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
27 /* Ported to Atari by Roman Hodek and others. */
29 /* Adapted for the sun3 by Sam Creasey. */
34 * This is a generic 5380 driver. To use it on a different platform,
35 * one simply writes appropriate system specific macros (ie, data
36 * transfer - some PC's will use the I/O bus, 68K's must use
37 * memory mapped) and drops this file in their 'C' wrapper.
39 * As far as command queueing, two queues are maintained for
40 * each 5380 in the system - commands that haven't been issued yet,
41 * and commands that are currently executing. This means that an
42 * unlimited number of commands may be queued, letting
43 * more commands propagate from the higher driver levels giving higher
44 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
45 * allowing multiple commands to propagate all the way to a SCSI-II device
46 * while a command is already executing.
49 * Issues specific to the NCR5380 :
51 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
52 * piece of hardware that requires you to sit in a loop polling for
53 * the REQ signal as long as you are connected. Some devices are
54 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
55 * while doing long seek operations. [...] These
56 * broken devices are the exception rather than the rule and I'd rather
57 * spend my time optimizing for the normal case.
61 * At the heart of the design is a coroutine, NCR5380_main,
62 * which is started from a workqueue for each NCR5380 host in the
63 * system. It attempts to establish I_T_L or I_T_L_Q nexuses by
64 * removing the commands from the issue queue and calling
65 * NCR5380_select() if a nexus is not established.
67 * Once a nexus is established, the NCR5380_information_transfer()
68 * phase goes through the various phases as instructed by the target.
69 * if the target goes into MSG IN and sends a DISCONNECT message,
70 * the command structure is placed into the per instance disconnected
71 * queue, and NCR5380_main tries to find more work. If the target is
72 * idle for too long, the system will try to sleep.
74 * If a command has disconnected, eventually an interrupt will trigger,
75 * calling NCR5380_intr() which will in turn call NCR5380_reselect
76 * to reestablish a nexus. This will run main if necessary.
78 * On command termination, the done function will be called as
81 * SCSI pointers are maintained in the SCp field of SCSI command
82 * structures, being initialized after the command is connected
83 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
84 * Note that in violation of the standard, an implicit SAVE POINTERS operation
85 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
90 * This file a skeleton Linux SCSI driver for the NCR 5380 series
91 * of chips. To use it, you write an architecture specific functions
92 * and macros and include this file in your driver.
94 * These macros control options :
95 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
96 * for commands that return with a CHECK CONDITION status.
98 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
101 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
103 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
105 * These macros MUST be defined :
107 * NCR5380_read(register) - read from the specified register
109 * NCR5380_write(register, value) - write to the specific register
111 * NCR5380_implementation_fields - additional fields needed for this
112 * specific implementation of the NCR5380
114 * Either real DMA *or* pseudo DMA may be implemented
116 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
117 * Note that the DMA setup functions should return the number of bytes
118 * that they were able to program the controller for.
120 * Also note that generic i386/PC versions of these macros are
121 * available as NCR5380_i386_dma_write_setup,
122 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
124 * NCR5380_dma_write_setup(instance, src, count) - initialize
125 * NCR5380_dma_read_setup(instance, dst, count) - initialize
126 * NCR5380_dma_residual(instance); - residual count
129 * NCR5380_pwrite(instance, src, count)
130 * NCR5380_pread(instance, dst, count);
132 * The generic driver is initialized by calling NCR5380_init(instance),
133 * after setting the appropriate host specific fields and ID. If the
134 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
135 * possible) function may be used.
138 static int do_abort(struct Scsi_Host
*);
139 static void do_reset(struct Scsi_Host
*);
144 * Functions for handling tagged queuing
145 * =====================================
147 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
149 * Using consecutive numbers for the tags is no good idea in my eyes. There
150 * could be wrong re-usings if the counter (8 bit!) wraps and some early
151 * command has been preempted for a long time. My solution: a bitfield for
152 * remembering used tags.
154 * There's also the problem that each target has a certain queue size, but we
155 * cannot know it in advance :-( We just see a QUEUE_FULL status being
156 * returned. So, in this case, the driver internal queue size assumption is
157 * reduced to the number of active tags if QUEUE_FULL is returned by the
160 * We're also not allowed running tagged commands as long as an untagged
161 * command is active. And REQUEST SENSE commands after a contingent allegiance
162 * condition _must_ be untagged. To keep track whether an untagged command has
163 * been issued, the host->busy array is still employed, as it is without
164 * support for tagged queuing.
166 * One could suspect that there are possible race conditions between
167 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
168 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
169 * which already guaranteed to be running at most once. It is also the only
170 * place where tags/LUNs are allocated. So no other allocation can slip
171 * between that pair, there could only happen a reselection, which can free a
172 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
173 * important: the tag bit must be cleared before 'nr_allocated' is decreased.
176 static void __init
init_tags(struct NCR5380_hostdata
*hostdata
)
179 struct tag_alloc
*ta
;
181 if (!(hostdata
->flags
& FLAG_TAGGED_QUEUING
))
184 for (target
= 0; target
< 8; ++target
) {
185 for (lun
= 0; lun
< 8; ++lun
) {
186 ta
= &hostdata
->TagAlloc
[target
][lun
];
187 bitmap_zero(ta
->allocated
, MAX_TAGS
);
188 ta
->nr_allocated
= 0;
189 /* At the beginning, assume the maximum queue size we could
190 * support (MAX_TAGS). This value will be decreased if the target
191 * returns QUEUE_FULL status.
193 ta
->queue_size
= MAX_TAGS
;
199 /* Check if we can issue a command to this LUN: First see if the LUN is marked
200 * busy by an untagged command. If the command should use tagged queuing, also
201 * check that there is a free tag and the target's queue won't overflow. This
202 * function should be called with interrupts disabled to avoid race
206 static int is_lun_busy(struct scsi_cmnd
*cmd
, int should_be_tagged
)
208 u8 lun
= cmd
->device
->lun
;
209 struct Scsi_Host
*instance
= cmd
->device
->host
;
210 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
212 if (hostdata
->busy
[cmd
->device
->id
] & (1 << lun
))
214 if (!should_be_tagged
||
215 !(hostdata
->flags
& FLAG_TAGGED_QUEUING
) ||
216 !cmd
->device
->tagged_supported
)
218 if (hostdata
->TagAlloc
[scmd_id(cmd
)][lun
].nr_allocated
>=
219 hostdata
->TagAlloc
[scmd_id(cmd
)][lun
].queue_size
) {
220 dsprintk(NDEBUG_TAGS
, instance
, "target %d lun %d: no free tags\n",
228 /* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
229 * must be called before!), or reserve the LUN in 'busy' if the command is
233 static void cmd_get_tag(struct scsi_cmnd
*cmd
, int should_be_tagged
)
235 u8 lun
= cmd
->device
->lun
;
236 struct Scsi_Host
*instance
= cmd
->device
->host
;
237 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
239 /* If we or the target don't support tagged queuing, allocate the LUN for
240 * an untagged command.
242 if (!should_be_tagged
||
243 !(hostdata
->flags
& FLAG_TAGGED_QUEUING
) ||
244 !cmd
->device
->tagged_supported
) {
246 hostdata
->busy
[cmd
->device
->id
] |= (1 << lun
);
247 dsprintk(NDEBUG_TAGS
, instance
, "target %d lun %d now allocated by untagged command\n",
250 struct tag_alloc
*ta
= &hostdata
->TagAlloc
[scmd_id(cmd
)][lun
];
252 cmd
->tag
= find_first_zero_bit(ta
->allocated
, MAX_TAGS
);
253 set_bit(cmd
->tag
, ta
->allocated
);
255 dsprintk(NDEBUG_TAGS
, instance
, "using tag %d for target %d lun %d (%d tags allocated)\n",
256 cmd
->tag
, scmd_id(cmd
), lun
, ta
->nr_allocated
);
261 /* Mark the tag of command 'cmd' as free, or in case of an untagged command,
265 static void cmd_free_tag(struct scsi_cmnd
*cmd
)
267 u8 lun
= cmd
->device
->lun
;
268 struct Scsi_Host
*instance
= cmd
->device
->host
;
269 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
271 if (cmd
->tag
== TAG_NONE
) {
272 hostdata
->busy
[cmd
->device
->id
] &= ~(1 << lun
);
273 dsprintk(NDEBUG_TAGS
, instance
, "target %d lun %d untagged cmd freed\n",
275 } else if (cmd
->tag
>= MAX_TAGS
) {
276 shost_printk(KERN_NOTICE
, instance
,
277 "trying to free bad tag %d!\n", cmd
->tag
);
279 struct tag_alloc
*ta
= &hostdata
->TagAlloc
[scmd_id(cmd
)][lun
];
280 clear_bit(cmd
->tag
, ta
->allocated
);
282 dsprintk(NDEBUG_TAGS
, instance
, "freed tag %d for target %d lun %d\n",
283 cmd
->tag
, scmd_id(cmd
), lun
);
288 static void free_all_tags(struct NCR5380_hostdata
*hostdata
)
291 struct tag_alloc
*ta
;
293 if (!(hostdata
->flags
& FLAG_TAGGED_QUEUING
))
296 for (target
= 0; target
< 8; ++target
) {
297 for (lun
= 0; lun
< 8; ++lun
) {
298 ta
= &hostdata
->TagAlloc
[target
][lun
];
299 bitmap_zero(ta
->allocated
, MAX_TAGS
);
300 ta
->nr_allocated
= 0;
305 #endif /* SUPPORT_TAGS */
308 * merge_contiguous_buffers - coalesce scatter-gather list entries
309 * @cmd: command requesting IO
311 * Try to merge several scatter-gather buffers into one DMA transfer.
312 * This is possible if the scatter buffers lie on physically
313 * contiguous addresses. The first scatter-gather buffer's data are
314 * assumed to be already transferred into cmd->SCp.this_residual.
315 * Every buffer merged avoids an interrupt and a DMA setup operation.
318 static void merge_contiguous_buffers(struct scsi_cmnd
*cmd
)
320 #if !defined(CONFIG_SUN3)
321 unsigned long endaddr
;
322 #if (NDEBUG & NDEBUG_MERGING)
323 unsigned long oldlen
= cmd
->SCp
.this_residual
;
327 for (endaddr
= virt_to_phys(cmd
->SCp
.ptr
+ cmd
->SCp
.this_residual
- 1) + 1;
328 cmd
->SCp
.buffers_residual
&&
329 virt_to_phys(sg_virt(&cmd
->SCp
.buffer
[1])) == endaddr
;) {
330 dprintk(NDEBUG_MERGING
, "VTOP(%p) == %08lx -> merging\n",
331 page_address(sg_page(&cmd
->SCp
.buffer
[1])), endaddr
);
332 #if (NDEBUG & NDEBUG_MERGING)
336 --cmd
->SCp
.buffers_residual
;
337 cmd
->SCp
.this_residual
+= cmd
->SCp
.buffer
->length
;
338 endaddr
+= cmd
->SCp
.buffer
->length
;
340 #if (NDEBUG & NDEBUG_MERGING)
341 if (oldlen
!= cmd
->SCp
.this_residual
)
342 dprintk(NDEBUG_MERGING
, "merged %d buffers from %p, new length %08x\n",
343 cnt
, cmd
->SCp
.ptr
, cmd
->SCp
.this_residual
);
345 #endif /* !defined(CONFIG_SUN3) */
349 * initialize_SCp - init the scsi pointer field
350 * @cmd: command block to set up
352 * Set up the internal fields in the SCSI command.
355 static inline void initialize_SCp(struct scsi_cmnd
*cmd
)
358 * Initialize the Scsi Pointer field so that all of the commands in the
359 * various queues are valid.
362 if (scsi_bufflen(cmd
)) {
363 cmd
->SCp
.buffer
= scsi_sglist(cmd
);
364 cmd
->SCp
.buffers_residual
= scsi_sg_count(cmd
) - 1;
365 cmd
->SCp
.ptr
= sg_virt(cmd
->SCp
.buffer
);
366 cmd
->SCp
.this_residual
= cmd
->SCp
.buffer
->length
;
368 merge_contiguous_buffers(cmd
);
370 cmd
->SCp
.buffer
= NULL
;
371 cmd
->SCp
.buffers_residual
= 0;
373 cmd
->SCp
.this_residual
= 0;
377 cmd
->SCp
.Message
= 0;
381 * NCR5380_poll_politely2 - wait for two chip register values
382 * @instance: controller to poll
383 * @reg1: 5380 register to poll
384 * @bit1: Bitmask to check
385 * @val1: Expected value
386 * @reg2: Second 5380 register to poll
387 * @bit2: Second bitmask to check
388 * @val2: Second expected value
389 * @wait: Time-out in jiffies
391 * Polls the chip in a reasonably efficient manner waiting for an
392 * event to occur. After a short quick poll we begin to yield the CPU
393 * (if possible). In irq contexts the time-out is arbitrarily limited.
394 * Callers may hold locks as long as they are held in irq mode.
396 * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.
399 static int NCR5380_poll_politely2(struct Scsi_Host
*instance
,
400 int reg1
, int bit1
, int val1
,
401 int reg2
, int bit2
, int val2
, int wait
)
403 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
404 unsigned long deadline
= jiffies
+ wait
;
407 /* Busy-wait for up to 10 ms */
408 n
= min(10000U, jiffies_to_usecs(wait
));
409 n
*= hostdata
->accesses_per_ms
;
412 if ((NCR5380_read(reg1
) & bit1
) == val1
)
414 if ((NCR5380_read(reg2
) & bit2
) == val2
)
419 if (irqs_disabled() || in_interrupt())
422 /* Repeatedly sleep for 1 ms until deadline */
423 while (time_is_after_jiffies(deadline
)) {
424 schedule_timeout_uninterruptible(1);
425 if ((NCR5380_read(reg1
) & bit1
) == val1
)
427 if ((NCR5380_read(reg2
) & bit2
) == val2
)
434 static inline int NCR5380_poll_politely(struct Scsi_Host
*instance
,
435 int reg
, int bit
, int val
, int wait
)
437 return NCR5380_poll_politely2(instance
, reg
, bit
, val
,
438 reg
, bit
, val
, wait
);
462 {ICR_ASSERT_RST
, "ASSERT RST"},
463 {ICR_ASSERT_ACK
, "ASSERT ACK"},
464 {ICR_ASSERT_BSY
, "ASSERT BSY"},
465 {ICR_ASSERT_SEL
, "ASSERT SEL"},
466 {ICR_ASSERT_ATN
, "ASSERT ATN"},
467 {ICR_ASSERT_DATA
, "ASSERT DATA"},
471 {MR_BLOCK_DMA_MODE
, "MODE BLOCK DMA"},
472 {MR_TARGET
, "MODE TARGET"},
473 {MR_ENABLE_PAR_CHECK
, "MODE PARITY CHECK"},
474 {MR_ENABLE_PAR_INTR
, "MODE PARITY INTR"},
475 {MR_ENABLE_EOP_INTR
, "MODE EOP INTR"},
476 {MR_MONITOR_BSY
, "MODE MONITOR BSY"},
477 {MR_DMA_MODE
, "MODE DMA"},
478 {MR_ARBITRATE
, "MODE ARBITRATION"},
483 * NCR5380_print - print scsi bus signals
484 * @instance: adapter state to dump
486 * Print the SCSI bus signals for debugging purposes
489 static void NCR5380_print(struct Scsi_Host
*instance
)
491 unsigned char status
, data
, basr
, mr
, icr
, i
;
493 data
= NCR5380_read(CURRENT_SCSI_DATA_REG
);
494 status
= NCR5380_read(STATUS_REG
);
495 mr
= NCR5380_read(MODE_REG
);
496 icr
= NCR5380_read(INITIATOR_COMMAND_REG
);
497 basr
= NCR5380_read(BUS_AND_STATUS_REG
);
499 printk("STATUS_REG: %02x ", status
);
500 for (i
= 0; signals
[i
].mask
; ++i
)
501 if (status
& signals
[i
].mask
)
502 printk(",%s", signals
[i
].name
);
503 printk("\nBASR: %02x ", basr
);
504 for (i
= 0; basrs
[i
].mask
; ++i
)
505 if (basr
& basrs
[i
].mask
)
506 printk(",%s", basrs
[i
].name
);
507 printk("\nICR: %02x ", icr
);
508 for (i
= 0; icrs
[i
].mask
; ++i
)
509 if (icr
& icrs
[i
].mask
)
510 printk(",%s", icrs
[i
].name
);
511 printk("\nMODE: %02x ", mr
);
512 for (i
= 0; mrs
[i
].mask
; ++i
)
513 if (mr
& mrs
[i
].mask
)
514 printk(",%s", mrs
[i
].name
);
522 {PHASE_DATAOUT
, "DATAOUT"},
523 {PHASE_DATAIN
, "DATAIN"},
524 {PHASE_CMDOUT
, "CMDOUT"},
525 {PHASE_STATIN
, "STATIN"},
526 {PHASE_MSGOUT
, "MSGOUT"},
527 {PHASE_MSGIN
, "MSGIN"},
528 {PHASE_UNKNOWN
, "UNKNOWN"}
532 * NCR5380_print_phase - show SCSI phase
533 * @instance: adapter to dump
535 * Print the current SCSI phase for debugging purposes
538 static void NCR5380_print_phase(struct Scsi_Host
*instance
)
540 unsigned char status
;
543 status
= NCR5380_read(STATUS_REG
);
544 if (!(status
& SR_REQ
))
545 shost_printk(KERN_DEBUG
, instance
, "REQ not asserted, phase unknown.\n");
547 for (i
= 0; (phases
[i
].value
!= PHASE_UNKNOWN
) &&
548 (phases
[i
].value
!= (status
& PHASE_MASK
)); ++i
)
550 shost_printk(KERN_DEBUG
, instance
, "phase %s\n", phases
[i
].name
);
556 * NCR58380_info - report driver and host information
557 * @instance: relevant scsi host instance
559 * For use as the host template info() handler.
562 static const char *NCR5380_info(struct Scsi_Host
*instance
)
564 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
566 return hostdata
->info
;
569 static void prepare_info(struct Scsi_Host
*instance
)
571 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
573 snprintf(hostdata
->info
, sizeof(hostdata
->info
),
574 "%s, io_port 0x%lx, n_io_port %d, "
575 "base 0x%lx, irq %d, "
576 "can_queue %d, cmd_per_lun %d, "
577 "sg_tablesize %d, this_id %d, "
580 instance
->hostt
->name
, instance
->io_port
, instance
->n_io_port
,
581 instance
->base
, instance
->irq
,
582 instance
->can_queue
, instance
->cmd_per_lun
,
583 instance
->sg_tablesize
, instance
->this_id
,
584 hostdata
->flags
& FLAG_TAGGED_QUEUING
? "TAGGED_QUEUING " : "",
585 hostdata
->flags
& FLAG_TOSHIBA_DELAY
? "TOSHIBA_DELAY " : "",
602 * NCR5380_init - initialise an NCR5380
603 * @instance: adapter to configure
604 * @flags: control flags
606 * Initializes *instance and corresponding 5380 chip,
607 * with flags OR'd into the initial flags value.
609 * Notes : I assume that the host, hostno, and id bits have been
610 * set correctly. I don't care about the irq and other fields.
612 * Returns 0 for success
615 static int __init
NCR5380_init(struct Scsi_Host
*instance
, int flags
)
617 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
619 unsigned long deadline
;
621 hostdata
->host
= instance
;
622 hostdata
->id_mask
= 1 << instance
->this_id
;
623 hostdata
->id_higher_mask
= 0;
624 for (i
= hostdata
->id_mask
; i
<= 0x80; i
<<= 1)
625 if (i
> hostdata
->id_mask
)
626 hostdata
->id_higher_mask
|= i
;
627 for (i
= 0; i
< 8; ++i
)
628 hostdata
->busy
[i
] = 0;
632 #if defined (REAL_DMA)
633 hostdata
->dma_len
= 0;
635 spin_lock_init(&hostdata
->lock
);
636 hostdata
->connected
= NULL
;
637 hostdata
->sensing
= NULL
;
638 INIT_LIST_HEAD(&hostdata
->autosense
);
639 INIT_LIST_HEAD(&hostdata
->unissued
);
640 INIT_LIST_HEAD(&hostdata
->disconnected
);
642 hostdata
->flags
= flags
;
644 INIT_WORK(&hostdata
->main_task
, NCR5380_main
);
645 hostdata
->work_q
= alloc_workqueue("ncr5380_%d",
646 WQ_UNBOUND
| WQ_MEM_RECLAIM
,
647 1, instance
->host_no
);
648 if (!hostdata
->work_q
)
651 prepare_info(instance
);
653 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
654 NCR5380_write(MODE_REG
, MR_BASE
);
655 NCR5380_write(TARGET_COMMAND_REG
, 0);
656 NCR5380_write(SELECT_ENABLE_REG
, 0);
658 /* Calibrate register polling loop */
660 deadline
= jiffies
+ 1;
663 } while (time_is_after_jiffies(deadline
));
664 deadline
+= msecs_to_jiffies(256);
666 NCR5380_read(STATUS_REG
);
669 } while (time_is_after_jiffies(deadline
));
670 hostdata
->accesses_per_ms
= i
/ 256;
676 * NCR5380_maybe_reset_bus - Detect and correct bus wedge problems.
677 * @instance: adapter to check
679 * If the system crashed, it may have crashed with a connected target and
680 * the SCSI bus busy. Check for BUS FREE phase. If not, try to abort the
681 * currently established nexus, which we know nothing about. Failing that
684 * Note that a bus reset will cause the chip to assert IRQ.
686 * Returns 0 if successful, otherwise -ENXIO.
689 static int NCR5380_maybe_reset_bus(struct Scsi_Host
*instance
)
691 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
694 for (pass
= 1; (NCR5380_read(STATUS_REG
) & SR_BSY
) && pass
<= 6; ++pass
) {
699 shost_printk(KERN_ERR
, instance
, "SCSI bus busy, waiting up to five seconds\n");
700 NCR5380_poll_politely(instance
,
701 STATUS_REG
, SR_BSY
, 0, 5 * HZ
);
704 shost_printk(KERN_ERR
, instance
, "bus busy, attempting abort\n");
708 shost_printk(KERN_ERR
, instance
, "bus busy, attempting reset\n");
710 /* Wait after a reset; the SCSI standard calls for
711 * 250ms, we wait 500ms to be on the safe side.
712 * But some Toshiba CD-ROMs need ten times that.
714 if (hostdata
->flags
& FLAG_TOSHIBA_DELAY
)
720 shost_printk(KERN_ERR
, instance
, "bus locked solid\n");
728 * NCR5380_exit - remove an NCR5380
729 * @instance: adapter to remove
731 * Assumes that no more work can be queued (e.g. by NCR5380_intr).
734 static void NCR5380_exit(struct Scsi_Host
*instance
)
736 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
738 cancel_work_sync(&hostdata
->main_task
);
739 destroy_workqueue(hostdata
->work_q
);
743 * complete_cmd - finish processing a command and return it to the SCSI ML
744 * @instance: the host instance
745 * @cmd: command to complete
748 static void complete_cmd(struct Scsi_Host
*instance
,
749 struct scsi_cmnd
*cmd
)
751 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
753 dsprintk(NDEBUG_QUEUES
, instance
, "complete_cmd: cmd %p\n", cmd
);
755 if (hostdata
->sensing
== cmd
) {
756 /* Autosense processing ends here */
757 if ((cmd
->result
& 0xff) != SAM_STAT_GOOD
) {
758 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
759 set_host_byte(cmd
, DID_ERROR
);
761 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
762 hostdata
->sensing
= NULL
;
768 hostdata
->busy
[scmd_id(cmd
)] &= ~(1 << cmd
->device
->lun
);
774 * NCR5380_queue_command - queue a command
775 * @instance: the relevant SCSI adapter
778 * cmd is added to the per-instance issue queue, with minor
779 * twiddling done to the host specific fields of cmd. If the
780 * main coroutine is not running, it is restarted.
783 static int NCR5380_queue_command(struct Scsi_Host
*instance
,
784 struct scsi_cmnd
*cmd
)
786 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
787 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
790 #if (NDEBUG & NDEBUG_NO_WRITE)
791 switch (cmd
->cmnd
[0]) {
794 shost_printk(KERN_DEBUG
, instance
, "WRITE attempted with NDEBUG_NO_WRITE set\n");
795 cmd
->result
= (DID_ERROR
<< 16);
799 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
804 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
805 * because also a timer int can trigger an abort or reset, which would
806 * alter queues and touch the lock.
808 if (!NCR5380_acquire_dma_irq(instance
))
809 return SCSI_MLQUEUE_HOST_BUSY
;
811 spin_lock_irqsave(&hostdata
->lock
, flags
);
814 * Insert the cmd into the issue queue. Note that REQUEST SENSE
815 * commands are added to the head of the queue since any command will
816 * clear the contingent allegiance condition that exists and the
817 * sense data is only guaranteed to be valid while the condition exists.
820 if (cmd
->cmnd
[0] == REQUEST_SENSE
)
821 list_add(&ncmd
->list
, &hostdata
->unissued
);
823 list_add_tail(&ncmd
->list
, &hostdata
->unissued
);
825 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
827 dsprintk(NDEBUG_QUEUES
, instance
, "command %p added to %s of queue\n",
828 cmd
, (cmd
->cmnd
[0] == REQUEST_SENSE
) ? "head" : "tail");
830 /* Kick off command processing */
831 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
835 static inline void maybe_release_dma_irq(struct Scsi_Host
*instance
)
837 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
839 /* Caller does the locking needed to set & test these data atomically */
840 if (list_empty(&hostdata
->disconnected
) &&
841 list_empty(&hostdata
->unissued
) &&
842 list_empty(&hostdata
->autosense
) &&
843 !hostdata
->connected
&&
844 !hostdata
->selecting
)
845 NCR5380_release_dma_irq(instance
);
849 * dequeue_next_cmd - dequeue a command for processing
850 * @instance: the scsi host instance
852 * Priority is given to commands on the autosense queue. These commands
853 * need autosense because of a CHECK CONDITION result.
855 * Returns a command pointer if a command is found for a target that is
856 * not already busy. Otherwise returns NULL.
859 static struct scsi_cmnd
*dequeue_next_cmd(struct Scsi_Host
*instance
)
861 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
862 struct NCR5380_cmd
*ncmd
;
863 struct scsi_cmnd
*cmd
;
865 if (list_empty(&hostdata
->autosense
)) {
866 list_for_each_entry(ncmd
, &hostdata
->unissued
, list
) {
867 cmd
= NCR5380_to_scmd(ncmd
);
868 dsprintk(NDEBUG_QUEUES
, instance
, "dequeue: cmd=%p target=%d busy=0x%02x lun=%llu\n",
869 cmd
, scmd_id(cmd
), hostdata
->busy
[scmd_id(cmd
)], cmd
->device
->lun
);
875 !(hostdata
->busy
[scmd_id(cmd
)] & (1 << cmd
->device
->lun
))
878 list_del(&ncmd
->list
);
879 dsprintk(NDEBUG_QUEUES
, instance
,
880 "dequeue: removed %p from issue queue\n", cmd
);
885 /* Autosense processing begins here */
886 ncmd
= list_first_entry(&hostdata
->autosense
,
887 struct NCR5380_cmd
, list
);
888 list_del(&ncmd
->list
);
889 cmd
= NCR5380_to_scmd(ncmd
);
890 dsprintk(NDEBUG_QUEUES
, instance
,
891 "dequeue: removed %p from autosense queue\n", cmd
);
892 scsi_eh_prep_cmnd(cmd
, &hostdata
->ses
, NULL
, 0, ~0);
893 hostdata
->sensing
= cmd
;
899 static void requeue_cmd(struct Scsi_Host
*instance
, struct scsi_cmnd
*cmd
)
901 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
902 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
904 if (hostdata
->sensing
) {
905 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
906 list_add(&ncmd
->list
, &hostdata
->autosense
);
907 hostdata
->sensing
= NULL
;
909 list_add(&ncmd
->list
, &hostdata
->unissued
);
913 * NCR5380_main - NCR state machines
915 * NCR5380_main is a coroutine that runs as long as more work can
916 * be done on the NCR5380 host adapters in a system. Both
917 * NCR5380_queue_command() and NCR5380_intr() will try to start it
918 * in case it is not running.
921 static void NCR5380_main(struct work_struct
*work
)
923 struct NCR5380_hostdata
*hostdata
=
924 container_of(work
, struct NCR5380_hostdata
, main_task
);
925 struct Scsi_Host
*instance
= hostdata
->host
;
926 struct scsi_cmnd
*cmd
;
930 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
931 * because also a timer int can trigger an abort or reset, which can
932 * alter queues and touch the Falcon lock.
938 spin_lock_irq(&hostdata
->lock
);
939 while (!hostdata
->connected
&&
940 (cmd
= dequeue_next_cmd(instance
))) {
942 dsprintk(NDEBUG_MAIN
, instance
, "main: dequeued %p\n", cmd
);
945 * Attempt to establish an I_T_L nexus here.
946 * On success, instance->hostdata->connected is set.
947 * On failure, we must add the command back to the
948 * issue queue so we can keep trying.
951 * REQUEST SENSE commands are issued without tagged
952 * queueing, even on SCSI-II devices because the
953 * contingent allegiance condition exists for the
956 /* ++roman: ...and the standard also requires that
957 * REQUEST SENSE command are untagged.
961 cmd_get_tag(cmd
, cmd
->cmnd
[0] != REQUEST_SENSE
);
963 cmd
= NCR5380_select(instance
, cmd
);
965 dsprintk(NDEBUG_MAIN
, instance
, "main: select complete\n");
966 maybe_release_dma_irq(instance
);
968 dsprintk(NDEBUG_MAIN
| NDEBUG_QUEUES
, instance
,
969 "main: select failed, returning %p to queue\n", cmd
);
970 requeue_cmd(instance
, cmd
);
976 if (hostdata
->connected
978 && !hostdata
->dma_len
981 dsprintk(NDEBUG_MAIN
, instance
, "main: performing information transfer\n");
982 NCR5380_information_transfer(instance
);
985 spin_unlock_irq(&hostdata
->lock
);
994 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
996 * Purpose : Called by interrupt handler when DMA finishes or a phase
997 * mismatch occurs (which would finish the DMA transfer).
999 * Inputs : instance - this instance of the NCR5380.
1002 static void NCR5380_dma_complete(struct Scsi_Host
*instance
)
1004 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1006 unsigned char **data
;
1008 int saved_data
= 0, overrun
= 0;
1011 if (hostdata
->read_overruns
) {
1012 p
= hostdata
->connected
->SCp
.phase
;
1015 if ((NCR5380_read(BUS_AND_STATUS_REG
) &
1016 (BASR_PHASE_MATCH
|BASR_ACK
)) ==
1017 (BASR_PHASE_MATCH
|BASR_ACK
)) {
1018 saved_data
= NCR5380_read(INPUT_DATA_REG
);
1020 dsprintk(NDEBUG_DMA
, instance
, "read overrun handled\n");
1025 #if defined(CONFIG_SUN3)
1026 if ((sun3scsi_dma_finish(rq_data_dir(hostdata
->connected
->request
)))) {
1027 pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n",
1032 /* make sure we're not stuck in a data phase */
1033 if ((NCR5380_read(BUS_AND_STATUS_REG
) & (BASR_PHASE_MATCH
| BASR_ACK
)) ==
1034 (BASR_PHASE_MATCH
| BASR_ACK
)) {
1035 pr_err("scsi%d: BASR %02x\n", instance
->host_no
,
1036 NCR5380_read(BUS_AND_STATUS_REG
));
1037 pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n",
1043 NCR5380_write(MODE_REG
, MR_BASE
);
1044 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1045 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1047 transferred
= hostdata
->dma_len
- NCR5380_dma_residual(instance
);
1048 hostdata
->dma_len
= 0;
1050 data
= (unsigned char **)&hostdata
->connected
->SCp
.ptr
;
1051 count
= &hostdata
->connected
->SCp
.this_residual
;
1052 *data
+= transferred
;
1053 *count
-= transferred
;
1055 if (hostdata
->read_overruns
) {
1058 if ((NCR5380_read(STATUS_REG
) & PHASE_MASK
) == p
&& (p
& SR_IO
)) {
1059 cnt
= toPIO
= hostdata
->read_overruns
;
1061 dprintk(NDEBUG_DMA
, "Got an input overrun, using saved byte\n");
1062 *(*data
)++ = saved_data
;
1067 dprintk(NDEBUG_DMA
, "Doing %d-byte PIO to 0x%08lx\n", cnt
, (long)*data
);
1068 NCR5380_transfer_pio(instance
, &p
, &cnt
, data
);
1069 *count
-= toPIO
- cnt
;
1073 #endif /* REAL_DMA */
1077 * NCR5380_intr - generic NCR5380 irq handler
1078 * @irq: interrupt number
1079 * @dev_id: device info
1081 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1082 * from the disconnected queue, and restarting NCR5380_main()
1085 * The chip can assert IRQ in any of six different conditions. The IRQ flag
1086 * is then cleared by reading the Reset Parity/Interrupt Register (RPIR).
1087 * Three of these six conditions are latched in the Bus and Status Register:
1088 * - End of DMA (cleared by ending DMA Mode)
1089 * - Parity error (cleared by reading RPIR)
1090 * - Loss of BSY (cleared by reading RPIR)
1091 * Two conditions have flag bits that are not latched:
1092 * - Bus phase mismatch (non-maskable in DMA Mode, cleared by ending DMA Mode)
1093 * - Bus reset (non-maskable)
1094 * The remaining condition has no flag bit at all:
1095 * - Selection/reselection
1097 * Hence, establishing the cause(s) of any interrupt is partly guesswork.
1098 * In "The DP8490 and DP5380 Comparison Guide", National Semiconductor
1099 * claimed that "the design of the [DP8490] interrupt logic ensures
1100 * interrupts will not be lost (they can be on the DP5380)."
1101 * The L5380/53C80 datasheet from LOGIC Devices has more details.
1103 * Checking for bus reset by reading RST is futile because of interrupt
1104 * latency, but a bus reset will reset chip logic. Checking for parity error
1105 * is unnecessary because that interrupt is never enabled. A Loss of BSY
1106 * condition will clear DMA Mode. We can tell when this occurs because the
1107 * the Busy Monitor interrupt is enabled together with DMA Mode.
1110 static irqreturn_t
NCR5380_intr(int irq
, void *dev_id
)
1112 struct Scsi_Host
*instance
= dev_id
;
1113 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1116 unsigned long flags
;
1118 spin_lock_irqsave(&hostdata
->lock
, flags
);
1120 basr
= NCR5380_read(BUS_AND_STATUS_REG
);
1121 if (basr
& BASR_IRQ
) {
1122 unsigned char mr
= NCR5380_read(MODE_REG
);
1123 unsigned char sr
= NCR5380_read(STATUS_REG
);
1125 dsprintk(NDEBUG_INTR
, instance
, "IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n",
1128 #if defined(REAL_DMA)
1129 if ((mr
& MR_DMA_MODE
) || (mr
& MR_MONITOR_BSY
)) {
1130 /* Probably End of DMA, Phase Mismatch or Loss of BSY.
1131 * We ack IRQ after clearing Mode Register. Workarounds
1132 * for End of DMA errata need to happen in DMA Mode.
1135 dsprintk(NDEBUG_INTR
, instance
, "interrupt in DMA mode\n");
1137 if (hostdata
->connected
) {
1138 NCR5380_dma_complete(instance
);
1139 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
1141 NCR5380_write(MODE_REG
, MR_BASE
);
1142 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1145 #endif /* REAL_DMA */
1146 if ((NCR5380_read(CURRENT_SCSI_DATA_REG
) & hostdata
->id_mask
) &&
1147 (sr
& (SR_SEL
| SR_IO
| SR_BSY
| SR_RST
)) == (SR_SEL
| SR_IO
)) {
1148 /* Probably reselected */
1149 NCR5380_write(SELECT_ENABLE_REG
, 0);
1150 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1152 dsprintk(NDEBUG_INTR
, instance
, "interrupt with SEL and IO\n");
1154 if (!hostdata
->connected
) {
1155 NCR5380_reselect(instance
);
1156 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
1158 if (!hostdata
->connected
)
1159 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1161 /* Probably Bus Reset */
1162 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1164 dsprintk(NDEBUG_INTR
, instance
, "unknown interrupt\n");
1165 #ifdef SUN3_SCSI_VME
1166 dregs
->csr
|= CSR_DMA_ENABLE
;
1171 shost_printk(KERN_NOTICE
, instance
, "interrupt without IRQ bit\n");
1172 #ifdef SUN3_SCSI_VME
1173 dregs
->csr
|= CSR_DMA_ENABLE
;
1177 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
1179 return IRQ_RETVAL(handled
);
1183 * Function : int NCR5380_select(struct Scsi_Host *instance,
1184 * struct scsi_cmnd *cmd)
1186 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1187 * including ARBITRATION, SELECTION, and initial message out for
1188 * IDENTIFY and queue messages.
1190 * Inputs : instance - instantiation of the 5380 driver on which this
1191 * target lives, cmd - SCSI command to execute.
1193 * Returns cmd if selection failed but should be retried,
1194 * NULL if selection failed and should not be retried, or
1195 * NULL if selection succeeded (hostdata->connected == cmd).
1198 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1199 * with registers as they should have been on entry - ie
1200 * SELECT_ENABLE will be set appropriately, the NCR5380
1201 * will cease to drive any SCSI bus signals.
1203 * If successful : I_T_L or I_T_L_Q nexus will be established,
1204 * instance->connected will be set to cmd.
1205 * SELECT interrupt will be disabled.
1207 * If failed (no target) : cmd->scsi_done() will be called, and the
1208 * cmd->result host byte set to DID_BAD_TARGET.
1211 static struct scsi_cmnd
*NCR5380_select(struct Scsi_Host
*instance
,
1212 struct scsi_cmnd
*cmd
)
1214 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1215 unsigned char tmp
[3], phase
;
1216 unsigned char *data
;
1220 NCR5380_dprint(NDEBUG_ARBITRATION
, instance
);
1221 dsprintk(NDEBUG_ARBITRATION
, instance
, "starting arbitration, id = %d\n",
1225 * Arbitration and selection phases are slow and involve dropping the
1226 * lock, so we have to watch out for EH. An exception handler may
1227 * change 'selecting' to NULL. This function will then return NULL
1228 * so that the caller will forget about 'cmd'. (During information
1229 * transfer phases, EH may change 'connected' to NULL.)
1231 hostdata
->selecting
= cmd
;
1234 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1235 * data bus during SELECTION.
1238 NCR5380_write(TARGET_COMMAND_REG
, 0);
1241 * Start arbitration.
1244 NCR5380_write(OUTPUT_DATA_REG
, hostdata
->id_mask
);
1245 NCR5380_write(MODE_REG
, MR_ARBITRATE
);
1247 /* The chip now waits for BUS FREE phase. Then after the 800 ns
1248 * Bus Free Delay, arbitration will begin.
1251 spin_unlock_irq(&hostdata
->lock
);
1252 err
= NCR5380_poll_politely2(instance
, MODE_REG
, MR_ARBITRATE
, 0,
1253 INITIATOR_COMMAND_REG
, ICR_ARBITRATION_PROGRESS
,
1254 ICR_ARBITRATION_PROGRESS
, HZ
);
1255 spin_lock_irq(&hostdata
->lock
);
1256 if (!(NCR5380_read(MODE_REG
) & MR_ARBITRATE
)) {
1257 /* Reselection interrupt */
1261 NCR5380_write(MODE_REG
, MR_BASE
);
1262 shost_printk(KERN_ERR
, instance
,
1263 "select: arbitration timeout\n");
1266 spin_unlock_irq(&hostdata
->lock
);
1268 /* The SCSI-2 arbitration delay is 2.4 us */
1271 /* Check for lost arbitration */
1272 if ((NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_LOST
) ||
1273 (NCR5380_read(CURRENT_SCSI_DATA_REG
) & hostdata
->id_higher_mask
) ||
1274 (NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_LOST
)) {
1275 NCR5380_write(MODE_REG
, MR_BASE
);
1276 dsprintk(NDEBUG_ARBITRATION
, instance
, "lost arbitration, deasserting MR_ARBITRATE\n");
1277 spin_lock_irq(&hostdata
->lock
);
1281 /* After/during arbitration, BSY should be asserted.
1282 * IBM DPES-31080 Version S31Q works now
1283 * Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman)
1285 NCR5380_write(INITIATOR_COMMAND_REG
,
1286 ICR_BASE
| ICR_ASSERT_SEL
| ICR_ASSERT_BSY
);
1289 * Again, bus clear + bus settle time is 1.2us, however, this is
1290 * a minimum so we'll udelay ceil(1.2)
1293 if (hostdata
->flags
& FLAG_TOSHIBA_DELAY
)
1298 spin_lock_irq(&hostdata
->lock
);
1300 /* NCR5380_reselect() clears MODE_REG after a reselection interrupt */
1301 if (!(NCR5380_read(MODE_REG
) & MR_ARBITRATE
))
1304 if (!hostdata
->selecting
) {
1305 NCR5380_write(MODE_REG
, MR_BASE
);
1306 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1310 dsprintk(NDEBUG_ARBITRATION
, instance
, "won arbitration\n");
1313 * Now that we have won arbitration, start Selection process, asserting
1314 * the host and target ID's on the SCSI bus.
1317 NCR5380_write(OUTPUT_DATA_REG
, hostdata
->id_mask
| (1 << scmd_id(cmd
)));
1320 * Raise ATN while SEL is true before BSY goes false from arbitration,
1321 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1322 * phase immediately after selection.
1325 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_BSY
|
1326 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
| ICR_ASSERT_SEL
);
1327 NCR5380_write(MODE_REG
, MR_BASE
);
1330 * Reselect interrupts must be turned off prior to the dropping of BSY,
1331 * otherwise we will trigger an interrupt.
1333 NCR5380_write(SELECT_ENABLE_REG
, 0);
1335 spin_unlock_irq(&hostdata
->lock
);
1338 * The initiator shall then wait at least two deskew delays and release
1341 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1344 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
|
1345 ICR_ASSERT_ATN
| ICR_ASSERT_SEL
);
1348 * Something weird happens when we cease to drive BSY - looks
1349 * like the board/chip is letting us do another read before the
1350 * appropriate propagation delay has expired, and we're confusing
1351 * a BSY signal from ourselves as the target's response to SELECTION.
1353 * A small delay (the 'C++' frontend breaks the pipeline with an
1354 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1355 * tighter 'C' code breaks and requires this) solves the problem -
1356 * the 1 us delay is arbitrary, and only used because this delay will
1357 * be the same on other platforms and since it works here, it should
1360 * wingel suggests that this could be due to failing to wait
1366 dsprintk(NDEBUG_SELECTION
, instance
, "selecting target %d\n", scmd_id(cmd
));
1369 * The SCSI specification calls for a 250 ms timeout for the actual
1373 err
= NCR5380_poll_politely(instance
, STATUS_REG
, SR_BSY
, SR_BSY
,
1374 msecs_to_jiffies(250));
1376 if ((NCR5380_read(STATUS_REG
) & (SR_SEL
| SR_IO
)) == (SR_SEL
| SR_IO
)) {
1377 spin_lock_irq(&hostdata
->lock
);
1378 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1379 NCR5380_reselect(instance
);
1380 if (!hostdata
->connected
)
1381 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1382 shost_printk(KERN_ERR
, instance
, "reselection after won arbitration?\n");
1387 spin_lock_irq(&hostdata
->lock
);
1388 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1389 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1390 /* Can't touch cmd if it has been reclaimed by the scsi ML */
1391 if (hostdata
->selecting
) {
1392 cmd
->result
= DID_BAD_TARGET
<< 16;
1393 complete_cmd(instance
, cmd
);
1394 dsprintk(NDEBUG_SELECTION
, instance
, "target did not respond within 250ms\n");
1401 * No less than two deskew delays after the initiator detects the
1402 * BSY signal is true, it shall release the SEL signal and may
1403 * change the DATA BUS. -wingel
1408 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1411 * Since we followed the SCSI spec, and raised ATN while SEL
1412 * was true but before BSY was false during selection, the information
1413 * transfer phase should be a MESSAGE OUT phase so that we can send the
1416 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1417 * message (2 bytes) with a tag ID that we increment with every command
1418 * until it wraps back to 0.
1420 * XXX - it turns out that there are some broken SCSI-II devices,
1421 * which claim to support tagged queuing but fail when more than
1422 * some number of commands are issued at once.
1425 /* Wait for start of REQ/ACK handshake */
1427 err
= NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, SR_REQ
, HZ
);
1428 spin_lock_irq(&hostdata
->lock
);
1430 shost_printk(KERN_ERR
, instance
, "select: REQ timeout\n");
1431 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1432 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1435 if (!hostdata
->selecting
) {
1440 dsprintk(NDEBUG_SELECTION
, instance
, "target %d selected, going into MESSAGE OUT phase.\n",
1442 tmp
[0] = IDENTIFY(1, cmd
->device
->lun
);
1445 if (cmd
->tag
!= TAG_NONE
) {
1446 tmp
[1] = hostdata
->last_message
= SIMPLE_QUEUE_TAG
;
1454 #endif /* SUPPORT_TAGS */
1456 /* Send message(s) */
1458 phase
= PHASE_MSGOUT
;
1459 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
1460 dsprintk(NDEBUG_SELECTION
, instance
, "nexus established.\n");
1461 /* XXX need to handle errors here */
1463 hostdata
->connected
= cmd
;
1464 #ifndef SUPPORT_TAGS
1465 hostdata
->busy
[cmd
->device
->id
] |= 1 << cmd
->device
->lun
;
1467 #ifdef SUN3_SCSI_VME
1468 dregs
->csr
|= CSR_INTR
;
1471 initialize_SCp(cmd
);
1476 if (!hostdata
->selecting
)
1478 hostdata
->selecting
= NULL
;
1483 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1484 * unsigned char *phase, int *count, unsigned char **data)
1486 * Purpose : transfers data in given phase using polled I/O
1488 * Inputs : instance - instance of driver, *phase - pointer to
1489 * what phase is expected, *count - pointer to number of
1490 * bytes to transfer, **data - pointer to data pointer.
1492 * Returns : -1 when different phase is entered without transferring
1493 * maximum number of bytes, 0 if all bytes are transferred or exit
1496 * Also, *phase, *count, *data are modified in place.
1498 * XXX Note : handling for bus free may be useful.
1502 * Note : this code is not as quick as it could be, however it
1503 * IS 100% reliable, and for the actual data transfer where speed
1504 * counts, we will always do a pseudo DMA or DMA transfer.
1507 static int NCR5380_transfer_pio(struct Scsi_Host
*instance
,
1508 unsigned char *phase
, int *count
,
1509 unsigned char **data
)
1511 unsigned char p
= *phase
, tmp
;
1513 unsigned char *d
= *data
;
1516 * The NCR5380 chip will only drive the SCSI bus when the
1517 * phase specified in the appropriate bits of the TARGET COMMAND
1518 * REGISTER match the STATUS REGISTER
1521 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1525 * Wait for assertion of REQ, after which the phase bits will be
1529 if (NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, SR_REQ
, HZ
) < 0)
1532 dsprintk(NDEBUG_HANDSHAKE
, instance
, "REQ asserted\n");
1534 /* Check for phase mismatch */
1535 if ((NCR5380_read(STATUS_REG
) & PHASE_MASK
) != p
) {
1536 dsprintk(NDEBUG_PIO
, instance
, "phase mismatch\n");
1537 NCR5380_dprint_phase(NDEBUG_PIO
, instance
);
1541 /* Do actual transfer from SCSI bus to / from memory */
1543 NCR5380_write(OUTPUT_DATA_REG
, *d
);
1545 *d
= NCR5380_read(CURRENT_SCSI_DATA_REG
);
1550 * The SCSI standard suggests that in MSGOUT phase, the initiator
1551 * should drop ATN on the last byte of the message phase
1552 * after REQ has been asserted for the handshake but before
1553 * the initiator raises ACK.
1557 if (!((p
& SR_MSG
) && c
> 1)) {
1558 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
);
1559 NCR5380_dprint(NDEBUG_PIO
, instance
);
1560 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1561 ICR_ASSERT_DATA
| ICR_ASSERT_ACK
);
1563 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1564 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
);
1565 NCR5380_dprint(NDEBUG_PIO
, instance
);
1566 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1567 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
| ICR_ASSERT_ACK
);
1570 NCR5380_dprint(NDEBUG_PIO
, instance
);
1571 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ACK
);
1574 if (NCR5380_poll_politely(instance
,
1575 STATUS_REG
, SR_REQ
, 0, 5 * HZ
) < 0)
1578 dsprintk(NDEBUG_HANDSHAKE
, instance
, "REQ negated, handshake complete\n");
1581 * We have several special cases to consider during REQ/ACK handshaking :
1582 * 1. We were in MSGOUT phase, and we are on the last byte of the
1583 * message. ATN must be dropped as ACK is dropped.
1585 * 2. We are in a MSGIN phase, and we are on the last byte of the
1586 * message. We must exit with ACK asserted, so that the calling
1587 * code may raise ATN before dropping ACK to reject the message.
1589 * 3. ACK and ATN are clear and the target may proceed as normal.
1591 if (!(p
== PHASE_MSGIN
&& c
== 1)) {
1592 if (p
== PHASE_MSGOUT
&& c
> 1)
1593 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1595 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1599 dsprintk(NDEBUG_PIO
, instance
, "residual %d\n", c
);
1603 tmp
= NCR5380_read(STATUS_REG
);
1604 /* The phase read from the bus is valid if either REQ is (already)
1605 * asserted or if ACK hasn't been released yet. The latter applies if
1606 * we're in MSG IN, DATA IN or STATUS and all bytes have been received.
1608 if ((tmp
& SR_REQ
) || ((tmp
& SR_IO
) && c
== 0))
1609 *phase
= tmp
& PHASE_MASK
;
1611 *phase
= PHASE_UNKNOWN
;
1613 if (!c
|| (*phase
== p
))
1620 * do_reset - issue a reset command
1621 * @instance: adapter to reset
1623 * Issue a reset sequence to the NCR5380 and try and get the bus
1624 * back into sane shape.
1626 * This clears the reset interrupt flag because there may be no handler for
1627 * it. When the driver is initialized, the NCR5380_intr() handler has not yet
1628 * been installed. And when in EH we may have released the ST DMA interrupt.
1631 static void do_reset(struct Scsi_Host
*instance
)
1633 unsigned long flags
;
1635 local_irq_save(flags
);
1636 NCR5380_write(TARGET_COMMAND_REG
,
1637 PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG
) & PHASE_MASK
));
1638 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_RST
);
1640 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1641 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1642 local_irq_restore(flags
);
1646 * do_abort - abort the currently established nexus by going to
1647 * MESSAGE OUT phase and sending an ABORT message.
1648 * @instance: relevant scsi host instance
1650 * Returns 0 on success, -1 on failure.
1653 static int do_abort(struct Scsi_Host
*instance
)
1655 unsigned char *msgptr
, phase
, tmp
;
1659 /* Request message out phase */
1660 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1663 * Wait for the target to indicate a valid phase by asserting
1664 * REQ. Once this happens, we'll have either a MSGOUT phase
1665 * and can immediately send the ABORT message, or we'll have some
1666 * other phase and will have to source/sink data.
1668 * We really don't care what value was on the bus or what value
1669 * the target sees, so we just handshake.
1672 rc
= NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, SR_REQ
, 10 * HZ
);
1676 tmp
= NCR5380_read(STATUS_REG
) & PHASE_MASK
;
1678 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(tmp
));
1680 if (tmp
!= PHASE_MSGOUT
) {
1681 NCR5380_write(INITIATOR_COMMAND_REG
,
1682 ICR_BASE
| ICR_ASSERT_ATN
| ICR_ASSERT_ACK
);
1683 rc
= NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, 0, 3 * HZ
);
1686 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1692 phase
= PHASE_MSGOUT
;
1693 NCR5380_transfer_pio(instance
, &phase
, &len
, &msgptr
);
1696 * If we got here, and the command completed successfully,
1697 * we're about to go into bus free state.
1700 return len
? -1 : 0;
1703 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1707 #if defined(REAL_DMA)
1709 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1710 * unsigned char *phase, int *count, unsigned char **data)
1712 * Purpose : transfers data in given phase using either real
1715 * Inputs : instance - instance of driver, *phase - pointer to
1716 * what phase is expected, *count - pointer to number of
1717 * bytes to transfer, **data - pointer to data pointer.
1719 * Returns : -1 when different phase is entered without transferring
1720 * maximum number of bytes, 0 if all bytes or transferred or exit
1723 * Also, *phase, *count, *data are modified in place.
1727 static int NCR5380_transfer_dma(struct Scsi_Host
*instance
,
1728 unsigned char *phase
, int *count
,
1729 unsigned char **data
)
1731 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1732 register int c
= *count
;
1733 register unsigned char p
= *phase
;
1735 #if defined(CONFIG_SUN3)
1737 if (!sun3_dma_setup_done
) {
1738 pr_err("scsi%d: transfer_dma without setup!\n",
1742 hostdata
->dma_len
= c
;
1744 dsprintk(NDEBUG_DMA
, instance
, "initializing DMA %s: length %d, address %p\n",
1745 (p
& SR_IO
) ? "receive" : "send", c
, *data
);
1747 /* netbsd turns off ints here, why not be safe and do it too */
1749 /* send start chain */
1750 sun3scsi_dma_start(c
, *data
);
1752 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1753 NCR5380_write(MODE_REG
, MR_BASE
| MR_DMA_MODE
| MR_MONITOR_BSY
|
1754 MR_ENABLE_EOP_INTR
);
1756 NCR5380_write(INITIATOR_COMMAND_REG
, 0);
1757 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG
, 0);
1759 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_ASSERT_DATA
);
1760 NCR5380_write(START_DMA_SEND_REG
, 0);
1763 #ifdef SUN3_SCSI_VME
1764 dregs
->csr
|= CSR_DMA_ENABLE
;
1767 sun3_dma_active
= 1;
1769 #else /* !defined(CONFIG_SUN3) */
1770 register unsigned char *d
= *data
;
1773 if ((tmp
= (NCR5380_read(STATUS_REG
) & PHASE_MASK
)) != p
) {
1778 if (hostdata
->read_overruns
&& (p
& SR_IO
))
1779 c
-= hostdata
->read_overruns
;
1781 dsprintk(NDEBUG_DMA
, instance
, "initializing DMA %s: length %d, address %p\n",
1782 (p
& SR_IO
) ? "receive" : "send", c
, d
);
1784 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1785 NCR5380_write(MODE_REG
, MR_BASE
| MR_DMA_MODE
| MR_MONITOR_BSY
|
1786 MR_ENABLE_EOP_INTR
);
1788 if (!(hostdata
->flags
& FLAG_LATE_DMA_SETUP
)) {
1789 /* On the Medusa, it is a must to initialize the DMA before
1790 * starting the NCR. This is also the cleaner way for the TT.
1792 hostdata
->dma_len
= (p
& SR_IO
) ?
1793 NCR5380_dma_read_setup(instance
, d
, c
) :
1794 NCR5380_dma_write_setup(instance
, d
, c
);
1798 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG
, 0);
1800 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
);
1801 NCR5380_write(START_DMA_SEND_REG
, 0);
1804 if (hostdata
->flags
& FLAG_LATE_DMA_SETUP
) {
1805 /* On the Falcon, the DMA setup must be done after the last */
1806 /* NCR access, else the DMA setup gets trashed!
1808 hostdata
->dma_len
= (p
& SR_IO
) ?
1809 NCR5380_dma_read_setup(instance
, d
, c
) :
1810 NCR5380_dma_write_setup(instance
, d
, c
);
1812 #endif /* !defined(CONFIG_SUN3) */
1816 #endif /* defined(REAL_DMA) */
1819 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1821 * Purpose : run through the various SCSI phases and do as the target
1822 * directs us to. Operates on the currently connected command,
1823 * instance->connected.
1825 * Inputs : instance, instance for which we are doing commands
1827 * Side effects : SCSI things happen, the disconnected queue will be
1828 * modified if a command disconnects, *instance->connected will
1831 * XXX Note : we need to watch for bus free or a reset condition here
1832 * to recover from an unexpected bus free condition.
1835 static void NCR5380_information_transfer(struct Scsi_Host
*instance
)
1837 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1838 unsigned char msgout
= NOP
;
1841 #if defined(REAL_DMA)
1844 unsigned char *data
;
1845 unsigned char phase
, tmp
, extended_msg
[10], old_phase
= 0xff;
1846 struct scsi_cmnd
*cmd
;
1848 #ifdef SUN3_SCSI_VME
1849 dregs
->csr
|= CSR_INTR
;
1852 while ((cmd
= hostdata
->connected
)) {
1853 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
1855 tmp
= NCR5380_read(STATUS_REG
);
1856 /* We only have a valid SCSI phase when REQ is asserted */
1858 phase
= (tmp
& PHASE_MASK
);
1859 if (phase
!= old_phase
) {
1861 NCR5380_dprint_phase(NDEBUG_INFORMATION
, instance
);
1863 #if defined(CONFIG_SUN3)
1864 if (phase
== PHASE_CMDOUT
) {
1865 #if defined(REAL_DMA)
1867 unsigned long count
;
1869 if (!cmd
->SCp
.this_residual
&& cmd
->SCp
.buffers_residual
) {
1870 count
= cmd
->SCp
.buffer
->length
;
1871 d
= sg_virt(cmd
->SCp
.buffer
);
1873 count
= cmd
->SCp
.this_residual
;
1876 /* this command setup for dma yet? */
1877 if ((count
>= DMA_MIN_SIZE
) && (sun3_dma_setup_done
!= cmd
)) {
1878 if (cmd
->request
->cmd_type
== REQ_TYPE_FS
) {
1879 sun3scsi_dma_setup(instance
, d
, count
,
1880 rq_data_dir(cmd
->request
));
1881 sun3_dma_setup_done
= cmd
;
1885 #ifdef SUN3_SCSI_VME
1886 dregs
->csr
|= CSR_INTR
;
1889 #endif /* CONFIG_SUN3 */
1891 if (sink
&& (phase
!= PHASE_MSGOUT
)) {
1892 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(tmp
));
1894 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
|
1896 while (NCR5380_read(STATUS_REG
) & SR_REQ
)
1898 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1906 #if (NDEBUG & NDEBUG_NO_DATAOUT)
1907 shost_printk(KERN_DEBUG
, instance
, "NDEBUG_NO_DATAOUT set, attempted DATAOUT aborted\n");
1910 cmd
->result
= DID_ERROR
<< 16;
1911 complete_cmd(instance
, cmd
);
1916 * If there is no room left in the current buffer in the
1917 * scatter-gather list, move onto the next one.
1920 if (!cmd
->SCp
.this_residual
&& cmd
->SCp
.buffers_residual
) {
1922 --cmd
->SCp
.buffers_residual
;
1923 cmd
->SCp
.this_residual
= cmd
->SCp
.buffer
->length
;
1924 cmd
->SCp
.ptr
= sg_virt(cmd
->SCp
.buffer
);
1925 merge_contiguous_buffers(cmd
);
1926 dsprintk(NDEBUG_INFORMATION
, instance
, "%d bytes and %d buffers left\n",
1927 cmd
->SCp
.this_residual
,
1928 cmd
->SCp
.buffers_residual
);
1932 * The preferred transfer method is going to be
1933 * PSEUDO-DMA for systems that are strictly PIO,
1934 * since we can let the hardware do the handshaking.
1936 * For this to work, we need to know the transfersize
1937 * ahead of time, since the pseudo-DMA code will sit
1938 * in an unconditional loop.
1941 /* ++roman: I suggest, this should be
1943 * instead of leaving REAL_DMA out.
1946 #if defined(REAL_DMA)
1947 #if !defined(CONFIG_SUN3)
1949 if (!cmd
->device
->borken
)
1951 transfersize
= NCR5380_dma_xfer_len(instance
, cmd
, phase
);
1953 if (transfersize
>= DMA_MIN_SIZE
) {
1955 cmd
->SCp
.phase
= phase
;
1956 if (NCR5380_transfer_dma(instance
, &phase
,
1957 &len
, (unsigned char **)&cmd
->SCp
.ptr
)) {
1959 * If the watchdog timer fires, all future
1960 * accesses to this device will use the
1963 scmd_printk(KERN_INFO
, cmd
,
1964 "switching to slow handshake\n");
1965 cmd
->device
->borken
= 1;
1968 cmd
->result
= DID_ERROR
<< 16;
1969 complete_cmd(instance
, cmd
);
1970 /* XXX - need to source or sink data here, as appropriate */
1973 /* ++roman: When using real DMA,
1974 * information_transfer() should return after
1975 * starting DMA since it has nothing more to
1980 cmd
->SCp
.this_residual
-= transfersize
- len
;
1984 #endif /* defined(REAL_DMA) */
1986 spin_unlock_irq(&hostdata
->lock
);
1987 NCR5380_transfer_pio(instance
, &phase
,
1988 (int *)&cmd
->SCp
.this_residual
,
1989 (unsigned char **)&cmd
->SCp
.ptr
);
1990 spin_lock_irq(&hostdata
->lock
);
1992 #if defined(CONFIG_SUN3) && defined(REAL_DMA)
1993 /* if we had intended to dma that command clear it */
1994 if (sun3_dma_setup_done
== cmd
)
1995 sun3_dma_setup_done
= NULL
;
2001 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2002 cmd
->SCp
.Message
= tmp
;
2006 case COMMAND_COMPLETE
:
2007 /* Accept message by clearing ACK */
2008 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2009 dsprintk(NDEBUG_QUEUES
, instance
,
2010 "COMMAND COMPLETE %p target %d lun %llu\n",
2011 cmd
, scmd_id(cmd
), cmd
->device
->lun
);
2013 hostdata
->connected
= NULL
;
2016 if (status_byte(cmd
->SCp
.Status
) == QUEUE_FULL
) {
2017 u8 lun
= cmd
->device
->lun
;
2018 struct tag_alloc
*ta
= &hostdata
->TagAlloc
[scmd_id(cmd
)][lun
];
2020 dsprintk(NDEBUG_TAGS
, instance
,
2021 "QUEUE_FULL %p target %d lun %d nr_allocated %d\n",
2022 cmd
, scmd_id(cmd
), lun
, ta
->nr_allocated
);
2023 if (ta
->queue_size
> ta
->nr_allocated
)
2024 ta
->queue_size
= ta
->nr_allocated
;
2028 cmd
->result
&= ~0xffff;
2029 cmd
->result
|= cmd
->SCp
.Status
;
2030 cmd
->result
|= cmd
->SCp
.Message
<< 8;
2032 if (cmd
->cmnd
[0] == REQUEST_SENSE
)
2033 complete_cmd(instance
, cmd
);
2035 if (cmd
->SCp
.Status
== SAM_STAT_CHECK_CONDITION
||
2036 cmd
->SCp
.Status
== SAM_STAT_COMMAND_TERMINATED
) {
2037 dsprintk(NDEBUG_QUEUES
, instance
, "autosense: adding cmd %p to tail of autosense queue\n",
2039 list_add_tail(&ncmd
->list
,
2040 &hostdata
->autosense
);
2042 complete_cmd(instance
, cmd
);
2046 * Restore phase bits to 0 so an interrupted selection,
2047 * arbitration can resume.
2049 NCR5380_write(TARGET_COMMAND_REG
, 0);
2051 /* Enable reselect interrupts */
2052 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2054 maybe_release_dma_irq(instance
);
2056 case MESSAGE_REJECT
:
2057 /* Accept message by clearing ACK */
2058 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2059 switch (hostdata
->last_message
) {
2060 case HEAD_OF_QUEUE_TAG
:
2061 case ORDERED_QUEUE_TAG
:
2062 case SIMPLE_QUEUE_TAG
:
2063 /* The target obviously doesn't support tagged
2064 * queuing, even though it announced this ability in
2065 * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2066 * clear 'tagged_supported' and lock the LUN, since
2067 * the command is treated as untagged further on.
2069 cmd
->device
->tagged_supported
= 0;
2070 hostdata
->busy
[cmd
->device
->id
] |= (1 << cmd
->device
->lun
);
2071 cmd
->tag
= TAG_NONE
;
2072 dsprintk(NDEBUG_TAGS
, instance
, "target %d lun %llu rejected QUEUE_TAG message; tagged queuing disabled\n",
2073 scmd_id(cmd
), cmd
->device
->lun
);
2078 /* Accept message by clearing ACK */
2079 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2080 hostdata
->connected
= NULL
;
2081 list_add(&ncmd
->list
, &hostdata
->disconnected
);
2082 dsprintk(NDEBUG_INFORMATION
| NDEBUG_QUEUES
,
2083 instance
, "connected command %p for target %d lun %llu moved to disconnected queue\n",
2084 cmd
, scmd_id(cmd
), cmd
->device
->lun
);
2087 * Restore phase bits to 0 so an interrupted selection,
2088 * arbitration can resume.
2090 NCR5380_write(TARGET_COMMAND_REG
, 0);
2092 /* Enable reselect interrupts */
2093 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2094 #ifdef SUN3_SCSI_VME
2095 dregs
->csr
|= CSR_DMA_ENABLE
;
2099 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2100 * operation, in violation of the SCSI spec so we can safely
2101 * ignore SAVE/RESTORE pointers calls.
2103 * Unfortunately, some disks violate the SCSI spec and
2104 * don't issue the required SAVE_POINTERS message before
2105 * disconnecting, and we have to break spec to remain
2109 case RESTORE_POINTERS
:
2110 /* Accept message by clearing ACK */
2111 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2113 case EXTENDED_MESSAGE
:
2115 * Start the message buffer with the EXTENDED_MESSAGE
2116 * byte, since spi_print_msg() wants the whole thing.
2118 extended_msg
[0] = EXTENDED_MESSAGE
;
2119 /* Accept first byte by clearing ACK */
2120 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2122 spin_unlock_irq(&hostdata
->lock
);
2124 dsprintk(NDEBUG_EXTENDED
, instance
, "receiving extended message\n");
2127 data
= extended_msg
+ 1;
2128 phase
= PHASE_MSGIN
;
2129 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2130 dsprintk(NDEBUG_EXTENDED
, instance
, "length %d, code 0x%02x\n",
2131 (int)extended_msg
[1],
2132 (int)extended_msg
[2]);
2134 if (!len
&& extended_msg
[1] > 0 &&
2135 extended_msg
[1] <= sizeof(extended_msg
) - 2) {
2136 /* Accept third byte by clearing ACK */
2137 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2138 len
= extended_msg
[1] - 1;
2139 data
= extended_msg
+ 3;
2140 phase
= PHASE_MSGIN
;
2142 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2143 dsprintk(NDEBUG_EXTENDED
, instance
, "message received, residual %d\n",
2146 switch (extended_msg
[2]) {
2149 case EXTENDED_MODIFY_DATA_POINTER
:
2150 case EXTENDED_EXTENDED_IDENTIFY
:
2154 shost_printk(KERN_ERR
, instance
, "error receiving extended message\n");
2157 shost_printk(KERN_NOTICE
, instance
, "extended message code %02x length %d is too long\n",
2158 extended_msg
[2], extended_msg
[1]);
2162 spin_lock_irq(&hostdata
->lock
);
2163 if (!hostdata
->connected
)
2166 /* Fall through to reject message */
2169 * If we get something weird that we aren't expecting,
2174 shost_printk(KERN_ERR
, instance
, "rejecting message ");
2175 spi_print_msg(extended_msg
);
2177 } else if (tmp
!= EXTENDED_MESSAGE
)
2178 scmd_printk(KERN_INFO
, cmd
,
2179 "rejecting unknown message %02x\n",
2182 scmd_printk(KERN_INFO
, cmd
,
2183 "rejecting unknown extended message code %02x, length %d\n",
2184 extended_msg
[1], extended_msg
[0]);
2186 msgout
= MESSAGE_REJECT
;
2187 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
2189 } /* switch (tmp) */
2194 hostdata
->last_message
= msgout
;
2195 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2196 if (msgout
== ABORT
) {
2197 hostdata
->connected
= NULL
;
2198 cmd
->result
= DID_ERROR
<< 16;
2199 complete_cmd(instance
, cmd
);
2200 maybe_release_dma_irq(instance
);
2201 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2210 * XXX for performance reasons, on machines with a
2211 * PSEUDO-DMA architecture we should probably
2212 * use the dma transfer function.
2214 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2219 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2220 cmd
->SCp
.Status
= tmp
;
2223 shost_printk(KERN_ERR
, instance
, "unknown phase\n");
2224 NCR5380_dprint(NDEBUG_ANY
, instance
);
2225 } /* switch(phase) */
2227 spin_unlock_irq(&hostdata
->lock
);
2228 NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, SR_REQ
, HZ
);
2229 spin_lock_irq(&hostdata
->lock
);
2235 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2237 * Purpose : does reselection, initializing the instance->connected
2238 * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
2239 * nexus has been reestablished,
2241 * Inputs : instance - this instance of the NCR5380.
2245 /* it might eventually prove necessary to do a dma setup on
2246 reselection, but it doesn't seem to be needed now -- sam */
2248 static void NCR5380_reselect(struct Scsi_Host
*instance
)
2250 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
2251 unsigned char target_mask
;
2256 unsigned char msg
[3];
2257 int __maybe_unused len
;
2258 unsigned char __maybe_unused
*data
, __maybe_unused phase
;
2259 struct NCR5380_cmd
*ncmd
;
2260 struct scsi_cmnd
*tmp
;
2263 * Disable arbitration, etc. since the host adapter obviously
2264 * lost, and tell an interrupted NCR5380_select() to restart.
2267 NCR5380_write(MODE_REG
, MR_BASE
);
2269 target_mask
= NCR5380_read(CURRENT_SCSI_DATA_REG
) & ~(hostdata
->id_mask
);
2271 dsprintk(NDEBUG_RESELECTION
, instance
, "reselect\n");
2274 * At this point, we have detected that our SCSI ID is on the bus,
2275 * SEL is true and BSY was false for at least one bus settle delay
2278 * We must assert BSY ourselves, until the target drops the SEL
2282 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_BSY
);
2283 if (NCR5380_poll_politely(instance
,
2284 STATUS_REG
, SR_SEL
, 0, 2 * HZ
) < 0) {
2285 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2288 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2291 * Wait for target to go into MSGIN.
2294 if (NCR5380_poll_politely(instance
,
2295 STATUS_REG
, SR_REQ
, SR_REQ
, 2 * HZ
) < 0) {
2300 #if defined(CONFIG_SUN3) && defined(REAL_DMA)
2301 /* acknowledge toggle to MSGIN */
2302 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(PHASE_MSGIN
));
2304 /* peek at the byte without really hitting the bus */
2305 msg
[0] = NCR5380_read(CURRENT_SCSI_DATA_REG
);
2309 phase
= PHASE_MSGIN
;
2310 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2318 if (!(msg
[0] & 0x80)) {
2319 shost_printk(KERN_ERR
, instance
, "expecting IDENTIFY message, got ");
2325 lun
= msg
[0] & 0x07;
2327 #if defined(SUPPORT_TAGS) && !defined(CONFIG_SUN3)
2328 /* If the phase is still MSGIN, the target wants to send some more
2329 * messages. In case it supports tagged queuing, this is probably a
2330 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2333 if (phase
== PHASE_MSGIN
&& (hostdata
->flags
& FLAG_TAGGED_QUEUING
)) {
2334 /* Accept previous IDENTIFY message by clearing ACK */
2335 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2338 if (!NCR5380_transfer_pio(instance
, &phase
, &len
, &data
) &&
2339 msg
[1] == SIMPLE_QUEUE_TAG
)
2341 dsprintk(NDEBUG_TAGS
, instance
, "reselect: target mask %02x, lun %d sent tag %d\n",
2342 target_mask
, lun
, tag
);
2347 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2348 * just reestablished, and remove it from the disconnected queue.
2352 list_for_each_entry(ncmd
, &hostdata
->disconnected
, list
) {
2353 struct scsi_cmnd
*cmd
= NCR5380_to_scmd(ncmd
);
2355 if (target_mask
== (1 << scmd_id(cmd
)) &&
2356 lun
== (u8
)cmd
->device
->lun
2358 && (tag
== cmd
->tag
)
2361 list_del(&ncmd
->list
);
2368 dsprintk(NDEBUG_RESELECTION
| NDEBUG_QUEUES
, instance
,
2369 "reselect: removed %p from disconnected queue\n", tmp
);
2373 shost_printk(KERN_ERR
, instance
, "target bitmask 0x%02x lun %d tag %d not in disconnected queue.\n",
2374 target_mask
, lun
, tag
);
2376 shost_printk(KERN_ERR
, instance
, "target bitmask 0x%02x lun %d not in disconnected queue.\n",
2380 * Since we have an established nexus that we can't do anything
2381 * with, we must abort it.
2387 #if defined(CONFIG_SUN3) && defined(REAL_DMA)
2388 /* engage dma setup for the command we just saw */
2391 unsigned long count
;
2393 if (!tmp
->SCp
.this_residual
&& tmp
->SCp
.buffers_residual
) {
2394 count
= tmp
->SCp
.buffer
->length
;
2395 d
= sg_virt(tmp
->SCp
.buffer
);
2397 count
= tmp
->SCp
.this_residual
;
2400 /* setup this command for dma if not already */
2401 if ((count
>= DMA_MIN_SIZE
) && (sun3_dma_setup_done
!= tmp
)) {
2402 sun3scsi_dma_setup(instance
, d
, count
,
2403 rq_data_dir(tmp
->request
));
2404 sun3_dma_setup_done
= tmp
;
2408 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ACK
);
2411 /* Accept message by clearing ACK */
2412 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2414 #if defined(SUPPORT_TAGS) && defined(CONFIG_SUN3)
2415 /* If the phase is still MSGIN, the target wants to send some more
2416 * messages. In case it supports tagged queuing, this is probably a
2417 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2420 if (phase
== PHASE_MSGIN
&& setup_use_tagged_queuing
) {
2421 /* Accept previous IDENTIFY message by clearing ACK */
2422 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2425 if (!NCR5380_transfer_pio(instance
, &phase
, &len
, &data
) &&
2426 msg
[1] == SIMPLE_QUEUE_TAG
)
2428 dsprintk(NDEBUG_TAGS
, instance
, "reselect: target mask %02x, lun %d sent tag %d\n"
2429 target_mask
, lun
, tag
);
2433 hostdata
->connected
= tmp
;
2434 dsprintk(NDEBUG_RESELECTION
, instance
, "nexus established, target %d, lun %llu, tag %d\n",
2435 scmd_id(tmp
), tmp
->device
->lun
, tmp
->tag
);
2440 * list_find_cmd - test for presence of a command in a linked list
2441 * @haystack: list of commands
2442 * @needle: command to search for
2445 static bool list_find_cmd(struct list_head
*haystack
,
2446 struct scsi_cmnd
*needle
)
2448 struct NCR5380_cmd
*ncmd
;
2450 list_for_each_entry(ncmd
, haystack
, list
)
2451 if (NCR5380_to_scmd(ncmd
) == needle
)
2457 * list_remove_cmd - remove a command from linked list
2458 * @haystack: list of commands
2459 * @needle: command to remove
2462 static bool list_del_cmd(struct list_head
*haystack
,
2463 struct scsi_cmnd
*needle
)
2465 if (list_find_cmd(haystack
, needle
)) {
2466 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(needle
);
2468 list_del(&ncmd
->list
);
2475 * NCR5380_abort - scsi host eh_abort_handler() method
2476 * @cmd: the command to be aborted
2478 * Try to abort a given command by removing it from queues and/or sending
2479 * the target an abort message. This may not succeed in causing a target
2480 * to abort the command. Nonetheless, the low-level driver must forget about
2481 * the command because the mid-layer reclaims it and it may be re-issued.
2483 * The normal path taken by a command is as follows. For EH we trace this
2484 * same path to locate and abort the command.
2486 * unissued -> selecting -> [unissued -> selecting ->]... connected ->
2487 * [disconnected -> connected ->]...
2488 * [autosense -> connected ->] done
2490 * If cmd is unissued then just remove it.
2491 * If cmd is disconnected, try to select the target.
2492 * If cmd is connected, try to send an abort message.
2493 * If cmd is waiting for autosense, give it a chance to complete but check
2494 * that it isn't left connected.
2495 * If cmd was not found at all then presumably it has already been completed,
2496 * in which case return SUCCESS to try to avoid further EH measures.
2497 * If the command has not completed yet, we must not fail to find it.
2500 static int NCR5380_abort(struct scsi_cmnd
*cmd
)
2502 struct Scsi_Host
*instance
= cmd
->device
->host
;
2503 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
2504 unsigned long flags
;
2505 int result
= SUCCESS
;
2507 spin_lock_irqsave(&hostdata
->lock
, flags
);
2509 #if (NDEBUG & NDEBUG_ANY)
2510 scmd_printk(KERN_INFO
, cmd
, __func__
);
2512 NCR5380_dprint(NDEBUG_ANY
, instance
);
2513 NCR5380_dprint_phase(NDEBUG_ANY
, instance
);
2515 if (list_del_cmd(&hostdata
->unissued
, cmd
)) {
2516 dsprintk(NDEBUG_ABORT
, instance
,
2517 "abort: removed %p from issue queue\n", cmd
);
2518 cmd
->result
= DID_ABORT
<< 16;
2519 cmd
->scsi_done(cmd
); /* No tag or busy flag to worry about */
2522 if (hostdata
->selecting
== cmd
) {
2523 dsprintk(NDEBUG_ABORT
, instance
,
2524 "abort: cmd %p == selecting\n", cmd
);
2525 hostdata
->selecting
= NULL
;
2526 cmd
->result
= DID_ABORT
<< 16;
2527 complete_cmd(instance
, cmd
);
2531 if (list_del_cmd(&hostdata
->disconnected
, cmd
)) {
2532 dsprintk(NDEBUG_ABORT
, instance
,
2533 "abort: removed %p from disconnected list\n", cmd
);
2534 cmd
->result
= DID_ERROR
<< 16;
2535 if (!hostdata
->connected
)
2536 NCR5380_select(instance
, cmd
);
2537 if (hostdata
->connected
!= cmd
) {
2538 complete_cmd(instance
, cmd
);
2544 if (hostdata
->connected
== cmd
) {
2545 dsprintk(NDEBUG_ABORT
, instance
, "abort: cmd %p is connected\n", cmd
);
2546 hostdata
->connected
= NULL
;
2547 if (do_abort(instance
)) {
2548 set_host_byte(cmd
, DID_ERROR
);
2549 complete_cmd(instance
, cmd
);
2553 set_host_byte(cmd
, DID_ABORT
);
2555 hostdata
->dma_len
= 0;
2557 if (cmd
->cmnd
[0] == REQUEST_SENSE
)
2558 complete_cmd(instance
, cmd
);
2560 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
2562 /* Perform autosense for this command */
2563 list_add(&ncmd
->list
, &hostdata
->autosense
);
2567 if (list_find_cmd(&hostdata
->autosense
, cmd
)) {
2568 dsprintk(NDEBUG_ABORT
, instance
,
2569 "abort: found %p on sense queue\n", cmd
);
2570 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
2571 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
2573 spin_lock_irqsave(&hostdata
->lock
, flags
);
2574 if (list_del_cmd(&hostdata
->autosense
, cmd
)) {
2575 dsprintk(NDEBUG_ABORT
, instance
,
2576 "abort: removed %p from sense queue\n", cmd
);
2577 set_host_byte(cmd
, DID_ABORT
);
2578 complete_cmd(instance
, cmd
);
2583 if (hostdata
->connected
== cmd
) {
2584 dsprintk(NDEBUG_ABORT
, instance
, "abort: cmd %p is connected\n", cmd
);
2585 hostdata
->connected
= NULL
;
2586 if (do_abort(instance
)) {
2587 set_host_byte(cmd
, DID_ERROR
);
2588 complete_cmd(instance
, cmd
);
2592 set_host_byte(cmd
, DID_ABORT
);
2594 hostdata
->dma_len
= 0;
2596 complete_cmd(instance
, cmd
);
2600 if (result
== FAILED
)
2601 dsprintk(NDEBUG_ABORT
, instance
, "abort: failed to abort %p\n", cmd
);
2603 dsprintk(NDEBUG_ABORT
, instance
, "abort: successfully aborted %p\n", cmd
);
2605 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
2606 maybe_release_dma_irq(instance
);
2607 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
2614 * NCR5380_bus_reset - reset the SCSI bus
2615 * @cmd: SCSI command undergoing EH
2620 static int NCR5380_bus_reset(struct scsi_cmnd
*cmd
)
2622 struct Scsi_Host
*instance
= cmd
->device
->host
;
2623 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
2625 unsigned long flags
;
2626 struct NCR5380_cmd
*ncmd
;
2628 spin_lock_irqsave(&hostdata
->lock
, flags
);
2630 #if (NDEBUG & NDEBUG_ANY)
2631 scmd_printk(KERN_INFO
, cmd
, __func__
);
2633 NCR5380_dprint(NDEBUG_ANY
, instance
);
2634 NCR5380_dprint_phase(NDEBUG_ANY
, instance
);
2638 /* reset NCR registers */
2639 NCR5380_write(MODE_REG
, MR_BASE
);
2640 NCR5380_write(TARGET_COMMAND_REG
, 0);
2641 NCR5380_write(SELECT_ENABLE_REG
, 0);
2643 /* After the reset, there are no more connected or disconnected commands
2644 * and no busy units; so clear the low-level status here to avoid
2645 * conflicts when the mid-level code tries to wake up the affected
2649 hostdata
->selecting
= NULL
;
2651 list_for_each_entry(ncmd
, &hostdata
->disconnected
, list
) {
2652 struct scsi_cmnd
*cmd
= NCR5380_to_scmd(ncmd
);
2654 set_host_byte(cmd
, DID_RESET
);
2655 cmd
->scsi_done(cmd
);
2658 list_for_each_entry(ncmd
, &hostdata
->autosense
, list
) {
2659 struct scsi_cmnd
*cmd
= NCR5380_to_scmd(ncmd
);
2661 set_host_byte(cmd
, DID_RESET
);
2662 cmd
->scsi_done(cmd
);
2665 if (hostdata
->connected
) {
2666 set_host_byte(hostdata
->connected
, DID_RESET
);
2667 complete_cmd(instance
, hostdata
->connected
);
2668 hostdata
->connected
= NULL
;
2671 if (hostdata
->sensing
) {
2672 set_host_byte(hostdata
->connected
, DID_RESET
);
2673 complete_cmd(instance
, hostdata
->sensing
);
2674 hostdata
->sensing
= NULL
;
2678 free_all_tags(hostdata
);
2680 for (i
= 0; i
< 8; ++i
)
2681 hostdata
->busy
[i
] = 0;
2683 hostdata
->dma_len
= 0;
2686 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
2687 maybe_release_dma_irq(instance
);
2688 spin_unlock_irqrestore(&hostdata
->lock
, flags
);