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 * ++roman: To port the 5380 driver to the Atari, I had to do some changes in
31 * - Some of the debug statements were incorrect (undefined variables and the
32 * like). I fixed that.
34 * - In information_transfer(), I think a #ifdef was wrong. Looking at the
35 * possible DMA transfer size should also happen for REAL_DMA. I added this
36 * in the #if statement.
38 * - When using real DMA, information_transfer() should return in a DATAOUT
39 * phase after starting the DMA. It has nothing more to do.
41 * - The interrupt service routine should run main after end of DMA, too (not
42 * only after RESELECTION interrupts). Additionally, it should _not_ test
43 * for more interrupts after running main, since a DMA process may have
44 * been started and interrupts are turned on now. The new int could happen
45 * inside the execution of NCR5380_intr(), leading to recursive
48 * - I've added a function merge_contiguous_buffers() that tries to
49 * merge scatter-gather buffers that are located at contiguous
50 * physical addresses and can be processed with the same DMA setup.
51 * Since most scatter-gather operations work on a page (4K) of
52 * 4 buffers (1K), in more than 90% of all cases three interrupts and
53 * DMA setup actions are saved.
55 * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA
56 * and USLEEP, because these were messing up readability and will never be
57 * needed for Atari SCSI.
59 * - I've revised the NCR5380_main() calling scheme (relax the 'main_running'
60 * stuff), and 'main' is executed in a bottom half if awoken by an
63 * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..."
64 * constructs. In my eyes, this made the source rather unreadable, so I
65 * finally replaced that by the *_PRINTK() macros.
69 /* Adapted for the sun3 by Sam Creasey. */
74 * This is a generic 5380 driver. To use it on a different platform,
75 * one simply writes appropriate system specific macros (ie, data
76 * transfer - some PC's will use the I/O bus, 68K's must use
77 * memory mapped) and drops this file in their 'C' wrapper.
79 * As far as command queueing, two queues are maintained for
80 * each 5380 in the system - commands that haven't been issued yet,
81 * and commands that are currently executing. This means that an
82 * unlimited number of commands may be queued, letting
83 * more commands propagate from the higher driver levels giving higher
84 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
85 * allowing multiple commands to propagate all the way to a SCSI-II device
86 * while a command is already executing.
89 * Issues specific to the NCR5380 :
91 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
92 * piece of hardware that requires you to sit in a loop polling for
93 * the REQ signal as long as you are connected. Some devices are
94 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
95 * while doing long seek operations. [...] These
96 * broken devices are the exception rather than the rule and I'd rather
97 * spend my time optimizing for the normal case.
101 * At the heart of the design is a coroutine, NCR5380_main,
102 * which is started from a workqueue for each NCR5380 host in the
103 * system. It attempts to establish I_T_L or I_T_L_Q nexuses by
104 * removing the commands from the issue queue and calling
105 * NCR5380_select() if a nexus is not established.
107 * Once a nexus is established, the NCR5380_information_transfer()
108 * phase goes through the various phases as instructed by the target.
109 * if the target goes into MSG IN and sends a DISCONNECT message,
110 * the command structure is placed into the per instance disconnected
111 * queue, and NCR5380_main tries to find more work. If the target is
112 * idle for too long, the system will try to sleep.
114 * If a command has disconnected, eventually an interrupt will trigger,
115 * calling NCR5380_intr() which will in turn call NCR5380_reselect
116 * to reestablish a nexus. This will run main if necessary.
118 * On command termination, the done function will be called as
121 * SCSI pointers are maintained in the SCp field of SCSI command
122 * structures, being initialized after the command is connected
123 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
124 * Note that in violation of the standard, an implicit SAVE POINTERS operation
125 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
130 * This file a skeleton Linux SCSI driver for the NCR 5380 series
131 * of chips. To use it, you write an architecture specific functions
132 * and macros and include this file in your driver.
134 * These macros control options :
135 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
136 * for commands that return with a CHECK CONDITION status.
138 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
141 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
143 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
145 * These macros MUST be defined :
147 * NCR5380_read(register) - read from the specified register
149 * NCR5380_write(register, value) - write to the specific register
151 * NCR5380_implementation_fields - additional fields needed for this
152 * specific implementation of the NCR5380
154 * Either real DMA *or* pseudo DMA may be implemented
156 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
157 * Note that the DMA setup functions should return the number of bytes
158 * that they were able to program the controller for.
160 * Also note that generic i386/PC versions of these macros are
161 * available as NCR5380_i386_dma_write_setup,
162 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
164 * NCR5380_dma_write_setup(instance, src, count) - initialize
165 * NCR5380_dma_read_setup(instance, dst, count) - initialize
166 * NCR5380_dma_residual(instance); - residual count
169 * NCR5380_pwrite(instance, src, count)
170 * NCR5380_pread(instance, dst, count);
172 * The generic driver is initialized by calling NCR5380_init(instance),
173 * after setting the appropriate host specific fields and ID. If the
174 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
175 * possible) function may be used.
178 #define HOSTNO instance->host_no
180 static int do_abort(struct Scsi_Host
*);
181 static void do_reset(struct Scsi_Host
*);
186 * Functions for handling tagged queuing
187 * =====================================
189 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
191 * Using consecutive numbers for the tags is no good idea in my eyes. There
192 * could be wrong re-usings if the counter (8 bit!) wraps and some early
193 * command has been preempted for a long time. My solution: a bitfield for
194 * remembering used tags.
196 * There's also the problem that each target has a certain queue size, but we
197 * cannot know it in advance :-( We just see a QUEUE_FULL status being
198 * returned. So, in this case, the driver internal queue size assumption is
199 * reduced to the number of active tags if QUEUE_FULL is returned by the
202 * We're also not allowed running tagged commands as long as an untagged
203 * command is active. And REQUEST SENSE commands after a contingent allegiance
204 * condition _must_ be untagged. To keep track whether an untagged command has
205 * been issued, the host->busy array is still employed, as it is without
206 * support for tagged queuing.
208 * One could suspect that there are possible race conditions between
209 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
210 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
211 * which already guaranteed to be running at most once. It is also the only
212 * place where tags/LUNs are allocated. So no other allocation can slip
213 * between that pair, there could only happen a reselection, which can free a
214 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
215 * important: the tag bit must be cleared before 'nr_allocated' is decreased.
218 static void __init
init_tags(struct NCR5380_hostdata
*hostdata
)
221 struct tag_alloc
*ta
;
223 if (!(hostdata
->flags
& FLAG_TAGGED_QUEUING
))
226 for (target
= 0; target
< 8; ++target
) {
227 for (lun
= 0; lun
< 8; ++lun
) {
228 ta
= &hostdata
->TagAlloc
[target
][lun
];
229 bitmap_zero(ta
->allocated
, MAX_TAGS
);
230 ta
->nr_allocated
= 0;
231 /* At the beginning, assume the maximum queue size we could
232 * support (MAX_TAGS). This value will be decreased if the target
233 * returns QUEUE_FULL status.
235 ta
->queue_size
= MAX_TAGS
;
241 /* Check if we can issue a command to this LUN: First see if the LUN is marked
242 * busy by an untagged command. If the command should use tagged queuing, also
243 * check that there is a free tag and the target's queue won't overflow. This
244 * function should be called with interrupts disabled to avoid race
248 static int is_lun_busy(struct scsi_cmnd
*cmd
, int should_be_tagged
)
250 u8 lun
= cmd
->device
->lun
;
251 struct Scsi_Host
*instance
= cmd
->device
->host
;
252 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
254 if (hostdata
->busy
[cmd
->device
->id
] & (1 << lun
))
256 if (!should_be_tagged
||
257 !(hostdata
->flags
& FLAG_TAGGED_QUEUING
) ||
258 !cmd
->device
->tagged_supported
)
260 if (hostdata
->TagAlloc
[scmd_id(cmd
)][lun
].nr_allocated
>=
261 hostdata
->TagAlloc
[scmd_id(cmd
)][lun
].queue_size
) {
262 dsprintk(NDEBUG_TAGS
, instance
, "target %d lun %d: no free tags\n",
270 /* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
271 * must be called before!), or reserve the LUN in 'busy' if the command is
275 static void cmd_get_tag(struct scsi_cmnd
*cmd
, int should_be_tagged
)
277 u8 lun
= cmd
->device
->lun
;
278 struct Scsi_Host
*instance
= cmd
->device
->host
;
279 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
281 /* If we or the target don't support tagged queuing, allocate the LUN for
282 * an untagged command.
284 if (!should_be_tagged
||
285 !(hostdata
->flags
& FLAG_TAGGED_QUEUING
) ||
286 !cmd
->device
->tagged_supported
) {
288 hostdata
->busy
[cmd
->device
->id
] |= (1 << lun
);
289 dsprintk(NDEBUG_TAGS
, instance
, "target %d lun %d now allocated by untagged command\n",
292 struct tag_alloc
*ta
= &hostdata
->TagAlloc
[scmd_id(cmd
)][lun
];
294 cmd
->tag
= find_first_zero_bit(ta
->allocated
, MAX_TAGS
);
295 set_bit(cmd
->tag
, ta
->allocated
);
297 dsprintk(NDEBUG_TAGS
, instance
, "using tag %d for target %d lun %d (%d tags allocated)\n",
298 cmd
->tag
, scmd_id(cmd
), lun
, ta
->nr_allocated
);
303 /* Mark the tag of command 'cmd' as free, or in case of an untagged command,
307 static void cmd_free_tag(struct scsi_cmnd
*cmd
)
309 u8 lun
= cmd
->device
->lun
;
310 struct Scsi_Host
*instance
= cmd
->device
->host
;
311 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
313 if (cmd
->tag
== TAG_NONE
) {
314 hostdata
->busy
[cmd
->device
->id
] &= ~(1 << lun
);
315 dsprintk(NDEBUG_TAGS
, instance
, "target %d lun %d untagged cmd freed\n",
317 } else if (cmd
->tag
>= MAX_TAGS
) {
318 shost_printk(KERN_NOTICE
, instance
,
319 "trying to free bad tag %d!\n", cmd
->tag
);
321 struct tag_alloc
*ta
= &hostdata
->TagAlloc
[scmd_id(cmd
)][lun
];
322 clear_bit(cmd
->tag
, ta
->allocated
);
324 dsprintk(NDEBUG_TAGS
, instance
, "freed tag %d for target %d lun %d\n",
325 cmd
->tag
, scmd_id(cmd
), lun
);
330 static void free_all_tags(struct NCR5380_hostdata
*hostdata
)
333 struct tag_alloc
*ta
;
335 if (!(hostdata
->flags
& FLAG_TAGGED_QUEUING
))
338 for (target
= 0; target
< 8; ++target
) {
339 for (lun
= 0; lun
< 8; ++lun
) {
340 ta
= &hostdata
->TagAlloc
[target
][lun
];
341 bitmap_zero(ta
->allocated
, MAX_TAGS
);
342 ta
->nr_allocated
= 0;
347 #endif /* SUPPORT_TAGS */
351 * Function: void merge_contiguous_buffers( struct scsi_cmnd *cmd )
353 * Purpose: Try to merge several scatter-gather requests into one DMA
354 * transfer. This is possible if the scatter buffers lie on
355 * physical contiguous addresses.
357 * Parameters: struct scsi_cmnd *cmd
358 * The command to work on. The first scatter buffer's data are
359 * assumed to be already transferred into ptr/this_residual.
362 static void merge_contiguous_buffers(struct scsi_cmnd
*cmd
)
364 #if !defined(CONFIG_SUN3)
365 unsigned long endaddr
;
366 #if (NDEBUG & NDEBUG_MERGING)
367 unsigned long oldlen
= cmd
->SCp
.this_residual
;
371 for (endaddr
= virt_to_phys(cmd
->SCp
.ptr
+ cmd
->SCp
.this_residual
- 1) + 1;
372 cmd
->SCp
.buffers_residual
&&
373 virt_to_phys(sg_virt(&cmd
->SCp
.buffer
[1])) == endaddr
;) {
374 dprintk(NDEBUG_MERGING
, "VTOP(%p) == %08lx -> merging\n",
375 page_address(sg_page(&cmd
->SCp
.buffer
[1])), endaddr
);
376 #if (NDEBUG & NDEBUG_MERGING)
380 --cmd
->SCp
.buffers_residual
;
381 cmd
->SCp
.this_residual
+= cmd
->SCp
.buffer
->length
;
382 endaddr
+= cmd
->SCp
.buffer
->length
;
384 #if (NDEBUG & NDEBUG_MERGING)
385 if (oldlen
!= cmd
->SCp
.this_residual
)
386 dprintk(NDEBUG_MERGING
, "merged %d buffers from %p, new length %08x\n",
387 cnt
, cmd
->SCp
.ptr
, cmd
->SCp
.this_residual
);
389 #endif /* !defined(CONFIG_SUN3) */
393 * initialize_SCp - init the scsi pointer field
394 * @cmd: command block to set up
396 * Set up the internal fields in the SCSI command.
399 static inline void initialize_SCp(struct scsi_cmnd
*cmd
)
402 * Initialize the Scsi Pointer field so that all of the commands in the
403 * various queues are valid.
406 if (scsi_bufflen(cmd
)) {
407 cmd
->SCp
.buffer
= scsi_sglist(cmd
);
408 cmd
->SCp
.buffers_residual
= scsi_sg_count(cmd
) - 1;
409 cmd
->SCp
.ptr
= sg_virt(cmd
->SCp
.buffer
);
410 cmd
->SCp
.this_residual
= cmd
->SCp
.buffer
->length
;
411 /* ++roman: Try to merge some scatter-buffers if they are at
412 * contiguous physical addresses.
414 merge_contiguous_buffers(cmd
);
416 cmd
->SCp
.buffer
= NULL
;
417 cmd
->SCp
.buffers_residual
= 0;
419 cmd
->SCp
.this_residual
= 0;
423 cmd
->SCp
.Message
= 0;
427 * NCR5380_poll_politely2 - wait for two chip register values
428 * @instance: controller to poll
429 * @reg1: 5380 register to poll
430 * @bit1: Bitmask to check
431 * @val1: Expected value
432 * @reg2: Second 5380 register to poll
433 * @bit2: Second bitmask to check
434 * @val2: Second expected value
435 * @wait: Time-out in jiffies
437 * Polls the chip in a reasonably efficient manner waiting for an
438 * event to occur. After a short quick poll we begin to yield the CPU
439 * (if possible). In irq contexts the time-out is arbitrarily limited.
440 * Callers may hold locks as long as they are held in irq mode.
442 * Returns 0 if either or both event(s) occurred otherwise -ETIMEDOUT.
445 static int NCR5380_poll_politely2(struct Scsi_Host
*instance
,
446 int reg1
, int bit1
, int val1
,
447 int reg2
, int bit2
, int val2
, int wait
)
449 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
450 unsigned long deadline
= jiffies
+ wait
;
453 /* Busy-wait for up to 10 ms */
454 n
= min(10000U, jiffies_to_usecs(wait
));
455 n
*= hostdata
->accesses_per_ms
;
458 if ((NCR5380_read(reg1
) & bit1
) == val1
)
460 if ((NCR5380_read(reg2
) & bit2
) == val2
)
465 if (irqs_disabled() || in_interrupt())
468 /* Repeatedly sleep for 1 ms until deadline */
469 while (time_is_after_jiffies(deadline
)) {
470 schedule_timeout_uninterruptible(1);
471 if ((NCR5380_read(reg1
) & bit1
) == val1
)
473 if ((NCR5380_read(reg2
) & bit2
) == val2
)
480 static inline int NCR5380_poll_politely(struct Scsi_Host
*instance
,
481 int reg
, int bit
, int val
, int wait
)
483 return NCR5380_poll_politely2(instance
, reg
, bit
, val
,
484 reg
, bit
, val
, wait
);
492 { SR_DBP
, "PARITY"}, { SR_RST
, "RST" }, { SR_BSY
, "BSY" },
493 { SR_REQ
, "REQ" }, { SR_MSG
, "MSG" }, { SR_CD
, "CD" }, { SR_IO
, "IO" },
494 { SR_SEL
, "SEL" }, {0, NULL
}
496 {BASR_ATN
, "ATN"}, {BASR_ACK
, "ACK"}, {0, NULL
}
498 {ICR_ASSERT_RST
, "ASSERT RST"},{ICR_ASSERT_ACK
, "ASSERT ACK"},
499 {ICR_ASSERT_BSY
, "ASSERT BSY"}, {ICR_ASSERT_SEL
, "ASSERT SEL"},
500 {ICR_ASSERT_ATN
, "ASSERT ATN"}, {ICR_ASSERT_DATA
, "ASSERT DATA"},
503 {MR_BLOCK_DMA_MODE
, "MODE BLOCK DMA"}, {MR_TARGET
, "MODE TARGET"},
504 {MR_ENABLE_PAR_CHECK
, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR
,
505 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR
,"MODE EOP INTR"},
506 {MR_MONITOR_BSY
, "MODE MONITOR BSY"},
507 {MR_DMA_MODE
, "MODE DMA"}, {MR_ARBITRATE
, "MODE ARBITRATION"},
512 * NCR5380_print - print scsi bus signals
513 * @instance: adapter state to dump
515 * Print the SCSI bus signals for debugging purposes
518 static void NCR5380_print(struct Scsi_Host
*instance
)
520 unsigned char status
, data
, basr
, mr
, icr
, i
;
522 data
= NCR5380_read(CURRENT_SCSI_DATA_REG
);
523 status
= NCR5380_read(STATUS_REG
);
524 mr
= NCR5380_read(MODE_REG
);
525 icr
= NCR5380_read(INITIATOR_COMMAND_REG
);
526 basr
= NCR5380_read(BUS_AND_STATUS_REG
);
528 printk("STATUS_REG: %02x ", status
);
529 for (i
= 0; signals
[i
].mask
; ++i
)
530 if (status
& signals
[i
].mask
)
531 printk(",%s", signals
[i
].name
);
532 printk("\nBASR: %02x ", basr
);
533 for (i
= 0; basrs
[i
].mask
; ++i
)
534 if (basr
& basrs
[i
].mask
)
535 printk(",%s", basrs
[i
].name
);
536 printk("\nICR: %02x ", icr
);
537 for (i
= 0; icrs
[i
].mask
; ++i
)
538 if (icr
& icrs
[i
].mask
)
539 printk(",%s", icrs
[i
].name
);
540 printk("\nMODE: %02x ", mr
);
541 for (i
= 0; mrs
[i
].mask
; ++i
)
542 if (mr
& mrs
[i
].mask
)
543 printk(",%s", mrs
[i
].name
);
551 {PHASE_DATAOUT
, "DATAOUT"}, {PHASE_DATAIN
, "DATAIN"}, {PHASE_CMDOUT
, "CMDOUT"},
552 {PHASE_STATIN
, "STATIN"}, {PHASE_MSGOUT
, "MSGOUT"}, {PHASE_MSGIN
, "MSGIN"},
553 {PHASE_UNKNOWN
, "UNKNOWN"}
557 * NCR5380_print_phase - show SCSI phase
558 * @instance: adapter to dump
560 * Print the current SCSI phase for debugging purposes
565 static void NCR5380_print_phase(struct Scsi_Host
*instance
)
567 unsigned char status
;
570 status
= NCR5380_read(STATUS_REG
);
571 if (!(status
& SR_REQ
))
572 printk(KERN_DEBUG
"scsi%d: REQ not asserted, phase unknown.\n", HOSTNO
);
574 for (i
= 0; (phases
[i
].value
!= PHASE_UNKNOWN
) &&
575 (phases
[i
].value
!= (status
& PHASE_MASK
)); ++i
)
577 printk(KERN_DEBUG
"scsi%d: phase %s\n", HOSTNO
, phases
[i
].name
);
584 * NCR58380_info - report driver and host information
585 * @instance: relevant scsi host instance
587 * For use as the host template info() handler.
592 static const char *NCR5380_info(struct Scsi_Host
*instance
)
594 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
596 return hostdata
->info
;
599 static void prepare_info(struct Scsi_Host
*instance
)
601 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
603 snprintf(hostdata
->info
, sizeof(hostdata
->info
),
604 "%s, io_port 0x%lx, n_io_port %d, "
605 "base 0x%lx, irq %d, "
606 "can_queue %d, cmd_per_lun %d, "
607 "sg_tablesize %d, this_id %d, "
610 instance
->hostt
->name
, instance
->io_port
, instance
->n_io_port
,
611 instance
->base
, instance
->irq
,
612 instance
->can_queue
, instance
->cmd_per_lun
,
613 instance
->sg_tablesize
, instance
->this_id
,
614 hostdata
->flags
& FLAG_TAGGED_QUEUING
? "TAGGED_QUEUING " : "",
615 hostdata
->flags
& FLAG_TOSHIBA_DELAY
? "TOSHIBA_DELAY " : "",
632 * NCR5380_init - initialise an NCR5380
633 * @instance: adapter to configure
634 * @flags: control flags
636 * Initializes *instance and corresponding 5380 chip,
637 * with flags OR'd into the initial flags value.
639 * Notes : I assume that the host, hostno, and id bits have been
640 * set correctly. I don't care about the irq and other fields.
642 * Returns 0 for success
645 static int __init
NCR5380_init(struct Scsi_Host
*instance
, int flags
)
647 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
649 unsigned long deadline
;
651 hostdata
->host
= instance
;
652 hostdata
->id_mask
= 1 << instance
->this_id
;
653 hostdata
->id_higher_mask
= 0;
654 for (i
= hostdata
->id_mask
; i
<= 0x80; i
<<= 1)
655 if (i
> hostdata
->id_mask
)
656 hostdata
->id_higher_mask
|= i
;
657 for (i
= 0; i
< 8; ++i
)
658 hostdata
->busy
[i
] = 0;
662 #if defined (REAL_DMA)
663 hostdata
->dma_len
= 0;
665 spin_lock_init(&hostdata
->lock
);
666 hostdata
->connected
= NULL
;
667 hostdata
->sensing
= NULL
;
668 INIT_LIST_HEAD(&hostdata
->autosense
);
669 INIT_LIST_HEAD(&hostdata
->unissued
);
670 INIT_LIST_HEAD(&hostdata
->disconnected
);
672 hostdata
->flags
= flags
;
674 INIT_WORK(&hostdata
->main_task
, NCR5380_main
);
675 hostdata
->work_q
= alloc_workqueue("ncr5380_%d",
676 WQ_UNBOUND
| WQ_MEM_RECLAIM
,
677 1, instance
->host_no
);
678 if (!hostdata
->work_q
)
681 prepare_info(instance
);
683 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
684 NCR5380_write(MODE_REG
, MR_BASE
);
685 NCR5380_write(TARGET_COMMAND_REG
, 0);
686 NCR5380_write(SELECT_ENABLE_REG
, 0);
688 /* Calibrate register polling loop */
690 deadline
= jiffies
+ 1;
693 } while (time_is_after_jiffies(deadline
));
694 deadline
+= msecs_to_jiffies(256);
696 NCR5380_read(STATUS_REG
);
699 } while (time_is_after_jiffies(deadline
));
700 hostdata
->accesses_per_ms
= i
/ 256;
706 * NCR5380_maybe_reset_bus - Detect and correct bus wedge problems.
707 * @instance: adapter to check
709 * If the system crashed, it may have crashed with a connected target and
710 * the SCSI bus busy. Check for BUS FREE phase. If not, try to abort the
711 * currently established nexus, which we know nothing about. Failing that
714 * Note that a bus reset will cause the chip to assert IRQ.
716 * Returns 0 if successful, otherwise -ENXIO.
719 static int NCR5380_maybe_reset_bus(struct Scsi_Host
*instance
)
721 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
724 for (pass
= 1; (NCR5380_read(STATUS_REG
) & SR_BSY
) && pass
<= 6; ++pass
) {
729 shost_printk(KERN_ERR
, instance
, "SCSI bus busy, waiting up to five seconds\n");
730 NCR5380_poll_politely(instance
,
731 STATUS_REG
, SR_BSY
, 0, 5 * HZ
);
734 shost_printk(KERN_ERR
, instance
, "bus busy, attempting abort\n");
738 shost_printk(KERN_ERR
, instance
, "bus busy, attempting reset\n");
740 /* Wait after a reset; the SCSI standard calls for
741 * 250ms, we wait 500ms to be on the safe side.
742 * But some Toshiba CD-ROMs need ten times that.
744 if (hostdata
->flags
& FLAG_TOSHIBA_DELAY
)
750 shost_printk(KERN_ERR
, instance
, "bus locked solid\n");
758 * NCR5380_exit - remove an NCR5380
759 * @instance: adapter to remove
761 * Assumes that no more work can be queued (e.g. by NCR5380_intr).
764 static void NCR5380_exit(struct Scsi_Host
*instance
)
766 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
768 cancel_work_sync(&hostdata
->main_task
);
769 destroy_workqueue(hostdata
->work_q
);
773 * complete_cmd - finish processing a command and return it to the SCSI ML
774 * @instance: the host instance
775 * @cmd: command to complete
778 static void complete_cmd(struct Scsi_Host
*instance
,
779 struct scsi_cmnd
*cmd
)
781 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
783 dsprintk(NDEBUG_QUEUES
, instance
, "complete_cmd: cmd %p\n", cmd
);
785 if (hostdata
->sensing
== cmd
) {
786 /* Autosense processing ends here */
787 if ((cmd
->result
& 0xff) != SAM_STAT_GOOD
) {
788 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
789 set_host_byte(cmd
, DID_ERROR
);
791 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
792 hostdata
->sensing
= NULL
;
798 hostdata
->busy
[scmd_id(cmd
)] &= ~(1 << cmd
->device
->lun
);
804 * NCR5380_queue_command - queue a command
805 * @instance: the relevant SCSI adapter
808 * cmd is added to the per-instance issue queue, with minor
809 * twiddling done to the host specific fields of cmd. If the
810 * main coroutine is not running, it is restarted.
813 static int NCR5380_queue_command(struct Scsi_Host
*instance
,
814 struct scsi_cmnd
*cmd
)
816 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
817 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
820 #if (NDEBUG & NDEBUG_NO_WRITE)
821 switch (cmd
->cmnd
[0]) {
824 shost_printk(KERN_DEBUG
, instance
, "WRITE attempted with NDEBUG_NO_WRITE set\n");
825 cmd
->result
= (DID_ERROR
<< 16);
829 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
834 * Insert the cmd into the issue queue. Note that REQUEST SENSE
835 * commands are added to the head of the queue since any command will
836 * clear the contingent allegiance condition that exists and the
837 * sense data is only guaranteed to be valid while the condition exists.
840 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
841 * Otherwise a running NCR5380_main may steal the lock.
842 * Lock before actually inserting due to fairness reasons explained in
843 * atari_scsi.c. If we insert first, then it's impossible for this driver
844 * to release the lock.
845 * Stop timer for this command while waiting for the lock, or timeouts
846 * may happen (and they really do), and it's no good if the command doesn't
847 * appear in any of the queues.
848 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
849 * because also a timer int can trigger an abort or reset, which would
850 * alter queues and touch the lock.
852 if (!NCR5380_acquire_dma_irq(instance
))
853 return SCSI_MLQUEUE_HOST_BUSY
;
855 spin_lock_irqsave(&hostdata
->lock
, flags
);
858 * Insert the cmd into the issue queue. Note that REQUEST SENSE
859 * commands are added to the head of the queue since any command will
860 * clear the contingent allegiance condition that exists and the
861 * sense data is only guaranteed to be valid while the condition exists.
864 if (cmd
->cmnd
[0] == REQUEST_SENSE
)
865 list_add(&ncmd
->list
, &hostdata
->unissued
);
867 list_add_tail(&ncmd
->list
, &hostdata
->unissued
);
869 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
871 dsprintk(NDEBUG_QUEUES
, instance
, "command %p added to %s of queue\n",
872 cmd
, (cmd
->cmnd
[0] == REQUEST_SENSE
) ? "head" : "tail");
874 /* Kick off command processing */
875 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
879 static inline void maybe_release_dma_irq(struct Scsi_Host
*instance
)
881 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
883 /* Caller does the locking needed to set & test these data atomically */
884 if (list_empty(&hostdata
->disconnected
) &&
885 list_empty(&hostdata
->unissued
) &&
886 list_empty(&hostdata
->autosense
) &&
887 !hostdata
->connected
&&
888 !hostdata
->retain_dma_intr
)
889 NCR5380_release_dma_irq(instance
);
893 * dequeue_next_cmd - dequeue a command for processing
894 * @instance: the scsi host instance
896 * Priority is given to commands on the autosense queue. These commands
897 * need autosense because of a CHECK CONDITION result.
899 * Returns a command pointer if a command is found for a target that is
900 * not already busy. Otherwise returns NULL.
903 static struct scsi_cmnd
*dequeue_next_cmd(struct Scsi_Host
*instance
)
905 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
906 struct NCR5380_cmd
*ncmd
;
907 struct scsi_cmnd
*cmd
;
909 if (list_empty(&hostdata
->autosense
)) {
910 list_for_each_entry(ncmd
, &hostdata
->unissued
, list
) {
911 cmd
= NCR5380_to_scmd(ncmd
);
912 dsprintk(NDEBUG_QUEUES
, instance
, "dequeue: cmd=%p target=%d busy=0x%02x lun=%llu\n",
913 cmd
, scmd_id(cmd
), hostdata
->busy
[scmd_id(cmd
)], cmd
->device
->lun
);
919 !(hostdata
->busy
[scmd_id(cmd
)] & (1 << cmd
->device
->lun
))
922 list_del(&ncmd
->list
);
923 dsprintk(NDEBUG_QUEUES
, instance
,
924 "dequeue: removed %p from issue queue\n", cmd
);
929 /* Autosense processing begins here */
930 ncmd
= list_first_entry(&hostdata
->autosense
,
931 struct NCR5380_cmd
, list
);
932 list_del(&ncmd
->list
);
933 cmd
= NCR5380_to_scmd(ncmd
);
934 dsprintk(NDEBUG_QUEUES
, instance
,
935 "dequeue: removed %p from autosense queue\n", cmd
);
936 scsi_eh_prep_cmnd(cmd
, &hostdata
->ses
, NULL
, 0, ~0);
937 hostdata
->sensing
= cmd
;
943 static void requeue_cmd(struct Scsi_Host
*instance
, struct scsi_cmnd
*cmd
)
945 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
946 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
948 if (hostdata
->sensing
) {
949 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
950 list_add(&ncmd
->list
, &hostdata
->autosense
);
951 hostdata
->sensing
= NULL
;
953 list_add(&ncmd
->list
, &hostdata
->unissued
);
957 * NCR5380_main - NCR state machines
959 * NCR5380_main is a coroutine that runs as long as more work can
960 * be done on the NCR5380 host adapters in a system. Both
961 * NCR5380_queue_command() and NCR5380_intr() will try to start it
962 * in case it is not running.
964 * Locks: called as its own thread with no locks held.
967 static void NCR5380_main(struct work_struct
*work
)
969 struct NCR5380_hostdata
*hostdata
=
970 container_of(work
, struct NCR5380_hostdata
, main_task
);
971 struct Scsi_Host
*instance
= hostdata
->host
;
972 struct scsi_cmnd
*cmd
;
976 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
977 * because also a timer int can trigger an abort or reset, which can
978 * alter queues and touch the Falcon lock.
981 spin_lock_irq(&hostdata
->lock
);
985 while (!hostdata
->connected
&&
986 (cmd
= dequeue_next_cmd(instance
))) {
988 dsprintk(NDEBUG_MAIN
, instance
, "main: dequeued %p\n", cmd
);
991 * Attempt to establish an I_T_L nexus here.
992 * On success, instance->hostdata->connected is set.
993 * On failure, we must add the command back to the
994 * issue queue so we can keep trying.
997 * REQUEST SENSE commands are issued without tagged
998 * queueing, even on SCSI-II devices because the
999 * contingent allegiance condition exists for the
1002 /* ++roman: ...and the standard also requires that
1003 * REQUEST SENSE command are untagged.
1007 cmd_get_tag(cmd
, cmd
->cmnd
[0] != REQUEST_SENSE
);
1009 hostdata
->retain_dma_intr
++;
1010 if (!NCR5380_select(instance
, cmd
)) {
1011 dsprintk(NDEBUG_MAIN
, instance
, "main: selected target %d for command %p\n",
1013 hostdata
->retain_dma_intr
--;
1014 maybe_release_dma_irq(instance
);
1016 hostdata
->retain_dma_intr
--;
1017 dsprintk(NDEBUG_MAIN
| NDEBUG_QUEUES
, instance
,
1018 "main: select failed, returning %p to queue\n", cmd
);
1019 requeue_cmd(instance
, cmd
);
1025 if (hostdata
->connected
1027 && !hostdata
->dma_len
1030 dprintk(NDEBUG_MAIN
, "scsi%d: main: performing information transfer\n",
1032 NCR5380_information_transfer(instance
);
1033 dprintk(NDEBUG_MAIN
, "scsi%d: main: done set false\n", HOSTNO
);
1037 spin_unlock_irq(&hostdata
->lock
);
1043 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1045 * Purpose : Called by interrupt handler when DMA finishes or a phase
1046 * mismatch occurs (which would finish the DMA transfer).
1048 * Inputs : instance - this instance of the NCR5380.
1052 static void NCR5380_dma_complete(struct Scsi_Host
*instance
)
1054 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1056 unsigned char **data
;
1058 int saved_data
= 0, overrun
= 0;
1061 if (hostdata
->read_overruns
) {
1062 p
= hostdata
->connected
->SCp
.phase
;
1065 if ((NCR5380_read(BUS_AND_STATUS_REG
) &
1066 (BASR_PHASE_MATCH
|BASR_ACK
)) ==
1067 (BASR_PHASE_MATCH
|BASR_ACK
)) {
1068 saved_data
= NCR5380_read(INPUT_DATA_REG
);
1070 dprintk(NDEBUG_DMA
, "scsi%d: read overrun handled\n", HOSTNO
);
1075 #if defined(CONFIG_SUN3)
1076 if ((sun3scsi_dma_finish(rq_data_dir(hostdata
->connected
->request
)))) {
1077 pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n",
1082 /* make sure we're not stuck in a data phase */
1083 if ((NCR5380_read(BUS_AND_STATUS_REG
) & (BASR_PHASE_MATCH
| BASR_ACK
)) ==
1084 (BASR_PHASE_MATCH
| BASR_ACK
)) {
1085 pr_err("scsi%d: BASR %02x\n", instance
->host_no
,
1086 NCR5380_read(BUS_AND_STATUS_REG
));
1087 pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n",
1093 NCR5380_write(MODE_REG
, MR_BASE
);
1094 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1095 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1097 transferred
= hostdata
->dma_len
- NCR5380_dma_residual(instance
);
1098 hostdata
->dma_len
= 0;
1100 data
= (unsigned char **)&hostdata
->connected
->SCp
.ptr
;
1101 count
= &hostdata
->connected
->SCp
.this_residual
;
1102 *data
+= transferred
;
1103 *count
-= transferred
;
1105 if (hostdata
->read_overruns
) {
1108 if ((NCR5380_read(STATUS_REG
) & PHASE_MASK
) == p
&& (p
& SR_IO
)) {
1109 cnt
= toPIO
= hostdata
->read_overruns
;
1111 dprintk(NDEBUG_DMA
, "Got an input overrun, using saved byte\n");
1112 *(*data
)++ = saved_data
;
1117 dprintk(NDEBUG_DMA
, "Doing %d-byte PIO to 0x%08lx\n", cnt
, (long)*data
);
1118 NCR5380_transfer_pio(instance
, &p
, &cnt
, data
);
1119 *count
-= toPIO
- cnt
;
1123 #endif /* REAL_DMA */
1127 * NCR5380_intr - generic NCR5380 irq handler
1128 * @irq: interrupt number
1129 * @dev_id: device info
1131 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1132 * from the disconnected queue, and restarting NCR5380_main()
1135 * The chip can assert IRQ in any of six different conditions. The IRQ flag
1136 * is then cleared by reading the Reset Parity/Interrupt Register (RPIR).
1137 * Three of these six conditions are latched in the Bus and Status Register:
1138 * - End of DMA (cleared by ending DMA Mode)
1139 * - Parity error (cleared by reading RPIR)
1140 * - Loss of BSY (cleared by reading RPIR)
1141 * Two conditions have flag bits that are not latched:
1142 * - Bus phase mismatch (non-maskable in DMA Mode, cleared by ending DMA Mode)
1143 * - Bus reset (non-maskable)
1144 * The remaining condition has no flag bit at all:
1145 * - Selection/reselection
1147 * Hence, establishing the cause(s) of any interrupt is partly guesswork.
1148 * In "The DP8490 and DP5380 Comparison Guide", National Semiconductor
1149 * claimed that "the design of the [DP8490] interrupt logic ensures
1150 * interrupts will not be lost (they can be on the DP5380)."
1151 * The L5380/53C80 datasheet from LOGIC Devices has more details.
1153 * Checking for bus reset by reading RST is futile because of interrupt
1154 * latency, but a bus reset will reset chip logic. Checking for parity error
1155 * is unnecessary because that interrupt is never enabled. A Loss of BSY
1156 * condition will clear DMA Mode. We can tell when this occurs because the
1157 * the Busy Monitor interrupt is enabled together with DMA Mode.
1160 static irqreturn_t
NCR5380_intr(int irq
, void *dev_id
)
1162 struct Scsi_Host
*instance
= dev_id
;
1163 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1166 unsigned long flags
;
1168 spin_lock_irqsave(&hostdata
->lock
, flags
);
1170 basr
= NCR5380_read(BUS_AND_STATUS_REG
);
1171 if (basr
& BASR_IRQ
) {
1172 unsigned char mr
= NCR5380_read(MODE_REG
);
1173 unsigned char sr
= NCR5380_read(STATUS_REG
);
1175 dprintk(NDEBUG_INTR
, "scsi%d: IRQ %d, BASR 0x%02x, SR 0x%02x, MR 0x%02x\n",
1176 HOSTNO
, irq
, basr
, sr
, mr
);
1178 #if defined(REAL_DMA)
1179 if ((mr
& MR_DMA_MODE
) || (mr
& MR_MONITOR_BSY
)) {
1180 /* Probably End of DMA, Phase Mismatch or Loss of BSY.
1181 * We ack IRQ after clearing Mode Register. Workarounds
1182 * for End of DMA errata need to happen in DMA Mode.
1185 dprintk(NDEBUG_INTR
, "scsi%d: interrupt in DMA mode\n", HOSTNO
);
1187 if (hostdata
->connected
) {
1188 NCR5380_dma_complete(instance
);
1189 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
1191 NCR5380_write(MODE_REG
, MR_BASE
);
1192 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1195 #endif /* REAL_DMA */
1196 if ((NCR5380_read(CURRENT_SCSI_DATA_REG
) & hostdata
->id_mask
) &&
1197 (sr
& (SR_SEL
| SR_IO
| SR_BSY
| SR_RST
)) == (SR_SEL
| SR_IO
)) {
1198 /* Probably reselected */
1199 NCR5380_write(SELECT_ENABLE_REG
, 0);
1200 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1202 dprintk(NDEBUG_INTR
, "scsi%d: interrupt with SEL and IO\n",
1205 if (!hostdata
->connected
) {
1206 NCR5380_reselect(instance
);
1207 queue_work(hostdata
->work_q
, &hostdata
->main_task
);
1209 if (!hostdata
->connected
)
1210 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1212 /* Probably Bus Reset */
1213 NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1215 dprintk(NDEBUG_INTR
, "scsi%d: unknown interrupt\n", HOSTNO
);
1216 #ifdef SUN3_SCSI_VME
1217 dregs
->csr
|= CSR_DMA_ENABLE
;
1222 shost_printk(KERN_NOTICE
, instance
, "interrupt without IRQ bit\n");
1223 #ifdef SUN3_SCSI_VME
1224 dregs
->csr
|= CSR_DMA_ENABLE
;
1228 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
1230 return IRQ_RETVAL(handled
);
1234 * Function : int NCR5380_select(struct Scsi_Host *instance,
1235 * struct scsi_cmnd *cmd)
1237 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1238 * including ARBITRATION, SELECTION, and initial message out for
1239 * IDENTIFY and queue messages.
1241 * Inputs : instance - instantiation of the 5380 driver on which this
1242 * target lives, cmd - SCSI command to execute.
1244 * Returns : -1 if selection failed but should be retried.
1245 * 0 if selection failed and should not be retried.
1246 * 0 if selection succeeded completely (hostdata->connected == cmd).
1249 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1250 * with registers as they should have been on entry - ie
1251 * SELECT_ENABLE will be set appropriately, the NCR5380
1252 * will cease to drive any SCSI bus signals.
1254 * If successful : I_T_L or I_T_L_Q nexus will be established,
1255 * instance->connected will be set to cmd.
1256 * SELECT interrupt will be disabled.
1258 * If failed (no target) : cmd->scsi_done() will be called, and the
1259 * cmd->result host byte set to DID_BAD_TARGET.
1262 static int NCR5380_select(struct Scsi_Host
*instance
, struct scsi_cmnd
*cmd
)
1264 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1265 unsigned char tmp
[3], phase
;
1266 unsigned char *data
;
1270 NCR5380_dprint(NDEBUG_ARBITRATION
, instance
);
1271 dprintk(NDEBUG_ARBITRATION
, "scsi%d: starting arbitration, id = %d\n", HOSTNO
,
1275 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1276 * data bus during SELECTION.
1279 NCR5380_write(TARGET_COMMAND_REG
, 0);
1282 * Start arbitration.
1285 NCR5380_write(OUTPUT_DATA_REG
, hostdata
->id_mask
);
1286 NCR5380_write(MODE_REG
, MR_ARBITRATE
);
1288 /* The chip now waits for BUS FREE phase. Then after the 800 ns
1289 * Bus Free Delay, arbitration will begin.
1292 spin_unlock_irq(&hostdata
->lock
);
1293 err
= NCR5380_poll_politely2(instance
, MODE_REG
, MR_ARBITRATE
, 0,
1294 INITIATOR_COMMAND_REG
, ICR_ARBITRATION_PROGRESS
,
1295 ICR_ARBITRATION_PROGRESS
, HZ
);
1296 spin_lock_irq(&hostdata
->lock
);
1297 if (!(NCR5380_read(MODE_REG
) & MR_ARBITRATE
)) {
1298 /* Reselection interrupt */
1302 NCR5380_write(MODE_REG
, MR_BASE
);
1303 shost_printk(KERN_ERR
, instance
,
1304 "select: arbitration timeout\n");
1307 spin_unlock_irq(&hostdata
->lock
);
1309 /* The SCSI-2 arbitration delay is 2.4 us */
1312 /* Check for lost arbitration */
1313 if ((NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_LOST
) ||
1314 (NCR5380_read(CURRENT_SCSI_DATA_REG
) & hostdata
->id_higher_mask
) ||
1315 (NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_LOST
)) {
1316 NCR5380_write(MODE_REG
, MR_BASE
);
1317 dprintk(NDEBUG_ARBITRATION
, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1319 spin_lock_irq(&hostdata
->lock
);
1323 /* After/during arbitration, BSY should be asserted.
1324 * IBM DPES-31080 Version S31Q works now
1325 * Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman)
1327 NCR5380_write(INITIATOR_COMMAND_REG
,
1328 ICR_BASE
| ICR_ASSERT_SEL
| ICR_ASSERT_BSY
);
1331 * Again, bus clear + bus settle time is 1.2us, however, this is
1332 * a minimum so we'll udelay ceil(1.2)
1335 if (hostdata
->flags
& FLAG_TOSHIBA_DELAY
)
1340 spin_lock_irq(&hostdata
->lock
);
1342 /* NCR5380_reselect() clears MODE_REG after a reselection interrupt */
1343 if (!(NCR5380_read(MODE_REG
) & MR_ARBITRATE
))
1346 dprintk(NDEBUG_ARBITRATION
, "scsi%d: won arbitration\n", HOSTNO
);
1349 * Now that we have won arbitration, start Selection process, asserting
1350 * the host and target ID's on the SCSI bus.
1353 NCR5380_write(OUTPUT_DATA_REG
, (hostdata
->id_mask
| (1 << cmd
->device
->id
)));
1356 * Raise ATN while SEL is true before BSY goes false from arbitration,
1357 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1358 * phase immediately after selection.
1361 NCR5380_write(INITIATOR_COMMAND_REG
, (ICR_BASE
| ICR_ASSERT_BSY
|
1362 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
| ICR_ASSERT_SEL
));
1363 NCR5380_write(MODE_REG
, MR_BASE
);
1366 * Reselect interrupts must be turned off prior to the dropping of BSY,
1367 * otherwise we will trigger an interrupt.
1369 NCR5380_write(SELECT_ENABLE_REG
, 0);
1371 spin_unlock_irq(&hostdata
->lock
);
1374 * The initiator shall then wait at least two deskew delays and release
1377 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1380 NCR5380_write(INITIATOR_COMMAND_REG
, (ICR_BASE
| ICR_ASSERT_DATA
|
1381 ICR_ASSERT_ATN
| ICR_ASSERT_SEL
));
1384 * Something weird happens when we cease to drive BSY - looks
1385 * like the board/chip is letting us do another read before the
1386 * appropriate propagation delay has expired, and we're confusing
1387 * a BSY signal from ourselves as the target's response to SELECTION.
1389 * A small delay (the 'C++' frontend breaks the pipeline with an
1390 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1391 * tighter 'C' code breaks and requires this) solves the problem -
1392 * the 1 us delay is arbitrary, and only used because this delay will
1393 * be the same on other platforms and since it works here, it should
1396 * wingel suggests that this could be due to failing to wait
1402 dprintk(NDEBUG_SELECTION
, "scsi%d: selecting target %d\n", HOSTNO
, cmd
->device
->id
);
1405 * The SCSI specification calls for a 250 ms timeout for the actual
1409 err
= NCR5380_poll_politely(instance
, STATUS_REG
, SR_BSY
, SR_BSY
,
1410 msecs_to_jiffies(250));
1412 if ((NCR5380_read(STATUS_REG
) & (SR_SEL
| SR_IO
)) == (SR_SEL
| SR_IO
)) {
1413 spin_lock_irq(&hostdata
->lock
);
1414 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1415 NCR5380_reselect(instance
);
1416 if (!hostdata
->connected
)
1417 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1418 printk(KERN_ERR
"scsi%d: reselection after won arbitration?\n",
1424 spin_lock_irq(&hostdata
->lock
);
1425 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1426 cmd
->result
= DID_BAD_TARGET
<< 16;
1427 complete_cmd(instance
, cmd
);
1428 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1429 dprintk(NDEBUG_SELECTION
, "scsi%d: target did not respond within 250ms\n", HOSTNO
);
1434 * No less than two deskew delays after the initiator detects the
1435 * BSY signal is true, it shall release the SEL signal and may
1436 * change the DATA BUS. -wingel
1441 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1444 * Since we followed the SCSI spec, and raised ATN while SEL
1445 * was true but before BSY was false during selection, the information
1446 * transfer phase should be a MESSAGE OUT phase so that we can send the
1449 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1450 * message (2 bytes) with a tag ID that we increment with every command
1451 * until it wraps back to 0.
1453 * XXX - it turns out that there are some broken SCSI-II devices,
1454 * which claim to support tagged queuing but fail when more than
1455 * some number of commands are issued at once.
1458 /* Wait for start of REQ/ACK handshake */
1460 err
= NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, SR_REQ
, HZ
);
1461 spin_lock_irq(&hostdata
->lock
);
1463 shost_printk(KERN_ERR
, instance
, "select: REQ timeout\n");
1464 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1465 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1469 dprintk(NDEBUG_SELECTION
, "scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1470 HOSTNO
, cmd
->device
->id
);
1471 tmp
[0] = IDENTIFY(1, cmd
->device
->lun
);
1474 if (cmd
->tag
!= TAG_NONE
) {
1475 tmp
[1] = hostdata
->last_message
= SIMPLE_QUEUE_TAG
;
1483 #endif /* SUPPORT_TAGS */
1485 /* Send message(s) */
1487 phase
= PHASE_MSGOUT
;
1488 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
1489 dprintk(NDEBUG_SELECTION
, "scsi%d: nexus established.\n", HOSTNO
);
1490 /* XXX need to handle errors here */
1492 hostdata
->connected
= cmd
;
1493 #ifndef SUPPORT_TAGS
1494 hostdata
->busy
[cmd
->device
->id
] |= (1 << cmd
->device
->lun
);
1496 #ifdef SUN3_SCSI_VME
1497 dregs
->csr
|= CSR_INTR
;
1500 initialize_SCp(cmd
);
1506 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1507 * unsigned char *phase, int *count, unsigned char **data)
1509 * Purpose : transfers data in given phase using polled I/O
1511 * Inputs : instance - instance of driver, *phase - pointer to
1512 * what phase is expected, *count - pointer to number of
1513 * bytes to transfer, **data - pointer to data pointer.
1515 * Returns : -1 when different phase is entered without transferring
1516 * maximum number of bytes, 0 if all bytes are transferred or exit
1519 * Also, *phase, *count, *data are modified in place.
1521 * XXX Note : handling for bus free may be useful.
1525 * Note : this code is not as quick as it could be, however it
1526 * IS 100% reliable, and for the actual data transfer where speed
1527 * counts, we will always do a pseudo DMA or DMA transfer.
1530 static int NCR5380_transfer_pio(struct Scsi_Host
*instance
,
1531 unsigned char *phase
, int *count
,
1532 unsigned char **data
)
1534 register unsigned char p
= *phase
, tmp
;
1535 register int c
= *count
;
1536 register unsigned char *d
= *data
;
1539 * The NCR5380 chip will only drive the SCSI bus when the
1540 * phase specified in the appropriate bits of the TARGET COMMAND
1541 * REGISTER match the STATUS REGISTER
1544 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1548 * Wait for assertion of REQ, after which the phase bits will be
1552 if (NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, SR_REQ
, HZ
) < 0)
1555 dprintk(NDEBUG_HANDSHAKE
, "scsi%d: REQ detected\n", HOSTNO
);
1557 /* Check for phase mismatch */
1558 if ((NCR5380_read(STATUS_REG
) & PHASE_MASK
) != p
) {
1559 dprintk(NDEBUG_PIO
, "scsi%d: phase mismatch\n", HOSTNO
);
1560 NCR5380_dprint_phase(NDEBUG_PIO
, instance
);
1564 /* Do actual transfer from SCSI bus to / from memory */
1566 NCR5380_write(OUTPUT_DATA_REG
, *d
);
1568 *d
= NCR5380_read(CURRENT_SCSI_DATA_REG
);
1573 * The SCSI standard suggests that in MSGOUT phase, the initiator
1574 * should drop ATN on the last byte of the message phase
1575 * after REQ has been asserted for the handshake but before
1576 * the initiator raises ACK.
1580 if (!((p
& SR_MSG
) && c
> 1)) {
1581 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
);
1582 NCR5380_dprint(NDEBUG_PIO
, instance
);
1583 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1584 ICR_ASSERT_DATA
| ICR_ASSERT_ACK
);
1586 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1587 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
);
1588 NCR5380_dprint(NDEBUG_PIO
, instance
);
1589 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1590 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
| ICR_ASSERT_ACK
);
1593 NCR5380_dprint(NDEBUG_PIO
, instance
);
1594 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ACK
);
1597 if (NCR5380_poll_politely(instance
,
1598 STATUS_REG
, SR_REQ
, 0, 5 * HZ
) < 0)
1601 dprintk(NDEBUG_HANDSHAKE
, "scsi%d: req false, handshake complete\n", HOSTNO
);
1604 * We have several special cases to consider during REQ/ACK handshaking :
1605 * 1. We were in MSGOUT phase, and we are on the last byte of the
1606 * message. ATN must be dropped as ACK is dropped.
1608 * 2. We are in a MSGIN phase, and we are on the last byte of the
1609 * message. We must exit with ACK asserted, so that the calling
1610 * code may raise ATN before dropping ACK to reject the message.
1612 * 3. ACK and ATN are clear and the target may proceed as normal.
1614 if (!(p
== PHASE_MSGIN
&& c
== 1)) {
1615 if (p
== PHASE_MSGOUT
&& c
> 1)
1616 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1618 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1622 dprintk(NDEBUG_PIO
, "scsi%d: residual %d\n", HOSTNO
, c
);
1626 tmp
= NCR5380_read(STATUS_REG
);
1627 /* The phase read from the bus is valid if either REQ is (already)
1628 * asserted or if ACK hasn't been released yet. The latter applies if
1629 * we're in MSG IN, DATA IN or STATUS and all bytes have been received.
1631 if ((tmp
& SR_REQ
) || ((tmp
& SR_IO
) && c
== 0))
1632 *phase
= tmp
& PHASE_MASK
;
1634 *phase
= PHASE_UNKNOWN
;
1636 if (!c
|| (*phase
== p
))
1643 * do_reset - issue a reset command
1644 * @instance: adapter to reset
1646 * Issue a reset sequence to the NCR5380 and try and get the bus
1647 * back into sane shape.
1649 * This clears the reset interrupt flag because there may be no handler for
1650 * it. When the driver is initialized, the NCR5380_intr() handler has not yet
1651 * been installed. And when in EH we may have released the ST DMA interrupt.
1654 static void do_reset(struct Scsi_Host
*instance
)
1656 unsigned long flags
;
1658 local_irq_save(flags
);
1659 NCR5380_write(TARGET_COMMAND_REG
,
1660 PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG
) & PHASE_MASK
));
1661 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_RST
);
1663 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1664 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1665 local_irq_restore(flags
);
1669 * do_abort - abort the currently established nexus by going to
1670 * MESSAGE OUT phase and sending an ABORT message.
1671 * @instance: relevant scsi host instance
1673 * Returns 0 on success, -1 on failure.
1676 static int do_abort(struct Scsi_Host
*instance
)
1678 unsigned char tmp
, *msgptr
, phase
;
1682 /* Request message out phase */
1683 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1686 * Wait for the target to indicate a valid phase by asserting
1687 * REQ. Once this happens, we'll have either a MSGOUT phase
1688 * and can immediately send the ABORT message, or we'll have some
1689 * other phase and will have to source/sink data.
1691 * We really don't care what value was on the bus or what value
1692 * the target sees, so we just handshake.
1695 rc
= NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, SR_REQ
, 10 * HZ
);
1699 tmp
= NCR5380_read(STATUS_REG
) & PHASE_MASK
;
1701 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(tmp
));
1703 if (tmp
!= PHASE_MSGOUT
) {
1704 NCR5380_write(INITIATOR_COMMAND_REG
,
1705 ICR_BASE
| ICR_ASSERT_ATN
| ICR_ASSERT_ACK
);
1706 rc
= NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, 0, 3 * HZ
);
1709 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1715 phase
= PHASE_MSGOUT
;
1716 NCR5380_transfer_pio(instance
, &phase
, &len
, &msgptr
);
1719 * If we got here, and the command completed successfully,
1720 * we're about to go into bus free state.
1723 return len
? -1 : 0;
1726 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1730 #if defined(REAL_DMA)
1732 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1733 * unsigned char *phase, int *count, unsigned char **data)
1735 * Purpose : transfers data in given phase using either real
1738 * Inputs : instance - instance of driver, *phase - pointer to
1739 * what phase is expected, *count - pointer to number of
1740 * bytes to transfer, **data - pointer to data pointer.
1742 * Returns : -1 when different phase is entered without transferring
1743 * maximum number of bytes, 0 if all bytes or transferred or exit
1746 * Also, *phase, *count, *data are modified in place.
1751 static int NCR5380_transfer_dma(struct Scsi_Host
*instance
,
1752 unsigned char *phase
, int *count
,
1753 unsigned char **data
)
1755 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1756 register int c
= *count
;
1757 register unsigned char p
= *phase
;
1759 #if defined(CONFIG_SUN3)
1761 if (!sun3_dma_setup_done
) {
1762 pr_err("scsi%d: transfer_dma without setup!\n",
1766 hostdata
->dma_len
= c
;
1768 dprintk(NDEBUG_DMA
, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1769 instance
->host_no
, (p
& SR_IO
) ? "reading" : "writing",
1770 c
, (p
& SR_IO
) ? "to" : "from", *data
);
1772 /* netbsd turns off ints here, why not be safe and do it too */
1774 /* send start chain */
1775 sun3scsi_dma_start(c
, *data
);
1777 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1778 NCR5380_write(MODE_REG
, MR_BASE
| MR_DMA_MODE
| MR_MONITOR_BSY
|
1779 MR_ENABLE_EOP_INTR
);
1781 NCR5380_write(INITIATOR_COMMAND_REG
, 0);
1782 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG
, 0);
1784 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_ASSERT_DATA
);
1785 NCR5380_write(START_DMA_SEND_REG
, 0);
1788 #ifdef SUN3_SCSI_VME
1789 dregs
->csr
|= CSR_DMA_ENABLE
;
1792 sun3_dma_active
= 1;
1794 #else /* !defined(CONFIG_SUN3) */
1795 register unsigned char *d
= *data
;
1798 if ((tmp
= (NCR5380_read(STATUS_REG
) & PHASE_MASK
)) != p
) {
1803 if (hostdata
->read_overruns
&& (p
& SR_IO
))
1804 c
-= hostdata
->read_overruns
;
1806 dprintk(NDEBUG_DMA
, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1807 HOSTNO
, (p
& SR_IO
) ? "reading" : "writing",
1808 c
, (p
& SR_IO
) ? "to" : "from", d
);
1810 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1811 NCR5380_write(MODE_REG
, MR_BASE
| MR_DMA_MODE
| MR_MONITOR_BSY
|
1812 MR_ENABLE_EOP_INTR
);
1814 if (!(hostdata
->flags
& FLAG_LATE_DMA_SETUP
)) {
1815 /* On the Medusa, it is a must to initialize the DMA before
1816 * starting the NCR. This is also the cleaner way for the TT.
1818 hostdata
->dma_len
= (p
& SR_IO
) ?
1819 NCR5380_dma_read_setup(instance
, d
, c
) :
1820 NCR5380_dma_write_setup(instance
, d
, c
);
1824 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG
, 0);
1826 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
);
1827 NCR5380_write(START_DMA_SEND_REG
, 0);
1830 if (hostdata
->flags
& FLAG_LATE_DMA_SETUP
) {
1831 /* On the Falcon, the DMA setup must be done after the last */
1832 /* NCR access, else the DMA setup gets trashed!
1834 hostdata
->dma_len
= (p
& SR_IO
) ?
1835 NCR5380_dma_read_setup(instance
, d
, c
) :
1836 NCR5380_dma_write_setup(instance
, d
, c
);
1838 #endif /* !defined(CONFIG_SUN3) */
1842 #endif /* defined(REAL_DMA) */
1845 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1847 * Purpose : run through the various SCSI phases and do as the target
1848 * directs us to. Operates on the currently connected command,
1849 * instance->connected.
1851 * Inputs : instance, instance for which we are doing commands
1853 * Side effects : SCSI things happen, the disconnected queue will be
1854 * modified if a command disconnects, *instance->connected will
1857 * XXX Note : we need to watch for bus free or a reset condition here
1858 * to recover from an unexpected bus free condition.
1861 static void NCR5380_information_transfer(struct Scsi_Host
*instance
)
1863 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
1864 unsigned char msgout
= NOP
;
1867 #if defined(REAL_DMA)
1870 unsigned char *data
;
1871 unsigned char phase
, tmp
, extended_msg
[10], old_phase
= 0xff;
1872 struct scsi_cmnd
*cmd
;
1874 #ifdef SUN3_SCSI_VME
1875 dregs
->csr
|= CSR_INTR
;
1878 while ((cmd
= hostdata
->connected
)) {
1879 struct NCR5380_cmd
*ncmd
= scsi_cmd_priv(cmd
);
1881 tmp
= NCR5380_read(STATUS_REG
);
1882 /* We only have a valid SCSI phase when REQ is asserted */
1884 phase
= (tmp
& PHASE_MASK
);
1885 if (phase
!= old_phase
) {
1887 NCR5380_dprint_phase(NDEBUG_INFORMATION
, instance
);
1889 #if defined(CONFIG_SUN3)
1890 if (phase
== PHASE_CMDOUT
) {
1891 #if defined(REAL_DMA)
1893 unsigned long count
;
1895 if (!cmd
->SCp
.this_residual
&& cmd
->SCp
.buffers_residual
) {
1896 count
= cmd
->SCp
.buffer
->length
;
1897 d
= sg_virt(cmd
->SCp
.buffer
);
1899 count
= cmd
->SCp
.this_residual
;
1902 /* this command setup for dma yet? */
1903 if ((count
>= DMA_MIN_SIZE
) && (sun3_dma_setup_done
!= cmd
)) {
1904 if (cmd
->request
->cmd_type
== REQ_TYPE_FS
) {
1905 sun3scsi_dma_setup(d
, count
,
1906 rq_data_dir(cmd
->request
));
1907 sun3_dma_setup_done
= cmd
;
1911 #ifdef SUN3_SCSI_VME
1912 dregs
->csr
|= CSR_INTR
;
1915 #endif /* CONFIG_SUN3 */
1917 if (sink
&& (phase
!= PHASE_MSGOUT
)) {
1918 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(tmp
));
1920 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
|
1922 while (NCR5380_read(STATUS_REG
) & SR_REQ
)
1924 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1932 #if (NDEBUG & NDEBUG_NO_DATAOUT)
1933 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
1934 "aborted\n", HOSTNO
);
1937 cmd
->result
= DID_ERROR
<< 16;
1938 complete_cmd(instance
, cmd
);
1943 * If there is no room left in the current buffer in the
1944 * scatter-gather list, move onto the next one.
1947 if (!cmd
->SCp
.this_residual
&& cmd
->SCp
.buffers_residual
) {
1949 --cmd
->SCp
.buffers_residual
;
1950 cmd
->SCp
.this_residual
= cmd
->SCp
.buffer
->length
;
1951 cmd
->SCp
.ptr
= sg_virt(cmd
->SCp
.buffer
);
1952 /* ++roman: Try to merge some scatter-buffers if
1953 * they are at contiguous physical addresses.
1955 merge_contiguous_buffers(cmd
);
1956 dprintk(NDEBUG_INFORMATION
, "scsi%d: %d bytes and %d buffers left\n",
1957 HOSTNO
, cmd
->SCp
.this_residual
,
1958 cmd
->SCp
.buffers_residual
);
1962 * The preferred transfer method is going to be
1963 * PSEUDO-DMA for systems that are strictly PIO,
1964 * since we can let the hardware do the handshaking.
1966 * For this to work, we need to know the transfersize
1967 * ahead of time, since the pseudo-DMA code will sit
1968 * in an unconditional loop.
1971 /* ++roman: I suggest, this should be
1973 * instead of leaving REAL_DMA out.
1976 #if defined(REAL_DMA)
1977 #if !defined(CONFIG_SUN3)
1979 if (!cmd
->device
->borken
)
1981 transfersize
= NCR5380_dma_xfer_len(instance
, cmd
, phase
);
1983 if (transfersize
>= DMA_MIN_SIZE
) {
1985 cmd
->SCp
.phase
= phase
;
1986 if (NCR5380_transfer_dma(instance
, &phase
,
1987 &len
, (unsigned char **)&cmd
->SCp
.ptr
)) {
1989 * If the watchdog timer fires, all future
1990 * accesses to this device will use the
1992 scmd_printk(KERN_INFO
, cmd
,
1993 "switching to slow handshake\n");
1994 cmd
->device
->borken
= 1;
1997 cmd
->result
= DID_ERROR
<< 16;
1998 complete_cmd(instance
, cmd
);
1999 /* XXX - need to source or sink data here, as appropriate */
2002 /* ++roman: When using real DMA,
2003 * information_transfer() should return after
2004 * starting DMA since it has nothing more to
2009 cmd
->SCp
.this_residual
-= transfersize
- len
;
2013 #endif /* defined(REAL_DMA) */
2015 spin_unlock_irq(&hostdata
->lock
);
2016 NCR5380_transfer_pio(instance
, &phase
,
2017 (int *)&cmd
->SCp
.this_residual
,
2018 (unsigned char **)&cmd
->SCp
.ptr
);
2019 spin_lock_irq(&hostdata
->lock
);
2021 #if defined(CONFIG_SUN3) && defined(REAL_DMA)
2022 /* if we had intended to dma that command clear it */
2023 if (sun3_dma_setup_done
== cmd
)
2024 sun3_dma_setup_done
= NULL
;
2030 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2031 cmd
->SCp
.Message
= tmp
;
2035 case COMMAND_COMPLETE
:
2036 /* Accept message by clearing ACK */
2037 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2038 dsprintk(NDEBUG_QUEUES
, instance
,
2039 "COMMAND COMPLETE %p target %d lun %llu\n",
2040 cmd
, scmd_id(cmd
), cmd
->device
->lun
);
2042 hostdata
->connected
= NULL
;
2045 if (status_byte(cmd
->SCp
.Status
) == QUEUE_FULL
) {
2046 struct tag_alloc
*ta
= &hostdata
->TagAlloc
[scmd_id(cmd
)][cmd
->device
->lun
];
2047 dprintk(NDEBUG_TAGS
, "scsi%d: target %d lun %llu returned "
2048 "QUEUE_FULL after %d commands\n",
2049 HOSTNO
, cmd
->device
->id
, cmd
->device
->lun
,
2051 if (ta
->queue_size
> ta
->nr_allocated
)
2052 ta
->queue_size
= ta
->nr_allocated
;
2056 cmd
->result
&= ~0xffff;
2057 cmd
->result
|= cmd
->SCp
.Status
;
2058 cmd
->result
|= cmd
->SCp
.Message
<< 8;
2060 if (cmd
->cmnd
[0] == REQUEST_SENSE
)
2061 complete_cmd(instance
, cmd
);
2063 if (cmd
->SCp
.Status
== SAM_STAT_CHECK_CONDITION
||
2064 cmd
->SCp
.Status
== SAM_STAT_COMMAND_TERMINATED
) {
2065 dsprintk(NDEBUG_QUEUES
, instance
, "autosense: adding cmd %p to tail of autosense queue\n",
2067 list_add_tail(&ncmd
->list
,
2068 &hostdata
->autosense
);
2070 complete_cmd(instance
, cmd
);
2074 * Restore phase bits to 0 so an interrupted selection,
2075 * arbitration can resume.
2077 NCR5380_write(TARGET_COMMAND_REG
, 0);
2079 /* Enable reselect interrupts */
2080 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2082 /* ++roman: For Falcon SCSI, release the lock on the
2083 * ST-DMA here if no other commands are waiting on the
2084 * disconnected queue.
2086 maybe_release_dma_irq(instance
);
2088 case MESSAGE_REJECT
:
2089 /* Accept message by clearing ACK */
2090 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2091 switch (hostdata
->last_message
) {
2092 case HEAD_OF_QUEUE_TAG
:
2093 case ORDERED_QUEUE_TAG
:
2094 case SIMPLE_QUEUE_TAG
:
2095 /* The target obviously doesn't support tagged
2096 * queuing, even though it announced this ability in
2097 * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2098 * clear 'tagged_supported' and lock the LUN, since
2099 * the command is treated as untagged further on.
2101 cmd
->device
->tagged_supported
= 0;
2102 hostdata
->busy
[cmd
->device
->id
] |= (1 << cmd
->device
->lun
);
2103 cmd
->tag
= TAG_NONE
;
2104 dprintk(NDEBUG_TAGS
, "scsi%d: target %d lun %llu rejected "
2105 "QUEUE_TAG message; tagged queuing "
2107 HOSTNO
, cmd
->device
->id
, cmd
->device
->lun
);
2112 /* Accept message by clearing ACK */
2113 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2114 hostdata
->connected
= NULL
;
2115 list_add(&ncmd
->list
, &hostdata
->disconnected
);
2116 dsprintk(NDEBUG_INFORMATION
| NDEBUG_QUEUES
,
2117 instance
, "connected command %p for target %d lun %llu moved to disconnected queue\n",
2118 cmd
, scmd_id(cmd
), cmd
->device
->lun
);
2121 * Restore phase bits to 0 so an interrupted selection,
2122 * arbitration can resume.
2124 NCR5380_write(TARGET_COMMAND_REG
, 0);
2126 /* Enable reselect interrupts */
2127 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2128 #ifdef SUN3_SCSI_VME
2129 dregs
->csr
|= CSR_DMA_ENABLE
;
2133 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2134 * operation, in violation of the SCSI spec so we can safely
2135 * ignore SAVE/RESTORE pointers calls.
2137 * Unfortunately, some disks violate the SCSI spec and
2138 * don't issue the required SAVE_POINTERS message before
2139 * disconnecting, and we have to break spec to remain
2143 case RESTORE_POINTERS
:
2144 /* Accept message by clearing ACK */
2145 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2147 case EXTENDED_MESSAGE
:
2149 * Extended messages are sent in the following format :
2151 * 0 EXTENDED_MESSAGE == 1
2152 * 1 length (includes one byte for code, doesn't
2153 * include first two bytes)
2155 * 3..length+1 arguments
2157 * Start the extended message buffer with the EXTENDED_MESSAGE
2158 * byte, since spi_print_msg() wants the whole thing.
2160 extended_msg
[0] = EXTENDED_MESSAGE
;
2161 /* Accept first byte by clearing ACK */
2162 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2164 spin_unlock_irq(&hostdata
->lock
);
2166 dprintk(NDEBUG_EXTENDED
, "scsi%d: receiving extended message\n", HOSTNO
);
2169 data
= extended_msg
+ 1;
2170 phase
= PHASE_MSGIN
;
2171 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2172 dprintk(NDEBUG_EXTENDED
, "scsi%d: length=%d, code=0x%02x\n", HOSTNO
,
2173 (int)extended_msg
[1], (int)extended_msg
[2]);
2175 if (!len
&& extended_msg
[1] > 0 &&
2176 extended_msg
[1] <= sizeof(extended_msg
) - 2) {
2177 /* Accept third byte by clearing ACK */
2178 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2179 len
= extended_msg
[1] - 1;
2180 data
= extended_msg
+ 3;
2181 phase
= PHASE_MSGIN
;
2183 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2184 dprintk(NDEBUG_EXTENDED
, "scsi%d: message received, residual %d\n",
2187 switch (extended_msg
[2]) {
2190 case EXTENDED_MODIFY_DATA_POINTER
:
2191 case EXTENDED_EXTENDED_IDENTIFY
:
2195 printk(KERN_NOTICE
"scsi%d: error receiving "
2196 "extended message\n", HOSTNO
);
2199 printk(KERN_NOTICE
"scsi%d: extended message "
2200 "code %02x length %d is too long\n",
2201 HOSTNO
, extended_msg
[2], extended_msg
[1]);
2205 spin_lock_irq(&hostdata
->lock
);
2206 if (!hostdata
->connected
)
2209 /* Fall through to reject message */
2212 * If we get something weird that we aren't expecting,
2217 printk(KERN_INFO
"scsi%d: rejecting message ",
2219 spi_print_msg(extended_msg
);
2221 } else if (tmp
!= EXTENDED_MESSAGE
)
2222 scmd_printk(KERN_INFO
, cmd
,
2223 "rejecting unknown message %02x\n",
2226 scmd_printk(KERN_INFO
, cmd
,
2227 "rejecting unknown extended message code %02x, length %d\n",
2228 extended_msg
[1], extended_msg
[0]);
2230 msgout
= MESSAGE_REJECT
;
2231 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
2233 } /* switch (tmp) */
2238 hostdata
->last_message
= msgout
;
2239 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2240 if (msgout
== ABORT
) {
2241 hostdata
->connected
= NULL
;
2242 cmd
->result
= DID_ERROR
<< 16;
2243 complete_cmd(instance
, cmd
);
2244 maybe_release_dma_irq(instance
);
2245 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2254 * XXX for performance reasons, on machines with a
2255 * PSEUDO-DMA architecture we should probably
2256 * use the dma transfer function.
2258 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2263 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2264 cmd
->SCp
.Status
= tmp
;
2267 printk("scsi%d: unknown phase\n", HOSTNO
);
2268 NCR5380_dprint(NDEBUG_ANY
, instance
);
2269 } /* switch(phase) */
2271 spin_unlock_irq(&hostdata
->lock
);
2272 NCR5380_poll_politely(instance
, STATUS_REG
, SR_REQ
, SR_REQ
, HZ
);
2273 spin_lock_irq(&hostdata
->lock
);
2279 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2281 * Purpose : does reselection, initializing the instance->connected
2282 * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
2283 * nexus has been reestablished,
2285 * Inputs : instance - this instance of the NCR5380.
2290 /* it might eventually prove necessary to do a dma setup on
2291 reselection, but it doesn't seem to be needed now -- sam */
2293 static void NCR5380_reselect(struct Scsi_Host
*instance
)
2295 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
2296 unsigned char target_mask
;
2301 unsigned char msg
[3];
2302 int __maybe_unused len
;
2303 unsigned char __maybe_unused
*data
, __maybe_unused phase
;
2304 struct NCR5380_cmd
*ncmd
;
2305 struct scsi_cmnd
*tmp
;
2308 * Disable arbitration, etc. since the host adapter obviously
2309 * lost, and tell an interrupted NCR5380_select() to restart.
2312 NCR5380_write(MODE_REG
, MR_BASE
);
2314 target_mask
= NCR5380_read(CURRENT_SCSI_DATA_REG
) & ~(hostdata
->id_mask
);
2316 dprintk(NDEBUG_RESELECTION
, "scsi%d: reselect\n", HOSTNO
);
2319 * At this point, we have detected that our SCSI ID is on the bus,
2320 * SEL is true and BSY was false for at least one bus settle delay
2323 * We must assert BSY ourselves, until the target drops the SEL
2327 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_BSY
);
2328 if (NCR5380_poll_politely(instance
,
2329 STATUS_REG
, SR_SEL
, 0, 2 * HZ
) < 0) {
2330 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2333 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2336 * Wait for target to go into MSGIN.
2339 if (NCR5380_poll_politely(instance
,
2340 STATUS_REG
, SR_REQ
, SR_REQ
, 2 * HZ
) < 0) {
2345 #if defined(CONFIG_SUN3) && defined(REAL_DMA)
2346 /* acknowledge toggle to MSGIN */
2347 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(PHASE_MSGIN
));
2349 /* peek at the byte without really hitting the bus */
2350 msg
[0] = NCR5380_read(CURRENT_SCSI_DATA_REG
);
2354 phase
= PHASE_MSGIN
;
2355 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2363 if (!(msg
[0] & 0x80)) {
2364 shost_printk(KERN_ERR
, instance
, "expecting IDENTIFY message, got ");
2370 lun
= msg
[0] & 0x07;
2372 #if defined(SUPPORT_TAGS) && !defined(CONFIG_SUN3)
2373 /* If the phase is still MSGIN, the target wants to send some more
2374 * messages. In case it supports tagged queuing, this is probably a
2375 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2378 if (phase
== PHASE_MSGIN
&& (hostdata
->flags
& FLAG_TAGGED_QUEUING
)) {
2379 /* Accept previous IDENTIFY message by clearing ACK */
2380 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2383 if (!NCR5380_transfer_pio(instance
, &phase
, &len
, &data
) &&
2384 msg
[1] == SIMPLE_QUEUE_TAG
)
2386 dprintk(NDEBUG_TAGS
, "scsi%d: target mask %02x, lun %d sent tag %d at "
2387 "reselection\n", HOSTNO
, target_mask
, lun
, tag
);
2392 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2393 * just reestablished, and remove it from the disconnected queue.
2397 list_for_each_entry(ncmd
, &hostdata
->disconnected
, list
) {
2398 struct scsi_cmnd
*cmd
= NCR5380_to_scmd(ncmd
);
2400 if (target_mask
== (1 << scmd_id(cmd
)) &&
2401 lun
== (u8
)cmd
->device
->lun
2403 && (tag
== cmd
->tag
)
2406 list_del(&ncmd
->list
);
2413 dsprintk(NDEBUG_RESELECTION
| NDEBUG_QUEUES
, instance
,
2414 "reselect: removed %p from disconnected queue\n", tmp
);
2418 shost_printk(KERN_ERR
, instance
, "target bitmask 0x%02x lun %d tag %d not in disconnected queue.\n",
2419 target_mask
, lun
, tag
);
2421 shost_printk(KERN_ERR
, instance
, "target bitmask 0x%02x lun %d not in disconnected queue.\n",
2425 * Since we have an established nexus that we can't do anything
2426 * with, we must abort it.
2432 #if defined(CONFIG_SUN3) && defined(REAL_DMA)
2433 /* engage dma setup for the command we just saw */
2436 unsigned long count
;
2438 if (!tmp
->SCp
.this_residual
&& tmp
->SCp
.buffers_residual
) {
2439 count
= tmp
->SCp
.buffer
->length
;
2440 d
= sg_virt(tmp
->SCp
.buffer
);
2442 count
= tmp
->SCp
.this_residual
;
2445 /* setup this command for dma if not already */
2446 if ((count
>= DMA_MIN_SIZE
) && (sun3_dma_setup_done
!= tmp
)) {
2447 sun3scsi_dma_setup(d
, count
, rq_data_dir(tmp
->request
));
2448 sun3_dma_setup_done
= tmp
;
2452 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ACK
);
2455 /* Accept message by clearing ACK */
2456 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2458 #if defined(SUPPORT_TAGS) && defined(CONFIG_SUN3)
2459 /* If the phase is still MSGIN, the target wants to send some more
2460 * messages. In case it supports tagged queuing, this is probably a
2461 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2464 if (phase
== PHASE_MSGIN
&& setup_use_tagged_queuing
) {
2465 /* Accept previous IDENTIFY message by clearing ACK */
2466 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2469 if (!NCR5380_transfer_pio(instance
, &phase
, &len
, &data
) &&
2470 msg
[1] == SIMPLE_QUEUE_TAG
)
2472 dprintk(NDEBUG_TAGS
, "scsi%d: target mask %02x, lun %d sent tag %d at reselection\n"
2473 HOSTNO
, target_mask
, lun
, tag
);
2477 hostdata
->connected
= tmp
;
2478 dprintk(NDEBUG_RESELECTION
, "scsi%d: nexus established, target = %d, lun = %llu, tag = %d\n",
2479 HOSTNO
, tmp
->device
->id
, tmp
->device
->lun
, tmp
->tag
);
2484 * Function : int NCR5380_abort (struct scsi_cmnd *cmd)
2486 * Purpose : abort a command
2488 * Inputs : cmd - the scsi_cmnd to abort, code - code to set the
2489 * host byte of the result field to, if zero DID_ABORTED is
2492 * Returns : SUCCESS - success, FAILED on failure.
2494 * XXX - there is no way to abort the command that is currently
2495 * connected, you have to wait for it to complete. If this is
2496 * a problem, we could implement longjmp() / setjmp(), setjmp()
2497 * called where the loop started in NCR5380_main().
2501 int NCR5380_abort(struct scsi_cmnd
*cmd
)
2503 struct Scsi_Host
*instance
= cmd
->device
->host
;
2504 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
2505 unsigned long flags
;
2507 spin_lock_irqsave(&hostdata
->lock
, flags
);
2509 #if (NDEBUG & NDEBUG_ANY)
2510 scmd_printk(KERN_INFO
, cmd
, "aborting command\n");
2512 NCR5380_dprint(NDEBUG_ANY
, instance
);
2513 NCR5380_dprint_phase(NDEBUG_ANY
, instance
);
2515 spin_unlock_irqrestore(&hostdata
->lock
, flags
);
2522 * NCR5380_bus_reset - reset the SCSI bus
2523 * @cmd: SCSI command undergoing EH
2528 static int NCR5380_bus_reset(struct scsi_cmnd
*cmd
)
2530 struct Scsi_Host
*instance
= cmd
->device
->host
;
2531 struct NCR5380_hostdata
*hostdata
= shost_priv(instance
);
2533 unsigned long flags
;
2535 spin_lock_irqsave(&hostdata
->lock
, flags
);
2537 #if (NDEBUG & NDEBUG_ANY)
2538 scmd_printk(KERN_INFO
, cmd
, "performing bus reset\n");
2540 NCR5380_dprint(NDEBUG_ANY
, instance
);
2541 NCR5380_dprint_phase(NDEBUG_ANY
, instance
);
2545 /* reset NCR registers */
2546 NCR5380_write(MODE_REG
, MR_BASE
);
2547 NCR5380_write(TARGET_COMMAND_REG
, 0);
2548 NCR5380_write(SELECT_ENABLE_REG
, 0);
2550 /* After the reset, there are no more connected or disconnected commands
2551 * and no busy units; so clear the low-level status here to avoid
2552 * conflicts when the mid-level code tries to wake up the affected
2556 if (hostdata
->connected
)
2557 dsprintk(NDEBUG_ABORT
, instance
, "reset aborted a connected command\n");
2558 hostdata
->connected
= NULL
;
2560 if (hostdata
->sensing
) {
2561 complete_cmd(instance
, hostdata
->sensing
);
2562 hostdata
->sensing
= NULL
;
2565 if (!list_empty(&hostdata
->autosense
))
2566 dsprintk(NDEBUG_ABORT
, instance
, "reset aborted autosense list\n");
2567 INIT_LIST_HEAD(&hostdata
->autosense
);
2569 if (!list_empty(&hostdata
->unissued
))
2570 dsprintk(NDEBUG_ABORT
, instance
, "reset aborted unissued list\n");
2571 INIT_LIST_HEAD(&hostdata
->unissued
);
2573 if (!list_empty(&hostdata
->disconnected
))
2574 dsprintk(NDEBUG_ABORT
, instance
, "reset aborted disconnected list\n");
2575 INIT_LIST_HEAD(&hostdata
->disconnected
);
2578 free_all_tags(hostdata
);
2580 for (i
= 0; i
< 8; ++i
)
2581 hostdata
->busy
[i
] = 0;
2583 hostdata
->dma_len
= 0;
2586 maybe_release_dma_irq(instance
);
2587 spin_unlock_irqrestore(&hostdata
->lock
, flags
);