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.
70 * Further development / testing that should be done :
71 * 1. Test linked command handling code after Eric is ready with
72 * the high level code.
75 /* Adapted for the sun3 by Sam Creasey. */
77 #include <scsi/scsi_dbg.h>
78 #include <scsi/scsi_transport_spi.h>
80 #if (NDEBUG & NDEBUG_LISTS)
83 printk("LINE:%d Adding %p to %p\n", \
84 __LINE__, (void*)(x), (void*)(y)); \
88 #define REMOVE(w, x, y, z) \
90 printk("LINE:%d Removing: %p->%p %p->%p \n", \
91 __LINE__, (void*)(w), (void*)(x), \
92 (void*)(y), (void*)(z)); \
98 #define REMOVE(w,x,y,z)
108 * This is a generic 5380 driver. To use it on a different platform,
109 * one simply writes appropriate system specific macros (ie, data
110 * transfer - some PC's will use the I/O bus, 68K's must use
111 * memory mapped) and drops this file in their 'C' wrapper.
113 * As far as command queueing, two queues are maintained for
114 * each 5380 in the system - commands that haven't been issued yet,
115 * and commands that are currently executing. This means that an
116 * unlimited number of commands may be queued, letting
117 * more commands propagate from the higher driver levels giving higher
118 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
119 * allowing multiple commands to propagate all the way to a SCSI-II device
120 * while a command is already executing.
123 * Issues specific to the NCR5380 :
125 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
126 * piece of hardware that requires you to sit in a loop polling for
127 * the REQ signal as long as you are connected. Some devices are
128 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
129 * while doing long seek operations.
131 * The workaround for this is to keep track of devices that have
132 * disconnected. If the device hasn't disconnected, for commands that
133 * should disconnect, we do something like
135 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
137 * Some tweaking of N and M needs to be done. An algorithm based
138 * on "time to data" would give the best results as long as short time
139 * to datas (ie, on the same track) were considered, however these
140 * broken devices are the exception rather than the rule and I'd rather
141 * spend my time optimizing for the normal case.
145 * At the heart of the design is a coroutine, NCR5380_main,
146 * which is started from a workqueue for each NCR5380 host in the
147 * system. It attempts to establish I_T_L or I_T_L_Q nexuses by
148 * removing the commands from the issue queue and calling
149 * NCR5380_select() if a nexus is not established.
151 * Once a nexus is established, the NCR5380_information_transfer()
152 * phase goes through the various phases as instructed by the target.
153 * if the target goes into MSG IN and sends a DISCONNECT message,
154 * the command structure is placed into the per instance disconnected
155 * queue, and NCR5380_main tries to find more work. If the target is
156 * idle for too long, the system will try to sleep.
158 * If a command has disconnected, eventually an interrupt will trigger,
159 * calling NCR5380_intr() which will in turn call NCR5380_reselect
160 * to reestablish a nexus. This will run main if necessary.
162 * On command termination, the done function will be called as
165 * SCSI pointers are maintained in the SCp field of SCSI command
166 * structures, being initialized after the command is connected
167 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
168 * Note that in violation of the standard, an implicit SAVE POINTERS operation
169 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
174 * This file a skeleton Linux SCSI driver for the NCR 5380 series
175 * of chips. To use it, you write an architecture specific functions
176 * and macros and include this file in your driver.
178 * These macros control options :
179 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
180 * for commands that return with a CHECK CONDITION status.
182 * DIFFERENTIAL - if defined, NCR53c81 chips will use external differential
185 * LINKED - if defined, linked commands are supported.
187 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
189 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
191 * These macros MUST be defined :
193 * NCR5380_read(register) - read from the specified register
195 * NCR5380_write(register, value) - write to the specific register
197 * NCR5380_implementation_fields - additional fields needed for this
198 * specific implementation of the NCR5380
200 * Either real DMA *or* pseudo DMA may be implemented
202 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
203 * Note that the DMA setup functions should return the number of bytes
204 * that they were able to program the controller for.
206 * Also note that generic i386/PC versions of these macros are
207 * available as NCR5380_i386_dma_write_setup,
208 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
210 * NCR5380_dma_write_setup(instance, src, count) - initialize
211 * NCR5380_dma_read_setup(instance, dst, count) - initialize
212 * NCR5380_dma_residual(instance); - residual count
215 * NCR5380_pwrite(instance, src, count)
216 * NCR5380_pread(instance, dst, count);
218 * The generic driver is initialized by calling NCR5380_init(instance),
219 * after setting the appropriate host specific fields and ID. If the
220 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
221 * possible) function may be used.
224 /* Macros ease life... :-) */
225 #define SETUP_HOSTDATA(in) \
226 struct NCR5380_hostdata *hostdata = \
227 (struct NCR5380_hostdata *)(in)->hostdata
228 #define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)
230 #define NEXT(cmd) ((struct scsi_cmnd *)(cmd)->host_scribble)
231 #define SET_NEXT(cmd,next) ((cmd)->host_scribble = (void *)(next))
232 #define NEXTADDR(cmd) ((struct scsi_cmnd **)&(cmd)->host_scribble)
234 #define HOSTNO instance->host_no
235 #define H_NO(cmd) (cmd)->device->host->host_no
237 static int do_abort(struct Scsi_Host *);
238 static void do_reset(struct Scsi_Host *);
243 * Functions for handling tagged queuing
244 * =====================================
246 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
248 * Using consecutive numbers for the tags is no good idea in my eyes. There
249 * could be wrong re-usings if the counter (8 bit!) wraps and some early
250 * command has been preempted for a long time. My solution: a bitfield for
251 * remembering used tags.
253 * There's also the problem that each target has a certain queue size, but we
254 * cannot know it in advance :-( We just see a QUEUE_FULL status being
255 * returned. So, in this case, the driver internal queue size assumption is
256 * reduced to the number of active tags if QUEUE_FULL is returned by the
257 * target. The command is returned to the mid-level, but with status changed
258 * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL
261 * We're also not allowed running tagged commands as long as an untagged
262 * command is active. And REQUEST SENSE commands after a contingent allegiance
263 * condition _must_ be untagged. To keep track whether an untagged command has
264 * been issued, the host->busy array is still employed, as it is without
265 * support for tagged queuing.
267 * One could suspect that there are possible race conditions between
268 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
269 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
270 * which already guaranteed to be running at most once. It is also the only
271 * place where tags/LUNs are allocated. So no other allocation can slip
272 * between that pair, there could only happen a reselection, which can free a
273 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
274 * important: the tag bit must be cleared before 'nr_allocated' is decreased.
277 static void __init init_tags(struct NCR5380_hostdata *hostdata)
280 struct tag_alloc *ta;
282 if (!(hostdata->flags & FLAG_TAGGED_QUEUING))
285 for (target = 0; target < 8; ++target) {
286 for (lun = 0; lun < 8; ++lun) {
287 ta = &hostdata->TagAlloc[target][lun];
288 bitmap_zero(ta->allocated, MAX_TAGS);
289 ta->nr_allocated = 0;
290 /* At the beginning, assume the maximum queue size we could
291 * support (MAX_TAGS). This value will be decreased if the target
292 * returns QUEUE_FULL status.
294 ta->queue_size = MAX_TAGS;
300 /* Check if we can issue a command to this LUN: First see if the LUN is marked
301 * busy by an untagged command. If the command should use tagged queuing, also
302 * check that there is a free tag and the target's queue won't overflow. This
303 * function should be called with interrupts disabled to avoid race
307 static int is_lun_busy(struct scsi_cmnd *cmd, int should_be_tagged)
309 u8 lun = cmd->device->lun;
310 SETUP_HOSTDATA(cmd->device->host);
312 if (hostdata->busy[cmd->device->id] & (1 << lun))
314 if (!should_be_tagged ||
315 !(hostdata->flags & FLAG_TAGGED_QUEUING) ||
316 !cmd->device->tagged_supported)
318 if (hostdata->TagAlloc[scmd_id(cmd)][lun].nr_allocated >=
319 hostdata->TagAlloc[scmd_id(cmd)][lun].queue_size) {
320 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d: no free tags\n",
321 H_NO(cmd), cmd->device->id, lun);
328 /* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
329 * must be called before!), or reserve the LUN in 'busy' if the command is
333 static void cmd_get_tag(struct scsi_cmnd *cmd, int should_be_tagged)
335 u8 lun = cmd->device->lun;
336 SETUP_HOSTDATA(cmd->device->host);
338 /* If we or the target don't support tagged queuing, allocate the LUN for
339 * an untagged command.
341 if (!should_be_tagged ||
342 !(hostdata->flags & FLAG_TAGGED_QUEUING) ||
343 !cmd->device->tagged_supported) {
345 hostdata->busy[cmd->device->id] |= (1 << lun);
346 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d now allocated by untagged "
347 "command\n", H_NO(cmd), cmd->device->id, lun);
349 struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun];
351 cmd->tag = find_first_zero_bit(ta->allocated, MAX_TAGS);
352 set_bit(cmd->tag, ta->allocated);
354 dprintk(NDEBUG_TAGS, "scsi%d: using tag %d for target %d lun %d "
355 "(now %d tags in use)\n",
356 H_NO(cmd), cmd->tag, cmd->device->id,
357 lun, ta->nr_allocated);
362 /* Mark the tag of command 'cmd' as free, or in case of an untagged command,
366 static void cmd_free_tag(struct scsi_cmnd *cmd)
368 u8 lun = cmd->device->lun;
369 SETUP_HOSTDATA(cmd->device->host);
371 if (cmd->tag == TAG_NONE) {
372 hostdata->busy[cmd->device->id] &= ~(1 << lun);
373 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %d untagged cmd finished\n",
374 H_NO(cmd), cmd->device->id, lun);
375 } else if (cmd->tag >= MAX_TAGS) {
376 printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n",
377 H_NO(cmd), cmd->tag);
379 struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][lun];
380 clear_bit(cmd->tag, ta->allocated);
382 dprintk(NDEBUG_TAGS, "scsi%d: freed tag %d for target %d lun %d\n",
383 H_NO(cmd), cmd->tag, cmd->device->id, lun);
388 static void free_all_tags(struct NCR5380_hostdata *hostdata)
391 struct tag_alloc *ta;
393 if (!(hostdata->flags & FLAG_TAGGED_QUEUING))
396 for (target = 0; target < 8; ++target) {
397 for (lun = 0; lun < 8; ++lun) {
398 ta = &hostdata->TagAlloc[target][lun];
399 bitmap_zero(ta->allocated, MAX_TAGS);
400 ta->nr_allocated = 0;
405 #endif /* SUPPORT_TAGS */
409 * Function: void merge_contiguous_buffers( struct scsi_cmnd *cmd )
411 * Purpose: Try to merge several scatter-gather requests into one DMA
412 * transfer. This is possible if the scatter buffers lie on
413 * physical contiguous addresses.
415 * Parameters: struct scsi_cmnd *cmd
416 * The command to work on. The first scatter buffer's data are
417 * assumed to be already transferred into ptr/this_residual.
420 static void merge_contiguous_buffers(struct scsi_cmnd *cmd)
422 #if !defined(CONFIG_SUN3)
423 unsigned long endaddr;
424 #if (NDEBUG & NDEBUG_MERGING)
425 unsigned long oldlen = cmd->SCp.this_residual;
429 for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
430 cmd->SCp.buffers_residual &&
431 virt_to_phys(sg_virt(&cmd->SCp.buffer[1])) == endaddr;) {
432 dprintk(NDEBUG_MERGING, "VTOP(%p) == %08lx -> merging\n",
433 page_address(sg_page(&cmd->SCp.buffer[1])), endaddr);
434 #if (NDEBUG & NDEBUG_MERGING)
438 --cmd->SCp.buffers_residual;
439 cmd->SCp.this_residual += cmd->SCp.buffer->length;
440 endaddr += cmd->SCp.buffer->length;
442 #if (NDEBUG & NDEBUG_MERGING)
443 if (oldlen != cmd->SCp.this_residual)
444 dprintk(NDEBUG_MERGING, "merged %d buffers from %p, new length %08x\n",
445 cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
447 #endif /* !defined(CONFIG_SUN3) */
451 * initialize_SCp - init the scsi pointer field
452 * @cmd: command block to set up
454 * Set up the internal fields in the SCSI command.
457 static inline void initialize_SCp(struct scsi_cmnd *cmd)
460 * Initialize the Scsi Pointer field so that all of the commands in the
461 * various queues are valid.
464 if (scsi_bufflen(cmd)) {
465 cmd->SCp.buffer = scsi_sglist(cmd);
466 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
467 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
468 cmd->SCp.this_residual = cmd->SCp.buffer->length;
469 /* ++roman: Try to merge some scatter-buffers if they are at
470 * contiguous physical addresses.
472 merge_contiguous_buffers(cmd);
474 cmd->SCp.buffer = NULL;
475 cmd->SCp.buffers_residual = 0;
477 cmd->SCp.this_residual = 0;
482 * NCR5380_poll_politely - wait for NCR5380 status bits
483 * @instance: controller to poll
484 * @reg: 5380 register to poll
485 * @bit: Bitmask to check
486 * @val: Value required to exit
488 * Polls the NCR5380 in a reasonably efficient manner waiting for
489 * an event to occur, after a short quick poll we begin giving the
490 * CPU back in non IRQ contexts
492 * Returns the value of the register or a negative error code.
495 static int NCR5380_poll_politely(struct Scsi_Host *instance,
496 int reg, int bit, int val, int t)
499 unsigned long end = jiffies + t;
503 r = NCR5380_read(reg);
504 if ((r & bit) == val)
510 while (time_before(jiffies, end)) {
511 r = NCR5380_read(reg);
512 if ((r & bit) == val)
522 #include <linux/delay.h>
529 { SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" },
530 { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" },
531 { SR_SEL, "SEL" }, {0, NULL}
533 {BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}
535 {ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"},
536 {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"},
537 {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"},
540 {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"},
541 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR,
542 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"},
543 {MR_MONITOR_BSY, "MODE MONITOR BSY"},
544 {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"},
549 * NCR5380_print - print scsi bus signals
550 * @instance: adapter state to dump
552 * Print the SCSI bus signals for debugging purposes
555 static void NCR5380_print(struct Scsi_Host *instance)
557 unsigned char status, data, basr, mr, icr, i;
560 local_irq_save(flags);
561 data = NCR5380_read(CURRENT_SCSI_DATA_REG);
562 status = NCR5380_read(STATUS_REG);
563 mr = NCR5380_read(MODE_REG);
564 icr = NCR5380_read(INITIATOR_COMMAND_REG);
565 basr = NCR5380_read(BUS_AND_STATUS_REG);
566 local_irq_restore(flags);
567 printk("STATUS_REG: %02x ", status);
568 for (i = 0; signals[i].mask; ++i)
569 if (status & signals[i].mask)
570 printk(",%s", signals[i].name);
571 printk("\nBASR: %02x ", basr);
572 for (i = 0; basrs[i].mask; ++i)
573 if (basr & basrs[i].mask)
574 printk(",%s", basrs[i].name);
575 printk("\nICR: %02x ", icr);
576 for (i = 0; icrs[i].mask; ++i)
577 if (icr & icrs[i].mask)
578 printk(",%s", icrs[i].name);
579 printk("\nMODE: %02x ", mr);
580 for (i = 0; mrs[i].mask; ++i)
581 if (mr & mrs[i].mask)
582 printk(",%s", mrs[i].name);
590 {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
591 {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
592 {PHASE_UNKNOWN, "UNKNOWN"}
596 * NCR5380_print_phase - show SCSI phase
597 * @instance: adapter to dump
599 * Print the current SCSI phase for debugging purposes
604 static void NCR5380_print_phase(struct Scsi_Host *instance)
606 unsigned char status;
609 status = NCR5380_read(STATUS_REG);
610 if (!(status & SR_REQ))
611 printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO);
613 for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
614 (phases[i].value != (status & PHASE_MASK)); ++i)
616 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name);
623 * ++roman: New scheme of calling NCR5380_main()
625 * If we're not in an interrupt, we can call our main directly, it cannot be
626 * already running. Else, we queue it on a task queue, if not 'main_running'
627 * tells us that a lower level is already executing it. This way,
628 * 'main_running' needs not be protected in a special way.
630 * queue_main() is a utility function for putting our main onto the task
631 * queue, if main_running is false. It should be called only from a
632 * interrupt or bottom half.
635 #include <linux/gfp.h>
636 #include <linux/workqueue.h>
637 #include <linux/interrupt.h>
639 static inline void queue_main(struct NCR5380_hostdata *hostdata)
641 if (!hostdata->main_running) {
642 /* If in interrupt and NCR5380_main() not already running,
643 queue it on the 'immediate' task queue, to be processed
644 immediately after the current interrupt processing has
646 schedule_work(&hostdata->main_task);
648 /* else: nothing to do: the running NCR5380_main() will pick up
649 any newly queued command. */
653 * NCR58380_info - report driver and host information
654 * @instance: relevant scsi host instance
656 * For use as the host template info() handler.
661 static const char *NCR5380_info(struct Scsi_Host *instance)
663 struct NCR5380_hostdata *hostdata = shost_priv(instance);
665 return hostdata->info;
668 static void prepare_info(struct Scsi_Host *instance)
670 struct NCR5380_hostdata *hostdata = shost_priv(instance);
672 snprintf(hostdata->info, sizeof(hostdata->info),
673 "%s, io_port 0x%lx, n_io_port %d, "
674 "base 0x%lx, irq %d, "
675 "can_queue %d, cmd_per_lun %d, "
676 "sg_tablesize %d, this_id %d, "
679 instance->hostt->name, instance->io_port, instance->n_io_port,
680 instance->base, instance->irq,
681 instance->can_queue, instance->cmd_per_lun,
682 instance->sg_tablesize, instance->this_id,
683 hostdata->flags & FLAG_TAGGED_QUEUING ? "TAGGED_QUEUING " : "",
684 hostdata->flags & FLAG_TOSHIBA_DELAY ? "TOSHIBA_DELAY " : "",
701 * NCR5380_print_status - dump controller info
702 * @instance: controller to dump
704 * Print commands in the various queues, called from NCR5380_abort
708 static void lprint_Scsi_Cmnd(struct scsi_cmnd *cmd)
711 unsigned char *command;
712 printk("scsi%d: destination target %d, lun %llu\n",
713 H_NO(cmd), cmd->device->id, cmd->device->lun);
714 printk(KERN_CONT " command = ");
716 printk(KERN_CONT "%2d (0x%02x)", command[0], command[0]);
717 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
718 printk(KERN_CONT " %02x", command[i]);
722 static void __maybe_unused NCR5380_print_status(struct Scsi_Host *instance)
724 struct NCR5380_hostdata *hostdata;
725 struct scsi_cmnd *ptr;
728 NCR5380_dprint(NDEBUG_ANY, instance);
729 NCR5380_dprint_phase(NDEBUG_ANY, instance);
731 hostdata = (struct NCR5380_hostdata *)instance->hostdata;
733 local_irq_save(flags);
734 printk("NCR5380: coroutine is%s running.\n",
735 hostdata->main_running ? "" : "n't");
736 if (!hostdata->connected)
737 printk("scsi%d: no currently connected command\n", HOSTNO);
739 lprint_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected);
740 printk("scsi%d: issue_queue\n", HOSTNO);
741 for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr))
742 lprint_Scsi_Cmnd(ptr);
744 printk("scsi%d: disconnected_queue\n", HOSTNO);
745 for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr;
747 lprint_Scsi_Cmnd(ptr);
749 local_irq_restore(flags);
753 static void show_Scsi_Cmnd(struct scsi_cmnd *cmd, struct seq_file *m)
756 unsigned char *command;
757 seq_printf(m, "scsi%d: destination target %d, lun %llu\n",
758 H_NO(cmd), cmd->device->id, cmd->device->lun);
759 seq_puts(m, " command = ");
761 seq_printf(m, "%2d (0x%02x)", command[0], command[0]);
762 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
763 seq_printf(m, " %02x", command[i]);
767 static int __maybe_unused NCR5380_show_info(struct seq_file *m,
768 struct Scsi_Host *instance)
770 struct NCR5380_hostdata *hostdata;
771 struct scsi_cmnd *ptr;
774 hostdata = (struct NCR5380_hostdata *)instance->hostdata;
776 local_irq_save(flags);
777 seq_printf(m, "NCR5380: coroutine is%s running.\n",
778 hostdata->main_running ? "" : "n't");
779 if (!hostdata->connected)
780 seq_printf(m, "scsi%d: no currently connected command\n", HOSTNO);
782 show_Scsi_Cmnd((struct scsi_cmnd *) hostdata->connected, m);
783 seq_printf(m, "scsi%d: issue_queue\n", HOSTNO);
784 for (ptr = (struct scsi_cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr))
785 show_Scsi_Cmnd(ptr, m);
787 seq_printf(m, "scsi%d: disconnected_queue\n", HOSTNO);
788 for (ptr = (struct scsi_cmnd *) hostdata->disconnected_queue; ptr;
790 show_Scsi_Cmnd(ptr, m);
792 local_irq_restore(flags);
797 * NCR5380_init - initialise an NCR5380
798 * @instance: adapter to configure
799 * @flags: control flags
801 * Initializes *instance and corresponding 5380 chip,
802 * with flags OR'd into the initial flags value.
804 * Notes : I assume that the host, hostno, and id bits have been
805 * set correctly. I don't care about the irq and other fields.
807 * Returns 0 for success
810 static int __init NCR5380_init(struct Scsi_Host *instance, int flags)
813 SETUP_HOSTDATA(instance);
815 hostdata->host = instance;
816 hostdata->id_mask = 1 << instance->this_id;
817 hostdata->id_higher_mask = 0;
818 for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
819 if (i > hostdata->id_mask)
820 hostdata->id_higher_mask |= i;
821 for (i = 0; i < 8; ++i)
822 hostdata->busy[i] = 0;
826 #if defined (REAL_DMA)
827 hostdata->dma_len = 0;
829 hostdata->connected = NULL;
830 hostdata->issue_queue = NULL;
831 hostdata->disconnected_queue = NULL;
832 hostdata->flags = flags;
834 INIT_WORK(&hostdata->main_task, NCR5380_main);
836 prepare_info(instance);
838 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
839 NCR5380_write(MODE_REG, MR_BASE);
840 NCR5380_write(TARGET_COMMAND_REG, 0);
841 NCR5380_write(SELECT_ENABLE_REG, 0);
847 * NCR5380_maybe_reset_bus - Detect and correct bus wedge problems.
848 * @instance: adapter to check
850 * If the system crashed, it may have crashed with a connected target and
851 * the SCSI bus busy. Check for BUS FREE phase. If not, try to abort the
852 * currently established nexus, which we know nothing about. Failing that
855 * Note that a bus reset will cause the chip to assert IRQ.
857 * Returns 0 if successful, otherwise -ENXIO.
860 static int NCR5380_maybe_reset_bus(struct Scsi_Host *instance)
862 struct NCR5380_hostdata *hostdata = shost_priv(instance);
865 for (pass = 1; (NCR5380_read(STATUS_REG) & SR_BSY) && pass <= 6; ++pass) {
870 shost_printk(KERN_ERR, instance, "SCSI bus busy, waiting up to five seconds\n");
871 NCR5380_poll_politely(instance,
872 STATUS_REG, SR_BSY, 0, 5 * HZ);
875 shost_printk(KERN_ERR, instance, "bus busy, attempting abort\n");
879 shost_printk(KERN_ERR, instance, "bus busy, attempting reset\n");
881 /* Wait after a reset; the SCSI standard calls for
882 * 250ms, we wait 500ms to be on the safe side.
883 * But some Toshiba CD-ROMs need ten times that.
885 if (hostdata->flags & FLAG_TOSHIBA_DELAY)
891 shost_printk(KERN_ERR, instance, "bus locked solid\n");
899 * NCR5380_exit - remove an NCR5380
900 * @instance: adapter to remove
902 * Assumes that no more work can be queued (e.g. by NCR5380_intr).
905 static void NCR5380_exit(struct Scsi_Host *instance)
907 struct NCR5380_hostdata *hostdata = shost_priv(instance);
909 cancel_work_sync(&hostdata->main_task);
913 * NCR5380_queue_command - queue a command
914 * @instance: the relevant SCSI adapter
917 * cmd is added to the per instance issue_queue, with minor
918 * twiddling done to the host specific fields of cmd. If the
919 * main coroutine is not running, it is restarted.
922 static int NCR5380_queue_command(struct Scsi_Host *instance,
923 struct scsi_cmnd *cmd)
925 struct NCR5380_hostdata *hostdata = shost_priv(instance);
926 struct scsi_cmnd *tmp;
929 #if (NDEBUG & NDEBUG_NO_WRITE)
930 switch (cmd->cmnd[0]) {
933 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
935 cmd->result = (DID_ERROR << 16);
939 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
942 * We use the host_scribble field as a pointer to the next command
950 * Insert the cmd into the issue queue. Note that REQUEST SENSE
951 * commands are added to the head of the queue since any command will
952 * clear the contingent allegiance condition that exists and the
953 * sense data is only guaranteed to be valid while the condition exists.
956 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
957 * Otherwise a running NCR5380_main may steal the lock.
958 * Lock before actually inserting due to fairness reasons explained in
959 * atari_scsi.c. If we insert first, then it's impossible for this driver
960 * to release the lock.
961 * Stop timer for this command while waiting for the lock, or timeouts
962 * may happen (and they really do), and it's no good if the command doesn't
963 * appear in any of the queues.
964 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
965 * because also a timer int can trigger an abort or reset, which would
966 * alter queues and touch the lock.
968 if (!NCR5380_acquire_dma_irq(instance))
969 return SCSI_MLQUEUE_HOST_BUSY;
971 local_irq_save(flags);
974 * Insert the cmd into the issue queue. Note that REQUEST SENSE
975 * commands are added to the head of the queue since any command will
976 * clear the contingent allegiance condition that exists and the
977 * sense data is only guaranteed to be valid while the condition exists.
980 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
981 LIST(cmd, hostdata->issue_queue);
982 SET_NEXT(cmd, hostdata->issue_queue);
983 hostdata->issue_queue = cmd;
985 for (tmp = (struct scsi_cmnd *)hostdata->issue_queue;
986 NEXT(tmp); tmp = NEXT(tmp))
991 local_irq_restore(flags);
993 dprintk(NDEBUG_QUEUES, "scsi%d: command added to %s of queue\n", H_NO(cmd),
994 (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
996 /* If queue_command() is called from an interrupt (real one or bottom
997 * half), we let queue_main() do the job of taking care about main. If it
998 * is already running, this is a no-op, else main will be queued.
1000 * If we're not in an interrupt, we can call NCR5380_main()
1001 * unconditionally, because it cannot be already running.
1003 if (in_interrupt() || irqs_disabled())
1004 queue_main(hostdata);
1006 NCR5380_main(&hostdata->main_task);
1010 static inline void maybe_release_dma_irq(struct Scsi_Host *instance)
1012 struct NCR5380_hostdata *hostdata = shost_priv(instance);
1014 /* Caller does the locking needed to set & test these data atomically */
1015 if (!hostdata->disconnected_queue &&
1016 !hostdata->issue_queue &&
1017 !hostdata->connected &&
1018 !hostdata->retain_dma_intr)
1019 NCR5380_release_dma_irq(instance);
1023 * NCR5380_main - NCR state machines
1025 * NCR5380_main is a coroutine that runs as long as more work can
1026 * be done on the NCR5380 host adapters in a system. Both
1027 * NCR5380_queue_command() and NCR5380_intr() will try to start it
1028 * in case it is not running.
1030 * Locks: called as its own thread with no locks held.
1033 static void NCR5380_main(struct work_struct *work)
1035 struct NCR5380_hostdata *hostdata =
1036 container_of(work, struct NCR5380_hostdata, main_task);
1037 struct Scsi_Host *instance = hostdata->host;
1038 struct scsi_cmnd *tmp, *prev;
1040 unsigned long flags;
1043 * We run (with interrupts disabled) until we're sure that none of
1044 * the host adapters have anything that can be done, at which point
1045 * we set main_running to 0 and exit.
1047 * Interrupts are enabled before doing various other internal
1048 * instructions, after we've decided that we need to run through
1051 * this should prevent any race conditions.
1053 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1054 * because also a timer int can trigger an abort or reset, which can
1055 * alter queues and touch the Falcon lock.
1058 /* Tell int handlers main() is now already executing. Note that
1059 no races are possible here. If an int comes in before
1060 'main_running' is set here, and queues/executes main via the
1061 task queue, it doesn't do any harm, just this instance of main
1062 won't find any work left to do. */
1063 if (hostdata->main_running)
1065 hostdata->main_running = 1;
1067 local_save_flags(flags);
1069 local_irq_disable(); /* Freeze request queues */
1072 if (!hostdata->connected) {
1073 dprintk(NDEBUG_MAIN, "scsi%d: not connected\n", HOSTNO);
1075 * Search through the issue_queue for a command destined
1076 * for a target that's not busy.
1078 #if (NDEBUG & NDEBUG_LISTS)
1079 for (tmp = (struct scsi_cmnd *) hostdata->issue_queue, prev = NULL;
1080 tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
1082 /*printk("%p ", tmp);*/
1083 if ((tmp == prev) && tmp)
1085 /* else printk("\n"); */
1087 for (tmp = (struct scsi_cmnd *) hostdata->issue_queue,
1088 prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) {
1089 u8 lun = tmp->device->lun;
1091 dprintk(NDEBUG_LISTS,
1092 "MAIN tmp=%p target=%d busy=%d lun=%d\n",
1093 tmp, scmd_id(tmp), hostdata->busy[scmd_id(tmp)],
1095 /* When we find one, remove it from the issue queue. */
1096 /* ++guenther: possible race with Falcon locking */
1099 !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
1101 !(hostdata->busy[tmp->device->id] & (1 << lun))
1104 /* ++guenther: just to be sure, this must be atomic */
1105 local_irq_disable();
1107 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1108 SET_NEXT(prev, NEXT(tmp));
1110 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
1111 hostdata->issue_queue = NEXT(tmp);
1113 SET_NEXT(tmp, NULL);
1114 hostdata->retain_dma_intr++;
1116 /* reenable interrupts after finding one */
1117 local_irq_restore(flags);
1120 * Attempt to establish an I_T_L nexus here.
1121 * On success, instance->hostdata->connected is set.
1122 * On failure, we must add the command back to the
1123 * issue queue so we can keep trying.
1125 dprintk(NDEBUG_MAIN, "scsi%d: main(): command for target %d "
1126 "lun %d removed from issue_queue\n",
1127 HOSTNO, tmp->device->id, lun);
1129 * REQUEST SENSE commands are issued without tagged
1130 * queueing, even on SCSI-II devices because the
1131 * contingent allegiance condition exists for the
1134 /* ++roman: ...and the standard also requires that
1135 * REQUEST SENSE command are untagged.
1139 cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE);
1141 if (!NCR5380_select(instance, tmp)) {
1142 local_irq_disable();
1143 hostdata->retain_dma_intr--;
1144 /* release if target did not response! */
1145 maybe_release_dma_irq(instance);
1146 local_irq_restore(flags);
1149 local_irq_disable();
1150 LIST(tmp, hostdata->issue_queue);
1151 SET_NEXT(tmp, hostdata->issue_queue);
1152 hostdata->issue_queue = tmp;
1156 hostdata->retain_dma_intr--;
1157 local_irq_restore(flags);
1158 dprintk(NDEBUG_MAIN, "scsi%d: main(): select() failed, "
1159 "returned to issue_queue\n", HOSTNO);
1160 if (hostdata->connected)
1163 } /* if target/lun/target queue is not busy */
1164 } /* for issue_queue */
1165 } /* if (!hostdata->connected) */
1167 if (hostdata->connected
1169 && !hostdata->dma_len
1172 local_irq_restore(flags);
1173 dprintk(NDEBUG_MAIN, "scsi%d: main: performing information transfer\n",
1175 NCR5380_information_transfer(instance);
1176 dprintk(NDEBUG_MAIN, "scsi%d: main: done set false\n", HOSTNO);
1181 /* Better allow ints _after_ 'main_running' has been cleared, else
1182 an interrupt could believe we'll pick up the work it left for
1183 us, but we won't see it anymore here... */
1184 hostdata->main_running = 0;
1185 local_irq_restore(flags);
1191 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1193 * Purpose : Called by interrupt handler when DMA finishes or a phase
1194 * mismatch occurs (which would finish the DMA transfer).
1196 * Inputs : instance - this instance of the NCR5380.
1200 static void NCR5380_dma_complete(struct Scsi_Host *instance)
1202 SETUP_HOSTDATA(instance);
1204 unsigned char **data;
1205 volatile int *count;
1206 int saved_data = 0, overrun = 0;
1209 if (!hostdata->connected) {
1210 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
1211 "no connected cmd\n", HOSTNO);
1215 if (hostdata->read_overruns) {
1216 p = hostdata->connected->SCp.phase;
1219 if ((NCR5380_read(BUS_AND_STATUS_REG) &
1220 (BASR_PHASE_MATCH|BASR_ACK)) ==
1221 (BASR_PHASE_MATCH|BASR_ACK)) {
1222 saved_data = NCR5380_read(INPUT_DATA_REG);
1224 dprintk(NDEBUG_DMA, "scsi%d: read overrun handled\n", HOSTNO);
1229 dprintk(NDEBUG_DMA, "scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1230 HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
1231 NCR5380_read(STATUS_REG));
1233 #if defined(CONFIG_SUN3)
1234 if ((sun3scsi_dma_finish(rq_data_dir(hostdata->connected->request)))) {
1235 pr_err("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n",
1240 /* make sure we're not stuck in a data phase */
1241 if ((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH | BASR_ACK)) ==
1242 (BASR_PHASE_MATCH | BASR_ACK)) {
1243 pr_err("scsi%d: BASR %02x\n", instance->host_no,
1244 NCR5380_read(BUS_AND_STATUS_REG));
1245 pr_err("scsi%d: bus stuck in data phase -- probably a single byte overrun!\n",
1251 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1252 NCR5380_write(MODE_REG, MR_BASE);
1253 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1255 transferred = hostdata->dma_len - NCR5380_dma_residual(instance);
1256 hostdata->dma_len = 0;
1258 data = (unsigned char **)&hostdata->connected->SCp.ptr;
1259 count = &hostdata->connected->SCp.this_residual;
1260 *data += transferred;
1261 *count -= transferred;
1263 if (hostdata->read_overruns) {
1266 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
1267 cnt = toPIO = hostdata->read_overruns;
1269 dprintk(NDEBUG_DMA, "Got an input overrun, using saved byte\n");
1270 *(*data)++ = saved_data;
1275 dprintk(NDEBUG_DMA, "Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
1276 NCR5380_transfer_pio(instance, &p, &cnt, data);
1277 *count -= toPIO - cnt;
1281 #endif /* REAL_DMA */
1285 * NCR5380_intr - generic NCR5380 irq handler
1286 * @irq: interrupt number
1287 * @dev_id: device info
1289 * Handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1290 * from the disconnected queue, and restarting NCR5380_main()
1294 static irqreturn_t NCR5380_intr(int irq, void *dev_id)
1296 struct Scsi_Host *instance = dev_id;
1297 int done = 1, handled = 0;
1300 dprintk(NDEBUG_INTR, "scsi%d: NCR5380 irq triggered\n", HOSTNO);
1302 /* Look for pending interrupts */
1303 basr = NCR5380_read(BUS_AND_STATUS_REG);
1304 dprintk(NDEBUG_INTR, "scsi%d: BASR=%02x\n", HOSTNO, basr);
1305 /* dispatch to appropriate routine if found and done=0 */
1306 if (basr & BASR_IRQ) {
1307 NCR5380_dprint(NDEBUG_INTR, instance);
1308 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
1310 dprintk(NDEBUG_INTR, "scsi%d: SEL interrupt\n", HOSTNO);
1311 NCR5380_reselect(instance);
1312 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1313 } else if (basr & BASR_PARITY_ERROR) {
1314 dprintk(NDEBUG_INTR, "scsi%d: PARITY interrupt\n", HOSTNO);
1315 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1316 } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1317 dprintk(NDEBUG_INTR, "scsi%d: RESET interrupt\n", HOSTNO);
1318 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1321 * The rest of the interrupt conditions can occur only during a
1325 #if defined(REAL_DMA)
1327 * We should only get PHASE MISMATCH and EOP interrupts if we have
1328 * DMA enabled, so do a sanity check based on the current setting
1329 * of the MODE register.
1332 if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
1333 ((basr & BASR_END_DMA_TRANSFER) ||
1334 !(basr & BASR_PHASE_MATCH))) {
1336 dprintk(NDEBUG_INTR, "scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1337 NCR5380_dma_complete( instance );
1340 #endif /* REAL_DMA */
1342 /* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1343 if (basr & BASR_PHASE_MATCH)
1344 dprintk(NDEBUG_INTR, "scsi%d: unknown interrupt, "
1345 "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1346 HOSTNO, basr, NCR5380_read(MODE_REG),
1347 NCR5380_read(STATUS_REG));
1348 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1349 #ifdef SUN3_SCSI_VME
1350 dregs->csr |= CSR_DMA_ENABLE;
1353 } /* if !(SELECTION || PARITY) */
1355 } /* BASR & IRQ */ else {
1356 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
1357 "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
1358 NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG));
1359 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1360 #ifdef SUN3_SCSI_VME
1361 dregs->csr |= CSR_DMA_ENABLE;
1366 dprintk(NDEBUG_INTR, "scsi%d: in int routine, calling main\n", HOSTNO);
1367 /* Put a call to NCR5380_main() on the queue... */
1368 queue_main(shost_priv(instance));
1370 return IRQ_RETVAL(handled);
1374 * Function : int NCR5380_select(struct Scsi_Host *instance,
1375 * struct scsi_cmnd *cmd)
1377 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1378 * including ARBITRATION, SELECTION, and initial message out for
1379 * IDENTIFY and queue messages.
1381 * Inputs : instance - instantiation of the 5380 driver on which this
1382 * target lives, cmd - SCSI command to execute.
1384 * Returns : -1 if selection failed but should be retried.
1385 * 0 if selection failed and should not be retried.
1386 * 0 if selection succeeded completely (hostdata->connected == cmd).
1389 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1390 * with registers as they should have been on entry - ie
1391 * SELECT_ENABLE will be set appropriately, the NCR5380
1392 * will cease to drive any SCSI bus signals.
1394 * If successful : I_T_L or I_T_L_Q nexus will be established,
1395 * instance->connected will be set to cmd.
1396 * SELECT interrupt will be disabled.
1398 * If failed (no target) : cmd->scsi_done() will be called, and the
1399 * cmd->result host byte set to DID_BAD_TARGET.
1402 static int NCR5380_select(struct Scsi_Host *instance, struct scsi_cmnd *cmd)
1404 SETUP_HOSTDATA(instance);
1405 unsigned char tmp[3], phase;
1406 unsigned char *data;
1408 unsigned long timeout;
1409 unsigned long flags;
1411 NCR5380_dprint(NDEBUG_ARBITRATION, instance);
1412 dprintk(NDEBUG_ARBITRATION, "scsi%d: starting arbitration, id = %d\n", HOSTNO,
1416 * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1417 * data bus during SELECTION.
1420 local_irq_save(flags);
1421 if (hostdata->connected) {
1422 local_irq_restore(flags);
1425 NCR5380_write(TARGET_COMMAND_REG, 0);
1428 * Start arbitration.
1431 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1432 NCR5380_write(MODE_REG, MR_ARBITRATE);
1434 local_irq_restore(flags);
1436 /* Wait for arbitration logic to complete */
1437 #if defined(NCR_TIMEOUT)
1439 unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
1441 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
1442 time_before(jiffies, timeout) && !hostdata->connected)
1444 if (time_after_eq(jiffies, timeout)) {
1445 printk("scsi : arbitration timeout at %d\n", __LINE__);
1446 NCR5380_write(MODE_REG, MR_BASE);
1447 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1451 #else /* NCR_TIMEOUT */
1452 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
1453 !hostdata->connected)
1457 dprintk(NDEBUG_ARBITRATION, "scsi%d: arbitration complete\n", HOSTNO);
1459 if (hostdata->connected) {
1460 NCR5380_write(MODE_REG, MR_BASE);
1464 * The arbitration delay is 2.2us, but this is a minimum and there is
1465 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1466 * the integral nature of udelay().
1472 /* Check for lost arbitration */
1473 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1474 (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
1475 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1476 hostdata->connected) {
1477 NCR5380_write(MODE_REG, MR_BASE);
1478 dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1483 /* after/during arbitration, BSY should be asserted.
1484 IBM DPES-31080 Version S31Q works now */
1485 /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
1486 NCR5380_write(INITIATOR_COMMAND_REG,
1487 ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY);
1489 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1490 hostdata->connected) {
1491 NCR5380_write(MODE_REG, MR_BASE);
1492 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1493 dprintk(NDEBUG_ARBITRATION, "scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1499 * Again, bus clear + bus settle time is 1.2us, however, this is
1500 * a minimum so we'll udelay ceil(1.2)
1503 if (hostdata->flags & FLAG_TOSHIBA_DELAY)
1508 if (hostdata->connected) {
1509 NCR5380_write(MODE_REG, MR_BASE);
1510 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1514 dprintk(NDEBUG_ARBITRATION, "scsi%d: won arbitration\n", HOSTNO);
1517 * Now that we have won arbitration, start Selection process, asserting
1518 * the host and target ID's on the SCSI bus.
1521 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id)));
1524 * Raise ATN while SEL is true before BSY goes false from arbitration,
1525 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1526 * phase immediately after selection.
1529 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY |
1530 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL ));
1531 NCR5380_write(MODE_REG, MR_BASE);
1534 * Reselect interrupts must be turned off prior to the dropping of BSY,
1535 * otherwise we will trigger an interrupt.
1538 if (hostdata->connected) {
1539 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1543 NCR5380_write(SELECT_ENABLE_REG, 0);
1546 * The initiator shall then wait at least two deskew delays and release
1549 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1552 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA |
1553 ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1556 * Something weird happens when we cease to drive BSY - looks
1557 * like the board/chip is letting us do another read before the
1558 * appropriate propagation delay has expired, and we're confusing
1559 * a BSY signal from ourselves as the target's response to SELECTION.
1561 * A small delay (the 'C++' frontend breaks the pipeline with an
1562 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1563 * tighter 'C' code breaks and requires this) solves the problem -
1564 * the 1 us delay is arbitrary, and only used because this delay will
1565 * be the same on other platforms and since it works here, it should
1568 * wingel suggests that this could be due to failing to wait
1574 dprintk(NDEBUG_SELECTION, "scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
1577 * The SCSI specification calls for a 250 ms timeout for the actual
1581 timeout = jiffies + msecs_to_jiffies(250);
1584 * XXX very interesting - we're seeing a bounce where the BSY we
1585 * asserted is being reflected / still asserted (propagation delay?)
1586 * and it's detecting as true. Sigh.
1590 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1591 * IO while SEL is true. But again, there are some disks out the in the
1592 * world that do that nevertheless. (Somebody claimed that this announces
1593 * reselection capability of the target.) So we better skip that test and
1594 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-)
1597 while (time_before(jiffies, timeout) &&
1598 !(NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO)))
1601 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1602 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1603 NCR5380_reselect(instance);
1604 printk(KERN_ERR "scsi%d: reselection after won arbitration?\n",
1606 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1610 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY))
1615 * No less than two deskew delays after the initiator detects the
1616 * BSY signal is true, it shall release the SEL signal and may
1617 * change the DATA BUS. -wingel
1622 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1624 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1625 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1626 cmd->result = DID_BAD_TARGET << 16;
1630 cmd->scsi_done(cmd);
1631 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1632 dprintk(NDEBUG_SELECTION, "scsi%d: target did not respond within 250ms\n", HOSTNO);
1637 * Since we followed the SCSI spec, and raised ATN while SEL
1638 * was true but before BSY was false during selection, the information
1639 * transfer phase should be a MESSAGE OUT phase so that we can send the
1642 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1643 * message (2 bytes) with a tag ID that we increment with every command
1644 * until it wraps back to 0.
1646 * XXX - it turns out that there are some broken SCSI-II devices,
1647 * which claim to support tagged queuing but fail when more than
1648 * some number of commands are issued at once.
1651 /* Wait for start of REQ/ACK handshake */
1652 while (!(NCR5380_read(STATUS_REG) & SR_REQ))
1655 dprintk(NDEBUG_SELECTION, "scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1656 HOSTNO, cmd->device->id);
1657 tmp[0] = IDENTIFY(1, cmd->device->lun);
1660 if (cmd->tag != TAG_NONE) {
1661 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
1669 #endif /* SUPPORT_TAGS */
1671 /* Send message(s) */
1673 phase = PHASE_MSGOUT;
1674 NCR5380_transfer_pio(instance, &phase, &len, &data);
1675 dprintk(NDEBUG_SELECTION, "scsi%d: nexus established.\n", HOSTNO);
1676 /* XXX need to handle errors here */
1677 hostdata->connected = cmd;
1678 #ifndef SUPPORT_TAGS
1679 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1681 #ifdef SUN3_SCSI_VME
1682 dregs->csr |= CSR_INTR;
1685 initialize_SCp(cmd);
1691 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1692 * unsigned char *phase, int *count, unsigned char **data)
1694 * Purpose : transfers data in given phase using polled I/O
1696 * Inputs : instance - instance of driver, *phase - pointer to
1697 * what phase is expected, *count - pointer to number of
1698 * bytes to transfer, **data - pointer to data pointer.
1700 * Returns : -1 when different phase is entered without transferring
1701 * maximum number of bytes, 0 if all bytes are transferred or exit
1704 * Also, *phase, *count, *data are modified in place.
1706 * XXX Note : handling for bus free may be useful.
1710 * Note : this code is not as quick as it could be, however it
1711 * IS 100% reliable, and for the actual data transfer where speed
1712 * counts, we will always do a pseudo DMA or DMA transfer.
1715 static int NCR5380_transfer_pio(struct Scsi_Host *instance,
1716 unsigned char *phase, int *count,
1717 unsigned char **data)
1719 register unsigned char p = *phase, tmp;
1720 register int c = *count;
1721 register unsigned char *d = *data;
1724 * The NCR5380 chip will only drive the SCSI bus when the
1725 * phase specified in the appropriate bits of the TARGET COMMAND
1726 * REGISTER match the STATUS REGISTER
1729 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1733 * Wait for assertion of REQ, after which the phase bits will be
1736 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1739 dprintk(NDEBUG_HANDSHAKE, "scsi%d: REQ detected\n", HOSTNO);
1741 /* Check for phase mismatch */
1742 if ((tmp & PHASE_MASK) != p) {
1743 dprintk(NDEBUG_PIO, "scsi%d: phase mismatch\n", HOSTNO);
1744 NCR5380_dprint_phase(NDEBUG_PIO, instance);
1748 /* Do actual transfer from SCSI bus to / from memory */
1750 NCR5380_write(OUTPUT_DATA_REG, *d);
1752 *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1757 * The SCSI standard suggests that in MSGOUT phase, the initiator
1758 * should drop ATN on the last byte of the message phase
1759 * after REQ has been asserted for the handshake but before
1760 * the initiator raises ACK.
1764 if (!((p & SR_MSG) && c > 1)) {
1765 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1766 NCR5380_dprint(NDEBUG_PIO, instance);
1767 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1768 ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1770 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1771 ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1772 NCR5380_dprint(NDEBUG_PIO, instance);
1773 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1774 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1777 NCR5380_dprint(NDEBUG_PIO, instance);
1778 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1781 while (NCR5380_read(STATUS_REG) & SR_REQ)
1784 dprintk(NDEBUG_HANDSHAKE, "scsi%d: req false, handshake complete\n", HOSTNO);
1787 * We have several special cases to consider during REQ/ACK handshaking :
1788 * 1. We were in MSGOUT phase, and we are on the last byte of the
1789 * message. ATN must be dropped as ACK is dropped.
1791 * 2. We are in a MSGIN phase, and we are on the last byte of the
1792 * message. We must exit with ACK asserted, so that the calling
1793 * code may raise ATN before dropping ACK to reject the message.
1795 * 3. ACK and ATN are clear and the target may proceed as normal.
1797 if (!(p == PHASE_MSGIN && c == 1)) {
1798 if (p == PHASE_MSGOUT && c > 1)
1799 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1801 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1805 dprintk(NDEBUG_PIO, "scsi%d: residual %d\n", HOSTNO, c);
1809 tmp = NCR5380_read(STATUS_REG);
1810 /* The phase read from the bus is valid if either REQ is (already)
1811 * asserted or if ACK hasn't been released yet. The latter is the case if
1812 * we're in MSGIN and all wanted bytes have been received.
1814 if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
1815 *phase = tmp & PHASE_MASK;
1817 *phase = PHASE_UNKNOWN;
1819 if (!c || (*phase == p))
1826 * do_reset - issue a reset command
1827 * @instance: adapter to reset
1829 * Issue a reset sequence to the NCR5380 and try and get the bus
1830 * back into sane shape.
1832 * This clears the reset interrupt flag because there may be no handler for
1833 * it. When the driver is initialized, the NCR5380_intr() handler has not yet
1834 * been installed. And when in EH we may have released the ST DMA interrupt.
1837 static void do_reset(struct Scsi_Host *instance)
1839 unsigned long flags;
1841 local_irq_save(flags);
1842 NCR5380_write(TARGET_COMMAND_REG,
1843 PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK));
1844 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
1846 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1847 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1848 local_irq_restore(flags);
1852 * Function : do_abort (Scsi_Host *host)
1854 * Purpose : abort the currently established nexus. Should only be
1855 * called from a routine which can drop into a
1857 * Returns : 0 on success, -1 on failure.
1860 static int do_abort(struct Scsi_Host *instance)
1862 unsigned char tmp, *msgptr, phase;
1865 /* Request message out phase */
1866 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1869 * Wait for the target to indicate a valid phase by asserting
1870 * REQ. Once this happens, we'll have either a MSGOUT phase
1871 * and can immediately send the ABORT message, or we'll have some
1872 * other phase and will have to source/sink data.
1874 * We really don't care what value was on the bus or what value
1875 * the target sees, so we just handshake.
1878 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1881 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1883 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1884 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
1886 while (NCR5380_read(STATUS_REG) & SR_REQ)
1888 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1894 phase = PHASE_MSGOUT;
1895 NCR5380_transfer_pio(instance, &phase, &len, &msgptr);
1898 * If we got here, and the command completed successfully,
1899 * we're about to go into bus free state.
1902 return len ? -1 : 0;
1905 #if defined(REAL_DMA)
1907 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1908 * unsigned char *phase, int *count, unsigned char **data)
1910 * Purpose : transfers data in given phase using either real
1913 * Inputs : instance - instance of driver, *phase - pointer to
1914 * what phase is expected, *count - pointer to number of
1915 * bytes to transfer, **data - pointer to data pointer.
1917 * Returns : -1 when different phase is entered without transferring
1918 * maximum number of bytes, 0 if all bytes or transferred or exit
1921 * Also, *phase, *count, *data are modified in place.
1926 static int NCR5380_transfer_dma(struct Scsi_Host *instance,
1927 unsigned char *phase, int *count,
1928 unsigned char **data)
1930 SETUP_HOSTDATA(instance);
1931 register int c = *count;
1932 register unsigned char p = *phase;
1933 unsigned long flags;
1935 #if defined(CONFIG_SUN3)
1937 if (!sun3_dma_setup_done) {
1938 pr_err("scsi%d: transfer_dma without setup!\n",
1942 hostdata->dma_len = c;
1944 dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1945 instance->host_no, (p & SR_IO) ? "reading" : "writing",
1946 c, (p & SR_IO) ? "to" : "from", *data);
1948 /* netbsd turns off ints here, why not be safe and do it too */
1949 local_irq_save(flags);
1951 /* send start chain */
1952 sun3scsi_dma_start(c, *data);
1955 NCR5380_write(TARGET_COMMAND_REG, 1);
1956 NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1957 NCR5380_write(INITIATOR_COMMAND_REG, 0);
1958 NCR5380_write(MODE_REG,
1959 (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR));
1960 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1962 NCR5380_write(TARGET_COMMAND_REG, 0);
1963 NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1964 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_DATA);
1965 NCR5380_write(MODE_REG,
1966 (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR));
1967 NCR5380_write(START_DMA_SEND_REG, 0);
1970 #ifdef SUN3_SCSI_VME
1971 dregs->csr |= CSR_DMA_ENABLE;
1974 local_irq_restore(flags);
1976 sun3_dma_active = 1;
1978 #else /* !defined(CONFIG_SUN3) */
1979 register unsigned char *d = *data;
1982 if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1987 if (hostdata->read_overruns && (p & SR_IO))
1988 c -= hostdata->read_overruns;
1990 dprintk(NDEBUG_DMA, "scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1991 HOSTNO, (p & SR_IO) ? "reading" : "writing",
1992 c, (p & SR_IO) ? "to" : "from", d);
1994 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1997 NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1998 #endif /* def REAL_DMA */
2000 if (!(hostdata->flags & FLAG_LATE_DMA_SETUP)) {
2001 /* On the Medusa, it is a must to initialize the DMA before
2002 * starting the NCR. This is also the cleaner way for the TT.
2004 local_irq_save(flags);
2005 hostdata->dma_len = (p & SR_IO) ?
2006 NCR5380_dma_read_setup(instance, d, c) :
2007 NCR5380_dma_write_setup(instance, d, c);
2008 local_irq_restore(flags);
2012 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
2014 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
2015 NCR5380_write(START_DMA_SEND_REG, 0);
2018 if (hostdata->flags & FLAG_LATE_DMA_SETUP) {
2019 /* On the Falcon, the DMA setup must be done after the last */
2020 /* NCR access, else the DMA setup gets trashed!
2022 local_irq_save(flags);
2023 hostdata->dma_len = (p & SR_IO) ?
2024 NCR5380_dma_read_setup(instance, d, c) :
2025 NCR5380_dma_write_setup(instance, d, c);
2026 local_irq_restore(flags);
2028 #endif /* !defined(CONFIG_SUN3) */
2032 #endif /* defined(REAL_DMA) */
2035 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
2037 * Purpose : run through the various SCSI phases and do as the target
2038 * directs us to. Operates on the currently connected command,
2039 * instance->connected.
2041 * Inputs : instance, instance for which we are doing commands
2043 * Side effects : SCSI things happen, the disconnected queue will be
2044 * modified if a command disconnects, *instance->connected will
2047 * XXX Note : we need to watch for bus free or a reset condition here
2048 * to recover from an unexpected bus free condition.
2051 static void NCR5380_information_transfer(struct Scsi_Host *instance)
2053 SETUP_HOSTDATA(instance);
2054 unsigned long flags;
2055 unsigned char msgout = NOP;
2058 #if defined(REAL_DMA)
2061 unsigned char *data;
2062 unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2063 struct scsi_cmnd *cmd = (struct scsi_cmnd *) hostdata->connected;
2065 #ifdef SUN3_SCSI_VME
2066 dregs->csr |= CSR_INTR;
2070 tmp = NCR5380_read(STATUS_REG);
2071 /* We only have a valid SCSI phase when REQ is asserted */
2073 phase = (tmp & PHASE_MASK);
2074 if (phase != old_phase) {
2076 NCR5380_dprint_phase(NDEBUG_INFORMATION, instance);
2078 #if defined(CONFIG_SUN3)
2079 if (phase == PHASE_CMDOUT) {
2080 #if defined(REAL_DMA)
2082 unsigned long count;
2084 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2085 count = cmd->SCp.buffer->length;
2086 d = sg_virt(cmd->SCp.buffer);
2088 count = cmd->SCp.this_residual;
2091 /* this command setup for dma yet? */
2092 if ((count >= DMA_MIN_SIZE) && (sun3_dma_setup_done != cmd)) {
2093 if (cmd->request->cmd_type == REQ_TYPE_FS) {
2094 sun3scsi_dma_setup(d, count,
2095 rq_data_dir(cmd->request));
2096 sun3_dma_setup_done = cmd;
2100 #ifdef SUN3_SCSI_VME
2101 dregs->csr |= CSR_INTR;
2104 #endif /* CONFIG_SUN3 */
2106 if (sink && (phase != PHASE_MSGOUT)) {
2107 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2109 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
2111 while (NCR5380_read(STATUS_REG) & SR_REQ)
2113 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2121 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2122 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2123 "aborted\n", HOSTNO);
2126 cmd->result = DID_ERROR << 16;
2127 cmd->scsi_done(cmd);
2132 * If there is no room left in the current buffer in the
2133 * scatter-gather list, move onto the next one.
2136 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2138 --cmd->SCp.buffers_residual;
2139 cmd->SCp.this_residual = cmd->SCp.buffer->length;
2140 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2141 /* ++roman: Try to merge some scatter-buffers if
2142 * they are at contiguous physical addresses.
2144 merge_contiguous_buffers(cmd);
2145 dprintk(NDEBUG_INFORMATION, "scsi%d: %d bytes and %d buffers left\n",
2146 HOSTNO, cmd->SCp.this_residual,
2147 cmd->SCp.buffers_residual);
2151 * The preferred transfer method is going to be
2152 * PSEUDO-DMA for systems that are strictly PIO,
2153 * since we can let the hardware do the handshaking.
2155 * For this to work, we need to know the transfersize
2156 * ahead of time, since the pseudo-DMA code will sit
2157 * in an unconditional loop.
2160 /* ++roman: I suggest, this should be
2162 * instead of leaving REAL_DMA out.
2165 #if defined(REAL_DMA)
2167 #if !defined(CONFIG_SUN3)
2168 !cmd->device->borken &&
2170 (transfersize = NCR5380_dma_xfer_len(instance, cmd, phase)) >= DMA_MIN_SIZE) {
2172 cmd->SCp.phase = phase;
2173 if (NCR5380_transfer_dma(instance, &phase,
2174 &len, (unsigned char **)&cmd->SCp.ptr)) {
2176 * If the watchdog timer fires, all future
2177 * accesses to this device will use the
2179 scmd_printk(KERN_INFO, cmd,
2180 "switching to slow handshake\n");
2181 cmd->device->borken = 1;
2184 cmd->result = DID_ERROR << 16;
2185 cmd->scsi_done(cmd);
2186 /* XXX - need to source or sink data here, as appropriate */
2189 /* ++roman: When using real DMA,
2190 * information_transfer() should return after
2191 * starting DMA since it has nothing more to
2196 cmd->SCp.this_residual -= transfersize - len;
2200 #endif /* defined(REAL_DMA) */
2201 NCR5380_transfer_pio(instance, &phase,
2202 (int *)&cmd->SCp.this_residual,
2203 (unsigned char **)&cmd->SCp.ptr);
2204 #if defined(CONFIG_SUN3) && defined(REAL_DMA)
2205 /* if we had intended to dma that command clear it */
2206 if (sun3_dma_setup_done == cmd)
2207 sun3_dma_setup_done = NULL;
2213 NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */
2214 NCR5380_transfer_pio(instance, &phase, &len, &data);
2215 cmd->SCp.Message = tmp;
2219 * Linking lets us reduce the time required to get the
2220 * next command out to the device, hopefully this will
2221 * mean we don't waste another revolution due to the delays
2222 * required by ARBITRATION and another SELECTION.
2224 * In the current implementation proposal, low level drivers
2225 * merely have to start the next command, pointed to by
2226 * next_link, done() is called as with unlinked commands.
2229 case LINKED_CMD_COMPLETE:
2230 case LINKED_FLG_CMD_COMPLETE:
2231 /* Accept message by clearing ACK */
2232 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2234 dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked command "
2235 "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun);
2237 /* Enable reselect interrupts */
2238 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2240 * Sanity check : A linked command should only terminate
2241 * with one of these messages if there are more linked
2242 * commands available.
2245 if (!cmd->next_link) {
2246 printk(KERN_NOTICE "scsi%d: target %d lun %llu "
2247 "linked command complete, no next_link\n",
2248 HOSTNO, cmd->device->id, cmd->device->lun);
2254 initialize_SCp(cmd->next_link);
2255 /* The next command is still part of this process; copy it
2256 * and don't free it! */
2257 cmd->next_link->tag = cmd->tag;
2258 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2259 dprintk(NDEBUG_LINKED, "scsi%d: target %d lun %llu linked request "
2260 "done, calling scsi_done().\n",
2261 HOSTNO, cmd->device->id, cmd->device->lun);
2262 cmd->scsi_done(cmd);
2263 cmd = hostdata->connected;
2265 #endif /* def LINKED */
2267 case COMMAND_COMPLETE:
2268 /* Accept message by clearing ACK */
2269 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2270 dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d, lun %llu "
2271 "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
2273 local_irq_save(flags);
2274 hostdata->retain_dma_intr++;
2275 hostdata->connected = NULL;
2278 if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
2279 /* Turn a QUEUE FULL status into BUSY, I think the
2280 * mid level cannot handle QUEUE FULL :-( (The
2281 * command is retried after BUSY). Also update our
2282 * queue size to the number of currently issued
2285 /* ++Andreas: the mid level code knows about
2287 struct tag_alloc *ta = &hostdata->TagAlloc[scmd_id(cmd)][cmd->device->lun];
2288 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu returned "
2289 "QUEUE_FULL after %d commands\n",
2290 HOSTNO, cmd->device->id, cmd->device->lun,
2292 if (ta->queue_size > ta->nr_allocated)
2293 ta->nr_allocated = ta->queue_size;
2296 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2298 /* Enable reselect interrupts */
2299 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2302 * I'm not sure what the correct thing to do here is :
2304 * If the command that just executed is NOT a request
2305 * sense, the obvious thing to do is to set the result
2306 * code to the values of the stored parameters.
2308 * If it was a REQUEST SENSE command, we need some way to
2309 * differentiate between the failure code of the original
2310 * and the failure code of the REQUEST sense - the obvious
2311 * case is success, where we fall through and leave the
2312 * result code unchanged.
2314 * The non-obvious place is where the REQUEST SENSE failed
2317 if (cmd->cmnd[0] != REQUEST_SENSE)
2318 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2319 else if (status_byte(cmd->SCp.Status) != GOOD)
2320 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2322 if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2323 hostdata->ses.cmd_len) {
2324 scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2325 hostdata->ses.cmd_len = 0 ;
2328 if ((cmd->cmnd[0] != REQUEST_SENSE) &&
2329 (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2330 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2332 dprintk(NDEBUG_AUTOSENSE, "scsi%d: performing request sense\n", HOSTNO);
2334 LIST(cmd,hostdata->issue_queue);
2335 SET_NEXT(cmd, hostdata->issue_queue);
2336 hostdata->issue_queue = (struct scsi_cmnd *) cmd;
2337 dprintk(NDEBUG_QUEUES, "scsi%d: REQUEST SENSE added to head of "
2338 "issue queue\n", H_NO(cmd));
2340 cmd->scsi_done(cmd);
2343 local_irq_restore(flags);
2345 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2347 * Restore phase bits to 0 so an interrupted selection,
2348 * arbitration can resume.
2350 NCR5380_write(TARGET_COMMAND_REG, 0);
2352 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2355 local_irq_save(flags);
2356 hostdata->retain_dma_intr--;
2357 /* ++roman: For Falcon SCSI, release the lock on the
2358 * ST-DMA here if no other commands are waiting on the
2359 * disconnected queue.
2361 maybe_release_dma_irq(instance);
2362 local_irq_restore(flags);
2364 case MESSAGE_REJECT:
2365 /* Accept message by clearing ACK */
2366 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2367 /* Enable reselect interrupts */
2368 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2369 switch (hostdata->last_message) {
2370 case HEAD_OF_QUEUE_TAG:
2371 case ORDERED_QUEUE_TAG:
2372 case SIMPLE_QUEUE_TAG:
2373 /* The target obviously doesn't support tagged
2374 * queuing, even though it announced this ability in
2375 * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2376 * clear 'tagged_supported' and lock the LUN, since
2377 * the command is treated as untagged further on.
2379 cmd->device->tagged_supported = 0;
2380 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2381 cmd->tag = TAG_NONE;
2382 dprintk(NDEBUG_TAGS, "scsi%d: target %d lun %llu rejected "
2383 "QUEUE_TAG message; tagged queuing "
2385 HOSTNO, cmd->device->id, cmd->device->lun);
2390 /* Accept message by clearing ACK */
2391 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2392 local_irq_save(flags);
2393 cmd->device->disconnect = 1;
2394 LIST(cmd,hostdata->disconnected_queue);
2395 SET_NEXT(cmd, hostdata->disconnected_queue);
2396 hostdata->connected = NULL;
2397 hostdata->disconnected_queue = cmd;
2398 local_irq_restore(flags);
2399 dprintk(NDEBUG_QUEUES, "scsi%d: command for target %d lun %llu was "
2400 "moved from connected to the "
2401 "disconnected_queue\n", HOSTNO,
2402 cmd->device->id, cmd->device->lun);
2404 * Restore phase bits to 0 so an interrupted selection,
2405 * arbitration can resume.
2407 NCR5380_write(TARGET_COMMAND_REG, 0);
2409 /* Enable reselect interrupts */
2410 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2411 /* Wait for bus free to avoid nasty timeouts */
2412 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2414 #ifdef SUN3_SCSI_VME
2415 dregs->csr |= CSR_DMA_ENABLE;
2419 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2420 * operation, in violation of the SCSI spec so we can safely
2421 * ignore SAVE/RESTORE pointers calls.
2423 * Unfortunately, some disks violate the SCSI spec and
2424 * don't issue the required SAVE_POINTERS message before
2425 * disconnecting, and we have to break spec to remain
2429 case RESTORE_POINTERS:
2430 /* Accept message by clearing ACK */
2431 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2432 /* Enable reselect interrupts */
2433 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2435 case EXTENDED_MESSAGE:
2437 * Extended messages are sent in the following format :
2439 * 0 EXTENDED_MESSAGE == 1
2440 * 1 length (includes one byte for code, doesn't
2441 * include first two bytes)
2443 * 3..length+1 arguments
2445 * Start the extended message buffer with the EXTENDED_MESSAGE
2446 * byte, since spi_print_msg() wants the whole thing.
2448 extended_msg[0] = EXTENDED_MESSAGE;
2449 /* Accept first byte by clearing ACK */
2450 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2452 dprintk(NDEBUG_EXTENDED, "scsi%d: receiving extended message\n", HOSTNO);
2455 data = extended_msg + 1;
2456 phase = PHASE_MSGIN;
2457 NCR5380_transfer_pio(instance, &phase, &len, &data);
2458 dprintk(NDEBUG_EXTENDED, "scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2459 (int)extended_msg[1], (int)extended_msg[2]);
2461 if (!len && extended_msg[1] <=
2462 (sizeof(extended_msg) - 1)) {
2463 /* Accept third byte by clearing ACK */
2464 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2465 len = extended_msg[1] - 1;
2466 data = extended_msg + 3;
2467 phase = PHASE_MSGIN;
2469 NCR5380_transfer_pio(instance, &phase, &len, &data);
2470 dprintk(NDEBUG_EXTENDED, "scsi%d: message received, residual %d\n",
2473 switch (extended_msg[2]) {
2476 case EXTENDED_MODIFY_DATA_POINTER:
2477 case EXTENDED_EXTENDED_IDENTIFY:
2481 printk(KERN_NOTICE "scsi%d: error receiving "
2482 "extended message\n", HOSTNO);
2485 printk(KERN_NOTICE "scsi%d: extended message "
2486 "code %02x length %d is too long\n",
2487 HOSTNO, extended_msg[2], extended_msg[1]);
2490 /* Fall through to reject message */
2493 * If we get something weird that we aren't expecting,
2498 printk(KERN_INFO "scsi%d: rejecting message ",
2500 spi_print_msg(extended_msg);
2502 } else if (tmp != EXTENDED_MESSAGE)
2503 scmd_printk(KERN_INFO, cmd,
2504 "rejecting unknown message %02x\n",
2507 scmd_printk(KERN_INFO, cmd,
2508 "rejecting unknown extended message code %02x, length %d\n",
2509 extended_msg[1], extended_msg[0]);
2511 msgout = MESSAGE_REJECT;
2512 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2514 } /* switch (tmp) */
2519 hostdata->last_message = msgout;
2520 NCR5380_transfer_pio(instance, &phase, &len, &data);
2521 if (msgout == ABORT) {
2522 local_irq_save(flags);
2526 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2528 hostdata->connected = NULL;
2529 cmd->result = DID_ERROR << 16;
2530 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2531 maybe_release_dma_irq(instance);
2532 local_irq_restore(flags);
2533 cmd->scsi_done(cmd);
2542 * XXX for performance reasons, on machines with a
2543 * PSEUDO-DMA architecture we should probably
2544 * use the dma transfer function.
2546 NCR5380_transfer_pio(instance, &phase, &len, &data);
2551 NCR5380_transfer_pio(instance, &phase, &len, &data);
2552 cmd->SCp.Status = tmp;
2555 printk("scsi%d: unknown phase\n", HOSTNO);
2556 NCR5380_dprint(NDEBUG_ANY, instance);
2557 } /* switch(phase) */
2558 } /* if (tmp * SR_REQ) */
2563 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2565 * Purpose : does reselection, initializing the instance->connected
2566 * field to point to the scsi_cmnd for which the I_T_L or I_T_L_Q
2567 * nexus has been reestablished,
2569 * Inputs : instance - this instance of the NCR5380.
2574 /* it might eventually prove necessary to do a dma setup on
2575 reselection, but it doesn't seem to be needed now -- sam */
2577 static void NCR5380_reselect(struct Scsi_Host *instance)
2579 SETUP_HOSTDATA(instance);
2580 unsigned char target_mask;
2585 unsigned char msg[3];
2586 int __maybe_unused len;
2587 unsigned char __maybe_unused *data, __maybe_unused phase;
2588 struct scsi_cmnd *tmp = NULL, *prev;
2591 * Disable arbitration, etc. since the host adapter obviously
2592 * lost, and tell an interrupted NCR5380_select() to restart.
2595 NCR5380_write(MODE_REG, MR_BASE);
2597 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2599 dprintk(NDEBUG_RESELECTION, "scsi%d: reselect\n", HOSTNO);
2602 * At this point, we have detected that our SCSI ID is on the bus,
2603 * SEL is true and BSY was false for at least one bus settle delay
2606 * We must assert BSY ourselves, until the target drops the SEL
2610 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2612 while (NCR5380_read(STATUS_REG) & SR_SEL)
2614 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2617 * Wait for target to go into MSGIN.
2620 while (!(NCR5380_read(STATUS_REG) & SR_REQ))
2623 #if defined(CONFIG_SUN3) && defined(REAL_DMA)
2624 /* acknowledge toggle to MSGIN */
2625 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN));
2627 /* peek at the byte without really hitting the bus */
2628 msg[0] = NCR5380_read(CURRENT_SCSI_DATA_REG);
2632 phase = PHASE_MSGIN;
2633 NCR5380_transfer_pio(instance, &phase, &len, &data);
2636 if (!(msg[0] & 0x80)) {
2637 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
2642 lun = (msg[0] & 0x07);
2644 #if defined(SUPPORT_TAGS) && !defined(CONFIG_SUN3)
2645 /* If the phase is still MSGIN, the target wants to send some more
2646 * messages. In case it supports tagged queuing, this is probably a
2647 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2650 if (phase == PHASE_MSGIN && (hostdata->flags & FLAG_TAGGED_QUEUING)) {
2651 /* Accept previous IDENTIFY message by clearing ACK */
2652 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2655 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2656 msg[1] == SIMPLE_QUEUE_TAG)
2658 dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at "
2659 "reselection\n", HOSTNO, target_mask, lun, tag);
2664 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2665 * just reestablished, and remove it from the disconnected queue.
2668 for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue, prev = NULL;
2669 tmp; prev = tmp, tmp = NEXT(tmp)) {
2670 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2672 && (tag == tmp->tag)
2676 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2677 SET_NEXT(prev, NEXT(tmp));
2679 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
2680 hostdata->disconnected_queue = NEXT(tmp);
2682 SET_NEXT(tmp, NULL);
2688 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
2692 "not in disconnected_queue.\n",
2693 HOSTNO, target_mask, lun
2699 * Since we have an established nexus that we can't do anything
2700 * with, we must abort it.
2706 #if defined(CONFIG_SUN3) && defined(REAL_DMA)
2707 /* engage dma setup for the command we just saw */
2710 unsigned long count;
2712 if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
2713 count = tmp->SCp.buffer->length;
2714 d = sg_virt(tmp->SCp.buffer);
2716 count = tmp->SCp.this_residual;
2719 /* setup this command for dma if not already */
2720 if ((count >= DMA_MIN_SIZE) && (sun3_dma_setup_done != tmp)) {
2721 sun3scsi_dma_setup(d, count, rq_data_dir(tmp->request));
2722 sun3_dma_setup_done = tmp;
2726 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
2729 /* Accept message by clearing ACK */
2730 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2732 #if defined(SUPPORT_TAGS) && defined(CONFIG_SUN3)
2733 /* If the phase is still MSGIN, the target wants to send some more
2734 * messages. In case it supports tagged queuing, this is probably a
2735 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2738 if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
2739 /* Accept previous IDENTIFY message by clearing ACK */
2740 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2743 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2744 msg[1] == SIMPLE_QUEUE_TAG)
2746 dprintk(NDEBUG_TAGS, "scsi%d: target mask %02x, lun %d sent tag %d at reselection\n"
2747 HOSTNO, target_mask, lun, tag);
2751 hostdata->connected = tmp;
2752 dprintk(NDEBUG_RESELECTION, "scsi%d: nexus established, target = %d, lun = %llu, tag = %d\n",
2753 HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
2758 * Function : int NCR5380_abort (struct scsi_cmnd *cmd)
2760 * Purpose : abort a command
2762 * Inputs : cmd - the scsi_cmnd to abort, code - code to set the
2763 * host byte of the result field to, if zero DID_ABORTED is
2766 * Returns : SUCCESS - success, FAILED on failure.
2768 * XXX - there is no way to abort the command that is currently
2769 * connected, you have to wait for it to complete. If this is
2770 * a problem, we could implement longjmp() / setjmp(), setjmp()
2771 * called where the loop started in NCR5380_main().
2775 int NCR5380_abort(struct scsi_cmnd *cmd)
2777 struct Scsi_Host *instance = cmd->device->host;
2778 SETUP_HOSTDATA(instance);
2779 struct scsi_cmnd *tmp, **prev;
2780 unsigned long flags;
2782 scmd_printk(KERN_NOTICE, cmd, "aborting command\n");
2784 NCR5380_print_status(instance);
2786 local_irq_save(flags);
2788 dprintk(NDEBUG_ABORT, "scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2789 NCR5380_read(BUS_AND_STATUS_REG),
2790 NCR5380_read(STATUS_REG));
2794 * Case 1 : If the command is the currently executing command,
2795 * we'll set the aborted flag and return control so that
2796 * information transfer routine can exit cleanly.
2799 if (hostdata->connected == cmd) {
2801 dprintk(NDEBUG_ABORT, "scsi%d: aborting connected command\n", HOSTNO);
2803 * We should perform BSY checking, and make sure we haven't slipped
2807 /* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2809 * Since we can't change phases until we've completed the current
2810 * handshake, we have to source or sink a byte of data if the current
2811 * phase is not MSGOUT.
2815 * Return control to the executing NCR drive so we can clear the
2816 * aborted flag and get back into our main loop.
2819 if (do_abort(instance) == 0) {
2820 hostdata->connected = NULL;
2821 cmd->result = DID_ABORT << 16;
2825 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2827 maybe_release_dma_irq(instance);
2828 local_irq_restore(flags);
2829 cmd->scsi_done(cmd);
2832 local_irq_restore(flags);
2833 printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2840 * Case 2 : If the command hasn't been issued yet, we simply remove it
2841 * from the issue queue.
2843 for (prev = (struct scsi_cmnd **)&(hostdata->issue_queue),
2844 tmp = (struct scsi_cmnd *)hostdata->issue_queue;
2845 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
2847 REMOVE(5, *prev, tmp, NEXT(tmp));
2848 (*prev) = NEXT(tmp);
2849 SET_NEXT(tmp, NULL);
2850 tmp->result = DID_ABORT << 16;
2851 maybe_release_dma_irq(instance);
2852 local_irq_restore(flags);
2853 dprintk(NDEBUG_ABORT, "scsi%d: abort removed command from issue queue.\n",
2855 /* Tagged queuing note: no tag to free here, hasn't been assigned
2857 tmp->scsi_done(tmp);
2863 * Case 3 : If any commands are connected, we're going to fail the abort
2864 * and let the high level SCSI driver retry at a later time or
2867 * Timeouts, and therefore aborted commands, will be highly unlikely
2868 * and handling them cleanly in this situation would make the common
2869 * case of noresets less efficient, and would pollute our code. So,
2873 if (hostdata->connected) {
2874 local_irq_restore(flags);
2875 dprintk(NDEBUG_ABORT, "scsi%d: abort failed, command connected.\n", HOSTNO);
2880 * Case 4: If the command is currently disconnected from the bus, and
2881 * there are no connected commands, we reconnect the I_T_L or
2882 * I_T_L_Q nexus associated with it, go into message out, and send
2885 * This case is especially ugly. In order to reestablish the nexus, we
2886 * need to call NCR5380_select(). The easiest way to implement this
2887 * function was to abort if the bus was busy, and let the interrupt
2888 * handler triggered on the SEL for reselect take care of lost arbitrations
2889 * where necessary, meaning interrupts need to be enabled.
2891 * When interrupts are enabled, the queues may change - so we
2892 * can't remove it from the disconnected queue before selecting it
2893 * because that could cause a failure in hashing the nexus if that
2894 * device reselected.
2896 * Since the queues may change, we can't use the pointers from when we
2899 * So, we must first locate the command, and if NCR5380_select()
2900 * succeeds, then issue the abort, relocate the command and remove
2901 * it from the disconnected queue.
2904 for (tmp = (struct scsi_cmnd *) hostdata->disconnected_queue; tmp;
2907 local_irq_restore(flags);
2908 dprintk(NDEBUG_ABORT, "scsi%d: aborting disconnected command.\n", HOSTNO);
2910 if (NCR5380_select(instance, cmd))
2913 dprintk(NDEBUG_ABORT, "scsi%d: nexus reestablished.\n", HOSTNO);
2917 local_irq_save(flags);
2918 for (prev = (struct scsi_cmnd **)&(hostdata->disconnected_queue),
2919 tmp = (struct scsi_cmnd *)hostdata->disconnected_queue;
2920 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
2922 REMOVE(5, *prev, tmp, NEXT(tmp));
2924 SET_NEXT(tmp, NULL);
2925 tmp->result = DID_ABORT << 16;
2926 /* We must unlock the tag/LUN immediately here, since the
2927 * target goes to BUS FREE and doesn't send us another
2928 * message (COMMAND_COMPLETE or the like)
2933 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2935 maybe_release_dma_irq(instance);
2936 local_irq_restore(flags);
2937 tmp->scsi_done(tmp);
2944 /* Maybe it is sufficient just to release the ST-DMA lock... (if
2945 * possible at all) At least, we should check if the lock could be
2946 * released after the abort, in case it is kept due to some bug.
2948 maybe_release_dma_irq(instance);
2949 local_irq_restore(flags);
2952 * Case 5 : If we reached this point, the command was not found in any of
2955 * We probably reached this point because of an unlikely race condition
2956 * between the command completing successfully and the abortion code,
2957 * so we won't panic, but we will notify the user in case something really
2961 printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO);
2968 * NCR5380_bus_reset - reset the SCSI bus
2969 * @cmd: SCSI command undergoing EH
2974 static int NCR5380_bus_reset(struct scsi_cmnd *cmd)
2976 struct Scsi_Host *instance = cmd->device->host;
2977 struct NCR5380_hostdata *hostdata = shost_priv(instance);
2979 unsigned long flags;
2981 local_irq_save(flags);
2983 #if (NDEBUG & NDEBUG_ANY)
2984 scmd_printk(KERN_INFO, cmd, "performing bus reset\n");
2985 NCR5380_print_status(instance);
2990 /* reset NCR registers */
2991 NCR5380_write(MODE_REG, MR_BASE);
2992 NCR5380_write(TARGET_COMMAND_REG, 0);
2993 NCR5380_write(SELECT_ENABLE_REG, 0);
2995 /* After the reset, there are no more connected or disconnected commands
2996 * and no busy units; so clear the low-level status here to avoid
2997 * conflicts when the mid-level code tries to wake up the affected
3001 if (hostdata->issue_queue)
3002 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
3003 if (hostdata->connected)
3004 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted a connected command\n", H_NO(cmd));
3005 if (hostdata->disconnected_queue)
3006 dprintk(NDEBUG_ABORT, "scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
3008 hostdata->issue_queue = NULL;
3009 hostdata->connected = NULL;
3010 hostdata->disconnected_queue = NULL;
3012 free_all_tags(hostdata);
3014 for (i = 0; i < 8; ++i)
3015 hostdata->busy[i] = 0;
3017 hostdata->dma_len = 0;
3020 maybe_release_dma_irq(instance);
3021 local_irq_restore(flags);