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sun3_NCR5380.c
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1 /* sun3_NCR5380.c -- adapted from atari_NCR5380.c for the sun3 by
2  Sam Creasey. */
3 /*
4  * NCR 5380 generic driver routines. These should make it *trivial*
5  * to implement 5380 SCSI drivers under Linux with a non-trantor
6  * architecture.
7  *
8  * Note that these routines also work with NR53c400 family chips.
9  *
10  * Copyright 1993, Drew Eckhardt
11  * Visionary Computing
12  * (Unix and Linux consulting and custom programming)
14  * +1 (303) 666-5836
15  *
16  * DISTRIBUTION RELEASE 6.
17  *
18  * For more information, please consult
19  *
20  * NCR 5380 Family
21  * SCSI Protocol Controller
22  * Databook
23  *
24  * NCR Microelectronics
25  * 1635 Aeroplaza Drive
26  * Colorado Springs, CO 80916
27  * 1+ (719) 578-3400
28  * 1+ (800) 334-5454
29  */
30 
31 /*
32  * ++roman: To port the 5380 driver to the Atari, I had to do some changes in
33  * this file, too:
34  *
35  * - Some of the debug statements were incorrect (undefined variables and the
36  * like). I fixed that.
37  *
38  * - In information_transfer(), I think a #ifdef was wrong. Looking at the
39  * possible DMA transfer size should also happen for REAL_DMA. I added this
40  * in the #if statement.
41  *
42  * - When using real DMA, information_transfer() should return in a DATAOUT
43  * phase after starting the DMA. It has nothing more to do.
44  *
45  * - The interrupt service routine should run main after end of DMA, too (not
46  * only after RESELECTION interrupts). Additionally, it should _not_ test
47  * for more interrupts after running main, since a DMA process may have
48  * been started and interrupts are turned on now. The new int could happen
49  * inside the execution of NCR5380_intr(), leading to recursive
50  * calls.
51  *
52  * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA
53  * and USLEEP, because these were messing up readability and will never be
54  * needed for Atari SCSI.
55  *
56  * - I've revised the NCR5380_main() calling scheme (relax the 'main_running'
57  * stuff), and 'main' is executed in a bottom half if awoken by an
58  * interrupt.
59  *
60  * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..."
61  * constructs. In my eyes, this made the source rather unreadable, so I
62  * finally replaced that by the *_PRINTK() macros.
63  *
64  */
65 #include <scsi/scsi_dbg.h>
67 
68 /*
69  * Further development / testing that should be done :
70  * 1. Test linked command handling code after Eric is ready with
71  * the high level code.
72  */
73 
74 #if (NDEBUG & NDEBUG_LISTS)
75 #define LIST(x,y) \
76  { printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); \
77  if ((x)==(y)) udelay(5); }
78 #define REMOVE(w,x,y,z) \
79  { printk("LINE:%d Removing: %p->%p %p->%p \n", __LINE__, \
80  (void*)(w), (void*)(x), (void*)(y), (void*)(z)); \
81  if ((x)==(y)) udelay(5); }
82 #else
83 #define LIST(x,y)
84 #define REMOVE(w,x,y,z)
85 #endif
86 
87 #ifndef notyet
88 #undef LINKED
89 #endif
90 
91 /*
92  * Design
93  * Issues :
94  *
95  * The other Linux SCSI drivers were written when Linux was Intel PC-only,
96  * and specifically for each board rather than each chip. This makes their
97  * adaptation to platforms like the Mac (Some of which use NCR5380's)
98  * more difficult than it has to be.
99  *
100  * Also, many of the SCSI drivers were written before the command queuing
101  * routines were implemented, meaning their implementations of queued
102  * commands were hacked on rather than designed in from the start.
103  *
104  * When I designed the Linux SCSI drivers I figured that
105  * while having two different SCSI boards in a system might be useful
106  * for debugging things, two of the same type wouldn't be used.
107  * Well, I was wrong and a number of users have mailed me about running
108  * multiple high-performance SCSI boards in a server.
109  *
110  * Finally, when I get questions from users, I have no idea what
111  * revision of my driver they are running.
112  *
113  * This driver attempts to address these problems :
114  * This is a generic 5380 driver. To use it on a different platform,
115  * one simply writes appropriate system specific macros (ie, data
116  * transfer - some PC's will use the I/O bus, 68K's must use
117  * memory mapped) and drops this file in their 'C' wrapper.
118  *
119  * As far as command queueing, two queues are maintained for
120  * each 5380 in the system - commands that haven't been issued yet,
121  * and commands that are currently executing. This means that an
122  * unlimited number of commands may be queued, letting
123  * more commands propagate from the higher driver levels giving higher
124  * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
125  * allowing multiple commands to propagate all the way to a SCSI-II device
126  * while a command is already executing.
127  *
128  * To solve the multiple-boards-in-the-same-system problem,
129  * there is a separate instance structure for each instance
130  * of a 5380 in the system. So, multiple NCR5380 drivers will
131  * be able to coexist with appropriate changes to the high level
132  * SCSI code.
133  *
134  * A NCR5380_PUBLIC_REVISION macro is provided, with the release
135  * number (updated for each public release) printed by the
136  * NCR5380_print_options command, which should be called from the
137  * wrapper detect function, so that I know what release of the driver
138  * users are using.
139  *
140  * Issues specific to the NCR5380 :
141  *
142  * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
143  * piece of hardware that requires you to sit in a loop polling for
144  * the REQ signal as long as you are connected. Some devices are
145  * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
146  * while doing long seek operations.
147  *
148  * The workaround for this is to keep track of devices that have
149  * disconnected. If the device hasn't disconnected, for commands that
150  * should disconnect, we do something like
151  *
152  * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
153  *
154  * Some tweaking of N and M needs to be done. An algorithm based
155  * on "time to data" would give the best results as long as short time
156  * to datas (ie, on the same track) were considered, however these
157  * broken devices are the exception rather than the rule and I'd rather
158  * spend my time optimizing for the normal case.
159  *
160  * Architecture :
161  *
162  * At the heart of the design is a coroutine, NCR5380_main,
163  * which is started when not running by the interrupt handler,
164  * timer, and queue command function. It attempts to establish
165  * I_T_L or I_T_L_Q nexuses by removing the commands from the
166  * issue queue and calling NCR5380_select() if a nexus
167  * is not established.
168  *
169  * Once a nexus is established, the NCR5380_information_transfer()
170  * phase goes through the various phases as instructed by the target.
171  * if the target goes into MSG IN and sends a DISCONNECT message,
172  * the command structure is placed into the per instance disconnected
173  * queue, and NCR5380_main tries to find more work. If USLEEP
174  * was defined, and the target is idle for too long, the system
175  * will try to sleep.
176  *
177  * If a command has disconnected, eventually an interrupt will trigger,
178  * calling NCR5380_intr() which will in turn call NCR5380_reselect
179  * to reestablish a nexus. This will run main if necessary.
180  *
181  * On command termination, the done function will be called as
182  * appropriate.
183  *
184  * SCSI pointers are maintained in the SCp field of SCSI command
185  * structures, being initialized after the command is connected
186  * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
187  * Note that in violation of the standard, an implicit SAVE POINTERS operation
188  * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
189  */
190 
191 /*
192  * Using this file :
193  * This file a skeleton Linux SCSI driver for the NCR 5380 series
194  * of chips. To use it, you write an architecture specific functions
195  * and macros and include this file in your driver.
196  *
197  * These macros control options :
198  * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
199  * for commands that return with a CHECK CONDITION status.
200  *
201  * LINKED - if defined, linked commands are supported.
202  *
203  * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
204  *
205  * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
206  *
207  * These macros MUST be defined :
208  *
209  * NCR5380_read(register) - read from the specified register
210  *
211  * NCR5380_write(register, value) - write to the specific register
212  *
213  * Either real DMA *or* pseudo DMA may be implemented
214  * REAL functions :
215  * NCR5380_REAL_DMA should be defined if real DMA is to be used.
216  * Note that the DMA setup functions should return the number of bytes
217  * that they were able to program the controller for.
218  *
219  * Also note that generic i386/PC versions of these macros are
220  * available as NCR5380_i386_dma_write_setup,
221  * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
222  *
223  * NCR5380_dma_write_setup(instance, src, count) - initialize
224  * NCR5380_dma_read_setup(instance, dst, count) - initialize
225  * NCR5380_dma_residual(instance); - residual count
226  *
227  * PSEUDO functions :
228  * NCR5380_pwrite(instance, src, count)
229  * NCR5380_pread(instance, dst, count);
230  *
231  * If nothing specific to this implementation needs doing (ie, with external
232  * hardware), you must also define
233  *
234  * NCR5380_queue_command
235  * NCR5380_reset
236  * NCR5380_abort
237  * NCR5380_proc_info
238  *
239  * to be the global entry points into the specific driver, ie
240  * #define NCR5380_queue_command t128_queue_command.
241  *
242  * If this is not done, the routines will be defined as static functions
243  * with the NCR5380* names and the user must provide a globally
244  * accessible wrapper function.
245  *
246  * The generic driver is initialized by calling NCR5380_init(instance),
247  * after setting the appropriate host specific fields and ID. If the
248  * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
249  * possible) function may be used. Before the specific driver initialization
250  * code finishes, NCR5380_print_options should be called.
251  */
252 
253 static struct Scsi_Host *first_instance = NULL;
254 static struct scsi_host_template *the_template = NULL;
255 
256 /* Macros ease life... :-) */
257 #define SETUP_HOSTDATA(in) \
258  struct NCR5380_hostdata *hostdata = \
259  (struct NCR5380_hostdata *)(in)->hostdata
260 #define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)
261 
262 #define NEXT(cmd) ((struct scsi_cmnd *)(cmd)->host_scribble)
263 #define SET_NEXT(cmd, next) ((cmd)->host_scribble = (void *)(next))
264 #define NEXTADDR(cmd) ((struct scsi_cmnd **)&((cmd)->host_scribble))
265 
266 #define HOSTNO instance->host_no
267 #define H_NO(cmd) (cmd)->device->host->host_no
268 
269 #define SGADDR(buffer) (void *)(((unsigned long)sg_virt(((buffer)))))
270 
271 #ifdef SUPPORT_TAGS
272 
273 /*
274  * Functions for handling tagged queuing
275  * =====================================
276  *
277  * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
278  *
279  * Using consecutive numbers for the tags is no good idea in my eyes. There
280  * could be wrong re-usings if the counter (8 bit!) wraps and some early
281  * command has been preempted for a long time. My solution: a bitfield for
282  * remembering used tags.
283  *
284  * There's also the problem that each target has a certain queue size, but we
285  * cannot know it in advance :-( We just see a QUEUE_FULL status being
286  * returned. So, in this case, the driver internal queue size assumption is
287  * reduced to the number of active tags if QUEUE_FULL is returned by the
288  * target. The command is returned to the mid-level, but with status changed
289  * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL
290  * correctly.
291  *
292  * We're also not allowed running tagged commands as long as an untagged
293  * command is active. And REQUEST SENSE commands after a contingent allegiance
294  * condition _must_ be untagged. To keep track whether an untagged command has
295  * been issued, the host->busy array is still employed, as it is without
296  * support for tagged queuing.
297  *
298  * One could suspect that there are possible race conditions between
299  * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
300  * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
301  * which already guaranteed to be running at most once. It is also the only
302  * place where tags/LUNs are allocated. So no other allocation can slip
303  * between that pair, there could only happen a reselection, which can free a
304  * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
305  * important: the tag bit must be cleared before 'nr_allocated' is decreased.
306  */
307 
308 /* -1 for TAG_NONE is not possible with unsigned char cmd->tag */
309 #undef TAG_NONE
310 #define TAG_NONE 0xff
311 
312 /* For the m68k, the number of bits in 'allocated' must be a multiple of 32! */
313 #if (MAX_TAGS % 32) != 0
314 #error "MAX_TAGS must be a multiple of 32!"
315 #endif
316 
317 typedef struct {
318  char allocated[MAX_TAGS/8];
319  int nr_allocated;
320  int queue_size;
321 } TAG_ALLOC;
322 
323 static TAG_ALLOC TagAlloc[8][8]; /* 8 targets and 8 LUNs */
324 
325 
326 static void __init init_tags( void )
327 {
328  int target, lun;
329  TAG_ALLOC *ta;
330 
331  if (!setup_use_tagged_queuing)
332  return;
333 
334  for( target = 0; target < 8; ++target ) {
335  for( lun = 0; lun < 8; ++lun ) {
336  ta = &TagAlloc[target][lun];
337  memset( &ta->allocated, 0, MAX_TAGS/8 );
338  ta->nr_allocated = 0;
339  /* At the beginning, assume the maximum queue size we could
340  * support (MAX_TAGS). This value will be decreased if the target
341  * returns QUEUE_FULL status.
342  */
343  ta->queue_size = MAX_TAGS;
344  }
345  }
346 }
347 
348 
349 /* Check if we can issue a command to this LUN: First see if the LUN is marked
350  * busy by an untagged command. If the command should use tagged queuing, also
351  * check that there is a free tag and the target's queue won't overflow. This
352  * function should be called with interrupts disabled to avoid race
353  * conditions.
354  */
355 
356 static int is_lun_busy(struct scsi_cmnd *cmd, int should_be_tagged)
357 {
358  SETUP_HOSTDATA(cmd->device->host);
359 
360  if (hostdata->busy[cmd->device->id] & (1 << cmd->device->lun))
361  return( 1 );
362  if (!should_be_tagged ||
363  !setup_use_tagged_queuing || !cmd->device->tagged_supported)
364  return( 0 );
365  if (TagAlloc[cmd->device->id][cmd->device->lun].nr_allocated >=
366  TagAlloc[cmd->device->id][cmd->device->lun].queue_size ) {
367  TAG_PRINTK( "scsi%d: target %d lun %d: no free tags\n",
368  H_NO(cmd), cmd->device->id, cmd->device->lun );
369  return( 1 );
370  }
371  return( 0 );
372 }
373 
374 
375 /* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
376  * must be called before!), or reserve the LUN in 'busy' if the command is
377  * untagged.
378  */
379 
380 static void cmd_get_tag(struct scsi_cmnd *cmd, int should_be_tagged)
381 {
382  SETUP_HOSTDATA(cmd->device->host);
383 
384  /* If we or the target don't support tagged queuing, allocate the LUN for
385  * an untagged command.
386  */
387  if (!should_be_tagged ||
388  !setup_use_tagged_queuing || !cmd->device->tagged_supported) {
389  cmd->tag = TAG_NONE;
390  hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
391  TAG_PRINTK( "scsi%d: target %d lun %d now allocated by untagged "
392  "command\n", H_NO(cmd), cmd->device->id, cmd->device->lun );
393  }
394  else {
395  TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
396 
397  cmd->tag = find_first_zero_bit( &ta->allocated, MAX_TAGS );
398  set_bit( cmd->tag, &ta->allocated );
399  ta->nr_allocated++;
400  TAG_PRINTK( "scsi%d: using tag %d for target %d lun %d "
401  "(now %d tags in use)\n",
402  H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun,
403  ta->nr_allocated );
404  }
405 }
406 
407 
408 /* Mark the tag of command 'cmd' as free, or in case of an untagged command,
409  * unlock the LUN.
410  */
411 
412 static void cmd_free_tag(struct scsi_cmnd *cmd)
413 {
414  SETUP_HOSTDATA(cmd->device->host);
415 
416  if (cmd->tag == TAG_NONE) {
417  hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
418  TAG_PRINTK( "scsi%d: target %d lun %d untagged cmd finished\n",
419  H_NO(cmd), cmd->device->id, cmd->device->lun );
420  }
421  else if (cmd->tag >= MAX_TAGS) {
422  printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n",
423  H_NO(cmd), cmd->tag );
424  }
425  else {
426  TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
427  clear_bit( cmd->tag, &ta->allocated );
428  ta->nr_allocated--;
429  TAG_PRINTK( "scsi%d: freed tag %d for target %d lun %d\n",
430  H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun );
431  }
432 }
433 
434 
435 static void free_all_tags( void )
436 {
437  int target, lun;
438  TAG_ALLOC *ta;
439 
440  if (!setup_use_tagged_queuing)
441  return;
442 
443  for( target = 0; target < 8; ++target ) {
444  for( lun = 0; lun < 8; ++lun ) {
445  ta = &TagAlloc[target][lun];
446  memset( &ta->allocated, 0, MAX_TAGS/8 );
447  ta->nr_allocated = 0;
448  }
449  }
450 }
451 
452 #endif /* SUPPORT_TAGS */
453 
454 
455 /*
456  * Function : void initialize_SCp(struct scsi_cmnd *cmd)
457  *
458  * Purpose : initialize the saved data pointers for cmd to point to the
459  * start of the buffer.
460  *
461  * Inputs : cmd - struct scsi_cmnd structure to have pointers reset.
462  */
463 
464 static __inline__ void initialize_SCp(struct scsi_cmnd *cmd)
465 {
466  /*
467  * Initialize the Scsi Pointer field so that all of the commands in the
468  * various queues are valid.
469  */
470 
471  if (scsi_bufflen(cmd)) {
472  cmd->SCp.buffer = scsi_sglist(cmd);
473  cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
474  cmd->SCp.ptr = (char *) SGADDR(cmd->SCp.buffer);
475  cmd->SCp.this_residual = cmd->SCp.buffer->length;
476  } else {
477  cmd->SCp.buffer = NULL;
478  cmd->SCp.buffers_residual = 0;
479  cmd->SCp.ptr = NULL;
480  cmd->SCp.this_residual = 0;
481  }
482 
483 }
484 
485 #include <linux/delay.h>
486 
487 #if 1
488 static struct {
489  unsigned char mask;
490  const char * name;}
491 signals[] = {{ SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" },
492  { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" },
493  { SR_SEL, "SEL" }, {0, NULL}},
494 basrs[] = {{BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}},
495 icrs[] = {{ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"},
496  {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"},
497  {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"},
498  {0, NULL}},
499 mrs[] = {{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"},
500  {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR,
501  "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"},
502  {MR_MONITOR_BSY, "MODE MONITOR BSY"},
503  {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"},
504  {0, NULL}};
505 
506 /*
507  * Function : void NCR5380_print(struct Scsi_Host *instance)
508  *
509  * Purpose : print the SCSI bus signals for debugging purposes
510  *
511  * Input : instance - which NCR5380
512  */
513 
514 static void NCR5380_print(struct Scsi_Host *instance) {
515  unsigned char status, data, basr, mr, icr, i;
516  unsigned long flags;
517 
518  local_irq_save(flags);
520  status = NCR5380_read(STATUS_REG);
521  mr = NCR5380_read(MODE_REG);
524  local_irq_restore(flags);
525  printk("STATUS_REG: %02x ", status);
526  for (i = 0; signals[i].mask ; ++i)
527  if (status & signals[i].mask)
528  printk(",%s", signals[i].name);
529  printk("\nBASR: %02x ", basr);
530  for (i = 0; basrs[i].mask ; ++i)
531  if (basr & basrs[i].mask)
532  printk(",%s", basrs[i].name);
533  printk("\nICR: %02x ", icr);
534  for (i = 0; icrs[i].mask; ++i)
535  if (icr & icrs[i].mask)
536  printk(",%s", icrs[i].name);
537  printk("\nMODE: %02x ", mr);
538  for (i = 0; mrs[i].mask; ++i)
539  if (mr & mrs[i].mask)
540  printk(",%s", mrs[i].name);
541  printk("\n");
542 }
543 
544 static struct {
545  unsigned char value;
546  const char *name;
547 } phases[] = {
548  {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
549  {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
550  {PHASE_UNKNOWN, "UNKNOWN"}};
551 
552 /*
553  * Function : void NCR5380_print_phase(struct Scsi_Host *instance)
554  *
555  * Purpose : print the current SCSI phase for debugging purposes
556  *
557  * Input : instance - which NCR5380
558  */
559 
560 static void NCR5380_print_phase(struct Scsi_Host *instance)
561 {
562  unsigned char status;
563  int i;
564 
565  status = NCR5380_read(STATUS_REG);
566  if (!(status & SR_REQ))
567  printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO);
568  else {
569  for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
570  (phases[i].value != (status & PHASE_MASK)); ++i);
571  printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name);
572  }
573 }
574 
575 #else /* !NDEBUG */
576 
577 /* dummies... */
578 __inline__ void NCR5380_print(struct Scsi_Host *instance) { };
579 __inline__ void NCR5380_print_phase(struct Scsi_Host *instance) { };
580 
581 #endif
582 
583 /*
584  * ++roman: New scheme of calling NCR5380_main()
585  *
586  * If we're not in an interrupt, we can call our main directly, it cannot be
587  * already running. Else, we queue it on a task queue, if not 'main_running'
588  * tells us that a lower level is already executing it. This way,
589  * 'main_running' needs not be protected in a special way.
590  *
591  * queue_main() is a utility function for putting our main onto the task
592  * queue, if main_running is false. It should be called only from a
593  * interrupt or bottom half.
594  */
595 
596 #include <linux/gfp.h>
597 #include <linux/workqueue.h>
598 #include <linux/interrupt.h>
599 
600 static volatile int main_running = 0;
601 static DECLARE_WORK(NCR5380_tqueue, NCR5380_main);
602 
603 static __inline__ void queue_main(void)
604 {
605  if (!main_running) {
606  /* If in interrupt and NCR5380_main() not already running,
607  queue it on the 'immediate' task queue, to be processed
608  immediately after the current interrupt processing has
609  finished. */
610  schedule_work(&NCR5380_tqueue);
611  }
612  /* else: nothing to do: the running NCR5380_main() will pick up
613  any newly queued command. */
614 }
615 
616 
617 static inline void NCR5380_all_init (void)
618 {
619  static int done = 0;
620  if (!done) {
621  INI_PRINTK("scsi : NCR5380_all_init()\n");
622  done = 1;
623  }
624 }
625 
626 
627 /*
628  * Function : void NCR58380_print_options (struct Scsi_Host *instance)
629  *
630  * Purpose : called by probe code indicating the NCR5380 driver
631  * options that were selected.
632  *
633  * Inputs : instance, pointer to this instance. Unused.
634  */
635 
636 static void __init NCR5380_print_options (struct Scsi_Host *instance)
637 {
638  printk(" generic options"
639 #ifdef AUTOSENSE
640  " AUTOSENSE"
641 #endif
642 #ifdef REAL_DMA
643  " REAL DMA"
644 #endif
645 #ifdef PARITY
646  " PARITY"
647 #endif
648 #ifdef SUPPORT_TAGS
649  " SCSI-2 TAGGED QUEUING"
650 #endif
651  );
652  printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
653 }
654 
655 /*
656  * Function : void NCR5380_print_status (struct Scsi_Host *instance)
657  *
658  * Purpose : print commands in the various queues, called from
659  * NCR5380_abort and NCR5380_debug to aid debugging.
660  *
661  * Inputs : instance, pointer to this instance.
662  */
663 
664 static void NCR5380_print_status (struct Scsi_Host *instance)
665 {
666  char *pr_bfr;
667  char *start;
668  int len;
669 
672 
673  pr_bfr = (char *) __get_free_page(GFP_ATOMIC);
674  if (!pr_bfr) {
675  printk("NCR5380_print_status: no memory for print buffer\n");
676  return;
677  }
678  len = NCR5380_proc_info(instance, pr_bfr, &start, 0, PAGE_SIZE, 0);
679  pr_bfr[len] = 0;
680  printk("\n%s\n", pr_bfr);
681  free_page((unsigned long) pr_bfr);
682 }
683 
684 
685 /******************************************/
686 /*
687  * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
688  *
689  * *buffer: I/O buffer
690  * **start: if inout == FALSE pointer into buffer where user read should start
691  * offset: current offset
692  * length: length of buffer
693  * hostno: Scsi_Host host_no
694  * inout: TRUE - user is writing; FALSE - user is reading
695  *
696  * Return the number of bytes read from or written
697 */
698 
699 #undef SPRINTF
700 #define SPRINTF(fmt,args...) \
701  do { if (pos + strlen(fmt) + 20 /* slop */ < buffer + length) \
702  pos += sprintf(pos, fmt , ## args); } while(0)
703 static
704 char *lprint_Scsi_Cmnd(struct scsi_cmnd *cmd, char *pos, char *buffer,
705  int length);
706 
707 static int NCR5380_proc_info(struct Scsi_Host *instance, char *buffer,
708  char **start, off_t offset, int length, int inout)
709 {
710  char *pos = buffer;
711  struct NCR5380_hostdata *hostdata;
712  struct scsi_cmnd *ptr;
713  unsigned long flags;
714  off_t begin = 0;
715 #define check_offset() \
716  do { \
717  if (pos - buffer < offset - begin) { \
718  begin += pos - buffer; \
719  pos = buffer; \
720  } \
721  } while (0)
722 
723  hostdata = (struct NCR5380_hostdata *)instance->hostdata;
724 
725  if (inout) { /* Has data been written to the file ? */
726  return(-ENOSYS); /* Currently this is a no-op */
727  }
728  SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
729  check_offset();
730  local_irq_save(flags);
731  SPRINTF("NCR5380: coroutine is%s running.\n", main_running ? "" : "n't");
732  check_offset();
733  if (!hostdata->connected)
734  SPRINTF("scsi%d: no currently connected command\n", HOSTNO);
735  else
736  pos = lprint_Scsi_Cmnd ((struct scsi_cmnd *) hostdata->connected,
737  pos, buffer, length);
738  SPRINTF("scsi%d: issue_queue\n", HOSTNO);
739  check_offset();
740  for (ptr = (struct scsi_cmnd *) hostdata->issue_queue; ptr; ptr = NEXT(ptr))
741  {
742  pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
743  check_offset();
744  }
745 
746  SPRINTF("scsi%d: disconnected_queue\n", HOSTNO);
747  check_offset();
748  for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr;
749  ptr = NEXT(ptr)) {
750  pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
751  check_offset();
752  }
753 
754  local_irq_restore(flags);
755  *start = buffer + (offset - begin);
756  if (pos - buffer < offset - begin)
757  return 0;
758  else if (pos - buffer - (offset - begin) < length)
759  return pos - buffer - (offset - begin);
760  return length;
761 }
762 
763 static char *lprint_Scsi_Cmnd(struct scsi_cmnd *cmd, char *pos, char *buffer,
764  int length)
765 {
766  int i, s;
767  unsigned char *command;
768  SPRINTF("scsi%d: destination target %d, lun %d\n",
769  H_NO(cmd), cmd->device->id, cmd->device->lun);
770  SPRINTF(" command = ");
771  command = cmd->cmnd;
772  SPRINTF("%2d (0x%02x)", command[0], command[0]);
773  for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
774  SPRINTF(" %02x", command[i]);
775  SPRINTF("\n");
776  return pos;
777 }
778 
779 
780 /*
781  * Function : void NCR5380_init (struct Scsi_Host *instance)
782  *
783  * Purpose : initializes *instance and corresponding 5380 chip.
784  *
785  * Inputs : instance - instantiation of the 5380 driver.
786  *
787  * Notes : I assume that the host, hostno, and id bits have been
788  * set correctly. I don't care about the irq and other fields.
789  *
790  */
791 
792 static int __init NCR5380_init(struct Scsi_Host *instance, int flags)
793 {
794  int i;
795  SETUP_HOSTDATA(instance);
796 
797  NCR5380_all_init();
798 
799  hostdata->aborted = 0;
800  hostdata->id_mask = 1 << instance->this_id;
801  hostdata->id_higher_mask = 0;
802  for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
803  if (i > hostdata->id_mask)
804  hostdata->id_higher_mask |= i;
805  for (i = 0; i < 8; ++i)
806  hostdata->busy[i] = 0;
807 #ifdef SUPPORT_TAGS
808  init_tags();
809 #endif
810 #if defined (REAL_DMA)
811  hostdata->dma_len = 0;
812 #endif
813  hostdata->targets_present = 0;
814  hostdata->connected = NULL;
815  hostdata->issue_queue = NULL;
816  hostdata->disconnected_queue = NULL;
817  hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT;
818 
819  if (!the_template) {
820  the_template = instance->hostt;
821  first_instance = instance;
822  }
823 
824 
825 #ifndef AUTOSENSE
826  if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1))
827  printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n"
828  " without AUTOSENSE option, contingent allegiance conditions may\n"
829  " be incorrectly cleared.\n", HOSTNO);
830 #endif /* def AUTOSENSE */
831 
836 
837  return 0;
838 }
839 
840 static void NCR5380_exit(struct Scsi_Host *instance)
841 {
842  /* Empty, as we didn't schedule any delayed work */
843 }
844 
845 /*
846  * Function : int NCR5380_queue_command (struct scsi_cmnd *cmd,
847  * void (*done)(struct scsi_cmnd *))
848  *
849  * Purpose : enqueues a SCSI command
850  *
851  * Inputs : cmd - SCSI command, done - function called on completion, with
852  * a pointer to the command descriptor.
853  *
854  * Returns : 0
855  *
856  * Side effects :
857  * cmd is added to the per instance issue_queue, with minor
858  * twiddling done to the host specific fields of cmd. If the
859  * main coroutine is not running, it is restarted.
860  *
861  */
862 
863 /* Only make static if a wrapper function is used */
864 static int NCR5380_queue_command_lck(struct scsi_cmnd *cmd,
865  void (*done)(struct scsi_cmnd *))
866 {
867  SETUP_HOSTDATA(cmd->device->host);
868  struct scsi_cmnd *tmp;
869  unsigned long flags;
870 
871 #if (NDEBUG & NDEBUG_NO_WRITE)
872  switch (cmd->cmnd[0]) {
873  case WRITE_6:
874  case WRITE_10:
875  printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
876  H_NO(cmd));
877  cmd->result = (DID_ERROR << 16);
878  done(cmd);
879  return 0;
880  }
881 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
882 
883 
884 #ifdef NCR5380_STATS
885 # if 0
886  if (!hostdata->connected && !hostdata->issue_queue &&
887  !hostdata->disconnected_queue) {
888  hostdata->timebase = jiffies;
889  }
890 # endif
891 # ifdef NCR5380_STAT_LIMIT
892  if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT)
893 # endif
894  switch (cmd->cmnd[0])
895  {
896  case WRITE:
897  case WRITE_6:
898  case WRITE_10:
899  hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
900  hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);
901  hostdata->pendingw++;
902  break;
903  case READ:
904  case READ_6:
905  case READ_10:
906  hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
907  hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);
908  hostdata->pendingr++;
909  break;
910  }
911 #endif
912 
913  /*
914  * We use the host_scribble field as a pointer to the next command
915  * in a queue
916  */
917 
918  SET_NEXT(cmd, NULL);
919  cmd->scsi_done = done;
920 
921  cmd->result = 0;
922 
923 
924  /*
925  * Insert the cmd into the issue queue. Note that REQUEST SENSE
926  * commands are added to the head of the queue since any command will
927  * clear the contingent allegiance condition that exists and the
928  * sense data is only guaranteed to be valid while the condition exists.
929  */
930 
931  local_irq_save(flags);
932  /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
933  * Otherwise a running NCR5380_main may steal the lock.
934  * Lock before actually inserting due to fairness reasons explained in
935  * atari_scsi.c. If we insert first, then it's impossible for this driver
936  * to release the lock.
937  * Stop timer for this command while waiting for the lock, or timeouts
938  * may happen (and they really do), and it's no good if the command doesn't
939  * appear in any of the queues.
940  * ++roman: Just disabling the NCR interrupt isn't sufficient here,
941  * because also a timer int can trigger an abort or reset, which would
942  * alter queues and touch the lock.
943  */
944  if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
945  LIST(cmd, hostdata->issue_queue);
946  SET_NEXT(cmd, hostdata->issue_queue);
947  hostdata->issue_queue = cmd;
948  } else {
949  for (tmp = (struct scsi_cmnd *)hostdata->issue_queue;
950  NEXT(tmp); tmp = NEXT(tmp))
951  ;
952  LIST(cmd, tmp);
953  SET_NEXT(tmp, cmd);
954  }
955 
956  local_irq_restore(flags);
957 
958  QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd),
959  (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
960 
961  /* If queue_command() is called from an interrupt (real one or bottom
962  * half), we let queue_main() do the job of taking care about main. If it
963  * is already running, this is a no-op, else main will be queued.
964  *
965  * If we're not in an interrupt, we can call NCR5380_main()
966  * unconditionally, because it cannot be already running.
967  */
968  if (in_interrupt() || ((flags >> 8) & 7) >= 6)
969  queue_main();
970  else
971  NCR5380_main(NULL);
972  return 0;
973 }
974 
976 
977 /*
978  * Function : NCR5380_main (void)
979  *
980  * Purpose : NCR5380_main is a coroutine that runs as long as more work can
981  * be done on the NCR5380 host adapters in a system. Both
982  * NCR5380_queue_command() and NCR5380_intr() will try to start it
983  * in case it is not running.
984  *
985  * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
986  * reenable them. This prevents reentrancy and kernel stack overflow.
987  */
988 
989 static void NCR5380_main (struct work_struct *bl)
990 {
991  struct scsi_cmnd *tmp, *prev;
992  struct Scsi_Host *instance = first_instance;
993  struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
994  int done;
995  unsigned long flags;
996 
997  /*
998  * We run (with interrupts disabled) until we're sure that none of
999  * the host adapters have anything that can be done, at which point
1000  * we set main_running to 0 and exit.
1001  *
1002  * Interrupts are enabled before doing various other internal
1003  * instructions, after we've decided that we need to run through
1004  * the loop again.
1005  *
1006  * this should prevent any race conditions.
1007  *
1008  * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1009  * because also a timer int can trigger an abort or reset, which can
1010  * alter queues and touch the Falcon lock.
1011  */
1012 
1013  /* Tell int handlers main() is now already executing. Note that
1014  no races are possible here. If an int comes in before
1015  'main_running' is set here, and queues/executes main via the
1016  task queue, it doesn't do any harm, just this instance of main
1017  won't find any work left to do. */
1018  if (main_running)
1019  return;
1020  main_running = 1;
1021 
1022  local_save_flags(flags);
1023  do {
1024  local_irq_disable(); /* Freeze request queues */
1025  done = 1;
1026 
1027  if (!hostdata->connected) {
1028  MAIN_PRINTK( "scsi%d: not connected\n", HOSTNO );
1029  /*
1030  * Search through the issue_queue for a command destined
1031  * for a target that's not busy.
1032  */
1033 #if (NDEBUG & NDEBUG_LISTS)
1034  for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, prev = NULL;
1035  tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
1036  ;
1037  if ((tmp == prev) && tmp) printk(" LOOP\n");/* else printk("\n");*/
1038 #endif
1039  for (tmp = (struct scsi_cmnd *) hostdata->issue_queue,
1040  prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp) ) {
1041 
1042 #if (NDEBUG & NDEBUG_LISTS)
1043  if (prev != tmp)
1044  printk("MAIN tmp=%p target=%d busy=%d lun=%d\n",
1045  tmp, tmp->target, hostdata->busy[tmp->target],
1046  tmp->lun);
1047 #endif
1048  /* When we find one, remove it from the issue queue. */
1049  /* ++guenther: possible race with Falcon locking */
1050  if (
1051 #ifdef SUPPORT_TAGS
1052  !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
1053 #else
1054  !(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))
1055 #endif
1056  ) {
1057  /* ++guenther: just to be sure, this must be atomic */
1059  if (prev) {
1060  REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1061  SET_NEXT(prev, NEXT(tmp));
1062  } else {
1063  REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
1064  hostdata->issue_queue = NEXT(tmp);
1065  }
1066  SET_NEXT(tmp, NULL);
1067 
1068  /* reenable interrupts after finding one */
1069  local_irq_restore(flags);
1070 
1071  /*
1072  * Attempt to establish an I_T_L nexus here.
1073  * On success, instance->hostdata->connected is set.
1074  * On failure, we must add the command back to the
1075  * issue queue so we can keep trying.
1076  */
1077  MAIN_PRINTK("scsi%d: main(): command for target %d "
1078  "lun %d removed from issue_queue\n",
1079  HOSTNO, tmp->target, tmp->lun);
1080  /*
1081  * REQUEST SENSE commands are issued without tagged
1082  * queueing, even on SCSI-II devices because the
1083  * contingent allegiance condition exists for the
1084  * entire unit.
1085  */
1086  /* ++roman: ...and the standard also requires that
1087  * REQUEST SENSE command are untagged.
1088  */
1089 
1090 #ifdef SUPPORT_TAGS
1091  cmd_get_tag( tmp, tmp->cmnd[0] != REQUEST_SENSE );
1092 #endif
1093  if (!NCR5380_select(instance, tmp,
1094  (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE :
1095  TAG_NEXT)) {
1096  break;
1097  } else {
1099  LIST(tmp, hostdata->issue_queue);
1100  SET_NEXT(tmp, hostdata->issue_queue);
1101  hostdata->issue_queue = tmp;
1102 #ifdef SUPPORT_TAGS
1103  cmd_free_tag( tmp );
1104 #endif
1105  local_irq_restore(flags);
1106  MAIN_PRINTK("scsi%d: main(): select() failed, "
1107  "returned to issue_queue\n", HOSTNO);
1108  if (hostdata->connected)
1109  break;
1110  }
1111  } /* if target/lun/target queue is not busy */
1112  } /* for issue_queue */
1113  } /* if (!hostdata->connected) */
1114  if (hostdata->connected
1115 #ifdef REAL_DMA
1116  && !hostdata->dma_len
1117 #endif
1118  ) {
1119  local_irq_restore(flags);
1120  MAIN_PRINTK("scsi%d: main: performing information transfer\n",
1121  HOSTNO);
1122  NCR5380_information_transfer(instance);
1123  MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO);
1124  done = 0;
1125  }
1126  } while (!done);
1127 
1128  /* Better allow ints _after_ 'main_running' has been cleared, else
1129  an interrupt could believe we'll pick up the work it left for
1130  us, but we won't see it anymore here... */
1131  main_running = 0;
1132  local_irq_restore(flags);
1133 }
1134 
1135 
1136 #ifdef REAL_DMA
1137 /*
1138  * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1139  *
1140  * Purpose : Called by interrupt handler when DMA finishes or a phase
1141  * mismatch occurs (which would finish the DMA transfer).
1142  *
1143  * Inputs : instance - this instance of the NCR5380.
1144  *
1145  */
1146 
1147 static void NCR5380_dma_complete( struct Scsi_Host *instance )
1148 {
1149  SETUP_HOSTDATA(instance);
1150  int transfered;
1151  unsigned char **data;
1152  volatile int *count;
1153 
1154  if (!hostdata->connected) {
1155  printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
1156  "no connected cmd\n", HOSTNO);
1157  return;
1158  }
1159 
1160  DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1163 
1164  if((sun3scsi_dma_finish(rq_data_dir(hostdata->connected->request)))) {
1165  printk("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n", HOSTNO);
1166  printk("please e-mail [email protected] with a description of how this\n");
1167  printk("error was produced.\n");
1168  BUG();
1169  }
1170 
1171  /* make sure we're not stuck in a data phase */
1173  BASR_ACK)) ==
1174  (BASR_PHASE_MATCH | BASR_ACK)) {
1175  printk("scsi%d: BASR %02x\n", HOSTNO, NCR5380_read(BUS_AND_STATUS_REG));
1176  printk("scsi%d: bus stuck in data phase -- probably a single byte "
1177  "overrun!\n", HOSTNO);
1178  printk("not prepared for this error!\n");
1179  printk("please e-mail [email protected] with a description of how this\n");
1180  printk("error was produced.\n");
1181  BUG();
1182  }
1183 
1184 
1185 
1189 
1190  transfered = hostdata->dma_len - NCR5380_dma_residual(instance);
1191  hostdata->dma_len = 0;
1192 
1193  data = (unsigned char **) &(hostdata->connected->SCp.ptr);
1194  count = &(hostdata->connected->SCp.this_residual);
1195  *data += transfered;
1196  *count -= transfered;
1197 
1198 }
1199 #endif /* REAL_DMA */
1200 
1201 
1202 /*
1203  * Function : void NCR5380_intr (int irq)
1204  *
1205  * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1206  * from the disconnected queue, and restarting NCR5380_main()
1207  * as required.
1208  *
1209  * Inputs : int irq, irq that caused this interrupt.
1210  *
1211  */
1212 
1213 static irqreturn_t NCR5380_intr (int irq, void *dev_id)
1214 {
1215  struct Scsi_Host *instance = first_instance;
1216  int done = 1, handled = 0;
1217  unsigned char basr;
1218 
1219  INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO);
1220 
1221  /* Look for pending interrupts */
1223  INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr);
1224  /* dispatch to appropriate routine if found and done=0 */
1225  if (basr & BASR_IRQ) {
1227  if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
1228  done = 0;
1229 // ENABLE_IRQ();
1230  INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO);
1231  NCR5380_reselect(instance);
1233  }
1234  else if (basr & BASR_PARITY_ERROR) {
1235  INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO);
1237  }
1238  else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1239  INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO);
1241  }
1242  else {
1243  /*
1244  * The rest of the interrupt conditions can occur only during a
1245  * DMA transfer
1246  */
1247 
1248 #if defined(REAL_DMA)
1249  /*
1250  * We should only get PHASE MISMATCH and EOP interrupts if we have
1251  * DMA enabled, so do a sanity check based on the current setting
1252  * of the MODE register.
1253  */
1254 
1255  if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
1256  ((basr & BASR_END_DMA_TRANSFER) ||
1257  !(basr & BASR_PHASE_MATCH))) {
1258 
1259  INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1260  NCR5380_dma_complete( instance );
1261  done = 0;
1262 // ENABLE_IRQ();
1263  } else
1264 #endif /* REAL_DMA */
1265  {
1266 /* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1267  if (basr & BASR_PHASE_MATCH)
1268  INT_PRINTK("scsi%d: unknown interrupt, "
1269  "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1270  HOSTNO, basr, NCR5380_read(MODE_REG),
1273 #ifdef SUN3_SCSI_VME
1274  dregs->csr |= CSR_DMA_ENABLE;
1275 #endif
1276  }
1277  } /* if !(SELECTION || PARITY) */
1278  handled = 1;
1279  } /* BASR & IRQ */
1280  else {
1281 
1282  printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
1283  "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
1286 #ifdef SUN3_SCSI_VME
1287  dregs->csr |= CSR_DMA_ENABLE;
1288 #endif
1289  }
1290 
1291  if (!done) {
1292  INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO);
1293  /* Put a call to NCR5380_main() on the queue... */
1294  queue_main();
1295  }
1296  return IRQ_RETVAL(handled);
1297 }
1298 
1299 #ifdef NCR5380_STATS
1300 static void collect_stats(struct NCR5380_hostdata *hostdata,
1301  struct scsi_cmnd *cmd)
1302 {
1303 # ifdef NCR5380_STAT_LIMIT
1304  if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT)
1305 # endif
1306  switch (cmd->cmnd[0])
1307  {
1308  case WRITE:
1309  case WRITE_6:
1310  case WRITE_10:
1311  hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase);
1312  /*hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);*/
1313  hostdata->pendingw--;
1314  break;
1315  case READ:
1316  case READ_6:
1317  case READ_10:
1318  hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase);
1319  /*hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);*/
1320  hostdata->pendingr--;
1321  break;
1322  }
1323 }
1324 #endif
1325 
1326 /*
1327  * Function : int NCR5380_select(struct Scsi_Host *instance,
1328  * struct scsi_cmnd *cmd, int tag);
1329  *
1330  * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1331  * including ARBITRATION, SELECTION, and initial message out for
1332  * IDENTIFY and queue messages.
1333  *
1334  * Inputs : instance - instantiation of the 5380 driver on which this
1335  * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1336  * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1337  * the command that is presently connected.
1338  *
1339  * Returns : -1 if selection could not execute for some reason,
1340  * 0 if selection succeeded or failed because the target
1341  * did not respond.
1342  *
1343  * Side effects :
1344  * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1345  * with registers as they should have been on entry - ie
1346  * SELECT_ENABLE will be set appropriately, the NCR5380
1347  * will cease to drive any SCSI bus signals.
1348  *
1349  * If successful : I_T_L or I_T_L_Q nexus will be established,
1350  * instance->connected will be set to cmd.
1351  * SELECT interrupt will be disabled.
1352  *
1353  * If failed (no target) : cmd->scsi_done() will be called, and the
1354  * cmd->result host byte set to DID_BAD_TARGET.
1355  */
1356 
1357 static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd,
1358  int tag)
1359 {
1360  SETUP_HOSTDATA(instance);
1361  unsigned char tmp[3], phase;
1362  unsigned char *data;
1363  int len;
1364  unsigned long timeout;
1365  unsigned long flags;
1366 
1367  hostdata->restart_select = 0;
1369  ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO,
1370  instance->this_id);
1371 
1372  /*
1373  * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1374  * data bus during SELECTION.
1375  */
1376 
1377  local_irq_save(flags);
1378  if (hostdata->connected) {
1379  local_irq_restore(flags);
1380  return -1;
1381  }
1383 
1384 
1385  /*
1386  * Start arbitration.
1387  */
1388 
1391 
1392  local_irq_restore(flags);
1393 
1394  /* Wait for arbitration logic to complete */
1395 #ifdef NCR_TIMEOUT
1396  {
1397  unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
1398 
1400  && time_before(jiffies, timeout) && !hostdata->connected)
1401  ;
1402  if (time_after_eq(jiffies, timeout))
1403  {
1404  printk("scsi : arbitration timeout at %d\n", __LINE__);
1407  return -1;
1408  }
1409  }
1410 #else /* NCR_TIMEOUT */
1411  while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)
1412  && !hostdata->connected);
1413 #endif
1414 
1415  ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO);
1416 
1417  if (hostdata->connected) {
1419  return -1;
1420  }
1421  /*
1422  * The arbitration delay is 2.2us, but this is a minimum and there is
1423  * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1424  * the integral nature of udelay().
1425  *
1426  */
1427 
1428  udelay(3);
1429 
1430  /* Check for lost arbitration */
1433  (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1434  hostdata->connected) {
1436  ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1437  HOSTNO);
1438  return -1;
1439  }
1440 
1441  /* after/during arbitration, BSY should be asserted.
1442  IBM DPES-31080 Version S31Q works now */
1443  /* Tnx to [email protected] for finding this! (Roman) */
1445  ICR_ASSERT_BSY ) ;
1446 
1447  if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1448  hostdata->connected) {
1451  ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1452  HOSTNO);
1453  return -1;
1454  }
1455 
1456  /*
1457  * Again, bus clear + bus settle time is 1.2us, however, this is
1458  * a minimum so we'll udelay ceil(1.2)
1459  */
1460 
1461 #ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1462  /* ++roman: But some targets (see above :-) seem to need a bit more... */
1463  udelay(15);
1464 #else
1465  udelay(2);
1466 #endif
1467 
1468  if (hostdata->connected) {
1471  return -1;
1472  }
1473 
1474  ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO);
1475 
1476  /*
1477  * Now that we have won arbitration, start Selection process, asserting
1478  * the host and target ID's on the SCSI bus.
1479  */
1480 
1481  NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id)));
1482 
1483  /*
1484  * Raise ATN while SEL is true before BSY goes false from arbitration,
1485  * since this is the only way to guarantee that we'll get a MESSAGE OUT
1486  * phase immediately after selection.
1487  */
1488 
1492 
1493  /*
1494  * Reselect interrupts must be turned off prior to the dropping of BSY,
1495  * otherwise we will trigger an interrupt.
1496  */
1497 
1498  if (hostdata->connected) {
1500  return -1;
1501  }
1502 
1504 
1505  /*
1506  * The initiator shall then wait at least two deskew delays and release
1507  * the BSY signal.
1508  */
1509  udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1510 
1511  /* Reset BSY */
1514 
1515  /*
1516  * Something weird happens when we cease to drive BSY - looks
1517  * like the board/chip is letting us do another read before the
1518  * appropriate propagation delay has expired, and we're confusing
1519  * a BSY signal from ourselves as the target's response to SELECTION.
1520  *
1521  * A small delay (the 'C++' frontend breaks the pipeline with an
1522  * unnecessary jump, making it work on my 386-33/Trantor T128, the
1523  * tighter 'C' code breaks and requires this) solves the problem -
1524  * the 1 us delay is arbitrary, and only used because this delay will
1525  * be the same on other platforms and since it works here, it should
1526  * work there.
1527  *
1528  * wingel suggests that this could be due to failing to wait
1529  * one deskew delay.
1530  */
1531 
1532  udelay(1);
1533 
1534  SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
1535 
1536  /*
1537  * The SCSI specification calls for a 250 ms timeout for the actual
1538  * selection.
1539  */
1540 
1541  timeout = jiffies + 25;
1542 
1543  /*
1544  * XXX very interesting - we're seeing a bounce where the BSY we
1545  * asserted is being reflected / still asserted (propagation delay?)
1546  * and it's detecting as true. Sigh.
1547  */
1548 
1549 #if 0
1550  /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1551  * IO while SEL is true. But again, there are some disks out the in the
1552  * world that do that nevertheless. (Somebody claimed that this announces
1553  * reselection capability of the target.) So we better skip that test and
1554  * only wait for BSY... (Famous german words: Der Kl├╝gere gibt nach :-)
1555  */
1556 
1557  while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) &
1558  (SR_BSY | SR_IO)));
1559 
1560  if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) ==
1561  (SR_SEL | SR_IO)) {
1563  NCR5380_reselect(instance);
1564  printk (KERN_ERR "scsi%d: reselection after won arbitration?\n",
1565  HOSTNO);
1567  return -1;
1568  }
1569 #else
1570  while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY));
1571 #endif
1572 
1573  /*
1574  * No less than two deskew delays after the initiator detects the
1575  * BSY signal is true, it shall release the SEL signal and may
1576  * change the DATA BUS. -wingel
1577  */
1578 
1579  udelay(1);
1580 
1582 
1583  if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1585  if (hostdata->targets_present & (1 << cmd->device->id)) {
1586  printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO);
1587  if (hostdata->restart_select)
1588  printk(KERN_NOTICE "\trestart select\n");
1591  return -1;
1592  }
1593  cmd->result = DID_BAD_TARGET << 16;
1594 #ifdef NCR5380_STATS
1595  collect_stats(hostdata, cmd);
1596 #endif
1597 #ifdef SUPPORT_TAGS
1598  cmd_free_tag( cmd );
1599 #endif
1600  cmd->scsi_done(cmd);
1602  SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO);
1604  return 0;
1605  }
1606 
1607  hostdata->targets_present |= (1 << cmd->device->id);
1608 
1609  /*
1610  * Since we followed the SCSI spec, and raised ATN while SEL
1611  * was true but before BSY was false during selection, the information
1612  * transfer phase should be a MESSAGE OUT phase so that we can send the
1613  * IDENTIFY message.
1614  *
1615  * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1616  * message (2 bytes) with a tag ID that we increment with every command
1617  * until it wraps back to 0.
1618  *
1619  * XXX - it turns out that there are some broken SCSI-II devices,
1620  * which claim to support tagged queuing but fail when more than
1621  * some number of commands are issued at once.
1622  */
1623 
1624  /* Wait for start of REQ/ACK handshake */
1625  while (!(NCR5380_read(STATUS_REG) & SR_REQ));
1626 
1627  SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1628  HOSTNO, cmd->device->id);
1629  tmp[0] = IDENTIFY(1, cmd->device->lun);
1630 
1631 #ifdef SUPPORT_TAGS
1632  if (cmd->tag != TAG_NONE) {
1633  tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
1634  tmp[2] = cmd->tag;
1635  len = 3;
1636  } else
1637  len = 1;
1638 #else
1639  len = 1;
1640  cmd->tag=0;
1641 #endif /* SUPPORT_TAGS */
1642 
1643  /* Send message(s) */
1644  data = tmp;
1645  phase = PHASE_MSGOUT;
1646  NCR5380_transfer_pio(instance, &phase, &len, &data);
1647  SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO);
1648  /* XXX need to handle errors here */
1649  hostdata->connected = cmd;
1650 #ifndef SUPPORT_TAGS
1651  hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1652 #endif
1653 #ifdef SUN3_SCSI_VME
1654  dregs->csr |= CSR_INTR;
1655 #endif
1656  initialize_SCp(cmd);
1657 
1658 
1659  return 0;
1660 }
1661 
1662 /*
1663  * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1664  * unsigned char *phase, int *count, unsigned char **data)
1665  *
1666  * Purpose : transfers data in given phase using polled I/O
1667  *
1668  * Inputs : instance - instance of driver, *phase - pointer to
1669  * what phase is expected, *count - pointer to number of
1670  * bytes to transfer, **data - pointer to data pointer.
1671  *
1672  * Returns : -1 when different phase is entered without transferring
1673  * maximum number of bytes, 0 if all bytes are transferred or exit
1674  * is in same phase.
1675  *
1676  * Also, *phase, *count, *data are modified in place.
1677  *
1678  * XXX Note : handling for bus free may be useful.
1679  */
1680 
1681 /*
1682  * Note : this code is not as quick as it could be, however it
1683  * IS 100% reliable, and for the actual data transfer where speed
1684  * counts, we will always do a pseudo DMA or DMA transfer.
1685  */
1686 
1687 static int NCR5380_transfer_pio( struct Scsi_Host *instance,
1688  unsigned char *phase, int *count,
1689  unsigned char **data)
1690 {
1691  register unsigned char p = *phase, tmp;
1692  register int c = *count;
1693  register unsigned char *d = *data;
1694 
1695  /*
1696  * The NCR5380 chip will only drive the SCSI bus when the
1697  * phase specified in the appropriate bits of the TARGET COMMAND
1698  * REGISTER match the STATUS REGISTER
1699  */
1700 
1702 
1703  do {
1704  /*
1705  * Wait for assertion of REQ, after which the phase bits will be
1706  * valid
1707  */
1708  while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ));
1709 
1710  HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO);
1711 
1712  /* Check for phase mismatch */
1713  if ((tmp & PHASE_MASK) != p) {
1714  PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO);
1716  break;
1717  }
1718 
1719  /* Do actual transfer from SCSI bus to / from memory */
1720  if (!(p & SR_IO))
1722  else
1724 
1725  ++d;
1726 
1727  /*
1728  * The SCSI standard suggests that in MSGOUT phase, the initiator
1729  * should drop ATN on the last byte of the message phase
1730  * after REQ has been asserted for the handshake but before
1731  * the initiator raises ACK.
1732  */
1733 
1734  if (!(p & SR_IO)) {
1735  if (!((p & SR_MSG) && c > 1)) {
1737  ICR_ASSERT_DATA);
1741  } else {
1747  }
1748  } else {
1751  }
1752 
1753  while (NCR5380_read(STATUS_REG) & SR_REQ);
1754 
1755  HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO);
1756 
1757 /*
1758  * We have several special cases to consider during REQ/ACK handshaking :
1759  * 1. We were in MSGOUT phase, and we are on the last byte of the
1760  * message. ATN must be dropped as ACK is dropped.
1761  *
1762  * 2. We are in a MSGIN phase, and we are on the last byte of the
1763  * message. We must exit with ACK asserted, so that the calling
1764  * code may raise ATN before dropping ACK to reject the message.
1765  *
1766  * 3. ACK and ATN are clear and the target may proceed as normal.
1767  */
1768  if (!(p == PHASE_MSGIN && c == 1)) {
1769  if (p == PHASE_MSGOUT && c > 1)
1771  else
1773  }
1774  } while (--c);
1775 
1776  PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c);
1777 
1778  *count = c;
1779  *data = d;
1780  tmp = NCR5380_read(STATUS_REG);
1781  /* The phase read from the bus is valid if either REQ is (already)
1782  * asserted or if ACK hasn't been released yet. The latter is the case if
1783  * we're in MSGIN and all wanted bytes have been received. */
1784  if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
1785  *phase = tmp & PHASE_MASK;
1786  else
1787  *phase = PHASE_UNKNOWN;
1788 
1789  if (!c || (*phase == p))
1790  return 0;
1791  else
1792  return -1;
1793 }
1794 
1795 /*
1796  * Function : do_abort (Scsi_Host *host)
1797  *
1798  * Purpose : abort the currently established nexus. Should only be
1799  * called from a routine which can drop into a
1800  *
1801  * Returns : 0 on success, -1 on failure.
1802  */
1803 
1804 static int do_abort (struct Scsi_Host *host)
1805 {
1806  unsigned char tmp, *msgptr, phase;
1807  int len;
1808 
1809  /* Request message out phase */
1811 
1812  /*
1813  * Wait for the target to indicate a valid phase by asserting
1814  * REQ. Once this happens, we'll have either a MSGOUT phase
1815  * and can immediately send the ABORT message, or we'll have some
1816  * other phase and will have to source/sink data.
1817  *
1818  * We really don't care what value was on the bus or what value
1819  * the target sees, so we just handshake.
1820  */
1821 
1822  while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ));
1823 
1825 
1826  if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1828  ICR_ASSERT_ACK);
1829  while (NCR5380_read(STATUS_REG) & SR_REQ);
1831  }
1832 
1833  tmp = ABORT;
1834  msgptr = &tmp;
1835  len = 1;
1836  phase = PHASE_MSGOUT;
1837  NCR5380_transfer_pio (host, &phase, &len, &msgptr);
1838 
1839  /*
1840  * If we got here, and the command completed successfully,
1841  * we're about to go into bus free state.
1842  */
1843 
1844  return len ? -1 : 0;
1845 }
1846 
1847 #if defined(REAL_DMA)
1848 /*
1849  * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1850  * unsigned char *phase, int *count, unsigned char **data)
1851  *
1852  * Purpose : transfers data in given phase using either real
1853  * or pseudo DMA.
1854  *
1855  * Inputs : instance - instance of driver, *phase - pointer to
1856  * what phase is expected, *count - pointer to number of
1857  * bytes to transfer, **data - pointer to data pointer.
1858  *
1859  * Returns : -1 when different phase is entered without transferring
1860  * maximum number of bytes, 0 if all bytes or transferred or exit
1861  * is in same phase.
1862  *
1863  * Also, *phase, *count, *data are modified in place.
1864  *
1865  */
1866 
1867 
1868 static int NCR5380_transfer_dma( struct Scsi_Host *instance,
1869  unsigned char *phase, int *count,
1870  unsigned char **data)
1871 {
1872  SETUP_HOSTDATA(instance);
1873  register int c = *count;
1874  register unsigned char p = *phase;
1875  unsigned long flags;
1876 
1877  /* sanity check */
1878  if(!sun3_dma_setup_done) {
1879  printk("scsi%d: transfer_dma without setup!\n", HOSTNO);
1880  BUG();
1881  }
1882  hostdata->dma_len = c;
1883 
1884  DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1885  HOSTNO, (p & SR_IO) ? "reading" : "writing",
1886  c, (p & SR_IO) ? "to" : "from", *data);
1887 
1888  /* netbsd turns off ints here, why not be safe and do it too */
1889  local_irq_save(flags);
1890 
1891  /* send start chain */
1892  sun3scsi_dma_start(c, *data);
1893 
1894  if (p & SR_IO) {
1900  } else {
1906  }
1907 
1908 #ifdef SUN3_SCSI_VME
1909  dregs->csr |= CSR_DMA_ENABLE;
1910 #endif
1911 
1912  local_irq_restore(flags);
1913 
1914  sun3_dma_active = 1;
1915  return 0;
1916 }
1917 #endif /* defined(REAL_DMA) */
1918 
1919 /*
1920  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1921  *
1922  * Purpose : run through the various SCSI phases and do as the target
1923  * directs us to. Operates on the currently connected command,
1924  * instance->connected.
1925  *
1926  * Inputs : instance, instance for which we are doing commands
1927  *
1928  * Side effects : SCSI things happen, the disconnected queue will be
1929  * modified if a command disconnects, *instance->connected will
1930  * change.
1931  *
1932  * XXX Note : we need to watch for bus free or a reset condition here
1933  * to recover from an unexpected bus free condition.
1934  */
1935 
1936 static void NCR5380_information_transfer (struct Scsi_Host *instance)
1937 {
1938  SETUP_HOSTDATA(instance);
1939  unsigned long flags;
1940  unsigned char msgout = NOP;
1941  int sink = 0;
1942  int len;
1943 #if defined(REAL_DMA)
1944  int transfersize;
1945 #endif
1946  unsigned char *data;
1947  unsigned char phase, tmp, extended_msg[10], old_phase=0xff;
1948  struct scsi_cmnd *cmd = (struct scsi_cmnd *) hostdata->connected;
1949 
1950 #ifdef SUN3_SCSI_VME
1951  dregs->csr |= CSR_INTR;
1952 #endif
1953 
1954  while (1) {
1955  tmp = NCR5380_read(STATUS_REG);
1956  /* We only have a valid SCSI phase when REQ is asserted */
1957  if (tmp & SR_REQ) {
1958  phase = (tmp & PHASE_MASK);
1959  if (phase != old_phase) {
1960  old_phase = phase;
1962  }
1963 
1964  if(phase == PHASE_CMDOUT) {
1965  void *d;
1966  unsigned long count;
1967 
1968  if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
1969  count = cmd->SCp.buffer->length;
1970  d = SGADDR(cmd->SCp.buffer);
1971  } else {
1972  count = cmd->SCp.this_residual;
1973  d = cmd->SCp.ptr;
1974  }
1975 #ifdef REAL_DMA
1976  /* this command setup for dma yet? */
1977  if((count > SUN3_DMA_MINSIZE) && (sun3_dma_setup_done
1978  != cmd))
1979  {
1980  if (cmd->request->cmd_type == REQ_TYPE_FS) {
1981  sun3scsi_dma_setup(d, count,
1982  rq_data_dir(cmd->request));
1983  sun3_dma_setup_done = cmd;
1984  }
1985  }
1986 #endif
1987 #ifdef SUN3_SCSI_VME
1988  dregs->csr |= CSR_INTR;
1989 #endif
1990  }
1991 
1992 
1993  if (sink && (phase != PHASE_MSGOUT)) {
1995 
1997  ICR_ASSERT_ACK);
1998  while (NCR5380_read(STATUS_REG) & SR_REQ);
2000  ICR_ASSERT_ATN);
2001  sink = 0;
2002  continue;
2003  }
2004 
2005  switch (phase) {
2006  case PHASE_DATAOUT:
2007 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2008  printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2009  "aborted\n", HOSTNO);
2010  sink = 1;
2011  do_abort(instance);
2012  cmd->result = DID_ERROR << 16;
2013  cmd->scsi_done(cmd);
2014  return;
2015 #endif
2016  case PHASE_DATAIN:
2017  /*
2018  * If there is no room left in the current buffer in the
2019  * scatter-gather list, move onto the next one.
2020  */
2021  if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2022  ++cmd->SCp.buffer;
2023  --cmd->SCp.buffers_residual;
2024  cmd->SCp.this_residual = cmd->SCp.buffer->length;
2025  cmd->SCp.ptr = SGADDR(cmd->SCp.buffer);
2026  INF_PRINTK("scsi%d: %d bytes and %d buffers left\n",
2027  HOSTNO, cmd->SCp.this_residual,
2028  cmd->SCp.buffers_residual);
2029  }
2030 
2031  /*
2032  * The preferred transfer method is going to be
2033  * PSEUDO-DMA for systems that are strictly PIO,
2034  * since we can let the hardware do the handshaking.
2035  *
2036  * For this to work, we need to know the transfersize
2037  * ahead of time, since the pseudo-DMA code will sit
2038  * in an unconditional loop.
2039  */
2040 
2041 /* ++roman: I suggest, this should be
2042  * #if def(REAL_DMA)
2043  * instead of leaving REAL_DMA out.
2044  */
2045 
2046 #if defined(REAL_DMA)
2047 // if (!cmd->device->borken &&
2048  if((transfersize =
2049  NCR5380_dma_xfer_len(instance,cmd,phase)) > SUN3_DMA_MINSIZE) {
2050  len = transfersize;
2051  cmd->SCp.phase = phase;
2052 
2053  if (NCR5380_transfer_dma(instance, &phase,
2054  &len, (unsigned char **) &cmd->SCp.ptr)) {
2055  /*
2056  * If the watchdog timer fires, all future
2057  * accesses to this device will use the
2058  * polled-IO. */
2059  printk(KERN_NOTICE "scsi%d: switching target %d "
2060  "lun %d to slow handshake\n", HOSTNO,
2061  cmd->device->id, cmd->device->lun);
2062  cmd->device->borken = 1;
2064  ICR_ASSERT_ATN);
2065  sink = 1;
2066  do_abort(instance);
2067  cmd->result = DID_ERROR << 16;
2068  cmd->scsi_done(cmd);
2069  /* XXX - need to source or sink data here, as appropriate */
2070  } else {
2071 #ifdef REAL_DMA
2072  /* ++roman: When using real DMA,
2073  * information_transfer() should return after
2074  * starting DMA since it has nothing more to
2075  * do.
2076  */
2077  return;
2078 #else
2079  cmd->SCp.this_residual -= transfersize - len;
2080 #endif
2081  }
2082  } else
2083 #endif /* defined(REAL_DMA) */
2084  NCR5380_transfer_pio(instance, &phase,
2085  (int *) &cmd->SCp.this_residual, (unsigned char **)
2086  &cmd->SCp.ptr);
2087 #ifdef REAL_DMA
2088  /* if we had intended to dma that command clear it */
2089  if(sun3_dma_setup_done == cmd)
2090  sun3_dma_setup_done = NULL;
2091 #endif
2092 
2093  break;
2094  case PHASE_MSGIN:
2095  len = 1;
2096  data = &tmp;
2097  NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */
2098  NCR5380_transfer_pio(instance, &phase, &len, &data);
2099  cmd->SCp.Message = tmp;
2100 
2101  switch (tmp) {
2102  /*
2103  * Linking lets us reduce the time required to get the
2104  * next command out to the device, hopefully this will
2105  * mean we don't waste another revolution due to the delays
2106  * required by ARBITRATION and another SELECTION.
2107  *
2108  * In the current implementation proposal, low level drivers
2109  * merely have to start the next command, pointed to by
2110  * next_link, done() is called as with unlinked commands.
2111  */
2112 #ifdef LINKED
2113  case LINKED_CMD_COMPLETE:
2115  /* Accept message by clearing ACK */
2117 
2118  LNK_PRINTK("scsi%d: target %d lun %d linked command "
2119  "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun);
2120 
2121  /* Enable reselect interrupts */
2123  /*
2124  * Sanity check : A linked command should only terminate
2125  * with one of these messages if there are more linked
2126  * commands available.
2127  */
2128 
2129  if (!cmd->next_link) {
2130  printk(KERN_NOTICE "scsi%d: target %d lun %d "
2131  "linked command complete, no next_link\n",
2132  HOSTNO, cmd->device->id, cmd->device->lun);
2133  sink = 1;
2134  do_abort (instance);
2135  return;
2136  }
2137 
2138  initialize_SCp(cmd->next_link);
2139  /* The next command is still part of this process; copy it
2140  * and don't free it! */
2141  cmd->next_link->tag = cmd->tag;
2142  cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2143  LNK_PRINTK("scsi%d: target %d lun %d linked request "
2144  "done, calling scsi_done().\n",
2145  HOSTNO, cmd->device->id, cmd->device->lun);
2146 #ifdef NCR5380_STATS
2147  collect_stats(hostdata, cmd);
2148 #endif
2149  cmd->scsi_done(cmd);
2150  cmd = hostdata->connected;
2151  break;
2152 #endif /* def LINKED */
2153  case ABORT:
2154  case COMMAND_COMPLETE:
2155  /* Accept message by clearing ACK */
2157  hostdata->connected = NULL;
2158  QU_PRINTK("scsi%d: command for target %d, lun %d "
2159  "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
2160 #ifdef SUPPORT_TAGS
2161  cmd_free_tag( cmd );
2162  if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
2163  /* Turn a QUEUE FULL status into BUSY, I think the
2164  * mid level cannot handle QUEUE FULL :-( (The
2165  * command is retried after BUSY). Also update our
2166  * queue size to the number of currently issued
2167  * commands now.
2168  */
2169  /* ++Andreas: the mid level code knows about
2170  QUEUE_FULL now. */
2171  TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
2172  TAG_PRINTK("scsi%d: target %d lun %d returned "
2173  "QUEUE_FULL after %d commands\n",
2174  HOSTNO, cmd->device->id, cmd->device->lun,
2175  ta->nr_allocated);
2176  if (ta->queue_size > ta->nr_allocated)
2177  ta->nr_allocated = ta->queue_size;
2178  }
2179 #else
2180  hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2181 #endif
2182  /* Enable reselect interrupts */
2184 
2185  /*
2186  * I'm not sure what the correct thing to do here is :
2187  *
2188  * If the command that just executed is NOT a request
2189  * sense, the obvious thing to do is to set the result
2190  * code to the values of the stored parameters.
2191  *
2192  * If it was a REQUEST SENSE command, we need some way to
2193  * differentiate between the failure code of the original
2194  * and the failure code of the REQUEST sense - the obvious
2195  * case is success, where we fall through and leave the
2196  * result code unchanged.
2197  *
2198  * The non-obvious place is where the REQUEST SENSE failed
2199  */
2200 
2201  if (cmd->cmnd[0] != REQUEST_SENSE)
2202  cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2203  else if (status_byte(cmd->SCp.Status) != GOOD)
2204  cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2205 
2206 #ifdef AUTOSENSE
2207  if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2208  hostdata->ses.cmd_len) {
2209  scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2210  hostdata->ses.cmd_len = 0 ;
2211  }
2212 
2213  if ((cmd->cmnd[0] != REQUEST_SENSE) &&
2214  (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2215  scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2216  ASEN_PRINTK("scsi%d: performing request sense\n",
2217  HOSTNO);
2218  /* this is initialized from initialize_SCp
2219  cmd->SCp.buffer = NULL;
2220  cmd->SCp.buffers_residual = 0;
2221  */
2222 
2223  local_irq_save(flags);
2224  LIST(cmd,hostdata->issue_queue);
2225  SET_NEXT(cmd, hostdata->issue_queue);
2226  hostdata->issue_queue = (struct scsi_cmnd *) cmd;
2227  local_irq_restore(flags);
2228  QU_PRINTK("scsi%d: REQUEST SENSE added to head of "
2229  "issue queue\n", H_NO(cmd));
2230  } else
2231 #endif /* def AUTOSENSE */
2232  {
2233 #ifdef NCR5380_STATS
2234  collect_stats(hostdata, cmd);
2235 #endif
2236  cmd->scsi_done(cmd);
2237  }
2238 
2240  /*
2241  * Restore phase bits to 0 so an interrupted selection,
2242  * arbitration can resume.
2243  */
2245 
2246  while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2247  barrier();
2248 
2249  return;
2250  case MESSAGE_REJECT:
2251  /* Accept message by clearing ACK */
2253  /* Enable reselect interrupts */
2255  switch (hostdata->last_message) {
2256  case HEAD_OF_QUEUE_TAG:
2257  case ORDERED_QUEUE_TAG:
2258  case SIMPLE_QUEUE_TAG:
2259  /* The target obviously doesn't support tagged
2260  * queuing, even though it announced this ability in
2261  * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2262  * clear 'tagged_supported' and lock the LUN, since
2263  * the command is treated as untagged further on.
2264  */
2265  cmd->device->tagged_supported = 0;
2266  hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2267  cmd->tag = TAG_NONE;
2268  TAG_PRINTK("scsi%d: target %d lun %d rejected "
2269  "QUEUE_TAG message; tagged queuing "
2270  "disabled\n",
2271  HOSTNO, cmd->device->id, cmd->device->lun);
2272  break;
2273  }
2274  break;
2275  case DISCONNECT:
2276  /* Accept message by clearing ACK */
2278  local_irq_save(flags);
2279  cmd->device->disconnect = 1;
2280  LIST(cmd,hostdata->disconnected_queue);
2281  SET_NEXT(cmd, hostdata->disconnected_queue);
2282  hostdata->connected = NULL;
2283  hostdata->disconnected_queue = cmd;
2284  local_irq_restore(flags);
2285  QU_PRINTK("scsi%d: command for target %d lun %d was "
2286  "moved from connected to the "
2287  "disconnected_queue\n", HOSTNO,
2288  cmd->device->id, cmd->device->lun);
2289  /*
2290  * Restore phase bits to 0 so an interrupted selection,
2291  * arbitration can resume.
2292  */
2294 
2295  /* Enable reselect interrupts */
2297  /* Wait for bus free to avoid nasty timeouts */
2298  while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2299  barrier();
2300 #ifdef SUN3_SCSI_VME
2301  dregs->csr |= CSR_DMA_ENABLE;
2302 #endif
2303  return;
2304  /*
2305  * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2306  * operation, in violation of the SCSI spec so we can safely
2307  * ignore SAVE/RESTORE pointers calls.
2308  *
2309  * Unfortunately, some disks violate the SCSI spec and
2310  * don't issue the required SAVE_POINTERS message before
2311  * disconnecting, and we have to break spec to remain
2312  * compatible.
2313  */
2314  case SAVE_POINTERS:
2315  case RESTORE_POINTERS:
2316  /* Accept message by clearing ACK */
2318  /* Enable reselect interrupts */
2320  break;
2321  case EXTENDED_MESSAGE:
2322 /*
2323  * Extended messages are sent in the following format :
2324  * Byte
2325  * 0 EXTENDED_MESSAGE == 1
2326  * 1 length (includes one byte for code, doesn't
2327  * include first two bytes)
2328  * 2 code
2329  * 3..length+1 arguments
2330  *
2331  * Start the extended message buffer with the EXTENDED_MESSAGE
2332  * byte, since spi_print_msg() wants the whole thing.
2333  */
2334  extended_msg[0] = EXTENDED_MESSAGE;
2335  /* Accept first byte by clearing ACK */
2337 
2338  EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO);
2339 
2340  len = 2;
2341  data = extended_msg + 1;
2342  phase = PHASE_MSGIN;
2343  NCR5380_transfer_pio(instance, &phase, &len, &data);
2344  EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2345  (int)extended_msg[1], (int)extended_msg[2]);
2346 
2347  if (!len && extended_msg[1] <=
2348  (sizeof (extended_msg) - 1)) {
2349  /* Accept third byte by clearing ACK */
2351  len = extended_msg[1] - 1;
2352  data = extended_msg + 3;
2353  phase = PHASE_MSGIN;
2354 
2355  NCR5380_transfer_pio(instance, &phase, &len, &data);
2356  EXT_PRINTK("scsi%d: message received, residual %d\n",
2357  HOSTNO, len);
2358 
2359  switch (extended_msg[2]) {
2360  case EXTENDED_SDTR:
2361  case EXTENDED_WDTR:
2364  tmp = 0;
2365  }
2366  } else if (len) {
2367  printk(KERN_NOTICE "scsi%d: error receiving "
2368  "extended message\n", HOSTNO);
2369  tmp = 0;
2370  } else {
2371  printk(KERN_NOTICE "scsi%d: extended message "
2372  "code %02x length %d is too long\n",
2373  HOSTNO, extended_msg[2], extended_msg[1]);
2374  tmp = 0;
2375  }
2376  /* Fall through to reject message */
2377 
2378  /*
2379  * If we get something weird that we aren't expecting,
2380  * reject it.
2381  */
2382  default:
2383  if (!tmp) {
2384  printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO);
2385  spi_print_msg(extended_msg);
2386  printk("\n");
2387  } else if (tmp != EXTENDED_MESSAGE)
2388  printk(KERN_DEBUG "scsi%d: rejecting unknown "
2389  "message %02x from target %d, lun %d\n",
2390  HOSTNO, tmp, cmd->device->id, cmd->device->lun);
2391  else
2392  printk(KERN_DEBUG "scsi%d: rejecting unknown "
2393  "extended message "
2394  "code %02x, length %d from target %d, lun %d\n",
2395  HOSTNO, extended_msg[1], extended_msg[0],
2396  cmd->device->id, cmd->device->lun);
2397 
2398 
2399  msgout = MESSAGE_REJECT;
2401  ICR_ASSERT_ATN);
2402  break;
2403  } /* switch (tmp) */
2404  break;
2405  case PHASE_MSGOUT:
2406  len = 1;
2407  data = &msgout;
2408  hostdata->last_message = msgout;
2409  NCR5380_transfer_pio(instance, &phase, &len, &data);
2410  if (msgout == ABORT) {
2411 #ifdef SUPPORT_TAGS
2412  cmd_free_tag( cmd );
2413 #else
2414  hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2415 #endif
2416  hostdata->connected = NULL;
2417  cmd->result = DID_ERROR << 16;
2418 #ifdef NCR5380_STATS
2419  collect_stats(hostdata, cmd);
2420 #endif
2421  cmd->scsi_done(cmd);
2423  return;
2424  }
2425  msgout = NOP;
2426  break;
2427  case PHASE_CMDOUT:
2428  len = cmd->cmd_len;
2429  data = cmd->cmnd;
2430  /*
2431  * XXX for performance reasons, on machines with a
2432  * PSEUDO-DMA architecture we should probably
2433  * use the dma transfer function.
2434  */
2435  NCR5380_transfer_pio(instance, &phase, &len,
2436  &data);
2437  break;
2438  case PHASE_STATIN:
2439  len = 1;
2440  data = &tmp;
2441  NCR5380_transfer_pio(instance, &phase, &len, &data);
2442  cmd->SCp.Status = tmp;
2443  break;
2444  default:
2445  printk("scsi%d: unknown phase\n", HOSTNO);
2447  } /* switch(phase) */
2448  } /* if (tmp * SR_REQ) */
2449  } /* while (1) */
2450 }
2451 
2452 /*
2453  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2454  *
2455  * Purpose : does reselection, initializing the instance->connected
2456  * field to point to the struct scsi_cmnd for which the I_T_L or I_T_L_Q
2457  * nexus has been reestablished,
2458  *
2459  * Inputs : instance - this instance of the NCR5380.
2460  *
2461  */
2462 
2463 /* it might eventually prove necessary to do a dma setup on
2464  reselection, but it doesn't seem to be needed now -- sam */
2465 
2466 static void NCR5380_reselect (struct Scsi_Host *instance)
2467 {
2468  SETUP_HOSTDATA(instance);
2469  unsigned char target_mask;
2470  unsigned char lun;
2471 #ifdef SUPPORT_TAGS
2472  unsigned char tag;
2473 #endif
2474  unsigned char msg[3];
2475  struct scsi_cmnd *tmp = NULL, *prev;
2476 /* unsigned long flags; */
2477 
2478  /*
2479  * Disable arbitration, etc. since the host adapter obviously
2480  * lost, and tell an interrupted NCR5380_select() to restart.
2481  */
2482 
2484  hostdata->restart_select = 1;
2485 
2486  target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2487 
2488  RSL_PRINTK("scsi%d: reselect\n", HOSTNO);
2489 
2490  /*
2491  * At this point, we have detected that our SCSI ID is on the bus,
2492  * SEL is true and BSY was false for at least one bus settle delay
2493  * (400 ns).
2494  *
2495  * We must assert BSY ourselves, until the target drops the SEL
2496  * signal.
2497  */
2498 
2500 
2501  while (NCR5380_read(STATUS_REG) & SR_SEL);
2503 
2504  /*
2505  * Wait for target to go into MSGIN.
2506  */
2507 
2508  while (!(NCR5380_read(STATUS_REG) & SR_REQ));
2509 
2510 #if 1
2511  // acknowledge toggle to MSGIN
2513 
2514  // peek at the byte without really hitting the bus
2516 #endif
2517 
2518  if (!(msg[0] & 0x80)) {
2519  printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
2520  spi_print_msg(msg);
2521  do_abort(instance);
2522  return;
2523  }
2524  lun = (msg[0] & 0x07);
2525 
2526  /*
2527  * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2528  * just reestablished, and remove it from the disconnected queue.
2529  */
2530 
2531  for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue, prev = NULL;
2532  tmp; prev = tmp, tmp = NEXT(tmp) ) {
2533  if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2534 #ifdef SUPPORT_TAGS
2535  && (tag == tmp->tag)
2536 #endif
2537  ) {
2538  if (prev) {
2539  REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2540  SET_NEXT(prev, NEXT(tmp));
2541  } else {
2542  REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
2543  hostdata->disconnected_queue = NEXT(tmp);
2544  }
2545  SET_NEXT(tmp, NULL);
2546  break;
2547  }
2548  }
2549 
2550  if (!tmp) {
2551  printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
2552 #ifdef SUPPORT_TAGS
2553  "tag %d "
2554 #endif
2555  "not in disconnected_queue.\n",
2556  HOSTNO, target_mask, lun
2557 #ifdef SUPPORT_TAGS
2558  , tag
2559 #endif
2560  );
2561  /*
2562  * Since we have an established nexus that we can't do anything
2563  * with, we must abort it.
2564  */
2565  do_abort(instance);
2566  return;
2567  }
2568 #if 1
2569  /* engage dma setup for the command we just saw */
2570  {
2571  void *d;
2572  unsigned long count;
2573 
2574  if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
2575  count = tmp->SCp.buffer->length;
2576  d = SGADDR(tmp->SCp.buffer);
2577  } else {
2578  count = tmp->SCp.this_residual;
2579  d = tmp->SCp.ptr;
2580  }
2581 #ifdef REAL_DMA
2582  /* setup this command for dma if not already */
2583  if((count > SUN3_DMA_MINSIZE) && (sun3_dma_setup_done != tmp))
2584  {
2585  sun3scsi_dma_setup(d, count, rq_data_dir(tmp->request));
2586  sun3_dma_setup_done = tmp;
2587  }
2588 #endif
2589  }
2590 #endif
2591 
2593  /* Accept message by clearing ACK */
2595 
2596 #ifdef SUPPORT_TAGS
2597  /* If the phase is still MSGIN, the target wants to send some more
2598  * messages. In case it supports tagged queuing, this is probably a
2599  * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2600  */
2601  tag = TAG_NONE;
2602  if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
2603  /* Accept previous IDENTIFY message by clearing ACK */
2605  len = 2;
2606  data = msg+1;
2607  if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2608  msg[1] == SIMPLE_QUEUE_TAG)
2609  tag = msg[2];
2610  TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at "
2611  "reselection\n", HOSTNO, target_mask, lun, tag);
2612  }
2613 #endif
2614 
2615  hostdata->connected = tmp;
2616  RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n",
2617  HOSTNO, tmp->target, tmp->lun, tmp->tag);
2618 }
2619 
2620 
2621 /*
2622  * Function : int NCR5380_abort(struct scsi_cmnd *cmd)
2623  *
2624  * Purpose : abort a command
2625  *
2626  * Inputs : cmd - the struct scsi_cmnd to abort, code - code to set the
2627  * host byte of the result field to, if zero DID_ABORTED is
2628  * used.
2629  *
2630  * Returns : 0 - success, -1 on failure.
2631  *
2632  * XXX - there is no way to abort the command that is currently
2633  * connected, you have to wait for it to complete. If this is
2634  * a problem, we could implement longjmp() / setjmp(), setjmp()
2635  * called where the loop started in NCR5380_main().
2636  */
2637 
2638 static int NCR5380_abort(struct scsi_cmnd *cmd)
2639 {
2640  struct Scsi_Host *instance = cmd->device->host;
2641  SETUP_HOSTDATA(instance);
2642  struct scsi_cmnd *tmp, **prev;
2643  unsigned long flags;
2644 
2645  printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO);
2646  scsi_print_command(cmd);
2647 
2648  NCR5380_print_status (instance);
2649 
2650  local_irq_save(flags);
2651 
2652  ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2655 
2656 #if 1
2657 /*
2658  * Case 1 : If the command is the currently executing command,
2659  * we'll set the aborted flag and return control so that
2660  * information transfer routine can exit cleanly.
2661  */
2662 
2663  if (hostdata->connected == cmd) {
2664 
2665  ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO);
2666 /*
2667  * We should perform BSY checking, and make sure we haven't slipped
2668  * into BUS FREE.
2669  */
2670 
2671 /* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2672 /*
2673  * Since we can't change phases until we've completed the current
2674  * handshake, we have to source or sink a byte of data if the current
2675  * phase is not MSGOUT.
2676  */
2677 
2678 /*
2679  * Return control to the executing NCR drive so we can clear the
2680  * aborted flag and get back into our main loop.
2681  */
2682 
2683  if (do_abort(instance) == 0) {
2684  hostdata->aborted = 1;
2685  hostdata->connected = NULL;
2686  cmd->result = DID_ABORT << 16;
2687 #ifdef SUPPORT_TAGS
2688  cmd_free_tag( cmd );
2689 #else
2690  hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2691 #endif
2692  local_irq_restore(flags);
2693  cmd->scsi_done(cmd);
2694  return SCSI_ABORT_SUCCESS;
2695  } else {
2696 /* local_irq_restore(flags); */
2697  printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2698  return SCSI_ABORT_ERROR;
2699  }
2700  }
2701 #endif
2702 
2703 /*
2704  * Case 2 : If the command hasn't been issued yet, we simply remove it
2705  * from the issue queue.
2706  */
2707  for (prev = (struct scsi_cmnd **) &(hostdata->issue_queue),
2708  tmp = (struct scsi_cmnd *) hostdata->issue_queue;
2709  tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp))
2710  if (cmd == tmp) {
2711  REMOVE(5, *prev, tmp, NEXT(tmp));
2712  (*prev) = NEXT(tmp);
2713  SET_NEXT(tmp, NULL);
2714  tmp->result = DID_ABORT << 16;
2715  local_irq_restore(flags);
2716  ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n",
2717  HOSTNO);
2718  /* Tagged queuing note: no tag to free here, hasn't been assigned
2719  * yet... */
2720  tmp->scsi_done(tmp);
2721  return SCSI_ABORT_SUCCESS;
2722  }
2723 
2724 /*
2725  * Case 3 : If any commands are connected, we're going to fail the abort
2726  * and let the high level SCSI driver retry at a later time or
2727  * issue a reset.
2728  *
2729  * Timeouts, and therefore aborted commands, will be highly unlikely
2730  * and handling them cleanly in this situation would make the common
2731  * case of noresets less efficient, and would pollute our code. So,
2732  * we fail.
2733  */
2734 
2735  if (hostdata->connected) {
2736  local_irq_restore(flags);
2737  ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO);
2738  return SCSI_ABORT_SNOOZE;
2739  }
2740 
2741 /*
2742  * Case 4: If the command is currently disconnected from the bus, and
2743  * there are no connected commands, we reconnect the I_T_L or
2744  * I_T_L_Q nexus associated with it, go into message out, and send
2745  * an abort message.
2746  *
2747  * This case is especially ugly. In order to reestablish the nexus, we
2748  * need to call NCR5380_select(). The easiest way to implement this
2749  * function was to abort if the bus was busy, and let the interrupt
2750  * handler triggered on the SEL for reselect take care of lost arbitrations
2751  * where necessary, meaning interrupts need to be enabled.
2752  *
2753  * When interrupts are enabled, the queues may change - so we
2754  * can't remove it from the disconnected queue before selecting it
2755  * because that could cause a failure in hashing the nexus if that
2756  * device reselected.
2757  *
2758  * Since the queues may change, we can't use the pointers from when we
2759  * first locate it.
2760  *
2761  * So, we must first locate the command, and if NCR5380_select()
2762  * succeeds, then issue the abort, relocate the command and remove
2763  * it from the disconnected queue.
2764  */
2765 
2766  for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue; tmp;
2767  tmp = NEXT(tmp))
2768  if (cmd == tmp) {
2769  local_irq_restore(flags);
2770  ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO);
2771 
2772  if (NCR5380_select (instance, cmd, (int) cmd->tag))
2773  return SCSI_ABORT_BUSY;
2774 
2775  ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO);
2776 
2777  do_abort (instance);
2778 
2779  local_irq_save(flags);
2780  for (prev = (struct scsi_cmnd **) &(hostdata->disconnected_queue),
2781  tmp = (struct scsi_cmnd *) hostdata->disconnected_queue;
2782  tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) )
2783  if (cmd == tmp) {
2784  REMOVE(5, *prev, tmp, NEXT(tmp));
2785  *prev = NEXT(tmp);
2786  SET_NEXT(tmp, NULL);
2787  tmp->result = DID_ABORT << 16;
2788  /* We must unlock the tag/LUN immediately here, since the
2789  * target goes to BUS FREE and doesn't send us another
2790  * message (COMMAND_COMPLETE or the like)
2791  */
2792 #ifdef SUPPORT_TAGS
2793  cmd_free_tag( tmp );
2794 #else
2795  hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2796 #endif
2797  local_irq_restore(flags);
2798  tmp->scsi_done(tmp);
2799  return SCSI_ABORT_SUCCESS;
2800  }
2801  }
2802 
2803 /*
2804  * Case 5 : If we reached this point, the command was not found in any of
2805  * the queues.
2806  *
2807  * We probably reached this point because of an unlikely race condition
2808  * between the command completing successfully and the abortion code,
2809  * so we won't panic, but we will notify the user in case something really
2810  * broke.
2811  */
2812 
2813  local_irq_restore(flags);
2814  printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO);
2815 
2816  return SCSI_ABORT_NOT_RUNNING;
2817 }
2818 
2819 
2820 /*
2821  * Function : int NCR5380_bus_reset(struct scsi_cmnd *cmd)
2822  *
2823  * Purpose : reset the SCSI bus.
2824  *
2825  * Returns : SCSI_RESET_WAKEUP
2826  *
2827  */
2828 
2829 static int NCR5380_bus_reset(struct scsi_cmnd *cmd)
2830 {
2831  SETUP_HOSTDATA(cmd->device->host);
2832  int i;
2833  unsigned long flags;
2834 #if 1
2835  struct scsi_cmnd *connected, *disconnected_queue;
2836 #endif
2837 
2838 
2839  NCR5380_print_status (cmd->device->host);
2840 
2841  /* get in phase */
2844  /* assert RST */
2846  udelay (40);
2847  /* reset NCR registers */
2852  /* ++roman: reset interrupt condition! otherwise no interrupts don't get
2853  * through anymore ... */
2855 
2856 #if 1 /* XXX Should now be done by midlevel code, but it's broken XXX */
2857  /* XXX see below XXX */
2858 
2859  /* MSch: old-style reset: actually abort all command processing here */
2860 
2861  /* After the reset, there are no more connected or disconnected commands
2862  * and no busy units; to avoid problems with re-inserting the commands
2863  * into the issue_queue (via scsi_done()), the aborted commands are
2864  * remembered in local variables first.
2865  */
2866  local_irq_save(flags);
2867  connected = (struct scsi_cmnd *)hostdata->connected;
2868  hostdata->connected = NULL;
2869  disconnected_queue = (struct scsi_cmnd *)hostdata->disconnected_queue;
2870  hostdata->disconnected_queue = NULL;
2871 #ifdef SUPPORT_TAGS
2872  free_all_tags();
2873 #endif
2874  for( i = 0; i < 8; ++i )
2875  hostdata->busy[i] = 0;
2876 #ifdef REAL_DMA
2877  hostdata->dma_len = 0;
2878 #endif
2879  local_irq_restore(flags);
2880 
2881  /* In order to tell the mid-level code which commands were aborted,
2882  * set the command status to DID_RESET and call scsi_done() !!!
2883  * This ultimately aborts processing of these commands in the mid-level.
2884  */
2885 
2886  if ((cmd = connected)) {
2887  ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2888  cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2889  cmd->scsi_done( cmd );
2890  }
2891 
2892  for (i = 0; (cmd = disconnected_queue); ++i) {
2893  disconnected_queue = NEXT(cmd);
2894  SET_NEXT(cmd, NULL);
2895  cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2896  cmd->scsi_done( cmd );
2897  }
2898  if (i > 0)
2899  ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i);
2900 
2901 
2902  /* since all commands have been explicitly terminated, we need to tell
2903  * the midlevel code that the reset was SUCCESSFUL, and there is no
2904  * need to 'wake up' the commands by a request_sense
2905  */
2907 #else /* 1 */
2908 
2909  /* MSch: new-style reset handling: let the mid-level do what it can */
2910 
2911  /* ++guenther: MID-LEVEL IS STILL BROKEN.
2912  * Mid-level is supposed to requeue all commands that were active on the
2913  * various low-level queues. In fact it does this, but that's not enough
2914  * because all these commands are subject to timeout. And if a timeout
2915  * happens for any removed command, *_abort() is called but all queues
2916  * are now empty. Abort then gives up the falcon lock, which is fatal,
2917  * since the mid-level will queue more commands and must have the lock
2918  * (it's all happening inside timer interrupt handler!!).
2919  * Even worse, abort will return NOT_RUNNING for all those commands not
2920  * on any queue, so they won't be retried ...
2921  *
2922  * Conclusion: either scsi.c disables timeout for all resetted commands
2923  * immediately, or we lose! As of linux-2.0.20 it doesn't.
2924  */
2925 
2926  /* After the reset, there are no more connected or disconnected commands
2927  * and no busy units; so clear the low-level status here to avoid
2928  * conflicts when the mid-level code tries to wake up the affected
2929  * commands!
2930  */
2931 
2932  if (hostdata->issue_queue)
2933  ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2934  if (hostdata->connected)
2935  ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2936  if (hostdata->disconnected_queue)
2937  ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
2938 
2939  local_irq_save(flags);
2940  hostdata->issue_queue = NULL;
2941  hostdata->connected = NULL;
2942  hostdata->disconnected_queue = NULL;
2943 #ifdef SUPPORT_TAGS
2944  free_all_tags();
2945 #endif
2946  for( i = 0; i < 8; ++i )
2947  hostdata->busy[i] = 0;
2948 #ifdef REAL_DMA
2949  hostdata->dma_len = 0;
2950 #endif
2951  local_irq_restore(flags);
2952 
2953  /* we did no complete reset of all commands, so a wakeup is required */
2955 #endif /* 1 */
2956 }
2957 
2958 /* Local Variables: */
2959 /* tab-width: 8 */
2960 /* End: */