parse errors in ifdefs
[linux-3.10.git] / drivers / scsi / NCR5380.c
1 /* 
2  * NCR 5380 generic driver routines.  These should make it *trivial*
3  *      to implement 5380 SCSI drivers under Linux with a non-trantor
4  *      architecture.
5  *
6  *      Note that these routines also work with NR53c400 family chips.
7  *
8  * Copyright 1993, Drew Eckhardt
9  *      Visionary Computing 
10  *      (Unix and Linux consulting and custom programming)
11  *      drew@colorado.edu
12  *      +1 (303) 666-5836
13  *
14  * DISTRIBUTION RELEASE 6. 
15  *
16  * For more information, please consult 
17  *
18  * NCR 5380 Family
19  * SCSI Protocol Controller
20  * Databook
21  *
22  * NCR Microelectronics
23  * 1635 Aeroplaza Drive
24  * Colorado Springs, CO 80916
25  * 1+ (719) 578-3400
26  * 1+ (800) 334-5454
27  */
28
29 /*
30  * $Log: NCR5380.c,v $
31
32  * Revision 1.10 1998/9/2       Alan Cox
33  *                              (alan@redhat.com)
34  * Fixed up the timer lockups reported so far. Things still suck. Looking 
35  * forward to 2.3 and per device request queues. Then it'll be possible to
36  * SMP thread this beast and improve life no end.
37  
38  * Revision 1.9  1997/7/27      Ronald van Cuijlenborg
39  *                              (ronald.van.cuijlenborg@tip.nl or nutty@dds.nl)
40  * (hopefully) fixed and enhanced USLEEP
41  * added support for DTC3181E card (for Mustek scanner)
42  *
43
44  * Revision 1.8                 Ingmar Baumgart
45  *                              (ingmar@gonzo.schwaben.de)
46  * added support for NCR53C400a card
47  *
48
49  * Revision 1.7  1996/3/2       Ray Van Tassle (rayvt@comm.mot.com)
50  * added proc_info
51  * added support needed for DTC 3180/3280
52  * fixed a couple of bugs
53  *
54
55  * Revision 1.5  1994/01/19  09:14:57  drew
56  * Fixed udelay() hack that was being used on DATAOUT phases
57  * instead of a proper wait for the final handshake.
58  *
59  * Revision 1.4  1994/01/19  06:44:25  drew
60  * *** empty log message ***
61  *
62  * Revision 1.3  1994/01/19  05:24:40  drew
63  * Added support for TCR LAST_BYTE_SENT bit.
64  *
65  * Revision 1.2  1994/01/15  06:14:11  drew
66  * REAL DMA support, bug fixes.
67  *
68  * Revision 1.1  1994/01/15  06:00:54  drew
69  * Initial revision
70  *
71  */
72
73 /*
74  * Further development / testing that should be done : 
75  * 1.  Cleanup the NCR5380_transfer_dma function and DMA operation complete
76  *     code so that everything does the same thing that's done at the 
77  *     end of a pseudo-DMA read operation.
78  *
79  * 2.  Fix REAL_DMA (interrupt driven, polled works fine) -
80  *     basically, transfer size needs to be reduced by one 
81  *     and the last byte read as is done with PSEUDO_DMA.
82  * 
83  * 4.  Test SCSI-II tagged queueing (I have no devices which support 
84  *      tagged queueing)
85  *
86  * 5.  Test linked command handling code after Eric is ready with 
87  *      the high level code.
88  */
89 #include <scsi/scsi_dbg.h>
90 #include <scsi/scsi_transport_spi.h>
91
92 #ifndef NDEBUG
93 #define NDEBUG 0
94 #endif
95 #ifndef NDEBUG_ABORT
96 #define NDEBUG_ABORT 0
97 #endif
98
99 #if (NDEBUG & NDEBUG_LISTS)
100 #define LIST(x,y) {printk("LINE:%d   Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); if ((x)==(y)) udelay(5); }
101 #define REMOVE(w,x,y,z) {printk("LINE:%d   Removing: %p->%p  %p->%p \n", __LINE__, (void*)(w), (void*)(x), (void*)(y), (void*)(z)); if ((x)==(y)) udelay(5); }
102 #else
103 #define LIST(x,y)
104 #define REMOVE(w,x,y,z)
105 #endif
106
107 #ifndef notyet
108 #undef LINKED
109 #undef REAL_DMA
110 #endif
111
112 #ifdef REAL_DMA_POLL
113 #undef READ_OVERRUNS
114 #define READ_OVERRUNS
115 #endif
116
117 #ifdef BOARD_REQUIRES_NO_DELAY
118 #define io_recovery_delay(x)
119 #else
120 #define io_recovery_delay(x)    udelay(x)
121 #endif
122
123 /*
124  * Design
125  *
126  * This is a generic 5380 driver.  To use it on a different platform, 
127  * one simply writes appropriate system specific macros (ie, data
128  * transfer - some PC's will use the I/O bus, 68K's must use 
129  * memory mapped) and drops this file in their 'C' wrapper.
130  *
131  * (Note from hch:  unfortunately it was not enough for the different
132  * m68k folks and instead of improving this driver they copied it
133  * and hacked it up for their needs.  As a consequence they lost
134  * most updates to this driver.  Maybe someone will fix all these
135  * drivers to use a common core one day..)
136  *
137  * As far as command queueing, two queues are maintained for 
138  * each 5380 in the system - commands that haven't been issued yet,
139  * and commands that are currently executing.  This means that an 
140  * unlimited number of commands may be queued, letting 
141  * more commands propagate from the higher driver levels giving higher 
142  * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported, 
143  * allowing multiple commands to propagate all the way to a SCSI-II device 
144  * while a command is already executing.
145  *
146  *
147  * Issues specific to the NCR5380 : 
148  *
149  * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead 
150  * piece of hardware that requires you to sit in a loop polling for 
151  * the REQ signal as long as you are connected.  Some devices are 
152  * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect 
153  * while doing long seek operations.
154  * 
155  * The workaround for this is to keep track of devices that have
156  * disconnected.  If the device hasn't disconnected, for commands that
157  * should disconnect, we do something like 
158  *
159  * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
160  * 
161  * Some tweaking of N and M needs to be done.  An algorithm based 
162  * on "time to data" would give the best results as long as short time
163  * to datas (ie, on the same track) were considered, however these 
164  * broken devices are the exception rather than the rule and I'd rather
165  * spend my time optimizing for the normal case.
166  *
167  * Architecture :
168  *
169  * At the heart of the design is a coroutine, NCR5380_main,
170  * which is started from a workqueue for each NCR5380 host in the
171  * system.  It attempts to establish I_T_L or I_T_L_Q nexuses by
172  * removing the commands from the issue queue and calling
173  * NCR5380_select() if a nexus is not established. 
174  *
175  * Once a nexus is established, the NCR5380_information_transfer()
176  * phase goes through the various phases as instructed by the target.
177  * if the target goes into MSG IN and sends a DISCONNECT message,
178  * the command structure is placed into the per instance disconnected
179  * queue, and NCR5380_main tries to find more work.  If the target is 
180  * idle for too long, the system will try to sleep.
181  *
182  * If a command has disconnected, eventually an interrupt will trigger,
183  * calling NCR5380_intr()  which will in turn call NCR5380_reselect
184  * to reestablish a nexus.  This will run main if necessary.
185  *
186  * On command termination, the done function will be called as 
187  * appropriate.
188  *
189  * SCSI pointers are maintained in the SCp field of SCSI command 
190  * structures, being initialized after the command is connected
191  * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
192  * Note that in violation of the standard, an implicit SAVE POINTERS operation
193  * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
194  */
195
196 /*
197  * Using this file :
198  * This file a skeleton Linux SCSI driver for the NCR 5380 series
199  * of chips.  To use it, you write an architecture specific functions 
200  * and macros and include this file in your driver.
201  *
202  * These macros control options : 
203  * AUTOPROBE_IRQ - if defined, the NCR5380_probe_irq() function will be 
204  *      defined.
205  * 
206  * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
207  *      for commands that return with a CHECK CONDITION status. 
208  *
209  * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
210  *      transceivers. 
211  *
212  * DONT_USE_INTR - if defined, never use interrupts, even if we probe or
213  *      override-configure an IRQ.
214  *
215  * LIMIT_TRANSFERSIZE - if defined, limit the pseudo-dma transfers to 512
216  *      bytes at a time.  Since interrupts are disabled by default during
217  *      these transfers, we might need this to give reasonable interrupt
218  *      service time if the transfer size gets too large.
219  *
220  * LINKED - if defined, linked commands are supported.
221  *
222  * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
223  *
224  * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
225  *
226  * REAL_DMA_POLL - if defined, REAL DMA is used but the driver doesn't
227  *      rely on phase mismatch and EOP interrupts to determine end 
228  *      of phase.
229  *
230  * UNSAFE - leave interrupts enabled during pseudo-DMA transfers.  You
231  *          only really want to use this if you're having a problem with
232  *          dropped characters during high speed communications, and even
233  *          then, you're going to be better off twiddling with transfersize
234  *          in the high level code.
235  *
236  * Defaults for these will be provided although the user may want to adjust 
237  * these to allocate CPU resources to the SCSI driver or "real" code.
238  * 
239  * USLEEP_SLEEP - amount of time, in jiffies, to sleep
240  *
241  * USLEEP_POLL - amount of time, in jiffies, to poll
242  *
243  * These macros MUST be defined :
244  * NCR5380_local_declare() - declare any local variables needed for your
245  *      transfer routines.
246  *
247  * NCR5380_setup(instance) - initialize any local variables needed from a given
248  *      instance of the host adapter for NCR5380_{read,write,pread,pwrite}
249  * 
250  * NCR5380_read(register)  - read from the specified register
251  *
252  * NCR5380_write(register, value) - write to the specific register 
253  *
254  * NCR5380_implementation_fields  - additional fields needed for this 
255  *      specific implementation of the NCR5380
256  *
257  * Either real DMA *or* pseudo DMA may be implemented
258  * REAL functions : 
259  * NCR5380_REAL_DMA should be defined if real DMA is to be used.
260  * Note that the DMA setup functions should return the number of bytes 
261  *      that they were able to program the controller for.
262  *
263  * Also note that generic i386/PC versions of these macros are 
264  *      available as NCR5380_i386_dma_write_setup,
265  *      NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
266  *
267  * NCR5380_dma_write_setup(instance, src, count) - initialize
268  * NCR5380_dma_read_setup(instance, dst, count) - initialize
269  * NCR5380_dma_residual(instance); - residual count
270  *
271  * PSEUDO functions :
272  * NCR5380_pwrite(instance, src, count)
273  * NCR5380_pread(instance, dst, count);
274  *
275  * The generic driver is initialized by calling NCR5380_init(instance),
276  * after setting the appropriate host specific fields and ID.  If the 
277  * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
278  * possible) function may be used.
279  */
280
281 static int do_abort(struct Scsi_Host *host);
282 static void do_reset(struct Scsi_Host *host);
283
284 /*
285  *      initialize_SCp          -       init the scsi pointer field
286  *      @cmd: command block to set up
287  *
288  *      Set up the internal fields in the SCSI command.
289  */
290
291 static __inline__ void initialize_SCp(Scsi_Cmnd * cmd)
292 {
293         /* 
294          * Initialize the Scsi Pointer field so that all of the commands in the 
295          * various queues are valid.
296          */
297
298         if (cmd->use_sg) {
299                 cmd->SCp.buffer = (struct scatterlist *) cmd->request_buffer;
300                 cmd->SCp.buffers_residual = cmd->use_sg - 1;
301                 cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+
302                                cmd->SCp.buffer->offset;
303                 cmd->SCp.this_residual = cmd->SCp.buffer->length;
304         } else {
305                 cmd->SCp.buffer = NULL;
306                 cmd->SCp.buffers_residual = 0;
307                 cmd->SCp.ptr = (char *) cmd->request_buffer;
308                 cmd->SCp.this_residual = cmd->request_bufflen;
309         }
310 }
311
312 /**
313  *      NCR5380_poll_politely   -       wait for NCR5380 status bits
314  *      @instance: controller to poll
315  *      @reg: 5380 register to poll
316  *      @bit: Bitmask to check
317  *      @val: Value required to exit
318  *
319  *      Polls the NCR5380 in a reasonably efficient manner waiting for
320  *      an event to occur, after a short quick poll we begin giving the
321  *      CPU back in non IRQ contexts
322  *
323  *      Returns the value of the register or a negative error code.
324  */
325  
326 static int NCR5380_poll_politely(struct Scsi_Host *instance, int reg, int bit, int val, int t)
327 {
328         NCR5380_local_declare();
329         int n = 500;            /* At about 8uS a cycle for the cpu access */
330         unsigned long end = jiffies + t;
331         int r;
332         
333         NCR5380_setup(instance);
334
335         while( n-- > 0)
336         {
337                 r = NCR5380_read(reg);
338                 if((r & bit) == val)
339                         return 0;
340                 cpu_relax();
341         }
342         
343         /* t time yet ? */
344         while(time_before(jiffies, end))
345         {
346                 r = NCR5380_read(reg);
347                 if((r & bit) == val)
348                         return 0;
349                 if(!in_interrupt())
350                         yield();
351                 else
352                         cpu_relax();
353         }
354         return -ETIMEDOUT;
355 }
356
357 static struct {
358         unsigned char value;
359         const char *name;
360 } phases[] = {
361         {PHASE_DATAOUT, "DATAOUT"}, 
362         {PHASE_DATAIN, "DATAIN"}, 
363         {PHASE_CMDOUT, "CMDOUT"}, 
364         {PHASE_STATIN, "STATIN"}, 
365         {PHASE_MSGOUT, "MSGOUT"}, 
366         {PHASE_MSGIN, "MSGIN"}, 
367         {PHASE_UNKNOWN, "UNKNOWN"}
368 };
369
370 #if NDEBUG
371 static struct {
372         unsigned char mask;
373         const char *name;
374 } signals[] = { 
375         {SR_DBP, "PARITY"}, 
376         {SR_RST, "RST"}, 
377         {SR_BSY, "BSY"}, 
378         {SR_REQ, "REQ"}, 
379         {SR_MSG, "MSG"}, 
380         {SR_CD, "CD"}, 
381         {SR_IO, "IO"}, 
382         {SR_SEL, "SEL"}, 
383         {0, NULL}
384 }, 
385 basrs[] = {
386         {BASR_ATN, "ATN"}, 
387         {BASR_ACK, "ACK"}, 
388         {0, NULL}
389 }, 
390 icrs[] = { 
391         {ICR_ASSERT_RST, "ASSERT RST"}, 
392         {ICR_ASSERT_ACK, "ASSERT ACK"}, 
393         {ICR_ASSERT_BSY, "ASSERT BSY"}, 
394         {ICR_ASSERT_SEL, "ASSERT SEL"}, 
395         {ICR_ASSERT_ATN, "ASSERT ATN"}, 
396         {ICR_ASSERT_DATA, "ASSERT DATA"}, 
397         {0, NULL}
398 }, 
399 mrs[] = { 
400         {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, 
401         {MR_TARGET, "MODE TARGET"}, 
402         {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, 
403         {MR_ENABLE_PAR_INTR, "MODE PARITY INTR"}, 
404         {MR_MONITOR_BSY, "MODE MONITOR BSY"}, 
405         {MR_DMA_MODE, "MODE DMA"}, 
406         {MR_ARBITRATE, "MODE ARBITRATION"}, 
407         {0, NULL}
408 };
409
410 /**
411  *      NCR5380_print   -       print scsi bus signals
412  *      @instance:      adapter state to dump
413  *
414  *      Print the SCSI bus signals for debugging purposes
415  *
416  *      Locks: caller holds hostdata lock (not essential)
417  */
418
419 static void NCR5380_print(struct Scsi_Host *instance)
420 {
421         NCR5380_local_declare();
422         unsigned char status, data, basr, mr, icr, i;
423         NCR5380_setup(instance);
424
425         data = NCR5380_read(CURRENT_SCSI_DATA_REG);
426         status = NCR5380_read(STATUS_REG);
427         mr = NCR5380_read(MODE_REG);
428         icr = NCR5380_read(INITIATOR_COMMAND_REG);
429         basr = NCR5380_read(BUS_AND_STATUS_REG);
430
431         printk("STATUS_REG: %02x ", status);
432         for (i = 0; signals[i].mask; ++i)
433                 if (status & signals[i].mask)
434                         printk(",%s", signals[i].name);
435         printk("\nBASR: %02x ", basr);
436         for (i = 0; basrs[i].mask; ++i)
437                 if (basr & basrs[i].mask)
438                         printk(",%s", basrs[i].name);
439         printk("\nICR: %02x ", icr);
440         for (i = 0; icrs[i].mask; ++i)
441                 if (icr & icrs[i].mask)
442                         printk(",%s", icrs[i].name);
443         printk("\nMODE: %02x ", mr);
444         for (i = 0; mrs[i].mask; ++i)
445                 if (mr & mrs[i].mask)
446                         printk(",%s", mrs[i].name);
447         printk("\n");
448 }
449
450
451 /* 
452  *      NCR5380_print_phase     -       show SCSI phase
453  *      @instance: adapter to dump
454  *
455  *      Print the current SCSI phase for debugging purposes
456  *
457  *      Locks: none
458  */
459
460 static void NCR5380_print_phase(struct Scsi_Host *instance)
461 {
462         NCR5380_local_declare();
463         unsigned char status;
464         int i;
465         NCR5380_setup(instance);
466
467         status = NCR5380_read(STATUS_REG);
468         if (!(status & SR_REQ))
469                 printk("scsi%d : REQ not asserted, phase unknown.\n", instance->host_no);
470         else {
471                 for (i = 0; (phases[i].value != PHASE_UNKNOWN) && (phases[i].value != (status & PHASE_MASK)); ++i);
472                 printk("scsi%d : phase %s\n", instance->host_no, phases[i].name);
473         }
474 }
475 #endif
476
477 /*
478  * These need tweaking, and would probably work best as per-device 
479  * flags initialized differently for disk, tape, cd, etc devices.
480  * People with broken devices are free to experiment as to what gives
481  * the best results for them.
482  *
483  * USLEEP_SLEEP should be a minimum seek time.
484  *
485  * USLEEP_POLL should be a maximum rotational latency.
486  */
487 #ifndef USLEEP_SLEEP
488 /* 20 ms (reasonable hard disk speed) */
489 #define USLEEP_SLEEP (20*HZ/1000)
490 #endif
491 /* 300 RPM (floppy speed) */
492 #ifndef USLEEP_POLL
493 #define USLEEP_POLL (200*HZ/1000)
494 #endif
495 #ifndef USLEEP_WAITLONG
496 /* RvC: (reasonable time to wait on select error) */
497 #define USLEEP_WAITLONG USLEEP_SLEEP
498 #endif
499
500 /* 
501  * Function : int should_disconnect (unsigned char cmd)
502  *
503  * Purpose : decide whether a command would normally disconnect or 
504  *      not, since if it won't disconnect we should go to sleep.
505  *
506  * Input : cmd - opcode of SCSI command
507  *
508  * Returns : DISCONNECT_LONG if we should disconnect for a really long 
509  *      time (ie always, sleep, look for REQ active, sleep), 
510  *      DISCONNECT_TIME_TO_DATA if we would only disconnect for a normal
511  *      time-to-data delay, DISCONNECT_NONE if this command would return
512  *      immediately.
513  *
514  *      Future sleep algorithms based on time to data can exploit 
515  *      something like this so they can differentiate between "normal" 
516  *      (ie, read, write, seek) and unusual commands (ie, * format).
517  *
518  * Note : We don't deal with commands that handle an immediate disconnect,
519  *        
520  */
521
522 static int should_disconnect(unsigned char cmd)
523 {
524         switch (cmd) {
525         case READ_6:
526         case WRITE_6:
527         case SEEK_6:
528         case READ_10:
529         case WRITE_10:
530         case SEEK_10:
531                 return DISCONNECT_TIME_TO_DATA;
532         case FORMAT_UNIT:
533         case SEARCH_HIGH:
534         case SEARCH_LOW:
535         case SEARCH_EQUAL:
536                 return DISCONNECT_LONG;
537         default:
538                 return DISCONNECT_NONE;
539         }
540 }
541
542 static void NCR5380_set_timer(struct NCR5380_hostdata *hostdata, unsigned long timeout)
543 {
544         hostdata->time_expires = jiffies + timeout;
545         schedule_delayed_work(&hostdata->coroutine, timeout);
546 }
547
548
549 static int probe_irq __initdata = 0;
550
551 /**
552  *      probe_intr      -       helper for IRQ autoprobe
553  *      @irq: interrupt number
554  *      @dev_id: unused
555  *      @regs: unused
556  *
557  *      Set a flag to indicate the IRQ in question was received. This is
558  *      used by the IRQ probe code.
559  */
560  
561 static irqreturn_t __init probe_intr(int irq, void *dev_id)
562 {
563         probe_irq = irq;
564         return IRQ_HANDLED;
565 }
566
567 /**
568  *      NCR5380_probe_irq       -       find the IRQ of an NCR5380
569  *      @instance: NCR5380 controller
570  *      @possible: bitmask of ISA IRQ lines
571  *
572  *      Autoprobe for the IRQ line used by the NCR5380 by triggering an IRQ
573  *      and then looking to see what interrupt actually turned up.
574  *
575  *      Locks: none, irqs must be enabled on entry
576  */
577
578 static int __init NCR5380_probe_irq(struct Scsi_Host *instance, int possible)
579 {
580         NCR5380_local_declare();
581         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
582         unsigned long timeout;
583         int trying_irqs, i, mask;
584         NCR5380_setup(instance);
585
586         for (trying_irqs = i = 0, mask = 1; i < 16; ++i, mask <<= 1)
587                 if ((mask & possible) && (request_irq(i, &probe_intr, 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 NCR5380_print_options(struct Scsi_Host *instance)
633 {
634         printk(" generic options"
635 #ifdef AUTOPROBE_IRQ
636                " AUTOPROBE_IRQ"
637 #endif
638 #ifdef AUTOSENSE
639                " AUTOSENSE"
640 #endif
641 #ifdef DIFFERENTIAL
642                " DIFFERENTIAL"
643 #endif
644 #ifdef REAL_DMA
645                " REAL DMA"
646 #endif
647 #ifdef REAL_DMA_POLL
648                " REAL DMA POLL"
649 #endif
650 #ifdef PARITY
651                " PARITY"
652 #endif
653 #ifdef PSEUDO_DMA
654                " PSEUDO DMA"
655 #endif
656 #ifdef UNSAFE
657                " UNSAFE "
658 #endif
659             );
660         printk(" USLEEP, USLEEP_POLL=%d USLEEP_SLEEP=%d", USLEEP_POLL, USLEEP_SLEEP);
661         printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
662         if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400) {
663                 printk(" ncr53c400 release=%d", NCR53C400_PUBLIC_RELEASE);
664         }
665 }
666
667 /**
668  *      NCR5380_print_status    -       dump controller info
669  *      @instance: controller to dump
670  *
671  *      Print commands in the various queues, called from NCR5380_abort 
672  *      and NCR5380_debug to aid debugging.
673  *
674  *      Locks: called functions disable irqs
675  */
676
677 static void NCR5380_print_status(struct Scsi_Host *instance)
678 {
679         NCR5380_dprint(NDEBUG_ANY, instance);
680         NCR5380_dprint_phase(NDEBUG_ANY, instance);
681 }
682
683 /******************************************/
684 /*
685  * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
686  *
687  * *buffer: I/O buffer
688  * **start: if inout == FALSE pointer into buffer where user read should start
689  * offset: current offset
690  * length: length of buffer
691  * hostno: Scsi_Host host_no
692  * inout: TRUE - user is writing; FALSE - user is reading
693  *
694  * Return the number of bytes read from or written
695  */
696
697 #undef SPRINTF
698 #define SPRINTF(args...) do { if(pos < buffer + length-80) pos += sprintf(pos, ## args); } while(0)
699 static
700 char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length);
701 static
702 char *lprint_command(unsigned char *cmd, char *pos, char *buffer, int len);
703 static
704 char *lprint_opcode(int opcode, char *pos, char *buffer, int length);
705
706 static
707 int NCR5380_proc_info(struct Scsi_Host *instance, char *buffer, char **start, off_t offset, int length, int inout)
708 {
709         char *pos = buffer;
710         struct NCR5380_hostdata *hostdata;
711         Scsi_Cmnd *ptr;
712
713         hostdata = (struct NCR5380_hostdata *) instance->hostdata;
714
715         if (inout) {            /* Has data been written to the file ? */
716 #ifdef DTC_PUBLIC_RELEASE
717                 dtc_wmaxi = dtc_maxi = 0;
718 #endif
719 #ifdef PAS16_PUBLIC_RELEASE
720                 pas_wmaxi = pas_maxi = 0;
721 #endif
722                 return (-ENOSYS);       /* Currently this is a no-op */
723         }
724         SPRINTF("NCR5380 core release=%d.   ", NCR5380_PUBLIC_RELEASE);
725         if (((struct NCR5380_hostdata *) instance->hostdata)->flags & FLAG_NCR53C400)
726                 SPRINTF("ncr53c400 release=%d.  ", NCR53C400_PUBLIC_RELEASE);
727 #ifdef DTC_PUBLIC_RELEASE
728         SPRINTF("DTC 3180/3280 release %d", DTC_PUBLIC_RELEASE);
729 #endif
730 #ifdef T128_PUBLIC_RELEASE
731         SPRINTF("T128 release %d", T128_PUBLIC_RELEASE);
732 #endif
733 #ifdef GENERIC_NCR5380_PUBLIC_RELEASE
734         SPRINTF("Generic5380 release %d", GENERIC_NCR5380_PUBLIC_RELEASE);
735 #endif
736 #ifdef PAS16_PUBLIC_RELEASE
737         SPRINTF("PAS16 release=%d", PAS16_PUBLIC_RELEASE);
738 #endif
739
740         SPRINTF("\nBase Addr: 0x%05lX    ", (long) instance->base);
741         SPRINTF("io_port: %04x      ", (int) instance->io_port);
742         if (instance->irq == SCSI_IRQ_NONE)
743                 SPRINTF("IRQ: None.\n");
744         else
745                 SPRINTF("IRQ: %d.\n", instance->irq);
746
747 #ifdef DTC_PUBLIC_RELEASE
748         SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", dtc_wmaxi, dtc_maxi);
749 #endif
750 #ifdef PAS16_PUBLIC_RELEASE
751         SPRINTF("Highwater I/O busy_spin_counts -- write: %d  read: %d\n", pas_wmaxi, pas_maxi);
752 #endif
753         spin_lock_irq(instance->host_lock);
754         if (!hostdata->connected)
755                 SPRINTF("scsi%d: no currently connected command\n", instance->host_no);
756         else
757                 pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected, pos, buffer, length);
758         SPRINTF("scsi%d: issue_queue\n", instance->host_no);
759         for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
760                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
761
762         SPRINTF("scsi%d: disconnected_queue\n", instance->host_no);
763         for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; ptr = (Scsi_Cmnd *) ptr->host_scribble)
764                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
765         spin_unlock_irq(instance->host_lock);
766         
767         *start = buffer;
768         if (pos - buffer < offset)
769                 return 0;
770         else if (pos - buffer - offset < length)
771                 return pos - buffer - offset;
772         return length;
773 }
774
775 static char *lprint_Scsi_Cmnd(Scsi_Cmnd * cmd, char *pos, char *buffer, int length)
776 {
777         SPRINTF("scsi%d : destination target %d, lun %d\n", cmd->device->host->host_no, cmd->device->id, cmd->device->lun);
778         SPRINTF("        command = ");
779         pos = lprint_command(cmd->cmnd, pos, buffer, length);
780         return (pos);
781 }
782
783 static char *lprint_command(unsigned char *command, char *pos, char *buffer, int length)
784 {
785         int i, s;
786         pos = lprint_opcode(command[0], pos, buffer, length);
787         for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
788                 SPRINTF("%02x ", command[i]);
789         SPRINTF("\n");
790         return (pos);
791 }
792
793 static char *lprint_opcode(int opcode, char *pos, char *buffer, int length)
794 {
795         SPRINTF("%2d (0x%02x)", opcode, opcode);
796         return (pos);
797 }
798
799
800 /**
801  *      NCR5380_init    -       initialise an NCR5380
802  *      @instance: adapter to configure
803  *      @flags: control flags
804  *
805  *      Initializes *instance and corresponding 5380 chip,
806  *      with flags OR'd into the initial flags value.
807  *
808  *      Notes : I assume that the host, hostno, and id bits have been
809  *      set correctly.  I don't care about the irq and other fields. 
810  *
811  *      Returns 0 for success
812  *
813  *      Locks: interrupts must be enabled when we are called 
814  */
815
816 static int __devinit NCR5380_init(struct Scsi_Host *instance, int flags)
817 {
818         NCR5380_local_declare();
819         int i, pass;
820         unsigned long timeout;
821         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
822
823         if(in_interrupt())
824                 printk(KERN_ERR "NCR5380_init called with interrupts off!\n");
825         /* 
826          * On NCR53C400 boards, NCR5380 registers are mapped 8 past 
827          * the base address.
828          */
829
830 #ifdef NCR53C400
831         if (flags & FLAG_NCR53C400)
832                 instance->NCR5380_instance_name += NCR53C400_address_adjust;
833 #endif
834
835         NCR5380_setup(instance);
836
837         hostdata->aborted = 0;
838         hostdata->id_mask = 1 << instance->this_id;
839         for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
840                 if (i > hostdata->id_mask)
841                         hostdata->id_higher_mask |= i;
842         for (i = 0; i < 8; ++i)
843                 hostdata->busy[i] = 0;
844 #ifdef REAL_DMA
845         hostdata->dmalen = 0;
846 #endif
847         hostdata->targets_present = 0;
848         hostdata->connected = NULL;
849         hostdata->issue_queue = NULL;
850         hostdata->disconnected_queue = NULL;
851         
852         INIT_DELAYED_WORK(&hostdata->coroutine, NCR5380_main);
853         
854 #ifdef NCR5380_STATS
855         for (i = 0; i < 8; ++i) {
856                 hostdata->time_read[i] = 0;
857                 hostdata->time_write[i] = 0;
858                 hostdata->bytes_read[i] = 0;
859                 hostdata->bytes_write[i] = 0;
860         }
861         hostdata->timebase = 0;
862         hostdata->pendingw = 0;
863         hostdata->pendingr = 0;
864 #endif
865
866         /* The CHECK code seems to break the 53C400. Will check it later maybe */
867         if (flags & FLAG_NCR53C400)
868                 hostdata->flags = FLAG_HAS_LAST_BYTE_SENT | flags;
869         else
870                 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT | flags;
871
872         hostdata->host = instance;
873         hostdata->time_expires = 0;
874
875 #ifndef AUTOSENSE
876         if ((instance->cmd_per_lun > 1) || instance->can_queue > 1)
877                     printk(KERN_WARNING "scsi%d : WARNING : support for multiple outstanding commands enabled\n" "         without AUTOSENSE option, contingent allegiance conditions may\n"
878                            "         be incorrectly cleared.\n", instance->host_no);
879 #endif                          /* def AUTOSENSE */
880
881         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
882         NCR5380_write(MODE_REG, MR_BASE);
883         NCR5380_write(TARGET_COMMAND_REG, 0);
884         NCR5380_write(SELECT_ENABLE_REG, 0);
885
886 #ifdef NCR53C400
887         if (hostdata->flags & FLAG_NCR53C400) {
888                 NCR5380_write(C400_CONTROL_STATUS_REG, CSR_BASE);
889         }
890 #endif
891
892         /* 
893          * Detect and correct bus wedge problems.
894          *
895          * If the system crashed, it may have crashed in a state 
896          * where a SCSI command was still executing, and the 
897          * SCSI bus is not in a BUS FREE STATE.
898          *
899          * If this is the case, we'll try to abort the currently
900          * established nexus which we know nothing about, and that
901          * failing, do a hard reset of the SCSI bus 
902          */
903
904         for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
905                 switch (pass) {
906                 case 1:
907                 case 3:
908                 case 5:
909                         printk(KERN_INFO "scsi%d: SCSI bus busy, waiting up to five seconds\n", instance->host_no);
910                         timeout = jiffies + 5 * HZ;
911                         NCR5380_poll_politely(instance, STATUS_REG, SR_BSY, 0, 5*HZ);
912                         break;
913                 case 2:
914                         printk(KERN_WARNING "scsi%d: bus busy, attempting abort\n", instance->host_no);
915                         do_abort(instance);
916                         break;
917                 case 4:
918                         printk(KERN_WARNING "scsi%d: bus busy, attempting reset\n", instance->host_no);
919                         do_reset(instance);
920                         break;
921                 case 6:
922                         printk(KERN_ERR "scsi%d: bus locked solid or invalid override\n", instance->host_no);
923                         return -ENXIO;
924                 }
925         }
926         return 0;
927 }
928
929 /**
930  *      NCR5380_exit    -       remove an NCR5380
931  *      @instance: adapter to remove
932  */
933
934 static void __devexit NCR5380_exit(struct Scsi_Host *instance)
935 {
936         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
937
938         cancel_delayed_work(&hostdata->coroutine);
939         flush_scheduled_work();
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(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] += cmd->request_bufflen;
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] += cmd->request_bufflen;
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
1024 /**
1025  *      NCR5380_main    -       NCR state machines
1026  *
1027  *      NCR5380_main is a coroutine that runs as long as more work can 
1028  *      be done on the NCR5380 host adapters in a system.  Both 
1029  *      NCR5380_queue_command() and NCR5380_intr() will try to start it 
1030  *      in case it is not running.
1031  * 
1032  *      Locks: called as its own thread with no locks held. Takes the
1033  *      host lock and called routines may take the isa dma lock.
1034  */
1035
1036 static void NCR5380_main(struct work_struct *work)
1037 {
1038         struct NCR5380_hostdata *hostdata =
1039                 container_of(work, struct NCR5380_hostdata, coroutine.work);
1040         struct Scsi_Host *instance = hostdata->host;
1041         Scsi_Cmnd *tmp, *prev;
1042         int done;
1043         
1044         spin_lock_irq(instance->host_lock);
1045         do {
1046                 /* Lock held here */
1047                 done = 1;
1048                 if (!hostdata->connected && !hostdata->selecting) {
1049                         dprintk(NDEBUG_MAIN, ("scsi%d : not connected\n", instance->host_no));
1050                         /*
1051                          * Search through the issue_queue for a command destined
1052                          * for a target that's not busy.
1053                          */
1054                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble) 
1055                         {
1056                                 if (prev != tmp)
1057                                         dprintk(NDEBUG_LISTS, ("MAIN tmp=%p   target=%d   busy=%d lun=%d\n", tmp, tmp->target, hostdata->busy[tmp->target], tmp->lun));
1058                                 /*  When we find one, remove it from the issue queue. */
1059                                 if (!(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))) {
1060                                         if (prev) {
1061                                                 REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
1062                                                 prev->host_scribble = tmp->host_scribble;
1063                                         } else {
1064                                                 REMOVE(-1, hostdata->issue_queue, tmp, tmp->host_scribble);
1065                                                 hostdata->issue_queue = (Scsi_Cmnd *) tmp->host_scribble;
1066                                         }
1067                                         tmp->host_scribble = NULL;
1068
1069                                         /* 
1070                                          * Attempt to establish an I_T_L nexus here. 
1071                                          * On success, instance->hostdata->connected is set.
1072                                          * On failure, we must add the command back to the
1073                                          *   issue queue so we can keep trying. 
1074                                          */
1075                                         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));
1076         
1077                                         /*
1078                                          * A successful selection is defined as one that 
1079                                          * leaves us with the command connected and 
1080                                          * in hostdata->connected, OR has terminated the
1081                                          * command.
1082                                          *
1083                                          * With successful commands, we fall through
1084                                          * and see if we can do an information transfer,
1085                                          * with failures we will restart.
1086                                          */
1087                                         hostdata->selecting = NULL;
1088                                         /* RvC: have to preset this to indicate a new command is being performed */
1089
1090                                         if (!NCR5380_select(instance, tmp,
1091                                                             /* 
1092                                                              * REQUEST SENSE commands are issued without tagged
1093                                                              * queueing, even on SCSI-II devices because the 
1094                                                              * contingent allegiance condition exists for the 
1095                                                              * entire unit.
1096                                                              */
1097                                                             (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1098                                                 break;
1099                                         } else {
1100                                                 LIST(tmp, hostdata->issue_queue);
1101                                                 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1102                                                 hostdata->issue_queue = tmp;
1103                                                 done = 0;
1104                                                 dprintk(NDEBUG_MAIN|NDEBUG_QUEUES, ("scsi%d : main(): select() failed, returned to issue_queue\n", instance->host_no));
1105                                         }
1106                                         /* lock held here still */
1107                                 }       /* if target/lun is not busy */
1108                         }       /* for */
1109                         /* exited locked */
1110                 }       /* if (!hostdata->connected) */
1111                 if (hostdata->selecting) {
1112                         tmp = (Scsi_Cmnd *) hostdata->selecting;
1113                         /* Selection will drop and retake the lock */
1114                         if (!NCR5380_select(instance, tmp, (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : TAG_NEXT)) {
1115                                 /* Ok ?? */
1116                         } else {
1117                                 /* RvC: device failed, so we wait a long time
1118                                    this is needed for Mustek scanners, that
1119                                    do not respond to commands immediately
1120                                    after a scan */
1121                                 printk(KERN_DEBUG "scsi%d: device %d did not respond in time\n", instance->host_no, tmp->device->id);
1122                                 LIST(tmp, hostdata->issue_queue);
1123                                 tmp->host_scribble = (unsigned char *) hostdata->issue_queue;
1124                                 hostdata->issue_queue = tmp;
1125                                 NCR5380_set_timer(hostdata, USLEEP_WAITLONG);
1126                         }
1127                 }       /* if hostdata->selecting */
1128                 if (hostdata->connected
1129 #ifdef REAL_DMA
1130                     && !hostdata->dmalen
1131 #endif
1132                     && (!hostdata->time_expires || time_before_eq(hostdata->time_expires, jiffies))
1133                     ) {
1134                         dprintk(NDEBUG_MAIN, ("scsi%d : main() : performing information transfer\n", instance->host_no));
1135                         NCR5380_information_transfer(instance);
1136                         dprintk(NDEBUG_MAIN, ("scsi%d : main() : done set false\n", instance->host_no));
1137                         done = 0;
1138                 } else
1139                         break;
1140         } while (!done);
1141         
1142         spin_unlock_irq(instance->host_lock);
1143 }
1144
1145 #ifndef DONT_USE_INTR
1146
1147 /**
1148  *      NCR5380_intr    -       generic NCR5380 irq handler
1149  *      @irq: interrupt number
1150  *      @dev_id: device info
1151  *
1152  *      Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1153  *      from the disconnected queue, and restarting NCR5380_main() 
1154  *      as required.
1155  *
1156  *      Locks: takes the needed instance locks
1157  */
1158
1159 static irqreturn_t NCR5380_intr(int irq, void *dev_id) 
1160 {
1161         NCR5380_local_declare();
1162         struct Scsi_Host *instance = (struct Scsi_Host *)dev_id;
1163         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1164         int done;
1165         unsigned char basr;
1166         unsigned long flags;
1167
1168         dprintk(NDEBUG_INTR, ("scsi : NCR5380 irq %d triggered\n", irq));
1169
1170         do {
1171                 done = 1;
1172                 spin_lock_irqsave(instance->host_lock, flags);
1173                 /* Look for pending interrupts */
1174                 NCR5380_setup(instance);
1175                 basr = NCR5380_read(BUS_AND_STATUS_REG);
1176                 /* XXX dispatch to appropriate routine if found and done=0 */
1177                 if (basr & BASR_IRQ) {
1178                         NCR5380_dprint(NDEBUG_INTR, instance);
1179                         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1180                                 done = 0;
1181                                 dprintk(NDEBUG_INTR, ("scsi%d : SEL interrupt\n", instance->host_no));
1182                                 NCR5380_reselect(instance);
1183                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1184                         } else if (basr & BASR_PARITY_ERROR) {
1185                                 dprintk(NDEBUG_INTR, ("scsi%d : PARITY interrupt\n", instance->host_no));
1186                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1187                         } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1188                                 dprintk(NDEBUG_INTR, ("scsi%d : RESET interrupt\n", instance->host_no));
1189                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1190                         } else {
1191 #if defined(REAL_DMA)
1192                                 /*
1193                                  * We should only get PHASE MISMATCH and EOP interrupts
1194                                  * if we have DMA enabled, so do a sanity check based on
1195                                  * the current setting of the MODE register.
1196                                  */
1197
1198                                 if ((NCR5380_read(MODE_REG) & MR_DMA) && ((basr & BASR_END_DMA_TRANSFER) || !(basr & BASR_PHASE_MATCH))) {
1199                                         int transfered;
1200
1201                                         if (!hostdata->connected)
1202                                                 panic("scsi%d : received end of DMA interrupt with no connected cmd\n", instance->hostno);
1203
1204                                         transfered = (hostdata->dmalen - NCR5380_dma_residual(instance));
1205                                         hostdata->connected->SCp.this_residual -= transferred;
1206                                         hostdata->connected->SCp.ptr += transferred;
1207                                         hostdata->dmalen = 0;
1208
1209                                         (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1210                                                         
1211                                         /* FIXME: we need to poll briefly then defer a workqueue task ! */
1212                                         NCR5380_poll_politely(hostdata, BUS_AND_STATUS_REG, BASR_ACK, 0, 2*HZ);
1213
1214                                         NCR5380_write(MODE_REG, MR_BASE);
1215                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1216                                 }
1217 #else
1218                                 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)));
1219                                 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1220 #endif
1221                         }
1222                 }       /* if BASR_IRQ */
1223                 spin_unlock_irqrestore(instance->host_lock, flags);
1224                 if(!done)
1225                         schedule_delayed_work(&hostdata->coroutine, 0);
1226         } while (!done);
1227         return IRQ_HANDLED;
1228 }
1229
1230 #endif 
1231
1232 /**
1233  *      collect_stats           -       collect stats on a scsi command
1234  *      @hostdata: adapter 
1235  *      @cmd: command being issued
1236  *
1237  *      Update the statistical data by parsing the command in question
1238  */
1239  
1240 static void collect_stats(struct NCR5380_hostdata *hostdata, Scsi_Cmnd * cmd) 
1241 {
1242 #ifdef NCR5380_STATS
1243         switch (cmd->cmnd[0]) {
1244         case WRITE:
1245         case WRITE_6:
1246         case WRITE_10:
1247                 hostdata->time_write[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1248                 hostdata->pendingw--;
1249                 break;
1250         case READ:
1251         case READ_6:
1252         case READ_10:
1253                 hostdata->time_read[scmd_id(cmd)] += (jiffies - hostdata->timebase);
1254                 hostdata->pendingr--;
1255                 break;
1256         }
1257 #endif
1258 }
1259
1260
1261 /* 
1262  * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, 
1263  *      int tag);
1264  *
1265  * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1266  *      including ARBITRATION, SELECTION, and initial message out for 
1267  *      IDENTIFY and queue messages. 
1268  *
1269  * Inputs : instance - instantiation of the 5380 driver on which this 
1270  *      target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for 
1271  *      new tag, TAG_NONE for untagged queueing, otherwise set to the tag for 
1272  *      the command that is presently connected.
1273  * 
1274  * Returns : -1 if selection could not execute for some reason,
1275  *      0 if selection succeeded or failed because the target 
1276  *      did not respond.
1277  *
1278  * Side effects : 
1279  *      If bus busy, arbitration failed, etc, NCR5380_select() will exit 
1280  *              with registers as they should have been on entry - ie
1281  *              SELECT_ENABLE will be set appropriately, the NCR5380
1282  *              will cease to drive any SCSI bus signals.
1283  *
1284  *      If successful : I_T_L or I_T_L_Q nexus will be established, 
1285  *              instance->connected will be set to cmd.  
1286  *              SELECT interrupt will be disabled.
1287  *
1288  *      If failed (no target) : cmd->scsi_done() will be called, and the 
1289  *              cmd->result host byte set to DID_BAD_TARGET.
1290  *
1291  *      Locks: caller holds hostdata lock in IRQ mode
1292  */
1293  
1294 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd * cmd, int tag) 
1295 {
1296         NCR5380_local_declare();
1297         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
1298         unsigned char tmp[3], phase;
1299         unsigned char *data;
1300         int len;
1301         unsigned long timeout;
1302         unsigned char value;
1303         int err;
1304         NCR5380_setup(instance);
1305
1306         if (hostdata->selecting)
1307                 goto part2;
1308
1309         hostdata->restart_select = 0;
1310
1311         NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1312         dprintk(NDEBUG_ARBITRATION, ("scsi%d : starting arbitration, id = %d\n", instance->host_no, instance->this_id));
1313
1314         /* 
1315          * Set the phase bits to 0, otherwise the NCR5380 won't drive the 
1316          * data bus during SELECTION.
1317          */
1318
1319         NCR5380_write(TARGET_COMMAND_REG, 0);
1320
1321         /* 
1322          * Start arbitration.
1323          */
1324
1325         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1326         NCR5380_write(MODE_REG, MR_ARBITRATE);
1327
1328
1329         /* We can be relaxed here, interrupts are on, we are
1330            in workqueue context, the birds are singing in the trees */
1331         spin_unlock_irq(instance->host_lock);
1332         err = NCR5380_poll_politely(instance, INITIATOR_COMMAND_REG, ICR_ARBITRATION_PROGRESS, ICR_ARBITRATION_PROGRESS, 5*HZ);
1333         spin_lock_irq(instance->host_lock);
1334         if (err < 0) {
1335                 printk(KERN_DEBUG "scsi: arbitration timeout at %d\n", __LINE__);
1336                 NCR5380_write(MODE_REG, MR_BASE);
1337                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1338                 goto failed;
1339         }
1340
1341         dprintk(NDEBUG_ARBITRATION, ("scsi%d : arbitration complete\n", instance->host_no));
1342
1343         /* 
1344          * The arbitration delay is 2.2us, but this is a minimum and there is 
1345          * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1346          * the integral nature of udelay().
1347          *
1348          */
1349
1350         udelay(3);
1351
1352         /* Check for lost arbitration */
1353         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)) {
1354                 NCR5380_write(MODE_REG, MR_BASE);
1355                 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting MR_ARBITRATE\n", instance->host_no));
1356                 goto failed;
1357         }
1358         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL);
1359
1360         if (!(hostdata->flags & FLAG_DTC3181E) &&
1361             /* RvC: DTC3181E has some trouble with this
1362              *      so we simply removed it. Seems to work with
1363              *      only Mustek scanner attached
1364              */
1365             (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST)) {
1366                 NCR5380_write(MODE_REG, MR_BASE);
1367                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1368                 dprintk(NDEBUG_ARBITRATION, ("scsi%d : lost arbitration, deasserting ICR_ASSERT_SEL\n", instance->host_no));
1369                 goto failed;
1370         }
1371         /* 
1372          * Again, bus clear + bus settle time is 1.2us, however, this is 
1373          * a minimum so we'll udelay ceil(1.2)
1374          */
1375
1376         udelay(2);
1377
1378         dprintk(NDEBUG_ARBITRATION, ("scsi%d : won arbitration\n", instance->host_no));
1379
1380         /* 
1381          * Now that we have won arbitration, start Selection process, asserting 
1382          * the host and target ID's on the SCSI bus.
1383          */
1384
1385         NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << scmd_id(cmd))));
1386
1387         /* 
1388          * Raise ATN while SEL is true before BSY goes false from arbitration,
1389          * since this is the only way to guarantee that we'll get a MESSAGE OUT
1390          * phase immediately after selection.
1391          */
1392
1393         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1394         NCR5380_write(MODE_REG, MR_BASE);
1395
1396         /* 
1397          * Reselect interrupts must be turned off prior to the dropping of BSY,
1398          * otherwise we will trigger an interrupt.
1399          */
1400         NCR5380_write(SELECT_ENABLE_REG, 0);
1401
1402         /*
1403          * The initiator shall then wait at least two deskew delays and release 
1404          * the BSY signal.
1405          */
1406         udelay(1);              /* wingel -- wait two bus deskew delay >2*45ns */
1407
1408         /* Reset BSY */
1409         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1410
1411         /* 
1412          * Something weird happens when we cease to drive BSY - looks
1413          * like the board/chip is letting us do another read before the 
1414          * appropriate propagation delay has expired, and we're confusing
1415          * a BSY signal from ourselves as the target's response to SELECTION.
1416          *
1417          * A small delay (the 'C++' frontend breaks the pipeline with an
1418          * unnecessary jump, making it work on my 386-33/Trantor T128, the
1419          * tighter 'C' code breaks and requires this) solves the problem - 
1420          * the 1 us delay is arbitrary, and only used because this delay will 
1421          * be the same on other platforms and since it works here, it should 
1422          * work there.
1423          *
1424          * wingel suggests that this could be due to failing to wait
1425          * one deskew delay.
1426          */
1427
1428         udelay(1);
1429
1430         dprintk(NDEBUG_SELECTION, ("scsi%d : selecting target %d\n", instance->host_no, scmd_id(cmd)));
1431
1432         /* 
1433          * The SCSI specification calls for a 250 ms timeout for the actual 
1434          * selection.
1435          */
1436
1437         timeout = jiffies + (250 * HZ / 1000);
1438
1439         /* 
1440          * XXX very interesting - we're seeing a bounce where the BSY we 
1441          * asserted is being reflected / still asserted (propagation delay?)
1442          * and it's detecting as true.  Sigh.
1443          */
1444
1445         hostdata->select_time = 0;      /* we count the clock ticks at which we polled */
1446         hostdata->selecting = cmd;
1447
1448 part2:
1449         /* RvC: here we enter after a sleeping period, or immediately after
1450            execution of part 1
1451            we poll only once ech clock tick */
1452         value = NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO);
1453
1454         if (!value && (hostdata->select_time < HZ/4)) {
1455                 /* RvC: we still must wait for a device response */
1456                 hostdata->select_time++;        /* after 25 ticks the device has failed */
1457                 NCR5380_set_timer(hostdata, 1);
1458                 return 0;       /* RvC: we return here with hostdata->selecting set,
1459                                    to go to sleep */
1460         }
1461
1462         hostdata->selecting = NULL;/* clear this pointer, because we passed the
1463                                            waiting period */
1464         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1465                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1466                 NCR5380_reselect(instance);
1467                 printk("scsi%d : reselection after won arbitration?\n", instance->host_no);
1468                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1469                 return -1;
1470         }
1471         /* 
1472          * No less than two deskew delays after the initiator detects the 
1473          * BSY signal is true, it shall release the SEL signal and may 
1474          * change the DATA BUS.                                     -wingel
1475          */
1476
1477         udelay(1);
1478
1479         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1480
1481         if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1482                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1483                 if (hostdata->targets_present & (1 << scmd_id(cmd))) {
1484                         printk(KERN_DEBUG "scsi%d : weirdness\n", instance->host_no);
1485                         if (hostdata->restart_select)
1486                                 printk(KERN_DEBUG "\trestart select\n");
1487                         NCR5380_dprint(NDEBUG_SELECTION, instance);
1488                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1489                         return -1;
1490                 }
1491                 cmd->result = DID_BAD_TARGET << 16;
1492                 collect_stats(hostdata, cmd);
1493                 cmd->scsi_done(cmd);
1494                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1495                 dprintk(NDEBUG_SELECTION, ("scsi%d : target did not respond within 250ms\n", instance->host_no));
1496                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1497                 return 0;
1498         }
1499         hostdata->targets_present |= (1 << scmd_id(cmd));
1500
1501         /*
1502          * Since we followed the SCSI spec, and raised ATN while SEL 
1503          * was true but before BSY was false during selection, the information
1504          * transfer phase should be a MESSAGE OUT phase so that we can send the
1505          * IDENTIFY message.
1506          * 
1507          * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1508          * message (2 bytes) with a tag ID that we increment with every command
1509          * until it wraps back to 0.
1510          *
1511          * XXX - it turns out that there are some broken SCSI-II devices,
1512          *       which claim to support tagged queuing but fail when more than
1513          *       some number of commands are issued at once.
1514          */
1515
1516         /* Wait for start of REQ/ACK handshake */
1517
1518         spin_unlock_irq(instance->host_lock);
1519         err = NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, HZ);
1520         spin_lock_irq(instance->host_lock);
1521         
1522         if(err) {
1523                 printk(KERN_ERR "scsi%d: timeout at NCR5380.c:%d\n", instance->host_no, __LINE__);
1524                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1525                 goto failed;
1526         }
1527
1528         dprintk(NDEBUG_SELECTION, ("scsi%d : target %d selected, going into MESSAGE OUT phase.\n", instance->host_no, cmd->device->id));
1529         tmp[0] = IDENTIFY(((instance->irq == SCSI_IRQ_NONE) ? 0 : 1), cmd->device->lun);
1530
1531         len = 1;
1532         cmd->tag = 0;
1533
1534         /* Send message(s) */
1535         data = tmp;
1536         phase = PHASE_MSGOUT;
1537         NCR5380_transfer_pio(instance, &phase, &len, &data);
1538         dprintk(NDEBUG_SELECTION, ("scsi%d : nexus established.\n", instance->host_no));
1539         /* XXX need to handle errors here */
1540         hostdata->connected = cmd;
1541         hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1542
1543         if (cmd->SCp.ptr != (char *)cmd->sense_buffer) {
1544                 initialize_SCp(cmd);
1545         }
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 transfered 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 transfered 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 | MR_ENABLE_PAR_CHECK | MR_ENABLE_PAR_INTR | MR_ENABLE_EOP_INTR | MR_DMA_MODE | MR_MONITOR_BSY);
1861         else
1862                 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE);
1863 #endif                          /* def REAL_DMA */
1864
1865         dprintk(NDEBUG_DMA, ("scsi%d : mode reg = 0x%X\n", instance->host_no, NCR5380_read(MODE_REG)));
1866
1867         /* 
1868          *      On the PAS16 at least I/O recovery delays are not needed here.
1869          *      Everyone else seems to want them.
1870          */
1871
1872         if (p & SR_IO) {
1873                 io_recovery_delay(1);
1874                 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1875         } else {
1876                 io_recovery_delay(1);
1877                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1878                 io_recovery_delay(1);
1879                 NCR5380_write(START_DMA_SEND_REG, 0);
1880                 io_recovery_delay(1);
1881         }
1882
1883 #if defined(REAL_DMA_POLL)
1884         do {
1885                 tmp = NCR5380_read(BUS_AND_STATUS_REG);
1886         } while ((tmp & BASR_PHASE_MATCH) && !(tmp & (BASR_BUSY_ERROR | BASR_END_DMA_TRANSFER)));
1887
1888 /*
1889    At this point, either we've completed DMA, or we have a phase mismatch,
1890    or we've unexpectedly lost BUSY (which is a real error).
1891
1892    For write DMAs, we want to wait until the last byte has been
1893    transferred out over the bus before we turn off DMA mode.  Alas, there
1894    seems to be no terribly good way of doing this on a 5380 under all
1895    conditions.  For non-scatter-gather operations, we can wait until REQ
1896    and ACK both go false, or until a phase mismatch occurs.  Gather-writes
1897    are nastier, since the device will be expecting more data than we
1898    are prepared to send it, and REQ will remain asserted.  On a 53C8[01] we
1899    could test LAST BIT SENT to assure transfer (I imagine this is precisely
1900    why this signal was added to the newer chips) but on the older 538[01]
1901    this signal does not exist.  The workaround for this lack is a watchdog;
1902    we bail out of the wait-loop after a modest amount of wait-time if
1903    the usual exit conditions are not met.  Not a terribly clean or
1904    correct solution :-%
1905
1906    Reads are equally tricky due to a nasty characteristic of the NCR5380.
1907    If the chip is in DMA mode for an READ, it will respond to a target's
1908    REQ by latching the SCSI data into the INPUT DATA register and asserting
1909    ACK, even if it has _already_ been notified by the DMA controller that
1910    the current DMA transfer has completed!  If the NCR5380 is then taken
1911    out of DMA mode, this already-acknowledged byte is lost.
1912
1913    This is not a problem for "one DMA transfer per command" reads, because
1914    the situation will never arise... either all of the data is DMA'ed
1915    properly, or the target switches to MESSAGE IN phase to signal a
1916    disconnection (either operation bringing the DMA to a clean halt).
1917    However, in order to handle scatter-reads, we must work around the
1918    problem.  The chosen fix is to DMA N-2 bytes, then check for the
1919    condition before taking the NCR5380 out of DMA mode.  One or two extra
1920    bytes are transferred via PIO as necessary to fill out the original
1921    request.
1922  */
1923
1924         if (p & SR_IO) {
1925 #ifdef READ_OVERRUNS
1926                 udelay(10);
1927                 if (((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) == (BASR_PHASE_MATCH | BASR_ACK))) {
1928                         saved_data = NCR5380_read(INPUT_DATA_REGISTER);
1929                         overrun = 1;
1930                 }
1931 #endif
1932         } else {
1933                 int limit = 100;
1934                 while (((tmp = NCR5380_read(BUS_AND_STATUS_REG)) & BASR_ACK) || (NCR5380_read(STATUS_REG) & SR_REQ)) {
1935                         if (!(tmp & BASR_PHASE_MATCH))
1936                                 break;
1937                         if (--limit < 0)
1938                                 break;
1939                 }
1940         }
1941
1942         dprintk(NDEBUG_DMA, ("scsi%d : polled DMA transfer complete, basr 0x%X, sr 0x%X\n", instance->host_no, tmp, NCR5380_read(STATUS_REG)));
1943
1944         NCR5380_write(MODE_REG, MR_BASE);
1945         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1946
1947         residue = NCR5380_dma_residual(instance);
1948         c -= residue;
1949         *count -= c;
1950         *data += c;
1951         *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
1952
1953 #ifdef READ_OVERRUNS
1954         if (*phase == p && (p & SR_IO) && residue == 0) {
1955                 if (overrun) {
1956                         dprintk(NDEBUG_DMA, ("Got an input overrun, using saved byte\n"));
1957                         **data = saved_data;
1958                         *data += 1;
1959                         *count -= 1;
1960                         cnt = toPIO = 1;
1961                 } else {
1962                         printk("No overrun??\n");
1963                         cnt = toPIO = 2;
1964                 }
1965                 dprintk(NDEBUG_DMA, ("Doing %d-byte PIO to 0x%X\n", cnt, *data));
1966                 NCR5380_transfer_pio(instance, phase, &cnt, data);
1967                 *count -= toPIO - cnt;
1968         }
1969 #endif
1970
1971         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)));
1972         return 0;
1973
1974 #elif defined(REAL_DMA)
1975         return 0;
1976 #else                           /* defined(REAL_DMA_POLL) */
1977         if (p & SR_IO) {
1978 #ifdef DMA_WORKS_RIGHT
1979                 foo = NCR5380_pread(instance, d, c);
1980 #else
1981                 int diff = 1;
1982                 if (hostdata->flags & FLAG_NCR53C400) {
1983                         diff = 0;
1984                 }
1985                 if (!(foo = NCR5380_pread(instance, d, c - diff))) {
1986                         /*
1987                          * We can't disable DMA mode after successfully transferring 
1988                          * what we plan to be the last byte, since that would open up
1989                          * a race condition where if the target asserted REQ before 
1990                          * we got the DMA mode reset, the NCR5380 would have latched
1991                          * an additional byte into the INPUT DATA register and we'd
1992                          * have dropped it.
1993                          * 
1994                          * The workaround was to transfer one fewer bytes than we 
1995                          * intended to with the pseudo-DMA read function, wait for 
1996                          * the chip to latch the last byte, read it, and then disable
1997                          * pseudo-DMA mode.
1998                          * 
1999                          * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
2000                          * REQ is deasserted when ACK is asserted, and not reasserted
2001                          * until ACK goes false.  Since the NCR5380 won't lower ACK
2002                          * until DACK is asserted, which won't happen unless we twiddle
2003                          * the DMA port or we take the NCR5380 out of DMA mode, we 
2004                          * can guarantee that we won't handshake another extra 
2005                          * byte.
2006                          */
2007
2008                         if (!(hostdata->flags & FLAG_NCR53C400)) {
2009                                 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ));
2010                                 /* Wait for clean handshake */
2011                                 while (NCR5380_read(STATUS_REG) & SR_REQ);
2012                                 d[c - 1] = NCR5380_read(INPUT_DATA_REG);
2013                         }
2014                 }
2015 #endif
2016         } else {
2017 #ifdef DMA_WORKS_RIGHT
2018                 foo = NCR5380_pwrite(instance, d, c);
2019 #else
2020                 int timeout;
2021                 dprintk(NDEBUG_C400_PWRITE, ("About to pwrite %d bytes\n", c));
2022                 if (!(foo = NCR5380_pwrite(instance, d, c))) {
2023                         /*
2024                          * Wait for the last byte to be sent.  If REQ is being asserted for 
2025                          * the byte we're interested, we'll ACK it and it will go false.  
2026                          */
2027                         if (!(hostdata->flags & FLAG_HAS_LAST_BYTE_SENT)) {
2028                                 timeout = 20000;
2029                                 while (!(NCR5380_read(BUS_AND_STATUS_REG) & BASR_DRQ) && (NCR5380_read(BUS_AND_STATUS_REG) & BASR_PHASE_MATCH));
2030
2031                                 if (!timeout)
2032                                         dprintk(NDEBUG_LAST_BYTE_SENT, ("scsi%d : timed out on last byte\n", instance->host_no));
2033
2034                                 if (hostdata->flags & FLAG_CHECK_LAST_BYTE_SENT) {
2035                                         hostdata->flags &= ~FLAG_CHECK_LAST_BYTE_SENT;
2036                                         if (NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT) {
2037                                                 hostdata->flags |= FLAG_HAS_LAST_BYTE_SENT;
2038                                                 dprintk(NDEBUG_LAST_WRITE_SENT, ("scsi%d : last bit sent works\n", instance->host_no));
2039                                         }
2040                                 }
2041                         } else {
2042                                 dprintk(NDEBUG_C400_PWRITE, ("Waiting for LASTBYTE\n"));
2043                                 while (!(NCR5380_read(TARGET_COMMAND_REG) & TCR_LAST_BYTE_SENT));
2044                                 dprintk(NDEBUG_C400_PWRITE, ("Got LASTBYTE\n"));
2045                         }
2046                 }
2047 #endif
2048         }
2049         NCR5380_write(MODE_REG, MR_BASE);
2050         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2051
2052         if ((!(p & SR_IO)) && (hostdata->flags & FLAG_NCR53C400)) {
2053                 dprintk(NDEBUG_C400_PWRITE, ("53C400w: Checking for IRQ\n"));
2054                 if (NCR5380_read(BUS_AND_STATUS_REG) & BASR_IRQ) {
2055                         dprintk(NDEBUG_C400_PWRITE, ("53C400w:    got it, reading reset interrupt reg\n"));
2056                         NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2057                 } else {
2058                         printk("53C400w:    IRQ NOT THERE!\n");
2059                 }
2060         }
2061         *data = d + c;
2062         *count = 0;
2063         *phase = NCR5380_read(STATUS_REG) & PHASE_MASK;
2064 #if defined(PSEUDO_DMA) && defined(UNSAFE)
2065         spin_lock_irq(instance->host_lock);
2066 #endif                          /* defined(REAL_DMA_POLL) */
2067         return foo;
2068 #endif                          /* def REAL_DMA */
2069 }
2070 #endif                          /* defined(REAL_DMA) | defined(PSEUDO_DMA) */
2071
2072 /*
2073  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
2074  *
2075  * Purpose : run through the various SCSI phases and do as the target 
2076  *      directs us to.  Operates on the currently connected command, 
2077  *      instance->connected.
2078  *
2079  * Inputs : instance, instance for which we are doing commands
2080  *
2081  * Side effects : SCSI things happen, the disconnected queue will be 
2082  *      modified if a command disconnects, *instance->connected will
2083  *      change.
2084  *
2085  * XXX Note : we need to watch for bus free or a reset condition here 
2086  *      to recover from an unexpected bus free condition.
2087  *
2088  * Locks: io_request_lock held by caller in IRQ mode
2089  */
2090
2091 static void NCR5380_information_transfer(struct Scsi_Host *instance) {
2092         NCR5380_local_declare();
2093         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)instance->hostdata;
2094         unsigned char msgout = NOP;
2095         int sink = 0;
2096         int len;
2097 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2098         int transfersize;
2099 #endif
2100         unsigned char *data;
2101         unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2102         Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2103         /* RvC: we need to set the end of the polling time */
2104         unsigned long poll_time = jiffies + USLEEP_POLL;
2105
2106         NCR5380_setup(instance);
2107
2108         while (1) {
2109                 tmp = NCR5380_read(STATUS_REG);
2110                 /* We only have a valid SCSI phase when REQ is asserted */
2111                 if (tmp & SR_REQ) {
2112                         phase = (tmp & PHASE_MASK);
2113                         if (phase != old_phase) {
2114                                 old_phase = phase;
2115                                 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
2116                         }
2117                         if (sink && (phase != PHASE_MSGOUT)) {
2118                                 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2119
2120                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
2121                                 while (NCR5380_read(STATUS_REG) & SR_REQ);
2122                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2123                                 sink = 0;
2124                                 continue;
2125                         }
2126                         switch (phase) {
2127                         case PHASE_DATAIN:
2128                         case PHASE_DATAOUT:
2129 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2130                                 printk("scsi%d : NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n", instance->host_no);
2131                                 sink = 1;
2132                                 do_abort(instance);
2133                                 cmd->result = DID_ERROR << 16;
2134                                 cmd->done(cmd);
2135                                 return;
2136 #endif
2137                                 /* 
2138                                  * If there is no room left in the current buffer in the
2139                                  * scatter-gather list, move onto the next one.
2140                                  */
2141
2142                                 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2143                                         ++cmd->SCp.buffer;
2144                                         --cmd->SCp.buffers_residual;
2145                                         cmd->SCp.this_residual = cmd->SCp.buffer->length;
2146                                         cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+
2147                                                        cmd->SCp.buffer->offset;
2148                                         dprintk(NDEBUG_INFORMATION, ("scsi%d : %d bytes and %d buffers left\n", instance->host_no, cmd->SCp.this_residual, cmd->SCp.buffers_residual));
2149                                 }
2150                                 /*
2151                                  * The preferred transfer method is going to be 
2152                                  * PSEUDO-DMA for systems that are strictly PIO,
2153                                  * since we can let the hardware do the handshaking.
2154                                  *
2155                                  * For this to work, we need to know the transfersize
2156                                  * ahead of time, since the pseudo-DMA code will sit
2157                                  * in an unconditional loop.
2158                                  */
2159
2160 #if defined(PSEUDO_DMA) || defined(REAL_DMA_POLL)
2161                                 /* KLL
2162                                  * PSEUDO_DMA is defined here. If this is the g_NCR5380
2163                                  * driver then it will always be defined, so the
2164                                  * FLAG_NO_PSEUDO_DMA is used to inhibit PDMA in the base
2165                                  * NCR5380 case.  I think this is a fairly clean solution.
2166                                  * We supplement these 2 if's with the flag.
2167                                  */
2168 #ifdef NCR5380_dma_xfer_len
2169                                 if (!cmd->device->borken && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && (transfersize = NCR5380_dma_xfer_len(instance, cmd)) != 0) {
2170 #else
2171                                 transfersize = cmd->transfersize;
2172
2173 #ifdef LIMIT_TRANSFERSIZE       /* If we have problems with interrupt service */
2174                                 if (transfersize > 512)
2175                                         transfersize = 512;
2176 #endif                          /* LIMIT_TRANSFERSIZE */
2177
2178                                 if (!cmd->device->borken && transfersize && !(hostdata->flags & FLAG_NO_PSEUDO_DMA) && cmd->SCp.this_residual && !(cmd->SCp.this_residual % transfersize)) {
2179                                         /* Limit transfers to 32K, for xx400 & xx406
2180                                          * pseudoDMA that transfers in 128 bytes blocks. */
2181                                         if (transfersize > 32 * 1024)
2182                                                 transfersize = 32 * 1024;
2183 #endif
2184                                         len = transfersize;
2185                                         if (NCR5380_transfer_dma(instance, &phase, &len, (unsigned char **) &cmd->SCp.ptr)) {
2186                                                 /*
2187                                                  * If the watchdog timer fires, all future accesses to this
2188                                                  * device will use the polled-IO.
2189                                                  */
2190                                                 scmd_printk(KERN_INFO, cmd,
2191                                                             "switching to slow handshake\n");
2192                                                 cmd->device->borken = 1;
2193                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2194                                                 sink = 1;
2195                                                 do_abort(instance);
2196                                                 cmd->result = DID_ERROR << 16;
2197                                                 cmd->done(cmd);
2198                                                 /* XXX - need to source or sink data here, as appropriate */
2199                                         } else
2200                                                 cmd->SCp.this_residual -= transfersize - len;
2201                                 } else
2202 #endif                          /* defined(PSEUDO_DMA) || defined(REAL_DMA_POLL) */
2203                                         NCR5380_transfer_pio(instance, &phase, (int *) &cmd->SCp.this_residual, (unsigned char **)
2204                                                              &cmd->SCp.ptr);
2205                                 break;
2206                         case PHASE_MSGIN:
2207                                 len = 1;
2208                                 data = &tmp;
2209                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2210                                 cmd->SCp.Message = tmp;
2211
2212                                 switch (tmp) {
2213                                         /*
2214                                          * Linking lets us reduce the time required to get the 
2215                                          * next command out to the device, hopefully this will
2216                                          * mean we don't waste another revolution due to the delays
2217                                          * required by ARBITRATION and another SELECTION.
2218                                          *
2219                                          * In the current implementation proposal, low level drivers
2220                                          * merely have to start the next command, pointed to by 
2221                                          * next_link, done() is called as with unlinked commands.
2222                                          */
2223 #ifdef LINKED
2224                                 case LINKED_CMD_COMPLETE:
2225                                 case LINKED_FLG_CMD_COMPLETE:
2226                                         /* Accept message by clearing ACK */
2227                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2228                                         dprintk(NDEBUG_LINKED, ("scsi%d : target %d lun %d linked command complete.\n", instance->host_no, cmd->device->id, cmd->device->lun));
2229                                         /* 
2230                                          * Sanity check : A linked command should only terminate with
2231                                          * one of these messages if there are more linked commands
2232                                          * available.
2233                                          */
2234                                         if (!cmd->next_link) {
2235                                                 printk("scsi%d : target %d lun %d linked command complete, no next_link\n" instance->host_no, cmd->device->id, cmd->device->lun);
2236                                                 sink = 1;
2237                                                 do_abort(instance);
2238                                                 return;
2239                                         }
2240                                         initialize_SCp(cmd->next_link);
2241                                         /* The next command is still part of this process */
2242                                         cmd->next_link->tag = cmd->tag;
2243                                         cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2244                                         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));
2245                                         collect_stats(hostdata, cmd);
2246                                         cmd->scsi_done(cmd);
2247                                         cmd = hostdata->connected;
2248                                         break;
2249 #endif                          /* def LINKED */
2250                                 case ABORT:
2251                                 case COMMAND_COMPLETE:
2252                                         /* Accept message by clearing ACK */
2253                                         sink = 1;
2254                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2255                                         hostdata->connected = NULL;
2256                                         dprintk(NDEBUG_QUEUES, ("scsi%d : command for target %d, lun %d completed\n", instance->host_no, cmd->device->id, cmd->device->lun));
2257                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2258
2259                                         /* 
2260                                          * I'm not sure what the correct thing to do here is : 
2261                                          * 
2262                                          * If the command that just executed is NOT a request 
2263                                          * sense, the obvious thing to do is to set the result
2264                                          * code to the values of the stored parameters.
2265                                          * 
2266                                          * If it was a REQUEST SENSE command, we need some way 
2267                                          * to differentiate between the failure code of the original
2268                                          * and the failure code of the REQUEST sense - the obvious
2269                                          * case is success, where we fall through and leave the result
2270                                          * code unchanged.
2271                                          * 
2272                                          * The non-obvious place is where the REQUEST SENSE failed 
2273                                          */
2274
2275                                         if (cmd->cmnd[0] != REQUEST_SENSE)
2276                                                 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2277                                         else if (status_byte(cmd->SCp.Status) != GOOD)
2278                                                 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2279
2280 #ifdef AUTOSENSE
2281                                         if ((cmd->cmnd[0] != REQUEST_SENSE) && (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2282                                                 dprintk(NDEBUG_AUTOSENSE, ("scsi%d : performing request sense\n", instance->host_no));
2283                                                 cmd->cmnd[0] = REQUEST_SENSE;
2284                                                 cmd->cmnd[1] &= 0xe0;
2285                                                 cmd->cmnd[2] = 0;
2286                                                 cmd->cmnd[3] = 0;
2287                                                 cmd->cmnd[4] = sizeof(cmd->sense_buffer);
2288                                                 cmd->cmnd[5] = 0;
2289
2290                                                 cmd->SCp.buffer = NULL;
2291                                                 cmd->SCp.buffers_residual = 0;
2292                                                 cmd->SCp.ptr = (char *) cmd->sense_buffer;
2293                                                 cmd->SCp.this_residual = sizeof(cmd->sense_buffer);
2294
2295                                                 LIST(cmd, hostdata->issue_queue);
2296                                                 cmd->host_scribble = (unsigned char *)
2297                                                     hostdata->issue_queue;
2298                                                 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2299                                                 dprintk(NDEBUG_QUEUES, ("scsi%d : REQUEST SENSE added to head of issue queue\n", instance->host_no));
2300                                         } else
2301 #endif                          /* def AUTOSENSE */
2302                                         {
2303                                                 collect_stats(hostdata, cmd);
2304                                                 cmd->scsi_done(cmd);
2305                                         }
2306
2307                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2308                                         /* 
2309                                          * Restore phase bits to 0 so an interrupted selection, 
2310                                          * arbitration can resume.
2311                                          */
2312                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2313
2314                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2315                                                 barrier();
2316                                         return;
2317                                 case MESSAGE_REJECT:
2318                                         /* Accept message by clearing ACK */
2319                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2320                                         switch (hostdata->last_message) {
2321                                         case HEAD_OF_QUEUE_TAG:
2322                                         case ORDERED_QUEUE_TAG:
2323                                         case SIMPLE_QUEUE_TAG:
2324                                                 cmd->device->simple_tags = 0;
2325                                                 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2326                                                 break;
2327                                         default:
2328                                                 break;
2329                                         }
2330                                 case DISCONNECT:{
2331                                                 /* Accept message by clearing ACK */
2332                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2333                                                 cmd->device->disconnect = 1;
2334                                                 LIST(cmd, hostdata->disconnected_queue);
2335                                                 cmd->host_scribble = (unsigned char *)
2336                                                     hostdata->disconnected_queue;
2337                                                 hostdata->connected = NULL;
2338                                                 hostdata->disconnected_queue = cmd;
2339                                                 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));
2340                                                 /* 
2341                                                  * Restore phase bits to 0 so an interrupted selection, 
2342                                                  * arbitration can resume.
2343                                                  */
2344                                                 NCR5380_write(TARGET_COMMAND_REG, 0);
2345
2346                                                 /* Enable reselect interrupts */
2347                                                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2348                                                 /* Wait for bus free to avoid nasty timeouts - FIXME timeout !*/
2349                                                 /* NCR538_poll_politely(instance, STATUS_REG, SR_BSY, 0, 30 * HZ); */
2350                                                 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2351                                                         barrier();
2352                                                 return;
2353                                         }
2354                                         /* 
2355                                          * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2356                                          * operation, in violation of the SCSI spec so we can safely 
2357                                          * ignore SAVE/RESTORE pointers calls.
2358                                          *
2359                                          * Unfortunately, some disks violate the SCSI spec and 
2360                                          * don't issue the required SAVE_POINTERS message before
2361                                          * disconnecting, and we have to break spec to remain 
2362                                          * compatible.
2363                                          */
2364                                 case SAVE_POINTERS:
2365                                 case RESTORE_POINTERS:
2366                                         /* Accept message by clearing ACK */
2367                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2368                                         break;
2369                                 case EXTENDED_MESSAGE:
2370 /* 
2371  * Extended messages are sent in the following format :
2372  * Byte         
2373  * 0            EXTENDED_MESSAGE == 1
2374  * 1            length (includes one byte for code, doesn't 
2375  *              include first two bytes)
2376  * 2            code
2377  * 3..length+1  arguments
2378  *
2379  * Start the extended message buffer with the EXTENDED_MESSAGE
2380  * byte, since spi_print_msg() wants the whole thing.  
2381  */
2382                                         extended_msg[0] = EXTENDED_MESSAGE;
2383                                         /* Accept first byte by clearing ACK */
2384                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2385                                         dprintk(NDEBUG_EXTENDED, ("scsi%d : receiving extended message\n", instance->host_no));
2386
2387                                         len = 2;
2388                                         data = extended_msg + 1;
2389                                         phase = PHASE_MSGIN;
2390                                         NCR5380_transfer_pio(instance, &phase, &len, &data);
2391
2392                                         dprintk(NDEBUG_EXTENDED, ("scsi%d : length=%d, code=0x%02x\n", instance->host_no, (int) extended_msg[1], (int) extended_msg[2]));
2393
2394                                         if (!len && extended_msg[1] <= (sizeof(extended_msg) - 1)) {
2395                                                 /* Accept third byte by clearing ACK */
2396                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2397                                                 len = extended_msg[1] - 1;
2398                                                 data = extended_msg + 3;
2399                                                 phase = PHASE_MSGIN;
2400
2401                                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2402                                                 dprintk(NDEBUG_EXTENDED, ("scsi%d : message received, residual %d\n", instance->host_no, len));
2403
2404                                                 switch (extended_msg[2]) {
2405                                                 case EXTENDED_SDTR:
2406                                                 case EXTENDED_WDTR:
2407                                                 case EXTENDED_MODIFY_DATA_POINTER:
2408                                                 case EXTENDED_EXTENDED_IDENTIFY:
2409                                                         tmp = 0;
2410                                                 }
2411                                         } else if (len) {
2412                                                 printk("scsi%d: error receiving extended message\n", instance->host_no);
2413                                                 tmp = 0;
2414                                         } else {
2415                                                 printk("scsi%d: extended message code %02x length %d is too long\n", instance->host_no, extended_msg[2], extended_msg[1]);
2416                                                 tmp = 0;
2417                                         }
2418                                         /* Fall through to reject message */
2419
2420                                         /* 
2421                                          * If we get something weird that we aren't expecting, 
2422                                          * reject it.
2423                                          */
2424                                 default:
2425                                         if (!tmp) {
2426                                                 printk("scsi%d: rejecting message ", instance->host_no);
2427                                                 spi_print_msg(extended_msg);
2428                                                 printk("\n");
2429                                         } else if (tmp != EXTENDED_MESSAGE)
2430                                                 scmd_printk(KERN_INFO, cmd,
2431                                                         "rejecting unknown message %02x\n",tmp);
2432                                         else
2433                                                 scmd_printk(KERN_INFO, cmd,
2434                                                         "rejecting unknown extended message code %02x, length %d\n", extended_msg[1], extended_msg[0]);
2435
2436                                         msgout = MESSAGE_REJECT;
2437                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2438                                         break;
2439                                 }       /* switch (tmp) */
2440                                 break;
2441                         case PHASE_MSGOUT:
2442                                 len = 1;
2443                                 data = &msgout;
2444                                 hostdata->last_message = msgout;
2445                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2446                                 if (msgout == ABORT) {
2447                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2448                                         hostdata->connected = NULL;
2449                                         cmd->result = DID_ERROR << 16;
2450                                         collect_stats(hostdata, cmd);
2451                                         cmd->scsi_done(cmd);
2452                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2453                                         return;
2454                                 }
2455                                 msgout = NOP;
2456                                 break;
2457                         case PHASE_CMDOUT:
2458                                 len = cmd->cmd_len;
2459                                 data = cmd->cmnd;
2460                                 /* 
2461                                  * XXX for performance reasons, on machines with a 
2462                                  * PSEUDO-DMA architecture we should probably 
2463                                  * use the dma transfer function.  
2464                                  */
2465                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2466                                 if (!cmd->device->disconnect && should_disconnect(cmd->cmnd[0])) {
2467                                         NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2468                                         dprintk(NDEBUG_USLEEP, ("scsi%d : issued command, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2469                                         return;
2470                                 }
2471                                 break;
2472                         case PHASE_STATIN:
2473                                 len = 1;
2474                                 data = &tmp;
2475                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2476                                 cmd->SCp.Status = tmp;
2477                                 break;
2478                         default:
2479                                 printk("scsi%d : unknown phase\n", instance->host_no);
2480                                 NCR5380_dprint(NDEBUG_ALL, instance);
2481                         }       /* switch(phase) */
2482                 }               /* if (tmp * SR_REQ) */
2483                 else {
2484                         /* RvC: go to sleep if polling time expired
2485                          */
2486                         if (!cmd->device->disconnect && time_after_eq(jiffies, poll_time)) {
2487                                 NCR5380_set_timer(hostdata, USLEEP_SLEEP);
2488                                 dprintk(NDEBUG_USLEEP, ("scsi%d : poll timed out, sleeping until %ul\n", instance->host_no, hostdata->time_expires));
2489                                 return;
2490                         }
2491                 }
2492         }                       /* while (1) */
2493 }
2494
2495 /*
2496  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2497  *
2498  * Purpose : does reselection, initializing the instance->connected 
2499  *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q 
2500  *      nexus has been reestablished,
2501  *      
2502  * Inputs : instance - this instance of the NCR5380.
2503  *
2504  * Locks: io_request_lock held by caller if IRQ driven
2505  */
2506
2507 static void NCR5380_reselect(struct Scsi_Host *instance) {
2508         NCR5380_local_declare();
2509         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *)
2510          instance->hostdata;
2511         unsigned char target_mask;
2512         unsigned char lun, phase;
2513         int len;
2514         unsigned char msg[3];
2515         unsigned char *data;
2516         Scsi_Cmnd *tmp = NULL, *prev;
2517         int abort = 0;
2518         NCR5380_setup(instance);
2519
2520         /*
2521          * Disable arbitration, etc. since the host adapter obviously
2522          * lost, and tell an interrupted NCR5380_select() to restart.
2523          */
2524
2525         NCR5380_write(MODE_REG, MR_BASE);
2526         hostdata->restart_select = 1;
2527
2528         target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2529         dprintk(NDEBUG_SELECTION, ("scsi%d : reselect\n", instance->host_no));
2530
2531         /* 
2532          * At this point, we have detected that our SCSI ID is on the bus,
2533          * SEL is true and BSY was false for at least one bus settle delay
2534          * (400 ns).
2535          *
2536          * We must assert BSY ourselves, until the target drops the SEL
2537          * signal.
2538          */
2539
2540         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2541
2542         /* FIXME: timeout too long, must fail to workqueue */   
2543         if(NCR5380_poll_politely(instance, STATUS_REG, SR_SEL, 0, 2*HZ)<0)
2544                 abort = 1;
2545                 
2546         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2547
2548         /*
2549          * Wait for target to go into MSGIN.
2550          * FIXME: timeout needed and fail to work queeu
2551          */
2552
2553         if(NCR5380_poll_politely(instance, STATUS_REG, SR_REQ, SR_REQ, 2*HZ))
2554                 abort = 1;
2555
2556         len = 1;
2557         data = msg;
2558         phase = PHASE_MSGIN;
2559         NCR5380_transfer_pio(instance, &phase, &len, &data);
2560
2561         if (!(msg[0] & 0x80)) {
2562                 printk(KERN_ERR "scsi%d : expecting IDENTIFY message, got ", instance->host_no);
2563                 spi_print_msg(msg);
2564                 abort = 1;
2565         } else {
2566                 /* Accept message by clearing ACK */
2567                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2568                 lun = (msg[0] & 0x07);
2569
2570                 /* 
2571                  * We need to add code for SCSI-II to track which devices have
2572                  * I_T_L_Q nexuses established, and which have simple I_T_L
2573                  * nexuses so we can chose to do additional data transfer.
2574                  */
2575
2576                 /* 
2577                  * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we 
2578                  * just reestablished, and remove it from the disconnected queue.
2579                  */
2580
2581
2582                 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; tmp; prev = tmp, tmp = (Scsi_Cmnd *) tmp->host_scribble)
2583                         if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2584                             ) {
2585                                 if (prev) {
2586                                         REMOVE(prev, prev->host_scribble, tmp, tmp->host_scribble);
2587                                         prev->host_scribble = tmp->host_scribble;
2588                                 } else {
2589                                         REMOVE(-1, hostdata->disconnected_queue, tmp, tmp->host_scribble);
2590                                         hostdata->disconnected_queue = (Scsi_Cmnd *) tmp->host_scribble;
2591                                 }
2592                                 tmp->host_scribble = NULL;
2593                                 break;
2594                         }
2595                 if (!tmp) {
2596                         printk(KERN_ERR "scsi%d : warning : target bitmask %02x lun %d not in disconnect_queue.\n", instance->host_no, target_mask, lun);
2597                         /* 
2598                          * Since we have an established nexus that we can't do anything with,
2599                          * we must abort it.  
2600                          */
2601                         abort = 1;
2602                 }
2603         }
2604
2605         if (abort) {
2606                 do_abort(instance);
2607         } else {
2608                 hostdata->connected = tmp;
2609                 dprintk(NDEBUG_RESELECTION, ("scsi%d : nexus established, target = %d, lun = %d, tag = %d\n", instance->host_no, tmp->target, tmp->lun, tmp->tag));
2610         }
2611 }
2612
2613 /*
2614  * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
2615  *
2616  * Purpose : called by interrupt handler when DMA finishes or a phase
2617  *      mismatch occurs (which would finish the DMA transfer).  
2618  *
2619  * Inputs : instance - this instance of the NCR5380.
2620  *
2621  * Returns : pointer to the Scsi_Cmnd structure for which the I_T_L
2622  *      nexus has been reestablished, on failure NULL is returned.
2623  */
2624
2625 #ifdef REAL_DMA
2626 static void NCR5380_dma_complete(NCR5380_instance * instance) {
2627         NCR5380_local_declare();
2628         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2629         int transferred;
2630         NCR5380_setup(instance);
2631
2632         /*
2633          * XXX this might not be right.
2634          *
2635          * Wait for final byte to transfer, ie wait for ACK to go false.
2636          *
2637          * We should use the Last Byte Sent bit, unfortunately this is 
2638          * not available on the 5380/5381 (only the various CMOS chips)
2639          *
2640          * FIXME: timeout, and need to handle long timeout/irq case
2641          */
2642
2643         NCR5380_poll_politely(instance, BUS_AND_STATUS_REG, BASR_ACK, 0, 5*HZ);
2644
2645         NCR5380_write(MODE_REG, MR_BASE);
2646         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2647
2648         /*
2649          * The only places we should see a phase mismatch and have to send
2650          * data from the same set of pointers will be the data transfer
2651          * phases.  So, residual, requested length are only important here.
2652          */
2653
2654         if (!(hostdata->connected->SCp.phase & SR_CD)) {
2655                 transferred = instance->dmalen - NCR5380_dma_residual();
2656                 hostdata->connected->SCp.this_residual -= transferred;
2657                 hostdata->connected->SCp.ptr += transferred;
2658         }
2659 }
2660 #endif                          /* def REAL_DMA */
2661
2662 /*
2663  * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2664  *
2665  * Purpose : abort a command
2666  *
2667  * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the 
2668  *      host byte of the result field to, if zero DID_ABORTED is 
2669  *      used.
2670  *
2671  * Returns : 0 - success, -1 on failure.
2672  *
2673  *      XXX - there is no way to abort the command that is currently 
2674  *      connected, you have to wait for it to complete.  If this is 
2675  *      a problem, we could implement longjmp() / setjmp(), setjmp()
2676  *      called where the loop started in NCR5380_main().
2677  *
2678  * Locks: host lock taken by caller
2679  */
2680
2681 static int NCR5380_abort(Scsi_Cmnd * cmd) {
2682         NCR5380_local_declare();
2683         struct Scsi_Host *instance = cmd->device->host;
2684         struct NCR5380_hostdata *hostdata = (struct NCR5380_hostdata *) instance->hostdata;
2685         Scsi_Cmnd *tmp, **prev;
2686         
2687         printk(KERN_WARNING "scsi%d : aborting command\n", instance->host_no);
2688         scsi_print_command(cmd);
2689
2690         NCR5380_print_status(instance);
2691
2692         NCR5380_setup(instance);
2693
2694         dprintk(NDEBUG_ABORT, ("scsi%d : abort called\n", instance->host_no));
2695         dprintk(NDEBUG_ABORT, ("        basr 0x%X, sr 0x%X\n", NCR5380_read(BUS_AND_STATUS_REG), NCR5380_read(STATUS_REG)));
2696
2697 #if 0
2698 /*
2699  * Case 1 : If the command is the currently executing command, 
2700  * we'll set the aborted flag and return control so that 
2701  * information transfer routine can exit cleanly.
2702  */
2703
2704         if (hostdata->connected == cmd) {
2705                 dprintk(NDEBUG_ABORT, ("scsi%d : aborting connected command\n", instance->host_no));
2706                 hostdata->aborted = 1;
2707 /*
2708  * We should perform BSY checking, and make sure we haven't slipped
2709  * into BUS FREE.
2710  */
2711
2712                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN);
2713 /* 
2714  * Since we can't change phases until we've completed the current 
2715  * handshake, we have to source or sink a byte of data if the current
2716  * phase is not MSGOUT.
2717  */
2718
2719 /* 
2720  * Return control to the executing NCR drive so we can clear the
2721  * aborted flag and get back into our main loop.
2722  */
2723
2724                 return 0;
2725         }
2726 #endif
2727
2728 /* 
2729  * Case 2 : If the command hasn't been issued yet, we simply remove it 
2730  *          from the issue queue.
2731  */
2732  
2733         dprintk(NDEBUG_ABORT, ("scsi%d : abort going into loop.\n", instance->host_no));
2734         for (prev = (Scsi_Cmnd **) & (hostdata->issue_queue), tmp = (Scsi_Cmnd *) hostdata->issue_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
2735                 if (cmd == tmp) {
2736                         REMOVE(5, *prev, tmp, tmp->host_scribble);
2737                         (*prev) = (Scsi_Cmnd *) tmp->host_scribble;
2738                         tmp->host_scribble = NULL;
2739                         tmp->result = DID_ABORT << 16;
2740                         dprintk(NDEBUG_ABORT, ("scsi%d : abort removed command from issue queue.\n", instance->host_no));
2741                         tmp->done(tmp);
2742                         return SUCCESS;
2743                 }
2744 #if (NDEBUG  & NDEBUG_ABORT)
2745         /* KLL */
2746                 else if (prev == tmp)
2747                         printk(KERN_ERR "scsi%d : LOOP\n", instance->host_no);
2748 #endif
2749
2750 /* 
2751  * Case 3 : If any commands are connected, we're going to fail the abort
2752  *          and let the high level SCSI driver retry at a later time or 
2753  *          issue a reset.
2754  *
2755  *          Timeouts, and therefore aborted commands, will be highly unlikely
2756  *          and handling them cleanly in this situation would make the common
2757  *          case of noresets less efficient, and would pollute our code.  So,
2758  *          we fail.
2759  */
2760
2761         if (hostdata->connected) {
2762                 dprintk(NDEBUG_ABORT, ("scsi%d : abort failed, command connected.\n", instance->host_no));
2763                 return FAILED;
2764         }
2765 /*
2766  * Case 4: If the command is currently disconnected from the bus, and 
2767  *      there are no connected commands, we reconnect the I_T_L or 
2768  *      I_T_L_Q nexus associated with it, go into message out, and send 
2769  *      an abort message.
2770  *
2771  * This case is especially ugly. In order to reestablish the nexus, we
2772  * need to call NCR5380_select().  The easiest way to implement this 
2773  * function was to abort if the bus was busy, and let the interrupt
2774  * handler triggered on the SEL for reselect take care of lost arbitrations
2775  * where necessary, meaning interrupts need to be enabled.
2776  *
2777  * When interrupts are enabled, the queues may change - so we 
2778  * can't remove it from the disconnected queue before selecting it
2779  * because that could cause a failure in hashing the nexus if that 
2780  * device reselected.
2781  * 
2782  * Since the queues may change, we can't use the pointers from when we
2783  * first locate it.
2784  *
2785  * So, we must first locate the command, and if NCR5380_select()
2786  * succeeds, then issue the abort, relocate the command and remove
2787  * it from the disconnected queue.
2788  */
2789
2790         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; tmp = (Scsi_Cmnd *) tmp->host_scribble)
2791                 if (cmd == tmp) {
2792                         dprintk(NDEBUG_ABORT, ("scsi%d : aborting disconnected command.\n", instance->host_no));
2793
2794                         if (NCR5380_select(instance, cmd, (int) cmd->tag))
2795                                 return FAILED;
2796                         dprintk(NDEBUG_ABORT, ("scsi%d : nexus reestablished.\n", instance->host_no));
2797
2798                         do_abort(instance);
2799
2800                         for (prev = (Scsi_Cmnd **) & (hostdata->disconnected_queue), tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; prev = (Scsi_Cmnd **) & (tmp->host_scribble), tmp = (Scsi_Cmnd *) tmp->host_scribble)
2801                                 if (cmd == tmp) {
2802                                         REMOVE(5, *prev, tmp, tmp->host_scribble);
2803                                         *prev = (Scsi_Cmnd *) tmp->host_scribble;
2804                                         tmp->host_scribble = NULL;
2805                                         tmp->result = DID_ABORT << 16;
2806                                         tmp->done(tmp);
2807                                         return SUCCESS;
2808                                 }
2809                 }
2810 /*
2811  * Case 5 : If we reached this point, the command was not found in any of 
2812  *          the queues.
2813  *
2814  * We probably reached this point because of an unlikely race condition
2815  * between the command completing successfully and the abortion code,
2816  * so we won't panic, but we will notify the user in case something really
2817  * broke.
2818  */
2819         printk(KERN_WARNING "scsi%d : warning : SCSI command probably completed successfully\n"
2820                         "         before abortion\n", instance->host_no);
2821         return FAILED;
2822 }
2823
2824
2825 /* 
2826  * Function : int NCR5380_bus_reset (Scsi_Cmnd *cmd)
2827  * 
2828  * Purpose : reset the SCSI bus.
2829  *
2830  * Returns : SUCCESS
2831  *
2832  * Locks: host lock taken by caller
2833  */
2834
2835 static int NCR5380_bus_reset(Scsi_Cmnd * cmd)
2836 {
2837         struct Scsi_Host *instance = cmd->device->host;
2838
2839         NCR5380_local_declare();
2840         NCR5380_setup(instance);
2841         NCR5380_print_status(instance);
2842
2843         spin_lock_irq(instance->host_lock);
2844         do_reset(instance);
2845         spin_unlock_irq(instance->host_lock);
2846
2847         return SUCCESS;
2848 }