File: /usr/src/linux/drivers/scsi/atari_NCR5380.c
1 /*
2 * NCR 5380 generic driver routines. These should make it *trivial*
3 * to implement 5380 SCSI drivers under Linux with a non-trantor
4 * architecture.
5 *
6 * Note that these routines also work with NR53c400 family chips.
7 *
8 * Copyright 1993, Drew Eckhardt
9 * Visionary Computing
10 * (Unix and Linux consulting and custom programming)
11 * drew@colorado.edu
12 * +1 (303) 666-5836
13 *
14 * DISTRIBUTION RELEASE 6.
15 *
16 * For more information, please consult
17 *
18 * NCR 5380 Family
19 * SCSI Protocol Controller
20 * Databook
21 *
22 * NCR Microelectronics
23 * 1635 Aeroplaza Drive
24 * Colorado Springs, CO 80916
25 * 1+ (719) 578-3400
26 * 1+ (800) 334-5454
27 */
28
29 /*
30 * ++roman: To port the 5380 driver to the Atari, I had to do some changes in
31 * this file, too:
32 *
33 * - Some of the debug statements were incorrect (undefined variables and the
34 * like). I fixed that.
35 *
36 * - In information_transfer(), I think a #ifdef was wrong. Looking at the
37 * possible DMA transfer size should also happen for REAL_DMA. I added this
38 * in the #if statement.
39 *
40 * - When using real DMA, information_transfer() should return in a DATAOUT
41 * phase after starting the DMA. It has nothing more to do.
42 *
43 * - The interrupt service routine should run main after end of DMA, too (not
44 * only after RESELECTION interrupts). Additionally, it should _not_ test
45 * for more interrupts after running main, since a DMA process may have
46 * been started and interrupts are turned on now. The new int could happen
47 * inside the execution of NCR5380_intr(), leading to recursive
48 * calls.
49 *
50 * - I've added a function merge_contiguous_buffers() that tries to
51 * merge scatter-gather buffers that are located at contiguous
52 * physical addresses and can be processed with the same DMA setup.
53 * Since most scatter-gather operations work on a page (4K) of
54 * 4 buffers (1K), in more than 90% of all cases three interrupts and
55 * DMA setup actions are saved.
56 *
57 * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA
58 * and USLEEP, because these were messing up readability and will never be
59 * needed for Atari SCSI.
60 *
61 * - I've revised the NCR5380_main() calling scheme (relax the 'main_running'
62 * stuff), and 'main' is executed in a bottom half if awoken by an
63 * interrupt.
64 *
65 * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..."
66 * constructs. In my eyes, this made the source rather unreadable, so I
67 * finally replaced that by the *_PRINTK() macros.
68 *
69 */
70
71 /*
72 * Further development / testing that should be done :
73 * 1. Test linked command handling code after Eric is ready with
74 * the high level code.
75 */
76
77 #if (NDEBUG & NDEBUG_LISTS)
78 #define LIST(x,y) \
79 { printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); \
80 if ((x)==(y)) udelay(5); }
81 #define REMOVE(w,x,y,z) \
82 { printk("LINE:%d Removing: %p->%p %p->%p \n", __LINE__, \
83 (void*)(w), (void*)(x), (void*)(y), (void*)(z)); \
84 if ((x)==(y)) udelay(5); }
85 #else
86 #define LIST(x,y)
87 #define REMOVE(w,x,y,z)
88 #endif
89
90 #ifndef notyet
91 #undef LINKED
92 #endif
93
94 /*
95 * Design
96 * Issues :
97 *
98 * The other Linux SCSI drivers were written when Linux was Intel PC-only,
99 * and specifically for each board rather than each chip. This makes their
100 * adaptation to platforms like the Mac (Some of which use NCR5380's)
101 * more difficult than it has to be.
102 *
103 * Also, many of the SCSI drivers were written before the command queuing
104 * routines were implemented, meaning their implementations of queued
105 * commands were hacked on rather than designed in from the start.
106 *
107 * When I designed the Linux SCSI drivers I figured that
108 * while having two different SCSI boards in a system might be useful
109 * for debugging things, two of the same type wouldn't be used.
110 * Well, I was wrong and a number of users have mailed me about running
111 * multiple high-performance SCSI boards in a server.
112 *
113 * Finally, when I get questions from users, I have no idea what
114 * revision of my driver they are running.
115 *
116 * This driver attempts to address these problems :
117 * This is a generic 5380 driver. To use it on a different platform,
118 * one simply writes appropriate system specific macros (ie, data
119 * transfer - some PC's will use the I/O bus, 68K's must use
120 * memory mapped) and drops this file in their 'C' wrapper.
121 *
122 * As far as command queueing, two queues are maintained for
123 * each 5380 in the system - commands that haven't been issued yet,
124 * and commands that are currently executing. This means that an
125 * unlimited number of commands may be queued, letting
126 * more commands propagate from the higher driver levels giving higher
127 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
128 * allowing multiple commands to propagate all the way to a SCSI-II device
129 * while a command is already executing.
130 *
131 * To solve the multiple-boards-in-the-same-system problem,
132 * there is a separate instance structure for each instance
133 * of a 5380 in the system. So, multiple NCR5380 drivers will
134 * be able to coexist with appropriate changes to the high level
135 * SCSI code.
136 *
137 * A NCR5380_PUBLIC_REVISION macro is provided, with the release
138 * number (updated for each public release) printed by the
139 * NCR5380_print_options command, which should be called from the
140 * wrapper detect function, so that I know what release of the driver
141 * users are using.
142 *
143 * Issues specific to the NCR5380 :
144 *
145 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
146 * piece of hardware that requires you to sit in a loop polling for
147 * the REQ signal as long as you are connected. Some devices are
148 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
149 * while doing long seek operations.
150 *
151 * The workaround for this is to keep track of devices that have
152 * disconnected. If the device hasn't disconnected, for commands that
153 * should disconnect, we do something like
154 *
155 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
156 *
157 * Some tweaking of N and M needs to be done. An algorithm based
158 * on "time to data" would give the best results as long as short time
159 * to datas (ie, on the same track) were considered, however these
160 * broken devices are the exception rather than the rule and I'd rather
161 * spend my time optimizing for the normal case.
162 *
163 * Architecture :
164 *
165 * At the heart of the design is a coroutine, NCR5380_main,
166 * which is started when not running by the interrupt handler,
167 * timer, and queue command function. It attempts to establish
168 * I_T_L or I_T_L_Q nexuses by removing the commands from the
169 * issue queue and calling NCR5380_select() if a nexus
170 * is not established.
171 *
172 * Once a nexus is established, the NCR5380_information_transfer()
173 * phase goes through the various phases as instructed by the target.
174 * if the target goes into MSG IN and sends a DISCONNECT message,
175 * the command structure is placed into the per instance disconnected
176 * queue, and NCR5380_main tries to find more work. If USLEEP
177 * was defined, and the target is idle for too long, the system
178 * will try to sleep.
179 *
180 * If a command has disconnected, eventually an interrupt will trigger,
181 * calling NCR5380_intr() which will in turn call NCR5380_reselect
182 * to reestablish a nexus. This will run main if necessary.
183 *
184 * On command termination, the done function will be called as
185 * appropriate.
186 *
187 * SCSI pointers are maintained in the SCp field of SCSI command
188 * structures, being initialized after the command is connected
189 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
190 * Note that in violation of the standard, an implicit SAVE POINTERS operation
191 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
192 */
193
194 /*
195 * Using this file :
196 * This file a skeleton Linux SCSI driver for the NCR 5380 series
197 * of chips. To use it, you write an architecture specific functions
198 * and macros and include this file in your driver.
199 *
200 * These macros control options :
201 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
202 * for commands that return with a CHECK CONDITION status.
203 *
204 * LINKED - if defined, linked commands are supported.
205 *
206 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
207 *
208 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
209 *
210 * These macros MUST be defined :
211 *
212 * NCR5380_read(register) - read from the specified register
213 *
214 * NCR5380_write(register, value) - write to the specific register
215 *
216 * Either real DMA *or* pseudo DMA may be implemented
217 * REAL functions :
218 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
219 * Note that the DMA setup functions should return the number of bytes
220 * that they were able to program the controller for.
221 *
222 * Also note that generic i386/PC versions of these macros are
223 * available as NCR5380_i386_dma_write_setup,
224 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
225 *
226 * NCR5380_dma_write_setup(instance, src, count) - initialize
227 * NCR5380_dma_read_setup(instance, dst, count) - initialize
228 * NCR5380_dma_residual(instance); - residual count
229 *
230 * PSEUDO functions :
231 * NCR5380_pwrite(instance, src, count)
232 * NCR5380_pread(instance, dst, count);
233 *
234 * If nothing specific to this implementation needs doing (ie, with external
235 * hardware), you must also define
236 *
237 * NCR5380_queue_command
238 * NCR5380_reset
239 * NCR5380_abort
240 * NCR5380_proc_info
241 *
242 * to be the global entry points into the specific driver, ie
243 * #define NCR5380_queue_command t128_queue_command.
244 *
245 * If this is not done, the routines will be defined as static functions
246 * with the NCR5380* names and the user must provide a globally
247 * accessible wrapper function.
248 *
249 * The generic driver is initialized by calling NCR5380_init(instance),
250 * after setting the appropriate host specific fields and ID. If the
251 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
252 * possible) function may be used. Before the specific driver initialization
253 * code finishes, NCR5380_print_options should be called.
254 */
255
256 static struct Scsi_Host *first_instance = NULL;
257 static Scsi_Host_Template *the_template = NULL;
258
259 /* Macros ease life... :-) */
260 #define SETUP_HOSTDATA(in) \
261 struct NCR5380_hostdata *hostdata = \
262 (struct NCR5380_hostdata *)(in)->hostdata
263 #define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)
264
265 #define NEXT(cmd) ((Scsi_Cmnd *)((cmd)->host_scribble))
266 #define NEXTADDR(cmd) ((Scsi_Cmnd **)&((cmd)->host_scribble))
267
268 #define HOSTNO instance->host_no
269 #define H_NO(cmd) (cmd)->host->host_no
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( Scsi_Cmnd *cmd, int should_be_tagged )
357 {
358 SETUP_HOSTDATA(cmd->host);
359
360 if (hostdata->busy[cmd->target] & (1 << cmd->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->target][cmd->lun].nr_allocated >=
366 TagAlloc[cmd->target][cmd->lun].queue_size ) {
367 TAG_PRINTK( "scsi%d: target %d lun %d: no free tags\n",
368 H_NO(cmd), cmd->target, cmd->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( Scsi_Cmnd *cmd, int should_be_tagged )
381 {
382 SETUP_HOSTDATA(cmd->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->target] |= (1 << cmd->lun);
391 TAG_PRINTK( "scsi%d: target %d lun %d now allocated by untagged "
392 "command\n", H_NO(cmd), cmd->target, cmd->lun );
393 }
394 else {
395 TAG_ALLOC *ta = &TagAlloc[cmd->target][cmd->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->target, cmd->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( Scsi_Cmnd *cmd )
413 {
414 SETUP_HOSTDATA(cmd->host);
415
416 if (cmd->tag == TAG_NONE) {
417 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
418 TAG_PRINTK( "scsi%d: target %d lun %d untagged cmd finished\n",
419 H_NO(cmd), cmd->target, cmd->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->target][cmd->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->target, cmd->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 merge_contiguous_buffers( Scsi_Cmnd *cmd )
457 *
458 * Purpose: Try to merge several scatter-gather requests into one DMA
459 * transfer. This is possible if the scatter buffers lie on
460 * physical contiguous addresses.
461 *
462 * Parameters: Scsi_Cmnd *cmd
463 * The command to work on. The first scatter buffer's data are
464 * assumed to be already transfered into ptr/this_residual.
465 */
466
467 static void merge_contiguous_buffers( Scsi_Cmnd *cmd )
468 {
469 unsigned long endaddr;
470 #if (NDEBUG & NDEBUG_MERGING)
471 unsigned long oldlen = cmd->SCp.this_residual;
472 int cnt = 1;
473 #endif
474
475 for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
476 cmd->SCp.buffers_residual &&
477 virt_to_phys(cmd->SCp.buffer[1].address) == endaddr; ) {
478
479 MER_PRINTK("VTOP(%p) == %08lx -> merging\n",
480 cmd->SCp.buffer[1].address, endaddr);
481 #if (NDEBUG & NDEBUG_MERGING)
482 ++cnt;
483 #endif
484 ++cmd->SCp.buffer;
485 --cmd->SCp.buffers_residual;
486 cmd->SCp.this_residual += cmd->SCp.buffer->length;
487 endaddr += cmd->SCp.buffer->length;
488 }
489 #if (NDEBUG & NDEBUG_MERGING)
490 if (oldlen != cmd->SCp.this_residual)
491 MER_PRINTK("merged %d buffers from %p, new length %08x\n",
492 cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
493 #endif
494 }
495
496 /*
497 * Function : void initialize_SCp(Scsi_Cmnd *cmd)
498 *
499 * Purpose : initialize the saved data pointers for cmd to point to the
500 * start of the buffer.
501 *
502 * Inputs : cmd - Scsi_Cmnd structure to have pointers reset.
503 */
504
505 static __inline__ void initialize_SCp(Scsi_Cmnd *cmd)
506 {
507 /*
508 * Initialize the Scsi Pointer field so that all of the commands in the
509 * various queues are valid.
510 */
511
512 if (cmd->use_sg) {
513 cmd->SCp.buffer = (struct scatterlist *) cmd->buffer;
514 cmd->SCp.buffers_residual = cmd->use_sg - 1;
515 cmd->SCp.ptr = (char *) cmd->SCp.buffer->address;
516 cmd->SCp.this_residual = cmd->SCp.buffer->length;
517 /* ++roman: Try to merge some scatter-buffers if they are at
518 * contiguous physical addresses.
519 */
520 merge_contiguous_buffers( cmd );
521 } else {
522 cmd->SCp.buffer = NULL;
523 cmd->SCp.buffers_residual = 0;
524 cmd->SCp.ptr = (char *) cmd->request_buffer;
525 cmd->SCp.this_residual = cmd->request_bufflen;
526 }
527 }
528
529 #include <linux/config.h>
530 #include <linux/delay.h>
531
532 #if NDEBUG
533 static struct {
534 unsigned char mask;
535 const char * name;}
536 signals[] = {{ SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" },
537 { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" },
538 { SR_SEL, "SEL" }, {0, NULL}},
539 basrs[] = {{BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}},
540 icrs[] = {{ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"},
541 {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"},
542 {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"},
543 {0, NULL}},
544 mrs[] = {{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"},
545 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR,
546 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"},
547 {MR_MONITOR_BSY, "MODE MONITOR BSY"},
548 {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"},
549 {0, NULL}};
550
551 /*
552 * Function : void NCR5380_print(struct Scsi_Host *instance)
553 *
554 * Purpose : print the SCSI bus signals for debugging purposes
555 *
556 * Input : instance - which NCR5380
557 */
558
559 static void NCR5380_print(struct Scsi_Host *instance) {
560 unsigned char status, data, basr, mr, icr, i;
561 unsigned long flags;
562
563 save_flags(flags);
564 cli();
565 data = NCR5380_read(CURRENT_SCSI_DATA_REG);
566 status = NCR5380_read(STATUS_REG);
567 mr = NCR5380_read(MODE_REG);
568 icr = NCR5380_read(INITIATOR_COMMAND_REG);
569 basr = NCR5380_read(BUS_AND_STATUS_REG);
570 restore_flags(flags);
571 printk("STATUS_REG: %02x ", status);
572 for (i = 0; signals[i].mask ; ++i)
573 if (status & signals[i].mask)
574 printk(",%s", signals[i].name);
575 printk("\nBASR: %02x ", basr);
576 for (i = 0; basrs[i].mask ; ++i)
577 if (basr & basrs[i].mask)
578 printk(",%s", basrs[i].name);
579 printk("\nICR: %02x ", icr);
580 for (i = 0; icrs[i].mask; ++i)
581 if (icr & icrs[i].mask)
582 printk(",%s", icrs[i].name);
583 printk("\nMODE: %02x ", mr);
584 for (i = 0; mrs[i].mask; ++i)
585 if (mr & mrs[i].mask)
586 printk(",%s", mrs[i].name);
587 printk("\n");
588 }
589
590 static struct {
591 unsigned char value;
592 const char *name;
593 } phases[] = {
594 {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
595 {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
596 {PHASE_UNKNOWN, "UNKNOWN"}};
597
598 /*
599 * Function : void NCR5380_print_phase(struct Scsi_Host *instance)
600 *
601 * Purpose : print the current SCSI phase for debugging purposes
602 *
603 * Input : instance - which NCR5380
604 */
605
606 static void NCR5380_print_phase(struct Scsi_Host *instance)
607 {
608 unsigned char status;
609 int i;
610
611 status = NCR5380_read(STATUS_REG);
612 if (!(status & SR_REQ))
613 printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO);
614 else {
615 for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
616 (phases[i].value != (status & PHASE_MASK)); ++i);
617 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name);
618 }
619 }
620
621 #else /* !NDEBUG */
622
623 /* dummies... */
624 __inline__ void NCR5380_print(struct Scsi_Host *instance) { };
625 __inline__ void NCR5380_print_phase(struct Scsi_Host *instance) { };
626
627 #endif
628
629 /*
630 * ++roman: New scheme of calling NCR5380_main()
631 *
632 * If we're not in an interrupt, we can call our main directly, it cannot be
633 * already running. Else, we queue it on a task queue, if not 'main_running'
634 * tells us that a lower level is already executing it. This way,
635 * 'main_running' needs not be protected in a special way.
636 *
637 * queue_main() is a utility function for putting our main onto the task
638 * queue, if main_running is false. It should be called only from a
639 * interrupt or bottom half.
640 */
641
642 #include <linux/tqueue.h>
643 #include <linux/interrupt.h>
644
645 static volatile int main_running = 0;
646 static struct tq_struct NCR5380_tqueue = {
647 NULL, /* next */
648 0, /* sync */
649 (void (*)(void*))NCR5380_main, /* routine, must have (void *) arg... */
650 NULL /* data */
651 };
652
653 static __inline__ void queue_main(void)
654 {
655 if (!main_running) {
656 /* If in interrupt and NCR5380_main() not already running,
657 queue it on the 'immediate' task queue, to be processed
658 immediately after the current interrupt processing has
659 finished. */
660 queue_task(&NCR5380_tqueue, &tq_immediate);
661 mark_bh(IMMEDIATE_BH);
662 }
663 /* else: nothing to do: the running NCR5380_main() will pick up
664 any newly queued command. */
665 }
666
667
668 static inline void NCR5380_all_init (void)
669 {
670 static int done = 0;
671 if (!done) {
672 INI_PRINTK("scsi : NCR5380_all_init()\n");
673 done = 1;
674 }
675 }
676
677
678 /*
679 * Function : void NCR58380_print_options (struct Scsi_Host *instance)
680 *
681 * Purpose : called by probe code indicating the NCR5380 driver
682 * options that were selected.
683 *
684 * Inputs : instance, pointer to this instance. Unused.
685 */
686
687 static void __init NCR5380_print_options (struct Scsi_Host *instance)
688 {
689 printk(" generic options"
690 #ifdef AUTOSENSE
691 " AUTOSENSE"
692 #endif
693 #ifdef REAL_DMA
694 " REAL DMA"
695 #endif
696 #ifdef PARITY
697 " PARITY"
698 #endif
699 #ifdef SUPPORT_TAGS
700 " SCSI-2 TAGGED QUEUING"
701 #endif
702 );
703 printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
704 }
705
706 /*
707 * Function : void NCR5380_print_status (struct Scsi_Host *instance)
708 *
709 * Purpose : print commands in the various queues, called from
710 * NCR5380_abort and NCR5380_debug to aid debugging.
711 *
712 * Inputs : instance, pointer to this instance.
713 */
714
715 static void NCR5380_print_status (struct Scsi_Host *instance)
716 {
717 char *pr_bfr;
718 char *start;
719 int len;
720
721 NCR_PRINT(NDEBUG_ANY);
722 NCR_PRINT_PHASE(NDEBUG_ANY);
723
724 pr_bfr = (char *) __get_free_page(GFP_ATOMIC);
725 if (!pr_bfr) {
726 printk("NCR5380_print_status: no memory for print buffer\n");
727 return;
728 }
729 len = NCR5380_proc_info(pr_bfr, &start, 0, PAGE_SIZE, HOSTNO, 0);
730 pr_bfr[len] = 0;
731 printk("\n%s\n", pr_bfr);
732 free_page((unsigned long) pr_bfr);
733 }
734
735
736 /******************************************/
737 /*
738 * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
739 *
740 * *buffer: I/O buffer
741 * **start: if inout == FALSE pointer into buffer where user read should start
742 * offset: current offset
743 * length: length of buffer
744 * hostno: Scsi_Host host_no
745 * inout: TRUE - user is writing; FALSE - user is reading
746 *
747 * Return the number of bytes read from or written
748 */
749
750 #undef SPRINTF
751 #define SPRINTF(fmt,args...) \
752 do { if (pos + strlen(fmt) + 20 /* slop */ < buffer + length) \
753 pos += sprintf(pos, fmt , ## args); } while(0)
754 static
755 char *lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length);
756
757 #ifndef NCR5380_proc_info
758 static
759 #endif
760 int NCR5380_proc_info (char *buffer, char **start, off_t offset,
761 int length, int hostno, int inout)
762 {
763 char *pos = buffer;
764 struct Scsi_Host *instance;
765 struct NCR5380_hostdata *hostdata;
766 Scsi_Cmnd *ptr;
767 unsigned long flags;
768 off_t begin = 0;
769 #define check_offset() \
770 do { \
771 if (pos - buffer < offset - begin) { \
772 begin += pos - buffer; \
773 pos = buffer; \
774 } \
775 } while (0)
776
777 for (instance = first_instance; instance && HOSTNO != hostno;
778 instance = instance->next)
779 ;
780 if (!instance)
781 return(-ESRCH);
782 hostdata = (struct NCR5380_hostdata *)instance->hostdata;
783
784 if (inout) { /* Has data been written to the file ? */
785 return(-ENOSYS); /* Currently this is a no-op */
786 }
787 SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
788 check_offset();
789 save_flags(flags);
790 cli();
791 SPRINTF("NCR5380: coroutine is%s running.\n", main_running ? "" : "n't");
792 check_offset();
793 if (!hostdata->connected)
794 SPRINTF("scsi%d: no currently connected command\n", HOSTNO);
795 else
796 pos = lprint_Scsi_Cmnd ((Scsi_Cmnd *) hostdata->connected,
797 pos, buffer, length);
798 SPRINTF("scsi%d: issue_queue\n", HOSTNO);
799 check_offset();
800 for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = NEXT(ptr)) {
801 pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
802 check_offset();
803 }
804
805 SPRINTF("scsi%d: disconnected_queue\n", HOSTNO);
806 check_offset();
807 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr;
808 ptr = NEXT(ptr)) {
809 pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
810 check_offset();
811 }
812
813 restore_flags(flags);
814 *start = buffer + (offset - begin);
815 if (pos - buffer < offset - begin)
816 return 0;
817 else if (pos - buffer - (offset - begin) < length)
818 return pos - buffer - (offset - begin);
819 return length;
820 }
821
822 static char *
823 lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length)
824 {
825 int i, s;
826 unsigned char *command;
827 SPRINTF("scsi%d: destination target %d, lun %d\n",
828 H_NO(cmd), cmd->target, cmd->lun);
829 SPRINTF(" command = ");
830 command = cmd->cmnd;
831 SPRINTF("%2d (0x%02x)", command[0], command[0]);
832 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
833 SPRINTF(" %02x", command[i]);
834 SPRINTF("\n");
835 return pos;
836 }
837
838
839 /*
840 * Function : void NCR5380_init (struct Scsi_Host *instance)
841 *
842 * Purpose : initializes *instance and corresponding 5380 chip.
843 *
844 * Inputs : instance - instantiation of the 5380 driver.
845 *
846 * Notes : I assume that the host, hostno, and id bits have been
847 * set correctly. I don't care about the irq and other fields.
848 *
849 */
850
851 static void __init NCR5380_init (struct Scsi_Host *instance, int flags)
852 {
853 int i;
854 SETUP_HOSTDATA(instance);
855
856 NCR5380_all_init();
857
858 hostdata->aborted = 0;
859 hostdata->id_mask = 1 << instance->this_id;
860 hostdata->id_higher_mask = 0;
861 for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
862 if (i > hostdata->id_mask)
863 hostdata->id_higher_mask |= i;
864 for (i = 0; i < 8; ++i)
865 hostdata->busy[i] = 0;
866 #ifdef SUPPORT_TAGS
867 init_tags();
868 #endif
869 #if defined (REAL_DMA)
870 hostdata->dma_len = 0;
871 #endif
872 hostdata->targets_present = 0;
873 hostdata->connected = NULL;
874 hostdata->issue_queue = NULL;
875 hostdata->disconnected_queue = NULL;
876 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT;
877
878 if (!the_template) {
879 the_template = instance->hostt;
880 first_instance = instance;
881 }
882
883
884 #ifndef AUTOSENSE
885 if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1))
886 printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n"
887 " without AUTOSENSE option, contingent allegiance conditions may\n"
888 " be incorrectly cleared.\n", HOSTNO);
889 #endif /* def AUTOSENSE */
890
891 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
892 NCR5380_write(MODE_REG, MR_BASE);
893 NCR5380_write(TARGET_COMMAND_REG, 0);
894 NCR5380_write(SELECT_ENABLE_REG, 0);
895 }
896
897 /*
898 * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd,
899 * void (*done)(Scsi_Cmnd *))
900 *
901 * Purpose : enqueues a SCSI command
902 *
903 * Inputs : cmd - SCSI command, done - function called on completion, with
904 * a pointer to the command descriptor.
905 *
906 * Returns : 0
907 *
908 * Side effects :
909 * cmd is added to the per instance issue_queue, with minor
910 * twiddling done to the host specific fields of cmd. If the
911 * main coroutine is not running, it is restarted.
912 *
913 */
914
915 /* Only make static if a wrapper function is used */
916 #ifndef NCR5380_queue_command
917 static
918 #endif
919 int NCR5380_queue_command (Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
920 {
921 SETUP_HOSTDATA(cmd->host);
922 Scsi_Cmnd *tmp;
923 int oldto;
924 unsigned long flags;
925 extern int update_timeout(Scsi_Cmnd * SCset, int timeout);
926
927 #if (NDEBUG & NDEBUG_NO_WRITE)
928 switch (cmd->cmnd[0]) {
929 case WRITE_6:
930 case WRITE_10:
931 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
932 H_NO(cmd));
933 cmd->result = (DID_ERROR << 16);
934 done(cmd);
935 return 0;
936 }
937 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
938
939
940 #ifdef NCR5380_STATS
941 # if 0
942 if (!hostdata->connected && !hostdata->issue_queue &&
943 !hostdata->disconnected_queue) {
944 hostdata->timebase = jiffies;
945 }
946 # endif
947 # ifdef NCR5380_STAT_LIMIT
948 if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
949 # endif
950 switch (cmd->cmnd[0])
951 {
952 case WRITE:
953 case WRITE_6:
954 case WRITE_10:
955 hostdata->time_write[cmd->target] -= (jiffies - hostdata->timebase);
956 hostdata->bytes_write[cmd->target] += cmd->request_bufflen;
957 hostdata->pendingw++;
958 break;
959 case READ:
960 case READ_6:
961 case READ_10:
962 hostdata->time_read[cmd->target] -= (jiffies - hostdata->timebase);
963 hostdata->bytes_read[cmd->target] += cmd->request_bufflen;
964 hostdata->pendingr++;
965 break;
966 }
967 #endif
968
969 /*
970 * We use the host_scribble field as a pointer to the next command
971 * in a queue
972 */
973
974 NEXT(cmd) = NULL;
975 cmd->scsi_done = done;
976
977 cmd->result = 0;
978
979
980 /*
981 * Insert the cmd into the issue queue. Note that REQUEST SENSE
982 * commands are added to the head of the queue since any command will
983 * clear the contingent allegiance condition that exists and the
984 * sense data is only guaranteed to be valid while the condition exists.
985 */
986
987 save_flags(flags);
988 cli();
989 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
990 * Otherwise a running NCR5380_main may steal the lock.
991 * Lock before actually inserting due to fairness reasons explained in
992 * atari_scsi.c. If we insert first, then it's impossible for this driver
993 * to release the lock.
994 * Stop timer for this command while waiting for the lock, or timeouts
995 * may happen (and they really do), and it's no good if the command doesn't
996 * appear in any of the queues.
997 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
998 * because also a timer int can trigger an abort or reset, which would
999 * alter queues and touch the lock.
1000 */
1001 if (!IS_A_TT()) {
1002 oldto = update_timeout(cmd, 0);
1003 falcon_get_lock();
1004 update_timeout(cmd, oldto);
1005 }
1006 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
1007 LIST(cmd, hostdata->issue_queue);
1008 NEXT(cmd) = hostdata->issue_queue;
1009 hostdata->issue_queue = cmd;
1010 } else {
1011 for (tmp = (Scsi_Cmnd *)hostdata->issue_queue;
1012 NEXT(tmp); tmp = NEXT(tmp))
1013 ;
1014 LIST(cmd, tmp);
1015 NEXT(tmp) = cmd;
1016 }
1017 restore_flags(flags);
1018
1019 QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd),
1020 (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
1021
1022 /* If queue_command() is called from an interrupt (real one or bottom
1023 * half), we let queue_main() do the job of taking care about main. If it
1024 * is already running, this is a no-op, else main will be queued.
1025 *
1026 * If we're not in an interrupt, we can call NCR5380_main()
1027 * unconditionally, because it cannot be already running.
1028 */
1029 if (in_interrupt() || ((flags >> 8) & 7) >= 6)
1030 queue_main();
1031 else
1032 NCR5380_main();
1033 return 0;
1034 }
1035
1036 /*
1037 * Function : NCR5380_main (void)
1038 *
1039 * Purpose : NCR5380_main is a coroutine that runs as long as more work can
1040 * be done on the NCR5380 host adapters in a system. Both
1041 * NCR5380_queue_command() and NCR5380_intr() will try to start it
1042 * in case it is not running.
1043 *
1044 * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
1045 * reenable them. This prevents reentrancy and kernel stack overflow.
1046 */
1047
1048 static void NCR5380_main (void)
1049 {
1050 Scsi_Cmnd *tmp, *prev;
1051 struct Scsi_Host *instance = first_instance;
1052 struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
1053 int done;
1054 unsigned long flags;
1055
1056 /*
1057 * We run (with interrupts disabled) until we're sure that none of
1058 * the host adapters have anything that can be done, at which point
1059 * we set main_running to 0 and exit.
1060 *
1061 * Interrupts are enabled before doing various other internal
1062 * instructions, after we've decided that we need to run through
1063 * the loop again.
1064 *
1065 * this should prevent any race conditions.
1066 *
1067 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1068 * because also a timer int can trigger an abort or reset, which can
1069 * alter queues and touch the Falcon lock.
1070 */
1071
1072 /* Tell int handlers main() is now already executing. Note that
1073 no races are possible here. If an int comes in before
1074 'main_running' is set here, and queues/executes main via the
1075 task queue, it doesn't do any harm, just this instance of main
1076 won't find any work left to do. */
1077 if (main_running)
1078 return;
1079 main_running = 1;
1080
1081 save_flags(flags);
1082 do {
1083 cli(); /* Freeze request queues */
1084 done = 1;
1085
1086 if (!hostdata->connected) {
1087 MAIN_PRINTK( "scsi%d: not connected\n", HOSTNO );
1088 /*
1089 * Search through the issue_queue for a command destined
1090 * for a target that's not busy.
1091 */
1092 #if (NDEBUG & NDEBUG_LISTS)
1093 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL;
1094 tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
1095 ;
1096 /*printk("%p ", tmp);*/
1097 if ((tmp == prev) && tmp) printk(" LOOP\n");/* else printk("\n");*/
1098 #endif
1099 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue,
1100 prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp) ) {
1101
1102 #if (NDEBUG & NDEBUG_LISTS)
1103 if (prev != tmp)
1104 printk("MAIN tmp=%p target=%d busy=%d lun=%d\n",
1105 tmp, tmp->target, hostdata->busy[tmp->target],
1106 tmp->lun);
1107 #endif
1108 /* When we find one, remove it from the issue queue. */
1109 /* ++guenther: possible race with Falcon locking */
1110 if (
1111 #ifdef SUPPORT_TAGS
1112 !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
1113 #else
1114 !(hostdata->busy[tmp->target] & (1 << tmp->lun))
1115 #endif
1116 ) {
1117 cli(); /* ++guenther: just to be sure, this must be atomic */
1118 if (prev) {
1119 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1120 NEXT(prev) = NEXT(tmp);
1121 } else {
1122 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
1123 hostdata->issue_queue = NEXT(tmp);
1124 }
1125 NEXT(tmp) = NULL;
1126 falcon_dont_release++;
1127
1128 /* reenable interrupts after finding one */
1129 restore_flags(flags);
1130
1131 /*
1132 * Attempt to establish an I_T_L nexus here.
1133 * On success, instance->hostdata->connected is set.
1134 * On failure, we must add the command back to the
1135 * issue queue so we can keep trying.
1136 */
1137 MAIN_PRINTK("scsi%d: main(): command for target %d "
1138 "lun %d removed from issue_queue\n",
1139 HOSTNO, tmp->target, tmp->lun);
1140 /*
1141 * REQUEST SENSE commands are issued without tagged
1142 * queueing, even on SCSI-II devices because the
1143 * contingent allegiance condition exists for the
1144 * entire unit.
1145 */
1146 /* ++roman: ...and the standard also requires that
1147 * REQUEST SENSE command are untagged.
1148 */
1149
1150 #ifdef SUPPORT_TAGS
1151 cmd_get_tag( tmp, tmp->cmnd[0] != REQUEST_SENSE );
1152 #endif
1153 if (!NCR5380_select(instance, tmp,
1154 (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE :
1155 TAG_NEXT)) {
1156 falcon_dont_release--;
1157 /* release if target did not response! */
1158 falcon_release_lock_if_possible( hostdata );
1159 break;
1160 } else {
1161 cli();
1162 LIST(tmp, hostdata->issue_queue);
1163 NEXT(tmp) = hostdata->issue_queue;
1164 hostdata->issue_queue = tmp;
1165 #ifdef SUPPORT_TAGS
1166 cmd_free_tag( tmp );
1167 #endif
1168 falcon_dont_release--;
1169 restore_flags(flags);
1170 MAIN_PRINTK("scsi%d: main(): select() failed, "
1171 "returned to issue_queue\n", HOSTNO);
1172 if (hostdata->connected)
1173 break;
1174 }
1175 } /* if target/lun/target queue is not busy */
1176 } /* for issue_queue */
1177 } /* if (!hostdata->connected) */
1178
1179 if (hostdata->connected
1180 #ifdef REAL_DMA
1181 && !hostdata->dma_len
1182 #endif
1183 ) {
1184 restore_flags(flags);
1185 MAIN_PRINTK("scsi%d: main: performing information transfer\n",
1186 HOSTNO);
1187 NCR5380_information_transfer(instance);
1188 MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO);
1189 done = 0;
1190 }
1191 } while (!done);
1192
1193 /* Better allow ints _after_ 'main_running' has been cleared, else
1194 an interrupt could believe we'll pick up the work it left for
1195 us, but we won't see it anymore here... */
1196 main_running = 0;
1197 restore_flags(flags);
1198 }
1199
1200
1201 #ifdef REAL_DMA
1202 /*
1203 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1204 *
1205 * Purpose : Called by interrupt handler when DMA finishes or a phase
1206 * mismatch occurs (which would finish the DMA transfer).
1207 *
1208 * Inputs : instance - this instance of the NCR5380.
1209 *
1210 */
1211
1212 static void NCR5380_dma_complete( struct Scsi_Host *instance )
1213 {
1214 SETUP_HOSTDATA(instance);
1215 int transfered, saved_data = 0, overrun = 0, cnt, toPIO;
1216 unsigned char **data, p;
1217 volatile int *count;
1218
1219 if (!hostdata->connected) {
1220 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
1221 "no connected cmd\n", HOSTNO);
1222 return;
1223 }
1224
1225 if (atari_read_overruns) {
1226 p = hostdata->connected->SCp.phase;
1227 if (p & SR_IO) {
1228 udelay(10);
1229 if ((((NCR5380_read(BUS_AND_STATUS_REG)) &
1230 (BASR_PHASE_MATCH|BASR_ACK)) ==
1231 (BASR_PHASE_MATCH|BASR_ACK))) {
1232 saved_data = NCR5380_read(INPUT_DATA_REG);
1233 overrun = 1;
1234 DMA_PRINTK("scsi%d: read overrun handled\n", HOSTNO);
1235 }
1236 }
1237 }
1238
1239 DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1240 HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
1241 NCR5380_read(STATUS_REG));
1242
1243 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1244 NCR5380_write(MODE_REG, MR_BASE);
1245 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1246
1247 transfered = hostdata->dma_len - NCR5380_dma_residual(instance);
1248 hostdata->dma_len = 0;
1249
1250 data = (unsigned char **) &(hostdata->connected->SCp.ptr);
1251 count = &(hostdata->connected->SCp.this_residual);
1252 *data += transfered;
1253 *count -= transfered;
1254
1255 if (atari_read_overruns) {
1256 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
1257 cnt = toPIO = atari_read_overruns;
1258 if (overrun) {
1259 DMA_PRINTK("Got an input overrun, using saved byte\n");
1260 *(*data)++ = saved_data;
1261 (*count)--;
1262 cnt--;
1263 toPIO--;
1264 }
1265 DMA_PRINTK("Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
1266 NCR5380_transfer_pio(instance, &p, &cnt, data);
1267 *count -= toPIO - cnt;
1268 }
1269 }
1270 }
1271 #endif /* REAL_DMA */
1272
1273
1274 /*
1275 * Function : void NCR5380_intr (int irq)
1276 *
1277 * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1278 * from the disconnected queue, and restarting NCR5380_main()
1279 * as required.
1280 *
1281 * Inputs : int irq, irq that caused this interrupt.
1282 *
1283 */
1284
1285 static void NCR5380_intr (int irq, void *dev_id, struct pt_regs *regs)
1286 {
1287 struct Scsi_Host *instance = first_instance;
1288 int done = 1;
1289 unsigned char basr;
1290
1291 INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO);
1292
1293 /* Look for pending interrupts */
1294 basr = NCR5380_read(BUS_AND_STATUS_REG);
1295 INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr);
1296 /* dispatch to appropriate routine if found and done=0 */
1297 if (basr & BASR_IRQ) {
1298 NCR_PRINT(NDEBUG_INTR);
1299 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
1300 done = 0;
1301 ENABLE_IRQ();
1302 INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO);
1303 NCR5380_reselect(instance);
1304 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1305 }
1306 else if (basr & BASR_PARITY_ERROR) {
1307 INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO);
1308 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1309 }
1310 else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1311 INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO);
1312 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1313 }
1314 else {
1315 /*
1316 * The rest of the interrupt conditions can occur only during a
1317 * DMA transfer
1318 */
1319
1320 #if defined(REAL_DMA)
1321 /*
1322 * We should only get PHASE MISMATCH and EOP interrupts if we have
1323 * DMA enabled, so do a sanity check based on the current setting
1324 * of the MODE register.
1325 */
1326
1327 if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
1328 ((basr & BASR_END_DMA_TRANSFER) ||
1329 !(basr & BASR_PHASE_MATCH))) {
1330
1331 INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1332 NCR5380_dma_complete( instance );
1333 done = 0;
1334 ENABLE_IRQ();
1335 } else
1336 #endif /* REAL_DMA */
1337 {
1338 /* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1339 if (basr & BASR_PHASE_MATCH)
1340 printk(KERN_NOTICE "scsi%d: unknown interrupt, "
1341 "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1342 HOSTNO, basr, NCR5380_read(MODE_REG),
1343 NCR5380_read(STATUS_REG));
1344 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1345 }
1346 } /* if !(SELECTION || PARITY) */
1347 } /* BASR & IRQ */
1348 else {
1349 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
1350 "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
1351 NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG));
1352 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1353 }
1354
1355 if (!done) {
1356 INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO);
1357 /* Put a call to NCR5380_main() on the queue... */
1358 queue_main();
1359 }
1360 }
1361
1362 #ifdef NCR5380_STATS
1363 static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd* cmd)
1364 {
1365 # ifdef NCR5380_STAT_LIMIT
1366 if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
1367 # endif
1368 switch (cmd->cmnd[0])
1369 {
1370 case WRITE:
1371 case WRITE_6:
1372 case WRITE_10:
1373 hostdata->time_write[cmd->target] += (jiffies - hostdata->timebase);
1374 /*hostdata->bytes_write[cmd->target] += cmd->request_bufflen;*/
1375 hostdata->pendingw--;
1376 break;
1377 case READ:
1378 case READ_6:
1379 case READ_10:
1380 hostdata->time_read[cmd->target] += (jiffies - hostdata->timebase);
1381 /*hostdata->bytes_read[cmd->target] += cmd->request_bufflen;*/
1382 hostdata->pendingr--;
1383 break;
1384 }
1385 }
1386 #endif
1387
1388 /*
1389 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1390 * int tag);
1391 *
1392 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1393 * including ARBITRATION, SELECTION, and initial message out for
1394 * IDENTIFY and queue messages.
1395 *
1396 * Inputs : instance - instantiation of the 5380 driver on which this
1397 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1398 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1399 * the command that is presently connected.
1400 *
1401 * Returns : -1 if selection could not execute for some reason,
1402 * 0 if selection succeeded or failed because the target
1403 * did not respond.
1404 *
1405 * Side effects :
1406 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1407 * with registers as they should have been on entry - ie
1408 * SELECT_ENABLE will be set appropriately, the NCR5380
1409 * will cease to drive any SCSI bus signals.
1410 *
1411 * If successful : I_T_L or I_T_L_Q nexus will be established,
1412 * instance->connected will be set to cmd.
1413 * SELECT interrupt will be disabled.
1414 *
1415 * If failed (no target) : cmd->scsi_done() will be called, and the
1416 * cmd->result host byte set to DID_BAD_TARGET.
1417 */
1418
1419 static int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag)
1420 {
1421 SETUP_HOSTDATA(instance);
1422 unsigned char tmp[3], phase;
1423 unsigned char *data;
1424 int len;
1425 unsigned long timeout;
1426 unsigned long flags;
1427
1428 hostdata->restart_select = 0;
1429 NCR_PRINT(NDEBUG_ARBITRATION);
1430 ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO,
1431 instance->this_id);
1432
1433 /*
1434 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1435 * data bus during SELECTION.
1436 */
1437
1438 save_flags(flags);
1439 cli();
1440 if (hostdata->connected) {
1441 restore_flags(flags);
1442 return -1;
1443 }
1444 NCR5380_write(TARGET_COMMAND_REG, 0);
1445
1446
1447 /*
1448 * Start arbitration.
1449 */
1450
1451 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1452 NCR5380_write(MODE_REG, MR_ARBITRATE);
1453
1454 restore_flags(flags);
1455
1456 /* Wait for arbitration logic to complete */
1457 #if NCR_TIMEOUT
1458 {
1459 unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
1460
1461 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)
1462 && time_before(jiffies, timeout) && !hostdata->connected)
1463 ;
1464 if (time_after_eq(jiffies, timeout))
1465 {
1466 printk("scsi : arbitration timeout at %d\n", __LINE__);
1467 NCR5380_write(MODE_REG, MR_BASE);
1468 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1469 return -1;
1470 }
1471 }
1472 #else /* NCR_TIMEOUT */
1473 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)
1474 && !hostdata->connected);
1475 #endif
1476
1477 ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO);
1478
1479 if (hostdata->connected) {
1480 NCR5380_write(MODE_REG, MR_BASE);
1481 return -1;
1482 }
1483 /*
1484 * The arbitration delay is 2.2us, but this is a minimum and there is
1485 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1486 * the integral nature of udelay().
1487 *
1488 */
1489
1490 udelay(3);
1491
1492 /* Check for lost arbitration */
1493 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1494 (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
1495 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1496 hostdata->connected) {
1497 NCR5380_write(MODE_REG, MR_BASE);
1498 ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1499 HOSTNO);
1500 return -1;
1501 }
1502
1503 /* after/during arbitration, BSY should be asserted.
1504 IBM DPES-31080 Version S31Q works now */
1505 /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
1506 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL |
1507 ICR_ASSERT_BSY ) ;
1508
1509 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1510 hostdata->connected) {
1511 NCR5380_write(MODE_REG, MR_BASE);
1512 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1513 ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1514 HOSTNO);
1515 return -1;
1516 }
1517
1518 /*
1519 * Again, bus clear + bus settle time is 1.2us, however, this is
1520 * a minimum so we'll udelay ceil(1.2)
1521 */
1522
1523 #ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1524 /* ++roman: But some targets (see above :-) seem to need a bit more... */
1525 udelay(15);
1526 #else
1527 udelay(2);
1528 #endif
1529
1530 if (hostdata->connected) {
1531 NCR5380_write(MODE_REG, MR_BASE);
1532 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1533 return -1;
1534 }
1535
1536 ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO);
1537
1538 /*
1539 * Now that we have won arbitration, start Selection process, asserting
1540 * the host and target ID's on the SCSI bus.
1541 */
1542
1543 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->target)));
1544
1545 /*
1546 * Raise ATN while SEL is true before BSY goes false from arbitration,
1547 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1548 * phase immediately after selection.
1549 */
1550
1551 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY |
1552 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL ));
1553 NCR5380_write(MODE_REG, MR_BASE);
1554
1555 /*
1556 * Reselect interrupts must be turned off prior to the dropping of BSY,
1557 * otherwise we will trigger an interrupt.
1558 */
1559
1560 if (hostdata->connected) {
1561 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1562 return -1;
1563 }
1564
1565 NCR5380_write(SELECT_ENABLE_REG, 0);
1566
1567 /*
1568 * The initiator shall then wait at least two deskew delays and release
1569 * the BSY signal.
1570 */
1571 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1572
1573 /* Reset BSY */
1574 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA |
1575 ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1576
1577 /*
1578 * Something weird happens when we cease to drive BSY - looks
1579 * like the board/chip is letting us do another read before the
1580 * appropriate propagation delay has expired, and we're confusing
1581 * a BSY signal from ourselves as the target's response to SELECTION.
1582 *
1583 * A small delay (the 'C++' frontend breaks the pipeline with an
1584 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1585 * tighter 'C' code breaks and requires this) solves the problem -
1586 * the 1 us delay is arbitrary, and only used because this delay will
1587 * be the same on other platforms and since it works here, it should
1588 * work there.
1589 *
1590 * wingel suggests that this could be due to failing to wait
1591 * one deskew delay.
1592 */
1593
1594 udelay(1);
1595
1596 SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->target);
1597
1598 /*
1599 * The SCSI specification calls for a 250 ms timeout for the actual
1600 * selection.
1601 */
1602
1603 timeout = jiffies + 25;
1604
1605 /*
1606 * XXX very interesting - we're seeing a bounce where the BSY we
1607 * asserted is being reflected / still asserted (propagation delay?)
1608 * and it's detecting as true. Sigh.
1609 */
1610
1611 #if 0
1612 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1613 * IO while SEL is true. But again, there are some disks out the in the
1614 * world that do that nevertheless. (Somebody claimed that this announces
1615 * reselection capability of the target.) So we better skip that test and
1616 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-)
1617 */
1618
1619 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) &
1620 (SR_BSY | SR_IO)));
1621
1622 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) ==
1623 (SR_SEL | SR_IO)) {
1624 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1625 NCR5380_reselect(instance);
1626 printk (KERN_ERR "scsi%d: reselection after won arbitration?\n",
1627 HOSTNO);
1628 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1629 return -1;
1630 }
1631 #else
1632 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY));
1633 #endif
1634
1635 /*
1636 * No less than two deskew delays after the initiator detects the
1637 * BSY signal is true, it shall release the SEL signal and may
1638 * change the DATA BUS. -wingel
1639 */
1640
1641 udelay(1);
1642
1643 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1644
1645 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1646 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1647 if (hostdata->targets_present & (1 << cmd->target)) {
1648 printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO);
1649 if (hostdata->restart_select)
1650 printk(KERN_NOTICE "\trestart select\n");
1651 NCR_PRINT(NDEBUG_ANY);
1652 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1653 return -1;
1654 }
1655 cmd->result = DID_BAD_TARGET << 16;
1656 #ifdef NCR5380_STATS
1657 collect_stats(hostdata, cmd);
1658 #endif
1659 #ifdef SUPPORT_TAGS
1660 cmd_free_tag( cmd );
1661 #endif
1662 cmd->scsi_done(cmd);
1663 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1664 SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO);
1665 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1666 return 0;
1667 }
1668
1669 hostdata->targets_present |= (1 << cmd->target);
1670
1671 /*
1672 * Since we followed the SCSI spec, and raised ATN while SEL
1673 * was true but before BSY was false during selection, the information
1674 * transfer phase should be a MESSAGE OUT phase so that we can send the
1675 * IDENTIFY message.
1676 *
1677 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1678 * message (2 bytes) with a tag ID that we increment with every command
1679 * until it wraps back to 0.
1680 *
1681 * XXX - it turns out that there are some broken SCSI-II devices,
1682 * which claim to support tagged queuing but fail when more than
1683 * some number of commands are issued at once.
1684 */
1685
1686 /* Wait for start of REQ/ACK handshake */
1687 while (!(NCR5380_read(STATUS_REG) & SR_REQ));
1688
1689 SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1690 HOSTNO, cmd->target);
1691 tmp[0] = IDENTIFY(1, cmd->lun);
1692
1693 #ifdef SUPPORT_TAGS
1694 if (cmd->tag != TAG_NONE) {
1695 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
1696 tmp[2] = cmd->tag;
1697 len = 3;
1698 } else
1699 len = 1;
1700 #else
1701 len = 1;
1702 cmd->tag=0;
1703 #endif /* SUPPORT_TAGS */
1704
1705 /* Send message(s) */
1706 data = tmp;
1707 phase = PHASE_MSGOUT;
1708 NCR5380_transfer_pio(instance, &phase, &len, &data);
1709 SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO);
1710 /* XXX need to handle errors here */
1711 hostdata->connected = cmd;
1712 #ifndef SUPPORT_TAGS
1713 hostdata->busy[cmd->target] |= (1 << cmd->lun);
1714 #endif
1715
1716 initialize_SCp(cmd);
1717
1718
1719 return 0;
1720 }
1721
1722 /*
1723 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1724 * unsigned char *phase, int *count, unsigned char **data)
1725 *
1726 * Purpose : transfers data in given phase using polled I/O
1727 *
1728 * Inputs : instance - instance of driver, *phase - pointer to
1729 * what phase is expected, *count - pointer to number of
1730 * bytes to transfer, **data - pointer to data pointer.
1731 *
1732 * Returns : -1 when different phase is entered without transferring
1733 * maximum number of bytes, 0 if all bytes are transfered or exit
1734 * is in same phase.
1735 *
1736 * Also, *phase, *count, *data are modified in place.
1737 *
1738 * XXX Note : handling for bus free may be useful.
1739 */
1740
1741 /*
1742 * Note : this code is not as quick as it could be, however it
1743 * IS 100% reliable, and for the actual data transfer where speed
1744 * counts, we will always do a pseudo DMA or DMA transfer.
1745 */
1746
1747 static int NCR5380_transfer_pio( struct Scsi_Host *instance,
1748 unsigned char *phase, int *count,
1749 unsigned char **data)
1750 {
1751 register unsigned char p = *phase, tmp;
1752 register int c = *count;
1753 register unsigned char *d = *data;
1754
1755 /*
1756 * The NCR5380 chip will only drive the SCSI bus when the
1757 * phase specified in the appropriate bits of the TARGET COMMAND
1758 * REGISTER match the STATUS REGISTER
1759 */
1760
1761 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1762
1763 do {
1764 /*
1765 * Wait for assertion of REQ, after which the phase bits will be
1766 * valid
1767 */
1768 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ));
1769
1770 HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO);
1771
1772 /* Check for phase mismatch */
1773 if ((tmp & PHASE_MASK) != p) {
1774 PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO);
1775 NCR_PRINT_PHASE(NDEBUG_PIO);
1776 break;
1777 }
1778
1779 /* Do actual transfer from SCSI bus to / from memory */
1780 if (!(p & SR_IO))
1781 NCR5380_write(OUTPUT_DATA_REG, *d);
1782 else
1783 *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1784
1785 ++d;
1786
1787 /*
1788 * The SCSI standard suggests that in MSGOUT phase, the initiator
1789 * should drop ATN on the last byte of the message phase
1790 * after REQ has been asserted for the handshake but before
1791 * the initiator raises ACK.
1792 */
1793
1794 if (!(p & SR_IO)) {
1795 if (!((p & SR_MSG) && c > 1)) {
1796 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1797 ICR_ASSERT_DATA);
1798 NCR_PRINT(NDEBUG_PIO);
1799 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1800 ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1801 } else {
1802 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1803 ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1804 NCR_PRINT(NDEBUG_PIO);
1805 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1806 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1807 }
1808 } else {
1809 NCR_PRINT(NDEBUG_PIO);
1810 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1811 }
1812
1813 while (NCR5380_read(STATUS_REG) & SR_REQ);
1814
1815 HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO);
1816
1817 /*
1818 * We have several special cases to consider during REQ/ACK handshaking :
1819 * 1. We were in MSGOUT phase, and we are on the last byte of the
1820 * message. ATN must be dropped as ACK is dropped.
1821 *
1822 * 2. We are in a MSGIN phase, and we are on the last byte of the
1823 * message. We must exit with ACK asserted, so that the calling
1824 * code may raise ATN before dropping ACK to reject the message.
1825 *
1826 * 3. ACK and ATN are clear and the target may proceed as normal.
1827 */
1828 if (!(p == PHASE_MSGIN && c == 1)) {
1829 if (p == PHASE_MSGOUT && c > 1)
1830 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1831 else
1832 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1833 }
1834 } while (--c);
1835
1836 PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c);
1837
1838 *count = c;
1839 *data = d;
1840 tmp = NCR5380_read(STATUS_REG);
1841 /* The phase read from the bus is valid if either REQ is (already)
1842 * asserted or if ACK hasn't been released yet. The latter is the case if
1843 * we're in MSGIN and all wanted bytes have been received. */
1844 if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
1845 *phase = tmp & PHASE_MASK;
1846 else
1847 *phase = PHASE_UNKNOWN;
1848
1849 if (!c || (*phase == p))
1850 return 0;
1851 else
1852 return -1;
1853 }
1854
1855 /*
1856 * Function : do_abort (Scsi_Host *host)
1857 *
1858 * Purpose : abort the currently established nexus. Should only be
1859 * called from a routine which can drop into a
1860 *
1861 * Returns : 0 on success, -1 on failure.
1862 */
1863
1864 static int do_abort (struct Scsi_Host *host)
1865 {
1866 unsigned char tmp, *msgptr, phase;
1867 int len;
1868
1869 /* Request message out phase */
1870 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1871
1872 /*
1873 * Wait for the target to indicate a valid phase by asserting
1874 * REQ. Once this happens, we'll have either a MSGOUT phase
1875 * and can immediately send the ABORT message, or we'll have some
1876 * other phase and will have to source/sink data.
1877 *
1878 * We really don't care what value was on the bus or what value
1879 * the target sees, so we just handshake.
1880 */
1881
1882 while (!(tmp = NCR5380_read(STATUS_REG)) & SR_REQ);
1883
1884 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1885
1886 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1887 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
1888 ICR_ASSERT_ACK);
1889 while (NCR5380_read(STATUS_REG) & SR_REQ);
1890 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1891 }
1892
1893 tmp = ABORT;
1894 msgptr = &tmp;
1895 len = 1;
1896 phase = PHASE_MSGOUT;
1897 NCR5380_transfer_pio (host, &phase, &len, &msgptr);
1898
1899 /*
1900 * If we got here, and the command completed successfully,
1901 * we're about to go into bus free state.
1902 */
1903
1904 return len ? -1 : 0;
1905 }
1906
1907 #if defined(REAL_DMA)
1908 /*
1909 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1910 * unsigned char *phase, int *count, unsigned char **data)
1911 *
1912 * Purpose : transfers data in given phase using either real
1913 * or pseudo DMA.
1914 *
1915 * Inputs : instance - instance of driver, *phase - pointer to
1916 * what phase is expected, *count - pointer to number of
1917 * bytes to transfer, **data - pointer to data pointer.
1918 *
1919 * Returns : -1 when different phase is entered without transferring
1920 * maximum number of bytes, 0 if all bytes or transfered or exit
1921 * is in same phase.
1922 *
1923 * Also, *phase, *count, *data are modified in place.
1924 *
1925 */
1926
1927
1928 static int NCR5380_transfer_dma( struct Scsi_Host *instance,
1929 unsigned char *phase, int *count,
1930 unsigned char **data)
1931 {
1932 SETUP_HOSTDATA(instance);
1933 register int c = *count;
1934 register unsigned char p = *phase;
1935 register unsigned char *d = *data;
1936 unsigned char tmp;
1937 unsigned long flags;
1938
1939 if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1940 *phase = tmp;
1941 return -1;
1942 }
1943
1944 if (atari_read_overruns && (p & SR_IO)) {
1945 c -= atari_read_overruns;
1946 }
1947
1948 DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1949 HOSTNO, (p & SR_IO) ? "reading" : "writing",
1950 c, (p & SR_IO) ? "to" : "from", d);
1951
1952 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1953
1954 #ifdef REAL_DMA
1955 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1956 #endif /* def REAL_DMA */
1957
1958 if (IS_A_TT()) {
1959 /* On the Medusa, it is a must to initialize the DMA before
1960 * starting the NCR. This is also the cleaner way for the TT.
1961 */
1962 save_flags(flags);
1963 cli();
1964 hostdata->dma_len = (p & SR_IO) ?
1965 NCR5380_dma_read_setup(instance, d, c) :
1966 NCR5380_dma_write_setup(instance, d, c);
1967 restore_flags(flags);
1968 }
1969
1970 if (p & SR_IO)
1971 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1972 else {
1973 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1974 NCR5380_write(START_DMA_SEND_REG, 0);
1975 }
1976
1977 if (!IS_A_TT()) {
1978 /* On the Falcon, the DMA setup must be done after the last */
1979 /* NCR access, else the DMA setup gets trashed!
1980 */
1981 save_flags(flags);
1982 cli();
1983 hostdata->dma_len = (p & SR_IO) ?
1984 NCR5380_dma_read_setup(instance, d, c) :
1985 NCR5380_dma_write_setup(instance, d, c);
1986 restore_flags(flags);
1987 }
1988 return 0;
1989 }
1990 #endif /* defined(REAL_DMA) */
1991
1992 /*
1993 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1994 *
1995 * Purpose : run through the various SCSI phases and do as the target
1996 * directs us to. Operates on the currently connected command,
1997 * instance->connected.
1998 *
1999 * Inputs : instance, instance for which we are doing commands
2000 *
2001 * Side effects : SCSI things happen, the disconnected queue will be
2002 * modified if a command disconnects, *instance->connected will
2003 * change.
2004 *
2005 * XXX Note : we need to watch for bus free or a reset condition here
2006 * to recover from an unexpected bus free condition.
2007 */
2008
2009 static void NCR5380_information_transfer (struct Scsi_Host *instance)
2010 {
2011 SETUP_HOSTDATA(instance);
2012 unsigned long flags;
2013 unsigned char msgout = NOP;
2014 int sink = 0;
2015 int len;
2016 #if defined(REAL_DMA)
2017 int transfersize;
2018 #endif
2019 unsigned char *data;
2020 unsigned char phase, tmp, extended_msg[10], old_phase=0xff;
2021 Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2022
2023 while (1) {
2024 tmp = NCR5380_read(STATUS_REG);
2025 /* We only have a valid SCSI phase when REQ is asserted */
2026 if (tmp & SR_REQ) {
2027 phase = (tmp & PHASE_MASK);
2028 if (phase != old_phase) {
2029 old_phase = phase;
2030 NCR_PRINT_PHASE(NDEBUG_INFORMATION);
2031 }
2032
2033 if (sink && (phase != PHASE_MSGOUT)) {
2034 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2035
2036 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
2037 ICR_ASSERT_ACK);
2038 while (NCR5380_read(STATUS_REG) & SR_REQ);
2039 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2040 ICR_ASSERT_ATN);
2041 sink = 0;
2042 continue;
2043 }
2044
2045 switch (phase) {
2046 case PHASE_DATAOUT:
2047 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2048 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2049 "aborted\n", HOSTNO);
2050 sink = 1;
2051 do_abort(instance);
2052 cmd->result = DID_ERROR << 16;
2053 cmd->done(cmd);
2054 return;
2055 #endif
2056 case PHASE_DATAIN:
2057 /*
2058 * If there is no room left in the current buffer in the
2059 * scatter-gather list, move onto the next one.
2060 */
2061
2062 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2063 ++cmd->SCp.buffer;
2064 --cmd->SCp.buffers_residual;
2065 cmd->SCp.this_residual = cmd->SCp.buffer->length;
2066 cmd->SCp.ptr = cmd->SCp.buffer->address;
2067 /* ++roman: Try to merge some scatter-buffers if
2068 * they are at contiguous physical addresses.
2069 */
2070 merge_contiguous_buffers( cmd );
2071 INF_PRINTK("scsi%d: %d bytes and %d buffers left\n",
2072 HOSTNO, cmd->SCp.this_residual,
2073 cmd->SCp.buffers_residual);
2074 }
2075
2076 /*
2077 * The preferred transfer method is going to be
2078 * PSEUDO-DMA for systems that are strictly PIO,
2079 * since we can let the hardware do the handshaking.
2080 *
2081 * For this to work, we need to know the transfersize
2082 * ahead of time, since the pseudo-DMA code will sit
2083 * in an unconditional loop.
2084 */
2085
2086 /* ++roman: I suggest, this should be
2087 * #if def(REAL_DMA)
2088 * instead of leaving REAL_DMA out.
2089 */
2090
2091 #if defined(REAL_DMA)
2092 if (!cmd->device->borken &&
2093 (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) {
2094 len = transfersize;
2095 cmd->SCp.phase = phase;
2096 if (NCR5380_transfer_dma(instance, &phase,
2097 &len, (unsigned char **) &cmd->SCp.ptr)) {
2098 /*
2099 * If the watchdog timer fires, all future
2100 * accesses to this device will use the
2101 * polled-IO. */
2102 printk(KERN_NOTICE "scsi%d: switching target %d "
2103 "lun %d to slow handshake\n", HOSTNO,
2104 cmd->target, cmd->lun);
2105 cmd->device->borken = 1;
2106 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2107 ICR_ASSERT_ATN);
2108 sink = 1;
2109 do_abort(instance);
2110 cmd->result = DID_ERROR << 16;
2111 cmd->done(cmd);
2112 /* XXX - need to source or sink data here, as appropriate */
2113 } else {
2114 #ifdef REAL_DMA
2115 /* ++roman: When using real DMA,
2116 * information_transfer() should return after
2117 * starting DMA since it has nothing more to
2118 * do.
2119 */
2120 return;
2121 #else
2122 cmd->SCp.this_residual -= transfersize - len;
2123 #endif
2124 }
2125 } else
2126 #endif /* defined(REAL_DMA) */
2127 NCR5380_transfer_pio(instance, &phase,
2128 (int *) &cmd->SCp.this_residual, (unsigned char **)
2129 &cmd->SCp.ptr);
2130 break;
2131 case PHASE_MSGIN:
2132 len = 1;
2133 data = &tmp;
2134 NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */
2135 NCR5380_transfer_pio(instance, &phase, &len, &data);
2136 cmd->SCp.Message = tmp;
2137
2138 switch (tmp) {
2139 /*
2140 * Linking lets us reduce the time required to get the
2141 * next command out to the device, hopefully this will
2142 * mean we don't waste another revolution due to the delays
2143 * required by ARBITRATION and another SELECTION.
2144 *
2145 * In the current implementation proposal, low level drivers
2146 * merely have to start the next command, pointed to by
2147 * next_link, done() is called as with unlinked commands.
2148 */
2149 #ifdef LINKED
2150 case LINKED_CMD_COMPLETE:
2151 case LINKED_FLG_CMD_COMPLETE:
2152 /* Accept message by clearing ACK */
2153 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2154
2155 LNK_PRINTK("scsi%d: target %d lun %d linked command "
2156 "complete.\n", HOSTNO, cmd->target, cmd->lun);
2157
2158 /* Enable reselect interrupts */
2159 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2160 /*
2161 * Sanity check : A linked command should only terminate
2162 * with one of these messages if there are more linked
2163 * commands available.
2164 */
2165
2166 if (!cmd->next_link) {
2167 printk(KERN_NOTICE "scsi%d: target %d lun %d "
2168 "linked command complete, no next_link\n",
2169 HOSTNO, cmd->target, cmd->lun);
2170 sink = 1;
2171 do_abort (instance);
2172 return;
2173 }
2174
2175 initialize_SCp(cmd->next_link);
2176 /* The next command is still part of this process; copy it
2177 * and don't free it! */
2178 cmd->next_link->tag = cmd->tag;
2179 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2180 LNK_PRINTK("scsi%d: target %d lun %d linked request "
2181 "done, calling scsi_done().\n",
2182 HOSTNO, cmd->target, cmd->lun);
2183 #ifdef NCR5380_STATS
2184 collect_stats(hostdata, cmd);
2185 #endif
2186 cmd->scsi_done(cmd);
2187 cmd = hostdata->connected;
2188 break;
2189 #endif /* def LINKED */
2190 case ABORT:
2191 case COMMAND_COMPLETE:
2192 /* Accept message by clearing ACK */
2193 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2194 /* ++guenther: possible race with Falcon locking */
2195 falcon_dont_release++;
2196 hostdata->connected = NULL;
2197 QU_PRINTK("scsi%d: command for target %d, lun %d "
2198 "completed\n", HOSTNO, cmd->target, cmd->lun);
2199 #ifdef SUPPORT_TAGS
2200 cmd_free_tag( cmd );
2201 if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
2202 /* Turn a QUEUE FULL status into BUSY, I think the
2203 * mid level cannot handle QUEUE FULL :-( (The
2204 * command is retried after BUSY). Also update our
2205 * queue size to the number of currently issued
2206 * commands now.
2207 */
2208 /* ++Andreas: the mid level code knows about
2209 QUEUE_FULL now. */
2210 TAG_ALLOC *ta = &TagAlloc[cmd->target][cmd->lun];
2211 TAG_PRINTK("scsi%d: target %d lun %d returned "
2212 "QUEUE_FULL after %d commands\n",
2213 HOSTNO, cmd->target, cmd->lun,
2214 ta->nr_allocated);
2215 if (ta->queue_size > ta->nr_allocated)
2216 ta->nr_allocated = ta->queue_size;
2217 }
2218 #else
2219 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
2220 #endif
2221 /* Enable reselect interrupts */
2222 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2223
2224 /*
2225 * I'm not sure what the correct thing to do here is :
2226 *
2227 * If the command that just executed is NOT a request
2228 * sense, the obvious thing to do is to set the result
2229 * code to the values of the stored parameters.
2230 *
2231 * If it was a REQUEST SENSE command, we need some way to
2232 * differentiate between the failure code of the original
2233 * and the failure code of the REQUEST sense - the obvious
2234 * case is success, where we fall through and leave the
2235 * result code unchanged.
2236 *
2237 * The non-obvious place is where the REQUEST SENSE failed
2238 */
2239
2240 if (cmd->cmnd[0] != REQUEST_SENSE)
2241 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2242 else if (status_byte(cmd->SCp.Status) != GOOD)
2243 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2244
2245 #ifdef AUTOSENSE
2246 if ((cmd->cmnd[0] != REQUEST_SENSE) &&
2247 (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2248 ASEN_PRINTK("scsi%d: performing request sense\n",
2249 HOSTNO);
2250 cmd->cmnd[0] = REQUEST_SENSE;
2251 cmd->cmnd[1] &= 0xe0;
2252 cmd->cmnd[2] = 0;
2253 cmd->cmnd[3] = 0;
2254 cmd->cmnd[4] = sizeof(cmd->sense_buffer);
2255 cmd->cmnd[5] = 0;
2256 cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]);
2257
2258 cmd->use_sg = 0;
2259 /* this is initialized from initialize_SCp
2260 cmd->SCp.buffer = NULL;
2261 cmd->SCp.buffers_residual = 0;
2262 */
2263 cmd->request_buffer = (char *) cmd->sense_buffer;
2264 cmd->request_bufflen = sizeof(cmd->sense_buffer);
2265
2266 save_flags(flags);
2267 cli();
2268 LIST(cmd,hostdata->issue_queue);
2269 NEXT(cmd) = hostdata->issue_queue;
2270 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2271 restore_flags(flags);
2272 QU_PRINTK("scsi%d: REQUEST SENSE added to head of "
2273 "issue queue\n", H_NO(cmd));
2274 } else
2275 #endif /* def AUTOSENSE */
2276 {
2277 #ifdef NCR5380_STATS
2278 collect_stats(hostdata, cmd);
2279 #endif
2280 cmd->scsi_done(cmd);
2281 }
2282
2283 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2284 /*
2285 * Restore phase bits to 0 so an interrupted selection,
2286 * arbitration can resume.
2287 */
2288 NCR5380_write(TARGET_COMMAND_REG, 0);
2289
2290 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2291 barrier();
2292
2293 falcon_dont_release--;
2294 /* ++roman: For Falcon SCSI, release the lock on the
2295 * ST-DMA here if no other commands are waiting on the
2296 * disconnected queue.
2297 */
2298 falcon_release_lock_if_possible( hostdata );
2299 return;
2300 case MESSAGE_REJECT:
2301 /* Accept message by clearing ACK */
2302 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2303 /* Enable reselect interrupts */
2304 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2305 switch (hostdata->last_message) {
2306 case HEAD_OF_QUEUE_TAG:
2307 case ORDERED_QUEUE_TAG:
2308 case SIMPLE_QUEUE_TAG:
2309 /* The target obviously doesn't support tagged
2310 * queuing, even though it announced this ability in
2311 * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2312 * clear 'tagged_supported' and lock the LUN, since
2313 * the command is treated as untagged further on.
2314 */
2315 cmd->device->tagged_supported = 0;
2316 hostdata->busy[cmd->target] |= (1 << cmd->lun);
2317 cmd->tag = TAG_NONE;
2318 TAG_PRINTK("scsi%d: target %d lun %d rejected "
2319 "QUEUE_TAG message; tagged queuing "
2320 "disabled\n",
2321 HOSTNO, cmd->target, cmd->lun);
2322 break;
2323 }
2324 break;
2325 case DISCONNECT:
2326 /* Accept message by clearing ACK */
2327 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2328 save_flags(flags);
2329 cli();
2330 cmd->device->disconnect = 1;
2331 LIST(cmd,hostdata->disconnected_queue);
2332 NEXT(cmd) = hostdata->disconnected_queue;
2333 hostdata->connected = NULL;
2334 hostdata->disconnected_queue = cmd;
2335 restore_flags(flags);
2336 QU_PRINTK("scsi%d: command for target %d lun %d was "
2337 "moved from connected to the "
2338 "disconnected_queue\n", HOSTNO,
2339 cmd->target, cmd->lun);
2340 /*
2341 * Restore phase bits to 0 so an interrupted selection,
2342 * arbitration can resume.
2343 */
2344 NCR5380_write(TARGET_COMMAND_REG, 0);
2345
2346 /* Enable reselect interrupts */
2347 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2348 /* Wait for bus free to avoid nasty timeouts */
2349 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2350 barrier();
2351 return;
2352 /*
2353 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2354 * operation, in violation of the SCSI spec so we can safely
2355 * ignore SAVE/RESTORE pointers calls.
2356 *
2357 * Unfortunately, some disks violate the SCSI spec and
2358 * don't issue the required SAVE_POINTERS message before
2359 * disconnecting, and we have to break spec to remain
2360 * compatible.
2361 */
2362 case SAVE_POINTERS:
2363 case RESTORE_POINTERS:
2364 /* Accept message by clearing ACK */
2365 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2366 /* Enable reselect interrupts */
2367 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2368 break;
2369 case EXTENDED_MESSAGE:
2370 /*
2371 * Extended messages are sent in the following format :
2372 * Byte
2373 * 0 EXTENDED_MESSAGE == 1
2374 * 1 length (includes one byte for code, doesn't
2375 * include first two bytes)
2376 * 2 code
2377 * 3..length+1 arguments
2378 *
2379 * Start the extended message buffer with the EXTENDED_MESSAGE
2380 * byte, since print_msg() wants the whole thing.
2381 */
2382 extended_msg[0] = EXTENDED_MESSAGE;
2383 /* Accept first byte by clearing ACK */
2384 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2385
2386 EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO);
2387
2388 len = 2;
2389 data = extended_msg + 1;
2390 phase = PHASE_MSGIN;
2391 NCR5380_transfer_pio(instance, &phase, &len, &data);
2392 EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2393 (int)extended_msg[1], (int)extended_msg[2]);
2394
2395 if (!len && extended_msg[1] <=
2396 (sizeof (extended_msg) - 1)) {
2397 /* Accept third byte by clearing ACK */
2398 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2399 len = extended_msg[1] - 1;
2400 data = extended_msg + 3;
2401 phase = PHASE_MSGIN;
2402
2403 NCR5380_transfer_pio(instance, &phase, &len, &data);
2404 EXT_PRINTK("scsi%d: message received, residual %d\n",
2405 HOSTNO, len);
2406
2407 switch (extended_msg[2]) {
2408 case EXTENDED_SDTR:
2409 case EXTENDED_WDTR:
2410 case EXTENDED_MODIFY_DATA_POINTER:
2411 case EXTENDED_EXTENDED_IDENTIFY:
2412 tmp = 0;
2413 }
2414 } else if (len) {
2415 printk(KERN_NOTICE "scsi%d: error receiving "
2416 "extended message\n", HOSTNO);
2417 tmp = 0;
2418 } else {
2419 printk(KERN_NOTICE "scsi%d: extended message "
2420 "code %02x length %d is too long\n",
2421 HOSTNO, extended_msg[2], extended_msg[1]);
2422 tmp = 0;
2423 }
2424 /* Fall through to reject message */
2425
2426 /*
2427 * If we get something weird that we aren't expecting,
2428 * reject it.
2429 */
2430 default:
2431 if (!tmp) {
2432 printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO);
2433 print_msg (extended_msg);
2434 printk("\n");
2435 } else if (tmp != EXTENDED_MESSAGE)
2436 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2437 "message %02x from target %d, lun %d\n",
2438 HOSTNO, tmp, cmd->target, cmd->lun);
2439 else
2440 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2441 "extended message "
2442 "code %02x, length %d from target %d, lun %d\n",
2443 HOSTNO, extended_msg[1], extended_msg[0],
2444 cmd->target, cmd->lun);
2445
2446
2447 msgout = MESSAGE_REJECT;
2448 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2449 ICR_ASSERT_ATN);
2450 break;
2451 } /* switch (tmp) */
2452 break;
2453 case PHASE_MSGOUT:
2454 len = 1;
2455 data = &msgout;
2456 hostdata->last_message = msgout;
2457 NCR5380_transfer_pio(instance, &phase, &len, &data);
2458 if (msgout == ABORT) {
2459 #ifdef SUPPORT_TAGS
2460 cmd_free_tag( cmd );
2461 #else
2462 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
2463 #endif
2464 hostdata->connected = NULL;
2465 cmd->result = DID_ERROR << 16;
2466 #ifdef NCR5380_STATS
2467 collect_stats(hostdata, cmd);
2468 #endif
2469 cmd->scsi_done(cmd);
2470 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2471 falcon_release_lock_if_possible( hostdata );
2472 return;
2473 }
2474 msgout = NOP;
2475 break;
2476 case PHASE_CMDOUT:
2477 len = cmd->cmd_len;
2478 data = cmd->cmnd;
2479 /*
2480 * XXX for performance reasons, on machines with a
2481 * PSEUDO-DMA architecture we should probably
2482 * use the dma transfer function.
2483 */
2484 NCR5380_transfer_pio(instance, &phase, &len,
2485 &data);
2486 break;
2487 case PHASE_STATIN:
2488 len = 1;
2489 data = &tmp;
2490 NCR5380_transfer_pio(instance, &phase, &len, &data);
2491 cmd->SCp.Status = tmp;
2492 break;
2493 default:
2494 printk("scsi%d: unknown phase\n", HOSTNO);
2495 NCR_PRINT(NDEBUG_ANY);
2496 } /* switch(phase) */
2497 } /* if (tmp * SR_REQ) */
2498 } /* while (1) */
2499 }
2500
2501 /*
2502 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2503 *
2504 * Purpose : does reselection, initializing the instance->connected
2505 * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2506 * nexus has been reestablished,
2507 *
2508 * Inputs : instance - this instance of the NCR5380.
2509 *
2510 */
2511
2512
2513 static void NCR5380_reselect (struct Scsi_Host *instance)
2514 {
2515 SETUP_HOSTDATA(instance);
2516 unsigned char target_mask;
2517 unsigned char lun, phase;
2518 int len;
2519 #ifdef SUPPORT_TAGS
2520 unsigned char tag;
2521 #endif
2522 unsigned char msg[3];
2523 unsigned char *data;
2524 Scsi_Cmnd *tmp = NULL, *prev;
2525 /* unsigned long flags; */
2526
2527 /*
2528 * Disable arbitration, etc. since the host adapter obviously
2529 * lost, and tell an interrupted NCR5380_select() to restart.
2530 */
2531
2532 NCR5380_write(MODE_REG, MR_BASE);
2533 hostdata->restart_select = 1;
2534
2535 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2536
2537 RSL_PRINTK("scsi%d: reselect\n", HOSTNO);
2538
2539 /*
2540 * At this point, we have detected that our SCSI ID is on the bus,
2541 * SEL is true and BSY was false for at least one bus settle delay
2542 * (400 ns).
2543 *
2544 * We must assert BSY ourselves, until the target drops the SEL
2545 * signal.
2546 */
2547
2548 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2549
2550 while (NCR5380_read(STATUS_REG) & SR_SEL);
2551 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2552
2553 /*
2554 * Wait for target to go into MSGIN.
2555 */
2556
2557 while (!(NCR5380_read(STATUS_REG) & SR_REQ));
2558
2559 len = 1;
2560 data = msg;
2561 phase = PHASE_MSGIN;
2562 NCR5380_transfer_pio(instance, &phase, &len, &data);
2563
2564 if (!msg[0] & 0x80) {
2565 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
2566 print_msg(msg);
2567 do_abort(instance);
2568 return;
2569 }
2570 lun = (msg[0] & 0x07);
2571
2572 #ifdef SUPPORT_TAGS
2573 /* If the phase is still MSGIN, the target wants to send some more
2574 * messages. In case it supports tagged queuing, this is probably a
2575 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2576 */
2577 tag = TAG_NONE;
2578 if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
2579 /* Accept previous IDENTIFY message by clearing ACK */
2580 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE );
2581 len = 2;
2582 data = msg+1;
2583 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2584 msg[1] == SIMPLE_QUEUE_TAG)
2585 tag = msg[2];
2586 TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at "
2587 "reselection\n", HOSTNO, target_mask, lun, tag);
2588 }
2589 #endif
2590
2591 /*
2592 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2593 * just reestablished, and remove it from the disconnected queue.
2594 */
2595
2596 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL;
2597 tmp; prev = tmp, tmp = NEXT(tmp) ) {
2598 if ((target_mask == (1 << tmp->target)) && (lun == tmp->lun)
2599 #ifdef SUPPORT_TAGS
2600 && (tag == tmp->tag)
2601 #endif
2602 ) {
2603 /* ++guenther: prevent race with falcon_release_lock */
2604 falcon_dont_release++;
2605 if (prev) {
2606 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2607 NEXT(prev) = NEXT(tmp);
2608 } else {
2609 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
2610 hostdata->disconnected_queue = NEXT(tmp);
2611 }
2612 NEXT(tmp) = NULL;
2613 break;
2614 }
2615 }
2616
2617 if (!tmp) {
2618 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
2619 #ifdef SUPPORT_TAGS
2620 "tag %d "
2621 #endif
2622 "not in disconnected_queue.\n",
2623 HOSTNO, target_mask, lun
2624 #ifdef SUPPORT_TAGS
2625 , tag
2626 #endif
2627 );
2628 /*
2629 * Since we have an established nexus that we can't do anything
2630 * with, we must abort it.
2631 */
2632 do_abort(instance);
2633 return;
2634 }
2635
2636 /* Accept message by clearing ACK */
2637 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2638
2639 hostdata->connected = tmp;
2640 RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n",
2641 HOSTNO, tmp->target, tmp->lun, tmp->tag);
2642 falcon_dont_release--;
2643 }
2644
2645
2646 /*
2647 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2648 *
2649 * Purpose : abort a command
2650 *
2651 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2652 * host byte of the result field to, if zero DID_ABORTED is
2653 * used.
2654 *
2655 * Returns : 0 - success, -1 on failure.
2656 *
2657 * XXX - there is no way to abort the command that is currently
2658 * connected, you have to wait for it to complete. If this is
2659 * a problem, we could implement longjmp() / setjmp(), setjmp()
2660 * called where the loop started in NCR5380_main().
2661 */
2662
2663 #ifndef NCR5380_abort
2664 static
2665 #endif
2666 int NCR5380_abort (Scsi_Cmnd *cmd)
2667 {
2668 struct Scsi_Host *instance = cmd->host;
2669 SETUP_HOSTDATA(instance);
2670 Scsi_Cmnd *tmp, **prev;
2671 unsigned long flags;
2672
2673 printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO);
2674 print_Scsi_Cmnd (cmd);
2675
2676 NCR5380_print_status (instance);
2677
2678 save_flags(flags);
2679 cli();
2680
2681 if (!IS_A_TT() && !falcon_got_lock)
2682 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n",
2683 HOSTNO);
2684
2685 ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2686 NCR5380_read(BUS_AND_STATUS_REG),
2687 NCR5380_read(STATUS_REG));
2688
2689 #if 1
2690 /*
2691 * Case 1 : If the command is the currently executing command,
2692 * we'll set the aborted flag and return control so that
2693 * information transfer routine can exit cleanly.
2694 */
2695
2696 if (hostdata->connected == cmd) {
2697
2698 ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO);
2699 /*
2700 * We should perform BSY checking, and make sure we haven't slipped
2701 * into BUS FREE.
2702 */
2703
2704 /* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2705 /*
2706 * Since we can't change phases until we've completed the current
2707 * handshake, we have to source or sink a byte of data if the current
2708 * phase is not MSGOUT.
2709 */
2710
2711 /*
2712 * Return control to the executing NCR drive so we can clear the
2713 * aborted flag and get back into our main loop.
2714 */
2715
2716 if (do_abort(instance) == 0) {
2717 hostdata->aborted = 1;
2718 hostdata->connected = NULL;
2719 cmd->result = DID_ABORT << 16;
2720 #ifdef SUPPORT_TAGS
2721 cmd_free_tag( cmd );
2722 #else
2723 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
2724 #endif
2725 restore_flags(flags);
2726 cmd->scsi_done(cmd);
2727 falcon_release_lock_if_possible( hostdata );
2728 return SCSI_ABORT_SUCCESS;
2729 } else {
2730 /* restore_flags(flags); */
2731 printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2732 return SCSI_ABORT_ERROR;
2733 }
2734 }
2735 #endif
2736
2737 /*
2738 * Case 2 : If the command hasn't been issued yet, we simply remove it
2739 * from the issue queue.
2740 */
2741 for (prev = (Scsi_Cmnd **) &(hostdata->issue_queue),
2742 tmp = (Scsi_Cmnd *) hostdata->issue_queue;
2743 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) )
2744 if (cmd == tmp) {
2745 REMOVE(5, *prev, tmp, NEXT(tmp));
2746 (*prev) = NEXT(tmp);
2747 NEXT(tmp) = NULL;
2748 tmp->result = DID_ABORT << 16;
2749 restore_flags(flags);
2750 ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n",
2751 HOSTNO);
2752 /* Tagged queuing note: no tag to free here, hasn't been assigned
2753 * yet... */
2754 tmp->scsi_done(tmp);
2755 falcon_release_lock_if_possible( hostdata );
2756 return SCSI_ABORT_SUCCESS;
2757 }
2758
2759 /*
2760 * Case 3 : If any commands are connected, we're going to fail the abort
2761 * and let the high level SCSI driver retry at a later time or
2762 * issue a reset.
2763 *
2764 * Timeouts, and therefore aborted commands, will be highly unlikely
2765 * and handling them cleanly in this situation would make the common
2766 * case of noresets less efficient, and would pollute our code. So,
2767 * we fail.
2768 */
2769
2770 if (hostdata->connected) {
2771 restore_flags(flags);
2772 ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO);
2773 return SCSI_ABORT_SNOOZE;
2774 }
2775
2776 /*
2777 * Case 4: If the command is currently disconnected from the bus, and
2778 * there are no connected commands, we reconnect the I_T_L or
2779 * I_T_L_Q nexus associated with it, go into message out, and send
2780 * an abort message.
2781 *
2782 * This case is especially ugly. In order to reestablish the nexus, we
2783 * need to call NCR5380_select(). The easiest way to implement this
2784 * function was to abort if the bus was busy, and let the interrupt
2785 * handler triggered on the SEL for reselect take care of lost arbitrations
2786 * where necessary, meaning interrupts need to be enabled.
2787 *
2788 * When interrupts are enabled, the queues may change - so we
2789 * can't remove it from the disconnected queue before selecting it
2790 * because that could cause a failure in hashing the nexus if that
2791 * device reselected.
2792 *
2793 * Since the queues may change, we can't use the pointers from when we
2794 * first locate it.
2795 *
2796 * So, we must first locate the command, and if NCR5380_select()
2797 * succeeds, then issue the abort, relocate the command and remove
2798 * it from the disconnected queue.
2799 */
2800
2801 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp;
2802 tmp = NEXT(tmp))
2803 if (cmd == tmp) {
2804 restore_flags(flags);
2805 ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO);
2806
2807 if (NCR5380_select (instance, cmd, (int) cmd->tag))
2808 return SCSI_ABORT_BUSY;
2809
2810 ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO);
2811
2812 do_abort (instance);
2813
2814 save_flags(flags);
2815 cli();
2816 for (prev = (Scsi_Cmnd **) &(hostdata->disconnected_queue),
2817 tmp = (Scsi_Cmnd *) hostdata->disconnected_queue;
2818 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) )
2819 if (cmd == tmp) {
2820 REMOVE(5, *prev, tmp, NEXT(tmp));
2821 *prev = NEXT(tmp);
2822 NEXT(tmp) = NULL;
2823 tmp->result = DID_ABORT << 16;
2824 /* We must unlock the tag/LUN immediately here, since the
2825 * target goes to BUS FREE and doesn't send us another
2826 * message (COMMAND_COMPLETE or the like)
2827 */
2828 #ifdef SUPPORT_TAGS
2829 cmd_free_tag( tmp );
2830 #else
2831 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
2832 #endif
2833 restore_flags(flags);
2834 tmp->scsi_done(tmp);
2835 falcon_release_lock_if_possible( hostdata );
2836 return SCSI_ABORT_SUCCESS;
2837 }
2838 }
2839
2840 /*
2841 * Case 5 : If we reached this point, the command was not found in any of
2842 * the queues.
2843 *
2844 * We probably reached this point because of an unlikely race condition
2845 * between the command completing successfully and the abortion code,
2846 * so we won't panic, but we will notify the user in case something really
2847 * broke.
2848 */
2849
2850 restore_flags(flags);
2851 printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully\n"
2852 KERN_INFO " before abortion\n", HOSTNO);
2853
2854 /* Maybe it is sufficient just to release the ST-DMA lock... (if
2855 * possible at all) At least, we should check if the lock could be
2856 * released after the abort, in case it is kept due to some bug.
2857 */
2858 falcon_release_lock_if_possible( hostdata );
2859
2860 return SCSI_ABORT_NOT_RUNNING;
2861 }
2862
2863
2864 /*
2865 * Function : int NCR5380_reset (Scsi_Cmnd *cmd, unsigned int reset_flags)
2866 *
2867 * Purpose : reset the SCSI bus.
2868 *
2869 * Returns : SCSI_RESET_WAKEUP
2870 *
2871 */
2872
2873 static int NCR5380_reset( Scsi_Cmnd *cmd, unsigned int reset_flags)
2874 {
2875 SETUP_HOSTDATA(cmd->host);
2876 int i;
2877 unsigned long flags;
2878 #if 1
2879 Scsi_Cmnd *connected, *disconnected_queue;
2880 #endif
2881
2882 if (!IS_A_TT() && !falcon_got_lock)
2883 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n",
2884 H_NO(cmd) );
2885
2886 NCR5380_print_status (cmd->host);
2887
2888 /* get in phase */
2889 NCR5380_write( TARGET_COMMAND_REG,
2890 PHASE_SR_TO_TCR( NCR5380_read(STATUS_REG) ));
2891 /* assert RST */
2892 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST );
2893 udelay (40);
2894 /* reset NCR registers */
2895 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE );
2896 NCR5380_write( MODE_REG, MR_BASE );
2897 NCR5380_write( TARGET_COMMAND_REG, 0 );
2898 NCR5380_write( SELECT_ENABLE_REG, 0 );
2899 /* ++roman: reset interrupt condition! otherwise no interrupts don't get
2900 * through anymore ... */
2901 (void)NCR5380_read( RESET_PARITY_INTERRUPT_REG );
2902
2903 #if 1 /* XXX Should now be done by midlevel code, but it's broken XXX */
2904 /* XXX see below XXX */
2905
2906 /* MSch: old-style reset: actually abort all command processing here */
2907
2908 /* After the reset, there are no more connected or disconnected commands
2909 * and no busy units; to avoid problems with re-inserting the commands
2910 * into the issue_queue (via scsi_done()), the aborted commands are
2911 * remembered in local variables first.
2912 */
2913 save_flags(flags);
2914 cli();
2915 connected = (Scsi_Cmnd *)hostdata->connected;
2916 hostdata->connected = NULL;
2917 disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue;
2918 hostdata->disconnected_queue = NULL;
2919 #ifdef SUPPORT_TAGS
2920 free_all_tags();
2921 #endif
2922 for( i = 0; i < 8; ++i )
2923 hostdata->busy[i] = 0;
2924 #ifdef REAL_DMA
2925 hostdata->dma_len = 0;
2926 #endif
2927 restore_flags(flags);
2928
2929 /* In order to tell the mid-level code which commands were aborted,
2930 * set the command status to DID_RESET and call scsi_done() !!!
2931 * This ultimately aborts processing of these commands in the mid-level.
2932 */
2933
2934 if ((cmd = connected)) {
2935 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2936 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2937 cmd->scsi_done( cmd );
2938 }
2939
2940 for (i = 0; (cmd = disconnected_queue); ++i) {
2941 disconnected_queue = NEXT(cmd);
2942 NEXT(cmd) = NULL;
2943 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2944 cmd->scsi_done( cmd );
2945 }
2946 if (i > 0)
2947 ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i);
2948
2949 /* The Falcon lock should be released after a reset...
2950 */
2951 /* ++guenther: moved to atari_scsi_reset(), to prevent a race between
2952 * unlocking and enabling dma interrupt.
2953 */
2954 /* falcon_release_lock_if_possible( hostdata );*/
2955
2956 /* since all commands have been explicitly terminated, we need to tell
2957 * the midlevel code that the reset was SUCCESSFUL, and there is no
2958 * need to 'wake up' the commands by a request_sense
2959 */
2960 return SCSI_RESET_SUCCESS | SCSI_RESET_BUS_RESET;
2961 #else /* 1 */
2962
2963 /* MSch: new-style reset handling: let the mid-level do what it can */
2964
2965 /* ++guenther: MID-LEVEL IS STILL BROKEN.
2966 * Mid-level is supposed to requeue all commands that were active on the
2967 * various low-level queues. In fact it does this, but that's not enough
2968 * because all these commands are subject to timeout. And if a timeout
2969 * happens for any removed command, *_abort() is called but all queues
2970 * are now empty. Abort then gives up the falcon lock, which is fatal,
2971 * since the mid-level will queue more commands and must have the lock
2972 * (it's all happening inside timer interrupt handler!!).
2973 * Even worse, abort will return NOT_RUNNING for all those commands not
2974 * on any queue, so they won't be retried ...
2975 *
2976 * Conclusion: either scsi.c disables timeout for all resetted commands
2977 * immediately, or we loose! As of linux-2.0.20 it doesn't.
2978 */
2979
2980 /* After the reset, there are no more connected or disconnected commands
2981 * and no busy units; so clear the low-level status here to avoid
2982 * conflicts when the mid-level code tries to wake up the affected
2983 * commands!
2984 */
2985
2986 if (hostdata->issue_queue)
2987 ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2988 if (hostdata->connected)
2989 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2990 if (hostdata->disconnected_queue)
2991 ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
2992
2993 save_flags(flags);
2994 cli();
2995 hostdata->issue_queue = NULL;
2996 hostdata->connected = NULL;
2997 hostdata->disconnected_queue = NULL;
2998 #ifdef SUPPORT_TAGS
2999 free_all_tags();
3000 #endif
3001 for( i = 0; i < 8; ++i )
3002 hostdata->busy[i] = 0;
3003 #ifdef REAL_DMA
3004 hostdata->dma_len = 0;
3005 #endif
3006 restore_flags(flags);
3007
3008 /* we did no complete reset of all commands, so a wakeup is required */
3009 return SCSI_RESET_WAKEUP | SCSI_RESET_BUS_RESET;
3010 #endif /* 1 */
3011 }
3012
3013 /* Local Variables: */
3014 /* tab-width: 8 */
3015 /* End: */
3016