config: tegra3: enable /dev mount with ACL
[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@lxorguk.ukuu.org.uk)
34  * Fixed up the timer lockups reported so far. Things still suck. Looking 
35  * forward to 2.3 and per device request queues. Then it'll be possible to
36  * SMP thread this beast and improve life no end.
37  
38  * Revision 1.9  1997/7/27      Ronald van Cuijlenborg
39  *                              (ronald.van.cuijlenborg@tip.nl or nutty@dds.nl)
40  * (hopefully) fixed and enhanced USLEEP
41  * added support for DTC3181E card (for Mustek scanner)
42  *
43
44  * Revision 1.8                 Ingmar Baumgart
45  *                              (ingmar@gonzo.schwaben.de)
46  * added support for NCR53C400a card
47  *
48
49  * Revision 1.7  1996/3/2       Ray Van Tassle (rayvt@comm.mot.com)
50  * added proc_info
51  * added support needed for DTC 3180/3280
52  * fixed a couple of bugs
53  *
54
55  * Revision 1.5  1994/01/19  09:14:57  drew
56  * Fixed udelay() hack that was being used on DATAOUT phases
57  * instead of a proper wait for the final handshake.
58  *
59  * Revision 1.4  1994/01/19  06:44:25  drew
60  * *** empty log message ***
61  *
62  * Revision 1.3  1994/01/19  05:24:40  drew
63  * Added support for TCR LAST_BYTE_SENT bit.
64  *
65  * Revision 1.2  1994/01/15  06:14:11  drew
66  * REAL DMA support, bug fixes.
67  *
68  * Revision 1.1  1994/01/15  06:00:54  drew
69  * Initial revision
70  *
71  */
72
73 /*
74  * Further development / testing that should be done : 
75  * 1.  Cleanup the NCR5380_transfer_dma function and DMA operation complete
76  *     code so that everything does the same thing that's done at the 
77  *     end of a pseudo-DMA read operation.
78  *
79  * 2.  Fix REAL_DMA (interrupt driven, polled works fine) -
80  *     basically, transfer size needs to be reduced by one 
81  *     and the last byte read as is done with PSEUDO_DMA.
82  * 
83  * 4.  Test SCSI-II tagged queueing (I have no devices which support 
84  *      tagged queueing)
85  *
86  * 5.  Test linked command handling code after Eric is ready with 
87  *      the high level code.
88  */
89 #include <scsi/scsi_dbg.h>
90 #include <scsi/scsi_transport_spi.h>
91
92 #ifndef NDEBUG
93 #define NDEBUG 0
94 #endif
95 #ifndef NDEBUG_ABORT
96 #define NDEBUG_ABORT 0
97 #endif
98
99 #if (NDEBUG & NDEBUG_LISTS)
100 #define LIST(x,y) {printk("LINE:%d   Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); if ((x)==(y)) udelay(5); }
101 #define REMOVE(w,x,y,z) {printk("LINE:%d   Removing: %p->%p  %p->%p \n", __LINE__, (void*)(w), (void*)(x), (void*)(y), (void*)(z)); if ((x)==(y)) udelay(5); }
102 #else
103 #define LIST(x,y)
104 #define REMOVE(w,x,y,z)
105 #endif
106
107 #ifndef notyet
108 #undef LINKED
109 #undef REAL_DMA
110 #endif
111
112 #ifdef REAL_DMA_POLL
113 #undef READ_OVERRUNS
114 #define READ_OVERRUNS
115 #endif
116
117 #ifdef BOARD_REQUIRES_NO_DELAY
118 #define io_recovery_delay(x)
119 #else
120 #define io_recovery_delay(x)    udelay(x)
121 #endif
122
123 /*
124  * Design
125  *
126  * This is a generic 5380 driver.  To use it on a different platform, 
127  * one simply writes appropriate system specific macros (ie, data
128  * transfer - some PC's will use the I/O bus, 68K's must use 
129  * memory mapped) and drops this file in their 'C' wrapper.
130  *
131  * (Note from hch:  unfortunately it was not enough for the different
132  * m68k folks and instead of improving this driver they copied it
133  * and hacked it up for their needs.  As a consequence they lost
134  * most updates to this driver.  Maybe someone will fix all these
135  * drivers to use a common core one day..)
136  *
137  * As far as command queueing, two queues are maintained for 
138  * each 5380 in the system - commands that haven't been issued yet,
139  * and commands that are currently executing.  This means that an 
140  * unlimited number of commands may be queued, letting 
141  * more commands propagate from the higher driver levels giving higher 
142  * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported, 
143  * allowing multiple commands to propagate all the way to a SCSI-II device 
144  * while a command is already executing.
145  *
146  *
147  * Issues specific to the NCR5380 : 
148  *
149  * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 
150  * piece of hardware that requires you to sit in a loop polling for 
151  * the REQ signal as long as you are connected.  Some devices are 
152  * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 
153  * while doing long seek operations.
154  * 
155  * The workaround for this is to keep track of devices that have
156  * disconnected.  If the device hasn't disconnected, for commands that
157  * should disconnect, we do something like 
158  *
159  * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
160  * 
161  * Some tweaking of N and M needs to be done.  An algorithm based 
162  * on "time to data" would give the best results as long as short time
163  * to datas (ie, on the same track) were considered, however these 
164  * broken devices are the exception rather than the rule and I'd rather
165  * spend my time optimizing for the normal case.
166  *
167  * Architecture :
168  *
169  * At the heart of the design is a coroutine, NCR5380_main,
170  * which is started from a workqueue for each NCR5380 host in the
171  * system.  It attempts to establish I_T_L or I_T_L_Q nexuses by
172  * removing the commands from the issue queue and calling
173  * NCR5380_select() if a nexus is not established. 
174  *
175  * Once a nexus is established, the NCR5380_information_transfer()
176  * phase goes through the various phases as instructed by the target.
177  * if the target goes into MSG IN and sends a DISCONNECT message,
178  * the command structure is placed into the per instance disconnected
179  * queue, and NCR5380_main tries to find more work.  If the target is 
180  * idle for too long, the system will try to sleep.
181  *
182  * If a command has disconnected, eventually an interrupt will trigger,
183  * calling NCR5380_intr()  which will in turn call NCR5380_reselect
184  * to reestablish a nexus.  This will run main if necessary.
185  *
186  * On command termination, the done function will be called as 
187  * appropriate.
188  *
189  * SCSI pointers are maintained in the SCp field of SCSI command 
190  * structures, being initialized after the command is connected
191  * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
192  * Note that in violation of the standard, an implicit SAVE POINTERS operation
193  * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
194  */
195
196 /*
197  * Using this file :
198  * This file a skeleton Linux SCSI driver for the NCR 5380 series
199  * of chips.  To use it, you write an architecture specific functions 
200  * and macros and include this file in your driver.
201  *
202  * These macros control options : 
203  * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be 
204  *      defined.
205  * 
206  * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
207  *      for commands that return with a CHECK CONDITION status. 
208  *
209  * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
210  *      transceivers. 
211  *
212  * DONT_USE_INTR - if defined, never use interrupts, even if we probe or
213  *      override-configure an IRQ.
214  *
215  * LIMIT_TRANSFERSIZE - if defined, limit the pseudo-dma transfers to 512
216  *      bytes at a time.  Since interrupts are disabled by default during
217  *      these transfers, we might need this to give reasonable interrupt
218  *      service time if the transfer size gets too large.
219  *
220  * LINKED - if defined, linked commands are supported.
221  *
222  * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
223  *
224  * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
225  *
226  * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't
227  *      rely on phase mismatch and EOP interrupts to determine end 
228  *      of phase.
229  *
230  * UNSAFE - leave interrupts enabled during pseudo-DMA transfers.  You
231  *          only really want to use this if you're having a problem with
232  *          dropped characters during high speed communications, and even
233  *          then, you're going to be better off twiddling with transfersize
234  *          in the high level code.
235  *
236  * Defaults for these will be provided although the user may want to adjust 
237  * these to allocate CPU resources to the SCSI driver or "real" code.
238  * 
239  * USLEEP_SLEEP - amount of time, in jiffies, to sleep
240  *
241  * USLEEP_POLL - amount of time, in jiffies, to poll
242  *
243  * These macros MUST be defined :
244  * NCR5380_local_declare() - declare any local variables needed for your
245  *      transfer routines.
246  *
247  * NCR5380_setup(instance) - initialize any local variables needed from a given
248  *      instance of the host adapter for NCR5380_{read,write,pread,pwrite}
249  * 
250  * NCR5380_read(register)  - read from the specified register
251  *
252  * NCR5380_write(register, value) - write to the specific register 
253  *
254  * NCR5380_implementation_fields  - additional fields needed for this 
255  *      specific implementation of the NCR5380
256  *
257  * Either real DMA *or* pseudo DMA may be implemented
258  * REAL functions : 
259  * NCR5380_REAL_DMA should be defined if real DMA is to be used.
260  * Note that the DMA setup functions should return the number of bytes 
261  *      that they were able to program the controller for.
262  *
263  * Also note that generic i386/PC versions of these macros are 
264  *      available as NCR5380_i386_dma_write_setup,
265  *      NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
266  *
267  * NCR5380_dma_write_setup(instance, src, count) - initialize
268  * NCR5380_dma_read_setup(instance, dst, count) - initialize
269  * NCR5380_dma_residual(instance); - residual count
270  *
271  * PSEUDO functions :
272  * NCR5380_pwrite(instance, src, count)
273  * NCR5380_pread(instance, dst, count);
274  *
275  * The generic driver is initialized by calling NCR5380_init(instance),
276  * after setting the appropriate host specific fields and ID.  If the 
277  * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
278  * possible) function may be used.
279  */
280
281 static int do_abort(struct Scsi_Host *host);
282 static void do_reset(struct Scsi_Host *host);
283
284 /*
285  *      initialize_SCp          -       init the scsi pointer field
286  *      @cmd: command block to set up
287  *
288  *      Set up the internal fields in the SCSI command.
289  */
290
291 static __inline__ void initialize_SCp(Scsi_Cmnd * cmd)
292 {
293         /* 
294          * Initialize the Scsi Pointer field so that all of the commands in the 
295          * various queues are valid.
296          */
297
298         if (scsi_bufflen(cmd)) {
299                 cmd->SCp.buffer = scsi_sglist(cmd);
300                 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
301                 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
302                 cmd->SCp.this_residual = cmd->SCp.buffer->length;
303         } else {
304                 cmd->SCp.buffer = NULL;
305                 cmd->SCp.buffers_residual = 0;
306                 cmd->SCp.ptr = NULL;
307                 cmd->SCp.this_residual = 0;
308         }
309 }
310
311 /**
312  *      NCR5380_poll_politely   -       wait for NCR5380 status bits
313  *      @instance: controller to poll
314  *      @reg: 5380 register to poll
315  *      @bit: Bitmask to check
316  *      @val: Value required to exit
317  *
318  *      Polls the NCR5380 in a reasonably efficient manner waiting for
319  *      an event to occur, after a short quick poll we begin giving the
320  *      CPU back in non IRQ contexts
321  *
322  *      Returns the value of the register or a negative error code.
323  */
324  
325 static int NCR5380_poll_politely(struct Scsi_Host *instance, int reg, int bit, int val, int t)
326 {
327         NCR5380_local_declare();
328         int n = 500;            /* At about 8uS a cycle for the cpu access */
329         unsigned long end = jiffies + t;
330         int r;
331         
332         NCR5380_setup(instance);
333
334         while( n-- > 0)
335         {
336                 r = NCR5380_read(reg);
337                 if((r & bit) == val)
338                         return 0;
339                 cpu_relax();
340         }
341         
342         /* t time yet ? */
343         while(time_before(jiffies, end))
344         {
345                 r = NCR5380_read(reg);
346                 if((r & bit) == val)
347                         return 0;
348                 if(!in_interrupt())
349                         cond_resched();
350                 else
351                         cpu_relax();
352         }
353         return -ETIMEDOUT;
354 }
355
356 static struct {
357         unsigned char value;
358         const char *name;
359 } phases[] __maybe_unused = {
360         {PHASE_DATAOUT, "DATAOUT"}, 
361         {PHASE_DATAIN, "DATAIN"}, 
362         {PHASE_CMDOUT, "CMDOUT"}, 
363         {PHASE_STATIN, "STATIN"}, 
364         {PHASE_MSGOUT, "MSGOUT"}, 
365         {PHASE_MSGIN, "MSGIN"}, 
366         {PHASE_UNKNOWN, "UNKNOWN"}
367 };
368
369 #if NDEBUG
370 static struct {
371         unsigned char mask;
372         const char *name;
373 } signals[] = { 
374         {SR_DBP, "PARITY"}, 
375         {SR_RST, "RST"}, 
376         {SR_BSY, "BSY"}, 
377         {SR_REQ, "REQ"}, 
378         {SR_MSG, "MSG"}, 
379         {SR_CD, "CD"}, 
380         {SR_IO, "IO"}, 
381         {SR_SEL, "SEL"}, 
382         {0, NULL}
383 }, 
384 basrs[] = {
385         {BASR_ATN, "ATN"}, 
386         {BASR_ACK, "ACK"}, 
387         {0, NULL}
388 }, 
389 icrs[] = { 
390         {ICR_ASSERT_RST, "ASSERT RST"}, 
391         {ICR_ASSERT_ACK, "ASSERT ACK"}, 
392         {ICR_ASSERT_BSY, "ASSERT BSY"}, 
393         {ICR_ASSERT_SEL, "ASSERT SEL"}, 
394         {ICR_ASSERT_ATN, "ASSERT ATN"}, 
395         {ICR_ASSERT_DATA, "ASSERT DATA"}, 
396         {0, NULL}
397 }, 
398 mrs[] = { 
399         {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, 
400         {MR_TARGET, "MODE TARGET"}, 
401         {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, 
402         {MR_ENABLE_PAR_INTR, "MODE PARITY INTR"}, 
403         {MR_MONITOR_BSY, "MODE MONITOR BSY"}, 
404         {MR_DMA_MODE, "MODE DMA"}, 
405         {MR_ARBITRATE, "MODE ARBITRATION"}, 
406         {0, NULL}
407 };
408
409 /**
410  *      NCR5380_print   -       print scsi bus signals
411  *      @instance:      adapter state to dump
412  *
413  *      Print the SCSI bus signals for debugging purposes
414  *
415  *      Locks: caller holds hostdata lock (not essential)
416  */
417
418 static void NCR5380_print(struct Scsi_Host *instance)
419 {
420         NCR5380_local_declare();
421         unsigned char status, data, basr, mr, icr, i;
422         NCR5380_setup(instance);
423
424         data = NCR5380_read(CURRENT_SCSI_DATA_REG);
425         status = NCR5380_read(STATUS_REG);
426         mr = NCR5380_read(MODE_REG);
427         icr = NCR5380_read(INITIATOR_COMMAND_REG);
428         basr = NCR5380_read(BUS_AND_STATUS_REG);
429
430         printk("STATUS_REG: %02x ", status);
431         for (i = 0; signals[i].mask; ++i)
432                 if (status & signals[i].mask)
433                         printk(",%s", signals[i].name);
434         printk("\nBASR: %02x ", basr);
435         for (i = 0; basrs[i].mask; ++i)
436                 if (basr & basrs[i].mask)
437                         printk(",%s", basrs[i].name);
438         printk("\nICR: %02x ", icr);
439         for (i = 0; icrs[i].mask; ++i)
440                 if (icr & icrs[i].mask)
441                         printk(",%s", icrs[i].name);
442         printk("\nMODE: %02x ", mr);
443         for (i = 0; mrs[i].mask; ++i)
444                 if (mr & mrs[i].mask)
445                         printk(",%s", mrs[i].name);
446         printk("\n");
447 }
448
449
450 /* 
451  *      NCR5380_print_phase     -       show SCSI phase
452  *      @instance: adapter to dump
453  *
454  *      Print the current SCSI phase for debugging purposes
455  *
456  *      Locks: none
457  */
458
459 static void NCR5380_print_phase(struct Scsi_Host *instance)
460 {
461         NCR5380_local_declare();
462         unsigned char status;
463         int i;
464         NCR5380_setup(instance);
465
466         status = NCR5380_read(STATUS_REG);
467         if (!(status & SR_REQ))
468                 printk("scsi%d : REQ not asserted, phase unknown.\n", instance->host_no);
469         else {
470                 for (i = 0; (phases[i].value != PHASE_UNKNOWN) && (phases[i].value != (status & PHASE_MASK)); ++i);
471                 printk("scsi%d : phase %s\n", instance->host_no, phases[i].name);
472         }
473 }
474 #endif
475
476 /*
477  * These need tweaking, and would probably work best as per-device 
478  * flags initialized differently for disk, tape, cd, etc devices.
479  * People with broken devices are free to experiment as to what gives
480  * the best results for them.
481  *
482  * USLEEP_SLEEP should be a minimum seek time.
483  *
484  * USLEEP_POLL should be a maximum rotational latency.
485  */
486 #ifndef USLEEP_SLEEP
487 /* 20 ms (reasonable hard disk speed) */
488 #define USLEEP_SLEEP (20*HZ/1000)
489 #endif
490 /* 300 RPM (floppy speed) */
491 #ifndef USLEEP_POLL
492 #define USLEEP_POLL (200*HZ/1000)
493 #endif
494 #ifndef USLEEP_WAITLONG
495 /* RvC: (reasonable time to wait on select error) */
496 #define USLEEP_WAITLONG USLEEP_SLEEP
497 #endif
498
499 /* 
500  * Function : int should_disconnect (unsigned char cmd)
501  *
502  * Purpose : decide whether a command would normally disconnect or 
503  *      not, since if it won't disconnect we should go to sleep.
504  *
505  * Input : cmd - opcode of SCSI command
506  *
507  * Returns : DISCONNECT_LONG if we should disconnect for a really long 
508  *      time (ie always, sleep, look for REQ active, sleep), 
509  *      DISCONNECT_TIME_TO_DATA if we would only disconnect for a normal
510  *      time-to-data delay, DISCONNECT_NONE if this command would return
511  *      immediately.
512  *
513  *      Future sleep algorithms based on time to data can exploit 
514  *      something like this so they can differentiate between "normal" 
515  *      (ie, read, write, seek) and unusual commands (ie, * format).
516  *
517  * Note : We don't deal with commands that handle an immediate disconnect,
518  *        
519  */
520
521 static int should_disconnect(unsigned char cmd)
522 {
523         switch (cmd) {
524         case READ_6:
525         case WRITE_6:
526         case SEEK_6:
527         case READ_10:
528         case WRITE_10:
529         case SEEK_10:
530                 return DISCONNECT_TIME_TO_DATA;
531         case FORMAT_UNIT:
532         case SEARCH_HIGH:
533         case SEARCH_LOW:
534         case SEARCH_EQUAL:
535                 return DISCONNECT_LONG;
536         default:
537                 return DISCONNECT_NONE;
538         }
539 }
540
541 static void NCR5380_set_timer(struct NCR5380_hostdata *hostdata, unsigned long timeout)
542 {
543         hostdata->time_expires = jiffies + timeout;
544         schedule_delayed_work(&hostdata->coroutine, timeout);
545 }
546
547
548 static int probe_irq __initdata = 0;
549
550 /**
551  *      probe_intr      -       helper for IRQ autoprobe
552  *      @irq: interrupt number
553  *      @dev_id: unused
554  *      @regs: unused
555  *
556  *      Set a flag to indicate the IRQ in question was received. This is
557  *      used by the IRQ probe code.
558  */
559  
560 static irqreturn_t __init probe_intr(int irq, void *dev_id)
561 {
562         probe_irq = irq;
563         return IRQ_HANDLED;
564 }
565
566 /**
567  *      NCR5380_probe_irq       -       find the IRQ of an NCR5380
568  *      @instance: NCR5380 controller
569  *      @possible: bitmask of ISA IRQ lines
570  *
571  *      Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ
572  *      and then looking to see what interrupt actually turned up.
573  *
574  *      Locks: none, irqs must be enabled on entry
575  */
576
577 static int __init __maybe_unused NCR5380_probe_irq(struct Scsi_Host *instance,
578                                                 int possible)
579 {
580         NCR5380_local_declare();
581         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
582         unsigned long timeout;
583         int trying_irqs, i, mask;
584         NCR5380_setup(instance);
585
586         for (trying_irqs = i = 0, mask = 1; i < 16; ++i, mask <<= 1)
587                 if ((mask & possible) && (request_irq(i, &probe_intr, IRQF_DISABLED, "NCR-probe", NULL) == 0))
588                         trying_irqs |= mask;
589
590         timeout = jiffies + (250 * HZ / 1000);
591         probe_irq = SCSI_IRQ_NONE;
592
593         /*
594          * A interrupt is triggered whenever BSY = false, SEL = true
595          * and a bit set in the SELECT_ENABLE_REG is asserted on the 
596          * SCSI bus.
597          *
598          * Note that the bus is only driven when the phase control signals
599          * (I/O, C/D, and MSG) match those in the TCR, so we must reset that
600          * to zero.
601          */
602
603         NCR5380_write(TARGET_COMMAND_REG, 0);
604         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
605         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
606         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL);
607
608         while (probe_irq == SCSI_IRQ_NONE && time_before(jiffies, timeout))
609                 schedule_timeout_uninterruptible(1);
610         
611         NCR5380_write(SELECT_ENABLE_REG, 0);
612         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
613
614         for (i = 0, mask = 1; i < 16; ++i, mask <<= 1)
615                 if (trying_irqs & mask)
616                         free_irq(i, NULL);
617
618         return probe_irq;
619 }
620
621 /**
622  *      NCR58380_print_options  -       show options
623  *      @instance: unused for now
624  *
625  *      Called by probe code indicating the NCR5380 driver options that 
626  *      were selected. At some point this will switch to runtime options
627  *      read from the adapter in question
628  *
629  *      Locks: none
630  */
631
632 static void __init __maybe_unused
633 NCR5380_print_options(struct Scsi_Host *instance)
634 {
635         printk(" generic options"
636 #ifdef AUTOPROBE_IRQ
637                " AUTOPROBE_IRQ"
638 #endif
639 #ifdef AUTOSENSE
640                " AUTOSENSE"
641 #endif
642 #ifdef DIFFERENTIAL
643                " DIFFERENTIAL"
644 #endif
645 #ifdef REAL_DMA
646                " REAL DMA"
647 #endif
648 #ifdef REAL_DMA_POLL
649                " REAL DMA POLL"
650 #endif
651 #ifdef PARITY
652                " PARITY"
653 #endif
654 #ifdef PSEUDO_DMA
655                " PSEUDO DMA"
656 #endif
657 #ifdef UNSAFE
658                " UNSAFE "
659 #endif
660             );
661         printk(" USLEEP, USLEEP_POLL=%d USLEEP_SLEEP=%d", USLEEP_POLL, USLEEP_SLEEP);
662         printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
663         if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) {
664                 printk(" ncr53c400 release=%d", NCR53C400_PUBLIC_RELEASE);
665         }
666 }
667
668 /**
669  *      NCR5380_print_status    -       dump controller info
670  *      @instance: controller to dump
671  *
672  *      Print commands in the various queues, called from NCR5380_abort 
673  *      and NCR5380_debug to aid debugging.
674  *
675  *      Locks: called functions disable irqs
676  */
677
678 static void NCR5380_print_status(struct Scsi_Host *instance)
679 {
680         NCR5380_dprint(NDEBUG_ANY, instance);
681         NCR5380_dprint_phase(NDEBUG_ANY, instance);
682 }
683
684 /******************************************/
685 /*
686  * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
687  *
688  * *buffer: I/O buffer
689  * **start: if inout == FALSE pointer into buffer where user read should start
690  * offset: current offset
691  * length: length of buffer
692  * hostno: Scsi_Host host_no
693  * inout: TRUE - user is writing; FALSE - user is reading
694  *
695  * Return the number of bytes read from or written
696  */
697
698 #undef SPRINTF
699 #define SPRINTF(args...) do { if(pos < buffer + length-80) pos += sprintf(pos, ## args); } while(0)
700 static
701 char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length);
702 static
703 char *lprint_command(unsigned char *cmd, char *pos, char *buffer, int len);
704 static
705 char *lprint_opcode(int opcode, char *pos, char *buffer, int length);
706
707 static int __maybe_unused NCR5380_proc_info(struct Scsi_Host *instance,
708         char *buffer, char **start, off_t offset, int length, int inout)
709 {
710         char *pos = buffer;
711         struct NCR5380_hostdata *hostdata;
712         Scsi_Cmnd *ptr;
713
714         hostdata = (struct NCR5380_hostdata *) instance->hostdata;
715
716         if (inout) {            /* Has data been written to the file ? */
717 #ifdef DTC_PUBLIC_RELEASE
718                 dtc_wmaxi = dtc_maxi = 0;
719 #endif
720 #ifdef PAS16_PUBLIC_RELEASE
721                 pas_wmaxi = pas_maxi = 0;
722 #endif
723                 return (-ENOSYS);       /* Currently this is a no-op */
724         }
725         SPRINTF("NCR5380 core release=%d.   ", NCR5380_PUBLIC_RELEASE);
726         if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400)
727                 SPRINTF("ncr53c400 release=%d.  ", NCR53C400_PUBLIC_RELEASE);
728 #ifdef DTC_PUBLIC_RELEASE
729         SPRINTF("DTC 3180/3280 release %d", DTC_PUBLIC_RELEASE);
730 #endif
731 #ifdef T128_PUBLIC_RELEASE
732         SPRINTF("T128 release %d", T128_PUBLIC_RELEASE);
733 #endif
734 #ifdef GENERIC_NCR5380_PUBLIC_RELEASE
735         SPRINTF("Generic5380 release %d", GENERIC_NCR5380_PUBLIC_RELEASE);
736 #endif
737 #ifdef PAS16_PUBLIC_RELEASE
738         SPRINTF("PAS16 release=%d", PAS16_PUBLIC_RELEASE);
739 #endif
740
741         SPRINTF("\nBase Addr: 0x%05lX    ", (long) instance->base);
742         SPRINTF("io_port: %04x      ", (int) instance->io_port);
743         if (instance->irq == SCSI_IRQ_NONE)
744                 SPRINTF("IRQ: None.\n");
745         else
746                 SPRINTF("IRQ: %d.\n", instance->irq);
747
748 #ifdef DTC_PUBLIC_RELEASE
749         SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", dtc_wmaxi, dtc_maxi);
750 #endif
751 #ifdef PAS16_PUBLIC_RELEASE
752         SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", pas_wmaxi, pas_maxi);
753 #endif
754         spin_lock_irq(instance->host_lock);
755         if (!hostdata->connected)
756                 SPRINTF("scsi%d: no currently connected command\n", instance->host_no);
757         else
758                 pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, pos, buffer, length);
759         SPRINTF("scsi%d: issue_queue\n", instance->host_no);
760         for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
761                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
762
763         SPRINTF("scsi%d: disconnected_queue\n", instance->host_no);
764         for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
765                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
766         spin_unlock_irq(instance->host_lock);
767         
768         *start = buffer;
769         if (pos - buffer < offset)
770                 return 0;
771         else if (pos - buffer - offset < length)
772                 return pos - buffer - offset;
773         return length;
774 }
775
776 static char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length)
777 {
778         SPRINTF("scsi%d : destination target %d, lun %d\n", cmd->device->host->host_no, cmd->device->id, cmd->device->lun);
779         SPRINTF("        command = ");
780         pos = lprint_command(cmd->cmnd, pos, buffer, length);
781         return (pos);
782 }
783
784 static char *lprint_command(unsigned char *command, char *pos, char *buffer, int length)
785 {
786         int i, s;
787         pos = lprint_opcode(command[0], pos, buffer, length);
788         for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
789                 SPRINTF("%02x ", command[i]);
790         SPRINTF("\n");
791         return (pos);
792 }
793
794 static char *lprint_opcode(int opcode, char *pos, char *buffer, int length)
795 {
796         SPRINTF("%2d (0x%02x)", opcode, opcode);
797         return (pos);
798 }
799
800
801 /**
802  *      NCR5380_init    -       initialise an NCR5380
803  *      @instance: adapter to configure
804  *      @flags: control flags
805  *
806  *      Initializes *instance and corresponding 5380 chip,
807  *      with flags OR'd into the initial flags value.
808  *
809  *      Notes : I assume that the host, hostno, and id bits have been
810  *      set correctly.  I don't care about the irq and other fields. 
811  *
812  *      Returns 0 for success
813  *
814  *      Locks: interrupts must be enabled when we are called 
815  */
816
817 static int __devinit NCR5380_init(struct Scsi_Host *instance, int flags)
818 {
819         NCR5380_local_declare();
820         int i, pass;
821         unsigned long timeout;
822         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
823
824         if(in_interrupt())
825                 printk(KERN_ERR "NCR5380_init called with interrupts off!\n");
826         /* 
827          * On NCR53C400 boards, NCR5380 registers are mapped 8 past 
828          * the base address.
829          */
830
831 #ifdef NCR53C400
832         if (flags & FLAG_NCR53C400)
833                 instance->NCR5380_instance_name += NCR53C400_address_adjust;
834 #endif
835
836         NCR5380_setup(instance);
837
838         hostdata->aborted = 0;
839         hostdata->id_mask = 1 << instance->this_id;
840         for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
841                 if (i > hostdata->id_mask)
842                         hostdata->id_higher_mask |= i;
843         for (i = 0; i < 8; ++i)
844                 hostdata->busy[i] = 0;
845 #ifdef REAL_DMA
846         hostdata->dmalen = 0;
847 #endif
848         hostdata->targets_present = 0;
849         hostdata->connected = NULL;
850         hostdata->issue_queue = NULL;
851         hostdata->disconnected_queue = NULL;
852         
853         INIT_DELAYED_WORK(&hostdata->coroutine, NCR5380_main);
854         
855 #ifdef NCR5380_STATS
856         for (i = 0; i < 8; ++i) {
857                 hostdata->time_read[i] = 0;
858                 hostdata->time_write[i] = 0;
859                 hostdata->bytes_read[i] = 0;
860                 hostdata->bytes_write[i] = 0;
861         }
862         hostdata->timebase = 0;
863         hostdata->pendingw = 0;
864         hostdata->pendingr = 0;
865 #endif
866
867         /* The CHECK code seems to break the 53C400. Will check it later maybe */
868         if (flags & FLAG_NCR53C400)
869                 hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags;
870         else
871                 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags;
872
873         hostdata->host = instance;
874         hostdata->time_expires = 0;
875
876 #ifndef AUTOSENSE
877         if ((instance->cmd_per_lun > 1) || instance->can_queue > 1)
878                     printk(KERN_WARNING "scsi%d : WARNING : support for multiple outstanding commands enabled\n" "         without AUTOSENSE option, contingent allegiance conditions may\n"
879                            "         be incorrectly cleared.\n", instance->host_no);
880 #endif                          /* def AUTOSENSE */
881
882         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
883         NCR5380_write(MODE_REG, MR_BASE);
884         NCR5380_write(TARGET_COMMAND_REG, 0);
885         NCR5380_write(SELECT_ENABLE_REG, 0);
886
887 #ifdef NCR53C400
888         if (hostdata->flags & FLAG_NCR53C400) {
889                 NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE);
890         }
891 #endif
892
893         /* 
894          * Detect and correct bus wedge problems.
895          *
896          * If the system crashed, it may have crashed in a state 
897          * where a SCSI command was still executing, and the 
898          * SCSI bus is not in a BUS FREE STATE.
899          *
900          * If this is the case, we'll try to abort the currently
901          * established nexus which we know nothing about, and that
902          * failing, do a hard reset of the SCSI bus 
903          */
904
905         for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
906                 switch (pass) {
907                 case 1:
908                 case 3:
909                 case 5:
910                         printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no);
911                         timeout = jiffies + 5 * HZ;
912                         NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ);
913                         break;
914                 case 2:
915                         printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no);
916                         do_abort(instance);
917                         break;
918                 case 4:
919                         printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no);
920                         do_reset(instance);
921                         break;
922                 case 6:
923                         printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no);
924                         return -ENXIO;
925                 }
926         }
927         return 0;
928 }
929
930 /**
931  *      NCR5380_exit    -       remove an NCR5380
932  *      @instance: adapter to remove
933  */
934
935 static void NCR5380_exit(struct Scsi_Host *instance)
936 {
937         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
938
939         cancel_delayed_work_sync(&hostdata->coroutine);
940 }
941
942 /**
943  *      NCR5380_queue_command           -       queue a command
944  *      @cmd: SCSI command
945  *      @done: completion handler
946  *
947  *      cmd is added to the per instance issue_queue, with minor 
948  *      twiddling done to the host specific fields of cmd.  If the 
949  *      main coroutine is not running, it is restarted.
950  *
951  *      Locks: host lock taken by caller
952  */
953
954 static int NCR5380_queue_command_lck(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *))
955 {
956         struct Scsi_Host *instance = cmd->device->host;
957         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
958         Scsi_Cmnd *tmp;
959
960 #if (NDEBUG & NDEBUG_NO_WRITE)
961         switch (cmd->cmnd[0]) {
962         case WRITE_6:
963         case WRITE_10:
964                 printk("scsi%d : WRITE attempted with NO_WRITE debugging flag set\n", instance->host_no);
965                 cmd->result = (DID_ERROR << 16);
966                 done(cmd);
967                 return 0;
968         }
969 #endif                          /* (NDEBUG & NDEBUG_NO_WRITE) */
970
971 #ifdef NCR5380_STATS
972         switch (cmd->cmnd[0]) {
973                 case WRITE:
974                 case WRITE_6:
975                 case WRITE_10:
976                         hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
977                         hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);
978                         hostdata->pendingw++;
979                         break;
980                 case READ:
981                 case READ_6:
982                 case READ_10:
983                         hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
984                         hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);
985                         hostdata->pendingr++;
986                         break;
987         }
988 #endif
989
990         /* 
991          * We use the host_scribble field as a pointer to the next command  
992          * in a queue 
993          */
994
995         cmd->host_scribble = NULL;
996         cmd->scsi_done = done;
997         cmd->result = 0;
998
999         /* 
1000          * Insert the cmd into the issue queue. Note that REQUEST SENSE 
1001          * commands are added to the head of the queue since any command will
1002          * clear the contingent allegiance condition that exists and the 
1003          * sense data is only guaranteed to be valid while the condition exists.
1004          */
1005
1006         if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
1007                 LIST(cmd, hostdata->issue_queue);
1008                 cmd->host_scribble = (unsigned char *) hostdata->issue_queue;
1009                 hostdata->issue_queue = cmd;
1010         } else {
1011                 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp->host_scribble; tmp = (Scsi_Cmnd *) tmp->host_scribble);
1012                 LIST(cmd, tmp);
1013                 tmp->host_scribble = (unsigned char *) cmd;
1014         }
1015         dprintk(NDEBUG_QUEUES, ("scsi%d : command added to %s of queue\n", instance->host_no, (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"));
1016
1017         /* Run the coroutine if it isn't already running. */
1018         /* Kick off command processing */
1019         schedule_delayed_work(&hostdata->coroutine, 0);
1020         return 0;
1021 }
1022
1023 static DEF_SCSI_QCMD(NCR5380_queue_command)
1024
1025 /**
1026  *      NCR5380_main    -       NCR state machines
1027  *
1028  *      NCR5380_main is a coroutine that runs as long as more work can 
1029  *      be done on the NCR5380 host adapters in a system.  Both 
1030  *      NCR5380_queue_command() and NCR5380_intr() will try to start it 
1031  *      in case it is not running.
1032  * 
1033  *      Locks: called as its own thread with no locks held. Takes the
1034  *      host lock and called routines may take the isa dma lock.
1035  */
1036
1037 static void NCR5380_main(struct work_struct *work)
1038 {
1039         struct NCR5380_hostdata *hostdata =
1040                 container_of(work, struct NCR5380_hostdata, coroutine.work);
1041         struct Scsi_Host *instance = hostdata->host;
1042         Scsi_Cmnd *tmp, *prev;
1043         int done;
1044         
1045         spin_lock_irq(instance->host_lock);
1046         do {
1047                 /* Lock held here */
1048                 done = 1;
1049                 if (!hostdata->connected && !hostdata->selecting) {
1050                         dprintk(NDEBUG_MAIN, ("scsi%d : not connected\n", instance->host_no));
1051                         /*
1052                          * Search through the issue_queue for a command destined
1053                          * for a target that's not busy.
1054                          */
1055                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble) 
1056                         {
1057                                 if (prev != tmp)
1058                                         dprintk(NDEBUG_LISTS, ("MAIN tmp=%p   target=%d   busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun));
1059                                 /*  When we find one, remove it from the issue queue. */
1060                                 if (!(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))) {
1061                                         if (prev) {
1062                                                 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
1063                                                 prev->host_scribble = tmp->host_scribble;
1064                                         } else {
1065                                                 REMOVE(-1, hostdata->issue_queue, tmp, tmp->host_scribble);
1066                                                 hostdata->issue_queue = (Scsi_Cmnd *) tmp->host_scribble;
1067                                         }
1068                                         tmp->host_scribble = NULL;
1069
1070                                         /* 
1071                                          * Attempt to establish an I_T_L nexus here. 
1072                                          * On success, instance->hostdata->connected is set.
1073                                          * On failure, we must add the command back to the
1074                                          *   issue queue so we can keep trying. 
1075                                          */
1076                                         dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main() : command for target %d lun %d removed from issue_queue\n", instance->host_no, tmp->target, tmp->lun));
1077         
1078                                         /*
1079                                          * A successful selection is defined as one that 
1080                                          * leaves us with the command connected and 
1081                                          * in hostdata->connected, OR has terminated the
1082                                          * command.
1083                                          *
1084                                          * With successful commands, we fall through
1085                                          * and see if we can do an information transfer,
1086                                          * with failures we will restart.
1087                                          */
1088                                         hostdata->selecting = NULL;
1089                                         /* RvC: have to preset this to indicate a new command is being performed */
1090
1091                                         if (!NCR5380_select(instance, tmp,
1092                                                             /* 
1093                                                              * REQUEST SENSE commands are issued without tagged
1094                                                              * queueing, even on SCSI-II devices because the 
1095                                                              * contingent allegiance condition exists for the 
1096                                                              * entire unit.
1097                                                              */
1098                                                             (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1099                                                 break;
1100                                         } else {
1101                                                 LIST(tmp, hostdata->issue_queue);
1102                                                 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1103                                                 hostdata->issue_queue = tmp;
1104                                                 done = 0;
1105                                                 dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main(): select() failed, returned to issue_queue\n", instance->host_no));
1106                                         }
1107                                         /* lock held here still */
1108                                 }       /* if target/lun is not busy */
1109                         }       /* for */
1110                         /* exited locked */
1111                 }       /* if (!hostdata->connected) */
1112                 if (hostdata->selecting) {
1113                         tmp = (Scsi_Cmnd *) hostdata->selecting;
1114                         /* Selection will drop and retake the lock */
1115                         if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1116                                 /* Ok ?? */
1117                         } else {
1118                                 /* RvC: device failed, so we wait a long time
1119                                    this is needed for Mustek scanners, that
1120                                    do not respond to commands immediately
1121                                    after a scan */
1122                                 printk(KERN_DEBUG "scsi%d: device %d did not respond in time\n", instance->host_no, tmp->device->id);
1123                                 LIST(tmp, hostdata->issue_queue);
1124                                 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1125                                 hostdata->issue_queue = tmp;
1126                                 NCR5380_set_timer(hostdata, USLEEP_WAITLONG);
1127                         }
1128                 }       /* if hostdata->selecting */
1129                 if (hostdata->connected
1130 #ifdef REAL_DMA
1131                     && !hostdata->dmalen
1132 #endif
1133                     && (!hostdata->time_expires || time_before_eq(hostdata->time_expires, jiffies))
1134                     ) {
1135                         dprintk(NDEBUG_MAIN, ("scsi%d : main() : performing information transfer\n", instance->host_no));
1136                         NCR5380_information_transfer(instance);
1137                         dprintk(NDEBUG_MAIN, ("scsi%d : main() : done set false\n", instance->host_no));
1138                         done = 0;
1139                 } else
1140                         break;
1141         } while (!done);
1142         
1143         spin_unlock_irq(instance->host_lock);
1144 }
1145
1146 #ifndef DONT_USE_INTR
1147
1148 /**
1149  *      NCR5380_intr    -       generic NCR5380 irq handler
1150  *      @irq: interrupt number
1151  *      @dev_id: device info
1152  *
1153  *      Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1154  *      from the disconnected queue, and restarting NCR5380_main() 
1155  *      as required.
1156  *
1157  *      Locks: takes the needed instance locks
1158  */
1159
1160 static irqreturn_t NCR5380_intr(int dummy, void *dev_id)
1161 {
1162         NCR5380_local_declare();
1163         struct Scsi_Host *instance = dev_id;
1164         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1165         int done;
1166         unsigned char basr;
1167         unsigned long flags;
1168
1169         dprintk(NDEBUG_INTR, ("scsi : NCR5380 irq %d triggered\n",
1170                 instance->irq));
1171
1172         do {
1173                 done = 1;
1174                 spin_lock_irqsave(instance->host_lock, flags);
1175                 /* Look for pending interrupts */
1176                 NCR5380_setup(instance);
1177                 basr = NCR5380_read(BUS_AND_STATUS_REG);
1178                 /* XXX dispatch to appropriate routine if found and done=0 */
1179                 if (basr & BASR_IRQ) {
1180                         NCR5380_dprint(NDEBUG_INTR, instance);
1181                         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1182                                 done = 0;
1183                                 dprintk(NDEBUG_INTR, ("scsi%d : SEL interrupt\n", instance->host_no));
1184                                 NCR5380_reselect(instance);
1185                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1186                         } else if (basr & BASR_PARITY_ERROR) {
1187                                 dprintk(NDEBUG_INTR, ("scsi%d : PARITY interrupt\n", instance->host_no));
1188                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1189                         } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1190                                 dprintk(NDEBUG_INTR, ("scsi%d : RESET interrupt\n", instance->host_no));
1191                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1192                         } else {
1193 #if defined(REAL_DMA)
1194                                 /*
1195                                  * We should only get PHASE MISMATCH and EOP interrupts
1196                                  * if we have DMA enabled, so do a sanity check based on
1197                                  * the current setting of the MODE register.
1198                                  */
1199
1200                                 if ((NCR5380_read(MODE_REG) & MR_DMA) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) {
1201                                         int transferred;
1202
1203                                         if (!hostdata->connected)
1204                                                 panic("scsi%d : received end of DMA interrupt with no connected cmd\n", instance->hostno);
1205
1206                                         transferred = (hostdata->dmalen - NCR5380_dma_residual(instance));
1207                                         hostdata->connected->SCp.this_residual -= transferred;
1208                                         hostdata->connected->SCp.ptr += transferred;
1209                                         hostdata->dmalen = 0;
1210
1211                                         (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1212                                                         
1213                                         /* FIXME: we need to poll briefly then defer a workqueue task ! */
1214                                         NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2*HZ);
1215
1216                                         NCR5380_write(MODE_REG, MR_BASE);
1217                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1218                                 }
1219 #else
1220                                 dprintk(NDEBUG_INTR, ("scsi : unknown interrupt, BASR 0x%X, MR 0x%X, SR 0x%x\n", basr, NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)));
1221                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1222 #endif
1223                         }
1224                 }       /* if BASR_IRQ */
1225                 spin_unlock_irqrestore(instance->host_lock, flags);
1226                 if(!done)
1227                         schedule_delayed_work(&hostdata->coroutine, 0);
1228         } while (!done);
1229         return IRQ_HANDLED;
1230 }
1231
1232 #endif 
1233
1234 /**
1235  *      collect_stats           -       collect stats on a scsi command
1236  *      @hostdata: adapter 
1237  *      @cmd: command being issued
1238  *
1239  *      Update the statistical data by parsing the command in question
1240  */
1241  
1242 static void collect_stats(struct NCR5380_hostdata *hostdata, Scsi_Cmnd * cmd) 
1243 {
1244 #ifdef NCR5380_STATS
1245         switch (cmd->cmnd[0]) {
1246         case WRITE:
1247         case WRITE_6:
1248         case WRITE_10:
1249                 hostdata->time_write[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1250                 hostdata->pendingw--;
1251                 break;
1252         case READ:
1253         case READ_6:
1254         case READ_10:
1255                 hostdata->time_read[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1256                 hostdata->pendingr--;
1257                 break;
1258         }
1259 #endif
1260 }
1261
1262
1263 /* 
1264  * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, 
1265  *      int tag);
1266  *
1267  * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1268  *      including ARBITRATION, SELECTION, and initial message out for 
1269  *      IDENTIFY and queue messages. 
1270  *
1271  * Inputs : instance - instantiation of the 5380 driver on which this 
1272  *      target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for 
1273  *      new tag, TAG_NONE for untagged queueing, otherwise set to the tag for 
1274  *      the command that is presently connected.
1275  * 
1276  * Returns : -1 if selection could not execute for some reason,
1277  *      0 if selection succeeded or failed because the target 
1278  *      did not respond.
1279  *
1280  * Side effects : 
1281  *      If bus busy, arbitration failed, etc, NCR5380_select() will exit 
1282  *              with registers as they should have been on entry - ie
1283  *              SELECT_ENABLE will be set appropriately, the NCR5380
1284  *              will cease to drive any SCSI bus signals.
1285  *
1286  *      If successful : I_T_L or I_T_L_Q nexus will be established, 
1287  *              instance->connected will be set to cmd.  
1288  *              SELECT interrupt will be disabled.
1289  *
1290  *      If failed (no target) : cmd->scsi_done() will be called, and the 
1291  *              cmd->result host byte set to DID_BAD_TARGET.
1292  *
1293  *      Locks: caller holds hostdata lock in IRQ mode
1294  */
1295  
1296 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag) 
1297 {
1298         NCR5380_local_declare();
1299         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1300         unsigned char tmp[3], phase;
1301         unsigned char *data;
1302         int len;
1303         unsigned long timeout;
1304         unsigned char value;
1305         int err;
1306         NCR5380_setup(instance);
1307
1308         if (hostdata->selecting)
1309                 goto part2;
1310
1311         hostdata->restart_select = 0;
1312
1313         NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1314         dprintk(NDEBUG_ARBITRATION, ("scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id));
1315
1316         /* 
1317          * Set the phase bits to 0, otherwise the NCR5380 won't drive the 
1318          * data bus during SELECTION.
1319          */
1320
1321         NCR5380_write(TARGET_COMMAND_REG, 0);
1322
1323         /* 
1324          * Start arbitration.
1325          */
1326
1327         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1328         NCR5380_write(MODE_REG, MR_ARBITRATE);
1329
1330
1331         /* We can be relaxed here, interrupts are on, we are
1332            in workqueue context, the birds are singing in the trees */
1333         spin_unlock_irq(instance->host_lock);
1334         err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ);
1335         spin_lock_irq(instance->host_lock);
1336         if (err < 0) {
1337                 printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__);
1338                 NCR5380_write(MODE_REG, MR_BASE);
1339                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1340                 goto failed;
1341         }
1342
1343         dprintk(NDEBUG_ARBITRATION, ("scsi%d : arbitration complete\n", instance->host_no));
1344
1345         /* 
1346          * The arbitration delay is 2.2us, but this is a minimum and there is 
1347          * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1348          * the integral nature of udelay().
1349          *
1350          */
1351
1352         udelay(3);
1353
1354         /* Check for lost arbitration */
1355         if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1356                 NCR5380_write(MODE_REG, MR_BASE);
1357                 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no));
1358                 goto failed;
1359         }
1360         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL);
1361
1362         if (!(hostdata->flags & FLAG_DTC3181E) &&
1363             /* RvC: DTC3181E has some trouble with this
1364              *      so we simply removed it. Seems to work with
1365              *      only Mustek scanner attached
1366              */
1367             (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1368                 NCR5380_write(MODE_REG, MR_BASE);
1369                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1370                 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no));
1371                 goto failed;
1372         }
1373         /* 
1374          * Again, bus clear + bus settle time is 1.2us, however, this is 
1375          * a minimum so we'll udelay ceil(1.2)
1376          */
1377
1378         udelay(2);
1379
1380         dprintk(NDEBUG_ARBITRATION, ("scsi%d : won arbitration\n", instance->host_no));
1381
1382         /* 
1383          * Now that we have won arbitration, start Selection process, asserting 
1384          * the host and target ID's on the SCSI bus.
1385          */
1386
1387         NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << scmd_id(cmd))));
1388
1389         /* 
1390          * Raise ATN while SEL is true before BSY goes false from arbitration,
1391          * since this is the only way to guarantee that we'll get a MESSAGE OUT
1392          * phase immediately after selection.
1393          */
1394
1395         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1396         NCR5380_write(MODE_REG, MR_BASE);
1397
1398         /* 
1399          * Reselect interrupts must be turned off prior to the dropping of BSY,
1400          * otherwise we will trigger an interrupt.
1401          */
1402         NCR5380_write(SELECT_ENABLE_REG, 0);
1403
1404         /*
1405          * The initiator shall then wait at least two deskew delays and release 
1406          * the BSY signal.
1407          */
1408         udelay(1);              /* wingel -- wait two bus deskew delay >2*45ns */
1409
1410         /* Reset BSY */
1411         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1412
1413         /* 
1414          * Something weird happens when we cease to drive BSY - looks
1415          * like the board/chip is letting us do another read before the 
1416          * appropriate propagation delay has expired, and we're confusing
1417          * a BSY signal from ourselves as the target's response to SELECTION.
1418          *
1419          * A small delay (the 'C++' frontend breaks the pipeline with an
1420          * unnecessary jump, making it work on my 386-33/Trantor T128, the
1421          * tighter 'C' code breaks and requires this) solves the problem - 
1422          * the 1 us delay is arbitrary, and only used because this delay will 
1423          * be the same on other platforms and since it works here, it should 
1424          * work there.
1425          *
1426          * wingel suggests that this could be due to failing to wait
1427          * one deskew delay.
1428          */
1429
1430         udelay(1);
1431
1432         dprintk(NDEBUG_SELECTION, ("scsi%d : selecting target %d\n", instance->host_no, scmd_id(cmd)));
1433
1434         /* 
1435          * The SCSI specification calls for a 250 ms timeout for the actual 
1436          * selection.
1437          */
1438
1439         timeout = jiffies + (250 * HZ / 1000);
1440
1441         /* 
1442          * XXX very interesting - we're seeing a bounce where the BSY we 
1443          * asserted is being reflected / still asserted (propagation delay?)
1444          * and it's detecting as true.  Sigh.
1445          */
1446
1447         hostdata->select_time = 0;      /* we count the clock ticks at which we polled */
1448         hostdata->selecting = cmd;
1449
1450 part2:
1451         /* RvC: here we enter after a sleeping period, or immediately after
1452            execution of part 1
1453            we poll only once ech clock tick */
1454         value = NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO);
1455
1456         if (!value && (hostdata->select_time < HZ/4)) {
1457                 /* RvC: we still must wait for a device response */
1458                 hostdata->select_time++;        /* after 25 ticks the device has failed */
1459                 NCR5380_set_timer(hostdata, 1);
1460                 return 0;       /* RvC: we return here with hostdata->selecting set,
1461                                    to go to sleep */
1462         }
1463
1464         hostdata->selecting = NULL;/* clear this pointer, because we passed the
1465                                            waiting period */
1466         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1467                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1468                 NCR5380_reselect(instance);
1469                 printk("scsi%d : reselection after won arbitration?\n", instance->host_no);
1470                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1471                 return -1;
1472         }
1473         /* 
1474          * No less than two deskew delays after the initiator detects the 
1475          * BSY signal is true, it shall release the SEL signal and may 
1476          * change the DATA BUS.                                     -wingel
1477          */
1478
1479         udelay(1);
1480
1481         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1482
1483         if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1484                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1485                 if (hostdata->targets_present & (1 << scmd_id(cmd))) {
1486                         printk(KERN_DEBUG "scsi%d : weirdness\n", instance->host_no);
1487                         if (hostdata->restart_select)
1488                                 printk(KERN_DEBUG "\trestart select\n");
1489                         NCR5380_dprint(NDEBUG_SELECTION, instance);
1490                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1491                         return -1;
1492                 }
1493                 cmd->result = DID_BAD_TARGET << 16;
1494                 collect_stats(hostdata, cmd);
1495                 cmd->scsi_done(cmd);
1496                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1497                 dprintk(NDEBUG_SELECTION, ("scsi%d : target did not respond within 250ms\n", instance->host_no));
1498                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1499                 return 0;
1500         }
1501         hostdata->targets_present |= (1 << scmd_id(cmd));
1502
1503         /*
1504          * Since we followed the SCSI spec, and raised ATN while SEL 
1505          * was true but before BSY was false during selection, the information
1506          * transfer phase should be a MESSAGE OUT phase so that we can send the
1507          * IDENTIFY message.
1508          * 
1509          * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1510          * message (2 bytes) with a tag ID that we increment with every command
1511          * until it wraps back to 0.
1512          *
1513          * XXX - it turns out that there are some broken SCSI-II devices,
1514          *       which claim to support tagged queuing but fail when more than
1515          *       some number of commands are issued at once.
1516          */
1517
1518         /* Wait for start of REQ/ACK handshake */
1519
1520         spin_unlock_irq(instance->host_lock);
1521         err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
1522         spin_lock_irq(instance->host_lock);
1523         
1524         if(err) {
1525                 printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__);
1526                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1527                 goto failed;
1528         }
1529
1530         dprintk(NDEBUG_SELECTION, ("scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id));
1531         tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun);
1532
1533         len = 1;
1534         cmd->tag = 0;
1535
1536         /* Send message(s) */
1537         data = tmp;
1538         phase = PHASE_MSGOUT;
1539         NCR5380_transfer_pio(instance, &phase, &len, &data);
1540         dprintk(NDEBUG_SELECTION, ("scsi%d : nexus established.\n", instance->host_no));
1541         /* XXX need to handle errors here */
1542         hostdata->connected = cmd;
1543         hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1544
1545         initialize_SCp(cmd);
1546
1547         return 0;
1548
1549         /* Selection failed */
1550 failed:
1551         return -1;
1552
1553 }
1554
1555 /* 
1556  * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, 
1557  *      unsigned char *phase, int *count, unsigned char **data)
1558  *
1559  * Purpose : transfers data in given phase using polled I/O
1560  *
1561  * Inputs : instance - instance of driver, *phase - pointer to 
1562  *      what phase is expected, *count - pointer to number of 
1563  *      bytes to transfer, **data - pointer to data pointer.
1564  * 
1565  * Returns : -1 when different phase is entered without transferring
1566  *      maximum number of bytes, 0 if all bytes or transferred or exit
1567  *      is in same phase.
1568  *
1569  *      Also, *phase, *count, *data are modified in place.
1570  *
1571  * XXX Note : handling for bus free may be useful.
1572  */
1573
1574 /*
1575  * Note : this code is not as quick as it could be, however it 
1576  * IS 100% reliable, and for the actual data transfer where speed
1577  * counts, we will always do a pseudo DMA or DMA transfer.
1578  */
1579
1580 static int NCR5380_transfer_pio(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1581         NCR5380_local_declare();
1582         unsigned char p = *phase, tmp;
1583         int c = *count;
1584         unsigned char *d = *data;
1585         /*
1586          *      RvC: some administrative data to process polling time
1587          */
1588         int break_allowed = 0;
1589         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1590         NCR5380_setup(instance);
1591
1592         if (!(p & SR_IO))
1593                 dprintk(NDEBUG_PIO, ("scsi%d : pio write %d bytes\n", instance->host_no, c));
1594         else
1595                 dprintk(NDEBUG_PIO, ("scsi%d : pio read %d bytes\n", instance->host_no, c));
1596
1597         /* 
1598          * The NCR5380 chip will only drive the SCSI bus when the 
1599          * phase specified in the appropriate bits of the TARGET COMMAND
1600          * REGISTER match the STATUS REGISTER
1601          */
1602
1603          NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1604
1605         /* RvC: don't know if this is necessary, but other SCSI I/O is short
1606          *      so breaks are not necessary there
1607          */
1608         if ((p == PHASE_DATAIN) || (p == PHASE_DATAOUT)) {
1609                 break_allowed = 1;
1610         }
1611         do {
1612                 /* 
1613                  * Wait for assertion of REQ, after which the phase bits will be 
1614                  * valid 
1615                  */
1616
1617                 /* RvC: we simply poll once, after that we stop temporarily
1618                  *      and let the device buffer fill up
1619                  *      if breaking is not allowed, we keep polling as long as needed
1620                  */
1621
1622                 /* FIXME */
1623                 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ) && !break_allowed);
1624                 if (!(tmp & SR_REQ)) {
1625                         /* timeout condition */
1626                         NCR5380_set_timer(hostdata, USLEEP_SLEEP);
1627                         break;
1628                 }
1629
1630                 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : REQ detected\n", instance->host_no));
1631
1632                 /* Check for phase mismatch */
1633                 if ((tmp & PHASE_MASK) != p) {
1634                         dprintk(NDEBUG_HANDSHAKE, ("scsi%d : phase mismatch\n", instance->host_no));
1635                         NCR5380_dprint_phase(NDEBUG_HANDSHAKE, instance);
1636                         break;
1637                 }
1638                 /* Do actual transfer from SCSI bus to / from memory */
1639                 if (!(p & SR_IO))
1640                         NCR5380_write(OUTPUT_DATA_REG, *d);
1641                 else
1642                         *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1643
1644                 ++d;
1645
1646                 /* 
1647                  * The SCSI standard suggests that in MSGOUT phase, the initiator
1648                  * should drop ATN on the last byte of the message phase
1649                  * after REQ has been asserted for the handshake but before
1650                  * the initiator raises ACK.
1651                  */
1652
1653                 if (!(p & SR_IO)) {
1654                         if (!((p & SR_MSG) && c > 1)) {
1655                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1656                                 NCR5380_dprint(NDEBUG_PIO, instance);
1657                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1658                         } else {
1659                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1660                                 NCR5380_dprint(NDEBUG_PIO, instance);
1661                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1662                         }
1663                 } else {
1664                         NCR5380_dprint(NDEBUG_PIO, instance);
1665                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1666                 }
1667
1668                 /* FIXME - if this fails bus reset ?? */
1669                 NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, 0, 5*HZ);
1670                 dprintk(NDEBUG_HANDSHAKE, ("scsi%d : req false, handshake complete\n", instance->host_no));
1671
1672 /*
1673  * We have several special cases to consider during REQ/ACK handshaking : 
1674  * 1.  We were in MSGOUT phase, and we are on the last byte of the 
1675  *      message.  ATN must be dropped as ACK is dropped.
1676  *
1677  * 2.  We are in a MSGIN phase, and we are on the last byte of the  
1678  *      message.  We must exit with ACK asserted, so that the calling
1679  *      code may raise ATN before dropping ACK to reject the message.
1680  *
1681  * 3.  ACK and ATN are clear and the target may proceed as normal.
1682  */
1683                 if (!(p == PHASE_MSGIN && c == 1)) {
1684                         if (p == PHASE_MSGOUT && c > 1)
1685                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1686                         else
1687                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1688                 }
1689         } while (--c);
1690
1691         dprintk(NDEBUG_PIO, ("scsi%d : residual %d\n", instance->host_no, c));
1692
1693         *count = c;
1694         *data = d;
1695         tmp = NCR5380_read(STATUS_REG);
1696         if (tmp & SR_REQ)
1697                 *phase = tmp & PHASE_MASK;
1698         else
1699                 *phase = PHASE_UNKNOWN;
1700
1701         if (!c || (*phase == p))
1702                 return 0;
1703         else
1704                 return -1;
1705 }
1706
1707 /**
1708  *      do_reset        -       issue a reset command
1709  *      @host: adapter to reset
1710  *
1711  *      Issue a reset sequence to the NCR5380 and try and get the bus
1712  *      back into sane shape.
1713  *
1714  *      Locks: caller holds queue lock
1715  */
1716  
1717 static void do_reset(struct Scsi_Host *host) {
1718         NCR5380_local_declare();
1719         NCR5380_setup(host);
1720
1721         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
1722         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
1723         udelay(25);
1724         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1725 }
1726
1727 /*
1728  * Function : do_abort (Scsi_Host *host)
1729  * 
1730  * Purpose : abort the currently established nexus.  Should only be 
1731  *      called from a routine which can drop into a 
1732  * 
1733  * Returns : 0 on success, -1 on failure.
1734  *
1735  * Locks: queue lock held by caller
1736  *      FIXME: sort this out and get new_eh running
1737  */
1738
1739 static int do_abort(struct Scsi_Host *host) {
1740         NCR5380_local_declare();
1741         unsigned char *msgptr, phase, tmp;
1742         int len;
1743         int rc;
1744         NCR5380_setup(host);
1745
1746
1747         /* Request message out phase */
1748         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1749
1750         /* 
1751          * Wait for the target to indicate a valid phase by asserting 
1752          * REQ.  Once this happens, we'll have either a MSGOUT phase 
1753          * and can immediately send the ABORT message, or we'll have some 
1754          * other phase and will have to source/sink data.
1755          * 
1756          * We really don't care what value was on the bus or what value
1757          * the target sees, so we just handshake.
1758          */
1759
1760         rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, SR_REQ, 60 * HZ);
1761         
1762         if(rc < 0)
1763                 return -1;
1764
1765         tmp = (unsigned char)rc;
1766         
1767         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1768
1769         if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1770                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1771                 rc = NCR5380_poll_politely(host, STATUS_REG, SR_REQ, 0, 3*HZ);
1772                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1773                 if(rc == -1)
1774                         return -1;
1775         }
1776         tmp = ABORT;
1777         msgptr = &tmp;
1778         len = 1;
1779         phase = PHASE_MSGOUT;
1780         NCR5380_transfer_pio(host, &phase, &len, &msgptr);
1781
1782         /*
1783          * If we got here, and the command completed successfully,
1784          * we're about to go into bus free state.
1785          */
1786
1787         return len ? -1 : 0;
1788 }
1789
1790 #if defined(REAL_DMA) || defined(PSEUDO_DMA) || defined (REAL_DMA_POLL)
1791 /* 
1792  * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, 
1793  *      unsigned char *phase, int *count, unsigned char **data)
1794  *
1795  * Purpose : transfers data in given phase using either real
1796  *      or pseudo DMA.
1797  *
1798  * Inputs : instance - instance of driver, *phase - pointer to 
1799  *      what phase is expected, *count - pointer to number of 
1800  *      bytes to transfer, **data - pointer to data pointer.
1801  * 
1802  * Returns : -1 when different phase is entered without transferring
1803  *      maximum number of bytes, 0 if all bytes or transferred or exit
1804  *      is in same phase.
1805  *
1806  *      Also, *phase, *count, *data are modified in place.
1807  *
1808  *      Locks: io_request lock held by caller
1809  */
1810
1811
1812 static int NCR5380_transfer_dma(struct Scsi_Host *instance, unsigned char *phase, int *count, unsigned char **data) {
1813         NCR5380_local_declare();
1814         register int c = *count;
1815         register unsigned char p = *phase;
1816         register unsigned char *d = *data;
1817         unsigned char tmp;
1818         int foo;
1819 #if defined(REAL_DMA_POLL)
1820         int cnt, toPIO;
1821         unsigned char saved_data = 0, overrun = 0, residue;
1822 #endif
1823
1824         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1825
1826         NCR5380_setup(instance);
1827
1828         if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1829                 *phase = tmp;
1830                 return -1;
1831         }
1832 #if defined(REAL_DMA) || defined(REAL_DMA_POLL)
1833 #ifdef READ_OVERRUNS
1834         if (p & SR_IO) {
1835                 c -= 2;
1836         }
1837 #endif
1838         dprintk(NDEBUG_DMA, ("scsi%d : initializing DMA channel %d for %s, %d bytes %s %0x\n", instance->host_no, instance->dma_channel, (p & SR_IO) ? "reading" : "writing", c, (p & SR_IO) ? "to" : "from", (unsigned) d));
1839         hostdata->dma_len = (p & SR_IO) ? NCR5380_dma_read_setup(instance, d, c) : NCR5380_dma_write_setup(instance, d, c);
1840 #endif
1841
1842         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1843
1844 #ifdef REAL_DMA
1845         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1846 #elif defined(REAL_DMA_POLL)
1847         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1848 #else
1849         /*
1850          * Note : on my sample board, watch-dog timeouts occurred when interrupts
1851          * were not disabled for the duration of a single DMA transfer, from 
1852          * before the setting of DMA mode to after transfer of the last byte.
1853          */
1854
1855 #if defined(PSEUDO_DMA) && defined(UNSAFE)
1856         spin_unlock_irq(instance->host_lock);
1857 #endif
1858         /* KLL May need eop and parity in 53c400 */
1859         if (hostdata->flags & FLAG_NCR53C400)
1860                 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE |
1861                                 MR_ENABLE_PAR_CHECK | MR_ENABLE_PAR_INTR |
1862                                 MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1863         else
1864                 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1865 #endif                          /* def REAL_DMA */
1866
1867         dprintk(NDEBUG_DMA, ("scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG)));
1868
1869         /* 
1870          *      On the PAS16 at least I/O recovery delays are not needed here.
1871          *      Everyone else seems to want them.
1872          */
1873
1874         if (p & SR_IO) {
1875                 io_recovery_delay(1);
1876                 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1877         } else {
1878                 io_recovery_delay(1);
1879                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1880                 io_recovery_delay(1);
1881                 NCR5380_write(START_DMA_SEND_REG, 0);
1882                 io_recovery_delay(1);
1883         }
1884
1885 #if defined(REAL_DMA_POLL)
1886         do {
1887                 tmp = NCR5380_read(BUS_AND_STATUS_REG);
1888         } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER)));
1889
1890 /*
1891    At this point, either we've completed DMA, or we have a phase mismatch,
1892    or we've unexpectedly lost BUSY (which is a real error).
1893
1894    For write DMAs, we want to wait until the last byte has been
1895    transferred out over the bus before we turn off DMA mode.  Alas, there
1896    seems to be no terribly good way of doing this on a 5380 under all
1897    conditions.  For non-scatter-gather operations, we can wait until REQ
1898    and ACK both go false, or until a phase mismatch occurs.  Gather-writes
1899    are nastier, since the device will be expecting more data than we
1900    are prepared to send it, and REQ will remain asserted.  On a 53C8[01] we
1901    could test LAST BIT SENT to assure transfer (I imagine this is precisely
1902    why this signal was added to the newer chips) but on the older 538[01]
1903    this signal does not exist.  The workaround for this lack is a watchdog;
1904    we bail out of the wait-loop after a modest amount of wait-time if
1905    the usual exit conditions are not met.  Not a terribly clean or
1906    correct solution :-%
1907
1908    Reads are equally tricky due to a nasty characteristic of the NCR5380.
1909    If the chip is in DMA mode for an READ, it will respond to a target's
1910    REQ by latching the SCSI data into the INPUT DATA register and asserting
1911    ACK, even if it has _already_ been notified by the DMA controller that
1912    the current DMA transfer has completed!  If the NCR5380 is then taken
1913    out of DMA mode, this already-acknowledged byte is lost.
1914
1915    This is not a problem for "one DMA transfer per command" reads, because
1916    the situation will never arise... either all of the data is DMA'ed
1917    properly, or the target switches to MESSAGE IN phase to signal a
1918    disconnection (either operation bringing the DMA to a clean halt).
1919    However, in order to handle scatter-reads, we must work around the
1920    problem.  The chosen fix is to DMA N-2 bytes, then check for the
1921    condition before taking the NCR5380 out of DMA mode.  One or two extra
1922    bytes are transferred via PIO as necessary to fill out the original
1923    request.
1924  */
1925
1926         if (p & SR_IO) {
1927 #ifdef READ_OVERRUNS
1928                 udelay(10);
1929                 if (((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == (BASR_PHASE_MATCH | BASR_ACK))) {
1930                         saved_data = NCR5380_read(INPUT_DATA_REGISTER);
1931                         overrun = 1;
1932                 }
1933 #endif
1934         } else {
1935                 int limit = 100;
1936                 while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) {
1937                         if (!(tmp & BASR_PHASE_MATCH))
1938                                 break;
1939                         if (--limit < 0)
1940                                 break;
1941                 }
1942         }
1943
1944         dprintk(NDEBUG_DMA, ("scsi%d : polled DMA transfer complete, basr 0x%X, sr 0x%X\n", instance->host_no, tmp, NCR5380_read(STATUS_REG)));
1945
1946         NCR5380_write(MODE_REG, MR_BASE);
1947         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1948
1949         residue = NCR5380_dma_residual(instance);
1950         c -= residue;
1951         *count -= c;
1952         *data += c;
1953         *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
1954
1955 #ifdef READ_OVERRUNS
1956         if (*phase == p && (p & SR_IO) && residue == 0) {
1957                 if (overrun) {
1958                         dprintk(NDEBUG_DMA, ("Got an input overrun, using saved byte\n"));
1959                         **data = saved_data;
1960                         *data += 1;
1961                         *count -= 1;
1962                         cnt = toPIO = 1;
1963                 } else {
1964                         printk("No overrun??\n");
1965                         cnt = toPIO = 2;
1966                 }
1967                 dprintk(NDEBUG_DMA, ("Doing %d-byte PIO to 0x%X\n", cnt, *data));
1968                 NCR5380_transfer_pio(instance, phase, &cnt, data);
1969                 *count -= toPIO - cnt;
1970         }
1971 #endif
1972
1973         dprintk(NDEBUG_DMA, ("Return with data ptr = 0x%X, count %d, last 0x%X, next 0x%X\n", *data, *count, *(*data + *count - 1), *(*data + *count)));
1974         return 0;
1975
1976 #elif defined(REAL_DMA)
1977         return 0;
1978 #else                           /* defined(REAL_DMA_POLL) */
1979         if (p & SR_IO) {
1980 #ifdef DMA_WORKS_RIGHT
1981                 foo = NCR5380_pread(instance, d, c);
1982 #else
1983                 int diff = 1;
1984                 if (hostdata->flags & FLAG_NCR53C400) {
1985                         diff = 0;
1986                 }
1987                 if (!(foo = NCR5380_pread(instance, d, c - diff))) {
1988                         /*
1989                          * We can't disable DMA mode after successfully transferring 
1990                          * what we plan to be the last byte, since that would open up
1991                          * a race condition where if the target asserted REQ before 
1992                          * we got the DMA mode reset, the NCR5380 would have latched
1993                          * an additional byte into the INPUT DATA register and we'd
1994                          * have dropped it.
1995                          * 
1996                          * The workaround was to transfer one fewer bytes than we 
1997                          * intended to with the pseudo-DMA read function, wait for 
1998                          * the chip to latch the last byte, read it, and then disable
1999                          * pseudo-DMA mode.
2000                          * 
2001                          * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
2002                          * REQ is deasserted when ACK is asserted, and not reasserted
2003                          * until ACK goes false.  Since the NCR5380 won't lower ACK
2004                          * until DACK is asserted, which won't happen unless we twiddle
2005                          * the DMA port or we take the NCR5380 out of DMA mode, we 
2006                          * can guarantee that we won't handshake another extra 
2007                          * byte.
2008                          */
2009
2010                         if (!(hostdata->flags & FLAG_NCR53C400)) {
2011                                 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ));
2012                                 /* Wait for clean handshake */
2013                                 while (NCR5380_read(STATUS_REG) & SR_REQ);
2014                                 d[c - 1] = NCR5380_read(INPUT_DATA_REG);
2015                         }
2016                 }
2017 #endif
2018         } else {
2019 #ifdef DMA_WORKS_RIGHT
2020                 foo = NCR5380_pwrite(instance, d, c);
2021 #else
2022                 int timeout;
2023                 dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c));
2024                 if (!(foo = NCR5380_pwrite(instance, d, c))) {
2025                         /*
2026                          * Wait for the last byte to be sent.  If REQ is being asserted for 
2027                          * the byte we're interested, we'll ACK it and it will go false.  
2028                          */
2029                         if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) {
2030                                 timeout = 20000;
2031                                 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH));
2032
2033                                 if (!timeout)
2034                                         dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no));
2035
2036                                 if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) {
2037                                         hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT;
2038                                         if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) {
2039                                                 hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT;
2040                                                 dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no));
2041                                         }
2042                                 }
2043                         } else {
2044                                 dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n"));
2045                                 while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT));
2046                                 dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n"));
2047                         }
2048                 }
2049 #endif
2050         }
2051         NCR5380_write(MODE_REG, MR_BASE);
2052         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2053
2054         if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) {
2055                 dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n"));
2056                 if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) {
2057                         dprintk(NDEBUG_C400_PWRITE, ("53C400w:    got it, reading reset interrupt reg\n"));
2058                         NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2059                 } else {
2060                         printk("53C400w:    IRQ NOT THERE!\n");
2061                 }
2062         }
2063         *data = d + c;
2064         *count = 0;
2065         *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
2066 #if defined(PSEUDO_DMA) && defined(UNSAFE)
2067         spin_lock_irq(instance->host_lock);
2068 #endif                          /* defined(REAL_DMA_POLL) */
2069         return foo;
2070 #endif                          /* def REAL_DMA */
2071 }
2072 #endif                          /* defined(REAL_DMA) | defined(PSEUDO_DMA) */
2073
2074 /*
2075  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
2076  *
2077  * Purpose : run through the various SCSI phases and do as the target 
2078  *      directs us to.  Operates on the currently connected command, 
2079  *      instance->connected.
2080  *
2081  * Inputs : instance, instance for which we are doing commands
2082  *
2083  * Side effects : SCSI things happen, the disconnected queue will be 
2084  *      modified if a command disconnects, *instance->connected will
2085  *      change.
2086  *
2087  * XXX Note : we need to watch for bus free or a reset condition here 
2088  *      to recover from an unexpected bus free condition.
2089  *
2090  * Locks: io_request_lock held by caller in IRQ mode
2091  */
2092
2093 static void NCR5380_information_transfer(struct Scsi_Host *instance) {
2094         NCR5380_local_declare();
2095         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata;
2096         unsigned char msgout = NOP;
2097         int sink = 0;
2098         int len;
2099 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2100         int transfersize;
2101 #endif
2102         unsigned char *data;
2103         unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2104         Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2105         /* RvC: we need to set the end of the polling time */
2106         unsigned long poll_time = jiffies + USLEEP_POLL;
2107
2108         NCR5380_setup(instance);
2109
2110         while (1) {
2111                 tmp = NCR5380_read(STATUS_REG);
2112                 /* We only have a valid SCSI phase when REQ is asserted */
2113                 if (tmp & SR_REQ) {
2114                         phase = (tmp & PHASE_MASK);
2115                         if (phase != old_phase) {
2116                                 old_phase = phase;
2117                                 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
2118                         }
2119                         if (sink && (phase != PHASE_MSGOUT)) {
2120                                 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2121
2122                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
2123                                 while (NCR5380_read(STATUS_REG) & SR_REQ);
2124                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2125                                 sink = 0;
2126                                 continue;
2127                         }
2128                         switch (phase) {
2129                         case PHASE_DATAIN:
2130                         case PHASE_DATAOUT:
2131 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2132                                 printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no);
2133                                 sink = 1;
2134                                 do_abort(instance);
2135                                 cmd->result = DID_ERROR << 16;
2136                                 cmd->scsi_done(cmd);
2137                                 return;
2138 #endif
2139                                 /* 
2140                                  * If there is no room left in the current buffer in the
2141                                  * scatter-gather list, move onto the next one.
2142                                  */
2143
2144                                 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2145                                         ++cmd->SCp.buffer;
2146                                         --cmd->SCp.buffers_residual;
2147                                         cmd->SCp.this_residual = cmd->SCp.buffer->length;
2148                                         cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2149                                         dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual));
2150                                 }
2151                                 /*
2152                                  * The preferred transfer method is going to be 
2153                                  * PSEUDO-DMA for systems that are strictly PIO,
2154                                  * since we can let the hardware do the handshaking.
2155                                  *
2156                                  * For this to work, we need to know the transfersize
2157                                  * ahead of time, since the pseudo-DMA code will sit
2158                                  * in an unconditional loop.
2159                                  */
2160
2161 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2162                                 /* KLL
2163                                  * PSEUDO_DMA is defined here. If this is the g_NCR5380
2164                                  * driver then it will always be defined, so the
2165                                  * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base
2166                                  * NCR5380 case.  I think this is a fairly clean solution.
2167                                  * We supplement these 2 if's with the flag.
2168                                  */
2169 #ifdef NCR5380_dma_xfer_len
2170                                 if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) {
2171 #else
2172                                 transfersize = cmd->transfersize;
2173
2174 #ifdef LIMIT_TRANSFERSIZE       /* If we have problems with interrupt service */
2175                                 if (transfersize > 512)
2176                                         transfersize = 512;
2177 #endif                          /* LIMIT_TRANSFERSIZE */
2178
2179                                 if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) {
2180                                         /* Limit transfers to 32K, for xx400 & xx406
2181                                          * pseudoDMA that transfers in 128 bytes blocks. */
2182                                         if (transfersize > 32 * 1024)
2183                                                 transfersize = 32 * 1024;
2184 #endif
2185                                         len = transfersize;
2186                                         if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) {
2187                                                 /*
2188                                                  * If the watchdog timer fires, all future accesses to this
2189                                                  * device will use the polled-IO.
2190                                                  */
2191                                                 scmd_printk(KERN_INFO, cmd,
2192                                                             "switching to slow handshake\n");
2193                                                 cmd->device->borken = 1;
2194                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2195                                                 sink = 1;
2196                                                 do_abort(instance);
2197                                                 cmd->result = DID_ERROR << 16;
2198                                                 cmd->scsi_done(cmd);
2199                                                 /* XXX - need to source or sink data here, as appropriate */
2200                                         } else
2201                                                 cmd->SCp.this_residual -= transfersize - len;
2202                                 } else
2203 #endif                          /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */
2204                                         NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **)
2205                                                              &cmd->SCp.ptr);
2206                                 break;
2207                         case PHASE_MSGIN:
2208                                 len = 1;
2209                                 data = &tmp;
2210                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2211                                 cmd->SCp.Message = tmp;
2212
2213                                 switch (tmp) {
2214                                         /*
2215                                          * Linking lets us reduce the time required to get the 
2216                                          * next command out to the device, hopefully this will
2217                                          * mean we don't waste another revolution due to the delays
2218                                          * required by ARBITRATION and another SELECTION.
2219                                          *
2220                                          * In the current implementation proposal, low level drivers
2221                                          * merely have to start the next command, pointed to by 
2222                                          * next_link, done() is called as with unlinked commands.
2223                                          */
2224 #ifdef LINKED
2225                                 case LINKED_CMD_COMPLETE:
2226                                 case LINKED_FLG_CMD_COMPLETE:
2227                                         /* Accept message by clearing ACK */
2228                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2229                                         dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun));
2230                                         /* 
2231                                          * Sanity check : A linked command should only terminate with
2232                                          * one of these messages if there are more linked commands
2233                                          * available.
2234                                          */
2235                                         if (!cmd->next_link) {
2236                                                 printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun);
2237                                                 sink = 1;
2238                                                 do_abort(instance);
2239                                                 return;
2240                                         }
2241                                         initialize_SCp(cmd->next_link);
2242                                         /* The next command is still part of this process */
2243                                         cmd->next_link->tag = cmd->tag;
2244                                         cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2245                                         dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked request done, calling scsi_done().\n", instance->host_no, cmd->device->id, cmd->device->lun));
2246                                         collect_stats(hostdata, cmd);
2247                                         cmd->scsi_done(cmd);
2248                                         cmd = hostdata->connected;
2249                                         break;
2250 #endif                          /* def LINKED */
2251                                 case ABORT:
2252                                 case COMMAND_COMPLETE:
2253                                         /* Accept message by clearing ACK */
2254                                         sink = 1;
2255                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2256                                         hostdata->connected = NULL;
2257                                         dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun));
2258                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2259
2260                                         /* 
2261                                          * I'm not sure what the correct thing to do here is : 
2262                                          * 
2263                                          * If the command that just executed is NOT a request 
2264                                          * sense, the obvious thing to do is to set the result
2265                                          * code to the values of the stored parameters.
2266                                          * 
2267                                          * If it was a REQUEST SENSE command, we need some way 
2268                                          * to differentiate between the failure code of the original
2269                                          * and the failure code of the REQUEST sense - the obvious
2270                                          * case is success, where we fall through and leave the result
2271                                          * code unchanged.
2272                                          * 
2273                                          * The non-obvious place is where the REQUEST SENSE failed 
2274                                          */
2275
2276                                         if (cmd->cmnd[0] != REQUEST_SENSE)
2277                                                 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2278                                         else if (status_byte(cmd->SCp.Status) != GOOD)
2279                                                 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2280
2281 #ifdef AUTOSENSE
2282                                         if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2283                                                 hostdata->ses.cmd_len) {
2284                                                 scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2285                                                 hostdata->ses.cmd_len = 0 ;
2286                                         }
2287
2288                                         if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2289                                                 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2290
2291                                                 dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no));
2292
2293                                                 LIST(cmd, hostdata->issue_queue);
2294                                                 cmd->host_scribble = (unsigned char *)
2295                                                     hostdata->issue_queue;
2296                                                 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2297                                                 dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no));
2298                                         } else
2299 #endif                          /* def AUTOSENSE */
2300                                         {
2301                                                 collect_stats(hostdata, cmd);
2302                                                 cmd->scsi_done(cmd);
2303                                         }
2304
2305                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2306                                         /* 
2307                                          * Restore phase bits to 0 so an interrupted selection, 
2308                                          * arbitration can resume.
2309                                          */
2310                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2311
2312                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2313                                                 barrier();
2314                                         return;
2315                                 case MESSAGE_REJECT:
2316                                         /* Accept message by clearing ACK */
2317                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2318                                         switch (hostdata->last_message) {
2319                                         case HEAD_OF_QUEUE_TAG:
2320                                         case ORDERED_QUEUE_TAG:
2321                                         case SIMPLE_QUEUE_TAG:
2322                                                 cmd->device->simple_tags = 0;
2323                                                 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2324                                                 break;
2325                                         default:
2326                                                 break;
2327                                         }
2328                                 case DISCONNECT:{
2329                                                 /* Accept message by clearing ACK */
2330                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2331                                                 cmd->device->disconnect = 1;
2332                                                 LIST(cmd, hostdata->disconnected_queue);
2333                                                 cmd->host_scribble = (unsigned char *)
2334                                                     hostdata->disconnected_queue;
2335                                                 hostdata->connected = NULL;
2336                                                 hostdata->disconnected_queue = cmd;
2337                                                 dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d lun %d was moved from connected to" "  the disconnected_queue\n", instance->host_no, cmd->device->id, cmd->device->lun));
2338                                                 /* 
2339                                                  * Restore phase bits to 0 so an interrupted selection, 
2340                                                  * arbitration can resume.
2341                                                  */
2342                                                 NCR5380_write(TARGET_COMMAND_REG, 0);
2343
2344                                                 /* Enable reselect interrupts */
2345                                                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2346                                                 /* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/
2347                                                 /* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */
2348                                                 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2349                                                         barrier();
2350                                                 return;
2351                                         }
2352                                         /* 
2353                                          * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2354                                          * operation, in violation of the SCSI spec so we can safely 
2355                                          * ignore SAVE/RESTORE pointers calls.
2356                                          *
2357                                          * Unfortunately, some disks violate the SCSI spec and 
2358                                          * don't issue the required SAVE_POINTERS message before
2359                                          * disconnecting, and we have to break spec to remain 
2360                                          * compatible.
2361                                          */
2362                                 case SAVE_POINTERS:
2363                                 case RESTORE_POINTERS:
2364                                         /* Accept message by clearing ACK */
2365                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2366                                         break;
2367                                 case EXTENDED_MESSAGE:
2368 /* 
2369  * Extended messages are sent in the following format :
2370  * Byte         
2371  * 0            EXTENDED_MESSAGE == 1
2372  * 1            length (includes one byte for code, doesn't 
2373  *              include first two bytes)
2374  * 2            code
2375  * 3..length+1  arguments
2376  *
2377  * Start the extended message buffer with the EXTENDED_MESSAGE
2378  * byte, since spi_print_msg() wants the whole thing.  
2379  */
2380                                         extended_msg[0] = EXTENDED_MESSAGE;
2381                                         /* Accept first byte by clearing ACK */
2382                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2383                                         dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no));
2384
2385                                         len = 2;
2386                                         data = extended_msg + 1;
2387                                         phase = PHASE_MSGIN;
2388                                         NCR5380_transfer_pio(instance, &phase, &len, &data);
2389
2390                                         dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2]));
2391
2392                                         if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) {
2393                                                 /* Accept third byte by clearing ACK */
2394                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2395                                                 len = extended_msg[1] - 1;
2396                                                 data = extended_msg + 3;
2397                                                 phase = PHASE_MSGIN;
2398
2399                                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2400                                                 dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len));
2401
2402                                                 switch (extended_msg[2]) {
2403                                                 case EXTENDED_SDTR:
2404                                                 case EXTENDED_WDTR:
2405                                                 case EXTENDED_MODIFY_DATA_POINTER:
2406                                                 case EXTENDED_EXTENDED_IDENTIFY:
2407                                                         tmp = 0;
2408                                                 }
2409                                         } else if (len) {
2410                                                 printk("scsi%d: error receiving extended message\n", instance->host_no);
2411                                                 tmp = 0;
2412                                         } else {
2413                                                 printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]);
2414                                                 tmp = 0;
2415                                         }
2416                                         /* Fall through to reject message */
2417
2418                                         /* 
2419                                          * If we get something weird that we aren't expecting, 
2420                                          * reject it.
2421                                          */
2422                                 default:
2423                                         if (!tmp) {
2424                                                 printk("scsi%d: rejecting message ", instance->host_no);
2425                                                 spi_print_msg(extended_msg);
2426                                                 printk("\n");
2427                                         } else if (tmp != EXTENDED_MESSAGE)
2428                                                 scmd_printk(KERN_INFO, cmd,
2429                                                         "rejecting unknown message %02x\n",tmp);
2430                                         else
2431                                                 scmd_printk(KERN_INFO, cmd,
2432                                                         "rejecting unknown extended message code %02x, length %d\n", extended_msg[1], extended_msg[0]);
2433
2434                                         msgout = MESSAGE_REJECT;
2435                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2436                                         break;
2437                                 }       /* switch (tmp) */
2438                                 break;
2439                         case PHASE_MSGOUT:
2440                                 len = 1;
2441                                 data = &msgout;
2442                                 hostdata->last_message = msgout;
2443                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2444                                 if (msgout == ABORT) {
2445                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2446                                         hostdata->connected = NULL;
2447                                         cmd->result = DID_ERROR << 16;
2448                                         collect_stats(hostdata, cmd);
2449                                         cmd->scsi_done(cmd);
2450                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2451                                         return;
2452                                 }
2453                                 msgout = NOP;
2454                                 break;
2455                         case PHASE_CMDOUT:
2456                                 len = cmd->cmd_len;
2457                                 data = cmd->cmnd;
2458                                 /* 
2459                                  * XXX for performance reasons, on machines with a 
2460                                  * PSEUDO-DMA architecture we should probably 
2461                                  * use the dma transfer function.  
2462                                  */
2463                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2464                                 if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) {
2465                                         NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2466                                         dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2467                                         return;
2468                                 }
2469                                 break;
2470                         case PHASE_STATIN:
2471                                 len = 1;
2472                                 data = &tmp;
2473                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2474                                 cmd->SCp.Status = tmp;
2475                                 break;
2476                         default:
2477                                 printk("scsi%d : unknown phase\n", instance->host_no);
2478                                 NCR5380_dprint(NDEBUG_ALL, instance);
2479                         }       /* switch(phase) */
2480                 }               /* if (tmp * SR_REQ) */
2481                 else {
2482                         /* RvC: go to sleep if polling time expired
2483                          */
2484                         if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) {
2485                                 NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2486                                 dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2487                                 return;
2488                         }
2489                 }
2490         }                       /* while (1) */
2491 }
2492
2493 /*
2494  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2495  *
2496  * Purpose : does reselection, initializing the instance->connected 
2497  *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q 
2498  *      nexus has been reestablished,
2499  *      
2500  * Inputs : instance - this instance of the NCR5380.
2501  *
2502  * Locks: io_request_lock held by caller if IRQ driven
2503  */
2504
2505 static void NCR5380_reselect(struct Scsi_Host *instance) {
2506         NCR5380_local_declare();
2507         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)
2508          instance->hostdata;
2509         unsigned char target_mask;
2510         unsigned char lun, phase;
2511         int len;
2512         unsigned char msg[3];
2513         unsigned char *data;
2514         Scsi_Cmnd *tmp = NULL, *prev;
2515         int abort = 0;
2516         NCR5380_setup(instance);
2517
2518         /*
2519          * Disable arbitration, etc. since the host adapter obviously
2520          * lost, and tell an interrupted NCR5380_select() to restart.
2521          */
2522
2523         NCR5380_write(MODE_REG, MR_BASE);
2524         hostdata->restart_select = 1;
2525
2526         target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2527         dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no));
2528
2529         /* 
2530          * At this point, we have detected that our SCSI ID is on the bus,
2531          * SEL is true and BSY was false for at least one bus settle delay
2532          * (400 ns).
2533          *
2534          * We must assert BSY ourselves, until the target drops the SEL
2535          * signal.
2536          */
2537
2538         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2539
2540         /* FIXME: timeout too long, must fail to workqueue */   
2541         if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0)
2542                 abort = 1;
2543                 
2544         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2545
2546         /*
2547          * Wait for target to go into MSGIN.
2548          * FIXME: timeout needed and fail to work queeu
2549          */
2550
2551         if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ))
2552                 abort = 1;
2553
2554         len = 1;
2555         data = msg;
2556         phase = PHASE_MSGIN;
2557         NCR5380_transfer_pio(instance, &phase, &len, &data);
2558
2559         if (!(msg[0] & 0x80)) {
2560                 printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no);
2561                 spi_print_msg(msg);
2562                 abort = 1;
2563         } else {
2564                 /* Accept message by clearing ACK */
2565                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2566                 lun = (msg[0] & 0x07);
2567
2568                 /* 
2569                  * We need to add code for SCSI-II to track which devices have
2570                  * I_T_L_Q nexuses established, and which have simple I_T_L
2571                  * nexuses so we can chose to do additional data transfer.
2572                  */
2573
2574                 /* 
2575                  * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we 
2576                  * just reestablished, and remove it from the disconnected queue.
2577                  */
2578
2579
2580                 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
2581                         if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2582                             ) {
2583                                 if (prev) {
2584                                         REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
2585                                         prev->host_scribble = tmp->host_scribble;
2586                                 } else {
2587                                         REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble);
2588                                         hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble;
2589                                 }
2590                                 tmp->host_scribble = NULL;
2591                                 break;
2592                         }
2593                 if (!tmp) {
2594                         printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun);
2595                         /* 
2596                          * Since we have an established nexus that we can't do anything with,
2597                          * we must abort it.  
2598                          */
2599                         abort = 1;
2600                 }
2601         }
2602
2603         if (abort) {
2604                 do_abort(instance);
2605         } else {
2606                 hostdata->connected = tmp;
2607                 dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag));
2608         }
2609 }
2610
2611 /*
2612  * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
2613  *
2614  * Purpose : called by interrupt handler when DMA finishes or a phase
2615  *      mismatch occurs (which would finish the DMA transfer).  
2616  *
2617  * Inputs : instance - this instance of the NCR5380.
2618  *
2619  * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L
2620  *      nexus has been reestablished, on failure NULL is returned.
2621  */
2622
2623 #ifdef REAL_DMA
2624 static void NCR5380_dma_complete(NCR5380_instance * instance) {
2625         NCR5380_local_declare();
2626         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2627         int transferred;
2628         NCR5380_setup(instance);
2629
2630         /*
2631          * XXX this might not be right.
2632          *
2633          * Wait for final byte to transfer, ie wait for ACK to go false.
2634          *
2635          * We should use the Last Byte Sent bit, unfortunately this is 
2636          * not available on the 5380/5381 (only the various CMOS chips)
2637          *
2638          * FIXME: timeout, and need to handle long timeout/irq case
2639          */
2640
2641         NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ);
2642
2643         NCR5380_write(MODE_REG, MR_BASE);
2644         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2645
2646         /*
2647          * The only places we should see a phase mismatch and have to send
2648          * data from the same set of pointers will be the data transfer
2649          * phases.  So, residual, requested length are only important here.
2650          */
2651
2652         if (!(hostdata->connected->SCp.phase & SR_CD)) {
2653                 transferred = instance->dmalen - NCR5380_dma_residual();
2654                 hostdata->connected->SCp.this_residual -= transferred;
2655                 hostdata->connected->SCp.ptr += transferred;
2656         }
2657 }
2658 #endif                          /* def REAL_DMA */
2659
2660 /*
2661  * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2662  *
2663  * Purpose : abort a command
2664  *
2665  * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the 
2666  *      host byte of the result field to, if zero DID_ABORTED is 
2667  *      used.
2668  *
2669  * Returns : 0 - success, -1 on failure.
2670  *
2671  *      XXX - there is no way to abort the command that is currently 
2672  *      connected, you have to wait for it to complete.  If this is 
2673  *      a problem, we could implement longjmp() / setjmp(), setjmp()
2674  *      called where the loop started in NCR5380_main().
2675  *
2676  * Locks: host lock taken by caller
2677  */
2678
2679 static int NCR5380_abort(Scsi_Cmnd * cmd) {
2680         NCR5380_local_declare();
2681         struct Scsi_Host *instance = cmd->device->host;
2682         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2683         Scsi_Cmnd *tmp, **prev;
2684         
2685         printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no);
2686         scsi_print_command(cmd);
2687
2688         NCR5380_print_status(instance);
2689
2690         NCR5380_setup(instance);
2691
2692         dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no));
2693         dprintk(NDEBUG_ABORT, ("        basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)));
2694
2695 #if 0
2696 /*
2697  * Case 1 : If the command is the currently executing command, 
2698  * we'll set the aborted flag and return control so that 
2699  * information transfer routine can exit cleanly.
2700  */
2701
2702         if (hostdata->connected == cmd) {
2703                 dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no));
2704                 hostdata->aborted = 1;
2705 /*
2706  * We should perform BSY checking, and make sure we haven't slipped
2707  * into BUS FREE.
2708  */
2709
2710                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN);
2711 /* 
2712  * Since we can't change phases until we've completed the current 
2713  * handshake, we have to source or sink a byte of data if the current
2714  * phase is not MSGOUT.
2715  */
2716
2717 /* 
2718  * Return control to the executing NCR drive so we can clear the
2719  * aborted flag and get back into our main loop.
2720  */
2721
2722                 return 0;
2723         }
2724 #endif
2725
2726 /* 
2727  * Case 2 : If the command hasn't been issued yet, we simply remove it 
2728  *          from the issue queue.
2729  */
2730  
2731         dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no));
2732         for (prev = (Scsi_Cmnd **) & (hostdata->issue_queue), tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
2733                 if (cmd == tmp) {
2734                         REMOVE(5, *prev, tmp, tmp->host_scribble);
2735                         (*prev) = (Scsi_Cmnd *) tmp->host_scribble;
2736                         tmp->host_scribble = NULL;
2737                         tmp->result = DID_ABORT << 16;
2738                         dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no));
2739                         tmp->scsi_done(tmp);
2740                         return SUCCESS;
2741                 }
2742 #if (NDEBUG  & NDEBUG_ABORT)
2743         /* KLL */
2744                 else if (prev == tmp)
2745                         printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no);
2746 #endif
2747
2748 /* 
2749  * Case 3 : If any commands are connected, we're going to fail the abort
2750  *          and let the high level SCSI driver retry at a later time or 
2751  *          issue a reset.
2752  *
2753  *          Timeouts, and therefore aborted commands, will be highly unlikely
2754  *          and handling them cleanly in this situation would make the common
2755  *          case of noresets less efficient, and would pollute our code.  So,
2756  *          we fail.
2757  */
2758
2759         if (hostdata->connected) {
2760                 dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no));
2761                 return FAILED;
2762         }
2763 /*
2764  * Case 4: If the command is currently disconnected from the bus, and 
2765  *      there are no connected commands, we reconnect the I_T_L or 
2766  *      I_T_L_Q nexus associated with it, go into message out, and send 
2767  *      an abort message.
2768  *
2769  * This case is especially ugly. In order to reestablish the nexus, we
2770  * need to call NCR5380_select().  The easiest way to implement this 
2771  * function was to abort if the bus was busy, and let the interrupt
2772  * handler triggered on the SEL for reselect take care of lost arbitrations
2773  * where necessary, meaning interrupts need to be enabled.
2774  *
2775  * When interrupts are enabled, the queues may change - so we 
2776  * can't remove it from the disconnected queue before selecting it
2777  * because that could cause a failure in hashing the nexus if that 
2778  * device reselected.
2779  * 
2780  * Since the queues may change, we can't use the pointers from when we
2781  * first locate it.
2782  *
2783  * So, we must first locate the command, and if NCR5380_select()
2784  * succeeds, then issue the abort, relocate the command and remove
2785  * it from the disconnected queue.
2786  */
2787
2788         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble)
2789                 if (cmd == tmp) {
2790                         dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no));
2791
2792                         if (NCR5380_select(instance, cmd, (int) cmd->tag))
2793                                 return FAILED;
2794                         dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no));
2795
2796                         do_abort(instance);
2797
2798                         for (prev = (Scsi_Cmnd **) & (hostdata->disconnected_queue), tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
2799                                 if (cmd == tmp) {
2800                                         REMOVE(5, *prev, tmp, tmp->host_scribble);
2801                                         *prev = (Scsi_Cmnd *) tmp->host_scribble;
2802                                         tmp->host_scribble = NULL;
2803                                         tmp->result = DID_ABORT << 16;
2804                                         tmp->scsi_done(tmp);
2805                                         return SUCCESS;
2806                                 }
2807                 }
2808 /*
2809  * Case 5 : If we reached this point, the command was not found in any of 
2810  *          the queues.
2811  *
2812  * We probably reached this point because of an unlikely race condition
2813  * between the command completing successfully and the abortion code,
2814  * so we won't panic, but we will notify the user in case something really
2815  * broke.
2816  */
2817         printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n"
2818                         "         before abortion\n", instance->host_no);
2819         return FAILED;
2820 }
2821
2822
2823 /* 
2824  * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd)
2825  * 
2826  * Purpose : reset the SCSI bus.
2827  *
2828  * Returns : SUCCESS
2829  *
2830  * Locks: host lock taken by caller
2831  */
2832
2833 static int NCR5380_bus_reset(Scsi_Cmnd * cmd)
2834 {
2835         struct Scsi_Host *instance = cmd->device->host;
2836
2837         NCR5380_local_declare();
2838         NCR5380_setup(instance);
2839         NCR5380_print_status(instance);
2840
2841         spin_lock_irq(instance->host_lock);
2842         do_reset(instance);
2843         spin_unlock_irq(instance->host_lock);
2844
2845         return SUCCESS;
2846 }