blob: 57295bcea3e766a4ae87d760ab6bf4cf1be35b32 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 */
db9dff32005-04-03 14:53:59 -050076#include <scsi/scsi_dbg.h>
Matthew Wilcox1abfd372005-12-15 16:22:01 -050077#include <scsi/scsi_transport_spi.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79#if (NDEBUG & NDEBUG_LISTS)
80#define LIST(x,y) \
81 { printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); \
82 if ((x)==(y)) udelay(5); }
83#define REMOVE(w,x,y,z) \
84 { printk("LINE:%d Removing: %p->%p %p->%p \n", __LINE__, \
85 (void*)(w), (void*)(x), (void*)(y), (void*)(z)); \
86 if ((x)==(y)) udelay(5); }
87#else
88#define LIST(x,y)
89#define REMOVE(w,x,y,z)
90#endif
91
92#ifndef notyet
93#undef LINKED
94#endif
95
96/*
97 * Design
98 * Issues :
99 *
100 * The other Linux SCSI drivers were written when Linux was Intel PC-only,
101 * and specifically for each board rather than each chip. This makes their
102 * adaptation to platforms like the Mac (Some of which use NCR5380's)
103 * more difficult than it has to be.
104 *
105 * Also, many of the SCSI drivers were written before the command queuing
106 * routines were implemented, meaning their implementations of queued
107 * commands were hacked on rather than designed in from the start.
108 *
109 * When I designed the Linux SCSI drivers I figured that
110 * while having two different SCSI boards in a system might be useful
111 * for debugging things, two of the same type wouldn't be used.
112 * Well, I was wrong and a number of users have mailed me about running
113 * multiple high-performance SCSI boards in a server.
114 *
115 * Finally, when I get questions from users, I have no idea what
116 * revision of my driver they are running.
117 *
118 * This driver attempts to address these problems :
119 * This is a generic 5380 driver. To use it on a different platform,
120 * one simply writes appropriate system specific macros (ie, data
121 * transfer - some PC's will use the I/O bus, 68K's must use
122 * memory mapped) and drops this file in their 'C' wrapper.
123 *
124 * As far as command queueing, two queues are maintained for
125 * each 5380 in the system - commands that haven't been issued yet,
126 * and commands that are currently executing. This means that an
127 * unlimited number of commands may be queued, letting
128 * more commands propagate from the higher driver levels giving higher
129 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
130 * allowing multiple commands to propagate all the way to a SCSI-II device
131 * while a command is already executing.
132 *
133 * To solve the multiple-boards-in-the-same-system problem,
134 * there is a separate instance structure for each instance
135 * of a 5380 in the system. So, multiple NCR5380 drivers will
136 * be able to coexist with appropriate changes to the high level
137 * SCSI code.
138 *
139 * A NCR5380_PUBLIC_REVISION macro is provided, with the release
140 * number (updated for each public release) printed by the
141 * NCR5380_print_options command, which should be called from the
142 * wrapper detect function, so that I know what release of the driver
143 * users are using.
144 *
145 * Issues specific to the NCR5380 :
146 *
147 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
148 * piece of hardware that requires you to sit in a loop polling for
149 * the REQ signal as long as you are connected. Some devices are
150 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
151 * while doing long seek operations.
152 *
153 * The workaround for this is to keep track of devices that have
154 * disconnected. If the device hasn't disconnected, for commands that
155 * should disconnect, we do something like
156 *
157 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
158 *
159 * Some tweaking of N and M needs to be done. An algorithm based
160 * on "time to data" would give the best results as long as short time
161 * to datas (ie, on the same track) were considered, however these
162 * broken devices are the exception rather than the rule and I'd rather
163 * spend my time optimizing for the normal case.
164 *
165 * Architecture :
166 *
167 * At the heart of the design is a coroutine, NCR5380_main,
168 * which is started when not running by the interrupt handler,
169 * timer, and queue command function. It attempts to establish
170 * I_T_L or I_T_L_Q nexuses by removing the commands from the
171 * issue queue and calling NCR5380_select() if a nexus
172 * is not established.
173 *
174 * Once a nexus is established, the NCR5380_information_transfer()
175 * phase goes through the various phases as instructed by the target.
176 * if the target goes into MSG IN and sends a DISCONNECT message,
177 * the command structure is placed into the per instance disconnected
178 * queue, and NCR5380_main tries to find more work. If USLEEP
179 * was defined, and the target is idle for too long, the system
180 * will try to sleep.
181 *
182 * If a command has disconnected, eventually an interrupt will trigger,
183 * calling NCR5380_intr() which will in turn call NCR5380_reselect
184 * to reestablish a nexus. This will run main if necessary.
185 *
186 * On command termination, the done function will be called as
187 * appropriate.
188 *
189 * SCSI pointers are maintained in the SCp field of SCSI command
190 * structures, being initialized after the command is connected
191 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
192 * Note that in violation of the standard, an implicit SAVE POINTERS operation
193 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
194 */
195
196/*
197 * Using this file :
198 * This file a skeleton Linux SCSI driver for the NCR 5380 series
199 * of chips. To use it, you write an architecture specific functions
200 * and macros and include this file in your driver.
201 *
202 * These macros control options :
203 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
204 * for commands that return with a CHECK CONDITION status.
205 *
206 * LINKED - if defined, linked commands are supported.
207 *
208 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
209 *
210 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
211 *
212 * These macros MUST be defined :
213 *
214 * NCR5380_read(register) - read from the specified register
215 *
216 * NCR5380_write(register, value) - write to the specific register
217 *
218 * Either real DMA *or* pseudo DMA may be implemented
219 * REAL functions :
220 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
221 * Note that the DMA setup functions should return the number of bytes
222 * that they were able to program the controller for.
223 *
224 * Also note that generic i386/PC versions of these macros are
225 * available as NCR5380_i386_dma_write_setup,
226 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
227 *
228 * NCR5380_dma_write_setup(instance, src, count) - initialize
229 * NCR5380_dma_read_setup(instance, dst, count) - initialize
230 * NCR5380_dma_residual(instance); - residual count
231 *
232 * PSEUDO functions :
233 * NCR5380_pwrite(instance, src, count)
234 * NCR5380_pread(instance, dst, count);
235 *
236 * If nothing specific to this implementation needs doing (ie, with external
237 * hardware), you must also define
238 *
239 * NCR5380_queue_command
240 * NCR5380_reset
241 * NCR5380_abort
242 * NCR5380_proc_info
243 *
244 * to be the global entry points into the specific driver, ie
245 * #define NCR5380_queue_command t128_queue_command.
246 *
247 * If this is not done, the routines will be defined as static functions
248 * with the NCR5380* names and the user must provide a globally
249 * accessible wrapper function.
250 *
251 * The generic driver is initialized by calling NCR5380_init(instance),
252 * after setting the appropriate host specific fields and ID. If the
253 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
254 * possible) function may be used. Before the specific driver initialization
255 * code finishes, NCR5380_print_options should be called.
256 */
257
258static struct Scsi_Host *first_instance = NULL;
Christoph Hellwigd0be4a7d2005-10-31 18:31:40 +0100259static struct scsi_host_template *the_template = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260
261/* Macros ease life... :-) */
262#define SETUP_HOSTDATA(in) \
263 struct NCR5380_hostdata *hostdata = \
264 (struct NCR5380_hostdata *)(in)->hostdata
265#define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)
266
267#define NEXT(cmd) ((Scsi_Cmnd *)((cmd)->host_scribble))
268#define NEXTADDR(cmd) ((Scsi_Cmnd **)&((cmd)->host_scribble))
269
270#define HOSTNO instance->host_no
271#define H_NO(cmd) (cmd)->device->host->host_no
272
273#ifdef SUPPORT_TAGS
274
275/*
276 * Functions for handling tagged queuing
277 * =====================================
278 *
279 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
280 *
281 * Using consecutive numbers for the tags is no good idea in my eyes. There
282 * could be wrong re-usings if the counter (8 bit!) wraps and some early
283 * command has been preempted for a long time. My solution: a bitfield for
284 * remembering used tags.
285 *
286 * There's also the problem that each target has a certain queue size, but we
287 * cannot know it in advance :-( We just see a QUEUE_FULL status being
288 * returned. So, in this case, the driver internal queue size assumption is
289 * reduced to the number of active tags if QUEUE_FULL is returned by the
290 * target. The command is returned to the mid-level, but with status changed
291 * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL
292 * correctly.
293 *
294 * We're also not allowed running tagged commands as long as an untagged
295 * command is active. And REQUEST SENSE commands after a contingent allegiance
296 * condition _must_ be untagged. To keep track whether an untagged command has
297 * been issued, the host->busy array is still employed, as it is without
298 * support for tagged queuing.
299 *
300 * One could suspect that there are possible race conditions between
301 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
302 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
303 * which already guaranteed to be running at most once. It is also the only
304 * place where tags/LUNs are allocated. So no other allocation can slip
305 * between that pair, there could only happen a reselection, which can free a
306 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
307 * important: the tag bit must be cleared before 'nr_allocated' is decreased.
308 */
309
310/* -1 for TAG_NONE is not possible with unsigned char cmd->tag */
311#undef TAG_NONE
312#define TAG_NONE 0xff
313
314typedef struct {
315 DECLARE_BITMAP(allocated, MAX_TAGS);
316 int nr_allocated;
317 int queue_size;
318} TAG_ALLOC;
319
320static TAG_ALLOC TagAlloc[8][8]; /* 8 targets and 8 LUNs */
321
322
323static void __init init_tags( void )
324{
325 int target, lun;
326 TAG_ALLOC *ta;
327
328 if (!setup_use_tagged_queuing)
329 return;
330
331 for( target = 0; target < 8; ++target ) {
332 for( lun = 0; lun < 8; ++lun ) {
333 ta = &TagAlloc[target][lun];
334 bitmap_zero(ta->allocated, MAX_TAGS);
335 ta->nr_allocated = 0;
336 /* At the beginning, assume the maximum queue size we could
337 * support (MAX_TAGS). This value will be decreased if the target
338 * returns QUEUE_FULL status.
339 */
340 ta->queue_size = MAX_TAGS;
341 }
342 }
343}
344
345
346/* Check if we can issue a command to this LUN: First see if the LUN is marked
347 * busy by an untagged command. If the command should use tagged queuing, also
348 * check that there is a free tag and the target's queue won't overflow. This
349 * function should be called with interrupts disabled to avoid race
350 * conditions.
351 */
352
353static int is_lun_busy( Scsi_Cmnd *cmd, int should_be_tagged )
354{
355 SETUP_HOSTDATA(cmd->device->host);
356
357 if (hostdata->busy[cmd->device->id] & (1 << cmd->device->lun))
358 return( 1 );
359 if (!should_be_tagged ||
360 !setup_use_tagged_queuing || !cmd->device->tagged_supported)
361 return( 0 );
362 if (TagAlloc[cmd->device->id][cmd->device->lun].nr_allocated >=
363 TagAlloc[cmd->device->id][cmd->device->lun].queue_size ) {
364 TAG_PRINTK( "scsi%d: target %d lun %d: no free tags\n",
365 H_NO(cmd), cmd->device->id, cmd->device->lun );
366 return( 1 );
367 }
368 return( 0 );
369}
370
371
372/* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
373 * must be called before!), or reserve the LUN in 'busy' if the command is
374 * untagged.
375 */
376
377static void cmd_get_tag( Scsi_Cmnd *cmd, int should_be_tagged )
378{
379 SETUP_HOSTDATA(cmd->device->host);
380
381 /* If we or the target don't support tagged queuing, allocate the LUN for
382 * an untagged command.
383 */
384 if (!should_be_tagged ||
385 !setup_use_tagged_queuing || !cmd->device->tagged_supported) {
386 cmd->tag = TAG_NONE;
387 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
388 TAG_PRINTK( "scsi%d: target %d lun %d now allocated by untagged "
389 "command\n", H_NO(cmd), cmd->device->id, cmd->device->lun );
390 }
391 else {
392 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
393
394 cmd->tag = find_first_zero_bit( ta->allocated, MAX_TAGS );
395 set_bit( cmd->tag, ta->allocated );
396 ta->nr_allocated++;
397 TAG_PRINTK( "scsi%d: using tag %d for target %d lun %d "
398 "(now %d tags in use)\n",
399 H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun,
400 ta->nr_allocated );
401 }
402}
403
404
405/* Mark the tag of command 'cmd' as free, or in case of an untagged command,
406 * unlock the LUN.
407 */
408
409static void cmd_free_tag( Scsi_Cmnd *cmd )
410{
411 SETUP_HOSTDATA(cmd->device->host);
412
413 if (cmd->tag == TAG_NONE) {
414 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
415 TAG_PRINTK( "scsi%d: target %d lun %d untagged cmd finished\n",
416 H_NO(cmd), cmd->device->id, cmd->device->lun );
417 }
418 else if (cmd->tag >= MAX_TAGS) {
419 printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n",
420 H_NO(cmd), cmd->tag );
421 }
422 else {
423 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
424 clear_bit( cmd->tag, ta->allocated );
425 ta->nr_allocated--;
426 TAG_PRINTK( "scsi%d: freed tag %d for target %d lun %d\n",
427 H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun );
428 }
429}
430
431
432static void free_all_tags( void )
433{
434 int target, lun;
435 TAG_ALLOC *ta;
436
437 if (!setup_use_tagged_queuing)
438 return;
439
440 for( target = 0; target < 8; ++target ) {
441 for( lun = 0; lun < 8; ++lun ) {
442 ta = &TagAlloc[target][lun];
443 bitmap_zero(ta->allocated, MAX_TAGS);
444 ta->nr_allocated = 0;
445 }
446 }
447}
448
449#endif /* SUPPORT_TAGS */
450
451
452/*
453 * Function: void merge_contiguous_buffers( Scsi_Cmnd *cmd )
454 *
455 * Purpose: Try to merge several scatter-gather requests into one DMA
456 * transfer. This is possible if the scatter buffers lie on
457 * physical contiguous addresses.
458 *
459 * Parameters: Scsi_Cmnd *cmd
460 * The command to work on. The first scatter buffer's data are
461 * assumed to be already transfered into ptr/this_residual.
462 */
463
464static void merge_contiguous_buffers( Scsi_Cmnd *cmd )
465{
466 unsigned long endaddr;
467#if (NDEBUG & NDEBUG_MERGING)
468 unsigned long oldlen = cmd->SCp.this_residual;
469 int cnt = 1;
470#endif
471
472 for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
473 cmd->SCp.buffers_residual &&
474 virt_to_phys(page_address(cmd->SCp.buffer[1].page)+
475 cmd->SCp.buffer[1].offset) == endaddr; ) {
476 MER_PRINTK("VTOP(%p) == %08lx -> merging\n",
477 cmd->SCp.buffer[1].address, endaddr);
478#if (NDEBUG & NDEBUG_MERGING)
479 ++cnt;
480#endif
481 ++cmd->SCp.buffer;
482 --cmd->SCp.buffers_residual;
483 cmd->SCp.this_residual += cmd->SCp.buffer->length;
484 endaddr += cmd->SCp.buffer->length;
485 }
486#if (NDEBUG & NDEBUG_MERGING)
487 if (oldlen != cmd->SCp.this_residual)
488 MER_PRINTK("merged %d buffers from %p, new length %08x\n",
489 cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
490#endif
491}
492
493/*
494 * Function : void initialize_SCp(Scsi_Cmnd *cmd)
495 *
496 * Purpose : initialize the saved data pointers for cmd to point to the
497 * start of the buffer.
498 *
499 * Inputs : cmd - Scsi_Cmnd structure to have pointers reset.
500 */
501
502static __inline__ void initialize_SCp(Scsi_Cmnd *cmd)
503{
504 /*
505 * Initialize the Scsi Pointer field so that all of the commands in the
506 * various queues are valid.
507 */
508
509 if (cmd->use_sg) {
510 cmd->SCp.buffer = (struct scatterlist *) cmd->buffer;
511 cmd->SCp.buffers_residual = cmd->use_sg - 1;
512 cmd->SCp.ptr = (char *)page_address(cmd->SCp.buffer->page)+
513 cmd->SCp.buffer->offset;
514 cmd->SCp.this_residual = cmd->SCp.buffer->length;
515 /* ++roman: Try to merge some scatter-buffers if they are at
516 * contiguous physical addresses.
517 */
518 merge_contiguous_buffers( cmd );
519 } else {
520 cmd->SCp.buffer = NULL;
521 cmd->SCp.buffers_residual = 0;
522 cmd->SCp.ptr = (char *) cmd->request_buffer;
523 cmd->SCp.this_residual = cmd->request_bufflen;
524 }
525}
526
527#include <linux/config.h>
528#include <linux/delay.h>
529
530#if NDEBUG
531static struct {
532 unsigned char mask;
533 const char * name;}
534signals[] = {{ SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" },
535 { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" },
536 { SR_SEL, "SEL" }, {0, NULL}},
537basrs[] = {{BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}},
538icrs[] = {{ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"},
539 {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"},
540 {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"},
541 {0, NULL}},
542mrs[] = {{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"},
543 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR,
544 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"},
545 {MR_MONITOR_BSY, "MODE MONITOR BSY"},
546 {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"},
547 {0, NULL}};
548
549/*
550 * Function : void NCR5380_print(struct Scsi_Host *instance)
551 *
552 * Purpose : print the SCSI bus signals for debugging purposes
553 *
554 * Input : instance - which NCR5380
555 */
556
557static void NCR5380_print(struct Scsi_Host *instance) {
558 unsigned char status, data, basr, mr, icr, i;
559 unsigned long flags;
560
561 local_irq_save(flags);
562 data = NCR5380_read(CURRENT_SCSI_DATA_REG);
563 status = NCR5380_read(STATUS_REG);
564 mr = NCR5380_read(MODE_REG);
565 icr = NCR5380_read(INITIATOR_COMMAND_REG);
566 basr = NCR5380_read(BUS_AND_STATUS_REG);
567 local_irq_restore(flags);
568 printk("STATUS_REG: %02x ", status);
569 for (i = 0; signals[i].mask ; ++i)
570 if (status & signals[i].mask)
571 printk(",%s", signals[i].name);
572 printk("\nBASR: %02x ", basr);
573 for (i = 0; basrs[i].mask ; ++i)
574 if (basr & basrs[i].mask)
575 printk(",%s", basrs[i].name);
576 printk("\nICR: %02x ", icr);
577 for (i = 0; icrs[i].mask; ++i)
578 if (icr & icrs[i].mask)
579 printk(",%s", icrs[i].name);
580 printk("\nMODE: %02x ", mr);
581 for (i = 0; mrs[i].mask; ++i)
582 if (mr & mrs[i].mask)
583 printk(",%s", mrs[i].name);
584 printk("\n");
585}
586
587static struct {
588 unsigned char value;
589 const char *name;
590} phases[] = {
591 {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
592 {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
593 {PHASE_UNKNOWN, "UNKNOWN"}};
594
595/*
596 * Function : void NCR5380_print_phase(struct Scsi_Host *instance)
597 *
598 * Purpose : print the current SCSI phase for debugging purposes
599 *
600 * Input : instance - which NCR5380
601 */
602
603static void NCR5380_print_phase(struct Scsi_Host *instance)
604{
605 unsigned char status;
606 int i;
607
608 status = NCR5380_read(STATUS_REG);
609 if (!(status & SR_REQ))
610 printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO);
611 else {
612 for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
613 (phases[i].value != (status & PHASE_MASK)); ++i);
614 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name);
615 }
616}
617
618#else /* !NDEBUG */
619
620/* dummies... */
621__inline__ void NCR5380_print(struct Scsi_Host *instance) { };
622__inline__ void NCR5380_print_phase(struct Scsi_Host *instance) { };
623
624#endif
625
626/*
627 * ++roman: New scheme of calling NCR5380_main()
628 *
629 * If we're not in an interrupt, we can call our main directly, it cannot be
630 * already running. Else, we queue it on a task queue, if not 'main_running'
631 * tells us that a lower level is already executing it. This way,
632 * 'main_running' needs not be protected in a special way.
633 *
634 * queue_main() is a utility function for putting our main onto the task
635 * queue, if main_running is false. It should be called only from a
636 * interrupt or bottom half.
637 */
638
639#include <linux/workqueue.h>
640#include <linux/interrupt.h>
641
642static volatile int main_running = 0;
643static DECLARE_WORK(NCR5380_tqueue, (void (*)(void*))NCR5380_main, NULL);
644
645static __inline__ void queue_main(void)
646{
647 if (!main_running) {
648 /* If in interrupt and NCR5380_main() not already running,
649 queue it on the 'immediate' task queue, to be processed
650 immediately after the current interrupt processing has
651 finished. */
652 schedule_work(&NCR5380_tqueue);
653 }
654 /* else: nothing to do: the running NCR5380_main() will pick up
655 any newly queued command. */
656}
657
658
659static inline void NCR5380_all_init (void)
660{
661 static int done = 0;
662 if (!done) {
663 INI_PRINTK("scsi : NCR5380_all_init()\n");
664 done = 1;
665 }
666}
667
668
669/*
670 * Function : void NCR58380_print_options (struct Scsi_Host *instance)
671 *
672 * Purpose : called by probe code indicating the NCR5380 driver
673 * options that were selected.
674 *
675 * Inputs : instance, pointer to this instance. Unused.
676 */
677
678static void __init NCR5380_print_options (struct Scsi_Host *instance)
679{
680 printk(" generic options"
681#ifdef AUTOSENSE
682 " AUTOSENSE"
683#endif
684#ifdef REAL_DMA
685 " REAL DMA"
686#endif
687#ifdef PARITY
688 " PARITY"
689#endif
690#ifdef SUPPORT_TAGS
691 " SCSI-2 TAGGED QUEUING"
692#endif
693 );
694 printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
695}
696
697/*
698 * Function : void NCR5380_print_status (struct Scsi_Host *instance)
699 *
700 * Purpose : print commands in the various queues, called from
701 * NCR5380_abort and NCR5380_debug to aid debugging.
702 *
703 * Inputs : instance, pointer to this instance.
704 */
705
706static void NCR5380_print_status (struct Scsi_Host *instance)
707{
708 char *pr_bfr;
709 char *start;
710 int len;
711
712 NCR_PRINT(NDEBUG_ANY);
713 NCR_PRINT_PHASE(NDEBUG_ANY);
714
715 pr_bfr = (char *) __get_free_page(GFP_ATOMIC);
716 if (!pr_bfr) {
717 printk("NCR5380_print_status: no memory for print buffer\n");
718 return;
719 }
720 len = NCR5380_proc_info(pr_bfr, &start, 0, PAGE_SIZE, HOSTNO, 0);
721 pr_bfr[len] = 0;
722 printk("\n%s\n", pr_bfr);
723 free_page((unsigned long) pr_bfr);
724}
725
726
727/******************************************/
728/*
729 * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
730 *
731 * *buffer: I/O buffer
732 * **start: if inout == FALSE pointer into buffer where user read should start
733 * offset: current offset
734 * length: length of buffer
735 * hostno: Scsi_Host host_no
736 * inout: TRUE - user is writing; FALSE - user is reading
737 *
738 * Return the number of bytes read from or written
739*/
740
741#undef SPRINTF
742#define SPRINTF(fmt,args...) \
743 do { if (pos + strlen(fmt) + 20 /* slop */ < buffer + length) \
744 pos += sprintf(pos, fmt , ## args); } while(0)
745static
746char *lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length);
747
748static
749int NCR5380_proc_info (struct Scsi_Host *instance, char *buffer, char **start, off_t offset,
750 int length, int inout)
751{
752 char *pos = buffer;
753 struct NCR5380_hostdata *hostdata;
754 Scsi_Cmnd *ptr;
755 unsigned long flags;
756 off_t begin = 0;
757#define check_offset() \
758 do { \
759 if (pos - buffer < offset - begin) { \
760 begin += pos - buffer; \
761 pos = buffer; \
762 } \
763 } while (0)
764
765 hostdata = (struct NCR5380_hostdata *)instance->hostdata;
766
767 if (inout) { /* Has data been written to the file ? */
768 return(-ENOSYS); /* Currently this is a no-op */
769 }
770 SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
771 check_offset();
772 local_irq_save(flags);
773 SPRINTF("NCR5380: coroutine is%s running.\n", main_running ? "" : "n't");
774 check_offset();
775 if (!hostdata->connected)
776 SPRINTF("scsi%d: no currently connected command\n", HOSTNO);
777 else
778 pos = lprint_Scsi_Cmnd ((Scsi_Cmnd *) hostdata->connected,
779 pos, buffer, length);
780 SPRINTF("scsi%d: issue_queue\n", HOSTNO);
781 check_offset();
782 for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = NEXT(ptr)) {
783 pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
784 check_offset();
785 }
786
787 SPRINTF("scsi%d: disconnected_queue\n", HOSTNO);
788 check_offset();
789 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr;
790 ptr = NEXT(ptr)) {
791 pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
792 check_offset();
793 }
794
795 local_irq_restore(flags);
796 *start = buffer + (offset - begin);
797 if (pos - buffer < offset - begin)
798 return 0;
799 else if (pos - buffer - (offset - begin) < length)
800 return pos - buffer - (offset - begin);
801 return length;
802}
803
804static char *
805lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length)
806{
807 int i, s;
808 unsigned char *command;
809 SPRINTF("scsi%d: destination target %d, lun %d\n",
810 H_NO(cmd), cmd->device->id, cmd->device->lun);
811 SPRINTF(" command = ");
812 command = cmd->cmnd;
813 SPRINTF("%2d (0x%02x)", command[0], command[0]);
814 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
815 SPRINTF(" %02x", command[i]);
816 SPRINTF("\n");
817 return pos;
818}
819
820
821/*
822 * Function : void NCR5380_init (struct Scsi_Host *instance)
823 *
824 * Purpose : initializes *instance and corresponding 5380 chip.
825 *
826 * Inputs : instance - instantiation of the 5380 driver.
827 *
828 * Notes : I assume that the host, hostno, and id bits have been
829 * set correctly. I don't care about the irq and other fields.
830 *
831 */
832
833static int NCR5380_init (struct Scsi_Host *instance, int flags)
834{
835 int i;
836 SETUP_HOSTDATA(instance);
837
838 NCR5380_all_init();
839
840 hostdata->aborted = 0;
841 hostdata->id_mask = 1 << instance->this_id;
842 hostdata->id_higher_mask = 0;
843 for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
844 if (i > hostdata->id_mask)
845 hostdata->id_higher_mask |= i;
846 for (i = 0; i < 8; ++i)
847 hostdata->busy[i] = 0;
848#ifdef SUPPORT_TAGS
849 init_tags();
850#endif
851#if defined (REAL_DMA)
852 hostdata->dma_len = 0;
853#endif
854 hostdata->targets_present = 0;
855 hostdata->connected = NULL;
856 hostdata->issue_queue = NULL;
857 hostdata->disconnected_queue = NULL;
858 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT;
859
860 if (!the_template) {
861 the_template = instance->hostt;
862 first_instance = instance;
863 }
864
865
866#ifndef AUTOSENSE
867 if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1))
868 printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n"
869 " without AUTOSENSE option, contingent allegiance conditions may\n"
870 " be incorrectly cleared.\n", HOSTNO);
871#endif /* def AUTOSENSE */
872
873 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
874 NCR5380_write(MODE_REG, MR_BASE);
875 NCR5380_write(TARGET_COMMAND_REG, 0);
876 NCR5380_write(SELECT_ENABLE_REG, 0);
877
878 return 0;
879}
880
881/*
882 * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd,
883 * void (*done)(Scsi_Cmnd *))
884 *
885 * Purpose : enqueues a SCSI command
886 *
887 * Inputs : cmd - SCSI command, done - function called on completion, with
888 * a pointer to the command descriptor.
889 *
890 * Returns : 0
891 *
892 * Side effects :
893 * cmd is added to the per instance issue_queue, with minor
894 * twiddling done to the host specific fields of cmd. If the
895 * main coroutine is not running, it is restarted.
896 *
897 */
898
899static
900int NCR5380_queue_command (Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
901{
902 SETUP_HOSTDATA(cmd->device->host);
903 Scsi_Cmnd *tmp;
904 int oldto;
905 unsigned long flags;
906 extern int update_timeout(Scsi_Cmnd * SCset, int timeout);
907
908#if (NDEBUG & NDEBUG_NO_WRITE)
909 switch (cmd->cmnd[0]) {
910 case WRITE_6:
911 case WRITE_10:
912 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
913 H_NO(cmd));
914 cmd->result = (DID_ERROR << 16);
915 done(cmd);
916 return 0;
917 }
918#endif /* (NDEBUG & NDEBUG_NO_WRITE) */
919
920
921#ifdef NCR5380_STATS
922# if 0
923 if (!hostdata->connected && !hostdata->issue_queue &&
924 !hostdata->disconnected_queue) {
925 hostdata->timebase = jiffies;
926 }
927# endif
928# ifdef NCR5380_STAT_LIMIT
929 if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
930# endif
931 switch (cmd->cmnd[0])
932 {
933 case WRITE:
934 case WRITE_6:
935 case WRITE_10:
936 hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
937 hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen;
938 hostdata->pendingw++;
939 break;
940 case READ:
941 case READ_6:
942 case READ_10:
943 hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
944 hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen;
945 hostdata->pendingr++;
946 break;
947 }
948#endif
949
950 /*
951 * We use the host_scribble field as a pointer to the next command
952 * in a queue
953 */
954
955 NEXT(cmd) = NULL;
956 cmd->scsi_done = done;
957
958 cmd->result = 0;
959
960
961 /*
962 * Insert the cmd into the issue queue. Note that REQUEST SENSE
963 * commands are added to the head of the queue since any command will
964 * clear the contingent allegiance condition that exists and the
965 * sense data is only guaranteed to be valid while the condition exists.
966 */
967
968 local_irq_save(flags);
969 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
970 * Otherwise a running NCR5380_main may steal the lock.
971 * Lock before actually inserting due to fairness reasons explained in
972 * atari_scsi.c. If we insert first, then it's impossible for this driver
973 * to release the lock.
974 * Stop timer for this command while waiting for the lock, or timeouts
975 * may happen (and they really do), and it's no good if the command doesn't
976 * appear in any of the queues.
977 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
978 * because also a timer int can trigger an abort or reset, which would
979 * alter queues and touch the lock.
980 */
981 if (!IS_A_TT()) {
982 oldto = update_timeout(cmd, 0);
983 falcon_get_lock();
984 update_timeout(cmd, oldto);
985 }
986 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
987 LIST(cmd, hostdata->issue_queue);
988 NEXT(cmd) = hostdata->issue_queue;
989 hostdata->issue_queue = cmd;
990 } else {
991 for (tmp = (Scsi_Cmnd *)hostdata->issue_queue;
992 NEXT(tmp); tmp = NEXT(tmp))
993 ;
994 LIST(cmd, tmp);
995 NEXT(tmp) = cmd;
996 }
997 local_irq_restore(flags);
998
999 QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd),
1000 (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
1001
1002 /* If queue_command() is called from an interrupt (real one or bottom
1003 * half), we let queue_main() do the job of taking care about main. If it
1004 * is already running, this is a no-op, else main will be queued.
1005 *
1006 * If we're not in an interrupt, we can call NCR5380_main()
1007 * unconditionally, because it cannot be already running.
1008 */
1009 if (in_interrupt() || ((flags >> 8) & 7) >= 6)
1010 queue_main();
1011 else
1012 NCR5380_main(NULL);
1013 return 0;
1014}
1015
1016/*
1017 * Function : NCR5380_main (void)
1018 *
1019 * Purpose : NCR5380_main is a coroutine that runs as long as more work can
1020 * be done on the NCR5380 host adapters in a system. Both
1021 * NCR5380_queue_command() and NCR5380_intr() will try to start it
1022 * in case it is not running.
1023 *
1024 * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
1025 * reenable them. This prevents reentrancy and kernel stack overflow.
1026 */
1027
1028static void NCR5380_main (void *bl)
1029{
1030 Scsi_Cmnd *tmp, *prev;
1031 struct Scsi_Host *instance = first_instance;
1032 struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
1033 int done;
1034 unsigned long flags;
1035
1036 /*
1037 * We run (with interrupts disabled) until we're sure that none of
1038 * the host adapters have anything that can be done, at which point
1039 * we set main_running to 0 and exit.
1040 *
1041 * Interrupts are enabled before doing various other internal
1042 * instructions, after we've decided that we need to run through
1043 * the loop again.
1044 *
1045 * this should prevent any race conditions.
1046 *
1047 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1048 * because also a timer int can trigger an abort or reset, which can
1049 * alter queues and touch the Falcon lock.
1050 */
1051
1052 /* Tell int handlers main() is now already executing. Note that
1053 no races are possible here. If an int comes in before
1054 'main_running' is set here, and queues/executes main via the
1055 task queue, it doesn't do any harm, just this instance of main
1056 won't find any work left to do. */
1057 if (main_running)
1058 return;
1059 main_running = 1;
1060
1061 local_save_flags(flags);
1062 do {
1063 local_irq_disable(); /* Freeze request queues */
1064 done = 1;
1065
1066 if (!hostdata->connected) {
1067 MAIN_PRINTK( "scsi%d: not connected\n", HOSTNO );
1068 /*
1069 * Search through the issue_queue for a command destined
1070 * for a target that's not busy.
1071 */
1072#if (NDEBUG & NDEBUG_LISTS)
1073 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL;
1074 tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
1075 ;
1076 /*printk("%p ", tmp);*/
1077 if ((tmp == prev) && tmp) printk(" LOOP\n");/* else printk("\n");*/
1078#endif
1079 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue,
1080 prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp) ) {
1081
1082#if (NDEBUG & NDEBUG_LISTS)
1083 if (prev != tmp)
1084 printk("MAIN tmp=%p target=%d busy=%d lun=%d\n",
1085 tmp, tmp->device->id, hostdata->busy[tmp->device->id],
1086 tmp->device->lun);
1087#endif
1088 /* When we find one, remove it from the issue queue. */
1089 /* ++guenther: possible race with Falcon locking */
1090 if (
1091#ifdef SUPPORT_TAGS
1092 !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
1093#else
1094 !(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))
1095#endif
1096 ) {
1097 /* ++guenther: just to be sure, this must be atomic */
1098 local_irq_disable();
1099 if (prev) {
1100 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1101 NEXT(prev) = NEXT(tmp);
1102 } else {
1103 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
1104 hostdata->issue_queue = NEXT(tmp);
1105 }
1106 NEXT(tmp) = NULL;
1107 falcon_dont_release++;
1108
1109 /* reenable interrupts after finding one */
1110 local_irq_restore(flags);
1111
1112 /*
1113 * Attempt to establish an I_T_L nexus here.
1114 * On success, instance->hostdata->connected is set.
1115 * On failure, we must add the command back to the
1116 * issue queue so we can keep trying.
1117 */
1118 MAIN_PRINTK("scsi%d: main(): command for target %d "
1119 "lun %d removed from issue_queue\n",
1120 HOSTNO, tmp->device->id, tmp->device->lun);
1121 /*
1122 * REQUEST SENSE commands are issued without tagged
1123 * queueing, even on SCSI-II devices because the
1124 * contingent allegiance condition exists for the
1125 * entire unit.
1126 */
1127 /* ++roman: ...and the standard also requires that
1128 * REQUEST SENSE command are untagged.
1129 */
1130
1131#ifdef SUPPORT_TAGS
1132 cmd_get_tag( tmp, tmp->cmnd[0] != REQUEST_SENSE );
1133#endif
1134 if (!NCR5380_select(instance, tmp,
1135 (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE :
1136 TAG_NEXT)) {
1137 falcon_dont_release--;
1138 /* release if target did not response! */
1139 falcon_release_lock_if_possible( hostdata );
1140 break;
1141 } else {
1142 local_irq_disable();
1143 LIST(tmp, hostdata->issue_queue);
1144 NEXT(tmp) = hostdata->issue_queue;
1145 hostdata->issue_queue = tmp;
1146#ifdef SUPPORT_TAGS
1147 cmd_free_tag( tmp );
1148#endif
1149 falcon_dont_release--;
1150 local_irq_restore(flags);
1151 MAIN_PRINTK("scsi%d: main(): select() failed, "
1152 "returned to issue_queue\n", HOSTNO);
1153 if (hostdata->connected)
1154 break;
1155 }
1156 } /* if target/lun/target queue is not busy */
1157 } /* for issue_queue */
1158 } /* if (!hostdata->connected) */
1159
1160 if (hostdata->connected
1161#ifdef REAL_DMA
1162 && !hostdata->dma_len
1163#endif
1164 ) {
1165 local_irq_restore(flags);
1166 MAIN_PRINTK("scsi%d: main: performing information transfer\n",
1167 HOSTNO);
1168 NCR5380_information_transfer(instance);
1169 MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO);
1170 done = 0;
1171 }
1172 } while (!done);
1173
1174 /* Better allow ints _after_ 'main_running' has been cleared, else
1175 an interrupt could believe we'll pick up the work it left for
1176 us, but we won't see it anymore here... */
1177 main_running = 0;
1178 local_irq_restore(flags);
1179}
1180
1181
1182#ifdef REAL_DMA
1183/*
1184 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1185 *
1186 * Purpose : Called by interrupt handler when DMA finishes or a phase
1187 * mismatch occurs (which would finish the DMA transfer).
1188 *
1189 * Inputs : instance - this instance of the NCR5380.
1190 *
1191 */
1192
1193static void NCR5380_dma_complete( struct Scsi_Host *instance )
1194{
1195 SETUP_HOSTDATA(instance);
1196 int transfered, saved_data = 0, overrun = 0, cnt, toPIO;
1197 unsigned char **data, p;
1198 volatile int *count;
1199
1200 if (!hostdata->connected) {
1201 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
1202 "no connected cmd\n", HOSTNO);
1203 return;
1204 }
1205
1206 if (atari_read_overruns) {
1207 p = hostdata->connected->SCp.phase;
1208 if (p & SR_IO) {
1209 udelay(10);
1210 if ((((NCR5380_read(BUS_AND_STATUS_REG)) &
1211 (BASR_PHASE_MATCH|BASR_ACK)) ==
1212 (BASR_PHASE_MATCH|BASR_ACK))) {
1213 saved_data = NCR5380_read(INPUT_DATA_REG);
1214 overrun = 1;
1215 DMA_PRINTK("scsi%d: read overrun handled\n", HOSTNO);
1216 }
1217 }
1218 }
1219
1220 DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1221 HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
1222 NCR5380_read(STATUS_REG));
1223
1224 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1225 NCR5380_write(MODE_REG, MR_BASE);
1226 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1227
1228 transfered = hostdata->dma_len - NCR5380_dma_residual(instance);
1229 hostdata->dma_len = 0;
1230
1231 data = (unsigned char **) &(hostdata->connected->SCp.ptr);
1232 count = &(hostdata->connected->SCp.this_residual);
1233 *data += transfered;
1234 *count -= transfered;
1235
1236 if (atari_read_overruns) {
1237 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
1238 cnt = toPIO = atari_read_overruns;
1239 if (overrun) {
1240 DMA_PRINTK("Got an input overrun, using saved byte\n");
1241 *(*data)++ = saved_data;
1242 (*count)--;
1243 cnt--;
1244 toPIO--;
1245 }
1246 DMA_PRINTK("Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
1247 NCR5380_transfer_pio(instance, &p, &cnt, data);
1248 *count -= toPIO - cnt;
1249 }
1250 }
1251}
1252#endif /* REAL_DMA */
1253
1254
1255/*
1256 * Function : void NCR5380_intr (int irq)
1257 *
1258 * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1259 * from the disconnected queue, and restarting NCR5380_main()
1260 * as required.
1261 *
1262 * Inputs : int irq, irq that caused this interrupt.
1263 *
1264 */
1265
1266static irqreturn_t NCR5380_intr (int irq, void *dev_id, struct pt_regs *regs)
1267{
1268 struct Scsi_Host *instance = first_instance;
1269 int done = 1, handled = 0;
1270 unsigned char basr;
1271
1272 INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO);
1273
1274 /* Look for pending interrupts */
1275 basr = NCR5380_read(BUS_AND_STATUS_REG);
1276 INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr);
1277 /* dispatch to appropriate routine if found and done=0 */
1278 if (basr & BASR_IRQ) {
1279 NCR_PRINT(NDEBUG_INTR);
1280 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
1281 done = 0;
1282 ENABLE_IRQ();
1283 INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO);
1284 NCR5380_reselect(instance);
1285 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1286 }
1287 else if (basr & BASR_PARITY_ERROR) {
1288 INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO);
1289 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1290 }
1291 else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1292 INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO);
1293 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1294 }
1295 else {
1296 /*
1297 * The rest of the interrupt conditions can occur only during a
1298 * DMA transfer
1299 */
1300
1301#if defined(REAL_DMA)
1302 /*
1303 * We should only get PHASE MISMATCH and EOP interrupts if we have
1304 * DMA enabled, so do a sanity check based on the current setting
1305 * of the MODE register.
1306 */
1307
1308 if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
1309 ((basr & BASR_END_DMA_TRANSFER) ||
1310 !(basr & BASR_PHASE_MATCH))) {
1311
1312 INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1313 NCR5380_dma_complete( instance );
1314 done = 0;
1315 ENABLE_IRQ();
1316 } else
1317#endif /* REAL_DMA */
1318 {
1319/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1320 if (basr & BASR_PHASE_MATCH)
1321 printk(KERN_NOTICE "scsi%d: unknown interrupt, "
1322 "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1323 HOSTNO, basr, NCR5380_read(MODE_REG),
1324 NCR5380_read(STATUS_REG));
1325 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1326 }
1327 } /* if !(SELECTION || PARITY) */
1328 handled = 1;
1329 } /* BASR & IRQ */
1330 else {
1331 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
1332 "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
1333 NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG));
1334 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1335 }
1336
1337 if (!done) {
1338 INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO);
1339 /* Put a call to NCR5380_main() on the queue... */
1340 queue_main();
1341 }
1342 return IRQ_RETVAL(handled);
1343}
1344
1345#ifdef NCR5380_STATS
1346static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd* cmd)
1347{
1348# ifdef NCR5380_STAT_LIMIT
1349 if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
1350# endif
1351 switch (cmd->cmnd[0])
1352 {
1353 case WRITE:
1354 case WRITE_6:
1355 case WRITE_10:
1356 hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase);
1357 /*hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen;*/
1358 hostdata->pendingw--;
1359 break;
1360 case READ:
1361 case READ_6:
1362 case READ_10:
1363 hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase);
1364 /*hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen;*/
1365 hostdata->pendingr--;
1366 break;
1367 }
1368}
1369#endif
1370
1371/*
1372 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1373 * int tag);
1374 *
1375 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1376 * including ARBITRATION, SELECTION, and initial message out for
1377 * IDENTIFY and queue messages.
1378 *
1379 * Inputs : instance - instantiation of the 5380 driver on which this
1380 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1381 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1382 * the command that is presently connected.
1383 *
1384 * Returns : -1 if selection could not execute for some reason,
1385 * 0 if selection succeeded or failed because the target
1386 * did not respond.
1387 *
1388 * Side effects :
1389 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1390 * with registers as they should have been on entry - ie
1391 * SELECT_ENABLE will be set appropriately, the NCR5380
1392 * will cease to drive any SCSI bus signals.
1393 *
1394 * If successful : I_T_L or I_T_L_Q nexus will be established,
1395 * instance->connected will be set to cmd.
1396 * SELECT interrupt will be disabled.
1397 *
1398 * If failed (no target) : cmd->scsi_done() will be called, and the
1399 * cmd->result host byte set to DID_BAD_TARGET.
1400 */
1401
1402static int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag)
1403{
1404 SETUP_HOSTDATA(instance);
1405 unsigned char tmp[3], phase;
1406 unsigned char *data;
1407 int len;
1408 unsigned long timeout;
1409 unsigned long flags;
1410
1411 hostdata->restart_select = 0;
1412 NCR_PRINT(NDEBUG_ARBITRATION);
1413 ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO,
1414 instance->this_id);
1415
1416 /*
1417 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1418 * data bus during SELECTION.
1419 */
1420
1421 local_irq_save(flags);
1422 if (hostdata->connected) {
1423 local_irq_restore(flags);
1424 return -1;
1425 }
1426 NCR5380_write(TARGET_COMMAND_REG, 0);
1427
1428
1429 /*
1430 * Start arbitration.
1431 */
1432
1433 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1434 NCR5380_write(MODE_REG, MR_ARBITRATE);
1435
1436 local_irq_restore(flags);
1437
1438 /* Wait for arbitration logic to complete */
1439#if NCR_TIMEOUT
1440 {
1441 unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
1442
1443 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)
1444 && time_before(jiffies, timeout) && !hostdata->connected)
1445 ;
1446 if (time_after_eq(jiffies, timeout))
1447 {
1448 printk("scsi : arbitration timeout at %d\n", __LINE__);
1449 NCR5380_write(MODE_REG, MR_BASE);
1450 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1451 return -1;
1452 }
1453 }
1454#else /* NCR_TIMEOUT */
1455 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)
1456 && !hostdata->connected);
1457#endif
1458
1459 ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO);
1460
1461 if (hostdata->connected) {
1462 NCR5380_write(MODE_REG, MR_BASE);
1463 return -1;
1464 }
1465 /*
1466 * The arbitration delay is 2.2us, but this is a minimum and there is
1467 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1468 * the integral nature of udelay().
1469 *
1470 */
1471
1472 udelay(3);
1473
1474 /* Check for lost arbitration */
1475 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1476 (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
1477 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1478 hostdata->connected) {
1479 NCR5380_write(MODE_REG, MR_BASE);
1480 ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1481 HOSTNO);
1482 return -1;
1483 }
1484
1485 /* after/during arbitration, BSY should be asserted.
1486 IBM DPES-31080 Version S31Q works now */
1487 /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
1488 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL |
1489 ICR_ASSERT_BSY ) ;
1490
1491 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1492 hostdata->connected) {
1493 NCR5380_write(MODE_REG, MR_BASE);
1494 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1495 ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1496 HOSTNO);
1497 return -1;
1498 }
1499
1500 /*
1501 * Again, bus clear + bus settle time is 1.2us, however, this is
1502 * a minimum so we'll udelay ceil(1.2)
1503 */
1504
1505#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1506 /* ++roman: But some targets (see above :-) seem to need a bit more... */
1507 udelay(15);
1508#else
1509 udelay(2);
1510#endif
1511
1512 if (hostdata->connected) {
1513 NCR5380_write(MODE_REG, MR_BASE);
1514 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1515 return -1;
1516 }
1517
1518 ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO);
1519
1520 /*
1521 * Now that we have won arbitration, start Selection process, asserting
1522 * the host and target ID's on the SCSI bus.
1523 */
1524
1525 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id)));
1526
1527 /*
1528 * Raise ATN while SEL is true before BSY goes false from arbitration,
1529 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1530 * phase immediately after selection.
1531 */
1532
1533 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY |
1534 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL ));
1535 NCR5380_write(MODE_REG, MR_BASE);
1536
1537 /*
1538 * Reselect interrupts must be turned off prior to the dropping of BSY,
1539 * otherwise we will trigger an interrupt.
1540 */
1541
1542 if (hostdata->connected) {
1543 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1544 return -1;
1545 }
1546
1547 NCR5380_write(SELECT_ENABLE_REG, 0);
1548
1549 /*
1550 * The initiator shall then wait at least two deskew delays and release
1551 * the BSY signal.
1552 */
1553 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1554
1555 /* Reset BSY */
1556 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA |
1557 ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1558
1559 /*
1560 * Something weird happens when we cease to drive BSY - looks
1561 * like the board/chip is letting us do another read before the
1562 * appropriate propagation delay has expired, and we're confusing
1563 * a BSY signal from ourselves as the target's response to SELECTION.
1564 *
1565 * A small delay (the 'C++' frontend breaks the pipeline with an
1566 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1567 * tighter 'C' code breaks and requires this) solves the problem -
1568 * the 1 us delay is arbitrary, and only used because this delay will
1569 * be the same on other platforms and since it works here, it should
1570 * work there.
1571 *
1572 * wingel suggests that this could be due to failing to wait
1573 * one deskew delay.
1574 */
1575
1576 udelay(1);
1577
1578 SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
1579
1580 /*
1581 * The SCSI specification calls for a 250 ms timeout for the actual
1582 * selection.
1583 */
1584
1585 timeout = jiffies + 25;
1586
1587 /*
1588 * XXX very interesting - we're seeing a bounce where the BSY we
1589 * asserted is being reflected / still asserted (propagation delay?)
1590 * and it's detecting as true. Sigh.
1591 */
1592
1593#if 0
1594 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1595 * IO while SEL is true. But again, there are some disks out the in the
1596 * world that do that nevertheless. (Somebody claimed that this announces
1597 * reselection capability of the target.) So we better skip that test and
1598 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-)
1599 */
1600
1601 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) &
1602 (SR_BSY | SR_IO)));
1603
1604 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) ==
1605 (SR_SEL | SR_IO)) {
1606 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1607 NCR5380_reselect(instance);
1608 printk (KERN_ERR "scsi%d: reselection after won arbitration?\n",
1609 HOSTNO);
1610 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1611 return -1;
1612 }
1613#else
1614 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY));
1615#endif
1616
1617 /*
1618 * No less than two deskew delays after the initiator detects the
1619 * BSY signal is true, it shall release the SEL signal and may
1620 * change the DATA BUS. -wingel
1621 */
1622
1623 udelay(1);
1624
1625 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1626
1627 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1628 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1629 if (hostdata->targets_present & (1 << cmd->device->id)) {
1630 printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO);
1631 if (hostdata->restart_select)
1632 printk(KERN_NOTICE "\trestart select\n");
1633 NCR_PRINT(NDEBUG_ANY);
1634 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1635 return -1;
1636 }
1637 cmd->result = DID_BAD_TARGET << 16;
1638#ifdef NCR5380_STATS
1639 collect_stats(hostdata, cmd);
1640#endif
1641#ifdef SUPPORT_TAGS
1642 cmd_free_tag( cmd );
1643#endif
1644 cmd->scsi_done(cmd);
1645 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1646 SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO);
1647 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1648 return 0;
1649 }
1650
1651 hostdata->targets_present |= (1 << cmd->device->id);
1652
1653 /*
1654 * Since we followed the SCSI spec, and raised ATN while SEL
1655 * was true but before BSY was false during selection, the information
1656 * transfer phase should be a MESSAGE OUT phase so that we can send the
1657 * IDENTIFY message.
1658 *
1659 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1660 * message (2 bytes) with a tag ID that we increment with every command
1661 * until it wraps back to 0.
1662 *
1663 * XXX - it turns out that there are some broken SCSI-II devices,
1664 * which claim to support tagged queuing but fail when more than
1665 * some number of commands are issued at once.
1666 */
1667
1668 /* Wait for start of REQ/ACK handshake */
1669 while (!(NCR5380_read(STATUS_REG) & SR_REQ));
1670
1671 SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1672 HOSTNO, cmd->device->id);
1673 tmp[0] = IDENTIFY(1, cmd->device->lun);
1674
1675#ifdef SUPPORT_TAGS
1676 if (cmd->tag != TAG_NONE) {
1677 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
1678 tmp[2] = cmd->tag;
1679 len = 3;
1680 } else
1681 len = 1;
1682#else
1683 len = 1;
1684 cmd->tag=0;
1685#endif /* SUPPORT_TAGS */
1686
1687 /* Send message(s) */
1688 data = tmp;
1689 phase = PHASE_MSGOUT;
1690 NCR5380_transfer_pio(instance, &phase, &len, &data);
1691 SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO);
1692 /* XXX need to handle errors here */
1693 hostdata->connected = cmd;
1694#ifndef SUPPORT_TAGS
1695 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1696#endif
1697
1698 initialize_SCp(cmd);
1699
1700
1701 return 0;
1702}
1703
1704/*
1705 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1706 * unsigned char *phase, int *count, unsigned char **data)
1707 *
1708 * Purpose : transfers data in given phase using polled I/O
1709 *
1710 * Inputs : instance - instance of driver, *phase - pointer to
1711 * what phase is expected, *count - pointer to number of
1712 * bytes to transfer, **data - pointer to data pointer.
1713 *
1714 * Returns : -1 when different phase is entered without transferring
1715 * maximum number of bytes, 0 if all bytes are transfered or exit
1716 * is in same phase.
1717 *
1718 * Also, *phase, *count, *data are modified in place.
1719 *
1720 * XXX Note : handling for bus free may be useful.
1721 */
1722
1723/*
1724 * Note : this code is not as quick as it could be, however it
1725 * IS 100% reliable, and for the actual data transfer where speed
1726 * counts, we will always do a pseudo DMA or DMA transfer.
1727 */
1728
1729static int NCR5380_transfer_pio( struct Scsi_Host *instance,
1730 unsigned char *phase, int *count,
1731 unsigned char **data)
1732{
1733 register unsigned char p = *phase, tmp;
1734 register int c = *count;
1735 register unsigned char *d = *data;
1736
1737 /*
1738 * The NCR5380 chip will only drive the SCSI bus when the
1739 * phase specified in the appropriate bits of the TARGET COMMAND
1740 * REGISTER match the STATUS REGISTER
1741 */
1742
1743 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1744
1745 do {
1746 /*
1747 * Wait for assertion of REQ, after which the phase bits will be
1748 * valid
1749 */
1750 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ));
1751
1752 HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO);
1753
1754 /* Check for phase mismatch */
1755 if ((tmp & PHASE_MASK) != p) {
1756 PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO);
1757 NCR_PRINT_PHASE(NDEBUG_PIO);
1758 break;
1759 }
1760
1761 /* Do actual transfer from SCSI bus to / from memory */
1762 if (!(p & SR_IO))
1763 NCR5380_write(OUTPUT_DATA_REG, *d);
1764 else
1765 *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1766
1767 ++d;
1768
1769 /*
1770 * The SCSI standard suggests that in MSGOUT phase, the initiator
1771 * should drop ATN on the last byte of the message phase
1772 * after REQ has been asserted for the handshake but before
1773 * the initiator raises ACK.
1774 */
1775
1776 if (!(p & SR_IO)) {
1777 if (!((p & SR_MSG) && c > 1)) {
1778 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1779 ICR_ASSERT_DATA);
1780 NCR_PRINT(NDEBUG_PIO);
1781 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1782 ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1783 } else {
1784 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1785 ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1786 NCR_PRINT(NDEBUG_PIO);
1787 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1788 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1789 }
1790 } else {
1791 NCR_PRINT(NDEBUG_PIO);
1792 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1793 }
1794
1795 while (NCR5380_read(STATUS_REG) & SR_REQ);
1796
1797 HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO);
1798
1799/*
1800 * We have several special cases to consider during REQ/ACK handshaking :
1801 * 1. We were in MSGOUT phase, and we are on the last byte of the
1802 * message. ATN must be dropped as ACK is dropped.
1803 *
1804 * 2. We are in a MSGIN phase, and we are on the last byte of the
1805 * message. We must exit with ACK asserted, so that the calling
1806 * code may raise ATN before dropping ACK to reject the message.
1807 *
1808 * 3. ACK and ATN are clear and the target may proceed as normal.
1809 */
1810 if (!(p == PHASE_MSGIN && c == 1)) {
1811 if (p == PHASE_MSGOUT && c > 1)
1812 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1813 else
1814 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1815 }
1816 } while (--c);
1817
1818 PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c);
1819
1820 *count = c;
1821 *data = d;
1822 tmp = NCR5380_read(STATUS_REG);
1823 /* The phase read from the bus is valid if either REQ is (already)
1824 * asserted or if ACK hasn't been released yet. The latter is the case if
1825 * we're in MSGIN and all wanted bytes have been received. */
1826 if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
1827 *phase = tmp & PHASE_MASK;
1828 else
1829 *phase = PHASE_UNKNOWN;
1830
1831 if (!c || (*phase == p))
1832 return 0;
1833 else
1834 return -1;
1835}
1836
1837/*
1838 * Function : do_abort (Scsi_Host *host)
1839 *
1840 * Purpose : abort the currently established nexus. Should only be
1841 * called from a routine which can drop into a
1842 *
1843 * Returns : 0 on success, -1 on failure.
1844 */
1845
1846static int do_abort (struct Scsi_Host *host)
1847{
1848 unsigned char tmp, *msgptr, phase;
1849 int len;
1850
1851 /* Request message out phase */
1852 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1853
1854 /*
1855 * Wait for the target to indicate a valid phase by asserting
1856 * REQ. Once this happens, we'll have either a MSGOUT phase
1857 * and can immediately send the ABORT message, or we'll have some
1858 * other phase and will have to source/sink data.
1859 *
1860 * We really don't care what value was on the bus or what value
1861 * the target sees, so we just handshake.
1862 */
1863
1864 while (!(tmp = NCR5380_read(STATUS_REG)) & SR_REQ);
1865
1866 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1867
1868 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1869 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
1870 ICR_ASSERT_ACK);
1871 while (NCR5380_read(STATUS_REG) & SR_REQ);
1872 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1873 }
1874
1875 tmp = ABORT;
1876 msgptr = &tmp;
1877 len = 1;
1878 phase = PHASE_MSGOUT;
1879 NCR5380_transfer_pio (host, &phase, &len, &msgptr);
1880
1881 /*
1882 * If we got here, and the command completed successfully,
1883 * we're about to go into bus free state.
1884 */
1885
1886 return len ? -1 : 0;
1887}
1888
1889#if defined(REAL_DMA)
1890/*
1891 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1892 * unsigned char *phase, int *count, unsigned char **data)
1893 *
1894 * Purpose : transfers data in given phase using either real
1895 * or pseudo DMA.
1896 *
1897 * Inputs : instance - instance of driver, *phase - pointer to
1898 * what phase is expected, *count - pointer to number of
1899 * bytes to transfer, **data - pointer to data pointer.
1900 *
1901 * Returns : -1 when different phase is entered without transferring
1902 * maximum number of bytes, 0 if all bytes or transfered or exit
1903 * is in same phase.
1904 *
1905 * Also, *phase, *count, *data are modified in place.
1906 *
1907 */
1908
1909
1910static int NCR5380_transfer_dma( struct Scsi_Host *instance,
1911 unsigned char *phase, int *count,
1912 unsigned char **data)
1913{
1914 SETUP_HOSTDATA(instance);
1915 register int c = *count;
1916 register unsigned char p = *phase;
1917 register unsigned char *d = *data;
1918 unsigned char tmp;
1919 unsigned long flags;
1920
1921 if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1922 *phase = tmp;
1923 return -1;
1924 }
1925
1926 if (atari_read_overruns && (p & SR_IO)) {
1927 c -= atari_read_overruns;
1928 }
1929
1930 DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1931 HOSTNO, (p & SR_IO) ? "reading" : "writing",
1932 c, (p & SR_IO) ? "to" : "from", d);
1933
1934 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1935
1936#ifdef REAL_DMA
1937 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1938#endif /* def REAL_DMA */
1939
1940 if (IS_A_TT()) {
1941 /* On the Medusa, it is a must to initialize the DMA before
1942 * starting the NCR. This is also the cleaner way for the TT.
1943 */
1944 local_irq_save(flags);
1945 hostdata->dma_len = (p & SR_IO) ?
1946 NCR5380_dma_read_setup(instance, d, c) :
1947 NCR5380_dma_write_setup(instance, d, c);
1948 local_irq_restore(flags);
1949 }
1950
1951 if (p & SR_IO)
1952 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1953 else {
1954 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1955 NCR5380_write(START_DMA_SEND_REG, 0);
1956 }
1957
1958 if (!IS_A_TT()) {
1959 /* On the Falcon, the DMA setup must be done after the last */
1960 /* NCR access, else the DMA setup gets trashed!
1961 */
1962 local_irq_save(flags);
1963 hostdata->dma_len = (p & SR_IO) ?
1964 NCR5380_dma_read_setup(instance, d, c) :
1965 NCR5380_dma_write_setup(instance, d, c);
1966 local_irq_restore(flags);
1967 }
1968 return 0;
1969}
1970#endif /* defined(REAL_DMA) */
1971
1972/*
1973 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1974 *
1975 * Purpose : run through the various SCSI phases and do as the target
1976 * directs us to. Operates on the currently connected command,
1977 * instance->connected.
1978 *
1979 * Inputs : instance, instance for which we are doing commands
1980 *
1981 * Side effects : SCSI things happen, the disconnected queue will be
1982 * modified if a command disconnects, *instance->connected will
1983 * change.
1984 *
1985 * XXX Note : we need to watch for bus free or a reset condition here
1986 * to recover from an unexpected bus free condition.
1987 */
1988
1989static void NCR5380_information_transfer (struct Scsi_Host *instance)
1990{
1991 SETUP_HOSTDATA(instance);
1992 unsigned long flags;
1993 unsigned char msgout = NOP;
1994 int sink = 0;
1995 int len;
1996#if defined(REAL_DMA)
1997 int transfersize;
1998#endif
1999 unsigned char *data;
2000 unsigned char phase, tmp, extended_msg[10], old_phase=0xff;
2001 Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2002
2003 while (1) {
2004 tmp = NCR5380_read(STATUS_REG);
2005 /* We only have a valid SCSI phase when REQ is asserted */
2006 if (tmp & SR_REQ) {
2007 phase = (tmp & PHASE_MASK);
2008 if (phase != old_phase) {
2009 old_phase = phase;
2010 NCR_PRINT_PHASE(NDEBUG_INFORMATION);
2011 }
2012
2013 if (sink && (phase != PHASE_MSGOUT)) {
2014 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2015
2016 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
2017 ICR_ASSERT_ACK);
2018 while (NCR5380_read(STATUS_REG) & SR_REQ);
2019 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2020 ICR_ASSERT_ATN);
2021 sink = 0;
2022 continue;
2023 }
2024
2025 switch (phase) {
2026 case PHASE_DATAOUT:
2027#if (NDEBUG & NDEBUG_NO_DATAOUT)
2028 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2029 "aborted\n", HOSTNO);
2030 sink = 1;
2031 do_abort(instance);
2032 cmd->result = DID_ERROR << 16;
2033 cmd->done(cmd);
2034 return;
2035#endif
2036 case PHASE_DATAIN:
2037 /*
2038 * If there is no room left in the current buffer in the
2039 * scatter-gather list, move onto the next one.
2040 */
2041
2042 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2043 ++cmd->SCp.buffer;
2044 --cmd->SCp.buffers_residual;
2045 cmd->SCp.this_residual = cmd->SCp.buffer->length;
2046 cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+
2047 cmd->SCp.buffer->offset;
2048 /* ++roman: Try to merge some scatter-buffers if
2049 * they are at contiguous physical addresses.
2050 */
2051 merge_contiguous_buffers( cmd );
2052 INF_PRINTK("scsi%d: %d bytes and %d buffers left\n",
2053 HOSTNO, cmd->SCp.this_residual,
2054 cmd->SCp.buffers_residual);
2055 }
2056
2057 /*
2058 * The preferred transfer method is going to be
2059 * PSEUDO-DMA for systems that are strictly PIO,
2060 * since we can let the hardware do the handshaking.
2061 *
2062 * For this to work, we need to know the transfersize
2063 * ahead of time, since the pseudo-DMA code will sit
2064 * in an unconditional loop.
2065 */
2066
2067/* ++roman: I suggest, this should be
2068 * #if def(REAL_DMA)
2069 * instead of leaving REAL_DMA out.
2070 */
2071
2072#if defined(REAL_DMA)
2073 if (!cmd->device->borken &&
2074 (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) {
2075 len = transfersize;
2076 cmd->SCp.phase = phase;
2077 if (NCR5380_transfer_dma(instance, &phase,
2078 &len, (unsigned char **) &cmd->SCp.ptr)) {
2079 /*
2080 * If the watchdog timer fires, all future
2081 * accesses to this device will use the
2082 * polled-IO. */
2083 printk(KERN_NOTICE "scsi%d: switching target %d "
2084 "lun %d to slow handshake\n", HOSTNO,
2085 cmd->device->id, cmd->device->lun);
2086 cmd->device->borken = 1;
2087 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2088 ICR_ASSERT_ATN);
2089 sink = 1;
2090 do_abort(instance);
2091 cmd->result = DID_ERROR << 16;
2092 cmd->done(cmd);
2093 /* XXX - need to source or sink data here, as appropriate */
2094 } else {
2095#ifdef REAL_DMA
2096 /* ++roman: When using real DMA,
2097 * information_transfer() should return after
2098 * starting DMA since it has nothing more to
2099 * do.
2100 */
2101 return;
2102#else
2103 cmd->SCp.this_residual -= transfersize - len;
2104#endif
2105 }
2106 } else
2107#endif /* defined(REAL_DMA) */
2108 NCR5380_transfer_pio(instance, &phase,
2109 (int *) &cmd->SCp.this_residual, (unsigned char **)
2110 &cmd->SCp.ptr);
2111 break;
2112 case PHASE_MSGIN:
2113 len = 1;
2114 data = &tmp;
2115 NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */
2116 NCR5380_transfer_pio(instance, &phase, &len, &data);
2117 cmd->SCp.Message = tmp;
2118
2119 switch (tmp) {
2120 /*
2121 * Linking lets us reduce the time required to get the
2122 * next command out to the device, hopefully this will
2123 * mean we don't waste another revolution due to the delays
2124 * required by ARBITRATION and another SELECTION.
2125 *
2126 * In the current implementation proposal, low level drivers
2127 * merely have to start the next command, pointed to by
2128 * next_link, done() is called as with unlinked commands.
2129 */
2130#ifdef LINKED
2131 case LINKED_CMD_COMPLETE:
2132 case LINKED_FLG_CMD_COMPLETE:
2133 /* Accept message by clearing ACK */
2134 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2135
2136 LNK_PRINTK("scsi%d: target %d lun %d linked command "
2137 "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun);
2138
2139 /* Enable reselect interrupts */
2140 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2141 /*
2142 * Sanity check : A linked command should only terminate
2143 * with one of these messages if there are more linked
2144 * commands available.
2145 */
2146
2147 if (!cmd->next_link) {
2148 printk(KERN_NOTICE "scsi%d: target %d lun %d "
2149 "linked command complete, no next_link\n",
2150 HOSTNO, cmd->device->id, cmd->device->lun);
2151 sink = 1;
2152 do_abort (instance);
2153 return;
2154 }
2155
2156 initialize_SCp(cmd->next_link);
2157 /* The next command is still part of this process; copy it
2158 * and don't free it! */
2159 cmd->next_link->tag = cmd->tag;
2160 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2161 LNK_PRINTK("scsi%d: target %d lun %d linked request "
2162 "done, calling scsi_done().\n",
2163 HOSTNO, cmd->device->id, cmd->device->lun);
2164#ifdef NCR5380_STATS
2165 collect_stats(hostdata, cmd);
2166#endif
2167 cmd->scsi_done(cmd);
2168 cmd = hostdata->connected;
2169 break;
2170#endif /* def LINKED */
2171 case ABORT:
2172 case COMMAND_COMPLETE:
2173 /* Accept message by clearing ACK */
2174 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2175 /* ++guenther: possible race with Falcon locking */
2176 falcon_dont_release++;
2177 hostdata->connected = NULL;
2178 QU_PRINTK("scsi%d: command for target %d, lun %d "
2179 "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
2180#ifdef SUPPORT_TAGS
2181 cmd_free_tag( cmd );
2182 if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
2183 /* Turn a QUEUE FULL status into BUSY, I think the
2184 * mid level cannot handle QUEUE FULL :-( (The
2185 * command is retried after BUSY). Also update our
2186 * queue size to the number of currently issued
2187 * commands now.
2188 */
2189 /* ++Andreas: the mid level code knows about
2190 QUEUE_FULL now. */
2191 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
2192 TAG_PRINTK("scsi%d: target %d lun %d returned "
2193 "QUEUE_FULL after %d commands\n",
2194 HOSTNO, cmd->device->id, cmd->device->lun,
2195 ta->nr_allocated);
2196 if (ta->queue_size > ta->nr_allocated)
2197 ta->nr_allocated = ta->queue_size;
2198 }
2199#else
2200 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2201#endif
2202 /* Enable reselect interrupts */
2203 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2204
2205 /*
2206 * I'm not sure what the correct thing to do here is :
2207 *
2208 * If the command that just executed is NOT a request
2209 * sense, the obvious thing to do is to set the result
2210 * code to the values of the stored parameters.
2211 *
2212 * If it was a REQUEST SENSE command, we need some way to
2213 * differentiate between the failure code of the original
2214 * and the failure code of the REQUEST sense - the obvious
2215 * case is success, where we fall through and leave the
2216 * result code unchanged.
2217 *
2218 * The non-obvious place is where the REQUEST SENSE failed
2219 */
2220
2221 if (cmd->cmnd[0] != REQUEST_SENSE)
2222 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2223 else if (status_byte(cmd->SCp.Status) != GOOD)
2224 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2225
2226#ifdef AUTOSENSE
2227 if ((cmd->cmnd[0] != REQUEST_SENSE) &&
2228 (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2229 ASEN_PRINTK("scsi%d: performing request sense\n",
2230 HOSTNO);
2231 cmd->cmnd[0] = REQUEST_SENSE;
2232 cmd->cmnd[1] &= 0xe0;
2233 cmd->cmnd[2] = 0;
2234 cmd->cmnd[3] = 0;
2235 cmd->cmnd[4] = sizeof(cmd->sense_buffer);
2236 cmd->cmnd[5] = 0;
2237 cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]);
2238
2239 cmd->use_sg = 0;
2240 /* this is initialized from initialize_SCp
2241 cmd->SCp.buffer = NULL;
2242 cmd->SCp.buffers_residual = 0;
2243 */
2244 cmd->request_buffer = (char *) cmd->sense_buffer;
2245 cmd->request_bufflen = sizeof(cmd->sense_buffer);
2246
2247 local_irq_save(flags);
2248 LIST(cmd,hostdata->issue_queue);
2249 NEXT(cmd) = hostdata->issue_queue;
2250 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2251 local_irq_restore(flags);
2252 QU_PRINTK("scsi%d: REQUEST SENSE added to head of "
2253 "issue queue\n", H_NO(cmd));
2254 } else
2255#endif /* def AUTOSENSE */
2256 {
2257#ifdef NCR5380_STATS
2258 collect_stats(hostdata, cmd);
2259#endif
2260 cmd->scsi_done(cmd);
2261 }
2262
2263 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2264 /*
2265 * Restore phase bits to 0 so an interrupted selection,
2266 * arbitration can resume.
2267 */
2268 NCR5380_write(TARGET_COMMAND_REG, 0);
2269
2270 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2271 barrier();
2272
2273 falcon_dont_release--;
2274 /* ++roman: For Falcon SCSI, release the lock on the
2275 * ST-DMA here if no other commands are waiting on the
2276 * disconnected queue.
2277 */
2278 falcon_release_lock_if_possible( hostdata );
2279 return;
2280 case MESSAGE_REJECT:
2281 /* Accept message by clearing ACK */
2282 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2283 /* Enable reselect interrupts */
2284 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2285 switch (hostdata->last_message) {
2286 case HEAD_OF_QUEUE_TAG:
2287 case ORDERED_QUEUE_TAG:
2288 case SIMPLE_QUEUE_TAG:
2289 /* The target obviously doesn't support tagged
2290 * queuing, even though it announced this ability in
2291 * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2292 * clear 'tagged_supported' and lock the LUN, since
2293 * the command is treated as untagged further on.
2294 */
2295 cmd->device->tagged_supported = 0;
2296 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2297 cmd->tag = TAG_NONE;
2298 TAG_PRINTK("scsi%d: target %d lun %d rejected "
2299 "QUEUE_TAG message; tagged queuing "
2300 "disabled\n",
2301 HOSTNO, cmd->device->id, cmd->device->lun);
2302 break;
2303 }
2304 break;
2305 case DISCONNECT:
2306 /* Accept message by clearing ACK */
2307 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2308 local_irq_save(flags);
2309 cmd->device->disconnect = 1;
2310 LIST(cmd,hostdata->disconnected_queue);
2311 NEXT(cmd) = hostdata->disconnected_queue;
2312 hostdata->connected = NULL;
2313 hostdata->disconnected_queue = cmd;
2314 local_irq_restore(flags);
2315 QU_PRINTK("scsi%d: command for target %d lun %d was "
2316 "moved from connected to the "
2317 "disconnected_queue\n", HOSTNO,
2318 cmd->device->id, cmd->device->lun);
2319 /*
2320 * Restore phase bits to 0 so an interrupted selection,
2321 * arbitration can resume.
2322 */
2323 NCR5380_write(TARGET_COMMAND_REG, 0);
2324
2325 /* Enable reselect interrupts */
2326 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2327 /* Wait for bus free to avoid nasty timeouts */
2328 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2329 barrier();
2330 return;
2331 /*
2332 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2333 * operation, in violation of the SCSI spec so we can safely
2334 * ignore SAVE/RESTORE pointers calls.
2335 *
2336 * Unfortunately, some disks violate the SCSI spec and
2337 * don't issue the required SAVE_POINTERS message before
2338 * disconnecting, and we have to break spec to remain
2339 * compatible.
2340 */
2341 case SAVE_POINTERS:
2342 case RESTORE_POINTERS:
2343 /* Accept message by clearing ACK */
2344 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2345 /* Enable reselect interrupts */
2346 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2347 break;
2348 case EXTENDED_MESSAGE:
2349/*
2350 * Extended messages are sent in the following format :
2351 * Byte
2352 * 0 EXTENDED_MESSAGE == 1
2353 * 1 length (includes one byte for code, doesn't
2354 * include first two bytes)
2355 * 2 code
2356 * 3..length+1 arguments
2357 *
2358 * Start the extended message buffer with the EXTENDED_MESSAGE
Matthew Wilcox1abfd372005-12-15 16:22:01 -05002359 * byte, since spi_print_msg() wants the whole thing.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002360 */
2361 extended_msg[0] = EXTENDED_MESSAGE;
2362 /* Accept first byte by clearing ACK */
2363 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2364
2365 EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO);
2366
2367 len = 2;
2368 data = extended_msg + 1;
2369 phase = PHASE_MSGIN;
2370 NCR5380_transfer_pio(instance, &phase, &len, &data);
2371 EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2372 (int)extended_msg[1], (int)extended_msg[2]);
2373
2374 if (!len && extended_msg[1] <=
2375 (sizeof (extended_msg) - 1)) {
2376 /* Accept third byte by clearing ACK */
2377 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2378 len = extended_msg[1] - 1;
2379 data = extended_msg + 3;
2380 phase = PHASE_MSGIN;
2381
2382 NCR5380_transfer_pio(instance, &phase, &len, &data);
2383 EXT_PRINTK("scsi%d: message received, residual %d\n",
2384 HOSTNO, len);
2385
2386 switch (extended_msg[2]) {
2387 case EXTENDED_SDTR:
2388 case EXTENDED_WDTR:
2389 case EXTENDED_MODIFY_DATA_POINTER:
2390 case EXTENDED_EXTENDED_IDENTIFY:
2391 tmp = 0;
2392 }
2393 } else if (len) {
2394 printk(KERN_NOTICE "scsi%d: error receiving "
2395 "extended message\n", HOSTNO);
2396 tmp = 0;
2397 } else {
2398 printk(KERN_NOTICE "scsi%d: extended message "
2399 "code %02x length %d is too long\n",
2400 HOSTNO, extended_msg[2], extended_msg[1]);
2401 tmp = 0;
2402 }
2403 /* Fall through to reject message */
2404
2405 /*
2406 * If we get something weird that we aren't expecting,
2407 * reject it.
2408 */
2409 default:
2410 if (!tmp) {
2411 printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO);
Matthew Wilcox1abfd372005-12-15 16:22:01 -05002412 spi_print_msg(extended_msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002413 printk("\n");
2414 } else if (tmp != EXTENDED_MESSAGE)
2415 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2416 "message %02x from target %d, lun %d\n",
2417 HOSTNO, tmp, cmd->device->id, cmd->device->lun);
2418 else
2419 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2420 "extended message "
2421 "code %02x, length %d from target %d, lun %d\n",
2422 HOSTNO, extended_msg[1], extended_msg[0],
2423 cmd->device->id, cmd->device->lun);
2424
2425
2426 msgout = MESSAGE_REJECT;
2427 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2428 ICR_ASSERT_ATN);
2429 break;
2430 } /* switch (tmp) */
2431 break;
2432 case PHASE_MSGOUT:
2433 len = 1;
2434 data = &msgout;
2435 hostdata->last_message = msgout;
2436 NCR5380_transfer_pio(instance, &phase, &len, &data);
2437 if (msgout == ABORT) {
2438#ifdef SUPPORT_TAGS
2439 cmd_free_tag( cmd );
2440#else
2441 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2442#endif
2443 hostdata->connected = NULL;
2444 cmd->result = DID_ERROR << 16;
2445#ifdef NCR5380_STATS
2446 collect_stats(hostdata, cmd);
2447#endif
2448 cmd->scsi_done(cmd);
2449 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2450 falcon_release_lock_if_possible( hostdata );
2451 return;
2452 }
2453 msgout = NOP;
2454 break;
2455 case PHASE_CMDOUT:
2456 len = cmd->cmd_len;
2457 data = cmd->cmnd;
2458 /*
2459 * XXX for performance reasons, on machines with a
2460 * PSEUDO-DMA architecture we should probably
2461 * use the dma transfer function.
2462 */
2463 NCR5380_transfer_pio(instance, &phase, &len,
2464 &data);
2465 break;
2466 case PHASE_STATIN:
2467 len = 1;
2468 data = &tmp;
2469 NCR5380_transfer_pio(instance, &phase, &len, &data);
2470 cmd->SCp.Status = tmp;
2471 break;
2472 default:
2473 printk("scsi%d: unknown phase\n", HOSTNO);
2474 NCR_PRINT(NDEBUG_ANY);
2475 } /* switch(phase) */
2476 } /* if (tmp * SR_REQ) */
2477 } /* while (1) */
2478}
2479
2480/*
2481 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2482 *
2483 * Purpose : does reselection, initializing the instance->connected
2484 * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2485 * nexus has been reestablished,
2486 *
2487 * Inputs : instance - this instance of the NCR5380.
2488 *
2489 */
2490
2491
2492static void NCR5380_reselect (struct Scsi_Host *instance)
2493{
2494 SETUP_HOSTDATA(instance);
2495 unsigned char target_mask;
2496 unsigned char lun, phase;
2497 int len;
2498#ifdef SUPPORT_TAGS
2499 unsigned char tag;
2500#endif
2501 unsigned char msg[3];
2502 unsigned char *data;
2503 Scsi_Cmnd *tmp = NULL, *prev;
2504/* unsigned long flags; */
2505
2506 /*
2507 * Disable arbitration, etc. since the host adapter obviously
2508 * lost, and tell an interrupted NCR5380_select() to restart.
2509 */
2510
2511 NCR5380_write(MODE_REG, MR_BASE);
2512 hostdata->restart_select = 1;
2513
2514 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2515
2516 RSL_PRINTK("scsi%d: reselect\n", HOSTNO);
2517
2518 /*
2519 * At this point, we have detected that our SCSI ID is on the bus,
2520 * SEL is true and BSY was false for at least one bus settle delay
2521 * (400 ns).
2522 *
2523 * We must assert BSY ourselves, until the target drops the SEL
2524 * signal.
2525 */
2526
2527 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2528
2529 while (NCR5380_read(STATUS_REG) & SR_SEL);
2530 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2531
2532 /*
2533 * Wait for target to go into MSGIN.
2534 */
2535
2536 while (!(NCR5380_read(STATUS_REG) & SR_REQ));
2537
2538 len = 1;
2539 data = msg;
2540 phase = PHASE_MSGIN;
2541 NCR5380_transfer_pio(instance, &phase, &len, &data);
2542
2543 if (!(msg[0] & 0x80)) {
2544 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
Matthew Wilcox1abfd372005-12-15 16:22:01 -05002545 spi_print_msg(msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002546 do_abort(instance);
2547 return;
2548 }
2549 lun = (msg[0] & 0x07);
2550
2551#ifdef SUPPORT_TAGS
2552 /* If the phase is still MSGIN, the target wants to send some more
2553 * messages. In case it supports tagged queuing, this is probably a
2554 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2555 */
2556 tag = TAG_NONE;
2557 if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
2558 /* Accept previous IDENTIFY message by clearing ACK */
2559 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE );
2560 len = 2;
2561 data = msg+1;
2562 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2563 msg[1] == SIMPLE_QUEUE_TAG)
2564 tag = msg[2];
2565 TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at "
2566 "reselection\n", HOSTNO, target_mask, lun, tag);
2567 }
2568#endif
2569
2570 /*
2571 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2572 * just reestablished, and remove it from the disconnected queue.
2573 */
2574
2575 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL;
2576 tmp; prev = tmp, tmp = NEXT(tmp) ) {
2577 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2578#ifdef SUPPORT_TAGS
2579 && (tag == tmp->tag)
2580#endif
2581 ) {
2582 /* ++guenther: prevent race with falcon_release_lock */
2583 falcon_dont_release++;
2584 if (prev) {
2585 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2586 NEXT(prev) = NEXT(tmp);
2587 } else {
2588 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
2589 hostdata->disconnected_queue = NEXT(tmp);
2590 }
2591 NEXT(tmp) = NULL;
2592 break;
2593 }
2594 }
2595
2596 if (!tmp) {
2597 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
2598#ifdef SUPPORT_TAGS
2599 "tag %d "
2600#endif
2601 "not in disconnected_queue.\n",
2602 HOSTNO, target_mask, lun
2603#ifdef SUPPORT_TAGS
2604 , tag
2605#endif
2606 );
2607 /*
2608 * Since we have an established nexus that we can't do anything
2609 * with, we must abort it.
2610 */
2611 do_abort(instance);
2612 return;
2613 }
2614
2615 /* Accept message by clearing ACK */
2616 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2617
2618 hostdata->connected = tmp;
2619 RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n",
2620 HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
2621 falcon_dont_release--;
2622}
2623
2624
2625/*
2626 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2627 *
2628 * Purpose : abort a command
2629 *
2630 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2631 * host byte of the result field to, if zero DID_ABORTED is
2632 * used.
2633 *
2634 * Returns : 0 - success, -1 on failure.
2635 *
2636 * XXX - there is no way to abort the command that is currently
2637 * connected, you have to wait for it to complete. If this is
2638 * a problem, we could implement longjmp() / setjmp(), setjmp()
2639 * called where the loop started in NCR5380_main().
2640 */
2641
2642static
2643int NCR5380_abort (Scsi_Cmnd *cmd)
2644{
2645 struct Scsi_Host *instance = cmd->device->host;
2646 SETUP_HOSTDATA(instance);
2647 Scsi_Cmnd *tmp, **prev;
2648 unsigned long flags;
2649
2650 printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO);
db9dff32005-04-03 14:53:59 -05002651 scsi_print_command(cmd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002652
2653 NCR5380_print_status (instance);
2654
2655 local_irq_save(flags);
2656
2657 if (!IS_A_TT() && !falcon_got_lock)
2658 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n",
2659 HOSTNO);
2660
2661 ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2662 NCR5380_read(BUS_AND_STATUS_REG),
2663 NCR5380_read(STATUS_REG));
2664
2665#if 1
2666/*
2667 * Case 1 : If the command is the currently executing command,
2668 * we'll set the aborted flag and return control so that
2669 * information transfer routine can exit cleanly.
2670 */
2671
2672 if (hostdata->connected == cmd) {
2673
2674 ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO);
2675/*
2676 * We should perform BSY checking, and make sure we haven't slipped
2677 * into BUS FREE.
2678 */
2679
2680/* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2681/*
2682 * Since we can't change phases until we've completed the current
2683 * handshake, we have to source or sink a byte of data if the current
2684 * phase is not MSGOUT.
2685 */
2686
2687/*
2688 * Return control to the executing NCR drive so we can clear the
2689 * aborted flag and get back into our main loop.
2690 */
2691
2692 if (do_abort(instance) == 0) {
2693 hostdata->aborted = 1;
2694 hostdata->connected = NULL;
2695 cmd->result = DID_ABORT << 16;
2696#ifdef SUPPORT_TAGS
2697 cmd_free_tag( cmd );
2698#else
2699 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2700#endif
2701 local_irq_restore(flags);
2702 cmd->scsi_done(cmd);
2703 falcon_release_lock_if_possible( hostdata );
2704 return SCSI_ABORT_SUCCESS;
2705 } else {
2706/* local_irq_restore(flags); */
2707 printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2708 return SCSI_ABORT_ERROR;
2709 }
2710 }
2711#endif
2712
2713/*
2714 * Case 2 : If the command hasn't been issued yet, we simply remove it
2715 * from the issue queue.
2716 */
2717 for (prev = (Scsi_Cmnd **) &(hostdata->issue_queue),
2718 tmp = (Scsi_Cmnd *) hostdata->issue_queue;
2719 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) )
2720 if (cmd == tmp) {
2721 REMOVE(5, *prev, tmp, NEXT(tmp));
2722 (*prev) = NEXT(tmp);
2723 NEXT(tmp) = NULL;
2724 tmp->result = DID_ABORT << 16;
2725 local_irq_restore(flags);
2726 ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n",
2727 HOSTNO);
2728 /* Tagged queuing note: no tag to free here, hasn't been assigned
2729 * yet... */
2730 tmp->scsi_done(tmp);
2731 falcon_release_lock_if_possible( hostdata );
2732 return SCSI_ABORT_SUCCESS;
2733 }
2734
2735/*
2736 * Case 3 : If any commands are connected, we're going to fail the abort
2737 * and let the high level SCSI driver retry at a later time or
2738 * issue a reset.
2739 *
2740 * Timeouts, and therefore aborted commands, will be highly unlikely
2741 * and handling them cleanly in this situation would make the common
2742 * case of noresets less efficient, and would pollute our code. So,
2743 * we fail.
2744 */
2745
2746 if (hostdata->connected) {
2747 local_irq_restore(flags);
2748 ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO);
2749 return SCSI_ABORT_SNOOZE;
2750 }
2751
2752/*
2753 * Case 4: If the command is currently disconnected from the bus, and
2754 * there are no connected commands, we reconnect the I_T_L or
2755 * I_T_L_Q nexus associated with it, go into message out, and send
2756 * an abort message.
2757 *
2758 * This case is especially ugly. In order to reestablish the nexus, we
2759 * need to call NCR5380_select(). The easiest way to implement this
2760 * function was to abort if the bus was busy, and let the interrupt
2761 * handler triggered on the SEL for reselect take care of lost arbitrations
2762 * where necessary, meaning interrupts need to be enabled.
2763 *
2764 * When interrupts are enabled, the queues may change - so we
2765 * can't remove it from the disconnected queue before selecting it
2766 * because that could cause a failure in hashing the nexus if that
2767 * device reselected.
2768 *
2769 * Since the queues may change, we can't use the pointers from when we
2770 * first locate it.
2771 *
2772 * So, we must first locate the command, and if NCR5380_select()
2773 * succeeds, then issue the abort, relocate the command and remove
2774 * it from the disconnected queue.
2775 */
2776
2777 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp;
2778 tmp = NEXT(tmp))
2779 if (cmd == tmp) {
2780 local_irq_restore(flags);
2781 ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO);
2782
2783 if (NCR5380_select (instance, cmd, (int) cmd->tag))
2784 return SCSI_ABORT_BUSY;
2785
2786 ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO);
2787
2788 do_abort (instance);
2789
2790 local_irq_save(flags);
2791 for (prev = (Scsi_Cmnd **) &(hostdata->disconnected_queue),
2792 tmp = (Scsi_Cmnd *) hostdata->disconnected_queue;
2793 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) )
2794 if (cmd == tmp) {
2795 REMOVE(5, *prev, tmp, NEXT(tmp));
2796 *prev = NEXT(tmp);
2797 NEXT(tmp) = NULL;
2798 tmp->result = DID_ABORT << 16;
2799 /* We must unlock the tag/LUN immediately here, since the
2800 * target goes to BUS FREE and doesn't send us another
2801 * message (COMMAND_COMPLETE or the like)
2802 */
2803#ifdef SUPPORT_TAGS
2804 cmd_free_tag( tmp );
2805#else
2806 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2807#endif
2808 local_irq_restore(flags);
2809 tmp->scsi_done(tmp);
2810 falcon_release_lock_if_possible( hostdata );
2811 return SCSI_ABORT_SUCCESS;
2812 }
2813 }
2814
2815/*
2816 * Case 5 : If we reached this point, the command was not found in any of
2817 * the queues.
2818 *
2819 * We probably reached this point because of an unlikely race condition
2820 * between the command completing successfully and the abortion code,
2821 * so we won't panic, but we will notify the user in case something really
2822 * broke.
2823 */
2824
2825 local_irq_restore(flags);
2826 printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully\n"
2827 KERN_INFO " before abortion\n", HOSTNO);
2828
2829/* Maybe it is sufficient just to release the ST-DMA lock... (if
2830 * possible at all) At least, we should check if the lock could be
2831 * released after the abort, in case it is kept due to some bug.
2832 */
2833 falcon_release_lock_if_possible( hostdata );
2834
2835 return SCSI_ABORT_NOT_RUNNING;
2836}
2837
2838
2839/*
2840 * Function : int NCR5380_reset (Scsi_Cmnd *cmd)
2841 *
2842 * Purpose : reset the SCSI bus.
2843 *
2844 * Returns : SCSI_RESET_WAKEUP
2845 *
2846 */
2847
2848static int NCR5380_bus_reset( Scsi_Cmnd *cmd)
2849{
2850 SETUP_HOSTDATA(cmd->device->host);
2851 int i;
2852 unsigned long flags;
2853#if 1
2854 Scsi_Cmnd *connected, *disconnected_queue;
2855#endif
2856
2857 if (!IS_A_TT() && !falcon_got_lock)
2858 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n",
2859 H_NO(cmd) );
2860
2861 NCR5380_print_status (cmd->device->host);
2862
2863 /* get in phase */
2864 NCR5380_write( TARGET_COMMAND_REG,
2865 PHASE_SR_TO_TCR( NCR5380_read(STATUS_REG) ));
2866 /* assert RST */
2867 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST );
2868 udelay (40);
2869 /* reset NCR registers */
2870 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE );
2871 NCR5380_write( MODE_REG, MR_BASE );
2872 NCR5380_write( TARGET_COMMAND_REG, 0 );
2873 NCR5380_write( SELECT_ENABLE_REG, 0 );
2874 /* ++roman: reset interrupt condition! otherwise no interrupts don't get
2875 * through anymore ... */
2876 (void)NCR5380_read( RESET_PARITY_INTERRUPT_REG );
2877
2878#if 1 /* XXX Should now be done by midlevel code, but it's broken XXX */
2879 /* XXX see below XXX */
2880
2881 /* MSch: old-style reset: actually abort all command processing here */
2882
2883 /* After the reset, there are no more connected or disconnected commands
2884 * and no busy units; to avoid problems with re-inserting the commands
2885 * into the issue_queue (via scsi_done()), the aborted commands are
2886 * remembered in local variables first.
2887 */
2888 local_irq_save(flags);
2889 connected = (Scsi_Cmnd *)hostdata->connected;
2890 hostdata->connected = NULL;
2891 disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue;
2892 hostdata->disconnected_queue = NULL;
2893#ifdef SUPPORT_TAGS
2894 free_all_tags();
2895#endif
2896 for( i = 0; i < 8; ++i )
2897 hostdata->busy[i] = 0;
2898#ifdef REAL_DMA
2899 hostdata->dma_len = 0;
2900#endif
2901 local_irq_restore(flags);
2902
2903 /* In order to tell the mid-level code which commands were aborted,
2904 * set the command status to DID_RESET and call scsi_done() !!!
2905 * This ultimately aborts processing of these commands in the mid-level.
2906 */
2907
2908 if ((cmd = connected)) {
2909 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2910 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2911 cmd->scsi_done( cmd );
2912 }
2913
2914 for (i = 0; (cmd = disconnected_queue); ++i) {
2915 disconnected_queue = NEXT(cmd);
2916 NEXT(cmd) = NULL;
2917 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2918 cmd->scsi_done( cmd );
2919 }
2920 if (i > 0)
2921 ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i);
2922
2923/* The Falcon lock should be released after a reset...
2924 */
2925/* ++guenther: moved to atari_scsi_reset(), to prevent a race between
2926 * unlocking and enabling dma interrupt.
2927 */
2928/* falcon_release_lock_if_possible( hostdata );*/
2929
2930 /* since all commands have been explicitly terminated, we need to tell
2931 * the midlevel code that the reset was SUCCESSFUL, and there is no
2932 * need to 'wake up' the commands by a request_sense
2933 */
2934 return SCSI_RESET_SUCCESS | SCSI_RESET_BUS_RESET;
2935#else /* 1 */
2936
2937 /* MSch: new-style reset handling: let the mid-level do what it can */
2938
2939 /* ++guenther: MID-LEVEL IS STILL BROKEN.
2940 * Mid-level is supposed to requeue all commands that were active on the
2941 * various low-level queues. In fact it does this, but that's not enough
2942 * because all these commands are subject to timeout. And if a timeout
2943 * happens for any removed command, *_abort() is called but all queues
2944 * are now empty. Abort then gives up the falcon lock, which is fatal,
2945 * since the mid-level will queue more commands and must have the lock
2946 * (it's all happening inside timer interrupt handler!!).
2947 * Even worse, abort will return NOT_RUNNING for all those commands not
2948 * on any queue, so they won't be retried ...
2949 *
2950 * Conclusion: either scsi.c disables timeout for all resetted commands
2951 * immediately, or we lose! As of linux-2.0.20 it doesn't.
2952 */
2953
2954 /* After the reset, there are no more connected or disconnected commands
2955 * and no busy units; so clear the low-level status here to avoid
2956 * conflicts when the mid-level code tries to wake up the affected
2957 * commands!
2958 */
2959
2960 if (hostdata->issue_queue)
2961 ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2962 if (hostdata->connected)
2963 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2964 if (hostdata->disconnected_queue)
2965 ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
2966
2967 local_irq_save(flags);
2968 hostdata->issue_queue = NULL;
2969 hostdata->connected = NULL;
2970 hostdata->disconnected_queue = NULL;
2971#ifdef SUPPORT_TAGS
2972 free_all_tags();
2973#endif
2974 for( i = 0; i < 8; ++i )
2975 hostdata->busy[i] = 0;
2976#ifdef REAL_DMA
2977 hostdata->dma_len = 0;
2978#endif
2979 local_irq_restore(flags);
2980
2981 /* we did no complete reset of all commands, so a wakeup is required */
2982 return SCSI_RESET_WAKEUP | SCSI_RESET_BUS_RESET;
2983#endif /* 1 */
2984}
2985
2986/* Local Variables: */
2987/* tab-width: 8 */
2988/* End: */