blob: 2c12be72c4c6abe0e72048e0b092bd2c6379b9cb [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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
78#if (NDEBUG & NDEBUG_LISTS)
79#define LIST(x,y) \
80 { printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); \
81 if ((x)==(y)) udelay(5); }
82#define REMOVE(w,x,y,z) \
83 { printk("LINE:%d Removing: %p->%p %p->%p \n", __LINE__, \
84 (void*)(w), (void*)(x), (void*)(y), (void*)(z)); \
85 if ((x)==(y)) udelay(5); }
86#else
87#define LIST(x,y)
88#define REMOVE(w,x,y,z)
89#endif
90
91#ifndef notyet
92#undef LINKED
93#endif
94
95/*
96 * Design
97 * Issues :
98 *
99 * The other Linux SCSI drivers were written when Linux was Intel PC-only,
100 * and specifically for each board rather than each chip. This makes their
101 * adaptation to platforms like the Mac (Some of which use NCR5380's)
102 * more difficult than it has to be.
103 *
104 * Also, many of the SCSI drivers were written before the command queuing
105 * routines were implemented, meaning their implementations of queued
106 * commands were hacked on rather than designed in from the start.
107 *
108 * When I designed the Linux SCSI drivers I figured that
109 * while having two different SCSI boards in a system might be useful
110 * for debugging things, two of the same type wouldn't be used.
111 * Well, I was wrong and a number of users have mailed me about running
112 * multiple high-performance SCSI boards in a server.
113 *
114 * Finally, when I get questions from users, I have no idea what
115 * revision of my driver they are running.
116 *
117 * This driver attempts to address these problems :
118 * This is a generic 5380 driver. To use it on a different platform,
119 * one simply writes appropriate system specific macros (ie, data
120 * transfer - some PC's will use the I/O bus, 68K's must use
121 * memory mapped) and drops this file in their 'C' wrapper.
122 *
123 * As far as command queueing, two queues are maintained for
124 * each 5380 in the system - commands that haven't been issued yet,
125 * and commands that are currently executing. This means that an
126 * unlimited number of commands may be queued, letting
127 * more commands propagate from the higher driver levels giving higher
128 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
129 * allowing multiple commands to propagate all the way to a SCSI-II device
130 * while a command is already executing.
131 *
132 * To solve the multiple-boards-in-the-same-system problem,
133 * there is a separate instance structure for each instance
134 * of a 5380 in the system. So, multiple NCR5380 drivers will
135 * be able to coexist with appropriate changes to the high level
136 * SCSI code.
137 *
138 * A NCR5380_PUBLIC_REVISION macro is provided, with the release
139 * number (updated for each public release) printed by the
140 * NCR5380_print_options command, which should be called from the
141 * wrapper detect function, so that I know what release of the driver
142 * users are using.
143 *
144 * Issues specific to the NCR5380 :
145 *
146 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
147 * piece of hardware that requires you to sit in a loop polling for
148 * the REQ signal as long as you are connected. Some devices are
149 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
150 * while doing long seek operations.
151 *
152 * The workaround for this is to keep track of devices that have
153 * disconnected. If the device hasn't disconnected, for commands that
154 * should disconnect, we do something like
155 *
156 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
157 *
158 * Some tweaking of N and M needs to be done. An algorithm based
159 * on "time to data" would give the best results as long as short time
160 * to datas (ie, on the same track) were considered, however these
161 * broken devices are the exception rather than the rule and I'd rather
162 * spend my time optimizing for the normal case.
163 *
164 * Architecture :
165 *
166 * At the heart of the design is a coroutine, NCR5380_main,
167 * which is started when not running by the interrupt handler,
168 * timer, and queue command function. It attempts to establish
169 * I_T_L or I_T_L_Q nexuses by removing the commands from the
170 * issue queue and calling NCR5380_select() if a nexus
171 * is not established.
172 *
173 * Once a nexus is established, the NCR5380_information_transfer()
174 * phase goes through the various phases as instructed by the target.
175 * if the target goes into MSG IN and sends a DISCONNECT message,
176 * the command structure is placed into the per instance disconnected
177 * queue, and NCR5380_main tries to find more work. If USLEEP
178 * was defined, and the target is idle for too long, the system
179 * will try to sleep.
180 *
181 * If a command has disconnected, eventually an interrupt will trigger,
182 * calling NCR5380_intr() which will in turn call NCR5380_reselect
183 * to reestablish a nexus. This will run main if necessary.
184 *
185 * On command termination, the done function will be called as
186 * appropriate.
187 *
188 * SCSI pointers are maintained in the SCp field of SCSI command
189 * structures, being initialized after the command is connected
190 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
191 * Note that in violation of the standard, an implicit SAVE POINTERS operation
192 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
193 */
194
195/*
196 * Using this file :
197 * This file a skeleton Linux SCSI driver for the NCR 5380 series
198 * of chips. To use it, you write an architecture specific functions
199 * and macros and include this file in your driver.
200 *
201 * These macros control options :
202 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
203 * for commands that return with a CHECK CONDITION status.
204 *
205 * LINKED - if defined, linked commands are supported.
206 *
207 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
208 *
209 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
210 *
211 * These macros MUST be defined :
212 *
213 * NCR5380_read(register) - read from the specified register
214 *
215 * NCR5380_write(register, value) - write to the specific register
216 *
217 * Either real DMA *or* pseudo DMA may be implemented
218 * REAL functions :
219 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
220 * Note that the DMA setup functions should return the number of bytes
221 * that they were able to program the controller for.
222 *
223 * Also note that generic i386/PC versions of these macros are
224 * available as NCR5380_i386_dma_write_setup,
225 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
226 *
227 * NCR5380_dma_write_setup(instance, src, count) - initialize
228 * NCR5380_dma_read_setup(instance, dst, count) - initialize
229 * NCR5380_dma_residual(instance); - residual count
230 *
231 * PSEUDO functions :
232 * NCR5380_pwrite(instance, src, count)
233 * NCR5380_pread(instance, dst, count);
234 *
235 * If nothing specific to this implementation needs doing (ie, with external
236 * hardware), you must also define
237 *
238 * NCR5380_queue_command
239 * NCR5380_reset
240 * NCR5380_abort
241 * NCR5380_proc_info
242 *
243 * to be the global entry points into the specific driver, ie
244 * #define NCR5380_queue_command t128_queue_command.
245 *
246 * If this is not done, the routines will be defined as static functions
247 * with the NCR5380* names and the user must provide a globally
248 * accessible wrapper function.
249 *
250 * The generic driver is initialized by calling NCR5380_init(instance),
251 * after setting the appropriate host specific fields and ID. If the
252 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
253 * possible) function may be used. Before the specific driver initialization
254 * code finishes, NCR5380_print_options should be called.
255 */
256
257static struct Scsi_Host *first_instance = NULL;
258static Scsi_Host_Template *the_template = NULL;
259
260/* Macros ease life... :-) */
261#define SETUP_HOSTDATA(in) \
262 struct NCR5380_hostdata *hostdata = \
263 (struct NCR5380_hostdata *)(in)->hostdata
264#define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)
265
266#define NEXT(cmd) ((Scsi_Cmnd *)((cmd)->host_scribble))
267#define NEXTADDR(cmd) ((Scsi_Cmnd **)&((cmd)->host_scribble))
268
269#define HOSTNO instance->host_no
270#define H_NO(cmd) (cmd)->device->host->host_no
271
272#ifdef SUPPORT_TAGS
273
274/*
275 * Functions for handling tagged queuing
276 * =====================================
277 *
278 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
279 *
280 * Using consecutive numbers for the tags is no good idea in my eyes. There
281 * could be wrong re-usings if the counter (8 bit!) wraps and some early
282 * command has been preempted for a long time. My solution: a bitfield for
283 * remembering used tags.
284 *
285 * There's also the problem that each target has a certain queue size, but we
286 * cannot know it in advance :-( We just see a QUEUE_FULL status being
287 * returned. So, in this case, the driver internal queue size assumption is
288 * reduced to the number of active tags if QUEUE_FULL is returned by the
289 * target. The command is returned to the mid-level, but with status changed
290 * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL
291 * correctly.
292 *
293 * We're also not allowed running tagged commands as long as an untagged
294 * command is active. And REQUEST SENSE commands after a contingent allegiance
295 * condition _must_ be untagged. To keep track whether an untagged command has
296 * been issued, the host->busy array is still employed, as it is without
297 * support for tagged queuing.
298 *
299 * One could suspect that there are possible race conditions between
300 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
301 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
302 * which already guaranteed to be running at most once. It is also the only
303 * place where tags/LUNs are allocated. So no other allocation can slip
304 * between that pair, there could only happen a reselection, which can free a
305 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
306 * important: the tag bit must be cleared before 'nr_allocated' is decreased.
307 */
308
309/* -1 for TAG_NONE is not possible with unsigned char cmd->tag */
310#undef TAG_NONE
311#define TAG_NONE 0xff
312
313typedef struct {
314 DECLARE_BITMAP(allocated, MAX_TAGS);
315 int nr_allocated;
316 int queue_size;
317} TAG_ALLOC;
318
319static TAG_ALLOC TagAlloc[8][8]; /* 8 targets and 8 LUNs */
320
321
322static void __init init_tags( void )
323{
324 int target, lun;
325 TAG_ALLOC *ta;
326
327 if (!setup_use_tagged_queuing)
328 return;
329
330 for( target = 0; target < 8; ++target ) {
331 for( lun = 0; lun < 8; ++lun ) {
332 ta = &TagAlloc[target][lun];
333 bitmap_zero(ta->allocated, MAX_TAGS);
334 ta->nr_allocated = 0;
335 /* At the beginning, assume the maximum queue size we could
336 * support (MAX_TAGS). This value will be decreased if the target
337 * returns QUEUE_FULL status.
338 */
339 ta->queue_size = MAX_TAGS;
340 }
341 }
342}
343
344
345/* Check if we can issue a command to this LUN: First see if the LUN is marked
346 * busy by an untagged command. If the command should use tagged queuing, also
347 * check that there is a free tag and the target's queue won't overflow. This
348 * function should be called with interrupts disabled to avoid race
349 * conditions.
350 */
351
352static int is_lun_busy( Scsi_Cmnd *cmd, int should_be_tagged )
353{
354 SETUP_HOSTDATA(cmd->device->host);
355
356 if (hostdata->busy[cmd->device->id] & (1 << cmd->device->lun))
357 return( 1 );
358 if (!should_be_tagged ||
359 !setup_use_tagged_queuing || !cmd->device->tagged_supported)
360 return( 0 );
361 if (TagAlloc[cmd->device->id][cmd->device->lun].nr_allocated >=
362 TagAlloc[cmd->device->id][cmd->device->lun].queue_size ) {
363 TAG_PRINTK( "scsi%d: target %d lun %d: no free tags\n",
364 H_NO(cmd), cmd->device->id, cmd->device->lun );
365 return( 1 );
366 }
367 return( 0 );
368}
369
370
371/* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
372 * must be called before!), or reserve the LUN in 'busy' if the command is
373 * untagged.
374 */
375
376static void cmd_get_tag( Scsi_Cmnd *cmd, int should_be_tagged )
377{
378 SETUP_HOSTDATA(cmd->device->host);
379
380 /* If we or the target don't support tagged queuing, allocate the LUN for
381 * an untagged command.
382 */
383 if (!should_be_tagged ||
384 !setup_use_tagged_queuing || !cmd->device->tagged_supported) {
385 cmd->tag = TAG_NONE;
386 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
387 TAG_PRINTK( "scsi%d: target %d lun %d now allocated by untagged "
388 "command\n", H_NO(cmd), cmd->device->id, cmd->device->lun );
389 }
390 else {
391 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
392
393 cmd->tag = find_first_zero_bit( ta->allocated, MAX_TAGS );
394 set_bit( cmd->tag, ta->allocated );
395 ta->nr_allocated++;
396 TAG_PRINTK( "scsi%d: using tag %d for target %d lun %d "
397 "(now %d tags in use)\n",
398 H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun,
399 ta->nr_allocated );
400 }
401}
402
403
404/* Mark the tag of command 'cmd' as free, or in case of an untagged command,
405 * unlock the LUN.
406 */
407
408static void cmd_free_tag( Scsi_Cmnd *cmd )
409{
410 SETUP_HOSTDATA(cmd->device->host);
411
412 if (cmd->tag == TAG_NONE) {
413 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
414 TAG_PRINTK( "scsi%d: target %d lun %d untagged cmd finished\n",
415 H_NO(cmd), cmd->device->id, cmd->device->lun );
416 }
417 else if (cmd->tag >= MAX_TAGS) {
418 printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n",
419 H_NO(cmd), cmd->tag );
420 }
421 else {
422 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
423 clear_bit( cmd->tag, ta->allocated );
424 ta->nr_allocated--;
425 TAG_PRINTK( "scsi%d: freed tag %d for target %d lun %d\n",
426 H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun );
427 }
428}
429
430
431static void free_all_tags( void )
432{
433 int target, lun;
434 TAG_ALLOC *ta;
435
436 if (!setup_use_tagged_queuing)
437 return;
438
439 for( target = 0; target < 8; ++target ) {
440 for( lun = 0; lun < 8; ++lun ) {
441 ta = &TagAlloc[target][lun];
442 bitmap_zero(ta->allocated, MAX_TAGS);
443 ta->nr_allocated = 0;
444 }
445 }
446}
447
448#endif /* SUPPORT_TAGS */
449
450
451/*
452 * Function: void merge_contiguous_buffers( Scsi_Cmnd *cmd )
453 *
454 * Purpose: Try to merge several scatter-gather requests into one DMA
455 * transfer. This is possible if the scatter buffers lie on
456 * physical contiguous addresses.
457 *
458 * Parameters: Scsi_Cmnd *cmd
459 * The command to work on. The first scatter buffer's data are
460 * assumed to be already transfered into ptr/this_residual.
461 */
462
463static void merge_contiguous_buffers( Scsi_Cmnd *cmd )
464{
465 unsigned long endaddr;
466#if (NDEBUG & NDEBUG_MERGING)
467 unsigned long oldlen = cmd->SCp.this_residual;
468 int cnt = 1;
469#endif
470
471 for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
472 cmd->SCp.buffers_residual &&
473 virt_to_phys(page_address(cmd->SCp.buffer[1].page)+
474 cmd->SCp.buffer[1].offset) == endaddr; ) {
475 MER_PRINTK("VTOP(%p) == %08lx -> merging\n",
476 cmd->SCp.buffer[1].address, endaddr);
477#if (NDEBUG & NDEBUG_MERGING)
478 ++cnt;
479#endif
480 ++cmd->SCp.buffer;
481 --cmd->SCp.buffers_residual;
482 cmd->SCp.this_residual += cmd->SCp.buffer->length;
483 endaddr += cmd->SCp.buffer->length;
484 }
485#if (NDEBUG & NDEBUG_MERGING)
486 if (oldlen != cmd->SCp.this_residual)
487 MER_PRINTK("merged %d buffers from %p, new length %08x\n",
488 cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
489#endif
490}
491
492/*
493 * Function : void initialize_SCp(Scsi_Cmnd *cmd)
494 *
495 * Purpose : initialize the saved data pointers for cmd to point to the
496 * start of the buffer.
497 *
498 * Inputs : cmd - Scsi_Cmnd structure to have pointers reset.
499 */
500
501static __inline__ void initialize_SCp(Scsi_Cmnd *cmd)
502{
503 /*
504 * Initialize the Scsi Pointer field so that all of the commands in the
505 * various queues are valid.
506 */
507
508 if (cmd->use_sg) {
509 cmd->SCp.buffer = (struct scatterlist *) cmd->buffer;
510 cmd->SCp.buffers_residual = cmd->use_sg - 1;
511 cmd->SCp.ptr = (char *)page_address(cmd->SCp.buffer->page)+
512 cmd->SCp.buffer->offset;
513 cmd->SCp.this_residual = cmd->SCp.buffer->length;
514 /* ++roman: Try to merge some scatter-buffers if they are at
515 * contiguous physical addresses.
516 */
517 merge_contiguous_buffers( cmd );
518 } else {
519 cmd->SCp.buffer = NULL;
520 cmd->SCp.buffers_residual = 0;
521 cmd->SCp.ptr = (char *) cmd->request_buffer;
522 cmd->SCp.this_residual = cmd->request_bufflen;
523 }
524}
525
526#include <linux/config.h>
527#include <linux/delay.h>
528
529#if NDEBUG
530static struct {
531 unsigned char mask;
532 const char * name;}
533signals[] = {{ SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" },
534 { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" },
535 { SR_SEL, "SEL" }, {0, NULL}},
536basrs[] = {{BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}},
537icrs[] = {{ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"},
538 {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"},
539 {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"},
540 {0, NULL}},
541mrs[] = {{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"},
542 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR,
543 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"},
544 {MR_MONITOR_BSY, "MODE MONITOR BSY"},
545 {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"},
546 {0, NULL}};
547
548/*
549 * Function : void NCR5380_print(struct Scsi_Host *instance)
550 *
551 * Purpose : print the SCSI bus signals for debugging purposes
552 *
553 * Input : instance - which NCR5380
554 */
555
556static void NCR5380_print(struct Scsi_Host *instance) {
557 unsigned char status, data, basr, mr, icr, i;
558 unsigned long flags;
559
560 local_irq_save(flags);
561 data = NCR5380_read(CURRENT_SCSI_DATA_REG);
562 status = NCR5380_read(STATUS_REG);
563 mr = NCR5380_read(MODE_REG);
564 icr = NCR5380_read(INITIATOR_COMMAND_REG);
565 basr = NCR5380_read(BUS_AND_STATUS_REG);
566 local_irq_restore(flags);
567 printk("STATUS_REG: %02x ", status);
568 for (i = 0; signals[i].mask ; ++i)
569 if (status & signals[i].mask)
570 printk(",%s", signals[i].name);
571 printk("\nBASR: %02x ", basr);
572 for (i = 0; basrs[i].mask ; ++i)
573 if (basr & basrs[i].mask)
574 printk(",%s", basrs[i].name);
575 printk("\nICR: %02x ", icr);
576 for (i = 0; icrs[i].mask; ++i)
577 if (icr & icrs[i].mask)
578 printk(",%s", icrs[i].name);
579 printk("\nMODE: %02x ", mr);
580 for (i = 0; mrs[i].mask; ++i)
581 if (mr & mrs[i].mask)
582 printk(",%s", mrs[i].name);
583 printk("\n");
584}
585
586static struct {
587 unsigned char value;
588 const char *name;
589} phases[] = {
590 {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
591 {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
592 {PHASE_UNKNOWN, "UNKNOWN"}};
593
594/*
595 * Function : void NCR5380_print_phase(struct Scsi_Host *instance)
596 *
597 * Purpose : print the current SCSI phase for debugging purposes
598 *
599 * Input : instance - which NCR5380
600 */
601
602static void NCR5380_print_phase(struct Scsi_Host *instance)
603{
604 unsigned char status;
605 int i;
606
607 status = NCR5380_read(STATUS_REG);
608 if (!(status & SR_REQ))
609 printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO);
610 else {
611 for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
612 (phases[i].value != (status & PHASE_MASK)); ++i);
613 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name);
614 }
615}
616
617#else /* !NDEBUG */
618
619/* dummies... */
620__inline__ void NCR5380_print(struct Scsi_Host *instance) { };
621__inline__ void NCR5380_print_phase(struct Scsi_Host *instance) { };
622
623#endif
624
625/*
626 * ++roman: New scheme of calling NCR5380_main()
627 *
628 * If we're not in an interrupt, we can call our main directly, it cannot be
629 * already running. Else, we queue it on a task queue, if not 'main_running'
630 * tells us that a lower level is already executing it. This way,
631 * 'main_running' needs not be protected in a special way.
632 *
633 * queue_main() is a utility function for putting our main onto the task
634 * queue, if main_running is false. It should be called only from a
635 * interrupt or bottom half.
636 */
637
638#include <linux/workqueue.h>
639#include <linux/interrupt.h>
640
641static volatile int main_running = 0;
642static DECLARE_WORK(NCR5380_tqueue, (void (*)(void*))NCR5380_main, NULL);
643
644static __inline__ void queue_main(void)
645{
646 if (!main_running) {
647 /* If in interrupt and NCR5380_main() not already running,
648 queue it on the 'immediate' task queue, to be processed
649 immediately after the current interrupt processing has
650 finished. */
651 schedule_work(&NCR5380_tqueue);
652 }
653 /* else: nothing to do: the running NCR5380_main() will pick up
654 any newly queued command. */
655}
656
657
658static inline void NCR5380_all_init (void)
659{
660 static int done = 0;
661 if (!done) {
662 INI_PRINTK("scsi : NCR5380_all_init()\n");
663 done = 1;
664 }
665}
666
667
668/*
669 * Function : void NCR58380_print_options (struct Scsi_Host *instance)
670 *
671 * Purpose : called by probe code indicating the NCR5380 driver
672 * options that were selected.
673 *
674 * Inputs : instance, pointer to this instance. Unused.
675 */
676
677static void __init NCR5380_print_options (struct Scsi_Host *instance)
678{
679 printk(" generic options"
680#ifdef AUTOSENSE
681 " AUTOSENSE"
682#endif
683#ifdef REAL_DMA
684 " REAL DMA"
685#endif
686#ifdef PARITY
687 " PARITY"
688#endif
689#ifdef SUPPORT_TAGS
690 " SCSI-2 TAGGED QUEUING"
691#endif
692 );
693 printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
694}
695
696/*
697 * Function : void NCR5380_print_status (struct Scsi_Host *instance)
698 *
699 * Purpose : print commands in the various queues, called from
700 * NCR5380_abort and NCR5380_debug to aid debugging.
701 *
702 * Inputs : instance, pointer to this instance.
703 */
704
705static void NCR5380_print_status (struct Scsi_Host *instance)
706{
707 char *pr_bfr;
708 char *start;
709 int len;
710
711 NCR_PRINT(NDEBUG_ANY);
712 NCR_PRINT_PHASE(NDEBUG_ANY);
713
714 pr_bfr = (char *) __get_free_page(GFP_ATOMIC);
715 if (!pr_bfr) {
716 printk("NCR5380_print_status: no memory for print buffer\n");
717 return;
718 }
719 len = NCR5380_proc_info(pr_bfr, &start, 0, PAGE_SIZE, HOSTNO, 0);
720 pr_bfr[len] = 0;
721 printk("\n%s\n", pr_bfr);
722 free_page((unsigned long) pr_bfr);
723}
724
725
726/******************************************/
727/*
728 * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
729 *
730 * *buffer: I/O buffer
731 * **start: if inout == FALSE pointer into buffer where user read should start
732 * offset: current offset
733 * length: length of buffer
734 * hostno: Scsi_Host host_no
735 * inout: TRUE - user is writing; FALSE - user is reading
736 *
737 * Return the number of bytes read from or written
738*/
739
740#undef SPRINTF
741#define SPRINTF(fmt,args...) \
742 do { if (pos + strlen(fmt) + 20 /* slop */ < buffer + length) \
743 pos += sprintf(pos, fmt , ## args); } while(0)
744static
745char *lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length);
746
747static
748int NCR5380_proc_info (struct Scsi_Host *instance, char *buffer, char **start, off_t offset,
749 int length, int inout)
750{
751 char *pos = buffer;
752 struct NCR5380_hostdata *hostdata;
753 Scsi_Cmnd *ptr;
754 unsigned long flags;
755 off_t begin = 0;
756#define check_offset() \
757 do { \
758 if (pos - buffer < offset - begin) { \
759 begin += pos - buffer; \
760 pos = buffer; \
761 } \
762 } while (0)
763
764 hostdata = (struct NCR5380_hostdata *)instance->hostdata;
765
766 if (inout) { /* Has data been written to the file ? */
767 return(-ENOSYS); /* Currently this is a no-op */
768 }
769 SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
770 check_offset();
771 local_irq_save(flags);
772 SPRINTF("NCR5380: coroutine is%s running.\n", main_running ? "" : "n't");
773 check_offset();
774 if (!hostdata->connected)
775 SPRINTF("scsi%d: no currently connected command\n", HOSTNO);
776 else
777 pos = lprint_Scsi_Cmnd ((Scsi_Cmnd *) hostdata->connected,
778 pos, buffer, length);
779 SPRINTF("scsi%d: issue_queue\n", HOSTNO);
780 check_offset();
781 for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = NEXT(ptr)) {
782 pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
783 check_offset();
784 }
785
786 SPRINTF("scsi%d: disconnected_queue\n", HOSTNO);
787 check_offset();
788 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr;
789 ptr = NEXT(ptr)) {
790 pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
791 check_offset();
792 }
793
794 local_irq_restore(flags);
795 *start = buffer + (offset - begin);
796 if (pos - buffer < offset - begin)
797 return 0;
798 else if (pos - buffer - (offset - begin) < length)
799 return pos - buffer - (offset - begin);
800 return length;
801}
802
803static char *
804lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length)
805{
806 int i, s;
807 unsigned char *command;
808 SPRINTF("scsi%d: destination target %d, lun %d\n",
809 H_NO(cmd), cmd->device->id, cmd->device->lun);
810 SPRINTF(" command = ");
811 command = cmd->cmnd;
812 SPRINTF("%2d (0x%02x)", command[0], command[0]);
813 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
814 SPRINTF(" %02x", command[i]);
815 SPRINTF("\n");
816 return pos;
817}
818
819
820/*
821 * Function : void NCR5380_init (struct Scsi_Host *instance)
822 *
823 * Purpose : initializes *instance and corresponding 5380 chip.
824 *
825 * Inputs : instance - instantiation of the 5380 driver.
826 *
827 * Notes : I assume that the host, hostno, and id bits have been
828 * set correctly. I don't care about the irq and other fields.
829 *
830 */
831
832static int NCR5380_init (struct Scsi_Host *instance, int flags)
833{
834 int i;
835 SETUP_HOSTDATA(instance);
836
837 NCR5380_all_init();
838
839 hostdata->aborted = 0;
840 hostdata->id_mask = 1 << instance->this_id;
841 hostdata->id_higher_mask = 0;
842 for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
843 if (i > hostdata->id_mask)
844 hostdata->id_higher_mask |= i;
845 for (i = 0; i < 8; ++i)
846 hostdata->busy[i] = 0;
847#ifdef SUPPORT_TAGS
848 init_tags();
849#endif
850#if defined (REAL_DMA)
851 hostdata->dma_len = 0;
852#endif
853 hostdata->targets_present = 0;
854 hostdata->connected = NULL;
855 hostdata->issue_queue = NULL;
856 hostdata->disconnected_queue = NULL;
857 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT;
858
859 if (!the_template) {
860 the_template = instance->hostt;
861 first_instance = instance;
862 }
863
864
865#ifndef AUTOSENSE
866 if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1))
867 printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n"
868 " without AUTOSENSE option, contingent allegiance conditions may\n"
869 " be incorrectly cleared.\n", HOSTNO);
870#endif /* def AUTOSENSE */
871
872 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
873 NCR5380_write(MODE_REG, MR_BASE);
874 NCR5380_write(TARGET_COMMAND_REG, 0);
875 NCR5380_write(SELECT_ENABLE_REG, 0);
876
877 return 0;
878}
879
880/*
881 * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd,
882 * void (*done)(Scsi_Cmnd *))
883 *
884 * Purpose : enqueues a SCSI command
885 *
886 * Inputs : cmd - SCSI command, done - function called on completion, with
887 * a pointer to the command descriptor.
888 *
889 * Returns : 0
890 *
891 * Side effects :
892 * cmd is added to the per instance issue_queue, with minor
893 * twiddling done to the host specific fields of cmd. If the
894 * main coroutine is not running, it is restarted.
895 *
896 */
897
898static
899int NCR5380_queue_command (Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
900{
901 SETUP_HOSTDATA(cmd->device->host);
902 Scsi_Cmnd *tmp;
903 int oldto;
904 unsigned long flags;
905 extern int update_timeout(Scsi_Cmnd * SCset, int timeout);
906
907#if (NDEBUG & NDEBUG_NO_WRITE)
908 switch (cmd->cmnd[0]) {
909 case WRITE_6:
910 case WRITE_10:
911 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
912 H_NO(cmd));
913 cmd->result = (DID_ERROR << 16);
914 done(cmd);
915 return 0;
916 }
917#endif /* (NDEBUG & NDEBUG_NO_WRITE) */
918
919
920#ifdef NCR5380_STATS
921# if 0
922 if (!hostdata->connected && !hostdata->issue_queue &&
923 !hostdata->disconnected_queue) {
924 hostdata->timebase = jiffies;
925 }
926# endif
927# ifdef NCR5380_STAT_LIMIT
928 if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
929# endif
930 switch (cmd->cmnd[0])
931 {
932 case WRITE:
933 case WRITE_6:
934 case WRITE_10:
935 hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
936 hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen;
937 hostdata->pendingw++;
938 break;
939 case READ:
940 case READ_6:
941 case READ_10:
942 hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
943 hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen;
944 hostdata->pendingr++;
945 break;
946 }
947#endif
948
949 /*
950 * We use the host_scribble field as a pointer to the next command
951 * in a queue
952 */
953
954 NEXT(cmd) = NULL;
955 cmd->scsi_done = done;
956
957 cmd->result = 0;
958
959
960 /*
961 * Insert the cmd into the issue queue. Note that REQUEST SENSE
962 * commands are added to the head of the queue since any command will
963 * clear the contingent allegiance condition that exists and the
964 * sense data is only guaranteed to be valid while the condition exists.
965 */
966
967 local_irq_save(flags);
968 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
969 * Otherwise a running NCR5380_main may steal the lock.
970 * Lock before actually inserting due to fairness reasons explained in
971 * atari_scsi.c. If we insert first, then it's impossible for this driver
972 * to release the lock.
973 * Stop timer for this command while waiting for the lock, or timeouts
974 * may happen (and they really do), and it's no good if the command doesn't
975 * appear in any of the queues.
976 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
977 * because also a timer int can trigger an abort or reset, which would
978 * alter queues and touch the lock.
979 */
980 if (!IS_A_TT()) {
981 oldto = update_timeout(cmd, 0);
982 falcon_get_lock();
983 update_timeout(cmd, oldto);
984 }
985 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
986 LIST(cmd, hostdata->issue_queue);
987 NEXT(cmd) = hostdata->issue_queue;
988 hostdata->issue_queue = cmd;
989 } else {
990 for (tmp = (Scsi_Cmnd *)hostdata->issue_queue;
991 NEXT(tmp); tmp = NEXT(tmp))
992 ;
993 LIST(cmd, tmp);
994 NEXT(tmp) = cmd;
995 }
996 local_irq_restore(flags);
997
998 QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd),
999 (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
1000
1001 /* If queue_command() is called from an interrupt (real one or bottom
1002 * half), we let queue_main() do the job of taking care about main. If it
1003 * is already running, this is a no-op, else main will be queued.
1004 *
1005 * If we're not in an interrupt, we can call NCR5380_main()
1006 * unconditionally, because it cannot be already running.
1007 */
1008 if (in_interrupt() || ((flags >> 8) & 7) >= 6)
1009 queue_main();
1010 else
1011 NCR5380_main(NULL);
1012 return 0;
1013}
1014
1015/*
1016 * Function : NCR5380_main (void)
1017 *
1018 * Purpose : NCR5380_main is a coroutine that runs as long as more work can
1019 * be done on the NCR5380 host adapters in a system. Both
1020 * NCR5380_queue_command() and NCR5380_intr() will try to start it
1021 * in case it is not running.
1022 *
1023 * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
1024 * reenable them. This prevents reentrancy and kernel stack overflow.
1025 */
1026
1027static void NCR5380_main (void *bl)
1028{
1029 Scsi_Cmnd *tmp, *prev;
1030 struct Scsi_Host *instance = first_instance;
1031 struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
1032 int done;
1033 unsigned long flags;
1034
1035 /*
1036 * We run (with interrupts disabled) until we're sure that none of
1037 * the host adapters have anything that can be done, at which point
1038 * we set main_running to 0 and exit.
1039 *
1040 * Interrupts are enabled before doing various other internal
1041 * instructions, after we've decided that we need to run through
1042 * the loop again.
1043 *
1044 * this should prevent any race conditions.
1045 *
1046 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1047 * because also a timer int can trigger an abort or reset, which can
1048 * alter queues and touch the Falcon lock.
1049 */
1050
1051 /* Tell int handlers main() is now already executing. Note that
1052 no races are possible here. If an int comes in before
1053 'main_running' is set here, and queues/executes main via the
1054 task queue, it doesn't do any harm, just this instance of main
1055 won't find any work left to do. */
1056 if (main_running)
1057 return;
1058 main_running = 1;
1059
1060 local_save_flags(flags);
1061 do {
1062 local_irq_disable(); /* Freeze request queues */
1063 done = 1;
1064
1065 if (!hostdata->connected) {
1066 MAIN_PRINTK( "scsi%d: not connected\n", HOSTNO );
1067 /*
1068 * Search through the issue_queue for a command destined
1069 * for a target that's not busy.
1070 */
1071#if (NDEBUG & NDEBUG_LISTS)
1072 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL;
1073 tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
1074 ;
1075 /*printk("%p ", tmp);*/
1076 if ((tmp == prev) && tmp) printk(" LOOP\n");/* else printk("\n");*/
1077#endif
1078 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue,
1079 prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp) ) {
1080
1081#if (NDEBUG & NDEBUG_LISTS)
1082 if (prev != tmp)
1083 printk("MAIN tmp=%p target=%d busy=%d lun=%d\n",
1084 tmp, tmp->device->id, hostdata->busy[tmp->device->id],
1085 tmp->device->lun);
1086#endif
1087 /* When we find one, remove it from the issue queue. */
1088 /* ++guenther: possible race with Falcon locking */
1089 if (
1090#ifdef SUPPORT_TAGS
1091 !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
1092#else
1093 !(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))
1094#endif
1095 ) {
1096 /* ++guenther: just to be sure, this must be atomic */
1097 local_irq_disable();
1098 if (prev) {
1099 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1100 NEXT(prev) = NEXT(tmp);
1101 } else {
1102 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
1103 hostdata->issue_queue = NEXT(tmp);
1104 }
1105 NEXT(tmp) = NULL;
1106 falcon_dont_release++;
1107
1108 /* reenable interrupts after finding one */
1109 local_irq_restore(flags);
1110
1111 /*
1112 * Attempt to establish an I_T_L nexus here.
1113 * On success, instance->hostdata->connected is set.
1114 * On failure, we must add the command back to the
1115 * issue queue so we can keep trying.
1116 */
1117 MAIN_PRINTK("scsi%d: main(): command for target %d "
1118 "lun %d removed from issue_queue\n",
1119 HOSTNO, tmp->device->id, tmp->device->lun);
1120 /*
1121 * REQUEST SENSE commands are issued without tagged
1122 * queueing, even on SCSI-II devices because the
1123 * contingent allegiance condition exists for the
1124 * entire unit.
1125 */
1126 /* ++roman: ...and the standard also requires that
1127 * REQUEST SENSE command are untagged.
1128 */
1129
1130#ifdef SUPPORT_TAGS
1131 cmd_get_tag( tmp, tmp->cmnd[0] != REQUEST_SENSE );
1132#endif
1133 if (!NCR5380_select(instance, tmp,
1134 (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE :
1135 TAG_NEXT)) {
1136 falcon_dont_release--;
1137 /* release if target did not response! */
1138 falcon_release_lock_if_possible( hostdata );
1139 break;
1140 } else {
1141 local_irq_disable();
1142 LIST(tmp, hostdata->issue_queue);
1143 NEXT(tmp) = hostdata->issue_queue;
1144 hostdata->issue_queue = tmp;
1145#ifdef SUPPORT_TAGS
1146 cmd_free_tag( tmp );
1147#endif
1148 falcon_dont_release--;
1149 local_irq_restore(flags);
1150 MAIN_PRINTK("scsi%d: main(): select() failed, "
1151 "returned to issue_queue\n", HOSTNO);
1152 if (hostdata->connected)
1153 break;
1154 }
1155 } /* if target/lun/target queue is not busy */
1156 } /* for issue_queue */
1157 } /* if (!hostdata->connected) */
1158
1159 if (hostdata->connected
1160#ifdef REAL_DMA
1161 && !hostdata->dma_len
1162#endif
1163 ) {
1164 local_irq_restore(flags);
1165 MAIN_PRINTK("scsi%d: main: performing information transfer\n",
1166 HOSTNO);
1167 NCR5380_information_transfer(instance);
1168 MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO);
1169 done = 0;
1170 }
1171 } while (!done);
1172
1173 /* Better allow ints _after_ 'main_running' has been cleared, else
1174 an interrupt could believe we'll pick up the work it left for
1175 us, but we won't see it anymore here... */
1176 main_running = 0;
1177 local_irq_restore(flags);
1178}
1179
1180
1181#ifdef REAL_DMA
1182/*
1183 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1184 *
1185 * Purpose : Called by interrupt handler when DMA finishes or a phase
1186 * mismatch occurs (which would finish the DMA transfer).
1187 *
1188 * Inputs : instance - this instance of the NCR5380.
1189 *
1190 */
1191
1192static void NCR5380_dma_complete( struct Scsi_Host *instance )
1193{
1194 SETUP_HOSTDATA(instance);
1195 int transfered, saved_data = 0, overrun = 0, cnt, toPIO;
1196 unsigned char **data, p;
1197 volatile int *count;
1198
1199 if (!hostdata->connected) {
1200 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
1201 "no connected cmd\n", HOSTNO);
1202 return;
1203 }
1204
1205 if (atari_read_overruns) {
1206 p = hostdata->connected->SCp.phase;
1207 if (p & SR_IO) {
1208 udelay(10);
1209 if ((((NCR5380_read(BUS_AND_STATUS_REG)) &
1210 (BASR_PHASE_MATCH|BASR_ACK)) ==
1211 (BASR_PHASE_MATCH|BASR_ACK))) {
1212 saved_data = NCR5380_read(INPUT_DATA_REG);
1213 overrun = 1;
1214 DMA_PRINTK("scsi%d: read overrun handled\n", HOSTNO);
1215 }
1216 }
1217 }
1218
1219 DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1220 HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
1221 NCR5380_read(STATUS_REG));
1222
1223 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1224 NCR5380_write(MODE_REG, MR_BASE);
1225 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1226
1227 transfered = hostdata->dma_len - NCR5380_dma_residual(instance);
1228 hostdata->dma_len = 0;
1229
1230 data = (unsigned char **) &(hostdata->connected->SCp.ptr);
1231 count = &(hostdata->connected->SCp.this_residual);
1232 *data += transfered;
1233 *count -= transfered;
1234
1235 if (atari_read_overruns) {
1236 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
1237 cnt = toPIO = atari_read_overruns;
1238 if (overrun) {
1239 DMA_PRINTK("Got an input overrun, using saved byte\n");
1240 *(*data)++ = saved_data;
1241 (*count)--;
1242 cnt--;
1243 toPIO--;
1244 }
1245 DMA_PRINTK("Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
1246 NCR5380_transfer_pio(instance, &p, &cnt, data);
1247 *count -= toPIO - cnt;
1248 }
1249 }
1250}
1251#endif /* REAL_DMA */
1252
1253
1254/*
1255 * Function : void NCR5380_intr (int irq)
1256 *
1257 * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1258 * from the disconnected queue, and restarting NCR5380_main()
1259 * as required.
1260 *
1261 * Inputs : int irq, irq that caused this interrupt.
1262 *
1263 */
1264
1265static irqreturn_t NCR5380_intr (int irq, void *dev_id, struct pt_regs *regs)
1266{
1267 struct Scsi_Host *instance = first_instance;
1268 int done = 1, handled = 0;
1269 unsigned char basr;
1270
1271 INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO);
1272
1273 /* Look for pending interrupts */
1274 basr = NCR5380_read(BUS_AND_STATUS_REG);
1275 INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr);
1276 /* dispatch to appropriate routine if found and done=0 */
1277 if (basr & BASR_IRQ) {
1278 NCR_PRINT(NDEBUG_INTR);
1279 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
1280 done = 0;
1281 ENABLE_IRQ();
1282 INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO);
1283 NCR5380_reselect(instance);
1284 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1285 }
1286 else if (basr & BASR_PARITY_ERROR) {
1287 INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO);
1288 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1289 }
1290 else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1291 INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO);
1292 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1293 }
1294 else {
1295 /*
1296 * The rest of the interrupt conditions can occur only during a
1297 * DMA transfer
1298 */
1299
1300#if defined(REAL_DMA)
1301 /*
1302 * We should only get PHASE MISMATCH and EOP interrupts if we have
1303 * DMA enabled, so do a sanity check based on the current setting
1304 * of the MODE register.
1305 */
1306
1307 if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
1308 ((basr & BASR_END_DMA_TRANSFER) ||
1309 !(basr & BASR_PHASE_MATCH))) {
1310
1311 INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1312 NCR5380_dma_complete( instance );
1313 done = 0;
1314 ENABLE_IRQ();
1315 } else
1316#endif /* REAL_DMA */
1317 {
1318/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1319 if (basr & BASR_PHASE_MATCH)
1320 printk(KERN_NOTICE "scsi%d: unknown interrupt, "
1321 "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1322 HOSTNO, basr, NCR5380_read(MODE_REG),
1323 NCR5380_read(STATUS_REG));
1324 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1325 }
1326 } /* if !(SELECTION || PARITY) */
1327 handled = 1;
1328 } /* BASR & IRQ */
1329 else {
1330 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
1331 "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
1332 NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG));
1333 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1334 }
1335
1336 if (!done) {
1337 INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO);
1338 /* Put a call to NCR5380_main() on the queue... */
1339 queue_main();
1340 }
1341 return IRQ_RETVAL(handled);
1342}
1343
1344#ifdef NCR5380_STATS
1345static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd* cmd)
1346{
1347# ifdef NCR5380_STAT_LIMIT
1348 if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
1349# endif
1350 switch (cmd->cmnd[0])
1351 {
1352 case WRITE:
1353 case WRITE_6:
1354 case WRITE_10:
1355 hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase);
1356 /*hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen;*/
1357 hostdata->pendingw--;
1358 break;
1359 case READ:
1360 case READ_6:
1361 case READ_10:
1362 hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase);
1363 /*hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen;*/
1364 hostdata->pendingr--;
1365 break;
1366 }
1367}
1368#endif
1369
1370/*
1371 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1372 * int tag);
1373 *
1374 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1375 * including ARBITRATION, SELECTION, and initial message out for
1376 * IDENTIFY and queue messages.
1377 *
1378 * Inputs : instance - instantiation of the 5380 driver on which this
1379 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1380 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1381 * the command that is presently connected.
1382 *
1383 * Returns : -1 if selection could not execute for some reason,
1384 * 0 if selection succeeded or failed because the target
1385 * did not respond.
1386 *
1387 * Side effects :
1388 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1389 * with registers as they should have been on entry - ie
1390 * SELECT_ENABLE will be set appropriately, the NCR5380
1391 * will cease to drive any SCSI bus signals.
1392 *
1393 * If successful : I_T_L or I_T_L_Q nexus will be established,
1394 * instance->connected will be set to cmd.
1395 * SELECT interrupt will be disabled.
1396 *
1397 * If failed (no target) : cmd->scsi_done() will be called, and the
1398 * cmd->result host byte set to DID_BAD_TARGET.
1399 */
1400
1401static int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag)
1402{
1403 SETUP_HOSTDATA(instance);
1404 unsigned char tmp[3], phase;
1405 unsigned char *data;
1406 int len;
1407 unsigned long timeout;
1408 unsigned long flags;
1409
1410 hostdata->restart_select = 0;
1411 NCR_PRINT(NDEBUG_ARBITRATION);
1412 ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO,
1413 instance->this_id);
1414
1415 /*
1416 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1417 * data bus during SELECTION.
1418 */
1419
1420 local_irq_save(flags);
1421 if (hostdata->connected) {
1422 local_irq_restore(flags);
1423 return -1;
1424 }
1425 NCR5380_write(TARGET_COMMAND_REG, 0);
1426
1427
1428 /*
1429 * Start arbitration.
1430 */
1431
1432 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1433 NCR5380_write(MODE_REG, MR_ARBITRATE);
1434
1435 local_irq_restore(flags);
1436
1437 /* Wait for arbitration logic to complete */
1438#if NCR_TIMEOUT
1439 {
1440 unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
1441
1442 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)
1443 && time_before(jiffies, timeout) && !hostdata->connected)
1444 ;
1445 if (time_after_eq(jiffies, timeout))
1446 {
1447 printk("scsi : arbitration timeout at %d\n", __LINE__);
1448 NCR5380_write(MODE_REG, MR_BASE);
1449 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1450 return -1;
1451 }
1452 }
1453#else /* NCR_TIMEOUT */
1454 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)
1455 && !hostdata->connected);
1456#endif
1457
1458 ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO);
1459
1460 if (hostdata->connected) {
1461 NCR5380_write(MODE_REG, MR_BASE);
1462 return -1;
1463 }
1464 /*
1465 * The arbitration delay is 2.2us, but this is a minimum and there is
1466 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1467 * the integral nature of udelay().
1468 *
1469 */
1470
1471 udelay(3);
1472
1473 /* Check for lost arbitration */
1474 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1475 (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
1476 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1477 hostdata->connected) {
1478 NCR5380_write(MODE_REG, MR_BASE);
1479 ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1480 HOSTNO);
1481 return -1;
1482 }
1483
1484 /* after/during arbitration, BSY should be asserted.
1485 IBM DPES-31080 Version S31Q works now */
1486 /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
1487 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL |
1488 ICR_ASSERT_BSY ) ;
1489
1490 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1491 hostdata->connected) {
1492 NCR5380_write(MODE_REG, MR_BASE);
1493 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1494 ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1495 HOSTNO);
1496 return -1;
1497 }
1498
1499 /*
1500 * Again, bus clear + bus settle time is 1.2us, however, this is
1501 * a minimum so we'll udelay ceil(1.2)
1502 */
1503
1504#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1505 /* ++roman: But some targets (see above :-) seem to need a bit more... */
1506 udelay(15);
1507#else
1508 udelay(2);
1509#endif
1510
1511 if (hostdata->connected) {
1512 NCR5380_write(MODE_REG, MR_BASE);
1513 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1514 return -1;
1515 }
1516
1517 ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO);
1518
1519 /*
1520 * Now that we have won arbitration, start Selection process, asserting
1521 * the host and target ID's on the SCSI bus.
1522 */
1523
1524 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id)));
1525
1526 /*
1527 * Raise ATN while SEL is true before BSY goes false from arbitration,
1528 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1529 * phase immediately after selection.
1530 */
1531
1532 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY |
1533 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL ));
1534 NCR5380_write(MODE_REG, MR_BASE);
1535
1536 /*
1537 * Reselect interrupts must be turned off prior to the dropping of BSY,
1538 * otherwise we will trigger an interrupt.
1539 */
1540
1541 if (hostdata->connected) {
1542 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1543 return -1;
1544 }
1545
1546 NCR5380_write(SELECT_ENABLE_REG, 0);
1547
1548 /*
1549 * The initiator shall then wait at least two deskew delays and release
1550 * the BSY signal.
1551 */
1552 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1553
1554 /* Reset BSY */
1555 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA |
1556 ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1557
1558 /*
1559 * Something weird happens when we cease to drive BSY - looks
1560 * like the board/chip is letting us do another read before the
1561 * appropriate propagation delay has expired, and we're confusing
1562 * a BSY signal from ourselves as the target's response to SELECTION.
1563 *
1564 * A small delay (the 'C++' frontend breaks the pipeline with an
1565 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1566 * tighter 'C' code breaks and requires this) solves the problem -
1567 * the 1 us delay is arbitrary, and only used because this delay will
1568 * be the same on other platforms and since it works here, it should
1569 * work there.
1570 *
1571 * wingel suggests that this could be due to failing to wait
1572 * one deskew delay.
1573 */
1574
1575 udelay(1);
1576
1577 SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
1578
1579 /*
1580 * The SCSI specification calls for a 250 ms timeout for the actual
1581 * selection.
1582 */
1583
1584 timeout = jiffies + 25;
1585
1586 /*
1587 * XXX very interesting - we're seeing a bounce where the BSY we
1588 * asserted is being reflected / still asserted (propagation delay?)
1589 * and it's detecting as true. Sigh.
1590 */
1591
1592#if 0
1593 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1594 * IO while SEL is true. But again, there are some disks out the in the
1595 * world that do that nevertheless. (Somebody claimed that this announces
1596 * reselection capability of the target.) So we better skip that test and
1597 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-)
1598 */
1599
1600 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) &
1601 (SR_BSY | SR_IO)));
1602
1603 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) ==
1604 (SR_SEL | SR_IO)) {
1605 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1606 NCR5380_reselect(instance);
1607 printk (KERN_ERR "scsi%d: reselection after won arbitration?\n",
1608 HOSTNO);
1609 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1610 return -1;
1611 }
1612#else
1613 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY));
1614#endif
1615
1616 /*
1617 * No less than two deskew delays after the initiator detects the
1618 * BSY signal is true, it shall release the SEL signal and may
1619 * change the DATA BUS. -wingel
1620 */
1621
1622 udelay(1);
1623
1624 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1625
1626 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1627 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1628 if (hostdata->targets_present & (1 << cmd->device->id)) {
1629 printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO);
1630 if (hostdata->restart_select)
1631 printk(KERN_NOTICE "\trestart select\n");
1632 NCR_PRINT(NDEBUG_ANY);
1633 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1634 return -1;
1635 }
1636 cmd->result = DID_BAD_TARGET << 16;
1637#ifdef NCR5380_STATS
1638 collect_stats(hostdata, cmd);
1639#endif
1640#ifdef SUPPORT_TAGS
1641 cmd_free_tag( cmd );
1642#endif
1643 cmd->scsi_done(cmd);
1644 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1645 SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO);
1646 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1647 return 0;
1648 }
1649
1650 hostdata->targets_present |= (1 << cmd->device->id);
1651
1652 /*
1653 * Since we followed the SCSI spec, and raised ATN while SEL
1654 * was true but before BSY was false during selection, the information
1655 * transfer phase should be a MESSAGE OUT phase so that we can send the
1656 * IDENTIFY message.
1657 *
1658 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1659 * message (2 bytes) with a tag ID that we increment with every command
1660 * until it wraps back to 0.
1661 *
1662 * XXX - it turns out that there are some broken SCSI-II devices,
1663 * which claim to support tagged queuing but fail when more than
1664 * some number of commands are issued at once.
1665 */
1666
1667 /* Wait for start of REQ/ACK handshake */
1668 while (!(NCR5380_read(STATUS_REG) & SR_REQ));
1669
1670 SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1671 HOSTNO, cmd->device->id);
1672 tmp[0] = IDENTIFY(1, cmd->device->lun);
1673
1674#ifdef SUPPORT_TAGS
1675 if (cmd->tag != TAG_NONE) {
1676 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
1677 tmp[2] = cmd->tag;
1678 len = 3;
1679 } else
1680 len = 1;
1681#else
1682 len = 1;
1683 cmd->tag=0;
1684#endif /* SUPPORT_TAGS */
1685
1686 /* Send message(s) */
1687 data = tmp;
1688 phase = PHASE_MSGOUT;
1689 NCR5380_transfer_pio(instance, &phase, &len, &data);
1690 SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO);
1691 /* XXX need to handle errors here */
1692 hostdata->connected = cmd;
1693#ifndef SUPPORT_TAGS
1694 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1695#endif
1696
1697 initialize_SCp(cmd);
1698
1699
1700 return 0;
1701}
1702
1703/*
1704 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1705 * unsigned char *phase, int *count, unsigned char **data)
1706 *
1707 * Purpose : transfers data in given phase using polled I/O
1708 *
1709 * Inputs : instance - instance of driver, *phase - pointer to
1710 * what phase is expected, *count - pointer to number of
1711 * bytes to transfer, **data - pointer to data pointer.
1712 *
1713 * Returns : -1 when different phase is entered without transferring
1714 * maximum number of bytes, 0 if all bytes are transfered or exit
1715 * is in same phase.
1716 *
1717 * Also, *phase, *count, *data are modified in place.
1718 *
1719 * XXX Note : handling for bus free may be useful.
1720 */
1721
1722/*
1723 * Note : this code is not as quick as it could be, however it
1724 * IS 100% reliable, and for the actual data transfer where speed
1725 * counts, we will always do a pseudo DMA or DMA transfer.
1726 */
1727
1728static int NCR5380_transfer_pio( struct Scsi_Host *instance,
1729 unsigned char *phase, int *count,
1730 unsigned char **data)
1731{
1732 register unsigned char p = *phase, tmp;
1733 register int c = *count;
1734 register unsigned char *d = *data;
1735
1736 /*
1737 * The NCR5380 chip will only drive the SCSI bus when the
1738 * phase specified in the appropriate bits of the TARGET COMMAND
1739 * REGISTER match the STATUS REGISTER
1740 */
1741
1742 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1743
1744 do {
1745 /*
1746 * Wait for assertion of REQ, after which the phase bits will be
1747 * valid
1748 */
1749 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ));
1750
1751 HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO);
1752
1753 /* Check for phase mismatch */
1754 if ((tmp & PHASE_MASK) != p) {
1755 PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO);
1756 NCR_PRINT_PHASE(NDEBUG_PIO);
1757 break;
1758 }
1759
1760 /* Do actual transfer from SCSI bus to / from memory */
1761 if (!(p & SR_IO))
1762 NCR5380_write(OUTPUT_DATA_REG, *d);
1763 else
1764 *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1765
1766 ++d;
1767
1768 /*
1769 * The SCSI standard suggests that in MSGOUT phase, the initiator
1770 * should drop ATN on the last byte of the message phase
1771 * after REQ has been asserted for the handshake but before
1772 * the initiator raises ACK.
1773 */
1774
1775 if (!(p & SR_IO)) {
1776 if (!((p & SR_MSG) && c > 1)) {
1777 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1778 ICR_ASSERT_DATA);
1779 NCR_PRINT(NDEBUG_PIO);
1780 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1781 ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1782 } else {
1783 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1784 ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1785 NCR_PRINT(NDEBUG_PIO);
1786 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1787 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1788 }
1789 } else {
1790 NCR_PRINT(NDEBUG_PIO);
1791 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1792 }
1793
1794 while (NCR5380_read(STATUS_REG) & SR_REQ);
1795
1796 HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO);
1797
1798/*
1799 * We have several special cases to consider during REQ/ACK handshaking :
1800 * 1. We were in MSGOUT phase, and we are on the last byte of the
1801 * message. ATN must be dropped as ACK is dropped.
1802 *
1803 * 2. We are in a MSGIN phase, and we are on the last byte of the
1804 * message. We must exit with ACK asserted, so that the calling
1805 * code may raise ATN before dropping ACK to reject the message.
1806 *
1807 * 3. ACK and ATN are clear and the target may proceed as normal.
1808 */
1809 if (!(p == PHASE_MSGIN && c == 1)) {
1810 if (p == PHASE_MSGOUT && c > 1)
1811 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1812 else
1813 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1814 }
1815 } while (--c);
1816
1817 PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c);
1818
1819 *count = c;
1820 *data = d;
1821 tmp = NCR5380_read(STATUS_REG);
1822 /* The phase read from the bus is valid if either REQ is (already)
1823 * asserted or if ACK hasn't been released yet. The latter is the case if
1824 * we're in MSGIN and all wanted bytes have been received. */
1825 if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
1826 *phase = tmp & PHASE_MASK;
1827 else
1828 *phase = PHASE_UNKNOWN;
1829
1830 if (!c || (*phase == p))
1831 return 0;
1832 else
1833 return -1;
1834}
1835
1836/*
1837 * Function : do_abort (Scsi_Host *host)
1838 *
1839 * Purpose : abort the currently established nexus. Should only be
1840 * called from a routine which can drop into a
1841 *
1842 * Returns : 0 on success, -1 on failure.
1843 */
1844
1845static int do_abort (struct Scsi_Host *host)
1846{
1847 unsigned char tmp, *msgptr, phase;
1848 int len;
1849
1850 /* Request message out phase */
1851 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1852
1853 /*
1854 * Wait for the target to indicate a valid phase by asserting
1855 * REQ. Once this happens, we'll have either a MSGOUT phase
1856 * and can immediately send the ABORT message, or we'll have some
1857 * other phase and will have to source/sink data.
1858 *
1859 * We really don't care what value was on the bus or what value
1860 * the target sees, so we just handshake.
1861 */
1862
1863 while (!(tmp = NCR5380_read(STATUS_REG)) & SR_REQ);
1864
1865 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1866
1867 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1868 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
1869 ICR_ASSERT_ACK);
1870 while (NCR5380_read(STATUS_REG) & SR_REQ);
1871 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1872 }
1873
1874 tmp = ABORT;
1875 msgptr = &tmp;
1876 len = 1;
1877 phase = PHASE_MSGOUT;
1878 NCR5380_transfer_pio (host, &phase, &len, &msgptr);
1879
1880 /*
1881 * If we got here, and the command completed successfully,
1882 * we're about to go into bus free state.
1883 */
1884
1885 return len ? -1 : 0;
1886}
1887
1888#if defined(REAL_DMA)
1889/*
1890 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1891 * unsigned char *phase, int *count, unsigned char **data)
1892 *
1893 * Purpose : transfers data in given phase using either real
1894 * or pseudo DMA.
1895 *
1896 * Inputs : instance - instance of driver, *phase - pointer to
1897 * what phase is expected, *count - pointer to number of
1898 * bytes to transfer, **data - pointer to data pointer.
1899 *
1900 * Returns : -1 when different phase is entered without transferring
1901 * maximum number of bytes, 0 if all bytes or transfered or exit
1902 * is in same phase.
1903 *
1904 * Also, *phase, *count, *data are modified in place.
1905 *
1906 */
1907
1908
1909static int NCR5380_transfer_dma( struct Scsi_Host *instance,
1910 unsigned char *phase, int *count,
1911 unsigned char **data)
1912{
1913 SETUP_HOSTDATA(instance);
1914 register int c = *count;
1915 register unsigned char p = *phase;
1916 register unsigned char *d = *data;
1917 unsigned char tmp;
1918 unsigned long flags;
1919
1920 if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1921 *phase = tmp;
1922 return -1;
1923 }
1924
1925 if (atari_read_overruns && (p & SR_IO)) {
1926 c -= atari_read_overruns;
1927 }
1928
1929 DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1930 HOSTNO, (p & SR_IO) ? "reading" : "writing",
1931 c, (p & SR_IO) ? "to" : "from", d);
1932
1933 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1934
1935#ifdef REAL_DMA
1936 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1937#endif /* def REAL_DMA */
1938
1939 if (IS_A_TT()) {
1940 /* On the Medusa, it is a must to initialize the DMA before
1941 * starting the NCR. This is also the cleaner way for the TT.
1942 */
1943 local_irq_save(flags);
1944 hostdata->dma_len = (p & SR_IO) ?
1945 NCR5380_dma_read_setup(instance, d, c) :
1946 NCR5380_dma_write_setup(instance, d, c);
1947 local_irq_restore(flags);
1948 }
1949
1950 if (p & SR_IO)
1951 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1952 else {
1953 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1954 NCR5380_write(START_DMA_SEND_REG, 0);
1955 }
1956
1957 if (!IS_A_TT()) {
1958 /* On the Falcon, the DMA setup must be done after the last */
1959 /* NCR access, else the DMA setup gets trashed!
1960 */
1961 local_irq_save(flags);
1962 hostdata->dma_len = (p & SR_IO) ?
1963 NCR5380_dma_read_setup(instance, d, c) :
1964 NCR5380_dma_write_setup(instance, d, c);
1965 local_irq_restore(flags);
1966 }
1967 return 0;
1968}
1969#endif /* defined(REAL_DMA) */
1970
1971/*
1972 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1973 *
1974 * Purpose : run through the various SCSI phases and do as the target
1975 * directs us to. Operates on the currently connected command,
1976 * instance->connected.
1977 *
1978 * Inputs : instance, instance for which we are doing commands
1979 *
1980 * Side effects : SCSI things happen, the disconnected queue will be
1981 * modified if a command disconnects, *instance->connected will
1982 * change.
1983 *
1984 * XXX Note : we need to watch for bus free or a reset condition here
1985 * to recover from an unexpected bus free condition.
1986 */
1987
1988static void NCR5380_information_transfer (struct Scsi_Host *instance)
1989{
1990 SETUP_HOSTDATA(instance);
1991 unsigned long flags;
1992 unsigned char msgout = NOP;
1993 int sink = 0;
1994 int len;
1995#if defined(REAL_DMA)
1996 int transfersize;
1997#endif
1998 unsigned char *data;
1999 unsigned char phase, tmp, extended_msg[10], old_phase=0xff;
2000 Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2001
2002 while (1) {
2003 tmp = NCR5380_read(STATUS_REG);
2004 /* We only have a valid SCSI phase when REQ is asserted */
2005 if (tmp & SR_REQ) {
2006 phase = (tmp & PHASE_MASK);
2007 if (phase != old_phase) {
2008 old_phase = phase;
2009 NCR_PRINT_PHASE(NDEBUG_INFORMATION);
2010 }
2011
2012 if (sink && (phase != PHASE_MSGOUT)) {
2013 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2014
2015 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
2016 ICR_ASSERT_ACK);
2017 while (NCR5380_read(STATUS_REG) & SR_REQ);
2018 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2019 ICR_ASSERT_ATN);
2020 sink = 0;
2021 continue;
2022 }
2023
2024 switch (phase) {
2025 case PHASE_DATAOUT:
2026#if (NDEBUG & NDEBUG_NO_DATAOUT)
2027 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2028 "aborted\n", HOSTNO);
2029 sink = 1;
2030 do_abort(instance);
2031 cmd->result = DID_ERROR << 16;
2032 cmd->done(cmd);
2033 return;
2034#endif
2035 case PHASE_DATAIN:
2036 /*
2037 * If there is no room left in the current buffer in the
2038 * scatter-gather list, move onto the next one.
2039 */
2040
2041 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2042 ++cmd->SCp.buffer;
2043 --cmd->SCp.buffers_residual;
2044 cmd->SCp.this_residual = cmd->SCp.buffer->length;
2045 cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+
2046 cmd->SCp.buffer->offset;
2047 /* ++roman: Try to merge some scatter-buffers if
2048 * they are at contiguous physical addresses.
2049 */
2050 merge_contiguous_buffers( cmd );
2051 INF_PRINTK("scsi%d: %d bytes and %d buffers left\n",
2052 HOSTNO, cmd->SCp.this_residual,
2053 cmd->SCp.buffers_residual);
2054 }
2055
2056 /*
2057 * The preferred transfer method is going to be
2058 * PSEUDO-DMA for systems that are strictly PIO,
2059 * since we can let the hardware do the handshaking.
2060 *
2061 * For this to work, we need to know the transfersize
2062 * ahead of time, since the pseudo-DMA code will sit
2063 * in an unconditional loop.
2064 */
2065
2066/* ++roman: I suggest, this should be
2067 * #if def(REAL_DMA)
2068 * instead of leaving REAL_DMA out.
2069 */
2070
2071#if defined(REAL_DMA)
2072 if (!cmd->device->borken &&
2073 (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) {
2074 len = transfersize;
2075 cmd->SCp.phase = phase;
2076 if (NCR5380_transfer_dma(instance, &phase,
2077 &len, (unsigned char **) &cmd->SCp.ptr)) {
2078 /*
2079 * If the watchdog timer fires, all future
2080 * accesses to this device will use the
2081 * polled-IO. */
2082 printk(KERN_NOTICE "scsi%d: switching target %d "
2083 "lun %d to slow handshake\n", HOSTNO,
2084 cmd->device->id, cmd->device->lun);
2085 cmd->device->borken = 1;
2086 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2087 ICR_ASSERT_ATN);
2088 sink = 1;
2089 do_abort(instance);
2090 cmd->result = DID_ERROR << 16;
2091 cmd->done(cmd);
2092 /* XXX - need to source or sink data here, as appropriate */
2093 } else {
2094#ifdef REAL_DMA
2095 /* ++roman: When using real DMA,
2096 * information_transfer() should return after
2097 * starting DMA since it has nothing more to
2098 * do.
2099 */
2100 return;
2101#else
2102 cmd->SCp.this_residual -= transfersize - len;
2103#endif
2104 }
2105 } else
2106#endif /* defined(REAL_DMA) */
2107 NCR5380_transfer_pio(instance, &phase,
2108 (int *) &cmd->SCp.this_residual, (unsigned char **)
2109 &cmd->SCp.ptr);
2110 break;
2111 case PHASE_MSGIN:
2112 len = 1;
2113 data = &tmp;
2114 NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */
2115 NCR5380_transfer_pio(instance, &phase, &len, &data);
2116 cmd->SCp.Message = tmp;
2117
2118 switch (tmp) {
2119 /*
2120 * Linking lets us reduce the time required to get the
2121 * next command out to the device, hopefully this will
2122 * mean we don't waste another revolution due to the delays
2123 * required by ARBITRATION and another SELECTION.
2124 *
2125 * In the current implementation proposal, low level drivers
2126 * merely have to start the next command, pointed to by
2127 * next_link, done() is called as with unlinked commands.
2128 */
2129#ifdef LINKED
2130 case LINKED_CMD_COMPLETE:
2131 case LINKED_FLG_CMD_COMPLETE:
2132 /* Accept message by clearing ACK */
2133 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2134
2135 LNK_PRINTK("scsi%d: target %d lun %d linked command "
2136 "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun);
2137
2138 /* Enable reselect interrupts */
2139 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2140 /*
2141 * Sanity check : A linked command should only terminate
2142 * with one of these messages if there are more linked
2143 * commands available.
2144 */
2145
2146 if (!cmd->next_link) {
2147 printk(KERN_NOTICE "scsi%d: target %d lun %d "
2148 "linked command complete, no next_link\n",
2149 HOSTNO, cmd->device->id, cmd->device->lun);
2150 sink = 1;
2151 do_abort (instance);
2152 return;
2153 }
2154
2155 initialize_SCp(cmd->next_link);
2156 /* The next command is still part of this process; copy it
2157 * and don't free it! */
2158 cmd->next_link->tag = cmd->tag;
2159 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2160 LNK_PRINTK("scsi%d: target %d lun %d linked request "
2161 "done, calling scsi_done().\n",
2162 HOSTNO, cmd->device->id, cmd->device->lun);
2163#ifdef NCR5380_STATS
2164 collect_stats(hostdata, cmd);
2165#endif
2166 cmd->scsi_done(cmd);
2167 cmd = hostdata->connected;
2168 break;
2169#endif /* def LINKED */
2170 case ABORT:
2171 case COMMAND_COMPLETE:
2172 /* Accept message by clearing ACK */
2173 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2174 /* ++guenther: possible race with Falcon locking */
2175 falcon_dont_release++;
2176 hostdata->connected = NULL;
2177 QU_PRINTK("scsi%d: command for target %d, lun %d "
2178 "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
2179#ifdef SUPPORT_TAGS
2180 cmd_free_tag( cmd );
2181 if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
2182 /* Turn a QUEUE FULL status into BUSY, I think the
2183 * mid level cannot handle QUEUE FULL :-( (The
2184 * command is retried after BUSY). Also update our
2185 * queue size to the number of currently issued
2186 * commands now.
2187 */
2188 /* ++Andreas: the mid level code knows about
2189 QUEUE_FULL now. */
2190 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
2191 TAG_PRINTK("scsi%d: target %d lun %d returned "
2192 "QUEUE_FULL after %d commands\n",
2193 HOSTNO, cmd->device->id, cmd->device->lun,
2194 ta->nr_allocated);
2195 if (ta->queue_size > ta->nr_allocated)
2196 ta->nr_allocated = ta->queue_size;
2197 }
2198#else
2199 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2200#endif
2201 /* Enable reselect interrupts */
2202 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2203
2204 /*
2205 * I'm not sure what the correct thing to do here is :
2206 *
2207 * If the command that just executed is NOT a request
2208 * sense, the obvious thing to do is to set the result
2209 * code to the values of the stored parameters.
2210 *
2211 * If it was a REQUEST SENSE command, we need some way to
2212 * differentiate between the failure code of the original
2213 * and the failure code of the REQUEST sense - the obvious
2214 * case is success, where we fall through and leave the
2215 * result code unchanged.
2216 *
2217 * The non-obvious place is where the REQUEST SENSE failed
2218 */
2219
2220 if (cmd->cmnd[0] != REQUEST_SENSE)
2221 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2222 else if (status_byte(cmd->SCp.Status) != GOOD)
2223 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2224
2225#ifdef AUTOSENSE
2226 if ((cmd->cmnd[0] != REQUEST_SENSE) &&
2227 (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2228 ASEN_PRINTK("scsi%d: performing request sense\n",
2229 HOSTNO);
2230 cmd->cmnd[0] = REQUEST_SENSE;
2231 cmd->cmnd[1] &= 0xe0;
2232 cmd->cmnd[2] = 0;
2233 cmd->cmnd[3] = 0;
2234 cmd->cmnd[4] = sizeof(cmd->sense_buffer);
2235 cmd->cmnd[5] = 0;
2236 cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]);
2237
2238 cmd->use_sg = 0;
2239 /* this is initialized from initialize_SCp
2240 cmd->SCp.buffer = NULL;
2241 cmd->SCp.buffers_residual = 0;
2242 */
2243 cmd->request_buffer = (char *) cmd->sense_buffer;
2244 cmd->request_bufflen = sizeof(cmd->sense_buffer);
2245
2246 local_irq_save(flags);
2247 LIST(cmd,hostdata->issue_queue);
2248 NEXT(cmd) = hostdata->issue_queue;
2249 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2250 local_irq_restore(flags);
2251 QU_PRINTK("scsi%d: REQUEST SENSE added to head of "
2252 "issue queue\n", H_NO(cmd));
2253 } else
2254#endif /* def AUTOSENSE */
2255 {
2256#ifdef NCR5380_STATS
2257 collect_stats(hostdata, cmd);
2258#endif
2259 cmd->scsi_done(cmd);
2260 }
2261
2262 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2263 /*
2264 * Restore phase bits to 0 so an interrupted selection,
2265 * arbitration can resume.
2266 */
2267 NCR5380_write(TARGET_COMMAND_REG, 0);
2268
2269 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2270 barrier();
2271
2272 falcon_dont_release--;
2273 /* ++roman: For Falcon SCSI, release the lock on the
2274 * ST-DMA here if no other commands are waiting on the
2275 * disconnected queue.
2276 */
2277 falcon_release_lock_if_possible( hostdata );
2278 return;
2279 case MESSAGE_REJECT:
2280 /* Accept message by clearing ACK */
2281 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2282 /* Enable reselect interrupts */
2283 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2284 switch (hostdata->last_message) {
2285 case HEAD_OF_QUEUE_TAG:
2286 case ORDERED_QUEUE_TAG:
2287 case SIMPLE_QUEUE_TAG:
2288 /* The target obviously doesn't support tagged
2289 * queuing, even though it announced this ability in
2290 * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2291 * clear 'tagged_supported' and lock the LUN, since
2292 * the command is treated as untagged further on.
2293 */
2294 cmd->device->tagged_supported = 0;
2295 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2296 cmd->tag = TAG_NONE;
2297 TAG_PRINTK("scsi%d: target %d lun %d rejected "
2298 "QUEUE_TAG message; tagged queuing "
2299 "disabled\n",
2300 HOSTNO, cmd->device->id, cmd->device->lun);
2301 break;
2302 }
2303 break;
2304 case DISCONNECT:
2305 /* Accept message by clearing ACK */
2306 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2307 local_irq_save(flags);
2308 cmd->device->disconnect = 1;
2309 LIST(cmd,hostdata->disconnected_queue);
2310 NEXT(cmd) = hostdata->disconnected_queue;
2311 hostdata->connected = NULL;
2312 hostdata->disconnected_queue = cmd;
2313 local_irq_restore(flags);
2314 QU_PRINTK("scsi%d: command for target %d lun %d was "
2315 "moved from connected to the "
2316 "disconnected_queue\n", HOSTNO,
2317 cmd->device->id, cmd->device->lun);
2318 /*
2319 * Restore phase bits to 0 so an interrupted selection,
2320 * arbitration can resume.
2321 */
2322 NCR5380_write(TARGET_COMMAND_REG, 0);
2323
2324 /* Enable reselect interrupts */
2325 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2326 /* Wait for bus free to avoid nasty timeouts */
2327 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2328 barrier();
2329 return;
2330 /*
2331 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2332 * operation, in violation of the SCSI spec so we can safely
2333 * ignore SAVE/RESTORE pointers calls.
2334 *
2335 * Unfortunately, some disks violate the SCSI spec and
2336 * don't issue the required SAVE_POINTERS message before
2337 * disconnecting, and we have to break spec to remain
2338 * compatible.
2339 */
2340 case SAVE_POINTERS:
2341 case RESTORE_POINTERS:
2342 /* Accept message by clearing ACK */
2343 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2344 /* Enable reselect interrupts */
2345 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2346 break;
2347 case EXTENDED_MESSAGE:
2348/*
2349 * Extended messages are sent in the following format :
2350 * Byte
2351 * 0 EXTENDED_MESSAGE == 1
2352 * 1 length (includes one byte for code, doesn't
2353 * include first two bytes)
2354 * 2 code
2355 * 3..length+1 arguments
2356 *
2357 * Start the extended message buffer with the EXTENDED_MESSAGE
db9dff32005-04-03 14:53:59 -05002358 * byte, since scsi_print_msg() wants the whole thing.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002359 */
2360 extended_msg[0] = EXTENDED_MESSAGE;
2361 /* Accept first byte by clearing ACK */
2362 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2363
2364 EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO);
2365
2366 len = 2;
2367 data = extended_msg + 1;
2368 phase = PHASE_MSGIN;
2369 NCR5380_transfer_pio(instance, &phase, &len, &data);
2370 EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2371 (int)extended_msg[1], (int)extended_msg[2]);
2372
2373 if (!len && extended_msg[1] <=
2374 (sizeof (extended_msg) - 1)) {
2375 /* Accept third byte by clearing ACK */
2376 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2377 len = extended_msg[1] - 1;
2378 data = extended_msg + 3;
2379 phase = PHASE_MSGIN;
2380
2381 NCR5380_transfer_pio(instance, &phase, &len, &data);
2382 EXT_PRINTK("scsi%d: message received, residual %d\n",
2383 HOSTNO, len);
2384
2385 switch (extended_msg[2]) {
2386 case EXTENDED_SDTR:
2387 case EXTENDED_WDTR:
2388 case EXTENDED_MODIFY_DATA_POINTER:
2389 case EXTENDED_EXTENDED_IDENTIFY:
2390 tmp = 0;
2391 }
2392 } else if (len) {
2393 printk(KERN_NOTICE "scsi%d: error receiving "
2394 "extended message\n", HOSTNO);
2395 tmp = 0;
2396 } else {
2397 printk(KERN_NOTICE "scsi%d: extended message "
2398 "code %02x length %d is too long\n",
2399 HOSTNO, extended_msg[2], extended_msg[1]);
2400 tmp = 0;
2401 }
2402 /* Fall through to reject message */
2403
2404 /*
2405 * If we get something weird that we aren't expecting,
2406 * reject it.
2407 */
2408 default:
2409 if (!tmp) {
2410 printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO);
db9dff32005-04-03 14:53:59 -05002411 scsi_print_msg (extended_msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002412 printk("\n");
2413 } else if (tmp != EXTENDED_MESSAGE)
2414 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2415 "message %02x from target %d, lun %d\n",
2416 HOSTNO, tmp, cmd->device->id, cmd->device->lun);
2417 else
2418 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2419 "extended message "
2420 "code %02x, length %d from target %d, lun %d\n",
2421 HOSTNO, extended_msg[1], extended_msg[0],
2422 cmd->device->id, cmd->device->lun);
2423
2424
2425 msgout = MESSAGE_REJECT;
2426 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2427 ICR_ASSERT_ATN);
2428 break;
2429 } /* switch (tmp) */
2430 break;
2431 case PHASE_MSGOUT:
2432 len = 1;
2433 data = &msgout;
2434 hostdata->last_message = msgout;
2435 NCR5380_transfer_pio(instance, &phase, &len, &data);
2436 if (msgout == ABORT) {
2437#ifdef SUPPORT_TAGS
2438 cmd_free_tag( cmd );
2439#else
2440 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2441#endif
2442 hostdata->connected = NULL;
2443 cmd->result = DID_ERROR << 16;
2444#ifdef NCR5380_STATS
2445 collect_stats(hostdata, cmd);
2446#endif
2447 cmd->scsi_done(cmd);
2448 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2449 falcon_release_lock_if_possible( hostdata );
2450 return;
2451 }
2452 msgout = NOP;
2453 break;
2454 case PHASE_CMDOUT:
2455 len = cmd->cmd_len;
2456 data = cmd->cmnd;
2457 /*
2458 * XXX for performance reasons, on machines with a
2459 * PSEUDO-DMA architecture we should probably
2460 * use the dma transfer function.
2461 */
2462 NCR5380_transfer_pio(instance, &phase, &len,
2463 &data);
2464 break;
2465 case PHASE_STATIN:
2466 len = 1;
2467 data = &tmp;
2468 NCR5380_transfer_pio(instance, &phase, &len, &data);
2469 cmd->SCp.Status = tmp;
2470 break;
2471 default:
2472 printk("scsi%d: unknown phase\n", HOSTNO);
2473 NCR_PRINT(NDEBUG_ANY);
2474 } /* switch(phase) */
2475 } /* if (tmp * SR_REQ) */
2476 } /* while (1) */
2477}
2478
2479/*
2480 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2481 *
2482 * Purpose : does reselection, initializing the instance->connected
2483 * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2484 * nexus has been reestablished,
2485 *
2486 * Inputs : instance - this instance of the NCR5380.
2487 *
2488 */
2489
2490
2491static void NCR5380_reselect (struct Scsi_Host *instance)
2492{
2493 SETUP_HOSTDATA(instance);
2494 unsigned char target_mask;
2495 unsigned char lun, phase;
2496 int len;
2497#ifdef SUPPORT_TAGS
2498 unsigned char tag;
2499#endif
2500 unsigned char msg[3];
2501 unsigned char *data;
2502 Scsi_Cmnd *tmp = NULL, *prev;
2503/* unsigned long flags; */
2504
2505 /*
2506 * Disable arbitration, etc. since the host adapter obviously
2507 * lost, and tell an interrupted NCR5380_select() to restart.
2508 */
2509
2510 NCR5380_write(MODE_REG, MR_BASE);
2511 hostdata->restart_select = 1;
2512
2513 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2514
2515 RSL_PRINTK("scsi%d: reselect\n", HOSTNO);
2516
2517 /*
2518 * At this point, we have detected that our SCSI ID is on the bus,
2519 * SEL is true and BSY was false for at least one bus settle delay
2520 * (400 ns).
2521 *
2522 * We must assert BSY ourselves, until the target drops the SEL
2523 * signal.
2524 */
2525
2526 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2527
2528 while (NCR5380_read(STATUS_REG) & SR_SEL);
2529 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2530
2531 /*
2532 * Wait for target to go into MSGIN.
2533 */
2534
2535 while (!(NCR5380_read(STATUS_REG) & SR_REQ));
2536
2537 len = 1;
2538 data = msg;
2539 phase = PHASE_MSGIN;
2540 NCR5380_transfer_pio(instance, &phase, &len, &data);
2541
2542 if (!(msg[0] & 0x80)) {
2543 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
db9dff32005-04-03 14:53:59 -05002544 scsi_print_msg(msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002545 do_abort(instance);
2546 return;
2547 }
2548 lun = (msg[0] & 0x07);
2549
2550#ifdef SUPPORT_TAGS
2551 /* If the phase is still MSGIN, the target wants to send some more
2552 * messages. In case it supports tagged queuing, this is probably a
2553 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2554 */
2555 tag = TAG_NONE;
2556 if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
2557 /* Accept previous IDENTIFY message by clearing ACK */
2558 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE );
2559 len = 2;
2560 data = msg+1;
2561 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2562 msg[1] == SIMPLE_QUEUE_TAG)
2563 tag = msg[2];
2564 TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at "
2565 "reselection\n", HOSTNO, target_mask, lun, tag);
2566 }
2567#endif
2568
2569 /*
2570 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2571 * just reestablished, and remove it from the disconnected queue.
2572 */
2573
2574 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL;
2575 tmp; prev = tmp, tmp = NEXT(tmp) ) {
2576 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2577#ifdef SUPPORT_TAGS
2578 && (tag == tmp->tag)
2579#endif
2580 ) {
2581 /* ++guenther: prevent race with falcon_release_lock */
2582 falcon_dont_release++;
2583 if (prev) {
2584 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2585 NEXT(prev) = NEXT(tmp);
2586 } else {
2587 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
2588 hostdata->disconnected_queue = NEXT(tmp);
2589 }
2590 NEXT(tmp) = NULL;
2591 break;
2592 }
2593 }
2594
2595 if (!tmp) {
2596 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
2597#ifdef SUPPORT_TAGS
2598 "tag %d "
2599#endif
2600 "not in disconnected_queue.\n",
2601 HOSTNO, target_mask, lun
2602#ifdef SUPPORT_TAGS
2603 , tag
2604#endif
2605 );
2606 /*
2607 * Since we have an established nexus that we can't do anything
2608 * with, we must abort it.
2609 */
2610 do_abort(instance);
2611 return;
2612 }
2613
2614 /* Accept message by clearing ACK */
2615 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2616
2617 hostdata->connected = tmp;
2618 RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n",
2619 HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
2620 falcon_dont_release--;
2621}
2622
2623
2624/*
2625 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2626 *
2627 * Purpose : abort a command
2628 *
2629 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2630 * host byte of the result field to, if zero DID_ABORTED is
2631 * used.
2632 *
2633 * Returns : 0 - success, -1 on failure.
2634 *
2635 * XXX - there is no way to abort the command that is currently
2636 * connected, you have to wait for it to complete. If this is
2637 * a problem, we could implement longjmp() / setjmp(), setjmp()
2638 * called where the loop started in NCR5380_main().
2639 */
2640
2641static
2642int NCR5380_abort (Scsi_Cmnd *cmd)
2643{
2644 struct Scsi_Host *instance = cmd->device->host;
2645 SETUP_HOSTDATA(instance);
2646 Scsi_Cmnd *tmp, **prev;
2647 unsigned long flags;
2648
2649 printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO);
db9dff32005-04-03 14:53:59 -05002650 scsi_print_command(cmd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002651
2652 NCR5380_print_status (instance);
2653
2654 local_irq_save(flags);
2655
2656 if (!IS_A_TT() && !falcon_got_lock)
2657 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n",
2658 HOSTNO);
2659
2660 ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2661 NCR5380_read(BUS_AND_STATUS_REG),
2662 NCR5380_read(STATUS_REG));
2663
2664#if 1
2665/*
2666 * Case 1 : If the command is the currently executing command,
2667 * we'll set the aborted flag and return control so that
2668 * information transfer routine can exit cleanly.
2669 */
2670
2671 if (hostdata->connected == cmd) {
2672
2673 ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO);
2674/*
2675 * We should perform BSY checking, and make sure we haven't slipped
2676 * into BUS FREE.
2677 */
2678
2679/* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2680/*
2681 * Since we can't change phases until we've completed the current
2682 * handshake, we have to source or sink a byte of data if the current
2683 * phase is not MSGOUT.
2684 */
2685
2686/*
2687 * Return control to the executing NCR drive so we can clear the
2688 * aborted flag and get back into our main loop.
2689 */
2690
2691 if (do_abort(instance) == 0) {
2692 hostdata->aborted = 1;
2693 hostdata->connected = NULL;
2694 cmd->result = DID_ABORT << 16;
2695#ifdef SUPPORT_TAGS
2696 cmd_free_tag( cmd );
2697#else
2698 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2699#endif
2700 local_irq_restore(flags);
2701 cmd->scsi_done(cmd);
2702 falcon_release_lock_if_possible( hostdata );
2703 return SCSI_ABORT_SUCCESS;
2704 } else {
2705/* local_irq_restore(flags); */
2706 printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2707 return SCSI_ABORT_ERROR;
2708 }
2709 }
2710#endif
2711
2712/*
2713 * Case 2 : If the command hasn't been issued yet, we simply remove it
2714 * from the issue queue.
2715 */
2716 for (prev = (Scsi_Cmnd **) &(hostdata->issue_queue),
2717 tmp = (Scsi_Cmnd *) hostdata->issue_queue;
2718 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) )
2719 if (cmd == tmp) {
2720 REMOVE(5, *prev, tmp, NEXT(tmp));
2721 (*prev) = NEXT(tmp);
2722 NEXT(tmp) = NULL;
2723 tmp->result = DID_ABORT << 16;
2724 local_irq_restore(flags);
2725 ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n",
2726 HOSTNO);
2727 /* Tagged queuing note: no tag to free here, hasn't been assigned
2728 * yet... */
2729 tmp->scsi_done(tmp);
2730 falcon_release_lock_if_possible( hostdata );
2731 return SCSI_ABORT_SUCCESS;
2732 }
2733
2734/*
2735 * Case 3 : If any commands are connected, we're going to fail the abort
2736 * and let the high level SCSI driver retry at a later time or
2737 * issue a reset.
2738 *
2739 * Timeouts, and therefore aborted commands, will be highly unlikely
2740 * and handling them cleanly in this situation would make the common
2741 * case of noresets less efficient, and would pollute our code. So,
2742 * we fail.
2743 */
2744
2745 if (hostdata->connected) {
2746 local_irq_restore(flags);
2747 ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO);
2748 return SCSI_ABORT_SNOOZE;
2749 }
2750
2751/*
2752 * Case 4: If the command is currently disconnected from the bus, and
2753 * there are no connected commands, we reconnect the I_T_L or
2754 * I_T_L_Q nexus associated with it, go into message out, and send
2755 * an abort message.
2756 *
2757 * This case is especially ugly. In order to reestablish the nexus, we
2758 * need to call NCR5380_select(). The easiest way to implement this
2759 * function was to abort if the bus was busy, and let the interrupt
2760 * handler triggered on the SEL for reselect take care of lost arbitrations
2761 * where necessary, meaning interrupts need to be enabled.
2762 *
2763 * When interrupts are enabled, the queues may change - so we
2764 * can't remove it from the disconnected queue before selecting it
2765 * because that could cause a failure in hashing the nexus if that
2766 * device reselected.
2767 *
2768 * Since the queues may change, we can't use the pointers from when we
2769 * first locate it.
2770 *
2771 * So, we must first locate the command, and if NCR5380_select()
2772 * succeeds, then issue the abort, relocate the command and remove
2773 * it from the disconnected queue.
2774 */
2775
2776 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp;
2777 tmp = NEXT(tmp))
2778 if (cmd == tmp) {
2779 local_irq_restore(flags);
2780 ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO);
2781
2782 if (NCR5380_select (instance, cmd, (int) cmd->tag))
2783 return SCSI_ABORT_BUSY;
2784
2785 ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO);
2786
2787 do_abort (instance);
2788
2789 local_irq_save(flags);
2790 for (prev = (Scsi_Cmnd **) &(hostdata->disconnected_queue),
2791 tmp = (Scsi_Cmnd *) hostdata->disconnected_queue;
2792 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) )
2793 if (cmd == tmp) {
2794 REMOVE(5, *prev, tmp, NEXT(tmp));
2795 *prev = NEXT(tmp);
2796 NEXT(tmp) = NULL;
2797 tmp->result = DID_ABORT << 16;
2798 /* We must unlock the tag/LUN immediately here, since the
2799 * target goes to BUS FREE and doesn't send us another
2800 * message (COMMAND_COMPLETE or the like)
2801 */
2802#ifdef SUPPORT_TAGS
2803 cmd_free_tag( tmp );
2804#else
2805 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2806#endif
2807 local_irq_restore(flags);
2808 tmp->scsi_done(tmp);
2809 falcon_release_lock_if_possible( hostdata );
2810 return SCSI_ABORT_SUCCESS;
2811 }
2812 }
2813
2814/*
2815 * Case 5 : If we reached this point, the command was not found in any of
2816 * the queues.
2817 *
2818 * We probably reached this point because of an unlikely race condition
2819 * between the command completing successfully and the abortion code,
2820 * so we won't panic, but we will notify the user in case something really
2821 * broke.
2822 */
2823
2824 local_irq_restore(flags);
2825 printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully\n"
2826 KERN_INFO " before abortion\n", HOSTNO);
2827
2828/* Maybe it is sufficient just to release the ST-DMA lock... (if
2829 * possible at all) At least, we should check if the lock could be
2830 * released after the abort, in case it is kept due to some bug.
2831 */
2832 falcon_release_lock_if_possible( hostdata );
2833
2834 return SCSI_ABORT_NOT_RUNNING;
2835}
2836
2837
2838/*
2839 * Function : int NCR5380_reset (Scsi_Cmnd *cmd)
2840 *
2841 * Purpose : reset the SCSI bus.
2842 *
2843 * Returns : SCSI_RESET_WAKEUP
2844 *
2845 */
2846
2847static int NCR5380_bus_reset( Scsi_Cmnd *cmd)
2848{
2849 SETUP_HOSTDATA(cmd->device->host);
2850 int i;
2851 unsigned long flags;
2852#if 1
2853 Scsi_Cmnd *connected, *disconnected_queue;
2854#endif
2855
2856 if (!IS_A_TT() && !falcon_got_lock)
2857 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n",
2858 H_NO(cmd) );
2859
2860 NCR5380_print_status (cmd->device->host);
2861
2862 /* get in phase */
2863 NCR5380_write( TARGET_COMMAND_REG,
2864 PHASE_SR_TO_TCR( NCR5380_read(STATUS_REG) ));
2865 /* assert RST */
2866 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST );
2867 udelay (40);
2868 /* reset NCR registers */
2869 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE );
2870 NCR5380_write( MODE_REG, MR_BASE );
2871 NCR5380_write( TARGET_COMMAND_REG, 0 );
2872 NCR5380_write( SELECT_ENABLE_REG, 0 );
2873 /* ++roman: reset interrupt condition! otherwise no interrupts don't get
2874 * through anymore ... */
2875 (void)NCR5380_read( RESET_PARITY_INTERRUPT_REG );
2876
2877#if 1 /* XXX Should now be done by midlevel code, but it's broken XXX */
2878 /* XXX see below XXX */
2879
2880 /* MSch: old-style reset: actually abort all command processing here */
2881
2882 /* After the reset, there are no more connected or disconnected commands
2883 * and no busy units; to avoid problems with re-inserting the commands
2884 * into the issue_queue (via scsi_done()), the aborted commands are
2885 * remembered in local variables first.
2886 */
2887 local_irq_save(flags);
2888 connected = (Scsi_Cmnd *)hostdata->connected;
2889 hostdata->connected = NULL;
2890 disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue;
2891 hostdata->disconnected_queue = NULL;
2892#ifdef SUPPORT_TAGS
2893 free_all_tags();
2894#endif
2895 for( i = 0; i < 8; ++i )
2896 hostdata->busy[i] = 0;
2897#ifdef REAL_DMA
2898 hostdata->dma_len = 0;
2899#endif
2900 local_irq_restore(flags);
2901
2902 /* In order to tell the mid-level code which commands were aborted,
2903 * set the command status to DID_RESET and call scsi_done() !!!
2904 * This ultimately aborts processing of these commands in the mid-level.
2905 */
2906
2907 if ((cmd = connected)) {
2908 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2909 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2910 cmd->scsi_done( cmd );
2911 }
2912
2913 for (i = 0; (cmd = disconnected_queue); ++i) {
2914 disconnected_queue = NEXT(cmd);
2915 NEXT(cmd) = NULL;
2916 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2917 cmd->scsi_done( cmd );
2918 }
2919 if (i > 0)
2920 ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i);
2921
2922/* The Falcon lock should be released after a reset...
2923 */
2924/* ++guenther: moved to atari_scsi_reset(), to prevent a race between
2925 * unlocking and enabling dma interrupt.
2926 */
2927/* falcon_release_lock_if_possible( hostdata );*/
2928
2929 /* since all commands have been explicitly terminated, we need to tell
2930 * the midlevel code that the reset was SUCCESSFUL, and there is no
2931 * need to 'wake up' the commands by a request_sense
2932 */
2933 return SCSI_RESET_SUCCESS | SCSI_RESET_BUS_RESET;
2934#else /* 1 */
2935
2936 /* MSch: new-style reset handling: let the mid-level do what it can */
2937
2938 /* ++guenther: MID-LEVEL IS STILL BROKEN.
2939 * Mid-level is supposed to requeue all commands that were active on the
2940 * various low-level queues. In fact it does this, but that's not enough
2941 * because all these commands are subject to timeout. And if a timeout
2942 * happens for any removed command, *_abort() is called but all queues
2943 * are now empty. Abort then gives up the falcon lock, which is fatal,
2944 * since the mid-level will queue more commands and must have the lock
2945 * (it's all happening inside timer interrupt handler!!).
2946 * Even worse, abort will return NOT_RUNNING for all those commands not
2947 * on any queue, so they won't be retried ...
2948 *
2949 * Conclusion: either scsi.c disables timeout for all resetted commands
2950 * immediately, or we lose! As of linux-2.0.20 it doesn't.
2951 */
2952
2953 /* After the reset, there are no more connected or disconnected commands
2954 * and no busy units; so clear the low-level status here to avoid
2955 * conflicts when the mid-level code tries to wake up the affected
2956 * commands!
2957 */
2958
2959 if (hostdata->issue_queue)
2960 ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2961 if (hostdata->connected)
2962 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2963 if (hostdata->disconnected_queue)
2964 ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
2965
2966 local_irq_save(flags);
2967 hostdata->issue_queue = NULL;
2968 hostdata->connected = NULL;
2969 hostdata->disconnected_queue = NULL;
2970#ifdef SUPPORT_TAGS
2971 free_all_tags();
2972#endif
2973 for( i = 0; i < 8; ++i )
2974 hostdata->busy[i] = 0;
2975#ifdef REAL_DMA
2976 hostdata->dma_len = 0;
2977#endif
2978 local_irq_restore(flags);
2979
2980 /* we did no complete reset of all commands, so a wakeup is required */
2981 return SCSI_RESET_WAKEUP | SCSI_RESET_BUS_RESET;
2982#endif /* 1 */
2983}
2984
2985/* Local Variables: */
2986/* tab-width: 8 */
2987/* End: */