2 * NCR 5380 generic driver routines. These should make it *trivial*
3 * to implement 5380 SCSI drivers under Linux with a non-trantor
6 * Note that these routines also work with NR53c400 family chips.
8 * Copyright 1993, Drew Eckhardt
10 * (Unix and Linux consulting and custom programming)
14 * For more information, please consult
17 * SCSI Protocol Controller
20 * NCR Microelectronics
21 * 1635 Aeroplaza Drive
22 * Colorado Springs, CO 80916
28 * With contributions from Ray Van Tassle, Ingmar Baumgart,
29 * Ronald van Cuijlenborg, Alan Cox and others.
32 /* Ported to Atari by Roman Hodek and others. */
34 /* Adapted for the Sun 3 by Sam Creasey. */
39 * This is a generic 5380 driver. To use it on a different platform,
40 * one simply writes appropriate system specific macros (ie, data
41 * transfer - some PC's will use the I/O bus, 68K's must use
42 * memory mapped) and drops this file in their 'C' wrapper.
44 * As far as command queueing, two queues are maintained for
45 * each 5380 in the system - commands that haven't been issued yet,
46 * and commands that are currently executing. This means that an
47 * unlimited number of commands may be queued, letting
48 * more commands propagate from the higher driver levels giving higher
49 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
50 * allowing multiple commands to propagate all the way to a SCSI-II device
51 * while a command is already executing.
54 * Issues specific to the NCR5380 :
56 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
57 * piece of hardware that requires you to sit in a loop polling for
58 * the REQ signal as long as you are connected. Some devices are
59 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
60 * while doing long seek operations. [...] These
61 * broken devices are the exception rather than the rule and I'd rather
62 * spend my time optimizing for the normal case.
66 * At the heart of the design is a coroutine, NCR5380_main,
67 * which is started from a workqueue for each NCR5380 host in the
68 * system. It attempts to establish I_T_L or I_T_L_Q nexuses by
69 * removing the commands from the issue queue and calling
70 * NCR5380_select() if a nexus is not established.
72 * Once a nexus is established, the NCR5380_information_transfer()
73 * phase goes through the various phases as instructed by the target.
74 * if the target goes into MSG IN and sends a DISCONNECT message,
75 * the command structure is placed into the per instance disconnected
76 * queue, and NCR5380_main tries to find more work. If the target is
77 * idle for too long, the system will try to sleep.
79 * If a command has disconnected, eventually an interrupt will trigger,
80 * calling NCR5380_intr() which will in turn call NCR5380_reselect
81 * to reestablish a nexus. This will run main if necessary.
83 * On command termination, the done function will be called as
86 * SCSI pointers are maintained in the SCp field of SCSI command
87 * structures, being initialized after the command is connected
88 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
89 * Note that in violation of the standard, an implicit SAVE POINTERS operation
90 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
95 * This file a skeleton Linux SCSI driver for the NCR 5380 series
96 * of chips. To use it, you write an architecture specific functions
97 * and macros and include this file in your driver.
99 * These macros control options :
100 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
101 * for commands that return with a CHECK CONDITION status.
103 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
106 * PSEUDO_DMA - if defined, PSEUDO DMA is used during the data transfer phases.
108 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
110 * These macros MUST be defined :
112 * NCR5380_read(register) - read from the specified register
114 * NCR5380_write(register, value) - write to the specific register
116 * NCR5380_implementation_fields - additional fields needed for this
117 * specific implementation of the NCR5380
119 * Either real DMA *or* pseudo DMA may be implemented
121 * NCR5380_dma_xfer_len - determine size of DMA/PDMA transfer
122 * NCR5380_dma_send_setup - execute DMA/PDMA from memory to 5380
123 * NCR5380_dma_recv_setup - execute DMA/PDMA from 5380 to memory
124 * NCR5380_dma_residual - residual byte count
126 * The generic driver is initialized by calling NCR5380_init(instance),
127 * after setting the appropriate host specific fields and ID.
130 #ifndef NCR5380_io_delay
131 #define NCR5380_io_delay(x)
134 #ifndef NCR5380_acquire_dma_irq
135 #define NCR5380_acquire_dma_irq(x) (1)
138 #ifndef NCR5380_release_dma_irq
139 #define NCR5380_release_dma_irq(x)
142 static int do_abort(struct Scsi_Host
*);
143 static void do_reset(struct Scsi_Host
*);
146 * initialize_SCp - init the scsi pointer field
147 * @cmd: command block to set up
149 * Set up the internal fields in the SCSI command.
152 static inline void initialize_SCp(struct scsi_cmnd
*cmd
)
155 * Initialize the Scsi Pointer field so that all of the commands in the
156 * various queues are valid.
159 if (scsi_bufflen(cmd
)) {
160 cmd
->SCp
.buffer
= scsi_sglist(cmd
);
161 cmd
->SCp
.buffers_residual
= scsi_sg_count(cmd
) - 1;
162 cmd
->SCp
.ptr
= sg_virt(cmd
->SCp
.buffer
);
163 cmd
->SCp
.this_residual
= cmd
->SCp
.buffer
->length
;
165 cmd
->SCp
.buffer
= NULL
;
166 cmd
->SCp
.buffers_residual
= 0;
168 cmd
->SCp
.this_residual
= 0;
172 cmd
->SCp
.Message
= 0;
176 * NCR5380_poll_politely2 - wait for two chip register values
177 * @hostdata: host private data
178 * @reg1: 5380 register to poll
179 * @bit1: Bitmask to check
180 * @val1: Expected value
181 * @reg2: Second 5380 register to poll
182 * @bit2: Second bitmask to check
183 * @val2: Second expected value
184 * @wait: Time-out in jiffies
186 * Polls the chip in a reasonably efficient manner waiting for an
187 * event to occur. After a short quick poll we begin to yield the CPU
188 * (if possible). In irq contexts the time-out is arbitrarily limited.
189 * Callers may hold locks as long as they are held in irq mode.
191 * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.
194 static int NCR5380_poll_politely2(struct NCR5380_hostdata
*hostdata
,
195 unsigned int reg1
, u8 bit1
, u8 val1
,
196 unsigned int reg2
, u8 bit2
, u8 val2
,
199 unsigned long n
= hostdata
->poll_loops
;
200 unsigned long deadline
= jiffies
+ wait
;
203 if ((NCR5380_read(reg1
) & bit1
) == val1
)
205 if ((NCR5380_read(reg2
) & bit2
) == val2
)
210 if (irqs_disabled() || in_interrupt())
213 /* Repeatedly sleep for 1 ms until deadline */
214 while (time_is_after_jiffies(deadline
)) {
215 schedule_timeout_uninterruptible(1);
216 if ((NCR5380_read(reg1
) & bit1
) == val1
)
218 if ((NCR5380_read(reg2
) & bit2
) == val2
)
241 {BASR_END_DMA_TRANSFER
, "END OF DMA"},
243 {BASR_PARITY_ERROR
, "PARITY ERROR"},
245 {BASR_PHASE_MATCH
, "PHASE MATCH"},
246 {BASR_BUSY_ERROR
, "BUSY ERROR"},
252 {ICR_ASSERT_RST
, "ASSERT RST"},
253 {ICR_ARBITRATION_PROGRESS
, "ARB. IN PROGRESS"},
254 {ICR_ARBITRATION_LOST
, "LOST ARB."},
255 {ICR_ASSERT_ACK
, "ASSERT ACK"},
256 {ICR_ASSERT_BSY
, "ASSERT BSY"},
257 {ICR_ASSERT_SEL
, "ASSERT SEL"},
258 {ICR_ASSERT_ATN
, "ASSERT ATN"},
259 {ICR_ASSERT_DATA
, "ASSERT DATA"},
263 {MR_BLOCK_DMA_MODE
, "BLOCK DMA MODE"},
264 {MR_TARGET
, "TARGET"},
265 {MR_ENABLE_PAR_CHECK
, "PARITY CHECK"},
266 {MR_ENABLE_PAR_INTR
, "PARITY INTR"},
267 {MR_ENABLE_EOP_INTR
, "EOP INTR"},
268 {MR_MONITOR_BSY
, "MONITOR BSY"},
269 {MR_DMA_MODE
, "DMA MODE"},
270 {MR_ARBITRATE
, "ARBITRATE"},
275 * NCR5380_print - print scsi bus signals
276 * @instance: adapter state to dump
278 * Print the SCSI bus signals for debugging purposes
281 static void NCR5380_print(struct Scsi_Host
*instance
)
283 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
284 unsigned char status
, data
, basr
, mr
, icr
, i
;
286 data
= NCR5380_read(CURRENT_SCSI_DATA_REG
);
287 status
= NCR5380_read(STATUS_REG
);
288 mr
= NCR5380_read(MODE_REG
);
289 icr
= NCR5380_read(INITIATOR_COMMAND_REG
);
290 basr
= NCR5380_read(BUS_AND_STATUS_REG
);
292 printk(KERN_DEBUG
"SR = 0x%02x : ", status
);
293 for (i
= 0; signals
[i
].mask
; ++i
)
294 if (status
& signals
[i
].mask
)
295 printk(KERN_CONT
"%s, ", signals
[i
].name
);
296 printk(KERN_CONT
"\nBASR = 0x%02x : ", basr
);
297 for (i
= 0; basrs
[i
].mask
; ++i
)
298 if (basr
& basrs
[i
].mask
)
299 printk(KERN_CONT
"%s, ", basrs
[i
].name
);
300 printk(KERN_CONT
"\nICR = 0x%02x : ", icr
);
301 for (i
= 0; icrs
[i
].mask
; ++i
)
302 if (icr
& icrs
[i
].mask
)
303 printk(KERN_CONT
"%s, ", icrs
[i
].name
);
304 printk(KERN_CONT
"\nMR = 0x%02x : ", mr
);
305 for (i
= 0; mrs
[i
].mask
; ++i
)
306 if (mr
& mrs
[i
].mask
)
307 printk(KERN_CONT
"%s, ", mrs
[i
].name
);
308 printk(KERN_CONT
"\n");
315 {PHASE_DATAOUT
, "DATAOUT"},
316 {PHASE_DATAIN
, "DATAIN"},
317 {PHASE_CMDOUT
, "CMDOUT"},
318 {PHASE_STATIN
, "STATIN"},
319 {PHASE_MSGOUT
, "MSGOUT"},
320 {PHASE_MSGIN
, "MSGIN"},
321 {PHASE_UNKNOWN
, "UNKNOWN"}
325 * NCR5380_print_phase - show SCSI phase
326 * @instance: adapter to dump
328 * Print the current SCSI phase for debugging purposes
331 static void NCR5380_print_phase(struct Scsi_Host
*instance
)
333 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
334 unsigned char status
;
337 status
= NCR5380_read(STATUS_REG
);
338 if (!(status
& SR_REQ
))
339 shost_printk(KERN_DEBUG
, instance
, "REQ not asserted, phase unknown.\n");
341 for (i
= 0; (phases
[i
].value
!= PHASE_UNKNOWN
) &&
342 (phases
[i
].value
!= (status
& PHASE_MASK
)); ++i
)
344 shost_printk(KERN_DEBUG
, instance
, "phase %s\n", phases
[i
].name
);
350 * NCR58380_info - report driver and host information
351 * @instance: relevant scsi host instance
353 * For use as the host template info() handler.
356 static const char *NCR5380_info(struct Scsi_Host
*instance
)
358 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
360 return hostdata
->info
;
363 static void prepare_info(struct Scsi_Host
*instance
)
365 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
367 snprintf(hostdata
->info
, sizeof(hostdata
->info
),
369 "io_port 0x%lx, base 0x%lx, "
370 "can_queue %d, cmd_per_lun %d, "
371 "sg_tablesize %d, this_id %d, "
374 instance
->hostt
->name
, instance
->irq
,
375 hostdata
->io_port
, hostdata
->base
,
376 instance
->can_queue
, instance
->cmd_per_lun
,
377 instance
->sg_tablesize
, instance
->this_id
,
378 hostdata
->flags
& FLAG_DMA_FIXUP
? "DMA_FIXUP " : "",
379 hostdata
->flags
& FLAG_NO_PSEUDO_DMA
? "NO_PSEUDO_DMA " : "",
380 hostdata
->flags
& FLAG_TOSHIBA_DELAY
? "TOSHIBA_DELAY " : "",
391 * NCR5380_init - initialise an NCR5380
392 * @instance: adapter to configure
393 * @flags: control flags
395 * Initializes *instance and corresponding 5380 chip,
396 * with flags OR'd into the initial flags value.
398 * Notes : I assume that the host, hostno, and id bits have been
399 * set correctly. I don't care about the irq and other fields.
401 * Returns 0 for success
404 static int NCR5380_init(struct Scsi_Host
*instance
, int flags
)
406 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
408 unsigned long deadline
;
409 unsigned long accesses_per_ms
;
411 instance
->max_lun
= 7;
413 hostdata
->host
= instance
;
414 hostdata
->id_mask
= 1 << instance
->this_id
;
415 hostdata
->id_higher_mask
= 0;
416 for (i
= hostdata
->id_mask
; i
<= 0x80; i
<<= 1)
417 if (i
> hostdata
->id_mask
)
418 hostdata
->id_higher_mask
|= i
;
419 for (i
= 0; i
< 8; ++i
)
420 hostdata
->busy
[i
] = 0;
421 hostdata
->dma_len
= 0;
423 spin_lock_init(&hostdata
->lock
);
424 hostdata
->connected
= NULL
;
425 hostdata
->sensing
= NULL
;
426 INIT_LIST_HEAD(&hostdata
->autosense
);
427 INIT_LIST_HEAD(&hostdata
->unissued
);
428 INIT_LIST_HEAD(&hostdata
->disconnected
);
430 hostdata
->flags
= flags
;
432 INIT_WORK(&hostdata
->main_task
, NCR5380_main
);
433 hostdata
->work_q
= alloc_workqueue("ncr5380_%d",
434 WQ_UNBOUND
| WQ_MEM_RECLAIM
,
435 1, instance
->host_no
);
436 if (!hostdata
->work_q
)
439 prepare_info(instance
);
441 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
442 NCR5380_write(MODE_REG
, MR_BASE
);
443 NCR5380_write(TARGET_COMMAND_REG
, 0);
444 NCR5380_write(SELECT_ENABLE_REG
, 0);
446 /* Calibrate register polling loop */
448 deadline
= jiffies
+ 1;
451 } while (time_is_after_jiffies(deadline
));
452 deadline
+= msecs_to_jiffies(256);
454 NCR5380_read(STATUS_REG
);
457 } while (time_is_after_jiffies(deadline
));
458 accesses_per_ms
= i
/ 256;
459 hostdata
->poll_loops
= NCR5380_REG_POLL_TIME
* accesses_per_ms
/ 2;
465 * NCR5380_maybe_reset_bus - Detect and correct bus wedge problems.
466 * @instance: adapter to check
468 * If the system crashed, it may have crashed with a connected target and
469 * the SCSI bus busy. Check for BUS FREE phase. If not, try to abort the
470 * currently established nexus, which we know nothing about. Failing that
473 * Note that a bus reset will cause the chip to assert IRQ.
475 * Returns 0 if successful, otherwise -ENXIO.
478 static int NCR5380_maybe_reset_bus(struct Scsi_Host
*instance
)
480 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
483 for (pass
= 1; (NCR5380_read(STATUS_REG
) & SR_BSY
) && pass
<= 6; ++pass
) {
488 shost_printk(KERN_ERR
, instance
, "SCSI bus busy, waiting up to five seconds\n");
489 NCR5380_poll_politely(hostdata
,
490 STATUS_REG
, SR_BSY
, 0, 5 * HZ
);
493 shost_printk(KERN_ERR
, instance
, "bus busy, attempting abort\n");
497 shost_printk(KERN_ERR
, instance
, "bus busy, attempting reset\n");
499 /* Wait after a reset; the SCSI standard calls for
500 * 250ms, we wait 500ms to be on the safe side.
501 * But some Toshiba CD-ROMs need ten times that.
503 if (hostdata
->flags
& FLAG_TOSHIBA_DELAY
)
509 shost_printk(KERN_ERR
, instance
, "bus locked solid\n");
517 * NCR5380_exit - remove an NCR5380
518 * @instance: adapter to remove
520 * Assumes that no more work can be queued (e.g. by NCR5380_intr).
523 static void NCR5380_exit(struct Scsi_Host
*instance
)
525 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
527 cancel_work_sync(&hostdata
->main_task
);
528 destroy_workqueue(hostdata
->work_q
);
532 * complete_cmd - finish processing a command and return it to the SCSI ML
533 * @instance: the host instance
534 * @cmd: command to complete
537 static void complete_cmd(struct Scsi_Host
*instance
,
538 struct scsi_cmnd
*cmd
)
540 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
542 dsprintk(NDEBUG_QUEUES
, instance
, "complete_cmd: cmd %p\n", cmd
);
544 if (hostdata
->sensing
== cmd
) {
545 /* Autosense processing ends here */
546 if ((cmd
->result
& 0xff) != SAM_STAT_GOOD
) {
547 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
548 set_host_byte(cmd
, DID_ERROR
);
550 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
551 hostdata
->sensing
= NULL
;
554 hostdata
->busy
[scmd_id(cmd
)] &= ~(1 << cmd
->device
->lun
);
560 * NCR5380_queue_command - queue a command
561 * @instance: the relevant SCSI adapter
564 * cmd is added to the per-instance issue queue, with minor
565 * twiddling done to the host specific fields of cmd. If the
566 * main coroutine is not running, it is restarted.
569 static int NCR5380_queue_command(struct Scsi_Host
*instance
,
570 struct scsi_cmnd
*cmd
)
572 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
573 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
576 #if (NDEBUG & NDEBUG_NO_WRITE)
577 switch (cmd
->cmnd
[0]) {
580 shost_printk(KERN_DEBUG
, instance
, "WRITE attempted with NDEBUG_NO_WRITE set\n");
581 cmd
->result
= (DID_ERROR
<< 16);
585 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
589 if (!NCR5380_acquire_dma_irq(instance
))
590 return SCSI_MLQUEUE_HOST_BUSY
;
592 spin_lock_irqsave(&hostdata
->lock
, flags
);
595 * Insert the cmd into the issue queue. Note that REQUEST SENSE
596 * commands are added to the head of the queue since any command will
597 * clear the contingent allegiance condition that exists and the
598 * sense data is only guaranteed to be valid while the condition exists.
601 if (cmd
->cmnd
[0] == REQUEST_SENSE
)
602 list_add(&ncmd
->list
, &hostdata
->unissued
);
604 list_add_tail(&ncmd
->list
, &hostdata
->unissued
);
606 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
608 dsprintk(NDEBUG_QUEUES
, instance
, "command %p added to %s of queue\n",
609 cmd
, (cmd
->cmnd
[0] == REQUEST_SENSE
) ? "head" : "tail");
611 /* Kick off command processing */
612 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
616 static inline void maybe_release_dma_irq(struct Scsi_Host
*instance
)
618 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
620 /* Caller does the locking needed to set & test these data atomically */
621 if (list_empty(&hostdata
->disconnected
) &&
622 list_empty(&hostdata
->unissued
) &&
623 list_empty(&hostdata
->autosense
) &&
624 !hostdata
->connected
&&
625 !hostdata
->selecting
)
626 NCR5380_release_dma_irq(instance
);
630 * dequeue_next_cmd - dequeue a command for processing
631 * @instance: the scsi host instance
633 * Priority is given to commands on the autosense queue. These commands
634 * need autosense because of a CHECK CONDITION result.
636 * Returns a command pointer if a command is found for a target that is
637 * not already busy. Otherwise returns NULL.
640 static struct scsi_cmnd
*dequeue_next_cmd(struct Scsi_Host
*instance
)
642 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
643 struct NCR5380_cmd
*ncmd
;
644 struct scsi_cmnd
*cmd
;
646 if (hostdata
->sensing
|| list_empty(&hostdata
->autosense
)) {
647 list_for_each_entry(ncmd
, &hostdata
->unissued
, list
) {
648 cmd
= NCR5380_to_scmd(ncmd
);
649 dsprintk(NDEBUG_QUEUES
, instance
, "dequeue: cmd=%p target=%d busy=0x%02x lun=%llu\n",
650 cmd
, scmd_id(cmd
), hostdata
->busy
[scmd_id(cmd
)], cmd
->device
->lun
);
652 if (!(hostdata
->busy
[scmd_id(cmd
)] & (1 << cmd
->device
->lun
))) {
653 list_del(&ncmd
->list
);
654 dsprintk(NDEBUG_QUEUES
, instance
,
655 "dequeue: removed %p from issue queue\n", cmd
);
660 /* Autosense processing begins here */
661 ncmd
= list_first_entry(&hostdata
->autosense
,
662 struct NCR5380_cmd
, list
);
663 list_del(&ncmd
->list
);
664 cmd
= NCR5380_to_scmd(ncmd
);
665 dsprintk(NDEBUG_QUEUES
, instance
,
666 "dequeue: removed %p from autosense queue\n", cmd
);
667 scsi_eh_prep_cmnd(cmd
, &hostdata
->ses
, NULL
, 0, ~0);
668 hostdata
->sensing
= cmd
;
674 static void requeue_cmd(struct Scsi_Host
*instance
, struct scsi_cmnd
*cmd
)
676 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
677 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
679 if (hostdata
->sensing
== cmd
) {
680 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
681 list_add(&ncmd
->list
, &hostdata
->autosense
);
682 hostdata
->sensing
= NULL
;
684 list_add(&ncmd
->list
, &hostdata
->unissued
);
688 * NCR5380_main - NCR state machines
690 * NCR5380_main is a coroutine that runs as long as more work can
691 * be done on the NCR5380 host adapters in a system. Both
692 * NCR5380_queue_command() and NCR5380_intr() will try to start it
693 * in case it is not running.
696 static void NCR5380_main(struct work_struct
*work
)
698 struct NCR5380_hostdata
*hostdata
=
699 container_of(work
, struct NCR5380_hostdata
, main_task
);
700 struct Scsi_Host
*instance
= hostdata
->host
;
706 spin_lock_irq(&hostdata
->lock
);
707 while (!hostdata
->connected
&& !hostdata
->selecting
) {
708 struct scsi_cmnd
*cmd
= dequeue_next_cmd(instance
);
713 dsprintk(NDEBUG_MAIN
, instance
, "main: dequeued %p\n", cmd
);
716 * Attempt to establish an I_T_L nexus here.
717 * On success, instance->hostdata->connected is set.
718 * On failure, we must add the command back to the
719 * issue queue so we can keep trying.
722 * REQUEST SENSE commands are issued without tagged
723 * queueing, even on SCSI-II devices because the
724 * contingent allegiance condition exists for the
728 if (!NCR5380_select(instance
, cmd
)) {
729 dsprintk(NDEBUG_MAIN
, instance
, "main: select complete\n");
730 maybe_release_dma_irq(instance
);
732 dsprintk(NDEBUG_MAIN
| NDEBUG_QUEUES
, instance
,
733 "main: select failed, returning %p to queue\n", cmd
);
734 requeue_cmd(instance
, cmd
);
737 if (hostdata
->connected
&& !hostdata
->dma_len
) {
738 dsprintk(NDEBUG_MAIN
, instance
, "main: performing information transfer\n");
739 NCR5380_information_transfer(instance
);
742 spin_unlock_irq(&hostdata
->lock
);
749 * NCR5380_dma_complete - finish DMA transfer
750 * @instance: the scsi host instance
752 * Called by the interrupt handler when DMA finishes or a phase
753 * mismatch occurs (which would end the DMA transfer).
756 static void NCR5380_dma_complete(struct Scsi_Host
*instance
)
758 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
760 unsigned char **data
;
762 int saved_data
= 0, overrun
= 0;
765 if (hostdata
->read_overruns
) {
766 p
= hostdata
->connected
->SCp
.phase
;
769 if ((NCR5380_read(BUS_AND_STATUS_REG
) &
770 (BASR_PHASE_MATCH
| BASR_ACK
)) ==
771 (BASR_PHASE_MATCH
| BASR_ACK
)) {
772 saved_data
= NCR5380_read(INPUT_DATA_REG
);
774 dsprintk(NDEBUG_DMA
, instance
, "read overrun handled\n");
780 if ((sun3scsi_dma_finish(rq_data_dir(hostdata
->connected
->request
)))) {
781 pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n",
786 if ((NCR5380_read(BUS_AND_STATUS_REG
) & (BASR_PHASE_MATCH
| BASR_ACK
)) ==
787 (BASR_PHASE_MATCH
| BASR_ACK
)) {
788 pr_err("scsi%d: BASR %02x\n", instance
->host_no
,
789 NCR5380_read(BUS_AND_STATUS_REG
));
790 pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n",
796 NCR5380_write(MODE_REG
, MR_BASE
);
797 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
798 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
800 transferred
= hostdata
->dma_len
- NCR5380_dma_residual(hostdata
);
801 hostdata
->dma_len
= 0;
803 data
= (unsigned char **)&hostdata
->connected
->SCp
.ptr
;
804 count
= &hostdata
->connected
->SCp
.this_residual
;
805 *data
+= transferred
;
806 *count
-= transferred
;
808 if (hostdata
->read_overruns
) {
811 if ((NCR5380_read(STATUS_REG
) & PHASE_MASK
) == p
&& (p
& SR_IO
)) {
812 cnt
= toPIO
= hostdata
->read_overruns
;
814 dsprintk(NDEBUG_DMA
, instance
,
815 "Got an input overrun, using saved byte\n");
816 *(*data
)++ = saved_data
;
822 dsprintk(NDEBUG_DMA
, instance
,
823 "Doing %d byte PIO to 0x%p\n", cnt
, *data
);
824 NCR5380_transfer_pio(instance
, &p
, &cnt
, data
);
825 *count
-= toPIO
- cnt
;
832 * NCR5380_intr - generic NCR5380 irq handler
833 * @irq: interrupt number
834 * @dev_id: device info
836 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
837 * from the disconnected queue, and restarting NCR5380_main()
840 * The chip can assert IRQ in any of six different conditions. The IRQ flag
841 * is then cleared by reading the Reset Parity/Interrupt Register (RPIR).
842 * Three of these six conditions are latched in the Bus and Status Register:
843 * - End of DMA (cleared by ending DMA Mode)
844 * - Parity error (cleared by reading RPIR)
845 * - Loss of BSY (cleared by reading RPIR)
846 * Two conditions have flag bits that are not latched:
847 * - Bus phase mismatch (non-maskable in DMA Mode, cleared by ending DMA Mode)
848 * - Bus reset (non-maskable)
849 * The remaining condition has no flag bit at all:
850 * - Selection/reselection
852 * Hence, establishing the cause(s) of any interrupt is partly guesswork.
853 * In "The DP8490 and DP5380 Comparison Guide", National Semiconductor
854 * claimed that "the design of the [DP8490] interrupt logic ensures
855 * interrupts will not be lost (they can be on the DP5380)."
856 * The L5380/53C80 datasheet from LOGIC Devices has more details.
858 * Checking for bus reset by reading RST is futile because of interrupt
859 * latency, but a bus reset will reset chip logic. Checking for parity error
860 * is unnecessary because that interrupt is never enabled. A Loss of BSY
861 * condition will clear DMA Mode. We can tell when this occurs because the
862 * the Busy Monitor interrupt is enabled together with DMA Mode.
865 static irqreturn_t __maybe_unused
NCR5380_intr(int irq
, void *dev_id
)
867 struct Scsi_Host
*instance
= dev_id
;
868 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
873 spin_lock_irqsave(&hostdata
->lock
, flags
);
875 basr
= NCR5380_read(BUS_AND_STATUS_REG
);
876 if (basr
& BASR_IRQ
) {
877 unsigned char mr
= NCR5380_read(MODE_REG
);
878 unsigned char sr
= NCR5380_read(STATUS_REG
);
880 dsprintk(NDEBUG_INTR
, instance
, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n",
883 if ((mr
& MR_DMA_MODE
) || (mr
& MR_MONITOR_BSY
)) {
884 /* Probably End of DMA, Phase Mismatch or Loss of BSY.
885 * We ack IRQ after clearing Mode Register. Workarounds
886 * for End of DMA errata need to happen in DMA Mode.
889 dsprintk(NDEBUG_INTR
, instance
, "interrupt in DMA mode\n");
891 if (hostdata
->connected
) {
892 NCR5380_dma_complete(instance
);
893 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
895 NCR5380_write(MODE_REG
, MR_BASE
);
896 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
898 } else if ((NCR5380_read(CURRENT_SCSI_DATA_REG
) & hostdata
->id_mask
) &&
899 (sr
& (SR_SEL
| SR_IO
| SR_BSY
| SR_RST
)) == (SR_SEL
| SR_IO
)) {
900 /* Probably reselected */
901 NCR5380_write(SELECT_ENABLE_REG
, 0);
902 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
904 dsprintk(NDEBUG_INTR
, instance
, "interrupt with SEL and IO\n");
906 if (!hostdata
->connected
) {
907 NCR5380_reselect(instance
);
908 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
910 if (!hostdata
->connected
)
911 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
913 /* Probably Bus Reset */
914 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
916 dsprintk(NDEBUG_INTR
, instance
, "unknown interrupt\n");
918 dregs
->csr
|= CSR_DMA_ENABLE
;
923 dsprintk(NDEBUG_INTR
, instance
, "interrupt without IRQ bit\n");
925 dregs
->csr
|= CSR_DMA_ENABLE
;
929 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
931 return IRQ_RETVAL(handled
);
935 * Function : int NCR5380_select(struct Scsi_Host *instance,
936 * struct scsi_cmnd *cmd)
938 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
939 * including ARBITRATION, SELECTION, and initial message out for
940 * IDENTIFY and queue messages.
942 * Inputs : instance - instantiation of the 5380 driver on which this
943 * target lives, cmd - SCSI command to execute.
945 * Returns cmd if selection failed but should be retried,
946 * NULL if selection failed and should not be retried, or
947 * NULL if selection succeeded (hostdata->connected == cmd).
950 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
951 * with registers as they should have been on entry - ie
952 * SELECT_ENABLE will be set appropriately, the NCR5380
953 * will cease to drive any SCSI bus signals.
955 * If successful : I_T_L or I_T_L_Q nexus will be established,
956 * instance->connected will be set to cmd.
957 * SELECT interrupt will be disabled.
959 * If failed (no target) : cmd->scsi_done() will be called, and the
960 * cmd->result host byte set to DID_BAD_TARGET.
963 static struct scsi_cmnd
*NCR5380_select(struct Scsi_Host
*instance
,
964 struct scsi_cmnd
*cmd
)
966 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
967 unsigned char tmp
[3], phase
;
972 NCR5380_dprint(NDEBUG_ARBITRATION
, instance
);
973 dsprintk(NDEBUG_ARBITRATION
, instance
, "starting arbitration, id = %d\n",
977 * Arbitration and selection phases are slow and involve dropping the
978 * lock, so we have to watch out for EH. An exception handler may
979 * change 'selecting' to NULL. This function will then return NULL
980 * so that the caller will forget about 'cmd'. (During information
981 * transfer phases, EH may change 'connected' to NULL.)
983 hostdata
->selecting
= cmd
;
986 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
987 * data bus during SELECTION.
990 NCR5380_write(TARGET_COMMAND_REG
, 0);
996 NCR5380_write(OUTPUT_DATA_REG
, hostdata
->id_mask
);
997 NCR5380_write(MODE_REG
, MR_ARBITRATE
);
999 /* The chip now waits for BUS FREE phase. Then after the 800 ns
1000 * Bus Free Delay, arbitration will begin.
1003 spin_unlock_irq(&hostdata
->lock
);
1004 err
= NCR5380_poll_politely2(hostdata
, MODE_REG
, MR_ARBITRATE
, 0,
1005 INITIATOR_COMMAND_REG
, ICR_ARBITRATION_PROGRESS
,
1006 ICR_ARBITRATION_PROGRESS
, HZ
);
1007 spin_lock_irq(&hostdata
->lock
);
1008 if (!(NCR5380_read(MODE_REG
) & MR_ARBITRATE
)) {
1009 /* Reselection interrupt */
1012 if (!hostdata
->selecting
) {
1013 /* Command was aborted */
1014 NCR5380_write(MODE_REG
, MR_BASE
);
1018 NCR5380_write(MODE_REG
, MR_BASE
);
1019 shost_printk(KERN_ERR
, instance
,
1020 "select: arbitration timeout\n");
1023 spin_unlock_irq(&hostdata
->lock
);
1025 /* The SCSI-2 arbitration delay is 2.4 us */
1028 /* Check for lost arbitration */
1029 if ((NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_LOST
) ||
1030 (NCR5380_read(CURRENT_SCSI_DATA_REG
) & hostdata
->id_higher_mask
) ||
1031 (NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_LOST
)) {
1032 NCR5380_write(MODE_REG
, MR_BASE
);
1033 dsprintk(NDEBUG_ARBITRATION
, instance
, "lost arbitration, deasserting MR_ARBITRATE\n");
1034 spin_lock_irq(&hostdata
->lock
);
1038 /* After/during arbitration, BSY should be asserted.
1039 * IBM DPES-31080 Version S31Q works now
1040 * Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman)
1042 NCR5380_write(INITIATOR_COMMAND_REG
,
1043 ICR_BASE
| ICR_ASSERT_SEL
| ICR_ASSERT_BSY
);
1046 * Again, bus clear + bus settle time is 1.2us, however, this is
1047 * a minimum so we'll udelay ceil(1.2)
1050 if (hostdata
->flags
& FLAG_TOSHIBA_DELAY
)
1055 spin_lock_irq(&hostdata
->lock
);
1057 /* NCR5380_reselect() clears MODE_REG after a reselection interrupt */
1058 if (!(NCR5380_read(MODE_REG
) & MR_ARBITRATE
))
1061 if (!hostdata
->selecting
) {
1062 NCR5380_write(MODE_REG
, MR_BASE
);
1063 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1067 dsprintk(NDEBUG_ARBITRATION
, instance
, "won arbitration\n");
1070 * Now that we have won arbitration, start Selection process, asserting
1071 * the host and target ID's on the SCSI bus.
1074 NCR5380_write(OUTPUT_DATA_REG
, hostdata
->id_mask
| (1 << scmd_id(cmd
)));
1077 * Raise ATN while SEL is true before BSY goes false from arbitration,
1078 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1079 * phase immediately after selection.
1082 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_BSY
|
1083 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
| ICR_ASSERT_SEL
);
1084 NCR5380_write(MODE_REG
, MR_BASE
);
1087 * Reselect interrupts must be turned off prior to the dropping of BSY,
1088 * otherwise we will trigger an interrupt.
1090 NCR5380_write(SELECT_ENABLE_REG
, 0);
1092 spin_unlock_irq(&hostdata
->lock
);
1095 * The initiator shall then wait at least two deskew delays and release
1098 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1101 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
|
1102 ICR_ASSERT_ATN
| ICR_ASSERT_SEL
);
1105 * Something weird happens when we cease to drive BSY - looks
1106 * like the board/chip is letting us do another read before the
1107 * appropriate propagation delay has expired, and we're confusing
1108 * a BSY signal from ourselves as the target's response to SELECTION.
1110 * A small delay (the 'C++' frontend breaks the pipeline with an
1111 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1112 * tighter 'C' code breaks and requires this) solves the problem -
1113 * the 1 us delay is arbitrary, and only used because this delay will
1114 * be the same on other platforms and since it works here, it should
1117 * wingel suggests that this could be due to failing to wait
1123 dsprintk(NDEBUG_SELECTION
, instance
, "selecting target %d\n", scmd_id(cmd
));
1126 * The SCSI specification calls for a 250 ms timeout for the actual
1130 err
= NCR5380_poll_politely(hostdata
, STATUS_REG
, SR_BSY
, SR_BSY
,
1131 msecs_to_jiffies(250));
1133 if ((NCR5380_read(STATUS_REG
) & (SR_SEL
| SR_IO
)) == (SR_SEL
| SR_IO
)) {
1134 spin_lock_irq(&hostdata
->lock
);
1135 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1136 NCR5380_reselect(instance
);
1137 if (!hostdata
->connected
)
1138 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1139 shost_printk(KERN_ERR
, instance
, "reselection after won arbitration?\n");
1144 spin_lock_irq(&hostdata
->lock
);
1145 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1146 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1147 /* Can't touch cmd if it has been reclaimed by the scsi ML */
1148 if (hostdata
->selecting
) {
1149 cmd
->result
= DID_BAD_TARGET
<< 16;
1150 complete_cmd(instance
, cmd
);
1151 dsprintk(NDEBUG_SELECTION
, instance
, "target did not respond within 250ms\n");
1158 * No less than two deskew delays after the initiator detects the
1159 * BSY signal is true, it shall release the SEL signal and may
1160 * change the DATA BUS. -wingel
1165 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1168 * Since we followed the SCSI spec, and raised ATN while SEL
1169 * was true but before BSY was false during selection, the information
1170 * transfer phase should be a MESSAGE OUT phase so that we can send the
1174 /* Wait for start of REQ/ACK handshake */
1176 err
= NCR5380_poll_politely(hostdata
, STATUS_REG
, SR_REQ
, SR_REQ
, HZ
);
1177 spin_lock_irq(&hostdata
->lock
);
1179 shost_printk(KERN_ERR
, instance
, "select: REQ timeout\n");
1180 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1181 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1184 if (!hostdata
->selecting
) {
1189 dsprintk(NDEBUG_SELECTION
, instance
, "target %d selected, going into MESSAGE OUT phase.\n",
1191 tmp
[0] = IDENTIFY(((instance
->irq
== NO_IRQ
) ? 0 : 1), cmd
->device
->lun
);
1195 phase
= PHASE_MSGOUT
;
1196 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
1197 dsprintk(NDEBUG_SELECTION
, instance
, "nexus established.\n");
1198 /* XXX need to handle errors here */
1200 hostdata
->connected
= cmd
;
1201 hostdata
->busy
[cmd
->device
->id
] |= 1 << cmd
->device
->lun
;
1203 #ifdef SUN3_SCSI_VME
1204 dregs
->csr
|= CSR_INTR
;
1207 initialize_SCp(cmd
);
1212 if (!hostdata
->selecting
)
1214 hostdata
->selecting
= NULL
;
1219 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1220 * unsigned char *phase, int *count, unsigned char **data)
1222 * Purpose : transfers data in given phase using polled I/O
1224 * Inputs : instance - instance of driver, *phase - pointer to
1225 * what phase is expected, *count - pointer to number of
1226 * bytes to transfer, **data - pointer to data pointer.
1228 * Returns : -1 when different phase is entered without transferring
1229 * maximum number of bytes, 0 if all bytes are transferred or exit
1232 * Also, *phase, *count, *data are modified in place.
1234 * XXX Note : handling for bus free may be useful.
1238 * Note : this code is not as quick as it could be, however it
1239 * IS 100% reliable, and for the actual data transfer where speed
1240 * counts, we will always do a pseudo DMA or DMA transfer.
1243 static int NCR5380_transfer_pio(struct Scsi_Host
*instance
,
1244 unsigned char *phase
, int *count
,
1245 unsigned char **data
)
1247 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1248 unsigned char p
= *phase
, tmp
;
1250 unsigned char *d
= *data
;
1253 * The NCR5380 chip will only drive the SCSI bus when the
1254 * phase specified in the appropriate bits of the TARGET COMMAND
1255 * REGISTER match the STATUS REGISTER
1258 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1262 * Wait for assertion of REQ, after which the phase bits will be
1266 if (NCR5380_poll_politely(hostdata
, STATUS_REG
, SR_REQ
, SR_REQ
, HZ
) < 0)
1269 dsprintk(NDEBUG_HANDSHAKE
, instance
, "REQ asserted\n");
1271 /* Check for phase mismatch */
1272 if ((NCR5380_read(STATUS_REG
) & PHASE_MASK
) != p
) {
1273 dsprintk(NDEBUG_PIO
, instance
, "phase mismatch\n");
1274 NCR5380_dprint_phase(NDEBUG_PIO
, instance
);
1278 /* Do actual transfer from SCSI bus to / from memory */
1280 NCR5380_write(OUTPUT_DATA_REG
, *d
);
1282 *d
= NCR5380_read(CURRENT_SCSI_DATA_REG
);
1287 * The SCSI standard suggests that in MSGOUT phase, the initiator
1288 * should drop ATN on the last byte of the message phase
1289 * after REQ has been asserted for the handshake but before
1290 * the initiator raises ACK.
1294 if (!((p
& SR_MSG
) && c
> 1)) {
1295 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
);
1296 NCR5380_dprint(NDEBUG_PIO
, instance
);
1297 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1298 ICR_ASSERT_DATA
| ICR_ASSERT_ACK
);
1300 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1301 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
);
1302 NCR5380_dprint(NDEBUG_PIO
, instance
);
1303 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1304 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
| ICR_ASSERT_ACK
);
1307 NCR5380_dprint(NDEBUG_PIO
, instance
);
1308 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ACK
);
1311 if (NCR5380_poll_politely(hostdata
,
1312 STATUS_REG
, SR_REQ
, 0, 5 * HZ
) < 0)
1315 dsprintk(NDEBUG_HANDSHAKE
, instance
, "REQ negated, handshake complete\n");
1318 * We have several special cases to consider during REQ/ACK handshaking :
1319 * 1. We were in MSGOUT phase, and we are on the last byte of the
1320 * message. ATN must be dropped as ACK is dropped.
1322 * 2. We are in a MSGIN phase, and we are on the last byte of the
1323 * message. We must exit with ACK asserted, so that the calling
1324 * code may raise ATN before dropping ACK to reject the message.
1326 * 3. ACK and ATN are clear and the target may proceed as normal.
1328 if (!(p
== PHASE_MSGIN
&& c
== 1)) {
1329 if (p
== PHASE_MSGOUT
&& c
> 1)
1330 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1332 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1336 dsprintk(NDEBUG_PIO
, instance
, "residual %d\n", c
);
1340 tmp
= NCR5380_read(STATUS_REG
);
1341 /* The phase read from the bus is valid if either REQ is (already)
1342 * asserted or if ACK hasn't been released yet. The latter applies if
1343 * we're in MSG IN, DATA IN or STATUS and all bytes have been received.
1345 if ((tmp
& SR_REQ
) || ((tmp
& SR_IO
) && c
== 0))
1346 *phase
= tmp
& PHASE_MASK
;
1348 *phase
= PHASE_UNKNOWN
;
1350 if (!c
|| (*phase
== p
))
1357 * do_reset - issue a reset command
1358 * @instance: adapter to reset
1360 * Issue a reset sequence to the NCR5380 and try and get the bus
1361 * back into sane shape.
1363 * This clears the reset interrupt flag because there may be no handler for
1364 * it. When the driver is initialized, the NCR5380_intr() handler has not yet
1365 * been installed. And when in EH we may have released the ST DMA interrupt.
1368 static void do_reset(struct Scsi_Host
*instance
)
1370 struct NCR5380_hostdata __maybe_unused
*hostdata
= shost_priv(instance
);
1371 unsigned long flags
;
1373 local_irq_save(flags
);
1374 NCR5380_write(TARGET_COMMAND_REG
,
1375 PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG
) & PHASE_MASK
));
1376 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_RST
);
1378 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1379 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1380 local_irq_restore(flags
);
1384 * do_abort - abort the currently established nexus by going to
1385 * MESSAGE OUT phase and sending an ABORT message.
1386 * @instance: relevant scsi host instance
1388 * Returns 0 on success, -1 on failure.
1391 static int do_abort(struct Scsi_Host
*instance
)
1393 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1394 unsigned char *msgptr
, phase
, tmp
;
1398 /* Request message out phase */
1399 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1402 * Wait for the target to indicate a valid phase by asserting
1403 * REQ. Once this happens, we'll have either a MSGOUT phase
1404 * and can immediately send the ABORT message, or we'll have some
1405 * other phase and will have to source/sink data.
1407 * We really don't care what value was on the bus or what value
1408 * the target sees, so we just handshake.
1411 rc
= NCR5380_poll_politely(hostdata
, STATUS_REG
, SR_REQ
, SR_REQ
, 10 * HZ
);
1415 tmp
= NCR5380_read(STATUS_REG
) & PHASE_MASK
;
1417 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(tmp
));
1419 if (tmp
!= PHASE_MSGOUT
) {
1420 NCR5380_write(INITIATOR_COMMAND_REG
,
1421 ICR_BASE
| ICR_ASSERT_ATN
| ICR_ASSERT_ACK
);
1422 rc
= NCR5380_poll_politely(hostdata
, STATUS_REG
, SR_REQ
, 0, 3 * HZ
);
1425 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1431 phase
= PHASE_MSGOUT
;
1432 NCR5380_transfer_pio(instance
, &phase
, &len
, &msgptr
);
1435 * If we got here, and the command completed successfully,
1436 * we're about to go into bus free state.
1439 return len
? -1 : 0;
1442 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1447 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1448 * unsigned char *phase, int *count, unsigned char **data)
1450 * Purpose : transfers data in given phase using either real
1453 * Inputs : instance - instance of driver, *phase - pointer to
1454 * what phase is expected, *count - pointer to number of
1455 * bytes to transfer, **data - pointer to data pointer.
1457 * Returns : -1 when different phase is entered without transferring
1458 * maximum number of bytes, 0 if all bytes or transferred or exit
1461 * Also, *phase, *count, *data are modified in place.
1465 static int NCR5380_transfer_dma(struct Scsi_Host
*instance
,
1466 unsigned char *phase
, int *count
,
1467 unsigned char **data
)
1469 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1471 unsigned char p
= *phase
;
1472 unsigned char *d
= *data
;
1476 if ((tmp
= (NCR5380_read(STATUS_REG
) & PHASE_MASK
)) != p
) {
1481 hostdata
->connected
->SCp
.phase
= p
;
1484 if (hostdata
->read_overruns
)
1485 c
-= hostdata
->read_overruns
;
1486 else if (hostdata
->flags
& FLAG_DMA_FIXUP
)
1490 dsprintk(NDEBUG_DMA
, instance
, "initializing DMA %s: length %d, address %p\n",
1491 (p
& SR_IO
) ? "receive" : "send", c
, d
);
1494 /* send start chain */
1495 sun3scsi_dma_start(c
, *data
);
1498 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1499 NCR5380_write(MODE_REG
, MR_BASE
| MR_DMA_MODE
| MR_MONITOR_BSY
|
1500 MR_ENABLE_EOP_INTR
);
1502 if (!(hostdata
->flags
& FLAG_LATE_DMA_SETUP
)) {
1503 /* On the Medusa, it is a must to initialize the DMA before
1504 * starting the NCR. This is also the cleaner way for the TT.
1507 result
= NCR5380_dma_recv_setup(hostdata
, d
, c
);
1509 result
= NCR5380_dma_send_setup(hostdata
, d
, c
);
1513 * On the PAS16 at least I/O recovery delays are not needed here.
1514 * Everyone else seems to want them.
1518 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1519 NCR5380_io_delay(1);
1520 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG
, 0);
1522 NCR5380_io_delay(1);
1523 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
);
1524 NCR5380_io_delay(1);
1525 NCR5380_write(START_DMA_SEND_REG
, 0);
1526 NCR5380_io_delay(1);
1530 #ifdef SUN3_SCSI_VME
1531 dregs
->csr
|= CSR_DMA_ENABLE
;
1533 sun3_dma_active
= 1;
1536 if (hostdata
->flags
& FLAG_LATE_DMA_SETUP
) {
1537 /* On the Falcon, the DMA setup must be done after the last
1538 * NCR access, else the DMA setup gets trashed!
1541 result
= NCR5380_dma_recv_setup(hostdata
, d
, c
);
1543 result
= NCR5380_dma_send_setup(hostdata
, d
, c
);
1546 /* On failure, NCR5380_dma_xxxx_setup() returns a negative int. */
1550 /* For real DMA, result is the byte count. DMA interrupt is expected. */
1552 hostdata
->dma_len
= result
;
1556 /* The result is zero iff pseudo DMA send/receive was completed. */
1557 hostdata
->dma_len
= c
;
1560 * A note regarding the DMA errata workarounds for early NMOS silicon.
1562 * For DMA sends, we want to wait until the last byte has been
1563 * transferred out over the bus before we turn off DMA mode. Alas, there
1564 * seems to be no terribly good way of doing this on a 5380 under all
1565 * conditions. For non-scatter-gather operations, we can wait until REQ
1566 * and ACK both go false, or until a phase mismatch occurs. Gather-sends
1567 * are nastier, since the device will be expecting more data than we
1568 * are prepared to send it, and REQ will remain asserted. On a 53C8[01] we
1569 * could test Last Byte Sent to assure transfer (I imagine this is precisely
1570 * why this signal was added to the newer chips) but on the older 538[01]
1571 * this signal does not exist. The workaround for this lack is a watchdog;
1572 * we bail out of the wait-loop after a modest amount of wait-time if
1573 * the usual exit conditions are not met. Not a terribly clean or
1574 * correct solution :-%
1576 * DMA receive is equally tricky due to a nasty characteristic of the NCR5380.
1577 * If the chip is in DMA receive mode, it will respond to a target's
1578 * REQ by latching the SCSI data into the INPUT DATA register and asserting
1579 * ACK, even if it has _already_ been notified by the DMA controller that
1580 * the current DMA transfer has completed! If the NCR5380 is then taken
1581 * out of DMA mode, this already-acknowledged byte is lost. This is
1582 * not a problem for "one DMA transfer per READ command", because
1583 * the situation will never arise... either all of the data is DMA'ed
1584 * properly, or the target switches to MESSAGE IN phase to signal a
1585 * disconnection (either operation bringing the DMA to a clean halt).
1586 * However, in order to handle scatter-receive, we must work around the
1587 * problem. The chosen fix is to DMA fewer bytes, then check for the
1588 * condition before taking the NCR5380 out of DMA mode. One or two extra
1589 * bytes are transferred via PIO as necessary to fill out the original
1593 if (hostdata
->flags
& FLAG_DMA_FIXUP
) {
1596 * The workaround was to transfer fewer bytes than we
1597 * intended to with the pseudo-DMA read function, wait for
1598 * the chip to latch the last byte, read it, and then disable
1601 * After REQ is asserted, the NCR5380 asserts DRQ and ACK.
1602 * REQ is deasserted when ACK is asserted, and not reasserted
1603 * until ACK goes false. Since the NCR5380 won't lower ACK
1604 * until DACK is asserted, which won't happen unless we twiddle
1605 * the DMA port or we take the NCR5380 out of DMA mode, we
1606 * can guarantee that we won't handshake another extra
1610 if (NCR5380_poll_politely(hostdata
, BUS_AND_STATUS_REG
,
1611 BASR_DRQ
, BASR_DRQ
, HZ
) < 0) {
1613 shost_printk(KERN_ERR
, instance
, "PDMA read: DRQ timeout\n");
1615 if (NCR5380_poll_politely(hostdata
, STATUS_REG
,
1616 SR_REQ
, 0, HZ
) < 0) {
1618 shost_printk(KERN_ERR
, instance
, "PDMA read: !REQ timeout\n");
1620 d
[*count
- 1] = NCR5380_read(INPUT_DATA_REG
);
1623 * Wait for the last byte to be sent. If REQ is being asserted for
1624 * the byte we're interested, we'll ACK it and it will go false.
1626 if (NCR5380_poll_politely2(hostdata
,
1627 BUS_AND_STATUS_REG
, BASR_DRQ
, BASR_DRQ
,
1628 BUS_AND_STATUS_REG
, BASR_PHASE_MATCH
, 0, HZ
) < 0) {
1630 shost_printk(KERN_ERR
, instance
, "PDMA write: DRQ and phase timeout\n");
1635 NCR5380_dma_complete(instance
);
1640 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1642 * Purpose : run through the various SCSI phases and do as the target
1643 * directs us to. Operates on the currently connected command,
1644 * instance->connected.
1646 * Inputs : instance, instance for which we are doing commands
1648 * Side effects : SCSI things happen, the disconnected queue will be
1649 * modified if a command disconnects, *instance->connected will
1652 * XXX Note : we need to watch for bus free or a reset condition here
1653 * to recover from an unexpected bus free condition.
1656 static void NCR5380_information_transfer(struct Scsi_Host
*instance
)
1658 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1659 unsigned char msgout
= NOP
;
1663 unsigned char *data
;
1664 unsigned char phase
, tmp
, extended_msg
[10], old_phase
= 0xff;
1665 struct scsi_cmnd
*cmd
;
1667 #ifdef SUN3_SCSI_VME
1668 dregs
->csr
|= CSR_INTR
;
1671 while ((cmd
= hostdata
->connected
)) {
1672 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
1674 tmp
= NCR5380_read(STATUS_REG
);
1675 /* We only have a valid SCSI phase when REQ is asserted */
1677 phase
= (tmp
& PHASE_MASK
);
1678 if (phase
!= old_phase
) {
1680 NCR5380_dprint_phase(NDEBUG_INFORMATION
, instance
);
1683 if (phase
== PHASE_CMDOUT
&&
1684 sun3_dma_setup_done
!= cmd
) {
1687 if (!cmd
->SCp
.this_residual
&& cmd
->SCp
.buffers_residual
) {
1689 --cmd
->SCp
.buffers_residual
;
1690 cmd
->SCp
.this_residual
= cmd
->SCp
.buffer
->length
;
1691 cmd
->SCp
.ptr
= sg_virt(cmd
->SCp
.buffer
);
1694 count
= sun3scsi_dma_xfer_len(hostdata
, cmd
);
1697 if (rq_data_dir(cmd
->request
))
1698 sun3scsi_dma_send_setup(hostdata
,
1699 cmd
->SCp
.ptr
, count
);
1701 sun3scsi_dma_recv_setup(hostdata
,
1702 cmd
->SCp
.ptr
, count
);
1703 sun3_dma_setup_done
= cmd
;
1705 #ifdef SUN3_SCSI_VME
1706 dregs
->csr
|= CSR_INTR
;
1709 #endif /* CONFIG_SUN3 */
1711 if (sink
&& (phase
!= PHASE_MSGOUT
)) {
1712 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(tmp
));
1714 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
|
1716 while (NCR5380_read(STATUS_REG
) & SR_REQ
)
1718 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1726 #if (NDEBUG & NDEBUG_NO_DATAOUT)
1727 shost_printk(KERN_DEBUG
, instance
, "NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n");
1730 cmd
->result
= DID_ERROR
<< 16;
1731 complete_cmd(instance
, cmd
);
1732 hostdata
->connected
= NULL
;
1737 * If there is no room left in the current buffer in the
1738 * scatter-gather list, move onto the next one.
1741 if (!cmd
->SCp
.this_residual
&& cmd
->SCp
.buffers_residual
) {
1743 --cmd
->SCp
.buffers_residual
;
1744 cmd
->SCp
.this_residual
= cmd
->SCp
.buffer
->length
;
1745 cmd
->SCp
.ptr
= sg_virt(cmd
->SCp
.buffer
);
1746 dsprintk(NDEBUG_INFORMATION
, instance
, "%d bytes and %d buffers left\n",
1747 cmd
->SCp
.this_residual
,
1748 cmd
->SCp
.buffers_residual
);
1752 * The preferred transfer method is going to be
1753 * PSEUDO-DMA for systems that are strictly PIO,
1754 * since we can let the hardware do the handshaking.
1756 * For this to work, we need to know the transfersize
1757 * ahead of time, since the pseudo-DMA code will sit
1758 * in an unconditional loop.
1762 if (!cmd
->device
->borken
)
1763 transfersize
= NCR5380_dma_xfer_len(hostdata
, cmd
);
1765 if (transfersize
> 0) {
1767 if (NCR5380_transfer_dma(instance
, &phase
,
1768 &len
, (unsigned char **)&cmd
->SCp
.ptr
)) {
1770 * If the watchdog timer fires, all future
1771 * accesses to this device will use the
1774 scmd_printk(KERN_INFO
, cmd
,
1775 "switching to slow handshake\n");
1776 cmd
->device
->borken
= 1;
1779 cmd
->result
= DID_ERROR
<< 16;
1780 /* XXX - need to source or sink data here, as appropriate */
1783 /* Transfer a small chunk so that the
1784 * irq mode lock is not held too long.
1786 transfersize
= min(cmd
->SCp
.this_residual
,
1787 NCR5380_PIO_CHUNK_SIZE
);
1789 NCR5380_transfer_pio(instance
, &phase
, &len
,
1790 (unsigned char **)&cmd
->SCp
.ptr
);
1791 cmd
->SCp
.this_residual
-= transfersize
- len
;
1794 if (sun3_dma_setup_done
== cmd
)
1795 sun3_dma_setup_done
= NULL
;
1801 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
1802 cmd
->SCp
.Message
= tmp
;
1806 case COMMAND_COMPLETE
:
1807 /* Accept message by clearing ACK */
1809 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1810 dsprintk(NDEBUG_QUEUES
, instance
,
1811 "COMMAND COMPLETE %p target %d lun %llu\n",
1812 cmd
, scmd_id(cmd
), cmd
->device
->lun
);
1814 hostdata
->connected
= NULL
;
1816 cmd
->result
&= ~0xffff;
1817 cmd
->result
|= cmd
->SCp
.Status
;
1818 cmd
->result
|= cmd
->SCp
.Message
<< 8;
1820 if (cmd
->cmnd
[0] == REQUEST_SENSE
)
1821 complete_cmd(instance
, cmd
);
1823 if (cmd
->SCp
.Status
== SAM_STAT_CHECK_CONDITION
||
1824 cmd
->SCp
.Status
== SAM_STAT_COMMAND_TERMINATED
) {
1825 dsprintk(NDEBUG_QUEUES
, instance
, "autosense: adding cmd %p to tail of autosense queue\n",
1827 list_add_tail(&ncmd
->list
,
1828 &hostdata
->autosense
);
1830 complete_cmd(instance
, cmd
);
1834 * Restore phase bits to 0 so an interrupted selection,
1835 * arbitration can resume.
1837 NCR5380_write(TARGET_COMMAND_REG
, 0);
1839 /* Enable reselect interrupts */
1840 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1842 maybe_release_dma_irq(instance
);
1844 case MESSAGE_REJECT
:
1845 /* Accept message by clearing ACK */
1846 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1847 switch (hostdata
->last_message
) {
1848 case HEAD_OF_QUEUE_TAG
:
1849 case ORDERED_QUEUE_TAG
:
1850 case SIMPLE_QUEUE_TAG
:
1851 cmd
->device
->simple_tags
= 0;
1852 hostdata
->busy
[cmd
->device
->id
] |= (1 << (cmd
->device
->lun
& 0xFF));
1859 /* Accept message by clearing ACK */
1860 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1861 hostdata
->connected
= NULL
;
1862 list_add(&ncmd
->list
, &hostdata
->disconnected
);
1863 dsprintk(NDEBUG_INFORMATION
| NDEBUG_QUEUES
,
1864 instance
, "connected command %p for target %d lun %llu moved to disconnected queue\n",
1865 cmd
, scmd_id(cmd
), cmd
->device
->lun
);
1868 * Restore phase bits to 0 so an interrupted selection,
1869 * arbitration can resume.
1871 NCR5380_write(TARGET_COMMAND_REG
, 0);
1873 /* Enable reselect interrupts */
1874 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1875 #ifdef SUN3_SCSI_VME
1876 dregs
->csr
|= CSR_DMA_ENABLE
;
1880 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
1881 * operation, in violation of the SCSI spec so we can safely
1882 * ignore SAVE/RESTORE pointers calls.
1884 * Unfortunately, some disks violate the SCSI spec and
1885 * don't issue the required SAVE_POINTERS message before
1886 * disconnecting, and we have to break spec to remain
1890 case RESTORE_POINTERS
:
1891 /* Accept message by clearing ACK */
1892 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1894 case EXTENDED_MESSAGE
:
1896 * Start the message buffer with the EXTENDED_MESSAGE
1897 * byte, since spi_print_msg() wants the whole thing.
1899 extended_msg
[0] = EXTENDED_MESSAGE
;
1900 /* Accept first byte by clearing ACK */
1901 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1903 spin_unlock_irq(&hostdata
->lock
);
1905 dsprintk(NDEBUG_EXTENDED
, instance
, "receiving extended message\n");
1908 data
= extended_msg
+ 1;
1909 phase
= PHASE_MSGIN
;
1910 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
1911 dsprintk(NDEBUG_EXTENDED
, instance
, "length %d, code 0x%02x\n",
1912 (int)extended_msg
[1],
1913 (int)extended_msg
[2]);
1915 if (!len
&& extended_msg
[1] > 0 &&
1916 extended_msg
[1] <= sizeof(extended_msg
) - 2) {
1917 /* Accept third byte by clearing ACK */
1918 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1919 len
= extended_msg
[1] - 1;
1920 data
= extended_msg
+ 3;
1921 phase
= PHASE_MSGIN
;
1923 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
1924 dsprintk(NDEBUG_EXTENDED
, instance
, "message received, residual %d\n",
1927 switch (extended_msg
[2]) {
1930 case EXTENDED_MODIFY_DATA_POINTER
:
1931 case EXTENDED_EXTENDED_IDENTIFY
:
1935 shost_printk(KERN_ERR
, instance
, "error receiving extended message\n");
1938 shost_printk(KERN_NOTICE
, instance
, "extended message code %02x length %d is too long\n",
1939 extended_msg
[2], extended_msg
[1]);
1943 spin_lock_irq(&hostdata
->lock
);
1944 if (!hostdata
->connected
)
1947 /* Fall through to reject message */
1950 * If we get something weird that we aren't expecting,
1955 shost_printk(KERN_ERR
, instance
, "rejecting message ");
1956 spi_print_msg(extended_msg
);
1958 } else if (tmp
!= EXTENDED_MESSAGE
)
1959 scmd_printk(KERN_INFO
, cmd
,
1960 "rejecting unknown message %02x\n",
1963 scmd_printk(KERN_INFO
, cmd
,
1964 "rejecting unknown extended message code %02x, length %d\n",
1965 extended_msg
[1], extended_msg
[0]);
1967 msgout
= MESSAGE_REJECT
;
1968 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1970 } /* switch (tmp) */
1975 hostdata
->last_message
= msgout
;
1976 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
1977 if (msgout
== ABORT
) {
1978 hostdata
->connected
= NULL
;
1979 cmd
->result
= DID_ERROR
<< 16;
1980 complete_cmd(instance
, cmd
);
1981 maybe_release_dma_irq(instance
);
1982 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1991 * XXX for performance reasons, on machines with a
1992 * PSEUDO-DMA architecture we should probably
1993 * use the dma transfer function.
1995 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2000 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2001 cmd
->SCp
.Status
= tmp
;
2004 shost_printk(KERN_ERR
, instance
, "unknown phase\n");
2005 NCR5380_dprint(NDEBUG_ANY
, instance
);
2006 } /* switch(phase) */
2008 spin_unlock_irq(&hostdata
->lock
);
2009 NCR5380_poll_politely(hostdata
, STATUS_REG
, SR_REQ
, SR_REQ
, HZ
);
2010 spin_lock_irq(&hostdata
->lock
);
2016 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2018 * Purpose : does reselection, initializing the instance->connected
2019 * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
2020 * nexus has been reestablished,
2022 * Inputs : instance - this instance of the NCR5380.
2025 static void NCR5380_reselect(struct Scsi_Host
*instance
)
2027 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
2028 unsigned char target_mask
;
2030 unsigned char msg
[3];
2031 struct NCR5380_cmd
*ncmd
;
2032 struct scsi_cmnd
*tmp
;
2035 * Disable arbitration, etc. since the host adapter obviously
2036 * lost, and tell an interrupted NCR5380_select() to restart.
2039 NCR5380_write(MODE_REG
, MR_BASE
);
2041 target_mask
= NCR5380_read(CURRENT_SCSI_DATA_REG
) & ~(hostdata
->id_mask
);
2043 dsprintk(NDEBUG_RESELECTION
, instance
, "reselect\n");
2046 * At this point, we have detected that our SCSI ID is on the bus,
2047 * SEL is true and BSY was false for at least one bus settle delay
2050 * We must assert BSY ourselves, until the target drops the SEL
2054 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_BSY
);
2055 if (NCR5380_poll_politely(hostdata
,
2056 STATUS_REG
, SR_SEL
, 0, 2 * HZ
) < 0) {
2057 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2060 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2063 * Wait for target to go into MSGIN.
2066 if (NCR5380_poll_politely(hostdata
,
2067 STATUS_REG
, SR_REQ
, SR_REQ
, 2 * HZ
) < 0) {
2073 /* acknowledge toggle to MSGIN */
2074 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(PHASE_MSGIN
));
2076 /* peek at the byte without really hitting the bus */
2077 msg
[0] = NCR5380_read(CURRENT_SCSI_DATA_REG
);
2081 unsigned char *data
= msg
;
2082 unsigned char phase
= PHASE_MSGIN
;
2084 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2091 #endif /* CONFIG_SUN3 */
2093 if (!(msg
[0] & 0x80)) {
2094 shost_printk(KERN_ERR
, instance
, "expecting IDENTIFY message, got ");
2100 lun
= msg
[0] & 0x07;
2103 * We need to add code for SCSI-II to track which devices have
2104 * I_T_L_Q nexuses established, and which have simple I_T_L
2105 * nexuses so we can chose to do additional data transfer.
2109 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2110 * just reestablished, and remove it from the disconnected queue.
2114 list_for_each_entry(ncmd
, &hostdata
->disconnected
, list
) {
2115 struct scsi_cmnd
*cmd
= NCR5380_to_scmd(ncmd
);
2117 if (target_mask
== (1 << scmd_id(cmd
)) &&
2118 lun
== (u8
)cmd
->device
->lun
) {
2119 list_del(&ncmd
->list
);
2126 dsprintk(NDEBUG_RESELECTION
| NDEBUG_QUEUES
, instance
,
2127 "reselect: removed %p from disconnected queue\n", tmp
);
2129 shost_printk(KERN_ERR
, instance
, "target bitmask 0x%02x lun %d not in disconnected queue.\n",
2132 * Since we have an established nexus that we can't do anything
2133 * with, we must abort it.
2140 if (sun3_dma_setup_done
!= tmp
) {
2143 if (!tmp
->SCp
.this_residual
&& tmp
->SCp
.buffers_residual
) {
2145 --tmp
->SCp
.buffers_residual
;
2146 tmp
->SCp
.this_residual
= tmp
->SCp
.buffer
->length
;
2147 tmp
->SCp
.ptr
= sg_virt(tmp
->SCp
.buffer
);
2150 count
= sun3scsi_dma_xfer_len(hostdata
, tmp
);
2153 if (rq_data_dir(tmp
->request
))
2154 sun3scsi_dma_send_setup(hostdata
,
2155 tmp
->SCp
.ptr
, count
);
2157 sun3scsi_dma_recv_setup(hostdata
,
2158 tmp
->SCp
.ptr
, count
);
2159 sun3_dma_setup_done
= tmp
;
2163 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ACK
);
2164 #endif /* CONFIG_SUN3 */
2166 /* Accept message by clearing ACK */
2167 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2169 hostdata
->connected
= tmp
;
2170 dsprintk(NDEBUG_RESELECTION
, instance
, "nexus established, target %d, lun %llu\n",
2171 scmd_id(tmp
), tmp
->device
->lun
);
2175 * list_find_cmd - test for presence of a command in a linked list
2176 * @haystack: list of commands
2177 * @needle: command to search for
2180 static bool list_find_cmd(struct list_head
*haystack
,
2181 struct scsi_cmnd
*needle
)
2183 struct NCR5380_cmd
*ncmd
;
2185 list_for_each_entry(ncmd
, haystack
, list
)
2186 if (NCR5380_to_scmd(ncmd
) == needle
)
2192 * list_remove_cmd - remove a command from linked list
2193 * @haystack: list of commands
2194 * @needle: command to remove
2197 static bool list_del_cmd(struct list_head
*haystack
,
2198 struct scsi_cmnd
*needle
)
2200 if (list_find_cmd(haystack
, needle
)) {
2201 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(needle
);
2203 list_del(&ncmd
->list
);
2210 * NCR5380_abort - scsi host eh_abort_handler() method
2211 * @cmd: the command to be aborted
2213 * Try to abort a given command by removing it from queues and/or sending
2214 * the target an abort message. This may not succeed in causing a target
2215 * to abort the command. Nonetheless, the low-level driver must forget about
2216 * the command because the mid-layer reclaims it and it may be re-issued.
2218 * The normal path taken by a command is as follows. For EH we trace this
2219 * same path to locate and abort the command.
2221 * unissued -> selecting -> [unissued -> selecting ->]... connected ->
2222 * [disconnected -> connected ->]...
2223 * [autosense -> connected ->] done
2225 * If cmd was not found at all then presumably it has already been completed,
2226 * in which case return SUCCESS to try to avoid further EH measures.
2228 * If the command has not completed yet, we must not fail to find it.
2229 * We have no option but to forget the aborted command (even if it still
2230 * lacks sense data). The mid-layer may re-issue a command that is in error
2231 * recovery (see scsi_send_eh_cmnd), but the logic and data structures in
2232 * this driver are such that a command can appear on one queue only.
2234 * The lock protects driver data structures, but EH handlers also use it
2235 * to serialize their own execution and prevent their own re-entry.
2238 static int NCR5380_abort(struct scsi_cmnd
*cmd
)
2240 struct Scsi_Host
*instance
= cmd
->device
->host
;
2241 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
2242 unsigned long flags
;
2243 int result
= SUCCESS
;
2245 spin_lock_irqsave(&hostdata
->lock
, flags
);
2247 #if (NDEBUG & NDEBUG_ANY)
2248 scmd_printk(KERN_INFO
, cmd
, __func__
);
2250 NCR5380_dprint(NDEBUG_ANY
, instance
);
2251 NCR5380_dprint_phase(NDEBUG_ANY
, instance
);
2253 if (list_del_cmd(&hostdata
->unissued
, cmd
)) {
2254 dsprintk(NDEBUG_ABORT
, instance
,
2255 "abort: removed %p from issue queue\n", cmd
);
2256 cmd
->result
= DID_ABORT
<< 16;
2257 cmd
->scsi_done(cmd
); /* No tag or busy flag to worry about */
2261 if (hostdata
->selecting
== cmd
) {
2262 dsprintk(NDEBUG_ABORT
, instance
,
2263 "abort: cmd %p == selecting\n", cmd
);
2264 hostdata
->selecting
= NULL
;
2265 cmd
->result
= DID_ABORT
<< 16;
2266 complete_cmd(instance
, cmd
);
2270 if (list_del_cmd(&hostdata
->disconnected
, cmd
)) {
2271 dsprintk(NDEBUG_ABORT
, instance
,
2272 "abort: removed %p from disconnected list\n", cmd
);
2273 /* Can't call NCR5380_select() and send ABORT because that
2274 * means releasing the lock. Need a bus reset.
2276 set_host_byte(cmd
, DID_ERROR
);
2277 complete_cmd(instance
, cmd
);
2282 if (hostdata
->connected
== cmd
) {
2283 dsprintk(NDEBUG_ABORT
, instance
, "abort: cmd %p is connected\n", cmd
);
2284 hostdata
->connected
= NULL
;
2285 hostdata
->dma_len
= 0;
2286 if (do_abort(instance
)) {
2287 set_host_byte(cmd
, DID_ERROR
);
2288 complete_cmd(instance
, cmd
);
2292 set_host_byte(cmd
, DID_ABORT
);
2293 complete_cmd(instance
, cmd
);
2297 if (list_del_cmd(&hostdata
->autosense
, cmd
)) {
2298 dsprintk(NDEBUG_ABORT
, instance
,
2299 "abort: removed %p from sense queue\n", cmd
);
2300 set_host_byte(cmd
, DID_ERROR
);
2301 complete_cmd(instance
, cmd
);
2305 if (result
== FAILED
)
2306 dsprintk(NDEBUG_ABORT
, instance
, "abort: failed to abort %p\n", cmd
);
2308 dsprintk(NDEBUG_ABORT
, instance
, "abort: successfully aborted %p\n", cmd
);
2310 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
2311 maybe_release_dma_irq(instance
);
2312 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
2319 * NCR5380_bus_reset - reset the SCSI bus
2320 * @cmd: SCSI command undergoing EH
2325 static int NCR5380_bus_reset(struct scsi_cmnd
*cmd
)
2327 struct Scsi_Host
*instance
= cmd
->device
->host
;
2328 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
2330 unsigned long flags
;
2331 struct NCR5380_cmd
*ncmd
;
2333 spin_lock_irqsave(&hostdata
->lock
, flags
);
2335 #if (NDEBUG & NDEBUG_ANY)
2336 scmd_printk(KERN_INFO
, cmd
, __func__
);
2338 NCR5380_dprint(NDEBUG_ANY
, instance
);
2339 NCR5380_dprint_phase(NDEBUG_ANY
, instance
);
2343 /* reset NCR registers */
2344 NCR5380_write(MODE_REG
, MR_BASE
);
2345 NCR5380_write(TARGET_COMMAND_REG
, 0);
2346 NCR5380_write(SELECT_ENABLE_REG
, 0);
2348 /* After the reset, there are no more connected or disconnected commands
2349 * and no busy units; so clear the low-level status here to avoid
2350 * conflicts when the mid-level code tries to wake up the affected
2354 if (list_del_cmd(&hostdata
->unissued
, cmd
)) {
2355 cmd
->result
= DID_RESET
<< 16;
2356 cmd
->scsi_done(cmd
);
2359 if (hostdata
->selecting
) {
2360 hostdata
->selecting
->result
= DID_RESET
<< 16;
2361 complete_cmd(instance
, hostdata
->selecting
);
2362 hostdata
->selecting
= NULL
;
2365 list_for_each_entry(ncmd
, &hostdata
->disconnected
, list
) {
2366 struct scsi_cmnd
*cmd
= NCR5380_to_scmd(ncmd
);
2368 set_host_byte(cmd
, DID_RESET
);
2369 complete_cmd(instance
, cmd
);
2371 INIT_LIST_HEAD(&hostdata
->disconnected
);
2373 list_for_each_entry(ncmd
, &hostdata
->autosense
, list
) {
2374 struct scsi_cmnd
*cmd
= NCR5380_to_scmd(ncmd
);
2376 set_host_byte(cmd
, DID_RESET
);
2377 cmd
->scsi_done(cmd
);
2379 INIT_LIST_HEAD(&hostdata
->autosense
);
2381 if (hostdata
->connected
) {
2382 set_host_byte(hostdata
->connected
, DID_RESET
);
2383 complete_cmd(instance
, hostdata
->connected
);
2384 hostdata
->connected
= NULL
;
2387 for (i
= 0; i
< 8; ++i
)
2388 hostdata
->busy
[i
] = 0;
2389 hostdata
->dma_len
= 0;
2391 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
2392 maybe_release_dma_irq(instance
);
2393 spin_unlock_irqrestore(&hostdata
->lock
, flags
);