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 * DISTRIBUTION RELEASE 6.
16 * For more information, please consult
19 * SCSI Protocol Controller
22 * NCR Microelectronics
23 * 1635 Aeroplaza Drive
24 * Colorado Springs, CO 80916
30 * ++roman: To port the 5380 driver to the Atari, I had to do some changes in
33 * - Some of the debug statements were incorrect (undefined variables and the
34 * like). I fixed that.
36 * - In information_transfer(), I think a #ifdef was wrong. Looking at the
37 * possible DMA transfer size should also happen for REAL_DMA. I added this
38 * in the #if statement.
40 * - When using real DMA, information_transfer() should return in a DATAOUT
41 * phase after starting the DMA. It has nothing more to do.
43 * - The interrupt service routine should run main after end of DMA, too (not
44 * only after RESELECTION interrupts). Additionally, it should _not_ test
45 * for more interrupts after running main, since a DMA process may have
46 * been started and interrupts are turned on now. The new int could happen
47 * inside the execution of NCR5380_intr(), leading to recursive
50 * - I've added a function merge_contiguous_buffers() that tries to
51 * merge scatter-gather buffers that are located at contiguous
52 * physical addresses and can be processed with the same DMA setup.
53 * Since most scatter-gather operations work on a page (4K) of
54 * 4 buffers (1K), in more than 90% of all cases three interrupts and
55 * DMA setup actions are saved.
57 * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA
58 * and USLEEP, because these were messing up readability and will never be
59 * needed for Atari SCSI.
61 * - I've revised the NCR5380_main() calling scheme (relax the 'main_running'
62 * stuff), and 'main' is executed in a bottom half if awoken by an
65 * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..."
66 * constructs. In my eyes, this made the source rather unreadable, so I
67 * finally replaced that by the *_PRINTK() macros.
72 * Further development / testing that should be done :
73 * 1. Test linked command handling code after Eric is ready with
74 * the high level code.
76 #include <scsi/scsi_dbg.h>
77 #include <scsi/scsi_transport_spi.h>
79 #if (NDEBUG & NDEBUG_LISTS)
82 printk("LINE:%d Adding %p to %p\n", \
83 __LINE__, (void*)(x), (void*)(y)); \
87 #define REMOVE(w, x, y, z) \
89 printk("LINE:%d Removing: %p->%p %p->%p \n", \
90 __LINE__, (void*)(w), (void*)(x), \
91 (void*)(y), (void*)(z)); \
97 #define REMOVE(w,x,y,z)
108 * The other Linux SCSI drivers were written when Linux was Intel PC-only,
109 * and specifically for each board rather than each chip. This makes their
110 * adaptation to platforms like the Mac (Some of which use NCR5380's)
111 * more difficult than it has to be.
113 * Also, many of the SCSI drivers were written before the command queuing
114 * routines were implemented, meaning their implementations of queued
115 * commands were hacked on rather than designed in from the start.
117 * When I designed the Linux SCSI drivers I figured that
118 * while having two different SCSI boards in a system might be useful
119 * for debugging things, two of the same type wouldn't be used.
120 * Well, I was wrong and a number of users have mailed me about running
121 * multiple high-performance SCSI boards in a server.
123 * Finally, when I get questions from users, I have no idea what
124 * revision of my driver they are running.
126 * This driver attempts to address these problems :
127 * This is a generic 5380 driver. To use it on a different platform,
128 * one simply writes appropriate system specific macros (ie, data
129 * transfer - some PC's will use the I/O bus, 68K's must use
130 * memory mapped) and drops this file in their 'C' wrapper.
132 * As far as command queueing, two queues are maintained for
133 * each 5380 in the system - commands that haven't been issued yet,
134 * and commands that are currently executing. This means that an
135 * unlimited number of commands may be queued, letting
136 * more commands propagate from the higher driver levels giving higher
137 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
138 * allowing multiple commands to propagate all the way to a SCSI-II device
139 * while a command is already executing.
141 * To solve the multiple-boards-in-the-same-system problem,
142 * there is a separate instance structure for each instance
143 * of a 5380 in the system. So, multiple NCR5380 drivers will
144 * be able to coexist with appropriate changes to the high level
147 * A NCR5380_PUBLIC_REVISION macro is provided, with the release
148 * number (updated for each public release) printed by the
149 * NCR5380_print_options command, which should be called from the
150 * wrapper detect function, so that I know what release of the driver
153 * Issues specific to the NCR5380 :
155 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
156 * piece of hardware that requires you to sit in a loop polling for
157 * the REQ signal as long as you are connected. Some devices are
158 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
159 * while doing long seek operations.
161 * The workaround for this is to keep track of devices that have
162 * disconnected. If the device hasn't disconnected, for commands that
163 * should disconnect, we do something like
165 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
167 * Some tweaking of N and M needs to be done. An algorithm based
168 * on "time to data" would give the best results as long as short time
169 * to datas (ie, on the same track) were considered, however these
170 * broken devices are the exception rather than the rule and I'd rather
171 * spend my time optimizing for the normal case.
175 * At the heart of the design is a coroutine, NCR5380_main,
176 * which is started when not running by the interrupt handler,
177 * timer, and queue command function. It attempts to establish
178 * I_T_L or I_T_L_Q nexuses by removing the commands from the
179 * issue queue and calling NCR5380_select() if a nexus
180 * is not established.
182 * Once a nexus is established, the NCR5380_information_transfer()
183 * phase goes through the various phases as instructed by the target.
184 * if the target goes into MSG IN and sends a DISCONNECT message,
185 * the command structure is placed into the per instance disconnected
186 * queue, and NCR5380_main tries to find more work. If USLEEP
187 * was defined, and the target is idle for too long, the system
190 * If a command has disconnected, eventually an interrupt will trigger,
191 * calling NCR5380_intr() which will in turn call NCR5380_reselect
192 * to reestablish a nexus. This will run main if necessary.
194 * On command termination, the done function will be called as
197 * SCSI pointers are maintained in the SCp field of SCSI command
198 * structures, being initialized after the command is connected
199 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
200 * Note that in violation of the standard, an implicit SAVE POINTERS operation
201 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
206 * This file a skeleton Linux SCSI driver for the NCR 5380 series
207 * of chips. To use it, you write an architecture specific functions
208 * and macros and include this file in your driver.
210 * These macros control options :
211 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
212 * for commands that return with a CHECK CONDITION status.
214 * LINKED - if defined, linked commands are supported.
216 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
218 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
220 * These macros MUST be defined :
222 * NCR5380_read(register) - read from the specified register
224 * NCR5380_write(register, value) - write to the specific register
226 * Either real DMA *or* pseudo DMA may be implemented
228 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
229 * Note that the DMA setup functions should return the number of bytes
230 * that they were able to program the controller for.
232 * Also note that generic i386/PC versions of these macros are
233 * available as NCR5380_i386_dma_write_setup,
234 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
236 * NCR5380_dma_write_setup(instance, src, count) - initialize
237 * NCR5380_dma_read_setup(instance, dst, count) - initialize
238 * NCR5380_dma_residual(instance); - residual count
241 * NCR5380_pwrite(instance, src, count)
242 * NCR5380_pread(instance, dst, count);
244 * If nothing specific to this implementation needs doing (ie, with external
245 * hardware), you must also define
247 * NCR5380_queue_command
252 * to be the global entry points into the specific driver, ie
253 * #define NCR5380_queue_command t128_queue_command.
255 * If this is not done, the routines will be defined as static functions
256 * with the NCR5380* names and the user must provide a globally
257 * accessible wrapper function.
259 * The generic driver is initialized by calling NCR5380_init(instance),
260 * after setting the appropriate host specific fields and ID. If the
261 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
262 * possible) function may be used. Before the specific driver initialization
263 * code finishes, NCR5380_print_options should be called.
266 static struct Scsi_Host
*first_instance
= NULL
;
267 static struct scsi_host_template
*the_template
= NULL
;
269 /* Macros ease life... :-) */
270 #define SETUP_HOSTDATA(in) \
271 struct NCR5380_hostdata *hostdata = \
272 (struct NCR5380_hostdata *)(in)->hostdata
273 #define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)
275 #define NEXT(cmd) ((Scsi_Cmnd *)(cmd)->host_scribble)
276 #define SET_NEXT(cmd,next) ((cmd)->host_scribble = (void *)(next))
277 #define NEXTADDR(cmd) ((Scsi_Cmnd **)&(cmd)->host_scribble)
279 #define HOSTNO instance->host_no
280 #define H_NO(cmd) (cmd)->device->host->host_no
285 * Functions for handling tagged queuing
286 * =====================================
288 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
290 * Using consecutive numbers for the tags is no good idea in my eyes. There
291 * could be wrong re-usings if the counter (8 bit!) wraps and some early
292 * command has been preempted for a long time. My solution: a bitfield for
293 * remembering used tags.
295 * There's also the problem that each target has a certain queue size, but we
296 * cannot know it in advance :-( We just see a QUEUE_FULL status being
297 * returned. So, in this case, the driver internal queue size assumption is
298 * reduced to the number of active tags if QUEUE_FULL is returned by the
299 * target. The command is returned to the mid-level, but with status changed
300 * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL
303 * We're also not allowed running tagged commands as long as an untagged
304 * command is active. And REQUEST SENSE commands after a contingent allegiance
305 * condition _must_ be untagged. To keep track whether an untagged command has
306 * been issued, the host->busy array is still employed, as it is without
307 * support for tagged queuing.
309 * One could suspect that there are possible race conditions between
310 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
311 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
312 * which already guaranteed to be running at most once. It is also the only
313 * place where tags/LUNs are allocated. So no other allocation can slip
314 * between that pair, there could only happen a reselection, which can free a
315 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
316 * important: the tag bit must be cleared before 'nr_allocated' is decreased.
319 /* -1 for TAG_NONE is not possible with unsigned char cmd->tag */
321 #define TAG_NONE 0xff
324 DECLARE_BITMAP(allocated
, MAX_TAGS
);
329 static TAG_ALLOC TagAlloc
[8][8]; /* 8 targets and 8 LUNs */
332 static void __init
init_tags(void)
337 if (!setup_use_tagged_queuing
)
340 for (target
= 0; target
< 8; ++target
) {
341 for (lun
= 0; lun
< 8; ++lun
) {
342 ta
= &TagAlloc
[target
][lun
];
343 bitmap_zero(ta
->allocated
, MAX_TAGS
);
344 ta
->nr_allocated
= 0;
345 /* At the beginning, assume the maximum queue size we could
346 * support (MAX_TAGS). This value will be decreased if the target
347 * returns QUEUE_FULL status.
349 ta
->queue_size
= MAX_TAGS
;
355 /* Check if we can issue a command to this LUN: First see if the LUN is marked
356 * busy by an untagged command. If the command should use tagged queuing, also
357 * check that there is a free tag and the target's queue won't overflow. This
358 * function should be called with interrupts disabled to avoid race
362 static int is_lun_busy(Scsi_Cmnd
*cmd
, int should_be_tagged
)
364 SETUP_HOSTDATA(cmd
->device
->host
);
366 if (hostdata
->busy
[cmd
->device
->id
] & (1 << cmd
->device
->lun
))
368 if (!should_be_tagged
||
369 !setup_use_tagged_queuing
|| !cmd
->device
->tagged_supported
)
371 if (TagAlloc
[cmd
->device
->id
][cmd
->device
->lun
].nr_allocated
>=
372 TagAlloc
[cmd
->device
->id
][cmd
->device
->lun
].queue_size
) {
373 dprintk(NDEBUG_TAGS
, "scsi%d: target %d lun %d: no free tags\n",
374 H_NO(cmd
), cmd
->device
->id
, cmd
->device
->lun
);
381 /* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
382 * must be called before!), or reserve the LUN in 'busy' if the command is
386 static void cmd_get_tag(Scsi_Cmnd
*cmd
, int should_be_tagged
)
388 SETUP_HOSTDATA(cmd
->device
->host
);
390 /* If we or the target don't support tagged queuing, allocate the LUN for
391 * an untagged command.
393 if (!should_be_tagged
||
394 !setup_use_tagged_queuing
|| !cmd
->device
->tagged_supported
) {
396 hostdata
->busy
[cmd
->device
->id
] |= (1 << cmd
->device
->lun
);
397 dprintk(NDEBUG_TAGS
, "scsi%d: target %d lun %d now allocated by untagged "
398 "command\n", H_NO(cmd
), cmd
->device
->id
, cmd
->device
->lun
);
400 TAG_ALLOC
*ta
= &TagAlloc
[cmd
->device
->id
][cmd
->device
->lun
];
402 cmd
->tag
= find_first_zero_bit(ta
->allocated
, MAX_TAGS
);
403 set_bit(cmd
->tag
, ta
->allocated
);
405 dprintk(NDEBUG_TAGS
, "scsi%d: using tag %d for target %d lun %d "
406 "(now %d tags in use)\n",
407 H_NO(cmd
), cmd
->tag
, cmd
->device
->id
,
408 cmd
->device
->lun
, ta
->nr_allocated
);
413 /* Mark the tag of command 'cmd' as free, or in case of an untagged command,
417 static void cmd_free_tag(Scsi_Cmnd
*cmd
)
419 SETUP_HOSTDATA(cmd
->device
->host
);
421 if (cmd
->tag
== TAG_NONE
) {
422 hostdata
->busy
[cmd
->device
->id
] &= ~(1 << cmd
->device
->lun
);
423 dprintk(NDEBUG_TAGS
, "scsi%d: target %d lun %d untagged cmd finished\n",
424 H_NO(cmd
), cmd
->device
->id
, cmd
->device
->lun
);
425 } else if (cmd
->tag
>= MAX_TAGS
) {
426 printk(KERN_NOTICE
"scsi%d: trying to free bad tag %d!\n",
427 H_NO(cmd
), cmd
->tag
);
429 TAG_ALLOC
*ta
= &TagAlloc
[cmd
->device
->id
][cmd
->device
->lun
];
430 clear_bit(cmd
->tag
, ta
->allocated
);
432 dprintk(NDEBUG_TAGS
, "scsi%d: freed tag %d for target %d lun %d\n",
433 H_NO(cmd
), cmd
->tag
, cmd
->device
->id
, cmd
->device
->lun
);
438 static void free_all_tags(void)
443 if (!setup_use_tagged_queuing
)
446 for (target
= 0; target
< 8; ++target
) {
447 for (lun
= 0; lun
< 8; ++lun
) {
448 ta
= &TagAlloc
[target
][lun
];
449 bitmap_zero(ta
->allocated
, MAX_TAGS
);
450 ta
->nr_allocated
= 0;
455 #endif /* SUPPORT_TAGS */
459 * Function: void merge_contiguous_buffers( Scsi_Cmnd *cmd )
461 * Purpose: Try to merge several scatter-gather requests into one DMA
462 * transfer. This is possible if the scatter buffers lie on
463 * physical contiguous addresses.
465 * Parameters: Scsi_Cmnd *cmd
466 * The command to work on. The first scatter buffer's data are
467 * assumed to be already transferred into ptr/this_residual.
470 static void merge_contiguous_buffers(Scsi_Cmnd
*cmd
)
472 unsigned long endaddr
;
473 #if (NDEBUG & NDEBUG_MERGING)
474 unsigned long oldlen
= cmd
->SCp
.this_residual
;
478 for (endaddr
= virt_to_phys(cmd
->SCp
.ptr
+ cmd
->SCp
.this_residual
- 1) + 1;
479 cmd
->SCp
.buffers_residual
&&
480 virt_to_phys(sg_virt(&cmd
->SCp
.buffer
[1])) == endaddr
;) {
481 dprintk(NDEBUG_MERGING
, "VTOP(%p) == %08lx -> merging\n",
482 page_address(sg_page(&cmd
->SCp
.buffer
[1])), endaddr
);
483 #if (NDEBUG & NDEBUG_MERGING)
487 --cmd
->SCp
.buffers_residual
;
488 cmd
->SCp
.this_residual
+= cmd
->SCp
.buffer
->length
;
489 endaddr
+= cmd
->SCp
.buffer
->length
;
491 #if (NDEBUG & NDEBUG_MERGING)
492 if (oldlen
!= cmd
->SCp
.this_residual
)
493 dprintk(NDEBUG_MERGING
, "merged %d buffers from %p, new length %08x\n",
494 cnt
, cmd
->SCp
.ptr
, cmd
->SCp
.this_residual
);
499 * Function : void initialize_SCp(Scsi_Cmnd *cmd)
501 * Purpose : initialize the saved data pointers for cmd to point to the
502 * start of the buffer.
504 * Inputs : cmd - Scsi_Cmnd structure to have pointers reset.
507 static inline void initialize_SCp(Scsi_Cmnd
*cmd
)
510 * Initialize the Scsi Pointer field so that all of the commands in the
511 * various queues are valid.
514 if (scsi_bufflen(cmd
)) {
515 cmd
->SCp
.buffer
= scsi_sglist(cmd
);
516 cmd
->SCp
.buffers_residual
= scsi_sg_count(cmd
) - 1;
517 cmd
->SCp
.ptr
= sg_virt(cmd
->SCp
.buffer
);
518 cmd
->SCp
.this_residual
= cmd
->SCp
.buffer
->length
;
519 /* ++roman: Try to merge some scatter-buffers if they are at
520 * contiguous physical addresses.
522 merge_contiguous_buffers(cmd
);
524 cmd
->SCp
.buffer
= NULL
;
525 cmd
->SCp
.buffers_residual
= 0;
527 cmd
->SCp
.this_residual
= 0;
531 #include <linux/delay.h>
538 { SR_DBP
, "PARITY"}, { SR_RST
, "RST" }, { SR_BSY
, "BSY" },
539 { SR_REQ
, "REQ" }, { SR_MSG
, "MSG" }, { SR_CD
, "CD" }, { SR_IO
, "IO" },
540 { SR_SEL
, "SEL" }, {0, NULL
}
542 {BASR_ATN
, "ATN"}, {BASR_ACK
, "ACK"}, {0, NULL
}
544 {ICR_ASSERT_RST
, "ASSERT RST"},{ICR_ASSERT_ACK
, "ASSERT ACK"},
545 {ICR_ASSERT_BSY
, "ASSERT BSY"}, {ICR_ASSERT_SEL
, "ASSERT SEL"},
546 {ICR_ASSERT_ATN
, "ASSERT ATN"}, {ICR_ASSERT_DATA
, "ASSERT DATA"},
549 {MR_BLOCK_DMA_MODE
, "MODE BLOCK DMA"}, {MR_TARGET
, "MODE TARGET"},
550 {MR_ENABLE_PAR_CHECK
, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR
,
551 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR
,"MODE EOP INTR"},
552 {MR_MONITOR_BSY
, "MODE MONITOR BSY"},
553 {MR_DMA_MODE
, "MODE DMA"}, {MR_ARBITRATE
, "MODE ARBITRATION"},
558 * Function : void NCR5380_print(struct Scsi_Host *instance)
560 * Purpose : print the SCSI bus signals for debugging purposes
562 * Input : instance - which NCR5380
565 static void NCR5380_print(struct Scsi_Host
*instance
)
567 unsigned char status
, data
, basr
, mr
, icr
, i
;
570 local_irq_save(flags
);
571 data
= NCR5380_read(CURRENT_SCSI_DATA_REG
);
572 status
= NCR5380_read(STATUS_REG
);
573 mr
= NCR5380_read(MODE_REG
);
574 icr
= NCR5380_read(INITIATOR_COMMAND_REG
);
575 basr
= NCR5380_read(BUS_AND_STATUS_REG
);
576 local_irq_restore(flags
);
577 printk("STATUS_REG: %02x ", status
);
578 for (i
= 0; signals
[i
].mask
; ++i
)
579 if (status
& signals
[i
].mask
)
580 printk(",%s", signals
[i
].name
);
581 printk("\nBASR: %02x ", basr
);
582 for (i
= 0; basrs
[i
].mask
; ++i
)
583 if (basr
& basrs
[i
].mask
)
584 printk(",%s", basrs
[i
].name
);
585 printk("\nICR: %02x ", icr
);
586 for (i
= 0; icrs
[i
].mask
; ++i
)
587 if (icr
& icrs
[i
].mask
)
588 printk(",%s", icrs
[i
].name
);
589 printk("\nMODE: %02x ", mr
);
590 for (i
= 0; mrs
[i
].mask
; ++i
)
591 if (mr
& mrs
[i
].mask
)
592 printk(",%s", mrs
[i
].name
);
600 {PHASE_DATAOUT
, "DATAOUT"}, {PHASE_DATAIN
, "DATAIN"}, {PHASE_CMDOUT
, "CMDOUT"},
601 {PHASE_STATIN
, "STATIN"}, {PHASE_MSGOUT
, "MSGOUT"}, {PHASE_MSGIN
, "MSGIN"},
602 {PHASE_UNKNOWN
, "UNKNOWN"}
606 * Function : void NCR5380_print_phase(struct Scsi_Host *instance)
608 * Purpose : print the current SCSI phase for debugging purposes
610 * Input : instance - which NCR5380
613 static void NCR5380_print_phase(struct Scsi_Host
*instance
)
615 unsigned char status
;
618 status
= NCR5380_read(STATUS_REG
);
619 if (!(status
& SR_REQ
))
620 printk(KERN_DEBUG
"scsi%d: REQ not asserted, phase unknown.\n", HOSTNO
);
622 for (i
= 0; (phases
[i
].value
!= PHASE_UNKNOWN
) &&
623 (phases
[i
].value
!= (status
& PHASE_MASK
)); ++i
)
625 printk(KERN_DEBUG
"scsi%d: phase %s\n", HOSTNO
, phases
[i
].name
);
632 * ++roman: New scheme of calling NCR5380_main()
634 * If we're not in an interrupt, we can call our main directly, it cannot be
635 * already running. Else, we queue it on a task queue, if not 'main_running'
636 * tells us that a lower level is already executing it. This way,
637 * 'main_running' needs not be protected in a special way.
639 * queue_main() is a utility function for putting our main onto the task
640 * queue, if main_running is false. It should be called only from a
641 * interrupt or bottom half.
644 #include <linux/gfp.h>
645 #include <linux/workqueue.h>
646 #include <linux/interrupt.h>
648 static volatile int main_running
;
649 static DECLARE_WORK(NCR5380_tqueue
, NCR5380_main
);
651 static inline void queue_main(void)
654 /* If in interrupt and NCR5380_main() not already running,
655 queue it on the 'immediate' task queue, to be processed
656 immediately after the current interrupt processing has
658 schedule_work(&NCR5380_tqueue
);
660 /* else: nothing to do: the running NCR5380_main() will pick up
661 any newly queued command. */
665 static inline void NCR5380_all_init(void)
669 dprintk(NDEBUG_INIT
, "scsi : NCR5380_all_init()\n");
676 * Function : void NCR58380_print_options (struct Scsi_Host *instance)
678 * Purpose : called by probe code indicating the NCR5380 driver
679 * options that were selected.
681 * Inputs : instance, pointer to this instance. Unused.
684 static void __init
NCR5380_print_options(struct Scsi_Host
*instance
)
686 printk(" generic options"
697 " SCSI-2 TAGGED QUEUING"
700 printk(" generic release=%d", NCR5380_PUBLIC_RELEASE
);
704 * Function : void NCR5380_print_status (struct Scsi_Host *instance)
706 * Purpose : print commands in the various queues, called from
707 * NCR5380_abort and NCR5380_debug to aid debugging.
709 * Inputs : instance, pointer to this instance.
712 static void lprint_Scsi_Cmnd(Scsi_Cmnd
*cmd
)
715 unsigned char *command
;
716 printk("scsi%d: destination target %d, lun %d\n",
717 H_NO(cmd
), cmd
->device
->id
, cmd
->device
->lun
);
718 printk(KERN_CONT
" command = ");
720 printk(KERN_CONT
"%2d (0x%02x)", command
[0], command
[0]);
721 for (i
= 1, s
= COMMAND_SIZE(command
[0]); i
< s
; ++i
)
722 printk(KERN_CONT
" %02x", command
[i
]);
726 static void NCR5380_print_status(struct Scsi_Host
*instance
)
728 struct NCR5380_hostdata
*hostdata
;
732 NCR5380_dprint(NDEBUG_ANY
, instance
);
733 NCR5380_dprint_phase(NDEBUG_ANY
, instance
);
735 hostdata
= (struct NCR5380_hostdata
*)instance
->hostdata
;
737 printk("\nNCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE
);
738 local_irq_save(flags
);
739 printk("NCR5380: coroutine is%s running.\n",
740 main_running
? "" : "n't");
741 if (!hostdata
->connected
)
742 printk("scsi%d: no currently connected command\n", HOSTNO
);
744 lprint_Scsi_Cmnd((Scsi_Cmnd
*) hostdata
->connected
);
745 printk("scsi%d: issue_queue\n", HOSTNO
);
746 for (ptr
= (Scsi_Cmnd
*)hostdata
->issue_queue
; ptr
; ptr
= NEXT(ptr
))
747 lprint_Scsi_Cmnd(ptr
);
749 printk("scsi%d: disconnected_queue\n", HOSTNO
);
750 for (ptr
= (Scsi_Cmnd
*) hostdata
->disconnected_queue
; ptr
;
752 lprint_Scsi_Cmnd(ptr
);
754 local_irq_restore(flags
);
758 static void show_Scsi_Cmnd(Scsi_Cmnd
*cmd
, struct seq_file
*m
)
761 unsigned char *command
;
762 seq_printf(m
, "scsi%d: destination target %d, lun %d\n",
763 H_NO(cmd
), cmd
->device
->id
, cmd
->device
->lun
);
764 seq_printf(m
, " command = ");
766 seq_printf(m
, "%2d (0x%02x)", command
[0], command
[0]);
767 for (i
= 1, s
= COMMAND_SIZE(command
[0]); i
< s
; ++i
)
768 seq_printf(m
, " %02x", command
[i
]);
772 static int NCR5380_show_info(struct seq_file
*m
, struct Scsi_Host
*instance
)
774 struct NCR5380_hostdata
*hostdata
;
778 hostdata
= (struct NCR5380_hostdata
*)instance
->hostdata
;
780 seq_printf(m
, "NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE
);
781 local_irq_save(flags
);
782 seq_printf(m
, "NCR5380: coroutine is%s running.\n",
783 main_running
? "" : "n't");
784 if (!hostdata
->connected
)
785 seq_printf(m
, "scsi%d: no currently connected command\n", HOSTNO
);
787 show_Scsi_Cmnd((Scsi_Cmnd
*) hostdata
->connected
, m
);
788 seq_printf(m
, "scsi%d: issue_queue\n", HOSTNO
);
789 for (ptr
= (Scsi_Cmnd
*)hostdata
->issue_queue
; ptr
; ptr
= NEXT(ptr
))
790 show_Scsi_Cmnd(ptr
, m
);
792 seq_printf(m
, "scsi%d: disconnected_queue\n", HOSTNO
);
793 for (ptr
= (Scsi_Cmnd
*) hostdata
->disconnected_queue
; ptr
;
795 show_Scsi_Cmnd(ptr
, m
);
797 local_irq_restore(flags
);
802 * Function : void NCR5380_init (struct Scsi_Host *instance)
804 * Purpose : initializes *instance and corresponding 5380 chip.
806 * Inputs : instance - instantiation of the 5380 driver.
808 * Notes : I assume that the host, hostno, and id bits have been
809 * set correctly. I don't care about the irq and other fields.
813 static int __init
NCR5380_init(struct Scsi_Host
*instance
, int flags
)
816 SETUP_HOSTDATA(instance
);
820 hostdata
->aborted
= 0;
821 hostdata
->id_mask
= 1 << instance
->this_id
;
822 hostdata
->id_higher_mask
= 0;
823 for (i
= hostdata
->id_mask
; i
<= 0x80; i
<<= 1)
824 if (i
> hostdata
->id_mask
)
825 hostdata
->id_higher_mask
|= i
;
826 for (i
= 0; i
< 8; ++i
)
827 hostdata
->busy
[i
] = 0;
831 #if defined (REAL_DMA)
832 hostdata
->dma_len
= 0;
834 hostdata
->targets_present
= 0;
835 hostdata
->connected
= NULL
;
836 hostdata
->issue_queue
= NULL
;
837 hostdata
->disconnected_queue
= NULL
;
838 hostdata
->flags
= FLAG_CHECK_LAST_BYTE_SENT
;
841 the_template
= instance
->hostt
;
842 first_instance
= instance
;
846 if ((instance
->cmd_per_lun
> 1) || (instance
->can_queue
> 1))
847 printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n"
848 " without AUTOSENSE option, contingent allegiance conditions may\n"
849 " be incorrectly cleared.\n", HOSTNO
);
850 #endif /* def AUTOSENSE */
852 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
853 NCR5380_write(MODE_REG
, MR_BASE
);
854 NCR5380_write(TARGET_COMMAND_REG
, 0);
855 NCR5380_write(SELECT_ENABLE_REG
, 0);
860 static void NCR5380_exit(struct Scsi_Host
*instance
)
862 /* Empty, as we didn't schedule any delayed work */
866 * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd,
867 * void (*done)(Scsi_Cmnd *))
869 * Purpose : enqueues a SCSI command
871 * Inputs : cmd - SCSI command, done - function called on completion, with
872 * a pointer to the command descriptor.
877 * cmd is added to the per instance issue_queue, with minor
878 * twiddling done to the host specific fields of cmd. If the
879 * main coroutine is not running, it is restarted.
883 static int NCR5380_queue_command_lck(Scsi_Cmnd
*cmd
, void (*done
)(Scsi_Cmnd
*))
885 SETUP_HOSTDATA(cmd
->device
->host
);
889 #if (NDEBUG & NDEBUG_NO_WRITE)
890 switch (cmd
->cmnd
[0]) {
893 printk(KERN_NOTICE
"scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
895 cmd
->result
= (DID_ERROR
<< 16);
899 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
903 if (!hostdata
->connected
&& !hostdata
->issue_queue
&&
904 !hostdata
->disconnected_queue
) {
905 hostdata
->timebase
= jiffies
;
908 # ifdef NCR5380_STAT_LIMIT
909 if (scsi_bufflen(cmd
) > NCR5380_STAT_LIMIT
)
911 switch (cmd
->cmnd
[0]) {
915 hostdata
->time_write
[cmd
->device
->id
] -= (jiffies
- hostdata
->timebase
);
916 hostdata
->bytes_write
[cmd
->device
->id
] += scsi_bufflen(cmd
);
917 hostdata
->pendingw
++;
922 hostdata
->time_read
[cmd
->device
->id
] -= (jiffies
- hostdata
->timebase
);
923 hostdata
->bytes_read
[cmd
->device
->id
] += scsi_bufflen(cmd
);
924 hostdata
->pendingr
++;
930 * We use the host_scribble field as a pointer to the next command
935 cmd
->scsi_done
= done
;
940 * Insert the cmd into the issue queue. Note that REQUEST SENSE
941 * commands are added to the head of the queue since any command will
942 * clear the contingent allegiance condition that exists and the
943 * sense data is only guaranteed to be valid while the condition exists.
946 local_irq_save(flags
);
947 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
948 * Otherwise a running NCR5380_main may steal the lock.
949 * Lock before actually inserting due to fairness reasons explained in
950 * atari_scsi.c. If we insert first, then it's impossible for this driver
951 * to release the lock.
952 * Stop timer for this command while waiting for the lock, or timeouts
953 * may happen (and they really do), and it's no good if the command doesn't
954 * appear in any of the queues.
955 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
956 * because also a timer int can trigger an abort or reset, which would
957 * alter queues and touch the lock.
960 /* perhaps stop command timer here */
962 /* perhaps restart command timer here */
964 if (!(hostdata
->issue_queue
) || (cmd
->cmnd
[0] == REQUEST_SENSE
)) {
965 LIST(cmd
, hostdata
->issue_queue
);
966 SET_NEXT(cmd
, hostdata
->issue_queue
);
967 hostdata
->issue_queue
= cmd
;
969 for (tmp
= (Scsi_Cmnd
*)hostdata
->issue_queue
;
970 NEXT(tmp
); tmp
= NEXT(tmp
))
975 local_irq_restore(flags
);
977 dprintk(NDEBUG_QUEUES
, "scsi%d: command added to %s of queue\n", H_NO(cmd
),
978 (cmd
->cmnd
[0] == REQUEST_SENSE
) ? "head" : "tail");
980 /* If queue_command() is called from an interrupt (real one or bottom
981 * half), we let queue_main() do the job of taking care about main. If it
982 * is already running, this is a no-op, else main will be queued.
984 * If we're not in an interrupt, we can call NCR5380_main()
985 * unconditionally, because it cannot be already running.
987 if (in_interrupt() || ((flags
>> 8) & 7) >= 6)
994 static DEF_SCSI_QCMD(NCR5380_queue_command
)
997 * Function : NCR5380_main (void)
999 * Purpose : NCR5380_main is a coroutine that runs as long as more work can
1000 * be done on the NCR5380 host adapters in a system. Both
1001 * NCR5380_queue_command() and NCR5380_intr() will try to start it
1002 * in case it is not running.
1004 * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
1005 * reenable them. This prevents reentrancy and kernel stack overflow.
1008 static void NCR5380_main(struct work_struct
*work
)
1010 Scsi_Cmnd
*tmp
, *prev
;
1011 struct Scsi_Host
*instance
= first_instance
;
1012 struct NCR5380_hostdata
*hostdata
= HOSTDATA(instance
);
1014 unsigned long flags
;
1017 * We run (with interrupts disabled) until we're sure that none of
1018 * the host adapters have anything that can be done, at which point
1019 * we set main_running to 0 and exit.
1021 * Interrupts are enabled before doing various other internal
1022 * instructions, after we've decided that we need to run through
1025 * this should prevent any race conditions.
1027 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1028 * because also a timer int can trigger an abort or reset, which can
1029 * alter queues and touch the Falcon lock.
1032 /* Tell int handlers main() is now already executing. Note that
1033 no races are possible here. If an int comes in before
1034 'main_running' is set here, and queues/executes main via the
1035 task queue, it doesn't do any harm, just this instance of main
1036 won't find any work left to do. */
1041 local_save_flags(flags
);
1043 local_irq_disable(); /* Freeze request queues */
1046 if (!hostdata
->connected
) {
1047 dprintk(NDEBUG_MAIN
, "scsi%d: not connected\n", HOSTNO
);
1049 * Search through the issue_queue for a command destined
1050 * for a target that's not busy.
1052 #if (NDEBUG & NDEBUG_LISTS)
1053 for (tmp
= (Scsi_Cmnd
*) hostdata
->issue_queue
, prev
= NULL
;
1054 tmp
&& (tmp
!= prev
); prev
= tmp
, tmp
= NEXT(tmp
))
1056 /*printk("%p ", tmp);*/
1057 if ((tmp
== prev
) && tmp
)
1059 /* else printk("\n"); */
1061 for (tmp
= (Scsi_Cmnd
*) hostdata
->issue_queue
,
1062 prev
= NULL
; tmp
; prev
= tmp
, tmp
= NEXT(tmp
)) {
1064 #if (NDEBUG & NDEBUG_LISTS)
1066 printk("MAIN tmp=%p target=%d busy=%d lun=%d\n",
1067 tmp
, tmp
->device
->id
, hostdata
->busy
[tmp
->device
->id
],
1070 /* When we find one, remove it from the issue queue. */
1071 /* ++guenther: possible race with Falcon locking */
1074 !is_lun_busy( tmp
, tmp
->cmnd
[0] != REQUEST_SENSE
)
1076 !(hostdata
->busy
[tmp
->device
->id
] & (1 << tmp
->device
->lun
))
1079 /* ++guenther: just to be sure, this must be atomic */
1080 local_irq_disable();
1082 REMOVE(prev
, NEXT(prev
), tmp
, NEXT(tmp
));
1083 SET_NEXT(prev
, NEXT(tmp
));
1085 REMOVE(-1, hostdata
->issue_queue
, tmp
, NEXT(tmp
));
1086 hostdata
->issue_queue
= NEXT(tmp
);
1088 SET_NEXT(tmp
, NULL
);
1089 falcon_dont_release
++;
1091 /* reenable interrupts after finding one */
1092 local_irq_restore(flags
);
1095 * Attempt to establish an I_T_L nexus here.
1096 * On success, instance->hostdata->connected is set.
1097 * On failure, we must add the command back to the
1098 * issue queue so we can keep trying.
1100 dprintk(NDEBUG_MAIN
, "scsi%d: main(): command for target %d "
1101 "lun %d removed from issue_queue\n",
1102 HOSTNO
, tmp
->device
->id
, tmp
->device
->lun
);
1104 * REQUEST SENSE commands are issued without tagged
1105 * queueing, even on SCSI-II devices because the
1106 * contingent allegiance condition exists for the
1109 /* ++roman: ...and the standard also requires that
1110 * REQUEST SENSE command are untagged.
1114 cmd_get_tag(tmp
, tmp
->cmnd
[0] != REQUEST_SENSE
);
1116 if (!NCR5380_select(instance
, tmp
,
1117 (tmp
->cmnd
[0] == REQUEST_SENSE
) ? TAG_NONE
:
1119 falcon_dont_release
--;
1120 /* release if target did not response! */
1121 falcon_release_lock_if_possible(hostdata
);
1124 local_irq_disable();
1125 LIST(tmp
, hostdata
->issue_queue
);
1126 SET_NEXT(tmp
, hostdata
->issue_queue
);
1127 hostdata
->issue_queue
= tmp
;
1131 falcon_dont_release
--;
1132 local_irq_restore(flags
);
1133 dprintk(NDEBUG_MAIN
, "scsi%d: main(): select() failed, "
1134 "returned to issue_queue\n", HOSTNO
);
1135 if (hostdata
->connected
)
1138 } /* if target/lun/target queue is not busy */
1139 } /* for issue_queue */
1140 } /* if (!hostdata->connected) */
1142 if (hostdata
->connected
1144 && !hostdata
->dma_len
1147 local_irq_restore(flags
);
1148 dprintk(NDEBUG_MAIN
, "scsi%d: main: performing information transfer\n",
1150 NCR5380_information_transfer(instance
);
1151 dprintk(NDEBUG_MAIN
, "scsi%d: main: done set false\n", HOSTNO
);
1156 /* Better allow ints _after_ 'main_running' has been cleared, else
1157 an interrupt could believe we'll pick up the work it left for
1158 us, but we won't see it anymore here... */
1160 local_irq_restore(flags
);
1166 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1168 * Purpose : Called by interrupt handler when DMA finishes or a phase
1169 * mismatch occurs (which would finish the DMA transfer).
1171 * Inputs : instance - this instance of the NCR5380.
1175 static void NCR5380_dma_complete(struct Scsi_Host
*instance
)
1177 SETUP_HOSTDATA(instance
);
1178 int transfered
, saved_data
= 0, overrun
= 0, cnt
, toPIO
;
1179 unsigned char **data
, p
;
1180 volatile int *count
;
1182 if (!hostdata
->connected
) {
1183 printk(KERN_WARNING
"scsi%d: received end of DMA interrupt with "
1184 "no connected cmd\n", HOSTNO
);
1188 if (atari_read_overruns
) {
1189 p
= hostdata
->connected
->SCp
.phase
;
1192 if ((NCR5380_read(BUS_AND_STATUS_REG
) &
1193 (BASR_PHASE_MATCH
|BASR_ACK
)) ==
1194 (BASR_PHASE_MATCH
|BASR_ACK
)) {
1195 saved_data
= NCR5380_read(INPUT_DATA_REG
);
1197 dprintk(NDEBUG_DMA
, "scsi%d: read overrun handled\n", HOSTNO
);
1202 dprintk(NDEBUG_DMA
, "scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1203 HOSTNO
, NCR5380_read(BUS_AND_STATUS_REG
),
1204 NCR5380_read(STATUS_REG
));
1206 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1207 NCR5380_write(MODE_REG
, MR_BASE
);
1208 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1210 transfered
= hostdata
->dma_len
- NCR5380_dma_residual(instance
);
1211 hostdata
->dma_len
= 0;
1213 data
= (unsigned char **)&hostdata
->connected
->SCp
.ptr
;
1214 count
= &hostdata
->connected
->SCp
.this_residual
;
1215 *data
+= transfered
;
1216 *count
-= transfered
;
1218 if (atari_read_overruns
) {
1219 if ((NCR5380_read(STATUS_REG
) & PHASE_MASK
) == p
&& (p
& SR_IO
)) {
1220 cnt
= toPIO
= atari_read_overruns
;
1222 dprintk(NDEBUG_DMA
, "Got an input overrun, using saved byte\n");
1223 *(*data
)++ = saved_data
;
1228 dprintk(NDEBUG_DMA
, "Doing %d-byte PIO to 0x%08lx\n", cnt
, (long)*data
);
1229 NCR5380_transfer_pio(instance
, &p
, &cnt
, data
);
1230 *count
-= toPIO
- cnt
;
1234 #endif /* REAL_DMA */
1238 * Function : void NCR5380_intr (int irq)
1240 * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1241 * from the disconnected queue, and restarting NCR5380_main()
1244 * Inputs : int irq, irq that caused this interrupt.
1248 static irqreturn_t
NCR5380_intr(int irq
, void *dev_id
)
1250 struct Scsi_Host
*instance
= first_instance
;
1251 int done
= 1, handled
= 0;
1254 dprintk(NDEBUG_INTR
, "scsi%d: NCR5380 irq triggered\n", HOSTNO
);
1256 /* Look for pending interrupts */
1257 basr
= NCR5380_read(BUS_AND_STATUS_REG
);
1258 dprintk(NDEBUG_INTR
, "scsi%d: BASR=%02x\n", HOSTNO
, basr
);
1259 /* dispatch to appropriate routine if found and done=0 */
1260 if (basr
& BASR_IRQ
) {
1261 NCR5380_dprint(NDEBUG_INTR
, instance
);
1262 if ((NCR5380_read(STATUS_REG
) & (SR_SEL
|SR_IO
)) == (SR_SEL
|SR_IO
)) {
1265 dprintk(NDEBUG_INTR
, "scsi%d: SEL interrupt\n", HOSTNO
);
1266 NCR5380_reselect(instance
);
1267 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1268 } else if (basr
& BASR_PARITY_ERROR
) {
1269 dprintk(NDEBUG_INTR
, "scsi%d: PARITY interrupt\n", HOSTNO
);
1270 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1271 } else if ((NCR5380_read(STATUS_REG
) & SR_RST
) == SR_RST
) {
1272 dprintk(NDEBUG_INTR
, "scsi%d: RESET interrupt\n", HOSTNO
);
1273 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1276 * The rest of the interrupt conditions can occur only during a
1280 #if defined(REAL_DMA)
1282 * We should only get PHASE MISMATCH and EOP interrupts if we have
1283 * DMA enabled, so do a sanity check based on the current setting
1284 * of the MODE register.
1287 if ((NCR5380_read(MODE_REG
) & MR_DMA_MODE
) &&
1288 ((basr
& BASR_END_DMA_TRANSFER
) ||
1289 !(basr
& BASR_PHASE_MATCH
))) {
1291 dprintk(NDEBUG_INTR
, "scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO
);
1292 NCR5380_dma_complete( instance
);
1296 #endif /* REAL_DMA */
1298 /* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1299 if (basr
& BASR_PHASE_MATCH
)
1300 printk(KERN_NOTICE
"scsi%d: unknown interrupt, "
1301 "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1302 HOSTNO
, basr
, NCR5380_read(MODE_REG
),
1303 NCR5380_read(STATUS_REG
));
1304 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1306 } /* if !(SELECTION || PARITY) */
1308 } /* BASR & IRQ */ else {
1309 printk(KERN_NOTICE
"scsi%d: interrupt without IRQ bit set in BASR, "
1310 "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO
, basr
,
1311 NCR5380_read(MODE_REG
), NCR5380_read(STATUS_REG
));
1312 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
1316 dprintk(NDEBUG_INTR
, "scsi%d: in int routine, calling main\n", HOSTNO
);
1317 /* Put a call to NCR5380_main() on the queue... */
1320 return IRQ_RETVAL(handled
);
1323 #ifdef NCR5380_STATS
1324 static void collect_stats(struct NCR5380_hostdata
* hostdata
, Scsi_Cmnd
*cmd
)
1326 # ifdef NCR5380_STAT_LIMIT
1327 if (scsi_bufflen(cmd
) > NCR5380_STAT_LIMIT
)
1329 switch (cmd
->cmnd
[0]) {
1333 hostdata
->time_write
[cmd
->device
->id
] += (jiffies
- hostdata
->timebase
);
1334 /*hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);*/
1335 hostdata
->pendingw
--;
1340 hostdata
->time_read
[cmd
->device
->id
] += (jiffies
- hostdata
->timebase
);
1341 /*hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);*/
1342 hostdata
->pendingr
--;
1349 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1352 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1353 * including ARBITRATION, SELECTION, and initial message out for
1354 * IDENTIFY and queue messages.
1356 * Inputs : instance - instantiation of the 5380 driver on which this
1357 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1358 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1359 * the command that is presently connected.
1361 * Returns : -1 if selection could not execute for some reason,
1362 * 0 if selection succeeded or failed because the target
1366 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1367 * with registers as they should have been on entry - ie
1368 * SELECT_ENABLE will be set appropriately, the NCR5380
1369 * will cease to drive any SCSI bus signals.
1371 * If successful : I_T_L or I_T_L_Q nexus will be established,
1372 * instance->connected will be set to cmd.
1373 * SELECT interrupt will be disabled.
1375 * If failed (no target) : cmd->scsi_done() will be called, and the
1376 * cmd->result host byte set to DID_BAD_TARGET.
1379 static int NCR5380_select(struct Scsi_Host
*instance
, Scsi_Cmnd
*cmd
, int tag
)
1381 SETUP_HOSTDATA(instance
);
1382 unsigned char tmp
[3], phase
;
1383 unsigned char *data
;
1385 unsigned long timeout
;
1386 unsigned long flags
;
1388 hostdata
->restart_select
= 0;
1389 NCR5380_dprint(NDEBUG_ARBITRATION
, instance
);
1390 dprintk(NDEBUG_ARBITRATION
, "scsi%d: starting arbitration, id = %d\n", HOSTNO
,
1394 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1395 * data bus during SELECTION.
1398 local_irq_save(flags
);
1399 if (hostdata
->connected
) {
1400 local_irq_restore(flags
);
1403 NCR5380_write(TARGET_COMMAND_REG
, 0);
1406 * Start arbitration.
1409 NCR5380_write(OUTPUT_DATA_REG
, hostdata
->id_mask
);
1410 NCR5380_write(MODE_REG
, MR_ARBITRATE
);
1412 local_irq_restore(flags
);
1414 /* Wait for arbitration logic to complete */
1415 #if defined(NCR_TIMEOUT)
1417 unsigned long timeout
= jiffies
+ 2*NCR_TIMEOUT
;
1419 while (!(NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_PROGRESS
) &&
1420 time_before(jiffies
, timeout
) && !hostdata
->connected
)
1422 if (time_after_eq(jiffies
, timeout
)) {
1423 printk("scsi : arbitration timeout at %d\n", __LINE__
);
1424 NCR5380_write(MODE_REG
, MR_BASE
);
1425 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1429 #else /* NCR_TIMEOUT */
1430 while (!(NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_PROGRESS
) &&
1431 !hostdata
->connected
)
1435 dprintk(NDEBUG_ARBITRATION
, "scsi%d: arbitration complete\n", HOSTNO
);
1437 if (hostdata
->connected
) {
1438 NCR5380_write(MODE_REG
, MR_BASE
);
1442 * The arbitration delay is 2.2us, but this is a minimum and there is
1443 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1444 * the integral nature of udelay().
1450 /* Check for lost arbitration */
1451 if ((NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_LOST
) ||
1452 (NCR5380_read(CURRENT_SCSI_DATA_REG
) & hostdata
->id_higher_mask
) ||
1453 (NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_LOST
) ||
1454 hostdata
->connected
) {
1455 NCR5380_write(MODE_REG
, MR_BASE
);
1456 dprintk(NDEBUG_ARBITRATION
, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1461 /* after/during arbitration, BSY should be asserted.
1462 IBM DPES-31080 Version S31Q works now */
1463 /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
1464 NCR5380_write(INITIATOR_COMMAND_REG
,
1465 ICR_BASE
| ICR_ASSERT_SEL
| ICR_ASSERT_BSY
);
1467 if ((NCR5380_read(INITIATOR_COMMAND_REG
) & ICR_ARBITRATION_LOST
) ||
1468 hostdata
->connected
) {
1469 NCR5380_write(MODE_REG
, MR_BASE
);
1470 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1471 dprintk(NDEBUG_ARBITRATION
, "scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1477 * Again, bus clear + bus settle time is 1.2us, however, this is
1478 * a minimum so we'll udelay ceil(1.2)
1481 #ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1482 /* ++roman: But some targets (see above :-) seem to need a bit more... */
1488 if (hostdata
->connected
) {
1489 NCR5380_write(MODE_REG
, MR_BASE
);
1490 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1494 dprintk(NDEBUG_ARBITRATION
, "scsi%d: won arbitration\n", HOSTNO
);
1497 * Now that we have won arbitration, start Selection process, asserting
1498 * the host and target ID's on the SCSI bus.
1501 NCR5380_write(OUTPUT_DATA_REG
, (hostdata
->id_mask
| (1 << cmd
->device
->id
)));
1504 * Raise ATN while SEL is true before BSY goes false from arbitration,
1505 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1506 * phase immediately after selection.
1509 NCR5380_write(INITIATOR_COMMAND_REG
, (ICR_BASE
| ICR_ASSERT_BSY
|
1510 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
| ICR_ASSERT_SEL
));
1511 NCR5380_write(MODE_REG
, MR_BASE
);
1514 * Reselect interrupts must be turned off prior to the dropping of BSY,
1515 * otherwise we will trigger an interrupt.
1518 if (hostdata
->connected
) {
1519 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1523 NCR5380_write(SELECT_ENABLE_REG
, 0);
1526 * The initiator shall then wait at least two deskew delays and release
1529 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1532 NCR5380_write(INITIATOR_COMMAND_REG
, (ICR_BASE
| ICR_ASSERT_DATA
|
1533 ICR_ASSERT_ATN
| ICR_ASSERT_SEL
));
1536 * Something weird happens when we cease to drive BSY - looks
1537 * like the board/chip is letting us do another read before the
1538 * appropriate propagation delay has expired, and we're confusing
1539 * a BSY signal from ourselves as the target's response to SELECTION.
1541 * A small delay (the 'C++' frontend breaks the pipeline with an
1542 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1543 * tighter 'C' code breaks and requires this) solves the problem -
1544 * the 1 us delay is arbitrary, and only used because this delay will
1545 * be the same on other platforms and since it works here, it should
1548 * wingel suggests that this could be due to failing to wait
1554 dprintk(NDEBUG_SELECTION
, "scsi%d: selecting target %d\n", HOSTNO
, cmd
->device
->id
);
1557 * The SCSI specification calls for a 250 ms timeout for the actual
1561 timeout
= jiffies
+ 25;
1564 * XXX very interesting - we're seeing a bounce where the BSY we
1565 * asserted is being reflected / still asserted (propagation delay?)
1566 * and it's detecting as true. Sigh.
1570 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1571 * IO while SEL is true. But again, there are some disks out the in the
1572 * world that do that nevertheless. (Somebody claimed that this announces
1573 * reselection capability of the target.) So we better skip that test and
1574 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-)
1577 while (time_before(jiffies
, timeout
) &&
1578 !(NCR5380_read(STATUS_REG
) & (SR_BSY
| SR_IO
)))
1581 if ((NCR5380_read(STATUS_REG
) & (SR_SEL
| SR_IO
)) == (SR_SEL
| SR_IO
)) {
1582 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1583 NCR5380_reselect(instance
);
1584 printk(KERN_ERR
"scsi%d: reselection after won arbitration?\n",
1586 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1590 while (time_before(jiffies
, timeout
) && !(NCR5380_read(STATUS_REG
) & SR_BSY
))
1595 * No less than two deskew delays after the initiator detects the
1596 * BSY signal is true, it shall release the SEL signal and may
1597 * change the DATA BUS. -wingel
1602 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1604 if (!(NCR5380_read(STATUS_REG
) & SR_BSY
)) {
1605 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1606 if (hostdata
->targets_present
& (1 << cmd
->device
->id
)) {
1607 printk(KERN_ERR
"scsi%d: weirdness\n", HOSTNO
);
1608 if (hostdata
->restart_select
)
1609 printk(KERN_NOTICE
"\trestart select\n");
1610 NCR5380_dprint(NDEBUG_ANY
, instance
);
1611 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1614 cmd
->result
= DID_BAD_TARGET
<< 16;
1615 #ifdef NCR5380_STATS
1616 collect_stats(hostdata
, cmd
);
1621 cmd
->scsi_done(cmd
);
1622 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1623 dprintk(NDEBUG_SELECTION
, "scsi%d: target did not respond within 250ms\n", HOSTNO
);
1624 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
1628 hostdata
->targets_present
|= (1 << cmd
->device
->id
);
1631 * Since we followed the SCSI spec, and raised ATN while SEL
1632 * was true but before BSY was false during selection, the information
1633 * transfer phase should be a MESSAGE OUT phase so that we can send the
1636 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1637 * message (2 bytes) with a tag ID that we increment with every command
1638 * until it wraps back to 0.
1640 * XXX - it turns out that there are some broken SCSI-II devices,
1641 * which claim to support tagged queuing but fail when more than
1642 * some number of commands are issued at once.
1645 /* Wait for start of REQ/ACK handshake */
1646 while (!(NCR5380_read(STATUS_REG
) & SR_REQ
))
1649 dprintk(NDEBUG_SELECTION
, "scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1650 HOSTNO
, cmd
->device
->id
);
1651 tmp
[0] = IDENTIFY(1, cmd
->device
->lun
);
1654 if (cmd
->tag
!= TAG_NONE
) {
1655 tmp
[1] = hostdata
->last_message
= SIMPLE_QUEUE_TAG
;
1663 #endif /* SUPPORT_TAGS */
1665 /* Send message(s) */
1667 phase
= PHASE_MSGOUT
;
1668 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
1669 dprintk(NDEBUG_SELECTION
, "scsi%d: nexus established.\n", HOSTNO
);
1670 /* XXX need to handle errors here */
1671 hostdata
->connected
= cmd
;
1672 #ifndef SUPPORT_TAGS
1673 hostdata
->busy
[cmd
->device
->id
] |= (1 << cmd
->device
->lun
);
1676 initialize_SCp(cmd
);
1682 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1683 * unsigned char *phase, int *count, unsigned char **data)
1685 * Purpose : transfers data in given phase using polled I/O
1687 * Inputs : instance - instance of driver, *phase - pointer to
1688 * what phase is expected, *count - pointer to number of
1689 * bytes to transfer, **data - pointer to data pointer.
1691 * Returns : -1 when different phase is entered without transferring
1692 * maximum number of bytes, 0 if all bytes are transferred or exit
1695 * Also, *phase, *count, *data are modified in place.
1697 * XXX Note : handling for bus free may be useful.
1701 * Note : this code is not as quick as it could be, however it
1702 * IS 100% reliable, and for the actual data transfer where speed
1703 * counts, we will always do a pseudo DMA or DMA transfer.
1706 static int NCR5380_transfer_pio(struct Scsi_Host
*instance
,
1707 unsigned char *phase
, int *count
,
1708 unsigned char **data
)
1710 register unsigned char p
= *phase
, tmp
;
1711 register int c
= *count
;
1712 register unsigned char *d
= *data
;
1715 * The NCR5380 chip will only drive the SCSI bus when the
1716 * phase specified in the appropriate bits of the TARGET COMMAND
1717 * REGISTER match the STATUS REGISTER
1720 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1724 * Wait for assertion of REQ, after which the phase bits will be
1727 while (!((tmp
= NCR5380_read(STATUS_REG
)) & SR_REQ
))
1730 dprintk(NDEBUG_HANDSHAKE
, "scsi%d: REQ detected\n", HOSTNO
);
1732 /* Check for phase mismatch */
1733 if ((tmp
& PHASE_MASK
) != p
) {
1734 dprintk(NDEBUG_PIO
, "scsi%d: phase mismatch\n", HOSTNO
);
1735 NCR5380_dprint_phase(NDEBUG_PIO
, instance
);
1739 /* Do actual transfer from SCSI bus to / from memory */
1741 NCR5380_write(OUTPUT_DATA_REG
, *d
);
1743 *d
= NCR5380_read(CURRENT_SCSI_DATA_REG
);
1748 * The SCSI standard suggests that in MSGOUT phase, the initiator
1749 * should drop ATN on the last byte of the message phase
1750 * after REQ has been asserted for the handshake but before
1751 * the initiator raises ACK.
1755 if (!((p
& SR_MSG
) && c
> 1)) {
1756 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
);
1757 NCR5380_dprint(NDEBUG_PIO
, instance
);
1758 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1759 ICR_ASSERT_DATA
| ICR_ASSERT_ACK
);
1761 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1762 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
);
1763 NCR5380_dprint(NDEBUG_PIO
, instance
);
1764 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
1765 ICR_ASSERT_DATA
| ICR_ASSERT_ATN
| ICR_ASSERT_ACK
);
1768 NCR5380_dprint(NDEBUG_PIO
, instance
);
1769 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ACK
);
1772 while (NCR5380_read(STATUS_REG
) & SR_REQ
)
1775 dprintk(NDEBUG_HANDSHAKE
, "scsi%d: req false, handshake complete\n", HOSTNO
);
1778 * We have several special cases to consider during REQ/ACK handshaking :
1779 * 1. We were in MSGOUT phase, and we are on the last byte of the
1780 * message. ATN must be dropped as ACK is dropped.
1782 * 2. We are in a MSGIN phase, and we are on the last byte of the
1783 * message. We must exit with ACK asserted, so that the calling
1784 * code may raise ATN before dropping ACK to reject the message.
1786 * 3. ACK and ATN are clear and the target may proceed as normal.
1788 if (!(p
== PHASE_MSGIN
&& c
== 1)) {
1789 if (p
== PHASE_MSGOUT
&& c
> 1)
1790 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1792 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
1796 dprintk(NDEBUG_PIO
, "scsi%d: residual %d\n", HOSTNO
, c
);
1800 tmp
= NCR5380_read(STATUS_REG
);
1801 /* The phase read from the bus is valid if either REQ is (already)
1802 * asserted or if ACK hasn't been released yet. The latter is the case if
1803 * we're in MSGIN and all wanted bytes have been received.
1805 if ((tmp
& SR_REQ
) || (p
== PHASE_MSGIN
&& c
== 0))
1806 *phase
= tmp
& PHASE_MASK
;
1808 *phase
= PHASE_UNKNOWN
;
1810 if (!c
|| (*phase
== p
))
1817 * Function : do_abort (Scsi_Host *host)
1819 * Purpose : abort the currently established nexus. Should only be
1820 * called from a routine which can drop into a
1822 * Returns : 0 on success, -1 on failure.
1825 static int do_abort(struct Scsi_Host
*host
)
1827 unsigned char tmp
, *msgptr
, phase
;
1830 /* Request message out phase */
1831 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1834 * Wait for the target to indicate a valid phase by asserting
1835 * REQ. Once this happens, we'll have either a MSGOUT phase
1836 * and can immediately send the ABORT message, or we'll have some
1837 * other phase and will have to source/sink data.
1839 * We really don't care what value was on the bus or what value
1840 * the target sees, so we just handshake.
1843 while (!((tmp
= NCR5380_read(STATUS_REG
)) & SR_REQ
))
1846 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(tmp
));
1848 if ((tmp
& PHASE_MASK
) != PHASE_MSGOUT
) {
1849 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
|
1851 while (NCR5380_read(STATUS_REG
) & SR_REQ
)
1853 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
1859 phase
= PHASE_MSGOUT
;
1860 NCR5380_transfer_pio(host
, &phase
, &len
, &msgptr
);
1863 * If we got here, and the command completed successfully,
1864 * we're about to go into bus free state.
1867 return len
? -1 : 0;
1870 #if defined(REAL_DMA)
1872 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1873 * unsigned char *phase, int *count, unsigned char **data)
1875 * Purpose : transfers data in given phase using either real
1878 * Inputs : instance - instance of driver, *phase - pointer to
1879 * what phase is expected, *count - pointer to number of
1880 * bytes to transfer, **data - pointer to data pointer.
1882 * Returns : -1 when different phase is entered without transferring
1883 * maximum number of bytes, 0 if all bytes or transferred or exit
1886 * Also, *phase, *count, *data are modified in place.
1891 static int NCR5380_transfer_dma(struct Scsi_Host
*instance
,
1892 unsigned char *phase
, int *count
,
1893 unsigned char **data
)
1895 SETUP_HOSTDATA(instance
);
1896 register int c
= *count
;
1897 register unsigned char p
= *phase
;
1898 register unsigned char *d
= *data
;
1900 unsigned long flags
;
1902 if ((tmp
= (NCR5380_read(STATUS_REG
) & PHASE_MASK
)) != p
) {
1907 if (atari_read_overruns
&& (p
& SR_IO
))
1908 c
-= atari_read_overruns
;
1910 dprintk(NDEBUG_DMA
, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1911 HOSTNO
, (p
& SR_IO
) ? "reading" : "writing",
1912 c
, (p
& SR_IO
) ? "to" : "from", d
);
1914 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(p
));
1917 NCR5380_write(MODE_REG
, MR_BASE
| MR_DMA_MODE
| MR_ENABLE_EOP_INTR
| MR_MONITOR_BSY
);
1918 #endif /* def REAL_DMA */
1921 /* On the Medusa, it is a must to initialize the DMA before
1922 * starting the NCR. This is also the cleaner way for the TT.
1924 local_irq_save(flags
);
1925 hostdata
->dma_len
= (p
& SR_IO
) ?
1926 NCR5380_dma_read_setup(instance
, d
, c
) :
1927 NCR5380_dma_write_setup(instance
, d
, c
);
1928 local_irq_restore(flags
);
1932 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG
, 0);
1934 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_DATA
);
1935 NCR5380_write(START_DMA_SEND_REG
, 0);
1939 /* On the Falcon, the DMA setup must be done after the last */
1940 /* NCR access, else the DMA setup gets trashed!
1942 local_irq_save(flags
);
1943 hostdata
->dma_len
= (p
& SR_IO
) ?
1944 NCR5380_dma_read_setup(instance
, d
, c
) :
1945 NCR5380_dma_write_setup(instance
, d
, c
);
1946 local_irq_restore(flags
);
1950 #endif /* defined(REAL_DMA) */
1953 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1955 * Purpose : run through the various SCSI phases and do as the target
1956 * directs us to. Operates on the currently connected command,
1957 * instance->connected.
1959 * Inputs : instance, instance for which we are doing commands
1961 * Side effects : SCSI things happen, the disconnected queue will be
1962 * modified if a command disconnects, *instance->connected will
1965 * XXX Note : we need to watch for bus free or a reset condition here
1966 * to recover from an unexpected bus free condition.
1969 static void NCR5380_information_transfer(struct Scsi_Host
*instance
)
1971 SETUP_HOSTDATA(instance
);
1972 unsigned long flags
;
1973 unsigned char msgout
= NOP
;
1976 #if defined(REAL_DMA)
1979 unsigned char *data
;
1980 unsigned char phase
, tmp
, extended_msg
[10], old_phase
= 0xff;
1981 Scsi_Cmnd
*cmd
= (Scsi_Cmnd
*) hostdata
->connected
;
1984 tmp
= NCR5380_read(STATUS_REG
);
1985 /* We only have a valid SCSI phase when REQ is asserted */
1987 phase
= (tmp
& PHASE_MASK
);
1988 if (phase
!= old_phase
) {
1990 NCR5380_dprint_phase(NDEBUG_INFORMATION
, instance
);
1993 if (sink
&& (phase
!= PHASE_MSGOUT
)) {
1994 NCR5380_write(TARGET_COMMAND_REG
, PHASE_SR_TO_TCR(tmp
));
1996 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
|
1998 while (NCR5380_read(STATUS_REG
) & SR_REQ
)
2000 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
2008 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2009 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2010 "aborted\n", HOSTNO
);
2013 cmd
->result
= DID_ERROR
<< 16;
2014 cmd
->scsi_done(cmd
);
2019 * If there is no room left in the current buffer in the
2020 * scatter-gather list, move onto the next one.
2023 if (!cmd
->SCp
.this_residual
&& cmd
->SCp
.buffers_residual
) {
2025 --cmd
->SCp
.buffers_residual
;
2026 cmd
->SCp
.this_residual
= cmd
->SCp
.buffer
->length
;
2027 cmd
->SCp
.ptr
= sg_virt(cmd
->SCp
.buffer
);
2028 /* ++roman: Try to merge some scatter-buffers if
2029 * they are at contiguous physical addresses.
2031 merge_contiguous_buffers(cmd
);
2032 dprintk(NDEBUG_INFORMATION
, "scsi%d: %d bytes and %d buffers left\n",
2033 HOSTNO
, cmd
->SCp
.this_residual
,
2034 cmd
->SCp
.buffers_residual
);
2038 * The preferred transfer method is going to be
2039 * PSEUDO-DMA for systems that are strictly PIO,
2040 * since we can let the hardware do the handshaking.
2042 * For this to work, we need to know the transfersize
2043 * ahead of time, since the pseudo-DMA code will sit
2044 * in an unconditional loop.
2047 /* ++roman: I suggest, this should be
2049 * instead of leaving REAL_DMA out.
2052 #if defined(REAL_DMA)
2053 if (!cmd
->device
->borken
&&
2054 (transfersize
= NCR5380_dma_xfer_len(instance
,cmd
,phase
)) > 31) {
2056 cmd
->SCp
.phase
= phase
;
2057 if (NCR5380_transfer_dma(instance
, &phase
,
2058 &len
, (unsigned char **)&cmd
->SCp
.ptr
)) {
2060 * If the watchdog timer fires, all future
2061 * accesses to this device will use the
2063 printk(KERN_NOTICE
"scsi%d: switching target %d "
2064 "lun %d to slow handshake\n", HOSTNO
,
2065 cmd
->device
->id
, cmd
->device
->lun
);
2066 cmd
->device
->borken
= 1;
2067 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
|
2071 cmd
->result
= DID_ERROR
<< 16;
2072 cmd
->scsi_done(cmd
);
2073 /* XXX - need to source or sink data here, as appropriate */
2076 /* ++roman: When using real DMA,
2077 * information_transfer() should return after
2078 * starting DMA since it has nothing more to
2083 cmd
->SCp
.this_residual
-= transfersize
- len
;
2087 #endif /* defined(REAL_DMA) */
2088 NCR5380_transfer_pio(instance
, &phase
,
2089 (int *)&cmd
->SCp
.this_residual
,
2090 (unsigned char **)&cmd
->SCp
.ptr
);
2095 NCR5380_write(SELECT_ENABLE_REG
, 0); /* disable reselects */
2096 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2097 cmd
->SCp
.Message
= tmp
;
2101 * Linking lets us reduce the time required to get the
2102 * next command out to the device, hopefully this will
2103 * mean we don't waste another revolution due to the delays
2104 * required by ARBITRATION and another SELECTION.
2106 * In the current implementation proposal, low level drivers
2107 * merely have to start the next command, pointed to by
2108 * next_link, done() is called as with unlinked commands.
2111 case LINKED_CMD_COMPLETE
:
2112 case LINKED_FLG_CMD_COMPLETE
:
2113 /* Accept message by clearing ACK */
2114 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2116 dprintk(NDEBUG_LINKED
, "scsi%d: target %d lun %d linked command "
2117 "complete.\n", HOSTNO
, cmd
->device
->id
, cmd
->device
->lun
);
2119 /* Enable reselect interrupts */
2120 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2122 * Sanity check : A linked command should only terminate
2123 * with one of these messages if there are more linked
2124 * commands available.
2127 if (!cmd
->next_link
) {
2128 printk(KERN_NOTICE
"scsi%d: target %d lun %d "
2129 "linked command complete, no next_link\n",
2130 HOSTNO
, cmd
->device
->id
, cmd
->device
->lun
);
2136 initialize_SCp(cmd
->next_link
);
2137 /* The next command is still part of this process; copy it
2138 * and don't free it! */
2139 cmd
->next_link
->tag
= cmd
->tag
;
2140 cmd
->result
= cmd
->SCp
.Status
| (cmd
->SCp
.Message
<< 8);
2141 dprintk(NDEBUG_LINKED
, "scsi%d: target %d lun %d linked request "
2142 "done, calling scsi_done().\n",
2143 HOSTNO
, cmd
->device
->id
, cmd
->device
->lun
);
2144 #ifdef NCR5380_STATS
2145 collect_stats(hostdata
, cmd
);
2147 cmd
->scsi_done(cmd
);
2148 cmd
= hostdata
->connected
;
2150 #endif /* def LINKED */
2152 case COMMAND_COMPLETE
:
2153 /* Accept message by clearing ACK */
2154 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2155 /* ++guenther: possible race with Falcon locking */
2156 falcon_dont_release
++;
2157 hostdata
->connected
= NULL
;
2158 dprintk(NDEBUG_QUEUES
, "scsi%d: command for target %d, lun %d "
2159 "completed\n", HOSTNO
, cmd
->device
->id
, cmd
->device
->lun
);
2162 if (status_byte(cmd
->SCp
.Status
) == QUEUE_FULL
) {
2163 /* Turn a QUEUE FULL status into BUSY, I think the
2164 * mid level cannot handle QUEUE FULL :-( (The
2165 * command is retried after BUSY). Also update our
2166 * queue size to the number of currently issued
2169 /* ++Andreas: the mid level code knows about
2171 TAG_ALLOC
*ta
= &TagAlloc
[cmd
->device
->id
][cmd
->device
->lun
];
2172 dprintk(NDEBUG_TAGS
, "scsi%d: target %d lun %d returned "
2173 "QUEUE_FULL after %d commands\n",
2174 HOSTNO
, cmd
->device
->id
, cmd
->device
->lun
,
2176 if (ta
->queue_size
> ta
->nr_allocated
)
2177 ta
->nr_allocated
= ta
->queue_size
;
2180 hostdata
->busy
[cmd
->device
->id
] &= ~(1 << cmd
->device
->lun
);
2182 /* Enable reselect interrupts */
2183 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2186 * I'm not sure what the correct thing to do here is :
2188 * If the command that just executed is NOT a request
2189 * sense, the obvious thing to do is to set the result
2190 * code to the values of the stored parameters.
2192 * If it was a REQUEST SENSE command, we need some way to
2193 * differentiate between the failure code of the original
2194 * and the failure code of the REQUEST sense - the obvious
2195 * case is success, where we fall through and leave the
2196 * result code unchanged.
2198 * The non-obvious place is where the REQUEST SENSE failed
2201 if (cmd
->cmnd
[0] != REQUEST_SENSE
)
2202 cmd
->result
= cmd
->SCp
.Status
| (cmd
->SCp
.Message
<< 8);
2203 else if (status_byte(cmd
->SCp
.Status
) != GOOD
)
2204 cmd
->result
= (cmd
->result
& 0x00ffff) | (DID_ERROR
<< 16);
2207 if ((cmd
->cmnd
[0] == REQUEST_SENSE
) &&
2208 hostdata
->ses
.cmd_len
) {
2209 scsi_eh_restore_cmnd(cmd
, &hostdata
->ses
);
2210 hostdata
->ses
.cmd_len
= 0 ;
2213 if ((cmd
->cmnd
[0] != REQUEST_SENSE
) &&
2214 (status_byte(cmd
->SCp
.Status
) == CHECK_CONDITION
)) {
2215 scsi_eh_prep_cmnd(cmd
, &hostdata
->ses
, NULL
, 0, ~0);
2217 dprintk(NDEBUG_AUTOSENSE
, "scsi%d: performing request sense\n", HOSTNO
);
2219 local_irq_save(flags
);
2220 LIST(cmd
,hostdata
->issue_queue
);
2221 SET_NEXT(cmd
, hostdata
->issue_queue
);
2222 hostdata
->issue_queue
= (Scsi_Cmnd
*) cmd
;
2223 local_irq_restore(flags
);
2224 dprintk(NDEBUG_QUEUES
, "scsi%d: REQUEST SENSE added to head of "
2225 "issue queue\n", H_NO(cmd
));
2227 #endif /* def AUTOSENSE */
2229 #ifdef NCR5380_STATS
2230 collect_stats(hostdata
, cmd
);
2232 cmd
->scsi_done(cmd
);
2235 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2237 * Restore phase bits to 0 so an interrupted selection,
2238 * arbitration can resume.
2240 NCR5380_write(TARGET_COMMAND_REG
, 0);
2242 while ((NCR5380_read(STATUS_REG
) & SR_BSY
) && !hostdata
->connected
)
2245 falcon_dont_release
--;
2246 /* ++roman: For Falcon SCSI, release the lock on the
2247 * ST-DMA here if no other commands are waiting on the
2248 * disconnected queue.
2250 falcon_release_lock_if_possible(hostdata
);
2252 case MESSAGE_REJECT
:
2253 /* Accept message by clearing ACK */
2254 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2255 /* Enable reselect interrupts */
2256 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2257 switch (hostdata
->last_message
) {
2258 case HEAD_OF_QUEUE_TAG
:
2259 case ORDERED_QUEUE_TAG
:
2260 case SIMPLE_QUEUE_TAG
:
2261 /* The target obviously doesn't support tagged
2262 * queuing, even though it announced this ability in
2263 * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2264 * clear 'tagged_supported' and lock the LUN, since
2265 * the command is treated as untagged further on.
2267 cmd
->device
->tagged_supported
= 0;
2268 hostdata
->busy
[cmd
->device
->id
] |= (1 << cmd
->device
->lun
);
2269 cmd
->tag
= TAG_NONE
;
2270 dprintk(NDEBUG_TAGS
, "scsi%d: target %d lun %d rejected "
2271 "QUEUE_TAG message; tagged queuing "
2273 HOSTNO
, cmd
->device
->id
, cmd
->device
->lun
);
2278 /* Accept message by clearing ACK */
2279 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2280 local_irq_save(flags
);
2281 cmd
->device
->disconnect
= 1;
2282 LIST(cmd
,hostdata
->disconnected_queue
);
2283 SET_NEXT(cmd
, hostdata
->disconnected_queue
);
2284 hostdata
->connected
= NULL
;
2285 hostdata
->disconnected_queue
= cmd
;
2286 local_irq_restore(flags
);
2287 dprintk(NDEBUG_QUEUES
, "scsi%d: command for target %d lun %d was "
2288 "moved from connected to the "
2289 "disconnected_queue\n", HOSTNO
,
2290 cmd
->device
->id
, cmd
->device
->lun
);
2292 * Restore phase bits to 0 so an interrupted selection,
2293 * arbitration can resume.
2295 NCR5380_write(TARGET_COMMAND_REG
, 0);
2297 /* Enable reselect interrupts */
2298 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2299 /* Wait for bus free to avoid nasty timeouts */
2300 while ((NCR5380_read(STATUS_REG
) & SR_BSY
) && !hostdata
->connected
)
2304 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2305 * operation, in violation of the SCSI spec so we can safely
2306 * ignore SAVE/RESTORE pointers calls.
2308 * Unfortunately, some disks violate the SCSI spec and
2309 * don't issue the required SAVE_POINTERS message before
2310 * disconnecting, and we have to break spec to remain
2314 case RESTORE_POINTERS
:
2315 /* Accept message by clearing ACK */
2316 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2317 /* Enable reselect interrupts */
2318 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2320 case EXTENDED_MESSAGE
:
2322 * Extended messages are sent in the following format :
2324 * 0 EXTENDED_MESSAGE == 1
2325 * 1 length (includes one byte for code, doesn't
2326 * include first two bytes)
2328 * 3..length+1 arguments
2330 * Start the extended message buffer with the EXTENDED_MESSAGE
2331 * byte, since spi_print_msg() wants the whole thing.
2333 extended_msg
[0] = EXTENDED_MESSAGE
;
2334 /* Accept first byte by clearing ACK */
2335 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2337 dprintk(NDEBUG_EXTENDED
, "scsi%d: receiving extended message\n", HOSTNO
);
2340 data
= extended_msg
+ 1;
2341 phase
= PHASE_MSGIN
;
2342 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2343 dprintk(NDEBUG_EXTENDED
, "scsi%d: length=%d, code=0x%02x\n", HOSTNO
,
2344 (int)extended_msg
[1], (int)extended_msg
[2]);
2346 if (!len
&& extended_msg
[1] <=
2347 (sizeof(extended_msg
) - 1)) {
2348 /* Accept third byte by clearing ACK */
2349 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2350 len
= extended_msg
[1] - 1;
2351 data
= extended_msg
+ 3;
2352 phase
= PHASE_MSGIN
;
2354 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2355 dprintk(NDEBUG_EXTENDED
, "scsi%d: message received, residual %d\n",
2358 switch (extended_msg
[2]) {
2361 case EXTENDED_MODIFY_DATA_POINTER
:
2362 case EXTENDED_EXTENDED_IDENTIFY
:
2366 printk(KERN_NOTICE
"scsi%d: error receiving "
2367 "extended message\n", HOSTNO
);
2370 printk(KERN_NOTICE
"scsi%d: extended message "
2371 "code %02x length %d is too long\n",
2372 HOSTNO
, extended_msg
[2], extended_msg
[1]);
2375 /* Fall through to reject message */
2378 * If we get something weird that we aren't expecting,
2383 printk(KERN_DEBUG
"scsi%d: rejecting message ", HOSTNO
);
2384 spi_print_msg(extended_msg
);
2386 } else if (tmp
!= EXTENDED_MESSAGE
)
2387 printk(KERN_DEBUG
"scsi%d: rejecting unknown "
2388 "message %02x from target %d, lun %d\n",
2389 HOSTNO
, tmp
, cmd
->device
->id
, cmd
->device
->lun
);
2391 printk(KERN_DEBUG
"scsi%d: rejecting unknown "
2393 "code %02x, length %d from target %d, lun %d\n",
2394 HOSTNO
, extended_msg
[1], extended_msg
[0],
2395 cmd
->device
->id
, cmd
->device
->lun
);
2398 msgout
= MESSAGE_REJECT
;
2399 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_ATN
);
2401 } /* switch (tmp) */
2406 hostdata
->last_message
= msgout
;
2407 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2408 if (msgout
== ABORT
) {
2412 hostdata
->busy
[cmd
->device
->id
] &= ~(1 << cmd
->device
->lun
);
2414 hostdata
->connected
= NULL
;
2415 cmd
->result
= DID_ERROR
<< 16;
2416 #ifdef NCR5380_STATS
2417 collect_stats(hostdata
, cmd
);
2419 cmd
->scsi_done(cmd
);
2420 NCR5380_write(SELECT_ENABLE_REG
, hostdata
->id_mask
);
2421 falcon_release_lock_if_possible(hostdata
);
2430 * XXX for performance reasons, on machines with a
2431 * PSEUDO-DMA architecture we should probably
2432 * use the dma transfer function.
2434 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2439 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2440 cmd
->SCp
.Status
= tmp
;
2443 printk("scsi%d: unknown phase\n", HOSTNO
);
2444 NCR5380_dprint(NDEBUG_ANY
, instance
);
2445 } /* switch(phase) */
2446 } /* if (tmp * SR_REQ) */
2451 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2453 * Purpose : does reselection, initializing the instance->connected
2454 * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2455 * nexus has been reestablished,
2457 * Inputs : instance - this instance of the NCR5380.
2462 static void NCR5380_reselect(struct Scsi_Host
*instance
)
2464 SETUP_HOSTDATA(instance
);
2465 unsigned char target_mask
;
2466 unsigned char lun
, phase
;
2471 unsigned char msg
[3];
2472 unsigned char *data
;
2473 Scsi_Cmnd
*tmp
= NULL
, *prev
;
2474 /* unsigned long flags; */
2477 * Disable arbitration, etc. since the host adapter obviously
2478 * lost, and tell an interrupted NCR5380_select() to restart.
2481 NCR5380_write(MODE_REG
, MR_BASE
);
2482 hostdata
->restart_select
= 1;
2484 target_mask
= NCR5380_read(CURRENT_SCSI_DATA_REG
) & ~(hostdata
->id_mask
);
2486 dprintk(NDEBUG_RESELECTION
, "scsi%d: reselect\n", HOSTNO
);
2489 * At this point, we have detected that our SCSI ID is on the bus,
2490 * SEL is true and BSY was false for at least one bus settle delay
2493 * We must assert BSY ourselves, until the target drops the SEL
2497 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_BSY
);
2499 while (NCR5380_read(STATUS_REG
) & SR_SEL
)
2501 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2504 * Wait for target to go into MSGIN.
2507 while (!(NCR5380_read(STATUS_REG
) & SR_REQ
))
2512 phase
= PHASE_MSGIN
;
2513 NCR5380_transfer_pio(instance
, &phase
, &len
, &data
);
2515 if (!(msg
[0] & 0x80)) {
2516 printk(KERN_DEBUG
"scsi%d: expecting IDENTIFY message, got ", HOSTNO
);
2521 lun
= (msg
[0] & 0x07);
2524 /* If the phase is still MSGIN, the target wants to send some more
2525 * messages. In case it supports tagged queuing, this is probably a
2526 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2529 if (phase
== PHASE_MSGIN
&& setup_use_tagged_queuing
) {
2530 /* Accept previous IDENTIFY message by clearing ACK */
2531 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2534 if (!NCR5380_transfer_pio(instance
, &phase
, &len
, &data
) &&
2535 msg
[1] == SIMPLE_QUEUE_TAG
)
2537 dprintk(NDEBUG_TAGS
, "scsi%d: target mask %02x, lun %d sent tag %d at "
2538 "reselection\n", HOSTNO
, target_mask
, lun
, tag
);
2543 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2544 * just reestablished, and remove it from the disconnected queue.
2547 for (tmp
= (Scsi_Cmnd
*) hostdata
->disconnected_queue
, prev
= NULL
;
2548 tmp
; prev
= tmp
, tmp
= NEXT(tmp
)) {
2549 if ((target_mask
== (1 << tmp
->device
->id
)) && (lun
== tmp
->device
->lun
)
2551 && (tag
== tmp
->tag
)
2554 /* ++guenther: prevent race with falcon_release_lock */
2555 falcon_dont_release
++;
2557 REMOVE(prev
, NEXT(prev
), tmp
, NEXT(tmp
));
2558 SET_NEXT(prev
, NEXT(tmp
));
2560 REMOVE(-1, hostdata
->disconnected_queue
, tmp
, NEXT(tmp
));
2561 hostdata
->disconnected_queue
= NEXT(tmp
);
2563 SET_NEXT(tmp
, NULL
);
2569 printk(KERN_WARNING
"scsi%d: warning: target bitmask %02x lun %d "
2573 "not in disconnected_queue.\n",
2574 HOSTNO
, target_mask
, lun
2580 * Since we have an established nexus that we can't do anything
2581 * with, we must abort it.
2587 /* Accept message by clearing ACK */
2588 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2590 hostdata
->connected
= tmp
;
2591 dprintk(NDEBUG_RESELECTION
, "scsi%d: nexus established, target = %d, lun = %d, tag = %d\n",
2592 HOSTNO
, tmp
->device
->id
, tmp
->device
->lun
, tmp
->tag
);
2593 falcon_dont_release
--;
2598 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2600 * Purpose : abort a command
2602 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2603 * host byte of the result field to, if zero DID_ABORTED is
2606 * Returns : 0 - success, -1 on failure.
2608 * XXX - there is no way to abort the command that is currently
2609 * connected, you have to wait for it to complete. If this is
2610 * a problem, we could implement longjmp() / setjmp(), setjmp()
2611 * called where the loop started in NCR5380_main().
2615 int NCR5380_abort(Scsi_Cmnd
*cmd
)
2617 struct Scsi_Host
*instance
= cmd
->device
->host
;
2618 SETUP_HOSTDATA(instance
);
2619 Scsi_Cmnd
*tmp
, **prev
;
2620 unsigned long flags
;
2622 printk(KERN_NOTICE
"scsi%d: aborting command\n", HOSTNO
);
2623 scsi_print_command(cmd
);
2625 NCR5380_print_status(instance
);
2627 local_irq_save(flags
);
2629 if (!IS_A_TT() && !falcon_got_lock
)
2630 printk(KERN_ERR
"scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n",
2633 dprintk(NDEBUG_ABORT
, "scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO
,
2634 NCR5380_read(BUS_AND_STATUS_REG
),
2635 NCR5380_read(STATUS_REG
));
2639 * Case 1 : If the command is the currently executing command,
2640 * we'll set the aborted flag and return control so that
2641 * information transfer routine can exit cleanly.
2644 if (hostdata
->connected
== cmd
) {
2646 dprintk(NDEBUG_ABORT
, "scsi%d: aborting connected command\n", HOSTNO
);
2648 * We should perform BSY checking, and make sure we haven't slipped
2652 /* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2654 * Since we can't change phases until we've completed the current
2655 * handshake, we have to source or sink a byte of data if the current
2656 * phase is not MSGOUT.
2660 * Return control to the executing NCR drive so we can clear the
2661 * aborted flag and get back into our main loop.
2664 if (do_abort(instance
) == 0) {
2665 hostdata
->aborted
= 1;
2666 hostdata
->connected
= NULL
;
2667 cmd
->result
= DID_ABORT
<< 16;
2671 hostdata
->busy
[cmd
->device
->id
] &= ~(1 << cmd
->device
->lun
);
2673 local_irq_restore(flags
);
2674 cmd
->scsi_done(cmd
);
2675 falcon_release_lock_if_possible(hostdata
);
2678 /* local_irq_restore(flags); */
2679 printk("scsi%d: abort of connected command failed!\n", HOSTNO
);
2686 * Case 2 : If the command hasn't been issued yet, we simply remove it
2687 * from the issue queue.
2689 for (prev
= (Scsi_Cmnd
**)&(hostdata
->issue_queue
),
2690 tmp
= (Scsi_Cmnd
*)hostdata
->issue_queue
;
2691 tmp
; prev
= NEXTADDR(tmp
), tmp
= NEXT(tmp
)) {
2693 REMOVE(5, *prev
, tmp
, NEXT(tmp
));
2694 (*prev
) = NEXT(tmp
);
2695 SET_NEXT(tmp
, NULL
);
2696 tmp
->result
= DID_ABORT
<< 16;
2697 local_irq_restore(flags
);
2698 dprintk(NDEBUG_ABORT
, "scsi%d: abort removed command from issue queue.\n",
2700 /* Tagged queuing note: no tag to free here, hasn't been assigned
2702 tmp
->scsi_done(tmp
);
2703 falcon_release_lock_if_possible(hostdata
);
2709 * Case 3 : If any commands are connected, we're going to fail the abort
2710 * and let the high level SCSI driver retry at a later time or
2713 * Timeouts, and therefore aborted commands, will be highly unlikely
2714 * and handling them cleanly in this situation would make the common
2715 * case of noresets less efficient, and would pollute our code. So,
2719 if (hostdata
->connected
) {
2720 local_irq_restore(flags
);
2721 dprintk(NDEBUG_ABORT
, "scsi%d: abort failed, command connected.\n", HOSTNO
);
2726 * Case 4: If the command is currently disconnected from the bus, and
2727 * there are no connected commands, we reconnect the I_T_L or
2728 * I_T_L_Q nexus associated with it, go into message out, and send
2731 * This case is especially ugly. In order to reestablish the nexus, we
2732 * need to call NCR5380_select(). The easiest way to implement this
2733 * function was to abort if the bus was busy, and let the interrupt
2734 * handler triggered on the SEL for reselect take care of lost arbitrations
2735 * where necessary, meaning interrupts need to be enabled.
2737 * When interrupts are enabled, the queues may change - so we
2738 * can't remove it from the disconnected queue before selecting it
2739 * because that could cause a failure in hashing the nexus if that
2740 * device reselected.
2742 * Since the queues may change, we can't use the pointers from when we
2745 * So, we must first locate the command, and if NCR5380_select()
2746 * succeeds, then issue the abort, relocate the command and remove
2747 * it from the disconnected queue.
2750 for (tmp
= (Scsi_Cmnd
*) hostdata
->disconnected_queue
; tmp
;
2753 local_irq_restore(flags
);
2754 dprintk(NDEBUG_ABORT
, "scsi%d: aborting disconnected command.\n", HOSTNO
);
2756 if (NCR5380_select(instance
, cmd
, (int)cmd
->tag
))
2759 dprintk(NDEBUG_ABORT
, "scsi%d: nexus reestablished.\n", HOSTNO
);
2763 local_irq_save(flags
);
2764 for (prev
= (Scsi_Cmnd
**)&(hostdata
->disconnected_queue
),
2765 tmp
= (Scsi_Cmnd
*)hostdata
->disconnected_queue
;
2766 tmp
; prev
= NEXTADDR(tmp
), tmp
= NEXT(tmp
)) {
2768 REMOVE(5, *prev
, tmp
, NEXT(tmp
));
2770 SET_NEXT(tmp
, NULL
);
2771 tmp
->result
= DID_ABORT
<< 16;
2772 /* We must unlock the tag/LUN immediately here, since the
2773 * target goes to BUS FREE and doesn't send us another
2774 * message (COMMAND_COMPLETE or the like)
2779 hostdata
->busy
[cmd
->device
->id
] &= ~(1 << cmd
->device
->lun
);
2781 local_irq_restore(flags
);
2782 tmp
->scsi_done(tmp
);
2783 falcon_release_lock_if_possible(hostdata
);
2791 * Case 5 : If we reached this point, the command was not found in any of
2794 * We probably reached this point because of an unlikely race condition
2795 * between the command completing successfully and the abortion code,
2796 * so we won't panic, but we will notify the user in case something really
2800 local_irq_restore(flags
);
2801 printk(KERN_INFO
"scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO
);
2803 /* Maybe it is sufficient just to release the ST-DMA lock... (if
2804 * possible at all) At least, we should check if the lock could be
2805 * released after the abort, in case it is kept due to some bug.
2807 falcon_release_lock_if_possible(hostdata
);
2814 * Function : int NCR5380_reset (Scsi_Cmnd *cmd)
2816 * Purpose : reset the SCSI bus.
2818 * Returns : SUCCESS or FAILURE
2822 static int NCR5380_bus_reset(Scsi_Cmnd
*cmd
)
2824 SETUP_HOSTDATA(cmd
->device
->host
);
2826 unsigned long flags
;
2827 #if defined(RESET_RUN_DONE)
2828 Scsi_Cmnd
*connected
, *disconnected_queue
;
2831 if (!IS_A_TT() && !falcon_got_lock
)
2832 printk(KERN_ERR
"scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n",
2835 NCR5380_print_status(cmd
->device
->host
);
2838 NCR5380_write(TARGET_COMMAND_REG
,
2839 PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG
)));
2841 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
| ICR_ASSERT_RST
);
2843 /* reset NCR registers */
2844 NCR5380_write(INITIATOR_COMMAND_REG
, ICR_BASE
);
2845 NCR5380_write(MODE_REG
, MR_BASE
);
2846 NCR5380_write(TARGET_COMMAND_REG
, 0);
2847 NCR5380_write(SELECT_ENABLE_REG
, 0);
2848 /* ++roman: reset interrupt condition! otherwise no interrupts don't get
2849 * through anymore ... */
2850 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG
);
2852 /* MSch 20140115 - looking at the generic NCR5380 driver, all of this
2854 * Catch-22: if we don't clear all queues, the SCSI driver lock will
2855 * not be reset by atari_scsi_reset()!
2858 #if defined(RESET_RUN_DONE)
2859 /* XXX Should now be done by midlevel code, but it's broken XXX */
2860 /* XXX see below XXX */
2862 /* MSch: old-style reset: actually abort all command processing here */
2864 /* After the reset, there are no more connected or disconnected commands
2865 * and no busy units; to avoid problems with re-inserting the commands
2866 * into the issue_queue (via scsi_done()), the aborted commands are
2867 * remembered in local variables first.
2869 local_irq_save(flags
);
2870 connected
= (Scsi_Cmnd
*)hostdata
->connected
;
2871 hostdata
->connected
= NULL
;
2872 disconnected_queue
= (Scsi_Cmnd
*)hostdata
->disconnected_queue
;
2873 hostdata
->disconnected_queue
= NULL
;
2877 for (i
= 0; i
< 8; ++i
)
2878 hostdata
->busy
[i
] = 0;
2880 hostdata
->dma_len
= 0;
2882 local_irq_restore(flags
);
2884 /* In order to tell the mid-level code which commands were aborted,
2885 * set the command status to DID_RESET and call scsi_done() !!!
2886 * This ultimately aborts processing of these commands in the mid-level.
2889 if ((cmd
= connected
)) {
2890 dprintk(NDEBUG_ABORT
, "scsi%d: reset aborted a connected command\n", H_NO(cmd
));
2891 cmd
->result
= (cmd
->result
& 0xffff) | (DID_RESET
<< 16);
2892 cmd
->scsi_done(cmd
);
2895 for (i
= 0; (cmd
= disconnected_queue
); ++i
) {
2896 disconnected_queue
= NEXT(cmd
);
2897 SET_NEXT(cmd
, NULL
);
2898 cmd
->result
= (cmd
->result
& 0xffff) | (DID_RESET
<< 16);
2899 cmd
->scsi_done(cmd
);
2902 dprintk(NDEBUG_ABORT
, "scsi: reset aborted %d disconnected command(s)\n", i
);
2904 /* The Falcon lock should be released after a reset...
2906 /* ++guenther: moved to atari_scsi_reset(), to prevent a race between
2907 * unlocking and enabling dma interrupt.
2909 /* falcon_release_lock_if_possible( hostdata );*/
2911 /* since all commands have been explicitly terminated, we need to tell
2912 * the midlevel code that the reset was SUCCESSFUL, and there is no
2913 * need to 'wake up' the commands by a request_sense
2918 /* MSch: new-style reset handling: let the mid-level do what it can */
2920 /* ++guenther: MID-LEVEL IS STILL BROKEN.
2921 * Mid-level is supposed to requeue all commands that were active on the
2922 * various low-level queues. In fact it does this, but that's not enough
2923 * because all these commands are subject to timeout. And if a timeout
2924 * happens for any removed command, *_abort() is called but all queues
2925 * are now empty. Abort then gives up the falcon lock, which is fatal,
2926 * since the mid-level will queue more commands and must have the lock
2927 * (it's all happening inside timer interrupt handler!!).
2928 * Even worse, abort will return NOT_RUNNING for all those commands not
2929 * on any queue, so they won't be retried ...
2931 * Conclusion: either scsi.c disables timeout for all resetted commands
2932 * immediately, or we lose! As of linux-2.0.20 it doesn't.
2935 /* After the reset, there are no more connected or disconnected commands
2936 * and no busy units; so clear the low-level status here to avoid
2937 * conflicts when the mid-level code tries to wake up the affected
2941 if (hostdata
->issue_queue
)
2942 dprintk(NDEBUG_ABORT
, "scsi%d: reset aborted issued command(s)\n", H_NO(cmd
));
2943 if (hostdata
->connected
)
2944 dprintk(NDEBUG_ABORT
, "scsi%d: reset aborted a connected command\n", H_NO(cmd
));
2945 if (hostdata
->disconnected_queue
)
2946 dprintk(NDEBUG_ABORT
, "scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd
));
2948 local_irq_save(flags
);
2949 hostdata
->issue_queue
= NULL
;
2950 hostdata
->connected
= NULL
;
2951 hostdata
->disconnected_queue
= NULL
;
2955 for (i
= 0; i
< 8; ++i
)
2956 hostdata
->busy
[i
] = 0;
2958 hostdata
->dma_len
= 0;
2960 local_irq_restore(flags
);
2962 /* we did no complete reset of all commands, so a wakeup is required */