[SCSI] NCR5380: Use scsi_eh API for REQUEST_SENSE invocation
[linux-2.6.git] / drivers / scsi / atari_NCR5380.c
1 /*
2  * NCR 5380 generic driver routines.  These should make it *trivial*
3  *      to implement 5380 SCSI drivers under Linux with a non-trantor
4  *      architecture.
5  *
6  *      Note that these routines also work with NR53c400 family chips.
7  *
8  * Copyright 1993, Drew Eckhardt
9  *      Visionary Computing
10  *      (Unix and Linux consulting and custom programming)
11  *      drew@colorado.edu
12  *      +1 (303) 666-5836
13  *
14  * DISTRIBUTION RELEASE 6.
15  *
16  * For more information, please consult
17  *
18  * NCR 5380 Family
19  * SCSI Protocol Controller
20  * Databook
21  *
22  * NCR Microelectronics
23  * 1635 Aeroplaza Drive
24  * Colorado Springs, CO 80916
25  * 1+ (719) 578-3400
26  * 1+ (800) 334-5454
27  */
28
29 /*
30  * ++roman: To port the 5380 driver to the Atari, I had to do some changes in
31  * this file, too:
32  *
33  *  - Some of the debug statements were incorrect (undefined variables and the
34  *    like). I fixed that.
35  *
36  *  - In information_transfer(), I think a #ifdef was wrong. Looking at the
37  *    possible DMA transfer size should also happen for REAL_DMA. I added this
38  *    in the #if statement.
39  *
40  *  - When using real DMA, information_transfer() should return in a DATAOUT
41  *    phase after starting the DMA. It has nothing more to do.
42  *
43  *  - The interrupt service routine should run main after end of DMA, too (not
44  *    only after RESELECTION interrupts). Additionally, it should _not_ test
45  *    for more interrupts after running main, since a DMA process may have
46  *    been started and interrupts are turned on now. The new int could happen
47  *    inside the execution of NCR5380_intr(), leading to recursive
48  *    calls.
49  *
50  *  - I've added a function merge_contiguous_buffers() that tries to
51  *    merge scatter-gather buffers that are located at contiguous
52  *    physical addresses and can be processed with the same DMA setup.
53  *    Since most scatter-gather operations work on a page (4K) of
54  *    4 buffers (1K), in more than 90% of all cases three interrupts and
55  *    DMA setup actions are saved.
56  *
57  * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA
58  *    and USLEEP, because these were messing up readability and will never be
59  *    needed for Atari SCSI.
60  *
61  * - I've revised the NCR5380_main() calling scheme (relax the 'main_running'
62  *   stuff), and 'main' is executed in a bottom half if awoken by an
63  *   interrupt.
64  *
65  * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..."
66  *   constructs. In my eyes, this made the source rather unreadable, so I
67  *   finally replaced that by the *_PRINTK() macros.
68  *
69  */
70
71 /*
72  * Further development / testing that should be done :
73  * 1.  Test linked command handling code after Eric is ready with
74  *     the high level code.
75  */
76 #include <scsi/scsi_dbg.h>
77 #include <scsi/scsi_transport_spi.h>
78
79 #if (NDEBUG & NDEBUG_LISTS)
80 #define LIST(x, y)                                              \
81         do {                                                    \
82                 printk("LINE:%d   Adding %p to %p\n",           \
83                        __LINE__, (void*)(x), (void*)(y));       \
84                 if ((x) == (y))                                 \
85                         udelay(5);                              \
86         } while (0)
87 #define REMOVE(w, x, y, z)                                      \
88         do {                                                    \
89                 printk("LINE:%d   Removing: %p->%p  %p->%p \n", \
90                        __LINE__, (void*)(w), (void*)(x),        \
91                        (void*)(y), (void*)(z));                 \
92                 if ((x) == (y))                                 \
93                         udelay(5);                              \
94         } while (0)
95 #else
96 #define LIST(x,y)
97 #define REMOVE(w,x,y,z)
98 #endif
99
100 #ifndef notyet
101 #undef LINKED
102 #endif
103
104 /*
105  * Design
106  * Issues :
107  *
108  * The other Linux SCSI drivers were written when Linux was Intel PC-only,
109  * and specifically for each board rather than each chip.  This makes their
110  * adaptation to platforms like the Mac (Some of which use NCR5380's)
111  * more difficult than it has to be.
112  *
113  * Also, many of the SCSI drivers were written before the command queuing
114  * routines were implemented, meaning their implementations of queued
115  * commands were hacked on rather than designed in from the start.
116  *
117  * When I designed the Linux SCSI drivers I figured that
118  * while having two different SCSI boards in a system might be useful
119  * for debugging things, two of the same type wouldn't be used.
120  * Well, I was wrong and a number of users have mailed me about running
121  * multiple high-performance SCSI boards in a server.
122  *
123  * Finally, when I get questions from users, I have no idea what
124  * revision of my driver they are running.
125  *
126  * This driver attempts to address these problems :
127  * This is a generic 5380 driver.  To use it on a different platform,
128  * one simply writes appropriate system specific macros (ie, data
129  * transfer - some PC's will use the I/O bus, 68K's must use
130  * memory mapped) and drops this file in their 'C' wrapper.
131  *
132  * As far as command queueing, two queues are maintained for
133  * each 5380 in the system - commands that haven't been issued yet,
134  * and commands that are currently executing.  This means that an
135  * unlimited number of commands may be queued, letting
136  * more commands propagate from the higher driver levels giving higher
137  * throughput.  Note that both I_T_L and I_T_L_Q nexuses are supported,
138  * allowing multiple commands to propagate all the way to a SCSI-II device
139  * while a command is already executing.
140  *
141  * To solve the multiple-boards-in-the-same-system problem,
142  * there is a separate instance structure for each instance
143  * of a 5380 in the system.  So, multiple NCR5380 drivers will
144  * be able to coexist with appropriate changes to the high level
145  * SCSI code.
146  *
147  * A NCR5380_PUBLIC_REVISION macro is provided, with the release
148  * number (updated for each public release) printed by the
149  * NCR5380_print_options command, which should be called from the
150  * wrapper detect function, so that I know what release of the driver
151  * users are using.
152  *
153  * Issues specific to the NCR5380 :
154  *
155  * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead
156  * piece of hardware that requires you to sit in a loop polling for
157  * the REQ signal as long as you are connected.  Some devices are
158  * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect
159  * while doing long seek operations.
160  *
161  * The workaround for this is to keep track of devices that have
162  * disconnected.  If the device hasn't disconnected, for commands that
163  * should disconnect, we do something like
164  *
165  * while (!REQ is asserted) { sleep for N usecs; poll for M usecs }
166  *
167  * Some tweaking of N and M needs to be done.  An algorithm based
168  * on "time to data" would give the best results as long as short time
169  * to datas (ie, on the same track) were considered, however these
170  * broken devices are the exception rather than the rule and I'd rather
171  * spend my time optimizing for the normal case.
172  *
173  * Architecture :
174  *
175  * At the heart of the design is a coroutine, NCR5380_main,
176  * which is started when not running by the interrupt handler,
177  * timer, and queue command function.  It attempts to establish
178  * I_T_L or I_T_L_Q nexuses by removing the commands from the
179  * issue queue and calling NCR5380_select() if a nexus
180  * is not established.
181  *
182  * Once a nexus is established, the NCR5380_information_transfer()
183  * phase goes through the various phases as instructed by the target.
184  * if the target goes into MSG IN and sends a DISCONNECT message,
185  * the command structure is placed into the per instance disconnected
186  * queue, and NCR5380_main tries to find more work.  If USLEEP
187  * was defined, and the target is idle for too long, the system
188  * will try to sleep.
189  *
190  * If a command has disconnected, eventually an interrupt will trigger,
191  * calling NCR5380_intr()  which will in turn call NCR5380_reselect
192  * to reestablish a nexus.  This will run main if necessary.
193  *
194  * On command termination, the done function will be called as
195  * appropriate.
196  *
197  * SCSI pointers are maintained in the SCp field of SCSI command
198  * structures, being initialized after the command is connected
199  * in NCR5380_select, and set as appropriate in NCR5380_information_transfer.
200  * Note that in violation of the standard, an implicit SAVE POINTERS operation
201  * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS.
202  */
203
204 /*
205  * Using this file :
206  * This file a skeleton Linux SCSI driver for the NCR 5380 series
207  * of chips.  To use it, you write an architecture specific functions
208  * and macros and include this file in your driver.
209  *
210  * These macros control options :
211  * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically
212  *      for commands that return with a CHECK CONDITION status.
213  *
214  * LINKED - if defined, linked commands are supported.
215  *
216  * REAL_DMA - if defined, REAL DMA is used during the data transfer phases.
217  *
218  * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible
219  *
220  * These macros MUST be defined :
221  *
222  * NCR5380_read(register)  - read from the specified register
223  *
224  * NCR5380_write(register, value) - write to the specific register
225  *
226  * Either real DMA *or* pseudo DMA may be implemented
227  * REAL functions :
228  * NCR5380_REAL_DMA should be defined if real DMA is to be used.
229  * Note that the DMA setup functions should return the number of bytes
230  *      that they were able to program the controller for.
231  *
232  * Also note that generic i386/PC versions of these macros are
233  *      available as NCR5380_i386_dma_write_setup,
234  *      NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual.
235  *
236  * NCR5380_dma_write_setup(instance, src, count) - initialize
237  * NCR5380_dma_read_setup(instance, dst, count) - initialize
238  * NCR5380_dma_residual(instance); - residual count
239  *
240  * PSEUDO functions :
241  * NCR5380_pwrite(instance, src, count)
242  * NCR5380_pread(instance, dst, count);
243  *
244  * If nothing specific to this implementation needs doing (ie, with external
245  * hardware), you must also define
246  *
247  * NCR5380_queue_command
248  * NCR5380_reset
249  * NCR5380_abort
250  * NCR5380_proc_info
251  *
252  * to be the global entry points into the specific driver, ie
253  * #define NCR5380_queue_command t128_queue_command.
254  *
255  * If this is not done, the routines will be defined as static functions
256  * with the NCR5380* names and the user must provide a globally
257  * accessible wrapper function.
258  *
259  * The generic driver is initialized by calling NCR5380_init(instance),
260  * after setting the appropriate host specific fields and ID.  If the
261  * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance,
262  * possible) function may be used.  Before the specific driver initialization
263  * code finishes, NCR5380_print_options should be called.
264  */
265
266 static struct Scsi_Host *first_instance = NULL;
267 static struct scsi_host_template *the_template = NULL;
268
269 /* Macros ease life... :-) */
270 #define SETUP_HOSTDATA(in)                              \
271     struct NCR5380_hostdata *hostdata =                 \
272         (struct NCR5380_hostdata *)(in)->hostdata
273 #define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata)
274
275 #define NEXT(cmd)               ((Scsi_Cmnd *)(cmd)->host_scribble)
276 #define SET_NEXT(cmd,next)      ((cmd)->host_scribble = (void *)(next))
277 #define NEXTADDR(cmd)           ((Scsi_Cmnd **)&(cmd)->host_scribble)
278
279 #define HOSTNO          instance->host_no
280 #define H_NO(cmd)       (cmd)->device->host->host_no
281
282 #ifdef SUPPORT_TAGS
283
284 /*
285  * Functions for handling tagged queuing
286  * =====================================
287  *
288  * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes:
289  *
290  * Using consecutive numbers for the tags is no good idea in my eyes. There
291  * could be wrong re-usings if the counter (8 bit!) wraps and some early
292  * command has been preempted for a long time. My solution: a bitfield for
293  * remembering used tags.
294  *
295  * There's also the problem that each target has a certain queue size, but we
296  * cannot know it in advance :-( We just see a QUEUE_FULL status being
297  * returned. So, in this case, the driver internal queue size assumption is
298  * reduced to the number of active tags if QUEUE_FULL is returned by the
299  * target. The command is returned to the mid-level, but with status changed
300  * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL
301  * correctly.
302  *
303  * We're also not allowed running tagged commands as long as an untagged
304  * command is active. And REQUEST SENSE commands after a contingent allegiance
305  * condition _must_ be untagged. To keep track whether an untagged command has
306  * been issued, the host->busy array is still employed, as it is without
307  * support for tagged queuing.
308  *
309  * One could suspect that there are possible race conditions between
310  * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the
311  * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(),
312  * which already guaranteed to be running at most once. It is also the only
313  * place where tags/LUNs are allocated. So no other allocation can slip
314  * between that pair, there could only happen a reselection, which can free a
315  * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes
316  * important: the tag bit must be cleared before 'nr_allocated' is decreased.
317  */
318
319 /* -1 for TAG_NONE is not possible with unsigned char cmd->tag */
320 #undef TAG_NONE
321 #define TAG_NONE 0xff
322
323 typedef struct {
324         DECLARE_BITMAP(allocated, MAX_TAGS);
325         int nr_allocated;
326         int queue_size;
327 } TAG_ALLOC;
328
329 static TAG_ALLOC TagAlloc[8][8];        /* 8 targets and 8 LUNs */
330
331
332 static void __init init_tags(void)
333 {
334         int target, lun;
335         TAG_ALLOC *ta;
336
337         if (!setup_use_tagged_queuing)
338                 return;
339
340         for (target = 0; target < 8; ++target) {
341                 for (lun = 0; lun < 8; ++lun) {
342                         ta = &TagAlloc[target][lun];
343                         bitmap_zero(ta->allocated, MAX_TAGS);
344                         ta->nr_allocated = 0;
345                         /* At the beginning, assume the maximum queue size we could
346                          * support (MAX_TAGS). This value will be decreased if the target
347                          * returns QUEUE_FULL status.
348                          */
349                         ta->queue_size = MAX_TAGS;
350                 }
351         }
352 }
353
354
355 /* Check if we can issue a command to this LUN: First see if the LUN is marked
356  * busy by an untagged command. If the command should use tagged queuing, also
357  * check that there is a free tag and the target's queue won't overflow. This
358  * function should be called with interrupts disabled to avoid race
359  * conditions.
360  */
361
362 static int is_lun_busy(Scsi_Cmnd *cmd, int should_be_tagged)
363 {
364         SETUP_HOSTDATA(cmd->device->host);
365
366         if (hostdata->busy[cmd->device->id] & (1 << cmd->device->lun))
367                 return 1;
368         if (!should_be_tagged ||
369             !setup_use_tagged_queuing || !cmd->device->tagged_supported)
370                 return 0;
371         if (TagAlloc[cmd->device->id][cmd->device->lun].nr_allocated >=
372             TagAlloc[cmd->device->id][cmd->device->lun].queue_size) {
373                 TAG_PRINTK("scsi%d: target %d lun %d: no free tags\n",
374                            H_NO(cmd), cmd->device->id, cmd->device->lun);
375                 return 1;
376         }
377         return 0;
378 }
379
380
381 /* Allocate a tag for a command (there are no checks anymore, check_lun_busy()
382  * must be called before!), or reserve the LUN in 'busy' if the command is
383  * untagged.
384  */
385
386 static void cmd_get_tag(Scsi_Cmnd *cmd, int should_be_tagged)
387 {
388         SETUP_HOSTDATA(cmd->device->host);
389
390         /* If we or the target don't support tagged queuing, allocate the LUN for
391          * an untagged command.
392          */
393         if (!should_be_tagged ||
394             !setup_use_tagged_queuing || !cmd->device->tagged_supported) {
395                 cmd->tag = TAG_NONE;
396                 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
397                 TAG_PRINTK("scsi%d: target %d lun %d now allocated by untagged "
398                            "command\n", H_NO(cmd), cmd->device->id, cmd->device->lun);
399         } else {
400                 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
401
402                 cmd->tag = find_first_zero_bit(ta->allocated, MAX_TAGS);
403                 set_bit(cmd->tag, ta->allocated);
404                 ta->nr_allocated++;
405                 TAG_PRINTK("scsi%d: using tag %d for target %d lun %d "
406                            "(now %d tags in use)\n",
407                            H_NO(cmd), cmd->tag, cmd->device->id,
408                            cmd->device->lun, ta->nr_allocated);
409         }
410 }
411
412
413 /* Mark the tag of command 'cmd' as free, or in case of an untagged command,
414  * unlock the LUN.
415  */
416
417 static void cmd_free_tag(Scsi_Cmnd *cmd)
418 {
419         SETUP_HOSTDATA(cmd->device->host);
420
421         if (cmd->tag == TAG_NONE) {
422                 hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
423                 TAG_PRINTK("scsi%d: target %d lun %d untagged cmd finished\n",
424                            H_NO(cmd), cmd->device->id, cmd->device->lun);
425         } else if (cmd->tag >= MAX_TAGS) {
426                 printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n",
427                        H_NO(cmd), cmd->tag);
428         } else {
429                 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
430                 clear_bit(cmd->tag, ta->allocated);
431                 ta->nr_allocated--;
432                 TAG_PRINTK("scsi%d: freed tag %d for target %d lun %d\n",
433                            H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun);
434         }
435 }
436
437
438 static void free_all_tags(void)
439 {
440         int target, lun;
441         TAG_ALLOC *ta;
442
443         if (!setup_use_tagged_queuing)
444                 return;
445
446         for (target = 0; target < 8; ++target) {
447                 for (lun = 0; lun < 8; ++lun) {
448                         ta = &TagAlloc[target][lun];
449                         bitmap_zero(ta->allocated, MAX_TAGS);
450                         ta->nr_allocated = 0;
451                 }
452         }
453 }
454
455 #endif /* SUPPORT_TAGS */
456
457
458 /*
459  * Function: void merge_contiguous_buffers( Scsi_Cmnd *cmd )
460  *
461  * Purpose: Try to merge several scatter-gather requests into one DMA
462  *    transfer. This is possible if the scatter buffers lie on
463  *    physical contiguous addresses.
464  *
465  * Parameters: Scsi_Cmnd *cmd
466  *    The command to work on. The first scatter buffer's data are
467  *    assumed to be already transfered into ptr/this_residual.
468  */
469
470 static void merge_contiguous_buffers(Scsi_Cmnd *cmd)
471 {
472         unsigned long endaddr;
473 #if (NDEBUG & NDEBUG_MERGING)
474         unsigned long oldlen = cmd->SCp.this_residual;
475         int cnt = 1;
476 #endif
477
478         for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1;
479              cmd->SCp.buffers_residual &&
480              virt_to_phys(page_address(cmd->SCp.buffer[1].page) +
481                           cmd->SCp.buffer[1].offset) == endaddr;) {
482                 MER_PRINTK("VTOP(%p) == %08lx -> merging\n",
483                            page_address(cmd->SCp.buffer[1].page), endaddr);
484 #if (NDEBUG & NDEBUG_MERGING)
485                 ++cnt;
486 #endif
487                 ++cmd->SCp.buffer;
488                 --cmd->SCp.buffers_residual;
489                 cmd->SCp.this_residual += cmd->SCp.buffer->length;
490                 endaddr += cmd->SCp.buffer->length;
491         }
492 #if (NDEBUG & NDEBUG_MERGING)
493         if (oldlen != cmd->SCp.this_residual)
494                 MER_PRINTK("merged %d buffers from %p, new length %08x\n",
495                            cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
496 #endif
497 }
498
499 /*
500  * Function : void initialize_SCp(Scsi_Cmnd *cmd)
501  *
502  * Purpose : initialize the saved data pointers for cmd to point to the
503  *      start of the buffer.
504  *
505  * Inputs : cmd - Scsi_Cmnd structure to have pointers reset.
506  */
507
508 static inline void initialize_SCp(Scsi_Cmnd *cmd)
509 {
510         /*
511          * Initialize the Scsi Pointer field so that all of the commands in the
512          * various queues are valid.
513          */
514
515         if (cmd->use_sg) {
516                 cmd->SCp.buffer = (struct scatterlist *)cmd->request_buffer;
517                 cmd->SCp.buffers_residual = cmd->use_sg - 1;
518                 cmd->SCp.ptr = (char *)page_address(cmd->SCp.buffer->page) +
519                                cmd->SCp.buffer->offset;
520                 cmd->SCp.this_residual = cmd->SCp.buffer->length;
521                 /* ++roman: Try to merge some scatter-buffers if they are at
522                  * contiguous physical addresses.
523                  */
524                 merge_contiguous_buffers(cmd);
525         } else {
526                 cmd->SCp.buffer = NULL;
527                 cmd->SCp.buffers_residual = 0;
528                 cmd->SCp.ptr = (char *)cmd->request_buffer;
529                 cmd->SCp.this_residual = cmd->request_bufflen;
530         }
531 }
532
533 #include <linux/delay.h>
534
535 #if NDEBUG
536 static struct {
537         unsigned char mask;
538         const char *name;
539 } signals[] = {
540         { SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" },
541         { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD,  "CD" }, { SR_IO, "IO" },
542         { SR_SEL, "SEL" }, {0, NULL}
543 }, basrs[] = {
544         {BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}
545 }, icrs[] = {
546         {ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"},
547         {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"},
548         {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"},
549         {0, NULL}
550 }, mrs[] = {
551         {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"},
552         {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR,
553         "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"},
554         {MR_MONITOR_BSY, "MODE MONITOR BSY"},
555         {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"},
556         {0, NULL}
557 };
558
559 /*
560  * Function : void NCR5380_print(struct Scsi_Host *instance)
561  *
562  * Purpose : print the SCSI bus signals for debugging purposes
563  *
564  * Input : instance - which NCR5380
565  */
566
567 static void NCR5380_print(struct Scsi_Host *instance)
568 {
569         unsigned char status, data, basr, mr, icr, i;
570         unsigned long flags;
571
572         local_irq_save(flags);
573         data = NCR5380_read(CURRENT_SCSI_DATA_REG);
574         status = NCR5380_read(STATUS_REG);
575         mr = NCR5380_read(MODE_REG);
576         icr = NCR5380_read(INITIATOR_COMMAND_REG);
577         basr = NCR5380_read(BUS_AND_STATUS_REG);
578         local_irq_restore(flags);
579         printk("STATUS_REG: %02x ", status);
580         for (i = 0; signals[i].mask; ++i)
581                 if (status & signals[i].mask)
582                         printk(",%s", signals[i].name);
583         printk("\nBASR: %02x ", basr);
584         for (i = 0; basrs[i].mask; ++i)
585                 if (basr & basrs[i].mask)
586                         printk(",%s", basrs[i].name);
587         printk("\nICR: %02x ", icr);
588         for (i = 0; icrs[i].mask; ++i)
589                 if (icr & icrs[i].mask)
590                         printk(",%s", icrs[i].name);
591         printk("\nMODE: %02x ", mr);
592         for (i = 0; mrs[i].mask; ++i)
593                 if (mr & mrs[i].mask)
594                         printk(",%s", mrs[i].name);
595         printk("\n");
596 }
597
598 static struct {
599         unsigned char value;
600         const char *name;
601 } phases[] = {
602         {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
603         {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
604         {PHASE_UNKNOWN, "UNKNOWN"}
605 };
606
607 /*
608  * Function : void NCR5380_print_phase(struct Scsi_Host *instance)
609  *
610  * Purpose : print the current SCSI phase for debugging purposes
611  *
612  * Input : instance - which NCR5380
613  */
614
615 static void NCR5380_print_phase(struct Scsi_Host *instance)
616 {
617         unsigned char status;
618         int i;
619
620         status = NCR5380_read(STATUS_REG);
621         if (!(status & SR_REQ))
622                 printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO);
623         else {
624                 for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
625                      (phases[i].value != (status & PHASE_MASK)); ++i)
626                         ;
627                 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name);
628         }
629 }
630
631 #else /* !NDEBUG */
632
633 /* dummies... */
634 static inline void NCR5380_print(struct Scsi_Host *instance)
635 {
636 };
637 static inline void NCR5380_print_phase(struct Scsi_Host *instance)
638 {
639 };
640
641 #endif
642
643 /*
644  * ++roman: New scheme of calling NCR5380_main()
645  *
646  * If we're not in an interrupt, we can call our main directly, it cannot be
647  * already running. Else, we queue it on a task queue, if not 'main_running'
648  * tells us that a lower level is already executing it. This way,
649  * 'main_running' needs not be protected in a special way.
650  *
651  * queue_main() is a utility function for putting our main onto the task
652  * queue, if main_running is false. It should be called only from a
653  * interrupt or bottom half.
654  */
655
656 #include <linux/workqueue.h>
657 #include <linux/interrupt.h>
658
659 static volatile int main_running;
660 static DECLARE_WORK(NCR5380_tqueue, NCR5380_main);
661
662 static inline void queue_main(void)
663 {
664         if (!main_running) {
665                 /* If in interrupt and NCR5380_main() not already running,
666                    queue it on the 'immediate' task queue, to be processed
667                    immediately after the current interrupt processing has
668                    finished. */
669                 schedule_work(&NCR5380_tqueue);
670         }
671         /* else: nothing to do: the running NCR5380_main() will pick up
672            any newly queued command. */
673 }
674
675
676 static inline void NCR5380_all_init(void)
677 {
678         static int done = 0;
679         if (!done) {
680                 INI_PRINTK("scsi : NCR5380_all_init()\n");
681                 done = 1;
682         }
683 }
684
685
686 /*
687  * Function : void NCR58380_print_options (struct Scsi_Host *instance)
688  *
689  * Purpose : called by probe code indicating the NCR5380 driver
690  *           options that were selected.
691  *
692  * Inputs : instance, pointer to this instance.  Unused.
693  */
694
695 static void __init NCR5380_print_options(struct Scsi_Host *instance)
696 {
697         printk(" generic options"
698 #ifdef AUTOSENSE
699                " AUTOSENSE"
700 #endif
701 #ifdef REAL_DMA
702                " REAL DMA"
703 #endif
704 #ifdef PARITY
705                " PARITY"
706 #endif
707 #ifdef SUPPORT_TAGS
708                " SCSI-2 TAGGED QUEUING"
709 #endif
710                );
711         printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
712 }
713
714 /*
715  * Function : void NCR5380_print_status (struct Scsi_Host *instance)
716  *
717  * Purpose : print commands in the various queues, called from
718  *      NCR5380_abort and NCR5380_debug to aid debugging.
719  *
720  * Inputs : instance, pointer to this instance.
721  */
722
723 static void NCR5380_print_status(struct Scsi_Host *instance)
724 {
725         char *pr_bfr;
726         char *start;
727         int len;
728
729         NCR_PRINT(NDEBUG_ANY);
730         NCR_PRINT_PHASE(NDEBUG_ANY);
731
732         pr_bfr = (char *)__get_free_page(GFP_ATOMIC);
733         if (!pr_bfr) {
734                 printk("NCR5380_print_status: no memory for print buffer\n");
735                 return;
736         }
737         len = NCR5380_proc_info(instance, pr_bfr, &start, 0, PAGE_SIZE, 0);
738         pr_bfr[len] = 0;
739         printk("\n%s\n", pr_bfr);
740         free_page((unsigned long)pr_bfr);
741 }
742
743
744 /******************************************/
745 /*
746  * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
747  *
748  * *buffer: I/O buffer
749  * **start: if inout == FALSE pointer into buffer where user read should start
750  * offset: current offset
751  * length: length of buffer
752  * hostno: Scsi_Host host_no
753  * inout: TRUE - user is writing; FALSE - user is reading
754  *
755  * Return the number of bytes read from or written
756 */
757
758 #undef SPRINTF
759 #define SPRINTF(fmt,args...)                                                    \
760         do {                                                                    \
761                 if (pos + strlen(fmt) + 20 /* slop */ < buffer + length)        \
762                         pos += sprintf(pos, fmt , ## args);                     \
763         } while(0)
764 static char *lprint_Scsi_Cmnd(Scsi_Cmnd *cmd, char *pos, char *buffer, int length);
765
766 static int NCR5380_proc_info(struct Scsi_Host *instance, char *buffer,
767                              char **start, off_t offset, int length, int inout)
768 {
769         char *pos = buffer;
770         struct NCR5380_hostdata *hostdata;
771         Scsi_Cmnd *ptr;
772         unsigned long flags;
773         off_t begin = 0;
774 #define check_offset()                                  \
775         do {                                            \
776                 if (pos - buffer < offset - begin) {    \
777                         begin += pos - buffer;          \
778                         pos = buffer;                   \
779                 }                                       \
780         } while (0)
781
782         hostdata = (struct NCR5380_hostdata *)instance->hostdata;
783
784         if (inout)                      /* Has data been written to the file ? */
785                 return -ENOSYS;         /* Currently this is a no-op */
786         SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
787         check_offset();
788         local_irq_save(flags);
789         SPRINTF("NCR5380: coroutine is%s running.\n",
790                 main_running ? "" : "n't");
791         check_offset();
792         if (!hostdata->connected)
793                 SPRINTF("scsi%d: no currently connected command\n", HOSTNO);
794         else
795                 pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected,
796                                        pos, buffer, length);
797         SPRINTF("scsi%d: issue_queue\n", HOSTNO);
798         check_offset();
799         for (ptr = (Scsi_Cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) {
800                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
801                 check_offset();
802         }
803
804         SPRINTF("scsi%d: disconnected_queue\n", HOSTNO);
805         check_offset();
806         for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr;
807              ptr = NEXT(ptr)) {
808                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
809                 check_offset();
810         }
811
812         local_irq_restore(flags);
813         *start = buffer + (offset - begin);
814         if (pos - buffer < offset - begin)
815                 return 0;
816         else if (pos - buffer - (offset - begin) < length)
817                 return pos - buffer - (offset - begin);
818         return length;
819 }
820
821 static char *lprint_Scsi_Cmnd(Scsi_Cmnd *cmd, char *pos, char *buffer, int length)
822 {
823         int i, s;
824         unsigned char *command;
825         SPRINTF("scsi%d: destination target %d, lun %d\n",
826                 H_NO(cmd), cmd->device->id, cmd->device->lun);
827         SPRINTF("        command = ");
828         command = cmd->cmnd;
829         SPRINTF("%2d (0x%02x)", command[0], command[0]);
830         for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
831                 SPRINTF(" %02x", command[i]);
832         SPRINTF("\n");
833         return pos;
834 }
835
836
837 /*
838  * Function : void NCR5380_init (struct Scsi_Host *instance)
839  *
840  * Purpose : initializes *instance and corresponding 5380 chip.
841  *
842  * Inputs : instance - instantiation of the 5380 driver.
843  *
844  * Notes : I assume that the host, hostno, and id bits have been
845  *      set correctly.  I don't care about the irq and other fields.
846  *
847  */
848
849 static int NCR5380_init(struct Scsi_Host *instance, int flags)
850 {
851         int i;
852         SETUP_HOSTDATA(instance);
853
854         NCR5380_all_init();
855
856         hostdata->aborted = 0;
857         hostdata->id_mask = 1 << instance->this_id;
858         hostdata->id_higher_mask = 0;
859         for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
860                 if (i > hostdata->id_mask)
861                         hostdata->id_higher_mask |= i;
862         for (i = 0; i < 8; ++i)
863                 hostdata->busy[i] = 0;
864 #ifdef SUPPORT_TAGS
865         init_tags();
866 #endif
867 #if defined (REAL_DMA)
868         hostdata->dma_len = 0;
869 #endif
870         hostdata->targets_present = 0;
871         hostdata->connected = NULL;
872         hostdata->issue_queue = NULL;
873         hostdata->disconnected_queue = NULL;
874         hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT;
875
876         if (!the_template) {
877                 the_template = instance->hostt;
878                 first_instance = instance;
879         }
880
881 #ifndef AUTOSENSE
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 */
887
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);
892
893         return 0;
894 }
895
896 /*
897  * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd,
898  *      void (*done)(Scsi_Cmnd *))
899  *
900  * Purpose :  enqueues a SCSI command
901  *
902  * Inputs : cmd - SCSI command, done - function called on completion, with
903  *      a pointer to the command descriptor.
904  *
905  * Returns : 0
906  *
907  * Side effects :
908  *      cmd is added to the per instance issue_queue, with minor
909  *      twiddling done to the host specific fields of cmd.  If the
910  *      main coroutine is not running, it is restarted.
911  *
912  */
913
914 static int NCR5380_queue_command(Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
915 {
916         SETUP_HOSTDATA(cmd->device->host);
917         Scsi_Cmnd *tmp;
918         int oldto;
919         unsigned long flags;
920
921 #if (NDEBUG & NDEBUG_NO_WRITE)
922         switch (cmd->cmnd[0]) {
923         case WRITE_6:
924         case WRITE_10:
925                 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
926                        H_NO(cmd));
927                 cmd->result = (DID_ERROR << 16);
928                 done(cmd);
929                 return 0;
930         }
931 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
932
933 #ifdef NCR5380_STATS
934 # if 0
935         if (!hostdata->connected && !hostdata->issue_queue &&
936             !hostdata->disconnected_queue) {
937                 hostdata->timebase = jiffies;
938         }
939 # endif
940 # ifdef NCR5380_STAT_LIMIT
941         if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
942 # endif
943                 switch (cmd->cmnd[0]) {
944                 case WRITE:
945                 case WRITE_6:
946                 case WRITE_10:
947                         hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
948                         hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen;
949                         hostdata->pendingw++;
950                         break;
951                 case READ:
952                 case READ_6:
953                 case READ_10:
954                         hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
955                         hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen;
956                         hostdata->pendingr++;
957                         break;
958                 }
959 #endif
960
961         /*
962          * We use the host_scribble field as a pointer to the next command
963          * in a queue
964          */
965
966         SET_NEXT(cmd, NULL);
967         cmd->scsi_done = done;
968
969         cmd->result = 0;
970
971         /*
972          * Insert the cmd into the issue queue. Note that REQUEST SENSE
973          * commands are added to the head of the queue since any command will
974          * clear the contingent allegiance condition that exists and the
975          * sense data is only guaranteed to be valid while the condition exists.
976          */
977
978         local_irq_save(flags);
979         /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
980          * Otherwise a running NCR5380_main may steal the lock.
981          * Lock before actually inserting due to fairness reasons explained in
982          * atari_scsi.c. If we insert first, then it's impossible for this driver
983          * to release the lock.
984          * Stop timer for this command while waiting for the lock, or timeouts
985          * may happen (and they really do), and it's no good if the command doesn't
986          * appear in any of the queues.
987          * ++roman: Just disabling the NCR interrupt isn't sufficient here,
988          * because also a timer int can trigger an abort or reset, which would
989          * alter queues and touch the lock.
990          */
991         if (!IS_A_TT()) {
992                 /* perhaps stop command timer here */
993                 falcon_get_lock();
994                 /* perhaps restart command timer here */
995         }
996         if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
997                 LIST(cmd, hostdata->issue_queue);
998                 SET_NEXT(cmd, hostdata->issue_queue);
999                 hostdata->issue_queue = cmd;
1000         } else {
1001                 for (tmp = (Scsi_Cmnd *)hostdata->issue_queue;
1002                      NEXT(tmp); tmp = NEXT(tmp))
1003                         ;
1004                 LIST(cmd, tmp);
1005                 SET_NEXT(tmp, cmd);
1006         }
1007         local_irq_restore(flags);
1008
1009         QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd),
1010                   (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
1011
1012         /* If queue_command() is called from an interrupt (real one or bottom
1013          * half), we let queue_main() do the job of taking care about main. If it
1014          * is already running, this is a no-op, else main will be queued.
1015          *
1016          * If we're not in an interrupt, we can call NCR5380_main()
1017          * unconditionally, because it cannot be already running.
1018          */
1019         if (in_interrupt() || ((flags >> 8) & 7) >= 6)
1020                 queue_main();
1021         else
1022                 NCR5380_main(NULL);
1023         return 0;
1024 }
1025
1026 /*
1027  * Function : NCR5380_main (void)
1028  *
1029  * Purpose : NCR5380_main is a coroutine that runs as long as more work can
1030  *      be done on the NCR5380 host adapters in a system.  Both
1031  *      NCR5380_queue_command() and NCR5380_intr() will try to start it
1032  *      in case it is not running.
1033  *
1034  * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
1035  *  reenable them.  This prevents reentrancy and kernel stack overflow.
1036  */
1037
1038 static void NCR5380_main(struct work_struct *work)
1039 {
1040         Scsi_Cmnd *tmp, *prev;
1041         struct Scsi_Host *instance = first_instance;
1042         struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
1043         int done;
1044         unsigned long flags;
1045
1046         /*
1047          * We run (with interrupts disabled) until we're sure that none of
1048          * the host adapters have anything that can be done, at which point
1049          * we set main_running to 0 and exit.
1050          *
1051          * Interrupts are enabled before doing various other internal
1052          * instructions, after we've decided that we need to run through
1053          * the loop again.
1054          *
1055          * this should prevent any race conditions.
1056          *
1057          * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1058          * because also a timer int can trigger an abort or reset, which can
1059          * alter queues and touch the Falcon lock.
1060          */
1061
1062         /* Tell int handlers main() is now already executing.  Note that
1063            no races are possible here. If an int comes in before
1064            'main_running' is set here, and queues/executes main via the
1065            task queue, it doesn't do any harm, just this instance of main
1066            won't find any work left to do. */
1067         if (main_running)
1068                 return;
1069         main_running = 1;
1070
1071         local_save_flags(flags);
1072         do {
1073                 local_irq_disable();    /* Freeze request queues */
1074                 done = 1;
1075
1076                 if (!hostdata->connected) {
1077                         MAIN_PRINTK("scsi%d: not connected\n", HOSTNO);
1078                         /*
1079                          * Search through the issue_queue for a command destined
1080                          * for a target that's not busy.
1081                          */
1082 #if (NDEBUG & NDEBUG_LISTS)
1083                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL;
1084                              tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
1085                                 ;
1086                         /*printk("%p  ", tmp);*/
1087                         if ((tmp == prev) && tmp)
1088                                 printk(" LOOP\n");
1089                         /* else printk("\n"); */
1090 #endif
1091                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue,
1092                              prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) {
1093
1094 #if (NDEBUG & NDEBUG_LISTS)
1095                                 if (prev != tmp)
1096                                         printk("MAIN tmp=%p   target=%d   busy=%d lun=%d\n",
1097                                                tmp, tmp->device->id, hostdata->busy[tmp->device->id],
1098                                                tmp->device->lun);
1099 #endif
1100                                 /*  When we find one, remove it from the issue queue. */
1101                                 /* ++guenther: possible race with Falcon locking */
1102                                 if (
1103 #ifdef SUPPORT_TAGS
1104                                     !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
1105 #else
1106                                     !(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))
1107 #endif
1108                                     ) {
1109                                         /* ++guenther: just to be sure, this must be atomic */
1110                                         local_irq_disable();
1111                                         if (prev) {
1112                                                 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1113                                                 SET_NEXT(prev, NEXT(tmp));
1114                                         } else {
1115                                                 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
1116                                                 hostdata->issue_queue = NEXT(tmp);
1117                                         }
1118                                         SET_NEXT(tmp, NULL);
1119                                         falcon_dont_release++;
1120
1121                                         /* reenable interrupts after finding one */
1122                                         local_irq_restore(flags);
1123
1124                                         /*
1125                                          * Attempt to establish an I_T_L nexus here.
1126                                          * On success, instance->hostdata->connected is set.
1127                                          * On failure, we must add the command back to the
1128                                          *   issue queue so we can keep trying.
1129                                          */
1130                                         MAIN_PRINTK("scsi%d: main(): command for target %d "
1131                                                     "lun %d removed from issue_queue\n",
1132                                                     HOSTNO, tmp->device->id, tmp->device->lun);
1133                                         /*
1134                                          * REQUEST SENSE commands are issued without tagged
1135                                          * queueing, even on SCSI-II devices because the
1136                                          * contingent allegiance condition exists for the
1137                                          * entire unit.
1138                                          */
1139                                         /* ++roman: ...and the standard also requires that
1140                                          * REQUEST SENSE command are untagged.
1141                                          */
1142
1143 #ifdef SUPPORT_TAGS
1144                                         cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE);
1145 #endif
1146                                         if (!NCR5380_select(instance, tmp,
1147                                             (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE :
1148                                             TAG_NEXT)) {
1149                                                 falcon_dont_release--;
1150                                                 /* release if target did not response! */
1151                                                 falcon_release_lock_if_possible(hostdata);
1152                                                 break;
1153                                         } else {
1154                                                 local_irq_disable();
1155                                                 LIST(tmp, hostdata->issue_queue);
1156                                                 SET_NEXT(tmp, hostdata->issue_queue);
1157                                                 hostdata->issue_queue = tmp;
1158 #ifdef SUPPORT_TAGS
1159                                                 cmd_free_tag(tmp);
1160 #endif
1161                                                 falcon_dont_release--;
1162                                                 local_irq_restore(flags);
1163                                                 MAIN_PRINTK("scsi%d: main(): select() failed, "
1164                                                             "returned to issue_queue\n", HOSTNO);
1165                                                 if (hostdata->connected)
1166                                                         break;
1167                                         }
1168                                 } /* if target/lun/target queue is not busy */
1169                         } /* for issue_queue */
1170                 } /* if (!hostdata->connected) */
1171
1172                 if (hostdata->connected
1173 #ifdef REAL_DMA
1174                     && !hostdata->dma_len
1175 #endif
1176                     ) {
1177                         local_irq_restore(flags);
1178                         MAIN_PRINTK("scsi%d: main: performing information transfer\n",
1179                                     HOSTNO);
1180                         NCR5380_information_transfer(instance);
1181                         MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO);
1182                         done = 0;
1183                 }
1184         } while (!done);
1185
1186         /* Better allow ints _after_ 'main_running' has been cleared, else
1187            an interrupt could believe we'll pick up the work it left for
1188            us, but we won't see it anymore here... */
1189         main_running = 0;
1190         local_irq_restore(flags);
1191 }
1192
1193
1194 #ifdef REAL_DMA
1195 /*
1196  * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1197  *
1198  * Purpose : Called by interrupt handler when DMA finishes or a phase
1199  *      mismatch occurs (which would finish the DMA transfer).
1200  *
1201  * Inputs : instance - this instance of the NCR5380.
1202  *
1203  */
1204
1205 static void NCR5380_dma_complete(struct Scsi_Host *instance)
1206 {
1207         SETUP_HOSTDATA(instance);
1208         int transfered, saved_data = 0, overrun = 0, cnt, toPIO;
1209         unsigned char **data, p;
1210         volatile int *count;
1211
1212         if (!hostdata->connected) {
1213                 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
1214                        "no connected cmd\n", HOSTNO);
1215                 return;
1216         }
1217
1218         if (atari_read_overruns) {
1219                 p = hostdata->connected->SCp.phase;
1220                 if (p & SR_IO) {
1221                         udelay(10);
1222                         if ((NCR5380_read(BUS_AND_STATUS_REG) &
1223                              (BASR_PHASE_MATCH|BASR_ACK)) ==
1224                             (BASR_PHASE_MATCH|BASR_ACK)) {
1225                                 saved_data = NCR5380_read(INPUT_DATA_REG);
1226                                 overrun = 1;
1227                                 DMA_PRINTK("scsi%d: read overrun handled\n", HOSTNO);
1228                         }
1229                 }
1230         }
1231
1232         DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1233                    HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
1234                    NCR5380_read(STATUS_REG));
1235
1236         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1237         NCR5380_write(MODE_REG, MR_BASE);
1238         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1239
1240         transfered = hostdata->dma_len - NCR5380_dma_residual(instance);
1241         hostdata->dma_len = 0;
1242
1243         data = (unsigned char **)&hostdata->connected->SCp.ptr;
1244         count = &hostdata->connected->SCp.this_residual;
1245         *data += transfered;
1246         *count -= transfered;
1247
1248         if (atari_read_overruns) {
1249                 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
1250                         cnt = toPIO = atari_read_overruns;
1251                         if (overrun) {
1252                                 DMA_PRINTK("Got an input overrun, using saved byte\n");
1253                                 *(*data)++ = saved_data;
1254                                 (*count)--;
1255                                 cnt--;
1256                                 toPIO--;
1257                         }
1258                         DMA_PRINTK("Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
1259                         NCR5380_transfer_pio(instance, &p, &cnt, data);
1260                         *count -= toPIO - cnt;
1261                 }
1262         }
1263 }
1264 #endif /* REAL_DMA */
1265
1266
1267 /*
1268  * Function : void NCR5380_intr (int irq)
1269  *
1270  * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1271  *      from the disconnected queue, and restarting NCR5380_main()
1272  *      as required.
1273  *
1274  * Inputs : int irq, irq that caused this interrupt.
1275  *
1276  */
1277
1278 static irqreturn_t NCR5380_intr(int irq, void *dev_id)
1279 {
1280         struct Scsi_Host *instance = first_instance;
1281         int done = 1, handled = 0;
1282         unsigned char basr;
1283
1284         INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO);
1285
1286         /* Look for pending interrupts */
1287         basr = NCR5380_read(BUS_AND_STATUS_REG);
1288         INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr);
1289         /* dispatch to appropriate routine if found and done=0 */
1290         if (basr & BASR_IRQ) {
1291                 NCR_PRINT(NDEBUG_INTR);
1292                 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
1293                         done = 0;
1294                         ENABLE_IRQ();
1295                         INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO);
1296                         NCR5380_reselect(instance);
1297                         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1298                 } else if (basr & BASR_PARITY_ERROR) {
1299                         INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO);
1300                         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1301                 } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1302                         INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO);
1303                         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1304                 } else {
1305                         /*
1306                          * The rest of the interrupt conditions can occur only during a
1307                          * DMA transfer
1308                          */
1309
1310 #if defined(REAL_DMA)
1311                         /*
1312                          * We should only get PHASE MISMATCH and EOP interrupts if we have
1313                          * DMA enabled, so do a sanity check based on the current setting
1314                          * of the MODE register.
1315                          */
1316
1317                         if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
1318                             ((basr & BASR_END_DMA_TRANSFER) ||
1319                              !(basr & BASR_PHASE_MATCH))) {
1320
1321                                 INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1322                                 NCR5380_dma_complete( instance );
1323                                 done = 0;
1324                                 ENABLE_IRQ();
1325                         } else
1326 #endif /* REAL_DMA */
1327                         {
1328 /* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1329                                 if (basr & BASR_PHASE_MATCH)
1330                                         printk(KERN_NOTICE "scsi%d: unknown interrupt, "
1331                                                "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1332                                                HOSTNO, basr, NCR5380_read(MODE_REG),
1333                                                NCR5380_read(STATUS_REG));
1334                                 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1335                         }
1336                 } /* if !(SELECTION || PARITY) */
1337                 handled = 1;
1338         } /* BASR & IRQ */ else {
1339                 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
1340                        "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
1341                        NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG));
1342                 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1343         }
1344
1345         if (!done) {
1346                 INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO);
1347                 /* Put a call to NCR5380_main() on the queue... */
1348                 queue_main();
1349         }
1350         return IRQ_RETVAL(handled);
1351 }
1352
1353 #ifdef NCR5380_STATS
1354 static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd *cmd)
1355 {
1356 # ifdef NCR5380_STAT_LIMIT
1357         if (cmd->request_bufflen > NCR5380_STAT_LIMIT)
1358 # endif
1359                 switch (cmd->cmnd[0]) {
1360                 case WRITE:
1361                 case WRITE_6:
1362                 case WRITE_10:
1363                         hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase);
1364                         /*hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen;*/
1365                         hostdata->pendingw--;
1366                         break;
1367                 case READ:
1368                 case READ_6:
1369                 case READ_10:
1370                         hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase);
1371                         /*hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen;*/
1372                         hostdata->pendingr--;
1373                         break;
1374                 }
1375 }
1376 #endif
1377
1378 /*
1379  * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1380  *      int tag);
1381  *
1382  * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1383  *      including ARBITRATION, SELECTION, and initial message out for
1384  *      IDENTIFY and queue messages.
1385  *
1386  * Inputs : instance - instantiation of the 5380 driver on which this
1387  *      target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1388  *      new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1389  *      the command that is presently connected.
1390  *
1391  * Returns : -1 if selection could not execute for some reason,
1392  *      0 if selection succeeded or failed because the target
1393  *      did not respond.
1394  *
1395  * Side effects :
1396  *      If bus busy, arbitration failed, etc, NCR5380_select() will exit
1397  *              with registers as they should have been on entry - ie
1398  *              SELECT_ENABLE will be set appropriately, the NCR5380
1399  *              will cease to drive any SCSI bus signals.
1400  *
1401  *      If successful : I_T_L or I_T_L_Q nexus will be established,
1402  *              instance->connected will be set to cmd.
1403  *              SELECT interrupt will be disabled.
1404  *
1405  *      If failed (no target) : cmd->scsi_done() will be called, and the
1406  *              cmd->result host byte set to DID_BAD_TARGET.
1407  */
1408
1409 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag)
1410 {
1411         SETUP_HOSTDATA(instance);
1412         unsigned char tmp[3], phase;
1413         unsigned char *data;
1414         int len;
1415         unsigned long timeout;
1416         unsigned long flags;
1417
1418         hostdata->restart_select = 0;
1419         NCR_PRINT(NDEBUG_ARBITRATION);
1420         ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO,
1421                    instance->this_id);
1422
1423         /*
1424          * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1425          * data bus during SELECTION.
1426          */
1427
1428         local_irq_save(flags);
1429         if (hostdata->connected) {
1430                 local_irq_restore(flags);
1431                 return -1;
1432         }
1433         NCR5380_write(TARGET_COMMAND_REG, 0);
1434
1435         /*
1436          * Start arbitration.
1437          */
1438
1439         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1440         NCR5380_write(MODE_REG, MR_ARBITRATE);
1441
1442         local_irq_restore(flags);
1443
1444         /* Wait for arbitration logic to complete */
1445 #if defined(NCR_TIMEOUT)
1446         {
1447                 unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
1448
1449                 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
1450                        time_before(jiffies, timeout) && !hostdata->connected)
1451                         ;
1452                 if (time_after_eq(jiffies, timeout)) {
1453                         printk("scsi : arbitration timeout at %d\n", __LINE__);
1454                         NCR5380_write(MODE_REG, MR_BASE);
1455                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1456                         return -1;
1457                 }
1458         }
1459 #else /* NCR_TIMEOUT */
1460         while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
1461                !hostdata->connected)
1462                 ;
1463 #endif
1464
1465         ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO);
1466
1467         if (hostdata->connected) {
1468                 NCR5380_write(MODE_REG, MR_BASE);
1469                 return -1;
1470         }
1471         /*
1472          * The arbitration delay is 2.2us, but this is a minimum and there is
1473          * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1474          * the integral nature of udelay().
1475          *
1476          */
1477
1478         udelay(3);
1479
1480         /* Check for lost arbitration */
1481         if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1482             (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
1483             (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1484             hostdata->connected) {
1485                 NCR5380_write(MODE_REG, MR_BASE);
1486                 ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1487                            HOSTNO);
1488                 return -1;
1489         }
1490
1491         /* after/during arbitration, BSY should be asserted.
1492            IBM DPES-31080 Version S31Q works now */
1493         /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
1494         NCR5380_write(INITIATOR_COMMAND_REG,
1495                       ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY);
1496
1497         if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1498             hostdata->connected) {
1499                 NCR5380_write(MODE_REG, MR_BASE);
1500                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1501                 ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1502                            HOSTNO);
1503                 return -1;
1504         }
1505
1506         /*
1507          * Again, bus clear + bus settle time is 1.2us, however, this is
1508          * a minimum so we'll udelay ceil(1.2)
1509          */
1510
1511 #ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1512         /* ++roman: But some targets (see above :-) seem to need a bit more... */
1513         udelay(15);
1514 #else
1515         udelay(2);
1516 #endif
1517
1518         if (hostdata->connected) {
1519                 NCR5380_write(MODE_REG, MR_BASE);
1520                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1521                 return -1;
1522         }
1523
1524         ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO);
1525
1526         /*
1527          * Now that we have won arbitration, start Selection process, asserting
1528          * the host and target ID's on the SCSI bus.
1529          */
1530
1531         NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id)));
1532
1533         /*
1534          * Raise ATN while SEL is true before BSY goes false from arbitration,
1535          * since this is the only way to guarantee that we'll get a MESSAGE OUT
1536          * phase immediately after selection.
1537          */
1538
1539         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY |
1540                       ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL ));
1541         NCR5380_write(MODE_REG, MR_BASE);
1542
1543         /*
1544          * Reselect interrupts must be turned off prior to the dropping of BSY,
1545          * otherwise we will trigger an interrupt.
1546          */
1547
1548         if (hostdata->connected) {
1549                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1550                 return -1;
1551         }
1552
1553         NCR5380_write(SELECT_ENABLE_REG, 0);
1554
1555         /*
1556          * The initiator shall then wait at least two deskew delays and release
1557          * the BSY signal.
1558          */
1559         udelay(1);        /* wingel -- wait two bus deskew delay >2*45ns */
1560
1561         /* Reset BSY */
1562         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA |
1563                       ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1564
1565         /*
1566          * Something weird happens when we cease to drive BSY - looks
1567          * like the board/chip is letting us do another read before the
1568          * appropriate propagation delay has expired, and we're confusing
1569          * a BSY signal from ourselves as the target's response to SELECTION.
1570          *
1571          * A small delay (the 'C++' frontend breaks the pipeline with an
1572          * unnecessary jump, making it work on my 386-33/Trantor T128, the
1573          * tighter 'C' code breaks and requires this) solves the problem -
1574          * the 1 us delay is arbitrary, and only used because this delay will
1575          * be the same on other platforms and since it works here, it should
1576          * work there.
1577          *
1578          * wingel suggests that this could be due to failing to wait
1579          * one deskew delay.
1580          */
1581
1582         udelay(1);
1583
1584         SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
1585
1586         /*
1587          * The SCSI specification calls for a 250 ms timeout for the actual
1588          * selection.
1589          */
1590
1591         timeout = jiffies + 25;
1592
1593         /*
1594          * XXX very interesting - we're seeing a bounce where the BSY we
1595          * asserted is being reflected / still asserted (propagation delay?)
1596          * and it's detecting as true.  Sigh.
1597          */
1598
1599 #if 0
1600         /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1601          * IO while SEL is true. But again, there are some disks out the in the
1602          * world that do that nevertheless. (Somebody claimed that this announces
1603          * reselection capability of the target.) So we better skip that test and
1604          * only wait for BSY... (Famous german words: Der Kl├╝gere gibt nach :-)
1605          */
1606
1607         while (time_before(jiffies, timeout) &&
1608                !(NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO)))
1609                 ;
1610
1611         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1612                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1613                 NCR5380_reselect(instance);
1614                 printk(KERN_ERR "scsi%d: reselection after won arbitration?\n",
1615                        HOSTNO);
1616                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1617                 return -1;
1618         }
1619 #else
1620         while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY))
1621                 ;
1622 #endif
1623
1624         /*
1625          * No less than two deskew delays after the initiator detects the
1626          * BSY signal is true, it shall release the SEL signal and may
1627          * change the DATA BUS.                                     -wingel
1628          */
1629
1630         udelay(1);
1631
1632         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1633
1634         if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1635                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1636                 if (hostdata->targets_present & (1 << cmd->device->id)) {
1637                         printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO);
1638                         if (hostdata->restart_select)
1639                                 printk(KERN_NOTICE "\trestart select\n");
1640                         NCR_PRINT(NDEBUG_ANY);
1641                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1642                         return -1;
1643                 }
1644                 cmd->result = DID_BAD_TARGET << 16;
1645 #ifdef NCR5380_STATS
1646                 collect_stats(hostdata, cmd);
1647 #endif
1648 #ifdef SUPPORT_TAGS
1649                 cmd_free_tag(cmd);
1650 #endif
1651                 cmd->scsi_done(cmd);
1652                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1653                 SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO);
1654                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1655                 return 0;
1656         }
1657
1658         hostdata->targets_present |= (1 << cmd->device->id);
1659
1660         /*
1661          * Since we followed the SCSI spec, and raised ATN while SEL
1662          * was true but before BSY was false during selection, the information
1663          * transfer phase should be a MESSAGE OUT phase so that we can send the
1664          * IDENTIFY message.
1665          *
1666          * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1667          * message (2 bytes) with a tag ID that we increment with every command
1668          * until it wraps back to 0.
1669          *
1670          * XXX - it turns out that there are some broken SCSI-II devices,
1671          *           which claim to support tagged queuing but fail when more than
1672          *           some number of commands are issued at once.
1673          */
1674
1675         /* Wait for start of REQ/ACK handshake */
1676         while (!(NCR5380_read(STATUS_REG) & SR_REQ))
1677                 ;
1678
1679         SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1680                    HOSTNO, cmd->device->id);
1681         tmp[0] = IDENTIFY(1, cmd->device->lun);
1682
1683 #ifdef SUPPORT_TAGS
1684         if (cmd->tag != TAG_NONE) {
1685                 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
1686                 tmp[2] = cmd->tag;
1687                 len = 3;
1688         } else
1689                 len = 1;
1690 #else
1691         len = 1;
1692         cmd->tag = 0;
1693 #endif /* SUPPORT_TAGS */
1694
1695         /* Send message(s) */
1696         data = tmp;
1697         phase = PHASE_MSGOUT;
1698         NCR5380_transfer_pio(instance, &phase, &len, &data);
1699         SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO);
1700         /* XXX need to handle errors here */
1701         hostdata->connected = cmd;
1702 #ifndef SUPPORT_TAGS
1703         hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1704 #endif
1705
1706         initialize_SCp(cmd);
1707
1708         return 0;
1709 }
1710
1711 /*
1712  * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1713  *      unsigned char *phase, int *count, unsigned char **data)
1714  *
1715  * Purpose : transfers data in given phase using polled I/O
1716  *
1717  * Inputs : instance - instance of driver, *phase - pointer to
1718  *      what phase is expected, *count - pointer to number of
1719  *      bytes to transfer, **data - pointer to data pointer.
1720  *
1721  * Returns : -1 when different phase is entered without transferring
1722  *      maximum number of bytes, 0 if all bytes are transfered or exit
1723  *      is in same phase.
1724  *
1725  *      Also, *phase, *count, *data are modified in place.
1726  *
1727  * XXX Note : handling for bus free may be useful.
1728  */
1729
1730 /*
1731  * Note : this code is not as quick as it could be, however it
1732  * IS 100% reliable, and for the actual data transfer where speed
1733  * counts, we will always do a pseudo DMA or DMA transfer.
1734  */
1735
1736 static int NCR5380_transfer_pio(struct Scsi_Host *instance,
1737                                 unsigned char *phase, int *count,
1738                                 unsigned char **data)
1739 {
1740         register unsigned char p = *phase, tmp;
1741         register int c = *count;
1742         register unsigned char *d = *data;
1743
1744         /*
1745          * The NCR5380 chip will only drive the SCSI bus when the
1746          * phase specified in the appropriate bits of the TARGET COMMAND
1747          * REGISTER match the STATUS REGISTER
1748          */
1749
1750         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1751
1752         do {
1753                 /*
1754                  * Wait for assertion of REQ, after which the phase bits will be
1755                  * valid
1756                  */
1757                 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1758                         ;
1759
1760                 HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO);
1761
1762                 /* Check for phase mismatch */
1763                 if ((tmp & PHASE_MASK) != p) {
1764                         PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO);
1765                         NCR_PRINT_PHASE(NDEBUG_PIO);
1766                         break;
1767                 }
1768
1769                 /* Do actual transfer from SCSI bus to / from memory */
1770                 if (!(p & SR_IO))
1771                         NCR5380_write(OUTPUT_DATA_REG, *d);
1772                 else
1773                         *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1774
1775                 ++d;
1776
1777                 /*
1778                  * The SCSI standard suggests that in MSGOUT phase, the initiator
1779                  * should drop ATN on the last byte of the message phase
1780                  * after REQ has been asserted for the handshake but before
1781                  * the initiator raises ACK.
1782                  */
1783
1784                 if (!(p & SR_IO)) {
1785                         if (!((p & SR_MSG) && c > 1)) {
1786                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1787                                 NCR_PRINT(NDEBUG_PIO);
1788                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1789                                               ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1790                         } else {
1791                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1792                                               ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1793                                 NCR_PRINT(NDEBUG_PIO);
1794                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1795                                               ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1796                         }
1797                 } else {
1798                         NCR_PRINT(NDEBUG_PIO);
1799                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1800                 }
1801
1802                 while (NCR5380_read(STATUS_REG) & SR_REQ)
1803                         ;
1804
1805                 HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO);
1806
1807                 /*
1808                  * We have several special cases to consider during REQ/ACK handshaking :
1809                  * 1.  We were in MSGOUT phase, and we are on the last byte of the
1810                  *      message.  ATN must be dropped as ACK is dropped.
1811                  *
1812                  * 2.  We are in a MSGIN phase, and we are on the last byte of the
1813                  *      message.  We must exit with ACK asserted, so that the calling
1814                  *      code may raise ATN before dropping ACK to reject the message.
1815                  *
1816                  * 3.  ACK and ATN are clear and the target may proceed as normal.
1817                  */
1818                 if (!(p == PHASE_MSGIN && c == 1)) {
1819                         if (p == PHASE_MSGOUT && c > 1)
1820                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1821                         else
1822                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1823                 }
1824         } while (--c);
1825
1826         PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c);
1827
1828         *count = c;
1829         *data = d;
1830         tmp = NCR5380_read(STATUS_REG);
1831         /* The phase read from the bus is valid if either REQ is (already)
1832          * asserted or if ACK hasn't been released yet. The latter is the case if
1833          * we're in MSGIN and all wanted bytes have been received.
1834          */
1835         if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
1836                 *phase = tmp & PHASE_MASK;
1837         else
1838                 *phase = PHASE_UNKNOWN;
1839
1840         if (!c || (*phase == p))
1841                 return 0;
1842         else
1843                 return -1;
1844 }
1845
1846 /*
1847  * Function : do_abort (Scsi_Host *host)
1848  *
1849  * Purpose : abort the currently established nexus.  Should only be
1850  *      called from a routine which can drop into a
1851  *
1852  * Returns : 0 on success, -1 on failure.
1853  */
1854
1855 static int do_abort(struct Scsi_Host *host)
1856 {
1857         unsigned char tmp, *msgptr, phase;
1858         int len;
1859
1860         /* Request message out phase */
1861         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1862
1863         /*
1864          * Wait for the target to indicate a valid phase by asserting
1865          * REQ.  Once this happens, we'll have either a MSGOUT phase
1866          * and can immediately send the ABORT message, or we'll have some
1867          * other phase and will have to source/sink data.
1868          *
1869          * We really don't care what value was on the bus or what value
1870          * the target sees, so we just handshake.
1871          */
1872
1873         while (!(tmp = NCR5380_read(STATUS_REG)) & SR_REQ)
1874                 ;
1875
1876         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1877
1878         if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1879                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
1880                               ICR_ASSERT_ACK);
1881                 while (NCR5380_read(STATUS_REG) & SR_REQ)
1882                         ;
1883                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1884         }
1885
1886         tmp = ABORT;
1887         msgptr = &tmp;
1888         len = 1;
1889         phase = PHASE_MSGOUT;
1890         NCR5380_transfer_pio(host, &phase, &len, &msgptr);
1891
1892         /*
1893          * If we got here, and the command completed successfully,
1894          * we're about to go into bus free state.
1895          */
1896
1897         return len ? -1 : 0;
1898 }
1899
1900 #if defined(REAL_DMA)
1901 /*
1902  * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1903  *      unsigned char *phase, int *count, unsigned char **data)
1904  *
1905  * Purpose : transfers data in given phase using either real
1906  *      or pseudo DMA.
1907  *
1908  * Inputs : instance - instance of driver, *phase - pointer to
1909  *      what phase is expected, *count - pointer to number of
1910  *      bytes to transfer, **data - pointer to data pointer.
1911  *
1912  * Returns : -1 when different phase is entered without transferring
1913  *      maximum number of bytes, 0 if all bytes or transfered or exit
1914  *      is in same phase.
1915  *
1916  *      Also, *phase, *count, *data are modified in place.
1917  *
1918  */
1919
1920
1921 static int NCR5380_transfer_dma(struct Scsi_Host *instance,
1922                                 unsigned char *phase, int *count,
1923                                 unsigned char **data)
1924 {
1925         SETUP_HOSTDATA(instance);
1926         register int c = *count;
1927         register unsigned char p = *phase;
1928         register unsigned char *d = *data;
1929         unsigned char tmp;
1930         unsigned long flags;
1931
1932         if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1933                 *phase = tmp;
1934                 return -1;
1935         }
1936
1937         if (atari_read_overruns && (p & SR_IO))
1938                 c -= atari_read_overruns;
1939
1940         DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1941                    HOSTNO, (p & SR_IO) ? "reading" : "writing",
1942                    c, (p & SR_IO) ? "to" : "from", d);
1943
1944         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1945
1946 #ifdef REAL_DMA
1947         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1948 #endif /* def REAL_DMA  */
1949
1950         if (IS_A_TT()) {
1951                 /* On the Medusa, it is a must to initialize the DMA before
1952                  * starting the NCR. This is also the cleaner way for the TT.
1953                  */
1954                 local_irq_save(flags);
1955                 hostdata->dma_len = (p & SR_IO) ?
1956                         NCR5380_dma_read_setup(instance, d, c) :
1957                         NCR5380_dma_write_setup(instance, d, c);
1958                 local_irq_restore(flags);
1959         }
1960
1961         if (p & SR_IO)
1962                 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1963         else {
1964                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1965                 NCR5380_write(START_DMA_SEND_REG, 0);
1966         }
1967
1968         if (!IS_A_TT()) {
1969                 /* On the Falcon, the DMA setup must be done after the last */
1970                 /* NCR access, else the DMA setup gets trashed!
1971                  */
1972                 local_irq_save(flags);
1973                 hostdata->dma_len = (p & SR_IO) ?
1974                         NCR5380_dma_read_setup(instance, d, c) :
1975                         NCR5380_dma_write_setup(instance, d, c);
1976                 local_irq_restore(flags);
1977         }
1978         return 0;
1979 }
1980 #endif /* defined(REAL_DMA) */
1981
1982 /*
1983  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1984  *
1985  * Purpose : run through the various SCSI phases and do as the target
1986  *      directs us to.  Operates on the currently connected command,
1987  *      instance->connected.
1988  *
1989  * Inputs : instance, instance for which we are doing commands
1990  *
1991  * Side effects : SCSI things happen, the disconnected queue will be
1992  *      modified if a command disconnects, *instance->connected will
1993  *      change.
1994  *
1995  * XXX Note : we need to watch for bus free or a reset condition here
1996  *      to recover from an unexpected bus free condition.
1997  */
1998
1999 static void NCR5380_information_transfer(struct Scsi_Host *instance)
2000 {
2001         SETUP_HOSTDATA(instance);
2002         unsigned long flags;
2003         unsigned char msgout = NOP;
2004         int sink = 0;
2005         int len;
2006 #if defined(REAL_DMA)
2007         int transfersize;
2008 #endif
2009         unsigned char *data;
2010         unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2011         Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2012
2013         while (1) {
2014                 tmp = NCR5380_read(STATUS_REG);
2015                 /* We only have a valid SCSI phase when REQ is asserted */
2016                 if (tmp & SR_REQ) {
2017                         phase = (tmp & PHASE_MASK);
2018                         if (phase != old_phase) {
2019                                 old_phase = phase;
2020                                 NCR_PRINT_PHASE(NDEBUG_INFORMATION);
2021                         }
2022
2023                         if (sink && (phase != PHASE_MSGOUT)) {
2024                                 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2025
2026                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
2027                                               ICR_ASSERT_ACK);
2028                                 while (NCR5380_read(STATUS_REG) & SR_REQ)
2029                                         ;
2030                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2031                                               ICR_ASSERT_ATN);
2032                                 sink = 0;
2033                                 continue;
2034                         }
2035
2036                         switch (phase) {
2037                         case PHASE_DATAOUT:
2038 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2039                                 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2040                                        "aborted\n", HOSTNO);
2041                                 sink = 1;
2042                                 do_abort(instance);
2043                                 cmd->result = DID_ERROR << 16;
2044                                 cmd->scsi_done(cmd);
2045                                 return;
2046 #endif
2047                         case PHASE_DATAIN:
2048                                 /*
2049                                  * If there is no room left in the current buffer in the
2050                                  * scatter-gather list, move onto the next one.
2051                                  */
2052
2053                                 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2054                                         ++cmd->SCp.buffer;
2055                                         --cmd->SCp.buffers_residual;
2056                                         cmd->SCp.this_residual = cmd->SCp.buffer->length;
2057                                         cmd->SCp.ptr = page_address(cmd->SCp.buffer->page) +
2058                                                    cmd->SCp.buffer->offset;
2059                                         /* ++roman: Try to merge some scatter-buffers if
2060                                          * they are at contiguous physical addresses.
2061                                          */
2062                                         merge_contiguous_buffers(cmd);
2063                                         INF_PRINTK("scsi%d: %d bytes and %d buffers left\n",
2064                                                    HOSTNO, cmd->SCp.this_residual,
2065                                                    cmd->SCp.buffers_residual);
2066                                 }
2067
2068                                 /*
2069                                  * The preferred transfer method is going to be
2070                                  * PSEUDO-DMA for systems that are strictly PIO,
2071                                  * since we can let the hardware do the handshaking.
2072                                  *
2073                                  * For this to work, we need to know the transfersize
2074                                  * ahead of time, since the pseudo-DMA code will sit
2075                                  * in an unconditional loop.
2076                                  */
2077
2078                                 /* ++roman: I suggest, this should be
2079                                  *   #if def(REAL_DMA)
2080                                  * instead of leaving REAL_DMA out.
2081                                  */
2082
2083 #if defined(REAL_DMA)
2084                                 if (!cmd->device->borken &&
2085                                     (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) {
2086                                         len = transfersize;
2087                                         cmd->SCp.phase = phase;
2088                                         if (NCR5380_transfer_dma(instance, &phase,
2089                                             &len, (unsigned char **)&cmd->SCp.ptr)) {
2090                                                 /*
2091                                                  * If the watchdog timer fires, all future
2092                                                  * accesses to this device will use the
2093                                                  * polled-IO. */
2094                                                 printk(KERN_NOTICE "scsi%d: switching target %d "
2095                                                            "lun %d to slow handshake\n", HOSTNO,
2096                                                            cmd->device->id, cmd->device->lun);
2097                                                 cmd->device->borken = 1;
2098                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2099                                                         ICR_ASSERT_ATN);
2100                                                 sink = 1;
2101                                                 do_abort(instance);
2102                                                 cmd->result = DID_ERROR << 16;
2103                                                 cmd->scsi_done(cmd);
2104                                                 /* XXX - need to source or sink data here, as appropriate */
2105                                         } else {
2106 #ifdef REAL_DMA
2107                                                 /* ++roman: When using real DMA,
2108                                                  * information_transfer() should return after
2109                                                  * starting DMA since it has nothing more to
2110                                                  * do.
2111                                                  */
2112                                                 return;
2113 #else
2114                                                 cmd->SCp.this_residual -= transfersize - len;
2115 #endif
2116                                         }
2117                                 } else
2118 #endif /* defined(REAL_DMA) */
2119                                         NCR5380_transfer_pio(instance, &phase,
2120                                                              (int *)&cmd->SCp.this_residual,
2121                                                              (unsigned char **)&cmd->SCp.ptr);
2122                                 break;
2123                         case PHASE_MSGIN:
2124                                 len = 1;
2125                                 data = &tmp;
2126                                 NCR5380_write(SELECT_ENABLE_REG, 0);    /* disable reselects */
2127                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2128                                 cmd->SCp.Message = tmp;
2129
2130                                 switch (tmp) {
2131                                 /*
2132                                  * Linking lets us reduce the time required to get the
2133                                  * next command out to the device, hopefully this will
2134                                  * mean we don't waste another revolution due to the delays
2135                                  * required by ARBITRATION and another SELECTION.
2136                                  *
2137                                  * In the current implementation proposal, low level drivers
2138                                  * merely have to start the next command, pointed to by
2139                                  * next_link, done() is called as with unlinked commands.
2140                                  */
2141 #ifdef LINKED
2142                                 case LINKED_CMD_COMPLETE:
2143                                 case LINKED_FLG_CMD_COMPLETE:
2144                                         /* Accept message by clearing ACK */
2145                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2146
2147                                         LNK_PRINTK("scsi%d: target %d lun %d linked command "
2148                                                    "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun);
2149
2150                                         /* Enable reselect interrupts */
2151                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2152                                         /*
2153                                          * Sanity check : A linked command should only terminate
2154                                          * with one of these messages if there are more linked
2155                                          * commands available.
2156                                          */
2157
2158                                         if (!cmd->next_link) {
2159                                                  printk(KERN_NOTICE "scsi%d: target %d lun %d "
2160                                                         "linked command complete, no next_link\n",
2161                                                         HOSTNO, cmd->device->id, cmd->device->lun);
2162                                                 sink = 1;
2163                                                 do_abort(instance);
2164                                                 return;
2165                                         }
2166
2167                                         initialize_SCp(cmd->next_link);
2168                                         /* The next command is still part of this process; copy it
2169                                          * and don't free it! */
2170                                         cmd->next_link->tag = cmd->tag;
2171                                         cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2172                                         LNK_PRINTK("scsi%d: target %d lun %d linked request "
2173                                                    "done, calling scsi_done().\n",
2174                                                    HOSTNO, cmd->device->id, cmd->device->lun);
2175 #ifdef NCR5380_STATS
2176                                         collect_stats(hostdata, cmd);
2177 #endif
2178                                         cmd->scsi_done(cmd);
2179                                         cmd = hostdata->connected;
2180                                         break;
2181 #endif /* def LINKED */
2182                                 case ABORT:
2183                                 case COMMAND_COMPLETE:
2184                                         /* Accept message by clearing ACK */
2185                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2186                                         /* ++guenther: possible race with Falcon locking */
2187                                         falcon_dont_release++;
2188                                         hostdata->connected = NULL;
2189                                         QU_PRINTK("scsi%d: command for target %d, lun %d "
2190                                                   "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
2191 #ifdef SUPPORT_TAGS
2192                                         cmd_free_tag(cmd);
2193                                         if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
2194                                                 /* Turn a QUEUE FULL status into BUSY, I think the
2195                                                  * mid level cannot handle QUEUE FULL :-( (The
2196                                                  * command is retried after BUSY). Also update our
2197                                                  * queue size to the number of currently issued
2198                                                  * commands now.
2199                                                  */
2200                                                 /* ++Andreas: the mid level code knows about
2201                                                    QUEUE_FULL now. */
2202                                                 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
2203                                                 TAG_PRINTK("scsi%d: target %d lun %d returned "
2204                                                            "QUEUE_FULL after %d commands\n",
2205                                                            HOSTNO, cmd->device->id, cmd->device->lun,
2206                                                            ta->nr_allocated);
2207                                                 if (ta->queue_size > ta->nr_allocated)
2208                                                         ta->nr_allocated = ta->queue_size;
2209                                         }
2210 #else
2211                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2212 #endif
2213                                         /* Enable reselect interrupts */
2214                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2215
2216                                         /*
2217                                          * I'm not sure what the correct thing to do here is :
2218                                          *
2219                                          * If the command that just executed is NOT a request
2220                                          * sense, the obvious thing to do is to set the result
2221                                          * code to the values of the stored parameters.
2222                                          *
2223                                          * If it was a REQUEST SENSE command, we need some way to
2224                                          * differentiate between the failure code of the original
2225                                          * and the failure code of the REQUEST sense - the obvious
2226                                          * case is success, where we fall through and leave the
2227                                          * result code unchanged.
2228                                          *
2229                                          * The non-obvious place is where the REQUEST SENSE failed
2230                                          */
2231
2232                                         if (cmd->cmnd[0] != REQUEST_SENSE)
2233                                                 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2234                                         else if (status_byte(cmd->SCp.Status) != GOOD)
2235                                                 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2236
2237 #ifdef AUTOSENSE
2238                                         if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2239                                                 hostdata->ses.cmd_len) {
2240                                                 scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2241                                                 hostdata->ses.cmd_len = 0 ;
2242                                         }
2243
2244                                         if ((cmd->cmnd[0] != REQUEST_SENSE) &&
2245                                             (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2246                                                 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2247
2248                                                 ASEN_PRINTK("scsi%d: performing request sense\n", HOSTNO);
2249
2250                                                 local_irq_save(flags);
2251                                                 LIST(cmd,hostdata->issue_queue);
2252                                                 SET_NEXT(cmd, hostdata->issue_queue);
2253                                                 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2254                                                 local_irq_restore(flags);
2255                                                 QU_PRINTK("scsi%d: REQUEST SENSE added to head of "
2256                                                           "issue queue\n", H_NO(cmd));
2257                                         } else
2258 #endif /* def AUTOSENSE */
2259                                         {
2260 #ifdef NCR5380_STATS
2261                                                 collect_stats(hostdata, cmd);
2262 #endif
2263                                                 cmd->scsi_done(cmd);
2264                                         }
2265
2266                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2267                                         /*
2268                                          * Restore phase bits to 0 so an interrupted selection,
2269                                          * arbitration can resume.
2270                                          */
2271                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2272
2273                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2274                                                 barrier();
2275
2276                                         falcon_dont_release--;
2277                                         /* ++roman: For Falcon SCSI, release the lock on the
2278                                          * ST-DMA here if no other commands are waiting on the
2279                                          * disconnected queue.
2280                                          */
2281                                         falcon_release_lock_if_possible(hostdata);
2282                                         return;
2283                                 case MESSAGE_REJECT:
2284                                         /* Accept message by clearing ACK */
2285                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2286                                         /* Enable reselect interrupts */
2287                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2288                                         switch (hostdata->last_message) {
2289                                         case HEAD_OF_QUEUE_TAG:
2290                                         case ORDERED_QUEUE_TAG:
2291                                         case SIMPLE_QUEUE_TAG:
2292                                                 /* The target obviously doesn't support tagged
2293                                                  * queuing, even though it announced this ability in
2294                                                  * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2295                                                  * clear 'tagged_supported' and lock the LUN, since
2296                                                  * the command is treated as untagged further on.
2297                                                  */
2298                                                 cmd->device->tagged_supported = 0;
2299                                                 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2300                                                 cmd->tag = TAG_NONE;
2301                                                 TAG_PRINTK("scsi%d: target %d lun %d rejected "
2302                                                            "QUEUE_TAG message; tagged queuing "
2303                                                            "disabled\n",
2304                                                            HOSTNO, cmd->device->id, cmd->device->lun);
2305                                                 break;
2306                                         }
2307                                         break;
2308                                 case DISCONNECT:
2309                                         /* Accept message by clearing ACK */
2310                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2311                                         local_irq_save(flags);
2312                                         cmd->device->disconnect = 1;
2313                                         LIST(cmd,hostdata->disconnected_queue);
2314                                         SET_NEXT(cmd, hostdata->disconnected_queue);
2315                                         hostdata->connected = NULL;
2316                                         hostdata->disconnected_queue = cmd;
2317                                         local_irq_restore(flags);
2318                                         QU_PRINTK("scsi%d: command for target %d lun %d was "
2319                                                   "moved from connected to the "
2320                                                   "disconnected_queue\n", HOSTNO,
2321                                                   cmd->device->id, cmd->device->lun);
2322                                         /*
2323                                          * Restore phase bits to 0 so an interrupted selection,
2324                                          * arbitration can resume.
2325                                          */
2326                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2327
2328                                         /* Enable reselect interrupts */
2329                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2330                                         /* Wait for bus free to avoid nasty timeouts */
2331                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2332                                                 barrier();
2333                                         return;
2334                                         /*
2335                                          * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2336                                          * operation, in violation of the SCSI spec so we can safely
2337                                          * ignore SAVE/RESTORE pointers calls.
2338                                          *
2339                                          * Unfortunately, some disks violate the SCSI spec and
2340                                          * don't issue the required SAVE_POINTERS message before
2341                                          * disconnecting, and we have to break spec to remain
2342                                          * compatible.
2343                                          */
2344                                 case SAVE_POINTERS:
2345                                 case RESTORE_POINTERS:
2346                                         /* Accept message by clearing ACK */
2347                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2348                                         /* Enable reselect interrupts */
2349                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2350                                         break;
2351                                 case EXTENDED_MESSAGE:
2352                                         /*
2353                                          * Extended messages are sent in the following format :
2354                                          * Byte
2355                                          * 0            EXTENDED_MESSAGE == 1
2356                                          * 1            length (includes one byte for code, doesn't
2357                                          *              include first two bytes)
2358                                          * 2            code
2359                                          * 3..length+1  arguments
2360                                          *
2361                                          * Start the extended message buffer with the EXTENDED_MESSAGE
2362                                          * byte, since spi_print_msg() wants the whole thing.
2363                                          */
2364                                         extended_msg[0] = EXTENDED_MESSAGE;
2365                                         /* Accept first byte by clearing ACK */
2366                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2367
2368                                         EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO);
2369
2370                                         len = 2;
2371                                         data = extended_msg + 1;
2372                                         phase = PHASE_MSGIN;
2373                                         NCR5380_transfer_pio(instance, &phase, &len, &data);
2374                                         EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2375                                                    (int)extended_msg[1], (int)extended_msg[2]);
2376
2377                                         if (!len && extended_msg[1] <=
2378                                             (sizeof(extended_msg) - 1)) {
2379                                                 /* Accept third byte by clearing ACK */
2380                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2381                                                 len = extended_msg[1] - 1;
2382                                                 data = extended_msg + 3;
2383                                                 phase = PHASE_MSGIN;
2384
2385                                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2386                                                 EXT_PRINTK("scsi%d: message received, residual %d\n",
2387                                                            HOSTNO, len);
2388
2389                                                 switch (extended_msg[2]) {
2390                                                 case EXTENDED_SDTR:
2391                                                 case EXTENDED_WDTR:
2392                                                 case EXTENDED_MODIFY_DATA_POINTER:
2393                                                 case EXTENDED_EXTENDED_IDENTIFY:
2394                                                         tmp = 0;
2395                                                 }
2396                                         } else if (len) {
2397                                                 printk(KERN_NOTICE "scsi%d: error receiving "
2398                                                        "extended message\n", HOSTNO);
2399                                                 tmp = 0;
2400                                         } else {
2401                                                 printk(KERN_NOTICE "scsi%d: extended message "
2402                                                            "code %02x length %d is too long\n",
2403                                                            HOSTNO, extended_msg[2], extended_msg[1]);
2404                                                 tmp = 0;
2405                                         }
2406                                         /* Fall through to reject message */
2407
2408                                         /*
2409                                          * If we get something weird that we aren't expecting,
2410                                          * reject it.
2411                                          */
2412                                 default:
2413                                         if (!tmp) {
2414                                                 printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO);
2415                                                 spi_print_msg(extended_msg);
2416                                                 printk("\n");
2417                                         } else if (tmp != EXTENDED_MESSAGE)
2418                                                 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2419                                                        "message %02x from target %d, lun %d\n",
2420                                                        HOSTNO, tmp, cmd->device->id, cmd->device->lun);
2421                                         else
2422                                                 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2423                                                        "extended message "
2424                                                        "code %02x, length %d from target %d, lun %d\n",
2425                                                        HOSTNO, extended_msg[1], extended_msg[0],
2426                                                        cmd->device->id, cmd->device->lun);
2427
2428
2429                                         msgout = MESSAGE_REJECT;
2430                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2431                                         break;
2432                                 } /* switch (tmp) */
2433                                 break;
2434                         case PHASE_MSGOUT:
2435                                 len = 1;
2436                                 data = &msgout;
2437                                 hostdata->last_message = msgout;
2438                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2439                                 if (msgout == ABORT) {
2440 #ifdef SUPPORT_TAGS
2441                                         cmd_free_tag(cmd);
2442 #else
2443                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2444 #endif
2445                                         hostdata->connected = NULL;
2446                                         cmd->result = DID_ERROR << 16;
2447 #ifdef NCR5380_STATS
2448                                         collect_stats(hostdata, cmd);
2449 #endif
2450                                         cmd->scsi_done(cmd);
2451                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2452                                         falcon_release_lock_if_possible(hostdata);
2453                                         return;
2454                                 }
2455                                 msgout = NOP;
2456                                 break;
2457                         case PHASE_CMDOUT:
2458                                 len = cmd->cmd_len;
2459                                 data = cmd->cmnd;
2460                                 /*
2461                                  * XXX for performance reasons, on machines with a
2462                                  * PSEUDO-DMA architecture we should probably
2463                                  * use the dma transfer function.
2464                                  */
2465                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2466                                 break;
2467                         case PHASE_STATIN:
2468                                 len = 1;
2469                                 data = &tmp;
2470                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2471                                 cmd->SCp.Status = tmp;
2472                                 break;
2473                         default:
2474                                 printk("scsi%d: unknown phase\n", HOSTNO);
2475                                 NCR_PRINT(NDEBUG_ANY);
2476                         } /* switch(phase) */
2477                 } /* if (tmp * SR_REQ) */
2478         } /* while (1) */
2479 }
2480
2481 /*
2482  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2483  *
2484  * Purpose : does reselection, initializing the instance->connected
2485  *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2486  *      nexus has been reestablished,
2487  *
2488  * Inputs : instance - this instance of the NCR5380.
2489  *
2490  */
2491
2492
2493 static void NCR5380_reselect(struct Scsi_Host *instance)
2494 {
2495         SETUP_HOSTDATA(instance);
2496         unsigned char target_mask;
2497         unsigned char lun, phase;
2498         int len;
2499 #ifdef SUPPORT_TAGS
2500         unsigned char tag;
2501 #endif
2502         unsigned char msg[3];
2503         unsigned char *data;
2504         Scsi_Cmnd *tmp = NULL, *prev;
2505 /*      unsigned long flags; */
2506
2507         /*
2508          * Disable arbitration, etc. since the host adapter obviously
2509          * lost, and tell an interrupted NCR5380_select() to restart.
2510          */
2511
2512         NCR5380_write(MODE_REG, MR_BASE);
2513         hostdata->restart_select = 1;
2514
2515         target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2516
2517         RSL_PRINTK("scsi%d: reselect\n", HOSTNO);
2518
2519         /*
2520          * At this point, we have detected that our SCSI ID is on the bus,
2521          * SEL is true and BSY was false for at least one bus settle delay
2522          * (400 ns).
2523          *
2524          * We must assert BSY ourselves, until the target drops the SEL
2525          * signal.
2526          */
2527
2528         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2529
2530         while (NCR5380_read(STATUS_REG) & SR_SEL)
2531                 ;
2532         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2533
2534         /*
2535          * Wait for target to go into MSGIN.
2536          */
2537
2538         while (!(NCR5380_read(STATUS_REG) & SR_REQ))
2539                 ;
2540
2541         len = 1;
2542         data = msg;
2543         phase = PHASE_MSGIN;
2544         NCR5380_transfer_pio(instance, &phase, &len, &data);
2545
2546         if (!(msg[0] & 0x80)) {
2547                 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
2548                 spi_print_msg(msg);
2549                 do_abort(instance);
2550                 return;
2551         }
2552         lun = (msg[0] & 0x07);
2553
2554 #ifdef SUPPORT_TAGS
2555         /* If the phase is still MSGIN, the target wants to send some more
2556          * messages. In case it supports tagged queuing, this is probably a
2557          * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2558          */
2559         tag = TAG_NONE;
2560         if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
2561                 /* Accept previous IDENTIFY message by clearing ACK */
2562                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2563                 len = 2;
2564                 data = msg + 1;
2565                 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2566                     msg[1] == SIMPLE_QUEUE_TAG)
2567                         tag = msg[2];
2568                 TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at "
2569                            "reselection\n", HOSTNO, target_mask, lun, tag);
2570         }
2571 #endif
2572
2573         /*
2574          * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we
2575          * just reestablished, and remove it from the disconnected queue.
2576          */
2577
2578         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL;
2579              tmp; prev = tmp, tmp = NEXT(tmp)) {
2580                 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2581 #ifdef SUPPORT_TAGS
2582                     && (tag == tmp->tag)
2583 #endif
2584                     ) {
2585                         /* ++guenther: prevent race with falcon_release_lock */
2586                         falcon_dont_release++;
2587                         if (prev) {
2588                                 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2589                                 SET_NEXT(prev, NEXT(tmp));
2590                         } else {
2591                                 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
2592                                 hostdata->disconnected_queue = NEXT(tmp);
2593                         }
2594                         SET_NEXT(tmp, NULL);
2595                         break;
2596                 }
2597         }
2598
2599         if (!tmp) {
2600                 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
2601 #ifdef SUPPORT_TAGS
2602                        "tag %d "
2603 #endif
2604                        "not in disconnected_queue.\n",
2605                        HOSTNO, target_mask, lun
2606 #ifdef SUPPORT_TAGS
2607                        , tag
2608 #endif
2609                         );
2610                 /*
2611                  * Since we have an established nexus that we can't do anything
2612                  * with, we must abort it.
2613                  */
2614                 do_abort(instance);
2615                 return;
2616         }
2617
2618         /* Accept message by clearing ACK */
2619         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2620
2621         hostdata->connected = tmp;
2622         RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n",
2623                    HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
2624         falcon_dont_release--;
2625 }
2626
2627
2628 /*
2629  * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2630  *
2631  * Purpose : abort a command
2632  *
2633  * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2634  *      host byte of the result field to, if zero DID_ABORTED is
2635  *      used.
2636  *
2637  * Returns : 0 - success, -1 on failure.
2638  *
2639  * XXX - there is no way to abort the command that is currently
2640  *       connected, you have to wait for it to complete.  If this is
2641  *       a problem, we could implement longjmp() / setjmp(), setjmp()
2642  *       called where the loop started in NCR5380_main().
2643  */
2644
2645 static
2646 int NCR5380_abort(Scsi_Cmnd *cmd)
2647 {
2648         struct Scsi_Host *instance = cmd->device->host;
2649         SETUP_HOSTDATA(instance);
2650         Scsi_Cmnd *tmp, **prev;
2651         unsigned long flags;
2652
2653         printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO);
2654         scsi_print_command(cmd);
2655
2656         NCR5380_print_status(instance);
2657
2658         local_irq_save(flags);
2659
2660         if (!IS_A_TT() && !falcon_got_lock)
2661                 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n",
2662                        HOSTNO);
2663
2664         ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2665                     NCR5380_read(BUS_AND_STATUS_REG),
2666                     NCR5380_read(STATUS_REG));
2667
2668 #if 1
2669         /*
2670          * Case 1 : If the command is the currently executing command,
2671          * we'll set the aborted flag and return control so that
2672          * information transfer routine can exit cleanly.
2673          */
2674
2675         if (hostdata->connected == cmd) {
2676
2677                 ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO);
2678                 /*
2679                  * We should perform BSY checking, and make sure we haven't slipped
2680                  * into BUS FREE.
2681                  */
2682
2683                 /*      NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2684                 /*
2685                  * Since we can't change phases until we've completed the current
2686                  * handshake, we have to source or sink a byte of data if the current
2687                  * phase is not MSGOUT.
2688                  */
2689
2690                 /*
2691                  * Return control to the executing NCR drive so we can clear the
2692                  * aborted flag and get back into our main loop.
2693                  */
2694
2695                 if (do_abort(instance) == 0) {
2696                         hostdata->aborted = 1;
2697                         hostdata->connected = NULL;
2698                         cmd->result = DID_ABORT << 16;
2699 #ifdef SUPPORT_TAGS
2700                         cmd_free_tag(cmd);
2701 #else
2702                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2703 #endif
2704                         local_irq_restore(flags);
2705                         cmd->scsi_done(cmd);
2706                         falcon_release_lock_if_possible(hostdata);
2707                         return SCSI_ABORT_SUCCESS;
2708                 } else {
2709 /*                      local_irq_restore(flags); */
2710                         printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2711                         return SCSI_ABORT_ERROR;
2712                 }
2713         }
2714 #endif
2715
2716         /*
2717          * Case 2 : If the command hasn't been issued yet, we simply remove it
2718          *          from the issue queue.
2719          */
2720         for (prev = (Scsi_Cmnd **)&(hostdata->issue_queue),
2721              tmp = (Scsi_Cmnd *)hostdata->issue_queue;
2722              tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
2723                 if (cmd == tmp) {
2724                         REMOVE(5, *prev, tmp, NEXT(tmp));
2725                         (*prev) = NEXT(tmp);
2726                         SET_NEXT(tmp, NULL);
2727                         tmp->result = DID_ABORT << 16;
2728                         local_irq_restore(flags);
2729                         ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n",
2730                                     HOSTNO);
2731                         /* Tagged queuing note: no tag to free here, hasn't been assigned
2732                          * yet... */
2733                         tmp->scsi_done(tmp);
2734                         falcon_release_lock_if_possible(hostdata);
2735                         return SCSI_ABORT_SUCCESS;
2736                 }
2737         }
2738
2739         /*
2740          * Case 3 : If any commands are connected, we're going to fail the abort
2741          *          and let the high level SCSI driver retry at a later time or
2742          *          issue a reset.
2743          *
2744          *          Timeouts, and therefore aborted commands, will be highly unlikely
2745          *          and handling them cleanly in this situation would make the common
2746          *          case of noresets less efficient, and would pollute our code.  So,
2747          *          we fail.
2748          */
2749
2750         if (hostdata->connected) {
2751                 local_irq_restore(flags);
2752                 ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO);
2753                 return SCSI_ABORT_SNOOZE;
2754         }
2755
2756         /*
2757          * Case 4: If the command is currently disconnected from the bus, and
2758          *      there are no connected commands, we reconnect the I_T_L or
2759          *      I_T_L_Q nexus associated with it, go into message out, and send
2760          *      an abort message.
2761          *
2762          * This case is especially ugly. In order to reestablish the nexus, we
2763          * need to call NCR5380_select().  The easiest way to implement this
2764          * function was to abort if the bus was busy, and let the interrupt
2765          * handler triggered on the SEL for reselect take care of lost arbitrations
2766          * where necessary, meaning interrupts need to be enabled.
2767          *
2768          * When interrupts are enabled, the queues may change - so we
2769          * can't remove it from the disconnected queue before selecting it
2770          * because that could cause a failure in hashing the nexus if that
2771          * device reselected.
2772          *
2773          * Since the queues may change, we can't use the pointers from when we
2774          * first locate it.
2775          *
2776          * So, we must first locate the command, and if NCR5380_select()
2777          * succeeds, then issue the abort, relocate the command and remove
2778          * it from the disconnected queue.
2779          */
2780
2781         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp;
2782              tmp = NEXT(tmp)) {
2783                 if (cmd == tmp) {
2784                         local_irq_restore(flags);
2785                         ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO);
2786
2787                         if (NCR5380_select(instance, cmd, (int)cmd->tag))
2788                                 return SCSI_ABORT_BUSY;
2789
2790                         ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO);
2791
2792                         do_abort(instance);
2793
2794                         local_irq_save(flags);
2795                         for (prev = (Scsi_Cmnd **)&(hostdata->disconnected_queue),
2796                              tmp = (Scsi_Cmnd *)hostdata->disconnected_queue;
2797                              tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
2798                                 if (cmd == tmp) {
2799                                         REMOVE(5, *prev, tmp, NEXT(tmp));
2800                                         *prev = NEXT(tmp);
2801                                         SET_NEXT(tmp, NULL);
2802                                         tmp->result = DID_ABORT << 16;
2803                                         /* We must unlock the tag/LUN immediately here, since the
2804                                          * target goes to BUS FREE and doesn't send us another
2805                                          * message (COMMAND_COMPLETE or the like)
2806                                          */
2807 #ifdef SUPPORT_TAGS
2808                                         cmd_free_tag(tmp);
2809 #else
2810                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2811 #endif
2812                                         local_irq_restore(flags);
2813                                         tmp->scsi_done(tmp);
2814                                         falcon_release_lock_if_possible(hostdata);
2815                                         return SCSI_ABORT_SUCCESS;
2816                                 }
2817                         }
2818                 }
2819         }
2820
2821         /*
2822          * Case 5 : If we reached this point, the command was not found in any of
2823          *          the queues.
2824          *
2825          * We probably reached this point because of an unlikely race condition
2826          * between the command completing successfully and the abortion code,
2827          * so we won't panic, but we will notify the user in case something really
2828          * broke.
2829          */
2830
2831         local_irq_restore(flags);
2832         printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully\n"
2833                KERN_INFO "        before abortion\n", HOSTNO);
2834
2835         /* Maybe it is sufficient just to release the ST-DMA lock... (if
2836          * possible at all) At least, we should check if the lock could be
2837          * released after the abort, in case it is kept due to some bug.
2838          */
2839         falcon_release_lock_if_possible(hostdata);
2840
2841         return SCSI_ABORT_NOT_RUNNING;
2842 }
2843
2844
2845 /*
2846  * Function : int NCR5380_reset (Scsi_Cmnd *cmd)
2847  *
2848  * Purpose : reset the SCSI bus.
2849  *
2850  * Returns : SCSI_RESET_WAKEUP
2851  *
2852  */
2853
2854 static int NCR5380_bus_reset(Scsi_Cmnd *cmd)
2855 {
2856         SETUP_HOSTDATA(cmd->device->host);
2857         int i;
2858         unsigned long flags;
2859 #if 1
2860         Scsi_Cmnd *connected, *disconnected_queue;
2861 #endif
2862
2863         if (!IS_A_TT() && !falcon_got_lock)
2864                 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n",
2865                        H_NO(cmd));
2866
2867         NCR5380_print_status(cmd->device->host);
2868
2869         /* get in phase */
2870         NCR5380_write(TARGET_COMMAND_REG,
2871                       PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG)));
2872         /* assert RST */
2873         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
2874         udelay(40);
2875         /* reset NCR registers */
2876         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2877         NCR5380_write(MODE_REG, MR_BASE);
2878         NCR5380_write(TARGET_COMMAND_REG, 0);
2879         NCR5380_write(SELECT_ENABLE_REG, 0);
2880         /* ++roman: reset interrupt condition! otherwise no interrupts don't get
2881          * through anymore ... */
2882         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2883
2884 #if 1   /* XXX Should now be done by midlevel code, but it's broken XXX */
2885         /* XXX see below                                            XXX */
2886
2887         /* MSch: old-style reset: actually abort all command processing here */
2888
2889         /* After the reset, there are no more connected or disconnected commands
2890          * and no busy units; to avoid problems with re-inserting the commands
2891          * into the issue_queue (via scsi_done()), the aborted commands are
2892          * remembered in local variables first.
2893          */
2894         local_irq_save(flags);
2895         connected = (Scsi_Cmnd *)hostdata->connected;
2896         hostdata->connected = NULL;
2897         disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue;
2898         hostdata->disconnected_queue = NULL;
2899 #ifdef SUPPORT_TAGS
2900         free_all_tags();
2901 #endif
2902         for (i = 0; i < 8; ++i)
2903                 hostdata->busy[i] = 0;
2904 #ifdef REAL_DMA
2905         hostdata->dma_len = 0;
2906 #endif
2907         local_irq_restore(flags);
2908
2909         /* In order to tell the mid-level code which commands were aborted,
2910          * set the command status to DID_RESET and call scsi_done() !!!
2911          * This ultimately aborts processing of these commands in the mid-level.
2912          */
2913
2914         if ((cmd = connected)) {
2915                 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2916                 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2917                 cmd->scsi_done(cmd);
2918         }
2919
2920         for (i = 0; (cmd = disconnected_queue); ++i) {
2921                 disconnected_queue = NEXT(cmd);
2922                 SET_NEXT(cmd, NULL);
2923                 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2924                 cmd->scsi_done(cmd);
2925         }
2926         if (i > 0)
2927                 ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i);
2928
2929         /* The Falcon lock should be released after a reset...
2930          */
2931         /* ++guenther: moved to atari_scsi_reset(), to prevent a race between
2932          * unlocking and enabling dma interrupt.
2933          */
2934 /*      falcon_release_lock_if_possible( hostdata );*/
2935
2936         /* since all commands have been explicitly terminated, we need to tell
2937          * the midlevel code that the reset was SUCCESSFUL, and there is no
2938          * need to 'wake up' the commands by a request_sense
2939          */
2940         return SCSI_RESET_SUCCESS | SCSI_RESET_BUS_RESET;
2941 #else /* 1 */
2942
2943         /* MSch: new-style reset handling: let the mid-level do what it can */
2944
2945         /* ++guenther: MID-LEVEL IS STILL BROKEN.
2946          * Mid-level is supposed to requeue all commands that were active on the
2947          * various low-level queues. In fact it does this, but that's not enough
2948          * because all these commands are subject to timeout. And if a timeout
2949          * happens for any removed command, *_abort() is called but all queues
2950          * are now empty. Abort then gives up the falcon lock, which is fatal,
2951          * since the mid-level will queue more commands and must have the lock
2952          * (it's all happening inside timer interrupt handler!!).
2953          * Even worse, abort will return NOT_RUNNING for all those commands not
2954          * on any queue, so they won't be retried ...
2955          *
2956          * Conclusion: either scsi.c disables timeout for all resetted commands
2957          * immediately, or we lose!  As of linux-2.0.20 it doesn't.
2958          */
2959
2960         /* After the reset, there are no more connected or disconnected commands
2961          * and no busy units; so clear the low-level status here to avoid
2962          * conflicts when the mid-level code tries to wake up the affected
2963          * commands!
2964          */
2965
2966         if (hostdata->issue_queue)
2967                 ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2968         if (hostdata->connected)
2969                 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2970         if (hostdata->disconnected_queue)
2971                 ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
2972
2973         local_irq_save(flags);
2974         hostdata->issue_queue = NULL;
2975         hostdata->connected = NULL;
2976         hostdata->disconnected_queue = NULL;
2977 #ifdef SUPPORT_TAGS
2978         free_all_tags();
2979 #endif
2980         for (i = 0; i < 8; ++i)
2981                 hostdata->busy[i] = 0;
2982 #ifdef REAL_DMA
2983         hostdata->dma_len = 0;
2984 #endif
2985         local_irq_restore(flags);
2986
2987         /* we did no complete reset of all commands, so a wakeup is required */
2988         return SCSI_RESET_WAKEUP | SCSI_RESET_BUS_RESET;
2989 #endif /* 1 */
2990 }