
138  * and commands that are currently executing.  This means that an 
139  * unlimited number of commands may be queued, letting 
140  * more commands propagate from the higher driver levels giving higher 
141  * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported, 
142  * allowing multiple commands to propagate all the way to a SCSI-II device 
143  * while a command is already executing.
144  *
145  *
146  * Issues specific to the NCR5380 : 
147  *
148  * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 
149  * piece of hardware that requires you to sit in a loop polling for 
150  * the REQ signal as long as you are connected.  Some devices are 
151  * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 
152  * while doing long seek operations.
153  * 
154  * The workaround for this is to keep track of devices that have
155  * disconnected.  If the device hasn't disconnected, for commands that
156  * should disconnect, we do something like 
157  *
158  * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
159  * 
160  * Some tweaking of N and M needs to be done.  An algorithm based 
161  * on "time to data" would give the best results as long as short time
162  * to datas (ie, on the same track) were considered, however these 
163  * broken devices are the exception rather than the rule and I'd rather
164  * spend my time optimizing for the normal case.
165  *
166  * Architecture :
167  *
168  * At the heart of the design is a coroutine, NCR5380_main,
169  * which is started from a workqueue for each NCR5380 host in the
170  * system.  It attempts to establish I_T_L or I_T_L_Q nexuses by
171  * removing the commands from the issue queue and calling
172  * NCR5380_select() if a nexus is not established. 
173  *
174  * Once a nexus is established, the NCR5380_information_transfer()
175  * phase goes through the various phases as instructed by the target.
176  * if the target goes into MSG IN and sends a DISCONNECT message,
177  * the command structure is placed into the per instance disconnected
178  * queue, and NCR5380_main tries to find more work.  If the target is 
179  * idle for too long, the system will try to sleep.
180  *
181  * If a command has disconnected, eventually an interrupt will trigger,
182  * calling NCR5380_intr()  which will in turn call NCR5380_reselect
183  * to reestablish a nexus.  This will run main if necessary.
184  *
185  * On command termination, the done function will be called as 
186  * appropriate.
187  *
188  * SCSI pointers are maintained in the SCp field of SCSI command 
189  * structures, being initialized after the command is connected
190  * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
191  * Note that in violation of the standard, an implicit SAVE POINTERS operation
192  * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
193  */
194
195 /*
196  * Using this file :
197  * This file a skeleton Linux SCSI driver for the NCR 5380 series
198  * of chips.  To use it, you write an architecture specific functions 
199  * and macros and include this file in your driver.
200  *
201  * These macros control options : 
202  * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be 
203  *      defined.
204  * 
205  * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
206  *      for commands that return with a CHECK CONDITION status. 
207  *
208  * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
209  *      transceivers. 
210  *
211  * DONT_USE_INTR - if defined, never use interrupts, even if we probe or
212  *      override-configure an IRQ.
213  *
214  * LIMIT_TRANSFERSIZE - if defined, limit the pseudo-dma transfers to 512
215  *      bytes at a time.  Since interrupts are disabled by default during
216  *      these transfers, we might need this to give reasonable interrupt
217  *      service time if the transfer size gets too large.
218  *
219  * LINKED - if defined, linked commands are supported.
220  *
221  * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
222  *
223  * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
224  *
225  * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't
226  *      rely on phase mismatch and EOP interrupts to determine end 
227  *      of phase.
228  *
229  * UNSAFE - leave interrupts enabled during pseudo-DMA transfers.  You
230  *          only really want to use this if you're having a problem with
231  *          dropped characters during high speed communications, and even
232  *          then, you're going to be better off twiddling with transfersize
233  *          in the high level code.
234  *
235  * Defaults for these will be provided although the user may want to adjust 
236  * these to allocate CPU resources to the SCSI driver or "real" code.
237  * 
238  * USLEEP_SLEEP - amount of time, in jiffies, to sleep
239  *
240  * USLEEP_POLL - amount of time, in jiffies, to poll
241  *
242  * These macros MUST be defined :
243  * NCR5380_local_declare() - declare any local variables needed for your
244  *      transfer routines.
245  *
246  * NCR5380_setup(instance) - initialize any local variables needed from a given
247  *      instance of the host adapter for NCR5380_{read,write,pread,pwrite}
248  * 
249  * NCR5380_read(register)  - read from the specified register
250  *
251  * NCR5380_write(register, value) - write to the specific register 
252  *
253  * NCR5380_implementation_fields  - additional fields needed for this 
254  *      specific implementation of the NCR5380
255  *
256  * Either real DMA *or* pseudo DMA may be implemented
257  * REAL functions : 
258  * NCR5380_REAL_DMA should be defined if real DMA is to be used.
259  * Note that the DMA setup functions should return the number of bytes 
260  *      that they were able to program the controller for.
261  *
262  * Also note that generic i386/PC versions of these macros are 
263  *      available as NCR5380_i386_dma_write_setup,
264  *      NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
265  *
266  * NCR5380_dma_write_setup(instance, src, count) - initialize
267  * NCR5380_dma_read_setup(instance, dst, count) - initialize
268  * NCR5380_dma_residual(instance); - residual count
269  *
270  * PSEUDO functions :
271  * NCR5380_pwrite(instance, src, count)
272  * NCR5380_pread(instance, dst, count);
273  *
274  * The generic driver is initialized by calling NCR5380_init(instance),
275  * after setting the appropriate host specific fields and ID.  If the 
276  * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
277  * possible) function may be used.
278  */
279
280 static int do_abort(struct Scsi_Host *host);
281 static void do_reset(struct Scsi_Host *host);
282
283 /*
284  *      initialize_SCp          -       init the scsi pointer field
285  *      @cmd: command block to set up
286  *
287  *      Set up the internal fields in the SCSI command.
288  */
289
290 static __inline__ void initialize_SCp(Scsi_Cmnd * cmd)
291 {
292         /* 
293          * Initialize the Scsi Pointer field so that all of the commands in the 
294          * various queues are valid.
295          */
296
297         if (cmd->use_sg) {
298                 cmd->SCp.buffer = (struct scatterlist *) cmd->buffer;
299                 cmd->SCp.buffers_residual = cmd->use_sg - 1;
300                 cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+
301                                cmd->SCp.buffer->offset;
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 = (char *) cmd->request_buffer;
307                 cmd->SCp.this_residual = cmd->request_bufflen;
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                         yield();
350                 else
351                         cpu_relax();
352         }
353         return -ETIMEDOUT;
354 }
355
356 static struct {
357         unsigned char value;
358         const char *name;
359 } phases[] = {
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 weather 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                                         struct pt_regs *regs)
562 {
563         probe_irq = irq;
564         return IRQ_HANDLED;
565 }
566
567 /**
568  *      NCR5380_probe_irq       -       find the IRQ of an NCR5380
569  *      @instance: NCR5380 controller
570  *      @possible: bitmask of ISA IRQ lines
571  *
572  *      Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ
573  *      and then looking to see what interrupt actually turned up.
574  *
575  *      Locks: none, irqs must be enabled on entry
576  */
577
578 static int __init NCR5380_probe_irq(struct Scsi_Host *instance, 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, SA_INTERRUPT, "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         {
610                 set_current_state(TASK_UNINTERRUPTIBLE);
611                 schedule_timeout(1);
612         }
613         
614         NCR5380_write(SELECT_ENABLE_REG, 0);
615         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
616
617         for (i = 0, mask = 1; i < 16; ++i, mask <<= 1)
618                 if (trying_irqs & mask)
619                         free_irq(i, NULL);
620
621         return probe_irq;
622 }
623
624 /**
625  *      NCR58380_print_options  -       show options
626  *      @instance: unused for now
627  *
628  *      Called by probe code indicating the NCR5380 driver options that 
629  *      were selected. At some point this will switch to runtime options
630  *      read from the adapter in question
631  *
632  *      Locks: none
633  */
634
635 static void __init NCR5380_print_options(struct Scsi_Host *instance)
636 {
637         printk(" generic options"
638 #ifdef AUTOPROBE_IRQ
639                " AUTOPROBE_IRQ"
640 #endif
641 #ifdef AUTOSENSE
642                " AUTOSENSE"
643 #endif
644 #ifdef DIFFERENTIAL
645                " DIFFERENTIAL"
646 #endif
647 #ifdef REAL_DMA
648                " REAL DMA"
649 #endif
650 #ifdef REAL_DMA_POLL
651                " REAL DMA POLL"
652 #endif
653 #ifdef PARITY
654                " PARITY"
655 #endif
656 #ifdef PSEUDO_DMA
657                " PSEUDO DMA"
658 #endif
659 #ifdef UNSAFE
660                " UNSAFE "
661 #endif
662             );
663         printk(" USLEEP, USLEEP_POLL=%d USLEEP_SLEEP=%d", USLEEP_POLL, USLEEP_SLEEP);
664         printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
665         if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) {
666                 printk(" ncr53c400 release=%d", NCR53C400_PUBLIC_RELEASE);
667         }
668 }
669
670 /**
671  *      NCR5380_print_status    -       dump controller info
672  *      @instance: controller to dump
673  *
674  *      Print commands in the various queues, called from NCR5380_abort 
675  *      and NCR5380_debug to aid debugging.
676  *
677  *      Locks: called functions disable irqs
678  */
679
680 static void NCR5380_print_status(struct Scsi_Host *instance)
681 {
682         NCR5380_dprint(NDEBUG_ANY, instance);
683         NCR5380_dprint_phase(NDEBUG_ANY, instance);
684 }
685
686 /******************************************/
687 /*
688  * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
689  *
690  * *buffer: I/O buffer
691  * **start: if inout == FALSE pointer into buffer where user read should start
692  * offset: current offset
693  * length: length of buffer
694  * hostno: Scsi_Host host_no
695  * inout: TRUE - user is writing; FALSE - user is reading
696  *
697  * Return the number of bytes read from or written
698  */
699
700 #undef SPRINTF
701 #define SPRINTF(args...) do { if(pos < buffer + length-80) pos += sprintf(pos, ## args); } while(0)
702 static
703 char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length);
704 static
705 char *lprint_command(unsigned char *cmd, char *pos, char *buffer, int len);
706 static
707 char *lprint_opcode(int opcode, char *pos, char *buffer, int length);
708
709 static
710 int NCR5380_proc_info(struct Scsi_Host *instance, char *buffer, char **start, off_t offset, int length, int inout)
711 {
712         char *pos = buffer;
713         struct NCR5380_hostdata *hostdata;
714         Scsi_Cmnd *ptr;
715
716         hostdata = (struct NCR5380_hostdata *) instance->hostdata;
717
718         if (inout) {            /* Has data been written to the file ? */
719 #ifdef DTC_PUBLIC_RELEASE
720                 dtc_wmaxi = dtc_maxi = 0;
721 #endif
722 #ifdef PAS16_PUBLIC_RELEASE
723                 pas_wmaxi = pas_maxi = 0;
724 #endif
725                 return (-ENOSYS);       /* Currently this is a no-op */
726         }
727         SPRINTF("NCR5380 core release=%d.   ", NCR5380_PUBLIC_RELEASE);
728         if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400)
729                 SPRINTF("ncr53c400 release=%d.  ", NCR53C400_PUBLIC_RELEASE);
730 #ifdef DTC_PUBLIC_RELEASE
731         SPRINTF("DTC 3180/3280 release %d", DTC_PUBLIC_RELEASE);
732 #endif
733 #ifdef T128_PUBLIC_RELEASE
734         SPRINTF("T128 release %d", T128_PUBLIC_RELEASE);
735 #endif
736 #ifdef GENERIC_NCR5380_PUBLIC_RELEASE
737         SPRINTF("Generic5380 release %d", GENERIC_NCR5380_PUBLIC_RELEASE);
738 #endif
739 #ifdef PAS16_PUBLIC_RELEASE
740         SPRINTF("PAS16 release=%d", PAS16_PUBLIC_RELEASE);
741 #endif
742
743         SPRINTF("\nBase Addr: 0x%05lX    ", (long) instance->base);
744         SPRINTF("io_port: %04x      ", (int) instance->io_port);
745         if (instance->irq == SCSI_IRQ_NONE)
746                 SPRINTF("IRQ: None.\n");
747         else
748                 SPRINTF("IRQ: %d.\n", instance->irq);
749
750 #ifdef DTC_PUBLIC_RELEASE
751         SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", dtc_wmaxi, dtc_maxi);
752 #endif
753 #ifdef PAS16_PUBLIC_RELEASE
754         SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", pas_wmaxi, pas_maxi);
755 #endif
756         spin_lock_irq(instance->host_lock);
757         if (!hostdata->connected)
758                 SPRINTF("scsi%d: no currently connected command\n", instance->host_no);
759         else
760                 pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, pos, buffer, length);
761         SPRINTF("scsi%d: issue_queue\n", instance->host_no);
762         for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
763                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
764
765         SPRINTF("scsi%d: disconnected_queue\n", instance->host_no);
766         for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
767                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
768         spin_unlock_irq(instance->host_lock);
769         
770         *start = buffer;
771         if (pos - buffer < offset)
772                 return 0;
773         else if (pos - buffer - offset < length)
774                 return pos - buffer - offset;
775         return length;
776 }
777
778 static char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length)
779 {
780         SPRINTF("scsi%d : destination target %d, lun %d\n", cmd->device->host->host_no, cmd->device->id, cmd->device->lun);
781         SPRINTF("        command = ");
782         pos = lprint_command(cmd->cmnd, pos, buffer, length);
783         return (pos);
784 }
785
786 static char *lprint_command(unsigned char *command, char *pos, char *buffer, int length)
787 {
788         int i, s;
789         pos = lprint_opcode(command[0], pos, buffer, length);
790         for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
791                 SPRINTF("%02x ", command[i]);
792         SPRINTF("\n");
793         return (pos);
794 }
795
796 static char *lprint_opcode(int opcode, char *pos, char *buffer, int length)
797 {
798         SPRINTF("%2d (0x%02x)", opcode, opcode);
799         return (pos);
800 }
801
802
803 /**
804  *      NCR5380_init    -       initialise an NCR5380
805  *      @instance: adapter to configure
806  *      @flags: control flags
807  *
808  *      Initializes *instance and corresponding 5380 chip,
809  *      with flags OR'd into the initial flags value.
810  *
811  *      Notes : I assume that the host, hostno, and id bits have been
812  *      set correctly.  I don't care about the irq and other fields. 
813  *
814  *      Returns 0 for success
815  *
816  *      Locks: interrupts must be enabled when we are called 
817  */
818
819 static int __devinit NCR5380_init(struct Scsi_Host *instance, int flags)
820 {
821         NCR5380_local_declare();
822         int i, pass;
823         unsigned long timeout;
824         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
825
826         if(in_interrupt())
827                 printk(KERN_ERR "NCR5380_init called with interrupts off!\n");
828         /* 
829          * On NCR53C400 boards, NCR5380 registers are mapped 8 past 
830          * the base address.
831          */
832
833 #ifdef NCR53C400
834         if (flags & FLAG_NCR53C400)
835                 instance->NCR5380_instance_name += NCR53C400_address_adjust;
836 #endif
837
838         NCR5380_setup(instance);
839
840         hostdata->aborted = 0;
841         hostdata->id_mask = 1 << instance->this_id;
842         for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
843                 if (i > hostdata->id_mask)
844                         hostdata->id_higher_mask |= i;
845         for (i = 0; i < 8; ++i)
846                 hostdata->busy[i] = 0;
847 #ifdef REAL_DMA
848         hostdata->dmalen = 0;
849 #endif
850         hostdata->targets_present = 0;
851         hostdata->connected = NULL;
852         hostdata->issue_queue = NULL;
853         hostdata->disconnected_queue = NULL;
854         
855         INIT_WORK(&hostdata->coroutine, NCR5380_main, hostdata);
856         
857 #ifdef NCR5380_STATS
858         for (i = 0; i < 8; ++i) {
859                 hostdata->time_read[i] = 0;
860                 hostdata->time_write[i] = 0;
861                 hostdata->bytes_read[i] = 0;
862                 hostdata->bytes_write[i] = 0;
863         }
864         hostdata->timebase = 0;
865         hostdata->pendingw = 0;
866         hostdata->pendingr = 0;
867 #endif
868
869         /* The CHECK code seems to break the 53C400. Will check it later maybe */
870         if (flags & FLAG_NCR53C400)
871                 hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags;
872         else
873                 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags;
874
875         hostdata->host = instance;
876         hostdata->time_expires = 0;
877
878 #ifndef AUTOSENSE
879         if ((instance->cmd_per_lun > 1) || instance->can_queue > 1)
880                     printk(KERN_WARNING "scsi%d : WARNING : support for multiple outstanding commands enabled\n" "         without AUTOSENSE option, contingent allegiance conditions may\n"
881                            "         be incorrectly cleared.\n", instance->host_no);
882 #endif                          /* def AUTOSENSE */
883
884         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
885         NCR5380_write(MODE_REG, MR_BASE);
886         NCR5380_write(TARGET_COMMAND_REG, 0);
887         NCR5380_write(SELECT_ENABLE_REG, 0);
888
889 #ifdef NCR53C400
890         if (hostdata->flags & FLAG_NCR53C400) {
891                 NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE);
892         }
893 #endif
894
895         /* 
896          * Detect and correct bus wedge problems.
897          *
898          * If the system crashed, it may have crashed in a state 
899          * where a SCSI command was still executing, and the 
900          * SCSI bus is not in a BUS FREE STATE.
901          *
902          * If this is the case, we'll try to abort the currently
903          * established nexus which we know nothing about, and that
904          * failing, do a hard reset of the SCSI bus 
905          */
906
907         for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
908                 switch (pass) {
909                 case 1:
910                 case 3:
911                 case 5:
912                         printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no);
913                         timeout = jiffies + 5 * HZ;
914                         NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ);
915                         break;
916                 case 2:
917                         printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no);
918                         do_abort(instance);
919                         break;
920                 case 4:
921                         printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no);
922                         do_reset(instance);
923                         break;
924                 case 6:
925                         printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no);
926                         return -ENXIO;
927                 }
928         }
929         return 0;
930 }
931
932 /**
933  *      NCR5380_exit    -       remove an NCR5380
934  *      @instance: adapter to remove
935  */
936
937 static void __devexit NCR5380_exit(struct Scsi_Host *instance)
938 {
939         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
940
941         cancel_delayed_work(&hostdata->coroutine);
942         flush_scheduled_work();
943 }
944
945 /**
946  *      NCR5380_queue_command           -       queue a command
947  *      @cmd: SCSI command
948  *      @done: completion handler
949  *
950  *      cmd is added to the per instance issue_queue, with minor 
951  *      twiddling done to the host specific fields of cmd.  If the 
952  *      main coroutine is not running, it is restarted.
953  *
954  *      Locks: host lock taken by caller
955  */
956
957 static int NCR5380_queue_command(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *)) 
958 {
959         struct Scsi_Host *instance = cmd->device->host;
960         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
961         Scsi_Cmnd *tmp;
962
963 #if (NDEBUG & NDEBUG_NO_WRITE)
964         switch (cmd->cmnd[0]) {
965         case WRITE_6:
966         case WRITE_10:
967                 printk("scsi%d : WRITE attempted with NO_WRITE debugging flag set\n", instance->host_no);
968                 cmd->result = (DID_ERROR << 16);
969                 done(cmd);
970                 return 0;
971         }
972 #endif                          /* (NDEBUG & NDEBUG_NO_WRITE) */
973
974 #ifdef NCR5380_STATS
975         switch (cmd->cmnd[0]) {
976                 case WRITE:
977                 case WRITE_6:
978                 case WRITE_10:
979                         hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
980                         hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen;
981                         hostdata->pendingw++;
982                         break;
983                 case READ:
984                 case READ_6:
985                 case READ_10:
986                         hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
987                         hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen;
988                         hostdata->pendingr++;
989                         break;
990         }
991 #endif
992
993         /* 
994          * We use the host_scribble field as a pointer to the next command  
995          * in a queue 
996          */
997
998         cmd->host_scribble = NULL;
999         cmd->scsi_done = done;
1000         cmd->result = 0;
1001
1002         /* 
1003          * Insert the cmd into the issue queue. Note that REQUEST SENSE 
1004          * commands are added to the head of the queue since any command will
1005          * clear the contingent allegiance condition that exists and the 
1006          * sense data is only guaranteed to be valid while the condition exists.
1007          */
1008
1009         if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
1010                 LIST(cmd, hostdata->issue_queue);
1011                 cmd->host_scribble = (unsigned char *) hostdata->issue_queue;
1012                 hostdata->issue_queue = cmd;
1013         } else {
1014                 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp->host_scribble; tmp = (Scsi_Cmnd *) tmp->host_scribble);
1015                 LIST(cmd, tmp);
1016                 tmp->host_scribble = (unsigned char *) cmd;
1017         }
1018         dprintk(NDEBUG_QUEUES, ("scsi%d : command added to %s of queue\n", instance->host_no, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"));
1019
1020         /* Run the coroutine if it isn't already running. */
1021         /* Kick off command processing */
1022         schedule_work(&hostdata->coroutine);
1023         return 0;
1024 }
1025
1026
1027 /**
1028  *      NCR5380_main    -       NCR state machines
1029  *
1030  *      NCR5380_main is a coroutine that runs as long as more work can 
1031  *      be done on the NCR5380 host adapters in a system.  Both 
1032  *      NCR5380_queue_command() and NCR5380_intr() will try to start it 
1033  *      in case it is not running.
1034  * 
1035  *      Locks: called as its own thread with no locks held. Takes the
1036  *      host lock and called routines may take the isa dma lock.
1037  */
1038
1039 static void NCR5380_main(void *p)
1040 {
1041         struct NCR5380_hostdata *hostdata = p;
1042         struct Scsi_Host *instance = hostdata->host;
1043         Scsi_Cmnd *tmp, *prev;
1044         int done;
1045         
1046         spin_lock_irq(instance->host_lock);
1047         do {
1048                 /* Lock held here */
1049                 done = 1;
1050                 if (!hostdata->connected && !hostdata->selecting) {
1051                         dprintk(NDEBUG_MAIN, ("scsi%d : not connected\n", instance->host_no));
1052                         /*
1053                          * Search through the issue_queue for a command destined
1054                          * for a target that's not busy.
1055                          */
1056                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble) 
1057                         {
1058                                 if (prev != tmp)
1059                                         dprintk(NDEBUG_LISTS, ("MAIN tmp=%p   target=%d   busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun));
1060                                 /*  When we find one, remove it from the issue queue. */
1061                                 if (!(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))) {
1062                                         if (prev) {
1063                                                 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
1064                                                 prev->host_scribble = tmp->host_scribble;
1065                                         } else {
1066                                                 REMOVE(-1, hostdata->issue_queue, tmp, tmp->host_scribble);
1067                                                 hostdata->issue_queue = (Scsi_Cmnd *) tmp->host_scribble;
1068                                         }
1069                                         tmp->host_scribble = NULL;
1070
1071                                         /* 
1072                                          * Attempt to establish an I_T_L nexus here. 
1073                                          * On success, instance->hostdata->connected is set.
1074                                          * On failure, we must add the command back to the
1075                                          *   issue queue so we can keep trying. 
1076                                          */
1077                                         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));
1078         
1079                                         /*
1080                                          * A successful selection is defined as one that 
1081                                          * leaves us with the command connected and 
1082                                          * in hostdata->connected, OR has terminated the
1083                                          * command.
1084                                          *
1085                                          * With successful commands, we fall through
1086                                          * and see if we can do an information transfer,
1087                                          * with failures we will restart.
1088                                          */
1089                                         hostdata->selecting = NULL;
1090                                         /* RvC: have to preset this to indicate a new command is being performed */
1091
1092                                         if (!NCR5380_select(instance, tmp,
1093                                                             /* 
1094                                                              * REQUEST SENSE commands are issued without tagged
1095                                                              * queueing, even on SCSI-II devices because the 
1096                                                              * contingent allegiance condition exists for the 
1097                                                              * entire unit.
1098                                                              */
1099                                                             (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1100                                                 break;
1101                                         } else {
1102                                                 LIST(tmp, hostdata->issue_queue);
1103                                                 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1104                                                 hostdata->issue_queue = tmp;
1105                                                 done = 0;
1106                                                 dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main(): select() failed, returned to issue_queue\n", instance->host_no));
1107                                         }
1108                                         /* lock held here still */
1109                                 }       /* if target/lun is not busy */
1110                         }       /* for */
1111                         /* exited locked */
1112                 }       /* if (!hostdata->connected) */
1113                 if (hostdata->selecting) {
1114                         tmp = (Scsi_Cmnd *) hostdata->selecting;
1115                         /* Selection will drop and retake the lock */
1116                         if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1117                                 /* Ok ?? */
1118                         } else {
1119                                 /* RvC: device failed, so we wait a long time
1120                                    this is needed for Mustek scanners, that
1121                                    do not respond to commands immediately
1122                                    after a scan */
1123                                 printk(KERN_DEBUG "scsi%d: device %d did not respond in time\n", instance->host_no, tmp->device->id);
1124                                 LIST(tmp, hostdata->issue_queue);
1125                                 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1126                                 hostdata->issue_queue = tmp;
1127                                 NCR5380_set_timer(hostdata, USLEEP_WAITLONG);
1128                         }
1129                 }       /* if hostdata->selecting */
1130                 if (hostdata->connected
1131 #ifdef REAL_DMA
1132                     && !hostdata->dmalen
1133 #endif
1134                     && (!hostdata->time_expires || time_before_eq(hostdata->time_expires, jiffies))
1135                     ) {
1136                         dprintk(NDEBUG_MAIN, ("scsi%d : main() : performing information transfer\n", instance->host_no));
1137                         NCR5380_information_transfer(instance);
1138                         dprintk(NDEBUG_MAIN, ("scsi%d : main() : done set false\n", instance->host_no));
1139                         done = 0;
1140                 } else
1141                         break;
1142         } while (!done);
1143         
1144         spin_unlock_irq(instance->host_lock);
1145 }
1146
1147 #ifndef DONT_USE_INTR
1148
1149 /**
1150  *      NCR5380_intr    -       generic NCR5380 irq handler
1151  *      @irq: interrupt number
1152  *      @dev_id: device info
1153  *      @regs: registers (unused)
1154  *
1155  *      Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1156  *      from the disconnected queue, and restarting NCR5380_main() 
1157  *      as required.
1158  *
1159  *      Locks: takes the needed instance locks
1160  */
1161
1162 static irqreturn_t NCR5380_intr(int irq, void *dev_id, struct pt_regs *regs) 
1163 {
1164         NCR5380_local_declare();
1165         struct Scsi_Host *instance = (struct Scsi_Host *)dev_id;
1166         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1167         int done;
1168         unsigned char basr;
1169         unsigned long flags;
1170
1171         dprintk(NDEBUG_INTR, ("scsi : NCR5380 irq %d triggered\n", irq));
1172
1173         do {
1174                 done = 1;
1175                 spin_lock_irqsave(instance->host_lock, flags);
1176                 /* Look for pending interrupts */
1177                 NCR5380_setup(instance);
1178                 basr = NCR5380_read(BUS_AND_STATUS_REG);
1179                 /* XXX dispatch to appropriate routine if found and done=0 */
1180                 if (basr & BASR_IRQ) {
1181                         NCR5380_dprint(NDEBUG_INTR, instance);
1182                         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1183                                 done = 0;
1184                                 dprintk(NDEBUG_INTR, ("scsi%d : SEL interrupt\n", instance->host_no));
1185                                 NCR5380_reselect(instance);
1186                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1187                         } else if (basr & BASR_PARITY_ERROR) {
1188                                 dprintk(NDEBUG_INTR, ("scsi%d : PARITY interrupt\n", instance->host_no));
1189                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1190                         } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1191                                 dprintk(NDEBUG_INTR, ("scsi%d : RESET interrupt\n", instance->host_no));
1192                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1193                         } else {
1194 #if defined(REAL_DMA)
1195                                 /*
1196                                  * We should only get PHASE MISMATCH and EOP interrupts
1197                                  * if we have DMA enabled, so do a sanity check based on
1198                                  * the current setting of the MODE register.
1199                                  */
1200
1201                                 if ((NCR5380_read(MODE_REG) & MR_DMA) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) {
1202                                         int transfered;
1203
1204                                         if (!hostdata->connected)
1205                                                 panic("scsi%d : received end of DMA interrupt with no connected cmd\n", instance->hostno);
1206
1207                                         transfered = (hostdata->dmalen - NCR5380_dma_residual(instance));
1208                                         hostdata->connected->SCp.this_residual -= transferred;
1209                                         hostdata->connected->SCp.ptr += transferred;
1210                                         hostdata->dmalen = 0;
1211
1212                                         (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1213                                                         
1214                                         /* FIXME: we need to poll briefly then defer a workqueue task ! */
1215                                         NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2*HZ);
1216
1217                                         NCR5380_write(MODE_REG, MR_BASE);
1218                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1219                                 }
1220 #else
1221                                 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)));
1222                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1223 #endif
1224                         }
1225                 }       /* if BASR_IRQ */
1226                 spin_unlock_irqrestore(instance->host_lock, flags);
1227                 if(!done)
1228                         schedule_work(&hostdata->coroutine);
1229         } while (!done);
1230         return IRQ_HANDLED;
1231 }
1232
1233 #endif 
1234
1235 /**
1236  *      collect_stats           -       collect stats on a scsi command
1237  *      @hostdata: adapter 
1238  *      @cmd: command being issued
1239  *
1240  *      Update the statistical data by parsing the command in question
1241  */
1242  
1243 static void collect_stats(struct NCR5380_hostdata *hostdata, Scsi_Cmnd * cmd) 
1244 {
1245 #ifdef NCR5380_STATS
1246         switch (cmd->cmnd[0]) {
1247         case WRITE:
1248         case WRITE_6:
1249         case WRITE_10:
1250                 hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase);
1251                 hostdata->pendingw--;
1252                 break;
1253         case READ:
1254         case READ_6:
1255         case READ_10:
1256                 hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase);
1257                 hostdata->pendingr--;
1258                 break;
1259         }
1260 #endif
1261 }
1262
1263
1264 /* 
1265  * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, 
1266  *      int tag);
1267  *
1268  * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1269  *      including ARBITRATION, SELECTION, and initial message out for 
1270  *      IDENTIFY and queue messages. 
1271  *
1272  * Inputs : instance - instantiation of the 5380 driver on which this 
1273  *      target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for 
1274  *      new tag, TAG_NONE for untagged queueing, otherwise set to the tag for 
1275  *      the command that is presently connected.
1276  * 
1277  * Returns : -1 if selection could not execute for some reason,
1278  *      0 if selection succeeded or failed because the target 
1279  *      did not respond.
1280  *
1281  * Side effects : 
1282  *      If bus busy, arbitration failed, etc, NCR5380_select() will exit 
1283  *              with registers as they should have been on entry - ie
1284  *              SELECT_ENABLE will be set appropriately, the NCR5380
1285  *              will cease to drive any SCSI bus signals.
1286  *
1287  *      If successful : I_T_L or I_T_L_Q nexus will be established, 
1288  *              instance->connected will be set to cmd.  
1289  *              SELECT interrupt will be disabled.
1290  *
1291  *      If failed (no target) : cmd->scsi_done() will be called, and the 
1292  *              cmd->result host byte set to DID_BAD_TARGET.
1293  *
1294  *      Locks: caller holds hostdata lock in IRQ mode
1295  */
1296  
1297 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag) 
1298 {
1299         NCR5380_local_declare();
1300         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1301         unsigned char tmp[3], phase;
1302         unsigned char *data;
1303         int len;
1304         unsigned long timeout;
1305         unsigned char value;
1306         int err;
1307         NCR5380_setup(instance);
1308
1309         if (hostdata->selecting)
1310                 goto part2;
1311
1312         hostdata->restart_select = 0;
1313
1314         NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1315         dprintk(NDEBUG_ARBITRATION, ("scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id));
1316
1317         /* 
1318          * Set the phase bits to 0, otherwise the NCR5380 won't drive the 
1319          * data bus during SELECTION.
1320          */
1321
1322         NCR5380_write(TARGET_COMMAND_REG, 0);
1323
1324         /* 
1325          * Start arbitration.
1326          */
1327
1328         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1329         NCR5380_write(MODE_REG, MR_ARBITRATE);
1330
1331
1332         /* We can be relaxed here, interrupts are on, we are
1333            in workqueue context, the birds are singing in the trees */
1334         spin_unlock_irq(instance->host_lock);
1335         err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ);
1336         spin_lock_irq(instance->host_lock);
1337         if (err < 0) {
1338                 printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__);
1339                 NCR5380_write(MODE_REG, MR_BASE);
1340                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1341                 goto failed;
1342         }
1343
1344         dprintk(NDEBUG_ARBITRATION, ("scsi%d : arbitration complete\n", instance->host_no));
1345
1346         /* 
1347          * The arbitration delay is 2.2us, but this is a minimum and there is 
1348          * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1349          * the integral nature of udelay().
1350          *
1351          */
1352
1353         udelay(3);
1354
1355         /* Check for lost arbitration */
1356         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)) {
1357                 NCR5380_write(MODE_REG, MR_BASE);
1358                 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no));
1359                 goto failed;
1360         }
1361         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL);
1362
1363         if (!(hostdata->flags & FLAG_DTC3181E) &&
1364             /* RvC: DTC3181E has some trouble with this
1365              *      so we simply removed it. Seems to work with
1366              *      only Mustek scanner attached
1367              */
1368             (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1369                 NCR5380_write(MODE_REG, MR_BASE);
1370                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1371                 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no));
1372                 goto failed;
1373         }
1374         /* 
1375          * Again, bus clear + bus settle time is 1.2us, however, this is 
1376          * a minimum so we'll udelay ceil(1.2)
1377          */
1378
1379         udelay(2);
1380
1381         dprintk(NDEBUG_ARBITRATION, ("scsi%d : won arbitration\n", instance->host_no));
1382
1383         /* 
1384          * Now that we have won arbitration, start Selection process, asserting 
1385          * the host and target ID's on the SCSI bus.
1386          */
1387
1388         NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id)));
1389
1390         /* 
1391          * Raise ATN while SEL is true before BSY goes false from arbitration,
1392          * since this is the only way to guarantee that we'll get a MESSAGE OUT
1393          * phase immediately after selection.
1394          */
1395
1396         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1397         NCR5380_write(MODE_REG, MR_BASE);
1398
1399         /* 
1400          * Reselect interrupts must be turned off prior to the dropping of BSY,
1401          * otherwise we will trigger an interrupt.
1402          */
1403         NCR5380_write(SELECT_ENABLE_REG, 0);
1404
1405         /*
1406          * The initiator shall then wait at least two deskew delays and release 
1407          * the BSY signal.
1408          */
1409         udelay(1);              /* wingel -- wait two bus deskew delay >2*45ns */
1410
1411         /* Reset BSY */
1412         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1413
1414         /* 
1415          * Something weird happens when we cease to drive BSY - looks
1416          * like the board/chip is letting us do another read before the 
1417          * appropriate propagation delay has expired, and we're confusing
1418          * a BSY signal from ourselves as the target's response to SELECTION.
1419          *
1420          * A small delay (the 'C++' frontend breaks the pipeline with an
1421          * unnecessary jump, making it work on my 386-33/Trantor T128, the
1422          * tighter 'C' code breaks and requires this) solves the problem - 
1423          * the 1 us delay is arbitrary, and only used because this delay will 
1424          * be the same on other platforms and since it works here, it should 
1425          * work there.
1426          *
1427          * wingel suggests that this could be due to failing to wait
1428          * one deskew delay.
1429          */
1430
1431         udelay(1);
1432
1433         dprintk(NDEBUG_SELECTION, ("scsi%d : selecting target %d\n", instance->host_no, cmd->device->id));
1434
1435         /* 
1436          * The SCSI specification calls for a 250 ms timeout for the actual 
1437          * selection.
1438          */
1439
1440         timeout = jiffies + (250 * HZ / 1000);
1441
1442         /* 
1443          * XXX very interesting - we're seeing a bounce where the BSY we 
1444          * asserted is being reflected / still asserted (propagation delay?)
1445          * and it's detecting as true.  Sigh.
1446          */
1447
1448         hostdata->select_time = 0;      /* we count the clock ticks at which we polled */
1449         hostdata->selecting = cmd;
1450
1451 part2:
1452         /* RvC: here we enter after a sleeping period, or immediately after
1453            execution of part 1
1454            we poll only once ech clock tick */
1455         value = NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO);
1456
1457         if (!value && (hostdata->select_time < HZ/4)) {
1458                 /* RvC: we still must wait for a device response */
1459                 hostdata->select_time++;        /* after 25 ticks the device has failed */
1460                 NCR5380_set_timer(hostdata, 1);
1461                 return 0;       /* RvC: we return here with hostdata->selecting set,
1462                                    to go to sleep */
1463         }
1464
1465         hostdata->selecting = NULL;/* clear this pointer, because we passed the
1466                                            waiting period */
1467         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1468                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1469                 NCR5380_reselect(instance);
1470                 printk("scsi%d : reselection after won arbitration?\n", instance->host_no);
1471                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1472                 return -1;
1473         }
1474         /* 
1475          * No less than two deskew delays after the initiator detects the 
1476          * BSY signal is true, it shall release the SEL signal and may 
1477          * change the DATA BUS.                                     -wingel
1478          */
1479
1480         udelay(1);
1481
1482         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1483
1484         if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1485                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1486                 if (hostdata->targets_present & (1 << cmd->device->id)) {
1487                         printk(KERN_DEBUG "scsi%d : weirdness\n", instance->host_no);
1488                         if (hostdata->restart_select)
1489                                 printk(KERN_DEBUG "\trestart select\n");
1490                         NCR5380_dprint(NDEBUG_SELECTION, instance);
1491                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1492                         return -1;
1493                 }
1494                 cmd->result = DID_BAD_TARGET << 16;
1495                 collect_stats(hostdata, cmd);
1496                 cmd->scsi_done(cmd);
1497                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1498                 dprintk(NDEBUG_SELECTION, ("scsi%d : target did not respond within 250ms\n", instance->host_no));
1499                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1500                 return 0;
1501         }
1502         hostdata->targets_present |= (1 << cmd->device->id);
1503
1504         /*
1505          * Since we followed the SCSI spec, and raised ATN while SEL 
1506          * was true but before BSY was false during selection, the information
1507          * transfer phase should be a MESSAGE OUT phase so that we can send the
1508          * IDENTIFY message.
1509          * 
1510          * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1511          * message (2 bytes) with a tag ID that we increment with every command
1512          * until it wraps back to 0.
1513          *
1514          * XXX - it turns out that there are some broken SCSI-II devices,
1515          *       which claim to support tagged queuing but fail when more than
1516          *       some number of commands are issued at once.
1517          */
1518
1519         /* Wait for start of REQ/ACK handshake */
1520
1521         spin_unlock_irq(instance->host_lock);
1522         err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
1523         spin_lock_irq(instance->host_lock);
1524         
1525         if(err) {
1526                 printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__);
1527                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1528                 goto failed;
1529         }
1530
1531         dprintk(NDEBUG_SELECTION, ("scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id));
1532         tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun);
1533
1534         len = 1;
1535         cmd->tag = 0;
1536
1537         /* Send message(s) */
1538         data = tmp;
1539         phase = PHASE_MSGOUT;
1540         NCR5380_transfer_pio(instance, &phase, &len, &data);
1541         dprintk(NDEBUG_SELECTION, ("scsi%d : nexus established.\n", instance->host_no));
1542         /* XXX need to handle errors here */
1543         hostdata->connected = cmd;
1544         hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1545
1546         if (cmd->SCp.ptr != (char *)cmd->sense_buffer) {
1547                 initialize_SCp(cmd);
1548         }
1549
1550         return 0;
1551
1552         /* Selection failed */
1553 failed:
1554         return -1;
1555
1556 }
1557
1558 /* 
1559  * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, 
1560  *      unsigned char *phase, int *count, unsigned char **data)
1561  *
1562  * Purpose : transfers data in given phase using polled I/O
1563  *
1564  * Inputs : instance - instance of driver, *phase - pointer to 
1565  *      what phase is expected, *count - pointer to number of 
1566  *      bytes to transfer, **data - pointer to data pointer.
1567  * 
1568  * Returns : -1 when different phase is entered without transferring
1569  *      maximum number of bytes, 0 if all bytes or transfered or exit
1570  *      is in same phase.
1571  *
1572  *      Also, *phase, *count, *data are modified in place.
1573  *
1574  * XXX Note : handling for bus free may be useful.
1575  */
1576
1577 /*
1578  * Note : this code is not as quick as it could be, however it 
1579  * IS 100% reliable, and for the actual data transfer where speed
1580  * counts, we will always do a pseudo DMA or DMA transfer.
1581  */
1582
1583 static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1584         NCR5380_local_declare();
1585         unsigned char p = *phase, tmp;
1586         int c = *count;
1587         unsigned char *d = *data;
1588         /*
1589          *      RvC: some administrative data to process polling time
1590          */
1591         int break_allowed = 0;
1592         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1593         NCR5380_setup(instance);
1594
1595         if (!(p & SR_IO))
1596                 dprintk(NDEBUG_PIO, ("scsi%d : pio write %d bytes\n", instance->host_no, c));
1597         else
1598                 dprintk(NDEBUG_PIO, ("scsi%d : pio read %d bytes\n", instance->host_no, c));
1599
1600         /* 
1601          * The NCR5380 chip will only drive the SCSI bus when the 
1602          * phase specified in the appropriate bits of the TARGET COMMAND
1603          * REGISTER match the STATUS REGISTER
1604          */
1605
1606          NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1607
1608         /* RvC: don't know if this is necessary, but other SCSI I/O is short
1609          *      so breaks are not necessary there
1610          */
1611         if ((p == PHASE_DATAIN) || (p == PHASE_DATAOUT)) {
1612                 break_allowed = 1;
1613         }
1614         do {
1615                 /* 
1616                  * Wait for assertion of REQ, after which the phase bits will be 
1617                  * valid 
1618                  */
1619
1620                 /* RvC: we simply poll once, after that we stop temporarily
1621                  *      and let the device buffer fill up
1622                  *      if breaking is not allowed, we keep polling as long as needed
1623                  */
1624
1625                 /* FIXME */
1626                 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ) && !break_allowed);
1627                 if (!(tmp & SR_REQ)) {
1628                         /* timeout condition */
1629                         NCR5380_set_timer(hostdata, USLEEP_SLEEP);
1630                         break;
1631                 }
1632
1633                 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : REQ detected\n", instance->host_no));
1634
1635                 /* Check for phase mismatch */
1636                 if ((tmp & PHASE_MASK) != p) {
1637                         dprintk(NDEBUG_HANDSHAKE, ("scsi%d : phase mismatch\n", instance->host_no));
1638                         NCR5380_dprint_phase(NDEBUG_HANDSHAKE, instance);
1639                         break;
1640                 }
1641                 /* Do actual transfer from SCSI bus to / from memory */
1642                 if (!(p & SR_IO))
1643                         NCR5380_write(OUTPUT_DATA_REG, *d);
1644                 else
1645                         *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1646
1647                 ++d;
1648
1649                 /* 
1650                  * The SCSI standard suggests that in MSGOUT phase, the initiator
1651                  * should drop ATN on the last byte of the message phase
1652                  * after REQ has been asserted for the handshake but before
1653                  * the initiator raises ACK.
1654                  */
1655
1656                 if (!(p & SR_IO)) {
1657                         if (!((p & SR_MSG) && c > 1)) {
1658                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1659                                 NCR5380_dprint(NDEBUG_PIO, instance);
1660                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1661                         } else {
1662                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1663                                 NCR5380_dprint(NDEBUG_PIO, instance);
1664                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1665                         }
1666                 } else {
1667                         NCR5380_dprint(NDEBUG_PIO, instance);
1668                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1669                 }
1670
1671                 /* FIXME - if this fails bus reset ?? */
1672                 NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 5*HZ);
1673                 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : req false, handshake complete\n", instance->host_no));
1674
1675 /*
1676  * We have several special cases to consider during REQ/ACK handshaking : 
1677  * 1.  We were in MSGOUT phase, and we are on the last byte of the 
1678  *      message.  ATN must be dropped as ACK is dropped.
1679  *
1680  * 2.  We are in a MSGIN phase, and we are on the last byte of the  
1681  *      message.  We must exit with ACK asserted, so that the calling
1682  *      code may raise ATN before dropping ACK to reject the message.
1683  *
1684  * 3.  ACK and ATN are clear and the target may proceed as normal.
1685  */
1686                 if (!(p == PHASE_MSGIN && c == 1)) {
1687                         if (p == PHASE_MSGOUT && c > 1)
1688                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1689                         else
1690                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1691                 }
1692         } while (--c);
1693
1694         dprintk(NDEBUG_PIO, ("scsi%d : residual %d\n", instance->host_no, c));
1695
1696         *count = c;
1697         *data = d;
1698         tmp = NCR5380_read(STATUS_REG);
1699         if (tmp & SR_REQ)
1700                 *phase = tmp & PHASE_MASK;
1701         else
1702                 *phase = PHASE_UNKNOWN;
1703
1704         if (!c || (*phase == p))
1705                 return 0;
1706         else
1707                 return -1;
1708 }
1709
1710 /**
1711  *      do_reset        -       issue a reset command
1712  *      @host: adapter to reset
1713  *
1714  *      Issue a reset sequence to the NCR5380 and try and get the bus
1715  *      back into sane shape.
1716  *
1717  *      Locks: caller holds queue lock
1718  */
1719  
1720 static void do_reset(struct Scsi_Host *host) {
1721         NCR5380_local_declare();
1722         NCR5380_setup(host);
1723
1724         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
1725         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
1726         udelay(25);
1727         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1728 }
1729
1730 /*
1731  * Function : do_abort (Scsi_Host *host)
1732  * 
1733  * Purpose : abort the currently established nexus.  Should only be 
1734  *      called from a routine which can drop into a 
1735  * 
1736  * Returns : 0 on success, -1 on failure.
1737  *
1738  * Locks: queue lock held by caller
1739  *      FIXME: sort this out and get new_eh running
1740  */
1741
1742 static int do_abort(struct Scsi_Host *host) {
1743         NCR5380_local_declare();
1744         unsigned char *msgptr, phase, tmp;
1745         int len;
1746         int rc;
1747         NCR5380_setup(host);
1748
1749
1750         /* Request message out phase */
1751         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1752
1753         /* 
1754          * Wait for the target to indicate a valid phase by asserting 
1755          * REQ.  Once this happens, we'll have either a MSGOUT phase 
1756          * and can immediately send the ABORT message, or we'll have some 
1757          * other phase and will have to source/sink data.
1758          * 
1759          * We really don't care what value was on the bus or what value
1760          * the target sees, so we just handshake.
1761          */
1762
1763         rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, SR_REQ, 60 * HZ);
1764         
1765         if(rc < 0)
1766                 return -1;
1767
1768         tmp = (unsigned char)rc;
1769         
1770         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1771
1772         if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1773                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1774                 rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, 0, 3*HZ);
1775                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1776                 if(rc == -1)
1777                         return -1;
1778         }
1779         tmp = ABORT;
1780         msgptr = &tmp;
1781         len = 1;
1782         phase = PHASE_MSGOUT;
1783         NCR5380_transfer_pio(host, &phase, &len, &msgptr);
1784
1785         /*
1786          * If we got here, and the command completed successfully,
1787          * we're about to go into bus free state.
1788          */
1789
1790         return len ? -1 : 0;
1791 }
1792
1793 #if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL)
1794 /* 
1795  * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, 
1796  *      unsigned char *phase, int *count, unsigned char **data)
1797  *
1798  * Purpose : transfers data in given phase using either real
1799  *      or pseudo DMA.
1800  *
1801  * Inputs : instance - instance of driver, *phase - pointer to 
1802  *      what phase is expected, *count - pointer to number of 
1803  *      bytes to transfer, **data - pointer to data pointer.
1804  * 
1805  * Returns : -1 when different phase is entered without transferring
1806  *      maximum number of bytes, 0 if all bytes or transfered or exit
1807  *      is in same phase.
1808  *
1809  *      Also, *phase, *count, *data are modified in place.
1810  *
1811  *      Locks: io_request lock held by caller
1812  */
1813
1814
1815 static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1816         NCR5380_local_declare();
1817         register int c = *count;
1818         register unsigned char p = *phase;
1819         register unsigned char *d = *data;
1820         unsigned char tmp;
1821         int foo;
1822 #if defined(REAL_DMA_POLL)
1823         int cnt, toPIO;
1824         unsigned char saved_data = 0, overrun = 0, residue;
1825 #endif
1826
1827         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1828
1829         NCR5380_setup(instance);
1830
1831         if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1832                 *phase = tmp;
1833                 return -1;
1834         }
1835 #if defined(REAL_DMA) || defined(REAL_DMA_POLL)
1836 #ifdef READ_OVERRUNS
1837         if (p & SR_IO) {
1838                 c -= 2;
1839         }
1840 #endif
1841         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));
1842         hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c);
1843 #endif
1844
1845         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1846
1847 #ifdef REAL_DMA
1848         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1849 #elif defined(REAL_DMA_POLL)
1850         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1851 #else
1852         /*
1853          * Note : on my sample board, watch-dog timeouts occurred when interrupts
1854          * were not disabled for the duration of a single DMA transfer, from 
1855          * before the setting of DMA mode to after transfer of the last byte.
1856          */
1857
1858 #if defined(PSEUDO_DMA) && defined(UNSAFE)
1859         spin_unlock_irq(instance->host_lock);
1860 #endif
1861         /* KLL May need eop and parity in 53c400 */
1862         if (hostdata->flags & FLAG_NCR53C400)
1863                 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);
1864         else
1865                 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1866 #endif                          /* def REAL_DMA */
1867
1868         dprintk(NDEBUG_DMA, ("scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG)));
1869
1870         /* 
1871          *      On the PAS16 at least I/O recovery delays are not needed here.
1872          *      Everyone else seems to want them.
1873          */
1874
1875         if (p & SR_IO) {
1876                 io_recovery_delay(1);
1877                 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1878         } else {
1879                 io_recovery_delay(1);
1880                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1881                 io_recovery_delay(1);
1882                 NCR5380_write(START_DMA_SEND_REG, 0);
1883                 io_recovery_delay(1);
1884         }
1885
1886 #if defined(REAL_DMA_POLL)
1887         do {
1888                 tmp = NCR5380_read(BUS_AND_STATUS_REG);
1889         } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER)));
1890
1891 /*
1892    At this point, either we've completed DMA, or we have a phase mismatch,
1893    or we've unexpectedly lost BUSY (which is a real error).
1894
1895    For write DMAs, we want to wait until the last byte has been
1896    transferred out over the bus before we turn off DMA mode.  Alas, there
1897    seems to be no terribly good way of doing this on a 5380 under all
1898    conditions.  For non-scatter-gather operations, we can wait until REQ
1899    and ACK both go false, or until a phase mismatch occurs.  Gather-writes
1900    are nastier, since the device will be expecting more data than we
1901    are prepared to send it, and REQ will remain asserted.  On a 53C8[01] we
1902    could test LAST BIT SENT to assure transfer (I imagine this is precisely
1903    why this signal was added to the newer chips) but on the older 538[01]
1904    this signal does not exist.  The workaround for this lack is a watchdog;
1905    we bail out of the wait-loop after a modest amount of wait-time if
1906    the usual exit conditions are not met.  Not a terribly clean or
1907    correct solution :-%
1908
1909    Reads are equally tricky due to a nasty characteristic of the NCR5380.
1910    If the chip is in DMA mode for an READ, it will respond to a target's
1911    REQ by latching the SCSI data into the INPUT DATA register and asserting
1912    ACK, even if it has _already_ been notified by the DMA controller that
1913    the current DMA transfer has completed!  If the NCR5380 is then taken
1914    out of DMA mode, this already-acknowledged byte is lost.
1915
1916    This is not a problem for "one DMA transfer per command" reads, because
1917    the situation will never arise... either all of the data is DMA'ed
1918    properly, or the target switches to MESSAGE IN phase to signal a
1919    disconnection (either operation bringing the DMA to a clean halt).
1920    However, in order to handle scatter-reads, we must work around the
1921    problem.  The chosen fix is to DMA N-2 bytes, then check for the
1922    condition before taking the NCR5380 out of DMA mode.  One or two extra
1923    bytes are transferred via PIO as necessary to fill out the original
1924    request.
1925  */
1926
1927         if (p & SR_IO) {
1928 #ifdef READ_OVERRUNS
1929                 udelay(10);
1930                 if (((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == (BASR_PHASE_MATCH | BASR_ACK))) {
1931                         saved_data = NCR5380_read(INPUT_DATA_REGISTER);
1932                         overrun = 1;
1933                 }
1934 #endif
1935         } else {
1936                 int limit = 100;
1937                 while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) {
1938                         if (!(tmp & BASR_PHASE_MATCH))
1939                                 break;
1940                         if (--limit < 0)
1941                                 break;
1942                 }
1943         }
1944
1945         dprintk(NDEBUG_DMA, ("scsi%d : polled DMA transfer complete, basr 0x%X, sr 0x%X\n", instance->host_no, tmp, NCR5380_read(STATUS_REG)));
1946
1947         NCR5380_write(MODE_REG, MR_BASE);
1948         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1949
1950         residue = NCR5380_dma_residual(instance);
1951         c -= residue;
1952         *count -= c;
1953         *data += c;
1954         *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
1955
1956 #ifdef READ_OVERRUNS
1957         if (*phase == p && (p & SR_IO) && residue == 0) {
1958                 if (overrun) {
1959                         dprintk(NDEBUG_DMA, ("Got an input overrun, using saved byte\n"));
1960                         **data = saved_data;
1961                         *data += 1;
1962                         *count -= 1;
1963                         cnt = toPIO = 1;
1964                 } else {
1965                         printk("No overrun??\n");
1966                         cnt = toPIO = 2;
1967                 }
1968                 dprintk(NDEBUG_DMA, ("Doing %d-byte PIO to 0x%X\n", cnt, *data));
1969                 NCR5380_transfer_pio(instance, phase, &cnt, data);
1970                 *count -= toPIO - cnt;
1971         }
1972 #endif
1973
1974         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)));
1975         return 0;
1976
1977 #elif defined(REAL_DMA)
1978         return 0;
1979 #else                           /* defined(REAL_DMA_POLL) */
1980         if (p & SR_IO) {
1981 #ifdef DMA_WORKS_RIGHT
1982                 foo = NCR5380_pread(instance, d, c);
1983 #else
1984                 int diff = 1;
1985                 if (hostdata->flags & FLAG_NCR53C400) {
1986                         diff = 0;
1987                 }
1988                 if (!(foo = NCR5380_pread(instance, d, c - diff))) {
1989                         /*
1990                          * We can't disable DMA mode after successfully transferring 
1991                          * what we plan to be the last byte, since that would open up
1992                          * a race condition where if the target asserted REQ before 
1993                          * we got the DMA mode reset, the NCR5380 would have latched
1994                          * an additional byte into the INPUT DATA register and we'd
1995                          * have dropped it.
1996                          * 
1997                          * The workaround was to transfer one fewer bytes than we 
1998                          * intended to with the pseudo-DMA read function, wait for 
1999                          * the chip to latch the last byte, read it, and then disable
2000                          * pseudo-DMA mode.
2001                          * 
2002                          * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
2003                          * REQ is deasserted when ACK is asserted, and not reasserted
2004                          * until ACK goes false.  Since the NCR5380 won't lower ACK
2005                          * until DACK is asserted, which won't happen unless we twiddle
2006                          * the DMA port or we take the NCR5380 out of DMA mode, we 
2007                          * can guarantee that we won't handshake another extra 
2008                          * byte.
2009                          */
2010
2011                         if (!(hostdata->flags & FLAG_NCR53C400)) {
2012                                 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ));
2013                                 /* Wait for clean handshake */
2014                                 while (NCR5380_read(STATUS_REG) & SR_REQ);
2015                                 d[c - 1] = NCR5380_read(INPUT_DATA_REG);
2016                         }
2017                 }
2018 #endif
2019         } else {
2020 #ifdef DMA_WORKS_RIGHT
2021                 foo = NCR5380_pwrite(instance, d, c);
2022 #else
2023                 int timeout;
2024                 dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c));
2025                 if (!(foo = NCR5380_pwrite(instance, d, c))) {
2026                         /*
2027                          * Wait for the last byte to be sent.  If REQ is being asserted for 
2028                          * the byte we're interested, we'll ACK it and it will go false.  
2029                          */
2030                         if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) {
2031                                 timeout = 20000;
2032                                 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH));
2033
2034                                 if (!timeout)
2035                                         dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no));
2036
2037                                 if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) {
2038                                         hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT;
2039                                         if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) {
2040                                                 hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT;
2041                                                 dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no));
2042                                         }
2043                                 }
2044                         } else {
2045                                 dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n"));
2046                                 while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT));
2047                                 dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n"));
2048                         }
2049                 }
2050 #endif
2051         }
2052         NCR5380_write(MODE_REG, MR_BASE);
2053         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2054
2055         if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) {
2056                 dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n"));
2057                 if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) {
2058                         dprintk(NDEBUG_C400_PWRITE, ("53C400w:    got it, reading reset interrupt reg\n"));
2059                         NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2060                 } else {
2061                         printk("53C400w:    IRQ NOT THERE!\n");
2062                 }
2063         }
2064         *data = d + c;
2065         *count = 0;
2066         *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
2067 #if defined(PSEUDO_DMA) && defined(UNSAFE)
2068         spin_lock_irq(instance->host_lock);
2069 #endif                          /* defined(REAL_DMA_POLL) */
2070         return foo;
2071 #endif                          /* def REAL_DMA */
2072 }
2073 #endif                          /* defined(REAL_DMA) | defined(PSEUDO_DMA) */
2074
2075 /*
2076  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
2077  *
2078  * Purpose : run through the various SCSI phases and do as the target 
2079  *      directs us to.  Operates on the currently connected command, 
2080  *      instance->connected.
2081  *
2082  * Inputs : instance, instance for which we are doing commands
2083  *
2084  * Side effects : SCSI things happen, the disconnected queue will be 
2085  *      modified if a command disconnects, *instance->connected will
2086  *      change.
2087  *
2088  * XXX Note : we need to watch for bus free or a reset condition here 
2089  *      to recover from an unexpected bus free condition.
2090  *
2091  * Locks: io_request_lock held by caller in IRQ mode
2092  */
2093
2094 static void NCR5380_information_transfer(struct Scsi_Host *instance) {
2095         NCR5380_local_declare();
2096         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata;
2097         unsigned char msgout = NOP;
2098         int sink = 0;
2099         int len;
2100 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2101         int transfersize;
2102 #endif
2103         unsigned char *data;
2104         unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2105         Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2106         /* RvC: we need to set the end of the polling time */
2107         unsigned long poll_time = jiffies + USLEEP_POLL;
2108
2109         NCR5380_setup(instance);
2110
2111         while (1) {
2112                 tmp = NCR5380_read(STATUS_REG);
2113                 /* We only have a valid SCSI phase when REQ is asserted */
2114                 if (tmp & SR_REQ) {
2115                         phase = (tmp & PHASE_MASK);
2116                         if (phase != old_phase) {
2117                                 old_phase = phase;
2118                                 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
2119                         }
2120                         if (sink && (phase != PHASE_MSGOUT)) {
2121                                 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2122
2123                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
2124                                 while (NCR5380_read(STATUS_REG) & SR_REQ);
2125                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2126                                 sink = 0;
2127                                 continue;
2128                         }
2129                         switch (phase) {
2130                         case PHASE_DATAIN:
2131                         case PHASE_DATAOUT:
2132 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2133                                 printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no);
2134                                 sink = 1;
2135                                 do_abort(instance);
2136                                 cmd->result = DID_ERROR << 16;
2137                                 cmd->done(cmd);
2138                                 return;
2139 #endif
2140                                 /* 
2141                                  * If there is no room left in the current buffer in the
2142                                  * scatter-gather list, move onto the next one.
2143                                  */
2144
2145                                 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2146                                         ++cmd->SCp.buffer;
2147                                         --cmd->SCp.buffers_residual;
2148                                         cmd->SCp.this_residual = cmd->SCp.buffer->length;
2149                                         cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+
2150                                                        cmd->SCp.buffer->offset;
2151                                         dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual));
2152                                 }
2153                                 /*
2154                                  * The preferred transfer method is going to be 
2155                                  * PSEUDO-DMA for systems that are strictly PIO,
2156                                  * since we can let the hardware do the handshaking.
2157                                  *
2158                                  * For this to work, we need to know the transfersize
2159                                  * ahead of time, since the pseudo-DMA code will sit
2160                                  * in an unconditional loop.
2161                                  */
2162
2163 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2164                                 /* KLL
2165                                  * PSEUDO_DMA is defined here. If this is the g_NCR5380
2166                                  * driver then it will always be defined, so the
2167                                  * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base
2168                                  * NCR5380 case.  I think this is a fairly clean solution.
2169                                  * We supplement these 2 if's with the flag.
2170                                  */
2171 #ifdef NCR5380_dma_xfer_len
2172                                 if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) {
2173 #else
2174                                 transfersize = cmd->transfersize;
2175
2176 #ifdef LIMIT_TRANSFERSIZE       /* If we have problems with interrupt service */
2177                                 if (transfersize > 512)
2178                                         transfersize = 512;
2179 #endif                          /* LIMIT_TRANSFERSIZE */
2180
2181                                 if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) {
2182                                         /* Limit transfers to 32K, for xx400 & xx406
2183                                          * pseudoDMA that transfers in 128 bytes blocks. */
2184                                         if (transfersize > 32 * 1024)
2185                                                 transfersize = 32 * 1024;
2186 #endif
2187                                         len = transfersize;
2188                                         if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) {
2189                                                 /*
2190                                                  * If the watchdog timer fires, all future accesses to this
2191                                                  * device will use the polled-IO.
2192                                                  */
2193                                                 printk("scsi%d : switching target %d lun %d to slow handshake\n", instance->host_no, cmd->device->id, cmd->device->lun);
2194                                                 cmd->device->borken = 1;
2195                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2196                                                 sink = 1;
2197                                                 do_abort(instance);
2198                                                 cmd->result = DID_ERROR << 16;
2199                                                 cmd->done(cmd);
2200                                                 /* XXX - need to source or sink data here, as appropriate */
2201                                         } else
2202                                                 cmd->SCp.this_residual -= transfersize - len;
2203                                 } else
2204 #endif                          /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */
2205                                         NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **)
2206                                                              &cmd->SCp.ptr);
2207                                 break;
2208                         case PHASE_MSGIN:
2209                                 len = 1;
2210                                 data = &tmp;
2211                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2212                                 cmd->SCp.Message = tmp;
2213
2214                                 switch (tmp) {
2215                                         /*
2216                                          * Linking lets us reduce the time required to get the 
2217                                          * next command out to the device, hopefully this will
2218                                          * mean we don't waste another revolution due to the delays
2219                                          * required by ARBITRATION and another SELECTION.
2220                                          *
2221                                          * In the current implementation proposal, low level drivers
2222                                          * merely have to start the next command, pointed to by 
2223                                          * next_link, done() is called as with unlinked commands.
2224                                          */
2225 #ifdef LINKED
2226                                 case LINKED_CMD_COMPLETE:
2227                                 case LINKED_FLG_CMD_COMPLETE:
2228                                         /* Accept message by clearing ACK */
2229                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2230                                         dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun));
2231                                         /* 
2232                                          * Sanity check : A linked command should only terminate with
2233                                          * one of these messages if there are more linked commands
2234                                          * available.
2235                                          */
2236                                         if (!cmd->next_link) {
2237                                                 printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun);
2238                                                 sink = 1;
2239                                                 do_abort(instance);
2240                                                 return;
2241                                         }
2242                                         initialize_SCp(cmd->next_link);
2243                                         /* The next command is still part of this process */
2244                                         cmd->next_link->tag = cmd->tag;
2245                                         cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2246                                         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));
2247                                         collect_stats(hostdata, cmd);
2248                                         cmd->scsi_done(cmd);
2249                                         cmd = hostdata->connected;
2250                                         break;
2251 #endif                          /* def LINKED */
2252                                 case ABORT:
2253                                 case COMMAND_COMPLETE:
2254                                         /* Accept message by clearing ACK */
2255                                         sink = 1;
2256                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2257                                         hostdata->connected = NULL;
2258                                         dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun));
2259                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2260
2261                                         /* 
2262                                          * I'm not sure what the correct thing to do here is : 
2263                                          * 
2264                                          * If the command that just executed is NOT a request 
2265                                          * sense, the obvious thing to do is to set the result
2266                                          * code to the values of the stored parameters.
2267                                          * 
2268                                          * If it was a REQUEST SENSE command, we need some way 
2269                                          * to differentiate between the failure code of the original
2270                                          * and the failure code of the REQUEST sense - the obvious
2271                                          * case is success, where we fall through and leave the result
2272                                          * code unchanged.
2273                                          * 
2274                                          * The non-obvious place is where the REQUEST SENSE failed 
2275                                          */
2276
2277                                         if (cmd->cmnd[0] != REQUEST_SENSE)
2278                                                 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2279                                         else if (status_byte(cmd->SCp.Status) != GOOD)
2280                                                 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2281
2282 #ifdef AUTOSENSE
2283                                         if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2284                                                 dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no));
2285                                                 cmd->cmnd[0] = REQUEST_SENSE;
2286                                                 cmd->cmnd[1] &= 0xe0;
2287                                                 cmd->cmnd[2] = 0;
2288                                                 cmd->cmnd[3] = 0;
2289                                                 cmd->cmnd[4] = sizeof(cmd->sense_buffer);
2290                                                 cmd->cmnd[5] = 0;
2291
2292                                                 cmd->SCp.buffer = NULL;
2293                                                 cmd->SCp.buffers_residual = 0;
2294                                                 cmd->SCp.ptr = (char *) cmd->sense_buffer;
2295                                                 cmd->SCp.this_residual = sizeof(cmd->sense_buffer);
2296
2297                                                 LIST(cmd, hostdata->issue_queue);
2298                                                 cmd->host_scribble = (unsigned char *)
2299                                                     hostdata->issue_queue;
2300                                                 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2301                                                 dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no));
2302                                         } else
2303 #endif                          /* def AUTOSENSE */
2304                                         {
2305                                                 collect_stats(hostdata, cmd);
2306                                                 cmd->scsi_done(cmd);
2307                                         }
2308
2309                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2310                                         /* 
2311                                          * Restore phase bits to 0 so an interrupted selection, 
2312                                          * arbitration can resume.
2313                                          */
2314                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2315
2316                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2317                                                 barrier();
2318                                         return;
2319                                 case MESSAGE_REJECT:
2320                                         /* Accept message by clearing ACK */
2321                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2322                                         switch (hostdata->last_message) {
2323                                         case HEAD_OF_QUEUE_TAG:
2324                                         case ORDERED_QUEUE_TAG:
2325                                         case SIMPLE_QUEUE_TAG:
2326                                                 cmd->device->simple_tags = 0;
2327                                                 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2328                                                 break;
2329                                         default:
2330                                                 break;
2331                                         }
2332                                 case DISCONNECT:{
2333                                                 /* Accept message by clearing ACK */
2334                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2335                                                 cmd->device->disconnect = 1;
2336                                                 LIST(cmd, hostdata->disconnected_queue);
2337                                                 cmd->host_scribble = (unsigned char *)
2338                                                     hostdata->disconnected_queue;
2339                                                 hostdata->connected = NULL;
2340                                                 hostdata->disconnected_queue = cmd;
2341                                                 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));
2342                                                 /* 
2343                                                  * Restore phase bits to 0 so an interrupted selection, 
2344                                                  * arbitration can resume.
2345                                                  */
2346                                                 NCR5380_write(TARGET_COMMAND_REG, 0);
2347
2348                                                 /* Enable reselect interrupts */
2349                                                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2350                                                 /* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/
2351                                                 /* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */
2352                                                 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2353                                                         barrier();
2354                                                 return;
2355                                         }
2356                                         /* 
2357                                          * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2358                                          * operation, in violation of the SCSI spec so we can safely 
2359                                          * ignore SAVE/RESTORE pointers calls.
2360                                          *
2361                                          * Unfortunately, some disks violate the SCSI spec and 
2362                                          * don't issue the required SAVE_POINTERS message before
2363                                          * disconnecting, and we have to break spec to remain 
2364                                          * compatible.
2365                                          */
2366                                 case SAVE_POINTERS:
2367                                 case RESTORE_POINTERS:
2368                                         /* Accept message by clearing ACK */
2369                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2370                                         break;
2371                                 case EXTENDED_MESSAGE:
2372 /* 
2373  * Extended messages are sent in the following format :
2374  * Byte         
2375  * 0            EXTENDED_MESSAGE == 1
2376  * 1            length (includes one byte for code, doesn't 
2377  *              include first two bytes)
2378  * 2            code
2379  * 3..length+1  arguments
2380  *
2381  * Start the extended message buffer with the EXTENDED_MESSAGE
2382  * byte, since scsi_print_msg() wants the whole thing.  
2383  */
2384                                         extended_msg[0] = EXTENDED_MESSAGE;
2385                                         /* Accept first byte by clearing ACK */
2386                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2387                                         dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no));
2388
2389                                         len = 2;
2390                                         data = extended_msg + 1;
2391                                         phase = PHASE_MSGIN;
2392                                         NCR5380_transfer_pio(instance, &phase, &len, &data);
2393
2394                                         dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2]));
2395
2396                                         if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) {
2397                                                 /* Accept third byte by clearing ACK */
2398                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2399                                                 len = extended_msg[1] - 1;
2400                                                 data = extended_msg + 3;
2401                                                 phase = PHASE_MSGIN;
2402
2403                                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2404                                                 dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len));
2405
2406                                                 switch (extended_msg[2]) {
2407                                                 case EXTENDED_SDTR:
2408                                                 case EXTENDED_WDTR:
2409                                                 case EXTENDED_MODIFY_DATA_POINTER:
2410                                                 case EXTENDED_EXTENDED_IDENTIFY:
2411                                                         tmp = 0;
2412                                                 }
2413                                         } else if (len) {
2414                                                 printk("scsi%d: error receiving extended message\n", instance->host_no);
2415                                                 tmp = 0;
2416                                         } else {
2417                                                 printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]);
2418                                                 tmp = 0;
2419                                         }
2420                                         /* Fall through to reject message */
2421
2422                                         /* 
2423                                          * If we get something weird that we aren't expecting, 
2424                                          * reject it.
2425                                          */
2426                                 default:
2427                                         if (!tmp) {
2428                                                 printk("scsi%d: rejecting message ", instance->host_no);
2429                                                 scsi_print_msg(extended_msg);
2430                                                 printk("\n");
2431                                         } else if (tmp != EXTENDED_MESSAGE)
2432                                                 printk("scsi%d: rejecting unknown message %02x from target %d, lun %d\n", instance->host_no, tmp, cmd->device->id, cmd->device->lun);
2433                                         else
2434                                                 printk("scsi%d: rejecting unknown extended message code %02x, length %d from target %d, lun %d\n", instance->host_no, extended_msg[1], extended_msg[0], cmd->device->id, cmd->device->lun);
2435
2436                                         msgout = MESSAGE_REJECT;
2437                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2438                                         break;
2439                                 }       /* switch (tmp) */
2440                                 break;
2441                         case PHASE_MSGOUT:
2442                                 len = 1;
2443                                 data = &msgout;
2444                                 hostdata->last_message = msgout;
2445                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2446                                 if (msgout == ABORT) {
2447                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2448                                         hostdata->connected = NULL;
2449                                         cmd->result = DID_ERROR << 16;
2450                                         collect_stats(hostdata, cmd);
2451                                         cmd->scsi_done(cmd);
2452                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2453                                         return;
2454                                 }
2455                                 msgout = NOP;
2456                                 break;
2457                         case PHASE_CMDOUT:
2458                                 len = cmd->cmd_len;
2459                                 data = cmd->cmnd;
2460                                 /* 
2461                                  * XXX for performance reasons, on machines with a 
2462                                  * PSEUDO-DMA architecture we should probably 
2463                                  * use the dma transfer function.  
2464                                  */
2465                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2466                                 if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) {
2467                                         NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2468                                         dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2469                                         return;
2470                                 }
2471                                 break;
2472                         case PHASE_STATIN:
2473                                 len = 1;
2474                                 data = &tmp;
2475                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2476                                 cmd->SCp.Status = tmp;
2477                                 break;
2478                         default:
2479                                 printk("scsi%d : unknown phase\n", instance->host_no);
2480                                 NCR5380_dprint(NDEBUG_ALL, instance);
2481                         }       /* switch(phase) */
2482                 }               /* if (tmp * SR_REQ) */
2483                 else {
2484                         /* RvC: go to sleep if polling time expired
2485                          */
2486                         if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) {
2487                                 NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2488                                 dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2489                                 return;
2490                         }
2491                 }
2492         }                       /* while (1) */
2493 }
2494
2495 /*
2496  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2497  *
2498  * Purpose : does reselection, initializing the instance->connected 
2499  *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q 
2500  *      nexus has been reestablished,
2501  *      
2502  * Inputs : instance - this instance of the NCR5380.
2503  *
2504  * Locks: io_request_lock held by caller if IRQ driven
2505  */
2506
2507 static void NCR5380_reselect(struct Scsi_Host *instance) {
2508         NCR5380_local_declare();
2509         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)
2510          instance->hostdata;
2511         unsigned char target_mask;
2512         unsigned char lun, phase;
2513         int len;
2514         unsigned char msg[3];
2515         unsigned char *data;
2516         Scsi_Cmnd *tmp = NULL, *prev;
2517         int abort = 0;
2518         NCR5380_setup(instance);
2519
2520         /*
2521          * Disable arbitration, etc. since the host adapter obviously
2522          * lost, and tell an interrupted NCR5380_select() to restart.
2523          */
2524
2525         NCR5380_write(MODE_REG, MR_BASE);
2526         hostdata->restart_select = 1;
2527
2528         target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2529         dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no));
2530
2531         /* 
2532          * At this point, we have detected that our SCSI ID is on the bus,
2533          * SEL is true and BSY was false for at least one bus settle delay
2534          * (400 ns).
2535          *
2536          * We must assert BSY ourselves, until the target drops the SEL
2537          * signal.
2538          */
2539
2540         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2541
2542         /* FIXME: timeout too long, must fail to workqueue */   
2543         if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0)
2544                 abort = 1;
2545                 
2546         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2547
2548         /*
2549          * Wait for target to go into MSGIN.
2550          * FIXME: timeout needed and fail to work queeu
2551          */
2552
2553         if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ))
2554                 abort = 1;
2555
2556         len = 1;
2557         data = msg;
2558         phase = PHASE_MSGIN;
2559         NCR5380_transfer_pio(instance, &phase, &len, &data);
2560
2561         if (!(msg[0] & 0x80)) {
2562                 printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no);
2563                 scsi_print_msg(msg);
2564                 abort = 1;
2565         } else {
2566                 /* Accept message by clearing ACK */
2567                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2568                 lun = (msg[0] & 0x07);
2569
2570                 /* 
2571                  * We need to add code for SCSI-II to track which devices have
2572                  * I_T_L_Q nexuses established, and which have simple I_T_L
2573                  * nexuses so we can chose to do additional data transfer.
2574                  */
2575
2576                 /* 
2577                  * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we 
2578                  * just reestablished, and remove it from the disconnected queue.
2579                  */
2580
2581
2582                 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
2583                         if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2584                             ) {
2585                                 if (prev) {
2586                                         REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
2587                                         prev->host_scribble = tmp->host_scribble;
2588                                 } else {
2589                                         REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble);
2590                                         hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble;
2591                                 }
2592                                 tmp->host_scribble = NULL;
2593                                 break;
2594                         }
2595                 if (!tmp) {
2596                         printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun);
2597                         /* 
2598                          * Since we have an established nexus that we can't do anything with,
2599                          * we must abort it.  
2600                          */
2601                         abort = 1;
2602                 }
2603         }
2604
2605         if (abort) {
2606                 do_abort(instance);
2607         } else {
2608                 hostdata->connected = tmp;
2609                 dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag));
2610         }
2611 }
2612
2613 /*
2614  * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
2615  *
2616  * Purpose : called by interrupt handler when DMA finishes or a phase
2617  *      mismatch occurs (which would finish the DMA transfer).  
2618  *
2619  * Inputs : instance - this instance of the NCR5380.
2620  *
2621  * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L
2622  *      nexus has been reestablished, on failure NULL is returned.
2623  */
2624
2625 #ifdef REAL_DMA
2626 static void NCR5380_dma_complete(NCR5380_instance * instance) {
2627         NCR5380_local_declare();
2628         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata * instance->hostdata);
2629         int transferred;
2630         NCR5380_setup(instance);
2631
2632         /*
2633          * XXX this might not be right.
2634          *
2635          * Wait for final byte to transfer, ie wait for ACK to go false.
2636          *
2637          * We should use the Last Byte Sent bit, unfortunately this is 
2638          * not available on the 5380/5381 (only the various CMOS chips)
2639          *
2640          * FIXME: timeout, and need to handle long timeout/irq case
2641          */
2642
2643         NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ);
2644
2645         NCR5380_write(MODE_REG, MR_BASE);
2646         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2647
2648         /*
2649          * The only places we should see a phase mismatch and have to send
2650          * data from the same set of pointers will be the data transfer
2651          * phases.  So, residual, requested length are only important here.
2652          */
2653
2654         if (!(hostdata->connected->SCp.phase & SR_CD)) {
2655                 transferred = instance->dmalen - NCR5380_dma_residual();
2656                 hostdata->connected->SCp.this_residual -= transferred;
2657                 hostdata->connected->SCp.ptr += transferred;
2658         }
2659 }
2660 #endif                          /* def REAL_DMA */
2661
2662 /*
2663  * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2664  *
2665  * Purpose : abort a command
2666  *
2667  * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the 
2668  *      host byte of the result field to, if zero DID_ABORTED is 
2669  *      used.
2670  *
2671  * Returns : 0 - success, -1 on failure.
2672  *
2673  *      XXX - there is no way to abort the command that is currently 
2674  *      connected, you have to wait for it to complete.  If this is 
2675  *      a problem, we could implement longjmp() / setjmp(), setjmp()
2676  *      called where the loop started in NCR5380_main().
2677  *
2678  * Locks: host lock taken by caller
2679  */
2680
2681 static int NCR5380_abort(Scsi_Cmnd * cmd) {
2682         NCR5380_local_declare();
2683         struct Scsi_Host *instance = cmd->device->host;
2684         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2685         Scsi_Cmnd *tmp, **prev;
2686         
2687         printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no);
2688         scsi_print_command(cmd);
2689
2690         NCR5380_print_status(instance);
2691
2692         NCR5380_setup(instance);
2693
2694         dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no));
2695         dprintk(NDEBUG_ABORT, ("        basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)));
2696
2697 #if 0
2698 /*
2699  * Case 1 : If the command is the currently executing command, 
2700  * we'll set the aborted flag and return control so that 
2701  * information transfer routine can exit cleanly.
2702  */
2703
2704         if (hostdata->connected == cmd) {
2705                 dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no));
2706                 hostdata->aborted = 1;
2707 /*
2708  * We should perform BSY checking, and make sure we haven't slipped
2709  * into BUS FREE.
2710  */
2711
2712                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN);
2713 /* 
2714  * Since we can't change phases until we've completed the current 
2715  * handshake, we have to source or sink a byte of data if the current
2716  * phase is not MSGOUT.
2717  */
2718
2719 /* 
2720  * Return control to the executing NCR drive so we can clear the
2721  * aborted flag and get back into our main loop.
2722  */
2723
2724                 return 0;
2725         }
2726 #endif
2727
2728 /* 
2729  * Case 2 : If the command hasn't been issued yet, we simply remove it 
2730  *          from the issue queue.
2731  */
2732  
2733         dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no));
2734         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)
2735                 if (cmd == tmp) {
2736                         REMOVE(5, *prev, tmp, tmp->host_scribble);
2737                         (*prev) = (Scsi_Cmnd *) tmp->host_scribble;
2738                         tmp->host_scribble = NULL;
2739                         tmp->result = DID_ABORT << 16;
2740                         dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no));
2741                         tmp->done(tmp);
2742                         return SUCCESS;
2743                 }
2744 #if (NDEBUG  & NDEBUG_ABORT)
2745         /* KLL */
2746                 else if (prev == tmp)
2747                         printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no);
2748 #endif
2749
2750 /* 
2751  * Case 3 : If any commands are connected, we're going to fail the abort
2752  *          and let the high level SCSI driver retry at a later time or 
2753  *          issue a reset.
2754  *
2755  *          Timeouts, and therefore aborted commands, will be highly unlikely
2756  *          and handling them cleanly in this situation would make the common
2757  *          case of noresets less efficient, and would pollute our code.  So,
2758  *          we fail.
2759  */
2760
2761         if (hostdata->connected) {
2762                 dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no));
2763                 return FAILED;
2764         }
2765 /*
2766  * Case 4: If the command is currently disconnected from the bus, and 
2767  *      there are no connected commands, we reconnect the I_T_L or 
2768  *      I_T_L_Q nexus associated with it, go into message out, and send 
2769  *      an abort message.
2770  *
2771  * This case is especially ugly. In order to reestablish the nexus, we
2772  * need to call NCR5380_select().  The easiest way to implement this 
2773  * function was to abort if the bus was busy, and let the interrupt
2774  * handler triggered on the SEL for reselect take care of lost arbitrations
2775  * where necessary, meaning interrupts need to be enabled.
2776  *
2777  * When interrupts are enabled, the queues may change - so we 
2778  * can't remove it from the disconnected queue before selecting it
2779  * because that could cause a failure in hashing the nexus if that 
2780  * device reselected.
2781  * 
2782  * Since the queues may change, we can't use the pointers from when we
2783  * first locate it.
2784  *
2785  * So, we must first locate the command, and if NCR5380_select()
2786  * succeeds, then issue the abort, relocate the command and remove
2787  * it from the disconnected queue.
2788  */
2789
2790         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble)
2791                 if (cmd == tmp) {
2792                         dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no));
2793
2794                         if (NCR5380_select(instance, cmd, (int) cmd->tag))
2795                                 return FAILED;
2796                         dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no));
2797
2798                         do_abort(instance);
2799
2800                         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)
2801                                 if (cmd == tmp) {
2802                                         REMOVE(5, *prev, tmp, tmp->host_scribble);
2803                                         *prev = (Scsi_Cmnd *) tmp->host_scribble;
2804                                         tmp->host_scribble = NULL;
2805                                         tmp->result = DID_ABORT << 16;
2806                                         tmp->done(tmp);
2807                                         return SUCCESS;
2808                                 }
2809                 }
2810 /*
2811  * Case 5 : If we reached this point, the command was not found in any of 
2812  *          the queues.
2813  *
2814  * We probably reached this point because of an unlikely race condition
2815  * between the command completing successfully and the abortion code,
2816  * so we won't panic, but we will notify the user in case something really
2817  * broke.
2818  */
2819         printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n"
2820                         "         before abortion\n", instance->host_no);
2821         return FAILED;
2822 }
2823
2824
2825 /* 
2826  * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd)
2827  * 
2828  * Purpose : reset the SCSI bus.
2829  *
2830  * Returns : SUCCESS
2831  *
2832  * Locks: host lock taken by caller
2833  */
2834
2835 static int NCR5380_bus_reset(Scsi_Cmnd * cmd)
2836 {
2837         struct Scsi_Host *instance = cmd->device->host;
2838
2839         NCR5380_local_declare();
2840         NCR5380_setup(instance);
2841         NCR5380_print_status(instance);
2842
2843         spin_lock_irq(instance->host_lock);
2844         do_reset(instance);
2845         spin_unlock_irq(instance->host_lock);
2846
2847         return SUCCESS;
2848 }