1 /* sun3_NCR5380.c -- adapted from atari_NCR5380.c for the sun3 by
4 * NCR 5380 generic driver routines. These should make it *trivial*
5 * to implement 5380 SCSI drivers under Linux with a non-trantor
8 * Note that these routines also work with NR53c400 family chips.
10 * Copyright 1993, Drew Eckhardt
12 * (Unix and Linux consulting and custom programming)
16 * DISTRIBUTION RELEASE 6.
18 * For more information, please consult
21 * SCSI Protocol Controller
24 * NCR Microelectronics
25 * 1635 Aeroplaza Drive
26 * Colorado Springs, CO 80916
32 * ++roman: To port the 5380 driver to the Atari, I had to do some changes in
35 * - Some of the debug statements were incorrect (undefined variables and the
36 * like). I fixed that.
38 * - In information_transfer(), I think a #ifdef was wrong. Looking at the
39 * possible DMA transfer size should also happen for REAL_DMA. I added this
40 * in the #if statement.
42 * - When using real DMA, information_transfer() should return in a DATAOUT
43 * phase after starting the DMA. It has nothing more to do.
45 * - The interrupt service routine should run main after end of DMA, too (not
46 * only after RESELECTION interrupts). Additionally, it should _not_ test
47 * for more interrupts after running main, since a DMA process may have
48 * been started and interrupts are turned on now. The new int could happen
49 * inside the execution of NCR5380_intr(), leading to recursive
52 * - I've added a function merge_contiguous_buffers() that tries to
53 * merge scatter-gather buffers that are located at contiguous
54 * physical addresses and can be processed with the same DMA setup.
55 * Since most scatter-gather operations work on a page (4K) of
56 * 4 buffers (1K), in more than 90% of all cases three interrupts and
57 * DMA setup actions are saved.
59 * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA
60 * and USLEEP, because these were messing up readability and will never be
61 * needed for Atari SCSI.
63 * - I've revised the NCR5380_main() calling scheme (relax the 'main_running'
64 * stuff), and 'main' is executed in a bottom half if awoken by an
67 * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..."
68 * constructs. In my eyes, this made the source rather unreadable, so I
69 * finally replaced that by the *_PRINTK() macros.
74 * Further development / testing that should be done :
75 * 1. Test linked command handling code after Eric is ready with
76 * the high level code.
79 #if (NDEBUG & NDEBUG_LISTS)
81 { printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); \
82 if ((x)==(y)) udelay(5); }
83 #define REMOVE(w,x,y,z) \
84 { printk("LINE:%d Removing: %p->%p %p->%p \n", __LINE__, \
85 (void*)(w), (void*)(x), (void*)(y), (void*)(z)); \
86 if ((x)==(y)) udelay(5); }
89 #define REMOVE(w,x,y,z)
100 * The other Linux SCSI drivers were written when Linux was Intel PC-only,
101 * and specifically for each board rather than each chip. This makes their
102 * adaptation to platforms like the Mac (Some of which use NCR5380's)
103 * more difficult than it has to be.
105 * Also, many of the SCSI drivers were written before the command queuing
106 * routines were implemented, meaning their implementations of queued
107 * commands were hacked on rather than designed in from the start.
109 * When I designed the Linux SCSI drivers I figured that
110 * while having two different SCSI boards in a system might be useful
111 * for debugging things, two of the same type wouldn't be used.
112 * Well, I was wrong and a number of users have mailed me about running
113 * multiple high-performance SCSI boards in a server.
115 * Finally, when I get questions from users, I have no idea what
116 * revision of my driver they are running.
118 * This driver attempts to address these problems :
119 * This is a generic 5380 driver. To use it on a different platform,
120 * one simply writes appropriate system specific macros (ie, data
121 * transfer - some PC's will use the I/O bus, 68K's must use
122 * memory mapped) and drops this file in their 'C' wrapper.
124 * As far as command queueing, two queues are maintained for
125 * each 5380 in the system - commands that haven't been issued yet,
126 * and commands that are currently executing. This means that an
127 * unlimited number of commands may be queued, letting
128 * more commands propagate from the higher driver levels giving higher
129 * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported,
130 * allowing multiple commands to propagate all the way to a SCSI-II device
131 * while a command is already executing.
133 * To solve the multiple-boards-in-the-same-system problem,
134 * there is a separate instance structure for each instance
135 * of a 5380 in the system. So, multiple NCR5380 drivers will
136 * be able to coexist with appropriate changes to the high level
139 * A NCR5380_PUBLIC_REVISION macro is provided, with the release
140 * number (updated for each public release) printed by the
141 * NCR5380_print_options command, which should be called from the
142 * wrapper detect function, so that I know what release of the driver
145 * Issues specific to the NCR5380 :
147 * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
148 * piece of hardware that requires you to sit in a loop polling for
149 * the REQ signal as long as you are connected. Some devices are
150 * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
151 * while doing long seek operations.
153 * The workaround for this is to keep track of devices that have
154 * disconnected. If the device hasn't disconnected, for commands that
155 * should disconnect, we do something like
157 * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
159 * Some tweaking of N and M needs to be done. An algorithm based
160 * on "time to data" would give the best results as long as short time
161 * to datas (ie, on the same track) were considered, however these
162 * broken devices are the exception rather than the rule and I'd rather
163 * spend my time optimizing for the normal case.
167 * At the heart of the design is a coroutine, NCR5380_main,
168 * which is started when not running by the interrupt handler,
169 * timer, and queue command function. It attempts to establish
170 * I_T_L or I_T_L_Q nexuses by removing the commands from the
171 * issue queue and calling NCR5380_select() if a nexus
172 * is not established.
174 * Once a nexus is established, the NCR5380_information_transfer()
175 * phase goes through the various phases as instructed by the target.
176 * if the target goes into MSG IN and sends a DISCONNECT message,
177 * the command structure is placed into the per instance disconnected
178 * queue, and NCR5380_main tries to find more work. If USLEEP
179 * was defined, and the target is idle for too long, the system
182 * If a command has disconnected, eventually an interrupt will trigger,
183 * calling NCR5380_intr() which will in turn call NCR5380_reselect
184 * to reestablish a nexus. This will run main if necessary.
186 * On command termination, the done function will be called as
189 * SCSI pointers are maintained in the SCp field of SCSI command
190 * structures, being initialized after the command is connected
191 * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
192 * Note that in violation of the standard, an implicit SAVE POINTERS operation
193 * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
198 * This file a skeleton Linux SCSI driver for the NCR 5380 series
199 * of chips. To use it, you write an architecture specific functions
200 * and macros and include this file in your driver.
202 * These macros control options :
203 * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
204 * for commands that return with a CHECK CONDITION status.
206 * LINKED - if defined, linked commands are supported.
208 * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
210 * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
212 * These macros MUST be defined :
214 * NCR5380_read(register) - read from the specified register
216 * NCR5380_write(register, value) - write to the specific register
218 * Either real DMA *or* pseudo DMA may be implemented
220 * NCR5380_REAL_DMA should be defined if real DMA is to be used.
221 * Note that the DMA setup functions should return the number of bytes
222 * that they were able to program the controller for.
224 * Also note that generic i386/PC versions of these macros are
225 * available as NCR5380_i386_dma_write_setup,
226 * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
228 * NCR5380_dma_write_setup(instance, src, count) - initialize
229 * NCR5380_dma_read_setup(instance, dst, count) - initialize
230 * NCR5380_dma_residual(instance); - residual count
233 * NCR5380_pwrite(instance, src, count)
234 * NCR5380_pread(instance, dst, count);
236 * If nothing specific to this implementation needs doing (ie, with external
237 * hardware), you must also define
239 * NCR5380_queue_command
244 * to be the global entry points into the specific driver, ie
245 * #define NCR5380_queue_command t128_queue_command.
247 * If this is not done, the routines will be defined as static functions
248 * with the NCR5380* names and the user must provide a globally
249 * accessible wrapper function.
251 * The generic driver is initialized by calling NCR5380_init(instance),
252 * after setting the appropriate host specific fields and ID. If the
253 * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
254 * possible) function may be used. Before the specific driver initialization
255 * code finishes, NCR5380_print_options should be called.
258 static struct Scsi_Host *first_instance = NULL;
259 static Scsi_Host_Template *the_template = NULL;
261 /* Macros ease life... :-) */
262 #define SETUP_HOSTDATA(in) \
263 struct NCR5380_hostdata *hostdata = \
264 (struct NCR5380_hostdata *)(in)->hostdata
265 #define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)
267 #define NEXT(cmd) ((Scsi_Cmnd *)((cmd)->host_scribble))
268 #define NEXTADDR(cmd) ((Scsi_Cmnd **)&((cmd)->host_scribble))
270 #define HOSTNO instance->host_no
271 #define H_NO(cmd) (cmd)->host->host_no
276 * Functions for handling tagged queuing
277 * =====================================
279 * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
281 * Using consecutive numbers for the tags is no good idea in my eyes. There
282 * could be wrong re-usings if the counter (8 bit!) wraps and some early
283 * command has been preempted for a long time. My solution: a bitfield for
284 * remembering used tags.
286 * There's also the problem that each target has a certain queue size, but we
287 * cannot know it in advance :-( We just see a QUEUE_FULL status being
288 * returned. So, in this case, the driver internal queue size assumption is
289 * reduced to the number of active tags if QUEUE_FULL is returned by the
290 * target. The command is returned to the mid-level, but with status changed
291 * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL
294 * We're also not allowed running tagged commands as long as an untagged
295 * command is active. And REQUEST SENSE commands after a contingent allegiance
296 * condition _must_ be untagged. To keep track whether an untagged command has
297 * been issued, the host->busy array is still employed, as it is without
298 * support for tagged queuing.
300 * One could suspect that there are possible race conditions between
301 * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
302 * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
303 * which already guaranteed to be running at most once. It is also the only
304 * place where tags/LUNs are allocated. So no other allocation can slip
305 * between that pair, there could only happen a reselection, which can free a
306 * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
307 * important: the tag bit must be cleared before 'nr_allocated' is decreased.
310 /* -1 for TAG_NONE is not possible with unsigned char cmd->tag */
312 #define TAG_NONE 0xff
314 /* For the m68k, the number of bits in 'allocated' must be a multiple of 32! */
315 #if (MAX_TAGS % 32) != 0
316 #error "MAX_TAGS must be a multiple of 32!"
320 char allocated[MAX_TAGS/8];
325 static TAG_ALLOC TagAlloc[8][8]; /* 8 targets and 8 LUNs */
328 static void __init init_tags( void )
333 if (!setup_use_tagged_queuing)
336 for( target = 0; target < 8; ++target ) {
337 for( lun = 0; lun < 8; ++lun ) {
338 ta = &TagAlloc[target][lun];
339 memset( &ta->allocated, 0, MAX_TAGS/8 );
340 ta->nr_allocated = 0;
341 /* At the beginning, assume the maximum queue size we could
342 * support (MAX_TAGS). This value will be decreased if the target
343 * returns QUEUE_FULL status.
345 ta->queue_size = MAX_TAGS;
351 /* Check if we can issue a command to this LUN: First see if the LUN is marked
352 * busy by an untagged command. If the command should use tagged queuing, also
353 * check that there is a free tag and the target's queue won't overflow. This
354 * function should be called with interrupts disabled to avoid race
358 static int is_lun_busy( Scsi_Cmnd *cmd, int should_be_tagged )
360 SETUP_HOSTDATA(cmd->host);
362 if (hostdata->busy[cmd->target] & (1 << cmd->lun))
364 if (!should_be_tagged ||
365 !setup_use_tagged_queuing || !cmd->device->tagged_supported)
367 if (TagAlloc[cmd->target][cmd->lun].nr_allocated >=
368 TagAlloc[cmd->target][cmd->lun].queue_size ) {
369 TAG_PRINTK( "scsi%d: target %d lun %d: no free tags\n",
370 H_NO(cmd), cmd->target, cmd->lun );
377 /* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
378 * must be called before!), or reserve the LUN in 'busy' if the command is
382 static void cmd_get_tag( Scsi_Cmnd *cmd, int should_be_tagged )
384 SETUP_HOSTDATA(cmd->host);
386 /* If we or the target don't support tagged queuing, allocate the LUN for
387 * an untagged command.
389 if (!should_be_tagged ||
390 !setup_use_tagged_queuing || !cmd->device->tagged_supported) {
392 hostdata->busy[cmd->target] |= (1 << cmd->lun);
393 TAG_PRINTK( "scsi%d: target %d lun %d now allocated by untagged "
394 "command\n", H_NO(cmd), cmd->target, cmd->lun );
397 TAG_ALLOC *ta = &TagAlloc[cmd->target][cmd->lun];
399 cmd->tag = find_first_zero_bit( &ta->allocated, MAX_TAGS );
400 set_bit( cmd->tag, &ta->allocated );
402 TAG_PRINTK( "scsi%d: using tag %d for target %d lun %d "
403 "(now %d tags in use)\n",
404 H_NO(cmd), cmd->tag, cmd->target, cmd->lun,
410 /* Mark the tag of command 'cmd' as free, or in case of an untagged command,
414 static void cmd_free_tag( Scsi_Cmnd *cmd )
416 SETUP_HOSTDATA(cmd->host);
418 if (cmd->tag == TAG_NONE) {
419 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
420 TAG_PRINTK( "scsi%d: target %d lun %d untagged cmd finished\n",
421 H_NO(cmd), cmd->target, cmd->lun );
423 else if (cmd->tag >= MAX_TAGS) {
424 printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n",
425 H_NO(cmd), cmd->tag );
428 TAG_ALLOC *ta = &TagAlloc[cmd->target][cmd->lun];
429 clear_bit( cmd->tag, &ta->allocated );
431 TAG_PRINTK( "scsi%d: freed tag %d for target %d lun %d\n",
432 H_NO(cmd), cmd->tag, cmd->target, cmd->lun );
437 static void free_all_tags( void )
442 if (!setup_use_tagged_queuing)
445 for( target = 0; target < 8; ++target ) {
446 for( lun = 0; lun < 8; ++lun ) {
447 ta = &TagAlloc[target][lun];
448 memset( &ta->allocated, 0, MAX_TAGS/8 );
449 ta->nr_allocated = 0;
454 #endif /* SUPPORT_TAGS */
458 * Function: void merge_contiguous_buffers( Scsi_Cmnd *cmd )
460 * Purpose: Try to merge several scatter-gather requests into one DMA
461 * transfer. This is possible if the scatter buffers lie on
462 * physical contiguous addresses.
464 * Parameters: Scsi_Cmnd *cmd
465 * The command to work on. The first scatter buffer's data are
466 * assumed to be already transfered into ptr/this_residual.
469 static void merge_contiguous_buffers( Scsi_Cmnd *cmd )
471 unsigned long endaddr;
472 #if (NDEBUG & NDEBUG_MERGING)
473 unsigned long oldlen = cmd->SCp.this_residual;
477 for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
478 cmd->SCp.buffers_residual &&
479 virt_to_phys(cmd->SCp.buffer[1].address) == endaddr; ) {
481 MER_PRINTK("VTOP(%p) == %08lx -> merging\n",
482 cmd->SCp.buffer[1].address, 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 MER_PRINTK("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.
515 cmd->SCp.buffer = (struct scatterlist *) cmd->buffer;
516 cmd->SCp.buffers_residual = cmd->use_sg - 1;
517 cmd->SCp.ptr = (char *) cmd->SCp.buffer->address;
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;
526 cmd->SCp.ptr = (char *) cmd->request_buffer;
527 cmd->SCp.this_residual = cmd->request_bufflen;
532 #include <linux/config.h>
533 #include <linux/delay.h>
539 signals[] = {{ SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" },
540 { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" },
541 { SR_SEL, "SEL" }, {0, NULL}},
542 basrs[] = {{BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}},
543 icrs[] = {{ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"},
544 {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"},
545 {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"},
547 mrs[] = {{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"},
548 {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR,
549 "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"},
550 {MR_MONITOR_BSY, "MODE MONITOR BSY"},
551 {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"},
555 * Function : void NCR5380_print(struct Scsi_Host *instance)
557 * Purpose : print the SCSI bus signals for debugging purposes
559 * Input : instance - which NCR5380
562 static void NCR5380_print(struct Scsi_Host *instance) {
563 unsigned char status, data, basr, mr, icr, i;
568 data = NCR5380_read(CURRENT_SCSI_DATA_REG);
569 status = NCR5380_read(STATUS_REG);
570 mr = NCR5380_read(MODE_REG);
571 icr = NCR5380_read(INITIATOR_COMMAND_REG);
572 basr = NCR5380_read(BUS_AND_STATUS_REG);
573 restore_flags(flags);
574 printk("STATUS_REG: %02x ", status);
575 for (i = 0; signals[i].mask ; ++i)
576 if (status & signals[i].mask)
577 printk(",%s", signals[i].name);
578 printk("\nBASR: %02x ", basr);
579 for (i = 0; basrs[i].mask ; ++i)
580 if (basr & basrs[i].mask)
581 printk(",%s", basrs[i].name);
582 printk("\nICR: %02x ", icr);
583 for (i = 0; icrs[i].mask; ++i)
584 if (icr & icrs[i].mask)
585 printk(",%s", icrs[i].name);
586 printk("\nMODE: %02x ", mr);
587 for (i = 0; mrs[i].mask; ++i)
588 if (mr & mrs[i].mask)
589 printk(",%s", mrs[i].name);
597 {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
598 {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
599 {PHASE_UNKNOWN, "UNKNOWN"}};
602 * Function : void NCR5380_print_phase(struct Scsi_Host *instance)
604 * Purpose : print the current SCSI phase for debugging purposes
606 * Input : instance - which NCR5380
609 static void NCR5380_print_phase(struct Scsi_Host *instance)
611 unsigned char status;
614 status = NCR5380_read(STATUS_REG);
615 if (!(status & SR_REQ))
616 printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO);
618 for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
619 (phases[i].value != (status & PHASE_MASK)); ++i);
620 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name);
627 __inline__ void NCR5380_print(struct Scsi_Host *instance) { };
628 __inline__ void NCR5380_print_phase(struct Scsi_Host *instance) { };
633 * ++roman: New scheme of calling NCR5380_main()
635 * If we're not in an interrupt, we can call our main directly, it cannot be
636 * already running. Else, we queue it on a task queue, if not 'main_running'
637 * tells us that a lower level is already executing it. This way,
638 * 'main_running' needs not be protected in a special way.
640 * queue_main() is a utility function for putting our main onto the task
641 * queue, if main_running is false. It should be called only from a
642 * interrupt or bottom half.
645 #include <linux/tqueue.h>
646 #include <linux/interrupt.h>
648 static volatile int main_running = 0;
649 static struct tq_struct NCR5380_tqueue = {
650 routine: (void (*)(void*))NCR5380_main /* must have (void *) arg... */
653 static __inline__ void queue_main(void)
656 /* If in interrupt and NCR5380_main() not already running,
657 queue it on the 'immediate' task queue, to be processed
658 immediately after the current interrupt processing has
660 queue_task(&NCR5380_tqueue, &tq_immediate);
661 mark_bh(IMMEDIATE_BH);
663 /* else: nothing to do: the running NCR5380_main() will pick up
664 any newly queued command. */
668 static inline void NCR5380_all_init (void)
672 INI_PRINTK("scsi : NCR5380_all_init()\n");
679 * Function : void NCR58380_print_options (struct Scsi_Host *instance)
681 * Purpose : called by probe code indicating the NCR5380 driver
682 * options that were selected.
684 * Inputs : instance, pointer to this instance. Unused.
687 static void __init NCR5380_print_options (struct Scsi_Host *instance)
689 printk(" generic options"
700 " SCSI-2 TAGGED QUEUING"
703 printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
707 * Function : void NCR5380_print_status (struct Scsi_Host *instance)
709 * Purpose : print commands in the various queues, called from
710 * NCR5380_abort and NCR5380_debug to aid debugging.
712 * Inputs : instance, pointer to this instance.
715 static void NCR5380_print_status (struct Scsi_Host *instance)
721 NCR_PRINT(NDEBUG_ANY);
722 NCR_PRINT_PHASE(NDEBUG_ANY);
724 pr_bfr = (char *) __get_free_page(GFP_ATOMIC);
726 printk("NCR5380_print_status: no memory for print buffer\n");
729 len = NCR5380_proc_info(pr_bfr, &start, 0, PAGE_SIZE, HOSTNO, 0);
731 printk("\n%s\n", pr_bfr);
732 free_page((unsigned long) pr_bfr);
736 /******************************************/
738 * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
740 * *buffer: I/O buffer
741 * **start: if inout == FALSE pointer into buffer where user read should start
742 * offset: current offset
743 * length: length of buffer
744 * hostno: Scsi_Host host_no
745 * inout: TRUE - user is writing; FALSE - user is reading
747 * Return the number of bytes read from or written
751 #define SPRINTF(fmt,args...) \
752 do { if (pos + strlen(fmt) + 20 /* slop */ < buffer + length) \
753 pos += sprintf(pos, fmt , ## args); } while(0)
755 char *lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length);
757 static int NCR5380_proc_info (char *buffer, char **start, off_t offset,
758 int length, int hostno, int inout)
761 struct Scsi_Host *instance;
762 struct NCR5380_hostdata *hostdata;
766 #define check_offset() \
768 if (pos - buffer < offset - begin) { \
769 begin += pos - buffer; \
774 for (instance = first_instance; instance && HOSTNO != hostno;
775 instance = instance->next)
779 hostdata = (struct NCR5380_hostdata *)instance->hostdata;
781 if (inout) { /* Has data been written to the file ? */
782 return(-ENOSYS); /* Currently this is a no-op */
784 SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
788 SPRINTF("NCR5380: coroutine is%s running.\n", main_running ? "" : "n't");
790 if (!hostdata->connected)
791 SPRINTF("scsi%d: no currently connected command\n", HOSTNO);
793 pos = lprint_Scsi_Cmnd ((Scsi_Cmnd *) hostdata->connected,
794 pos, buffer, length);
795 SPRINTF("scsi%d: issue_queue\n", HOSTNO);
797 for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = NEXT(ptr)) {
798 pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
802 SPRINTF("scsi%d: disconnected_queue\n", HOSTNO);
804 for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr;
806 pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length);
810 restore_flags(flags);
811 *start = buffer + (offset - begin);
812 if (pos - buffer < offset - begin)
814 else if (pos - buffer - (offset - begin) < length)
815 return pos - buffer - (offset - begin);
820 lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length)
823 unsigned char *command;
824 SPRINTF("scsi%d: destination target %d, lun %d\n",
825 H_NO(cmd), cmd->target, cmd->lun);
826 SPRINTF(" command = ");
828 SPRINTF("%2d (0x%02x)", command[0], command[0]);
829 for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
830 SPRINTF(" %02x", command[i]);
837 * Function : void NCR5380_init (struct Scsi_Host *instance)
839 * Purpose : initializes *instance and corresponding 5380 chip.
841 * Inputs : instance - instantiation of the 5380 driver.
843 * Notes : I assume that the host, hostno, and id bits have been
844 * set correctly. I don't care about the irq and other fields.
848 static void __init NCR5380_init (struct Scsi_Host *instance, int flags)
851 SETUP_HOSTDATA(instance);
855 hostdata->aborted = 0;
856 hostdata->id_mask = 1 << instance->this_id;
857 hostdata->id_higher_mask = 0;
858 for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
859 if (i > hostdata->id_mask)
860 hostdata->id_higher_mask |= i;
861 for (i = 0; i < 8; ++i)
862 hostdata->busy[i] = 0;
866 #if defined (REAL_DMA)
867 hostdata->dma_len = 0;
869 hostdata->targets_present = 0;
870 hostdata->connected = NULL;
871 hostdata->issue_queue = NULL;
872 hostdata->disconnected_queue = NULL;
873 hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT;
876 the_template = instance->hostt;
877 first_instance = instance;
882 if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1))
883 printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n"
884 " without AUTOSENSE option, contingent allegiance conditions may\n"
885 " be incorrectly cleared.\n", HOSTNO);
886 #endif /* def AUTOSENSE */
888 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
889 NCR5380_write(MODE_REG, MR_BASE);
890 NCR5380_write(TARGET_COMMAND_REG, 0);
891 NCR5380_write(SELECT_ENABLE_REG, 0);
895 * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd,
896 * void (*done)(Scsi_Cmnd *))
898 * Purpose : enqueues a SCSI command
900 * Inputs : cmd - SCSI command, done - function called on completion, with
901 * a pointer to the command descriptor.
906 * cmd is added to the per instance issue_queue, with minor
907 * twiddling done to the host specific fields of cmd. If the
908 * main coroutine is not running, it is restarted.
912 /* Only make static if a wrapper function is used */
913 static int NCR5380_queue_command (Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
915 SETUP_HOSTDATA(cmd->host);
918 extern int update_timeout(Scsi_Cmnd * SCset, int timeout);
920 #if (NDEBUG & NDEBUG_NO_WRITE)
921 switch (cmd->cmnd[0]) {
924 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
926 cmd->result = (DID_ERROR << 16);
930 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
935 if (!hostdata->connected && !hostdata->issue_queue &&
936 !hostdata->disconnected_queue) {
937 hostdata->timebase = jiffies;
940 # ifdef NCR5380_STAT_LIMIT
941 if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
943 switch (cmd->cmnd[0])
948 hostdata->time_write[cmd->target] -= (jiffies - hostdata->timebase);
949 hostdata->bytes_write[cmd->target] += cmd->request_bufflen;
950 hostdata->pendingw++;
955 hostdata->time_read[cmd->target] -= (jiffies - hostdata->timebase);
956 hostdata->bytes_read[cmd->target] += cmd->request_bufflen;
957 hostdata->pendingr++;
963 * We use the host_scribble field as a pointer to the next command
968 cmd->scsi_done = done;
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.
982 /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
983 * Otherwise a running NCR5380_main may steal the lock.
984 * Lock before actually inserting due to fairness reasons explained in
985 * atari_scsi.c. If we insert first, then it's impossible for this driver
986 * to release the lock.
987 * Stop timer for this command while waiting for the lock, or timeouts
988 * may happen (and they really do), and it's no good if the command doesn't
989 * appear in any of the queues.
990 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
991 * because also a timer int can trigger an abort or reset, which would
992 * alter queues and touch the lock.
994 if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
995 LIST(cmd, hostdata->issue_queue);
996 NEXT(cmd) = hostdata->issue_queue;
997 hostdata->issue_queue = cmd;
999 for (tmp = (Scsi_Cmnd *)hostdata->issue_queue;
1000 NEXT(tmp); tmp = NEXT(tmp))
1006 restore_flags(flags);
1008 QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd),
1009 (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
1011 /* If queue_command() is called from an interrupt (real one or bottom
1012 * half), we let queue_main() do the job of taking care about main. If it
1013 * is already running, this is a no-op, else main will be queued.
1015 * If we're not in an interrupt, we can call NCR5380_main()
1016 * unconditionally, because it cannot be already running.
1018 if (in_interrupt() || ((flags >> 8) & 7) >= 6)
1026 * Function : NCR5380_main (void)
1028 * Purpose : NCR5380_main is a coroutine that runs as long as more work can
1029 * be done on the NCR5380 host adapters in a system. Both
1030 * NCR5380_queue_command() and NCR5380_intr() will try to start it
1031 * in case it is not running.
1033 * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
1034 * reenable them. This prevents reentrancy and kernel stack overflow.
1037 static void NCR5380_main (void)
1039 Scsi_Cmnd *tmp, *prev;
1040 struct Scsi_Host *instance = first_instance;
1041 struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
1043 unsigned long flags;
1046 * We run (with interrupts disabled) until we're sure that none of
1047 * the host adapters have anything that can be done, at which point
1048 * we set main_running to 0 and exit.
1050 * Interrupts are enabled before doing various other internal
1051 * instructions, after we've decided that we need to run through
1054 * this should prevent any race conditions.
1056 * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1057 * because also a timer int can trigger an abort or reset, which can
1058 * alter queues and touch the Falcon lock.
1061 /* Tell int handlers main() is now already executing. Note that
1062 no races are possible here. If an int comes in before
1063 'main_running' is set here, and queues/executes main via the
1064 task queue, it doesn't do any harm, just this instance of main
1065 won't find any work left to do. */
1072 cli(); /* Freeze request queues */
1075 if (!hostdata->connected) {
1076 MAIN_PRINTK( "scsi%d: not connected\n", HOSTNO );
1078 * Search through the issue_queue for a command destined
1079 * for a target that's not busy.
1081 #if (NDEBUG & NDEBUG_LISTS)
1082 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL;
1083 tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
1085 if ((tmp == prev) && tmp) printk(" LOOP\n");/* else printk("\n");*/
1087 for (tmp = (Scsi_Cmnd *) hostdata->issue_queue,
1088 prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp) ) {
1090 #if (NDEBUG & NDEBUG_LISTS)
1092 printk("MAIN tmp=%p target=%d busy=%d lun=%d\n",
1093 tmp, tmp->target, hostdata->busy[tmp->target],
1096 /* When we find one, remove it from the issue queue. */
1097 /* ++guenther: possible race with Falcon locking */
1100 !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
1102 !(hostdata->busy[tmp->target] & (1 << tmp->lun))
1105 cli(); /* ++guenther: just to be sure, this must be atomic */
1107 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1108 NEXT(prev) = NEXT(tmp);
1110 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
1111 hostdata->issue_queue = NEXT(tmp);
1115 /* reenable interrupts after finding one */
1116 restore_flags(flags);
1119 * Attempt to establish an I_T_L nexus here.
1120 * On success, instance->hostdata->connected is set.
1121 * On failure, we must add the command back to the
1122 * issue queue so we can keep trying.
1124 MAIN_PRINTK("scsi%d: main(): command for target %d "
1125 "lun %d removed from issue_queue\n",
1126 HOSTNO, tmp->target, tmp->lun);
1128 * REQUEST SENSE commands are issued without tagged
1129 * queueing, even on SCSI-II devices because the
1130 * contingent allegiance condition exists for the
1133 /* ++roman: ...and the standard also requires that
1134 * REQUEST SENSE command are untagged.
1138 cmd_get_tag( tmp, tmp->cmnd[0] != REQUEST_SENSE );
1140 if (!NCR5380_select(instance, tmp,
1141 (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE :
1146 LIST(tmp, hostdata->issue_queue);
1147 NEXT(tmp) = hostdata->issue_queue;
1148 hostdata->issue_queue = tmp;
1150 cmd_free_tag( tmp );
1152 restore_flags(flags);
1153 MAIN_PRINTK("scsi%d: main(): select() failed, "
1154 "returned to issue_queue\n", HOSTNO);
1155 if (hostdata->connected)
1158 } /* if target/lun/target queue is not busy */
1159 } /* for issue_queue */
1160 } /* if (!hostdata->connected) */
1161 if (hostdata->connected
1163 && !hostdata->dma_len
1166 restore_flags(flags);
1167 MAIN_PRINTK("scsi%d: main: performing information transfer\n",
1169 NCR5380_information_transfer(instance);
1170 MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO);
1175 /* Better allow ints _after_ 'main_running' has been cleared, else
1176 an interrupt could believe we'll pick up the work it left for
1177 us, but we won't see it anymore here... */
1179 restore_flags(flags);
1185 * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1187 * Purpose : Called by interrupt handler when DMA finishes or a phase
1188 * mismatch occurs (which would finish the DMA transfer).
1190 * Inputs : instance - this instance of the NCR5380.
1194 static void NCR5380_dma_complete( struct Scsi_Host *instance )
1196 SETUP_HOSTDATA(instance);
1198 unsigned char **data;
1199 volatile int *count;
1201 if (!hostdata->connected) {
1202 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
1203 "no connected cmd\n", HOSTNO);
1207 DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1208 HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
1209 NCR5380_read(STATUS_REG));
1211 if((sun3scsi_dma_finish(hostdata->connected->request.cmd))) {
1212 printk("scsi%d: overrun in UDC counter -- not prepared to deal with this!\n", HOSTNO);
1213 printk("please e-mail sammy@sammy.net with a description of how this\n");
1214 printk("error was produced.\n");
1218 /* make sure we're not stuck in a data phase */
1219 if((NCR5380_read(BUS_AND_STATUS_REG) & (BASR_PHASE_MATCH |
1221 (BASR_PHASE_MATCH | BASR_ACK)) {
1222 printk("scsi%d: BASR %02x\n", HOSTNO, NCR5380_read(BUS_AND_STATUS_REG));
1223 printk("scsi%d: bus stuck in data phase -- probably a single byte "
1224 "overrun!\n", HOSTNO);
1225 printk("not prepared for this error!\n");
1226 printk("please e-mail sammy@sammy.net with a description of how this\n");
1227 printk("error was produced.\n");
1233 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1234 NCR5380_write(MODE_REG, MR_BASE);
1235 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1237 transfered = hostdata->dma_len - NCR5380_dma_residual(instance);
1238 hostdata->dma_len = 0;
1240 data = (unsigned char **) &(hostdata->connected->SCp.ptr);
1241 count = &(hostdata->connected->SCp.this_residual);
1242 *data += transfered;
1243 *count -= transfered;
1246 #endif /* REAL_DMA */
1250 * Function : void NCR5380_intr (int irq)
1252 * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1253 * from the disconnected queue, and restarting NCR5380_main()
1256 * Inputs : int irq, irq that caused this interrupt.
1260 static void NCR5380_intr (int irq, void *dev_id, struct pt_regs *regs)
1262 struct Scsi_Host *instance = first_instance;
1266 INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO);
1268 /* Look for pending interrupts */
1269 basr = NCR5380_read(BUS_AND_STATUS_REG);
1270 INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr);
1271 /* dispatch to appropriate routine if found and done=0 */
1272 if (basr & BASR_IRQ) {
1273 NCR_PRINT(NDEBUG_INTR);
1274 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
1277 INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO);
1278 NCR5380_reselect(instance);
1279 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1281 else if (basr & BASR_PARITY_ERROR) {
1282 INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO);
1283 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1285 else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1286 INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO);
1287 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1291 * The rest of the interrupt conditions can occur only during a
1295 #if defined(REAL_DMA)
1297 * We should only get PHASE MISMATCH and EOP interrupts if we have
1298 * DMA enabled, so do a sanity check based on the current setting
1299 * of the MODE register.
1302 if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
1303 ((basr & BASR_END_DMA_TRANSFER) ||
1304 !(basr & BASR_PHASE_MATCH))) {
1306 INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1307 NCR5380_dma_complete( instance );
1311 #endif /* REAL_DMA */
1313 /* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1314 if (basr & BASR_PHASE_MATCH)
1315 INT_PRINTK("scsi%d: unknown interrupt, "
1316 "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1317 HOSTNO, basr, NCR5380_read(MODE_REG),
1318 NCR5380_read(STATUS_REG));
1319 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1320 #ifdef SUN3_SCSI_VME
1321 dregs->csr |= CSR_DMA_ENABLE;
1324 } /* if !(SELECTION || PARITY) */
1328 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
1329 "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
1330 NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG));
1331 (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1332 #ifdef SUN3_SCSI_VME
1333 dregs->csr |= CSR_DMA_ENABLE;
1338 INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO);
1339 /* Put a call to NCR5380_main() on the queue... */
1344 #ifdef NCR5380_STATS
1345 static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd* cmd)
1347 # ifdef NCR5380_STAT_LIMIT
1348 if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
1350 switch (cmd->cmnd[0])
1355 hostdata->time_write[cmd->target] += (jiffies - hostdata->timebase);
1356 /*hostdata->bytes_write[cmd->target] += cmd->request_bufflen;*/
1357 hostdata->pendingw--;
1362 hostdata->time_read[cmd->target] += (jiffies - hostdata->timebase);
1363 /*hostdata->bytes_read[cmd->target] += cmd->request_bufflen;*/
1364 hostdata->pendingr--;
1371 * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1374 * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1375 * including ARBITRATION, SELECTION, and initial message out for
1376 * IDENTIFY and queue messages.
1378 * Inputs : instance - instantiation of the 5380 driver on which this
1379 * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1380 * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1381 * the command that is presently connected.
1383 * Returns : -1 if selection could not execute for some reason,
1384 * 0 if selection succeeded or failed because the target
1388 * If bus busy, arbitration failed, etc, NCR5380_select() will exit
1389 * with registers as they should have been on entry - ie
1390 * SELECT_ENABLE will be set appropriately, the NCR5380
1391 * will cease to drive any SCSI bus signals.
1393 * If successful : I_T_L or I_T_L_Q nexus will be established,
1394 * instance->connected will be set to cmd.
1395 * SELECT interrupt will be disabled.
1397 * If failed (no target) : cmd->scsi_done() will be called, and the
1398 * cmd->result host byte set to DID_BAD_TARGET.
1401 static int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag)
1403 SETUP_HOSTDATA(instance);
1404 unsigned char tmp[3], phase;
1405 unsigned char *data;
1407 unsigned long timeout;
1408 unsigned long flags;
1410 hostdata->restart_select = 0;
1411 NCR_PRINT(NDEBUG_ARBITRATION);
1412 ARB_PRINTK("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.
1422 if (hostdata->connected) {
1423 restore_flags(flags);
1426 NCR5380_write(TARGET_COMMAND_REG, 0);
1430 * Start arbitration.
1433 NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1434 NCR5380_write(MODE_REG, MR_ARBITRATE);
1436 restore_flags(flags);
1438 /* Wait for arbitration logic to complete */
1441 unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
1443 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)
1444 && time_before(jiffies, timeout) && !hostdata->connected)
1446 if (time_after_eq(jiffies, timeout))
1448 printk("scsi : arbitration timeout at %d\n", __LINE__);
1449 NCR5380_write(MODE_REG, MR_BASE);
1450 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1454 #else /* NCR_TIMEOUT */
1455 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS)
1456 && !hostdata->connected);
1459 ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO);
1461 if (hostdata->connected) {
1462 NCR5380_write(MODE_REG, MR_BASE);
1466 * The arbitration delay is 2.2us, but this is a minimum and there is
1467 * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1468 * the integral nature of udelay().
1474 /* Check for lost arbitration */
1475 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1476 (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
1477 (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1478 hostdata->connected) {
1479 NCR5380_write(MODE_REG, MR_BASE);
1480 ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1485 /* after/during arbitration, BSY should be asserted.
1486 IBM DPES-31080 Version S31Q works now */
1487 /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
1488 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL |
1491 if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1492 hostdata->connected) {
1493 NCR5380_write(MODE_REG, MR_BASE);
1494 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1495 ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1501 * Again, bus clear + bus settle time is 1.2us, however, this is
1502 * a minimum so we'll udelay ceil(1.2)
1505 #ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1506 /* ++roman: But some targets (see above :-) seem to need a bit more... */
1512 if (hostdata->connected) {
1513 NCR5380_write(MODE_REG, MR_BASE);
1514 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1518 ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO);
1521 * Now that we have won arbitration, start Selection process, asserting
1522 * the host and target ID's on the SCSI bus.
1525 NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->target)));
1528 * Raise ATN while SEL is true before BSY goes false from arbitration,
1529 * since this is the only way to guarantee that we'll get a MESSAGE OUT
1530 * phase immediately after selection.
1533 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY |
1534 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL ));
1535 NCR5380_write(MODE_REG, MR_BASE);
1538 * Reselect interrupts must be turned off prior to the dropping of BSY,
1539 * otherwise we will trigger an interrupt.
1542 if (hostdata->connected) {
1543 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1547 NCR5380_write(SELECT_ENABLE_REG, 0);
1550 * The initiator shall then wait at least two deskew delays and release
1553 udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */
1556 NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA |
1557 ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1560 * Something weird happens when we cease to drive BSY - looks
1561 * like the board/chip is letting us do another read before the
1562 * appropriate propagation delay has expired, and we're confusing
1563 * a BSY signal from ourselves as the target's response to SELECTION.
1565 * A small delay (the 'C++' frontend breaks the pipeline with an
1566 * unnecessary jump, making it work on my 386-33/Trantor T128, the
1567 * tighter 'C' code breaks and requires this) solves the problem -
1568 * the 1 us delay is arbitrary, and only used because this delay will
1569 * be the same on other platforms and since it works here, it should
1572 * wingel suggests that this could be due to failing to wait
1578 SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->target);
1581 * The SCSI specification calls for a 250 ms timeout for the actual
1585 timeout = jiffies + 25;
1588 * XXX very interesting - we're seeing a bounce where the BSY we
1589 * asserted is being reflected / still asserted (propagation delay?)
1590 * and it's detecting as true. Sigh.
1594 /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1595 * IO while SEL is true. But again, there are some disks out the in the
1596 * world that do that nevertheless. (Somebody claimed that this announces
1597 * reselection capability of the target.) So we better skip that test and
1598 * only wait for BSY... (Famous german words: Der Klügere gibt nach :-)
1601 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) &
1604 if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) ==
1606 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1607 NCR5380_reselect(instance);
1608 printk (KERN_ERR "scsi%d: reselection after won arbitration?\n",
1610 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1614 while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY));
1618 * No less than two deskew delays after the initiator detects the
1619 * BSY signal is true, it shall release the SEL signal and may
1620 * change the DATA BUS. -wingel
1625 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1627 if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1628 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1629 if (hostdata->targets_present & (1 << cmd->target)) {
1630 printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO);
1631 if (hostdata->restart_select)
1632 printk(KERN_NOTICE "\trestart select\n");
1633 NCR_PRINT(NDEBUG_ANY);
1634 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1637 cmd->result = DID_BAD_TARGET << 16;
1638 #ifdef NCR5380_STATS
1639 collect_stats(hostdata, cmd);
1642 cmd_free_tag( cmd );
1644 cmd->scsi_done(cmd);
1645 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1646 SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO);
1647 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1651 hostdata->targets_present |= (1 << cmd->target);
1654 * Since we followed the SCSI spec, and raised ATN while SEL
1655 * was true but before BSY was false during selection, the information
1656 * transfer phase should be a MESSAGE OUT phase so that we can send the
1659 * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1660 * message (2 bytes) with a tag ID that we increment with every command
1661 * until it wraps back to 0.
1663 * XXX - it turns out that there are some broken SCSI-II devices,
1664 * which claim to support tagged queuing but fail when more than
1665 * some number of commands are issued at once.
1668 /* Wait for start of REQ/ACK handshake */
1669 while (!(NCR5380_read(STATUS_REG) & SR_REQ));
1671 SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1672 HOSTNO, cmd->target);
1673 tmp[0] = IDENTIFY(1, cmd->lun);
1676 if (cmd->tag != TAG_NONE) {
1677 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
1685 #endif /* SUPPORT_TAGS */
1687 /* Send message(s) */
1689 phase = PHASE_MSGOUT;
1690 NCR5380_transfer_pio(instance, &phase, &len, &data);
1691 SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO);
1692 /* XXX need to handle errors here */
1693 hostdata->connected = cmd;
1694 #ifndef SUPPORT_TAGS
1695 hostdata->busy[cmd->target] |= (1 << cmd->lun);
1697 #ifdef SUN3_SCSI_VME
1698 dregs->csr |= CSR_INTR;
1700 initialize_SCp(cmd);
1707 * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1708 * unsigned char *phase, int *count, unsigned char **data)
1710 * Purpose : transfers data in given phase using polled I/O
1712 * Inputs : instance - instance of driver, *phase - pointer to
1713 * what phase is expected, *count - pointer to number of
1714 * bytes to transfer, **data - pointer to data pointer.
1716 * Returns : -1 when different phase is entered without transferring
1717 * maximum number of bytes, 0 if all bytes are transfered or exit
1720 * Also, *phase, *count, *data are modified in place.
1722 * XXX Note : handling for bus free may be useful.
1726 * Note : this code is not as quick as it could be, however it
1727 * IS 100% reliable, and for the actual data transfer where speed
1728 * counts, we will always do a pseudo DMA or DMA transfer.
1731 static int NCR5380_transfer_pio( struct Scsi_Host *instance,
1732 unsigned char *phase, int *count,
1733 unsigned char **data)
1735 register unsigned char p = *phase, tmp;
1736 register int c = *count;
1737 register unsigned char *d = *data;
1740 * The NCR5380 chip will only drive the SCSI bus when the
1741 * phase specified in the appropriate bits of the TARGET COMMAND
1742 * REGISTER match the STATUS REGISTER
1745 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1749 * Wait for assertion of REQ, after which the phase bits will be
1752 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ));
1754 HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO);
1756 /* Check for phase mismatch */
1757 if ((tmp & PHASE_MASK) != p) {
1758 PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO);
1759 NCR_PRINT_PHASE(NDEBUG_PIO);
1763 /* Do actual transfer from SCSI bus to / from memory */
1765 NCR5380_write(OUTPUT_DATA_REG, *d);
1767 *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1772 * The SCSI standard suggests that in MSGOUT phase, the initiator
1773 * should drop ATN on the last byte of the message phase
1774 * after REQ has been asserted for the handshake but before
1775 * the initiator raises ACK.
1779 if (!((p & SR_MSG) && c > 1)) {
1780 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1782 NCR_PRINT(NDEBUG_PIO);
1783 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1784 ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1786 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1787 ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1788 NCR_PRINT(NDEBUG_PIO);
1789 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1790 ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1793 NCR_PRINT(NDEBUG_PIO);
1794 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1797 while (NCR5380_read(STATUS_REG) & SR_REQ);
1799 HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO);
1802 * We have several special cases to consider during REQ/ACK handshaking :
1803 * 1. We were in MSGOUT phase, and we are on the last byte of the
1804 * message. ATN must be dropped as ACK is dropped.
1806 * 2. We are in a MSGIN phase, and we are on the last byte of the
1807 * message. We must exit with ACK asserted, so that the calling
1808 * code may raise ATN before dropping ACK to reject the message.
1810 * 3. ACK and ATN are clear and the target may proceed as normal.
1812 if (!(p == PHASE_MSGIN && c == 1)) {
1813 if (p == PHASE_MSGOUT && c > 1)
1814 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1816 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1820 PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c);
1824 tmp = NCR5380_read(STATUS_REG);
1825 /* The phase read from the bus is valid if either REQ is (already)
1826 * asserted or if ACK hasn't been released yet. The latter is the case if
1827 * we're in MSGIN and all wanted bytes have been received. */
1828 if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
1829 *phase = tmp & PHASE_MASK;
1831 *phase = PHASE_UNKNOWN;
1833 if (!c || (*phase == p))
1840 * Function : do_abort (Scsi_Host *host)
1842 * Purpose : abort the currently established nexus. Should only be
1843 * called from a routine which can drop into a
1845 * Returns : 0 on success, -1 on failure.
1848 static int do_abort (struct Scsi_Host *host)
1850 unsigned char tmp, *msgptr, phase;
1853 /* Request message out phase */
1854 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1857 * Wait for the target to indicate a valid phase by asserting
1858 * REQ. Once this happens, we'll have either a MSGOUT phase
1859 * and can immediately send the ABORT message, or we'll have some
1860 * other phase and will have to source/sink data.
1862 * We really don't care what value was on the bus or what value
1863 * the target sees, so we just handshake.
1866 while (!(tmp = NCR5380_read(STATUS_REG)) & SR_REQ);
1868 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1870 if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1871 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
1873 while (NCR5380_read(STATUS_REG) & SR_REQ);
1874 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1880 phase = PHASE_MSGOUT;
1881 NCR5380_transfer_pio (host, &phase, &len, &msgptr);
1884 * If we got here, and the command completed successfully,
1885 * we're about to go into bus free state.
1888 return len ? -1 : 0;
1891 #if defined(REAL_DMA)
1893 * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1894 * unsigned char *phase, int *count, unsigned char **data)
1896 * Purpose : transfers data in given phase using either real
1899 * Inputs : instance - instance of driver, *phase - pointer to
1900 * what phase is expected, *count - pointer to number of
1901 * bytes to transfer, **data - pointer to data pointer.
1903 * Returns : -1 when different phase is entered without transferring
1904 * maximum number of bytes, 0 if all bytes or transfered or exit
1907 * Also, *phase, *count, *data are modified in place.
1912 static int NCR5380_transfer_dma( struct Scsi_Host *instance,
1913 unsigned char *phase, int *count,
1914 unsigned char **data)
1916 SETUP_HOSTDATA(instance);
1917 register int c = *count;
1918 register unsigned char p = *phase;
1919 unsigned long flags;
1922 if(!sun3_dma_setup_done) {
1923 printk("scsi%d: transfer_dma without setup!\n", HOSTNO);
1926 hostdata->dma_len = c;
1928 DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1929 HOSTNO, (p & SR_IO) ? "reading" : "writing",
1930 c, (p & SR_IO) ? "to" : "from", *data);
1932 /* netbsd turns off ints here, why not be safe and do it too */
1936 /* send start chain */
1937 sun3scsi_dma_start(c, *data);
1940 NCR5380_write(TARGET_COMMAND_REG, 1);
1941 NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1942 NCR5380_write(INITIATOR_COMMAND_REG, 0);
1943 NCR5380_write(MODE_REG, (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR));
1944 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1946 NCR5380_write(TARGET_COMMAND_REG, 0);
1947 NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1948 NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_DATA);
1949 NCR5380_write(MODE_REG, (NCR5380_read(MODE_REG) | MR_DMA_MODE | MR_ENABLE_EOP_INTR));
1950 NCR5380_write(START_DMA_SEND_REG, 0);
1953 #ifdef SUN3_SCSI_VME
1954 dregs->csr |= CSR_DMA_ENABLE;
1957 restore_flags(flags);
1959 sun3_dma_active = 1;
1962 #endif /* defined(REAL_DMA) */
1965 * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1967 * Purpose : run through the various SCSI phases and do as the target
1968 * directs us to. Operates on the currently connected command,
1969 * instance->connected.
1971 * Inputs : instance, instance for which we are doing commands
1973 * Side effects : SCSI things happen, the disconnected queue will be
1974 * modified if a command disconnects, *instance->connected will
1977 * XXX Note : we need to watch for bus free or a reset condition here
1978 * to recover from an unexpected bus free condition.
1981 static void NCR5380_information_transfer (struct Scsi_Host *instance)
1983 SETUP_HOSTDATA(instance);
1984 unsigned long flags;
1985 unsigned char msgout = NOP;
1988 #if defined(REAL_DMA)
1991 unsigned char *data;
1992 unsigned char phase, tmp, extended_msg[10], old_phase=0xff;
1993 Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
1995 #ifdef SUN3_SCSI_VME
1996 dregs->csr |= CSR_INTR;
2000 tmp = NCR5380_read(STATUS_REG);
2001 /* We only have a valid SCSI phase when REQ is asserted */
2003 phase = (tmp & PHASE_MASK);
2004 if (phase != old_phase) {
2006 NCR_PRINT_PHASE(NDEBUG_INFORMATION);
2009 if(phase == PHASE_CMDOUT) {
2011 unsigned long count;
2013 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2014 count = cmd->SCp.buffer->length;
2015 d = cmd->SCp.buffer->address;
2017 count = cmd->SCp.this_residual;
2021 /* this command setup for dma yet? */
2022 if((count > SUN3_DMA_MINSIZE) && (sun3_dma_setup_done
2025 if((cmd->request.cmd == 0) || (cmd->request.cmd == 1)) {
2026 sun3scsi_dma_setup(d, count,
2028 sun3_dma_setup_done = cmd;
2032 #ifdef SUN3_SCSI_VME
2033 dregs->csr |= CSR_INTR;
2038 if (sink && (phase != PHASE_MSGOUT)) {
2039 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2041 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
2043 while (NCR5380_read(STATUS_REG) & SR_REQ);
2044 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2052 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2053 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2054 "aborted\n", HOSTNO);
2057 cmd->result = DID_ERROR << 16;
2063 * If there is no room left in the current buffer in the
2064 * scatter-gather list, move onto the next one.
2066 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2068 --cmd->SCp.buffers_residual;
2069 cmd->SCp.this_residual = cmd->SCp.buffer->length;
2070 cmd->SCp.ptr = cmd->SCp.buffer->address;
2072 /* ++roman: Try to merge some scatter-buffers if
2073 * they are at contiguous physical addresses.
2075 // merge_contiguous_buffers( cmd );
2076 INF_PRINTK("scsi%d: %d bytes and %d buffers left\n",
2077 HOSTNO, cmd->SCp.this_residual,
2078 cmd->SCp.buffers_residual);
2082 * The preferred transfer method is going to be
2083 * PSEUDO-DMA for systems that are strictly PIO,
2084 * since we can let the hardware do the handshaking.
2086 * For this to work, we need to know the transfersize
2087 * ahead of time, since the pseudo-DMA code will sit
2088 * in an unconditional loop.
2091 /* ++roman: I suggest, this should be
2093 * instead of leaving REAL_DMA out.
2096 #if defined(REAL_DMA)
2097 // if (!cmd->device->borken &&
2099 NCR5380_dma_xfer_len(instance,cmd,phase)) > SUN3_DMA_MINSIZE) {
2101 cmd->SCp.phase = phase;
2103 if (NCR5380_transfer_dma(instance, &phase,
2104 &len, (unsigned char **) &cmd->SCp.ptr)) {
2106 * If the watchdog timer fires, all future
2107 * accesses to this device will use the
2109 printk(KERN_NOTICE "scsi%d: switching target %d "
2110 "lun %d to slow handshake\n", HOSTNO,
2111 cmd->target, cmd->lun);
2112 cmd->device->borken = 1;
2113 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2117 cmd->result = DID_ERROR << 16;
2119 /* XXX - need to source or sink data here, as appropriate */
2122 /* ++roman: When using real DMA,
2123 * information_transfer() should return after
2124 * starting DMA since it has nothing more to
2129 cmd->SCp.this_residual -= transfersize - len;
2133 #endif /* defined(REAL_DMA) */
2134 NCR5380_transfer_pio(instance, &phase,
2135 (int *) &cmd->SCp.this_residual, (unsigned char **)
2138 /* if we had intended to dma that command clear it */
2139 if(sun3_dma_setup_done == cmd)
2140 sun3_dma_setup_done = NULL;
2147 NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */
2148 NCR5380_transfer_pio(instance, &phase, &len, &data);
2149 cmd->SCp.Message = tmp;
2153 * Linking lets us reduce the time required to get the
2154 * next command out to the device, hopefully this will
2155 * mean we don't waste another revolution due to the delays
2156 * required by ARBITRATION and another SELECTION.
2158 * In the current implementation proposal, low level drivers
2159 * merely have to start the next command, pointed to by
2160 * next_link, done() is called as with unlinked commands.
2163 case LINKED_CMD_COMPLETE:
2164 case LINKED_FLG_CMD_COMPLETE:
2165 /* Accept message by clearing ACK */
2166 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2168 LNK_PRINTK("scsi%d: target %d lun %d linked command "
2169 "complete.\n", HOSTNO, cmd->target, cmd->lun);
2171 /* Enable reselect interrupts */
2172 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2174 * Sanity check : A linked command should only terminate
2175 * with one of these messages if there are more linked
2176 * commands available.
2179 if (!cmd->next_link) {
2180 printk(KERN_NOTICE "scsi%d: target %d lun %d "
2181 "linked command complete, no next_link\n",
2182 HOSTNO, cmd->target, cmd->lun);
2184 do_abort (instance);
2188 initialize_SCp(cmd->next_link);
2189 /* The next command is still part of this process; copy it
2190 * and don't free it! */
2191 cmd->next_link->tag = cmd->tag;
2192 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2193 LNK_PRINTK("scsi%d: target %d lun %d linked request "
2194 "done, calling scsi_done().\n",
2195 HOSTNO, cmd->target, cmd->lun);
2196 #ifdef NCR5380_STATS
2197 collect_stats(hostdata, cmd);
2199 cmd->scsi_done(cmd);
2200 cmd = hostdata->connected;
2202 #endif /* def LINKED */
2204 case COMMAND_COMPLETE:
2205 /* Accept message by clearing ACK */
2206 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2207 hostdata->connected = NULL;
2208 QU_PRINTK("scsi%d: command for target %d, lun %d "
2209 "completed\n", HOSTNO, cmd->target, cmd->lun);
2211 cmd_free_tag( cmd );
2212 if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
2213 /* Turn a QUEUE FULL status into BUSY, I think the
2214 * mid level cannot handle QUEUE FULL :-( (The
2215 * command is retried after BUSY). Also update our
2216 * queue size to the number of currently issued
2219 /* ++Andreas: the mid level code knows about
2221 TAG_ALLOC *ta = &TagAlloc[cmd->target][cmd->lun];
2222 TAG_PRINTK("scsi%d: target %d lun %d returned "
2223 "QUEUE_FULL after %d commands\n",
2224 HOSTNO, cmd->target, cmd->lun,
2226 if (ta->queue_size > ta->nr_allocated)
2227 ta->nr_allocated = ta->queue_size;
2230 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
2232 /* Enable reselect interrupts */
2233 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2236 * I'm not sure what the correct thing to do here is :
2238 * If the command that just executed is NOT a request
2239 * sense, the obvious thing to do is to set the result
2240 * code to the values of the stored parameters.
2242 * If it was a REQUEST SENSE command, we need some way to
2243 * differentiate between the failure code of the original
2244 * and the failure code of the REQUEST sense - the obvious
2245 * case is success, where we fall through and leave the
2246 * result code unchanged.
2248 * The non-obvious place is where the REQUEST SENSE failed
2251 if (cmd->cmnd[0] != REQUEST_SENSE)
2252 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2253 else if (status_byte(cmd->SCp.Status) != GOOD)
2254 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2257 if ((cmd->cmnd[0] != REQUEST_SENSE) &&
2258 (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2259 ASEN_PRINTK("scsi%d: performing request sense\n",
2261 cmd->cmnd[0] = REQUEST_SENSE;
2262 cmd->cmnd[1] &= 0xe0;
2265 cmd->cmnd[4] = sizeof(cmd->sense_buffer);
2267 cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]);
2270 /* this is initialized from initialize_SCp
2271 cmd->SCp.buffer = NULL;
2272 cmd->SCp.buffers_residual = 0;
2274 cmd->request_buffer = (char *) cmd->sense_buffer;
2275 cmd->request_bufflen = sizeof(cmd->sense_buffer);
2279 LIST(cmd,hostdata->issue_queue);
2280 NEXT(cmd) = hostdata->issue_queue;
2281 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2282 restore_flags(flags);
2283 QU_PRINTK("scsi%d: REQUEST SENSE added to head of "
2284 "issue queue\n", H_NO(cmd));
2286 #endif /* def AUTOSENSE */
2288 #ifdef NCR5380_STATS
2289 collect_stats(hostdata, cmd);
2291 cmd->scsi_done(cmd);
2294 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2296 * Restore phase bits to 0 so an interrupted selection,
2297 * arbitration can resume.
2299 NCR5380_write(TARGET_COMMAND_REG, 0);
2301 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2305 case MESSAGE_REJECT:
2306 /* Accept message by clearing ACK */
2307 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2308 /* Enable reselect interrupts */
2309 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2310 switch (hostdata->last_message) {
2311 case HEAD_OF_QUEUE_TAG:
2312 case ORDERED_QUEUE_TAG:
2313 case SIMPLE_QUEUE_TAG:
2314 /* The target obviously doesn't support tagged
2315 * queuing, even though it announced this ability in
2316 * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2317 * clear 'tagged_supported' and lock the LUN, since
2318 * the command is treated as untagged further on.
2320 cmd->device->tagged_supported = 0;
2321 hostdata->busy[cmd->target] |= (1 << cmd->lun);
2322 cmd->tag = TAG_NONE;
2323 TAG_PRINTK("scsi%d: target %d lun %d rejected "
2324 "QUEUE_TAG message; tagged queuing "
2326 HOSTNO, cmd->target, cmd->lun);
2331 /* Accept message by clearing ACK */
2332 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2335 cmd->device->disconnect = 1;
2336 LIST(cmd,hostdata->disconnected_queue);
2337 NEXT(cmd) = hostdata->disconnected_queue;
2338 hostdata->connected = NULL;
2339 hostdata->disconnected_queue = cmd;
2340 restore_flags(flags);
2341 QU_PRINTK("scsi%d: command for target %d lun %d was "
2342 "moved from connected to the "
2343 "disconnected_queue\n", HOSTNO,
2344 cmd->target, cmd->lun);
2346 * Restore phase bits to 0 so an interrupted selection,
2347 * arbitration can resume.
2349 NCR5380_write(TARGET_COMMAND_REG, 0);
2351 /* Enable reselect interrupts */
2352 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2353 /* Wait for bus free to avoid nasty timeouts */
2354 while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2356 #ifdef SUN3_SCSI_VME
2357 dregs->csr |= CSR_DMA_ENABLE;
2361 * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2362 * operation, in violation of the SCSI spec so we can safely
2363 * ignore SAVE/RESTORE pointers calls.
2365 * Unfortunately, some disks violate the SCSI spec and
2366 * don't issue the required SAVE_POINTERS message before
2367 * disconnecting, and we have to break spec to remain
2371 case RESTORE_POINTERS:
2372 /* Accept message by clearing ACK */
2373 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2374 /* Enable reselect interrupts */
2375 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2377 case EXTENDED_MESSAGE:
2379 * Extended messages are sent in the following format :
2381 * 0 EXTENDED_MESSAGE == 1
2382 * 1 length (includes one byte for code, doesn't
2383 * include first two bytes)
2385 * 3..length+1 arguments
2387 * Start the extended message buffer with the EXTENDED_MESSAGE
2388 * byte, since print_msg() wants the whole thing.
2390 extended_msg[0] = EXTENDED_MESSAGE;
2391 /* Accept first byte by clearing ACK */
2392 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2394 EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO);
2397 data = extended_msg + 1;
2398 phase = PHASE_MSGIN;
2399 NCR5380_transfer_pio(instance, &phase, &len, &data);
2400 EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2401 (int)extended_msg[1], (int)extended_msg[2]);
2403 if (!len && extended_msg[1] <=
2404 (sizeof (extended_msg) - 1)) {
2405 /* Accept third byte by clearing ACK */
2406 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2407 len = extended_msg[1] - 1;
2408 data = extended_msg + 3;
2409 phase = PHASE_MSGIN;
2411 NCR5380_transfer_pio(instance, &phase, &len, &data);
2412 EXT_PRINTK("scsi%d: message received, residual %d\n",
2415 switch (extended_msg[2]) {
2418 case EXTENDED_MODIFY_DATA_POINTER:
2419 case EXTENDED_EXTENDED_IDENTIFY:
2423 printk(KERN_NOTICE "scsi%d: error receiving "
2424 "extended message\n", HOSTNO);
2427 printk(KERN_NOTICE "scsi%d: extended message "
2428 "code %02x length %d is too long\n",
2429 HOSTNO, extended_msg[2], extended_msg[1]);
2432 /* Fall through to reject message */
2435 * If we get something weird that we aren't expecting,
2440 printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO);
2441 print_msg (extended_msg);
2443 } else if (tmp != EXTENDED_MESSAGE)
2444 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2445 "message %02x from target %d, lun %d\n",
2446 HOSTNO, tmp, cmd->target, cmd->lun);
2448 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2450 "code %02x, length %d from target %d, lun %d\n",
2451 HOSTNO, extended_msg[1], extended_msg[0],
2452 cmd->target, cmd->lun);
2455 msgout = MESSAGE_REJECT;
2456 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2459 } /* switch (tmp) */
2464 hostdata->last_message = msgout;
2465 NCR5380_transfer_pio(instance, &phase, &len, &data);
2466 if (msgout == ABORT) {
2468 cmd_free_tag( cmd );
2470 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
2472 hostdata->connected = NULL;
2473 cmd->result = DID_ERROR << 16;
2474 #ifdef NCR5380_STATS
2475 collect_stats(hostdata, cmd);
2477 cmd->scsi_done(cmd);
2478 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2487 * XXX for performance reasons, on machines with a
2488 * PSEUDO-DMA architecture we should probably
2489 * use the dma transfer function.
2491 NCR5380_transfer_pio(instance, &phase, &len,
2497 NCR5380_transfer_pio(instance, &phase, &len, &data);
2498 cmd->SCp.Status = tmp;
2501 printk("scsi%d: unknown phase\n", HOSTNO);
2502 NCR_PRINT(NDEBUG_ANY);
2503 } /* switch(phase) */
2504 } /* if (tmp * SR_REQ) */
2509 * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2511 * Purpose : does reselection, initializing the instance->connected
2512 * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2513 * nexus has been reestablished,
2515 * Inputs : instance - this instance of the NCR5380.
2519 /* it might eventually prove necessary to do a dma setup on
2520 reselection, but it doesn't seem to be needed now -- sam */
2522 static void NCR5380_reselect (struct Scsi_Host *instance)
2524 SETUP_HOSTDATA(instance);
2525 unsigned char target_mask;
2530 unsigned char msg[3];
2531 Scsi_Cmnd *tmp = NULL, *prev;
2532 /* unsigned long flags; */
2535 * Disable arbitration, etc. since the host adapter obviously
2536 * lost, and tell an interrupted NCR5380_select() to restart.
2539 NCR5380_write(MODE_REG, MR_BASE);
2540 hostdata->restart_select = 1;
2542 target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2544 RSL_PRINTK("scsi%d: reselect\n", HOSTNO);
2547 * At this point, we have detected that our SCSI ID is on the bus,
2548 * SEL is true and BSY was false for at least one bus settle delay
2551 * We must assert BSY ourselves, until the target drops the SEL
2555 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2557 while (NCR5380_read(STATUS_REG) & SR_SEL);
2558 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2561 * Wait for target to go into MSGIN.
2564 while (!(NCR5380_read(STATUS_REG) & SR_REQ));
2567 // acknowledge toggle to MSGIN
2568 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(PHASE_MSGIN));
2570 // peek at the byte without really hitting the bus
2571 msg[0] = NCR5380_read(CURRENT_SCSI_DATA_REG);
2574 if (!msg[0] & 0x80) {
2575 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
2580 lun = (msg[0] & 0x07);
2583 * Find the command corresponding to the I_T_L or I_T_L_Q nexus we
2584 * just reestablished, and remove it from the disconnected queue.
2587 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL;
2588 tmp; prev = tmp, tmp = NEXT(tmp) ) {
2589 if ((target_mask == (1 << tmp->target)) && (lun == tmp->lun)
2591 && (tag == tmp->tag)
2595 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2596 NEXT(prev) = NEXT(tmp);
2598 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
2599 hostdata->disconnected_queue = NEXT(tmp);
2607 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
2611 "not in disconnected_queue.\n",
2612 HOSTNO, target_mask, lun
2618 * Since we have an established nexus that we can't do anything
2619 * with, we must abort it.
2625 /* engage dma setup for the command we just saw */
2628 unsigned long count;
2630 if (!tmp->SCp.this_residual && tmp->SCp.buffers_residual) {
2631 count = tmp->SCp.buffer->length;
2632 d = tmp->SCp.buffer->address;
2634 count = tmp->SCp.this_residual;
2638 /* setup this command for dma if not already */
2639 if((count > SUN3_DMA_MINSIZE) && (sun3_dma_setup_done
2642 sun3scsi_dma_setup(d, count,
2644 sun3_dma_setup_done = tmp;
2650 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
2651 /* Accept message by clearing ACK */
2652 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2655 /* If the phase is still MSGIN, the target wants to send some more
2656 * messages. In case it supports tagged queuing, this is probably a
2657 * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2660 if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
2661 /* Accept previous IDENTIFY message by clearing ACK */
2662 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE );
2665 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2666 msg[1] == SIMPLE_QUEUE_TAG)
2668 TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at "
2669 "reselection\n", HOSTNO, target_mask, lun, tag);
2673 hostdata->connected = tmp;
2674 RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n",
2675 HOSTNO, tmp->target, tmp->lun, tmp->tag);
2680 * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2682 * Purpose : abort a command
2684 * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2685 * host byte of the result field to, if zero DID_ABORTED is
2688 * Returns : 0 - success, -1 on failure.
2690 * XXX - there is no way to abort the command that is currently
2691 * connected, you have to wait for it to complete. If this is
2692 * a problem, we could implement longjmp() / setjmp(), setjmp()
2693 * called where the loop started in NCR5380_main().
2696 static int NCR5380_abort (Scsi_Cmnd *cmd)
2698 struct Scsi_Host *instance = cmd->host;
2699 SETUP_HOSTDATA(instance);
2700 Scsi_Cmnd *tmp, **prev;
2701 unsigned long flags;
2703 printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO);
2704 print_Scsi_Cmnd (cmd);
2706 NCR5380_print_status (instance);
2711 ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2712 NCR5380_read(BUS_AND_STATUS_REG),
2713 NCR5380_read(STATUS_REG));
2717 * Case 1 : If the command is the currently executing command,
2718 * we'll set the aborted flag and return control so that
2719 * information transfer routine can exit cleanly.
2722 if (hostdata->connected == cmd) {
2724 ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO);
2726 * We should perform BSY checking, and make sure we haven't slipped
2730 /* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2732 * Since we can't change phases until we've completed the current
2733 * handshake, we have to source or sink a byte of data if the current
2734 * phase is not MSGOUT.
2738 * Return control to the executing NCR drive so we can clear the
2739 * aborted flag and get back into our main loop.
2742 if (do_abort(instance) == 0) {
2743 hostdata->aborted = 1;
2744 hostdata->connected = NULL;
2745 cmd->result = DID_ABORT << 16;
2747 cmd_free_tag( cmd );
2749 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
2751 restore_flags(flags);
2752 cmd->scsi_done(cmd);
2753 return SCSI_ABORT_SUCCESS;
2755 /* restore_flags(flags); */
2756 printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2757 return SCSI_ABORT_ERROR;
2763 * Case 2 : If the command hasn't been issued yet, we simply remove it
2764 * from the issue queue.
2766 for (prev = (Scsi_Cmnd **) &(hostdata->issue_queue),
2767 tmp = (Scsi_Cmnd *) hostdata->issue_queue;
2768 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) )
2770 REMOVE(5, *prev, tmp, NEXT(tmp));
2771 (*prev) = NEXT(tmp);
2773 tmp->result = DID_ABORT << 16;
2774 restore_flags(flags);
2775 ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n",
2777 /* Tagged queuing note: no tag to free here, hasn't been assigned
2779 tmp->scsi_done(tmp);
2780 return SCSI_ABORT_SUCCESS;
2784 * Case 3 : If any commands are connected, we're going to fail the abort
2785 * and let the high level SCSI driver retry at a later time or
2788 * Timeouts, and therefore aborted commands, will be highly unlikely
2789 * and handling them cleanly in this situation would make the common
2790 * case of noresets less efficient, and would pollute our code. So,
2794 if (hostdata->connected) {
2795 restore_flags(flags);
2796 ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO);
2797 return SCSI_ABORT_SNOOZE;
2801 * Case 4: If the command is currently disconnected from the bus, and
2802 * there are no connected commands, we reconnect the I_T_L or
2803 * I_T_L_Q nexus associated with it, go into message out, and send
2806 * This case is especially ugly. In order to reestablish the nexus, we
2807 * need to call NCR5380_select(). The easiest way to implement this
2808 * function was to abort if the bus was busy, and let the interrupt
2809 * handler triggered on the SEL for reselect take care of lost arbitrations
2810 * where necessary, meaning interrupts need to be enabled.
2812 * When interrupts are enabled, the queues may change - so we
2813 * can't remove it from the disconnected queue before selecting it
2814 * because that could cause a failure in hashing the nexus if that
2815 * device reselected.
2817 * Since the queues may change, we can't use the pointers from when we
2820 * So, we must first locate the command, and if NCR5380_select()
2821 * succeeds, then issue the abort, relocate the command and remove
2822 * it from the disconnected queue.
2825 for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp;
2828 restore_flags(flags);
2829 ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO);
2831 if (NCR5380_select (instance, cmd, (int) cmd->tag))
2832 return SCSI_ABORT_BUSY;
2834 ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO);
2836 do_abort (instance);
2840 for (prev = (Scsi_Cmnd **) &(hostdata->disconnected_queue),
2841 tmp = (Scsi_Cmnd *) hostdata->disconnected_queue;
2842 tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) )
2844 REMOVE(5, *prev, tmp, NEXT(tmp));
2847 tmp->result = DID_ABORT << 16;
2848 /* We must unlock the tag/LUN immediately here, since the
2849 * target goes to BUS FREE and doesn't send us another
2850 * message (COMMAND_COMPLETE or the like)
2853 cmd_free_tag( tmp );
2855 hostdata->busy[cmd->target] &= ~(1 << cmd->lun);
2857 restore_flags(flags);
2858 tmp->scsi_done(tmp);
2859 return SCSI_ABORT_SUCCESS;
2864 * Case 5 : If we reached this point, the command was not found in any of
2867 * We probably reached this point because of an unlikely race condition
2868 * between the command completing successfully and the abortion code,
2869 * so we won't panic, but we will notify the user in case something really
2873 restore_flags(flags);
2874 printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully\n"
2875 KERN_INFO " before abortion\n", HOSTNO);
2877 return SCSI_ABORT_NOT_RUNNING;
2882 * Function : int NCR5380_reset (Scsi_Cmnd *cmd, unsigned int reset_flags)
2884 * Purpose : reset the SCSI bus.
2886 * Returns : SCSI_RESET_WAKEUP
2890 static int NCR5380_reset( Scsi_Cmnd *cmd, unsigned int reset_flags)
2892 SETUP_HOSTDATA(cmd->host);
2894 unsigned long flags;
2896 Scsi_Cmnd *connected, *disconnected_queue;
2900 NCR5380_print_status (cmd->host);
2903 NCR5380_write( TARGET_COMMAND_REG,
2904 PHASE_SR_TO_TCR( NCR5380_read(STATUS_REG) ));
2906 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST );
2908 /* reset NCR registers */
2909 NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE );
2910 NCR5380_write( MODE_REG, MR_BASE );
2911 NCR5380_write( TARGET_COMMAND_REG, 0 );
2912 NCR5380_write( SELECT_ENABLE_REG, 0 );
2913 /* ++roman: reset interrupt condition! otherwise no interrupts don't get
2914 * through anymore ... */
2915 (void)NCR5380_read( RESET_PARITY_INTERRUPT_REG );
2917 #if 1 /* XXX Should now be done by midlevel code, but it's broken XXX */
2918 /* XXX see below XXX */
2920 /* MSch: old-style reset: actually abort all command processing here */
2922 /* After the reset, there are no more connected or disconnected commands
2923 * and no busy units; to avoid problems with re-inserting the commands
2924 * into the issue_queue (via scsi_done()), the aborted commands are
2925 * remembered in local variables first.
2929 connected = (Scsi_Cmnd *)hostdata->connected;
2930 hostdata->connected = NULL;
2931 disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue;
2932 hostdata->disconnected_queue = NULL;
2936 for( i = 0; i < 8; ++i )
2937 hostdata->busy[i] = 0;
2939 hostdata->dma_len = 0;
2941 restore_flags(flags);
2943 /* In order to tell the mid-level code which commands were aborted,
2944 * set the command status to DID_RESET and call scsi_done() !!!
2945 * This ultimately aborts processing of these commands in the mid-level.
2948 if ((cmd = connected)) {
2949 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2950 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2951 cmd->scsi_done( cmd );
2954 for (i = 0; (cmd = disconnected_queue); ++i) {
2955 disconnected_queue = NEXT(cmd);
2957 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2958 cmd->scsi_done( cmd );
2961 ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i);
2964 /* since all commands have been explicitly terminated, we need to tell
2965 * the midlevel code that the reset was SUCCESSFUL, and there is no
2966 * need to 'wake up' the commands by a request_sense
2968 return SCSI_RESET_SUCCESS | SCSI_RESET_BUS_RESET;
2971 /* MSch: new-style reset handling: let the mid-level do what it can */
2973 /* ++guenther: MID-LEVEL IS STILL BROKEN.
2974 * Mid-level is supposed to requeue all commands that were active on the
2975 * various low-level queues. In fact it does this, but that's not enough
2976 * because all these commands are subject to timeout. And if a timeout
2977 * happens for any removed command, *_abort() is called but all queues
2978 * are now empty. Abort then gives up the falcon lock, which is fatal,
2979 * since the mid-level will queue more commands and must have the lock
2980 * (it's all happening inside timer interrupt handler!!).
2981 * Even worse, abort will return NOT_RUNNING for all those commands not
2982 * on any queue, so they won't be retried ...
2984 * Conclusion: either scsi.c disables timeout for all resetted commands
2985 * immediately, or we loose! As of linux-2.0.20 it doesn't.
2988 /* After the reset, there are no more connected or disconnected commands
2989 * and no busy units; so clear the low-level status here to avoid
2990 * conflicts when the mid-level code tries to wake up the affected
2994 if (hostdata->issue_queue)
2995 ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2996 if (hostdata->connected)
2997 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2998 if (hostdata->disconnected_queue)
2999 ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
3003 hostdata->issue_queue = NULL;
3004 hostdata->connected = NULL;
3005 hostdata->disconnected_queue = NULL;
3009 for( i = 0; i < 8; ++i )
3010 hostdata->busy[i] = 0;
3012 hostdata->dma_len = 0;
3014 restore_flags(flags);
3016 /* we did no complete reset of all commands, so a wakeup is required */
3017 return SCSI_RESET_WAKEUP | SCSI_RESET_BUS_RESET;
3021 /* Local Variables: */